Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/07/15
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
946 PM PDT Sat Apr 4 2015
.Synopsis...
Periods of rain and mountain snow with below normal temperatures
Sunday into Wednesday. Warmer and drier weather for the latter half
of the week.
&&
.Discussion...
High and mid-level clouds streaming over NorCal this evening. A
few sprinkles and light showers over Shasta county and the northern
Sierra. Trace amounts at Redding and Red Bluff and 0.05 at Butte
Meadows(Tehama county 4000 feet). Initial disturbance is still west
of Eureka and running a few hours slower versus afternoon
guidance. HRRR is showing showers filling in over much of the
southern and central Sac valley after 8am and shifting over the
Sierra through the morning. Activity over the northern Sac valley
will be a bit more convective and showery in nature. Current
forecast is on track and no evening update will be needed.
.Previous Discussion...
Norcal in for a good ol` one/two punch in the wx for the next few
days.
Challenges in the forecast are QPF/Snow levels and most
importantly...timing of the precip. Today`s models have slowed the
onset of precip in Norcal on Sun and have made some adjustments for
the afternoon package in the timing of the WSW as well.
Short wave energy vcnty of 40n/140w rotating under the NErn Pac
upper low will begin to impact Norcal early Sun morning. Although
some WAA precip may develop over the Siernev overnight...this is
expected to be minimal/very light and spotty at best. TPW is below
the .80" necessary to produce significant precip in Norcal given the
duration of this system...and relatively low for a WAA precip
pattern. The dry sub-cloud layer will also retard onset of
precip...so anything overnight is expected to be very light.
However...as large scale ascent and CAA increases on Sun with the
incoming short wave energy...precip will become widespread with the
higher resolution QPF progs suggesting Sun afternoon will be the
primary period of precip to warrant a WSW in the Siernev. Precip may
not make it as far south of the YNP area until late Sun afternoon or
early evening...so hikers may have most of the day without
encountering precip.
The dry air mass will also lead to wet-bulb cooling which will make
snow level forecasting a challenge. We are already dealing with a
cold air mass as evidenced by the open-cellular cumulus over the
NErn Pac and a cold upper level low. The temps are not too highly
anomalous however...as the return interval of heights/temps
depending on which standard pressure surface you look at...ranges
from a 1 to 5 year return period on the NAEFS. Given the WBZs drop
to 2000-2800 ft in our CWA Sun morning...the initial snow level may
be lower in the morning...and then rise slightly as the air mass
moistens. By Sun afternoon the WBZs rise to 3000-4000 ft...so our
thinking of 3500 ft snow levels for the Siernev and 2000-2500 for
Shasta Co look reasonable at this time.
System #1 decreases/winds downs Sun evening...but wx system #2 will
follow on it`s heels for Mon/Tue. The upper low over the NErn Pac is
progged to drop down over the region Tue. It will likely bring
precip to the Coastal Range and Wrn half of the CWA on Mon...before
spreading across the entire CWA on Tue. Large scale ascent forecast
to be much stronger with storm #2 than #1 with the potential for a
wetter/stronger storm. The strongest upward vertical motion is
forecast around the 12z Tue time frame generally in the valley...
before shifting into the Siernev around midday Tue. Depth of
moisture up to 400 mbs will make it difficult for significant breaks
in cloud cover for stronger surface heating...but the cold pool
aloft will steepen lapse rates with the potential for thunder/small
hail or graupel storms in the valley and Siernev foothills primarily
Tue afternoon/early evening. This storm has the potential for a
watch/warning product in future forecasts...including all of our mtn
zones...but will deal with storm #1 first.
Strong cyclonic flow in the wake of this system on Wed will keep
clouds and at least a chance of showers over the Siernev during the
day. JHM
.Extended Discussion (Wednesday through Saturday)
Lingering showers possible over the mountains of Eastern Shasta,
Plumas, and Sierra Nevada Wednesday, then dry and warmer weather
expected Thursday into Saturday as Pacific upper ridge moves
inland.
&&
.Aviation...
Dtrtg conds Sun as Pac stm movs into Intr NorCal. Mnly VFR conds
thru abt 17z Sun then wdsprd MVFR with areas IFR, lcl LIFR omtns,
in pcpn. Sn lvls arnd 025 Shasta mtns to 035 amsl ovr Siernev.
Isold tstms with sml hail poss mnly n of I-80 Sun aftn/eve. Areas
Sly sfc wnd gsts to 25 kts Sun aftn with S-SW sfc wnd gsts up to
40 kts poss ovr hyr mtn trrn.
&&
.STO Watches/Warnings/Advisories...
winter weather advisory from 8 am sunday to midnight pdt sunday
night above 3500 feet in the western plumas county/lassen park.
winter weather advisory from noon sunday to midnight pdt sunday
night above 3500 feet in the west slope northern sierra nevada.
&&
$$
AREA FORECAST DISCUSSION
NWS PUEBLO CO
906 PM MDT MON APR 6 2015
.UPDATE...
ISSUED AT 903 PM MDT MON APR 6 2015
UPDATED FOR EXPIRATION OF RED FLAG WARNING. RH STILL VERY LOW MOST
LOCATIONS...BUT WINDS HAVE DIMINISHED ENOUGH TO LET WARNING EXPIRE
ON SCHEDULE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 245 PM MDT MON APR 6 2015
...SHORT TERM CONCERN REMAINS CRITICAL FIRE WEATHER CONDITIONS...
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS INDICATING A DEEP
SOUTHWESTERLY FLOW PATTERN ACROSS THE REGION WITH AN UPPER LOW AND
BROAD TROUGH JUST OFFSHORE THE PAC NORTHWEST COAST THROUGH THE WEST
COAST AND GREAT BASIN REGION. WATER VAPOR IMAGERY ALSO INDICATING AN
EMBEDDED SHORT WAVE TRANSLATING ACROSS THE GREAT BASIN AT THIS TIME.
LATEST SFC OBSERVATIONS INDICATING A WELL MIXED ATMOSPHERE ACROSS
THE AREA WITH BREEZY TO WINDY SOUTHWEST WINDS...WARM TEMPERATURES IN
THE 70S TO LOWER 80S LOWER ELEVATIONS...50S AND 60S ACROSS THE
HIGHER TERRAIN...DEW PTS MAINLY IN THE SINGLE DIGITS ABOVE AND BELOW
ZERO...ALL LEADING TO DANGEROUS FIRE WEATHER CONDITIONS BEING
EXPERIENCED ACROSS ALL OF THE NON SNOW COVERED AREAS OF SOUTH CENTRAL
AND SOUTHEAST COLORADO.
HOWEVER...LOW LEVEL MOISTURE IS NOT TOO FAR AWAY WITH REGIONAL
RADARS INDICATING A FINE LINE FROM NEAR DIA TO BURLINGTON AND INTO
WEST CENTRAL KANSAS...WITH DEW PTS IN THE 20S...30S AND 40S NORTH
AND EAST OF THE BOUNDARY INTO NORTHEASTERN COLORADO AND NORTHWESTERN
KANSAS.
TONIGHT AND TOMORROW...MODERATE TO STRONG SW FLOW ALOFT PROGGED TO
CONTINUE ACROSS THE AREA THROUGH THE PERIOD WITH GREAT BASIN
EMBEDDED WAVE CONTINUING TO TRANSLATE NORTH AND EAST ACROSS THE
NORTHERN ROCKIES TONIGHT AND ANOTHER SHORT WAVE PROGGED TO MOVE INTO
THE GREAT BASIN REGION THROUGH THE DAY TOMORROW. FIRST WAVE LOOKS TO
HELP PUSH LOW LEVEL MOISTURE GRADIENT/FRONT SOUTH AND WEST ACROSS
PORTIONS OF THE PALMER DVD AND NORTHERN PORTIONS OF THE SE PLAINS
TONIGHT WITH THE HRRR THE MOST AGGRESSIVE PUSHING MID 40 DEW PTS AND
STRATUS WELL INTO KIOWA AND PROWERS COUNTIES OVERNIGHT...WHICH MAY
BE A TAD OVERDONE. FURTHER WEST...WILL LIKELY SEE POOR RH RECOVERY
WITH LOWS SIMILAR TO LAST NIGHTS.
THIS BOUNDARY LOOKS TO MIX OUT THROUGH THE LATE MORNING AND EARLY
AFTERNOON TOMORROW AS LEE TROUGH STRENGTHENS ACROSS THE EASTERN
PLAINS AHEAD OF THE NEXT EMBEDDED SHORT WAVE. THIS ALL POINTS TO
ANOTHER DAY OF HIGH FIRE DANGER...ESPECIALLY FOR AREAS ALONG THE I-
25 CORRIDOR AND BACK WEST ACROSS THE REST OF THE EASTERN MTS TO THE
CONTDVD. WITH THAT SAID...HAVE UPGRADED AND EXPANDED A RED FLAG
WARNING FOR TOMORROW FROM NOON TO 8 PM FOR ALL OF THE NON SNOW
COVERED MTS...THE HIGH MT VALLEY AND THROUGH THE I-25 CORRIDOR. I
DID NOT INCLUDE THE FAR SE PLAINS WITH MARGINAL WINDS...THOUGH IF
DEEP ENOUGH MIXING CAN OCCUR...COULD SEE RED FLAG CONDITIONS THERE
AS WELL.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 245 PM MDT MON APR 6 2015
...DRY AND WINDY WEATHER CONTINUES...
A SERIES OF PROGRESSIVE TROUGHS WILL IMPACT OUR AREA OVER THE NEXT
SIX TO TEN DAYS...UNFORTUNATELY NONE OF THEM LOOK VERY ORGANIZED AND
IT LOOKS LIKE THERE WILL BE MORE WIND THAN PRECIPITATION FROM THIS
PATTERN. THE ONLY OPTIMISTIC THING THAT CAN BE SAID IS THAT THE
MODELS ARE STRUGGLING WITH THE PATTERN...SO THERE IS TIME FOR IT TO
CHANGE.
WEDNESDAY STILL LOOKS LIKE A DAY OF POTENTIALLY EXTREME FIRE
WEATHER. WITH INCREASING WRLY FLOW ALOFT...WILL SEE VERY LOW RH OVER
MOST OF THE AREA...AND ANOTHER ROUND OF STRONG-GUSTY WINDS IN THE
AFTERNOON AND EARLY EVE. HAVE HOISTED A FIRE WX WATCH FOR MOST OF
THE CWA. ONLY AREAS THAT MIGHT ESCAPE ARE THE PIKES PEAK REGION AND
THE CENTRAL MTS. TEMPS ALOFT WILL BE FALLING...SO DEPENDING ON THE
SPEED OF THE COLD FRONT THE RH VALUES FOR THE NRN AND CENTRAL MTN
AREAS MAY BE HIGH ENOUGH TO PRECLUDE RED FLAG. BUT IT WILL BE
ANOTHER DAY OF HIGH FIRE DANGER FOR THE PLAINS. EXTREME NERN
CORNER...BASICALLY KIOWA COUNTY...WILL BE A BIT SLOWER TO MIX OUT
DUE TO SOME MORNING LOW CLOUDS...BUT BY MID TO LATE AFTERNOON MOST
OF THE PLAINS SHOULD BE ON THE BREEZY-WINDY SIDE.
MODELS ARE NOW ALL ON BOARD WITH A MORE NORTHERLY TRACK FOR THE LATE
WED-THU SYSTEM. AS EXPECTED...THE OUTLIER ECMWF HAS FALLEN INTO LINE
WITH THE GFS...AND THE NAM-GFS SOLUTION HAS COME TOGETHER WITH A LOW
THAT TRACKS THROUGH WY. SO...PRECIP CHANCES NOT LOOKING VERY GOOD
FOR US RIGHT NOW. STILL LOOKS LIKE THE PIKES PEAK REGION AND CENTRAL
MTS N OF HGWY 50 WILL GET SOME SNOW...PERHAPS A COUPLE INCHES. BUT
ELSEWHERE...HAVE TRIMMED BACK THE LOW POPS AND WILL KEEP THEM SILENT
FOR NOW. TEMPS OVER THE PLAINS ON THU SHOULD BE MAINLY IN THE UPPER
50S-LOWER 60S.
RIDGING ON FRIDAY SHOULD MITIGATE FIRE WX CONCERNS...AS WINDS DIE
DOWN FOR A DAY OR SO. BUT IT STILL LOOKS DRY...AS DOES SATURDAY WHEN
SWRLY FLOW PICKS UP ONCE AGAIN AND LEADS TO MORE FIRE WX CONCERNS.
NEXT SYSTEM IS STILL BEING HANDLED QUITE DIFFERENTLY BY THE GLOBAL
MODELS. MODELS ARE ALL SHOWING A SPLIT SYSTEM...BUT THE GFS HAS A
WEAKER CUTOFF...AND BROAD DISORGANIZED CUTOFF LOW OVER NRN CO AND WY
BY MONDAY. THE ECMWF HAS A MORE ZONAL PATTERN TO OUR NORTH...BUT
KEEPS THE SRN CUTOFF SYSTEM TOO FAR SOUTH TO IMPACT OUR AREA.
NEITHER 12Z SOLUTION WOULD BRING US MUCH PRECIPITATION...WE JUST CAN
NOT GET A BREAK FROM THIS DISORGANIZED PATTERN! STILL...IT LOOKS
LIKE A CONTINUED PERIOD OF UNSETTLED WEATHER WITH SHOWERS PROBABLE
FOR AT LEAST THE MTN AREAS. ROSE
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 245 PM MDT MON APR 6 2015
VFR CONDITIONS TO PREVAIL AT COS...PUB AND ALS OVER THE NEXT 24
HOURS. GUSTY SOUTHWEST WINDS 15-30KT EXPECTED THROUGH AT LEAST 02Z
TUE WITH SFC WINDS DIMINISHING THEREAFTER WITH LOSS OF SUN AND
MIXING. ALS TO SEE GUSTY SW WINDS AGAIN AFT 16Z TUE WITH A WEAK
FRONTAL BOUNDARY SLIDING ACROSS PORTIONS OF THE SE PLAINS POSSIBLY
DELAYING THE DEVELOPMENT OF GUSTY SW WINDS AT COS AND PUB UNTIL
18Z-21Z TUE.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY
EVENING FOR COZ222-224>237.
RED FLAG WARNING FROM NOON TO 8 PM MDT TUESDAY FOR COZ220>230-
233.
&&
$$
UPDATE...PETERSEN
SHORT TERM...MW
LONG TERM...ROSE
AVIATION...MW
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
756 PM MDT MON APR 6 2015
.UPDATE...
ISSUED AT 751 PM MDT MON APR 6 2015
LATEST DATA INDICATE AREAS OF LOW CLOUDS AND FOG WILL DEVELOP
TOWARDS MIDNIGHT OVER THE FAR NERN PLAINS AND THEN POSSIBLY
SPREAD WESTWARD INTO THE FRONT RANGE URBAN CORRIDOR BY 12Z BEHIND
WK COOL FNT. THERE IS SOME POTENTIAL FOR LOCALLY DENSE FOG LATE
TONIGHT THROUGH THE MID MORNING HOURS ON TUESDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 335 PM MDT MON APR 6 2015
SOUTHWEST FLOW ALOFT OVER THE REGION WITH A SURFACE LOW OVER THE
EASTERN PORTIONS OF THE STATE. A COLD FRONT HAS PUSHED THROUGH
FROM THE NE INTO CENTRAL NE PLAINS BRINGING INCREASED GUSTING TO
THE REGION BUT LITTLE IN THE WAY OF CLOUD COVER. WINDS WILL
CONTINUE TO DOWNSLOPE OFF THE PALMER DIVIDE AND CENTRAL FOOTHILLS
TO HELP INCREASE TEMPERATURES INTO THE LOW TO MID 70S. THIS
COMBINED WITH GUSTY WINDS UP TO 35 MPH AND DRY FUELS WITH INCREASE
FIRE DANGER OVER ZONES 241, 214, 246 AND 247 THROUGH THE
AFTERNOON. LATER THIS EVENING THE WINDS WILL DECREASE WITH RH
VALUES MOVING OUT OF RFW CRITERIA. CEILINGS WILL INCREASE OVER THE
MOUNTAINS OVERNIGHT WITH AN INCREASE IN MID LEVEL MOISTURE AHEAD
OF THE NEXT SYSTEM. MODEL CROSS SECTIONS ARE INDICATING SOME LOW
LEVEL CLOUDS/PATCHY FOG EAST OF I-25 NEAR DAWN.
FOR TOMORROW THE POST FRONTAL AIRMASS WILL BE IN PLACE DROPPING
DAYTIME TEMPERATURES 5-10 DEGREES INTO THE LOWER TO MID 60S OVER
THE REGION. MOISTURE INCREASES OVER THE MOUNTAINS AND NORTHERN
BORDER OF THE STATE WITH WARM SE WINDS RETURNING KEEPING COUNTIES
TO THE SOUTH A BIT DRIER. THIS WARM FLOW COMBINED WITH LOWERED RH
VALUES AND FUELS WILL INCREASE FIRE HAZARD CRITERIA ONCE AGAIN FOR
ZONES 246...247 AND 241.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 335 PM MDT MON APR 6 2015
MODELS WILL CONTINUE TO KEEP US GUESSING ON THE TRACK OF WEDNESDAY
AND THURSDAYS UPPER LOW UNTIL THE TROUGH ACTUALLY ARRIVES. MOST OF
THE SOLUTIONS CONTINUE TO FAVOR A MORE NORTHERN TRACK. BUT IF THE
LOW TRACKS 100 MILES SOUTH OF CONCENSUS...THERE ARE BIG
IMPLICATIONS ON HOW MUCH PRECIPITATION WILL FALL ACROSS NORTHEAST
COLORADO. THE FARTHER SOUTH THE LOW CENTER MAKES IT...THE MORE
PRECIPITATION THAT PLACES LIKE DENVER AND THE PALMER DIVIDE WILL
SEE. THE SYSTEM ITSELF LOOKS PRETTY STRONG AT THE PRESENT
TIME...JUST OFF THE COAST OF WASHINGTON AND OREGON. OPEN CELL
CUMULUS CLOUDS ON THE INFRARED IMAGERY INDICATE HOW MUCH COLD AIR
THE SYSTEM IS GOING TO BE BRINGING WITH IT. THIS WILL HELP TO DROP
SNOW LEVELS TO DROP TO 6000 FEET OR SO WEDNESDAY NIGHT AND
THURSDAY MORNING. MOUNTAIN AREAS MAY SEE SEVERAL INCHES OF NEW
SNOW DURING THE 24-36 HOURS THAT THE UPPER TROUGH IS OVER THE
STATE. PLAINS LOCATIONS WILL SEE EITHER RAIN OR A MIX OF RAIN AND
SNOW AT TIMES WITH HIGHS ON THE PLAINS STILL EXPECTED TO REACH
THE UPPER 40S THURSDAY AFTERNOON. THE UPPER TROUGH WILL BE
CLEARING OUT OF THE STATE THURSDAY NIGHT WITH DRIER AND WARMER
WEATHER EXPECTED TO RETURN ON FRIDAY. MOUNTAIN AREAS MAY STILL SEE
SCATTERED SNOW SHOWERS THROUGH FRIDAY AS MOIST NORTHWESTERLY FLOW
WILL BE CONTINUING.
AHEAD OF THE UPPER TROUGH...WEDNESDAY MAY END UP BEING A PARTLY-
MOSTLY CLOUDY DAY AS QUITE A BIT OF STRATUS IS EXPECTED TO MOVE IN
FROM THE CENTRAL PLAINS...BEHIND A SURFACE COLD FRONT THAT WILL
MOVE IN TUESDAY. THIS WILL KEEP WEDNESDAY AFTERNOON TEMPERATURES
AROUND THE SAME LEVEL WE SEE TUESDAY AFTERNOON.
FOR THE REST OF THE WEEKEND...THEIR IS MARGINAL CONFIDENCE TAHT
DRY AND WARM WEATHER WILL CONTINUE SATURDAY UNDER FLAT RIDGING
ALOFT. SUNDAY AND MONDAY COULD BE A CONTINUATION OF DRY WEATHER
AND SEASONAL TEMPERATURES...OR THEY COULD BE SHOWERY IF MOISTURE
ON THE PLAINS IS DRAWN WESTWARD AHEAD OF THE NEXT APPROACHING
UPPER TROUGH.
&&
.AVIATION...(FOR THE TAFS THROUGH 06Z TUESDAY EVENING)
ISSUED AT 751 PM MDT MON APR 6 2015
AS MENTIONED EARLIER THERE IS SOME POTENTIAL FOR LOW CLOUDS AND
FOG BY AROUND 12Z WHICH MAY LINGER THRU AT LEAST 15Z BEHIND WK
FNTL BNDRY. LATEST HRRR INDICATES THERE COULD BE SOME DENSE FOG
WITH VISIBILITIES UNDER ONE HALF MILE WHICH MAY AFFECT DIA FOR A
FEW HOURS.
&&
.FIRE WEATHER...
ISSUED AT 335 PM MDT MON APR 6 2015
WARM SW WINDS COMBINED WITH LOWERED DEWPOINTS AND DRY FUELS WILL
KEEP FIRE WEATHER CONDITIONS CRITICAL FOR THIS AFTERNOON AS WELL
AS TOMORROW AFTERNOON. ZONES 214...241..246 AND 247 WILL REMAIN IN
THE WARNING UNTIL 6 PM THIS EVENING. ANOTHER CHANCE TO HIT RED
FLAG CRITERIA WILL BE TOMORROW AFTERNOON AS RH VALUES DROP TO THE
LOWER TEENS OVER PORTIONS OF LINCOLN, ELBERT AND EASTERN DOUGLAS
COUNTIES. A FIRE WEATHER WATCH HAS BEEN ISSUED FOR THESE AREAS FOR
TOMORROW FROM NOON UNTIL 6 PM WITH THE MOST CRITICAL TIME BEING IN
THE LATE AFTERNOON AS WINDS AND RH VALUES REACH PEAK CRITERIA DUE
TO BEST MIXING.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH TUESDAY AFTERNOON FOR COZ241-246-247.
&&
$$
UPDATE...RPK
SHORT TERM...BOWEN
LONG TERM...DANKERS
AVIATION...RPK
FIRE WEATHER...BOWEN
AREA FORECAST DISCUSSION
NWS ALBANY NY
108 AM EDT SUN APR 5 2015
.SYNOPSIS...
HIGH PRESSURE WILL CREST OVER THE REGION OVERNIGHT. IT WILL
BE CHILLY WITH LOWS IN THE TEENS AND 20S. OUR WEATHER WILL TURN
UNSETTLED SUNDAY AFTERNOON INTO MID WEEK AS A FRONTAL BOUNDARY
DRIFTS BETWEEN THE I-90 AND I-70 CORRIDOR. IT WILL RESULT IN
LIGHT RAIN AND SNOW ACROSS THE LOCAL AREA.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1150 PM EDT...CLOUDS HAVE INCREASED ACROSS MUCH OF THE
REGION EXCEPT ACROSS THE MID HUDSON VALLEY AND NW CT...AHEAD OF A
COMPACT YET FAIRLY POTENT SHORTWAVE ACROSS FAR WESTERN NYS.
REGIONAL RADARS INDICATE SOME BANDS OF SNOW SHOWERS CURRENTLY
ONGOING ACROSS SW NYS...SOME LOCALLY HEAVY...WITH LIGHTER SNOW
SHOWERS EXTENDING FURTHER N AND E INTO THE WESTERN MOHAWK VALLEY
AND ADIRONDACKS.
HIGHER RES MODELS SUCH AS THE RAP13 AND HRRR SUGGEST THAT AT LEAST
SCATTERED SNOW SHOWERS DEVELOP ACROSS THE EASTERN CATSKILLS
BETWEEN 2 AND 4 AM...WITH ISOLATED SNOW SHOWERS POSSIBLY EXTENDING
AS FAR N AND E AS THE CAPITAL REGION...BERKSHIRES...AND AS FAR S
AND E AS THE LITCHFIELD HILLS...SOUTHERN TACONICS...AND MID HUDSON
VALLEY DURING THIS TIME FRAME. ADDITIONAL SNOW SHOWERS SHOULD
OCCUR ACROSS THE WESTERN ADIRONDACKS AND MOHAWK VALLEY. THE BEST
CHANCE FOR SOME MINOR ACCUMS OVERNIGHT WILL BE ACROSS THE EASTERN
CATSKILLS...WHERE A FEW BURSTS OF MODERATE SNOW COULD
OCCUR...LEADING TO ACCUMS OF UP TO AN INCH. ELSEWHERE...MOST
ACCUMS THROUGH DAYBREAK SHOULD RANGE FROM A DUSTING ON COLDER
SURFACES IN LOWER ELEVATIONS...TO AROUND ONE HALF OF AN INCH
ACROSS HIGHER ELEVATIONS.
THE COMBINATION OF CLOUDS...AND SOME WIND...SHOULD PREVENT TEMPS
FROM GETTING VERY COLD OVERNIGHT. HAVE RAISED OVERNIGHT MINS BY A
FEW TO SEVERAL DEGREES...WITH MAINLY 20S EXPECTED...EXCEPT PERHAPS
ONLY FALLING TO AROUND 30 IN PORTIONS OF THE MID HUDSON
VALLEY...AND POSSIBLY SOME UPPER TEENS ACROSS HIGHER ELEVATIONS
ACROSS THE WESTERN ADIRONDACKS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
TURNING UNSETTLED.
A WEAK LOW PRESSURE SYSTEM WILL MOVE INTO THE REGION ON SUNDAY AS
THE FLOW ALOFT BECOMES ZONAL. THIS WILL CAUSE THE SYTSEM`S COLD
FRONT TO STALL ACROSS THE REGION...ACROSS THE MID/LOWER HUDSON
VALLEY AND SOUTHERN NEW ENGLAND. THE BOUNDARY WILL BE THE FOCUS
FOR LIGHT PRECIPITATION INTO EARLY NEXT WEEK WITH IT SHIFTING
NORTHWARD ON MONDAY.
CHANCES FOR PRECIPITATION WILL INCREASE SUNDAY AFTERNOON THEN
PERSIST THROUGH MONDAY NIGHT. INITIALLY THE FOCUS WILL BE THE
SOUTHERN PORTION OF THE FORECAST AREA...THEN SHIFTING NORTHWARD.
IT WILL BE COLD ENOUGH FOR SNOW...HOWEVER THE BOUNDARY LAYER WILL
BE WARM ENOUGH FOR MAINLY RAIN DURING THE DAYTIME. QPF AMOUNTS
WILL BE VERY LIGHT WITH ONLY UP TO QUARTER INCH POSSIBLE THROUGH
MONDAY NIGHT. SNOW ACCUMULATIONS WILL BE LIGHT...AT THIS TIME IT
APPEARS UP TO AN INCH OR TWO IS POSSIBLE ACROSS PORTIONS OF THE
ADIRONDACKS AND SOUTHERN VERMONT SUNDAY INTO MONDAY.
SUNDAY WILL FEATURE MORE BELOW NORMAL TEMPERATURES WITH MORE
SEASONABLE READINGS MONDAY AS THE BOUNDARY SHIFTS NORTHWARD.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE SAGA OF THE WAVERING BAROCLINIC ZONE OVER/AROUND OUR REGION WILL
CONTINUE AS CONFLUENT UPPER WESTERLY FLOW DOMINATES AND FLAT UPPER
RIDGING JUST SO GRADUALLY AMPLIFIES...ALLOWING THE LOW LEVEL
BAROCLINIC ZONE TO JUST SO SLOWLY DRIFT NORTHWARD TUESDAY. THEN SOME
QUICK SMALL NORTHERN STREAM UPPER ENERGY ENHANCES THE UPPER
CONFLUENCE IN EASTERN CANADA AND THE NORTHEASTERN U.S. RESULTING IN
NORTHERN STREAM BASED LOW LEVEL RIDGING...PUSHING THE BAROCLINIC
ZONE A LITTLE SOUTH...COOLING OUR REGION A LITTLE...ESPECIALLY
WEDNESDAY INTO THURSDAY. THEN...AS A STRONG UPPER IMPULSE TRACKS
INTO THE CENTRAL PART OF THE U.S. AND UPPER TROUGHING LIFTS OUT OF
EASTERN CANADA THURSDAY THROUGH SATURDAY...BETTER UPPER RIDGING IN
EASTERN NORTH AMERICA AND POTENTIALLY MORE LOW LEVEL WARMING AS THE
BAROCLINIC ZONE DRIFTS NORTH AGAIN.
SO...TIMING PIECES OF UPPER ENERGY AND QUICK SHOTS OF LOW LEVEL
FORCING ALONG THE LOW LEVEL BAROCLINIC ZONE AND ASSOCIATED
PRECIPITATION PROVIDES SOME CHALLENGES. BASED ON THE LATEST
GUIDANCE...WHICH IS SUBJECT TO CHANGE WITH SUCCESSIVE SETS OF
GUIDANCE INTO THE BEGINNING OF NEXT WEEK AS ATMOSPHERIC FEATURES
BECOME BETTER RESOLVED...PUTTING ENHANCED CHANCES FOR LIGHT RAIN AND
SNOW FOR TUESDAY AND TUESDAY NIGHT...TAPERING OFF WEDNESDAY. HIGHS
TUESDAY IN THE 40S IN MOST AREAS...BUT PERHAPS MID 50S SOUTHERN
AREAS...DEPENDING ON WHERE THE BAROCLINIC ZONE SETS UP. HIGHS
WEDNESDAY AROUND 5 DEGREES COOLER THAN TUESDAY AS THE COOLING TAKES
PLACE.
THERE SHOULD BE A PERIOD OF ISOLATED RAIN/SNOW SHOWER COVERAGE
WEDNESDAY NIGHT AND THURSDAY WITH LITTLE TO NO ENHANCED LOW LEVEL
FORCING BUT THE BAROCLINIC ZONE SHOULD STILL BE OVER SOME PART OF
THE REGION. THEN ANOTHER PERIOD OF ENHANCED COVERAGE OF SHOWERS
THURSDAY NIGHT INTO SATURDAY AS THE WARM ADVECTION AND ISENTROPIC
LIFT GRADUALLY INCREASE AHEAD OF THE ADVANCING UPPER ENERGY IN THE
CENTRAL U.S. SUSPECT THERE WILL BE PERIODS OF DRY WEATHER IN THIS
TIME SPAN FROM THURSDAY NIGHT THROUGH SATURDAY...ESPECIALLY IN AREAS
SOUTH OF THE BAROCLINIC ZONE THAT BREAK INTO THE WARM SECTOR. BUT
AGAIN...TIMING VERY MUCH IN QUESTION SO BROAD BRUSHING CHANCES UNTIL
TIMING IS CLEARER AS WE GET TOWARD THE THE END OF NEXT WEEK.
HIGHS THURSDAY IN THE 40S TO LOWER 50S. HIGHS FRIDAY IN THE
50S...SOME UPPER 40S NORTH...AND HIGHS SATURDAY IN THE 50S TO AROUND
60. AGAIN...TEMPERATURES SUBJECT TO CHANGE DEPENDING ON WHERE THE
TIGHT LOW LEVEL THERMAL GRADIENT SETS UP.
&&
.AVIATION /05Z SUNDAY THROUGH THURSDAY/...
MAINLY VFR CONDITIONS ARE EXPECTED AT THE TAF SITES THROUGH THE
END OF THE TAF PERIOD ENDING AT 06Z MONDAY. SKIES WILL MAINLY BE
SCT- BKN035-050 OVERNIGHT WITH SOME SCATTERED SNOW SHOWERS PSBL.
HAVE ACCOUNTED FOR THESE WITH A VCSH AS THERE IS SOME UNCERTAINTY
IF THEY WILL HOLD TOGETHER AS THEY MOST EAST AHEAD OF A SHORT WAVEPUSHING
ACRS SRN CANADA. FOR TODAY A BOUNDARY TO OUR SOUTH BEGINS TO DRIFT
NORTH AS A WARM FRONT. AOA BKN-OVC080 CLOUDS WILL OVER SPREAD THE
AREA WITH INCRG SCT-BKN040-050 DURING THE AFTN. ISOLD TO SCT
-SHRA/SNSH MAY DVLP DURING THE AFTN...BUT ATTM TOO SPARSE TO
INCLUDE IN TAFS.
NORTHWEST WINDS WILL DIMINISH TO 10 KT OR LESS TONIGHT. WINDS
WILL SHIFT TO WEST BY DAYBREAK AND INCREASE TO 10 TO 15 KT THIS
MORNING.
OUTLOOK...
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF RA.
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF RA.
TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. LIKELY RA...SN.
WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN.
WEDNESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF RA...SN.
THURSDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF RA.
&&
.FIRE WEATHER...
BRISK AND GUSTY WESTERLY WINDS WILL WEAKEN TONIGHT AS HIGHER
PRESSURE BUILDS IN. THE WEATHER WILL TURN UNSETTLED BEGINNING
SUNDAY AFTERNOON AND IS EXPECTED TO PERSIST THROUGH EARLY NEXT
WEEK.
&&
.HYDROLOGY...
THE ONLY FLOOD WARNING IN EFFECT IS FOR THE MOHAWK RIVER AT UTICA
HARBOR FOR MINOR FLOODING. BASED ON THE CURRENT RIVER FORECASTS
THE ONLY RIVER POINT FORECAST TO REACH FLOOD STAGE IS ON THE
HOUSATONIC RIVER AT GAYLORDSVILLE AND THIS COULD FALL JUST SHY.
TEMPERATURES TONIGHT WILL TURN COLDER WITH TEENS AND 20S EXPECTED
ENDING SNOWMELT. THEN THERE WILL BE DIURNAL MELTING OF THE SNOW AS
WE HEAD INTO NEXT WEEK WITH TEMPERATURES AT NIGHT COLD ENOUGH TO
SNOW AND EVEN STOP THE MELT.
THE WEATHER WILL TURN UNSETTLED BEGINNING SUNDAY AFTERNOON AS A
FRONTAL BOUNDARY BECOMES STALLED ACROSS THE REGION AT LEAST
THROUGH EARLY NEXT WEEK. AT THIS TIME...EXPECTED QPF AMOUNTS
THROUGH MONDAY NIGHT ARE EXPECTED TO BE A QUARTER INCH OF LESS
WITH SOME OF THAT FALLING AS SNOW.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...IAA/SNYDER
NEAR TERM...IAA/KL/SNYDER
SHORT TERM...IAA
LONG TERM...NAS
AVIATION...11
FIRE WEATHER...IAA
HYDROLOGY...IAA
AREA FORECAST DISCUSSION
NWS MIAMI FL
830 PM EDT MON APR 6 2015
.UPDATE...
CONVERGENCE BETWEEN EASTERLIES AND THE GULF COAST SEA BREEZE,
ALONG WITH A VERY SUBTLE WAVE DROPPING SOUTHEAST FROM THE
NORTHEASTERN GULF, PROVIDED JUST ENOUGH LIFT FOR SHOWERS ALONG
INLAND COLLIER THIS EVENING, MUCH LESS THAN WHAT THE HRRR HAS
PREDICTED. THIS CLUSTER COULD MAKE IT TO PART OF NAPLES OVER THE
NEXT FEW HOURS WHILE WEAKENING. OTHERWISE, COASTAL CONVERGENCE,
MINIMAL DIRECTIONAL SHEAR THROUGH H7, AND EAST WINDS 10-15KT WILL
BE ENOUGH FOR AT LEAST SLT CHC POPS OFFSHORE AND ALONG THE ENTIRE
EAST COAST FOR THE REST OF TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 742 PM EDT MON APR 6 2015/
AVIATION...
ISOLATED SHOWERS REMAIN ACROSS THE ATLANTIC WATERS EARLY THIS
EVENING. AS EASTERLY FLOW PERSISTS THROUGH THE NIGHT...SOME OF
THESE SHOWERS COULD BRIEFLY AFFECT THE EAST COAST SITES BUT NOT
CONFIDENT ENOUGH TO MENTION IN TAFS. MAINLY DRY CONDITIONS
EXPECTED ON TUESDAY WITH EASTERLY FLOW PREVAILING.
PREV DISCUSSION... /ISSUED 237 PM EDT MON APR 6 2015/
SHORT TERM (TONIGHT-WEDNESDAY NIGHT)...
THE SHORT TERM PERIOD LOOKS RATHER SUBDUED AS A MID/UPPER LEVEL
RIDGE AXIS REMAINS ACROSS THE EASTERN GULF OF MEXICO. THIS RIDGE
WILL AMPLIFY LATE TUESDAY INTO WEDNESDAY IN RESPONSE TO A STRONG
TROUGH MOVING ONTO THE NORTHERN CALIFORNIA COAST AND INTO THE
CENTRAL ROCKIES. A SURFACE HIGH PRESSURE RIDGE CURRENTLY LOCATED
ACROSS THE SOUTHEAST STATES WILL ALSO MOVE LITTLE PROVIDING SOUTH
FLORIDA WITH A GENERAL LOW LEVEL EAST TO SOUTHEAST FLOW. FORECAST
SOUNDINGS SUGGEST THAT THIS PATTERN WILL BE FAVORABLE FOR A FEW
ATLANTIC SHOWERS TO MOVE ONSHORE ALONG THE SOUTHEAST COAST THROUGH
THIS PERIOD WITH A FEW AFTERNOON SHOWERS OVER THE INTERIOR AND WEST
COAST.
LONG TERM (THURSDAY-MONDAY)...
THE AMPLIFIED MID LEVEL RIDGE WILL CONTINUE THROUGH FRIDAY AND THEN
WEAKEN AND SHIFT BACK TO THE SOUTH OVER THE WEEKEND AS A POTENT
TROUGH MOVES THROUGH THE CENTRAL PLAINS. AS THIS PATTERN SHIFT
OCCURS, FORECAST SOUNDINGS SHOW SOME MOISTURE INCREASE WITH PWAT
CLIMBING TO AROUND 1.5" WHICH IS RUNNING ABOVE NORMAL FOR GOING INTO
THE MIDDLE OF APRIL. IN ADDITION, THERE WILL ALSO BE SOME
DESTABILIZATION OCCURRING AS 500MB TEMPERATURES COOL SLIGHTLY. THE
CENTRAL PLAINS TROUGH THEN LIFTS TO THE NORTHEAST EARLY NEXT WEEK
WITH THE RIDGE AMPLIFYING TO THE NORTH ONCE AGAIN.
MARINE...
AN EAST TO SOUTHEAST WIND WILL CONTINUE THROUGH THE PERIOD WITH
SEAS OF 2-4 FEET OVER THE ATLANTIC WATERS AND 1-2 FEET IN THE GULF
WATERS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 73 83 72 85 / 20 10 10 10
FORT LAUDERDALE 73 83 73 83 / 20 10 10 10
MIAMI 73 85 73 86 / 20 10 10 10
NAPLES 70 88 70 88 / 20 10 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...30/KOB
LONG TERM....30/KOB
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1042 PM EDT MON APR 6 2015
.SYNOPSIS...
HIGH PRESSURE TO OUR EAST WILL MAINTAIN SUFFICIENT ATMOSPHERIC
MOISTURE OVER OUR REGION THROUGH MUCH OF THIS WEEK. A FRONT WILL
MOVE THROUGH LATE FRIDAY AND EARLY SATURDAY AND PUSH TO OUR SOUTH BY
LATE SATURDAY INTO SUNDAY. THESE FACTORS...DAYTIME HEATING...AND
SOME UPPER ENERGY...WILL PROVIDE A CHANCE OF SHOWERS AND POSSIBLE
THUNDERSTORMS AT TIMES THIS WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
ZONAL UPPER LEVEL FLOW WILL CONTINUE OVER THE SERN STATES THROUGH
TONIGHT. AT 01Z RADAR INDICATED SHOWERS OVER NORTH GEORGIA AND
UPSTATE SOUTH CAROLINA ASSOCIATED WITH SHORT WAVE TROUGHS
APPROACHING FROM THE LOWER TENNESSEE VALLEY AND GULF COAST REGION.
ISENTROPIC LIFT/MOISTURE FLUX WILL BE INCREASING DURING THE NEXT
FEW HOURS ACROSS THE WEST MIDLANDS/CSRA...AIR MASS DRIER ACROSS
THE EAST MIDLANDS. RADAR TRENDS SUGGEST WEAKENING TREND AS THE
SHOWERS MOVE TOWARD THE REGION. THIS IS SUPPORTED BY LATEST HRRR
RUN. HOWEVER GIVEN INCREASING LIFT ASSOCIATED WITH SHORT WAVE WILL
INCREASE POPS IN THE WEST AND NORTH THROUGH 09Z. SHOWERS MAY MOVE
INTO THE EAST MIDLANDS LATE TONIGHT..BUT SHOULD BE WEAKENING. QPF
APPEARS LIGHT. LOWS TONIGHT WILL BE IN THE LOWER 60S WITH A LIGHT
SOUTH TO SOUTHEAST WIND.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
WEAK UPPER TROUGH AXIS WILL REMAIN NEAR THE WEST COAST...WHILE A
FLAT UPPER RIDGE REMAINS OVER THE GULF OF MEXICO AND GULF COAST. AN
EMBEDDED UPPER DISTURBANCE WILL TRACK EAST ACROSS OUR REGION TUESDAY.
SURFACE HIGH PRESSURE WILL PUSH A LITTLE FARTHER TO THE SE
OFFSHORE...AND DIRECT HIGHER MOISTURE INTO OUR REGION. ABOVE FACTORS
PLUS DIURNAL HEATING AND ANY CONVERGENCE ALONG SURFACE TROUGH OR SEA
BREEZE EXPECTED TO RESULT IN SCATTERED SHOWERS. SLIGHT CHANCE
THUNDER POSSIBLE AS WELL DUE TO INDICATIONS OF WEAK TO MODERATE
INSTABILITY.
WEAK UPPER RIDGE AXIS TO SHIFT OVERHEAD WEDNESDAY BEHIND DEPARTING
UPPER ENERGY...AND ATMOSPHERE APPEARS WILL BE A LITTLE LESS MOIST
WED AS WELL. THESE FACTORS SUGGEST LOWER POPS FOR WED.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
UPPER TROUGH TO SHIFT EAST FROM THE NORTHERN AND CENTRAL ROCKIES
ACROSS THE NORTHERN AND CENTRAL PLAINS...AND EVENTUALLY INTO THE
GREAT LAKES AND NEW ENGLAND REGION THROUGH THE PERIOD. WEAK UPPER
RIDGE OVER THE GULF OF MEXICO WILL WEAKEN AND SHIFT EAST ACROSS
FLORIDA AND INTO THE WESTERN ATLANTIC. FOR OUR REGION...THIS WILL
GENERALLY TRANSLATE INTO A GENERAL WSW UPPER FLOW WITH A SERIES OF
UPPER DISTURBANCES TRACKING ACROSS. AT THE SURFACE...A MOIST
GENERALLY S TO SW LOW LEVEL FLOW EXPECTED TO CONTINUE. THIS ALONG
WITH DIURNAL HEATING EXPECTED TO RESULT IN SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS. A COLD FRONT WILL APPROACH LATE FRIDAY...AND
APPEARS WILL SLOWLY ROLL THROUGH...DUE TO WSW TO SW FLOW
ALOFT...FRIDAY NIGHT AND SATURDAY MORNING TIME FRAME. APPEARS BEST
CHANCE OF SHOWERS AND THUNDERSTORMS WOULD BE ASSOCIATED WITH THE
FROPA DURING THIS TIME. GFS AND ECMWF INDICATE THE FRONT WILL SHIFT
TO OUR SOUTH BY LATE SAT AND SUNDAY. UNCERTAINTIES REMAIN WITH
TIMING OF FROPA AND CONFIDENCE REGARDING HOW FAR TO OUR SOUTH IT
WILL PUSH SUNDAY...WITH MOISTURE RETURN BACK INTO OUR AREA POSSIBLE
MONDAY.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS FOR MUCH OF THE PERIOD...EXCEPT POSSIBLE MVFR
CIGS AND VSBYS DURING THE PREDAWN HOURS TUESDAY MORNING AND
CONTINUING UNTIL AROUND 15Z.
AT THE SURFACE...HIGH PRESSURE IS OFF THE SOUTHEAST COAST BRINGING
AN ONSHORE FLOW WITH MOISTURE INCREASING THROUGH THE TAF PERIOD. AT
UPPER LEVELS THE FLOW IS ZONAL WITH ONE SHORTWAVE OVER MS/AL AND
ANOTHER SHORTWAVE OVER THE ARKLATEX REGION. THE FIRST SHORTWAVE WILL
MOVE OVER THE AREA LATER THIS EVENING BRINGING A CHANCE FOR SHOWERS
MAINLY AROUND MIDNIGHT ACCORDING TO LATEST HRRR RUN. WILL COVER WITH
-SHRA IN A TEMPO GROUP FOR ALL TAF SITES EXCEPT OGB. THE NEXT
SHORTWAVE WILL APPROACH DURING THE PREDAWN HOURS TUESDAY BRINGING AN
ANOTHER CHANCE OF SHOWERS...ESPECIALLY AROUND SUNRISE. WILL MENTION
VCSH AT ALL TAF SITES 09Z-15Z AS CONFIDENCE IS LOW CONCERNING
PRECIPITATION COVERAGE AND TIMING AFTER THAT TIME PERIOD. SFC WINDS
WILL BE MAINLY E TO SE OVERNIGHT BECOMING VARIABLE AFTER SUNRISE
TUESDAY. WIND SPEEDS WILL BE GENERALLY LESS THAN 10 KNOTS THROUGH
THE TAF PERIOD.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE TUESDAY NIGHT
THROUGH WEDNESDAY AS A FRONTAL BOUNDARY STALLS ACROSS THE REGION.
MOIST PATTERN CONTINUES FOR THURSDAY AND FRIDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
946 PM EDT MON APR 6 2015
.UPDATE...
FIRST WAVE OF SHOWERS CURRENTLY MOVING INTO NE GA. A SECOND
WAVE...ASSOCIATED WITH ANOTHER SHORTWAVE OVER WESTERN AL...IS
EXPECTED TO MOVE THROUGH THE AREA THROUGH THE EARLY MORNING HOURS.
NEWER RUNS OF THE HRRR HOLD THE SECOND AREA OF SHOWERS TOGETHER AS
IT MOVES ACROSS GA. WILL GO AHEAD AND KEEP THE SLIGHT CHANCE OF
THUNDER IN THE FORECAST...BUT INSTABILITY REMAINS WEAK.
&&
.PREV DISCUSSION... /ISSUED 736 PM EDT MON APR 6 2015/
PREV DISCUSSION... /ISSUED 349 PM EDT MON APR 6 2015/
SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
A MOIST SOUTHERLY LOW LEVEL FLOW WILL CONTINUE OVER NORTH AND CENTRAL
GA THROUGH THE FORECAST PERIOD ALONG WITH A NEAR ZONAL FLOW ALOFT.
UPPER LEVEL DISTURBANCES OVER WEST TN AND SOUTH LA WILL MOVE EAST
DURING THE NEXT 24 HOURS. THESE SYNOPTIC FEATURES WILL COMBINE WITH
A WARM FRONT OVER THE GULF COAST GRADUALLY MOVING NORTH THROUGH THE
STATE TONIGHT. CONSEQUENTLY...SCATTERED SHOWERS AND THUNDERSTORMS
WILL PREVAIL LATE THIS AFTERNOON AND TONIGHT WITH RAINFALL AMOUNTS
FROM 0.25 TO 0.50 INCH. DO NOT EXPECT ANY SEVERE TSTMS WITH THE
MARGINAL INSTABILITY.
ANOTHER SHORT WAVE WILL BE PASSING OVER THE TN VALLEY ON TUESDAY
WITH THE BEST CHANCES OF TSTMS OVER EXTREME NORTH GA. HOWEVER...
DIURNAL HEATING IN THE UPPER 70S AND 80S WITH A MOIST SOUTHWEST
FLOW WILL TRIGGER SCATTERED TSTMS OVER THE REMAINDER OF NORTH AND
ALL OF CENTRAL GA. THE SHOWERS AND TSTMS WILL GRADUALLY DIMINISH
ON TUESDAY EVENING.
THE WARM AND MOIST GULF FLOW WITH THE EXPECTED CLOUD COVER WILL
HOLD MIN TEMPS TO AROUND 10 DEGREES ABOVE NORMAL TONIGHT AND TUESDAY
NIGHT. MAX TEMPS ON TUESDAY WILL BE FROM 5 TO 10 DEGREES ABOVE
NORMAL AS WELL. ACCEPTED AND MERGED MET/MAV MOS GUIDANCE FOR POPS
AND TEMPS.
16
LONG TERM /WEDNESDAY THROUGH MONDAY/...
NO MAJOR CHANGES MADE TO THE EXTENDED FORECAST. WEST TO SOUTHWEST
UPPER FLOW CONTINUING OVER THE FORECAST AREA THROUGH THE PERIOD.
SEVERAL WEAK IMPULSES CROSS THE STATE RESULTING IN A GENERALLY
UNSETTLED PATTERN. HAVE CONTINUED WITH A CHANCE OR SLIGHT CHANCE
OF SHOWERS AND THUNDERSTORMS EACH DAY MOST AREAS. THE MOST
SIGNIFICANT SYSTEM SHOULD BE THE FRONT IN THE FRIDAY NIGHT THROUGH
SATURDAY PERIOD. SOME LIKELY POPS SEEM REASONABLE ALONG THE FRONT
FRIDAY. SOME DRYING INDICATED BEHIND THE FRONT FOR SATURDAY INTO
SUNDAY. HOWEVER...WITH SOME TIMING DIFFERENCES POSSIBLE FOR THAT
FAR OUT...HAVE LEFT IN A SLIGHT CHANCE OF SHOWERS OR THUNDERSTORMS
FOR THOSE TIMES. TEMPERATURES SHOULD BE WARM THROUGH THE
WEEK...EXCEPT COOLING SOME FOR THE WEEKEND.
41/01
AVIATION...
18Z UPDATE...
VFR CEILINGS GENERALLY PREVAILED OVER NORTH AND CENTRAL GA
WITH SCATTERED SHOWERS AND TSTMS APPROACHING FROM THE WEST IN AL.
EXPECT THE SHOWERS AND TSTMS TO INCREASE OVER THE TAF SITES
THROUGH THE REMAINDER OF THE AFTERNOON AND EVENING AS A WARM
FRONT MOVES NORTH THROUGH THE STATE TONIGHT. CEILINGS WILL
GRADUALLY LOWER TO IFR/MVFR AFTER MIDNIGHT THROUGH TUESDAY
MORNING. SURFACE WINDS WILL BE SOUTHEAST BECOMING SOUTHWEST ON
TUESDAY LESS THAN 10 KTS.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE FOR CEILINGS...VSBYS AND PRECIP TIMING.
HIGH CONFIDENCE FOR WINDS.
16
AVIATION...
00Z UPDATE...
WIDESPREAD LIGHT TO OCCASIONALLY MODERATE RAINFALL CONTINUES TO
OVERSPREAD THE AREA THIS EVENING. RAIN SHOULD TAPER OFF AROUND
MIDNIGHT...WITH IFR CIGS MAKING AN APPEARANCE. CIGS SHOULD IMPROVE
TO VFR BY LATE MORNING. WINDS MAY BRIEFLY SWITCH TO THE SW EARLY
IN THE PERIOD...BUT SE FLOW IS EXPECTED FOR THE REMAINDER OF THE
OVERNIGHT AND MOST OF TOMORROW. WINDS WILL TRY AND GO WEST OF
SOUTH LATE IN THE TAF PERIOD.
//ATL CONFIDENCE...00Z UPDATE...
MEDIUM CONFIDENCE ALL ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 69 59 78 60 / 80 90 40 30
ATLANTA 70 61 77 63 / 80 90 30 20
BLAIRSVILLE 57 55 73 54 / 80 80 50 20
CARTERSVILLE 71 59 77 59 / 80 90 40 10
COLUMBUS 77 62 82 65 / 70 80 20 10
GAINESVILLE 59 57 74 61 / 80 80 40 20
MACON 76 60 82 61 / 60 70 30 20
ROME 71 58 79 58 / 80 80 50 10
PEACHTREE CITY 73 59 78 57 / 80 90 30 20
VIDALIA 79 63 82 64 / 40 50 40 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...
AVIATION...
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
916 PM EDT MON APR 6 2015
.SYNOPSIS...
HIGH PRESSURE TO OUR EAST WILL MAINTAIN SUFFICIENT ATMOSPHERIC
MOISTURE OVER OUR REGION THROUGH MUCH OF THIS WEEK. A FRONT WILL
MOVE THROUGH LATE FRIDAY AND EARLY SATURDAY AND PUSH TO OUR SOUTH BY
LATE SATURDAY INTO SUNDAY. THESE FACTORS...DAYTIME HEATING...AND
SOME UPPER ENERGY...WILL PROVIDE A CHANCE OF SHOWERS AND POSSIBLE
THUNDERSTORMS AT TIMES THIS WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
ZONAL UPPER LEVEL FLOW WILL CONTINUE OVER THE SERN STATES THROUGH
TONIGHT. AT 01Z RADAR INDICATED SHOWERS OVER NORTH GEORGIA AND
UPSTATE SOUTH CAROLINA ASSOCIATED WITH SHORT WAVE TROUGHS
APPROACHING FROM THE LOWER TENNESSEE VALLEY AND GULF COAST REGION.
ISENTROPIC LIFT/MOISTURE FLUX WILL BE INCREASING DURING THE NEXT
FEW HOURS ACROSS THE WEST MIDLANDS/CSRA...AIR MASS DRIER ACROSS
THE EAST MIDLANDS. RADAR TRENDS SUGGEST WEAKENING TREND AS THE
SHOWERS MOVE TOWARD THE REGION. THIS IS SUPPORTED BY LATEST HRRR
RUN. HOWEVER GIVEN INCREASING LIFT ASSOCIATED WITH SHORT WAVE WILL
INCREASE POPS IN THE WEST AND NORTH THROUGH 09Z. SHOWERS MAY MOVE
INTO THE EAST MIDLANDS LATE TONIGHT..BUT SHOULD BE WEAKENING. QPF
APPEARS LIGHT. LOWS TONIGHT WILL BE IN THE LOWER 60S WITH A LIGHT
SOUTH TO SOUTHEAST WIND.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
WEAK UPPER TROUGH AXIS WILL REMAIN NEAR THE WEST COAST...WHILE A
FLAT UPPER RIDGE REMAINS OVER THE GULF OF MEXICO AND GULF COAST. AN
EMBEDDED UPPER DISTURBANCE WILL TRACK EAST ACROSS OUR REGION TUESDAY.
SURFACE HIGH PRESSURE WILL PUSH A LITTLE FARTHER TO THE SE
OFFSHORE...AND DIRECT HIGHER MOISTURE INTO OUR REGION. ABOVE FACTORS
PLUS DIURNAL HEATING AND ANY CONVERGENCE ALONG SURFACE TROUGH OR SEA
BREEZE EXPECTED TO RESULT IN SCATTERED SHOWERS. SLIGHT CHANCE
THUNDER POSSIBLE AS WELL DUE TO INDICATIONS OF WEAK TO MODERATE
INSTABILITY.
WEAK UPPER RIDGE AXIS TO SHIFT OVERHEAD WEDNESDAY BEHIND DEPARTING
UPPER ENERGY...AND ATMOSPHERE APPEARS WILL BE A LITTLE LESS MOIST
WED AS WELL. THESE FACTORS SUGGEST LOWER POPS FOR WED.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
UPPER TROUGH TO SHIFT EAST FROM THE NORTHERN AND CENTRAL ROCKIES
ACROSS THE NORTHERN AND CENTRAL PLAINS...AND EVENTUALLY INTO THE
GREAT LAKES AND NEW ENGLAND REGION THROUGH THE PERIOD. WEAK UPPER
RIDGE OVER THE GULF OF MEXICO WILL WEAKEN AND SHIFT EAST ACROSS
FLORIDA AND INTO THE WESTERN ATLANTIC. FOR OUR REGION...THIS WILL
GENERALLY TRANSLATE INTO A GENERAL WSW UPPER FLOW WITH A SERIES OF
UPPER DISTURBANCES TRACKING ACROSS. AT THE SURFACE...A MOIST
GENERALLY S TO SW LOW LEVEL FLOW EXPECTED TO CONTINUE. THIS ALONG
WITH DIURNAL HEATING EXPECTED TO RESULT IN SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS. A COLD FRONT WILL APPROACH LATE FRIDAY...AND
APPEARS WILL SLOWLY ROLL THROUGH...DUE TO WSW TO SW FLOW
ALOFT...FRIDAY NIGHT AND SATURDAY MORNING TIME FRAME. APPEARS BEST
CHANCE OF SHOWERS AND THUNDERSTORMS WOULD BE ASSOCIATED WITH THE
FROPA DURING THIS TIME. GFS AND ECMWF INDICATE THE FRONT WILL SHIFT
TO OUR SOUTH BY LATE SAT AND SUNDAY. UNCERTAINTIES REMAIN WITH
TIMING OF FROPA AND CONFIDENCE REGARDING HOW FAR TO OUR SOUTH IT
WILL PUSH SUNDAY...WITH MOISTURE RETURN BACK INTO OUR AREA POSSIBLE
MONDAY.
&&
.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS FOR MUCH OF THE PERIOD...EXCEPT POSSIBLE MVFR
CIGS AND VSBYS DURING THE PREDAWN HOURS TUESDAY MORNING AND
CONTINUING UNTIL AROUND 15Z.
AT THE SURFACE...HIGH PRESSURE IS OFF THE SOUTHEAST COAST BRINGING
AN ONSHORE FLOW WITH MOISTURE INCREASING THROUGH THE TAF PERIOD. AT
UPPER LEVELS THE FLOW IS ZONAL WITH ONE SHORTWAVE OVER MS/AL AND
ANOTHER SHORTWAVE OVER THE ARKLATEX REGION. THE FIRST SHORTWAVE WILL
MOVE OVER THE AREA LATER THIS EVENING BRINGING A CHANCE FOR SHOWERS
MAINLY AROUND MIDNIGHT ACCORDING TO LATEST HRRR RUN. WILL COVER WITH
-SHRA IN A TEMPO GROUP FOR ALL TAF SITES EXCEPT OGB. THE NEXT
SHORTWAVE WILL APPROACH DURING THE PREDAWN HOURS TUESDAY BRINGING AN
ANOTHER CHANCE OF SHOWERS...ESPECIALLY AROUND SUNRISE. WILL MENTION
VCSH AT ALL TAF SITES AFTER 10Z AS CONFIDENCE IS LOW CONCERNING
PRECIPITATION COVERAGE AND TIMING AFTER THAT TIME PERIOD. SFC WINDS
WILL BE MAINLY E TO SE OVERNIGHT BECOMING VARIABLE AFTER SUNRISE
TUESDAY. WIND SPEEDS WILL BE GENERALLY LESS THAN 10 KNOTS THROUGH
THE TAF PERIOD.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE TUESDAY NIGHT
THROUGH WEDNESDAY AS A FRONTAL BOUNDARY STALLS ACROSS THE REGION.
MOIST PATTERN CONTINUES FOR THURSDAY AND FRIDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
829 PM EDT MON APR 6 2015
.SYNOPSIS...
HIGH PRESSURE TO OUR EAST WILL MAINTAIN SUFFICIENT ATMOSPHERIC
MOISTURE OVER OUR REGION THROUGH MUCH OF THIS WEEK. A FRONT WILL
MOVE THROUGH LATE FRIDAY AND EARLY SATURDAY AND PUSH TO OUR SOUTH BY
LATE SATURDAY INTO SUNDAY. THESE FACTORS...DAYTIME HEATING...AND
SOME UPPER ENERGY...WILL PROVIDE A CHANCE OF SHOWERS AND POSSIBLE
THUNDERSTORMS AT TIMES THIS WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
ZONAL UPPER LEVEL FLOW WILL CONTINUE OVER THE SERN STATES THROUGH
TONIGHT. AT 18Z THERE IS AN AREA OF SHOWERS AND THUNDERSTORMS
ASSOCIATED WITH A SHORTWAVE EXTENDING FROM SOUTH CENTRAL KY SOUTH
ACROSS TENNESSEE AND CENTRAL AL. THIS SHORTWAVE WILL MOVE OVER
THE AREA LATER TONIGHT.
