Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/14/14
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
406 AM PDT Sat Apr 12 2014
.Synopsis...
A weak system will bring a slight chance of showers and
thunderstorms over the southern Sierra this afternoon. High
pressure and well above normal temperatures dominate into early
next week, followed by a series of weak troughs that move through
northern California by the middle of next week.
&&
.Short Term Discussion (Today through Monday)...
A weak disturbance passing through Socal will bring a slight
chance of thunderstorms over Tuolumne and Alpine counties mainly
near the crest late this afternoon. HRRR actually keeps all of the
activity south and east of these areas with increasing northwest
mid-level flow. However...with instability nearby shown in
modified totals/totals will keep slight chances going.
Temperatures will be cooler Today with increased onshore flow and
lowered heights and did lower highs a few degrees. Valley highs
will be low 80`s north Redding-Red Bluff...low to upper 70`s south
Sacramento to Modesto and mid to upper 60`s delta. Wind gusts up
to 30 mph will be possible through the delta through the day.
Disturbance will move east into the great basin area Sunday with
ridge building east from the Pacific. Northern flow will briefly
develop in this pattern and north wind gusts up to 25 mph will be
possible over the western Sacramento valley from late morning
through the day. Otherwise dry and warm with temperatures warming
back into the low 80`s over most of the area.
Upper ridge builds over Norcal Monday and Tuesday with weak
disturbances brushing Shasta county. Expect only increased cloud
cover given the limited moisture and have went with a dry forecast
for these days. Temperatures will remain in the low 80`s.
&&
.Extended Discussion (Wednesday through Saturday)
Dry northwesterly flow aloft sets up over NorCal Wed/Thur on the
backside of an upper-low digging over the Rocky Mountain states.
The GFS is much more vigorous with the low than the EC, but
either way it will much to far to our east to do much other than
cool temps a bit and bring some dry north winds if the GFS
solution is correct. Model disparity is readily apparent in the
high temperature forecast for Wednesday in the Sac area, where
the raw GFS is > 10F cooler than the raw EC. Current forecast
splits the difference with model consensus.
A Pacific trough is progged to approach the far Northern CA
coastline by the weekend, though model confidence metrics show
little predictability in this feature. Have thus kept near climo
pops for now for areas north of I-80 (which translates to a
chance of showers for the mountains with little to no chance in
the Valley). -DVC
&&
.Aviation...
VFR next 24 hours for Interior NorCal TAF sites as an upper low
drifts by to the south with little impact on area weather. Few
isolated showers/thunderstorms over the mountains this afternoon.
Generally light winds around 10 knots or less, except SW 15-25
knots in the Delta area, and up to 15 kts for airports in the
near vicinity including KSMF and KSAC. -DVC
&&
.STO Watches/Warnings/Advisories...
None.
&&
$$
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
812 PM MDT SUN APR 13 2014
.UPDATE...
&&
.SHORT TERM...SNOW WAS GRADUALLY DECREASING FROM NORTH TO SOUTH
ACROSS THE AREA AS THE MAIN UPPER LEVEL SYSTEM WAS MOVING INTO
SOUTHERN COLORADO. HAVE CANCELLED SOME OF THE HIGHLIGHTS OVER NRN
AREAS AND THE REST SHOULD EXPIRE AT MIDNIGHT BASED ON CURRENT
TRENDS.
.AVIATION...MAIN SNOW AREA HAD MOVED SOUTH OF DIA HOWEVER WILL
STILL SEE SOME LINGERING LIGHT SNOW THROUGH MIDNIGHT. ANY
ADDITIONAL ACCUMULATION WILL BE UNDER ONE HALF INCH.
&&
.PREV DISCUSSION... /ISSUED 327 PM MDT SUN APR 13 2014/
SHORT TERM...MAIN UPPER TROUGH IS PRESENTLY MOVING OVER THE
COLORADO WESTERN SLOPE AND CENTRAL MOUNTAINS. INTENSE SNOW SHOWER
ACTIVITY HAS DEVELOPED OVER THE MOUNTAINS WITH SNOWFALL RATES OF
ONE TO TWO INCHES PER HOUR IN SUMMIT COUNTY FOR THE LAST COUPLE
HOURS. LIGHTNING NETWORKS HAVE SHOWN SOME THUNDERSTORMS OVER
GUNNISON AND THE SAN JUAN MOUNTAINS. HAVE ADDED THE MENTION OF
ISOLATED THUNDER TO THE MOUNTAIN ZONES FOR THE EARLY PARTS OF THIS
EVENING. WITH THE MODERATE AND HEAVY SNOW OCCURRING IN THE
MOUNTAINS AT THE PRESENT TIME...WILL CONTINUE ALL OF THE WARNINGS
AND ADVISORIES. DEPENDING ON THE PROGRESS OF THE UPPER TROUGH
THROUGH THE EVENING HOURS...HIGHLIGHTS MAY BE ABLE TO BE CANCELLED
BY MID-EVENING.
CONCERNING SNOWFALL AMOUNTS ON THE PLAINS...MESOSCALE AND HI-RES
MODELS HAVE TRENDED AWAY FROM AN AREA OF HEAVY SNOW OVER THE
NORTHEAST CORNER OF THE STATE. HOWEVER...THE RAP DOES SHOW 3-4+
INCHES OF SNOW ACROSS MOST OF THE PLAINS. WILL NOT ISSUE ANY NEW
ADVISORIES...BUT WILL BE MENTIONING 2 TO 5 INCHES OF NEW SNOW IN
THE FIRST FORECAST PERIOD. GUSTY NORTH WINDS UP TO 35 MPH SHOULD
CONTINUE WELL INTO THE EVENING...SO WILL BE MENTIONING AREAS OF
BLOWING SNOW.
LATER TONIGHT...THE MODELS ALL POINT TO STRONG SUBSIDENCE BEHIND
THIS TROUGH AND RAPID IMPROVEMENT OF WEATHER AFTER MIDNIGHT.
TOMORROW WILL CONTINUE DRY WITH SOME WARMING WHICH WILL BE LIMITED
BY THE AMOUNTS OF SOIL MOISTURE LEFT OVER FROM TODAY AND TONIGHT
SNOW EVENT.
LONG TERM...HIGH PRESSURE RIDGING ALOFT WILL BUILD OVER THE
REGION ON MONDAY NIGHT AND TUESDAY. THIS WILL RESULT IN DRYING AND
A WARMING TREND WITH READINGS BACK TO NEAR 60 DEGREES OVER LOWER
ELEVATIONS ON TUESDAY.
THE NEXT UPPER LEVEL DISTURBANCE WILL MOVE INTO COLORADO ON
WEDNESDAY THROUGH EARLY THURSDAY WITH THE NEXT CHANCE OF RAIN AND
SNOW. THE LONG RANGE MODELS ARE IN A BIT BETTER AGREEMENT TODAY
BUT GFS STILL SHOWING THE STRONGEST AND DEEPEST SOLUTION. WITH A
BIT BETTER CONTINUITY WILL TREND LOWER TEMPERATURES AND A BIT
HIGHER CHANCES OF PRECIP FOR THIS PERIOD. DRY AND WARMER AGAIN FOR
LATER IN THE WEEK.
AVIATION...IFR CONDITIONS WILL PERSIST THROUGH THE EVENING AS THE
UPPER DISTURBANCE MOVES FROM THE MOUNTAINS OUT OVER THE PLAINS.
EMBEDDED SHOWER ACTIVITY WITHIN THE PRECIPITATION FIELD WILL BE
CAPABLE OF PRODUCING MODERATE TO HEAVY SNOW AT TIMES. SNOWFALL
RATES MAY EXCEED ONE INCH PER HOUR...BUT WILL GENERATLLY BE LESS
THAN ONE-HALF INCH PER HOUR. AS TEMPERATURES COOL IN THE
EVENING...ACCUMULATION OF SNOW WILL INCREASE. NORTH WINDS GUSTING
TO NEAR 25 KNOTS WILL GENERALLY NOT BE STRONG ENOUGH TO GENERATE
ANY BLOWING SNOW. CONDITIONS SHOULD BE IMPROVING BEGIN APPROVING
BY ABOUT 03Z WITH SNOW ENDING AROUND 06Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR COZ037-
040-045>047.
WINTER STORM WARNING UNTIL MIDNIGHT MDT TONIGHT FOR COZ033-034-
036-041.
&&
$$
SHORT TERM...RPK
LONG TERM....ENTREKIN
AVIATION...BAKER
AREA FORECAST DISCUSSION
NWS BOISE ID
957 AM MDT SAT APR 12 2014
.DISCUSSION...LATEST HRRR DEVELOPS ISOLATED SHOWERS NEAR VALLEY
COUNTY TOWARDS 6 PM. 12Z NAM DOES DEVELOP LOW/MID CLOUD IN MAGIC
VALLEY CONVERGENCE ZONE AROUND 9Z AND TAKES IT AS FAR WEST AS THE
GOODING/ELMORE COUNTY LINES. PLAN TO INCREASE POPS AND TREND A
LITTLE FARTHER WEST FOR THIS 6-12Z TONIGHT. GUSTY WINDS AND COOLER
TEMPERATURES THIS AFTERNOON STILL ON TRACK FOLLOWING THE FRONT.
&&
.AVIATION...WIDESPREAD VFR UNDER SCT-BKN HIGH CLOUDS. SCATTERED
CUMULUS DECK /BASE 10K FT MSL/ TO DEVELOP AROUND 20Z. LIGHT TO
MODERATE SURFACE WINDS WILL STRENGTHEN THIS AFTERNOON. EXPECT W/NW
SFC WINDS 10 TO 20 KTS WITH GUSTS 25 TO 35 KTS BETWEEN 18Z AND 03Z.
NORTHWESTERLY WINDS ALOFT WILL AVERAGE 25 KTS THROUGH 10K FT MSL.
&&
.PREV DISCUSSION...
SHORT TERM...TODAY THROUGH SUNDAY...A DRY COLD FRONTAL PASSAGE
EARLY THIS MORNING WILL BE FOLLOWED BY AN UPPER LEVEL TROUGH AND
SURFACE HIGH LATER TODAY AND TONIGHT. ISOLATED SHOWERS DEVELOP
OVER THE CENTRAL IDAHO MTNS THIS AFTERNOON IN RESPONSE TO THE
UPPER LEVEL ENERGY AND AFTERNOON INSTABILITY. ALSO OF NOTE WILL BE
THE DEVELOPMENT OF GUSTY NORTH TO NORTHWEST WINDS LATER TODAY AS
THE SURFACE PRESSURE GRADIENT STRENGTHENS. GUSTS AROUND 40 MPH
WILL DEVELOP EAST OF MOUNTAIN HOME WITH SLIGHTLY LESSER SPEEDS TO
THE WEST. THE WINDS WILL DIMINISH SOME THIS EVENING BUT EXPECT
BREEZY CONDITIONS TO CONTINUE ACROSS OPEN VALLEYS THROUGH TONIGHT.
PRECIPITATION DEVELOPMENT FROM LATE THIS AFTERNOON THROUGH SUNDAY
AFTERNOON WILL REMAIN FOCUSED NEAR THE BASE OF THE TROUGH WHICH
SPLITS IDAHO AS IT TRACKS FROM NORTH TO SOUTH. MODELS ARE ALSO
SHOWING AN AREA OF SURFACE CONVERGENCE IN THE MAGIC VALLEY THAT
COULD BRING A PERIOD OF LIGHT RAIN FROM LATE TONIGHT INTO SUNDAY.
DRY AIR MOVES IN BEHIND THE SYSTEM SO BY SUNDAY AFTERNOON ONLY
THE WESTERN MAGIC VALLEY WILL BE HOLDING ONTO CLOUDS AND A SLIGHT
CHANCE OF RAIN. A FEW DEGREES COOLER ON SUNDAY UNDER THE NORTHERLY
FLOW THOUGH STILL HOLDING NEAR NORMAL.
LONG TERM...SUNDAY NIGHT THROUGH FRIDAY...SUNDAY NIGHT THROUGH
TUESDAY MODELS IN FAIRLY GOOD AGREEMENT BUT DIVERGE QUICKLY
TUESDAY NIGHT AND ARE OUT OF PHASE BY FRIDAY. NOT A LOT OF RUN TO
RUN CONSISTENCY WITH THE MODELS WITH THE ECMWF HAVING THE SMALLEST
CHANGES WHILE THE GFS HAS BIG CHANGES. LOW FORECASTER CONFIDENCE
IN THE MODELS IN THE EXTENDED BUT SINCE THE ECMWF DOES NOT CHANGE
AS MUCH AS THE GFS FROM RUN TO RUN WILL TREND THE FORECAST TOWARDS
THE ECMWF. WITH THE LATEST TREND EXPECT DRY CONDITIONS OVER THE
FORECAST AREA SUNDAY NIGHT THROUGH MONDAY NIGHT AS THE AXIS OF A
RIDGE OF HIGH PRESSURE MOVES EAST OVER THE REGION. TUESDAY A
WEAKENING UPPER LEVEL TROUGH THAT IS DAMPENING THE RIDGE WILL MOVE
SOUTHEAST OVER THE FORECAST AREA THROUGH WEDNESDAY FOR CHANCE POPS
OVER HIGHER TERRAIN AND MOSTLY DRY CONDITIONS OVER THE LOWEST
VALLEYS. WEDNESDAY NIGHT THROUGH FRIDAY A FLAT RIDGE DEVELOPS OVER
THE PACIFIC NORTHWEST BUT ENOUGH MOISTURE MOVING THROUGH THE FLOW
FOR CHANCE POPS OVER HIGHER TERRAIN AND SLIGHT CHANCE OVER LOWER
VALLEYS. TEMPERATURES THROUGH THE EXTENDED WILL AVERAGE A FEW
DEGREES ABOVE NORMAL WITH THE COOLEST DAY ON WEDNESDAY WITH HIGH
TEMPERATURES A FEW DEGREES BELOW NORMAL.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.
&&
$$
WEATHER.GOV/BOISE
DISCUSSION...VM
AVIATION.....MT
PREV SHORT TERM...DG
PREV LONG TERM....JA
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1105 AM CDT SAT APR 12 2014
.DISCUSSION...
306 AM CDT
TODAY...
THIS MORNING...LOW PRESSURE IS CENTERED OVER SOUTH DAKOTA WHILE A
WARM FRONT STRETCHES EAST ACROSS CENTRAL IOWA TO NEAR ROCHELLE AND
EAST INTO CHICAGO. THE WARM FRONT WILL LIFT NORTH INTO WISCONSIN
BY LATE THIS MORNING. WEAK CONVECTION HAS DEVELOPED ACROSS
NORTHWESTERN IOWA EARLY THIS MORNING AND IS PROGGED TO MOVE ALONG
THE IL/WI STATE LINE THIS MORNING...THOUGH SHOULD DISSIPATE AS IT
OUTRUNS THE MEAGER INSTABILITY CURRENTLY IN PLACE TO OUR WEST. AS
THE WARM FRONT LIFTS NORTH OF THE AREA TODAY...MID 50 DEWPOINTS IN
PLACE ACROSS FAR DOWNSTATE ILLINOIS WILL ALSO OVERSPREAD THE
AREA...ACCOMPANIED BY TEMPERATURES EXPECTED TO PUSH INTO MID TO
UPPER 70S RESULTING IN MODERATE SURFACE BASED INSTABILITY DEVELOPING
THIS AFTERNOON. MLCAPE VALUES IN EXCESS OF 1000 J/KG ARE EXPECTED
ESPECIALLY IN THE WESTERN COUNTIES THIS AFTERNOON...THOUGH SHOULD
REMAIN CAPPED AS THE BEST FORCING WILL BE TO OUR NORTH. THE CAPPING
DOES ERODE AS YOU HEAD FURTHER NORTH...AND CANNOT RULE OUT OUTFLOWS
FROM WISCONSIN SINKING SOUTH AND KICKING OFF A FEW THUNDERSTORMS...
PARTICULARLY IN THE NORTHERN COUNTIES OF THE CWA. IF THIS WERE TO
OCCUR...40-50KT DEEP LAYER SHEAR ALONG WITH THE MODERATE INSTABILITY
WOULD BE MORE THAN SUFFICIENT TO SUPPORT A SEVERE THREAT.
THIS EVENING THROUGH SUNDAY TONIGHT...
LOW PRESSURE WILL BE CENTERED OVER THE OKLAHOMA/TEXAS PANHANDLE
REGION WITH AN ELONGATED TROUGH EXTENDING NORTHEAST INTO SOUTHERN
WISCONSIN THEN INTO THE EASTERN GREAT LAKES WHICH WILL SERVE THE
FOCUS FOR MOST OF THE OVERNIGHT CONVECTION. BROAD SOUTHERLY FLOW
AHEAD OF THE OF TROUGH WILL RESULT IN CONTINUED MOISTENING OF THE
COLUMN WITH PWATS RISING TO AROUND 1.2-1.3 INCHES OR SO OVERNIGHT.
IN ADDITION...AN AXIS OF AROUND 1000 J/KG MUCAPE NEAR THE TROUGH
AXIS WILL EXTEND INTO PORTIONS OF NORTH CENTRAL ILLINOIS. BROAD
WARM/MOIST ADVECTION INTO THE REGION AS WELL AS WELL AS MODERATE
DIVERGENCE ALOFT ASSOCIATED WITH RIGHT ENTRANCE REGION OF THE JET
SHOULD PROVIDE SUFFICIENT ASCENT FOR CONVECTION TO FIRE ALONG AND
AHEAD OF THE TROUGH AXIS DURING THE LATE EVENING AND EARLY OVERNIGHT
WHICH WILL THEN SLOWLY SAG SOUTH INTO THE CWA. MEANWHILE...A LOW
LEVEL JET WILL DEVELOP OVER OKLAHOMA WITH THE BEST CONVERGENCE
FOCUSED ACROSS PORTIONS OF NORTHERN MISSOURI/IOWA. EXPECT THIS AREA
TO BECOME THE MAIN SHOW WITH AN MCS DEVELOPING IN UNSTABLE AND
MODERATELY SHEARED ENVIRONMENT...POSSIBLY EVEN CUTTING OFF ACCESS TO
THE SOME OF THE ENERGY TRANSPORT INTO OUR AREA WHICH WOULD THEN
RESULT IN A LULL IN THE PRECIP OVER OUR AREA LATER IN THE OVERNIGHT
HOURS. ANY MCS DEVELOPING OVER NORTHERN MISSOURI WOULD EVENTUALLY
LIFT NORTHEAST TO OR NEAR THE CWA BUT WOULD LIKELY BE IN A DECAYING
PHASE AS IT REACHES THE LOCAL AREA SUNDAY MORNING.
WITH CONVECTIVE DEBRIS MOVING OVERHEAD IT WILL BE DIFFICULT TO
RECOVER SUNDAY AND EXPECT MAINLY SOME LINGERING SCATTERED SHOWERS
WITH A FEW THUNDERSTORMS POSSIBLE DURING THE EARLY PART OF THE DAY.
MEANWHILE...SOUTHERN STREAM JET ROUNDING THE BASE OF THE LONGWAVE
TROUGH WILL BEGIN TO LIFT TOWARDS THE AREA WITH MODERATE TO STRONG
DIVERGENCE ALOFT DEVELOPING AS COUPLED JET DEVELOPS DURING THE
AFTERNOON RESULTING IN SURFACE CYCLOGENESIS ALONG THE MID
MISSISSIPPI VALLEY. LOW LEVEL JET IS PROGGED TO REDEVELOP SUNDAY
EVENING ACROSS ILLINOIS AND WILL PUSH PWATS UP TO AROUND AN INCH AND
A HALF. INSTABILITY WILL REMAIN MEAGER BUT STRONG DYNAMIC FORCING
SHOULD OFFSET THIS WITH SHOWERS/EMBEDDED THUNDERSTORMS
RE-INTENSIFYING LATE AFTERNOON AND INTO THE EVENING. DEEP LAYER WINDS
PARALLEL TO THE BOUNDARY WILL RESULT IN TRAINING OF HEAVY
SHOWERS/THUNDERSTORMS AND DEEP MOIST SOUNDINGS INDICATE THAT
RAINFALL WILL BE EFFICIENT. GLOBAL MODELS CONTINUE TO PAINT A STRIPE
OF 3 TO IN EXCESS OF 4 INCHES SOMEWHERE IN THE REGION...MOST LIKELY
INCLUDING PORTIONS OF NORTH CENTRAL ILLINOIS. FLOODING REMAINS A
CONCERN AND A HYDROLOGIC OUTLOOK //ESF// WILL BE RE-ISSUED IN THE
MEANTIME...THOUGH A FLOOD WATCH MAY WELL BE NEEDED EVENTUALLY.
THERE WILL BE A BIG BUST POTENTIAL SUNDAY FOR TEMPERATURES DEPENDING
ON WHERE EXACTLY THE FRONTAL BOUNDARY IS AND HOW QUICKLY IT
PROGRESSES WHICH CAN BE IMPACTED BY CONVECTIVE OUTFLOW AS WELL AS
COOL AIR FROM THE LAKE. LIKELY THERE WILL BE A TIGHT TEMPERATURE
CONTRAST SOMEWHERE WITH 70S ON THE WARM SIDE OF THE BOUNDARY AND
40S/50S ON THE COOL SIDE. PRECIP AND CLOUD COVER ADD ADDITIONAL
UNCERTAINTY...AS WELL AS THE POTENTIAL FOR A LAKE BREEZE TO DEVELOP
WITHIN THE WEAKER SYNOPTIC WINDS NEAR THE TROUGH AXIS.
MONDAY THROUGH FRIDAY...
MAIN UPPER TROUGH AXIS WILL PUSH EAST ACROSS THE PLAINS MONDAY WITH
ANOTHER SURFACE WAVE LIFTING FROM THE LOWER MISSISSIPPI VALLEY INTO
THE OHIO VALLEY. H85 TEMPS FALL STEADILY THROUGH THE DAY
MONDAY...EVENTUALLY BOTTOMING OUT AROUND -12C MONDAY NIGHT. BY
MONDAY MORNING...TEMPS ALOFT WILL SUPPORT SNOW FALLING INTO THE
BOUNDARY LAYER...THOUGH DURING THE DAY AT LEAST WITH TEMPS
REBOUNDING INTO THE LOW 40S SHOULD BE ENOUGH TO MELT ANY PRECIP
BEFORE OR AS IT HITS THE SURFACE. BY MONDAY NIGHT THOUGH WITH LOWS
FALLING INTO THE MID TO UPPER 20S...ANY LINGERING PRECIP WILL BE
SNOW. WEATHER SHOULD BE FAIRLY QUIET TUESDAY AND WEDNESDAY UNDER THE
INFLUENCE OF HIGH PRESSURE WITH WARMER AIR STARTING TO SPREAD BACK
INTO THE AREA LATER ON WEDNESDAY. CHANCES FOR RAIN RETURN LATE IN
THE WEEK.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* CLUSTER OF STRONG/SEVERE TSRA OVER FAR NORTHEAST IL EXPECTED TO
CONTNUE TO TRACK EAST NEXT 1-2 HRS...PASSING A FEW MILES NORTH
OF DPA/ORD PROPER.
* SOUTH WINDS 15-20 KT BY LATE MORNING WITH GUSTS 25KT DURING THE
AFTERNOON. WINDS THEN EASING OFF AROUND SUNSET.
* CHANCE OF THUNDERSTORMS LATER THIS EVENING.
* MORE WIDESPREAD RAIN DEVELOPING LATER SUNDAY MORNING WITH MVFR
CONDITIONS DEVELOPING.
RATZER
//DISCUSSION...UPDATED 12Z...
A WEAK WARM FRONT LYING WEST TO EAST ACROSS EXTREME NORTHERN IL AT
11 UTC WILL MOVE ONLY VERY SLOWLY NORTH TODAY AS RAIN AND EMBEDDED
THUNDERSHOWERS MOVE EAST OUT OF IOWA ALONG AND NORTH OF THE FRONT
THIS MORNING. AS THIS AREA OF PRECIP MOVES FARTHER EAST INTO
DEEPER DRIER AIR AND AWAY FROM WHAT LITTLE INSTABILITY THERE IS
BACK TO THE WEST... EXPECT IT TO FALL APART.
WITH LOW PRESSURE OVER SOUTH DAKOTA MOVING INTO IOWA LATER IN
THE DAY... WINDS WILL INCREASE OUT OF THE SOUTH WITH GUSTS FROM
LATE MORNING THROUGH EARLY EVENING. WARM MOIST AIR WILL SURGE
NORTHWARD INTO THE AREA LATER TODAY VIA THESE BRISK SOUTH WINDS
AND HELP FUEL SHOWER AND THUNDERSTORMS ALONG AND NORTH OF THE WARM
FRONT ASSOCIATED WITH THE AFOREMENTIONED LOW PRESSURE SYSTEM...
BUT MOSTLY LIKELY STAYING NORTH AND WEST OF ORD/MDW THROUGH THE
DAYLIGHT HOURS.
BETTER FORCING FOR RAIN AND THUNDERSTORMS COMES TOGETHER ACROSS THE
AREA LATER THIS EVENING AND INTO THE OVERNIGHT. EXPECT SHOWERS AND
THUNDERSTORMS TO SPREAD FURTHER SOUTH AND EAST POTENTIALLY IMPACTING
THE TERMINALS FOR A PERIOD SOMETIME FROM MID EVENING INTO THE
OVERNIGHT. EXACT TIMING DIFFICULT TO PIN DOWN THIS FAR OUT
STILL... BUT WINDOW OF BETTER INSTABILITY APPEARS TO IMPACT
ORD/MDW BETWEEN 04-08Z. MORE WIDESPREAD RAIN WILL DEVELOP AFTER
DAYBREAK SUNDAY... LOWERING CONDITIONS TO MVFR... AND POSSIBLY IFR
FOR A PERIOD LATER.
ED F
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM-HIGH CONFIDNECE IN TSRA TRACKING NORTH OF ORD THROUGH
LATE MORNING.
* HIGH CONFIDENCE IN SOUTH WINDS INCREASING IN SPEED BY LATE MORNING
TODAY... GUSTING DURING THE AFTERNOON.
* LOW CONFIDENCE IN TIMING AND LOCATION OF THUNDERSTORMS THIS
EVENING AND OVERNIGHT.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED
12Z...
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY NIGHT...PERIODS OF SHRA/TSRA. IFR POSSIBLE.
MONDAY...MVFR LIKELY...IFR POSSIBLE. CHANCE OF RAIN.
TUESDAY THROUGH THURSDAY...FAIR WEATHER - VFR EXPECTED.
FRIDAY...CHANCE OF RAIN.
ED F
&&
.MARINE...
325 AM CDT
COMPLEX WEATHER PATTERN TO IMPACT LAKE MICHIGAN THE NEXT 3 DAYS...
AND THE BEST INFORMATION WILL BE OBTAINED VIA GRAPHICS ON THE GREAT
LAKES WEB PORTAL RATHER THAN THE LEGACY GLF TEXT WHERE THE RICHNESS
OF ALL THE INFORMATION CAN MORE READILY BE DECIPHERED. WINDS WILL
INCREASE ACROSS THE LAKE TODAY IN ADVANCE OF LOW PRESSURE
APPROACHING THE AREA FROM THE CENTRAL PLAINS. A WEAK FRONTAL
BOUNDARY LIFTING BACK NORTH AS A WARM FRONT THIS MORNING WILL
SEPARATE SOUTH WINDS TO THE SOUTH FROM SOUTHEAST TO EAST WINDS
CENTRAL AND NORTH. AS THE PLAINS LOW REACHES LAKE MICHIGAN TONIGHT
IT WILL DRAPE A FRONTAL BOUNDARY ACROSS THE CENTRAL AND SOUTHERN
PART OF THE LAKE. AS WE MOVE INTO SUNDAY... YET ANOTHER AREA OF LOW
PRESSURE WILL LIFT NORTHEAST ALONG THE BOUNDARY AND REACH SOUTHERN
LAKE MICHIGAN BY LATE SUNDAY NIGHT.
A PERIOD OF NORTHERLY GALES IS EXPECTED TO DEVELOP BEHIND THIS LOW
PRESSURE AREA AS IT MOVES AWAY FROM THE AREA LATER SUNDAY NIGHT AND
MONDAY. GALE WIND THRESHOLDS MAY FIRST BE SURPASSED ACROSS THE
CENTRAL PART OF THE LAKE WHERE THE GRADIENT TIGHTENS MOST INITIALLY
AND WHERE THERMAL INSTABILITY IS MAXIMIZED. GALE FORCE WINDS WILL
SPREAD SOUTH EARLY MONDAY... AND MAY BE ALSO EXPERIENCED ACROSS THE
NORTH THIRD OF THE LAKE LATER MONDAY AS THE LOW PULLS AWAY.
BROAD HIGH PRESSURE WILL MOVE OVER THE LAKE LATER TUESDAY INTO
WEDNESDAY... BUT THIS PERIOD OF CALMER CONDITIONS WILL NOT BE LONG
LASTING AS THE GRADIENT INCREASES AGAIN AHEAD OF INVERTED LOW
PRESSURE ON THURSDAY.
ED F
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 4 AM SUNDAY.
SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 10 PM SATURDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
1045 AM CDT Sat Apr 12 2014
.DISCUSSION...
ISSUED 1045 AM CDT Sat Apr 12 2014
Forecast generally looks good today and only needed to lower the
amount of cloud cover this morning. Partly to mostly cloudy skies
earlier this morning have become mostly sunny by late morning as
warm front lifted ne of central IL with strong to severe
thunderstorms with hail east of Rockford moving east at 45 mph
toward McHenry county IL. Partly to mostly sunny skies expected
this afternoon with clouds increasing this afternoon especially
over the IL river valley where mostly cloudy skies by sunset.
Showers and thunderstorms should stay north of central IL through
sunset and will keep a dry forecast. Warmer highs in the upper 70s
to near 80F still on track with strong south winds 15 to 25 mph
and gusts of 25 to 35 mph ahead of 1002 mb low pressure over
eastern NE and central KS that deepens to 996 mb by sunset.
07
&&
.AVIATION...
ISSUED 630 AM CDT Sat Apr 12 2014
Southerly winds will ramp up quickly this morning as mixing takes
place, with gusts of 25-30 knots likely by late morning,
continuing into the afternoon. The gusts should begin to drop off
early this evening, but sustained winds of 10-15 knots still
likely through the night. Will need to watch for potential for
LLWS, with some of the models hinting at some borderline LLWS
conditions by mid evening, but will hold off on including it for
now. Ceilings so far today have been VFR, but as low as around
4000 feet near KDEC. HRRR guidance continues to suggest a period
of around 3500 feet through late morning, before rising toward
early afternoon.
Shower and thunderstorm trends are more uncertain, as the incoming
cold front slows a bit. Latest model guidance suggests the period
after 06Z is most likely to see anything, but the showers/storms
that will develop west of the Mississippi River this evening will
likely be breaking up as they approach central Illinois. Have
included some VCSH mention at KPIA/KBMI/KSPI for late in the TAF
period, but kept it dry further east.
Geelhart
&&
.PREV DISCUSSION...
ISSUED 306 AM CDT Sat Apr 12 2014
SHORT TERM...Today through Monday
A windy and very warm day is in store across central Illinois
today. An old frontal boundary currently draped across central
Missouri into the Ohio River Valley will lift rapidly northward
this morning, bringing increasing southerly winds and low-level
moisture. Impressive dew point gradient currently evident across
the region, with middle 30s observed north of the boundary across
central Illinois rising to the lower to middle 50s south of the
front across southern Missouri into western Kentucky. Thanks to
a tightening pressure gradient, strong southerly winds will
transport this moisture northward into central Illinois this
afternoon, pushing DEWPOINTS into the middle to upper 50s.
Forecast soundings and BUFKIT data suggest wind gusts of 30 to
35mph later today. With partly sunny skies and strong southerly
flow, high temperatures will be a couple of degrees warmer than
yesterday, with most locations topping out in the middle to upper
70s.
Two upper air features will play a major role in the weather
across the Midwest over the next 48 hours. The first is a cut-off
low currently spinning over southern California, and the second is
a northern stream wave dropping southeastward toward the northern
Rockies. As the cut-off low opens up and is ejected eastward,
surface cyclogenesis will take place over the Oklahoma panhandle
later today into tonight. Increasing LLJ ahead of the approaching
low will allow convection to blossom within the strongest
instability axis across Kansas into central/northern Iowa late
this afternoon/evening. While decent CAPE values of around
1000J/kg will develop further east across central Illinois today,
forecast soundings show a strong cap at around 750mb. Due to the
capped air mass and lack of strong forcing, will go with a dry
forecast across the board through this afternoon. As surface low
and its associated frontal boundary slowly edge eastward,
showers/storms will begin to develop across the western KILX CWA
tonight. Models have trended slower with the eastward spread of
the precip, so will confine PoPs to locations along/west of the
I-55 corridor. System makes only slow progress eastward on Sunday,
with NAM/GFS/ECMWF showing little or no precip across the far
E/SE. Have made a few adjustments to PoPs in order to account for
the slowing trend, with areas along/south of I-70 remaining dry
throughout the day Sunday. Further west, will go with categorical
PoPs in the Illinois River Valley in closer proximity to strongest
forcing. Will be another very warm day, with highs ranging from
the rain-cooled upper 60s west of the Illinois River to the upper
70s far SE.
Best rain chances arrive Sunday night as initial upper wave pushes
cold front into the area. With strong convergence along the
surface front, ample support aloft, and precipitable water values
climbing to around 1.50, widespread showers and thunderstorms are
a good bet. Locally heavy rainfall will be likely as well. Cold
front will push into Indiana by Monday morning, resulting in windy
and sharply colder conditions. High temperatures will only be in
the 40s across much of the area, with early morning highs in the
upper 50s to around 60 across the Wabash River Valley dropping
into the 40s as the day progresses. In addition, all models
indicate lingering showers well behind the boundary as northern
stream upper wave arrives. Big question will be whether or not any
moisture can linger long enough to change to snow Monday night as
850mb temps drop into the -4 to -8C range and surface temps drop
into the upper 20s/lower 30s. At this point, the NAM is the only
model that is showing snow across central Illinois, as it develops
a secondary low along the departing cold front. GFS/ECMWF/GEM do
not develop this feature and thus bring the precip to an end
before the air mass cools sufficiently for snow. As a result, will
only carry a slight chance for rain showers during the evening
across the E/SE CWA, followed by cold and dry weather overnight.
LONG TERM...Tuesday through Friday
Mainly quiet weather can be expected in the extended, with a
gradual warm-up. Rising upper heights will allow chilly temps in
the 40s on Tuesday to recover into the 60s by Thursday and Friday.
Models are having trouble resolving the next potential system to
impact the region by the end of next week, with the GFS being much
more aggressive with precip Thursday night into Friday. Due to
discrepancies this far out, will only mention a slight chance for
showers on Friday until better consensus is reached.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
645 AM CDT SAT APR 12 2014
.DISCUSSION...
306 AM CDT
TODAY...
THIS MORNING...LOW PRESSURE IS CENTERED OVER SOUTH DAKOTA WHILE A
WARM FRONT STRETCHES EAST ACROSS CENTRAL IOWA TO NEAR ROCHELLE AND
EAST INTO CHICAGO. THE WARM FRONT WILL LIFT NORTH INTO WISCONSIN
BY LATE THIS MORNING. WEAK CONVECTION HAS DEVELOPED ACROSS
NORTHWESTERN IOWA EARLY THIS MORNING AND IS PROGGED TO MOVE ALONG
THE IL/WI STATE LINE THIS MORNING...THOUGH SHOULD DISSIPATE AS IT
OUTRUNS THE MEAGER INSTABILITY CURRENTLY IN PLACE TO OUR WEST. AS
THE WARM FRONT LIFTS NORTH OF THE AREA TODAY...MID 50 DEWPOINTS IN
PLACE ACROSS FAR DOWNSTATE ILLINOIS WILL ALSO OVERSPREAD THE
AREA...ACCOMPANIED BY TEMPERATURES EXPECTED TO PUSH INTO MID TO
UPPER 70S RESULTING IN MODERATE SURFACE BASED INSTABILITY DEVELOPING
THIS AFTERNOON. MLCAPE VALUES IN EXCESS OF 1000 J/KG ARE EXPECTED
ESPECIALLY IN THE WESTERN COUNTIES THIS AFTERNOON...THOUGH SHOULD
REMAIN CAPPED AS THE BEST FORCING WILL BE TO OUR NORTH. THE CAPPING
DOES ERODE AS YOU HEAD FURTHER NORTH...AND CANNOT RULE OUT OUTFLOWS
FROM WISCONSIN SINKING SOUTH AND KICKING OFF A FEW THUNDERSTORMS...
PARTICULARLY IN THE NORTHERN COUNTIES OF THE CWA. IF THIS WERE TO
OCCUR...40-50KT DEEP LAYER SHEAR ALONG WITH THE MODERATE INSTABILITY
WOULD BE MORE THAN SUFFICIENT TO SUPPORT A SEVERE THREAT.
THIS EVENING THROUGH SUNDAY TONIGHT...
LOW PRESSURE WILL BE CENTERED OVER THE OKLAHOMA/TEXAS PANHANDLE
REGION WITH AN ELONGATED TROUGH EXTENDING NORTHEAST INTO SOUTHERN
WISCONSIN THEN INTO THE EASTERN GREAT LAKES WHICH WILL SERVE THE
FOCUS FOR MOST OF THE OVERNIGHT CONVECTION. BROAD SOUTHERLY FLOW
AHEAD OF THE OF TROUGH WILL RESULT IN CONTINUED MOISTENING OF THE
COLUMN WITH PWATS RISING TO AROUND 1.2-1.3 INCHES OR SO OVERNIGHT.
IN ADDITION...AN AXIS OF AROUND 1000 J/KG MUCAPE NEAR THE TROUGH
AXIS WILL EXTEND INTO PORTIONS OF NORTH CENTRAL ILLINOIS. BROAD
WARM/MOIST ADVECTION INTO THE REGION AS WELL AS WELL AS MODERATE
DIVERGENCE ALOFT ASSOCIATED WITH RIGHT ENTRANCE REGION OF THE JET
SHOULD PROVIDE SUFFICIENT ASCENT FOR CONVECTION TO FIRE ALONG AND
AHEAD OF THE TROUGH AXIS DURING THE LATE EVENING AND EARLY OVERNIGHT
WHICH WILL THEN SLOWLY SAG SOUTH INTO THE CWA. MEANWHILE...A LOW
LEVEL JET WILL DEVELOP OVER OKLAHOMA WITH THE BEST CONVERGENCE
FOCUSED ACROSS PORTIONS OF NORTHERN MISSOURI/IOWA. EXPECT THIS AREA
TO BECOME THE MAIN SHOW WITH AN MCS DEVELOPING IN UNSTABLE AND
MODERATELY SHEARED ENVIRONMENT...POSSIBLY EVEN CUTTING OFF ACCESS TO
THE SOME OF THE ENERGY TRANSPORT INTO OUR AREA WHICH WOULD THEN
RESULT IN A LULL IN THE PRECIP OVER OUR AREA LATER IN THE OVERNIGHT
HOURS. ANY MCS DEVELOPING OVER NORTHERN MISSOURI WOULD EVENTUALLY
LIFT NORTHEAST TO OR NEAR THE CWA BUT WOULD LIKELY BE IN A DECAYING
PHASE AS IT REACHES THE LOCAL AREA SUNDAY MORNING.
WITH CONVECTIVE DEBRIS MOVING OVERHEAD IT WILL BE DIFFICULT TO
RECOVER SUNDAY AND EXPECT MAINLY SOME LINGERING SCATTERED SHOWERS
WITH A FEW THUNDERSTORMS POSSIBLE DURING THE EARLY PART OF THE DAY.
MEANWHILE...SOUTHERN STREAM JET ROUNDING THE BASE OF THE LONGWAVE
TROUGH WILL BEGIN TO LIFT TOWARDS THE AREA WITH MODERATE TO STRONG
DIVERGENCE ALOFT DEVELOPING AS COUPLED JET DEVELOPS DURING THE
AFTERNOON RESULTING IN SURFACE CYCLOGENESIS ALONG THE MID
MISSISSIPPI VALLEY. LOW LEVEL JET IS PROGGED TO REDEVELOP SUNDAY
EVENING ACROSS ILLINOIS AND WILL PUSH PWATS UP TO AROUND AN INCH AND
A HALF. INSTABILITY WILL REMAIN MEAGER BUT STRONG DYNAMIC FORCING
SHOULD OFFSET THIS WITH SHOWERS/EMBEDDED THUNDERSTORMS
RE-INTENSIFYING LATE AFTERNOON AND INTO THE EVENING. DEEP LAYER WINDS
PARALLEL TO THE BOUNDARY WILL RESULT IN TRAINING OF HEAVY
SHOWERS/THUNDERSTORMS AND DEEP MOIST SOUNDINGS INDICATE THAT
RAINFALL WILL BE EFFICIENT. GLOBAL MODELS CONTINUE TO PAINT A STRIPE
OF 3 TO IN EXCESS OF 4 INCHES SOMEWHERE IN THE REGION...MOST LIKELY
INCLUDING PORTIONS OF NORTH CENTRAL ILLINOIS. FLOODING REMAINS A
CONCERN AND A HYDROLOGIC OUTLOOK //ESF// WILL BE RE-ISSUED IN THE
MEANTIME...THOUGH A FLOOD WATCH MAY WELL BE NEEDED EVENTUALLY.
THERE WILL BE A BIG BUST POTENTIAL SUNDAY FOR TEMPERATURES DEPENDING
ON WHERE EXACTLY THE FRONTAL BOUNDARY IS AND HOW QUICKLY IT
PROGRESSES WHICH CAN BE IMPACTED BY CONVECTIVE OUTFLOW AS WELL AS
COOL AIR FROM THE LAKE. LIKELY THERE WILL BE A TIGHT TEMPERATURE
CONTRAST SOMEWHERE WITH 70S ON THE WARM SIDE OF THE BOUNDARY AND
40S/50S ON THE COOL SIDE. PRECIP AND CLOUD COVER ADD ADDITIONAL
UNCERTAINTY...AS WELL AS THE POTENTIAL FOR A LAKE BREEZE TO DEVELOP
WITHIN THE WEAKER SYNOPTIC WINDS NEAR THE TROUGH AXIS.
MONDAY THROUGH FRIDAY...
MAIN UPPER TROUGH AXIS WILL PUSH EAST ACROSS THE PLAINS MONDAY WITH
ANOTHER SURFACE WAVE LIFTING FROM THE LOWER MISSISSIPPI VALLEY INTO
THE OHIO VALLEY. H85 TEMPS FALL STEADILY THROUGH THE DAY
MONDAY...EVENTUALLY BOTTOMING OUT AROUND -12C MONDAY NIGHT. BY
MONDAY MORNING...TEMPS ALOFT WILL SUPPORT SNOW FALLING INTO THE
BOUNDARY LAYER...THOUGH DURING THE DAY AT LEAST WITH TEMPS
REBOUNDING INTO THE LOW 40S SHOULD BE ENOUGH TO MELT ANY PRECIP
BEFORE OR AS IT HITS THE SURFACE. BY MONDAY NIGHT THOUGH WITH LOWS
FALLING INTO THE MID TO UPPER 20S...ANY LINGERING PRECIP WILL BE
SNOW. WEATHER SHOULD BE FAIRLY QUIET TUESDAY AND WEDNESDAY UNDER THE
INFLUENCE OF HIGH PRESSURE WITH WARMER AIR STARTING TO SPREAD BACK
INTO THE AREA LATER ON WEDNESDAY. CHANCES FOR RAIN RETURN LATE IN
THE WEEK.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* SOUTH WINDS INCREASING ABOVE 10 KT THIS MORNING AND TO 15-20 KT
BY LATE MORNING WITH GUSTS 25KT DURING THE AFTERNOON. WINDS
THEN EASING OFF AROUND SUNSET.
* CHANCE OF THUNDERSTORMS LATER THIS EVENING.
* MORE WIDESPREAD RAIN DEVELOPING LATER SUNDAY MORNING WITH MVFR
CONDITIONS DEVELOPING.
ED F
//DISCUSSION...UPDATED 12Z...
A WEAK WARM FRONT LYING WEST TO EAST ACROSS EXTREME NORTHERN IL AT
11 UTC WILL MOVE ONLY VERY SLOWLY NORTH TODAY AS RAIN AND EMBEDDED
THUNDERSHOWERS MOVE EAST OUT OF IOWA ALONG AND NORTH OF THE FRONT
THIS MORNING. AS THIS AREA OF PRECIP MOVES FARTHER EAST INTO
DEEPER DRIER AIR AND AWAY FROM WHAT LITTLE INSTABILITY THERE IS
BACK TO THE WEST... EXPECT IT TO FALL APART.
WITH LOW PRESSURE OVER SOUTH DAKOTA MOVING INTO IOWA LATER IN
THE DAY... WINDS WILL INCREASE OUT OF THE SOUTH WITH GUSTS FROM
LATE MORNING THROUGH EARLY EVENING. WARM MOIST AIR WILL SURGE
NORTHWARD INTO THE AREA LATER TODAY VIA THESE BRISK SOUTH WINDS
AND HELP FUEL SHOWER AND THUNDERSTORMS ALONG AND NORTH OF THE WARM
FRONT ASSOCIATED WITH THE AFOREMENTIONED LOW PRESSURE SYSTEM...
BUT MOSTLY LIKELY STAYING NORTH AND WEST OF ORD/MDW THROUGH THE
DAYLIGHT HOURS.
BETTER FORCING FOR RAIN AND THUNDERSTORMS COMES TOGETHER ACROSS THE
AREA LATER THIS EVENING AND INTO THE OVERNIGHT. EXPECT SHOWERS AND
THUNDERSTORMS TO SPREAD FURTHER SOUTH AND EAST POTENTIALLY IMPACTING
THE TERMINALS FOR A PERIOD SOMETIME FROM MID EVENING INTO THE
OVERNIGHT. EXACT TIMING DIFFICULT TO PIN DOWN THIS FAR OUT
STILL... BUT WINDOW OF BETTER INSTABILITY APPEARS TO IMPACT
ORD/MDW BETWEEN 04-08Z. MORE WIDESPREAD RAIN WILL DEVELOP AFTER
DAYBREAK SUNDAY... LOWERING CONDITIONS TO MVFR... AND POSSIBLY IFR
FOR A PERIOD LATER.
ED F
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* HIGH CONFIDENCE IN SOUTH WINDS INCREASING IN SPEED BY LATE
MORNING TODAY... GUSTING DURING THE AFTERNOON.
* LOW CONFIDENCE IN TIMING AND LOCATION OF THUNDERSTORMS THIS
EVENING AND OVERNIGHT.
ED F
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY NIGHT...PERIODS OF SHRA/TSRA. IFR POSSIBLE.
MONDAY...MVFR LIKELY...IFR POSSIBLE. CHANCE OF RAIN.
TUESDAY THROUGH THURSDAY...FAIR WEATHER - VFR EXPECTED.
FRIDAY...CHANCE OF RAIN.
ED F
&&
.MARINE...
325 AM CDT
COMPLEX WEATHER PATTERN TO IMPACT LAKE MICHIGAN THE NEXT 3 DAYS...
AND THE BEST INFORMATION WILL BE OBTAINED VIA GRAPHICS ON THE GREAT
LAKES WEB PORTAL RATHER THAN THE LEGACY GLF TEXT WHERE THE RICHNESS
OF ALL THE INFORMATION CAN MORE READILY BE DECIPHERED. WINDS WILL
INCREASE ACROSS THE LAKE TODAY IN ADVANCE OF LOW PRESSURE
APPROACHING THE AREA FROM THE CENTRAL PLAINS. A WEAK FRONTAL
BOUNDARY LIFTING BACK NORTH AS A WARM FRONT THIS MORNING WILL
SEPARATE SOUTH WINDS TO THE SOUTH FROM SOUTHEAST TO EAST WINDS
CENTRAL AND NORTH. AS THE PLAINS LOW REACHES LAKE MICHIGAN TONIGHT
IT WILL DRAPE A FRONTAL BOUNDARY ACROSS THE CENTRAL AND SOUTHERN
PART OF THE LAKE. AS WE MOVE INTO SUNDAY... YET ANOTHER AREA OF LOW
PRESSURE WILL LIFT NORTHEAST ALONG THE BOUNDARY AND REACH SOUTHERN
LAKE MICHIGAN BY LATE SUNDAY NIGHT.
A PERIOD OF NORTHERLY GALES IS EXPECTED TO DEVELOP BEHIND THIS LOW
PRESSURE AREA AS IT MOVES AWAY FROM THE AREA LATER SUNDAY NIGHT AND
MONDAY. GALE WIND THRESHOLDS MAY FIRST BE SURPASSED ACROSS THE
CENTRAL PART OF THE LAKE WHERE THE GRADIENT TIGHTENS MOST INITIALLY
AND WHERE THERMAL INSTABILITY IS MAXIMIZED. GALE FORCE WINDS WILL
SPREAD SOUTH EARLY MONDAY... AND MAY BE ALSO EXPERIENCED ACROSS THE
NORTH THIRD OF THE LAKE LATER MONDAY AS THE LOW PULLS AWAY.
BROAD HIGH PRESSURE WILL MOVE OVER THE LAKE LATER TUESDAY INTO
WEDNESDAY... BUT THIS PERIOD OF CALMER CONDITIONS WILL NOT BE LONG
LASTING AS THE GRADIENT INCREASES AGAIN AHEAD OF INVERTED LOW
PRESSURE ON THURSDAY.
ED F
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...10 AM SATURDAY TO
4 AM SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...10 AM SATURDAY TO
10 PM SATURDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
630 AM CDT Sat Apr 12 2014
.DISCUSSION...
ISSUED 306 AM CDT Sat Apr 12 2014
SHORT TERM...Today through Monday
A windy and very warm day is in store across central Illinois
today. An old frontal boundary currently draped across central
Missouri into the Ohio River Valley will lift rapidly northward
this morning, bringing increasing southerly winds and low-level
moisture. Impressive dew point gradient currently evident across
the region, with middle 30s observed north of the boundary across
central Illinois rising to the lower to middle 50s south of the
front across southern Missouri into western Kentucky. Thanks to
a tightening pressure gradient, strong southerly winds will
transport this moisture northward into central Illinois this
afternoon, pushing DEWPOINTS into the middle to upper 50s.
Forecast soundings and BUFKIT data suggest wind gusts of 30 to
35mph later today. With partly sunny skies and strong southerly
flow, high temperatures will be a couple of degrees warmer than
yesterday, with most locations topping out in the middle to upper
70s.
Two upper air features will play a major role in the weather
across the Midwest over the next 48 hours. The first is a cut-off
low currently spinning over southern California, and the second is
a northern stream wave dropping southeastward toward the northern
Rockies. As the cut-off low opens up and is ejected eastward,
surface cyclogenesis will take place over the Oklahoma panhandle
later today into tonight. Increasing LLJ ahead of the approaching
low will allow convection to blossom within the strongest
instability axis across Kansas into central/northern Iowa late
this afternoon/evening. While decent CAPE values of around
1000J/kg will develop further east across central Illinois today,
forecast soundings show a strong cap at around 750mb. Due to the
capped air mass and lack of strong forcing, will go with a dry
forecast across the board through this afternoon. As surface low
and its associated frontal boundary slowly edge eastward,
showers/storms will begin to develop across the western KILX CWA
tonight. Models have trended slower with the eastward spread of
the precip, so will confine PoPs to locations along/west of the
I-55 corridor. System makes only slow progress eastward on Sunday,
with NAM/GFS/ECMWF showing little or no precip across the far
E/SE. Have made a few adjustments to PoPs in order to account for
the slowing trend, with areas along/south of I-70 remaining dry
throughout the day Sunday. Further west, will go with categorical
PoPs in the Illinois River Valley in closer proximity to strongest
forcing. Will be another very warm day, with highs ranging from
the rain-cooled upper 60s west of the Illinois River to the upper
70s far SE.
Best rain chances arrive Sunday night as initial upper wave pushes
cold front into the area. With strong convergence along the
surface front, ample support aloft, and precipitable water values
climbing to around 1.50, widespread showers and thunderstorms are
a good bet. Locally heavy rainfall will be likely as well. Cold
front will push into Indiana by Monday morning, resulting in windy
and sharply colder conditions. High temperatures will only be in
the 40s across much of the area, with early morning highs in the
upper 50s to around 60 across the Wabash River Valley dropping
into the 40s as the day progresses. In addition, all models
indicate lingering showers well behind the boundary as northern
stream upper wave arrives. Big question will be whether or not any
moisture can linger long enough to change to snow Monday night as
850mb temps drop into the -4 to -8C range and surface temps drop
into the upper 20s/lower 30s. At this point, the NAM is the only
model that is showing snow across central Illinois, as it develops
a secondary low along the departing cold front. GFS/ECMWF/GEM do
not develop this feature and thus bring the precip to an end
before the air mass cools sufficiently for snow. As a result, will
only carry a slight chance for rain showers during the evening
across the E/SE CWA, followed by cold and dry weather overnight.
LONG TERM...Tuesday through Friday
Mainly quiet weather can be expected in the extended, with a
gradual warm-up. Rising upper heights will allow chilly temps in
the 40s on Tuesday to recover into the 60s by Thursday and Friday.
Models are having trouble resolving the next potential system to
impact the region by the end of next week, with the GFS being much
more aggressive with precip Thursday night into Friday. Due to
discrepancies this far out, will only mention a slight chance for
showers on Friday until better consensus is reached.
Barnes
&&
.AVIATION...
ISSUED 630 AM CDT Sat Apr 12 2014
Southerly winds will ramp up quickly this morning as mixing takes
place, with gusts of 25-30 knots likely by late morning,
continuing into the afternoon. The gusts should begin to drop off
early this evening, but sustained winds of 10-15 knots still
likely through the night. Will need to watch for potential for
LLWS, with some of the models hinting at some borderline LLWS
conditions by mid evening, but will hold off on including it for
now. Ceilings so far today have been VFR, but as low as around
4000 feet near KDEC. HRRR guidance continues to suggest a period
of around 3500 feet through late morning, before rising toward
early afternoon.
Shower and thunderstorm trends are more uncertain, as the incoming
cold front slows a bit. Latest model guidance suggests the period
after 06Z is most likely to see anything, but the showers/storms
that will develop west of the Mississippi River this evening will
likely be breaking up as they approach central Illinois. Have
included some VCSH mention at KPIA/KBMI/KSPI for late in the TAF
period, but kept it dry further east.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
308 AM CDT SAT APR 12 2014
.DISCUSSION...
306 AM CDT
TODAY...
THIS MORNING...LOW PRESSURE IS CENTERED OVER SOUTH DAKOTA WHILE A
WARM FRONT STRETCHES EAST ACROSS CENTRAL IOWA TO NEAR ROCHELLE AND
EAST INTO CHICAGO. THE WARM FRONT WILL LIFT NORTH INTO WISCONSIN
BY LATE THIS MORNING. WEAK CONVECTION HAS DEVELOPED ACROSS
NORTHWESTERN IOWA EARLY THIS MORNING AND IS PROGGED TO MOVE ALONG
THE IL/WI STATE LINE THIS MORNING...THOUGH SHOULD DISSIPATE AS IT
OUTRUNS THE MEAGER INSTABILITY CURRENTLY IN PLACE TO OUR WEST. AS
THE WARM FRONT LIFTS NORTH OF THE AREA TODAY...MID 50 DEWPOINTS IN
PLACE ACROSS FAR DOWNSTATE ILLINOIS WILL ALSO OVERSPREAD THE
AREA...ACCOMPANIED BY TEMPERATURES EXPECTED TO PUSH INTO MID TO
UPPER 70S RESULTING IN MODERATE SURFACE BASED INSTABILITY DEVELOPING
THIS AFTERNOON. MLCAPE VALUES IN EXCESS OF 1000 J/KG ARE EXPECTED
ESPECIALLY IN THE WESTERN COUNTIES THIS AFTERNOON...THOUGH SHOULD
REMAIN CAPPED AS THE BEST FORCING WILL BE TO OUR NORTH. THE CAPPING
DOES ERODE AS YOU HEAD FURTHER NORTH...AND CANNOT RULE OUT OUTFLOWS
FROM WISCONSIN SINKING SOUTH AND KICKING OFF A FEW THUNDERSTORMS...
PARTICULARLY IN THE NORTHERN COUNTIES OF THE CWA. IF THIS WERE TO
OCCUR...40-50KT DEEP LAYER SHEAR ALONG WITH THE MODERATE INSTABILITY
WOULD BE MORE THAN SUFFICIENT TO SUPPORT A SEVERE THREAT.
THIS EVENING THROUGH SUNDAY TONIGHT...
LOW PRESSURE WILL BE CENTERED OVER THE OKLAHOMA/TEXAS PANHANDLE
REGION WITH AN ELONGATED TROUGH EXTENDING NORTHEAST INTO SOUTHERN
WISCONSIN THEN INTO THE EASTERN GREAT LAKES WHICH WILL SERVE THE
FOCUS FOR MOST OF THE OVERNIGHT CONVECTION. BROAD SOUTHERLY FLOW
AHEAD OF THE OF TROUGH WILL RESULT IN CONTINUED MOISTENING OF THE
COLUMN WITH PWATS RISING TO AROUND 1.2-1.3 INCHES OR SO OVERNIGHT.
IN ADDITION...AN AXIS OF AROUND 1000 J/KG MUCAPE NEAR THE TROUGH
AXIS WILL EXTEND INTO PORTIONS OF NORTH CENTRAL ILLINOIS. BROAD
WARM/MOIST ADVECTION INTO THE REGION AS WELL AS WELL AS MODERATE
DIVERGENCE ALOFT ASSOCIATED WITH RIGHT ENTRANCE REGION OF THE JET
SHOULD PROVIDE SUFFICIENT ASCENT FOR CONVECTION TO FIRE ALONG AND
AHEAD OF THE TROUGH AXIS DURING THE LATE EVENING AND EARLY OVERNIGHT
WHICH WILL THEN SLOWLY SAG SOUTH INTO THE CWA. MEANWHILE...A LOW
LEVEL JET WILL DEVELOP OVER OKLAHOMA WITH THE BEST CONVERGENCE
FOCUSED ACROSS PORTIONS OF NORTHERN MISSOURI/IOWA. EXPECT THIS AREA
TO BECOME THE MAIN SHOW WITH AN MCS DEVELOPING IN UNSTABLE AND
MODERATELY SHEARED ENVIRONMENT...POSSIBLY EVEN CUTTING OFF ACCESS TO
THE SOME OF THE ENERGY TRANSPORT INTO OUR AREA WHICH WOULD THEN
RESULT IN A LULL IN THE PRECIP OVER OUR AREA LATER IN THE OVERNIGHT
HOURS. ANY MCS DEVELOPING OVER NORTHERN MISSOURI WOULD EVENTUALLY
LIFT NORTHEAST TO OR NEAR THE CWA BUT WOULD LIKELY BE IN A DECAYING
PHASE AS IT REACHES THE LOCAL AREA SUNDAY MORNING.
WITH CONVECTIVE DEBRIS MOVING OVERHEAD IT WILL BE DIFFICULT TO
RECOVER SUNDAY AND EXPECT MAINLY SOME LINGERING SCATTERED SHOWERS
WITH A FEW THUNDERSTORMS POSSIBLE DURING THE EARLY PART OF THE DAY.
MEANWHILE...SOUTHERN STREAM JET ROUNDING THE BASE OF THE LONGWAVE
TROUGH WILL BEGIN TO LIFT TOWARDS THE AREA WITH MODERATE TO STRONG
DIVERGENCE ALOFT DEVELOPING AS COUPLED JET DEVELOPS DURING THE
AFTERNOON RESULTING IN SURFACE CYCLOGENESIS ALONG THE MID
MISSISSIPPI VALLEY. LOW LEVEL JET IS PROGGED TO REDEVELOP SUNDAY
EVENING ACROSS ILLINOIS AND WILL PUSH PWATS UP TO AROUND AN INCH AND
A HALF. INSTABILITY WILL REMAIN MEAGER BUT STRONG DYNAMIC FORCING
SHOULD OFFSET THIS WITH SHOWERS/EMBEDDED THUNDERSTORMS
RE-INTENSIFYING LATE AFTERNOON AND INTO THE EVENING. DEEP LAYER WINDS
PARALLEL TO THE BOUNDARY WILL RESULT IN TRAINING OF HEAVY
SHOWERS/THUNDERSTORMS AND DEEP MOIST SOUNDINGS INDICATE THAT
RAINFALL WILL BE EFFICIENT. GLOBAL MODELS CONTINUE TO PAINT A STRIPE
OF 3 TO IN EXCESS OF 4 INCHES SOMEWHERE IN THE REGION...MOST LIKELY
INCLUDING PORTIONS OF NORTH CENTRAL ILLINOIS. FLOODING REMAINS A
CONCERN AND A HYDROLOGIC OUTLOOK //ESF// WILL BE RE-ISSUED IN THE
MEANTIME...THOUGH A FLOOD WATCH MAY WELL BE NEEDED EVENTUALLY.
THERE WILL BE A BIG BUST POTENTIAL SUNDAY FOR TEMPERATURES DEPENDING
ON WHERE EXACTLY THE FRONTAL BOUNDARY IS AND HOW QUICKLY IT
PROGRESSES WHICH CAN BE IMPACTED BY CONVECTIVE OUTFLOW AS WELL AS
COOL AIR FROM THE LAKE. LIKELY THERE WILL BE A TIGHT TEMPERATURE
CONTRAST SOMEWHERE WITH 70S ON THE WARM SIDE OF THE BOUNDARY AND
40S/50S ON THE COOL SIDE. PRECIP AND CLOUD COVER ADD ADDITIONAL
UNCERTAINTY...AS WELL AS THE POTENTIAL FOR A LAKE BREEZE TO DEVELOP
WITHIN THE WEAKER SYNOPTIC WINDS NEAR THE TROUGH AXIS.
MONDAY THROUGH FRIDAY...
MAIN UPPER TROUGH AXIS WILL PUSH EAST ACROSS THE PLAINS MONDAY WITH
ANOTHER SURFACE WAVE LIFTING FROM THE LOWER MISSISSIPPI VALLEY INTO
THE OHIO VALLEY. H85 TEMPS FALL STEADILY THROUGH THE DAY
MONDAY...EVENTUALLY BOTTOMING OUT AROUND -12C MONDAY NIGHT. BY
MONDAY MORNING...TEMPS ALOFT WILL SUPPORT SNOW FALLING INTO THE
BOUNDARY LAYER...THOUGH DURING THE DAY AT LEAST WITH TEMPS
REBOUNDING INTO THE LOW 40S SHOULD BE ENOUGH TO MELT ANY PRECIP
BEFORE OR AS IT HITS THE SURFACE. BY MONDAY NIGHT THOUGH WITH LOWS
FALLING INTO THE MID TO UPPER 20S...ANY LINGERING PRECIP WILL BE
SNOW. WEATHER SHOULD BE FAIRLY QUIET TUESDAY AND WEDNESDAY UNDER THE
INFLUENCE OF HIGH PRESSURE WITH WARMER AIR STARTING TO SPREAD BACK
INTO THE AREA LATER ON WEDNESDAY. CHANCES FOR RAIN RETURN LATE IN
THE WEEK.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* SOUTH WINDS INCREASING ABOVE 10 KT THIS MORNING TO 15-20 KT BY
LATE MORNING WITH GUSTS 25KT+ DURING THE AFTERNOON. WINDS THEN
EASING OFF AROUND SUNSET.
* CHANCE OF THUNDERSTORMS SATURDAY EVENING.
ED F
//DISCUSSION...UPDATED 06Z...
A WEAK COLD FRONT LYING WEST TO EAST ACROSS NORTHERN IL AT 06 UTC WILL
REMAIN NEARLY STATIONARY THE REST OF THE NIGHT BEFORE LIFTING BACK
NORTH AS A WARM FRONT AFTER DAYBREAK SATURDAY. AS LOW PRESSURE
OVER SOUTH DAKOTA MOVES INTO IOWA LATER IN THE DAY... WINDS WILL
INCREASE OUT OF THE SOUTH WITH GUSTS FROM LATE MORNING THROUGH
EARLY EVENING. WARM MOIST AIR WILL SURGE NORTHWARD INTO THE AREA
LATER TODAY VIA THESE BRISK SOUTH WINDS AND HELP FUEL SHOWER AND
THUNDERSTORMS ALONG AND NORTH OF THE WARM FRONT ASSOCIATED WITH
THE AFOREMENTIONED LOW PRESSURE SYSTEM.
CHALLENGING FORECAST AS TO JUST HOW FAR SOUTH SOME OF THIS
CONVECTION MAY BRUSH... HOWEVER AT THIS POINT FEEL ANY RAIN AND
THUNDERSTORMS WILL REMAIN NORTH AND WEST OF THE ORD/MDW TERMINALS
THROUGH THE DAYTIME HOURS UNTIL 00-01 UTC SUNDAY.
ED F
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN STRONG SOUTH WINDS DEVELOPING BY LATE
MORNING SATURDAY... GUSTING DURING THE AFTERNOON.
* LOW CONFIDENCE IN CHANCE OF AND TIMING OF THUNDERSTORMS SATURDAY
EVENING AND OVERNIGHT.
ED F
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY...PERIODS OF SHRA/TSRA. IFR POSSIBLE...ESPECIALLY LATE.
MONDAY...MVFR LIKELY...IFR POSSIBLE. CHANCE OF RAIN.
TUESDAY THROUGH THURSDAY...VFR PROBABLE.
IZZI
&&
.MARINE...
221 PM CDT
A VERY ACTIVE WEATHER PERIOD IS EXPECTED OVER THE LAKE THIS WEEKEND
INTO EARLY NEXT WEEK. A STORM SYSTEM...CURRENT TAKING SHAPE ACROSS
THE NORTHERN HIGH PLAINS...IS EXPECTED TO MOVE OUT ACROSS THE UPPER
MIDWEST ON SATURDAY...THEN MOVE ACROSS THE CENTRAL PORTION OF THE
LAKE SATURDAY NIGHT. THIS LOW LOOKS TO DRAPE A FRONTAL BOUNDARY
SOMEWHERE ACROSS THE CENTRAL AND SOUTHERN SECTIONS OF THE LAKE INTO
SUNDAY...JUST PRIOR TO ANOTHER AREA OF LOW PRESSURE TRANSITIONING
ACROSS NORTHEASTWARD ACROSS SOUTHERN LAKE MICHIGAN ALONG THIS
FRONTAL BOUNDARY SUNDAY NIGHT INTO MONDAY.
OVERALL...THIS WILL RESULT IN A RATHER COMPLEX WIND FORECAST ACROSS
THE LAKE OVER THE NEXT COUPLE OF DAYS...AS THERE WILL BE LIKELY BE
LARGE VARIATIONS IN SPEEDS AND DIRECTIONS ACROSS DIFFERENT SECTIONS
OF THE LAKE. AS IT APPEARS NOW...EASTERLY WINDS WILL BE FAVORED
ACROSS THE NORTHERN 1/3 OF THE LAKE THROUGH SATURDAY
EVENING...BEFORE SHIFTING OUT OF THE NORTH INTO SUNDAY. FARTHER
SOUTH...IT APPEARS AN EASTERLY WIND COMPONENT EARLY SUNDAY WILL
GRADUALLY SHIFT SOUTHEASTERLY...AND EVEN SOUTHERLY BY LATE
SATURDAY...ESPECIALLY ACROSS SOUTHERN LAKE MICHIGAN TO THE SOUTH OF
THE EVOLVING SURFACE BOUNDARY. WIND SPEEDS WILL LIKELY INCREASE
LATER SATURDAY WITH THE APPROACH OF THE FIRST LOW...THIS WILL LIKELY
RESULT IN SMALL CRAFT ADVISORY CONDITIONS FOR THE ILLINOIS AND INDIAN
NEAR SHORES...AS SOUTHERLY WINDS OF 25 TO 30 KT DEVELOP DURING
SATURDAY AFTERNOON AND EVENING.
BY SUNDAY...STRONG NORTHERLY WINDS ARE EXPECTED TO BEGIN DEVELOPING
FROM NORTH TO SOUTH DOWN THE LAKE AS THE SECOND AREA OF LOW PRESSURE
TRACKS ACROSS THE SOUTHERN PORTION OF THE LAKE. ALTHOUGH WINDS
ACROSS THE SOUTH PORTIONS OF THE LAKE MAY BECOME RELATIVELY LIGHT
FOR A PERIOD EARLY ON SUNDAY AS THE LOW APPROACHES...EXPECT
NORTHERLY WINDS TO SET UP AND INCREASE BY SUNDAY NIGHT. IT STILL
APPEARS THE BEST THREAT FOR A PERIOD OF GALES TO 40 KT WILL BE
SUNDAY NIGHT INTO EARLY MONDAY AS COLDER AIR MOVES IN OVER THE LAKE
IN THE WAKE OF THIS AREA OF LOW PRESSURE.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...10 AM SATURDAY TO
4 AM SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...10 AM SATURDAY TO
10 PM SATURDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
306 AM CDT Sat Apr 12 2014
.DISCUSSION...
ISSUED 306 AM CDT Sat Apr 12 2014
SHORT TERM...Today through Monday
A windy and very warm day is in store across central Illinois
today. An old frontal boundary currently draped across central
Missouri into the Ohio River Valley will lift rapidly northward
this morning, bringing increasing southerly winds and low-level
moisture. Impressive dewpoint gradient currently evident across
the region, with middle 30s observed north of the boundary across
central Illinois rising to the lower to middle 50s south of the
front across southern Missouri into western Kentucky. Thanks to
a tightening pressure gradient, strong southerly winds will
transport this moisture northward into central Illinois this
afternoon, pushing dewpoints into the middle to upper 50s.
Forecast soundings and BUFKIT data suggest wind gusts of 30 to
35mph later today. With partly sunny skies and strong southerly
flow, high temperatures will be a couple of degrees warmer than
yesterday, with most locations topping out in the middle to upper
70s.
Two upper air features will play a major role in the weather
across the Midwest over the next 48 hours. The first is a cut-off
low currently spinning over southern California, and the second is
a northern stream wave dropping southeastward toward the northern
Rockies. As the cut-off low opens up and is ejected eastward,
surface cyclogenesis will take place over the Oklahoma panhandle
later today into tonight. Increasing LLJ ahead of the approaching
low will allow convection to blossom within the strongest
instability axis across Kansas into central/northern Iowa late
this afternoon/evening. While decent CAPE values of around
1000J/kg will develop further east across central Illinois today,
forecast soundings show a strong cap at around 750mb. Due to the
capped airmass and lack of strong forcing, will go with a dry
forecast across the board through this afternoon. As surface low
and its associated frontal boundary slowly edge eastward,
showers/storms will begin to develop across the western KILX CWA
tonight. Models have trended slower with the eastward spread of
the precip, so will confine POPs to locations along/west of the
I-55 corridor. System makes only slow progress eastward on Sunday,
with NAM/GFS/ECMWF showing little or no precip across the far
E/SE. Have made a few adjustments to POPs in order to account for
the slowing trend, with areas along/south of I-70 remaining dry
throughout the day Sunday. Further west, will go with categorical
POPs in the Illinois River Valley in closer proximity to strongest
forcing. Will be another very warm day, with highs ranging from
the rain-cooled upper 60s west of the Illinois River to the upper
70s far SE.
Best rain chances arrive Sunday night as initial upper wave pushes
cold front into the area. With strong convergence along the
surface front, ample support aloft, and precipitable water values
climbing to around 1.50, widespread showers and thunderstorms are
a good bet. Locally heavy rainfall will be likely as well. Cold
front will push into Indiana by Monday morning, resulting in windy
and sharply colder conditions. High temperatures will only be in
the 40s across much of the area, with early morning highs in the
upper 50s to around 60 across the Wabash River Valley dropping
into the 40s as the day progresses. In addition, all models
indicate lingering showers well behind the boundary as northern
stream upper wave arrives. Big question will be whether or not any
moisture can linger long enough to change to snow Monday night as
850mb temps drop into the -4 to -8C range and surface temps drop
into the upper 20s/lower 30s. At this point, the NAM is the only
model that is showing snow across central Illinois, as it develops
a secondary low along the departing cold front. GFS/ECMWF/GEM do
not develop this feature and thus bring the precip to an end
before the airmass cools sufficiently for snow. As a result, will
only carry a slight chance for rain showers during the evening
across the E/SE CWA, followed by cold and dry weather overnight.
LONG TERM...Tuesday through Friday
Mainly quiet weather can be expected in the extended, with a
gradual warm-up. Rising upper heights will allow chilly temps in
the 40s on Tuesday to recover into the 60s by Thursday and Friday.
Models are having trouble resolving the next potential system to
impact the region by the end of next week, with the GFS being much
more aggressive with precip Thursday night into Friday. Due to
discrepancies this far out, will only mention a slight chance for
showers on Friday until better consensus is reached.
Barnes
&&
.AVIATION...
ISSUED 1151 PM CDT Fri Apr 11 2014
VFR conditions will prevail at the central and eastern IL TAF
sites for the next 24 hours. It appears that the low level
moisture pushing slowly northward through extreme southern IL is
not expected to be associated with MVFR ceilings. Forecast
soundings and cloud base height forecasts from the HRRR indicate
that the VFR ceilings are expected when the low level moisture
lifts into central IL around and shortly after daybreak.
Still expecting very windy conditions from about mid-morning
into early evening as the pressure gradient increases and plenty
of mixing occurs in the lower atmosphere. BUFKIT momentum transfer
is still indicating the potential for wind gusts to reach 30-35
knots Saturday afternoon.
With the main surface boundary expected to stay along NW and
extreme northern IL, the precipitation will stay to the north of
the TAF sites in central IL through 06Z Sunday. The 00Z model runs
of the NAM and GFS indicate that the rain may even hold off until
later Sunday afternoon.
Miller
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
107 AM CDT SAT APR 12 2014
.DISCUSSION...
338 PM CDT
SHORT TERM...TONIGHT THROUGH MONDAY...
AFTER A QUIET AND PLEASANT DAY TODAY WITH SOME AREAS REGISTERING
THEIR FIRST 70 DEGREE READING OF THE SEASON...AN ACTIVE WEATHER
WEEKEND ON TAP. ON THE DOCKET ARE WINDY WARMTH AND STRONG TO SEVERE
STORM CHANCES ON SATURDAY AND HEAVY RAINFALL ON SUNDAY AND SUNDAY
EVENING THE PRIMARY CONCERNS. MUCH COLDER AIR WILL FILTER IN ON THE
BACKSIDE OF THE SYSTEM THAT WILL IMPACT THE AREA THIS WEEKEND...WITH
SOME CONCERN FOR MIXING WITH SNOW BEFORE THE PRECIPITATION DEPARTS.
TONIGHT...A WEAK SURFACE COLD FRONT WILL DROP SOUTH INTO THE FAR
NORTHERN CWA TONIGHT AND THEN WASH OUT. THE BOUNDARY WILL LIFT BACK
NORTH AS A WARM FRONT ON SATURDAY. AFTER LOWS PRIMARILY IN THE LOWER
AND MID 40S...THIS WARM FRONT LIFTING NORTH WILL SET THE STAGE FOR
THE WARMEST DAY OF THE SEASON ON SATURDAY.
SATURDAY...A TRICKY FORECAST IN THE MORNING THROUGH THE AFTERNOON.
STRONG MOISTURE TRANSPORT WILL SET UP ON THE NOSE OF A ROBUST 850 MB
LOW LEVEL JET...WITH SOME HI-RES GUIDANCE INDICATING FORMATION OF A
CONVECTIVE COMPLEX OVER NW IL/FAR SOUTHERN WI AND MOVING EAST.
QUESTION IS WILL IT BE NORTH AND WEST OF THE CWA BORDER. HAVE
ADJUSTED POPS UPWARD IN THE FAR NORTH AND NORTHWEST CWA TO CHANCE
AND SOME LIKELIES IN THE FAR NW AROUND MID-DAY. SHOULD THIS ACTIVITY
AFFECT THE CWA...THERE COULD BE A PERIOD OF HEAVIER RAIN THANKS TO
INCREASING PWATS AND ALSO ISOLATED LIGHTNING STRIKES.
LATER IN THE AFTERNOON THROUGH THE EVENING...IT APPEARS THE BEST
FOCUS FOR ADDITIONAL TSRA WOULD BE CLOSER TO THE WARM FRONT IN
SOUTHERN WI...BUT THERE IS CONCERN THAT OUTFLOW FROM MORNING/MID-DAY
ACTIVITY COULD SERVE AS FOCUS FOR AFTERNOON STORMS IF CAPPING IS
WEAK ENOUGH. TRAJECTORY ANALYSIS SHOWS OUR AIR MASS TOMORROW COMING
FROM CENTRAL ARKANSAS WHERE TEMPS ARE IN MID AND UPPER 70S AND
DEWPOINTS PRIMARILY IN LOW-MID 50S. THINK THAT 60 DEG DEWPOINTS
SURGING IN ON SOME GUIDANCE SUCH AS NAM ARE TOO HIGH AND AFTERNOON
TSRA ACTIVITY WILL BE LESS WIDESPREAD THAN SHOWN BY 12Z NAM. THE
OTHER CON IS THAT UPPER SUPPORT DURING THE DAY DOESNT APPEAR ALL
THAT ROBUST OVER THE HEART OF THE CWA. HAVE NONETHELESS BROUGHT
CHANCE POPS DOWN TO A LINE ROUGHLY FROM THE NORTH SIDE OF CHICAGO TO
VYS AND LIKELIES IN FAR NW. SPC HAS INCLUDED AREA FROM CHICAGO TO LA
SALLE COUNTY IN DAY 2 SLIGHT RISK AND LOW AND DEEP LAYER SHEAR WILL
POTENTIALLY BE SUPPORTIVE OF ALL SEVERE MODES WITH ANY STORMS THAT
FORM INTO THE EVENING IN THE PRESENCE OF 500-1000 J/KG OF MLCAPE.
HAVE LEFT GOING HIGH TEMPERATURE FORECAST OF MID TO UPPER 70S
LARGELY UNCHANGED...THOUGH THERE ARE QUESTIONS IN IMPACTS FROM
CONVECTION AND CLOUD COVER...AS WELL AS A SOUTHEAST COMPONENT FOR
PART OF DAY INTO FAR NORTHEAST ILLINOIS. AS MENTIONED ABOVE...THE
OTHER CONCERN TOMORROW IS WITH STRONG SOUTHERLY WINDS GUSTING UP TO
35 MPH...ESPECIALLY SOUTH OF I-80.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...
HAVE CONTINUED TO FOCUS HIGHEST/CAT POPS INTO NORTHWEST AND
NORTHERN CWA WHERE MULTIPLE WAVES WILL BE RIDING IN ON SOUTHWEST
FLOW ALOFT AND THERE WILL BE BETTER MOISTURE CONVERGENCE NEAR THE
STALLED FRONTAL BOUNDARY. MOST LIKELY TIME FOR SURFACE BASED
CONVECTION WOULD BE DURING EVENING HOURS BEFORE BOUNDARY LAYER
SLOWLY STABILIZES. THERE WILL BE INSTABILITY ALOFT PRESENT THROUGH
THE NIGHT TO SUPPORT CONTINUED THUNDER MENTION HOWEVER. IT WILL BE A
MILD NIGHT WITH LOWS IN THE UPPER 50S TO AROUND 60.
DIFFERENCES STILL EXIST IN TIMING AND TRACK OF STRONGER LOW PRESSURE
MOVING NORTHEAST INTO THE AREA ON SUNDAY. ELEVATED WARM FRONT
BOUNDARY WILL REMAIN NORTH OF THE CWA...KEEPING STRONG MOISTURE
TRANSPORT FOCUSED INTO NORTH AND NORTHWEST CWA ESPECIALLY. AFTER A
VERY DRY PAST MONTH IN OUR NORTH AND NORTHWEST...INGREDIENTS COMING
TOGETHER FOR A SIGNIFICANT RAINFALL EVENT...WITH SOME AREAS
POSSIBLY SEEING IN EXCESS OF 3 INCHES OF RAIN. THIS COULD RESULT IN
LOW LYING FLOODING AND ALSO SIGNIFICANT RISES ON AREA RIVERS. WILL
HIGHLIGHT POTENTIAL WITH AN ESF THAT WILL BE ISSUED SHORTLY. A LARGE
TEMPERATURE GRADIENT WILL DEVELOP OVER THE CWA SUNDAY
AFTERNOON...WITH 70S SOUTH AND QUITE POSSIBLY 40S NORTH OF THE FRONT
OVER NORTHEAST IL. CONCERNED FOR SOUTHERLY GUSTS UP TO 40 MPH SOUTH
OF THE FRONT AND ALSO WITH DEWPOINTS NEARING 60...STRONG TO SEVERE
SURFACE BASED CONVECTION IN WARM SECTOR.
HEAVY RAIN WITH EMBEDDED TSRA LIKELY TO CONTINUE THROUGH SUNDAY
NIGHT. IT APPEARS THAT COLD ENOUGH AIR ALOFT MAY ARRIVE AFTER
MIDNIGHT AND COULD SUPPORT A MIX WITH SN IN THE NW CWA TOWARD
DAYBREAK MONDAY.
MONDAY...IT WILL BE A COLD AND BLUSTERY DAY AND QUITE THE RUDE
AWAKENING WITH HIGHS FOR MOST OF THE AREA IN THE LOW AND MID 40S!
THE QUESTION IS HOW QUICK IS THE DEEP LOW TO DEPART THE AREA...WITH
ECMWF CONTINUING TO BE SLOWEST AND FAVORING CHANCE TO LOW END LIKELY
POPS. MONDAY MORNING THERMAL PROFILES COULD SUPPORT WET SNOW MIXING
IN FOR NORTHERN PARTS OF THE AREA...THOUGH SURFACE TEMPS WILL BE
MARGINAL AT BEST. DIMINISHING WINDS AND CLEARING SKIES LATER MONDAY
NIGHT COULD SET THE STAGE FOR SUB FREEZING TEMPERATURES AREA WIDE.
LONG TERM...TUESDAY AND BEYOND...
TUESDAY WILL BE ANOTHER COLD DAY WITH WINDS LIKELY TURNING ONSHORE
IN THE AFTERNOON AND HIGHS AGAIN ONLY LOW-MID 40S. AFTER A
WIDESPREAD FREEZE POSSIBLE AGAIN TUESDAY NIGHT...THERE WILL BE A
GRADUAL WARMING TREND THE REST OF NEXT WORK WEEK. GUIDANCE DIFFERS
ON WHETHER A SYSTEM WILL APPROACH THE AREA LATE NEXT WEEK. STAYED
VERY CLOSE TO BLENDED INITIALIZATION GIVEN ACTIVE WEATHER THIS
WEEKEND.
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* SOUTH WINDS INCREASING ABOVE 10 KT THIS MORNING TO 15-20 KT BY
LATE MORNING WITH GUSTS 25KT+ DURING THE AFTERNOON. WINDS THEN
EASING OFF AROUND SUNSET.
* CHANCE OF THUNDERSTORMS SATURDAY EVENING.
ED F
//DISCUSSION...UPDATED 06Z...
A WEAK COLD FRONT LYING WEST TO EAST ACROSS NORTHERN IL AT 06 UTC WILL
REMAIN NEARLY STATIONARY THE REST OF THE NIGHT BEFORE LIFTING BACK
NORTH AS A WARM FRONT AFTER DAYBREAK SATURDAY. AS LOW PRESSURE
OVER SOUTH DAKOTA MOVES INTO IOWA LATER IN THE DAY... WINDS WILL
INCREASE OUT OF THE SOUTH WITH GUSTS FROM LATE MORNING THROUGH
EARLY EVENING. WARM MOIST AIR WILL SURGE NORTHWARD INTO THE AREA
LATER TODAY VIA THESE BRISK SOUTH WINDS AND HELP FUEL SHOWER AND
THUNDERSTORMS ALONG AND NORTH OF THE WARM FRONT ASSOCIATED WITH
THE AFOREMENTIONED LOW PRESSURE SYSTEM.
CHALLENGING FORECAST AS TO JUST HOW FAR SOUTH SOME OF THIS
CONVECTION MAY BRUSH... HOWEVER AT THIS POINT FEEL ANY RAIN AND
THUNDERSTORMS WILL REMAIN NORTH AND WEST OF THE ORD/MDW TERMINALS
THROUGH THE DAYTIME HOURS UNTIL 00-01 UTC SUNDAY.
ED F
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN STRONG SOUTH WINDS DEVELOPING BY LATE
MORNING SATURDAY... GUSTING DURING THE AFTERNOON.
* LOW CONFIDENCE IN CHANCE OF AND TIMING OF THUNDERSTORMS SATURDAY
EVENING AND OVERNIGHT.
ED F
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY...PERIODS OF SHRA/TSRA. IFR POSSIBLE...ESPECIALLY LATE.
MONDAY...MVFR LIKELY...IFR POSSIBLE. CHANCE OF RAIN.
TUESDAY THROUGH THURSDAY...VFR PROBABLE.
IZZI
&&
.MARINE...
221 PM CDT
A VERY ACTIVE WEATHER PERIOD IS EXPECTED OVER THE LAKE THIS WEEKEND
INTO EARLY NEXT WEEK. A STORM SYSTEM...CURRENT TAKING SHAPE ACROSS
THE NORTHERN HIGH PLAINS...IS EXPECTED TO MOVE OUT ACROSS THE UPPER
MIDWEST ON SATURDAY...THEN MOVE ACROSS THE CENTRAL PORTION OF THE
LAKE SATURDAY NIGHT. THIS LOW LOOKS TO DRAPE A FRONTAL BOUNDARY
SOMEWHERE ACROSS THE CENTRAL AND SOUTHERN SECTIONS OF THE LAKE INTO
SUNDAY...JUST PRIOR TO ANOTHER AREA OF LOW PRESSURE TRANSITIONING
ACROSS NORTHEASTWARD ACROSS SOUTHERN LAKE MICHIGAN ALONG THIS
FRONTAL BOUNDARY SUNDAY NIGHT INTO MONDAY.
OVERALL...THIS WILL RESULT IN A RATHER COMPLEX WIND FORECAST ACROSS
THE LAKE OVER THE NEXT COUPLE OF DAYS...AS THERE WILL BE LIKELY BE
LARGE VARIATIONS IN SPEEDS AND DIRECTIONS ACROSS DIFFERENT SECTIONS
OF THE LAKE. AS IT APPEARS NOW...EASTERLY WINDS WILL BE FAVORED
ACROSS THE NORTHERN 1/3 OF THE LAKE THROUGH SATURDAY
EVENING...BEFORE SHIFTING OUT OF THE NORTH INTO SUNDAY. FARTHER
SOUTH...IT APPEARS AN EASTERLY WIND COMPONENT EARLY SUNDAY WILL
GRADUALLY SHIFT SOUTHEASTERLY...AND EVEN SOUTHERLY BY LATE
SATURDAY...ESPECIALLY ACROSS SOUTHERN LAKE MICHIGAN TO THE SOUTH OF
THE EVOLVING SURFACE BOUNDARY. WIND SPEEDS WILL LIKELY INCREASE
LATER SATURDAY WITH THE APPROACH OF THE FIRST LOW...THIS WILL LIKELY
RESULT IN SMALL CRAFT ADVISORY CONDITIONS FOR THE ILLINOIS AND INDIAN
NEAR SHORES...AS SOUTHERLY WINDS OF 25 TO 30 KT DEVELOP DURING
SATURDAY AFTERNOON AND EVENING.
BY SUNDAY...STRONG NORTHERLY WINDS ARE EXPECTED TO BEGIN DEVELOPING
FROM NORTH TO SOUTH DOWN THE LAKE AS THE SECOND AREA OF LOW PRESSURE
TRACKS ACROSS THE SOUTHERN PORTION OF THE LAKE. ALTHOUGH WINDS
ACROSS THE SOUTH PORTIONS OF THE LAKE MAY BECOME RELATIVELY LIGHT
FOR A PERIOD EARLY ON SUNDAY AS THE LOW APPROACHES...EXPECT
NORTHERLY WINDS TO SET UP AND INCREASE BY SUNDAY NIGHT. IT STILL
APPEARS THE BEST THREAT FOR A PERIOD OF GALES TO 40 KT WILL BE
SUNDAY NIGHT INTO EARLY MONDAY AS COLDER AIR MOVES IN OVER THE LAKE
IN THE WAKE OF THIS AREA OF LOW PRESSURE.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...10 AM SATURDAY TO
4 AM SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...10 AM SATURDAY TO
10 PM SATURDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
1152 PM CDT Fri Apr 11 2014
.DISCUSSION...
ISSUED 844 PM CDT Fri Apr 11 2014
Made some minor tweaks to the forecast and grids, mainly related
to temperature. The latest surface analysis indicated a weak
surface ridge extending from southern IN back across central IL to
northern MO. Dew points were still very low with upper 20s to 30s
in central IL and lower 40s in the southeast. These will be
nudging up a bit as the night progresses, particularly in
southeast IL.
Most of the upstream cloud cover is scattered to broken high
clouds with a few mid clouds, so the insulating effects will be
minimal. Thus, nudged overnight lows down a bit in central IL with
the all of the dry air and very light wind anticipated.
Windy conditions are in store for the region Saturday, starting
from mid-morning and continuing into early evening. Sustained wind
of 20 to 25 mph with gusts of 35 to 40 mph from the south will be
common during the day tomorrow.
&&
.AVIATION...
ISSUED 1151 PM CDT Fri Apr 11 2014
VFR conditions will prevail at the central and eastern IL TAF
sites for the next 24 hours. It appears that the low level
moisture pushing slowly northward through extreme southern IL is
not expected to be associated with MVFR ceilings. Forecast
soundings and cloud base height forecasts from the HRRR indicate
that the VFR ceilings are expected when the low level moisture
lifts into central IL around and shortly after daybreak.
Still expecting very windy conditions from about mid-morning
into early evening as the pressure gradient increases and plenty
of mixing occurs in the lower atmosphere. BUFKIT momentum transfer
is still indicating the potential for wind gusts to reach 30-35
knots Saturday afternoon.
With the main surface boundary expected to stay along NW and
extreme northern IL, the precipitation will stay to the north of
the TAF sites in central IL through 06Z Sunday. The 00Z model runs
of the NAM and GFS indicate that the rain may even hold off until
later Sunday afternoon.
Miller
&&
.PREV DISCUSSION...
ISSUED 200 PM CDT Fri Apr 11 2014
SHORT TERM...Tonight through Monday
Slow moving storm system to bring "warm" air north into our area
for the next couple of days followed by the threat for heavy
rainfall over parts of central Illinois, especially late Sunday
afternoon through early Monday.
The main forecast concerns this period will be with temperatures
and timing of precip east into our area starting Saturday evening
far northwest and over the remainder of the area by Sunday night.
Models in decent agreement with respect to frontal position this
weekend but are having their usual problems with moisture advection
north into the Midwest. Both the NAM-WRF and operational GFS were
bringing in low 60 degree dew points north into our area tomorrow
afternoon and evening ahead of a slow moving frontal boundary
approaching from the northwest. Looking at upstream surface obs over
parts of Arkansas and southern Missouri, it appears the dew points
were forecast about 5 to 7 degrees too high for early this afternoon
compared to reality. So once again, will side more with the ARW
solution as it seems to mix out the lower levels of the atmosphere
more efficiently with afternoon dew points forecast mostly in the
mid 50s. In addition, forecast soundings suggest a much better
cumulus field across our area with the returning moisture as well
but that won`t hold temps back as 850 temps suggest afternoon
readings in the 75 to 80 degree range accompanied by south winds
gusting as high as 35 mph at times in the afternoon.
Aforementioned front will be settling southeast into central
Wisconsin southwest through west central Iowa by evening. Surface
base capes off the ARW soundings ranging from 1200-1500 j/kg
across far west central Illinois by late afternoon. With the main
forcing mechanism still well west and northwest of our area, feel
the better chances for scattered thunderstorms will be over eastern
Iowa northeast through northwest Illinois Saturday afternoon and
early evening. What those storms do with respect to an associated
outflow boundary and eventual propagation is still uncertain for
our northwest counties but it still warrants low chance POPs over
our far northwest areas by late afternoon with the better chances
spreading ever so slowly east and southeast during the late evening
hours of Saturday. Radar simulations off the SPC and HRW-WRF NMM
delay any significant convection until the 01z-04z time frame well
to our northwest as soundings suggest the cap will be slow to
break late in the afternoon. Even the NAM-WRF solution indicating
the better K indices remaining well to our northwest until late
Saturday night, and even that is confined to our far northwest
counties as the better 925-850 mb jet and favorable theta-e advection
during the evening remains well to our west. With the slower model
trends will keep the better chances for rain confined to our
northwest Saturday night into Sunday with the widespread rains
associated with the stronger upper wave and surface front will be
late Sunday afternoon into Monday morning.
Latest ECMWF has continued to trend slower with the overall speed
of the large 500 mb inching its way across the central U.S. into
early next week, with a secondary piece of energy near the base
of the trof seen on the latest run, which the 12z NAM-WRF was
hinting at as well. This has resulted in a much slower ending of
precip and actually shows a second wave of precip pushing northeast
ahead of the southern stream shortwave into an air mass supportive
of at least a rain snow mix by the end of the day Monday into
Monday night. Not going to jump on that bandwagon quite yet but it
will need to be watched.
LONG TERM...Tuesday through Friday
500 mb trof axis to shift to our east Tuesday afternoon with the
upper flow quickly transitioning back to zonal by mid-week which
should make for a quick recovery in temperatures. After some very
chilly readings Tuesday and Wednesday mornings with frost/freezing
temperatures possible, we should see readings return close to normal
by Thursday and Friday when afternoon temperatures climb back into
the 60s. If the ECMWF solution is correct, we may need to bump up
POPs Monday night across the east with most of the precip just off
to our east Tuesday morning. After that, not very confident on our
next chance for precip with the model blend plastering precip all
over the place later in the week. Next significant wave moving well
to our north late in the week, but with all the deeper moisture
shunted away with our early week trof, not much support for any
meaningful rain chances in the extended.
Smith
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
847 PM EDT SUN APR 13 2014
.SYNOPSIS...
ISSUED AT 830 PM EDT SUN APR 13 2014
SHOWERS AND SCATTERED THUNDERSTORMS WILL BECOME MORE PREVALENT
TONIGHT AS AN UPPER LEVEL DISTURBANCE APPROACHES THE REGION FROM
THE PLAINS. A COLD FRONT ASSOCIATED WITH THIS SYSTEM WILL TRACK
ACROSS THE REGION ON MONDAY...BRINGING COLDER AND BLUSTERY
CONDITIONS. RAIN WILL TAPER IN COVERAGE DURING THE DAY
MONDAY...BUT ANOTHER DISTURBANCE WILL BRING A CHANCE OF LIGHT SNOW
ACCUMULATIONS FOR MONDAY NIGHT.
&&
.UPDATE...
ISSUED AT 830 PM EDT SUN APR 13 2014
AN AREA OF SHOWERS AND ISOLATED THUNDERSTORMS ASSOCIATED WITH
SMALL SCALE UPPER VORT MAX SHOULD EXIT FAR NORTHWEST PORTIONS OF
THE AREA OVER THE NEXT OVER. LULL IN PRECIP WILL BE RELATIVELY
SHORT LIVED AS STRONGER UPPER LEVEL SHORT WAVE WILL CONTINUE TO TRACK
INTO NORTHWEST INDIANA OVERNIGHT. A LARGE AREA OF ENHANCED LOW
LEVEL MOISTURE TRANSPORT NOTED PER LATEST RAP ANALYSIS ACROSS THE
MID MS RIVER VALLEY WILL SHIFT EASTWARD AND EXTEND FROM THE LOWER
OHIO VALLEY INTO THE SOUTHERN GREAT LAKES BY 09Z. A LARGE AREA OF
RAIN/EMBEDDED THUNDERSTORMS COINCIDING WITH THIS STRONGER LOW
LEVEL MOISTURE TRANSPORT ACROSS SOUTHEAST MISSOURI WILL CONTINUE
TO EXPAND NORTHEASTWARD OVERNIGHT...BRINGING WIDESPREAD
RAIN/EMBEDDED THUNDER TO MOST OF THE FORECAST AREA THROUGH EARLY
MONDAY MORNING. NORTHWARD ADVECTION OF 1.25-1.40 INCH PWAT AXIS
INTO THE AREA OVERNIGHT AND STRENGTHENING LOW LEVEL FRONTAL
CIRCULATION SHOULD PROMOTE SOME HEALTHY RAINFALL AMOUNTS POSSIBLY
APPROACHING AROUND AN INCH ACROSS WESTERN PORTIONS OF THE AREA
WHICH COULD LEAD TO SOME MINOR FLOODING CONCERNS GIVEN RECENT WET
PERIOD/MOIST SOILS. MAIN TWEAKS TO FORECAST THIS EVENING WERE TO
SLIGHTLY INCREASE POPS OVERNIGHT IN ASSOCIATION WITH ABOVE
MENTIONED TRENDS...ALONG WITH SLIGHT ADJUSTMENT TO HOURLY TEMP
CURVE ACROSS THE NORTHWEST COOLER TEMPS RESIDE INITIALLY DUE TO
EARLIER MARINE INFLUENCE. BEST CHANCE OF THUNDER APPEARS TO BE
DURING THE OVERNIGHT HOURS...WHERE SLIGHT ENHANCEMENT TO WEAK
ELEVATED INSTABILITY IS EXPECTED IN ASSOCIATION WITH LOW LEVEL
MOIST TONGUE.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 328 PM EDT SUN APR 13 2014
VIGOROUS LOW PRESSURE OVR KS THIS AFTN WILL LIFT QUICKLY NEWD INTO
THE MI THUMB BY DAYBREAK TOMORROW AND PROPEL A STG CDFNT EWD ACRS
THE AREA. SO FAR WARM SECTOR HAS BEEN A DUD WITH THIS SYS OWING TO
POOR MSTR RTN UNDERNEATH STEEP EML AND SEE LTL EVIDENCE THAT WILL
CHANGE INTO EARLY EVE.
BETTER PROSPECTS FOR RAINFALL XPCD LT TONIGHT AHD AND ALG SFC FNTL
BNDRY. HWVR WKNG CAP WITHIN ZONE OF FVRBL THETA-E AND SUSTAINED LL
WAA STILL WARRANTS HOLDING ONTO SOME POPS NW THIRD THROUGH EVENING.
OTRWS STG POST FNTL CAA WEDGE FOLLOWS MON AM W/CRASHING SFC TEMPS.
LINGERING POST FNTL SHRA XPCD IN THE MORNING FOLLOWED BY LARGELY DRY
CONDS IN THE AFTN ASSOCD/W MID LVL DRY SLOT OF EXITING SYS ALOFT.
&&
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 328 PM EDT SUN APR 13 2014
FOCUS OF FORECAST WILL BE ON ARRIVAL OF UNSEASONABLY COLD AIR AND
ACCUMULATING SNOWFALL AT THE START OF THE PERIOD.
COLD FRONT SHOULD BE LONG GONE BY MONDAY EVENING WITH THE REGION IN
A VERY BRIEF LULL IN PRECIP TO START THINGS OUT. THIS WILL QUICKLY
CHANGE AS A DISTURBANCE MOVES ALONG THE FRONT AND BRINGS ANOTHER
QUICK SHOT OF INCREASED MSTR AND LIFT. MODELS DO VARY ON EXACTLY HOW
MUCH QPF BUT IN GENERAL PAINT THE NEED FOR LIKELY TO CAT POPS FOR
MOST AREAS FOR A PERIOD...MAINLY IN THE 3Z TO 9Z TUES TIME FRAME.
HAVE BROKE GRIDS INTO 3 HOUR BLOCKS TO TRY TO ADD SOME DETAIL IN
TERMS OF TIMING. GIVEN RATHER PRONOUNCED/FAST ARRIVING PUNCH OF COLD
AIR...MIX POTENTIAL FOR PRECIP LOOKING MORE LIMITED WITH 1000-850 MB
THICKNESS AND SFC TEMPS ALL POINTING TOWARDS ALL SNOW. THE BIGGEST
CHALLENGE LIE WITH HOW MUCH PRECIP FALLS AND POTENTIAL
ACCUMULATIONS. IMPRESSIVE 850 MB DROP FOR MID APRIL WITH VALUES FROM
-8 TO - 10 C DURING BEST PRECIP WINDOW. AT THIS TIME...THINK MANY
AREAS WILL SEE SOME WET SNOWFLAKES TO START THINGS OFF IN THE
EVENING...WITH THIS SNOW BEING LESS WET WITH TIME AS COLDER AIR
SETTLES IN AND SNOW RATIOS INCREASE SOMEWHAT. IF WE WERE STILL
ENTRENCHED IN THE GENERALLY COLD PATTERN...WE MIGHT BE LOOKING AT
SEVERAL INCHES OF SNOW STICKING AROUND AND CAUSING A LOT OF
PROBLEMS. HOWEVER...DESPITE THE COLD AIR ARRIVING...ROAD/GROUND
TEMPS HAVE WARMED SUBSTANTIALLY GIVEN THE 70S OF THE PAST COUPLE OF
DAYS. THIS WILL LIKELY ALLOW FOR MELTING OF A LOT OF THE
SNOWFALL...ESPECIALLY ON ROADS. HOWEVER...IF SNOW CAN COME DOWN HARD
ENOUGH IT MAY BE ABLE TO ACCUMULATE AND STICK AROUND BRIEFLY INTO
PARTS OF TUESDAY AS HIGHS STRUGGLE THROUGH THE 30S TO NEAR 40. GRIDS
REFLECT ACCUMULATIONS OF 1 TO 3 INCHES WITH HIGHEST AMOUNTS IN SE
AREAS WHERE MSTR WILL LINGER LONGER. AGAIN...IT NEEDS TO BE STRESSED
THAT MUCH OF THIS SNOW MAY NOT ACCUMULATE IN THE EVENING BUT
OVERNIGHT...ROADS COULD BECOME SLIPPERY IN SOME AREAS AS OVERNIGHT
LOWS PLUMMET THROUGH THE 20S. FORECAST WILL NEED FINE TUNING FURTHER
OVER THE NEXT 12 TO 24 HOURS.
ONCE THIS SYSTEM PASSES BY...DRIER WEATHER WILL SETTLE IN UNTIL
THURS NGT BEFORE THE NEXT SYSTEM BEGINS TO APPROACH THE REGION WITH
CHANCES FOR SHOWERS. TEMPS WILL CLIMB BACK INTO THE 50S AND POSSIBLY
60S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 830 PM EDT SUN APR 13 2014
LEAD SHORT WAVE WILL CONTINUE TO BRING A PERIOD OF RAIN SHOWERS
AND PERHAPS AN ISOLATED THUNDERSTORM TO KSBN OVER THE NEXT HOUR. A
BRIEF LULL IN RAIN SHOWER COVERAGE IF POSSIBLE AFTER 01Z...BUT
RAIN WILL BECOME MORE WIDESPREAD OVERNIGHT WITH SOME EMBEDDED
THUNDER AS A SHORT WAVE TROUGH LIFTS NORTHEAST INTO THE AREA. AN
AXIS OF ENHANCED MOISTURE WILL ALSO ADVECT INTO NORTHERN INDIANA
OVERNIGHT AHEAD OF THE UPPER TROUGH/COLD FRONT WHICH SHOULD ALSO
ALLOW FOR A PERIOD OF MODERATE TO HEAVY RAIN...MAINLY IN THE 06Z-
12Z TIMEFRAME. WITH INSTABILITY QUITE LIMITED IN MAGNITUDE HAVE
RESTRICTED THUNDER MENTION TO VCTS AT THIS TIME. SOUTH WINDS
GUSTS ARE EXPECTED TO INCREASE OVERNIGHT AS SFC PRESSURE FALLS
OVERSPREAD SOUTHERN GREAT LAKES...WITH GUSTY NORTHWEST WINDS TO 30
KNOTS ON MONDAY BEHIND THE FRONT. IFR CONDITIONS ARE ALSO EXPECTED
WITH THE PERIODS OF HEAVIER RAIN LATE TONIGHT INTO EARLY
MONDAY...EVENTUALLY IMPROVING TO MVFR BEHIND THE FRONT TOWARD
MIDDAY MONDAY.
&&
.MARINE...
ISSUED AT 328 PM EDT SUN APR 13 2014
AREAS OF FOG BEING INTRODUCED TO NEARSHORE WATERS WITH WEB CAMS
SHOWING FOG OFFSHORE...MORE THAN LIKELY MORE IN THE 3 TO 5 NM
RANGE. TRENDS WILL BE MONITORED FOR NEED FOR MARINE DENSE FOG
ADVISORY BUT MAIN THREAT SHOULD REMAIN IN OPEN WATERS.
WILL ALSO HOIST SMALL CRAFT ADVISORY STARTING LATER TONIGHT AND
CONTINUING THROUGH AT LEAST MONDAY IF NOT INTO TUESDAY. POTENTIAL
FOR A PERIOD OF GALE FORCE GUSTS BUT HAVE KEPT WORDING TONED DOWN
FOR THE TIME BEING WITH A FEW GUSTS TO 35 KTS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY FROM 2 AM TO 8 PM EDT MONDAY FOR LMZ043-046.
&&
$$
UPDATE...MARSILI
SYNOPSIS...MARSILI
SHORT TERM...T
LONG TERM...FISHER
AVIATION...MARSILI
MARINE...FISHER
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
444 PM CDT SAT APR 12 2014
.UPDATE...
ISSUED AT 437 PM CDT SAT APR 12 2014
BASED ON CLOUD/RADAR TRENDS AND WHAT IS BEING SUGGESTED INTERNALLY
BY TRENDS FROM THE RAP ETC...A MAJORITY OF THE CURRENT CONVECTION
SHOULD MOVE ALONG JUST NORTH OF THE AREA THROUGH 7 PM. ADDITIONAL
CONVECTION SHOULD DEVELOP TO THE WEST OR WEST/SOUTHWEST ALONG THE
BOUNDARY TOWARD KEBS.
THERE ARE SUGGESTIONS OF NEW CONVECTIVE BOUNDARIES HELPING TO
DEVELOP/PUSH CONVECTION VERY SLOWLY INTO THE HIGHWAY 20 CORRIDOR
WEST OF KDBQ BETWEEN 5 AND 7 PM.
AFTER 7 PM...IT WILL ONLY BE A MATTER OF TIME BEFORE CONVECTIVE
BOUNDARIES AND THE MAIN SYNOPTIC BOUNDARY DEVELOP SCATTERED
CONVECTION THAT BECOMES MORE NUMEROUS AS THE EVENING PROGRESSES.
&&
.SYNOPSIS...
ISSUED AT 302 PM CDT SAT APR 12 2014
A VERY PRONOUNCED FRONTAL BOUNDARY IS LOCATED FROM SIOUX CITY
IOWA THROUGH FAR SOUTHWEST WISCONSIN AS OF 2 PM. THIS FRONT HAS
BEEN THE FOCUS FOR ON ROUND OF SEVERE STORMS...AND WILL BE AGAIN
THE FOCUS IN A FEW HOURS. THE MORNING ROUND OF SEVERE ELEVATED
STORMS PRODUCED COPIOUS AMOUNTS OF LARGE HAIL...AS WELL AS A VERY
STRONG PROGRESSIVE DOWN BURST WITH ONE SUPERCELL ALONG HIGHWAY 20
IN STEPHENSON COUNTY. THIS DOWN BURST MAY HAVE PRODUCED WINDS IN
EXCESS OF 75 MPH.
THE WARM SIDE OF THE BOUNDARY WHICH IS OVER THE ENTIRE CWA...IS WELL
MIXED AND CONTINUES TO WARM. TEMPERATURES ARE NEAR 80 OVER ALL OF
THE CWA...MAKING THIS EASILY THE WARMEST DAY IN MANY MONTHS.
DEWPOINTS IN THE MID TO UPPER 50S ARE ALREADY ESTABLISHED OVER THE
MIDWEST...AND ANY FURTHER INCREASE WILL LIKELY OCCUR THROUGH
CONVERGENCE PROCESSES.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 302 PM CDT SAT APR 12 2014
TONIGHT WILL SEE STORMS FIRE INITIALLY IN NORTH CENTRAL IOWA TO
NORTHEAST IOWA. DEEP LAYER SHEAR IS SUFFICIENT FOR
SUPERCELLS...MUCH LIKE EARLIER TODAY. THIS PORTION OF THE EVENT
SHOULD BE JUST NORTH OF THE CWA...BUT COULD IMPACT OUR FAR NORTHWEST
THROUGH 7 PM. EITHER WAY...IT IS GOING TO BE CLOSE. BY LATER IN THE
EVENING...A COLD POOL SHOULD BE WELL ESTABLISHED ALONG THE
FRONT...ALLOWING STORMS TO PUSH EAST AND SOUTH AS A LINE OR BROKEN
LINE. AT THAT TIME...THE THREAT SHOULD TRANSITION TO WIND...BEFORE
THE LINE STALLS OR RUNS INTO A MORE STOUT CAP/EML STILL PRESENT IN
THE WARM SECTOR. WHERE EVER THIS OCCURS...THE LINE SHOULD STALL OR
AT LEAST SLOW FOR A POTENTIAL FOR REPEATING/TRAINING STORMS.
THUS...THE HIGHEST PROBABILITY FOR SEVERE IS NORTHWEST...AS IS
POPS...BUT IT LOOKS LIKE THE HIGHER PROBABILITY FOR TRAINING IS
JUXTAPOSED TO THE SOUTHEAST...OVER OUR CENTRAL CWA FROM SOUTHWEST TO
NORTHEAST. AS MESOSCALE PROCESSES EVOLVE...WE CAN GREATLY REFINE
THIS DUAL THREAT. RAINS TONIGHT WILL BE SIGNIFICANT WITH OVER 1
INCH WHERE STORMS LAY OUT VERY LIKELY.
SUNDAY...THE MAIN MOISTURE AND SYSTEM DYNAMICS ARRIVE IN THE
MORNING...FOR ANOTHER CONVECTIVE ROUND OF THUNDERSTORMS. MUCH
STRONGER UPPER DIFLUENCE IS FORECAST...BUT LESSER CAPE.
THUS...EFFICIENT RAINFALL PROCESSES WITH HIGH PWAT VALUES SHOULD
SUPPORT RAIN RATES OVER 0.5 PER HOUR AT TIMES. WITH STRONG FORCING
ALL DAY...WE COULD SEE RAINFALL OF 1 TO 2 INCHES SUNDAY OVER THE
WESTERN 2/3 OF THE CWA. IF WE WERE NOT IN DROUGHT...WITH UNFROZEN
GROUND...THIS WOULD BE AN EASY FLASH FLOOD RISK...BUT THAT IS NOT
THE CASE. WHILE WE MAY SEE SOME THREAT FOR FLASH FLOODING...AND
RIVER FLOODING...IT DOES NOT LOOK WIDESPREAD ENOUGH TO WARRANT A
WATCH GIVEN THE DRY ANTECEDENT CONDITIONS. ERVIN
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 302 PM CDT SAT APR 12 2014
THE MAIN FORCING ARRIVES SUNDAY EVENING SO WIDESPREAD RAIN WITH SOME
EMBEDDED THUNDERSTORMS SHOULD BE SEEN. AFTER MIDNIGHT THE OVERALL
FORCING BEGINS TO WEAKEN AS COLDER AIR STARTS GETTING PULLED INTO
THE AREA.
THE QUESTION AFTER MIDNIGHT IS HOW FAST DOES THE COLD AIR ARRIVE.
BASED ON WHAT IS BEING SUGGESTED A MIX SHOULD DEVELOP PRIOR TO
SUNRISE MONDAY OVER THE FAR NORTHWEST PARTS OF THE AREA.
FOR THE FIRST FEW HOURS AFTER SUNRISE MONDAY THE MIX OF RAIN AND
SNOW WILL MOVE SOUTHEAST WITH THE EXTREME NORTHWEST CHANGING OVER TO
ALL SNOW. DUE TO THE WARMER GROUND ANY ACCUMULATIONS SHOULD BE A
DUSTING AT BEST.
AS MONDAY MORNING PROGRESSES...SOLAR INSOLATION WILL SLOWLY PUSH
TEMPERATURES UP IN SPITE OF THE CLOUDS AND PRECIPITATION. BY LATE
MORNING THE PRECIPITATION SHOULD CHANGE BACK TO ALL RAIN WITH RAIN
ENDING FROM WEST TO EAST MONDAY AFTERNOON. TEMPERATURES WILL AVERAGE
WELL BELOW NORMAL.
LINGERING LIGHT RAIN WILL BE SEEN ACROSS THE FAR EAST EARLY MONDAY
EVENING BEFORE ENDING. THE REMAINDER OF MONDAY NIGHT WILL BE DRY AND
COLD AS CANADIAN HIGH PRESSURE BUILDS INTO THE MIDWEST.
QUIET AND COOL CONDITIONS WILL BE SEEN ACROSS THE AREA ON TUESDAY AS
THE HIGH REMAINS ACROSS THE MIDWEST. TEMPERATURES WILL CONTINUE TO
AVERAGE WELL BELOW NORMAL.
TUESDAY NIGHT ON...
THE CURRENT MODEL CONSENSUS HAS DRY CONDITIONS TUESDAY NIGHT THROUGH
WEDNESDAY NIGHT WITH TEMPERATURES AVERAGING SLIGHTLY BELOW NORMAL.
THURSDAY THROUGH SATURDAY THE MODEL CONSENSUS GOES FROM SLIGHT
CHANCE POPS THURSDAY...TO CHANCE POPS THURSDAY NIGHT THROUGH
SATURDAY.
THERE IS LOOSE AGREEMENT THAT ANOTHER SLOW MOVING STORM SYSTEM WILL
AFFECT THE MIDWEST IN THE THURSDAY THROUGH SATURDAY TIME FRAME.
HOWEVER...THERE ARE DIFFERENCES BETWEEN THE MODELS AS TO HOW THE
STORM SYSTEM WILL EVOLVE AND WHERE IT TRACKS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1216 PM CDT SAT APR 12 2014
WHILE CONDITIONS WILL BEGIN WITH WIDESPREAD VFR TODAY...THEY WILL
END WITH WIDESPREAD SHOWERS AND THUNDERSTORMS WITH IFR CONDITIONS.
A LARGE COMPLEX OF STORMS WILL DEVELOP IN CENTRAL IOWA AND MOVE
EAST TO NORTHEAST...AFFECTING CID AND DBQ BY MID EVENING...AND
POSSIBLY MLI AND BRL LATE EVENING. OVERNIGHT...SCATTERED SHOWERS
AND STORMS ARE POSSIBLE WITH MVFR/IFR CIGS AND VISIBILITIES IN ALL
LOCATIONS. SUNDAY SHOWS NO IMPROVEMENT AS A LOW PRESSURE MOVES INTO
ILLINOIS. THIS WILL SWITCH WINDS FROM SOUTH TO NORTHEAST...AND
BRING STEADY IFR CIGS TO MOST OF THE AREA WITH WIDESPREAD
MODERATE RAIN. THUNDER WILL ALSO BE POSSIBLE THROUGHOUT THE DAY
SUNDAY BUT IS EXPECTED TO BE LESS INTENSE DUE TO THE WIDESPREAD
NATURE OF THE RAINS.
ERVIN
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...ERVIN
SHORT TERM...ERVIN
LONG TERM...08
AVIATION...ERVIN
AREA FORECAST DISCUSSION
NWS GOODLAND KS
903 PM MDT SUN APR 13 2014
.UPDATE...
ISSUED AT 901 PM MDT SUN APR 13 2014
NEWER MODEL DATA IS CONFIRMING WHAT RECENT OBSERVATION AND RADAR
TRENDS HAVE SHOWING WITH THE DECREASING TREND OF THE SNOW. HAVE
CANCELLED THE WINTER WEATHER ADVISORY FOR RED WILLOW...DECATUR AND
NORTON COUNTIES.
UPDATE ISSUED AT 803 PM MDT SUN APR 13 2014
HAVE RECENTLY COMPLETED A COUPLE OF UPDATES. HAVE ALLOWED THE WIND
ADVISORY TO EXPIRE WITH WINDS BELOW CRITERIA. REST OF FORECAST
LOOKING ON TRACK. HAVE ADJUSTED WEATHER AND POPS TO REFLECT THE
TRENDS SEEN ON OBSERVATIONS...SATELLITE AND RADAR. WINTER WEATHER
ADVISORY DOING FINE WITH EXPECTED LIFT TO CONTINUE THROUGH MIDNIGHT.
EASTERN END OF THE ADVISORY MAY NOT GET TOO MUCH MORE SNOW BUT WILL
KEEP IT WITH THE EXPECTED INTENSITY OF SNOW COMBINED WITH WHAT HAS
ALREADY AND THE WINDY CONDITIONS.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 203 PM MDT SUN APR 13 2014
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW LARGE UPPER LEVEL
TROUGH ACROSS NORTHERN/CENTRAL US WITH TWO DISTINCT H5/H7
CIRCULATIONS OVER THE PLAINS AND CENTRAL ROCKIES. THE FIRST
CIRCULATION IS ASSOCIATED THE H5/H7 LOW NO OVER CENTRAL/EASTERN
NEBRASKA...RESPONSIBLE FOR DEFORMATION BAND OF SNOW THAT FORMED
OVER NORTHEAST COLORADO EARLY THIS MORNING AND IS NOW OVER THE
NORTHERN PART OF OUR CWA. THE SECOND CIRCULATION IS ASSOCIATE
WITH A SECOND CLOSED H7 LOW AND H5 TROUGH DEEPENING OVER WESTERN
COLORADO.
REGARDING WIND ADVISORY THIS AFTERNOON/EVENING...WINDS HAVE
STRUGGLED TO APPROACH CRITERIA THOUGH THEY HAVE BEEN NEAR ADVISORY
CRITERIA AT TIMES. THE PLAN IS TO HOLD ONTO THE ONGOING WIND
ADVISORY FOR A FEW MORE HOURS AS THE BEST PRESSURE RISES ARE
BEGINNING TO SHIFT TO THE SOUTH AND EAST...AND PROBABLY CANCEL THE
ADVISORY BEFORE 00Z.
REGARDING WINTER WEATHER ADVISORY...AS MENTIONED IN THE SYNOPSIS
THERE ARE TWO DISTINCT UPPER LEVEL CIRCULATIONS RESPONSIBLE FOR
BRINGING WINTRY WEATHER TO OUR CWA TODAY/TONIGHT. THE DEFORMATION
BAND ASSOCIATED WITH THE CIRCULATION OVER NEBRASKA SHOULD CONTINUE
TO TRANSITION NORTH AND EAST...WITH MAIN IMPACT OVER THE NORTHERN
PART OF THE CWA WINDING DOWN AROUND 00Z. I COULD SEE US CANCELING
THE NORTHERN PART OF THE ADVISORY EARLY (00Z-03Z) AS WE WILL LIKELY
NOT SEE ADVISORY CRITERIA MET UP NORTH WITH THE 2ND UPPER LOW. THE
SOUTHERN PART OF THE ADVISORY (KIT CARSON/CHEYENNE CO) HAVE
AVOIDED THE BRUNT OF THIS FIRST WAVE...HOWEVER THE SECOND
CIRCULATION WILL BEGIN TO BRING LIGHT TO MODERATE SNOW INTO
EASTERN COLORADO THIS EVENING AND THIS IS WHEN THESE LOCATIONS
MAY SEE THE GREATEST IMPACT. CONFIDENCE IS ACTUALLY HIGHER FOR KIT
CARSON/CHEYENNE CO TO MEET ADVISORY CRITERIA THIS EVENING THAN
SHERMAN. SHERMAN/WALLACE/GREELEY COULD BE CLOSE BASED ON LATEST
MODEL OUTPUT...HOWEVER CONFIDENCE IS TOO LOW TO ADD
WALLACE/GREELEY...OR CANCEL SHERMAN AT THIS POINT. WE WILL NEED TO
MONITOR NEAR TERM TRENDS. PRECIP SHOULD QUICKLY WIND DOWN THIS
EVENING IN THE NORTH AND THEN AFTER MIDNIGHT ACROSS THE
SOUTH...WITH MAYBE SNOW LINGERING THROUGH MID MORNING MONDAY IN
THE FAR SOUTH.
REGARDING ANTICIPATED IMPACTS THIS AFTERNOON/EVENING...ADDITIONAL
LIGHT SNOW ACCUMULATIONS ARE ANTICIPATED FOR MOST
LOCATIONS...HOWEVER MODERATE-HEAVY ACCUMULATIONS ARE MOST LIKELY
THIS EVENING OVER KIT CARSON/CHEYENNE COLORADO COUNTIES. WINDY
CONDITIONS WILL CONTINUE...AND WILL CONTINUE BRING BLOWING SNOW
CHANCES AND LOCALLY REDUCED VISIBILITIES THROUGH AROUND 03Z.
LATE TONIGHT/MONDAY TEMPS...HARD FREEZE IS LIKELY WITH SUB
FREEZING TEMPS ALREADY ACROSS MOST OF THE CWA...AND UPSTREAM TEMPS
IN THE 23-25F ALREADY BEING REPORTED. TOO EARLY IN THE SEASON TO
ISSUE FROST/FREEZE HIGHLIGHTS CONSIDERING CLIMATE NORMS FOR LAST
FROST/FREEZE. AIR MASS WILL BEGIN TO MODERATE SOME MONDAY...HOWEVER
HIGHS WILL REMAIN WELL BELOW NORMAL WITH VALUES IN THE 40S ACROSS
THE CWA.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 210 PM MDT SUN APR 13 2014
A SHORT WAVE RIDGE MOVES OVER THE ROCKIES AND FLATTENS AS IT MOVES
ACROSS THE HIGH PLAINS BETWEEN MONDAY NIGHT THROUGH TUESDAY
NIGHT. TEMPERATES WILL WARM AND CONDITIONS WILL DRY DURING THAT
TIME. BETWEEN LATE WEDNESDAY THROUGH THURSDAY NIGHT ANOTHER LOW
PRESSURE SYSTEM WILL MOVE THROUGH THE ROCKIES AND HIGH PLAINS
REGIONS...BRINGING ANOTHER ROUND OF COOLER TEMPERATURES AND A
CHANCE OF PRECIPITATION TO THE CENTRAL HIGH PLAINS. A MIXTURE OF
RAIN AND SNOW IS EXPECTED WITH THIS SYSTEM.
MODEL SOLUTIONS BECOME MORE DIVERGENT BETWEEN FRIDAY AND
SUNDAY...BUT THE CONSENSUS IS CONDITIONS WILL BE DRY AND WARMER
WITH TEMPERATURES NEAR AVERAGE FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 547 PM MDT SUN APR 13 2014
ONE HEAVIER BAND OF PRECIPITATION IS LEAVING THE EASTERN SECTIONS
OF THE AREA...AFFECTING THE KMCK TAF SITE...WITH ANOTHER BAND OF
LIGHT TO MODERATE SNOW MOVING OVER THE WESTERN HALF OF THE AREA AT
THIS TIME. AT KGLD...MVFR WITH OCCASIONAL IFR CONDITIONS ARE
EXPECTED THROUGH THE EVENING HOURS. THEN AFTER 06Z THE MVFR
CONDITIONS WILL BECOME VFR BY 15Z. GUSTY NORTH TO NORTHWEST WINDS
ARE EXPECTED THROUGH ALMOST IF NOT THE ENTIRE PERIOD.
AT KMCK...IFR CONDITIONS WILL BECOME MVFR AT AROUND 03Z. BY 06Z
THE MVFR CONDITIONS WILL RISE TO VFR AND CONTINUE FOR THE REST OF
THE PERIOD. THERE MAY BE A BIT OF A LULL IN THE GUSTY NORTH TO
NORTHWEST WINDS DURING THE OVERNIGHT HOURS. BUT JUST LIKE
KGLD...THE GUSTY WINDS SHOULD CONTINUE A MAJORITY OF THE PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT /1 AM CDT/ TONIGHT
FOR KSZ001-002-013.
CO...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR
COZ090>092.
NE...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT /1 AM CDT/ TONIGHT
FOR NEZ079-080.
&&
$$
UPDATE...BULLER
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
810 PM MDT SUN APR 13 2014
.UPDATE...
ISSUED AT 803 PM MDT SUN APR 13 2014
HAVE RECENTLY COMPLETED A COUPLE OF UPDATES. HAVE ALLOWED THE WIND
ADVISORY TO EXPIRE WITH WINDS BELOW CRITERIA. REST OF FORECAST
LOOKING ON TRACK. HAVE ADJUSTED WEATHER AND POPS TO REFLECT THE
TRENDS SEEN ON OBSERVATIONS...SATELLITE AND RADAR. WINTER WEATHER
ADVISORY DOING FINE WITH EXPECTED LIFT TO CONTINUE THROUGH MIDNIGHT.
EASTERN END OF THE ADVISORY MAY NOT GET TOO MUCH MORE SNOW BUT WILL
KEEP IT WITH THE EXPECTED INTENSITY OF SNOW COMBINED WITH WHAT HAS
ALREADY AND THE WINDY CONDITIONS.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 203 PM MDT SUN APR 13 2014
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW LARGE UPPER LEVEL
TROUGH ACROSS NORTHERN/CENTRAL US WITH TWO DISTINCT H5/H7
CIRCULATIONS OVER THE PLAINS AND CENTRAL ROCKIES. THE FIRST
CIRCULATION IS ASSOCIATED THE H5/H7 LOW NO OVER CENTRAL/EASTERN
NEBRASKA...RESPONSIBLE FOR DEFORMATION BAND OF SNOW THAT FORMED
OVER NORTHEAST COLORADO EARLY THIS MORNING AND IS NOW OVER THE
NORTHERN PART OF OUR CWA. THE SECOND CIRCULATION IS ASSOCIATE
WITH A SECOND CLOSED H7 LOW AND H5 TROUGH DEEPENING OVER WESTERN
COLORADO.
REGARDING WIND ADVISORY THIS AFTERNOON/EVENING...WINDS HAVE
STRUGGLED TO APPROACH CRITERIA THOUGH THEY HAVE BEEN NEAR ADVISORY
CRITERIA AT TIMES. THE PLAN IS TO HOLD ONTO THE ONGOING WIND
ADVISORY FOR A FEW MORE HOURS AS THE BEST PRESSURE RISES ARE
BEGINNING TO SHIFT TO THE SOUTH AND EAST...AND PROBABLY CANCEL THE
ADVISORY BEFORE 00Z.
REGARDING WINTER WEATHER ADVISORY...AS MENTIONED IN THE SYNOPSIS
THERE ARE TWO DISTINCT UPPER LEVEL CIRCULATIONS RESPONSIBLE FOR
BRINGING WINTRY WEATHER TO OUR CWA TODAY/TONIGHT. THE DEFORMATION
BAND ASSOCIATED WITH THE CIRCULATION OVER NEBRASKA SHOULD CONTINUE
TO TRANSITION NORTH AND EAST...WITH MAIN IMPACT OVER THE NORTHERN
PART OF THE CWA WINDING DOWN AROUND 00Z. I COULD SEE US CANCELING
THE NORTHERN PART OF THE ADVISORY EARLY (00Z-03Z) AS WE WILL LIKELY
NOT SEE ADVISORY CRITERIA MET UP NORTH WITH THE 2ND UPPER LOW. THE
SOUTHERN PART OF THE ADVISORY (KIT CARSON/CHEYENNE CO) HAVE
AVOIDED THE BRUNT OF THIS FIRST WAVE...HOWEVER THE SECOND
CIRCULATION WILL BEGIN TO BRING LIGHT TO MODERATE SNOW INTO
EASTERN COLORADO THIS EVENING AND THIS IS WHEN THESE LOCATIONS
MAY SEE THE GREATEST IMPACT. CONFIDENCE IS ACTUALLY HIGHER FOR KIT
CARSON/CHEYENNE CO TO MEET ADVISORY CRITERIA THIS EVENING THAN
SHERMAN. SHERMAN/WALLACE/GREELEY COULD BE CLOSE BASED ON LATEST
MODEL OUTPUT...HOWEVER CONFIDENCE IS TOO LOW TO ADD
WALLACE/GREELEY...OR CANCEL SHERMAN AT THIS POINT. WE WILL NEED TO
MONITOR NEAR TERM TRENDS. PRECIP SHOULD QUICKLY WIND DOWN THIS
EVENING IN THE NORTH AND THEN AFTER MIDNIGHT ACROSS THE
SOUTH...WITH MAYBE SNOW LINGERING THROUGH MID MORNING MONDAY IN
THE FAR SOUTH.
REGARDING ANTICIPATED IMPACTS THIS AFTERNOON/EVENING...ADDITIONAL
LIGHT SNOW ACCUMULATIONS ARE ANTICIPATED FOR MOST
LOCATIONS...HOWEVER MODERATE-HEAVY ACCUMULATIONS ARE MOST LIKELY
THIS EVENING OVER KIT CARSON/CHEYENNE COLORADO COUNTIES. WINDY
CONDITIONS WILL CONTINUE...AND WILL CONTINUE BRING BLOWING SNOW
CHANCES AND LOCALLY REDUCED VISIBILITIES THROUGH AROUND 03Z.
LATE TONIGHT/MONDAY TEMPS...HARD FREEZE IS LIKELY WITH SUB
FREEZING TEMPS ALREADY ACROSS MOST OF THE CWA...AND UPSTREAM TEMPS
IN THE 23-25F ALREADY BEING REPORTED. TOO EARLY IN THE SEASON TO
ISSUE FROST/FREEZE HIGHLIGHTS CONSIDERING CLIMATE NORMS FOR LAST
FROST/FREEZE. AIR MASS WILL BEGIN TO MODERATE SOME MONDAY...HOWEVER
HIGHS WILL REMAIN WELL BELOW NORMAL WITH VALUES IN THE 40S ACROSS
THE CWA.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 210 PM MDT SUN APR 13 2014
A SHORT WAVE RIDGE MOVES OVER THE ROCKIES AND FLATTENS AS IT MOVES
ACROSS THE HIGH PLAINS BETWEEN MONDAY NIGHT THROUGH TUESDAY
NIGHT. TEMPERATES WILL WARM AND CONDITIONS WILL DRY DURING THAT
TIME. BETWEEN LATE WEDNESDAY THROUGH THURSDAY NIGHT ANOTHER LOW
PRESSURE SYSTEM WILL MOVE THROUGH THE ROCKIES AND HIGH PLAINS
REGIONS...BRINGING ANOTHER ROUND OF COOLER TEMPERATURES AND A
CHANCE OF PRECIPITATION TO THE CENTRAL HIGH PLAINS. A MIXTURE OF
RAIN AND SNOW IS EXPECTED WITH THIS SYSTEM.
MODEL SOLUTIONS BECOME MORE DIVERGENT BETWEEN FRIDAY AND
SUNDAY...BUT THE CONSENSUS IS CONDITIONS WILL BE DRY AND WARMER
WITH TEMPERATURES NEAR AVERAGE FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 547 PM MDT SUN APR 13 2014
ONE HEAVIER BAND OF PRECIPITATION IS LEAVING THE EASTERN SECTIONS
OF THE AREA...AFFECTING THE KMCK TAF SITE...WITH ANOTHER BAND OF
LIGHT TO MODERATE SNOW MOVING OVER THE WESTERN HALF OF THE AREA AT
THIS TIME. AT KGLD...MVFR WITH OCCASIONAL IFR CONDITIONS ARE
EXPECTED THROUGH THE EVENING HOURS. THEN AFTER 06Z THE MVFR
CONDITIONS WILL BECOME VFR BY 15Z. GUSTY NORTH TO NORTHWEST WINDS
ARE EXPECTED THROUGH ALMOST IF NOT THE ENTIRE PERIOD.
AT KMCK...IFR CONDITIONS WILL BECOME MVFR AT AROUND 03Z. BY 06Z
THE MVFR CONDITIONS WILL RISE TO VFR AND CONTINUE FOR THE REST OF
THE PERIOD. THERE MAY BE A BIT OF A LULL IN THE GUSTY NORTH TO
NORTHWEST WINDS DURING THE OVERNIGHT HOURS. BUT JUST LIKE
KGLD...THE GUSTY WINDS SHOULD CONTINUE A MAJORITY OF THE PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT /1 AM CDT/ TONIGHT
FOR KSZ001>004-013.
CO...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR
COZ090>092.
NE...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT /1 AM CDT/ TONIGHT
FOR NEZ079>081.
&&
$$
UPDATE...BULLER
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
555 PM MDT SUN APR 13 2014
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 203 PM MDT SUN APR 13 2014
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW LARGE UPPER LEVEL
TROUGH ACROSS NORTHERN/CENTRAL US WITH TWO DISTINCT H5/H7
CIRCULATIONS OVER THE PLAINS AND CENTRAL ROCKIES. THE FIRST
CIRCULATION IS ASSOCIATED THE H5/H7 LOW NO OVER CENTRAL/EASTERN
NEBRASKA...RESPONSIBLE FOR DEFORMATION BAND OF SNOW THAT FORMED
OVER NORTHEAST COLORADO EARLY THIS MORNING AND IS NOW OVER THE
NORTHERN PART OF OUR CWA. THE SECOND CIRCULATION IS ASSOCIATE
WITH A SECOND CLOSED H7 LOW AND H5 TROUGH DEEPENING OVER WESTERN
COLORADO.
REGARDING WIND ADVISORY THIS AFTERNOON/EVENING...WINDS HAVE
STRUGGLED TO APPROACH CRITERIA THOUGH THEY HAVE BEEN NEAR ADVISORY
CRITERIA AT TIMES. THE PLAN IS TO HOLD ONTO THE ONGOING WIND
ADVISORY FOR A FEW MORE HOURS AS THE BEST PRESSURE RISES ARE
BEGINNING TO SHIFT TO THE SOUTH AND EAST...AND PROBABLY CANCEL THE
ADVISORY BEFORE 00Z.
REGARDING WINTER WEATHER ADVISORY...AS MENTIONED IN THE SYNOPSIS
THERE ARE TWO DISTINCT UPPER LEVEL CIRCULATIONS RESPONSIBLE FOR
BRINGING WINTRY WEATHER TO OUR CWA TODAY/TONIGHT. THE DEFORMATION
BAND ASSOCIATED WITH THE CIRCULATION OVER NEBRASKA SHOULD CONTINUE
TO TRANSITION NORTH AND EAST...WITH MAIN IMPACT OVER THE NORTHERN
PART OF THE CWA WINDING DOWN AROUND 00Z. I COULD SEE US CANCELING
THE NORTHERN PART OF THE ADVISORY EARLY (00Z-03Z) AS WE WILL LIKELY
NOT SEE ADVISORY CRITERIA MET UP NORTH WITH THE 2ND UPPER LOW. THE
SOUTHERN PART OF THE ADVISORY (KIT CARSON/CHEYENNE CO) HAVE
AVOIDED THE BRUNT OF THIS FIRST WAVE...HOWEVER THE SECOND
CIRCULATION WILL BEGIN TO BRING LIGHT TO MODERATE SNOW INTO
EASTERN COLORADO THIS EVENING AND THIS IS WHEN THESE LOCATIONS
MAY SEE THE GREATEST IMPACT. CONFIDENCE IS ACTUALLY HIGHER FOR KIT
CARSON/CHEYENNE CO TO MEET ADVISORY CRITERIA THIS EVENING THAN
SHERMAN. SHERMAN/WALLACE/GREELEY COULD BE CLOSE BASED ON LATEST
MODEL OUTPUT...HOWEVER CONFIDENCE IS TOO LOW TO ADD
WALLACE/GREELEY...OR CANCEL SHERMAN AT THIS POINT. WE WILL NEED TO
MONITOR NEAR TERM TRENDS. PRECIP SHOULD QUICKLY WIND DOWN THIS
EVENING IN THE NORTH AND THEN AFTER MIDNIGHT ACROSS THE
SOUTH...WITH MAYBE SNOW LINGERING THROUGH MID MORNING MONDAY IN
THE FAR SOUTH.
REGARDING ANTICIPATED IMPACTS THIS AFTERNOON/EVENING...ADDITIONAL
LIGHT SNOW ACCUMULATIONS ARE ANTICIPATED FOR MOST
LOCATIONS...HOWEVER MODERATE-HEAVY ACCUMULATIONS ARE MOST LIKELY
THIS EVENING OVER KIT CARSON/CHEYENNE COLORADO COUNTIES. WINDY
CONDITIONS WILL CONTINUE...AND WILL CONTINUE BRING BLOWING SNOW
CHANCES AND LOCALLY REDUCED VISIBILITIES THROUGH AROUND 03Z.
LATE TONIGHT/MONDAY TEMPS...HARD FREEZE IS LIKELY WITH SUB
FREEZING TEMPS ALREADY ACROSS MOST OF THE CWA...AND UPSTREAM TEMPS
IN THE 23-25F ALREADY BEING REPORTED. TOO EARLY IN THE SEASON TO
ISSUE FROST/FREEZE HIGHLIGHTS CONSIDERING CLIMATE NORMS FOR LAST
FROST/FREEZE. AIR MASS WILL BEGIN TO MODERATE SOME MONDAY...HOWEVER
HIGHS WILL REMAIN WELL BELOW NORMAL WITH VALUES IN THE 40S ACROSS
THE CWA.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 210 PM MDT SUN APR 13 2014
A SHORT WAVE RIDGE MOVES OVER THE ROCKIES AND FLATTENS AS IT MOVES
ACROSS THE HIGH PLAINS BETWEEN MONDAY NIGHT THROUGH TUESDAY
NIGHT. TEMPERATES WILL WARM AND CONDITIONS WILL DRY DURING THAT
TIME. BETWEEN LATE WEDNESDAY THROUGH THURSDAY NIGHT ANOTHER LOW
PRESSURE SYSTEM WILL MOVE THROUGH THE ROCKIES AND HIGH PLAINS
REGIONS...BRINGING ANOTHER ROUND OF COOLER TEMPERATURES AND A
CHANCE OF PRECIPITATION TO THE CENTRAL HIGH PLAINS. A MIXTURE OF
RAIN AND SNOW IS EXPECTED WITH THIS SYSTEM.
MODEL SOLUTIONS BECOME MORE DIVERGENT BETWEEN FRIDAY AND
SUNDAY...BUT THE CONSENSUS IS CONDITIONS WILL BE DRY AND WARMER
WITH TEMPERATURES NEAR AVERAGE FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 547 PM MDT SUN APR 13 2014
ONE HEAVIER BAND OF PRECIPITATION IS LEAVING THE EASTERN SECTIONS
OF THE AREA...AFFECTING THE KMCK TAF SITE...WITH ANOTHER BAND OF
LIGHT TO MODERATE SNOW MOVING OVER THE WESTERN HALF OF THE AREA AT
THIS TIME. AT KGLD...MVFR WITH OCCASIONAL IFR CONDITIONS ARE
EXPECTED THROUGH THE EVENING HOURS. THEN AFTER 06Z THE MVFR
CONDITIONS WILL BECOME VFR BY 15Z. GUSTY NORTH TO NORTHWEST WINDS
ARE EXPECTED THROUGH ALMOST IF NOT THE ENTIRE PERIOD.
AT KMCK...IFR CONDITIONS WILL BECOME MVFR AT AROUND 03Z. BY 06Z
THE MVFR CONDITIONS WILL RISE TO VFR AND CONTINUE FOR THE REST OF
THE PERIOD. THERE MAY BE A BIT OF A LULL IN THE GUSTY NORTH TO
NORTHWEST WINDS DURING THE OVERNIGHT HOURS. BUT JUST LIKE
KGLD...THE GUSTY WINDS SHOULD CONTINUE A MAJORITY OF THE PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT /1 AM CDT/ TONIGHT
FOR KSZ001>004-013.
WIND ADVISORY UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR
KSZ014>016-027>029-041-042.
CO...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR
COZ090>092.
NE...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT /1 AM CDT/ TONIGHT
FOR NEZ079>081.
&&
$$
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS TOPEKA KS
619 PM CDT Sun Apr 13 2014
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Monday)
Issued at 326 PM CDT SUN APR 13 2014
20Z water vapor imagery shows a shortwave lifting across eastern
KS as another wave digs south towards the four corners region.
This initial wave has sparked a line of thunderstorms to form
along a cold front that is surging southeast through the forecast
area. Much of the short range guidance is pointing towards the
convection to be east of the forecast area by 7 pm, which fits in
with current radar trends. Therefore have lowered pops for this
evening and removed mention of thunder. There is a band of snow
across NEB. The HRRR and RAP suggest the tail end of this precip
may move east along the NEB state line through the evening as the
first shortwave lifts northeast. Precip accumulations with this
should be fairly light as the better mid level frontogenesis stays
mainly to the north. However as the second shortwave comes out of
the Rockies late tonight and through the morning Monday, this
frontogenetical band redevelops south and most guidance is
pointing at a band of snow moving over east central KS. The
frontogenesis looks strong enough for a decent band of snow and
possible accumulations around an inch through late morning Monday.
This will be highly dependent on the intensity of the snowfall
however since ground temps remain relatively warm. If the band
produces higher snowfall rates, some parts of east central KS
could see accumulations a little higher.
In between the convection this afternoon and the frontogenetical
precip overnight, think there will be a lull in the precip and
have tapered pops down this evening. Models show saturation in the
lower levels hinting at the possibility for some drizzle which
could be freezing depending on surface temps. However the
conditions for drizzle do not look to persist for long as some mid
level drying occurs before the next shortwave moves in and
saturates the column. Overall am not to excited about the
prospects for drizzle but can`t rule out the chance so will
include a mention in the forecast.
Lows tonight should fall into the lower 30s due to strong cold air
advection behind the front. Temps in central NEB have already
fallen into the upper 20s suggesting my lows may not be cool
enough. In any case, freezing temps look likely tonight and will
issue as freeze warning as we have entered the locally defined
growing season. Cold air advection persists through the morning
Monday so highs are not expected to warm much. However think
clouds will eventually clear out by the afternoon so some
insolation may help to warm highs into the 40s.
.LONG TERM...(Monday Night through Sunday)
Issued at 326 PM CDT SUN APR 13 2014
Monday night through Wednesday looks dry as the central plains see
dry northwest flow develop ahead of the next wave expected to dig
into the plains by Thursday. The medium range models seem to be in
some agreement with timing of the next wave therefore have trended
pops up for Thursday and Thursday night. There does not appear to
be much instability with this system as warm moist are is slow to
return. However there does appear to be another shot of cold air
moving in Thursday night which could cause a brief change over to
snow before the precip comes to an end. Therefore have maintained
a mention of rain and snow for Thursday night.
While less certain, there are indications of a southern stream
wave trying to phase with a northern stream wave over the area
Sunday. Confidence is low since the GFS struggles to advect
moisture this far north. However with the ECMWF breaking out some
QPF, will insert some low (20-30%) POPs Saturday night and Sunday.
A hard freeze looks likely Tuesday morning as skies clear out and
surface ridging moves over the region. Therefore have continued
with lows in the lower to middle 20s and will post a freeze
warning through Tuesday morning too. Southerly flow returns for
Wednesday helping to moderate the cool temps before the next cold
front moves in Thursday and knocks temps back down into the 40s
and 50s for Thursday and Friday. With a split flow for the weekend
and the northern stream remaining north, temps should moderate
into the 60s for the weekend.
&&
.AVIATION...(For the 00Z TAFs through 00Z Monday Evening)
Issued at 613 PM CDT SUN APR 13 2014
MVFR conditions should persist through for the remainder of
tonight. A band of snow will develop over south central KS early
tomorrow morning and move northeast towards the taf sites. Have
adjusted the timing slightly from previous forecast. There could
be a brief period of moderate to heavy snow that would cause IFR
vis but confidence for that occurring is low at this point.
Conditions should improve to VFR after the snow band exits the
taf sites.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING from Midnight tonight to 10 AM CDT Monday FOR
KSZ008>012-020>024-026-034>040-054>056-058-059.
FREEZE WARNING from 11 PM Monday to 9 AM CDT Tuesday FOR
KSZ008>012-020>024-026-034>040-054>056-058-059.
WIND ADVISORY until 9 PM CDT this evening FOR KSZ008>010-020-021-
034.
&&
$$
SHORT TERM...Wolters
LONG TERM...Wolters
AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS TOPEKA KS
342 PM CDT Sat Apr 12 2014
.SHORT TERM...(This Evening through Sunday)
Issued at 342 PM CDT SAT APR 12 2014
20Z water vapor imagery and profiler data shows a weak wave moving
through the central plains while a shortwave over the southwest
moves into AZ and a second shortwave digs southeast through the
Pacific northwest. Surface obs show an inverted trough just to the
west of the forecast area across central and southwest KS. Strong
southerly winds continue to bring dewpoints in the upper 50s and
lower 60s north into eastern KS. A dryline was noted from western OK
into central KS near Kingman up to near Elsworth.
The main question for this evening is whether a surface parcel will
be able to break through an impressive elevated mixed layer (EML)
that the 18Z NAM shows is still providing 60 to 100 J/kg of CIN just
east of the dryline. The latest high resolution models are still
trying to generate an isolated storm of two off the dryline during
the next hour or two and lift it into northeast KS. Shear profiles
continue to look unimpressive, but with CAPE values on the order of
2500 J/kg, there would be a hail risk if an updraft were able to get
going. At this point am thinking the cap may end up being to strong
since convergence along the dryline is minor and a weak shortwave is
the only real forcing to break the cap. Even at 20Z there is not
much of a CU field along the dryline to speak of either. So
attention turns to the inverted trough to the north and whether
storms can back build into northeast KS. The surface boundary across
IA is further north than previous models had progged with the best
low level convergence across northeast IA. So in general precip
chances look highly dependent on whether a storm or two forms off
the dryline. Because of this have trended POPs lower for tonight.
Lows will be mild for much of the area as southerly winds continue
to bring warm air into the forecast area. The exception may be over
Far north central KS where the trough/front could slip south
shifting the winds to the northeast and allow temps to fall into the
mid 50s.
For Sunday, there should be much better lift and forcing for precip
as the shortwave over the southwest is kicked east and the frontal
boundary pushes southeast. Increasing clouds suggest the
destabilization could be limited ahead of the front and the models
show less instability with the cold front. Additionally deep layer
shear continues to look marginal. Think there will be a broken line
of showers and storms with the front and have continued with
categorical wording in eastern KS through the afternoon. There may
also be enough instability for some of the stronger storms to produce
hail. There should be a modest warm up of 5 or 10 degrees Sunday
before strong cold air advection kicks in and causes temps to fall
behind the front. There may also be a brief period where winds could
reach advisory levels across north central KS late in the afternoon.
Some of the models are showing the potential for gusts up to 40KT.
Opted to hold off on any advisory at this time since it appears to
be a small window where winds would exceed advisory levels and
confidence in the overall model performance is only average.
.LONG TERM...(Sunday Night through Saturday)
Issued at 342 PM CDT SAT APR 12 2014
Several challenges Sunday night into Monday night, including
precipitation chances and types, temperatures, and wind speeds.
Initial upper wave and cold front should exit the east and
southeast early in the evening with next surge of upper forcing
via the next wave aloft coming into the western and central
portions overnight. The NAM continues to be a rather slow and also
deeper solution with the secondary wave, with colder air
throughout the column keeping saturation deeper and heavier/longer
duration precipitation chances. With the split flow continuing and
energy bifurcating along it to the northwest, nailing down
specifics of the forcing and vertical profiles is difficult, but
still believe the NAM is hard to swallow and will rely on the
larger domain solutions again. In this scenario, low and mid
levels dry out Sunday night into Monday morning, keeping amounts
light and highs still reaching the mid and upper 40s Monday.
Although ice crystal formation could still be difficult, with
soundings falling below freezing through the column, still looks
to be a several hour window of light snowfall potential. Given the
warmth of recent days and likely wet ground, any accumulations
should be limited to grassy surfaces. Stout pressure gradient and
diurnally high mixing heights could present a wind advisory
concern Sunday night and perhaps into early Monday, but given this
rare occurrence frequency and aforementioned uncertainty, will
hold off on any headlines at this point. Freezing temperatures
look to impact western and northern locations briefly Sunday night
and the entire area for many hours Monday night as the surface
ridge passes under clear skies.
Zonal flow brings south winds back rather quickly Tuesday and
Wednesday with limited initial moisture return behind the early week
anticyclone. Could see some fire weather concerns here. Next
precipitation chance still on track for the late week, but
considerable uncertainty here too with split flow persisting. Some
consistency in Thursday and Thursday night for chance PoPs here. How
much cold air comes in then for Friday is tricky, but should see
some moderation for Saturday.
&&
.AVIATION...(For the 18Z TAFs through 18Z Sunday Afternoon)
Issued at 1226 PM CDT SAT APR 12 2014
Confidence in thunderstorms impacting the terminals this afternoon
or this evening is diminishing. Latest NAM12 and RAP13 continue to
show a decent elevated mixed layer capping the boundary layer with
only a weak wave providing any forcing. Any low level convergence
looks to remain well north along a trough axis/front in southern
NEB and IA. And the latest HRRR suggests that maybe an isolated
storm or two will be able to break the cap due to daytime heating.
Because of this will not mention any TS in the forecast at this
time. Additionally any lower CIGS from the models seems to be tied
to a potential MCS moving south. With the increasing CIN overnight
and a veered low level jet, am a little suspicious of the NAM and
especially the GFS which has not had a handle on the low level
moisture now since it began to advect north. Therefore will keep
the forecast VFR overnight. Think deteriorating conditions with
precip is most likely with the eventual FROPA which looks to
affect the terminals early Sunday afternoon.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...65
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS WICHITA KS
303 PM CDT SAT APR 12 2014
.SYNOPSIS...
ISSUED AT 258 PM CDT SAT APR 12 2014
UPPER LEVEL ANALYSIS THROUGH 18Z SHOWS A DEEPENING DISTURBANCE
MOVING INTO SOUTHERN CALIFORNIA. A SECOND DEEPENING DISTURBANCE IS
MOVING SOUTH ACROSS THE PACIFIC NORTHWEST. THESE TWO SYSTEMS WILL
BE THE MAIN WEATHER PRODUCERS OVER THE NEXT SEVERAL DAYS.
CURRENT SURFACE ANALYSIS AT 18Z SHOWS LOW PRESSURE CENTERED OVER
WESTERN KANSAS...WITH A STATIONARY BOUNDARY EXTENDING UP INTO
WESTERN IOWA. THE DRYLINE EXTENDS FROM KDDC TO EAST OF KHHF...AND
IT APPEARS TO HAVE JUST GONE THROUGH KGAG. LOW LEVEL MOISTURE HAS
INCREASED ACROSS THE REGION WITH DEWPOINTS HAVING RISEN TO AROUND 60
DURING THE 15-17Z TIME FRAME...BUT 18Z DATA SHOWING SOME DRYING OUT FROM
MIXING.
COOK
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 258 PM CDT SAT APR 12 2014
THE 17Z RAP ANALYSIS SHOWS 0-6KM SHEAR VALUES IN THE LOWER 30 KNOT
RANGE ACROSS THE FORECAST AREA...WITH MLCAPES AROUND 1000 J/KG.
12.15Z RAP FORECAST OF THESE FIELDS SHOWS AN INCREASE IN DEEP LAYER
SHEAR AS THE LOW LEVEL JET DEVELOPS THIS EVENING. MLCAPE VALUES MAX
OUT AROUND 2000 J/KG THIS AFTERNOON DURING PEAK HEATING...WITH
DEWPOINT DEPRESSIONS REACHING OVER 25 DEGREES.
AT THIS TIME...NOT THAT EXCITED FOR AFTERNOON CONVECTION ACROSS THE
FORECAST AREA...THERE IS JUST TOO MUCH OF A CAP IN PLACE. THE 15Z
HRRR DOES PRODUCE SOME CONVECTION OVER THE FORECAST AREA ALONG THE
DRYLINE AFTER 00Z...AS DOES THE 12.12Z WRF-NMM. THIS IS MAINLY EAST
OF HIGHWAY 14 AND NORTH OF HIGHWAY 400. AT THAT TIME...THE DEEP
LAYER SHEAR WILL BE ENOUGH FOR ORGANIZED STORMS. THIS IS ALSO THE
BEST TIME FOR A TORNADO THREAT GIVEN THAT DEWPOINT DEPRESSIONS WILL
HAVE COME DOWN BY THEN...JUST NOT SURE THEY WILL HAVE COME DOWN
ENOUGH. CONFIDENCE IN A TORNADO THREAT IS LOW.
WE ARE LOOKING AT DISCREET SUPERCELLS...WITH THE MAIN THREAT BEING
LARGE HAIL. BELIEVE THE LARGE HAIL THREAT IS QUITE HIGH GIVEN THAT
THERE WILL BE LITTLE CHANCE FOR ANVIL SEEDING AND THE 0-10KM SHEAR
IS GREATER THAN 90 KNOTS. THINK THAT BASEBALL HAIL OR LARGER AS A
MAX HAIL SIZE IS POSSIBLE FOR ANY ISOLATED SUPERCELL ALONG THE
SOUTHERN PERIPHERY OF THE DEVELOPMENT AREA. IT WILL BE INTERESTING
TO SEE HOW THIS PANS OUT.
TONIGHT...A COLD FRONT WILL MOVE INTO THE REGION...SLOWLY ADVANCING
TO THE SOUTHEAST. THIS WILL CREATE A COMPLEX WEATHER SCENARIO FOR
SUNDAY THROUGH MONDAY.
BEHIND THE FRONT...STRONG NORTHERLY WINDS WILL MOVE IN AS IT
PASSES. BUFKIT MOMENTUM TRANSPORT SUGGESTS WINDS OF 30 MPH WITH
GUSTS TO 45 MPH.
BY SUNDAY AT 18Z...THE FRONT WILL BE APPROXIMATELY LOCATED FROM
EMPORIA TO WINFIELD. THE BEST CHANCE OF CONVECTION WILL BE ALONG
AND EAST OF THE FRONT...MAINLY ACROSS SOUTHEAST KANSAS. MOISTURE IN
THE LOW LEVELS SHOULD BE MORE FAVORABLE FOR STORM DEVELOPMENT...AS
WILL FORCING IN THE MID-LEVELS. FAVORABLE SHEAR/BUOYANCY
COMBINATIONS...WITH MEAN WIND VECTORS MORE PARALLEL TO THE SURFACE
BOUNDARY SUGGESTS A RAPID DEVELOP OF STORMS...WITH STORMS BEING
ORGANIZED INTO A LINEAR FASHION. THEREFORE...THE MAIN THREAT FOR
SEVERE WEATHER SHOULD BE DAMAGING WIND...WITH LARGE HAIL A SECONDARY
THREAT.
AS SAID EARLIER...AS THE FRONT EXITS...STRONG NORTHERLY WINDS MOVE
IN. TO FURTHER COMPLICATE MATTERS...STRONG COLD ADVECTION MOVES
INTO THE REGION AS WELL. SUNDAY NIGHT...THERE WILL BE A
PRECIPITATION TYPE PROBLEM AS THE COLD AIR MOVES IN. SOUNDINGS
SUGGESTS A CHANGE TO SNOW NORTH OF HIGHWAY 50 BY MONDAY
MORNING...WITH A MIX FURTHER SOUTH. ACCUMULATIONS ARE CERTAINLY
POSSIBLE...BUT NOT SIGNIFICANT. BUFKIT SOUNDING DATA FROM THE 12Z
GFS SUGGESTS THE WIND COULD LAST INTO THE MORNING HOURS OF TUESDAY.
HIGH PRESSURE MOVES INTO THE REGION...WITH MONDAY NIGHT IN LINE FOR
A REASONABLE FROST/FREEZE SCENARIO. WITH ALL THE COMPLEX WEATHER
GOING ON AHEAD OF THIS THREAT...WILL LEAVE THIS FOR LATTER SHIFTS TO
CONTEMPLATE.
COOK
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 258 PM CDT SAT APR 12 2014
ANOTHER STORM SYSTEM MOVES INTO POSITION...STRETCHING FROM THE HIGH
PLAINS INTO THE UPPER MISSISSIPPI RIVER VALLEY WEDNESDAY. THIS
SUGGESTS STRONG SOUTHERLY WINDS ACROSS THE REGION DUE TO A
TIGHTENING PRESSURE GRADIENT. THIS WILL UNDOUBTEDLY BE A DANGEROUS
DAY FOR FIRES.
MOISTURE ADVECTION RETURNS INTO THE REGION WEDNESDAY NIGHT AND
THURSDAY AS THE GULF OPENS. AT THIS TIME...THIS SYSTEM IS LOOKING
RATHER STRONG AND COULD BRING SEVERE WEATHER INTO THE REGION FOR THE
LATTER PORTION OF THE WEEK GIVEN THE FAVORABLE SHEAR/BUOYANCY
COMBINATIONS AT THIS TIME. HIGH PRESSURE THEN MOVES INTO THE REGION
THEREAFTER.
COOK
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 135 PM CDT SAT APR 12 2014
A BRIEF PERIOD OF MORNING STRATUS AT KICT...KHUT AND KCNU HAS
GIVEN WAY TO VFR CONDITIONS THIS AFTERNOON. GUST SOUTH TO
SOUTHWEST WINDS WILL BE THE MAIN AVIATION CONCERN THROUGH THE
AFTERNOON HOURS...WITH THE THREAT OF CONVECTION RAMPING UP BETWEEN
23-01 UTC. FORECAST SOUNDING INDICATING DECENT MID-LEVEL
LAPSE RATES...HOWEVER LOW LEVEL MOISTURE IS SHALLOW AND FURTHER
MIXING WILL NOT AID THAT SITUATION. FORECAST SOUNDINGS AND MESO MODELS
CONTINUE TO HINT THAT AT LEAST ISOLATED STORMS WILL FIRE VICINITY
OF KHUT AND KSLN. CONFIDENCE THAT STORMS ACTUALLY WILL FIRE IS
RATHER LOW...BUT WILL MAINTAIN CB AND VCTS FOR THE TIME BEING. ANY
STORMS THAT DEVELOP WILL MOVE EAST NORTHEAST OUT OF THE CWA
BETWEEN 03 AND 06 UTC. COLD FRONT AND SURFACE LOW WILL MOVE INTO CENTRAL
KANSAS BETWEEN 04-O6 UTC...WITH CHANCE OF MVFR CIGS SPREADING INTO
BOTH KRSL AND KSLN BY 12 UTC.
&&
.FIRE WEATHER...
ISSUED AT 258 PM CDT SAT APR 12 2014
THE NEXT REAL FIRE WEATHER CONCERN FOR GRASSLAND WILL NOT BE UNTIL
WEDNESDAY. THAT IS WHEN STRONG SOUTHERLY WINDS DEVELOP ACROSS THE
AREA FROM THE SOUTHWEST AS A RESULT OF AN INCREASING PRESSURE
GRADIENT.
THAT SAID...THERE IS A GOOD CHANCE OF RAINFALL SUNDAY AND INTO
MONDAY. THIS WITH MILD TEMPERATURES RETURNING TO THE REGION TOWARD
THE END OF THE WEEK...SHOULD SPURN MORE GROWTH OF GRASSES...AS WE
TREND TOWARD LESSER CURING.
COOK
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 64 76 32 45 / 20 80 50 40
HUTCHINSON 61 74 30 45 / 20 70 50 40
NEWTON 63 74 30 44 / 30 80 50 40
ELDORADO 64 76 32 44 / 20 80 50 40
WINFIELD-KWLD 66 78 34 46 / 20 80 50 40
RUSSELL 55 59 29 46 / 20 60 50 10
GREAT BEND 56 61 28 46 / 20 50 50 20
SALINA 60 67 30 46 / 30 70 50 20
MCPHERSON 60 70 29 45 / 30 70 50 30
COFFEYVILLE 65 74 36 45 / 10 80 70 30
CHANUTE 64 73 35 43 / 10 80 70 40
IOLA 63 73 34 43 / 20 80 70 40
PARSONS-KPPF 64 73 36 44 / 10 80 70 40
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 9 AM TO 7 PM CDT SUNDAY FOR KSZ032-033-047-
048.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1226 PM CDT Sat Apr 12 2014
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 429 AM CDT SAT APR 12 2014
Early Saturday morning, a short wave trough was moving across the
northern Plains with a surface low moving along the NE/SD border
and a cold front extending southwest across western Nebraska.
Meanwhile, a broad trough was in place over the western CONUS with
a closed low drifting east across southern California. Surface low
pressure was deepening over southeast Colorado with a broad 40 to
60 kt low level jet across the southern and central Plains.
Moisture advection was in full swing, with mid-50s surface
dewpoints into the local area by 3 AM and low-60s dewpoints in
central Oklahoma. By late afternoon today, expect the surface low
to deepen and drift east into SW Kansas while a surface
trough/cold front extends northeast into SE Nebraska. A dryline
seems likely to set up just west of a Salina to Wichita line
(although RAP/HRRR are intent in mixing the dry air well into
eastern KS...likely incorrectly) with increased definition with
southward extent. A low level thermal axis should point from the
surface low NE toward Salina where it will intersect the dryline
with slightly backed surface winds just south of this axis. High
temperatures today are likely to climb into the lower 80s with
south winds gusting to 30+ mph especially south of I-70.
Minor details of the pre-convective environment on Saturday are
going to have substantial impacts on overall convective coverage and
intensity. Perhaps the most important detail is the quality of low
level moisture and it`s impact on parcels ability to overcome the
late day cap. Surface Td greater than 60, or even 62, would
indicated a much better chance for late day initiation along the
dryline than Td`s in the 50s. Timing of a weak short wave will also
play a role in weakening the cap between 00Z and 03Z. If this weak
wave can adequately cool the capping inversion coincident with peak
instability, initiation would become much more likely than if it is
a bit slower to pass through. If storms are able to develop, the
strength of the mid level wind fields comes into question. A
weakness in the wind fields is forecast to be present between 21Z
and 01Z, and shear profiles may not be sufficient for supercell
development within this weakness, making storm persistence more
difficult. However, the wind profiles are forecast to rapidly
improve with stronger low and mid level winds by 03Z... favoring
supercell structures in any convection ongoing by that time.
The most likely scenario to play out seems to be a warm sector
characterized by 2000 to 3000 J/kg of MLCAPE with 0-6 shear in the
25 to 35 kt range by 00Z. One area of thunderstorm development will
be favored in SW Iowa late this afternoon, and will probably see
this activity develop southwest into NE Kansas along the cold
front/sfc trough, although this may not occur until evening as the
short wave trough moves over and the LLJ intensifies and impinges
upon the boundary. Large hail would be the primary threat with this
activity, especially if embedded supercell structure develops.
Damaging winds would also be possible especially near the front
through evening while the tornado threat will be near zero. Another
area of convection, much more conditional in terms of development,
may initiate near the intersection of the dryline and cold front/sfc
trough currently forecast to be in the general Salina area. This is
in an area of enhanced low level convergence and a relative minimum
in CINH. Any storms that develop in this area would seem likely to
take on supercell characteristics with a main threat being very
large hail with such steep mid level lapse rates and strong
instability. LCL`s are expected to be rather high and the tornado
threat appears very low, although these conditions would also pose
at least some potential for damaging winds. Some guidance suggests
these storms could move east and track south of I-70 for a while but
increasing inhibition would likely kill the storms before getting
too far into eastern KS.
As the night continues, expect the primary convective focus to be
across northern KS, north of the effective surface front and likely
shifting north with time as the front lifts north during the early
morning. Overall convective coverage in KS through the night is
questionable, but seem to at least have a persistent focus north of
I-70 where the LLJ impinges on the front amidst elevated instability
and favorable shear profiles for organized storms. May continue a
large hail threat...or even isolated damaging winds...through the
night but decreasing with time.
.LONG TERM...(Sunday through Friday)
Issued at 429 AM CDT SAT APR 12 2014
By Sunday morning, the broad mid-level trough will be stretched
across much of the northern and central U.S., with models in good
agreement that there will be two embedded shortwave troughs within
the large wave. At the surface, there are still some model
discrepancies with the speed of the cold front through the region on
Sunday. In general, the cold front looks to be stretched across
north central Kansas by 12z Sun and should exit southeast of the
area between 21z-00z. The exact timing of this frontal passage will
have an impact on temperatures as strong southerly winds ahead of
the front should keep temperatures mild across far east central
Kansas while winds should quickly back to the northwest and become
breezy behind the front, ushering much cooler air into the region.
As a result, north central Kansas will likely experience their high
temperatures first thing in the morning with falling temperatures
through the remainder of the day. At this time, have a large spread
for highs Sunday, ranging from the upper 50s to lower 70s.
The first of the embedded mid-level shortwaves looks to track
eastward across the region on Sunday, helping to provide additional
forcing. Should see some scattered showers and thunderstorms
developing along and behind the cold front during the morning,
becoming more organized and likely intensifying through the
afternoon as the front progresses eastward over the area. By Sunday
afternoon, models show MUCAPE values reaching into the 1500-2000J/kg
range across east central Kansas with 0-6km bulk shear potentially
reaching upwards of 30-40kts. With these conditions in place near
the front, some of these storms could become strong to severe, with
large hail and strong winds being the primary threats. It`s worth
noting that the models show deep unidirectional shear along the
boundary, so could see these thunderstorms congeal into a line
during the afternoon and may also see periods of heavy rain,
especially across east central Kansas, with precipitable water
values potentially reaching near 1.20-1.30 inches. As the front
moves out of the area by around 00z, any lingering thunderstorms
across east central Kansas should become elevated.
By Sunday night, there is still some uncertainty with regards to how
much precipitation will still be in place across the area into
Monday morning. The second embedded mid-level shortwave will dive
southward across the High Plains Sunday night, but there are model
discrepancies with the location of the moisture associated with this
wave. The GFS/ECMWF show some drier air moving over the area with
the moisture from the shortwave remaining mostly to the south and
west, possibly clipping the far southern CWA. The NAM/GEM on the
other hand don`t push the moisture as far south and have it tracking
across much of the CWA Sunday night through Monday. Have trended
more toward the GFS/ECMWF and have trimmed PoPs back some Sunday night
into Monday morning with dry conditions by Monday afternoon.
However, with the cold air surging into the region behind the cold
front, low temperatures look to drop into the low/mid 30s so any
lingering light precipitation during this period could transition
over to a mix of rain and snow. In trending more with the drier
solutions, do not anticipate any snow accumulations at this time.
Surface high pressure moves in on Monday behind the exiting system,
with breezy northerly winds keeping conditions nearly 15-20F degrees
cooler than normal with highs only into the middle 40s. The center
of the surface high looks to track directly over the region Monday
night, resulting in very cold conditions with low temperatures
plunging below freezing into the mid/upper 20s. As a result, could
potentially be looking at freeze headlines for Tuesday morning.
As the mid-level trough advances toward the east coast,
fairly zonal flow sets up through mid week with conditions remaining
dry. With the surface high shifting east of the area and winds
shifting to the southwest, temperatures should quickly rebound back
into the 50s and 60s for Tuesday and Wednesday. Models show the next
mid-level trough developing over the northern Rockies on Wednesday,
however there are large model discrepancies with how this wave is
handled as to progresses into the central U.S., with the ECMWF
having the trough skim across the area Thu/Thu night while the GFS
has a closed low develop and tracks it directly over the CWA. With
these vast model differences, didn`t make too many adjustments to
the consensus blend for the end of the week except to trim PoPs back
to only slights for Thu/Thu night due to the model uncertainty.
&&
.AVIATION...(For the 18Z TAFs through 18Z Sunday Afternoon)
Issued at 1226 PM CDT SAT APR 12 2014
Confidence in thunderstorms impacting the terminals this afternoon
or this evening is diminishing. Latest NAM12 and RAP13 continue to
show a decent elevated mixed layer capping the boundary layer with
only a weak wave providing any forcing. Any low level convergence
looks to remain well north along a trough axis/front in southern
NEB and IA. And the latest HRRR suggests that maybe an isolated
storm or two will be able to break the cap due to daytime heating.
Because of this will not mention any TS in the forecast at this
time. Additionally any lower CIGS from the models seems to be tied
to a potential MCS moving south. With the increasing CIN overnight
and a veered low level jet, am a little suspicious of the NAM and
especially the GFS which has not had a handle on the low level
moisture now since it began to advect north. Therefore will keep
the forecast VFR overnight. Think deteriorating conditions with
precip is most likely with the eventual FROPA which looks to
affect the terminals early Sunday afternoon.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...Barjenbruch
LONG TERM...Hennecke
AVIATION...Wolters
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
250 AM EDT SAT APR 12 2014
.UPDATE...
ISSUED AT 219 AM EDT SAT APR 12 2014
HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATION AND
SATELLITE AND RADAR TRENDS. AT THIS POINT...OPTED TO HOLD ONTO SLIGHT
CHANCE POPS OVERNIGHT WITH THE STALLED OUT BOUNDARY IN THE VICINITY.
PATCHY VALLEY STILL LOOKS ON TARGET FOR THE EASTERN VALLEYS THAT HAVE
DECOUPLED. THE NORMALLY COLDEST LOCATIONS WERE RUNNING SLIGHTLY
COLDER THAN THE FORECAST...SO MIN T WAS LOWERED FOR THESE LOCATIONS.
OVERALL...NO SIGNIFICANT CHANGES WERE REQUIRED AT THIS POINT.
UPDATE ISSUED AT 1200 AM EDT SAT APR 12 2014
SHORT UPDATE TO REMOVE MENTION OF THUNDER. ISOLATED SHOWERS ARE STILL
SHOWING UP ON THE RADAR MOSAIC...SLIGHT CHANCE POPS STILL LOOKS TO BE
THE WAY TO GO THROUGH THE REMAINDER OF THE OVERNIGHT. COOLEST VALLEY
LOCATIONS WILL SEE SOME PATCHY FOG DEVELOP...ESPECIALLY WHERE ANY
SUBSTANTIAL RAINFALL FELL EARLIER THIS EVENING. FOG COULD BECOME
LOCALLY DENSE IN A FEW ISOLATED LOCATIONS WHERE TEMPERATURES MANAGE
TO DROP INTO THE UPPER 40S.
UPDATE ISSUED AT 1112 PM EDT FRI APR 11 2014
SHOWER AND THUNDERSTORM ACTIVITY IS FINALLY WINDING DOWN...WAITING
FOR CLUSTER OF SHOWERS AND THUNDERSTORMS TO MOVE OUT OF THE AREA
WHICH SHOULD BE WELL BEFORE MIDNIGHT. THEREAFTER EXPECT THE POTENTIAL
FOR AN ISOLD POP UP SHOWER JUST ABOUT ANYWHERE WITH FRONTAL BOUNDARY
IN THE VICINITY. HRRR CONTINUE TO ADVERTISE THE POTENTIAL OF
ADDITIONAL POP UP SHOWERS THROUGH THE REMAINDER OF THE OVERNIGHT
PERIOD...SO WILL MAINTAIN CURRENT SLIGHT POP...ESPECIALLY IN THE
NORTH CLOSER TO THE BOUNDARY. TWEAKED OVERNIGHT LOWS A BIT BASED ON
LATEST TEMP TRENDS. ALSO WITH THE LIGHT RAIN ACROSS PORTIONS OF THE
AREA AND AT LEAST SOME PARTIAL CLEARING INTRODUCED SOME PATCHY FOG
IN OUR COOLEST AREAS/LOCATIONS.
UPDATE ISSUED AT 827 PM EDT FRI APR 11 2014
NORTHERN PORTION OF COMPLEX OF STORMS MOVING THROUGH TN THIS EVENING
WILL CLIP OUR SOUTHERN COUNTIES ALONG THE KY/TN STATE LINE OVER THE
NEXT COUPLE OF HOURS. OTHERWISE ACTIVITY IS SLOWLY MOVING OUT OF THE
AREA AND DIEING OFF. HRRR HAS BEEN DOING DECENT WITH THE SHOWER
ACTIVITY THUS FAR THROUGH THE EVENING. IT CURRENTLY HINTS AT SOME
REDEVELOPMENT THROUGH THE OVERNIGHT PERIOD AND MOVES ACTIVITY
NORTHWARD...IN LINE WITH THE SURFACE BOUNDARY THAT SHOULD ALSO BEGIN
ITS RETREAT NORTHWARD. CONSIDERING THIS AND WITH THE FRONTAL
BOUNDARY IN THE AREA WENT AHEAD AND KEPT A SLIGHT POP THROUGH THE
REMAINDER OF THE NIGHT. OTHERWISE BROUGHT HOURLY GRIDS IN LINE WITH
OBS. OVERNIGHT LOWS LOOK PRETTY GOOD ATTM...BUT CURRENTLY RUNNING
SLIGHTLY WARMER THAN EXPECTED.
UPDATE ISSUED AT 548 PM EDT FRI APR 11 2014
QUICK UPDATE FOR SUDDEN UPTICK IN SHOWER ACTIVITY. ALSO SEEING SOME
CLOUD TO CLOUD...CLOUD TO GROUND LIGHTNING. SO ISOLATED THUNDER LOOKS
TO BE A GOOD BET. UPDATED FORECAST PACKAGE FOR LATEST TRENDS.
AM CONCERNED ABOUT CONVECTION OUT TO OUR WEST CURRENTLY MOVING
THROUGH WESTERN KY THAT APPEARS TO BE RELATED TO SOME SIGNIFICANT
UPPER LEVEL SHORTWAVE ENERGY MOVING ACROSS THE REGION THIS EVENING.
SHORT TERM HIGH RES MODELS TAKE THE BULK OF SHOWER ACTIVITY TO OUR
SOUTHEAST...BUT ALSO GENERATE ADDITION SHOWERS AND THUNDERSTORMS TO
OUR NORTHWEST. FOR NOW AM NOT BUYING INTO NEW CONVECTION TO OUR
NORTHWEST WITH CURRENT FOCUS FURTHER SOUTH WITH THE SURFACE FRONTAL
BOUNDARY...WHICH APPEARS TO BE SAGGING SOUTHWARD SLIGHTLY. BUT
CONVECTION TO THE WEST IS MAKING A BEE LINE STRAIGHT EASTWARD TOWARDS
OUR SOUTHERN MOST ZONES. WILL BE LOOKING OVER TRENDS A BIT MORE
CAREFULLY. SUSPECT ANOTHER UPDATE WILL BE IN THE MAKING WITHIN
ANOTHER HOUR OR SO.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 348 PM EDT FRI APR 11 2014
A WEAK SURFACE COLD FRONT IS ALIGNED NEAR THE OHIO RIVER...WITH A
BROKEN LINE OF SHOWERS AND EMBEDDED THUNDERSTORMS BREAKING OUT WELL
AHEAD OF THE BOUNDARY IN RESPONSE TO A GOOD 850 MB LOW LEVEL JET
EARLIER TODAY. THIS LINE HAS DIMINISHED QUITE A BIT AS IT HAS SAGGED
SOUTHEAST ACROSS PORTIONS OF EASTERN KENTUCKY...WITH ONLY SOME
ISOLATED TO SCATTERED SHOWERS LEFT OF IT AT THIS POINT. MEANWHILE...A
SHORT WAVE TROUGH WAS MOVING ESE ACROSS MISSOURI...WITH CONVECTION
STARTING TO BLOSSOM JUST NORTHWEST OF THE BOOTHEEL.