LATEST MESO-ANALYSIS...20Z...INDICATES WEAK INSTABILITY ACROSS
EAST CENTRAL GEORGIA WITH MID LEVEL CAPPING. AIR MASS OVER CENTRAL
MIDLANDS MORE STABLE WITH DRIER LOW LEVEL AIR. RADAR INDICATING
VERY LIGHT ISOLATED SHOWERS NEAR AGS...BUT NOTHING SIGNIFICANT.
LITTLE CHANGE EXPECTED FOR THE NEXT FEW HOURS INTO THE EARLY
EVENING AS SHORT WAVE REMAINS WEST OF AREA AND MID LEVEL CAP
PRESENT LIMITING CONVECTION.
THERE WILL BE WEAK INSTABILITY AS THE SHORTWAVE CROSSES THE AREA
LATE TONIGHT. WITH INCREASING MOISTURE THERE WILL BE A CHANCE OF
SHOWERS AND THE POSSIBILITY OF SOME THUNDER. MET POPS ARE MUCH
HIGHER OVERNIGHT THAN THE MAV POPS. WILL GO THE MIDDLE ROAD AND
AND KEEP POPS MAINLY IN THE 40 TO 50 PERCENT RANGE. BEST RAIN
CHANCES WILL BE AFTER MIDNIGHT. AFTER HIGHS THIS AFTERNOON IN THE
UPPER 70S...LOWS TONIGHT WILL BE IN THE LOWER 60S WITH A LIGHT
SOUTH TO SOUTHEAST WIND.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
WEAK UPPER TROUGH AXIS WILL REMAIN NEAR THE WEST COAST...WHILE A
FLAT UPPER RIDGE REMAINS OVER THE GULF OF MEXICO AND GULF COAST. AN
EMBEDDED UPPER DISTURBANCE WILL TRACK EAST ACROSS OUR REGION TUESDAY.
SURFACE HIGH PRESSURE WILL PUSH A LITTLE FARTHER TO THE SE
OFFSHORE...AND DIRECT HIGHER MOISTURE INTO OUR REGION. ABOVE FACTORS
PLUS DIURNAL HEATING AND ANY CONVERGENCE ALONG SURFACE TROUGH OR SEA
BREEZE EXPECTED TO RESULT IN SCATTERED SHOWERS. SLIGHT CHANCE
THUNDER POSSIBLE AS WELL DUE TO INDICATIONS OF WEAK TO MODERATE
INSTABILITY.
WEAK UPPER RIDGE AXIS TO SHIFT OVERHEAD WEDNESDAY BEHIND DEPARTING
UPPER ENERGY...AND ATMOSPHERE APPEARS WILL BE A LITTLE LESS MOIST
WED AS WELL. THESE FACTORS SUGGEST LOWER POPS FOR WED.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
UPPER TROUGH TO SHIFT EAST FROM THE NORTHERN AND CENTRAL ROCKIES
ACROSS THE NORTHERN AND CENTRAL PLAINS...AND EVENTUALLY INTO THE
GREAT LAKES AND NEW ENGLAND REGION THROUGH THE PERIOD. WEAK UPPER
RIDGE OVER THE GULF OF MEXICO WILL WEAKEN AND SHIFT EAST ACROSS
FLORIDA AND INTO THE WESTERN ATLANTIC. FOR OUR REGION...THIS WILL
GENERALLY TRANSLATE INTO A GENERAL WSW UPPER FLOW WITH A SERIES OF
UPPER DISTURBANCES TRACKING ACROSS. AT THE SURFACE...A MOIST
GENERALLY S TO SW LOW LEVEL FLOW EXPECTED TO CONTINUE. THIS ALONG
WITH DIURNAL HEATING EXPECTED TO RESULT IN SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS. A COLD FRONT WILL APPROACH LATE FRIDAY...AND
APPEARS WILL SLOWLY ROLL THROUGH...DUE TO WSW TO SW FLOW
ALOFT...FRIDAY NIGHT AND SATURDAY MORNING TIME FRAME. APPEARS BEST
CHANCE OF SHOWERS AND THUNDERSTORMS WOULD BE ASSOCIATED WITH THE
FROPA DURING THIS TIME. GFS AND ECMWF INDICATE THE FRONT WILL SHIFT
TO OUR SOUTH BY LATE SAT AND SUNDAY. UNCERTAINTIES REMAIN WITH
TIMING OF FROPA AND CONFIDENCE REGARDING HOW FAR TO OUR SOUTH IT
WILL PUSH SUNDAY...WITH MOISTURE RETURN BACK INTO OUR AREA POSSIBLE
MONDAY.
&&
.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS FOR MUCH OF THE PERIOD...EXCEPT POSSIBLE MVFR
CIGS AND VSBYS DURING THE PREDAWN HOURS TUESDAY MORNING AND
CONTINUING UNTIL AROUND 15Z.
AT THE SURFACE...HIGH PRESSURE IS OFF THE SOUTHEAST COAST BRINGING
AN ONSHORE FLOW WITH MOISTURE INCREASING THROUGH THE TAF PERIOD. AT
UPPER LEVELS THE FLOW IS ZONAL WITH ONE SHORTWAVE OVER MS/AL AND
ANOTHER SHORTWAVE OVER THE ARKLATEX REGION. THE FIRST SHORTWAVE WILL
MOVE OVER THE AREA LATER THIS EVENING BRINGING A CHANCE FOR SHOWERS
MAINLY AROUND MIDNIGHT ACCORDING TO LATEST HRRR RUN. WILL COVER WITH
-SHRA IN A TEMPO GROUP FOR ALL TAF SITES EXCEPT OGB. THE NEXT
SHORTWAVE WILL APPROACH DURING THE PREDAWN HOURS TUESDAY BRINGING AN
ANOTHER CHANCE OF SHOWERS...ESPECIALLY AROUND SUNRISE. WILL MENTION
VCSH AT ALL TAF SITES AFTER 10Z AS CONFIDENCE IS LOW CONCERNING
PRECIPITATION COVERAGE AND TIMING AFTER THAT TIME PERIOD. SFC WINDS
WILL BE MAINLY E TO SE OVERNIGHT BECOMING VARIABLE AFTER SUNRISE
TUESDAY. WIND SPEEDS WILL BE GENERALLY LESS THAN 10 KNOTS THROUGH
THE TAF PERIOD.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE TUESDAY NIGHT
THROUGH WEDNESDAY AS A FRONTAL BOUNDARY STALLS ACROSS THE REGION.
MOIST PATTERN CONTINUES FOR THURSDAY AND FRIDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
747 PM EDT MON APR 6 2015
.SYNOPSIS...
HIGH PRESSURE TO OUR EAST WILL MAINTAIN SUFFICIENT ATMOSPHERIC
MOISTURE OVER OUR REGION THROUGH MUCH OF THIS WEEK. A FRONT WILL
MOVE THROUGH LATE FRIDAY AND EARLY SATURDAY AND PUSH TO OUR SOUTH BY
LATE SATURDAY INTO SUNDAY. THESE FACTORS...DAYTIME HEATING...AND
SOME UPPER ENERGY...WILL PROVIDE A CHANCE OF SHOWERS AND POSSIBLE
THUNDERSTORMS AT TIMES THIS WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
ZONAL UPPER LEVEL FLOW WILL CONTINUE OVER THE SERN STATES THROUGH
TONIGHT. AT 18Z THERE IS AN AREA OF SHOWERS AND THUNDERSTORMS
ASSOCIATED WITH A SHORTWAVE EXTENDING FROM SOUTH CENTRAL KY SOUTH
ACROSS TENNESSEE AND CENTRAL AL. THIS SHORTWAVE WILL MOVE OVER
THE AREA LATER TONIGHT.
LATEST MESO-ANALYSIS...20Z...INDICATES WEAK INSTABILITY ACROSS
EAST CENTRAL GEORGIA WITH MID LEVEL CAPPING. AIR MASS OVER CENTRAL
MIDLANDS MORE STABLE WITH DRIER LOW LEVEL AIR. RADAR INDICATING
VERY LIGHT ISOLATED SHOWERS NEAR AGS...BUT NOTHING SIGNIFICANT.
LITTLE CHANGE EXPECTED FOR THE NEXT FEW HOURS INTO THE EARLY
EVENING AS SHORT WAVE REMAINS WEST OF AREA AND MID LEVEL CAP
PRESENT LIMITING CONVECTION.
THERE WILL BE WEAK INSTABILITY AS THE SHORTWAVE CROSSES THE AREA
LATE TONIGHT. WITH INCREASING MOISTURE THERE WILL BE A CHANCE OF
SHOWERS AND THE POSSIBILITY OF SOME THUNDER. MET POPS ARE MUCH
HIGHER OVERNIGHT THAN THE MAV POPS. WILL GO THE MIDDLE ROAD AND
AND KEEP POPS MAINLY IN THE 40 TO 50 PERCENT RANGE. BEST RAIN
CHANCES WILL BE AFTER MIDNIGHT. AFTER HIGHS THIS AFTERNOON IN THE
UPPER 70S...LOWS TONIGHT WILL BE IN THE LOWER 60S WITH A LIGHT
SOUTH TO SOUTHEAST WIND.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
WEAK UPPER TROUGH AXIS WILL REMAIN NEAR THE WEST COAST...WHILE A
FLAT UPPER RIDGE REMAINS OVER THE GULF OF MEXICO AND GULF COAST. AN
EMBEDDED UPPER DISTURBANCE WILL TRACK EAST ACROSS OUR REGION TUESDAY.
SURFACE HIGH PRESSURE WILL PUSH A LITTLE FARTHER TO THE SE
OFFSHORE...AND DIRECT HIGHER MOISTURE INTO OUR REGION. ABOVE FACTORS
PLUS DIURNAL HEATING AND ANY CONVERGENCE ALONG SURFACE TROUGH OR SEA
BREEZE EXPECTED TO RESULT IN SCATTERED SHOWERS. SLIGHT CHANCE
THUNDER POSSIBLE AS WELL DUE TO INDICATIONS OF WEAK TO MODERATE
INSTABILITY.
WEAK UPPER RIDGE AXIS TO SHIFT OVERHEAD WEDNESDAY BEHIND DEPARTING
UPPER ENERGY...AND ATMOSPHERE APPEARS WILL BE A LITTLE LESS MOIST
WED AS WELL. THESE FACTORS SUGGEST LOWER POPS FOR WED.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
UPPER TROUGH TO SHIFT EAST FROM THE NORTHERN AND CENTRAL ROCKIES
ACROSS THE NORTHERN AND CENTRAL PLAINS...AND EVENTUALLY INTO THE
GREAT LAKES AND NEW ENGLAND REGION THROUGH THE PERIOD. WEAK UPPER
RIDGE OVER THE GULF OF MEXICO WILL WEAKEN AND SHIFT EAST ACROSS
FLORIDA AND INTO THE WESTERN ATLANTIC. FOR OUR REGION...THIS WILL
GENERALLY TRANSLATE INTO A GENERAL WSW UPPER FLOW WITH A SERIES OF
UPPER DISTURBANCES TRACKING ACROSS. AT THE SURFACE...A MOIST
GENERALLY S TO SW LOW LEVEL FLOW EXPECTED TO CONTINUE. THIS ALONG
WITH DIURNAL HEATING EXPECTED TO RESULT IN SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS. A COLD FRONT WILL APPROACH LATE FRIDAY...AND
APPEARS WILL SLOWLY ROLL THROUGH...DUE TO WSW TO SW FLOW
ALOFT...FRIDAY NIGHT AND SATURDAY MORNING TIME FRAME. APPEARS BEST
CHANCE OF SHOWERS AND THUNDERSTORMS WOULD BE ASSOCIATED WITH THE
FROPA DURING THIS TIME. GFS AND ECMWF INDICATE THE FRONT WILL SHIFT
TO OUR SOUTH BY LATE SAT AND SUNDAY. UNCERTAINTIES REMAIN WITH
TIMING OF FROPA AND CONFIDENCE REGARDING HOW FAR TO OUR SOUTH IT
WILL PUSH SUNDAY...WITH MOISTURE RETURN BACK INTO OUR AREA POSSIBLE
MONDAY.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS FOR MUCH OF THE PERIOD...EXCEPT POSSIBLE MVFR
CIGS AND VSBYS DURING THE PREDAWN HOURS TUESDAY MORNING AND
CONTINUING UNTIL AROUND 15Z.
AT THE SURFACE...HIGH PRESSURE IS OFF THE SOUTHEAST COAST BRINGING
AN ONSHORE FLOW WITH MOISTURE INCREASING THROUGH THE TAF PERIOD. AT
UPPER LEVELS THE FLOW IS ZONAL WITH A SHORTWAVE OVER THE ARKLATEX
REGION. THIS SHORTWAVE WILL MOVE OVER THE AREA DURING THE PREDAWN
HOURS TUESDAY BRINGING AN INCREASED CHANCE OF SHOWERS...ESPECIALLY
AROUND SUNRISE. LATEST HRRR KEEPS SHOWERS OUT OF THE FORECAST AREA
THROUGH 10Z TUESDAY. WILL MENTION VCSH AT ALL TAF SITES AFTER 14Z AS
CONFIDENCE IS LOW CONCERNING PRECIPITATION COVERAGE AND TIMING AFTER
THAT TIME PERIOD. SFC WINDS WILL BE MAINLY E TO SE OVERNIGHT
BECOMING VARIABLE AFTER SUNRISE TUESDAY. WIND SPEEDS WILL BE
GENERALLY LESS THAN 10 KNOTS THROUGH THE TAF PERIOD.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE TUESDAY NIGHT
THROUGH WEDNESDAY AS A FRONTAL BOUNDARY STALLS ACROSS THE REGION.
MOIST PATTERN CONTINUES FOR THURSDAY AND FRIDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1257 PM CDT SUN APR 5 2015
.SHORT TERM...
417 AM CDT
TODAY THROUGH TUESDAY NIGHT...
DRY...MILD AND BREEZY CONDITIONS TO CONTINUE ACROSS THE FORECAST
AREA TODAY AS WFO LOT CWA SITS BENEATH WESTERLY FLOW ALOFT
DOWNSTREAM OF BROAD UPPER RIDGE OVER THE CENTRAL CONUS. PERSISTENT
WARM ADVECTION FROM THE WEST-SOUTHWEST IN THE LOW LEVELS WILL MAKE
FOR WARMER TEMPS TODAY...WHILE A NEARLY STATIONARY FRONT TAKES
SHAPE TO OUR NORTH AND REMAINS THE FOCUS FOR PRECIPITATION THROUGH
TONIGHT. RADAR HAS DEPICTED A FEW WEAK RETURNS FROM MID-LEVEL
CLOUD BASES MAINLY ABOVE 10 KFT OVERNIGHT/EARLY THIS
MORNING...THOUGH DRY LOW LEVELS EXPECTED TO RESULT IN JUST A
PERIOD OF PARTLY-MOSTLY CLOUDY SKIES AND SOME VIRGA ACROSS
NORTHERN SECTIONS OF THE CWA THIS MORNING AS A MID-LEVEL SHORT
WAVE PASSES. CLOUDS SHOULD DECREASE BY THIS AFTERNOON...WITH
TEMPERATURES WARMING INTO THE MID-UPPER 60S. SOUTHWEST WINDS MAY
GUST AROUND 25 MPH DURING THE LATE MORNING AND MIDDAY
HOURS...THOUGH SHOULD DIMINISH A BIT THIS AFTERNOON AS MID-LEVEL
WINDS DECREASE. AS WINDS SLACK OFF THIS AFTERNOON...A LAKE BREEZE
WILL LIKELY DEVELOP AND TURN WINDS TO THE SOUTHEAST ALONG THE FAR
NORTH SHORE AREA WITH TEMPS COOLING OFF INTO THE 50S/40S AS
EVENING APPROACHES. THE LAKE BREEZE MAY COMBINE WITH SAGGING COLD
FRONT TO OUR NORTH DURING THE EVENING...THOUGH PERSISTENT SOUTH-
SOUTHWEST WINDS IN AND ABOVE THE BOUNDARY LAYER SHOULD KEEP IT
FROM MAKING MUCH GROUND INTO NORTHERN IL AND MODELS GENERALLY KEEP
IT ALONG THE IL/WI BORDER THROUGH MONDAY MORNING.
ON MONDAY...LOW PRESSURE DEVELOPS ACROSS THE HIGH PLAINS IN
RESPONSE TO A SERIES OF MINOR SHORT WAVES AND JET ENERGY EMANATING
FROM AN UPPER TROUGH ALONG THE WEST COAST. TO OUR
SOUTH...EXTENSIVE AREA OF HIGH PRESSURE FROM THE ARKLATEX TO THE
CAROLINAS MOVES OFF TO THE EAST AND LOW LEVEL FLOW OFF OF THE
WESTERN GULF BEGINS TO ADVECT NORTHWARD ACROSS THE PLAINS AND
MISSISSIPPI VALLEY. LOCALLY... FORECAST SOUNDINGS DEPICT LOW LEVEL
MOISTENING DURING THE AFTERNOON AND EVENING HOURS OF MONDAY WITH
SOME LIGHT QPF BEING GENERATED. THIS MAY RESULT IN SOME LIGHT
RAIN/DRIZZLE MONDAY AFTERNOON ESPECIALLY ACROSS SOUTHERN AND
WESTERN PARTS OF THE CWA. RAIN CHANCES WILL INCREASE MONDAY NIGHT
HOWEVER...AS SURFACE WAVE MOVES INTO THE MISSOURI VALLEY AND
MODEST LOW LEVEL JET AHEAD OF IT INCREASES MOISTURE TRANSPORT INTO
THE REGION. COINCIDENT WITH THIS...FRONT TO OUR NORTH DEVELOPS
SOUTH INTO IL/IN AHEAD OF APPROACHING SURFACE WAVE. TIGHTENING LOW
LEVEL BAROCLINIC ZONE WILL BECOME FOCUS FOR LIFT MONDAY NIGHT AS
WAVE APPROACHES WITH ASSOCIATED INCREASE IN POPS. STEEP LAPSE
RATES OF 7-8.0 C/KM IN FORECAST SOUNDINGS INDICATE THUNDER
POTENTIAL FOR MONDAY NIGHT. RAIN AND OCCASIONAL THUNDER POTENTIAL
LINGER TUESDAY AS THE FRONTAL WAVE MOVES TOWARD THE LOWER OHIO
VALLEY AND SLOWLY WEAKENS.
RATZER
&&
.LONG TERM...
417 AM CDT
WEDNESDAY THROUGH SATURDAY...
WEAKENING SURFACE WAVE TRACKS THROUGH OHIO VALLEY WEDNESDAY...
WITH FRONT SAGGING SOUTH ACROSS CENTRAL IL/IN BEHIND IT. AFTER
SOME LINGERING MORNING SHOWERS...IT APPEARS WEAK SHORT WAVE
RIDGING AND COOL LOW LEVEL NORTHEAST FLOW WILL LIMIT RAIN CHANCES
DURING THE MIDDAY AND AFTERNOON HOURS...PROBABLY THE BEST CHANCE
OF DRY WEATHER THROUGH FRIDAY. WEDNESDAY NIGHT SEES A RENEWED PUSH
OF WARM ADVECTION ABOVE THE FRONTAL ZONE AS ANOTHER SHORT WAVE
RIPPLES THROUGH WEST-SOUTHWEST FLOW ALOFT.
THURSDAY-FRIDAY THE MAIN UPPER TROUGH/CLOSED LOW INITIALLY ALONG
THE WEST COAST MOVES INLAND...WITH A JET STREAK ROUNDING THE BASE
AND DEEPENING THE SYSTEM OVER THE CENTRAL ROCKIES WEDNESDAY NIGHT
AND SURFACE CYCLOGENESIS OCCURRING OVER THE HIGH PLAINS. THIS
DEEPENING SYSTEM MOVES TO THE MID-MISSOURI VALLEY BY LATE THURSDAY
WITH THE FRONT ACROSS IL/IN LIFTING BACK NORTH AS A WARM FRONT.
THE POTENTIAL EXISTS FOR SEVERE WEATHER DURING THIS TIME WITH
STRONG DEEP LAYER SHEAR AND INCREASING INSTABILITY IN WARM/MOIST
WARM SECTOR AIR MASS ALONG/SOUTH OF THE WARM FRONT. SPC DAY 4
OUTLOOK DOES INCLUDE MUCH OF THE AREA IN A RISK FOR SEVERE
WEATHER. PERIODS OF SHOWERS/THUNDERSTORMS APPEAR LIKELY THROUGH
FRIDAY MORNING AS THE LOW OCCLUDES AND EVENTUALLY LIFTS INTO THE
UPPER MISSISSIPPI VALLEY ON FRIDAY. GFS AND ECMWF RUNS BOTH
INDICATE THE OCCLUDED FRONT LIFTING NORTHEAST ACROSS THE AREA
FRIDAY...WITH DRIER AIR MOVING IN BEHIND IT AND DIMINISHING PRECIP
CHANCES INTO FRIDAY NIGHT AND SATURDAY. WITH FRONT STRETCHED WEST-
EAST ACROSS CWA...LARGE TEMPERATURE GRADIENT MAKES DAILY TEMP
FORECAST DIFFICULT. WILL LIKELY SEE A LARGE RANGE FROM 40S/50S
NORTH WHERE NORTHEAST FLOW OFF THE LAKES OCCURS...TO THE 70S SOUTH
OF THE FRONT ACROSS CENTRAL IL/IN INCLUDING SOUTHERN CWA.
RATZER
&&
.FIRE WEATHER...
455 AM CDT
THE FIRE WEATHER WATCH HAS BEEN CANCELLED FOR TODAY.
DRY...MILD AND BREEZY CONDITIONS ARE ANTICIPATED ACROSS THE AREA
AGAIN TODAY. HOWEVER...RED FLAG WARNING CRITERIA IS NOT EXPECTED
TO BE MET.
AFTERNOON RELATIVE HUMIDITY VALUES ARE EXPECTED TO FALL TO THE 20
TO 25 PERCENT RANGE...WITH TEMPERATURES TOPPING OUT IN THE MID TO
UPPER 60S AND DEW POINTS MIXING OUT TO THE UPPER 20S TO AROUND 30
DEGREES. HOWEVER...WHILE SOUTHWEST WINDS MAY GUST AROUND 25 MPH BY
LATE THIS MORNING...WINDS ARE EXPECTED TO DIMINISH THIS AFTERNOON
DURING THE TIME OF LOWEST RELATIVE HUMIDITY...AND SUSTAINED 20
FOOT WINDS ARE EXPECTED TO REMAIN BELOW 20 MPH THROUGH THE DAY.
SINCE CONDITIONS ARE NOT EXPECTED TO DETERIORATE TO CRITICAL RED
FLAG CRITERIA...THE FIRE WEATHER WATCH HAS BEEN CANCELLED.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* GUSTY SOUTHWEST WINDS THIS AFTERNOON BECOMING MORE SOUTH
SOUTHEAST EARLY THIS EVENING...AND POSSIBLY EAST NORTHEAST
BRIEFLY.
* A SHIFT BACK TOWARDS EASTERLY WINDS WITH POTENTIAL FOR MVFR
CEILINGS VERY LATE IN THE FORECAST PERIOD FOR ORD.
RODRIGUEZ
//DISCUSSION...UPDATED 18Z...
VFR CONDITIONS IN PLACE THIS AFTERNOON WHILE SOUTHWEST WINDS GUST
TO AROUND 20 KT. VFR CONDITIONS WILL PREVAIL FOR MOST OF THE
FORECAST PERIOD...WHILE A SOUTHERLY WIND LIKELY REMAINS THE
PREDOMINANT WIND DIRECTION. HOWEVER...A FRONT JUST TO THE NORTH OF
THE TERMINALS COULD DROP SOUTH SOME LATE THIS AFTERNOON AND
EARLY EVENING. IF THIS WERE TO OCCUR...A SHIFT TOWARDS AN EAST
NORTHEAST WIND WOULD OCCUR. LATEST THINKING IS THAT THE FRONT
WILL LIKELY DROP SOUTH AND COME CLOSE TO PRIMARILY ORD WITH AN
EASTERLY COMPONENT POSSIBLE BRIEFLY THIS EVENING...AND HAVE
REFLECTED THIS IN THE TAF. SOUTHERLY FLOW WILL PREVAIL ONCE AGAIN
LATER TONIGHT AND MONDAY BUT WITH THIS FRONT HAVING A BETTER
CHANCE OF DROPPING SOUTH VERY LATE IN THE FORECAST PERIOD. THIS
WOULD LIKELY SHIFT THE WINDS ONCE AGAIN AND AS THAT
OCCURS...UPSTREAM MVFR STRATUS WILL LIKELY MOVE ACROSS THE
TERMINALS.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE WITH WIND SPEED/DIRECTION IN THE NEAR
TERM...MEDIUM CONFIDENCE THIS EVENING AND LOW CONFIDENCE WITH
POTENTIAL FOR AN EAST NORTHEAST WIND THIS EVENING.
* MEDIUM CONFIDENCE WITH WIND SHIFT AND MVFR CEILINGS VERY LATE
IN THE FORECAST PERIOD.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
* MONDAY NIGHT AND TUESDAY...SHRA/TSRA. IFR/LIFR. NORTHEAST WINDS.
* WEDNESDAY...IFR/LIFR. CHANCE OF DRIZZLE. EAST WINDS.
* WEDNESAY NIGHT THROUGH THURSDAY NIGHT...SHRA/TSRA. IFR/LIFR.
EAST WINDS.
* FRIDAY...CHANCE OF SHRA. MVFR POSSIBLE. SOUTHWEST WINDS.
* SATURDAY...DRY/VFR. GUSTY WEST WINDS.
&&
.MARINE...
323 AM...A FRONTAL BOUNDARY WILL SAG ACROSS THE SOUTH CENTRAL
PORTIONS OF THE LAKE THIS AFTERNOON AND REMAIN THERE THROUGH
MONDAY MORNING...BEFORE FINALLY MOVING JUST SOUTH OF THE LAKE BY
MONDAY EVENING. THE FRONT IS THEN EXPECTED TO REMAIN GENERALLY
STATIONARY THRU MID WEEK AS LOW PRESSURE MOVES ALONG THE FRONT
TUESDAY NIGHT. THIS WILL TIGHTEN THE GRADIENT WITH 30 KTS POSSIBLE
MONDAY NIGHT INTO TUESDAY...MAINLY ACROSS THE NORTH HALF/NORTH TWO
THIRDS OF THE LAKE. A STRONG LOW IS EXPECTED TO MOVE ACROSS THE
WESTERN LAKES FRIDAY INTO SATURDAY. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1255 PM CDT Sun Apr 5 2015
.UPDATE...
ISSUED AT 1047 AM CDT SUN APR 5 2015
High pressure ridge axis off to the east this morning, with gusty
southerly flow dominating the region. Some cirrus to the south,
edging into Central Illinois, and will provide some scattered thin
cloud cover. However, the clouds will have little impact on the
warming into the mid to upper 60s today. No updates anticipated at
this time.
&&
.SHORT TERM...(Today)
ISSUED AT 254 AM CDT SUN APR 5 2015
Latest surface analysis showing high pressure over south central
Kentucky with the coldest temperatures, upper 20s to lower 30s,
located near the large fair weather system. Meanwhile, a frontal
boundary was located over northern Iowa eastward through extreme
southern Wisconsin with a band of showers occurring mainly north of
the boundary. The last few satellite loops indicating some patchy
mid clouds spilling east across the region this morning but most of
the forecast soundings and time height cross sections continue to
suggest the bulk of the more extensive cloud cover today will remain
to our north. Forecast soundings off the HRRR and Rapid Refresh
depicting another well mixed boundary layer again today which should
result in temperatures at or above guid values, and with the deep
mixing occurring this afternoon, rather low relative humidities and
gusty southwest winds.
&&
.LONG TERM...(Tonight through Saturday)
ISSUED AT 254 AM CDT SUN APR 5 2015
Position of frontal boundary will remain a significant challenge
much of the week. General philosophy remains the same as the
previous model runs, although with a bit of a slower southward push
late Tuesday. Because of that, bumped up high temperatures a few
degrees. Much of the model guidance shows upper 70s across the
southwest CWA Tuesday afternoon, although the far north is expected
to be about 10 degrees cooler with the front much closer.
Temperatures will generally be in the 60s Wednesday with some lower
70s south, as the front drops to near the I-70 corridor before
heading back north. Also warmed Thursday highs with mid-upper 70s
common.
With much of the week featuring rain chances, have tried to do some
refining of potential dry periods. With the atmosphere remaining
capped much of Monday, have scaled back PoP`s to mainly the
afternoon, and featured generally slight chances except far
northwest and far southeast. Monday night, have continued the likely
PoP`s most areas, as thunderstorms expand along the frontal boundary
just to our north. However, the precipitation threat will diminish
from south to north as capping becomes more prominent in the warm
sector.
With the front sagging southward, it currently appears Wednesday
should be dry over much of the area north of I-72, but PoP`s ramp up
again quickly as developing low pressure over the central Plains
drags the front northward once again. A closed upper low, which will
develop after a wave moves onshore Tuesday, continues to be a
pivotal player in the ultimate evolution of this front/low. The
longer range models are coming into closer agreement, although the
GFS remains on a faster track (ECMWF still has it over northwest
Wisconsin by Saturday morning, while the GFS is over Lake Huron).
Thursday remains the most unstable period, with the GFS-progged
CAPE`s approaching 2000 J/kg in the afternoon, although 0-6km bulk
shear values expected to be low, favoring more of a hail/wind severe
potential.
With the upper low remaining rather prominent late in the week, the
corresponding surface cyclone will be wrapping up, with a prominent
dry slot punching through on Friday. Have maintained some low chance
PoP`s on Friday, although this would mainly be in across the eastern
eastern CWA during the morning. With breezy southwest winds and
clearing skies, temperatures are still expected to reach near 70.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 1251 PM CDT SUN APR 5 2015
Not much of a shift in the forecast so far. Southwesterly winds a
bit gusty today as sunshine/heating helps to mix down winds aloft
as well as a decent pressure gradient at the sfc. VFR through the
day as cirrus is about all that is streaming over ILX terminals in
a fairly dry airmass. Overnight, winds stay up with the pressure
gradient persisting...and becoming more southerly as the high
pressure ridge axis slips off to the east. Moisture and WAA
resulting in a developing stratus deck in the early morning hours.
Keeping it VFR for now, but timing of the drop to MVFR cigs
starting to show up in half the guidance after 15z or so.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HJS
SHORT TERM...Smith
LONG TERM...Geelhart
AVIATION...HJS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1106 AM CDT SUN APR 5 2015
.SHORT TERM...
417 AM CDT
TODAY THROUGH TUESDAY NIGHT...
DRY...MILD AND BREEZY CONDITIONS TO CONTINUE ACROSS THE FORECAST
AREA TODAY AS WFO LOT CWA SITS BENEATH WESTERLY FLOW ALOFT
DOWNSTREAM OF BROAD UPPER RIDGE OVER THE CENTRAL CONUS. PERSISTENT
WARM ADVECTION FROM THE WEST-SOUTHWEST IN THE LOW LEVELS WILL MAKE
FOR WARMER TEMPS TODAY...WHILE A NEARLY STATIONARY FRONT TAKES
SHAPE TO OUR NORTH AND REMAINS THE FOCUS FOR PRECIPITATION THROUGH
TONIGHT. RADAR HAS DEPICTED A FEW WEAK RETURNS FROM MID-LEVEL
CLOUD BASES MAINLY ABOVE 10 KFT OVERNIGHT/EARLY THIS
MORNING...THOUGH DRY LOW LEVELS EXPECTED TO RESULT IN JUST A
PERIOD OF PARTLY-MOSTLY CLOUDY SKIES AND SOME VIRGA ACROSS
NORTHERN SECTIONS OF THE CWA THIS MORNING AS A MID-LEVEL SHORT
WAVE PASSES. CLOUDS SHOULD DECREASE BY THIS AFTERNOON...WITH
TEMPERATURES WARMING INTO THE MID-UPPER 60S. SOUTHWEST WINDS MAY
GUST AROUND 25 MPH DURING THE LATE MORNING AND MIDDAY
HOURS...THOUGH SHOULD DIMINISH A BIT THIS AFTERNOON AS MID-LEVEL
WINDS DECREASE. AS WINDS SLACK OFF THIS AFTERNOON...A LAKE BREEZE
WILL LIKELY DEVELOP AND TURN WINDS TO THE SOUTHEAST ALONG THE FAR
NORTH SHORE AREA WITH TEMPS COOLING OFF INTO THE 50S/40S AS
EVENING APPROACHES. THE LAKE BREEZE MAY COMBINE WITH SAGGING COLD
FRONT TO OUR NORTH DURING THE EVENING...THOUGH PERSISTENT SOUTH-
SOUTHWEST WINDS IN AND ABOVE THE BOUNDARY LAYER SHOULD KEEP IT
FROM MAKING MUCH GROUND INTO NORTHERN IL AND MODELS GENERALLY KEEP
IT ALONG THE IL/WI BORDER THROUGH MONDAY MORNING.
ON MONDAY...LOW PRESSURE DEVELOPS ACROSS THE HIGH PLAINS IN
RESPONSE TO A SERIES OF MINOR SHORT WAVES AND JET ENERGY EMANATING
FROM AN UPPER TROUGH ALONG THE WEST COAST. TO OUR
SOUTH...EXTENSIVE AREA OF HIGH PRESSURE FROM THE ARKLATEX TO THE
CAROLINAS MOVES OFF TO THE EAST AND LOW LEVEL FLOW OFF OF THE
WESTERN GULF BEGINS TO ADVECT NORTHWARD ACROSS THE PLAINS AND
MISSISSIPPI VALLEY. LOCALLY... FORECAST SOUNDINGS DEPICT LOW LEVEL
MOISTENING DURING THE AFTERNOON AND EVENING HOURS OF MONDAY WITH
SOME LIGHT QPF BEING GENERATED. THIS MAY RESULT IN SOME LIGHT
RAIN/DRIZZLE MONDAY AFTERNOON ESPECIALLY ACROSS SOUTHERN AND
WESTERN PARTS OF THE CWA. RAIN CHANCES WILL INCREASE MONDAY NIGHT
HOWEVER...AS SURFACE WAVE MOVES INTO THE MISSOURI VALLEY AND
MODEST LOW LEVEL JET AHEAD OF IT INCREASES MOISTURE TRANSPORT INTO
THE REGION. COINCIDENT WITH THIS...FRONT TO OUR NORTH DEVELOPS
SOUTH INTO IL/IN AHEAD OF APPROACHING SURFACE WAVE. TIGHTENING LOW
LEVEL BAROCLINIC ZONE WILL BECOME FOCUS FOR LIFT MONDAY NIGHT AS
WAVE APPROACHES WITH ASSOCIATED INCREASE IN POPS. STEEP LAPSE
RATES OF 7-8.0 C/KM IN FORECAST SOUNDINGS INDICATE THUNDER
POTENTIAL FOR MONDAY NIGHT. RAIN AND OCCASIONAL THUNDER POTENTIAL
LINGER TUESDAY AS THE FRONTAL WAVE MOVES TOWARD THE LOWER OHIO
VALLEY AND SLOWLY WEAKENS.
RATZER
&&
.LONG TERM...
417 AM CDT
WEDNESDAY THROUGH SATURDAY...
WEAKENING SURFACE WAVE TRACKS THROUGH OHIO VALLEY WEDNESDAY...
WITH FRONT SAGGING SOUTH ACROSS CENTRAL IL/IN BEHIND IT. AFTER
SOME LINGERING MORNING SHOWERS...IT APPEARS WEAK SHORT WAVE
RIDGING AND COOL LOW LEVEL NORTHEAST FLOW WILL LIMIT RAIN CHANCES
DURING THE MIDDAY AND AFTERNOON HOURS...PROBABLY THE BEST CHANCE
OF DRY WEATHER THROUGH FRIDAY. WEDNESDAY NIGHT SEES A RENEWED PUSH
OF WARM ADVECTION ABOVE THE FRONTAL ZONE AS ANOTHER SHORT WAVE
RIPPLES THROUGH WEST-SOUTHWEST FLOW ALOFT.
THURSDAY-FRIDAY THE MAIN UPPER TROUGH/CLOSED LOW INITIALLY ALONG
THE WEST COAST MOVES INLAND...WITH A JET STREAK ROUNDING THE BASE
AND DEEPENING THE SYSTEM OVER THE CENTRAL ROCKIES WEDNESDAY NIGHT
AND SURFACE CYCLOGENESIS OCCURRING OVER THE HIGH PLAINS. THIS
DEEPENING SYSTEM MOVES TO THE MID-MISSOURI VALLEY BY LATE THURSDAY
WITH THE FRONT ACROSS IL/IN LIFTING BACK NORTH AS A WARM FRONT.
THE POTENTIAL EXISTS FOR SEVERE WEATHER DURING THIS TIME WITH
STRONG DEEP LAYER SHEAR AND INCREASING INSTABILITY IN WARM/MOIST
WARM SECTOR AIR MASS ALONG/SOUTH OF THE WARM FRONT. SPC DAY 4
OUTLOOK DOES INCLUDE MUCH OF THE AREA IN A RISK FOR SEVERE
WEATHER. PERIODS OF SHOWERS/THUNDERSTORMS APPEAR LIKELY THROUGH
FRIDAY MORNING AS THE LOW OCCLUDES AND EVENTUALLY LIFTS INTO THE
UPPER MISSISSIPPI VALLEY ON FRIDAY. GFS AND ECMWF RUNS BOTH
INDICATE THE OCCLUDED FRONT LIFTING NORTHEAST ACROSS THE AREA
FRIDAY...WITH DRIER AIR MOVING IN BEHIND IT AND DIMINISHING PRECIP
CHANCES INTO FRIDAY NIGHT AND SATURDAY. WITH FRONT STRETCHED WEST-
EAST ACROSS CWA...LARGE TEMPERATURE GRADIENT MAKES DAILY TEMP
FORECAST DIFFICULT. WILL LIKELY SEE A LARGE RANGE FROM 40S/50S
NORTH WHERE NORTHEAST FLOW OFF THE LAKES OCCURS...TO THE 70S SOUTH
OF THE FRONT ACROSS CENTRAL IL/IN INCLUDING SOUTHERN CWA.
RATZER
&&
.FIRE WEATHER...
455 AM CDT
THE FIRE WEATHER WATCH HAS BEEN CANCELLED FOR TODAY.
DRY...MILD AND BREEZY CONDITIONS ARE ANTICIPATED ACROSS THE AREA
AGAIN TODAY. HOWEVER...RED FLAG WARNING CRITERIA IS NOT EXPECTED
TO BE MET.
AFTERNOON RELATIVE HUMIDITY VALUES ARE EXPECTED TO FALL TO THE 20
TO 25 PERCENT RANGE...WITH TEMPERATURES TOPPING OUT IN THE MID TO
UPPER 60S AND DEW POINTS MIXING OUT TO THE UPPER 20S TO AROUND 30
DEGREES. HOWEVER...WHILE SOUTHWEST WINDS MAY GUST AROUND 25 MPH BY
LATE THIS MORNING...WINDS ARE EXPECTED TO DIMINISH THIS AFTERNOON
DURING THE TIME OF LOWEST RELATIVE HUMIDITY...AND SUSTAINED 20
FOOT WINDS ARE EXPECTED TO REMAIN BELOW 20 MPH THROUGH THE DAY.
SINCE CONDITIONS ARE NOT EXPECTED TO DETERIORATE TO CRITICAL RED
FLAG CRITERIA...THE FIRE WEATHER WATCH HAS BEEN CANCELLED.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* GUSTY SOUTHWEST WINDS THRU MID AFTERNOON.
CMS/RODRIGUEZ
//DISCUSSION...UPDATED 12Z...
SOUTHWESTERLY WINDS WILL STEADILY INCREASE THIS MORNING WITH GUSTS
AS HIGH AS THE MID 20 KT RANGE AS STRONGER WINDS ALOFT BEGIN TO
MIX TO THE SURFACE. HOWEVER...THESE STRONGER WINDS ALOFT WILL
SLOWLY DIMINISH INTO THIS AFTERNOON. THUS EXPECTING PREVAILING
WINDS/GUSTS TO ALSO SLOWLY DIMINISH INTO THE AFTERNOON. WINDS WILL
TURN MORE SOUTHERLY AFTER SUNSET AND REMAIN SOUTHERLY INTO MONDAY
MORNING WITH SPEEDS GENERALLY BELOW 10 KT.
MID CLOUDS WILL CONTINUE TO MOVE ACROSS THE AREA THIS MORNING
WITH SOME HIGH BASED CU POSSIBLE THIS AFTERNOON. INCREASING HIGH
CLOUDS THIS EVENING LOWERING TO A MID DECK MONDAY MORNING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM FOR WINDS THRU THE PERIOD.
CMS/RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
* MONDAY NIGHT AND TUESDAY...SHRA/TSRA. IFR/LIFR. NORTHEAST WINDS.
* WEDNESDAY...IFR/LIFR. CHANCE OF DRIZZLE. EAST WINDS.
* WEDNESAY NIGHT THROUGH THURSDAY NIGHT...SHRA/TSRA. IFR/LIFR.
EAST WINDS.
* FRIDAY...CHANCE OF SHRA. MVFR POSSIBLE. SOUTHWEST WINDS.
* SATURDAY...DRY/VFR. GUSTY WEST WINDS.
&&
.MARINE...
323 AM...A FRONTAL BOUNDARY WILL SAG ACROSS THE SOUTH CENTRAL
PORTIONS OF THE LAKE THIS AFTERNOON AND REMAIN THERE THROUGH
MONDAY MORNING...BEFORE FINALLY MOVING JUST SOUTH OF THE LAKE BY
MONDAY EVENING. THE FRONT IS THEN EXPECTED TO REMAIN GENERALLY
STATIONARY THRU MID WEEK AS LOW PRESSURE MOVES ALONG THE FRONT
TUESDAY NIGHT. THIS WILL TIGHTEN THE GRADIENT WITH 30 KTS POSSIBLE
MONDAY NIGHT INTO TUESDAY...MAINLY ACROSS THE NORTH HALF/NORTH TWO
THIRDS OF THE LAKE. A STRONG LOW IS EXPECTED TO MOVE ACROSS THE
WESTERN LAKES FRIDAY INTO SATURDAY. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1051 AM CDT Sun Apr 5 2015
.UPDATE...
ISSUED AT 1047 AM CDT SUN APR 5 2015
High pressure ridge axis off to the east this morning, with gusty
southerly flow dominating the region. Some cirrus to the south,
edging into Central Illinois, and will provide some scattered thin
cloud cover. However, the clouds will have little impact on the
warming into the mid to upper 60s today. No updates anticipated at
this time.
&&
.SHORT TERM...(Today)
ISSUED AT 254 AM CDT SUN APR 5 2015
Latest surface analysis showing high pressure over south central
Kentucky with the coldest temperatures, upper 20s to lower 30s,
located near the large fair weather system. Meanwhile, a frontal
boundary was located over northern Iowa eastward through extreme
southern Wisconsin with a band of showers occurring mainly north of
the boundary. The last few satellite loops indicating some patchy
mid clouds spilling east across the region this morning but most of
the forecast soundings and time height cross sections continue to
suggest the bulk of the more extensive cloud cover today will remain
to our north. Forecast soundings off the HRRR and Rapid Refresh
depicting another well mixed boundary layer again today which should
result in temperatures at or above guid values, and with the deep
mixing occurring this afternoon, rather low relative humidities and
gusty southwest winds.
&&
.LONG TERM...(Tonight through Saturday)
ISSUED AT 254 AM CDT SUN APR 5 2015
Position of frontal boundary will remain a significant challenge
much of the week. General philosophy remains the same as the
previous model runs, although with a bit of a slower southward push
late Tuesday. Because of that, bumped up high temperatures a few
degrees. Much of the model guidance shows upper 70s across the
southwest CWA Tuesday afternoon, although the far north is expected
to be about 10 degrees cooler with the front much closer.
Temperatures will generally be in the 60s Wednesday with some lower
70s south, as the front drops to near the I-70 corridor before
heading back north. Also warmed Thursday highs with mid-upper 70s
common.
With much of the week featuring rain chances, have tried to do some
refining of potential dry periods. With the atmosphere remaining
capped much of Monday, have scaled back PoP`s to mainly the
afternoon, and featured generally slight chances except far
northwest and far southeast. Monday night, have continued the likely
PoP`s most areas, as thunderstorms expand along the frontal boundary
just to our north. However, the precipitation threat will diminish
from south to north as capping becomes more prominent in the warm
sector.
With the front sagging southward, it currently appears Wednesday
should be dry over much of the area north of I-72, but PoP`s ramp up
again quickly as developing low pressure over the central Plains
drags the front northward once again. A closed upper low, which will
develop after a wave moves onshore Tuesday, continues to be a
pivotal player in the ultimate evolution of this front/low. The
longer range models are coming into closer agreement, although the
GFS remains on a faster track (ECMWF still has it over northwest
Wisconsin by Saturday morning, while the GFS is over Lake Huron).
Thursday remains the most unstable period, with the GFS-progged
CAPE`s approaching 2000 J/kg in the afternoon, although 0-6km bulk
shear values expected to be low, favoring more of a hail/wind severe
potential.
With the upper low remaining rather prominent late in the week, the
corresponding surface cyclone will be wrapping up, with a prominent
dry slot punching through on Friday. Have maintained some low chance
PoP`s on Friday, although this would mainly be in across the eastern
eastern CWA during the morning. With breezy southwest winds and
clearing skies, temperatures are still expected to reach near 70.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
ISSUED AT 610 AM CDT SUN APR 5 2015
VFR conditions are expected through tonight. High pressure off to
our southeast was producing a broad southwest flow across the region
early this morning. A frontal boundary to our north has produced
some scattered to broken mid clouds which have affected our northern
TAF sites early this morning. Those should push off to our east this
morning with some sct-bkn cirrus moving in for the remainder of the
day. Models indicating moisture will increase at all levels tonight
so we should see more clouds, especially later tonight when forecast
soundings suggest a band of low VFR or possibly MVFR cigs will track
from south to north across the TAF sites mainly after 06z. Surface
winds will be gusty out of the south to southwest today with prevailing
speeds of 12 to 17 kts with a few gusts up to 25 kts possible later
this morning through the mid afternoon hours before we see winds start
to decrease out of the south this evening to around 10 kts.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HJS
SHORT TERM...Smith
LONG TERM...Geelhart
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
641 AM CDT SUN APR 5 2015
.SHORT TERM...
417 AM CDT
TODAY THROUGH TUESDAY NIGHT...
DRY...MILD AND BREEZY CONDITIONS TO CONTINUE ACROSS THE FORECAST
AREA TODAY AS WFO LOT CWA SITS BENEATH WESTERLY FLOW ALOFT
DOWNSTREAM OF BROAD UPPER RIDGE OVER THE CENTRAL CONUS. PERSISTENT
WARM ADVECTION FROM THE WEST-SOUTHWEST IN THE LOW LEVELS WILL MAKE
FOR WARMER TEMPS TODAY...WHILE A NEARLY STATIONARY FRONT TAKES
SHAPE TO OUR NORTH AND REMAINS THE FOCUS FOR PRECIPITATION THROUGH
TONIGHT. RADAR HAS DEPICTED A FEW WEAK RETURNS FROM MID-LEVEL
CLOUD BASES MAINLY ABOVE 10 KFT OVERNIGHT/EARLY THIS
MORNING...THOUGH DRY LOW LEVELS EXPECTED TO RESULT IN JUST A
PERIOD OF PARTLY-MOSTLY CLOUDY SKIES AND SOME VIRGA ACROSS
NORTHERN SECTIONS OF THE CWA THIS MORNING AS A MID-LEVEL SHORT
WAVE PASSES. CLOUDS SHOULD DECREASE BY THIS AFTERNOON...WITH
TEMPERATURES WARMING INTO THE MID-UPPER 60S. SOUTHWEST WINDS MAY
GUST AROUND 25 MPH DURING THE LATE MORNING AND MIDDAY
HOURS...THOUGH SHOULD DIMINISH A BIT THIS AFTERNOON AS MID-LEVEL
WINDS DECREASE. AS WINDS SLACK OFF THIS AFTERNOON...A LAKE BREEZE
WILL LIKELY DEVELOP AND TURN WINDS TO THE SOUTHEAST ALONG THE FAR
NORTH SHORE AREA WITH TEMPS COOLING OFF INTO THE 50S/40S AS
EVENING APPROACHES. THE LAKE BREEZE MAY COMBINE WITH SAGGING COLD
FRONT TO OUR NORTH DURING THE EVENING...THOUGH PERSISTENT SOUTH-
SOUTHWEST WINDS IN AND ABOVE THE BOUNDARY LAYER SHOULD KEEP IT
FROM MAKING MUCH GROUND INTO NORTHERN IL AND MODELS GENERALLY KEEP
IT ALONG THE IL/WI BORDER THROUGH MONDAY MORNING.
ON MONDAY...LOW PRESSURE DEVELOPS ACROSS THE HIGH PLAINS IN
RESPONSE TO A SERIES OF MINOR SHORT WAVES AND JET ENERGY EMANATING
FROM AN UPPER TROUGH ALONG THE WEST COAST. TO OUR
SOUTH...EXTENSIVE AREA OF HIGH PRESSURE FROM THE ARKLATEX TO THE
CAROLINAS MOVES OFF TO THE EAST AND LOW LEVEL FLOW OFF OF THE
WESTERN GULF BEGINS TO ADVECT NORTHWARD ACROSS THE PLAINS AND
MISSISSIPPI VALLEY. LOCALLY... FORECAST SOUNDINGS DEPICT LOW LEVEL
MOISTENING DURING THE AFTERNOON AND EVENING HOURS OF MONDAY WITH
SOME LIGHT QPF BEING GENERATED. THIS MAY RESULT IN SOME LIGHT
RAIN/DRIZZLE MONDAY AFTERNOON ESPECIALLY ACROSS SOUTHERN AND
WESTERN PARTS OF THE CWA. RAIN CHANCES WILL INCREASE MONDAY NIGHT
HOWEVER...AS SURFACE WAVE MOVES INTO THE MISSOURI VALLEY AND
MODEST LOW LEVEL JET AHEAD OF IT INCREASES MOISTURE TRANSPORT INTO
THE REGION. COINCIDENT WITH THIS...FRONT TO OUR NORTH DEVELOPS
SOUTH INTO IL/IN AHEAD OF APPROACHING SURFACE WAVE. TIGHTENING LOW
LEVEL BAROCLINIC ZONE WILL BECOME FOCUS FOR LIFT MONDAY NIGHT AS
WAVE APPROACHES WITH ASSOCIATED INCREASE IN POPS. STEEP LAPSE
RATES OF 7-8.0 C/KM IN FORECAST SOUNDINGS INDICATE THUNDER
POTENTIAL FOR MONDAY NIGHT. RAIN AND OCCASIONAL THUNDER POTENTIAL
LINGER TUESDAY AS THE FRONTAL WAVE MOVES TOWARD THE LOWER OHIO
VALLEY AND SLOWLY WEAKENS.
RATZER
&&
.LONG TERM...
417 AM CDT
WEDNESDAY THROUGH SATURDAY...
WEAKENING SURFACE WAVE TRACKS THROUGH OHIO VALLEY WEDNESDAY...
WITH FRONT SAGGING SOUTH ACROSS CENTRAL IL/IN BEHIND IT. AFTER
SOME LINGERING MORNING SHOWERS...IT APPEARS WEAK SHORT WAVE
RIDGING AND COOL LOW LEVEL NORTHEAST FLOW WILL LIMIT RAIN CHANCES
DURING THE MIDDAY AND AFTERNOON HOURS...PROBABLY THE BEST CHANCE
OF DRY WEATHER THROUGH FRIDAY. WEDNESDAY NIGHT SEES A RENEWED PUSH
OF WARM ADVECTION ABOVE THE FRONTAL ZONE AS ANOTHER SHORT WAVE
RIPPLES THROUGH WEST-SOUTHWEST FLOW ALOFT.
THURSDAY-FRIDAY THE MAIN UPPER TROUGH/CLOSED LOW INITIALLY ALONG
THE WEST COAST MOVES INLAND...WITH A JET STREAK ROUNDING THE BASE
AND DEEPENING THE SYSTEM OVER THE CENTRAL ROCKIES WEDNESDAY NIGHT
AND SURFACE CYCLOGENESIS OCCURRING OVER THE HIGH PLAINS. THIS
DEEPENING SYSTEM MOVES TO THE MID-MISSOURI VALLEY BY LATE THURSDAY
WITH THE FRONT ACROSS IL/IN LIFTING BACK NORTH AS A WARM FRONT.
THE POTENTIAL EXISTS FOR SEVERE WEATHER DURING THIS TIME WITH
STRONG DEEP LAYER SHEAR AND INCREASING INSTABILITY IN WARM/MOIST
WARM SECTOR AIR MASS ALONG/SOUTH OF THE WARM FRONT. SPC DAY 4
OUTLOOK DOES INCLUDE MUCH OF THE AREA IN A RISK FOR SEVERE
WEATHER. PERIODS OF SHOWERS/THUNDERSTORMS APPEAR LIKELY THROUGH
FRIDAY MORNING AS THE LOW OCCLUDES AND EVENTUALLY LIFTS INTO THE
UPPER MISSISSIPPI VALLEY ON FRIDAY. GFS AND ECMWF RUNS BOTH
INDICATE THE OCCLUDED FRONT LIFTING NORTHEAST ACROSS THE AREA
FRIDAY...WITH DRIER AIR MOVING IN BEHIND IT AND DIMINISHING PRECIP
CHANCES INTO FRIDAY NIGHT AND SATURDAY. WITH FRONT STRETCHED WEST-
EAST ACROSS CWA...LARGE TEMPERATURE GRADIENT MAKES DAILY TEMP
FORECAST DIFFICULT. WILL LIKELY SEE A LARGE RANGE FROM 40S/50S
NORTH WHERE NORTHEAST FLOW OFF THE LAKES OCCURS...TO THE 70S SOUTH
OF THE FRONT ACROSS CENTRAL IL/IN INCLUDING SOUTHERN CWA.
RATZER
&&
.FIRE WEATHER...
455 AM CDT
THE FIRE WEATHER WATCH HAS BEEN CANCELLED FOR TODAY.
DRY...MILD AND BREEZY CONDITIONS ARE ANTICIPATED ACROSS THE AREA
AGAIN TODAY. HOWEVER...RED FLAG WARNING CRITERIA IS NOT EXPECTED
TO BE MET.
AFTERNOON RELATIVE HUMIDITY VALUES ARE EXPECTED TO FALL TO THE 20
TO 25 PERCENT RANGE...WITH TEMPERATURES TOPPING OUT IN THE MID TO
UPPER 60S AND DEW POINTS MIXING OUT TO THE UPPER 20S TO AROUND 30
DEGREES. HOWEVER...WHILE SOUTHWEST WINDS MAY GUST AROUND 25 MPH BY
LATE THIS MORNING...WINDS ARE EXPECTED TO DIMINISH THIS AFTERNOON
DURING THE TIME OF LOWEST RELATIVE HUMIDITY...AND SUSTAINED 20
FOOT WINDS ARE EXPECTED TO REMAIN BELOW 20 MPH THROUGH THE DAY.
SINCE CONDITIONS ARE NOT EXPECTED TO DETERIORATE TO CRITICAL RED
FLAG CRITERIA...THE FIRE WEATHER WATCH HAS BEEN CANCELLED.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* LOW LEVEL WIND SHEAR THIS MORNING.
* STRONG/GUSTY SOUTHWEST WINDS THRU MID AFTERNOON. CMS
//DISCUSSION...UPDATED 12Z...
SOUTHWESTERLY WINDS WILL STEADILY INCREASE THIS MORNING WITH GUSTS
AS HIGH AS THE MID 20 KT RANGE AS STRONGER WINDS ALOFT BEGIN TO
MIX TO THE SURFACE. HOWEVER...THESE STRONGER WINDS ALOFT WILL
SLOWLY DIMINISH INTO THIS AFTERNOON. THUS EXPECTING PREVAILING
WINDS/GUSTS TO ALSO SLOWLY DIMINISH INTO THE AFTERNOON. WINDS WILL
TURN MORE SOUTHERLY AFTER SUNSET AND REMAIN SOUTHERLY INTO MONDAY
MORNING WITH SPEEDS GENERALLY BELOW 10 KT.
MID CLOUDS WILL CONTINUE TO MOVE ACROSS THE AREA THIS MORNING
WITH SOME HIGH BASED CU POSSIBLE THIS AFTERNOON. INCREASING HIGH
CLOUDS THIS EVENING LOWERING TO A MID DECK MONDAY MORNING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM FOR LOW LEVEL WIND SHEAR THIS MORNING.
* MEDIUM FOR WINDS THRU THE PERIOD. CMS
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
* MONDAY NIGHT AND TUESDAY...SHRA/TSRA. IFR/LIFR. NORTHEAST WINDS.
* WEDNESDAY...IFR/LIFR. CHANCE OF DRIZZLE. EAST WINDS.
* WEDNESAY NIGHT THROUGH THURSDAY NIGHT...SHRA/TSRA. IFR/LIFR.
EAST WINDS.
* FRIDAY...CHANCE OF SHRA. MVFR POSSIBLE. SOUTHWEST WINDS.
* SATURDAY...DRY/VFR. GUSTY WEST WINDS.
&&
.MARINE...
323 AM...A FRONTAL BOUNDARY WILL SAG ACROSS THE SOUTH CENTRAL
PORTIONS OF THE LAKE THIS AFTERNOON AND REMAIN THERE THROUGH
MONDAY MORNING...BEFORE FINALLY MOVING JUST SOUTH OF THE LAKE BY
MONDAY EVENING. THE FRONT IS THEN EXPECTED TO REMAIN GENERALLY
STATIONARY THRU MID WEEK AS LOW PRESSURE MOVES ALONG THE FRONT
TUESDAY NIGHT. THIS WILL TIGHTEN THE GRADIENT WITH 30 KTS POSSIBLE
MONDAY NIGHT INTO TUESDAY...MAINLY ACROSS THE NORTH HALF/NORTH TWO
THIRDS OF THE LAKE. A STRONG LOW IS EXPECTED TO MOVE ACROSS THE
WESTERN LAKES FRIDAY INTO SATURDAY. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
613 AM CDT Sun Apr 5 2015
.SHORT TERM...(Today)
ISSUED AT 254 AM CDT SUN APR 5 2015
Latest surface analysis showing high pressure over south central
Kentucky with the coldest temperatures, upper 20s to lower 30s,
located near the large fair weather system. Meanwhile, a frontal
boundary was located over northern Iowa eastward through extreme
southern Wisconsin with a band of showers occurring mainly north of
the boundary. The last few satellite loops indicating some patchy
mid clouds spilling east across the region this morning but most of
the forecast soundings and time height cross sections continue to
suggest the bulk of the more extensive cloud cover today will remain
to our north. Forecast soundings off the HRRR and Rapid Refresh
depicting another well mixed boundary layer again today which should
result in temperatures at or above guid values, and with the deep
mixing occurring this afternoon, rather low relative humidities and
gusty southwest winds.
&&
.LONG TERM...(Tonight through Saturday)
ISSUED AT 254 AM CDT SUN APR 5 2015
Position of frontal boundary will remain a significant challenge
much of the week. General philosophy remains the same as the
previous model runs, although with a bit of a slower southward push
late Tuesday. Because of that, bumped up high temperatures a few
degrees. Much of the model guidance shows upper 70s across the
southwest CWA Tuesday afternoon, although the far north is expected
to be about 10 degrees cooler with the front much closer.
Temperatures will generally be in the 60s Wednesday with some lower
70s south, as the front drops to near the I-70 corridor before
heading back north. Also warmed Thursday highs with mid-upper 70s
common.
With much of the week featuring rain chances, have tried to do some
refining of potential dry periods. With the atmosphere remaining
capped much of Monday, have scaled back PoP`s to mainly the
afternoon, and featured generally slight chances except far
northwest and far southeast. Monday night, have continued the likely
PoP`s most areas, as thunderstorms expand along the frontal boundary
just to our north. However, the precipitation threat will diminish
from south to north as capping becomes more prominent in the warm
sector.
With the front sagging southward, it currently appears Wednesday
should be dry over much of the area north of I-72, but PoP`s ramp up
again quickly as developing low pressure over the central Plains
drags the front northward once again. A closed upper low, which will
develop after a wave moves onshore Tuesday, continues to be a
pivotal player in the ultimate evolution of this front/low. The
longer range models are coming into closer agreement, although the
GFS remains on a faster track (ECMWF still has it over northwest
Wisconsin by Saturday morning, while the GFS is over Lake Huron).
Thursday remains the most unstable period, with the GFS-progged
CAPE`s approaching 2000 J/kg in the afternoon, although 0-6km bulk
shear values expected to be low, favoring more of a hail/wind severe
potential.
With the upper low remaining rather prominent late in the week, the
corresponding surface cyclone will be wrapping up, with a prominent
dry slot punching through on Friday. Have maintained some low chance
PoP`s on Friday, although this would mainly be in across the eastern
eastern CWA during the morning. With breezy southwest winds and
clearing skies, temperatures are still expected to reach near 70.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
ISSUED AT 610 AM CDT SUN APR 5 2015
VFR conditions are expected through tonight. High pressure off to
our southeast was producing a broad southwest flow across the region
early this morning. A frontal boundary to our north has produced
some scattered to broken mid clouds which have affected our northern
TAF sites early this morning. Those should push off to our east this
morning with some sct-bkn cirrus moving in for the remainder of the
day. Models indicating moisture will increase at all levels tonight
so we should see more clouds, especially later tonight when forecast
soundings suggest a band of low VFR or possibly MVFR cigs will track
from south to north across the TAF sites mainly after 06z. Surface
winds will be gusty out of the south to southwest today with prevailing
speeds of 12 to 17 kts with a few gusts up to 25 kts possible later
this morning through the mid afternoon hours before we see winds start
to decrease out of the south this evening to around 10 kts.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Smith
LONG TERM...Geelhart
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
323 AM CDT SUN APR 5 2015
.SHORT TERM...
244 PM CDT
THROUGH MONDAY...
ABUNDANT SUNSHINE THIS AFTERNOON WITH TEMPS WARMING INTO THE 50S
ACROSS MUCH OF THE AREA. UNFORTUNATELY THE MAIN CONCERN HAS BEEN
ON HOW DRY IT HAS BECOME WITH THE DEW POINTS IN THE LOW 20S...AND
GUSTY WEST WINDS THIS AFTN. RELATIVE HUMIDITY VALUES HAVE FALLEN
TO NEAR RED FLAG CONDITIONS. AS SUNSET APPROACHES...TEMPS WILL
START TO COOL AND ALLOW HUMIDITY VALUES TO SLOWLY RISE AND GUSTY
WINDS WILL DECOUPLE. THE SFC RIDGE HAS BECOME CENTERED ACORSS THE
WESTERN TENN VALLEY...WITH THE PRESSURE GRADIENT ORIENTED WEST TO
EAST ACROSS THE FORECAST AREA.
THE SFC RIDGE WILL BEGIN TO DRIFT SOUTHEAST TONIGHT...ALLOWING WINDS
TO TURN SOUTHWESTERLY. MEANWHILE A CANADIAN SFC RIDGE WILL NUDGE
SOUTH...WITH A FRONTAL BOUNDARY DROPPING SOUTH ACROSS THE UPPER
MIDWEST INTO THE WESTERN GREAT LAKES. THE FLOW LOOKS TO REMAIN
STRONG ENOUGH FROM THE SOUTH TO PREVENT THIS BOUNDARY FROM DIPPING
INTO NORTHERN IL UNTIL MON. GUIDANCE CONTINUES TO KEEP MUCH OF THE
CLOUD COVER NORTH ALONG THE BOUNDARY TONIGHT...ALONG WITH A SERIES
OF WEAK WAVES RIDING THE BOUNDARY. MOISTURE WILL POOL ALONG THE
FRONT TONIGHT...AND PERSIST THROUGH SUNDAY. BUT AGAIN SHOULD REMAIN
WELL NORTH OF NORTHERN IL.
TEMPS TONIGHT WILL RADIATE INTO THE UPR 30S TO LOW 40S NEAR DOWNTOWN
CHICAGO.
SUNDAY THROUGH MONDAY... MAIN CONCERN FOR SUN WILL BE ON POTENTIAL
TO REACH RED FLAG CONDITIONS. SFC RIDGE WILL BE ORIENTED TO THE
SOUTHEAST OF THE CWFA...WITH FLOW TURNING SOUTHWESTERLY. LLVL
MOISTURE REMAINS WELL SOUTH OF THE REGION...HOWEVER GUIDANCE IS
INDICATING THAT SOME MOISTURE WILL NUDGE DEW POINTS UP A COUPLE
DEGREES INTO THE MID/UPR 20S. THAT COMBINED WITH SFC TEMPS POISED TO
WARM INTO THE MID 60S...WILL LIKELY PRODUCE RELATIVE HUMIDITY VALUES
IN THE LOW/MID 20 PERCENT RANGE SUN LATE MORNING THROUGH MID-
AFTERNOON.
500MB TROUGH WILL BE DIGGING INTO THE SOUTHWEST CONUS SUN NGT...WITH
A SFC WAVE DEVELOPING ACROSS THE LEE-SIDE OF THE ROCKIES. THIS
SHOULD HELP IN KEEPING THE SFC BOUNDARY JUST NORTH OF THE FORECAST
AREA SUN NGT ALONG WITH FLOW TURNING MORE SOUTHERLY AHEAD OF THE
WAVE. LLVL MOISTURE WILL CONTINUE TO INCREASE...WITH THE WESTERN
GULF FEEDING MOISTURE NORTH. PRECIP LOOKS TO REMAIN SOUTH AND NORTH
THROUGH SUN NGT...AND DEPENDING ON HOW LONG THE DIFFLUENCE FLOW IN
THE MID-LVLS REMAINS MON COULD ALSO BE DRY. AT THIS POINT WILL HOLD
INTO THE MENTION OF SLT CHC POPS. TEMPS MON WILL LIKELY AGAIN TOUCH
THE MID/UPR 50S...AND POSSIBLY THE LOW 60S IN THE FAR SOUTH.
BEACHLER
&&
.LONG TERM...
229 PM CDT
MONDAY NIGHT THROUGH SATURDAY...
THE MAIN CONCERNS DURING THE PERIOD WILL BE TIMING OF SHOWER AND
THUNDERSTORM CHANCES...THE POTENTIAL FOR A PERIOD OF STRONG TO
SEVERE STORMS...AND TEMPERATURES THROUGH THE WEEK AS WE HEAD INTO A
VERY ACTIVE WEATHER PATTERN.
A VERY ACTIVE PERIOD OF WEATHER STILL LOOKS ON TAP FOR THE MUCH OF
THE UPCOMING WEEK AS A SURFACE FRONTAL BOUNDARY BECOMES QUASI-
STATIONARY RIGHT ACROSS THE REGION. SEVERAL MID-LEVEL DISTURBANCES
ARE EXPECTED TO EJECT EASTWARD OUT OF THE SOUTHWESTERN CONUS UPPER
TROUGH...AND EACH OF THESE WILL LIKELY DRIVE SURFACE WAVES EASTWARD
ALONG THE SURFACE FRONTAL ZONE. AS SUCH...ALTHOUGH THERE ARE VERY
GOOD CHANCES OF SHOWERS AND STORMS THROUGH THE PERIOD...IT WILL NOT
BE RAINING CONSTANTLY. INSTEAD...THE BEST CHANCES OF PRECIPITATION
WILL BE TIED TO THE TIMING OF EACH OF THESE WAVES OF ENERGY.
AT THE START OF THE PERIOD ON MONDAY NIGHT THE FRONTAL BOUNDARY IS
FORECAST TO SHIFT ACROSS NORTHERN ILLINOIS BEFORE STALLING OUT
ACROSS CENTRAL ILLINOIS BY TUESDAY MORNING. IT STILL APPEARS THAT
THE FIRST WAVE OF SHOWERS AND THUNDERSTORMS WILL IMPACT THE AREA
MONDAY NIGHT AS THE FIRST GOOD PUSH OF MOISTURE OCCURS AHEAD OF THE
FIRST APPROACHING WAVE. MODEL SOUNDINGS INDICATE THAT MID-LEVEL
LAPSE RATES WILL BE FAIRY STEEP (E.G., AROUND 7 DEG C/KM)...SO SOME
ELEVATED THUNDERSTORMS APPEAR TO BE A DECENT BET WITH THIS ACTIVITY.
ANOTHER WAVE OF ACTIVITY IS ALSO LIKELY LATE TUESDAY INTO TUESDAY
NIGHT.
WEDNESDAY STILL APPEARS TO BE A MAINLY DRY DAY ACROSS THE REGION AS
WE END UP WAITING FOR THE NEXT WAVE OF ENERGY TO APPROACH THE AREA
WEDNESDAY NIGHT INTO THURSDAY. UNCERTAINTY INCREASES WITH THE TIMING
OF THE EJECTION OF THE MAIN SOUTHWESTERN TROUGH OVER THE CENTRAL
CONUS LATE IN THE PERIOD AS ENSEMBLE SOLUTIONS DIVERGE WITH THE
TIMING IN A HURRY THURSDAY AND FRIDAY. HOWEVER...AS THE MAIN SYSTEM
DOES BEGIN TO SHIFT EASTWARD OVER THE CENTRAL CONUS...IT COULD END
UP RESULTING IN A PERIOD OF STRONG CONVECTIVE ACTIVITY OVER...OR
NEAR THE REGION LATER IN THE WEEK. DEEP LAYER SHEAR WOULD CERTAINLY
BE CONDUCIVE TO SUPPORT STRONG CONVECTION IF THE WARM SECTOR OF THE
STORM SYSTEM DOES GET ACROSS NORTHERN ILLINOIS. AT THIS TIME...THERE
ARE STILL LARGE UNCERTAINTIES IN HOW THIS LATER WEEK SYSTEM WILL
EVOLVE...AND HENCE HOW FOR NORTH THE WARM SECTOR MAY GET. IN SPITE
OF THESE UNCERTAINTIES...HOWEVER...THE THURSDAY THROUGH FRIDAY
TIMEFRAME WILL NEED TO BE WATCHED FOR THE POTENTIAL OF STRONG OR
SEVERE STORMS NEAR THE AREA. GOOD AMOUNTS OF RAINFALL ARE ALSO
POSSIBLE ACROSS THE AREA WITH THE POSSIBILITY OF BETTER DEEP
MOISTURE.
TEMPERATURES DURING THE PERIOD WILL BE MILD SOUTH AND COOL
NORTH...ESPECIALLY NEAR LAKE MICHIGAN DUE TO THE PROLONGED ONSHORE
FLOW PATTERN.
KJB
&&
.FIRE WEATHER...
244 PM CDT
GUSTY WEST WINDS BETWEEN 25 AND 35 MPH HAS ALLOWED STRONG MIXING
TO OCCUR AND PUSH RELATIVE HUMIDITY VALUES DOWN TO THE MIDDLE TO
UPPER 20 PERCENT RANGE. A FEW LOCATIONS HAVE OBSERVED BORDERLINE
RED FLAG CONDITIONS WITH RELATIVE HUMIDITY VALUES AROUND 20
PERCENT THIS AFTERNOON. WINDS WILL EVENTUALLY DECOUPLE AROUND
SUNSET OR SHORTLY AFTER...THEN RETURN SUNDAY. WHILE WINDS WILL BE
TURNING SOUTHWESTERLY SUNDAY...WIND GUSTS LATE SUNDAY MORNING
THROUGH MID AFTERNOON WILL AGAIN BE 25 TO 35 MPH. THIS COUPLED
WITH DEW POINTS REMAINING IN THE MIDDLE TO UPPER 20S WILL PRODUCE
RELATIVE HUMIDITY VALUES BETWEEN 25 AND 30 PERCENT. THERE REMAINS
SOME UNCERTAINTY FOR SUNDAY ON DEW POINTS...AS IT IS POSSIBLE DEW
POINTS MAY BE HOLDING IN THE UPPER 20S TO AROUND 30. THIS WOULD
KEEP RELATIVE HUMIDITY VALUES CLSOER TO 30 PERCENT.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* LOW LEVEL WIND SHEAR EARLY THIS MORNING.
* STRONG/GUSTY SOUTHWEST WINDS AFTER SUNRISE THRU MID AFTERNOON.
CMS
//DISCUSSION...UPDATED 06Z...
SOUTHWESTERLY WINDS WILL REMAIN IN THE 10-14KT RANGE EARLY THIS
MORNING WITH SOME HIGHER GUSTS POSSIBLE AS THE GRADIENT REMAINS
FAIRLY TIGHT. ALOFT...VERY STRONG WINDS OF 40-50KT WILL CAUSE LOW
LEVEL WIND SHEAR THROUGH 2KFT. THESE WINDS WILL START TO DIMINISH
IN SPEED AFTER SUNRISE. AS THE LOW LEVELS BEGIN TO MIX AFTER
SUNRISE...SOME OF THESE HIGHER WINDS WILL MIX DOWN WITH GUSTS INTO
THE MID/UPPER 20 KT RANGE POSSIBLE. BUT THESE WINDS ALOFT WILL
CONTINUE TO SLOWLY DIMINISH INTO THIS AFTERNOON AND EXPECT SURFACE
WINDS/GUSTS TO ALSO SLOWLY DIMINISH THIS AFTERNOON...TURNING BACK
SOUTHERLY AT OR BELOW 10 KT AFTER SUNSET.
MID CLOUDS WILL CONTINUE TO MOVE ACROSS THE REGION THROUGH LATE
MORNING WITH SOME HIGH BASED CU POSSIBLE THIS AFTERNOON THEN HIGH
CLOUDS TONIGHT. CMS
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* MEDIUM FOR LOW LEVEL WIND SHEAR EARLY THIS MORNING.
* MEDIUM FOR WINDS THRU THE PERIOD. CMS
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR. SOUTH WINDS PROBABLE...CHANCE OF WIND SHIFT TO E/NE.
CHANCE OF SHRA/TSRA AT NIGHT.
TUESDAY THROUGH WEDNESDAY...IFR/LIFR CIGS. STRONG NE WINDS. OCNL
DZ/FG...CHANCE -RA.
THURSDAY THROUGH FRIDAY...PERIODS OF SHRA/TSRA.
IZZI
&&
.MARINE...
323 AM...A FRONTAL BOUNDARY WILL SAG ACROSS THE SOUTH CENTRAL
PORTIONS OF THE LAKE THIS AFTERNOON AND REMAIN THERE THROUGH
MONDAY MORNING...BEFORE FINALLY MOVING JUST SOUTH OF THE LAKE BY
MONDAY EVENING. THE FRONT IS THEN EXPECTED TO REMAIN GENERALLY
STATIONARY THRU MID WEEK AS LOW PRESSURE MOVES ALONG THE FRONT
TUESDAY NIGHT. THIS WILL TIGHTEN THE GRADIENT WITH 30 KTS POSSIBLE
MONDAY NIGHT INTO TUESDAY...MAINLY ACROSS THE NORTH HALF/NORTH TWO
THIRDS OF THE LAKE. A STRONG LOW IS EXPECTED TO MOVE ACROSS THE
WESTERN LAKES FRIDAY INTO SATURDAY. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FIRE WEATHER WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039...11 AM SUNDAY TO 8 PM SUNDAY.
IN...FIRE WEATHER WATCH...INZ001-INZ002-INZ010-INZ011-INZ019...11 AM
SUNDAY TO 8 PM SUNDAY.
LM...NONE.
&&
$$
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
254 AM CDT Sun Apr 5 2015
.SHORT TERM...(Today)
ISSUED AT 254 AM CDT SUN APR 5 2015
Latest surface analysis showing high pressure over south central
Kentucky with the coldest temperatures, upper 20s to lower 30s,
located near the large fair weather system. Meanwhile, a frontal
boundary was located over northern Iowa eastward through extreme
southern Wisconsin with a band of showers occurring mainly north of
the boundary. The last few satellite loops indicating some patchy
mid clouds spilling east across the region this morning but most of
the forecast soundings and time height cross sections continue to
suggest the bulk of the more extensive cloud cover today will remain
to our north. Forecast soundings off the HRRR and Rapid Refresh
depicting another well mixed boundary layer again today which should
result in temperatures at or above guid values, and with the deep
mixing occurring this afternoon, rather low relative humidities and
gusty southwest winds.
&&
.LONG TERM...(Tonight through Saturday)
ISSUED AT 254 AM CDT SUN APR 5 2015
Position of frontal boundary will remain a significant challenge
much of the week. General philosophy remains the same as the
previous model runs, although with a bit of a slower southward push
late Tuesday. Because of that, bumped up high temperatures a few
degrees. Much of the model guidance shows upper 70s across the
southwest CWA Tuesday afternoon, although the far north is expected
to be about 10 degrees cooler with the front much closer.
Temperatures will generally be in the 60s Wednesday with some lower
70s south, as the front drops to near the I-70 corridor before
heading back north. Also warmed Thursday highs with mid-upper 70s
common.
With much of the week featuring rain chances, have tried to do some
refining of potential dry periods. With the atmosphere remaining
capped much of Monday, have scaled back PoP`s to mainly the
afternoon, and featured generally slight chances except far
northwest and far southeast. Monday night, have continued the likely
PoP`s most areas, as thunderstorms expand along the frontal boundary
just to our north. However, the precipitation threat will diminish
from south to north as capping becomes more prominent in the warm
sector.
With the front sagging southward, it currently appears Wednesday
should be dry over much of the area north of I-72, but PoP`s ramp up
again quickly as developing low pressure over the central Plains
drags the front northward once again. A closed upper low, which will
develop after a wave moves onshore Tuesday, continues to be a
pivotal player in the ultimate evolution of this front/low. The
longer range models are coming into closer agreement, although the
GFS remains on a faster track (ECMWF still has it over northwest
Wisconsin by Saturday morning, while the GFS is over Lake Huron).
Thursday remains the most unstable period, with the GFS-progged
CAPE`s approaching 2000 J/kg in the afternoon, although 0-6km bulk
shear values expected to be low, favoring more of a hail/wind severe
potential.
With the upper low remaining rather prominent late in the week, the
corresponding surface cyclone will be wrapping up, with a prominent
dry slot punching through on Friday. Have maintained some low chance
PoP`s on Friday, although this would mainly be in across the eastern
eastern CWA during the morning. With breezy southwest winds and
clearing skies, temperatures are still expected to reach near 70.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 1145 PM CDT SAT APR 4 2015
VFR conditions will continue at all TAF sites next 24hrs. Skies
should remain clear to mostly clear most of the period, but some
high cirrus may advect over the sites tomorrow evening. Winds will
become more southwest to south through the period with gusts
around 20-24kts possible tomorrow. Winds will again diminish
tomorrow evening after sunset.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Smith
LONG TERM...Geelhart
AVIATION...Auten
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
121 PM EDT SUN APR 5 2015
.SYNOPSIS...
ISSUED AT 400 AM EDT SUN APR 5 2015
HIGH PRESSURE WILL SLIDE EAST TO THE MID ATLANTIC COAST BY THIS
EVENING BUT IT WILL STILL BE STRONG ENOUGH TO PROVIDE MOSTLY
CLEAR SKIES AND DRY CONDITIONS FOR OUR AREA. CLOUDS WILL INCREASE
LATE TONIGHT AS A WEAK FRONT MOVES INTO THE REGION FROM THE NORTH
WHILE MOISTURE INCREASES FROM THE SOUTH. HIGH TEMPERATURES TODAY
WILL BE IN THE LOW TO MID 60S. LOWS TONIGHT WILL RANGE FROM THE
UPPER 30S IN MICHIGAN TO THE MIDDLE 40S OVER CENTRAL INDIANA AND
OHIO.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 353 AM EDT SUN APR 5 2015
MID LEVEL CLOUDS INCREASING THIS MORNING AS A FRONTAL WAVE SLIDES BY
THROUGH MICHIGAN. THIS FRONT NORTH OF OUR AREA WILL HAVE LITTLE
IMPACT ON OUR SENSIBLE WEATHER OTHER THAN A SCATTERED MID LEVEL
CLOUD DECK THROUGH THE DAY SUNDAY. EXPECT ANY CLOUDINESS OVER OUR
AREA TO BE THIN ENOUGH THAT IT WILL DO LITTLE TO LIMIT AFTERNOON
THERMAL MIXING ACROSS THE CWA. TEMPERATURES HAVE CONSISTENTLY
OUTPERFORMED GUIDANCE SO FAR THIS SPRING WITH FULL SUN AND DEEP
MIXING...THEREFORE MIXING TO AT LEAST 850MB AGAIN ON SUNDAY PER
BUFKIT SOUNDINGS AND MOSTLY SUNNY SKIES WARRANTS A TREND TOWARDS THE
WARMEST GUIDANCE. 05Z RAP WAS AROUND 3 TO 4 DEGREES WARMER THAN THE
REST OF THE GUIDANCE...SO USED 05Z RAP FOR HIGHS AFTER KNOCKING IT
DOWN ONE DEGREE DUE TO THE POTENTIAL FOR SOME CLOUDINESS ACROSS THE
AREA.
WINDY CONDITIONS ARE ANTICIPATED AGAIN ON SUNDAY...ALTHOUGH GIVEN A
SLIGHTLY SHALLOWER MIXING DEPTH AND WEAKER SYNOPTIC WINDS EXPECT
WINDS TO BE WEAKER THAN SATURDAY... LIKELY IN THE 15 MPH RANGE WITH
GUSTS AROUND 25 MPH.
&&
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 353 AM EDT SUN APR 5 2015
MODELS CONTINUE TO ADVERTISE AN ACTIVE AND WET PATTERN DURING MOST
OF THE LONG TERM PERIOD. NO REASON TO DOUBT WITH QUASI STATIONARY
BOUNDARY IN THE REGION BUT QUESTIONS DO CONTINUE WITH TIMING OF
WAVES AND LOCATION OF BOUNDARY.
MOISTURE ADVECTION WILL BE UNDERWAY MONDAY WITH PWATS CREEPING
TOWARD ONE INCH AND THETA E RIDGE NOSING INTO THE AREA. WEAK FRONTAL
BOUNDARY WILL BE SAGGING INTO THE AREA AS MOISTURE INCREASES BUT NO
STRONG FORCING. MODELS INDICATING SOME POSSIBLE LIGHT SHOWERS BY
AFTERNOON SO WILL CONTINUE WITH LOW CHANCE POPS.
RAIN CHANCES STILL LOOK BEST MONDAY NIGHT INTO TUESDAY WITH FIRST
SHORT WAVE AND ASSOCIATED LOW PRESSURE RIDING BOUNDARY. BEYOND
THIS...CONFIDENCE REMAINS ON LOW SIDE WITH TIMING ANY PCPN CHANCES
ACROSS THE AREA. THERE IS AGREEMENT THAT FRONT WILL PUSH FAR ENOUGH
SOUTH AFTER FIRST WAVE THAT WE MAY SEE A PERIOD OF DRY WEATHER
WEDNESDAY BEFORE NEXT SHORT WAVE AND WARM FRONT MOVES THROUGH
THURSDAY. RELUCTANTLY STAYED WITH BLENDED INIT OF LIKELY POPS FOR
COLLABORATION PURPOSES WITH CONCERNS OVER CONVECTIVE INFLUENCES THAT
HAVE YET TO BE MODELED. MAIN COLD FRONT THEN LOOKS TO PUSH THROUGH
LATE THURSDAY NIGHT OR FRIDAY DEPENDING ON MODEL OF CHOICE.
CONTINUED WITH BLENDED SOLUTIONS AND CONSISTENCY FOR NOW WITH MODEL
CHANGES EXPECTED THROUGH THE WEEK.
THERE IS A POSSIBILITY OF SEVERE WEATHER GIVEN STRENGTH OF A COUPLE
WAVES BUT NARROWING DOWN STILL DIFFICULT. WOULD LEAN TOWARD WARM
FRONTAL PUSH THURSDAY THEN MAIN COLD FRONT PASSAGE LATE THURSDAY
NIGHT OR FRIDAY. CERTAINLY WORTH WATCHING NEXT FEW DAYS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 116 PM EDT SUN APR 5 2015
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. SW WINDS IN 15-25KT
RANGE SHOULD CONT THIS AFTN... DIMINISHING QUICKLY THIS EVE WITH
LOSS OF HEATING/MIXING. A WK SHRTWV OVER THE CENTRAL PLAINS WILL
MOVE THROUGH THE AREA MONDAY MORNING BRINGING AN INCREASE IN MID
CLOUDS. PERSISTENT S-SW FLOW SHOULD ALSO BRING INCREASED LOW LEVEL
MOISTURE INTO THE AREA DURING THE DAY RESULTING IN LOWER CIGS BY
THE END OF THE PERIOD... BUT PRBLY STILL ABOVE MVFR.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...LASHLEY
SHORT TERM...BENTLEY
LONG TERM...LASHLEY
AVIATION...JT
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
634 AM EDT SUN APR 5 2015
.SYNOPSIS...
ISSUED AT 400 AM EDT SUN APR 5 2015
HIGH PRESSURE WILL SLIDE EAST TO THE MID ATLANTIC COAST BY THIS
EVENING BUT IT WILL STILL BE STRONG ENOUGH TO PROVIDE MOSTLY
CLEAR SKIES AND DRY CONDITIONS FOR OUR AREA. CLOUDS WILL INCREASE
LATE TONIGHT AS A WEAK FRONT MOVES INTO THE REGION FROM THE NORTH
WHILE MOISTURE INCREASES FROM THE SOUTH. HIGH TEMPERATURES TODAY
WILL BE IN THE LOW TO MID 60S. LOWS TONIGHT WILL RANGE FROM THE
UPPER 30S IN MICHIGAN TO THE MIDDLE 40S OVER CENTRAL INDIANA AND
OHIO.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 353 AM EDT SUN APR 5 2015
MID LEVEL CLOUDS INCREASING THIS MORNING AS A FRONTAL WAVE SLIDES BY
THROUGH MICHIGAN. THIS FRONT NORTH OF OUR AREA WILL HAVE LITTLE
IMPACT ON OUR SENSIBLE WEATHER OTHER THAN A SCATTERED MID LEVEL
CLOUD DECK THROUGH THE DAY SUNDAY. EXPECT ANY CLOUDINESS OVER OUR
AREA TO BE THIN ENOUGH THAT IT WILL DO LITTLE TO LIMIT AFTERNOON
THERMAL MIXING ACROSS THE CWA. TEMPERATURES HAVE CONSISTENTLY
OUTPERFORMED GUIDANCE SO FAR THIS SPRING WITH FULL SUN AND DEEP
MIXING...THEREFORE MIXING TO AT LEAST 850MB AGAIN ON SUNDAY PER
BUFKIT SOUNDINGS AND MOSTLY SUNNY SKIES WARRANTS A TREND TOWARDS THE
WARMEST GUIDANCE. 05Z RAP WAS AROUND 3 TO 4 DEGREES WARMER THAN THE
REST OF THE GUIDANCE...SO USED 05Z RAP FOR HIGHS AFTER KNOCKING IT
DOWN ONE DEGREE DUE TO THE POTENTIAL FOR SOME CLOUDINESS ACROSS THE
AREA.
WINDY CONDITIONS ARE ANTICIPATED AGAIN ON SUNDAY...ALTHOUGH GIVEN A
SLIGHTLY SHALLOWER MIXING DEPTH AND WEAKER SYNOPTIC WINDS EXPECT
WINDS TO BE WEAKER THAN SATURDAY... LIKELY IN THE 15 MPH RANGE WITH
GUSTS AROUND 25 MPH.
&&
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 353 AM EDT SUN APR 5 2015
MODELS CONTINUE TO ADVERTISE AN ACTIVE AND WET PATTERN DURING MOST
OF THE LONG TERM PERIOD. NO REASON TO DOUBT WITH QUASI STATIONARY
BOUNDARY IN THE REGION BUT QUESTIONS DO CONTINUE WITH TIMING OF
WAVES AND LOCATION OF BOUNDARY.
MOISTURE ADVECTION WILL BE UNDERWAY MONDAY WITH PWATS CREEPING
TOWARD ONE INCH AND THETA E RIDGE NOSING INTO THE AREA. WEAK FRONTAL
BOUNDARY WILL BE SAGGING INTO THE AREA AS MOISTURE INCREASES BUT NO
STRONG FORCING. MODELS INDICATING SOME POSSIBLE LIGHT SHOWERS BY
AFTERNOON SO WILL CONTINUE WITH LOW CHANCE POPS.
RAIN CHANCES STILL LOOK BEST MONDAY NIGHT INTO TUESDAY WITH FIRST
SHORT WAVE AND ASSOCIATED LOW PRESSURE RIDING BOUNDARY. BEYOND
THIS...CONFIDENCE REMAINS ON LOW SIDE WITH TIMING ANY PCPN CHANCES
ACROSS THE AREA. THERE IS AGREEMENT THAT FRONT WILL PUSH FAR ENOUGH
SOUTH AFTER FIRST WAVE THAT WE MAY SEE A PERIOD OF DRY WEATHER
WEDNESDAY BEFORE NEXT SHORT WAVE AND WARM FRONT MOVES THROUGH
THURSDAY. RELUCTANTLY STAYED WITH BLENDED INIT OF LIKELY POPS FOR
COLLABORATION PURPOSES WITH CONCERNS OVER CONVECTIVE INFLUENCES THAT
HAVE YET TO BE MODELED. MAIN COLD FRONT THEN LOOKS TO PUSH THROUGH
LATE THURSDAY NIGHT OR FRIDAY DEPENDING ON MODEL OF CHOICE.
CONTINUED WITH BLENDED SOLUTIONS AND CONSISTENCY FOR NOW WITH MODEL
CHANGES EXPECTED THROUGH THE WEEK.
THERE IS A POSSIBILITY OF SEVERE WEATHER GIVEN STRENGTH OF A COUPLE
WAVES BUT NARROWING DOWN STILL DIFFICULT. WOULD LEAN TOWARD WARM
FRONTAL PUSH THURSDAY THEN MAIN COLD FRONT PASSAGE LATE THURSDAY
NIGHT OR FRIDAY. CERTAINLY WORTH WATCHING NEXT FEW DAYS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 633 AM EDT SUN APR 5 2015
SIMILAR TO YESTERDAY IT WILL BE VFR BUT BREEZY WITH WINDS OF 10 TO
20 KNOTS AND GUSTS TO 25 KNOTS. HIGH CLOUDS TO INCREASE LATE
TONIGHT BUT STILL EXPECT VFR.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...LASHLEY
SHORT TERM...BENTLEY
LONG TERM...LASHLEY
AVIATION...LASHLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
406 AM EDT SUN APR 5 2015
.SYNOPSIS...
ISSUED AT 400 AM EDT SUN APR 5 2015
HIGH PRESSURE WILL SLIDE EAST TO THE MID ATLANTIC COAST BY THIS
EVENING BUT IT WILL STILL BE STRONG ENOUGH TO PROVIDE MOSTLY
CLEAR SKIES AND DRY CONDITIONS FOR OUR AREA. CLOUDS WILL INCREASE
LATE TONIGHT AS A WEAK FRONT MOVES INTO THE REGION FROM THE NORTH
WHILE MOISTURE INCREASES FROM THE SOUTH. HIGH TEMPERATURES TODAY
WILL BE IN THE LOW TO MID 60S. LOWS TONIGHT WILL RANGE FROM THE
UPPER 30S IN MICHIGAN TO THE MIDDLE 40S OVER CENTRAL INDIANA AND
OHIO.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 353 AM EDT SUN APR 5 2015
MID LEVEL CLOUDS INCREASING THIS MORNING AS A FRONTAL WAVE SLIDES BY
THROUGH MICHIGAN. THIS FRONT NORTH OF OUR AREA WILL HAVE LITTLE
IMPACT ON OUR SENSIBLE WEATHER OTHER THAN A SCATTERED MID LEVEL
CLOUD DECK THROUGH THE DAY SUNDAY. EXPECT ANY CLOUDINESS OVER OUR
AREA TO BE THIN ENOUGH THAT IT WILL DO LITTLE TO LIMIT AFTERNOON
THERMAL MIXING ACROSS THE CWA. TEMPERATURES HAVE CONSISTENTLY
OUTPERFORMED GUIDANCE SO FAR THIS SPRING WITH FULL SUN AND DEEP
MIXING...THEREFORE MIXING TO AT LEAST 850MB AGAIN ON SUNDAY PER
BUFKIT SOUNDINGS AND MOSTLY SUNNY SKIES WARRANTS A TREND TOWARDS THE
WARMEST GUIDANCE. 05Z RAP WAS AROUND 3 TO 4 DEGREES WARMER THAN THE
REST OF THE GUIDANCE...SO USED 05Z RAP FOR HIGHS AFTER KNOCKING IT
DOWN ONE DEGREE DUE TO THE POTENTIAL FOR SOME CLOUDINESS ACROSS THE
AREA.
WINDY CONDITIONS ARE ANTICIPATED AGAIN ON SUNDAY...ALTHOUGH GIVEN A
SLIGHTLY SHALLOWER MIXING DEPTH AND WEAKER SYNOPTIC WINDS EXPECT
WINDS TO BE WEAKER THAN SATURDAY... LIKELY IN THE 15 MPH RANGE WITH
GUSTS AROUND 25 MPH.
&&
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 353 AM EDT SUN APR 5 2015
MODELS CONTINUE TO ADVERTISE AN ACTIVE AND WET PATTERN DURING MOST
OF THE LONG TERM PERIOD. NO REASON TO DOUBT WITH QUASI STATIONARY
BOUNDARY IN THE REGION BUT QUESTIONS DO CONTINUE WITH TIMING OF
WAVES AND LOCATION OF BOUNDARY.
MOISTURE ADVECTION WILL BE UNDERWAY MONDAY WITH PWATS CREEPING
TOWARD ONE INCH AND THETA E RIDGE NOSING INTO THE AREA. WEAK FRONTAL
BOUNDARY WILL BE SAGGING INTO THE AREA AS MOISTURE INCREASES BUT NO
STRONG FORCING. MODELS INDICATING SOME POSSIBLE LIGHT SHOWERS BY
AFTERNOON SO WILL CONTINUE WITH LOW CHANCE POPS.
RAIN CHANCES STILL LOOK BEST MONDAY NIGHT INTO TUESDAY WITH FIRST
SHORT WAVE AND ASSOCIATED LOW PRESSURE RIDING BOUNDARY. BEYOND
THIS...CONFIDENCE REMAINS ON LOW SIDE WITH TIMING ANY PCPN CHANCES
ACROSS THE AREA. THERE IS AGREEMENT THAT FRONT WILL PUSH FAR ENOUGH
SOUTH AFTER FIRST WAVE THAT WE MAY SEE A PERIOD OF DRY WEATHER
WEDNESDAY BEFORE NEXT SHORT WAVE AND WARM FRONT MOVES THROUGH
THURSDAY. RELUCTANTLY STAYED WITH BLENDED INIT OF LIKELY POPS FOR
COLLABORATION PURPOSES WITH CONCERNS OVER CONVECTIVE INFLUENCES THAT
HAVE YET TO BE MODELED. MAIN COLD FRONT THEN LOOKS TO PUSH THROUGH
LATE THURSDAY NIGHT OR FRIDAY DEPENDING ON MODEL OF CHOICE.
CONTINUED WITH BLENDED SOLUTIONS AND CONSISTENCY FOR NOW WITH MODEL
CHANGES EXPECTED THROUGH THE WEEK.
THERE IS A POSSIBILITY OF SEVERE WEATHER GIVEN STRENGTH OF A COUPLE
WAVES BUT NARROWING DOWN STILL DIFFICULT. WOULD LEAN TOWARD WARM
FRONTAL PUSH THURSDAY THEN MAIN COLD FRONT PASSAGE LATE THURSDAY
NIGHT OR FRIDAY. CERTAINLY WORTH WATCHING NEXT FEW DAYS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 132 AM EDT SUN APR 5 2015
VFR CONDITIONS EXPECTED THROUGH THE PERIOD WITH GUSTY WINDS ON
SUNDAY THE ONLY IMPACT TO TAF SITES. WINDS WILL INCREASE WITH
DAYTIME HEATING ON SUNDAY...AND WANE AS TEMPERATURES COOL DURING
THE EVENING HOURS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...LASHLEY
SHORT TERM...BENTLEY
LONG TERM...LASHLEY
AVIATION...BENTLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
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AREA FORECAST DISCUSSION
NWS TOPEKA KS
647 PM CDT Mon Apr 6 2015
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Tuesday)
Issued at 359 PM CDT MON APR 6 2015
An amplified upper level trough off the northern CA coast will
slowly dig east-southeast across CA into western NV by late Monday
Afternoon. The southwesterly mid and upper level flow across the
plains will increase through the period with 45 to 50kt 500 mb winds
moving northeast across the state of KS by late Tuesday afternoon.
Tonight, southerly low-level winds will begin to advect deep Gulf
moisture north-northeast across the CWA. The ARW, RUC and NAM models
all show isentropic lift at the 300K level increasing across
northeast KS towards 6Z. The resulting lift may cause elevated
thunderstorms to develop, especially north of I-70 and east of a
Manhattan to Marysville line. The EML over spreading the area Today
will allow for steep lapse rates. The NAM and ARW models show
MUCAPES of 3,000 to 4,000 J/KG and Effective shear of 30 to 40 KTS
above the inversion across portions of east central and northeast KS
from 3Z to 9Z. Therefore some of the elevated thunderstorms may
produce large hail, especially if any of the elevated storms can
rotate at mid-levels. The elevated thunderstorms should move
northeast into IA and northern MO by 12Z.
Tuesday, a surface front will move southward across the CWA through
the day. The northern counties of the CWA may remain cloudy north
of the front. As the front moves southeastward into northeast and
east central KS, the front will encounter deeper gulf moisture and
the surface convergence will increase along the front through the
Afternoon hours. The NAM and ARW show a dryline punch advecting
northeast from south central KS towards EMP. The NAM forecast
soundings show the CAP at EMP nearly removed as temperatures will
warm into the mid 80s ahead the cold front across southern Lyon
county. The NAM model develops QPF across Osage county along the
front between 21 and 24Z TUE, while the ARW shows QPF developing
across Jefferson county ahead of the surface front. Since there is a
chance for the CAP to break along the front late Tuesday Afternoon,
I have inserted an area of isolated thunderstorms along and just
north of the boundary. If surface based storms develop along the
front across east central KS they will most likely become severe.
Most models show between 3,000 and 4,500 J/KG MLCAPE developing in
the warm sector ahead of the front across east central KS. The
effective shear between the surface and 500mb will be around 45
KTS, which given the high MLCAPE would favor supercell
thunderstorms that would produce large hail and damaging wind
gusts. The 850mb winds will veer to the southwest through the day,
thus the low-level vertical wind shear will not be favorable for
tornadoes, unless a storm moves along the boundary and the updraft
does not become undercut, then there may be a chance for a
supercell to produce a tornado. There is s chance that the CAP may
hold Tuesday Afternoon and the front may move through the CWA dry.
Highs will vary from the lower to mid 80s across east central KS
to the mid 60s across north central KS.
.LONG TERM...(Tuesday Night through Monday)
Issued at 359 PM CDT MON APR 6 2015
An active weather pattern is expected for the middle part of this
week with periods of strong to severe thunderstorms likely.
By Tuesday night, a mid-level trough will be digging southward
across the far western U.S. before becoming positively tilted as it
advances towards the Rockies on Wed. At the surface, low pressure
will be centered near the Oklahoma panhandle with an associated cold
front extending into east central Kansas by the late afternoon and
evening hours on Tue. There still are some model discrepancies with
the exact placement of this boundary, but more models have been
trending toward the cap eroding away significantly enough during the
afternoon hours to support the potential for some isolated to widely
scattered thunderstorm development late afternoon through early
evening hours before becoming elevated by mid/late evening. If the
cap is in fact able to weaken, then models suggest significant
instability with surface-based CAPE of values upwards of around
2500-3500J/kg and 0-6km bulk shear of 35-45kts. Any storms that
develop will likely be supercells and the primary threats will be
large hail and damaging winds. Have added a mention of slight chance
PoPs for scattered thunderstorms for the entire CWA overnight into
Wed. morning as models show increasing isentropic lift. As a result,
could see scattered elevated storms into Wed. morning.
The best chance for severe storms will be on Wed. as the front
gradually lifts northward across the area as a warm front. There are
still some model discrepancies with regards to how far north the
warm front will track across the area, which will have a significant
impact on temperatures. It looks to be a strong enough boundary that
a decent temperature gradient should set up somewhere north of I-70,
with highs ranging from the middle 60s to near 80 degrees from
northwest to southeast. With much of the southeastern half of the
forecast area expected to be in the warm sector through the day,
breezy southerly winds will support warm-air advection into east
central Kansas and also lead to decent moisture advection as
dewpoints look to rise into the 60s. The dryline looks to extend
into central/south central Kansas Wed. afternoon and south central
Kansas may be the initiation point for isolated to scattered
supercell thunderstorm development as the triple-point should be
located near or just north of the Wichita area. With the warm front
only pivoting slightly over the area into Wednesday evening and with
an increasing southwesterly low-level jet nearly parallel to the
boundary, expect storms to track northeastward along the boundary.
The cap looks to significantly weaken during the afternoon hours and
conditions will be prime for strong to severe supercell thunderstorm
development as CAPE values reach 3000-3500J/kg, 40-50kts of 0-6km shear,
and 150-250m2/s2 of 0-1km helicity. With these healthy conditions in
place, expect isolated to scattered supercells with large hail,
damaging winds, and some tornadoes possible. This will be a day that
we want to continue to keep a very close eye on.
Expect thunderstorms to continue through the overnight hours into
Thursday morning, but soundings show that this activity should
become elevated. By Thursday morning, models show the mid-level
trough moving into the Central Plains and will pivot from being
positively-tilted to negatively-tilted. This pivot in the tilt will
allow the trough to more quickly push the low pressure system and
associated cold front eastward out of the area and, thus, have
continued to trend with a faster exit of precipitation out of the
area with dry conditions by Thursday night. With this faster exit of
the cold front, the severe potential for Thursday afternoon/evening
should remain to the east across Missouri. Depending upon the timing
of the frontal passage, could see Thursday high temperatures ranging
from the low 60s to low 70s.
Friday afternoon through Saturday look to remain dry for the most
part with surface high pressure in control. Although a passing
shower could occur Saturday during the day, it looks like the chance
is very small with minimal moisture to work with. Saturday night
will set the stage for possibly a more active Sunday as moisture
advection will be underway as a low pressure trough further develops
over the Southern Rockies and begins to eject into the Southern and
Central Plains on Sunday morning. The best chance for thunderstorms
will be in the afternoon Sunday likely being the best near peak
heating as further destabilization of the boundary layer takes
shape. Timing on this event and any severe potential is uncertain
at this point as shear profiles and a few other key parameters don`t
seem to be overly impressive. As the overall system is progged to
be a bit slow moving, some showers could linger into Monday morning
as well.
Temperatures look to remain in mid 60s to 70s for highs and low
temperatures only reaching into the 40s and low 50s which is close to
normal for this time of year.
&&
.AVIATION...(For the 00Z TAFs through 00Z Tuesday Evening)
Issued at 647 PM CDT MON APR 6 2015
Complicated forecast leading to quite low confidence. Limiting
stratus nearly out of all terminals but easterly winds developing
should allow for redevelopment by 06Z. Guidance struggling to
various degrees but stayed closer to RAP and GFS for build down to
IFR and LLWS as jet increases. At this point convective chances in
the 04Z-14Z period look too low to include, with TOP and FOE of
more concern than MHK. Southwest winds should mix down as low
pressure moves near/just NW of terminals around 18Z for return to
VFR.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Gargan
LONG TERM...Drake/Hennecke
AVIATION...65
AREA FORECAST DISCUSSION
NWS TOPEKA KS
406 PM CDT Sun Apr 5 2015
.SHORT TERM...(This Evening through Monday)
Issued at 402 PM CDT SUN APR 5 2015
Tonight and Monday...the amplified upper level trough will begin to
approach the northern CA coast by 00Z TUE. A broad area of
southwesterly mid and upper level flow will spread northeast across
the plains states.
Through the evening hours deeper moisture will
spread northward across the CWA. Low stratus has already moved north
into the southeast counties and will spread northward through the
night. The NAM, GFS, RAP and members of the WRF models all show weak
isentropic lift developing at the 290K theta level. This may provide
for periods of light drizzle after midnight and into the mid morning
hours of Monday. I suppose if there is enough drizzle some areas
could see a couple hundredths of an inch of QPF from late Tonight
through the mid morning hours of Monday. Overnight lows will only
drop into the lower 50s, given the southerly winds and low-level
moisture advection through the night.
Monday, An elevated mix layer from the high plains will spread
across the CWA. This will cause a large capping inversion to form.
The forecast soundings show the EML will be at 840MB and the
moisture will only be as deep as 900mb, thus even taking the parcel
from the top of the moist layer would not break the cap.
Therefore, we will not see thunderstorms through the day on Monday.
We may not even see showers once the boundary layer mixes deep
enough to end the low-level isentropic lift and the drizzle chances.
Forecast soundings show the stratus holding for most of the day
across the eastern counties of the CWA. The western counties may
become partly cloudy to mostly sunny. There will most likely be a
rather sharp temperature gradient across the CWA with low to mid 80s
across the southwest counties and highs only reaching to near 70
degrees across the extreme eastern counties of the CWA. Southerly
surface winds will increase to 15 to 25 MPH with gusts of 30 to 35
MPH as a lee surface low deepens across western KS.
.LONG TERM...(Monday Night through Sunday)
Issued at 402 PM CDT SUN APR 5 2015
By Monday night, surface low pressure will be centered over central
Kansas with the dryline expected to track as far east as into
central Kansas with the associated warm front extending into
northeast Kansas. While most models show the surface low slowly
lifting northeast Monday night through Tuesday, there is uncertainty
with how long precipitation will stick around. At this time, the
better chances for precipitation should be focused along and north
of the warm front near the Kansas/Nebraska border, and then shift
into far eastern Kansas as the surface low tracks eastward. What the
models do agree with is a very strong cap being in place Monday
night through Tuesday with a decent amount of elevated CAPE.
However, model soundings show such shallow saturation in the low
levels that confidence is low in even elevated thunderstorms being
able to develop, but a few scattered showers may be possible. With
this system being so slow-moving, models show the associated frontal
boundary being draped across the northern part of the forecast area
by Tuesday morning, however there are model discrepancies with the
exact location. Expect strong southerly flow in the warm sector
Monday night along with partly to mostly cloudy skies, so overnight
low temperatures should be mild in the upper 50s to mid 60s.
However, locations north of the boundary should see a sharper
temperature gradient with lows in the low/mid 50s. This distinct
temperature gradient will continue through the day on Tuesday as
models show the boundary still lingering across the CWA. Once again,
the exact location of this gradient is uncertain due to model
discrepancies in the boundary location, however Tuesday high
temperatures may range from the middle 60s to low/mid 80s. This
boundary will finally shift east of the area Tuesday evening, but
models show the potential for some thunderstorms to develop along
this boundary late Tuesday afternoon into Tuesday evening as it
shifts east. However, the models are split on whether or not the cap
will be broken by then, with the NAM showing a strong cap while the
GFS/ECMWF show little to no cap. If the cap is able to weaken enough
to support thunderstorm development, there looks to be upwards of
around 2000 J/kg of CAPE with around 40kts of 0-6km bulk shear, so
some severe thunderstorms would be possible with large hail and
strong winds being the primary threats.
A much stronger system is expected by Wednesday/Wednesday night as
the mid-level trough that will move into the western U.S. on Tuesday
quickly advances into the Rockies by Wednesday and helps to push a
strong low pressure system into the region. Models show a warm front
associated with this next system draped across far southern Kansas
near the Oklahoma border by Wednesday morning, with the boundary
lifting northward into the forecast area Wednesday afternoon and
evening. However, there is uncertainty with how quickly this front
will surge northward and just how far north it will track. 12z model
runs showed the GFS/GEM tracking faster and further north while the
ECMWF/NAM were slower and thus limited on their northern extension.
While these details will need to be worked out in the coming days,
MUCAPE values may be upwards of at least 1500-2500 J/kg, 30-40+ kts
of 0-6km bulk shear, 0-1km helicity values around 150-250 m2/s2, and
limited CIN. As a result, supercellular thunderstorms are expected
with all severe threats possible -- large hail, damaging winds, as
well as some tornadoes possible. The temperature gradient will
continue through Wednesday with highs potentially ranging from mid
60s to mid 70s.
For Thursday, both GFS and ECMWF do indicate best potential for
thunderstorm activity to be in the afternoon into early evening.
However, the GFS does seem to be faster and progression is more
quickly to the North with a more negative tilt to the upper level
trough. This does create some uncertainty for how much and how long
the best conditions will exist for any severe threat over extreme
eastern KS. Any major activity looks to be East of Hwy 75 for the
most part as good moisture, shear and instability are better just
off to the East. During the mid to late afternoon time frame a jet
streak may also help to enhance storms along the cold front which
looks to be making its way through the very eastern portions of the
outlook area at this time. As a result, the focus for storms by early
evening does look to be more over western MO.
After the cold front makes its way through, more zonal flow sets up
with a quick transition into a more amplified ridge for Saturday
into Sunday morning in response to yet another potential trough
digging into the four corners region. This could bring some more
showers and potential thunderstorm activity later during the day
Sunday into evening to our area.
Temperatures for Thursday through the end of the period should be trending
on the pleasant side with highs in the upper 60s and lower 70s with
lows in the lower 40s initially but creeping up to the 50s by later
in the period.
&&
.AVIATION...(For the 18Z TAFs through 18Z Monday Afternoon)
Issued at 1227 PM CDT SUN APR 5 2015
Ceilings throughout the day should remain VFR. At 00Z, ceilings
will begin to drop to MVFR levels, eventually reaching IFR by 07Z.
Soundings are continuing to indicate light drizzle throughout the
entire morning accompanied by IFR ceilings. It is possible at some
point in the morning terminals will see LIFR conditions for a short
period, but cannot pinpoint timing this far out; therefore, have
left it out of the TAFs at this time.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Gargan
LONG TERM...Drake/Hennecke
AVIATION...Heller
AREA FORECAST DISCUSSION
NWS JACKSON KY
1051 PM EDT MON APR 6 2015
.UPDATE...
ISSUED AT 1051 PM EDT MON APR 6 2015
THE AREA OF SHOWERS THAT AFFECTED SOUTHERN PORTIONS OF THE CWA
HAVE MOVED EAST OF THE REGION THIS HOUR. WSR-88D RADAR SHOWS A
AREA OF SHOWERS ACROSS CENTRAL KY MOVING SOUTH AND EAST...HOWEVER
THIS AREA OF SHOWERS HAS CONTINUED TO WANE OVER THE PAST FEW
HOURS. GIVEN THIS FELT IT JUSTIFIED DROPPING POPS FOR PORTIONS OF
THE NIGHT. ALL EYES THEN TURN TO THE WEST...WHILE A SUBTLE UPPER
LEVEL WAVE MOVES THROUGH THE FLOW AS WE MOVE THROUGH THE NIGHT
INTO EARLY TOMORROW. WHILE IT SHOULD BE SAID THAT THE GUIDANCE
CONTINUES TO STRUGGLE TONIGHT...THE HRRR HAS COME BACK TO
PROGRESSING AN AREA OF PRECIP ALONG THE WESTERN CWA BORDER TOWARD
THE DAWN HOURS TUESDAY. DID STICK CLOSE TO PREVIOUS FORECAST FOR
THAT PERIOD...GIVEN CONTINUED UNCERTAINTY ON NEXT AREA OF PRECIP
AND STILL LOOKED REASONABLE BASED ON LATEST MESO MODEL GUIDANCE.
ALSO UPDATED GRIDS TO MATCH LATEST OBS AND TRENDS.
UPDATE ISSUED AT 832 PM EDT MON APR 6 2015
WSR-88D CONTINUES TO SHOW AN AREA OF SHOWERS MOVING EAST ACROSS
SOUTHEAST PORTIONS OF THE CWA THIS EVENING. HEAVIER SHOWERS HAVE
GENERALLY BEEN ALONG AND NEAR THE TN/VA BORDER THIS AFTERNOON AND
EVENING. OTHERWISE MOST AREAS ARE CONTINUING TO SEE A PASSING
LIGHT SHOWER FROM TIME TO TIME. EVEN THOUGH MUCH OF THIS HAS BEEN
SHOWERS HAVE KEPT THE MENTION OF THUNDER GIVEN THAT WE CONTINUE TO
BE IN A GENERALLY MOIST AND UNSTABLE ENVIRONMENT. THERE CONTINUES
TO BE A FAIR AMOUNT OF UNCERTAINTY WHERE AND WHEN THE BETTER
SHOWERS AND THUNDERSTORMS SETUP ACROSS THE REGION OVER THE NEXT 24
HOURS. THIS DISAGREEMENT IS ALSO PREVALENT IN MUCH OF THE MESO
MODEL GUIDANCE AS WELL. EITHER WAY THE NEXT BEST WAVE LOOKS TO
MOVE THROUGH...AS WE MOVE INTO TUESDAY MORNING. GIVEN THIS THE
CURRENT POP GRIDS LOOK DECENT. DID UPDATE GRIDS WITH LATEST OBS
AND TRENDS...OTHERWISE GIVEN UNCERTAINTY NO MAJOR CHANGES PLANNED
THIS UPDATE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 405 PM EDT MON APR 6 2015
THE REGION WAS IN A SOMEWHAT ZONAL PATTERN WITH WEST TO WEST
SOUTHWESTERLY FLOW ALOFT BETWEEN A TROUGH OVER EASTERN CANADA AND
THE NORTHERN GREAT LAKES AND A RIDGE CENTERED OVER THE GULF OF
MEXICO. FURTHER WEST...A TROUGH WAS GRADUALLY WORKING ONSHORE OF
THE WEST COAST OF THE CONUS. A SHORTWAVE TROUGH WORKING FROM THE
NORTHERN GREAT LAKES INTO THE NORTHEASTERN CONUS WILL PUSH A COLD
FRONT SOUTH FROM THE GREAT LAKES REGION DOWN TO NEAR THE I 70
CORRIDOR OR SLIGHT SOUTH OF THAT...BUT REMAIN NORTH OF THE OH
RIVER. THEN...AS THE TROUGH WORKS FURTHER INTO THE WESTERN
CONUS...THIS BOUNDARY WILL RETREAT NORTH LATE IN THE SHORT TERM
PERIOD WITH AND AN OLD BOUNDARY CURRENTLY EXTENDING FROM THE
CENTRAL PLAINS INTO THE DEEP SOUTH ALSO BECOMING MORE ILL DEFINED
AND RETREATING NORTH...POSSIBLY NORTH OF THE OH RIVER LATE. THIS
WILL OCCUR AS HEIGHTS RISE ACROSS THE SOUTHEASTERN CONUS.
AN AREA OF SHOWERS AND VERY FEW EMBEDDED THUNDERSTORMS AT PRESENT
IS APPROACHING OF EASTERN KENTUCKY FROM CENTRAL AND WESTERN KY AND
MIDDLE TN ASSOCIATED WITH ISENTROPIC LIFT OVER THE BOUNDARY TO OUR
SOUTHWEST AND WEST. RAINFALL OF NEARLY A HALF OF AN INCH HAS
OCCURRED AT KBNA. THE GENERAL MODEL CONSENSUS IS FOR THIS ACTIVITY
TO BE MOST WIDESPREAD ACROSS THE SOUTHERN CWA DURING THIS
EVENING...ALTHOUGH ISOLATED TO SCATTERED ACTIVITY IS POSSIBLE
ACROSS THE NORTH. NOT MUCH IN THE WAY OF THUNDER IS EXPECTED WITH
THIS AS THE ATMOSPHERE CONTINUES TO MOISTEN. HOWEVER...SOME
LOCALLY HIGHER RAINFALL IS POSSIBLE IN ANY HEAVIER SHOWERS OR ANY
THUNDERSTORMS.
AFTER THAT...MCS ACTIVITY SHOULD BEGIN TO DEVELOP SOUTH OF THE
FRONT TO OUR NORTH AND POSSIBLY NEARER TO THE BOUNDARY TO THE
SOUTHWEST OF THE AREA. CONFIDENCE IN THE DETAILS AND EVOLUTION OF
THIS IS NOT HIGH...WITH DIFFERENCES FROM MODEL RUN TO MODEL RUN.
HOWEVER... PRECIP CHANCES APPEAR BEST THIS EVENING...WITH SOMEWHAT
OF A LULL TOWARD MIDNIGHT INTO THE OVERNIGHT HOURS. TOWARD DAWN
AND INTO TUESDAY MORNING APPEARS TO BE THE NEXT PERIOD WITH THE
HIGHEST CHANCES FOR SHOWERS AND THUNDERSTORMS. THE NORTHERN PART
OF THE AREA COULD EXPERIENCE THE MORE PERSISTENT ACTIVITY OR AT
LEAST QPF FROM THIS AS THEY WILL BE CLOSER TO THE BOUNDARY. THE
MODEL CONSENSUS IS FOR A SHORTWAVE TROUGH TO MOVE THROUGH THE
REGION TOMORROW AFTERNOON INTO TOMORROW EVENING...WITH HEIGHTS
THEN RISING ACROSS THE SOUTHEASTERN CONUS. WITH THE LOSS OF
DAYTIME HEATING AND THE BOUNDARY RETREATING NORTH...CHANCES FOR
SHOWERS AND THUNDERSTORMS APPEAR AS IF THEY WOULD DECREASE FOR A
WHILE FROM MID TO LATE EVENING INTO THE OVERNIGHT HOURS.
HOWEVER... ADDITIONAL WEAK WAVES IN THE FLOW MAY LEAD TO NOCTURNAL
DEVELOPMENT IN THE WARM AND MOIST AIRMASS IN PLACE ACROSS THE OH
VALLEY AND MS VALLEY REGION LATE IN THE PERIOD.
WITH A MUCH MORE MOIST AIRMASS IN PLACE AND RATHER PERSISTENT
CLOUD COVER EXPECTED FOR MUCH OF THE PERIOD...DIURNAL RANGES WILL
BE MORE LIMITED THAN RECENT DAYS. PARTIAL CLEARING COULD BRING
SMALL RIDGE/VALLEY SPLITS TONIGHT AND OR TUESDAY NIGHT IF AND
WHERE IT OCCURS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 405 PM EDT MON APR 6 2015
THE EXTENDED PERIOD LOOKS TO BE QUITE ACTIVE WITH MULTIPLE
IMPULSES RIDING OVER A BROAD RIDGE SET UP ACROSS THE EASTERN
CONUS...AND A WARM FRONT STALLED OUT NORTH OF THE REGION.
THE IMPULSES MOVING OVER THE RIDGE AND ALONG THE BOUNDARY
WILL BRING RAIN AND THUNDERSTORM CHANCES THROUGH THE END OF
THE WORK WEEK. THE RISK OF ORGANIZED AND MORE THREATENING
STORMS DEVELOPS LATER THURSDAY AND CONTINUES THROUGH FRIDAY
DUE TO THE APPROACHING SFC LOW AND TROF. THE SFC LOW THEN
LIFTS TOWARDS THE GREAT LAKES REGION ON FRIDAY WITH A SLOW
MOVING COLD FRONT PASSING THROUGH THE AREA FRIDAY EVENING.
THERE ARE SOME DIFFERENCES BETWEEN THE MODELS ON THE TIMING
OF THE FRONTAL PASSAGE SO HAVE WENT WITH A COMPROMISE BETWEEN
GFS/ECMWF. ADDITIONALLY... THERE WILL BE AMPLE MOISTURE FOR
THE STORMS TO TAP INTO...WITH PW VALUES EXCEEDING 1.25" OR ABOVE 2
STANDARD DEVIATIONS ABOVE NORMAL. THEREFORE...MODERATE TO HEAVY
RAINFALL WILL BE A THREAT FOR THE END OF THE WEEK.