EXPECT A SMALL THREAT OF CONVECTION GENERALLY ALONG AND SOUTH OF THE
MOUNTAIN PARKWAY TO CONTINUE THROUGH THIS EVENING. SHOWERS AND STORMS
ASSOCIATED WITH THE MISSOURI SHORT WAVE MAY POSSIBLY BRUSH OUR FAR
SOUTHWEST EARLY THIS EVENING...ALTHOUGH THE HRRR RUNS HAVE BEEN
TRENDING A BIT FURTHER SOUTHWEST WITH THE PATH...CLOSER TO THE
BETTER INSTABILITY. LOWS TONIGHT WILL BOTTOM OUT IN THE LOW TO MID
50S UNDER PARTLY CLOUDY TO MOSTLY CLOUDY SKIES.
THE LEFTOVER FRONTAL BOUNDARY WILL ATTEMPT TO PUSH SOUTHEAST ACROSS
OUR AREA TONIGHT. THE NAM STALLS THIS BOUNDARY FURTHER NORTH...AND
LOOKING UPSTREAM AT THE WEAK PUSH BEHIND IT...THIS SEEMS REASONABLE.
AS SUCH...HAVE LIMITED A SMALL RESURGENCE OF THE POPS ASSOCIATED
WITH SOME WEAK ISENTROPIC LIFT FURTHER NORTH AND EAST INTO THE DAY ON
SATURDAY. THE BOUNDARY WILL THEN RETREAT NORTHWARD IN THE
AFTERNOON...WITH HIGHS PUSHING 80 DEGREES AT SOME LOCATIONS AS CLOUDS
THIN OUT.
SATURDAY NIGHT WILL FEATURE A MILD NIGHT WITH RIDGE/VALLEY
DIFFERENCES. COOLER SPOTS WILL LIKELY DIP INTO THE 40S...WHILE THE
RIDGETOPS STAY IN THE MID AND UPPER 50S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 348 PM EDT FRI APR 11 2014
OVERALL...THE MODELS WERE IN DECENT AGREEMENT REGARDING THE LARGE
SCALE WEATHER PATTERN AND SENSIBLE WEATHER FOR THE EXTENDED PERIOD.
THE BIG PICTURE SHOWN IN THE MODELS DEPICTS A LARGE TROUGH OF LOW
PRESSURE...AND ITS WELL DEFINED TRAILING COLD FRONT...MOVING ACROSS
SOUTHERN CANADA AND THE OHIO AND TENNESSEE VALLEYS RESPECTIVELY
SUNDAY NIGHT THROUGH TUESDAY NIGHT. ONCE THAT SYSTEM IS THROUGH THE
AREA...IT APPEARS THAT A LARGE RIDGE OF HIGH PRESSURE WILL SETTLE
OVER THE AREA...BRINGING A RETURN TO WARM AND DRY WEATHER TO END TO
UPCOMING WORKWEEK. THE PERIOD LOOKS TO START OFF WARM AND DRY...AS A
VERY STRONG RIDGE OF HIGH PRESSURE REMAINS IN PLACE ACROSS THE AREA
SUNDAY AND MONDAY. IN FACT...HIGH TEMPERATURES ON SUNDAY COULD REACH
THE 80S ACROSS MOST OF THE AREA...WITH MAX TEMPS ON MONDAY CLIMBING
INTO THE 70S ACROSS THE BOARD. CONSIDERING THE ANTICIPATED STRENGTH
OF THE RIDGE SUNDAY AND MONDAY...DECIDED TO ADJUST TEMPERATURES MORE
TOWARD THE WARMER MEXMOS GUIDANCE...AS THOSE NUMBER SEEMED MORE
REASONABLE CONSIDERING THE ANTICIPATED CONDITIONS. DUE TO THE TIMING
OF THE FRONTAL PASSAGE TUESDAY AND TUESDAY NIGHT...WINDS ARE
EXPECTED TO SHIFT TO THE WEST OR NORTHWEST DURING THE DAY...WHICH
WOULD LEAD TO A NON DIURNAL TEMPERATURE DROP BEHIND THE FRONT. THIS
WAS ONCE AGAIN REFLECTED IN THE FORECAST GRIDS. AS COLDER AIR SPILLS
INTO THE REGION TUESDAY NIGHT...THERE MAY BE A BRIEF PERIOD OF TIME
WHERE A FEW SNOW SHOWERS COULD MIX WITH LINGERING RAIN SHOWERS
ACROSS OUR FAR EAST. AS CLOUDS CLEAR OFF AND WINDS DIE DOWN TUESDAY
NIGHT...TEMPERATURES ARE FORECAST TO DROP TO AROUND 30 BY EARLY
WEDNESDAY MORNING. THESE CONDITIONS MAY ALLOW SOME PATCHY VALLEY
FROST TO FORM...PARTICULARLY IN THE DEEPER AND MORE SHELTERED
VALLEYS. THE SLIGHTLY COOLER ECMWF EXTENDED MOS GUIDANCE WAS
PREFERRED HERE...ACCOUNTING FOR THE CLEAR AND CALM CONDITIONS
TUESDAY NIGHT. A KILLING FREEZE MIGHT EVEN OCCUR IF THE VALLEYS ARE
ABLE TO DROP INTO THE UPPER 20S AREA WIDE. IT WILL BEAR WATCHING TO
BE SURE.
THE CONSENSUS AMONGST THE MODELS IS FOR A LARGE SWATH OF SHOWERS AND
STORMS TO DEVELOP ALONG AND OUT AHEAD OF THE ADVANCING FRONT MONDAY
AND TUESDAY. THE LATEST MODEL SOUNDINGS ARE SUGGESTING ONLY MEAGER
INSTABILITY ACCOMPANYING THE FRONT...SO ANY THUNDERSTORMS THAT FORM
WILL BE ISOLATED IN NATURE. THE MODEL SOUNDINGS ARE SHOWING A VERY
DEEP LAYER OF MOISTURE MOVING ACROSS THE AREA WITH THE FRONT...WHICH
WOULD CREATE THE POTENTIAL FOR LOCALLY HEAVY RAIN WITH ANY STORMS OR
INTENSE SHOWERS THAT MOVE ACROSS THE AREA. THIS WAS REFLECTED IN THE
NEW RAINFALL AMOUNT FORECAST. THE MODEL PLAN VIEWS WERE ALSO
SUGGESTIVE OF THIS...WITH THE ECMWF BEING SLIGHTLY WETTER THAN THE
GFS. WITH THE SYSTEM MOVING ACROSS THE AREA FAIRLY QUICKLY...DECIDED
TO COMPROMISE BETWEEN THE TWO MODELS...GOING WITH 6 HOUR RAINFALL
TOTALS SLIGHTLY HIGHER THAN THE GFS...AND SLIGHTLY LOWER THAN THE
ECMWF DATA. DUE TO THE STRENGTH OF THE SYSTEM...WINDS ON MONDAY AND
TUESDAY COULD BE FAIRLY STRONG...WITH SUSTAINED WINDS OF 10 TO 15
MPH WITH HIGHER GUSTS ON BOTH DAYS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 215 AM EDT SAT APR 12 2014
WITH RAIN SHOWERS MOVING THROUGH THE AREA THIS EVENING AND AT LEAST
SOME PARTIAL CLEARING EXPECTED LATE TONIGHT FELT SOME LIGHT FOG
POTENTIAL EXISTS. OF THE TAF SITES...LOZ HAD THE MOST RAINFALL SO
HAVE OPTED FOR MVFR FOG THERE. OTHERWISE...VIS UNDER 6SM IS NOT
EXPECTED. OTHERWISE VFR CONDITIONS EXPECTED AS ANY ISOLATED SHRA OR
TSRA BETWEEN 6Z AND 18Z SHOULD OCCUR NORTH OF THE TAF SITES. WINDS
WILL BE LIGHT...BUT INCREASE FROM THE SOUTH...SOUTHWEST AT AROUND 10
KT SAT AND POSSIBLY REMAIN NEAR THESE LEVELS INTO THE LAST 6 HOURS OF
THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...GEOGERIAN
LONG TERM...AR
AVIATION...JP
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
114 PM EDT SAT APR 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 516 AM EDT SAT APR 12 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A SHORTWAVE TROUGH OVER NORTH
DAKOTA IN ZONAL MID/UPPER LEVEL FLOW ACROSS THE NRN CONUS. AT THE
SFC...LOW PRES WAS LOCATED OVER SE SD WITH A WARM FRONT INTO NRN IA.
FARTHER NORTH...A COLD FRONT EXTENDED FROM CNTRL LAKE SUPERIOR
INTO NE SD BORDERING ARCTIC HIGH PRES BUILDING THROUGH NRN OTARIO.
SHRA FROM CNTRL MN AND NW WI INTO SW MN AND NRN IA WAS SUPPORTED BY
STRONG 295K-300K ISENTROPIC LIFT AHEAD OF THE WARM FRONT. THERE WAS
ALSO ENOUGH CONVECTIVE INSTABILITY TO SUPPORT ISOLD TSRA FROM ERN SD
INTO NW IA.
TODAY...RADAR/SATELLITE TRENDS AND MODELS SUGGEST THAT THE AREA OF
PCPN WILL CONTINUE TO EXPAND TO THE ENE INTO UPPER MI AS THE BAND OF
ISENTROPIC LIFT MOVES THROUGH AIDED BY UPPER LEVEL DIV ASSOCIATED
WITH THE RIGHT ENTRANCE OF THE 250-300 JET LIFTING INTO NRN ONTARIO
MOVES THROUGH. THE HEAVIEST PCPN IS EXPECTED MAINLY ACROSS THE SRN
HALF OF THE CWA...CLOSEST TO THE 850-700 TEMP GRADIENT...WITH
OVERALL QPF VALUES IN THE 0.30 TO 0.60 INCH RANGE. FCST MUCAPE
VALUES TO AROUND 400 J/KG ALSO SUPPORT THE POTENTIAL FOR TSRA OVER
THE SOUTH THIS AFTERNOON AND EVENING.
THE MAIN FCST QUESTIONS WILL BE PCPN TYPE AND SNOWFALL AMOUNTS. THE
NAM AND REGIONAL GEM LOW LEVEL THICKNESS AND WET-BULB ZERO HEIGHTS
SUGGEST THAT LOW LEVEL TEMPS WILL BE LOW ENOUGH AIDED BY EVAPORATIVE
COOLING FOR A PERIOD OF SNOW OVER THE NW HALF OF UPPER MI LATE THIS
MORNING INTO EARLY AFTERNOON THAT WOULD GRADUALLY CHANGE OVER TO
RAIN OR DRIZZLE AS WARMER AIR IN THE 900-750 MB LAYER MOVES IN ALONG
WITH MID LEVEL DRYING. THE PCPN INTENSITY MAY BE HIGH ENOUGH SO THAT
A COUPLE INCHES OF WET SNOW MAY ACCUMULATE EVEN WITH AIR TEMPS INTO
THE MID 30S. FORTUNATELY...THE AIR AND GROUND TEMPS SHOULD REMAIN
HIGH ENOUGH TO LIMIT ANY POTENTIAL FOR FREEZING PCPN AS THE SNOW
CHANGES OVER TO RAIN.
TONIGHT...THE PCPN WILL TAPER OFF FROM WEST TO EAST IN THE EVENING AS THE
SUPPORTING DYNAMICS EXIT THE AREA. HOWEVER...THERE MAY STILL BE SOME
LINGERING LIGHT RAIN OR DRIZZLE...ESPECIALLY IN LOCATIONS FAVORED BY
UPSLOP ERLY FLOW.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 505 AM EDT SAT APR 12 2014
UNSEASONABLY COOL AIR WILL BE TRAPPED ACROSS UPPER MI THROUGH AT
LEAST THE MIDDLE OF THE NEXT WORK WEEK. THE MODEL SPREAD IS ROUGHLY
10F FROM TUESDAY THROUGH FRIDAY FOR MAX TEMPS...WITH OUR OFFICIAL
FCST BOUNCING FROM ALL ALONG THE SPECTRUM
THE WEATHER MAP AT 12Z SUNDAY WILL SHOW A HIGH AMPLITUDE 500MB RIDGE
ACROSS THE W COAST...AND THE SE U.S. IN THE MIDDLE A TROUGH WILL
EXTEND FROM HUDSON BAY THROUGH S CENTRAL CANADA AND THROUGH WY AND
CO. THE 500MB LOW WILL CONTINUE TO BE REINFORCED OVER HUDSON BAY
SUNDAY NIGHT...AND DIG ACROSS FAR N ONTARIO MONDAY THROUGH TUESDAY.
THIS WILL RESULT IN A RETURN OF MUCH COOLER THAN NORMAL
TEMPERATURES. NORMAL HIGH TEMPERATURES OVER MUCH OF THE CWA ARE NOW
IN THE MID 40S.
LOW PRESSURE STRETCHING FROM OK THROUGH NE AND LOWER MI AT 12Z
SUNDAY WILL SLOWLY PUSH TO LOWER MI AND FAR S QUEBEC BY 12Z
MONDAY...AND DEEPEN AS IT MOVES OVER FAR E CANADA MONDAY NIGHT.
ACROSS THE UPPER GREAT LAKES...PLENTY OF COLD AIR WILL FILTER IN
BEHIND THE LOW. NW WIND GUSTS MONDAY AFTERNOON MAY TOP OUT 20 TO
NEAR 30KTS...STRONGEST ACROSS THE KEWEENAW PENINSULA AND E ALONG THE
LAKE SUPERIOR SHORELINE.
THE COLDEST DAY /TUESDAY/ WILL SEE TEMPS STRUGGLING TO GET TO THE
FREEZING MARK DURING THE DAYTIME HOURS AS COLD HIGH PRESSURE SETTLES
IN AT THE SFC...WITH NW FLOW REMAINING ALOFT. THE COLD TEMPERATURES
WILL HAVE A SIGNIFICANT IMPACT ON SNOWMELT AND RIVER LEVELS THROUGH
AT LEAST THE FIRST HALF OF THE WORK WEEK...SLOWING DOWN THE WHOLE
PROCESS. LOOK FOR 850MB TEMPS TO FALL BELOW -8C OVER THE W HALF BY
12Z WEDNESDAY...CHANGING ANY LINGERING LIGHT PRECIP TO ALL SNOW/SNOW
SHOWERS.
THE LATTER HALF OF THE WORK WEEK WILL BE MORE JUMBLED...WITH THE A
GENERAL 500MB TROUGH OVER S CENTRAL CANADA AND THE N PLAINS STATES
WEDNESDAY NIGHT. THE NAM LOOKS TO BE MUCH DEEPER WITH THE S EXTENDED
OF THE LOW FOR TH-FRI. WILL CONTINUE TO GO MIDDLE OF THE ROAD FOR
THIS LONGER TERM PERIOD. THE MID WEEK SFC HIGH WILL BE REPLACED BY
YET ANOTHER INVERTED TROUGH SETTING UP FROM THE S PLAINS THROUGH NM
AND WI AT 00Z THURSDAY. THE LATEST ECMWF HAS THE SFC LOW TRACKING
ACROSS UPPER MI THURSDAY AFTERNOON WHILE THE GFS DOESN/T HAVE IT
CROSSING UPPER MI UNTIL FRIDAY NIGHT/SATURDAY MORNING. WILL NOT JUMP
INTO THE WEEDS OF THE EXTENDED FCST AT THIS POINT DUE TO THE
UNCERTAINTY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 114 PM EDT SAT APR 12 2014
CONDITIONS WILL CONTINUE TO SLOWLY DETERIORATE THIS AFTERNOON WITH
FOG AND LOW CLOUDS MOVING IN AND SHOULD GO TO IFR/LIFR AT ALL SITES.
THIS WILL LAST THROUGH THE REST OF THE FORECAST PERIOD AS LOW LEVEL
MOISTURE REMAINS TRAPPED AND THERE WILL ALSO BE SOME UPSLOPE
COMPONENT TO THE WIND AS WELL TO KEEP DRIZZLE AND FOG IN THE AREA.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 516 AM EDT SAT APR 12 2014
EAST WINDS WILL INCREASE TO 25 KNOTS OVER THE WRN HALF OF THE LAKE
TODAY AS THE PRES GRADIENT TIGHTENS BTWN HIGH PRES BUILDING FROM NRN
ONTARIO INTO QUEBEC AND A LOW INTO IA. WINDS ARE ALSO EXPECTED TO
INCREASE TO 30 KNOTS MONDAY OVER CNTRL AND ERN LAKE SUPERIOR BETWEEN
HIGH RPESSURE OVER THE PLAINS AND A LOW PRES SYSTE OVER THE ERN
GREAT LAKES.
&&
.HYDROLOGY...
ISSUED AT 417 AM EDT SAT APR 12 2014
FORTUNATELY...LIMITED RAINFALL AND TEMPERATURES NEAR OR SLIGHTLY
ABOVE NORMAL HAS KEPT THE SNOWMELT SIMILAR TO NORMAL SPRING
CONDITIONS. WOULD EXPECT A SLOW STEADY RISE IN RIVER LEVELS
TODAY...WITHOUT ANY LARGER RIVERS RISING ABOVE BANKFULL AT THIS TIME.
THE PROBLEM AREAS SO FAR HAVE BEEN SMALL CREEKS AND STREAMS IN DELTA
COUNTY WHERE HAVE BEEN NEAR OR OUT OF THEIR BANKS OVER THE PAST
COUPLE OF DAYS. HOWEVER...NO SIGNIFICANT IMPACTS WERE NOTED. THERE
HAS SEEN EVIDENCE OF MINOR ICE JAMES ON SOME HYDROGRAPHS OVER THE
LAST DAY OR SO...MOST NOTABLY ON THE ONTONAGON RIVER NEAR ROCKLAND
(RKLM4) AND THE FORD RIVER NEAR HYDE (FRDM4). THE RKLM4 ICE JAM SEEMS
TO HAVE MOVED DOWNSTREAM OR BROKEN UP...BUT DO NOT KNOW ABOUT THE
STATE OF THE RIVER DOWNSTREAM GIVEN A LACK OF REPORTS/RIVER ACCESS.
THE FRDM4 ICE JAM LOOKS TO HAVE RELAXED FRIDAY EVENING. CURRENTLY
HAVE ISSUED A STATEMENT FOR THAT RIVER TO WARN OF FLUCTUATING RIVER
LEVELS AND ICE IS LIKELY STILL IN THE SYSTEM. AM UNSURE OF
IMPACTS/EXTENT OF THIS ICE JAM AS RIVER BANKS/STRUCTURES ARE FAIRLY
HIGH ABOVE THE RIVER PER DISCUSSION WITH LOCAL OFFICIALS. THERE WERE
ALSO REPORTS OF MINOR ICE JAMS ON OTHER AREA CREEKS/STREAMS THAT ARE
NOT GAUGED...BUT NO IMPACTS WERE NOTED. THIS ICE BREAK UP DOES LEAD
TO SOME CONCERN FOR ICE JAMS ON OTHER RIVERS ACROSS THE
CWA...ESPECIALLY FOR RIVERS THAT EMPTY INTO THE MAINLY FROZEN GREAT
LAKES.
A LOW PRESSURE TROUGH MOVING THROUGH THE UPPER GREAT LAKES REGION
TODAY WILL LEAD TO PERIODS OF RAIN AND SNOW /MELTING AS IT FALLS/
THROUGH SATURDAY EVENING. THE CURRENT FORECAST CALLS FOR AMOUNTS TO
BE IN THE 0.30-0.50 INCH RANGE...BUT WITH COOLER TEMPERATURES
ARRIVING WITH THIS RAIN...THE IMPACT ON THE RIVERS SHOULD BE
LIMITED. EXPECT COLDER AIR TO SURGE IN SUNDAY NIGHT THROUGH THE
FIRST HALF OF THE WORK WEEK. THIS WILL SIGNIFICANTLY REDUCE OR EVEN
END THE SNOW MELT...AS HIGHS WILL ONLY BE IN THE 30S AND LOWS WILL
BE WELL BELOW FREEZING. SINCE 4-9 INCHES OF SNOW WATER EQUIVALENT
STILL REMAINS OVER PARTS OF WESTERN AND CENTRAL UPPER
MICHIGAN...THERE IS STILL PLENTY OF WATER AVAILABLE FOR THE SECOND
PERIOD OF SNOW MELT OVER THE NEXT COUPLE OF WEEKS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...07
MARINE...JLB
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
822 AM EDT SAT APR 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 516 AM EDT SAT APR 12 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A SHORTWAVE TROUGH OVER NORTH
DAKOTA IN ZONAL MID/UPPER LEVEL FLOW ACROSS THE NRN CONUS. AT THE
SFC...LOW PRES WAS LOCATED OVER SE SD WITH A WARM FRONT INTO NRN IA.
FARTHER NORTH...A COLD FRONT EXTENDED FROM CNTRL LAKE SUPERIOR
INTO NE SD BORDERING ARCTIC HIGH PRES BUILDING THROUGH NRN OTARIO.
SHRA FROM CNTRL MN AND NW WI INTO SW MN AND NRN IA WAS SUPPORTED BY
STRONG 295K-300K ISENTROPIC LIFT AHEAD OF THE WARM FRONT. THERE WAS
ALSO ENOUGH CONVECTIVE INSTABILITY TO SUPPORT ISOLD TSRA FROM ERN SD
INTO NW IA.
TODAY...RADAR/SATELLITE TRENDS AND MODELS SUGGEST THAT THE AREA OF
PCPN WILL CONTINUE TO EXPAND TO THE ENE INTO UPPER MI AS THE BAND OF
ISENTROPIC LIFT MOVES THROUGH AIDED BY UPPER LEVEL DIV ASSOCIATED
WITH THE RIGHT ENTRANCE OF THE 250-300 JET LIFTING INTO NRN ONTARIO
MOVES THROUGH. THE HEAVIEST PCPN IS EXPECTED MAINLY ACROSS THE SRN
HALF OF THE CWA...CLOSEST TO THE 850-700 TEMP GRADIENT...WITH
OVERALL QPF VALUES IN THE 0.30 TO 0.60 INCH RANGE. FCST MUCAPE
VALUES TO AROUND 400 J/KG ALSO SUPPORT THE POTENTIAL FOR TSRA OVER
THE SOUTH THIS AFTERNOON AND EVENING.
THE MAIN FCST QUESTIONS WILL BE PCPN TYPE AND SNOWFALL AMOUNTS. THE
NAM AND REGIONAL GEM LOW LEVEL THICKNESS AND WET-BULB ZERO HEIGHTS
SUGGEST THAT LOW LEVEL TEMPS WILL BE LOW ENOUGH AIDED BY EVAPORATIVE
COOLING FOR A PERIOD OF SNOW OVER THE NW HALF OF UPPER MI LATE THIS
MORNING INTO EARLY AFTERNOON THAT WOULD GRADUALLY CHANGE OVER TO
RAIN OR DRIZZLE AS WARMER AIR IN THE 900-750 MB LAYER MOVES IN ALONG
WITH MID LEVEL DRYING. THE PCPN INTENSITY MAY BE HIGH ENOUGH SO THAT
A COUPLE INCHES OF WET SNOW MAY ACCUMULATE EVEN WITH AIR TEMPS INTO
THE MID 30S. FORTUNATELY...THE AIR AND GROUND TEMPS SHOULD REMAIN
HIGH ENOUGH TO LIMIT ANY POTENTIAL FOR FREEZING PCPN AS THE SNOW
CHANGES OVER TO RAIN.
TONIGHT...THE PCPN WILL TAPER OFF FROM WEST TO EAST IN THE EVENING AS THE
SUPPORTING DYNAMICS EXIT THE AREA. HOWEVER...THERE MAY STILL BE SOME
LINGERING LIGHT RAIN OR DRIZZLE...ESPECIALLY IN LOCATIONS FAVORED BY
UPSLOP ERLY FLOW.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 505 AM EDT SAT APR 12 2014
UNSEASONABLY COOL AIR WILL BE TRAPPED ACROSS UPPER MI THROUGH AT
LEAST THE MIDDLE OF THE NEXT WORK WEEK. THE MODEL SPREAD IS ROUGHLY
10F FROM TUESDAY THROUGH FRIDAY FOR MAX TEMPS...WITH OUR OFFICIAL
FCST BOUNCING FROM ALL ALONG THE SPECTRUM
THE WEATHER MAP AT 12Z SUNDAY WILL SHOW A HIGH AMPLITUDE 500MB RIDGE
ACROSS THE W COAST...AND THE SE U.S. IN THE MIDDLE A TROUGH WILL
EXTEND FROM HUDSON BAY THROUGH S CENTRAL CANADA AND THROUGH WY AND
CO. THE 500MB LOW WILL CONTINUE TO BE REINFORCED OVER HUDSON BAY
SUNDAY NIGHT...AND DIG ACROSS FAR N ONTARIO MONDAY THROUGH TUESDAY.
THIS WILL RESULT IN A RETURN OF MUCH COOLER THAN NORMAL
TEMPERATURES. NORMAL HIGH TEMPERATURES OVER MUCH OF THE CWA ARE NOW
IN THE MID 40S.
LOW PRESSURE STRETCHING FROM OK THROUGH NE AND LOWER MI AT 12Z
SUNDAY WILL SLOWLY PUSH TO LOWER MI AND FAR S QUEBEC BY 12Z
MONDAY...AND DEEPEN AS IT MOVES OVER FAR E CANADA MONDAY NIGHT.
ACROSS THE UPPER GREAT LAKES...PLENTY OF COLD AIR WILL FILTER IN
BEHIND THE LOW. NW WIND GUSTS MONDAY AFTERNOON MAY TOP OUT 20 TO
NEAR 30KTS...STRONGEST ACROSS THE KEWEENAW PENINSULA AND E ALONG THE
LAKE SUPERIOR SHORELINE.
THE COLDEST DAY /TUESDAY/ WILL SEE TEMPS STRUGGLING TO GET TO THE
FREEZING MARK DURING THE DAYTIME HOURS AS COLD HIGH PRESSURE SETTLES
IN AT THE SFC...WITH NW FLOW REMAINING ALOFT. THE COLD TEMPERATURES
WILL HAVE A SIGNIFICANT IMPACT ON SNOWMELT AND RIVER LEVELS THROUGH
AT LEAST THE FIRST HALF OF THE WORK WEEK...SLOWING DOWN THE WHOLE
PROCESS. LOOK FOR 850MB TEMPS TO FALL BELOW -8C OVER THE W HALF BY
12Z WEDNESDAY...CHANGING ANY LINGERING LIGHT PRECIP TO ALL SNOW/SNOW
SHOWERS.
THE LATTER HALF OF THE WORK WEEK WILL BE MORE JUMBLED...WITH THE A
GENERAL 500MB TROUGH OVER S CENTRAL CANADA AND THE N PLAINS STATES
WEDNESDAY NIGHT. THE NAM LOOKS TO BE MUCH DEEPER WITH THE S EXTENDED
OF THE LOW FOR TH-FRI. WILL CONTINUE TO GO MIDDLE OF THE ROAD FOR
THIS LONGER TERM PERIOD. THE MID WEEK SFC HIGH WILL BE REPLACED BY
YET ANOTHER INVERTED TROUGH SETTING UP FROM THE S PLAINS THROUGH NM
AND WI AT 00Z THURSDAY. THE LATEST ECMWF HAS THE SFC LOW TRACKING
ACROSS UPPER MI THURSDAY AFTERNOON WHILE THE GFS DOESN/T HAVE IT
CROSSING UPPER MI UNTIL FRIDAY NIGHT/SATURDAY MORNING. WILL NOT JUMP
INTO THE WEEDS OF THE EXTENDED FCST AT THIS POINT DUE TO THE
UNCERTAINTY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 822 AM EDT SAT APR 12 2014
ALTHOUGH MID/HI CLDS WILL BE THICKENING EARLY TODAY...EXPECT
PREDOMINANT VFR CONDITIONS AND LIGHT WINDS WITH A WEAK RIDGE AND LOW
LEVEL DRY AIR IN PLACE. BUT AS A LOW TAKING SHAPE IN THE NORTHERN
PLAINS MOVES INTO THE UPPER MIDWEST THIS AFTERNOON...WIDESPREAD
PCPN WILL DEVELOP FROM WEST TO EAST OVER UPPER MI WITH THE ARRIVAL
OF DEEPER MOISTURE AND DYNAMIC SUPPORT. WHERE THE AIRMASS IS COLD
ENOUGH FOR MAINLY SNOW AND THE LOW LEVEL ESE WIND WILL UPSLOPE AT
CMX AND SAW...EXPECT LIFR CONDITIONS FROM LATE THIS MORNING THROUGH
MUCH OF THE AFTERNOON. BUT EVEN AT IWD WHERE THE PCPN WILL BE
LIGHTER AND MIXED WITH RAIN...IFR CIGS ARE FCST. ALTHOUGH THE STEADY
PCPN WILL END BY 00Z SUN... LINGERING MOIST E WINDS AND SHALLOW COLD
AIR WL RESULT IN LINGERING LOW CLDS/FOG/SOME -DZ/FZDZ...ESPECIALLY
AT CMX AND SAW WHERE THE FLOW WILL UPSLOPE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 516 AM EDT SAT APR 12 2014
EAST WINDS WILL INCREASE TO 25 KNOTS OVER THE WRN HALF OF THE LAKE
TODAY AS THE PRES GRADIENT TIGHTENS BTWN HIGH PRES BUILDING FROM NRN
ONTARIO INTO QUEBEC AND A LOW INTO IA. WINDS ARE ALSO EXPECTED TO
INCREASE TO 30 KNOTS MONDAY OVER CNTRL AND ERN LAKE SUPERIOR BETWEEN
HIGH RPESSURE OVER THE PLAINS AND A LOW PRES SYSTE OVER THE ERN
GREAT LAKES.
&&
.HYDROLOGY...
ISSUED AT 417 AM EDT SAT APR 12 2014
FORTUNATELY...LIMITED RAINFALL AND TEMPERATURES NEAR OR SLIGHTLY
ABOVE NORMAL HAS KEPT THE SNOWMELT SIMILAR TO NORMAL SPRING
CONDITIONS. WOULD EXPECT A SLOW STEADY RISE IN RIVER LEVELS
TODAY...WITHOUT ANY LARGER RIVERS RISING ABOVE BANKFULL AT THIS TIME.
THE PROBLEM AREAS SO FAR HAVE BEEN SMALL CREEKS AND STREAMS IN DELTA
COUNTY WHERE HAVE BEEN NEAR OR OUT OF THEIR BANKS OVER THE PAST
COUPLE OF DAYS. HOWEVER...NO SIGNIFICANT IMPACTS WERE NOTED. THERE
HAS SEEN EVIDENCE OF MINOR ICE JAMES ON SOME HYDROGRAPHS OVER THE
LAST DAY OR SO...MOST NOTABLY ON THE ONTONAGON RIVER NEAR ROCKLAND
(RKLM4) AND THE FORD RIVER NEAR HYDE (FRDM4). THE RKLM4 ICE JAM SEEMS
TO HAVE MOVED DOWNSTREAM OR BROKEN UP...BUT DO NOT KNOW ABOUT THE
STATE OF THE RIVER DOWNSTREAM GIVEN A LACK OF REPORTS/RIVER ACCESS.
THE FRDM4 ICE JAM LOOKS TO HAVE RELAXED FRIDAY EVENING. CURRENTLY
HAVE ISSUED A STATEMENT FOR THAT RIVER TO WARN OF FLUCTUATING RIVER
LEVELS AND ICE IS LIKELY STILL IN THE SYSTEM. AM UNSURE OF
IMPACTS/EXTENT OF THIS ICE JAM AS RIVER BANKS/STRUCTURES ARE FAIRLY
HIGH ABOVE THE RIVER PER DISCUSSION WITH LOCAL OFFICIALS. THERE WERE
ALSO REPORTS OF MINOR ICE JAMS ON OTHER AREA CREEKS/STREAMS THAT ARE
NOT GAUGED...BUT NO IMPACTS WERE NOTED. THIS ICE BREAK UP DOES LEAD
TO SOME CONCERN FOR ICE JAMS ON OTHER RIVERS ACROSS THE
CWA...ESPECIALLY FOR RIVERS THAT EMPTY INTO THE MAINLY FROZEN GREAT
LAKES.
A LOW PRESSURE TROUGH MOVING THROUGH THE UPPER GREAT LAKES REGION
TODAY WILL LEAD TO PERIODS OF RAIN AND SNOW /MELTING AS IT FALLS/
THROUGH SATURDAY EVENING. THE CURRENT FORECAST CALLS FOR AMOUNTS TO
BE IN THE 0.30-0.50 INCH RANGE...BUT WITH COOLER TEMPERATURES
ARRIVING WITH THIS RAIN...THE IMPACT ON THE RIVERS SHOULD BE
LIMITED. EXPECT COLDER AIR TO SURGE IN SUNDAY NIGHT THROUGH THE
FIRST HALF OF THE WORK WEEK. THIS WILL SIGNIFICANTLY REDUCE OR EVEN
END THE SNOW MELT...AS HIGHS WILL ONLY BE IN THE 30S AND LOWS WILL
BE WELL BELOW FREEZING. SINCE 4-9 INCHES OF SNOW WATER EQUIVALENT
STILL REMAINS OVER PARTS OF WESTERN AND CENTRAL UPPER
MICHIGAN...THERE IS STILL PLENTY OF WATER AVAILABLE FOR THE SECOND
PERIOD OF SNOW MELT OVER THE NEXT COUPLE OF WEEKS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...JLB
MARINE...JLB
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
516 AM EDT SAT APR 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 516 AM EDT SAT APR 12 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A SHORTWAVE TROUGH OVER NORTH
DAKOTA IN ZONAL MID/UPPER LEVEL FLOW ACROSS THE NRN CONUS. AT THE
SFC...LOW PRES WAS LOCATED OVER SE SD WITH A WARM FRONT INTO NRN IA.
FARTHER NORTH...A COLD FRONT EXTENDED FROM CNTRL LAKE SUPERIOR
INTO NE SD BORDERING ARCTIC HIGH PRES BUILDING THROUGH NRN OTARIO.
SHRA FROM CNTRL MN AND NW WI INTO SW MN AND NRN IA WAS SUPPORTED BY
STRONG 295K-300K ISENTROPIC LIFT AHEAD OF THE WARM FRONT. THERE WAS
ALSO ENOUGH CONVECTIVE INSTABILITY TO SUPPORT ISOLD TSRA FROM ERN SD
INTO NW IA.
TODAY...RADAR/SATELLITE TRENDS AND MODELS SUGGEST THAT THE AREA OF
PCPN WILL CONTINUE TO EXPAND TO THE ENE INTO UPPER MI AS THE BAND OF
ISENTROPIC LIFT MOVES THROUGH AIDED BY UPPER LEVEL DIV ASSOCIATED
WITH THE RIGHT ENTRANCE OF THE 250-300 JET LIFTING INTO NRN ONTARIO
MOVES THROUGH. THE HEAVIEST PCPN IS EXPECTED MAINLY ACROSS THE SRN
HALF OF THE CWA...CLOSEST TO THE 850-700 TEMP GRADIENT...WITH
OVERALL QPF VALUES IN THE 0.30 TO 0.60 INCH RANGE. FCST MUCAPE
VALUES TO AROUND 400 J/KG ALSO SUPPORT THE POTENTIAL FOR TSRA OVER
THE SOUTH THIS AFTERNOON AND EVENING.
THE MAIN FCST QUESTIONS WILL BE PCPN TYPE AND SNOWFALL AMOUNTS. THE
NAM AND REGIONAL GEM LOW LEVEL THICKNESS AND WET-BULB ZERO HEIGHTS
SUGGEST THAT LOW LEVEL TEMPS WILL BE LOW ENOUGH AIDED BY EVAPORATIVE
COOLING FOR A PERIOD OF SNOW OVER THE NW HALF OF UPPER MI LATE THIS
MORNING INTO EARLY AFTERNOON THAT WOULD GRADUALLY CHANGE OVER TO
RAIN OR DRIZZLE AS WARMER AIR IN THE 900-750 MB LAYER MOVES IN ALONG
WITH MID LEVEL DRYING. THE PCPN INTENSITY MAY BE HIGH ENOUGH SO THAT
A COUPLE INCHES OF WET SNOW MAY ACCUMULATE EVEN WITH AIR TEMPS INTO
THE MID 30S. FORTUNATELY...THE AIR AND GROUND TEMPS SHOULD REMAIN
HIGH ENOUGH TO LIMIT ANY POTENTIAL FOR FREEZING PCPN AS THE SNOW
CHANGES OVER TO RAIN.
TONIGHT...THE PCPN WILL TAPER OFF FROM WEST TO EAST IN THE EVENING AS THE
SUPPORTING DYNAMICS EXIT THE AREA. HOWEVER...THERE MAY STILL BE SOME
LINGERING LIGHT RAIN OR DRIZZLE...ESPECIALLY IN LOCATIONS FAVORED BY
UPSLOP ERLY FLOW.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 505 AM EDT SAT APR 12 2014
UNSEASONABLY COOL AIR WILL BE TRAPPED ACROSS UPPER MI THROUGH AT
LEAST THE MIDDLE OF THE NEXT WORK WEEK. THE MODEL SPREAD IS ROUGHLY
10F FROM TUESDAY THROUGH FRIDAY FOR MAX TEMPS...WITH OUR OFFICIAL
FCST BOUNCING FROM ALL ALONG THE SPECTRUM
THE WEATHER MAP AT 12Z SUNDAY WILL SHOW A HIGH AMPLITUDE 500MB RIDGE
ACROSS THE W COAST...AND THE SE U.S. IN THE MIDDLE A TROUGH WILL
EXTEND FROM HUDSON BAY THROUGH S CENTRAL CANADA AND THROUGH WY AND
CO. THE 500MB LOW WILL CONTINUE TO BE REINFORCED OVER HUDSON BAY
SUNDAY NIGHT...AND DIG ACROSS FAR N ONTARIO MONDAY THROUGH TUESDAY.
THIS WILL RESULT IN A RETURN OF MUCH COOLER THAN NORMAL
TEMPERATURES. NORMAL HIGH TEMPERATURES OVER MUCH OF THE CWA ARE NOW
IN THE MID 40S.
LOW PRESSURE STRETCHING FROM OK THROUGH NE AND LOWER MI AT 12Z
SUNDAY WILL SLOWLY PUSH TO LOWER MI AND FAR S QUEBEC BY 12Z
MONDAY...AND DEEPEN AS IT MOVES OVER FAR E CANADA MONDAY NIGHT.
ACROSS THE UPPER GREAT LAKES...PLENTY OF COLD AIR WILL FILTER IN
BEHIND THE LOW. NW WIND GUSTS MONDAY AFTERNOON MAY TOP OUT 20 TO
NEAR 30KTS...STRONGEST ACROSS THE KEWEENAW PENINSULA AND E ALONG THE
LAKE SUPERIOR SHORELINE.
THE COLDEST DAY /TUESDAY/ WILL SEE TEMPS STRUGGLING TO GET TO THE
FREEZING MARK DURING THE DAYTIME HOURS AS COLD HIGH PRESSURE SETTLES
IN AT THE SFC...WITH NW FLOW REMAINING ALOFT. THE COLD TEMPERATURES
WILL HAVE A SIGNIFICANT IMPACT ON SNOWMELT AND RIVER LEVELS THROUGH
AT LEAST THE FIRST HALF OF THE WORK WEEK...SLOWING DOWN THE WHOLE
PROCESS. LOOK FOR 850MB TEMPS TO FALL BELOW -8C OVER THE W HALF BY
12Z WEDNESDAY...CHANGING ANY LINGERING LIGHT PRECIP TO ALL SNOW/SNOW
SHOWERS.
THE LATTER HALF OF THE WORK WEEK WILL BE MORE JUMBLED...WITH THE A
GENERAL 500MB TROUGH OVER S CENTRAL CANADA AND THE N PLAINS STATES
WEDNESDAY NIGHT. THE NAM LOOKS TO BE MUCH DEEPER WITH THE S EXTENDED
OF THE LOW FOR TH-FRI. WILL CONTINUE TO GO MIDDLE OF THE ROAD FOR
THIS LONGER TERM PERIOD. THE MID WEEK SFC HIGH WILL BE REPLACED BY
YET ANOTHER INVERTED TROUGH SETTING UP FROM THE S PLAINS THROUGH NM
AND WI AT 00Z THURSDAY. THE LATEST ECMWF HAS THE SFC LOW TRACKING
ACROSS UPPER MI THURSDAY AFTERNOON WHILE THE GFS DOESN/T HAVE IT
CROSSING UPPER MI UNTIL FRIDAY NIGHT/SATURDAY MORNING. WILL NOT JUMP
INTO THE WEEDS OF THE EXTENDED FCST AT THIS POINT DUE TO THE
UNCERTAINTY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 122 AM EDT SAT APR 12 2014
ALTHOUGH MID/HI CLDS WL BE THICKENING EARLY THIS MRNG...EXPECT
PREDOMINANT VFR CONDITIONS AND LIGHT WINDS THRU SUNRISE WITH WEAK
RDG OF HI PRES AND LLVL DRY AIR IN PLACE. BUT AS A LO PRES TAKING
SHAPE IN THE NORTHERN PLAINS MOVES INTO THE UPR MIDWEST THIS
AFTN...WDSPRD PCPN WL DVLP W-E OVER UPR MI WITH THE ARRIVAL OF
DEEPER MSTR AND DYNAMIC SUPPORT. WHERE THE AIRMASS IS COLD ENUF FOR
MAINLY SN AND THE LLVL ESE WIND WL UPSLOPE AT CMX AND SAW...PLAN ON
LIFR CONDITIONS FM LATE THIS MRNG THRU MUCH OF THE AFTN. BUT EVEN AT
IWD WHERE THE PCPN WL BE LIGHTER AND MIXED WITH RA...IFR CIGS ARE
FCST. ALTHOUGH THE STEADY PCPN WL END BY 00Z SUN... LINGERING MOIST
E WINDS/SHALLOW COLD AIR WL RESULT IN LINGERING LO CLDS/FOG/SOME
-FZDZ...ESPECIALLY AT CMX AND SAW WHERE THE FLOW WL UPSLOPE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 516 AM EDT SAT APR 12 2014
EAST WINDS WILL INCREASE TO 25 KNOTS OVER THE WRN HALF OF THE LAKE
TODAY AS THE PRES GRADIENT TIGHTENS BTWN HIGH PRES BUILDING FROM NRN
ONTARIO INTO QUEBEC AND A LOW INTO IA. WINDS ARE ALSO EXPECTED TO
INCREASE TO 30 KNOTS MONDAY OVER CNTRL AND ERN LAKE SUPERIOR BETWEEN
HIGH RPESSURE OVER THE PLAINS AND A LOW PRES SYSTE OVER THE ERN
GREAT LAKES.
&&
.HYDROLOGY...
ISSUED AT 417 AM EDT SAT APR 12 2014
FORTUNATELY...LIMITED RAINFALL AND TEMPERATURES NEAR OR SLIGHTLY
ABOVE NORMAL HAS KEPT THE SNOWMELT SIMILAR TO NORMAL SPRING
CONDITIONS. WOULD EXPECT A SLOW STEADY RISE IN RIVER LEVELS
TODAY...WITHOUT ANY LARGER RIVERS RISING ABOVE BANKFULL AT THIS TIME.
THE PROBLEM AREAS SO FAR HAVE BEEN SMALL CREEKS AND STREAMS IN DELTA
COUNTY WHERE HAVE BEEN NEAR OR OUT OF THEIR BANKS OVER THE PAST
COUPLE OF DAYS. HOWEVER...NO SIGNIFICANT IMPACTS WERE NOTED. THERE
HAS SEEN EVIDENCE OF MINOR ICE JAMES ON SOME HYDROGRAPHS OVER THE
LAST DAY OR SO...MOST NOTABLY ON THE ONTONAGON RIVER NEAR ROCKLAND
(RKLM4) AND THE FORD RIVER NEAR HYDE (FRDM4). THE RKLM4 ICE JAM SEEMS
TO HAVE MOVED DOWNSTREAM OR BROKEN UP...BUT DO NOT KNOW ABOUT THE
STATE OF THE RIVER DOWNSTREAM GIVEN A LACK OF REPORTS/RIVER ACCESS.
THE FRDM4 ICE JAM LOOKS TO HAVE RELAXED FRIDAY EVENING. CURRENTLY
HAVE ISSUED A STATEMENT FOR THAT RIVER TO WARN OF FLUCTUATING RIVER
LEVELS AND ICE IS LIKELY STILL IN THE SYSTEM. AM UNSURE OF
IMPACTS/EXTENT OF THIS ICE JAM AS RIVER BANKS/STRUCTURES ARE FAIRLY
HIGH ABOVE THE RIVER PER DISCUSSION WITH LOCAL OFFICIALS. THERE WERE
ALSO REPORTS OF MINOR ICE JAMS ON OTHER AREA CREEKS/STREAMS THAT ARE
NOT GAUGED...BUT NO IMPACTS WERE NOTED. THIS ICE BREAK UP DOES LEAD
TO SOME CONCERN FOR ICE JAMS ON OTHER RIVERS ACROSS THE
CWA...ESPECIALLY FOR RIVERS THAT EMPTY INTO THE MAINLY FROZEN GREAT
LAKES.
A LOW PRESSURE TROUGH MOVING THROUGH THE UPPER GREAT LAKES REGION
TODAY WILL LEAD TO PERIODS OF RAIN AND SNOW /MELTING AS IT FALLS/
THROUGH SATURDAY EVENING. THE CURRENT FORECAST CALLS FOR AMOUNTS TO
BE IN THE 0.30-0.50 INCH RANGE...BUT WITH COOLER TEMPERATURES
ARRIVING WITH THIS RAIN...THE IMPACT ON THE RIVERS SHOULD BE
LIMITED. EXPECT COLDER AIR TO SURGE IN SUNDAY NIGHT THROUGH THE
FIRST HALF OF THE WORK WEEK. THIS WILL SIGNIFICANTLY REDUCE OR EVEN
END THE SNOW MELT...AS HIGHS WILL ONLY BE IN THE 30S AND LOWS WILL
BE WELL BELOW FREEZING. SINCE 4-9 INCHES OF SNOW WATER EQUIVALENT
STILL REMAINS OVER PARTS OF WESTERN AND CENTRAL UPPER
MICHIGAN...THERE IS STILL PLENTY OF WATER AVAILABLE FOR THE SECOND
PERIOD OF SNOW MELT OVER THE NEXT COUPLE OF WEEKS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...KC
MARINE...JLB
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS DULUTH MN
1107 AM CDT SAT APR 12 2014
.UPDATE...
ISSUED AT 1107 AM CDT SAT APR 12 2014
THE PCPN IS NO LONGER AS WIDESPREAD AS INTENSE AS IT WAS
PREVIOUSLY FORECAST AND AS EARLIER MODELS HAD INDICATED. AS THE
BAND OF LIGHT PCPN LIFTS INTO THE ARROWHEAD...THIS HAD
IMPLICATIONS ON THE WINTER WEATHER ADVISORY. MOST NEW MODELS RUNS
HAVE BACKED OFF ON PCPN AMOUNTS FOR THE ARROWHEAD. WHILE THE NAM12
WAS STILL BULLISH ON SNOWFALL...IT WAS FAR TOO HIGH FOR THE TWIN
PORTS AREA. I THINK TEMPERATURES ARE JUST TOO WARM...AND THAT THE
NAM12 IS TOO COLD AND EXPECTING MUCH MORE ACCUMULATION THAT WE ARE
SEEING. THE RELATIVELY WARM TEMPERATURES ARE CUTTING DOWN THE
SNOWFALL ACCUMULATIONS BECAUSE THE ROADS ARE ABLE TO MELT MUCH OF
THE SNOW. THE COMBINATION OF THE WARM TEMPERATURES AND CHANGE IN
THE MODELS GAVE ME ENOUGH CONFIDENCE THAT WE ARE NOT GOING TO SEE
THE 2 TO 4 INCHES OF ACCUMULATION OF SNOW ALONG THE NORTH SHORE
THAT WE WERE PREVIOUSLY FORECASTING. I THINK A COUPLE INCHES ARE
POSSIBLE AT MOST. I CANCELLED THE WINTER WEATHER ADVISORY.
&&
.SYNOPSIS...
ISSUED AT 308 AM CDT SAT APR 12 2014
1023MB SFC HIGH IS LOCATED OVER NRN ONTARIO WITH ELONGATED SFC LOW
ACROSS CTRL PLAINS. ALOFT A VERY FAST FLOW STRETCHES FROM NRN
ROCKIES INTO WCTRL WISCONSIN ASSOCIATED WITH 30H JET CORE. AN
ASSOCIATED INCREASE IN LOW LVL JET HAS OCCURRED FROM NEB INTO SERN
SODAK. A FEW LTG STRIKES HAVE DEVELOPED NEAR NOSE OF LLJ ACROSS
ERN SODAK. SPC MESO SHOWS STRONG FRONTOGENESIS IN LOW/MID LVLS
ACROSS ERN SODAK AND SRN MN. 88D SHOWS INCREASING RETURNS ACROSS
SWRN/SRN CWA IN AREA OF SPEED CONVERGENCE AT 85H. THERMAL PROFILES
SUPPORT LIQUID AT THIS TIME BUT WITH TIME EVAPO COOLING AND DIABATIC
COOLING WILL PROMOTE A TRANSITION TO SNOW BY 12Z NEAR TWIN PORTS
AND NORTH.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CDT SAT APR 12 2014
TODAY...AN AREA OF STRONG FORCING WILL CROSS THE CWA FROM SW TO NE
BETWEEN 12Z AND 18Z. THE MAIN CHALLENGE IS PTYPE IN THE EARLY
MORNING WHEN QPF SHOULD BE LARGEST. AFTER CONSIDERING SREF
PLUMES...VARIOUS MDL SOUNDINGS....CURRENT BDRY LYR CONDITIONS AND
LATEST RADAR FEEL FAIRLY CONFIDENT THAT RAIN WILL SWITCH TO SNOW
NEAR TWIN PORTS AND ACROSS THE NORTH MN ZONES AS DIABATIC COOLING
RESULTS FROM TOP DOWN SATURATION AND INCREASING OMEGA WITHIN THE
DGZ. AREA OF POTENTIALLY SIG SNOW SHOULD OCCUR NEAR TWIN PORTS
FROM 12Z-15Z...AND AROUND 15Z-18Z OVER ARROWHEAD. PUSHED START
TIME ON ARROWHEAD BACK TO 12Z AS SNOW SHOULD NOT ARRIVE TIL MID
MORNING. TOUGH DECISION ON WHETHER TO ISSUE ADVISORY FOR DLH
VICINITY GIVEN POTENTIAL FOR A QUICK 2 TO 3 INCHES IN A FEW HRS
EARLY THIS MORNING. STILL SOME UNCERTAINTY AS TO HOW MUCH MELTING
OCCURS WITH BDRY LYR TEMPS REMAINING ABOVE ZERO THROUGH THE EVENT.
WILL LEAVE ADVISORY FOR ARROWHEAD ALTHOUGH FAST MOVING NATURE OF
THERMAL LIFT MAY LIMIT AMOUNTS SOMEWHAT. EXPECT TEMPS IN TWIN
PORTS AREA TO LOWER WITH EVAPO COOLING EARLY IN THE DAY AND THEN
CLIMB A DEGREE OR TWO IN THE AFTN HRS. ELSEWHERE WHATEVER BRIEF
BOUT OF RASN MAY OCCUR...MOST LOCATIONS SHOULD EXPERIENCE RAIN.
INCREASING PGF ACROSS THE REGION SHOULD GIVE INCREASING WINDS NEAR
TWIN PORTS AND ALONG THE NORTH SHORE.
TONIGHT...SOMEWHAT COMPLICATED SFC PRESS PATTERN DEVELOPS AS UPPER
TROF DROPS INTO NORTH DAKOTA OVERNIGHT. AS THIS OCCURS...AN
INVERTED SFC TROUGH DEVELOPS NORTHWARD FROM CTRL PLAINS TROUGH.
THIS TROUGH PUSHES ACROSS THE MN ZONES BY 12Z WITH A SHIFT IN
WINDS TO THE NORTHWEST. PRECIP WILL BE FAVORED ACROSS NWRN CORNER
OF CWA WHERE CONVERGENCE ASSOCIATED WITH A WEAK SFC REFLECTION
COMBINES WITH UPPER DIVERGENCE FROM MID LVL TROF.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 308 AM CDT SAT APR 12 2014
THE EXTENDED PERIOD WILL BE UNSETTLED WITH GREATER THAN AVERAGE
UNCERTAINTY. TEMPERATURES WILL BE BELOW NORMAL AS WELL THROUGH THE
PERIOD.
A LONG WAVE UPPER TROUGH WILL BE MOVING INTO THE CENTRAL
CONUS/CANADA SUNDAY INTO SUNDAY NIGHT. THE TROUGH WILL CONTINUE EAST
THROUGH THE EARLY PART OF NEXT WEEK...WITH MORE TROUGHING DEVELOPING
WEST OF THE REGION THEN PROGRESSING EAST THROUGH THE REST OF THE
WEEK MAKING INTO OUR AREA. A MID WEEK SYSTEM COULD BRING SOME
SIGNIFICANT SNOWFALL TO PORTIONS OF THE NORTHLAND.
MUCH OF THE NORTHLAND SHOULD BE DRY SUNDAY...WITH PORTIONS OF
NORTHWEST WISCONSIN BEING BRUSHED BY A SIGNIFICANT SYSTEM. A
STRONGER SHORTWAVE ASSOCIATED WITH THE MAIN UPPER TROUGH WILL MOVE
THROUGH SUNDAY NIGHT INTO MONDAY...BRINGING A CHANCE FOR MAINLY
LIGHT SNOW SUNDAY NIGHT. WE KEPT SOME POPS FOR SNOW SHOWERS NORTH OR
A RAIN/SNOW MIX SOUTH INTO MONDAY WITH THE UPPER TROUGH STILL OVER
THE AREA AND COLDER TEMPS ALOFT. PRECIPITATION AMOUNTS SUNDAY NIGHT
INTO MONDAY SHOULD BE LIGHT.
A BAROCLINIC ZONE WILL SET UP OVER/NEAR THE NORTHLAND EARLY TO MID
WEEK...WITH AN AREA OF LOW PRESSURE DEVELOPING AND IMPACTING THE
NORTHLAND INTO AT LEAST WEDNESDAY NIGHT AND POSSIBLY INTO THURSDAY.
THE GFS AND ECMWF ARE NOT IN VERY GOOD AGREEMENT WITH THESE FEATURES
WITH THE ECMWF FURTHER NORTH AND PROGRESSIVE WITH THE LOW.
HOWEVER...BOTH WOULD SUGGEST SOME SIGNIFICANT SNOW WILL FALL OVER
PORTIONS OF THE NORTHLAND DURING THE PERIOD FROM TUESDAY NIGHT INTO
AT LEAST WEDNESDAY NIGHT.
DIFFERENCES BETWEEN THE MODELS BECOME EVEN GREATER LATE IN THE WEEK
AS THE GFS HAS A MUCH STRONGER SOUTHERN WAVE IN THE SOUTHERN
PORTIONS OF THE TROUGH VERSUS THE LESS AMPLIFIED ECMWF. THE GFS
KEEPS AN AREA OF LOW PRESSURE OVER THE REGION...WITH SNOW OR RAIN
GOING MUCH LONGER. WE HAVE SOME POPS IN THE FORECAST FOR NOW...BUT
CONFIDENCE IS LOW.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 651 AM CDT SAT APR 12 2014
AN AREA OF RAIN...SNOW...OR A MIX WILL MOVE THROUGH THE NORTHLAND
TODAY. A MIX OF MVFR/VFR CONDITIONS COVERED THE NORTHLAND THIS
MORNING...BUT CEILINGS SHOULD GRADUALLY LOWER FOR ALL AREAS TO
MVFR AND EVEN IFR AS THE DAY PROGRESSES. THE RAP SUGGESTS LOW
LEVEL MOISTENING WILL OCCUR ACROSS MUCH OF THE NORTHLAND BETWEEN
15-17Z.
WINDS WILL BE EASTERLY TODAY...THEN WEAK TONIGHT AND GRADUALLY
TURN TO NORTH TO NORTHWEST AS THE LOW PASSES.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 38 29 39 22 / 70 20 10 20
INL 39 25 37 16 / 50 40 20 20
BRD 52 31 41 22 / 20 10 10 10
HYR 47 31 43 24 / 50 10 20 20
ASX 44 31 41 24 / 90 10 10 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LSZ121-
140>148.
&&
$$
UPDATE...GROCHOCINSKI
SYNOPSIS...CANNON
SHORT TERM...CANNON
LONG TERM...MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS DULUTH MN
651 AM CDT SAT APR 12 2014
.SYNOPSIS...
ISSUED AT 308 AM CDT SAT APR 12 2014
1023MB SFC HIGH IS LOCATED OVER NRN ONTARIO WITH ELONGATED SFC LOW
ACROSS CTRL PLAINS. ALOFT A VERY FAST FLOW STRETCHES FROM NRN
ROCKIES INTO WCTRL WISCONSIN ASSOCIATED WITH 30H JET CORE. AN
ASSOCIATED INCREASE IN LOW LVL JET HAS OCCURRED FROM NEB INTO SERN
SODAK. A FEW LTG STRIKES HAVE DEVELOPED NEAR NOSE OF LLJ ACROSS
ERN SODAK. SPC MESO SHOWS STRONG FRONTOGENESIS IN LOW/MID LVLS
ACROSS ERN SODAK AND SRN MN. 88D SHOWS INCREASING RETURNS ACROSS
SWRN/SRN CWA IN AREA OF SPEED CONVERGENCE AT 85H. THERMAL PROFILES
SUPPORT LIQUID AT THIS TIME BUT WITH TIME EVAPO COOLING AND DIABATIC
COOLING WILL PROMOTE A TRANSITION TO SNOW BY 12Z NEAR TWIN PORTS
AND NORTH.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CDT SAT APR 12 2014
TODAY...AN AREA OF STRONG FORCING WILL CROSS THE CWA FROM SW TO NE
BETWEEN 12Z AND 18Z. THE MAIN CHALLENGE IS PTYPE IN THE EARLY
MORNING WHEN QPF SHOULD BE LARGEST. AFTER CONSIDERING SREF
PLUMES...VARIOUS MDL SOUNDINGS....CURRENT BDRY LYR CONDITIONS AND
LATEST RADAR FEEL FAIRLY CONFIDENT THAT RAIN WILL SWITCH TO SNOW
NEAR TWIN PORTS AND ACROSS THE NORTH MN ZONES AS DIABATIC COOLING
RESULTS FROM TOP DOWN SATURATION AND INCREASING OMEGA WITHIN THE
DGZ. AREA OF POTENTIALLY SIG SNOW SHOULD OCCUR NEAR TWIN PORTS
FROM 12Z-15Z...AND AROUND 15Z-18Z OVER ARROWHEAD. PUSHED START
TIME ON ARROWHEAD BACK TO 12Z AS SNOW SHOULD NOT ARRIVE TIL MID
MORNING. TOUGH DECISION ON WHETHER TO ISSUE ADVISORY FOR DLH
VICINITY GIVEN POTENTIAL FOR A QUICK 2 TO 3 INCHES IN A FEW HRS
EARLY THIS MORNING. STILL SOME UNCERTAINTY AS TO HOW MUCH MELTING
OCCURS WITH BDRY LYR TEMPS REMAINING ABOVE ZERO THROUGH THE EVENT.
WILL LEAVE ADVISORY FOR ARROWHEAD ALTHOUGH FAST MOVING NATURE OF
THERMAL LIFT MAY LIMIT AMOUNTS SOMEWHAT. EXPECT TEMPS IN TWIN
PORTS AREA TO LOWER WITH EVAPO COOLING EARLY IN THE DAY AND THEN
CLIMB A DEGREE OR TWO IN THE AFTN HRS. ELSEWHERE WHATEVER BRIEF
BOUT OF RASN MAY OCCUR...MOST LOCATIONS SHOULD EXPERIENCE RAIN.
INCREASING PGF ACROSS THE REGION SHOULD GIVE INCREASING WINDS NEAR
TWIN PORTS AND ALONG THE NORTH SHORE.
TONIGHT...SOMEWHAT COMPLICATED SFC PRESS PATTERN DEVELOPS AS UPPER
TROF DROPS INTO NORTH DAKOTA OVERNIGHT. AS THIS OCCURS...AN
INVERTED SFC TROUGH DEVELOPS NORTHWARD FROM CTRL PLAINS TROUGH.
THIS TROUGH PUSHES ACROSS THE MN ZONES BY 12Z WITH A SHIFT IN
WINDS TO THE NORTHWEST. PRECIP WILL BE FAVORED ACROSS NWRN CORNER
OF CWA WHERE CONVERGENCE ASSOCIATED WITH A WEAK SFC REFLECTION
COMBINES WITH UPPER DIVERGENCE FROM MID LVL TROF.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 308 AM CDT SAT APR 12 2014
THE EXTENDED PERIOD WILL BE UNSETTLED WITH GREATER THAN AVERAGE
UNCERTAINTY. TEMPERATURES WILL BE BELOW NORMAL AS WELL THROUGH THE
PERIOD.
A LONG WAVE UPPER TROUGH WILL BE MOVING INTO THE CENTRAL
CONUS/CANADA SUNDAY INTO SUNDAY NIGHT. THE TROUGH WILL CONTINUE EAST
THROUGH THE EARLY PART OF NEXT WEEK...WITH MORE TROUGHING DEVELOPING
WEST OF THE REGION THEN PROGRESSING EAST THROUGH THE REST OF THE
WEEK MAKING INTO OUR AREA. A MID WEEK SYSTEM COULD BRING SOME
SIGNIFICANT SNOWFALL TO PORTIONS OF THE NORTHLAND.
MUCH OF THE NORTHLAND SHOULD BE DRY SUNDAY...WITH PORTIONS OF
NORTHWEST WISCONSIN BEING BRUSHED BY A SIGNIFICANT SYSTEM. A
STRONGER SHORTWAVE ASSOCIATED WITH THE MAIN UPPER TROUGH WILL MOVE
THROUGH SUNDAY NIGHT INTO MONDAY...BRINGING A CHANCE FOR MAINLY
LIGHT SNOW SUNDAY NIGHT. WE KEPT SOME POPS FOR SNOW SHOWERS NORTH OR
A RAIN/SNOW MIX SOUTH INTO MONDAY WITH THE UPPER TROUGH STILL OVER
THE AREA AND COLDER TEMPS ALOFT. PRECIPITATION AMOUNTS SUNDAY NIGHT
INTO MONDAY SHOULD BE LIGHT.
A BAROCLINIC ZONE WILL SET UP OVER/NEAR THE NORTHLAND EARLY TO MID
WEEK...WITH AN AREA OF LOW PRESSURE DEVELOPING AND IMPACTING THE
NORTHLAND INTO AT LEAST WEDNESDAY NIGHT AND POSSIBLY INTO THURSDAY.
THE GFS AND ECMWF ARE NOT IN VERY GOOD AGREEMENT WITH THESE FEATURES
WITH THE ECMWF FURTHER NORTH AND PROGRESSIVE WITH THE LOW.
HOWEVER...BOTH WOULD SUGGEST SOME SIGNIFICANT SNOW WILL FALL OVER
PORTIONS OF THE NORTHLAND DURING THE PERIOD FROM TUESDAY NIGHT INTO
AT LEAST WEDNESDAY NIGHT.
DIFFERENCES BETWEEN THE MODELS BECOME EVEN GREATER LATE IN THE WEEK
AS THE GFS HAS A MUCH STRONGER SOUTHERN WAVE IN THE SOUTHERN
PORTIONS OF THE TROUGH VERSUS THE LESS AMPLIFIED ECMWF. THE GFS
KEEPS AN AREA OF LOW PRESSURE OVER THE REGION...WITH SNOW OR RAIN
GOING MUCH LONGER. WE HAVE SOME POPS IN THE FORECAST FOR NOW...BUT
CONFIDENCE IS LOW.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 651 AM CDT SAT APR 12 2014
AN AREA OF RAIN...SNOW...OR A MIX WILL MOVE THROUGH THE NORTHLAND
TODAY. A MIX OF MVFR/VFR CONDITIONS COVERED THE NORTHLAND THIS
MORNING...BUT CEILINGS SHOULD GRADUALLY LOWER FOR ALL AREAS TO
MVFR AND EVEN IFR AS THE DAY PROGRESSES. THE RAP SUGGESTS LOW
LEVEL MOISTENING WILL OCCUR ACROSS MUCH OF THE NORTHLAND BETWEEN
15-17Z.
WINDS WILL BE EASTERLY TODAY...THEN WEAK TONIGHT AND GRADUALLY
TURN TO NORTH TO NORTHWEST AS THE LOW PASSES.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 38 29 39 22 / 90 20 10 20
INL 39 25 37 16 / 80 40 20 20
BRD 52 31 41 22 / 60 10 10 10
HYR 47 31 43 24 / 90 10 20 20
ASX 44 31 41 24 / 90 10 10 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL 9 PM CDT THIS EVENING FOR MNZ012-
020-021.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LSZ121-
140>148.
&&
$$
SYNOPSIS...CANNON
SHORT TERM...CANNON
LONG TERM...MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
601 AM CDT SAT APR 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 410 AM CDT SAT APR 12 2014
SUBTLE UPPER LEVEL WAVE MOVING INTO MINNESOTA EARLY THIS MORNING WAS
PRODUCING SCATTERED SHOWERS...WITH A FEW LIGHTNING STRIKES ACROSS A
BROAD AREA FROM NORTHERN MINNESOTA THROUGH NORTHERN IOWA. LATEST
HRRR INDICATES RAINFALL BECOMING MORE WIDESPREAD NORTH OF THE TWIN
CITIES...TO MILLE LACS LAKE OVER THE NEXT FEW HOURS. THIS MAKES
SENSE GIVEN THE STRENGTHENING LLJ OVER THE NEXT 2 OR SO
HOURS...WHICH WILL LEAD TO BETTER WAA INDUCED LIFT AND MORE AMPLE
MOISTURE. MUCAPE LOOKS TO REMAIN CONFINED TO SOUTHERN MINNESOTA INTO
WEST CENTRAL WISCONSIN...AND ANY THUNDER WILL BE ISOLATED. THIS
RAINFALL WILL MOVE QUICKLY EAST THROUGH THE FORECAST AREA THROUGH
MIDDAY...AND FILTERED SUN UNDER JUST HIGH CLOUD COVER WILL BE SEEN
THIS AFTERNOON. TEMPERATURES TODAY WILL AGAIN BE WARM AS LITTLE HAS
CHANGED IN TERMS OF THE THERMAL RIDGE OVER THE PAST FEW DAYS. FOR
TONIGHT...THE THEME WILL BE COOLING TEMPERATURES. STRONG COLD AIR
ADVECTION AT 850H WILL ENSUE BY THE OVERNIGHT HOURS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 410 AM CDT SAT APR 12 2014
WE LIKE THE BETTER CONSISTENCY AND AGREEMENT IN THE SUN-MON
TIME FRAME FOR POPS AND TEMPS. THE 12.00/06Z NAM STILL REMAINS A
BIT FARTHER NORTH WITH THE SURFACE TROUGH AND QPF AXIS ON
SUNDAY...BUT THE SOUTHERN SHIFT FROM LAST NIGHT IS ENCOURAGING AND
GIVES MUCH US HIGHER CONFIDENCE IN KEEPING A VAST MAJORITY OF THE
PRECIP ACROSS NORTHEAST IA AND SOUTHWEST WI NEAR THE 850-700MB
FGEN. THE GFS LOOKS ABOUT THE SAME AS WHAT WE WERE SEEING LAST
NIGHT AT THIS TIME AND THE ECMWF MIGHT JUST BE A HAIR NORTH AND
NOW IS IN CLOSER AGREEMENT WITH THE GFS. AT THIS POINT...SOUTHERN
MN AND WEST CENTRAL WI MISS OUT ON MUCH OF THE RAIN...BUT WE STILL
HAVE CHANCE-TO-LIKELY POPS IN SOUTH CENTRAL MN AND WEST CENTRAL WI
AND EVEN SOME SMALL POPS IN THE TWIN CITIES METRO FOR LIGHT RAIN
SHOWERS AND A DECENT CHANCE OF A CHANGEOVER TO LIGHT SNOW SUNDAY
NIGHT IF PRECIP REMAINS WHEN THE ATMOSPHERIC COLUMN COOLS WITH THE
PRESENCE OF COLD ADVECTION. THE LIGHT RAIN MIGHT JUST COME TO AN
END BEFORE THE TEMPS COOL ENOUGH...SO WE HAVE ARE NOT TOO
CONCERNED ABOUT ACCUMULATING SNOW. SUNDAY-WEDNESDAY STILL LOOKS
COLD AND AS MENTIONED ABOVE. THE THERMAL PROFILE OFF THE GFS NOW
MATCHES THE PREVIOUS ECMWF RUNS THAT SHOW A SLOWER/DEEPER TROUGH
AND A NICE 850MB COLD POCKET. THE MORE AMPLIFIED PATTERN EARLY
NEXT WEEK IS ALSO BEING HIGHLIGHTED IN THE NAM/GEM NOW. SO...JUST
AS WE GET APRIL`S MONTHLY TEMPERATURE BACK UP NEAR NORMAL...WE
SHOULD DROP IT BACK DOWN WITH 20S FOR LOWS AND 40S FOR HIGHS. BY
LATE NEXT WEEK THE GFS AND ECMWF SOLUTIONS SHOW MAJOR DEVIATION
FROM ONE ANOTHER AND THEIR ENSEMBLE COUNTER PARTS ARE CLOSER TO
ONE ANOTHER. IT`S MAINLY A TIMING ISSUE...SO WE HAVE LOW
CONFIDENCE IN TEMPERATURE SPECIFICS ON THURSDAY...FRIDAY AND
SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 552 AM CDT SAT APR 12 2014
RAIN WILL HAVE MOVED EAST OF AXN/STC/RWF BY 12Z...WITH MSP ON THE
FRINGE...AND RNH AND EAU HAVING TO ENDURE A FEW HOURS OF LIGHT
RAIN. MAIN AVIATION CONCERN TODAY IS ACROSS EASTERN SITES...WHERE
THE POSSIBILITY OF LOWER CEILINGS DEVELOPING EXISTS. RAP IS
ADAMANT IN 850H MOISTURE BUT NAM DISAGREES. THE HRRR INDICATES MSP
WILL BE ON THE EDGE...WITH BEST CHANCES FOR MVFR THREATENING RNH
AND EAU. FOR NOW...LEANED TOWARD THE NAM IN SUPPORT OF DRY AIR
PREVAILING...DESPITE RAINFALL EARLY THIS MORNING. AMOUNTS THIS
MORNING WILL BE LIGHT. DID KEEP A MENTION OF STRATUS IN THE
FORECAST FOR MSP/RNH/EAU AND THIS WILL HAVE TO BE MONITORED AND
TWEAKED BY UPCOMING SHIFTS.
KMSP...ON THE PERIPHERY OF THE DEPARTING SHOWERS BY 12Z. THESE
SHOWERS PROVED TO BE A NON ISSUE IN TERMS OF VISIBILITY...AND WILL
QUICKLY EXIT THE METRO THIS MORNING. AS MENTIONED ABOVE...LOW
LEVEL STRATUS COULD DEVELOP/LINGER AT MSP...BUT THE BEST CHANCES
LOOK FURTHER EAST.
/OUTLOOK FOR KMSP/
SUN...MAINLY VFR. CHC MVFR CIGS/SHRA. WINDS N 10-15 KT.
MON...VFR. WINDS NW 10-15 KT.
TUE...VFR. WINDS NW 10 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...FLOOD WATCH THROUGH TUESDAY MORNING FOR WIZ025-026-028.
&&
$$
SHORT TERM...SPD
LONG TERM...CLF
AVIATION...SPD
AREA FORECAST DISCUSSION
NWS JACKSON MS
1003 PM CDT SUN APR 13 2014
.UPDATE...
EVENING AREA RAOB ANALYSES REVEAL PLUME OF VERY RICH GULF MOISTURE
BEGINNING TO SURGE INLAND OVER LA AHEAD OF A STRONG COLD FRONT WITH
SOUTHWEST FLOW ALOFT. HOWEVER...VERY DRY MID LEVEL AIR INDICATED BY
JAN/LIX SOUNDINGS SHOW QUITE A BIT OF MOISTENING STILL NEEDS TO TAKE
PLACE. LATEST HRRR GUIDANCE HAS BEEN INDICATING THAT MOISTURE/
INSTABILITY WILL INCREASE SUFFICIENTLY FOR A CONVECTIVE SYSTEM TO
MOVE ACROSS NORTHERN/WESTERN PORTIONS OF THE ARKLAMISS LATE TONIGHT
AND BRING A POTENTIAL FOR SEVERE WEATHER AND EVENTUALLY FLOODING AS
THE OUTFLOW ASSOCIATED WITH THE SYSTEM STALLS. IT SEEMS TO BE LOCKING
ONTO AN AREA ALONG THE I-20 CORRIDOR FROM NEAR RAYVILLE TO JACKSON
FOR HEAVIEST BAND OF RAINFALL (PERHAPS UP TO AROUND 5 INCHES BY EARLY
MORNING)...WHICH COULD HAPPEN GIVEN VEERING LOW LEVEL WIND PROFILES
AND INCREASINGLY UNIDIRECTIONAL DEEP LAYER FLOW IN EXIT REGION OF
SUBTROPICAL JET STREAM. HAVE NOT MADE ANY SIGNIFICANT ADJUSTMENTS TO
THE FORECAST AND WILL KEEP FLOOD WATCH CONFIGURATION THE SAME FOR
NOW. /EC/
&&
.PREV DISCUSSION... /ISSUED 349 PM CDT SUN APR 13 2014/
.PERIODS OF POTENT STORMS AND HEAVY RAINFALL EXPECTED STARTING LATE
TONIGHT...
SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT)...
BUSY FORECAST IN THE SHORT TERM HIGHLIGHTED BY THE POTENTIAL FOR
SEVERE WEATHER AND SOME HEAVY RAINS TONIGHT INTO TUE NIGHT..FOLLOWED
BY THE POTENTIAL FOR A MID APRIL FREEZE ACROSS A GOOD PORTION OF THE
AREA TUE NIGHT. BREEZY CONDITIONS HAVE DEVELOPED ACROSS THE REGION
THIS AFTERNOON AS EXPECTED AND WILL CONTINUE THE WIND ADVISORY FOR
THE DELTA INTO THIS EVENING.
FOR TONIGHT...THE EVENING WILL START OFF RATHER QUIET AS CLOUDS
INCREASE AHEAD OF A DIGGING SYSTEM OVER THE CENTRAL CONUS. A
WEAKENING UPPER LEVEL SPEED MAX AT THE BASE OF THE TROUGH WILL
APPROACH THE ARKLAMISS TONIGHT...CONCURRENT WITH A NORTHWARD SURGING
MOISTURE/INSTABILITY TONGUE. FORCING FOR ASCENT WILL BE SUFFICIENT
FOR SHOWERS AND THUNDERSTORMS TO BEGIN OVERSPREADING THE REGION FROM
THE WEST AND SOUTHWEST AS WE HEAD TOWARD MIDNIGHT...SPREADING EAST
THROUGH THE NIGHT. HI-RES MODELS CONTINUE TO HINT AT POTENTIAL FOR
SOME OF THE ACTIVITY ON THE LEADING EDGE TO BE ON THE STRONGER SIDE.
WHILE LAPSE RATES AREN`T TERRIFIC WHICH SHOULD LIMIT THE LARGE HAIL
POTENTIAL...LOW LEVEL AND DEEP LAYER SHEAR WILL BE STRONG ENOUGH TO
HELP ORGANIZE SOME UPDRAFTS AND YIELD A NOCTURNAL DAMAGING WIND AND
TORNADO RISK. CURRENT AREAS HIGHLIGHTED WITH THE GREATEST RISK IN
THE INHERITED HWO/GRAPHICS LOOK GOOD AND WILL KEEP AS IS. THIS
ACTIVITY LOOKS TO PASS OFF TO THE EAST SHORTLY AFTER SUNRISE.
REST OF THE DAY MONDAY...LIKE WE`VE BEEN HIGHLIGHTING...THERE LOOKS
TO BE A LULL IN THE MORE ROBUST CONVECTION DURING THE MORNING HOURS
TOMORROW ALTHOUGH AT LEAST SCATTERED SHOWER ACTIVITY SHOULD LINGER.
BY EARLY-MID AFTERNOON STOUT HEIGHT FALLS ON THE LEADING EDGE OF THE
APPROACHING TROUGH WILL INVIGORATE CONVECTION ALONG AND JUST AHEAD
OF THE APPROACHING COLD FRONT. WHILE THE BETTER LOW LEVEL SHEAR WILL
HAVE SHUNTED EAST BY THIS TIME...SUFFICIENT LAPSE RATES COMBINED
WITH THE STRONG FORCING WILL CERTAINLY ALLOW A DAMAGING WIND AND
LARGE HAIL RISK TO DEVELOP. AND ALTHOUGH THE TORNADO RISK WILL BE
LOWER THAN TONIGHT...ITS STILL NON-ZERO...ESPECIALLY ACROSS
SOUTHEASTERN AREAS WHERE BETTER INSTABILITY SHOULD BE REALIZED. ONCE
AGAIN...I`M NOT SURE ANY ADJUSTMENTS TO THE AREAL EXTENT OF THESE
HAZARDS WE HAVE HIGHLIGHTED IS NEEDED AND WILL KEEP THINGS AS IS. BY
MID TO LATE EVENING THE MODELS ARE CONSISTENT SHOWING THE COLD FRONT
PASSING EAST OF THE AREA BRINGING THE SEVERE WEATHER RISK TO AN END.
AS FOR THE HEAVY RAINS...THE 12Z NAM AND GFS BOTH SHOW A SWATH OF
1.5-2.5 IN EXTENDING FROM VKS TO CBM WITH LOWER AMOUNTS TO THE NORTH
AND SOUTH OF THIS LINE THROUGH TUE MORNING. 12Z EURO HAS MORE OF A
WIDESPREAD 1.5-2 IN ACROSS THE FA WITH SOME HIGHER AMOUNTS ACROSS
EASTERN MS. LOCAL WRF SHOWS HIGHEST SWATHS OF PRECIP (GREATER THAN 2
IN) ACROSS AREAS GENERALLY ALONG AND SOUTH OF THE NATCHEZ TRACE
THROUGH TOMORROW AFTERNOON. WHILE CONFIDENCE IS NOT OVERLY HIGH ON
JUST WHERE THE HIGHEST RAINFALL TOTALS WILL COME IN...IT DOES LOOK
LIKE THE MOST PROBABLE AREAS WILL BE ALONG AND SOUTH OF THE TRACE
AND HAVE HOISTED A FLASH FLOOD WATCH FOR THESE AREAS STARTING
TONIGHT AND CONTINUING INTO MON NIGHT. WHILE THE LARGER SCALE MODELS
ARE HESITANT SHOWING MUCH MORE THAN 1 TO PERHAPS 2.5
INCHES...CONVECTIVE NATURE OF THE ACTIVITY TONIGHT AND AGAIN
TOMORROW AFTERNOON SHOULD EASILY LEAD TO HIGHER AMOUNTS IN CERTAIN
AREAS. THIS WILL EASILY POSE A FLASH FLOOD RISK IF THESE HEAVIER
SWATHS FALL IN VICINITY OF ALREADY SWOLLEN CREEKS AND RIVERS.
THE RAINS LOOK TO FINALLY PUSH EAST OF THE REGION BY TUE MORNING
WITH DRY AIR FILTERING IN. WE COULD BE LOOKING AT THE NEED FOR A
WIND ADVISORY LATE MON NIGHT INTO TUE MORNING IN WAKE OF THE FRONT
AS A TIGHT PRESSURE GRADIENT DEVELOPS. WE`LL BE KEEPING AN EYE ON
THAT SITUATION.
CHILLY HIGH PRESSURE WILL BE FIRMLY IN PLACE WED MORNING SETTING UP
IDEAL RADIATIONAL COOLING CONDITIONS. OVERNIGHT LOWS WILL DEFINITELY
HAVE A CHANCE TO FALL NEAR OR BELOW FREEZING FOR MANY
AREAS...ESPECIALLY THE FURTHER NORTH YOU GO. A LATE SEASON FREEZE
WARNING MAY VERY WELL BE NEEDED FOR THIS TIME. STAY TUNED. /BK/
LONG TERM...(WEDNESDAY THROUGH SUNDAY)...
CONDITIONS WILL THANKFULLY BE WARMING UP ON WEDNESDAY...ALTHOUGH IT
WILL PROBABLY TAKE UNTIL THURSDAY TO MAKE IT BACK CLOSE TO AVERAGE
FOR THE LATTER HALF OF APRIL. HIGHER CLOUDS WILL INCREASE SOME
DURING THIS TIME FRAME AS UPPER LEVEL TROUGH ENERGY AGAIN DIGS A BIT
BACK TO OUR WEST.
THE OPERATIONAL GFS MODEL AND A FAIR NUMBER OF ITS ENSEMBLE MEMBERS
STILL SEEM TO BE MOST AGGRESSIVE IN RESOLVING THIS NEXT BATCH OF
INCOMING TROUGH ENERGY IN SIZABLE RAIN CHANCES OVER AN EXTENDED
PERIOD FROM LATE THURSDAY THROUGH FRIDAY. CONVERSELY...THE MORE
TRUSTWORTHY LONG RANGE MODEL PERFORMER WHICH IS THE EUROPEAN MODEL
IS NOT IS NOT SO GUNG HO. PART OF THE REASON (BEYOND PAST
PERFORMANCE LOGIC) TO THINK THE EURO HAS THE RIGHT IDEA IS THAT THE
INCOMING TROUGH SEEMS TO BE LOOSELY LINKED TO A GLOBAL EQUATORIAL
OSCILLATION AND TRIGGERING A BULK OF CONVECTION AND MOISTURE
CONVERGENCE WAY TO THE SOUTH OF THE GULF COAST. FOR NOW I CUT BACK
MEX (GFS-BASED) POPS ALTHOUGH STILL KEEP SOME SMALL CHANCES OF RAIN
IN PLAY.
BEYOND THE END OF THE WORK WEEK THE FORECAST LOOKS MORE MUDDLED INTO
NEXT WEEKEND WITH CONFLICTING MODEL SIGNALS. HOWEVER...AT THIS POINT
THERE IS STILL POTENTIAL FOR NEXT WEEKEND TO COME AROUND WITH NO
PROSPECT OF INCLEMENT WEATHER. /BB/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 66 73 42 54 / 100 100 63 4
MERIDIAN 64 78 47 59 / 79 100 82 11
VICKSBURG 66 75 40 56 / 100 100 48 0
HATTIESBURG 66 80 50 60 / 76 100 73 11
NATCHEZ 67 76 37 53 / 100 100 45 3
GREENVILLE 67 68 37 53 / 100 100 43 0
GREENWOOD 67 70 38 54 / 100 100 56 3
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...FLASH FLOOD WATCH FROM 1 AM CDT MONDAY THROUGH LATE MONDAY NIGHT
FOR MSZ027>033-035>066-072>074.
LA...FLASH FLOOD WATCH FROM 1 AM CDT MONDAY THROUGH LATE MONDAY NIGHT
FOR LAZ009-015-016-023>026.
AR...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
903 PM CDT Sun Apr 13 2014
.UPDATE:
Issued at 903 PM CDT Sun Apr 13 2014
Two areas of SHRA/TSRA of interest at the moment. The first area
moved thru southeast MO and into STL Metro earlier this evening
and has dropped up to 1.25" of rain in spots with many areas
receiving between 0.3 and 0.75" in the main area of effect. No
severe weather is anticipated here with the atmosphere worked over
well and not that unstable. Some elevated instability, though, has
produced imbedded thunder.
The other area is a squall line that had developed over western MO
and eastern KS this afternoon and has progressed steadily
eastward, but has thus far produced wind gusts up to 50mph. Severe
thunderstorm watch #75 continues for a reduced area in east-
central MO until midnight CDT, but anticipate this watch being
cancelled probably around 10-1030pm given current trends and
timing of progression of thunderstorm line.
All of this will exit STL metro during the early overnight and
late tonight in southwest IL. The next round of more stratiform
frontogenetical pcpn is not anticipated until mid-late Monday
morning in central MO, expanding elsewhere later on Monday. It is
with this area of pcpn, and behind an increasingly chilly airmass,
that some snow will be possible, but it remains doubtful on
ability to accumulate considering warm ground and surface temps
above freezing throughout. Nevertheless, the mere presence of
falling snow in mid-April rather unusual in these parts.
TES
&&
.SHORT TERM: (Through Late Tonight)
Issued at 359 PM CDT Sun Apr 13 2014
(Tonight-Monday Night)
Main question tonight will be severe weather chances. Large area of
stratiform rain currently over the CWA may suppress these chances as
latest SPC objective MUCAPE analysis is mostly below 500 j/kg except
across northern Missouri and west central Illinois. The latest runs
of the HRRR has been trending toward weaker storms these evening
because weaker instability. However, if the rain can mover out of
the area, there are very steep lapse rates over the Central Plains
that could help quickly destabilize the atmosphere ahead of the line
of the storms currently over eastern Kansas. Deep layer shear
between 00-03Z will be between 35-50kts which will be sufficient for
organized severe storms.
Otherwise, forecast did not require too much changes as I still
expect front to march southeast across the CWA tonight.
Thunderstorm threat will end with the front and change to a plain
cold rain. Have kept likely chances to for rain on Monday as the
ECMWF/GFS/NAM all mid-level frontogenesis moving across the region
during the day. Also added likely chances over the eastern counties
on Monday evening as ascent from the mid level trough will not clear
the CWA until overnight Monday night. Forecast soundings and
critical thicknesses still point to snow mixing with the rain from
northwest to southeast during the day on Monday. Do not have any
accumulating snow at the moment as the low atmosphere will be rather
warm during the day, as will the surface temperatures after this
unseasonably warm weekend.
With the much colder air moving into the area, temperatures will
fall below freezing over the entire CWA on Monday night. Many areas
will see temperatures in the mid to upper 20s.
Britt
.LONG TERM: (Monday through Next Sunday)
Issued at 359 PM CDT Sun Apr 13 2014
(Tuesday-Sunday)
Upper trough will move east of the area by Tuesday bringing dry
weather for mid week. While Monday night looks like the coldest,
Tuesday night will likely still have temperatures around freezing
before lows become more seasonable later in the week.
While the ECMWF has trended deeper and consequently slower with the
trough that will move through the central CONUS late this week, it
is still not as deep as the GFS or the Canadian GEM. Will stick
with the more consistent ECMWF as the GFS is quicker to move the
front through the area on Thursday night than it was before. Will
keep Thursday dry with the front staying to the northwest most of
the day with a chance of showers Thursday night and Friday as the
front moves across the area. By next weekend, winds turn out of the
southwest quickly behind a retreating high allowing gulf moisture to
move north from the Gulf quickly into the area.
Britt
&&
.AVIATION: (For the 00z TAFs through 00z Monday Evening)
Issued at 512 PM CDT Sun Apr 13 2014
Cold front extending from a weak surface low over southeast IA
southwest through northwest MO and southeast KS will move sewd
through UIN and COU this evening, and through the St Louis metro
area just after 06z Monday. Scattered showers will continue ahead
of the front early this evening with a line of thunderstorms
along the cold front moving through the taf sites later this evening.
Relatively strong and gusty sly surface winds will veer around to
a nwly direction after fropa and remain strong and gusty late
tonight and Monday due to a tight surface pressure gradient.
Ceilings will likely fall into the IFR catagory behind this front.
There will be some post frontal light rain on Monday, possibly
mixing with or changing to light snow in UIN and COU as colder air
continues to filter sewd into the area.
Specifics for KSTL: Showers and thunderstorms over south central
MO will move northeastward into STL later this evening, while a
line of thunderstorms along the cold front over northwest and west
central MO moves into the STL area by late evening. Strong and
gusty sly winds will veer around to a wly direction late tonight
after fropa and a nwly direction Monday morning. The wind will
remain strong and gusty through Monday, then diminish Monday night
as a surface ridge approaches and the surface pressure gradient
relaxes. The cloud ceiling will lower into the IFR catagory late
tonight after fropa, then rise into the MVFR catagory Monday
afternoon or evening. Periods of light rain can be expected on
Monday, possibly changing to a little light rain/snow mix before
ending Monday evening.
GKS
&&
.CLIMATE:
RECORD LOWS FOR 4/15:
STL - 27 IN 1928
COU - 25 IN 1928
UIN - 24 IN 1928
FAM - 24 IN 1928
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
409 PM CDT Sat Apr 12 2014
.SHORT TERM...(This Evening through Monday Night)
Issued at 408 PM CDT SAT APR 12 2014
Tonight:
Frontal boundaries will likely be the focus for most of the
convection tonight. A warm front extends from a weak low near OMA
through northern IL. A diffuse area of low pressure over southwest
KS is connected to the OMA low by a very weak cold front.
Strong and gusty southerly winds have pulled up the season`s first
large swath of gulf moisture into KS/MO as noted by 60ish dewpoints
while southwesterly h8 winds spread an elevated mixed layer across
KS and MO resulting in a moderately strong cap.The end result is the
warmest temperatures of the year with MLCAPEs around 2500 J/kg but
marginal 0-6km shear around 35 kts. Evening convective activity will
likely be closely tied to the IA warm front. Best severe threat will
reside over IA with isolated severe storms possible over northwest
MO mainly this evening. Large hail would be the most likely severe
threat. A h7 shortwave is progged to lift northeast through northern
KS/NE and activate this warm front. Last 4-5 runs of the HRRR has
consistently shown scattered convection popping up along this
boundary around 22z. The convection further south which the HRRR and
RAP develop over east central KS is a bit suspicious as it forms
within the well capped environment with no boundary nearby. Wouldn`t
be surprised if it actually form further west along the dryline over
central KS where some cu has recently formed. Prefer to limit the
evening convection to northwest and north central MO. Also have low
confidence in the NAM and GFS propagating an MCS southward into east
central KS and west central MO by 06Z. Overall, will concentrate
highest PoPs across northern MO and lower them south of the MO River.
Sunday-Sunday night:
A broad upper trough over the desert southwest is expected to lift
northeast on Sunday and enhance the downstream lift via
increasing/expanding upper level diffluence. This in turn will lead
to widespread convection with heavy rains likely. Scattered
convection will likely be ongoing Sunday morning and this plus
extensive low level cloud cover will make it difficult to realize the
moderate instability the soundings show. Should some breaks occur of
any meaningful length of time then we could tap into this instability
and give a boost to our severe threat. For now strong storms are
possible south of the MO River on Sunday with a minimal severe
threat. The main weather threat will be from heavy rains due to very
efficient deep, tropical-like convection, which could train during
the afternoon and early evening.
The true cold front currently lies form eastern ND through west
central SD which will reinforce the frontal boundary on Sunday. A
second and much deeper northern upper trough will push this front
southeast with strong cold air advection rushing in Sunday night.
Inspection of Bufr soundings suggest the rain could mix with snow
over parts of northwest MO late Sunday night.
Monday-Monday night:
A very raw and blustery day with temperatures 20 degrees below
average. While the NAM had previously been discounted as being too
cold and generating several inches of snow the latest GFS and ECMWF
have been trending colder and also generating at least a rain/snow
mix. Started trending colder yesterday and continue doing so today.
Areas of light rain mixed with snow seems plausible if not likely
Monday morning. Will hold off on mentioning any snow amounts for now.
Very cold temperatures will settle in overnight Monday as skies
clear out. Will see sub-freezing temperatures everywhere with many
locations experiencing several hours of temperatures below 28F at
which water freezes inside most plants. Will be issuing headlines
eventually for Monday night/Tuesday morning.
.LONG TERM...(Tuesday through Saturday)
Issued at 408 PM CDT SAT APR 12 2014
Tuesday-Saturday
After a chilly start Tuesday morning, temperatures will steadily
rebound Tuesday into Wednesday, with highs primarily in the 50s and
60s respectively. Model solutions vary greatly with regards to
timing, amplification/strength, and placement of the next upper
trough to affect the area Thursday or Friday. This provides
relatively high uncertainty to the expected weather during this
period, and likewise the degree of cooler weather to follow upon the
frontal passage. As for temperatures during the period, readings
should remain slightly below climatological normals for this time of
year.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1251 PM CDT SAT APR 12 2014
Challenging forecast. Immediate forecast concern are the strong and
gusty southerly winds. Should lose the gusts after sunset and diurnal
mixing ceases.
Warm elevated mixed layer has overspread eastern KS/western MO and
will effectively inhibit convective development through tonight. Best
chance for showers and thunderstorms tonight will likely lie from far
northeast KS across northern MO and areas northward. A few
convective allowing models generate isolated convection late this
afternoon and early evening from east central KS into northwest MO
but confidence is low for it to form and then also reach the
terminals. Also have low confidence in 12z NAM and GFS developing a
MCS north of the terminals this evening and propagating southward
through eastern KS/west central MO. Believe the cap will be difficult
to break until the NE/IA cold front moves through the region Sunday
afternoon. There will be a much greater chance for rain after 18z
Sunday.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
SHORT TERM...MJ
LONG TERM...Blair
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
655 PM CDT SUN APR 13 2014
.UPDATE...
ISSUED AT 646 PM CDT SUN APR 13 2014
WILL BE ALLOWING WINTER WEATHER ADVISORY TO EXPIRE AT 7PM FOR
PARTS OF NORTHEAST AND EAST CENTRAL NEBRASKA. BAND OF HEAVY SNOW
IS BEGINNING TO DIMINISH AS UPPER SUPPORT DRIFTS TO THE EAST. CAN
EXPECT A PERSISTENT BAND FROM NEAR COLUMBUS TO ONAWA TO SLOWLY
SINK SOUTHEAST BUT BECOME LESS INTENSE WITH TIME THIS EVENING.
COULD STILL SEE SOME ADDITIONAL ACCUMULATIONS IN THIS BAND OF UP
TO AN INCH...BUT IMPROVING VISIBILITIES AND DECREASING INTENSITY
OF SNOW SUGGESTS ADVISORY LEVEL SNOWS WILL BE OVER SOON. TREND OF
RAIN MIXING WITH THEN CHANGING TO SNOW SHOULD CONTINUE FARTHER
SOUTHEAST INTO SOUTHEAST NEBRASKA AND SOUTHWEST IOWA AS
TEMPERATURES DROP TOWARD FREEZING THIS EVENING. HOWEVER WITH
DECREASING INTENSITY...ANY SNOW AMOUNTS NEAR AND SOUTHEAST OF
INTERSTATE 80 WILL BE MINIMAL.
&&
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY)
ISSUED AT 220 PM CDT SUN APR 13 2014
PRIMARY FORECAST CONCERN WILL BE WITH THE FIRST 12 HOURS OF THE
FORECAST AND ITS VARIETY OF WEATHER ACROSS THE AREA.
COLDER AIR CONTINUES ITS SLOW ADVANCE INTO EASTERN NEBRASKA AT 19Z
WITH SNOW NOW FALLING ACROSS NORTHEAST NEBRASKA WEST OF A COLUMBUS
TO SIOUX CITY LINE. SHORT RANGE MODELS SUCH AS THE HRRR SUGGEST
MAIN ORIENTATION OF THE SNOW BAND WILL GENERALLY SETUP IN AN AREA
BOUNDED BY COLUMBUS TO TEKAMAH ON THE SOUTH AND YANKTON TO NELIGH
ON THE NORTH THROUGH THE REMAINDER OF THE AFTERNOON AS MID LEVEL
CLOSED LOW TRACKS EAST INTO CENTRAL IOWA. SNOW THEN SPREADS EAST
AND ENDS FROM THE WEST DURING THE EVENING ACROSS THE REMAINDER OF
EASTERN NEBRASKA AND SOUTHWEST IOWA AS THE MID LEVEL LOW CONTINUES
TO LIFT TOWARD THE GREAT LAKES REGION AND THE SURFACE LOW MOVES
INTO NORTHERN ILLINOIS. EXPECT SNOW TO END SHORTLY AFTER MIDNIGHT
IN THE FAR SOUTHEAST CORNER OF THE FORECAST AREA. WILL LIKELY
EXPAND WINTER WEATHER ADVISORY ACROSS THIS AREA THROUGH THE 00Z
TIME FRAME IN LINE WITH EXPECTED SNOW. CURRENT INDICATIONS ARE FOR
1 TO 3 INCH ACCUMULATIONS BY EVENING IN THE ADVISORY AREA WITH AN
INCH OR LESS ELSEWHERE THROUGH THE EVENING.
WILL ALSO EXPAND WIND ADVISORY ACROSS REMAINDER OF SOUTHEAST
NEBRASKA AND SOUTHWEST IOWA AND EXTEND THROUGH 03Z.
WEATHER CONDITIONS IMPROVE FOR THE AREA AFTER TONIGHT ALTHOUGH
TEMPERATURES WILL BE ON THE COOL SIDE MONDAY. ANOTHER CLIPPER
MOVES INTO THE NORTHERN PLAINS TUESDAY WITH WARMER AIR RETURNING
TO THE AREA IN ADVANCE OF THIS SYSTEM. COLD FRONT THEN MOVES SOUTH
INTO THE AREA ON WEDNESDAY WITH ANOTHER CHANCE OF RAIN OR SNOW.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 220 PM CDT SUN APR 13 2014
COOL AND WET START TO THE EXTENDED PERIOD AS PREVIOUSLY MENTIONED
COLD FRONT MOVES SOUTH OF THE AREA WITH ANOTHER COLD UPPER TROUGH
DEVELOPING OVER THE CENTRAL PART OF THE COUNTRY. DAY TO DAY
WARMING FOLLOWS THIS SYSTEM FOR FRIDAY THROUGH SUNDAY
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 646 PM CDT SUN APR 13 2014
AREAS OF LIGHT SNOW AND A MIX OF LIGHT RAIN AND SNOW WILL
OCCASIONALLY DROP CIGS TO NEAR FL010 AND VSBYS BETWEEN 1SM AND 2SM
IN THE KLNK AND KOMA THROUGH THE 04Z TO 06Z TIMEFRAME. THAT
PRECIPITATION AND CIGS WILL BE MOVING EAST OF THE AREA NEAR AND
AFTER 06Z...WITH IMPROVING CONDITIONS THEREAFTER. EXPECT VFR
CONDITIONS AT ALL SITES AFTER 08Z. STRONG NORTH WINDS OF 20 TO
35KT WILL PERSIST THROUGH ABOUT 02Z THEN DECREASE INTO THE 15 TO
25KT RANGE. EXPECT THOSE WINDS TO PERSIST THROUGH MONDAY AFTERNOON
BEFORE BEGINNING TO DIMINISH.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR NEZ015>018-030>034-
042>045-050>053-065>068-078-088>093.
IA...WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR IAZ043-055-056-069-
079-080-090-091.
&&
$$
UPDATE...DERGAN
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...DERGAN
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
623 PM CDT SUN APR 13 2014
.UPDATE...
ISSUED AT 623 PM CDT SUN APR 13 2014
JUST UPDATED THE FORECAST TO CANCEL THE WINTER WEATHER ADVISORY
FROM CUSTER...GARFIELD AND WHEELER COUNTIES. SNOW HAS ENDED IN
THESE AREAS...HOWEVER SOME VERY LIGHT SNOW IS POSSIBLE ACROSS THE
SOUTHEASTERN NEBRASKA PANHANDLE AND FAR SOUTHWESTERN NEBRASKA THIS
EVENING. RADAR RETURNS FROM COLORADO AND FAR SERN
WYOMING...INDICATE A NICE AREA OF LIGHT TO MODERATE SNOW IN NERN
COLORADO IN ASSOCIATION WITH A TRAILING DISTURBANCE OVER FAR SERN
UT. THE LATEST RAP AND NAM SOLNS...ALLOW THIS SNOW TO DRIFT INTO
THE FAR SOUTHWESTERN FORECAST AREA THROUGH MID EVENING...THEN
SHIFTING IT SOUTH INTO KANSAS BY LATE EVENING. LITTLE OR NO
ADDITIONAL ACCUMULATIONS ARE EXPECTED WITH ANY SNOW WHICH MOVES
INTO THE FORECAST AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 345 PM CDT SUN APR 13 2014
AT 19Z...WATER VAPOR IMAGERY SHOWED A SHORTWAVE TROUGH MOVING ACROSS
CENTRAL NEBRASKA/KANSAS WITH A GOOD RIDGE DOWNSTREAM ACROSS THE
EASTERN HALF OF THE COUNTRY. LOOKING UPSTREAM...ANOTHER SHORTWAVE
TROUGH HAD BEEN DIGGING SOUTH THROUGH THE DAY...FROM THE PACIFIC
NORTHWEST DOWN OVER UTAH AT THE CURRENT TIME. THE SHORTWAVE OVER THE
LOCAL AREA HAD AN ASSOCIATED SURFACE LOW IN EASTERN KANSAS...WITH A
COLD FRONT INTO THE SOUTHERN PLAINS AND A WARM FRONT TO THE
NORTHEAST INTO IOWA. COLD AIR ADVECTION WAS ONGOING THROUGH THE
DAY...AND AS THE WET BULB TEMPERATURE DROPPED BELOW THE FREEZING
MARK BY EARLY TO MID MORNING...MUCH OF THE PRECIPITATION LOCALLY
FELL AS SNOW. MID LEVEL FRONTOGENESIS HAD BEEN ONGOING THROUGH THE
DAY AS THE 700MB LOW TRACKED JUST SOUTHEAST OF THE FORECAST
AREA...FROM NORTHWEST KANSAS INTO SOUTH CENTRAL NEBRASKA.
PRECIPITATION DEVELOPED IN THIS AREA. THE FRONTOGENETICAL FORCING
HAS SHIFTED EAST THROUGH THE DAY...WHICH ALLOWED THE PRECIPITATION
TO ALSO SHIFT EAST THROUGH THE DAY AND BY MID AFTERNOON HAS MOSTLY
ENDED. THERE WERE SEVERAL STRONGER BANDS OF SNOW THAT
DEVELOPED...WHICH DROPPED AS MUCH AS 5 INCHES OF SNOW IN PARTS OF
THE FORECAST AREA.
AT 20Z...MODERATE SNOWFALL DID CONTINUE FROM CURTIS TO BROKEN BOW TO
ALMERIA...WITH VERY LIGHT SNOW STILL IN AREAS TO THE WEST. THE
WINTER WEATHER ADVISORY WILL BE CANCELLED EARLY FOR THOSE LOCATIONS
WHERE THE HEAVIER SNOW HAS ENDED AS HAZARDOUS WEATHER CONDITIONS
HAVE GENERALLY ENDED. THERE COULD BE A FEW LOCATIONS WHERE ROADWAYS
MAY REMAIN SLICK...BUT ANY FOLLOWING WEATHER CONDITIONS WILL NOT
MAKE THINGS WORSE.
WINDS WILL REMAIN STRONG INTO THE EVENING...BUT WILL START TO
SLOWLY DIMINISH AS THE SURFACE LOW CONTINUES TO THE NORTHEAST
ALLOWING THE PRESSURE GRADIENT TO SLACKEN. WINDS HAVE LARGELY BEEN
JUST BELOW WIND ADVISORY CRITERIA /SUSTAINED OF 30 MPH AND GUSTS OF
45 MPH/ IN THE PAST SEVERAL HOURS. COULD STILL GET A FEW HIGHER
READINGS YET THIS AFTERNOON BUT FEEL THIS WOULD BE MORE LOCALIZED SO
NO NEED FOR ADDITIONAL WIND HEADLINES.
THE SNOW OCCURRING AT THE PRESENT TIME WILL CONTINUE TO SHIFT EAST
THROUGH THIS EVENING AND WILL BE MOSTLY OUT OF THE FORECAST AREA BY
00Z. AFTER 00Z...CHANCES FOR PRECIPITATION WILL BE FOCUSED OVER THE
SOUTHWEST AS THE UPPER LEVEL SYSTEM OVER UTAH KICKS EAST OVERNIGHT.
THAT SYSTEM HAS BEEN TRENDING FURTHER SOUTH OVER THE PAST FEW
DAYS...AND 12Z MODEL RUNS ARE FAIRLY CONSISTENT KEEPING
PRECIPITATION TONIGHT SOUTH OF THE AREA...ACROSS COLORADO AND
KANSAS. DID TREND THE FORECAST DRIER FOR THE EVENING...BUT KEPT
SLIGHT CHANCES FOR THE FAR SOUTHWEST IN CASE OF A SLIGHT SHIFT.
COLDER AIR WILL STAY IN PLACE AS ANOTHER LOW PRESSURE SYSTEM OUT OF
CANADA MOVES INTO THE NORTHERN PLAINS. THIS SYSTEM WILL JUST ENHANCE
THE INFLUENCE OF THE COLDER AIR BY KEEPING IT HERE RATHER THAN
LETTING IT DRIFT EAST. SKIES ARE EXPECTED TO CLEAR OUT BY MONDAY
MORNING...AND WITH THE NEW SNOW...MAY GET SOME RADIATIONAL COOLING
TO HELP COOL THE SURFACE OVERNIGHT. LOWS TONIGHT WERE DROPPED
SLIGHTLY...WITH LOWS IN THE LOW TO MID 20S LIKELY. THEN FOR
MONDAY...THE MODELS ARE SLOW TO MOVE THE COLDER AIRMASS OUT OF THE
AREA...AND ALTHOUGH IT IS MID APRIL...THINK THE SNOW MAY HAVE A
SLIGHT INFLUENCE SO DID DROP HIGHS A FEW DEGREES FOR MONDAY. NOW
LOOKING AT HIGHS IN THE 40S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 PM CDT SUN APR 13 2014
LIGHT SOUTH AND SOUTHWEST WINDS TO DEVELOP MONDAY NIGHT. LOWS WILL
BE SUB FREEZING IN THE LOW TO MID 20S AS LOW DEWPOINTS DICTATE
STRONG COOLING OVERNIGHT.
ON TUESDAY...AN UPSTREAM SHORT WAVE TROUGH DROPS INTO MONTANA AND
IDAHO...TEMPERATURES WILL RECOVERY SIGNIFICANTLY INTO THE LOWER 60S
AS THERMAL RIDGE BUILDS INTO THE CENTRAL HIGH PLAINS.
A COLD FRONT WILL MOVE INTO THE NORTHWEST ZONES TUESDAY NIGHT AS
SCATTERED PRECIPITATION MOVES INTO WYOMING AND THE BLACK HILLS
REGION. LOWS NOT AS COLD IN THE MID 30S. THEN ON WEDNESDAY...A
CHANCE FOR SHOWERS IN NORTH CENTRAL NEBRASKA WITH A COLD FRONT
SWEEPING THE REMAINING FA BY 18Z. THE NAM MODEL IS QUITE A BIT
WARMER WITH H85 TEMPS 4C TO 6C. WILL GO BETWEEN THE COLDER GFS OF 0C
TO -6C. WILL GO NEARER THE NAM SOLUTION WITH MID 50S SOUTHEAST TO
THE MID 40S NORTHWEST. ALSO BREEZY NORTHWEST WINDS. LOWERED POPS
SLIGHTLY WEDNESDAY NIGHT INTO THURSDAY AS SYSTEM LOOKING TO MATURE
ACROSS COLORADO INTO KANSAS AND SERN NEBR. PRECIPITATION TYPE RAIN
OR SNOW WEDNESDAY EVENING...SNOW OVERNIGHT INTO THURSDAY
MORNING...THEN BACK TO RAIN OR SNOW THURSDAY AFTERNOON. HIGHS
THURSDAY CLOSE TO PREVIOUS FORECAST IN THE LOWER 40S.
FOR FRIDAY THROUGH SUNDAY...A DAILY WARMING TREND. AN UPPER RIDGE
IN THE WESTERN CONUS WILL GRADUALLY BUILD EAST INTO THE ROCKIES BY
SUNDAY WITH MUCH MILDER AIR RETURNING TO THE PLAINS. HIGHS IN THE
50S FRIDAY...60S SATURDAY...THEN NEAR 70 SUNDAY. DRY THROUGH THE
PERIOD AS WELL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 623 PM CDT SUN APR 13 2014
AN UPPER LEVEL TROUGH OF LOW PRESSURE WILL TRACK ACROSS THE CENTRAL
ROCKIES INTO SOUTHERN KANSAS OVERNIGHT. LOOK FOR THE THREAT FOR SNOW
IN THE SOUTHEASTERN NEBRASKA PANHANDLE AND FAR SOUTHWESTERN NEBRASKA
TO DIMINISH BY 06Z MONDAY. FOR THE KLBF TERMINAL...EXPECT BROKEN
CIGS RANGING FROM 4000 TO 10000 FT AGL OVERNIGHT TONIGHT INTO MONDAY
MORNING. BROKEN CIGS AROUND 5000 FT AGL ARE EXPECTED MONDAY
AFTERNOON AS A SECONDARY UPPER LEVEL TROUGH DROPS SOUTH FROM THE
DAKOTAS. FOR THE KVTN TERMINAL...BROKEN CIGS AROUND 10000 FT AGL ARE
EXPECTED THROUGH THE EVENING HOURS WITH SOME CLEARING EXPECTED
OVERNIGHT. EXPECT SOME BROKEN CIGS AROUND 5000 FT AGL TO DEVELOP
MONDAY AFTERNOON. WINDS AT BOTH TERMINALS WILL BE FROM THE NORTH OR
NORTHWEST AT 10 TO 20 KTS OVER THE NEXT 24 HOURS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CLB
SHORT TERM...BROOKS
LONG TERM...ROBERG
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
300 PM CDT SAT APR 12 2014
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 300 PM CDT SAT APR 12 2014
CONVECTIVE TRENDS TONIGHT AND PRECIPITATION COVERAGE/TYPE SUNDAY
PRIMARY CONCERN IN SHORT TERM.
WEAK WIND SHIFT/FRONT CONTINUED TO PRESS SEWD INTO THE AFTN
EXTENDING FROM NEAR HARLAN IA TO A LITTLE SE OF OLU AT
20Z...ALTHOUGH BETTER SFC COOLING LAGGED WELL TO THE NORTH. MOST
OF THE AREA IN ADVANCE OF WIND SHIFT HAS HAD ENOUGH OF A SW
COMPONENT TO WIND THAT IT HAD COMBINED WITH MIXING TO LOWER MANY
SFC DWPTS INTO MID 50S OR LOWER...MAIN EXCEPTION THROUGH 20Z FROM
SE CORNER OF NEBR INTO SW IA. THIS HAS HELPED KEEP MIXED LAYER CIN
VALUES STILL FAIRLY HIGH WITH IT WEAKENING IN CNTRL IA TOWARD NEBR
CITY PER SPC MESO PAGE. THUS...WOULD EXPECT FIRST OR AT LEAST
HIGHEST CONVECTION CHANCES WOULD BE IN IA COUNTIES THROUGH SUNSET
WHICH WAS SUPPORTED BY EARLIER THAN 18Z RAP AND ALSO 12Z 4KM WRF.
WITH DECENT...ALTHOUGH NOT EXCEPTIONALLY HIGH...DEEP SHEAR AND ML
CAPE VALUES OF AROUND 2K J/KG....CONDITIONAL SEVERE THREAT REMAINS
IN PLACE WITH LARGE HAIL/WIND RISK EARLY PROBABLY SHIFTING MORE
TOWARD WIND THREAT THIS EVENING. CONVECTIVE DEVELOPMENT FARTHER
SW THIS EVENING OR NORTH OF BOUNDARY OVERNIGHT SOMEWHAT LESS
CERTAIN WITH SOME HINTS BY TWO ABOVE SHORTER TERM MODELS
INDICATING A LULL LATER THIS EVENING/EARLY TONIGHT BEFORE
REDEVELOPMENT TOWARD OR NORTH OF OMAHA/LINCOLN BY 12Z. NE NEBR
COULD REMAIN DRY ALL NIGHT...AND EVEN INTO MID/LATE SUN MORNING
PER NAM...BUT INTRODUCED MODEST POPS TOWARD 12Z INCREASING INTO
CATEGORICAL MOST/ALL AREAS THEN TOWARD MIDDAY.
NAM HAD BACKED OFF SOMEWHAT ON COOLING AIRMASS AS PRECIP FELL NRN
ZONES...EXCEPT FAR NW...AND 12Z GFS/NAM/ECMWF SUGGESTED THAT MUCH
OF THE PRECIP COULD REMAIN LIQUID MUCH OF THE DAY. HOWEVER...KEPT
A R/S MIX IN ACROSS NERN NEBR. SOME CONVECTIVE THREAT COULD
CONTINUE SERN ZONES INTO AT LEAST MIDDAY AS H85 BOUNDARY REMAINS
NEAR SERN NEBR AND WOULD SUSPECT BEST SIGNIFICANT PRECIP CHANCES
WOULD FOCUS TOWARD THAT AREA DUE TO LOW/MID LVL FRONTOGENETICAL
FORCING. HOWEVER...SOME HINT AT A MID LVL FRONTO BAND OF PRECIP
SETTING UP ACROSS THE NORTH THUS AS MENTIONED ABOVE CATEGORICAL
POPS WERE MAINTAINED/INCLUDED ALL AREAS AT LEAST SOME POINT IN THE
DAY. MOST TEMPS STEADY/FALLING BUT IF PRECIP WOULD STAY OUT OF
SERN ZONES UNTIL CLOSER TO MIDDAY COULD SEE A FUTURE NEED FOR A
SLIGHT UPWARD BUMP THERE. WINDS OVER N AND W WILL BE STRONG
ENOUGH TO POSSIBLY WARRANT AN ADVISORY IN LATER FORECASTS...BUT
WILL WAIT UNTIL CONVECTIVE THREAT/PRECIP TRENDS BEFORE THAT PASS
FIRST.
KEPT RAIN/SNOW MIX W/SNOW ON NW FRINGE MENTION IN FORECAST SUN
NIGHT AS COLDER AIR SPILLS SOUTH...ALTHOUGH NOT A CERTAINTY AS GFS
ENDS BULK OF PRECIP MOST AREAS AS SOUNDINGS BECOME COLD ENOUGH TO
SUPPORT SNOW. WITH SOME WIND/CLOUDS PERSISTING...KEPT LOWS ON OR
ABOVE WARMER GUID VALUES SUN NIGHT. WITH SHORTWAVE ENERGY HOLDING
BACK INTO MONDAY...DID UP POPS A LITTLE SERN ZONES SUNDAY NIGHT
BUT KEPT MONDAY DRY FOR NOW. TEMPS LOOK TO BE WELL BELOW NORMAL.
FORECAST LOOKS DRY THEN INTO TUE AND WITH INCREASED MIXING ON
TUESDAY AHEAD OF NEXT TROUGH...TEMPERATURES SHOULD RETURN CLOSER
TO NORMAL.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 300 PM CDT SAT APR 12 2014
KEPT SLGT CHANCE POPS IN WED AFTN FAR NRN ZONES AS 12Z GFS/ECM
BROUGHT NEXT FRONT/TROUGH INTO THAT REGION LATE IN THE DAY.
READINGS SHOULD REBOUND AHEAD OF THIS FRONT...AND IF TRENDS
PERSIST...COULD SEE A NEED FOR FURTHER RAISING IN LATER FORECASTS.
UNCERTAINTIES INCREASE IN THU/FRI PERIOD AS GFS CLOSES OF A COLD
UPPER TROUGH LOOKING DOWNRIGHT NASTY THU NIGHT NERN NEBR. WHILE
ECMWF WAS MORE PROGRESSIVE...IT TOO TRENDED COLDER. THUS WOULD
THINK SOME RAIN/SNOW MIX MENTION WAS STILL WARRANTED WED NGT AND
THURSDAY NIGHT NWRN ZONES AND EVEN EXTENDED MENTION INTO THU
MORNING. COULD FORESEE THIS THREAT BEING SHIFTED SE IF COLD
TRENDS WOULD CONTINUE.
SATURDAY DOES APPEAR A RETURN TO NEAR OR ABOVE NORMAL
TEMPERATURES...AND POPS WERE MENTIONED PER MODEL BLEND.
HOWEVER...MODEL INCONSISTENCY IN THURSDAY AND BEYOND PERIODS LEAD
TO LITTLE CONFIDENCE IN MUCH OF THE EXTENDED.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 140 PM CDT SAT APR 12 2014
A PERIOD OF TRANSITION IS EXPECTED AT ALL THREE SITES AS A COLD
FRONT MOVES SLOWLY SOUTHEAST ACROSS THE AREA. KOMA LOOKS TO HAVE
SOME CHANCE OF SEEING THUNDER AFTER 00Z AS BETTER INSTABILITY
STRETCHES OUT ACROSS IOWA. BEHIND THE FRONT IFR CIGS AND VSBY
DEVELOP AFTER 06Z AS THE COLDER AIR MOVES INTO EASTERN NEBRASKA
COMBINED WITH RAIN AND INCREASING NORTH WINDS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...CHERMOK
LONG TERM...CHERMOK
AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
146 PM CDT SAT APR 12 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 340 AM CDT SAT APR 12 2014
STILL LOTS OF FORECAST CONCERNS IN THE SHORT TERM...TSTM CHANCES
TODAY INTO TONIGHT...POTENTIAL FOR SEVERE STORMS...PCPN TYPE SUNDAY
AND TEMPERATURES THE NEXT FEW DAYS.
UPPER AIR CHARTS FROM LAST EVENING SHOWED THE FOLLOWING. AT 300 MB
ONE JET STREAK OF AROUND 115 KNOTS WAS PUNCHING TOWARD NRN BAJA CA
AND ANOTHER WAS PUNCHING EWD FROM ERN MT. 12 HOUR HEIGHT FALLS OF
AROUND 50 METERS WERE NOTED OVER ERN WA AND SRN BC WITH ANOTHER
SIMILAR AREA OF FALLS OVER CA. SOME LOW LEVEL MOISTURE WAS WORKING
ITS WAY NWD...WITH 850 MB DEWPOINTS AS HIGH AS 11 C AS FAR NORTH AS
NORMAN OK.
SURFACE CHART AT 08Z SHOWED ONE LOW PRESSURE CENTER OVER SRN SD TO
THE NORTHWEST OF KONL AND ANOTHER IN ERN CO. HIGHER DEWPOINTS
WERE MOVING NORTH WITH SOUTHERLY WINDS. FRONTAL BOUNDARY IS STILL
FORECAST TO SLIP SOUTHEAST THROUGH THE AREA AS THE NRN LOW MOVES
ACROSS NRN IA TODAY.
RADAR EARLY THIS MORNING HAS INDICATED SOME ECHOES ACROSS OUR NRN
ZONES BUT AMOUNTS SPOTTY AND LIGHT.
TODAY...DID NOT MAKE MANY CHANGES TO PREVIOUS FCST...BUT DID BUMP
HIGHS UP JUST A BIT SRN ZONES BASED ON LOW LEVEL TRAJECTORIES. WE
STILL EXPECT STORMS TO DEVELOP BY LATE AFTN ALONG THE MISSOURI
RIVER AND INTO SWRN IA. RECENT RUNS OF 13 KM RAP AND SOME OF THE
OTHER HIGH RESOLUTION MODELS SUGGEST THAT. ML CAPE VALUES REACH
AS HIGH AS AROUND 2000 J/KG AND THERE IS ENOUGH SHEAR FOR SOME
STORM ORGANIZATION. STORMS ARE FORECAST TO INCREASE IN COVERAGE
THIS EVENING WITH LOCALLY HEAVY RAIN ALSO POSSIBLE. PRECIPITABLE
WATER VALUES INCREASE TO OVER AN INCH BY THIS EVENING OVER SERN NE
AND SWRN IA.
PCPN COVERAGE WILL INCREASE EVEN MORE TONIGHT AND SUNDAY MORNING
ALONG AND BEHIND THE FRONT IN THE DEFORMATION ZONE WHERE SOME
ELEVATED FRONTOGENESIS IS INDICATED. COULD SEE SOME LOCALIZED
BANDING. MAIN CONVECTION SHOULD SHIFT OUT OF SERN ZONES BY MID
MORNING AS COLD AIR IN THE LOW LEVELS MOVES IN BEHIND THE FRONT.
ALSO...AS THE AIRMASS COOLS IN NERN NE...PCPN WILL MIX WITH AND
PROBABLY CHANCE TO SNOW BASED ON NAM FCST SOUNDINGS. TEMPERATURES
SHOULD BE SLOWLY FALLING ALL DAY SUNDAY. SNOW COULD SPREAD TOWARD
OMAHA AND LINCOLN BY LATE AFTN. FOR NOW...ANY ACCUMULATIONS ARE
EXPECTED TO BE LESS THAN HALF AN INCH. TOTAL RAINFALL AMOUNTS WITH
THIS SYSTEM COULD REACH A QUARTER TO THREE QUARTERS OF AN INCH
MOST AREA WITH SOME SPOTS POSSIBLY OVER AN INCH.
PCPN WILL END SUNDAY NIGHT AS COOL HIGH PRESSURE BUILDS IN FOR
MONDAY. LOWERED HIGHS A BIT TO MAINLY LOWER AND MID 40S.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 340 AM CDT SAT APR 12 2014
STILL LOOK FOR GENERALLY MODERATING TEMPERATURES FOR TUESDAY AND
WEDNESDAY. TUESDAY AND TUESDAY NIGHT SHOULD BE DRY. BUT PCPN
CHANCES RETURN BY WEDNESDAY AFTN IN THE NORTHWEST PART OF NERN NE
THEN FOR THE REST OF THE AREA WEDNESDAY NIGHT INTO FRIDAY. HIGHS
SHOULD BE MOSTLY 50S THURSDAY AND FRIDAY THEN 60S BY SATURDAY.
MODEL ARE NOT IN VERY GOOD AGREEMENT WITH DETAILS LATE NEXT WEEK
SO FORECAST CONFIDENCE DROPS TO ABOUT AVERAGE OR BELOW AVERAGE BY
THEN.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 140 PM CDT SAT APR 12 2014
A PERIOD OF TRANSITION IS EXPECTED AT ALL THREE SITES AS A COLD
FRONT MOVES SLOWLY SOUTHEAST ACROSS THE AREA. KOMA LOOKS TO HAVE
SOME CHANCE OF SEEING THUNDER AFTER 00Z AS BETTER INSTABILITY
STRTCHES OUT ACROSS IOWA. BEHIND THE FRONT IFR CIGS AND VSBY
DEVELOP AFTER 06Z AS THE COLDER AIR MOVES INTO EASTERN NEBRASKA
COMBINED WITH RAIN AND INCREASING NORTH WINDS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
117 PM CDT SAT APR 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 332 AM CDT SAT APR 12 2014
SFC LOW PRESSURE OVER SCNTL SD WILL KICK EAST THIS MORNING AND SEND
A WEAK COLD FRONT THROUGH THE FCST AREA. THE AIR COMING IN IS STILL
MILD AND RUNNING OUT AHEAD OF AN ARCTIC FRONT APPROACHING CALGARY.
WINDS BECOME LIGHT NORTHEAST THIS AFTN AS A NEW LOW PRESSURE CENTER
DEVELOPS ACROSS THE CNTL HIGH PLAINS OF ERN COLO AND EAST TOWARD
KOMA.
THE RESULT IS A VERY SLOW INCREASE IN LOW AND MID LEVEL MOISTURE
ACROSS SRN NEB. THE MODELS ALL SHOW A RAPID INCREASE IN HIGH LEVEL
MOISTURE SUGGESTING A FAIRLY SOLID CANOPY OF CIRRUS DEVELOPS THIS
AFTN. THE TEMPERATURE FORECAST FOLLOWS THE MIDDLE OF THE ROAD FOR
HIGHS IN THE 70S.
BY 00Z TONIGHT K INDICES ARE AROUND 20C OR LESS IN THE RAP MODEL
SUGGESTING TSTM CHANCES THIS AFTN ARE NIL. THIS IS FAIRLY CONSISTENT
WITH THE ECM...SREF AND GFS. NORTHEAST WINDS INCREASE THIS EVENING
PILING UP MOISTURE ON THE HIGH PLAINS BY 06Z AND IT IS BETWEEN 03Z
AND 06Z THAT TSTMS COULD BEGIN APPROACHING THE FCST AREA FROM THE
NEB PANHANDLE. BY THIS TIME THE MOISTURE POOL IS ACROSS THE SRN
PANHANDLE THROUGH INTERSTATE 80 AND AREAS SOUTH. THE SEVERE WEATHER
THREAT WOULD APPEAR SMALL AND IN FACT WE WOULD PROBABLY SEE STORMS
WITH SMALL HAIL.
THE TEMPERATURE FORECAST TONIGHT FOLLOWS A MULTIMODEL APPROACH FOR
LOWS IN THE 30S TO LOWER 40S. THE ARCTIC FRONT SHOULD BE DROPPING
INTO WESTERN NEBRASKA AFTER 06Z TONIGHT WITH A RAIN CHANGEOVER TO
SNOW IN SHERIDAN COUNTY AROUND 09Z WHICH IS CONSISTENT WITH THE GFS
AND 06Z NAM. THE POP AND QPF FORECAST FOLLOWS THE GEM...NAM...GFS
AND ECM. THE SREF WAS THE WETTEST SOLN AND DISCARDED FOR THIS
FORECAST. OVERALL THE BEST RAIN CHANCES ARE ACROSS THE NORTHWEST
LATE TONIGHT AS AN AREA OF STRONG FRONTOGENESIS POOLS MID LEVEL
MOISTURE AND THE ARCTIC AIR COOLS THE LOWER LAYERS CLOSE TO
SATURATION. FARTHER SOUTH...THERE IS TOO MUCH DRY AIR BELOW 700 MB
FOR RAIN. EVEN THE NEXT WETTEST MODEL...THE NAM...WAITS FOR THE
ARCTIC FRONT BEFORE SATURATING BELOW 700 MB. ALAS...THE BEST
FORECAST WILL LIKELY COME FRONT THE RAP MODEL WHICH HAS PERFORMED
THE BEST THIS WINTER AND SPRING.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 332 AM CDT SAT APR 12 2014
COLD FRONT CONTINUES TO PUSH SOUTH THROUGH KANSAS...HEADED FOR THE
SOUTHERN PLAINS AND OUT INTO THE GULF OF MEXICO BY TUESDAY. STRONG
AREA OF FRONTOGENESIS ACROSS NORTHWEST NEBRASKA EARLY SUNDAY
MORNING...WILL MOVE SOUTHEAST ACROSS THE AREA THROUGH THE DAY. THE
FRONTOGENESIS WILL BE IN A WEAKENING STATE AS IT PUSHES
ACROSS...WITH THE PRECIPITATION BAND IN THE FORM OF RAIN AND OR
WET SNOW ASSOCIATED WITH IT ALSO WEAKENING AS IT MOVES NORTHWEST
TO SOUTHEAST. WILL CONTINUE THE LIKELY POPS SUNDAY...BUT DON/T
FEEL COMFORTABLE RISING ANY FURTHER DUE TO THE EXPECTED OVERALL
WEAKENING/DECREASING TREND IN THE PRECIPITATION BAND. BY SUNDAY
EVENING MOST OF THE PRECIPITATION SHOULD HAVE ENDED FOR THE MOST
PART...AS DRY AIR IN THE LOWER AND MID LEVELS VIA A STRONG
NORTHERN STREAM DROP SOUTH/SOUTHEAST INTO THE REGION.
WINDS WILL BE QUITE STRONG SUNDAY INTO SUNDAY EVENING...AS H85
WIND SPEEDS INCREASE TO 50 KTS PLUS. SUSTAINED WINDS AT THE
SURFACE WILL LIKELY BE NEAR 30 MPH WITH GUSTS OVER 45 MPH. CHILLY
CONDITIONS THEN FOR MONDAY AS HIGH PRESSURE BUILD SOUTH INTO THE
PLAINS. TEMPERATURES TUESDAY SHOULD SEE A NICE RECOVERY...WITH
WARMER AIR ALOFT QUICKLY RETURNING BACK NORTHEAST
INTO THE HIGH PLAINS.
LATER IN THE WEEK...QUESTIONS REMAIN REGARDING PRECIPITATION
CHANCES LATER WEDNESDAY THROUGH FRIDAY. THE GFS AND GEFS MEAN
CONTINUE TO INDICATE A POTENT SHORTWAVE DIVING SOUTHEAST THROUGH
THE PACIFIC NORTHWEST INTO THE PLAINS...RESULTING IN DECENT
PRECIPITATION CHANCES. THE ECMWF CONTINUES TO BE MUCH WEAKER WITH
THIS FEATURE...WHILE THE GEM WOULD SUPPORT THE GFS/GEFS. WILL
CONTINUE TO KEEP POPS AT SLIGHT OR LOW CHANCE /30 PERCENT/ FOR
NOW. IT DOES APPEAR THAT ALL MODELS BRING IN MORE COLD AIR...AND
CONFIDENCE IS HIGH THAT THE END OF THE WEEK WILL END ON CHILLY
NOTE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 117 PM CDT SAT APR 12 2014
CONCERNS THROUGH MID DAY SUNDAY ARE WITH INCREASE OF
CLOUDS...WINDS AND PRECIPITATION CHANCES. WINDS WILL STAY
NORTHERLY AND BREEZY THROUGH SUNDAY...AND WILL INCREASE LATE
TONIGHT BEHIND THE PASSAGE OF A COLD FRONT AND STAY GUSTY THROUGH
THE AFTERNOON. EXPECTING SUSTAINED SPEEDS OF 25KTS TO 30KTS WITH
GUSTS TO 40KTS...ESPECIALLY ALONG AND EAST OF A LINE FROM KOGA TO
KVTN. BEHIND THE COLD FRONT CLOUD COVER WILL INCREASE...WITH
CEILINGS LIKELY TO DROP TO MVFR AND POTENTIALLY TO IFR OVER
NORTHERN NEBRASKA SUNDAY MORNING. THE LOWER CATEGORY CEILINGS WILL
BE ACCOMPANIED BY RAIN...CHANGING TO SNOW BY MID MORNING FROM KOGA
TO KANW AND AREAS TO THE NORTHWEST. THE BEST MOISTURE AND LIFT
OCCUR OVER KVTN BETWEEN 14Z AND 17Z...SO DROPPED THE VISIBILITY TO
IFR WITH -SN...ALTHOUGH COULD GET A FEW BURSTS OF MODERATE SNOW
WITH LESSER VISIBILITY.
&&
.FIRE WEATHER...
ISSUED AT 332 AM CDT SAT APR 12 2014
RH FALLS TO AROUND 20 PERCENT ONCE AGAIN THIS AFTERNOON BUT WINDS
ARE VERY LIGHT...JUST 20 TO 25 KT AT H850 IN ALL MODELS. SO FIRE
DANGER IS ELEVATED BUT NOT CRITICAL.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...BROOKS
FIRE WEATHER...CDC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
632 AM CDT SAT APR 12 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 340 AM CDT SAT APR 12 2014
STILL LOTS OF FORECAST CONCERNS IN THE SHORT TERM...TSTM CHANCES
TODAY INTO TONIGHT...POTENTIAL FOR SEVERE STORMS...PCPN TYPE SUNDAY
AND TEMPERATURES THE NEXT FEW DAYS.
UPPER AIR CHARTS FROM LAST EVENING SHOWED THE FOLLOWING. AT 300 MB
ONE JET STREAK OF AROUND 115 KNOTS WAS PUNCHING TOWARD NRN BAJA CA
AND ANOTHER WAS PUNCHING EWD FROM ERN MT. 12 HOUR HEIGHT FALLS OF
AROUND 50 METERS WERE NOTED OVER ERN WA AND SRN BC WITH ANOTHER
SIMILAR AREA OF FALLS OVER CA. SOME LOW LEVEL MOISTURE WAS WORKING
ITS WAY NWD...WITH 850 MB DEWPOINTS AS HIGH AS 11 C AS FAR NORTH AS
NORMAN OK.
SURFACE CHART AT 08Z SHOWED ONE LOW PRESSURE CENTER OVER SRN SD TO
THE NORTHWEST OF KONL AND ANOTHER IN ERN CO. HIGHER DEWPOINTS
WERE MOVING NORTH WITH SOUTHERLY WINDS. FRONTAL BOUNDARY IS STILL
FORECAST TO SLIP SOUTHEAST THROUGH THE AREA AS THE NRN LOW MOVES
ACROSS NRN IA TODAY.
RADAR EARLY THIS MORNING HAS INDICATED SOME ECHOES ACROSS OUR NRN
ZONES BUT AMOUNTS SPOTTY AND LIGHT.
TODAY...DID NOT MAKE MANY CHANGES TO PREVIOUS FCST...BUT DID BUMP
HIGHS UP JUST A BIT SRN ZONES BASED ON LOW LEVEL TRAJECTORIES. WE
STILL EXPECT STORMS TO DEVELOP BY LATE AFTN ALONG THE MISSOURI
RIVER AND INTO SWRN IA. RECENT RUNS OF 13 KM RAP AND SOME OF THE
OTHER HIGH RESOLUTION MODELS SUGGEST THAT. ML CAPE VALUES REACH
AS HIGH AS AROUND 2000 J/KG AND THERE IS ENOUGH SHEAR FOR SOME
STORM ORGANIZATION. STORMS ARE FORECAST TO INCREASE IN COVERAGE
THIS EVENING WITH LOCALLY HEAVY RAIN ALSO POSSIBLE. PRECIPITABLE
WATER VALUES INCREASE TO OVER AN INCH BY THIS EVENING OVER SERN NE
AND SWRN IA.
PCPN COVERAGE WILL INCREASE EVEN MORE TONIGHT AND SUNDAY MORNING
ALONG AND BEHIND THE FRONT IN THE DEFORMATION ZONE WHERE SOME
ELEVATED FRONTOGENESIS IS INDICATED. COULD SEE SOME LOCALIZED
BANDING. MAIN CONVECTION SHOULD SHIFT OUT OF SERN ZONES BY MID
MORNING AS COLD AIR IN THE LOW LEVELS MOVES IN BEHIND THE FRONT.
ALSO...AS THE AIRMASS COOLS IN NERN NE...PCPN WILL MIX WITH AND
PROBABLY CHANCE TO SNOW BASED ON NAM FCST SOUNDINGS. TEMPERATURES
SHOULD BE SLOWLY FALLING ALL DAY SUNDAY. SNOW COULD SPREAD TOWARD
OMAHA AND LINCOLN BY LATE AFTN. FOR NOW...ANY ACCUMULATIONS ARE
EXPECTED TO BE LESS THAN HALF AN INCH. TOTAL RAINFALL AMOUNTS WITH
THIS SYSTEM COULD REACH A QUARTER TO THREE QUARTERS OF AN INCH
MOST AREA WITH SOME SPOTS POSSIBLY OVER AN INCH.
PCPN WILL END SUNDAY NIGHT AS COOL HIGH PRESSURE BUILDS IN FOR
MONDAY. LOWERED HIGHS A BIT TO MAINLY LOWER AND MID 40S.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 340 AM CDT SAT APR 12 2014
STILL LOOK FOR GENERALLY MODERATING TEMPERATURES FOR TUESDAY AND
WEDNESDAY. TUESDAY AND TUESDAY NIGHT SHOULD BE DRY. BUT PCPN
CHANCES RETURN BY WEDNESDAY AFTN IN THE NORTHWEST PART OF NERN NE
THEN FOR THE REST OF THE AREA WEDNESDAY NIGHT INTO FRIDAY. HIGHS
SHOULD BE MOSTLY 50S THURSDAY AND FRIDAY THEN 60S BY SATURDAY.
MODEL ARE NOT IN VERY GOOD AGREEMENT WITH DETAILS LATE NEXT WEEK
SO FORECAST CONFIDENCE DROPS TO ABOUT AVERAGE OR BELOW AVERAGE BY
THEN.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 622 AM CDT SAT APR 12 2014
MOST PRESSING AVN ISSUE IS DETERIORATING CONDITIONS ASSOC WITH
TSRA DEVELOPMENT LATER TONIGHT AT KOMA/KLNK. CONVECTIVE ACTIVITY
WILL REVOLVE AROUND A STATIONARY FRONT EXPECTED TO EXTEND FROM
CNTRL KS TO CNTRL IA BY MIDNIGHT. EXPECT TSRA TO INCREASE IN
AREAL COVERAGE THEN BTWN 06Z-12Z SUN. AS FOR KOFK...APPEARS THAT
CHANCES ARE RATHER LOW THAT ANY TSRA ACTIVITY WILL EXPAND FAR
ENOUGH NORTH TO AFFECT KOFK. IS PROBABLE THOUGH KOFK WILL SEE MVFR
CIGS SETTLE IN BY EARLY SUN MORNING.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...DEE
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
359 AM CDT SAT APR 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 332 AM CDT SAT APR 12 2014
SFC LOW PRESSURE OVER SCNTL SD WILL KICK EAST THIS MORNING AND SEND
A WEAK COLD FRONT THROUGH THE FCST AREA. THE AIR COMING IN IS STILL
MILD AND RUNNING OUT AHEAD OF AN ARCTIC FRONT APPROACHING CALGARY.
WINDS BECOME LIGHT NORTHEAST THIS AFTN AS A NEW LOW PRESSURE CENTER
DEVELOPS ACROSS THE CNTL HIGH PLAINS OF ERN COLO AND EAST TOWARD
KOMA.
THE RESULT IS A VERY SLOW INCREASE IN LOW AND MID LEVEL MOISTURE
ACROSS SRN NEB. THE MODELS ALL SHOW A RAPID INCREASE IN HIGH LEVEL
MOISTURE SUGGESTING A FAIRLY SOLID CANOPY OF CIRRUS DEVELOPS THIS
AFTN. THE TEMPERATURE FORECAST FOLLOWS THE MIDDLE OF THE ROAD FOR
HIGHS IN THE 70S.
BY 00Z TONIGHT K INDICES ARE AROUND 20C OR LESS IN THE RAP MODEL
SUGGESTING TSTM CHANCES THIS AFTN ARE NIL. THIS IS FAIRLY CONSISTENT
WITH THE ECM...SREF AND GFS. NORTHEAST WINDS INCREASE THIS EVENING
PILING UP MOISTURE ON THE HIGH PLAINS BY 06Z AND IT IS BETWEEN 03Z
AND 06Z THAT TSTMS COULD BEGIN APPROACHING THE FCST AREA FROM THE
NEB PANHANDLE. BY THIS TIME THE MOISTURE POOL IS ACROSS THE SRN
PANHANDLE THROUGH INTERSTATE 80 AND AREAS SOUTH. THE SEVERE WEATHER
THREAT WOULD APPEAR SMALL AND IN FACT WE WOULD PROBABLY SEE STORMS
WITH SMALL HAIL.
THE TEMPERATURE FORECAST TONIGHT FOLLOWS A MULTIMODEL APPROACH FOR
LOWS IN THE 30S TO LOWER 40S. THE ARCTIC FRONT SHOULD BE DROPPING
INTO WESTERN NEBRASKA AFTER 06Z TONIGHT WITH A RAIN CHANGEOVER TO
SNOW IN SHERIDAN COUNTY AROUND 09Z WHICH IS CONSISTENT WITH THE GFS
AND 06Z NAM. THE POP AND QPF FORECAST FOLLOWS THE GEM...NAM...GFS
AND ECM. THE SREF WAS THE WETTEST SOLN AND DISCARDED FOR THIS
FORECAST. OVERALL THE BEST RAIN CHANCES ARE ACROSS THE NORTHWEST
LATE TONIGHT AS AN AREA OF STRONG FRONTOGENESIS POOLS MID LEVEL
MOISTURE AND THE ARCTIC AIR COOLS THE LOWER LAYERS CLOSE TO
SATURATION. FARTHER SOUTH...THERE IS TOO MUCH DRY AIR BELOW 700 MB
FOR RAIN. EVEN THE NEXT WETTEST MODEL...THE NAM...WAITS FOR THE
ARCTIC FRONT BEFORE SATURATING BELOW 700 MB. ALAS...THE BEST
FORECAST WILL LIKELY COME FRONT THE RAP MODEL WHICH HAS PERFORMED
THE BEST THIS WINTER AND SPRING.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 332 AM CDT SAT APR 12 2014
COLD FRONT CONTINUES TO PUSH SOUTH THROUGH KANSAS...HEADED FOR THE
SOUTHERN PLAINS AND OUT INTO THE GULF OF MEXICO BY TUESDAY. STRONG
AREA OF FRONTOGENESIS ACROSS NORTHWEST NEBRASKA EARLY SUNDAY
MORNING...WILL MOVE SOUTHEAST ACROSS THE AREA THROUGH THE DAY. THE
FRONTOGENESIS WILL BE IN A WEAKENING STATE AS IT PUSHES
ACROSS...WITH THE PRECIPITATION BAND IN THE FORM OF RAIN AND OR
WET SNOW ASSOCIATED WITH IT ALSO WEAKENING AS IT MOVES NORTHWEST
TO SOUTHEAST. WILL CONTINUE THE LIKELY POPS SUNDAY...BUT DON/T
FEEL COMFORTABLE RISING ANY FURTHER DUE TO THE EXPECTED OVERALL
WEAKENING/DECREASING TREND IN THE PRECIPITATION BAND. BY SUNDAY
EVENING MOST OF THE PRECIPITATION SHOULD HAVE ENDED FOR THE MOST
PART...AS DRY AIR IN THE LOWER AND MID LEVELS VIA A STRONG
NORTHERN STREAM DROP SOUTH/SOUTHEAST INTO THE REGION.
WINDS WILL BE QUITE STRONG SUNDAY INTO SUNDAY EVENING...AS H85
WIND SPEEDS INCREASE TO 50 KTS PLUS. SUSTAINED WINDS AT THE
SURFACE WILL LIKELY BE NEAR 30 MPH WITH GUSTS OVER 45 MPH. CHILLY
CONDITIONS THEN FOR MONDAY AS HIGH PRESSURE BUILD SOUTH INTO THE
PLAINS. TEMPERATURES TUESDAY SHOULD SEE A NICE RECOVERY...WITH
WARMER AIR ALOFT QUICKLY RETURNING BACK NORTHEAST
INTO THE HIGH PLAINS.
LATER IN THE WEEK...QUESTIONS REMAIN REGARDING PRECIPITATION
CHANCES LATER WEDNESDAY THROUGH FRIDAY. THE GFS AND GEFS MEAN
CONTINUE TO INDICATE A POTENT SHORTWAVE DIVING SOUTHEAST THROUGH
THE PACIFIC NORTHWEST INTO THE PLAINS...RESULTING IN DECENT
PRECIPITATION CHANCES. THE ECMWF CONTINUES TO BE MUCH WEAKER WITH
THIS FEATURE...WHILE THE GEM WOULD SUPPORT THE GFS/GEFS. WILL
CONTINUE TO KEEP POPS AT SLIGHT OR LOW CHANCE /30 PERCENT/ FOR
NOW. IT DOES APPEAR THAT ALL MODELS BRING IN MORE COLD AIR...AND
CONFIDENCE IS HIGH THAT THE END OF THE WEEK WILL END ON CHILLY
NOTE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1224 AM CDT SAT APR 12 2014
CEILING AND VISIBILITY WILL BE ABOVE VISUAL THRESHOLDS THROUGH LATE
SATURDAY EVENING. IN THE SOUTHWEST...WIND WILL START OUT 160-200 AT
12-14G19-22KT AND SWING AROUND TO 240-280 AT 12-14KT BY 09Z. THEN...
THROUGHOUT THE AREA...WIND WILL GRADUALLY BECOME NORTH TO NORTHEAST
AS A FRONT MAKES ITS WAY INTO EAST CENTRAL AND SOUTH CENTRAL
NEBRASKA.
&&
.FIRE WEATHER...
ISSUED AT 332 AM CDT SAT APR 12 2014
RH FALLS TO AROUND 20 PERCENT ONCE AGAIN THIS AFTERNOON BUT WINDS
ARE VERY LIGHT...JUST 20 TO 25 KT AT H850 IN ALL MODELS. SO FIRE
DANGER IS ELEVATED BUT NOT CRITICAL.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CDC
FIRE WEATHER...CDC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
340 AM CDT SAT APR 12 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 340 AM CDT SAT APR 12 2014
STILL LOTS OF FORECAST CONCERNS IN THE SHORT TERM...TSTM CHANCES
TODAY INTO TONIGHT...POTENTIAL FOR SEVERE STORMS...PCPN TYPE SUNDAY
AND TEMPERATURES THE NEXT FEW DAYS.
UPPER AIR CHARTS FROM LAST EVENING SHOWED THE FOLLOWING. AT 300 MB
ONE JET STREAK OF AROUND 115 KNOTS WAS PUNCHING TOWARD NRN BAJA CA
AND ANOTHER WAS PUNCHING EWD FROM ERN MT. 12 HOUR HEIGHT FALLS OF
AROUND 50 METERS WERE NOTED OVER ERN WA AND SRN BC WITH ANOTHER
SIMILAR AREA OF FALLS OVER CA. SOME LOW LEVEL MOISTURE WAS WORKING
ITS WAY NWD...WITH 850 MB DEWPOINTS AS HIGH AS 11 C AS FAR NORTH AS
NORMAN OK.
SURFACE CHART AT 08Z SHOWED ONE LOW PRESSURE CENTER OVER SRN SD TO
THE NORTHWEST OF KONL AND ANOTHER IN ERN CO. HIGHER DEWPOINTS
WERE MOVING NORTH WITH SOUTHERLY WINDS. FRONTAL BOUNDARY IS STILL
FORECAST TO SLIP SOUTHEAST THROUGH THE AREA AS THE NRN LOW MOVES
ACROSS NRN IA TODAY.
RADAR EARLY THIS MORNING HAS INDICATED SOME ECHOES ACROSS OUR NRN
ZONES BUT AMOUNTS SPOTTY AND LIGHT.
TODAY...DID NOT MAKE MANY CHANGES TO PREVIOUS FCST...BUT DID BUMP
HIGHS UP JUST A BIT SRN ZONES BASED ON LOW LEVEL TRAJECTORIES. WE
STILL EXPECT STORMS TO DEVELOP BY LATE AFTN ALONG THE MISSOURI
RIVER AND INTO SWRN IA. RECENT RUNS OF 13 KM RAP AND SOME OF THE
OTHER HIGH RESOLUTION MODELS SUGGEST THAT. ML CAPE VALUES REACH
AS HIGH AS AROUND 2000 J/KG AND THERE IS ENOUGH SHEAR FOR SOME
STORM ORGANIZATION. STORMS ARE FORECAST TO INCREASE IN COVERAGE
THIS EVENING WITH LOCALLY HEAVY RAIN ALSO POSSIBLE. PRECIPITABLE
WATER VALUES INCREASE TO OVER AN INCH BY THIS EVENING OVER SERN NE
AND SWRN IA.
PCPN COVERAGE WILL INCREASE EVEN MORE TONIGHT AND SUNDAY MORNING
ALONG AND BEHIND THE FRONT IN THE DEFORMATION ZONE WHERE SOME
ELEVATED FRONTOGENESIS IS INDICATED. COULD SEE SOME LOCALIZED
BANDING. MAIN CONVECTION SHOULD SHIFT OUT OF SERN ZONES BY MID
MORNING AS COLD AIR IN THE LOW LEVELS MOVES IN BEHIND THE FRONT.
ALSO...AS THE AIRMASS COOLS IN NERN NE...PCPN WILL MIX WITH AND
PROBABLY CHANCE TO SNOW BASED ON NAM FCST SOUNDINGS. TEMPERATURES
SHOULD BE SLOWLY FALLING ALL DAY SUNDAY. SNOW COULD SPREAD TOWARD
OMAHA AND LINCOLN BY LATE AFTN. FOR NOW...ANY ACCUMULATIONS ARE
EXPECTED TO BE LESS THAN HALF AN INCH. TOTAL RAINFALL AMOUNTS WITH
THIS SYSTEM COULD REACH A QUARTER TO THREE QUARTERS OF AN INCH
MOST AREA WITH SOME SPOTS POSSIBLY OVER AN INCH.
PCPN WILL END SUNDAY NIGHT AS COOL HIGH PRESSURE BUILDS IN FOR
MONDAY. LOWERED HIGHS A BIT TO MAINLY LOWER AND MID 40S.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 340 AM CDT SAT APR 12 2014
STILL LOOK FOR GENERALLY MODERATING TEMPERATURES FOR TUESDAY AND
WEDNESDAY. TUESDAY AND TUESDAY NIGHT SHOULD BE DRY. BUT PCPN
CHANCES RETURN BY WEDNESDAY AFTN IN THE NORTHWEST PART OF NERN NE
THEN FOR THE REST OF THE AREA WEDNESDAY NIGHT INTO FRIDAY. HIGHS
SHOULD BE MOSTLY 50S THURSDAY AND FRIDAY THEN 60S BY SATURDAY.
MODEL ARE NOT IN VERY GOOD AGREEMENT WITH DETAILS LATE NEXT WEEK
SO FORECAST CONFIDENCE DROPS TO ABOUT AVERAGE OR BELOW AVERAGE BY
THEN.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1149 PM CDT FRI APR 11 2014
MVFR CIGS ARE LIKELY TO DEVELOP BETWEEN 12Z AND 18Z AT KLNK AND
KOMA AS LOW LEVEL MOISTURE WORKS NORTH FROM KANSAS AND OKLAHOMA
OVERNIGHT. A COLD FRONT DROPPING SOUTH THROUGH EASTERN NEBRASKA
WILL PASS KOFK BY 18Z...SWITCHING WINDS TO THE NORTH THERE WITH
SPEEDS NEAR 12KT. THE FRONT WILL ONLY SLOWLY DRIFT SOUTH THROUGH
THE AFTERNOON...AND LIMP THROUGH KLNK AND KOMA AREAS BETWEEN 00Z
AND 06Z. SCATTERED SHOWERS OR THUNDERSTORMS ARE POSSIBLE ALONG THE
FRONT AFTER 21Z...BUT IT APPEARS MOST ACTIVITY WILL DEVELOP SOUTH
OF KLNK AND KOMA TAF SITES AND REMAIN SOUTH THROUGH THE END OF THE
TAF PERIOD.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...DERGAN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1014 PM EDT SUN APR 13 2014
.SYNOPSIS...
MILD AND DRY OVERNIGHT...AND STILL WARM MONDAY. MEANWHILE...LOW
PRESSURE OVER THE CENTRAL U.S. WILL MOVE NORTHEAST AND BRING
SHOWERS TO AREA LATER MONDAY INTO MONDAY NIGHT. ON TUESDAY...A
STRONG COLD FRONT WILL PASS THROUGH. LOCALLY HEAVY RAIN WILL BE
POSSIBLE AHEAD OF THE COLD FRONT...WITH THE POTENTIAL FOR
ACCUMULATING SNOWS BEHIND IT ACROSS CENTRAL NEW YORK. HIGH
PRESSURE WILL BRING A RETURN TO FAIR WEATHER ON WEDNESDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
1015 PM UPDATE...
ELEVATED CONVECTION IS OCCURRING NORTH OF THE SURFACE BOUNDARY
AROUND THE SAINT LAWRENCE SEAWAY...SO AS EXPECTED WE ARE STAYING
DRY TONIGHT. WINDS HAVE QUICKLY DECOUPLED AND SOME GRADUAL DROPOFF
IN TEMPERATURES IS OCCURRING. VERY MILD REGARDLESS...WITH LOWS
EXPECTED TO RANGE FROM THE MID 50S TO NEAR 60.
WITH A GOOD AMOUNT OF SUNSHINE EARLIER...SINCE THE HIGH THIN CLOUDS
ERADICATED MORE THAN EXPECTED...THE LOW 20S CELSIUS TEMPERATURES
AT 925MB /AS HAD BEEN SUGGESTED BY RUC MODEL/ WERE ABLE TO FULLY
REALIZE THEIR MIX-DOWN TEMPERATURES OF LOW 80S IN MANY
LOCATIONS...THE WARMEST READINGS IN 6 MONTHS. BINGHAMTON AIRPORT
DAILY RECORD HIGH IS 80 DEGREES SET IN 1977...AND IT TURNED OUT
JUST 1 DEGREE SHORT OF IT TODAY. SYRACUSE AND AVOCA ALSO JUST A
FEW DEGREES SHY OF DAILY RECORDS.
PREVIOUS DISCUSSION...
VERY MILD TEMPS TDA WITH WARM SWLY FLOW. MAY SEE AN ISOLATED -SHRA
ACRS NRN ONEIDA LATE TDA OR THIS EVNG OTRW A DRY FCST. VERY MILD
MINS TNGT.
NXT SYSTEM APRCHS TMRW. A FEW MDLS HINT AT SOME CONVECTION ALONG A
PRE-FNTL TROF OVER CNTRL NY ARND MID DAY. IN ANY EVENT...INCRSNG
CHCS FOR SHRA TMRW AFTN WITH MAXES GETTING BACK INTO THE 70S MOST
AREAS. TEMPS MAY FALL DURING THE AFTN WRN ZONES AS CLDS AND SCT
-SHRA MOVE IN. GUSTY SSW WINDS CONTINUE ON MON.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
VERY COMPLEX STORM SYSTEM WITH SHARP BAROCLINIC ZONE/ANAFRONT
MOVS THRU ON TUE WITH WEAK SFC WAVES RIDING NE ALONG IT.
TIMING OF THIS FNT ON TUE WILL BE CRITICAL TO THE FCST
W/RESPECT TO CHGOVER AND +RA POTNL IN THE EAST. IN GNRL 12Z RUNS
ARE SUGGESTING THAT THE TRANSITION ZONE IS BASICALLY THRU THE CWA
BY 00Z WED...AND NAM/GFS SFC INDICATE RAPIDLY FALLING SNOW LVLS WITH THE
FNT ON TUE.
BOTTOM LINE IS THAT THERE IS ALOT OF UNCERTAINTY WITH THIS
STORM...BUT TREND HAS BEEN FOR A SLIGHTLY QUICKER TIMING. WE COULD
SEE PL IN THE TRANSITION ZONE BUT FOR NOW WILL JUST PLAY IT AS RAIN
CHANGING TO SNOW. GIVEN A COUPLE OF VERY WARM DAYS THINK ICE POTNL
FROM NAM PROFILES IS OVERDONE. WE DID LIKE THE WWD SNOW ACCUMS
WITH POTNL FOR GNRLY 2-4 INCHES ON TUE AFTN/EVNG ACRS PORTIONS OF
CNTRL NY.
MAYBE A FEW FLURRIES SE OF LAKE ONTARIO ON TUE NGT...WITH LAKE
CLDS LIKELY SE OF LAKE ONTARIO ON WED MRNG IN NWLY FLOW. MUCH
COOLER WITH MAXES ONLY U30S TO L40S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
MEDIUM RANGE MODELS START OUT IN GOOD AGREEMENT EARLY IN THE
EXTENDED PERIOD THEN DIVERGE BY NEXT WEEKEND.
INITIALLY SFC HIGH PRES OVER NRN NEW ENGLAND AND NOVA SCOTIA WILL
BRING FAIR AND COOL WEATHER TO THE AREA WITH LOWS WED NIGHT IN THE
MID TO UPPER 20S FOLLOWED BY UPPER 20S TO MID 30S ON THURSDAY
NIGHT. MAXES BOTH THURSDAY AND FRIDAY WILL RANGE IN THE 50S WITH
SOME MODIFICATION ON FRIDAY.
FRIDAY NIGHT THROUGH SUNDAY THE OPERATIONAL GFS TAKES A SFC LOW
IN THE TN VALLEY AND TRACKS IT NORTHEAST ACROSS OUR VCNTY THEN INTO
EASTERN CANADA BY SUNDAY. A WET SCENARIO FOLLOWED BY WRAP AROUND
MOISTURE SATURDAY NIGHT INTO SUNDAY. THE ECMWF PLACES THIS FEATURE
FARTHER SOUTH AND WEAKER THEN MOVES IT OFF THE MID ATLANTIC COAST
KEEPING THE REGION BASICALLY DRY. FOLLOWED HPC GUIDANCE WHICH
KEEPS THE SYSTEM TO OUR SOUTH BUT WILL INCLUDE CHC POPS FROM
FRIDAY NIGHT THROUGH SATURDAY NIGHT FOR RAIN SHOWERS.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
00Z UPDATE...
VFR CONDITIONS GENERALLY EXPECTED THROUGH 00Z TUESDAY...BUT
SCATTERED SHOWERS AND PERHAPS ISOLATED THUNDERSTORMS COULD BE
MOVING INTO THE WESTERN TERMINALS /KSYR-KITH-KELM AND MAYBE KRME/
21Z MON-00Z TUE. THIS WILL BE WITH INCREASING MOISTURE AND
INSTABILITY AHEAD OF AN APPROACHING COLD FRONT...WHICH WILL NOT
PASS UNTIL TUESDAY. WINDS DECOUPLING AND DIMINISHING THIS EVENING NEAR
THE SURFACE...YET STILL STRONG FROM THE SSW AS A 40-50 KT JET
DEVELOPS AT 1500-2000 FT AGL...RESULTING IN LLWS CONDITIONS
OVERNIGHT. LLWS THEN BECOMES A NON-ISSUE SHORTLY AFTER 12Z AS WINDS
MANAGE TO MIX DOWN BETTER TO THE SURFACE WITH DAYTIME HEATING.
DURING THE DAY MONDAY...SURFACE WIND SUSTAINED MID TEENS WITH
GUSTS IN 25-30 KT RANGE...FROM SSW DIRECTION.
OUTLOOK...
MON NGT-TUE...RESTRICTIONS IN SCATTERED RAIN SHOWERS AND ISOLATED
THUNDER MONDAY NIGHT TO TUESDAY MORNING...THEN RAIN CHANGING TO
SNOW TUE AFTERNOON-EVENING.
TUE NGT...RESTRICTIONS POSSIBLE IN SCATTERED SNOW SHOWERS.
WED-THU-FRI...VFR.
&&
.FIRE WEATHER...
1015 PM SUNDAY UPDATE...
CONDITIONS APPROACHED CRITICAL VALUES SUNDAY AFTERNOON BUT WINDS
HAVE BACKED OFF CONSIDERABLY THIS EVENING ALONG WITH RECOVERING
RELATIVE HUMIDITY ALREADY IN THE 40S-50S PCT RANGE AT 10 PM.
FAIRLY WARM WITH STOUT SOUTH-SOUTHWEST WINDS AGAIN MONDAY...BUT
WITH HIGHER HUMIDITY VALUES AS MOISTURE INCREASES AHEAD OF
APPROACHING COLD FRONT. MINIMUM HUMIDITY VALUES MONDAY...VERSUS
WHAT WE JUST HAD SUNDAY AFTERNOON...WILL BE A GOOD 15 TO 25
PERCENT HIGHER. RAIN CHANCES INCREASING LATE MONDAY THROUGH MONDAY
NIGHT...LEADING TO A SOLID WETTING RAIN TUESDAY WITH FALLING
TEMPERATURES. EVEN SOME CHANGEOVER TO SNOW TUESDAY AFTERNOON-
EVENING /ESPECIALLY CENTRAL NY/.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...
LONG TERM...RRM
AVIATION...MDP
FIRE WEATHER...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
743 PM EDT SUN APR 13 2014
.SYNOPSIS...
LOW PRESSURE OVER THE CENTRAL U.S. WILL MOVE NORTHEAST AND BRING
SHOWERS TO AREA LATER MONDAY INTO MONDAY NIGHT. ON TUESDAY...A
STRONG COLD FRONT WILL PASS THROUGH. LOCALLY HEAVY RAIN WILL BE
POSSIBLE AHEAD OF THE COLD FRONT...WITH THE POTENTIAL FOR
ACCUMULATING SNOWS BEHIND IT ACROSS CENTRAL NEW YORK. HIGH
PRESSURE WILL BRING A RETURN TO FAIR WEATHER ON WEDNESDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
635 PM UPDATE...
REMOVED SLIGHT CHANCE OF SHOWER FROM ONEIDA COUNTY THIS EVENING
WITH BOUNDARY LAYER BEING TOO DRY TO REALIZE THE SPOTTY QPF OF
EARLIER MODELS.
WITH A GOOD AMOUNT OF SUNSHINE SINCE THE HIGH THIN CLOUDS
ERADICATED MORE THAN EXPECTED...THE LOW 20S CELSIUS TEMPERATURES
AT 925MB /AS HAD BEEN SUGGESTED BY RUC MODEL/ WERE ABLE TO FULLY
REALIZE THEIR MIX-DOWN TEMPERATURES OF LOW 80S IN MANY
LOCATIONS...THE WARMEST READINGS IN 6 MONTHS. BINGHAMTON AIRPORT
DAILY RECORD HIGH IS 80 DEGREES SET IN 1977...AND IT TURNED OUT
JUST 1 DEGREE SHORT OF IT TODAY. SYRACUSE AND AVOCA ALSO JUST A
FEW DEGREES SHY OF DAILY RECORDS.
PREVIOUS DISCUSSION...
VERY MILD TEMPS TDA WITH WARM SWLY FLOW. MAY SEE AN ISOLATED -SHRA
ACRS NRN ONEIDA LATE TDA OR THIS EVNG OTRW A DRY FCST. VERY MILD
MINS TNGT.
NXT SYSTEM APRCHS TMRW. A FEW MDLS HINT AT SOME CONVECTION ALONG A
PRE-FNTL TROF OVER CNTRL NY ARND MID DAY. IN ANY EVENT...INCRSNG
CHCS FOR SHRA TMRW AFTN WITH MAXES GETTING BACK INTO THE 70S MOST
AREAS. TEMPS MAY FALL DURING THE AFTN WRN ZONES AS CLDS AND SCT
-SHRA MOVE IN. GUSTY SSW WINDS CONTINUE ON MON.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
VERY COMPLEX STORM SYSTEM WITH SHARP BAROCLINIC ZONE/ANAFRONT
MOVS THRU ON TUE WITH WEAK SFC WAVES RIDING NE ALONG IT.
TIMING OF THIS FNT ON TUE WILL BE CRITICAL TO THE FCST
W/RESPECT TO CHGOVER AND +RA POTNL IN THE EAST. IN GNRL 12Z RUNS
ARE SUGGESTING THAT THE TRANSITION ZONE IS BASICALLY THRU THE CWA
BY 00Z WED...AND NAM/GFS SFC INDICATE RAPIDLY FALLING SNOW LVLS WITH THE
FNT ON TUE.
BOTTOM LINE IS THAT THERE IS ALOT OF UNCERTAINTY WITH THIS
STORM...BUT TREND HAS BEEN FOR A SLIGHTLY QUICKER TIMING. WE COULD
SEE PL IN THE TRANSITION ZONE BUT FOR NOW WILL JUST PLAY IT AS RAIN
CHANGING TO SNOW. GIVEN A COUPLE OF VERY WARM DAYS THINK ICE POTNL
FROM NAM PROFILES IS OVERDONE. WE DID LIKE THE WWD SNOW ACCUMS
WITH POTNL FOR GNRLY 2-4 INCHES ON TUE AFTN/EVNG ACRS PORTIONS OF
CNTRL NY.
MAYBE A FEW FLURRIES SE OF LAKE ONTARIO ON TUE NGT...WITH LAKE
CLDS LIKELY SE OF LAKE ONTARIO ON WED MRNG IN NWLY FLOW. MUCH
COOLER WITH MAXES ONLY U30S TO L40S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
MEDIUM RANGE MODELS START OUT IN GOOD AGREEMENT EARLY IN THE
EXTENDED PERIOD THEN DIVERGE BY NEXT WEEKEND.
INITIALLY SFC HIGH PRES OVER NRN NEW ENGLAND AND NOVA SCOTIA WILL
BRING FAIR AND COOL WEATHER TO THE AREA WITH LOWS WED NIGHT IN THE
MID TO UPPER 20S FOLLOWED BY UPPER 20S TO MID 30S ON THURSDAY
NIGHT. MAXES BOTH THURSDAY AND FRIDAY WILL RANGE IN THE 50S WITH
SOME MODIFICATION ON FRIDAY.
FRIDAY NIGHT THROUGH SUNDAY THE OPERATIONAL GFS TAKES A SFC LOW
IN THE TN VALLEY AND TRACKS IT NORTHEAST ACROSS OUR VCNTY THEN INTO
EASTERN CANADA BY SUNDAY. A WET SCENARIO FOLLOWED BY WRAP AROUND
MOISTURE SATURDAY NIGHT INTO SUNDAY. THE ECMWF PLACES THIS FEATURE
FARTHER SOUTH AND WEAKER THEN MOVES IT OFF THE MID ATLANTIC COAST
KEEPING THE REGION BASICALLY DRY. FOLLOWED HPC GUIDANCE WHICH
KEEPS THE SYSTEM TO OUR SOUTH BUT WILL INCLUDE CHC POPS FROM
FRIDAY NIGHT THROUGH SATURDAY NIGHT FOR RAIN SHOWERS.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
00Z UPDATE...
VFR CONDITIONS GENERALLY EXPECTED THROUGH 00Z TUESDAY...BUT
SCATTERED SHOWERS AND PERHAPS ISOLATED THUNDERSTORMS COULD BE
MOVING INTO THE WESTERN TERMINALS /KSYR-KITH-KELM AND MAYBE KRME/
21Z MON-00Z TUE. THIS WILL BE WITH INCREASING MOISTURE AND
INSTABILITY AHEAD OF AN APPROACHING COLD FRONT...WHICH WILL NOT
PASS UNTIL TUESDAY. WINDS DECOUPLING AND DIMINISHING THIS EVENING NEAR
THE SURFACE...YET STILL STRONG FROM THE SSW AS A 40-50 KT JET
DEVELOPS AT 1500-2000 FT AGL...RESULTING IN LLWS CONDITIONS
OVERNIGHT. LLWS THEN BECOMES A NON-ISSUE SHORTLY AFTER 12Z AS WINDS
MANAGE TO MIX DOWN BETTER TO THE SURFACE WITH DAYTIME HEATING.
DURING THE DAY MONDAY...SURFACE WIND SUSTAINED MID TEENS WITH
GUSTS IN 25-30 KT RANGE...FROM SSW DIRECTION.
OUTLOOK...
MON NGT-TUE...RESTRICTIONS IN SCATTERED RAIN SHOWERS AND ISOLATED
THUNDER MONDAY NIGHT TO TUESDAY MORNING...THEN RAIN CHANGING TO
SNOW TUE AFTERNOON-EVENING.
TUE NGT...RESTRICTIONS POSSIBLE IN SCATTERED SNOW SHOWERS.
WED-THU-FRI...VFR.
&&
.FIRE WEATHER...
635 PM SUNDAY UPDATE...
CONDITIONS APPROACHED CRITICAL VALUES THIS AFTERNOON /SUNDAY/ BUT
WINDS WILL CONTINUE TO BACK OFF THIS EVENING ALONG WITH GRADUALLY
RECOVERING RELATIVE HUMIDITY. FAIRLY WARM WITH STOUT SOUTH-
SOUTHWEST WINDS AGAIN MONDAY...BUT WITH HIGHER HUMIDITY VALUES AS
MOISTURE INCREASES AHEAD OF APPROACHING COLD FRONT. MINIMUM
HUMIDITY VALUES MONDAY...VERSUS WHAT WE JUST HAD THIS SUNDAY
AFTERNOON...WILL BE A GOOD 15 TO 25 PERCENT HIGHER. RAIN CHANCES
INCREASING LATE MONDAY THROUGH MONDAY NIGHT...LEADING TO A SOLID
WETTING RAIN TUESDAY WITH FALLING TEMPERATURES. EVEN SOME
CHANGEOVER TO SNOW TUESDAY AFTERNOON- EVENING /ESPECIALLY CENTRAL
NY/.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...
LONG TERM...RRM
AVIATION...MDP
FIRE WEATHER...MDP
AREA FORECAST DISCUSSION
NWS BUFFALO NY
347 PM EDT SAT APR 12 2014
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTHEAST ACROSS THE REGION TONIGHT WITH A
SOME SHOWERS AND POSSIBLY A THUNDERSTORM. THIS FRONT WILL USHER IN
THE WARMEST AIR OF THE SPRING SO FAR SUNDAY AND MONDAY WITH
TEMPERATURES SOARING WELL INTO THE 70S. A STRONG COLD FRONT WILL
SLOWLY CROSS THE REGION LATE MONDAY THROUGH TUESDAY WITH PERIODS OF
RAIN AND POSSIBLY A FEW THUNDERSTORMS. THE RAIN MAY END AS A PERIOD
OF WET SNOW ON TUESDAY AS MUCH COLDER AIR FILTERS INTO THE REGION.
&&
.NEAR TERM /THROUGH SUNDAY/...
THROUGH THIS EVENING...EXPECT WARM TEMPERATURES INLAND WHILE THE
LAKE BREEZE GRADUALLY PROGRESSES FURTHER INLAND. HIGH CLOUDS
ASSOCIATED WITH THUNDERSTORMS ACROSS MICHIGAN WILL QUICKLY SPREAD
FROM WEST TO EAST.
AN AREA OF SHOWERS AND THUNDERSTORMS ALONG A WARM FRONT WILL SPREAD
EASTWARD ALONG THE BOUNDARY OVERNIGHT...WITH INSTABILITY BECOMING
INCREASINGLY ELEVATED. A CONSENSUS OF GUIDANCE (NAM/RGEM/SREF/GFS)
BRING A 50 KT LLJ ACROSS THE REGION...WITH THE STEADIEST LIFT FROM
MID-LEVEL WARM AIR ADVECTION NORTH OF LAKE ONTARIO. MODEL CONSENSUS
SUPPORTS HIGH CONFIDENCE IN PRECIPITATION NORTH OF WATERTOWN.
CONFIDENCE DIMINISHES JUST SOUTH OF THIS...WITH MORE HIT OR MISS
SHOWERS EXPECTED. SOUTHERN PORTIONS OF THE CWA ARE LIKELY TO SEE A
DRY FRONTAL PASSAGE. THE HRRR AND TO A LESSER EXTENT 12Z NAM/RGEM
GUIDANCE BRING A CLUSTER OF SHOWERS ACROSS THE NIAGARA FRONTIER
AROUND MIDNIGHT...WHICH IS FEASIBLE GIVEN UPSTREAM CONVECTION BUT
FAR FROM A CERTAINTY AT THIS POINT. MEANWHILE...WARMING TEMPERATURES
ALOFT WILL RESULT IN ELEVATED INSTABILITY WITH THE POTENTIAL FOR A
FEW THUNDERSTORMS.
OTHERWISE...TEMPERATURES WILL BE ON THE WARM SIDE TONIGHT...AS THE
INCREASING SSW FLOW LIMITS RADIATIONAL COOLING LATER IN THE NIGHT
AND EVENTUALLY DOWNSLOPE FROM THE LAKE ERIE SHORELINE AND NIAGARA FRONTIER
TO ROCHESTER.
THE WARM FRONT WILL LIFT NORTH OF THE REGION ON SUNDAY...WHICH
SHOULD END ANY LINGERING SHOWERS EAST OF LAKE ONTARIO BY SUNDAY
AFTERNOON. BEHIND THE FRONT SHOULD BE A FAIRLY DRY SW FLOW OF WARM
AIR. THIS FLOW SHOULD BOTH DOWNSLOPE AND WARM AIR IN NEARLY ALL
AREAS SOUTH OF LAKE ONTARIO WHICH SUPPORTS THE WARMER TEMPERATURE GUIDANCE.
OUTSIDE OF A FEW SPOTS ON THE NIAGARA FRONTIER AND EASTERN LAKE
ONTARIO SHORES...TEMPERATURES SHOULD CLIMB WELL INTO THE 70S...WITH
THE LOWER GENESEE VALLEY AND FINGER LAKES REGIONS LIKELY TO PUSH 80
IN A FEW SPOTS.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
WITH A WARM FRONT MOVING NORTHWARD ACROSS SOUTHERN ONTARIO...THE
VERY WARM AIRMASS WILL REMAIN IN PLACE THROUGH SUNDAY NIGHT.
DEWPOINTS WILL BE WELL INTO THE 50S AND LOWS ONLY IN THE UPPER
50S...IT WILL FEEL VERY MUCH LIKE A SUMMER NIGHT. MONDAY WILL START
ON A WARM NOTE AND TEMPS WILL RISE ACCORDINGLY TO HIGHS IN THE MID
70S TO THE LOWER 80S. AS THE COLD FRONT APPROACHES IN THE LATE
AFTERNOON...A LACK OF DEEP MOISTURE WILL BE A RESTRICTING FACTOR ON
THE DEVELOPMENT OF ANY CONVECTION UNTIL THE ARRIVAL OF DEEP MOISTURE
ADVECTION ALONG AND JUST AHEAD OF THE FRONTAL BOUNDARY. HOWEVER AS
WE MOVE INTO MONDAY EVENING PWATS ACROSS WESTERN NY SHOULD SURGE
ABOVE AN INCH LEADING TO THE DEVELOPMENT OF THUNDERSTORMS AHEAD OF
THE FRONT AS IT MOVES INTO WESTERN NY. WITH DECENT DYNAMICS AND WIND
FIELDS ALOFT...SOME OF THESE STORMS MAY FEATURE STRONG WINDS MONDAY
EVENING.