DRIER WEATHER RETURNS FOR THE WEEKEND AS A SFC RIDGE BUILDS IN
OVER THE OHIO VALLEY. THIS WILL ALSO BRING MORE SEASONABLE
TEMPERATURES TO THE STATE FOLLOWING A WEEK OF WELL ABOVE NORMAL
TEMPERATURES....WHERE SOME LOW 80S COULD BE SEEN...DESPITE THE
CLOUDINESS AND PERIODS OF RAIN. THE BEGINNING OF NEXT WEEK BRINGS
MORE CHANCES FOR RAIN AS ANOTHER TROF AND SURFACE LOW MOVES
TOWARDS OUR AREA.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 738 PM EDT MON APR 6 2015
LATE THIS AFTERNOON WSR-88D RADAR SHOWED AN AREA OF SHOWERS
PROGRESSING ACROSS THE SOUTHERN PORTION OF THE CWA NEAR THE TN/VA
BORDER. THIS AREA OF SHOWERS HAS AFFECTED SOME OF THE SOUTHERN TAF
SITES BUT LOOKS TO STAY MOSTLY SOUTH OF JKL...SJS AND SYM AS IT
PROGRESSES EAST. GIVEN THIS DID KEEP SME AND LOZ IN MVFR CIGS
TONIGHT...AS MORE SHOWERS ACROSS WESTERN AND CENTRAL KY COULD
PROGRESS EAST INTO THESE TAF SITES OVERNIGHT. OTHERWISE MOST SITES
COULD SEE A PASSING SHOWER FROM TIME TO TIME. THERE CONTINUES TO
BE A FAIR AMOUNT OF UNCERTAINTY THROUGH THE TAF PERIOD IN REGARDS
TO CIGS AND PRECIP...AS THE GUIDANCE CONTINUES TO STRUGGLE WITH
WHERE THE BEST PRECIP WILL SETUP. DID BRING TAF SITES DOWN
OVERNIGHT INTO TOMORROW MORNING AS A AREA OF MORE ORGANIZED PRECIP
COULD COME ACROSS THE REGION AS INDICATED BY THE
GUIDANCE...HOWEVER ONCE AGAIN PLACEMENT SEEMS TO BE THE BIGGEST
FORECAST ISSUE FOR THIS PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...JP
LONG TERM...JVM/GREIF
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS CARIBOU ME
734 PM EDT MON APR 6 2015
.SYNOPSIS...
WEAK LOW PRESSURE WILL CROSS EASTWARD THE SOUTH GULF OF MAINE
LATE TONIGHT. HIGH PRESSURE WILL THEN BUILD ACROSS THE REGION
TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TUESDAY/...
700 PM UPDATE: BASED ON LATEST RADAR AND SAT IMAGERY TRENDS AND
RECOMMENDATION FROM THE PRIOR DAY CREW...WE FLATTENED THE POPS AND
SNFL A LITTLE FURTHER S THEN THE PRIOR AFTN FCST UPDATE. THIS
KEEPS CHC POPS OVR N CNTRL PTNS OF THE FA OVRNGT AND CATEGORICAL
POPS OVR E CNTRL AND DOWNEAST MAINE...WITH FAR NRN ME BEING SHUT
OUT COMPLETELY BY THIS EVENT. THIS OUTLOOK IS SUPPORTED BY VERY
DRY AIR ACROSS THE FAR N AND BY THE LATEST FEW HRLY RUNS OF SIM
RADAR HRRR MODEL OUTPUT...WHICH KEEPS SNFL MSLY S OF A BAXTER ST
PARK-HOULTON LINE OVRNGT. WITH A LITTLE MORE IN THE WAY OF CLRG
OVR THE ST JOHN VLY AREA OVRNGT...WE LOWERED FCST OVRNGT LOWS A
FEW DEG THERE...BUT ALL AND ALL...CLD CVR AND SIG MILDER 925-850
MB TEMPS ALF WILL KEEP OVRNGT LOWS MUCH MILDER ACROSS THE N
COMPARED TO LAST NGT... ALBEIT STILL BELOW AVG FOR THIS TM OF
SEASON.
ORGNL DISC: A WARM FRONT WILL LIFT TO THE GULF OF MAINE TONIGHT
THEN STALL WHILE A WEAK LOW MOVES ALONG THE FRONT. HIGH PRESSURE
WILL BEGIN TO RIDGE ACROSS NORTHERN MAINE TONIGHT. AN AREA OF
LIGHT OVERRUNNING SNOW WILL MOVE ACROSS CENTRAL/DOWNEAST PORTIONS
OF THE FORECAST AREA TONIGHT WITH ACCUMULATIONS OF 1 TO 3 INCHES.
SNOW CHANCES WILL DECREASE NORTHWARD ACROSS THE REMAINDER OF THE
REGION DUE TO BUILDING HIGH PRESSURE WITH ONLY A SLIGHT CHANCE OF
SNOW ACROSS EXTREME NORTHERN AREAS. HIGH PRESSURE WILL THEN BUILD
SOUTH ACROSS THE FORECAST AREA TUESDAY. PARTLY/MOSTLY CLOUDY SKIES
WILL OCCUR ACROSS NORTHERN AREAS EARLY TUESDAY WITH DECREASING
CLOUDS DURING THE AFTERNOON. MOSTLY CLOUDY SKIES ALONG WITH A
CHANCE OF SNOW SHOWERS WILL OCCUR ACROSS CENTRAL/DOWNEAST AREAS
TUESDAY MORNING...WITH DECREASING CLOUDS DURING THE AFTERNOON. LOW
TEMPERATURES ACROSS EXTREME NORTHERN MAINE TONIGHT WILL BE
DEPENDENT ON THE EXTENT OF CLOUD COVER. GENERALLY EXPECT LOW
TEMPERATURES TO RANGE THROUGH THE SINGLE DIGITS TO AROUND 10 ABOVE
ZERO ACROSS EXTREME NORTHERN AREAS. HOWEVER..COLDER TEMPERATURES
ARE POSSIBLE IF CLOUD COVER IS LESS EXTENSIVE THAN EXPECTED.
ACROSS THE REMAINDER OF THE REGION...LOW TEMPERATURES ARE
GENERALLY EXPECTED TO RANGE FROM THE MID TO UPPER 20S ACROSS
CENTRAL AREAS...WITH UPPER 20S TO AROUND 30 DOWNEAST. HIGH
TEMPERATURES TUESDAY ARE EXPECTED TO RANGE FROM THE MID 30S NORTH
TO THE LOWER 40S DOWNEAST.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
SHORT TERM: THE MODELS ARE IN GOOD AGREEMENT THROUGH THE PERIOD.
A COLD FRONTAL SYSTEM EXTENDS EAST ACROSS THE SOUTHERN GULF OF
MAINE FROM CAPE COD. HIGHER PRESSURE BUILDS ACROSS MAINE. BY WED
MRNG A WARM FRONT LIFTS NE INTO THE ERN GREAT LAKES...HIGH
PRESSURE BUILDS INTO THE GULF OF MAINE. BY WED EVNG THE WRM FRONT
BEGINS TO MOVE INTO SW MAINE...A LOW PRESSURE FORMS ALONG THE
FRONT OFF OF THE COAST OF DELMARVA THAT WILL TRACK EAST ALONG THE
FRONTAL BOUNDARY. THE FRONT WILL FLATTEN AND SLOW THE INLAND FROM
THE COAST. BY THURS MRNG THE HIGH PRESSURE RIDGE WILL MOVE EAST AS
THE PRIMARY LOW MOVES INTO THE ERN GREAT LAKE REGION. BY THE END
OF THE PERIOD THE WARM FRONT WILL BE MOVING INTO WRN MAINE.
LOADED A BLEND OF THE GFS/GEM/ECMWF/NAM FOR HRLY
T/DP/WNDS/POP/SKYCON. ADDED 15 PERCENT TO WNDS FOR GUSTS OVER LAND
35 PERCENT OVER THE WATERS. LOADED NAWAVE 4 FOR SEAS IN THE
COASTAL WATERS. LOADED WPC GUIDANCE FOR QPF...A BLEND OF
GFS/ECMWF FOR THE LAST TWO PERIODS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AT THE START OF THE PERIOD THE EXTENDED MODELS ARE IN GOOD
AGREEMENT. A LOW AND ASSOCIATED FRONTAL SYSTEM MOVES INTO THE
WESTERN PORTIONS OF MAINE AT THE START OF THE PERIOD. AND SLOWLY
CROSSES THE AREA FINALLY MOVING EAST OF THE AREA SAT MRNG. THE GFS
SHOWS THE COLD CORE LOW REMAINING TO OUR WEST OVER SRN QUEBEC...
THE ECMWF MOVES IT NE INTO NRN QUEBEC...WITH A TROUGH EXTEND SW
INTO SRN QUEBEC. THE GFS THROUGH THE DAY SAT SHOWS THE COLD LOW
DRIFTING SOUTH OVER LAKE ONTARIO. THE ECMWF SHIFTS THE TROUGH
SOUTH OVER LAKE ONTARIO. BOTH MODELS BRING A TROUGH ACROSS NRN
MAINE SAT EVNG THROUGH SUN MRNG. SUN THROUGH THE END OF THE PERIOD
BOTH MODELS BRING A HIGH PRESSURE RIDGE ACROSS THE AREA.
LOADED THE SUPERBLEND. ADDED 15 PERCENT TO WINDS FOR GUSTS OVER
LAND 35 PERCENT FOR GUSTS OVER THE COASTAL WATERS. LOADED NAWAVE 4
FOR SEAS IN THE COASTAL WATERS.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
NEAR TERM: GENERALLY EXPECT VFR CONDITIONS ACROSS NORTHERN AREAS
TONIGHT...THOUGH OCCASIONAL MVFR CONDITIONS ARE POSSIBLE DURING
THE EARLY MORNING HOURS. VARIABLE CONDITIONS RANGING FROM VFR TO
IFR ARE EXPECTED ACROSS CENTRAL/DOWNEAST AREAS THIS EVENING...WITH
MVFR TO LIFR CONDITIONS OVERNIGHT. VFR CONDITIONS ARE EXPECTED
ACROSS NORTHERN AREAS TUESDAY. OCCASIONAL MVFR CONDITIONS ARE
POSSIBLE ACROSS CENTRAL AND DOWNEAST PORTIONS OF THE FORECAST AREA
TUESDAY MORNING...WITH VFR CONDITIONS DURING THE AFTERNOON.
SHORT TERM: VFR CONDITIONS ALL SITES WITH PC ACROSS NRN AND
CENTRAL MAINE AT THE START OF THE PERIOD...BKN SKIES SRN
SITES...WITH DECREASING CLOUDS BCMG PC ALL SITES LATE EVNG.
INCREASING CLOUDS THURS MRNG BCMG MC BHB AND BGR LATE MRNG...LATE
EVNG OTHER SITES. CLOUDY WITH SCT MIXED SHOWERS BY WED EVNG FOR
BHB AND BGR. VFR WITH PC SKIES ACROSS NORTH THURS...VFR WITH MC
HUL. THURS MRNG TO EARLY AFTERNOON. INCREASING CLOUDS AND
DECREASING CEILING AS PCPN MOVES INTO NRN SITES LATE AFTERNOON
THURS. CLOUDY WITH MVFR DECREASED TO IFR IN MIXED PCPN FOR BHB AND
BGR THURS. MVFR ALL SITES DECREASED TO IFR IN PCPN THURS
EVNG...BCMG IFR ALL SITES EARLY FRI MRNG IN INTERMITTENT PCPN. IFR
CONDITIONS WILL GIVE WAY TO MVFR CONDITIONS LATE SATURDAY.
&&
.MARINE...
NEAR TERM: WINDS/SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY
LEVELS TONIGHT THROUGH TUESDAY. VISIBILITIES WILL BE REDUCED IN
RAIN/SNOW TONIGHT...WITH A CHANCE OF SNOW SHOWERS TUESDAY MORNING.
SHORT TERM: A SMALL CRAFT ADVISORY MAY BE REQUIRED WED AND
THURS...WINDS GUSTS WILL BE IN THE LOWER TO MIDDLE 20S DURING THE
DAYLIGHT HRS BOTH DAYS.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...VJN
SHORT TERM...NORTON
LONG TERM...NORTON
AVIATION...VJN/NORTON
MARINE...VJN/NORTON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
752 PM EDT MON APR 6 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 429 PM EDT MON APR 6 2015(TODAY AND TONIGHT)
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW CONFLUENT WESTERLY FLOW
ACROSS THE UPPER LAKES BTWN NRN BRANCH TROF OVER ERN CANADA AND SRN
BRANCH RIDGE OVER THE CNTRL CONUS WHICH IS DOWNSTREAM OF A STRONG
TROF ALONG/JUST OFF THE W COAST. SNOW THAT AFFECTED MUCH OF SRN
UPPER MI LAST NIGHT/EARLIER TODAY HAS LARGELY ENDED AS SUBTLE
SHORTWAVE/STRONGER RIGHT ENTRANCE FORCING FROM UPPER JET ALONG AND
LOW/MID LEVEL FRONTOGENESIS HAVE SHIFTED E. TO THE N...A DRY AIR
MASS ASSOCIATED WITH SFC HIGH PRES RIDGING FROM
SASKATCHEWAN/MANITOBA INTO NRN ONTARIO/NRN LAKE SUPERIOR CONTINUES
TO FEED TO THE S AND W.
RIGHT ENTRANCE OF THE UPPER JET WITHIN THE CONFLUENCE ZONE REMAINS
OVER THE UPPER MISSISSIPPI VALLEY/UPPER LAKES REGION TONIGHT. THERE
ARE SOME HINTS THAT ANOTHER SUBTLE SHORTWAVE AND RIBBON OF
FRONTOGENESIS WILL STREAK ACROSS FAR SCNTRL UPPER MI THIS EVENING.
THIS MAY LEAD TO ANOTHER BAND OF SNOW STREAKING ACROSS MAINLY
MENOMINEE COUNTY. LATEST RAP/HRRR SUPPORT THIS IDEA AS DO THE 12Z
NAM AND HIRES WRF-ARW/NMM TO VARYING DEGREES. RADAR TRENDS UPSTREAM
LEND SOME SUPPORT AS WELL. WILL SHOW AN UPTICK IN POPS ACROSS THE
SRN HALF OF MENOMINEE COUNTY THIS EVENING WITH SNOW ACCUMULATIONS
PROBABLY LESS THAN 1 INCH. EXPECT A SHARP CUTOFF TO THE SNOW FARTHER
N AS DRIER AIR FROM THE HIGH PRES RIDGE TO THE N AND NE CONTINUES TO
ADVECT S AND W. WILL CARRY SCHC POPS AS FAR N AS US-2 FROM IRON
RIVER TO ESCANABA. SNOW WILL END OVERNIGHT. EXPECT MIN TEMPS IN THE
20S ACROSS THE AREA...THOUGH SOME TEENS ARE POSSIBLE IN THE USUAL
COLDER SPOTS ACROSS THE N AND E AS CLOUDS MAY THIN ENOUGH TO AID
COOLING OVERNIGHT.
QUIET DAY EXPECTED ON TUE AS ALL MODEL GUIDANCE IS IN GOOD AGREEMENT
ON DRY AIR DOMINATING IN THE LOWER LEVELS. FAVORED THE LOWER SIDE OF
GUIDANCE FOR TEMPS WITH THE IDEA THAT FAIRLY THICK HIGHER CLOUDS
WILL PREVENT SIGNIFICANT WARMING. E TO NE WIND ALSO ARGUES FOR THE
COOLER SIDE OF GUIDANCE...ESPECIALLY SO FROM THE KEWEENAW ACROSS THE
NCNTRL AND S OF KESC NEAR LAKE MI. LOW TO MID 30S SHOULD BE THE RULE
IN THOSE AREAS. ELSEWHERE...TEMPS SHOULD RISE TO AROUND 40F...
HIGHEST WHERE E TO NE WINDS DOWNSLOPE.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 356 PM EDT MON APR 6 2015
THE LONG TERM FORECAST CONTINUES TO BE A CONTINUALLY FRUSTRATING
EXPERIENCE WHEN ATTEMPTING TO PIN DOWN THE FINER DETAILS OF THE
FORECAST. ESPECIALLY WITH THE UPPER GREAT LAKES REGION ON THE
NORTHERN EDGE OF THE DISTURBANCES AND HAVING THERMAL PROFILES THAT
SUPPORT MIXED PRECIPITATION AND FREEZING RAIN.
TUE NIGHT INTO WED MORNING A SHORTWAVE LOOKS TO MOVE S OF THE AREA
OR OVER THE SRN CWA. STILL LOTS OF UNCERTAINTY WITH TRACK OF THE
SHORTWAVE...LOCATION AND AMOUNT OF QPF...AND TEMPERATURE PROFILES.
THEREFORE...PRECIP AMOUNT AND TYPE ARE VERY MUCH IN QUESTION AS
WELL. IF THE COLDER GFS/ECMWF SOLUTION VERIFY...ANY PRECIP THAT
FALLS WOULD BE MORE SNOW TRANSITIONING TO FREEZING DRIZZLE AS MID
LEVEL MOISTURE CUTS OUT AND E WINDS FORCE ONSHORE/UPSLOPE PRECIP
INTO SCENTRAL UPPER MI. THE WARMER ALOFT NAM AND GEM WOULD RESULT IN
MORE FREEZING RAIN TURNING TO FREEZING DRIZZLE. THIS BEING
SAID...THE SNOW OR RAIN PORTION IS STILL QUITE UNCERTAIN. FREEZING
DRIZZLE WED MORNING SHOULD BE LIGHT AS LOW LEVEL MIXING SHOULD ALLOW
NEAR SFC LAYERS TO DRY OUT SOME.
WED AFTERNOON/EVENING LOOKS DRY INLAND...BUT COULD SEE DRIZZLE IN
UPSLOPE AREAS FROM THE E WINDS...MAINLY CENTRAL UPPER MI AND THE
KEWEENAW.
A STRONGER SHORTWAVE AND SFC LOW WILL EJECT OUT OF THE CENTRAL
PLAINS WED NIGHT...BRINGING A SURGE OF WARM AIR OVER THE CWA. MODELS
DO NOT AGREE WELL ON THE FINER DETAILS AND DO NOT HAVE GOOD RUN TO
RUN CONTINUITY. MAIN CONCERN EARLY IN THE EVENT IS WITH FREEZING
RAIN POTENTIAL WED NIGHT INTO THU MORNING. MID LEVEL TEMPS WILL
EASILY SUPPORT ALL LIQUID PRECIP...WITH SFC TEMPS DETERMINING
FREEZING RAIN POTENTIAL AS LOW LEVEL COLD AIR WILL BE TOO SHALLOW
FOR SLEET. FREEZING RAIN DOES LOOK LIKE A STRONG POSSIBILITY DURING
THIS TIME...BUT AMOUNTS OF QPF ARE STILL VERY MUCH IN QUESTION. IT
LOOKS AS THOUGH THE SYSTEM WILL PHASE WITH A NRN STREAM SYSTEM LATER
THU INTO FRI...BRINGING COLDER AIR IN FROM THE WNW LATE THU INTO
FRI. THIS FORECAST PERIOD IS EVEN MORE IN QUESTION AS MODELS
STRUGGLE WITH PHASING. IT DOES APPEAR PRECIP IS LIKELY...THE
UNCERTAINTY HAS MORE TO DO WITH PTYPE AND PRECIP AMOUNTS...FOR WHICH
SMALLER SCALE DETAILS WILL BE CRUCIAL. GIVEN THE GENERAL CONSENSUS
IDEA...THINK THAT PRECIP WILL TRANSITION FROM RAIN TO FREEZING RAIN
TO SNOW OVER WRN UPPER MI THU EVENING/NIGHT...WITH SIGNIFICANT
AMOUNTS OF EACH POSSIBLE BUT NOT CERTAIN. RAIN SHOULD TRANSITION TO
MORE OF A RAIN/SNOW MIX OVER THE CENTRAL THU NIGHT. THE ECMWF MOVES
THE PRECIP OUT OF THE AREA FRI EVENING WHILE THE GFS LINGERS PRECIP
INTO SAT MORNING. GIVEN POTENTIAL FOR FREEZING RAIN ACCUMULATION WED
NIGHT/THU MORNING AND FREEZING RAIN/SNOW POTENTIAL THU EVENING/NIGHT
WILL CONTINUE TO HIGHLIGHT IN THE HWO.
IT LOOKS LIKE SFC HIGH PRESSURE AND UPPER RIDGING SHIFT ACROSS THE
CWA OVER THE WEEKEND...WITH A WARM UP POSSIBLE AS THE HIGH SHIFTS E
AND A TROUGH MOVES TOWARD THE AREA FROM THE W. WILL JUST RUN WITH A
CONSENSU OF GUIDANCE FOR SAT-MON.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 752 PM EDT MON APR 6 2015
HIGH PRES RIDGE EXTENDING ACROSS NRN ONTARIO WILL ADVECT LOW-LEVEL
DRY AIR S AND W ACROSS UPPER MI THROUGH TUE. AS A RESULT...VFR
CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW THRU THIS FCST PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 429 PM EDT MON APR 6 2015
WITH LAKE SUPERIOR SITUATED BETWEEN HIGH PRES THAT WILL MOVE ACROSS
NRN ONTARIO INTO QUEBEC THRU WED MORNING AND A WARM FRONT THAT WILL
REMAIN TO THE S AND SW ACROSS THE PLAINS TO OHIO VALLEY...E TO NE
WINDS WILL PERSIST. TYPICAL FOR E TO NE WINDS...WINDS WILL BE
STRONGEST OVER WRN LAKE SUPERIOR...IN PARTICULAR BTWN THE APOSTLE
ISLANDS AND MN NSHORE WHERE FUNNELING/COASTAL CONVERGENCE ENHANCE
THE WINDS. IN THAT AREA...15-25KT WINDS WILL INCREASE TO 20-30KT
LATER TONIGHT AND CONTINUE THRU TUE NIGHT. EXPECT SOME GALE FORCE
GUSTS TUE AFTN/EVENING. E TO NE WINDS...MOSTLY 15-25KT...WILL THEN
CONTINUE THRU WED AND ON INTO THU AS LOW PRESSURE LIFTS NE FROM THE
CENTRAL PLAINS TO THE GREAT LAKES REGION. AT THIS TIME...IT DOES NOT
APPEAR THAT THE LOW WILL BE STRONG ENOUGH TO RESULT IN GALES AS IT
APPROACHES AND THEN DEPARTS. WINDS WILL BACK AROUND TO THE N AND NW
THU NIGHT AND FRI AS THE LOW EXITS TO THE NE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
144 PM EDT SUN APR 5 2015
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 324 AM EDT SUN APR 5 2015
LIGHT RAIN AND SNOW WILL SPREAD EAST FROM WISCONSIN EARLY THIS
MORNING. THE SNOW MAY ACCUMULATE AN INCH OR TWO NORTH OF I-96 BEFORE
CHANGING TO RAIN BY LATE MORNING. A FRONTAL BOUNDARY WILL REMAIN
STRETCHED ACROSS LOWER MICHIGAN FOR A FEW DAYS. SEVERAL PERIODS OF
SHOWERS ARE POSSIBLE NEXT WEEK ALONG WITH A FEW THUNDERSTORMS
TUESDAY.
&&
.UPDATE...
ISSUED AT 1030 AM EDT SUN APR 5 2015
CANCELLED THE WINTER WEATHER ADVISORY NORTH OF I-96 EARLY AS
PRECIPITATION HAS DIMINISHED. THERE IS STILL A CHANCE OF SOME
ADDITIONAL PRECIPITATION NORTH OF THE FRONTAL BOUNDARY TODAY...
ALTHOUGH IT SHOULD BE MAINLY JUST LIGHT RAIN/DRIZZLE AS SFC TEMPS
ARE WARMING.
SNOWFALL REPORTS HAVE BEEN LIMITED THIS MORNING BUT WE HAVE
RECEIVED REPORTS OF AROUND 2 INCHES AT REED CITY AND BIG RAPIDS.
WE WILL HAVE TO WATCH TEMPS ALONG THE I-94 CORRIDOR THIS
AFTERNOON. THIS AREA IS SOUTH OF THE SFC BOUNDARY WHICH APPEARS TO
BE LOCATED ALONG OR JUST SOUTH OF I-96 AT 10 AM. WITH ENOUGH
SUNSHINE IT IS POSSIBLE THAT AZO/BTL/JXN COULD REACH 65. MEANWHILE
CLOUDS AND EASTERLY FLOW WILL KEEP AREAS NORTH OF I-96 STUCK IN
THE 40S.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 324 AM EDT SUN APR 5 2015
FORECAST CONCERNS DEAL WITH PCPN TRENDS THROUGH THE PERIOD.
REGIONAL RADAR SHOWS PCPN MOVING EAST FROM WISCONSIN. MUCH OF THIS
PCPN SO FAR IS GOING INTO MOISTENING THE VERY DRY LOWER LEVELS OF
THE ATMOSPHERE. HRRR CONTINUES TO SHOW LIGHT SNOW DEVELOPING OVER
THE NORTHERN HALF OF THE CWA EARLY THIS MORNING. HOWEVER SHORT RANGE
MODELS ARE NOT AS BULLISH ON QPF AND SO WE SCALED BACK ON ACCUMS.
THIS SYSTEM HAS NEVER BEEN A HIGH CONFIDENCE SYSTEM DUE TO IT/S
DEPENDENCE ON MOSTLY FRONTOGENETICAL FORCING FOR PCPN DEVELOPMENT.
WEAK LOW PRESSURE PUSHED A TROUGH SOUTH OVER THE CENTRAL CWA A FEW
HOURS AGO AND THIS BOUNDARY WILL BE THE FOCUS FOR PCPN DEVELOPMENT
OVER THE NEXT FEW DAYS. UPSTREAM RADAR SHOWS 30+ DBZ WESTWARD TO THE
MISSISSIPPI. THUS WE/LL KEEP THE WINTER WEATHER ADVISORY GOING.
SREF/HRRR INDICATE THAT THE PCPN SHOULD WIND DOWN BY LATE MORNING.
LOOKING AT A COUPLE OF INCHES OF SNOW MAINLY NORTH OF A PENTWATER TO
ALMA LINE.
LOW PRESSURE IN THE PLAINS WILL PUSH WARMER AIR NORTHWARD MONDAY AND
TUESDAY WHICH WILL STRENGTHEN THE BAROCLINIC ZONE OVER THE CWA. AS
THE LOW MOVES EAST...RAIN WILL DEVELOP MONDAY NIGHT AND CONTINUE
TUESDAY. MONDAY WILL BE THE WARMER OF THE TWO DAYS WITH HIGHS NEAR
60. BUT THEN THE BOUNDARY WILL SINK SOUTH AND NORTHEAST WINDS WILL
STRENGTHEN PULLING IN COOLER AIR FROM ONTARIO. MODELS INDICATE
ELEVATED INSTABILITY TUESDAY. LI/S NEAR -4C COUPLED WITH MUCAPE
500-1000 J/KG POINT TOWARD SOME THUNDERSTORMS SOUTH OF I-96. TSRA
WAS ADDED TO THE GRIDS TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 324 AM EDT SUN APR 5 2015
THE MAIN CHALLENGE IN THE LONG TERM DEALS WITH THE RISK FOR MIXED
PRECIPITATION TUESDAY NIGHT AND ALSO THE HEAVY RAIN/THUNDER RISK
GOING INTO THE END OF THE WEEK.
MODELS CONTINUE TO SHOW AN ELEVATED WARM LAYER ABOVE A NEAR FREEZING
LOW LEVEL LAYER TUESDAY NIGHT UP AROUND HARRISON AND MOUNT
PLEASANT. BASED ON THIS WILL MAINTAIN THE POSSIBILITY OF ZR MAINLY
NORTH OF A ALMA TO LUDINGTON LINE. TRENDS SEEM TO SUPPORT LESS
SHALLOW COLD AIR. TRIGGERING THE PRECIPITATION WILL BE A WARM FRONT
SITUATED OVER LOWER MI WITH THE NOSE OF A LOW LEVEL JET ACROSS THE
FRONT. WILL NEED TO MONITOR THE THUNDER RISK. HIGHEST POPS MAINLY
OVER SOUTHERN LOWER MI...CLOSER TO THE FRONT AND GULF MOISTURE.
MODELS ARE IN BETTER AGREEMENT IN DRAWING UP GULF MOISTURE THU INTO
THU NIGHT...SENDING THE WARM FRONT NORTH OF GRAND RAPIDS.
INSTABILITY ARRIVES AS WELL. ADDED THUNDER TO THE FORECAST FOR MUCH
OF THE REGION. POPS HAVE BEEN RAISED AS WELL. RAIN COULD BE HEAVY
GIVEN THE LOW LEVEL JET IN PLACE. MODELS VARY ON THE TIMING OF THE
COLD FRONTS ARRIVAL LATER THU NIGHT OR FRI. WILL HOLD OFF ON THE
THUNDER RISK FOR FRI AT THIS TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 138 PM EDT SUN APR 5 2015
A WARM FRONT THAT IS DRAPED ACROSS THE AREA WILL BE THE DIVIDING
LINE FOR STRONG WIND GUSTS VS. LIGHT AND VARIABLE WINDS. GUSTS TO
25 KTS ARE ALREADY BEING REALIZED FOR SOUTHERN LOWER MI AND WILL
CONTINUE TO FEATURE IN THE AZO/BTL/JXN TAF SITES WHICH ARE SOUTH
OF THE WARM FRONT AND MIXING DOWN STRONGER WINDS. GRR WILL BE
RIGHT UNDERNEATH THE FRONT IT APPEARS FOR MUCH OF THE DAY SO
LIGHT/VARIBLE WINDS ARE WARRANTED.
WINDS GO MAINLY E/SE OVERNIGHT THEN SE/S FOR MONDAY WITH
INCREASING LOWER CLOUDS (SCT) DURING THE LATE MORNING AND
AFTERNOON...WITH LOW CIGS LIKELY ARRIVING BETWEEN 00Z-06Z TUESDAY.
LOOKS LIKE WIDESPREAD IFR STARTING AT THAT POINT AND CONTINUING
THROUGH TUESDAY.
&&
.MARINE...
ISSUED AT 324 AM EDT SUN APR 5 2015
A FAIRLY QUIET DAY ON THE LAKE EXPECTED. 5 TO 15 KNOT WINDS WILL
RESULT IN WAVES 2 FEET OR LESS.
&&
.HYDROLOGY...
ISSUED AT 1220 PM EDT SUN APR 5 2015
A BAND OF 0.10 TO 0.25 INCHES OF PRECIPITATION FELL LAST NIGHT
THROUGH THIS MORNING IN THE FORM OF RAIN AND SNOW ACROSS CENTRAL
LOWER MICHIGAN. THERE WERE A FEW REPORTS OF AROUND 2 INCHES OF
SNOW ACROSS THE MUSKEGON RIVER BASIN. NOT MUCH HYDRO IMPACT
HERE...RIVERS REMAIN MOSTLY LEVEL OR RECEDING.
THE WEATHER PATTERN WILL REMAIN CONDUCIVE FOR PRECIPITATION OVER
THE NEXT WEEK. RAIN WILL DEVELOP MONDAY NIGHT AND PERSIST INTO
TUESDAY...WITH A CHANCE FOR STORMS ON TUESDAY AS WELL. THERE IS A
HIGHER RISK FOR HEAVIER RAIN AND THUNDERSTORMS ON THURSDAY. IN
GENERAL...1 TO 2 INCHES OF RAINFALL IS POSSIBLE OVER THE NEXT
WEEK. THE POTENTIAL IS CERTAINLY THERE FOR HIGHER RAINFALL AMOUNTS
WITH THUNDERSTORMS. THERE IS LOW CONFIDENCE IN FLOODING AT THIS
POINT...BUT RISES ON STREAMS AS WELL AS MAIN STEMS CAN BE
EXPECTED.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...MEADE
SYNOPSIS...04
SHORT TERM...04
LONG TERM...MJS
AVIATION...HOVING
HYDROLOGY...EBW
MARINE...04
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
142 PM EDT SUN APR 5 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM EDT SUN APR 5 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A CONFLUENT NW
FLOW ALOFT OVER THE UPPER GRT LKS BTWN CUTOFF H5 LO OVER NRN QUEBEC
AND POLAR/SUBTROPICAL BRANCH RDG OVER THE ROCKIES. SPRAWLING SFC HI
PRES IS CENTERED OVER MANITOBA...WITH A RDG AXIS ORIENTED SE INTO LK
SUP. THE UPSTREAM 00Z RAOBS SHOW A VERY DRY AIRMASS ASSOCIATED WITH
THIS HI. THE 00Z PWAT WAS 0.13 INCH AT INL /45 PCT OF NORMAL/ AND
ONLY 0.05 INCH AT YPL AND THE PAS MANITOBA. THERE ARE SOME CLDS OVER
THE FAR SCENTRAL CLOSER TO H85 WARM FNT DRAPED W-E ACROSS THE UPR
MIDWEST. THERE ARE SOME SCT MID CLDS OVER THE REST OF THE CWA
ASSOCIATED WITH A WEAK SHRTWV THAT IS SHEARING OUT IN THE NW UPPER
FLOW AND ACCOMPANYING LO PRES TROF. SOME LO CLDS AND EVEN A FEW
FLURRIES HAVE ALSO DVLPD OVER THE NCENTRAL WITH UPSLOPE NE FLOW
ASSOCIATED WITH PASSAGE OF THE LO PRES TROF. TEMPS TO THE N ARE
QUITE CHILLY AS WELL...WITH 00Z H85 TEMP -20C AT YPL. LOOKING TO THE
S...THERE IS A BAND OF SOME RAIN SHOWERS STRETCHING FM SRN MN ACROSS
CENTRAL WI ASSOCIATED WITH APRCH OF ANOTHER WEAK SHRTWV AND SOME
WAA/FGEN TO THE NE OF THE H85 WARM FNT. LOOKING UPSTREAM...THERE IS
A SHRTWV IN THE POLAR BRANCH FLOW RIDING OVER THE ROCKIES RDG. HI
CLDS IN ADVANCE OF THIS FEATURE ARE MOVING THRU THE NRN PLAINS. SOME
LIGHT RA IS FALLING ALONG THE NDAKOTA/SDAKOTA BORDER DESPITE VERY
DRY LLVLS SHOWN ON THE 00Z BISMARCK RAOB.
MAIN FCST CONCERNS IN THE SHORT TERM WL FOCUS ON CLDS TODAY AND THEN
POPS/SN AMOUNTS FOR TNGT ASSOCIATED WITH SHRTWV NOW RIDING OVER THE
ROCKIES RDG AND INTO THE NRN PLAINS.
TDAY...AS WEAK SHRTWV CAUSING BAND OF PCPN IN CENTRAL WI SLIDES TO
THE ESE...THIS AREA OF PCPN WL REMAIN S OF UPR MI. OTHERWISE...MID
LVL SUBSIDENCE/HI PRES BLDG OVER LK SUP WL BRING MAINLY DRY WX.
SEVERAL OF THE HIER RES MODELS INDICATE SOME LO CLDS WL PERSIST AT
LEAST FOR A PORTION OF THIS MRNG OVER MAINLY THE NCNTRL CWA WITH
LIGHT UPSLOPE ENE WIND THAT WL SLOW THE ADVECTION OF THE VERY DRY AIR
SHOWN IN ONTARIO. ALSO ADDED SOME FLURRIES THIS MRNG IN THE UPSLOPE
AREAS OF THE NCENTRAL. WITH AN ENE WIND...EXPECT BLO NORMAL
TEMPS...ESPECIALLY NEAR THE CHILLY WATERS OF THE GREAT LKS. DEEPER
MIXING TO H8 AS OBSVD ON THE 00Z INL RAOB WL ALLOW TEMPS NEAR THE WI
BORDER TO REACH THE LO 40S AWAY FM ANY LK MODERATION AND DESPITE SOME
INCRSG HI CLDS THIS AFTN.
TNGT...MODELS INDICATE UPR CONFLUENCE ZN WL RETREAT TO THE N...
ALLOWING SHRTWV NOW MOVING INTO THE NRN PLAINS TO APRCH. WITH THE
RETREAT OF THE CONFLUENCE ZN...UPR MI IS PROGGED TO FALL INTO THE
RRQ OF 120KT H3 JET MAX THAT IS FCST TO SHIFT AVER FAR SW QUEBEC/
ADJOINING ONTARIO OVERNGT. AS THE H85 WARM FNT/MID LVL FGEN BAND
SHIFT TO THE N UNDER THE DVLPG UPR DVGC IN THE RRQ OF THE JET
STREAK...A BAND OF WAA SN TO THE N OF THE WARM FNT IS PROGGED TO
DEVELOP NEAR THE WI BORDER IN THE EVNG AND DRIFT SLOWLY TO THE N
THRU THE N...ENVELOPING ALL BUT THE KEWEENAW PENINSULA BY 12Z MON.
SOME OF THE MODELS SHOW AS MUCH AS 0.25 TO 0.30 INCH QPF OVER THE
SCENTRAL...IN GOOD AGREEMENT WITH H7 SPECIFIC HUMIDITY FCST IN THE
2.5-3.0 G/KG RANGE. NOT OUT OF THE QUESTION WET SN ACCUMS WITH
NARROW/HIER DGZ MAY APRCH ADVY CRITERIA OVER PORTIONS OF THE
SCENTRAL.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 345 AM EDT SUN APR 5 2015
THE UPPER LOW SPINNING OFF THE PACIFIC NORTHWEST WILL DROP SOUTH
ALONG THE WEST COAST OF THE CONUS OVER THE NEXT COUPLE
DAYS...LEADING TO A TRANSITION TO THE WEATHER PATTERN AWAY FROM
NORTHWESTERLY FLOW ALOFT TO A WESTERLY FLOW BY MID WEEK. WHILE THAT
OCCURS...SEVERAL WAVES WILL EJECT TOWARDS THE AREA AND ALONG A
NEARLY STATIONARY WARM FRONT STRETCHING FROM A LOW IN THE LEE OF THE
CENTRAL ROCKIES THROUGH THE LOWER GREAT LAKES. THAT FRONT WILL SHIFT
NORTH SLIGHTLY LATER TONIGHT AND REMAIN THROUGH TUESDAY AS THE HIGH
PRESSURE RIDGE THAT IS OVER THE AREA AT THE PRESENT TIME SHIFTS
NORTH INTO CANADA. THAT WILL BE THE FIRST POTENTIAL FOR
PRECIPITATION FOR THE CWA. WHILE THERE HAVE BEEN SOME VARIATIONS IN
THE MODEL SOLUTIONS ON THIS NORTHWARD SHIFT OF THE WARM FRONT AND
ASSOCIATED PRECIPITATION...THEY SEEM TO HAVE NARROWED IN ON THE
FOCUS OF THE BEST PRECIPITATION LATE TONIGHT INTO TUESDAY BEING OVER
NORTHERN WISCONSIN AND SOUTHERN UPPER MICHIGAN. DURING THAT
TIME...THINK THE HEAVIEST PRECIPITATION WILL OCCUR WITH THE INITIAL
NORTHWARD PUSH LATE TONIGHT INTO MONDAY MORNING BEFORE THE WESTERLY
MID LEVEL FLOW GENERALLY BECOMES PARALLEL TO THE ISOTHERMS MONDAY
AFTERNOON. DURING THAT BETTER PRECIPITATION...THE THERMAL PROFILE
LOOKS TO STAY BELOW FREEZING AND WOULD EXPECT THE P-TYPE TO REMAIN
AS SNOW. BUT AS THE FORCING WEAKENS DURING THE DAY...THERE ARE HINTS
THAT THE MOISTURE IN THE ICE CRYSTAL REGION WILL CUT OUT AND THE SUB
800MB THERMAL PROFILE IS HOVERING AT OR JUST BELOW FREEZING. THAT
WOULD LEAD TO RAIN/DRIZZLE AND POTENTIAL FOR FZRA WHERE TEMPS ARE
AROUND FREEZING. UNFORTUNATELY CONFIDENCE IS TOO LOW TO GET OVERLY
DETAILED AT THIS POINT...BUT WILL SHOW A MENTION OF RAIN WITH THE
SNOW TO ACCOUNT FOR THE DRYING ALOFT. FORCING DURING MONDAY
AFTERNOON WEAKENS AND REMAINS PINNED ALONG THE WISCONSIN BORDER AND
THROUGH THE SOUTHERN U.P. BEFORE WINDS BACK SLIGHTLY MONDAY NIGHT AS
ANOTHER SHORTWAVE SLIDES THROUGH THE REGION. THUS...WOULD EXPECT
ANOTHER UPTICK IN PRECIPITATION ON MONDAY NIGHT...BUT STILL NEAR THE
WI BORDER AND THE SOUTHERN U.P. LIKE MONDAY AFTERNOON. THE SHORTWAVE
DOES HELP TO BRING ADDITIONAL MOISTURE INTO THE ICE CRYSTAL REGION
FOR PORTIONS OF THE CWA (MAINLY NORTHERN HALF TO 2/3RDS)...BUT THE
MAIN FORCING/MOISTURE IS BELOW THE FAVORED ICE CRYSTAL REGION.
THUS..WOULD EXPECT THE PRECIPITATION TO SOME LIQUID IN IT OVER THE
SOUTH CENTRAL...THEN CHANGING TO ALL SNOW AS YOU HEAD NORTH ACROSS
THE U.P. THEREFORE...THE SURFACE TEMPERATURES WILL LARGELY DETERMINE
THE IMPACT FROM THIS PRECIPITATION MONDAY AFTERNOON INTO TUESDAY
MORNING. WITH THE LOW LEVEL FLOW OUT OF THE NORTHEAST KEEPING COLDER
AIR FILTERING INTO THE AREA...WOULD EXPECT PERIODS OF FREEZING RAIN.
THINK THERE WILL BE ENOUGH WARMING ON MONDAY AFTERNOON TO LIMIT THE
POTENTIAL (EXCEPT ON EXISTING COLD SURFACES)...BUT COOLING MONDAY
NIGHT AND REMAINING INTO TUESDAY WOULD SUPPORT FREEZING RAIN WHERE
THE LIQUID PRECIPITATION OCCURS OVER THE SOUTH CENTRAL. THE SNOW
WILL BE DIMINISH MONDAY MORNING...LIMITING ADDITIONAL
ACCUMULATION...BUT IT STILL LOOKS LIKE SOME LOCATIONS IN SOUTHERN
MENOMINEE COUNTY WILL EXCEED 3 INCHES LATE TONIGHT INTO MONDAY
MORNING. THEN FOR MONDAY NIGHT...EXPECT A DUSTING TO 1.5IN OVER THE
INTERIOR WEST AND CENTRAL.
AS THE SURFACE HIGH NEAR JAMES BAY STRENGTHENS ON TUESDAY
AFTERNOON...EXPECT A HIGH PRESSURE RIDGE TO NOSE BACK SOUTH AND INTO
THE UPPER GREAT LAKES REGION FOR TUESDAY NIGHT INTO WEDNESDAY
EVENING. THIS WILL LEAD TO A DRY PERIOD OVER UPPER MICHIGAN BEFORE
THE NEXT WAVE ARRIVES FOR THE LATER PART OF THE WORK WEEK.
THAT NEXT WAVE IS TIED TO THE UPPER LOW ALONG THE WEST COAST OVER
THE NEXT COUPLE DAYS MOVING THROUGH THE ROCKIES DURING THE MIDDLE OF
THE WEEK AND THEN LIFTING NORTHEAST THROUGH THE GREAT LAKES REGION
THURSDAY-SATURDAY. THIS WILL LEAD TO SEVERAL WAVES OF PRECIPITATION
DURING THAT PERIOD. WON/T GET TOO SPECIFIC IN THE GRIDS DUE TO THE
EVOLVING IDEAS IN THE MODELS...BUT THE FIRST WAVE WILL MOVE THROUGH
ON THURSDAY OUT AHEAD OF THE UPPER LOW. WITH THE WARMING BETWEEN 925-
700MB (PEAKING BETWEEN 1 AND 6C)...WILL SEE THE PRECIPITATION FALL
AS A MIX OR ALL LIQUID. BUT WITH SURFACE TEMPERATURES STILL STAYING
AT OR AROUND FREEZING WITH THE LOW LEVEL EASTERLY FLOW FROM THE
DEPARTING HIGH...WILL CONTINUE TO MENTION A FREEZING RAIN POTENTIAL
FOR THURSDAY MORNING. EXPECT A BRIEF LULL BEHIND THAT FIRST WAVE
BEFORE THE MAIN PRECIPITATION ASSOCIATED WITH THE UPPER LOW LIFTS
NORTHEAST INTO THE GREAT LAKES REGION FOR THE FRIDAY INTO SATURDAY
PERIOD. DIFFERENCES IN THE SPEED OF THE MODELS...AS WELL AS THE
UPPER LOW TRACK...AS IT MOVES THROUGH THE REGION LEADS TO
UNCERTAINTY ON THE PRECIP TYPES. WOULD EXPECT THERE TO BE ENOUGH
WARM AIR TO SUPPORT RAIN FOR MUCH OF FRIDAY (ALTHOUGH THERE COULD BE
SOME FZRA IF IT STARTS EARLY ENOUGH FRIDAY MORNING) BEFORE POSSIBLY
MIXING WITH SNOW FRIDAY NIGHT INTO SATURDAY. THE 00Z GFS CONTINUES
TO BE MUCH FASTER WITH THE LOW MOVING THROUGH AND HAS SHIFTED IT
SIGNIFICANTLY FARTHER TO THE SOUTHEAST...LEADING TO A BETTER
OPPORTUNITY FOR SNOW. LOOKING AT THE 12Z ECMWF ENSEMBLE
MEMBERS...THAT FASTER TREND SEEMS A LITTLE AGGRESSIVE ALTHOUGH THE
SOUTHEAST MOVEMENT IS POSSIBLE WITH SOME ECMWF ENSEMBLE MEMBERS
TRACKING THE LOW THROUGH NORTHERN LOWER MICHIGAN. ALL IN ALL...WITH
THIS PERIOD STILL SEVERAL DAYS OUT...WON/T GET TOO DETAILED AND SHOW
THE GENERAL IDEA FOR POPS AND P-TYPE.
FINALLY...EXPECT TO SEE GRADUALLY WARMING TEMPS THROUGH THE WEEK AS
THE COLD AIR RETREATS TO THE NORTH BUT STILL STAYING AROUND OR BELOW
NORMAL FOR HIGHS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 142 PM EDT SUN APR 5 2015
VFR CONDITIONS EXPECTED ACROSS THE AREA THROUGH THIS EVENING AS DRY
HIGH PRESSURE TO THE NORTH REMAINS IN CONTROL. A WARM FRONT OVER THE
PLAINS AND MS VLY REGION WILL MOVE NORTHWARD INTO THE UPPER GREAT
LAKES TONIGHT. SOME LIGHT SNOW AND LOWER CIGS WILL ACCOMPANY THE
WARM FRONT ACROSS UPPER MICHIGAN...HOWEVER THE DRY NE SFC WIND WILL
KEEP THE HEAVIEST SNOW CONFINED CLOSER TO IRON MOUNTAIN AND
MENOMINEE. THEREFORE...WILL BRING SOME LIGHT SNOW TO IWD AND SAW
OVERNIGHT ALONG WITH LOW END MVFR OR IFR CIGS. DUE TO CMX BEING
FARTHEST FROM THE MOISTURE AND WARM FRONT...EXPECT THAT SITE TO
REMAIN VFR OR HIGH END MVFR THROUGH THE PERIOD WITH ONLY FLURRIES OR
LIGHT SNOW SHOWERS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 345 AM EDT SUN APR 5 2015
WITH THE UPPER GREAT LAKES REGION BETWEEN A HIGH IN SOUTHERN CANADA
AND A WARM FRONT STRETCHING EAST ACROSS THE LOWER GREAT
LAKES...EXPECT PERSISTENT NORTHEAST TO EASTERLY WINDS THROUGH THE
MIDDLE OF THE WORK WEEK. MOST OF THE TIME WINDS WILL STAY BELOW
25KTS...BUT FUNNELING DOWN WESTERN LAKE SUPERIOR COULD LEAD TO GUSTS
UP TO 30KTS LATE MONDAY NIGHT INTO TUESDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...MRD
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1220 PM EDT SUN APR 5 2015
LATEST UPDATE...
HYDRO
.SYNOPSIS...
ISSUED AT 324 AM EDT SUN APR 5 2015
LIGHT RAIN AND SNOW WILL SPREAD EAST FROM WISCONSIN EARLY THIS
MORNING. THE SNOW MAY ACCUMULATE AN INCH OR TWO NORTH OF I-96 BEFORE
CHANGING TO RAIN BY LATE MORNING. A FRONTAL BOUNDARY WILL REMAIN
STRETCHED ACROSS LOWER MICHIGAN FOR A FEW DAYS. SEVERAL PERIODS OF
SHOWERS ARE POSSIBLE NEXT WEEK ALONG WITH A FEW THUNDERSTORMS
TUESDAY.
&&
.UPDATE...
ISSUED AT 1030 AM EDT SUN APR 5 2015
CANCELLED THE WINTER WEATHER ADVISORY NORTH OF I-96 EARLY AS
PRECIPITATION HAS DIMINISHED. THERE IS STILL A CHANCE OF SOME
ADDITIONAL PRECIPITATION NORTH OF THE FRONTAL BOUNDARY TODAY...
ALTHOUGH IT SHOULD BE MAINLY JUST LIGHT RAIN/DRIZZLE AS SFC TEMPS
ARE WARMING.
SNOWFALL REPORTS HAVE BEEN LIMITED THIS MORNING BUT WE HAVE
RECEIVED REPORTS OF AROUND 2 INCHES AT REED CITY AND BIG RAPIDS.
WE WILL HAVE TO WATCH TEMPS ALONG THE I-94 CORRIDOR THIS
AFTERNOON. THIS AREA IS SOUTH OF THE SFC BOUNDARY WHICH APPEARS TO
BE LOCATED ALONG OR JUST SOUTH OF I-96 AT 10 AM. WITH ENOUGH
SUNSHINE IT IS POSSIBLE THAT AZO/BTL/JXN COULD REACH 65. MEANWHILE
CLOUDS AND EASTERLY FLOW WILL KEEP AREAS NORTH OF I-96 STUCK IN
THE 40S.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 324 AM EDT SUN APR 5 2015
FORECAST CONCERNS DEAL WITH PCPN TRENDS THROUGH THE PERIOD.
REGIONAL RADAR SHOWS PCPN MOVING EAST FROM WISCONSIN. MUCH OF THIS
PCPN SO FAR IS GOING INTO MOISTENING THE VERY DRY LOWER LEVELS OF
THE ATMOSPHERE. HRRR CONTINUES TO SHOW LIGHT SNOW DEVELOPING OVER
THE NORTHERN HALF OF THE CWA EARLY THIS MORNING. HOWEVER SHORT RANGE
MODELS ARE NOT AS BULLISH ON QPF AND SO WE SCALED BACK ON ACCUMS.
THIS SYSTEM HAS NEVER BEEN A HIGH CONFIDENCE SYSTEM DUE TO IT/S
DEPENDENCE ON MOSTLY FRONTOGENETICAL FORCING FOR PCPN DEVELOPMENT.
WEAK LOW PRESSURE PUSHED A TROUGH SOUTH OVER THE CENTRAL CWA A FEW
HOURS AGO AND THIS BOUNDARY WILL BE THE FOCUS FOR PCPN DEVELOPMENT
OVER THE NEXT FEW DAYS. UPSTREAM RADAR SHOWS 30+ DBZ WESTWARD TO THE
MISSISSIPPI. THUS WE/LL KEEP THE WINTER WEATHER ADVISORY GOING.
SREF/HRRR INDICATE THAT THE PCPN SHOULD WIND DOWN BY LATE MORNING.
LOOKING AT A COUPLE OF INCHES OF SNOW MAINLY NORTH OF A PENTWATER TO
ALMA LINE.
LOW PRESSURE IN THE PLAINS WILL PUSH WARMER AIR NORTHWARD MONDAY AND
TUESDAY WHICH WILL STRENGTHEN THE BAROCLINIC ZONE OVER THE CWA. AS
THE LOW MOVES EAST...RAIN WILL DEVELOP MONDAY NIGHT AND CONTINUE
TUESDAY. MONDAY WILL BE THE WARMER OF THE TWO DAYS WITH HIGHS NEAR
60. BUT THEN THE BOUNDARY WILL SINK SOUTH AND NORTHEAST WINDS WILL
STRENGTHEN PULLING IN COOLER AIR FROM ONTARIO. MODELS INDICATE
ELEVATED INSTABILITY TUESDAY. LI/S NEAR -4C COUPLED WITH MUCAPE
500-1000 J/KG POINT TOWARD SOME THUNDERSTORMS SOUTH OF I-96. TSRA
WAS ADDED TO THE GRIDS TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 324 AM EDT SUN APR 5 2015
THE MAIN CHALLENGE IN THE LONG TERM DEALS WITH THE RISK FOR MIXED
PRECIPITATION TUESDAY NIGHT AND ALSO THE HEAVY RAIN/THUNDER RISK
GOING INTO THE END OF THE WEEK.
MODELS CONTINUE TO SHOW AN ELEVATED WARM LAYER ABOVE A NEAR FREEZING
LOW LEVEL LAYER TUESDAY NIGHT UP AROUND HARRISON AND MOUNT
PLEASANT. BASED ON THIS WILL MAINTAIN THE POSSIBILITY OF ZR MAINLY
NORTH OF A ALMA TO LUDINGTON LINE. TRENDS SEEM TO SUPPORT LESS
SHALLOW COLD AIR. TRIGGERING THE PRECIPITATION WILL BE A WARM FRONT
SITUATED OVER LOWER MI WITH THE NOSE OF A LOW LEVEL JET ACROSS THE
FRONT. WILL NEED TO MONITOR THE THUNDER RISK. HIGHEST POPS MAINLY
OVER SOUTHERN LOWER MI...CLOSER TO THE FRONT AND GULF MOISTURE.
MODELS ARE IN BETTER AGREEMENT IN DRAWING UP GULF MOISTURE THU INTO
THU NIGHT...SENDING THE WARM FRONT NORTH OF GRAND RAPIDS.
INSTABILITY ARRIVES AS WELL. ADDED THUNDER TO THE FORECAST FOR MUCH
OF THE REGION. POPS HAVE BEEN RAISED AS WELL. RAIN COULD BE HEAVY
GIVEN THE LOW LEVEL JET IN PLACE. MODELS VARY ON THE TIMING OF THE
COLD FRONTS ARRIVAL LATER THU NIGHT OR FRI. WILL HOLD OFF ON THE
THUNDER RISK FOR FRI AT THIS TIME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 705 AM EDT SUN APR 5 2015
THE BAND OF SNOW AND RAIN WITH ASSOCIATED IMPACTS WILL STAY JUST
NORTH OF KMKG...KGRR AND KLAN THROUGH EARLY THIS MORNING. THEN FOR
THE REMAINDER OF THE DAY VFR WEATHER IS FORECASTED TO PREVAIL AS
THE AIRMASS DRIES OUT. SOME GUSTY WINDS ARE POSSIBLE THIS
MORNING...MAINLY FOR KAZO...KBTL AND KJXN. VALUES OVER 20 KNOTS
POSSIBLE.
&&
.MARINE...
ISSUED AT 324 AM EDT SUN APR 5 2015
A FAIRLY QUIET DAY ON THE LAKE EXPECTED. 5 TO 15 KNOT WINDS WILL
RESULT IN WAVES 2 FEET OR LESS.
&&
.HYDROLOGY...
ISSUED AT 1220 PM EDT SUN APR 5 2015
A BAND OF 0.10 TO 0.25 INCHES OF PRECIPITATION FELL LAST NIGHT
THROUGH THIS MORNING IN THE FORM OF RAIN AND SNOW ACROSS CENTRAL
LOWER MICHIGAN. THERE WERE A FEW REPORTS OF AROUND 2 INCHES OF
SNOW ACROSS THE MUSKEGON RIVER BASIN. NOT MUCH HYDRO IMPACT
HERE...RIVERS REMAIN MOSTLY LEVEL OR RECEDING.
THE WEATHER PATTERN WILL REMAIN CONDUCIVE FOR PRECIPITATION OVER
THE NEXT WEEK. RAIN WILL DEVELOP MONDAY NIGHT AND PERSIST INTO
TUESDAY...WITH A CHANCE FOR STORMS ON TUESDAY AS WELL. THERE IS A
HIGHER RISK FOR HEAVIER RAIN AND THUNDERSTORMS ON THURSDAY. IN
GENERAL...1 TO 2 INCHES OF RAINFALL IS POSSIBLE OVER THE NEXT
WEEK. THE POTENTIAL IS CERTAINLY THERE FOR HIGHER RAINFALL AMOUNTS
WITH THUNDERSTORMS. THERE IS LOW CONFIDENCE IN FLOODING AT THIS
POINT...BUT RISES ON STREAMS AS WELL AS MAIN STEMS CAN BE
EXPECTED.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...MEADE
SYNOPSIS...04
SHORT TERM...04
LONG TERM...MJS
AVIATION...MJS
HYDROLOGY...EBW
MARINE...04
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1030 AM EDT SUN APR 5 2015
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 324 AM EDT SUN APR 5 2015
LIGHT RAIN AND SNOW WILL SPREAD EAST FROM WISCONSIN EARLY THIS
MORNING. THE SNOW MAY ACCUMULATE AN INCH OR TWO NORTH OF I-96 BEFORE
CHANGING TO RAIN BY LATE MORNING. A FRONTAL BOUNDARY WILL REMAIN
STRETCHED ACROSS LOWER MICHIGAN FOR A FEW DAYS. SEVERAL PERIODS OF
SHOWERS ARE POSSIBLE NEXT WEEK ALONG WITH A FEW THUNDERSTORMS
TUESDAY.
&&
.UPDATE...
ISSUED AT 1030 AM EDT SUN APR 5 2015
CANCELLED THE WINTER WEATHER ADVISORY NORTH OF I-96 EARLY AS
PRECIPITATION HAS DIMINISHED. THERE IS STILL A CHANCE OF SOME
ADDITIONAL PRECIPITATION NORTH OF THE FRONTAL BOUNDARY TODAY...
ALTHOUGH IT SHOULD BE MAINLY JUST LIGHT RAIN/DRIZZLE AS SFC TEMPS
ARE WARMING.
SNOWFALL REPORTS HAVE BEEN LIMITED THIS MORNING BUT WE HAVE
RECEIVED REPORTS OF AROUND 2 INCHES AT REED CITY AND BIG RAPIDS.
WE WILL HAVE TO WATCH TEMPS ALONG THE I-94 CORRIDOR THIS
AFTERNOON. THIS AREA IS SOUTH OF THE SFC BOUNDARY WHICH APPEARS TO
BE LOCATED ALONG OR JUST SOUTH OF I-96 AT 10 AM. WITH ENOUGH
SUNSHINE IT IS POSSIBLE THAT AZO/BTL/JXN COULD REACH 65. MEANWHILE
CLOUDS AND EASTERLY FLOW WILL KEEP AREAS NORTH OF I-96 STUCK IN
THE 40S.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 324 AM EDT SUN APR 5 2015
FORECAST CONCERNS DEAL WITH PCPN TRENDS THROUGH THE PERIOD.
REGIONAL RADAR SHOWS PCPN MOVING EAST FROM WISCONSIN. MUCH OF THIS
PCPN SO FAR IS GOING INTO MOISTENING THE VERY DRY LOWER LEVELS OF
THE ATMOSPHERE. HRRR CONTINUES TO SHOW LIGHT SNOW DEVELOPING OVER
THE NORTHERN HALF OF THE CWA EARLY THIS MORNING. HOWEVER SHORT RANGE
MODELS ARE NOT AS BULLISH ON QPF AND SO WE SCALED BACK ON ACCUMS.
THIS SYSTEM HAS NEVER BEEN A HIGH CONFIDENCE SYSTEM DUE TO IT/S
DEPENDENCE ON MOSTLY FRONTOGENETICAL FORCING FOR PCPN DEVELOPMENT.
WEAK LOW PRESSURE PUSHED A TROUGH SOUTH OVER THE CENTRAL CWA A FEW
HOURS AGO AND THIS BOUNDARY WILL BE THE FOCUS FOR PCPN DEVELOPMENT
OVER THE NEXT FEW DAYS. UPSTREAM RADAR SHOWS 30+ DBZ WESTWARD TO THE
MISSISSIPPI. THUS WE/LL KEEP THE WINTER WEATHER ADVISORY GOING.