THE FRONT WILL SLOWLY MAKE ITS WAY ACROSS WESTERN AND NORTH CENTRAL
NEW YORK MONDAY NIGHT AND TUESDAY. THE COMBINATION OF FAVORABLE
UPPER LEVEL DYNAMICS AND DEEP MOISTURE ADVECTION ALONG WITH THE
ADDED ENHANCEMENT OF A SERIES OF SURFACE WAVES RIPPLING NORTHWARD
ALONG THE RELATIVELY SLOW-MOVING FRONTAL BOUNDARY WILL RESULT IN A
WIDESPREAD SOAKING RAINFALL ACROSS THE REGION WITH A SOLID ONE-
HALF TO ONE INCH OF RAINFALL POSSIBLE. THE COMBINATION OF THIS
RAINFALL AND THE CONSIDERABLE WARMING/THAWING ON MONDAY WILL
GENERATE THE FLOODING RISK ACROSS THE NORTH COUNTRY HIGHLIGHTED IN
THE HYDROLOGICAL PORTION OF THE DISCUSSION BELOW...BUT THAT`S NOT
ALL. MODEL GUIDANCE IS IN GOOD AGREEMENT THAT THE FRONTAL BOUNDARY
WILL TAKE ON ANAFRONTAL CHARACTERISTICS AS WARM AIR AHEAD OF THE
FRONT RIDES UP THE FRONTAL BOUNDARY PROPER...AND WITH SUCH COLD AIR
MOVING INTO THE REGION BEHIND THE FRONT THIS MAY LEAD TO A PERIOD OF
SNOWFALL AS THE BACK EDGE OF THE FRONT CROSSES THE AREA FROM EARLY
TUESDAY MORNING ONWARDS. A COATING TO ISOLATED AREAS WITH A COUPLE
OF INCHES OF SNOW ARE NOT OUT OF THE QUESTION AS ARCTIC AIR SETTLES
ACROSS THE REGION AND TEMPERATURES PLUMMET THROUGH THE DAY DOWN TO
THE 30S ON TUESDAY. READINGS WILL TUMBLE EVEN LOWER...INTO THE LOWER
20S WITH UPPER TEENS OVER HIGHER ELEVATIONS OF THE SOUTHERN TIER AND
THE NORTH COUNTRY AS HIGH PRESSURE SETTLES ACROSS THE REGION TUESDAY
NIGHT.
A COMPACT BUBBLE OF COLD HIGH PRESSURE WILL HOLD TEMPS DOWN TO THE
UPPER 30S TO LOW 40S ON WEDNESDAY...EVEN WITH A ADVANTAGE OF MID
APRIL SUNSHINE. PARTIAL CLOUDINESS WEDNESDAY NIGHT WILL NOT PROVIDE
ENOUGH OF A BLANKET TO KEEP OVERNIGHT LOW TEMPS FROM FALLING TO THE
MID TO UPPER 20S...EVEN TO THE UPPER TEENS ACROSS THE TUG HILL
PLATEAU.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AFTER AN UNSETTLED WEEKEND AND START TO THE WEEK...MUCH QUIETER
WEATHER WILL PREVAIL FOR THE LATTER HALF OF THE COMING WEEK AS A
BROAD DOME OF HIGH PRESSURE SHIFTS ACROSS THE GREAT LAKES.
THE CENTER OF THE HIGH PRESSURE CELL WILL BE OVER NORTHERN NEW
ENGLAND WITH A RIDGE AXIS SOUTHWESTWARD ACROSS THE ATLANTIC SEABOARD
AND APPALACHIANS. THIS WILL ESTABLISH A SOUTHERLY BOUNDARY LAYER
FLOW WITH A WARM ADVECTIVE PATTERN IN PLACE THROUGH THE END OF THE
WEEK. THE SLIGHTLY RIDGE UPPER PATTERN WILL PROTECT THE REGION FROM
NORTHWEST AND SOUTHEAST OF THE AREA THURSDAY AND FRIDAY...THEN AN
UPPER WAVE TRANSVERSING THE MID CONTINENT WILL DEVELOP LOW PRESSURE
OVER THE PLAINS AND BRING AN OCCLUDED LOW AND WEAK COLD FRONT ACROSS
THE REGION ON SATURDAY. 12Z GFS IS SUBSTANTIALLY STRONGER THAN 12Z
ECMWF PRECIP FIELD...BUT WILL SPLIT THE DIFFERENCE FOR NOW AND SEE
HOW THINGS TRANSPIRE WITH TIME.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL PREVAIL FOR THE BULK OF THE AREA THROUGH SUNDAY
AFTERNOON. A WARM FRONT WILL LIFT FROM SW-NE TONIGHT...WITH
INCREASING WINDS ALOFT RESULTING IN LLWS. THIS MAY BRING SHOWERS TO
SOME AREAS...WITH THE STEADIEST SHOWERS AT ART LATE TONIGHT WITH THE
FRONT. THERE MAY EVEN BE SOME THUNDERSTORMS DUE TO INSTABILITY
ALOFT. SHOWERS AND THUNDERSTORMS MAY BRIEFLY LOWER VSBY/CIGS TO MVFR
OR LOWER...BUT OUTSIDE OF SHOWERS EXPECT WIDESPREAD VFR CONDITIONS.
OUTLOOK...
SUNDAY NIGHT...MAINLY VFR.
MONDAY...DETERIORATION TO MVFR LATE WITH RAIN SHOWERS DEVELOPING
ALONG WITH A CHANCE OF THUNDERSTORMS.
TUESDAY AND TUESDAY NIGHT...MVFR/IFR WITH RAIN AND SNOW SHOWERS
DIMINISHING FROM WEST TO EAST.
WEDNESDAY AND THURSDAY...VFR.
&&
.MARINE...
HIGH PRESSURE WILL DRIFT INTO NEW ENGLAND WHILE A WARM FRONT LIFTS
ACROSS THE REGION TONIGHT. THIS WILL BRING AN INCREASING SSW FLOW
WHICH WILL LIKELY STAY BELOW SMALL CRAFT CRITERIA. WINDS WILL
INCREASE ON MONDAY AHEAD OF A STRONG COLD FRONT. SMALL CRAFT
ADVISORIES MAY BE NEEDED.
&&
.HYDROLOGY...
THERE CONTINUES TO BE HYDROLOGIC CONCERNS FOR PORTIONS OF THE
EASTERN LAKE ONTARIO REGION. SOME OF THE HIGHEST ELEVATIONS STILL
HAVE A SNOW PACK OF OVER A FOOT WITH WATER EQUIVALENTS OF 5 TO 8
INCHES...WITH SOME SNOW ALSO IN WOODED AREAS ELSEWHERE.
TEMPERATURES HAVE BEEN ABOVE NORMAL...AND ARE FORECAST TO BE EVEN
WARMER THROUGH MONDAY WHICH WILL LIKELY MELT MOST IF NOT ALL THE
SNOW PACK IN PLACE. INITIALLY...THIS WILL POSE THE RISK FOR RISES
IN CREEKS WHICH ARE FED BY SNOWMELT FROM THE TUG HILL.
BIGGER HYDROLOGIC CONCERNS DEVELOP DURING THE EARLY TO MID PART OF
NEXT WEEK AS A FRONTAL SYSTEM WORKS ACROSS THE REGION. A DEEP
MOISTURE PLUME RUNNING OUT AHEAD OF THE FRONTAL BOUNDARY COULD
PRODUCE AROUND AN INCH OF RAIN. THIS RAINFALL COMBINED WITH
THE SNOW MELT COULD PUSH THE BLACK RIVER TO FLOOD STAGE. MMEFS
ENSEMBLES SHOW THIS POTENTIAL...WITH MOST MEMBERS SUGGESTING A
CREST NEAR OR JUST ABOVE FLOOD STAGE. A FLOOD WATCH REMAINS IN
EFFECT FOR THE EASTERN LAKE ONTARIO REGION.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...FLOOD WATCH FROM SUNDAY MORNING THROUGH LATE WEDNESDAY NIGHT
FOR NYZ006>008.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...WCH
LONG TERM...WCH
AVIATION...APFFEL
MARINE...APFFEL/WCH
HYDROLOGY...HITCHCOCK/APFFEL
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1057 AM EDT SAT APR 12 2014
.SYNOPSIS...
A WEAK AREA OF HIGH PRESSURE WILL PROVIDE SUNSHINE AND WARMER
TEMPERATURES TODAY. A WARM FRONT WILL THEN LIFT NORTHEAST ACROSS THE
REGION TONIGHT WITH A CHANCE OF A FEW SHOWERS. THIS FRONT WILL USHER
IN THE WARMEST AIR OF THE SPRING SO FAR SUNDAY AND MONDAY WITH
TEMPERATURES SOARING WELL INTO THE 70S. A STRONG COLD FRONT WILL
SLOWLY CROSS THE REGION LATE MONDAY THROUGH TUESDAY WITH PERIODS OF
RAIN AND POSSIBLY A FEW THUNDERSTORMS INITIALLY. THE RAIN MAY END AS
A PERIOD OF WET SNOW ON TUESDAY AS MUCH COLDER AIR FILTERS INTO THE
REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE WILL BRING MOSTLY SUNNY SKIES AND PLEASANTLY WARM
TEMPERATURES TO MOST OF THE REGION. THE 12Z BUFFALO SOUNDING
SHOWS BOUNDARY LAYER TEMPERATURES ABOUT 8 DEGREES WARMER THAN
YESTERDAY...AND AS A GENERAL RULE OF THUMB THIS SHOULD GENERALLY
BRING HIGHS IN THE UPPER 60S INLAND. LIKE YESTERDAY LAKE BREEZES
WILL DEVELOP AND BRING SIGNIFICANTLY COOLER TEMPERATURES TO THE
IMMEDIATE LAKE SHORES. LAKE BREEZES TEND TO BE BEST CAPTURED BY HIGH
RESOLUTION GUIDANCE...SUCH AS THE HRRR/WRF...WITH THIS GUIDANCE
SHOWING THE LAKE ONTARIO LAKE BREEZE SPREADING FAR INLAND BY LATE
AFTERNOON...WHICH MAY RESULT IN A DROP IN TEMPERATURES ALL THE WAY
TO THE NYS THRUWAY LATE IN THE DAY. OTHERWISE...EXPECT MOSTLY
SUNNY SKIES THROUGH A THIN LAYER OF MID-HIGH CLOUDS.
FOG IN THE SOUTHERN TIER HAS DISSIPATED BUT LIKE YESTERDAY THERE
IS A POTENTIAL THAT FOG WILL DEVELOP ON THE LAKES. THROUGH LATE
MORNING...THERE IS NOT MUCH FOG ON THE LAKES AND WITH LOWER DEW
POINTS TODAY THE POTENTIAL IS MUCH LESS THAN YESTERDAY. HOWEVER...THE
PAST COUPLE RUNS OF THE HRRR DO DEVELOP SOME FOG NEAR THE ERIE
LAKE BREEZES...SO THIS WILL BE MONITORED.
TONIGHT INCREASING SOUTHWEST FLOW ALOFT AHEAD OF A DIGGING TROUGH
OVER THE NORTHERN PLAINS WILL FORCE WARM ADVECTION TO INCREASE
ACROSS THE LOWER LAKES. A WARM FRONTAL SEGMENT WILL STRENGTHEN OVER
OUR REGION...WITH ISENTROPIC UPGLIDE ENHANCED BY A 50+ KNOT LOW
LEVEL JET. THIS WILL BRING AN INCREASE IN CLOUD COVER ALONG WITH A
CHANCE OF A FEW SHOWERS OVERNIGHT. THE LOWEST RAIN CHANCES WILL BE
NEAR THE PA STATE LINE...WITH THE GREATEST CHANCES OVER LAKE ONTARIO
AND ACROSS THE NORTH COUNTRY WHERE MOISTURE AND ISENTROPIC UPGLIDE
ARE MAXIMIZED. SOME MODEST ELEVATED INSTABILITY IS FORECAST TO
DEVELOP WITH MUCAPE OF AROUND 300-500J/KG...POSSIBLY SUPPORTING AN
ISOLATED WEAK THUNDERSTORM.
THE DEEPENING SOUTHERLY FLOW WILL KEEP TEMPERATURES WELL ABOVE
AVERAGE...WITH LOWS ONLY IN THE LOWER TO MID 50S IN MANY AREAS FROM
SOUTHERN OSWEGO COUNTY WESTWARD...WITH LOW TO MID 40S ACROSS THE
NORTH COUNTRY. THESE LOWS WILL LIKELY OCCUR AROUND MIDNIGHT...WITH
TEMPERATURES RISING LATE. SOME AREAS FROM THE LAKE ERIE SHORE AND
NIAGARA FRONTIER EAST TO ROCHESTER MAY REACH THE LOW TO MID 60S BY
8AM SUNDAY AIDED BY INCREASING SOUTHERLY DOWNSLOPE FLOW.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
THE MAIN STORY DURING THIS PERIOD WILL BE THE DEEP UPPER LEVEL
TROUGH DIGGING ACROSS THE CENTRAL UNITED STATES AND THE SHOT OF
ACCOMPANYING ARCTIC AIR. AS WE OPEN THE PERIOD SUNDAY MORNING AN
ELONGATED SURFACE TROUGH STRETCHING FROM TEXAS TO ONTARIO WILL BE
FOUND ON THE LEADING EDGE OF THIS SHARPENING BAROCLINIC GRADIENT. A
FEW LINGERING SHOWERS AND POSSIBLY A THUNDERSTORM OR TWO ASSOCIATED
WITH SATURDAY NIGHT/S WARM FRONTAL PASSAGE MAY STILL BE IN THE
PROCESS OF LIFTING OUT OF THE NORTH COUNTRY SUNDAY MORNING...BUT
OTHERWISE IT SHOULD BE A DRY AND UNSEASONABLY WARM DAY FOR THE BULK
OF WESTERN AND NORTH-CENTRAL NEW YORK AS THE AREA WILL BE FIRMLY
PLANTED IN THE WARM SECTOR OF THE LOW PRESSURE TO OUR WEST. WITH
850MB TEMPS SURGING TO +12C AND ABUNDANT SUNSHINE ALLOWING FOR A
WELL-MIXED BOUNDARY LAYER...MID 70S SHOULD BE EASILY ATTAINABLE FOR
MOST AREAS WITH THE EXCEPTION OF THE NORTHERN ERIE AND JEFFERSON
COUNTY SHORELINES WHERE THE CHILLY LAKE WATERS WILL MODERATE
TEMPERATURES CONSIDERABLY. ON THE OTHER HAND...WITH SOUTHWESTERLY
WINDS GUSTING UPWARDS OF 30KTS BY THE AFTERNOON THANKS TO THAT
WELL-MIXED BOUNDARY LAYER...DOWNSLOPING COULD PUSH READINGS INTO THE
UPPER 70S ACROSS THE GENESEE VALLEY AND NORTH OF THE FINGER LAKES.
THIS VERY WARM AIRMASS WILL REMAIN IN PLACE THROUGH SUNDAY NIGHT.
WITH DEWPOINTS CLIMBING WELL INTO THE 50S AND LOWS ONLY DROPPING
INTO THE UPPER 50S...IT WILL FEEL VERY MUCH LIKE SUMMER OUTSIDE.
THIS WARMTH WILL PERSIST INTO MONDAY WITH TEMPERATURES ONCE AGAIN
CLIMBING WELL INTO THE 70S BY EARLY AFTERNOON EVEN AS THE STRONG
COLD FRONT MARKING THE BOUNDARY BETWEEN THIS WARM MOIST AIRMASS AND
THE ARCTIC AIR OVER THE UPPER MIDWEST APPROACHES THE LOWER GREAT
LAKES. BY LATE AFTERNOON/EARLY EVENING THE FRONT WILL BE ON OUR
DOORSTEP. WHILE THE AREA WILL BE INCREASINGLY WARM AND UNSTABLE
THROUGH THE DAY...A LACK OF DEEP MOISTURE WILL BE A RESTRICTING
FACTOR ON THE DEVELOPMENT OF ANY CONVECTION UNTIL THE ARRIVAL OF
DEEP MOISTURE ADVECTION ALONG AND JUST AHEAD OF THE FRONTAL
BOUNDARY. HOWEVER AS WE MOVE INTO MONDAY EVENING PWATS ACROSS
WESTERN NY SHOULD SURGE ABOVE AN INCH LEADING TO THE DEVELOPMENT OF
THUNDERSTORMS AHEAD OF THE FRONT AS IT MOVES INTO WESTERN NY. WITH
DECENT DYNAMICS AND WIND FIELDS ALOFT...SOME OF THESE STORMS MAY
FEATURE STRONG WINDS MONDAY EVENING.
THE FRONT WILL SLOWLY MAKE ITS WAY ACROSS WESTERN AND NORTH CENTRAL
NEW YORK MONDAY NIGHT AND TUESDAY. THE COMBINATION OF FAVORABLE
UPPER LEVEL DYNAMICS AND DEEP MOISTURE ADVECTION ALONG WITH THE
ADDED ENHANCEMENT OF A SERIES OF SURFACE WAVES RIPPLING NORTHWARD
ALONG THE RELATIVELY SLOW-MOVING FRONTAL BOUNDARY WILL RESULT IN A
WIDESPREAD SOAKING RAINFALL ACROSS THE REGION WITH A SOLID ONE-
HALF TO ONE INCH OF RAINFALL POSSIBLE. THE COMBINATION OF THIS
RAINFALL AND THE CONSIDERABLE WARMING/THAWING BEFOREHAND ON SUNDAY
AND MONDAY WILL GENERATE THE FLOODING RISK ACROSS THE NORTH
COUNTRY HIGHLIGHTED IN THE HYDROLOGICAL PORTION OF THE DISCUSSION
BELOW...BUT THAT`S NOT ALL. MODEL GUIDANCE IS IN GOOD AGREEMENT
THAT THE FRONTAL BOUNDARY WILL TAKE ON ANAFRONTAL CHARACTERISTICS
AS WARM AIR AHEAD OF THE FRONT RIDES UP THE FRONTAL BOUNDARY
PROPER...AND WITH SUCH COLD AIR MOVING INTO THE REGION BEHIND THE
FRONT THIS MAY LEAD TO A PERIOD OF SNOWFALL AS THE BACK EDGE OF
THE FRONT CROSSES THE AREA FROM EARLY TUESDAY MORNING ONWARDS. A
COUPLE OF INCHES OF SNOW ARE NOT OUT OF THE QUESTION AS ARCTIC AIR
SETTLES ACROSS THE REGION AND TEMPERATURES PLUMMET INTO THE 30S ON
TUESDAY. READINGS WILL TUMBLE EVEN LOWER...INTO THE LOWER 20S WITH
UPPER TEENS OVER HIGHER ELEVATIONS OF THE SOUTHERN TIER AND THE
NORTH COUNTRY AS HIGH PRESSURE SETTLES ACROSS THE REGION TUESDAY
NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AFTER AN UNSETTLED WEEKEND AND START TO THE WEEK...MUCH QUIETER
WEATHER WILL PREVAIL FOR THE LATTER HALF OF THE COMING WEEK AS A
BROAD DOME OF HIGH PRESSURE SHIFTS ACROSS THE GREAT LAKES. ARCTIC
AIR WILL HAVE THE UPPER HAND ON WEDNESDAY IN THE WAKE OF TUESDAY`S
STRONG COLD FRONTAL PASSAGE AND HIGHS ON WEDNESDAY WILL ONLY TOP OUT
IN THE UPPER 30S ACROSS MOST AREAS.
BY WEDNESDAY NIGHT THE CENTER OF THE HIGH MOVES OUT INTO THE GULF OF
SAINT LAWRENCE AND AN UPPER LEVEL SHORTWAVE DIGGING OUT OF THE
PACIFIC NORTHWEST BEGINS TO CARVE OUT A TROUGH ACROSS THE ROCKIES
AND EVENTUALLY THE NATION`S MID-SECTION. WHILE THERE IS STILL
CONSIDERABLE SPREAD AMONG THE MODELS REGARDING THE AMPLITUDE OF THIS
TROUGH...EITHER WAY THE LOWER GREAT LAKES WILL END UP UNDER THE
INFLUENCE OF DOWNSTREAM RIDGING WITH MERIDIONAL FLOW THAT WILL
GRADUALLY ADVECT WARMER AIR ACROSS THE REGION. THIS WILL ALLOW FOR
TEMPERATURES TO REBOUND INTO THE 40S THURSDAY AND THE 50S FRIDAY.
THIS RIDGING WILL ALSO KEEP CONDITIONS DRY AT LEAST THROUGH THURSDAY
NIGHT AND POSSIBLY THROUGH FRIDAY...HOWEVER THAT WILL DEPEND ON THE
SPEED WITH WHICH THE AFOREMENTIONED TROUGHING OVER THE CENTRAL U.S.
MOVES EASTWARD...AN ISSUE STILL IN CONTENTION AMONG THE MODELS AS
PREVIOUSLY MENTIONED.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL FOR THE BULK OF THE AREA FOR THE 15Z
TAF CYCLE. STRONGER WARM ADVECTION WILL DEVELOP TONIGHT WITH
THICKENING AND LOWERING MID LEVEL CLOUDS AND POSSIBLY A FEW WIDELY
SCATTERED SHOWERS. LOW LEVEL WIND SHEAR WILL LIKELY DEVELOP
OVERNIGHT AS A LOW LEVEL JET CROSSES THE LOWER LAKES.
OUTLOOK...
SUNDAY...MAINLY VFR WITH A CHANCE OF SHOWERS IN THE MORNING.
MONDAY...DETERIORATION TO MVFR LATE WITH RAIN SHOWERS DEVELOPING
ALONG WITH A CHANCE OF THUNDERSTORMS.
TUESDAY...MVFR/IFR WITH RAIN AND SNOW SHOWERS DIMINISHING FROM WEST
TO EAST.
WEDNESDAY...VFR EXPECTED WITH A CHANCE FOR LOCAL IFR FOG.
&&
.MARINE...
HIGH PRESSURE WILL DRIFT SLOWLY AWAY FROM THE REGION TODAY WITH
RELATIVELY LIGHT WINDS CONTINUING. THE WEAK SYNOPTIC SCALE GRADIENT
AND STRONG DIFFERENTIAL HEATING WILL SUPPORT THE DEVELOPMENT OF LAKE
BREEZE CIRCULATIONS TODAY...WITH WINDS BECOMING ONSHORE ALONG ALL
THE LAKESHORES. A WARM FRONT WILL LIFT NORTHEAST ACROSS THE LOWER
LAKES TONIGHT WITH EASTERLY WINDS BECOMING SOUTHERLY AND INCREASING
LATE.
&&
.HYDROLOGY...
HYDROLOGIC CONCERNS GROWING FOR AREAS OF THE EASTERN LAKE ONTARIO
REGION WHERE A SNOWPACK REMAINS IN PLACE. SOME OF THE HIGHEST
ELEVATIONS STILL HAVE A SNOW PACK OF OVER A FOOT WITH WATER
EQUIVALENTS OF 5 TO 8 INCHES. WATER LEVELS HAVE STEADILY RISEN
WITH EVEN SOME OF THE LARGER MAIN STEM RIVERS IN OR APPROACHING
ACTION STAGE. TEMPERATURES ARE EXPECTED TO WELL WARM ABOVE NORMAL
LEVELS FOR THE WEEKEND WHICH WILL CONTINUE THE SNOW MELTING
PROCESS AND CAUSE WATER LEVELS TO CONTINUE TO SLOWLY RISE. ANY
FLOODING ISSUES THIS WEEKEND SHOULD BE ONLY MINOR AND CONFINED TO
THE SMALLER CREEKS AND STREAMS. THIS WOULD BE MORE LIKELY SUNDAY
WHEN DEWPOINTS RISE AND INCREASE THE RATE OF SNOWMELT.
BIGGER HYDROLOGIC CONCERNS DEVELOP DURING THE EARLY TO MID PART OF
NEXT WEEK AS A FRONTAL SYSTEM WORKS ACROSS THE REGION. A DEEP
MOISTURE PLUME RUNNING OUT AHEAD OF THE FRONTAL BOUNDARY COULD
PRODUCE LOCALLY HEAVY RAINFALL IN EXCESS OF AN INCH. THIS RAINFALL
COMBINED WITH ADDITIONAL SNOW MELT WILL BRING A MORE SIGNIFICANT
FLOODING POTENTIAL NOT ONLY ON THE SMALLER CREEKS AND STREAMS...
BUT THE MAIN STEM RIVERS AS WELL. THE POTENTIAL EXISTS FOR THE
BLACK RIVER TO REACH MINOR FLOOD LEVELS BY WEDNESDAY.
A FLOOD WATCH HAS BEEN ISSUED TO COVER THIS POTENTIAL...PRIMARILY
FOR STREAMS AND RIVERS WHICH HAVE SOURCE REGIONS ON THE TUG HILL
PLATEAU AND THE WESTERN ADIRONDACKS.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...FLOOD WATCH FROM SUNDAY MORNING THROUGH LATE WEDNESDAY NIGHT
FOR NYZ006>008.
MARINE...NONE.
&&
$$
SYNOPSIS...HITCHCOCK
NEAR TERM...APFFEL/HITCHCOCK
SHORT TERM...WOOD
LONG TERM...WOOD
AVIATION...APFFEL/HITCHCOCK
MARINE...HITCHCOCK
HYDROLOGY...TMA/HITCHCOCK
AREA FORECAST DISCUSSION
NWS BUFFALO NY
735 AM EDT SAT APR 12 2014
.SYNOPSIS...
A WEAK AREA OF HIGH PRESSURE WILL PROVIDE SUNSHINE AND WARMER
TEMPERATURES TODAY. A WARM FRONT WILL THEN LIFT NORTHEAST ACROSS THE
REGION TONIGHT WITH A CHANCE OF A FEW SHOWERS. THIS FRONT WILL USHER
IN THE WARMEST AIR OF THE SPRING SO FAR SUNDAY AND MONDAY WITH
TEMPERATURES SOARING WELL INTO THE 70S. A STRONG COLD FRONT WILL
SLOWLY CROSS THE REGION LATE MONDAY THROUGH TUESDAY WITH PERIODS OF
RAIN AND POSSIBLY A FEW THUNDERSTORMS INITIALLY. THE RAIN MAY END AS
A PERIOD OF WET SNOW ON TUESDAY AS MUCH COLDER AIR FILTERS INTO THE
REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
A BATCH OF HIGH CIRRUS LEVEL CLOUDS IS OVERSPREADING WESTERN NY
EARLY THIS MORNING...AND WILL CONTINUE EAST INTO CENTRAL NY BY MID
MORNING. THIS SHOULD BEGIN TO THIN OUT BY MIDDAY.
11-3.9 MICRON IR SATELLITE IMAGERY SHOWS AN AREA OF WIDESPREAD FOG
OVER PENNSYLVANIA AND THE WESTERN SOUTHERN TIER EARLY THIS MORNING.
THIS HAS ENVELOPED MUCH OF CHAU/CATT/ALLEG COUNTIES. A DENSE FOG
ADVISORY REMAINS FOR THIS AREA THROUGH MID MORNING. THIS IS
RADIATIONAL FOG AND DIURNAL IN NATURE...SO IT WILL BURN OFF WITH THE
ONSET OF DAYTIME MIXING.
THE OTHER POTENTIAL FOG AREA WILL BE OVER AND JUST EAST AND
NORTHEAST OF LAKE ERIE. AS SOUTHWEST FLOW DEVELOPS THIS MORNING...
MODESTLY HIGHER DEWPOINTS IN THE UPPER 30S WILL SPREAD ACROSS THE
LAKE ERIE ICE COVER AND MAY PRODUCE A PLUME OF FOG OVER THE LAKE. IF
THIS DEVELOPS...THE WEAK SOUTHWEST FLOW WOULD BRING IT INTO THE ERIE
COUNTY SHORELINE AND EVENTUALLY THE CHAUTAUQUA COUNTY SHORELINE
LATER TODAY. THE AIRMASS IS DRIER THAN YESTERDAY MORNING...SO
CONFIDENCE IS NOT THAT GREAT. THE PAST FEW RUNS OF THE HRRR ARE
PICKING UP ON THIS POSSIBILITY HOWEVER...DEVELOPING AN AREA OF LOW
CIGS AND VSBY OVER AND JUST DOWNWIND OF LAKE ERIE. WITH THIS IN
MIND...HAVE ADDED AREAS OF FOG ALONG THE LAKE ERIE SHORE FOR
TODAY...BUT AGAIN CONFIDENCE IS NOT ALL THAT HIGH.
OTHER THAN THE FOG...SURFACE HIGH PRESSURE WILL DRIFT INTO THE MID
ATLANTIC TODAY BUT STILL HAVE ENOUGH CONTROL ACROSS OUR REGION TO
PROVIDE A GOOD AMOUNT OF SUNSHINE FOR MOST OF THE DAY. A BATCH OF
HIGH CIRRUS CLOUDS WILL ENTER WESTERN NY EARLY THIS MORNING...BUT
THEN THIN AS THEY MOVE ACROSS THE REST OF THE AREA. THICKER MID
LEVEL CLOUD WILL ARRIVE AT THE END OF THE DAY...ESPECIALLY FROM THE
NIAGARA FRONTIER ACROSS LAKE ONTARIO TO THE NORTH COUNTRY AS MID
LEVEL WARM ADVECTION RAPIDLY INCREASES.
850MB TEMPS RISE TO AROUND +7C ACROSS THE WEST AND +4C ACROSS THE
NORTH COUNTRY BY LATE AFTERNOON. THIS SHOULD SUPPORT HIGHS IN THE
MID TO UPPER 60S ACROSS MUCH OF THE AREA...WITH HIGHS OF 55 TO 60
ACROSS THE NORTH COUNTRY. LAKE BREEZES WILL DEVELOP TODAY AND KEEP
ALL THE LAKESHORE AREAS COOLER. THE LAKE ONTARIO LAKE BREEZE IS
FORECAST TO SPREAD FAR INLAND BY LATE AFTERNOON...WHICH MAY RESULT
IN A DROP IN TEMPERATURES ALL THE WAY SOUTH TO THE NYS THRUWAY LATE
IN THE DAY.
TONIGHT INCREASING SOUTHWEST FLOW ALOFT AHEAD OF A DIGGING TROUGH
OVER THE NORTHERN PLAINS WILL FORCE WARM ADVECTION TO INCREASE
ACROSS THE LOWER LAKES. A WARM FRONTAL SEGMENT WILL STRENGTHEN OVER
OUR REGION...WITH ISENTROPIC UPGLIDE ENHANCED BY A 50+ KNOT LOW
LEVEL JET. THIS WILL BRING AN INCREASE IN CLOUD COVER ALONG WITH A
CHANCE OF A FEW SHOWERS OVERNIGHT. THE LOWEST RAIN CHANCES WILL BE
NEAR THE PA STATE LINE...WITH THE GREATEST CHANCES OVER LAKE ONTARIO
AND ACROSS THE NORTH COUNTRY WHERE MOISTURE AND ISENTROPIC UPGLIDE
ARE MAXIMIZED. SOME MODEST ELEVATED INSTABILITY IS FORECAST TO
DEVELOP WITH MUCAPE OF AROUND 300-500J/KG...POSSIBLY SUPPORTING AN
ISOLATED WEAK THUNDERSTORM.
THE DEEPENING SOUTHERLY FLOW WILL KEEP TEMPERATURES WELL ABOVE
AVERAGE...WITH LOWS ONLY IN THE LOWER TO MID 50S IN MANY AREAS FROM
SOUTHERN OSWEGO COUNTY WESTWARD...WITH LOW TO MID 40S ACROSS THE
NORTH COUNTRY. THESE LOWS WILL LIKELY OCCUR AROUND MIDNIGHT...WITH
TEMPERATURES RISING LATE. SOME AREAS FROM THE LAKE ERIE SHORE AND
NIAGARA FRONTIER EAST TO ROCHESTER MAY REACH THE LOW TO MID 60S BY
8AM SUNDAY AIDED BY INCREASING SOUTHERLY DOWNSLOPE FLOW.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
THE MAIN STORY DURING THIS PERIOD WILL BE THE DEEP UPPER LEVEL
TROUGH DIGGING ACROSS THE CENTRAL UNITED STATES AND THE SHOT OF
ACCOMPANYING ARCTIC AIR. AS WE OPEN THE PERIOD SUNDAY MORNING AN
ELONGATED SURFACE TROUGH STRETCHING FROM TEXAS TO ONTARIO WILL BE
FOUND ON THE LEADING EDGE OF THIS SHARPENING BAROCLINIC GRADIENT. A
FEW LINGERING SHOWERS AND POSSIBLY A THUNDERSTORM OR TWO ASSOCIATED
WITH SATURDAY NIGHT/S WARM FRONTAL PASSAGE MAY STILL BE IN THE
PROCESS OF LIFTING OUT OF THE NORTH COUNTRY SUNDAY MORNING...BUT
OTHERWISE IT SHOULD BE A DRY AND UNSEASONABLY WARM DAY FOR THE BULK
OF WESTERN AND NORTH-CENTRAL NEW YORK AS THE AREA WILL BE FIRMLY
PLANTED IN THE WARM SECTOR OF THE LOW PRESSURE TO OUR WEST. WITH
850MB TEMPS SURGING TO +12C AND ABUNDANT SUNSHINE ALLOWING FOR A
WELL-MIXED BOUNDARY LAYER...MID 70S SHOULD BE EASILY ATTAINABLE FOR
MOST AREAS WITH THE EXCEPTION OF THE NORTHERN ERIE AND JEFFERSON
COUNTY SHORELINES WHERE THE CHILLY LAKE WATERS WILL MODERATE
TEMPERATURES CONSIDERABLY. ON THE OTHER HAND...WITH SOUTHWESTERLY
WINDS GUSTING UPWARDS OF 30KTS BY THE AFTERNOON THANKS TO THAT
WELL-MIXED BOUNDARY LAYER...DOWNSLOPING COULD PUSH READINGS INTO THE
UPPER 70S ACROSS THE GENESEE VALLEY AND NORTH OF THE FINGER LAKES.
THIS VERY WARM AIRMASS WILL REMAIN IN PLACE THROUGH SUNDAY NIGHT.
WITH DEWPOINTS CLIMBING WELL INTO THE 50S AND LOWS ONLY DROPPING
INTO THE UPPER 50S...IT WILL FEEL VERY MUCH LIKE SUMMER OUTSIDE.
THIS WARMTH WILL PERSIST INTO MONDAY WITH TEMPERATURES ONCE AGAIN
CLIMBING WELL INTO THE 70S BY EARLY AFTERNOON EVEN AS THE STRONG
COLD FRONT MARKING THE BOUNDARY BETWEEN THIS WARM MOIST AIRMASS AND
THE ARCTIC AIR OVER THE UPPER MIDWEST APPROACHES THE LOWER GREAT
LAKES. BY LATE AFTERNOON/EARLY EVENING THE FRONT WILL BE ON OUR
DOORSTEP. WHILE THE AREA WILL BE INCREASINGLY WARM AND UNSTABLE
THROUGH THE DAY...A LACK OF DEEP MOISTURE WILL BE A RESTRICTING
FACTOR ON THE DEVELOPMENT OF ANY CONVECTION UNTIL THE ARRIVAL OF
DEEP MOISTURE ADVECTION ALONG AND JUST AHEAD OF THE FRONTAL
BOUNDARY. HOWEVER AS WE MOVE INTO MONDAY EVENING PWATS ACROSS
WESTERN NY SHOULD SURGE ABOVE AN INCH LEADING TO THE DEVELOPMENT OF
THUNDERSTORMS AHEAD OF THE FRONT AS IT MOVES INTO WESTERN NY. WITH
DECENT DYNAMICS AND WIND FIELDS ALOFT...SOME OF THESE STORMS MAY
FEATURE STRONG WINDS MONDAY EVENING.
THE FRONT WILL SLOWLY MAKE ITS WAY ACROSS WESTERN AND NORTH CENTRAL
NEW YORK MONDAY NIGHT AND TUESDAY. THE COMBINATION OF FAVORABLE
UPPER LEVEL DYNAMICS AND DEEP MOISTURE ADVECTION ALONG WITH THE
ADDED ENHANCEMENT OF A SERIES OF SURFACE WAVES RIPPLING NORTHWARD
ALONG THE RELATIVELY SLOW-MOVING FRONTAL BOUNDARY WILL RESULT IN A
WIDESPREAD SOAKING RAINFALL ACROSS THE REGION WITH A SOLID ONE-
HALF TO ONE INCH OF RAINFALL POSSIBLE. THE COMBINATION OF THIS
RAINFALL AND THE CONSIDERABLE WARMING/THAWING BEFOREHAND ON SUNDAY
AND MONDAY WILL GENERATE THE FLOODING RISK ACROSS THE NORTH
COUNTRY HIGHLIGHTED IN THE HYDROLOGICAL PORTION OF THE DISCUSSION
BELOW...BUT THAT`S NOT ALL. MODEL GUIDANCE IS IN GOOD AGREEMENT
THAT THE FRONTAL BOUNDARY WILL TAKE ON ANAFRONTAL CHARACTERISTICS
AS WARM AIR AHEAD OF THE FRONT RIDES UP THE FRONTAL BOUNDARY
PROPER...AND WITH SUCH COLD AIR MOVING INTO THE REGION BEHIND THE
FRONT THIS MAY LEAD TO A PERIOD OF SNOWFALL AS THE BACK EDGE OF
THE FRONT CROSSES THE AREA FROM EARLY TUESDAY MORNING ONWARDS. A
COUPLE OF INCHES OF SNOW ARE NOT OUT OF THE QUESTION AS ARCTIC AIR
SETTLES ACROSS THE REGION AND TEMPERATURES PLUMMET INTO THE 30S ON
TUESDAY. READINGS WILL TUMBLE EVEN LOWER...INTO THE LOWER 20S WITH
UPPER TEENS OVER HIGHER ELEVATIONS OF THE SOUTHERN TIER AND THE
NORTH COUNTRY AS HIGH PRESSURE SETTLES ACROSS THE REGION TUESDAY
NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AFTER AN UNSETTLED WEEKEND AND START TO THE WEEK...MUCH QUIETER
WEATHER WILL PREVAIL FOR THE LATTER HALF OF THE COMING WEEK AS A
BROAD DOME OF HIGH PRESSURE SHIFTS ACROSS THE GREAT LAKES. ARCTIC
AIR WILL HAVE THE UPPER HAND ON WEDNESDAY IN THE WAKE OF TUESDAY`S
STRONG COLD FRONTAL PASSAGE AND HIGHS ON WEDNESDAY WILL ONLY TOP OUT
IN THE UPPER 30S ACROSS MOST AREAS.
BY WEDNESDAY NIGHT THE CENTER OF THE HIGH MOVES OUT INTO THE GULF OF
SAINT LAWRENCE AND AN UPPER LEVEL SHORTWAVE DIGGING OUT OF THE
PACIFIC NORTHWEST BEGINS TO CARVE OUT A TROUGH ACROSS THE ROCKIES
AND EVENTUALLY THE NATION`S MID-SECTION. WHILE THERE IS STILL
CONSIDERABLE SPREAD AMONG THE MODELS REGARDING THE AMPLITUDE OF THIS
TROUGH...EITHER WAY THE LOWER GREAT LAKES WILL END UP UNDER THE
INFLUENCE OF DOWNSTREAM RIDGING WITH MERIDIONAL FLOW THAT WILL
GRADUALLY ADVECT WARMER AIR ACROSS THE REGION. THIS WILL ALLOW FOR
TEMPERATURES TO REBOUND INTO THE 40S THURSDAY AND THE 50S FRIDAY.
THIS RIDGING WILL ALSO KEEP CONDITIONS DRY AT LEAST THROUGH THURSDAY
NIGHT AND POSSIBLY THROUGH FRIDAY...HOWEVER THAT WILL DEPEND ON THE
SPEED WITH WHICH THE AFOREMENTIONED TROUGHING OVER THE CENTRAL U.S.
MOVES EASTWARD...AN ISSUE STILL IN CONTENTION AMONG THE MODELS AS
PREVIOUSLY MENTIONED.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL FOR THE BULK OF THE AREA FOR THE 06Z TAF
CYCLE. A STRONG YET MOISTURE STARVED MID LEVEL DISTURBANCE WILL
CROSS THE REGION QUICKLY FROM WEST TO EAST THROUGH ABOUT 10Z AND MAY
PRODUCE A FEW SPRINKLES OVER AND NEAR LAKE ONTARIO OUT OF A MID
LEVEL CLOUD DECK. OTHERWISE FOR THE REST OF THE AREA JUST EXPECT
SOME PATCHY CIRRUS.
WIDESPREAD FOG HAS DEVELOPED ACROSS PENNSYLVANIA AND THE CENTRAL
SOUTHERN TIER OF NY. THIS WILL CONTINUE TO EXPAND SLOWLY NORTHWARD
INTO THE WESTERN SOUTHERN TIER WITH WIDESPREAD IFR...ESPECIALLY NEAR
THE PA STATE LINE. THIS FOG SHOULD MIX OUT BY MID MORNING SATURDAY.
FOG MAY ALSO DEVELOP OVER LAKE ERIE LATE TONIGHT...THEN SPREAD
TOWARDS KBUF AND KIAG FOR A FEW HOURS SATURDAY MORNING. THE AIRMASS
IS DRIER THAN IT WAS YESTERDAY MORNING...SO CONFIDENCE IS ONLY
MODERATE AT BEST THAT THIS WILL OCCUR. FOR NOW WILL JUST INCLUDE A
BRIEF TEMPO GROUP WITH IFR UNTIL IT BECOMES MORE APPARENT. IF THIS
DOES DEVELOP...IT MAY PERSIST THROUGH ABOUT MIDDAY BEFORE MIXING OUT.
OTHERWISE FOR THE REST OF SATURDAY EXPECT VFR WITH PASSING THIN
CIRRUS. STRONGER WARM ADVECTION WILL DEVELOP SATURDAY NIGHT WITH
THICKENING AND LOWERING MID LEVEL CLOUDS AND POSSIBLY A FEW WIDELY
SCATTERED SHOWERS. LOW LEVEL WIND SHEAR MAY DEVELOP OVERNIGHT AS A
LOW LEVEL JET CROSSES THE LOWER LAKES.
OUTLOOK...
SUNDAY...MAINLY VFR WITH A CHANCE OF SHOWERS IN THE MORNING.
MONDAY...DETERIORATION TO MVFR LATE WITH RAIN SHOWERS DEVELOPING
ALONG WITH A CHANCE OF THUNDERSTORMS.
TUESDAY...MVFR/IFR WITH RAIN AND SNOW SHOWERS DIMINISHING FROM WEST
TO EAST.
WEDNESDAY...VFR EXPECTED WITH A CHANCE FOR LOCAL IFR FOG.
&&
.MARINE...
HIGH PRESSURE WILL DRIFT SLOWLY AWAY FROM THE REGION TODAY WITH
RELATIVELY LIGHT WINDS CONTINUING. THE WEAK SYNOPTIC SCALE GRADIENT
AND STRONG DIFFERENTIAL HEATING WILL SUPPORT THE DEVELOPMENT OF LAKE
BREEZE CIRCULATIONS TODAY...WITH WINDS BECOMING ONSHORE ALONG ALL
THE LAKESHORES. A WARM FRONT WILL LIFT NORTHEAST ACROSS THE LOWER
LAKES TONIGHT WITH EASTERLY WINDS BECOMING SOUTHERLY AND INCREASING
LATE.
&&
.HYDROLOGY...
HYDROLOGIC CONCERNS GROWING FOR AREAS OF THE EASTERN LAKE ONTARIO
REGION WHERE A SNOWPACK REMAINS IN PLACE. SOME OF THE HIGHEST
ELEVATIONS STILL HAVE A SNOW PACK OF OVER A FOOT WITH WATER
EQUIVALENTS OF 5 TO 8 INCHES. WATER LEVELS HAVE STEADILY RISEN
WITH EVEN SOME OF THE LARGER MAIN STEM RIVERS IN OR APPROACHING
ACTION STAGE. TEMPERATURES ARE EXPECTED TO WELL WARM ABOVE NORMAL
LEVELS FOR THE WEEKEND WHICH WILL CONTINUE THE SNOW MELTING
PROCESS AND CAUSE WATER LEVELS TO CONTINUE TO SLOWLY RISE. ANY
FLOODING ISSUES THIS WEEKEND SHOULD BE ONLY MINOR AND CONFINED TO
THE SMALLER CREEKS AND STREAMS. THIS WOULD BE MORE LIKELY SUNDAY
WHEN DEWPOINTS RISE AND INCREASE THE RATE OF SNOWMELT.
BIGGER HYDROLOGIC CONCERNS DEVELOP DURING THE EARLY TO MID PART OF
NEXT WEEK AS A FRONTAL SYSTEM WORKS ACROSS THE REGION. A DEEP
MOISTURE PLUME RUNNING OUT AHEAD OF THE FRONTAL BOUNDARY COULD
PRODUCE LOCALLY HEAVY RAINFALL IN EXCESS OF AN INCH. THIS RAINFALL
COMBINED WITH ADDITIONAL SNOW MELT WILL BRING A MORE SIGNIFICANT
FLOODING POTENTIAL NOT ONLY ON THE SMALLER CREEKS AND STREAMS...
BUT THE MAIN STEM RIVERS AS WELL. THE POTENTIAL EXISTS FOR THE
BLACK RIVER TO REACH MINOR FLOOD LEVELS BY WEDNESDAY.
A FLOOD WATCH HAS BEEN ISSUED TO COVER THIS POTENTIAL...PRIMARILY
FOR STREAMS AND RIVERS WHICH HAVE SOURCE REGIONS ON THE TUG HILL
PLATEAU AND THE WESTERN ADIRONDACKS.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...FLOOD WATCH FROM SUNDAY MORNING THROUGH LATE WEDNESDAY NIGHT
FOR NYZ006>008.
DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR NYZ019>021.
MARINE...NONE.
&&
$$
SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...WOOD
LONG TERM...WOOD
AVIATION...HITCHCOCK
MARINE...HITCHCOCK
HYDROLOGY...TMA/HITCHCOCK
AREA FORECAST DISCUSSION
NWS BUFFALO NY
452 AM EDT SAT APR 12 2014
.SYNOPSIS...
A WEAK AREA OF HIGH PRESSURE WILL PROVIDE SUNSHINE AND WARMER
TEMPERATURES TODAY. A WARM FRONT WILL THEN LIFT NORTHEAST ACROSS THE
REGION TONIGHT WITH A CHANCE OF A FEW SHOWERS. THIS FRONT WILL USHER
IN THE WARMEST AIR OF THE SPRING SO FAR SUNDAY AND MONDAY WITH
TEMPERATURES SOARING WELL INTO THE 70S. A STRONG COLD FRONT WILL
SLOWLY CROSS THE REGION LATE MONDAY THROUGH TUESDAY WITH PERIODS OF
RAIN AND POSSIBLY A FEW THUNDERSTORMS INITIALLY. THE RAIN MAY END AS
A PERIOD OF WET SNOW ON TUESDAY AS MUCH COLDER AIR FILTERS INTO THE
REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
A STRONG YET MOISTURE STARVED SHORTWAVE WILL EXIT THE NORTH COUNTRY
AROUND DAYBREAK WITH A FEW PATCHES OF MID LEVEL CLOUD MOVING AWAY
FROM THE REGION. THIS FEATURE PRODUCED A FEW SHOWERS OVER WESTERN
LAKE ONTARIO EARLIER...BUT THESE HAVE SINCE DISSIPATED AS DRY AIR
CONTINUES TO WIN OUT.
11-3.9 MICRON IR SATELLITE IMAGERY SHOWS AN AREA OF WIDESPREAD FOG
SPREADING NORTH OUT OF PENNSYLVANIA AND INTO THE WESTERN SOUTHERN
TIER EARLY THIS MORNING. THIS MAY CONTINUE TO CREEP NORTHWARD FOR A
FEW MORE HOURS AND ENVELOPE MUCH OF CHAU/CATT/ALLEG COUNTIES. WITH
THIS IN MIND...WILL RUN A DENSE FOG ADVISORY FOR THIS AREA THROUGH
MID MORNING. THIS IS RADIATIONAL FOG AND DIURNAL IN NATURE...SO IT
WILL BURN OFF WITH THE ONSET OF DAYTIME MIXING.
THE OTHER POTENTIAL FOG AREA WILL BE OVER AND JUST EAST AND
NORTHEAST OF LAKE ERIE. AS SOUTHWEST FLOW DEVELOPS THIS MORNING...
MODESTLY HIGHER DEWPOINTS IN THE UPPER 30S WILL SPREAD ACROSS THE
LAKE ERIE ICE COVER AND MAY PRODUCE A PLUME OF FOG OVER THE LAKE. IF
THIS DEVELOPS...THE WEAK SOUTHWEST FLOW WOULD BRING IT INTO THE ERIE
COUNTY SHORELINE AND EVENTUALLY THE CHAUTAUQUA COUNTY SHORELINE
LATER TODAY. THE AIRMASS IS DRIER THAN YESTERDAY MORNING...SO
CONFIDENCE IS NOT THAT GREAT. THE PAST FEW RUNS OF THE HRRR ARE
PICKING UP ON THIS POSSIBILITY HOWEVER...DEVELOPING AN AREA OF LOW
CIGS AND VSBY OVER AND JUST DOWNWIND OF LAKE ERIE. WITH THIS IN
MIND...HAVE ADDED AREAS OF FOG ALONG THE LAKE ERIE SHORE FOR
TODAY...BUT AGAIN CONFIDENCE IS NOT ALL THAT HIGH.
OTHER THAN THE FOG...SURFACE HIGH PRESSURE WILL DRIFT INTO THE MID
ATLANTIC TODAY BUT STILL HAVE ENOUGH CONTROL ACROSS OUR REGION TO
PROVIDE A GOOD AMOUNT OF SUNSHINE FOR MOST OF THE DAY. A BATCH OF
HIGH CIRRUS CLOUDS WILL ENTER WESTERN NY EARLY THIS MORNING...BUT
THEN THIN AS THEY MOVE ACROSS THE REST OF THE AREA. THICKER MID
LEVEL CLOUD WILL ARRIVE AT THE END OF THE DAY...ESPECIALLY FROM THE
NIAGARA FRONTIER ACROSS LAKE ONTARIO TO THE NORTH COUNTRY AS MID
LEVEL WARM ADVECTION RAPIDLY INCREASES.
850MB TEMPS RISE TO AROUND +7C ACROSS THE WEST AND +4C ACROSS THE
NORTH COUNTRY BY LATE AFTERNOON. THIS SHOULD SUPPORT HIGHS IN THE
MID TO UPPER 60S ACROSS MUCH OF THE AREA...WITH HIGHS OF 55 TO 60
ACROSS THE NORTH COUNTRY. LAKE BREEZES WILL DEVELOP TODAY AND KEEP
ALL THE LAKESHORE AREAS COOLER. THE LAKE ONTARIO LAKE BREEZE IS
FORECAST TO SPREAD FAR INLAND BY LATE AFTERNOON...WHICH MAY RESULT
IN A DROP IN TEMPERATURES ALL THE WAY SOUTH TO THE NYS THRUWAY LATE
IN THE DAY.
TONIGHT INCREASING SOUTHWEST FLOW ALOFT AHEAD OF A DIGGING TROUGH
OVER THE NORTHERN PLAINS WILL FORCE WARM ADVECTION TO INCREASE
ACROSS THE LOWER LAKES. A WARM FRONTAL SEGMENT WILL STRENGTHEN OVER
OUR REGION...WITH ISENTROPIC UPGLIDE ENHANCED BY A 50+ KNOT LOW
LEVEL JET. THIS WILL BRING AN INCREASE IN CLOUD COVER ALONG WITH A
CHANCE OF A FEW SHOWERS OVERNIGHT. THE LOWEST RAIN CHANCES WILL BE
NEAR THE PA STATE LINE...WITH THE GREATEST CHANCES OVER LAKE ONTARIO
AND ACROSS THE NORTH COUNTRY WHERE MOISTURE AND ISENTROPIC UPGLIDE
ARE MAXIMIZED. SOME MODEST ELEVATED INSTABILITY IS FORECAST TO
DEVELOP WITH MUCAPE OF AROUND 300-500J/KG...POSSIBLY SUPPORTING AN
ISOLATED WEAK THUNDERSTORM.
THE DEEPENING SOUTHERLY FLOW WILL KEEP TEMPERATURES WELL ABOVE
AVERAGE...WITH LOWS ONLY IN THE LOWER TO MID 50S IN MANY AREAS FROM
SOUTHERN OSWEGO COUNTY WESTWARD...WITH LOW TO MID 40S ACROSS THE
NORTH COUNTRY. THESE LOWS WILL LIKELY OCCUR AROUND MIDNIGHT...WITH
TEMPERATURES RISING LATE. SOME AREAS FROM THE LAKE ERIE SHORE AND
NIAGARA FRONTIER EAST TO ROCHESTER MAY REACH THE LOW TO MID 60S BY
8AM SUNDAY AIDED BY INCREASING SOUTHERLY DOWNSLOPE FLOW.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
THE MAIN STORY DURING THIS PERIOD WILL BE THE DEEP UPPER LEVEL
TROUGH DIGGING ACROSS THE CENTRAL UNITED STATES AND THE SHOT OF
ACCOMPANYING ARCTIC AIR. AS WE OPEN THE PERIOD SUNDAY MORNING AN
ELONGATED SURFACE TROUGH STRETCHING FROM TEXAS TO ONTARIO WILL BE
FOUND ON THE LEADING EDGE OF THIS SHARPENING BAROCLINIC GRADIENT. A
FEW LINGERING SHOWERS AND POSSIBLY A THUNDERSTORM OR TWO ASSOCIATED
WITH SATURDAY NIGHT/S WARM FRONTAL PASSAGE MAY STILL BE IN THE
PROCESS OF LIFTING OUT OF THE NORTH COUNTRY SUNDAY MORNING...BUT
OTHERWISE IT SHOULD BE A DRY AND UNSEASONABLY WARM DAY FOR THE BULK
OF WESTERN AND NORTH-CENTRAL NEW YORK AS THE AREA WILL BE FIRMLY
PLANTED IN THE WARM SECTOR OF THE LOW PRESSURE TO OUR WEST. WITH
850MB TEMPS SURGING TO +12C AND ABUNDANT SUNSHINE ALLOWING FOR A
WELL-MIXED BOUNDARY LAYER...MID 70S SHOULD BE EASILY ATTAINABLE FOR
MOST AREAS WITH THE EXCEPTION OF THE NORTHERN ERIE AND JEFFERSON
COUNTY SHORELINES WHERE THE CHILLY LAKE WATERS WILL MODERATE
TEMPERATURES CONSIDERABLY. ON THE OTHER HAND...WITH SOUTHWESTERLY
WINDS GUSTING UPWARDS OF 30KTS BY THE AFTERNOON THANKS TO THAT
WELL-MIXED BOUNDARY LAYER...DOWNSLOPING COULD PUSH READINGS INTO THE
UPPER 70S ACROSS THE GENESEE VALLEY AND NORTH OF THE FINGER LAKES.
THIS VERY WARM AIRMASS WILL REMAIN IN PLACE THROUGH SUNDAY NIGHT.
WITH DEWPOINTS CLIMBING WELL INTO THE 50S AND LOWS ONLY DROPPING
INTO THE UPPER 50S...IT WILL FEEL VERY MUCH LIKE SUMMER OUTSIDE.
THIS WARMTH WILL PERSIST INTO MONDAY WITH TEMPERATURES ONCE AGAIN
CLIMBING WELL INTO THE 70S BY EARLY AFTERNOON EVEN AS THE STRONG
COLD FRONT MARKING THE BOUNDARY BETWEEN THIS WARM MOIST AIRMASS AND
THE ARCTIC AIR OVER THE UPPER MIDWEST APPROACHES THE LOWER GREAT
LAKES. BY LATE AFTERNOON/EARLY EVENING THE FRONT WILL BE ON OUR
DOORSTEP. WHILE THE AREA WILL BE INCREASINGLY WARM AND UNSTABLE
THROUGH THE DAY...A LACK OF DEEP MOISTURE WILL BE A RESTRICTING
FACTOR ON THE DEVELOPMENT OF ANY CONVECTION UNTIL THE ARRIVAL OF
DEEP MOISTURE ADVECTION ALONG AND JUST AHEAD OF THE FRONTAL
BOUNDARY. HOWEVER AS WE MOVE INTO MONDAY EVENING PWATS ACROSS
WESTERN NY SHOULD SURGE ABOVE AN INCH LEADING TO THE DEVELOPMENT OF
THUNDERSTORMS AHEAD OF THE FRONT AS IT MOVES INTO WESTERN NY. WITH
DECENT DYNAMICS AND WIND FIELDS ALOFT...SOME OF THESE STORMS MAY
FEATURE STRONG WINDS MONDAY EVENING.
THE FRONT WILL SLOWLY MAKE ITS WAY ACROSS WESTERN AND NORTH CENTRAL
NEW YORK MONDAY NIGHT AND TUESDAY. THE COMBINATION OF FAVORABLE
UPPER LEVEL DYNAMICS AND DEEP MOISTURE ADVECTION ALONG WITH THE
ADDED ENHANCEMENT OF A SERIES OF SURFACE WAVES RIPPLING NORTHWARD
ALONG THE RELATIVELY SLOW-MOVING FRONTAL BOUNDARY WILL RESULT IN A
WIDESPREAD SOAKING RAINFALL ACROSS THE REGION WITH A SOLID ONE-
HALF TO ONE INCH OF RAINFALL POSSIBLE. THE COMBINATION OF THIS
RAINFALL AND THE CONSIDERABLE WARMING/THAWING BEFOREHAND ON SUNDAY
AND MONDAY WILL GENERATE THE FLOODING RISK ACROSS THE NORTH
COUNTRY HIGHLIGHTED IN THE HYDROLOGICAL PORTION OF THE DISCUSSION
BELOW...BUT THAT`S NOT ALL. MODEL GUIDANCE IS IN GOOD AGREEMENT
THAT THE FRONTAL BOUNDARY WILL TAKE ON ANAFRONTAL CHARACTERISTICS
AS WARM AIR AHEAD OF THE FRONT RIDES UP THE FRONTAL BOUNDARY
PROPER...AND WITH SUCH COLD AIR MOVING INTO THE REGION BEHIND THE
FRONT THIS MAY LEAD TO A PERIOD OF SNOWFALL AS THE BACK EDGE OF
THE FRONT CROSSES THE AREA FROM EARLY TUESDAY MORNING ONWARDS. A
COUPLE OF INCHES OF SNOW ARE NOT OUT OF THE QUESTION AS ARCTIC AIR
SETTLES ACROSS THE REGION AND TEMPERATURES PLUMMET INTO THE 30S ON
TUESDAY. READINGS WILL TUMBLE EVEN LOWER...INTO THE LOWER 20S WITH
UPPER TEENS OVER HIGHER ELEVATIONS OF THE SOUTHERN TIER AND THE
NORTH COUNTRY AS HIGH PRESSURE SETTLES ACROSS THE REGION TUESDAY
NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AFTER AN UNSETTLED WEEKEND AND START TO THE WEEK...MUCH QUIETER
WEATHER WILL PREVAIL FOR THE LATTER HALF OF THE COMING WEEK AS A
BROAD DOME OF HIGH PRESSURE SHIFTS ACROSS THE GREAT LAKES. ARCTIC
AIR WILL HAVE THE UPPER HAND ON WEDNESDAY IN THE WAKE OF TUESDAY`S
STRONG COLD FRONTAL PASSAGE AND HIGHS ON WEDNESDAY WILL ONLY TOP OUT
IN THE UPPER 30S ACROSS MOST AREAS.
BY WEDNESDAY NIGHT THE CENTER OF THE HIGH MOVES OUT INTO THE GULF OF
SAINT LAWRENCE AND AN UPPER LEVEL SHORTWAVE DIGGING OUT OF THE
PACIFIC NORTHWEST BEGINS TO CARVE OUT A TROUGH ACROSS THE ROCKIES
AND EVENTUALLY THE NATION`S MID-SECTION. WHILE THERE IS STILL
CONSIDERABLE SPREAD AMONG THE MODELS REGARDING THE AMPLITUDE OF THIS
TROUGH...EITHER WAY THE LOWER GREAT LAKES WILL END UP UNDER THE
INFLUENCE OF DOWNSTREAM RIDGING WITH MERIDIONAL FLOW THAT WILL
GRADUALLY ADVECT WARMER AIR ACROSS THE REGION. THIS WILL ALLOW FOR
TEMPERATURES TO REBOUND INTO THE 40S THURSDAY AND THE 50S FRIDAY.
THIS RIDGING WILL ALSO KEEP CONDITIONS DRY AT LEAST THROUGH THURSDAY
NIGHT AND POSSIBLY THROUGH FRIDAY...HOWEVER THAT WILL DEPEND ON THE
SPEED WITH WHICH THE AFOREMENTIONED TROUGHING OVER THE CENTRAL U.S.
MOVES EASTWARD...AN ISSUE STILL IN CONTENTION AMONG THE MODELS AS
PREVIOUSLY MENTIONED.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL FOR THE BULK OF THE AREA FOR THE 06Z TAF
CYCLE. A STRONG YET MOISTURE STARVED MID LEVEL DISTURBANCE WILL
CROSS THE REGION QUICKLY FROM WEST TO EAST THROUGH ABOUT 10Z AND MAY
PRODUCE A FEW SPRINKLES OVER AND NEAR LAKE ONTARIO OUT OF A MID
LEVEL CLOUD DECK. OTHERWISE FOR THE REST OF THE AREA JUST EXPECT
SOME PATCHY CIRRUS.
WIDESPREAD FOG HAS DEVELOPED ACROSS PENNSYLVANIA AND THE CENTRAL
SOUTHERN TIER OF NY. THIS WILL CONTINUE TO EXPAND SLOWLY NORTHWARD
INTO THE WESTERN SOUTHERN TIER WITH WIDESPREAD IFR...ESPECIALLY NEAR
THE PA STATE LINE. THIS FOG SHOULD MIX OUT BY MID MORNING SATURDAY.
FOG MAY ALSO DEVELOP OVER LAKE ERIE LATE TONIGHT...THEN SPREAD
TOWARDS KBUF AND KIAG FOR A FEW HOURS SATURDAY MORNING. THE AIRMASS
IS DRIER THAN IT WAS YESTERDAY MORNING...SO CONFIDENCE IS ONLY
MODERATE AT BEST THAT THIS WILL OCCUR. FOR NOW WILL JUST INCLUDE A
BRIEF TEMPO GROUP WITH IFR UNTIL IT BECOMES MORE APPARENT. IF THIS
DOES DEVELOP...IT MAY PERSIST THROUGH ABOUT MIDDAY BEFORE MIXING OUT.
OTHERWISE FOR THE REST OF SATURDAY EXPECT VFR WITH PASSING THIN
CIRRUS. STRONGER WARM ADVECTION WILL DEVELOP SATURDAY NIGHT WITH
THICKENING AND LOWERING MID LEVEL CLOUDS AND POSSIBLY A FEW WIDELY
SCATTERED SHOWERS. LOW LEVEL WIND SHEAR MAY DEVELOP OVERNIGHT AS A
LOW LEVEL JET CROSSES THE LOWER LAKES.
OUTLOOK...
SUNDAY...MAINLY VFR WITH A CHANCE OF SHOWERS IN THE MORNING.
MONDAY...DETERIORATION TO MVFR LATE WITH RAIN SHOWERS DEVELOPING
ALONG WITH A CHANCE OF THUNDERSTORMS.
TUESDAY...MVFR/IFR WITH RAIN AND SNOW SHOWERS DIMINISHING FROM WEST
TO EAST.
WEDNESDAY...VFR EXPECTED WITH A CHANCE FOR LOCAL IFR FOG.
&&
.MARINE...
HIGH PRESSURE WILL DRIFT SLOWLY AWAY FROM THE REGION TODAY WITH
RELATIVELY LIGHT WINDS CONTINUING. THE WEAK SYNOPTIC SCALE GRADIENT
AND STRONG DIFFERENTIAL HEATING WILL SUPPORT THE DEVELOPMENT OF LAKE
BREEZE CIRCULATIONS TODAY...WITH WINDS BECOMING ONSHORE ALONG ALL
THE LAKESHORES. A WARM FRONT WILL LIFT NORTHEAST ACROSS THE LOWER
LAKES TONIGHT WITH EASTERLY WINDS BECOMING SOUTHERLY AND INCREASING
LATE.
&&
.HYDROLOGY...
HYDROLOGIC CONCERNS GROWING FOR AREAS OF THE EASTERN LAKE ONTARIO
REGION WHERE A SNOWPACK REMAINS IN PLACE. SOME OF THE HIGHEST
ELEVATIONS STILL HAVE A SNOW PACK OF OVER A FOOT. WATER LEVELS
HAVE STEADILY RISEN WITH EVEN SOME OF THE LARGER MAIN STEM RIVERS
IN OR APPROACHING ACTION STAGE. TEMPERATURES ARE EXPECTED TO WARM
ABOVE NORMAL LEVELS FOR THE WEEKEND WHICH WILL CONTINUE THE SNOW
MELTING PROCESS AND CAUSE WATER LEVELS TO CONTINUE TO SLOWLY RISE.
ANY FLOODING ISSUES THIS WEEKEND SHOULD BE ONLY MINOR AND CONFINED
TO THE SMALLER CREEKS AND STREAMS. THIS WOULD BE MORE LIKELY
SUNDAY WHEN DEWPOINTS RISE AND INCREASE THE RATE OF SNOWMELT.
BIGGER HYDROLOGIC CONCERNS DEVELOP DURING THE EARLY TO MID PART OF
NEXT WEEK AS A FRONTAL SYSTEM WORKS ACROSS THE REGION. A DEEP
MOISTURE PLUME RUNNING OUT AHEAD OF THE FRONTAL BOUNDARY COULD
PRODUCE LOCALLY HEAVY RAINFALL IN EXCESS OF AN INCH. THIS RAINFALL
COMBINED WITH ADDITIONAL SNOW MELT WILL BRING A MORE SIGNIFICANT
FLOODING POTENTIAL NOT ONLY ON THE SMALLER CREEKS AND STREAMS...
BUT THE MAIN STEM RIVERS AS WELL. THE POTENTIAL EXISTS FOR THE
BLACK RIVER TO REACH MINOR TO MODERATE FLOOD LEVELS BY WEDNESDAY.
A FLOOD WATCH HAS BEEN ISSUED TO COVER THIS POTENTIAL...PRIMARILY
FOR STREAMS AND RIVERS WHICH HAVE SOURCE REGIONS ON THE TUG HILL
PLATEAU AND THE WESTERN ADIRONDACKS.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...FLOOD WATCH FROM SUNDAY MORNING THROUGH LATE WEDNESDAY NIGHT
FOR NYZ006>008.
DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR NYZ019>021.
MARINE...NONE.
&&
$$
SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...WOOD
LONG TERM...WOOD
AVIATION...HITCHCOCK
MARINE...HITCHCOCK
HYDROLOGY...TMA/HITCHCOCK
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
121 PM EDT SAT APR 12 2014
.SYNOPSIS...
HIGH PRESSURE WILL CONTROL THE WEATHER PATTERN THROUGH EARLY NEXT
WEEK...SUPPORTING DRY AND MILD CONDITIONS. A COLD FRONT WILL MOVE
ACROSS THE AREA TUESDAY...WITH INCREASING CHANCES FOR SHOWERS. HIGH
PRESSURE WILL RETURN TO THE CAROLINAS WEDNESDAY THROUGH FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM SATURDAY...HIGH PRESSURE CENTERED WELL OFF THE
MID-ATLANTIC COAST IS CONTINUING TO EXTEND BACK TOWARDS THE
SOUTHEAST...WITH THE RIDGE AXIS PERSISTING SOUTH OF THE CWA. THIS
AXIS IS EXPECTED TO SHIFT NORTH THROUGH TODAY...IN CONJUNCTION WITH
5H HEIGHTS BUILDING ACROSS THE SOUTHEAST. THIS WILL CREATE A WARM
AND PRIMARILY SUNNY DAY ACROSS THE AREA...WITH HIGHS AWAY FROM THE
BEACHES REACHING INTO THE LOW 80S...UPPER 70S ALONG THE COAST. AS
THE PRESSURE GRADIENT WEAKENS WITH THE NORTHERN ADVANCE OF THE
SURFACE RIDGE AXIS...WINDS WILL EASE...BUT A SEA BREEZE RESULTANT
WILL DRIVE WINDS TO 15 MPH ALONG THE BEACHES. THE HRRR CONTINUES TO
INDICATE AN ISOLATED SHOWER IS POSSIBLE ALONG THE CONVERGENT SEA
BREEZE FRONT THIS AFTN...BUT HAVE KEPT POP AT SILENT AS SOUNDINGS
SUGGEST AN INCREASING SUBSIDENCE INVERSION AND VERY DRY AIR WITHIN
THE SHALLOW UNSTABLE LAYER. STILL...ENHANCE CU IS LIKELY THIS
AFTN/EVE...BUT SHOWERS ARE NOT EXPECTED.
TONIGHT...A GOOD RADIATIONAL COOLING EVENT IS EXPECTED AS WINDS
DECOUPLE AND THE COLUMN REMAINS DRY. PATCHY FOG WILL BECOME
POSSIBLE...ESPECIALLY ACROSS THE EASTERN HALF OF THE CWA WHERE
BETTER DEWPOINT ADVECTION WILL OCCUR THIS AFTN. HOWEVER...AN
INCREASING LLJ WILL LIMIT TOTAL FOG POTENTIAL. INHERITED FORECAST
HAS PATCHY FOG...AND WILL LEAVE UNCHANGED FOR NOW. FOG IS UNLIKELY
TO BE WIDESPREAD HOWEVER...AS MINS DROP ONLY INTO THE MID
50S...LIKELY SEVERAL DEGREES ABOVE CROSSOVER TEMPS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS TO 330 AM SATURDAY...WARM WEATHER WILL CONTINUE WITH
INCREASING CHC OF SHOWERS TOWARD THE END OF THE PERIOD...BY LATE
MONDAY...AS HIGH PRESSURE SLIPS FARTHER OFF SHORE AND A COLD FRONT
APPROACHES THE CAROLINAS FROM THE WEST.
ATLANTIC RIDGE HOLDING ON BUT SHIFTING FARTHER EAST AS A DIGGING
MID TO UPPER TROUGH PUSHES A COLD FRONT EAST. THIS WILL PRODUCE AN
INCREASING SOUTHERLY RETURN FLOW WITH WINDS INITIALLY SOUTHEAST
AROUND 5 TO 10 MPH ON SUNDAY BUT VEERING AROUND TO S TO SW BY
LATE MONDAY AND INCREASING UP TO 15 MPH OR SO AT THE SFC AND UP TO
30 TO 40 KTS IN THE LOW LEVELS. THIS WILL HELP TO INCREASE THE
MOISTURE THROUGH THE COLUMN. THE MID LEVELS WILL STAY DRY UNTIL
LATER ON MONDAY WHEN WE BEGIN TO TAP INTO GREATER GULF MOISTURE.
PCP WATER VALUES WILL INCREASE FROM CLOSER TO A HALF INCH ON SUNDAY
UP TO 1.5 INCHES BY MON LATE AFTN. THE INCREASING MOISTURE AND
LIFT LATE SUNDAY INTO MONDAY WILL CAUSE SOME CLOUDS TO DEVELOP BUT
OVERALL BEST CHC OF PCP WILL COME LATE MON AND MORE SO ON TUES AS
COLD FRONT MAKES IT INTO THE CAROLINAS. EXPECT MAIN FORCING TO
COME IN THE WAY OF CONVERGENCE ASSOCIATED WITH SEA BREEZE AND
LARGER SCALE CONVERGENCE AROUND ATLANTIC RIDGE WITH SOME SHOWERS
FEEDING INTO AREA FROM THE ATLANTIC WATERS. TEMPS WILL REACH UP
AROUND 80 WITH OVERNIGHT LOWS UP NEAR 60 OR ABOVE.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 330 AM SATURDAY...INCREASINGLY MOIST AND UNSTABLE AIR MASS
IN PLACE ON TUESDAY AS COLD FRONT MAKES ITS WAY THROUGH THE
CAROLINAS. DEEP LAYER MOISTURE WILL BE PRESENT WITH PCP WATER
VALUES UP AROUND 1.75 INCHES TUES AFTN. DEWPOINT TEMPS WILL SURGE
INTO THE MID 60S WHILE TEMPS WILL REACH INTO THE 80S. DECENT
DYNAMICS ALOFT INCLUDING A STRONG LLJ...DEEPENING MID TO UPPER
TROUGH AND A STRONG UPPER LEVEL JET WILL COMBINE TO PRODUCE SHWRS
AND THUNDERSTORMS ON TUES AHEAD AND ALONG COLD FRONT. WILL WAIT TO
INCLUDE ANY MENTION OF STRONG TO SVR STORMS BUT AT THIS TIME IT
DOES LOOK LIKE THERE WILL BE SOME STRONG STORMS POSSIBLE
ESPECIALLY OVER INLAND PORTIONS OF CWA.
COLD FRONT SHOULD CROSS THE AREA BY TUES NIGHT WITH COOL AND DRY
HIGH PRESSURE BUILDING IN BEHIND IT. MODELS HINTING AT A WEDGE
SIGNATURE DEVELOPING WHICH MAY LEAVE LOW CLOUDS IN THE FORECAST
FOLLOWING THE FRONT FOR MID WEEK. FOR NOW WILL GO WITH SOME PERIODS
OF CLOUDS DEVELOPING AND OVERALL COOLER TEMPS IN STRONGER NORTH TO
NORTHEAST FLOW BEHIND FRONT FOR WED THROUGH FRI. THERE WILL BE A
GRADUAL WARMING EACH DAY.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 18Z...SOUTH SOUTHWEST FLOW IS EXPECTED AT THE INLAND
TERMINALS...WITH MORE OF A SOUTHERLY COMPONENT AT THE COASTAL
TERMINALS WITH THE RESULTANT...A BIT MORE GUSTY ALONG THE COAST.
TONIGHT...DIMINISHING WINDS WITH A DECENT CHANCE FOR FOG TOWARD
MORNING. BUFKIT SOUNDINGS INDICATE DEEPER LOW LEVEL MOISTURE
INLAND...OFFSET BY HIGHER WINDS AT THE BOUNDARY LAYER...AND COULD
END UP BEING SOME LOW LEVEL STRATUS INSTEAD OF FOG. COULD SEE A
BRIEF BOUT OF IFR RIGHT AT SUNRISE EITHER WAY. SUNDAY...ANOTHER
BEAUTIFUL DAY WITH ONLY SCATTERED CIRRUS. CONTINUED SOUTHWEST FLOW.
EXTENDED OUTLOOK...CHANCE OF SHOWERS AND MVFR CONDITIONS LATE MONDAY
THROUGH TUESDAY WITH SHOWERS AND/OR THUNDERSTORMS ALONG A PASSING
COLD FRONT. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM SATURDAY...RIDGE AXIS EXTENDING TOWARDS THE SOUTHEAST
FROM A HIGH PRESSURE WELL OFF THE MID-ATLANTIC COAST WILL CONTINUE A
WEAK PRESSURE GRADIENT TODAY AND TONIGHT. AS THIS RIDGE AXIS DRIFTS
NORTHWARD TODAY...WINDS WILL BECOME MORE SOUTHEASTERLY...BUT WITH
SPEEDS REMAINING AT OR BELOW 10 KTS. THE EXCEPTION TO THIS WILL BE
ALONG THE IMMEDIATE NEAR-SHORE REGIONS WHERE AN AFTN/EVE SEA BREEZE
WILL ADD 5 OR SO KTS AND A SLIGHTLY MORE SOUTHERLY DIRECTION TO THE
WIND. SEAS WILL BE AROUND 2 FT THROUGH THE PERIOD.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS TO 330 AM SATURDAY...HIGH PRESSURE WILL SHIFT FARTHER OFF THE
COAST AS COLD FRONT NEARS THE CAROLINAS BY LATE MONDAY. THIS WILL
PRODUCE AN INCREASING SOUTHERLY RETURN FLOW THROUGH MONDAY. WINDS
WILL START OUT S-SE REMAINING 10-15 KTS OR BELOW KEEPING SEAS NO
HIGHER THAN 2-3 FT. WINDS AND SEAS WILL THEN INCREASE AND BUILD
ON MONDAY AS THE PRESSURE GRADIENT TIGHTENS WITH APPROACH OF COLD
FRONT. SHOULD SEE SEAS BUILD INTO SCA THRESHOLDS BY LATE MONDAY IN
INCREASING SOUTHERLY WINDS UP TO 20 TO 25 KTS.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS TO 330 AM SATURDAY...SCA CONDITIONS WILL PERSIST AS STRONG
SOUTHERLY FLOW AHEAD OF APPROACHING COLD FRONT REACHES UP NEAR 25
KTS. THIS WILL PUSH SEAS UP NEAR 6 TO 7 FT THROUGH TUES WITH A
SLIGHT DROP AS FRONT CROSSES THE WATERS TUES EVENING INTO EARLY
WED. ONCE THE FRONT CROSSES THE WATERS A STRONG NORTHERLY SURGE
WILL BRING SEAS BACK UP TO 6 TO 8 FT IN THE OUTER WATERS THROUGH
MID WEEK. A PINCHED GRADIENT WILL DEVELOP AS HIGH PRESSURE WEDGES
DOWN THROUGH THE CAROLINAS PRODUCING A PROLONGED PERIOD OF STRONG
N-NE WINDS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...JDW
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...43/17
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
943 AM EDT SAT APR 12 2014
.SYNOPSIS...
HIGH PRESSURE WILL CONTROL THE WEATHER PATTERN THROUGH EARLY NEXT
WEEK...SUPPORTING DRY AND MILD CONDITIONS. A COLD FRONT WILL MOVE
ACROSS THE AREA TUESDAY...WITH INCREASING CHANCES FOR SHOWERS. HIGH
PRESSURE WILL RETURN TO THE CAROLINAS WEDNESDAY THROUGH FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM SATURDAY...HIGH PRESSURE CENTERED WELL OFF THE
MID-ATLANTIC COAST IS CONTINUING TO EXTEND BACK TOWARDS THE
SOUTHEAST...WITH THE RIDGE AXIS PERSISTING SOUTH OF THE CWA. THIS
AXIS IS EXPECTED TO SHIFT NORTH THROUGH TODAY...IN CONJUNCTION WITH
5H HEIGHTS BUILDING ACROSS THE SOUTHEAST. THIS WILL CREATE A WARM
AND PRIMARILY SUNNY DAY ACROSS THE AREA...WITH HIGHS AWAY FROM THE
BEACHES REACHING INTO THE LOW 80S...UPPER 70S ALONG THE COAST. AS
THE PRESSURE GRADIENT WEAKENS WITH THE NORTHERN ADVANCE OF THE
SURFACE RIDGE AXIS...WINDS WILL EASE...BUT A SEA BREEZE RESULTANT
WILL DRIVE WINDS TO 15 MPH ALONG THE BEACHES. THE HRRR CONTINUES TO
INDICATE AN ISOLATED SHOWER IS POSSIBLE ALONG THE CONVERGENT SEA
BREEZE FRONT THIS AFTN...BUT HAVE KEPT POP AT SILENT AS SOUNDINGS
SUGGEST AN INCREASING SUBSIDENCE INVERSION AND VERY DRY AIR WITHIN
THE SHALLOW UNSTABLE LAYER. STILL...ENHANCE CU IS LIKELY THIS
AFTN/EVE...BUT SHOWERS ARE NOT EXPECTED.
TONIGHT...A GOOD RADIATIONAL COOLING EVENT IS EXPECTED AS WINDS
DECOUPLE AND THE COLUMN REMAINS DRY. PATCHY FOG WILL BECOME
POSSIBLE...ESPECIALLY ACROSS THE EASTERN HALF OF THE CWA WHERE
BETTER DEWPOINT ADVECTION WILL OCCUR THIS AFTN. HOWEVER...AN
INCREASING LLJ WILL LIMIT TOTAL FOG POTENTIAL. INHERITED FORECAST
HAS PATCHY FOG...AND WILL LEAVE UNCHANGED FOR NOW. FOG IS UNLIKELY
TO BE WIDESPREAD HOWEVER...AS MINS DROP ONLY INTO THE MID
50S...LIKELY SEVERAL DEGREES ABOVE CROSSOVER TEMPS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS TO 330 AM SATURDAY...WARM WEATHER WILL CONTINUE WITH
INCREASING CHC OF SHOWERS TOWARD THE END OF THE PERIOD...BY LATE
MONDAY...AS HIGH PRESSURE SLIPS FARTHER OFF SHORE AND A COLD FRONT
APPROACHES THE CAROLINAS FROM THE WEST.
ATLANTIC RIDGE HOLDING ON BUT SHIFTING FARTHER EAST AS A DIGGING
MID TO UPPER TROUGH PUSHES A COLD FRONT EAST. THIS WILL PRODUCE AN
INCREASING SOUTHERLY RETURN FLOW WITH WINDS INITIALLY SOUTHEAST
AROUND 5 TO 10 MPH ON SUNDAY BUT VEERING AROUND TO S TO SW BY
LATE MONDAY AND INCREASING UP TO 15 MPH OR SO AT THE SFC AND UP TO
30 TO 40 KTS IN THE LOW LEVELS. THIS WILL HELP TO INCREASE THE
MOISTURE THROUGH THE COLUMN. THE MID LEVELS WILL STAY DRY UNTIL
LATER ON MONDAY WHEN WE BEGIN TO TAP INTO GREATER GULF MOISTURE.
PCP WATER VALUES WILL INCREASE FROM CLOSER TO A HALF INCH ON SUNDAY
UP TO 1.5 INCHES BY MON LATE AFTN. THE INCREASING MOISTURE AND
LIFT LATE SUNDAY INTO MONDAY WILL CAUSE SOME CLOUDS TO DEVELOP BUT
OVERALL BEST CHC OF PCP WILL COME LATE MON AND MORE SO ON TUES AS
COLD FRONT MAKES IT INTO THE CAROLINAS. EXPECT MAIN FORCING TO
COME IN THE WAY OF CONVERGENCE ASSOCIATED WITH SEA BREEZE AND
LARGER SCALE CONVERGENCE AROUND ATLANTIC RIDGE WITH SOME SHOWERS
FEEDING INTO AREA FROM THE ATLANTIC WATERS. TEMPS WILL REACH UP
AROUND 80 WITH OVERNIGHT LOWS UP NEAR 60 OR ABOVE.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 330 AM SATURDAY...INCREASINGLY MOIST AND UNSTABLE AIR MASS
IN PLACE ON TUESDAY AS COLD FRONT MAKES ITS WAY THROUGH THE
CAROLINAS. DEEP LAYER MOISTURE WILL BE PRESENT WITH PCP WATER
VALUES UP AROUND 1.75 INCHES TUES AFTN. DEWPOINT TEMPS WILL SURGE
INTO THE MID 60S WHILE TEMPS WILL REACH INTO THE 80S. DECENT
DYNAMICS ALOFT INCLUDING A STRONG LLJ...DEEPENING MID TO UPPER
TROUGH AND A STRONG UPPER LEVEL JET WILL COMBINE TO PRODUCE SHWRS
AND THUNDERSTORMS ON TUES AHEAD AND ALONG COLD FRONT. WILL WAIT TO
INCLUDE ANY MENTION OF STRONG TO SVR STORMS BUT AT THIS TIME IT
DOES LOOK LIKE THERE WILL BE SOME STRONG STORMS POSSIBLE
ESPECIALLY OVER INLAND PORTIONS OF CWA.
COLD FRONT SHOULD CROSS THE AREA BY TUES NIGHT WITH COOL AND DRY
HIGH PRESSURE BUILDING IN BEHIND IT. MODELS HINTING AT A WEDGE
SIGNATURE DEVELOPING WHICH MAY LEAVE LOW CLOUDS IN THE FORECAST
FOLLOWING THE FRONT FOR MID WEEK. FOR NOW WILL GO WITH SOME PERIODS
OF CLOUDS DEVELOPING AND OVERALL COOLER TEMPS IN STRONGER NORTH TO
NORTHEAST FLOW BEHIND FRONT FOR WED THROUGH FRI. THERE WILL BE A
GRADUAL WARMING EACH DAY.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AS OF 12Z...A WEAK COLD FRONT WILL DROP SOUTHWARD...BUT WILL WEAKEN
AND NOT MOVE INTO THE REGION. HIGH PRESSURE OFFSHORE WILL GIVE US
SOUTHWESTERLY FLOW TODAY...BECOMING SOUTHERLY AND STRONGER ALONG THE
COAST WITH THE RESULTANT. LIGHT WINDS TONIGHT WITH SOME SCATTERED
CIRRUS IN AND OUT OF THE REGION.
EXTENDED OUTLOOK...MORNING FOG POSSIBLE ON SUNDAY. CHANCE OF
SHOWERS AND MVFR CONDITIONS LATE MONDAY INTO TUESDAY WITH SHOWERS
AND/OR THUNDERSTORMS ALONG A PASSING COLD FRONT. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM SATURDAY...RIDGE AXIS EXTENDING TOWARDS THE SOUTHEAST
FROM A HIGH PRESSURE WELL OFF THE MID-ATLANTIC COAST WILL CONTINUE A
WEAK PRESSURE GRADIENT TODAY AND TONIGHT. AS THIS RIDGE AXIS DRIFTS
NORTHWARD TODAY...WINDS WILL BECOME MORE SOUTHEASTERLY...BUT WITH
SPEEDS REMAINING AT OR BELOW 10 KTS. THE EXCEPTION TO THIS WILL BE
ALONG THE IMMEDIATE NEAR-SHORE REGIONS WHERE AN AFTN/EVE SEA BREEZE
WILL ADD 5 OR SO KTS AND A SLIGHTLY MORE SOUTHERLY DIRECTION TO THE
WIND. SEAS WILL BE AROUND 2 FT THROUGH THE PERIOD.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS TO 330 AM SATURDAY...HIGH PRESSURE WILL SHIFT FARTHER OFF THE
COAST AS COLD FRONT NEARS THE CAROLINAS BY LATE MONDAY. THIS WILL
PRODUCE AN INCREASING SOUTHERLY RETURN FLOW THROUGH MONDAY. WINDS
WILL START OUT S-SE REMAINING 10-15 KTS OR BELOW KEEPING SEAS NO
HIGHER THAN 2-3 FT. WINDS AND SEAS WILL THEN INCREASE AND BUILD
ON MONDAY AS THE PRESSURE GRADIENT TIGHTENS WITH APPROACH OF COLD
FRONT. SHOULD SEE SEAS BUILD INTO SCA THRESHOLDS BY LATE MONDAY IN
INCREASING SOUTHERLY WINDS UP TO 20 TO 25 KTS.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS TO 330 AM SATURDAY...SCA CONDITIONS WILL PERSIST AS STRONG
SOUTHERLY FLOW AHEAD OF APPROACHING COLD FRONT REACHES UP NEAR 25
KTS. THIS WILL PUSH SEAS UP NEAR 6 TO 7 FT THROUGH TUES WITH A
SLIGHT DROP AS FRONT CROSSES THE WATERS TUES EVENING INTO EARLY
WED. ONCE THE FRONT CROSSES THE WATERS A STRONG NORTHERLY SURGE
WILL BRING SEAS BACK UP TO 6 TO 8 FT IN THE OUTER WATERS THROUGH
MID WEEK. A PINCHED GRADIENT WILL DEVELOP AS HIGH PRESSURE WEDGES
DOWN THROUGH THE CAROLINAS PRODUCING A PROLONGED PERIOD OF STRONG
N-NE WINDS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...JDW
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...43
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
648 AM EDT SAT APR 12 2014
.SYNOPSIS...
HIGH PRESSURE WILL CONTROL THE WEATHER PATTERN THROUGH EARLY NEXT
WEEK...SUPPORTING DRY AND MILD CONDITIONS. A COLD FRONT WILL MOVE
ACROSS THE AREA TUESDAY...WITH INCREASING CHANCES FOR SHOWERS. HIGH
PRESSURE WILL RETURN TO THE CAROLINAS WEDNESDAY THROUGH FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM SATURDAY...SURFACE HIGH PRESSURE ACROSS THE
WEST-CENTRAL ATLANTIC CONTINUES TO EXTEND A RIDGE AXIS BACK INTO THE
SOUTHEASTERN UNITED STATES. FOR THE PAST TWO DAYS THIS RIDGE WAS
CENTERED ACROSS NORTHERN FLORIDA...BUT THE RIDGE WILL PUSH GRADUALLY
NORTHWARD TODAY AND TONIGHT WITH A SUBSEQUENT BACKING OF OUR
LOW-LEVEL WIND FIELD.
STEEP LAPSE RATES AGAIN TODAY (DRY ADIABATIC UP THROUGH 6000 FEET)
WILL COMBINE WITH A LITTLE HIGHER DEWPOINTS ALONG THE COAST TO
DEVELOP A HEALTHIER CUMULUS FIELD BY EARLY AFTERNOON. THE HRRR MODEL
ACTUALLY SHOWS ISOLATED SHOWERS DEVELOPING 5-25 MILES INLAND FROM
THE BEACHES DURING THE HEAT OF THE DAY. THIS IS INTERESTING SINCE
THE HRRR EXPLICITLY MODELS CONVECTIVE CELLS UNLIKE THE GFS/NAM WHICH
BOTH PARAMETRIZE CONVECTION. VERY LIGHT STEERING FLOW IN THE 750-900
MB LAYER SHOULD PRODUCE LITTLE NET MOVEMENT OF ANY SHOWERS... SO I
AM ONLY INCLUDING A TOKEN 5% POP BETWEEN I-95 AND THE COAST. HIGHS
79-82 ARE EXPECTED INLAND FROM THE BEACHES TODAY.
TONIGHT...GOOD RADIATIONAL COOLING UNDER THE SURFACE RIDGE PLUS
HIGHER DEWPOINTS THAN WE`VE SEEN OVER THE PAST FEW DAYS WILL PRODUCE
PATCHY FOG AND POTENTIALLY SOME LOW STRATUS LATE. LOWS SHOULD FALL
INTO THE MID-UPPER 50S.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS TO 330 AM SATURDAY...WARM WEATHER WILL CONTINUE WITH
INCREASING CHC OF SHOWERS TOWARD THE END OF THE PERIOD...BY LATE
MONDAY...AS HIGH PRESSURE SLIPS FARTHER OFF SHORE AND A COLD FRONT
APPROACHES THE CAROLINAS FROM THE WEST.
ATLANTIC RIDGE HOLDING ON BUT SHIFTING FARTHER EAST AS A DIGGING
MID TO UPPER TROUGH PUSHES A COLD FRONT EAST. THIS WILL PRODUCE AN
INCREASING SOUTHERLY RETURN FLOW WITH WINDS INITIALLY SOUTHEAST
AROUND 5 TO 10 MPH ON SUNDAY BUT VEERING AROUND TO S TO SW BY
LATE MONDAY AND INCREASING UP TO 15 MPH OR SO AT THE SFC AND UP TO
30 TO 40 KTS IN THE LOW LEVELS. THIS WILL HELP TO INCREASE THE
MOISTURE THROUGH THE COLUMN. THE MID LEVELS WILL STAY DRY UNTIL
LATER ON MONDAY WHEN WE BEGIN TO TAP INTO GREATER GULF MOISTURE.
PCP WATER VALUES WILL INCREASE FROM CLOSER TO A HALF INCH ON SUNDAY
UP TO 1.5 INCHES BY MON LATE AFTN. THE INCREASING MOISTURE AND
LIFT LATE SUNDAY INTO MONDAY WILL CAUSE SOME CLOUDS TO DEVELOP BUT
OVERALL BEST CHC OF PCP WILL COME LATE MON AND MORE SO ON TUES AS
COLD FRONT MAKES IT INTO THE CAROLINAS. EXPECT MAIN FORCING TO
COME IN THE WAY OF CONVERGENCE ASSOCIATED WITH SEA BREEZE AND
LARGER SCALE CONVERGENCE AROUND ATLANTIC RIDGE WITH SOME SHOWERS
FEEDING INTO AREA FROM THE ATLANTIC WATERS. TEMPS WILL REACH UP
AROUND 80 WITH OVERNIGHT LOWS UP NEAR 60 OR ABOVE.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 330 AM SATURDAY...INCREASINGLY MOIST AND UNSTABLE AIR MASS
IN PLACE ON TUESDAY AS COLD FRONT MAKES ITS WAY THROUGH THE
CAROLINAS. DEEP LAYER MOISTURE WILL BE PRESENT WITH PCP WATER
VALUES UP AROUND 1.75 INCHES TUES AFTN. DEWPOINT TEMPS WILL SURGE
INTO THE MID 60S WHILE TEMPS WILL REACH INTO THE 80S. DECENT
DYNAMICS ALOFT INCLUDING A STRONG LLJ...DEEPENING MID TO UPPER
TROUGH AND A STRONG UPPER LEVEL JET WILL COMBINE TO PRODUCE SHWRS
AND THUNDERSTORMS ON TUES AHEAD AND ALONG COLD FRONT. WILL WAIT TO
INCLUDE ANY MENTION OF STRONG TO SVR STORMS BUT AT THIS TIME IT
DOES LOOK LIKE THERE WILL BE SOME STRONG STORMS POSSIBLE
ESPECIALLY OVER INLAND PORTIONS OF CWA.
COLD FRONT SHOULD CROSS THE AREA BY TUES NIGHT WITH COOL AND DRY
HIGH PRESSURE BUILDING IN BEHIND IT. MODELS HINTING AT A WEDGE
SIGNATURE DEVELOPING WHICH MAY LEAVE LOW CLOUDS IN THE FORECAST
FOLLOWING THE FRONT FOR MID WEEK. FOR NOW WILL GO WITH SOME PERIODS
OF CLOUDS DEVELOPING AND OVERALL COOLER TEMPS IN STRONGER NORTH TO
NORTHEAST FLOW BEHIND FRONT FOR WED THROUGH FRI. THERE WILL BE A
GRADUAL WARMING EACH DAY.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AS OF 12Z...A WEAK COLD FRONT WILL DROP SOUTHWARD...BUT WILL WEAKEN
AND NOT MOVE INTO THE REGION. HIGH PRESSURE OFFSHORE WILL GIVE US
SOUTHWESTERLY FLOW TODAY...BECOMING SOUTHERLY AND STRONGER ALONG THE
COAST WITH THE RESULTANT. LIGHT WINDS TONIGHT WITH SOME SCATTERED
CIRRUS IN AND OUT OF THE REGION.
EXTENDED OUTLOOK...MORNING FOG POSSIBLE ON SUNDAY. CHANCE OF
SHOWERS AND MVFR CONDITIONS LATE MONDAY INTO TUESDAY WITH SHOWERS
AND/OR THUNDERSTORMS ALONG A PASSING COLD FRONT. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM SATURDAY...ALTHOUGH HIGH PRESSURE IS CENTERED MANY
HUNDREDS OF MILES OFF THE U.S. EAST COAST...A RIDGE AXIS EXTENDING
WEST FROM THIS HIGH LIES ACROSS GEORGIA AND ALABAMA. THIS RIDGE
AXIS SHOULD DRIFT NORTHWARD TONIGHT...WITH LIGHT WINDS GRADUALLY
BACKING MORE SOUTHEASTERLY WITH TIME. OUTSIDE OF THIS AFTERNOON`S
SEABREEZE WIND SPEEDS SHOULD REMAIN UNDER 10 KNOTS...WITH SEAS
ONLY 2 FEET. THE SEABREEZE WILL ADD ABOUT 5 KNOTS NEARSHORE THIS
AFTERNOON INTO THE EARLY EVENING.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS TO 330 AM SATURDAY...HIGH PRESSURE WILL SHIFT FARTHER OFF THE
COAST AS COLD FRONT NEARS THE CAROLINAS BY LATE MONDAY. THIS WILL
PRODUCE AN INCREASING SOUTHERLY RETURN FLOW THROUGH MONDAY. WINDS
WILL START OUT S-SE REMAINING 10-15 KTS OR BELOW KEEPING SEAS NO
HIGHER THAN 2-3 FT. WINDS AND SEAS WILL THEN INCREASE AND BUILD
ON MONDAY AS THE PRESSURE GRADIENT TIGHTENS WITH APPROACH OF COLD
FRONT. SHOULD SEE SEAS BUILD INTO SCA THRESHOLDS BY LATE MONDAY IN
INCREASING SOUTHERLY WINDS UP TO 20 TO 25 KTS.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS TO 330 AM SATURDAY...SCA CONDITIONS WILL PERSIST AS STRONG
SOUTHERLY FLOW AHEAD OF APPROACHING COLD FRONT REACHES UP NEAR 25
KTS. THIS WILL PUSH SEAS UP NEAR 6 TO 7 FT THROUGH TUES WITH A
SLIGHT DROP AS FRONT CROSSES THE WATERS TUES EVENING INTO EARLY
WED. ONCE THE FRONT CROSSES THE WATERS A STRONG NORTHERLY SURGE
WILL BRING SEAS BACK UP TO 6 TO 8 FT IN THE OUTER WATERS THROUGH
MID WEEK. A PINCHED GRADIENT WILL DEVELOP AS HIGH PRESSURE WEDGES
DOWN THROUGH THE CAROLINAS PRODUCING A PROLONGED PERIOD OF STRONG
N-NE WINDS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...43
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
630 AM EDT SAT APR 12 2014
.SYNOPSIS...
HIGH PRESSURE WILL CONTROL THE WEATHER PATTERN THROUGH EARLY NEXT
WEEK...SUPPORTING DRY AND MILD CONDITIONS. A COLD FRONT WILL MOVE
ACROSS THE AREA TUESDAY...WITH INCREASING CHANCES FOR SHOWERS. HIGH
PRESSURE WILL RETURN TO THE CAROLINAS WEDNESDAY THROUGH FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM SATURDAY...SURFACE HIGH PRESSURE ACROSS THE
WEST-CENTRAL ATLANTIC CONTINUES TO EXTEND A RIDGE AXIS BACK INTO THE
SOUTHEASTERN UNITED STATES. FOR THE PAST TWO DAYS THIS RIDGE WAS
CENTERED ACROSS NORTHERN FLORIDA...BUT THE RIDGE WILL PUSH GRADUALLY
NORTHWARD TODAY AND TONIGHT WITH A SUBSEQUENT BACKING OF OUR
LOW-LEVEL WIND FIELD.
STEEP LAPSE RATES AGAIN TODAY (DRY ADIABATIC UP THROUGH 6000 FEET)
WILL COMBINE WITH A LITTLE HIGHER DEWPOINTS ALONG THE COAST TO
DEVELOP A HEALTHIER CUMULUS FIELD BY EARLY AFTERNOON. THE HRRR MODEL
ACTUALLY SHOWS ISOLATED SHOWERS DEVELOPING 5-25 MILES INLAND FROM
THE BEACHES DURING THE HEAT OF THE DAY. THIS IS INTERESTING SINCE
THE HRRR EXPLICITLY MODELS CONVECTIVE CELLS UNLIKE THE GFS/NAM WHICH
BOTH PARAMETRIZE CONVECTION. VERY LIGHT STEERING FLOW IN THE 750-900
MB LAYER SHOULD PRODUCE LITTLE NET MOVEMENT OF ANY SHOWERS... SO I
AM ONLY INCLUDING A TOKEN 5% POP BETWEEN I-95 AND THE COAST. HIGHS
79-82 ARE EXPECTED INLAND FROM THE BEACHES TODAY.
TONIGHT...GOOD RADIATIONAL COOLING UNDER THE SURFACE RIDGE PLUS
HIGHER DEWPOINTS THAN WE`VE SEEN OVER THE PAST FEW DAYS WILL PRODUCE
PATCHY FOG AND POTENTIALLY SOME LOW STRATUS LATE. LOWS SHOULD FALL
INTO THE MID-UPPER 50S.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS TO 330 AM SATURDAY...WARM WEATHER WILL CONTINUE WITH
INCREASING CHC OF SHOWERS TOWARD THE END OF THE PERIOD...BY LATE
MONDAY...AS HIGH PRESSURE SLIPS FARTHER OFF SHORE AND A COLD FRONT
APPROACHES THE CAROLINAS FROM THE WEST.
ATLANTIC RIDGE HOLDING ON BUT SHIFTING FARTHER EAST AS A DIGGING
MID TO UPPER TROUGH PUSHES A COLD FRONT EAST. THIS WILL PRODUCE AN
INCREASING SOUTHERLY RETURN FLOW WITH WINDS INITIALLY SOUTHEAST
AROUND 5 TO 10 MPH ON SUNDAY BUT VEERING AROUND TO S TO SW BY
LATE MONDAY AND INCREASING UP TO 15 MPH OR SO AT THE SFC AND UP TO
30 TO 40 KTS IN THE LOW LEVELS. THIS WILL HELP TO INCREASE THE
MOISTURE THROUGH THE COLUMN. THE MID LEVELS WILL STAY DRY UNTIL
LATER ON MONDAY WHEN WE BEGIN TO TAP INTO GREATER GULF MOISTURE.
PCP WATER VALUES WILL INCREASE FROM CLOSER TO A HALF INCH ON SUNDAY
UP TO 1.5 INCHES BY MON LATE AFTN. THE INCREASING MOISTURE AND
LIFT LATE SUNDAY INTO MONDAY WILL CAUSE SOME CLOUDS TO DEVELOP BUT
OVERALL BEST CHC OF PCP WILL COME LATE MON AND MORE SO ON TUES AS
COLD FRONT MAKES IT INTO THE CAROLINAS. EXPECT MAIN FORCING TO
COME IN THE WAY OF CONVERGENCE ASSOCIATED WITH SEA BREEZE AND
LARGER SCALE CONVERGENCE AROUND ATLANTIC RIDGE WITH SOME SHOWERS
FEEDING INTO AREA FROM THE ATLANTIC WATERS. TEMPS WILL REACH UP
AROUND 80 WITH OVERNIGHT LOWS UP NEAR 60 OR ABOVE.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 330 AM SATURDAY...INCREASINGLY MOIST AND UNSTABLE AIR MASS
IN PLACE ON TUESDAY AS COLD FRONT MAKES ITS WAY THROUGH THE
CAROLINAS. DEEP LAYER MOISTURE WILL BE PRESENT WITH PCP WATER
VALUES UP AROUND 1.75 INCHES TUES AFTN. DEWPOINT TEMPS WILL SURGE
INTO THE MID 60S WHILE TEMPS WILL REACH INTO THE 80S. DECENT
DYNAMICS ALOFT INCLUDING A STRONG LLJ...DEEPENING MID TO UPPER
TROUGH AND A STRONG UPPER LEVEL JET WILL COMBINE TO PRODUCE SHWRS
AND THUNDERSTORMS ON TUES AHEAD AND ALONG COLD FRONT. WILL WAIT TO
INCLUDE ANY MENTION OF STRONG TO SVR STORMS BUT AT THIS TIME IT
DOES LOOK LIKE THERE WILL BE SOME STRONG STORMS POSSIBLE
ESPECIALLY OVER INLAND PORTIONS OF CWA.
COLD FRONT SHOULD CROSS THE AREA BY TUES NIGHT WITH COOL AND DRY
HIGH PRESSURE BUILDING IN BEHIND IT. MODELS HINTING AT A WEDGE
SIGNATURE DEVELOPING WHICH MAY LEAVE LOW CLOUDS IN THE FORECAST
FOLLOWING THE FRONT FOR MID WEEK. FOR NOW WILL GO WITH SOME PERIODS
OF CLOUDS DEVELOPING AND OVERALL COOLER TEMPS IN STRONGER NORTH TO
NORTHEAST FLOW BEHIND FRONT FOR WED THROUGH FRI. THERE WILL BE A
GRADUAL WARMING EACH DAY.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 06Z...HIGH PRESSURE WELL OFFSHORE WILL SUPPORT SOUTHWEST
SURFACE WINDS OVER THE NEXT 24 HOURS. ASIDE FROM CIRRUS AND A LITTLE
ALTOCUMULUS AROUND 7000 FEET SKIES SHOULD REMAIN CLEAR AND VFR
CONDITIONS WILL CONTINUE. AN AFTERNOON SEABREEZE WILL AGAIN PRODUCE
BREEZY CONDITIONS ALONG THE COAST.
EXTENDED OUTLOOK...MORNING FOG POSSIBLE ON SUNDAY. CHANCE OF
SHOWERS AND MVFR CONDITIONS LATE MONDAY INTO TUESDAY WITH SHOWERS
AND/OR THUNDERSTORMS ALONG A PASSING COLD FRONT. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM SATURDAY...ALTHOUGH HIGH PRESSURE IS CENTERED MANY
HUNDREDS OF MILES OFF THE U.S. EAST COAST...A RIDGE AXIS EXTENDING
WEST FROM THIS HIGH LIES ACROSS GEORGIA AND ALABAMA. THIS RIDGE
AXIS SHOULD DRIFT NORTHWARD TONIGHT...WITH LIGHT WINDS GRADUALLY
BACKING MORE SOUTHEASTERLY WITH TIME. OUTSIDE OF THIS AFTERNOON`S
SEABREEZE WIND SPEEDS SHOULD REMAIN UNDER 10 KNOTS...WITH SEAS
ONLY 2 FEET. THE SEABREEZE WILL ADD ABOUT 5 KNOTS NEARSHORE THIS
AFTERNOON INTO THE EARLY EVENING.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS TO 330 AM SATURDAY...HIGH PRESSURE WILL SHIFT FARTHER OFF THE
COAST AS COLD FRONT NEARS THE CAROLINAS BY LATE MONDAY. THIS WILL
PRODUCE AN INCREASING SOUTHERLY RETURN FLOW THROUGH MONDAY. WINDS
WILL START OUT S-SE REMAINING 10-15 KTS OR BELOW KEEPING SEAS NO
HIGHER THAN 2-3 FT. WINDS AND SEAS WILL THEN INCREASE AND BUILD
ON MONDAY AS THE PRESSURE GRADIENT TIGHTENS WITH APPROACH OF COLD
FRONT. SHOULD SEE SEAS BUILD INTO SCA THRESHOLDS BY LATE MONDAY IN
INCREASING SOUTHERLY WINDS UP TO 20 TO 25 KTS.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS TO 330 AM SATURDAY...SCA CONDITIONS WILL PERSIST AS STRONG
SOUTHERLY FLOW AHEAD OF APPROACHING COLD FRONT REACHES UP NEAR 25
KTS. THIS WILL PUSH SEAS UP NEAR 6 TO 7 FT THROUGH TUES WITH A
SLIGHT DROP AS FRONT CROSSES THE WATERS TUES EVENING INTO EARLY
WED. ONCE THE FRONT CROSSES THE WATERS A STRONG NORTHERLY SURGE
WILL BRING SEAS BACK UP TO 6 TO 8 FT IN THE OUTER WATERS THROUGH
MID WEEK. A PINCHED GRADIENT WILL DEVELOP AS HIGH PRESSURE WEDGES
DOWN THROUGH THE CAROLINAS PRODUCING A PROLONGED PERIOD OF STRONG
N-NE WINDS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...TRA/SGL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
357 AM EDT SAT APR 12 2014
.SYNOPSIS...
HIGH PRESSURE WILL CONTROL THE WEATHER PATTERN THROUGH EARLY NEXT
WEEK...SUPPORTING DRY AND MILD CONDITIONS. A COLD FRONT WILL
IMPACT THE AREA TUESDAY...WITH INCREASING CHANCES FOR SHOWERS.
HIGH PRESSURE WILL RETURN TO THE CAROLINAS WEDNESDAY THROUGH
FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 3 AM SATURDAY...SURFACE HIGH PRESSURE ACROSS THE WEST-CENTRAL
ATLANTIC CONTINUES TO EXTEND A RIDGE AXIS BACK INTO THE SOUTHEASTERN
UNITED STATES. FOR THE PAST TWO DAYS THIS RIDGE WAS CENTERED ACROSS
NORTHERN FLORIDA...BUT THE RIDGE WILL PUSH GRADUALLY NORTHWARD TODAY
AND TONIGHT WITH A SUBSEQUENT BACKING OF OUR LOW-LEVEL WIND FIELD.
STEEP LAPSE RATES AGAIN TODAY (DRY ADIABATIC UP THROUGH 6000 FEET)
WILL COMBINE WITH A LITTLE HIGHER DEWPOINTS ALONG THE COAST TO
DEVELOP A HEALTHIER CUMULUS FIELD BY EARLY AFTERNOON. THE HRRR MODEL
ACTUALLY SHOWS ISOLATED SHOWERS DEVELOPING 5-25 MILES INLAND FROM
THE BEACHES DURING THE HEAT OF THE DAY. THIS IS INTERESTING SINCE
THE HRRR EXPLICITLY MODELS CONVECTIVE CELLS UNLIKE THE GFS/NAM WHICH
BOTH PARAMETRIZE CONVECTION. VERY LIGHT STEERING FLOW IN THE 750-900
MB LAYER SHOULD PRODUCE LITTLE NET MOVEMENT OF ANY SHOWERS... SO I
AM ONLY INCLUDING A TOKEN 5-10% POP BETWEEN I-95 AND THE COAST.
HIGHS 79-82 ARE EXPECTED INLAND FROM THE BEACHES TODAY.
TONIGHT...GOOD RADIATIONAL COOLING UNDER THE SURFACE RIDGE PLUS
HIGHER DEWPOINTS THAN WE`VE SEEN OVER THE PAST FEW DAYS WILL PRODUCE
PATCHY FOG AND POTENTIALLY SOME LOW STRATUS LATE. LOWS SHOULD FALL
INTO THE MID-UPPER 50S.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS TO 330 AM SATURDAY...WARM WEATHER WILL CONTINUE WITH
INCREASING CHC OF SHOWERS TOWARD THE END OF THE PERIOD...BY LATE
MONDAY...AS HIGH PRESSURE SLIPS FARTHER OFF SHORE AND A COLD FRONT
APPROACHES THE CAROLINAS FROM THE WEST.
ATLANTIC RIDGE HOLDING ON BUT SHIFTING FARTHER EAST AS A DIGGING
MID TO UPPER TROUGH PUSHES A COLD FRONT EAST. THIS WILL PRODUCE AN
INCREASING SOUTHERLY RETURN FLOW WITH WINDS INITIALLY SOUTHEAST
AROUND 5 TO 10 MPH ON SUNDAY BUT VEERING AROUND TO S TO SW BY
LATE MONDAY AND INCREASING UP TO 15 MPH OR SO AT THE SFC AND UP TO
30 TO 40 KTS IN THE LOW LEVELS. THIS WILL HELP TO INCREASE THE
MOISTURE THROUGH THE COLUMN. THE MID LEVELS WILL STAY DRY UNTIL
LATER ON MONDAY WHEN WE BEGIN TO TAP INTO GREATER GULF MOISTURE.
PCP WATER VALUES WILL INCREASE FROM CLOSER TO A HALF INCH ON SUNDAY
UP TO 1.5 INCHES BY MON LATE AFTN. THE INCREASING MOISTURE AND
LIFT LATE SUNDAY INTO MONDAY WILL CAUSE SOME CLOUDS TO DEVELOP BUT
OVERALL BEST CHC OF PCP WILL COME LATE MON AND MORE SO ON TUES AS
COLD FRONT MAKES IT INTO THE CAROLINAS. EXPECT MAIN FORCING TO
COME IN THE WAY OF CONVERGENCE ASSOCIATED WITH SEA BREEZE AND
LARGER SCALE CONVERGENCE AROUND ATLANTIC RIDGE WITH SOME SHOWERS
FEEDING INTO AREA FROM THE ATLANTIC WATERS. TEMPS WILL REACH UP
AROUND 80 WITH OVERNIGHT LOWS UP NEAR 60 OR ABOVE.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 330 AM SATURDAY...INCREASINGLY MOIST AND UNSTABLE AIR MASS
IN PLACE ON TUESDAY AS COLD FRONT MAKES ITS WAY THROUGH THE
CAROLINAS. DEEP LAYER MOISTURE WILL BE PRESENT WITH PCP WATER
VALUES UP AROUND 1.75 INCHES TUES AFTN. DEWPOINT TEMPS WILL SURGE
INTO THE MID 60S WHILE TEMPS WILL REACH INTO THE 80S. DECENT
DYNAMICS ALOFT INCLUDING A STRONG LLJ...DEEPENING MID TO UPPER
TROUGH AND A STRONG UPPER LEVEL JET WILL COMBINE TO PRODUCE SHWRS
AND THUNDERSTORMS ON TUES AHEAD AND ALONG COLD FRONT. WILL WAIT TO
INCLUDE ANY MENTION OF STRONG TO SVR STORMS BUT AT THIS TIME IT
DOES LOOK LIKE THERE WILL BE SOME STRONG STORMS POSSIBLE
ESPECIALLY OVER INLAND PORTIONS OF CWA.
COLD FRONT SHOULD CROSS THE AREA BY TUES NIGHT WITH COOL AND DRY
HIGH PRESSURE BUILDING IN BEHIND IT. MODELS HINTING AT A WEDGE
SIGNATURE DEVELOPING WHICH MAY LEAVE LOW CLOUDS IN THE FORECAST
FOLLOWING THE FRONT FOR MID WEEK. FOR NOW WILL GO WITH SOME PERIODS
OF CLOUDS DEVELOPING AND OVERALL COOLER TEMPS IN STRONGER NORTH TO
NORTHEAST FLOW BEHIND FRONT FOR WED THROUGH FRI. THERE WILL BE A
GRADUAL WARMING EACH DAY.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 06Z...HIGH PRESSURE WELL OFFSHORE WILL SUPPORT SOUTHWEST
SURFACE WINDS OVER THE NEXT 24 HOURS. ASIDE FROM CIRRUS AND A LITTLE
ALTOCUMULUS AROUND 7000 FEET SKIES SHOULD REMAIN CLEAR AND VFR
CONDITIONS WILL CONTINUE. AN AFTERNOON SEABREEZE WILL AGAIN PRODUCE
BREEZY CONDITIONS ALONG THE COAST.
EXTENDED OUTLOOK...MORNING FOG POSSIBLE ON SUNDAY. CHANCE OF
SHOWERS AND MVFR CONDITIONS LATE MONDAY INTO TUESDAY WITH SHOWERS
AND/OR THUNDERSTORMS ALONG A PASSING COLD FRONT. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 AM SATURDAY...ALTHOUGH HIGH PRESSURE IS CENTERED MANY
HUNDREDS OF MILES OFF THE U.S. EAST COAST...A RIDGE AXIS EXTENDING
WEST FROM THIS HIGH LIES ACROSS GEORGIA AND ALABAMA. THIS RIDGE
AXIS SHOULD DRIFT NORTHWARD TONIGHT...WITH LIGHT WINDS GRADUALLY
BACKING MORE SOUTHEASTERLY WITH TIME. OUTSIDE OF THIS AFTERNOON`S
SEABREEZE WIND SPEEDS SHOULD REMAIN UNDER 10 KNOTS...WITH SEAS
ONLY 2 FEET. THE SEABREEZE WILL ADD ABOUT 5 KNOTS NEARSHORE THIS
AFTERNOON INTO THE EARLY EVENING.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS TO 330 AM SATURDAY...HIGH PRESSURE WILL SHIFT FARTHER OFF THE
COAST AS COLD FRONT NEARS THE CAROLINAS BY LATE MONDAY. THIS WILL
PRODUCE AN INCREASING SOUTHERLY RETURN FLOW THROUGH MONDAY. WINDS
WILL START OUT S-SE REMAINING 10-15 KTS OR BELOW KEEPING SEAS NO
HIGHER THAN 2-3 FT. WINDS AND SEAS WILL THEN INCREASE AND BUILD
ON MONDAY AS THE PRESSURE GRADIENT TIGHTENS WITH APPROACH OF COLD
FRONT. SHOULD SEE SEAS BUILD INTO SCA THRESHOLDS BY LATE MONDAY IN
INCREASING SOUTHERLY WINDS UP TO 20 TO 25 KTS.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS TO 330 AM SATURDAY...SCA CONDITIONS WILL PERSIST AS STRONG
SOUTHERLY FLOW AHEAD OF APPROACHING COLD FRONT REACHES UP NEAR 25
KTS. THIS WILL PUSH SEAS UP NEAR 6 TO 7 FT THROUGH TUES WITH A
SLIGHT DROP AS FRONT CROSSES THE WATERS TUES EVENING INTO EARLY
WED. ONCE THE FRONT CROSSES THE WATERS A STRONG NORTHERLY SURGE
WILL BRING SEAS BACK UP TO 6 TO 8 FT IN THE OUTER WATERS THROUGH
MID WEEK. A PINCHED GRADIENT WILL DEVELOP AS HIGH PRESSURE WEDGES
DOWN THROUGH THE CAROLINAS PRODUCING A PROLONGED PERIOD OF STRONG
N-NE WINDS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...TRA/SGL
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
626 PM EDT SAT APR 12 2014
.SYNOPSIS...
A WARM FRONT WILL MOVE NORTH OF THE FORECAST AREA THIS EVENING.
A STRONG COLD FRONT WILL BEGIN TO MOVE TOWARDS THE REGION ON SUNDAY.
THIS FRONT WILL PUSH ACROSS NORTHERN OHIO AND NORTHWESTERN
PENNSYLVANIA MONDAY AFTERNOON AND EVENING USHERING MUCH COLDER AIR
INTO THE REGION.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
THE BEST INFLOW FOR SHOWER/THUNDERSTORM DEVELOPMENT REMAINS WELL
TO THE WEST. WE CAN GET THROUGH THE EARLY EVENING HOURS WITH NOT
MUCH RISK OTHER THAN A SPRINKLE. THE EARLY EVENING FORECAST UPDATE
HAS TRENDED THE HOURLY POP/WX AND SKY COVER IN THIS DIRECTION
OTHERWISE NO SIGNIFICANT CHANGES TO THE REMAINDER OF THE
FORECAST.
ORIGINAL "TONIGHT" DISCUSSION...
THE FORECAST TONIGHT APPEARS RELATIVELY STRAIGHT FORWARD BUT IT IS
NOT. THE CONCERN IS THE MOVEMENT OF THE WARM FRONT AND THE LOW
LEVEL JET TO THE WEST. CONVECTION HAD FIRED ON THE HEAD OF THE LOW
LEVEL JET NEAR THE WARM FRONT OVER NORTHERN ILLINOIS AND WISCONSIN
THIS AFTERNOON. THE CONVECTION IS MOVING EAST AND APPEARS THAT IT
WILL STAY NORTH OF THE FORECAST AREA. THE CONCERN IS OVERNIGHT
WHEN THE LOW LEVEL JET MOVES EAST. THE HEAD OF THE JET WILL MOVE
INTO NORTHERN INDIANA OVERNIGHT. IT IS POSSIBLE SOME CONVECTION
COULD FIRE IN THIS AREA AND MOVE EAST. THE GFS IS "ALL IN" ON THIS
SCENARIO AND PUTTING REALLY HIGH POPS OVER THE FORECAST AREA
TONIGHT. I AM NOT AS SOLD ON THAT SOLUTION AND I AM LEANING MORE
TOWARD THE NAM SOLUTION THAT KEEPS THE CONVECTION NORTH OF THE
FORECAST AREA. THE CURRENT FORECAST HAS SLIGHT CHANCE POPS
OVERNIGHT FOR THE VERY NORTHERN AREAS OF THE FORECAST AREA. I AM
NOT CONVINCED THE GFS IS COMPLETELY RIGHT BUT I AM NOT CONFIDENT
ENOUGH IN THE NAM TO COMPLETELY REMOVE THE POPS. THE HRRR MODEL
KEEPS THE PRECIPITATION NORTH AS WELL. I WILL KEEP THE SLGHT CHC
FOR THE NORTH OVERNIGHT. WINDS ARE CURRENTLY GUSTING NEAR 30MPH.
THESE GUSTY WINDS WILL CONTINUE THROUGH THE EVENING BUT SHOULD
DECREASE SLIGHTLY OVERNIGHT AS WE DECOUPLE.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY NIGHT/...
A COMPLEX SITUATION FOR THE SHORT TERM PERIOD SUNDAY THROUGH
WEDNESDAY. A VIGOROUS COLD FRONT WILL DOMINATE THE FOCUS OF THE
WEATHER FORECAST. THE MODELS ARE IN FAIRLY GOOD AGREEMENT THAT THE
FRONT WILL MOVE ACROSS THE AREA 18Z-06Z MON-TUE. TIMING OF THE
PRECIPITATION WITH THE FRONT IS SOMEWHAT DIFFICULT PARTICULARLY FOR
NORTHWEST OHIO. A STRONG 850MB JET WILL SETUP OVER INDIANA AND NW
OHIO ON SUNDAY AND REMAIN IN VARIOUS STATES UNTIL THE FRONT PUSHES
THE JET MAX EAST MONDAY NIGHT. THE INTERACTION OF THIS JET WITH THE
WARM FRONT IS CONCERNING. WHILE I THINK THE BULK OF THE
PRECIPITATION WILL REMAIN NORTH OF THE FORECAST AREA...I AM NOT
CONFIDENT ENOUGH TO KEEP A DRY FORECAST. MARGINAL INSTABILITY AND
DEWPOINTS IN THE 50S ARE ENOUGH FOR ME TO KEEP PRECIPITATION IN THE
FORECAST FOR NW OHIO ON SUNDAY AND SUNDAY NIGHT. I WILL BEGIN TO
EXPAND THE PRECIPITATION EASTWARD ON MONDAY MORNING WITH ALL AREAS
FORECAST TO HAVE WIDESPREAD PRECIPITATION MONDAY AFTERNOON. THE LOW
LEVEL DYNAMICS WITH THIS FRONT ARE IMPRESSIVE. THE THERMAL FORCING
WILL BE STRONG ON MONDAY AFTERNOON AND CONVECTION IS EXPECTED.
CURRENTLY...THE MODELS HAVE LOW AMOUNTS OF INSTABILITY OVER THE REGION
MONDAY AFTERNOON AND SPC DOES NOT HAVE THE AREA IN ANY TYPE OF
SEVERE CONVECTIVE OUTLOOK EXCEPT FOR GENERAL THUNDER. WE WILL NEED
TO MONITOR THE TRENDS AS A SLIGHT INCREASE IN INSTABILITY COULD MEAN
MORE INTENSE CONVECTION MONDAY AFTERNOON.
STRONG COLD AIR ADVECTION WILL OCCUR BEHIND THE FRONT MONDAY NIGHT
AND TUESDAY. WITH 850MB TEMPS DROPPING BELOW -10C PRECIPITATION
SHOULD TRANSITION TO A MIX OF RAIN AND SNOW AND THEN SNOW SHOWERS
MONDAY NIGHT. SNOW SHOWERS WILL CONTINUE ON TUESDAY BUT MAY MIX
WITH RAIN DUE TO DAY TIME HEATING. CONDITIONS ARE MARGINAL FOR LAKE
ENHANCED PRECIPITATION TUESDAY AFTERNOON AND TUESDAY NIGHT. AT THIS
TIME I WILL KEEP THE MENTION OF PRECIPITATION IN THESE AREAS THROUGH
TUESDAY NIGHT. THE 850MB THERMAL TROF DOES NOT PAST EAST OF THE
AREA UNTIL 06Z WED. TEMPERATURE FORECASTS WILL BE TOUGH. WE WILL
SEE A NON-DIURNAL TREND LATE MONDAY AFTERNOON AS THE FRONT MOVES
THROUGH THE AREA. HIGHS ON TUESDAY WILL BE TRICKY AS WELL WITH
STRONG COLD AIR ADVECTION.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
HE HIGH THAT HELPED TO PUSH THE UNSEASONABLY COLD AIR INTO THE
AREA WILL SHIFT NE OF THE AREA WED BUT SHOULD CONTINUE TO INFLUENCE
THE WEATHER THRU THU NIGHT. THIS SHOULD MEAN DRY CONDITIONS INTO THU
NIGHT. AN INCREASING CHANCE FOR SHRA LOOKS TO DEVELOP FRI INTO FRI
NIGHT. THE MODELS START TO DIFFER MORE BY FRI SO THE SITUATION BY
THEN IS MORE IN QUESTION AND EVEN MORE SO BY SAT. WILL CONTINUE THE
CHANCE FOR SHRA ON SAT.
TEMPS WILL SLOWLY MODERATE BACK CLOSE TO NORMAL BY FRI AND
SAT...ALTHOUGH SAT COULD CHANGE IF A WEAK COLD FRONT MOVES THRU AND
TURNS THE FLOW OFF OF THE CHILLY LAKE.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
PATCHY HIGH AND MID LEVEL CLOUDS WILL MOVE ESE ACROSS THE AREA INTO
TONIGHT THEN LOWER LEVEL MOISTURE ARRIVES SO CIGS SHOULD DROP TO
MVFR LATE TONIGHT INTO SUN MORNING ALTHOUGH CAK...YNG AND ERI MAY
HOLD OFF ON THE MVFR. A FEW SHRA ARE POSSIBLE NEAR LAKE ERIE THIS
EVENING AS DYING CONVECTION UPSTREAM WASHES OUT AROUND THE LAKE ERIE
AREA. SOME MVFR FOG IS POSSIBLE TOWARD THE END OF THE NIGHT MAINLY
WHERE THE MVFR CIGS DEVELOP. SOME IMPROVEMENT IN THE MVFR SHOULD
TAKE PLACE BY MIDDAY AS THE AIR MASS MIXES MORE...THUS ALLOWING THE
FOG TO DISSIPATE AND THE MVFR CIGS TO TRY AND LIFT SOME.
SSW WINDS GUSTING TO 15 TO 20 KNOTS WILL SETTLE DOWN SOME WITH
NIGHTFALL THEN PICK BACK UP SUN MORNING. HOWEVER...ERI WILL LIKELY
PICK BACK UP DURING THE SECOND HALF OF NIGHT DUE TO DOWN SLOPE
ACCELERATION.
.OUTLOOK...NON VFR LIKELY WITH THE PASSAGE OF A STRONG COLD
FRONT ON MONDAY.
&&
.MARINE...
MAINLY SOUTH WINDS SHOULD GRADUALLY INCREASE TO ABOUT 15 TO 25 KNOTS
TONIGHT INTO MON...BRIEFLY DIMINISH AS COLD FRONT PASSES LATER MON
WHILE VEERING TO THE NW THEN INCREASING BACK TO 15 TO 25 KNOTS MON
NIGHT BEFORE DIMINISHING LATE TUE AND TUE NIGHT AS HIGH PRESSURE
MOVES OVER THE LAKE. WINDS AT THE SHORELINE MAY BE NEAR 30 KNOTS AT
TIMES MON MORNING BUT THE COLDER WATER TEMPS SHOULD LIMIT THE WINDS
FURTHER OFFSHORE. A SCA WILL LIKELY BE ISSUED FOR LATE SUN NIGHT AND
MON AND MAY ALSO BE NEEDED ON SUN. THE HIGH OVER THE LAKE TUE NIGHT
WILL LIFT NE OF THE LAKES WED LEADING TO E TO NE WINDS ABOUT 10 TO
15 KNOTS WED INTO THU.
THE STRONGER WINDS AND WARMER TEMPS AHEAD OF THE COLD FRONT WILL
CAUSE CONTINUED BREAKUP OF THE ICE FIELDS ON THE LAKE BUT MAY ALSO
CAUSE OPEN TRACKS TO CLOSE ON THE NE PART OF THE LAKE AS THE ICE
SHIFTS IN THAT DIRECTION.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GARNET/KOSARIK
NEAR TERM...GARNET/KOSARIK
SHORT TERM...GARNET
LONG TERM...ADAMS
AVIATION...ADAMS
MARINE...ADAMS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
311 PM EDT SAT APR 12 2014
.SYNOPSIS...
A WARM FRONT WILL MOVE NORTH OF THE FORECAST AREA THIS EVENING.
A STRONG COLD FRONT WILL BEGIN TO MOVE TOWARDS THE REGION ON SUNDAY.
THIS FRONT WILL PUSH ACROSS NORTHERN OHIO AND NORTHWESTERN
PENNSYLVANIA MONDAY AFTERNOON AND EVENING USHERING MUCH COLDER AIR
INTO THE REGION.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
THE FORECAST TONIGHT APPEARS RELATIVELY STRAIGHT FORWARD BUT IT IS
NOT. THE CONCERN IS THE MOVEMENT OF THE WARM FRONT AND THE LOW LEVEL
JET TO THE WEST. CONVECTION HAD FIRED ON THE HEAD OF THE LOW LEVEL
JET NEAR THE WARM FRONT OVER NORTHERN ILLINOIS AND WISCONSIN THIS
AFTERNOON. THE CONVECTION IS MOVING EAST AND APPEARS THAT IT WILL
STAY NORTH OF THE FORECAST AREA. THE CONCERN IS OVERNIGHT WHEN THE
LOW LEVEL JET MOVES EAST. THE HEAD OF THE JET WILL MOVE INTO
NORTHERN INDIANA OVERNIGHT. IT IS POSSIBLE SOME CONVECTION COULD
FIRE IN THIS AREA AND MOVE EAST. THE GFS IS "ALL IN" ON THIS
SCENARIO AND PUTTING REALLY HIGH POPS OVER THE FORECAST AREA
TONIGHT. I AM NOT AS SOLD ON THAT SOLUTION AND I AM LEANING MORE
TOWARD THE NAM SOLUTION THAT KEEPS THE CONVECTION NORTH OF THE
FORECAST AREA. THE CURRENT FORECAST HAS SLIGHT CHANCE POPS
OVERNIGHT FOR THE VERY NORTHERN AREAS OF THE FORECAST AREA. I AM
NOT CONVINCED THE GFS IS COMPLETELY RIGHT BUT I AM NOT CONFIDENT
ENOUGH IN THE NAM TO COMPLETELY REMOVE THE POPS. THE HRRR MODEL
KEEPS THE PRECIPITATION NORTH AS WELL. I WILL KEEP THE SLGHT CHC FOR
THE NORTH OVERNIGHT. WINDS ARE CURRENTLY GUSTING NEAR 30MPH. THESE
GUSTY WINDS WILL CONTINUE THROUGH THE EVENING BUT SHOULD DECREASE
SLIGHTLY OVERNIGHT AS WE DECOUPLE.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY NIGHT/...
A COMPLEX SITUATION FOR THE SHORT TERM PERIOD SUNDAY THROUGH
WEDNESDAY. A VIGOROUS COLD FRONT WILL DOMINATE THE FOCUS OF THE
WEATHER FORECAST. THE MODELS ARE IN FAIRLY GOOD AGREEMENT THAT THE
FRONT WILL MOVE ACROSS THE AREA 18Z-06Z MON-TUE. TIMING OF THE
PRECIPITATION WITH THE FRONT IS SOMEWHAT DIFFICULT PARTICULARLY FOR
NORTHWEST OHIO. A STRONG 850MB JET WILL SETUP OVER INDIANA AND NW
OHIO ON SUNDAY AND REMAIN IN VARIOUS STATES UNTIL THE FRONT PUSHES
THE JET MAX EAST MONDAY NIGHT. THE INTERACTION OF THIS JET WITH THE
WARM FRONT IS CONCERNING. WHILE I THINK THE BULK OF THE
PRECIPITATION WILL REMAIN NORTH OF THE FORECAST AREA...I AM NOT
CONFIDENT ENOUGH TO KEEP A DRY FORECAST. MARGINAL INSTABILITY AND
DEWPOINTS IN THE 50S ARE ENOUGH FOR ME TO KEEP PRECIPITATION IN THE
FORECAST FOR NW OHIO ON SUNDAY AND SUNDAY NIGHT. I WILL BEGIN TO
EXPAND THE PRECIPITATION EASTWARD ON MONDAY MORNING WITH ALL AREAS
FORECAST TO HAVE WIDESPREAD PRECIPITATION MONDAY AFTERNOON. THE LOW
LEVEL DYNAMICS WITH THIS FRONT ARE IMPRESSIVE. THE THERMAL FORCING
WILL BE STRONG ON MONDAY AFTERNOON AND CONVECTION IS EXPECTED.
CURRENTLY...THE MODELS HAVE LOW AMOUNTS OF INSTABILITY OVER THE REGION
MONDAY AFTERNOON AND SPC DOES NOT HAVE THE AREA IN ANY TYPE OF
SEVERE CONVECTIVE OUTLOOK EXCEPT FOR GENERAL THUNDER. WE WILL NEED
TO MONITOR THE TRENDS AS A SLIGHT INCREASE IN INSTABILITY COULD MEAN
MORE INTENSE CONVECTION MONDAY AFTERNOON.
STRONG COLD AIR ADVECTION WILL OCCUR BEHIND THE FRONT MONDAY NIGHT
AND TUESDAY. WITH 850MB TEMPS DROPPING BELOW -10C PRECIPITATION
SHOULD TRANSITION TO A MIX OF RAIN AND SNOW AND THEN SNOW SHOWERS
MONDAY NIGHT. SNOW SHOWERS WILL CONTINUE ON TUESDAY BUT MAY MIX
WITH RAIN DUE TO DAY TIME HEATING. CONDITIONS ARE MARGINAL FOR LAKE
ENHANCED PRECIPITATION TUESDAY AFTERNOON AND TUESDAY NIGHT. AT THIS
TIME I WILL KEEP THE MENTION OF PRECIPITATION IN THESE AREAS THROUGH
TUESDAY NIGHT. THE 850MB THERMAL TROF DOES NOT PAST EAST OF THE
AREA UNTIL 06Z WED. TEMPERATURE FORECASTS WILL BE TOUGH. WE WILL
SEE A NON-DIURNAL TREND LATE MONDAY AFTERNOON AS THE FRONT MOVES
THROUGH THE AREA. HIGHS ON TUESDAY WILL BE TRICKY AS WELL WITH
STRONG COLD AIR ADVECTION.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
HE HIGH THAT HELPED TO PUSH THE UNSEASONABLY COLD AIR INTO THE
AREA WILL SHIFT NE OF THE AREA WED BUT SHOULD CONTINUE TO INFLUENCE
THE WEATHER THRU THU NIGHT. THIS SHOULD MEAN DRY CONDITIONS INTO THU
NIGHT. AN INCREASING CHANCE FOR SHRA LOOKS TO DEVELOP FRI INTO FRI
NIGHT. THE MODELS START TO DIFFER MORE BY FRI SO THE SITUATION BY
THEN IS MORE IN QUESTION AND EVEN MORE SO BY SAT. WILL CONTINUE THE
CHANCE FOR SHRA ON SAT.
TEMPS WILL SLOWLY MODERATE BACK CLOSE TO NORMAL BY FRI AND
SAT...ALTHOUGH SAT COULD CHANGE IF A WEAK COLD FRONT MOVES THRU AND
TURNS THE FLOW OFF OF THE CHILLY LAKE.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
PATCHY HIGH AND MID LEVEL CLOUDS WILL MOVE ESE ACROSS THE AREA INTO
TONIGHT THEN LOWER LEVEL MOISTURE ARRIVES SO CIGS SHOULD DROP TO
MVFR LATE TONIGHT INTO SUN MORNING ALTHOUGH CAK...YNG AND ERI MAY
HOLD OFF ON THE MVFR. A FEW SHRA ARE POSSIBLE NEAR LAKE ERIE THIS
EVENING AS DYING CONVECTION UPSTREAM WASHES OUT AROUND THE LAKE ERIE
AREA. SOME MVFR FOG IS POSSIBLE TOWARD THE END OF THE NIGHT MAINLY
WHERE THE MVFR CIGS DEVELOP. SOME IMPROVEMENT IN THE MVFR SHOULD
TAKE PLACE BY MIDDAY AS THE AIRMASS MIXES MORE...THUS ALLOWING THE
FOG TO DISSIPATE AND THE MVFR CIGS TO TRY AND LIFT SOME.
SSW WINDS GUSTING TO 15 TO 20 KNOTS WILL SETTLE DOWN SOME WITH
NIGHTFALL THEN PICK BACK UP SUN MORNING. HOWEVER...ERI WILL LIKELY
PICK BACK UP DURING THE SECOND HALF OF NIGHT DUE TO DOWNSLOPE
ACCELERATION.
.OUTLOOK...NON VFR LIKELY WITH THE PASSAGE OF A STRONG COLD
FRONT ON MONDAY.
&&
.MARINE...
MAINLY SOUTH WINDS SHOULD GRADUALLY INCREASE TO ABOUT 15 TO 25 KNOTS
TONIGHT INTO MON...BRIEFLY DIMINISH AS COLD FRONT PASSES LATER MON
WHILE VEERING TO THE NW THEN INCREASING BACK TO 15 TO 25 KNOTS MON
NIGHT BEFORE DIMINISHING LATE TUE AND TUE NIGHT AS HIGH PRESSURE
MOVES OVER THE LAKE. WINDS AT THE SHORELINE MAY BE NEAR 30 KNOTS AT
TIMES MON MORNING BUT THE COLDER WARER TEMPS SHOULD LIMIT THE WINDS
FURTHER OFFSHORE. A SCA WILL LIKELY BE ISSUED FOR LATE SUN NIGHT AND
MON AND MAY ALSO BE NEEDED ON SUN. THE HIGH OVER THE LAKE TUE NIGHT
WILL LIFT NE OF THE LAKES WED LEADING TO E TO NE WINDS ABOUT 10 TO
15 KNOTS WED INTO THU.
THE STRONGER WINDS AND WARMER TEMPS AHEAD OF THE COLD FRONT WILL
CAUSE CONTINUED BREAKUP OF THE ICE FIELDS ON THE LAKE BUT MAY ALSO
CAUSE OPEN TRACKS TO CLOSE ON THE NE PART OF THE LAKE AS THE ICE
SHIFTS IN THAT DIRECTION.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GARNET
NEAR TERM...GARNET
SHORT TERM...GARNET
LONG TERM...ADAMS
AVIATION...ADAMS
MARINE...ADAMS
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
144 PM EDT SAT APR 12 2014
.SYNOPSIS...
A WEAK WARM FRONT WILL LIFT NORTH THROUGH THIS EVENING. SOUTHERLY
FLOW THROUGH THE WEEKEND WITH WARM SUMMER LIKE TEMPERATURES. NEXT
FRONT MONDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
SENT AN UPDATE FOR SMALL POPS DUE TO DIURNAL HEATING IN THE WARM
SECTOR OF THE WARM FRONT LIFTING NORTH ACROSS CENTRAL CWA. BELIEVE
SOME PCPN OUT OF POPCORN CU FIELD COULD MEASURE BUT ACCUMULATIONS
WILL BE MORE LIKE A HIT OR MISS AND VERY LIGHT. THE HRRR AND NAM
MODELS SHOW SMALL AREAS OF QPF WITH THIS FEATURE MOVING NORTH AND
DISSIPATING JUST BEFORE SUNSET. UPDATED DEWPOINTS AS THERE IS A 10
DEGREES GRADIENT ALONG THE WARM FRONT WHICH SLOWLY DRIFTS NORTH
THROUGH THIS EVENING.
PREVIOUS DISCUSSION BELOW...
UPDATED SKIES AS EXPECTED DIURNAL CU DEVELOPING ACROSS THE
WESTERN SLOPES AND EASTERN MOUNTAINS THIS AFTERNOON.
ALSO...ADJUSTED DEWPOINTS INCREASING TO NOON...BECOMING STEADY OR
DECREASING SOME DUE TO MIXING...THEN RECOVERING BY SUNSET. REST OF
FORECAST REMAINS REPRESENTATIVE FOR DRY CONDITIONS.
PREVIOUS DISCUSSION BELOW...
HI RES MODELS PICK UP ON SHORT WAVE CURRENTLY OUT OVER THE
MISSISSIPPI VALLEY AND TAKE IT EASTWARD ACROSS THE AREA THIS
AFTERNOON. THIS FEATURE SHOULD REMAIN MOSTLY INACTIVE PRECIP
WISE...DESPITE WEAK WARM FRONT...DUE LACK OF DEEPER MOISTURE AND
INSTABILITY. EXCEPTION MAY BE ON EAST FACING SLOPES OF THE
NORTHERN MOUNTAINS THIS AFTERNOON WHERE SOUTHEAST FLOW UPSLOPE
FACTOR MAY JUST BE ENOUGH TO TRIGGER A SHOWER. WILL INTRODUCE
SLIGHT CHC POPS FOR A SHOWER ON EAST FACING SLOPES OF THE NORTHERN
MOUNTAINS. OTHERWISE...OCCASIONAL CLOUDS.
PREVIOUS DISCUSSION...
A TRANQUIL PERIOD BETWEEN SIGNIFICANT WEATHER SYSTEMS. WEAK HIGH
PRESSURE OVERHEAD WILL SLIDE EAST TODAY...ALLOWING A WEAK WARM FRONT
TO LIFT NORTH ACROSS THE AREA THIS AFTERNOON. GOOD AGREEMENT AMONG
THE MODELS ON THE MASS FIELDS. TRAPPED LOW LEVEL MOISTURE UNDER THIS
HIGH HAS ALLOWED FIRST SIGNIFICANT WARM SEASON EARLY MORNING FOG TO
FORM IN SOME RIVER VALLEYS...BUT WILL BURN OFF BY MID MORNING WITH
HEATING AND MIXING. UNTIL THEN...THERE ARE SOME NOCTURNAL LOW
STRATUS SHOWING UP IN THE NORTH AND EAST...WHILE SOME MID CLOUDS
LINGER ACROSS THE SOUTH FROM AN UPPER DISTURBANCE PASSING TO OUR
SOUTH. SO WHILE IT IS EXPECTED TO REMAIN DRY OVERNIGHT...EARLY
MORNING CLOUDS WILL BE AN ISSUE FOR HOW MUCH EARLY MORNING FOG FORMS
AND IS MAINTAINED. EXPECT ENOUGH STARS...WITH SOME BREAKS IN THE
CLOUDS NORTHEAST AND SOUTH...TO HAVE RIVER AND VALLEY FOG EARLY THIS
MORNING...BEFORE BURNING OFF.
IN ANY CASE...WITH LACK OF DEEPER MOISTURE AND UPPER SUPPORT FOR
WARM FRONT...ONLY SOME CLOUDS ARE EXPECTED WITH THE WARM FRONT
TODAY...MAINLY NORTH AND WEST. WILL NOT PLAY ON INSTABILITY WITH
LACK OF DEEPER MOISTURE...NOR WEAK SOUTHEAST UPSLOPE FLOW...FOR ANY
POPS TODAY. WILL KEEP DRY. AS THE HIGH SHIFTS EAST TODAY AND THE
WARM FRONT LIFTS NORTH OF THE AREA THIS AFTERNOON...ENOUGH SUNSHINE
AND SOUTHERLY BREEZES WILL ALLOW MAX TEMPERATURES TODAY TO REACH
NEAR 80 IN MANY AREAS. MOSTLY CLEAR TONIGHT...BUT SOUTHERLY BREEZES
WILL LIKELY RESULT IN LESS FOG FORMATION AND A MILD NIGHT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
NO WHOLESALE CHANGES FOR THE SHORT TERM FORECAST TONIGHT AS MODELS
ARE HOLDING TRUE TO THE PATTERN FOR SEVERAL FORECAST RUNS NOW.
FIGURE THERE WILL END UP BEING SOME MINOR TIMING ISSUES...BUT THE
MAIN FEATURE WILL BE THE COLD FRONT AND ITS ASSOCIATED CONVECTION
FOR MONDAY AND MONDAY NIGHT. STILL HAVE TO GIVE A BROAD TIME RANGE
FOR THE POPS...ALTHOUGH THE 15Z START TIME OVER THE WESTERN ZONES
WITH THE LOW END POPS MAY PROVE TO BE A TAD QUICK. MODELS ARE STILL
ON BOARD WITH A LOW PRESSURE CENTER RIDING NORTH ALONG THE FRONT
AFTER PASSAGE WHICH WILL KEEP THE PRECIPITATION CHANCES ALIVE INTO
EARLY TUESDAY. AHEAD OF THE FRONT...LOW LEVEL JET WILL PEAK IN THE
60-70KT RANGE MONDAY EVENING POSING THE POTENTIAL FOR GUSTY
THUNDERSTORMS.
IN THE SYNOPTIC PICTURE...500MB HEIGHTS DROP BEHIND THE FRONT WITH
HIGH PRESSURE GRADUALLY MOVING IN. EXPECTING A MUCH COOLER DAY ON
TUESDAY...AND WILL NEED TO WATCH THE TEMPERATURES IN THE LONG TERM
TUESDAY NIGHT WITH THE GROWING SEASON GRADUALLY GET GOING. WILL KEEP
AN EYE ON THIS OVER THE NEXT FEW DAYS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
MODELS IN GENERAL AGREEMENT WITH COLD FRONT OVER THE AREA MONDAY
NIGHT...WITH LOW PRESSURE FORMING OVER THE SE STATES AND THEN
MOVING UP THE FRONT ON TUESDAY. THERE COULD BE SOME SCT THUNDER
WITH THE FRONT MONDAY NIGHT WITH SOME INSTABILITY...BUT NOT GREAT.
LOW QUICKLY MOVES UP FRONT AND CONTINUES HIGH POPS OVER THE AREA.
THEN MOVES OUT TUESDAY NIGHT. COLD HIGH PRESSURE QUICKLY MOVES IN
BEHIND THE SYSTEM AND THE HIGHEST ELEVATIONS COULD SEE A LITTLE
SNOW BEFORE SYSTEM EXITS.
COLD HIGH PRESSURE IS IN CONTROL FOR THE REST OF THE WEEK WITH A
GRADUAL WARMING TREND TOWARDS THE WEEKEND. WENT WITH A CONSENSUS
BLEND OF TEMPS THROUGHOUT.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
WARM FRONT...NOTICEABLE IN DEWPOINT FIELDS SLOWLY LIFTS NORTH
THROUGH THIS AFTERNOON. IN THE WARM SECTOR..SOUTH OF
THE BOUNDARY...A CU FIELD IS BUILDING AS SEEN ON VISIBLE SATELLITE
IMAGES. HIGH RESOLUTION MODELS SUGGEST ISOLATED TO SCATTERED
SHOWERS ARE POSSIBLE WITH WEAK DIURNAL HEATING CONVECTION. CODED A
BKN DECK AROUND 3500 FEET SOUTH OF THE BOUNDARY MAINLY AFFECTING
BKW. OVERALL...EXPECT VFR CONDITIONS WITH SOUTHERLY GUSTY WINDS
DUE TO DIFFERENTIAL HEATING BETWEEN THE CU FIELD AND VERY FEW AND
WEAK OUTFLOW BOUNDARIES OUT OF THE HEAVIER SHOWERS IF ANY.
EXPECT LOWER ATMOSPHERE TO DECOUPLE EARLY TONIGHT.
HOWEVER...MODELS INCREASE SOUTHWEST FLOW ALOFT. THESE WINDS WILL
PROBABLY MIX DOWN TO THE SURFACE MID MORNING SUNDAY. CODED THIS
FEATURE IN THE EXPECTED PART OF TAF. HIT AND MISS PCPN PRESENT LOW
CONFIDENCE TO INCLUDE SHOWERS IN TAF AT THIS POINT FOR THIS
AFTERNOON.
WITH WIND INCREASING ALOFT OVERNIGHT...EXPECT LESS FOG FORMATION
EXCEPT OVER SHELTERED RIVER VALLEYS IF THEY RECEIVE RAIN THIS
AFTERNOON. CONFIDENCE IS LOW PER LAV AND OTHER GUIDANCE.
THEREFORE...DID NOT INCLUDE IN TAF EITHER.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SUNDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: OCCURRENCE OF RIVER AND VALLEY FOG OVERNIGHT
COULD MATERIALIZE OVER AREAS THAT RECEIVE PCPN THIS AFTERNOON.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z SUNDAY...
IFR CONDITIONS EXPECTED LATE MONDAY INTO MONDAY NIGHT UNDER
MODERATE RAIN SHOWERS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...MZ/26
NEAR TERM...ARJ/JMV
SHORT TERM...26
LONG TERM...21
AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS TULSA OK
645 PM CDT SUN APR 13 2014
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
LINE OF THUNDER MOVING THROUGH THE AREA HAS ALREADY PASSED
TAF SITES KBVO KRVS KTUL. ONE TO TWO HOUR PERIOD OF THUNDER
AT SITES KXNA KFYV KMLC KFSM BETWEEN 00Z AND 04Z THIS EVENING.
MVFR CIGS TRAIL THUNDER/COLD FRONT BY ONE TO THREE HOURS.
MVFR CIGS AND SCATTERED SHOWERS MONDAY MORNING INTO AFTERNOON.
DIMINISHING CLOUD LATE IN PERIOD.
&&
.PREV DISCUSSION... /ISSUED 409 PM CDT SUN APR 13 2014/
DISCUSSION...
SQUALL LINE DEVELOPING ALONG THE COLD FRONT IS EXPECTED TO
CONTINUE TO BUILD SOUTH AND SWEEP ACROSS THE ENTIRE FORECAST AREA
LATE THIS AFTERNOON AND THIS EVENING AS SHOWN BY THE LATEST RUNS
OF THE HRRR AND LOCAL IN-HOUSE MODELS. THE MAIN SEVERE WEATHER
THREAT WILL LIKELY BE TRANSITIONING FROM HAIL TO DAMAGING WINDS
OVER TIME...WITH TORNADO PROBABILITIES BEING QUITE LOW DUE TO THE
LINEAR NATURE OF THE STORMS. INSTABILITY DECREASES WITH EASTWARD
EXTENT DIE TO PERSISTENT CLOUDS/SHOWERS IN SOUTHEAST OKLAHOMA AND
WESTERN ARKANSAS SO THERE IS ALSO SOME QUESTION AS TO WHETHER
STORMS WILL MAINTAIN THEIR INTENSITY INTO THIS EVENING.
MUCH COLDER AIR WILL OVERSPREAD THE AREA BEHIND THE FRONT. SOME
LIGHT RAIN WILL BE POSSIBLE MONDAY AHEAD OF A SECONDARY UPPER TROF
BUT AMOUNTS WILL BE VERY LIGHT. CLEARING SKIES AND LIGHT WINDS
WILL RESULT IN A FREEZE IN ALL AREAS TUESDAY MORNING AND HAVE NOW
PLACED THE ENTIRE FORECAST AREA UNDER A FREEZE WARNING. MOST
LOCATIONS WILL BE VERY NEAR THE COLDEST TEMPERATURES EVER RECORDED
FOR SO LATE IN THE SEASON...WHICH AT TUL/MLC/FYV/FSM ARE THE SAME
AS THE RECORD LOWS FOR THE DATE OF APRIL 15TH.
TEMPERATURES WILL WARM BACK CLOSER TO NORMAL FOR THE REST OF THE
WEEK INTO NEXT WEEKEND...WITH SHOWER AND THUNDERSTORM CHANCES
THURSDAY/THURSDAY NIGHT AND AGAIN SATURDAY NIGHT/SUNDAY.
STAYED CLOSE TO GUIDANCE TEMPERATURES THE NEXT COUPLE DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 38 47 28 61 / 10 30 0 0
FSM 46 50 28 61 / 70 30 10 0
MLC 41 48 29 61 / 60 20 10 0
BVO 36 47 25 61 / 10 30 0 0
FYV 39 43 24 57 / 90 30 10 0
BYV 40 43 25 56 / 70 40 10 0
MKO 40 47 27 60 / 90 30 10 0
MIO 37 44 26 59 / 70 40 10 0
F10 39 47 28 61 / 50 20 10 0
HHW 46 52 30 60 / 40 20 10 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...FREEZE WARNING FROM 1 AM TUESDAY TO 9 AM TUESDAY FOR OKZ049-
OKZ053-OKZ054-OKZ055-OKZ056-OKZ057-OKZ058-OKZ059-OKZ060-
OKZ061-OKZ062-OKZ063-OKZ064-OKZ065-OKZ066-OKZ067-OKZ068-
OKZ069-OKZ070-OKZ071-OKZ072-OKZ073-OKZ074-OKZ075-OKZ076.
AR...FREEZE WARNING FROM 1 AM TUESDAY TO 9 AM TUESDAY FOR ARZ001-
ARZ002-ARZ010-ARZ011-ARZ019-ARZ020-ARZ029.
&&
$$
SHORT TERM...18
LONG TERM....18
AVIATION...21
AREA FORECAST DISCUSSION
NWS NORMAN OK
128 PM CDT SAT APR 12 2014
.AVIATION...
GUSTY SOUTH WIND WILL CHANGE TO WEST AND NORTH ON SUNDAY. A
DRYLINE WILL BRING STRONG WEST WINDS SUNDAY MORNING INTO WEST
CENTRAL OKLAHOMA BEFORE A COLD FRONT MOVES QUICKLY SOUTHEAST
DURING THE DAY. SHOWERS AND THUNDERSTORMS ARE EXPECTED IN NORTH
CENTRAL AND PART OF CENTRAL OK SUNDAY AFTERNOON. MVFR CEILINGS ARE
EXPECTED TO FORM TONIGHT IN CENTAL AND SOUTHEAST OKLAHOMA.
&&
.PREV DISCUSSION... /ISSUED 1118 AM CDT SAT APR 12 2014/
UPDATE...
VERY DRY AIR HAS PUSHED INTO FAR NORTHWEST OKLAHOMA LATE
THIS MORNING BUT SURFACE WINDS ARE NOT TOO STRONG AT THE
MOMENT. LATER THIS AFTERNOON...VERY LOW HUMIDITY IS EXPECTED TO
PUSH FARTHER INTO WESTERN OKLAHOMA. RECENT RUNS OF THE HRRR BRING
VERY DRY AIR INTO THE WESTERN THIRD OF THE STATE AND THIS APPEARS
OVERDONE. CURRENT RED FLAG AREA APPEARS OK.
NAM12/GFS DO VERY LITTLE WITH REGARDS TO CONVECTION LATE THIS
AFTERNOON. PERHAPS A STORM OR TWO MAY ATTEMPT TO FORM.
A FIRE WEATHER WATCH WAS ISSUED FOR SOUTHWEST OKLAHOMA AND NORTH
TEXAS FOR SUNDAY...AS VERY DRY AND WINDY CONDITIONS ARE EXPECTED
AHEAD OF THE FRONT SUNDAY. MOST MODELS SUGGEST THE BEST AREA FOR
STORMS AND SEVERE WEATHER WILL BE ALONG AND EAST OF I-35 SUNDAY
AFTERNOON/EVENING.
MEANWHILE...GUSTY SOUTHERLY WINDS WILL PREVAIL UNTIL THE FRONT
MOVES THROUGH SUNDAY.
PREV DISCUSSION... /ISSUED 620 AM CDT SAT APR 12 2014/
AVIATION...
MVFR CIGS SPREADING THROUGH TX INTO SE OK THIS MORNING MAY
SPREAD INTO ERN TAF SITES EARLY THIS MORNING... BEFORE SCATTERING
OUT LATER TODAY. BRISK SOUTH WINDS WWILL PREVAIL THROUGH THE DAY
AREAWIDE. ISOLATED TSRA POSSIBLE WRN OK LATE AFTN...BUT PROB TOO LOW
TO INCLUDE IN ANY PARTICULAR TAF. MORE WIDESPREAD MVFR CIGS EXPECTED
TO DEVELOP LATE TONIGHT WITH CONTINUED MOIST SLY FLOW.
PREV DISCUSSION... /ISSUED 417 AM CDT SAT APR 12 2014/
DISCUSSION...
ACTIVE WEATHER PATTERN ACROSS THE REGION THE NEXT COUPLE OF DAYS.
SOUTHERLY WINDS WILL BE ON THE INCREASE TODAY IN RESPONSE TO
DEEPENING SURFACE LOW OVER WESTERN KS. DRYLINE EXPECTED TO PUSH
EASTWARD INTO FAR WESTERN AREAS THIS AFTERNOON. BRISK SOUTHWEST
WINDS...VERY WARM TEMPS...AND LOW RH BEHIND THE DRYLINE WILL LEAD
TO CRITICAL FIRE WEATHER CONDITIONS THERE BY LATE AFTERNOON AND
WILL GO AHEAD WITH A RED FLAG WARNING. WILL MAINTAIN LOW POPS FOR
THIS AFTERNOON AS STRONG HEATING AND CONVERGENCE ALONG THE DRYLINE
MIGHT BE ABLE TO OVERCOME THE CAP FOR AN ISOLATED STORM OR TWO.
COLD FRONT WILL BEGIN SURGING SOUTH SATURDAY NIGHT AS AMPLIFYING LONG
WAVE TROUGH APPROACHES FROM THE NW. FRONT WILL BE NEARING THE NW
CORNER OF THE FA BY SUNRISE SUNDAY. ABUNDANT LOW LEVEL MOISTURE
EXPECTED TO BE IN PLACE AHEAD OF FRONT ON SUNDAY. LEAD SRN BRANCH
S/W TROUGH EXPECTED TO EJECT NEWD ACROSS THE SOUTHERN PLAINS ON
SUNDAY AIDING IN THE DEVELOPMENT OF THUNDERSTORMS ALONG THE
ADVANCING FRONT AS WELL AS ALONG THE DRYLINE PUSHING EASTWARD
TOWARD CENTRAL OK. INSTABILITY AND SHEAR WILL BE FAVORABLE FOR
SEVERE STORM DEVELOPMENT...ESP IN EASTERN AREAS BY SUNDAY
AFTERNOON.
MUCH COLDER AIR WILL SWEEP THROUGH THE SOUTHERN PLAINS IN THE WAKE
OF THE FRONT SUNDAY AFTERNOON AND NIGHT. THE MAIN AREA OF
SHOWERS/TSTMS FOCUSED IN THE VICINITY OF THE FRONT WILL MOVE
SOUTHEAST OF THE AREA SUNDAY NIGHT. LIGHT PRECIP ASSOCIATED WITH
THE MAIN UPPER TROUGH WILL LIKELY SPREAD BACK INTO NWRN OK LATE
SUNDAY NIGHT. TEMP PROFILES LOOK COLD ENOUGH FOR POSSIBILITY OF
OF RAIN/SNOW IN THE NORTHWEST LATE SUNDAY NIGHT INTO MONDAY
MORNING ALTHOUGH DO NOT EXPECT MUCH IN THE WAY OF SNOW
ACCUMULATION. PRECIP EXPECTED TO END BY MONDAY AFTERNOON AS UPPER
TROUGH MOVES THROUGH. COLD NIGHT IN STORE MONDAY NIGHT WITH
FREEZE/FROST ANTICIPATED OVER MUCH OF THE FA.
DRY WEATHER WITH WARMER TEMPS EXPECTED THROUGH MID TO LATE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 65 83 39 48 / 10 50 40 30
HOBART OK 65 83 38 52 / 20 20 10 20
WICHITA FALLS TX 67 89 40 53 / 10 20 20 10
GAGE OK 58 72 34 49 / 20 20 40 30
PONCA CITY OK 65 75 35 47 / 10 70 40 40
DURANT OK 65 76 44 52 / 10 50 60 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...FREEZE WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY MORNING FOR
OKZ004>032-034-035-038>043-046>048.
RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR OKZ004-005-
009>011-014-015-021-033-034-036.
FIRE WEATHER WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING
FOR OKZ021>023-033>038-044.
TX...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR TXZ083-084-087.
FIRE WEATHER WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING
FOR TXZ083>089.
&&
$$
06/09/09
AREA FORECAST DISCUSSION
NWS NORMAN OK
1118 AM CDT SAT APR 12 2014
.UPDATE...
VERY DRY AIR HAS PUSHED INTO FAR NORTHWEST OKLAHOMA LATE
THIS MORNING BUT SURFACE WINDS ARE NOT TOO STRONG AT THE
MOMENT. LATER THIS AFTERNOON...VERY LOW HUMIDITY IS EXPECTED TO
PUSH FARTHER INTO WESTERN OKLAHOMA. RECENT RUNS OF THE HRRR BRING
VERY DRY AIR INTO THE WESTERN THIRD OF THE STATE AND THIS APPEARS
OVERDONE. CURRENT RED FLAG AREA APPEARS OK.
NAM12/GFS DO VERY LITTLE WITH REGARDS TO CONVECTION LATE THIS
AFTERNOON. PERHAPS A STORM OR TWO MAY ATTEMPT TO FORM.
A FIRE WEATHER WATCH WAS ISSUED FOR SOUTHWEST OKLAHOMA AND NORTH
TEXAS FOR SUNDAY...AS VERY DRY AND WINDY CONDITIONS ARE EXPECTED
AHEAD OF THE FRONT SUNDAY. MOST MODELS SUGGEST THE BEST AREA FOR
STORMS AND SEVERE WEATHER WILL BE ALONG AND EAST OF I-35 SUNDAY
AFTERNOON/EVENING.
MEANWHILE...GUSTY SOUTHERLY WINDS WILL PREVAIL UNTIL THE FRONT
MOVES THROUGH SUNDAY.
&&
.PREV DISCUSSION... /ISSUED 620 AM CDT SAT APR 12 2014/
AVIATION...
MVFR CIGS SPREADING THROUGH TX INTO SE OK THIS MORNING MAY
SPREAD INTO ERN TAF SITES EARLY THIS MORNING... BEFORE SCATTERING
OUT LATER TODAY. BRISK SOUTH WINDS WWILL PREVAIL THROUGH THE DAY
AREAWIDE. ISOLATED TSRA POSSIBLE WRN OK LATE AFTN...BUT PROB TOO LOW
TO INCLUDE IN ANY PARTICULAR TAF. MORE WIDESPREAD MVFR CIGS EXPECTED
TO DEVELOP LATE TONIGHT WITH CONTINUED MOIST SLY FLOW.
PREV DISCUSSION... /ISSUED 417 AM CDT SAT APR 12 2014/
DISCUSSION...
ACTIVE WEATHER PATTERN ACROSS THE REGION THE NEXT COUPLE OF DAYS.
SOUTHERLY WINDS WILL BE ON THE INCREASE TODAY IN RESPONSE TO
DEEPENING SURFACE LOW OVER WESTERN KS. DRYLINE EXPECTED TO PUSH
EASTWARD INTO FAR WESTERN AREAS THIS AFTERNOON. BRISK SOUTHWEST
WINDS...VERY WARM TEMPS...AND LOW RH BEHIND THE DRYLINE WILL LEAD
TO CRITICAL FIRE WEATHER CONDITIONS THERE BY LATE AFTERNOON AND
WILL GO AHEAD WITH A RED FLAG WARNING. WILL MAINTAIN LOW POPS FOR
THIS AFTERNOON AS STRONG HEATING AND CONVERGENCE ALONG THE DRYLINE
MIGHT BE ABLE TO OVERCOME THE CAP FOR AN ISOLATED STORM OR TWO.
COLD FRONT WILL BEGIN SURGING SOUTH SATURDAY NIGHT AS AMPLIFYING LONG
WAVE TROUGH APPROACHES FROM THE NW. FRONT WILL BE NEARING THE NW
CORNER OF THE FA BY SUNRISE SUNDAY. ABUNDANT LOW LEVEL MOISTURE
EXPECTED TO BE IN PLACE AHEAD OF FRONT ON SUNDAY. LEAD SRN BRANCH
S/W TROUGH EXPECTED TO EJECT NEWD ACROSS THE SOUTHERN PLAINS ON
SUNDAY AIDING IN THE DEVELOPMENT OF THUNDERSTORMS ALONG THE
ADVANCING FRONT AS WELL AS ALONG THE DRYLINE PUSHING EASTWARD
TOWARD CENTRAL OK. INSTABILITY AND SHEAR WILL BE FAVORABLE FOR
SEVERE STORM DEVELOPMENT...ESP IN EASTERN AREAS BY SUNDAY
AFTERNOON.
MUCH COLDER AIR WILL SWEEP THROUGH THE SOUTHERN PLAINS IN THE WAKE
OF THE FRONT SUNDAY AFTERNOON AND NIGHT. THE MAIN AREA OF
SHOWERS/TSTMS FOCUSED IN THE VICINITY OF THE FRONT WILL MOVE
SOUTHEAST OF THE AREA SUNDAY NIGHT. LIGHT PRECIP ASSOCIATED WITH
THE MAIN UPPER TROUGH WILL LIKELY SPREAD BACK INTO NWRN OK LATE
SUNDAY NIGHT. TEMP PROFILES LOOK COLD ENOUGH FOR POSSIBILITY OF
OF RAIN/SNOW IN THE NORTHWEST LATE SUNDAY NIGHT INTO MONDAY
MORNING ALTHOUGH DO NOT EXPECT MUCH IN THE WAY OF SNOW
ACCUMULATION. PRECIP EXPECTED TO END BY MONDAY AFTERNOON AS UPPER
TROUGH MOVES THROUGH. COLD NIGHT IN STORE MONDAY NIGHT WITH
FREEZE/FROST ANTICIPATED OVER MUCH OF THE FA.
DRY WEATHER WITH WARMER TEMPS EXPECTED THROUGH MID TO LATE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 84 65 83 39 / 10 10 50 40
HOBART OK 87 65 83 38 / 20 20 20 10
WICHITA FALLS TX 88 67 89 40 / 10 10 20 20
GAGE OK 91 58 72 34 / 20 20 20 40
PONCA CITY OK 85 65 75 35 / 10 10 70 40
DURANT OK 79 65 76 44 / 10 10 50 60
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR OKZ004-005-
009>011-014-015-021-033-034-036.
FIRE WEATHER WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING
FOR OKZ021>023-033>038-044.
TX...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR TXZ083-084-087.
FIRE WEATHER WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING
FOR TXZ083>089.
&&
$$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
805 PM CDT SUN APR 13 2014
.UPDATE...
500 MB JET STREAK IS BEGINNING TO ENTER THE MS RIVER VALLEY WHICH
IS LARGELY FUELING THE AREA OF SHOWERS AND THUNDERSTORMS IN THAT
REGION. THIS WILL CONTINUE TO PROGRESS EASTWARD OVER THE NEXT FEW
HOURS. MID LEVEL DRY AIR...AS SHOWN IN THE RUC TIME HEIGHT AND THE
00Z ROAB...SHOULD KEEP THE SHOWERS FROM ENTERING THE MID STATE BEFORE
06Z. THEREFORE...OPTED TO REMOVE POP CHANCES PRIOR TO 03Z AND ONLY
LEFT WESTERN AREAS IN SLGT CHC CATEGORY UNTIL 06Z. ALL SHORT RANGE
MODELS KEEP ANY QPF WEST OF THE TN RIVER UNTIL THAT POINT. POP
CHANCES RISE AFTER 06Z.
AS FOR TONIGHTS STORM SEVERITY POTENTIAL...CONVECTIVELY...THE
PARAMETERS ARE NOT IMPRESSIVE WITH CIN OVERCOMING CAPE ON THE RUC
FORECAST SOUNDINGS SHORTLY AFTER MIDNIGHT. HOWEVER...DYNAMICALLY
SPEAKING...A STOUT 850 MB LLJ AND 500 MB JET MAX SHOULD KEEP
THUNDER PLENTIFUL. GUSTY WIND POTENTIAL WILL BE STILL BE MODERATE
WITH THE INITIAL STORMS BETWEEN 03Z AND 09Z IN THE WEST DUE TO MID
LEVEL DRY AIR AND INVERTED V SOUNDINGS OUT WEST. PLUS...SHEAR
VALUES WOULD HINT AT THE POSSIBILITY OF SOME BOWING SEGMENTS WITH
THE MORE INTENSE STORMS WITHIN THE LINE. HOWEVER WIND POTENTIAL
SHOULD DROP OFF SUBSTANTIALLY SOON AFTER STORM ONSET AS THE LOW LEVEL
ATMOSPHERE MOISTENS WITH THE HEALTHY QPF WE SHOULD RECEIVE.
&&
.PREV DISCUSSION... /ISSUED 656 PM CDT SUN APR 13 2014/
UPDATE...FOR 00Z AVIATION FORECAST
AVIATION...
EXTENSIVE HIGH CLOUDS AND GUSTY WINDS WILL CONTINUE ACROSS MID TN
THIS EVENING AS UPPER DISTURBANCE MOVES TOWARD MS VALLEY. CIGS
WILL BEGIN TO LOWER AND RAIN CHANCES WILL GO UP AS MOISTURE
CONTINUES TO INCEASE LATER TONIGHT INTO MONDAY. BEST CHANCES FOR
SHOWERS AND ISOLATED TSTMS SHOULD BE IN A 2 TO 4 HOUR WINDOW THAT
STARTS AT 08Z AT KCKV...AT 09Z AT KBNA AND AFTER 12Z AT KCSV.
CONTINUED CHANCES FOR SHOWERS AND ISOLATED TSTMS MONDAY AFTERNOON
AS COLD FRONT MOVES SLOWLY INTO THE REGION. FRONT COULD MAKE IT
TO KCKV CLOSE TO 00Z TUE...BUT NOT UNTIL AFTER 00Z TUE AT
KBNA/KCSV.
PREV DISCUSSION... /ISSUED 222 PM CDT SUN APR 13 2014/
DISCUSSION...
CLOUDS WILL INCREASE THROUGH THE AFTERNOON AS SURFACE RIDGE BEGINS
TO WEAKEN OVER THE SOUTHEAST AS CENTRAL AND SOUTHERN PLAINS LOW
CONTINUES TO DEEPEN. GRADIENT BETWEEN THE TWO SYSTEMS IS TIGHT
ENOUGH TO KEEP WINDS UP TONIGHT AND DURING THE DAY ON MONDAY.
SHOWERS AND A FEW THUNDERSTORMS WILL WORK INTO FAR WESTERN MIDDLE
TENNESSEE AROUND MIDNIGHT AND TRANSLATE EASTWARD OVERNIGHT. MODELS IN
AGREEMENT IN COLD FRONT ALONG THE MISSISSIPPI RIVER BY 12Z MONDAY
WITH SHOWERS AND STORMS ACROSS THE MID STATE. A FEW STORMS COULD
BE STRONG TO MARGINIALLY SEVERE DURING THE DAY MONDAY. SURFACE WINDS
WILL BE GUSTY. FROPA AT CLARKSVILLE MONDAY AROUND 18Z...AND
AROUND 23Z AT NASHVILLE AND TOWARDS MIDNIGHT MONDAY NIGHT ALONG
THE PLATEAU. WINDS PICK UP IN SPEED OUT OF THE NORTHWEST AND GUSTY
MONDAY NIGHT...COULD SEE GUSTS TO 30 TO 35 MPH. SHARPLY COLDER
MONDAY NIGHT WITH LOWS DOWN IN THE MID AND UPPER 30S BUT NO FROST
DUE TO WIND AND CLOUDS. BLUSTERY DAY ON TUESDAY WITH HIGHS MOSTLY
IN THE UPPER 40S. (THE LOWEST DAILY HIGH AT NASHVILLE FOR APRIL
15TH (TUESDAY) IS 46 DEGREES SET BACK IN 1903). FREEZE LIKELY
TUESDAY NIGHT WITH LOWS RANGING FROM 28-32 DEGREES. HIGHS
WEDNESDAY THROUGH FRIDAY IN THE 60S WITH DRY WEATHER UNTIL FRIDAY
WHEN ANOTHER FRONTAL SYSTEM APPROACHES FROM THE WEST BRINGING A
CHANCE FOR SHOWERS AND A FEW THUNDERSTORMS. PLEASANT WEATHER OVER
THE WEEKEND WITH HIGHS AROUND 70.
CLIMATE...FREEZE LOOKS LIKELY TUESDAY NIGHT/WEDNESDAY MORNING
WITH LOWS RANGING FROM 28 TO 32 DEGREES. SENSITIVE PLANTS WILL
NEED TO BE PROTECTED. THE RECORD LOW AT NASHVILLE FOR APRIL 16TH
IS 28 DEGREES SET BACK IN 1988.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
TB12
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
618 PM CDT SUN APR 13 2014
.UPDATE...
UPDATED FOR WIND ADVISORY CANCELLATION.
&&
.DISCUSSION...
GUSTY SOUTH WINDS HAVE TAPERED OFF ALONG AND EAST OF THE
MISSISSIPPI RIVER TO BELOW ADVISORY CRITERIA OVER THE PAST TWO
HOURS. THIS IS LIKELY DUE TO THE INCREASE CONVECTIVE ACTIVITY
TAKING PLACE. WINDS WILL REMAIN IN THE 15 TO 20 MPH SUSTAINED RANGE
WITH OCCASIONAL GUSTS UP TO 30 MPH OVERNIGHT OUTSIDE OF THE
EXPECTED SHOWERS AND STORMS.
JAB
&&
.PREV DISCUSSION... /ISSUED 415 PM CDT SUN APR 13 2014/
DISCUSSION...
SYNOPSIS...
A COUPLE OF UPPER LEVEL SHORTWAVES WILL MOVE THROUGH THE MID-SOUTH
THIS EVENING AS A STRONG LOW PRESSURE SYSTEM DEPARTS TO THE
NORTHEAST. AS THE LOW MOVES OFF TO THE NORTHEAST...WINDS WILL
BECOME MORE BACKED AT THE SURFACE AND A STRONG 50 TO 60 KT MID-
LEVEL WESTERLY JET WILL SUPPORT THE CHANCE FOR SOME STRONG TO
SEVERE THUNDERSTORMS THROUGH LATE THIS EVENING...MAINLY ALONG AND WEST
OF THE MISSISSIPPI RIVER. THE PRIMARY HAZARDS WILL BE DAMAGING
WINDS AND LARGE HAIL AS THE PRIMARY MODE IS EXPECTED TO BE A
FORCED LINE OF STORMS...ALTHOUGH A TORNADO CANNOT BE RULED OUT.
OVERNIGHT TONIGHT AND INTO TOMORROW AFTERNOON...
SUFFICIENT INSTABILITY TO SUPPORT SEVERE THUNDERSTORM DEVELOPMENT WILL
BE AVAILABLE OVER A LARGE PART OF THE FORECAST AREA OVERNIGHT AND
INTO TOMORROW AFTERNOON...WITH THE BEST INGREDIENTS FOR SEVERE
WEATHER SPECIFICALLY OVER NORTH MISSISSIPPI DURING LATE MORNING TO
AFTERNOON HOURS ON MONDAY. MODEL GUIDANCE SUGGESTS THAT 1000 TO
NEAR 2000 J/KG OF SBCAPE WILL BE ON HAND...ALONG WITH LI/S -6 TO
-8C...AND 0-6 KM BULK SHEAR AROUND 60KTS. IN ADDITION...MODELS ARE
IN AGREEMENT THAT A DEVELOPING SURFACE LOW WILL TRACK ALONG THE
COLD FRONT AND MOVE TO THE NORTHEAST BY TOMORROW EVENING. ALL OF
THESE PARAMETERS AND THE LOCATION OF LOW WILL SUPPORT A POTENTIAL
FOR DAMAGING WINDS...HAIL...AND PERHAPS A TORNADO. THE LIMITING
FACTOR WILL OBVIOUSLY BE CLOUD COVER TOMORROW IN THE WARM
SECTOR...AND UNIDIRECTIONAL WIND PROFILES. THE COLD FRONT WILL
EXIT THE REGION BY LATE MONDAY NIGHT.
BEHIND THE FRONT...VERY COLD AND DRY AIR WILL FUNNEL INTO THE REGION
BY TUESDAY MORNING. CURRENT THINKING IS THAT TEMPERATURES WILL
DIP INTO THE 30S...BUT THE ATMOSPHERE SHOULD REMAIN MOIST ENOUGH
TO FEND OFF ANY FROST FORMING OVERNIGHT ON TUESDAY. FOG WILL MOST LIKELY
BE WHAT DEVELOPS INSTEAD.
BY TUESDAY...TEMPERATURES WILL STRUGGLE TO CLIMB INTO THE UPPER 50S
DURING THE DAY AS STRONG CAA WILL BE PERSISTENT ALL DAY LONG.
WINDS WILL DIE DOWN AFTER MIDNIGHT AND TEMPERATURES ARE EXPECTED
TO DROP OFF VERY QUICKLY. LOWS WILL BOTTOM OUT IN THE LOWER 30S
AND MANY PLACES WILL DIP INTO THE UPPER 20S. A FREEZE WARNING
WILL MOST LIKELY BE NEEDED FOR WEDNESDAY MORNING.
BY WEDNESDAY HIGH PRESSURE WILL BUILD INTO THE REGION AND
TEMPERATURES WILL FINALLY BEGIN TO MODERATE AND A WARMING TREND
WILL BEGIN.
ANOTHER COLD FRONT IS EXPECTED TO MOVE THROUGH THE MID-SOUTH ON
FRIDAY INTO SATURDAY BRINGING RAIN A SLIGHT CHANCE OF
THUNDERSTORMS TO THE MID-SOUTH.
THIS WEEKEND...
HIGH PRESSURE WILL BRIEFLY BUILD IN ON SATURDAY BEFORE
ANOTHER SYSTEM MOVES IN BY LATE SUNDAY. SLIGHT CHANCES FOR RAIN
WILL BE POSSIBLE. BY MONDAY...TEMPERATURES ARE EXPECTED TO REBOUND
BACK TO SEASONAL TEMPERATURES WITH HIGHS IN THE 70S AND LOWS IN
THE 50S.
AC3
&&
.AVIATION...
18Z TAFS
MAIN CONCERN REMAINS TIMING OF TSRA ARRIVAL THIS EVENING. FOR THE
18Z TAFS... HAVE MADE ONLY MINOR TIMING ADJUSTMENTS BASED ON 12Z
NAM AND 15Z HRRR MODELS. TS CANNOT BE RULED OUT FOR ANY PERIOD
BEYOND 03Z...WITH MULTIPLE UPPER LEVEL IMPULSES LIFTING THROUGH
AHEAD OF THE MAIN UPPER TROF. HAVE LIMITED TS/VCTS MENTION TO
THOSE PERIODS MOST FAVORABLE. SUSPECT THAT THERE WILL BE LULL
DURING THE 11Z TO 15Z PERIOD...BUT WITH IFR/MVFR CIGS PREVAILING
WITH SCATTERED SHRA.
PWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MIDLAND/ODESSA TX
1242 PM CDT Sat Apr 12 2014
.DISCUSSION...
Please see the 18z aviation forecast below.
&&
.AVIATION...
Intensifying surface low pressure over western Kansas and the
Oklahoma Panhandle will result in breezy to windy southwest flow
at TAF sites over southeast New Mexico and southwest Texas. Upper
level disturbances moving into the area from Mexico will continue
to provided associated high cloudiness. VFR conditions will
persist through the period.
&&
.PREV DISCUSSION... /ISSUED 442 AM CDT Sat Apr 12 2014/
DISCUSSION...
More warm and dry weather today, with a canopy of high clouds still
parading across the area ahead of Sunday`s system (currently
located over California). Critical fire weather concerns continue
primarily across Southeast New Mexico and its bordering Texas
counties today, with potentially widespread critical conditions on
Sunday. For more information, please see the fire weather
discussion below. Similar to yesterday, afternoon high
temperatures today will top out in the upper 80s and low 90s for
most of the area. A sharpening lee surface trough this afternoon
will allow the dry line to mix to the eastern edges of the CWA,
roughly along a Snyder-Big Lake-Sanderson line. While convective
development is possible along and east of the dry line (where
better moisture resides), the cap remains strong with around
100-200 j/kg CIN and have kept thunderstorms out of the forecast
for these areas.
Models are also attempting to develop showers and thunderstorms
this afternoon over the higher terrain of Mexico as a subtle
shortwave trough traverses Chihuahua. The NAM, GFS, and RUC all
develop QPF this afternoon and evening from Culberson County into
the Marfa Plateau as a result of this activity moving northeast.
Forecast soundings do indicate top down moistening across
southwest Texas, but still maintain rather large surface
temperature-dew point spreads (30-40 degrees). If anything
actually does make it into Texas (and confidence is not high that
it will), a very dry sub cloud layer makes virga with localized
gusty winds and occasional lightning seem the more likely outcome.
The more noticeable effect of the sharpening surface trough will be
an increase in surface winds today, with gusty southwest winds 15-25
MPH across lower elevations and higher speeds across higher terrain.
Expect windy conditions again Sunday as a shortwave trough crosses
the region, with height falls across the area producing slightly
cooler temperatures. As this trough swings across the area, it will send a
rather potent cold front through the area Sunday night. Expect the
front to push through the entire area by midday Monday.
A very tight pressure gradient (5 mb/50 miles) associated with
this front will produce possible wind advisory criteria (winds
25-35 MPH) behind the front mainly north of I-20. Given a
favorable northeast direction with these winds, a high wind
warning may also be needed for the Guadalupe Mountains (including
Guadalupe Pass). Blowing dust will be a concern with the winds
along and behind the front. Strongest winds look to materialize
between 10Z and 18Z on Monday morning. A secondary wave will dive south
Monday afternoon and, despite sufficient lift, the air over the
forecast area looks too moisture starved (PWATs around 0.3 in over
the northern Permian Basin) to support any of the precip models
are generating over the northern portions of the forecast area.
Temperatures will also be much colder behind Sunday`s front with the
potential for a late season freeze on Tuesday morning in the
mountains and northern Permian Basin. Areas along and north of I-20
will need to continue to monitor the forecast for issuance of any
freeze watches or warnings. Shortwave ridging builds across Texas
and New Mexico by mid-week, allowing temperatures to warm back to
near seasonal normals. The ECMWF and GFS are indicating a more
active pattern again heading into next weekend, but this far out
have different solutions. Kept the forecast dry into next weekend.
FIRE WEATHER...
Expecting another day of very dry air over much of the region with
minimum RH below 15 percent west of a dryline. As a surface low
moves over the Panhandle today should reach or exceed 20ft winds of
20 mph across SE NM... Guadalupe Mtns... Van Horn region... portions
of the Upper Trans Pecos and NW Permian Basin. Will update the Red
Flag Warning to include all of these locations. A few thunderstorms
possible this afternoon/evening across the Marfa Plateau... these
could be dry storms. Very dry air will spread across all of the
region Sunday as a west wind sweeps across the area. Minimum RH 10
percent or less. As the pressure gradient tightens 20ft winds will
exceed 20 mph over much of the area. Will continue the Fire Weather
Watch Sunday for all of W TX and SE NM. A strong cold front will
blow through the area Sunday night ending fire weather concerns for
a few days.
&&
.MAF WATCHES/WARNINGS/ADVISORIES...
NM...FIRE WEATHER WATCH from Sunday morning through Sunday evening
FOR THE FOLLOWING ZONES... Guadalupe Mountains NP/Lincoln
NF/LNZ...Southeast Plains/BLM Roswell/LNZ.
RED FLAG WARNING until 9 PM MDT this evening FOR THE FOLLOWING
ZONES... Guadalupe Mountains NP/Lincoln NF/LNZ...Southeast
Plains/BLM Roswell/LNZ.
TX...FIRE WEATHER WATCH from Sunday morning through Sunday evening
FOR THE FOLLOWING ZONES... Andrews...Big Bend Area...
Borden...Crane...Davis/Apache Mountains Area...Dawson...
Ector...Gaines...Glasscock...Guadalupe Mountains...Howard...
Loving...Marfa Plateau...Martin...Midland...Mitchell...
Pecos...Presidio Valley...Reagan...Reeves County and Upper
Trans Pecos...Scurry...Terrell...Upton...Van Horn and
Highway 54 Corridor...Ward...Winkler.
RED FLAG WARNING until 10 PM CDT /9 PM MDT/ this evening FOR THE
FOLLOWING ZONES... Dawson...Gaines...Guadalupe Mountains...
Reeves County and Upper Trans Pecos...Van Horn and Highway
54 Corridor.
&&
$$
03
AREA FORECAST DISCUSSION
NWS MIDLAND/ODESSA TX
631 AM CDT Sat Apr 12 2014
.DISCUSSION...
&&
.AVIATION...
VFR with extensive upper cloud deck today. SW wind today will
become gusty as surface trough deepens and winds aloft mix down.
Wind should stay up tonight.
&&
.PREV DISCUSSION... /ISSUED 442 AM CDT Sat Apr 12 2014/
DISCUSSION...
More warm and dry weather today, with a canopy of high clouds still
parading across the area ahead of Sunday`s system (currently
located over California). Critical fire weather concerns continue
primarily across Southeast New Mexico and its bordering Texas
counties today, with potentially widespread critical conditions on
Sunday. For more information, please see the fire weather
discussion below. Similar to yesterday, afternoon high
temperatures today will top out in the upper 80s and low 90s for
most of the area. A sharpening lee surface trough this afternoon
will allow the dry line to mix to the eastern edges of the CWA,
roughly along a Snyder-Big Lake-Sanderson line. While convective
development is possible along and east of the dry line (where
better moisture resides), the cap remains strong with around
100-200 j/kg CIN and have kept thunderstorms out of the forecast
for these areas.
Models are also attempting to develop showers and thunderstorms
this afternoon over the higher terrain of Mexico as a subtle
shortwave trough traverses Chihuahua. The NAM, GFS, and RUC all
develop QPF this afternoon and evening from Culberson County into
the Marfa Plateau as a result of this activity moving northeast.
Forecast soundings do indicate top down moistening across
southwest Texas, but still maintain rather large surface
temperature-dew point spreads (30-40 degrees). If anything
actually does make it into Texas (and confidence is not high that
it will), a very dry sub cloud layer makes virga with localized
gusty winds and occasional lightning seem the more likely outcome.
The more noticeable effect of the sharpening surface trough will be
an increase in surface winds today, with gusty southwest winds 15-25
MPH across lower elevations and higher speeds across higher terrain.
Expect windy conditions again Sunday as a shortwave trough crosses
the region, with height falls across the area producing slightly
cooler temperatures. As this trough swings across the area, it will send a
rather potent cold front through the area Sunday night. Expect the
front to push through the entire area by midday Monday.
A very tight pressure gradient (5 mb/50 miles) associated with
this front will produce possible wind advisory criteria (winds
25-35 MPH) behind the front mainly north of I-20. Given a
favorable northeast direction with these winds, a high wind
warning may also be needed for the Guadalupe Mountains (including
Guadalupe Pass). Blowing dust will be a concern with the winds
along and behind the front. Strongest winds look to materialize
between 10Z and 18Z on Monday morning. A secondary wave will dive south
Monday afternoon and, despite sufficient lift, the air over the
forecast area looks too moisture starved (PWATs around 0.3 in over
the northern Permian Basin) to support any of the precip models
are generating over the northern portions of the forecast area.
Temperatures will also be much colder behind Sunday`s front with the
potential for a late season freeze on Tuesday morning in the
mountains and northern Permian Basin. Areas along and north of I-20
will need to continue to monitor the forecast for issuance of any
freeze watches or warnings. Shortwave ridging builds across Texas
and New Mexico by mid-week, allowing temperatures to warm back to
near seasonal normals. The ECMWF and GFS are indicating a more
active pattern again heading into next weekend, but this far out
have different solutions. Kept the forecast dry into next weekend.
FIRE WEATHER...
Expecting another day of very dry air over much of the region with
minimum RH below 15 percent west of a dryline. As a surface low
moves over the Panhandle today should reach or exceed 20ft winds of
20 mph across SE NM... Guadalupe Mtns... Van Horn region... portions
of the Upper Trans Pecos and NW Permian Basin. Will update the Red
Flag Warning to include all of these locations. A few thunderstorms
possible this afternoon/evening across the Marfa Plateau... these
could be dry storms. Very dry air will spread across all of the
region Sunday as a west wind sweeps across the area. Minimum RH 10
percent or less. As the pressure gradient tightens 20ft winds will
exceed 20 mph over much of the area. Will continue the Fire Weather
Watch Sunday for all of W TX and SE NM. A strong cold front will
blow through the area Sunday night ending fire weather concerns for
a few days.
&&
.MAF WATCHES/WARNINGS/ADVISORIES...
NM...FIRE WEATHER WATCH from Sunday morning through Sunday evening
FOR THE FOLLOWING ZONES... Guadalupe Mountains NP/Lincoln
NF/LNZ...Southeast Plains/BLM Roswell/LNZ.
RED FLAG WARNING from 11 AM this morning to 9 PM MDT this
evening FOR THE FOLLOWING ZONES... Guadalupe Mountains
NP/Lincoln NF/LNZ...Southeast Plains/BLM Roswell/LNZ.
TX...FIRE WEATHER WATCH from Sunday morning through Sunday evening
FOR THE FOLLOWING ZONES... Andrews...Big Bend Area...
Borden...Crane...Davis/Apache Mountains Area...Dawson...
Ector...Gaines...Glasscock...Guadalupe Mountains...Howard...
Loving...Marfa Plateau...Martin...Midland...Mitchell...
Pecos...Presidio Valley...Reagan...Reeves County and Upper
Trans Pecos...Scurry...Terrell...Upton...Van Horn and
Highway 54 Corridor...Ward...Winkler.
RED FLAG WARNING from Noon CDT /11 AM MDT/ today to 10 PM CDT /9
PM MDT/ this evening FOR THE FOLLOWING ZONES... Dawson...
Gaines...Guadalupe Mountains...Reeves County and Upper
Trans Pecos...Van Horn and Highway 54 Corridor.
&&
$$
AREA FORECAST DISCUSSION
NWS MIDLAND/ODESSA TX
442 AM CDT Sat Apr 12 2014
.DISCUSSION...
More warm and dry weather today, with a canopy of high clouds still
parading across the area ahead of Sunday`s system (currently
located over California). Critical fire weather concerns continue
primarily across Southeast New Mexico and its bordering Texas
counties today, with potentially widespread critical conditions on
Sunday. For more information, please see the fire weather
discussion below. Similar to yesterday, afternoon high
temperatures today will top out in the upper 80s and low 90s for
most of the area. A sharpening lee surface trough this afternoon
will allow the dry line to mix to the eastern edges of the CWA,
roughly along a Snyder-Big Lake-Sanderson line. While convective
development is possible along and east of the dry line (where
better moisture resides), the cap remains strong with around
100-200 j/kg CIN and have kept thunderstorms out of the forecast
for these areas.
Models are also attempting to develop showers and thunderstorms
this afternoon over the higher terrain of Mexico as a subtle
shortwave trough traverses Chihuahua. The NAM, GFS, and RUC all
develop QPF this afternoon and evening from Culberson County into
the Marfa Plateau as a result of this activity moving northeast.
Forecast soundings do indicate top down moistening across
southwest Texas, but still maintain rather large surface
temperature-dew point spreads (30-40 degrees). If anything
actually does make it into Texas (and confidence is not high that
it will), a very dry sub cloud layer makes virga with localized
gusty winds and occasional lightning seem the more likely outcome.
The more noticeable effect of the sharpening surface trough will be
an increase in surface winds today, with gusty southwest winds 15-25
MPH across lower elevations and higher speeds across higher terrain.
Expect windy conditions again Sunday as a shortwave trough crosses
the region, with height falls across the area producing slightly
cooler temperatures. As this trough swings across the area, it will send a
rather potent cold front through the area Sunday night. Expect the
front to push through the entire area by midday Monday.
A very tight pressure gradient (5 mb/50 miles) associated with
this front will produce possible wind advisory criteria (winds
25-35 MPH) behind the front mainly north of I-20. Given a
favorable northeast direction with these winds, a high wind
warning may also be needed for the Guadalupe Mountains (including
Guadalupe Pass). Blowing dust will be a concern with the winds
along and behind the front. Strongest winds look to materialize
between 10Z and 18Z on Monday morning. A secondary wave will dive south
Monday afternoon and, despite sufficient lift, the air over the
forecast area looks too moisture starved (PWATs around 0.3 in over
the northern Permian Basin) to support any of the precip models
are generating over the northern portions of the forecast area.
Temperatures will also be much colder behind Sunday`s front with the
potential for a late season freeze on Tuesday morning in the
mountains and northern Permian Basin. Areas along and north of I-20
will need to continue to monitor the forecast for issuance of any
freeze watches or warnings. Shortwave ridging builds across Texas
and New Mexico by mid-week, allowing temperatures to warm back to
near seasonal normals. The ECMWF and GFS are indicating a more
active pattern again heading into next weekend, but this far out
have different solutions. Kept the forecast dry into next weekend.
&&
.FIRE WEATHER...
Expecting another day of very dry air over much of the region with
minimum RH below 15 percent west of a dryline. As a surface low
moves over the Panhandle today should reach or exceed 20ft winds of
20 mph across SE NM... Guadalupe Mtns... Van Horn region... portions
of the Upper Trans Pecos and NW Permian Basin. Will update the Red
Flag Warning to include all of these locations. A few thunderstorms
possible this afternoon/evening across the Marfa Plateau... these
could be dry storms. Very dry air will spread across all of the
region Sunday as a west wind sweeps across the area. Minimum RH 10
percent or less. As the pressure gradient tightens 20ft winds will
exceed 20 mph over much of the area. Will continue the Fire Weather
Watch Sunday for all of W TX and SE NM. A strong cold front will
blow through the area Sunday night ending fire weather concerns for
a few days.
&&
.PRELIMINARY POINT TEMPS/POPS...
ANDREWS TX 89 60 84 41 / 10 10 0 10
BIG SPRING TX 91 65 86 41 / 10 10 10 0
CARLSBAD NM 89 58 85 47 / 10 10 0 0
DRYDEN TX 92 66 95 55 / 10 10 10 0
FORT STOCKTON TX 90 63 88 45 / 10 10 0 0
GUADALUPE PASS TX 77 55 75 36 / 10 10 0 10
HOBBS NM 87 54 82 39 / 10 10 0 10
MARFA TX 81 48 81 38 / 10 10 0 0
MIDLAND INTL AIRPORT TX 90 65 86 42 / 10 10 0 0
ODESSA TX 90 64 85 42 / 10 10 0 0
WINK TX 91 60 88 46 / 10 10 0 0
&&
.MAF WATCHES/WARNINGS/ADVISORIES...
NM...FIRE WEATHER WATCH from Sunday morning through Sunday evening
FOR THE FOLLOWING ZONES... Guadalupe Mountains NP/Lincoln
NF/LNZ...Southeast Plains/BLM Roswell/LNZ.
RED FLAG WARNING from 11 AM this morning to 9 PM MDT this
evening FOR THE FOLLOWING ZONES... Guadalupe Mountains
NP/Lincoln NF/LNZ...Southeast Plains/BLM Roswell/LNZ.
TX...FIRE WEATHER WATCH from Sunday morning through Sunday evening
FOR THE FOLLOWING ZONES... Andrews...Big Bend Area...
Borden...Crane...Davis/Apache Mountains Area...Dawson...
Ector...Gaines...Glasscock...Guadalupe Mountains...Howard...
Loving...Marfa Plateau...Martin...Midland...Mitchell...
Pecos...Presidio Valley...Reagan...Reeves County and Upper
Trans Pecos...Scurry...Terrell...Upton...Van Horn and
Highway 54 Corridor...Ward...Winkler.
RED FLAG WARNING from Noon CDT /11 AM MDT/ today to 10 PM CDT /9
PM MDT/ this evening FOR THE FOLLOWING ZONES... Dawson...
Gaines...Guadalupe Mountains...Reeves County and Upper
Trans Pecos...Van Horn and Highway 54 Corridor.
&&
$$
72/13
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
934 AM EDT SAT APR 12 2014
.SYNOPSIS...
A WEAK FRONT WAS STALLED FROM NEW JERSEY TO NORTHERN KENTUCKY THIS
MORNING. THIS FRONT WILL SINK INTO EASTERN VIRGINIA TODAY BEFORE
MOVING BACK NORTH AS A WARM FRONT TONIGHT. A MUCH STRONGER COLD
FRONT WILL PUSH THROUGH THE AREA FROM THE WEST ON TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM EDT SATURDAY...
NOT MUCH CHANGE FROM PREVIOUS FORECAST PACKAGE. TWEAKED THE NEAR
TERM TEMPS HOWEVER STILL THINKING HIGHS IN THE UPPER 70S TO LOWER
80S FOR MOST AREAS. LATEST HRRR RUN STILL SHOWS THE CHANCE OF
SCATTERED SHOWERS ACROSS THE MOUNTAINS LATE THIS AFTERNOON SO LEFT
LOW POPS IN THROUGH EARLY EVENING.
AS OF 400 AM EDT SATURDAY...
SHORT WAVE OVER MOVING INTO ALABAMA AND GEORGIA WITH JUST A FEW
SHOWERS LEFT. OTHERWISE HEIGHTS RISING AT 500 MB TODAY AND TONIGHT.
AT THE SURFACE WEAK BOUNDARY MOVES BACK NORTH. SURFACE AND LOW LEVEL
WINDS BECOME SOUTH TO SOUTHEAST. MAY BE ENOUGH UPSLOPE ALONG THE
BLUE RIDGE AND SURFACE CONVERGENCE WHILE THE FRONT IS STILL IN THE
FORECAST AREA FOR ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON
AND EVENING. MODELS WERE FORECASTING CAPES FROM 800-1000 J/KG.
BUFKIT SHOWING A DEEP ENOUGH LAYER OF MOISTURE BELOW 10KFT TO
SUPPORT SHOWERS. CHALLENGING TO NARROW DOWN WHERE THREAT OF
PRECIPITATION IS THIS AFTERNOON...BUT ALLEGHANY HIGHLANDS LOOK LIKE
THE MOST LIKELY REGION WITH THE BEST CHANCE OF PRECIPITATION.
WITH THE LOSS OF HEATING THIS EVENING ANY REMAINING PRECIPITATION
AND CLOUD COVER WILL DISSIPATE. FORECAST AREA WILL BE WELL WITHIN THE
WARM AIR SOUTH OF THE FRONT. BOTH MET/MAV GUIDANCE LOOKED REASONABLE.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
AS OF 330 AM EDT SATURDAY...
STRONG SOUTHERLY FLOW BETWEEN HIGH PRESSURE OFFSHORE AND AN
APPROACHING COLD FRONT WILL MAKE FOR ANOTHER WARM DAY ON SUNDAY...
AS AFTERNOON TEMPERATURES CLIMB INTO THE MID/UPPER 70S ACROSS THE
MOUNTAINS AND INTO THE LOW 80S FURTHER EAST. WITH ABUNDANT SUNSHINE
TO START THE DAY TO PRODUCE MODEST INSTABILITY...IN ADDITION TO
INCREASING ATMOSPHERIC MOISTURE...MAY SEE A FEW SHOWERS DEVELOP
ALONG THE RIDGELINES...POSSIBLY AN ISOLATED WEAK THUNDERSTORM.
MODELS DO NOT SEEM TOO IMPRESSED WITH CHANCES FOR CONVECTION
HOWEVER...SO WILL STICK WITH VERY LOW RAIN CHANCES FOR NOW. MID AND
HIGH CLOUDS WILL INCREASE DURING THE EVENING AS THE COLD FRONT
PUSHES EAST OF THE MISSISSIPPI RIVER...AND BELIEVE WE MAY SEE A FEW
LIGHT SHOWERS OR AREAS OF DRIZZLE DEVELOP ALONG THE BLUE RIDGE
TOWARD DAWN TUESDAY. EXPECT OVERNIGHT LOWS TO HOLD IN THE 50S.
BELIEVE THAT SHOWER ACTIVITY WILL START MONDAY RATHER HIT AND MISS
AND BRIEF IN DURATION...MAINLY AFFECTING THE MOUNTAINS. HOWEVER...
SHOWERS WILL BECOME INCREASINGLY WIDESPREAD FROM WEST TO EAST DURING
THE AFTERNOON AS WEAK UPPER LEVEL DISTURBANCES PASS ACROSS THE AREA
FROM THE SOUTHWEST. MAY SEE A FEW THUNDERSTORMS DEVELOP...ALTHOUGH
INSTABILITY DOES NOT APPEAR TO BE THAT IMPRESSIVE DURING THE
AFTERNOON DUE TO INCREASED CLOUD COVER AND SHOWER ACTIVITY EARLY IN
THE DAY. SLIGHTLY BETTER CHANCES FOR ANY THUNDERSTORMS WILL BE EAST
OF THE BLUE RIDGE...ESPECIALLY IF CLOUD COVER MANAGES TO BREAK FOR
AN EXTENDED PERIOD OF TIME...BUT IT DOES NOT SEEM LIKELY. AFTERNOON
HIGHS WILL CLIMB INTO THE UPPER 60S TO MID 70S AREAWIDE.
THE COLD FRONT WILL ENTER OUR SOUTHEAST WEST VIRGINIA AND MOUNTAIN
EMPIRE COUNTIES SHORTLY BEFORE SUNRISE TUESDAY MORNING...AND WILL
PASS EAST ACROSS OUR AREA...EXITING OUR EASTERN-MOST COUNTIES BY MID
AFTERNOON. MODELS ARE STILL TRYING TO RESOLVE THE TIMING OF A WAVE
OF LOW PRESSURE RIDING NORTH ALONG THE FRONT FROM THE CAROLINAS ON
TUESDAY AFTERNOON...WHICH HAS THE POTENTIAL OF BRINGING PERIODS OF
HEAVY RAIN TO THE AREA. THE GFS FORECAST MODEL TENDS TO PUSH COLD
FRONTS ACROSS THE MID ATLANTIC A LITTLE TOO QUICKLY...AND THEREFORE
WILL STICK CLOSER TO THE SLOWER ECMWF MODEL TIMING...WHICH BRINGS
THE WAVE ACROSS THE PIEDMONT DURING LATE AFTERNOON INTO THE EVENING.
HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT...BUT MAY NOT SEE
RESIDUAL SHOWER ACTIVITY TOTALLY EXIT THE AREA TUESDAY NIGHT AS YET
ANOTHER WAVE PASSES NORTH ALONG THE FRONT...THIS ONE OFF THE
ATLANTIC COAST.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 345 PM EDT FRIDAY...
EXPECT HIGH PRESSURE TO CONTROL THE WEATHER PATTERN FOR WEDNESDAY
THROUGH FRIDAY. CHANGE IN AIRMASS WILL BRING COOL DRY CONDITIONS TO
THE AREA WEDNESDAY AND THURSDAY WITH POTENTIAL FOR A COUPLE OF
FROSTY MORNINGS. MODERATING TEMPERATURES WILL BEGIN TOWARD NEXT
WEEKEND AS THE AIRMASS BEGINS TO MODIFY.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
AS OF 730 AM EDT SATURDAY...
A NARROW STRIP OF MVFR CLOUDS HAD BANKED UP AGAINST THE WESTERN
SLOPES OF THE APPALACHIANS THIS MORNING...SO KBLF BRIEFLY HAD AN
MVFR CEILING. PATCHY DENSE FOG ALSO DEVELOP THIS MORNING IN SOME
OF THE WESTERN VALLEYS INCLUDING AT KLWB. OTHERWISE SATELLITE
PICTURES SHOWED SCATTERED TO BROKEN HIGH CLOUDS...ALL
VFR. HIGH CONFIDENCE THAT FOG AND MVFR CLOUDS WILL DISSIPATE BY
14Z/10AM.
WITH A WEAK FRONT NEARBY...EXPECT HEATING TO PRODUCE A BROKEN VFR CU
FIELD THIS AFTERNOON. ISOLD LIGHT SHOWERS ARE POSSIBLE...ESPCLY
OVER THE MOUNTAINS BY MID/LATE AFTERNOON...AS SEEN ON THE LOCAL
WRF AND HRRR. LEFT OUT MENTION OF ANY SHOWERS FOR NOW SINCE
COVERAGE WILL BE ISOLATED. WINDS TURN BACK SOUTH AROUND 10 KTS AS
THE SURFACE FRONT RECEDES BACK TO THE NORTH.
SUNDAY AND EARLY MONDAY SHOULD SEE A RETURN TO VFR FOR ALL SITES.
MONDAY NIGHT...A POTENT COLD FRONT WILL ARRIVE FROM THE WEST TO
TRIGGER A CHANCE OF SHOWERS AND THUNDERSTORMS...SOME WITH IFR/MVFR
CONDITIONS BY TUESDAY MORNING. SHOWERS LOOK TO CONTINUE INTO
TUESDAY...WITH WIDESPREAD MVFR/IFR LIKELY AT THIS POINT INTO
TUESDAY NIGHT. DRIER AIR LOOKS TO WORK IN BEHIND THE SYSTEM FOR
WEDNESDAY ALTHOUGH RESIDUAL MOISTURE AND COLD AIR ALOFT MAY ACT TO
KEEP MVFR CIGS OVER THE MOUNTAINS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/CF
SHORT TERM...NF
LONG TERM...PM
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
148 AM EDT SAT APR 12 2014
.SYNOPSIS...
A WEAK COLD FRONT WILL STALL OVER THE MID ATLANTIC REGION TONIGHT
BEFORE MOVING BACK NORTH AS A WARM FRONT THIS WEEKEND. A MUCH
STRONGER COLD FRONT WILL PUSH THROUGH THE AREA FROM THE WEST MONDAY
NIGHT AND TUESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 855 PM EDT FRIDAY...
PRE-FRONTAL BAND OF SHRA/TSRA HAS PUSHED EAST TO NEAR THE BLUE
RIDGE BUT FADING UPON ENCOUNTERING DRY AIR SEEN IN THE SFC- 7H
LAYER OFF THE RNK EVENING RAOB. ACTUAL FRONT REMAINS BACK ALONG
THE OHIO RIVER AND WILL ONLY DRIFT SE REACHING THE CENTRAL CWA BY
EARLY SATURDAY. THIS MAY KEEP ISOLATED SHRA GOING ESPCLY ALONG THE
RESIDUAL OUTFLOW A WHILE LONGER ESPCLY NE SECTIONS BEFORE THINGS
DRY OUT OVERNIGHT PER LATEST HRRR SOLUTION. HOWEVER IMPULSE NOW
TRACKING ACROSS TN/KY WITH MORE ORGANIZED CONVECTION WILL HAVE TO
BE WATCHED AS IT SCOOTS INTO SRN/CENTRAL N CAROLINA LATE. THUS MAY
LEAVE IN SOME LOW CHANCE TO SLIGHT POPS CENTRAL AND SW A WHILE
LONGER WHILE LOWERING NW WHERE APPEARS COVERAGE WILL BE QUITE A
BIT LESS BEHIND THE INITIAL BAND. ALSO INCLUDED PATCHY FOG OVER
THE FAR WEST AND NORTH WHERE SOME RAIN DID OCCUR WHILE BUMPING UP
CLOUD COVER ESPCLY BEFORE MIDNIGHT. TEMPS TO REMAIN MILD AHEAD OF
THE FRONT AND UNDER CLOUDS WITH MOST ALONG/EAST OF THE BLUE RIDGE
STAYING IN THE 50S OVERNIGHT.
PREVIOUS DISCUSSION AS OF 330 PM EDT FRIDAY...
A WEAK COLD FRONT ASSOCIATED WITH A DEPARTING SURFACE CYCLONE IS
LOCATED TO OUR NORTHWEST THIS AFTERNOON FROM CENTRAL PENNSYLVANIA
SOUTHWEST ALONG THE OHIO RIVER BACK INTO THE ARKLATEX. MOISTURE
ALONG THIS BOUNDARY IS SHALLOW AND FIGHTING DRY AIR BUT SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS HAVE BEEN FORMING AHEAD AND ALONG
IT. KEPT THE HIGHEST POPS IN THE NORTHWEST AS SUPPORTED BY NAM...GFS
AND RNK WRFARW FOR TONIGHT. THE ECMWF HOLD MOST OF THE MOISTURE IN
THE NORTHWEST. ALLOWED FOR SOME ISOLATED POPS TO PUSH A LITTLE
FURTHER SOUTH TONIGHT. WITH A DRY AIRMASS IN PLACE...SOUTHERN
PORTIONS OF CWA WILL REMAIN DRY. PLAYED LOW TEMPERATURES CLOSE TO
THE ADJMAVBC WITH READINGS FROM THE LOWER 40S IN THE MOUNTAINS TO
AROUND 50 DEGREES IN THE PIEDMONT.
THE WASHOUT OR DISSIPATING FRONT WILL LIFT NORTHWARD ON SATURDAY.
BELIEVE THE GFS IS OVERDONE WITH QPF/POPS ASSOCIATED UPPER LEVEL
SHORTWAVE TRACKING EAST. KEPT FORECAST DRY AS INDICATED BY NAM AND
ECMWF. SOUTHERLY FLOW WILL ALLOW HIGH TEMPERATURES SATURDAY TO CLIMB
INTO THE MID 60S IN THE MOUNTAINS TO AROUND 80 DEGREES IN THE
PIEDMONT.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
AS OF 330 PM EDT FRIDAY...
STRONG WARM AIR ADVECTION ANTICIPATED FOR SUNDAY AND MONDAY AS
SOUTHWEST WINDS INCREASE ACROSS THE AREA PER DEEPENING UPPER
LEVEL TROUGH EXITING THE ROCKIES AND RIDGE OF HIGH PRESSURE ALONG
THE SOUTHEAST ATLANTIC COAST. SUNDAY AFTERNOON WILL FEEL ALMOST
SUMMERLIKE WITH TEMPERATURES WARMING 10 TO 15 DEGREES ABOVE
NORMAL...READINGS CLIMBING INTO THE 80S ALONG AND EAST OF THE BLUE
RIDGE. MONDAY MAY FEATURE MORE OF THE SAME IF THE WESTERN STORM
SYSTEM WILL SLOW DOWN ITS APPROACH. CURRENT FCST IS FOR INCREASING
CLOUD COVER MONDAY WHICH WOULD SHAVE OFF ABOUT 5 DEGREES FROM WHAT
COULD BE AN EQUALLY WARM DAY.
THE SURFACE FRONT ASSOCIATED WITH THE UPPER TROUGH WILL BE MOVING
ACROSS THE MS VALLEY MONDAY. GULF MOISTURE IS PROGGED TO BE
FLOWING READILY NORTHWARD RESULTING IN RISING DEWPOINTS AND PROVIDING
FUEL FOR BOTH FRONTAL AND PREFRONTAL SHOWERS AND THUNDERSTORMS.
PREFRONTAL SHOWERS MAY REACH OUR FCST AREA AS EARLY AS MONDAY
AFTERNOON...BUT THESE SHOULD BE SCATTERED IN NATURE. THE MORE
WIDESPREAD THREAT FOR WETTING SHOWERS IS EXPECTED MONDAY NIGHT
AND TUESDAY AS THE ACTUAL COLD FRONT MOVES ACROSS THE REGION.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 345 PM EDT FRIDAY...
WET DAY ANTICIPATED TUESDAY AS BOTH THE UPPER LEVEL TROUGH AND
SURFACE FRONT MOVE ACROSS THE FORECAST AREA. THE ENTIRE SYSTEM IS
EXPECTED TO MOVE OFF THE COAST TUESDAY NIGHT WITH HIGH PRESSURE
BUILDING OVERHEAD FOR WEDNESDAY THROUGH FRIDAY. CHANGE IN AIRMASS
WILL BRING COOL DRY CONDITIONS TO THE AREA WEDNESDAY AND THURSDAY
WITH POTENTIAL FOR A COUPLE OF FROSTY MORNINGS. MODERATING
TEMPERATURES WILL BEGIN TOWARD NEXT WEEKEND AS THE AIRMASS BEGINS
TO MODIFY.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 145 PM EDT FRIDAY...
SCATTERED TO BROKEN LAYER OF MID TO HIGH CLOUDS...ALL
VFR...MOVING THROUGH THE MOUNTAINS AS A SHORT WAVE TRACK FROM
CENTRAL TENNESSEE TO SOUTH CAROLINA. HIGH CONFIDENCE THAT THE
PRECIPITATION WITH THIS WAVE WILL STAY SOUTH OF BLF AND BCB.
MAY SEE SOME FOG DEVELOP EARLY THIS MORNING AS CLOUDS MOVE OUT OF
THE AREA. LOW CONFIDENCE AT KLWB ABOUT FORMATION OF ANY DENSE FOG
ALONG THE GREENBRIER RIVER.
MODELS INDICATE SOME POTENTIAL FOR A PERIOD OF LOW CONDITIONS IN
STRATUS/FOG LATE TONIGHT AS FAR EAST AS KBCB GIVEN RESIDUAL
MOISTURE AND A WESTERLY TRAJECTORY AT KBLF. SINCE APPEARS AT LEAST
THE SE WVA SITES WILL SEE -SHRA WENT AHEAD AND INCLUDED A LATE
NIGHT/DAWN PERIOD OF MVFR AT KBLF.
EXPECT ANY LOW CIGS OR VSBYS TO SCOUR OUT BY MID MORNING PROVIDING
FOR OVERALL VFR INTO THE AFTERNOON. HOWEVER WITH THE FRONT
NEARBY...EXPECT HEATING TO PRODUCE A WIDESPREAD CU FIELD WITH
PERHAPS ISOLD SHRA/-TSRA AROUND ESPCLY OVER THE MOUNTAINS BY
MID/LATE AFTERNOON. LEFT OUT MENTION OF ANY SHOWERS FOR NOW SINCECOVERAGE
WILL BE ISOLATED. WINDS TURN BACK SOUTHERLY AROUND 10 KTS AS THE
SURFACE FRONT RECEDES BACK TO THE NORTH.
.EXTENDED AVIATION DISCUSSION...
SUNDAY AND EARLY MONDAY SHOULD SEE A RETURN TO VFR FOR ALL SITES.
BY MONDAY AFTERNOON...A POTENT COLD FRONT WILL ARRIVE FROM THE
WEST TO TRIGGER A CHANCE OF SHOWERS AND THUNDERSTORMS...SOME WITH
IFR/MVFR CONDITIONS BY EVENING. SHOWERS LOOK TO CONTINUE INTO
TUESDAY...WITH WIDESPREAD MVFR/IFR LIKELY AT THIS POINT INTO
TUESDAY NIGHT. DRIER AIR LOOKS TO WORK IN BEHIND THE SYSTEM FOR
WEDNESDAY ALTHOUGH RESIDUAL MOISTURE AND COLD AIR ALOFT MAY ACT TO
KEEP MVFR CIGS AROUND ESPCLY OVER THE MOUNTAINS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/KK
NEAR TERM...JH/KK
SHORT TERM...PM
LONG TERM...PM
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
632 PM CDT SUN APR 13 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 343 PM CDT SUN APR 13 2014
BUSY PERIOD TONIGHT INTO TOMORROW MORNING AS A LOW PRESSURE SYSTEM
TRACKS THROUGH NORTHERN ILLINOIS. HEAVY RAIN...SNOW...AND STRONG
WINDS ARE ALL CONCERNS TONIGHT INTO TOMORROW MORNING.
CURRENTLY...THE LEAD MID LEVEL TROUGH IS PROPAGATING TO THE NORTH
ACROSS THE MID-MISSISSIPPI RIVER VALLEY WITH SOME LOW LEVEL
CONVERGENCE OCCURRING ALONG A SOUTHWEST TO NORTHEAST ORIENTED WARM
FRONT THAT RUNS FROM SOUTHEAST IOWA THROUGH SOUTHERN WISCONSIN.
MODERATE TO HEAVY RAIN HAS ALREADY MOVED INTO NORTHEAST IOWA AND
SOUTHWEST WISCONSIN AND WILL CONTINUE TO TRACK TO THE NORTHEAST
INTO THIS EVENING AS THE SURFACE LOW MOVES UP IN THE REGION. MOST
OF THE 0-3KM MUCAPE THAT THE 13.19Z RAP SHOWS STAYS IN NORTHERN
ILLINOIS AND DOES NOT REACH THE REGION. SO...THINKING THAT THERE
SHOULD NOT BE MUCH LIGHTNING WITH THIS RAIN INTO THE EVENING
HOURS. WITH 1 TO 2 INCHES OF RAIN STILL FORECAST FOR THE SAME
AREAS THAT WERE HIT BY 1 TO 3 INCHES OF RAIN YESTERDAY...HAVE KEPT
THE FLOOD WATCH GOING FOR NORTHEAST IOWA AND SOUTHWEST WISCONSIN.
TO THE WEST SIDE OF THE SYSTEM WE GO WHERE THE CONCERN IS ON WHEN
THE THERMAL PROFILE WILL COOL ENOUGH TO CHANGE THE PRECIPITATION
OVER TO ALL SNOW ALONG WITH HOW WINDY IT WILL BE. IN REGARD TO THE
SNOW...WITH LOW TO MID LEVEL COLD AIR ADVECTION KICKING IN THIS
EVENING AS THE LOW DEEPENS...THE PRECIPITATION TYPE WILL BE
DEPENDENT UPON WHAT THE SURFACE TEMPERATURES ARE. LOOKING OUT WEST
RIGHT NOW...MOST OBSERVATIONS THAT ARE REPORTING SNOW ARE IN THE
30F TO 35F RANGE THOUGH SOME OF THESE TEMPERATURE DROPS APPEAR TO
BE DUE TO EVAPORATIVE COOLING THANKS TO THE PRECIPITATION FALLING
THROUGH THE COLUMN. BASED ON THE 13.19Z RAP & 13.12Z NAM/GFS
SOUNDINGS...IT LOOKS LIKE THE CHANGE OVER SHOULD OCCUR TO ALL SNOW
THIS EVENING BETWEEN 8-10PM IN NORTH CENTRAL IOWA AND SOUTHEAST
MINNESOTA. THIS CHANGE OVER WILL THEN GRADUALLY PUSH EASTWARD INTO
WESTERN WISCONSIN OVERNIGHT. SNOW TOTALS ARE PROBLEMATIC AS A
RESULT SINCE A LOT HINGES ON HOW FAST THE CHANGE OVER OCCURS...IS
THERE STRONG FORCING STILL THERE AS THE COLD AIR ARRIVES...AND
ALSO IF THERE EVEN IS ICE THERE AS A LOT OF THE SOUNDINGS SHOW A
DRY LAYER BETWEEN -8C TO -20C. MOST OF THE 13.12Z COBB DATA FROM
THE NAM/GFS IS SHOWING ABOUT 1 TO 2 INCHES OCCURRING OVERNIGHT
THOUGH A LOT OF THE SREF DATA IS MUCH HIGHER THAN THAT. GIVEN THE
NUMBER OF NEGATIVES WORKING AGAINST THIS...TRENDED TOWARD THESE
LOWER TOTALS WHICH STILL ARE A BIT HIGHER THAN WHAT PREVIOUSLY WAS
BEING FORECAST BY GUIDANCE. THE MAIN SNOW SHOULD FALL BETWEEN
7PM-1AM IN NORTHEAST IOWA/SOUTHEAST MINNESOTA AND THEN BETWEEN
1AM-7AM IN WESTERN WISCONSIN/FAR NORTHEAST IOWA.
WINDS WILL CONTINUALLY INCREASE THROUGH TONIGHT AS THE PRESSURE
GRADIENT TIGHTENS UP WITH THE LOW. THE STRONGEST LOW LEVEL WINDS
HAVE ALREADY DEVELOPED ACROSS WESTERN IOWA WHERE 30 TO 40KT WINDS
ARE FAIRLY WIDESPREAD IN THE AREA WHERE SNOW IS FALLING. CONCERNED
THAT THESE CONDITIONS WILL TRANSLATE EASTWARD INTO NORTHEAST IOWA
AND SOUTHEAST MINNESOTA THIS EVENING. THE STRONGEST WINDS LOOK
LIKE THEY WILL MAINLY BE IN NORTHEAST IOWA WITH BUFKIT SOUNDINGS
SHOWING SOME 35 TO 40KT WINDS MIXING DOWN AS THE SNOW IS COMING
DOWN. DISCUSSED THE IDEA OF DOING A WINTER WEATHER OR WIND ADVISORY
WITH MPX/DMX...BUT DECIDED THAT THE WIND GUSTS MAY NOT HIT
ADVISORY CRITERIA AND SNOW AMOUNTS MAY NOT BE HIGH ENOUGH TO CAUSE
A LARGE IMPACT. CONDITIONS WILL HAVE TO BE MONITORED CLOSELY THIS
EVENING FOR A POSSIBLE QUICK UPGRADE WITH THE 9PM TO 3AM TIME
FRAME THE MAIN PERIOD OF CONCERN.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 343 PM CDT SUN APR 13 2014
THE MAIN STORIES THROUGH THIS WEEK ARE WITH THE POTENTIAL
ACCUMULATING SNOW ON TUESDAY NIGHT/WEDNESDAY AND ANOTHER SYSTEM
LATER IN THE WEEK.
MORE FOCUS WENT INTO THE TUESDAY NIGHT/WEDNESDAY SYSTEM SINCE
THERE IS QUITE A BIT OF UNCERTAINTY WITH THE LATE WEEK SYSTEM. THE
13.12Z NAM/GFS DEVELOPS A BAND OF SNOW ACROSS NORTHERN WISCONSIN
LATE TUESDAY NIGHT WHILE THE 13.12Z ECMWF KEEPS US DRY. SOME
ACCUMULATING SNOW IS LIKELY IN THE NAM/GFS SCENARIOS THOUGH ENOUGH
UNCERTAINTY IS THERE THANKS TO THE ECMWF. IT LOOKS LIKE WE GET
WARM SECTORED ON WEDNESDAY AS THE SYSTEM STALLS OUT WITH THE
PRECIPITATION SETTING UP FROM UPPER MICHIGAN DOWN THROUGH CENTRAL
IOWA ON THURSDAY. THE 13.12Z GFS THEN SPINS UP A POTENT SYSTEM FOR
FRIDAY THAT TRACKS THROUGH WISCONSIN WHILE EH ECMWF HARDLY HAS A
LOW DEVELOPING.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 632 PM CDT SUN APR 13 2014
WIDESPREAD RAIN CONTINUES FOR AREA LEADING TO MIX OF IFR AND MVFR
CONDITIONS. AS SURFACE LOW TRACKS BY TO THE SOUTH THIS EVENING...
COLDER AIR WILL CHANGE RAIN OVER TO SNOW FROM WEST TO EAST AND
CONDITIONS WILL WORSEN TO LIFR FOR A PERIOD OF TIME WITH LIGHT SNOW
ACCUMULATION. IN ADDITION NORTH TO NORTHWEST WINDS WILL BE ON THE
INCREASE AND COULD SEE GUSTS OF 30 MPH OR HIGHER AT TIMES GOING INTO
MONDAY MORNING.
ONCE PRECIPITATION BEGINS TO SHIFT EAST OVERNIGHT...EXPECT PRETTY
GOOD RECOVERY WITH MVFR CONDITIONS DURING THE MORNING...EVOLVING TO
VFR AS DRIER AIR MIXES IN.
&&
.HYDROLOGY...
ISSUED AT 343 PM CDT SUN APR 13 2014
WITH MODERATE TO AT TIMES HEAVY RAIN FALLING INTO TONIGHT...WILL
KEEP THE FLOOD WATCH GOING FOR NORTHEAST IOWA AND SOUTHWEST
WISCONSIN. WITH 1 TO 3 INCHES OF RAIN FALLING LAST NIGHT ACROSS
THIS AREA AND ANOTHER 1 TO 2 INCHES POSSIBLE...SAW NO NEED TO DROP
IT. THERE DOES NOT APPEAR TO BE MUCH INSTABILITY THAT MAKES IT UP
IN THE REGION THIS AFTERNOON INTO TONIGHT...SO MOST OF THE RAIN
SHOULD NOT FALL AT A GREAT ENOUGH OF A RATE TO PROMPT FLASH
FLOODING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLOOD WATCH UNTIL 1 AM CDT MONDAY FOR WIZ043-044-053>055-061.
MN...NONE.
IA...FLOOD WATCH UNTIL 1 AM CDT MONDAY FOR IAZ030.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...SHEA
HYDROLOGY...HALBACH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1259 PM CDT SAT APR 12 2014
.UPDATE...
ISSUED AT 1259 PM CDT SAT APR 12 2014
AN INITIAL ROUND OF CONVECTION CAME THROUGH THIS MORNING ALONG THE
NOSE OF THE LOW LEVEL JET/WARM AIR ADVECTION THAT HAS NOW SHIFTED
FURTHER EAST INTO CENTRAL WISCONSIN. OUTFLOW FROM THESE STORMS HAS
REINFORCED A WARM FRONT BOUNDARY THAT CURRENTLY EXTENDS FROM ALONG
NORTH CENTRAL IOWA THROUGH NORTHEAST IOWA TO GRANT COUNTY
WISCONSIN. TEMPERATURES AND DEW POINTS SOUTH OF THE WARM FRONT
HAVE QUICKLY JUMPED INTO THE 70S/50S WHILE TEMPERATURES NORTH OF
THE FRONT IN THE RAIN COOLED AIR MASS ARE STUCK IN THE 40S.
THE AIR MASS SOUTH OF THE FRONT IS BECOMING MORE UNSTABLE...BUT
THE CONVECTIVE INHIBITION HAS BEEN HIGH ENOUGH TO KEEP STORMS FROM
FIRING...BUT AS A MID LEVEL SHORT WAVE TROUGH AND SURFACE LOW
MOVES INTO THE REGION THIS AFTERNOON EXPECT THAT STORMS WILL
INITIATE ALONG THE FRONT. WITH THE 12.16Z RAP SHOWING AROUND
2000 J/KG OF MUCAPE DEVELOPING WITH 0-6KM SHEAR OF 50KTS
WILL BE SUPPORTIVE OF SUPERCELL STORM MODE. THE WIND SHEAR WILL
MAINLY BE UNIDIRECTIONAL IN THE WARM SECTOR WITH SURFACE WINDS OUT
OF THE SOUTHWEST AND MID LEVEL WINDS OUT OF THE WEST...SO NOT MUCH
OF A TORNADO THREAT IS ANTICIPATED. LARGE HAIL LOOKS TO BE THE
MAIN CONCERN WITH A TRANSITION TO STRAIGHTLINE WINDS THIS EVENING
THOUGH THAT TRANSITION MAY OCCUR FURTHER SOUTH IN EAST CENTRAL
IOWA/NW ILLINOIS. SO...BASED ON THIS FORECAST...EXPECT THAT THERE
WILL BE A SECOND ROUND OF SEVERE WEATHER THIS AFTERNOON INTO THIS
EVENING...MAINLY ACROSS NORTHEAST IOWA AND SOUTHWEST WISCONSIN.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 316 AM CDT SAT APR 12 2014
THE MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES
THROUGH THE PERIOD.
WATER VAPOR SATELLITE THIS MORNING SHOWS A SHORT WAVE TROUGH
MOVING ACROSS THE DAKOTAS. REGIONAL RADARS SHOW AN AREA OF SHOWERS
OUT AHEAD OF THE WAVE ACROSS NORTHERN MINNESOTA WITH A SMALLER
AREA OVER SOUTHEAST SOUTH DAKOTA AND NORTHWEST IOWA. THE 12.05Z
HRRR SEEMS TO HAVE A GOOD IDEA ABOUT THE ONGOING
ACTIVITY...ALTHOUGH IT MAY BE A LITTLE UNDERDONE WITH THE ACTION
AROUND OVER NORTHWEST IOWA. THE GENERAL TREND OF THE HRRR AND THE
12.00Z HI-RES ARW IS TO MOVE THE ACTIVITY ALMOST STRAIGHT EAST AS
THE SHORT WAVE TROUGH MOVES ACROSS MINNESOTA AND NORTHERN
WISCONSIN. HAVE TRENDED THE RAIN CHANCES FOR THIS MORNING TOWARD
THESE MESO MODELS WITH THE HIGHEST CHANCES ACROSS THE NORTHERN
SECTIONS CLOSER TO THE SHORT WAVE TROUGH WITH AT LEAST AT 30 TO 40
PERCENT CHANCE ACROSS THE SOUTH.
ONCE THIS ACTIVITY MOVES BY...THERE SHOULD BE A LULL IN THE
ACTIVITY AS THE REGION GETS IN BETWEEN SHORT WAVE TROUGHS FOR A
WHILE EARLY THIS AFTERNOON. THE NEXT SHORT WAVE THROUGH WILL THEN
START TO APPROACH FROM THE SOUTHWEST FOR LATE THIS AFTERNOON AND
MOVE ACROSS THE REGION THIS EVENING. THIS WAVE WILL BRING THE NEXT
ROUND OF FORCING PRODUCING SOME WEAK PV ADVECTION IN THE 500-300
MB LAYER. THE LOW LEVEL JET WILL INCREASE AHEAD OF THIS WAVE WITH
THE NOSE OF THE 850 MB MOISTURE TRANSPORT EXPECTED TO BE OVER
EASTERN IOWA AND INTO THE WEAK FRONT THAT GETS PUSHED INTO THE
AREA BY THIS MORNING/S ACTIVITY. THE 12.00Z NAM SHOWS THE WARM AIR
ADVECTION AHEAD OF THE WAVE PRODUCING BETWEEN 2 AND 6 UBAR/S OF UP
GLIDE INTO AND OVER THIS FRONT. THE HI-RES ARW SHOWS A LINE OF
CONVECTION FIRING UP DURING THE LATE AFTERNOON AND EVENING ALONG
THE FRONT OVER THE SOUTHERN SECTIONS OF THE FORECAST AREA. STILL
SOME UNCERTAINTY ON HOW MUCH MOISTURE WILL RETURN TO THE AREA AND
THUS THE AMOUNT OF CAPE THAT WILL BE AVAILABLE. HOWEVER...EXPECT
THAT THERE WILL BE ENOUGH CAPE TO SUPPORT STORMS AND EVEN THE
POSSIBILITY OF SOME SEVERE AS THERE WILL BE AMPLE SHEAR IN PLACE
WITH THE NAM SUGGESTING BETWEEN 50 AND 60 KNOTS IN THE 0-6KM
LAYER. APPEARS LARGE HAIL AND DAMAGING WINDS WOULD BE THE MAIN
THREAT WITH THE BEST LOW LEVEL HELICITY EXPECTED TO REMAIN WELL
SOUTH OF THE AREA.
ANOTHER LULL IN THE ACTIVITY IS THEN EXPECTED TO OCCUR DURING THE
OVERNIGHT HOURS UNTIL YET ANOTHER SHORT WAVE TROUGH COMES IN FROM
THE SOUTHWEST. THIS WAVE WILL COME ACROSS THE REGION SUNDAY AND
THE MODELS HAVE REMAINED CONSISTENT IN SHOWING THIS TO THE BE THE
STRONGEST OF ALL THE WAVES. IN ADDITION TO THE FORCING FROM THE
WAVE ITSELF...IT APPEARS THERE WILL BE SOME JET DYNAMICS WITH THE
POSSIBILITY OF BEING IN THE LEFT EXIT REGION OF THE JET COMING IN
WITH THE WAVE AND THE RIGHT ENTRANCE REGION OF THE NORTHERN STREAM
JET AXIS MOVING ALONG THE CANADIAN BORDER. WEAK TO MODERATE
FRONTOGENESIS SHOULD OCCUR IN THE 1000-500 MB LAYER ACROSS MAINLY
THE SOUTHERN PARTS OF THE AREA WITH THE SLOW MOVING FRONTAL
BOUNDARY STILL IN THE VICINITY. ANOTHER ROUND OF 2 TO 6 UBAR/S OF
ISENTROPIC UP GLIDE SHOULD OCCUR ON THE 295K SURFACE INTO AND OVER
THE FRONT. THIS PERIOD OF STRONG FORCING IS EXPECTED TO PRODUCE
WIDESPREAD RAINS FOR MOST OF THE REGION...ESPECIALLY SUNDAY
AFTERNOON AND WILL SHOW 75 TO 100 PERCENT RAIN CHANCES ROUGHLY
ALONG AND SOUTH OF INTERSTATE 90. THE HIGH PRECIPITATION CHANCES
WILL CONTINUE INTO SUNDAY EVENING ACROSS THE EASTERN PARTS OF THE
AREA...BUT WILL START TO DIMINISH FOR THE REST OF THE AREA AS THE
SHORT WAVE TROUGH AND FORCING STARTS TO MOVE PAST WITH THE
POSSIBILITY OF THE PRECIPITATION ENDING LATE SUNDAY NIGHT ACROSS
THE FAR WEST. THERE STILL LOOKS TO BE ENOUGH COLD AIR THAT COMES
IN AT THE END OF THE PRECIPITATION CHANCES FOR A CHANGE OVER TO
SOME LIGHT SNOW. ANY ACCUMULATIONS SHOULD BE LIMITED TO THE
SOUTHEAST PARTS OF THE AREA WITH AMOUNTS LESS THAN A HALF INCH.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 316 AM CDT SAT APR 12 2014
THE MODELS CONTINUE TO SHOW DIFFERING SOLUTIONS FOR THE MIDDLE AND
END OF THE UP COMING WEEK. ALL OF THE MODELS SHOW ENERGY MOVING
ON TO THE SOUTHWEST CANADIAN SHORE FROM THE PACIFIC TUESDAY. THE
12.00Z ECMWF THEN TAKES THIS WAVE EAST IN A NEARLY ZONAL FLOW. THE
12.00Z GFS AND THE GEM SHOW THIS WAVE MOVING SOUTHEAST AND FORMING
AN UPPER LEVEL LOW OVER THE CENTRAL ROCKIES BY WEDNESDAY NIGHT
WITH THE GFS CLOSING THIS LOW OFF WHILE THE GEM KEEPS IT AS AN
OPEN SYSTEM. ALL THE MODELS THEN SHOW THIS SYSTEM COMING ACROSS
THE CENTRAL PART OF THE COUNTY THURSDAY THROUGH FRIDAY...WHICH IS
GOOD TIMING CONSIDERING THE DIFFERENCES IN STRENGTH. FOR
NOW...WILL STAY WITH THE MODEL CONSENSUS GRIDS WHICH PRIMARILY
HAVE 20 TO 30 PERCENT PRECIPITATION CHANCES FOR WEDNESDAY THROUGH
FRIDAY. UNFORTUNATELY...TEMPERATURES LOOK TO REMAIN BELOW NORMAL
FOR NEXT WEEK WHICH WILL RESULT IN SNOW CHANCES AT NIGHT AND RAIN
CHANCES DURING THE DAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1259 PM CDT SAT APR 12 2014
MVFR TO IFR CONDITIONS EXPECTED AT THE TAF SITES THOUGH MOST OF
THE RAIN AND THUNDERSTORMS ARE EXPECTED TO STAY OFF TO THE
SOUTHEAST. SOME 2-3KFT CEILINGS HAVE SET UP ACROSS THE REGION AND
WILL LIKELY PERSIST THROUGH TONIGHT/TOMORROW MORNING. SOME RAIN
COULD GET INTO LSE THIS EVENING...BUT IS NOT EXPECTED AT RST.
WINDS WILL STAY OUT OF THE EAST-NORTHEAST THROUGH TOMORROW
MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...HALBACH
SHORT TERM...04
LONG TERM...04
AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
636 AM CDT SAT APR 12 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 316 AM CDT SAT APR 12 2014
THE MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES
THROUGH THE PERIOD.
WATER VAPOR SATELLITE THIS MORNING SHOWS A SHORT WAVE TROUGH
MOVING ACROSS THE DAKOTAS. REGIONAL RADARS SHOW AN AREA OF SHOWERS
OUT AHEAD OF THE WAVE ACROSS NORTHERN MINNESOTA WITH A SMALLER
AREA OVER SOUTHEAST SOUTH DAKOTA AND NORTHWEST IOWA. THE 12.05Z
HRRR SEEMS TO HAVE A GOOD IDEA ABOUT THE ONGOING
ACTIVITY...ALTHOUGH IT MAY BE A LITTLE UNDERDONE WITH THE ACTION
AROUND OVER NORTHWEST IOWA. THE GENERAL TREND OF THE HRRR AND THE
12.00Z HI-RES ARW IS TO MOVE THE ACTIVITY ALMOST STRAIGHT EAST AS
THE SHORT WAVE TROUGH MOVES ACROSS MINNESOTA AND NORTHERN
WISCONSIN. HAVE TRENDED THE RAIN CHANCES FOR THIS MORNING TOWARD
THESE MESO MODELS WITH THE HIGHEST CHANCES ACROSS THE NORTHERN
SECTIONS CLOSER TO THE SHORT WAVE TROUGH WITH AT LEAST AT 30 TO 40
PERCENT CHANCE ACROSS THE SOUTH.
ONCE THIS ACTIVITY MOVES BY...THERE SHOULD BE A LULL IN THE
ACTIVITY AS THE REGION GETS IN BETWEEN SHORT WAVE TROUGHS FOR A
WHILE EARLY THIS AFTERNOON. THE NEXT SHORT WAVE THROUGH WILL THEN
START TO APPROACH FROM THE SOUTHWEST FOR LATE THIS AFTERNOON AND
MOVE ACROSS THE REGION THIS EVENING. THIS WAVE WILL BRING THE NEXT
ROUND OF FORCING PRODUCING SOME WEAK PV ADVECTION IN THE 500-300
MB LAYER. THE LOW LEVEL JET WILL INCREASE AHEAD OF THIS WAVE WITH
THE NOSE OF THE 850 MB MOISTURE TRANSPORT EXPECTED TO BE OVER
EASTERN IOWA AND INTO THE WEAK FRONT THAT GETS PUSHED INTO THE
AREA BY THIS MORNING/S ACTIVITY. THE 12.00Z NAM SHOWS THE WARM AIR
ADVECTION AHEAD OF THE WAVE PRODUCING BETWEEN 2 AND 6 UBAR/S OF UP
GLIDE INTO AND OVER THIS FRONT. THE HI-RES ARW SHOWS A LINE OF
CONVECTION FIRING UP DURING THE LATE AFTERNOON AND EVENING ALONG
THE FRONT OVER THE SOUTHERN SECTIONS OF THE FORECAST AREA. STILL
SOME UNCERTAINTY ON HOW MUCH MOISTURE WILL RETURN TO THE AREA AND
THUS THE AMOUNT OF CAPE THAT WILL BE AVAILABLE. HOWEVER...EXPECT
THAT THERE WILL BE ENOUGH CAPE TO SUPPORT STORMS AND EVEN THE
POSSIBILITY OF SOME SEVERE AS THERE WILL BE AMPLE SHEAR IN PLACE
WITH THE NAM SUGGESTING BETWEEN 50 AND 60 KNOTS IN THE 0-6KM
LAYER. APPEARS LARGE HAIL AND DAMAGING WINDS WOULD BE THE MAIN
THREAT WITH THE BEST LOW LEVEL HELICITY EXPECTED TO REMAIN WELL
SOUTH OF THE AREA.
ANOTHER LULL IN THE ACTIVITY IS THEN EXPECTED TO OCCUR DURING THE
OVERNIGHT HOURS UNTIL YET ANOTHER SHORT WAVE TROUGH COMES IN FROM
THE SOUTHWEST. THIS WAVE WILL COME ACROSS THE REGION SUNDAY AND
THE MODELS HAVE REMAINED CONSISTENT IN SHOWING THIS TO THE BE THE
STRONGEST OF ALL THE WAVES. IN ADDITION TO THE FORCING FROM THE
WAVE ITSELF...IT APPEARS THERE WILL BE SOME JET DYNAMICS WITH THE
POSSIBILITY OF BEING IN THE LEFT EXIT REGION OF THE JET COMING IN
WITH THE WAVE AND THE RIGHT ENTRANCE REGION OF THE NORTHERN STREAM
JET AXIS MOVING ALONG THE CANADIAN BORDER. WEAK TO MODERATE
FRONTOGENESIS SHOULD OCCUR IN THE 1000-500 MB LAYER ACROSS MAINLY
THE SOUTHERN PARTS OF THE AREA WITH THE SLOW MOVING FRONTAL
BOUNDARY STILL IN THE VICINITY. ANOTHER ROUND OF 2 TO 6 UBAR/S OF
ISENTROPIC UP GLIDE SHOULD OCCUR ON THE 295K SURFACE INTO AND OVER
THE FRONT. THIS PERIOD OF STRONG FORCING IS EXPECTED TO PRODUCE
WIDESPREAD RAINS FOR MOST OF THE REGION...ESPECIALLY SUNDAY
AFTERNOON AND WILL SHOW 75 TO 100 PERCENT RAIN CHANCES ROUGHLY
ALONG AND SOUTH OF INTERSTATE 90. THE HIGH PRECIPITATION CHANCES
WILL CONTINUE INTO SUNDAY EVENING ACROSS THE EASTERN PARTS OF THE
AREA...BUT WILL START TO DIMINISH FOR THE REST OF THE AREA AS THE
SHORT WAVE TROUGH AND FORCING STARTS TO MOVE PAST WITH THE
POSSIBILITY OF THE PRECIPITATION ENDING LATE SUNDAY NIGHT ACROSS
THE FAR WEST. THERE STILL LOOKS TO BE ENOUGH COLD AIR THAT COMES
IN AT THE END OF THE PRECIPITATION CHANCES FOR A CHANGE OVER TO
SOME LIGHT SNOW. ANY ACCUMULATIONS SHOULD BE LIMITED TO THE
SOUTHEAST PARTS OF THE AREA WITH AMOUNTS LESS THAN A HALF INCH.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 316 AM CDT SAT APR 12 2014
THE MODELS CONTINUE TO SHOW DIFFERING SOLUTIONS FOR THE MIDDLE AND
END OF THE UP COMING WEEK. ALL OF THE MODELS SHOW ENERGY MOVING
ON TO THE SOUTHWEST CANADIAN SHORE FROM THE PACIFIC TUESDAY. THE
12.00Z ECMWF THEN TAKES THIS WAVE EAST IN A NEARLY ZONAL FLOW. THE
12.00Z GFS AND THE GEM SHOW THIS WAVE MOVING SOUTHEAST AND FORMING
AN UPPER LEVEL LOW OVER THE CENTRAL ROCKIES BY WEDNESDAY NIGHT
WITH THE GFS CLOSING THIS LOW OFF WHILE THE GEM KEEPS IT AS AN
OPEN SYSTEM. ALL THE MODELS THEN SHOW THIS SYSTEM COMING ACROSS
THE CENTRAL PART OF THE COUNTY THURSDAY THROUGH FRIDAY...WHICH IS
GOOD TIMING CONSIDERING THE DIFFERENCES IN STRENGTH. FOR
NOW...WILL STAY WITH THE MODEL CONSENSUS GRIDS WHICH PRIMARILY
HAVE 20 TO 30 PERCENT PRECIPITATION CHANCES FOR WEDNESDAY THROUGH
FRIDAY. UNFORTUNATELY...TEMPERATURES LOOK TO REMAIN BELOW NORMAL
FOR NEXT WEEK WHICH WILL RESULT IN SNOW CHANCES AT NIGHT AND RAIN
CHANCES DURING THE DAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 636 AM CDT SAT APR 12 2014
FAIRLY COMPLEX FORECAST SETTING UP FOR THE KRST/KLSE TAF SITES.
CURRENTLY WATCHING A LARGE SHIELD OF SHRA/ISOLD T MOVING EAST
ACROSS MN/IA INTO WESTERN WI. THIS WAS TAKING PLACE AHEAD OF A LOW
PRESSURE SYSTEM OVER THE PLAINS AND A WARM FRONT HANGING AROUND
THE I-80 CORRIDOR. LOOK FOR THIS BATCH OF SHRA/ISOLD T TO PUSH
EAST INTO CENTRAL WI BY NOON. OTHERWISE...LOOKING FOR THE WARM
FRONT TO MOVE UP TO NEAR THE MN/IA BORDER WITH KLSE/KRST TAF SITES
REMAINING NORTH OF THE BOUNDARY TODAY. THIS WILL KEEP MAINLY VFR
CLOUD COVER IN PLACE AS SHRA ACTIVITY TAPERS OFF BY 15-17Z. MAY
HAVE TO WATCH FOR SOME MVFR AT KRST. SHRA/T EXPECTED TO REDEVELOP
SOUTH OF THE TAF SITES LATER THIS AFTERNOON...THEN LASTING INTO
TONIGHT. SOUTHEAST WINDS OF 10-15KT TO SWING OUT OF THE
NORTH/NORTHEAST BY THIS EVENING AS THE FRONTAL BOUNDARY SAGS BACK
TO THE SOUTH OVERNIGHT. COOLING IN THE BOUNDARY LAYER NORTH OF
THIS FRONTAL BOUNDARY WILL ALLOW SOME MVFR CATEGORY CLOUDS TO
FORM AT THE TAF SITES THROUGH THE OVERNIGHT HOURS. HAVE BKN025-030
GOING RIGHT NOW...BUT WILL KEEP AN EYE ON FOR POSSIBLY LOWER CIGS
THAN THIS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
316 AM CDT SAT APR 12 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 316 AM CDT SAT APR 12 2014
THE MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES
THROUGH THE PERIOD.
WATER VAPOR SATELLITE THIS MORNING SHOWS A SHORT WAVE TROUGH
MOVING ACROSS THE DAKOTAS. REGIONAL RADARS SHOW AN AREA OF SHOWERS
OUT AHEAD OF THE WAVE ACROSS NORTHERN MINNESOTA WITH A SMALLER
AREA OVER SOUTHEAST SOUTH DAKOTA AND NORTHWEST IOWA. THE 12.05Z
HRRR SEEMS TO HAVE A GOOD IDEA ABOUT THE ONGOING
ACTIVITY...ALTHOUGH IT MAY BE A LITTLE UNDERDONE WITH THE ACTION
AROUND OVER NORTHWEST IOWA. THE GENERAL TREND OF THE HRRR AND THE
12.00Z HI-RES ARW IS TO MOVE THE ACTIVITY ALMOST STRAIGHT EAST AS
THE SHORT WAVE TROUGH MOVES ACROSS MINNESOTA AND NORTHERN
WISCONSIN. HAVE TRENDED THE RAIN CHANCES FOR THIS MORNING TOWARD
THESE MESO MODELS WITH THE HIGHEST CHANCES ACROSS THE NORTHERN
SECTIONS CLOSER TO THE SHORT WAVE TROUGH WITH AT LEAST AT 30 TO 40
PERCENT CHANCE ACROSS THE SOUTH.
ONCE THIS ACTIVITY MOVES BY...THERE SHOULD BE A LULL IN THE
ACTIVITY AS THE REGION GETS IN BETWEEN SHORT WAVE TROUGHS FOR A
WHILE EARLY THIS AFTERNOON. THE NEXT SHORT WAVE THROUGH WILL THEN
START TO APPROACH FROM THE SOUTHWEST FOR LATE THIS AFTERNOON AND
MOVE ACROSS THE REGION THIS EVENING. THIS WAVE WILL BRING THE NEXT
ROUND OF FORCING PRODUCING SOME WEAK PV ADVECTION IN THE 500-300
MB LAYER. THE LOW LEVEL JET WILL INCREASE AHEAD OF THIS WAVE WITH
THE NOSE OF THE 850 MB MOISTURE TRANSPORT EXPECTED TO BE OVER
EASTERN IOWA AND INTO THE WEAK FRONT THAT GETS PUSHED INTO THE
AREA BY THIS MORNING/S ACTIVITY. THE 12.00Z NAM SHOWS THE WARM AIR
ADVECTION AHEAD OF THE WAVE PRODUCING BETWEEN 2 AND 6 UBAR/S OF UP
GLIDE INTO AND OVER THIS FRONT. THE HI-RES ARW SHOWS A LINE OF
CONVECTION FIRING UP DURING THE LATE AFTERNOON AND EVENING ALONG
THE FRONT OVER THE SOUTHERN SECTIONS OF THE FORECAST AREA. STILL
SOME UNCERTAINTY ON HOW MUCH MOISTURE WILL RETURN TO THE AREA AND
THUS THE AMOUNT OF CAPE THAT WILL BE AVAILABLE. HOWEVER...EXPECT
THAT THERE WILL BE ENOUGH CAPE TO SUPPORT STORMS AND EVEN THE
POSSIBILITY OF SOME SEVERE AS THERE WILL BE AMPLE SHEAR IN PLACE
WITH THE NAM SUGGESTING BETWEEN 50 AND 60 KNOTS IN THE 0-6KM
LAYER. APPEARS LARGE HAIL AND DAMAGING WINDS WOULD BE THE MAIN
THREAT WITH THE BEST LOW LEVEL HELICITY EXPECTED TO REMAIN WELL
SOUTH OF THE AREA.
ANOTHER LULL IN THE ACTIVITY IS THEN EXPECTED TO OCCUR DURING THE
OVERNIGHT HOURS UNTIL YET ANOTHER SHORT WAVE TROUGH COMES IN FROM
THE SOUTHWEST. THIS WAVE WILL COME ACROSS THE REGION SUNDAY AND
THE MODELS HAVE REMAINED CONSISTENT IN SHOWING THIS TO THE BE THE
STRONGEST OF ALL THE WAVES. IN ADDITION TO THE FORCING FROM THE
WAVE ITSELF...IT APPEARS THERE WILL BE SOME JET DYNAMICS WITH THE
POSSIBILITY OF BEING IN THE LEFT EXIT REGION OF THE JET COMING IN
WITH THE WAVE AND THE RIGHT ENTRANCE REGION OF THE NORTHERN STREAM
JET AXIS MOVING ALONG THE CANADIAN BORDER. WEAK TO MODERATE
FRONTOGENESIS SHOULD OCCUR IN THE 1000-500 MB LAYER ACROSS MAINLY
THE SOUTHERN PARTS OF THE AREA WITH THE SLOW MOVING FRONTAL
BOUNDARY STILL IN THE VICINITY. ANOTHER ROUND OF 2 TO 6 UBAR/S OF
ISENTROPIC UP GLIDE SHOULD OCCUR ON THE 295K SURFACE INTO AND OVER
THE FRONT. THIS PERIOD OF STRONG FORCING IS EXPECTED TO PRODUCE
WIDESPREAD RAINS FOR MOST OF THE REGION...ESPECIALLY SUNDAY
AFTERNOON AND WILL SHOW 75 TO 100 PERCENT RAIN CHANCES ROUGHLY
ALONG AND SOUTH OF INTERSTATE 90. THE HIGH PRECIPITATION CHANCES
WILL CONTINUE INTO SUNDAY EVENING ACROSS THE EASTERN PARTS OF THE
AREA...BUT WILL START TO DIMINISH FOR THE REST OF THE AREA AS THE
SHORT WAVE TROUGH AND FORCING STARTS TO MOVE PAST WITH THE
POSSIBILITY OF THE PRECIPITATION ENDING LATE SUNDAY NIGHT ACROSS
THE FAR WEST. THERE STILL LOOKS TO BE ENOUGH COLD AIR THAT COMES
IN AT THE END OF THE PRECIPITATION CHANCES FOR A CHANGE OVER TO
SOME LIGHT SNOW. ANY ACCUMULATIONS SHOULD BE LIMITED TO THE
SOUTHEAST PARTS OF THE AREA WITH AMOUNTS LESS THAN A HALF INCH.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 316 AM CDT SAT APR 12 2014
THE MODELS CONTINUE TO SHOW DIFFERING SOLUTIONS FOR THE MIDDLE AND
END OF THE UP COMING WEEK. ALL OF THE MODELS SHOW ENERGY MOVING
ON TO THE SOUTHWEST CANADIAN SHORE FROM THE PACIFIC TUESDAY. THE
12.00Z ECMWF THEN TAKES THIS WAVE EAST IN A NEARLY ZONAL FLOW. THE
12.00Z GFS AND THE GEM SHOW THIS WAVE MOVING SOUTHEAST AND FORMING
AN UPPER LEVEL LOW OVER THE CENTRAL ROCKIES BY WEDNESDAY NIGHT
WITH THE GFS CLOSING THIS LOW OFF WHILE THE GEM KEEPS IT AS AN
OPEN SYSTEM. ALL THE MODELS THEN SHOW THIS SYSTEM COMING ACROSS
THE CENTRAL PART OF THE COUNTY THURSDAY THROUGH FRIDAY...WHICH IS
GOOD TIMING CONSIDERING THE DIFFERENCES IN STRENGTH. FOR
NOW...WILL STAY WITH THE MODEL CONSENSUS GRIDS WHICH PRIMARILY
HAVE 20 TO 30 PERCENT PRECIPITATION CHANCES FOR WEDNESDAY THROUGH
FRIDAY. UNFORTUNATELY...TEMPERATURES LOOK TO REMAIN BELOW NORMAL
FOR NEXT WEEK WHICH WILL RESULT IN SNOW CHANCES AT NIGHT AND RAIN
CHANCES DURING THE DAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1018 PM CDT FRI APR 11 2014
A LOW PRESSURE SYSTEM OVER THE DAKOTAS WILL TRACK ACROSS THE TAF
SITES DURING THE NEXT 24 HOURS...WITH ITS WARM FRONT PASSING
THROUGH DURING THE MORNING AND THE COLD FRONT LATE IN THE
AFTERNOON. PLENTIFUL DRY AIR AROUND...EVEN DURING ALL OF THE
FRONTAL PASSAGES...SHOULD HELP TO KEEP CONDITIONS MOSTLY VFR FOR
THE TAFS. HOWEVER...THERE COULD BE A BRIEF PERIOD OF MVFR
VISIBILITIES AS SHOWERS MOVE THROUGH DURING THE 11-16Z PERIOD.
THESE SHOWERS COULD ALSO CONTAIN SOME THUNDER...BUT THE
PROBABILITY IS TOO LOW TO MENTION IN THE TAF AT THIS TIME.
ADDITIONAL SHOWERS COULD FIRE NEAR LSE AROUND MID AFTERNOON...BUT
CONFIENCE ONLY ALLOWS A VCSH RIGHT NOW.
A LOT OF CHANGES ARE EXPECTED WITH WIND DIRECTION AS THIS SYSTEM
TRACKS THROUGH...GOING FROM SOUTHEAST TO SOUTH WITH THE WARM
FRONTAL PASSAGE LATE IN THE MORNING...AND FINALLY WEST TO
NORTHWEST LATE IN THE DAY AS THE COLD FRONT TRACKS THROUGH. SPEEDS
INCREASE TOO...ESPECIALLY WITH THE WARM FRONT WHERE MAYBE SOME
GUSTS COULD OCCUR. THERE REMAINS CONCERN FOR LOW LEVEL WIND SHEAR
THIS MORNING BUT RIGHT NOW IT IS TOO MARGINAL TO MENTION.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
544 PM MDT SUN APR 13 2014
.UPDATE...
ISSUED AT 538 PM MDT SUN APR 13 2014
WENT AHEAD AND EXTENDED WINTER HEADLINES FOR THE I-80 CORRIDOR
THROUGH 11 PM THIS EVENING. HAVE ANOTHER BAND OF SNOW MOVING
NORTHEAST OUT OF COLORADO ON IR IMAGERY. MAY NOT LAST THROUGH 11
PM...BUT IT DOES LOOK LIKE ACCUMULATING SNOW WILL CONTINUE AT
LEAST THROUGH MID EVENING BEFORE EASING SOME. SOME MODEL GUIDANCE
SUGGESTING THAT SNOW COULD LAST LONGER. WILL RE-EVALUATE IN A
COUPLE HOURS. DID GO AHEAD AND EXPIRE OUR NORTHERN WINTER
HEADLINES AS RADAR MOSAIC SHOWING SNOW COVERAGE DECREASING.
UPDATES HAVE BEEN SENT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 240 PM MDT SUN APR 13 2014
SATELLITE PIX SHOW WELL-DEFINED CIRCULATION SPINNING THRU UTAH
WITH A JET STREAK BEGINNING TO ROUND ITS BASE. THE RELATIVE LULL
THIS MORNING ACROSS MUCH OF THE AREA WAS A RESULT OF A BREAK
BETWEEN A DEPARTING SHORTWAVE MOVING INTO THE CENTRAL PLAINS AND
THE NEXT ONE OVR UTAH. AT 20Z...THE NEXT LINE OF ENHANCED CLOUD-
TOPS WERE JUST BEGINNING TO ENTER SRN ALBANY AND LARAMIE
COUNTIES...WITH SIMILAR TRENDS NOTICED ON KCYS 88D RETURNS. SO
WILL SEE SNOW RATES PICK UP AGAIN ESPECIALLY ACROSS EXTREME SE
WYOMING THRU AT LEAST SUNSET. AS WAS FEARED...THE HIGH APRIL SUN-
ANGLE HAS RESULTED IN SUBSTANTIAL MELTING ON AREA ROADWAYS...
WHICH HAS LESSENED IMPACT SOME. HOWEVER A FEW ROAD CLOSURES HAVE
OCCURRED ALONG PORTIONS OF INTERSTATE 80. AN ADDITIONAL 1 TO 3
INCHES OF ACCUMULATION CAN BE EXPECTED THRU EARLY THIS EVENING.
SO WILL KEEP THE HIGHLIGHT PACKAGE UNCHANGED FOR NOW AND CONTINUE
TO RE-EVALUATE TRENDS THRU THE REST OF THE AFTERNOON. LATEST
MODELS CONTINUE TO LINGER SNOW INTO THIS EVENING... HOWEVER RATES
SHOULD BE MUCH LESS AS BEST LIFT SHIFTS SOUTH OUT OF THE CWFA.
ANY LINGERING LIGHT SNOW WILL GRADUALLY END THIS EVENING...WITH
DRYING CONDITIONS THEN OVERNIGHT. OTHERWISE...OVERNIGHT LOWS WILL
FALL INTO THE TEENS ACROSS SOUTHEAST WYOMING...WITH LOW 20S OVR
THE PANHANDLE.
HEIGHTS BUILD RAPIDLY BEHIND THE DEPARTING SHORTWAVE ON
MONDAY...YIELDING DRY AND MOSTLY SUNNY CONDITIONS. NORTHWEST
WINDS WILL BE BREEZY ESPECIALLY OVER THE EASTERN PLAINS WHERE
GUSTS OF 25 TO 30 MPH ARE EXPECTED. TEMPERATURES WILL REBOUND
SOME ON MONDAY TOO...ALTHOUGH WILL BE TEMPERED BY TODAYS SNOW.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 240 PM MDT SUN APR 13 2014
TUESDAY...QUICK WARMUP ON TAP AS OUR FLOW ALOFT BECOMES
ZONAL...WEST TO EAST...AHEAD OF THE PROGRESSIVE LOW AMPLITUDE
SHORTWAVE TROUGH ALOFT OVER MONTANA...AIDING THE DEVELOPMENT OF
SURFACE LOW PRESSURE OVER WESTERN SOUTH DAKOTA...AND PRODUCING
DOWNSLOPE KATABATIC WARMING ACROSS OUR COUNTIES WITH MAXIMUM
TEMPERATURES OVER OUR COUNTIES IN THE 50S WEST OF INTERSTATE
25...AND UPPER 50S TO MID 60S ELSEWHERE.
WEDNESDAY...ANOTHER RELATIVELY STRONG CANADIAN ORIGIN COLD
FRONTAL PASSAGE OCCURS EARLY IN THE DAY...WITH TEMPERATURES LIKELY
STEADY OR SLOWLY FALLING DURING THE DAY. THIS SHORTWAVE TROUGH
WILL NOT HAVE AS MUCH MOISTURE AS OUR CURRENT SUNDAY STORM...AND
LESS MESOSCALE AND DYNAMIC LIFT...THUS 30 TO 60 PERCENT POPS AT
LOWER ELEVATIONS WITH 80 TO 100 PERCENT POPS DUE TO FAVORABLE
OROGRAPHICS OVER THE NORTHERN LARAMIE...SNOWY AND SIERRA MADRE
RANGES.
THURSDAY...DRYING OUT PERIOD IN THE WAKE OF THE SHORTWAVE TROUGH
ALOFT WITH A FEW LEFTOVER SHOWERS OVER THE MOUNTAINS. CONTINUED
RELATIVELY COOL WITH SURFACE HIGH PRESSURE KEEPING THE COLD AIR
REINFORCED OVER THE CENTRAL PLAINS STATES.
FRIDAY...SPRINGTIME IN THE ROCKIES CONTINUES WITH A MILD SPRING
DAY TO END OUR TRADITIONAL WORKWEEK...AS TRANSITORY RIDGING ALOFT
MOVES OVER THE ROCKIES...INDUCING STRENGTHENING SURFACE LEE
TROUGHING AND DOWNSLOPE WARMING AIDING HIGH TEMPERATURES SOARING
INTO THE 50S... AND PERHAPS EVEN WARMER IF THE WARMER ECMWF CAN BE
BELIEVED...AS IT SHOWS 1000-500 MB THICKNESSES NEAR 5640 METERS
WITH 700 MB TEMPERATURES NEAR 7 CELSIUS.
SATURDAY...ANOTHER MILD DAY UNDER NORTHWEST FLOW ALOFT AND
RELATIVELY HIGH THICKNESSES AND 700 MB TEMPERATURES.
SUNDAY...EASTER SUNDAY LOOKS MILD AND DRY WITH NORTHWEST FLOW
ALOFT AND A RIDGE ALOFT OVERHEAD...AND EASTER SUNRISE SERVICES
SHOULD BE PLEASANT FOR OUTDOOR ACTIVITIES WITH MINIMAL CLOUD COVER
AND RELATIVELY MILD TEMPERATURES ABOVE FREEZING TO START THE DAY.
.AVIATION...MOUNTAINS OBSCURED. WIDESPREAD IFR AND MVFR THROUGH
THIS AFTERNOON IN SNOW AND LOW CLOUDS...THEN AREAS OF FOG AND LOW
CLOUDS OVERNIGHT PRODUCING IFR AND MVFR...WITH VFR DEVELOPING LATE
TONIGHT AND MONDAY MORNING FROM NORTH TO SOUTH.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY AFTERNOON)
ISSUED AT 538 PM MDT SUN APR 13 2014
LATEST HRRR FORECAST KEEPS KCYS...KLAR AND THE SOUTHERN PANHANDLE
AIRPORTS DOWN THROUGH 06Z AND FOLLOWED THIS GUIDANCE. WITH ANOTHER
BAND OF SNOW MOVING NORTHEAST OUT OF NORTHERN COLORADO...THIS
MAKES SENSE. CONDITIONS SHOULD BEGIN IMPROVING AFTER 06Z WITH
WESTERLY AND NORTHWESTERLY WINDS RETURNING.
&&
.FIRE WEATHER...
ISSUED AT 240 PM MDT SUN APR 13 2014
NO FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK AS FRESH
MOISTURE AND SNOW COVER FROM TODAYS SNOWSTORM LINGERS. SNOW-COVER
WILL ALSO KEEP TEMPERATURES COOLER THROUGH EARLY IN THE
WEEK...WHICH WILL KEEP HUMIDITIES UP. THE NEXT CHANCE OF
PRECIPITATION RETURNS TO THE DISTRICTS ON WEDNESDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 11 PM MDT THIS EVENING FOR WYZ114-116-
117.
WINTER WEATHER ADVISORY UNTIL 11 PM MDT THIS EVENING FOR WYZ108-
110-115-118-119.
NE...NONE.
&&
$$
UPDATE...CLAYCOMB
SHORT TERM...HAHN
LONG TERM...RUBIN
AVIATION...CLAYCOMB
FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
1034 PM PDT SUN APR 13 2014
.UPDATE...
SHORT WAVE PUSHING SOUTH THROUGH THE GREAT BASIN TONIGHT WILL
CREATE ENHANCED EAST-WEST FLOW ACROSS KERN COUNTY LEADING TO GUSTY
WINDS THROUGH THE PASSES AND ALONG THE WEST FACING SLOPES TOWARD
SUNRISE. FINE-TUNED THE FORECAST IN THIS AREA FOR THE NEXT 18
HOURS LEANING ON THE HRRR AND NAM DATA WHICH BETTER SUPPORTED THIS
SCENARIO. ATTM WIND SPEEDS WILL BE BELOW ADVISORY CRITERIA THOUGH
WE/LL MONITOR THROUGH THE NIGHT. THE PERIOD OF STRONGEST WINDS
SHOULD BE RELATIVELY SHORT AND LAST ABOUT 3-5 HOURS. WARM-UP STILL
LOOKS GOOD FOR TOMORROW WITH REGIONAL SOUNDINGS DEPICTING A
DESCENDING AND DESICCATING AIRMASS COMING IN AND MODEL CONSENSUS
REMAINS STEADY.
&&
.SYNOPSIS...
WARM AND DRY TEMPERATURES WILL CONTINUE INTO THE WORK WEEK AS HIGH
PRESSURE PREVAILS OVER THE FORECAST AREA FOR THE NEXT SEVERAL DAYS.
&&
.PREV DISC... /ISSUED 125 PM PDT SUN APR 13 2014/
DISCUSSION...
THE WINDS ALOFT ARE FORECAST TO TURN OFFSHORE OVERNIGHT...AND
SOME DOWNSLOPING THROUGH THE PASSES OF THE KERN COUNTY MOUNTAINS
IS EXPECTED MONDAY. THIS WOULD ERODE THE MARINE AIR OVER THE SOUTH
END OF THE VALLEY AND ALLOW FOR SOME WARMING...EVEN IF THE
REMAINDER OF THE SAN JOAQUIN VALLEY REMAINS COOL.
ABOVE THE MARINE AIR POOL...EXPECT HIGH TEMPERATURES TO BE AS
CURRENTLY FORECAST WITH THE UPPER-LEVEL RIDGE OVER THE REGION.
THE UPPER-LEVEL SHORT-WAVE THAT DROPPED INTO THE GREAT BASIN
OVERNIGHT AND BROUGHT THE GUSTY WINDS TO THE KERN COUNTY MOUNTAINS
AND SOUTHEASTERN KERN DESERT WAS MOVING INTO UTAH AND ARIZONA THIS
AFTERNOON. 500-MB HEIGHTS WILL INCREASE OVER THE NEXT 24 HOURS...
WITH THE 5760-METER HEIGHT LINE AS FAR NORTH AS SACRAMENTO AND RENO.
ANOTHER SHORT-WAVE IS FORECAST TO MOVE INTO THE PACIFIC NORTHWEST
MONDAY NIGHT BUT THE MODELS NO LONGER FORECAST THE WAVE TO WEAKEN
THE RIDGE. RATHER...THE SHORT-WAVE IS FORECAST TO RIDE OVER THE
RIDGE AND DROP INTO THE GREAT BASIN TUESDAY...PUSHING THE RIDGE
OFFSHORE. THE SHORT-WAVE ALSO WILL BRING ANOTHER ROUND OF GUSTY
WINDS TO THE KERN COUNTY MOUNTAINS AND DESERTS TUESDAY AFTERNOON
THROUGH WEDNESDAY MORNING...WITH ADVISORY-LEVEL WINDS POSSIBLE.
THE UPPER-LEVEL RIDGE IS FORECAST TO BUILD BACK INTO THE STATE
THURSDAY...ALTHOUGH BOTH THE GFS AND ECMWF DEVELOP A SPLIT FLOW WITH
THE NORTHERN BRANCH PUSHING INTO THE PACIFIC NORTHWEST AND NORTHERN
CALIFORNIA AND THE SOUTH BRANCH MAINLY INTO NORTHERN MEXICO.
AN UPPER-LEVEL SHORT-WAVE IS FORECAST TO MOVE INTO THE PACIFIC
NORTHWEST THURSDAY NIGHT...FLATTENING THE NORTH BRANCH AND PUSHING
THE SOUTHERN BRANCH FURTHER SOUTHWARD. THE ECMWF IS DEEPER WITH THIS
SHORT-WAVE BUT BOTH MODELS DEVELOP A CLOSED LOW WEST OF SAN DIEGO
WHICH MOVES INTO SOUTHERN CALIFORNIA FRIDAY.
BEYOND FRIDAY THE GFS AND ECMWF CONTINUE THEIR TREND OF DIVERGENT
SOLUTIONS FOR THE WEEKEND FORECAST. CONFIDENCE IN EITHER SOLUTION
REMAINS LOW AT THIS TIME...SO WILL LEAVE THE DAY 6-7 FORECAST
UNCHANGED FOR NOW.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL ACROSS THE CENTRAL CA INTERIOR THROUGH
THE NEXT 24 HOURS.
&&
.AIR QUALITY ISSUES...
NONE.
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS HIGH.
THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED
BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 04-13 97:1898 54:1998 59:1936 34:1911
KFAT 04-14 98:1985 52:1956 60:1985 36:1972
KFAT 04-15 96:1947 57:1988 62:1925 35:1970
KBFL 04-13 94:2008 57:2012 59:1930 32:1893
KBFL 04-14 99:1985 56:2003 62:1962 33:1893
KBFL 04-15 97:1994 57:2007 61:1947 36:1921
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...INIGUEZ
AVN/FW...BSO
SYNOPSIS...WP
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS ALBANY NY
145 AM EDT MON APR 14 2014
.SYNOPSIS...
HIGH PRESSURE OFFSHORE WILL CONTINUE TO USHER IN A SOUTH TO
SOUTHWEST WIND OVER OUR REGION THROUGH MONDAY WITH UNSEASONABLY WARM
TEMPERATURES. A STRONG COLD FRONT WILL SLOWLY CROSS THE REGION
TUESDAY WITH SHOWERS...SOME OF WHICH COULD BE HEAVY...AND BRING A
RETURN TO COLDER WEATHER ON WEDNESDAY. HIGH PRESSURE WILL BUILD IN
THURSDAY THROUGH THE END OF THE WEEK WITH DRY WEATHER EXPECTED.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1245 AM EDT...RADARS INDICATED THAT ALL THE SHOWER ACTIVITY
HAS EXITED OUR ADIRONDACK REGION. THE MESO-SCALE HRRR MODEL
INDICATE NO FURTHER ADDITIONAL SHOWERS ARE EXPECTED. SINCE THERE WAS
NOTHING UPSTREAM...REMOVED ANY MENTION OF SHOWERS FROM THAT AREA.
A WEAK FRONTAL BOUNDARY NEVERTHELESS BROUGHT SOME SHALLOW COOL AIR
DOWN INTO ADIRONDACKS. DURING THE PAST HOUR THE WIND AT BURLINGTON
SHIFTED BACK TO THE SOUTH (WHERE IT HAS BEEN NORTHERLY). WE BELIEVE
THE FRONT HAS RUN OUT OF STEAM AND SHOULD LIFT NORTHWARD...OR AT THE
VERY LEAST...DISSIPATE.
MOST OF THE REGION WILL HAVE A DRY AND MILD NIGHT.
SO FAR...NO REAL SIGN OF STRATUS DEVELOPMENT...ALTHOUGH THE
TEMPERATURE AND DEWPOINTS WERE COMING CLOSE IN VALUE ACROSS LONG
ISLAND. SOME FOG OR STRATUS COULD FORM IN THE NEXT COUPLE OF HOURS.
SO...VERY LITTLE TO TINKER WITH FOR THIS UPDATE. JUST SOME VERY
MINOR RE-TOOLING OF THE GRIDS. WAS TEMPTED TO RAISE OVERNIGHT LOWS
EVEN MORE (THE PREVIOUS SHIFT ALREADY DID THAT). HOWEVER...WE SEE
WHERE SOME SPOTS IN THE MOHAWK VALLEY HAVE DECOUPLE AND COOLED OFF.
EVEN AT ALBANY...THE WIND HAS DIMINISHED (BUT STILL A BREEZE STILL
THERE). WITH A MAINLY CLEAR SKY...TEMPERATURES COULD STILL DROP A
BIT MORE TOWARD DAYBREAK.
EVEN SO...WE ARE LOOKING AT AN INCREDIBLY MILD OVERNIGHT FOR THE
TIME OF YEAR. LOOK FOR LOWS MAINLY IN THE 50S...WITH SOME UPPER 40S
ACROSS THE NORTHERN AREAS...LOCALLY UPPER 50S IN THE CAPITAL REGION.
THIS WOULD MAKE APRIL 14TH THE MILDEST NIGHT IN THE RECORD BOOKS.
THE MILDEST OVERNIGHT LOW IS 55 SET BACK IN 1941. AS LONG AS WE DO
NOT GET THAT LOW AND STAY ABOVE THAT VALUE THROUGH MIDNIGHT
TONIGHT...WE WILL HAVE A NEW RECORD WARM MINIMUM TEMPERATURE FOR
APRIL 14TH.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY/...
ANY LOW CLOUDS IN THE REGION SHOULD MIX OUT THROUGH THE MORNING
DUE TO THE STRONG BOUNDARY LAYER FLOW...BUT SINCE IT IS SOUTHERLY
FLOW...IT MAY TAKE MOST OF THE MORNING TO BREAK UP...WHICH COULD
SHAVE A DEGREE OR TWO OFF THE POTENTIAL HIGH TEMPERATURES TOMORROW
AFTERNOON. BASED ON UPSTREAM CONDITIONS IN THE OH VALLEY...EVEN
WITH QUITE A BIT OF MID AND HIGH CLOUDS AROUND...TEMPERATURES
STILL WELL INTO THE 70S TO NEAR 80...AND SUSPECT MANY AREAS OF
CENTRAL AND EASTERN NY WILL SEE TEMPERATURES MONDAY TO THOSE
LEVELS...WITH A LITTLE COOLER IN HIGHER ELEVATIONS AND PERHAPS NW
CT THROUGH THE BERKSHIRES AND SOUTHERN VT WHERE SOME UPSLOPE
CLOUDS COULD LIMIT THE SUNSHINE A BIT. THERE COULD BE SOME
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS TOMORROW
AFTERNOON...ESPECIALLY IN WESTERN AREAS BUT NO REAL ORGANIZED
FOCUS TO TRIGGER OR SUPPORT MUCH SHOWER OR THUNDERSTORM ACTIVITY.
MONDAY NIGHT AND TUESDAY...INCREASING COVERAGE OF SHOWERS AND
SCATTERED THUNDERSTORMS WITH LOWS MONDAY NIGHT IN THE 50S. THERE
ARE SOME INDICATIONS OF WEAK INSTABILITY ALONG AND AHEAD OF THE
COLD FRONT BUT EVEN WITH CONVECTION ROOTED IN THE BOUNDARY
LAYER...WITH SUCH STRONG BOUNDARY LAYER WINDS OVER THE REGION...
SOME STRONG WIND GUSTS COULD MIX DOWN IN ANY CONVECTION LATE
MONDAY NIGHT AND TUESDAY...EVEN IF THERE MAYBE LITTLE TO NO
THUNDER. LOCALLY HEAVY RAIN SHOULD OCCUR AS WELL SINCE FORCING
SHOULD BE QUITE EXTREME WITH A VERY UNUSUAL EXTREMELY TIGHT
THERMAL GRADIENT ALONG WITH CONSIDERABLY ABOVE NORMAL PRECIPITABLE
WATER ANOMALIES.
TIMING OF THE PASSAGE OF THE COLD FRONT LOOKS TO BE THROUGH THE
DAY TUESDAY...SO AFTER HIGHS IN THE 50S AND 60S...TEMPERATURES
SHOULD FALL THROUGH THE AFTERNOON. THERE IS A DECENT CONSENSUS FOR
PRECIPITATION ENDING AS SNOW SHOWER ACTIVITY TUESDAY NIGHT...
WITH SOME LIGHT ACCUMULATIONS IN HIGHER ELEVATIONS. LOW
TEMPERATURES WEDNESDAY MORNING IN THE 20S TO NEAR 30. DRYING AND
CLEARING TRENDS OCCUR WEDNESDAY WITH HIGHS IN THE 40S TO NEAR
50...SOME 30S SOUTHERN ADIRONDACKS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE LONG TERM PERIOD WILL BE CHARACTERIZED BY SEASONABLE
TEMPERATURES AND MAINLY DRY WEATHER...WITH THE POSSIBILITY OF A
STORM SYSTEM AFFECTING THE REGION FOR THE WEEKEND.
AT THE START OF THE LONG TERM PERIOD...THE EXTENSION OF A HIGH
PRESSURE RIDGE WILL BE IN PLACE ACROSS THE REGION WEDNESDAY
NIGHT...WITH SOUTHWESTERLY LOW-LEVEL RETURN FLOW HELPING TO MODERATE
TEMPERATURES BACK TOWARDS SEASONABLE LEVELS. LOWS WEDNESDAY NIGHT
HOWEVER WILL BE COLD...IN THE LOW 20S TO AROUND 30.
THE INFLUENCE OF THE HIGH PRESSURE RIDGE WILL ALLOW FOR DRY WEATHER
ACROSS THE REGION TO END THE WORK WEEK WITH PARTLY CLOUDY SKIES.
HIGH TEMPERATURES THURSDAY WILL WARM BACK INTO THE UPPER 40S TO MID
50S WITH LOWS THURSDAY NIGHT GENERALLY IN THE UPPER 20S TO MID 30S.
WITH A CONTINUED LOW-LEVEL SOUTHWESTERLY FLOW...HIGHS FRIDAY WILL BE
A LITTLE WARMER THAN THURSDAY...WELL INTO THE 50S AND PERHAPS EVEN
THE LOW 60S IN THE HUDSON RIVER VALLEY DEPENDING ULTIMATELY ON HOW
MUCH DAYTIME BOUNDARY LAYER MIXING OCCURS. LOWS FRIDAY NIGHT WILL BE
IN THE 30S.
LONG RANGE GUIDANCE BEGINS TO DIVERGE BY THE WEEKEND HANDLING THE
EVOLUTION OF A LOW PRESSURE SYSTEM ORIGINATING ACROSS THE CENTRAL
PLAINS. HAVE INTRODUCED CHANCE POPS INTO THE FORECAST FOR MUCH OF
THE WEEKEND FOR A PERIOD OF RAIN SHOWERS. WILL HAVE TO MONITOR
EXACTLY HOW MUCH PRECIPITATION ACCOMPANIES THIS SYSTEM AS THERE ARE
HINTS THAT IT MAY TAP SOME GULF MOISTURE. HIGHS DURING THE WEEKEND
WILL BE IN THE 50S TO LOW 60S WITH LOWS IN THE MID 30S TO LOW 40S.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
MAINLY VFR CONDITIONS WILL CONTINUE AT THE KALB/KGFL/KPOU/KPSF TAF
SITES FOR THE FIRST 18 TO 20 HOURS OF THE TAF PERIOD (15/00Z-02Z)...
WITH MAINLY MID/HIGH CLOUDS OCCURRING DURING THIS PERIOD. MODELS DO
SUGGEST THE POTENTIAL FOR SOME STRATUS TO DEVELOP EARLY MONDAY
MORNING AS THE SOUTHERLY FLOW CONTINUES. HOWEVER...OBSERVATION AND
STLT PICS DO NOT SHOW ANY STRATUS AS OF 0530Z...SO WILL ONLY INCLUDE
THE POSSIBILITY OF MVFR CIGS AND VSBYS AT THE TAF SITES AS A TEMPO
GROUP BETWEEN 14/10Z AND 14/14Z. LATE IN THE PERIOD...AFTER
15/02Z...MVFR AND EVEN IFR STRATUS IS MORE LIKELY TO DEVELOP AT THE
TAF SITES AS THE STRONG SOUTHERLY FLOW CONTINUES AND THE COLD FRONT
MOVES INTO WESTERN NY.
SOUTH WINDS WILL AVERAGE 5-10 KT OVERNIGHT...EXCEPT 10-12 KT AT KALB
AND KPSF WITH GUSTS UP TO 20S KTS. SOUTH WINDS WILL INCREASE BY LATE
MONDAY MORNING INTO THE 12-18 KT RANGE...WITH GUSTS OF 25 TO 30 KTS
AT KALB/KPSF...AND 20 TO 25 KTS AT KGFL/KPOU. THE STRONG WINDS WILL
CONTINUE INTO MONDAY NIGHT AND DIMINISH TO GUSTS OF AROUND 15KTS AT
KGFL/KPOU/KPSF...BUT GUSTS UP TO 25 KTS WILL CONTINUE AT KALB.
OUTLOOK...
LATE MONDAY NIGHT: HIGH OPERATIONAL IMPACT.BREEZY DEFINITE
SHRA...TSRA.
TUESDAY: HIGH OPERATIONAL IMPACT.WINDY WITH GUSTS TO 34.0.
SHRA...TSRA LIKELY.
TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT.BREEZY LIKELY
SHRA...SHSN.
WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
THURSDAY: NO OPERATIONAL IMPACT. NO SIG WX.
THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
SOUTH WINDS 10 TO 20 MPH WITH GUSTS TO 30 MPH TOMORROW...
HIGH PRESSURE OFFSHORE WILL SUPPORT WARM SOUTH TO SOUTHWEST WINDS
OVER OUR REGION THROUGH MONDAY WITH UNSEASONABLY WARM TEMPERATURES.
A STRONG COLD FRONT WILL SLOWLY CROSS THE REGION TUESDAY WITH
SHOWERS...SOME OF WHICH COULD BE HEAVY...AND BRING A RETURN TO
COLDER WEATHER ON WEDNESDAY. HIGH PRESSURE WILL BUILD IN THURSDAY
THROUGH THE END OF THE WEEK WITH DRY WEATHER EXPECTED.
MOST OF THE MOHAWK VALLEY AND CATSKILLS ARE NOW SNOW FREE...WHILE
SNOW COVER STILL LINGERS ACROSS THE NORTHERN BERKSHIRES...LAKE
GEORGE AREA...THE SOUTHERN GREEN MOUNTAINS AND OF COURSE THE
ADIRONDACKS.
A SOUTHERLY BREEZE WILL LIKELY PERSIST TONIGHT IN MANY AREAS...
ESPECIALLY THE CAPITAL REGION...MOHAWK VALLEY AND HIGHER TERRAIN.
THIS WILL PREVENT A FULL RECOVERY.
MONDAY WILL BE A WARM MAINLY DRY DAY WITH PARTIAL SUNSHINE AND THE
CONTINUED SOUTHERLY BREEZE AGAIN AVERAGING 10 TO 20 MPH...BUT
GUSTING UP TO OR EVEN A LITTLE OVER 30 MPH AT TIMES. RH VALUES LOOK
TO BE BOTTOMING OUT IN THE 40 TO 50 PERCENT RANGE.
A SLOW MOVING COLD FRONT SHOULD BRING A SOAKING RAIN TO THE REGION
MONDAY NIGHT AND TUESDAY...FOLLOWED BY MUCH COLDER WEATHER TUESDAY
NIGHT INTO WEDNESDAY.
&&
.HYDROLOGY...
A FLOOD WARNING REMAINS IN EFFECT FOR THE DELTA DAM ON THE UPPER
MOHAWK RIVER UNTIL FURTHER NOTICE...AS RECENT RAINFALL AND
SIGNIFICANT SNOW MELT IS EXPECTED TO KEEP THE RESERVOIR ABOVE
FLOOD STAGE FOR THE NEXT FEW DAYS. A RIVER FLOOD WARNING HAS ALSO
BEEN ISSUED FOR RIVERBANK DUE TO EXPECTED SNOW MELT AND RESULTANT
RIVER RISES INTO THE BEGINNING OF THE WEEK.
OTHER RIVERS IN AND THE ADIRONDACKS...SOUTHERN GREENS...AND
BERKSHIRES WILL SEE MINOR DIURNAL RISES DUE TO SNOW MELT. THE ONLY
AREAS WHERE SIGNIFICANT RIVER ICE REMAINS ARE THE UPPER HUDSON
RIVER AND EAST CANADA CREEK. AT THIS TIME NO SIGNIFICANT ICE JAMS
HAVE BEEN REPORTED...AND FLOODING IS NOT ANTICIPATED AT THIS TIME.
WARM TEMPERATURES THROUGH TUESDAY WILL CAUSE MORE RAPID SNOWMELT
IN THE ADIRONDACKS/LAKE GEORGE AREA AND SOUTHERN VERMONT...
RESULTING IN MORE RUNOFF AND RISES ON RIVERS AND STREAMS.
TEMPERATURES TONIGHT AND MONDAY NIGHT LOOK TO REMAIN WELL ABOVE
FREEZING...SO THE MELT AND RUNOFF WILL CONTINUE UNCHECKED.
THEN...A SLOW MOVING COLD FRONT WILL LIKELY BRING MORE SIGNIFICANT
RAINFALL MONDAY NIGHT INTO TUESDAY. AT THE VERY LEAST...THIS RAIN
ALONG WITH INITIALLY THE WARM TEMPERATURES...WILL LIKELY RESULT IN
SIGNIFICANT WITHIN BANK RISES ON MANY RIVERS AND STREAMS. IN OUR
NORTHERN AREAS...THE COMBINATION OF RAIN AND SNOW MELT COULD EVEN
RESULT IN MINOR TO PERHAPS EVEN SOME MAJOR FLOODING ON SOME
RIVERS AND STREAMS. ONCE THERE IS BETTER AGREEMENT AS TO THE DEGREE
OF SNOW MELT AND RAINFALL AMOUNTS THROUGH TUESDAY...FLOOD WATCHES
MAY NEED TO BE ISSUED MONDAY IF CONFIDENCE IN WIDESPREAD HIGH
IMPACT FLOODING INCREASES. IT IS ADVISABLE TO STAY TUNED FOR
FURTHER UPDATES.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...NAS
NEAR TERM...HWJIV
SHORT TERM...NAS
LONG TERM...IRL
AVIATION...GJM
FIRE WEATHER...NAS
HYDROLOGY...HWJIV/NAS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
406 AM CDT MON APR 14 2014
.DISCUSSION...
330 AM CDT
THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY
IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS.
THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST
CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL
BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD
LEVELS TONIGHT.
THIS MORNING...
THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO
EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES
60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE
DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING
NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND
MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET
SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR
MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS
SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE
BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT
TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE
VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING.
OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD.
THIS AFTERNOON AND TONIGHT...
A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO
THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING
THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL
NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT
500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA.
GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL
BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS
AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE
MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA
AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND
WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST
TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING
THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS
CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE
TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC
EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY
MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY
AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE
DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO
SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH
HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT
FOLLOWS
BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE
SNOW /FOR GOOD FINALLY?/.
ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS
AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING
LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY
SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A
MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE
BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE.
THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE
PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER
MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING
THANKS TO DECENT SNOWFALL RATES AT TIMES.
TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON
AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION
CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS
WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT
/CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE.
TUESDAY THROUGH THURSDAY...
NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A
CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE
850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE
DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO
MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST
AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR
MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES
GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT
ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES
SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN
ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW
AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT
TIME
FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY
WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING
THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY.
FRIDAY AND BEYOND...
GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN
ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST
INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS
GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH
ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING
LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW GIVEN THE
BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM
A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN
TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND
PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW.
GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE
SOMETIME LATE FRIDAY/THIS WEEKEND.
MTF
&&
.CLIMATE...
400 AM CDT
THE FOLLOWING ARE RECORD LOWS FOR THE MORNING OF APRIL 15TH. THE
CHICAGO ONE IS MOST LIKELY IN JEOPARDY.
CHICAGO: 25 (1943)
ROCKFORD: 16 (1928)
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* GUSTY SOUTHERLY WINDS TURNING SHARPLY TO THE NORTH OVERNIGHT
WITH CIGS DROPPING NEAR OR TO IFR.
* OCCASIONAL CHANCES FOR RAIN SHOWERS OVERNIGHT...AND CHANCE FOR
SNOW ACCUMULATIONS DURING THE DAY MONDAY.
BMD
//DISCUSSION...UPDATED 06Z...
LOW PRESSURE LIES NEAR MLI TONIGHT WITH A FRONTAL BOUNDARY EXTENDING
ACROSS FAR NORTHERN ILLINOIS. STRONG SOUTHERLY WINDS ARE OCCURRING
ON THE SOUTH SIDE OF THE FRONT AT THE CHICAGO TERMINALS...BUT AS THE
LOW MOVES EAST OVERNIGHT WINDS WILL TURN SHARPLY TO THE NORTH BEHIND
THE DEPARTING LOW. CIGS WILL DROP TO AROUND 007-010 BEHIND THE FRONT
AND WINDS WILL BECOME QUITE GUSTY...TO AROUND 30 KT OR SO AT TIMES
THROUGH THE MORNING...THEN TAPERING GRADUALLY IN THE AFTERNOON AND
EVENING. ALSO MONDAY AFTERNOON...AN UPPER LEVEL DISTURBANCE MOVING
OVER THE AREA WILL ALLOW PRECIPITATION TO ONCE AGAIN OVERSPREAD THE
TERMINALS. WITH MUCH COLDER AIR IN PLACE TOMORROW...IT DOES APPEAR
MUCH OF THE PRECIP WILL FALL AS SNOW AND CANNOT RULE OUT
ACCUMULATIONS TO AROUND AN INCH. SURFACE TEMPERATURES MAY INITIALLY
MAKE IT DIFFICULT FOR SNOW TO ACCUMULATE...BUT AS SURFACE TEMPS FALL
TO NEAR FREEZING IN THE EVENING CHANCES BECOME A BIT BETTER.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED.
* LOW-MEDIUM CONFIDENCE IN CIGS OVERNIGHT.
* MEDIUM CONFIDENCE IN SNOW TIMING.
BMD
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY THROUGH THURSDAY...PREDOMINANTLY VFR.
FRIDAY...CHANCE OF SHRA.
SATURDAY...VFR PROBABLE.
IZZI
&&
.MARINE...
240 AM CDT
LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS
MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE
BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO
PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH
TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR
THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD
DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL
TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING
WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN
ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 4
PM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
330 AM CDT MON APR 14 2014
.DISCUSSION...
330 AM CDT
THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY
IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS.
THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST
CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL
BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD
LEVELS TONIGHT.
THIS MORNING...
THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO
EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES
60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE
DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING
NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND
MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET
SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR
MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS
SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE
BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT
TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE
VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING.
OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD.
THIS AFTERNOON AND TONIGHT...
A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO
THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING
THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL
NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT
500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA.
GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL
BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS
AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE
MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA
AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND
WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST
TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING
THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS
CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE
TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC
EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY
MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY
AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE
DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO
SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH
HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT FOLLOWS
BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE
SNOW /FOR GOOD FINALLY?/.
ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS
AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING
LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY
SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A
MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE
BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE.
THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE
PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER
MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING
THANKS TO DECENT SNOWFALL RATES AT TIMES.
TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON
AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION
CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS
WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT
/CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE.
TUESDAY THROUGH THURSDAY...
NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A
CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE
850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE
DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO
MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST
AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR
MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES
GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT
ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES
SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN
ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW
AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT TIME
FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY
WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING
THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY.
FRIDAY AND BEYOND...
GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN
ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST
INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS
GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH
ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING
LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW SOME GIVEN THE
BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM A
SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN
TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND
PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW. GRADUALLY
BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE SOMETIME LATE
FRIDAY/THIS WEEKEND.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* GUSTY SOUTHERLY WINDS TURNING SHARPLY TO THE NORTH OVERNIGHT
WITH CIGS DROPPING NEAR OR TO IFR.
* OCCASIONAL CHANCES FOR RAIN SHOWERS OVERNIGHT...AND CHANCE FOR
SNOW ACCUMULATIONS DURING THE DAY MONDAY.
BMD
//DISCUSSION...UPDATED 06Z...
LOW PRESSURE LIES NEAR MLI TONIGHT WITH A FRONTAL BOUNDARY EXTENDING
ACROSS FAR NORTHERN ILLINOIS. STRONG SOUTHERLY WINDS ARE OCCURRING
ON THE SOUTH SIDE OF THE FRONT AT THE CHICAGO TERMINALS...BUT AS THE
LOW MOVES EAST OVERNIGHT WINDS WILL TURN SHARPLY TO THE NORTH BEHIND
THE DEPARTING LOW. CIGS WILL DROP TO AROUND 007-010 BEHIND THE FRONT
AND WINDS WILL BECOME QUITE GUSTY...TO AROUND 30 KT OR SO AT TIMES
THROUGH THE MORNING...THEN TAPERING GRADUALLY IN THE AFTERNOON AND
EVENING. ALSO MONDAY AFTERNOON...AN UPPER LEVEL DISTURBANCE MOVING
OVER THE AREA WILL ALLOW PRECIPITATION TO ONCE AGAIN OVERSPREAD THE
TERMINALS. WITH MUCH COLDER AIR IN PLACE TOMORROW...IT DOES APPEAR
MUCH OF THE PRECIP WILL FALL AS SNOW AND CANNOT RULE OUT
ACCUMULATIONS TO AROUND AN INCH. SURFACE TEMPERATURES MAY INITIALLY
MAKE IT DIFFICULT FOR SNOW TO ACCUMULATE...BUT AS SURFACE TEMPS FALL
TO NEAR FREEZING IN THE EVENING CHANCES BECOME A BIT BETTER.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED.
* LOW-MEDIUM CONFIDENCE IN CIGS OVERNIGHT.
* MEDIUM CONFIDENCE IN SNOW TIMING.
BMD
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY THROUGH THURSDAY...PREDOMINANTLY VFR.
FRIDAY...CHANCE OF SHRA.
SATURDAY...VFR PROBABLE.
IZZI
&&
.MARINE...
240 AM CDT
LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS
MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE
BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO
PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH
TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR
THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD
DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL
TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING
WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN
ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WILMETTE HARBOR TO MICHIGAN CITY IN UNTIL
4 AM MONDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 4
PM MONDAY.
DENSE FOG ADVISORY...NEARSHORE WINTHROP TO WILMETTE HARBORS UNTIL 4 AM MONDAY.
GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
120 AM EDT MON APR 14 2014
.SYNOPSIS...
ISSUED AT 830 PM EDT SUN APR 13 2014
SHOWERS AND SCATTERED THUNDERSTORMS WILL BECOME MORE PREVALENT
TONIGHT AS AN UPPER LEVEL DISTURBANCE APPROACHES THE REGION FROM
THE PLAINS. A COLD FRONT ASSOCIATED WITH THIS SYSTEM WILL TRACK
ACROSS THE REGION ON MONDAY...BRINGING COLDER AND BLUSTERY
CONDITIONS. RAIN WILL TAPER IN COVERAGE DURING THE DAY
MONDAY...BUT ANOTHER DISTURBANCE WILL BRING A CHANCE OF LIGHT SNOW
ACCUMULATIONS FOR MONDAY NIGHT.
&&
.UPDATE...
ISSUED AT 830 PM EDT SUN APR 13 2014
AN AREA OF SHOWERS AND ISOLATED THUNDERSTORMS ASSOCIATED WITH
SMALL SCALE UPPER VORT MAX SHOULD EXIT FAR NORTHWEST PORTIONS OF
THE AREA OVER THE NEXT OVER. LULL IN PRECIP WILL BE RELATIVELY
SHORT LIVED AS STRONGER UPPER LEVEL SHORT WAVE WILL CONTINUE TO TRACK
INTO NORTHWEST INDIANA OVERNIGHT. A LARGE AREA OF ENHANCED LOW
LEVEL MOISTURE TRANSPORT NOTED PER LATEST RAP ANALYSIS ACROSS THE
MID MS RIVER VALLEY WILL SHIFT EASTWARD AND EXTEND FROM THE LOWER
OHIO VALLEY INTO THE SOUTHERN GREAT LAKES BY 09Z. A LARGE AREA OF
RAIN/EMBEDDED THUNDERSTORMS COINCIDING WITH THIS STRONGER LOW
LEVEL MOISTURE TRANSPORT ACROSS SOUTHEAST MISSOURI WILL CONTINUE
TO EXPAND NORTHEASTWARD OVERNIGHT...BRINGING WIDESPREAD
RAIN/EMBEDDED THUNDER TO MOST OF THE FORECAST AREA THROUGH EARLY
MONDAY MORNING. NORTHWARD ADVECTION OF 1.25-1.40 INCH PWAT AXIS
INTO THE AREA OVERNIGHT AND STRENGTHENING LOW LEVEL FRONTAL
CIRCULATION SHOULD PROMOTE SOME HEALTHY RAINFALL AMOUNTS POSSIBLY
APPROACHING AROUND AN INCH ACROSS WESTERN PORTIONS OF THE AREA
WHICH COULD LEAD TO SOME MINOR FLOODING CONCERNS GIVEN RECENT WET
PERIOD/MOIST SOILS. MAIN TWEAKS TO FORECAST THIS EVENING WERE TO
SLIGHTLY INCREASE POPS OVERNIGHT IN ASSOCIATION WITH ABOVE
MENTIONED TRENDS...ALONG WITH SLIGHT ADJUSTMENT TO HOURLY TEMP
CURVE ACROSS THE NORTHWEST COOLER TEMPS RESIDE INITIALLY DUE TO
EARLIER MARINE INFLUENCE. BEST CHANCE OF THUNDER APPEARS TO BE
DURING THE OVERNIGHT HOURS...WHERE SLIGHT ENHANCEMENT TO WEAK
ELEVATED INSTABILITY IS EXPECTED IN ASSOCIATION WITH LOW LEVEL
MOIST TONGUE.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 328 PM EDT SUN APR 13 2014
VIGOROUS LOW PRESSURE OVR KS THIS AFTN WILL LIFT QUICKLY NEWD INTO
THE MI THUMB BY DAYBREAK TOMORROW AND PROPEL A STG CDFNT EWD ACRS
THE AREA. SO FAR WARM SECTOR HAS BEEN A DUD WITH THIS SYS OWING TO
POOR MSTR RTN UNDERNEATH STEEP EML AND SEE LTL EVIDENCE THAT WILL
CHANGE INTO EARLY EVE.
BETTER PROSPECTS FOR RAINFALL XPCD LT TONIGHT AHD AND ALG SFC FNTL
BNDRY. HWVR WKNG CAP WITHIN ZONE OF FVRBL THETA-E AND SUSTAINED LL
WAA STILL WARRANTS HOLDING ONTO SOME POPS NW THIRD THROUGH EVENING.
OTRWS STG POST FNTL CAA WEDGE FOLLOWS MON AM W/CRASHING SFC TEMPS.
LINGERING POST FNTL SHRA XPCD IN THE MORNING FOLLOWED BY LARGELY DRY
CONDS IN THE AFTN ASSOCD/W MID LVL DRY SLOT OF EXITING SYS ALOFT.
&&
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 328 PM EDT SUN APR 13 2014
FOCUS OF FORECAST WILL BE ON ARRIVAL OF UNSEASONABLY COLD AIR AND
ACCUMULATING SNOWFALL AT THE START OF THE PERIOD.
COLD FRONT SHOULD BE LONG GONE BY MONDAY EVENING WITH THE REGION IN
A VERY BRIEF LULL IN PRECIP TO START THINGS OUT. THIS WILL QUICKLY
CHANGE AS A DISTURBANCE MOVES ALONG THE FRONT AND BRINGS ANOTHER
QUICK SHOT OF INCREASED MSTR AND LIFT. MODELS DO VARY ON EXACTLY HOW
MUCH QPF BUT IN GENERAL PAINT THE NEED FOR LIKELY TO CAT POPS FOR
MOST AREAS FOR A PERIOD...MAINLY IN THE 3Z TO 9Z TUES TIME FRAME.
HAVE BROKE GRIDS INTO 3 HOUR BLOCKS TO TRY TO ADD SOME DETAIL IN
TERMS OF TIMING. GIVEN RATHER PRONOUNCED/FAST ARRIVING PUNCH OF COLD
AIR...MIX POTENTIAL FOR PRECIP LOOKING MORE LIMITED WITH 1000-850 MB
THICKNESS AND SFC TEMPS ALL POINTING TOWARDS ALL SNOW. THE BIGGEST
CHALLENGE LIE WITH HOW MUCH PRECIP FALLS AND POTENTIAL
ACCUMULATIONS. IMPRESSIVE 850 MB DROP FOR MID APRIL WITH VALUES FROM
-8 TO - 10 C DURING BEST PRECIP WINDOW. AT THIS TIME...THINK MANY
AREAS WILL SEE SOME WET SNOWFLAKES TO START THINGS OFF IN THE
EVENING...WITH THIS SNOW BEING LESS WET WITH TIME AS COLDER AIR
SETTLES IN AND SNOW RATIOS INCREASE SOMEWHAT. IF WE WERE STILL
ENTRENCHED IN THE GENERALLY COLD PATTERN...WE MIGHT BE LOOKING AT
SEVERAL INCHES OF SNOW STICKING AROUND AND CAUSING A LOT OF
PROBLEMS. HOWEVER...DESPITE THE COLD AIR ARRIVING...ROAD/GROUND
TEMPS HAVE WARMED SUBSTANTIALLY GIVEN THE 70S OF THE PAST COUPLE OF
DAYS. THIS WILL LIKELY ALLOW FOR MELTING OF A LOT OF THE
SNOWFALL...ESPECIALLY ON ROADS. HOWEVER...IF SNOW CAN COME DOWN HARD
ENOUGH IT MAY BE ABLE TO ACCUMULATE AND STICK AROUND BRIEFLY INTO
PARTS OF TUESDAY AS HIGHS STRUGGLE THROUGH THE 30S TO NEAR 40. GRIDS
REFLECT ACCUMULATIONS OF 1 TO 3 INCHES WITH HIGHEST AMOUNTS IN SE
AREAS WHERE MSTR WILL LINGER LONGER. AGAIN...IT NEEDS TO BE STRESSED
THAT MUCH OF THIS SNOW MAY NOT ACCUMULATE IN THE EVENING BUT
OVERNIGHT...ROADS COULD BECOME SLIPPERY IN SOME AREAS AS OVERNIGHT
LOWS PLUMMET THROUGH THE 20S. FORECAST WILL NEED FINE TUNING FURTHER
OVER THE NEXT 12 TO 24 HOURS.
ONCE THIS SYSTEM PASSES BY...DRIER WEATHER WILL SETTLE IN UNTIL
THURS NGT BEFORE THE NEXT SYSTEM BEGINS TO APPROACH THE REGION WITH
CHANCES FOR SHOWERS. TEMPS WILL CLIMB BACK INTO THE 50S AND POSSIBLY
60S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 120 AM EDT MON APR 14 2014
LEAD SHORTWAVE AND ATTENDANT SFC WAVE WILL LIFT NORTHEAST THROUGH
THE GREAT LAKES REGION THIS MORNING...FINALLY FORCING A STRONG
FRONTAL BOUNDARY EAST THROUGH SBN AROUND 12/13Z AND FWA 15/16Z.
SHOWERS/ISO THUNDER AND DETERIORATING FLIGHT CONDITIONS EXPECTED
AHEAD AND ALONG THIS FRONT IN IMPRESSIVE MOISTURE CHANNEL/50-60 KT
LLJ. PERIOD OF IFR CONDITIONS REMAIN POSSIBLE ALONG
BOUNDARY...WITH IFR TO MID RANGE MVFR CIGS AND GUSTY NORTHWESTERLY
WINDS ANTICIPATED IN STRONG POST FRONTAL CAA WEDGE LATE THIS
MORNING/AFTERNOON. CANNOT RULE OUT A FEW SHOWERS THIS AFTERNOON
AS MID LEVEL BAROCLINIC ZONE LINGERS OVER NORTHERN INDIANA IN
ADVANCE OF A CONSOLIDATING/AMPLIFYING CENTRAL CONUS UPPER TROUGH.
RENEWED MID LEVEL FGEN/DEFORMATION WITH THIS UPPER TROUGH SHOULD
ALLOW ANOTHER ROUND OF MORE WIDESPREAD PCPN TO OVERSPREAD NORTHERN
INDIANA THIS EVENING INTO THE OVERNIGHT. MODEL THERMAL PROFILES
ACTUALLY FAVOR MAINLY SNOW IN SBN...WITH A RAIN/SNOW MIX CHANGING
OVER TO ALL SNOW IN FWA LATE IN THE EVENING/EARLY OVERNIGHT.
&&
.MARINE...
ISSUED AT 328 PM EDT SUN APR 13 2014
AREAS OF FOG BEING INTRODUCED TO NEARSHORE WATERS WITH WEB CAMS
SHOWING FOG OFFSHORE...MORE THAN LIKELY MORE IN THE 3 TO 5 NM
RANGE. TRENDS WILL BE MONITORED FOR NEED FOR MARINE DENSE FOG
ADVISORY BUT MAIN THREAT SHOULD REMAIN IN OPEN WATERS.
WILL ALSO HOIST SMALL CRAFT ADVISORY STARTING LATER TONIGHT AND
CONTINUING THROUGH AT LEAST MONDAY IF NOT INTO TUESDAY. POTENTIAL
FOR A PERIOD OF GALE FORCE GUSTS BUT HAVE KEPT WORDING TONED DOWN
FOR THE TIME BEING WITH A FEW GUSTS TO 35 KTS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 AM EDT THIS MORNING FOR LMZ043-046.
GALE WARNING FROM 7 AM THIS MORNING TO 5 PM EDT THIS AFTERNOON
FOR LMZ043-046.
&&
$$
UPDATE...MARSILI
SYNOPSIS...MARSILI
SHORT TERM...T
LONG TERM...FISHER
AVIATION...STEINWEDEL
MARINE...FISHER
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1138 PM MDT SUN APR 13 2014
.UPDATE...
ISSUED AT 1129 PM MDT SUN APR 13 2014
SNOWFALL IS DECREASING IN INTENSITY AND COVERAGE. DO NOT EXPECT
MUCH MORE ACCUMULATION. SO WENT AHEAD AND CANCELLED THE WINTER
WEATHER ADVISORY.
UPDATE ISSUED AT 901 PM MDT SUN APR 13 2014
NEWER MODEL DATA IS CONFIRMING WHAT RECENT OBSERVATION AND RADAR
TRENDS HAVE SHOWING WITH THE DECREASING TREND OF THE SNOW. HAVE
CANCELLED THE WINTER WEATHER ADVISORY FOR RED WILLOW...DECATUR AND
NORTON COUNTIES.
UPDATE ISSUED AT 803 PM MDT SUN APR 13 2014
HAVE RECENTLY COMPLETED A COUPLE OF UPDATES. HAVE ALLOWED THE WIND
ADVISORY TO EXPIRE WITH WINDS BELOW CRITERIA. REST OF FORECAST
LOOKING ON TRACK. HAVE ADJUSTED WEATHER AND POPS TO REFLECT THE
TRENDS SEEN ON OBSERVATIONS...SATELLITE AND RADAR. WINTER WEATHER
ADVISORY DOING FINE WITH EXPECTED LIFT TO CONTINUE THROUGH MIDNIGHT.
EASTERN END OF THE ADVISORY MAY NOT GET TOO MUCH MORE SNOW BUT WILL
KEEP IT WITH THE EXPECTED INTENSITY OF SNOW COMBINED WITH WHAT HAS
ALREADY AND THE WINDY CONDITIONS.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 203 PM MDT SUN APR 13 2014
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW LARGE UPPER LEVEL
TROUGH ACROSS NORTHERN/CENTRAL US WITH TWO DISTINCT H5/H7
CIRCULATIONS OVER THE PLAINS AND CENTRAL ROCKIES. THE FIRST
CIRCULATION IS ASSOCIATED THE H5/H7 LOW NO OVER CENTRAL/EASTERN
NEBRASKA...RESPONSIBLE FOR DEFORMATION BAND OF SNOW THAT FORMED
OVER NORTHEAST COLORADO EARLY THIS MORNING AND IS NOW OVER THE
NORTHERN PART OF OUR CWA. THE SECOND CIRCULATION IS ASSOCIATE
WITH A SECOND CLOSED H7 LOW AND H5 TROUGH DEEPENING OVER WESTERN
COLORADO.
REGARDING WIND ADVISORY THIS AFTERNOON/EVENING...WINDS HAVE
STRUGGLED TO APPROACH CRITERIA THOUGH THEY HAVE BEEN NEAR ADVISORY
CRITERIA AT TIMES. THE PLAN IS TO HOLD ONTO THE ONGOING WIND
ADVISORY FOR A FEW MORE HOURS AS THE BEST PRESSURE RISES ARE
BEGINNING TO SHIFT TO THE SOUTH AND EAST...AND PROBABLY CANCEL THE
ADVISORY BEFORE 00Z.
REGARDING WINTER WEATHER ADVISORY...AS MENTIONED IN THE SYNOPSIS
THERE ARE TWO DISTINCT UPPER LEVEL CIRCULATIONS RESPONSIBLE FOR
BRINGING WINTRY WEATHER TO OUR CWA TODAY/TONIGHT. THE DEFORMATION
BAND ASSOCIATED WITH THE CIRCULATION OVER NEBRASKA SHOULD CONTINUE
TO TRANSITION NORTH AND EAST...WITH MAIN IMPACT OVER THE NORTHERN
PART OF THE CWA WINDING DOWN AROUND 00Z. I COULD SEE US CANCELING
THE NORTHERN PART OF THE ADVISORY EARLY (00Z-03Z) AS WE WILL LIKELY
NOT SEE ADVISORY CRITERIA MET UP NORTH WITH THE 2ND UPPER LOW. THE
SOUTHERN PART OF THE ADVISORY (KIT CARSON/CHEYENNE CO) HAVE
AVOIDED THE BRUNT OF THIS FIRST WAVE...HOWEVER THE SECOND
CIRCULATION WILL BEGIN TO BRING LIGHT TO MODERATE SNOW INTO
EASTERN COLORADO THIS EVENING AND THIS IS WHEN THESE LOCATIONS
MAY SEE THE GREATEST IMPACT. CONFIDENCE IS ACTUALLY HIGHER FOR KIT
CARSON/CHEYENNE CO TO MEET ADVISORY CRITERIA THIS EVENING THAN
SHERMAN. SHERMAN/WALLACE/GREELEY COULD BE CLOSE BASED ON LATEST
MODEL OUTPUT...HOWEVER CONFIDENCE IS TOO LOW TO ADD
WALLACE/GREELEY...OR CANCEL SHERMAN AT THIS POINT. WE WILL NEED TO
MONITOR NEAR TERM TRENDS. PRECIP SHOULD QUICKLY WIND DOWN THIS
EVENING IN THE NORTH AND THEN AFTER MIDNIGHT ACROSS THE
SOUTH...WITH MAYBE SNOW LINGERING THROUGH MID MORNING MONDAY IN
THE FAR SOUTH.
REGARDING ANTICIPATED IMPACTS THIS AFTERNOON/EVENING...ADDITIONAL
LIGHT SNOW ACCUMULATIONS ARE ANTICIPATED FOR MOST
LOCATIONS...HOWEVER MODERATE-HEAVY ACCUMULATIONS ARE MOST LIKELY
THIS EVENING OVER KIT CARSON/CHEYENNE COLORADO COUNTIES. WINDY
CONDITIONS WILL CONTINUE...AND WILL CONTINUE BRING BLOWING SNOW
CHANCES AND LOCALLY REDUCED VISIBILITIES THROUGH AROUND 03Z.
LATE TONIGHT/MONDAY TEMPS...HARD FREEZE IS LIKELY WITH SUB
FREEZING TEMPS ALREADY ACROSS MOST OF THE CWA...AND UPSTREAM TEMPS
IN THE 23-25F ALREADY BEING REPORTED. TOO EARLY IN THE SEASON TO
ISSUE FROST/FREEZE HIGHLIGHTS CONSIDERING CLIMATE NORMS FOR LAST
FROST/FREEZE. AIR MASS WILL BEGIN TO MODERATE SOME MONDAY...HOWEVER
HIGHS WILL REMAIN WELL BELOW NORMAL WITH VALUES IN THE 40S ACROSS
THE CWA.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 210 PM MDT SUN APR 13 2014
A SHORT WAVE RIDGE MOVES OVER THE ROCKIES AND FLATTENS AS IT MOVES
ACROSS THE HIGH PLAINS BETWEEN MONDAY NIGHT THROUGH TUESDAY
NIGHT. TEMPERATES WILL WARM AND CONDITIONS WILL DRY DURING THAT
TIME. BETWEEN LATE WEDNESDAY THROUGH THURSDAY NIGHT ANOTHER LOW
PRESSURE SYSTEM WILL MOVE THROUGH THE ROCKIES AND HIGH PLAINS
REGIONS...BRINGING ANOTHER ROUND OF COOLER TEMPERATURES AND A
CHANCE OF PRECIPITATION TO THE CENTRAL HIGH PLAINS. A MIXTURE OF
RAIN AND SNOW IS EXPECTED WITH THIS SYSTEM.
MODEL SOLUTIONS BECOME MORE DIVERGENT BETWEEN FRIDAY AND
SUNDAY...BUT THE CONSENSUS IS CONDITIONS WILL BE DRY AND WARMER
WITH TEMPERATURES NEAR AVERAGE FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1129 PM MDT SUN APR 13 2014
VFR CONDITIONS HAVE BEGUN AT KMCK AND WILL SOON FOLLOW AT KGLD.
VFR CONDITIONS WILL THEN CONTINUE FOR THE REST OF THE PERIOD.
THERE WILL BE A BRIEF REPRIEVE IN THE GUSTY WINDS LATER ON TONIGHT
BEFORE INCREASING AND BECOMING GUSTY AROUND MID MORNING. THESE
WINDS WILL CONTINUE UNTIL NEAR SUNSET.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1145 PM CDT Sun Apr 13 2014
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Monday)
Issued at 326 PM CDT SUN APR 13 2014
20Z water vapor imagery shows a shortwave lifting across eastern
KS as another wave digs south towards the four corners region.
This initial wave has sparked a line of thunderstorms to form
along a cold front that is surging southeast through the forecast
area. Much of the short range guidance is pointing towards the
convection to be east of the forecast area by 7 pm, which fits in
with current radar trends. Therefore have lowered pops for this
evening and removed mention of thunder. There is a band of snow
across NEB. The HRRR and RAP suggest the tail end of this precip
may move east along the NEB state line through the evening as the
first shortwave lifts northeast. Precip accumulations with this
should be fairly light as the better mid level frontogenesis stays
mainly to the north. However as the second shortwave comes out of
the Rockies late tonight and through the morning Monday, this
frontogenetical band redevelops south and most guidance is
pointing at a band of snow moving over east central KS. The
frontogenesis looks strong enough for a decent band of snow and
possible accumulations around an inch through late morning Monday.
This will be highly dependent on the intensity of the snowfall
however since ground temps remain relatively warm. If the band
produces higher snowfall rates, some parts of east central KS
could see accumulations a little higher.
In between the convection this afternoon and the frontogenetical
precip overnight, think there will be a lull in the precip and
have tapered pops down this evening. Models show saturation in the
lower levels hinting at the possibility for some drizzle which
could be freezing depending on surface temps. However the
conditions for drizzle do not look to persist for long as some mid
level drying occurs before the next shortwave moves in and
saturates the column. Overall am not to excited about the
prospects for drizzle but can`t rule out the chance so will
include a mention in the forecast.
Lows tonight should fall into the lower 30s due to strong cold air
advection behind the front. Temps in central NEB have already
fallen into the upper 20s suggesting my lows may not be cool
enough. In any case, freezing temps look likely tonight and will
issue as freeze warning as we have entered the locally defined
growing season. Cold air advection persists through the morning
Monday so highs are not expected to warm much. However think
clouds will eventually clear out by the afternoon so some
insolation may help to warm highs into the 40s.
.LONG TERM...(Monday Night through Sunday)
Issued at 326 PM CDT SUN APR 13 2014
Monday night through Wednesday looks dry as the central plains see
dry northwest flow develop ahead of the next wave expected to dig
into the plains by Thursday. The medium range models seem to be in
some agreement with timing of the next wave therefore have trended
pops up for Thursday and Thursday night. There does not appear to
be much instability with this system as warm moist are is slow to
return. However there does appear to be another shot of cold air
moving in Thursday night which could cause a brief change over to
snow before the precip comes to an end. Therefore have maintained
a mention of rain and snow for Thursday night.
While less certain, there are indications of a southern stream
wave trying to phase with a northern stream wave over the area
Sunday. Confidence is low since the GFS struggles to advect
moisture this far north. However with the ECMWF breaking out some
QPF, will insert some low (20-30%) POPs Saturday night and Sunday.
A hard freeze looks likely Tuesday morning as skies clear out and
surface ridging moves over the region. Therefore have continued
with lows in the lower to middle 20s and will post a freeze
warning through Tuesday morning too. Southerly flow returns for
Wednesday helping to moderate the cool temps before the next cold
front moves in Thursday and knocks temps back down into the 40s
and 50s for Thursday and Friday. With a split flow for the weekend
and the northern stream remaining north, temps should moderate
into the 60s for the weekend.
&&
.AVIATION...(For the 06Z TAFs through 06Z Monday Night)
Issued at 1132 PM CDT SUN APR 13 2014
MVFR conditions should persist through for the remainder of
tonight. A band of snow will develop over south central KS early
tomorrow morning and move northeast towards the taf sites. MHK may
be on the northern edge of the axis of snow therefore have
shortened the period of snow there. There could be a brief period
of moderate to heavy snow that would cause IFR vis but confidence
for that occurring is low at this point. Conditions should improve
to VFR after the snow band exits the taf sites.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING until 10 AM CDT Monday FOR KSZ008>012-020>024-026-
034>040-054>056-058-059.
FREEZE WARNING from 11 PM Monday to 9 AM CDT Tuesday FOR
KSZ008>012-020>024-026-034>040-054>056-058-059.
&&
$$
SHORT TERM...Wolters
LONG TERM...Wolters
AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS JACKSON KY
449 AM EDT MON APR 14 2014
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT MON APR 14 2014
THERE ARE SEVERAL FEATURES OF INTEREST THIS MORNING UPSTREAM. A WEAK
MID LEVEL TROUGH IS NOW MOVING INTO THE NORTHERN OHIO RIVER VALLEY
WITH A SURFACE LOW PUSHING INTO THE GREAT LAKES REGION. THIS INITIAL
TROUGH HAD BEEN RESPONSIBLE FOR AN ORGANIZED AREA OF SHOWERS AND
STORMS AS IT PUSHED INTO WESTERN KENTUCKY OVERNIGHT. AS THIS
ACTIVITY CONTINUES TO PUSH EAST THIS MORNING IT WILL ENCOUNTER A MUCH
MORE STABLE AND DRY AIR MASS AND WILL QUICKLY WEAKEN. HRRR HAS A GOOD
HANDLE ON THIS AREA OF PRECIPITATION. AS IT REACHES EASTERN
KENTUCKY...IT LOOKS LIKE THE ACTIVITY MAY BECOME MORE SCATTERED AND
EVEN MORE SO AS IT PUSHES FURTHER EAST. WHILE A FASTER ONSET OF
PRECIPITATION LOOKS LIKELY TODAY...IT ALSO LOOKS LIKE ONLY A LIMITED
WINDOW FOR PRECIPITATION THROUGH EARLY AFTERNOON BEFORE WE DRY OUT
AGAIN BY LATE AFTERNOON AND THIS EVENING AS SUBSIDENCE SPREADS BACK
OVER THE AREA AHEAD OF THE NEXT TROUGH. THUS...GOING TO BACK OFF POPS
TO MORE SCATTERED COVERAGE TODAY AS MANY AREAS...ESPECIALLY IN THE
EAST MAY NOT MEASURE TODAY OR WILL LIKELY SEE VERY LIGHT RAINFALL.
WINDS ARE THE OTHER CONCERN FOR TODAY AS WINDS ARE ALREADY GUSTING UP
TO 30 MPH THIS MORNING. WITH THE WEAKENING SHOWERS SPREADING INTO THE
AREA...WE MAY TAP INTO SOME HIGHER WINDS ALOFT WITH 40 KNOTS AROUND
900 MB. THIS MAY CREATE SOME VERY GUSTY CONDITIONS AS THIS BAND OF
SHOWERS MOVES EAST THROUGH EARLY AFTERNOON. THUS...WENT AHEAD AND
ISSUED A LAKE WIND ADVISORY THROUGH 23Z TODAY TO ACCOUNT FOR THESE
WINDS.
MEANWHILE...A SHARPER MID LEVEL TROUGH IS CONTINUING TO DIG OVER THE
CENTRAL ROCKIES WITH A NORTHERN STREAM WAVE PUSHING INTO THE NORTHERN
PLAINS. AS THESE TWO SYSTEMS PHASE AND MOVE EAST...IT WILL ACCELERATE
THE COLD FRONT ACROSS EASTERN KENTUCKY LATE TONIGHT. WITH GOOD
DYNAMICS IN PLACE...AND GOOD CONVERGENCE ALONG THE SURFACE
BOUNDARY...WE WILL SEE WIDESPREAD PRECIPITATION DEVELOP AS THIS
BOUNDARY MOVES EAST. A NARROW RIBBON OF INSTABILITY JUST AHEAD OF THE
FRONT COULD LEND ITSELF TO SOME LIGHTNING OVERNIGHT.
HOWEVER...INSTABILITY SHOULD REMAIN ELEVATED...AND POSE NO SEVERE
THREAT. THE BIGGER STORY WILL BE THE RETURN OF MUCH COLDER AIR INTO
EASTERN KENTUCKY FOR TUESDAY. IT DOES APPEAR SOME MOISTURE WILL
LINGER BEHIND THE COLD FRONT YIELDING AN A BRIEF OPPORTUNITY FOR SOME
SNOW TO MIX IN JUST BEFORE PRECIPITATION ENDS. MOST LOCATIONS WILL
ESCAPE ANY SNOW ACCUMULATION AS THE GROUND WILL SIMPLY BE TOO WARM.
THE EXCEPTION WILL BE IN THE HIGHEST TERRAIN ABOVE 2.5KFT AS COLDER
SURFACE TEMPERATURES MAY ALLOW FOR BETTER ACCUMULATION POTENTIAL.
WILL GO WITH UP TO 2 INCHES ON THE HIGHEST PEAKS IN SOUTHEAST
KENTUCKY. PRECIPITATION WILL COME TO AN END THROUGH THE DAY
TUESDAY...BUT SOME DRIZZLE OR FLURRIES COULD LINGER ACROSS THE HIGH
TERRAIN IN THE SOUTHEAST INTO THE AFTERNOON OR EVENING HOURS. HIGHS
WILL STRUGGLE TO REACH 40 ON TUESDAY...WITH HIGHS POSSIBLY OCCURRING
EARLY IN THE DAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 449 AM EDT MON APR 14 2014
A SURFACE RIDGE WILL BE MOVING OVER THE AREA WITH AN UNSEASONABLY
COLD AND DRY AIR MASS AT THE START OF THE PERIOD. MODELS HAVE BEEN
CONSISTENT IN THEIR SOLUTIONS...AGREEING ON CLEARING SKIES AND EASING
WINDS LEADING TO A HARD FREEZE FOR MOST LOCATIONS...AND A FREEZE
WATCH HAS BEEN ISSUED FOR TUESDAY NIGHT INTO WEDNESDAY MORNING. THE
HIGH WILL SLIP TO OUR EAST WEDNESDAY AND THURSDAY...AND WEAK WARM AIR
ADVECTION WILL RETURN. MOISTURE WILL BE SLOW TO INCREASE...SO EVEN
THOUGH AFTERNOONS WILL BE MILDER...CLEAR TO PARTLY CLOUDY SKIES WILL
ALLOW FOR A LARGE DIURNAL RANGE WITH CHILLY EARLY MORNINGS. FROST
WILL BE EXPECTED FOR MANY LOCATIONS ON WEDNESDAY NIGHT...AND POSSIBLY
ON THURDAY NIGHT IN THE COLDEST VALLEYS.
FROM FRIDAY THROUGH THE WEEKEND THE MODELS BECOME MORE DISPARATE AS
TIME GOES BY. IN GENERAL TERMS...ANOTHER MID/UPPER LEVEL TROUGH WILL
PROGRESS EAST ACROSS THE CONUS. COMPARED TO THE GFS...THE ECMWF IS
STRONGER WITH THE SOUTHERN END OF THIS FEATURE NEAR THE GULF COAST.
MEANWHILE...THE GFS IS WEAKER NEAR THE GULF COAST...BUT MUCH MORE
AMPLIFIED ACROSS THE NORTH CENTRAL CONUS. THIS AFFECTS CORRESPONDING
SURFACE LOW DEVELOPMENT. BOTH SCENARIOS BRING THE GREATEST POP ON
FRIDAY NIGHT...BUT THE GFS IS MORE SUPPORTIVE OF PRECIP. THE
DIFFERING SURFACE PATTERNS ALSO AFFECT HOW MUCH COLDER FLOWS
SOUTHWARD DURING THE WEEKEND. SOME MEMBERS OF THE GFS ENSEMBLE VARY
QUITE A BIT FROM THE OPERATIONAL RUN...AND LEND SUPPORT TO THE ECMWF
PATTERN...BUT THE GFS ENSEMBLE MEAN SUPPORTS THE OPERATIONAL GFS.
WITH ALL THIS IN MIND...WILL CONTINUE TO USE A GENERALIZED MODEL
COMPROMISE...WITH A LOWER CONFIDENCE THAN NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 232 AM EDT MON APR 14 2014
VFR CONDITIONS WILL LIKELY PERSIST THROUGH THE TAF FORECAST PERIOD.
THE MAIN AVIATION CONCERN WILL BE THE POSSIBILITY OF SOME LOW LEVEL
WIND SHEAR THROUGH THE REMAINDER OF THE OVERNIGHT HOURS. THEN WINDS
WILL RAMP UP BY MORNING WITH GUSTY SOUTH WINDS ANTICIPATED AND THESE
GUSTS COULD REACH AROUND 30 KNOTS AT TIMES THROUGH THE DAY. A FEW
ISOLATED HIGHER WIND GUSTS COULD ALSO BE POSSIBLE IN AND AROUND
SHOWERS WHICH WILL BE ARRIVING AROUND DAYBREAK IN THE WEST. A SHARP
WIND SHIFT IS ANTICIPATED TONIGHT AS A COLD FRONT PUSHES ACROSS
EASTERN KENTUCKY. THIS WIND SHIFT WILL LIKELY OCCUR CLOSER TO
MIDNIGHT OR LATER AS WINDS GO FROM THE SOUTH TO THE WEST AND
NORTHWEST. IN ADDITION...WIDESPREAD PRECIPITATION WILL OVERSPREAD THE
AREA LATE TONIGHT WITH CIGS COMING DOWN LATE TONIGHT TO MVFR OR
LOWER.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY MORNING FOR
KYZ044-050>052-058>060-068-069-079-080-083>088-104-106>120.
LAKE WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR KYZ044-
050>052-058>060-068-069-079-080-083>088-104-106>120.
&&
$$
SHORT TERM...KAS
LONG TERM...HAL
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
328 AM EDT MON APR 14 2014
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT MON APR 14 2014
THERE ARE SEVERAL FEATURES OF INTEREST THIS MORNING UPSTREAM. A WEAK
MID LEVEL TROUGH IS NOW MOVING INTO THE NORTHERN OHIO RIVER VALLEY
WITH A SURFACE LOW PUSHING INTO THE GREAT LAKES REGION. THIS INITIAL
TROUGH HAD BEEN RESPONSIBLE FOR AN ORGANIZED AREA OF SHOWERS AND
STORMS AS IT PUSHING INTO WESTERN KENTUCKY OVERNIGHT. AS THIS
ACTIVITY CONTINUES TO PUSH EAST THIS MORNING IT WILL ENCOUNTER A MUCH
MORE STABLE AND DRY AIRMASS AND WILL QUICKLY WEAKEN. HRRR HAS A GOOD
HANDLE ON THIS AREA OF PRECIPITATION. AS IT REACHES EASTERN
KENTUCKY...IT LOOKS LIKE THE ACTIVITY MAY BECOME MORE SCATTERED AND
EVEN MORE SO AS IT PUSHES FURTHER EAST. WHILE A FASTER ONSET OF
PRECIPITATION LOOKS LIKELY TODAY...IT ALSO LOOKS LIKE ONLY A LIMITED
WINDOW FOR PRECIPITATION THROUGH EARLY AFTERNOON BEFORE WE DRY OUT
AGAIN BY LATE AFTERNOON AND THIS EVENING AS SUBSIDENCE SPREADS BACK
OVER THE AREA AHEAD OF THE NEXT TROUGH. THUS...GOING TO BACK OFF POPS
TO MORE SCATTERED COVERAGE TODAY AS MANY AREAS...ESPECIALLY IN THE
EAST MAY NOT MEASURE TODAY OR WILL LIKELY SEE VERY LIGHT RAINFALL.
WINDS ARE THE OTHER CONCERN FOR TODAY AS WINDS ARE ALREADY GUSTING UP
TO 30 MPH THIS MORNING. WITH THE WEAKENING SHOWERS SPREADING INTO THE
AREA...WE MAY TAP INTO SOME HIGHER WINDS ALOFT WITH 40 KNOTS AROUND
900 MB. THIS MAY CREATE SOME VERY GUSTY CONDITIONS AS THIS BAND OF
SHOWERS MOVES EAST THROUGH EARLY AFTERNOON. THUS...WENT AHEAD AND
ISSUED A LAKE WIND ADVISORY THROUGH 23Z TODAY TO ACCOUNT FOR THESE
WINDS.
MEANWHILE...A SHARPER MID LEVEL TROUGH IS CONTINUING TO DIG OVER THE
CENTRAL ROCKIES WITH A NORTHERN STREAM WAVE PUSHING INTO THE NORTHERN
PLAINS. AS THESE TWO SYSTEMS PHASE AND MOVE EAST...IT WILL ACCELERATE
THE COLD FRONT ACROSS EASTERN KENTUCKY LATE TONIGHT. WITH GOOD
DYNAMICS IN PLACE...AND GOOD CONVERGENCE ALONG THE SURFACE
BOUNDARY...WE WILL SEE WIDESPREAD PRECIPITATION DEVELOP AS THIS
BOUNDARY MOVES EAST. A NARROW RIBBON OF INSTABILITY JUST AHEAD OF THE
FRONT COULD LEND ITSELF TO SOME LIGHTNING OVERNIGHT.
HOWEVER...INSTABILITY SHOULD REMAIN ELEVATED...AND POSE NO SEVERE
THREAT. THE BIGGER STORY WILL BE THE RETURN OF MUCH COLDER AIR INTO
EASTERN KENTUCKY FOR TUESDAY. IT DOES APPEAR SOME MOISTURE WILL
LINGER BEHIND THE COLD FRONT YIELDING AN A BRIEF OPPORTUNITY FOR SOME
SNOW TO MIX IN JUST BEFORE PRECIPITATION ENDS. MOST LOCATIONS WILL
ESCAPE ANY SNOW ACCUMULATION AS THE GROUND WILL SIMPLY BE TOO WARM.
THE EXCEPTION WILL BE IN THE HIGHEST TERRAIN ABOVE 2.5KFT AS COLDER
SURFACE TEMPERATURES MAY ALLOW FOR BETTER ACCUMULATION POTENTIAL.
WILL GO WITH UP TO 2 INCHES ON THE HIGHEST PEAKS IN SOUTHEAST
KENTUCKY. PRECIPITATION WILL COME TO AN END THROUGH THE DAY
TUESDAY...BUT SOME DRIZZLE OR FLURRIES COULD LINGER ACROSS THE HIGH
TERRAIN IN THE SOUTHEAST INTO THE AFTERNOON OR EVENING HOURS. HIGHS
WILL STRUGGLE TO REACH 40 ON TUESDAY...WITH HIGHS POSSIBLY OCCURRING
EARLY IN THE DAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 328 AM EDT MON APR 14 2014
LONG TERM DISCUSSION WILL FOLLOW SHORTLY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 232 AM EDT MON APR 14 2014
VFR CONDITIONS WILL LIKELY PERSIST THROUGH THE TAF FORECAST PERIOD.
THE MAIN AVIATION CONCERN WILL BE THE POSSIBILITY OF SOME LOW LEVEL
WIND SHEAR THROUGH THE REMAINDER OF THE OVERNIGHT HOURS. THEN WINDS
WILL RAMP UP BY MORNING WITH GUSTY SOUTH WINDS ANTICIPATED AND THESE
GUSTS COULD REACH AROUND 30 KNOTS AT TIMES THROUGH THE DAY. A FEW
ISOLATED HIGHER WIND GUSTS COULD ALSO BE POSSIBLE IN AND AROUND
SHOWERS WHICH WILL BE ARRIVING AROUND DAYBREAK IN THE WEST. A SHARP
WIND SHIFT IS ANTICIPATED TONIGHT AS A COLD FRONT PUSHES ACROSS
EASTERN KENTUCKY. THIS WIND SHIFT WILL LIKELY OCCUR CLOSER TO
MIDNIGHT OR LATER AS WINDS GO FROM THE SOUTH TO THE WEST AND
NORTHWEST. IN ADDITION...WIDESPREAD PRECIPITATION WILL OVERSPREAD THE
AREA LATE TONIGHT WITH CIGS COMING DOWN LATE TONIGHT TO MVFR OR
LOWER.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY MORNING FOR
KYZ044-050>052-058>060-068-069-079-080-083>088-104-106>120.
LAKE WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR KYZ044-
050>052-058>060-068-069-079-080-083>088-104-106>120.
&&
$$
SHORT TERM...KAS
LONG TERM...HAL
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
535 AM EDT MON APR 14 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 533 AM EDT MON APR 14 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER
THE WEST COAST AND A DOWNSTREAM TROUGH FROM HUDSON BAY THE NRN AND
CNTRL PLAINS. A POTENT WELL DEFINED SHORTWAVE TROUGH WITH COMMA
RADAR SIGNATURE WAS LIFTING NORTHEAST INTO SW WI. THE COMBINATION OF
UPPER LEVEL DIV WITH THE RIGHT ENTRANCE OF THE 140-150 KNOT 300 MB
JET OVER NRN ONTARIO...STRONG QVECTOR CONV AND 700-500 MB FGEN
SUPPORTED MODERATE TO HEAVY SNOW FROM N CNTRL WI THROUGH CNTRL UPPER
MI. RADAR INDICATED THE HIGHER REFLECTIVITY ALIGNED WITH THE MAX
FGEN FROM NEAR IMT TO SE MARQUETTE COUNTY. TWO TO THREE INCHES HAD
FALLEN IN MANY LOCATIONS OF CNTRL UPPER MI BY 09Z WITH ONE INCH TO THE
SE AT ISQ. GIVEN THE WET HEAVY NATURE OF THE SNOW...SLR VALUES WERE
LOW...GENERALLY AT OR BELOW 10/1.
TODAY...AS THE SHORTWAVE LIFTS TO THE NORTHEAST...EXPECT THE SNOW TO
GRADUALLY DIMINISH THIS MORNING AROUND 15Z. ADDITIONAL ACCUMULATIONS
OF 2 TO 3 INCHES WOULD BRING TOTALS INTO THE 3 TO 6 INCH RANGE. THE
STRONG UPSLOPE NRLY FLOW WILL ALSO HELP BOOST SNOW AMOUNTS TOWARD
THE HIGHER END OF THE RANGE OVER THE HIGHER TERRAIN OF N CNTRL UPPER
MI. ALTHOUGH WINDS GUSTING TO 35 MPH WILL ALSO PRODUCE BLOWING
SNOW...THE SNOW WAS WET ENOUGH SO THAT VSBYS WERE MAINLY ABOVE
1/2SM. SOME LOCALIZED LOWER VSBY WOULD BE EXPECTED NEAR THE LAKE
SUPERIOR SHORELINE. AS THE STRONGER DYNAMICS LIFT OUT BY THIS
AFTERNOON SOME LIGHT SNOW WILL CONTINUE INTO THE NORTH AS 850 MB
TEMPS DROPPING TO AROUND -16C AND SOME LIMITED OPEN WATER PROVIDES
ENOUGH HEAT/MOISTURE FOR ADDITIONAL LAKE EFFECT AND OROGRAPHIC SNOW
FOR HIGHER TERRAIN LOCATIONS.
TONIGHT...ANY LINGERING LAKE EFFECT SNOW WILL DIMINISH BUT COULD
STILL PRODUCE A DUSTING OVER THE NORTH. MUCH COLDER AIR WILL MOVE IN
WITH MIN READINGS INTO THE 5F TO 15F RANGE.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 417 AM EDT MON APR 14 2014
LONGWAVE TROUGH AXIS ACROSS THE GREAT LAKES ON TUESDAY. QUITE CHILLY
WITHIN THE TROUGH WITH H85 TEMPS DOWN TO -20C OVER LK SUPERIOR.
SHORTWAVE DROPPING SE IN THE MEAN TROUGH INCREASES DEPTH OF QUALITY
OF MOISTURE AND ALSO STEEPENS H9-H7 LAPSE RATES ON TUESDAY. LAKE
EFFECT FLURRIES MAY TRANSITION TO DIURNALLY DRIVEN SNOW SHOWERS WITH
COVERAGE EXTENDING INLAND TOWARD WI BORDER AND LK MICHIGAN SHORE.
POPS LOW CHANCE AT BEST THOUGH. TEMPS WILL BE VERY COOL FOR THIS
TIME OF YEAR WITH READINGS IN THE LOW-MID 20S NORTH AND AROUND 30
IN THE SOUTHERN CWA. NORMAL HIGHS ARE INTO THE LOWER 50S OVER THE
SOUTH. WAVE MOVES EAST ON TUESDAY EVENING WHICH SHOULD ALLOW SKIES
TO TEMPORARILY CLEAR OUT AHEAD OF NEXT SYSTEM THAT BEGINS TO IMPACT
FAR WEST CWA WITH LGT SNOW LATE TUESDAY NIGHT. MIN TEMPS MAY DIP
INTO SINGLE DIGITS FOR MANY AREAS BEFORE THICKER CLOUDS MOVE BACK
IN LATER DURING THE NIGHT.
WHAT TO DO WITH SYSTEM FOR WEDNESDAY WILL BECOME LARGER FOCUS ONCE
WE GET PAST SYSTEM BRINGING SNOW TO MUCH OF UPR MICHIGAN TODAY. WILL
TWO CAMPS STILL PRESENT IN THE MODELS. NAM/GFS BRING SHORTWAVE AND SFC
LOW PRESSURE AND INVERTED TROUGH ACROSS UPPER MISSISSIPPI RIVER
VALLEY QUICKER...AND HAVE MORE QPF. BOTH CAMPS OF MODELS GENERATE QPF
INTO WESTERN CWA BY 12Z WEDNESDAY...SUPPORTED BY LARGER SCALE
DIFFLUENCE ALOFT BTWN JETS EMERGING FM THE PLAINS AND CROSSING LK
SUPERIOR REGION. ECMWF AND GEM-NH AND UKMET ARE SLOWER AND NOT AS
HEAVY WITH QPF OVER UPR MICHIGAN...KEEPING FOCUS FOR HEAVIER PRECIP
OVER CNTRL MN INTO WCNTRL WI ALONG TRACK OF SFC LOW PRESSURE WAVE
THROUGH MUCH OF WEDNESDAY BEFORE LIFTING IT ACROSS MAINLY WESTERN
HALF OF UPR MICHIGAN LATER WEDNESDAY INTO WEDNESDAY NIGHT. DESPITE
MODEL DIFFERENCES...ENOUGH EVIDENCE TO PUSH POPS TO LIKELY WEDNESDAY
AND WEDNESDAY NIGHT. ALSO THERE IS DECENT AGREEMENT THAT WESTERN AND
PROBABLY CENTRAL CWA WILL SEE MODERATE SNOW AMOUNTS FROM THIS
SYSTEM...WITH BULK OF SNOW FALLING WEDNESDAY AFTN THROUGH EARLY
THURSDAY MORNING. MIXING RATIOS 2.5-3G/KG WOULD SUPPORT MODERATE SNOW
AMOUNTS OF 3 TO 6 INCHES OVER 12 HOUR PERIOD. MODELS SHOWING AREA OF
MID-LEVEL FGEN...FAIRLY STRONG CONSIDERING HOW FAR OUT WE ARE
STILL...THAT COULD RESULT IN BANDS OF HEAVIER SNOW OVER LIKELY THE
WEST CWA. HPC HEAVY SNOW GRAPHICS SHOW MUCH OF FAVORED AREA WITH
MODERATE PROBABILITY OF SEEING 4 INCHES OF SNOW WITH LOW PROBABILITY
OF SEEING 8 INCHES. BASED ON 1000-850MB AND 850-700MB THICKNESSES AND
H85 TEMPS...SNOW WILL MIX WITH AND COULD CHANGE TO RAIN LATER
WEDNESDAY NIGHT OVER SCNTRL AND EAST CWA. RAIN/SNOW MIX CONTINUES
INTO THURSDAY FOR THOSE AREAS WHILE WIDESPREAD SNOW DIMINISHES
ELSEWHERE. NO WATCH ATTM...AS IT WOULD BE LATER 5TH PERIOD AND STILL
NEED TO GET THROUGH THIS ONGOING SNOW SYSTEM TO AVOID ANY CONFUSION.
WILL CONTINUE TO MENTION IN EHWO/HWOMQT.
LATER THURSDAY AND ON INTO NEXT WEEKEND THE FORECAST IS AT BEST
MUDDLED...WHICH LEADS TO LOWER THAN AVERAGE CONFIDENCE FOR SURE. GFS
MORE OR LESS IS FAIRLY CONSISTENT IN SHOWING SHORTWAVE IN SOUTHERN
STREAM LIFTING ACROSS UPPER GREAT LAKES WHILE PHASING WITH NORTHERN
BRANCH SHORTWAVE TROUGH. RESULT IS WRAPPED UP SFC LOW WITH
WIDESPREAD RAIN AND SNOW OVER UPR MICHIGAN. GEM-NH SUPPORTS IDEA
SOMEWHAT THOUGH IT IS SLOWER AND NOT AS STRONG. ECMWF WAS TRENDING
NORTH AND WEST WITH THAT SYSTEM...BUT WITH LATEST RUN NOW HAS WENT
BACK TO THE SOUTHEAST...KEEPING MUCH OF UPR MICHIGAN DRY ON FRIDAY.
ECMWF IS NOT PHASING THE SOUTHERN WAVE NEAR AS MUCH AS GFS ATTEMPTS
TO SHOW. CONSENSUS POPS...CAPPED AT LOW CHANCE...WILL BE UTILIZED
FOR NOW. WHATEVER LOW PRESSURE SYSTEM WOULD BE EXITING TO START THE
WEEKEND...WITH HIGH PRESSURE AND DRIER WEATHER FOR THE REST OF THE
WEEKEND AS SHOWN BY GFS. NOT SO INDICATES THE ECMWF...WITH A QUICK
PUSH OF NEXT SHORTWAVE ENERGY AND SFC TROUGH/RAIN SHOWERS FOR
SUNDAY. LATEST RUN BACKED OFF SOME...BUT JUST SHOWS THE HIGH
VARIABILITY THAT CURRENTLY EXISTS FOR THAT FORECAST TIME FRAME. ONE
PRETTY SURE THING IS IT LOOKS LIKE WARMING TREND /TEMPS TRYING TO
RETURN TOWARD AVERAGE/ DEVELOPS NEXT WEEKEND AFTER WHAT APPEARS TO
BE A CHILLY MID APRIL WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 138 AM EDT MON APR 14 2014
SAW...A LO PRES MOVING FM IOWA THRU NRN LWR MI MON MRNG WL BRING A
PERIOD OF SN TO SAW EARLY THIS MRNG. WITH AN INCRSG N UPSLOPE WIND
THAT WL GUST AS HI AS 30 KTS AND CONTRIBUTE TO SOME BLSN AS WELL...
EXPECT CONDITIONS TO DETERIORATE TO IFR/LIFR FOR AT LEAST SEVERAL
HRS THRU 12Z. THE ARRIVAL OF DRIER AIR...DAYTIME HEATING AND SLOWLY
WEAKENING PRES GRADIENT/WINDS WL BRING MVFR CONDITIONS AFT SUNRISE
ON MON.
IWD/CMX...SN ASSOCIATED WITH THE LO PRES MOVING THRU THE LKS LATE
TNGT WL MISS THESE LOCATIONS TO THE E. BUT WITH A FVRBL...INCRSG
UPSLOPE N WIND AT IWD...MVFR CIGS SHOULD PREDOMINATE AT THAT
LOCATION. BEST CHC FOR SOME IMPROVEMENT TO VFR AT IWD WL BE MON
AFTN...WHEN DAYTIME HEATING MIGHT LIFT THE CLD BASE INTO THE VFR
RANGE. SINCE THIS N WIND IS NOT AS FVRBL FOR CMX AND THE INCOMING
LLVL AIRMASS IS ON THE DRY SIDE...THIS SITE WL EXPERIENCE PERIODS OF
VFR CIGS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 417 AM EDT MON APR 14 2014
NORTH GALES 35-40 KNOTS FOR TODAY...MAINLY EAST HALF...AS LOW
PRESSURE SYSTEM TRACKS ACROSS LOWER MICHIGAN THIS MORNING AND
EVENTUALLY ACROSS QUEBEC BY THIS EVENING. WINDS QUICKLY DIMINISH
BY THIS EVENING AND SHOULD REMAIN BLO 20 KTS OVER MOST OF THE LAKE
THROUGH TUESDAY. LOW PRESSURE SYSTEM LIFTING ACROSS UPPER GREAT
LAKES LATER ON WEDNESDAY WILL RESULT IN EAST TO NORTHEAST WINDS UP
TO 25 KTS OVER MAINLY WESTERN LAKE INTO THURSDAY. WINDS DIMINISH TO
LESS THAN 20 KTS REST OF THE FORECAST PERIOD.
&&
.HYDROLOGY...
ISSUED AT 417 AM EDT MON APR 14 2014
REPORTS OF ICE JAMS IN DELTA COUNTY SUNDAY ON ESCANABA RIVER AND
ASSOCIATED TRIBUTARIES. HYDROLOGIC STATEMENT WAS ISSUED SUNDAY
EVENING AND THIS IS VALID THROUGH THIS EVENING. PRECIPITATION OCCURS
MAINLY IN THE FORM OF SNOW TODAY. OPPORTUNITIES FOR WIDESPREAD
PRECIPITATION ALSO IN THE FORECAST FOR WEDNESDAY THROUGH THURSDAY...
AND POSSIBLY FRIDAY. FEASIBLE THAT TOTAL PRECIPITATION FOR THIS WEEK
MAY EXCEED AN INCH IN SOME AREAS OF UPPER MICHIGAN. THIS PRECIP
ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES
OVER MAINLY WESTERN UPPER MICHIGAN WILL RESULT IN ANOTHER PERIOD
OF SNOWMELT AND RUNOFF ONCE WARMER TEMPERATURES MOVE BACK INTO THE
REGION BY NEXT WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 7 AM CDT THIS MORNING FOR MIZ010-
011.
WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ006-
007-013-014-085.
WINTER WEATHER ADVISORY UNTIL 11 AM EDT /10 AM CDT/ THIS MORNING
FOR MIZ005-012.
LAKE SUPERIOR...
GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR LSZ249>251-266-
267.
GALE WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR LSZ244-245-264-
265.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...KC
MARINE...JLA
HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
325 AM EDT MON APR 14 2014
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM
.SYNOPSIS...
ISSUED AT 325 AM EDT MON APR 14 2014
A LOW PRESSURE SYSTEM CENTERED NEAR CHICAGO EARLY THIS MORNING
WILL CONTINUE TO BRING RAIN SHOWERS TODAY. PRECIPITATION WILL
GRADUALLY BECOME MIXED WITH AND CHANGE OVER TO SNOW SHOWERS AS
COLDER AIR MOVES IN ON THE BACK SIDE OF A LOW PRESSURE SYSTEM THAT
WILL CONTINUE TO TRACK NORTHEAST INTO ONTARIO. IT WILL BE BREEZY
TODAY AS WELL. TEMPERATURES WILL BE UNSEASONABLY COLD TUESDAY
BEFORE UNDERGOING A MODERATING TREND WEDNESDAY THROUGH THURSDAY.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 325 AM EDT MON APR 14 2014
SHOWERS WILL CONTINUE TO LINGER THIS MORNING AS LOW PRESSURE NEAR
ORD EARLY THIS MORNING TRACKS NE TO SAGINAW BAY BY 12Z AND FURTHER
NE INTO ONTARIO BY MIDDAY. FAIRLY WINDY CONDITIONS ARE ANTICIPATED
TODAY AS BRISK NW FLOW CAA OCCURS ON THE BACK SIDE OF THE SYSTEM.
GUSTY WINDS ARE ALREADY NOTED OVER NORTH/CENTRAL IL INTO NORTHERN
INDIANA. HIGHER RES GUIDANCE SUCH AS THE HRRR SUGGESTS SOME GUSTS
MAY BRIEFLY REACH AROUND 40 TO NEAR 45 MPH ALONG I-94 AND ESPECIALLY
IN OUR FAR SE FCST AREA TOWARD JXN LATER THIS MORNING. THIS IN
ADDITION TO A FEW GUSTS TO AROUND 40 TO 45 MPH RIGHT ALONG THE LAKE
MI SHORELINE. OVERALL THOUGH FELT A WIND ADVISORY IS NOT NEEDED
TODAY SINCE THE MAJORITY OF OUR AREA WILL NOT SEE GUSTS AS HIGH AS
45 MPH.
PCPN WILL GRADUALLY BECOME MIXED WITH THEN CHANGE OVER TO LIGHT
SNOW SHOWERS FROM NW TO SE ACROSS OUR FCST AREA TODAY AS THE CAA
OCCURS. VERY LITTLE TO NO ACCUMULATION IS EXPECTED TODAY. HOWEVER
AS TEMPERATURES CONTINUE TO FALL INTO THE 20S TONIGHT WE DO EXPECT
LIGHT ACCUMULATIONS ACROSS MOST OF OUR FCST AREA RANGING FROM A
FEW TENTHS OF AN INCH TO LOCALLY AS MUCH AS TWO INCHES. LINGERING
LIGHT SNOW SHOWERS TUESDAY MORNING WILL TAPER OFF TO FLURRIES BEFORE
ENDING AND IT WILL BE UNSEASONABLY COLD WITH MAX TEMPS ONLY IN THE
30S.
HIGH PRESSURE WILL BUILD IN TO PRODUCE FAIR BUT COLD WX TUESDAY
NIGHT. FAIR WX WILL CONTINUE WEDNESDAY ALONG WITH MUCH MILDER
TEMPS AS FLOW BECOMES SOUTHERLY ON THE BACKSIDE OF THE DEPARTING
HIGH.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 325 AM EDT MON APR 14 2014
NO BIG STORMS EXPECTED IN THE EXTENDED PERIOD. THERE WILL BE SOME
RAIN BUT CONVECTION IS NOT LIKELY SO AMOUNTS SHOULD NOT BE
EXCESSIVE. TWO LOW PRESSURE CENTERS WILL BE MOVING THROUGH FROM
WEDNESDAY NIGHT INTO SATURDAY NIGHT WITH THE HIGHEST CHANCES FOR
RAIN ON FRIDAY NIGHT. MODEL SOUNDINGS SUGGEST RAIN COULD MIX WITH
WET SNOW ACROSS THE NORTH WEDNESDAY NIGHT AND AGAIN SATURDAY NIGHT
BUT CONDITIONS WERE MARGINAL ENOUGH TO LEAVE OUT OF THE FORECAST.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 744 PM EDT SUN APR 13 2014
IMPACTS WILL INCREASE THROUGH THE NIGHT FOR AVIATORS. IFR LOOKS
LIKELY ESPECIALLY KGRR AND KMKG WITH THE HEAVIER RAIN.