SREF/HRRR INDICATE THAT THE PCPN SHOULD WIND DOWN BY LATE MORNING.
LOOKING AT A COUPLE OF INCHES OF SNOW MAINLY NORTH OF A PENTWATER TO
ALMA LINE.
LOW PRESSURE IN THE PLAINS WILL PUSH WARMER AIR NORTHWARD MONDAY AND
TUESDAY WHICH WILL STRENGTHEN THE BAROCLINIC ZONE OVER THE CWA. AS
THE LOW MOVES EAST...RAIN WILL DEVELOP MONDAY NIGHT AND CONTINUE
TUESDAY. MONDAY WILL BE THE WARMER OF THE TWO DAYS WITH HIGHS NEAR
60. BUT THEN THE BOUNDARY WILL SINK SOUTH AND NORTHEAST WINDS WILL
STRENGTHEN PULLING IN COOLER AIR FROM ONTARIO. MODELS INDICATE
ELEVATED INSTABILITY TUESDAY. LI/S NEAR -4C COUPLED WITH MUCAPE
500-1000 J/KG POINT TOWARD SOME THUNDERSTORMS SOUTH OF I-96. TSRA
WAS ADDED TO THE GRIDS TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 324 AM EDT SUN APR 5 2015
THE MAIN CHALLENGE IN THE LONG TERM DEALS WITH THE RISK FOR MIXED
PRECIPITATION TUESDAY NIGHT AND ALSO THE HEAVY RAIN/THUNDER RISK
GOING INTO THE END OF THE WEEK.
MODELS CONTINUE TO SHOW AN ELEVATED WARM LAYER ABOVE A NEAR FREEZING
LOW LEVEL LAYER TUESDAY NIGHT UP AROUND HARRISON AND MOUNT
PLEASANT. BASED ON THIS WILL MAINTAIN THE POSSIBILITY OF ZR MAINLY
NORTH OF A ALMA TO LUDINGTON LINE. TRENDS SEEM TO SUPPORT LESS
SHALLOW COLD AIR. TRIGGERING THE PRECIPITATION WILL BE A WARM FRONT
SITUATED OVER LOWER MI WITH THE NOSE OF A LOW LEVEL JET ACROSS THE
FRONT. WILL NEED TO MONITOR THE THUNDER RISK. HIGHEST POPS MAINLY
OVER SOUTHERN LOWER MI...CLOSER TO THE FRONT AND GULF MOISTURE.
MODELS ARE IN BETTER AGREEMENT IN DRAWING UP GULF MOISTURE THU INTO
THU NIGHT...SENDING THE WARM FRONT NORTH OF GRAND RAPIDS.
INSTABILITY ARRIVES AS WELL. ADDED THUNDER TO THE FORECAST FOR MUCH
OF THE REGION. POPS HAVE BEEN RAISED AS WELL. RAIN COULD BE HEAVY
GIVEN THE LOW LEVEL JET IN PLACE. MODELS VARY ON THE TIMING OF THE
COLD FRONTS ARRIVAL LATER THU NIGHT OR FRI. WILL HOLD OFF ON THE
THUNDER RISK FOR FRI AT THIS TIME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 705 AM EDT SUN APR 5 2015
THE BAND OF SNOW AND RAIN WITH ASSOCIATED IMPACTS WILL STAY JUST
NORTH OF KMKG...KGRR AND KLAN THROUGH EARLY THIS MORNING. THEN FOR
THE REMAINDER OF THE DAY VFR WEATHER IS FORECASTED TO PREVAIL AS
THE AIRMASS DRIES OUT. SOME GUSTY WINDS ARE POSSIBLE THIS
MORNING...MAINLY FOR KAZO...KBTL AND KJXN. VALUES OVER 20 KNOTS
POSSIBLE.
&&
.MARINE...
ISSUED AT 324 AM EDT SUN APR 5 2015
A FAIRLY QUIET DAY ON THE LAKE EXPECTED. 5 TO 15 KNOT WINDS WILL
RESULT IN WAVES 2 FEET OR LESS.
&&
.HYDROLOGY...
ISSUED AT 330 PM EDT SAT APR 4 2015
AROUND A QUARTER INCH OF PRECIPITATION IS EXPECTED LATE TONIGHT
THROUGH SUNDAY ACROSS CENTRAL LOWER MICHIGAN...MAINLY IN THE FORM OF
SNOW. A FAIRLY NARROW BAND OF HIGHER QPF AMOUNTS IS POSSIBLE UP TO
AROUND HALF AN INCH. THIS ONE EVENT WILL NOT HAVE A HUGE IMPACT ON
AREA RIVERS...BUT THE PATTERN OVER THE NEXT WEEK IS SHAPING UP TO BE
A WET ONE. THERE WILL BE SEVERAL CHANCES FOR PRECIPITATION OVER THE
NEXT WEEK. RIVER STREAMFLOW PERCENTILE IS CURRENTLY NEAR TO SLIGHTLY
BELOW NORMAL...BUT SOME RIVERS MAY MAKE A RUN AT BANKFULL OVER THE
NEXT WEEK. WPC 7-DAY QPF INDICATES THE KALAMAZOO BASIN AND
HEADWATERS OF THE GRAND COULD SEE IN EXCESS OF AN INCH AND A HALF.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...MEADE
SYNOPSIS...04
SHORT TERM...04
LONG TERM...MJS
AVIATION...MJS
HYDROLOGY...EBW
MARINE...04
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
723 AM EDT SUN APR 5 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM EDT SUN APR 5 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A CONFLUENT NW
FLOW ALOFT OVER THE UPPER GRT LKS BTWN CUTOFF H5 LO OVER NRN QUEBEC
AND POLAR/SUBTROPICAL BRANCH RDG OVER THE ROCKIES. SPRAWLING SFC HI
PRES IS CENTERED OVER MANITOBA...WITH A RDG AXIS ORIENTED SE INTO LK
SUP. THE UPSTREAM 00Z RAOBS SHOW A VERY DRY AIRMASS ASSOCIATED WITH
THIS HI. THE 00Z PWAT WAS 0.13 INCH AT INL /45 PCT OF NORMAL/ AND
ONLY 0.05 INCH AT YPL AND THE PAS MANITOBA. THERE ARE SOME CLDS OVER
THE FAR SCENTRAL CLOSER TO H85 WARM FNT DRAPED W-E ACROSS THE UPR
MIDWEST. THERE ARE SOME SCT MID CLDS OVER THE REST OF THE CWA
ASSOCIATED WITH A WEAK SHRTWV THAT IS SHEARING OUT IN THE NW UPPER
FLOW AND ACCOMPANYING LO PRES TROF. SOME LO CLDS AND EVEN A FEW
FLURRIES HAVE ALSO DVLPD OVER THE NCENTRAL WITH UPSLOPE NE FLOW
ASSOCIATED WITH PASSAGE OF THE LO PRES TROF. TEMPS TO THE N ARE
QUITE CHILLY AS WELL...WITH 00Z H85 TEMP -20C AT YPL. LOOKING TO THE
S...THERE IS A BAND OF SOME RAIN SHOWERS STRETCHING FM SRN MN ACROSS
CENTRAL WI ASSOCIATED WITH APRCH OF ANOTHER WEAK SHRTWV AND SOME
WAA/FGEN TO THE NE OF THE H85 WARM FNT. LOOKING UPSTREAM...THERE IS
A SHRTWV IN THE POLAR BRANCH FLOW RIDING OVER THE ROCKIES RDG. HI
CLDS IN ADVANCE OF THIS FEATURE ARE MOVING THRU THE NRN PLAINS. SOME
LIGHT RA IS FALLING ALONG THE NDAKOTA/SDAKOTA BORDER DESPITE VERY
DRY LLVLS SHOWN ON THE 00Z BISMARCK RAOB.
MAIN FCST CONCERNS IN THE SHORT TERM WL FOCUS ON CLDS TODAY AND THEN
POPS/SN AMOUNTS FOR TNGT ASSOCIATED WITH SHRTWV NOW RIDING OVER THE
ROCKIES RDG AND INTO THE NRN PLAINS.
TDAY...AS WEAK SHRTWV CAUSING BAND OF PCPN IN CENTRAL WI SLIDES TO
THE ESE...THIS AREA OF PCPN WL REMAIN S OF UPR MI. OTHERWISE...MID
LVL SUBSIDENCE/HI PRES BLDG OVER LK SUP WL BRING MAINLY DRY WX.
SEVERAL OF THE HIER RES MODELS INDICATE SOME LO CLDS WL PERSIST AT
LEAST FOR A PORTION OF THIS MRNG OVER MAINLY THE NCNTRL CWA WITH
LIGHT UPSLOPE ENE WIND THAT WL SLOW THE ADVECTION OF THE VERY DRY AIR
SHOWN IN ONTARIO. ALSO ADDED SOME FLURRIES THIS MRNG IN THE UPSLOPE
AREAS OF THE NCENTRAL. WITH AN ENE WIND...EXPECT BLO NORMAL
TEMPS...ESPECIALLY NEAR THE CHILLY WATERS OF THE GREAT LKS. DEEPER
MIXING TO H8 AS OBSVD ON THE 00Z INL RAOB WL ALLOW TEMPS NEAR THE WI
BORDER TO REACH THE LO 40S AWAY FM ANY LK MODERATION AND DESPITE SOME
INCRSG HI CLDS THIS AFTN.
TNGT...MODELS INDICATE UPR CONFLUENCE ZN WL RETREAT TO THE N...
ALLOWING SHRTWV NOW MOVING INTO THE NRN PLAINS TO APRCH. WITH THE
RETREAT OF THE CONFLUENCE ZN...UPR MI IS PROGGED TO FALL INTO THE
RRQ OF 120KT H3 JET MAX THAT IS FCST TO SHIFT AVER FAR SW QUEBEC/
ADJOINING ONTARIO OVERNGT. AS THE H85 WARM FNT/MID LVL FGEN BAND
SHIFT TO THE N UNDER THE DVLPG UPR DVGC IN THE RRQ OF THE JET
STREAK...A BAND OF WAA SN TO THE N OF THE WARM FNT IS PROGGED TO
DEVELOP NEAR THE WI BORDER IN THE EVNG AND DRIFT SLOWLY TO THE N
THRU THE N...ENVELOPING ALL BUT THE KEWEENAW PENINSULA BY 12Z MON.
SOME OF THE MODELS SHOW AS MUCH AS 0.25 TO 0.30 INCH QPF OVER THE
SCENTRAL...IN GOOD AGREEMENT WITH H7 SPECIFIC HUMIDITY FCST IN THE
2.5-3.0 G/KG RANGE. NOT OUT OF THE QUESTION WET SN ACCUMS WITH
NARROW/HIER DGZ MAY APRCH ADVY CRITERIA OVER PORTIONS OF THE
SCENTRAL.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 345 AM EDT SUN APR 5 2015
THE UPPER LOW SPINNING OFF THE PACIFIC NORTHWEST WILL DROP SOUTH
ALONG THE WEST COAST OF THE CONUS OVER THE NEXT COUPLE
DAYS...LEADING TO A TRANSITION TO THE WEATHER PATTERN AWAY FROM
NORTHWESTERLY FLOW ALOFT TO A WESTERLY FLOW BY MID WEEK. WHILE THAT
OCCURS...SEVERAL WAVES WILL EJECT TOWARDS THE AREA AND ALONG A
NEARLY STATIONARY WARM FRONT STRETCHING FROM A LOW IN THE LEE OF THE
CENTRAL ROCKIES THROUGH THE LOWER GREAT LAKES. THAT FRONT WILL SHIFT
NORTH SLIGHTLY LATER TONIGHT AND REMAIN THROUGH TUESDAY AS THE HIGH
PRESSURE RIDGE THAT IS OVER THE AREA AT THE PRESENT TIME SHIFTS
NORTH INTO CANADA. THAT WILL BE THE FIRST POTENTIAL FOR
PRECIPITATION FOR THE CWA. WHILE THERE HAVE BEEN SOME VARIATIONS IN
THE MODEL SOLUTIONS ON THIS NORTHWARD SHIFT OF THE WARM FRONT AND
ASSOCIATED PRECIPITATION...THEY SEEM TO HAVE NARROWED IN ON THE
FOCUS OF THE BEST PRECIPITATION LATE TONIGHT INTO TUESDAY BEING OVER
NORTHERN WISCONSIN AND SOUTHERN UPPER MICHIGAN. DURING THAT
TIME...THINK THE HEAVIEST PRECIPITATION WILL OCCUR WITH THE INITIAL
NORTHWARD PUSH LATE TONIGHT INTO MONDAY MORNING BEFORE THE WESTERLY
MID LEVEL FLOW GENERALLY BECOMES PARALLEL TO THE ISOTHERMS MONDAY
AFTERNOON. DURING THAT BETTER PRECIPITATION...THE THERMAL PROFILE
LOOKS TO STAY BELOW FREEZING AND WOULD EXPECT THE P-TYPE TO REMAIN
AS SNOW. BUT AS THE FORCING WEAKENS DURING THE DAY...THERE ARE HINTS
THAT THE MOISTURE IN THE ICE CRYSTAL REGION WILL CUT OUT AND THE SUB
800MB THERMAL PROFILE IS HOVERING AT OR JUST BELOW FREEZING. THAT
WOULD LEAD TO RAIN/DRIZZLE AND POTENTIAL FOR FZRA WHERE TEMPS ARE
AROUND FREEZING. UNFORTUNATELY CONFIDENCE IS TOO LOW TO GET OVERLY
DETAILED AT THIS POINT...BUT WILL SHOW A MENTION OF RAIN WITH THE
SNOW TO ACCOUNT FOR THE DRYING ALOFT. FORCING DURING MONDAY
AFTERNOON WEAKENS AND REMAINS PINNED ALONG THE WISCONSIN BORDER AND
THROUGH THE SOUTHERN U.P. BEFORE WINDS BACK SLIGHTLY MONDAY NIGHT AS
ANOTHER SHORTWAVE SLIDES THROUGH THE REGION. THUS...WOULD EXPECT
ANOTHER UPTICK IN PRECIPITATION ON MONDAY NIGHT...BUT STILL NEAR THE
WI BORDER AND THE SOUTHERN U.P. LIKE MONDAY AFTERNOON. THE SHORTWAVE
DOES HELP TO BRING ADDITIONAL MOISTURE INTO THE ICE CRYSTAL REGION
FOR PORTIONS OF THE CWA (MAINLY NORTHERN HALF TO 2/3RDS)...BUT THE
MAIN FORCING/MOISTURE IS BELOW THE FAVORED ICE CRYSTAL REGION.
THUS..WOULD EXPECT THE PRECIPITATION TO SOME LIQUID IN IT OVER THE
SOUTH CENTRAL...THEN CHANGING TO ALL SNOW AS YOU HEAD NORTH ACROSS
THE U.P. THEREFORE...THE SURFACE TEMPERATURES WILL LARGELY DETERMINE
THE IMPACT FROM THIS PRECIPITATION MONDAY AFTERNOON INTO TUESDAY
MORNING. WITH THE LOW LEVEL FLOW OUT OF THE NORTHEAST KEEPING COLDER
AIR FILTERING INTO THE AREA...WOULD EXPECT PERIODS OF FREEZING RAIN.
THINK THERE WILL BE ENOUGH WARMING ON MONDAY AFTERNOON TO LIMIT THE
POTENTIAL (EXCEPT ON EXISTING COLD SURFACES)...BUT COOLING MONDAY
NIGHT AND REMAINING INTO TUESDAY WOULD SUPPORT FREEZING RAIN WHERE
THE LIQUID PRECIPITATION OCCURS OVER THE SOUTH CENTRAL. THE SNOW
WILL BE DIMINISH MONDAY MORNING...LIMITING ADDITIONAL
ACCUMULATION...BUT IT STILL LOOKS LIKE SOME LOCATIONS IN SOUTHERN
MENOMINEE COUNTY WILL EXCEED 3 INCHES LATE TONIGHT INTO MONDAY
MORNING. THEN FOR MONDAY NIGHT...EXPECT A DUSTING TO 1.5IN OVER THE
INTERIOR WEST AND CENTRAL.
AS THE SURFACE HIGH NEAR JAMES BAY STRENGTHENS ON TUESDAY
AFTERNOON...EXPECT A HIGH PRESSURE RIDGE TO NOSE BACK SOUTH AND INTO
THE UPPER GREAT LAKES REGION FOR TUESDAY NIGHT INTO WEDNESDAY
EVENING. THIS WILL LEAD TO A DRY PERIOD OVER UPPER MICHIGAN BEFORE
THE NEXT WAVE ARRIVES FOR THE LATER PART OF THE WORK WEEK.
THAT NEXT WAVE IS TIED TO THE UPPER LOW ALONG THE WEST COAST OVER
THE NEXT COUPLE DAYS MOVING THROUGH THE ROCKIES DURING THE MIDDLE OF
THE WEEK AND THEN LIFTING NORTHEAST THROUGH THE GREAT LAKES REGION
THURSDAY-SATURDAY. THIS WILL LEAD TO SEVERAL WAVES OF PRECIPITATION
DURING THAT PERIOD. WON/T GET TOO SPECIFIC IN THE GRIDS DUE TO THE
EVOLVING IDEAS IN THE MODELS...BUT THE FIRST WAVE WILL MOVE THROUGH
ON THURSDAY OUT AHEAD OF THE UPPER LOW. WITH THE WARMING BETWEEN 925-
700MB (PEAKING BETWEEN 1 AND 6C)...WILL SEE THE PRECIPITATION FALL
AS A MIX OR ALL LIQUID. BUT WITH SURFACE TEMPERATURES STILL STAYING
AT OR AROUND FREEZING WITH THE LOW LEVEL EASTERLY FLOW FROM THE
DEPARTING HIGH...WILL CONTINUE TO MENTION A FREEZING RAIN POTENTIAL
FOR THURSDAY MORNING. EXPECT A BRIEF LULL BEHIND THAT FIRST WAVE
BEFORE THE MAIN PRECIPITATION ASSOCIATED WITH THE UPPER LOW LIFTS
NORTHEAST INTO THE GREAT LAKES REGION FOR THE FRIDAY INTO SATURDAY
PERIOD. DIFFERENCES IN THE SPEED OF THE MODELS...AS WELL AS THE
UPPER LOW TRACK...AS IT MOVES THROUGH THE REGION LEADS TO
UNCERTAINTY ON THE PRECIP TYPES. WOULD EXPECT THERE TO BE ENOUGH
WARM AIR TO SUPPORT RAIN FOR MUCH OF FRIDAY (ALTHOUGH THERE COULD BE
SOME FZRA IF IT STARTS EARLY ENOUGH FRIDAY MORNING) BEFORE POSSIBLY
MIXING WITH SNOW FRIDAY NIGHT INTO SATURDAY. THE 00Z GFS CONTINUES
TO BE MUCH FASTER WITH THE LOW MOVING THROUGH AND HAS SHIFTED IT
SIGNIFICANTLY FARTHER TO THE SOUTHEAST...LEADING TO A BETTER
OPPORTUNITY FOR SNOW. LOOKING AT THE 12Z ECMWF ENSEMBLE
MEMBERS...THAT FASTER TREND SEEMS A LITTLE AGGRESSIVE ALTHOUGH THE
SOUTHEAST MOVEMENT IS POSSIBLE WITH SOME ECMWF ENSEMBLE MEMBERS
TRACKING THE LOW THROUGH NORTHERN LOWER MICHIGAN. ALL IN ALL...WITH
THIS PERIOD STILL SEVERAL DAYS OUT...WON/T GET TOO DETAILED AND SHOW
THE GENERAL IDEA FOR POPS AND P-TYPE.
FINALLY...EXPECT TO SEE GRADUALLY WARMING TEMPS THROUGH THE WEEK AS
THE COLD AIR RETREATS TO THE NORTH BUT STILL STAYING AROUND OR BELOW
NORMAL FOR HIGHS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 722 AM EDT SUN APR 5 2015
AN UPSLOPE ENE WIND WITH SOME MOISTENING OFF LK SUP WL RESULT IN
MVFR CONDITIONS AT SAW INTO EARLY THIS AFTN. SINCE THE LLVL AIRMASS
AT CMX IS MUCH DRIER AND THERE IS AN ABSENCE OF UPSLOPE FLOW INTO
IWD...THESE LOCATIONS SHOULD SEE VFR WX. THICKENING HIER CLDS WL
ARRIVE LATER TODAY/THIS EVNG IN ADVANCE OF ANOTHER DISTURBANCE AND
SLOWLY APRCHG WARM FNT. SN IN ADVANCE OF THESE FEATURES WL
OVERSPREAD IWD AND SAW OVERNGT...WITH MVFR CONDITIONS EXPECTED. IF
THE SN BAND EDGES FARTHER TO THE N...IFR CIGS AND/OR VSBY MAY OCCUR
AT THESE SITES. THE BULK OF THE PCPN IS LIKELY TO STAY S OF CMX AND
THE DRIER AIR THERE...SO EXPECT VFR CONDITIONS TO LINGER THERE THRU
06/12Z.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 345 AM EDT SUN APR 5 2015
WITH THE UPPER GREAT LAKES REGION BETWEEN A HIGH IN SOUTHERN CANADA
AND A WARM FRONT STRETCHING EAST ACROSS THE LOWER GREAT
LAKES...EXPECT PERSISTENT NORTHEAST TO EASTERLY WINDS THROUGH THE
MIDDLE OF THE WORK WEEK. MOST OF THE TIME WINDS WILL STAY BELOW
25KTS...BUT FUNNELING DOWN WESTERN LAKE SUPERIOR COULD LEAD TO GUSTS
UP TO 30KTS LATE MONDAY NIGHT INTO TUESDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...KC
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
709 AM EDT SUN APR 5 2015
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 324 AM EDT SUN APR 5 2015
LIGHT RAIN AND SNOW WILL SPREAD EAST FROM WISCONSIN EARLY THIS
MORNING. THE SNOW MAY ACCUMULATE AN INCH OR TWO NORTH OF I-96 BEFORE
CHANGING TO RAIN BY LATE MORNING. A FRONTAL BOUNDARY WILL REMAIN
STRETCHED ACROSS LOWER MICHIGAN FOR A FEW DAYS. SEVERAL PERIODS OF
SHOWERS ARE POSSIBLE NEXT WEEK ALONG WITH A FEW THUNDERSTORMS
TUESDAY.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 324 AM EDT SUN APR 5 2015
FORECAST CONCERNS DEAL WITH PCPN TRENDS THROUGH THE PERIOD.
REGIONAL RADAR SHOWS PCPN MOVING EAST FROM WISCONSIN. MUCH OF THIS
PCPN SO FAR IS GOING INTO MOISTENING THE VERY DRY LOWER LEVELS OF
THE ATMOSPHERE. HRRR CONTINUES TO SHOW LIGHT SNOW DEVELOPING OVER
THE NORTHERN HALF OF THE CWA EARLY THIS MORNING. HOWEVER SHORT RANGE
MODELS ARE NOT AS BULLISH ON QPF AND SO WE SCALED BACK ON ACCUMS.
THIS SYSTEM HAS NEVER BEEN A HIGH CONFIDENCE SYSTEM DUE TO IT/S
DEPENDENCE ON MOSTLY FRONTOGENETICAL FORCING FOR PCPN DEVELOPMENT.
WEAK LOW PRESSURE PUSHED A TROUGH SOUTH OVER THE CENTRAL CWA A FEW
HOURS AGO AND THIS BOUNDARY WILL BE THE FOCUS FOR PCPN DEVELOPMENT
OVER THE NEXT FEW DAYS. UPSTREAM RADAR SHOWS 30+ DBZ WESTWARD TO THE
MISSISSIPPI. THUS WE/LL KEEP THE WINTER WEATHER ADVISORY GOING.
SREF/HRRR INDICATE THAT THE PCPN SHOULD WIND DOWN BY LATE MORNING.
LOOKING AT A COUPLE OF INCHES OF SNOW MAINLY NORTH OF A PENTWATER TO
ALMA LINE.
LOW PRESSURE IN THE PLAINS WILL PUSH WARMER AIR NORTHWARD MONDAY AND
TUESDAY WHICH WILL STRENGTHEN THE BAROCLINIC ZONE OVER THE CWA. AS
THE LOW MOVES EAST...RAIN WILL DEVELOP MONDAY NIGHT AND CONTINUE
TUESDAY. MONDAY WILL BE THE WARMER OF THE TWO DAYS WITH HIGHS NEAR
60. BUT THEN THE BOUNDARY WILL SINK SOUTH AND NORTHEAST WINDS WILL
STRENGTHEN PULLING IN COOLER AIR FROM ONTARIO. MODELS INDICATE
ELEVATED INSTABILITY TUESDAY. LI/S NEAR -4C COUPLED WITH MUCAPE
500-1000 J/KG POINT TOWARD SOME THUNDERSTORMS SOUTH OF I-96. TSRA
WAS ADDED TO THE GRIDS TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 324 AM EDT SUN APR 5 2015
THE MAIN CHALLENGE IN THE LONG TERM DEALS WITH THE RISK FOR MIXED
PRECIPITATION TUESDAY NIGHT AND ALSO THE HEAVY RAIN/THUNDER RISK
GOING INTO THE END OF THE WEEK.
MODELS CONTINUE TO SHOW AN ELEVATED WARM LAYER ABOVE A NEAR FREEZING
LOW LEVEL LAYER TUESDAY NIGHT UP AROUND HARRISON AND MOUNT
PLEASANT. BASED ON THIS WILL MAINTAIN THE POSSIBILITY OF ZR MAINLY
NORTH OF A ALMA TO LUDINGTON LINE. TRENDS SEEM TO SUPPORT LESS
SHALLOW COLD AIR. TRIGGERING THE PRECIPITATION WILL BE A WARM FRONT
SITUATED OVER LOWER MI WITH THE NOSE OF A LOW LEVEL JET ACROSS THE
FRONT. WILL NEED TO MONITOR THE THUNDER RISK. HIGHEST POPS MAINLY
OVER SOUTHERN LOWER MI...CLOSER TO THE FRONT AND GULF MOISTURE.
MODELS ARE IN BETTER AGREEMENT IN DRAWING UP GULF MOISTURE THU INTO
THU NIGHT...SENDING THE WARM FRONT NORTH OF GRAND RAPIDS.
INSTABILITY ARRIVES AS WELL. ADDED THUNDER TO THE FORECAST FOR MUCH
OF THE REGION. POPS HAVE BEEN RAISED AS WELL. RAIN COULD BE HEAVY
GIVEN THE LOW LEVEL JET IN PLACE. MODELS VARY ON THE TIMING OF THE
COLD FRONTS ARRIVAL LATER THU NIGHT OR FRI. WILL HOLD OFF ON THE
THUNDER RISK FOR FRI AT THIS TIME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 705 AM EDT SUN APR 5 2015
THE BAND OF SNOW AND RAIN WITH ASSOCIATED IMPACTS WILL STAY JUST
NORTH OF KMKG...KGRR AND KLAN THROUGH EARLY THIS MORNING. THEN FOR
THE REMAINDER OF THE DAY VFR WEATHER IS FORECASTED TO PREVAIL AS
THE AIRMASS DRIES OUT. SOME GUSTY WINDS ARE POSSIBLE THIS
MORNING...MAINLY FOR KAZO...KBTL AND KJXN. VALUES OVER 20 KNOTS
POSSIBLE.
&&
.MARINE...
ISSUED AT 324 AM EDT SUN APR 5 2015
A FAIRLY QUIET DAY ON THE LAKE EXPECTED. 5 TO 15 KNOT WINDS WILL
RESULT IN WAVES 2 FEET OR LESS.
&&
.HYDROLOGY...
ISSUED AT 330 PM EDT SAT APR 4 2015
AROUND A QUARTER INCH OF PRECIPITATION IS EXPECTED LATE TONIGHT
THROUGH SUNDAY ACROSS CENTRAL LOWER MICHIGAN...MAINLY IN THE FORM OF
SNOW. A FAIRLY NARROW BAND OF HIGHER QPF AMOUNTS IS POSSIBLE UP TO
AROUND HALF AN INCH. THIS ONE EVENT WILL NOT HAVE A HUGE IMPACT ON
AREA RIVERS...BUT THE PATTERN OVER THE NEXT WEEK IS SHAPING UP TO BE
A WET ONE. THERE WILL BE SEVERAL CHANCES FOR PRECIPITATION OVER THE
NEXT WEEK. RIVER STREAMFLOW PERCENTILE IS CURRENTLY NEAR TO SLIGHTLY
BELOW NORMAL...BUT SOME RIVERS MAY MAKE A RUN AT BANKFULL OVER THE
NEXT WEEK. WPC 7-DAY QPF INDICATES THE KALAMAZOO BASIN AND
HEADWATERS OF THE GRAND COULD SEE IN EXCESS OF AN INCH AND A HALF.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL NOON EDT TODAY FOR MIZ037>040-
043>046-051-052.
LM...NONE.
&&
$$
SYNOPSIS...04
SHORT TERM...04
LONG TERM...MJS
AVIATION...MJS
HYDROLOGY...EBW
MARINE...04
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
404 AM EDT SUN APR 5 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM EDT SUN APR 5 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A CONFLUENT NW
FLOW ALOFT OVER THE UPPER GRT LKS BTWN CUTOFF H5 LO OVER NRN QUEBEC
AND POLAR/SUBTROPICAL BRANCH RDG OVER THE ROCKIES. SPRAWLING SFC HI
PRES IS CENTERED OVER MANITOBA...WITH A RDG AXIS ORIENTED SE INTO LK
SUP. THE UPSTREAM 00Z RAOBS SHOW A VERY DRY AIRMASS ASSOCIATED WITH
THIS HI. THE 00Z PWAT WAS 0.13 INCH AT INL /45 PCT OF NORMAL/ AND
ONLY 0.05 INCH AT YPL AND THE PAS MANITOBA. THERE ARE SOME CLDS OVER
THE FAR SCENTRAL CLOSER TO H85 WARM FNT DRAPED W-E ACROSS THE UPR
MIDWEST. THERE ARE SOME SCT MID CLDS OVER THE REST OF THE CWA
ASSOCIATED WITH A WEAK SHRTWV THAT IS SHEARING OUT IN THE NW UPPER
FLOW AND ACCOMPANYING LO PRES TROF. SOME LO CLDS AND EVEN A FEW
FLURRIES HAVE ALSO DVLPD OVER THE NCENTRAL WITH UPSLOPE NE FLOW
ASSOCIATED WITH PASSAGE OF THE LO PRES TROF. TEMPS TO THE N ARE
QUITE CHILLY AS WELL...WITH 00Z H85 TEMP -20C AT YPL. LOOKING TO THE
S...THERE IS A BAND OF SOME RAIN SHOWERS STRETCHING FM SRN MN ACROSS
CENTRAL WI ASSOCIATED WITH APRCH OF ANOTHER WEAK SHRTWV AND SOME
WAA/FGEN TO THE NE OF THE H85 WARM FNT. LOOKING UPSTREAM...THERE IS
A SHRTWV IN THE POLAR BRANCH FLOW RIDING OVER THE ROCKIES RDG. HI
CLDS IN ADVANCE OF THIS FEATURE ARE MOVING THRU THE NRN PLAINS. SOME
LIGHT RA IS FALLING ALONG THE NDAKOTA/SDAKOTA BORDER DESPITE VERY
DRY LLVLS SHOWN ON THE 00Z BISMARCK RAOB.
MAIN FCST CONCERNS IN THE SHORT TERM WL FOCUS ON CLDS TODAY AND THEN
POPS/SN AMOUNTS FOR TNGT ASSOCIATED WITH SHRTWV NOW RIDING OVER THE
ROCKIES RDG AND INTO THE NRN PLAINS.
TDAY...AS WEAK SHRTWV CAUSING BAND OF PCPN IN CENTRAL WI SLIDES TO
THE ESE...THIS AREA OF PCPN WL REMAIN S OF UPR MI. OTHERWISE...MID
LVL SUBSIDENCE/HI PRES BLDG OVER LK SUP WL BRING MAINLY DRY WX.
SEVERAL OF THE HIER RES MODELS INDICATE SOME LO CLDS WL PERSIST AT
LEAST FOR A PORTION OF THIS MRNG OVER MAINLY THE NCNTRL CWA WITH
LIGHT UPSLOPE ENE WIND THAT WL SLOW THE ADVECTION OF THE VERY DRY AIR
SHOWN IN ONTARIO. ALSO ADDED SOME FLURRIES THIS MRNG IN THE UPSLOPE
AREAS OF THE NCENTRAL. WITH AN ENE WIND...EXPECT BLO NORMAL
TEMPS...ESPECIALLY NEAR THE CHILLY WATERS OF THE GREAT LKS. DEEPER
MIXING TO H8 AS OBSVD ON THE 00Z INL RAOB WL ALLOW TEMPS NEAR THE WI
BORDER TO REACH THE LO 40S AWAY FM ANY LK MODERATION AND DESPITE SOME
INCRSG HI CLDS THIS AFTN.
TNGT...MODELS INDICATE UPR CONFLUENCE ZN WL RETREAT TO THE N...
ALLOWING SHRTWV NOW MOVING INTO THE NRN PLAINS TO APRCH. WITH THE
RETREAT OF THE CONFLUENCE ZN...UPR MI IS PROGGED TO FALL INTO THE
RRQ OF 120KT H3 JET MAX THAT IS FCST TO SHIFT AVER FAR SW QUEBEC/
ADJOINING ONTARIO OVERNGT. AS THE H85 WARM FNT/MID LVL FGEN BAND
SHIFT TO THE N UNDER THE DVLPG UPR DVGC IN THE RRQ OF THE JET
STREAK...A BAND OF WAA SN TO THE N OF THE WARM FNT IS PROGGED TO
DEVELOP NEAR THE WI BORDER IN THE EVNG AND DRIFT SLOWLY TO THE N
THRU THE N...ENVELOPING ALL BUT THE KEWEENAW PENINSULA BY 12Z MON.
SOME OF THE MODELS SHOW AS MUCH AS 0.25 TO 0.30 INCH QPF OVER THE
SCENTRAL...IN GOOD AGREEMENT WITH H7 SPECIFIC HUMIDITY FCST IN THE
2.5-3.0 G/KG RANGE. NOT OUT OF THE QUESTION WET SN ACCUMS WITH
NARROW/HIER DGZ MAY APRCH ADVY CRITERIA OVER PORTIONS OF THE
SCENTRAL.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 345 AM EDT SUN APR 5 2015
THE UPPER LOW SPINNING OFF THE PACIFIC NORTHWEST WILL DROP SOUTH
ALONG THE WEST COAST OF THE CONUS OVER THE NEXT COUPLE
DAYS...LEADING TO A TRANSITION TO THE WEATHER PATTERN AWAY FROM
NORTHWESTERLY FLOW ALOFT TO A WESTERLY FLOW BY MID WEEK. WHILE THAT
OCCURS...SEVERAL WAVES WILL EJECT TOWARDS THE AREA AND ALONG A
NEARLY STATIONARY WARM FRONT STRETCHING FROM A LOW IN THE LEE OF THE
CENTRAL ROCKIES THROUGH THE LOWER GREAT LAKES. THAT FRONT WILL SHIFT
NORTH SLIGHTLY LATER TONIGHT AND REMAIN THROUGH TUESDAY AS THE HIGH
PRESSURE RIDGE THAT IS OVER THE AREA AT THE PRESENT TIME SHIFTS
NORTH INTO CANADA. THAT WILL BE THE FIRST POTENTIAL FOR
PRECIPITATION FOR THE CWA. WHILE THERE HAVE BEEN SOME VARIATIONS IN
THE MODEL SOLUTIONS ON THIS NORTHWARD SHIFT OF THE WARM FRONT AND
ASSOCIATED PRECIPITATION...THEY SEEM TO HAVE NARROWED IN ON THE
FOCUS OF THE BEST PRECIPITATION LATE TONIGHT INTO TUESDAY BEING OVER
NORTHERN WISCONSIN AND SOUTHERN UPPER MICHIGAN. DURING THAT
TIME...THINK THE HEAVIEST PRECIPITATION WILL OCCUR WITH THE INITIAL
NORTHWARD PUSH LATE TONIGHT INTO MONDAY MORNING BEFORE THE WESTERLY
MID LEVEL FLOW GENERALLY BECOMES PARALLEL TO THE ISOTHERMS MONDAY
AFTERNOON. DURING THAT BETTER PRECIPITATION...THE THERMAL PROFILE
LOOKS TO STAY BELOW FREEZING AND WOULD EXPECT THE P-TYPE TO REMAIN
AS SNOW. BUT AS THE FORCING WEAKENS DURING THE DAY...THERE ARE HINTS
THAT THE MOISTURE IN THE ICE CRYSTAL REGION WILL CUT OUT AND THE SUB
800MB THERMAL PROFILE IS HOVERING AT OR JUST BELOW FREEZING. THAT
WOULD LEAD TO RAIN/DRIZZLE AND POTENTIAL FOR FZRA WHERE TEMPS ARE
AROUND FREEZING. UNFORTUNATELY CONFIDENCE IS TOO LOW TO GET OVERLY
DETAILED AT THIS POINT...BUT WILL SHOW A MENTION OF RAIN WITH THE
SNOW TO ACCOUNT FOR THE DRYING ALOFT. FORCING DURING MONDAY
AFTERNOON WEAKENS AND REMAINS PINNED ALONG THE WISCONSIN BORDER AND
THROUGH THE SOUTHERN U.P. BEFORE WINDS BACK SLIGHTLY MONDAY NIGHT AS
ANOTHER SHORTWAVE SLIDES THROUGH THE REGION. THUS...WOULD EXPECT
ANOTHER UPTICK IN PRECIPITATION ON MONDAY NIGHT...BUT STILL NEAR THE
WI BORDER AND THE SOUTHERN U.P. LIKE MONDAY AFTERNOON. THE SHORTWAVE
DOES HELP TO BRING ADDITIONAL MOISTURE INTO THE ICE CRYSTAL REGION
FOR PORTIONS OF THE CWA (MAINLY NORTHERN HALF TO 2/3RDS)...BUT THE
MAIN FORCING/MOISTURE IS BELOW THE FAVORED ICE CRYSTAL REGION.
THUS..WOULD EXPECT THE PRECIPITATION TO SOME LIQUID IN IT OVER THE
SOUTH CENTRAL...THEN CHANGING TO ALL SNOW AS YOU HEAD NORTH ACROSS
THE U.P. THEREFORE...THE SURFACE TEMPERATURES WILL LARGELY DETERMINE
THE IMPACT FROM THIS PRECIPITATION MONDAY AFTERNOON INTO TUESDAY
MORNING. WITH THE LOW LEVEL FLOW OUT OF THE NORTHEAST KEEPING COLDER
AIR FILTERING INTO THE AREA...WOULD EXPECT PERIODS OF FREEZING RAIN.
THINK THERE WILL BE ENOUGH WARMING ON MONDAY AFTERNOON TO LIMIT THE
POTENTIAL (EXCEPT ON EXISTING COLD SURFACES)...BUT COOLING MONDAY
NIGHT AND REMAINING INTO TUESDAY WOULD SUPPORT FREEZING RAIN WHERE
THE LIQUID PRECIPITATION OCCURS OVER THE SOUTH CENTRAL. THE SNOW
WILL BE DIMINISH MONDAY MORNING...LIMITING ADDITIONAL
ACCUMULATION...BUT IT STILL LOOKS LIKE SOME LOCATIONS IN SOUTHERN
MENOMINEE COUNTY WILL EXCEED 3 INCHES LATE TONIGHT INTO MONDAY
MORNING. THEN FOR MONDAY NIGHT...EXPECT A DUSTING TO 1.5IN OVER THE
INTERIOR WEST AND CENTRAL.
AS THE SURFACE HIGH NEAR JAMES BAY STRENGTHENS ON TUESDAY
AFTERNOON...EXPECT A HIGH PRESSURE RIDGE TO NOSE BACK SOUTH AND INTO
THE UPPER GREAT LAKES REGION FOR TUESDAY NIGHT INTO WEDNESDAY
EVENING. THIS WILL LEAD TO A DRY PERIOD OVER UPPER MICHIGAN BEFORE
THE NEXT WAVE ARRIVES FOR THE LATER PART OF THE WORK WEEK.
THAT NEXT WAVE IS TIED TO THE UPPER LOW ALONG THE WEST COAST OVER
THE NEXT COUPLE DAYS MOVING THROUGH THE ROCKIES DURING THE MIDDLE OF
THE WEEK AND THEN LIFTING NORTHEAST THROUGH THE GREAT LAKES REGION
THURSDAY-SATURDAY. THIS WILL LEAD TO SEVERAL WAVES OF PRECIPITATION
DURING THAT PERIOD. WON/T GET TOO SPECIFIC IN THE GRIDS DUE TO THE
EVOLVING IDEAS IN THE MODELS...BUT THE FIRST WAVE WILL MOVE THROUGH
ON THURSDAY OUT AHEAD OF THE UPPER LOW. WITH THE WARMING BETWEEN 925-
700MB (PEAKING BETWEEN 1 AND 6C)...WILL SEE THE PRECIPITATION FALL
AS A MIX OR ALL LIQUID. BUT WITH SURFACE TEMPERATURES STILL STAYING
AT OR AROUND FREEZING WITH THE LOW LEVEL EASTERLY FLOW FROM THE
DEPARTING HIGH...WILL CONTINUE TO MENTION A FREEZING RAIN POTENTIAL
FOR THURSDAY MORNING. EXPECT A BRIEF LULL BEHIND THAT FIRST WAVE
BEFORE THE MAIN PRECIPITATION ASSOCIATED WITH THE UPPER LOW LIFTS
NORTHEAST INTO THE GREAT LAKES REGION FOR THE FRIDAY INTO SATURDAY
PERIOD. DIFFERENCES IN THE SPEED OF THE MODELS...AS WELL AS THE
UPPER LOW TRACK...AS IT MOVES THROUGH THE REGION LEADS TO
UNCERTAINTY ON THE PRECIP TYPES. WOULD EXPECT THERE TO BE ENOUGH
WARM AIR TO SUPPORT RAIN FOR MUCH OF FRIDAY (ALTHOUGH THERE COULD BE
SOME FZRA IF IT STARTS EARLY ENOUGH FRIDAY MORNING) BEFORE POSSIBLY
MIXING WITH SNOW FRIDAY NIGHT INTO SATURDAY. THE 00Z GFS CONTINUES
TO BE MUCH FASTER WITH THE LOW MOVING THROUGH AND HAS SHIFTED IT
SIGNIFICANTLY FARTHER TO THE SOUTHEAST...LEADING TO A BETTER
OPPORTUNITY FOR SNOW. LOOKING AT THE 12Z ECMWF ENSEMBLE
MEMBERS...THAT FASTER TREND SEEMS A LITTLE AGGRESSIVE ALTHOUGH THE
SOUTHEAST MOVEMENT IS POSSIBLE WITH SOME ECMWF ENSEMBLE MEMBERS
TRACKING THE LOW THROUGH NORTHERN LOWER MICHIGAN. ALL IN ALL...WITH
THIS PERIOD STILL SEVERAL DAYS OUT...WON/T GET TOO DETAILED AND SHOW
THE GENERAL IDEA FOR POPS AND P-TYPE.
FINALLY...EXPECT TO SEE GRADUALLY WARMING TEMPS THROUGH THE WEEK AS
THE COLD AIR RETREATS TO THE NORTH BUT STILL STAYING AROUND OR BELOW
NORMAL FOR HIGHS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 128 AM EDT SUN APR 5 2015
SFC HIGH PRES WILL DOMINATE AND SHOULD MAINTAIN PREDOMINANT VFR
CONDITIONS AT ALL THE TAF SITES THROUGH THE PERIOD. LOOK FOR AN
INCREASE IN MID- LVL CLOUDS SUN AFTERNOON INTO SUN EVENING AS A WARM
FRONT PUSHES SLOWLY NORTH THROUGH WI.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 345 AM EDT SUN APR 5 2015
WITH THE UPPER GREAT LAKES REGION BETWEEN A HIGH IN SOUTHERN CANADA
AND A WARM FRONT STRETCHING EAST ACROSS THE LOWER GREAT
LAKES...EXPECT PERSISTENT NORTHEAST TO EASTERLY WINDS THROUGH THE
MIDDLE OF THE WORK WEEK. MOST OF THE TIME WINDS WILL STAY BELOW
25KTS...BUT FUNNELING DOWN WESTERN LAKE SUPERIOR COULD LEAD TO GUSTS
UP TO 30KTS LATE MONDAY NIGHT INTO TUESDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...VOSS
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
324 AM EDT SUN APR 5 2015
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE
.SYNOPSIS...
ISSUED AT 324 AM EDT SUN APR 5 2015
LIGHT RAIN AND SNOW WILL SPREAD EAST FROM WISCONSIN EARLY THIS
MORNING. THE SNOW MAY ACCUMULATE AN INCH OR TWO NORTH OF I-96 BEFORE
CHANGING TO RAIN BY LATE MORNING. A FRONTAL BOUNDARY WILL REMAIN
STRETCHED ACROSS LOWER MICHIGAN FOR A FEW DAYS. SEVERAL PERIODS OF
SHOWERS ARE POSSIBLE NEXT WEEK ALONG WITH A FEW THUNDERSTORMS
TUESDAY.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 324 AM EDT SUN APR 5 2015
FORECAST CONCERNS DEAL WITH PCPN TRENDS THROUGH THE PERIOD.
REGIONAL RADAR SHOWS PCPN MOVING EAST FROM WISCONSIN. MUCH OF THIS
PCPN SO FAR IS GOING INTO MOISTENING THE VERY DRY LOWER LEVELS OF
THE ATMOSPHERE. HRRR CONTINUES TO SHOW LIGHT SNOW DEVELOPING OVER
THE NORTHERN HALF OF THE CWA EARLY THIS MORNING. HOWEVER SHORT RANGE
MODELS ARE NOT AS BULLISH ON QPF AND SO WE SCALED BACK ON ACCUMS.
THIS SYSTEM HAS NEVER BEEN A HIGH CONFIDENCE SYSTEM DUE TO IT/S
DEPENDENCE ON MOSTLY FRONTOGENETICAL FORCING FOR PCPN DEVELOPMENT.
WEAK LOW PRESSURE PUSHED A TROUGH SOUTH OVER THE CENTRAL CWA A FEW
HOURS AGO AND THIS BOUNDARY WILL BE THE FOCUS FOR PCPN DEVELOPMENT
OVER THE NEXT FEW DAYS. UPSTREAM RADAR SHOWS 30+ DBZ WESTWARD TO THE
MISSISSIPPI. THUS WE/LL KEEP THE WINTER WEATHER ADVISORY GOING.
SREF/HRRR INDICATE THAT THE PCPN SHOULD WIND DOWN BY LATE MORNING.
LOOKING AT A COUPLE OF INCHES OF SNOW MAINLY NORTH OF A PENTWATER TO
ALMA LINE.
LOW PRESSURE IN THE PLAINS WILL PUSH WARMER AIR NORTHWARD MONDAY AND
TUESDAY WHICH WILL STRENGTHEN THE BAROCLINIC ZONE OVER THE CWA. AS
THE LOW MOVES EAST...RAIN WILL DEVELOP MONDAY NIGHT AND CONTINUE
TUESDAY. MONDAY WILL BE THE WARMER OF THE TWO DAYS WITH HIGHS NEAR
60. BUT THEN THE BOUNDARY WILL SINK SOUTH AND NORTHEAST WINDS WILL
STRENGTHEN PULLING IN COOLER AIR FROM ONTARIO. MODELS INDICATE
ELEVATED INSTABILITY TUESDAY. LI/S NEAR -4C COUPLED WITH MUCAPE
500-1000 J/KG POINT TOWARD SOME THUNDERSTORMS SOUTH OF I-96. TSRA
WAS ADDED TO THE GRIDS TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 324 AM EDT SUN APR 5 2015
THE MAIN CHALLENGE IN THE LONG TERM DEALS WITH THE RISK FOR MIXED
PRECIPITATION TUESDAY NIGHT AND ALSO THE HEAVY RAIN/THUNDER RISK
GOING INTO THE END OF THE WEEK.
MODELS CONTINUE TO SHOW AN ELEVATED WARM LAYER ABOVE A NEAR FREEZING
LOW LEVEL LAYER TUESDAY NIGHT UP AROUND HARRISON AND MOUNT
PLEASANT. BASED ON THIS WILL MAINTAIN THE POSSIBILITY OF ZR MAINLY
NORTH OF A ALMA TO LUDINGTON LINE. TRENDS SEEM TO SUPPORT LESS
SHALLOW COLD AIR. TRIGGERING THE PRECIPITATION WILL BE A WARM FRONT
SITUATED OVER LOWER MI WITH THE NOSE OF A LOW LEVEL JET ACROSS THE
FRONT. WILL NEED TO MONITOR THE THUNDER RISK. HIGHEST POPS MAINLY
OVER SOUTHERN LOWER MI...CLOSER TO THE FRONT AND GULF MOISTURE.
MODELS ARE IN BETTER AGREEMENT IN DRAWING UP GULF MOISTURE THU INTO
THU NIGHT...SENDING THE WARM FRONT NORTH OF GRAND RAPIDS.
INSTABILITY ARRIVES AS WELL. ADDED THUNDER TO THE FORECAST FOR MUCH
OF THE REGION. POPS HAVE BEEN RAISED AS WELL. RAIN COULD BE HEAVY
GIVEN THE LOW LEVEL JET IN PLACE. MODELS VARY ON THE TIMING OF THE
COLD FRONTS ARRIVAL LATER THU NIGHT OR FRI. WILL HOLD OFF ON THE
THUNDER RISK FOR FRI AT THIS TIME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1155 PM EDT SAT APR 4 2015
THE LATEST MODEL DATA SUGGEST THE BAND OF RAIN/SNOW WILL MOSTLY
MISS ALL OF OUR TAF SITES TO THE NORTH. EVEN SO I KEEP THE RAIN
(TO WARM FOR SNOW) IN MKG FOR A FEW HOURS..BETWEEN 09Z AND 12Z AND
I BRING SOME MVFR CONDITIONS IN THERE. LANSING MAY BE TOUCHED BY
THE RAIN AROUND 12Z BUT CONDITIONS SHOULD STAY VFR THERE. ALL AREA
SHOULD SEE SOME CLEARING BY MID AFTERNOON.
&&
.MARINE...
ISSUED AT 324 AM EDT SUN APR 5 2015
A FAIRLY QUIET DAY ON THE LAKE EXPECTED. 5 TO 15 KNOT WINDS WILL
RESULT IN WAVES 2 FEET OR LESS.
&&
.HYDROLOGY...
ISSUED AT 330 PM EDT SAT APR 4 2015
AROUND A QUARTER INCH OF PRECIPITATION IS EXPECTED LATE TONIGHT
THROUGH SUNDAY ACROSS CENTRAL LOWER MICHIGAN...MAINLY IN THE FORM OF
SNOW. A FAIRLY NARROW BAND OF HIGHER QPF AMOUNTS IS POSSIBLE UP TO
AROUND HALF AN INCH. THIS ONE EVENT WILL NOT HAVE A HUGE IMPACT ON
AREA RIVERS...BUT THE PATTERN OVER THE NEXT WEEK IS SHAPING UP TO BE
A WET ONE. THERE WILL BE SEVERAL CHANCES FOR PRECIPITATION OVER THE
NEXT WEEK. RIVER STREAMFLOW PERCENTILE IS CURRENTLY NEAR TO SLIGHTLY
BELOW NORMAL...BUT SOME RIVERS MAY MAKE A RUN AT BANKFULL OVER THE
NEXT WEEK. WPC 7-DAY QPF INDICATES THE KALAMAZOO BASIN AND
HEADWATERS OF THE GRAND COULD SEE IN EXCESS OF AN INCH AND A HALF.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL NOON EDT TODAY FOR MIZ037>040-
043>046-051-052.
LM...NONE.
&&
$$
SYNOPSIS...04
SHORT TERM...04
LONG TERM...MJS
AVIATION...WDM
HYDROLOGY...EBW
MARINE...04
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
133 AM EDT SUN APR 5 2015
.AVIATION...
MID CLOUD WAS QUICKLY DEVELOPING AND STREAMING IN AHEAD OF THE NEXT
SYSTEM. THAT SYSTEM WILL FOCUS ALONG A FRONT THAT HAS SAGGED INTO
CENTRAL LOWER MI. FOR THE DETROIT AREA TAFS...NOT MUCH MORE THAN
THAT MID CLOUD EXPECTED. HOWEVER FOR FNT AND MBS EXPECT CEILINGS TO
FALL 1500 TO 2500 FEET WITH SNOW DROPPING VISIBILITIES TO 1 TO 3
MILES BETWEEN 09Z AND 15Z.
FOR DTW...JUST MID CLOUD EXPECTED FOR THE REMAINDER OF THE NIGHT AND
INTO SUNDAY WITH A LIGHT SOUTHWEST WIND THAT WILL INCREASE TO 12 TO
15 KNOTS DURING THE DAY ON SUNDAY.
//DTW THRESHOLD PROBABILITIES...
* NONE
&&
.PREV DISCUSSION...ISSUED 1026 PM EDT SAT APR 4 2015
UPDATE...
LATEST 00Z AND 01Z UPDATES OF THE NAM/HRRR/RAP HAVE SHIFTED THE
PRECIP BACK NORTHWARD FROM THE 18Z-21Z RUNS...WHICH IS MORE IN
LINE WITH THE CURRENT FORECAST. PRECIPITATION IS STARTING TO BREAK
OUT ACROSS SOUTHERN MN AND FAR NORTHERN IA AND THIS SHOULD RACE
EAST ACROSS THE FRONTAL BOUNDARY THAT WAS POSITIONED ACROSS
CENTRAL LOWER.
ANOTHER TREND WAS THE LOWER QPF WITH ALL OF THE LATEST RUNS SINCE
18Z FROM A THIRD OF AN INCH IN THE MAXIMUM BAND TO MORE LIKE TWO
TENTHS. THIS MAKES A LOT OF SENSE GIVEN ALL OF THE DRY AIR THAT
HAS TO BE OVERCOME FROM THE 00Z SOUNDINGS AT DVN...GRB...APX AND
DTX. ALL OF THOSE SOUNDINGS HAVE PRECIP WATERS IN THE
NEIGHBORHOOD OF .25 INCHES. WITH A LIGHT NORTHEAST WIND ACROSS THE
ADVISORY AREA...SURFACE MOISTURE HAS INCREASED FROM THE LAKE AND
THAT COULD HELP GET THAT INITIAL VIRGA TO START REACHING THE
GROUND A LITTLE QUICKER. STILL WILL MAINTAIN ADVISORY FOR A QUICK
BURST OF 2 INCHES OF SNOW IN A 3 HOUR WINDOW RIGHT AT DAYBREAK.
ALSO WITH THE FRONT STRUGGLING TO GET DOWN TO THE I-69
CORRIDOR...LOOKS LIKE TEMPS AT 925 AND THE SURFACE WILL STRUGGLE
TO SUPPORT ALL SNOW IN THAT I-69 CORRIDOR. WILL INTRODUCE SOME MIX
RAIN AND SNOW THERE.
PREV DISCUSSION...ISSUED 327 PM EDT SAT APR 4 2015
SHORT TERM...REST OF THIS AFTERNOON AND THIS EVENING
RADAR RETURNS EXTENDING FROM NORTHERN LOWER MI INTO THE SAGINAW
VALLEY/THUMB REGION ARE ALONG THE NOSE OF A MID LEVEL THETA E PLUME
AND WITHIN A REGION OF STRONG 280-290K ISENTROPIC ASCENT. WHILE
THERE HAVE BEEN SEVERAL REPORTS OF SNOW ACROSS CENTRAL LOWER
MI...THE LOW LEVEL DRY AIR HAS PROVEN FAIRLY EFFICIENT IN KEEPING
CONDITIONS PRECIP FREE ACROSS MOST OF SE MI. THE INCREASING TRENDS
NOTED ON THE RECENT RADAR/SATELLITE LOOPS DO HOWEVER SUGGEST A
CONTINUED POTENTIAL FOR SOME RAIN/SNOW SHOWERS TO OCCUR PRIOR TO THE
FORCING EXITS TO THE NORTHEAST OF THE THUMB REGION SHORTLY AFTER
21Z. THIS WILL MAINLY BE A CONCERN FOR THE ERN HALF OF THE FORECAST
AREA DURING THE REMAINDER OF THE AFTERNOON. AFTER A PEAK IN WIND
SPEEDS EARLY THIS EVENING...CLEARING SKIES WILL SUPPORT RAPID
DECOUPLING IN THE BOUNDARY LAYER THUS ALLOWING WINDS TO DROP OFF. A
TIGHTENING THERMAL GRADIENT OVERNIGHT ASSOCIATED WITH AN APPROACHING
FRONTAL BOUNDARY AND INCREASING CLOUDS WILL SUPPRESS THE DEGREE OF
COOLING OVERNIGHT...PARTICULARLY ACROSS THE SRN HALF OF THE FORECAST
AREA WHERE MIN TEMPS WILL HOLD IN THE 30S.
LONG TERM... OVERNIGHT THROUGH NEXT SATURDAY
MID/UPPER TROPOSPHERIC HEIGHTS ARE EXPECTED TO RISE OVERNIGHT ACROSS
THE GREAT LAKES REGION AT A FASTER PACE THAN THE LONGWAVE TROUGH
COMPLEX OVER QUEBEC AND NEW ENGLAND TRANSLATES EASTWARD. LOWER
TROPOSPHERIC FLOW WILL INCREASE IN RESPONSE TO THE UNBALANCED
INCREASING HEIGHT GRADIENT ALOFT. THIS POCKET OF MORE ENERGETIC FLOW
WILL IMPINGE INTO THE PRE-EXISTING...BUT RATHER FLAT...THETA-E
GRADIENT IN THE 925-600MB LAYER DRAPED ACROSS CENTRAL LOWER
MICHIGAN.
INCREASING ISENTROPIC ASCENT FORCED BY THE LOW-LEVEL JET RESPONSE
WILL FORCE SATURATION TO COMMENCE WITHIN THE LOOSELY DEFINED FRONTAL
ZONE. THE SATURATION WILL QUICKLY CATALYZE THE THETA-E FIELD INTO A
MUCH BETTER DEFINED STRUCTURE. THE RAPID MASS ADJUSTMENT WILL FORCE
A NARROW...YET ROBUST...AGEOSTROPHIC SECONDARY VERTICAL CIRCULATION
WITHIN THE FRONTAL ZONE.
THE NWP SUITE PRESENTS THIS DEVELOPING FRONTOGENETICALLY FORCED BAND
OF PRECIPITATION WITHIN THE SHARPENING BAROCLINIC ZONE. HOWEVER...
THERE CONTINUES TO BE AN ABNORMALLY LARGE AMOUNT OF SOLUTION
VARIANCE WITH THE PLACEMENT AND EVOLUTION OF THIS FRONTOGENETIC
STRUCTURE.
AVAILABLE ABSOLUTE MOISTURE WILL DICTATE THE PLACEMENT OF THE
INITIAL SATURATION AND ACCOMPANYING STRONG FRONTOGENTIC RESPONSE.
THE REPRESENTATION OF AVAILABLE MOISTURE IS THE SOURCE OF THE NWP
SOLUTION DIVERGENCE. THE 04.12Z NAM IS THE MOST BULLISH...WHICH
TRANSLATES TO A FARTHER SOUTH MUCH MORE AGGRESSIVE DEPICTION.
HOWEVER...THE NAM DEWPOINTS ARE CURRENTLY 8F TOO MOIST IN THE
SURFACE LAYER ACROSS THE MID-MISSISSIPPI VALLEY. THE CMC FAMILY...
GFS...AND LATEST ECMWF ARE A BIT FARTHER NORTH AND LESS AMPLIFIED -
BUT STILL APPEAR TO BE TOO MOIST COMPARED TO RECENT OBSERVATIONS.
THE RAP AND HRRR SEQUENCE HAS BEEN STEADY WITH AN EVEN FARTHER NORTH
DEPICTION AND IS IN BETTER ALIGNMENT WITH THE CURRENT LOW-LEVEL
MOISTURE OBSERVATIONS AND GOES SOUNDER PWAT ESTIMATES. REGARDLESS OF
SOLUTION DEPICTION...SATURATION OCCURS IN THE SUB-FREEZING PORTION
OF BOUNDARY STRUCTURE. THEREFORE...EXPECTING SNOW TO DOMINATE THE
SURFACE OBSERVATIONS. THERE MAY BE SOME RAIN MIXTURE ALONG THE
SOUTHERN FRINGES WHERE LIGHTER PRECIPITATION...REDUCED WET
BULBING...AND PARTIAL SATURATION ALLOW FOR SOME LIQUID DEVELOP.