THUNDERSTORMS WILL BE AROUND AS WELL ESPECIALLY WEST OF KLAN AND
KJXN.
WINDS WILL INCREASE AND VALUES OVER 30 KTS EXPECTED. A SHARP WIND
SHIFT IS EXPECTED MONDAY MORNING INTO THE AFTERNOON. TEMPERATURES
WILL TURN COLDER AFTER THE WIND SHIFT. ICING MAY BECOME AN ISSUE
MONDAY AFTERNOON.
&&
.HYDROLOGY...
ISSUED AT 343 PM EDT SUN APR 13 2014
HAVE MAINTAINED THE FLOOD WATCH FOR THE ORIGINAL AREA. THE HEAVY
RAIN HAS FALLEN ACROSS THE WATCH AREA WHICH HAS WORKED OUT WELL.
AREAL FLOOD WARNINGS ARE IN PLACE FOR CENTRAL LOWER MICHIGAN OR THE
NORTHERN THREE ROWS OF THE GRR FORECAST AREA FROM
MUSKEGON...NEWAYGO...MONTCALM AND GRATIOT COUNTIES NORTHWARD.
QUITE A FEW RAINFALL TOTALS HAVE BEEN RECEIVED ACROSS CENTRAL LOWER
IN EXCESS OF 3 INCHES...WITH THE HIGHEST BEING NEAR THE MASON/OCEANA
COUNTY LINE NORTH OF MONTAGUE AT 3.82 INCHES.
ANOTHER BATCH OF SHOWERS AND STORMS WILL WORK THROUGH THE AREA
BETWEEN ABOUT 600 PM THIS EVENING THROUGH MONDAY MORNING. AN
ADDITIONAL 1 TO 2 INCHES OF RAIN IS EXPECTED WITH LOCALLY HIGHER
AMOUNTS ACROSS CENTRAL LOWER MI WHERE THEY DO NOT NEED ANY MORE
RAIN. THE AREAL FLOOD WARNING WILL LIKELY NEED TO BE EXTENDED AS THE
NEXT BATCH OF RAIN WILL RESULT IN ADDITIONAL FLOODING. NUMEROUS
RIVER ADVISORIES AND WARNINGS ARE IN PLACE WITH POTENTIALLY MORE TO
COME. SEVERAL SITES ARE FORECAST TO MOVE INTO THE MODERATE FLOOD
CATEGORY WHICH IS SIGNIFICANT FLOODING. SOME OF THE RAIN TONIGHT MAY
BE THE HEAVIEST OF THIS ENTIRE EVENT AS PARAMETERS LIKE PWAT (DEEP
MOISTURE) PEAK TONIGHT.
THE HEAVIER RAIN WILL COME TO AN END MIDDAY ON MONDAY MIXING WITH
AND CHANGING OVER TO SNOW DURING THE AFTERNOON AND OVERNIGHT.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...FLOOD WATCH UNTIL 11 AM EDT THIS MORNING FOR MIZ037>040-043>046-
050>052-056>058-064.
LM...NONE.
&&
$$
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...OSTUNO
AVIATION...MJS
HYDROLOGY...DUKE
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1115 PM CDT Sun Apr 13 2014
.UPDATE:
Issued at 903 PM CDT Sun Apr 13 2014
Two areas of SHRA/TSRA of interest at the moment. The first area
moved thru southeast MO and into STL Metro earlier this evening
and has dropped up to 1.25" of rain in spots with many areas
receiving between 0.3 and 0.75" in the main area of effect. No
severe weather is anticipated here with the atmosphere worked over
well and not that unstable. Some elevated instability, though, has
produced imbedded thunder.
The other area is a squall line that had developed over western MO
and eastern KS this afternoon and has progressed steadily
eastward, but has thus far produced wind gusts up to 50mph. Severe
thunderstorm watch #75 continues for a reduced area in east-
central MO until midnight CDT, but anticipate this watch being
cancelled probably around 10-1030pm given current trends and
timing of progression of thunderstorm line.
All of this will exit STL metro during the early overnight and
late tonight in southwest IL. The next round of more stratiform
frontogenetical pcpn is not anticipated until mid-late Monday
morning in central MO, expanding elsewhere later on Monday. It is
with this area of pcpn, and behind an increasingly chilly airmass,
that some snow will be possible, but it remains doubtful on
ability to accumulate considering warm ground and surface temps
above freezing throughout. Nevertheless, the mere presence of
falling snow in mid-April rather unusual in these parts.
TES
&&
.SHORT TERM: (Through Late Tonight)
Issued at 359 PM CDT Sun Apr 13 2014
(Tonight-Monday Night)
Main question tonight will be severe weather chances. Large area of
stratiform rain currently over the CWA may suppress these chances as
latest SPC objective MUCAPE analysis is mostly below 500 j/kg except
across northern Missouri and west central Illinois. The latest runs
of the HRRR has been trending toward weaker storms these evening
because weaker instability. However, if the rain can mover out of
the area, there are very steep lapse rates over the Central Plains
that could help quickly destabilize the atmosphere ahead of the line
of the storms currently over eastern Kansas. Deep layer shear
between 00-03Z will be between 35-50kts which will be sufficient for
organized severe storms.
Otherwise, forecast did not require too much changes as I still
expect front to march southeast across the CWA tonight.
Thunderstorm threat will end with the front and change to a plain
cold rain. Have kept likely chances to for rain on Monday as the
ECMWF/GFS/NAM all mid-level frontogenesis moving across the region
during the day. Also added likely chances over the eastern counties
on Monday evening as ascent from the mid level trough will not clear
the CWA until overnight Monday night. Forecast soundings and
critical thicknesses still point to snow mixing with the rain from
northwest to southeast during the day on Monday. Do not have any
accumulating snow at the moment as the low atmosphere will be rather
warm during the day, as will the surface temperatures after this
unseasonably warm weekend.
With the much colder air moving into the area, temperatures will
fall below freezing over the entire CWA on Monday night. Many areas
will see temperatures in the mid to upper 20s.
Britt
.LONG TERM: (Monday through Next Sunday)
Issued at 359 PM CDT Sun Apr 13 2014
(Tuesday-Sunday)
Upper trough will move east of the area by Tuesday bringing dry
weather for mid week. While Monday night looks like the coldest,
Tuesday night will likely still have temperatures around freezing
before lows become more seasonable later in the week.
While the ECMWF has trended deeper and consequently slower with the
trough that will move through the central CONUS late this week, it
is still not as deep as the GFS or the Canadian GEM. Will stick
with the more consistent ECMWF as the GFS is quicker to move the
front through the area on Thursday night than it was before. Will
keep Thursday dry with the front staying to the northwest most of
the day with a chance of showers Thursday night and Friday as the
front moves across the area. By next weekend, winds turn out of the
southwest quickly behind a retreating high allowing gulf moisture to
move north from the Gulf quickly into the area.
Britt
&&
.AVIATION: (For the 06z TAFs through 06z Monday Night)
Issued at 1028 PM CDT Sun Apr 13 2014
Cold front extending from a surface low over northwestern IL
southwest through UIN and COU will move sewd through the St Louis
metro area just after 06z Monday. The more significant showers and
storms will shift east of the taf sites by 06z Monday, but there
may be lingering patchy light rain or isolated light showers til
around 08z Monday. Surface winds will veer around to a nwly
direction after fropa, and will be relatively strong and gusty late
tonight and Monday due to a tight surface pressure gradient. The
wind will gradually diminish Monday night as a surface ridge
approaches and the surface pressure gradient relaxes. Ceilings
will likely fall into the IFR catagory behind this front, down to
around 1000 ft or slightly lower late tonight and early Monday
morning. The cloud ceiling will gradually rise Monday afternoon,
becoming VFR Monday evening. There will be some light rain mainly
Monday afternoon as an upper level disturbance moves through the
area, possibly mixing with or changing to light snow in UIN and
COU as colder air continues to filter sewd into the area.
Specifics for KSTL: The cold front will move southeastward through
STL just after 06z Monday. The more significant showers and
storms will shift east of STL by 06z Monday, but there may be
lingering post frontal patchy light rain or isolated light showers
until around 08z Monday. The surface wind will veer around to a
nwly direction late tonight after fropa. The wind will remain
strong and gusty through Monday, then diminish Monday night. The
cloud ceiling will lower into the IFR catagory late tonight and
early Monday morning after fropa. The cloud ceiling will gradually
rise into the MVFR catagory Monday afternoon, VFR Monday evening,
then finally clearing out completely late Monday night. Periods
of light rain can be expected Monday afternoon, possibly changing
to a little light rain/snow mix before ending early Monday evening.
GKS
&&
.CLIMATE:
RECORD LOWS FOR 4/15:
STL - 27 IN 1928
COU - 25 IN 1928
UIN - 24 IN 1928
FAM - 24 IN 1928
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...CORRECTED
NWS NORTH PLATTE NE
359 AM CDT MON APR 14 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT MON APR 14 2014
A WEAK UPPER LEVEL DISTURBANCE...CURRENTLY ACROSS ERN MT/WRN ND...
WILL DROP SOUTH THROUGH THE FCST AREA TODAY. LAPSE RATES FROM
850-700MB ARE STEEP AND MOIST BUT THE 850MB-SFC LAYER IS VERY DRY
WITH DEW POINTS IN THE TEENS AND LOWER 20S. WHILE TEMPERATURE RISE
IN THE LOW TO MID 40S THIS AFTN...WET BULB ZERO HEIGHTS WITH BE
CLOSE TO THE GROUND AND THE HRRR AND RAP SHOW SNOW FOR THE PTYPE. SO
ISOLATED SNOW SHOWERS ARE IN THE FORECAST.
NO MEASURABLE QPF WAS INDICATED IN THE RAP SOLN BUT THE HRRR
ACTUALLY SHOWS SCATTERED SNOW SHOWERS WITH SEVERAL STREAKS OF 0.01
QPF AND THE MODEL CONSENSUS INDICATES H700MB AROUND -18C AT KVTN
WHICH IS VERY IMPRESSIVE FOR MID APRIL.
THIS DISTURBANCE WILL DRAW ANOTHER WEAK PIECE OF ARCTIC HIGH
PRESSURE INTO THE ERN HALF OF THE FORECAST AREA TONIGHT WHILE THE
WRN HALF DEVELOPS SOUTH WINDS AS LOW PRESSURE FORMS ACROSS THE NRN
HIGH PLAINS. LOWS TONIGHT SHOULD FALL INTO THE LOW TO MID 20S WITH
GENERALLY CLEAR SKIES.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 345 AM CDT MON APR 14 2014
WARM AIR QUICKLY SPREADS NORTHEAST INTO THE REGION TUESDAY...WITH
H85 TEMPS RISING TO 8C TO 12C BY AFTERNOON. THIS SHOULD YIELD HIGHS
IN THE UPPER 50S TO MID 60S. HAVE RAISED LOWS TUESDAY NIGHT...AS
SOUTHERLY LOW LEVEL JET KEEPS ATMOSPHERE MIXED AND H85 TEMPS
CONTINUE TO WARM...NEARING 13C.
SHORTWAVE ENERGY DIVES SOUTHEAST INTO THE PLAINS LATE WEDNESDAY
THROUGH THURSDAY. MODELS CONTINUE TO MOVE THIS THROUGH QUICKLY AS AN
OPEN WAVE...WITH THE BEST UPPER LEVEL DYNAMICS CROSSING THROUGH
NORTHERN KANSAS. WILL CONTINUE THE HIGHEST POPS /NEAR 40 PERCENT/
ACROSS FAR SOUTHERN NEBRASKA. SOUNDING PROFILES INDICATE A MIX OF
RAIN AND SNOW OR WET SNOW...BUT NOT EXPECTING MUCH QPF AT THIS
POINT. CHILLY WEATHER IN THE WAKE OF THE SYSTEM THURSDAY...AS MORE
ARCTIC AIR MOVES SOUTH INTO THE PLAINS.
AS WE HEAD INTO NEXT WEEKEND...THE GFS AND ECMWF ARE BOTH
ADVERTISING UPPER LEVEL ENERGY ADVANCING EASTWARD FROM THE PACIFIC
INTO THE SOUTHWEST CONUS. THIS AIDS IN THE DEVELOPMENT OF A SURFACE
TROUGH ALONG THE HIGH PLAINS...WITH SOUTHERLY FLOW EAST OF THE
TROUGH DRAWING GULF MOISTURE NORTHWARD INTO THE PLAINS. IT WOULD
APPEAR THAT SOME TSTM ACTIVITY IS POSSIBLE SATURDAY NIGHT ON THE
NOSE OF A SOUTHERLY LOW LEVEL JET...AND THEN PERHAPS SUNDAY AS A
COLD FRONT AND LOW PRESSURE SYSTEM ADVANCE EAST ACROSS THE AREA.
ALTHOUGH BOTH MODELS DRAW MOISTURE NORTH INTO THE PLAINS...THERE ARE
DIFFERENCES IN THE HANDLING OF THE UPPER LEVEL ENERGY ACROSS THE
SOUTHWEST CONUS. WILL LEAVE THE FORECAST DRY AT THIS TIME...AS THE
MODELS SEEM TO BE JUST STARTING TO LATCH ONTO THIS SCENARIO. IF THIS
CONTINUES TO BE SHOWN IN FUTURE MODEL RUNS...THEN SOME THUNDER
MENTION WILL HAVE TO BE ADDED TO THE WEEKEND FORECAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1128 PM CDT SUN APR 13 2014
EXPECT MID AND HIGH LEVEL CLOUDINESS TO PERSIST INTO THE OVERNIGHT
HOURS...ESPECIALLY AT THE KLBF TERMINAL WHERE CIGS WILL RANGE FROM
9000 TO 12000 FT AGL OVERNIGHT. FOR THE KVTN TERMINAL...SCATTERED
HIGH CLOUDINESS AON 25000 FT AGL SHOULD SET IN OVERNIGHT. FOR BOTH
TERMINALS...AN UPPER LEVEL TROUGH WILL DIVE SOUTH FROM THE DAKOTAS
INTO NEBRASKA ON MONDAY. THIS FEATURE WILL STEEPEN MID LEVEL LAPSE
RATES...LEADING TO BROKEN CIGS AROUND 6000 FT AGL LATE MONDAY
MORNING INTO THE AFTERNOON HOURS. SKIES WILL CLEAR TOWARD SUNSET
MONDAY EVENING. WINDS WILL BE FROM THE NORTH OR NORTHWEST AT 10 TO
20 KTS OVER THE NEXT 24 HOURS. SOME GUSTS MAY APPROACH 25 KTS LATE
MONDAY MORNING THROUGH MONDAY AFTERNOON.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1129 PM CDT SUN APR 13 2014
.UPDATE...
ISSUED AT 623 PM CDT SUN APR 13 2014
JUST UPDATED THE FORECAST TO CANCEL THE WINTER WEATHER ADVISORY
FROM CUSTER...GARFIELD AND WHEELER COUNTIES. SNOW HAS ENDED IN
THESE AREAS...HOWEVER SOME VERY LIGHT SNOW IS POSSIBLE ACROSS THE
SOUTHEASTERN NEBRASKA PANHANDLE AND FAR SOUTHWESTERN NEBRASKA THIS
EVENING. RADAR RETURNS FROM COLORADO AND FAR SERN
WYOMING...INDICATE A NICE AREA OF LIGHT TO MODERATE SNOW IN NERN
COLORADO IN ASSOCIATION WITH A TRAILING DISTURBANCE OVER FAR SERN
UT. THE LATEST RAP AND NAM SOLNS...ALLOW THIS SNOW TO DRIFT INTO
THE FAR SOUTHWESTERN FORECAST AREA THROUGH MID EVENING...THEN
SHIFTING IT SOUTH INTO KANSAS BY LATE EVENING. LITTLE OR NO
ADDITIONAL ACCUMULATIONS ARE EXPECTED WITH ANY SNOW WHICH MOVES
INTO THE FORECAST AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 345 PM CDT SUN APR 13 2014
AT 19Z...WATER VAPOR IMAGERY SHOWED A SHORTWAVE TROUGH MOVING ACROSS
CENTRAL NEBRASKA/KANSAS WITH A GOOD RIDGE DOWNSTREAM ACROSS THE
EASTERN HALF OF THE COUNTRY. LOOKING UPSTREAM...ANOTHER SHORTWAVE
TROUGH HAD BEEN DIGGING SOUTH THROUGH THE DAY...FROM THE PACIFIC
NORTHWEST DOWN OVER UTAH AT THE CURRENT TIME. THE SHORTWAVE OVER THE
LOCAL AREA HAD AN ASSOCIATED SURFACE LOW IN EASTERN KANSAS...WITH A
COLD FRONT INTO THE SOUTHERN PLAINS AND A WARM FRONT TO THE
NORTHEAST INTO IOWA. COLD AIR ADVECTION WAS ONGOING THROUGH THE
DAY...AND AS THE WET BULB TEMPERATURE DROPPED BELOW THE FREEZING
MARK BY EARLY TO MID MORNING...MUCH OF THE PRECIPITATION LOCALLY
FELL AS SNOW. MID LEVEL FRONTOGENESIS HAD BEEN ONGOING THROUGH THE
DAY AS THE 700MB LOW TRACKED JUST SOUTHEAST OF THE FORECAST
AREA...FROM NORTHWEST KANSAS INTO SOUTH CENTRAL NEBRASKA.
PRECIPITATION DEVELOPED IN THIS AREA. THE FRONTOGENETICAL FORCING
HAS SHIFTED EAST THROUGH THE DAY...WHICH ALLOWED THE PRECIPITATION
TO ALSO SHIFT EAST THROUGH THE DAY AND BY MID AFTERNOON HAS MOSTLY
ENDED. THERE WERE SEVERAL STRONGER BANDS OF SNOW THAT
DEVELOPED...WHICH DROPPED AS MUCH AS 5 INCHES OF SNOW IN PARTS OF
THE FORECAST AREA.
AT 20Z...MODERATE SNOWFALL DID CONTINUE FROM CURTIS TO BROKEN BOW TO
ALMERIA...WITH VERY LIGHT SNOW STILL IN AREAS TO THE WEST. THE
WINTER WEATHER ADVISORY WILL BE CANCELLED EARLY FOR THOSE LOCATIONS
WHERE THE HEAVIER SNOW HAS ENDED AS HAZARDOUS WEATHER CONDITIONS
HAVE GENERALLY ENDED. THERE COULD BE A FEW LOCATIONS WHERE ROADWAYS
MAY REMAIN SLICK...BUT ANY FOLLOWING WEATHER CONDITIONS WILL NOT
MAKE THINGS WORSE.
WINDS WILL REMAIN STRONG INTO THE EVENING...BUT WILL START TO
SLOWLY DIMINISH AS THE SURFACE LOW CONTINUES TO THE NORTHEAST
ALLOWING THE PRESSURE GRADIENT TO SLACKEN. WINDS HAVE LARGELY BEEN
JUST BELOW WIND ADVISORY CRITERIA /SUSTAINED OF 30 MPH AND GUSTS OF
45 MPH/ IN THE PAST SEVERAL HOURS. COULD STILL GET A FEW HIGHER
READINGS YET THIS AFTERNOON BUT FEEL THIS WOULD BE MORE LOCALIZED SO
NO NEED FOR ADDITIONAL WIND HEADLINES.
THE SNOW OCCURRING AT THE PRESENT TIME WILL CONTINUE TO SHIFT EAST
THROUGH THIS EVENING AND WILL BE MOSTLY OUT OF THE FORECAST AREA BY
00Z. AFTER 00Z...CHANCES FOR PRECIPITATION WILL BE FOCUSED OVER THE
SOUTHWEST AS THE UPPER LEVEL SYSTEM OVER UTAH KICKS EAST OVERNIGHT.
THAT SYSTEM HAS BEEN TRENDING FURTHER SOUTH OVER THE PAST FEW
DAYS...AND 12Z MODEL RUNS ARE FAIRLY CONSISTENT KEEPING
PRECIPITATION TONIGHT SOUTH OF THE AREA...ACROSS COLORADO AND
KANSAS. DID TREND THE FORECAST DRIER FOR THE EVENING...BUT KEPT
SLIGHT CHANCES FOR THE FAR SOUTHWEST IN CASE OF A SLIGHT SHIFT.
COLDER AIR WILL STAY IN PLACE AS ANOTHER LOW PRESSURE SYSTEM OUT OF
CANADA MOVES INTO THE NORTHERN PLAINS. THIS SYSTEM WILL JUST ENHANCE
THE INFLUENCE OF THE COLDER AIR BY KEEPING IT HERE RATHER THAN
LETTING IT DRIFT EAST. SKIES ARE EXPECTED TO CLEAR OUT BY MONDAY
MORNING...AND WITH THE NEW SNOW...MAY GET SOME RADIATIONAL COOLING
TO HELP COOL THE SURFACE OVERNIGHT. LOWS TONIGHT WERE DROPPED
SLIGHTLY...WITH LOWS IN THE LOW TO MID 20S LIKELY. THEN FOR
MONDAY...THE MODELS ARE SLOW TO MOVE THE COLDER AIRMASS OUT OF THE
AREA...AND ALTHOUGH IT IS MID APRIL...THINK THE SNOW MAY HAVE A
SLIGHT INFLUENCE SO DID DROP HIGHS A FEW DEGREES FOR MONDAY. NOW
LOOKING AT HIGHS IN THE 40S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 PM CDT SUN APR 13 2014
LIGHT SOUTH AND SOUTHWEST WINDS TO DEVELOP MONDAY NIGHT. LOWS WILL
BE SUB FREEZING IN THE LOW TO MID 20S AS LOW DEWPOINTS DICTATE
STRONG COOLING OVERNIGHT.
ON TUESDAY...AN UPSTREAM SHORT WAVE TROUGH DROPS INTO MONTANA AND
IDAHO...TEMPERATURES WILL RECOVERY SIGNIFICANTLY INTO THE LOWER 60S
AS THERMAL RIDGE BUILDS INTO THE CENTRAL HIGH PLAINS.
A COLD FRONT WILL MOVE INTO THE NORTHWEST ZONES TUESDAY NIGHT AS
SCATTERED PRECIPITATION MOVES INTO WYOMING AND THE BLACK HILLS
REGION. LOWS NOT AS COLD IN THE MID 30S. THEN ON WEDNESDAY...A
CHANCE FOR SHOWERS IN NORTH CENTRAL NEBRASKA WITH A COLD FRONT
SWEEPING THE REMAINING FA BY 18Z. THE NAM MODEL IS QUITE A BIT
WARMER WITH H85 TEMPS 4C TO 6C. WILL GO BETWEEN THE COLDER GFS OF 0C
TO -6C. WILL GO NEARER THE NAM SOLUTION WITH MID 50S SOUTHEAST TO
THE MID 40S NORTHWEST. ALSO BREEZY NORTHWEST WINDS. LOWERED POPS
SLIGHTLY WEDNESDAY NIGHT INTO THURSDAY AS SYSTEM LOOKING TO MATURE
ACROSS COLORADO INTO KANSAS AND SERN NEBR. PRECIPITATION TYPE RAIN
OR SNOW WEDNESDAY EVENING...SNOW OVERNIGHT INTO THURSDAY
MORNING...THEN BACK TO RAIN OR SNOW THURSDAY AFTERNOON. HIGHS
THURSDAY CLOSE TO PREVIOUS FORECAST IN THE LOWER 40S.
FOR FRIDAY THROUGH SUNDAY...A DAILY WARMING TREND. AN UPPER RIDGE
IN THE WESTERN CONUS WILL GRADUALLY BUILD EAST INTO THE ROCKIES BY
SUNDAY WITH MUCH MILDER AIR RETURNING TO THE PLAINS. HIGHS IN THE
50S FRIDAY...60S SATURDAY...THEN NEAR 70 SUNDAY. DRY THROUGH THE
PERIOD AS WELL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1128 PM CDT SUN APR 13 2014
EXPECT MID AND HIGH LEVEL CLOUDINESS TO PERSIST INTO THE OVERNIGHT
HOURS...ESPECIALLY AT THE KLBF TERMINAL WHERE CIGS WILL RANGE FROM
9000 TO 12000 FT AGL OVERNIGHT. FOR THE KVTN TERMINAL...SCATTERED
HIGH CLOUDINESS AON 25000 FT AGL SHOULD SET IN OVERNIGHT. FOR BOTH
TERMINALS...AN UPPER LEVEL TROUGH WILL DIVE SOUTH FROM THE DAKOTAS
INTO NEBRASKA ON MONDAY. THIS FEATURE WILL STEEPEN MID LEVEL LAPSE
RATES...LEADING TO BROKEN CIGS AROUND 6000 FT AGL LATE MONDAY
MORNING INTO THE AFTERNOON HOURS. SKIES WILL CLEAR TOWARD SUNSET
MONDAY EVENING. WINDS WILL BE FROM THE NORTH OR NORTHWEST AT 10 TO
20 KTS OVER THE NEXT 24 HOURS. SOME GUSTS MAY APPROACH 25 KTS LATE
MONDAY MORNING THROUGH MONDAY AFTERNOON.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CLB
SHORT TERM...BROOKS
LONG TERM...ROBERG
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1118 PM CDT SUN APR 13 2014
.UPDATE...
ISSUED AT 1106 PM CDT SUN APR 13 2014
PERSISTENT BAND OF SNOW ASSOCIATED WITH WEAK MID LEVEL SHORTWAVE
WAS DRIFTING SOUTHEAST THROUGH EASTERN NEBRASKA AND SOUTHWEST IOWA
AS OF LATE EVENING. BACK EDGE OF SNOW WAS WORKING THROUGH WESTERN
DOUGLAS COUNTY AS OF 11 PM...AND SNOW HAD ENDED AT THE LINCOLN
AIRPORT. BANDED STRUCTURE OF RADAR RETURNS SUGGESTS SOME POCKETS
OF MODERATE SNOW WILL CONTINUE AS THE WHOLE AREA SHIFTS INTO
SOUTHEAST NEBRASKA AND SOUTHWEST IOWA. SPOTTER REPORTS WITHIN THE
BANDS INDICATE SNOW AMOUNTS REMAIN UNDER AN INCH...AND MOSTLY ON
GRASSY AREAS. BUT WEBCAMS SHOW ACCUMULATION ON ROADS UNDER
HEAVIEST BANDS WHICH ARE PRODUCING SLUSHY DRIVING CONDITIONS FOR A
TIME BEFORE MELTING OCCURS. CURRENT TRENDS OF THE FORECAST REMAIN
ON TRACK WITH AREAS EAST OF A MISSOURI VALLEY TO OMAHA AND
LINCOLN LINE EXPERIENCING A FEW HOURS OF LIGHT SNOW WITH AN
OCCASIONAL BURST OF MODERATE SNOW. EXPECT ALL THE SNOW TO BE EAST
OF SOUTHWEST IOWA BY ABOUT 4 AM.
&&
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY)
ISSUED AT 220 PM CDT SUN APR 13 2014
PRIMARY FORECAST CONCERN WILL BE WITH THE FIRST 12 HOURS OF THE
FORECAST AND ITS VARIETY OF WEATHER ACROSS THE AREA.
COLDER AIR CONTINUES ITS SLOW ADVANCE INTO EASTERN NEBRASKA AT 19Z
WITH SNOW NOW FALLING ACROSS NORTHEAST NEBRASKA WEST OF A COLUMBUS
TO SIOUX CITY LINE. SHORT RANGE MODELS SUCH AS THE HRRR SUGGEST
MAIN ORIENTATION OF THE SNOW BAND WILL GENERALLY SETUP IN AN AREA
BOUNDED BY COLUMBUS TO TEKAMAH ON THE SOUTH AND YANKTON TO NELIGH
ON THE NORTH THROUGH THE REMAINDER OF THE AFTERNOON AS MID LEVEL
CLOSED LOW TRACKS EAST INTO CENTRAL IOWA. SNOW THEN SPREADS EAST
AND ENDS FROM THE WEST DURING THE EVENING ACROSS THE REMAINDER OF
EASTERN NEBRASKA AND SOUTHWEST IOWA AS THE MID LEVEL LOW CONTINUES
TO LIFT TOWARD THE GREAT LAKES REGION AND THE SURFACE LOW MOVES
INTO NORTHERN ILLINOIS. EXPECT SNOW TO END SHORTLY AFTER MIDNIGHT
IN THE FAR SOUTHEAST CORNER OF THE FORECAST AREA. WILL LIKELY
EXPAND WINTER WEATHER ADVISORY ACROSS THIS AREA THROUGH THE 00Z
TIME FRAME IN LINE WITH EXPECTED SNOW. CURRENT INDICATIONS ARE FOR
1 TO 3 INCH ACCUMULATIONS BY EVENING IN THE ADVISORY AREA WITH AN
INCH OR LESS ELSEWHERE THROUGH THE EVENING.
WILL ALSO EXPAND WIND ADVISORY ACROSS REMAINDER OF SOUTHEAST
NEBRASKA AND SOUTHWEST IOWA AND EXTEND THROUGH 03Z.
WEATHER CONDITIONS IMPROVE FOR THE AREA AFTER TONIGHT ALTHOUGH
TEMPERATURES WILL BE ON THE COOL SIDE MONDAY. ANOTHER CLIPPER
MOVES INTO THE NORTHERN PLAINS TUESDAY WITH WARMER AIR RETURNING
TO THE AREA IN ADVANCE OF THIS SYSTEM. COLD FRONT THEN MOVES SOUTH
INTO THE AREA ON WEDNESDAY WITH ANOTHER CHANCE OF RAIN OR SNOW.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 220 PM CDT SUN APR 13 2014
COOL AND WET START TO THE EXTENDED PERIOD AS PREVIOUSLY MENTIONED
COLD FRONT MOVES SOUTH OF THE AREA WITH ANOTHER COLD UPPER TROUGH
DEVELOPING OVER THE CENTRAL PART OF THE COUNTRY. DAY TO DAY
WARMING FOLLOWS THIS SYSTEM FOR FRIDAY THROUGH SUNDAY
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 646 PM CDT SUN APR 13 2014
AREAS OF LIGHT SNOW AND A MIX OF LIGHT RAIN AND SNOW WILL
OCCASIONALLY DROP CIGS TO NEAR FL010 AND VSBYS BETWEEN 1SM AND 2SM
IN THE KLNK AND KOMA THROUGH THE 04Z TO 06Z TIMEFRAME. THAT
PRECIPITATION AND CIGS WILL BE MOVING EAST OF THE AREA NEAR AND
AFTER 06Z...WITH IMPROVING CONDITIONS THEREAFTER. EXPECT VFR
CONDITIONS AT ALL SITES AFTER 08Z. STRONG NORTH WINDS OF 20 TO
35KT WILL PERSIST THROUGH ABOUT 02Z THEN DECREASE INTO THE 15 TO
25KT RANGE. EXPECT THOSE WINDS TO PERSIST THROUGH MONDAY AFTERNOON
BEFORE BEGINNING TO DIMINISH.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...DERGAN
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...DERGAN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
147 AM EDT MON APR 14 2014
.SYNOPSIS...
MILD AND DRY THROUGH MOST OF MONDAY. MEANWHILE...LOW PRESSURE
OVER THE CENTRAL U.S. WILL MOVE NORTHEAST AND BRING SHOWERS TO
AREA LATER MONDAY INTO MONDAY NIGHT. ON TUESDAY...A STRONG COLD
FRONT WILL PASS THROUGH. LOCALLY HEAVY RAIN WILL BE POSSIBLE AHEAD
OF THE COLD FRONT...WITH THE POTENTIAL FOR ACCUMULATING SNOWS
BEHIND IT ACROSS CENTRAL NEW YORK. HIGH PRESSURE WILL BRING A
RETURN TO FAIR WEATHER ON WEDNESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
1 AM UPDATE...
AREA RMNS IN WM SECTOR TONIGHT WITH SRLY FLOW DRAWING IN WRMR AIR.
TEMPS ARE STRUGGLING TO DROP OFF ACRS THE SRN TIER AS THEY REMAIN
IN THE MID/UPR 60S. EXPECT THESE TEMPS WL ONLY DROP SVRL MORE
DEGREES THRU DAYBREAK EXCEPT IN DECOUPLED VLY LOCALES, THUS HV
WARMED LOWS INTO THE LWR 60S MOST LOCATIONS FOR OVRNGT MINS. NO
OTHER CHGS NEEDED AT THIS TIME.
PREV DISCUSSIONS BLO...
1015 PM UPDATE...
ELEVATED CONVECTION IS OCCURRING NORTH OF THE SURFACE BOUNDARY
AROUND THE SAINT LAWRENCE SEAWAY...SO AS EXPECTED WE ARE STAYING
DRY TONIGHT. WINDS HAVE QUICKLY DECOUPLED AND SOME GRADUAL DROP OFF
IN TEMPERATURES IS OCCURRING. VERY MILD REGARDLESS...WITH LOWS
EXPECTED TO RANGE FROM THE MID 50S TO NEAR 60.
WITH A GOOD AMOUNT OF SUNSHINE EARLIER...SINCE THE HIGH THIN CLOUDS
ERADICATED MORE THAN EXPECTED...THE LOW 20S CELSIUS TEMPERATURES
AT 925MB /AS HAD BEEN SUGGESTED BY RUC MODEL/ WERE ABLE TO FULLY
REALIZE THEIR MIX-DOWN TEMPERATURES OF LOW 80S IN MANY
LOCATIONS...THE WARMEST READINGS IN 6 MONTHS. BINGHAMTON AIRPORT
DAILY RECORD HIGH IS 80 DEGREES SET IN 1977...AND IT TURNED OUT
JUST 1 DEGREE SHORT OF IT TODAY. SYRACUSE AND AVOCA ALSO JUST A
FEW DEGREES SHY OF DAILY RECORDS.
PREVIOUS DISCUSSION...
VERY MILD TEMPS TDA WITH WARM SWLY FLOW. MAY SEE AN ISOLATED -SHRA
ACRS NRN ONEIDA LATE TDA OR THIS EVNG OTRW A DRY FCST. VERY MILD
MINS TNGT.
NXT SYSTEM APRCHS TMRW. A FEW MDLS HINT AT SOME CONVECTION ALONG A
PRE-FNTL TROF OVER CNTRL NY ARND MID DAY. IN ANY EVENT...INCRSNG
CHCS FOR SHRA TMRW AFTN WITH MAXES GETTING BACK INTO THE 70S MOST
AREAS. TEMPS MAY FALL DURING THE AFTN WRN ZONES AS CLDS AND SCT
-SHRA MOVE IN. GUSTY SSW WINDS CONTINUE ON MON.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
VERY COMPLEX STORM SYSTEM WITH SHARP BAROCLINIC ZONE/ANAFRONT
MOVS THRU ON TUE WITH WEAK SFC WAVES RIDING NE ALONG IT.
TIMING OF THIS FNT ON TUE WILL BE CRITICAL TO THE FCST
W/RESPECT TO CHGOVER AND +RA POTNL IN THE EAST. IN GNRL 12Z RUNS
ARE SUGGESTING THAT THE TRANSITION ZONE IS BASICALLY THRU THE CWA
BY 00Z WED...AND NAM/GFS SFC INDICATE RAPIDLY FALLING SNOW LVLS WITH THE
FNT ON TUE.
BOTTOM LINE IS THAT THERE IS ALOT OF UNCERTAINTY WITH THIS
STORM...BUT TREND HAS BEEN FOR A SLIGHTLY QUICKER TIMING. WE COULD
SEE PL IN THE TRANSITION ZONE BUT FOR NOW WILL JUST PLAY IT AS RAIN
CHANGING TO SNOW. GIVEN A COUPLE OF VERY WARM DAYS THINK ICE POTNL
FROM NAM PROFILES IS OVERDONE. WE DID LIKE THE WWD SNOW ACCUMS
WITH POTNL FOR GNRLY 2-4 INCHES ON TUE AFTN/EVNG ACRS PORTIONS OF
CNTRL NY.
MAYBE A FEW FLURRIES SE OF LAKE ONTARIO ON TUE NGT...WITH LAKE
CLDS LIKELY SE OF LAKE ONTARIO ON WED MRNG IN NWLY FLOW. MUCH
COOLER WITH MAXES ONLY U30S TO L40S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
MEDIUM RANGE MODELS START OUT IN GOOD AGREEMENT EARLY IN THE
EXTENDED PERIOD THEN DIVERGE BY NEXT WEEKEND.
INITIALLY SFC HIGH PRES OVER NRN NEW ENGLAND AND NOVA SCOTIA WILL
BRING FAIR AND COOL WEATHER TO THE AREA WITH LOWS WED NIGHT IN THE
MID TO UPPER 20S FOLLOWED BY UPPER 20S TO MID 30S ON THURSDAY
NIGHT. MAXES BOTH THURSDAY AND FRIDAY WILL RANGE IN THE 50S WITH
SOME MODIFICATION ON FRIDAY.
FRIDAY NIGHT THROUGH SUNDAY THE OPERATIONAL GFS TAKES A SFC LOW
IN THE TN VALLEY AND TRACKS IT NORTHEAST ACROSS OUR VCNTY THEN INTO
EASTERN CANADA BY SUNDAY. A WET SCENARIO FOLLOWED BY WRAP AROUND
MOISTURE SATURDAY NIGHT INTO SUNDAY. THE ECMWF PLACES THIS FEATURE
FARTHER SOUTH AND WEAKER THEN MOVES IT OFF THE MID ATLANTIC COAST
KEEPING THE REGION BASICALLY DRY. FOLLOWED HPC GUIDANCE WHICH
KEEPS THE SYSTEM TO OUR SOUTH BUT WILL INCLUDE CHC POPS FROM
FRIDAY NIGHT THROUGH SATURDAY NIGHT FOR RAIN SHOWERS.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS EXPECTED THROUGH THE MAJORITY OF THE FCST PERIOD
AS STRONG SOUTHWEST FLOW PREVAILS AHEAD OF AN APPROACHING COLD
FRONT. WINDS WILL AGAIN INCREASE AFTER SUNRISE WITH SOLID GUSTS TO
NEAR/SLIGHTLY ABOVE 25 KTS THROUGH THE DAY TODAY. BEFORE THIS
HOWEVER...STRONG WINDS OFF THE DECK WILL LEAD TO LOW-LEVEL WIND
SHEAR AT ALL SITES UNTIL MIXING COMMENCES AFTER SUNRISE. IN TERMS OF
PRECIP CHANGES...BEST POTENTIAL EXISTS AT SYR/RME/ITH/ELM AFTER 21
OR SO...WITH BEST ORGANIZED RAIN POTENTIAL HOLDING OFF UNTIL AFTER
00Z AT ALL CNY SITES. DRY CONDITIONS ANTICIPATED AT AVP THROUGH THE
FCST PERIOD. AT ITH AND BGM...EXPECT DEVELOPING MVFR CIGS AFTER
00Z AS FRONTAL BOUNDARY APPROACHES.
OUTLOOK...
TUE...RESTRICTIONS IN SCATTERED RAIN SHOWERS AND ISOLATED THUNDER
TUESDAY MORNING...WITH RAIN CHANGING TO SNOW TUE AFTERNOON/EVENING.
TUE NGT...RESTRICTIONS POSSIBLE IN SCATTERED SNOW SHOWERS.
WED-THU-FRI...VFR.
&&
.FIRE WEATHER...
1015 PM SUNDAY UPDATE...
CONDITIONS APPROACHED CRITICAL VALUES SUNDAY AFTERNOON BUT WINDS
HAVE BACKED OFF CONSIDERABLY THIS EVENING ALONG WITH RECOVERING
RELATIVE HUMIDITY ALREADY IN THE 40S-50S PCT RANGE AT 10 PM.
FAIRLY WARM WITH STOUT SOUTH-SOUTHWEST WINDS AGAIN MONDAY...BUT
WITH HIGHER HUMIDITY VALUES AS MOISTURE INCREASES AHEAD OF
APPROACHING COLD FRONT. MINIMUM HUMIDITY VALUES MONDAY...VERSUS
WHAT WE JUST HAD SUNDAY AFTERNOON...WILL BE A GOOD 15 TO 25
PERCENT HIGHER. RAIN CHANCES INCREASING LATE MONDAY THROUGH MONDAY
NIGHT...LEADING TO A SOLID WETTING RAIN TUESDAY WITH FALLING
TEMPERATURES. EVEN SOME CHANGEOVER TO SNOW TUESDAY AFTERNOON-
EVENING /ESPECIALLY CENTRAL NY/.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP/PVN
SHORT TERM...
LONG TERM...RRM
AVIATION...CMG
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
105 AM EDT MON APR 14 2014
.SYNOPSIS...
MILD AND DRY THROUGH MOST OF MONDAY. MEANWHILE...LOW PRESSURE
OVER THE CENTRAL U.S. WILL MOVE NORTHEAST AND BRING SHOWERS TO
AREA LATER MONDAY INTO MONDAY NIGHT. ON TUESDAY...A STRONG COLD
FRONT WILL PASS THROUGH. LOCALLY HEAVY RAIN WILL BE POSSIBLE AHEAD
OF THE COLD FRONT...WITH THE POTENTIAL FOR ACCUMULATING SNOWS
BEHIND IT ACROSS CENTRAL NEW YORK. HIGH PRESSURE WILL BRING A
RETURN TO FAIR WEATHER ON WEDNESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
1 AM UPDATE...
AREA RMNS IN WM SECTOR TONIGHT WITH SRLY FLOW DRAWING IN WRMR AIR.
TEMPS ARE STRUGGLING TO DROP OFF ACRS THE SRN TIER AS THEY REMAIN
IN THE MID/UPR 60S. EXPECT THESE TEMPS WL ONLY DROP SVRL MORE
DEGREES THRU DAYBREAK EXCEPT IN DECOUPLED VLY LOCALES, THUS HV
WARMED LOWS INTO THE LWR 60S MOST LOCATIONS FOR OVRNGT MINS. NO
OTHER CHGS NEEDED AT THIS TIME.
PREV DISCUSSIONS BLO...
1015 PM UPDATE...
ELEVATED CONVECTION IS OCCURRING NORTH OF THE SURFACE BOUNDARY
AROUND THE SAINT LAWRENCE SEAWAY...SO AS EXPECTED WE ARE STAYING
DRY TONIGHT. WINDS HAVE QUICKLY DECOUPLED AND SOME GRADUAL DROP OFF
IN TEMPERATURES IS OCCURRING. VERY MILD REGARDLESS...WITH LOWS
EXPECTED TO RANGE FROM THE MID 50S TO NEAR 60.
WITH A GOOD AMOUNT OF SUNSHINE EARLIER...SINCE THE HIGH THIN CLOUDS
ERADICATED MORE THAN EXPECTED...THE LOW 20S CELSIUS TEMPERATURES
AT 925MB /AS HAD BEEN SUGGESTED BY RUC MODEL/ WERE ABLE TO FULLY
REALIZE THEIR MIX-DOWN TEMPERATURES OF LOW 80S IN MANY
LOCATIONS...THE WARMEST READINGS IN 6 MONTHS. BINGHAMTON AIRPORT
DAILY RECORD HIGH IS 80 DEGREES SET IN 1977...AND IT TURNED OUT
JUST 1 DEGREE SHORT OF IT TODAY. SYRACUSE AND AVOCA ALSO JUST A
FEW DEGREES SHY OF DAILY RECORDS.
PREVIOUS DISCUSSION...
VERY MILD TEMPS TDA WITH WARM SWLY FLOW. MAY SEE AN ISOLATED -SHRA
ACRS NRN ONEIDA LATE TDA OR THIS EVNG OTRW A DRY FCST. VERY MILD
MINS TNGT.
NXT SYSTEM APRCHS TMRW. A FEW MDLS HINT AT SOME CONVECTION ALONG A
PRE-FNTL TROF OVER CNTRL NY ARND MID DAY. IN ANY EVENT...INCRSNG
CHCS FOR SHRA TMRW AFTN WITH MAXES GETTING BACK INTO THE 70S MOST
AREAS. TEMPS MAY FALL DURING THE AFTN WRN ZONES AS CLDS AND SCT
-SHRA MOVE IN. GUSTY SSW WINDS CONTINUE ON MON.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
VERY COMPLEX STORM SYSTEM WITH SHARP BAROCLINIC ZONE/ANAFRONT
MOVS THRU ON TUE WITH WEAK SFC WAVES RIDING NE ALONG IT.
TIMING OF THIS FNT ON TUE WILL BE CRITICAL TO THE FCST
W/RESPECT TO CHGOVER AND +RA POTNL IN THE EAST. IN GNRL 12Z RUNS
ARE SUGGESTING THAT THE TRANSITION ZONE IS BASICALLY THRU THE CWA
BY 00Z WED...AND NAM/GFS SFC INDICATE RAPIDLY FALLING SNOW LVLS WITH THE
FNT ON TUE.
BOTTOM LINE IS THAT THERE IS ALOT OF UNCERTAINTY WITH THIS
STORM...BUT TREND HAS BEEN FOR A SLIGHTLY QUICKER TIMING. WE COULD
SEE PL IN THE TRANSITION ZONE BUT FOR NOW WILL JUST PLAY IT AS RAIN
CHANGING TO SNOW. GIVEN A COUPLE OF VERY WARM DAYS THINK ICE POTNL
FROM NAM PROFILES IS OVERDONE. WE DID LIKE THE WWD SNOW ACCUMS
WITH POTNL FOR GNRLY 2-4 INCHES ON TUE AFTN/EVNG ACRS PORTIONS OF
CNTRL NY.
MAYBE A FEW FLURRIES SE OF LAKE ONTARIO ON TUE NGT...WITH LAKE
CLDS LIKELY SE OF LAKE ONTARIO ON WED MRNG IN NWLY FLOW. MUCH
COOLER WITH MAXES ONLY U30S TO L40S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
MEDIUM RANGE MODELS START OUT IN GOOD AGREEMENT EARLY IN THE
EXTENDED PERIOD THEN DIVERGE BY NEXT WEEKEND.
INITIALLY SFC HIGH PRES OVER NRN NEW ENGLAND AND NOVA SCOTIA WILL
BRING FAIR AND COOL WEATHER TO THE AREA WITH LOWS WED NIGHT IN THE
MID TO UPPER 20S FOLLOWED BY UPPER 20S TO MID 30S ON THURSDAY
NIGHT. MAXES BOTH THURSDAY AND FRIDAY WILL RANGE IN THE 50S WITH
SOME MODIFICATION ON FRIDAY.
FRIDAY NIGHT THROUGH SUNDAY THE OPERATIONAL GFS TAKES A SFC LOW
IN THE TN VALLEY AND TRACKS IT NORTHEAST ACROSS OUR VCNTY THEN INTO
EASTERN CANADA BY SUNDAY. A WET SCENARIO FOLLOWED BY WRAP AROUND
MOISTURE SATURDAY NIGHT INTO SUNDAY. THE ECMWF PLACES THIS FEATURE
FARTHER SOUTH AND WEAKER THEN MOVES IT OFF THE MID ATLANTIC COAST
KEEPING THE REGION BASICALLY DRY. FOLLOWED HPC GUIDANCE WHICH
KEEPS THE SYSTEM TO OUR SOUTH BUT WILL INCLUDE CHC POPS FROM
FRIDAY NIGHT THROUGH SATURDAY NIGHT FOR RAIN SHOWERS.
&&
.AVIATION /05Z MONDAY THROUGH FRIDAY/...
00Z UPDATE...
VFR CONDITIONS GENERALLY EXPECTED THROUGH 00Z TUESDAY...BUT
SCATTERED SHOWERS AND PERHAPS ISOLATED THUNDERSTORMS COULD BE
MOVING INTO THE WESTERN TERMINALS /KSYR-KITH-KELM AND MAYBE KRME/
21Z MON-00Z TUE. THIS WILL BE WITH INCREASING MOISTURE AND
INSTABILITY AHEAD OF AN APPROACHING COLD FRONT...WHICH WILL NOT
PASS UNTIL TUESDAY. WINDS DECOUPLING AND DIMINISHING THIS EVENING NEAR
THE SURFACE...YET STILL STRONG FROM THE SSW AS A 40-50 KT JET
DEVELOPS AT 1500-2000 FT AGL...RESULTING IN LLWS CONDITIONS
OVERNIGHT. LLWS THEN BECOMES A NON-ISSUE SHORTLY AFTER 12Z AS WINDS
MANAGE TO MIX DOWN BETTER TO THE SURFACE WITH DAYTIME HEATING.
DURING THE DAY MONDAY...SURFACE WIND SUSTAINED MID TEENS WITH
GUSTS IN 25-30 KT RANGE...FROM SSW DIRECTION.
OUTLOOK...
MON NGT-TUE...RESTRICTIONS IN SCATTERED RAIN SHOWERS AND ISOLATED
THUNDER MONDAY NIGHT TO TUESDAY MORNING...THEN RAIN CHANGING TO
SNOW TUE AFTERNOON-EVENING.
TUE NGT...RESTRICTIONS POSSIBLE IN SCATTERED SNOW SHOWERS.
WED-THU-FRI...VFR.
&&
.FIRE WEATHER...
1015 PM SUNDAY UPDATE...
CONDITIONS APPROACHED CRITICAL VALUES SUNDAY AFTERNOON BUT WINDS
HAVE BACKED OFF CONSIDERABLY THIS EVENING ALONG WITH RECOVERING
RELATIVE HUMIDITY ALREADY IN THE 40S-50S PCT RANGE AT 10 PM.
FAIRLY WARM WITH STOUT SOUTH-SOUTHWEST WINDS AGAIN MONDAY...BUT
WITH HIGHER HUMIDITY VALUES AS MOISTURE INCREASES AHEAD OF
APPROACHING COLD FRONT. MINIMUM HUMIDITY VALUES MONDAY...VERSUS
WHAT WE JUST HAD SUNDAY AFTERNOON...WILL BE A GOOD 15 TO 25
PERCENT HIGHER. RAIN CHANCES INCREASING LATE MONDAY THROUGH MONDAY
NIGHT...LEADING TO A SOLID WETTING RAIN TUESDAY WITH FALLING
TEMPERATURES. EVEN SOME CHANGEOVER TO SNOW TUESDAY AFTERNOON-
EVENING /ESPECIALLY CENTRAL NY/.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP/PVN
SHORT TERM...
LONG TERM...RRM
AVIATION...MDP
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
336 AM EDT MON APR 14 2014
.SYNOPSIS...
STRONG COLD FRONT MONDAY NIGHT. HIGH PRESSURE REST OF THE WORK
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
00Z RUN OF THE NAM CAME OUT WITH A DISTINGUISHED LINE OF CONVECTION
WELL AHEAD OF THE COLD FRONT AND THE MID AND UPPER LEVEL TROUGH
AXES. GFS CAME IN SUPPORTING THE SAME FEATURE...WITH THE HRRR IN
LINE AS WELL AS THE LINE COMES INTO THE SCOPE OF THAT MODEL/S
FORECAST RANGE. THIS IS THE ONLY MAJOR CHANGE TO THE FORECAST. SPC
KEEPS THE SLIGHT RISK OF SEVERE WEATHER WELL TO THE SOUTH THANKS TO
LOW DEWPOINTS CONTRIBUTING TO LOW SURFACE BASED CAPE. A DEVELOPING
WAVE ALONG THE FRONT WILL KEEP THE PRECIPITATION CHANCES ENHANCED
THROUGH THE MONDAY NIGHT PERIOD...WITH THE HINTS OF CLEARING COMING
IN THE NORTHWEST ZONES AT 12Z TUESDAY IN THE FORM OF POPS DROPPING
TO CHANCE.
AFTER A VERY WARM MORNING...TEMPERATURES WILL PUSH THE 80F MARK
AGAIN TODAY...COOLER WITHOUT MUCH SUN TO SPEAK OF...BUT STILL WELL
ABOVE NORMAL IN THE WARM SECTOR.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
GOOD MODEL AGREEMENT ON TIMING OF THE STRONG COLD FRONT EXITING THE
MOUNTAINS EARLY TUESDAY MORNING...FOLLOWED BY MOSTLY FALLING
TEMPERATURES DURING THE DAY. POST FRONTAL PRECIPITATION WILL END
FROM WEST TO EAST DURING THE DAY...WITH MODELS ALSO AGREEING ON THE
EXIT TIMING OF THE DEEPER MOISTURE AND PRECIP WITH THE SYSTEM. BY
DAYS END ONLY A SLIGHT CHANCE WILL LINGER IN THE NORTHERN
MOUNTAINS...ENDING BY MIDNIGHT.
THE BIG CHALLENGE IS THE NON DIURNAL TEMPERATURE CURVE DURING
TUESDAY...IN THE VERY STRONG COLD ADVECTION AND UNUSUALLY COLD
AIRMASS FOR THIS TIME OF YEAR...AND THUS THE PROSPECTS OF RAIN TO
SNOW. GIVEN THE COLD MODEL CONSENSUS ALOFT WHICH WOULD SUPPORT A
CHANGEOVER TO SNOW FROM WEST TO EAST TOWARD THE END OF THE
PRECIPITATION...THE ISSUE WILL BE THE BOUNDARY LAYER TEMPERATURES.
MODELS DO SHOW STRONG TEMPERATURE FALLS IN THE MORNING AND TENDING
TO LEVEL OUT FOR A TIME IN THE LOW LANDS IN THE AFTERNOON...BEFORE
FALLING AGAIN TUESDAY NIGHT. THIS IS REASONABLE FOR THIS TIME OF
YEAR...AND ESPECIALLY IN THE WEST AND CENTRAL AS PRECIPITATION ENDS
EARLIER IN THE DAY. WILL GO WITH THE NAM MOS GUIDANCE...MAINLY
BECAUSE IT BEST SHOWS A BREAK IN THE TEMPERATURE FALLS DURING THE
AFTERNOON...ESPECIALLY WEST AND CENTRAL. THUS...BELIEVE ANY
MIX/CHANGEOVER TO SNOW IN THE LOW LANDS WILL BE BRIEF BEFORE THE
PRECIPITATION ENDS WITH NO ACCUMULATIONS...AS SURFACE TEMPERATURES
WILL STILL BE ABOVE FREEZING AND THE GROUND QUITE WARM. IN THE
CENTRAL AND NORTHERN MOUNTAINS...THERE WILL BE A CHANGEOVER TO SNOW
DURING THE AFTERNOON...BUT ACCUMULATIONS WILL LIKELY BE AN INCH OR
LESS AND MOSTLY CONFINED TO THE HIGHER ELEVATIONS. LOOK FOR
TEMPERATURES TO START OUT TUESDAY MORNING IN THE 50S EAST AND NEAR
40 FAR WEST...REACHING BY EVENING THE LOW TO MID 30S MOST OF THE LOW
LANDS AND BELOW FREEZING ABOVE 2000 FEET.
WHILE SNOW SHOWERS TAPER OFF EARLY TUESDAY NIGHT IN THE MOUNTAINS...
CLEARING FOLLOWS MORE SLOWLY WITH THE COLD ADVECTION AND UPSLOPE
FLOW IN THE MOUNTAINS. STILL...IT SHOULD BECOME MOSTLY CLEAR EARLY
ENOUGH AS DRY HIGH PRESSURE BUILDS IN RAPIDLY FROM THE WEST...AND
ALLOW TEMPERATURES TO FALL WELL BELOW FREEZING IN ALL LOCATIONS.
HOWEVER...BELIEVE THE MODELS MAY BE A BIT ON THE LOW SIDE AS THEY
FORECAST A RUN FOR RECORD LOWS TUESDAY NIGHT. FOR NOW...WILL KEEP
OUR MINS A COUPLE OF DEGREES ABOVE THE MOS...BUT STILL WELL BELOW
FREEZING.
THEREAFTER...HIGH PRESSURE SLIDES ACROSS WITH ABUNDANT SUNSHINE
WEDNESDAY AND THURSDAY...ALONG WITH A WARMING TREND. WITH DRY AIR
AND LIGHT WINDS WEDNESDAY NIGHT...TEMPERATURES COULD FALL BELOW
FREEZING AGAIN.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
SW FLOW DOMINATES THROUGH FRIDAY BEFORE S/W TROF TRIES TO CREATE FOR
AN UNSETTLED SATURDAY. DUE TO CONTINUED DIFFERENCES REGARDING
AMPLITUDE AND STRENGTH OF SURFACE FEATURES...HAVE STAYED CLOSE TO
WPC PREFERRED SOLUTION WITH THREAT FOR SHRA FRIDAY NIGHT AND
SATURDAY.
FOR TEMPS...A WARMING TREND WILL BE NOTED TO ROUND OUT THE WORK
WEEK...BEFORE COOLER BUT MORE SEASONAL AIR ARRIVES FOR THE WEEKEND.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
VFR EXPECTED AHEAD OF THE CONVECTION ASSOCIATED WITH A STRONG
FRONTAL SYSTEM.
CEILINGS WILL GRADUALLY LOWER...WITH CONVECTION ENTERING THE
WESTERN TERMINALS AT AROUND 17Z-18Z. PREFERRING MVFR CONDITIONS TO
PREVAIL WITH VCTS FOR NOW GIVEN THE ATMOSPHERIC SET UP. EXPECTING
SOUTHERLY WINDS IN THE WARM SECTOR WHICH WILL TYPICALLY LEND TO
HIGHER CEILINGS...EVEN IN SHRA/TSRA. TEMPOS WILL LIKELY BE NEEDED
FOR BRIEF IFR VISIBILITIES. WILL REEVALUATE THE PREVAILING TSRA
POTENTIAL FOR THE 12Z TAF ISSUANCE.
SPEAKING OF VISIBILITIES...NOT EXPECTING BR/FG TO SETTLE IN
BETWEEN ROUNDS OF SHRA/TSRA GIVEN THE STRONG GRADIENT WIND SET UP.
MAY GET SOME GUSTS WITH THE CONVECTION...ALSO NECESSITATING TEMPOS
AS WELL.
COLD FRONT SHOULD NOT PASS BEFORE 06Z TUESDAY...SO WILL NOT SEE
THE WIND DIRECTION SHIFT IN THIS PERIOD.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY...
FORECAST CONFIDENCE: HIGH THROUGH 18Z. MEDIUM AFTER.
ALTERNATE SCENARIOS: CONVECTION TIMING AND BRIEF FLIGHT CATEGORY
BOUNCES COULD LEAD TO TEMPOS AND AMENDMENTS. MAY NEED PREVAILING
TSRA.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE MON 04/14/14
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EDT 1HRLY 04 05 06 07 08 09 10 11 12 13 14 15
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z TUESDAY...
IFR CONDITIONS EXPECTED LATE MONDAY NIGHT UNDER MODERATE RAIN
SHOWERS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/26
NEAR TERM...26
SHORT TERM...JMV
LONG TERM...30
AVIATION...26
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
542 AM EDT MON APR 14 2014
.SYNOPSIS...
AFTER ANOTHER MILD DAY...A FRONTAL SYSTEM WILL APPROACH THE AREA
TONIGHT...AND PASS THROUGH THE REGION TUESDAY. BELOW NORMAL
TEMPERATURES WILL FOLLOW THE FRONT AND LAST THROUGH MID-
WEEK...WITH A GRADUAL MODERATION TOWARD THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
SATELLITE SHOWS PLENTY OF MID AND HIGH CLOUDS STREAMING NE OVER
THE AREA...ESPECIALLY WESTERN LOCATIONS.
IT WILL BE ANOTHER VERY MILD DAY...BUT WITH MORE IN THE WAY OF
CLOUDINESS...WE SHOULD KNOCK A FEW DEGREES OFF YESTERDAY`S HIGHS
IN MOST AREAS.
THE DEEPER WE GET INTO THE DAY THE BETTER THE CHANCE WILL BE FOR
A STRAY SHOWER OR EVEN A THUNDERSTORM. THE OPERATIONAL MODELS ALL
SPLASH AROUND A FAIR AMOUNT OF LIGHT QPF THIS AFTERNOON...AND THE
SREF/GEFS EVEN SHOW A DECENT CHANCE OF MEASURABLEPRECIP...THOUGH
THE PROBABILITIES OF MORE THAN ABOUT A TENTH ARE PRETTY SMALL. THE
HIGH RES NMM/ARW AND HRRR ALL KEEP THE BULK OF THE FCST AREA
MAINLY DRY THROUGH AT LEAST 20Z. THEY ALSO AGREE ON GENERATING A
LINE OF CONVECTION WHICH SHOULD BE ENTERING MY WESTERN ZONES BY
AROUND NIGHTFALL. SPC DOES NOT OUTLOOK US FOR SEVERE AND
INSTABILITY WILL BE LIMITED...BUT WITH STRONG WINDS ALOFT...I
WOULDN`T BE SURPRISED TO SEE A FEW THUNDERSTORMS ACCOMPANIED BY
GUSTY WINDS INTO THE EVENING HOURS.
THE TIMING OF THE CONVECTION INDICATED BY THE HIGH RES MODELS
WOULD SUGGEST THAT THE SHOWERS WILL TEND TO RUN OUT OF GAS AS THEY
HEAD EAST AFTER THE SUN GOING DOWN. REGARDLESS WE WILL SEE
OCCASIONALRAIN AND SHOWERS CONTINUE INTO TUESDAY. THE TIGHT
TEMPERATURE GRADIENT ASSOCIATED WITH THE FRONT MEANS THERE WILL BE
A BIG BUST POTENTIAL FOR THE OVERNIGHT LOW. IF THE FRONT IS
FAST...LOWS OVER THE NW COULD BE MUCH COOLER THAN I CURRENTLY
PORTRAY.
&&
.SHORT TERM /TUESDAY/...
THE FRONT WILL MOVE ACROSS THE AREA TUESDAY...ALONG WITH THE SAME
BIG TEMP BUST POTENTIAL OF TONIGHT. MODEL THERMAL FIELDS SHOW A
VERY TIGHT PACKING OF THE COLD AIR JUST BEHIND THE FRONT SO SMALL
TIMING PROBLEMS WILL MEAN RELATIVELY BIG TEMP SWINGS AS THE SYSTEM
SLIDES EAST.
A COUPLE OF OTHER CONCERNS FOR TUESDAY INCLUDE THE POTENTIAL FOR A
NARROW COLD FRONTAL RAINBAND TO FORM...AS WELL AS HOW MUCH IF ANY
SNOW MANAGES TO ACCUMULATE ON THE COLD AIR SIDE OF THE WAVY COLD
FRONT.
AS THE UPPER TROUGH TAKES ON A NEGATIVE TILT AND SWINGS
THROUGH...WE HAVE SEEN IN THE PAST THESE FRONTS TAKE ON STRONG
ANAFRONT CHARACTERISTICS INCLUDING A NARROW LINE OF CONVECTION AND
LOCALIZED STRONG GUSTY WINDS AS PROGGED 850-500MB WINDS ON THE
ORDER OF 45-60KT MIX DOWN IN SOME OF THE STRONGER CONVECTION.
THEN THE...SNOW...YUK! COLD AIR MOVING INTO THE AREA BEHIND THE
FRONT SHOULD CAUSE RAIN TO MIX WITH/CHANGEOVER TO WET SNOW ACROSS
THE WESTERN AND CENTRAL MOUNTAINS TUESDAY INTO TUESDAY NIGHT. AT
THIS TIME...I AM THINKING THAT THE PRECIP WILL BE WINDING DOWN
RATHER QUICKLY TUESDAY AFTERNOON INTO THE EVENING...MEANING THE
CHANGE- OVER WILL BE OCCURRING DURING THE DAY FOR THE MOST PART
WHICH IS USUALLY VITAL AT THIS TIME OF THE YEAR. STILL CAN`T RULE
OUT A COATING TO A COUPLE OF SLUSHY INCHES OF SNOW...WHICH COULD
RESULT IN HAZARDOUS TRAVEL AND ROAD CONDITIONS. THE BEST CHANCE
FOR A FEW INCHES OF WET SNOW WILL BE OVER THE HIGHEST ELEVATIONS
IN THE WESTERN ALLEGHENIES. NO HEADLINES ARE PLANNED AT THIS
POINT...BUT THE POTENTIAL HAS BEEN ADDRESSED IN OUR HWO.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
GROWING SEASON TECHNICALLY STARTS TUESDAY OVER MY SERN ZONES.
AFTER SOME COORDINATION WITH SURROUNDING OFFICES...HAVE AGREED TO
LEAN AWAY FROM ANY FROST/FREEZE HEADLINES...BUT THE LOWS WILL
LIKELY SUPPORT A FREEZE WATCH/WARNING BEING ISSUED AT SOME POINT
TODAY.
THE LAST OF THE SHOWERS WILL BE LEAVING THE REGION TUESDAY
EVENING LEADING THE WAY TO A FEW FAIR BUT ABNORMALLY CHILLY DAYS
FROM WEDNESDAY INTO THE END OF THE WEEK. RISING HEIGHTS/SW FLOW
ALOFT OVER THE EASTERN US IN RESPONSE TO FCST TROUGHING OVER THE
N-CENTRAL PLAINS SHOULD ALLOW FOR TEMPERATURES TO REBOUND TOWARD
THE WEEKEND.
&&
.AVIATION /10Z MONDAY THROUGH FRIDAY/...
STILL BREEZY IN SPOTS AS OF 5 AM.
HAVE LLWS IN ALL SITES FOR THIS MORNING.
MAINLY VFR TODAY. TOOK OUT LOWER CIGS AT LNS AND MDT
EARLIER...GIVEN FLOW IS MORE SW INSTEAD OF SE. ALSO
DEWPOINTS NOT REAL HIGH. BULK OF THE RAIN WILL BE AFTER
SUNSET TODAY.
NO BIG CHANGES MADE TO 09Z TAFS.
EARLIER DISCUSSION BELOW.
VFR CONDITIONS CONTINUE AT ALL LOCATION TONIGHT. WHILE THESE
CONDITIONS WILL PRETTY MUCH PREVAIL MOST OF THE OVERNIGHT AND
MONDAY...SOME MVFR CONDITIONS ARE EXPECTED LATE TONIGHT OVER THE
LOWER SUSQUEHANNA AIRFIELDS OF KMDT AND KLNS. THERE MAY BE SOME
OTHER PATCHY AREAS OF FOG AROUND OVERNIGHT AS WELL IN OTHER
LOCATIONS...BUT AT THIS POINT SEEMS PATCHY ENOUGH NOT TO INCLUDE
IN OTHER TAFS.
ADDITIONALLY...LLWS CONDITIONS CONTINUE OVER CENTRAL AND EASTERN
TAFS TONIGHT AS SURFACE WINDS DECOUPLE...GENERALLY REDUCING TO
UNDER 10 KNOTS. SHORT RANGE MODELS CONTINUE TO SHOW A HEALTHY LOW
LEVEL JET OF 35 TO 45 KNOTS FROM THE WSW OVERNIGHT. IN WESTERN
AREAS...UPPER FLOW IS LIGHTER...MAINLY 20 KNOTS OR SO. THEREFORE
DID NOT INCLUDE LLWS IN KJST AND KBFD.
WHILE SHOWERS AND THUNDERSTORMS SHOULD BE APPROACHING FROM THE
WEST TOMORROW...HAVE SLOWED THE ONSET OF LOWER CIGS AND VSBYS
UNTIL AFTER 00Z. DID INTRODUCE VCSH TO WESTERN AIRFIELDS...AND
WILL HAVE TO WATCH THE PROGRESSION OF PRECIPITATION TOMORROW.
THERE IS A RISK THAT SOME RESTRICTIONS MAY WORK INTO KBFD SHORTLY
BEFORE 00Z.
CONDITIONS ACROSS THE REGION WILL DETERIORATE LATER MONDAY INTO
TUESDAY WITH IFR CIGS AND REDUCED VSBY WITH PRECIPITATION MOVING
IN. CONVECTIVE CELLS ARE POSSIBLE WITH THE COLD FRONT.
OUTLOOK...
.MON...MAINLY VFR...WITH LOWERING CLOUDS. RESTRICTIONS POSSIBLE
IN THE WEST CLOSE TO 00Z.
.MON NIGHT-TUE...RAIN/REDUCED CIGS POSSIBLE...POSSIBLY ENDING AS
A BRIEF PERIOD OF WET SNOW ACROSS THE NORTHERN AND WESTERN MTNS.
.WED-THU...VFR.
.FRI...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...JUNG/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
457 AM EDT MON APR 14 2014
.SYNOPSIS...
AFTER ANOTHER MILD DAY...A FRONTAL SYSTEM WILL APPROACH THE AREA
TONIGHT...AND PASS THROUGH THE REGION TUESDAY. BELOW NORMAL
TEMPERATURES WILL FOLLOW THE FRONT AND LAST THROUGH MID-
WEEK...WITH A GRADUAL MODERATION TOWARD THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
SATELLITE SHOWS PLENTY OF MID AND HIGH CLOUDS STREAMING NE OVER
THE AREA...ESPECIALLY WESTERN LOCATIONS.
IT WILL BE ANOTHER VERY MILD DAY...BUT WITH MORE IN THE WAY OF
CLOUDINESS...WE SHOULD KNOCK A FEW DEGREES OFF YESTERDAY`S HIGHS
IN MOST AREAS.
THE DEEPER WE GET INTO THE DAY THE BETTER THE CHANCE WILL BE FOR
A STRAY SHOWER OR EVEN A THUNDERSTORM. THE OPERATIONAL MODELS ALL
SPLASH AROUND A FAIR AMOUNT OF LIGHT QPF THIS AFTERNOON...AND THE
SREF/GEFS EVEN SHOW A DECENT CHANCE OF MEASURABLEPRECIP...THOUGH
THE PROBABILITIES OF MORE THAN ABOUT A TENTH ARE PRETTY SMALL. THE
HIGH RES NMM/ARW AND HRRR ALL KEEP THE BULK OF THE FCST AREA
MAINLY DRY THROUGH AT LEAST 20Z. THEY ALSO AGREE ON GENERATING A
LINE OF CONVECTION WHICH SHOULD BE ENTERING MY WESTERN ZONES BY
AROUND NIGHTFALL. SPC DOES NOT OUTLOOK US FOR SEVERE AND
INSTABILITY WILL BE LIMITED...BUT WITH STRONG WINDS ALOFT...I
WOULDN`T BE SURPRISED TO SEE A FEW THUNDERSTORMS ACCOMPANIED BY
GUSTY WINDS INTO THE EVENING HOURS.
THE TIMING OF THE CONVECTION INDICATED BY THE HIGH RES MODELS
WOULD SUGGEST THAT THE SHOWERS WILL TEND TO RUN OUT OF GAS AS THEY
HEAD EAST AFTER THE SUN GOING DOWN. REGARDLESS WE WILL SEE
OCCASIONALRAIN AND SHOWERS CONTINUE INTO TUESDAY. THE TIGHT
TEMPERATURE GRADIENT ASSOCIATED WITH THE FRONT MEANS THERE WILL BE
A BIG BUST POTENTIAL FOR THE OVERNIGHT LOW. IF THE FRONT IS
FAST...LOWS OVER THE NW COULD BE MUCH COOLER THAN I CURRENTLY
PORTRAY.
&&
.SHORT TERM /TUESDAY/...
THE FRONT WILL MOVE ACROSS THE AREA TUESDAY...ALONG WITH THE SAME
BIG TEMP BUST POTENTIAL OF TONIGHT. MODEL THERMAL FIELDS SHOW A
VERY TIGHT PACKING OF THE COLD AIR JUST BEHIND THE FRONT SO SMALL
TIMING PROBLEMS WILL MEAN RELATIVELY BIG TEMP SWINGS AS THE SYSTEM
SLIDES EAST.
A COUPLE OF OTHER CONCERNS FOR TUESDAY INCLUDE THE POTENTIAL FOR A
NARROW COLD FRONTAL RAINBAND TO FORM...AS WELL AS HOW MUCH IF ANY
SNOW MANAGES TO ACCUMULATE ON THE COLD AIR SIDE OF THE WAVY COLD
FRONT.
AS THE UPPER TROUGH TAKES ON A NEGATIVE TILT AND SWINGS
THROUGH...WE HAVE SEEN IN THE PAST THESE FRONTS TAKE ON STRONG
ANAFRONT CHARACTERISTICS INCLUDING A NARROW LINE OF CONVECTION AND
LOCALIZED STRONG GUSTY WINDS AS PROGGED 850-500MB WINDS ON THE
ORDER OF 45-60KT MIX DOWN IN SOME OF THE STRONGER CONVECTION.
THEN THE...SNOW...YUK! COLD AIR MOVING INTO THE AREA BEHIND THE
FRONT SHOULD CAUSE RAIN TO MIX WITH/CHANGEOVER TO WET SNOW ACROSS
THE WESTERN AND CENTRAL MOUNTAINS TUESDAY INTO TUESDAY NIGHT. AT
THIS TIME...I AM THINKING THAT THE PRECIP WILL BE WINDING DOWN
RATHER QUICKLY TUESDAY AFTERNOON INTO THE EVENING...MEANING THE
CHANGE- OVER WILL BE OCCURRING DURING THE DAY FOR THE MOST PART
WHICH IS USUALLY VITAL AT THIS TIME OF THE YEAR. STILL CAN`T RULE
OUT A COATING TO A COUPLE OF SLUSHY INCHES OF SNOW...WHICH COULD
RESULT IN HAZARDOUS TRAVEL AND ROAD CONDITIONS. THE BEST CHANCE
FOR A FEW INCHES OF WET SNOW WILL BE OVER THE HIGHEST ELEVATIONS
IN THE WESTERN ALLEGHENIES. NO HEADLINES ARE PLANNED AT THIS
POINT...BUT THE POTENTIAL HAS BEEN ADDRESSED IN OUR HWO.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
GROWING SEASON TECHNICALLY STARTS TUESDAY OVER MY SERN ZONES.
AFTER SOME COORDINATION WITH SURROUNDING OFFICES...HAVE AGREED TO
LEAN AWAY FROM ANY FROST/FREEZE HEADLINES...BUT THE LOWS WILL
LIKELY SUPPORT A FREEZE WATCH/WARNING BEING ISSUED AT SOME POINT
TODAY.
THE LAST OF THE SHOWERS WILL BE LEAVING THE REGION TUESDAY
EVENING LEADING THE WAY TO A FEW FAIR BUT ABNORMALLY CHILLY DAYS
FROM WEDNESDAY INTO THE END OF THE WEEK. RISING HEIGHTS/SW FLOW
ALOFT OVER THE EASTERN US IN RESPONSE TO FCST TROUGHING OVER THE
N-CENTRAL PLAINS SHOULD ALLOW FOR TEMPERATURES TO REBOUND TOWARD
THE WEEKEND.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS CONTINUE AT ALL LOCATION TONIGHT. WHILE THESE
CONDITIONS WILL PRETTY MUCH PREVAIL MOST OF THE OVERNIGHT AND
MONDAY...SOME MVFR CONDITIONS ARE EXPECTED LATE TONIGHT OVER THE
LOWER SUSQUEHANNA AIRFIELDS OF KMDT AND KLNS. THERE MAY BE SOME
OTHER PATCHY AREAS OF FOG AROUND OVERNIGHT AS WELL IN OTHER
LOCATIONS...BUT AT THIS POINT SEEMS PATCHY ENOUGH NOT TO INCLUDE
IN OTHER TAFS.
ADDITIONALLY...LLWS CONDITIONS CONTINUE OVER CENTRAL AND EASTERN
TAFS TONIGHT AS SURFACE WINDS DECOUPLE...GENERALLY REDUCING TO
UNDER 10 KNOTS. SHORT RANGE MODELS CONTINUE TO SHOW A HEALTHY LOW
LEVEL JET OF 35 TO 45 KNOTS FROM THE WSW OVERNIGHT. IN WESTERN
AREAS...UPPER FLOW IS LIGHTER...MAINLY 20 KNOTS OR SO. THEREFORE
DID NOT INCLUDE LLWS IN KJST AND KBFD.
WHILE SHOWERS AND THUNDERSTORMS SHOULD BE APPROACHING FROM THE
WEST TOMORROW...HAVE SLOWED THE ONSET OF LOWER CIGS AND VSBYS
UNTIL AFTER 00Z. DID INTRODUCE VCSH TO WESTERN AIRFIELDS...AND
WILL HAVE TO WATCH THE PROGRESSION OF PRECIPITATION TOMORROW.
THERE IS A RISK THAT SOME RESTRICTIONS MAY WORK INTO KBFD SHORTLY
BEFORE 00Z.
CONDITIONS ACROSS THE REGION WILL DETERIORATE LATER MONDAY INTO
TUESDAY WITH IFR CIGS AND REDUCED VSBY WITH PRECIPITATION MOVING
IN. CONVECTIVE CELLS ARE POSSIBLE WITH THE COLD FRONT.
OUTLOOK...
.MON...MAINLY VFR...WITH LOWERING CLOUDS. RESTRICTIONS POSSIBLE
IN THE WEST CLOSE TO 00Z.
.MON NIGHT-TUE...RAIN/REDUCED CIGS POSSIBLE...POSSIBLY ENDING AS
A BRIEF PERIOD OF WET SNOW ACROSS THE NORTHERN AND WESTERN MTNS.
.WED-THU...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...JUNG/MARTIN
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1213 AM CDT MON APR 14 2014
.UPDATE...FOR 06Z AVIATION FORECASTS
&&
.AVIATION...
SHOWERS AND TSTMS HAVE BEEN RACING NORTHEASTWARD TOWARD MIDDLE TN
THIS EVENING. A FEW LIGHT SHOWERS CROSSED FROM WEST TN INTO MIDDLE
TN AFTER 05Z WITH MORE POISED TO FOLLOW. SHOWERS AND ISOLATED
TSTMS WERE ALREADY BEGINNING TO IMPACT KCKV AREA AT 05Z...AND WILL
START IMPACTING KBNA AREA BY 06Z. PRECIP WILL SPREAD QUICKLY FROM
WEST TO EAST...AND SHOULD APPROACH KCSV BY 10Z.
GUSTY SOUTH WINDS WILL CONTINUE THE REST OF THE NIGHT WELL AHEAD
OF THE ADVANCING COLD FRONT WHICH STRETCHED FROM SE OK TO EASTERN
MO AT 05Z. FRONT IS PROGGED TO MOVE QUICKER THAN FORECAST
EARLIER...AND MAY ARRIVE AT KCKV BEFORE 21Z...KBNA AFTER
21Z...AND KCSV AROUND THE END OF THIS FORECAST CYCLE. BEST CHANCES
FOR SHOWERS/TSTMS WILL BE WITH THIS OVERNIGHT/EARLY MORNING
ACTIVITY BUT CHANCES WILL CONTINUE UNTIL A FEW HOURS AFTER THE FRONT
PASSES.
&&
.PREV DISCUSSION... /ISSUED 1112 PM CDT SUN APR 13 2014/
UPDATE...
THE APPROACHING SQUALL LINE IS TAKING ON A MORE ORGANIZED LINEAR
STRUCTURE WITH EMBEDDED BOWING SEGMENTS WITHIN THE SOUTHERN
PORTION OF THE LINE. WITH PLENTY OF MID LEVEL DRY AIR IN
PLACE...THE STRONG TO SEVERE WIND THREAT WILL CONTINUE. ALTHOUGH
DEVELOPMENT IS LESS ORGANIZED SOUTH OF THE I40 CORRIDOR.
THEREFORE...THINK THIS WIND THREAT WILL STAY MOSTLY NORTH OF THE
I40 CORRIDOR AND WEST OF THE I65 CORRIDOR MAINLY IMPACTING OUR NW
COUNTIES.
STORM TOPS ARE NOT EXCEEDING 25KFT SO HAIL DOES NOT APPEAR TO BE A
THREAT...HOWEVER THIS LINE HAS PRODUCED EMBEDDED ROTATIONS WITH
ALL THE OF THE AVAILABLE SHEARING PRESENT. STILL OVER 50 KT OF 0-6
KM BULK SHEAR IN WESTERN TENNESSEE AND WHILE THOSE SHEAR VALUES
DECREASE ENTERING MIDDLE TN...STILL WILL NEED TO KEEP AN EYE ON
EMBEDDED ROTATIONS THAT MAY RESULT DUE TO BOWING IN THE LINE. LCLS
ARE STILL VERY HIGH ACCORDING TO LATEST RUC SOUNDINGS SO THAT
DOES NOT BODE WELL FOR TORNADIC CHANCES.
PREV DISCUSSION... /ISSUED 805 PM CDT SUN APR 13 2014/
UPDATE...
500 MB JET STREAK IS BEGINNING TO ENTER THE MS RIVER VALLEY WHICH
IS LARGELY FUELING THE AREA OF SHOWERS AND THUNDERSTORMS IN THAT
REGION. THIS WILL CONTINUE TO PROGRESS EASTWARD OVER THE NEXT FEW
HOURS. MID LEVEL DRY AIR...AS SHOWN IN THE RUC TIME HEIGHT AND THE
00Z ROAB...SHOULD KEEP THE SHOWERS FROM ENTERING THE MID STATE BEFORE
06Z. THEREFORE...OPTED TO REMOVE POP CHANCES PRIOR TO 03Z AND ONLY
LEFT WESTERN AREAS IN SLGT CHC CATEGORY UNTIL 06Z. ALL SHORT RANGE
MODELS KEEP ANY QPF WEST OF THE TN RIVER UNTIL THAT POINT. POP
CHANCES RISE AFTER 06Z.
AS FOR TONIGHTS STORM SEVERITY POTENTIAL...CONVECTIVELY...THE
PARAMETERS ARE NOT IMPRESSIVE WITH CIN OVERCOMING CAPE ON THE RUC
FORECAST SOUNDINGS SHORTLY AFTER MIDNIGHT. HOWEVER...DYNAMICALLY
SPEAKING...A STOUT 850 MB LLJ AND 500 MB JET MAX SHOULD KEEP
THUNDER PLENTIFUL. GUSTY WIND POTENTIAL WILL BE STILL BE MODERATE
WITH THE INITIAL STORMS BETWEEN 03Z AND 09Z IN THE WEST DUE TO MID
LEVEL DRY AIR AND INVERTED V SOUNDINGS OUT WEST. PLUS...SHEAR
VALUES WOULD HINT AT THE POSSIBILITY OF SOME BOWING SEGMENTS WITH
THE MORE INTENSE STORMS WITHIN THE LINE. HOWEVER WIND POTENTIAL
SHOULD DROP OFF SUBSTANTIALLY SOON AFTER STORM ONSET AS THE LOW LEVEL
ATMOSPHERE MOISTENS WITH THE HEALTHY QPF WE SHOULD RECEIVE.
PREV DISCUSSION... /ISSUED 656 PM CDT SUN APR 13 2014/
UPDATE...FOR 00Z AVIATION FORECAST
AVIATION...
EXTENSIVE HIGH CLOUDS AND GUSTY WINDS WILL CONTINUE ACROSS MID TN
THIS EVENING AS UPPER DISTURBANCE MOVES TOWARD MS VALLEY. CIGS
WILL BEGIN TO LOWER AND RAIN CHANCES WILL GO UP AS MOISTURE
CONTINUES TO INCEASE LATER TONIGHT INTO MONDAY. BEST CHANCES FOR
SHOWERS AND ISOLATED TSTMS SHOULD BE IN A 2 TO 4 HOUR WINDOW THAT
STARTS AT 08Z AT KCKV...AT 09Z AT KBNA AND AFTER 12Z AT KCSV.
CONTINUED CHANCES FOR SHOWERS AND ISOLATED TSTMS MONDAY AFTERNOON
AS COLD FRONT MOVES SLOWLY INTO THE REGION. FRONT COULD MAKE IT
TO KCKV CLOSE TO 00Z TUE...BUT NOT UNTIL AFTER 00Z TUE AT
KBNA/KCSV.
PREV DISCUSSION... /ISSUED 222 PM CDT SUN APR 13 2014/
DISCUSSION...
CLOUDS WILL INCREASE THROUGH THE AFTERNOON AS SURFACE RIDGE BEGINS
TO WEAKEN OVER THE SOUTHEAST AS CENTRAL AND SOUTHERN PLAINS LOW
CONTINUES TO DEEPEN. GRADIENT BETWEEN THE TWO SYSTEMS IS TIGHT
ENOUGH TO KEEP WINDS UP TONIGHT AND DURING THE DAY ON MONDAY.
SHOWERS AND A FEW THUNDERSTORMS WILL WORK INTO FAR WESTERN MIDDLE
TENNESSEE AROUND MIDNIGHT AND TRANSLATE EASTWARD OVERNIGHT. MODELS IN
AGREEMENT IN COLD FRONT ALONG THE MISSISSIPPI RIVER BY 12Z MONDAY
WITH SHOWERS AND STORMS ACROSS THE MID STATE. A FEW STORMS COULD
BE STRONG TO MARGINIALLY SEVERE DURING THE DAY MONDAY. SURFACE WINDS
WILL BE GUSTY. FROPA AT CLARKSVILLE MONDAY AROUND 18Z...AND
AROUND 23Z AT NASHVILLE AND TOWARDS MIDNIGHT MONDAY NIGHT ALONG
THE PLATEAU. WINDS PICK UP IN SPEED OUT OF THE NORTHWEST AND GUSTY
MONDAY NIGHT...COULD SEE GUSTS TO 30 TO 35 MPH. SHARPLY COLDER
MONDAY NIGHT WITH LOWS DOWN IN THE MID AND UPPER 30S BUT NO FROST
DUE TO WIND AND CLOUDS. BLUSTERY DAY ON TUESDAY WITH HIGHS MOSTLY
IN THE UPPER 40S. (THE LOWEST DAILY HIGH AT NASHVILLE FOR APRIL
15TH (TUESDAY) IS 46 DEGREES SET BACK IN 1903). FREEZE LIKELY
TUESDAY NIGHT WITH LOWS RANGING FROM 28-32 DEGREES. HIGHS
WEDNESDAY THROUGH FRIDAY IN THE 60S WITH DRY WEATHER UNTIL FRIDAY
WHEN ANOTHER FRONTAL SYSTEM APPROACHES FROM THE WEST BRINGING A
CHANCE FOR SHOWERS AND A FEW THUNDERSTORMS. PLEASANT WEATHER OVER
THE WEEKEND WITH HIGHS AROUND 70.
CLIMATE...FREEZE LOOKS LIKELY TUESDAY NIGHT/WEDNESDAY MORNING
WITH LOWS RANGING FROM 28 TO 32 DEGREES. SENSITIVE PLANTS WILL
NEED TO BE PROTECTED. THE RECORD LOW AT NASHVILLE FOR APRIL 16TH
IS 28 DEGREES SET BACK IN 1988.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
49
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1112 PM CDT SUN APR 13 2014
.UPDATE...
THE APPROACHING SQUALL LINE IS TAKING ON A MORE ORGANIZED LINEAR
STRUCTURE WITH EMBEDDED BOWING SEGMENTS WITHIN THE SOUTHERN
PORTION OF THE LINE. WITH PLENTY OF MID LEVEL DRY AIR IN
PLACE...THE STRONG TO SEVERE WIND THREAT WILL CONTINUE. ALTHOUGH
DEVELOPMENT IS LESS ORGANIZED SOUTH OF THE I40 CORRIDOR.
THEREFORE...THINK THIS WIND THREAT WILL STAY MOSTLY NORTH OF THE
I40 CORRIDOR AND WEST OF THE I65 CORRIDOR MAINLY IMPACTING OUR NW
COUNTIES.
STORM TOPS ARE NOT EXCEEDING 25KFT SO HAIL DOES NOT APPEAR TO BE A
THREAT...HOWEVER THIS LINE HAS PRODUCED EMBEDDED ROTATIONS WITH
ALL THE OF THE AVAILABLE SHEARING PRESENT. STILL OVER 50 KT OF 0-6
KM BULK SHEAR IN WESTERN TENNESSEE AND WHILE THOSE SHEAR VALUES
DECREASE ENTERING MIDDLE TN...STILL WILL NEED TO KEEP AN EYE ON
EMBEDDED ROTATIONS THAT MAY RESULT DUE TO BOWING IN THE LINE. LCLS
ARE STILL VERY HIGH ACCORDING TO LATEST RUC SOUNDINGS SO THAT
DOES NOT BODE WELL FOR TORNADIC CHANCES.
&&
.PREV DISCUSSION... /ISSUED 805 PM CDT SUN APR 13 2014/
UPDATE...
500 MB JET STREAK IS BEGINNING TO ENTER THE MS RIVER VALLEY WHICH
IS LARGELY FUELING THE AREA OF SHOWERS AND THUNDERSTORMS IN THAT
REGION. THIS WILL CONTINUE TO PROGRESS EASTWARD OVER THE NEXT FEW
HOURS. MID LEVEL DRY AIR...AS SHOWN IN THE RUC TIME HEIGHT AND THE
00Z ROAB...SHOULD KEEP THE SHOWERS FROM ENTERING THE MID STATE BEFORE
06Z. THEREFORE...OPTED TO REMOVE POP CHANCES PRIOR TO 03Z AND ONLY
LEFT WESTERN AREAS IN SLGT CHC CATEGORY UNTIL 06Z. ALL SHORT RANGE
MODELS KEEP ANY QPF WEST OF THE TN RIVER UNTIL THAT POINT. POP
CHANCES RISE AFTER 06Z.
AS FOR TONIGHTS STORM SEVERITY POTENTIAL...CONVECTIVELY...THE
PARAMETERS ARE NOT IMPRESSIVE WITH CIN OVERCOMING CAPE ON THE RUC
FORECAST SOUNDINGS SHORTLY AFTER MIDNIGHT. HOWEVER...DYNAMICALLY
SPEAKING...A STOUT 850 MB LLJ AND 500 MB JET MAX SHOULD KEEP
THUNDER PLENTIFUL. GUSTY WIND POTENTIAL WILL BE STILL BE MODERATE
WITH THE INITIAL STORMS BETWEEN 03Z AND 09Z IN THE WEST DUE TO MID
LEVEL DRY AIR AND INVERTED V SOUNDINGS OUT WEST. PLUS...SHEAR
VALUES WOULD HINT AT THE POSSIBILITY OF SOME BOWING SEGMENTS WITH
THE MORE INTENSE STORMS WITHIN THE LINE. HOWEVER WIND POTENTIAL
SHOULD DROP OFF SUBSTANTIALLY SOON AFTER STORM ONSET AS THE LOW LEVEL
ATMOSPHERE MOISTENS WITH THE HEALTHY QPF WE SHOULD RECEIVE.
PREV DISCUSSION... /ISSUED 656 PM CDT SUN APR 13 2014/
UPDATE...FOR 00Z AVIATION FORECAST
AVIATION...
EXTENSIVE HIGH CLOUDS AND GUSTY WINDS WILL CONTINUE ACROSS MID TN
THIS EVENING AS UPPER DISTURBANCE MOVES TOWARD MS VALLEY. CIGS
WILL BEGIN TO LOWER AND RAIN CHANCES WILL GO UP AS MOISTURE
CONTINUES TO INCEASE LATER TONIGHT INTO MONDAY. BEST CHANCES FOR
SHOWERS AND ISOLATED TSTMS SHOULD BE IN A 2 TO 4 HOUR WINDOW THAT
STARTS AT 08Z AT KCKV...AT 09Z AT KBNA AND AFTER 12Z AT KCSV.
CONTINUED CHANCES FOR SHOWERS AND ISOLATED TSTMS MONDAY AFTERNOON
AS COLD FRONT MOVES SLOWLY INTO THE REGION. FRONT COULD MAKE IT
TO KCKV CLOSE TO 00Z TUE...BUT NOT UNTIL AFTER 00Z TUE AT
KBNA/KCSV.
PREV DISCUSSION... /ISSUED 222 PM CDT SUN APR 13 2014/
DISCUSSION...
CLOUDS WILL INCREASE THROUGH THE AFTERNOON AS SURFACE RIDGE BEGINS
TO WEAKEN OVER THE SOUTHEAST AS CENTRAL AND SOUTHERN PLAINS LOW
CONTINUES TO DEEPEN. GRADIENT BETWEEN THE TWO SYSTEMS IS TIGHT
ENOUGH TO KEEP WINDS UP TONIGHT AND DURING THE DAY ON MONDAY.
SHOWERS AND A FEW THUNDERSTORMS WILL WORK INTO FAR WESTERN MIDDLE
TENNESSEE AROUND MIDNIGHT AND TRANSLATE EASTWARD OVERNIGHT. MODELS IN
AGREEMENT IN COLD FRONT ALONG THE MISSISSIPPI RIVER BY 12Z MONDAY
WITH SHOWERS AND STORMS ACROSS THE MID STATE. A FEW STORMS COULD
BE STRONG TO MARGINIALLY SEVERE DURING THE DAY MONDAY. SURFACE WINDS
WILL BE GUSTY. FROPA AT CLARKSVILLE MONDAY AROUND 18Z...AND
AROUND 23Z AT NASHVILLE AND TOWARDS MIDNIGHT MONDAY NIGHT ALONG
THE PLATEAU. WINDS PICK UP IN SPEED OUT OF THE NORTHWEST AND GUSTY
MONDAY NIGHT...COULD SEE GUSTS TO 30 TO 35 MPH. SHARPLY COLDER
MONDAY NIGHT WITH LOWS DOWN IN THE MID AND UPPER 30S BUT NO FROST
DUE TO WIND AND CLOUDS. BLUSTERY DAY ON TUESDAY WITH HIGHS MOSTLY
IN THE UPPER 40S. (THE LOWEST DAILY HIGH AT NASHVILLE FOR APRIL
15TH (TUESDAY) IS 46 DEGREES SET BACK IN 1903). FREEZE LIKELY
TUESDAY NIGHT WITH LOWS RANGING FROM 28-32 DEGREES. HIGHS
WEDNESDAY THROUGH FRIDAY IN THE 60S WITH DRY WEATHER UNTIL FRIDAY
WHEN ANOTHER FRONTAL SYSTEM APPROACHES FROM THE WEST BRINGING A
CHANCE FOR SHOWERS AND A FEW THUNDERSTORMS. PLEASANT WEATHER OVER
THE WEEKEND WITH HIGHS AROUND 70.
CLIMATE...FREEZE LOOKS LIKELY TUESDAY NIGHT/WEDNESDAY MORNING
WITH LOWS RANGING FROM 28 TO 32 DEGREES. SENSITIVE PLANTS WILL
NEED TO BE PROTECTED. THE RECORD LOW AT NASHVILLE FOR APRIL 16TH
IS 28 DEGREES SET BACK IN 1988.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
TB12
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
417 AM CDT MON APR 14 2014
.DISCUSSION...
08Z SURFACE ANALYSIS INDICATED A STRONG COLD FRONT MOVING
SOUTHEAST ACROSS THE CWA...LOCATED NEAR A LINE FROM ATHENS TO
WACO TO LAMPASAS. JUST TO THE NORTHWEST OF THIS FRONT...A LINE OF
SCATTERED SHOWERS AND THUNDERSTORMS WAS OBSERVED...LIKELY
ASSOCIATED WITH THE 850 MB REFLECTION OF THE COLD FRONT. AT
0830Z...NONE OF THIS ACTIVITY WAS STRONG IN NATURE...AND AS
ALLUDED TO ABOVE...IT IS ALL ELEVATED IN NATURE OVER THE FRONTAL
INVERSION. REGIONAL SURFACE OBSERVATIONS INDICATE UNSEASONABLY
COLD AIR BEHIND THE FRONT...WITH TEMPERATURES IN THE LOWER 40S
LOCATED OVER WICHITA FALLS. NORTH WINDS WERE ALREADY RELATIVELY
STRONG BEHIND THE FRONT...WITH MANY LOCATIONS OBSERVING WINDS IN
THE 20 TO 25 MPH RANGE EARLY THIS MORNING.
THIS MORNING...WENT AHEAD AND CANCELLED THE SEVERE THUNDERSTORM
WATCH IN COORDINATION WITH THE SPC AND WFO SHV AS THE COLD FRONT
HAD UNDERCUT ALL ONGOING CONVECTION. THIS DOES NOT MEAN IT/S
IMPOSSIBLE TO GET STRONG STORMS THIS MORNING...HOWEVER THE ONLY
STRONG TO MARGINALLY SEVERE STORM HAZARD ASSOCIATED WITH ELEVATED
STORMS IS GOING TO BE IN THE FORM OF HAIL. RAP FORECAST SOUNDINGS
INDICATE THE PRESENCE OF 1000-1500 J/KG OF MUCAPE AVAILABLE FOR
THESE ELEVATED STORMS. DEEP LAYER SHEAR VALUES LOOK
IMPRESSIVE...BUT ARE NOT REALLY RELEVANT FOR THIS ACTIVITY AS THE
BULK OF THE CONTRIBUTION TO THE HIGHER SHEAR VALUES OCCURS BELOW
THE FRONTAL INVERSION. DEEP LAYER BULK SHEAR CALCULATIONS INDICATE
ABOUT 60 KTS OF SHEAR...WHILE EFFECTIVE BULK SHEAR IS MORE
REALISTICALLY AROUND 25 KTS. AS A RESULT...STRONG...BUT LIKELY
UNORGANIZED ELEVATED CONVECTION IS POSSIBLE THIS MORNING. BASED ON
THE RADAR PRESENTATION OF STORMS SO FAR EARLY THIS
MORNING...CHANCES ARE NO LARGE HAIL WILL FALL ACROSS THE
CWA...HOWEVER IF IT DOES OCCUR...HAIL WILL LIKELY BE CLOSE TO 1
INCH OR QUARTER SIZE IN DIAMETER.
REMAINDER OF TODAY...THE 850 MB FRONT WILL SLIDE SOUTHEAST OF THE
CWA BY LATE THIS MORNING...TAKING ALL THUNDERSTORM CHANCES
SOUTHEAST OUT OF THE AREA IN ITS WAKE. RELATIVELY STRONG ISENTROPIC
DOWNGLIDE/COLD AIR ADVECTION WILL DOMINATE THE LOWER TROPOSPHERE
IN THE WAKE OF THIS FRONT. A STRONG UPPER LEVEL LOW PRESSURE
SYSTEM WILL MOVE FROM WEST TO EAST OVER THE SOUTH PLAINS
TODAY...WHICH WILL SPREAD SOME STRONG LARGE SCALE FORCING FOR
ASCENT OVER THE CWA THIS AFTERNOON. HOWEVER...THE LARGE SCALE
FORCING FOR ASCENT ASSOCIATED WITH THIS UPPER LOW IS NOT EXPECTED
TO PENETRATE MUCH DEEPER THAN THE MIDDLE TROPOSPHERE TODAY BECAUSE
THE MIDDLE TO LOW TROPOSPHERE WILL BE DEFINED BY HIGH STATIC
STABILITY. A THERMODYNAMICALLY STABLE LAYER RESISTS VERTICAL
MOTIONS...AND THEREFORE SHOULD PREVENT ANY ADDITIONAL
PRECIPITATION FROM DEVELOPING OVER THE CWA TODAY ASSOCIATED WITH
THIS UPPER LOW. THIS IS SUCH A STRONG UPPER TROUGH THAT IT WOULD
BE A HUGE SURPRISE TO SEE SOME WEAK RADAR RETURNS DEVELOP OVER THE
CWA EARLY THIS AFTERNOON...BUT THE COLD FRONT PUSHING THROUGH THE
AREA JUST LOOKS TOO STRONG AND COLD TO ALLOW FOR MUCH LIFT TO
OCCUR WHERE WE WOULD NEED IT TO GET RAIN SHOWERS...THAT BEING THE
MID TO LOWER TROPOSPHERE.
ASIDE FROM PRECIPITATION CONCERNS...BEHIND THE FRONT WE SHOULD
JUST SEE STRONG NORTH WINDS AND COLD AIR ADVECTION THROUGHOUT THE
DAY TODAY. TEMPERATURES ARE EXPECTED TO INCREASE INTO THE LOWER TO
MID 50S BY LATE THIS AFTERNOON DESPITE THE STRONG COLD AIR
ADVECTION AS SKIES CLEAR OUT RAPIDLY BEHIND THE PASSAGE OF THE
UPPER TROUGH. EVEN THOUGH THE AIR BEHIND THE FRONT WILL REMAIN
COLD...THE SUN ANGLE IS GETTING TOO HIGH FOR US NOT TO HEAT UP A
BIT EVEN WITH JUST A FEW HOURS OF SUNSHINE. A WIND ADVISORY
REMAINS IN EFFECT FOR THE ENTIRE AREA TODAY DUE TO NORTH WINDS OF
25 TO 30 MPH BEHIND THE FRONT. WINDS SHOULD DIMINISH AN HOUR OR
TWO AFTER SUNSET AS HIGH PRESSURE BEGINS TO MOVE INTO THE REGION.
TONIGHT...HIGH PRESSURE IS EXPECTED TO SLIDE SOUTH-SOUTHEAST
ACROSS TEXAS FROM THE TX PANHANDLE TONIGHT. THIS WILL RESULT IN
NEARLY CALM WINDS ACROSS WEST CENTRAL TEXAS...AND LIGHT NORTHERLY
WINDS TO THE EAST. LIGHT WINDS AND CLEAR SKIES WILL MAKE FOR AN
IDEAL RADIATIONAL COOLING ENVIRONMENT RESULTING IN TEMPERATURES
FALLING INTO THE UPPER 20S TO MID 30S ACROSS THE CWA. YES...YOU
READ THAT CORRECTLY...PARTS OF NORTH AND CENTRAL TEXAS ARE
EXPECTED TO FALL BELOW FREEZING TONIGHT INTO TUESDAY MORNING. THIS
IS PUSHING RECORD TERRITORY FOR A LATE FREEZE WHICH IS QUITE
REMARKABLE CONSIDERING RECORDS HAVE BEEN KEPT SINCE THE LATE 1800S
TO EARLY 1900S...SO WE ARE LOOKING AT AN EVENT THAT HAS A RETURN
INTERVAL OF OVER 100 YEARS...FOR NORTH AND CENTRAL TEXAS AT LEAST.
AS A RESULT...THIS FREEZE...ASSUMING IT OCCURS AS FORECAST...HAS
THE POTENTIAL TO DO QUITE A BIT OF DAMAGE TO OUTDOOR PLANTS AS
MOST FOLKS WOULD NOT HAVE WAITED THIS LONG TO GET THEIR SPRING
PLANTING TAKEN CARE OF. AT ANY RATE...THIS IS WHY FREEZE WARNINGS
ARE ISSUED...TO GIVE FOLKS A CHANCE TO PROTECT THEIR PLANTS.
A FREEZE WARNING IS IN EFFECT FROM 1 AM TO 10 AM TONIGHT/TUESDAY
MORNING FOR LOCATIONS ALONG AND NORTHWEST OF A LINE FROM SULPHUR
SPRINGS TO KELLER TO WACO TO LAMPASAS. LOCATIONS JUST SOUTHEAST OF
THIS LINE GENERALLY HAVE FORECAST LOWS AT 33 DEGREES...SO THIS
WARNING MAY BE EXPANDED BASED ON HOW WARM WE GET THIS AFTERNOON
AND BASED ON NEW MODEL GUIDANCE THROUGHOUT THE DAY.
FORTUNATELY...MOST LOCATIONS IN THE FREEZE WARNING SHOULD SEE LOWS
FALL JUST BELOW FREEZING...GENERALLY 30 TO 32 DEGREES.
TEMPERATURES FALLING INTO THE UPPER 20S IS MORE LIKELY NORTH OF
INTERSTATE 30...NEAR THE RED RIVER.
TEMPERATURES ARE MORE LIKELY TO FALL BELOW FREEZING IN RURAL AREAS
MORE SO THAN URBAN AREAS. THE URBAN HEAT ISLAND EFFECT WILL KEEP
MOST OF THE CONCRETED AREAS OF THE METROPLEX ABOVE FREEZING.
TARRANT COUNTY IS INCLUDED IN THE FREEZE WARNING ANYWAYS BECAUSE
THE FAR NORTH AND WESTERN PORTIONS OF THE COUNTY...OUTSIDE OF THE
820 LOOP...ARE MORE LIKELY TO SEE FREEZING TEMPERATURES.
TEMPERATURES ARE EXPECTED TO CLIMB ABOVE FREEZING AREA WIDE AFTER
10 AM TUESDAY MORNING.
FROST IS POSSIBLE IN AREAS NOT INCLUDED IN THE FREEZE WARNING...SO
EVEN IF YOU ARE NOT IN THE FREEZE WARNING AT THIS TIME...IT MAY BE
PRUDENT TO PROTECT YOUR PLANTS ANYWAYS AS A PRECAUTION. THE AIR IS
EXPECTED TO BE VERY DRY...SO WIDESPREAD FROST IS NOT LIKELY...BUT
IT MAY BE BETTER TO BE SAFE THAN SORRY.
REMAINDER OF THE FORECAST...WE WILL WARM UP AFTER TUESDAY...WITH
NO MORE POTENTIAL FROSTS OR FREEZES IN THE FORECAST THROUGH NEXT
WEEKEND. TUESDAY NIGHTS LOWS WILL BE WELL BELOW NORMAL AGAIN...BUT
SHOULD FALL INTO THE MID TO UPPER 30S AT WORST. BY
WEDNESDAY...SOUTH WINDS WILL HELP BRING DEW POINTS BACK UP INTO
THE MID TO UPPER 40S...BRINGING ABOUT A RETURN TO MORE SEASONAL
TEMPERATURES DURING THE DAYTIME AND OVERNIGHT.
OUR NEXT CHANCE OF RAIN STILL LOOKS TO BE THURSDAY...ASSOCIATED
WITH AN UPPER LEVEL TROUGH PROGGED TO MOVE OVER THE SOUTHERN
PLAINS THURSDAY AFTERNOON. HOWEVER...THE ECMWF AND GFS BOTH KEEP
THE BULK OF THE UPPER LEVEL FORCING FOR ASCENT ASSOCIATED WITH
THIS TROUGH NORTH OF THE CWA. ASSUMING THIS VERIFIES...THIS DOES
NOT USUALLY BODE WELL FOR PRECIPITATION CHANCES...EVEN WITH A WEAK
COLD FRONT PUSHING SOUTHEAST ACROSS THE CWA THURSDAY
AFTERNOON/EVENING. THE LOSS OF UPPER LEVEL DYNAMICS USUALLY MAKES
PRECIPITATION ALONG COLD FRONTS ISOLATED AT BEST. THE CANADIAN IS
FURTHER SOUTH WITH THIS UPPER TROUGH...AND THEREFORE HAS MUCH MORE
PRECIPITATION FOR THE CWA. WILL CONTINUE TO MONITOR THE EVOLUTION
OF THIS TROUGH IN FUTURE FORECASTS...HOWEVER FOR NOW JUST KEPT
POPS IN THE 20 TO 30 PERCENT RANGE IN LINE WITH THE GFS/ECMWF
SOLUTION.
AFTER THURSDAY...OUR NEXT SHOT AT RAIN LOOKS TO BE SATURDAY NIGHT
INTO SUNDAY...AS ALL GUIDANCE INDICATES AN UPPER LEVEL TROUGH WILL
MOVE OVER THE SOUTHWESTERN CONUS AND TOWARDS NORTH TX AT THAT
TIME. THE GFS IS THE MOST AGGRESSIVE WITH TAPPING INTO SOME
TROPICAL PACIFIC MOISTURE IN THE UPPER TROPOSPHERE COURTESY OF THE
SUB-TROPICAL JET. AS A RESULT THE GFS GIVES THE CWA A
GOOD...WIDESPREAD ONE HALF TO ONE INCH OF RAINFALL FROM SATURDAY
NIGHT THROUGH SUNDAY. WILL NOT BITE OFF ON THIS SOLUTION QUITE
YET...BUT IT IS A GOOD SIGN THAT AT LEAST ALL MODELS HAVE SOME
VERSION OF THIS TROUGH OVER THE SOUTHWESTERN CONUS. IF THIS
CONSISTENT CONTINUES...POPS WILL BE INCREASED AREA WIDE FOR
SATURDAY NIGHT INTO SUNDAY. THIS DOES NOT LOOK TO BE A GOOD SEVERE
WEATHER SET UP FOR NOW...SO A GOOD WIDESPREAD RAINFALL WITH
EMBEDDED THUNDERSTORMS IS WHAT IS EXPECTED AT THIS TIME. WE WILL
SEE HOW THINGS CHANGE AS WE GET CLOSER TO NEXT WEEKEND OF COURSE.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 55 34 63 42 66 / 10 5 0 0 0
WACO, TX 56 33 63 36 67 / 20 0 0 0 0
PARIS, TX 51 30 59 36 64 / 20 5 0 0 0
DENTON, TX 53 29 62 38 66 / 10 5 0 0 0
MCKINNEY, TX 53 30 62 38 65 / 10 5 0 0 0
DALLAS, TX 56 35 63 42 66 / 10 5 0 0 0
TERRELL, TX 55 33 62 37 65 / 20 5 0 0 0
CORSICANA, TX 54 33 61 38 66 / 20 5 0 0 0
TEMPLE, TX 58 33 64 36 68 / 30 0 0 0 0
MINERAL WELLS, TX 55 32 63 37 69 / 10 0 0 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 1 AM TO 10 AM CDT TUESDAY FOR TXZ091>095-
100>107-115>118-129>133-141>145-156-157-159.
WIND ADVISORY FROM 9 AM THIS MORNING TO 9 PM CDT THIS EVENING
FOR TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175.
&&
$$
/
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
455 AM EDT MON APR 14 2014
.SYNOPSIS...
LOW PRESSURE WAS OVER ILLINOIS WITH A COLD FRONT TRAILING FROM
THE LOW INTO TEXAS. THIS FRONT WILL MOVE EAST TODAY AND TONIGHT
AND WILL CROSS THE MID ATLANTIC REGION ON TUESDAY. BEHIND THE
FRONT HIGH PRESSURE WILL BUILD IN FOR WEDNESDAY THROUGH FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 415 AM EDT MONDAY...
WATER VAPOR LOOP SHOWED A WELL DEFINED SHORT WAVE CROSSING THROUGH
THE TENNESSE VALLEY. THICK CLOUD COVER WAS ALREADY SPREADING INTO
THE COUNTY WARNING AREA FROM THE WEST. SHORT RANGE MODELS
INCLUDING THE LATEST RUC/WRF AND HRRR BRING THE PRECIPITATION
ASSOCIATED WITH THIS WAVE INTO THE WESTERN COUNTY WARNING AREA
BETWEEN 15Z/11AM AND 18Z/2PM.
WITH ALL THE CLOUD COVER DO NOT EXPECT MUCH INSTABILITY. BUFKIT
OFF THE NAM AND GFS SHOWED LOW CAPE VALUES TODAY. HELD PROBABILITY
OF THUNDER TO SLIGHT CHANCE. DO EXPECT ISOLATED TO SCATTERED
SHOWERS AHEAD OF THE TENNESSEE VALLEY SHORT WAVE...WITH THE BETTER
AREAL COVERAGE IN THE MOUNTAINS THROUGH NOON. HIGH TODAY WILL
STILL BE ABOVE NORMAL BUT ONLY A SMALL RISE FROM THE CURRENT MILD
TEMPERATURES.
MUCH BETTER SYNOPTIC SCALE LIFT AFTER 00Z/8PM THIS EVENING. AS THE
COLD FRONT APPROACHES LATE TONIGHT...SURFACE AND LOW LEVEL WINDS
BACK...ADDING THE SOUTHEAST UPSLOPE COMPONENT TO THE STRONG
FORCING. LARGEST PRECIPITATION AMOUNTS WILL BE AFTER MIDNIGHT.
FRONT DOES NOT REACH THE FAR WESTERN PART OF THE FORECAST AREA
BEFORE 12Z/8AM. STAYED CLOSER TO THE WARMER GUIDANCE FOR OVERNIGHT
LOWS. THE LOW LEVEL JET INCREASES OVERNIGHT. HIGHER ELEVATIONS
MAY HAVE GUSTS OF 25 TO 30 MPH.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
AS OF 400 AM EDT MONDAY...
A STRONG COLD FRONT WILL MAKE ITS WAY ACROSS THE FORECAST AREA
BEGINNING TUESDAY MORNING...AND THEREFORE WILL HAVE SEVERAL THINGS
TO KEEP AN EYE. MODELS CONTINUE TO INDICATE A SOUTHWESTERLY 55KT LOW
LEVEL JET DEVELOPING AHEAD OF THE FRONT. INSTABILITY AHEAD OF THE
FRONT WILL BE MARGINAL...RESULTING IN MAINLY HEAVY SHOWER ACTIVITY
WITH ONLY ISOLATED THUNDER AS THE FRONT PASSES. HOWEVER...WITH THE
JET BLOWING JUST OFF THE SURFACE OVER THE MOUNTAINS...WOULD NOT BE
SURPRISED TO SEE SOME OF THE MORE INTENSE SHOWER ACTIVITY DRAW THE
STRONGER WINDS DOWN TO THE GROUND LEVEL.
HIGH PRESSURE WILL BUILD IN QUICKLY AFTER THE COLD FRONT PASSES...
RESULTING IN A ROUGHLY 10MB PRESSURE GRADIENT ACROSS THE FORECAST
AREA FROM MID AFTERNOON THROUGH ALMOST MIDNIGHT. EXPECT STRONG
NORTHWEST WINDS WITH 40 TO 50 MPH GUSTS ACROSS THE MOUNTAINS...WITH
THE STRONGEST GUSTS FOUND ALONG THE BLUE RIDGE PARKWAY SOUTH OF
ROANOKE. THESE GUSTS...WHEN COMBINED WITH PROLONGED RAINFALL...WILL
LIKELY BE ENOUGH TO BRING DOWN A FEW TREES...AND RESULT IN LOCALIZED
POWER OUTAGES.
RAINFALL WILL BE WIDESPREAD AND HEAVY AT TIMES...WITH A STORM TOTAL
AMOUNT OF OVER AN INCH FOR THE ENTIRE FORECAST AREA...WITH AROUND 2
INCHES EXPECTED ALONG THE BLUE RIDGE. MAY SEE LOCALIZED MINOR
FLOODING ISSUES DEVELOP WHERE BANDS OF HEAVY RAIN PASS REPEATEDLY
OVER THE SAME LOCATIONS. RAINFALL MAY ALSO PUSH SOME RIVERS TO
BANKFULL OR MINOR FLOOD LATER IN THE WEEK.
FOR THE FIRST FEW HOURS AFTER FRONTAL PASSAGE...TEMPERATURES WILL
PLUMMET AT A RATE OF 6 TO 9 DEGREES PER HOUR. EXPECT TEMPERATURES TO
APPROACH FREEZING FROM SOUTHEAST WEST VIRGINIA THROUGH THE NORTH
CAROLINA MOUNTAINS BY EARLY EVENING...ALLOWING RAIN SHOWERS TO
CHANGE OVER TO SNOW. WHILE WARM GROUND TEMPERATURES WILL CAUSE SNOW
TO MELT ON CONTACT ACROSS MANY AREAS...MAY SEE UP TO A HALF INCH OF
SNOW ACCUMULATE ALONG OUR MORE PROMINENT WEST FACING SLOPES BEFORE
SNOW SHOWERS END OFF SHORTLY AFTER MIDNIGHT WEDNESDAY.
NEXT WE GET TO DEAL WITH SUB FREEZING TEMPERATURES AREAWIDE BY
SUNRISE WEDNESDAY. EXPECT OVERNIGHT LOWS TO RANGE FROM THE MID 20S
ACROSS SOUTHEAST WEST VIRGINIA TO THE LOW 30S ACROSS THE SOUTHSIDE.
PRECAUTIONS SHOULD BE TAKEN TO PROTECT ANY PLANTS THAT MAY BE KILLED
BY FREEZING TEMPERATURES.
HIGH PRESSURE WILL PASS FROM THE GREAT LAKES TO NEW ENGLAND ON
WEDNESDAY...AND WILL BUILD SOUTHWARD ALONG THE EASTERN FACE OF THE
APPALACHIANS. THE NORTHEASTERLY WIND FLOW AROUND THE HIGH WILL KEEP
COOL CONDITIONS IN PLACE HEADING INTO THE SECOND HALF OF THE
WORKWEEK...WITH FREEZING TEMPERATURES LIKELY AGAIN WEDNESDAY NIGHT.
A GRADUAL WARM UP WILL TAKE PLACE THURSDAY AS WINDS ALOFT BEGIN TO
SHIFT SOUTHWESTERLY AGAIN.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 200 PM EDT SATURDAY...
EXPECT HIGH PRESSURE TO REMAIN IN CONTROL OF THE WEATHER PATTERN FOR
FRIDAY. A COLD FRONT WILL APPROACH FROM THE WEST FRIDAY NIGHT INTO
SATURDAY. GENERALLY FOLLOWED WPCGUIDE FOR POPS. STILL LOOKS LIKE
THE BEST CHANCE FOR WIDESPREAD RAIN WILL OCCUR ON FRIDAY NIGHT
INTO SATURDAY. LEANED TOWARDS THE ECENS MEAN WITH HANDLING THE
SOUTHERN STREAM SYSTEM AND ITS MOISTURE. TEMPERATURES MODERATE
TOWARD NEXT WEEKEND CLOSER TO NORMAL.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
AS OF 130 AM EDT MONDAY...
CEILINGS WILL GRADUALLY LOWER THIS MORNING. MVFR CLOUDS WILL FORM
ALONG THE BLUE RIDGE AND IN THE FOOTHILLS BEFORE 12Z. THERE IS
A LOW POSSIBILITY THAT CEILINGS WILL EVEN DROP TO IFR AT KBCB
BEFORE 12Z.
MODELS BRING THE SHORT WAVE ENTERING THE TENNESSEE VALLEY ACROSS
THE REGION MAINLY BETWEEN 15Z/11AM AND 21Z/5PM. WITH ALL THE
CLOUD COVER DURING THE DAY...THERE WILL BE ONLY A LIMITED THREAT
OF ANY THUNDER. MODERATE CONFIDENCE THAT VISIBILITIES WILL REMAIN
VFR AND NOT LOWER AS THE SHOWERS MOVE THROUGH.
THE STRONG COLD FRONT WILL ARRIVE IN THE MOUNTAINS BY 12Z/8AM
TUESDAY. WILL HOLD OFF ADDING ANOTHER PERIOD OF RAINFALL IN UNTIL
AFTER THE END OF THE 06Z TAFS.
LOOKS WET TUESDAY THRU TUESDAY NIGHT. STRONG GUSTY NW WINDS ARE
LIKELY BEHIND THE FRONT TUESDAY AFTERNOON AND NIGHT. DRIER AIR
WORKS IN BEHIND THE SYSTEM FOR WEDNESDAY ALTHOUGH RESIDUAL
MOISTURE AND COLD AIR ALOFT MAY ACT TO KEEP MVFR CIGS OVER THE
MOUNTAINS ON TUESDAY NIGHT. VFR THEN EXPECTED THURSDAY WITH HIGH
PRESSURE RIDGING IN FROM OFF NEW ENGLAND BETWEEN THE EXITING FRONT
OFFSHORE AND THE NEXT COLD FRONT TO THE NW. NEXT COLD FRONT
APPROACHES FROM THE WEST FRIDAY BUT APPEARS SLOW ENOUGH TO
MAINTAIN VFR DURING THE DAY FOR NOW.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...NF
LONG TERM...KK
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
345 AM CDT MON APR 14 2014
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 345 AM CDT MON APR 14 2014
MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES TODAY AND
THEN TUESDAY NIGHT INTO WEDNESDAY.
SURFACE ANALYSIS SHOWS AN AREA OF LOW PRESSURE OVER NORTHERN
ILLINOIS. LOCAL AND REGIONAL RADARS SHOWING THE DEFORMATION BAND
OF PRECIPITATION ON THE NORTHWEST SIDE OF THE LOW EXTENDS FROM
SOUTHERN IOWA ACROSS THE AREA INTO EASTERN LAKE SUPERIOR. COLDER
AIR HAS FILTERED IN AND CHANGED MOST OF THE PRECIPITATION OVER TO
SOME LIGHT SNOW. THE PRECIPITATION IS MOVING TO THE NORTHEAST AND
THE 14.05Z HRRR SEEMS TO HAVE A GOOD HANDLE ON THE CURRENT
SITUATION. IT INDICATES THAT BY 12Z THE BACK EDGE OF THE
PRECIPITATION COMING OUT OF SOUTHERN IOWA WILL HAVE SHIFTED INTO
SOUTHERN WISCONSIN WITH THE WESTERN EDGE INTO THE WESTERN AND
CENTRAL PARTS OF WISCONSIN. WILL ADJUST THE MORNING SNOW CHANCES
BASED ON RADAR TRENDS...BUT EXPECT THAT THE MAJORITY OF THE
ACTIVITY SHOULD BE EAST OF THE FORECAST AREA BY 12Z AND THEN WHAT
IT IS LEFT WILL QUICKLY DISSIPATE BY THE MID MORNING HOURS.
HIGH PRESSURE WILL THEN BUILD IN OVER THE UPPER MIDWEST AND LINGER
INTO TUESDAY BEFORE DEPARTING TO THE NORTHEAST. THE HIGH WILL HELP
TO KEEP TEMPERATURES BELOW NORMAL WITH HIGHS TODAY ONLY IN THE
30S FOR THE ENTIRE AREA AND THEN IN THE 30S AND 40S FOR TUESDAY.
THE NEXT CHANCE FOR SOME PRECIPITATION WILL START TO COME IN
TUESDAY NIGHT AND CONTINUE INTO WEDNESDAY. THIS WILL BE IN
RESPONSE TO A SHORT WAVE TROUGH THAT WILL CROSS THE NORTHERN
ROCKIES TUESDAY NIGHT AND MOVE OUT OVER THE UPPER MIDWEST
WEDNESDAY. THE BEST PV ADVECTION IN THE 500-300 MB LAYER IS
EXPECTED TO REMAIN NORTHWEST OF THE AREA THROUGH WEDNESDAY...BUT
THE WAVE SHOULD STILL BE ABLE TO PRODUCE AT LEAST SOME WEAK PV
ADVECTION OVER THE NORTHWEST SECTIONS OF THE FORECAST AREA. LOW
PRESSURE AT THE SURFACE IS EXPECTED TO MOVE EAST ACROSS SOUTH
DAKOTA DURING THE DAY WEDNESDAY WITH A WARM FRONT EXTENDING EAST
INTO WISCONSIN. WEAK FRONTOGENESIS IN THE 1000-700 MB LAYER IS
EXPECTED TO DEVELOP ALONG AND NORTH OF THE WARM FRONT ACROSS
MINNESOTA AND WISCONSIN. THE WARM AIR ADVECTION AHEAD OF THE SHORT
WAVE TROUGH AND SURFACE LOW IS EXPECTED TO PRODUCE 5 TO 8 UBAR/S
OF UP GLIDE ON THE 290K ISENTROPIC SURFACE. WITH THE FORCING FROM
THE SHORT WAVE TROUGH AND THE LOW LEVEL FRONTOGENESIS AND
ISENTROPIC UP GLIDE...EXPECT TO SEE PRECIPITATION BEGIN TO DEVELOP
ALONG AND NORTH OF THE WARM FRONT LATE TUESDAY NIGHT AND CONTINUE
INTO WEDNESDAY. WILL START OUT WITH SOME SMALL CHANCES ALONG AND
NORTH OF INTERSTATE 94 LATE TUESDAY NIGHT AND THEN SPREAD THE
CHANCES SOUTH TO ABOUT THE IOWA/MINNESOTA BORDER WEDNESDAY WHILE
INCREASING TO 50 PERCENT ACROSS THE FAR NORTH. BUFKIT SOUNDINGS
INDICATE THAT ICE WILL BE PRESENT IN THE CLOUDS AND THERE SHOULD
NOT BE A WARM LAYER TO DEAL WITH...SO THE PRECIPITATION TYPE
SHOULD BE CONTROLLED BY THE BOUNDARY LAYER TEMPERATURES. WILL
START WITH ALL SNOW TUESDAY NIGHT GOING TO RAIN WEDNESDAY AS
READINGS WARM INTO THE 40S AND 50S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 AM CDT MON APR 14 2014
SLOW AND COMPLICATED UPPER AIR PATTERN WILL KEEP THE PRECIPITATION
CHANCES IN THE FORECAST THROUGH THE WEEKEND. ONCE THE FIRST SHORT
WAVE TROUGH MOVES PAST THE REGION WEDNESDAY NIGHT...ALL THE MODELS
SHOW A CUT OFF LOW FORMING OVER SOUTHERN SASKATCHEWAN FROM A
STRONG NORTHERN STREAM SHORT WAVE TROUGH COMING DOWN FROM THE
NORTHERN CANADA. THIS IS EXPECTED TO KEEP THE MEAN LONG WAVE
TROUGH ALONG AND EAST OF THE ROCKIES WITH SEVERAL SHORT WAVE
TROUGHS COMING THROUGH THIS LONG WAVE TROUGH. THE CLOSED LOW
SHOULD THEN OPEN UP AND START TO MOVE EAST WITH THE LONG WAVE
TROUGH PASSING OVER FOR THE WEEKEND. WITHIN THIS EXTENDED PERIOD
OF PRECIPITATION CHANCES...THE BEST CHANCES LOOK TO OCCUR THURSDAY
NIGHT INTO FRIDAY WHEN A STRONG SHORT WAVE TROUGH IS SHOWN BY THE
MODELS TO MOVE ACROSS THE REGION. TEMPERATURES STILL LOOK TO BE
COOL ENOUGH FOR SNOW OR A RAIN/SNOW MIX AT NIGHT GOING TO RAIN
DURING THE DAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1140 PM CDT SUN APR 13 2014
AS SHORT WAVE CONTINUES TO PUSH EAST TONIGHT...PRECIPITATION HAS
BEEN WAINING. COLUMN HAS BEEN COOLING AS WELL ALLOWING RAIN TO
CHANGE OVER TO SNOW FROM WEST TO EAST. BUT OVERALL CONDITIONS HAVE
BEEN IMPROVING WITH LESS LIFR AND MORE MVFR BEING OBSERVED AROUND
THE AREA.
OVER THE NEXT FEW HOURS...EXPECT RAIN AND SNOW TO END. BEFORE THEN
COULD SEE A DEFORMATION ZONE DEVELOP AND BRING ONE MORE ROUND OF
SNOW TO KRST BEFORE ENDING. MVFR CEILINGS EXPECTED TOWARDS DAYBREAK
AND THEN AS SYSTEM EXITS...COULD SEE VFR FOR MUCH OF THE DAY.
A BIT UNSURE ON WHAT CLOUDS WILL DO MONDAY AFTERNOON AS UPPER TROUGH
SETTLES IN. COULD SEE SOME LOW CLOUD DEVELOPMENT GIVEN MID APRIL SUN
BUT AM BANKING THAT MID LEVEL CLOUDS AROUND WILL BE ABOUT IT. STIFF
NORTHWEST WINDS SHOULD ALSO SUBSIDE AS WEATHER SYSTEM EXITS BY
MONDAY EVENING.
&&
.HYDROLOGY...
ISSUED AT 345 AM CDT MON APR 14 2014
PARTS OF SOUTHWEST WISCONSIN RECEIVED BETWEEN 2 AND 4 INCHES OF
RAIN OVER THE WEEKEND. THIS HAS RESULTED IN SATURATED SOILS AND
RUNOFF INTO AREAS STREAMS. THIS HAS RESULTED IN MAINLY IN BANK
RISES BUT THE LATEST FORECASTS INDICATE SOME MINOR FLOODING IS
POSSIBLE ALONG THE KICKAPOO IN THE VICINITY OF READSTOWN. SOME
FLOODING LATER THIS WEEK IS POSSIBLE ALONG THE MISSISSIPPI RIVER
AS RUNOFF FROM THE SNOWMELT UPSTREAM AND THE RECENT RAINS MOVES
DOWNSTREAM.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...SHEA
HYDROLOGY...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1140 PM CDT SUN APR 13 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 343 PM CDT SUN APR 13 2014
BUSY PERIOD TONIGHT INTO TOMORROW MORNING AS A LOW PRESSURE SYSTEM
TRACKS THROUGH NORTHERN ILLINOIS. HEAVY RAIN...SNOW...AND STRONG
WINDS ARE ALL CONCERNS TONIGHT INTO TOMORROW MORNING.
CURRENTLY...THE LEAD MID LEVEL TROUGH IS PROPAGATING TO THE NORTH
ACROSS THE MID-MISSISSIPPI RIVER VALLEY WITH SOME LOW LEVEL
CONVERGENCE OCCURRING ALONG A SOUTHWEST TO NORTHEAST ORIENTED WARM
FRONT THAT RUNS FROM SOUTHEAST IOWA THROUGH SOUTHERN WISCONSIN.
MODERATE TO HEAVY RAIN HAS ALREADY MOVED INTO NORTHEAST IOWA AND
SOUTHWEST WISCONSIN AND WILL CONTINUE TO TRACK TO THE NORTHEAST
INTO THIS EVENING AS THE SURFACE LOW MOVES UP IN THE REGION. MOST
OF THE 0-3KM MUCAPE THAT THE 13.19Z RAP SHOWS STAYS IN NORTHERN
ILLINOIS AND DOES NOT REACH THE REGION. SO...THINKING THAT THERE
SHOULD NOT BE MUCH LIGHTNING WITH THIS RAIN INTO THE EVENING
HOURS. WITH 1 TO 2 INCHES OF RAIN STILL FORECAST FOR THE SAME
AREAS THAT WERE HIT BY 1 TO 3 INCHES OF RAIN YESTERDAY...HAVE KEPT
THE FLOOD WATCH GOING FOR NORTHEAST IOWA AND SOUTHWEST WISCONSIN.
TO THE WEST SIDE OF THE SYSTEM WE GO WHERE THE CONCERN IS ON WHEN
THE THERMAL PROFILE WILL COOL ENOUGH TO CHANGE THE PRECIPITATION
OVER TO ALL SNOW ALONG WITH HOW WINDY IT WILL BE. IN REGARD TO THE
SNOW...WITH LOW TO MID LEVEL COLD AIR ADVECTION KICKING IN THIS
EVENING AS THE LOW DEEPENS...THE PRECIPITATION TYPE WILL BE
DEPENDENT UPON WHAT THE SURFACE TEMPERATURES ARE. LOOKING OUT WEST
RIGHT NOW...MOST OBSERVATIONS THAT ARE REPORTING SNOW ARE IN THE
30F TO 35F RANGE THOUGH SOME OF THESE TEMPERATURE DROPS APPEAR TO
BE DUE TO EVAPORATIVE COOLING THANKS TO THE PRECIPITATION FALLING
THROUGH THE COLUMN. BASED ON THE 13.19Z RAP & 13.12Z NAM/GFS
SOUNDINGS...IT LOOKS LIKE THE CHANGE OVER SHOULD OCCUR TO ALL SNOW
THIS EVENING BETWEEN 8-10PM IN NORTH CENTRAL IOWA AND SOUTHEAST
MINNESOTA. THIS CHANGE OVER WILL THEN GRADUALLY PUSH EASTWARD INTO
WESTERN WISCONSIN OVERNIGHT. SNOW TOTALS ARE PROBLEMATIC AS A
RESULT SINCE A LOT HINGES ON HOW FAST THE CHANGE OVER OCCURS...IS
THERE STRONG FORCING STILL THERE AS THE COLD AIR ARRIVES...AND
ALSO IF THERE EVEN IS ICE THERE AS A LOT OF THE SOUNDINGS SHOW A
DRY LAYER BETWEEN -8C TO -20C. MOST OF THE 13.12Z COBB DATA FROM
THE NAM/GFS IS SHOWING ABOUT 1 TO 2 INCHES OCCURRING OVERNIGHT
THOUGH A LOT OF THE SREF DATA IS MUCH HIGHER THAN THAT. GIVEN THE
NUMBER OF NEGATIVES WORKING AGAINST THIS...TRENDED TOWARD THESE
LOWER TOTALS WHICH STILL ARE A BIT HIGHER THAN WHAT PREVIOUSLY WAS
BEING FORECAST BY GUIDANCE. THE MAIN SNOW SHOULD FALL BETWEEN
7PM-1AM IN NORTHEAST IOWA/SOUTHEAST MINNESOTA AND THEN BETWEEN
1AM-7AM IN WESTERN WISCONSIN/FAR NORTHEAST IOWA.
WINDS WILL CONTINUALLY INCREASE THROUGH TONIGHT AS THE PRESSURE
GRADIENT TIGHTENS UP WITH THE LOW. THE STRONGEST LOW LEVEL WINDS
HAVE ALREADY DEVELOPED ACROSS WESTERN IOWA WHERE 30 TO 40KT WINDS
ARE FAIRLY WIDESPREAD IN THE AREA WHERE SNOW IS FALLING. CONCERNED
THAT THESE CONDITIONS WILL TRANSLATE EASTWARD INTO NORTHEAST IOWA
AND SOUTHEAST MINNESOTA THIS EVENING. THE STRONGEST WINDS LOOK
LIKE THEY WILL MAINLY BE IN NORTHEAST IOWA WITH BUFKIT SOUNDINGS
SHOWING SOME 35 TO 40KT WINDS MIXING DOWN AS THE SNOW IS COMING
DOWN. DISCUSSED THE IDEA OF DOING A WINTER WEATHER OR WIND ADVISORY
WITH MPX/DMX...BUT DECIDED THAT THE WIND GUSTS MAY NOT HIT
ADVISORY CRITERIA AND SNOW AMOUNTS MAY NOT BE HIGH ENOUGH TO CAUSE
A LARGE IMPACT. CONDITIONS WILL HAVE TO BE MONITORED CLOSELY THIS
EVENING FOR A POSSIBLE QUICK UPGRADE WITH THE 9PM TO 3AM TIME
FRAME THE MAIN PERIOD OF CONCERN.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 343 PM CDT SUN APR 13 2014
THE MAIN STORIES THROUGH THIS WEEK ARE WITH THE POTENTIAL
ACCUMULATING SNOW ON TUESDAY NIGHT/WEDNESDAY AND ANOTHER SYSTEM
LATER IN THE WEEK.
MORE FOCUS WENT INTO THE TUESDAY NIGHT/WEDNESDAY SYSTEM SINCE
THERE IS QUITE A BIT OF UNCERTAINTY WITH THE LATE WEEK SYSTEM. THE
13.12Z NAM/GFS DEVELOPS A BAND OF SNOW ACROSS NORTHERN WISCONSIN
LATE TUESDAY NIGHT WHILE THE 13.12Z ECMWF KEEPS US DRY. SOME
ACCUMULATING SNOW IS LIKELY IN THE NAM/GFS SCENARIOS THOUGH ENOUGH
UNCERTAINTY IS THERE THANKS TO THE ECMWF. IT LOOKS LIKE WE GET
WARM SECTORED ON WEDNESDAY AS THE SYSTEM STALLS OUT WITH THE
PRECIPITATION SETTING UP FROM UPPER MICHIGAN DOWN THROUGH CENTRAL
IOWA ON THURSDAY. THE 13.12Z GFS THEN SPINS UP A POTENT SYSTEM FOR
FRIDAY THAT TRACKS THROUGH WISCONSIN WHILE EH ECMWF HARDLY HAS A
LOW DEVELOPING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1140 PM CDT SUN APR 13 2014
AS SHORT WAVE CONTINUES TO PUSH EAST TONIGHT...PRECIPITATION HAS
BEEN WAINING. COLUMN HAS BEEN COOLING AS WELL ALLOWING RAIN TO
CHANGE OVER TO SNOW FROM WEST TO EAST. BUT OVERALL CONDITIONS HAVE
BEEN IMPROVING WITH LESS LIFR AND MORE MVFR BEING OBSERVED AROUND
THE AREA.
OVER THE NEXT FEW HOURS...EXPECT RAIN AND SNOW TO END. BEFORE THEN
COULD SEE A DEFORMATION ZONE DEVELOP AND BRING ONE MORE ROUND OF
SNOW TO KRST BEFORE ENDING. MVFR CEILINGS EXPECTED TOWARDS DAYBREAK
AND THEN AS SYSTEM EXITS...COULD SEE VFR FOR MUCH OF THE DAY.
A BIT UNSURE ON WHAT CLOUDS WILL DO MONDAY AFTERNOON AS UPPER TROUGH
SETTLES IN. COULD SEE SOME LOW CLOUD DEVELOPMENT GIVEN MID APRIL SUN
BUT AM BANKING THAT MID LEVEL CLOUDS AROUND WILL BE ABOUT IT. STIFF
NORTHWEST WINDS SHOULD ALSO SUBSIDE AS WEATHER SYSTEM EXITS BY
MONDAY EVENING.
&&
.HYDROLOGY...
ISSUED AT 343 PM CDT SUN APR 13 2014
WITH MODERATE TO AT TIMES HEAVY RAIN FALLING INTO TONIGHT...WILL
KEEP THE FLOOD WATCH GOING FOR NORTHEAST IOWA AND SOUTHWEST
WISCONSIN. WITH 1 TO 3 INCHES OF RAIN FALLING LAST NIGHT ACROSS
THIS AREA AND ANOTHER 1 TO 2 INCHES POSSIBLE...SAW NO NEED TO DROP
IT. THERE DOES NOT APPEAR TO BE MUCH INSTABILITY THAT MAKES IT UP
IN THE REGION THIS AFTERNOON INTO TONIGHT...SO MOST OF THE RAIN
SHOULD NOT FALL AT A GREAT ENOUGH OF A RATE TO PROMPT FLASH
FLOODING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLOOD WATCH UNTIL 1 AM CDT MONDAY FOR WIZ043-044-053>055-061.
MN...NONE.
IA...FLOOD WATCH UNTIL 1 AM CDT MONDAY FOR IAZ030.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...SHEA
HYDROLOGY...HALBACH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1137 PM MDT SUN APR 13 2014
.UPDATE...
ISSUED AT 1133 PM MDT SUN APR 13 2014
WENT AHEAD AND LET THE WINTER HIGHLIGHTS EXPIRE AT 11 PM THIS
EVENING. LATEST RADAR SHOWING ONLY LIGHT RETURNS WITH THE AERIAL
COVERAGE SHRINKING FAIRLY QUICKLY. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 538 PM MDT SUN APR 13 2014
WENT AHEAD AND EXTENDED WINTER HEADLINES FOR THE I-80 CORRIDOR
THROUGH 11 PM THIS EVENING. HAVE ANOTHER BAND OF SNOW MOVING
NORTHEAST OUT OF COLORADO ON IR IMAGERY. MAY NOT LAST THROUGH 11
PM...BUT IT DOES LOOK LIKE ACCUMULATING SNOW WILL CONTINUE AT
LEAST THROUGH MID EVENING BEFORE EASING SOME. SOME MODEL GUIDANCE
SUGGESTING THAT SNOW COULD LAST LONGER. WILL RE-EVALUATE IN A
COUPLE HOURS. DID GO AHEAD AND EXPIRE OUR NORTHERN WINTER
HEADLINES AS RADAR MOSAIC SHOWING SNOW COVERAGE DECREASING.
UPDATES HAVE BEEN SENT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 240 PM MDT SUN APR 13 2014
SATELLITE PIX SHOW WELL-DEFINED CIRCULATION SPINNING THRU UTAH
WITH A JET STREAK BEGINNING TO ROUND ITS BASE. THE RELATIVE LULL
THIS MORNING ACROSS MUCH OF THE AREA WAS A RESULT OF A BREAK
BETWEEN A DEPARTING SHORTWAVE MOVING INTO THE CENTRAL PLAINS AND
THE NEXT ONE OVR UTAH. AT 20Z...THE NEXT LINE OF ENHANCED CLOUD-
TOPS WERE JUST BEGINNING TO ENTER SRN ALBANY AND LARAMIE
COUNTIES...WITH SIMILAR TRENDS NOTICED ON KCYS 88D RETURNS. SO
WILL SEE SNOW RATES PICK UP AGAIN ESPECIALLY ACROSS EXTREME SE
WYOMING THRU AT LEAST SUNSET. AS WAS FEARED...THE HIGH APRIL SUN-
ANGLE HAS RESULTED IN SUBSTANTIAL MELTING ON AREA ROADWAYS...
WHICH HAS LESSENED IMPACT SOME. HOWEVER A FEW ROAD CLOSURES HAVE
OCCURRED ALONG PORTIONS OF INTERSTATE 80. AN ADDITIONAL 1 TO 3
INCHES OF ACCUMULATION CAN BE EXPECTED THRU EARLY THIS EVENING.
SO WILL KEEP THE HIGHLIGHT PACKAGE UNCHANGED FOR NOW AND CONTINUE
TO RE-EVALUATE TRENDS THRU THE REST OF THE AFTERNOON. LATEST
MODELS CONTINUE TO LINGER SNOW INTO THIS EVENING... HOWEVER RATES
SHOULD BE MUCH LESS AS BEST LIFT SHIFTS SOUTH OUT OF THE CWFA.
ANY LINGERING LIGHT SNOW WILL GRADUALLY END THIS EVENING...WITH
DRYING CONDITIONS THEN OVERNIGHT. OTHERWISE...OVERNIGHT LOWS WILL
FALL INTO THE TEENS ACROSS SOUTHEAST WYOMING...WITH LOW 20S OVR
THE PANHANDLE.
HEIGHTS BUILD RAPIDLY BEHIND THE DEPARTING SHORTWAVE ON
MONDAY...YIELDING DRY AND MOSTLY SUNNY CONDITIONS. NORTHWEST
WINDS WILL BE BREEZY ESPECIALLY OVER THE EASTERN PLAINS WHERE
GUSTS OF 25 TO 30 MPH ARE EXPECTED. TEMPERATURES WILL REBOUND
SOME ON MONDAY TOO...ALTHOUGH WILL BE TEMPERED BY TODAYS SNOW.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 240 PM MDT SUN APR 13 2014
TUESDAY...QUICK WARMUP ON TAP AS OUR FLOW ALOFT BECOMES
ZONAL...WEST TO EAST...AHEAD OF THE PROGRESSIVE LOW AMPLITUDE
SHORTWAVE TROUGH ALOFT OVER MONTANA...AIDING THE DEVELOPMENT OF
SURFACE LOW PRESSURE OVER WESTERN SOUTH DAKOTA...AND PRODUCING
DOWNSLOPE KATABATIC WARMING ACROSS OUR COUNTIES WITH MAXIMUM
TEMPERATURES OVER OUR COUNTIES IN THE 50S WEST OF INTERSTATE
25...AND UPPER 50S TO MID 60S ELSEWHERE.
WEDNESDAY...ANOTHER RELATIVELY STRONG CANADIAN ORIGIN COLD
FRONTAL PASSAGE OCCURS EARLY IN THE DAY...WITH TEMPERATURES LIKELY
STEADY OR SLOWLY FALLING DURING THE DAY. THIS SHORTWAVE TROUGH
WILL NOT HAVE AS MUCH MOISTURE AS OUR CURRENT SUNDAY STORM...AND
LESS MESOSCALE AND DYNAMIC LIFT...THUS 30 TO 60 PERCENT POPS AT
LOWER ELEVATIONS WITH 80 TO 100 PERCENT POPS DUE TO FAVORABLE
OROGRAPHICS OVER THE NORTHERN LARAMIE...SNOWY AND SIERRA MADRE
RANGES.
THURSDAY...DRYING OUT PERIOD IN THE WAKE OF THE SHORTWAVE TROUGH
ALOFT WITH A FEW LEFTOVER SHOWERS OVER THE MOUNTAINS. CONTINUED
RELATIVELY COOL WITH SURFACE HIGH PRESSURE KEEPING THE COLD AIR
REINFORCED OVER THE CENTRAL PLAINS STATES.
FRIDAY...SPRINGTIME IN THE ROCKIES CONTINUES WITH A MILD SPRING
DAY TO END OUR TRADITIONAL WORKWEEK...AS TRANSITORY RIDGING ALOFT
MOVES OVER THE ROCKIES...INDUCING STRENGTHENING SURFACE LEE
TROUGHING AND DOWNSLOPE WARMING AIDING HIGH TEMPERATURES SOARING
INTO THE 50S... AND PERHAPS EVEN WARMER IF THE WARMER ECMWF CAN BE
BELIEVED...AS IT SHOWS 1000-500 MB THICKNESSES NEAR 5640 METERS
WITH 700 MB TEMPERATURES NEAR 7 CELSIUS.
SATURDAY...ANOTHER MILD DAY UNDER NORTHWEST FLOW ALOFT AND
RELATIVELY HIGH THICKNESSES AND 700 MB TEMPERATURES.
SUNDAY...EASTER SUNDAY LOOKS MILD AND DRY WITH NORTHWEST FLOW
ALOFT AND A RIDGE ALOFT OVERHEAD...AND EASTER SUNRISE SERVICES
SHOULD BE PLEASANT FOR OUTDOOR ACTIVITIES WITH MINIMAL CLOUD COVER
AND RELATIVELY MILD TEMPERATURES ABOVE FREEZING TO START THE DAY.
.AVIATION...MOUNTAINS OBSCURED. WIDESPREAD IFR AND MVFR THROUGH
THIS AFTERNOON IN SNOW AND LOW CLOUDS...THEN AREAS OF FOG AND LOW
CLOUDS OVERNIGHT PRODUCING IFR AND MVFR...WITH VFR DEVELOPING LATE
TONIGHT AND MONDAY MORNING FROM NORTH TO SOUTH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY EVENING)
ISSUED AT 1133 PM MDT SUN APR 13 2014
ONLY TROUBLE AIRFIELD AT THIS TIME LOOKS TO BE LARAMIE WITH IFR
VISIBILITIES IN SNOW. THE LATEST HRRR FORECAST HAS IFR CONDITIONS
HANGING IN AROUND KLAR FOR A FEW MORE HOURS BEFORE DISSIPATING
AFTER 10Z OR SO. VFR CONDITIONS ALL AIRPORTS AFTER SUNRISE MONDAY.
&&
.FIRE WEATHER...
ISSUED AT 240 PM MDT SUN APR 13 2014
NO FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK AS FRESH
MOISTURE AND SNOW COVER FROM TODAYS SNOWSTORM LINGERS. SNOW-COVER
WILL ALSO KEEP TEMPERATURES COOLER THROUGH EARLY IN THE
WEEK...WHICH WILL KEEP HUMIDITIES UP. THE NEXT CHANCE OF
PRECIPITATION RETURNS TO THE DISTRICTS ON WEDNESDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...CLAYCOMB
SHORT TERM...HAHN
LONG TERM...RUBIN
AVIATION...CLAYCOMB
FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS MIAMI FL
949 AM EDT MON APR 14 2014
.UPDATE...
A PERSISTENT GROUP OF SHOWERS WILL CONTINUE ACROSS THE LOCAL
ATLANTIC WATERS THIS MORNING. THE INTERACTION OF THE SOUTH-
SOUTHWESTERLY LAND BREEZE AND THE MEAN EASTERLY FLOW COULD HELP IN
THE DEVELOPMENT OF BRIEF WATERSPOUTS WITHIN THIS ACTIVITY. THIS
RISK WILL DECREASE RAPIDLY AS THE LAND BREEZE WEAKENS WITH THE
TEMPERATURE RISING LATE THIS MORNING. LATEST HRRR SHOWS SHOWERS
DEVELOPING THIS AFTERNOON AND EVENING ACROSS THE INTERIOR AND WEST
DUE TO THE INTERACTION OF EASTERLY FLOW AND THE WEST COAST SEA
BREEZE. TEMPERATURES ARE EXPECTED TO REACH THE LOW 90S ACROSS THAT
AREA ALSO #ISMELLSUMMER.
&&
.PREV DISCUSSION... /ISSUED 745 AM EDT MON APR 14 2014/
AVIATION...
MOSTLY VFR CONDITIONS ARE EXPECTED ACROSS SOUTH FLORIDA WITH THE
EXCEPTION OF PERIODIC MVFR CIGS ALONG THE EAST COAST EARLY IN THE
FORECAST AS A FEW SHOWERS MOVE IN FROM THE ATLANTIC, ESPECIALLY
FROM FLL TO PBI. ALSO, IFR CONDITIONS DEVELOPED OVER THE FAR
WESTERN PENINSULA AND ADVECTED OVER THE APF TERMINAL FIELD. THIS
SHOULD BEGIN TO LIFT OUT AFT 13-14Z. SURFACE WIND IS LIGHT E-SE
AND THIS WILL INCREASE TO 10-12KT AFT 14-15Z WITH A SEA BREEZE
DEVELOPING AT APF AROUND 16-17Z.
KOB
PREV DISCUSSION... /ISSUED 241 AM EDT MON APR 14 2014/
.UNSETTLED WEATHER IS EXPECTED THIS WEEK OVER SOUTH FLORIDA...
SHORT TERM...
HIGH PRESSURE WILL CONTINUE TO MOVE FURTHER EAST INTO THE ATLANTIC
WATERS THROUGH TUESDAY ALLOWING FOR A COLD FRONT OVER THE CENTRAL
UNITED STATES TO MOVE SOUTHEAST INTO NORTH FLORIDA. THIS WILL
ALLOW FOR THE WIND FLOW TO SWING FROM AN EASTERLY DIRECTION TODAY
TO A SOUTHERLY DIRECTION ON TUESDAY OVER SOUTH FLORIDA ALLOWING
FOR MOISTURE TO WORK INTO THE AREA LATE TONIGHT INTO TUESDAY.
THEREFORE...THE WEATHER SHOULD REMAIN DRY TODAY INTO TONIGHT OVER
MOST OF SOUTH FLORIDA. THE ONLY EXCEPTION TO THIS IS OVER THE LAKE
OKEECHOBEE REGION AND PALM BEACH COUNTY TODAY WHERE A FEW SHOWERS
COULD DEVELOP DUE TO THE SEA BREEZE AND LAKE BREEZE
COLLISION...AND ALONG THE EAST COAST METRO AREAS TONIGHT. ON
TUESDAY...THERE WILL BE A CHANCE OF SHOWERS OVER MOST OF SOUTH
FLORIDA WITH EVEN SOME THUNDERSTORMS OVER SOUTH FLORIDA.
THE COLD FRONT WILL CONTINUE TO MOVE SOUTHWARD AND THROUGH SOUTH
FLORIDA TUESDAY NIGHT BRINGING IN SOME DRIER WEATHER. THE DRY
WEATHER WILL NOT LAST LONG...AS THE FRONT WILL COME BACK
NORTHWARD LATE WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT AS A WARM
FRONT. SO THE WEATHER OVER SOUTH FLORIDA FOR TUESDAY NIGHT WILL BE
DRY WITH ISOLATED TO SCATTERED SHOWERS FOR WEDNESDAY INTO
WEDNESDAY NIGHT.
LONG TERM...
THE FRONT WILL CONTINUE TO MOVE NORTHWARD INTO CENTRAL FLORIDA
LATE THIS WEEK...AS WEAK LOW PRESSURE DEVELOPS ALONG THE FRONT IN
THE GULF OF MEXICO AND MOVES ACROSS NORTH FLORIDA. THIS WILL ALLOW
FOR MOISTURE TO REMAIN OVER SOUTH FLORIDA LATE THIS WEEK WITH A
CHANCE OF SHOWERS AND EVEN A FEW THUNDERSTORMS.
THE LOW WILL CONTINUE TO MOVE NORTHEAST INTO THE MID ATLANTIC
STATES...AS THE FRONT REMAINS NEARLY STATIONARY OVER NORTH
FLORIDA. THIS WILL KEEP THE LOW LEVEL MOISTURE IN PLACE OVER SOUTH
FLORIDA THIS WEEKEND ALLOWING FOR ISOLATED TO SCATTERED SHOWERS
OVER SOUTH FLORIDA.
MARINE...
THE EASTERLY WINDS TODAY WILL SWING SLOWLY TO A SOUTHERLY DIRECTION
BY TUESDAY...BEFORE GOING NORTHERLY ON WEDNESDAY. THE WIND SPEEDS
WILL BE 15 KNOTS OR LESS TODAY THROUGH WEDNESDAY. THIS WILL KEEP
THE SEAS BELOW 7 FEET IN BOTH THE ATLANTIC AND GULF WATERS THROUGH
WEDNESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 86 74 89 66 / 20 10 50 30
FORT LAUDERDALE 87 75 88 69 / 20 10 30 30
MIAMI 87 75 88 70 / 10 10 30 30
NAPLES 87 72 84 67 / 10 10 40 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...30/KOB
LONG TERM....17/ERA
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
921 AM CDT MON APR 14 2014
.DISCUSSION...
330 AM CDT
THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY
IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS.
THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST
CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL
BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD
LEVELS TONIGHT.
THIS MORNING...
THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO
EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES
60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE
DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING
NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND
MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET
SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR
MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS
SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE
BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT
TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE
VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING.
OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD.
THIS AFTERNOON AND TONIGHT...
A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO
THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING
THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL
NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT
500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA.
GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL
BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS
AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE
MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA
AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND
WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST
TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING
THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS
CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE
TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC
EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY
MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY
AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE
DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO
SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH
HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT
FOLLOWS
BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE
SNOW /FOR GOOD FINALLY?/.
ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS
AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING
LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY
SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A
MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE
BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE.
THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE
PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER
MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING
THANKS TO DECENT SNOWFALL RATES AT TIMES.
TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON
AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION
CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS
WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT
/CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE.
TUESDAY THROUGH THURSDAY...
NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A
CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE
850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE
DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO
MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST
AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR
MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES
GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT
ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES
SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN
ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW
AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT
TIME
FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY
WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING
THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY.
FRIDAY AND BEYOND...
GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN
ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST
INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS
GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH
ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING
LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW GIVEN THE
BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM
A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN
TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND
PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW.
GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE
SOMETIME LATE FRIDAY/THIS WEEKEND.
MTF
&&
.CLIMATE...
625 AM CDT
THE FOLLOWING ARE THE LAST APRIL DATES AND AMOUNTS OF ACCUMULATING
SNOWFALL:
CHICAGO: APRIL 18 2011 (0.6 IN.)
ROCKFORD: APRIL 5 2009 (0.2 IN.)
THE FOLLOWING ARE RECORD LOWS FOR THE MORNING OF APRIL 15TH. THE
CHICAGO ONE IS THE MOST LIKELY IN JEOPARDY.
CHICAGO: 25 (1943)
ROCKFORD: 16 (1928)
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* RAIN/SNOW/SLEET MIX EXITING THIS NEXT HALF HOUR...WITH MVFR
CIGS REMAINING.
* GUSTY N WINDS THROUGH THE DAY...LIKELY TURNING NNE BY EARLY
AFTERNOON.
* SNOW OVERSPREADING THE TERMINALS MID AFTERNOON WITH MINOR
ACCUMULATIONS.
BMD
//DISCUSSION...UPDATED 12Z...
A COLD FRONT IS WORKING ACROSS NORTHEASTERN ILLINOIS EARLY THIS
MORNING WITH WINDS TURNING SHARPLY TO THE NNW WITH GUSTS TO AROUND
30 KT. AREA OBSERVATIONS SHOW A NARROW CORRIDOR OF IFR CIGS IN THE
VICINITY OF THE FRONT...WHICH HAS BEEN SHRINKING OVERNIGHT WITH
PRIMARILY MVFR CIGS EXPECTED THIS MORNING. PRECIP HAS ALSO DWINDLED
AND EXPECTED A COUPLE HOURS OF LIGHT RAIN/DRIZZLE EARLY THIS MORNING
THEN DRY CONDITIONS SHOULD PREVAIL THROUGH AROUND MID AFTERNOON. AT
THAT TIME...AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA
WITH PRECIP OVERSPREADING THE AREA FROM THE SOUTHWEST. RFD MAY BE
CLIPPED BY THIS PRECIP...BUT THE CHICAGO TERMINALS ARE EXPECTED TO
TAKE A MORE DIRECT SHOT. AT THE ONSET...TEMPERATURES MAY BE WARM
ENOUGH FOR A MIX OF RAIN AND SNOW...PARTICULARLY AT MDW AND
GYY...BUT THE COLUMN WILL COOL AND EXPECT A TRANSITION TO ALL SNOW
WITH MINOR ACCUMULATIONS POSSIBLE...ESPECIALLY ON GRASSY SURFACES...
OF UP TO AROUND AND INCH. WINDS SHOULD PRIMARILY REMAIN IN THE
330-360 DIRECTION TODAY WITH GUSTS AROUND 30 KT THIS MORNING VERY
SLOWLY TAPERING THROUGH THE DAY.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* HIGH CONFIDENCE IN PRECIP TIMING AND CIG/VIS TRENDS.
* MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED.
* MEDIUM-HIGH CONFIDENCE IN SNOW TIMING THIS AFTERNOON.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT...VFR.
WEDNESDAY...VFR.
THURSDAY...VFR.
FRIDAY...CHC RAIN. MVFR/IFR PSBL.
SATURDAY...SLT CHC RAIN. MVFR/IFR PSBL.
SUNDAY...CHC RAIN. MVFR/IFR PSBL.
BMD
&&
.MARINE...
240 AM CDT
LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS
MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE
BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO
PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH
TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR
THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD
DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL
TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING
WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN
ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 4
PM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
633 AM CDT MON APR 14 2014
.DISCUSSION...
330 AM CDT
THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY
IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS.
THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST
CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL
BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD
LEVELS TONIGHT.
THIS MORNING...
THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO
EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES
60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE
DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING
NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND
MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET
SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR
MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS
SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE
BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT
TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE
VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING.
OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD.
THIS AFTERNOON AND TONIGHT...
A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO
THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING
THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL
NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT
500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA.
GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL
BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS
AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE
MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA
AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND
WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST
TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING
THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS
CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE
TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC
EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY
MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY
AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE
DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO
SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH
HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT
FOLLOWS
BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE
SNOW /FOR GOOD FINALLY?/.
ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS
AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING
LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY
SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A
MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE
BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE.
THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE
PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER
MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING
THANKS TO DECENT SNOWFALL RATES AT TIMES.
TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON
AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION
CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS
WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT
/CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE.
TUESDAY THROUGH THURSDAY...
NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A
CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE
850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE
DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO
MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST
AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR
MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES
GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT
ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES
SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN
ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW
AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT
TIME
FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY
WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING
THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY.
FRIDAY AND BEYOND...
GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN
ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST
INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS
GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH
ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING
LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW GIVEN THE
BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM
A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN
TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND
PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW.
GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE
SOMETIME LATE FRIDAY/THIS WEEKEND.
MTF
&&
.CLIMATE...
625 AM CDT
THE FOLLOWING ARE THE LAST APRIL DATES AND AMOUNTS OF ACCUMULATING
SNOWFALL:
CHICAGO: APRIL 18 2011 (0.6 IN.)
ROCKFORD: APRIL 5 2009 (0.2 IN.)
THE FOLLOWING ARE RECORD LOWS FOR THE MORNING OF APRIL 15TH. THE
CHICAGO ONE IS THE MOST LIKELY IN JEOPARDY.
CHICAGO: 25 (1943)
ROCKFORD: 16 (1928)
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* FRONT SWEEPING ACROSS THE AREA WITH RAIN/IFR IN THE VICINITY OF
THE FRONT...THEN PRIMARILY MVFR CIGS.
* GUSTY NNW WINDS THROUGH THE DAY.
* SNOW OVERSPREADING THE TERMINALS MID AFTERNOON WITH MINOR
ACCUMULATIONS.
BMD
//DISCUSSION...UPDATED 12Z...
A COLD FRONT IS WORKING ACROSS NORTHEASTERN ILLINOIS EARLY THIS
MORNING WITH WINDS TURNING SHARPLY TO THE NNW WITH GUSTS TO AROUND
30 KT. AREA OBSERVATIONS SHOW A NARROW CORRIDOR OF IFR CIGS IN THE
VICINITY OF THE FRONT...WHICH HAS BEEN SHRINKING OVERNIGHT WITH
PRIMARILY MVFR CIGS EXPECTED THIS MORNING. PRECIP HAS ALSO DWINDLED
AND EXPECTED A COUPLE HOURS OF LIGHT RAIN/DRIZZLE EARLY THIS MORNING
THEN DRY CONDITIONS SHOULD PREVAIL THROUGH AROUND MID AFTERNOON. AT
THAT TIME...AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA
WITH PRECIP OVERSPREADING THE AREA FROM THE SOUTHWEST. RFD MAY BE
CLIPPED BY THIS PRECIP...BUT THE CHICAGO TERMINALS ARE EXPECTED TO
TAKE A MORE DIRECT SHOT. AT THE ONSET...TEMPERATURES MAY BE WARM
ENOUGH FOR A MIX OF RAIN AND SNOW...PARTICULARLY AT MDW AND
GYY...BUT THE COLUMN WILL COOL AND EXPECT A TRANSITION TO ALL SNOW
WITH MINOR ACCUMULATIONS POSSIBLE...ESPECIALLY ON GRASSY SURFACES...
OF UP TO AROUND AND INCH. WINDS SHOULD PRIMARILY REMAIN IN THE
330-360 DIRECTION TODAY WITH GUSTS AROUND 30 KT THIS MORNING VERY
SLOWLY TAPERING THROUGH THE DAY.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM CONFIDENCE IN PRECIP TIMING AND CIG/VIS TRENDS.
* MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED.
* MEDIUM-HIGH CONFIDENCE IN SNOW TIMING THIS AFTERNOON.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT...VFR.
WEDNESDAY...VFR.
THURSDAY...VFR.
FRIDAY...CHC RAIN. MVFR/IFR PSBL.
SATURDAY...SLT CHC RAIN. MVFR/IFR PSBL.
SUNDAY...CHC RAIN. MVFR/IFR PSBL.
BMD
&&
.MARINE...
240 AM CDT
LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS
MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE
BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO
PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH
TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR
THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD
DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL
TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING
WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN
ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 4
PM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
627 AM CDT MON APR 14 2014
.DISCUSSION...
330 AM CDT
THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY
IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS.
THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST
CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL
BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD
LEVELS TONIGHT.
THIS MORNING...
THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO
EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES
60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE
DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING
NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND
MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET
SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR
MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS
SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE
BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT
TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE
VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING.
OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD.
THIS AFTERNOON AND TONIGHT...
A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO
THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING
THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL
NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT
500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA.
GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL
BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS
AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE
MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA
AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND
WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST
TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING
THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS
CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE
TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC
EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY
MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY
AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE
DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO
SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH
HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT
FOLLOWS
BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE
SNOW /FOR GOOD FINALLY?/.
ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS
AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING
LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY
SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A
MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE
BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE.
THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE
PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER
MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING
THANKS TO DECENT SNOWFALL RATES AT TIMES.
TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON
AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION
CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS
WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT
/CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE.
TUESDAY THROUGH THURSDAY...
NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A
CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE
850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE
DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO
MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST
AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR
MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES
GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT
ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES
SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN
ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW
AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT
TIME
FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY
WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING
THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY.
FRIDAY AND BEYOND...
GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN
ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST
INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS
GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH
ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING
LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW GIVEN THE
BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM
A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN
TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND
PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW.
GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE
SOMETIME LATE FRIDAY/THIS WEEKEND.
MTF
&&
.CLIMATE...
625 AM CDT
THE FOLLOWING ARE THE LAST APRIL DATES AND AMOUNTS OF ACCUMULATING
SNOWFALL:
CHICAGO: APRIL 18 2011 (0.6 IN.)
ROCKFORD: APRIL 5 2009 (0.2 IN.)
THE FOLLOWING ARE RECORD LOWS FOR THE MORNING OF APRIL 15TH. THE
CHICAGO ONE IS THE MOST LIKELY IN JEOPARDY.
CHICAGO: 25 (1943)
ROCKFORD: 16 (1928)
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* GUSTY SOUTHERLY WINDS TURNING SHARPLY TO THE NORTH OVERNIGHT
WITH CIGS DROPPING NEAR OR TO IFR.
* OCCASIONAL CHANCES FOR RAIN SHOWERS OVERNIGHT...AND CHANCE FOR
SNOW ACCUMULATIONS DURING THE DAY MONDAY.
BMD
//DISCUSSION...UPDATED 06Z...
LOW PRESSURE LIES NEAR MLI TONIGHT WITH A FRONTAL BOUNDARY EXTENDING
ACROSS FAR NORTHERN ILLINOIS. STRONG SOUTHERLY WINDS ARE OCCURRING
ON THE SOUTH SIDE OF THE FRONT AT THE CHICAGO TERMINALS...BUT AS THE
LOW MOVES EAST OVERNIGHT WINDS WILL TURN SHARPLY TO THE NORTH BEHIND
THE DEPARTING LOW. CIGS WILL DROP TO AROUND 007-010 BEHIND THE FRONT
AND WINDS WILL BECOME QUITE GUSTY...TO AROUND 30 KT OR SO AT TIMES
THROUGH THE MORNING...THEN TAPERING GRADUALLY IN THE AFTERNOON AND
EVENING. ALSO MONDAY AFTERNOON...AN UPPER LEVEL DISTURBANCE MOVING
OVER THE AREA WILL ALLOW PRECIPITATION TO ONCE AGAIN OVERSPREAD THE
TERMINALS. WITH MUCH COLDER AIR IN PLACE TOMORROW...IT DOES APPEAR
MUCH OF THE PRECIP WILL FALL AS SNOW AND CANNOT RULE OUT
ACCUMULATIONS TO AROUND AN INCH. SURFACE TEMPERATURES MAY INITIALLY
MAKE IT DIFFICULT FOR SNOW TO ACCUMULATE...BUT AS SURFACE TEMPS FALL
TO NEAR FREEZING IN THE EVENING CHANCES BECOME A BIT BETTER.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED.
* LOW-MEDIUM CONFIDENCE IN CIGS OVERNIGHT.
* MEDIUM CONFIDENCE IN SNOW TIMING.
BMD
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY THROUGH THURSDAY...PREDOMINANTLY VFR.
FRIDAY...CHANCE OF SHRA.
SATURDAY...VFR PROBABLE.
IZZI
&&
.MARINE...
240 AM CDT
LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS
MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE
BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO
PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH
TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR
THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD
DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL
TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING
WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN
ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 4
PM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS JACKSON KY
1136 AM EDT MON APR 14 2014
.UPDATE...
ISSUED AT 1136 AM EDT MON APR 14 2014
A FEW UPDATES MADE TO THE FORECAST FOR TODAY. BASED ON THE LATEST
SURFACE OBS AND EXPECTED TRENDS...DECIDED TO LOWER TODAYS HOURLY AND
OVERALL HIGH TEMPERATURES BY 3 OR 4 DEGREES ACROSS THE BOARD. WITH
MOIST GROUND...STEADY WINDS...AND PERSISTENT OVERCAST CLOUD
COVER...DID NOT SEEM REASONABLE THAT PREVIOUS IN THE MID TO UPPER 70S
AREA WIDE WERE REACHABLE. THE LATEST RADAR TRENDS AND MODEL
DATA...PARTICULARLY THE HRRR...SEEMED TO SUPPORT THE CURRENT POPS FOR
THE REST OF THE DAY. THE PRECIP CURRENTLY MOVING ACROSS THE AREA
SEEMS TO HAVE A DISTINCT BACK EDGE THAT WILL BE THROUGH OUR AREA IN
THE NEXT FEW HOURS. AFTER THAT IT APPEARS THAT WE WILL SEE A BREAK IN
THE ACTION UNTIL LATER THIS EVENING A COLD FRONT AND UPPER TROUGH
MOVE THROUGH THE AREA. WILL ALSO BE SENDING OUT UPDATED VERSIONS OF
THE LAKE WIND ADVISORY AND FREEZE WATCH. WINDS ACROSS THE AREA SO FAR
TODAY HAVE BEEN MEETING LAKE WIND CRITERIA AND THERE IS NO REASON TO
BELIEVE THIS WILL CEASE TO BE THE CASE THE REST OF THE DAY.
UPDATE ISSUED AT 702 AM EDT MON APR 14 2014
NO UPDATE PLANNED THIS MORNING. LATEST HRRR HAS STUCK TO ITS SCENARIO
TODAY REGARDING SCATTERED LINE OF SHOWERS PUSHING ITS WAY ACROSS THE
AREA TODAY. THESE SHOWERS ARE JUST NOW WORKING INTO THE I-75
CORRIDOR...AND THE CURRENT FORECAST HAS THIS COVERED WELL. NOT SURE
IF WE WILL BE ABLE TO SQUEEZE OUT MUCH LIQUID WITH SUCH DRY AIR
ENTRENCHED ACROSS THE AREA...BUT WE COULD SQUEEZE OUT A HUNDREDTH OR
TWO THROUGH THE MORNING.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT MON APR 14 2014
THERE ARE SEVERAL FEATURES OF INTEREST THIS MORNING UPSTREAM. A WEAK
MID LEVEL TROUGH IS NOW MOVING INTO THE NORTHERN OHIO RIVER VALLEY
WITH A SURFACE LOW PUSHING INTO THE GREAT LAKES REGION. THIS INITIAL
TROUGH HAD BEEN RESPONSIBLE FOR AN ORGANIZED AREA OF SHOWERS AND
STORMS AS IT PUSHED INTO WESTERN KENTUCKY OVERNIGHT. AS THIS
ACTIVITY CONTINUES TO PUSH EAST THIS MORNING IT WILL ENCOUNTER A MUCH
MORE STABLE AND DRY AIR MASS AND WILL QUICKLY WEAKEN. HRRR HAS A GOOD
HANDLE ON THIS AREA OF PRECIPITATION. AS IT REACHES EASTERN
KENTUCKY...IT LOOKS LIKE THE ACTIVITY MAY BECOME MORE SCATTERED AND
EVEN MORE SO AS IT PUSHES FURTHER EAST. WHILE A FASTER ONSET OF
PRECIPITATION LOOKS LIKELY TODAY...IT ALSO LOOKS LIKE ONLY A LIMITED
WINDOW FOR PRECIPITATION THROUGH EARLY AFTERNOON BEFORE WE DRY OUT
AGAIN BY LATE AFTERNOON AND THIS EVENING AS SUBSIDENCE SPREADS BACK
OVER THE AREA AHEAD OF THE NEXT TROUGH. THUS...GOING TO BACK OFF POPS
TO MORE SCATTERED COVERAGE TODAY AS MANY AREAS...ESPECIALLY IN THE
EAST MAY NOT MEASURE TODAY OR WILL LIKELY SEE VERY LIGHT RAINFALL.
WINDS ARE THE OTHER CONCERN FOR TODAY AS WINDS ARE ALREADY GUSTING UP
TO 30 MPH THIS MORNING. WITH THE WEAKENING SHOWERS SPREADING INTO THE
AREA...WE MAY TAP INTO SOME HIGHER WINDS ALOFT WITH 40 KNOTS AROUND
900 MB. THIS MAY CREATE SOME VERY GUSTY CONDITIONS AS THIS BAND OF
SHOWERS MOVES EAST THROUGH EARLY AFTERNOON. THUS...WENT AHEAD AND
ISSUED A LAKE WIND ADVISORY THROUGH 23Z TODAY TO ACCOUNT FOR THESE
WINDS.
MEANWHILE...A SHARPER MID LEVEL TROUGH IS CONTINUING TO DIG OVER THE
CENTRAL ROCKIES WITH A NORTHERN STREAM WAVE PUSHING INTO THE NORTHERN
PLAINS. AS THESE TWO SYSTEMS PHASE AND MOVE EAST...IT WILL ACCELERATE
THE COLD FRONT ACROSS EASTERN KENTUCKY LATE TONIGHT. WITH GOOD
DYNAMICS IN PLACE...AND GOOD CONVERGENCE ALONG THE SURFACE
BOUNDARY...WE WILL SEE WIDESPREAD PRECIPITATION DEVELOP AS THIS
BOUNDARY MOVES EAST. A NARROW RIBBON OF INSTABILITY JUST AHEAD OF THE
FRONT COULD LEND ITSELF TO SOME LIGHTNING OVERNIGHT.
HOWEVER...INSTABILITY SHOULD REMAIN ELEVATED...AND POSE NO SEVERE
THREAT. THE BIGGER STORY WILL BE THE RETURN OF MUCH COLDER AIR INTO
EASTERN KENTUCKY FOR TUESDAY. IT DOES APPEAR SOME MOISTURE WILL
LINGER BEHIND THE COLD FRONT YIELDING AN A BRIEF OPPORTUNITY FOR SOME
SNOW TO MIX IN JUST BEFORE PRECIPITATION ENDS. MOST LOCATIONS WILL
ESCAPE ANY SNOW ACCUMULATION AS THE GROUND WILL SIMPLY BE TOO WARM.
THE EXCEPTION WILL BE IN THE HIGHEST TERRAIN ABOVE 2.5KFT AS COLDER
SURFACE TEMPERATURES MAY ALLOW FOR BETTER ACCUMULATION POTENTIAL.
WILL GO WITH UP TO 2 INCHES ON THE HIGHEST PEAKS IN SOUTHEAST
KENTUCKY. PRECIPITATION WILL COME TO AN END THROUGH THE DAY
TUESDAY...BUT SOME DRIZZLE OR FLURRIES COULD LINGER ACROSS THE HIGH
TERRAIN IN THE SOUTHEAST INTO THE AFTERNOON OR EVENING HOURS. HIGHS
WILL STRUGGLE TO REACH 40 ON TUESDAY...WITH HIGHS POSSIBLY OCCURRING
EARLY IN THE DAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 449 AM EDT MON APR 14 2014
A SURFACE RIDGE WILL BE MOVING OVER THE AREA WITH AN UNSEASONABLY
COLD AND DRY AIR MASS AT THE START OF THE PERIOD. MODELS HAVE BEEN
CONSISTENT IN THEIR SOLUTIONS...AGREEING ON CLEARING SKIES AND EASING
WINDS LEADING TO A HARD FREEZE FOR MOST LOCATIONS...AND A FREEZE
WATCH HAS BEEN ISSUED FOR TUESDAY NIGHT INTO WEDNESDAY MORNING. THE
HIGH WILL SLIP TO OUR EAST WEDNESDAY AND THURSDAY...AND WEAK WARM AIR
ADVECTION WILL RETURN. MOISTURE WILL BE SLOW TO INCREASE...SO EVEN
THOUGH AFTERNOONS WILL BE MILDER...CLEAR TO PARTLY CLOUDY SKIES WILL
ALLOW FOR A LARGE DIURNAL RANGE WITH CHILLY EARLY MORNINGS. FROST
WILL BE EXPECTED FOR MANY LOCATIONS ON WEDNESDAY NIGHT...AND POSSIBLY
ON THURSDAY NIGHT IN THE COLDEST VALLEYS.
FROM FRIDAY THROUGH THE WEEKEND THE MODELS BECOME MORE DISPARATE AS
TIME GOES BY. IN GENERAL TERMS...ANOTHER MID/UPPER LEVEL TROUGH WILL
PROGRESS EAST ACROSS THE CONUS. COMPARED TO THE GFS...THE ECMWF IS
STRONGER WITH THE SOUTHERN END OF THIS FEATURE NEAR THE GULF COAST.
MEANWHILE...THE GFS IS WEAKER NEAR THE GULF COAST...BUT MUCH MORE
AMPLIFIED ACROSS THE NORTH CENTRAL CONUS. THIS AFFECTS CORRESPONDING
SURFACE LOW DEVELOPMENT. BOTH SCENARIOS BRING THE GREATEST POP ON
FRIDAY NIGHT...BUT THE GFS IS MORE SUPPORTIVE OF PRECIP. THE
DIFFERING SURFACE PATTERNS ALSO AFFECT HOW MUCH COLDER FLOWS
SOUTHWARD DURING THE WEEKEND. SOME MEMBERS OF THE GFS ENSEMBLE VARY
QUITE A BIT FROM THE OPERATIONAL RUN...AND LEND SUPPORT TO THE ECMWF
PATTERN...BUT THE GFS ENSEMBLE MEAN SUPPORTS THE OPERATIONAL GFS.
WITH ALL THIS IN MIND...WILL CONTINUE TO USE A GENERALIZED MODEL
COMPROMISE...WITH A LOWER CONFIDENCE THAN NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 702 AM EDT MON APR 14 2014
MAINLY VFR CONDITIONS WILL LIKELY PERSIST THROUGH THIS EVENING. .
THE MAIN AVIATION CONCERN TODAY WILL BE GUSTY SOUTH AS THEY COULD
REACH AROUND 30 KNOTS AT TIMES THROUGH THE DAY. A FEW ISOLATED HIGHER
WIND GUSTS COULD ALSO BE POSSIBLE IN AND AROUND SHOWERS WHICH WILL BE
SPREADING ACROSS THE AREA TODAY. A SHARP WIND SHIFT IS ANTICIPATED
TONIGHT AS A COLD FRONT PUSHES ACROSS EASTERN KENTUCKY. THIS WIND
SHIFT WILL LIKELY OCCUR CLOSER TO MIDNIGHT OR LATER AS WINDS GO FROM
THE SOUTH TO THE WEST AND NORTHWEST. IN ADDITION...WIDESPREAD
PRECIPITATION WILL OVERSPREAD THE AREA LATE TONIGHT WITH CIGS COMING
DOWN LATE TONIGHT TO MVFR OR LOWER.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY MORNING FOR
KYZ044-050>052-058>060-068-069-079-080-083>088-104-106>120.
LAKE WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR KYZ044-
050>052-058>060-068-069-079-080-083>088-104-106>120.
&&
$$
UPDATE...AR
SHORT TERM...KAS
LONG TERM...HAL
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
703 AM EDT MON APR 14 2014
.UPDATE...
ISSUED AT 702 AM EDT MON APR 14 2014
NO UPDATE PLANNED THIS MORNING. LATEST HRRR HAS STUCK TO ITS SCENARIO
TODAY REGARDING SCATTERED LINE OF SHOWERS PUSHING ITS WAY ACROSS THE
AREA TODAY. THESE SHOWERS ARE JUST NOW WORKING INTO THE I-75
CORRIDOR...AND THE CURRENT FORECAST HAS THIS COVERED WELL. NOT SURE
IF WE WILL BE ABLE TO SQUEEZE OUT MUCH LIQUID WITH SUCH DRY AIR
ENTRENCHED ACROSS THE AREA...BUT WE COULD SQUEEZE OUT A HUNDREDTH OR
TWO THROUGH THE MORNING.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT MON APR 14 2014
THERE ARE SEVERAL FEATURES OF INTEREST THIS MORNING UPSTREAM. A WEAK
MID LEVEL TROUGH IS NOW MOVING INTO THE NORTHERN OHIO RIVER VALLEY
WITH A SURFACE LOW PUSHING INTO THE GREAT LAKES REGION. THIS INITIAL
TROUGH HAD BEEN RESPONSIBLE FOR AN ORGANIZED AREA OF SHOWERS AND
STORMS AS IT PUSHED INTO WESTERN KENTUCKY OVERNIGHT. AS THIS
ACTIVITY CONTINUES TO PUSH EAST THIS MORNING IT WILL ENCOUNTER A MUCH
MORE STABLE AND DRY AIR MASS AND WILL QUICKLY WEAKEN. HRRR HAS A GOOD
HANDLE ON THIS AREA OF PRECIPITATION. AS IT REACHES EASTERN
KENTUCKY...IT LOOKS LIKE THE ACTIVITY MAY BECOME MORE SCATTERED AND
EVEN MORE SO AS IT PUSHES FURTHER EAST. WHILE A FASTER ONSET OF
PRECIPITATION LOOKS LIKELY TODAY...IT ALSO LOOKS LIKE ONLY A LIMITED
WINDOW FOR PRECIPITATION THROUGH EARLY AFTERNOON BEFORE WE DRY OUT
AGAIN BY LATE AFTERNOON AND THIS EVENING AS SUBSIDENCE SPREADS BACK
OVER THE AREA AHEAD OF THE NEXT TROUGH. THUS...GOING TO BACK OFF POPS
TO MORE SCATTERED COVERAGE TODAY AS MANY AREAS...ESPECIALLY IN THE
EAST MAY NOT MEASURE TODAY OR WILL LIKELY SEE VERY LIGHT RAINFALL.
WINDS ARE THE OTHER CONCERN FOR TODAY AS WINDS ARE ALREADY GUSTING UP
TO 30 MPH THIS MORNING. WITH THE WEAKENING SHOWERS SPREADING INTO THE
AREA...WE MAY TAP INTO SOME HIGHER WINDS ALOFT WITH 40 KNOTS AROUND
900 MB. THIS MAY CREATE SOME VERY GUSTY CONDITIONS AS THIS BAND OF
SHOWERS MOVES EAST THROUGH EARLY AFTERNOON. THUS...WENT AHEAD AND
ISSUED A LAKE WIND ADVISORY THROUGH 23Z TODAY TO ACCOUNT FOR THESE
WINDS.
MEANWHILE...A SHARPER MID LEVEL TROUGH IS CONTINUING TO DIG OVER THE
CENTRAL ROCKIES WITH A NORTHERN STREAM WAVE PUSHING INTO THE NORTHERN
PLAINS. AS THESE TWO SYSTEMS PHASE AND MOVE EAST...IT WILL ACCELERATE
THE COLD FRONT ACROSS EASTERN KENTUCKY LATE TONIGHT. WITH GOOD
DYNAMICS IN PLACE...AND GOOD CONVERGENCE ALONG THE SURFACE
BOUNDARY...WE WILL SEE WIDESPREAD PRECIPITATION DEVELOP AS THIS
BOUNDARY MOVES EAST. A NARROW RIBBON OF INSTABILITY JUST AHEAD OF THE
FRONT COULD LEND ITSELF TO SOME LIGHTNING OVERNIGHT.
HOWEVER...INSTABILITY SHOULD REMAIN ELEVATED...AND POSE NO SEVERE
THREAT. THE BIGGER STORY WILL BE THE RETURN OF MUCH COLDER AIR INTO
EASTERN KENTUCKY FOR TUESDAY. IT DOES APPEAR SOME MOISTURE WILL
LINGER BEHIND THE COLD FRONT YIELDING AN A BRIEF OPPORTUNITY FOR SOME
SNOW TO MIX IN JUST BEFORE PRECIPITATION ENDS. MOST LOCATIONS WILL
ESCAPE ANY SNOW ACCUMULATION AS THE GROUND WILL SIMPLY BE TOO WARM.
THE EXCEPTION WILL BE IN THE HIGHEST TERRAIN ABOVE 2.5KFT AS COLDER
SURFACE TEMPERATURES MAY ALLOW FOR BETTER ACCUMULATION POTENTIAL.
WILL GO WITH UP TO 2 INCHES ON THE HIGHEST PEAKS IN SOUTHEAST
KENTUCKY. PRECIPITATION WILL COME TO AN END THROUGH THE DAY
TUESDAY...BUT SOME DRIZZLE OR FLURRIES COULD LINGER ACROSS THE HIGH
TERRAIN IN THE SOUTHEAST INTO THE AFTERNOON OR EVENING HOURS. HIGHS
WILL STRUGGLE TO REACH 40 ON TUESDAY...WITH HIGHS POSSIBLY OCCURRING
EARLY IN THE DAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 449 AM EDT MON APR 14 2014
A SURFACE RIDGE WILL BE MOVING OVER THE AREA WITH AN UNSEASONABLY
COLD AND DRY AIR MASS AT THE START OF THE PERIOD. MODELS HAVE BEEN
CONSISTENT IN THEIR SOLUTIONS...AGREEING ON CLEARING SKIES AND EASING
WINDS LEADING TO A HARD FREEZE FOR MOST LOCATIONS...AND A FREEZE
WATCH HAS BEEN ISSUED FOR TUESDAY NIGHT INTO WEDNESDAY MORNING. THE
HIGH WILL SLIP TO OUR EAST WEDNESDAY AND THURSDAY...AND WEAK WARM AIR
ADVECTION WILL RETURN. MOISTURE WILL BE SLOW TO INCREASE...SO EVEN
THOUGH AFTERNOONS WILL BE MILDER...CLEAR TO PARTLY CLOUDY SKIES WILL
ALLOW FOR A LARGE DIURNAL RANGE WITH CHILLY EARLY MORNINGS. FROST
WILL BE EXPECTED FOR MANY LOCATIONS ON WEDNESDAY NIGHT...AND POSSIBLY
ON THURSDAY NIGHT IN THE COLDEST VALLEYS.
FROM FRIDAY THROUGH THE WEEKEND THE MODELS BECOME MORE DISPARATE AS
TIME GOES BY. IN GENERAL TERMS...ANOTHER MID/UPPER LEVEL TROUGH WILL
PROGRESS EAST ACROSS THE CONUS. COMPARED TO THE GFS...THE ECMWF IS
STRONGER WITH THE SOUTHERN END OF THIS FEATURE NEAR THE GULF COAST.
MEANWHILE...THE GFS IS WEAKER NEAR THE GULF COAST...BUT MUCH MORE
AMPLIFIED ACROSS THE NORTH CENTRAL CONUS. THIS AFFECTS CORRESPONDING
SURFACE LOW DEVELOPMENT. BOTH SCENARIOS BRING THE GREATEST POP ON
FRIDAY NIGHT...BUT THE GFS IS MORE SUPPORTIVE OF PRECIP. THE
DIFFERING SURFACE PATTERNS ALSO AFFECT HOW MUCH COLDER FLOWS
SOUTHWARD DURING THE WEEKEND. SOME MEMBERS OF THE GFS ENSEMBLE VARY
QUITE A BIT FROM THE OPERATIONAL RUN...AND LEND SUPPORT TO THE ECMWF
PATTERN...BUT THE GFS ENSEMBLE MEAN SUPPORTS THE OPERATIONAL GFS.
WITH ALL THIS IN MIND...WILL CONTINUE TO USE A GENERALIZED MODEL
COMPROMISE...WITH A LOWER CONFIDENCE THAN NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 702 AM EDT MON APR 14 2014
MAINLY VFR CONDITIONS WILL LIKELY PERSIST THROUGH THIS EVENING. .
THE MAIN AVIATION CONCERN TODAY WILL BE GUSTY SOUTH AS THEY COULD
REACH AROUND 30 KNOTS AT TIMES THROUGH THE DAY. A FEW ISOLATED HIGHER
WIND GUSTS COULD ALSO BE POSSIBLE IN AND AROUND SHOWERS WHICH WILL BE
SPREADING ACROSS THE AREA TODAY. A SHARP WIND SHIFT IS ANTICIPATED
TONIGHT AS A COLD FRONT PUSHES ACROSS EASTERN KENTUCKY. THIS WIND
SHIFT WILL LIKELY OCCUR CLOSER TO MIDNIGHT OR LATER AS WINDS GO FROM
THE SOUTH TO THE WEST AND NORTHWEST. IN ADDITION...WIDESPREAD
PRECIPITATION WILL OVERSPREAD THE AREA LATE TONIGHT WITH CIGS COMING
DOWN LATE TONIGHT TO MVFR OR LOWER.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY MORNING FOR
KYZ044-050>052-058>060-068-069-079-080-083>088-104-106>120.
LAKE WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR KYZ044-
050>052-058>060-068-069-079-080-083>088-104-106>120.
&&
$$
UPDATE...KAS
SHORT TERM...KAS
LONG TERM...HAL
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1050 AM CDT MON APR 14 2014
.DISCUSSION...
STORM INTENSITIES ARE INCREASING...WITH ADDITIONAL CONVECTIVE
DEVELOPMENT UPSTREAM...PROMPTING A SEVERE TSTM WATCH THRU 5
PM...FOR HAIL. NO DAMAGING WINDS EXPECTED./VII/
&&
.PREV DISCUSSION... /ISSUED 949 AM CDT MON APR 14 2014/
DISCUSSION...
BOTH PREFRONTAL AND POSTFRONTAL CONVECTION INCREASING ACROSS
AREA...WITH STG COLD FRONT BISECTING THE REGION. EXPECT INCREASING
TSTM ACTIVITY ALONG COLD FRONT TO POSSIBLY PRODUCE SMALL HAIL.
THIS FRONT WILL MOVE ACROSS SOUTHERN CWA BY MIDDAY. SMALL SHOWERS
ALSO INCREASING IN COVERAGE ACROSS EXTREME NORTHERN CWA...SO
RAISED POPS BACK UP INTO CHANCE CATEGORY./VII/
PREV DISCUSSION... /ISSUED 705 AM CDT MON APR 14 2014/
AVIATION...
12Z SFC ANALYSIS HAS THE COLD FRONT THROUGH THE TYR...TXK
TERMINALS AND ALMOST ON TOP OF THE GGG TERMINAL. THE FRONT
CONTINUES TO MAKE SLOW BUT STEADY PROGRESS TO THE SOUTH AND EAST
THIS MORNING. AHEAD OF THE FRONT...REMNANT OUTFLOW BOUNDARY EXISTS
FROM NEAR LFK TO MLU AND THIS FEATURE CONTINUES TO MOVE SLOWLY
SOUTH AND EAST AS WELL. NEW STRONG TO SEVERE CONVECTION IS
DEVELOPING JUST AHEAD OF THE FRONT BUT BEHIND THE OUTFLOW BOUNDARY
ACROSS PORTIONS OF EAST CENTRAL TEXAS ATTM. CEILINGS DIRECTLY
BEHIND THE FRONT GO TO BRIEF IFR CONDITIONS BUT THEN BECOME MVFR
WHILE CEILINGS AHEAD OF THE FRONT ARE MOSTLY MVFR.
FOR THE TERMINAL PACKAGE TODAY...PREVAILED MVFR CEILINGS THROUGH
MUCH OF THE DAY WITH VCSH AND/OR VCTS MENTION. LATEST HRRR DATA
SUGGEST THE POTENTIAL FOR POST FRONTAL SHOWERS TO MADE MENTION OF
THIS AS WELL. STRONG PRESSURE GRADIENT IN THE WAKE OF THE FRONTAL
BOUNDARY AND THUS...EXPECT SUSTAINED POST FRONTAL WINDS OF 14-18KTS
WITH GUSTS APPROACHING 30KTS. WINDS WILL DECOUPLE LATE THIS EVENING
AND EXPECTING CLEARING FROM WEST TO EAST OVERNIGHT AS WELL.
/13/
PREV DISCUSSION... /ISSUED 552 AM CDT MON APR 14 2014/
DISCUSSION...
A BUSY MORNING TO SAY THE LEAST WITH VARIOUS ELEMENTS TO CONTEND
WITH AS IT RELATES TO WWA CRITERIA SO APOLOGIZE FOR THE BELATED
DISCUSSION. FIRST THINGS FIRST...ALL CONVECTIVE WATCHES HAVE
EITHER EXPIRED OR BEEN DROPPED FOR OUR REGION AS WIDESPREAD SEVERE
THREAT NEVER REALLY MATERIALIZED AS INITIALLY ANTICIPATED DUE
PRIMARILY TO THE LACK OF INSTABILITY BUT ALSO SIGNIFICANT DRY
SLOTTING WHICH WAS NOT EXACTLY FORESEEN. ALL THIS TO SAY THAT
ALTHOUGH A SIGNIFICANT SEVERE EVENT DID NOT MATERIALIZE...A FEW
ISOLD SEVERE STORMS DID PRODUCE SOME DAMAGING WIND GUSTS OVER
EXTREME SW ARKANSAS AND ONE POSSIBLE TORNADO OVER NE TX LATE
SUNDAY.
NOW SHIFTING GEARS TO THE ACTUAL COLD FRONT AND POST-FRONTAL
CONDITIONS...THE FRONT ITSELF WAS LOCATED ALONG A PBF...TXK...CRS
LINE AS OF 10Z THIS MORNING GENERALLY SPLITTING OUR CWA IN HALF.
CONVECTION CONTINUES OUT AHEAD OF THE FRONT WITH MAINLY LIGHT TO
MODERATE SHWRS AND A FEW EMBEDDED TSTMS EXTENDING FROM S CNTRL AR
BACK OVER MUCH OF N LA AND LOWER E TX. BEHIND THE FRONT...GUSTY NW
WINDS AND SHARPLY COOLER TEMPERATURES ARE FOUND OVER SE OK AND
EXTREME NE TX. THE VERY TIGHT PRESSURE GRADIENT HAS PROMPTED A
LAKE WIND ADVISORY AREA WIDE FOR TODAY...ALBEIT STARTING A BIT
LATER ACROSS OUR SERN HALF AS CONDITIONS WILL NOT BE MET OVER
THESE AREAS UNTIL AROUND MIDDAY AND PERSISTING THROUGH MIDNIGHT.
THE NEXT DILEMMA IS DETERMINING HOW FAR TEMPERATURES WILL FALL
LATER TONIGHT INTO TUESDAY MORNING AND IF WE SEE NEAR FREEZING OR
EVEN SUB-FREEZING READINGS...HOW FAR SOUTH WILL THEY MAKE IT. THE
BEST HACK FOR NOW IS SE OK...ALL OF OUR NRN TIER AR COUNTIES AND
POSSIBLY RED RIVER COUNTY IN NE TX. HAVE GONE AHEAD AND ISSUED A
FREEZE WARNING FOR THESE AREAS TO BEGIN AFTER MIDNIGHT AND LASTING
THROUGH LATE MORNING ON TUESDAY. ALTHOUGH THE DURATION SEEMS A BIT
LONGER THAN WHAT MAY ACTUALLY OCCUR...WANTED TO MAKE SURE WE ARE
COVERED ON EITHER SIDE IN CASE THE AIR MASS IS EVEN COLDER THAN
CURRENTLY FORECAST. A FEW OTHER NOTES WORTH MENTIONING INCLUDE
WIND CHILLS IN THE 20S AND 30S OVERNIGHT INTO TUESDAY MORNING EVEN
WITH THE WINDS DECREASING SLIGHTLY AFTER MIDNIGHT. THE THREAT OF
FREEZING TEMPERATURES OVER THESE SAME AREAS WILL BE POSSIBLE
ONCE AGAIN ON WEDNESDAY MORNING AND MAYBE A FEW LOCATIONS FARTHER
SOUTH IN SRN AR/NRN LA SO WILL NEED TO MONITOR FOR ADDITIONAL FREEZE
WARNINGS.
TEMPERATURES WILL GRADUALLY MODERATE THROUGH THE REMAINDER OF THE
WEEK AND GENERALLY RUN NEAR SEASONAL AVERAGES WITH ANOTHER CHANCE
OF SHWRS AND TSTMS RETURNING LATE THURSDAY INTO FRIDAY WITH THE
ARRIVAL OF OUR NEXT COLD FRONT. THE WEEKEND LOOKS MIXED WITH A
BRIEF BREAK FROM THE RAIN EARLY SATURDAY BUT THEN RETURNING BY
LATE SATURDAY AND ESPECIALLY SUNDAY WITH AN UPPER LEVEL
DISTURBANCE SHIFTING ACROSS THE REGION FROM THE SW TX. /19/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 67 36 60 36 68 / 40 20 0 0 0
MLU 70 36 60 33 67 / 40 40 0 0 0
DEQ 55 30 60 32 66 / 30 10 0 0 0
TXK 58 34 60 36 66 / 30 10 0 0 0
ELD 65 33 60 32 66 / 40 30 0 0 0
TYR 58 34 61 36 68 / 40 10 0 0 0
GGG 62 34 61 34 68 / 40 10 0 0 0
LFK 70 36 63 34 69 / 50 20 0 0 0
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING
ZONES: ARZ060-061-071>073.
LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING
ZONES: ARZ050-051-059-070.
FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING
ZONES: ARZ050-051-059>061.
LA...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING
ZONES: LAZ001>006-010>014-017>022.
OK...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING
ZONES: OKZ077.
FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING
ZONES: OKZ077.
TX...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING
ZONES: TXZ152-153-165>167.
LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING
ZONES: TXZ096-097-108>112-124>126-136>138-149>151.
FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING
ZONES: TXZ096.
&&
$$
VII
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
949 AM CDT MON APR 14 2014
.DISCUSSION...
BOTH PREFRONTAL AND POSTFRONTAL CONVECTION INCREASING ACROSS
AREA...WITH STG COLD FRONT BISECTING THE REGION. EXPECT INCREASING
TSTM ACTIVITY ALONG COLD FRONT TO POSSIBLY PRODUCE SMALL HAIL.
THIS FRONT WILL MOVE ACROSS SOUTHERN CWA BY MIDDAY. SMALL SHOWERS
ALSO INCREASING IN COVERAGE ACROSS EXTREME NORTHERN CWA...SO
RAISED POPS BACK UP INTO CHANCE CATEGORY./VII/
&&
.PREV DISCUSSION... /ISSUED 705 AM CDT MON APR 14 2014/
AVIATION...
12Z SFC ANALYSIS HAS THE COLD FRONT THROUGH THE TYR...TXK
TERMINALS AND ALMOST ON TOP OF THE GGG TERMINAL. THE FRONT
CONTINUES TO MAKE SLOW BUT STEADY PROGRESS TO THE SOUTH AND EAST
THIS MORNING. AHEAD OF THE FRONT...REMNANT OUTFLOW BOUNDARY EXISTS
FROM NEAR LFK TO MLU AND THIS FEATURE CONTINUES TO MOVE SLOWLY
SOUTH AND EAST AS WELL. NEW STRONG TO SEVERE CONVECTION IS
DEVELOPING JUST AHEAD OF THE FRONT BUT BEHIND THE OUTFLOW BOUNDARY
ACROSS PORTIONS OF EAST CENTRAL TEXAS ATTM. CEILINGS DIRECTLY
BEHIND THE FRONT GO TO BRIEF IFR CONDITIONS BUT THEN BECOME MVFR
WHILE CEILINGS AHEAD OF THE FRONT ARE MOSTLY MVFR.
FOR THE TERMINAL PACKAGE TODAY...PREVAILED MVFR CEILINGS THROUGH
MUCH OF THE DAY WITH VCSH AND/OR VCTS MENTION. LATEST HRRR DATA
SUGGEST THE POTENTIAL FOR POST FRONTAL SHOWERS TO MADE MENTION OF
THIS AS WELL. STRONG PRESSURE GRADIENT IN THE WAKE OF THE FRONTAL
BOUNDARY AND THUS...EXPECT SUSTAINED POST FRONTAL WINDS OF 14-18KTS
WITH GUSTS APPROACHING 30KTS. WINDS WILL DECOUPLE LATE THIS EVENING
AND EXPECTING CLEARING FROM WEST TO EAST OVERNIGHT AS WELL.
/13/
PREV DISCUSSION... /ISSUED 552 AM CDT MON APR 14 2014/
DISCUSSION...
A BUSY MORNING TO SAY THE LEAST WITH VARIOUS ELEMENTS TO CONTEND
WITH AS IT RELATES TO WWA CRITERIA SO APOLOGIZE FOR THE BELATED
DISCUSSION. FIRST THINGS FIRST...ALL CONVECTIVE WATCHES HAVE
EITHER EXPIRED OR BEEN DROPPED FOR OUR REGION AS WIDESPREAD SEVERE
THREAT NEVER REALLY MATERIALIZED AS INITIALLY ANTICIPATED DUE
PRIMARILY TO THE LACK OF INSTABILITY BUT ALSO SIGNIFICANT DRY
SLOTTING WHICH WAS NOT EXACTLY FORESEEN. ALL THIS TO SAY THAT
ALTHOUGH A SIGNIFICANT SEVERE EVENT DID NOT MATERIALIZE...A FEW
ISOLD SEVERE STORMS DID PRODUCE SOME DAMAGING WIND GUSTS OVER
EXTREME SW ARKANSAS AND ONE POSSIBLE TORNADO OVER NE TX LATE
SUNDAY.
NOW SHIFTING GEARS TO THE ACTUAL COLD FRONT AND POST-FRONTAL
CONDITIONS...THE FRONT ITSELF WAS LOCATED ALONG A PBF...TXK...CRS
LINE AS OF 10Z THIS MORNING GENERALLY SPLITTING OUR CWA IN HALF.
CONVECTION CONTINUES OUT AHEAD OF THE FRONT WITH MAINLY LIGHT TO
MODERATE SHWRS AND A FEW EMBEDDED TSTMS EXTENDING FROM S CNTRL AR
BACK OVER MUCH OF N LA AND LOWER E TX. BEHIND THE FRONT...GUSTY NW
WINDS AND SHARPLY COOLER TEMPERATURES ARE FOUND OVER SE OK AND
EXTREME NE TX. THE VERY TIGHT PRESSURE GRADIENT HAS PROMPTED A
LAKE WIND ADVISORY AREA WIDE FOR TODAY...ALBEIT STARTING A BIT
LATER ACROSS OUR SERN HALF AS CONDITIONS WILL NOT BE MET OVER
THESE AREAS UNTIL AROUND MIDDAY AND PERSISTING THROUGH MIDNIGHT.
THE NEXT DILEMMA IS DETERMINING HOW FAR TEMPERATURES WILL FALL
LATER TONIGHT INTO TUESDAY MORNING AND IF WE SEE NEAR FREEZING OR
EVEN SUB-FREEZING READINGS...HOW FAR SOUTH WILL THEY MAKE IT. THE
BEST HACK FOR NOW IS SE OK...ALL OF OUR NRN TIER AR COUNTIES AND
POSSIBLY RED RIVER COUNTY IN NE TX. HAVE GONE AHEAD AND ISSUED A
FREEZE WARNING FOR THESE AREAS TO BEGIN AFTER MIDNIGHT AND LASTING
THROUGH LATE MORNING ON TUESDAY. ALTHOUGH THE DURATION SEEMS A BIT
LONGER THAN WHAT MAY ACTUALLY OCCUR...WANTED TO MAKE SURE WE ARE
COVERED ON EITHER SIDE IN CASE THE AIR MASS IS EVEN COLDER THAN
CURRENTLY FORECAST. A FEW OTHER NOTES WORTH MENTIONING INCLUDE
WIND CHILLS IN THE 20S AND 30S OVERNIGHT INTO TUESDAY MORNING EVEN
WITH THE WINDS DECREASING SLIGHTLY AFTER MIDNIGHT. THE THREAT OF
FREEZING TEMPERATURES OVER THESE SAME AREAS WILL BE POSSIBLE
ONCE AGAIN ON WEDNESDAY MORNING AND MAYBE A FEW LOCATIONS FARTHER
SOUTH IN SRN AR/NRN LA SO WILL NEED TO MONITOR FOR ADDITIONAL FREEZE
WARNINGS.
TEMPERATURES WILL GRADUALLY MODERATE THROUGH THE REMAINDER OF THE
WEEK AND GENERALLY RUN NEAR SEASONAL AVERAGES WITH ANOTHER CHANCE
OF SHWRS AND TSTMS RETURNING LATE THURSDAY INTO FRIDAY WITH THE
ARRIVAL OF OUR NEXT COLD FRONT. THE WEEKEND LOOKS MIXED WITH A
BRIEF BREAK FROM THE RAIN EARLY SATURDAY BUT THEN RETURNING BY
LATE SATURDAY AND ESPECIALLY SUNDAY WITH AN UPPER LEVEL
DISTURBANCE SHIFTING ACROSS THE REGION FROM THE SW TX. /19/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 67 36 60 36 68 / 40 20 0 0 0
MLU 70 36 60 33 67 / 60 40 0 0 0
DEQ 55 30 60 32 66 / 30 10 0 0 0
TXK 58 34 60 36 66 / 30 10 0 0 0
ELD 65 33 60 32 66 / 40 30 0 0 0
TYR 58 34 61 36 68 / 40 10 0 0 0
GGG 62 34 61 34 68 / 40 10 0 0 0
LFK 70 36 63 34 69 / 50 20 0 0 0
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING
ZONES: ARZ060-061-071>073.
LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING
ZONES: ARZ050-051-059-070.
FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING
ZONES: ARZ050-051-059>061.
LA...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING
ZONES: LAZ001>006-010>014-017>022.
OK...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING
ZONES: OKZ077.
FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING
ZONES: OKZ077.
TX...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING
ZONES: TXZ152-153-165>167.
LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING
ZONES: TXZ096-097-108>112-124>126-136>138-149>151.
FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING
ZONES: TXZ096.
&&
$$
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
705 AM CDT MON APR 14 2014
.AVIATION...
12Z SFC ANALYSIS HAS THE COLD FRONT THROUGH THE TYR...TXK
TERMINALS AND ALMOST ON TOP OF THE GGG TERMINAL. THE FRONT
CONTINUES TO MAKE SLOW BUT STEADY PROGRESS TO THE SOUTH AND EAST
THIS MORNING. AHEAD OF THE FRONT...REMNANT OUTFLOW BOUNDARY EXISTS
FROM NEAR LFK TO MLU AND THIS FEATURE CONTINUES TO MOVE SLOWLY
SOUTH AND EAST AS WELL. NEW STRONG TO SEVERE CONVECTION IS
DEVELOPING JUST AHEAD OF THE FRONT BUT BEHIND THE OUTFLOW BOUNDARY
ACROSS PORTIONS OF EAST CENTRAL TEXAS ATTM. CEILINGS DIRECTLY
BEHIND THE FRONT GO TO BRIEF IFR CONDITIONS BUT THEN BECOME MVFR
WHILE CEILINGS AHEAD OF THE FRONT ARE MOSTLY MVFR.
FOR THE TERMINAL PACKAGE TODAY...PREVAILED MVFR CEILINGS THROUGH
MUCH OF THE DAY WITH VCSH AND/OR VCTS MENTION. LATEST HRRR DATA
SUGGEST THE POTENTIAL FOR POST FRONTAL SHOWERS TO MADE MENTION OF
THIS AS WELL. STRONG PRESSURE GRADIENT IN THE WAKE OF THE FRONTAL
BOUNDARY AND THUS...EXPECT SUSTAINED POST FRONTAL WINDS OF 14-18KTS
WITH GUSTS APPROACHING 30KTS. WINDS WILL DECOUPLE LATE THIS EVENING
AND EXPECTING CLEARING FROM WEST TO EAST OVERNIGHT AS WELL.
/13/
&&
.PREV DISCUSSION... /ISSUED 552 AM CDT MON APR 14 2014/
DISCUSSION...
A BUSY MORNING TO SAY THE LEAST WITH VARIOUS ELEMENTS TO CONTEND
WITH AS IT RELATES TO WWA CRITERIA SO APOLOGIZE FOR THE BELATED
DISCUSSION. FIRST THINGS FIRST...ALL CONVECTIVE WATCHES HAVE
EITHER EXPIRED OR BEEN DROPPED FOR OUR REGION AS WIDESPREAD SEVERE
THREAT NEVER REALLY MATERIALIZED AS INITIALLY ANTICIPATED DUE
PRIMARILY TO THE LACK OF INSTABILITY BUT ALSO SIGNIFICANT DRY
SLOTTING WHICH WAS NOT EXACTLY FORESEEN. ALL THIS TO SAY THAT
ALTHOUGH A SIGNIFICANT SEVERE EVENT DID NOT MATERIALIZE...A FEW
ISOLD SEVERE STORMS DID PRODUCE SOME DAMAGING WIND GUSTS OVER
EXTREME SW ARKANSAS AND ONE POSSIBLE TORNADO OVER NE TX LATE
SUNDAY.
NOW SHIFTING GEARS TO THE ACTUAL COLD FRONT AND POST-FRONTAL
CONDITIONS...THE FRONT ITSELF WAS LOCATED ALONG A PBF...TXK...CRS
LINE AS OF 10Z THIS MORNING GENERALLY SPLITTING OUR CWA IN HALF.
CONVECTION CONTINUES OUT AHEAD OF THE FRONT WITH MAINLY LIGHT TO
MODERATE SHWRS AND A FEW EMBEDDED TSTMS EXTENDING FROM S CNTRL AR
BACK OVER MUCH OF N LA AND LOWER E TX. BEHIND THE FRONT...GUSTY NW
WINDS AND SHARPLY COOLER TEMPERATURES ARE FOUND OVER SE OK AND
EXTREME NE TX. THE VERY TIGHT PRESSURE GRADIENT HAS PROMPTED A
LAKE WIND ADVISORY AREA WIDE FOR TODAY...ALBEIT STARTING A BIT
LATER ACROSS OUR SERN HALF AS CONDITIONS WILL NOT BE MET OVER
THESE AREAS UNTIL AROUND MIDDAY AND PERSISTING THROUGH MIDNIGHT.
THE NEXT DILEMMA IS DETERMINING HOW FAR TEMPERATURES WILL FALL
LATER TONIGHT INTO TUESDAY MORNING AND IF WE SEE NEAR FREEZING OR
EVEN SUB-FREEZING READINGS...HOW FAR SOUTH WILL THEY MAKE IT. THE
BEST HACK FOR NOW IS SE OK...ALL OF OUR NRN TIER AR COUNTIES AND
POSSIBLY RED RIVER COUNTY IN NE TX. HAVE GONE AHEAD AND ISSUED A
FREEZE WARNING FOR THESE AREAS TO BEGIN AFTER MIDNIGHT AND LASTING
THROUGH LATE MORNING ON TUESDAY. ALTHOUGH THE DURATION SEEMS A BIT
LONGER THAN WHAT MAY ACTUALLY OCCUR...WANTED TO MAKE SURE WE ARE
COVERED ON EITHER SIDE IN CASE THE AIR MASS IS EVEN COLDER THAN
CURRENTLY FORECAST. A FEW OTHER NOTES WORTH MENTIONING INCLUDE
WIND CHILLS IN THE 20S AND 30S OVERNIGHT INTO TUESDAY MORNING EVEN
WITH THE WINDS DECREASING SLIGHTLY AFTER MIDNIGHT. THE THREAT OF
FREEZING TEMPERATURES OVER THESE SAME AREAS WILL BE POSSIBLE
ONCE AGAIN ON WEDNESDAY MORNING AND MAYBE A FEW LOCATIONS FARTHER
SOUTH IN SRN AR/NRN LA SO WILL NEED TO MONITOR FOR ADDITIONAL FREEZE
WARNINGS.
TEMPERATURES WILL GRADUALLY MODERATE THROUGH THE REMAINDER OF THE
WEEK AND GENERALLY RUN NEAR SEASONAL AVERAGES WITH ANOTHER CHANCE
OF SHWRS AND TSTMS RETURNING LATE THURSDAY INTO FRIDAY WITH THE
ARRIVAL OF OUR NEXT COLD FRONT. THE WEEKEND LOOKS MIXED WITH A
BRIEF BREAK FROM THE RAIN EARLY SATURDAY BUT THEN RETURNING BY
LATE SATURDAY AND ESPECIALLY SUNDAY WITH AN UPPER LEVEL
DISTURBANCE SHIFTING ACROSS THE REGION FROM THE SW TX. /19/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 67 36 60 36 68 / 60 20 0 0 0
MLU 70 36 60 33 67 / 70 40 0 0 0
DEQ 55 30 60 32 66 / 30 10 0 0 0
TXK 58 34 60 36 66 / 30 10 0 0 0
ELD 65 33 60 32 66 / 60 30 0 0 0
TYR 58 34 61 36 68 / 30 10 0 0 0
GGG 62 34 61 34 68 / 30 10 0 0 0
LFK 70 36 63 34 69 / 60 20 0 0 0
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...LAKE WIND ADVISORY FROM NOON TODAY TO MIDNIGHT CDT TONIGHT FOR
THE FOLLOWING ZONES: ARZ060-061-071>073.
LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING
ZONES: ARZ050-051-059-070.
FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING
ZONES: ARZ050-051-059>061.
LA...LAKE WIND ADVISORY FROM NOON TODAY TO MIDNIGHT CDT TONIGHT FOR
THE FOLLOWING ZONES: LAZ001>006-010>014-017>022.
OK...LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING
ZONES: OKZ077.
FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING
ZONES: OKZ077.
TX...LAKE WIND ADVISORY FROM NOON TODAY TO MIDNIGHT CDT TONIGHT FOR
THE FOLLOWING ZONES: TXZ152-153-165>167.
LAKE WIND ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR THE FOLLOWING
ZONES: TXZ096-097-108>112-124>126-136>138-149>151.
FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR THE FOLLOWING
ZONES: TXZ096.
&&
$$
13
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
751 AM EDT MON APR 14 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 533 AM EDT MON APR 14 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER
THE WEST COAST AND A DOWNSTREAM TROUGH FROM HUDSON BAY THE NRN AND
CNTRL PLAINS. A POTENT WELL DEFINED SHORTWAVE TROUGH WITH COMMA
RADAR SIGNATURE WAS LIFTING NORTHEAST INTO SW WI. THE COMBINATION OF
UPPER LEVEL DIV WITH THE RIGHT ENTRANCE OF THE 140-150 KNOT 300 MB
JET OVER NRN ONTARIO...STRONG QVECTOR CONV AND 700-500 MB FGEN
SUPPORTED MODERATE TO HEAVY SNOW FROM N CNTRL WI THROUGH CNTRL UPPER
MI. RADAR INDICATED THE HIGHER REFLECTIVITY ALIGNED WITH THE MAX
FGEN FROM NEAR IMT TO SE MARQUETTE COUNTY. TWO TO THREE INCHES HAD
FALLEN IN MANY LOCATIONS OF CNTRL UPPER MI BY 09Z WITH ONE INCH TO THE
SE AT ISQ. GIVEN THE WET HEAVY NATURE OF THE SNOW...SLR VALUES WERE
LOW...GENERALLY AT OR BELOW 10/1.
TODAY...AS THE SHORTWAVE LIFTS TO THE NORTHEAST...EXPECT THE SNOW TO
GRADUALLY DIMINISH THIS MORNING AROUND 15Z. ADDITIONAL ACCUMULATIONS
OF 2 TO 3 INCHES WOULD BRING TOTALS INTO THE 3 TO 6 INCH RANGE. THE
STRONG UPSLOPE NRLY FLOW WILL ALSO HELP BOOST SNOW AMOUNTS TOWARD
THE HIGHER END OF THE RANGE OVER THE HIGHER TERRAIN OF N CNTRL UPPER
MI. ALTHOUGH WINDS GUSTING TO 35 MPH WILL ALSO PRODUCE BLOWING
SNOW...THE SNOW WAS WET ENOUGH SO THAT VSBYS WERE MAINLY ABOVE
1/2SM. SOME LOCALIZED LOWER VSBY WOULD BE EXPECTED NEAR THE LAKE
SUPERIOR SHORELINE. AS THE STRONGER DYNAMICS LIFT OUT BY THIS
AFTERNOON SOME LIGHT SNOW WILL CONTINUE INTO THE NORTH AS 850 MB
TEMPS DROPPING TO AROUND -16C AND SOME LIMITED OPEN WATER PROVIDES
ENOUGH HEAT/MOISTURE FOR ADDITIONAL LAKE EFFECT AND OROGRAPHIC SNOW
FOR HIGHER TERRAIN LOCATIONS.
TONIGHT...ANY LINGERING LAKE EFFECT SNOW WILL DIMINISH BUT COULD
STILL PRODUCE A DUSTING OVER THE NORTH. MUCH COLDER AIR WILL MOVE IN
WITH MIN READINGS INTO THE 5F TO 15F RANGE.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 417 AM EDT MON APR 14 2014
LONGWAVE TROUGH AXIS ACROSS THE GREAT LAKES ON TUESDAY. QUITE CHILLY
WITHIN THE TROUGH WITH H85 TEMPS DOWN TO -20C OVER LK SUPERIOR.
SHORTWAVE DROPPING SE IN THE MEAN TROUGH INCREASES DEPTH OF QUALITY
OF MOISTURE AND ALSO STEEPENS H9-H7 LAPSE RATES ON TUESDAY. LAKE
EFFECT FLURRIES MAY TRANSITION TO DIURNALLY DRIVEN SNOW SHOWERS WITH
COVERAGE EXTENDING INLAND TOWARD WI BORDER AND LK MICHIGAN SHORE.
POPS LOW CHANCE AT BEST THOUGH. TEMPS WILL BE VERY COOL FOR THIS
TIME OF YEAR WITH READINGS IN THE LOW-MID 20S NORTH AND AROUND 30
IN THE SOUTHERN CWA. NORMAL HIGHS ARE INTO THE LOWER 50S OVER THE
SOUTH. WAVE MOVES EAST ON TUESDAY EVENING WHICH SHOULD ALLOW SKIES
TO TEMPORARILY CLEAR OUT AHEAD OF NEXT SYSTEM THAT BEGINS TO IMPACT
FAR WEST CWA WITH LGT SNOW LATE TUESDAY NIGHT. MIN TEMPS MAY DIP
INTO SINGLE DIGITS FOR MANY AREAS BEFORE THICKER CLOUDS MOVE BACK
IN LATER DURING THE NIGHT.
WHAT TO DO WITH SYSTEM FOR WEDNESDAY WILL BECOME LARGER FOCUS ONCE
WE GET PAST SYSTEM BRINGING SNOW TO MUCH OF UPR MICHIGAN TODAY. WILL
TWO CAMPS STILL PRESENT IN THE MODELS. NAM/GFS BRING SHORTWAVE AND SFC
LOW PRESSURE AND INVERTED TROUGH ACROSS UPPER MISSISSIPPI RIVER
VALLEY QUICKER...AND HAVE MORE QPF. BOTH CAMPS OF MODELS GENERATE QPF
INTO WESTERN CWA BY 12Z WEDNESDAY...SUPPORTED BY LARGER SCALE
DIFFLUENCE ALOFT BTWN JETS EMERGING FM THE PLAINS AND CROSSING LK
SUPERIOR REGION. ECMWF AND GEM-NH AND UKMET ARE SLOWER AND NOT AS
HEAVY WITH QPF OVER UPR MICHIGAN...KEEPING FOCUS FOR HEAVIER PRECIP
OVER CNTRL MN INTO WCNTRL WI ALONG TRACK OF SFC LOW PRESSURE WAVE
THROUGH MUCH OF WEDNESDAY BEFORE LIFTING IT ACROSS MAINLY WESTERN
HALF OF UPR MICHIGAN LATER WEDNESDAY INTO WEDNESDAY NIGHT. DESPITE
MODEL DIFFERENCES...ENOUGH EVIDENCE TO PUSH POPS TO LIKELY WEDNESDAY
AND WEDNESDAY NIGHT. ALSO THERE IS DECENT AGREEMENT THAT WESTERN AND
PROBABLY CENTRAL CWA WILL SEE MODERATE SNOW AMOUNTS FROM THIS
SYSTEM...WITH BULK OF SNOW FALLING WEDNESDAY AFTN THROUGH EARLY
THURSDAY MORNING. MIXING RATIOS 2.5-3G/KG WOULD SUPPORT MODERATE SNOW
AMOUNTS OF 3 TO 6 INCHES OVER 12 HOUR PERIOD. MODELS SHOWING AREA OF
MID-LEVEL FGEN...FAIRLY STRONG CONSIDERING HOW FAR OUT WE ARE
STILL...THAT COULD RESULT IN BANDS OF HEAVIER SNOW OVER LIKELY THE
WEST CWA. HPC HEAVY SNOW GRAPHICS SHOW MUCH OF FAVORED AREA WITH
MODERATE PROBABILITY OF SEEING 4 INCHES OF SNOW WITH LOW PROBABILITY
OF SEEING 8 INCHES. BASED ON 1000-850MB AND 850-700MB THICKNESSES AND
H85 TEMPS...SNOW WILL MIX WITH AND COULD CHANGE TO RAIN LATER
WEDNESDAY NIGHT OVER SCNTRL AND EAST CWA. RAIN/SNOW MIX CONTINUES
INTO THURSDAY FOR THOSE AREAS WHILE WIDESPREAD SNOW DIMINISHES
ELSEWHERE. NO WATCH ATTM...AS IT WOULD BE LATER 5TH PERIOD AND STILL
NEED TO GET THROUGH THIS ONGOING SNOW SYSTEM TO AVOID ANY CONFUSION.
WILL CONTINUE TO MENTION IN EHWO/HWOMQT.
LATER THURSDAY AND ON INTO NEXT WEEKEND THE FORECAST IS AT BEST
MUDDLED...WHICH LEADS TO LOWER THAN AVERAGE CONFIDENCE FOR SURE. GFS
MORE OR LESS IS FAIRLY CONSISTENT IN SHOWING SHORTWAVE IN SOUTHERN
STREAM LIFTING ACROSS UPPER GREAT LAKES WHILE PHASING WITH NORTHERN
BRANCH SHORTWAVE TROUGH. RESULT IS WRAPPED UP SFC LOW WITH
WIDESPREAD RAIN AND SNOW OVER UPR MICHIGAN. GEM-NH SUPPORTS IDEA
SOMEWHAT THOUGH IT IS SLOWER AND NOT AS STRONG. ECMWF WAS TRENDING
NORTH AND WEST WITH THAT SYSTEM...BUT WITH LATEST RUN NOW HAS WENT
BACK TO THE SOUTHEAST...KEEPING MUCH OF UPR MICHIGAN DRY ON FRIDAY.
ECMWF IS NOT PHASING THE SOUTHERN WAVE NEAR AS MUCH AS GFS ATTEMPTS
TO SHOW. CONSENSUS POPS...CAPPED AT LOW CHANCE...WILL BE UTILIZED
FOR NOW. WHATEVER LOW PRESSURE SYSTEM WOULD BE EXITING TO START THE
WEEKEND...WITH HIGH PRESSURE AND DRIER WEATHER FOR THE REST OF THE
WEEKEND AS SHOWN BY GFS. NOT SO INDICATES THE ECMWF...WITH A QUICK
PUSH OF NEXT SHORTWAVE ENERGY AND SFC TROUGH/RAIN SHOWERS FOR
SUNDAY. LATEST RUN BACKED OFF SOME...BUT JUST SHOWS THE HIGH
VARIABILITY THAT CURRENTLY EXISTS FOR THAT FORECAST TIME FRAME. ONE
PRETTY SURE THING IS IT LOOKS LIKE WARMING TREND /TEMPS TRYING TO
RETURN TOWARD AVERAGE/ DEVELOPS NEXT WEEKEND AFTER WHAT APPEARS TO
BE A CHILLY MID APRIL WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 750 AM EDT MON APR 14 2014
SAW...A LOW PRES MOVING THROUGH NRN LOWER MI THIS MORNING WILL KEEP
MODERATE SNOW GOING AT SAW THROUGH MID MORNING. STRONG NRLY UPSLOPE
WINDS TO 30 KNOTS WILL ALSO CONTINUE PRODUCING BLOWING DRIFTING SNOW.
LIFR CONDITIONS WILL GRADUALLY IMRPROVE TO MVFR BY MIDDAY AS THE
ARRIVAL OF DRIER AIR...DAYTIME HEATING AND SLOWLY WEAKENING PRES
GRADIENT/WINDS ARRIVE. MVFR CONDITIONS WILL PREDOMINATE THROUGH THE
REST OF THE FCST PERIOD.
IWD/CMX...SNOW ASSOCIATED WITH THE LOW PRES SYSTEM WILL REMAIN TO
THE EAST. BUT WITH A FAVORABLE UPSLOPE N WIND AT IWD...MVFR
CIGS SHOULD PREDOMINATE AT THAT LOCATION. BEST CHC FOR SOME
IMPROVEMENT TO VFR WILL BE THIS AFTERNOON...WHEN DAYTIME HEATING
MIGHT LIFT THE CLOUD BASE INTO THE VFR RANGE. BY LATE THIS
EVENING...VFR CONDITIONS WILL BE MORE LIKELY AS HIGH PRES BUILDS IN
FROM THE WEST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 417 AM EDT MON APR 14 2014
NORTH GALES 35-40 KNOTS FOR TODAY...MAINLY EAST HALF...AS LOW
PRESSURE SYSTEM TRACKS ACROSS LOWER MICHIGAN THIS MORNING AND
EVENTUALLY ACROSS QUEBEC BY THIS EVENING. WINDS QUICKLY DIMINISH
BY THIS EVENING AND SHOULD REMAIN BLO 20 KTS OVER MOST OF THE LAKE
THROUGH TUESDAY. LOW PRESSURE SYSTEM LIFTING ACROSS UPPER GREAT
LAKES LATER ON WEDNESDAY WILL RESULT IN EAST TO NORTHEAST WINDS UP
TO 25 KTS OVER MAINLY WESTERN LAKE INTO THURSDAY. WINDS DIMINISH TO
LESS THAN 20 KTS REST OF THE FORECAST PERIOD.
&&
.HYDROLOGY...
ISSUED AT 417 AM EDT MON APR 14 2014
REPORTS OF ICE JAMS IN DELTA COUNTY SUNDAY ON ESCANABA RIVER AND
ASSOCIATED TRIBUTARIES. HYDROLOGIC STATEMENT WAS ISSUED SUNDAY
EVENING AND THIS IS VALID THROUGH THIS EVENING. PRECIPITATION OCCURS
MAINLY IN THE FORM OF SNOW TODAY. OPPORTUNITIES FOR WIDESPREAD
PRECIPITATION ALSO IN THE FORECAST FOR WEDNESDAY THROUGH THURSDAY...
AND POSSIBLY FRIDAY. FEASIBLE THAT TOTAL PRECIPITATION FOR THIS WEEK
MAY EXCEED AN INCH IN SOME AREAS OF UPPER MICHIGAN. THIS PRECIP
ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES
OVER MAINLY WESTERN UPPER MICHIGAN WILL RESULT IN ANOTHER PERIOD
OF SNOWMELT AND RUNOFF ONCE WARMER TEMPERATURES MOVE BACK INTO THE
REGION BY NEXT WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 7 AM CDT THIS MORNING FOR MIZ010-
011.
WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ007-
013-014-085.
WINTER WEATHER ADVISORY UNTIL 10 AM CDT THIS MORNING FOR MIZ012.
WINTER STORM WARNING UNTIL 11 AM EDT THIS MORNING FOR MIZ005-006.
LAKE SUPERIOR...
GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR LSZ249>251-266-
267.
GALE WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR LSZ244-245-264-
265.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...JLB
MARINE...JLA
HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
630 AM CDT MON APR 14 2014
.UPDATE...
ISSUED AT 630 AM CDT MON APR 14 2014
THERE IS A WEAK DISTURBANCE IN THE NORTHWEST FLOW CURRENTLY MOVING
DOWN ACROSS THE DAKOTAS. THIS FEATURE SHOULD BRING AT LEAST A
CHANCE FOR SOME LIGHT PCPN...PROBABLY SPRINKLES OR FLURRIES...THIS
AFTERNOON TO PARTS OF EASTERN NEBRASKA. RECENT RUNS OF THE RAP AND
HRRR MODELS SHOW THAT TREND...AND THESE MAY EVEN LINGER INTO EARLY
EVENING. LOOK FOR HIGHS MAINLY FROM AROUND 40 UP TO THE LOWER AND
POSSIBLY MID 40S.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 306 AM CDT MON APR 14 2014
STLT IMAGERY THIS MORNING WAS SHOWING A ANOMALOUS LONGWAVE TROF
SITUATED OVER THE CNTRL U.S. WITH POTENT VORT MAX JUST EAST OF THE 4
CORNERS REGION. UPSTREAM THEN...HIGHLY AMPLIFIED RIDGE WAS SITUATED
OVER THE WRN CONUS/WRN CANADA. AT THE SFC...DEEP LOW PRESSURE WAS
CENTERED OVER NRN IL WITH LEADING EDGE OF ATTENDANT COLD FRONT
PUSHING DEEP INTO THE SRN PLAINS STATES. OTHERWISE AREA OF -SN HAS
FINALLY PUSHED OUT OF ERN NEB AND INTO SWRN IA. EXPECT ACTIVITY TO
TAPER OFF THOUGH BY MID MORNING.
MODELS ARE IN GOOD AGREEMENT MEAN TROF WILL PREVAIL OVER THE CONUS
THRU THE NEAR TERM PDS WITH NEXT SHOT FOR PCPN COMING WED/WED NIGHT
WHEN NEXT PAC NW SHORTWAVE MOVES ACROSS THE NRN/CNTRL PLAINS. UNTIL
THEN...TEMPS ARE THE MAIN ISSUE TO CONTEND WITH. DEEP TROF ALOFT AND
ASSOCIATED COLD AIR ADVECTION HAS RESULTED IN AN IMPRESSIVE TEMP
SWING OVER THE REGIONS OVER THE LAST 24HRS...AND AT THIS POINT COLD
AIRMASS EXPECTED TO HANG IN TIGHT AT LEAST THRU TONIGHT. COLD THEN
TODAY WITH TEMPS STRUGGLING TO REACH THE LOWER 40S. FURTHERMORE...
GUSTY NW WINDS/COLD WIND CHILL INDICES WILL ENSURE LOUSY CONDITIONS
THRU THE DAY. AS FOR HIGHS TUE/WED...MODERATE REBOUND ADVERTISED
BUT STILL JUST BELOW NORM.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 306 AM CDT MON APR 14 2014
WED AFTN/NIGHT NEXT ROUND OF PCPN WILL BE POSSIBLE IN ASSOCIATION
WITH NEXT COLD FRONT SWEEPING INTO THE CNTRL PLAINS. MODELS IN GOOD
AGREEMENT ADVERTISING DEEP LYR QG FORCING WILL BE IN PLACE AT TIME
OF FROPA. PCPN TYPE INITIALLY RA...THEN POSSIBLE RA/SN MIX WED
NIGHT/THUR MORNING WHEN BRUNT OF CAA ARRIVES. FOCUS FOR PCPN WILL
GRADUALLY SHIFT EAST THRU FRIDAY AS BEST DYNAMIC FORCING EXITS THE
REGION. SAT NIGHT/SUN...ECM IS MORE AGGRESSIVE WITH QPF OVER SRN
NEB/ERN KS IN RELATION TO 295K UPGLIDE/LOW COND PRES DEF. GOING
FCST ALREADY HAS THIS COVERED WITH SMALL POPS IN PLACE. OTHERWISE...
WARMING TREND ON TAP THRU THE EXTENDED PD WITH LOW 70S ARRIVING
EARLY NEXT WEEK.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 630 AM CDT MON APR 14 2014
LOOK FOR VFR CONDITIONS TO PREVAIL THROUGH THE PERIOD. EXPECT VRBL
MID AND HIGH LEVEL CLOUDINESS THIS MORNING...BUT INCREASING CLOUDS
IN THE 4000 TO 8000 FOOT LAYER THIS AFTERNOON WITH THE DISTURBANCE
MOVING IN FROM THE NORTHWEST. COULD SEE SOME LIGHT SNOW OR LIGHT
RAIN (PROBABLY MOSTLY FLURRIES OR SPRINKLES) THIS AFTERNOON MAINLY
AT KOFK AND KLNK. THOSE CLOUDS SHOULD THEN DISIPATE THIS EVENING.
WINDS WILL ALSO DECREASE THROUGH THE DAY...BECOMING LIGHT TONIGHT.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...MILLER
SHORT TERM...DEE
LONG TERM...DEE
AVIATION...MILLER
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
623 AM CDT MON APR 14 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT MON APR 14 2014
A WEAK UPPER LEVEL DISTURBANCE...CURRENTLY ACROSS ERN MT/WRN ND...
WILL DROP SOUTH THROUGH THE FCST AREA TODAY. LAPSE RATES FROM
850-700MB ARE STEEP AND MOIST BUT THE 850MB-SFC LAYER IS VERY DRY
WITH DEW POINTS IN THE TEENS AND LOWER 20S. WHILE TEMPERATURE RISE
IN THE LOW TO MID 40S THIS AFTN...WET BULB ZERO HEIGHTS WITH BE
CLOSE TO THE GROUND AND THE HRRR AND RAP SHOW SNOW FOR THE PTYPE. SO
ISOLATED SNOW SHOWERS ARE IN THE FORECAST.
NO MEASURABLE QPF WAS INDICATED IN THE RAP SOLN BUT THE HRRR
ACTUALLY SHOWS SCATTERED SNOW SHOWERS WITH SEVERAL STREAKS OF 0.01
QPF AND THE MODEL CONSENSUS INDICATES H700MB AROUND -18C AT KVTN
WHICH IS VERY IMPRESSIVE FOR MID APRIL.
THIS DISTURBANCE WILL DRAW ANOTHER WEAK PIECE OF ARCTIC HIGH
PRESSURE INTO THE ERN HALF OF THE FORECAST AREA TONIGHT WHILE THE
WRN HALF DEVELOPS SOUTH WINDS AS LOW PRESSURE FORMS ACROSS THE NRN
HIGH PLAINS. LOWS TONIGHT SHOULD FALL INTO THE LOW TO MID 20S WITH
GENERALLY CLEAR SKIES.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 345 AM CDT MON APR 14 2014
WARM AIR QUICKLY SPREADS NORTHEAST INTO THE REGION TUESDAY...WITH
H85 TEMPS RISING TO 8C TO 12C BY AFTERNOON. THIS SHOULD YIELD HIGHS
IN THE UPPER 50S TO MID 60S. HAVE RAISED LOWS TUESDAY NIGHT...AS
SOUTHERLY LOW LEVEL JET KEEPS ATMOSPHERE MIXED AND H85 TEMPS
CONTINUE TO WARM...NEARING 13C.
SHORTWAVE ENERGY DIVES SOUTHEAST INTO THE PLAINS LATE WEDNESDAY
THROUGH THURSDAY. MODELS CONTINUE TO MOVE THIS THROUGH QUICKLY AS AN
OPEN WAVE...WITH THE BEST UPPER LEVEL DYNAMICS CROSSING THROUGH
NORTHERN KANSAS. WILL CONTINUE THE HIGHEST POPS /NEAR 40 PERCENT/
ACROSS FAR SOUTHERN NEBRASKA. SOUNDING PROFILES INDICATE A MIX OF
RAIN AND SNOW OR WET SNOW...BUT NOT EXPECTING MUCH QPF AT THIS
POINT. CHILLY WEATHER IN THE WAKE OF THE SYSTEM THURSDAY...AS MORE
ARCTIC AIR MOVES SOUTH INTO THE PLAINS.
AS WE HEAD INTO NEXT WEEKEND...THE GFS AND ECMWF ARE BOTH
ADVERTISING UPPER LEVEL ENERGY ADVANCING EASTWARD FROM THE PACIFIC
INTO THE SOUTHWEST CONUS. THIS AIDS IN THE DEVELOPMENT OF A SURFACE
TROUGH ALONG THE HIGH PLAINS...WITH SOUTHERLY FLOW EAST OF THE
TROUGH DRAWING GULF MOISTURE NORTHWARD INTO THE PLAINS. IT WOULD
APPEAR THAT SOME TSTM ACTIVITY IS POSSIBLE SATURDAY NIGHT ON THE
NOSE OF A SOUTHERLY LOW LEVEL JET...AND THEN PERHAPS SUNDAY AS A
COLD FRONT AND LOW PRESSURE SYSTEM ADVANCE EAST ACROSS THE AREA.
ALTHOUGH BOTH MODELS DRAW MOISTURE NORTH INTO THE PLAINS...THERE ARE
DIFFERENCES IN THE HANDLING OF THE UPPER LEVEL ENERGY ACROSS THE
SOUTHWEST CONUS. WILL LEAVE THE FORECAST DRY AT THIS TIME...AS THE
MODELS SEEM TO BE JUST STARTING TO LATCH ONTO THIS SCENARIO. IF THIS
CONTINUES TO BE SHOWN IN FUTURE MODEL RUNS...THEN SOME THUNDER
MENTION WILL HAVE TO BE ADDED TO THE WEEKEND FORECAST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 620 AM CDT MON APR 14 2014
VFR IS GENERALLY EXPECTED TODAY AND TONIGHT.
THE DISTURBANCE ACROSS SD/ND THIS AM MOVES THROUGH NCNTL NEB THIS
AFTN SPARKING ISOLATED TO PERHAPS SCATTERED SHSN/MVFR CONDITIONS.
THIS SHOULD DISSIPATE BY 00Z WITH VFR ALL AREAS THEREAFTER.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
835 AM EDT MON APR 14 2014
.SYNOPSIS...
THE WEATHER WILL BE MILD AND DRY THROUGH MOST OF TODAY.
MEANWHILE LOW PRESSURE OVER THE CENTRAL U.S. WILL MOVE NORTHEAST
AND BRING SHOWERS TO THE AREA LATE THIS AFTERNOON INTO TONIGHT.
ON TUESDAY, A STRONG COLD FRONT WILL PASS THROUGH. LOCALLY HEAVY
RAIN WILL BE POSSIBLE AHEAD OF THE COLD FRONT WITH THE POTENTIAL
FOR ACCUMULATING SNOWS BEHIND IT ACROSS CENTRAL NEW YORK. HIGH
PRESSURE WILL BRING A RETURN TO FAIR WEATHER ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
830 AM UPDATE...
FCST IN GOOD SHAPE. A FEW MDLS DVLP SCT CONVECTION THIS AFTN
ALONG A WEAK PRE-FNTL SFC TROF BUT INSPECTION OF PROFILES SUGGESTS
--SHRA OUT OF A MID DECK WITH ONLY A FEW HUNDRED JOULES OF MID LVL
INSTABILITY. TEMPS WILL BE TRICKY THIS AFTN. 925 TEMPS WILL BE A FEW
DEG COOLER AND WE`LL HAVE MORE IN THE WAY OF CLD CVR BUT WE`RE
STARTING OUT VERY MILD...SO NO CHGS THERE. PREV BLO...
630 AM UPDATE... 993MB SFC LOW HAS NOW MVD INTO NRN LOWER
MICHIGAN WITH STRONG COLD FRONT DRAPED BACK THRU THE MIDWEST. AS
IT CROSSED CHICAGO, O-HARE DROPPED 16 DEGREES IN ONE HOUR. THIS
SYSTEM WILL EVENTUALLY CROSS OUR AREA TOMORROW. IN THE MEANTIME
HAVE HAD TO DO SOME FINAGLING WITH TEMPS FOR TDA AS MOST OF CWA
WERE WITHIN 4-5 DEGREES OF HIGH TEMPS TDA. WENT SIGNIFICANTLY ABV
GUIDANCE FOR THIS UPDATE AS MOST LOCALES SHUD EASILY PUSH INTO THE
U70S. LATEST HRRR NOW HAS WIDESPREAD RAIN INTO WRN ZONES BY 22Z
AND THIS WL NEED TO BE MONITORED THROUGHOUT THE DAY.
PREV DISCO BLO...
155 AM UPDATE...
SPRINGTIME STORM SYSTEM THAT BROUGHT SVR WX TO THE PLAINS YDA WL BE
HEADED NORTHEAST OVR THE NEXT SEVERAL DAYS. WM FNT DRAPED ACRS SRN
ONTARIO AND NRN NY STATE EXTENDS FM SFC LOW LOCATED OVR THE QUAD
CITIES REGION. ASSOC H5 TROF IS SPINNING THRU THE CNTRL PLAINS WITH
WIDESPREAD AREA OF SHOWERS/TSTMS ALONG MS RVR.
ALL THIS MEANS WITH REGARD TO OUR WX IS A MILD SRLY FLOW CONTG TDA.
GOM IS CURRENTLY WIDE OPEN AND DRAWING IN WARM/MOIST AIR TO CNTRL
PART OF NATION WITH PW VALUES WELL ABV 1 INCH. AS TROF SLIDES EVER
CLOSER TO CWA THRU THE AFTN EXPECT MOISTURE TO INCRS TO OVR 1.00
INCHES. THIS HELPS TO INCRS DWPT VALUES INTO THE 50S AND PRECLUDE
FIRE WX CONCERNS FOR TDA AS OPPOSED TO YDA.
IN ADDITION AN INCRS IN CLDS FM THE APPCHG SYSTEM WL SPREAD MOCLDY
SKIES TO WRN ZONES DRG THE AFTN HRS WITH A HIGH THIN CIRRUS EXPECTED
RMNDR OF AREA. THIS WL HELP TO TEMPER TEMP RISE TDA WITH MOST HIGHS
IN THE M70S.
WARM ADVECTION WL COMBINE WITH APPCHG UL FRCG AND LGT SHOWERS WL
START TO DVLP ACRS THE WEST BTWN 18Z AND 21Z THIS AFTN BFR SLIDING
EAST, PERHAPS GETTING AS FAR EAST AS THE I-81 CORRIDOR IN CNY BY 00Z
TONIGHT. MODELS AGREE WITH PLACEMENT OF CDFNT AT 00Z TONIGHT BUT
DIFFER WITH REGARD TO QPF WITH GFS MUCH MORE BULLISH THAN EURO AND
NAM. WUD CERTAINLY NOT BE SURPRISED TO SEE A SPRINKLE IN CNTRL SXNS
OF CWA UNDER STRONG WARM ADVECTION BUT FEEL THE CRUX OF THE PCPN WL
BE FELT IN THE FINGER LKS REGION THIS AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
4 AM UPDATE...
POPS INCRS TONIGHT FM WEST TO EAST AS FRCG FM FRONT MVS CLOSER TO
CWA. LKLY POPS EXPECTED BY 06Z, THEN INCRSG TO 100 POPS BY MRNG.
GIVEN STRONG MOISTURE SURGE (THETA-E RIDGE) AND WARM AIR ADVECTION
HV GONE WITH MORE SHOWERY MENTION THRU 09Z TONIGHT. H5 LOW WL BE
SITTING UP ACRS HUDSON BAY WITH L/WV TROF BCMG NEGATIVELY TILTED TUE
MRNG. 250MB SPEED MAX WL STRENGTHEN TO +120KTS BY DAYBREAK WITH CWA
IN RIGHT-ENTRANCE REGION ARND 09Z, THUS WL GO WITH MORE OF A RAIN
SCENARIO AFT THIS TIME.
HV ADDED IN CHC FOR THUNDER DRG THE OVRNGT AS SI`S APPRCH ZERO,
MLCAPES ARND 100 J/KG AND K-INDICES > 30. 00Z MODELS AGREE THAT
CDFNT WL BE ENTERING INTO WRN ZONES BY 12Z TUESDAY.
TEMPS WL FALL THRU THE DAY TUE IN CNY AS CDFNT COMES BLASTING THRU.
MAY SEE A BRIEF RISE IN TEMPS ACRS SERN ZONES DRG THE MRNG BFR
HOLDING STEADY THEN FALLING STEADILY AFT 18Z. HV SIDED MORE WITH THE
TIMING OF THE CHANGEOVER FM RAIN TO SNOW/SLEET WITH THE GFS AND EURO
AS NAM SEEMS TO BE TOO SLOW. EXPECT ALL RAIN DRG THE MRNG HRS AND
THEN SLOWLY MIXING WITH SLEET BY EARLY AFTN ACRS THE FINGER LKS,
THEN BCMG ALL SNOW AFT 21Z IN THE FINGER LKS. PCPN WL START TO MIX
WITH SLEET AND SNOW AFT 21Z ACRS THE I-81 CORRIDOR IN NY STATE WITH
RAIN EXPECTED THRU 00Z WED IN PIKE AND SULLIVAN CNTYS.
EXPECT ALL SNOW SHOWERS TUE NGT WITH POSSIBLE EXCEPTION OF FAR SERN
ZONES EARLY AS THEY TRANSITION OVR. SNOWFALL AMNTS FM TIME OF
TRANSITION (LATE AFTN TUE) UNTIL PCPN EXITS STAGE RIGHT ARND 06Z WED
LOOKS TO BE ON THE ORDER OF 1-1.5 INCHES.
WITH H8 TEMPS PROGGED TO DROP TO NR -14C WED MRNG, EXPECT OVRNGT
LOWS TO DIP INTO THE TEENS. THIS IS UNDER STRONG NW WINDS AS WELL.
IF WINDS CAN DECOUPLE, TEMPS MAY DROP EVEN LOWER. THIS WUD PUT
RECORD LOWS IN JEOPARDY FOR THIS DATE. KBGM`S RECORD LOW IS 24F,
KAVP IS 20F AND KSYR IS 23F.
UNDER FULL SUN WITH HIPRES BUILDING IN ON WED, MAX TEMPS WL QUICKLY
CLIMB INTO THE 40S. HIGH WL SHIFT OFF TO THE EAST WED NGT, ALLOWING
RETURN FLOW TO RE-ESTABLISH ITSELF.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
315 AM UPDATE...
NO MAJOR CHANGES MADE THIS MORNING AS A FAIR AMOUNT OF MODEL
DISAGREEMENT STILL EXISTS WITH NEXT WEEKEND/S STORM SYSTEM. BEFORE
THIS HOWEVER...DRY BUT COOLER WEATHER WILL PREVAIL THROUGH THE
REMAINDER OF THE WORK WEEK AS STRONG HIGH PRESSURE REMAINS
ENTRENCHED OVER THE NORTHEAST AND EASTERN CANADA. IN TERMS OF NEXT
WEEKEND/S STORM SYSTEM...THE GFS TAKES A SFC LOW DIRECTLY OVER OUR
FCST REGION...WHILE THE ECMWF SHOWS A SFC LOW APPROACHING FROM THE
SOUTHWEST WITH THIS FEATURE GRADUALLY LOOSING STEAM AS ENERGY
TRANSFERS TO A DEVELOPING COASTAL LOW OFF THE EASTERN SEABOARD.
UNDER THE LATTER SCENARIO...MUCH OF OUR FCST REGION IS SPARED OF
APPRECIABLE RAINFALL. FOR WHAT ITS WORTH...THE CANADIAN-CMC TOO
SHOWS TRANSFERRING ENERGY ALBEIT A LITTLE FURTHER NORTH THAN THE
ECMWF. IF THIS WERE TO PANE OUT AS ADVERTISED...SOME SOME PRECIP
WOULD LIKELY WORK NORTH INTO OUR AREA. AS RESULT OF THIS THIRD
SOLUTION...WILL MAINTAIN CHC POPS ACROSS THE SOUTHERN 2/3RDS OF
THE FCST REGION FRIDAY NIGHT AND SATURDAY.
PREVIOUS LONG TERM DISCUSSION...
MEDIUM RANGE MODELS START OUT IN GOOD AGREEMENT EARLY IN THE
EXTENDED PERIOD THEN DIVERGE BY NEXT WEEKEND. INITIALLY SFC HIGH
PRES OVER NRN NEW ENGLAND AND NOVA SCOTIA WILL BRING FAIR AND COOL
WEATHER TO THE AREA WITH LOWS WED NIGHT IN THE MID TO UPPER 20S
FOLLOWED BY UPPER 20S TO MID 30S ON THURSDAY NIGHT. MAXES BOTH
THURSDAY AND FRIDAY WILL RANGE IN THE 50S WITH SOME MODIFICATION
ON FRIDAY.
FRIDAY NIGHT THROUGH SUNDAY THE OPERATIONAL GFS TAKES A SFC LOW
IN THE TN VALLEY AND TRACKS IT NORTHEAST ACROSS OUR VCNTY THEN INTO
EASTERN CANADA BY SUNDAY. A WET SCENARIO FOLLOWED BY WRAP AROUND
MOISTURE SATURDAY NIGHT INTO SUNDAY. THE ECMWF PLACES THIS FEATURE
FARTHER SOUTH AND WEAKER THEN MOVES IT OFF THE MID ATLANTIC COAST
KEEPING THE REGION BASICALLY DRY. FOLLOWED HPC GUIDANCE WHICH
KEEPS THE SYSTEM TO OUR SOUTH BUT WILL INCLUDE CHC POPS FROM
FRIDAY NIGHT THROUGH SATURDAY NIGHT FOR RAIN SHOWERS.
&&
.AVIATION /13Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS OUT OF THE GATE THIS MORNING. MAIN STORY THROUGH
THE DAY WILL BE STRONG SOUTHWEST WINDS WITH GUSTS IN EXCESS OF 25
KTS POSSIBLE AT ALL SITES. FCST MODELS SHOW SOME SHWR ACTIVITY
DEVELOPING BY MID/LATE AFTERNOON...HOWEVER OVERALL CONFIDENCE IS
TO LOW AT THIS POINT TO INCLUDE IN THE FCST. MUCH BETTER CHANCES
FOR PRECIP WILL ARRIVE SHORTLY AFTER 00Z AS PRECIP SHIELD
ASSOCIATED WITH COLD FRONT APPROACHES. AS THIS OCCURS...EXPECT
CATEGORICAL DECREASES TO MVFR AND POTENTIALLY IFR CONDITIONS AS
STEADY PRECIP MOVES IN. MOST LIKELY CANDIDATES FOR IFR DURING
THE OVERNIGHT PERIOD WILL BE ITH AND BGM...WITH MVFR EXPECTED
ELSEWHERE.
OUTLOOK...
TUE...RESTRICTIONS IN SCATTERED RAIN SHOWERS AND ISOLATED THUNDER
TUESDAY MORNING...WITH RAIN CHANGING TO SNOW TUE AFTERNOON/EVENING.
TUE NGT...RESTRICTIONS POSSIBLE IN SCATTERED SNOW SHOWERS.
WED-THU-FRI...VFR.
&&
.FIRE WEATHER...
4 AM MONDAY UPDATE...
DEWPOINT TEMPERATURES WILL REMAIN FAIRLY STEADY THROUGH THE DAY
BUT TEMPERATURES ARE NOT EXPECTED TO CLIMB AS HIGH AS YESTERDAY,
LEADING TO MINIMUM RELATIVE HUMIDITY VALUES REMAINING ABOVE 40%
THROUGH THE DAY. SOUTH-SOUTHWEST WINDS WILL BE STRONG AND GUSTY
AGAIN TODAY BUT ANY FIRE WEATHER CONCERNS WILL BE PRECLUDED BY
INCREASING MOISTURE AHEAD OF AN APPROACHING COLD FRONT. WIDESPREAD
RAIN WILL MOVE IN LATE TONIGHT. COLD AIR WILL MOVE IN BEHIND THE
FRONT ON TUESDAY AFTERNOON, SWITCHING RAIN OVER TO SNOW SHOWERS
BRIEFLY ON TUESDAY NIGHT, MAINLY ACROSS CENTRAL NEW YORK.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN
NEAR TERM...PVN
SHORT TERM...PVN
LONG TERM...CMG/RRM
AVIATION...CMG
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
652 AM EDT MON APR 14 2014
.SYNOPSIS...
THE WEATHER WILL BE MILD AND DRY THROUGH MOST OF TODAY.
MEANWHILE LOW PRESSURE OVER THE CENTRAL U.S. WILL MOVE NORTHEAST
AND BRING SHOWERS TO THE AREA LATE THIS AFTERNOON INTO TONIGHT.
ON TUESDAY, A STRONG COLD FRONT WILL PASS THROUGH. LOCALLY HEAVY
RAIN WILL BE POSSIBLE AHEAD OF THE COLD FRONT WITH THE POTENTIAL
FOR ACCUMULATING SNOWS BEHIND IT ACROSS CENTRAL NEW YORK. HIGH
PRESSURE WILL BRING A RETURN TO FAIR WEATHER ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
630 AM UPDATE...
993MB SFC LOW HAS NOW MVD INTO NRN LOWER MICHIGAN WITH STRONG COLD
FRONT DRAPED BACK THRU THE MIDWEST. AS IT CROSSED CHICAGO, O-HARE
DROPPED 16 DEGREES IN ONE HOUR. THIS SYSTEM WILL EVENTUALLY CROSS
OUR AREA TOMORROW. IN THE MEANTIME HAVE HAD TO DO SOME FINAGLING
WITH TEMPS FOR TDA AS MOST OF CWA WERE WITHIN 4-5 DEGREES OF HIGH
TEMPS TDA. WENT SIGNIFICANTLY ABV GUIDANCE FOR THIS UPDATE AS MOST
LOCALES SHUD EASILY PUSH INTO THE U70S. LATEST HRRR NOW HAS
WIDESPREAD RAIN INTO WRN ZONES BY 22Z AND THIS WL NEED TO BE
MONITORED THROUGHOUT THE DAY.
PREV DISCO BLO...
155 AM UPDATE...
SPRINGTIME STORM SYSTEM THAT BROUGHT SVR WX TO THE PLAINS YDA WL BE
HEADED NORTHEAST OVR THE NEXT SEVERAL DAYS. WM FNT DRAPED ACRS SRN
ONTARIO AND NRN NY STATE EXTENDS FM SFC LOW LOCATED OVR THE QUAD
CITIES REGION. ASSOC H5 TROF IS SPINNING THRU THE CNTRL PLAINS WITH
WIDESPREAD AREA OF SHOWERS/TSTMS ALONG MS RVR.
ALL THIS MEANS WITH REGARD TO OUR WX IS A MILD SRLY FLOW CONTG TDA.
GOM IS CURRENTLY WIDE OPEN AND DRAWING IN WARM/MOIST AIR TO CNTRL
PART OF NATION WITH PW VALUES WELL ABV 1 INCH. AS TROF SLIDES EVER
CLOSER TO CWA THRU THE AFTN EXPECT MOISTURE TO INCRS TO OVR 1.00
INCHES. THIS HELPS TO INCRS DWPT VALUES INTO THE 50S AND PRECLUDE
FIRE WX CONCERNS FOR TDA AS OPPOSED TO YDA.
IN ADDITION AN INCRS IN CLDS FM THE APPCHG SYSTEM WL SPREAD MOCLDY
SKIES TO WRN ZONES DRG THE AFTN HRS WITH A HIGH THIN CIRRUS EXPECTED
RMNDR OF AREA. THIS WL HELP TO TEMPER TEMP RISE TDA WITH MOST HIGHS
IN THE M70S.
WARM ADVECTION WL COMBINE WITH APPCHG UL FRCG AND LGT SHOWERS WL
START TO DVLP ACRS THE WEST BTWN 18Z AND 21Z THIS AFTN BFR SLIDING
EAST, PERHAPS GETTING AS FAR EAST AS THE I-81 CORRIDOR IN CNY BY 00Z
TONIGHT. MODELS AGREE WITH PLACEMENT OF CDFNT AT 00Z TONIGHT BUT
DIFFER WITH REGARD TO QPF WITH GFS MUCH MORE BULLISH THAN EURO AND
NAM. WUD CERTAINLY NOT BE SURPRISED TO SEE A SPRINKLE IN CNTRL SXNS
OF CWA UNDER STRONG WARM ADVECTION BUT FEEL THE CRUX OF THE PCPN WL
BE FELT IN THE FINGER LKS REGION THIS AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
4 AM UPDATE...
POPS INCRS TONIGHT FM WEST TO EAST AS FRCG FM FRONT MVS CLOSER TO
CWA. LKLY POPS EXPECTED BY 06Z, THEN INCRSG TO 100 POPS BY MRNG.
GIVEN STRONG MOISTURE SURGE (THETA-E RIDGE) AND WARM AIR ADVECTION
HV GONE WITH MORE SHOWERY MENTION THRU 09Z TONIGHT. H5 LOW WL BE
SITTING UP ACRS HUDSON BAY WITH L/WV TROF BCMG NEGATIVELY TILTED TUE
MRNG. 250MB SPEED MAX WL STRENGTHEN TO +120KTS BY DAYBREAK WITH CWA
IN RIGHT-ENTRANCE REGION ARND 09Z, THUS WL GO WITH MORE OF A RAIN
SCENARIO AFT THIS TIME.
HV ADDED IN CHC FOR THUNDER DRG THE OVRNGT AS SI`S APPRCH ZERO,
MLCAPES ARND 100 J/KG AND K-INDICES > 30. 00Z MODELS AGREE THAT
CDFNT WL BE ENTERING INTO WRN ZONES BY 12Z TUESDAY.
TEMPS WL FALL THRU THE DAY TUE IN CNY AS CDFNT COMES BLASTING THRU.
MAY SEE A BRIEF RISE IN TEMPS ACRS SERN ZONES DRG THE MRNG BFR
HOLDING STEADY THEN FALLING STEADILY AFT 18Z. HV SIDED MORE WITH THE
TIMING OF THE CHANGEOVER FM RAIN TO SNOW/SLEET WITH THE GFS AND EURO
AS NAM SEEMS TO BE TOO SLOW. EXPECT ALL RAIN DRG THE MRNG HRS AND
THEN SLOWLY MIXING WITH SLEET BY EARLY AFTN ACRS THE FINGER LKS,
THEN BCMG ALL SNOW AFT 21Z IN THE FINGER LKS. PCPN WL START TO MIX
WITH SLEET AND SNOW AFT 21Z ACRS THE I-81 CORRIDOR IN NY STATE WITH
RAIN EXPECTED THRU 00Z WED IN PIKE AND SULLIVAN CNTYS.
EXPECT ALL SNOW SHOWERS TUE NGT WITH POSSIBLE EXCEPTION OF FAR SERN
ZONES EARLY AS THEY TRANSITION OVR. SNOWFALL AMNTS FM TIME OF
TRANSITION (LATE AFTN TUE) UNTIL PCPN EXITS STAGE RIGHT ARND 06Z WED
LOOKS TO BE ON THE ORDER OF 1-1.5 INCHES.
WITH H8 TEMPS PROGGED TO DROP TO NR -14C WED MRNG, EXPECT OVRNGT
LOWS TO DIP INTO THE TEENS. THIS IS UNDER STRONG NW WINDS AS WELL.
IF WINDS CAN DECOUPLE, TEMPS MAY DROP EVEN LOWER. THIS WUD PUT
RECORD LOWS IN JEOPARDY FOR THIS DATE. KBGM`S RECORD LOW IS 24F,
KAVP IS 20F AND KSYR IS 23F.
UNDER FULL SUN WITH HIPRES BUILDING IN ON WED, MAX TEMPS WL QUICKLY
CLIMB INTO THE 40S. HIGH WL SHIFT OFF TO THE EAST WED NGT, ALLOWING
RETURN FLOW TO RE-ESTABLISH ITSELF.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
315 AM UPDATE...
NO MAJOR CHANGES MADE THIS MORNING AS A FAIR AMOUNT OF MODEL
DISAGREEMENT STILL EXISTS WITH NEXT WEEKEND/S STORM SYSTEM. BEFORE
THIS HOWEVER...DRY BUT COOLER WEATHER WILL PREVAIL THROUGH THE
REMAINDER OF THE WORK WEEK AS STRONG HIGH PRESSURE REMAINS
ENTRENCHED OVER THE NORTHEAST AND EASTERN CANADA. IN TERMS OF NEXT
WEEKEND/S STORM SYSTEM...THE GFS TAKES A SFC LOW DIRECTLY OVER OUR
FCST REGION...WHILE THE ECMWF SHOWS A SFC LOW APPROACHING FROM THE
SOUTHWEST WITH THIS FEATURE GRADUALLY LOOSING STEAM AS ENERGY
TRANSFERS TO A DEVELOPING COASTAL LOW OFF THE EASTERN SEABOARD.
UNDER THE LATTER SCENARIO...MUCH OF OUR FCST REGION IS SPARED OF
APPRECIABLE RAINFALL. FOR WHAT ITS WORTH...THE CANADIAN-CMC TOO
SHOWS TRANSFERRING ENERGY ALBEIT A LITTLE FURTHER NORTH THAN THE
ECMWF. IF THIS WERE TO PANE OUT AS ADVERTISED...SOME SOME PRECIP
WOULD LIKELY WORK NORTH INTO OUR AREA. AS RESULT OF THIS THIRD
SOLUTION...WILL MAINTAIN CHC POPS ACROSS THE SOUTHERN 2/3RDS OF
THE FCST REGION FRIDAY NIGHT AND SATURDAY.
PREVIOUS LONG TERM DISCUSSION...
MEDIUM RANGE MODELS START OUT IN GOOD AGREEMENT EARLY IN THE
EXTENDED PERIOD THEN DIVERGE BY NEXT WEEKEND. INITIALLY SFC HIGH
PRES OVER NRN NEW ENGLAND AND NOVA SCOTIA WILL BRING FAIR AND COOL
WEATHER TO THE AREA WITH LOWS WED NIGHT IN THE MID TO UPPER 20S
FOLLOWED BY UPPER 20S TO MID 30S ON THURSDAY NIGHT. MAXES BOTH
THURSDAY AND FRIDAY WILL RANGE IN THE 50S WITH SOME MODIFICATION
ON FRIDAY.
FRIDAY NIGHT THROUGH SUNDAY THE OPERATIONAL GFS TAKES A SFC LOW
IN THE TN VALLEY AND TRACKS IT NORTHEAST ACROSS OUR VCNTY THEN INTO
EASTERN CANADA BY SUNDAY. A WET SCENARIO FOLLOWED BY WRAP AROUND
MOISTURE SATURDAY NIGHT INTO SUNDAY. THE ECMWF PLACES THIS FEATURE
FARTHER SOUTH AND WEAKER THEN MOVES IT OFF THE MID ATLANTIC COAST
KEEPING THE REGION BASICALLY DRY. FOLLOWED HPC GUIDANCE WHICH
KEEPS THE SYSTEM TO OUR SOUTH BUT WILL INCLUDE CHC POPS FROM
FRIDAY NIGHT THROUGH SATURDAY NIGHT FOR RAIN SHOWERS.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS OUT OF THE GATE THIS MORNING. MAIN STORY THROUGH
THE DAY WILL BE STRONG SOUTHWEST WINDS WITH GUSTS IN EXCESS OF 25
KTS POSSIBLE AT ALL SITES. FCST MODELS SHOW SOME SHWR ACTIVITY
DEVELOPING BY MID/LATE AFTERNOON...HOWEVER OVERALL CONFIDENCE IS
TO LOW AT THIS POINT TO INCLUDE IN THE FCST. MUCH BETTER CHANCES
FOR PRECIP WILL ARRIVE SHORTLY AFTER 00Z AS PRECIP SHIELD
ASSOCIATED WITH COLD FRONT APPROACHES. AS THIS OCCURS...EXPECT
CATEGORICAL DECREASES TO MVFR AND POTENTIALLY IFR CONDITIONS AS
STEADY PRECIP MOVES IN. MOST LIKELY CANDIDATES FOR IFR DURING
THE OVERNIGHT PERIOD WILL BE ITH AND BGM...WITH MVFR EXPECTED
ELSEWHERE.
OUTLOOK...
TUE...RESTRICTIONS IN SCATTERED RAIN SHOWERS AND ISOLATED THUNDER
TUESDAY MORNING...WITH RAIN CHANGING TO SNOW TUE AFTERNOON/EVENING.
TUE NGT...RESTRICTIONS POSSIBLE IN SCATTERED SNOW SHOWERS.
WED-THU-FRI...VFR.
&&
.FIRE WEATHER...
4 AM MONDAY UPDATE...
DEWPOINT TEMPERATURES WILL REMAIN FAIRLY STEADY THROUGH THE DAY
BUT TEMPERATURES ARE NOT EXPECTED TO CLIMB AS HIGH AS YESTERDAY,
LEADING TO MINIMUM RELATIVE HUMIDITY VALUES REMAINING ABOVE 40%
THROUGH THE DAY. SOUTH-SOUTHWEST WINDS WILL BE STRONG AND GUSTY
AGAIN TODAY BUT ANY FIRE WEATHER CONCERNS WILL BE PRECLUDED BY
INCREASING MOISTURE AHEAD OF AN APPROACHING COLD FRONT. WIDESPREAD
RAIN WILL MOVE IN LATE TONIGHT. COLD AIR WILL MOVE IN BEHIND THE
FRONT ON TUESDAY AFTERNOON, SWITCHING RAIN OVER TO SNOW SHOWERS
BRIEFLY ON TUESDAY NIGHT, MAINLY ACROSS CENTRAL NEW YORK.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN
NEAR TERM...PVN
SHORT TERM...PVN
LONG TERM...CMG/RRM
AVIATION...CMG
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
628 AM EDT MON APR 14 2014
.SYNOPSIS...
THE WEATHER WILL BE MILD AND DRY THROUGH MOST OF TODAY.
MEANWHILE LOW PRESSURE OVER THE CENTRAL U.S. WILL MOVE NORTHEAST
AND BRING SHOWERS TO THE AREA LATE THIS AFTERNOON INTO TONIGHT.
ON TUESDAY, A STRONG COLD FRONT WILL PASS THROUGH. LOCALLY HEAVY
RAIN WILL BE POSSIBLE AHEAD OF THE COLD FRONT WITH THE POTENTIAL
FOR ACCUMULATING SNOWS BEHIND IT ACROSS CENTRAL NEW YORK. HIGH
PRESSURE WILL BRING A RETURN TO FAIR WEATHER ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
630 AM UPDATE...
993MB SFC LOW HAS NOW MVD INTO NRN LOWER MICHIGAN WITH STRONG COLD
FRONT DRAPED BACK THRU THE MIDWEST. AS IT CROSSED CHICAGO, O-HARE
DROPPED 16 DEGREES IN ONE HOUR. THIS SYSTEM WILL EVENTUALLY CROSS
OUR AREA TOMORROW. IN THE MEANTIME HAVE HAD TO DO SOME FINAGLING
WITH TEMPS FOR TDA AS MOST OF CWA WERE WITHIN 4-5 DEGREES OF HIGH
TEMPS TDA. WENT SIGNIFICANTLY ABV GUIDANCE FOR THIS UPDATE AS MOST
LOCALES SHUD EASILY PUSH INTO THE U70S. LATEST HRRR NOW HAS
WIDESPREAD RAIN INTO WRN ZONES BY 22Z AND THIS WL NEED TO BE
MONITORED THROUGHOUT THE DAY.
PREV DISCO BLO...
155 AM UPDATE...
SPRINGTIME STORM SYSTEM THAT BROUGHT SVR WX TO THE PLAINS YDA WL BE
HEADED NORTHEAST OVR THE NEXT SEVERAL DAYS. WM FNT DRAPED ACRS SRN
ONTARIO AND NRN NY STATE EXTENDS FM SFC LOW LOCATED OVR THE QUAD
CITIES REGION. ASSOC H5 TROF IS SPINNING THRU THE CNTRL PLAINS WITH
WIDESPREAD AREA OF SHOWERS/TSTMS ALONG MS RVR.
ALL THIS MEANS WITH REGARD TO OUR WX IS A MILD SRLY FLOW CONTG TDA.
GOM IS CURRENTLY WIDE OPEN AND DRAWING IN WARM/MOIST AIR TO CNTRL
PART OF NATION WITH PW VALUES WELL ABV 1 INCH. AS TROF SLIDES EVER
CLOSER TO CWA THRU THE AFTN EXPECT MOISTURE TO INCRS TO OVR 1.00
INCHES. THIS HELPS TO INCRS DWPT VALUES INTO THE 50S AND PRECLUDE
FIRE WX CONCERNS FOR TDA AS OPPOSED TO YDA.
IN ADDITION AN INCRS IN CLDS FM THE APPCHG SYSTEM WL SPREAD MOCLDY
SKIES TO WRN ZONES DRG THE AFTN HRS WITH A HIGH THIN CIRRUS EXPECTED
RMNDR OF AREA. THIS WL HELP TO TEMPER TEMP RISE TDA WITH MOST HIGHS
IN THE M70S.
WARM ADVECTION WL COMBINE WITH APPCHG UL FRCG AND LGT SHOWERS WL
START TO DVLP ACRS THE WEST BTWN 18Z AND 21Z THIS AFTN BFR SLIDING
EAST, PERHAPS GETTING AS FAR EAST AS THE I-81 CORRIDOR IN CNY BY 00Z
TONIGHT. MODELS AGREE WITH PLACEMENT OF CDFNT AT 00Z TONIGHT BUT
DIFFER WITH REGARD TO QPF WITH GFS MUCH MORE BULLISH THAN EURO AND
NAM. WUD CERTAINLY NOT BE SURPRISED TO SEE A SPRINKLE IN CNTRL SXNS
OF CWA UNDER STRONG WARM ADVECTION BUT FEEL THE CRUX OF THE PCPN WL
BE FELT IN THE FINGER LKS REGION THIS AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
4 AM UPDATE...
POPS INCRS TONIGHT FM WEST TO EAST AS FRCG FM FRONT MVS CLOSER TO
CWA. LKLY POPS EXPECTED BY 06Z, THEN INCRSG TO 100 POPS BY MRNG.
GIVEN STRONG MOISTURE SURGE (THETA-E RIDGE) AND WARM AIR ADVECTION
HV GONE WITH MORE SHOWERY MENTION THRU 09Z TONIGHT. H5 LOW WL BE
SITTING UP ACRS HUDSON BAY WITH L/WV TROF BCMG NEGATIVELY TILTED TUE
MRNG. 250MB SPEED MAX WL STRENGTHEN TO +120KTS BY DAYBREAK WITH CWA
IN RIGHT-ENTRANCE REGION ARND 09Z, THUS WL GO WITH MORE OF A RAIN
SCENARIO AFT THIS TIME.
HV ADDED IN CHC FOR THUNDER DRG THE OVRNGT AS SI`S APPRCH ZERO,
MLCAPES ARND 100 J/KG AND K-INDICES > 30. 00Z MODELS AGREE THAT
CDFNT WL BE ENTERING INTO WRN ZONES BY 12Z TUESDAY.
TEMPS WL FALL THRU THE DAY TUE IN CNY AS CDFNT COMES BLASTING THRU.
MAY SEE A BRIEF RISE IN TEMPS ACRS SERN ZONES DRG THE MRNG BFR
HOLDING STEADY THEN FALLING STEADILY AFT 18Z. HV SIDED MORE WITH THE
TIMING OF THE CHANGEOVER FM RAIN TO SNOW/SLEET WITH THE GFS AND EURO
AS NAM SEEMS TO BE TOO SLOW. EXPECT ALL RAIN DRG THE MRNG HRS AND
THEN SLOWLY MIXING WITH SLEET BY EARLY AFTN ACRS THE FINGER LKS,
THEN BCMG ALL SNOW AFT 21Z IN THE FINGER LKS. PCPN WL START TO MIX
WITH SLEET AND SNOW AFT 21Z ACRS THE I-81 CORRIDOR IN NY STATE WITH
RAIN EXPECTED THRU 00Z WED IN PIKE AND SULLIVAN CNTYS.
EXPECT ALL SNOW SHOWERS TUE NGT WITH POSSIBLE EXCEPTION OF FAR SERN
ZONES EARLY AS THEY TRANSITION OVR. SNOWFALL AMNTS FM TIME OF
TRANSITION (LATE AFTN TUE) UNTIL PCPN EXITS STAGE RIGHT ARND 06Z WED
LOOKS TO BE ON THE ORDER OF 1-1.5 INCHES.
WITH H8 TEMPS PROGGED TO DROP TO NR -14C WED MRNG, EXPECT OVRNGT
LOWS TO DIP INTO THE TEENS. THIS IS UNDER STRONG NW WINDS AS WELL.
IF WINDS CAN DECOUPLE, TEMPS MAY DROP EVEN LOWER. THIS WUD PUT
RECORD LOWS IN JEOPARDY FOR THIS DATE. KBGM`S RECORD LOW IS 24F,
KAVP IS 20F AND KSYR IS 23F.
UNDER FULL SUN WITH HIPRES BUILDING IN ON WED, MAX TEMPS WL QUICKLY
CLIMB INTO THE 40S. HIGH WL SHIFT OFF TO THE EAST WED NGT, ALLOWING
RETURN FLOW TO RE-ESTABLISH ITSELF.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
315 AM UPDATE...
NO MAJOR CHANGES MADE THIS MORNING AS A FAIR AMOUNT OF MODEL
DISAGREEMENT STILL EXISTS WITH NEXT WEEKEND/S STORM SYSTEM. BEFORE
THIS HOWEVER...DRY BUT COOLER WEATHER WILL PREVAIL THROUGH THE
REMAINDER OF THE WORK WEEK AS STRONG HIGH PRESSURE REMAINS
ENTRENCHED OVER THE NORTHEAST AND EASTERN CANADA. IN TERMS OF NEXT
WEEKEND/S STORM SYSTEM...THE GFS TAKES A SFC LOW DIRECTLY OVER OUR
FCST REGION...WHILE THE ECMWF SHOWS A SFC LOW APPROACHING FROM THE
SOUTHWEST WITH THIS FEATURE GRADUALLY LOOSING STEAM AS ENERGY
TRANSFERS TO A DEVELOPING COASTAL LOW OFF THE EASTERN SEABOARD.
UNDER THE LATTER SCENARIO...MUCH OF OUR FCST REGION IS SPARED OF
APPRECIABLE RAINFALL. FOR WHAT ITS WORTH...THE CANADIAN-CMC TOO
SHOWS TRANSFERRING ENERGY ALBEIT A LITTLE FURTHER NORTH THAN THE
ECMWF. IF THIS WERE TO PANE OUT AS ADVERTISED...SOME SOME PRECIP
WOULD LIKELY WORK NORTH INTO OUR AREA. AS RESULT OF THIS THIRD
SOLUTION...WILL MAINTAIN CHC POPS ACROSS THE SOUTHERN 2/3RDS OF
THE FCST REGION FRIDAY NIGHT AND SATURDAY.
PREVIOUS LONG TERM DISCUSSION...
MEDIUM RANGE MODELS START OUT IN GOOD AGREEMENT EARLY IN THE
EXTENDED PERIOD THEN DIVERGE BY NEXT WEEKEND. INITIALLY SFC HIGH
PRES OVER NRN NEW ENGLAND AND NOVA SCOTIA WILL BRING FAIR AND COOL
WEATHER TO THE AREA WITH LOWS WED NIGHT IN THE MID TO UPPER 20S
FOLLOWED BY UPPER 20S TO MID 30S ON THURSDAY NIGHT. MAXES BOTH
THURSDAY AND FRIDAY WILL RANGE IN THE 50S WITH SOME MODIFICATION
ON FRIDAY.
FRIDAY NIGHT THROUGH SUNDAY THE OPERATIONAL GFS TAKES A SFC LOW
IN THE TN VALLEY AND TRACKS IT NORTHEAST ACROSS OUR VCNTY THEN INTO
EASTERN CANADA BY SUNDAY. A WET SCENARIO FOLLOWED BY WRAP AROUND
MOISTURE SATURDAY NIGHT INTO SUNDAY. THE ECMWF PLACES THIS FEATURE
FARTHER SOUTH AND WEAKER THEN MOVES IT OFF THE MID ATLANTIC COAST
KEEPING THE REGION BASICALLY DRY. FOLLOWED HPC GUIDANCE WHICH
KEEPS THE SYSTEM TO OUR SOUTH BUT WILL INCLUDE CHC POPS FROM
FRIDAY NIGHT THROUGH SATURDAY NIGHT FOR RAIN SHOWERS.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS EXPECTED THROUGH THE MAJORITY OF THE FCST PERIOD
AS STRONG SOUTHWEST FLOW PREVAILS AHEAD OF AN APPROACHING COLD
FRONT. WINDS WILL AGAIN INCREASE AFTER SUNRISE WITH SOLID GUSTS TO
NEAR/SLIGHTLY ABOVE 25 KTS THROUGH THE DAY TODAY. BEFORE THIS
HOWEVER...STRONG WINDS OFF THE DECK WILL LEAD TO LOW-LEVEL WIND
SHEAR AT ALL SITES UNTIL MIXING COMMENCES AFTER SUNRISE. IN TERMS OF
PRECIP CHANGES...BEST POTENTIAL EXISTS AT SYR/RME/ITH/ELM AFTER 21
OR SO...WITH BEST ORGANIZED RAIN POTENTIAL HOLDING OFF UNTIL AFTER
00Z AT ALL CNY SITES. DRY CONDITIONS ANTICIPATED AT AVP THROUGH THE
FCST PERIOD. AT ITH AND BGM...EXPECT DEVELOPING MVFR CIGS AFTER
00Z AS FRONTAL BOUNDARY APPROACHES.
OUTLOOK...
TUE...RESTRICTIONS IN SCATTERED RAIN SHOWERS AND ISOLATED THUNDER
TUESDAY MORNING...WITH RAIN CHANGING TO SNOW TUE AFTERNOON/EVENING.
TUE NGT...RESTRICTIONS POSSIBLE IN SCATTERED SNOW SHOWERS.
WED-THU-FRI...VFR.
&&
.FIRE WEATHER...
4 AM MONDAY UPDATE...
DEWPOINT TEMPERATURES WILL REMAIN FAIRLY STEADY THROUGH THE DAY
BUT TEMPERATURES ARE NOT EXPECTED TO CLIMB AS HIGH AS YESTERDAY,
LEADING TO MINIMUM RELATIVE HUMIDITY VALUES REMAINING ABOVE 40%
THROUGH THE DAY. SOUTH-SOUTHWEST WINDS WILL BE STRONG AND GUSTY
AGAIN TODAY BUT ANY FIRE WEATHER CONCERNS WILL BE PRECLUDED BY
INCREASING MOISTURE AHEAD OF AN APPROACHING COLD FRONT. WIDESPREAD
RAIN WILL MOVE IN LATE TONIGHT. COLD AIR WILL MOVE IN BEHIND THE
FRONT ON TUESDAY AFTERNOON, SWITCHING RAIN OVER TO SNOW SHOWERS
BRIEFLY ON TUESDAY NIGHT, MAINLY ACROSS CENTRAL NEW YORK.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN
NEAR TERM...PVN
SHORT TERM...PVN
LONG TERM...CMG/RRM
AVIATION...CMG
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1055 AM EDT MON APR 14 2014
.SYNOPSIS...SOUTHERLY FLOW WILL ADVECT AN INCREASINGLY MOIST AND
UNSTABLE AIRMASS INTO THE REGION TODAY AND TONIGHT AS A POTENT UPPER
LEVEL TROUGH AND ASSOCIATED COLD FRONT TRACK EAST INTO THE TENNESSEE
VALLEY. THE COLD FRONT WILL PROGRESS EAST THROUGH THE CAROLINAS
TUESDAY AFTERNOON AND EVENING.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1055 AM MONDAY...
THE 12Z KGSO SOUNDING WAS CAPPED TO DEEP CONVECTION WITH A GOOD CAP
BETWEEN 850MB AND 700MB...AND CONSIDERABLE MOISTURE ABOVE 500MB. THE
LATEST SPC MESOANALYSIS SHOWED A RELATIVE MINIMUM OF PRECIPITABLE
WATER VALUES OVER MUCH OF CENTRAL NORTH CAROLINA ALTHOUGH WITH A
NARROW RIBBON OF INCREASING VALUES...JUST BELOW AN INCH...EXTENDING
FROM SOUTH CAROLINA INTO THE SOUTHWEST PIEDMONT. HIGH PRESSURE
EXTENDING OVER CENTRAL NORTH CAROLINA FROM THE EAST WAS PROVIDING A
MOIST...SOUTHERLY FLOW OFF OF THE ATLANTIC INTO THE AREA...WITH
SURFACE DEW POINTS IN THE MID 50S TO AROUND 60.
TO OUR WEST...THE SURFACE LOW WILL INCREASE IN STRENGTH DUE TO THE
OFFSET UPPER LEVEL TROUGH TO THE WEST. DIVERGENCE ALOFT IS
DECREASING THE SURFACE PRESSURE AHEAD OF THE FRONT BRINGING IN
CYCLONIC VORTICITY ADVECTION IN A SHORT WAVE AHEAD OF THE FRONT.
SURFACE WINDS ARE SOUTHERLY AND HAVE INCREASED THE DEWPOINTS AS
MOIST AND WARM AIR IS ADVECTED INTO THE AREA AHEAD OF THE COLD
FRONT. WARM ADVECTION ALONG WITH CYCLONIC VORTICITY ADVECTION WILL
BRING AN INCREASE IN LIFT AND CLOUD COVER OVER THE AREA AND AN
INCREASED CHANCE FOR PRECIPITATION AND CONVECTION. A FEW SHOWERS ARE
POPPING UP TO OUR WEST AND ARE EXPECTED TO INCREASE IN NUMBER AND
EVENTUALLY PRODUCE CONVECTIVE STORMS AS THE COLD FRONT MOVES
EASTWARD.
THE 12Z UPPER-AIR ANALYSIS SHOWED SOME DIFFLUENCE TO OUR WEST AND
THIS IS FORECAST TO CONTINUE THIS AFTERNOON INTO TONIGHT AS A SERIES
OF MID-LEVEL WAVES MOVE THROUGH CENTRAL NORTH CAROLINA. THE LATEST
RAP SHOWS THE MID-LEVEL CAP WEAKENING WITH TIME THROUGH EARLY
AFTERNOON...AND SLIGHT 700MB COOLING ON THE 12Z UPPER-AIR ANALYSIS
WOULD SUGGEST THIS...ALTHOUGH THE RAP ALSO FORECASTS A MODEST
INCREASE IN THOSE MID-LEVEL TEMPERATURES LATE IN THE DAY. WITH THE
MOISTURE IN PLACE...MODEST INSTABILITY WITH SURFACE-BASED CAPE
AROUND 400J/KG AND MLCAPE IN THHIGHS TODAY WERE LOWERED ABOUT A
DEGREE IN THE TRIAD DUE TO EXPECTED CLOUD COVER...AND RAISED ABOUT A
DEGREE TOWARD INTERSTATE 95 DUE TO THINNER CLOUDS FOR A LONGER
PERIOD OF TIME THERE. E LOWEST KM AROUND 200J/KG...AND SOME LIFT
WITH THE MID-LEVEL SHORTWAVES...AS THE CAP ERODES ANTICIPATE
ISOLATED TO SCATTERED SHOWERS DEVELOPING...WITH AN ISOLATED
THUNDERSTORM POSSIBLE. AS THE MID-LEVEL TEMPERATURES WARM SLIGHTLY
LATER...THIS COULD FOR A TIME INHIBIT MORE DEEP CONVECTION...AND
THIS SCENARIO IS NOTED BY MORE THAN ONE WRF MODEL AS WELL AS IMPLIED
BY RAP QPF.
MOISTENING OF THE UPPER LEVELS WILL INCREASE CLOUD DEPTH AND ALLOW
FOR LIFTING OVER A DEEPER LAYER. THIS WILL INCREASE THE CHANCE FOR
SOME DEEP MOIST CONVECTION AND SHOWERS OVER THE AREA...
HOWEVER...THE STRONGEST LIFTING WILL STAY TO THE WEST WITH THE COLD
FRONT. CONVECTION SHOULD BECOME MORE NUMEROUS IN COVERAGE OVER
CENTRAL NORTH CAROLINA THIS EVENING INTO TONIGHT DUE TO ONGOING
MOISTENING...STRENGTHENING HEIGHT FALLS...AND PERIODIC DPVA IN SW
FLOW ALOFT...ESPECIALLY IN WESTERN PORTIONS OF THE STATE.
HOWEVER...SEVERAL LARGE MESOSCALE CONVECTIVE SYSTEMS ARE EXPECTED TO
DEVELOP UPSTREAM IN THE DEEP SOUTH IN THIS PERIOD...ONE THIS
AFTERNOON AND PERHAPS ANOTHER LATE TONIGHT...AND HOW THESE FEATURES
EVOLVE/INTERACT WITH THE LARGER SCALE PATTERN WILL MOST CERTAINLY
AFFECT PRECIP CHANCES DOWNSTREAM IN CENTRAL NC...LENDING A FAIR
AMOUNT OF UNCERTAINTY TO THE PRECISE COVERAGE/AMOUNT OF CONVECTION
TONIGHT.
THE INCREASED CLOUD COVER WILL RESULT IN A SLIGHT DECREASE...ROUGHLY
A DEGREE...FOR HIGH TEMPERATURES FOR THE WESTERN PART OF CENTRAL
NORTH CAROLINA. HIGHS WERE RAISED ABOUT A DEGREE TOWARD INTERSTATE
95 WHERE THERE WILL BE MORE PERIODS OF THINNER CLOUDS AND MORE
SUNLIGHT HITTING THE GROUND. A VERY MOIST AND BREEZY SOUTHERLY FLOW
THROUGHOUT THE WARM SECTOR IN THE CAROLINAS WILL MAINTAIN TEMPS IN
THE MID 60S OVERNIGHT.
THOUGH QUITE CONDITIONAL/UNCERTAIN...IF DEEP CONVECTION DEVELOPS AND
PROGRESSES INTO CENTRAL NC THIS EVENING AND TONIGHT...AN ISOLATED
SEVERE STORM WOULD BE POSSIBLE GIVEN INCREASINGLY IMPRESSIVE
LOW/DEEP-LAYER SHEAR.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
AS OF 330 AM MONDAY...
TUE/TUE NIGHT: EXPECT CHANCES FOR CONVECTION NEAR 100% ON TUESDAY AS
A POTENT UPPER LEVEL TROUGH AND ATTENDANT COLD FRONT PROGRESS
THROUGH THE CAROLINAS IN THE PRESENCE OF A MOIST AND UNSTABLE
AIRMASS VIA PERSISTENT SOUTHERLY LOW-LEVEL FLOW OFF THE ATLANTIC. AT
THIS TIME...FROPA IS EXPECTED TO OCCUR BETWEEN 18-21Z IN THE NW
PIEDMONT AND BY 00-03Z IN THE COASTAL PLAIN...WITH STRONG COLD
ADVECTION THEREAFTER. EXPECT HIGHS RANGING FROM THE MID/UPPER 60S IN
THE NW PIEDMONT WHERE CLOUD COVER/CONVECTION WILL PREVENT MUCH OF A
RISE IN TEMPS PRIOR TO FROPA...TO THE MID/UPPER 70S POTENTIALLY IN
THE COASTAL PLAIN WHERE FROPA WILL BE LATER. STRONG LOW/DEEP LAYER
SHEAR...FAVORABLE DIURNAL TIMING...AND MARGINAL TO MODERATE
DESTABILIZATION (500-1000 J/KG MLCAPE) CERTAINLY INDICATE A
POTENTIAL FOR SEVERE THUNDERSTORMS...THOUGH THE PRECISE NATURE OF
THE THREAT IS STILL DIFFICULT TO ASCERTAIN GIVEN A POTENTIAL FOR
UPSTREAM CONVECTION /MCS ACTIVITY/ LATE TONIGHT AND TUE MORNING.
DAMAGING WINDS AND ISOLD TORNADOES WILL BE THE PRIMARY THREAT(S)...
THE LATTER OF WHICH COULD BE FURTHER ENHANCED BY BACKED SFC WINDS
/LARGE CLOCKWISE CURVED HODOGRAPHS/ POSSIBLE ON THE EASTERN
PERIPHERY OF ANY SFC WAVES WHICH COULD DEVELOP ALONG THE FRONT IN
CENTRAL/EASTERN NC...PARTICULARLY ALONG AND EAST OF I-95 WHERE
DIURNAL TIMING AND DESTABILIZATION WILL BE MOST FAVORABLE. STRONG
COLD ADVECTION WILL RESULT IN A STARK CONTRAST IN TEMPERATURES IN
COMPARISON TO THE PREVIOUS FEW DAYS...WITH LOWS RANGING FROM THE
LOWER TO UPPER 30S...POTENTIALLY NEAR FREEZING ALONG/WEST OF HWY 1.
A FREEZE WATCH MAY BE NEEDED FOR PORTIONS OF THE AREA TUE NIGHT/WED
MORNING. SINCE LOWS WILL PRIMARILY DEPEND UPON COLD ADVECTION...
SUFFICIENT UNCERTAINTY EXISTS TO PRECLUDE ANY FROST/FREEZE PRODUCT
ISSUANCE AT THIS TIME. -VINCENT
AS OF 245 AM MONDAY...RISING HEIGHTS ALOFT/DNVA AND ASSOCIATED
STRONG SUBSIDENCE WILL RESULT IN FURTHER DEEP LAYER DRYING
WED...FOLLOWED BY GENERALLY NEUTRAL VERTICAL MOTION BUT WITH STILL A
RESIDUALLY DRY AND STRONGLY CAPPED REGIME OVER OUR REGION. SURFACE
HIGH PRESSURE WILL CONSEQUENTLY BECOME UNSEASONABLY STRONG - INTO
THE 1040-1045 MB RANGE AS IT BUILDS FROM THE OH VALLEY TO NEW
ENGLAND. UNSEASONABLY COOL NORTHEASTERLY FLOW...WITH TEMPERATURES 10
TO 20 DEGREES BELOW AVERAGE...WILL RESULT OVER CENTRAL NC. INITIALLY
CLEAR SKIES WED WILL BECOME PARTLY CLOUDY...TO PERHAPS MOSTLY SO IN
THE COASTAL PLAIN...BY THU AFTERNOON...AS MOISTURE FLAT
STRATOCUMULUS IS ADVECTED INLAND BENEATH THE CAP.
PROJECTED LOW LEVEL THICKNESS VALUES IN THE 1300-1310 METER RANGE AT
12Z THU AND CLEAR SKIES WOULD SUPPORT SUB-FREEZING TEMPERATURES THU
MORNING...BUT CONFIDENCE IS LOW REGARDING THE DEGREE OF CALM GIVEN A
PROJECTED 4-6 MB RISE IN MSL PRESSURE WITH THE STRENGTHENING HIGH
WED NIGHT. WILL ADJUST LOWS TO REFLECT MOSTLY LOWER TO MIDDLE
30S...COOLEST WEST...BUT THESE MAY NEED FURTHER DOWNWARD ADJUSTMENT
(OR AT LEAST OPEN THE RANGE) TO INCLUDE SOME UPPER 20S (AROUND
RECORD LOWS) IF IT INDEED APPEARS ANY PERIOD OF APPRECIABLE CALM
WILL BE ATTAINED. SIMILARLY COOL IN THE MIDDLE 50S WED...WHICH MAY
THREATEN THE RECORD LOW MAX OF 56 DEGREES AT KFAY FOR THE DATE. SEE
CLIMATE SECTION BELOW. SLOW MODERATION TO AROUND 60 AND 40 DEGREES
FOR HIGHS AND LOWS...RESPECTIVELY...THU AND THU NIGHT. -MWS
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 300 AM MONDAY...
THOUGH MODEL SOLUTION SPREAD REMAINS ABOVE AVERAGE DURING THE LONG
TERM...THE EMERGING SIGNAL FROM THE MAJORITY OF BOTH THE ENSEMBLE
AND SOLUTIONS OS FOR A DOMINANT NORTHERN STREAM ACROSS THE NORTHERN
THIRD OF THE US...ONE THAT WILL INCLUDE AT LEAST ONE PRIMARY
SHORTWAVE TROUGH AND ACCOMPANYING SURFACE CYCLONE FORECAST TO CROSS
THE UPPER MIDWEST AND LOWER GREAT LAKES FRI-SAT - A STORM TRACK THAT
WOULD RESULT IN A MOSTLY DRY COLD FRONTAL PASSAGE SAT-SAT NIGHT AS
DEPICTED BY AT LEAST THE LAST SEVERAL RUNS OF THE GFS. ON THE OTHER
HAND...THE LAST COUPLE OF RUNS OF THE OPERATIONAL ECMWF...WHICH HAVE
MINIMAL SUPPORT FROM THE EC ENSEMBLE MEAN...SUGGEST MORE IN THE WAY
OF SOUTHERN STREAM TROUGHING/INTERACTION THAT WOULD RESULT IN SOME
DEGREE OF COASTAL CYCLOGENESIS AND A WETTER PATTERN FOR AT LEAST THE
EASTERN HALF OF NC DURING THE SAME TIME FRAME. IN EITHER
SCENARIO...THE BEST CHANCES OF RAIN WOULD BE LATE FRI NIGHT-SAT
EVENING...SO MENTIONABLE POP WILL BE CONFINED TO THAT TIME UNTIL A
CLEARER PICTURE EMERGES.
&&
.AVIATION /12Z MONDAY THROUGH SATURDAY/...
AS OF 600 AM MONDAY...
24-HR TAF PERIOD: LOW-LEVEL MOISTENING /WARM ADVECTION/ IS EXPECTED
TO RESULT IN THE RAPID DEVELOPMENT OF MVFR OR IFR CEILINGS BY 12-15Z
ACROSS MUCH OF CENTRAL NC. SHALLOW CONVECTION (SHRA) WITH TOPS
AROUND 10 KFT WILL BE POSSIBLE THROUGH EARLY AFTERNOON IN ASSOC/W AN
ONSHORE FLOW IN THE LOWER-LEVELS...WITH ISOLD TO SCT SHOWERS AND
THUNDERSTORMS POSSIBLE BY LATE THIS AFTERNOON AND EVENING IN ADVANCE
OF A COLD FRONT PROGRESSING EAST INTO THE TN VALLEY. THERE SHOULD BE
SOME MARGINAL IMPROVEMENT TO CEILINGS IN ASSOC/W DIURNAL HEATING...
HOWEVER...DUE TO CONTINUED LOW-LEVEL MOISTENING CEILINGS MAY REMAIN
IN THE MVFR CATEGORY...AT OR BELOW 2000 FT AGL. EXPECT CEILINGS TO
DETERIORATE TO IFR/LIFR TONIGHT ALONG WITH AN INCREASING LIKELIHOOD
OF SHOWER ACTIVITY IN ADVANCE OF THE APPROACHING COLD FRONT.
SOUTHERLY WINDS AT 7-12 KT EARLY THIS MORNING WILL INCREASE TO 10-15
KT WITH GUSTS UP TO 22-25 KT DURING THE DAY...LIKELY REMAINING
BREEZY AND GUSTING UP TO 20 KT OVERNIGHT AS THE MSLP GRADIENT
TIGHTENS FROM THE WEST.
LOOKING AHEAD: ADVERSE AVIATION CONDITIONS ASSOCIATED WITH
WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED ON TUESDAY AS THE
AFOREMENTIONED COLD FRONT PROGRESSES EAST ACROSS THE CAROLINAS.
ISOLD SEVERE THUNDERSTORMS WILL BE POSSIBLE...ESPECIALLY AT THE
RDU/FAY/RWI TERMINALS. SOUTHERLY OR SSW WINDS AT 15 KT WITH GUSTS UP
TO 25 KT CAN BE EXPECTED IN ADVANCE OF THE FRONT THROUGH 18Z
TUE...BECOMING NW/NNW AT 15 KT WITH GUSTS UP TO 25 KT BETWEEN
ROUGHLY 18-21Z TUE AFTERNOON (INT/GSO) TO 00-03Z WED (FAY/RWI).
IFR/LIFR CEILINGS MAY LINGER FOR A WHILE IN THE WAKE OF THE FRONTAL
PASSAGE...EVENTUALLY CLEARING FROM WEST-EAST AND BECOMING VFR AFTER
MIDNIGHT WED MORNING. VFR CONDITIONS WILL PREVAIL IN THE WAKE OF THE
FRONT WED-FRI. -VINCENT
&&
.CLIMATE...
THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING...
AND THE RECORD LOW MAXIMUM TEMPERATURES FOR THU:
WED 04/16 THU 04/17
LOW/YEAR LOW MAX/YEAR LOW/YEAR
FAY: 28/1943 56/1950 31/1953
GSO: 25/1943 48/1929 29/1953
RDU: 28/1950 46/1890 29/1962
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...DJF/SR/VINCENT
SHORT TERM...VINCENT
LONG TERM...MWS
AVIATION...VINCENT
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
637 AM EDT MON APR 14 2014
.SYNOPSIS...
STRONG COLD FRONT MONDAY NIGHT. HIGH PRESSURE REST OF THE WORK
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
BUMPED UP THE TIMING OF THE POPS IN A FEW ISOLATE WARM ADVECTION
SHOWERS THIS MORNING. OTHERWISE...NO MAJOR CHANGES TO THE
FORECAST.
PREVIOUS DISCUSSION...
00Z RUN OF THE NAM CAME OUT WITH A DISTINGUISHED LINE OF CONVECTION
WELL AHEAD OF THE COLD FRONT AND THE MID AND UPPER LEVEL TROUGH
AXES. GFS CAME IN SUPPORTING THE SAME FEATURE...WITH THE HRRR IN
LINE AS WELL AS THE LINE COMES INTO THE SCOPE OF THAT MODEL/S
FORECAST RANGE. THIS IS THE ONLY MAJOR CHANGE TO THE FORECAST. SPC
KEEPS THE SLIGHT RISK OF SEVERE WEATHER WELL TO THE SOUTH THANKS TO
LOW DEWPOINTS CONTRIBUTING TO LOW SURFACE BASED CAPE. A DEVELOPING
WAVE ALONG THE FRONT WILL KEEP THE PRECIPITATION CHANCES ENHANCED
THROUGH THE MONDAY NIGHT PERIOD...WITH THE HINTS OF CLEARING COMING
IN THE NORTHWEST ZONES AT 12Z TUESDAY IN THE FORM OF POPS DROPPING
TO CHANCE.
AFTER A VERY WARM MORNING...TEMPERATURES WILL PUSH THE 80F MARK
AGAIN TODAY...COOLER WITHOUT MUCH SUN TO SPEAK OF...BUT STILL WELL
ABOVE NORMAL IN THE WARM SECTOR.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
GOOD MODEL AGREEMENT ON TIMING OF THE STRONG COLD FRONT EXITING THE
MOUNTAINS EARLY TUESDAY MORNING...FOLLOWED BY MOSTLY FALLING
TEMPERATURES DURING THE DAY. POST FRONTAL PRECIPITATION WILL END
FROM WEST TO EAST DURING THE DAY...WITH MODELS ALSO AGREEING ON THE
EXIT TIMING OF THE DEEPER MOISTURE AND PRECIP WITH THE SYSTEM. BY
DAYS END ONLY A SLIGHT CHANCE WILL LINGER IN THE NORTHERN
MOUNTAINS...ENDING BY MIDNIGHT.
THE BIG CHALLENGE IS THE NON DIURNAL TEMPERATURE CURVE DURING
TUESDAY...IN THE VERY STRONG COLD ADVECTION AND UNUSUALLY COLD
AIRMASS FOR THIS TIME OF YEAR...AND THUS THE PROSPECTS OF RAIN TO
SNOW. GIVEN THE COLD MODEL CONSENSUS ALOFT WHICH WOULD SUPPORT A
CHANGEOVER TO SNOW FROM WEST TO EAST TOWARD THE END OF THE
PRECIPITATION...THE ISSUE WILL BE THE BOUNDARY LAYER TEMPERATURES.
MODELS DO SHOW STRONG TEMPERATURE FALLS IN THE MORNING AND TENDING
TO LEVEL OUT FOR A TIME IN THE LOW LANDS IN THE AFTERNOON...BEFORE
FALLING AGAIN TUESDAY NIGHT. THIS IS REASONABLE FOR THIS TIME OF
YEAR...AND ESPECIALLY IN THE WEST AND CENTRAL AS PRECIPITATION ENDS
EARLIER IN THE DAY. WILL GO WITH THE NAM MOS GUIDANCE...MAINLY
BECAUSE IT BEST SHOWS A BREAK IN THE TEMPERATURE FALLS DURING THE
AFTERNOON...ESPECIALLY WEST AND CENTRAL. THUS...BELIEVE ANY
MIX/CHANGEOVER TO SNOW IN THE LOW LANDS WILL BE BRIEF BEFORE THE
PRECIPITATION ENDS WITH NO ACCUMULATIONS...AS SURFACE TEMPERATURES
WILL STILL BE ABOVE FREEZING AND THE GROUND QUITE WARM. IN THE
CENTRAL AND NORTHERN MOUNTAINS...THERE WILL BE A CHANGEOVER TO SNOW
DURING THE AFTERNOON...BUT ACCUMULATIONS WILL LIKELY BE AN INCH OR
LESS AND MOSTLY CONFINED TO THE HIGHER ELEVATIONS. LOOK FOR
TEMPERATURES TO START OUT TUESDAY MORNING IN THE 50S EAST AND NEAR
40 FAR WEST...REACHING BY EVENING THE LOW TO MID 30S MOST OF THE LOW
LANDS AND BELOW FREEZING ABOVE 2000 FEET.
WHILE SNOW SHOWERS TAPER OFF EARLY TUESDAY NIGHT IN THE MOUNTAINS...
CLEARING FOLLOWS MORE SLOWLY WITH THE COLD ADVECTION AND UPSLOPE
FLOW IN THE MOUNTAINS. STILL...IT SHOULD BECOME MOSTLY CLEAR EARLY
ENOUGH AS DRY HIGH PRESSURE BUILDS IN RAPIDLY FROM THE WEST...AND
ALLOW TEMPERATURES TO FALL WELL BELOW FREEZING IN ALL LOCATIONS.
HOWEVER...BELIEVE THE MODELS MAY BE A BIT ON THE LOW SIDE AS THEY
FORECAST A RUN FOR RECORD LOWS TUESDAY NIGHT. FOR NOW...WILL KEEP
OUR MINS A COUPLE OF DEGREES ABOVE THE MOS...BUT STILL WELL BELOW
FREEZING.
THEREAFTER...HIGH PRESSURE SLIDES ACROSS WITH ABUNDANT SUNSHINE
WEDNESDAY AND THURSDAY...ALONG WITH A WARMING TREND. WITH DRY AIR
AND LIGHT WINDS WEDNESDAY NIGHT...TEMPERATURES COULD FALL BELOW
FREEZING AGAIN.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
SW FLOW DOMINATES THROUGH FRIDAY BEFORE S/W TROF TRIES TO CREATE FOR
AN UNSETTLED SATURDAY. DUE TO CONTINUED DIFFERENCES REGARDING
AMPLITUDE AND STRENGTH OF SURFACE FEATURES...HAVE STAYED CLOSE TO
WPC PREFERRED SOLUTION WITH THREAT FOR SHRA FRIDAY NIGHT AND
SATURDAY.
FOR TEMPS...A WARMING TREND WILL BE NOTED TO ROUND OUT THE WORK
WEEK...BEFORE COOLER BUT MORE SEASONAL AIR ARRIVES FOR THE WEEKEND.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
SHOWERS WILL MOVE IN OVER THE NEXT FEW HOURS...AND INTO THE
WESTERN TERMINALS AFTER 15Z. TSRA POSSIBLE TODAY...BUT CANNOT PUT
IN PREVAILING CONDITIONS AND HAVE OPTED AGAIN FOR THE VCTS/CB
CODING IN THE TAFS. THIS IS IN PART DUE TO AN ATMOSPHERE THAT IS
NOT THE MOST CONDUCIVE BECAUSE OF MODEST INSTABILITY.
STILL...ISOLATED TO SCATTERED TSRA WILL EXIST...AND A TEMPO OR TWO
IN AN AMENDMENT IS LIKELY.
MVFR CEILINGS ARE THE BEST BET IN THE WARM SECTOR AHEAD OF THE
COLD FRONT WITH SHRA/TSRA. SAME WITH THE VISIBILITIES IN
PRECIPITATION. BRIEF IFR IS POSSIBLE.
WINDS AHEAD OF THE FRONT WILL GUST TO 20KTS WITH THE OCCASIONAL
25KT GUST OUT OF THE SOUTH. A SHIFT TO THE WEST NORTHWEST CAN BE
EXPECTED BEHIND THE FRONT...WHICH WILL PASS TONIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z TUESDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: CONVECTION TIMING AND BRIEF FLIGHT CATEGORY
BOUNCES COULD LEAD TO TEMPOS AND AMENDMENTS. MAY NEED PREVAILING
TSRA.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22
EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z TUESDAY...
IFR CONDITIONS EXPECTED LATE MONDAY NIGHT UNDER MODERATE RAIN
SHOWERS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/26
NEAR TERM...26
SHORT TERM...JMV
LONG TERM...30
AVIATION...26
AREA FORECAST DISCUSSION
NWS NORMAN OK
1011 AM CDT MON APR 14 2014
.UPDATE...
UPDATE TO PRECIP FORECAST...
&&
.DISCUSSION...
LIGHT SNOW CONTINUES TO FALL ACROSS PORTIONS OF NRN AND CENTRAL
OK... WITH AN AREA OF SNOW SLOWLY MOVING E/SE ACROSS PORTIONS OF
THE OKC METRO. IMPACTS ARE EXPECTED TO BE LIMITED... OKDOT
TRAFFIC CAMS AND REPORTS VIA SOCIAL MEDIA SHOW LIGHT SNOW
FALLING... WITH VISIBILITIES DROPPING NEAR 1 TO 1 1/2 MILES.
UPDATED FORECAST TO REFLECT CURRENT PATH OF SNOW... WITH -RA/SN
MIX POSSIBLE SOUTH OF THE I-44/40 CORRIDOR... CONSIDERING
SFC/BL TEMPS AND RECENT 15Z OBS FROM KCSM AND KHBR... REPORTING
UNKNOWN PRECIP. RAP BUFR SOUNDINGS SHOW BL TEMPS WARMING SLOWLY
THROUGH NOON... WITH DRIER AIR MOVING IN AS THE SFC HIGH ACROSS KS
CONTINUES TO SINK SWRD ACROSS THE SRN PLAINS. EFFECTS OF THIS ARE
ALREADY BEING SEEN ACROSS FAR NWRN OK.
PRECIP... SN... RA/SN WILL CONTINUE AHEAD OF THE SFC HIGH... WHERE
A DECENT REGION OF ISENTROPIC ASCENT RESIDES WITHIN THE 290-295K
LEVEL... SYNONYMOUS WITH THE BEST MOISTURE WITHIN THE 850 TO 700
MB LEVEL. PRECIP WILL CONTINUE TO EXIT TO THE EAST THROUGH NOON...
AS THE H500 TROUGH CONTINUES TO TRACK EWRD AND THE SFC HIGH
SETTLES INTO THE REGION THIS AFTN.
JTK
&&
.PREV DISCUSSION... /ISSUED 618 AM CDT MON APR 14 2014/
AVIATION...
MVFR CIGS WILL REMAIN WIDESPREAD THROUGH THE EARLY MORNING. LIGHT
RAIN/SNOW WILL CONTINUE TO MOVE THROUGH NRN HALF OF OK THIS AM.
CIG/VSBYS MAY DROP TO IFR BRIEFLY AT NRN SITES AS THE HEAVIER PRCP
MOVES THROUGH. PRECIP SHOULD END BY LATE MORNING WITH CONDITIONS
IMPROVING TO VFR BY AFTN. STRONG N WINDS WITH FREQUENT GUSTS OVER
30 KTS WILL PERSIST THROUGH THE DAY...BUT SHOULD DIMINISH RAPIDLY
EARLY THIS EVENING.
PREV DISCUSSION... /ISSUED 404 AM CDT MON APR 14 2014/
DISCUSSION...
BAND OF SNOW FROM TX PANHANDLE INTO NW CORNER OF THE FA CONTINUES
TO MOVE STEADILY EWD. SNOWFALL RATES IN THIS BAND SUFFICIENT FOR
SOME LIGHT ACCUMS DESPITE WARM GROUND TEMPS AND AIR TEMPS RIGHT AT
OR SLIGHTLY ABOVE FREEZING. WILL CONTINUE THE WINTER WX ADVY
THROUGH THE EARLY MORNING. BEST CHANCES FOR PRECIP WILL REMAIN
ACROSS THE NRN HALF OF THE FA THIS MORNING AS MID LEVEL TROUGH
MOVES THROUGH. TEMP PROFILES WILL BE COLD ENOUGH FOR SNOW OR
RAIN/SNOW MIX OVER MUCH OF THE NRN HALF OF THE FA THIS MORNING.
PRECIP SHOULD SHUT OFF BY AFTERNOON AS TROUGH TRANSLATES INTO ERN
OK. STRONG NORTH WINDS WILL CONTINUE THROUGH TODAY AND WILL LEAVE
WIND ADVY IN PLACE.
WINDS WILL DROP OFF QUICKLY THIS EVENING AND REMAIN LIGHT
OVERNIGHT AS SURFACE RIDGE SETTLES OVER THE SRN PLAINS. WITH
MOSTLY CLEAR SKIES AND LIGHT WINDS A COLD NIGHT IS IN STORE WITH
BELOW FREEZING TEMPS EXPECTED AREAWIDE AND FREEZE/HARD FREEZE
WARNINGS ARE IN EFFECT. WARMER TEMPS EXPECTED TUESDAY WITH THE
RETURN OF SLY LOW LEVEL FLOW.
ANOTHER S/W TROUGH MOVES IN FROM THE NW AROUND MIDWEEK BRINGING
RAIN CHANCES AND ANOTHER FRONT. DRY WEATHER EXPECTED FRIDAY AND
SATURDAY WITH PRECIP CHANCES RETURNING LATE IN THE WEEKEND AS
SYSTEM APPROACHES FROM THE SOUTHWESTERN U.S.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 47 29 61 39 / 90 0 0 0
HOBART OK 49 24 63 39 / 50 0 0 0
WICHITA FALLS TX 51 29 63 39 / 10 0 0 0
GAGE OK 45 22 66 41 / 40 0 0 0
PONCA CITY OK 46 24 61 39 / 90 0 0 0
DURANT OK 49 31 60 38 / 30 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...HARD FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR OKZ004>025-
027-033>038-044.
WIND ADVISORY UNTIL NOON CDT TODAY FOR OKZ004>031-033>041-
044>046-050.
WINTER WEATHER ADVISORY UNTIL 11 AM CDT THIS MORNING FOR OKZ004-
005-009-010-014.
FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR OKZ026-028>032-
039>043-045>048-050>052.
TX...HARD FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR TXZ083>089.
WIND ADVISORY UNTIL NOON CDT TODAY FOR TXZ083>090.
FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR TXZ090.
&&
$$
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1039 AM EDT MON APR 14 2014
.SYNOPSIS...
AFTER ANOTHER MILD DAY...A FRONTAL SYSTEM WILL APPROACH THE AREA
TONIGHT...AND PASS THROUGH THE REGION TUESDAY. BELOW NORMAL
TEMPERATURES WILL FOLLOW THE FRONT AND LAST THROUGH MID-
WEEK...WITH A GRADUAL MODERATION TOWARD THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
SATELLITE IMAGERY AND SFC OBS SHOW PLENTY OF MID AND HIGH CLOUDS
STREAMING NE OVER THE AREA...ESPECIALLY WESTERN LOCATIONS.
IT WILL BE ANOTHER VERY MILD DAY...BUT WITH MORE IN THE WAY OF
CLOUDINESS...EXPECT TODAYS HIGHS TO REMAIN BELOW THOSE OF YESTERDAY
IN MOST AREAS.
LATEST RADAR IMAGERY SHOWS BEST RETURNS JUST REACHING THE OHIO/PA
BORDER. A FEW SPRINKLES MAY MAKE IT INTO WRN CWA THIS AFTERNOON
BUT THE BETTER THE CHANCE FOR A STRAY SHOWER OR EVEN A
THUNDERSTORM WILL BE LATER THIS AFTERNOON. THE OPERATIONAL MODELS
ALL SPLASH AROUND A FAIR AMOUNT OF LIGHT QPF THIS AFTERNOON...AND
THE SREF/GEFS EVEN SHOW A DECENT CHANCE OF MEASURABLE
PRECIP...THOUGH THE PROBABILITIES OF MORE THAN ABOUT A TENTH ARE
PRETTY SMALL. THE HIGH RES NMM/ARW AND HRRR ALL KEEP THE BULK OF
THE FCST AREA MAINLY DRY THROUGH AT LEAST 20Z. THEY ALSO AGREE ON
GENERATING A LINE OF CONVECTION WHICH SHOULD BE ENTERING MY
WESTERN ZONES BY AROUND NIGHTFALL. SPC DOES NOT OUTLOOK US FOR
SEVERE AND INSTABILITY WILL BE LIMITED...BUT WITH STRONG WINDS
ALOFT...I WOULDN`T BE SURPRISED TO SEE A FEW THUNDERSTORMS
ACCOMPANIED BY GUSTY WINDS INTO THE EVENING HOURS.
THE TIMING OF THE CONVECTION INDICATED BY THE HIGH RES MODELS
WOULD SUGGEST THAT THE SHOWERS WILL TEND TO RUN OUT OF GAS AS THEY
HEAD EAST AFTER THE SUN GOING DOWN. REGARDLESS WE WILL SEE
OCCASIONAL RAIN AND SHOWERS CONTINUE INTO TUESDAY. THE TIGHT
TEMPERATURE GRADIENT ASSOCIATED WITH THE FRONT MEANS THERE WILL BE
A BIG BUST POTENTIAL FOR THE OVERNIGHT LOW. IF THE FRONT IS
FAST...LOWS OVER THE NW COULD BE MUCH COOLER THAN I CURRENTLY
PORTRAY.
&&
.SHORT TERM /TUESDAY/...
THE FRONT WILL MOVE ACROSS THE AREA TUESDAY...ALONG WITH THE SAME
BIG TEMP BUST POTENTIAL OF TONIGHT. MODEL THERMAL FIELDS SHOW A
VERY TIGHT PACKING OF THE COLD AIR JUST BEHIND THE FRONT SO SMALL
TIMING PROBLEMS WILL MEAN RELATIVELY BIG TEMP SWINGS AS THE SYSTEM
SLIDES EAST.
A COUPLE OF OTHER CONCERNS FOR TUESDAY INCLUDE THE POTENTIAL FOR A
NARROW COLD FRONTAL RAINBAND TO FORM...AS WELL AS HOW MUCH IF ANY
SNOW MANAGES TO ACCUMULATE ON THE COLD AIR SIDE OF THE WAVY COLD
FRONT.
AS THE UPPER TROUGH TAKES ON A NEGATIVE TILT AND SWINGS
THROUGH...WE HAVE SEEN IN THE PAST THESE FRONTS TAKE ON STRONG
ANAFRONT CHARACTERISTICS INCLUDING A NARROW LINE OF CONVECTION AND
LOCALIZED STRONG GUSTY WINDS AS PROGGED 850-500MB WINDS ON THE
ORDER OF 45-60KT MIX DOWN IN SOME OF THE STRONGER CONVECTION.
THEN THE...SNOW...YUK! COLD AIR MOVING INTO THE AREA BEHIND THE
FRONT SHOULD CAUSE RAIN TO MIX WITH/CHANGEOVER TO WET SNOW ACROSS
THE WESTERN AND CENTRAL MOUNTAINS TUESDAY INTO TUESDAY NIGHT. AT
THIS TIME...I AM THINKING THAT THE PRECIP WILL BE WINDING DOWN
RATHER QUICKLY TUESDAY AFTERNOON INTO THE EVENING...MEANING THE
CHANGE- OVER WILL BE OCCURRING DURING THE DAY FOR THE MOST PART
WHICH IS USUALLY VITAL AT THIS TIME OF THE YEAR. STILL CAN`T RULE
OUT A COATING TO A COUPLE OF SLUSHY INCHES OF SNOW...WHICH COULD
RESULT IN HAZARDOUS TRAVEL AND ROAD CONDITIONS. THE BEST CHANCE
FOR A FEW INCHES OF WET SNOW WILL BE OVER THE HIGHEST ELEVATIONS
IN THE WESTERN ALLEGHENIES. NO HEADLINES ARE PLANNED AT THIS
POINT...BUT THE POTENTIAL HAS BEEN ADDRESSED IN OUR HWO.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
GROWING SEASON TECHNICALLY STARTS TUESDAY OVER MY SERN ZONES.
AFTER SOME COORDINATION WITH SURROUNDING OFFICES...HAVE AGREED TO
LEAN AWAY FROM ANY FROST/FREEZE HEADLINES...BUT THE LOWS WILL
LIKELY SUPPORT A FREEZE WATCH/WARNING BEING ISSUED AT SOME POINT
TODAY.
THE LAST OF THE SHOWERS WILL BE LEAVING THE REGION TUESDAY
EVENING LEADING THE WAY TO A FEW FAIR BUT ABNORMALLY CHILLY DAYS
FROM WEDNESDAY INTO THE END OF THE WEEK. RISING HEIGHTS/SW FLOW
ALOFT OVER THE EASTERN US IN RESPONSE TO FCST TROUGHING OVER THE
N-CENTRAL PLAINS SHOULD ALLOW FOR TEMPERATURES TO REBOUND TOWARD
THE WEEKEND.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
BREEZY CONDITIONS AND A DRY AIRMASS KEEPING CONDITIONS
VFR. EXPECT THIS TO BE THE CASE FOR MOST OF THE DAY.
COLD FRONT STILL WELL TO THE WEST...NEAR LAKE MI.
CONVECTION TO THE SOUTH IS THE MAIN PLAYER AT THE CURRENT
TIME...AS THE NORTHERN SECTION OF THE FRONT IS NOT REAL
ACTIVE AT THIS POINT.
VAD WINDS STILL 35 TO 40 KNOTS. HAVE LLWS IN TAFS.
SHOWERS WILL BECOME MORE WIDESPREAD AFTER SUNSET INTO
TUE. SOME CHC OF THUNDER...BUT MUCH OF THE RAIN WILL BE
ON THE COLD SIDE OF THE FRONT. ALSO DEWPOINTS NOT FCST
TO BE THAT HIGH...AND THE THERMAL RIDGE IS EXPECTED TO
BE EAST OF OUR AREA.
GUSTY NORTH WINDS EXPECTED FROM TUE AFT...INTO WED AM.
VERY STRONG COLD ADVECTION...THUS RAIN WILL LIKELY
CHANGE TO SNOW BEFORE ENDING TUESDAY NIGHT.
WED INTO FRIDAY LOOKS OK AT THIS POINT.
OUTLOOK...
-TUE...RAIN/REDUCED CIGS...ENDING AS A BRIEF PERIOD
OF WET SNOW ACROSS THE NORTHERN AND WESTERN MTNS.
.WED-THU...VFR.
.FRI...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE/GARTNER
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...GARTNER/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
643 AM EDT MON APR 14 2014
.SYNOPSIS...
AFTER ANOTHER MILD DAY...A FRONTAL SYSTEM WILL APPROACH THE AREA
TONIGHT...AND PASS THROUGH THE REGION TUESDAY. BELOW NORMAL
TEMPERATURES WILL FOLLOW THE FRONT AND LAST THROUGH MID-
WEEK...WITH A GRADUAL MODERATION TOWARD THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
SATELLITE SHOWS PLENTY OF MID AND HIGH CLOUDS STREAMING NE OVER
THE AREA...ESPECIALLY WESTERN LOCATIONS.
IT WILL BE ANOTHER VERY MILD DAY...BUT WITH MORE IN THE WAY OF
CLOUDINESS...WE SHOULD KNOCK A FEW DEGREES OFF YESTERDAY`S HIGHS
IN MOST AREAS.
THE DEEPER WE GET INTO THE DAY THE BETTER THE CHANCE WILL BE FOR
A STRAY SHOWER OR EVEN A THUNDERSTORM. THE OPERATIONAL MODELS ALL
SPLASH AROUND A FAIR AMOUNT OF LIGHT QPF THIS AFTERNOON...AND THE
SREF/GEFS EVEN SHOW A DECENT CHANCE OF MEASURABLEPRECIP...THOUGH
THE PROBABILITIES OF MORE THAN ABOUT A TENTH ARE PRETTY SMALL. THE
HIGH RES NMM/ARW AND HRRR ALL KEEP THE BULK OF THE FCST AREA
MAINLY DRY THROUGH AT LEAST 20Z. THEY ALSO AGREE ON GENERATING A
LINE OF CONVECTION WHICH SHOULD BE ENTERING MY WESTERN ZONES BY
AROUND NIGHTFALL. SPC DOES NOT OUTLOOK US FOR SEVERE AND
INSTABILITY WILL BE LIMITED...BUT WITH STRONG WINDS ALOFT...I
WOULDN`T BE SURPRISED TO SEE A FEW THUNDERSTORMS ACCOMPANIED BY
GUSTY WINDS INTO THE EVENING HOURS.
THE TIMING OF THE CONVECTION INDICATED BY THE HIGH RES MODELS
WOULD SUGGEST THAT THE SHOWERS WILL TEND TO RUN OUT OF GAS AS THEY
HEAD EAST AFTER THE SUN GOING DOWN. REGARDLESS WE WILL SEE
OCCASIONALRAIN AND SHOWERS CONTINUE INTO TUESDAY. THE TIGHT
TEMPERATURE GRADIENT ASSOCIATED WITH THE FRONT MEANS THERE WILL BE
A BIG BUST POTENTIAL FOR THE OVERNIGHT LOW. IF THE FRONT IS
FAST...LOWS OVER THE NW COULD BE MUCH COOLER THAN I CURRENTLY
PORTRAY.
&&
.SHORT TERM /TUESDAY/...
THE FRONT WILL MOVE ACROSS THE AREA TUESDAY...ALONG WITH THE SAME
BIG TEMP BUST POTENTIAL OF TONIGHT. MODEL THERMAL FIELDS SHOW A
VERY TIGHT PACKING OF THE COLD AIR JUST BEHIND THE FRONT SO SMALL
TIMING PROBLEMS WILL MEAN RELATIVELY BIG TEMP SWINGS AS THE SYSTEM
SLIDES EAST.
A COUPLE OF OTHER CONCERNS FOR TUESDAY INCLUDE THE POTENTIAL FOR A
NARROW COLD FRONTAL RAINBAND TO FORM...AS WELL AS HOW MUCH IF ANY
SNOW MANAGES TO ACCUMULATE ON THE COLD AIR SIDE OF THE WAVY COLD
FRONT.
AS THE UPPER TROUGH TAKES ON A NEGATIVE TILT AND SWINGS
THROUGH...WE HAVE SEEN IN THE PAST THESE FRONTS TAKE ON STRONG
ANAFRONT CHARACTERISTICS INCLUDING A NARROW LINE OF CONVECTION AND
LOCALIZED STRONG GUSTY WINDS AS PROGGED 850-500MB WINDS ON THE
ORDER OF 45-60KT MIX DOWN IN SOME OF THE STRONGER CONVECTION.
THEN THE...SNOW...YUK! COLD AIR MOVING INTO THE AREA BEHIND THE
FRONT SHOULD CAUSE RAIN TO MIX WITH/CHANGEOVER TO WET SNOW ACROSS
THE WESTERN AND CENTRAL MOUNTAINS TUESDAY INTO TUESDAY NIGHT. AT
THIS TIME...I AM THINKING THAT THE PRECIP WILL BE WINDING DOWN
RATHER QUICKLY TUESDAY AFTERNOON INTO THE EVENING...MEANING THE
CHANGE- OVER WILL BE OCCURRING DURING THE DAY FOR THE MOST PART
WHICH IS USUALLY VITAL AT THIS TIME OF THE YEAR. STILL CAN`T RULE
OUT A COATING TO A COUPLE OF SLUSHY INCHES OF SNOW...WHICH COULD
RESULT IN HAZARDOUS TRAVEL AND ROAD CONDITIONS. THE BEST CHANCE
FOR A FEW INCHES OF WET SNOW WILL BE OVER THE HIGHEST ELEVATIONS
IN THE WESTERN ALLEGHENIES. NO HEADLINES ARE PLANNED AT THIS
POINT...BUT THE POTENTIAL HAS BEEN ADDRESSED IN OUR HWO.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
GROWING SEASON TECHNICALLY STARTS TUESDAY OVER MY SERN ZONES.
AFTER SOME COORDINATION WITH SURROUNDING OFFICES...HAVE AGREED TO
LEAN AWAY FROM ANY FROST/FREEZE HEADLINES...BUT THE LOWS WILL
LIKELY SUPPORT A FREEZE WATCH/WARNING BEING ISSUED AT SOME POINT
TODAY.
THE LAST OF THE SHOWERS WILL BE LEAVING THE REGION TUESDAY
EVENING LEADING THE WAY TO A FEW FAIR BUT ABNORMALLY CHILLY DAYS
FROM WEDNESDAY INTO THE END OF THE WEEK. RISING HEIGHTS/SW FLOW
ALOFT OVER THE EASTERN US IN RESPONSE TO FCST TROUGHING OVER THE
N-CENTRAL PLAINS SHOULD ALLOW FOR TEMPERATURES TO REBOUND TOWARD
THE WEEKEND.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
BREEZY CONDITIONS AND A DRY AIRMASS KEEPING CONDITIONS
VFR. EXPECT THIS TO BE THE CASE FOR MOST OF THE DAY.
COLD FRONT STILL WELL TO THE WEST...NEAR LAKE MI.
CONVECTION TO THE SOUTH IS THE MAIN PLAYER AT THE CURRENT
TIME...AS THE NORTHERN SECTION OF THE FRONT IS NOT REAL
ACTIVE AT THIS POINT.
VAD WINDS STILL 35 TO 40 KNOTS. HAVE LLWS IN TAFS.
SHOWERS WILL BECOME MORE WIDESPREAD AFTER SUNSET INTO
TUE. SOME CHC OF THUNDER...BUT MUCH OF THE RAIN WILL BE
ON THE COLD SIDE OF THE FRONT. ALSO DEWPOINTS NOT FCST
TO BE THAT HIGH...AND THE THERMAL RIDGE IS EXPECTED TO
BE EAST OF OUR AREA.
GUSTY NORTH WINDS EXPECTED FROM TUE AFT...INTO WED AM.
VERY STRONG COLD ADVECTION...THUS RAIN WILL LIKELY
CHANGE TO SNOW BEFORE ENDING TUESDAY NIGHT.
WED INTO FRIDAY LOKKS OK AT THIS POINT.
OUTLOOK...
-TUE...RAIN/REDUCED CIGS...ENDING AS A BRIEF PERIOD
OF WET SNOW ACROSS THE NORTHERN AND WESTERN MTNS.
.WED-THU...VFR.
.FRI...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
940 AM CDT MON APR 14 2014
.MESOSCALE UPDATE...MOST OF THE EARLIER SHOWERS HAVE EXITED MIDDLE
TENNESSEE, WITH A DRY WEDGE NOW BUILDING IN THAT WILL KEEP US
ESSENTIALLY RAIN-FREE FOR THE NEXT FEW HOURS. THE 14Z LAPS SOUNDING
FOR BNA SHOWS VERY LITTLE INSTABILITY IN PLACE, WITH A CAPPING
INVERSION ABOVE 900 MB. THE LATEST SURFACE MAP SHOWS A SURFACE
COLD FRONT SITUATED JUST WEST OF PAH, WITH THE FRONT PUSHING
THROUGH MIDDLE TENNESSEE DURING THE LATE AFTERNOON AND EVENING.
MODEL SOUNDINGS DO SHOW THE AFOREMENTIONED CAP ERODING JUST AHEAD
OF THE FRONT, WITH MUCH DEEPER INSTABILITY AND THUNDERSTORMS
LIKELY DEVELOPING WITH THE FRONT. LIKEWISE, THE HRRR DOES SHOW
MORE WIDESPREAD ACTIVITY DEVELOPING DURING THE AFTERNOON, SO THE
CURRENT FORECAST APPEARS TO BE ON TARGET. SPC CONTINUES TO SHOW
GENERAL THUNDERSTORMS FOR US, WITH A SLIGHT RISK AREA TO OUR
SOUTH.
&&
.PREV DISCUSSION... /ISSUED 710 AM CDT MON APR 14 2014/
UPDATE...
PER CURRENT REGIONAL RADAR MOSAIC IMAGERY AND SHORT RANGE
MODELS... LOOKS LIKE MAIN SWATH OF SHWRS/SCT TSTMS WILL MOVE E OF
MID STATE OVER THE NEXT COUPLE OF HOURS...WITH GENERALLY A BREAK
IN SHWRS EXPECTED UNTIL LATER THIS AFTERNOON. UPDATED THE SUITE OF
FORECAST PRODUCTS TO MENTION A CHANCE OF SHWRS BEHIND MAIN BAND
JUST IN CASE OF SOME DEVELOPMENT BEFORE THEN.
PREV DISCUSSION.../ISSUED 641 AM CDT MON APR 14 2014/
AVIATION 12Z DISCUSSION...
FRONTAL BOUNDARY TO MOVE ACROSS THE AREA TODAY. REDEVELOPMENT OF
SHOWER AND TSTM ACTIVITY IS POSSIBLE THIS AFTERNOON.
TONIGHT...UPPER LEVEL ENERGY WILL COME INTO PLAY WITHIN THE COLD
SECTOR BEHIND THE FROPA. THIS WILL RESULT IN A CONTINUATION OF
ELEVATED WIND SPEEDS...SHOWER CONDITIONS AND LOW CIGS.
PREV DISCUSSION... /ISSUED 331 AM CDT MON APR 14 2014/
DISCUSSION...
FORECAST REASONING WILL LEAN TOWARD A CONSENSUS MODEL SOLUTION
COMPROMISE FOR THE FORECAST PERIOD UNLESS OTHERWISE NOTED.
FORECAST QUANDARIES...CONVECTION STRENGTH TODAY...WINTRY MIX
POTENTIAL MAINLY NW PORTIONS OF MID STATE LATE TONIGHT...WIND
ADVISORY TODAY THRU TUE/FREEZE WATCH POTENTIAL WED MORNING...
AND TEMPS.
A LOT OF QUANDARIES FOR THIS FORECAST PERIOD. STARTING OFF...
EXPECTING THIS INITIAL ROUND OF SHWRS/TSTMS TO MOVE THRU THE MID
STATE THRU THE REMAINDER OF THE EARLY MORNING HRS...WITH ADDITIONAL
REDEVELOPMENT EXPECTED AT LEAST BY THIS AFTERNOON AS SFC FRONT
APPROACHES CKV AROUND 18Z AND MOVES TO JUST EAST OF NASHVILLE BY
00Z. SOME STRONG TSTMS WILL CONTINUE TO BE POSSIBLE TODAY JUST
AHEAD OF THE FRONTAL PASSAGE AND ACROSS SRN PORTIONS OF THE MID
STATE WHERE INSTABILITY AND FORCING WILL BE THE GREATEST. WILL GO
CLOSE TO MOS VALUES FOR TEMPS TODAY WITH HIGHS IN THE UPPER 60S TO
LOWER 70S. FRONT SHOULD PUSH E OF PLATEAU BY 15/06Z...WITH SOME
LINGERING MOISTURE BEHIND FRONTAL PASSAGE AHEAD OF THE UPPER LEVEL
TROUGH. THERE IS SOME POTENTIAL FOR A WINTRY MIX LATE ACROSS NW
PORTIONS OF THE MID STATE AS COLDER AIR WORKS IN...WITH TEMPS IN
THE MID 30S ACROSS THIS PORTION OF THE MID STATE...BUT UPPER 30S TO
LOWER 40S ELSEWHERE...BUT WITH MOISTURE PULLING OUT OF THIS REGION
RATHER QUICKLY AFTER 15/06Z...DO NOT FEEL AT THIS TIME CONFIDENT
ENOUGH TO MENTION...AND BELIEVE ANOTHER SET OF MODEL RUNS IS
NEEDED FOR FURTHER CLARIFICATION. EXPECTING TEMPS TO MAINLY BE IN
THE UPPER 40S ON TUE WITH BREEZY CONDITIONS CONTINUING. AS RIDGING
INFLUENCES BECOME EVEN MORE ENHANCED ACROSS THE MID STATE ON TUE
NIGHT...SKIES CLEAR...AND WINDS BECOME LIGHT...TEMPS SHOULD DROP
INTO THE MID TO UPPER 20S.
THUS...WITH THE ABOVE IN MIND...AND WITH THE SURFACE PRESSURE
GRADIENT CONTINUING TO BE STRONG THROUGH 15/00Z...AND INCREASING
EVEN MORE AFTER FRONTAL PASSAGE FROM 15/00Z-15/18Z...AND THEN
SLIGHTLY WEAKENING FROM 15/18Z-16/00Z...AND TO NOT CAUSE CONFUSION
BETWEEN SPS PRODUCT THAT NEEDS TO BE UPDATED...WILL BE ISSUING A
WIND ADVISORY THRU 16/00Z WITH BREEZY CONDITIONS WITH SUSTAINED
SOUTHERLY WINDS OF 15 TO 25 MPH WITH GUSTS TO 35 MPH POSSIBLE
THRU 15/00Z...SUSTAINED NORTH WINDS OF 20 TO 30 MPH WITH GUSTS
40-45 MPH 15/00Z-15/18Z...AND GUSTS BACK TO 35 MPH BETWEEN
15/18Z-16/00Z WITH SUSTAINED WINDS OF 15 TO 25 MPH.
THUS...AGAIN...WITH THE ABOVE IN MIND ALSO...AND WITH EXPECTED
TEMPS MAINLY BELOW 27 DEGREES...A HARD FREEZE IS BECOMING MORE
AND MORE LIKELY TO OCCUR BY WED MORNING...AND THUS WILL BE ISSUING
A FREEZE WATCH FROM MIDNIGHT UNTIL 9 AM CDT ON WED MORNING.
WILL BE GOING CLOSE TO PREVIOUS FORECAST REASONING REMAINDER OF WED
THRU THE WEEKEND WITH THE NEXT FRONTAL SYSTEM TO MOVE INTO THE MID
STATE FRI INTO FRI NIGHT...WITH TEMPS AGAIN APPROACHING SEASONABLE
NORMAL VALUES BY WEEKENDS END.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING
FOR TNZ005>011-023>034-056>066-075-077>080-093>095.
WIND ADVISORY UNTIL 7 PM CDT TUESDAY FOR TNZ005>011-023>034-
056>066-075-077>080-093>095.
&&
$$
ROSE
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1041 AM CDT MON APR 14 2014
.UPDATE...
GRIDS HAVE BEEN UPDATED TO INCLUDE SEVERE THUNDERSTORM WATCH 80
FOR AREAS GENERALLY ALONG AND SOUTHEAST OF A LINE FROM KILLEEN TO
ATHENS. STORMS CONTINUE TO DEVELOP IN THESE AREAS WITH
ELEVATED CORES OCCASIONALLY PRODUCING QUARTER SIZED HAIL.
THUNDERSTORMS WILL GRADUALLY SHIFT EAST OF NORTH TEXAS ALONG WITH
THE 850MB FRONT AND THE PRIMARY UPPER TROUGH AXIS. THE WATCH IS IN
EFFECT UNTIL 5 PM CDT...BUT WE SHOULD BE ABLE TO CLEAR COUNTIES FROM
WEST TO EAST AS WARRANTED BY TRENDS.
30
&&
.AVIATION...
/12Z TAFS/
MVFR CONDITIONS WILL PREVAIL THROUGH THE MORNING WITH GUSTY NORTH
WINDS EXPECTED MOST OF THE DAY. EXTENSIVE CLOUDINESS WILL BEGIN TO
SCATTER OUT THIS AFTERNOON AS DRIER AIR MIXES DOWN. VFR CONDITIONS
EXPECTED LATER TODAY THROUGH TUESDAY. WINDS WILL DIMINISH THIS
EVENING BECOMING LGT/VAR BY EARLY TUESDAY...THEN SOUTHERLY AROUND
10KTS TUESDAY AFTERNOON.
DUNN
&&
.PREV UPDATE...
.UPDATE...
ELEVATED CONVECTION NEAR WAXAHACHIE...HILLSBORO...CORSICANA AND
SURROUNDING AREAS WILL CONTINUE TO LIFT NORTHEAST AS AN UPPER
TROUGH DIGS SOUTHEAST ACROSS THE CENTRAL AND SOUTHERN PLAINS. WE
DID A QUICK UPDATE TO INCLUDE POPS THIS MORNING FOR AREAS
IMMEDIATELY EAST AND SOUTH OF DALLAS. ACTIVITY WILL SHIFT EAST OF
THE AREA BY EARLY AFTERNOON ALONG WITH THE TROUGH AXIS. OTHERWISE
STRONG NORTH WINDS WILL CONTINUE THROUGH THE AFTERNOON. CLOUDS AND
COLD ADVECTION WILL KEEP A LID ON TEMPERATURES...WILL KEEP AN EYE
ON TRENDS TO SEE IF AFTERNOON HIGHS NEED TO BE LOWERED AT ALL.
RECORD LOW MAX AT DFW IS 55 FOR TODAY...AND 56 AT WACO SO IT WILL
BE CLOSE.
30
&&
.PREV DISCUSSION... /ISSUED 417 AM CDT MON APR 14 2014/
08Z SURFACE ANALYSIS INDICATED A STRONG COLD FRONT MOVING
SOUTHEAST ACROSS THE CWA...LOCATED NEAR A LINE FROM ATHENS TO
WACO TO LAMPASAS. JUST TO THE NORTHWEST OF THIS FRONT...A LINE OF
SCATTERED SHOWERS AND THUNDERSTORMS WAS OBSERVED...LIKELY
ASSOCIATED WITH THE 850 MB REFLECTION OF THE COLD FRONT. AT
0830Z...NONE OF THIS ACTIVITY WAS STRONG IN NATURE...AND AS
ALLUDED TO ABOVE...IT IS ALL ELEVATED IN NATURE OVER THE FRONTAL
INVERSION. REGIONAL SURFACE OBSERVATIONS INDICATE UNSEASONABLY
COLD AIR BEHIND THE FRONT...WITH TEMPERATURES IN THE LOWER 40S
LOCATED OVER WICHITA FALLS. NORTH WINDS WERE ALREADY RELATIVELY
STRONG BEHIND THE FRONT...WITH MANY LOCATIONS OBSERVING WINDS IN
THE 20 TO 25 MPH RANGE EARLY THIS MORNING.
THIS MORNING...WENT AHEAD AND CANCELLED THE SEVERE THUNDERSTORM
WATCH IN COORDINATION WITH THE SPC AND WFO SHV AS THE COLD FRONT
HAD UNDERCUT ALL ONGOING CONVECTION. THIS DOES NOT MEAN IT/S
IMPOSSIBLE TO GET STRONG STORMS THIS MORNING...HOWEVER THE ONLY
STRONG TO MARGINALLY SEVERE STORM HAZARD ASSOCIATED WITH ELEVATED
STORMS IS GOING TO BE IN THE FORM OF HAIL. RAP FORECAST SOUNDINGS
INDICATE THE PRESENCE OF 1000-1500 J/KG OF MUCAPE AVAILABLE FOR
THESE ELEVATED STORMS. DEEP LAYER SHEAR VALUES LOOK
IMPRESSIVE...BUT ARE NOT REALLY RELEVANT FOR THIS ACTIVITY AS THE
BULK OF THE CONTRIBUTION TO THE HIGHER SHEAR VALUES OCCURS BELOW
THE FRONTAL INVERSION. DEEP LAYER BULK SHEAR CALCULATIONS INDICATE
ABOUT 60 KTS OF SHEAR...WHILE EFFECTIVE BULK SHEAR IS MORE
REALISTICALLY AROUND 25 KTS. AS A RESULT...STRONG...BUT LIKELY
UNORGANIZED ELEVATED CONVECTION IS POSSIBLE THIS MORNING. BASED ON
THE RADAR PRESENTATION OF STORMS SO FAR EARLY THIS
MORNING...CHANCES ARE NO LARGE HAIL WILL FALL ACROSS THE
CWA...HOWEVER IF IT DOES OCCUR...HAIL WILL LIKELY BE CLOSE TO 1
INCH OR QUARTER SIZE IN DIAMETER.
REMAINDER OF TODAY...THE 850 MB FRONT WILL SLIDE SOUTHEAST OF THE
CWA BY LATE THIS MORNING...TAKING ALL THUNDERSTORM CHANCES
SOUTHEAST OUT OF THE AREA IN ITS WAKE. RELATIVELY STRONG ISENTROPIC
DOWNGLIDE/COLD AIR ADVECTION WILL DOMINATE THE LOWER TROPOSPHERE
IN THE WAKE OF THIS FRONT. A STRONG UPPER LEVEL LOW PRESSURE
SYSTEM WILL MOVE FROM WEST TO EAST OVER THE SOUTH PLAINS
TODAY...WHICH WILL SPREAD SOME STRONG LARGE SCALE FORCING FOR
ASCENT OVER THE CWA THIS AFTERNOON. HOWEVER...THE LARGE SCALE
FORCING FOR ASCENT ASSOCIATED WITH THIS UPPER LOW IS NOT EXPECTED
TO PENETRATE MUCH DEEPER THAN THE MIDDLE TROPOSPHERE TODAY BECAUSE
THE MIDDLE TO LOW TROPOSPHERE WILL BE DEFINED BY HIGH STATIC
STABILITY. A THERMODYNAMICALLY STABLE LAYER RESISTS VERTICAL
MOTIONS...AND THEREFORE SHOULD PREVENT ANY ADDITIONAL
PRECIPITATION FROM DEVELOPING OVER THE CWA TODAY ASSOCIATED WITH
THIS UPPER LOW. THIS IS SUCH A STRONG UPPER TROUGH THAT IT WOULD
BE A HUGE SURPRISE TO SEE SOME WEAK RADAR RETURNS DEVELOP OVER THE
CWA EARLY THIS AFTERNOON...BUT THE COLD FRONT PUSHING THROUGH THE
AREA JUST LOOKS TOO STRONG AND COLD TO ALLOW FOR MUCH LIFT TO
OCCUR WHERE WE WOULD NEED IT TO GET RAIN SHOWERS...THAT BEING THE
MID TO LOWER TROPOSPHERE.
ASIDE FROM PRECIPITATION CONCERNS...BEHIND THE FRONT WE SHOULD
JUST SEE STRONG NORTH WINDS AND COLD AIR ADVECTION THROUGHOUT THE
DAY TODAY. TEMPERATURES ARE EXPECTED TO INCREASE INTO THE LOWER TO
MID 50S BY LATE THIS AFTERNOON DESPITE THE STRONG COLD AIR
ADVECTION AS SKIES CLEAR OUT RAPIDLY BEHIND THE PASSAGE OF THE
UPPER TROUGH. EVEN THOUGH THE AIR BEHIND THE FRONT WILL REMAIN
COLD...THE SUN ANGLE IS GETTING TOO HIGH FOR US NOT TO HEAT UP A
BIT EVEN WITH JUST A FEW HOURS OF SUNSHINE. A WIND ADVISORY
REMAINS IN EFFECT FOR THE ENTIRE AREA TODAY DUE TO NORTH WINDS OF
25 TO 30 MPH BEHIND THE FRONT. WINDS SHOULD DIMINISH AN HOUR OR
TWO AFTER SUNSET AS HIGH PRESSURE BEGINS TO MOVE INTO THE REGION.
TONIGHT...HIGH PRESSURE IS EXPECTED TO SLIDE SOUTH-SOUTHEAST
ACROSS TEXAS FROM THE TX PANHANDLE TONIGHT. THIS WILL RESULT IN
NEARLY CALM WINDS ACROSS WEST CENTRAL TEXAS...AND LIGHT NORTHERLY
WINDS TO THE EAST. LIGHT WINDS AND CLEAR SKIES WILL MAKE FOR AN
IDEAL RADIATIONAL COOLING ENVIRONMENT RESULTING IN TEMPERATURES
FALLING INTO THE UPPER 20S TO MID 30S ACROSS THE CWA. YES...YOU
READ THAT CORRECTLY...PARTS OF NORTH AND CENTRAL TEXAS ARE
EXPECTED TO FALL BELOW FREEZING TONIGHT INTO TUESDAY MORNING. THIS
IS PUSHING RECORD TERRITORY FOR A LATE FREEZE WHICH IS QUITE
REMARKABLE CONSIDERING RECORDS HAVE BEEN KEPT SINCE THE LATE 1800S
TO EARLY 1900S...SO WE ARE LOOKING AT AN EVENT THAT HAS A RETURN
INTERVAL OF OVER 100 YEARS...FOR NORTH AND CENTRAL TEXAS AT LEAST.
AS A RESULT...THIS FREEZE...ASSUMING IT OCCURS AS FORECAST...HAS
THE POTENTIAL TO DO QUITE A BIT OF DAMAGE TO OUTDOOR PLANTS AS
MOST FOLKS WOULD NOT HAVE WAITED THIS LONG TO GET THEIR SPRING
PLANTING TAKEN CARE OF. AT ANY RATE...THIS IS WHY FREEZE WARNINGS
ARE ISSUED...TO GIVE FOLKS A CHANCE TO PROTECT THEIR PLANTS.
A FREEZE WARNING IS IN EFFECT FROM 1 AM TO 10 AM TONIGHT/TUESDAY
MORNING FOR LOCATIONS ALONG AND NORTHWEST OF A LINE FROM SULPHUR
SPRINGS TO KELLER TO WACO TO LAMPASAS. LOCATIONS JUST SOUTHEAST OF
THIS LINE GENERALLY HAVE FORECAST LOWS AT 33 DEGREES...SO THIS
WARNING MAY BE EXPANDED BASED ON HOW WARM WE GET THIS AFTERNOON
AND BASED ON NEW MODEL GUIDANCE THROUGHOUT THE DAY.
FORTUNATELY...MOST LOCATIONS IN THE FREEZE WARNING SHOULD SEE LOWS
FALL JUST BELOW FREEZING...GENERALLY 30 TO 32 DEGREES.
TEMPERATURES FALLING INTO THE UPPER 20S IS MORE LIKELY NORTH OF
INTERSTATE 30...NEAR THE RED RIVER.
TEMPERATURES ARE MORE LIKELY TO FALL BELOW FREEZING IN RURAL AREAS
MORE SO THAN URBAN AREAS. THE URBAN HEAT ISLAND EFFECT WILL KEEP
MOST OF THE CONCRETED AREAS OF THE METROPLEX ABOVE FREEZING.
TARRANT COUNTY IS INCLUDED IN THE FREEZE WARNING ANYWAYS BECAUSE
THE FAR NORTH AND WESTERN PORTIONS OF THE COUNTY...OUTSIDE OF THE
820 LOOP...ARE MORE LIKELY TO SEE FREEZING TEMPERATURES.
TEMPERATURES ARE EXPECTED TO CLIMB ABOVE FREEZING AREA WIDE AFTER
10 AM TUESDAY MORNING.
FROST IS POSSIBLE IN AREAS NOT INCLUDED IN THE FREEZE WARNING...SO
EVEN IF YOU ARE NOT IN THE FREEZE WARNING AT THIS TIME...IT MAY BE
PRUDENT TO PROTECT YOUR PLANTS ANYWAYS AS A PRECAUTION. THE AIR IS
EXPECTED TO BE VERY DRY...SO WIDESPREAD FROST IS NOT LIKELY...BUT
IT MAY BE BETTER TO BE SAFE THAN SORRY.
REMAINDER OF THE FORECAST...WE WILL WARM UP AFTER TUESDAY...WITH
NO MORE POTENTIAL FROSTS OR FREEZES IN THE FORECAST THROUGH NEXT
WEEKEND. TUESDAY NIGHTS LOWS WILL BE WELL BELOW NORMAL AGAIN...BUT
SHOULD FALL INTO THE MID TO UPPER 30S AT WORST. BY
WEDNESDAY...SOUTH WINDS WILL HELP BRING DEW POINTS BACK UP INTO
THE MID TO UPPER 40S...BRINGING ABOUT A RETURN TO MORE SEASONAL
TEMPERATURES DURING THE DAYTIME AND OVERNIGHT.
OUR NEXT CHANCE OF RAIN STILL LOOKS TO BE THURSDAY...ASSOCIATED
WITH AN UPPER LEVEL TROUGH PROGGED TO MOVE OVER THE SOUTHERN
PLAINS THURSDAY AFTERNOON. HOWEVER...THE ECMWF AND GFS BOTH KEEP
THE BULK OF THE UPPER LEVEL FORCING FOR ASCENT ASSOCIATED WITH
THIS TROUGH NORTH OF THE CWA. ASSUMING THIS VERIFIES...THIS DOES
NOT USUALLY BODE WELL FOR PRECIPITATION CHANCES...EVEN WITH A WEAK
COLD FRONT PUSHING SOUTHEAST ACROSS THE CWA THURSDAY
AFTERNOON/EVENING. THE LOSS OF UPPER LEVEL DYNAMICS USUALLY MAKES
PRECIPITATION ALONG COLD FRONTS ISOLATED AT BEST. THE CANADIAN IS
FURTHER SOUTH WITH THIS UPPER TROUGH...AND THEREFORE HAS MUCH MORE
PRECIPITATION FOR THE CWA. WILL CONTINUE TO MONITOR THE EVOLUTION
OF THIS TROUGH IN FUTURE FORECASTS...HOWEVER FOR NOW JUST KEPT
POPS IN THE 20 TO 30 PERCENT RANGE IN LINE WITH THE GFS/ECMWF
SOLUTION.
AFTER THURSDAY...OUR NEXT SHOT AT RAIN LOOKS TO BE SATURDAY NIGHT
INTO SUNDAY...AS ALL GUIDANCE INDICATES AN UPPER LEVEL TROUGH WILL
MOVE OVER THE SOUTHWESTERN CONUS AND TOWARDS NORTH TX AT THAT
TIME. THE GFS IS THE MOST AGGRESSIVE WITH TAPPING INTO SOME
TROPICAL PACIFIC MOISTURE IN THE UPPER TROPOSPHERE COURTESY OF THE
SUB-TROPICAL JET. AS A RESULT THE GFS GIVES THE CWA A
GOOD...WIDESPREAD ONE HALF TO ONE INCH OF RAINFALL FROM SATURDAY
NIGHT THROUGH SUNDAY. WILL NOT BITE OFF ON THIS SOLUTION QUITE
YET...BUT IT IS A GOOD SIGN THAT AT LEAST ALL MODELS HAVE SOME
VERSION OF THIS TROUGH OVER THE SOUTHWESTERN CONUS. IF THIS
CONSISTENT CONTINUES...POPS WILL BE INCREASED AREA WIDE FOR
SATURDAY NIGHT INTO SUNDAY. THIS DOES NOT LOOK TO BE A GOOD SEVERE
WEATHER SET UP FOR NOW...SO A GOOD WIDESPREAD RAINFALL WITH
EMBEDDED THUNDERSTORMS IS WHAT IS EXPECTED AT THIS TIME. WE WILL
SEE HOW THINGS CHANGE AS WE GET CLOSER TO NEXT WEEKEND OF COURSE.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 55 34 63 42 66 / 10 5 0 0 0
WACO, TX 56 33 63 36 67 / 30 0 0 0 0
PARIS, TX 51 30 59 36 64 / 20 5 0 0 0
DENTON, TX 53 29 62 38 66 / 10 5 0 0 0
MCKINNEY, TX 53 30 62 38 65 / 10 5 0 0 0
DALLAS, TX 56 35 63 42 66 / 10 5 0 0 0
TERRELL, TX 55 33 62 37 65 / 20 5 0 0 0
CORSICANA, TX 54 33 61 38 66 / 30 5 0 0 0
TEMPLE, TX 58 33 64 36 68 / 30 0 0 0 0
MINERAL WELLS, TX 55 32 63 37 69 / 10 0 0 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 1 AM TO 10 AM CDT TUESDAY FOR TXZ091>095-
100>107-115>118-129>133-141>145-156-157-159.
WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR TXZ091>095-100>107-
115>123-129>135-141>148-156>162-174-175.
&&
$$
58/30
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
842 AM CDT MON APR 14 2014
.UPDATE...
ELEVATED CONVECTION NEAR WAXAHACHIE...HILLSBORO...CORSICANA AND
SURROUNDING AREAS WILL CONTINUE TO LIFT NORTHEAST AS AN UPPER
TROUGH DIGS SOUTHEAST ACROSS THE CENTRAL AND SOUTHERN PLAINS. WE
DID A QUICK UPDATE TO INCLUDE POPS THIS MORNING FOR AREAS
IMMEDIATELY EAST AND SOUTH OF DALLAS. ACTIVITY WILL SHIFT EAST OF
THE AREA BY EARLY AFTERNOON ALONG WITH THE TROUGH AXIS. OTHERWISE
STRONG NORTH WINDS WILL CONTINUE THROUGH THE AFTERNOON. CLOUDS AND
COLD ADVECTION WILL KEEP A LID ON TEMPERATURES...WILL KEEP AN EYE
ON TRENDS TO SEE IF AFTERNOON HIGHS NEED TO BE LOWERED AT ALL.
RECORD LOW MAX AT DFW IS 55 FOR TODAY...AND 56 AT WACO SO IT WILL
BE CLOSE.
30
&&
.AVIATION...
/12Z TAFS/
MVFR CONDITIONS WILL PREVAIL THROUGH THE MORNING WITH GUSTY NORTH
WINDS EXPECTED MOST OF THE DAY. EXTENSIVE CLOUDINESS WILL BEGIN TO
SCATTER OUT THIS AFTERNOON AS DRIER AIR MIXES DOWN. VFR CONDITIONS
EXPECTED LATER TODAY THROUGH TUESDAY. WINDS WILL DIMINISH THIS
EVENING BECOMING LGT/VAR BY EARLY TUESDAY...THEN SOUTHERLY AROUND
10KTS TUESDAY AFTERNOON.
DUNN
&&
.PREV DISCUSSION... /ISSUED 417 AM CDT MON APR 14 2014/
08Z SURFACE ANALYSIS INDICATED A STRONG COLD FRONT MOVING
SOUTHEAST ACROSS THE CWA...LOCATED NEAR A LINE FROM ATHENS TO
WACO TO LAMPASAS. JUST TO THE NORTHWEST OF THIS FRONT...A LINE OF
SCATTERED SHOWERS AND THUNDERSTORMS WAS OBSERVED...LIKELY
ASSOCIATED WITH THE 850 MB REFLECTION OF THE COLD FRONT. AT
0830Z...NONE OF THIS ACTIVITY WAS STRONG IN NATURE...AND AS
ALLUDED TO ABOVE...IT IS ALL ELEVATED IN NATURE OVER THE FRONTAL
INVERSION. REGIONAL SURFACE OBSERVATIONS INDICATE UNSEASONABLY
COLD AIR BEHIND THE FRONT...WITH TEMPERATURES IN THE LOWER 40S
LOCATED OVER WICHITA FALLS. NORTH WINDS WERE ALREADY RELATIVELY
STRONG BEHIND THE FRONT...WITH MANY LOCATIONS OBSERVING WINDS IN
THE 20 TO 25 MPH RANGE EARLY THIS MORNING.
THIS MORNING...WENT AHEAD AND CANCELLED THE SEVERE THUNDERSTORM
WATCH IN COORDINATION WITH THE SPC AND WFO SHV AS THE COLD FRONT
HAD UNDERCUT ALL ONGOING CONVECTION. THIS DOES NOT MEAN IT/S
IMPOSSIBLE TO GET STRONG STORMS THIS MORNING...HOWEVER THE ONLY
STRONG TO MARGINALLY SEVERE STORM HAZARD ASSOCIATED WITH ELEVATED
STORMS IS GOING TO BE IN THE FORM OF HAIL. RAP FORECAST SOUNDINGS
INDICATE THE PRESENCE OF 1000-1500 J/KG OF MUCAPE AVAILABLE FOR
THESE ELEVATED STORMS. DEEP LAYER SHEAR VALUES LOOK
IMPRESSIVE...BUT ARE NOT REALLY RELEVANT FOR THIS ACTIVITY AS THE
BULK OF THE CONTRIBUTION TO THE HIGHER SHEAR VALUES OCCURS BELOW
THE FRONTAL INVERSION. DEEP LAYER BULK SHEAR CALCULATIONS INDICATE
ABOUT 60 KTS OF SHEAR...WHILE EFFECTIVE BULK SHEAR IS MORE
REALISTICALLY AROUND 25 KTS. AS A RESULT...STRONG...BUT LIKELY
UNORGANIZED ELEVATED CONVECTION IS POSSIBLE THIS MORNING. BASED ON
THE RADAR PRESENTATION OF STORMS SO FAR EARLY THIS
MORNING...CHANCES ARE NO LARGE HAIL WILL FALL ACROSS THE
CWA...HOWEVER IF IT DOES OCCUR...HAIL WILL LIKELY BE CLOSE TO 1
INCH OR QUARTER SIZE IN DIAMETER.
REMAINDER OF TODAY...THE 850 MB FRONT WILL SLIDE SOUTHEAST OF THE
CWA BY LATE THIS MORNING...TAKING ALL THUNDERSTORM CHANCES
SOUTHEAST OUT OF THE AREA IN ITS WAKE. RELATIVELY STRONG ISENTROPIC
DOWNGLIDE/COLD AIR ADVECTION WILL DOMINATE THE LOWER TROPOSPHERE
IN THE WAKE OF THIS FRONT. A STRONG UPPER LEVEL LOW PRESSURE
SYSTEM WILL MOVE FROM WEST TO EAST OVER THE SOUTH PLAINS
TODAY...WHICH WILL SPREAD SOME STRONG LARGE SCALE FORCING FOR
ASCENT OVER THE CWA THIS AFTERNOON. HOWEVER...THE LARGE SCALE
FORCING FOR ASCENT ASSOCIATED WITH THIS UPPER LOW IS NOT EXPECTED
TO PENETRATE MUCH DEEPER THAN THE MIDDLE TROPOSPHERE TODAY BECAUSE
THE MIDDLE TO LOW TROPOSPHERE WILL BE DEFINED BY HIGH STATIC
STABILITY. A THERMODYNAMICALLY STABLE LAYER RESISTS VERTICAL
MOTIONS...AND THEREFORE SHOULD PREVENT ANY ADDITIONAL
PRECIPITATION FROM DEVELOPING OVER THE CWA TODAY ASSOCIATED WITH
THIS UPPER LOW. THIS IS SUCH A STRONG UPPER TROUGH THAT IT WOULD
BE A HUGE SURPRISE TO SEE SOME WEAK RADAR RETURNS DEVELOP OVER THE
CWA EARLY THIS AFTERNOON...BUT THE COLD FRONT PUSHING THROUGH THE
AREA JUST LOOKS TOO STRONG AND COLD TO ALLOW FOR MUCH LIFT TO
OCCUR WHERE WE WOULD NEED IT TO GET RAIN SHOWERS...THAT BEING THE
MID TO LOWER TROPOSPHERE.
ASIDE FROM PRECIPITATION CONCERNS...BEHIND THE FRONT WE SHOULD
JUST SEE STRONG NORTH WINDS AND COLD AIR ADVECTION THROUGHOUT THE
DAY TODAY. TEMPERATURES ARE EXPECTED TO INCREASE INTO THE LOWER TO
MID 50S BY LATE THIS AFTERNOON DESPITE THE STRONG COLD AIR
ADVECTION AS SKIES CLEAR OUT RAPIDLY BEHIND THE PASSAGE OF THE
UPPER TROUGH. EVEN THOUGH THE AIR BEHIND THE FRONT WILL REMAIN
COLD...THE SUN ANGLE IS GETTING TOO HIGH FOR US NOT TO HEAT UP A
BIT EVEN WITH JUST A FEW HOURS OF SUNSHINE. A WIND ADVISORY
REMAINS IN EFFECT FOR THE ENTIRE AREA TODAY DUE TO NORTH WINDS OF
25 TO 30 MPH BEHIND THE FRONT. WINDS SHOULD DIMINISH AN HOUR OR
TWO AFTER SUNSET AS HIGH PRESSURE BEGINS TO MOVE INTO THE REGION.
TONIGHT...HIGH PRESSURE IS EXPECTED TO SLIDE SOUTH-SOUTHEAST
ACROSS TEXAS FROM THE TX PANHANDLE TONIGHT. THIS WILL RESULT IN
NEARLY CALM WINDS ACROSS WEST CENTRAL TEXAS...AND LIGHT NORTHERLY
WINDS TO THE EAST. LIGHT WINDS AND CLEAR SKIES WILL MAKE FOR AN
IDEAL RADIATIONAL COOLING ENVIRONMENT RESULTING IN TEMPERATURES
FALLING INTO THE UPPER 20S TO MID 30S ACROSS THE CWA. YES...YOU
READ THAT CORRECTLY...PARTS OF NORTH AND CENTRAL TEXAS ARE
EXPECTED TO FALL BELOW FREEZING TONIGHT INTO TUESDAY MORNING. THIS
IS PUSHING RECORD TERRITORY FOR A LATE FREEZE WHICH IS QUITE
REMARKABLE CONSIDERING RECORDS HAVE BEEN KEPT SINCE THE LATE 1800S
TO EARLY 1900S...SO WE ARE LOOKING AT AN EVENT THAT HAS A RETURN
INTERVAL OF OVER 100 YEARS...FOR NORTH AND CENTRAL TEXAS AT LEAST.
AS A RESULT...THIS FREEZE...ASSUMING IT OCCURS AS FORECAST...HAS
THE POTENTIAL TO DO QUITE A BIT OF DAMAGE TO OUTDOOR PLANTS AS
MOST FOLKS WOULD NOT HAVE WAITED THIS LONG TO GET THEIR SPRING
PLANTING TAKEN CARE OF. AT ANY RATE...THIS IS WHY FREEZE WARNINGS
ARE ISSUED...TO GIVE FOLKS A CHANCE TO PROTECT THEIR PLANTS.
A FREEZE WARNING IS IN EFFECT FROM 1 AM TO 10 AM TONIGHT/TUESDAY
MORNING FOR LOCATIONS ALONG AND NORTHWEST OF A LINE FROM SULPHUR
SPRINGS TO KELLER TO WACO TO LAMPASAS. LOCATIONS JUST SOUTHEAST OF
THIS LINE GENERALLY HAVE FORECAST LOWS AT 33 DEGREES...SO THIS
WARNING MAY BE EXPANDED BASED ON HOW WARM WE GET THIS AFTERNOON
AND BASED ON NEW MODEL GUIDANCE THROUGHOUT THE DAY.
FORTUNATELY...MOST LOCATIONS IN THE FREEZE WARNING SHOULD SEE LOWS
FALL JUST BELOW FREEZING...GENERALLY 30 TO 32 DEGREES.
TEMPERATURES FALLING INTO THE UPPER 20S IS MORE LIKELY NORTH OF
INTERSTATE 30...NEAR THE RED RIVER.
TEMPERATURES ARE MORE LIKELY TO FALL BELOW FREEZING IN RURAL AREAS
MORE SO THAN URBAN AREAS. THE URBAN HEAT ISLAND EFFECT WILL KEEP
MOST OF THE CONCRETED AREAS OF THE METROPLEX ABOVE FREEZING.
TARRANT COUNTY IS INCLUDED IN THE FREEZE WARNING ANYWAYS BECAUSE
THE FAR NORTH AND WESTERN PORTIONS OF THE COUNTY...OUTSIDE OF THE
820 LOOP...ARE MORE LIKELY TO SEE FREEZING TEMPERATURES.
TEMPERATURES ARE EXPECTED TO CLIMB ABOVE FREEZING AREA WIDE AFTER
10 AM TUESDAY MORNING.
FROST IS POSSIBLE IN AREAS NOT INCLUDED IN THE FREEZE WARNING...SO
EVEN IF YOU ARE NOT IN THE FREEZE WARNING AT THIS TIME...IT MAY BE
PRUDENT TO PROTECT YOUR PLANTS ANYWAYS AS A PRECAUTION. THE AIR IS
EXPECTED TO BE VERY DRY...SO WIDESPREAD FROST IS NOT LIKELY...BUT
IT MAY BE BETTER TO BE SAFE THAN SORRY.
REMAINDER OF THE FORECAST...WE WILL WARM UP AFTER TUESDAY...WITH
NO MORE POTENTIAL FROSTS OR FREEZES IN THE FORECAST THROUGH NEXT
WEEKEND. TUESDAY NIGHTS LOWS WILL BE WELL BELOW NORMAL AGAIN...BUT
SHOULD FALL INTO THE MID TO UPPER 30S AT WORST. BY
WEDNESDAY...SOUTH WINDS WILL HELP BRING DEW POINTS BACK UP INTO
THE MID TO UPPER 40S...BRINGING ABOUT A RETURN TO MORE SEASONAL
TEMPERATURES DURING THE DAYTIME AND OVERNIGHT.
OUR NEXT CHANCE OF RAIN STILL LOOKS TO BE THURSDAY...ASSOCIATED
WITH AN UPPER LEVEL TROUGH PROGGED TO MOVE OVER THE SOUTHERN
PLAINS THURSDAY AFTERNOON. HOWEVER...THE ECMWF AND GFS BOTH KEEP
THE BULK OF THE UPPER LEVEL FORCING FOR ASCENT ASSOCIATED WITH
THIS TROUGH NORTH OF THE CWA. ASSUMING THIS VERIFIES...THIS DOES
NOT USUALLY BODE WELL FOR PRECIPITATION CHANCES...EVEN WITH A WEAK
COLD FRONT PUSHING SOUTHEAST ACROSS THE CWA THURSDAY
AFTERNOON/EVENING. THE LOSS OF UPPER LEVEL DYNAMICS USUALLY MAKES
PRECIPITATION ALONG COLD FRONTS ISOLATED AT BEST. THE CANADIAN IS
FURTHER SOUTH WITH THIS UPPER TROUGH...AND THEREFORE HAS MUCH MORE
PRECIPITATION FOR THE CWA. WILL CONTINUE TO MONITOR THE EVOLUTION
OF THIS TROUGH IN FUTURE FORECASTS...HOWEVER FOR NOW JUST KEPT
POPS IN THE 20 TO 30 PERCENT RANGE IN LINE WITH THE GFS/ECMWF
SOLUTION.
AFTER THURSDAY...OUR NEXT SHOT AT RAIN LOOKS TO BE SATURDAY NIGHT
INTO SUNDAY...AS ALL GUIDANCE INDICATES AN UPPER LEVEL TROUGH WILL
MOVE OVER THE SOUTHWESTERN CONUS AND TOWARDS NORTH TX AT THAT
TIME. THE GFS IS THE MOST AGGRESSIVE WITH TAPPING INTO SOME
TROPICAL PACIFIC MOISTURE IN THE UPPER TROPOSPHERE COURTESY OF THE
SUB-TROPICAL JET. AS A RESULT THE GFS GIVES THE CWA A
GOOD...WIDESPREAD ONE HALF TO ONE INCH OF RAINFALL FROM SATURDAY
NIGHT THROUGH SUNDAY. WILL NOT BITE OFF ON THIS SOLUTION QUITE
YET...BUT IT IS A GOOD SIGN THAT AT LEAST ALL MODELS HAVE SOME
VERSION OF THIS TROUGH OVER THE SOUTHWESTERN CONUS. IF THIS
CONSISTENT CONTINUES...POPS WILL BE INCREASED AREA WIDE FOR
SATURDAY NIGHT INTO SUNDAY. THIS DOES NOT LOOK TO BE A GOOD SEVERE
WEATHER SET UP FOR NOW...SO A GOOD WIDESPREAD RAINFALL WITH
EMBEDDED THUNDERSTORMS IS WHAT IS EXPECTED AT THIS TIME. WE WILL
SEE HOW THINGS CHANGE AS WE GET CLOSER TO NEXT WEEKEND OF COURSE.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 55 34 63 42 66 / 10 5 0 0 0
WACO, TX 56 33 63 36 67 / 20 0 0 0 0
PARIS, TX 51 30 59 36 64 / 10 5 0 0 0
DENTON, TX 53 29 62 38 66 / 10 5 0 0 0
MCKINNEY, TX 53 30 62 38 65 / 10 5 0 0 0
DALLAS, TX 56 35 63 42 66 / 10 5 0 0 0
TERRELL, TX 55 33 62 37 65 / 20 5 0 0 0
CORSICANA, TX 54 33 61 38 66 / 30 5 0 0 0
TEMPLE, TX 58 33 64 36 68 / 30 0 0 0 0
MINERAL WELLS, TX 55 32 63 37 69 / 10 0 0 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 1 AM TO 10 AM CDT TUESDAY FOR TXZ091>095-
100>107-115>118-129>133-141>145-156-157-159.
WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR TXZ091>095-100>107-
115>123-129>135-141>148-156>162-174-175.
&&
$$
58/30
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
639 AM CDT MON APR 14 2014
.AVIATION...
/12Z TAFS/
MVFR CONDITIONS WILL PREVAIL THROUGH THE MORNING WITH GUSTY NORTH
WINDS EXPECTED MOST OF THE DAY. EXTENSIVE CLOUDINESS WILL BEGIN TO
SCATTER OUT THIS AFTERNOON AS DRIER AIR MIXES DOWN. VFR CONDITIONS
EXPECTED LATER TODAY THROUGH TUESDAY. WINDS WILL DIMINISH THIS
EVENING BECOMING LGT/VAR BY EARLY TUESDAY...THEN SOUTHERLY AROUND
10KTS TUESDAY AFTERNOON.
DUNN
&&
.PREV DISCUSSION... /ISSUED 417 AM CDT MON APR 14 2014/
08Z SURFACE ANALYSIS INDICATED A STRONG COLD FRONT MOVING
SOUTHEAST ACROSS THE CWA...LOCATED NEAR A LINE FROM ATHENS TO
WACO TO LAMPASAS. JUST TO THE NORTHWEST OF THIS FRONT...A LINE OF
SCATTERED SHOWERS AND THUNDERSTORMS WAS OBSERVED...LIKELY
ASSOCIATED WITH THE 850 MB REFLECTION OF THE COLD FRONT. AT
0830Z...NONE OF THIS ACTIVITY WAS STRONG IN NATURE...AND AS
ALLUDED TO ABOVE...IT IS ALL ELEVATED IN NATURE OVER THE FRONTAL
INVERSION. REGIONAL SURFACE OBSERVATIONS INDICATE UNSEASONABLY
COLD AIR BEHIND THE FRONT...WITH TEMPERATURES IN THE LOWER 40S
LOCATED OVER WICHITA FALLS. NORTH WINDS WERE ALREADY RELATIVELY
STRONG BEHIND THE FRONT...WITH MANY LOCATIONS OBSERVING WINDS IN
THE 20 TO 25 MPH RANGE EARLY THIS MORNING.
THIS MORNING...WENT AHEAD AND CANCELLED THE SEVERE THUNDERSTORM
WATCH IN COORDINATION WITH THE SPC AND WFO SHV AS THE COLD FRONT
HAD UNDERCUT ALL ONGOING CONVECTION. THIS DOES NOT MEAN IT/S
IMPOSSIBLE TO GET STRONG STORMS THIS MORNING...HOWEVER THE ONLY
STRONG TO MARGINALLY SEVERE STORM HAZARD ASSOCIATED WITH ELEVATED
STORMS IS GOING TO BE IN THE FORM OF HAIL. RAP FORECAST SOUNDINGS
INDICATE THE PRESENCE OF 1000-1500 J/KG OF MUCAPE AVAILABLE FOR
THESE ELEVATED STORMS. DEEP LAYER SHEAR VALUES LOOK
IMPRESSIVE...BUT ARE NOT REALLY RELEVANT FOR THIS ACTIVITY AS THE
BULK OF THE CONTRIBUTION TO THE HIGHER SHEAR VALUES OCCURS BELOW
THE FRONTAL INVERSION. DEEP LAYER BULK SHEAR CALCULATIONS INDICATE
ABOUT 60 KTS OF SHEAR...WHILE EFFECTIVE BULK SHEAR IS MORE
REALISTICALLY AROUND 25 KTS. AS A RESULT...STRONG...BUT LIKELY
UNORGANIZED ELEVATED CONVECTION IS POSSIBLE THIS MORNING. BASED ON
THE RADAR PRESENTATION OF STORMS SO FAR EARLY THIS
MORNING...CHANCES ARE NO LARGE HAIL WILL FALL ACROSS THE
CWA...HOWEVER IF IT DOES OCCUR...HAIL WILL LIKELY BE CLOSE TO 1
INCH OR QUARTER SIZE IN DIAMETER.
REMAINDER OF TODAY...THE 850 MB FRONT WILL SLIDE SOUTHEAST OF THE
CWA BY LATE THIS MORNING...TAKING ALL THUNDERSTORM CHANCES
SOUTHEAST OUT OF THE AREA IN ITS WAKE. RELATIVELY STRONG ISENTROPIC
DOWNGLIDE/COLD AIR ADVECTION WILL DOMINATE THE LOWER TROPOSPHERE
IN THE WAKE OF THIS FRONT. A STRONG UPPER LEVEL LOW PRESSURE
SYSTEM WILL MOVE FROM WEST TO EAST OVER THE SOUTH PLAINS
TODAY...WHICH WILL SPREAD SOME STRONG LARGE SCALE FORCING FOR
ASCENT OVER THE CWA THIS AFTERNOON. HOWEVER...THE LARGE SCALE
FORCING FOR ASCENT ASSOCIATED WITH THIS UPPER LOW IS NOT EXPECTED
TO PENETRATE MUCH DEEPER THAN THE MIDDLE TROPOSPHERE TODAY BECAUSE
THE MIDDLE TO LOW TROPOSPHERE WILL BE DEFINED BY HIGH STATIC
STABILITY. A THERMODYNAMICALLY STABLE LAYER RESISTS VERTICAL
MOTIONS...AND THEREFORE SHOULD PREVENT ANY ADDITIONAL
PRECIPITATION FROM DEVELOPING OVER THE CWA TODAY ASSOCIATED WITH
THIS UPPER LOW. THIS IS SUCH A STRONG UPPER TROUGH THAT IT WOULD
BE A HUGE SURPRISE TO SEE SOME WEAK RADAR RETURNS DEVELOP OVER THE
CWA EARLY THIS AFTERNOON...BUT THE COLD FRONT PUSHING THROUGH THE
AREA JUST LOOKS TOO STRONG AND COLD TO ALLOW FOR MUCH LIFT TO
OCCUR WHERE WE WOULD NEED IT TO GET RAIN SHOWERS...THAT BEING THE
MID TO LOWER TROPOSPHERE.
ASIDE FROM PRECIPITATION CONCERNS...BEHIND THE FRONT WE SHOULD
JUST SEE STRONG NORTH WINDS AND COLD AIR ADVECTION THROUGHOUT THE
DAY TODAY. TEMPERATURES ARE EXPECTED TO INCREASE INTO THE LOWER TO
MID 50S BY LATE THIS AFTERNOON DESPITE THE STRONG COLD AIR
ADVECTION AS SKIES CLEAR OUT RAPIDLY BEHIND THE PASSAGE OF THE
UPPER TROUGH. EVEN THOUGH THE AIR BEHIND THE FRONT WILL REMAIN
COLD...THE SUN ANGLE IS GETTING TOO HIGH FOR US NOT TO HEAT UP A
BIT EVEN WITH JUST A FEW HOURS OF SUNSHINE. A WIND ADVISORY
REMAINS IN EFFECT FOR THE ENTIRE AREA TODAY DUE TO NORTH WINDS OF
25 TO 30 MPH BEHIND THE FRONT. WINDS SHOULD DIMINISH AN HOUR OR
TWO AFTER SUNSET AS HIGH PRESSURE BEGINS TO MOVE INTO THE REGION.
TONIGHT...HIGH PRESSURE IS EXPECTED TO SLIDE SOUTH-SOUTHEAST
ACROSS TEXAS FROM THE TX PANHANDLE TONIGHT. THIS WILL RESULT IN
NEARLY CALM WINDS ACROSS WEST CENTRAL TEXAS...AND LIGHT NORTHERLY
WINDS TO THE EAST. LIGHT WINDS AND CLEAR SKIES WILL MAKE FOR AN
IDEAL RADIATIONAL COOLING ENVIRONMENT RESULTING IN TEMPERATURES
FALLING INTO THE UPPER 20S TO MID 30S ACROSS THE CWA. YES...YOU
READ THAT CORRECTLY...PARTS OF NORTH AND CENTRAL TEXAS ARE
EXPECTED TO FALL BELOW FREEZING TONIGHT INTO TUESDAY MORNING. THIS
IS PUSHING RECORD TERRITORY FOR A LATE FREEZE WHICH IS QUITE
REMARKABLE CONSIDERING RECORDS HAVE BEEN KEPT SINCE THE LATE 1800S
TO EARLY 1900S...SO WE ARE LOOKING AT AN EVENT THAT HAS A RETURN
INTERVAL OF OVER 100 YEARS...FOR NORTH AND CENTRAL TEXAS AT LEAST.
AS A RESULT...THIS FREEZE...ASSUMING IT OCCURS AS FORECAST...HAS
THE POTENTIAL TO DO QUITE A BIT OF DAMAGE TO OUTDOOR PLANTS AS
MOST FOLKS WOULD NOT HAVE WAITED THIS LONG TO GET THEIR SPRING
PLANTING TAKEN CARE OF. AT ANY RATE...THIS IS WHY FREEZE WARNINGS
ARE ISSUED...TO GIVE FOLKS A CHANCE TO PROTECT THEIR PLANTS.
A FREEZE WARNING IS IN EFFECT FROM 1 AM TO 10 AM TONIGHT/TUESDAY
MORNING FOR LOCATIONS ALONG AND NORTHWEST OF A LINE FROM SULPHUR
SPRINGS TO KELLER TO WACO TO LAMPASAS. LOCATIONS JUST SOUTHEAST OF
THIS LINE GENERALLY HAVE FORECAST LOWS AT 33 DEGREES...SO THIS
WARNING MAY BE EXPANDED BASED ON HOW WARM WE GET THIS AFTERNOON
AND BASED ON NEW MODEL GUIDANCE THROUGHOUT THE DAY.
FORTUNATELY...MOST LOCATIONS IN THE FREEZE WARNING SHOULD SEE LOWS
FALL JUST BELOW FREEZING...GENERALLY 30 TO 32 DEGREES.
TEMPERATURES FALLING INTO THE UPPER 20S IS MORE LIKELY NORTH OF
INTERSTATE 30...NEAR THE RED RIVER.
TEMPERATURES ARE MORE LIKELY TO FALL BELOW FREEZING IN RURAL AREAS
MORE SO THAN URBAN AREAS. THE URBAN HEAT ISLAND EFFECT WILL KEEP
MOST OF THE CONCRETED AREAS OF THE METROPLEX ABOVE FREEZING.
TARRANT COUNTY IS INCLUDED IN THE FREEZE WARNING ANYWAYS BECAUSE
THE FAR NORTH AND WESTERN PORTIONS OF THE COUNTY...OUTSIDE OF THE
820 LOOP...ARE MORE LIKELY TO SEE FREEZING TEMPERATURES.
TEMPERATURES ARE EXPECTED TO CLIMB ABOVE FREEZING AREA WIDE AFTER
10 AM TUESDAY MORNING.
FROST IS POSSIBLE IN AREAS NOT INCLUDED IN THE FREEZE WARNING...SO
EVEN IF YOU ARE NOT IN THE FREEZE WARNING AT THIS TIME...IT MAY BE
PRUDENT TO PROTECT YOUR PLANTS ANYWAYS AS A PRECAUTION. THE AIR IS
EXPECTED TO BE VERY DRY...SO WIDESPREAD FROST IS NOT LIKELY...BUT
IT MAY BE BETTER TO BE SAFE THAN SORRY.
REMAINDER OF THE FORECAST...WE WILL WARM UP AFTER TUESDAY...WITH
NO MORE POTENTIAL FROSTS OR FREEZES IN THE FORECAST THROUGH NEXT
WEEKEND. TUESDAY NIGHTS LOWS WILL BE WELL BELOW NORMAL AGAIN...BUT
SHOULD FALL INTO THE MID TO UPPER 30S AT WORST. BY
WEDNESDAY...SOUTH WINDS WILL HELP BRING DEW POINTS BACK UP INTO
THE MID TO UPPER 40S...BRINGING ABOUT A RETURN TO MORE SEASONAL
TEMPERATURES DURING THE DAYTIME AND OVERNIGHT.
OUR NEXT CHANCE OF RAIN STILL LOOKS TO BE THURSDAY...ASSOCIATED
WITH AN UPPER LEVEL TROUGH PROGGED TO MOVE OVER THE SOUTHERN
PLAINS THURSDAY AFTERNOON. HOWEVER...THE ECMWF AND GFS BOTH KEEP
THE BULK OF THE UPPER LEVEL FORCING FOR ASCENT ASSOCIATED WITH
THIS TROUGH NORTH OF THE CWA. ASSUMING THIS VERIFIES...THIS DOES
NOT USUALLY BODE WELL FOR PRECIPITATION CHANCES...EVEN WITH A WEAK
COLD FRONT PUSHING SOUTHEAST ACROSS THE CWA THURSDAY
AFTERNOON/EVENING. THE LOSS OF UPPER LEVEL DYNAMICS USUALLY MAKES
PRECIPITATION ALONG COLD FRONTS ISOLATED AT BEST. THE CANADIAN IS
FURTHER SOUTH WITH THIS UPPER TROUGH...AND THEREFORE HAS MUCH MORE
PRECIPITATION FOR THE CWA. WILL CONTINUE TO MONITOR THE EVOLUTION
OF THIS TROUGH IN FUTURE FORECASTS...HOWEVER FOR NOW JUST KEPT
POPS IN THE 20 TO 30 PERCENT RANGE IN LINE WITH THE GFS/ECMWF
SOLUTION.
AFTER THURSDAY...OUR NEXT SHOT AT RAIN LOOKS TO BE SATURDAY NIGHT
INTO SUNDAY...AS ALL GUIDANCE INDICATES AN UPPER LEVEL TROUGH WILL
MOVE OVER THE SOUTHWESTERN CONUS AND TOWARDS NORTH TX AT THAT
TIME. THE GFS IS THE MOST AGGRESSIVE WITH TAPPING INTO SOME
TROPICAL PACIFIC MOISTURE IN THE UPPER TROPOSPHERE COURTESY OF THE
SUB-TROPICAL JET. AS A RESULT THE GFS GIVES THE CWA A
GOOD...WIDESPREAD ONE HALF TO ONE INCH OF RAINFALL FROM SATURDAY
NIGHT THROUGH SUNDAY. WILL NOT BITE OFF ON THIS SOLUTION QUITE
YET...BUT IT IS A GOOD SIGN THAT AT LEAST ALL MODELS HAVE SOME
VERSION OF THIS TROUGH OVER THE SOUTHWESTERN CONUS. IF THIS
CONSISTENT CONTINUES...POPS WILL BE INCREASED AREA WIDE FOR
SATURDAY NIGHT INTO SUNDAY. THIS DOES NOT LOOK TO BE A GOOD SEVERE
WEATHER SET UP FOR NOW...SO A GOOD WIDESPREAD RAINFALL WITH
EMBEDDED THUNDERSTORMS IS WHAT IS EXPECTED AT THIS TIME. WE WILL
SEE HOW THINGS CHANGE AS WE GET CLOSER TO NEXT WEEKEND OF COURSE.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 55 34 63 42 66 / 10 5 0 0 0
WACO, TX 56 33 63 36 67 / 20 0 0 0 0
PARIS, TX 51 30 59 36 64 / 20 5 0 0 0
DENTON, TX 53 29 62 38 66 / 10 5 0 0 0
MCKINNEY, TX 53 30 62 38 65 / 10 5 0 0 0
DALLAS, TX 56 35 63 42 66 / 10 5 0 0 0
TERRELL, TX 55 33 62 37 65 / 20 5 0 0 0
CORSICANA, TX 54 33 61 38 66 / 20 5 0 0 0
TEMPLE, TX 58 33 64 36 68 / 30 0 0 0 0
MINERAL WELLS, TX 55 32 63 37 69 / 10 0 0 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 1 AM TO 10 AM CDT TUESDAY FOR TXZ091>095-
100>107-115>118-129>133-141>145-156-157-159.
WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR TXZ091>095-100>107-
115>123-129>135-141>148-156>162-174-175.
&&
$$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1010 AM EDT MON APR 14 2014
.SYNOPSIS...
A COLD FRONT FROM THE GREAT LAKES TO SE TX WILL SHIFT EAST TODAY
AND TONIGHT CROSSING THE MID ATLANTIC REGION ON TUESDAY. BEHIND
THE FRONT HIGH PRESSURE WILL BUILD IN FOR WEDNESDAY THROUGH
FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 955 AM EDT MONDAY...
RADAR SHOWING VERY LIGHT RETURNS OVER NE TN/FAR SW VA AND NW
NC. REGIONAL RADAR SHOWS STRONG CONVECTION ACROSS ALABAMA INTO MS
WITH LIGHT TO MODERATE SHOWERS OVER EAST-CENTRAL TN INTO CENTRAL
KY. 12Z SOUNDING INDICATES MID LEVEL LAPSE RATES OF 7.5C/KM. THE
STORM PREDICTION CENTER HAS EXPANDED THEIR GENERAL THUNDERSTORM
RISK TO COVER THE ENTIRE CWA. NOT IMPRESSED WITH THUNDER CHANCES
GIVEN EXTENSIVE CLOUDS IN PLACE BUT ASSOCIATED SHORTWAVE WITH THE
CONVECTION IN ALABAMA IS PROGGED TO SHIFT INTO NC LATE THIS
AFTERNOON. PER LATEST HRRR WHICH IS HANDLING SHOWERS OR LACK
THEREOF OUT THERE NOW...WILL BACK OFF ON HIGHER POPS FOR ABOUT 1-2
HOURS IN THE WEST UNTIL AFTER 19Z/3PM. WILL HAVE ISOLATED THUNDER
IN THE FORECAST THIS AFTERNOON...WITH SOME LIMITED INSTABILITY.
CUT HIGH TEMPS BACK A FEW DEGREES ACROSS THE MOUNTAINS PER LACK OF
SUN AND SHOWERS MOVING IN.
PREVIOUS VALID DISCUSSION...
MUCH BETTER SYNOPTIC SCALE LIFT AFTER 00Z/8PM THIS EVENING. AS
THE COLD FRONT APPROACHES LATE TONIGHT...SURFACE AND LOW LEVEL
WINDS BACK...ADDING THE SOUTHEAST UPSLOPE COMPONENT TO THE STRONG
FORCING. LARGEST PRECIPITATION AMOUNTS WILL BE AFTER MIDNIGHT.
FRONT DOES NOT REACH THE FAR WESTERN PART OF THE FORECAST AREA
BEFORE 12Z/8AM. STAYED CLOSER TO THE WARMER GUIDANCE FOR OVERNIGHT
LOWS. THE LOW LEVEL JET INCREASES OVERNIGHT. HIGHER ELEVATIONS MAY
HAVE GUSTS OF 25 TO 30 MPH.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
AS OF 400 AM EDT MONDAY...
A STRONG COLD FRONT WILL MAKE ITS WAY ACROSS THE FORECAST AREA
BEGINNING TUESDAY MORNING...AND THEREFORE WILL HAVE SEVERAL THINGS
TO KEEP AN EYE. MODELS CONTINUE TO INDICATE A SOUTHWESTERLY 55KT LOW
LEVEL JET DEVELOPING AHEAD OF THE FRONT. INSTABILITY AHEAD OF THE
FRONT WILL BE MARGINAL...RESULTING IN MAINLY HEAVY SHOWER ACTIVITY
WITH ONLY ISOLATED THUNDER AS THE FRONT PASSES. HOWEVER...WITH THE
JET BLOWING JUST OFF THE SURFACE OVER THE MOUNTAINS...WOULD NOT BE
SURPRISED TO SEE SOME OF THE MORE INTENSE SHOWER ACTIVITY DRAW THE
STRONGER WINDS DOWN TO THE GROUND LEVEL.
HIGH PRESSURE WILL BUILD IN QUICKLY AFTER THE COLD FRONT PASSES...
RESULTING IN A ROUGHLY 10MB PRESSURE GRADIENT ACROSS THE FORECAST
AREA FROM MID AFTERNOON THROUGH ALMOST MIDNIGHT. EXPECT STRONG
NORTHWEST WINDS WITH 40 TO 50 MPH GUSTS ACROSS THE MOUNTAINS...WITH
THE STRONGEST GUSTS FOUND ALONG THE BLUE RIDGE PARKWAY SOUTH OF
ROANOKE. THESE GUSTS...WHEN COMBINED WITH PROLONGED RAINFALL...WILL
LIKELY BE ENOUGH TO BRING DOWN A FEW TREES...AND RESULT IN LOCALIZED
POWER OUTAGES.
RAINFALL WILL BE WIDESPREAD AND HEAVY AT TIMES...WITH A STORM TOTAL
AMOUNT OF OVER AN INCH FOR THE ENTIRE FORECAST AREA...WITH AROUND 2
INCHES EXPECTED ALONG THE BLUE RIDGE. MAY SEE LOCALIZED MINOR
FLOODING ISSUES DEVELOP WHERE BANDS OF HEAVY RAIN PASS REPEATEDLY
OVER THE SAME LOCATIONS. RAINFALL MAY ALSO PUSH SOME RIVERS TO
BANKFULL OR MINOR FLOOD LATER IN THE WEEK.
FOR THE FIRST FEW HOURS AFTER FRONTAL PASSAGE...TEMPERATURES WILL
PLUMMET AT A RATE OF 6 TO 9 DEGREES PER HOUR. EXPECT TEMPERATURES TO
APPROACH FREEZING FROM SOUTHEAST WEST VIRGINIA THROUGH THE NORTH
CAROLINA MOUNTAINS BY EARLY EVENING...ALLOWING RAIN SHOWERS TO
CHANGE OVER TO SNOW. WHILE WARM GROUND TEMPERATURES WILL CAUSE SNOW
TO MELT ON CONTACT ACROSS MANY AREAS...MAY SEE UP TO A HALF INCH OF
SNOW ACCUMULATE ALONG OUR MORE PROMINENT WEST FACING SLOPES BEFORE
SNOW SHOWERS END OFF SHORTLY AFTER MIDNIGHT WEDNESDAY.
NEXT WE GET TO DEAL WITH SUB FREEZING TEMPERATURES AREAWIDE BY
SUNRISE WEDNESDAY. EXPECT OVERNIGHT LOWS TO RANGE FROM THE MID 20S
ACROSS SOUTHEAST WEST VIRGINIA TO THE LOW 30S ACROSS THE SOUTHSIDE.
PRECAUTIONS SHOULD BE TAKEN TO PROTECT ANY PLANTS THAT MAY BE KILLED
BY FREEZING TEMPERATURES.
HIGH PRESSURE WILL PASS FROM THE GREAT LAKES TO NEW ENGLAND ON
WEDNESDAY...AND WILL BUILD SOUTHWARD ALONG THE EASTERN FACE OF THE
APPALACHIANS. THE NORTHEASTERLY WIND FLOW AROUND THE HIGH WILL KEEP
COOL CONDITIONS IN PLACE HEADING INTO THE SECOND HALF OF THE
WORKWEEK...WITH FREEZING TEMPERATURES LIKELY AGAIN WEDNESDAY NIGHT.
A GRADUAL WARM UP WILL TAKE PLACE THURSDAY AS WINDS ALOFT BEGIN TO
SHIFT SOUTHWESTERLY AGAIN.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 200 PM EDT SATURDAY...
EXPECT HIGH PRESSURE TO REMAIN IN CONTROL OF THE WEATHER PATTERN FOR
FRIDAY. A COLD FRONT WILL APPROACH FROM THE WEST FRIDAY NIGHT INTO
SATURDAY. GENERALLY FOLLOWED WPCGUIDE FOR POPS. STILL LOOKS LIKE
THE BEST CHANCE FOR WIDESPREAD RAIN WILL OCCUR ON FRIDAY NIGHT
INTO SATURDAY. LEANED TOWARDS THE ECENS MEAN WITH HANDLING THE
SOUTHERN STREAM SYSTEM AND ITS MOISTURE. TEMPERATURES MODERATE
TOWARD NEXT WEEKEND CLOSER TO NORMAL.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
AS OF 130 AM EDT MONDAY...
MVFR CEILINGS HAD FILLED IN OVER THE SOUTHERN APPALACHIANS THIS
MORNING. EXPECTING KDAN AND KROA TO GO IN AND OUT OF MVFR CLOUDS
THROUGH 15Z/11AM.
MODELS BRING THE SHORT WAVE OVER THE TENNESSEE VALLEY ACROSS THE
REGION MAINLY BETWEEN 15Z/11AM AND 21Z/5PM. WITH ALL THE CLOUD
COVER DURING THE DAY...THERE WILL BE ONLY A LIMITED THREAT OF ANY
THUNDER. MODERATE CONFIDENCE THAT VISIBILITIES WILL REMAIN VFR AND
NOT LOWER AS THESE SHOWERS MOVE THROUGH.
THE STRONG COLD FRONT WILL ARRIVE IN THE MOUNTAINS AFTER 05Z/1AM
TUESDAY. THIS RAIN WILL RESULT IN WIDESPREAD IFR TO MVFR CEILINGS
AND VISIBILITIES. THE RAIN MAY BE HEAVY AT TIMES.
LOOKS WET THRU TUESDAY NIGHT. STRONG GUSTY NW WINDS ARE LIKELY
BEHIND THE FRONT TUESDAY AFTERNOON AND NIGHT. DRIER AIR WORKS IN
BEHIND THE SYSTEM FOR WEDNESDAY ALTHOUGH RESIDUAL MOISTURE AND
COLD AIR ALOFT MAY ACT TO KEEP MVFR CIGS OVER THE MOUNTAINS ON
TUESDAY NIGHT. VFR THEN EXPECTED THURSDAY WITH HIGH PRESSURE
RIDGING IN FROM OFF NEW ENGLAND BETWEEN THE EXITING FRONT OFFSHORE
AND THE NEXT COLD FRONT TO THE NW. NEXT COLD FRONT APPROACHES FROM
THE WEST FRIDAY BUT APPEARS SLOW ENOUGH TO MAINTAIN VFR DURING THE
DAY FOR NOW.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS/WP
NEAR TERM...AMS/WP
SHORT TERM...NF
LONG TERM...KK
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
735 AM EDT MON APR 14 2014
.SYNOPSIS...
LOW PRESSURE WAS OVER ILLINOIS WITH A COLD FRONT TRAILING FROM
THE LOW INTO TEXAS. THIS FRONT WILL MOVE EAST TODAY AND TONIGHT
AND WILL CROSS THE MID ATLANTIC REGION ON TUESDAY. BEHIND THE
FRONT HIGH PRESSURE WILL BUILD IN FOR WEDNESDAY THROUGH FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 415 AM EDT MONDAY...
WATER VAPOR LOOP SHOWED A WELL DEFINED SHORT WAVE CROSSING THROUGH
THE TENNESSE VALLEY. THICK CLOUD COVER WAS ALREADY SPREADING INTO
THE COUNTY WARNING AREA FROM THE WEST. SHORT RANGE MODELS
INCLUDING THE LATEST RUC/WRF AND HRRR BRING THE PRECIPITATION
ASSOCIATED WITH THIS WAVE INTO THE WESTERN COUNTY WARNING AREA
BETWEEN 15Z/11AM AND 18Z/2PM.
WITH ALL THE CLOUD COVER DO NOT EXPECT MUCH INSTABILITY. BUFKIT
OFF THE NAM AND GFS SHOWED LOW CAPE VALUES TODAY. HELD PROBABILITY
OF THUNDER TO SLIGHT CHANCE. DO EXPECT ISOLATED TO SCATTERED
SHOWERS AHEAD OF THE TENNESSEE VALLEY SHORT WAVE...WITH THE BETTER
AREAL COVERAGE IN THE MOUNTAINS THROUGH NOON. HIGH TODAY WILL
STILL BE ABOVE NORMAL BUT ONLY A SMALL RISE FROM THE CURRENT MILD
TEMPERATURES.
MUCH BETTER SYNOPTIC SCALE LIFT AFTER 00Z/8PM THIS EVENING. AS THE
COLD FRONT APPROACHES LATE TONIGHT...SURFACE AND LOW LEVEL WINDS
BACK...ADDING THE SOUTHEAST UPSLOPE COMPONENT TO THE STRONG
FORCING. LARGEST PRECIPITATION AMOUNTS WILL BE AFTER MIDNIGHT.
FRONT DOES NOT REACH THE FAR WESTERN PART OF THE FORECAST AREA
BEFORE 12Z/8AM. STAYED CLOSER TO THE WARMER GUIDANCE FOR OVERNIGHT
LOWS. THE LOW LEVEL JET INCREASES OVERNIGHT. HIGHER ELEVATIONS
MAY HAVE GUSTS OF 25 TO 30 MPH.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
AS OF 400 AM EDT MONDAY...
A STRONG COLD FRONT WILL MAKE ITS WAY ACROSS THE FORECAST AREA
BEGINNING TUESDAY MORNING...AND THEREFORE WILL HAVE SEVERAL THINGS
TO KEEP AN EYE. MODELS CONTINUE TO INDICATE A SOUTHWESTERLY 55KT LOW
LEVEL JET DEVELOPING AHEAD OF THE FRONT. INSTABILITY AHEAD OF THE
FRONT WILL BE MARGINAL...RESULTING IN MAINLY HEAVY SHOWER ACTIVITY
WITH ONLY ISOLATED THUNDER AS THE FRONT PASSES. HOWEVER...WITH THE
JET BLOWING JUST OFF THE SURFACE OVER THE MOUNTAINS...WOULD NOT BE
SURPRISED TO SEE SOME OF THE MORE INTENSE SHOWER ACTIVITY DRAW THE
STRONGER WINDS DOWN TO THE GROUND LEVEL.
HIGH PRESSURE WILL BUILD IN QUICKLY AFTER THE COLD FRONT PASSES...
RESULTING IN A ROUGHLY 10MB PRESSURE GRADIENT ACROSS THE FORECAST
AREA FROM MID AFTERNOON THROUGH ALMOST MIDNIGHT. EXPECT STRONG
NORTHWEST WINDS WITH 40 TO 50 MPH GUSTS ACROSS THE MOUNTAINS...WITH
THE STRONGEST GUSTS FOUND ALONG THE BLUE RIDGE PARKWAY SOUTH OF
ROANOKE. THESE GUSTS...WHEN COMBINED WITH PROLONGED RAINFALL...WILL
LIKELY BE ENOUGH TO BRING DOWN A FEW TREES...AND RESULT IN LOCALIZED
POWER OUTAGES.
RAINFALL WILL BE WIDESPREAD AND HEAVY AT TIMES...WITH A STORM TOTAL
AMOUNT OF OVER AN INCH FOR THE ENTIRE FORECAST AREA...WITH AROUND 2
INCHES EXPECTED ALONG THE BLUE RIDGE. MAY SEE LOCALIZED MINOR
FLOODING ISSUES DEVELOP WHERE BANDS OF HEAVY RAIN PASS REPEATEDLY
OVER THE SAME LOCATIONS. RAINFALL MAY ALSO PUSH SOME RIVERS TO
BANKFULL OR MINOR FLOOD LATER IN THE WEEK.
FOR THE FIRST FEW HOURS AFTER FRONTAL PASSAGE...TEMPERATURES WILL
PLUMMET AT A RATE OF 6 TO 9 DEGREES PER HOUR. EXPECT TEMPERATURES TO
APPROACH FREEZING FROM SOUTHEAST WEST VIRGINIA THROUGH THE NORTH
CAROLINA MOUNTAINS BY EARLY EVENING...ALLOWING RAIN SHOWERS TO
CHANGE OVER TO SNOW. WHILE WARM GROUND TEMPERATURES WILL CAUSE SNOW
TO MELT ON CONTACT ACROSS MANY AREAS...MAY SEE UP TO A HALF INCH OF
SNOW ACCUMULATE ALONG OUR MORE PROMINENT WEST FACING SLOPES BEFORE
SNOW SHOWERS END OFF SHORTLY AFTER MIDNIGHT WEDNESDAY.
NEXT WE GET TO DEAL WITH SUB FREEZING TEMPERATURES AREAWIDE BY
SUNRISE WEDNESDAY. EXPECT OVERNIGHT LOWS TO RANGE FROM THE MID 20S
ACROSS SOUTHEAST WEST VIRGINIA TO THE LOW 30S ACROSS THE SOUTHSIDE.
PRECAUTIONS SHOULD BE TAKEN TO PROTECT ANY PLANTS THAT MAY BE KILLED
BY FREEZING TEMPERATURES.
HIGH PRESSURE WILL PASS FROM THE GREAT LAKES TO NEW ENGLAND ON
WEDNESDAY...AND WILL BUILD SOUTHWARD ALONG THE EASTERN FACE OF THE
APPALACHIANS. THE NORTHEASTERLY WIND FLOW AROUND THE HIGH WILL KEEP
COOL CONDITIONS IN PLACE HEADING INTO THE SECOND HALF OF THE
WORKWEEK...WITH FREEZING TEMPERATURES LIKELY AGAIN WEDNESDAY NIGHT.
A GRADUAL WARM UP WILL TAKE PLACE THURSDAY AS WINDS ALOFT BEGIN TO
SHIFT SOUTHWESTERLY AGAIN.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 200 PM EDT SATURDAY...
EXPECT HIGH PRESSURE TO REMAIN IN CONTROL OF THE WEATHER PATTERN FOR
FRIDAY. A COLD FRONT WILL APPROACH FROM THE WEST FRIDAY NIGHT INTO
SATURDAY. GENERALLY FOLLOWED WPCGUIDE FOR POPS. STILL LOOKS LIKE
THE BEST CHANCE FOR WIDESPREAD RAIN WILL OCCUR ON FRIDAY NIGHT
INTO SATURDAY. LEANED TOWARDS THE ECENS MEAN WITH HANDLING THE
SOUTHERN STREAM SYSTEM AND ITS MOISTURE. TEMPERATURES MODERATE
TOWARD NEXT WEEKEND CLOSER TO NORMAL.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AS OF 130 AM EDT MONDAY...
MVFR CEILINGS HAD FILLED IN OVER THE SOUTHERN APPALACHIANS THIS
MORNING. EXPECTING KDAN AND KROA TO GO IN AND OUT OF MVFR CLOUDS
THROUGH 15Z/11AM.
MODELS BRING THE SHORT WAVE OVER THE TENNESSEE VALLEY ACROSS THE
REGION MAINLY BETWEEN 15Z/11AM AND 21Z/5PM. WITH ALL THE CLOUD
COVER DURING THE DAY...THERE WILL BE ONLY A LIMITED THREAT OF ANY
THUNDER. MODERATE CONFIDENCE THAT VISIBILITIES WILL REMAIN VFR AND
NOT LOWER AS THESE SHOWERS MOVE THROUGH.
THE STRONG COLD FRONT WILL ARRIVE IN THE MOUNTAINS AFTER 05Z/1AM
TUESDAY. THIS RAIN WILL RESULT IN WIDESPREAD IFR TO MVFR CEILINGS
AND VISIBILITIES. THE RAIN MAY BE HEAVY AT TIMES.
LOOKS WET THRU TUESDAY NIGHT. STRONG GUSTY NW WINDS ARE LIKELY
BEHIND THE FRONT TUESDAY AFTERNOON AND NIGHT. DRIER AIR WORKS IN
BEHIND THE SYSTEM FOR WEDNESDAY ALTHOUGH RESIDUAL MOISTURE AND
COLD AIR ALOFT MAY ACT TO KEEP MVFR CIGS OVER THE MOUNTAINS ON
TUESDAY NIGHT. VFR THEN EXPECTED THURSDAY WITH HIGH PRESSURE
RIDGING IN FROM OFF NEW ENGLAND BETWEEN THE EXITING FRONT OFFSHORE
AND THE NEXT COLD FRONT TO THE NW. NEXT COLD FRONT APPROACHES FROM
THE WEST FRIDAY BUT APPEARS SLOW ENOUGH TO MAINTAIN VFR DURING THE
DAY FOR NOW.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...NF
LONG TERM...KK
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
644 AM CDT MON APR 14 2014
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 345 AM CDT MON APR 14 2014
MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES TODAY AND
THEN TUESDAY NIGHT INTO WEDNESDAY.
SURFACE ANALYSIS SHOWS AN AREA OF LOW PRESSURE OVER NORTHERN
ILLINOIS. LOCAL AND REGIONAL RADARS SHOWING THE DEFORMATION BAND
OF PRECIPITATION ON THE NORTHWEST SIDE OF THE LOW EXTENDS FROM
SOUTHERN IOWA ACROSS THE AREA INTO EASTERN LAKE SUPERIOR. COLDER
AIR HAS FILTERED IN AND CHANGED MOST OF THE PRECIPITATION OVER TO
SOME LIGHT SNOW. THE PRECIPITATION IS MOVING TO THE NORTHEAST AND
THE 14.05Z HRRR SEEMS TO HAVE A GOOD HANDLE ON THE CURRENT
SITUATION. IT INDICATES THAT BY 12Z THE BACK EDGE OF THE
PRECIPITATION COMING OUT OF SOUTHERN IOWA WILL HAVE SHIFTED INTO
SOUTHERN WISCONSIN WITH THE WESTERN EDGE INTO THE WESTERN AND
CENTRAL PARTS OF WISCONSIN. WILL ADJUST THE MORNING SNOW CHANCES
BASED ON RADAR TRENDS...BUT EXPECT THAT THE MAJORITY OF THE
ACTIVITY SHOULD BE EAST OF THE FORECAST AREA BY 12Z AND THEN WHAT
IT IS LEFT WILL QUICKLY DISSIPATE BY THE MID MORNING HOURS.
HIGH PRESSURE WILL THEN BUILD IN OVER THE UPPER MIDWEST AND LINGER
INTO TUESDAY BEFORE DEPARTING TO THE NORTHEAST. THE HIGH WILL HELP
TO KEEP TEMPERATURES BELOW NORMAL WITH HIGHS TODAY ONLY IN THE
30S FOR THE ENTIRE AREA AND THEN IN THE 30S AND 40S FOR TUESDAY.
THE NEXT CHANCE FOR SOME PRECIPITATION WILL START TO COME IN
TUESDAY NIGHT AND CONTINUE INTO WEDNESDAY. THIS WILL BE IN
RESPONSE TO A SHORT WAVE TROUGH THAT WILL CROSS THE NORTHERN
ROCKIES TUESDAY NIGHT AND MOVE OUT OVER THE UPPER MIDWEST
WEDNESDAY. THE BEST PV ADVECTION IN THE 500-300 MB LAYER IS
EXPECTED TO REMAIN NORTHWEST OF THE AREA THROUGH WEDNESDAY...BUT
THE WAVE SHOULD STILL BE ABLE TO PRODUCE AT LEAST SOME WEAK PV
ADVECTION OVER THE NORTHWEST SECTIONS OF THE FORECAST AREA. LOW
PRESSURE AT THE SURFACE IS EXPECTED TO MOVE EAST ACROSS SOUTH
DAKOTA DURING THE DAY WEDNESDAY WITH A WARM FRONT EXTENDING EAST
INTO WISCONSIN. WEAK FRONTOGENESIS IN THE 1000-700 MB LAYER IS
EXPECTED TO DEVELOP ALONG AND NORTH OF THE WARM FRONT ACROSS
MINNESOTA AND WISCONSIN. THE WARM AIR ADVECTION AHEAD OF THE SHORT
WAVE TROUGH AND SURFACE LOW IS EXPECTED TO PRODUCE 5 TO 8 UBAR/S
OF UP GLIDE ON THE 290K ISENTROPIC SURFACE. WITH THE FORCING FROM
THE SHORT WAVE TROUGH AND THE LOW LEVEL FRONTOGENESIS AND
ISENTROPIC UP GLIDE...EXPECT TO SEE PRECIPITATION BEGIN TO DEVELOP
ALONG AND NORTH OF THE WARM FRONT LATE TUESDAY NIGHT AND CONTINUE
INTO WEDNESDAY. WILL START OUT WITH SOME SMALL CHANCES ALONG AND
NORTH OF INTERSTATE 94 LATE TUESDAY NIGHT AND THEN SPREAD THE
CHANCES SOUTH TO ABOUT THE IOWA/MINNESOTA BORDER WEDNESDAY WHILE
INCREASING TO 50 PERCENT ACROSS THE FAR NORTH. BUFKIT SOUNDINGS
INDICATE THAT ICE WILL BE PRESENT IN THE CLOUDS AND THERE SHOULD
NOT BE A WARM LAYER TO DEAL WITH...SO THE PRECIPITATION TYPE
SHOULD BE CONTROLLED BY THE BOUNDARY LAYER TEMPERATURES. WILL
START WITH ALL SNOW TUESDAY NIGHT GOING TO RAIN WEDNESDAY AS
READINGS WARM INTO THE 40S AND 50S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 AM CDT MON APR 14 2014
SLOW AND COMPLICATED UPPER AIR PATTERN WILL KEEP THE PRECIPITATION
CHANCES IN THE FORECAST THROUGH THE WEEKEND. ONCE THE FIRST SHORT
WAVE TROUGH MOVES PAST THE REGION WEDNESDAY NIGHT...ALL THE MODELS
SHOW A CUT OFF LOW FORMING OVER SOUTHERN SASKATCHEWAN FROM A
STRONG NORTHERN STREAM SHORT WAVE TROUGH COMING DOWN FROM THE
NORTHERN CANADA. THIS IS EXPECTED TO KEEP THE MEAN LONG WAVE
TROUGH ALONG AND EAST OF THE ROCKIES WITH SEVERAL SHORT WAVE
TROUGHS COMING THROUGH THIS LONG WAVE TROUGH. THE CLOSED LOW
SHOULD THEN OPEN UP AND START TO MOVE EAST WITH THE LONG WAVE
TROUGH PASSING OVER FOR THE WEEKEND. WITHIN THIS EXTENDED PERIOD
OF PRECIPITATION CHANCES...THE BEST CHANCES LOOK TO OCCUR THURSDAY
NIGHT INTO FRIDAY WHEN A STRONG SHORT WAVE TROUGH IS SHOWN BY THE
MODELS TO MOVE ACROSS THE REGION. TEMPERATURES STILL LOOK TO BE
COOL ENOUGH FOR SNOW OR A RAIN/SNOW MIX AT NIGHT GOING TO RAIN
DURING THE DAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 644 AM CDT MON APR 14 2014
NOW THAT THE SNOW HAS EXITED EAST OF THE AREA...MAIN CONCERN TURNS
TO WINDS AND CLOUD COVER. LOOKING FOR MVFR CLOUDS TO SCATTER KRST
BY 13Z AND KLSE BY 15Z...LEAVING A VFR CIG OF MID-
CLOUD/ALTOCUMULUS. STEEPENING LAPSE RATES THIS AFTERNOON EXPECTED
TO PRODUCE CUMULUS WITH VFR BASES IN THE 4-5KFT RANGE. LOOK FOR
THIS TO SCATTER OUT AFTER SUNSET WITH LOSS OF SURFACE HEATING.
OTHERWISE...A TIGHT PRESSURE GRADIENT WILL EXIST ACROSS THE AREA
TODAY BETWEEN LOW PRESSURE OVER THE GREAT LAKES AND HIGH PRESSURE
BUILDING IN FROM THE NORTHERN PLAINS. AS A RESULT...PLAN ON
NORTH/NORTHWEST WINDS IN THE 15-25KT RANGE SUSTAINED WITH GUSTS
AROUND 30KT. THIS WINDS WILL SUBSIDE RAPIDLY THIS EVENING AFTER
SUNSET WITH LOSS OF DEEPER MIXING AND AS HIGH PRESSURE BUILDING
OVERHEAD.
&&
.HYDROLOGY...
ISSUED AT 345 AM CDT MON APR 14 2014
PARTS OF SOUTHWEST WISCONSIN RECEIVED BETWEEN 2 AND 4 INCHES OF
RAIN OVER THE WEEKEND. THIS HAS RESULTED IN SATURATED SOILS AND
RUNOFF INTO AREAS STREAMS. THIS HAS RESULTED IN MAINLY IN BANK
RISES BUT THE LATEST FORECASTS INDICATE SOME MINOR FLOODING IS
POSSIBLE ALONG THE KICKAPOO IN THE VICINITY OF READSTOWN. SOME
FLOODING LATER THIS WEEK IS POSSIBLE ALONG THE MISSISSIPPI RIVER
AS RUNOFF FROM THE SNOWMELT UPSTREAM AND THE RECENT RAINS MOVES
DOWNSTREAM.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...DAS
HYDROLOGY...04
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1002 AM MDT MON APR 14 2014
.UPDATE...
ISSUED AT 1002 AM MDT MON APR 14 2014
CURRENT FORECAST TRENDS STILL ON TRACK. STORM SYSTEM HAS PUSHED
EAST AND SOUTHEAST OF THE AREA. STILL SOME LINGERING SNOW SHOWERS
ALONG THE CONTINENTAL DIVIDE OF SUMMIT AND GRAND COUNTIES AND
ALONG THE PARK AND GORE RANGES OF WESTERN JACKSON COUNTY AS NOTED
BY WEB CAMS. AS DRIER AND MORE SUBSIDENT AIR SPREADS INTO THE
REGION THIS MORNING...THESE LIGHT SHOWERS SHOULD BE COMING TO AN
END. NORTHERLY FLOW ALOFT BECOMES MORE NORTHWEST DURING THE
AFTERNOON AS UPPER TROUGH MOVES INTO THE CENTRAL PLAINS AND UPPER
RIDGE BUILDS INTO THE GREAT BASIN. LATEST RAP INDICATING A WEAK
MID LEVEL SHORTWAVE MOVING ACROSS NEBRASKA DURING THE AFTERNOON.
THERE IS SOME WEAK ASCENT ASSOCIATED WITH THIS WAVE...LOOKS TO
REMAIN NORTHEAST OF COLORADO. BOTH THE RAP AND HRRR INDICATE
SURFACE CAPE VALUES OF 100 J/KG FAR ACROSS LOGAN...SEDGWICK AND
PHILLIPS COUNTIES BY 21Z. THERE IS ALSO SOME CIN AS WELL. NOT
EXPECTING ANY SHOWERS WITH THIS WAVE...PERHAPS A BIT MORE MID
LEVEL CLOUD FAR NORTHEAST CORNER. COOLER AIRMASS TO BE OVER THE
AREA TODAY...HIGHS IN THE 40S ACROSS NORTHEAST PLAINS STILL
LOOKING GOOD. MAY NEED TO LOWER THE HIGHS ACROSS ZONE 36 AND 41
AS THIS AREA RECEIVED DECENT SNOW.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 344 AM MDT MON APR 14 2014
THE STORM SYSTEM THAT BROUGHT THE COLD AND SNOW WILL CONTINUE TO
MOVE OFF TO THE EAST THIS MORNING. LIGHT SNOW WILL TAPER OFF DURING
THE EARLY MORNING HOURS FROM WEST TO EAST. THE LIGHT SNOW COULD
LINGER INTO THE MID MORNING OVER THE EASTERN PLAINS. DRIER MOVING IN
BEHIND THIS SYSTEM WILL BRING MOSTLY SUNNY SKIES BY AFTERNOON.
NORTHERLY FLOW ALOFT AND AT THE SURFACE WILL PREVAIL BEHIND THE
EXITING SYSTEM TODAY. THIS WILL RESULT IN COOL TEMPERATURES WITH
HIGHS AROUND 40 DEGREES OVER NORTHEAST COLORADO. WARMER AIR ALOFT
WILL START TO MOVE OVER COLORADO TONIGHT...HOWEVER LOWS WILL BE
BELOW NORMAL FOR THIS TIME OF YEAR.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 344 AM MDT MON APR 14 2014
ON TUESDAY IT WILL BE WARMER...A RIDGE OF HIGH PRESSURE
ACCOMPANIED BY A DRY NORTHWESTERLY FLOW ALOFT WILL BE OVER NERN
CO. THE FLOW ALOFT TRANSITIONS TO MORE OF A WESTERLY FLOW BY 00Z
WEDNESDAY AS THE NEXT SYSTEM APPROACHES THE STATE FM THE NORTHERN
ROCKIES. TUESDAY NIGHT...MOISTURE WILL INCREASE OVER THE MOUNTAINS
AS THE NEXT UPPER TROUGH CONTINUES TO APPROACH NRN CO. THIS SYSTEM
WILL NOT BE AS WELL ORGANIZED AS THE ONE OVER THE WEEKEND BUT
COULD STILL SPREAD A FAIR AMOUNT OF LIGHT TO MODERATE PCPN OVER
THE REGION. AFTER 06Z WEDNESDAY...THE MDLS GENERATE SOME QPF IN
THE MOUNTAINS NORTH OF INTERSTATE 70. BY 12Z WEDNESDAY...A WEAK
UPPER TROUGH AXIS BRUSHES ACROSS NERN CO...WITH A COLD FRONT
MOVING INTO THE NERN CO LATE WEDNESDAY MORNING AND AFTN. NOT MUCH
PCPN INITIALLY BUT A FAIRLY GUSTY WINDS ACROSS THE NERN PLAINS
ACCOMPANYING THE COLD FRONT. SHALLOW UPSLOPE WILL DEVELOP ALONG
THE FRONT RANGE BY 00Z THURSDAY FOLLOWING THE PASSAGE OF THE COLD
FRONT. WEAK QG ASCENT AT THE SFC AND ALOFT...STRONGEST FM 06Z TO
18Z THURSDAY AS THE MAIN AXIS ASSOCIATED WITH THE UPPER TROUGH
MOVES ACROSS NRN CO. BY THE AFTN...DECREASING QG ASCENT WILL
DEVELOP ALOFT BUT SHALLOW ANTICYCLONIC UPSLOPE WILL ALLOW FOR
CHANCE OF PRECIPITATION TO LINGER INTO THURSDAY EVENING. THURSDAY
NIGHT INTO FRIDAY...A DRY AND SUBSIDENT NORTHWESTERLY FLOW ALOFT
WILL BE OVER CO AHEAD OF ANOTHER RIDGE OF HIGH PRESSURE. AS A
RESULT...DRY AND WARMER CONDITIONS WILL RETURN FRIDAY. OVER THE
WEEKEND...A WEAK UPPER TROUGH WILL APPROACH COLORADO FM THE DESERT
SOUTHWEST WITH A CHANCE OF RAIN/SNOW DEVELOPING IN THE MOUNTAINS
IN THE AFTN...WITH A SLIGHT CHANCE OF RAIN POSSIBLY SPREADING INTO
THE NERN PLAINS SATURDAY NIGHT INTO SUNDAY. TEMPERATURES ARE
PROGGED TO REMAIN MILD OVER THE WEEKEND.
&&
.AVIATION...(FOR THE TAFS THROUGH 00Z TUESDAY AFTERNOON)
ISSUED AT 1002 AM MDT MON APR 14 2014
WINDS TRYING TO SHIFT TO THE NORTHWEST ACROSS THE AREA
AIRPORTS...STILL MORE WESTERLY AT KDEN AND KAPA. SHOULD BECOME
MORE NORTHWEST WITHIN THE NEXT HALF HOUR...THOUGH...AS NORTHWEST
FLOW JUST OFF THE SURFACE MIXES DOWN WITH HELP FROM SUBSIDENCE.
WILL CONTINUE THE TREND OF CURRENT TAFS FOR THE UPCOMING 18Z
ISSUANCE...WITH WINDS GRADUALLY SHIFTING CLOCKWISE TO THE
NORTHEAST THEN SOUTHEAST DURING THE AFTERNOON...BEFORE GOING TO
DRAINAGE THIS EVENING. VFR TO CONTINUE WITH UNLIMITED CEILINGS.
THERE MAY BE A BIT MORE MID LEVEL CLOUD LATER THIS AFTERNOON WITH
A PASSING MID LEVEL WAVE...APPEARS THIS WILL REMAIN WELL NORTHEAST
OF DENVER. SOUTHERLY WINDS TO PREVAIL TUESDAY...MAY BE A BIT MORE
SOUTHEAST AT KDEN AND KAPA BY THE AFTERNOON.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...D-L
SHORT TERM...MEIER
LONG TERM...COOPER
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS MIAMI FL
126 PM EDT MON APR 14 2014
.AVIATION...
VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST. IT DOES NOT
APPEAR TO BE A REPEAT PERFORMANCE OF IFR CIGS/VSBY AT APF TONIGHT
AS MIXING SHOULD BE TOO STRONG AND MID LEVEL CLOUDS WILL BE ON THE
INCREASE. THE OTHER CONCERN WILL BE MOISTURE INCREASE/INSTABILITY ON
TUESDAY AS A COLD FRONT MOVES INTO CENTRAL FLORIDA. CURRENT
THINKING IS THAT ANY CONVECTION WILL BE TOO ISOLATED AND TOO LATE
IN THE FORECAST TO MENTION AT THIS TIME WITH THE MAIN THREAT AFT
18Z.
KOB
&&
.PREV DISCUSSION... /ISSUED 949 AM EDT MON APR 14 2014/
UPDATE...
A PERSISTENT GROUP OF SHOWERS WILL CONTINUE ACROSS THE LOCAL
ATLANTIC WATERS THIS MORNING. THE INTERACTION OF THE SOUTH-
SOUTHWESTERLY LAND BREEZE AND THE MEAN EASTERLY FLOW COULD HELP IN
THE DEVELOPMENT OF BRIEF WATERSPOUTS WITHIN THIS ACTIVITY. THIS
RISK WILL DECREASE RAPIDLY AS THE LAND BREEZE WEAKENS WITH THE
TEMPERATURE RISING LATE THIS MORNING. LATEST HRRR SHOWS SHOWERS
DEVELOPING THIS AFTERNOON AND EVENING ACROSS THE INTERIOR AND WEST
DUE TO THE INTERACTION OF EASTERLY FLOW AND THE WEST COAST SEA
BREEZE. TEMPERATURES ARE EXPECTED TO REACH THE LOW 90S ACROSS THAT
AREA ALSO #ISMELLSUMMER.
PREV DISCUSSION... /ISSUED 745 AM EDT MON APR 14 2014/
AVIATION...
MOSTLY VFR CONDITIONS ARE EXPECTED ACROSS SOUTH FLORIDA WITH THE
EXCEPTION OF PERIODIC MVFR CIGS ALONG THE EAST COAST EARLY IN THE
FORECAST AS A FEW SHOWERS MOVE IN FROM THE ATLANTIC, ESPECIALLY
FROM FLL TO PBI. ALSO, IFR CONDITIONS DEVELOPED OVER THE FAR
WESTERN PENINSULA AND ADVECTED OVER THE APF TERMINAL FIELD. THIS
SHOULD BEGIN TO LIFT OUT AFT 13-14Z. SURFACE WIND IS LIGHT E-SE
AND THIS WILL INCREASE TO 10-12KT AFT 14-15Z WITH A SEA BREEZE
DEVELOPING AT APF AROUND 16-17Z.
KOB
PREV DISCUSSION... /ISSUED 241 AM EDT MON APR 14 2014/
UNSETTLED WEATHER IS EXPECTED THIS WEEK OVER SOUTH FLORIDA...
SHORT TERM...
HIGH PRESSURE WILL CONTINUE TO MOVE FURTHER EAST INTO THE ATLANTIC
WATERS THROUGH TUESDAY ALLOWING FOR A COLD FRONT OVER THE CENTRAL
UNITED STATES TO MOVE SOUTHEAST INTO NORTH FLORIDA. THIS WILL
ALLOW FOR THE WIND FLOW TO SWING FROM AN EASTERLY DIRECTION TODAY
TO A SOUTHERLY DIRECTION ON TUESDAY OVER SOUTH FLORIDA ALLOWING
FOR MOISTURE TO WORK INTO THE AREA LATE TONIGHT INTO TUESDAY.
THEREFORE...THE WEATHER SHOULD REMAIN DRY TODAY INTO TONIGHT OVER
MOST OF SOUTH FLORIDA. THE ONLY EXCEPTION TO THIS IS OVER THE LAKE
OKEECHOBEE REGION AND PALM BEACH COUNTY TODAY WHERE A FEW SHOWERS
COULD DEVELOP DUE TO THE SEA BREEZE AND LAKE BREEZE
COLLISION...AND ALONG THE EAST COAST METRO AREAS TONIGHT. ON
TUESDAY...THERE WILL BE A CHANCE OF SHOWERS OVER MOST OF SOUTH
FLORIDA WITH EVEN SOME THUNDERSTORMS OVER SOUTH FLORIDA.
THE COLD FRONT WILL CONTINUE TO MOVE SOUTHWARD AND THROUGH SOUTH
FLORIDA TUESDAY NIGHT BRINGING IN SOME DRIER WEATHER. THE DRY
WEATHER WILL NOT LAST LONG...AS THE FRONT WILL COME BACK
NORTHWARD LATE WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT AS A WARM
FRONT. SO THE WEATHER OVER SOUTH FLORIDA FOR TUESDAY NIGHT WILL BE
DRY WITH ISOLATED TO SCATTERED SHOWERS FOR WEDNESDAY INTO
WEDNESDAY NIGHT.
LONG TERM...
THE FRONT WILL CONTINUE TO MOVE NORTHWARD INTO CENTRAL FLORIDA
LATE THIS WEEK...AS WEAK LOW PRESSURE DEVELOPS ALONG THE FRONT IN
THE GULF OF MEXICO AND MOVES ACROSS NORTH FLORIDA. THIS WILL ALLOW
FOR MOISTURE TO REMAIN OVER SOUTH FLORIDA LATE THIS WEEK WITH A
CHANCE OF SHOWERS AND EVEN A FEW THUNDERSTORMS.
THE LOW WILL CONTINUE TO MOVE NORTHEAST INTO THE MID ATLANTIC
STATES...AS THE FRONT REMAINS NEARLY STATIONARY OVER NORTH
FLORIDA. THIS WILL KEEP THE LOW LEVEL MOISTURE IN PLACE OVER SOUTH
FLORIDA THIS WEEKEND ALLOWING FOR ISOLATED TO SCATTERED SHOWERS
OVER SOUTH FLORIDA.
MARINE...
THE EASTERLY WINDS TODAY WILL SWING SLOWLY TO A SOUTHERLY DIRECTION
BY TUESDAY...BEFORE GOING NORTHERLY ON WEDNESDAY. THE WIND SPEEDS
WILL BE 15 KNOTS OR LESS TODAY THROUGH WEDNESDAY. THIS WILL KEEP
THE SEAS BELOW 7 FEET IN BOTH THE ATLANTIC AND GULF WATERS THROUGH
WEDNESDAY.
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
255 PM CDT MON APR 14 2014
.DISCUSSION...
1205 PM CDT
CHALLENGING FORECAST CONTINUES THROUGH THE EVENING WITH PRECIP
COVERAGE...INTENSITY...AND TYPE BEING THE MAIN FOCUS. LARGE SCALE
UPPER TROUGH COVERING THE MID SECTION OF THE COUNTRY CONTINUES TO
PIVOT EASTWARD PUSHING COLDER AIR INTO THE REGION. SUBTLE WAVES
TRAVERSING THE FLOW CONTINUE TO WORK WITH COLD ADVECTION TO BRING
PRECIP DEVELOPMENT. SURFACE TEMPS HAVE WARMED CENTRAL AND
SOUTHEAST WHICH IS SUPPORTIVE OF MORE RAIN BUT TEMPERATURES WILL
LIKELY COOL INTO THE AFTERNOON FROM THE NORTHWEST.
THEREFORE...PRECIP TYPE THROUGH EARLY AFTERNOON WILL LIKELY BE
RAIN OR SNOW EXCEPT FOR FAR SOUTHEAST AREAS THAT WOULD SEE
RAIN...THOUGH PRECIP CHANCES ARE LOWER THERE. WATER VAPOR SHOWS A
MORE ORGANIZED SHORTWAVE STARTING TO EJECT NORTHEAST FROM
SOUTHWEST MISSOURI AND EASTERN OKLAHOMA AND KANSAS. THIS WAVE WILL
LIFT INTO THE AREA LATE THIS AFTERNOON INTO THE EARLY EVENING AND
TIGHTEN THE MID LEVEL BAROCLINIC ZONE RESULTING IN INTENSIFYING
FRONTOGENESIS. RADAR MOSAIC SHOWS BANDS OF PRECIP DEVELOPING
NORTHEASTWARD IN CONJUNCTION WITH THIS FEATURE. WILL CONTINUE WITH
THE IDEA OF A MORE FOCUSED PERIOD OF PRECIPITATION LATE THIS
AFTERNOON INTO THE EVENING BUT HAVE TRIED TO REFINE DETAILS. WHILE
PRECIP WILL CONTINUE ON AND OFF THROUGH THE AFTERNOON...HAVE
SLOWED THE PERIOD OF BETTER COVERAGE/INTENSITY SLIGHTLY. FORECAST
SOUNDINGS/CONCEPTUAL MODELS SUPPORT ALL SNOW WITHIN THE MOST
INTENSE BAND THANKS TO WELL ALIGNED ASCENT WITHIN THE SNOW GROWTH
ZONE AND COOLING LOW LEVEL TEMP PROFILES. EXPECT THAT THERE WILL
BE A CORRIDOR OF MODERATE SNOW WITHIN A LARGER AREA OF LESS
INTENSE PRECIP THAT WILL DEVELOP NORTHWARD ALONG A LINE FROM
ROUGHLY CHICAGO TO MENDOTA...THEN PIVOT EASTWARD INTO THE EVENING.
MUCH OF THE EVENING RUSH HOUR IN THE CHICAGO METRO LOOKS TO FALL
INTO THE PERIOD OF MORE INTENSE SNOWFALL...WHICH MAY LAST A FEW
HOURS. THE VORT MAX LIFTS NORTHEAST WHICH MAY BRING A LULL IN THE
PRECIP EARLY THIS EVENING BUT LARGER SCALE FORCING INCREASES TO
THE EAST SO THERE MAY BE RE-INTENSIFICATION OVER NORTHWEST INDIANA
BY MID EVENING BEFORE PRECIP EXITS LATE EVENING. TEMPERATURES
WILL LIKELY COOL INTO THE MID 30S LATER TODAY AND SNOW SHOULD FALL
AT AN INTENSE ENOUGH RATE TO PROVIDE FOR ACCUMULATION ON GRASSY
SURFACES AND SLUSHY ACCUMULATION ON ROADS. WILL CONTINUE WITH THE
IDEA OF AROUND AN INCH OF ACCUMULATION.
MDB
//PREV DISCUSSION...
330 AM CDT
THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY
IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS.
THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST
CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL
BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD
LEVELS TONIGHT.
THIS MORNING...
THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO
EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES
60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE
DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING
NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND
MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET
SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR
MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS
SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE
BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT
TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE
VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING.
OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD.
THIS AFTERNOON AND TONIGHT...
A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO
THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING
THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL
NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT
500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA.
GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL
BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS
AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE
MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA
AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND
WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST
TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING
THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS
CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE
TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC
EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY
MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY
AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE
DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO
SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH
HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT
FOLLOWS
BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE
SNOW /FOR GOOD FINALLY?/.
ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS
AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING
LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY
SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A
MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE
BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE.
THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE
PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER
MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING
THANKS TO DECENT SNOWFALL RATES AT TIMES.
TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON
AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION
CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS
WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT
/CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE.
TUESDAY THROUGH THURSDAY...
NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A
CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE
850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE
DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO
MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST
AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR
MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES
GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT
ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES
SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN
ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW
AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT
TIME
FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY
WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING
THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY.
FRIDAY AND BEYOND...
GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN
ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST
INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS
GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH
ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING
LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW GIVEN THE
BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM
A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN
TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND
PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW.
GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE
SOMETIME LATE FRIDAY/THIS WEEKEND.
MTF
&&
.CLIMATE...
625 AM CDT
THE FOLLOWING ARE THE LAST APRIL DATES AND AMOUNTS OF ACCUMULATING
SNOWFALL:
CHICAGO: APRIL 18 2011 (0.6 IN.)
ROCKFORD: APRIL 5 2009 (0.2 IN.)
THE FOLLOWING ARE RECORD LOWS FOR THE MORNING OF APRIL 15TH. THE
CHICAGO ONE IS THE MOST LIKELY IN JEOPARDY.
CHICAGO: 25 (1943)
ROCKFORD: 16 (1928)
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* MVFR CEILINGS...LOWERING BACK TOWARDS LOW END MVFR LATER THIS
AFTERNOON.
* GUSTY NORTH/NORTHWEST WINDS.
* RAIN/SNOW MIX...WITH BETTER SNOW DEVELOPMENT MOVING OVER THE
TERMINAL LATE THIS AFTERNOON INTO THE EARLY EVENING.
* POSSIBLE LAKE EFFECT SNOW SHOWERS LINGERING INTO THE LATE
EVENING.
RODRIGUEZ
//DISCUSSION...UPDATED 18Z...
COMPLEX FORECAST THIS PERIOD AS A WINTRY MIX IS LIKELY THIS
AFTERNOON INTO THE EVENING. LATEST RADAR IMAGERY DEPICTING
CONTINUED LIGHT DEVELOPMENT AT THIS HOUR WITH ALL SNOW BEING
REPORTED ACROSS NORTH/NORTHWEST ILLINOIS...AND THEN A RAIN SNOW
MIX BEING REPORTED OVER AREAS IN NORTHEAST ILLINOIS. THIS LIGHTER
DEVELOPMENT WILL LIKELY CONTINUE THROUGH MID AFTERNOON BEFORE A
HEAVIER/STEADIER BAND OF LIGHT TO MODERATE SNOW MOVES THROUGH LATE
THIS AFTERNOON INTO THE EARL EVENING...WITH ANY AREAS OBSERVING A
RAIN/SNOW MIX OBSERVING A QUICK TRANSITION TO ALL SNOW. VIS AND
CEILINGS WILL LIKELY LOWER UNDER THIS BETTER DEVELOPMENT...WITH
IFR VIS AND LOW END MVFR CEILINGS LIKELY. THIS STEADIER SNOW
SHOULD BEGIN TO SHIFT EAST OF THE TERMINALS LATER THIS
EVENING...BUT WITH LAKE EFFECT DEVELOPMENT POSSIBLY LINGERING
THROUGH THE MIDNIGHT TIME FRAME. CONFIDENCE IS LOW WITH REGARDS TO
LAKE EFFECT SNOW DEVELOPMENT THIS EVENING/TONIGHT...AND WILL NEED
TO MONITOR THIS POSSIBLE DEVELOPMENT. AREAS WILL THEN OBSERVE A
CLEARING TREND OVERNIGHT...WITH VFR CONDITIONS THEN LIKELY
TUESDAY. NORTHERLY WINDS MAY CONTINUE TO VARY BETWEEN NNW AND NNE
OVER THE NEXT SEVERAL HOURS...BUT WITH A TREND TOWARDS NNW. HAVE
CONTINUED TO LOWER SPEEDS/GUSTS THIS AFTERNOON WITH THE HIGHEST
GUSTS OF AROUND 21KT NOW LIKELY EARLY THIS AFTERNOON. NORTHWEST
WINDS WILL PREVAIL TONIGHT INTO TUESDAY...WITH SPEEDS DIMINISHING.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM HIGH CONFIDENCE WITH CEILING TRENDS.
* MEDIUM HIGH CONFIDENCE IN WIND DIRECTION/SPEED.
* MEDIUM HIGH CONFIDENCE WITH RAIN/SNOW AND ALL SNOW TRENDS AND
TIMING.
* LOW CONFIDENCE WITH LAKE EFFECT SNOW SHOWERS.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT...VFR.
WEDNESDAY...VFR.
THURSDAY...VFR.
FRIDAY...CHC RAIN. MVFR/IFR PSBL.
SATURDAY...SLT CHC RAIN. MVFR/IFR PSBL.
SUNDAY...CHC RAIN. MVFR/IFR PSBL.
BMD
&&
.MARINE...
240 AM CDT
LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS
MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE
BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO
PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH
TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR
THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD
DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL
TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING
WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN
ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 4
PM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
103 PM CDT MON APR 14 2014
.DISCUSSION...
1205 PM CDT
CHALLENGING FORECAST CONTINUES THROUGH THE EVENING WITH PRECIP
COVERAGE...INTENSITY...AND TYPE BEING THE MAIN FOCUS. LARGE SCALE
UPPER TROUGH COVERING THE MID SECTION OF THE COUNTRY CONTINUES TO
PIVOT EASTWARD PUSHING COLDER AIR INTO THE REGION. SUBTLE WAVES
TRAVERSING THE FLOW CONTINUE TO WORK WITH COLD ADVECTION TO BRING
PRECIP DEVELOPMENT. SURFACE TEMPS HAVE WARMED CENTRAL AND
SOUTHEAST WHICH IS SUPPORTIVE OF MORE RAIN BUT TEMPERATURES WILL
LIKELY COOL INTO THE AFTERNOON FROM THE NORTHWEST.
THEREFORE...PRECIP TYPE THROUGH EARLY AFTERNOON WILL LIKELY BE
RAIN OR SNOW EXCEPT FOR FAR SOUTHEAST AREAS THAT WOULD SEE
RAIN...THOUGH PRECIP CHANCES ARE LOWER THERE. WATER VAPOR SHOWS A
MORE ORGANIZED SHORTWAVE STARTING TO EJECT NORTHEAST FROM
SOUTHWEST MISSOURI AND EASTERN OKLAHOMA AND KANSAS. THIS WAVE WILL
LIFT INTO THE AREA LATE THIS AFTERNOON INTO THE EARLY EVENING AND
TIGHTEN THE MID LEVEL BAROCLINIC ZONE RESULTING IN INTENSIFYING
FRONTOGENESIS. RADAR MOSAIC SHOWS BANDS OF PRECIP DEVELOPING
NORTHEASTWARD IN CONJUNCTION WITH THIS FEATURE. WILL CONTINUE WITH
THE IDEA OF A MORE FOCUSED PERIOD OF PRECIPITATION LATE THIS
AFTERNOON INTO THE EVENING BUT HAVE TRIED TO REFINE DETAILS. WHILE
PRECIP WILL CONTINUE ON AND OFF THROUGH THE AFTERNOON...HAVE
SLOWED THE PERIOD OF BETTER COVERAGE/INTENSITY SLIGHTLY. FORECAST
SOUNDINGS/CONCEPTUAL MODELS SUPPORT ALL SNOW WITHIN THE MOST
INTENSE BAND THANKS TO WELL ALIGNED ASCENT WITHIN THE SNOW GROWTH
ZONE AND COOLING LOW LEVEL TEMP PROFILES. EXPECT THAT THERE WILL
BE A CORRIDOR OF MODERATE SNOW WITHIN A LARGER AREA OF LESS
INTENSE PRECIP THAT WILL DEVELOP NORTHWARD ALONG A LINE FROM
ROUGHLY CHICAGO TO MENDOTA...THEN PIVOT EASTWARD INTO THE EVENING.
MUCH OF THE EVENING RUSH HOUR IN THE CHICAGO METRO LOOKS TO FALL
INTO THE PERIOD OF MORE INTENSE SNOWFALL...WHICH MAY LAST A FEW
HOURS. THE VORT MAX LIFTS NORTHEAST WHICH MAY BRING A LULL IN THE
PRECIP EARLY THIS EVENING BUT LARGER SCALE FORCING INCREASES TO
THE EAST SO THERE MAY BE RE-INTENSIFICATION OVER NORTHWEST INDIANA
BY MID EVENING BEFORE PRECIP EXITS LATE EVENING. TEMPERATURES
WILL LIKELY COOL INTO THE MID 30S LATER TODAY AND SNOW SHOULD FALL
AT AN INTENSE ENOUGH RATE TO PROVIDE FOR ACCUMULATION ON GRASSY
SURFACES AND SLUSHY ACCUMULATION ON ROADS. WILL CONTINUE WITH THE
IDEA OF AROUND AN INCH OF ACCUMULATION.
MDB
//PREV DISCUSSION...
330 AM CDT
THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY
IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS.
THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST
CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL
BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD
LEVELS TONIGHT.
THIS MORNING...
THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO
EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES
60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE
DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING
NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND
MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET
SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR
MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS
SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE
BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT
TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE
VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING.
OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD.
THIS AFTERNOON AND TONIGHT...
A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO
THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING
THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL
NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT
500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA.
GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL
BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS
AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE
MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA
AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND
WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST
TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING
THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS
CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE
TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC
EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY
MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY
AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE
DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO
SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH
HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT
FOLLOWS
BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE
SNOW /FOR GOOD FINALLY?/.
ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS
AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING
LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY
SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A
MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE
BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE.
THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE
PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER
MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING
THANKS TO DECENT SNOWFALL RATES AT TIMES.
TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON
AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION
CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS
WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT
/CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE.
TUESDAY THROUGH THURSDAY...
NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A
CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE
850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE
DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO
MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST
AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR
MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES
GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT
ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES
SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN
ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW
AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT
TIME
FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY
WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING
THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY.
FRIDAY AND BEYOND...
GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN
ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST
INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS
GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH
ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING
LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW GIVEN THE
BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM
A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN
TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND
PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW.
GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE
SOMETIME LATE FRIDAY/THIS WEEKEND.
MTF
&&
.CLIMATE...
625 AM CDT
THE FOLLOWING ARE THE LAST APRIL DATES AND AMOUNTS OF ACCUMULATING
SNOWFALL:
CHICAGO: APRIL 18 2011 (0.6 IN.)
ROCKFORD: APRIL 5 2009 (0.2 IN.)
THE FOLLOWING ARE RECORD LOWS FOR THE MORNING OF APRIL 15TH. THE
CHICAGO ONE IS THE MOST LIKELY IN JEOPARDY.
CHICAGO: 25 (1943)
ROCKFORD: 16 (1928)
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* MVFR CEILINGS...LOWERING BACK TOWARDS LOW END MVFR LATER THIS
AFTERNOON.
* GUSTY NORTHERLY WINDS.
* RAIN/SNOW MIX EARLY THIS AFTERNOON...WITH BETTER SNOW
DEVELOPMENT MOVING OVER THE TERMINAL LATE THIS AFTERNOON INTO
THE EARLY EVENING.
* POSSIBLE LAKE EFFECT SNOW SHOWERS LINGERING INTO THE LATE
EVENING.
RODRIGUEZ
//DISCUSSION...UPDATED 18Z...
COMPLEX FORECAST THIS PERIOD AS A WINTRY MIX IS LIKELY THIS
AFTERNOON INTO THE EVENING. LATEST RADAR IMAGERY DEPICTING
CONTINUED LIGHT DEVELOPMENT AT THIS HOUR WITH ALL SNOW BEING
REPORTED ACROSS NORTH/NORTHWEST ILLINOIS...AND THEN A RAIN SNOW
MIX BEING REPORTED OVER AREAS IN NORTHEAST ILLINOIS. THIS LIGHTER
DEVELOPMENT WILL LIKELY CONTINUE THROUGH MID AFTERNOON BEFORE A
HEAVIER/STEADIER BAND OF LIGHT TO MODERATE SNOW MOVES THROUGH LATE
THIS AFTERNOON INTO THE EARL EVENING...WITH ANY AREAS OBSERVING A
RAIN/SNOW MIX OBSERVING A QUICK TRANSITION TO ALL SNOW. VIS AND
CEILINGS WILL LIKELY LOWER UNDER THIS BETTER DEVELOPMENT...WITH
IFR VIS AND LOW END MVFR CEILINGS LIKELY. THIS STEADIER SNOW
SHOULD BEGIN TO SHIFT EAST OF THE TERMINALS LATER THIS
EVENING...BUT WITH LAKE EFFECT DEVELOPMENT POSSIBLY LINGERING
THROUGH THE MIDNIGHT TIME FRAME. CONFIDENCE IS LOW WITH REGARDS TO
LAKE EFFECT SNOW DEVELOPMENT THIS EVENING/TONIGHT...AND WILL NEED
TO MONITOR THIS POSSIBLE DEVELOPMENT. AREAS WILL THEN OBSERVE A
CLEARING TREND OVERNIGHT...WITH VFR CONDITIONS THEN LIKELY
TUESDAY. NORTHERLY WINDS MAY CONTINUE TO VARY BETWEEN NNW AND NNE
OVER THE NEXT SEVERAL HOURS...BUT WITH A TREND TOWARDS NNW. HAVE
CONTINUED TO LOWER SPEEDS/GUSTS THIS AFTERNOON WITH THE HIGHEST
GUSTS OF AROUND 21KT NOW LIKELY EARLY THIS AFTERNOON. NORTHWEST
WINDS WILL PREVAIL TONIGHT INTO TUESDAY...WITH SPEEDS DIMINISHING.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM HIGH CONFIDENCE WITH CEILING TRENDS.
* MEDIUM HIGH CONFIDENCE IN WIND DIRECTION/SPEED.
* MEDIUM HIGH CONFIDENCE WITH RAIN/SNOW AND ALL SNOW TRENDS AND
TIMING.
* LOW CONFIDENCE WITH LAKE EFFECT SNOW SHOWERS.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT...VFR.
WEDNESDAY...VFR.
THURSDAY...VFR.
FRIDAY...CHC RAIN. MVFR/IFR PSBL.
SATURDAY...SLT CHC RAIN. MVFR/IFR PSBL.
SUNDAY...CHC RAIN. MVFR/IFR PSBL.
BMD
&&
.MARINE...
240 AM CDT
LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS
MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE
BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO
PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH
TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR
THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD
DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL
TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING
WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN
ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 4
PM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1210 PM CDT MON APR 14 2014
.DISCUSSION...
1205 PM CDT
CHALLENGING FORECAST CONTINUES THROUGH THE EVENING WITH PRECIP
COVERAGE...INTENSITY...AND TYPE BEING THE MAIN FOCUS. LARGE SCALE
UPPER TROUGH COVERING THE MID SECTION OF THE COUNTRY CONTINUES TO
PIVOT EASTWARD PUSHING COLDER AIR INTO THE REGION. SUBTLE WAVES
TRAVERSING THE FLOW CONTINUE TO WORK WITH COLD ADVECTION TO BRING
PRECIP DEVELOPMENT. SURFACE TEMPS HAVE WARMED CENTRAL AND
SOUTHEAST WHICH IS SUPPORTIVE OF MORE RAIN BUT TEMPERATURES WILL
LIKELY COOL INTO THE AFTERNOON FROM THE NORTHWEST.
THEREFORE...PRECIP TYPE THROUGH EARLY AFTERNOON WILL LIKELY BE
RAIN OR SNOW EXCEPT FOR FAR SOUTHEAST AREAS THAT WOULD SEE
RAIN...THOUGH PRECIP CHANCES ARE LOWER THERE. WATER VAPOR SHOWS A
MORE ORGANIZED SHORTWAVE STARTING TO EJECT NORTHEAST FROM
SOUTHWEST MISSOURI AND EASTERN OKLAHOMA AND KANSAS. THIS WAVE WILL
LIFT INTO THE AREA LATE THIS AFTERNOON INTO THE EARLY EVENING AND
TIGHTEN THE MID LEVEL BAROCLINIC ZONE RESULTING IN INTENSIFYING
FRONTOGENESIS. RADAR MOSAIC SHOWS BANDS OF PRECIP DEVELOPING
NORTHEASTWARD IN CONJUNCTION WITH THIS FEATURE. WILL CONTINUE WITH
THE IDEA OF A MORE FOCUSED PERIOD OF PRECIPITATION LATE THIS
AFTERNOON INTO THE EVENING BUT HAVE TRIED TO REFINE DETAILS. WHILE
PRECIP WILL CONTINUE ON AND OFF THROUGH THE AFTERNOON...HAVE
SLOWED THE PERIOD OF BETTER COVERAGE/INTENSITY SLIGHTLY. FORECAST
SOUNDINGS/CONCEPTUAL MODELS SUPPORT ALL SNOW WITHIN THE MOST
INTENSE BAND THANKS TO WELL ALIGNED ASCENT WITHIN THE SNOW GROWTH
ZONE AND COOLING LOW LEVEL TEMP PROFILES. EXPECT THAT THERE WILL
BE A CORRIDOR OF MODERATE SNOW WITHIN A LARGER AREA OF LESS
INTENSE PRECIP THAT WILL DEVELOP NORTHWARD ALONG A LINE FROM
ROUGHLY CHICAGO TO MENDOTA...THEN PIVOT EASTWARD INTO THE EVENING.
MUCH OF THE EVENING RUSH HOUR IN THE CHICAGO METRO LOOKS TO FALL
INTO THE PERIOD OF MORE INTENSE SNOWFALL...WHICH MAY LAST A FEW
HOURS. THE VORT MAX LIFTS NORTHEAST WHICH MAY BRING A LULL IN THE
PRECIP EARLY THIS EVENING BUT LARGER SCALE FORCING INCREASES TO
THE EAST SO THERE MAY BE RE-INTENSIFICATION OVER NORTHWEST INDIANA
BY MID EVENING BEFORE PRECIP EXITS LATE EVENING. TEMPERATURES
WILL LIKELY COOL INTO THE MID 30S LATER TODAY AND SNOW SHOULD FALL
AT AN INTENSE ENOUGH RATE TO PROVIDE FOR ACCUMULATION ON GRASSY
SURFACES AND SLUSHY ACCUMULATION ON ROADS. WILL CONTINUE WITH THE
IDEA OF AROUND AN INCH OF ACCUMULATION.
MDB
&&
.PREV DISCUSSION...
330 AM CDT
THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY
IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS.
THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST
CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL
BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD
LEVELS TONIGHT.
THIS MORNING...
THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO
EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES
60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE
DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING
NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND
MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET
SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR
MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS
SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE
BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT
TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE
VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING.
OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD.
THIS AFTERNOON AND TONIGHT...
A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO
THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING
THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL
NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT
500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA.
GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL
BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS
AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE
MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA
AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND
WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST
TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING
THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS
CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE
TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC
EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY
MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY
AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE
DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO
SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH
HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT
FOLLOWS
BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE
SNOW /FOR GOOD FINALLY?/.
ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS
AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING
LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY
SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A
MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE
BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE.
THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE
PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER
MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING
THANKS TO DECENT SNOWFALL RATES AT TIMES.
TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON
AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION
CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS
WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT
/CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE.
TUESDAY THROUGH THURSDAY...
NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A
CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE
850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE
DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO
MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST
AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR
MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES
GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT
ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES
SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN
ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW
AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT
TIME
FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY
WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING
THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY.
FRIDAY AND BEYOND...
GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN
ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST
INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS
GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH
ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING
LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW GIVEN THE
BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM
A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN
TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND
PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW.
GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE
SOMETIME LATE FRIDAY/THIS WEEKEND.
MTF
&&
.CLIMATE...
625 AM CDT
THE FOLLOWING ARE THE LAST APRIL DATES AND AMOUNTS OF ACCUMULATING
SNOWFALL:
CHICAGO: APRIL 18 2011 (0.6 IN.)
ROCKFORD: APRIL 5 2009 (0.2 IN.)
THE FOLLOWING ARE RECORD LOWS FOR THE MORNING OF APRIL 15TH. THE
CHICAGO ONE IS THE MOST LIKELY IN JEOPARDY.
CHICAGO: 25 (1943)
ROCKFORD: 16 (1928)
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* MVFR CIGS...LOWERING BACK TOWARDS LOW END MVFR LATER THIS
AFTERNOON.
* GUSTY N WINDS THROUGH THE DAY...POSSIBLY TURNING NNE BY EARLY
AFTERNOON.
* SNOW OVERSPREADING THE TERMINALS MID AFTERNOON WITH MINOR
ACCUMULATIONS.
BMD
//DISCUSSION...UPDATED 12Z...
A COLD FRONT IS WORKING ACROSS NORTHEASTERN ILLINOIS EARLY THIS
MORNING WITH WINDS TURNING SHARPLY TO THE NNW WITH GUSTS TO AROUND
30 KT. AREA OBSERVATIONS SHOW A NARROW CORRIDOR OF IFR CIGS IN THE
VICINITY OF THE FRONT...WHICH HAS BEEN SHRINKING OVERNIGHT WITH
PRIMARILY MVFR CIGS EXPECTED THIS MORNING. PRECIP HAS ALSO DWINDLED
AND EXPECTED A COUPLE HOURS OF LIGHT RAIN/DRIZZLE EARLY THIS MORNING
THEN DRY CONDITIONS SHOULD PREVAIL THROUGH AROUND MID AFTERNOON. AT
THAT TIME...AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA
WITH PRECIP OVERSPREADING THE AREA FROM THE SOUTHWEST. RFD MAY BE
CLIPPED BY THIS PRECIP...BUT THE CHICAGO TERMINALS ARE EXPECTED TO
TAKE A MORE DIRECT SHOT. AT THE ONSET...TEMPERATURES MAY BE WARM
ENOUGH FOR A MIX OF RAIN AND SNOW...PARTICULARLY AT MDW AND
GYY...BUT THE COLUMN WILL COOL AND EXPECT A TRANSITION TO ALL SNOW
WITH MINOR ACCUMULATIONS POSSIBLE...ESPECIALLY ON GRASSY SURFACES...
OF UP TO AROUND AND INCH. WINDS SHOULD PRIMARILY REMAIN IN THE
330-360 DIRECTION TODAY WITH GUSTS AROUND 30 KT THIS MORNING VERY
SLOWLY TAPERING THROUGH THE DAY.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM HIGH CONFIDENCE WITH CIGS.
* MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED.
* MEDIUM-HIGH CONFIDENCE IN SNOW TIMING THIS AFTERNOON.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT...VFR.
WEDNESDAY...VFR.
THURSDAY...VFR.
FRIDAY...CHC RAIN. MVFR/IFR PSBL.
SATURDAY...SLT CHC RAIN. MVFR/IFR PSBL.
SUNDAY...CHC RAIN. MVFR/IFR PSBL.
BMD
&&
.MARINE...
240 AM CDT
LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS
MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE
BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO
PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH
TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR
THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD
DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL
TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING
WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN
ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 4
PM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1148 AM CDT MON APR 14 2014
.DISCUSSION...
330 AM CDT
THE INFAMOUS WINTER 2013-2014 BEGAN IN OCTOBER WITH SNOW AND TODAY
IT WANTS TO MAKE SURE IT INCLUDES APRIL TO ENCOMPASS SEVEN MONTHS.
THIS UNFRIENDLY VERY LATE VISIT FROM WINTER WAS THE PRIMARY FORECAST
CHALLENGE...ALONG WITH TEMPERATURES THROUGHOUT THE WEEK AS WE WILL
BE WELL BELOW NORMAL TO START THIS WEEK...POTENTIALLY TO RECORD
LEVELS TONIGHT.
THIS MORNING...
THE 995MB SURFACE LOW IS PASSING OVER THE NORTH METRO OF CHICAGO
EARLY THIS MORNING AND 30 MILES EITHER SIDE OF ITS PATH SEPARATES
60S AND CONVECTIVE RAIN SHOWERS AND 30S AND DEFORMATION SNOW. THE
DEEPENING AND CLASSIC LOOKING UPPER WAVE WITH THIS IS ADVANCING
NORTHEAST FROM SOUTHWEST WI AND ITS DEFORMATION AND WRAPAROUND
MOISTURE WILL ONLY GRAZE THE AREA THIS MORNING. WHILE A MIX WITH WET
SNOW IS PROBABLE OVER PARTS OF NORTH CENTRAL IL...THE FORCING FOR
MODEST SNOW RATES IS LIKELY TO REMAIN TO THE NORTH IN THE A.M. HOURS
SO NOT EXPECTING ANY ACCUMULATIONS PRIOR TO NOON. WINDS ON THE
BACKSIDE OF THE LOW THIS MORNING LOOK TO GUST TO AROUND 40 MPH AT
TIMES...WHICH BESIDES ADDING QUITE A CHILL TO THE AIR...MAY REDUCE
VISIBILITY UP BY ROCKFORD IF SNOW CAN MATERIALIZE THIS MORNING.
OTHERWISE THOUGH...IMPACTS LOOK MINOR DURING THIS PERIOD.
THIS AFTERNOON AND TONIGHT...
A SECOND WELL-DEFINED UPPER CIRCULATION IS ADVANCING EASTWARD INTO
THE CENTRAL PLAINS EARLY THIS MORNING. THIS IS BASICALLY ROUNDING
THE BASE OF WHAT REALLY IS A MASSIVE LONGWAVE TROUGH ACROSS CENTRAL
NORTH AMERICA...WITH AN IMPRESSIVE JANUARY-LIKE -40C OBSERVED AT
500MB LAST NIGHT ALL THE WAY SOUTH TO CYQD IN SOUTHERN MANITOBA.
GIVEN THE UPPER FLOW...PV ANOMALY EVOLUTION...AND MID-LEVEL
BAROCLINICITY...THIS WAVE IS FORECAST TO TURN MORE NORTHEAST THIS
AFTERNOON AND ADVANCE INTO CENTRAL AND NORTHERN IL/IN DURING THE
MID-AFTERNOON INTO MID-EVE. THIS WILL BRING WITH IT FOCUSED OMEGA
AND FRONTOGENETIC SUPPORTED UPWARD MOTION DURING THAT PERIOD AND
WOULD EXPECT TO SEE MODERATE PRECIPITATION DEVELOPING FROM SOUTHWEST
TO NORTHEAST ACROSS THE HEART OF THE FORECAST AREA...LIKELY REACHING
THE CHICAGO AREA DURING THE 3-6 PM TIME. SO HAVE BUMPED UP POPS
CONSIDERABLY. IN ADDITION...THE MID-LEVEL TEMPERATURES WILL CONTINUE
TO COOL WITH THE FEATURE AND THE LOWER LEVELS THROUGH DIABATIC
EFFECTS. ITS QUITE RARE TO SEE SNOW HERE DURING APRIL /ESPECIALLY
MID-APRIL/ AFTERNOONS...BUT DO SEE PRECIPITATION STRUGGLING TO STAY
AS RAIN GIVEN RAP AND NAM FORECAST THERMAL PROFILES AND JUST THE
DEGREE OF FORCING. SO A QUICK TRANSITION TO A WET SNOW FROM NORTH TO
SOUTH ACROSS THE CHICAGO METRO AREA IS FAVORED DURING THE RUSH
HOUR...AND PROBABLY THE FIRST HALF AT THAT. SUPPRESSION ALOFT
FOLLOWS
BEHIND THE UPPER WAVE LATE THIS EVE INTO OVERNIGHT AND WILL END THE
SNOW /FOR GOOD FINALLY?/.
ANY INITIAL SNOW WILL STRUGGLE TO STICK WITH 4-INCH SOIL TEMPS
AROUND 50 DEGREES AND THE WET GROUND IN PLACES...BUT THE FORCING
LIKELY IS TO WIN OUT FOR A LIGHT COATING ESPECIALLY ON GRASSY
SURFACES. THIS IS PRESENTLY MOST FAVORED ALONG AND SOUTH OF A
MENDOTA TO CHICAGO LINE...AS THAT IS THE AREA THAT LOOKS TO HAVE THE
BEST FORCING AS THE TEMPERATURES COOL LATE IN THE DAY AND THIS EVE.
THERE IS UNCERTAINTY WITH THIS PLACEMENT THOUGH...AS SOME MESOSCALE
PARAMETERS ARE AT PLAY. ACCUMULATION AROUND AN INCH TO A LITTLE OVER
MAY OCCUR IN THE AREA THAT DOES END UP SEEING THE BETTER FORCING
THANKS TO DECENT SNOWFALL RATES AT TIMES.
TEMPERATURES WILL HOLD FLAT-LINE AND EVEN DROP DURING THE AFTERNOON
AS PRECIPITATION EVOLVES INTO THE REGION. COLD AIR ADVECTION
CONTINUES TONIGHT WITH 850MB TEMPS DROPPING TO THE -10C ARENA. THIS
WILL SUPPORT CHICAGO CLOSING IN ON A RECORD LOW FOR TONIGHT
/CALENDAR DAY OF APRIL 15/. SEE CLIMATE SECTION BELOW FOR MORE.
TUESDAY THROUGH THURSDAY...
NOT TOO MANY CHANGES MADE TO THIS PERIOD WHICH LOOKS MAINLY QUIET. A
CHILLY TUESDAY IS EXPECTED WITH THE LOW STARTING POINT AND THE
850-925MB THERMAL TROUGH OVER US IN THE MORNING. A LAKE BREEZE
DEVELOPING THAT AFTERNOON WILL NOT HELP MATTERS EITHER. UPPER 30S TO
MID 40S ARE EXPECTED FROM NEAR THE LAKE TO THE REST OF THE FORECAST
AREA ON TUESDAY AFTERNOON. UNCERTAINTY EXISTS ON CLOUD COVER FOR
MUCH OF THIS TIME RANGE AND THAT WILL OF COURSE IMPACT TEMPERATURES
GREATLY. THIS INCLUDES HIGH CLOUDS TUESDAY NIGHT WHICH COULD PREVENT
ANOTHER CHILLY NIGHT IN THE 20S...AND HAVE INCHED UP FORECAST VALUES
SOME FAVORING A LITTLE MORE CLOUD COVER AT THIS TIME. IN
ADDITION...THURSDAY INTO THURSDAY NIGHT LOOKS TO HAVE SOUTHERLY FLOW
AND THERE ARE INDICATIONS OF LOW CLOUDS MOVING NORTH DURING THAT
TIME
FRAME. WILL NEED TO WAIT TO THAT PERIOD GETS CLOSER TO GET TOO FANCY
WITH TEMPERATURES BUT HAVE GONE WITH A BLEND OF GUIDANCE INCLUDING
THE PREVIOUS FORECAST AT THIS TIME FOR TEMPS DURING THURSDAY.
FRIDAY AND BEYOND...
GIVEN A MASSIVE UPPER RIDGE OVER THE WESTERN TO NORTHERN
ATLANTIC...ANY SHARP ADVANCEMENT OF AN UPPER RIDGE FROM THE WEST
INTO OUR AREA LOOKS TO BE HALTED/SLOWED. WE WILL BUILD HEIGHTS
GRADUALLY THURSDAY BUT MODEL GUIDANCE IS IN DECENT AGREEMENT WITH
ADVANCING A PACIFIC SYSTEM INTO THE REGION BY FRIDAY AND PRODUCING
LIKELY RAIN IN THE GENERAL REGION. THIS COULD SLOW GIVEN THE
BACKED UP FLOW TO OUR EAST...AND HAVE TAKEN THAT INTO ACCOUNT FROM
A SMART BLEND OF GUIDANCE POPS...SLOWING THEM SOMEWHAT. ONCE AGAIN
TEMPERATURES ON FRIDAY DEPEND HEAVILY ON WHETHER OR NOT CLOUDS AND
PRECIP ARE AS PROLIFIC AS MOST GUIDANCE IS INDICATING NOW.
GRADUALLY BUILDING HEIGHTS SHOULD FOLLOW THAT SYSTEM DEPARTURE
SOMETIME LATE FRIDAY/THIS WEEKEND.
MTF
&&
.CLIMATE...
625 AM CDT
THE FOLLOWING ARE THE LAST APRIL DATES AND AMOUNTS OF ACCUMULATING
SNOWFALL:
CHICAGO: APRIL 18 2011 (0.6 IN.)
ROCKFORD: APRIL 5 2009 (0.2 IN.)
THE FOLLOWING ARE RECORD LOWS FOR THE MORNING OF APRIL 15TH. THE
CHICAGO ONE IS THE MOST LIKELY IN JEOPARDY.
CHICAGO: 25 (1943)
ROCKFORD: 16 (1928)
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* MVFR CIGS...LOWERING BACK TOWARDS LOW END MVFR LATER THIS
AFTERNOON.
* GUSTY N WINDS THROUGH THE DAY...POSSIBLY TURNING NNE BY EARLY
AFTERNOON.
* SNOW OVERSPREADING THE TERMINALS MID AFTERNOON WITH MINOR
ACCUMULATIONS.
BMD
//DISCUSSION...UPDATED 12Z...
A COLD FRONT IS WORKING ACROSS NORTHEASTERN ILLINOIS EARLY THIS
MORNING WITH WINDS TURNING SHARPLY TO THE NNW WITH GUSTS TO AROUND
30 KT. AREA OBSERVATIONS SHOW A NARROW CORRIDOR OF IFR CIGS IN THE
VICINITY OF THE FRONT...WHICH HAS BEEN SHRINKING OVERNIGHT WITH
PRIMARILY MVFR CIGS EXPECTED THIS MORNING. PRECIP HAS ALSO DWINDLED
AND EXPECTED A COUPLE HOURS OF LIGHT RAIN/DRIZZLE EARLY THIS MORNING
THEN DRY CONDITIONS SHOULD PREVAIL THROUGH AROUND MID AFTERNOON. AT
THAT TIME...AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA
WITH PRECIP OVERSPREADING THE AREA FROM THE SOUTHWEST. RFD MAY BE
CLIPPED BY THIS PRECIP...BUT THE CHICAGO TERMINALS ARE EXPECTED TO
TAKE A MORE DIRECT SHOT. AT THE ONSET...TEMPERATURES MAY BE WARM
ENOUGH FOR A MIX OF RAIN AND SNOW...PARTICULARLY AT MDW AND
GYY...BUT THE COLUMN WILL COOL AND EXPECT A TRANSITION TO ALL SNOW
WITH MINOR ACCUMULATIONS POSSIBLE...ESPECIALLY ON GRASSY SURFACES...
OF UP TO AROUND AND INCH. WINDS SHOULD PRIMARILY REMAIN IN THE
330-360 DIRECTION TODAY WITH GUSTS AROUND 30 KT THIS MORNING VERY
SLOWLY TAPERING THROUGH THE DAY.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM HIGH CONFIDENCE WITH CIGS.
* MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED.
* MEDIUM-HIGH CONFIDENCE IN SNOW TIMING THIS AFTERNOON.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT...VFR.
WEDNESDAY...VFR.
THURSDAY...VFR.
FRIDAY...CHC RAIN. MVFR/IFR PSBL.
SATURDAY...SLT CHC RAIN. MVFR/IFR PSBL.
SUNDAY...CHC RAIN. MVFR/IFR PSBL.
BMD
&&
.MARINE...
240 AM CDT
LOW PRESSURE IS MOVING ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS
MORNING WITH GALE FORCE NORTHERLY WINDS OVERSPREADING THE LAKE
BEHIND THE LOW AS IT BEGINS TO DEPART EAST. GALES ARE EXPECTED TO
PERSIST THROUGH THE AFTERNOON...THEN SHOULD VERY GRADUALLY DIMINISH
TO AROUND 30 KT THIS EVENING AND TONIGHT. FOG THAT WAS IN PLACE NEAR
THE FRONTAL BOUNDARY ACROSS FAR SOUTHERN LAKE MICHIGAN SHOULD
DIMINISH AS THE NORTHERLY WINDS OVERSPREAD THE LAKE. RIDGING WILL
TRANSLATE ACROSS LAKE MICHIGAN LATE IN THE DAY TUESDAY ALLOWING
WINDS TO BRIEFLY SUBSIDE...BUT SOUTH/SOUTHEAST WINDS PICK UP AGAIN
ON WEDNESDAY AS ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 4
PM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS GOODLAND KS
310 PM MDT MON APR 14 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 1252 PM MDT MON APR 14 2014
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW TROUGH
EXTENDING FROM GREAT LAKES ACROSS THE CENTRAL/SOUTHERN PLAINS AND
RIDGE BUILDING OVER WESTERN US. AT THE SURFACE HIGH PRESSURE IS IN
PLACE ACROSS EASTERN COLORADO/WESTERN KS WITH N-NW GRADIENT OVER
KS/NE SUPPORTING GUSTY WINDS OVER OUR CWA. SNOW PACK HAS RETREATED
OVER MUCH OF OUR CWA...WHILE VIS SATELLITE INDICATES IT HOLDING ON
OVER PARTS OF NE COLORADO AND ALONG KS/NE STATE LINE WHERE AROUND
INCHES OF SNOW FELL MONDAY AND MONDAY NIGHT.
ON THE BACK SIDE OF DEPARTING UPPER LEVEL TROUGH H3 JET STEAM IS
MOVING ACROSS NORTHERN PLAINS. STEEP LOW/MID LEVEL LAPSE RATES HAVE
DEVELOPED WITH SHALLOW COOL LAYER AND DAYTIME HEATING AND HAS LED TO
CU FIELD DEVELOPING OVER THE SOUTHERN PART OF OUR CWA. AS NOSE OF JET
MOVES ACROSS CENTRAL NEBRASKA THERE MAY BE ENOUGH FORCING ALONG WITH
THIS WEAKLY UNSTABLE MID LAYER FOR A FEW SPRINKLES TO MOVE INTO THE
NORTHEAST CORNER OF OUR CWA...OTHERWISE WE ARE ONLY LOOKING AT A
PERIOD OF MID LEVEL CU OVER OUR CWA THIS AFTERNOON. IF THERE IS A
BETTER SHOWER WE COULD SEE A FLURRY INSTEAD OF SPRINKLE
THROUGH...BUT I DIDN`T SEE A REASON TO GET THAT CUTE CONSIDERING
CONFIDENCE IS ALREADY LOW ON PRECIP REACHING THE GROUND IN OUR NE
CWA.
ANOTHER HARD FREEZE IS EXPECTED TONIGHT...THOUGH THERE WILL BE SOME
MODERATION OF THE AIR MASS ALOFT AS HIGH PRESSURE SHIFTS EAST AND
W-SW WINDS DEVELOP LATE TONIGHT.
MONDAY...CONTINUE MODERATION OF THE AIR MASS IS EXPECTED WITH
DAYTIME HIGHS REACHING SEASONAL VALUES IN THE 60S ACROSS THE CWA.
SNOW PACK COULD STILL IMPACT LOCATIONS IN THE NORTH...HOWEVER WITH
SW WINDS COMING FROM SNOW FREE LOCATIONS WE SHOULD SEE A QUICK
MELTING OF SNOW. MAIN CONCERN FOR MONDAY WILL BE POTENTIAL FOR RED
FLAG CONDITIONS WITH WINDY CONDITIONS DEVELOPING EARLY IN THE WEST
AND GOOD MIXING SUPPORTING LOWER TD VALUES ACROSS THE SOUTH.
MODEL OUTPUT GENERALLY SUPPORTS A DECREASING TREND IN THE WEST IN
THE AFTERNOON AS GRADIENT SHIFTS EAST...SO THERE MAY ONLY BE A
SMALL WINDOW FOR WIND/RH CROSSOVER. OF COURSE THERE IS ALSO THE
QUESTION OF WHETHER FUELS WILL BE CURED AFTER RECENT PRECIP
(ESPECIALLY OVER LOCATIONS WITH LINGERING SNOW PACK). WITH TOO
MUCH UNCERTAINTY I DECIDED AGAINST ISSUANCE OF FIRE WEATHER WATCH
AT THIS TIME.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 237 PM MDT MON APR 14 2014
MODEL SOLUTIONS REMAIN IN CLOSE AGREEMENT THROUGH THE END OF THE
WORK WEEK AND THEN BEGIN TO DIVERGE THROUGH THE WEEKEND AS AN
UPPER TROUGH MOVES ACROSS THE NORTHERN PLAINS IN THE NORTHERN
BRANCH OF THE UPPER FLOW AND A SHORT WAVE TROUGH EMBEDDED IN THE
SOUTHERLY BRANCH TRIES TO COME INTO PHASE WITH THE NORTHERLY
BRANCH.
THE GFS REMAINS THE MORE PROGRESSIVE SOLUTION WHILE THE ECMWF
LAGS BEHIND NEARLY 24 HOURS. THIS IS PROVING TO BE TROUBLESOME
WITH THE TIMING OF THE PRECIPITATION THAT IS POSSIBLE BETWEEN A
LATE FRIDAY TO LATE SATURDAY TIME FRAME. HAVE GONE WITH SOME KIND
OF BLENDED COMPROMISE SOLUTION FOR THE FRIDAY THROUGH SUNDAY TIME
PERIOD WITH RAIN SHOWERS TRANSITIONING TO A FEW THUNDERSTORMS AND
BACK TO RAIN SHOWERS ON SATURDAY AND SATURDAY NIGHT. EXPECT DRY
AND WARMER CONDITIONS THROUGH THE REMAINDER OF THE WEEKEND INTO
THE BEGINNING OF NEXT WEEK AS A LARGE RIDGE AMPLIFIES OVER THE
WESTERN UNITED STATES AND MOVES EAST OVER THE ROCKIES AND HIGH
PLAINS REGION.
BACKTRACKING TO THE MID-WEEK SYSTEM...
EXPECT RAIN TO DEVELOP EAST OF THE ROCKIES LATE WEDNESDAY AND
TRANSITION TO SNOW AS IT SPREADS ACROSS THE FORECAST AREA
WEDNESDAY NIGHT. EXPECT A TRANSITION BACK TO RAIN DURING THE DAY
ON THURSDAY...BUT MAY END UP STAYING MORE SNOW THROUGH THURSDAY
MORNING IF TEMPERATURES REMAIN COLDER AND WET BULB ZERO
TEMPERATURES ARE COLDER AS THEY WERE WITH THE LAST SYSTEM THAT
DEPOSITED SNOW ACROSS THE FORECAST AREA. EXPECT PRECIPITATION TO
END FROM WEST TO EAST ACROSS THE FORECAST AREA LATE IN THE DAY ON
THURSDAY. TEMPS WILL WARM BRIEFLY ON FRIDAY AND SATURDAY AHEAD OF
THE NEXT SYSTEM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1133 AM MDT MON APR 14 2014
LAYER OF CU 3000-5000KFT AGL HAS DEVELOPED NEAR GLD WITH WEAKLY
UNSTABLE LAYER ASSOCIATED WITH DAYTIME HEATING...AND A SECOND AREA
OF CU ASSOCIATED THE WEAK UPPER LEVEL DISTURBANCE WILL MOVE OUT
OF NEBRASKA OVER KMCK. CONDITIONS ARE EXPECTED TO REMAIN VFR WITH
THESE CLOUDS CLEARING AROUND 00Z WITH LOSS OF DAYTIME HEATING.
NW WINDS GUSTING TO 25KT AT BOTH TERMINALS WILL DIMINISH AROUND
SUNSET. WINDS SHOULD SHIFT TO THE WEST THEN SOUTHWEST WITH LEE
TROUGH BEGINNING TO BUILD OVERNIGHT...THEN INCREASE FROM THE WEST
TUESDAY MORNING. EXPECT GUSTS AT KGLD AROUND SUNRISE TUESDAY TO
25KT...POSSIBLY HIGHER. AT KMCK...WINDS WILL LIKELY INCREASE
OUTSIDE THE CURRENT TAF PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1254 PM MDT MON APR 14 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 1252 PM MDT MON APR 14 2014
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW TROUGH
EXTENDING FROM GREAT LAKES ACROSS THE CENTRAL/SOUTHERN PLAINS AND
RIDGE BUILDING OVER WESTERN US. AT THE SURFACE HIGH PRESSURE IS IN
PLACE ACROSS EASTERN COLORADO/WESTERN KS WITH N-NW GRADIENT OVER
KS/NE SUPPORTING GUSTY WINDS OVER OUR CWA. SNOW PACK HAS RETREATED
OVER MUCH OF OUR CWA...WHILE VIS SATELLITE INDICATES IT HOLDING ON
OVER PARTS OF NE COLORADO AND ALONG KS/NE STATE LINE WHERE AROUND
INCHES OF SNOW FELL MONDAY AND MONDAY NIGHT.
ON THE BACK SIDE OF DEPARTING UPPER LEVEL TROUGH H3 JET STEAM IS
MOVING ACROSS NORTHERN PLAINS. STEEP LOW/MID LEVEL LAPSE RATES HAVE
DEVELOPED WITH SHALLOW COOL LAYER AND DAYTIME HEATING AND HAS LED TO
CU FIELD DEVELOPING OVER THE SOUTHERN PART OF OUR CWA. AS NOSE OF JET
MOVES ACROSS CENTRAL NEBRASKA THERE MAY BE ENOUGH FORCING ALONG WITH
THIS WEAKLY UNSTABLE MID LAYER FOR A FEW SPRINKLES TO MOVE INTO THE
NORTHEAST CORNER OF OUR CWA...OTHERWISE WE ARE ONLY LOOKING AT A
PERIOD OF MID LEVEL CU OVER OUR CWA THIS AFTERNOON. IF THERE IS A
BETTER SHOWER WE COULD SEE A FLURRY INSTEAD OF SPRINKLE
THROUGH...BUT I DIDN`T SEE A REASON TO GET THAT CUTE CONSIDERING
CONFIDENCE IS ALREADY LOW ON PRECIP REACHING THE GROUND IN OUR NE
CWA.
ANOTHER HARD FREEZE IS EXPECTED TONIGHT...THOUGH THERE WILL BE SOME
MODERATION OF THE AIR MASS ALOFT AS HIGH PRESSURE SHIFTS EAST AND
W-SW WINDS DEVELOP LATE TONIGHT.
MONDAY...CONTINUE MODERATION OF THE AIR MASS IS EXPECTED WITH
DAYTIME HIGHS REACHING SEASONAL VALUES IN THE 60S ACROSS THE CWA.
SNOW PACK COULD STILL IMPACT LOCATIONS IN THE NORTH...HOWEVER WITH
SW WINDS COMING FROM SNOW FREE LOCATIONS WE SHOULD SEE A QUICK
MELTING OF SNOW. MAIN CONCERN FOR MONDAY WILL BE POTENTIAL FOR RED
FLAG CONDITIONS WITH WINDY CONDITIONS DEVELOPING EARLY IN THE WEST
AND GOOD MIXING SUPPORTING LOWER TD VALUES ACROSS THE SOUTH.
MODEL OUTPUT GENERALLY SUPPORTS A DECREASING TREND IN THE WEST IN
THE AFTERNOON AS GRADIENT SHIFTS EAST...SO THERE MAY ONLY BE A
SMALL WINDOW FOR WIND/RH CROSSOVER. OF COURSE THERE IS ALSO THE
QUESTION OF WHETHER FUELS WILL BE CURED AFTER RECENT PRECIP
(ESPECIALLY OVER LOCATIONS WITH LINGERING SNOW PACK). WITH TOO
MUCH UNCERTAINTY I DECIDED AGAINST ISSUANCE OF FIRE WEATHER WATCH
AT THIS TIME.
.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 242 AM MDT MON APR 14 2014
THE THURSDAY THROUGH SUNDAY PERIOD WILL START OUT WITH AN UPPER
LEVEL TROUGH OVER THE TRI-STATE AREA. THE BEST CHANCES LOOK TO BE
OVER THE EASTERN HALF OF THE AREA WHERE THE LOW LEVEL JET WILL BE
AHEAD OF THE MAIN UPPER LEVEL TROUGH. DESPITE HIGH TEMPERATURES
AROUND 40...WET BULB ZERO HEIGHTS INDICATE THE PRECIP. WILL BE
SNOW. THE FAIRLY WARM TEMPERATURES FOR SNOWFALL SHOULD ALLOW THE
SNOW TO BE WETTER THAN NORMAL FOR THE AREA. SOUNDINGS ACROSS THE
AREA DO NOT INDICATE ANY CONVECTIVE INSTABILITY EXCEPT IN THE LOWEST
100 MB OR SO WHICH WOULD KEEP SNOWFALL RATES ON THE LIGHT SIDE. THE
WARM GROUND TEMPERATURES AND LIGHT SNOWFALL RATES SHOULD ALLOW THE
SNOW TO MELT AS IT FALLS SO DO NOT ANTICIPATE MUCH MORE THAN AN INCH
OR SO OF ACCUMULATIONS OVER THE EAST HALF WITH LESS TO THE WEST.
THURSDAY NIGHT MODELS DISAGREE WITH HOW FAST THE TROUGH WILL MOVE
EAST OF THE AREA...BUT GENERALLY AGREE THE TROUGH WILL BE EAST OF
THE AREA BY MIDNIGHT.
BEHIND THE UPPER LEVEL TROUGH A SHORT WAVE RIDGE WILL MOVE OVER THE
AREA...BRINGING A WARM FRONT INTO THE AREA FRIDAY.
OVER THE WEEKEND THE SHORT WAVE RIDGE MOVES EAST WITH A SPLIT UPPER
LEVEL FLOW DEVELOPING BEHIND IT. AN UPPER LEVEL RIDGE WILL BUILD
OVER THE GREAT BASIN WITH A TROUGH ALSO DEEPENING OVER THE DESERT
SOUTHWEST. AHEAD OF THE SPLIT UPPER LEVEL FLOW A SHORT WAVE TROUGH
WILL MOVE ACROSS THE AREA BRINGING A LOW CHANCE FOR SOME RAINFALL
WITH IT. BEHIND THE SHORT WAVE TROUGH A WEAK FRONT WILL MOVE
THROUGH THE AREA.
TEMPERATURES FOR THE PERIOD WILL START OUT BELOW NORMAL THEN WARM TO
20 DEGREES ABOVE NORMAL BY THE START OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1133 AM MDT MON APR 14 2014
LAYER OF CU 3000-5000KFT AGL HAS DEVELOPED NEAR GLD WITH WEAKLY
UNSTABLE LAYER ASSOCIATED WITH DAYTIME HEATING...AND A SECOND AREA
OF CU ASSOCIATED THE WEAK UPPER LEVEL DISTURBANCE WILL MOVE OUT
OF NEBRASKA OVER KMCK. CONDITIONS ARE EXPECTED TO REMAIN VFR WITH
THESE CLOUDS CLEARING AROUND 00Z WITH LOSS OF DAYTIME HEATING.
NW WINDS GUSTING TO 25KT AT BOTH TERMINALS WILL DIMINISH AROUND
SUNSET. WINDS SHOULD SHIFT TO THE WEST THEN SOUTHWEST WITH LEE
TROUGH BEGINNING TO BUILD OVERNIGHT...THEN INCREASE FROM THE WEST
TUESDAY MORNING. EXPECT GUSTS AT KGLD AROUND SUNRISE TUESDAY TO
25KT...POSSIBLY HIGHER. AT KMCK...WINDS WILL LIKELY INCREASE
OUTSIDE THE CURRENT TAF PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JTL
AVIATION...DR
AREA FORECAST DISCUSSION
NWS JACKSON KY
138 PM EDT MON APR 14 2014
.UPDATE...
ISSUED AT 1136 AM EDT MON APR 14 2014
A FEW UPDATES MADE TO THE FORECAST FOR TODAY. BASED ON THE LATEST
SURFACE OBS AND EXPECTED TRENDS...DECIDED TO LOWER TODAYS HOURLY AND
OVERALL HIGH TEMPERATURES BY 3 OR 4 DEGREES ACROSS THE BOARD. WITH
MOIST GROUND...STEADY WINDS...AND PERSISTENT OVERCAST CLOUD
COVER...DID NOT SEEM REASONABLE THAT PREVIOUS IN THE MID TO UPPER 70S
AREA WIDE WERE REACHABLE. THE LATEST RADAR TRENDS AND MODEL
DATA...PARTICULARLY THE HRRR...SEEMED TO SUPPORT THE CURRENT POPS FOR
THE REST OF THE DAY. THE PRECIP CURRENTLY MOVING ACROSS THE AREA
SEEMS TO HAVE A DISTINCT BACK EDGE THAT WILL BE THROUGH OUR AREA IN
THE NEXT FEW HOURS. AFTER THAT IT APPEARS THAT WE WILL SEE A BREAK IN
THE ACTION UNTIL LATER THIS EVENING A COLD FRONT AND UPPER TROUGH
MOVE THROUGH THE AREA. WILL ALSO BE SENDING OUT UPDATED VERSIONS OF
THE LAKE WIND ADVISORY AND FREEZE WATCH. WINDS ACROSS THE AREA SO FAR
TODAY HAVE BEEN MEETING LAKE WIND CRITERIA AND THERE IS NO REASON TO
BELIEVE THIS WILL CEASE TO BE THE CASE THE REST OF THE DAY.
UPDATE ISSUED AT 702 AM EDT MON APR 14 2014
NO UPDATE PLANNED THIS MORNING. LATEST HRRR HAS STUCK TO ITS SCENARIO
TODAY REGARDING SCATTERED LINE OF SHOWERS PUSHING ITS WAY ACROSS THE
AREA TODAY. THESE SHOWERS ARE JUST NOW WORKING INTO THE I-75
CORRIDOR...AND THE CURRENT FORECAST HAS THIS COVERED WELL. NOT SURE
IF WE WILL BE ABLE TO SQUEEZE OUT MUCH LIQUID WITH SUCH DRY AIR
ENTRENCHED ACROSS THE AREA...BUT WE COULD SQUEEZE OUT A HUNDREDTH OR
TWO THROUGH THE MORNING.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT MON APR 14 2014
THERE ARE SEVERAL FEATURES OF INTEREST THIS MORNING UPSTREAM. A WEAK
MID LEVEL TROUGH IS NOW MOVING INTO THE NORTHERN OHIO RIVER VALLEY
WITH A SURFACE LOW PUSHING INTO THE GREAT LAKES REGION. THIS INITIAL
TROUGH HAD BEEN RESPONSIBLE FOR AN ORGANIZED AREA OF SHOWERS AND
STORMS AS IT PUSHED INTO WESTERN KENTUCKY OVERNIGHT. AS THIS
ACTIVITY CONTINUES TO PUSH EAST THIS MORNING IT WILL ENCOUNTER A MUCH
MORE STABLE AND DRY AIR MASS AND WILL QUICKLY WEAKEN. HRRR HAS A GOOD
HANDLE ON THIS AREA OF PRECIPITATION. AS IT REACHES EASTERN
KENTUCKY...IT LOOKS LIKE THE ACTIVITY MAY BECOME MORE SCATTERED AND
EVEN MORE SO AS IT PUSHES FURTHER EAST. WHILE A FASTER ONSET OF
PRECIPITATION LOOKS LIKELY TODAY...IT ALSO LOOKS LIKE ONLY A LIMITED
WINDOW FOR PRECIPITATION THROUGH EARLY AFTERNOON BEFORE WE DRY OUT
AGAIN BY LATE AFTERNOON AND THIS EVENING AS SUBSIDENCE SPREADS BACK
OVER THE AREA AHEAD OF THE NEXT TROUGH. THUS...GOING TO BACK OFF POPS
TO MORE SCATTERED COVERAGE TODAY AS MANY AREAS...ESPECIALLY IN THE
EAST MAY NOT MEASURE TODAY OR WILL LIKELY SEE VERY LIGHT RAINFALL.
WINDS ARE THE OTHER CONCERN FOR TODAY AS WINDS ARE ALREADY GUSTING UP
TO 30 MPH THIS MORNING. WITH THE WEAKENING SHOWERS SPREADING INTO THE
AREA...WE MAY TAP INTO SOME HIGHER WINDS ALOFT WITH 40 KNOTS AROUND
900 MB. THIS MAY CREATE SOME VERY GUSTY CONDITIONS AS THIS BAND OF
SHOWERS MOVES EAST THROUGH EARLY AFTERNOON. THUS...WENT AHEAD AND
ISSUED A LAKE WIND ADVISORY THROUGH 23Z TODAY TO ACCOUNT FOR THESE
WINDS.
MEANWHILE...A SHARPER MID LEVEL TROUGH IS CONTINUING TO DIG OVER THE
CENTRAL ROCKIES WITH A NORTHERN STREAM WAVE PUSHING INTO THE NORTHERN
PLAINS. AS THESE TWO SYSTEMS PHASE AND MOVE EAST...IT WILL ACCELERATE
THE COLD FRONT ACROSS EASTERN KENTUCKY LATE TONIGHT. WITH GOOD
DYNAMICS IN PLACE...AND GOOD CONVERGENCE ALONG THE SURFACE
BOUNDARY...WE WILL SEE WIDESPREAD PRECIPITATION DEVELOP AS THIS
BOUNDARY MOVES EAST. A NARROW RIBBON OF INSTABILITY JUST AHEAD OF THE
FRONT COULD LEND ITSELF TO SOME LIGHTNING OVERNIGHT.
HOWEVER...INSTABILITY SHOULD REMAIN ELEVATED...AND POSE NO SEVERE
THREAT. THE BIGGER STORY WILL BE THE RETURN OF MUCH COLDER AIR INTO
EASTERN KENTUCKY FOR TUESDAY. IT DOES APPEAR SOME MOISTURE WILL
LINGER BEHIND THE COLD FRONT YIELDING AN A BRIEF OPPORTUNITY FOR SOME
SNOW TO MIX IN JUST BEFORE PRECIPITATION ENDS. MOST LOCATIONS WILL
ESCAPE ANY SNOW ACCUMULATION AS THE GROUND WILL SIMPLY BE TOO WARM.
THE EXCEPTION WILL BE IN THE HIGHEST TERRAIN ABOVE 2.5KFT AS COLDER
SURFACE TEMPERATURES MAY ALLOW FOR BETTER ACCUMULATION POTENTIAL.
WILL GO WITH UP TO 2 INCHES ON THE HIGHEST PEAKS IN SOUTHEAST
KENTUCKY. PRECIPITATION WILL COME TO AN END THROUGH THE DAY
TUESDAY...BUT SOME DRIZZLE OR FLURRIES COULD LINGER ACROSS THE HIGH
TERRAIN IN THE SOUTHEAST INTO THE AFTERNOON OR EVENING HOURS. HIGHS
WILL STRUGGLE TO REACH 40 ON TUESDAY...WITH HIGHS POSSIBLY OCCURRING
EARLY IN THE DAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 449 AM EDT MON APR 14 2014
A SURFACE RIDGE WILL BE MOVING OVER THE AREA WITH AN UNSEASONABLY
COLD AND DRY AIR MASS AT THE START OF THE PERIOD. MODELS HAVE BEEN
CONSISTENT IN THEIR SOLUTIONS...AGREEING ON CLEARING SKIES AND EASING
WINDS LEADING TO A HARD FREEZE FOR MOST LOCATIONS...AND A FREEZE
WATCH HAS BEEN ISSUED FOR TUESDAY NIGHT INTO WEDNESDAY MORNING. THE
HIGH WILL SLIP TO OUR EAST WEDNESDAY AND THURSDAY...AND WEAK WARM AIR
ADVECTION WILL RETURN. MOISTURE WILL BE SLOW TO INCREASE...SO EVEN
THOUGH AFTERNOONS WILL BE MILDER...CLEAR TO PARTLY CLOUDY SKIES WILL
ALLOW FOR A LARGE DIURNAL RANGE WITH CHILLY EARLY MORNINGS. FROST
WILL BE EXPECTED FOR MANY LOCATIONS ON WEDNESDAY NIGHT...AND POSSIBLY
ON THURSDAY NIGHT IN THE COLDEST VALLEYS.
FROM FRIDAY THROUGH THE WEEKEND THE MODELS BECOME MORE DISPARATE AS
TIME GOES BY. IN GENERAL TERMS...ANOTHER MID/UPPER LEVEL TROUGH WILL
PROGRESS EAST ACROSS THE CONUS. COMPARED TO THE GFS...THE ECMWF IS
STRONGER WITH THE SOUTHERN END OF THIS FEATURE NEAR THE GULF COAST.
MEANWHILE...THE GFS IS WEAKER NEAR THE GULF COAST...BUT MUCH MORE
AMPLIFIED ACROSS THE NORTH CENTRAL CONUS. THIS AFFECTS CORRESPONDING
SURFACE LOW DEVELOPMENT. BOTH SCENARIOS BRING THE GREATEST POP ON
FRIDAY NIGHT...BUT THE GFS IS MORE SUPPORTIVE OF PRECIP. THE
DIFFERING SURFACE PATTERNS ALSO AFFECT HOW MUCH COLDER FLOWS
SOUTHWARD DURING THE WEEKEND. SOME MEMBERS OF THE GFS ENSEMBLE VARY
QUITE A BIT FROM THE OPERATIONAL RUN...AND LEND SUPPORT TO THE ECMWF
PATTERN...BUT THE GFS ENSEMBLE MEAN SUPPORTS THE OPERATIONAL GFS.
WITH ALL THIS IN MIND...WILL CONTINUE TO USE A GENERALIZED MODEL
COMPROMISE...WITH A LOWER CONFIDENCE THAN NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 137 PM EDT MON APR 14 2014
MAINLY VFR CONDITIONS EXPECTED THROUGH AROUND 4Z TONIGHT. THE ISSUE
FOR AVIATORS TODAY WILL BE WINDS. SOUTHWESTERLY TO SOUTHEASTERLY
WINDS OF 8 TO 15 KTS WITH GUSTS OF 20 TO 30 KTS WILL BE POSSIBLE
THROUGH FOR THE REST OF THE DAY. BASED ON THE LATEST TRENDS IN RADAR
BOTH OVER EASTERN KENTUCKY AND POINTS WESTWARD...IT APPEARS THAT THE
REST OF THE DAY COULD BE RAIN FREE. IT LOOKS LIKE THE NEXT CHANCE OF
PRECIPITATION MAY NOT ARRIVE UNTIL BETWEEN 4 AND 6Z TONIGHT AT THE
TAF SITES. UNTIL THEN...THE AIRPORTS WILL CONTINUE TO EXPERIENCE
OVERCAST CIGS OF 3-6K ACROSS THE BOARD. JKL WILL LIKELY SEE THE
LOWEST CIGS THROUGH THIS EVENING. ONCE THE PRECIPITATION BEGINS...THE
TAF SITES SHOULD BEGIN TO SEE MVFR CIGS...WITH IFR CIGS POSSIBLE WHEN
WIDESPREAD LOW LEVEL CLOUD COVER AND RAIN AND SNOW SHOWERS BEGIN TO
MOVE ACROSS THE AREA BETWEEN 11 AND 14Z ON TUESDAY. TUESDAYS WEATHER
WILL FEATURE A MIX OF RAIN AND SNOW SHOWERS...WITH PERHAPS A LITTLE
BIT OF SLEET EARLY IN MORNING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY MORNING FOR
KYZ044-050>052-058>060-068-069-079-080-083>088-104-106>120.
LAKE WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR KYZ044-
050>052-058>060-068-069-079-080-083>088-104-106>120.
&&
$$
UPDATE...AR
SHORT TERM...KAS
LONG TERM...HAL
AVIATION...AR
AREA FORECAST DISCUSSION
NWS CARIBOU ME
622 PM EDT MON APR 14 2014
.SYNOPSIS...
A WARM FRONT WILL LIFT WELL NORTH OF THE AREA TONIGHT. A STRONG
COLD FRONT WILL APPROACH LATER TUESDAY THEN CROSS THE REGION
TUESDAY NIGHT.
&&
.NEAR TERM /THROUGH TUESDAY/...
600 PM UPDATE: MODELS ARE IN DISAGREEMENT WITH REGARD TO HOW FAR E
A BAND OF PRE-COLD FRONTAL SHWRS REACH INTO OUR FA LATER TNGT. OF
THE MODELS...THE 18Z GFS IS THE MOST AGGRESSIVE...BRINGING QPF
VALUES OF 0.10-0.25 AS FAR E AS W CNTRL TO NE PTNS OF THE FA.
OTHER MODELS SUCH AS THE 12Z ECMWF HARDLY BRINGS ANY RNFL EVEN
INTO THE NW PTN OF THE FA. A COMPROMISE BETWEEN THESE TWO
SCENARIOS AS SUGGESTED BY THE LATEST HRLY HRRR MODEL SIMULATED
FCST RADAR REF SUGGESTS BRINGING UPWARDS OF ARND A TENTH OF AN
INCH TO NW PTNS OF THE FA AND LESSER AMOUNTS ELSEWHERE...RESULTING
IN INCREASING POPS TO LIKELY CAT OVR THE NW LATER TNGT AND
KEEPING CHC OR LOWER POPS ELSEWHERE.
REGARDING FOG POTENTIAL...BASED ON INITIAL NO IMMEDIATE SIGNS OF
FOG...WE DELAYED THE ONSET TIL 10 PM OVR DOWNEAST AREAS TIL
PROGRESSIVELY AS LATE AS 2 AM OVR THE NW AND FAR NE...THINKING
THAT SATURATION OF THE LLVL AIR MASS WILL WORK NW FROM THE
COAST...BUT WE ARE NOT VERY CONFIDENT OF THIS TMG WITH IT POSSIBLE
THAT FOG COULD BREAK OUT SIMULTANEOUSLY OVR RELATIVELY LARGE PTNS
OF THE FA ANYTIME AFT 9 PM. LASTLY...WE UPDATED FCST HRLY TEMPS TO
UNCHGD FCST OVRNGT LOWS POSTED AT 6 AM FROM 5 PM OBSVD TEMPS.
ORGNL DISC: MAIN FOCUS REMAINS ON THE POTENTIAL FOR FLOODING FROM
ICE JAMS/RISING RIVER LEVELS AND THIS ADDRESSED IN MORE DETAIL IN
THE HYDRO SECTION BLO...
AS OF MID AFTN...MOST ALL OF THE FA NOW INTO THE WARM AIR XCPT
FOR FAR N AND NERN AREAS WHERE THE COLD AIR HAS BEEN SLOW TO ROOT
OUT... TEMPS GENERALLY IN THE MID 50S TO MID 60S W/ MID 40S STILL
AT KFVE. AFTN MIXING HAS ALLOWED THE FOG/STRATUS FROM THIS AM TO
BURN OFF BUT W/ PLENTY OF LOW-LEVEL MOISTURE FROM ALL THE SNOW
MELT AND A VRY COLD GROUND SFC SHOULD ALLOW FOG/STRATUS TO REDEVELOP
THIS EVE W/ THE LOSS OF HEATING AND MIXING.
UNSEASONABLY MILD AIR WILL PERSIST ACROSS THE REGION TNGT THRU
TUE AS A SLOW MOVG COLD FRONT NOW CROSSING THE ERN GRT LAKES
APPROACHES OUR AREA LATER TUE. EXPECT TEMPS TO ONLY DROP INTO THE
UPPER 40S TO 50S MOST AREAS WILL KEEP AN ACCELERATED SNOW MELT IN
PLACE. IN ADDITION TO THE MILD TEMPS AND RAPID SNOW MELT...A
SIGNIFICANT RAIN EVENT IS STILL ON TAP AS A PD OF MDT TO LOCALLY
HVY RAIN IN ADVANCE OF THIS FRONT OVERSPREADS OUR REGION FROM W-E
ON TUE AND CONTS INTO TUE NGT.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
HE COLD FRONT WILL BE APPROACHING THE MAINE/QUEBEC BORDER EARLY
TUESDAY EVENING. THE FRONT WILL BE PRECEDED AND ACCOMPANIED BY
WIDESPREAD STEADY RAINFALL TUESDAY NIGHT AS THE FRONT CROSSES THE
REGION FROM THE WEST. TEMPERATURES ARE EXPECTED TO REMAIN ABOVE
FREEZING MOST OF TUESDAY EVENING. THE COMBINATION OF THE RAINFALL
AND ABOVE FREEZING TEMPERATURES WILL RESULT IN CONTINUED SNOW
MELT/RUNOFF RESULTING IN RIVER RISES AND ICE MOVEMENT. SEE THE
HYDROLOGY SECTION BELOW FOR MORE DETAILED INFORMATION. COLDER AIR
FILTERING IN BEHIND THE COLD FRONT WILL RESULT IN THE POSSIBILITY OF
LINGERING RAIN CHANGING TO SNOW SHOWERS LATER TUESDAY NIGHT AND
EARLY WEDNESDAY MORNING ACROSS NORTHERN AREAS BEFORE THE
PRECIPITATION ENDS. LITTLE IF ANY SNOW ACCUMULATION IS
EXPECTED.
A LARGE RIDGE OF HIGH PRESSURE WILL BUILD EAST TOWARD THE REGION
DURING WEDNESDAY AFTERNOON WITH CLEARING SKIES EXPECTED. HIGHS ON
WEDNESDAY WILL BE BELOW NORMAL LEVELS WITH HIGHS ON WEDNESDAY IN THE
LOW TO MID 30S NORTH AND UPPER 30S TO LOWER 40S ACROSS CENTRAL AND
DOWNEAST AREAS.
HIGH PRESSURE WILL SETTLE ACROSS THE AREA WEDNESDAY NIGHT WITH CLEAR
SKIES AND LIGHT WINDS. LOWS WEDNESDAY NIGHT WILL RANGE FROM THE MID
TO UPPER TEENS NORTH AND LOW TO MID 20S CENTRAL AND DOWNEAST.
HIGH PRESSURE WILL MOVE EAST THURSDAY MOSTLY SUNNY SKIES EXPECTED.
HIGHS WILL BE CLOSE TO NORMAL FOR THIS TIME OF YEAR.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE PERIOD WILL BEGIN WITH MAINE UNDER THE INFLUENCE OF A SURFACE
HIGH PRESSURE. THIS HIGH PRESSURE WILL SLIDE EAST THROUGH THE AREA
THURSDAY NIGHT. A WEAK SHORTWAVE WILL BRING SOME CLOUDS ACROSS THE
NORTH THURSDAY NIGHT INTO FRIDAY. CLOUDS WILL BEGIN TO FILL IN
ACROSS THE AREA MORE AS WE GO INTO FRIDAY NIGHT AHEAD OF APPROACHING
DISTURBANCE. THERE IS SOME CONTINUED MODEL DISAGREEMENT WITH
EVOLUTION OF THIS NEXT SYSTEM. RIGHT NOW THE GFS BRINGS A
SHORTWAVE AND SURFACE LOW ACROSS THE REGION SATURDAY NIGHT INTO
EARLY SUNDAY. WHILE THE ECMWF WANTS TO BRING THE SHORTWAVE ACROSS
THE REGION BUT KEEPS THE SURFACE LOW MOSTLY SOUTH OFF THE COAST OF
MAINE. SINCE THERE IS STILL SOME DISAGREEMENT WITH THIS WILL STICK
WITH THE BLEND APPROACH WITH NO MAJOR ADJUSTMENTS DURING THIS
PERIOD. THIS DISTURBANCE SLIDES EAST AND ANOTHER AREA OF HIGH
PRESSURE PROGRESSES EAST FOR MONDAY. TEMPERATURES THROUGH THE
PERIOD WILL BE NEAR TO SLIGHTLY ABOVE NORMAL.
&&
.AVIATION /22Z MONDAY THROUGH SATURDAY/...
NEAR TERM: STRATUS/FOG HAS BURNED OFF ALL BUT KFVE AS VERY WARM
AIR HAS OVERSPREAD THE FA AND ALLOWED THE LOWER LEVEL MOISTURE TO
MIX OUT. MELTING SNOW WILL LEAVE ABUNDANT LOW-LEVEL MOISTURE IN
PLACE AND W/ A VRY COLD SFC...FOG/STRATUS LIKELY TO REDEVELOP THIS EVE
AFTER THE LOSS OF HEATING AND PERSIST INTO AT LEAST TUE AM.
THUS...EXPECT VFR CONDS THIS AFTN AND ERLY EVE TO GIVE WAY TO LIFR
AGAIN ALL TAF SITES BY LATE EVE W/ THESE CONDS CONTG TUE. A SLOW
MOVG COLD FRONT APPROACHING FROM THE W WILL LIKELY HELP KEEP
PRIMARILY IFR CONDS ACROSS THE AREA THRU TUE...
SHORT TERM: IFR CONDITIONS ARE EXPECTED TUESDAY NIGHT. SOME EARLY MORNING
IFR/MVFR IS POSSIBLE ACROSS EASTERN TERMINALS OTHERWISE VFR IS
EXPECTED BY WEDNESDAY AFTERNOON. VFR IS THEN EXPECTED THROUGH
THURSDAY.
&&
.MARINE...
NEAR TERM: HAVE DROPPED THE GLW WATCH IN FAVOR OF A GLW WRNG FROM
12Z TUE THRU 08Z WED... BRISK SRLY WNDS AHEAD OF A SLOW MOVG COLD
FRONT WILL AFFECT THE WATERS UNTIL A STRONG COLD FRONT CROSSES
THE WATERS ERLY WED AM...
SHORT TERM: A GALE WARNING WILL BE IN EFFECT THROUGH TUESDAY NIGHT.
WINDS/SEAS WILL THEN DIMINISH TO SMALL CRAFT ADVISORY CONDITIONS.
WINDS WILL THEN DIMINISH LATER WEDNESDAY AS THE HIGH BUILDS EAST
HOWEVER SEAS MAY REMAIN AT SMALL CRAFT ADVISORY LEVELS INTO EARLY
THURSDAY.
&&
.HYDROLOGY...
THE FLOOD WATCH REMAINS IN EFFECT THRU WED... UNSEASONABLY WARM
AIR CONTS TO SPREAD ACROSS THE AREA W/ TEMPS NOW INTO THE 60S ALL
BUT FAR N AND NERN AREAS AND ALONG THE IMMEDIATE COAST. W/ THE WARM
AIR HAVING JUST ARRIVED THIS AFTN...WILL BE A BIT OF A LAG BEFORE
RIVERS/STREAMS BEGIN TO RESPOND TO THE INCREASED SNOW MELT. RIVER
GAGES CONT TO SHOW SLOW RISES BUT THIS SHOULD INCREASE OVER THE
NXT 6-12 HRS AND APPEARS WE ARE ABOUT TO ENTER INTO THE MAIN
THREAT WINDOW FOR SIGNIFICANT FLOODING POTENTIAL ACROSS OUR
REGION.
TO FURTHER EXTENUATE CONCERNS...TEMPS WILL REMAIN WELL ABV
FREEZING TNGT THRU TUE ALLOWING FOR CONTD ACCELERATED SNOW MELT AND
MODERATE TO HEAVY RAIN WILL OCCUR ACROSS THE REGION LATER TUESDAY
INTO TUESDAY NIGHT IN ADVANCE OF THE SLOW MOVING COLD FRONT. THE
THREAT OF ICE JAM FLOODING WILL CONT TO INCREASE FROM NOW THRU
TUE WITH STILL RISING RIVER LEVELS. THE THREAT OF ICE JAM FLOODING
WILL THEN PERSIST TUESDAY NIGHT THROUGH WEDNESDAY WHILE RIVER
LEVELS CONTINUE TO RISE AND ICE MOVEMENT CONTINUES. FINALLY...THE
RAPIDLY MELTING SNOW MAY ALSO CAUSE SOME FLOODING OF LOW LYING
AREAS AND ROADWAYS.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...FLOOD WATCH THROUGH WEDNESDAY EVENING FOR MEZ001>006-010-011-
015>017-029>032.
MARINE...GALE WARNING FROM 8 AM TUESDAY TO 4 AM EDT WEDNESDAY FOR
ANZ050>052.
&&
$$
NEAR TERM...VJN
SHORT TERM...DUDA
LONG TERM...JORDAN
AVIATION...VJN/DUDA
MARINE...VJN/DUDA
HYDROLOGY...KHW
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
144 PM EDT MON APR 14 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 325 AM EDT MON APR 14 2014
A LOW PRESSURE SYSTEM CENTERED NEAR CHICAGO EARLY THIS MORNING
WILL CONTINUE TO BRING RAIN SHOWERS TODAY. PRECIPITATION WILL
GRADUALLY BECOME MIXED WITH AND CHANGE OVER TO SNOW SHOWERS AS
COLDER AIR MOVES IN ON THE BACK SIDE OF A LOW PRESSURE SYSTEM THAT
WILL CONTINUE TO TRACK NORTHEAST INTO ONTARIO. IT WILL BE BREEZY
TODAY AS WELL. TEMPERATURES WILL BE UNSEASONABLY COLD TUESDAY
BEFORE UNDERGOING A MODERATING TREND WEDNESDAY THROUGH THURSDAY.
&&
.UPDATE...
ISSUED AT 1209 PM EDT MON APR 14 2014
SENT AN UPDATE TO MAKE SOME MINOR ADJUSTMENTS TO THE
FORECAST...BUT OVERALL THINGS PROGRESSING AS EXPECTED.
TEMPERATURES PLUNGED BEHIND THE COLD FRONT THIS MORNING WHICH HAS
NOW PROGRESSED JUST EAST OF THE FORECAST AREA INTO SOUTHEAST
LOWER. GRAND RAPIDS DROPPED ABOUT 20 DEGREES IN AN HOUR WITH THE
FRONTAL PASSAGE. EXPECTING THE TEMPERATURES TO CONTINUE A SLOW
FALL THIS AFTERNOON ON NORTHERLY COLD AIR ADVECTION WINDS. BY
EVENING TEMPERATURES WILL RANGE FROM THE UPPER 20S TOWARD
LUDINGTON TO THE UPPER 30S AT JACKSON. SKIES WILL REMAIN MOSTLY
CLOUDY THIS AFTERNOON WITH NORTH-NORTHWEST WINDS OF 15-25 MPH.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 325 AM EDT MON APR 14 2014
SHOWERS WILL CONTINUE TO LINGER THIS MORNING AS LOW PRESSURE NEAR
ORD EARLY THIS MORNING TRACKS NE TO SAGINAW BAY BY 12Z AND FURTHER
NE INTO ONTARIO BY MIDDAY. FAIRLY WINDY CONDITIONS ARE ANTICIPATED
TODAY AS BRISK NW FLOW CAA OCCURS ON THE BACK SIDE OF THE SYSTEM.
GUSTY WINDS ARE ALREADY NOTED OVER NORTH/CENTRAL IL INTO NORTHERN
INDIANA. HIGHER RES GUIDANCE SUCH AS THE HRRR SUGGESTS SOME GUSTS
MAY BRIEFLY REACH AROUND 40 TO NEAR 45 MPH ALONG I-94 AND ESPECIALLY
IN OUR FAR SE FCST AREA TOWARD JXN LATER THIS MORNING. THIS IN
ADDITION TO A FEW GUSTS TO AROUND 40 TO 45 MPH RIGHT ALONG THE LAKE
MI SHORELINE. OVERALL THOUGH FELT A WIND ADVISORY IS NOT NEEDED
TODAY SINCE THE MAJORITY OF OUR AREA WILL NOT SEE GUSTS AS HIGH AS
45 MPH.
PCPN WILL GRADUALLY BECOME MIXED WITH THEN CHANGE OVER TO LIGHT
SNOW SHOWERS FROM NW TO SE ACROSS OUR FCST AREA TODAY AS THE CAA
OCCURS. VERY LITTLE TO NO ACCUMULATION IS EXPECTED TODAY. HOWEVER
AS TEMPERATURES CONTINUE TO FALL INTO THE 20S TONIGHT WE DO EXPECT
LIGHT ACCUMULATIONS ACROSS MOST OF OUR FCST AREA RANGING FROM A
FEW TENTHS OF AN INCH TO LOCALLY AS MUCH AS TWO INCHES. LINGERING
LIGHT SNOW SHOWERS TUESDAY MORNING WILL TAPER OFF TO FLURRIES BEFORE
ENDING AND IT WILL BE UNSEASONABLY COLD WITH MAX TEMPS ONLY IN THE
30S.
HIGH PRESSURE WILL BUILD IN TO PRODUCE FAIR BUT COLD WX TUESDAY
NIGHT. FAIR WX WILL CONTINUE WEDNESDAY ALONG WITH MUCH MILDER
TEMPS AS FLOW BECOMES SOUTHERLY ON THE BACKSIDE OF THE DEPARTING
HIGH.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 325 AM EDT MON APR 14 2014
NO BIG STORMS EXPECTED IN THE EXTENDED PERIOD. THERE WILL BE SOME
RAIN BUT CONVECTION IS NOT LIKELY SO AMOUNTS SHOULD NOT BE
EXCESSIVE. TWO LOW PRESSURE CENTERS WILL BE MOVING THROUGH FROM
WEDNESDAY NIGHT INTO SATURDAY NIGHT WITH THE HIGHEST CHANCES FOR
RAIN ON FRIDAY NIGHT. MODEL SOUNDINGS SUGGEST RAIN COULD MIX WITH
WET SNOW ACROSS THE NORTH WEDNESDAY NIGHT AND AGAIN SATURDAY NIGHT
BUT CONDITIONS WERE MARGINAL ENOUGH TO LEAVE OUT OF THE FORECAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 140 PM EDT MON APR 14 2014
A DEEP TROUGH IS APPROACHING AND WILL SPREAD LIGHT SNOW INTO THE
AREA THIS EVENING. SOLID MVFR CONDITIONS EXPECTED. THE PERIOD OF
SNOW LOOKS TO BE FROM AROUND 01Z THROUGH 09Z OR SO. A FEW LAKE
EFFECT SNOW SHOWERS MAY FALL AT THE WESTERN TAF SITES TUESDAY BUT
VFR CONDITIONS EXPECTED.
&&
.HYDROLOGY...
ISSUED AT 1209 PM EDT MON APR 14 2014
AREAL FLOOD WARNINGS REMAIN ACROSS CENTRAL LOWER MICHIGAN.
WIDESPREAD FLOODING CONTINUES IN LOW LYING AREAS AS WELL AS WHERE SMALLER
CREEKS AND STREAMS HAVE COME OUT OF THERE BANKS. ON TOP OF THAT
THE 3-5 INCHES OF RAIN THAT FELL ACROSS CENTRAL LOWER MICHIGAN HAS
RESULTED IN SIGNIFICANT MAINSTEM RIVERS FLOODING. EVART IS
FORECAST TO GO TO NEAR RECORD FLOODING AT 15.0 FT. THE BULK OF THE
FLOODING ISSUES ARE ACROSS THE PERE MARQUETTE...WHITE...
MUSKEGON... PINE AND CHIPPEWA RIVER BASINS. THE ONLY RIVER WARNING
IN THE GRAND RIVER BASIN IS THE ROGUE AT ROCKFORD. THE NORTHERN
PORTIONS OF THIS RIVER BASIN SAW HEAVIER RAINS THAT WILL ROUTE
DOWNSTREAM IN THE NEXT COUPLE DAYS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...DUKE
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...OSTUNO
AVIATION...93
HYDROLOGY...DUKE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
109 PM EDT MON APR 14 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 533 AM EDT MON APR 14 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER
THE WEST COAST AND A DOWNSTREAM TROUGH FROM HUDSON BAY THE NRN AND
CNTRL PLAINS. A POTENT WELL DEFINED SHORTWAVE TROUGH WITH COMMA
RADAR SIGNATURE WAS LIFTING NORTHEAST INTO SW WI. THE COMBINATION OF
UPPER LEVEL DIV WITH THE RIGHT ENTRANCE OF THE 140-150 KNOT 300 MB
JET OVER NRN ONTARIO...STRONG QVECTOR CONV AND 700-500 MB FGEN
SUPPORTED MODERATE TO HEAVY SNOW FROM N CNTRL WI THROUGH CNTRL UPPER
MI. RADAR INDICATED THE HIGHER REFLECTIVITY ALIGNED WITH THE MAX
FGEN FROM NEAR IMT TO SE MARQUETTE COUNTY. TWO TO THREE INCHES HAD
FALLEN IN MANY LOCATIONS OF CNTRL UPPER MI BY 09Z WITH ONE INCH TO THE
SE AT ISQ. GIVEN THE WET HEAVY NATURE OF THE SNOW...SLR VALUES WERE
LOW...GENERALLY AT OR BELOW 10/1.
TODAY...AS THE SHORTWAVE LIFTS TO THE NORTHEAST...EXPECT THE SNOW TO
GRADUALLY DIMINISH THIS MORNING AROUND 15Z. ADDITIONAL ACCUMULATIONS
OF 2 TO 3 INCHES WOULD BRING TOTALS INTO THE 3 TO 6 INCH RANGE. THE
STRONG UPSLOPE NRLY FLOW WILL ALSO HELP BOOST SNOW AMOUNTS TOWARD
THE HIGHER END OF THE RANGE OVER THE HIGHER TERRAIN OF N CNTRL UPPER
MI. ALTHOUGH WINDS GUSTING TO 35 MPH WILL ALSO PRODUCE BLOWING
SNOW...THE SNOW WAS WET ENOUGH SO THAT VSBYS WERE MAINLY ABOVE
1/2SM. SOME LOCALIZED LOWER VSBY WOULD BE EXPECTED NEAR THE LAKE
SUPERIOR SHORELINE. AS THE STRONGER DYNAMICS LIFT OUT BY THIS
AFTERNOON SOME LIGHT SNOW WILL CONTINUE INTO THE NORTH AS 850 MB
TEMPS DROPPING TO AROUND -16C AND SOME LIMITED OPEN WATER PROVIDES
ENOUGH HEAT/MOISTURE FOR ADDITIONAL LAKE EFFECT AND OROGRAPHIC SNOW
FOR HIGHER TERRAIN LOCATIONS.
TONIGHT...ANY LINGERING LAKE EFFECT SNOW WILL DIMINISH BUT COULD
STILL PRODUCE A DUSTING OVER THE NORTH. MUCH COLDER AIR WILL MOVE IN
WITH MIN READINGS INTO THE 5F TO 15F RANGE.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 417 AM EDT MON APR 14 2014
LONGWAVE TROUGH AXIS ACROSS THE GREAT LAKES ON TUESDAY. QUITE CHILLY
WITHIN THE TROUGH WITH H85 TEMPS DOWN TO -20C OVER LK SUPERIOR.
SHORTWAVE DROPPING SE IN THE MEAN TROUGH INCREASES DEPTH OF QUALITY
OF MOISTURE AND ALSO STEEPENS H9-H7 LAPSE RATES ON TUESDAY. LAKE
EFFECT FLURRIES MAY TRANSITION TO DIURNALLY DRIVEN SNOW SHOWERS WITH
COVERAGE EXTENDING INLAND TOWARD WI BORDER AND LK MICHIGAN SHORE.
POPS LOW CHANCE AT BEST THOUGH. TEMPS WILL BE VERY COOL FOR THIS
TIME OF YEAR WITH READINGS IN THE LOW-MID 20S NORTH AND AROUND 30
IN THE SOUTHERN CWA. NORMAL HIGHS ARE INTO THE LOWER 50S OVER THE
SOUTH. WAVE MOVES EAST ON TUESDAY EVENING WHICH SHOULD ALLOW SKIES
TO TEMPORARILY CLEAR OUT AHEAD OF NEXT SYSTEM THAT BEGINS TO IMPACT
FAR WEST CWA WITH LGT SNOW LATE TUESDAY NIGHT. MIN TEMPS MAY DIP
INTO SINGLE DIGITS FOR MANY AREAS BEFORE THICKER CLOUDS MOVE BACK
IN LATER DURING THE NIGHT.
WHAT TO DO WITH SYSTEM FOR WEDNESDAY WILL BECOME LARGER FOCUS ONCE
WE GET PAST SYSTEM BRINGING SNOW TO MUCH OF UPR MICHIGAN TODAY. WILL
TWO CAMPS STILL PRESENT IN THE MODELS. NAM/GFS BRING SHORTWAVE AND SFC
LOW PRESSURE AND INVERTED TROUGH ACROSS UPPER MISSISSIPPI RIVER
VALLEY QUICKER...AND HAVE MORE QPF. BOTH CAMPS OF MODELS GENERATE QPF
INTO WESTERN CWA BY 12Z WEDNESDAY...SUPPORTED BY LARGER SCALE
DIFFLUENCE ALOFT BTWN JETS EMERGING FM THE PLAINS AND CROSSING LK
SUPERIOR REGION. ECMWF AND GEM-NH AND UKMET ARE SLOWER AND NOT AS
HEAVY WITH QPF OVER UPR MICHIGAN...KEEPING FOCUS FOR HEAVIER PRECIP
OVER CNTRL MN INTO WCNTRL WI ALONG TRACK OF SFC LOW PRESSURE WAVE
THROUGH MUCH OF WEDNESDAY BEFORE LIFTING IT ACROSS MAINLY WESTERN
HALF OF UPR MICHIGAN LATER WEDNESDAY INTO WEDNESDAY NIGHT. DESPITE
MODEL DIFFERENCES...ENOUGH EVIDENCE TO PUSH POPS TO LIKELY WEDNESDAY
AND WEDNESDAY NIGHT. ALSO THERE IS DECENT AGREEMENT THAT WESTERN AND
PROBABLY CENTRAL CWA WILL SEE MODERATE SNOW AMOUNTS FROM THIS
SYSTEM...WITH BULK OF SNOW FALLING WEDNESDAY AFTN THROUGH EARLY
THURSDAY MORNING. MIXING RATIOS 2.5-3G/KG WOULD SUPPORT MODERATE SNOW
AMOUNTS OF 3 TO 6 INCHES OVER 12 HOUR PERIOD. MODELS SHOWING AREA OF
MID-LEVEL FGEN...FAIRLY STRONG CONSIDERING HOW FAR OUT WE ARE
STILL...THAT COULD RESULT IN BANDS OF HEAVIER SNOW OVER LIKELY THE
WEST CWA. HPC HEAVY SNOW GRAPHICS SHOW MUCH OF FAVORED AREA WITH
MODERATE PROBABILITY OF SEEING 4 INCHES OF SNOW WITH LOW PROBABILITY
OF SEEING 8 INCHES. BASED ON 1000-850MB AND 850-700MB THICKNESSES AND
H85 TEMPS...SNOW WILL MIX WITH AND COULD CHANGE TO RAIN LATER
WEDNESDAY NIGHT OVER SCNTRL AND EAST CWA. RAIN/SNOW MIX CONTINUES
INTO THURSDAY FOR THOSE AREAS WHILE WIDESPREAD SNOW DIMINISHES
ELSEWHERE. NO WATCH ATTM...AS IT WOULD BE LATER 5TH PERIOD AND STILL
NEED TO GET THROUGH THIS ONGOING SNOW SYSTEM TO AVOID ANY CONFUSION.
WILL CONTINUE TO MENTION IN EHWO/HWOMQT.
LATER THURSDAY AND ON INTO NEXT WEEKEND THE FORECAST IS AT BEST
MUDDLED...WHICH LEADS TO LOWER THAN AVERAGE CONFIDENCE FOR SURE. GFS
MORE OR LESS IS FAIRLY CONSISTENT IN SHOWING SHORTWAVE IN SOUTHERN
STREAM LIFTING ACROSS UPPER GREAT LAKES WHILE PHASING WITH NORTHERN
BRANCH SHORTWAVE TROUGH. RESULT IS WRAPPED UP SFC LOW WITH
WIDESPREAD RAIN AND SNOW OVER UPR MICHIGAN. GEM-NH SUPPORTS IDEA
SOMEWHAT THOUGH IT IS SLOWER AND NOT AS STRONG. ECMWF WAS TRENDING
NORTH AND WEST WITH THAT SYSTEM...BUT WITH LATEST RUN NOW HAS WENT
BACK TO THE SOUTHEAST...KEEPING MUCH OF UPR MICHIGAN DRY ON FRIDAY.
ECMWF IS NOT PHASING THE SOUTHERN WAVE NEAR AS MUCH AS GFS ATTEMPTS
TO SHOW. CONSENSUS POPS...CAPPED AT LOW CHANCE...WILL BE UTILIZED
FOR NOW. WHATEVER LOW PRESSURE SYSTEM WOULD BE EXITING TO START THE
WEEKEND...WITH HIGH PRESSURE AND DRIER WEATHER FOR THE REST OF THE
WEEKEND AS SHOWN BY GFS. NOT SO INDICATES THE ECMWF...WITH A QUICK
PUSH OF NEXT SHORTWAVE ENERGY AND SFC TROUGH/RAIN SHOWERS FOR
SUNDAY. LATEST RUN BACKED OFF SOME...BUT JUST SHOWS THE HIGH
VARIABILITY THAT CURRENTLY EXISTS FOR THAT FORECAST TIME FRAME. ONE
PRETTY SURE THING IS IT LOOKS LIKE WARMING TREND /TEMPS TRYING TO
RETURN TOWARD AVERAGE/ DEVELOPS NEXT WEEKEND AFTER WHAT APPEARS TO
BE A CHILLY MID APRIL WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 108 PM EDT MON APR 14 2014
AT SAW...LIFR CONDITIONS WILL GRADUALLY IMRPROVE TO MVFR BY MID
AFTERNOON AS THE ARRIVAL OF DRIER AIR...DAYTIME HEATING AND
SLOWLY WEAKENING PRES GRADIENT/WINDS ARRIVE. MVFR CONDITIONS WILL
PREDOMINATE THROUGH THE REST OF THE FCST PERIOD.
IWD/CMX...MVFR CONDITIONS WILL CONTINUE THROUGH THE PERIOD WITH LAKE
EFFECT CLOUDS AROUND CAUSING MVFR CIGS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 417 AM EDT MON APR 14 2014
NORTH GALES 35-40 KNOTS FOR TODAY...MAINLY EAST HALF...AS LOW
PRESSURE SYSTEM TRACKS ACROSS LOWER MICHIGAN THIS MORNING AND
EVENTUALLY ACROSS QUEBEC BY THIS EVENING. WINDS QUICKLY DIMINISH
BY THIS EVENING AND SHOULD REMAIN BLO 20 KTS OVER MOST OF THE LAKE
THROUGH TUESDAY. LOW PRESSURE SYSTEM LIFTING ACROSS UPPER GREAT
LAKES LATER ON WEDNESDAY WILL RESULT IN EAST TO NORTHEAST WINDS UP
TO 25 KTS OVER MAINLY WESTERN LAKE INTO THURSDAY. WINDS DIMINISH TO
LESS THAN 20 KTS REST OF THE FORECAST PERIOD.
&&
.HYDROLOGY...
ISSUED AT 417 AM EDT MON APR 14 2014
REPORTS OF ICE JAMS IN DELTA COUNTY SUNDAY ON ESCANABA RIVER AND
ASSOCIATED TRIBUTARIES. HYDROLOGIC STATEMENT WAS ISSUED SUNDAY
EVENING AND THIS IS VALID THROUGH THIS EVENING. PRECIPITATION OCCURS
MAINLY IN THE FORM OF SNOW TODAY. OPPORTUNITIES FOR WIDESPREAD
PRECIPITATION ALSO IN THE FORECAST FOR WEDNESDAY THROUGH THURSDAY...
AND POSSIBLY FRIDAY. FEASIBLE THAT TOTAL PRECIPITATION FOR THIS WEEK
MAY EXCEED AN INCH IN SOME AREAS OF UPPER MICHIGAN. THIS PRECIP
ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES
OVER MAINLY WESTERN UPPER MICHIGAN WILL RESULT IN ANOTHER PERIOD
OF SNOWMELT AND RUNOFF ONCE WARMER TEMPERATURES MOVE BACK INTO THE
REGION BY NEXT WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ007-
013-014-085.