THE FRONTAL ZONE IS PARALLEL WITH THE MEAN MID-LEVEL FLOW...SO NOT
EXPECTING MUCH LATERAL MOVEMENT WITH THE FRONTAL PRECIPITATION BAND
ONCE IT INITIATES. CONSEQUENTLY...APPRECIABLE ACCUMULATING SNOW
BECOMES A CONCERN. THE REGION OF GREATEST CONFIDENCE FOR MEANINGFUL
ACCUMULATIONS IS ACROSS THE SAGINAW VALLEY AND THUMB REGIONS /WHERE
THE WINTER WEATHER ADVISORY HAS BEEN POSTED/. FARTHER SOUTH...
DURATION OF SNOWFALL WILL BE LIMITED AS THE FRONTAL ZONE CONTRACTS
DUE TO THE LACK OF ABUNDANT MOISTURE. GIVEN THE PRESENTED FORCING IN
THE CONTEXT OF MIXING RATIOS AROUND 2-3 G/KG AND ROUGHLY AN 8 HOUR
DURATION...THE BEST ESTIMATE FOR ACCUMULATIONS IS IN THE 2-3+ INCH
RANGE ACROSS THE ADVISORY.
THE BOUNDARY LAYER WILL MODERATE DURING THE DAY SUNDAY...THUS
CONVERTING THE SNOW TO RAIN FROM SOUTH TO NORTH THROUGH THE LATE
MORNING...AS THE ENTIRE FRONTAL ZONE ALSO SLOWLY MIGRATES NORTH AND
WEAKENS. EXPECTING HIGHS TO RANGE FROM AROUND 60F NEAR THE OHIO
BORDER TO AROUND 40F ACROSS THE SAGINAW VALLEY AND THUMB REGIONS.
THE BOUNDARY WILL LINGER ACROSS CENTRAL LOWER MICHIGAN SUNDAY NIGHT
AND WILL CONTINUE TO BE FOCUS FOR ADDITIONAL SHOWER DEVELOPMENT. SO
WILL HAVE TO MAINTAIN POPS ACROSS THE FAR NORTH.
THE NEXT SYSTEM TO AFFECT THE REGION WILL SURGE IN FROM THE
SOUTHWEST MONDAY NIGHT AND TUESDAY. PLENTY OF GULF MOISTURE
AVAILABLE WITH THIS SYSTEM - PWATS SURGE TO NEAR 1.2 INCHES. THE
COLUMN IN BOTH THE GFS AND ECMWF SOLUTIONS IS WARM ENOUGH TO SUPPORT
ALL RAIN. THE EMERGENCE OF THE STRONGER SYSTEM COLLAPSES THE NEAR
SURFACE FRONT MONDAY NIGHT...ALLOWING SOME COLDER AIR TO FILTER IN
ACROSS THE NORTHERN COUNTIES. THERE IS SOME CONCERN THAT ANY COLDER
SOLUTION WOULD RESULT IN A PERIOD OF ICING MONDAY NIGHT AND TUESDAY
MORNING. CONFIDENCE IS STILL LOW IN THE OVERALL DEPICTION...SO WILL
RESERVE JUDGMENT AT THE MOMENT.
THE EXTENDED FORECAST TUESDAY THROUGH THE END OF NEXT WEEK WILL BE
AN ACTIVE ONE AS A BOUNDARY SETS UP ACROSS THE SOUTHERN GREAT LAKES
REGION. THIS ALLOWS FOR CONTINUAL SHORTWAVES TO RIDE ALONG THE FLOW
BRINGING CHANCES FOR PRECIP TO THE AREA. CURRENTLY...MODELS ARE
ADVERTISING A BREAK IN THE ACTIVITY WEDNESDAY INTO WEDNESDAY NIGHT
AS WEAK UPPER LEVEL RIDGING MOVES IN FOR A SHORT TIME. LATEST
MODELS HAVE COME IN SLIGHTLY WARMER ACROSS THE CWA IN TERMS OF
OVERALL TEMPS...ESPECIALLY ACROSS SOUTHERN PARTS OF THE CWA.
PRECIPITATION TYPE STILL NEEDS TO BE TAKEN IN ACCOUNT BUT
OVERALL... RAIN IS EXPECTED TO BE THE MAIN PTYPE ACROSS MOST OF THE
CWA. SAGINAW VALLEY AND THUMB AREAS WILL SEE THE BETTER CHANCES FOR
MIXED PTYPES.
MARINE...
A BRIEF PERIOD OF GUSTY NORTHWEST WINDS /GUSTS UP TO 25 KNOTS/ ARE
POSSIBLE LATE THIS EVENING AS A COLD FRONT IS DRIVEN SOUTH ACROSS
LAKE HURON. THE FRONT IS FORECAST TO STALL ACROSS LOWER MI ON
SUNDAY...LEAVING A GENERAL WEAK GRADIENT FLOW ACROSS THE GREAT
LAKES. THE FRONT WILL SLOWLY SLIDE SOUTH EARLY NEXT WEEK AS HIGH
PRESSURE STRENGTHENS TO THE NORTH OF THE REGION. THIS WILL ALLOW
NORTHEAST WINDS TO DEVELOP ACROSS LAKE HURON...GRADUALLY
STRENGTHENING TUES INTO WED.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL NOON EDT TODAY FOR MIZ047>049-053>055.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....RBP
UPDATE.......RBP
SHORT TERM...SC
LONG TERM....MANN/SS
MARINE.......MANN
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DULUTH MN
407 PM CDT SUN APR 5 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 406 PM CDT SUN APR 5 2015
MAIN CHALLENGE IN THE SHORT TERM WILL BE THE POTENTIAL FOR A QUICK
HIT OF ACCUMULATING SNOW ACROSS PORTIONS OF THE NORTHLAND TONIGHT.
ADDITIONAL RAIN AND SNOW SHOWERS ARE POSSIBLE MONDAY AFTERNOON.
A WINTER WEATHER ADVISORY IS IN EFFECT FOR AREAS OF EAST CENTRAL
MINNESOTA AND NORTHWEST WISCONSIN FROM MIDNIGHT TONIGHT THROUGH 10
AM MONDAY. AREAS IN THE ADVISORY WILL LIKELY SEE 2 TO 4
INCHES...WITH ISOLATED HIGHER AMOUNTS NOT OUT OF THE QUESTION.
AN AREA OF LOW PRESSURE AT THE SURFACE CONTINUES TO DEVELOP OVER
THE CENTRAL PLAINS THIS AFTERNOON WITH A WARM FRONT EXTENDING TO
THE EAST INTO SRN MN. SOUTH OF THE FRONT THERE IS VERY STRONG WAA
IN THE MID LEVELS...ACROSS A DEEP LAYER...WHICH IS PRODUCING A
STRENGTHENING BAND OF F-GEN JUST SOUTH OF THE TWIN CITIES. AS
EVIDENT ON THE LATEST RUC13 ANALYSIS. CLOUD COVER AND RADAR ECHOES
ARE STARTING TO INTENSIFY WITH THIS AREA OF ENHANCEMENT AND WILL
LIKELY CONTINUE THOUGH THE EVENING. THE COMBINATION OF THIS
RELATIVELY STRONG MESOSCALE FORCING AND BROAD UPPER LEVEL DYNAMICS
IN THE RIGHT ENTRANCE REGION OF THE UPPER JET AND CYCLONIC FLOW
ALOFT WILL PRODUCE THE POTENTIAL FOR RAIN AND SNOW SHOWERS OVER
THE SRN HALF OF THE FORECAST AREA TONIGHT.
THE STRONG LIFT AND SLIGHTLY UNSTABLE ENVIRONMENT ALOFT WILL OCCUR
IN A FAVORABLE REGION OF THE DENDRITIC GROWTH ZONE...WHICH WILL
ALLOW THE PRECIPITATION RATES TO INCREASE LATE THIS EVENING AND
OVERNIGHT. THIS WILL COOL THE COLUMN AND CHANGE ANY RAIN OVER TO
ALL SNOW RELATIVELY QUICKLY. SO...WILL SEE THE POTENTIAL FOR
PERIODIC HEAVY SNOWFALL RATES DURING THIS TIME...WITH A QUICK 2 TO
4 INCHES OVER THE ADVISORY AREA.
A BRIEF BREAK IS POSSIBLE LATE MONDAY MORNING AND EARLY AFTERNOON
BEFORE ANOTHER BATCH OF RAIN AND/OR SNOW DEVELOPS ACROSS THE SRN
COUNTIES AGAIN LATE MONDAY AFTERNOON.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 406 PM CDT SUN APR 5 2015
THE FORECAST AREA WILL BECOME SITUATED BETWEEN VERY DRY CANADIAN
HIGH PRESSURE CENTERED OVER ONTARIO...AND A WARM FRONT WITH
INCREASING WARMTH AND MOISTURE OVER SRN MN THROUGH MUCH OF THE WEEK.
ALTHOUGH LONG RANGE MODELS ARE IN GOOD AGREEMENT THAT A THERMAL
BOUNDARY BECOMES THE FOCUS FOR ONGOING SHOWER CHANCES ACROSS CENTRAL
MINN AND NRN WISCONSIN. AT THIS TIME...THE IRON RANGE AND ARROWHEAD
REGIONS OF NE MINN ARE EXPECTED TO REMAIN DRY THROUGH THE WEEK WITH
THE INFLUENCE OF THE HIGH.
AT THIS TIME...THE BULK OF THE QPF/SNOW ASSOCIATED WITH THE
FRONTOGENESIS MON/MON NIGHT LOOKS TO AFFECT AREAS IN CENTRAL
MINNESOTA...AND NORTHERN WISCONSIN. CARRYING LIKELY POPS FOR
RAIN/SNOW MONDAY NIGHT FROM THE BRAINERD/MILLE LACS AREA...EAST INTO
THE HAYWARD LAKES.
FOCUS TURNS TO LONG WAVE TROUGH THAT DIGS ACROSS THE ROCKIES THROUGH
MID WEEK...DEEPENING INTO A CLOSED LOW IN THE CENTRAL PLAINS BY
THURSDAY. LATEST ECM/GFS/GEM ARE IN REASONABLE AGREEMENT THAT THE LOW
BECOMES CUT OFF AS IT SLOWLY LIFTS ACROSS IA/MN AND INTO THE WESTERN
GREAT LAKES REGION THROUGH FRIDAY. HAVE TRENDED TOWARDS THE SLOWER
ECM SOLUTION FOR POPS AND WINDS. ALTHOUGH VERY FAR OUT IN THE
EXTENDED RANGE...IF THIS LOW CAN MATERIALIZE...GUIDANCE SUGGESTS IT
WILL HAVE THE POTENTIAL TO BRING MUCH NEEDED QPF/RAINFALL OF A HALF
INCH OR MORE TO MUCH OF THE REGION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 106 PM CDT SUN APR 5 2015
VFR CONDITIONS WILL CONTINUE AT ALL SITES UNTIL 00Z. AFTER THIS A
BAND OF RAIN/SNOW MIXTURE WILL DEVELOP. THIS WILL AFFECT
KBRD...KHYR AND KDLH WITH MVFR CEILINGS AND VISIBILITIES. LATEST
MODEL SOUNDINGS SHOW IFR CEILINGS WILL BE POSSIBLE AT TIMES AT
KHYR...BUT KEPT OUT OF THE TAF BECAUSE TIMING IS STILL UNCERTAIN.
WINDS PICK UP TOWARDS THE END OF THE TAF PERIOD FOR KDLH...KBRD
AND KHYR WITH IMPROVING CEILINGS AND VISIBILITIES.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 27 37 26 35 / 30 30 40 40
INL 17 38 22 43 / 0 10 0 10
BRD 28 41 28 39 / 60 50 60 40
HYR 30 40 28 39 / 60 60 70 40
ASX 27 35 27 36 / 40 50 50 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM CDT
MONDAY FOR MNZ034-036-038.
WI...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM CDT
MONDAY FOR WIZ006>009.
LS...NONE.
&&
$$
SHORT TERM...BJT
LONG TERM...GRANING
AVIATION...GRANING/WL
AREA FORECAST DISCUSSION
NWS JACKSON MS
341 PM CDT SUN APR 5 2015
.SHORT TERM...
20Z SURFACE ANALYSIS SHOWS WELL DEFINED WARM FRONT ALONG SE TX AND
S LA COAST. VERY MOIST AND SOMEWHAT UNSTABLE AIR BEING LIFTED
ISENTROPICALLY NORTH OF THIS FRONT IS RESULTING IN WIDESPREAD RAIN
AND EMBEDDED TSRA ACROSS MUCH OF LA AND MS. MOST OF THE CONVECTIVE
ACTIVITY HAS BEEN FOCUSED JUST SOUTH OF OUR AREA...BUT NLDN HAS
SHOWN SOME OCNL STRIKES IN OUR EC LA AND SW MS AREAS. HRRR RUNS
AND GLOBAL MODELS IN GOOD AGREEMENT THAT THIS INITIAL WAVE OF
PRECIPITATION WILL CONTINUE TO HAVE HEAVIEST FOCUS ALONG/S OF
I20...AND WILL SHIFT ESE AND GRADUALLY WEAKEN THROUGH THIS
EVENING. NEW ACTIVITY WILL POTENTIALLY BECOME FOCUSED FARTHER
NORTH INVOF 850 MB FRONT. HAVE ORIENTED WEATHER AND POP GRIDS
BASED ON THESE IDEAS. INCLUDED TSRA IN THE S THIS EVENING AND THEN
ALL AREAS TONIGHT AS ELEVATED INSTABILITY SPREADS NORTH BEHIND 850
MB BOUNDARY.
MONDAY IS A SOMEHWAT INTERESTING DAY. MODELS AGREE THAT ATMOSPHERE
WILL BECOME RATHER UNSTABLE AS LOW LEVEL MOISTURE CONTINUES TO
SURGE NORTH...AND BETTER MID LEVEL LAPSE RATES ARE ADVECTED EAST
WITH WESTERLY MID LEVEL FLOW. WITH 30-40 KT OF MID LEVEL
FLOW...SUFFICIENT SHEAR AND INSTABILITY WILL EXIST FOR ORGANIZED
SEVERE STORMS. MAIN QUESTION WILL BE FORCING FOR CONVECTIVE
INITIATION. HIGH RES AND GLOBAL MODELS HAVE BEEN INSISTENT THAT
CONVECTION WILL DEVELOP THROUGH THE DAY...LIKELY DUE TO A
COMBINATION OF RESIDUAL LOW LEVEL BOUNDARIES...A WEAK MID LEVEL
SHORTWAVE SHOWN BY 20-30M 500 MB HEIGHT FALLS...AND RIGHT ENTRANCE
REGION OF UPPER JET. GIVEN FAVORABLE SHEAR/INSTABILITY...HAVE WENT
AHEAD AND INCLUDED A FEW STRONG/SVR STORMS IN HWO...BUT NOT HIT IT
HARD GIVEN OVERALL WEAK SYNOPTIC FORCING.
AFTER MONDAY EVENING...ANY LOW LEVEL BOUNDARIES SHIFT WELL NORTH
OF THE AREA...AND MID LEVEL RIDGING BECOMES DOMINANT PLAYER IN
WEATHER. EXPECT GENERALLY DRY...BUT WARM AND SEASONABLY
HUMID...CONDITIONS THROUGH MIDWEEK. GENERALLY FOLLOWED MODEL
BLENDS FOR TEMPERATURES THROUGH THE PERIOD. /AEG/
.LONG TERM...
12Z MODEL CONSENSUS CONTINUES TO ADVERTISE A VERY ACTIVE WEATHER
PATTERN FOR LATER PART OF THE WEEK INTO EARLY NEXT WEEK. STILL
DIFFERENCES IN OP MODELS...BUT STRONG SYSTEM STILL EXPECTED TO
LIFT NW OF REGION AND PUSH FRONTAL BOUNDARY WITH ASSOCIATED
CONVECTION LATE THU INTO FRI. 12Z GFS TRENDED WITH A STRONGER PUSH
OF COOLER/DRIER AIR BEHIND THIS SYSTEM FOR WEEKEND BEFORE NEXT BIG
SYSTEM MON. OVERALL TREND OF LOTS OF SUBTROPICAL ENERGY COMING
INTO SW CONUS MAKES US HESITANT TO BUY OFF ON THIS...AND WE USED
MODEL BLEND TO KEEP DECENT POPS INTO WEEKEND. PREVIOUS LONG TERM
DISCUSSION FOLLOWS. /AEG/
MODEL CONSENSUS NOW AGREES THAT A LARGE DISTURBANCE EJECTING INTO
THE PLAINS IN THE SUBTROPICAL JET SHOULD PUSH THE TAIL END OF A
FRONTAL SYSTEM THROUGH THE ARKLATEX AND INTO THE ARKLAMISS DELTA
BETWEEN LATE THURSDAY AND FRIDAY. A LARGE MAJORITY OF THE SYNOPTIC
LIFT WILL BE FOCUSED ACROSS THE MIDWEST BUT THERE SHOULD STILL BE
ENOUGH ASCENT ACROSS AT LEAST NORTHWESTERN ZONES THIS PERIOD TO
TRIGGER SCATTERED THUNDERSTORMS NORTHWEST OF THE NATCHEZ TRACE
CORRIDOR IN AN ENVIRONMENT OF CONSIDERABLE INSTABILITY AND WIND
SHEAR. SHOWER AND THUNDERSTORM CHANCES WILL INCREASE IN ALL AREAS
A GOOD DEAL FRIDAY ALTHOUGH ALONG AND SOUTHEAST OF THE NATCHEZ
TRACE CORRIDOR SEVERE WEATHER INGREDIENTS WILL LIKELY EBB.
CONSIDERING THE ABOVE WE WILL GO AHEAD AND MENTION AN ELEVATED
RISK OF SEVERE THUNDERSTORMS IN NORTHWESTERN ZONES FOR LATE
THURSDAY INTO FRIDAY. CONFIDENCE IN TORNADIC MODES IS NOT YET HIGH
ENOUGH TO FOCUS ON IN THE HWO.
UNFORTUNATELY...MODEL CONSENSUS IS STRONGLY TRENDING TOWARD A
SCENARIO WHERE THUNDERSTORMS LATE THURSDAY INTO FRIDAY COULD BE THE
PROVERBIAL TIP OF THE ICEBERG OF ACTIVE WEATHER GOING THROUGH THE
WEEKEND INTO EARLY NEXT WEEK. INDICATIONS ARE THAT THE BOUNDARY LAID
OUT ACROSS THE REGION LATE FRIDAY BY THE DISTURBANCE PASSING TO THE
NORTH WILL STALL AND TRIGGER MORE STORMS SOMETIME NEXT WEEKEND AS
ANOTHER STRONG DISTURBANCE MOVES THROUGH THE ACTIVE SUBTROPICAL
JET...THIS TIME IN CLOSER PROXIMITY. CONFIDENCE IN DETAILS INTO NEXT
WEEKEND IS TOO LOW TO WARRANT MENTION IN THE HWO YET...BUT AT THIS
JUNCTURE A COMBINATION OF HEAVY RAIN AND SEVERE WEATHER SEEMS QUITE
PLAUSIBLE. /BB/
&&
.AVIATION...
AN AREA OF LIGHT TO MODERATE RAIN WILL CONTINUE TO SPREAD EAST
INTO THE REGION THIS AFTERNOON. VFR FLIGHT STATUSES ARE EXPECTED
TO CONTINUE FOR THE REMAINDER OF THE AFTERNOON...BUT VISIBILITIES
COULD BRIEFLY DROP TO MVFR STATUS IF MODERATE RAIN IS OBSERVED
WITHIN A SITES RESPECTED AERODROME. AS WE GO THROUGH THE EVENING
AND OVERNIGHT HOURS...CEILINGS WILL LOWER...WITH MVFR CONDITIONS
EXPECTED TO PREVAIL AT ALL SITES TOWARD DAY BREAK MONDAY. WINDS
WILL REMAIN FROM THE SOUTHEAST BETWEEN 5-10 KNOTS THROUGH THE REST
OF THE PERIOD. /19/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 58 79 65 83 / 69 52 15 14
MERIDIAN 61 78 63 83 / 52 66 32 13
VICKSBURG 57 81 65 83 / 72 43 12 17
HATTIESBURG 60 81 65 85 / 70 46 14 13
NATCHEZ 59 81 65 83 / 72 48 17 17
GREENVILLE 56 78 65 81 / 44 54 12 17
GREENWOOD 58 78 65 82 / 44 64 17 16
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
AEG/19/BB
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1206 PM CDT SUN APR 5 2015
.UPDATE...
UPDATING TO SPEED UP RAIN TIMING AND LOWER TEMPS...ESPECIALLY
WESTERN AREAS.
&&
.SHORT TERM...
IN SPITE OF VERY DRY AIR LOW LEVEL AIR SAMPLED BY MORNING RAOBS
AND SURFACE OBSERVATIONS...RAIN IS HAVING NO PROBLEM SPREADING
EAST ACROSS NE LA AND INTO FAR WESTERN MS AT MIDDAY. BLENDED PW
PRODUCT SHOWS SURGE OF 1.5 INCH PW INTO EASTERN TX WHICH IS
FEEDING ABOVE DOME OF COOLER AIR...RESULTING IN DEVELOPMENT OF
WIDESRPEAD PRECIPITATION. STILL THINK BASED ON LATEST SHORT TERM
MODEL DATA THAT PRECIPITATION WILL STRUGGLE TO GET INTO NE
SECTIONS THIS AFTERNOON SO HAVE WENT WITH LOWER POPS THERE.
OTHERWISE HAVE INCREASED POPS TO LIKELY/CATEGORICAL MOST AREAS
THIS AFTERNOON IN AGREEMENT WITH LATEST HRRR WHICH SEEMS TO BE
CATCHING UP WITH FASTER PRECIP EVOLUTION. ADDED MENTION OF TSRA IN
SW SECTIONS BASED ON PROXIMITY OF LIGHTNING IN LATEST NLDN
DATA...AND 12Z NAM SOUNDINGS WHICH SHOW INCREASING ELEVATED
INSTABILITY INTO SW SECTIONS THIS AFTERNOON.
USED HRRR TO POPULATE HOURLY TEMPS AS FASTER MOVEMENT OF
PRECIPITATION COMBINED WITH EVAP COOLING MEANS TEMPS WILL NOT WARM
AS MUCH AS EARLIER FORECASTS IN WESTERN HALF OF AREA...AND WILL IN
FACT FALL SOME IN AREAS WEST OF I-55 AS PRECIP MOVES IN. /AEG/
&&
.AVIATION...DESPITE CLOUDS INCREASING FROM WEST TO EAST THROUGH THE
COURSE OF THE AFTERNOON...FLIGHT STATUSES ARE EXPECTED TO REMAIN VFR
THROUGH MUCH OF IT. HOWEVER...AS WE MOVE INTO THIS EVENING AND
OVERNIGHT...CEILINGS SHOULD GRADUALLY LOWER TO MVFR CATEGORIES AS
RAIN SHIFTS FURTHER EAST AND INTO THE REGION. ONCE AGAIN...BOUTS OF
MVFR VISIBILITIES ARE POSSIBLE AT SITES THIS EVENING AND OVERNIGHT
AS A RESULT OF MODERATE RAINFALL BEING OBSERVED ON STATION AS AN
UPPER LEVEL DISTURBANCE SHIFTS EAST THROUGH THE ARKLAMISS...WHILE A
WARM FRONT SLOWLY LIFTS NORTH THROUGH THE REGION. WINDS TODAY AND
TONIGHT WILL BE FROM THE SOUTHEAST BETWEEN 5-10 KNOTS. /19/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 77 59 79 65 / 73 70 64 19
MERIDIAN 78 58 78 63 / 36 63 67 27
VICKSBURG 73 60 81 65 / 81 71 48 14
HATTIESBURG 81 62 81 65 / 56 46 54 12
NATCHEZ 73 62 81 65 / 90 67 33 10
GREENVILLE 72 58 78 65 / 76 77 62 29
GREENWOOD 76 59 78 65 / 71 77 67 30
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
08/19
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
959 AM CDT SUN APR 5 2015
.UPDATE...
NOT PLANNING ANY SIGNIFICANT CHANGES TO THE CURRENT FORECAST.
LARGE AREA OF ISENTROPICALLY DRIVEN RAIN WITH EMBEDDED TSRA
CONTINUES TO BUILD TO OUR W THIS MORNING. RECENT RUNS OF HRRR SEEM
A BIT TOO SLOW/FAR WEST WITH THIS ACTIVITY...BUT GIVEN VERY DRY
AIR AOB 700 MB ON 12Z KJAN RAOB DO THINK IT WILL TAKE SOME TIME
FOR LOWER LEVELS TO SATURATE AND RAIN TO SPREAD EAST. EXPECT
INCREASING/THICKENING MID/HI CLOUDS FROM WEST TO EAST THROUGH THE
AFTERNOON WITH INCREASING RISK OF PRECIPITATION TO REACH GROUND
FROM THE WEST AS WELL. WITH MAINLY HIGHER CLOUDS EXPECT SOME
SUNSHINE...ESPECIALLY EAST...WHICH SHOULD ALLOW TEMPS TO RISE
STEADILY THROUGH THE DAY INTO THE 60S/70S. CURRENT FORECAST SEEMS
TO HAVE THESE TRENDS HANDLED WELL FOR NOW. WILL MONITOR EVOLUTION
OF PRECIPITATION INTO THE AFTERNOON AND ADJUST AS NEEDED...MAY
ALSO NEED TO TWEAK TEMPS DOWN IF THICKER CLOUDS/PCPN ARRIVE A BIT
SOONER THAN CURRENTLY INDICATED. /AEG/
&&
.AVIATION...DESPITE CLOUDS INCREASING FROM WEST TO EAST THROUGH THE
COURSE OF THE AFTERNOON...FLIGHT STATUSES ARE EXPECTED TO REMAIN VFR
THROUGH MUCH OF IT. HOWEVER...AS WE MOVE INTO THIS EVENING AND
OVERNIGHT...CEILINGS SHOULD GRADUALLY LOWER TO MVFR CATEGORIES AS
RAIN SHIFTS FURTHER EAST AND INTO THE REGION. ONCE AGAIN...BOUTS OF
MVFR VISIBILITIES ARE POSSIBLE AT SITES THIS EVENING AND OVERNIGHT
AS A RESULT OF MODERATE RAINFALL BEING OBSERVED ON STATION AS AN
UPPER LEVEL DISTURBANCE SHIFTS EAST THROUGH THE ARKLAMISS...WHILE A
WARM FRONT SLOWLY LIFTS NORTH THROUGH THE REGION. WINDS TODAY AND
TONIGHT WILL BE FROM THE SOUTHEAST BETWEEN 5-10 KNOTS. /19/
&&
.PREV DISCUSSION... /ISSUED 435 AM CDT SUN APR 5 2015/
SHORT TERM...TODAY THROUGH MONDAY NIGHT...EARLY MORNING SURFACE
ANALYSIS HAD A 1028MB HIGH CENTERED OVER THE MID ATLANTIC SEABOARD
AND A 1004MB LOW OVER EASTERN COLORADO. A COOL AND DRY AIRMASS WAS
OVER OUR CWA WITH TEMPERATURES IN THE 40S AND THE 00Z JAN SOUNDING
SHOWED A PW NEAR A QUARTER OF AN INCH. A SOUTHERN STREAM SHORTWAVE
WILL HELP DEEPEN THE SURFACE LOW TODAY WHILE THE SURFACE HIGH SHIFTS
OFF THE EAST COAST. THIS WILL RESULT IN LIGHT RETURN FLOW OVER OUR
CWA TODAY WITH GREATER WAA TO OUR WEST ASSOCIATED WITH THE SURFACE
LOW. IT WILL TAKE ALL MORNING TO MOISTEN OUR AIRMASS BUT HI-RES
MODELS BRING RAIN INTO OUR SOUTHWEST MOST ZONES BY MID AFTERNOON.
UNTIL THEN...MID AND HIGH LEVEL CLOUDS WILL CONTINUE TO THICKEN FROM
THE WEST OVER OUR CWA. DESPITE A RATHER CHILLY START THIS MORNING
TEMPERATURES WILL RECOVER INTO THE LOWER 70S AT MOST SITES WHICH IS
JUST SHY OF NORMAL. BY THIS EVENING A WARM FRONT WILL BE LIFTING
THROUGH THE AREA AND COMBINE WITH A SHORTWAVE TO PRODUCE MORE
NUMEROUS SHOWERS AND A FEW THUNDERSTORMS. BY MID MORNING MONDAY THIS
BOUNDARY WILL BE NORTH OF OUR CWA LEAVING A WARMER AND MUCH MOISTER
AIRMASS OVER OUR CWA. SURFACE DEW POINTS WILL BE BACK IN THE MID 60S
ALONG WITH A PW ABOVE AN INCH AND A HALF. ALTHOUGH THE FOCUS FOR
CONVECTION WILL BE NORTH OF OUR CWA...DAYTIME HEATING WILL LEAD TO
AFTERNOON AND EARLY EVENING CONVECTION. LOCALLY HEAVY DOWNPOURS CAN
BE EXPECTED WITH THE MOST VIGOROUS STORMS. CONVECTION WILL WAIN WITH
THE LOSS OF DAYTIME HEATING MONDAY EVENING. AFTERNOON TEMPERATURES
ARE EXPECTED TO TOP OUT ABOVE NORMAL IN THE UPPER 70S TO LOWER 80S.
THE WARMER THAN NORMAL TEMPERATURES WILL CARRY OVER MONDAY NIGHT
WITH TUESDAY MORNING LOWS IN THE LOW TO MID 60S. NORMAL LOWS RUN
AROUND 50F. /22/
LONG TERM...TUESDAY INTO NEXT WEEKEND...STILL LOOKING TO BE QUITE
WARM AND RATHER HUMID ACROSS THE REGION TUESDAY AND WEDNESDAY AS
MOIST SOUTHERLY LOW LEVEL FLOW OFF THE GULF OF MEXICO CONTINUES AND
THE NORTHERN FRINGE OF SUBTROPICAL RIDGING ALOFT IMPINGES FROM THE
SOUTH. DESPITE THE INHERENT INSTABILITY WHICH WILL BUILD OVER THE
REGION IN THE AFTERNOON EXPECT SHOWERS AND THUNDERSTORM PRODUCTION
TO BE ISOLATED AT BEST THESE DAYS OWING TO LACK OF FORCING AND THE
LIKELIHOOD OF NON-NEGLIGIBLE CONVECTIVE INHIBITION.
MODEL CONSENSUS NOW AGREES THAT A LARGE DISTURBANCE EJECTING INTO
THE PLAINS IN THE SUBTROPICAL JET SHOULD PUSH THE TAIL END OF A
FRONTAL SYSTEM THROUGH THE ARKLATEX AND INTO THE ARKLAMISS DELTA
BETWEEN LATE THURSDAY AND FRIDAY. A LARGE MAJORITY OF THE SYNOPTIC
LIFT WILL BE FOCUSED ACROSS THE MIDWEST BUT THERE SHOULD STILL BE
ENOUGH ASCENT ACROSS AT LEAST NORTHWESTERN ZONES THIS PERIOD TO
TRIGGER SCATTERED THUNDERSTORMS NORTHWEST OF THE NATCHEZ TRACE
CORRIDOR IN AN ENVIRONMENT OF CONSIDERABLE INSTABILITY AND WIND
SHEAR. SHOWER AND THUNDERSTORM CHANCES WILL INCREASE IN ALL AREAS A
GOOD DEAL FRIDAY ALTHOUGH ALONG AND SOUTHEAST OF THE NATCHEZ TRACE
CORRIDOR SEVERE WEATHER INGREDIENTS WILL LIKELY EBB. CONSIDERING THE
ABOVE WE WILL GO AHEAD AND MENTION AN ELEVATED RISK OF SEVERE
THUNDERSTORMS IN NORTHWESTERN ZONES FOR LATE THURSDAY INTO FRIDAY.
CONFIDENCE IN TORNADIC MODES IS NOT YET HIGH ENOUGH TO FOCUS ON
IN THE HWO.
UNFORTUNATELY...MODEL CONSENSUS IS STRONGLY TRENDING TOWARD A
SCENARIO WHERE THUNDERSTORMS LATE THURSDAY INTO FRIDAY COULD BE THE
PROVERBIAL TIP OF THE ICEBERG OF ACTIVE WEATHER GOING THROUGH THE
WEEKEND INTO EARLY NEXT WEEK. INDICATIONS ARE THAT THE BOUNDARY LAID
OUT ACROSS THE REGION LATE FRIDAY BY THE DISTURBANCE PASSING TO THE
NORTH WILL STALL AND TRIGGER MORE STORMS SOMETIME NEXT WEEKEND AS
ANOTHER STRONG DISTURBANCE MOVES THROUGH THE ACTIVE SUBTROPICAL
JET...THIS TIME IN CLOSER PROXIMITY. CONFIDENCE IN DETAILS INTO NEXT
WEEKEND IS TOO LOW TO WARRANT MENTION IN THE HWO YET...BUT AT THIS
JUNCTURE A COMBINATION OF HEAVY RAIN AND SEVERE WEATHER SEEMS QUITE
PLAUSIBLE. /BB/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 73 59 79 65 / 31 70 64 19
MERIDIAN 74 58 78 63 / 10 63 67 27
VICKSBURG 71 60 81 65 / 58 71 48 14
HATTIESBURG 78 62 81 65 / 18 46 54 12
NATCHEZ 72 62 81 65 / 63 67 33 10
GREENVILLE 67 58 78 65 / 52 77 62 29
GREENWOOD 71 59 78 65 / 23 77 67 30
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
08/19
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
933 PM CDT Mon Apr 6 2015
.UPDATE:
Issued at 901 PM CDT Mon Apr 6 2015
Weak, scattered convection just east of 3LF will shift east of the
forecast area later this evening, while another area of scattered,
slightly stronger convection around UUV will move eastward into
portions of southwestern IL later this evening. A persistent and
localized area of fog continues in the FAM area this evening.
Still a lot of uncertainty with regards to additional convection
for late tonight into Tuesday morning. The latest operational
models have most of their QPF across southeast MO and southwest
IL, mainly just southeast of our forecast area. Some of the high
resolution, explicit models develop more organized convection,
potentially an MCS in a region of strong low level warm air
advection on the nose of a southwesterly low level jet which moves
east-southeastward into northeast or central MO towards morning
along and just north of a developing surface warm front. This
convection should be elevated and may produce hail. The 00Z
Tuesday TOP sounding indicated a capped atmosphere which may
hinder much convective development across much of eastern KS and
western MO. For now will continue with the going forecast of pops
increasing into the chance catagory for our entire forecast area
late tonight. Unseasonably warm conditions, about 15 to 20 degrees
above normal can be expected tonight due to low level cloud
cover, south-southeasterly surface winds, low level warm air
advection, and high surface dewpoints. Temperatures in portions of
the forecast area will remain nearly steady through the night.
GKS
&&
.SHORT TERM: (Through Late Tonight)
Issued at 344 PM CDT Mon Apr 6 2015
Low pressure over the Great Plains continues to push a warm and
moist airmass into the region. Guidance suggests that convection
will blossom after 06-08Z somewhere over the CWFA as the nose of a
35-40kt low level jet runs into the 850mb baroclinic zone which is
draped over the area. Resulting isentropic lift should produce an
area of convection late tonight. This is all good in theory,
however short range guidance including the NAM and RAP show a decent
inversion above the level of free convection on forecast soundings
at various locations and times across the area. This puts
significant doubt on timing and coverage of convection late
tonight. Current feeling is that the best chance for storms to
develop will be 08Z or later, and possibly near the I-70 corridor in
Missouri. Ample pre-storm MUCAPE in excess of 1500-2000 J/kg and
persistent LLJ/isentropic lift should allow storms to increase in
coverage through 12Z. Also, with that kind of instability available
and forecast deep layer shear around 40kts, could see some storms
produce large hail. Only the uncertainty of where the storms will
form and ultimate areal coverage has dissuaded me from going with
likely or higher PoPs. As it stands, have 40-50% across the entire
CWFA late tonight, as this should allow the evening shift to
monitor latest trends and adjust as necessary.
Carney
.LONG TERM: (Tuesday through Next Monday)
Issued at 344 PM CDT Mon Apr 6 2015
Main forecast concern continues to be precipitation chances.
Obviously, threat of convection will be very high by Thursday and
Thursday night as deep upper level trof and associated surface
features push into the mid Mississippi Valley...the primary
problem is trying to pin down spatial and temporal convective
trends from tomorrow morning until the widespread and stormy
weather that is expected by Thursday.
The elevated storms that do develop late tonight should wind down
during the morning, leaving unstable but capped AMS blanketing the
area from Tuesday afternoon into Wednesday morning. Current
forecast soundings would suggest that southward sagging frontal
boundary will not be enough to bust through the warm mid level
temps, but there also seems to be some hints of very weak
shortwave energy ejecting into the area from the upper trof to our
west that could produce more elevated activity. In truth I can
probably dream up 2 or 3 scenarios on how convection could evolve
during this time, but with so much uncertainty for now plan on
sticking with going forecast trends, which generally indicate low
chance PoPs over most of the CWA during this time frame.
Fine-tuning will have to wait until this time period gets a bit
closer and specifics (hopefully) become clearer.
In spite of the considerable abiguity in precip trends heading into
mid week, today`s model guidance as well as that over the past
several days continue to point to widespread convection as we head
into Wednesday night and Thursday, with storms continuing into at
least Thursday evening. Intensifying surface low over the central
Plains on Wednesday afternoon will lead to increasing WAA
advection and isentropic ascent north of the frontal boundary.
This low level level forcing should then punch through the mid-
level cap which should begin to weaken by this time as heights
begin to fall in advance of the upper level trof. This round of
convection will work east as the synoptic front pushes north of
the area, placing the entire CWA in the warm sector of the surface
cyclone by Thursday morning. More convection should develop during
the day either from additional shortwave energy or perhaps the
effects of any residual boundaries from Wednesday night`s
activity, with a final shot of convection occurring along the cold
front as we head into the evening hours.
The synoptic models have backed off some on the instability
forecast, perhaps due to extensive cloudiness in the low levels as
well as a weakening of the nearly dry adiabtic lapse rates in the
EML that are progged early on during the forecast cycle. However,
kinematic and synoptic fields still strongly suggest a severe
weather threat...or more likely several episodes of severe
weather...from Wednesday night into Thursday evening. As alluded
to in the day3 and day 4 SPC discussions, threat of large hail and
damaging winds looks fairly substantial, while specific tornado
threat will at least be partially predicated on the specific
locations of fronts and any residual boundaries.
Uncertain how to handle the passage of the cold front/end of
thunderstorm threat. Initial thought was to slow it down a bit as a
common model bias is to be too fast with strong upper level systems,
but on the other hand convection along the front will likely be
screaming to the east, so effective bounday may race ahead of the
actual front. So, will continue thunderstorm threat across the
entire CWA on Thursday night, but will go dry by Friday.
It appears that this dry weather will continue into Saturday, with
thunderstorm chances returning by Sunday and Monday.
In spite of the fact that there will be considerable cloudiness,
there should be plenty of warmth through Thursday, with highs
primarily ranging from the middle 70s to lower 80s. The exception
to this may be over our northern counties on Wednesday, where
southward drift of the cold front will back off temps into the upper
60s and lower 70s. Arrival of the cold air will mean more
seasonable temps by Friday and Saturday.
Truett
&&
.AVIATION: (For the 00z TAFs through 00z Tuesday Evening)
Issued at 709 PM CDT Mon Apr 6 2015
Will continue to see moisture on the increase overnight with
ifr cigs lifting north into TAF sites between 03z-05z Tuesday.
Timing and coverage of thunderstorm development hard to pin down,
so kept vcnty ts mention for late tonight at all locations. Then
as frontal boundary lifts north of forecast area will see cigs
begin to lift and break up a bit by Tuesday afternoon. As for
winds, to remain southeast to south for sites along I-70 corridor
while KUIN will see southeast winds back to the east as front
moves closer, then eventually veer back to the south as front
lifts north of KUIN.
Specifics for KSTL:
Will continue to see moisture on the increase overnight with
ifr cigs lifting north into metro area by 04z Tuesday. Timing and
coverage of thunderstorm development hard to pin down, so kept
vcnty ts mention after 10z Tuesday. Then as frontal boundary
lifts north of forecast area will see cigs begin to lift and break
up a bit by 18z Tuesday afternoon. As for winds, to remain
southeast to south through forecast period.
Byrd
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
709 PM CDT Mon Apr 6 2015
.SHORT TERM: (Through Late Tonight)
Issued at 344 PM CDT Mon Apr 6 2015
Low pressure over the Great Plains continues to push a warm and
moist airmass into the region. Guidance suggests that convection
will blossom after 06-08Z somewhere over the CWFA as the nose of a
35-40kt low level jet runs into the 850mb baroclinic zone which is
draped over the area. Resulting isentropic lift should produce an
area of convection late tonight. This is all good in theory,
however short range guidance including the NAM and RAP show a decent
inversion above the level of free convection on forecast soundings
at various locations and times across the area. This puts
significant doubt on timing and coverage of convection late
tonight. Current feeling is that the best chance for storms to
develop will be 08Z or later, and possibly near the I-70 corridor in
Missouri. Ample pre-storm MUCAPE in excess of 1500-2000 J/kg and
persistent LLJ/isentropic lift should allow storms to increase in
coverage through 12Z. Also, with that kind of instability available
and forecast deep layer shear around 40kts, could see some storms
produce large hail. Only the uncertainty of where the storms will
form and ultimate areal coverage has dissuaded me from going with
likely or higher PoPs. As it stands, have 40-50% across the entire
CWFA late tonight, as this should allow the evening shift to
monitor latest trends and adjust as necessary.
Carney
.LONG TERM: (Tuesday through Next Monday)
Issued at 344 PM CDT Mon Apr 6 2015
Main forecast concern continues to be precipitation chances.
Obviously, threat of convection will be very high by Thursday and
Thursday night as deep upper level trof and associated surface
features push into the mid Mississippi Valley...the primary
problem is trying to pin down spatial and temporal convective
trends from tomorrow morning until the widespread and stormy
weather that is expected by Thursday.
The elevated storms that do develop late tonight should wind down
during the morning, leaving unstable but capped AMS blanketing the
area from Tuesday afternoon into Wednesday morning. Current
forecast soundings would suggest that southward sagging frontal
boundary will not be enough to bust through the warm mid level
temps, but there also seems to be some hints of very weak
shortwave energy ejecting into the area from the upper trof to our
west that could produce more elevated activity. In truth I can
probably dream up 2 or 3 scenarios on how convection could evolve
during this time, but with so much uncertainty for now plan on
sticking with going forecast trends, which generally indicate low
chance PoPs over most of the CWA during this time frame.
Fine-tuning will have to wait until this time period gets a bit
closer and specifics (hopefully) become clearer.
In spite of the considerable abiguity in precip trends heading into
mid week, today`s model guidance as well as that over the past
several days continue to point to widespread convection as we head
into Wednesday night and Thursday, with storms continuing into at
least Thursday evening. Intensifying surface low over the central
Plains on Wednesday afternoon will lead to increasing WAA
advection and isentropic ascent north of the frontal boundary.
This low level level forcing should then punch through the mid-
level cap which should begin to weaken by this time as heights
begin to fall in advance of the upper level trof. This round of
convection will work east as the synoptic front pushes north of
the area, placing the entire CWA in the warm sector of the surface
cyclone by Thursday morning. More convection should develop during
the day either from additional shortwave energy or perhaps the
effects of any residual boundaries from Wednesday night`s
activity, with a final shot of convection occurring along the cold
front as we head into the evening hours.
The synoptic models have backed off some on the instability
forecast, perhaps due to extensive cloudiness in the low levels as
well as a weakening of the nearly dry adiabtic lapse rates in the
EML that are progged early on during the forecast cycle. However,
kinematic and synoptic fields still strongly suggest a severe
weather threat...or more likely several episodes of severe
weather...from Wednesday night into Thursday evening. As alluded
to in the day3 and day 4 SPC discussions, threat of large hail and
damaging winds looks fairly substantial, while specific tornado
threat will at least be partially predicated on the specific
locations of fronts and any residual boundaries.
Uncertain how to handle the passage of the cold front/end of
thunderstorm threat. Initial thought was to slow it down a bit as a
common model bias is to be too fast with strong upper level systems,
but on the other hand convection along the front will likely be
screaming to the east, so effective bounday may race ahead of the
actual front. So, will continue thunderstorm threat across the
entire CWA on Thursday night, but will go dry by Friday.
It appears that this dry weather will continue into Saturday, with
thunderstorm chances returning by Sunday and Monday.
In spite of the fact that there will be considerable cloudiness,
there should be plenty of warmth through Thursday, with highs
primarily ranging from the middle 70s to lower 80s. The exception
to this may be over our northern counties on Wednesday, where
southward drift of the cold front will back off temps into the upper
60s and lower 70s. Arrival of the cold air will mean more
seasonable temps by Friday and Saturday.
Truett
&&
.AVIATION: (For the 00z TAFs through 00z Tuesday Evening)
Issued at 709 PM CDT Mon Apr 6 2015
Will continue to see moisture on the increase overnight with
ifr cigs lifting north into TAF sites between 03z-05z Tuesday.
Timing and coverage of thunderstorm development hard to pin down,
so kept vcnty ts mention for late tonight at all locations. Then
as frontal boundary lifts north of forecast area will see cigs
begin to lift and break up a bit by Tuesday afternoon. As for
winds, to remain southeast to south for sites along I-70 corridor
while KUIN will see southeast winds back to the east as front
moves closer, then eventually veer back to the south as front
lifts north of KUIN.
Specifics for KSTL:
Will continue to see moisture on the increase overnight with
ifr cigs lifting north into metro area by 04z Tuesday. Timing and
coverage of thunderstorm development hard to pin down, so kept
vcnty ts mention after 10z Tuesday. Then as frontal boundary
lifts north of forecast area will see cigs begin to lift and break
up a bit by 18z Tuesday afternoon. As for winds, to remain
southeast to south through forecast period.
Byrd
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
418 PM CDT Sun Apr 5 2015
.SHORT TERM: (Through Late Tonight)
Issued at 414 PM CDT Sun Apr 5 2015
Southerly flow on the western side of the high pressure system over
the eastern seaboard is bringing warmer temperatures and increasing
low level moisture to the area. Even with deep mixing over the area
today, surface dewpoint temperatures are around 5 to 10 degrees
higher than they were yesterday. This moistening trend will
continue tonight and ceilings are expected to lower and thicken.
Warm south flow and abundant cloud cover should make for a warmer
night tonight with temperatures mainly in the mid to upper 40s; and
the more urbanized areas of St. Louis may not drop out of the lower
50s. All of this moisture advection is producing light QPF in the
models. However, it is fairly typical for this QPF to be overdone,
and the high resolution WRF models as well as the HRRR are showing
only very light/low probability precipitation. Have therefore
reduced PoPs to sight chance for most of the night...increasing to
low chance by 12Z over the eastern Ozarks.
Carney
.LONG TERM: (Monday through Next Sunday)
Issued at 414 PM CDT Sun Apr 5 2015
NWP output is maintaining fairly good run to run and model to model
consistency as we head into the new work week. Primary forecast
concern continues to be precipitation chances, with all solutions
maintaining the idea of a strong mid level cap dominating much of
the forecast area into Wednesday.
For Monday the odds of measurable rain still appear to be quite
small, with the rain chances (such as they are) tied to stratified
low level moisture trapped beneath the mid level inversion...which
also makes the odds of any convection quite small over most of the
CWA. In general have kept PoPs in the 15-30% range, and have
There are still indications that the increasing low level jet will
lead to the development of elevated convection on the eastern
fringes of the warmer mid level temps late Monday night and into
Tuesday morning. Forecast soundings from both NAM and GFS indicate
that genesis region for this development may be over
northern/central IL with the activity just clipping our CWA, but QPF
output from the ECMWF certainly suggests development much further to
the southwest...generally along the Mississippi River. For now I`ve
continued with high end chance/low likely PoPs for
northeast/easterns sections of our CWA. Elsewhere during this time
frame time PoPs should remain quite low as strong mid level cap
remains in place, although models do suggest some very weak
shortwaves and mid level moisture working across the area that could
lead to some elevated precip.
Frontal boundary drops south late Tuesday afternoon and Tuesday
night before stalling out from the northern Ozarks into southern IL
on Wednesday morning. Have continued chance PoPs in most areas
during this time, but once again these may be too high if the very
warm mid level temps forecast by the NAM/GFS verify.
Threat of storms should begin to ramp over parts of the CWA on Wednesday.
Not certain how much activity (if any) there will be Wednesday
morning, but all guidance indicates WAA ramping up during the
afternoon as upper level trofs begins to push into the western
Plains. This should set the stage for overrunning convection to
develop over northwest MO during the afternoon as low level ascent
is finally able to overcome the mid level cap. Elsewhere the cap
may still be tough to overcome, but with the boundary in the area
I have continued chance PoPs.
Several rounds of storms are expected from Wednesday night...Thursday...and
into Thursday night...as shortwave energy is ejected into the mid
Mississippi Valley from strong upper level trof pushing into the
Plains. These disturbances will finally erode the mid level
capping, and allow the energy from the increasingly unstable low
level AMS to be released, and have carried likely and higher PoPs
for most of the CWA during this period. Obviously, severe weather
remains a very real concern...especially on Thursday and Thursday
night...due to strength of upper level system, large scale shear,
and expected instability of the early summer airmass.
Passage of the cold front should end the thunderstorm threat over
eastern sections of the CWA on Friday morning, followed by drier and
cooler weather on Saturday. However, medium range models are
suggesting the development of return flow will mean another threat
of showers and storms by Sunday.
Truett
&&
.AVIATION: (For the 18z TAFs through 18z Monday Afternoon)
Issued at 110 PM CDT Sun Apr 5 2015
VFR flight conditions will prevail for the rest of the afternoon
and into the evening across the forecast area. Expect the
southerly flow to continue to bring greater amounts of low level
moisture into the region, and VFR ceilings around 5,000 FT will
develop this evening. Ceilings will eventually lower through the
night into MVFR range, and probably IFR over the eastern Ozarks.
Low ceilings will persist at least through mid to late
morning, but should begin rising during the afternoon. There is
also a chance of some isolated showers or sprinkles
tonight...primarily over the eastern Ozarks.
Specifics for KSTL:
VFR flight conditions will continue at least through the evening,
and probably through most of the night. Expect ceilings around
5,000 FT to overspread the terminal this evening, and ceilings
should lower to MVFR before 12Z. Timing of the lower ceilings is
uncertain, and it is also possible that ceilings could drop below
1,000 FT. IFR seems unlikely at this time though so have kept
ceilings between 1,000-1,900 FT in the TAF. Expect a gradual rise
in ceiling heights through the morning into the afternoon. There
may be an isolated shower or sprinkle overnight into Monday
morning, though probability is too low to mention in the TAF at
this time.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
636 PM CDT MON APR 6 2015
.SHORT TERM...(TONIGHT THROUGH THURSDAY)
ISSUED AT 330 PM CDT MON APR 6 2015
FORECAST CONCERNS CONTINUE TO BE ON AND OFF PRECIPITATION CHANCES
THROUGH THE WEEK...TEMPERATURES...AND SEVERE POTENTIAL.
THE LOW CLOUDS MOVED IN OVERNIGHT...WITH SOME FOG AND DRIZZLE.
THE 12Z OAX SOUNDING WAS SATURATED TO 890MB/2500FT WITH 0.49PWAT.
A FEW STORMS DEVELOPED AROUND BOONE AND ANTELOPE COUNTIES AND
LIFTED TOWARD WAYNE...WITH A STRONGER CLUSTER NEAR WASHINGTON AND
BURT THAT LIFTED NORTHEAST ACROSS HARRISON...MONONA...AND SHELBY
WITH OTHERS IN SOUTHWEST IOWA. THE 12Z H5 MAP SHOWED A WEAK
SHORTWAVE WITH THIS FEATURE IN THE SOUTHWEST FLOW ALOFT. THE H5
CLOSED LOW WAS STILL OFF THE WASHINGTON/OREGON COAST WITH A BROAD
TROF. THERE WAS A WEAK WAVE IN THE FLOW AT H7 APPROACHING THE
LOCAL FORECAST AREA AT 12Z...WITH ANOTHER WEAK WAVE OVER COLORADO
AND YET FARTHER SOUTHWEST OVER SOUTHERN CALIFORNIA. THE H85
PATTERN HAD AN H85 LOW NEAR LBF WITH SOUTHWEST FLOW AHEAD OF IT
AND A POCKET OF 7C DEWPOINTS. THE 10-12DEG. H85 DEWPOINTS WERE
OVER SOUTHERN MO AND ARKANSAS INTO EASTERN OK. THE H7 DEWPOINTS
WERE BETTER OVER TN/AL/MS. THE +20 DEG. C H85 TEMPS WERE OVER TX
WITH THE THERMAL RIDGE NOSING TOWARD OMA AT +12 DEG C.
THE LATEST VISIBLE SATELLITE IMAGERY WAS CLOUDY MOST AREAS...WITH
SOME BUMPY CLOUDS NEAR SD INTO IOWA AND A FEW THINNER SPOTS TOWARD
FAIRBURY... THE SURFACE FRONT WAS NEAR YANKTON TO ONL WITH A
DRYLINE NEAR KGBD KANSAS AND THE WARM FRONT FROM SALINA TO
WICHITA WITH THE CLEARING NEAR THERE. TEMPERATURES WERE IN THE
50S TO LOWER 60S WITH 70S AND 80S SOUTH OF THE WARM FRONT.THE LOCAL
RADAR WAS MAINLY DRY WITH ECHOES TO THE NORTHEAST INTO IOWA.
STILL SOME PATCHY FOG WITH VSBYS 2 TO 4 MILES IN SPOTS.
TONIGHT...SURFACE LOW PRESSURE TRIES TO ORGANIZE A LITTLE FARTHER
SOUTH IN KANSAS WITH NORTHEAST FLOW PREVAILING ACROSS THE FORECAST
AREA. ONE THING TO WATCH WILL BE A 50KT LOW LEVEL JET THAT
INCREASES ACROSS KANSAS INTO MISSOURI. THE 4KM WRF HAS A CLUSTER OF
STORMS DEVELOPING AND MOVING ACROSS NORTHERN KANSAS AND MISSOURI.
THE RAP HAS SHOWERS/TSTORMS IN SOUTHEAST NEBRASKA. IN OUR
FORECAST AREA...ANY PRECIPITATION LOOKS SPOTTY. DO HAVE HIGHER
POPS IN THE SOUTHEAST AND ALSO IN THE NORTHEAST BY MORNING. THE
GFS DOES INCREASE INSTABILITY TOWARD 1000J/KG IN THE SOUTHEAST. ANY
STRONGER STORMS COULD PRODUCE SOME HAIL. THERE MAY BE AN ENHANCED
BAND OF LIGHT PRECIP IN NORTHEAST NEBRASKA BY MORNING NEAR AN
INVERTED TROF AND SOME SHORTWAVE ENERGY PASSES THROUGH.
TUESDAY...THE SURFACE LOW PRESSURE TRACKS NORTHEAST TOWARD SOUTHEAST
NEBRASKA OR NORTHEAST KANSAS...WITH A H85 CIRCULATION OVER THE
FORECAST AREA. THE PRECIPITATION (SHOWERS AND ISOLATED
THUNDERSTORMS) SHOULD MOVE ACROSS THE FORECAST AREA DURING THE
DAY. TEMPERATURES AGAIN SHOULD BE IN THE 50S...WITH 60S CLOSER TO
THE SURFACE LOW FALLS CITY COULD BREAK OUT TO THE LOWER 70S.
TUESDAY NIGHT INTO WEDNESDAY NIGHT AHEAD OF THE STRONGER
SHORTWAVE...FLOW BACKS AND RE-FOCUSES THE LOW LEVEL FLOW WITH
PRECIPITATION CHANCES AGAIN ON THE INCREASE. THE BETTER COVERAGE
SHOULD BE THE SOUTHEAST PART OF THE FORECAST AREA. THE DAY 3 SPC
OUTLOOK HAS THIS AREA ALSO IN THE SLIGHT RISK AND THIS SEEMS
REASONABLE AND WILL BE DEPENDENT ON THE THE SURFACE LOW TRACK. THE
NAM/EC IS NOT QUITE AS FAR NORTH AT THE GFS. SO THIS WILL BE
SOMETHING TO KEEP AN EYE ON.
THE FRONT PUSHES THROUGH THURSDAY WITH THE UPPER LEVEL TROF TO THE
WEST. POST-FRONT SHOWERS WILL CONTINUE INTO THURSDAY WITH
NORTHWEST WINDS.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 330 PM CDT MON APR 6 2015
THE STORM SYSTEM PULLS AWAY THURSDAY NIGHT. THERE IS A SMALL
CHANCE FOR SHOWERS/ISOLATED THUNDERSTORMS FRIDAY NIGHT AND
SATURDAY. ON AND OFF PRECIPITATION CHANCES CONTINUE INTO THE
WEEKEND.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 633 PM CDT MON APR 6 2015
WIDESPREAD IFR CIGS WILL CONTINUE ACROSS ALL OF EASTERN NEBRASKA
OVERNIGHT. VSBYS NEAR 2SM IN DRIZZLE AND FOG ARE LIKELY MUCH OF
THE NIGHT AS WELL. THERE COULD BE A PERIOD BEFORE 04Z WHEN IFR
CIGS SCATTER AT KLNK...BUT EXPECT IFR CIGS TO ROLL BACK IN.
SCATTERED SHOWERS ARE POSSIBLE BETWEEN 12Z AND 18Z...AND AN
ISOLATED THUNDERSTORM COULD DEVELOP DURING THIS TIME AS WELL.
GRADUAL IMPROVEMENT TO VSBYS IS EXPECTED NEAR AND AFTER 18Z WITH
CIGS LIFTING TO NEAR FL010.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...DERGAN
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1158 AM MDT SUN APR 5 2015
.AVIATION...
18Z TAF CYCLE
WIND WILL BE THE MAIN AVIATION HAZARD DURING THE NEXT 24 HRS. WIND
SPEEDS WILL INCREASE AS THE DAY PROGRESSES WITH GUSTY/PULSY WINDS
CONTINUING THROUGH SUNDOWN. ANOTHER ROUND OF STRENGTHENING WIND
EXPECTED MID/LATE MORNING MONDAY. GUSTS TO 35 KT CANT BE RULED OUT
FOR A PERIOD AT LVS/TCC AND GUP. CANT RULE OUT GUSTS TO 30 KT FOR
A BRIEF PERIOD AT AEG/ABQ/SAF/ROW. STRONGER WIND EXPECTED FOR
MONDAY. TODAY AND MONDAY WILL BE HIGH MIXING DAYS THUS LARGER GUST
SPREADS.
50
&&
.PREV DISCUSSION...341 AM MDT SUN APR 5 2015...
.SYNOPSIS...
A WEAK AND RELATIVELY FAST-MOVING DISTURBANCE WILL BRING A FEW SHOWERS
AND POSSIBLY A THUNDERSTORM TO THE AREA THIS EASTER MORNING...WITH THE
BEST OPPORTUNITY EAST OF THE CENTRAL MOUNTAIN. MUCH DRIER AIR WILL
THEN SPREAD EASTWARD IN WAKE OF THE DEPARTING SYSTEM AS THE
AFTERNOON PROGRESSES WITH MODERATE WINDS EXPECTED. TEMPERATURES
WILL REMAIN ABOVE AVERAGE BY SEVERAL DEGREES...INCLUDING MORNING
READINGS THAT WILL GENERALLY BE IN THE 40S AND 50S. A DRY AND
INCREASINGLY WINDY PATTERN WILL THEN DOMINATE THE MONDAY THROUGH
THURSDAY PERIOD...WITH AN ESPECIALLY WINDY AND CRITICAL FIRE
WEATHER PERIOD WEDNESDAY AFTERNOON AND EVENING. TEMPERATURES WILL
REMAIN ABOVE AVERAGE THROUGH WEDNESDAY BEFORE TRENDING COOLER
BEHIND THE NEXT COLD FRONT PUSHES THROUGH THURSDAY.
&&
.DISCUSSION...
LOW AMPLITUDE SHORTWAVE TROUGH EVIDENT IN WATER VAPOR IMAGERY
APPROACHING THE NM/AZ LINE EARLY THIS MORNING. REGIONAL RADAR
MOSAIC SHOWING A FEW WEAK 20 DBZ OR LESS RETURNS VICINITY OF GALLUP
AND THE ZUNI MOUNTAINS...AS WELL AS OVER THE NW AND CENTRAL HIGH
TERRAIN AND SERN-MOST ZONES.
BOUNDARY LAYER CONDITIONS QUITE DRY NEAR/WEST OF THE DIVIDE...BUT
SOME MOISTENING PAST 24 HOURS ALONG THE CENTRAL VALLEY CORRIDOR
WHERE SURFACE DEW POINT TEMPS UP 10 DEGREES OR SO FROM SOCORRO TO
ABQ TO TAOS. LOW LEVEL MOISTENING NOT AS PRONOUNCED ACROSS THE
EAST OWING TO DOWNSLOPING FLOW BUT HIGHER DEW POINT AIR MAY
BRIEFLY ADVECT INTO THE SE ZONES IF SURFACE WINDS CAN STAY A BIT
MORE BACKED AHEAD OF APPROACHING WAVE.
THE LATEST HRRR AND 03Z SREF NOT AS BULLISH ON QPF THIS EASTER
MORNING AS WAS 00Z MODEL SUITE BUT INTERESTINGLY ALL THE MODELS
TO VARYING DEGREES SUPPORT A LINEAR-FORCED QPF BAND FROM THE
MIDDLE RIO GRANDE VALLEY/ABQ AREA EASTWARD ALONG OR JUST NORTH THE
I-40 CORRIDOR WITH ANOTHER FAVORED REGION FROM THE SC MOUNTAINS/HIGHLANDS
NEWD. DID EXPAND MENTION OF ISOLATED SHRA/TSRA FOR CENTRAL/EASTERN
AREAS BUT DECIDED TO AGAINST WIDESPREAD SCATTERED COVERAGE GIVEN
THAT THE WINDOW FOR POTENTIAL PRECIP WILL QUICKLY CLOSE AFTER 15Z.
IMPRESSIVE MID-LEVEL DRY WILL QUICKLY OVERSPREAD THE REGION THIS
AFTERNOON IN WAKE OF THE DEPARTING SHORTWAVE. THIS VERY DRY AIR
MASS WILL THEN DOMINATE THROUGH AT LEAST TUESDAY/TUESDAY NIGHT.
AND IT/S APRIL...SO COINCIDENT WITH THE DRY AIR MASS WILL COME
BREEZY TO WINDY CONDITIONS AREAWIDE AS MID-LEVEL SWLY FLOW STEADILY
INCREASES AHEAD OF THE NEXT UPPER LEVEL STORM SYSTEM.
THE WEDNESDAY-THURSDAY PERIOD LOOKS TO BE THE MOST IMPACTFUL OF THE
UPCOMING WORK WEEK. WARM...DRY AND WINDY PRE-FRONTAL CONDITIONS
EXPECTED ON WEDNESDAY...BEFORE THE TRANSITION TO COOLER POST-
FRONTAL CONDITIONS ON THURSDAY. WEDNESDAY LIKELY THE WINDIEST DAY
FOR MOST AREAS BUT WEDNESDAY NIGHT INTO THURSDAY MORNING COULD BE
EQUALLY AS WINDY ACROSS THE NE QUARTER AS 994MB SURFACE LOW WRAPS
UP AND TRANSLATES NEWD. MAINTAINED LOW POPS ACROSS THE FAR NORTH
DURING THIS MID-WEEK PERIOD. NEXT BACKDOOR COLD FRONT INDICATED
THU NIGHT INTO FRIDAY AM...WITH POTENTIAL FOR SOME LOW CLOUDS/RH
RECOVERY FOR THE EAST. THEN WATCHING ANOTHER LOW LATITUDE SYSTEM
NEXT WEEKEND...BUT LATEST GFS MUCH DRIER FOR OUR AREA TRACKING LOW WELL
TO OUR SOUTH. HOWEVER...PATTERN CERTAINLY TRENDING MORE FAVORABLE FOR
POSSIBLE DRYLINE SCENARIO ACROSS THE EAST. KJ
&&
.FIRE WEATHER...
...A TRANSITION TO A CRITICAL FIRE WEATHER PATTERN STARTING
TODAY...WITH AREAS OF CRITICAL FIRE WEATHER CONDITIONS EXPECTED
THROUGH MID WEEK...
AS A SIGNIFICANT MID LEVEL DRY SLOT APPROACHES NEW MEXICO IN
SOUTHWEST FLOW...WINDY...DRY AND UNSTABLE CONDITIONS ARE EXPECTED TO
PERSIST FOR MUCH OF THE FORECAST PERIOD.
AN UPPER LEVEL LOW CURRENTLY POSITIONED OFF THE PACIFIC NORTHWEST
COAST WILL STEADILY DEEPEN OVER THE WEST COAST AS WEAK RIDGING
REMAINS CENTERED JUST EAST OF NEW MEXICO. A DRY SLOT IS MOVING OVER
SOUTHWEST ARIZONA AS A WEAK UPPER LEVEL DISTURBANCE AHEAD OF THE DRY
SLOT CROSSES NEW MEXICO TODAY. ISOLATED SHOWERS OR THUNDERSTORMS ARE
POSSIBLE EARLY TODAY MAINLY OVER THE EAST WHERE SURFACE MOISTURE IS
GREATEST. LITTLE WETTING PRECIPITATION IS EXPECTED.
THEREAFTER...GUSTY SOUTHWEST WINDS WILL ACT TO STEADILY SCOUR OUT
THE LOW LEVEL MOISTURE AS THE MID LAYER DRY SLOT REACHES NEW MEXICO.
MIXING HEIGHTS REMAIN HIGH ACROSS THE WEST AND INCREASE DRAMATICALLY
ACROSS THE EAST THUS AIDING THE QUICK TRANSITION BACK TO VERY DRY
CONDITIONS. HIGH HAINES VALUES OF 6 WILL DOMINATE WESTERN ZONES. AS
RH FALLS BELOW 15 PERCENT ALL AREAS...REACHING SINGLE DIGIT VALUES
MOST AREAS...CRITICAL FIRE WEATHER CONDITIONS LOOK TO DEVELOP FOR A
FEW HOURS THIS AFTERNOON...MAINLY ALONG AND JUST NORTH OF INTERSTATE
40 EAST OF THE CENTRAL MOUNTAINS...WITH SOME SPOTTY COVERAGE IN THE
WEST WHERE INSTABILITY IS GREATEST. OVERNIGHT RH RECOVERIES WILL BE
POOR.
BY MONDAY...INGREDIENTS LOOK TO BETTER ALIGN FOR CRITICAL FIRE
WEATHER CONDITIONS AND THE WATCH REMAINS IN PLACE. TEMPERATURES WILL
REMAIN 5 TO 15 DEGREES ABOVE NORMAL...DRYING CONTINUES AT THE
SURFACE AND MID LEVELS AND WHILE MIXING IS NOT QUITE AS DEEP
STRONGER GRADIENTS ALOFT AND LEE TROUGHING WILL SUPPORT STRONGER
WINDS. HAINES VALUES WILL EXCEED 5 ALL LOCATIONS AND SINGLE DIGIT RH
VALUES WILL BE IN PLACE FOR SEVERAL HOURS. RH RECOVERIES WILL ONCE
AGAIN BE POOR.
THE UPPER TROUGH APPROACHES NEW MEXICO ON TUESDAY AND CROSSES THE
STATE WEDNESDAY. DESPITE SOME COOLING AND STABILIZATION IN THE
NORTHWEST BY WEDNESDAY...VERY DRY...UNSTABLE AND WINDY CONDITIONS CONTINUE
AS DOES THE THREAT OF CRITICAL CONDITIONS BOTH DAYS.
AS THE BOTH THE UPPER AND SURFACE LOWS MOVE OVER THE GREAT PLAINS ON
THURSDAY...SURFACE WINDS RELAX THOUGH STAY STRONG ENOUGH IN THE EAST
TO POSSIBLY RESULT IN CRITICAL CONDITIONS. A WIND SHIFT LATE
THURSDAY INTO FRIDAY COULD RESULT IN MODEST RH INCREASES MAINLY EAST
AND POSSIBLY THE FIRST DAY OF THE WORK WEEK TO BE FREE OF CRITICAL
CONDITIONS...DESPITE THE PERSISTENCE OF LOW RH VALUES ACROSS THE
WEST. 05
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING FOR
THE FOLLOWING ZONES...NMZ101>109.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
600 AM MDT SUN APR 5 2015
.AVIATION...
12Z TAF CYCLE
VFR CONDITIONS EXPECTED ALL TAF SITES AND MOST LOCATIONS THROUGH
PERIOD. AN AREA OF ISOLATED LIGHT SHOWERS AND PERHAPS A
THUNDERSTORM WILL MOVE FROM CENTRAL LOCALES TO THE EASTERN
PLAINS THIS MORNING...PERHAPS PRODUCING LOCAL SHORT LIVED AREAS OF
MOUNTAIN OBSCURATIONS. THESE SHOWERS WILL DISSIPATE BETWEEN 15Z
AND 17Z. THEREAFTER...GUSTY SOUTHWEST WINDS TO DEVELOP BY MID DAY
AND STEADILY STRENGTHEN DURING THE AFTERNOON HOURS...BEFORE SLOWLY
DIMINISHING AFTER SUNSET.
05
&&
.PREV DISCUSSION...341 AM MDT SUN APR 5 2015...
.SYNOPSIS...
A WEAK AND RELATIVELY FAST-MOVING DISTURBANCE WILL BRING A FEW SHOWERS
AND POSSIBLY A THUNDERSTORM TO THE AREA THIS EASTER MORNING...WITH THE
BEST OPPORTUNITY EAST OF THE CENTRAL MOUNTAIN. MUCH DRIER AIR WILL
THEN SPREAD EASTWARD IN WAKE OF THE DEPARTING SYSTEM AS THE
AFTERNOON PROGRESSES WITH MODERATE WINDS EXPECTED. TEMPERATURES
WILL REMAIN ABOVE AVERAGE BY SEVERAL DEGREES...INCLUDING MORNING
READINGS THAT WILL GENERALLY BE IN THE 40S AND 50S. A DRY AND
INCREASINGLY WINDY PATTERN WILL THEN DOMINATE THE MONDAY THROUGH
THURSDAY PERIOD...WITH AN ESPECIALLY WINDY AND CRITICAL FIRE
WEATHER PERIOD WEDNESDAY AFTERNOON AND EVENING. TEMPERATURES WILL
REMAIN ABOVE AVERAGE THROUGH WEDNESDAY BEFORE TRENDING COOLER
BEHIND THE NEXT COLD FRONT PUSHES THROUGH THURSDAY.
&&
.DISCUSSION...
LOW AMPLITUDE SHORTWAVE TROUGH EVIDENT IN WATER VAPOR IMAGERY
APPROACHING THE NM/AZ LINE EARLY THIS MORNING. REGIONAL RADAR
MOSAIC SHOWING A FEW WEAK 20 DBZ OR LESS RETURNS VICINITY OF GALLUP
AND THE ZUNI MOUNTAINS...AS WELL AS OVER THE NW AND CENTRAL HIGH
TERRAIN AND SERN-MOST ZONES.
BOUNDARY LAYER CONDITIONS QUITE DRY NEAR/WEST OF THE DIVIDE...BUT
SOME MOISTENING PAST 24 HOURS ALONG THE CENTRAL VALLEY CORRIDOR
WHERE SURFACE DEW POINT TEMPS UP 10 DEGREES OR SO FROM SOCORRO TO
ABQ TO TAOS. LOW LEVEL MOISTENING NOT AS PRONOUNCED ACROSS THE
EAST OWING TO DOWNSLOPING FLOW BUT HIGHER DEW POINT AIR MAY
BRIEFLY ADVECT INTO THE SE ZONES IF SURFACE WINDS CAN STAY A BIT
MORE BACKED AHEAD OF APPROACHING WAVE.
THE LATEST HRRR AND 03Z SREF NOT AS BULLISH ON QPF THIS EASTER
MORNING AS WAS 00Z MODEL SUITE BUT INTERESTINGLY ALL THE MODELS
TO VARYING DEGREES SUPPORT A LINEAR-FORCED QPF BAND FROM THE
MIDDLE RIO GRANDE VALLEY/ABQ AREA EASTWARD ALONG OR JUST NORTH THE
I-40 CORRIDOR WITH ANOTHER FAVORED REGION FROM THE SC MOUNTAINS/HIGHLANDS
NEWD. DID EXPAND MENTION OF ISOLATED SHRA/TSRA FOR CENTRAL/EASTERN
AREAS BUT DECIDED TO AGAINST WIDESPREAD SCATTERED COVERAGE GIVEN
THAT THE WINDOW FOR POTENTIAL PRECIP WILL QUICKLY CLOSE AFTER 15Z.
IMPRESSIVE MID-LEVEL DRY WILL QUICKLY OVERSPREAD THE REGION THIS
AFTERNOON IN WAKE OF THE DEPARTING SHORTWAVE. THIS VERY DRY AIR
MASS WILL THEN DOMINATE THROUGH AT LEAST TUESDAY/TUESDAY NIGHT.
AND IT/S APRIL...SO COINCIDENT WITH THE DRY AIR MASS WILL COME
BREEZY TO WINDY CONDITIONS AREAWIDE AS MID-LEVEL SWLY FLOW STEADILY
INCREASES AHEAD OF THE NEXT UPPER LEVEL STORM SYSTEM.
THE WEDNESDAY-THURSDAY PERIOD LOOKS TO BE THE MOST IMPACTFUL OF THE
UPCOMING WORK WEEK. WARM...DRY AND WINDY PRE-FRONTAL CONDITIONS
EXPECTED ON WEDNESDAY...BEFORE THE TRANSITION TO COOLER POST-
FRONTAL CONDITIONS ON THURSDAY. WEDNESDAY LIKELY THE WINDIEST DAY
FOR MOST AREAS BUT WEDNESDAY NIGHT INTO THURSDAY MORNING COULD BE
EQUALLY AS WINDY ACROSS THE NE QUARTER AS 994MB SURFACE LOW WRAPS
UP AND TRANSLATES NEWD. MAINTAINED LOW POPS ACROSS THE FAR NORTH
DURING THIS MID-WEEK PERIOD. NEXT BACKDOOR COLD FRONT INDICATED
THU NIGHT INTO FRIDAY AM...WITH POTENTIAL FOR SOME LOW CLOUDS/RH
RECOVERY FOR THE EAST. THEN WATCHING ANOTHER LOW LATITUDE SYSTEM
NEXT WEEKEND...BUT LATEST GFS MUCH DRIER FOR OUR AREA TRACKING LOW WELL
TO OUR SOUTH. HOWEVER...PATTERN CERTAINLY TRENDING MORE FAVORABLE FOR
POSSIBLE DRYLINE SCENARIO ACROSS THE EAST. KJ
&&
.FIRE WEATHER...
...A TRANSITION TO A CRITICAL FIRE WEATHER PATTERN STARTING
TODAY...WITH AREAS OF CRITICAL FIRE WEATHER CONDITIONS EXPECTED
THROUGH MID WEEK...
AS A SIGNIFICANT MID LEVEL DRY SLOT APPROACHES NEW MEXICO IN
SOUTHWEST FLOW...WINDY...DRY AND UNSTABLE CONDITIONS ARE EXPECTED TO
PERSIST FOR MUCH OF THE FORECAST PERIOD.
AN UPPER LEVEL LOW CURRENTLY POSITIONED OFF THE PACIFIC NORTHWEST
COAST WILL STEADILY DEEPEN OVER THE WEST COAST AS WEAK RIDGING
REMAINS CENTERED JUST EAST OF NEW MEXICO. A DRY SLOT IS MOVING OVER
SOUTHWEST ARIZONA AS A WEAK UPPER LEVEL DISTURBANCE AHEAD OF THE DRY
SLOT CROSSES NEW MEXICO TODAY. ISOLATED SHOWERS OR THUNDERSTORMS ARE
POSSIBLE EARLY TODAY MAINLY OVER THE EAST WHERE SURFACE MOISTURE IS
GREATEST. LITTLE WETTING PRECIPITATION IS EXPECTED.
THEREAFTER...GUSTY SOUTHWEST WINDS WILL ACT TO STEADILY SCOUR OUT
THE LOW LEVEL MOISTURE AS THE MID LAYER DRY SLOT REACHES NEW MEXICO.
MIXING HEIGHTS REMAIN HIGH ACROSS THE WEST AND INCREASE DRAMATICALLY
ACROSS THE EAST THUS AIDING THE QUICK TRANSITION BACK TO VERY DRY
CONDITIONS. HIGH HAINES VALUES OF 6 WILL DOMINATE WESTERN ZONES. AS
RH FALLS BELOW 15 PERCENT ALL AREAS...REACHING SINGLE DIGIT VALUES
MOST AREAS...CRITICAL FIRE WEATHER CONDITIONS LOOK TO DEVELOP FOR A
FEW HOURS THIS AFTERNOON...MAINLY ALONG AND JUST NORTH OF INTERSTATE
40 EAST OF THE CENTRAL MOUNTAINS...WITH SOME SPOTTY COVERAGE IN THE
WEST WHERE INSTABILITY IS GREATEST. OVERNIGHT RH RECOVERIES WILL BE
POOR.
BY MONDAY...INGREDIENTS LOOK TO BETTER ALIGN FOR CRITICAL FIRE
WEATHER CONDITIONS AND THE WATCH REMAINS IN PLACE. TEMPERATURES WILL
REMAIN 5 TO 15 DEGREES ABOVE NORMAL...DRYING CONTINUES AT THE
SURFACE AND MID LEVELS AND WHILE MIXING IS NOT QUITE AS DEEP
STRONGER GRADIENTS ALOFT AND LEE TROUGHING WILL SUPPORT STRONGER
WINDS. HAINES VALUES WILL EXCEED 5 ALL LOCATIONS AND SINGLE DIGIT RH
VALUES WILL BE IN PLACE FOR SEVERAL HOURS. RH RECOVERIES WILL ONCE
AGAIN BE POOR.
THE UPPER TROUGH APPROACHES NEW MEXICO ON TUESDAY AND CROSSES THE
STATE WEDNESDAY. DESPITE SOME COOLING AND STABILIZATION IN THE
NORTHWEST BY WEDNESDAY...VERY DRY...UNSTABLE AND WINDY CONDITIONS CONTINUE
AS DOES THE THREAT OF CRITICAL CONDITIONS BOTH DAYS.
AS THE BOTH THE UPPER AND SURFACE LOWS MOVE OVER THE GREAT PLAINS ON
THURSDAY...SURFACE WINDS RELAX THOUGH STAY STRONG ENOUGH IN THE EAST
TO POSSIBLY RESULT IN CRITICAL CONDITIONS. A WIND SHIFT LATE
THURSDAY INTO FRIDAY COULD RESULT IN MODEST RH INCREASES MAINLY EAST
AND POSSIBLY THE FIRST DAY OF THE WORK WEEK TO BE FREE OF CRITICAL
CONDITIONS...DESPITE THE PERSISTENCE OF LOW RH VALUES ACROSS THE
WEST. 05
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING FOR
THE FOLLOWING ZONES...NMZ101>109.
&&
$$
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
341 AM MDT SUN APR 5 2015
.SYNOPSIS...
A WEAK AND RELATIVELY FAST-MOVING DISTURBANCE WILL BRING A FEW SHOWERS
AND POSSIBLY A THUNDERSTORM TO THE AREA THIS EASTER MORNING...WITH THE
BEST OPPORTUNITY EAST OF THE CENTRAL MOUNTAIN. MUCH DRIER AIR WILL
THEN SPREAD EASTWARD IN WAKE OF THE DEPARTING SYSTEM AS THE
AFTERNOON PROGRESSES WITH MODERATE WINDS EXPECTED. TEMPERATURES
WILL REMAIN ABOVE AVERAGE BY SEVERAL DEGREES...INCLUDING MORNING
READINGS THAT WILL GENERALLY BE IN THE 40S AND 50S. A DRY AND
INCREASINGLY WINDY PATTERN WILL THEN DOMINATE THE MONDAY THROUGH
THURSDAY PERIOD...WITH AN ESPECIALLY WINDY AND CRITICAL FIRE
WEATHER PERIOD WEDNESDAY AFTERNOON AND EVENING. TEMPERATURES WILL
REMAIN ABOVE AVERAGE THROUGH WEDNESDAY BEFORE TRENDING COOLER
BEHIND THE NEXT COLD FRONT PUSHES THROUGH THURSDAY.
&&
.DISCUSSION...
LOW AMPLITUDE SHORTWAVE TROUGH EVIDENT IN WATER VAPOR IMAGERY
APPROACHING THE NM/AZ LINE EARLY THIS MORNING. REGIONAL RADAR
MOSAIC SHOWING A FEW WEAK 20 DBZ OR LESS RETURNS VICINITY OF GALLUP
AND THE ZUNI MOUNTAINS...AS WELL AS OVER THE NW AND CENTRAL HIGH
TERRAIN AND SERN-MOST ZONES.
BOUNDARY LAYER CONDITIONS QUITE DRY NEAR/WEST OF THE DIVIDE...BUT
SOME MOISTENING PAST 24 HOURS ALONG THE CENTRAL VALLEY CORRIDOR
WHERE SURFACE DEW POINT TEMPS UP 10 DEGREES OR SO FROM SOCORRO TO
ABQ TO TAOS. LOW LEVEL MOISTENING NOT AS PRONOUNCED ACROSS THE
EAST OWING TO DOWNSLOPING FLOW BUT HIGHER DEW POINT AIR MAY
BRIEFLY ADVECT INTO THE SE ZONES IF SURFACE WINDS CAN STAY A BIT
MORE BACKED AHEAD OF APPROACHING WAVE.
THE LATEST HRRR AND 03Z SREF NOT AS BULLISH ON QPF THIS EASTER
MORNING AS WAS 00Z MODEL SUITE BUT INTERESTINGLY ALL THE MODELS
TO VARYING DEGREES SUPPORT A LINEAR-FORCED QPF BAND FROM THE
MIDDLE RIO GRANDE VALLEY/ABQ AREA EASTWARD ALONG OR JUST NORTH THE
I-40 CORRIDOR WITH ANOTHER FAVORED REGION FROM THE SC MOUNTAINS/HIGHLANDS
NEWD. DID EXPAND MENTION OF ISOLATED SHRA/TSRA FOR CENTRAL/EASTERN
AREAS BUT DECIDED TO AGAINST WIDESPREAD SCATTERED COVERAGE GIVEN
THAT THE WINDOW FOR POTENTIAL PRECIP WILL QUICKLY CLOSE AFTER 15Z.
IMPRESSIVE MID-LEVEL DRY WILL QUICKLY OVERSPREAD THE REGION THIS
AFTERNOON IN WAKE OF THE DEPARTING SHORTWAVE. THIS VERY DRY AIR
MASS WILL THEN DOMINATE THROUGH AT LEAST TUESDAY/TUESDAY NIGHT.
AND IT/S APRIL...SO COINCIDENT WITH THE DRY AIR MASS WILL COME
BREEZY TO WINDY CONDITIONS AREAWIDE AS MID-LEVEL SWLY FLOW STEADILY
INCREASES AHEAD OF THE NEXT UPPER LEVEL STORM SYSTEM.
THE WEDNESDAY-THURSDAY PERIOD LOOKS TO BE THE MOST IMPACTFUL OF THE
UPCOMING WORK WEEK. WARM...DRY AND WINDY PRE-FRONTAL CONDITIONS
EXPECTED ON WEDNESDAY...BEFORE THE TRANSITION TO COOLER POST-
FRONTAL CONDITIONS ON THURSDAY. WEDNESDAY LIKELY THE WINDIEST DAY
FOR MOST AREAS BUT WEDNESDAY NIGHT INTO THURSDAY MORNING COULD BE
EQUALLY AS WINDY ACROSS THE NE QUARTER AS 994MB SURFACE LOW WRAPS
UP AND TRANSLATES NEWD. MAINTAINED LOW POPS ACROSS THE FAR NORTH
DURING THIS MID-WEEK PERIOD. NEXT BACKDOOR COLD FRONT INDICATED
THU NIGHT INTO FRIDAY AM...WITH POTENTIAL FOR SOME LOW CLOUDS/RH
RECOVERY FOR THE EAST. THEN WATCHING ANOTHER LOW LATITUDE SYSTEM
NEXT WEEKEND...BUT LATEST GFS MUCH DRIER FOR OUR AREA TRACKING LOW WELL
TO OUR SOUTH. HOWEVER...PATTERN CERTAINLY TRENDING MORE FAVORABLE FOR
POSSIBLE DRYLINE SCENARIO ACROSS THE EAST. KJ
&&
.FIRE WEATHER...
...A TRANSITION TO A CRITICAL FIRE WEATHER PATTERN STARTING
TODAY...WITH AREAS OF CRITICAL FIRE WEATHER CONDITIONS EXPECTED
THROUGH MID WEEK...
AS A SIGNIFICANT MID LEVEL DRY SLOT APPROACHES NEW MEXICO IN
SOUTHWEST FLOW...WINDY...DRY AND UNSTABLE CONDITIONS ARE EXPECTED TO
PERSIST FOR MUCH OF THE FORECAST PERIOD.
AN UPPER LEVEL LOW CURRENTLY POSITIONED OFF THE PACIFIC NORTHWEST
COAST WILL STEADILY DEEPEN OVER THE WEST COAST AS WEAK RIDGING
REMAINS CENTERED JUST EAST OF NEW MEXICO. A DRY SLOT IS MOVING OVER
SOUTHWEST ARIZONA AS A WEAK UPPER LEVEL DISTURBANCE AHEAD OF THE DRY
SLOT CROSSES NEW MEXICO TODAY. ISOLATED SHOWERS OR THUNDERSTORMS ARE
POSSIBLE EARLY TODAY MAINLY OVER THE EAST WHERE SURFACE MOISTURE IS
GREATEST. LITTLE WETTING PRECIPITATION IS EXPECTED.
THEREAFTER...GUSTY SOUTHWEST WINDS WILL ACT TO STEADILY SCOUR OUT
THE LOW LEVEL MOISTURE AS THE MID LAYER DRY SLOT REACHES NEW MEXICO.
MIXING HEIGHTS REMAIN HIGH ACROSS THE WEST AND INCREASE DRAMATICALLY
ACROSS THE EAST THUS AIDING THE QUICK TRANSITION BACK TO VERY DRY
CONDITIONS. HIGH HAINES VALUES OF 6 WILL DOMINATE WESTERN ZONES. AS
RH FALLS BELOW 15 PERCENT ALL AREAS...REACHING SINGLE DIGIT VALUES
MOST AREAS...CRITICAL FIRE WEATHER CONDITIONS LOOK TO DEVELOP FOR A
FEW HOURS THIS AFTERNOON...MAINLY ALONG AND JUST NORTH OF INTERSTATE
40 EAST OF THE CENTRAL MOUNTAINS...WITH SOME SPOTTY COVERAGE IN THE
WEST WHERE INSTABILITY IS GREATEST. OVERNIGHT RH RECOVERIES WILL BE
POOR.
BY MONDAY...INGREDIENTS LOOK TO BETTER ALIGN FOR CRITICAL FIRE
WEATHER CONDITIONS AND THE WATCH REMAINS IN PLACE. TEMPERATURES WILL
REMAIN 5 TO 15 DEGREES ABOVE NORMAL...DRYING CONTINUES AT THE
SURFACE AND MID LEVELS AND WHILE MIXING IS NOT QUITE AS DEEP
STRONGER GRADIENTS ALOFT AND LEE TROUGHING WILL SUPPORT STRONGER
WINDS. HAINES VALUES WILL EXCEED 5 ALL LOCATIONS AND SINGLE DIGIT RH
VALUES WILL BE IN PLACE FOR SEVERAL HOURS. RH RECOVERIES WILL ONCE
AGAIN BE POOR.
THE UPPER TROUGH APPROACHES NEW MEXICO ON TUESDAY AND CROSSES THE
STATE WEDNESDAY. DESPITE SOME COOLING AND STABILIZATION IN THE
NORTHWEST BY WEDNESDAY...VERY DRY...UNSTABLE AND WINDY CONDITIONS CONTINUE
AS DOES THE THREAT OF CRITICAL CONDITIONS BOTH DAYS.
AS THE BOTH THE UPPER AND SURFACE LOWS MOVE OVER THE GREAT PLAINS ON
THURSDAY...SURFACE WINDS RELAX THOUGH STAY STRONG ENOUGH IN THE EAST
TO POSSIBLY RESULT IN CRITICAL CONDITIONS. A WIND SHIFT LATE
THURSDAY INTO FRIDAY COULD RESULT IN MODEST RH INCREASES MAINLY EAST
AND POSSIBLY THE FIRST DAY OF THE WORK WEEK TO BE FREE OF CRITICAL
CONDITIONS...DESPITE THE PERSISTENCE OF LOW RH VALUES ACROSS THE
WEST. 05
&&
.AVIATION...
06Z TAF CYCLE
MOST MODELS STILL SHOWING AN AREA OF SHOWERS TRYING TO DEVELOP OVER
CENTRAL NM OVERNIGHT AND MOVING EAST AND EXITING THE STATE SUNDAY
MORNING. CONFIDENCE NOT AS GREAT AS EARLIER BUT WILL CARRY VCSH
AT AEG/ABQ/SAF/LVS. CANT RULE OUT SOME GUSTIER WINDS AS THE SH
PASS. DOUBT CIGS WILL FALL INTO MVFR CATEGORY BUT MAY BE SOME MT
OBSCURATIONS. CLEARING SKIES FROM WEST TO EAST SUNDAY. MODERATELY
STRONG AND GUSTY WINDS WILL IMPACT ALL TERMINALS SUNDAY AFTERNOON
ESPECIALLY ACROSS THE EASTERN PLAINS INCLUDING LVS AND TCC WITH
GUSTS OF 30 TO 35 KT POSSIBLE. 40
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 71 34 70 35 / 0 0 0 0
DULCE........................... 66 26 67 26 / 0 0 0 0
CUBA............................ 67 32 68 33 / 5 0 0 0
GALLUP.......................... 69 28 68 29 / 0 0 0 0
EL MORRO........................ 65 31 64 31 / 0 0 0 0
GRANTS.......................... 69 28 69 28 / 5 0 0 0
QUEMADO......................... 67 35 66 35 / 0 0 0 0
GLENWOOD........................ 75 42 74 41 / 0 0 0 0
CHAMA........................... 60 27 61 28 / 0 0 0 0
LOS ALAMOS...................... 65 40 66 41 / 5 0 0 0
PECOS........................... 67 38 68 39 / 10 0 0 0
CERRO/QUESTA.................... 64 29 65 28 / 5 0 0 0
RED RIVER....................... 56 28 57 29 / 10 0 0 0
ANGEL FIRE...................... 58 24 59 26 / 10 0 0 0
TAOS............................ 65 29 66 29 / 5 0 0 0
MORA............................ 67 33 67 35 / 10 0 0 0
ESPANOLA........................ 72 38 72 39 / 5 0 0 0
SANTA FE........................ 66 40 66 40 / 10 0 0 0
SANTA FE AIRPORT................ 71 35 71 35 / 10 0 0 0
ALBUQUERQUE FOOTHILLS........... 73 45 73 45 / 5 0 0 0
ALBUQUERQUE HEIGHTS............. 76 45 76 44 / 5 0 0 0
ALBUQUERQUE VALLEY.............. 77 39 76 41 / 5 0 0 0
ALBUQUERQUE WEST MESA........... 77 41 76 43 / 5 0 0 0
LOS LUNAS....................... 79 38 79 38 / 5 0 0 0
RIO RANCHO...................... 76 42 76 44 / 5 0 0 0
SOCORRO......................... 81 45 81 42 / 5 0 0 0
SANDIA PARK/CEDAR CREST......... 69 40 69 40 / 10 0 0 0
TIJERAS......................... 72 40 72 41 / 10 0 0 0
MORIARTY/ESTANCIA............... 70 34 70 35 / 10 0 0 0
CLINES CORNERS.................. 70 37 70 37 / 10 0 0 0
GRAN QUIVIRA.................... 71 41 70 40 / 10 0 0 0
CARRIZOZO....................... 77 43 76 43 / 10 0 0 0
RUIDOSO......................... 72 39 71 40 / 20 0 0 0
CAPULIN......................... 70 39 70 39 / 10 0 0 0
RATON........................... 73 33 74 34 / 10 0 0 0
SPRINGER........................ 73 35 74 35 / 10 0 0 0
LAS VEGAS....................... 70 36 70 36 / 10 0 0 0
CLAYTON......................... 78 47 82 47 / 10 0 0 0
ROY............................. 75 39 76 39 / 10 0 0 0
CONCHAS......................... 80 46 80 45 / 10 0 0 0
SANTA ROSA...................... 78 43 78 43 / 20 0 0 0
TUCUMCARI....................... 82 45 85 45 / 10 0 0 0
CLOVIS.......................... 80 46 82 47 / 20 0 0 0
PORTALES........................ 81 47 83 46 / 20 0 0 0
FORT SUMNER..................... 81 46 82 45 / 20 0 0 0
ROSWELL......................... 84 47 86 46 / 10 0 0 0
PICACHO......................... 78 46 77 44 / 10 0 0 0
ELK............................. 73 45 72 45 / 10 0 0 0
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING FOR
THE FOLLOWING ZONES...NMZ101>109.
&&
$$
41
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
947 PM EDT MON APR 6 2015
.SYNOPSIS...
A SLOW MOVING FRONTAL SYSTEM WILL KEEP THE WEATHER UNSETTLED FOR
MUCH OF THE UPCOMING WEEK.
&&
.NEAR TERM /THROUGH TUESDAY/...
945 PM UPDATE...
MAIN CHANGE THIS FORECAST RUN WAS TO PULL WAY BACK ON THE POPS
DURING THE SECOND HALF OF THE OVERNIGHT AND INTO TUESDAY MORNING.
MAIN WAVE OF PRECIP IS MOVING THROUGH THE FA ATTM AND IS PROGGED
TO WEAKEN AND DIMINISH AFTER MIDNIGHT. HRRR SEEMS TO HAVE A GOOD
HANDLE ON THE CURRENT TRENDS.
WE ARE SLOWLY INGESTING NEW MODEL/MOS DATA AFTER THE AWIPS II
INSTALL EARLIER, SO WE ARE A LITTLE LIMITED THIS EVENING ON WHAT
DATA WE CAN UTILIZE TO BLEND WITH.
1 PM UPDATE...
CLOUDS ARE BEGINNING TO ENCROACH FROM THE WEST ASSOCIATED WITH A
SERIES OF SHORTWAVES THAT ARE BEGINNING TO EJECT AND RACE EAST
OUT OF THE LARGE SCALE TROUGH OVER THE WESTERN US. THE FIRST
SHOWERS REACHING THE GROUND CAN BE SEEN OVER NORTHERN OHIO...AND
GUIDANCE SHOWS THE MOISTURE CONTINUING TO SURGE INTO THE REGION ON
A STRONG LOW LEVEL SWLY FLOW. GEFS/SREF SHOW PWATS RISING TO 1-2
ST DEV ABOVE NORMAL...CONTINUING INTO AT LEAST TUESDAY.
SREF SHOWS INCREASING CHANCES FOR RAIN EARLY TONIGHT...WITH
LIKELY TO CATEGORICAL POPS DEVELOPING BETWEEN 21-03Z. GEFS IS A
LITTLE LESS AGGRESSIVE BUT STILL SUGGESTS MOST IF NOT ALL
LOCATIONS WILL SEE MEASURABLE RAINS OVERNIGHT. OPERATIONAL RUNS
OF THE GFS/NAM ARE A LITTLE MORE DETAILED...HINTING AT SOME SORT
OF WAVE FORMING ALONG THE SLOW MOVING WARM FRONT AND BRINGING THE
INITIAL SURGE OF SHOWERS...WITH SOMEWHAT OF A LULL POSSIBLE FOR
THE SECOND HALF OF THE OVERNIGHT...ESPECIALLY OVER NORTHERN
AREAS.
LOWS WILL RANGE FROM THE CHILLY MID 30S OVER THE NORTH TO AROUND
50 IN THE FAR SOUTH.
&&
.SHORT TERM /TUESDAY NIGHT/...
1 PM UPDATE...
COLD HIGH PRESSURE ANCHORED TO OUR NORTH AND THE WAVY BOUNDARY
TO OUR SOUTH WILL BE THE WEATHER DRIVERS FOR THE SHORT TERM. THE
GFS SUPPRESSES MOST OF THE PRECIP SOUTH TO AROUND THE NY/PA
BORDER BY LATER TUESDAY NIGHT EARLY WED AM...WHILE THE OPERATIONAL
NAM AND ECMWF SHOW LIGHT QPF BEING MORE GENEROUSLY SPREAD ABOUT
THE REGION.
THE GEFS IS A LITTLE LESS OPTIMISTIC THAN ITS OPERATIONAL
COUNTERPART WHILE THE SREF SUGGESTS THE NAM MAY BE TOO DRY. WILL
USE A BLEND OF POPS FOR THE PERIOD WHICH LENDS SMALL CONFIDENCE TO
ACTUALLY TRYING TO TIME WHEN THE BEST CHANCES FOR RAIN OR NO RAIN
WILL END UP BEING.
LOCAL RIVERS AND STREAMS ARE RUNNING HIGH...SO RAINFALL AMOUNTS
NEED TO BE MONITORED FOR POSSIBLE PROBLEMS. AT THIS POINT...NO
FLOODING IS EXPECTED.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
UPDATED 300 PM...BLENDED PREVIOUS FORECAST WITH THE LATEST MEDIUM
RANGE/WPC GUIDANCE WHICH RESULTED IN MINOR CHANGES. KEPT RISK FOR
FREEZING RAIN AROUND MID-WEEK WITH HIGHEST POPS ON DAY 5/FRI WITH
A SHARP COLD FRONTAL PASSAGE. OVERALL AN ACTIVE AND WET PERIOD
THROUGH THE END OF THE WEEK BEFORE THINGS DRY OUT BEHIND THE FRONT
THIS WEEKEND.
PREVIOUS DISCUSSION...
FORECAST ADJUSTED FOR TRENDS AND LATEST WPC
GUIDANCE. A COUPLE THINGS TO NOTE. ONE IS THAT STRONG HIGH
PRESSURE WILL BECOME CENTERED OVER FAR NORTHERN NEW ENGLAND-LOWER
ST. LAWRENCE SEAWAY LATE WEDNESDAY NIGHT INTO EARLY
THURSDAY...WHICH IS A GOOD SET UP FOR COLD AIR DAMMING. THERE
APPEARS TO BE SOME POTENTIAL FOR LIGHT FREEZING RAIN HIGHER
ELEVATIONS OF THE NORTHEASTERN ZONES DURING THAT TIME...THOUGH
PRECIP CHANCES ITSELF NOT THAT HIGH AND AMOUNTS IF ANY WOULD BE
VERY LIGHT. OTHERWISE THURSDAY- FRIDAY PERIOD LOOKS WET WITH MOIST
WARM AIR ADVECTION ALLOWING TEMPERATURES TO TREND ABOVE
CLIMATOLOGY INTO THE WEEKEND. OTHER THING THAT LATEST OPERATIONAL
GFS-ECMWF RUNS INCREASE CONFIDENCE IN LARGE SURFACE HIGH
DOMINATING SECOND HALF OF THE WEEKEND...FOR DRY AND MILD
CONDITIONS SUNDAY.
PREVIOUS DISCUSSION...
CLOSELY FOLLOWED WPC GUIDANCE. A WET PATTERN CONTINUES AS BROAD SW
FLOW ALOFT PREVAILS THROUGHOUT THE EXTENDED FORECAST PERIOD. THIS
PATTERN ALOFT ALLOWS FOR MULTIPLE SHORTWAVES WITHIN THE UPPER LVL
FLOW TO PASS OVER THE REGION BRINGING A CHANCE FOR RAIN SHOWERS
EACH DAY. ATTM... THE BEST CHANCE FOR RAIN SHOWERS OVER THE REGION
WILL BE THURS NIGHT THRU FRIDAY NIGHT. AS WE ARE AT THE TAIL END
OF WINTER... THERE IS STILL A CHANCE AT NIGHT THAT SOME OF THESE
SHOWERS COULD TRANSITION OVER TO SNOW. NO MAJOR ACCUMULATIONS ARE
EXPECTED THROUGH THE EXTENDED. TEMPERATURES DURING THIS TIME FRAME
ARE EXPECTED TO BE AT OR ABOVE THE SEASONAL NORM.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
VFR SHRA FROM A MID CLOUD LAYER WILL ADVECT NORTHEAST ACROSS ALL
TAFS SITES IN THE NEAR TERM THRU 6Z. I HAVE VFR SHRA UNTIL ARND
8-9Z MOST TAF SITES. THEN THE SHOWERS WILL WEAKEN UNTIL ANOTHER
WAVE BRINGS A MORE WIDESPREAD AREA OF RAINFALL TUE PM TO MUCH OF
PA. AT THIS POINT THERE IS UNCERTAINTY AS TO HOW EXTENSIVE AND HOW
FAR NORTH THIS RAIN SHIELD MAKES IT. BEST CHANCE FOR CONTINUED
RAINFALL WILL BE AT KAVP SO KEPT SHRA GOING THRU 00Z WED WITH A
CIG OF 3500 FEET BY TUE PM. IF THE RAIN COMES IN STEADIER AND
FARTHER NORTH I CUD SEE IFR CONDITIONS AT LEAST...POSSIBLY NORTH
TO THE SRN TIER OF NY AND OF COURSE ALL OF NE PA TUE PM. LATER
SHIFTS WILL HAVE TO WATCH OUT FOR THIS. FOR NOW GIVEN THAT IT IS
SO FAR OUT IN THE TAF PERIOD AND THERE IS MODEL UNCERTAINITY KEPT
SHRA FARTHER S MORE IN LINE WITH THE LATEST 18Z NAM MODEL.
.OUTLOOK...
TUE NGT-FRI...BUSY PATTERN WITH A SLOW MOVING FRONTAL SYSTEM
REMAINING IN THE VICINITY...ALONG WITH FREQUENT PERIODS OF
MVFR/IFR ALONG WITH SHOWERS...MAINLY OF RAIN.
SAT- VFR IN ISLD SHRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...DJP
SHORT TERM...
LONG TERM...
AVIATION...DJN
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
739 PM EDT MON APR 6 2015
.SYNOPSIS...
A FRONTAL SYSTEM OVER THE NORTH COUNTRY EARLY TONIGHT WILL MOVE
SOUTH OF THE REGION BY TUESDAY AS A RIDGE OF HIGH PRESSURE BUILDS
SOUTH FROM CANADA. THIS HIGH PRESSURE AREA WILL BE OVER THE NORTH
COUNTRY TUESDAY NIGHT THROUGH MIDDAY ON WEDNESDAY BEFORE ANOTHER
SURGE OF MOISTURE MOVE NORTHEAST FROM THE OHIO VALLEY WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT BRINGING MORE RAIN AND SNOW SHOWERS
TO THE REGION.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 733 PM EDT MONDAY...FRONTAL BOUNDARY THAT WAS MOVING NORTH
THROUGH THE DAY TODAY HAS STALLED THIS EVENING AND WILL BEGIN A
TREK BACK SOUTHWARD OVERNIGHT AND ON TUESDAY. BAND OF LIGHT SNOW
OVER THE NORTHERN TIER OF COUNTIES WILL REMAIN STALLED OVER THE
AREA AND GRADUALLY DIMINISH THROUGH THE REMAINDER OF THE EVENING
AND INTO THE FIRST PART OF THE OVERNIGHT. SOME AREAS HAVE SEEN A
LIGHT ACCUMULATION OF SNOWFALL...AND A DUSTING-2" TOTAL LOOKS GOOD
ACROSS THE NORTHERN TIER AND NORTH CENTRAL/NORTHEAST VERMONT.
ADDITIONAL AREAS OF LIGHT PRECIPITATION APPEAR TO BE ORGANIZING
OVER PARTS OF CENTRAL NEW YORK AND MAY SPREAD INTO SOUTHERN
VERMONT LATER THIS EVENING. CONDITIONS SHOULD BEGIN TO DRY OUT
HEADING INTO THE EARLY MORNING HOURS. LOW TEMPERATURES GENERALLY
UPPER 20S TO MID 30S.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 404 PM EDT MONDAY...A RIDGE OF HIGH PRESSURE WILL BUILD
SOUTH FROM CANADA ON TUESDAY. HAVE GONE WITH JUST SLIGHT CHANCE
POPS FOR RAIN OR SNOW SHOWERS TUESDAY MORNING...AND THEN EXPECTING
THE REMAINDER OF THE DAY TO REMAINDER OF THE DAY TO BE DRY. THIS
RIDGE OF HIGH PRESSURE WILL THEN REMAIN OVER THE NORTH COUNTRY
TUESDAY NIGHT AND THROUGH MIDDAY ON WEDNESDAY. ANOTHER SURGE OF
MOISTURE WILL WILL MOVE NORTHEAST FROM THE OHIO VALLEY WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT WITH MORE OVERRUNNING RAIN AND SNOW
SHOWERS. MODEL ALSO SHOWING AN INVERTED TROUGH WILL SET UP ACROSS
THE SAINT LAWRENCE VALLEY BY LATE WEDNESDAY AFTERNOON INTO
WEDNESDAY NIGHT. HAVE GONE WARMER THAN THE GFS MOS GUIDANCE FOR
MIN TEMPERATURES TUESDAY NIGHT AND WEDNESDAY NIGHT...AS THIS
GUIDANCE LOOKS TOO COOL...ESPECIALLY GIVEN CLOUD COVER OVER THE
REGION.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 336 PM EDT MONDAY...12Z GLOBAL SUITE OF GUIDANCE IS IN GOOD
AGREEMENT ON THE EXPECTED PATTERN. FOR MUCH OF THE PERIOD, LARGE-
SCALE MID-/UPPER-LEVEL HEIGHT FALLS REBUILD INTO THE INTERMOUNTAIN
WEST, WHICH LEADS TO DOWNSTREAM UPPER RIDGING ACROSS THE EASTERN
THIRD OF THE COUNTRY. IT APPEARS THAT A PATTERN CHANGE TOWARD
MILDER WEATHER IS IN THE OFFING. IT`S MORE REPRESENTATIVE OF
SPRING THAN WHAT WE`VE EXPERIENCED RECENTLY, AT LEAST.
THURSDAY: LOW-LEVEL WARM ADVECTION/ISENTROPIC ASCENT REGIME WITH
WARMING 1000-500 MB THICKNESSES PRODUCES MAINLY LIGHT RAIN. THE ONE
EXCEPTION WILL BE ACROSS EASTERN VT IN THE MORNING, AS COLD-AIR
DAMMING SIGNATURE EVIDENT IN SEA-LEVEL PRESSURE AND THICKNESS FILEDS
SUGGEST NEAR TO SUB-FREEZING LOW-LEVELS IN THESE AREAS. STRENGTH OF
WARM ADVECTION SHOULD READILY OVERCOME THIS LAYER, THOUGH, SO PERIOD
OF FROZEN PRECIP IS BRIEF. HIGHS LOWER 40S EASTERN VT TO AROUND 50
FOR ST. LAWRENCE VALLEY.
THURSDAY NIGHT: BEST SURGE OF WARM FRONTAL PRECIP COMES IN DURING
THE EARLY PART OF THURSDAY NIGHT. SOUTH WINDS ALSO ON THE
INCREASE, SO WHILE POPS ARE GENERALLY IN THE LIKELY CATEGORY, I DO
SHOW A RELATIVE MIN IN POPS IN THE CHAMPLAIN VALLEY, AS BREEZY SOUTH
WINDS TEND TO LIMIT QPF LOCALLY. ASIDE FROM EASTERN VT WHERE MID
30S ARE FORECAST, LOWS OTHERWISE ARE UPPER 30S TO THE MID 40S
GIVEN ABUNDANCE OF CLOUDS/PRECIP.
FRIDAY: 500 MB RIDGE CONTINUES TO AMPLIFY AHEAD OF A DIGGING
SHORTWAVE INTO THE NORTHERN/CENTRAL PLAINS. WITH MUCH OF THE NORTH
COUNTRY IN A WARM SECTOR BETWEEN APPROACHING OCCLUDED FRONT, WARM
THERMAL AND MOISTURE ADVECTION SHOULD BE UNDERWAY ON FRIDAY. IN
FACT, PWAT VALUES DO CLIMB OVER AN INCH PER THE 12Z GFS. SHOULD SEE
PERIODS OF LIGHT SHOWERS IN THE WARM SECTOR, WITH THE GREATEST POPS
TIED MOSTLY TO THE COLD FRONT. 925/850 MB TEMPS WARM TO AROUND +10C,
THOUGH LIKELY PARTIAL TO MOSTLY CLOUDY SKIES ONLY YIELD HIGHS IN THE
MID TO UPPER 50S. RESULTING SNOW MELT SHOULD PRODUCE SOME RISE IN
RIVER LEVELS, THOUGH CURRENT STAGES STILL ARE PRETTY LOW.
FRIDAY NIGHT: OCCLUDED FRONTAL BOUNDARY MOVES THROUGH THE NORTH
COUNTRY FRIDAY NIGHT. RAIN SHOULD BE FOCUSED MORE ALONG THE FRONT.
SOME QUESTION AS TO HOW MUCH QPF FALLS WITH THE FRONT AND PENDING
HOW MUCH SNOW CAN MELT, COULD HAVE TO KEEP AN EYE ON OUR RIVERS
FOR RISES. THOUGH TEMPERATURES ALOFT COOL BEHIND THE FRONT, RH
PROFILES SUGGEST AT LEAST PARTIAL CLOUDINESS, WHICH KEEPS LOWS
STILL IN THE 30S/AROUND 40.
SATURDAY: SECONDARY COLD FRONT SWEEPS ACROSS THE NORTH COUNTRY
DURING THE DAY SATURDAY. I`VE SHOWN CHANCE POPS ACROSS NORTHERN
ZONES FOR SATURDAY, WITH HIGHS IN THE UPPER 40S/AROUND 50.
SATURDAY NIGHT - SUNDAY: GENERALLY DRY AS HIGH PRESSURE BUILDS IN,
BUT COLD ADVECTION REGIME BRINGS 850 MB TEMPS BACK DOWN TO -4 TO -
6C. CONTINUED DRY WEATHER INTO SUNDAY UNDER SURFACE HIGH PRESSURE.
USED SUPERBLEND GUIDANCE FOR TEMPS THIS PERIOD, WITH LOWS IN THE
UPPER 20S/LOWER 30S SATURDAY NIGHT AND HIGHS UPPER 40S TO MID 50S.
PATTERN THEN GETS A BIT LESS CERTAIN SUNDAY NIGHT INTO MONDAY, BUT
INDICATIONS ARE FOR A RETURN TO MILDER WEATHER FOR EARLY NEXT
WEEK. LARGELY STUCK WITH BLENDED GUIDANCE TO CLOSE THE EXTENDED.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
THROUGH 18Z TUESDAY...A MIX OF FLIGHT CATEGORIES BETWEEN VFR TO
IFR AS WARM FRONT LIFTS TO ABOUT THE CANADIAN BORDER, AND SAGS
BACK SOUTHWARD LATER THIS EVENING. PRETTY BUSY TAF PERIOD WITH LOW
VISIBILITIES AND MOUNTAINS OBSCURED BY LOW CEILINGS, BUT OVERALL
LIMITED IMPACT TO AVIATION GROUND OPERATIONS.
COMPOSITE RADAR SHOWS AN EAST-WEST BAND OF ECHOES PRODUCING IFR
VISIBILITY RAIN/SNOW MIX NOW LIFTING NORTHWARD ACROSS THE TAFS.
FURTHER SOUTH THOUGH, PRECIPITATION HAS ALREADY ENDED - AT LEAST
TEMPORARILY AT RUT. VISIBILITIES SHOULD BEGIN TO IMPROVE FROM
SOUTH TO NORTH AS FRONT LIFTS NORTH THROUGH 00Z WEDNESDAY. EXPECT
A BREAK IN PRECIPITATION AND IMPROVEMENT IN VISBYS UNTIL AROUND
00-02Z. APPROACHING MOISTURE FROM THE OHIO VALLEY IS PROGGED BY
THE HRRR TO SHIFT INTO RUT, WHILE WARM FRONT TO THE NORTH BEGINS
ITS SAG SOUTHWARD. THAT SHOULD PRODUCE ANOTHER PERIOD OF MVFR TO
IFR VISIBILITIES IN RAIN/SNOW. WINDS LIGHT/VARIABLE BECOMING
SOUTH UNDER 10 KTS, THEN SHIFTING TO NORTH UNDER 10 KTS OVERNIGHT
AS BOUNDARY SAGS BACK SOUTHWARD.
FOR TUESDAY, ANY LINGERING PRECIPITATION WILL REMAIN PRIMARILY AT
RUT IN THE MORNING HOURS. EXPECT MOSTLY VFR CONDITIONS ELSEWHERE.
OUTLOOK 18Z TUESDAY THROUGH FRIDAY...
18Z TUESDAY THROUGH 18Z WEDNESDAY...TRENDING VFR AT ALL TERMINALS
WITH HIGH PRESSURE BUILDING SOUTH INTO THE AREA.
18Z WEDNESDAY THROUGH 06Z THURSDAY...TRENDING MVFR/OCCNL IFR IN
PERIODS OF LIGHT RAIN/SNOW WITH ADDITIONAL ENERGY RIDING ALONG
SEMI-STATIONARY FRONT ACROSS THE REGION.
06Z THURSDAY THROUGH 00Z FRIDAY...TRENDING VFR WITH HIGH PRESSURE,
THOUGH BKN/OVC CIGS STILL LIKELY.
00Z FRIDAY THROUGH 00Z SATURDAY...IFR/MVFR IN STEADIER RAIN AND
SNOW SHOWERS WITH ADDITIONAL ENERGY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...WGH
NEAR TERM...MUCCILLI
SHORT TERM...WGH
LONG TERM...LOCONTO
AVIATION...LOCONTO
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
243 PM EDT SUN APR 5 2015
.SYNOPSIS...
SNOW WILL CONTINUE ACROSS SOUTH CENTRAL NEW YORK AND NORTHERN
PENNSYLVANIA THIS AFTERNOON, BUT WILL CHANGE OVER TO MOSTLY RAIN
IN LOWER ELEVATIONS. TONIGHT LIGHT SNOW WILL CONTINUE MOSTLY IN
CENTRAL NEW YORK. MONDAY WILL BE MAINLY DRY BEFORE ANOTHER SYSTEM
BRINGS LIGHT RAIN ON TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NOON UPDATE...
MINOR CHANGES. SNOW IS HERE AND ACCUMULATING NICELY. A PUSH NOW
INTO NE PA SO UPPED POPS THERE. WITH THE SNOW BECOME STEADY
TEMPERATURES HAVE DROPPED SO ADJUSTED HOURLY TEMPS.
400 AM UPDATE...
AN INTERESTING FORECAST ACROSS OUR AREA TODAY WITH BOTH WIND AND
SNOW CONCERNS.
AN AREA OF MOISTURE NOW ALONG AN EAST/WEST FRONTAL BOUNDARY OVER
THE GREAT LAKES WILL MOVE EAST-SOUTHEAST THIS MORNING. WITH AN
INTENSE TEMPERATURE ALREADY PRESENT (20S NORTHERN LOWER MICHIGAN,
40S SOUTHERN LOWER MICHIGAN) AND COOLING CLOUD TOPS, ALL SIGNS
POINT TO A NARROW BUT INTENSE AREA OF HEAVIER PRECIPITATION IN OUR
AREA BY LATE MORNING. IN ADDITION WITH THE ORIENTATION OF THE
FRONT BEING WEST TO EAST, OUR PRECIPITATION WILL LIKELY BE FOCUSED
IN THE SAME AREA FOR A LONG PERIOD OF TIME. FOLKS REMOVED FROM
THIS BOUNDARY WELL TO OUR NORTH AND SOUTH MAY SAY WHATS THE WORRY?
IN THE MIDDLE HOWEVER, COOL TEMPS ALOFT WITH STRONG LIFT WILL BE
ENOUGH TO OVERCOME A STRONG EARLY APRIL SUN TO PRODUCE HEAVY
SNOWFALL RATES EARLY TODAY. BUFKIT PROFILES SHOW GOOD RH AND LIFT
INTO THE DENDRITIC LAYER, SHOWING THIS POTENTIAL FOR A HEAVIER
BURST OF SNOW. FURTHER SUPPORTING THE NOTION THAT THIS BAND WILL
NOT BE VERY WIDE NORTH SOUTH, BUT INSTEAD VERY ELONGATED, IS THE
DIFFERENCES IN OMEGA VALUES FROM FORECAST POINT TO FORECAST POINT.
I WENT WITH MOSTLY ALL SNOW THROUGH MIDDAY FROM NEAR THE NY/PA
LINE NORTH, WITH 850S BELOW 0C AND STRONG LIFT HELPING TO COOL THE
COLUMN. BY AFTERNOON BOUNDARY LAYER TEMPS WILL WARM ENOUGH FOR A
TRANSITION TO RAIN FIRST IN THE VALLEYS AND EVENTUALLY LATER OVER
THE HILLS. STILL CONCERNED A FEW OF THE HIGHER ELEVATIONS MAY HAVE
TROUBLE SWITCHING OVER TO RAIN, GIVEN SUCH STRONG LIFT IN THE
COLUMN. ITS VERY POSSIBLE WE MAY HAVE MODERATE SNOWFALL RATES EVEN
WITH SURFACE TEMPS IN THE 34-36 RANGE. I WENT A COATING TO 2
INCHES BY AFTERNOON ACROSS THE FINGER LAKES, SOUTHERN TIER, AND
EXTREME NORTHERN TIER OF PA. A FEW 3 INCH VALUES ARE POSSIBLE
ESPECIALLY OVER THE HIGHER TERRAIN WHERE THE TRANSITION TO RAIN
WILL TAKE LONGER. WHILE MOST OF THE ACCUMULATION WILL OCCUR TO
GRASSY SURFACES WITH MAINLY JUST WET ROADS, SOME SLUSHY SPOTS
CAN`T BE RULED OUT DURING THE HEAVIER PERIODS OF SNOW. AGAIN MOST
LIKELY HIGHER TERRAIN/SHADY SPOTS, ELEVATED BRIDGES, ETC.
HIGHLIGHTED THIS IN OUR HWO.
FARTHER SOUTH TOWARD THE WYOMING VALLEY AND THE POCONOS MOST OF
THE DAY MAY REMAIN DRY BUT VERY WINDY. HRRR WIND GUSTS, WHICH DID
VERY WELL YESTERDAY, SHOW GUSTS OVER 30 MPH THROUGH AFTERNOON. RAP
VALUES ARE ALSO SIMILAR. I INCREASED WIND SPEEDS HERE AND
MENTIONED THIS IN THE HWO. WOULD NOT RULE OUT A FEW POWER OUTAGES
IN THIS AREA WITH AN INVERTED V SOUNDING AND STEEP LAPSE RATES TO
600 MB SCREAMING WIND POTENTIAL. WILL PASS ONTO THE DAY SHIFT THIS
POTENTIAL IN CASE A SHORT TERM WIND ADVISORY IS NEEDED. FOR NOW
HELD OFF ON ANYTHING WITH COLLABORATION FROM SURROUNDING OFFICES
AND NAM/GFS MOMENTUM TRANSFER VALUES NOT BEING QUITE AS HIGH AS HI
RES GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
400 AM UPDATE...
EAST/WEST BOUNDARY MENTIONED ABOVE SLOWLY MOVES NORTH TONIGHT. THE
DYNAMICS ARE BEST EARLY IN THE NIGHT BUT GRADUALLY FADE AS
PRECIPITATION SHIELD LIFTS NORTH LATE. UP TO ANOTHER INCH OR SO OF
SNOW IS POSSIBLE AGAIN TONIGHT, BUT THE AXIS WILL BE SLIGHTLY
SHIFTED A FEW COUNTIES NORTH. WHILE SHOWERS CAN`T BE RULED OUT
MOST OF MONDAY INTO MONDAY NIGHT ACROSS CENTRAL NY, MOST OF THIS
PERIOD WILL EXPERIENCE MANY STRETCHES OF DRY WEATHER. AT THE SAME
TIME TEMPS GRADUALLY WARM UP SO ASIDE FROM SOME WET SNOW ACROSS
NORTHERN ONEIDA COUNTY MONDAY EVENING, P-TYPE CONCERNS ARE MUCH
LESS. TEMPS WILL VARY WIDELY OVER OUR AREA WITH 60S IN NEPA, BUT
ONLY IN THE 40S ACROSS NORTHERN ONEIDA COUNTY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
245 PM EDT UPDATE...
CLOSELY FOLLOWED WPC GUIDANCE...