LAKE SUPERIOR...
GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR LSZ249>251-266-
267.
GALE WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR LSZ244-245-264-
265.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...07
MARINE...JLA
HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1210 PM EDT MON APR 14 2014
LATEST UPDATE...
UPDATE/HYDRO
.SYNOPSIS...
ISSUED AT 325 AM EDT MON APR 14 2014
A LOW PRESSURE SYSTEM CENTERED NEAR CHICAGO EARLY THIS MORNING
WILL CONTINUE TO BRING RAIN SHOWERS TODAY. PRECIPITATION WILL
GRADUALLY BECOME MIXED WITH AND CHANGE OVER TO SNOW SHOWERS AS
COLDER AIR MOVES IN ON THE BACK SIDE OF A LOW PRESSURE SYSTEM THAT
WILL CONTINUE TO TRACK NORTHEAST INTO ONTARIO. IT WILL BE BREEZY
TODAY AS WELL. TEMPERATURES WILL BE UNSEASONABLY COLD TUESDAY
BEFORE UNDERGOING A MODERATING TREND WEDNESDAY THROUGH THURSDAY.
&&
.UPDATE...
ISSUED AT 1209 PM EDT MON APR 14 2014
SENT AN UPDATE TO MAKE SOME MINOR ADJUSTMENTS TO THE
FORECAST...BUT OVERALL THINGS PROGRESSING AS EXPECTED.
TEMPERATURES PLUNGED BEHIND THE COLD FRONT THIS MORNING WHICH HAS
NOW PROGRESSED JUST EAST OF THE FORECAST AREA INTO SOUTHEAST
LOWER. GRAND RAPIDS DROPPED ABOUT 20 DEGREES IN AN HOUR WITH THE
FRONTAL PASSAGE. EXPECTING THE TEMPERATURES TO CONTINUE A SLOW
FALL THIS AFTERNOON ON NORTHERLY COLD AIR ADVECTION WINDS. BY
EVENING TEMPERATURES WILL RANGE FROM THE UPPER 20S TOWARD
LUDINGTON TO THE UPPER 30S AT JACKSON. SKIES WILL REMAIN MOSTLY
CLOUDY THIS AFTERNOON WITH NORTH-NORTHWEST WINDS OF 15-25 MPH.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 325 AM EDT MON APR 14 2014
SHOWERS WILL CONTINUE TO LINGER THIS MORNING AS LOW PRESSURE NEAR
ORD EARLY THIS MORNING TRACKS NE TO SAGINAW BAY BY 12Z AND FURTHER
NE INTO ONTARIO BY MIDDAY. FAIRLY WINDY CONDITIONS ARE ANTICIPATED
TODAY AS BRISK NW FLOW CAA OCCURS ON THE BACK SIDE OF THE SYSTEM.
GUSTY WINDS ARE ALREADY NOTED OVER NORTH/CENTRAL IL INTO NORTHERN
INDIANA. HIGHER RES GUIDANCE SUCH AS THE HRRR SUGGESTS SOME GUSTS
MAY BRIEFLY REACH AROUND 40 TO NEAR 45 MPH ALONG I-94 AND ESPECIALLY
IN OUR FAR SE FCST AREA TOWARD JXN LATER THIS MORNING. THIS IN
ADDITION TO A FEW GUSTS TO AROUND 40 TO 45 MPH RIGHT ALONG THE LAKE
MI SHORELINE. OVERALL THOUGH FELT A WIND ADVISORY IS NOT NEEDED
TODAY SINCE THE MAJORITY OF OUR AREA WILL NOT SEE GUSTS AS HIGH AS
45 MPH.
PCPN WILL GRADUALLY BECOME MIXED WITH THEN CHANGE OVER TO LIGHT
SNOW SHOWERS FROM NW TO SE ACROSS OUR FCST AREA TODAY AS THE CAA
OCCURS. VERY LITTLE TO NO ACCUMULATION IS EXPECTED TODAY. HOWEVER
AS TEMPERATURES CONTINUE TO FALL INTO THE 20S TONIGHT WE DO EXPECT
LIGHT ACCUMULATIONS ACROSS MOST OF OUR FCST AREA RANGING FROM A
FEW TENTHS OF AN INCH TO LOCALLY AS MUCH AS TWO INCHES. LINGERING
LIGHT SNOW SHOWERS TUESDAY MORNING WILL TAPER OFF TO FLURRIES BEFORE
ENDING AND IT WILL BE UNSEASONABLY COLD WITH MAX TEMPS ONLY IN THE
30S.
HIGH PRESSURE WILL BUILD IN TO PRODUCE FAIR BUT COLD WX TUESDAY
NIGHT. FAIR WX WILL CONTINUE WEDNESDAY ALONG WITH MUCH MILDER
TEMPS AS FLOW BECOMES SOUTHERLY ON THE BACKSIDE OF THE DEPARTING
HIGH.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 325 AM EDT MON APR 14 2014
NO BIG STORMS EXPECTED IN THE EXTENDED PERIOD. THERE WILL BE SOME
RAIN BUT CONVECTION IS NOT LIKELY SO AMOUNTS SHOULD NOT BE
EXCESSIVE. TWO LOW PRESSURE CENTERS WILL BE MOVING THROUGH FROM
WEDNESDAY NIGHT INTO SATURDAY NIGHT WITH THE HIGHEST CHANCES FOR
RAIN ON FRIDAY NIGHT. MODEL SOUNDINGS SUGGEST RAIN COULD MIX WITH
WET SNOW ACROSS THE NORTH WEDNESDAY NIGHT AND AGAIN SATURDAY NIGHT
BUT CONDITIONS WERE MARGINAL ENOUGH TO LEAVE OUT OF THE FORECAST.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 744 PM EDT SUN APR 13 2014
IMPACTS WILL INCREASE THROUGH THE NIGHT FOR AVIATORS. IFR LOOKS
LIKELY ESPECIALLY KGRR AND KMKG WITH THE HEAVIER RAIN.
THUNDERSTORMS WILL BE AROUND AS WELL ESPECIALLY WEST OF KLAN AND
KJXN.
WINDS WILL INCREASE AND VALUES OVER 30 KTS EXPECTED. A SHARP WIND
SHIFT IS EXPECTED MONDAY MORNING INTO THE AFTERNOON. TEMPERATURES
WILL TURN COLDER AFTER THE WIND SHIFT. ICING MAY BECOME AN ISSUE
MONDAY AFTERNOON.
&&
.HYDROLOGY...
ISSUED AT 1209 PM EDT MON APR 14 2014
AREAL FLOOD WARNINGS REMAIN ACROSS CENTRAL LOWER MICHIGAN.
WIDESPREAD FLOODING CONTINUES IN LOW LYING AREAS AS WELL AS WHERE SMALLER
CREEKS AND STREAMS HAVE COME OUT OF THERE BANKS. ON TOP OF THAT
THE 3-5 INCHES OF RAIN THAT FELL ACROSS CENTRAL LOWER MICHIGAN HAS
RESULTED IN SIGNIFICANT MAINSTEM RIVERS FLOODING. EVART IS
FORECAST TO GO TO NEAR RECORD FLOODING AT 15.0 FT. THE BULK OF THE
FLOODING ISSUES ARE ACROSS THE PERE MARQUETTE...WHITE...
MUSKEGON... PINE AND CHIPPEWA RIVER BASINS. THE ONLY RIVER WARNING
IN THE GRAND RIVER BASIN IS THE ROGUE AT ROCKFORD. THE NORTHERN
PORTIONS OF THIS RIVER BASIN SAW HEAVIER RAINS THAT WILL ROUTE
DOWNSTREAM IN THE NEXT COUPLE DAYS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...DUKE
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...OSTUNO
AVIATION...MJS
HYDROLOGY...DUKE
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
328 PM CDT Mon Apr 14 2014
.SHORT TERM: (Through Late Tonight)
Issued at 324 PM CDT Mon Apr 14 2014
Main concerns deal with the band of snow currently extending from
near Pittsfield to Rolla as well as the going freeze warning. The
band has been reducing visibilities to as low as 1/2 mile with
some reports of accumulation on grassy surfaces. It is being
caused by mid level frontogenesis ahead of the 500mb trough that
will move through the area tonight. The RAP and HRRR does show the
frotogenesis weakening as it moves acrosss the CWA, but do think
that it will likely maintain itself the next few hours before it
weakens by early evening. Have extrapolated the band through CWA
through early evening, with little or no accumulation of snow
expected given the warm low level and surface temperatures.
The precipitation and clouds will clear out quick as subsidence
moves in behind the passage of the upper trough. With cold air
advection and dry dewpoints, expect temperatures to drop quickly to
near MOS temperatures. Going freeze warning looks good and plan no
changes to it.
Britt
.LONG TERM: (Tuesday through Next Monday)
Issued at 324 PM CDT Mon Apr 14 2014
(Tuesday through Thursday)
Have kept Tuesday into Thursday dry as the area will remain cut off
from any notable moisture from the Gulf and the active storm track
stays north of the area. While Tuesday night will not be as cold as
tonight, most areas will still be in the lower to mid 30s for
lows.
(Thursday Night-Next Monday)
The ECMWF and GFS are now similar with the amplitude and timing of
the mid level trough and attendant cold front that will move across
the area on Friday. Will continue with the chance of showers on
Thursday night and Friday before subsidence works in behind the
trough keeping Friday night and Saturday dry. Then confidence
begins to wane late in the weekend as they both develop QPF over the
area. The GFS is placing more emphasis on an northern stream upper
over the Upper Midwest while ECMWF is placing it`s emphasis on a
shortwave coming out of the southwest CONUS. Either way, will
continue the chance of showers we have going Saturday night into
Sunday night. Temperatures during the period look to be near or
slightly below normal.
Britt
&&
.AVIATION: (For the 18z TAFs through 18z Tuesday Afternoon)
Issued at 1208 PM CDT Mon Apr 14 2014
Area of SN continues to move ewd. Have made some slight changes to
the prev TAFs based on latest RADAR trends and mdl guidance.
Confidence is higher that precip will be all SN at COU/UIN early
this afternoon. With ample cloud cover across the region, believe
temps will remain cold enuf for all SN at SUS/CPS late this
afternoon. However, with some uncertainty and since main focus
shud be nw of sites, will leave precip as a RA/SN mix for now.
Beyond precip, cigs shud lift quickly and remain VFR thru the
remainder of the TAF period.
Specifics for KSTL: With clouds expected to remain in place,
precip this afternoon has a better chance of being SN. However,
with placement of precip wrt the terminal, precip may remain as a
very light RA or more likely DZ. Beyond precip this afternoon,
cigs shud lift quickly to VFR and remain VFR thru the remainder of
the TAF period.
Tilly
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...FREEZE WARNING from 11 PM this evening to 9 AM CDT Tuesday FOR
Audrain MO-Boone MO-Callaway MO-Cole MO-Crawford MO-
Franklin MO-Gasconade MO-Iron MO-Jefferson MO-Knox MO-Lewis
MO-Lincoln MO-Madison MO-Marion MO-Moniteau MO-Monroe MO-
Montgomery MO-Osage MO-Pike MO-Ralls MO-Reynolds MO-Shelby
MO-St. Charles MO-St. Francois MO-St. Louis City MO-St.
Louis MO-Ste. Genevieve MO-Warren MO-Washington MO.
IL...FREEZE WARNING from 11 PM this evening to 9 AM CDT Tuesday FOR
Adams IL-Bond IL-Brown IL-Calhoun IL-Clinton IL-Fayette IL-
Greene IL-Jersey IL-Macoupin IL-Madison IL-Marion IL-Monroe
IL-Montgomery IL-Pike IL-Randolph IL-St. Clair IL-
Washington IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
122 PM CDT MON APR 14 2014
.UPDATE...
ISSUED AT 630 AM CDT MON APR 14 2014
THERE IS A WEAK DISTURBANCE IN THE NORTHWEST FLOW CURRENTLY MOVING
DOWN ACROSS THE DAKOTAS. THIS FEATURE SHOULD BRING AT LEAST A
CHANCE FOR SOME LIGHT PCPN...PROBABLY SPRINKLES OR FLURRIES...THIS
AFTERNOON TO PARTS OF EASTERN NEBRASKA. RECENT RUNS OF THE RAP AND
HRRR MODELS SHOW THAT TREND...AND THESE MAY EVEN LINGER INTO EARLY
EVENING. LOOK FOR HIGHS MAINLY FROM AROUND 40 UP TO THE LOWER AND
POSSIBLY MID 40S.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 306 AM CDT MON APR 14 2014
STLT IMAGERY THIS MORNING WAS SHOWING A ANOMALOUS LONGWAVE TROF
SITUATED OVER THE CNTRL U.S. WITH POTENT VORT MAX JUST EAST OF THE 4
CORNERS REGION. UPSTREAM THEN...HIGHLY AMPLIFIED RIDGE WAS SITUATED
OVER THE WRN CONUS/WRN CANADA. AT THE SFC...DEEP LOW PRESSURE WAS
CENTERED OVER NRN IL WITH LEADING EDGE OF ATTENDANT COLD FRONT
PUSHING DEEP INTO THE SRN PLAINS STATES. OTHERWISE AREA OF -SN HAS
FINALLY PUSHED OUT OF ERN NEB AND INTO SWRN IA. EXPECT ACTIVITY TO
TAPER OFF THOUGH BY MID MORNING.
MODELS ARE IN GOOD AGREEMENT MEAN TROF WILL PREVAIL OVER THE CONUS
THRU THE NEAR TERM PDS WITH NEXT SHOT FOR PCPN COMING WED/WED NIGHT
WHEN NEXT PAC NW SHORTWAVE MOVES ACROSS THE NRN/CNTRL PLAINS. UNTIL
THEN...TEMPS ARE THE MAIN ISSUE TO CONTEND WITH. DEEP TROF ALOFT AND
ASSOCIATED COLD AIR ADVECTION HAS RESULTED IN AN IMPRESSIVE TEMP
SWING OVER THE REGIONS OVER THE LAST 24HRS...AND AT THIS POINT COLD
AIRMASS EXPECTED TO HANG IN TIGHT AT LEAST THRU TONIGHT. COLD THEN
TODAY WITH TEMPS STRUGGLING TO REACH THE LOWER 40S. FURTHERMORE...
GUSTY NW WINDS/COLD WIND CHILL INDICES WILL ENSURE LOUSY CONDITIONS
THRU THE DAY. AS FOR HIGHS TUE/WED...MODERATE REBOUND ADVERTISED
BUT STILL JUST BELOW NORM.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 306 AM CDT MON APR 14 2014
WED AFTN/NIGHT NEXT ROUND OF PCPN WILL BE POSSIBLE IN ASSOCIATION
WITH NEXT COLD FRONT SWEEPING INTO THE CNTRL PLAINS. MODELS IN GOOD
AGREEMENT ADVERTISING DEEP LYR QG FORCING WILL BE IN PLACE AT TIME
OF FROPA. PCPN TYPE INITIALLY RA...THEN POSSIBLE RA/SN MIX WED
NIGHT/THUR MORNING WHEN BRUNT OF CAA ARRIVES. FOCUS FOR PCPN WILL
GRADUALLY SHIFT EAST THRU FRIDAY AS BEST DYNAMIC FORCING EXITS THE
REGION. SAT NIGHT/SUN...ECM IS MORE AGGRESSIVE WITH QPF OVER SRN
NEB/ERN KS IN RELATION TO 295K UPGLIDE/LOW COND PRES DEF. GOING
FCST ALREADY HAS THIS COVERED WITH SMALL POPS IN PLACE. OTHERWISE...
WARMING TREND ON TAP THRU THE EXTENDED PD WITH LOW 70S ARRIVING
EARLY NEXT WEEK.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 115 PM CDT MON APR 14 2014
A WEAK DISTURBANCE DROPPING SE INTO NCNTRL NEBR AT 18Z WILL SPREAD
CUMULUS CLOUDS ACROSS TAF SITES THROUGH LATE AFTN/EARLY EVENING
WITH OCCASIONAL CIGS GENERALLY ABOVE FL040. A FEW SNOW SHOWERS
COULD ACCOMPANY THE CIGS...ESPECIALLY AT KOFK. A PERIOD OF
LIGHTER WINDS COULD PRECEDE DISTURBANCE FOLLOWED BY INCREASING
WINDS AGAIN LATER THIS AFTN THROUGH SUNSET BEFORE WINDS DECREASE
AGAIN.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...MILLER
SHORT TERM...DEE
LONG TERM...DEE
AVIATION...CHERMOK
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1239 PM CDT MON APR 14 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT MON APR 14 2014
A WEAK UPPER LEVEL DISTURBANCE...CURRENTLY ACROSS ERN MT/WRN ND...
WILL DROP SOUTH THROUGH THE FCST AREA TODAY. LAPSE RATES FROM
850-700MB ARE STEEP AND MOIST BUT THE 850MB-SFC LAYER IS VERY DRY
WITH DEW POINTS IN THE TEENS AND LOWER 20S. WHILE TEMPERATURE RISE
IN THE LOW TO MID 40S THIS AFTN...WET BULB ZERO HEIGHTS WITH BE
CLOSE TO THE GROUND AND THE HRRR AND RAP SHOW SNOW FOR THE PTYPE. SO
ISOLATED SNOW SHOWERS ARE IN THE FORECAST.
NO MEASURABLE QPF WAS INDICATED IN THE RAP SOLN BUT THE HRRR
ACTUALLY SHOWS SCATTERED SNOW SHOWERS WITH SEVERAL STREAKS OF 0.01
QPF AND THE MODEL CONSENSUS INDICATES H700MB AROUND -18C AT KVTN
WHICH IS VERY IMPRESSIVE FOR MID APRIL.
THIS DISTURBANCE WILL DRAW ANOTHER WEAK PIECE OF ARCTIC HIGH
PRESSURE INTO THE ERN HALF OF THE FORECAST AREA TONIGHT WHILE THE
WRN HALF DEVELOPS SOUTH WINDS AS LOW PRESSURE FORMS ACROSS THE NRN
HIGH PLAINS. LOWS TONIGHT SHOULD FALL INTO THE LOW TO MID 20S WITH
GENERALLY CLEAR SKIES.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 345 AM CDT MON APR 14 2014
WARM AIR QUICKLY SPREADS NORTHEAST INTO THE REGION TUESDAY...WITH
H85 TEMPS RISING TO 8C TO 12C BY AFTERNOON. THIS SHOULD YIELD HIGHS
IN THE UPPER 50S TO MID 60S. HAVE RAISED LOWS TUESDAY NIGHT...AS
SOUTHERLY LOW LEVEL JET KEEPS ATMOSPHERE MIXED AND H85 TEMPS
CONTINUE TO WARM...NEARING 13C.
SHORTWAVE ENERGY DIVES SOUTHEAST INTO THE PLAINS LATE WEDNESDAY
THROUGH THURSDAY. MODELS CONTINUE TO MOVE THIS THROUGH QUICKLY AS AN
OPEN WAVE...WITH THE BEST UPPER LEVEL DYNAMICS CROSSING THROUGH
NORTHERN KANSAS. WILL CONTINUE THE HIGHEST POPS /NEAR 40 PERCENT/
ACROSS FAR SOUTHERN NEBRASKA. SOUNDING PROFILES INDICATE A MIX OF
RAIN AND SNOW OR WET SNOW...BUT NOT EXPECTING MUCH QPF AT THIS
POINT. CHILLY WEATHER IN THE WAKE OF THE SYSTEM THURSDAY...AS MORE
ARCTIC AIR MOVES SOUTH INTO THE PLAINS.
AS WE HEAD INTO NEXT WEEKEND...THE GFS AND ECMWF ARE BOTH
ADVERTISING UPPER LEVEL ENERGY ADVANCING EASTWARD FROM THE PACIFIC
INTO THE SOUTHWEST CONUS. THIS AIDS IN THE DEVELOPMENT OF A SURFACE
TROUGH ALONG THE HIGH PLAINS...WITH SOUTHERLY FLOW EAST OF THE
TROUGH DRAWING GULF MOISTURE NORTHWARD INTO THE PLAINS. IT WOULD
APPEAR THAT SOME TSTM ACTIVITY IS POSSIBLE SATURDAY NIGHT ON THE
NOSE OF A SOUTHERLY LOW LEVEL JET...AND THEN PERHAPS SUNDAY AS A
COLD FRONT AND LOW PRESSURE SYSTEM ADVANCE EAST ACROSS THE AREA.
ALTHOUGH BOTH MODELS DRAW MOISTURE NORTH INTO THE PLAINS...THERE ARE
DIFFERENCES IN THE HANDLING OF THE UPPER LEVEL ENERGY ACROSS THE
SOUTHWEST CONUS. WILL LEAVE THE FORECAST DRY AT THIS TIME...AS THE
MODELS SEEM TO BE JUST STARTING TO LATCH ONTO THIS SCENARIO. IF THIS
CONTINUES TO BE SHOWN IN FUTURE MODEL RUNS...THEN SOME THUNDER
MENTION WILL HAVE TO BE ADDED TO THE WEEKEND FORECAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1239 PM CDT MON APR 14 2014
ISOLATED SNOW SHOWERS WILL MOVE NORTHWEST TO SOUTHEAST ACROSS
NEBRASKA THIS AFTERNOON. FROM LATEST OBSERVATIONS...LITTLE SNOW
IS REACHING THE GROUND FROM THESE SHOWERS...SO VISIBILITY REMAINS
VFR. WOULD EXPECT THIS TREND TO CONTINUE THROUGH THE AFTERNOON
WITH THESE SHOWERS ALTHOUGH IT IS NOT ENTIRELY OUT OF THE QUESTION
TO GET CONDITIONS DETERIORATE FOR A VERY BRIEF TIME WITH LOWERED
VISIBILITIES. DID NOT INCLUDE ANY LOWERED CONDITIONS IN THE
FORECASTS AS THERE IS LITTLE CONFIDENCE IN ANY IMPACT OCCURRING AT
THE TERMINALS. OTHERWISE...WINDS WILL DIMINISH TONIGHT AND PICK
UP AGAIN FROM THE SOUTH BY LATE MORNING ON TUESDAY.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...BROOKS
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
702 PM EDT MON APR 14 2014
.SYNOPSIS...
VERY MILD WEATHER WILL CONTINUE TONIGHT WITH SCATTERED SHOWERS AND
TEMPERATURES ONLY FALLING INTO THE MID TO UPPER 50S. A STRONG COLD
FRONT WILL BRING A PERIOD OF HEAVY RAIN TO THE AREA ON TUESDAY...
FOLLOWED BY MUCH COLDER AIR AND A BRIEF CHANGE TO SNOW AND SLEET
BEFORE THE PRECIPITATION ENDS EARLY TUESDAY EVENING. WEDNESDAY
WILL BE UNSEASONABLY COLD... THE MILDER WEATHER WILL RETURN BY
LATE THIS WEEK.
&&
.NEAR TERM /UNTIL 2 AM TUESDAY MORNING/...
WARM TEMPERATURES OVER THE LAKE PLAIN WERE ENOUGH INSTABILITY TO
GET A LINE OF SHOWERS GOING WITH BRIEF HEAVY RAINS AND GUSTY WINDS
TO 40 MPH. NO CLOUD TO GROUND LIGHTNING STRIKES WERE PICKED UP BUT
SOME IN-CLOUD LIGHTNING WAS REPORTED NORTH OF PENN YAN. TEMPS
DROP ABOUT 10 DEGREES AS THE SHOWERS MOVE THROUGH BUT THEN THIS
SHOULD LEVEL OUT. THE LINE OF SHOWERS IS CONTINUING TO PROGRESS
EAST THROUGH THE CENTRAL PORTION OF OUR FORECAST AREA. BEHIND THIS
LINE TO THE WEST A CHANCE OF LIGHT SHOWERS IS POSSIBLE INTO THE
OVERNIGHT. TO THE EAST THE LINE IS EXPECTED TO STALL AND WEAKEN AS
THE SUNSETS. SCATTERED SHOWERS WILL REMAIN POSSIBLE PAST MIDNIGHT.
&&
.SHORT TERM /2 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
A STRONG COLD FRONT WILL TRACK ACROSS THE AREA THROUGH THIS PERIOD
BRINGING A PERIOD OF HEAVY RAIN TO MUCH OF THE AREA ALONG WITH
RAPIDLY FALLING TEMPERATURES AND A LIKELY CHANGE-OVER TO SNOW AND
SLEET. DETAILS ARE GIVEN BELOW.
A BAND OF SCATTERED SHOWERS MOVING ACROSS THE AREA THIS EVENING
IS STILL WELL AHEAD OF THE COLD FRONT WHICH IS BACK TO THE WEST
AROUND DTW. THESE SHOWERS WILL TEND TO LIFT NORTHEAST AND WEAKEN
THROUGH THIS EVENING BUT THERE STILL APPEARS TO BE A GOOD CHANCE
FOR A ROUND OF SHOWERS THIS EVENING AS THIS SYSTEM MOVES ACROSS
THE AREA. LATEST RAP MODEL SOUNDINGS HARDLY INDICATING ANY CAPE
OVER THE AREA THIS EVENING AND HAVE LEFT OUT ANY THUNDER MENTION.
EXPECT A LULL IN THE ACTIVITY OVER NIGHT IN THE WAKE OF THIS
SYSTEM... BEFORE RAIN BEGINS TO INCREASE WITH THE APPROACH OF THE
COLD FRONT TOWARD DAYBREAK. IT WILL BE A VERY MILD NIGHT WITH
SOUTHERLY BREEZES AND LOW TEMPERATURES MOSTLY 55 TO 60... MORE
SEASONABLE FOR JUNE THAN MID-APRIL.
A STRONG COLD FRONT WILL TRACK SLOWLY EAST ACROSS THE CWA ON
TUESDAY. THIS FRONT WILL BE ACCOMPANIED BY STRONG RIGHT-REAR QUAD
UPPER DYNAMICS AND A 50 KT LOW-LEVEL SOUTHERLY JET. INSTABILITY
ALONG AND AHEAD OF THE FRONT WILL BE MINIMAL BUT CAN`T RULE OUT A
FEW RUMBLES OF THUNDER RIGHT WITH THE FRONTAL PASSAGE DURING
MIDDAY TUESDAY. AT THIS TIME WE ARE EXPECTING SHOWERS TO INCREASE AHEAD
OF THE FRONT EARLY TUESDAY... THEN A BAND OF MODERATE TO HEAVY
RAIN WILL LIKELY ACCOMPANY AND FOLLOW THE FRONTAL PASSAGE... LATE
TUESDAY MORNING OVER THE FINGER LAKES... AROUND NOON ALONG THE
I-81 CORRIDOR... AND EARLY AFTERNOON OVER THE WESTERN CATSKILLS.
SOME CONCERN THAT ANY BAND OF HEAVY RAIN THAT DEVELOPS ALONG THE
FRONT COULD BE HEAVY ENOUGH TO CAUSE SOME MINOR FLOODING ISSUES IF
HEAVY RAIN FALLS DURING A SHORT PERIOD. TOTAL RAINFALL WITH THE
SYSTEM IS EXPECTED TO BE IN THE 1 TO 1.5 INCH RANGE. HAVE HELD OFF
ON ANY WATCHES AT THIS POINT... BUT A WATCH MAY NEED CONSIDERATION
ONCE TIMING AN LOCATION OF ANY HEAVY RAIN BANDS BECOMES MORE
CERTAIN.
SOUTHWEST WINDS WILL INCREASE TONIGHT AS THE FRONT APPROACHES.
SOME GUSTS TO 30 OR 40 MPH WILL BE POSSIBLE OVER HIGHER TERRAIN
LATER TONIGHT WITH LIGHTER WINDS AT LOWER ELEVATIONS. NORTHWEST
WINDS WILL BE STRONG AND GUSTY BEHIND THE FRONT LATE TUESDAY INTO
TUESDAY NIGHT. SOME GUSTS OF 30 TO 40 MPH ARE POSSIBLE.
THIS WILL BE AN ANAFRONT WITH SEVERAL HOURS OF PRECIPITATION
LINGERING BEHIND THE FRONT. COLD AIR MOVES IN QUICKLY BEHIND THE
FRONT WITH RAIN CHANGING TO SLEET OR A MIX OF SLEET AND SNOW OVER
THE FINGER LAKES BY LATE MORNING... AND ALONG THE I-81 CORRIDOR BY
MID TO LATE AFTERNOON. MODELS ARE IN EXCELLENT AGREEMENT WITH THIS
SCENARIO AND INDICATE THE POTENTIAL FOR A WIDESPREAD 1 TO 3 INCHES
OF SNOW AND SLEET BY EARLY EVENING TUESDAY FOR MOST OF THE AREA.
STEADIER SNOW WILL END ACROSS THE AREA EARLY TUESDAY EVENING BUT
850 MB TEMPERATURES FALL TO AROUND -15 DEGREES C. DESPITE VERY DRY
AIR EXPECT THAT THIS SCEANRIO WILL SUPPORT A LITTLE BIT OF LAKE
EFFECT SNOW OVER CENTRAL NY TUESDAY EVENING. ANY ADDITIONAL
ACCUMULATIONS SHOULD BE LIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
QUIET WX IN THE MED RNG WITH HIGH PRES BUILDING INTO THE RGN ON
WED. AFTER SOME MRNG LAKE CLDS...MOSTLY SUNNY SKIES WILL PREVAIL.
FAIR AND DRY WEATHER PERSISTS INTO FRIDAY AS THE SFC HIGH SLIDES
OFF THE CST. WE COULD SEE CLDS RETURN IN THE SELY FLOW LATER FRI
NGT INTO SAT. THIS WEEKEND`S FCST IS RATHER UNCERTAIN...HINGING ON
THE INTERACTION BETWEEN NRN AND SRN STREAM S/WV`S. JUST WENT WITH
SLGT CHC/LOW CHC POPS FOR THIS PD.
TEMPS WILL BE WELL BLO NORMAL ON WED...A MODERATING TREND
AFTERWARDS AND WITH TEMPS RISING TO NEAR OR SLIGHTLY ABV SEASONAL
NORMS.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
VFR ACRS THE AREA THIS AFTN WITH BKN-OVC MID DECK. SCT --SHRA ACRS
CNTRL NY LATE THIS AFTN/EARLY EVNG BUT NO RESTRICTIONS XPCTD. LATER
TNGT...AREAS OF RAIN AND MVFR CIGS SPREAD INTO THE RGN IN THE
03-06Z TIME FRAME. WDSPRD IFR/MVFR TWDS DAYBREAK AND INTO TUE
AFTN. SHARP FNT WILL RESULT IN A TRANSITION TO SLEET LATE IN THE
PD AT SYR/ITH/ELM (BASED ON CRNT FNTL TIMING). IN ADDN...WE ARE
INDICATING POTNL FOR LLWS WITH FROPA BASED ON IMPRSV SHEAR
DISPLAYED IN THE MDL PROFILES. WINDS THIS AFTN SWLY 15-25...AND
SRLY TNGT 10-20 WITH HIGHER GUSTS...THEN BECMG NWLY 10-20 BEHIND
THE FNT AT WRN SITES.
OUTLOOK...
TUE NGT...SCT MVFR IN -SHSN CNTRL NY.
WED-THU-FRI...VFR.
FRI NGT/SAT...MVFR CIGS PSBL IN SELY FLOW OVER NE PA AND SRN NY.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...FLOOD WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR
NYZ009-037.
&&
$$
SYNOPSIS...MSE
NEAR TERM...BMW
SHORT TERM...MSE
LONG TERM...
AVIATION...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
324 PM EDT MON APR 14 2014
.SYNOPSIS...
VERY MILD WEATHER WILL CONTINUE TONIGHT WITH SCATTERED SHOWERS AND
TEMPERATURES ONLY FALLING INTO THE MID TO UPPER 50S. A STRONG COLD
FRONT WILL BRING A PERIOD OF HEAVY RAIN TO THE AREA ON TUESDAY...
FOLLOWED BY MUCH COLDER AIR AND A BRIEF CHANGE TO SNOW AND SLEET
BEFORE THE PRECIPITATION ENDS EARLY TUESDAY EVENING. WEDNESDAY
WILL BE UNSEASONABLY COLD... THE MILDER WEATHER WILL RETURN BY
LATE THIS WEEK.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
CLDS ARE INCRSNG ACRS THE FCST AREA UNDER WARM SWLY FLOW. AREA OF
-SHRA ACRS WRN NY AND PA WORKING NEWD BUT LOW LVL AIR MASS IS
PRETTY DRY. XPCT SCT --SHRA TO SPREAD INTO THE CNTRL SRN TIER AND
WRN FINGER LAKES BY LATE AFTN...SLOWLY SPREADING EWD. CRNT NEAR
TERM FCST REFLECTS THIS THINKING.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH TUESDAY NIGHT/...
A STRONG COLD FRONT WILL TRACK ACROSS THE AREA THROUGH THIS PERIOD
BRINGING A PERIOD OF HEAVY RAIN TO MUCH OF THE AREA ALONG WITH
RAPIDLY FALLING TEMPERATURES AND A LIKELY CHANGE-OVER TO SNOW AND
SLEET. DETAILS ARE GIVEN BELOW.
A BAND OF SCATTERED SHOWERS MOVING ACROSS THE AREA THIS EVENING
IS STILL WELL AHEAD OF THE COLD FRONT WHICH IS BACK TO THE WEST
AROUND DTW. THESE SHOWERS WILL TEND TO LIFT NORTHEAST AND WEAKEN
THROUGH THIS EVENING BUT THERE STILL APPEARS TO BE A GOOD CHANCE
FOR A ROUND OF SHOWERS THIS EVENING AS THIS SYSTEM MOVES ACROSS
THE AREA. LATEST RAP MODEL SOUNDINGS HARDLY INDICATING ANY CAPE
OVER THE AREA THIS EVENING AND HAVE LEFT OUT ANY THUNDER MENTION.
EXPECT A LULL IN THE ACTIVITY OVER NIGHT IN THE WAKE OF THIS
SYSTEM... BEFORE RAIN BEGINS TO INCREASE WITH THE APPROACH OF THE
COLD FRONT TOWARD DAYBREAK. IT WILL BE A VERY MILD NIGHT WITH
SOUTHERLY BREEZES AND LOW TEMPERATURES MOSTLY 55 TO 60... MORE
SEASONABLE FOR JUNE THAN MID-APRIL.
A STRONG COLD FRONT WILL TRACK SLOWLY EAST ACROSS THE CWA ON
TUESDAY. THIS FRONT WILL BE ACCOMPANIED BY STRONG RIGHT-REAR QUAD
UPPER DYNAMICS AND A 50 KT LOW-LEVEL SOUTHERLY JET. INSTABILITY
ALONG AND AHEAD OF THE FRONT WILL BE MINIMAL BUT CAN`T RULE OUT A
FEW RUMBLES OF THUNDER RIGHT WITH THE FRONTAL PASSAGE DURING
MIDDAY TUESDAY. AT THIS TIME WE ARE EXPECTING SHOWERS TO INCREASE AHEAD
OF THE FRONT EARLY TUESDAY... THEN A BAND OF MODERATE TO HEAVY
RAIN WILL LIKELY ACCOMPANY AND FOLLOW THE FRONTAL PASSAGE... LATE
TUESDAY MORNING OVER THE FINGER LAKES... AROUND NOON ALONG THE
I-81 CORRIDOR... AND EARLY AFTERNOON OVER THE WESTERN CATSKILLS.
SOME CONCERN THAT ANY BAND OF HEAVY RAIN THAT DEVELOPS ALONG THE
FRONT COULD BE HEAVY ENOUGH TO CAUSE SOME MINOR FLOODING ISSUES IF
HEAVY RAIN FALLS DURING A SHORT PERIOD. TOTAL RAINFALL WITH THE
SYSTEM IS EXPECTED TO BE IN THE 1 TO 1.5 INCH RANGE. HAVE HELD OFF
ON ANY WATCHES AT THIS POINT... BUT A WATCH MAY NEED CONSIDERATION
ONCE TIMING AN LOCATION OF ANY HEAVY RAIN BANDS BECOMES MORE
CERTAIN.
SOUTHWEST WINDS WILL INCREASE TONIGHT AS THE FRONT APPROACHES.
SOME GUSTS TO 30 OR 40 MPH WILL BE POSSIBLE OVER HIGHER TERRAIN
LATER TONIGHT WITH LIGHTER WINDS AT LOWER ELEVATIONS. NORTHWEST
WINDS WILL BE STRONG AND GUSTY BEHIND THE FRONT LATE TUESDAY INTO
TUESDAY NIGHT. SOME GUSTS OF 30 TO 40 MPH ARE POSSIBLE.
THIS WILL BE AN ANAFRONT WITH SEVERAL HOURS OF PRECIPITATION
LINGERING BEHIND THE FRONT. COLD AIR MOVES IN QUICKLY BEHIND THE
FRONT WITH RAIN CHANGING TO SLEET OR A MIX OF SLEET AND SNOW OVER
THE FINGER LAKES BY LATE MORNING... AND ALONG THE I-81 CORRIDOR BY
MID TO LATE AFTERNOON. MODELS ARE IN EXCELLENT AGREEMENT WITH THIS
SCENARIO AND INDICATE THE POTENTIAL FOR A WIDESPREAD 1 TO 3 INCHES
OF SNOW AND SLEET BY EARLY EVENING TUESDAY FOR MOST OF THE AREA.
STEADIER SNOW WILL END ACROSS THE AREA EARLY TUESDAY EVENING BUT
850 MB TEMPERATURES FALL TO AROUND -15 DEGREES C. DESPITE VERY DRY
AIR EXPECT THAT THIS SCEANRIO WILL SUPPORT A LITTLE BIT OF LAKE
EFFECT SNOW OVER CENTRAL NY TUESDAY EVENING. ANY ADDITIONAL
ACCUMULATIONS SHOULD BE LIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
QUIET WX IN THE MED RNG WITH HIGH PRES BUILDING INTO THE RGN ON
WED. AFTER SOME MRNG LAKE CLDS...MOSTLY SUNNY SKIES WILL PREVAIL.
FAIR AND DRY WEATHER PERSISTS INTO FRIDAY AS THE SFC HIGH SLIDES
OFF THE CST. WE COULD SEE CLDS RETURN IN THE SELY FLOW LATER FRI
NGT INTO SAT. THIS WEEKEND`S FCST IS RATHER UNCERTAIN...HINGING ON
THE INTERACTION BETWEEN NRN AND SRN STREAM S/WV`S. JUST WENT WITH
SLGT CHC/LOW CHC POPS FOR THIS PD.
TEMPS WILL BE WELL BLO NORMAL ON WED...A MODERATING TREND
AFTERWARDS AND WITH TEMPS RISING TO NEAR OR SLIGHTLY ABV SEASONAL
NORMS.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
VFR ACRS THE AREA THIS AFTN WITH BKN-OVC MID DECK. SCT --SHRA ACRS
CNTRL NY LATE THIS AFTN/EARLY EVNG BUT NO RESTRICTIONS XPCTD. LATER
TNGT...AREAS OF RAIN AND MVFR CIGS SPREAD INTO THE RGN IN THE
03-06Z TIME FRAME. WDSPRD IFR/MVFR TWDS DAYBREAK AND INTO TUE
AFTN. SHARP FNT WILL RESULT IN A TRANSITION TO SLEET LATE IN THE
PD AT SYR/ITH/ELM (BASED ON CRNT FNTL TIMING). IN ADDN...WE ARE
INDICATING POTNL FOR LLWS WITH FROPA BASED ON IMPRSV SHEAR
DISPLAYED IN THE MDL PROFILES. WINDS THIS AFTN SWLY 15-25...AND
SRLY TNGT 10-20 WITH HIGHER GUSTS...THEN BECMG NWLY 10-20 BEHIND
THE FNT AT WRN SITES.
OUTLOOK...
TUE NGT...SCT MVFR IN -SHSN CNTRL NY.
WED-THU-FRI...VFR.
FRI NGT/SAT...MVFR CIGS PSBL IN SELY FLOW OVER NE PA AND SRN NY.
&&
.FIRE WEATHER...
4 AM MONDAY UPDATE...
DEWPOINT TEMPERATURES WILL REMAIN FAIRLY STEADY THROUGH THE DAY
BUT TEMPERATURES ARE NOT EXPECTED TO CLIMB AS HIGH AS YESTERDAY,
LEADING TO MINIMUM RELATIVE HUMIDITY VALUES REMAINING ABOVE 40%
THROUGH THE DAY. SOUTH-SOUTHWEST WINDS WILL BE STRONG AND GUSTY
AGAIN TODAY BUT ANY FIRE WEATHER CONCERNS WILL BE PRECLUDED BY
INCREASING MOISTURE AHEAD OF AN APPROACHING COLD FRONT. WIDESPREAD
RAIN WILL MOVE IN LATE TONIGHT. COLD AIR WILL MOVE IN BEHIND THE
FRONT ON TUESDAY AFTERNOON, SWITCHING RAIN OVER TO SNOW SHOWERS
BRIEFLY ON TUESDAY NIGHT, MAINLY ACROSS CENTRAL NEW YORK.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...FLOOD WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR
NYZ009-037.
&&
$$
SYNOPSIS...MSE
NEAR TERM...RHB
SHORT TERM...MSE
LONG TERM...CMG
AVIATION...
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
321 PM EDT MON APR 14 2014
.SYNOPSIS...
VERY MILD WEATHER WILL CONTINUE TONIGHT WITH SCATTERED SHOWERS AND
TEMPERATURES ONLY FALLING INTO THE MID TO UPPER 50S. A STRONG COLD
FRONT WILL BRING A PERIOD OF HEAVY RAIN TO THE AREA ON TUESDAY...
FOLLOWED BY MUCH COLDER AIR AND A BRIEF CHANGE TO SNOW AND SLEET
BEFORE THE PRECIPITATION ENDS EARLY TUESDAY EVENING. WEDNESDAY
WILL BE UNSEASONABLY COLD... THE MILDER WEATHER WILL RETURN BY
LATE THIS WEEK.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
CLDS ARE INCRSNG ACRS THE FCST AREA UNDER WARM SWLY FLOW. AREA OF
-SHRA ACRS WRN NY AND PA WORKING NEWD BUT LOW LVL AIR MASS IS
PRETTY DRY. XPCT SCT --SHRA TO SPREAD INTO THE CNTRL SRN TIER AND
WRN FINGER LAKES BY LATE AFTN...SLOWLY SPREADING EWD. CRNT NEAR
TERM FCST REFLECTS THIS THINKING.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH TUESDAY NIGHT/...
A STRONG COLD FRONT WILL TRACK ACROSS THE AREA THROUGH THIS PERIOD
BRINGING A PERIOD OF HEAVY RAIN TO MUCH OF THE AREA ALONG WTIH
RAPIDLY FALLING TEMPERATURES AND A LIKELY CHANGE-OVER TO SNOW AND
SLEET. DETAILS ARE GIVEN BELOW.
BAND OF SCATTERED SHOWERS MOVING ACROSS THE AREA THIS EVNEING ARE
STILL WELL AHEAD OF THE COLD FRONT WHICH IS BACK TO THE WEST
AROUND DTW. THESE SHOWERS WILL TEND TO LIFT NORTHEAST AND WEAKEN
THROUGH THIS EVENING BUT THERE STILL APPEARS TO BE A GOOD CHANCE
FOR A ROUND OF SHOWERS THIS EVENING AS THIS SYSTEM MOVES ACROSS
THE AREA. LATEST RAP MODEL SOUNDINGS HARDLY INDICATING ANY CAPE
OVER THE AREA THIS EVENING AND HAVE LEFT OUT ANY THUNDER MENTION.
EXPECT A LULL IN THE ACTIVITY OVER NIGHT IN THE WAKE OF THIS
SYSTEM... BEFORE RAIN BEGINS TO INCREASE WITH THE APPROACH OF THE
COLD FRONT TOWARD DAYBREAK. IT WILL BE A VERY MILD NIGHT WITH
SOUTHERLY BREEZES AND LOW TEMPERATURES MOSTLY 55 TO 60... MORE
SEASONABLE FOR JUNE THAN MID-APRIL.
A STRONG COLD FRONT WILL TRACK SLOWLY EAST ACROSS THE CWA ON
TUESDAY. THIS FRONT WILL BE ACCOMPANIED BY STRONG RIGHT-REAR QUAD
UPPER DYNAMICS AND A 50 KT LOW-LEVEL SOUTHERLY JET. INSTABILITY
ALONG AND AHEAD OF THE FRONT WILL BE MINIMAL BUT CAN`T RULE OUT A
FEW RUMBLES OF THUNDER RIGHT WITH THE FRONTAL PASSAGE DURING
MIDDAY TUESDAY. AT THIS TIME WE ARE EXPECTING SHOWERS TO INCREASE AHEAD
OF THE FRONT EARLY TUESDAY... THEN A BAND OF MODERATE TO HEAVY
RAIN WILL LIKELY ACCOMPANY AND FOLLOW THE FRONTAL PASSAGE... LATE
TUESDAY MORNING OVER THE FINGER LAKES... AROUND NOON ALONG THE
I-81 CORRIDOR... AND EARLY AFTERNOON OVER THE WESTERN CATSKILLS.
SOME CONCERN THAT ANY BAND OF HEAVY RAIN THAT DEVELOPS ALONG THE
FRONT COULD BE HEAVY ENOUGH TO CAUSE SOME MINOR FLOODING ISSUES IF
HEAVY RAIN FALLS DURING A SHORT PERIOD. TOTAL RAINFALL WITH THE
SYSTEM IS EXPECTED TO BE IN THE 1 TO 1.5 INCH RANGE. HAVE HELD OFF
ON ANY WATCHES AT THIS POINT... BUT A WATCH MAY NEED CONSIDERATION
ONCE TIMING AN LOCATION OF ANY HEAVY RAIN BANDS BECOMES MORE
CERTAIN.
SOUTHWEST WINDS WILL INCREASE TONIGHT AS THE FRONT APPROACHES.
SOME GUSTS TO 30 OR 40 MPH WILL BE POSSIBLE OVER HIGHER TERRAIN
LATER TONIGHT WITH LIGHTER WINDS AT LOWER ELEVATIONS. NORTHWEST
WINDS WILL BE STRONG AND GUSTY BEHIND THE FRONT LATE TUESDAY INTO
TUESDAY NIGHT. SOME GUSTS OF 30 TO 40 MPH ARE POSSIBLE.
THIS WILL BE AN ANAFRONT WITH SEVERAL HOURS OF PRECIPITATION
LINGERING BEHIND THE FRONT. COLD AIR MOVES IN QUICKLY BEHIND THE
FRONT WITH RAIN CHANGING TO SLEET OR A MIX OF SLEET AND SNOW OVER
THE FINGER LAKES BY LATE MORNING... AND ALONG THE I-81 CORRIDOR BY
MID TO LATE AFTERNOON. MODELS ARE IN EXCELLENT AGREEMENT WITH THIS
SCENARIO AND INDICATE THE POTENTIAL FOR A WIDESPREAD 1 TO 3 INCHES
OF SNOW AND SLEET BY EARLY EVENING TUESDAY FOR MOST OF THE AREA.
STEADIER SNOW WILL END ACROSS THE AREA EARLY TUESDAY EVENING BUT
850 MB TEMPERATURES FALL TO AROUND -15 DEGREES C. DESPITE VERY DRY
AIR EXPECT THAT THIS SCEANRIO WILL SUPPORT A LITTLE BIT OF LAKE
EFFECT SNOW OVER CENTRAL NY TUESDAY EVENING. ANY ADDITIONAL
ACCUMULATIONS SHOULD BE LIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
QUIET WX IN THE MED RNG WITH HIGH PRES BUILDING INTO THE RGN ON
WED. AFTER SOME MRNG LAKE CLDS...MOSTLY SUNNY SKIES WILL PREVAIL.
FAIR AND DRY WEATHER PERSISTS INTO FRIDAY AS THE SFC HIGH SLIDES
OFF THE CST. WE COULD SEE CLDS RETURN IN THE SELY FLOW LATER FRI
NGT INTO SAT. THIS WEEKEND`S FCST IS RATHER UNCERTAIN...HINGING ON
THE INTERACTION BETWEEN NRN AND SRN STREAM S/WV`S. JUST WENT WITH
SLGT CHC/LOW CHC POPS FOR THIS PD.
TEMPS WILL BE WELL BLO NORMAL ON WED...A MODERATING TREND
AFTERWARDS AND WITH TEMPS RISING TO NEAR OR SLIGHTLY ABV SEASONAL
NORMS.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
VFR ACRS THE AREA THIS AFTN WITH BKN-OVC MID DECK. SCT --SHRA ACRS
CNTRL NY LATE THIS AFTN/EARLY EVNG BUT NO RESTRICTIONS XPCTD. LATER
TNGT...AREAS OF RAIN AND MVFR CIGS SPREAD INTO THE RGN IN THE
03-06Z TIME FRAME. WDSPRD IFR/MVFR TWDS DAYBREAK AND INTO TUE
AFTN. SHARP FNT WILL RESULT IN A TRANSITION TO SLEET LATE IN THE
PD AT SYR/ITH/ELM (BASED ON CRNT FNTL TIMING). IN ADDN...WE ARE
INDICATING POTNL FOR LLWS WITH FROPA BASED ON IMPRSV SHEAR
DISPLAYED IN THE MDL PROFILES. WINDS THIS AFTN SWLY 15-25...AND
SRLY TNGT 10-20 WITH HIGHER GUSTS...THEN BECMG NWLY 10-20 BEHIND
THE FNT AT WRN SITES.
OUTLOOK...
TUE NGT...SCT MVFR IN -SHSN CNTRL NY.
WED-THU-FRI...VFR.
FRI NGT/SAT...MVFR CIGS PSBL IN SELY FLOW OVER NE PA AND SRN NY.
&&
.FIRE WEATHER...
4 AM MONDAY UPDATE...
DEWPOINT TEMPERATURES WILL REMAIN FAIRLY STEADY THROUGH THE DAY
BUT TEMPERATURES ARE NOT EXPECTED TO CLIMB AS HIGH AS YESTERDAY,
LEADING TO MINIMUM RELATIVE HUMIDITY VALUES REMAINING ABOVE 40%
THROUGH THE DAY. SOUTH-SOUTHWEST WINDS WILL BE STRONG AND GUSTY
AGAIN TODAY BUT ANY FIRE WEATHER CONCERNS WILL BE PRECLUDED BY
INCREASING MOISTURE AHEAD OF AN APPROACHING COLD FRONT. WIDESPREAD
RAIN WILL MOVE IN LATE TONIGHT. COLD AIR WILL MOVE IN BEHIND THE
FRONT ON TUESDAY AFTERNOON, SWITCHING RAIN OVER TO SNOW SHOWERS
BRIEFLY ON TUESDAY NIGHT, MAINLY ACROSS CENTRAL NEW YORK.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...FLOOD WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR
NYZ009-037.
&&
$$
SYNOPSIS...MSE
NEAR TERM...RHB
SHORT TERM...MSE
LONG TERM...CMG
AVIATION...
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS RALEIGH NC
302 PM EDT MON APR 14 2014
.SYNOPSIS...A WARM MOIST SOUTHERLY FLOW WILL INCREASE OVER THE AREA
THROUGH TONIGHT. A COLD FRONT WILL APPROACH THE MOUNTAINS FROM
THE WEST LATE TONIGHT... THEN PROGRESS EAST ACROSS THE CAROLINAS
TUESDAY AFTERNOON AND EVENING. COOL HIGH PRESSURE WILL EXTEND INTO
THE AREA FROM THE NORTH WEDNESDAY THROUGH THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM MONDAY...
AS PRECIPITABLE WATER VALUES HAVE CLIMBED TO NEAR AN INCH...AND
INSTABILITY HAS INCREASED DURING THE DAY WITH MSAS SHOWING LIFTED
INDICES AROUND -2C AND MLCAPE ON THE SPC MESOANALYSIS A COUPLE OF
HUNDRED J/KG...A FEW SHOWERS HAVE DEVELOPED OVER THE PIEDMONT IN
UPPER DIFFLUENCE AS A MODEST MID-LEVEL SHORTWAVE MOVES THROUGH. THE
LATEST HRRR WRF IS HANDLING THE LOCATION...COVERAGE...AND INTENSITY
OF THESE SHOWERS FAIRLY WELL...AND THOUGH AN ISOLATED THUNDERSTORM
IS POSSIBLE...MOSTLY THE RELATIVELY DEEP CONVECTION SHOULD REMAIN AS
SHOWERS. OVERNIGHT...A GRADUAL INCREASE IN MOISTURE CONTINUES...WITH
PRECIPITABLE WATER VALUES INCREASING TO NEAR 1.5 INCHES BY 12Z
TUESDAY AS 850MB THETA-E VALUES INCREASE AS WELL. MID-LEVEL
SHORTWAVES MOVING TOWARD CENTRAL NORTH CAROLINA SHOULD WEAKEN AS
THEY APPROACH...AND THE NAM IN PARTICULAR FORECASTS 850MB LIFT TO
DECREASE...BUT 850MB WINDS INCREASE LATE TONIGHT WHICH SHOULD ADD TO
MOISTURE TRANSPORT AND LIFT...AND 0-3KM SHEAR INCREASES AS WELL TO
AROUND 40KT PARTICULARLY IN THE SOUTHWEST PIEDMONT LATE. ALREADY...
THE COVERAGE OF SHOWERS HAS INCREASED TOWARD THE FOOTHILLS...AND
GRADUALLY DURING THE EVENING AND OVERNIGHT HOURS THE COVERAGE OF
NUMEROUS OR GREATER SHOWERS AND ISOLATED THUNDERSTORMS SHOULD MOVE
EAST ACROSS CENTRAL NORTH CAROLINA.
THROUGH MIDNIGHT...THE AREA WITH BETTER COVERAGE OF SHOWERS SHOULD
BE OVER THE FAR WESTERN PIEDMONT...THEN OVERNIGHT...EXPECT BETTER
COVERAGE GRADUALLY EASTWARD. AS WINDS ALOFT INCREASE...AN ISOLATED
STRONG STORM CANNOT BE RULED OUT...ESPECIALLY OVER THE SOUTHWEST
PIEDMONT WHERE THE COMBINATION OF SHEAR AND 850MB WINDS AND LIFT IS
EXPECTED TO BE BEST OVERNIGHT. ALSO...IT IS INTERESTING THAT THE NAM
MOS GUIDANCE FORECASTS SUSTAINED WINDS TO 25KT AT KGSO AND EVEN THE
GFS FORECASTS SUSTAINED SURFACE WINDS TO JUST BELOW 20KT LATE
TONIGHT. A FEW DECENT GUSTS ARE POSSIBLE...IT WOULD SEEM...AS ANY
HEAVIER SHOWER MOVES THROUGH OVERNIGHT. AROUND AND JUST AFTER 06Z...
THE GFS BUFR SOUNDINGS SHOW A MOIST ADIABATIC PROFILE AT KGSO WITH
WINDS JUST OFF THE SURFACE TO 40KT...AND THE NAM...WHILE
DRIER...DOES HAVE A SLIGHTLY STEEPER LAPSE RATE. OVERNIGHT LOWS
SHOULD BE WARM...IN THE LOWER TO MID 60S AHEAD OF THE FRONT.
&&
.SHORT TERM /TUESDAY AND TUESDAY NIGHT/...
AS OF 300 PM MONDAY...
WEAKENING LIFT BUT WITH INCREASING 0-3KM SHEAR MOVES EAST ACROSS
CENTRAL NORTH CAROLINA EARLY TUESDAY...THEN THERE IS FORECAST A
BRIEF RESPITE IN THE CHANCES FOR SHOWERS AROUND MID-MORNING WITH A
SLIGHT DECREASE IN 850MB THETA-E VALUES AND INSTABILITY. AS THE
AFTERNOON APPROACHES...850MB WINDS SHOULD INCREASE TO 50 TO 55KT AS
A 120KT 300MB JET MOVES THROUGH THE AREA...COINCIDENT WITH THE RIGHT
ENTRANCE REGION OF A 90KT 500MB JET. WHILE 1000-500MB LAPSE RATES
ARE ONLY FORECAST AROUND 6C/KM...AND THOSE MAINLY EAST OF U.S. 1...
MUCAPE THAT INCREASES OVERNIGHT TO NEARLY 1000J/KG ON THE NAM OVER
THE FAR SOUTHWEST PIEDMONT CONTINUES TO PUSH ACROSS CENTRAL NORTH
CAROLINA WITH VALUES FROM 1000-1500J/KG DURING TUESDAY. 0-3KM SHEAR
IS ON THE ORDER OF 40-50KT TUESDAY AFTERNOON...INCREASING FURTHER
TOWARD THE INTERSTATE 95 CORRIDOR LATE. MODEST LAPSE RATES IN A
BROADLY MOIST AIR MASS SHOULD HELP TO LIMIT AVAILABLE INSTABILITY...
BUT SYSTEM DYNAMICS ALONG AND AHEAD OF THE FRONT COULD COMPENSATE
FOR THIS AND MAKE FOR THE POTENTIAL FOR ISOLATED SEVERE STORMS
TUESDAY. IF A LOCATION SEEMED TO HAVE A BETTER CHANCE OF ISOLATED
SEVERE STORMS...IT WOULD SEEM TO BE ALONG AND EAST OF U.S. 1 WHERE
THE OVERALL INSTABILITY AND SHEAR WILL BE BETTER TUESDAY
AFTERNOON...AS LIFTED INDICES THERE SHOULD BE -2C TO -4C...WITH
BETTER HEATING EXPECTED. THE PRIMARY SEVERE THREAT IS ANTICIPATED TO
BE WIND...BUT WITH 0-3KM HELICITY VALUES FROM 100-300 M2/S2...AN
ISOLATED TORNADO CANNOT BE RULED OUT. HIGHS WERE LEANED TOWARD THE
WARMER MAV GUIDANCE ANTICIPATING A BREAK IN PRECIPITATION DURING THE
MORNING...UPPER 60S NORTHWEST TO AROUND 80 SOUTHEAST.
STRONG COLD AIR ADVECTION TAKES PLACE TUESDAY NIGHT AS HIGH PRESSURE
MOVES IN. ONCE THE STRONG MID-LEVEL TROUGH MOVES THROUGH THE THREAT
OF PRECIPITATION SHOULD END...THEN IMPACTS TURN TOWARD THE POTENTIAL
FOR FREEZING CONDITIONS. THE GUIDANCE HAS BEEN CONSISTENT
FORECASTING LOWS AT OR BELOW FREEZING FOR A COUPLE OF RUNS MAINLY
ALONG AND WEST OF INTERSTATE 95...AND WHILE WINDS IN MANY LOCATIONS
SHOULD STAY UP THROUGH A LARGE PART OF THE NIGHT IN A TIGHT GRADIENT
BEHIND THE COLD FRONT AS THE HIGH BUILDS IN...LATE AT NIGHT THERE
SHOULD BE JUST ENOUGH WIND REDUCTION IN COMBINATION WITH SIMPLE
ADVECTION TO RESULT IN SEVERAL AREAS WITH TEMPERATURES BELOW
FREEZING. WILL ISSUE A FREEZE WATCH FOR A LARGE PART OF CENTRAL
NORTH CAROLINA FOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING...
KEEPING OUT THE IMMEDIATE INTERSTATE 95 CORRIDOR FOR NOW DUE TO
GREATER WIND AND MIXING EXPECTED THERE. LOWS TUESDAY NIGHT 29 TO 32
MOSTLY FROM U.S. 1 WEST...33 TO 37 IN THE INTERSTATE 95 CORRIDOR.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...
FOR WED THROUGH THU NIGHT: THE INTENSE BUT DAMPENING TROUGH WILL
TRACK QUICKLY TO OUR NORTHEAST IN THE PREDAWN HOURS WED...AND WILL
BE FOLLOWED BY GENERALLY FLAT SW FLOW OVER THE SOUTHEAST/MIDSOUTH/
CAROLINAS THROUGH WED. FORECAST SOUNDINGS ARE VERY DRY AND STABLE AS
THE CENTER OF THE COOL SURFACE HIGH PRESSURE MOVES FROM THE OHIO
VALLEY NORTHEASTWARD OVER THE ST LAWRENCE VALLEY WHILE NOSING DOWN
THROUGH NC. EXPECT BREEZY AND COOL WINDS FROM THE NE WED...
DIMINISHING LATE WED INTO THU AS THE MSLP GRADIENT RELAXES. LOW
LEVEL THICKNESSES ARE EXPECTED TO PLUNGE TUE NIGHT TO OVER 70 M
BELOW NORMAL...WITH ONLY MODEST RECOVERY DURING THE DAY...
TRANSLATING TO HIGHS IN THE LOW-MID 50S. (AND THIS MAY EVEN BE
OPTIMISTIC CONSIDERING THE PROJECTED 925 MB TEMPS BROUGHT DOWN DRY
ADIABATICALLY YIELD HIGHS ONLY AROUND 50 OVER MUCH OF CENTRAL NC.)
EXPECT MOSTLY CLEAR SKIES TO CONTINUE THROUGH THU NIGHT WITH DEEP
DRY/STABLE AIR AS THE SLOWLY RETREATING AND MODIFYING SURFACE RIDGE
NOSES INTO NC FROM THE NORTH... ALTHOUGH WE COULD START TO SEE
PATCHY STRATUS LATE THU NIGHT WITH INCREASING ONSHORE-DIRECTED FLOW.
LIGHT WINDS AND A CONTINUED ANOMALOUSLY COOL AIR MASS WILL FOSTER
GOOD RADIATIONAL COOLING CONDITIONS... AND ANOTHER LIGHT FREEZE IS
POSSIBLE WED NIGHT... PARTICULARLY IN THE RURAL AREAS OF THE
PIEDMONT. NOT QUITE AS COOL THU WITH HIGHS EXPECTED TO BE 59-64.
LOWS THU NIGHT 37-42 WITH RISING DEW POINTS.
FOR FRI THROUGH MON: LONGWAVE TROUGHING THAT DRIFTS EAST ACROSS
CENTRAL NOAM THU IS EXPECTED TO AMPLIFY SLIGHTLY AS IT HEADS
EASTWARD INTO ERN NOAM FRI/SAT. THE APPROACH OF THIS TROUGH IS
EXPECTED TO DRAW ENERGY FROM THE NRN GULF TOWARD THE NE... INDUCING
SURFACE CYCLOGENESIS OVER THE NE GULF OR FL... WHICH WOULD THEN
TRACK NORTHEASTWARD OVER OR JUST OFF THE SOUTHEAST COAST FRI
NIGHT/SAT. THE GFS IS FAIRLY DRY HERE... HOLDING ITS SRN STREAM
PRECIP TO OUR SE AND ANY NRN STREAM PRECIP TO OUR NORTH. THE ECMWF
IS STRONGER WITH THE SOUTHERN WAVE... DEEPENING IT OVER SRN GA AND
FL... BUT IT TOO HOLDS MOST OF THE PRECIP WITH THIS WAVE TO OUR SE.
WILL RETAIN THE BASIC STRUCTURE OF THE PRECIP CHANCES WE CURRENTLY
HAVE IN THERE... BUT REDUCE THEM AND CONFINE THE BETTER POPS TO OUR
SOUTHEAST SECTIONS. AFTER BOTH THE NORTHERN AND SOUTHERN TROUGHS
SHIFT EAST OF OUR LONGITUDE LATE SAT INTO SAT NIGHT... MID LEVEL
RIDGING OVERSPREADS THE GULF/MIDSOUTH INTO THE SOUTHEAST AS ANOTHER
HIGH PRESSURE BRIEFLY BUILDS IN FROM THE NORTH ON SUNDAY. EXPECT
DECREASING CLOUDS SAT NIGHT AND A GOOD BIT OF SUNSHINE EASTER SUNDAY
WITH MODERATING TEMPS CLOSE TO SEASONAL NORMALS. LOW CONFIDENCE IN
MONDAY`S FORECAST AS THE GFS DEEPENS A MID LEVEL LOW OVER THE LOWER
GREAT LAKES... LEADING TO SURFACE LOW FORMATION ALONG A ROUGHLY E-W
FRONT ACROSS THE REGION WITH WIDESPREAD RAIN MOVING IN... WHILE THE
ECMWF IS MUCH WEAKER/SLOWER AND KEEPS NC DRY MON. WILL GO WITH THE
WEAKER ECMWF SOLUTION AND KEEP MONDAY DRY FOR NOW... BUT STAY TUNED.
EXPECT TEMPS CLOSE TO NORMAL MON.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 155 PM MONDAY...
ASIDE FROM A THREAT OF BKN MVFR CIGS NEAR INT/GSO EARLY IN THE TAF
PERIOD FROM 18Z-20Z TODAY... A PERIOD OF CONTINUED PREVAILING VFR
CONDITIONS EXPECTED THIS AFTERNOON INTO EARLY EVENING (THROUGH
AROUND 02Z OR 03Z)... WITH WINDS FROM THE SOUTH AT 8-15 KTS
SPORADICALLY GUSTING TO 15-20 KTS... AND VFR CIGS. PATCHY SHOWERS
MAY OCCUR PRIMARILY AT FAY... BUT ARE UNLIKELY TO LAST ANY MORE THAN
15 MIN AT ANY ONE TIME. AVIATION CONDITIONS ARE EXPECTED TO
DETERIORATE THIS EVENING... AROUND 02Z OR 03Z... WITH CIGS DROPPING
TO MVFR THEN FAIRLY QUICKLY TO IFR IN THE 04Z-06Z TIME FRAME... WITH
CONTINUED STOUT WINDS FROM THE SOUTH AND SSW (FROM 180-210 DEGREES)
STRENGTHENING TO AROUND 14-17 KTS GUSTING TO 20-25 KTS OVERNIGHT.
EXPECT ON-AND-OFF MAINLY MVFR-VSBY-PRODUCING SHOWERS FROM THIS 04Z-
06Z TIME FRAME THROUGH AROUND 11Z-13Z. WINDS WILL REMAIN BLUSTERY
FROM THE SSW THROUGH THE END OF THE TAF VALID PERIOD... POTENTIALLY
INDUCING MECHANICAL TURBULENCE... BUT A LULL IN SHOWERS IS THEN
EXPECTED FROM THIS 11Z-13Z WINDOW LASTING A FEW HOURS. CIGS MAY RISE
A BIT TO MVFR DURING THIS RELATIVE LULL IN PRECIP. HOWEVER... AS A
STRONG COLD FRONT APPROACHES FROM THE WEST... INT/GSO MAY SEE
WIDESPREAD SHOWERS/STORMS MOVING IN TOWARD THE END OF THE TAF VALID
PERIOD (AFTER 16Z).
LOOKING BEYOND 18Z TUE: WIDESPREAD SHOWERS AND STORMS GENERATING IFR
CONDITIONS WILL SPREAD WEST TO EAST ACROSS CENTRAL NC FROM 18Z
THROUGH 06Z... AS A STRONG COLD FRONT CROSSES THE STATE. STRONG
WINDS FROM THE SSW AND SW WILL SHIFT ABRUPTLY TO BE FROM THE NW TUE
AFTERNOON. HIGH CONFIDENCE IN CLEARING SKIES AND VFR CONDITIONS POST-
FRONT AFTER MIDNIGHT TUE NIGHT LASTING THROUGH THU EVENING. THERE IS
A CHANCE OF SHALLOW LOW STRATUS LATE THU NIGHT/EARLY FRI MORNING...
THEN A BETTER CHANCE OF THICKER LOW STRATUS FRI NIGHT THROUGH NOON
SAT AHEAD OF THE NEXT STORM SYSTEM MOVING IN FROM THE SOUTH. -GIH
&&
.CLIMATE...
THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING...
AND THE RECORD LOW MAXIMUM TEMPERATURES FOR WED:
WED 04/16 THU 04/17
LOW/YEAR LOW MAX/YEAR LOW/YEAR
FAY: 28/1943 56/1950 31/1953
GSO: 25/1943 48/1929 29/1953
RDU: 28/1950 46/1890 29/1962
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING
FOR NCZ007>010-021>026-038>041-073>077-083-084.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...DJF
SHORT TERM...DJF
LONG TERM...HARTFIELD
AVIATION...HARTFIELD
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
155 PM EDT MON APR 14 2014
.SYNOPSIS...A WARM MOIST SOUTHERLY FLOW WILL INCREASE OVER THE AREA
THROUGH TONIGHT. A COLD FRONT WILL APPROACH THE MOUNTAINS FROM
THE WEST LATE TONIGHT... THEN PROGRESS EAST ACROSS THE CAROLINAS
TUESDAY AFTERNOON AND EVENING. COOL HIGH PRESSURE WILL EXTEND INTO
THE AREA FROM THE NORTH WEDNESDAY THROUGH THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1055 AM MONDAY...
THE 12Z KGSO SOUNDING WAS CAPPED TO DEEP CONVECTION WITH A GOOD CAP
BETWEEN 850MB AND 700MB...AND CONSIDERABLE MOISTURE ABOVE 500MB. THE
LATEST SPC MESOANALYSIS SHOWED A RELATIVE MINIMUM OF PRECIPITABLE
WATER VALUES OVER MUCH OF CENTRAL NORTH CAROLINA ALTHOUGH WITH A
NARROW RIBBON OF INCREASING VALUES...JUST BELOW AN INCH...EXTENDING
FROM SOUTH CAROLINA INTO THE SOUTHWEST PIEDMONT. HIGH PRESSURE
EXTENDING OVER CENTRAL NORTH CAROLINA FROM THE EAST WAS PROVIDING A
MOIST...SOUTHERLY FLOW OFF OF THE ATLANTIC INTO THE AREA...WITH
SURFACE DEW POINTS IN THE MID 50S TO AROUND 60.
TO OUR WEST...THE SURFACE LOW WILL INCREASE IN STRENGTH DUE TO THE
OFFSET UPPER LEVEL TROUGH TO THE WEST. DIVERGENCE ALOFT IS
DECREASING THE SURFACE PRESSURE AHEAD OF THE FRONT BRINGING IN
CYCLONIC VORTICITY ADVECTION IN A SHORT WAVE AHEAD OF THE FRONT.
SURFACE WINDS ARE SOUTHERLY AND HAVE INCREASED THE DEWPOINTS AS
MOIST AND WARM AIR IS ADVECTED INTO THE AREA AHEAD OF THE COLD
FRONT. WARM ADVECTION ALONG WITH CYCLONIC VORTICITY ADVECTION WILL
BRING AN INCREASE IN LIFT AND CLOUD COVER OVER THE AREA AND AN
INCREASED CHANCE FOR PRECIPITATION AND CONVECTION. A FEW SHOWERS ARE
POPPING UP TO OUR WEST AND ARE EXPECTED TO INCREASE IN NUMBER AND
EVENTUALLY PRODUCE CONVECTIVE STORMS AS THE COLD FRONT MOVES
EASTWARD.
THE 12Z UPPER-AIR ANALYSIS SHOWED SOME DIFFLUENCE TO OUR WEST AND
THIS IS FORECAST TO CONTINUE THIS AFTERNOON INTO TONIGHT AS A SERIES
OF MID-LEVEL WAVES MOVE THROUGH CENTRAL NORTH CAROLINA. THE LATEST
RAP SHOWS THE MID-LEVEL CAP WEAKENING WITH TIME THROUGH EARLY
AFTERNOON...AND SLIGHT 700MB COOLING ON THE 12Z UPPER-AIR ANALYSIS
WOULD SUGGEST THIS...ALTHOUGH THE RAP ALSO FORECASTS A MODEST
INCREASE IN THOSE MID-LEVEL TEMPERATURES LATE IN THE DAY. WITH THE
MOISTURE IN PLACE...MODEST INSTABILITY WITH SURFACE-BASED CAPE
AROUND 400J/KG AND MLCAPE IN THHIGHS TODAY WERE LOWERED ABOUT A
DEGREE IN THE TRIAD DUE TO EXPECTED CLOUD COVER...AND RAISED ABOUT A
DEGREE TOWARD INTERSTATE 95 DUE TO THINNER CLOUDS FOR A LONGER
PERIOD OF TIME THERE. E LOWEST KM AROUND 200J/KG...AND SOME LIFT
WITH THE MID-LEVEL SHORTWAVES...AS THE CAP ERODES ANTICIPATE
ISOLATED TO SCATTERED SHOWERS DEVELOPING...WITH AN ISOLATED
THUNDERSTORM POSSIBLE. AS THE MID-LEVEL TEMPERATURES WARM SLIGHTLY
LATER...THIS COULD FOR A TIME INHIBIT MORE DEEP CONVECTION...AND
THIS SCENARIO IS NOTED BY MORE THAN ONE WRF MODEL AS WELL AS IMPLIED
BY RAP QPF.
MOISTENING OF THE UPPER LEVELS WILL INCREASE CLOUD DEPTH AND ALLOW
FOR LIFTING OVER A DEEPER LAYER. THIS WILL INCREASE THE CHANCE FOR
SOME DEEP MOIST CONVECTION AND SHOWERS OVER THE AREA...
HOWEVER...THE STRONGEST LIFTING WILL STAY TO THE WEST WITH THE COLD
FRONT. CONVECTION SHOULD BECOME MORE NUMEROUS IN COVERAGE OVER
CENTRAL NORTH CAROLINA THIS EVENING INTO TONIGHT DUE TO ONGOING
MOISTENING...STRENGTHENING HEIGHT FALLS...AND PERIODIC DPVA IN SW
FLOW ALOFT...ESPECIALLY IN WESTERN PORTIONS OF THE STATE.
HOWEVER...SEVERAL LARGE MESOSCALE CONVECTIVE SYSTEMS ARE EXPECTED TO
DEVELOP UPSTREAM IN THE DEEP SOUTH IN THIS PERIOD...ONE THIS
AFTERNOON AND PERHAPS ANOTHER LATE TONIGHT...AND HOW THESE FEATURES
EVOLVE/INTERACT WITH THE LARGER SCALE PATTERN WILL MOST CERTAINLY
AFFECT PRECIP CHANCES DOWNSTREAM IN CENTRAL NC...LENDING A FAIR
AMOUNT OF UNCERTAINTY TO THE PRECISE COVERAGE/AMOUNT OF CONVECTION
TONIGHT.
THE INCREASED CLOUD COVER WILL RESULT IN A SLIGHT DECREASE...ROUGHLY
A DEGREE...FOR HIGH TEMPERATURES FOR THE WESTERN PART OF CENTRAL
NORTH CAROLINA. HIGHS WERE RAISED ABOUT A DEGREE TOWARD INTERSTATE
95 WHERE THERE WILL BE MORE PERIODS OF THINNER CLOUDS AND MORE
SUNLIGHT HITTING THE GROUND. A VERY MOIST AND BREEZY SOUTHERLY FLOW
THROUGHOUT THE WARM SECTOR IN THE CAROLINAS WILL MAINTAIN TEMPS IN
THE MID 60S OVERNIGHT.
THOUGH QUITE CONDITIONAL/UNCERTAIN...IF DEEP CONVECTION DEVELOPS AND
PROGRESSES INTO CENTRAL NC THIS EVENING AND TONIGHT...AN ISOLATED
SEVERE STORM WOULD BE POSSIBLE GIVEN INCREASINGLY IMPRESSIVE
LOW/DEEP-LAYER SHEAR.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
AS OF 330 AM MONDAY...
TUE/TUE NIGHT: EXPECT CHANCES FOR CONVECTION NEAR 100% ON TUESDAY AS
A POTENT UPPER LEVEL TROUGH AND ATTENDANT COLD FRONT PROGRESS
THROUGH THE CAROLINAS IN THE PRESENCE OF A MOIST AND UNSTABLE
AIRMASS VIA PERSISTENT SOUTHERLY LOW-LEVEL FLOW OFF THE ATLANTIC. AT
THIS TIME...FROPA IS EXPECTED TO OCCUR BETWEEN 18-21Z IN THE NW
PIEDMONT AND BY 00-03Z IN THE COASTAL PLAIN...WITH STRONG COLD
ADVECTION THEREAFTER. EXPECT HIGHS RANGING FROM THE MID/UPPER 60S IN
THE NW PIEDMONT WHERE CLOUD COVER/CONVECTION WILL PREVENT MUCH OF A
RISE IN TEMPS PRIOR TO FROPA...TO THE MID/UPPER 70S POTENTIALLY IN
THE COASTAL PLAIN WHERE FROPA WILL BE LATER. STRONG LOW/DEEP LAYER
SHEAR...FAVORABLE DIURNAL TIMING...AND MARGINAL TO MODERATE
DESTABILIZATION (500-1000 J/KG MLCAPE) CERTAINLY INDICATE A
POTENTIAL FOR SEVERE THUNDERSTORMS...THOUGH THE PRECISE NATURE OF
THE THREAT IS STILL DIFFICULT TO ASCERTAIN GIVEN A POTENTIAL FOR
UPSTREAM CONVECTION /MCS ACTIVITY/ LATE TONIGHT AND TUE MORNING.
DAMAGING WINDS AND ISOLD TORNADOES WILL BE THE PRIMARY THREAT(S)...
THE LATTER OF WHICH COULD BE FURTHER ENHANCED BY BACKED SFC WINDS
/LARGE CLOCKWISE CURVED HODOGRAPHS/ POSSIBLE ON THE EASTERN
PERIPHERY OF ANY SFC WAVES WHICH COULD DEVELOP ALONG THE FRONT IN
CENTRAL/EASTERN NC...PARTICULARLY ALONG AND EAST OF I-95 WHERE
DIURNAL TIMING AND DESTABILIZATION WILL BE MOST FAVORABLE. STRONG
COLD ADVECTION WILL RESULT IN A STARK CONTRAST IN TEMPERATURES IN
COMPARISON TO THE PREVIOUS FEW DAYS...WITH LOWS RANGING FROM THE
LOWER TO UPPER 30S...POTENTIALLY NEAR FREEZING ALONG/WEST OF HWY 1.
A FREEZE WATCH MAY BE NEEDED FOR PORTIONS OF THE AREA TUE NIGHT/WED
MORNING. SINCE LOWS WILL PRIMARILY DEPEND UPON COLD ADVECTION...
SUFFICIENT UNCERTAINTY EXISTS TO PRECLUDE ANY FROST/FREEZE PRODUCT
ISSUANCE AT THIS TIME. -VINCENT
AS OF 245 AM MONDAY...RISING HEIGHTS ALOFT/DNVA AND ASSOCIATED
STRONG SUBSIDENCE WILL RESULT IN FURTHER DEEP LAYER DRYING
WED...FOLLOWED BY GENERALLY NEUTRAL VERTICAL MOTION BUT WITH STILL A
RESIDUALLY DRY AND STRONGLY CAPPED REGIME OVER OUR REGION. SURFACE
HIGH PRESSURE WILL CONSEQUENTLY BECOME UNSEASONABLY STRONG - INTO
THE 1040-1045 MB RANGE AS IT BUILDS FROM THE OH VALLEY TO NEW
ENGLAND. UNSEASONABLY COOL NORTHEASTERLY FLOW...WITH TEMPERATURES 10
TO 20 DEGREES BELOW AVERAGE...WILL RESULT OVER CENTRAL NC. INITIALLY
CLEAR SKIES WED WILL BECOME PARTLY CLOUDY...TO PERHAPS MOSTLY SO IN
THE COASTAL PLAIN...BY THU AFTERNOON...AS MOISTURE FLAT
STRATOCUMULUS IS ADVECTED INLAND BENEATH THE CAP.
PROJECTED LOW LEVEL THICKNESS VALUES IN THE 1300-1310 METER RANGE AT
12Z THU AND CLEAR SKIES WOULD SUPPORT SUB-FREEZING TEMPERATURES THU
MORNING...BUT CONFIDENCE IS LOW REGARDING THE DEGREE OF CALM GIVEN A
PROJECTED 4-6 MB RISE IN MSL PRESSURE WITH THE STRENGTHENING HIGH
WED NIGHT. WILL ADJUST LOWS TO REFLECT MOSTLY LOWER TO MIDDLE
30S...COOLEST WEST...BUT THESE MAY NEED FURTHER DOWNWARD ADJUSTMENT
(OR AT LEAST OPEN THE RANGE) TO INCLUDE SOME UPPER 20S (AROUND
RECORD LOWS) IF IT INDEED APPEARS ANY PERIOD OF APPRECIABLE CALM
WILL BE ATTAINED. SIMILARLY COOL IN THE MIDDLE 50S WED...WHICH MAY
THREATEN THE RECORD LOW MAX OF 56 DEGREES AT KFAY FOR THE DATE. SEE
CLIMATE SECTION BELOW. SLOW MODERATION TO AROUND 60 AND 40 DEGREES
FOR HIGHS AND LOWS...RESPECTIVELY...THU AND THU NIGHT. -MWS
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 300 AM MONDAY...
THOUGH MODEL SOLUTION SPREAD REMAINS ABOVE AVERAGE DURING THE LONG
TERM...THE EMERGING SIGNAL FROM THE MAJORITY OF BOTH THE ENSEMBLE
AND SOLUTIONS OS FOR A DOMINANT NORTHERN STREAM ACROSS THE NORTHERN
THIRD OF THE US...ONE THAT WILL INCLUDE AT LEAST ONE PRIMARY
SHORTWAVE TROUGH AND ACCOMPANYING SURFACE CYCLONE FORECAST TO CROSS
THE UPPER MIDWEST AND LOWER GREAT LAKES FRI-SAT - A STORM TRACK THAT
WOULD RESULT IN A MOSTLY DRY COLD FRONTAL PASSAGE SAT-SAT NIGHT AS
DEPICTED BY AT LEAST THE LAST SEVERAL RUNS OF THE GFS. ON THE OTHER
HAND...THE LAST COUPLE OF RUNS OF THE OPERATIONAL ECMWF...WHICH HAVE
MINIMAL SUPPORT FROM THE EC ENSEMBLE MEAN...SUGGEST MORE IN THE WAY
OF SOUTHERN STREAM TROUGHING/INTERACTION THAT WOULD RESULT IN SOME
DEGREE OF COASTAL CYCLOGENESIS AND A WETTER PATTERN FOR AT LEAST THE
EASTERN HALF OF NC DURING THE SAME TIME FRAME. IN EITHER
SCENARIO...THE BEST CHANCES OF RAIN WOULD BE LATE FRI NIGHT-SAT
EVENING...SO MENTIONABLE POP WILL BE CONFINED TO THAT TIME UNTIL A
CLEARER PICTURE EMERGES.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 155 PM MONDAY...
ASIDE FROM A THREAT OF BKN MVFR CIGS NEAR INT/GSO EARLY IN THE TAF
PERIOD FROM 18Z-20Z TODAY... A PERIOD OF CONTINUED PREVAILING VFR
CONDITIONS EXPECTED THIS AFTERNOON INTO EARLY EVENING (THROUGH
AROUND 02Z OR 03Z)... WITH WINDS FROM THE SOUTH AT 8-15 KTS
SPORADICALLY GUSTING TO 15-20 KTS... AND VFR CIGS. PATCHY SHOWERS
MAY OCCUR PRIMARILY AT FAY... BUT ARE UNLIKELY TO LAST ANY MORE THAN
15 MIN AT ANY ONE TIME. AVIATION CONDITIONS ARE EXPECTED TO
DETERIORATE THIS EVENING... AROUND 02Z OR 03Z... WITH CIGS DROPPING
TO MVFR THEN FAIRLY QUICKLY TO IFR IN THE 04Z-06Z TIME FRAME... WITH
CONTINUED STOUT WINDS FROM THE SOUTH AND SSW (FROM 180-210 DEGREES)
STRENGTHENING TO AROUND 14-17 KTS GUSTING TO 20-25 KTS OVERNIGHT.
EXPECT ON-AND-OFF MAINLY MVFR-VSBY-PRODUCING SHOWERS FROM THIS 04Z-
06Z TIME FRAME THROUGH AROUND 11Z-13Z. WINDS WILL REMAIN BLUSTERY
FROM THE SSW THROUGH THE END OF THE TAF VALID PERIOD... POTENTIALLY
INDUCING MECHANICAL TURBULENCE... BUT A LULL IN SHOWERS IS THEN
EXPECTED FROM THIS 11Z-13Z WINDOW LASTING A FEW HOURS. CIGS MAY RISE
A BIT TO MVFR DURING THIS RELATIVE LULL IN PRECIP. HOWEVER... AS A
STRONG COLD FRONT APPROACHES FROM THE WEST... INT/GSO MAY SEE
WIDESPREAD SHOWERS/STORMS MOVING IN TOWARD THE END OF THE TAF VALID
PERIOD (AFTER 16Z).
LOOKING BEYOND 18Z TUE: WIDESPREAD SHOWERS AND STORMS GENERATING IFR
CONDITIONS WILL SPREAD WEST TO EAST ACROSS CENTRAL NC FROM 18Z
THROUGH 06Z... AS A STRONG COLD FRONT CROSSES THE STATE. STRONG
WINDS FROM THE SSW AND SW WILL SHIFT ABRUPTLY TO BE FROM THE NW TUE
AFTERNOON. HIGH CONFIDENCE IN CLEARING SKIES AND VFR CONDITIONS POST-
FRONT AFTER MIDNIGHT TUE NIGHT LASTING THROUGH THU EVENING. THERE IS
A CHANCE OF SHALLOW LOW STRATUS LATE THU NIGHT/EARLY FRI MORNING...
THEN A BETTER CHANCE OF THICKER LOW STRATUS FRI NIGHT THROUGH NOON
SAT AHEAD OF THE NEXT STORM SYSTEM MOVING IN FROM THE SOUTH. -GIH
&&
.CLIMATE...
THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING...
AND THE RECORD LOW MAXIMUM TEMPERATURES FOR THU:
WED 04/16 THU 04/17
LOW/YEAR LOW MAX/YEAR LOW/YEAR
FAY: 28/1943 56/1950 31/1953
GSO: 25/1943 48/1929 29/1953
RDU: 28/1950 46/1890 29/1962
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...DJF/SR/VINCENT
SHORT TERM...VINCENT
LONG TERM...MWS
AVIATION...HARTFIELD
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
123 PM EDT MON APR 14 2014
.SYNOPSIS...
HIGH PRESSURE WILL MAINTAIN CONTROL OF THE WEATHER INTO TODAY. A COLD
FRONT WILL MOVE ACROSS THE AREA TUESDAY...WITH INCREASING CHANCES
FOR SHOWERS AND POSSIBLY THUNDERSTORMS LATE MONDAY INTO TUESDAY.
HIGH PRESSURE WILL MOVE INTO THE AREA WEDNESDAY AND CONTROL AREA
WEATHER INTO FRIDAY BEFORE CONDITIONS DETERIORATE IN ADVANCE OF A
COLD FRONT THAT WILL MOVE THROUGH THE AREA SATURDAY NIGHT OR EARLY
SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1200 PM MONDAY...CURRENT RADAR IMAGERY SHOWS LIGHT SHOWERS
MOVING ONSHORE AROUND THE WESTERN PERIPHERY OF HIGH PRESSURE WELL
OFF THE ATLANTIC COAST. HAVE TRIMMED BACK POPS FOR OUR FAR WESTERN
ZONES THIS AFTERNOON BASED ON RADAR TRENDS AND DRY MID-LEVEL AIR
DEPICTED IN FCST SOUNDINGS. STILL EXPECT PCPN COVERAGE TO GRADUALLY
INCREASE LATER TODAY INTO THIS EVENING AS DEPICTED BY HRRR AND OTHER
HI RES MODELS. THE REST OF THE FORECAST STILL APPEARS ON TRACK ATTM.
PREVIOUS DISCUSSION AS FOLLOWS...
AS OF 1000 AM MONDAY...ANOTHER WARM DAY EXPECTED AS HIGH PRESSURE
ONLY SLOWLY LOSES ITS GRIP ACROSS THE CAROLINAS...BUT MUCH MORE
CLOUD COVER TODAY WILL KEEP TEMPS SEVERAL DEGREES COOLER THAN
PREVIOUS DAYS. THIS CLOUD COVER IS DUE TO A COMBINATION OF INCREASED
LOW LEVEL MOISTURE DUE TO ADVECTION OFF THE ATLANTIC...AND HIGH/MID
CLOUDINESS AHEAD OF A STRONG COLD FRONT APPROACHING FROM THE WEST.
THIS FRONT IS TRAILING FROM A CYCLONE MOVING UP THROUGH THE GREAT
LAKES...AND ALTHOUGH ITS DIRECT IMPACTS WILL HOLD OFF UNTIL AFTER
THIS PERIOD...CLOUDS AND SHOWERS WILL SLOWLY INCREASE IN COVERAGE
TODAY.
KLTX RADAR THIS MORNING HAS SHOWN A FEW SHOWERS TRYING TO MOVE
ONSHORE FROM THE ATLANTIC ON S/SE WINDS...BUT MOST OF THESE ARE
EVAPORATING AS THEY MOVE ACROSS THE COOLER SHELF WATERS...BEFORE
COMING ONSHORE. EXPECT THIS TREND TO CONTINUE THROUGH THE AFTN...BUT
COVERAGE AND INTENSITY OF THESE SHOWERS WILL LIKELY INCREASE AS
MOISTURE AND INSTABILITY BECOME MORE SIGNIFICANT...AND AN ISOLATED
RUMBLE OF THUNDER IS POSSIBLE. MOST OF THE HIGH RES
MODELS...HRRR/ARW/WRF...SHOW A SIMILAR PATTERN OF SHOWERS MOVING
ONSHORE BEFORE ROTATING NORTH AROUND THE HIGH PRESSURE...AND DUE TO
THIS AGREEMENT HAVE SHOWN POP GRIDS WHICH MATCH THIS IDEA. AT THE
SAME TIME...PRECIP WILL SLOWLY INCREASE FROM THE WEST AS THE COLD
FRONT APPROACHES. MID-LEVEL DRYNESS WILL BE TOUGH TO OVERCOME...BUT
BY TONIGHT FORECAST PROFILES SATURATE AND RAIN SHOWERS ARE EXPECTED
TO BECOME NUMEROUS ACROSS THE AREA. TOTAL QPF WILL BE LIGHT THROUGH
THE DAY...AS THE HEAVIEST RAIN HOLDS OFF UNTIL AFTER THE NEAR TERM
PERIOD.
TEMPS TODAY WILL RISE INTO THE MID/UPR 70S...HIGHEST INLAND. LOWS
TONIGHT WILL BE TEMPERED BY CONTINUING SOUTHERLY WINDS AND
INCREASING RAIN SHOWERS/CLOUD COVER...SO EXPECT A RATHER MINIMAL
DIURNAL RANGE WITH MINS IN THE UPPER 60S AT THE COAST...MID 60S
INLAND.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 330 AM MONDAY...MID TO UPPER TROUGH EXTENDING DOWN FROM THE
GREAT LAKES TO THE GULF COAST WILL PUSH A COLD FRONT EAST THROUGH
THE CAROLINAS ON TUESDAY. INCREASINGLY WARM AND HUMID AIR MASS AHEAD
OF THE FRONT WITH DEWPOINT TEMPS INTO THE MID 60S...WILL SET THE
STAGE FOR INCREASED SHWR/TSTM ACTIVITY. LLJ UP TO 45 KTS COMBINED
WITH MID TO UPPER LEVEL SUPPORT INCLUDING A STRONG JET WILL AID IN
CONVECTIVE DEVELOPMENT. SPC CONTINUES TO HOLD US IN SLIGHT RISK WITH
MAIN THREAT AS DAMAGING WIND AND POTENTIAL FOR A TORNADO IN SOME
LINE SEGMENTS AND EMBEDDED SUPERCELLS TUES AFTN. THE CLOUDS MAY COME
INTO PLAY AS A LIMITING FACTOR WORKING AGAINST THE CONTINUED WAA
THROUGH TUES...BUT TEMPS WILL ALREADY BE WELL INTO THE 60S TO START
THE DAY AND SHOULD MAKE IT WELL INTO THE 70S IN MOST PLACES. TEMPS
SHOULD MODERATE WITH PLENTY OF MID TO HIGH CLOUDS OVER THE AREA
AHEAD OF THE ACTUAL FRONT. BEST LIFT WILL COME AS FRONT MOVES
THROUGH FROM WEST TO EAST THROUGH LATE AFTN INTO THE EVENING.
A TOTAL CHANGE IN AIR MASS WILL COME AS HIGH PRESSURE BUILDS IN
BEHIND FRONT THROUGH WED MORNING. PLENTY OF DRY AIR AND SUBSIDENCE
WILL BE IN PLACE WITH CLEARING SKIES THROUGH DAYBREAK WED. PCP
WATER VALUES UP AROUND 1.8 INCHES AHEAD OF FRONT LATE TUES WILL
DROP TO AS LOW AS A QUARTER OF AN INCH BY WED MORNING. 850 TEMPS
WILL PLUMMET FROM CLOSE TO 13C DOWN NEAR 4C BY WED MORNING. THIS
STRONG CAA WILL BRING TEMPS DOWN ABOUT 20 DEGREES F FROM TUES TO
WED. TEMPS BY WED MORNING WILL BE DOWN IN THE 30S OVER SOME PLACES
INLAND. DEWPOINT TEMPS WILL DROP FROM THE MID 60S AHEAD OF THE
FRONT DOWN TO MID 20S BY TUES AFTN. OVERALL EXPECT COOL NORTHERLY
WINDS TO BE OFFSET BY PLENTY OF APRIL SUNSHINE TO PRODUCE TEMPS
CLOSE TO 60. A PINCHED GRADIENT FLOW WILL KEEP N-NE FLOW
REINFORCING THE COOL AIR THROUGH THURS NIGHT. TEMPS SHOULD DROP
ONCE AGAIN INTO THE 30S MANY PLACES INLAND.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 330 AM MONDAY...COOL AND DRY HIGH PRESSURE WILL BE IN PLACE
AS WEDGE LIKE PATTERN DEVELOPS THURS INTO FRI WITH TROUGH OFF
SHORE. THE GREATER ON SHORE COMPONENT TO THE FLOW WILL ALLOW
MOISTURE TO INCREASE SLIGHTLY THROUGH THURS AND FURTHER INTO
FRIDAY. PCP WATER VALUES REMAIN DOWN BELOW A HALF INCH THROUGH
THURS BUT AS LOW PRESSURE DEVELOPS AND RISES UP FROM THE GULF
COAST THROUGH FRI...THE SHALLOW COOL AND DRY AIR WILL BE OVERRUN
WITH SOUTHERLY WINDS THROUGH THE LOW LEVELS. THIS WILL PROVIDE
INCREASE ISENTROPIC LIFT THROUGH THE LATE THURS INTO FRI WITH
LOW CLOUDS AND POSSIBILITY OF PCP. THE MOISTURE WILL REMAIN
SHALLOW...BASICALLY BELOW 5K FT. AT THE SAME TIME A NORTHERN
STREAM SYSTEM MOVES EAST DRAGGING A COLD FRONT TOWARD THE
CAROLINAS. THIS SYSTEM MAY KEEP THE BEST MOISTURE AND LIFT OFF
SHORE THROUGH FRI LEAVING A WEAKENING COLD FRONT MOVING THROUGH ON
SATURDAY. KEPT POPS UP ON FRI ALTHOUGH NOT CONFIDENT THAT ENOUGH
MOISTURE AND LIFT WILL REACH THIS FAR NORTH FROM GULF LOW BEFORE
MOVING OFF SHORE. MAY END UP BEING MUCH MORE IN THE WAY OF CLOUDS
THURS INTO FRI THAN PCP. TEMPS WILL REMAIN BELOW NORMAL IN CAA
INITIALLY AND THEN CLOUDS WILL KEEP TEMPS LOWER.
HIGH PRESSURE WILL BUILD IN BEHIND FRONT THROUGH SATURDAY INTO
SUNDAY. ANOTHER COLD FRONT MAY MOVE EARLY NEXT WEEK WITH INCREASED
CLOUDS AND CHC OF PCP BY SUN NIGHT. TEMPS WILL REACH BACK UP
TOWARD NORMAL THROUGH THE WEEKEND.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 18Z...A STABLE LAYER AROUND 6500 FT HAS KEPT THE ATMOSPHERE A
BIT CAPPED...BUT THAT STABLE LAYER SHOULD DISSIPATE THIS EVENING
WITH MORE WIDESPREAD CONVECTION EXPECTED TO BREAK OUT AFTER
MIDNIGHT. CEILINGS WILL LOWER WITH THE COMMENCEMENT OF
PRECIP...POSSIBLY IFR CONDITIONS INLAND. WINDS WILL STAY ABOVE 7-8
KTS OVERNIGHT...IN FACT THEY WILL INCREASE TOWARD MORNING AS THE
GRADIENT TIGHTENS AHEAD OF THE FRONT.
TUESDAY...CONVECTION WILL BE IN AND OUT WITH DECENT COVERAGE. MODELS
INDICATE WE WILL GET ENOUGH SOLAR INSOLATION AND WARM AIR ADVECTION
TO SUPPORT POSSIBLE STRONG STORMS AFTER MIDDAY...STARTING FROM THE
SOUTHWEST. CAPE COULD APPROACH 1000 J/KG WITH 55 KTS AT 2500 FEET.
THE MARINE LAYER MAY SPARE THE COAST FROM STRONG STORMS IF THEY WAIT
TO ARRIVE BY LATE AFTERNOON OR EVENING.
EXTENDED OUTLOOK...BECOMING VFR TUESDAY NIGHT...CONTINUING THROUGH
THURSDAY. POSSIBLE FOG/STRATUS FRIDAY AND SATURDAY...LOW CONFIDENCE.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM MONDAY...HIGH PRESSURE CENTERED WELL OFFSHORE
CONTINUES TO RIDGE BACK TOWARDS THE SOUTHEAST...BUT IS SLOWLY LOSING
ITS GRIP OVER THE AREA. THIS IS DRIVING S/SE WINDS OF 10-15 KTS AT
THE LOCAL BUOYS...WHICH WILL GRADUALLY VEER MORE TO THE SOUTH AND
INCREASE TO 15-20 KTS TONIGHT. LOCAL SWAN GUIDANCE IS ABOUT 1 FT TOO
HIGH WITH CURRENT SEAS...SO HAVE BLENDED DOWN WITH WNAWAVE TO MORE
ACCURATELY REPRESENT ONGOING CONDITIONS...AND SHOW A SLOWER RISE IN
WAVE HEIGHTS TONIGHT. STILL EXPECT SEAS TO BUILD TO 4-6 FT
TONIGHT...AND A SMALL CRAFT ADVISORY REMAINS IN EFFECT...BEGINNING
AT 2 AM TUESDAY.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 330 AM MONDAY...SMALL CRAFT CONDITIONS WILL PERSIST THROUGH
MUCH OF THE PERIOD IN STRONG SOUTHERLY WINDS AHEAD OF A COLD FRONT
AND NORTHERLY SURGE BEHIND COLD FRONT TUES NIGHT THROUGH WED
NIGHT. MAY REACH GALE CRITERIA TUES NIGHT IN COLD SURGE AS HIGH
PRESSURE BUILDS IN BEHIND COLD FRONT.
WINDS WILL INCREASE UP TO 20 TO 25 KT TUESDAY BEFORE RAPIDLY
SHIFTING TO THE NORTH AND INCREASING TO 25 TO 30 KT LATE TUESDAY
NIGHT. SEAS WILL CONTINUE TO BUILD THROUGH TUES FROM 5 TO 7 FT UP
TO 6 TO 8 FT TUES EVENING. AFTER THE COLD FRONT MOVES THROUGH TUESDAY
EVENING A STRONG NORTHERLY FLOW UP TO 30 KTS WILL KEEP SEAS UP
POSSIBLY TO 9 FT IN OUTER WATERS OVERNIGHT TUES INTO EARLY WED.
GRADIENT WILL REMAIN TIGHT THROUGH WED AS NORTHERLY WINDS VEER
SLIGHTLY TO THE NE AS HIGH PRESSURE RIDGES DOWN THROUGH THE
CAROLINAS FROM THE NORTHEAST.
LONG TERM /THURSDAY THROUGH FRIDAY/...
AS OF 330 AM MONDAY...HIGH PRESSURE WILL CONTINUE TO RIDGE DOWN
THROUGH THE CAROLINAS WHILE A WAVE OF LOW PRESSURE DEVELOPS OFF
SHORE ALONG LINGERING COLD FRONT. STRONG NORTHERLY SURGE OF COLD
AIR AND TIGHTENED GRADIENT FLOW WILL MAINTAIN N-NE WINDS CLOSER TO
20 KTS INITIALLY ACROSS THE WATERS THROUGH THURSDAY. WINDS WILL
LIGHTEN AND VEER SLIGHTLY LATE THURS REMAINING CLOSER TO 15 KTS
THROUGH FRI. SEAS SHOULD DROP DOWN BUT REMAIN 4 TO 6 FT THROUGH
THURS NIGHT INTO FRI.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 AM TUESDAY TO 6 PM EDT
WEDNESDAY FOR AMZ250-252-254-256.
&&
$$
SYNOPSIS...SHK
NEAR TERM...JDW/BJR
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...43
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1214 PM EDT MON APR 14 2014
.SYNOPSIS...
HIGH PRESSURE WILL MAINTAIN CONTROL OF THE WEATHER INTO TODAY. A COLD
FRONT WILL MOVE ACROSS THE AREA TUESDAY...WITH INCREASING CHANCES
FOR SHOWERS AND POSSIBLY THUNDERSTORMS LATE MONDAY INTO TUESDAY.
HIGH PRESSURE WILL MOVE INTO THE AREA WEDNESDAY AND CONTROL AREA
WEATHER INTO FRIDAY BEFORE CONDITIONS DETERIORATE IN ADVANCE OF A
COLD FRONT THAT WILL MOVE THROUGH THE AREA SATURDAY NIGHT OR EARLY
SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1200 PM MONDAY...CURRENT RADAR IMAGERY SHOWS LIGHT SHOWERS
MOVING ONSHORE AROUND THE WESTERN PERIPHERY OF HIGH PRESSURE WELL
OFF THE ATLANTIC COAST. HAVE TRIMMED BACK POPS FOR OUR FAR WESTERN
ZONES THIS AFTERNOON BASED ON RADAR TRENDS AND DRY MID-LEVEL AIR
DEPICTED IN FCST SOUNDINGS. STILL EXPECT PCPN COVERAGE TO GRADUALLY
INCREASE LATER TODAY INTO THIS EVENING AS DEPICTED BY HRRR AND OTHER
HI RES MODELS. THE REST OF THE FORECAST STILL APPEARS ON TRACK ATTM.
PREVIOUS DISCUSSION AS FOLLOWS...
AS OF 1000 AM MONDAY...ANOTHER WARM DAY EXPECTED AS HIGH PRESSURE
ONLY SLOWLY LOSES ITS GRIP ACROSS THE CAROLINAS...BUT MUCH MORE
CLOUD COVER TODAY WILL KEEP TEMPS SEVERAL DEGREES COOLER THAN
PREVIOUS DAYS. THIS CLOUD COVER IS DUE TO A COMBINATION OF INCREASED
LOW LEVEL MOISTURE DUE TO ADVECTION OFF THE ATLANTIC...AND HIGH/MID
CLOUDINESS AHEAD OF A STRONG COLD FRONT APPROACHING FROM THE WEST.
THIS FRONT IS TRAILING FROM A CYCLONE MOVING UP THROUGH THE GREAT
LAKES...AND ALTHOUGH ITS DIRECT IMPACTS WILL HOLD OFF UNTIL AFTER
THIS PERIOD...CLOUDS AND SHOWERS WILL SLOWLY INCREASE IN COVERAGE
TODAY.
KLTX RADAR THIS MORNING HAS SHOWN A FEW SHOWERS TRYING TO MOVE
ONSHORE FROM THE ATLANTIC ON S/SE WINDS...BUT MOST OF THESE ARE
EVAPORATING AS THEY MOVE ACROSS THE COOLER SHELF WATERS...BEFORE
COMING ONSHORE. EXPECT THIS TREND TO CONTINUE THROUGH THE AFTN...BUT
COVERAGE AND INTENSITY OF THESE SHOWERS WILL LIKELY INCREASE AS
MOISTURE AND INSTABILITY BECOME MORE SIGNIFICANT...AND AN ISOLATED
RUMBLE OF THUNDER IS POSSIBLE. MOST OF THE HIGH RES
MODELS...HRRR/ARW/WRF...SHOW A SIMILAR PATTERN OF SHOWERS MOVING
ONSHORE BEFORE ROTATING NORTH AROUND THE HIGH PRESSURE...AND DUE TO
THIS AGREEMENT HAVE SHOWN POP GRIDS WHICH MATCH THIS IDEA. AT THE
SAME TIME...PRECIP WILL SLOWLY INCREASE FROM THE WEST AS THE COLD
FRONT APPROACHES. MID-LEVEL DRYNESS WILL BE TOUGH TO OVERCOME...BUT
BY TONIGHT FORECAST PROFILES SATURATE AND RAIN SHOWERS ARE EXPECTED
TO BECOME NUMEROUS ACROSS THE AREA. TOTAL QPF WILL BE LIGHT THROUGH
THE DAY...AS THE HEAVIEST RAIN HOLDS OFF UNTIL AFTER THE NEAR TERM
PERIOD.
TEMPS TODAY WILL RISE INTO THE MID/UPR 70S...HIGHEST INLAND. LOWS
TONIGHT WILL BE TEMPERED BY CONTINUING SOUTHERLY WINDS AND
INCREASING RAIN SHOWERS/CLOUD COVER...SO EXPECT A RATHER MINIMAL
DIURNAL RANGE WITH MINS IN THE UPPER 60S AT THE COAST...MID 60S
INLAND.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 330 AM MONDAY...MID TO UPPER TROUGH EXTENDING DOWN FROM THE
GREAT LAKES TO THE GULF COAST WILL PUSH A COLD FRONT EAST THROUGH
THE CAROLINAS ON TUESDAY. INCREASINGLY WARM AND HUMID AIR MASS AHEAD
OF THE FRONT WITH DEWPOINT TEMPS INTO THE MID 60S...WILL SET THE
STAGE FOR INCREASED SHWR/TSTM ACTIVITY. LLJ UP TO 45 KTS COMBINED
WITH MID TO UPPER LEVEL SUPPORT INCLUDING A STRONG JET WILL AID IN
CONVECTIVE DEVELOPMENT. SPC CONTINUES TO HOLD US IN SLIGHT RISK WITH
MAIN THREAT AS DAMAGING WIND AND POTENTIAL FOR A TORNADO IN SOME
LINE SEGMENTS AND EMBEDDED SUPERCELLS TUES AFTN. THE CLOUDS MAY COME
INTO PLAY AS A LIMITING FACTOR WORKING AGAINST THE CONTINUED WAA
THROUGH TUES...BUT TEMPS WILL ALREADY BE WELL INTO THE 60S TO START
THE DAY AND SHOULD MAKE IT WELL INTO THE 70S IN MOST PLACES. TEMPS
SHOULD MODERATE WITH PLENTY OF MID TO HIGH CLOUDS OVER THE AREA
AHEAD OF THE ACTUAL FRONT. BEST LIFT WILL COME AS FRONT MOVES
THROUGH FROM WEST TO EAST THROUGH LATE AFTN INTO THE EVENING.
A TOTAL CHANGE IN AIR MASS WILL COME AS HIGH PRESSURE BUILDS IN
BEHIND FRONT THROUGH WED MORNING. PLENTY OF DRY AIR AND SUBSIDENCE
WILL BE IN PLACE WITH CLEARING SKIES THROUGH DAYBREAK WED. PCP
WATER VALUES UP AROUND 1.8 INCHES AHEAD OF FRONT LATE TUES WILL
DROP TO AS LOW AS A QUARTER OF AN INCH BY WED MORNING. 850 TEMPS
WILL PLUMMET FROM CLOSE TO 13C DOWN NEAR 4C BY WED MORNING. THIS
STRONG CAA WILL BRING TEMPS DOWN ABOUT 20 DEGREES F FROM TUES TO
WED. TEMPS BY WED MORNING WILL BE DOWN IN THE 30S OVER SOME PLACES
INLAND. DEWPOINT TEMPS WILL DROP FROM THE MID 60S AHEAD OF THE
FRONT DOWN TO MID 20S BY TUES AFTN. OVERALL EXPECT COOL NORTHERLY
WINDS TO BE OFFSET BY PLENTY OF APRIL SUNSHINE TO PRODUCE TEMPS
CLOSE TO 60. A PINCHED GRADIENT FLOW WILL KEEP N-NE FLOW
REINFORCING THE COOL AIR THROUGH THURS NIGHT. TEMPS SHOULD DROP
ONCE AGAIN INTO THE 30S MANY PLACES INLAND.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 330 AM MONDAY...COOL AND DRY HIGH PRESSURE WILL BE IN PLACE
AS WEDGE LIKE PATTERN DEVELOPS THURS INTO FRI WITH TROUGH OFF
SHORE. THE GREATER ON SHORE COMPONENT TO THE FLOW WILL ALLOW
MOISTURE TO INCREASE SLIGHTLY THROUGH THURS AND FURTHER INTO
FRIDAY. PCP WATER VALUES REMAIN DOWN BELOW A HALF INCH THROUGH
THURS BUT AS LOW PRESSURE DEVELOPS AND RISES UP FROM THE GULF
COAST THROUGH FRI...THE SHALLOW COOL AND DRY AIR WILL BE OVERRUN
WITH SOUTHERLY WINDS THROUGH THE LOW LEVELS. THIS WILL PROVIDE
INCREASE ISENTROPIC LIFT THROUGH THE LATE THURS INTO FRI WITH
LOW CLOUDS AND POSSIBILITY OF PCP. THE MOISTURE WILL REMAIN
SHALLOW...BASICALLY BELOW 5K FT. AT THE SAME TIME A NORTHERN
STREAM SYSTEM MOVES EAST DRAGGING A COLD FRONT TOWARD THE
CAROLINAS. THIS SYSTEM MAY KEEP THE BEST MOISTURE AND LIFT OFF
SHORE THROUGH FRI LEAVING A WEAKENING COLD FRONT MOVING THROUGH ON
SATURDAY. KEPT POPS UP ON FRI ALTHOUGH NOT CONFIDENT THAT ENOUGH
MOISTURE AND LIFT WILL REACH THIS FAR NORTH FROM GULF LOW BEFORE
MOVING OFF SHORE. MAY END UP BEING MUCH MORE IN THE WAY OF CLOUDS
THURS INTO FRI THAN PCP. TEMPS WILL REMAIN BELOW NORMAL IN CAA
INITIALLY AND THEN CLOUDS WILL KEEP TEMPS LOWER.
HIGH PRESSURE WILL BUILD IN BEHIND FRONT THROUGH SATURDAY INTO
SUNDAY. ANOTHER COLD FRONT MAY MOVE EARLY NEXT WEEK WITH INCREASED
CLOUDS AND CHC OF PCP BY SUN NIGHT. TEMPS WILL REACH BACK UP
TOWARD NORMAL THROUGH THE WEEKEND.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AS OF 12Z...DENSE CIRRUS AND WINDS AROUND 5 KTS HAVE KEPT FOG AT BAY
THIS MORNING. INCREASING CLOUDS TODAY AS THE COLD FRONT APPROACHES.
AHEAD OF THE FRONT...LOOK FOR RISING DEWPOINTS AND AN INCREASING
SOUTH WIND. SOME CONVERGENT BOUNDARIES AS WELL AS THE RESULTANT
COULD KICK OFF LIGHT SHOWERS THIS AFTERNOON...FAIRLY SPARSE COVERAGE
WITH A VCSH MENTION. TONIGHT...CEILINGS WILL LOWER AND PRECIPITATION
WILL BECOME MORE WIDESPREAD TOWARD MORNING. THE PRESSURE GRADIENT
WILL CONTINUE TO TIGHTEN...WITH GUSTY WINDS POSSIBLE AFTER MIDNIGHT.
EXTENDED OUTLOOK...CHANCE OF SHOWERS AND MVFR CONDITIONS INTO
TUESDAY WITH SHOWERS AND/OR THUNDERSTORMS ALONG A PASSING COLD
FRONT. VFR WEDNESDAY AND THURSDAY. POSSIBLE FOG/STRATUS THURSDAY
NIGHT INTO FRIDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM MONDAY...HIGH PRESSURE CENTERED WELL OFFSHORE
CONTINUES TO RIDGE BACK TOWARDS THE SOUTHEAST...BUT IS SLOWLY LOSING
ITS GRIP OVER THE AREA. THIS IS DRIVING S/SE WINDS OF 10-15 KTS AT
THE LOCAL BUOYS...WHICH WILL GRADUALLY VEER MORE TO THE SOUTH AND
INCREASE TO 15-20 KTS TONIGHT. LOCAL SWAN GUIDANCE IS ABOUT 1 FT TOO
HIGH WITH CURRENT SEAS...SO HAVE BLENDED DOWN WITH WNAWAVE TO MORE
ACCURATELY REPRESENT ONGOING CONDITIONS...AND SHOW A SLOWER RISE IN
WAVE HEIGHTS TONIGHT. STILL EXPECT SEAS TO BUILD TO 4-6 FT
TONIGHT...AND A SMALL CRAFT ADVISORY REMAINS IN EFFECT...BEGINNING
AT 2 AM TUESDAY.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 330 AM MONDAY...SMALL CRAFT CONDITIONS WILL PERSIST THROUGH
MUCH OF THE PERIOD IN STRONG SOUTHERLY WINDS AHEAD OF A COLD FRONT
AND NORTHERLY SURGE BEHIND COLD FRONT TUES NIGHT THROUGH WED
NIGHT. MAY REACH GALE CRITERIA TUES NIGHT IN COLD SURGE AS HIGH
PRESSURE BUILDS IN BEHIND COLD FRONT.
WINDS WILL INCREASE UP TO 20 TO 25 KT TUESDAY BEFORE RAPIDLY
SHIFTING TO THE NORTH AND INCREASING TO 25 TO 30 KT LATE TUESDAY
NIGHT. SEAS WILL CONTINUE TO BUILD THROUGH TUES FROM 5 TO 7 FT UP
TO 6 TO 8 FT TUES EVENING. AFTER THE COLD FRONT MOVES THROUGH TUESDAY
EVENING A STRONG NORTHERLY FLOW UP TO 30 KTS WILL KEEP SEAS UP
POSSIBLY TO 9 FT IN OUTER WATERS OVERNIGHT TUES INTO EARLY WED.
GRADIENT WILL REMAIN TIGHT THROUGH WED AS NORTHERLY WINDS VEER
SLIGHTLY TO THE NE AS HIGH PRESSURE RIDGES DOWN THROUGH THE
CAROLINAS FROM THE NORTHEAST.
LONG TERM /THURSDAY THROUGH FRIDAY/...
AS OF 330 AM MONDAY...HIGH PRESSURE WILL CONTINUE TO RIDGE DOWN
THROUGH THE CAROLINAS WHILE A WAVE OF LOW PRESSURE DEVELOPS OFF
SHORE ALONG LINGERING COLD FRONT. STRONG NORTHERLY SURGE OF COLD
AIR AND TIGHTENED GRADIENT FLOW WILL MAINTAIN N-NE WINDS CLOSER TO
20 KTS INITIALLY ACROSS THE WATERS THROUGH THURSDAY. WINDS WILL
LIGHTEN AND VEER SLIGHTLY LATE THURS REMAINING CLOSER TO 15 KTS
THROUGH FRI. SEAS SHOULD DROP DOWN BUT REMAIN 4 TO 6 FT THROUGH
THURS NIGHT INTO FRI.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 AM TUESDAY TO 6 PM EDT
WEDNESDAY FOR AMZ250-252-254-256.
&&
$$
SYNOPSIS...SHK
NEAR TERM...JDW/BJR
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...43
AREA FORECAST DISCUSSION
NWS NORMAN OK
1241 PM CDT MON APR 14 2014
.AVIATION...
VFR CEILINGS WILL SCATTERED ACROSS CENTRAL OKLAHOMA THIS AFTERNOON
WITH GUSTY NORTH WINDS PREVAILING. SKIES WILL BE MAINLY CLEAR
TONIGHT WITH LIGHT NORTH WINDS BECOMING SOUTHWEST IN WESTERN
OKLAHOMA EARLY TUESDAY.
&&
.PREV DISCUSSION... /ISSUED 1011 AM CDT MON APR 14 2014/
UPDATE...
UPDATE TO PRECIP FORECAST...
DISCUSSION...
LIGHT SNOW CONTINUES TO FALL ACROSS PORTIONS OF NRN AND CENTRAL
OK... WITH AN AREA OF SNOW SLOWLY MOVING E/SE ACROSS PORTIONS OF
THE OKC METRO. IMPACTS ARE EXPECTED TO BE LIMITED... OKDOT
TRAFFIC CAMS AND REPORTS VIA SOCIAL MEDIA SHOW LIGHT SNOW
FALLING... WITH VISIBILITIES DROPPING NEAR 1 TO 1 1/2 MILES.
UPDATED FORECAST TO REFLECT CURRENT PATH OF SNOW... WITH -RA/SN
MIX POSSIBLE SOUTH OF THE I-44/40 CORRIDOR... CONSIDERING
SFC/BL TEMPS AND RECENT 15Z OBS FROM KCSM AND KHBR... REPORTING
UNKNOWN PRECIP. RAP BUFR SOUNDINGS SHOW BL TEMPS WARMING SLOWLY
THROUGH NOON... WITH DRIER AIR MOVING IN AS THE SFC HIGH ACROSS KS
CONTINUES TO SINK SWRD ACROSS THE SRN PLAINS. EFFECTS OF THIS ARE
ALREADY BEING SEEN ACROSS FAR NWRN OK.
PRECIP... SN... RA/SN WILL CONTINUE AHEAD OF THE SFC HIGH... WHERE
A DECENT REGION OF ISENTROPIC ASCENT RESIDES WITHIN THE 290-295K
LEVEL... SYNONYMOUS WITH THE BEST MOISTURE WITHIN THE 850 TO 700
MB LEVEL. PRECIP WILL CONTINUE TO EXIT TO THE EAST THROUGH NOON...
AS THE H500 TROUGH CONTINUES TO TRACK EWRD AND THE SFC HIGH
SETTLES INTO THE REGION THIS AFTN.
JTK
PREV DISCUSSION... /ISSUED 618 AM CDT MON APR 14 2014/
AVIATION...
MVFR CIGS WILL REMAIN WIDESPREAD THROUGH THE EARLY MORNING. LIGHT
RAIN/SNOW WILL CONTINUE TO MOVE THROUGH NRN HALF OF OK THIS AM.
CIG/VSBYS MAY DROP TO IFR BRIEFLY AT NRN SITES AS THE HEAVIER PRCP
MOVES THROUGH. PRECIP SHOULD END BY LATE MORNING WITH CONDITIONS
IMPROVING TO VFR BY AFTN. STRONG N WINDS WITH FREQUENT GUSTS OVER
30 KTS WILL PERSIST THROUGH THE DAY...BUT SHOULD DIMINISH RAPIDLY
EARLY THIS EVENING.
PREV DISCUSSION... /ISSUED 404 AM CDT MON APR 14 2014/
DISCUSSION...
BAND OF SNOW FROM TX PANHANDLE INTO NW CORNER OF THE FA CONTINUES
TO MOVE STEADILY EWD. SNOWFALL RATES IN THIS BAND SUFFICIENT FOR
SOME LIGHT ACCUMS DESPITE WARM GROUND TEMPS AND AIR TEMPS RIGHT AT
OR SLIGHTLY ABOVE FREEZING. WILL CONTINUE THE WINTER WX ADVY
THROUGH THE EARLY MORNING. BEST CHANCES FOR PRECIP WILL REMAIN
ACROSS THE NRN HALF OF THE FA THIS MORNING AS MID LEVEL TROUGH
MOVES THROUGH. TEMP PROFILES WILL BE COLD ENOUGH FOR SNOW OR
RAIN/SNOW MIX OVER MUCH OF THE NRN HALF OF THE FA THIS MORNING.
PRECIP SHOULD SHUT OFF BY AFTERNOON AS TROUGH TRANSLATES INTO ERN
OK. STRONG NORTH WINDS WILL CONTINUE THROUGH TODAY AND WILL LEAVE
WIND ADVY IN PLACE.
WINDS WILL DROP OFF QUICKLY THIS EVENING AND REMAIN LIGHT
OVERNIGHT AS SURFACE RIDGE SETTLES OVER THE SRN PLAINS. WITH
MOSTLY CLEAR SKIES AND LIGHT WINDS A COLD NIGHT IS IN STORE WITH
BELOW FREEZING TEMPS EXPECTED AREAWIDE AND FREEZE/HARD FREEZE
WARNINGS ARE IN EFFECT. WARMER TEMPS EXPECTED TUESDAY WITH THE
RETURN OF SLY LOW LEVEL FLOW.
ANOTHER S/W TROUGH MOVES IN FROM THE NW AROUND MIDWEEK BRINGING
RAIN CHANCES AND ANOTHER FRONT. DRY WEATHER EXPECTED FRIDAY AND
SATURDAY WITH PRECIP CHANCES RETURNING LATE IN THE WEEKEND AS
SYSTEM APPROACHES FROM THE SOUTHWESTERN U.S.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 29 61 39 66 / 0 0 0 0
HOBART OK 24 63 39 69 / 0 0 0 0
WICHITA FALLS TX 29 63 39 70 / 0 0 0 0
GAGE OK 22 66 41 71 / 0 0 0 0
PONCA CITY OK 24 61 39 67 / 0 0 0 0
DURANT OK 31 60 38 64 / 0 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...HARD FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR OKZ004>025-
027-033>038-044.
FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR OKZ026-028>032-
039>043-045>048-050>052.
TX...HARD FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR TXZ083>089.
FREEZE WARNING FROM 1 AM TO 9 AM CDT TUESDAY FOR TXZ090.
&&
$$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1237 PM CDT MON APR 14 2014
.UPDATE...ADDED AVIATION SECTION FOR 18Z TAF`S.
&&
.AVIATION...BNA/CKV/CSV...DRIER AIR HAS MOVED INTO MIDDLE
TENNESSEE BEHIND THIS MORNING`S SHOWERS. EVEN THOUGH CIGS REMAIN
BELOW 3 KFT ACROSS A LARGE PART OF THE AREA, VERY LITTLE ACTIVE
WEATHER IS OCCURRING AS OF NOW. SURFACE FRONT WILL EDGE INTO
MIDDLE TENNESSEE DURING THE AFTERNOON, WITH A GRADUAL INCREASE IN
RADAR ECHOES AS THE ATMOSPHERE DESTABILIZES SOMEWHAT. MOST OF THE
ACTIVITY WILL HOLD OFF UNTIL AFTER 00Z, WITH IFR CIGS LASTING MOST
OF THE NIGHT. WINDS WILL REMAIN GUSTY AT LEAST THROUGH 18Z
TOMORROW.
&&
.PREV DISCUSSION... /ISSUED 1128 AM CDT MON APR 14 2014/
UPDATE...COLD FRONT HAS NOSED INTO WESTERN KY, ALTHOUGH RADAR
MOSAIC CONTINUES TO SHOW LITTLE ACTIVITY ASSOCIATED WITH THE
FRONT. THE LATEST HRRR DOES SHOW INCREASED DEVELOPMENT ACROSS
MIDDLE TENNESSEE THIS AFTERNOON, ALTHOUGH THE BULK OF THE ACTIVITY
WILL HOLD OFF UNTIL AFTER 00Z. HAVE UPDATED THE PUBLIC FORECAST
AND DROPPED AFTERNOON POP`S TO THE "LIKELY" CATEGORY ALL AREAS.
PREV DISCUSSION... /ISSUED 940 AM CDT MON APR 14 2014/
MESOSCALE UPDATE...MOST OF THE EARLIER SHOWERS HAVE EXITED MIDDLE
TENNESSEE, WITH A DRY WEDGE NOW BUILDING IN THAT WILL KEEP US
ESSENTIALLY RAIN-FREE FOR THE NEXT FEW HOURS. THE 14Z LAPS SOUNDING
FOR BNA SHOWS VERY LITTLE INSTABILITY IN PLACE, WITH A CAPPING
INVERSION ABOVE 900 MB. THE LATEST SURFACE MAP SHOWS A SURFACE
COLD FRONT SITUATED JUST WEST OF PAH, WITH THE FRONT PUSHING
THROUGH MIDDLE TENNESSEE DURING THE LATE AFTERNOON AND EVENING.
MODEL SOUNDINGS DO SHOW THE AFOREMENTIONED CAP ERODING JUST AHEAD
OF THE FRONT, WITH MUCH DEEPER INSTABILITY AND THUNDERSTORMS
LIKELY DEVELOPING WITH THE FRONT. LIKEWISE, THE HRRR DOES SHOW
MORE WIDESPREAD ACTIVITY DEVELOPING DURING THE AFTERNOON, SO THE
CURRENT FORECAST APPEARS TO BE ON TARGET. SPC CONTINUES TO SHOW
GENERAL THUNDERSTORMS FOR US, WITH A SLIGHT RISK AREA TO OUR
SOUTH.
PREV DISCUSSION... /ISSUED 710 AM CDT MON APR 14 2014/
UPDATE...
PER CURRENT REGIONAL RADAR MOSAIC IMAGERY AND SHORT RANGE
MODELS... LOOKS LIKE MAIN SWATH OF SHWRS/SCT TSTMS WILL MOVE E OF
MID STATE OVER THE NEXT COUPLE OF HOURS...WITH GENERALLY A BREAK
IN SHWRS EXPECTED UNTIL LATER THIS AFTERNOON. UPDATED THE SUITE OF
FORECAST PRODUCTS TO MENTION A CHANCE OF SHWRS BEHIND MAIN BAND
JUST IN CASE OF SOME DEVELOPMENT BEFORE THEN.
PREV DISCUSSION.../ISSUED 641 AM CDT MON APR 14 2014/
AVIATION 12Z DISCUSSION...
FRONTAL BOUNDARY TO MOVE ACROSS THE AREA TODAY. REDEVELOPMENT OF
SHOWER AND TSTM ACTIVITY IS POSSIBLE THIS AFTERNOON.
TONIGHT...UPPER LEVEL ENERGY WILL COME INTO PLAY WITHIN THE COLD
SECTOR BEHIND THE FROPA. THIS WILL RESULT IN A CONTINUATION OF
ELEVATED WIND SPEEDS...SHOWER CONDITIONS AND LOW CIGS.
PREV DISCUSSION... /ISSUED 331 AM CDT MON APR 14 2014/
DISCUSSION...
FORECAST REASONING WILL LEAN TOWARD A CONSENSUS MODEL SOLUTION
COMPROMISE FOR THE FORECAST PERIOD UNLESS OTHERWISE NOTED.
FORECAST QUANDARIES...CONVECTION STRENGTH TODAY...WINTRY MIX
POTENTIAL MAINLY NW PORTIONS OF MID STATE LATE TONIGHT...WIND
ADVISORY TODAY THRU TUE/FREEZE WATCH POTENTIAL WED MORNING...
AND TEMPS.
A LOT OF QUANDARIES FOR THIS FORECAST PERIOD. STARTING OFF...
EXPECTING THIS INITIAL ROUND OF SHWRS/TSTMS TO MOVE THRU THE MID
STATE THRU THE REMAINDER OF THE EARLY MORNING HRS...WITH ADDITIONAL
REDEVELOPMENT EXPECTED AT LEAST BY THIS AFTERNOON AS SFC FRONT
APPROACHES CKV AROUND 18Z AND MOVES TO JUST EAST OF NASHVILLE BY
00Z. SOME STRONG TSTMS WILL CONTINUE TO BE POSSIBLE TODAY JUST
AHEAD OF THE FRONTAL PASSAGE AND ACROSS SRN PORTIONS OF THE MID
STATE WHERE INSTABILITY AND FORCING WILL BE THE GREATEST. WILL GO
CLOSE TO MOS VALUES FOR TEMPS TODAY WITH HIGHS IN THE UPPER 60S TO
LOWER 70S. FRONT SHOULD PUSH E OF PLATEAU BY 15/06Z...WITH SOME
LINGERING MOISTURE BEHIND FRONTAL PASSAGE AHEAD OF THE UPPER LEVEL
TROUGH. THERE IS SOME POTENTIAL FOR A WINTRY MIX LATE ACROSS NW
PORTIONS OF THE MID STATE AS COLDER AIR WORKS IN...WITH TEMPS IN
THE MID 30S ACROSS THIS PORTION OF THE MID STATE...BUT UPPER 30S TO
LOWER 40S ELSEWHERE...BUT WITH MOISTURE PULLING OUT OF THIS REGION
RATHER QUICKLY AFTER 15/06Z...DO NOT FEEL AT THIS TIME CONFIDENT
ENOUGH TO MENTION...AND BELIEVE ANOTHER SET OF MODEL RUNS IS
NEEDED FOR FURTHER CLARIFICATION. EXPECTING TEMPS TO MAINLY BE IN
THE UPPER 40S ON TUE WITH BREEZY CONDITIONS CONTINUING. AS RIDGING
INFLUENCES BECOME EVEN MORE ENHANCED ACROSS THE MID STATE ON TUE
NIGHT...SKIES CLEAR...AND WINDS BECOME LIGHT...TEMPS SHOULD DROP
INTO THE MID TO UPPER 20S.
THUS...WITH THE ABOVE IN MIND...AND WITH THE SURFACE PRESSURE
GRADIENT CONTINUING TO BE STRONG THROUGH 15/00Z...AND INCREASING
EVEN MORE AFTER FRONTAL PASSAGE FROM 15/00Z-15/18Z...AND THEN
SLIGHTLY WEAKENING FROM 15/18Z-16/00Z...AND TO NOT CAUSE CONFUSION
BETWEEN SPS PRODUCT THAT NEEDS TO BE UPDATED...WILL BE ISSUING A
WIND ADVISORY THRU 16/00Z WITH BREEZY CONDITIONS WITH SUSTAINED
SOUTHERLY WINDS OF 15 TO 25 MPH WITH GUSTS TO 35 MPH POSSIBLE
THRU 15/00Z...SUSTAINED NORTH WINDS OF 20 TO 30 MPH WITH GUSTS
40-45 MPH 15/00Z-15/18Z...AND GUSTS BACK TO 35 MPH BETWEEN
15/18Z-16/00Z WITH SUSTAINED WINDS OF 15 TO 25 MPH.
THUS...AGAIN...WITH THE ABOVE IN MIND ALSO...AND WITH EXPECTED
TEMPS MAINLY BELOW 27 DEGREES...A HARD FREEZE IS BECOMING MORE
AND MORE LIKELY TO OCCUR BY WED MORNING...AND THUS WILL BE ISSUING
A FREEZE WATCH FROM MIDNIGHT UNTIL 9 AM CDT ON WED MORNING.
WILL BE GOING CLOSE TO PREVIOUS FORECAST REASONING REMAINDER OF WED
THRU THE WEEKEND WITH THE NEXT FRONTAL SYSTEM TO MOVE INTO THE MID
STATE FRI INTO FRI NIGHT...WITH TEMPS AGAIN APPROACHING SEASONABLE
NORMAL VALUES BY WEEKENDS END.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING
FOR TNZ005>011-023>034-056>066-075-077>080-093>095.
WIND ADVISORY UNTIL 7 PM CDT TUESDAY FOR TNZ005>011-023>034-
056>066-075-077>080-093>095.
&&
$$
ROSE
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1128 AM CDT MON APR 14 2014
.UPDATE...COLD FRONT HAS NOSED INTO WESTERN KY, ALTHOUGH RADAR
MOSAIC CONTINUES TO SHOW LITTLE ACTIVITY ASSOCIATED WITH THE
FRONT. THE LATEST HRRR DOES SHOW INCREASED DEVELOPMENT ACROSS
MIDDLE TENNESSEE THIS AFTERNOON, ALTHOUGH THE BULK OF THE ACTIVITY
WILL HOLD OFF UNTIL AFTER 00Z. HAVE UPDATED THE PUBLIC FORECAST
AND DROPPED AFTERNOON POP`S TO THE "LIKELY" CATEGORY ALL AREAS.
&&
.PREV DISCUSSION... /ISSUED 940 AM CDT MON APR 14 2014/
MESOSCALE UPDATE...MOST OF THE EARLIER SHOWERS HAVE EXITED MIDDLE
TENNESSEE, WITH A DRY WEDGE NOW BUILDING IN THAT WILL KEEP US
ESSENTIALLY RAIN-FREE FOR THE NEXT FEW HOURS. THE 14Z LAPS SOUNDING
FOR BNA SHOWS VERY LITTLE INSTABILITY IN PLACE, WITH A CAPPING
INVERSION ABOVE 900 MB. THE LATEST SURFACE MAP SHOWS A SURFACE
COLD FRONT SITUATED JUST WEST OF PAH, WITH THE FRONT PUSHING
THROUGH MIDDLE TENNESSEE DURING THE LATE AFTERNOON AND EVENING.
MODEL SOUNDINGS DO SHOW THE AFOREMENTIONED CAP ERODING JUST AHEAD
OF THE FRONT, WITH MUCH DEEPER INSTABILITY AND THUNDERSTORMS
LIKELY DEVELOPING WITH THE FRONT. LIKEWISE, THE HRRR DOES SHOW
MORE WIDESPREAD ACTIVITY DEVELOPING DURING THE AFTERNOON, SO THE
CURRENT FORECAST APPEARS TO BE ON TARGET. SPC CONTINUES TO SHOW
GENERAL THUNDERSTORMS FOR US, WITH A SLIGHT RISK AREA TO OUR
SOUTH.
PREV DISCUSSION... /ISSUED 710 AM CDT MON APR 14 2014/
UPDATE...
PER CURRENT REGIONAL RADAR MOSAIC IMAGERY AND SHORT RANGE
MODELS... LOOKS LIKE MAIN SWATH OF SHWRS/SCT TSTMS WILL MOVE E OF
MID STATE OVER THE NEXT COUPLE OF HOURS...WITH GENERALLY A BREAK
IN SHWRS EXPECTED UNTIL LATER THIS AFTERNOON. UPDATED THE SUITE OF
FORECAST PRODUCTS TO MENTION A CHANCE OF SHWRS BEHIND MAIN BAND
JUST IN CASE OF SOME DEVELOPMENT BEFORE THEN.
PREV DISCUSSION.../ISSUED 641 AM CDT MON APR 14 2014/
AVIATION 12Z DISCUSSION...
FRONTAL BOUNDARY TO MOVE ACROSS THE AREA TODAY. REDEVELOPMENT OF
SHOWER AND TSTM ACTIVITY IS POSSIBLE THIS AFTERNOON.
TONIGHT...UPPER LEVEL ENERGY WILL COME INTO PLAY WITHIN THE COLD
SECTOR BEHIND THE FROPA. THIS WILL RESULT IN A CONTINUATION OF
ELEVATED WIND SPEEDS...SHOWER CONDITIONS AND LOW CIGS.
PREV DISCUSSION... /ISSUED 331 AM CDT MON APR 14 2014/
DISCUSSION...
FORECAST REASONING WILL LEAN TOWARD A CONSENSUS MODEL SOLUTION
COMPROMISE FOR THE FORECAST PERIOD UNLESS OTHERWISE NOTED.
FORECAST QUANDARIES...CONVECTION STRENGTH TODAY...WINTRY MIX
POTENTIAL MAINLY NW PORTIONS OF MID STATE LATE TONIGHT...WIND
ADVISORY TODAY THRU TUE/FREEZE WATCH POTENTIAL WED MORNING...
AND TEMPS.
A LOT OF QUANDARIES FOR THIS FORECAST PERIOD. STARTING OFF...
EXPECTING THIS INITIAL ROUND OF SHWRS/TSTMS TO MOVE THRU THE MID
STATE THRU THE REMAINDER OF THE EARLY MORNING HRS...WITH ADDITIONAL
REDEVELOPMENT EXPECTED AT LEAST BY THIS AFTERNOON AS SFC FRONT
APPROACHES CKV AROUND 18Z AND MOVES TO JUST EAST OF NASHVILLE BY
00Z. SOME STRONG TSTMS WILL CONTINUE TO BE POSSIBLE TODAY JUST
AHEAD OF THE FRONTAL PASSAGE AND ACROSS SRN PORTIONS OF THE MID
STATE WHERE INSTABILITY AND FORCING WILL BE THE GREATEST. WILL GO
CLOSE TO MOS VALUES FOR TEMPS TODAY WITH HIGHS IN THE UPPER 60S TO
LOWER 70S. FRONT SHOULD PUSH E OF PLATEAU BY 15/06Z...WITH SOME
LINGERING MOISTURE BEHIND FRONTAL PASSAGE AHEAD OF THE UPPER LEVEL
TROUGH. THERE IS SOME POTENTIAL FOR A WINTRY MIX LATE ACROSS NW
PORTIONS OF THE MID STATE AS COLDER AIR WORKS IN...WITH TEMPS IN
THE MID 30S ACROSS THIS PORTION OF THE MID STATE...BUT UPPER 30S TO
LOWER 40S ELSEWHERE...BUT WITH MOISTURE PULLING OUT OF THIS REGION
RATHER QUICKLY AFTER 15/06Z...DO NOT FEEL AT THIS TIME CONFIDENT
ENOUGH TO MENTION...AND BELIEVE ANOTHER SET OF MODEL RUNS IS
NEEDED FOR FURTHER CLARIFICATION. EXPECTING TEMPS TO MAINLY BE IN
THE UPPER 40S ON TUE WITH BREEZY CONDITIONS CONTINUING. AS RIDGING
INFLUENCES BECOME EVEN MORE ENHANCED ACROSS THE MID STATE ON TUE
NIGHT...SKIES CLEAR...AND WINDS BECOME LIGHT...TEMPS SHOULD DROP
INTO THE MID TO UPPER 20S.
THUS...WITH THE ABOVE IN MIND...AND WITH THE SURFACE PRESSURE
GRADIENT CONTINUING TO BE STRONG THROUGH 15/00Z...AND INCREASING
EVEN MORE AFTER FRONTAL PASSAGE FROM 15/00Z-15/18Z...AND THEN
SLIGHTLY WEAKENING FROM 15/18Z-16/00Z...AND TO NOT CAUSE CONFUSION
BETWEEN SPS PRODUCT THAT NEEDS TO BE UPDATED...WILL BE ISSUING A
WIND ADVISORY THRU 16/00Z WITH BREEZY CONDITIONS WITH SUSTAINED
SOUTHERLY WINDS OF 15 TO 25 MPH WITH GUSTS TO 35 MPH POSSIBLE
THRU 15/00Z...SUSTAINED NORTH WINDS OF 20 TO 30 MPH WITH GUSTS
40-45 MPH 15/00Z-15/18Z...AND GUSTS BACK TO 35 MPH BETWEEN
15/18Z-16/00Z WITH SUSTAINED WINDS OF 15 TO 25 MPH.
THUS...AGAIN...WITH THE ABOVE IN MIND ALSO...AND WITH EXPECTED
TEMPS MAINLY BELOW 27 DEGREES...A HARD FREEZE IS BECOMING MORE
AND MORE LIKELY TO OCCUR BY WED MORNING...AND THUS WILL BE ISSUING
A FREEZE WATCH FROM MIDNIGHT UNTIL 9 AM CDT ON WED MORNING.
WILL BE GOING CLOSE TO PREVIOUS FORECAST REASONING REMAINDER OF WED
THRU THE WEEKEND WITH THE NEXT FRONTAL SYSTEM TO MOVE INTO THE MID
STATE FRI INTO FRI NIGHT...WITH TEMPS AGAIN APPROACHING SEASONABLE
NORMAL VALUES BY WEEKENDS END.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING
FOR TNZ005>011-023>034-056>066-075-077>080-093>095.
WIND ADVISORY UNTIL 7 PM CDT TUESDAY FOR TNZ005>011-023>034-
056>066-075-077>080-093>095.
&&
$$
ROSE
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1149 AM CDT MON APR 14 2014
.AVIATION...
CONCERNS...TIMING OF IMPROVEMENT FROM MVFR TO VFR CONDITIONS.
ISOLATED THUNDERSTORMS POSSIBLE THROUGH 21Z IN THE WACO AREA.
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ACROSS LOCATIONS
SOUTHEAST OF A LAMPASAS TO WAXAHACHIE TO PARIS LINE. THESE
SHOWERS AND THUNDERSTORMS WILL SHIFT EAST DURING THE AFTERNOON.
HAVE LEFT VCSH IN THE WACO TAF THROUGH 20Z. OTHERWISE MVFR
CEILINGS OF 2500-3000 FEET WILL IMPROVE TO VFR...3500-4000 FEET
BETWEEN 19 AND 21Z AT THE TAF SITES. SKIES WILL CLEAR LATE
AFTERNOON. GUSTY NORTHERLY WINDS AROUND 20 KNOTS WITH GUSTS TO
AROUND 30 KNOTS WILL DECREASE TO 20 TO 25 KNOTS BY 23Z AND DOWN
TO AROUND 15 KNOTS BY 02Z. NORTH WINDS WILL DECREASE TO AROUND 5
KNOTS BY 12Z. WINDS WILL BECOME WESTERLY BY 19Z TUESDAY AND
SOUTHWEST BEFORE 00Z WEDNESDAY.
58
&&
.UPDATE...
GRIDS HAVE BEEN UPDATED TO INCLUDE SEVERE THUNDERSTORM WATCH 80
FOR AREAS GENERALLY ALONG AND SOUTHEAST OF A LINE FROM KILLEEN TO
ATHENS. STORMS CONTINUE TO DEVELOP IN THESE AREAS WITH
ELEVATED CORES OCCASIONALLY PRODUCING QUARTER SIZED HAIL.
THUNDERSTORMS WILL GRADUALLY SHIFT EAST OF NORTH TEXAS ALONG WITH
THE 850MB FRONT AND THE PRIMARY UPPER TROUGH AXIS. THE WATCH IS IN
EFFECT UNTIL 5 PM CDT...BUT WE SHOULD BE ABLE TO CLEAR COUNTIES FROM
WEST TO EAST AS WARRANTED BY TRENDS.
30
&&
.PREV DISCUSSION... /ISSUED 417 AM CDT MON APR 14 2014/
08Z SURFACE ANALYSIS INDICATED A STRONG COLD FRONT MOVING
SOUTHEAST ACROSS THE CWA...LOCATED NEAR A LINE FROM ATHENS TO
WACO TO LAMPASAS. JUST TO THE NORTHWEST OF THIS FRONT...A LINE OF
SCATTERED SHOWERS AND THUNDERSTORMS WAS OBSERVED...LIKELY
ASSOCIATED WITH THE 850 MB REFLECTION OF THE COLD FRONT. AT
0830Z...NONE OF THIS ACTIVITY WAS STRONG IN NATURE...AND AS
ALLUDED TO ABOVE...IT IS ALL ELEVATED IN NATURE OVER THE FRONTAL
INVERSION. REGIONAL SURFACE OBSERVATIONS INDICATE UNSEASONABLY
COLD AIR BEHIND THE FRONT...WITH TEMPERATURES IN THE LOWER 40S
LOCATED OVER WICHITA FALLS. NORTH WINDS WERE ALREADY RELATIVELY
STRONG BEHIND THE FRONT...WITH MANY LOCATIONS OBSERVING WINDS IN
THE 20 TO 25 MPH RANGE EARLY THIS MORNING.
THIS MORNING...WENT AHEAD AND CANCELLED THE SEVERE THUNDERSTORM
WATCH IN COORDINATION WITH THE SPC AND WFO SHV AS THE COLD FRONT
HAD UNDERCUT ALL ONGOING CONVECTION. THIS DOES NOT MEAN IT/S
IMPOSSIBLE TO GET STRONG STORMS THIS MORNING...HOWEVER THE ONLY
STRONG TO MARGINALLY SEVERE STORM HAZARD ASSOCIATED WITH ELEVATED
STORMS IS GOING TO BE IN THE FORM OF HAIL. RAP FORECAST SOUNDINGS
INDICATE THE PRESENCE OF 1000-1500 J/KG OF MUCAPE AVAILABLE FOR
THESE ELEVATED STORMS. DEEP LAYER SHEAR VALUES LOOK
IMPRESSIVE...BUT ARE NOT REALLY RELEVANT FOR THIS ACTIVITY AS THE
BULK OF THE CONTRIBUTION TO THE HIGHER SHEAR VALUES OCCURS BELOW
THE FRONTAL INVERSION. DEEP LAYER BULK SHEAR CALCULATIONS INDICATE
ABOUT 60 KTS OF SHEAR...WHILE EFFECTIVE BULK SHEAR IS MORE
REALISTICALLY AROUND 25 KTS. AS A RESULT...STRONG...BUT LIKELY
UNORGANIZED ELEVATED CONVECTION IS POSSIBLE THIS MORNING. BASED ON
THE RADAR PRESENTATION OF STORMS SO FAR EARLY THIS
MORNING...CHANCES ARE NO LARGE HAIL WILL FALL ACROSS THE
CWA...HOWEVER IF IT DOES OCCUR...HAIL WILL LIKELY BE CLOSE TO 1
INCH OR QUARTER SIZE IN DIAMETER.
REMAINDER OF TODAY...THE 850 MB FRONT WILL SLIDE SOUTHEAST OF THE
CWA BY LATE THIS MORNING...TAKING ALL THUNDERSTORM CHANCES
SOUTHEAST OUT OF THE AREA IN ITS WAKE. RELATIVELY STRONG ISENTROPIC
DOWNGLIDE/COLD AIR ADVECTION WILL DOMINATE THE LOWER TROPOSPHERE
IN THE WAKE OF THIS FRONT. A STRONG UPPER LEVEL LOW PRESSURE
SYSTEM WILL MOVE FROM WEST TO EAST OVER THE SOUTH PLAINS
TODAY...WHICH WILL SPREAD SOME STRONG LARGE SCALE FORCING FOR
ASCENT OVER THE CWA THIS AFTERNOON. HOWEVER...THE LARGE SCALE
FORCING FOR ASCENT ASSOCIATED WITH THIS UPPER LOW IS NOT EXPECTED
TO PENETRATE MUCH DEEPER THAN THE MIDDLE TROPOSPHERE TODAY BECAUSE
THE MIDDLE TO LOW TROPOSPHERE WILL BE DEFINED BY HIGH STATIC
STABILITY. A THERMODYNAMICALLY STABLE LAYER RESISTS VERTICAL
MOTIONS...AND THEREFORE SHOULD PREVENT ANY ADDITIONAL
PRECIPITATION FROM DEVELOPING OVER THE CWA TODAY ASSOCIATED WITH
THIS UPPER LOW. THIS IS SUCH A STRONG UPPER TROUGH THAT IT WOULD
BE A HUGE SURPRISE TO SEE SOME WEAK RADAR RETURNS DEVELOP OVER THE
CWA EARLY THIS AFTERNOON...BUT THE COLD FRONT PUSHING THROUGH THE
AREA JUST LOOKS TOO STRONG AND COLD TO ALLOW FOR MUCH LIFT TO
OCCUR WHERE WE WOULD NEED IT TO GET RAIN SHOWERS...THAT BEING THE
MID TO LOWER TROPOSPHERE.
ASIDE FROM PRECIPITATION CONCERNS...BEHIND THE FRONT WE SHOULD
JUST SEE STRONG NORTH WINDS AND COLD AIR ADVECTION THROUGHOUT THE
DAY TODAY. TEMPERATURES ARE EXPECTED TO INCREASE INTO THE LOWER TO
MID 50S BY LATE THIS AFTERNOON DESPITE THE STRONG COLD AIR
ADVECTION AS SKIES CLEAR OUT RAPIDLY BEHIND THE PASSAGE OF THE
UPPER TROUGH. EVEN THOUGH THE AIR BEHIND THE FRONT WILL REMAIN
COLD...THE SUN ANGLE IS GETTING TOO HIGH FOR US NOT TO HEAT UP A
BIT EVEN WITH JUST A FEW HOURS OF SUNSHINE. A WIND ADVISORY
REMAINS IN EFFECT FOR THE ENTIRE AREA TODAY DUE TO NORTH WINDS OF
25 TO 30 MPH BEHIND THE FRONT. WINDS SHOULD DIMINISH AN HOUR OR
TWO AFTER SUNSET AS HIGH PRESSURE BEGINS TO MOVE INTO THE REGION.
TONIGHT...HIGH PRESSURE IS EXPECTED TO SLIDE SOUTH-SOUTHEAST
ACROSS TEXAS FROM THE TX PANHANDLE TONIGHT. THIS WILL RESULT IN
NEARLY CALM WINDS ACROSS WEST CENTRAL TEXAS...AND LIGHT NORTHERLY
WINDS TO THE EAST. LIGHT WINDS AND CLEAR SKIES WILL MAKE FOR AN
IDEAL RADIATIONAL COOLING ENVIRONMENT RESULTING IN TEMPERATURES
FALLING INTO THE UPPER 20S TO MID 30S ACROSS THE CWA. YES...YOU
READ THAT CORRECTLY...PARTS OF NORTH AND CENTRAL TEXAS ARE
EXPECTED TO FALL BELOW FREEZING TONIGHT INTO TUESDAY MORNING. THIS
IS PUSHING RECORD TERRITORY FOR A LATE FREEZE WHICH IS QUITE
REMARKABLE CONSIDERING RECORDS HAVE BEEN KEPT SINCE THE LATE 1800S
TO EARLY 1900S...SO WE ARE LOOKING AT AN EVENT THAT HAS A RETURN
INTERVAL OF OVER 100 YEARS...FOR NORTH AND CENTRAL TEXAS AT LEAST.
AS A RESULT...THIS FREEZE...ASSUMING IT OCCURS AS FORECAST...HAS
THE POTENTIAL TO DO QUITE A BIT OF DAMAGE TO OUTDOOR PLANTS AS
MOST FOLKS WOULD NOT HAVE WAITED THIS LONG TO GET THEIR SPRING
PLANTING TAKEN CARE OF. AT ANY RATE...THIS IS WHY FREEZE WARNINGS
ARE ISSUED...TO GIVE FOLKS A CHANCE TO PROTECT THEIR PLANTS.
A FREEZE WARNING IS IN EFFECT FROM 1 AM TO 10 AM TONIGHT/TUESDAY
MORNING FOR LOCATIONS ALONG AND NORTHWEST OF A LINE FROM SULPHUR
SPRINGS TO KELLER TO WACO TO LAMPASAS. LOCATIONS JUST SOUTHEAST OF
THIS LINE GENERALLY HAVE FORECAST LOWS AT 33 DEGREES...SO THIS
WARNING MAY BE EXPANDED BASED ON HOW WARM WE GET THIS AFTERNOON
AND BASED ON NEW MODEL GUIDANCE THROUGHOUT THE DAY.
FORTUNATELY...MOST LOCATIONS IN THE FREEZE WARNING SHOULD SEE LOWS
FALL JUST BELOW FREEZING...GENERALLY 30 TO 32 DEGREES.
TEMPERATURES FALLING INTO THE UPPER 20S IS MORE LIKELY NORTH OF
INTERSTATE 30...NEAR THE RED RIVER.
TEMPERATURES ARE MORE LIKELY TO FALL BELOW FREEZING IN RURAL AREAS
MORE SO THAN URBAN AREAS. THE URBAN HEAT ISLAND EFFECT WILL KEEP
MOST OF THE CONCRETED AREAS OF THE METROPLEX ABOVE FREEZING.
TARRANT COUNTY IS INCLUDED IN THE FREEZE WARNING ANYWAYS BECAUSE
THE FAR NORTH AND WESTERN PORTIONS OF THE COUNTY...OUTSIDE OF THE
820 LOOP...ARE MORE LIKELY TO SEE FREEZING TEMPERATURES.
TEMPERATURES ARE EXPECTED TO CLIMB ABOVE FREEZING AREA WIDE AFTER
10 AM TUESDAY MORNING.
FROST IS POSSIBLE IN AREAS NOT INCLUDED IN THE FREEZE WARNING...SO
EVEN IF YOU ARE NOT IN THE FREEZE WARNING AT THIS TIME...IT MAY BE
PRUDENT TO PROTECT YOUR PLANTS ANYWAYS AS A PRECAUTION. THE AIR IS
EXPECTED TO BE VERY DRY...SO WIDESPREAD FROST IS NOT LIKELY...BUT
IT MAY BE BETTER TO BE SAFE THAN SORRY.
REMAINDER OF THE FORECAST...WE WILL WARM UP AFTER TUESDAY...WITH
NO MORE POTENTIAL FROSTS OR FREEZES IN THE FORECAST THROUGH NEXT
WEEKEND. TUESDAY NIGHTS LOWS WILL BE WELL BELOW NORMAL AGAIN...BUT
SHOULD FALL INTO THE MID TO UPPER 30S AT WORST. BY
WEDNESDAY...SOUTH WINDS WILL HELP BRING DEW POINTS BACK UP INTO
THE MID TO UPPER 40S...BRINGING ABOUT A RETURN TO MORE SEASONAL
TEMPERATURES DURING THE DAYTIME AND OVERNIGHT.
OUR NEXT CHANCE OF RAIN STILL LOOKS TO BE THURSDAY...ASSOCIATED
WITH AN UPPER LEVEL TROUGH PROGGED TO MOVE OVER THE SOUTHERN
PLAINS THURSDAY AFTERNOON. HOWEVER...THE ECMWF AND GFS BOTH KEEP
THE BULK OF THE UPPER LEVEL FORCING FOR ASCENT ASSOCIATED WITH
THIS TROUGH NORTH OF THE CWA. ASSUMING THIS VERIFIES...THIS DOES
NOT USUALLY BODE WELL FOR PRECIPITATION CHANCES...EVEN WITH A WEAK
COLD FRONT PUSHING SOUTHEAST ACROSS THE CWA THURSDAY
AFTERNOON/EVENING. THE LOSS OF UPPER LEVEL DYNAMICS USUALLY MAKES
PRECIPITATION ALONG COLD FRONTS ISOLATED AT BEST. THE CANADIAN IS
FURTHER SOUTH WITH THIS UPPER TROUGH...AND THEREFORE HAS MUCH MORE
PRECIPITATION FOR THE CWA. WILL CONTINUE TO MONITOR THE EVOLUTION
OF THIS TROUGH IN FUTURE FORECASTS...HOWEVER FOR NOW JUST KEPT
POPS IN THE 20 TO 30 PERCENT RANGE IN LINE WITH THE GFS/ECMWF
SOLUTION.
AFTER THURSDAY...OUR NEXT SHOT AT RAIN LOOKS TO BE SATURDAY NIGHT
INTO SUNDAY...AS ALL GUIDANCE INDICATES AN UPPER LEVEL TROUGH WILL
MOVE OVER THE SOUTHWESTERN CONUS AND TOWARDS NORTH TX AT THAT
TIME. THE GFS IS THE MOST AGGRESSIVE WITH TAPPING INTO SOME
TROPICAL PACIFIC MOISTURE IN THE UPPER TROPOSPHERE COURTESY OF THE
SUB-TROPICAL JET. AS A RESULT THE GFS GIVES THE CWA A
GOOD...WIDESPREAD ONE HALF TO ONE INCH OF RAINFALL FROM SATURDAY
NIGHT THROUGH SUNDAY. WILL NOT BITE OFF ON THIS SOLUTION QUITE
YET...BUT IT IS A GOOD SIGN THAT AT LEAST ALL MODELS HAVE SOME
VERSION OF THIS TROUGH OVER THE SOUTHWESTERN CONUS. IF THIS
CONSISTENT CONTINUES...POPS WILL BE INCREASED AREA WIDE FOR
SATURDAY NIGHT INTO SUNDAY. THIS DOES NOT LOOK TO BE A GOOD SEVERE
WEATHER SET UP FOR NOW...SO A GOOD WIDESPREAD RAINFALL WITH
EMBEDDED THUNDERSTORMS IS WHAT IS EXPECTED AT THIS TIME. WE WILL
SEE HOW THINGS CHANGE AS WE GET CLOSER TO NEXT WEEKEND OF COURSE.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 55 34 63 42 66 / 10 5 0 0 0
WACO, TX 56 33 63 36 67 / 30 0 0 0 0
PARIS, TX 51 30 59 36 64 / 20 5 0 0 0
DENTON, TX 53 29 62 38 66 / 10 5 0 0 0
MCKINNEY, TX 53 30 62 38 65 / 10 5 0 0 0
DALLAS, TX 56 35 63 42 66 / 10 5 0 0 0
TERRELL, TX 55 33 62 37 65 / 20 5 0 0 0
CORSICANA, TX 54 33 61 38 66 / 30 5 0 0 0
TEMPLE, TX 58 33 64 36 68 / 30 0 0 0 0
MINERAL WELLS, TX 55 32 63 37 69 / 10 0 0 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 1 AM TO 10 AM CDT TUESDAY FOR TXZ091>095-
100>107-115>118-129>133-141>145-156-157-159.
WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR TXZ091>095-100>107-
115>123-129>135-141>148-156>162-174-175.
&&
$$
58/30
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
140 PM EDT MON APR 14 2014
.SYNOPSIS...
A COLD FRONT FROM THE GREAT LAKES TO SE TX WILL SHIFT EAST TODAY
AND TONIGHT CROSSING THE MID ATLANTIC REGION ON TUESDAY. BEHIND
THE FRONT HIGH PRESSURE WILL BUILD IN FOR WEDNESDAY THROUGH
FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 105 PM EDT MONDAY...
UPDATED FORECAST TO REFLECT RADAR TRENDS AND HRRR APPEARS TO
HANDLE THINGS WELL IN THE NEAR TERM. THIS MEANS LESS THREAT OF
RAIN SHOWERS OVER THE AREA...THEN SHOWERS INCREASE BY AFTER 3-5PM
AHEAD OF VORT OVER NRN GA EARLY. THUNDER SITUATION STILL MARGINAL
BUT ENOUGH INSTABILITY IN THE MID LEVELS FOR ISOLATED THREAT
MAINLY SOUTHEAST AND SOUTHWEST CWA.
PREVIOUS VALID DISCUSSION...
CUT HIGH TEMPS BACK A FEW DEGREES ACROSS THE MOUNTAINS PER LACK
OF SUN AND SHOWERS MOVING IN.
MUCH BETTER SYNOPTIC SCALE LIFT AFTER 00Z/8PM THIS EVENING. AS
THE COLD FRONT APPROACHES LATE TONIGHT...SURFACE AND LOW LEVEL
WINDS BACK...ADDING THE SOUTHEAST UPSLOPE COMPONENT TO THE STRONG
FORCING. LARGEST PRECIPITATION AMOUNTS WILL BE AFTER MIDNIGHT.
FRONT DOES NOT REACH THE FAR WESTERN PART OF THE FORECAST AREA
BEFORE 12Z/8AM. STAYED CLOSER TO THE WARMER GUIDANCE FOR OVERNIGHT
LOWS. THE LOW LEVEL JET INCREASES OVERNIGHT. HIGHER ELEVATIONS MAY
HAVE GUSTS OF 25 TO 30 MPH.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
AS OF 400 AM EDT MONDAY...
A STRONG COLD FRONT WILL MAKE ITS WAY ACROSS THE FORECAST AREA
BEGINNING TUESDAY MORNING...AND THEREFORE WILL HAVE SEVERAL THINGS
TO KEEP AN EYE. MODELS CONTINUE TO INDICATE A SOUTHWESTERLY 55KT LOW
LEVEL JET DEVELOPING AHEAD OF THE FRONT. INSTABILITY AHEAD OF THE
FRONT WILL BE MARGINAL...RESULTING IN MAINLY HEAVY SHOWER ACTIVITY
WITH ONLY ISOLATED THUNDER AS THE FRONT PASSES. HOWEVER...WITH THE
JET BLOWING JUST OFF THE SURFACE OVER THE MOUNTAINS...WOULD NOT BE
SURPRISED TO SEE SOME OF THE MORE INTENSE SHOWER ACTIVITY DRAW THE
STRONGER WINDS DOWN TO THE GROUND LEVEL.
HIGH PRESSURE WILL BUILD IN QUICKLY AFTER THE COLD FRONT PASSES...
RESULTING IN A ROUGHLY 10MB PRESSURE GRADIENT ACROSS THE FORECAST
AREA FROM MID AFTERNOON THROUGH ALMOST MIDNIGHT. EXPECT STRONG
NORTHWEST WINDS WITH 40 TO 50 MPH GUSTS ACROSS THE MOUNTAINS...WITH
THE STRONGEST GUSTS FOUND ALONG THE BLUE RIDGE PARKWAY SOUTH OF
ROANOKE. THESE GUSTS...WHEN COMBINED WITH PROLONGED RAINFALL...WILL
LIKELY BE ENOUGH TO BRING DOWN A FEW TREES...AND RESULT IN LOCALIZED
POWER OUTAGES.
RAINFALL WILL BE WIDESPREAD AND HEAVY AT TIMES...WITH A STORM TOTAL
AMOUNT OF OVER AN INCH FOR THE ENTIRE FORECAST AREA...WITH AROUND 2
INCHES EXPECTED ALONG THE BLUE RIDGE. MAY SEE LOCALIZED MINOR
FLOODING ISSUES DEVELOP WHERE BANDS OF HEAVY RAIN PASS REPEATEDLY
OVER THE SAME LOCATIONS. RAINFALL MAY ALSO PUSH SOME RIVERS TO
BANKFULL OR MINOR FLOOD LATER IN THE WEEK.
FOR THE FIRST FEW HOURS AFTER FRONTAL PASSAGE...TEMPERATURES WILL
PLUMMET AT A RATE OF 6 TO 9 DEGREES PER HOUR. EXPECT TEMPERATURES TO
APPROACH FREEZING FROM SOUTHEAST WEST VIRGINIA THROUGH THE NORTH
CAROLINA MOUNTAINS BY EARLY EVENING...ALLOWING RAIN SHOWERS TO
CHANGE OVER TO SNOW. WHILE WARM GROUND TEMPERATURES WILL CAUSE SNOW
TO MELT ON CONTACT ACROSS MANY AREAS...MAY SEE UP TO A HALF INCH OF
SNOW ACCUMULATE ALONG OUR MORE PROMINENT WEST FACING SLOPES BEFORE
SNOW SHOWERS END OFF SHORTLY AFTER MIDNIGHT WEDNESDAY.
NEXT WE GET TO DEAL WITH SUB FREEZING TEMPERATURES AREAWIDE BY
SUNRISE WEDNESDAY. EXPECT OVERNIGHT LOWS TO RANGE FROM THE MID 20S
ACROSS SOUTHEAST WEST VIRGINIA TO THE LOW 30S ACROSS THE SOUTHSIDE.
PRECAUTIONS SHOULD BE TAKEN TO PROTECT ANY PLANTS THAT MAY BE KILLED
BY FREEZING TEMPERATURES.
HIGH PRESSURE WILL PASS FROM THE GREAT LAKES TO NEW ENGLAND ON
WEDNESDAY...AND WILL BUILD SOUTHWARD ALONG THE EASTERN FACE OF THE
APPALACHIANS. THE NORTHEASTERLY WIND FLOW AROUND THE HIGH WILL KEEP
COOL CONDITIONS IN PLACE HEADING INTO THE SECOND HALF OF THE
WORKWEEK...WITH FREEZING TEMPERATURES LIKELY AGAIN WEDNESDAY NIGHT.
A GRADUAL WARM UP WILL TAKE PLACE THURSDAY AS WINDS ALOFT BEGIN TO
SHIFT SOUTHWESTERLY AGAIN.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 200 PM EDT SATURDAY...
EXPECT HIGH PRESSURE TO REMAIN IN CONTROL OF THE WEATHER PATTERN FOR
FRIDAY. A COLD FRONT WILL APPROACH FROM THE WEST FRIDAY NIGHT INTO
SATURDAY. GENERALLY FOLLOWED WPCGUIDE FOR POPS. STILL LOOKS LIKE
THE BEST CHANCE FOR WIDESPREAD RAIN WILL OCCUR ON FRIDAY NIGHT
INTO SATURDAY. LEANED TOWARDS THE ECENS MEAN WITH HANDLING THE
SOUTHERN STREAM SYSTEM AND ITS MOISTURE. TEMPERATURES MODERATE
TOWARD NEXT WEEKEND CLOSER TO NORMAL.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 130 PM EDT MONDAY...
VFR CIGS THIS AFTERNOON WILL SINK TO MVFR THEN IFR THIS EVENING
WITH INCREASING THREAT OF SHOWERS. VSBYS IN THE HEAVIER SHOWERS
SHOULD DROP TO HIGH END IFR/LOW END MVFR. A TSRA IS POSSIBLE BUT
NOT ENOUGH COVERAGE/THREAT OVERALL TO HAVE IN TAFS.
GUSTY SOUTH WINDS THIS AFTERNOON SHOULD WEAKEN THIS EVENING.
OVERNIGHT...FRONT WILL APPROACH THE WEST AND FINALLY EXIT EAST OF
THE MTNS BY 15Z TUESDAY...AND OUT EAST IN THE AFTERNOON. WILL SEE
MODERATE SHOWERS AND AT TIMES HEAVIER DOWNPOURS. ON AVERAGE
VSBYS/CIGS WILL BE IN IFR/MVFR. ONCE FRONT PASSES THE BLF AREA
SHOULD SEE LOWER CIGS UPSLOPE EFFECT...AND INTO LWB AS WELL WITH
BUFKIT SOUNDINGS AND GUIDANCE SUGGESTING CIGS BELOW 5H FEET.
EXPECT RAINS AND SOME THUNDER TO LINGER EAST OF THE BLUE RIDGE
INTO TUESDAY EVENING. COLDER AIR WILL BRING TEMPS DOWN FAST IN THE
MOUNTAINS BY TUESDAY EVENING WHERE SOME SNOW SHOWERS ARE POSSIBLE.
WINDS TO BE AN ISSUE AS WELL BEHIND FRONT TUESDAY INTO TUESDAY
NIGHT WITH GUSTS TO 40 KNOTS POSSIBLE. SMALL WINDOW AS HIGH
PRESSURE BUILDS IN WEDNESDAY MORNING.
MAY SEE RESIDUAL MOISTURE WEDNESDAY KEEPING MVFR CIGS OVER THE
MOUNTAINS. VFR THEN EXPECTED THURSDAY WITH HIGH PRESSURE RIDGING
IN FROM OFF NEW ENGLAND BETWEEN THE EXITING FRONT OFFSHORE AND THE
NEXT COLD FRONT TO THE NW. NEXT COLD FRONT APPROACHES FROM THE
WEST FRIDAY BUT APPEARS SLOW ENOUGH TO MAINTAIN VFR DURING THE DAY
FOR NOW.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS/WP
NEAR TERM...AMS/WP
SHORT TERM...NF
LONG TERM...KK
AVIATION...WP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1220 PM CDT MON APR 14 2014
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 345 AM CDT MON APR 14 2014
MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES TODAY AND
THEN TUESDAY NIGHT INTO WEDNESDAY.
SURFACE ANALYSIS SHOWS AN AREA OF LOW PRESSURE OVER NORTHERN
ILLINOIS. LOCAL AND REGIONAL RADARS SHOWING THE DEFORMATION BAND
OF PRECIPITATION ON THE NORTHWEST SIDE OF THE LOW EXTENDS FROM
SOUTHERN IOWA ACROSS THE AREA INTO EASTERN LAKE SUPERIOR. COLDER
AIR HAS FILTERED IN AND CHANGED MOST OF THE PRECIPITATION OVER TO
SOME LIGHT SNOW. THE PRECIPITATION IS MOVING TO THE NORTHEAST AND
THE 14.05Z HRRR SEEMS TO HAVE A GOOD HANDLE ON THE CURRENT
SITUATION. IT INDICATES THAT BY 12Z THE BACK EDGE OF THE
PRECIPITATION COMING OUT OF SOUTHERN IOWA WILL HAVE SHIFTED INTO
SOUTHERN WISCONSIN WITH THE WESTERN EDGE INTO THE WESTERN AND
CENTRAL PARTS OF WISCONSIN. WILL ADJUST THE MORNING SNOW CHANCES
BASED ON RADAR TRENDS...BUT EXPECT THAT THE MAJORITY OF THE
ACTIVITY SHOULD BE EAST OF THE FORECAST AREA BY 12Z AND THEN WHAT
IT IS LEFT WILL QUICKLY DISSIPATE BY THE MID MORNING HOURS.
HIGH PRESSURE WILL THEN BUILD IN OVER THE UPPER MIDWEST AND LINGER
INTO TUESDAY BEFORE DEPARTING TO THE NORTHEAST. THE HIGH WILL HELP
TO KEEP TEMPERATURES BELOW NORMAL WITH HIGHS TODAY ONLY IN THE
30S FOR THE ENTIRE AREA AND THEN IN THE 30S AND 40S FOR TUESDAY.
THE NEXT CHANCE FOR SOME PRECIPITATION WILL START TO COME IN
TUESDAY NIGHT AND CONTINUE INTO WEDNESDAY. THIS WILL BE IN
RESPONSE TO A SHORT WAVE TROUGH THAT WILL CROSS THE NORTHERN
ROCKIES TUESDAY NIGHT AND MOVE OUT OVER THE UPPER MIDWEST
WEDNESDAY. THE BEST PV ADVECTION IN THE 500-300 MB LAYER IS
EXPECTED TO REMAIN NORTHWEST OF THE AREA THROUGH WEDNESDAY...BUT
THE WAVE SHOULD STILL BE ABLE TO PRODUCE AT LEAST SOME WEAK PV
ADVECTION OVER THE NORTHWEST SECTIONS OF THE FORECAST AREA. LOW
PRESSURE AT THE SURFACE IS EXPECTED TO MOVE EAST ACROSS SOUTH
DAKOTA DURING THE DAY WEDNESDAY WITH A WARM FRONT EXTENDING EAST
INTO WISCONSIN. WEAK FRONTOGENESIS IN THE 1000-700 MB LAYER IS
EXPECTED TO DEVELOP ALONG AND NORTH OF THE WARM FRONT ACROSS
MINNESOTA AND WISCONSIN. THE WARM AIR ADVECTION AHEAD OF THE SHORT
WAVE TROUGH AND SURFACE LOW IS EXPECTED TO PRODUCE 5 TO 8 UBAR/S
OF UP GLIDE ON THE 290K ISENTROPIC SURFACE. WITH THE FORCING FROM
THE SHORT WAVE TROUGH AND THE LOW LEVEL FRONTOGENESIS AND
ISENTROPIC UP GLIDE...EXPECT TO SEE PRECIPITATION BEGIN TO DEVELOP
ALONG AND NORTH OF THE WARM FRONT LATE TUESDAY NIGHT AND CONTINUE
INTO WEDNESDAY. WILL START OUT WITH SOME SMALL CHANCES ALONG AND
NORTH OF INTERSTATE 94 LATE TUESDAY NIGHT AND THEN SPREAD THE
CHANCES SOUTH TO ABOUT THE IOWA/MINNESOTA BORDER WEDNESDAY WHILE
INCREASING TO 50 PERCENT ACROSS THE FAR NORTH. BUFKIT SOUNDINGS
INDICATE THAT ICE WILL BE PRESENT IN THE CLOUDS AND THERE SHOULD
NOT BE A WARM LAYER TO DEAL WITH...SO THE PRECIPITATION TYPE
SHOULD BE CONTROLLED BY THE BOUNDARY LAYER TEMPERATURES. WILL
START WITH ALL SNOW TUESDAY NIGHT GOING TO RAIN WEDNESDAY AS
READINGS WARM INTO THE 40S AND 50S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 AM CDT MON APR 14 2014
SLOW AND COMPLICATED UPPER AIR PATTERN WILL KEEP THE PRECIPITATION
CHANCES IN THE FORECAST THROUGH THE WEEKEND. ONCE THE FIRST SHORT
WAVE TROUGH MOVES PAST THE REGION WEDNESDAY NIGHT...ALL THE MODELS
SHOW A CUT OFF LOW FORMING OVER SOUTHERN SASKATCHEWAN FROM A
STRONG NORTHERN STREAM SHORT WAVE TROUGH COMING DOWN FROM THE
NORTHERN CANADA. THIS IS EXPECTED TO KEEP THE MEAN LONG WAVE
TROUGH ALONG AND EAST OF THE ROCKIES WITH SEVERAL SHORT WAVE
TROUGHS COMING THROUGH THIS LONG WAVE TROUGH. THE CLOSED LOW
SHOULD THEN OPEN UP AND START TO MOVE EAST WITH THE LONG WAVE
TROUGH PASSING OVER FOR THE WEEKEND. WITHIN THIS EXTENDED PERIOD
OF PRECIPITATION CHANCES...THE BEST CHANCES LOOK TO OCCUR THURSDAY
NIGHT INTO FRIDAY WHEN A STRONG SHORT WAVE TROUGH IS SHOWN BY THE
MODELS TO MOVE ACROSS THE REGION. TEMPERATURES STILL LOOK TO BE
COOL ENOUGH FOR SNOW OR A RAIN/SNOW MIX AT NIGHT GOING TO RAIN
DURING THE DAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1220 PM CDT MON APR 14 2014
LOWER CLOUDS FLIRTING WITH THE MVFR/VFR THRESH-HOLD HAVE BEEN SLOWLY
CLEARING THE TAF SITES THRU THE MORNING. ONCE THESE ARE SOUTHEAST OF
THE TAF SITES BY 19-20Z...GOOD VFR CONDITIONS EXPECTED THRU TONIGHT/
TUE MORNING AS COLD/DRY CANADIAN HIGH PRESSURE DRIFTS EAST ACROSS
THE UPPER MIDWEST. THE BRISK NORTH TO NORTHWEST WINDS WILL PERSIST
THRU MID AFTERNOON...THEN DIMINISH RATHER QUICKLY BY OR AFTER 23Z AS
THE SFC RIDGE AXIS APPROACHES/MOVES ACROSS THE AREA AND THE MIXED
DEPTH DECREASES AROUND SUNSET.
&&
.HYDROLOGY...
ISSUED AT 345 AM CDT MON APR 14 2014
PARTS OF SOUTHWEST WISCONSIN RECEIVED BETWEEN 2 AND 4 INCHES OF
RAIN OVER THE WEEKEND. THIS HAS RESULTED IN SATURATED SOILS AND
RUNOFF INTO AREAS STREAMS. THIS HAS RESULTED IN MAINLY IN BANK
RISES BUT THE LATEST FORECASTS INDICATE SOME MINOR FLOODING IS
POSSIBLE ALONG THE KICKAPOO IN THE VICINITY OF READSTOWN. SOME
FLOODING LATER THIS WEEK IS POSSIBLE ALONG THE MISSISSIPPI RIVER
AS RUNOFF FROM THE SNOWMELT UPSTREAM AND THE RECENT RAINS MOVES
DOWNSTREAM.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...DAS
HYDROLOGY...04