A WET PATTERN CONTINUES AS BROAD SW FLOW ALOFT PREVAILS THROUGHOUT
THE EXTENDED FORECAST PERIOD. THIS PATTERN ALOFT ALLOWS FOR MULTP
SHORTWAVES WITHIN THE UPPR LVL FLOW TO PASS OVER THE REGION BRINGING
A CHANCE FOR RAIN SHOWERS EACH DAY. ATTM... THE BEST CHANCE FOR RAIN
SHOWERS OVER THE REGION WILL BE THURS NIGHT THRU FRIDAY NIGHT. AS WE
ARE AT THE TAIL END OF WINTER... THERE IS STILL A CHANCE AT NIGHT
THAT SOME OF THESE SHOWERS COULD TRANSITION OVER TO SNOW. NO MAJOR
ACCUMULATIONS ARE EXPECTED THROUGH THE EXTENDED. TEMPERATURES DURING
THIS TIME FRAME ARE EXPECTED TO BE AT OR ABOVE THE SEASONAL NORM.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
A FRONTAL BOUNDARY MOVED OVER THE REGION THIS MORNING AND RAIN
AND SNOW SHOWERS CURRENTLY PREVAIL ALONG AND BEHIND IT. IFR SNOW
SHOWERS WILL CONTINUE NORTH OF THIS BOUNDARY... AND VFR RAIN
SHOWERS WILL PREVAIL SOUTH OF THIS BOUNDARY. WINDS WILL BE FAIRLY
LIGHT AS CLOUD COVERAGE IS PREVENTING MIXING. THIS BOUNDARY WILL
SLOWLY DRIFT NORTHWARD TODAY. ACTIVITY WILL DECREASE THIS
EVENING... WITH MOSTLY CLOUDY SKIES WILL PERSISTING WELL THROUGH
THE OVERNIGHT. ACTIVITY WILL INCREASE AGAIN EARLY TOMORROW MORNING
AS ANOTHER WAVE MOVES ACROSS THE FRONTAL BOUNDARY. THE SECOND
ROUND OF SHOWER SHOULD IMPACT KSYR AND KRME. A LOW STRATUS DECK
WILL DEVELOP LATE TONIGHT OVER KELM... KBGM AND KITH. CONDITIONS
SHOULD IMPROVE SHORTLY AFTER 12Z AS THE FRONT LIFTS WELL NORTH OF
THESE SITES. KAVP IS EXPECTED TO REMAIN VFR AS THE BOUNDARY IS
WELL TO ITS NORTH.
.OUTLOOK...
MON AFTERNOON-FRI...BUSY PATTERN WITH INTERMITTENT RESTRICTIONS FROM -SHRA
AS MULTIPLE WAVES MOVE THROUGH THE REGION. COULD BE MIXED WITH
-SHSN.
&&
.HYDROLOGY...
NOON SUNDAY UPDATE...
VESTAL AND CONKLIN ON THE SUSQUEHANNA RIVER HAVE FALLEN NICELY AND
ARE NOW WELL BELOW FLOOD STAGE. RIVER WARNINGS CANCELLED THERE AT
6 AM. CORTLAND WAS HIGHER ABOVE FLOOD STAGE LAST NIGHT AND IS
FALLING SLOWER. IT SHOULD FALL BELOW FLOOD STAGE BETWEEN 2 AND 4
PM.
REST OF RIVER POINTS STAYED BELOW FLOOD STAGE AND ARE ALSO FALLING
NOW.
MOSTLY SNOW TODAY INTO MONDAY WILL HAVE LITTLE RUNOFF. BIGGER
PROBLEM IS THE RAIN ON TUESDAY. THIS COMBINED WITH WARM
TEMPERATURES WILL CAUSE MORE SNOWMELT RUNOFF. RIVER FORECASTS BACK
TO MINOR FLOOD FOR CORTLAND AND SHERBURNE...AND PROBABLY VESTAL
AND CONKLIN AGAIN. FLOOD STAGE REACHED LATE TUE NGT AND WED.
CONFIDENCE MEDIUM AND MAGNITUDE OF FLOOD WILL OBVIOUSLY DEPEND ON
HOW MUCH RUNOFF IS GENERATED. SNOWMELT IS MORE UNCERTAIN GIVEN THE
EXTENT AND AMOUNT THAT WAS MELTED OFF THE LAST FEW DAYS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN/TAC
NEAR TERM...HEDEN/TAC
SHORT TERM...HEDEN
LONG TERM...KAH
AVIATION...KAH
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
149 PM EDT SUN APR 5 2015
.SYNOPSIS...
SNOW WILL CONTINUE ACROSS SOUTH CENTRAL NEW YORK AND NORTHERN
PENNSYLVANIA THIS AFTERNOON, BUT WILL CHANGE OVER TO MOSTLY RAIN
IN LOWER ELEVATIONS. TONIGHT LIGHT SNOW WILL CONTINUE MOSTLY IN
CENTRAL NEW YORK. MONDAY WILL BE MAINLY DRY BEFORE ANOTHER SYSTEM
BRINGS LIGHT RAIN ON TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NOON UPDATE...
MINOR CHANGES. SNOW IS HERE AND ACCUMULATING NICELY. A PUSH NOW
INTO NE PA SO UPPED POPS THERE. WITH THE SNOW BECOME STEADY
TEMPERATURES HAVE DROPPED SO ADJUSTED HOURLY TEMPS.
400 AM UPDATE...
AN INTERESTING FORECAST ACROSS OUR AREA TODAY WITH BOTH WIND AND
SNOW CONCERNS.
AN AREA OF MOISTURE NOW ALONG AN EAST/WEST FRONTAL BOUNDARY OVER
THE GREAT LAKES WILL MOVE EAST-SOUTHEAST THIS MORNING. WITH AN
INTENSE TEMPERATURE ALREADY PRESENT (20S NORTHERN LOWER MICHIGAN,
40S SOUTHERN LOWER MICHIGAN) AND COOLING CLOUD TOPS, ALL SIGNS
POINT TO A NARROW BUT INTENSE AREA OF HEAVIER PRECIPITATION IN OUR
AREA BY LATE MORNING. IN ADDITION WITH THE ORIENTATION OF THE
FRONT BEING WEST TO EAST, OUR PRECIPITATION WILL LIKELY BE FOCUSED
IN THE SAME AREA FOR A LONG PERIOD OF TIME. FOLKS REMOVED FROM
THIS BOUNDARY WELL TO OUR NORTH AND SOUTH MAY SAY WHATS THE WORRY?
IN THE MIDDLE HOWEVER, COOL TEMPS ALOFT WITH STRONG LIFT WILL BE
ENOUGH TO OVERCOME A STRONG EARLY APRIL SUN TO PRODUCE HEAVY
SNOWFALL RATES EARLY TODAY. BUFKIT PROFILES SHOW GOOD RH AND LIFT
INTO THE DENDRITIC LAYER, SHOWING THIS POTENTIAL FOR A HEAVIER
BURST OF SNOW. FURTHER SUPPORTING THE NOTION THAT THIS BAND WILL
NOT BE VERY WIDE NORTH SOUTH, BUT INSTEAD VERY ELONGATED, IS THE
DIFFERENCES IN OMEGA VALUES FROM FORECAST POINT TO FORECAST POINT.
I WENT WITH MOSTLY ALL SNOW THROUGH MIDDAY FROM NEAR THE NY/PA
LINE NORTH, WITH 850S BELOW 0C AND STRONG LIFT HELPING TO COOL THE
COLUMN. BY AFTERNOON BOUNDARY LAYER TEMPS WILL WARM ENOUGH FOR A
TRANSITION TO RAIN FIRST IN THE VALLEYS AND EVENTUALLY LATER OVER
THE HILLS. STILL CONCERNED A FEW OF THE HIGHER ELEVATIONS MAY HAVE
TROUBLE SWITCHING OVER TO RAIN, GIVEN SUCH STRONG LIFT IN THE
COLUMN. ITS VERY POSSIBLE WE MAY HAVE MODERATE SNOWFALL RATES EVEN
WITH SURFACE TEMPS IN THE 34-36 RANGE. I WENT A COATING TO 2
INCHES BY AFTERNOON ACROSS THE FINGER LAKES, SOUTHERN TIER, AND
EXTREME NORTHERN TIER OF PA. A FEW 3 INCH VALUES ARE POSSIBLE
ESPECIALLY OVER THE HIGHER TERRAIN WHERE THE TRANSITION TO RAIN
WILL TAKE LONGER. WHILE MOST OF THE ACCUMULATION WILL OCCUR TO
GRASSY SURFACES WITH MAINLY JUST WET ROADS, SOME SLUSHY SPOTS
CAN`T BE RULED OUT DURING THE HEAVIER PERIODS OF SNOW. AGAIN MOST
LIKELY HIGHER TERRAIN/SHADY SPOTS, ELEVATED BRIDGES, ETC.
HIGHLIGHTED THIS IN OUR HWO.
FARTHER SOUTH TOWARD THE WYOMING VALLEY AND THE POCONOS MOST OF
THE DAY MAY REMAIN DRY BUT VERY WINDY. HRRR WIND GUSTS, WHICH DID
VERY WELL YESTERDAY, SHOW GUSTS OVER 30 MPH THROUGH AFTERNOON. RAP
VALUES ARE ALSO SIMILAR. I INCREASED WIND SPEEDS HERE AND
MENTIONED THIS IN THE HWO. WOULD NOT RULE OUT A FEW POWER OUTAGES
IN THIS AREA WITH AN INVERTED V SOUNDING AND STEEP LAPSE RATES TO
600 MB SCREAMING WIND POTENTIAL. WILL PASS ONTO THE DAY SHIFT THIS
POTENTIAL IN CASE A SHORT TERM WIND ADVISORY IS NEEDED. FOR NOW
HELD OFF ON ANYTHING WITH COLLABORATION FROM SURROUNDING OFFICES
AND NAM/GFS MOMENTUM TRANSFER VALUES NOT BEING QUITE AS HIGH AS HI
RES GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
400 AM UPDATE...
EAST/WEST BOUNDARY MENTIONED ABOVE SLOWLY MOVES NORTH TONIGHT. THE
DYNAMICS ARE BEST EARLY IN THE NIGHT BUT GRADUALLY FADE AS
PRECIPITATION SHIELD LIFTS NORTH LATE. UP TO ANOTHER INCH OR SO OF
SNOW IS POSSIBLE AGAIN TONIGHT, BUT THE AXIS WILL BE SLIGHTLY
SHIFTED A FEW COUNTIES NORTH. WHILE SHOWERS CAN`T BE RULED OUT
MOST OF MONDAY INTO MONDAY NIGHT ACROSS CENTRAL NY, MOST OF THIS
PERIOD WILL EXPERIENCE MANY STRETCHES OF DRY WEATHER. AT THE SAME
TIME TEMPS GRADUALLY WARM UP SO ASIDE FROM SOME WET SNOW ACROSS
NORTHERN ONEIDA COUNTY MONDAY EVENING, P-TYPE CONCERNS ARE MUCH
LESS. TEMPS WILL VARY WIDELY OVER OUR AREA WITH 60S IN NEPA, BUT
ONLY IN THE 40S ACROSS NORTHERN ONEIDA COUNTY.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
445 AM UPDATE...
BUSY WET PATTERN CONTINUES. SURFACE BOUNDARY WILL SAG SOUTHWARD
TUESDAY THROUGH WEDNESDAY WITH PASSING WAVES ALOFT...FOLLOWED BY
WARM AIR ADVECTION THURSDAY-FRIDAY COURTESY OF MOIST SOUTHWEST FLOW
IN THE UPPER LEVELS. ALMOST EXCLUSIVELY RAIN FOR PRECIP
TYPE...WITH THE LITTLE BIT OF MIXED SNOW CHANCES MAINLY RELEGATED
TO HIGHER ELEVATIONS OF CENTRAL NY EARLIER IN THE PERIOD. GRIDS
ADJUSTED TOWARDS LATEST WPC GUIDANCE AND/OR MODEL TRENDS. WETTEST
DAYS APPEAR TO BE TUE-TUE NIGHT WITH AREAL AVERAGE OF ROUGHLY ONE
TO TWO THIRDS OF AN INCH...AND FRI-FRI NIGHT AS A COLD FRONT DRAPES
THROUGH WITH A MOIST ATMOSPHERE /PWATS IN EXCESS OF AN INCH IN GFS/.
PREVIOUS DISCUSSION...
CLOSELY FOLLOWED WPC GUIDANCE. EXTENDED BRINGS TRUTH TO THE
MEANING... APRIL SHOWERS... BRING MAY FLOWERS. THE EXTENDED LOOKS
VERY ACTIVE AND WET. MULTIPLE WAVES ARE EXPECTED TO PASS OVER THE
REGION DURING THE EXTENDED PERIOD BRINGING THE CHANCE FOR SHOWERS.
CONFIDENCE INCREASES ON ANOTHER STORM SYSTEM IMPACTING THE REGION
TUES NIGHT INTO WED. OVERALL... TRENDS APPEAR TO BE RAIN DURING
THE AFTERNOON AND RAIN/SNOW MIX DURING THE OVERNIGHT. THE CHANCE
FOR SHOWERS WILL EXIST EACH DAY. AT LEAST ON THE UPSIDE... TEMPS
DURING THE EXTENDED ARE EXPECTED TO REMAIN AT THE SEASONAL NORM...
AND A POSSIBLE WARMING TREND MAY OCCUR NEXT WEEKEND.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
A FRONTAL BOUNDARY MOVED OVER THE REGION THIS MORNING AND RAIN
AND SNOW SHOWERS CURRENTLY PREVAIL ALONG AND BEHIND IT. IFR SNOW
SHOWERS WILL CONTINUE NORTH OF THIS BOUNDARY... AND VFR RAIN
SHOWERS WILL PREVAIL SOUTH OF THIS BOUNDARY. WINDS WILL BE FAIRLY
LIGHT AS CLOUD COVERAGE IS PREVENTING MIXING. THIS BOUNDARY WILL
SLOWLY DRIFT NORTHWARD TODAY. ACTIVITY WILL DECREASE THIS
EVENING... WITH MOSTLY CLOUDY SKIES WILL PERSISTING WELL THROUGH
THE OVERNIGHT. ACTIVITY WILL INCREASE AGAIN EARLY TOMORROW MORNING
AS ANOTHER WAVE MOVES ACROSS THE FRONTAL BOUNDARY. THE SECOND
ROUND OF SHOWER SHOULD IMPACT KSYR AND KRME. A LOW STRATUS DECK
WILL DEVELOP LATE TONIGHT OVER KELM... KBGM AND KITH. CONDITIONS
SHOULD IMPROVE SHORTLY AFTER 12Z AS THE FRONT LIFTS WELL NORTH OF
THESE SITES. KAVP IS EXPECTED TO REMAIN VFR AS THE BOUNDARY IS
WELL TO ITS NORTH.
.OUTLOOK...
MON AFTERNOON-FRI...BUSY PATTERN WITH INTERMITTENT RESTRICTIONS FROM -SHRA
AS MULTIPLE WAVES MOVE THROUGH THE REGION. COULD BE MIXED WITH
-SHSN.
&&
.HYDROLOGY...
NOON SUNDAY UPDATE...
VESTAL AND CONKLIN ON THE SUSQUEHANNA RIVER HAVE FALLEN NICELY AND
ARE NOW WELL BELOW FLOOD STAGE. RIVER WARNINGS CANCELLED THERE AT
6 AM. CORTLAND WAS HIGHER ABOVE FLOOD STAGE LAST NIGHT AND IS
FALLING SLOWER. IT SHOULD FALL BELOW FLOOD STAGE BETWEEN 2 AND 4
PM.
REST OF RIVER POINTS STAYED BELOW FLOOD STAGE AND ARE ALSO FALLING
NOW.
MOSTLY SNOW TODAY INTO MONDAY WILL HAVE LITTLE RUNOFF. BIGGER
PROBLEM IS THE RAIN ON TUESDAY. THIS COMBINED WITH WARM
TEMPERATURES WILL CAUSE MORE SNOWMELT RUNOFF. RIVER FORECASTS BACK
TO MINOR FLOOD FOR CORTLAND AND SHERBURNE...AND PROBABLY VESTAL
AND CONKLIN AGAIN. FLOOD STAGE REACHED LATE TUE NGT AND WED.
CONFIDENCE MEDIUM AND MAGNITUDE OF FLOOD WILL OBVIOUSLY DEPEND ON
HOW MUCH RUNOFF IS GENERATED. SNOWMELT IS MORE UNCERTAIN GIVEN THE
EXTENT AND AMOUNT THAT WAS MELTED OFF THE LAST FEW DAYS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN/TAC
NEAR TERM...HEDEN/TAC
SHORT TERM...HEDEN
LONG TERM...MDP
AVIATION...KAH
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1231 PM EDT SUN APR 5 2015
.SYNOPSIS...
SNOW WILL CONTINUE ACROSS SOUTH CENTRAL NEW YORK AND NORTHERN
PENNSYLVANIA THIS AFTERNOON, BUT WILL CHANGE OVER TO MOSTLY RAIN
IN LOWER ELEVATIONS. TONIGHT LIGHT SNOW WILL CONTINUE MOSTLY IN
CENTRAL NEW YORK. MONDAY WILL BE MAINLY DRY BEFORE ANOTHER SYSTEM
BRINGS LIGHT RAIN ON TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NOON UPDATE...
MINOR CHANGES. SNOW IS HERE AND ACCUMULATING NICELY. A PUSH NOW
INTO NE PA SO UPPED POPS THERE. WITH THE SNOW BECOME STEADY
TEMPERATURES HAVE DROPPED SO ADJUSTED HOURLY TEMPS.
400 AM UPDATE...
AN INTERESTING FORECAST ACROSS OUR AREA TODAY WITH BOTH WIND AND
SNOW CONCERNS.
AN AREA OF MOISTURE NOW ALONG AN EAST/WEST FRONTAL BOUNDARY OVER
THE GREAT LAKES WILL MOVE EAST-SOUTHEAST THIS MORNING. WITH AN
INTENSE TEMPERATURE ALREADY PRESENT (20S NORTHERN LOWER MICHIGAN,
40S SOUTHERN LOWER MICHIGAN) AND COOLING CLOUD TOPS, ALL SIGNS
POINT TO A NARROW BUT INTENSE AREA OF HEAVIER PRECIPITATION IN OUR
AREA BY LATE MORNING. IN ADDITION WITH THE ORIENTATION OF THE
FRONT BEING WEST TO EAST, OUR PRECIPITATION WILL LIKELY BE FOCUSED
IN THE SAME AREA FOR A LONG PERIOD OF TIME. FOLKS REMOVED FROM
THIS BOUNDARY WELL TO OUR NORTH AND SOUTH MAY SAY WHATS THE WORRY?
IN THE MIDDLE HOWEVER, COOL TEMPS ALOFT WITH STRONG LIFT WILL BE
ENOUGH TO OVERCOME A STRONG EARLY APRIL SUN TO PRODUCE HEAVY
SNOWFALL RATES EARLY TODAY. BUFKIT PROFILES SHOW GOOD RH AND LIFT
INTO THE DENDRITIC LAYER, SHOWING THIS POTENTIAL FOR A HEAVIER
BURST OF SNOW. FURTHER SUPPORTING THE NOTION THAT THIS BAND WILL
NOT BE VERY WIDE NORTH SOUTH, BUT INSTEAD VERY ELONGATED, IS THE
DIFFERENCES IN OMEGA VALUES FROM FORECAST POINT TO FORECAST POINT.
I WENT WITH MOSTLY ALL SNOW THROUGH MIDDAY FROM NEAR THE NY/PA
LINE NORTH, WITH 850S BELOW 0C AND STRONG LIFT HELPING TO COOL THE
COLUMN. BY AFTERNOON BOUNDARY LAYER TEMPS WILL WARM ENOUGH FOR A
TRANSITION TO RAIN FIRST IN THE VALLEYS AND EVENTUALLY LATER OVER
THE HILLS. STILL CONCERNED A FEW OF THE HIGHER ELEVATIONS MAY HAVE
TROUBLE SWITCHING OVER TO RAIN, GIVEN SUCH STRONG LIFT IN THE
COLUMN. ITS VERY POSSIBLE WE MAY HAVE MODERATE SNOWFALL RATES EVEN
WITH SURFACE TEMPS IN THE 34-36 RANGE. I WENT A COATING TO 2
INCHES BY AFTERNOON ACROSS THE FINGER LAKES, SOUTHERN TIER, AND
EXTREME NORTHERN TIER OF PA. A FEW 3 INCH VALUES ARE POSSIBLE
ESPECIALLY OVER THE HIGHER TERRAIN WHERE THE TRANSITION TO RAIN
WILL TAKE LONGER. WHILE MOST OF THE ACCUMULATION WILL OCCUR TO
GRASSY SURFACES WITH MAINLY JUST WET ROADS, SOME SLUSHY SPOTS
CAN`T BE RULED OUT DURING THE HEAVIER PERIODS OF SNOW. AGAIN MOST
LIKELY HIGHER TERRAIN/SHADY SPOTS, ELEVATED BRIDGES, ETC.
HIGHLIGHTED THIS IN OUR HWO.
FARTHER SOUTH TOWARD THE WYOMING VALLEY AND THE POCONOS MOST OF
THE DAY MAY REMAIN DRY BUT VERY WINDY. HRRR WIND GUSTS, WHICH DID
VERY WELL YESTERDAY, SHOW GUSTS OVER 30 MPH THROUGH AFTERNOON. RAP
VALUES ARE ALSO SIMILAR. I INCREASED WIND SPEEDS HERE AND
MENTIONED THIS IN THE HWO. WOULD NOT RULE OUT A FEW POWER OUTAGES
IN THIS AREA WITH AN INVERTED V SOUNDING AND STEEP LAPSE RATES TO
600 MB SCREAMING WIND POTENTIAL. WILL PASS ONTO THE DAY SHIFT THIS
POTENTIAL IN CASE A SHORT TERM WIND ADVISORY IS NEEDED. FOR NOW
HELD OFF ON ANYTHING WITH COLLABORATION FROM SURROUNDING OFFICES
AND NAM/GFS MOMENTUM TRANSFER VALUES NOT BEING QUITE AS HIGH AS HI
RES GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
400 AM UPDATE...
EAST/WEST BOUNDARY MENTIONED ABOVE SLOWLY MOVES NORTH TONIGHT. THE
DYNAMICS ARE BEST EARLY IN THE NIGHT BUT GRADUALLY FADE AS
PRECIPITATION SHIELD LIFTS NORTH LATE. UP TO ANOTHER INCH OR SO OF
SNOW IS POSSIBLE AGAIN TONIGHT, BUT THE AXIS WILL BE SLIGHTLY
SHIFTED A FEW COUNTIES NORTH. WHILE SHOWERS CAN`T BE RULED OUT
MOST OF MONDAY INTO MONDAY NIGHT ACROSS CENTRAL NY, MOST OF THIS
PERIOD WILL EXPERIENCE MANY STRETCHES OF DRY WEATHER. AT THE SAME
TIME TEMPS GRADUALLY WARM UP SO ASIDE FROM SOME WET SNOW ACROSS
NORTHERN ONEIDA COUNTY MONDAY EVENING, P-TYPE CONCERNS ARE MUCH
LESS. TEMPS WILL VARY WIDELY OVER OUR AREA WITH 60S IN NEPA, BUT
ONLY IN THE 40S ACROSS NORTHERN ONEIDA COUNTY.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
445 AM UPDATE...
BUSY WET PATTERN CONTINUES. SURFACE BOUNDARY WILL SAG SOUTHWARD
TUESDAY THROUGH WEDNESDAY WITH PASSING WAVES ALOFT...FOLLOWED BY
WARM AIR ADVECTION THURSDAY-FRIDAY COURTESY OF MOIST SOUTHWEST FLOW
IN THE UPPER LEVELS. ALMOST EXCLUSIVELY RAIN FOR PRECIP
TYPE...WITH THE LITTLE BIT OF MIXED SNOW CHANCES MAINLY RELEGATED
TO HIGHER ELEVATIONS OF CENTRAL NY EARLIER IN THE PERIOD. GRIDS
ADJUSTED TOWARDS LATEST WPC GUIDANCE AND/OR MODEL TRENDS. WETTEST
DAYS APPEAR TO BE TUE-TUE NIGHT WITH AREAL AVERAGE OF ROUGHLY ONE
TO TWO THIRDS OF AN INCH...AND FRI-FRI NIGHT AS A COLD FRONT DRAPES
THROUGH WITH A MOIST ATMOSPHERE /PWATS IN EXCESS OF AN INCH IN GFS/.
PREVIOUS DISCUSSION...
CLOSELY FOLLOWED WPC GUIDANCE. EXTENDED BRINGS TRUTH TO THE
MEANING... APRIL SHOWERS... BRING MAY FLOWERS. THE EXTENDED LOOKS
VERY ACTIVE AND WET. MULTIPLE WAVES ARE EXPECTED TO PASS OVER THE
REGION DURING THE EXTENDED PERIOD BRINGING THE CHANCE FOR SHOWERS.
CONFIDENCE INCREASES ON ANOTHER STORM SYSTEM IMPACTING THE REGION
TUES NIGHT INTO WED. OVERALL... TRENDS APPEAR TO BE RAIN DURING
THE AFTERNOON AND RAIN/SNOW MIX DURING THE OVERNIGHT. THE CHANCE
FOR SHOWERS WILL EXIST EACH DAY. AT LEAST ON THE UPSIDE... TEMPS
DURING THE EXTENDED ARE EXPECTED TO REMAIN AT THE SEASONAL NORM...
AND A POSSIBLE WARMING TREND MAY OCCUR NEXT WEEKEND.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
12Z UPDATE...
VIGOROUS SHORTWAVE EARLIER IN THE NIGHT BROUGHT A QUICK SHOT OF
SNOW FOR KITH-KBGM-KELM...BUT IS NOW GONE. HOWEVER...ATTENTION
ALREADY TURNS TO NEXT INBOUND WAVE WHICH WILL OVERSPREAD THE AREA
THIS MORNING...WITH RESTRICTIONS CONTINUING THIS AFTERNOON-
EVENING. NARROW CORRIDOR OF HIGHER IMPACT SNOW MOST PROBABLE FOR
KITH-KELM-KBGM...THOUGH IN TIME MIXING WITH RAIN ESPECIALLY KELM.
KSYR-KRME ON NORTHERN EDGE OF PRECIP...ONLY HIGHER END MVFR CIG
AND VIS FIGURED FOR NOW BUT THIS WILL NEED TO BE WATCHED
CLOSELY...IF PRECIP BAND SHIFTS JUST A LITTLE NORTHWARD THEN IFR
RESTRICTIONS COULD RESULT. MEANWHILE...NOT EXPECTING ANY
RESTRICTIONS FOR KAVP...THOUGH SCT -SHRA WILL PROBABLY SKIM
THROUGH EARLY-MID AFTERNOON. WINDS MAINLY WESTERLY 10 KTS OR
LESS...BECOMING VARIABLE LATE AFTERNOON-EVENING...EXCEPT SOUTH OF
THE FRONTAL BOUNDARY KAVP WILL HAVE WSW-W WINDS 10-15 KTS WITH
GUSTS 25-30 KTS THIS AFTERNOON.
.OUTLOOK...
LATE SUN NIGHT-THURS...BUSY PATTERN WITH INTERMITTENT
RESTRICTIONS FROM -SHRA AS MULTIPLE WAVES MOVE THROUGH THE REGION.
COULD BE MIXED WITH -SHSN AT TIMES MAINLY KSYR-KRME.
&&
.HYDROLOGY...
NOON SUNDAY UPDATE...
VESTAL AND CONKLIN ON THE SUSQUEHANNA RIVER HAVE FALLEN NICELY AND
ARE NOW WELL BELOW FLOOD STAGE. RIVER WARNINGS CANCELLED THERE AT
6 AM. CORTLAND WAS HIGHER ABOVE FLOOD STAGE LAST NIGHT AND IS
FALLING SLOWER. IT SHOULD FALL BELOW FLOOD STAGE BETWEEN 2 AND 4
PM.
REST OF RIVER POINTS STAYED BELOW FLOOD STAGE AND ARE ALSO FALLING
NOW.
MOSTLY SNOW TODAY INTO MONDAY WILL HAVE LITTLE RUNOFF. BIGGER
PROBLEM IS THE RAIN ON TUESDAY. THIS COMBINED WITH WARM
TEMPERATURES WILL CAUSE MORE SNOWMELT RUNOFF. RIVER FORECASTS BACK
TO MINOR FLOOD FOR CORTLAND AND SHERBURNE...AND PROBABLY VESTAL
AND CONKLIN AGAIN. FLOOD STAGE REACHED LATE TUE NGT AND WED.
CONFIDENCE MEDIUM AND MAGNITUDE OF FLOOD WILL OBVIOUSLY DEPEND ON
HOW MUCH RUNOFF IS GENERATED. SNOWMELT IS MORE UNCERTAIN GIVEN THE
EXTENT AND AMOUNT THAT WAS MELTED OFF THE LAST FEW DAYS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN/TAC
NEAR TERM...HEDEN/TAC
SHORT TERM...HEDEN
LONG TERM...MDP
AVIATION...MDP
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
649 AM EDT SUN APR 5 2015
.SYNOPSIS...
SNOW WILL OVERSPREAD SOUTHERN NEW YORK AND NORTHERN PENNSYLVANIA
THIS MORNING. BY AFTERNOON THE SNOW WILL CHANGE OVER TO MOSTLY
RAIN IN LOWER ELEVATIONS, BUT SNOW MAY LINGER ON THE HILLTOPS. MONDAY
WILL BE MAINLY DRY BEFORE ANOTHER SYSTEM BRINGS LIGHT RAIN ON
TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
400 AM UPDATE...
AN INTERESTING FORECAST ACROSS OUR AREA TODAY WITH BOTH WIND AND
SNOW CONCERNS.
AN AREA OF MOISTURE NOW ALONG AN EAST/WEST FRONTAL BOUNDARY OVER THE GREAT
LAKES WILL MOVE EAST-SOUTHEAST THIS MORNING. WITH AN INTENSE TEMPERATURE
ALREADY PRESENT (20S NORTHERN LOWER MICHIGAN, 40S SOUTHERN LOWER
MICHIGAN) AND COOLING CLOUD TOPS, ALL SIGNS POINT TO A NARROW BUT
INTENSE AREA OF HEAVIER PRECIPITATION IN OUR AREA BY LATE MORNING.
IN ADDITION WITH THE ORIENTATION OF THE FRONT BEING WEST TO EAST,
OUR PRECIPITATION WILL LIKELY BE FOCUSED IN THE SAME AREA FOR A
LONG PERIOD OF TIME. FOLKS REMOVED FROM THIS BOUNDARY WELL TO OUR
NORTH AND SOUTH MAY SAY WHATS THE WORRY? IN THE MIDDLE HOWEVER,
COOL TEMPS ALOFT WITH STRONG LIFT WILL BE ENOUGH TO OVERCOME A
STRONG EARLY APRIL SUN TO PRODUCE HEAVY SNOWFALL RATES EARLY
TODAY. BUFKIT PROFILES SHOW GOOD RH AND LIFT INTO THE DENDRITIC
LAYER, SHOWING THIS POTENTIAL FOR A HEAVIER BURST OF SNOW. FURTHER
SUPPORTING THE NOTION THAT THIS BAND WILL NOT BE VERY WIDE NORTH
SOUTH, BUT INSTEAD VERY ELONGATED, IS THE DIFFERENCES IN OMEGA
VALUES FROM FORECAST POINT TO FORECAST POINT. I WENT WITH MOSTLY
ALL SNOW THROUGH MIDDAY FROM NEAR THE NY/PA LINE NORTH, WITH 850S
BELOW 0C AND STRONG LIFT HELPING TO COOL THE COLUMN. BY AFTERNOON
BOUNDARY LAYER TEMPS WILL WARM ENOUGH FOR A TRANSITION TO RAIN
FIRST IN THE VALLEYS AND EVENTUALLY LATER OVER THE HILLS. STILL
CONCERNED A FEW OF THE HIGHER ELEVATIONS MAY HAVE TROUBLE
SWITCHING OVER TO RAIN, GIVEN SUCH STRONG LIFT IN THE COLUMN. ITS
VERY POSSIBLE WE MAY HAVE MODERATE SNOWFALL RATES EVEN WITH
SURFACE TEMPS IN THE 34-36 RANGE. I WENT A COATING TO 2 INCHES BY
AFTERNOON ACROSS THE FINGER LAKES, SOUTHERN TIER, AND EXTREME
NORTHERN TIER OF PA. A FEW 3 INCH VALUES ARE POSSIBLE ESPECIALLY
OVER THE HIGHER TERRAIN WHERE THE TRANSITION TO RAIN WILL TAKE
LONGER. WHILE MOST OF THE ACCUMULATION WILL OCCUR TO GRASSY
SURFACES WITH MAINLY JUST WET ROADS, SOME SLUSHY SPOTS CAN`T BE
RULED OUT DURING THE HEAVIER PERIODS OF SNOW. AGAIN MOST LIKELY
HIGHER TERRAIN/SHADY SPOTS, ELEVATED BRIDGES, ETC. HIGHLIGHTED
THIS IN OUR HWO.
FARTHER SOUTH TOWARD THE WYOMING VALLEY AND THE POCONOS MOST OF
THE DAY MAY REMAIN DRY BUT VERY WINDY. HRRR WIND GUSTS, WHICH DID
VERY WELL YESTERDAY, SHOW GUSTS OVER 30 MPH THROUGH AFTERNOON. RAP
VALUES ARE ALSO SIMILAR. I INCREASED WIND SPEEDS HERE AND
MENTIONED THIS IN THE HWO. WOULD NOT RULE OUT A FEW POWER OUTAGES
IN THIS AREA WITH AN INVERTED V SOUNDING AND STEEP LAPSE RATES TO
600 MB SCREAMING WIND POTENTIAL. WILL PASS ONTO THE DAY SHIFT THIS
POTENTIAL IN CASE A SHORT TERM WIND ADVISORY IS NEEDED. FOR NOW
HELD OFF ON ANYTHING WITH COLLABORATION FROM SURROUNDING OFFICES
AND NAM/GFS MOMENTUM TRANSFER VALUES NOT BEING QUITE AS HIGH AS HI
RES GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
400 AM UPDATE...
EAST/WEST BOUNDARY MENTIONED ABOVE SLOWLY MOVES NORTH TONIGHT. THE
DYNAMICS ARE BEST EARLY IN THE NIGHT BUT GRADUALLY FADE AS
PRECIPITATION SHIELD LIFTS NORTH LATE. UP TO ANOTHER INCH OR SO OF
SNOW IS POSSIBLE AGAIN TONIGHT, BUT THE AXIS WILL BE SLIGHTLY
SHIFTED A FEW COUNTIES NORTH. WHILE SHOWERS CAN`T BE RULED OUT
MOST OF MONDAY INTO MONDAY NIGHT ACROSS CENTRAL NY, MOST OF THIS
PERIOD WILL EXPERIENCE MANY STRETCHES OF DRY WEATHER. AT THE SAME
TIME TEMPS GRADUALLY WARM UP SO ASIDE FROM SOME WET SNOW ACROSS
NORTHERN ONEIDA COUNTY MONDAY EVENING, P-TYPE CONCERNS ARE MUCH
LESS. TEMPS WILL VARY WIDELY OVER OUR AREA WITH 60S IN NEPA, BUT
ONLY IN THE 40S ACROSS NORTHERN ONEIDA COUNTY.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
445 AM UPDATE...
BUSY WET PATTERN CONTINUES. SURFACE BOUNDARY WILL SAG SOUTHWARD
TUESDAY THROUGH WEDNESDAY WITH PASSING WAVES ALOFT...FOLLOWED BY
WARM AIR ADVECTION THURSDAY-FRIDAY COURTESY OF MOIST SOUTHWEST FLOW
IN THE UPPER LEVELS. ALMOST EXCLUSIVELY RAIN FOR PRECIP
TYPE...WITH THE LITTLE BIT OF MIXED SNOW CHANCES MAINLY RELEGATED
TO HIGHER ELEVATIONS OF CENTRAL NY EARLIER IN THE PERIOD. GRIDS
ADJUSTED TOWARDS LATEST WPC GUIDANCE AND/OR MODEL TRENDS. WETTEST
DAYS APPEAR TO BE TUE-TUE NIGHT WITH AREAL AVERAGE OF ROUGHLY ONE
TO TWO THIRDS OF AN INCH...AND FRI-FRI NIGHT AS A COLD FRONT DRAPES
THROUGH WITH A MOIST ATMOSPHERE /PWATS IN EXCESS OF AN INCH IN GFS/.
PREVIOUS DISCUSSION...
CLOSELY FOLLOWED WPC GUIDANCE. EXTENDED BRINGS TRUTH TO THE
MEANING... APRIL SHOWERS... BRING MAY FLOWERS. THE EXTENDED LOOKS
VERY ACTIVE AND WET. MULTIPLE WAVES ARE EXPECTED TO PASS OVER THE
REGION DURING THE EXTENDED PERIOD BRINGING THE CHANCE FOR SHOWERS.
CONFIDENCE INCREASES ON ANOTHER STORM SYSTEM IMPACTING THE REGION
TUES NIGHT INTO WED. OVERALL... TRENDS APPEAR TO BE RAIN DURING
THE AFTERNOON AND RAIN/SNOW MIX DURING THE OVERNIGHT. THE CHANCE
FOR SHOWERS WILL EXIST EACH DAY. AT LEAST ON THE UPSIDE... TEMPS
DURING THE EXTENDED ARE EXPECTED TO REMAIN AT THE SEASONAL NORM...
AND A POSSIBLE WARMING TREND MAY OCCUR NEXT WEEKEND.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
12Z UPDATE...
VIGOROUS SHORTWAVE EARLIER IN THE NIGHT BROUGHT A QUICK SHOT OF
SNOW FOR KITH-KBGM-KELM...BUT IS NOW GONE. HOWEVER...ATTENTION
ALREADY TURNS TO NEXT INBOUND WAVE WHICH WILL OVERSPREAD THE AREA
THIS MORNING...WITH RESTRICTIONS CONTINUING THIS AFTERNOON-
EVENING. NARROW CORRIDOR OF HIGHER IMPACT SNOW MOST PROBABLE FOR
KITH-KELM-KBGM...THOUGH IN TIME MIXING WITH RAIN ESPECIALLY KELM.
KSYR-KRME ON NORTHERN EDGE OF PRECIP...ONLY HIGHER END MVFR CIG
AND VIS FIGURED FOR NOW BUT THIS WILL NEED TO BE WATCHED
CLOSELY...IF PRECIP BAND SHIFTS JUST A LITTLE NORTHWARD THEN IFR
RESTRICTIONS COULD RESULT. MEANWHILE...NOT EXPECTING ANY
RESTRICTIONS FOR KAVP...THOUGH SCT -SHRA WILL PROBABLY SKIM
THROUGH EARLY-MID AFTERNOON. WINDS MAINLY WESTERLY 10 KTS OR
LESS...BECOMING VARIABLE LATE AFTERNOON-EVENING...EXCEPT SOUTH OF
THE FRONTAL BOUNDARY KAVP WILL HAVE WSW-W WINDS 10-15 KTS WITH
GUSTS 25-30 KTS THIS AFTERNOON.
.OUTLOOK...
LATE SUN NIGHT-THURS...BUSY PATTERN WITH INTERMITTENT
RESTRICTIONS FROM -SHRA AS MULTIPLE WAVES MOVE THROUGH THE REGION.
COULD BE MIXED WITH -SHSN AT TIMES MAINLY KSYR-KRME.
&&
.HYDROLOGY...
445 AM UPDATE...
HYDROLOGY IMPACTS OF SNOWMELT AND RECENT RAIN...ARE NOW GENERALLY IN
THEIR WANING STAGES. FOR THE SUSQUEHANNA...VESTAL IS JUST SLIPPING
BELOW FLOOD STAGE...AND CONKLIN NOT FAR FROM DOING SO AS WELL. WE
WILL BE ABLE TO CANCEL ASSOCIATED FLOOD WARNINGS SHORTLY.
TIOUGHNIOGA HAS CRESTED AT CORTLAND AND IS ON ITS WAY DOWN...BUT
STILL ABOUT 0.8 FEET ABOVE FLOOD STAGE SO THAT FLOOD WARNING
CONTINUES FOR NOW...IT IS ANTICIPATED TO GET BELOW FLOOD STAGE
AROUND LATE MORNING. SEVERAL OTHER POINTS IN TIOGHNIOGA- CHENANGO-
UNADILLA- UPPER SUSQUEHANNA RIVERS...AND WALTON OF WEST BRANCH
UPPER DELAWARE...ARE ABOVE ACTION STAGE YET BELOW FLOOD
STAGE...AND ARE NOW FALLING HAVING CRESTED EARLIER.
MEANWHILE...THE SUSQUEHANNA IN TOWANDA-MESHOPPEN AREAS IS NOW IN
CRESTING /BELOW ACTION STAGE/...WHILE WILKES-BARRE IS EXPECTED TO
DO SO LATER TODAY AROUND 16.5 FEET /ABOUT HALFWAY BETWEEN ACTION
STAGE AND FLOOD STAGE/.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN
SHORT TERM...HEDEN
LONG TERM...MDP
AVIATION...MDP
HYDROLOGY...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
458 AM EDT SUN APR 5 2015
.SYNOPSIS...
SNOW WILL OVERSPREAD SOUTHERN NEW YORK AND NORTHERN PENNSYLVANIA
THIS MORNING. BY AFTERNOON THE SNOW WILL CHANGE OVER TO MOSTLY
RAIN IN LOWER ELEVATIONS, BUT SNOW MAY LINGER ON THE HILLTOPS. MONDAY
WILL BE MAINLY DRY BEFORE ANOTHER SYSTEM BRINGS LIGHT RAIN ON
TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
400 AM UPDATE...
AN INTERESTING FORECAST ACROSS OUR AREA TODAY WITH BOTH WIND AND
SNOW CONCERNS.
AN AREA OF MOISTURE NOW ALONG AN EAST/WEST FRONTAL BOUNDARY OVER THE GREAT
LAKES WILL MOVE EAST-SOUTHEAST THIS MORNING. WITH AN INTENSE TEMPERATURE
ALREADY PRESENT (20S NORTHERN LOWER MICHIGAN, 40S SOUTHERN LOWER
MICHIGAN) AND COOLING CLOUD TOPS, ALL SIGNS POINT TO A NARROW BUT
INTENSE AREA OF HEAVIER PRECIPITATION IN OUR AREA BY LATE MORNING.
IN ADDITION WITH THE ORIENTATION OF THE FRONT BEING WEST TO EAST,
OUR PRECIPITATION WILL LIKELY BE FOCUSED IN THE SAME AREA FOR A
LONG PERIOD OF TIME. FOLKS REMOVED FROM THIS BOUNDARY WELL TO OUR
NORTH AND SOUTH MAY SAY WHATS THE WORRY? IN THE MIDDLE HOWEVER,
COOL TEMPS ALOFT WITH STRONG LIFT WILL BE ENOUGH TO OVERCOME A
STRONG EARLY APRIL SUN TO PRODUCE HEAVY SNOWFALL RATES EARLY
TODAY. BUFKIT PROFILES SHOW GOOD RH AND LIFT INTO THE DENDRITIC
LAYER, SHOWING THIS POTENTIAL FOR A HEAVIER BURST OF SNOW. FURTHER
SUPPORTING THE NOTION THAT THIS BAND WILL NOT BE VERY WIDE NORTH
SOUTH, BUT INSTEAD VERY ELONGATED, IS THE DIFFERENCES IN OMEGA
VALUES FROM FORECAST POINT TO FORECAST POINT. I WENT WITH MOSTLY
ALL SNOW THROUGH MIDDAY FROM NEAR THE NY/PA LINE NORTH, WITH 850S
BELOW 0C AND STRONG LIFT HELPING TO COOL THE COLUMN. BY AFTERNOON
BOUNDARY LAYER TEMPS WILL WARM ENOUGH FOR A TRANSITION TO RAIN
FIRST IN THE VALLEYS AND EVENTUALLY LATER OVER THE HILLS. STILL
CONCERNED A FEW OF THE HIGHER ELEVATIONS MAY HAVE TROUBLE
SWITCHING OVER TO RAIN, GIVEN SUCH STRONG LIFT IN THE COLUMN. ITS
VERY POSSIBLE WE MAY HAVE MODERATE SNOWFALL RATES EVEN WITH
SURFACE TEMPS IN THE 34-36 RANGE. I WENT A COATING TO 2 INCHES BY
AFTERNOON ACROSS THE FINGER LAKES, SOUTHERN TIER, AND EXTREME
NORTHERN TIER OF PA. A FEW 3 INCH VALUES ARE POSSIBLE ESPECIALLY
OVER THE HIGHER TERRAIN WHERE THE TRANSITION TO RAIN WILL TAKE
LONGER. WHILE MOST OF THE ACCUMULATION WILL OCCUR TO GRASSY
SURFACES WITH MAINLY JUST WET ROADS, SOME SLUSHY SPOTS CAN`T BE
RULED OUT DURING THE HEAVIER PERIODS OF SNOW. AGAIN MOST LIKELY
HIGHER TERRAIN/SHADY SPOTS, ELEVATED BRIDGES, ETC. HIGHLIGHTED
THIS IN OUR HWO.
FARTHER SOUTH TOWARD THE WYOMING VALLEY AND THE POCONOS MOST OF
THE DAY MAY REMAIN DRY BUT VERY WINDY. HRRR WIND GUSTS, WHICH DID
VERY WELL YESTERDAY, SHOW GUSTS OVER 30 MPH THROUGH AFTERNOON. RAP
VALUES ARE ALSO SIMILAR. I INCREASED WIND SPEEDS HERE AND
MENTIONED THIS IN THE HWO. WOULD NOT RULE OUT A FEW POWER OUTAGES
IN THIS AREA WITH AN INVERTED V SOUNDING AND STEEP LAPSE RATES TO
600 MB SCREAMING WIND POTENTIAL. WILL PASS ONTO THE DAY SHIFT THIS
POTENTIAL IN CASE A SHORT TERM WIND ADVISORY IS NEEDED. FOR NOW
HELD OFF ON ANYTHING WITH COLLABORATION FROM SURROUNDING OFFICES
AND NAM/GFS MOMENTUM TRANSFER VALUES NOT BEING QUITE AS HIGH AS HI
RES GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
400 AM UPDATE...
EAST/WEST BOUNDARY MENTIONED ABOVE SLOWLY MOVES NORTH TONIGHT. THE
DYNAMICS ARE BEST EARLY IN THE NIGHT BUT GRADUALLY FADE AS
PRECIPITATION SHIELD LIFTS NORTH LATE. UP TO ANOTHER INCH OR SO OF
SNOW IS POSSIBLE AGAIN TONIGHT, BUT THE AXIS WILL BE SLIGHTLY
SHIFTED A FEW COUNTIES NORTH. WHILE SHOWERS CAN`T BE RULED OUT
MOST OF MONDAY INTO MONDAY NIGHT ACROSS CENTRAL NY, MOST OF THIS
PERIOD WILL EXPERIENCE MANY STRETCHES OF DRY WEATHER. AT THE SAME
TIME TEMPS GRADUALLY WARM UP SO ASIDE FROM SOME WET SNOW ACROSS
NORTHERN ONEIDA COUNTY MONDAY EVENING, P-TYPE CONCERNS ARE MUCH
LESS. TEMPS WILL VARY WIDELY OVER OUR AREA WITH 60S IN NEPA, BUT
ONLY IN THE 40S ACROSS NORTHERN ONEIDA COUNTY.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
445 AM UPDATE...
BUSY WET PATTERN CONTINUES. SURFACE BOUNDARY WILL SAG SOUTHWARD
TUESDAY THROUGH WEDNESDAY WITH PASSING WAVES ALOFT...FOLLOWED BY
WARM AIR ADVECTION THURSDAY-FRIDAY COURTESY OF MOIST SOUTHWEST FLOW
IN THE UPPER LEVELS. ALMOST EXCLUSIVELY RAIN FOR PRECIP
TYPE...WITH THE LITTLE BIT OF MIXED SNOW CHANCES MAINLY RELEGATED
TO HIGHER ELEVATIONS OF CENTRAL NY EARLIER IN THE PERIOD. GRIDS
ADJUSTED TOWARDS LATEST WPC GUIDANCE AND/OR MODEL TRENDS. WETTEST
DAYS APPEAR TO BE TUE-TUE NIGHT WITH AREAL AVERAGE OF ROUGHLY ONE
TO TWO THIRDS OF AN INCH...AND FRI-FRI NIGHT AS A COLD FRONT DRAPES
THROUGH WITH A MOIST ATMOSPHERE /PWATS IN EXCESS OF AN INCH IN GFS/.
PREVIOUS DISCUSSION...
CLOSELY FOLLOWED WPC GUIDANCE. EXTENDED BRINGS TRUTH TO THE
MEANING... APRIL SHOWERS... BRING MAY FLOWERS. THE EXTENDED LOOKS
VERY ACTIVE AND WET. MULTIPLE WAVES ARE EXPECTED TO PASS OVER THE
REGION DURING THE EXTENDED PERIOD BRINGING THE CHANCE FOR SHOWERS.
CONFIDENCE INCREASES ON ANOTHER STORM SYSTEM IMPACTING THE REGION
TUES NIGHT INTO WED. OVERALL... TRENDS APPEAR TO BE RAIN DURING
THE AFTERNOON AND RAIN/SNOW MIX DURING THE OVERNIGHT. THE CHANCE
FOR SHOWERS WILL EXIST EACH DAY. AT LEAST ON THE UPSIDE... TEMPS
DURING THE EXTENDED ARE EXPECTED TO REMAIN AT THE SEASONAL NORM...
AND A POSSIBLE WARMING TREND MAY OCCUR NEXT WEEKEND.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
06Z UPDATE...
VIGOROUS SHORTWAVE WITH BURST OF SNOW SHOWERS NOW EXITING THE
TERMINALS JUST PRIOR TO 06Z...THOUGH FUEL ALT CIG WILL LINGER
BRIEFLY FOR KBGM-KITH. OTHERWISE...ATTENTION TURNS TO NEXT WAVE
WHICH WILL OVERSPREAD THE AREA LATE MORNING...WITH RESTRICTIONS
CONTINUING THROUGH THE AFTERNOON. NARROW CORRIDOR OF HIGHER IMPACT
SNOW MOST PROBABLE FOR KITH-KELM-KBGM...THOUGH IN TIME MIXING WITH
RAIN ESPECIALLY KELM. KSYR-KRME ON NORTHERN EDGE OF PRECIP...ONLY
HIGHER END MVFR CIG AND VIS FIGURED FOR NOW BUT THIS WILL NEED TO
BE WATCHED CLOSELY...IF PRECIP BAND SHIFTS JUST A LITTLE NORTHWARD
THEN IFR RESTRICTIONS COULD RESULT. MEANWHILE...NOT EXPECTING ANY
RESTRICTIONS FOR KAVP...THOUGH SCT -SHRA WILL PROBABLY SKIM
THROUGH EARLY-MID AFTERNOON. WINDS MAINLY WESTERLY 10 KTS OR
LESS /GUSTS 15-20 KTS KAVP THIS AFTERNOON/...BECOMING VARIABLE LATE
AFTERNOON-EVENING.
.OUTLOOK...
LATE SUN NIGHT-THURS...BUSY PATTERN WITH INTERMITTENT
RESTRICTIONS FROM -SHRA AS MULTIPLE WAVES MOVE THROUGH THE REGION.
COULD BE MIXED WITH -SHSN AT TIMES MAINLY KSYR-KRME.
&&
.HYDROLOGY...
445 AM UPDATE...
HYDROLOGY IMPACTS OF SNOWMELT AND RECENT RAIN...IS NOW GENERALLY IN
THEIR WANING STAGES. FOR THE SUSQUEHANNA...VESTAL IS JUST SLIPPING
BELOW FLOOD STAGE...AND CONKLIN NOT FAR FROM DOING SO AS WELL. WE
WILL BE ABLE TO CANCEL ASSOCIATED FLOOD WARNINGS SHORTLY.
TIOUGHNIOGA HAS CRESTED AT CORTLAND AND IS ON ITS WAY DOWN...BUT
STILL ABOUT 0.8 FEET ABOVE FLOOD STAGE SO THAT FLOOD WARNING
CONTINUES FOR NOW...IT IS ANTICIPATED TO GET BELOW FLOOD STAGE
AROUND LATE MORNING. SEVERAL OTHER POINTS IN TIOGHNIOGA- CHENANGO-
UNADILLA- UPPER SUSQUEHANNA RIVERS...AND WALTON OF WEST BRANCH
UPPER DELAWARE...ARE ABOVE ACTION STAGE YET BELOW FLOOD
STAGE...AND ARE NOW FALLING HAVING CRESTED EARLIER.
MEANWHILE...THE SUSQUEHANNA IN TOWANDA-MESHOPPEN AREAS IS NOW IN
CRESTING /BELOW ACTION STAGE/...WHILE WILKES-BARRE IS EXPECTED TO
DO SO LATER TODAY AROUND 16.5 FEET /ABOUT HALFWAY BETWEEN ACTION
STAGE AND FLOOD STAGE/.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN
SHORT TERM...HEDEN
LONG TERM...MDP
AVIATION...MDP
HYDROLOGY...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
430 AM EDT SUN APR 5 2015
.SYNOPSIS...
SNOW WILL OVERSPREAD SOUTHERN NEW YORK AND NORTHERN PENNSYLVANIA
THIS MORNING. BY AFTERNOON THE SNOW WILL CHANGE OVER TO MOSTLY
RAIN IN LOWER ELEVATIONS, BUT SNOW MAY LINGER ON THE HILLTOPS. MONDAY
WILL BE MAINLY DRY BEFORE ANOTHER SYSTEM BRINGS LIGHT RAIN ON
TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
400 AM UPDATE...
AN INTERESTING FORECAST ACROSS OUR AREA TODAY WITH BOTH WIND AND
SNOW CONCERNS.
AN AREA OF MOISTURE NOW ALONG AN EAST/WEST FRONTAL BOUNDARY OVER THE GREAT
LAKES WILL MOVE EAST-SOUTHEAST THIS MORNING. WITH AN INTENSE TEMPERATURE
ALREADY PRESENT (20S NORTHERN LOWER MICHIGAN, 40S SOUTHERN LOWER
MICHIGAN) AND COOLING CLOUD TOPS, ALL SIGNS POINT TO A NARROW BUT
INTENSE AREA OF HEAVIER PRECIPITATION IN OUR AREA BY LATE MORNING.
IN ADDITION WITH THE ORIENTATION OF THE FRONT BEING WEST TO EAST,
OUR PRECIPITATION WILL LIKELY BE FOCUSED IN THE SAME AREA FOR A
LONG PERIOD OF TIME. FOLKS REMOVED FROM THIS BOUNDARY WELL TO OUR
NORTH AND SOUTH MAY SAY WHATS THE WORRY? IN THE MIDDLE HOWEVER,
COOL TEMPS ALOFT WITH STRONG LIFT WILL BE ENOUGH TO OVERCOME A
STRONG EARLY APRIL SUN TO PRODUCE HEAVY SNOWFALL RATES EARLY
TODAY. BUFKIT PROFILES SHOW GOOD RH AND LIFT INTO THE DENDRITIC
LAYER, SHOWING THIS POTENTIAL FOR A HEAVIER BURST OF SNOW. FURTHER
SUPPORTING THE NOTION THAT THIS BAND WILL NOT BE VERY WIDE NORTH
SOUTH, BUT INSTEAD VERY ELONGATED, IS THE DIFFERENCES IN OMEGA
VALUES FROM FORECAST POINT TO FORECAST POINT. I WENT WITH MOSTLY
ALL SNOW THROUGH MIDDAY FROM NEAR THE NY/PA LINE NORTH, WITH 850S
BELOW 0C AND STRONG LIFT HELPING TO COOL THE COLUMN. BY AFTERNOON
BOUNDARY LAYER TEMPS WILL WARM ENOUGH FOR A TRANSITION TO RAIN
FIRST IN THE VALLEYS AND EVENTUALLY LATER OVER THE HILLS. STILL
CONCERNED A FEW OF THE HIGHER ELEVATIONS MAY HAVE TROUBLE
SWITCHING OVER TO RAIN, GIVEN SUCH STRONG LIFT IN THE COLUMN. ITS
VERY POSSIBLE WE MAY HAVE MODERATE SNOWFALL RATES EVEN WITH
SURFACE TEMPS IN THE 34-36 RANGE. I WENT A COATING TO 2 INCHES BY
AFTERNOON ACROSS THE FINGER LAKES, SOUTHERN TIER, AND EXTREME
NORTHERN TIER OF PA. A FEW 3 INCH VALUES ARE POSSIBLE ESPECIALLY
OVER THE HIGHER TERRAIN WHERE THE TRANSITION TO RAIN WILL TAKE
LONGER. WHILE MOST OF THE ACCUMULATION WILL OCCUR TO GRASSY
SURFACES WITH MAINLY JUST WET ROADS, SOME SLUSHY SPOTS CAN`T BE
RULED OUT DURING THE HEAVIER PERIODS OF SNOW. AGAIN MOST LIKELY
HIGHER TERRAIN/SHADY SPOTS, ELEVATED BRIDGES, ETC. HIGHLIGHTED
THIS IN OUR HWO.
FARTHER SOUTH TOWARD THE WYOMING VALLEY AND THE POCONOS MOST OF
THE DAY MAY REMAIN DRY BUT VERY WINDY. HRRR WIND GUSTS, WHICH DID
VERY WELL YESTERDAY, SHOW GUSTS OVER 30 MPH THROUGH AFTERNOON. RAP
VALUES ARE ALSO SIMILAR. I INCREASED WIND SPEEDS HERE AND
MENTIONED THIS IN THE HWO. WOULD NOT RULE OUT A FEW POWER OUTAGES
IN THIS AREA WITH AN INVERTED V SOUNDING AND STEEP LAPSE RATES TO
600 MB SCREAMING WIND POTENTIAL. WILL PASS ONTO THE DAY SHIFT THIS
POTENTIAL IN CASE A SHORT TERM WIND ADVISORY IS NEEDED. FOR NOW
HELD OFF ON ANYTHING WITH COLLABORATION FROM SURROUNDING OFFICES
AND NAM/GFS MOMENTUM TRANSFER VALUES NOT BEING QUITE AS HIGH AS HI
RES GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
400 AM UPDATE...
EAST/WEST BOUNDARY MENTIONED ABOVE SLOWLY MOVES NORTH TONIGHT. THE
DYNAMICS ARE BEST EARLY IN THE NIGHT BUT GRADUALLY FADE AS
PRECIPITATION SHIELD LIFTS NORTH LATE. UP TO ANOTHER INCH OR SO OF
SNOW IS POSSIBLE AGAIN TONIGHT, BUT THE AXIS WILL BE SLIGHTLY
SHIFTED A FEW COUNTIES NORTH. WHILE SHOWERS CAN`T BE RULED OUT
MOST OF MONDAY INTO MONDAY NIGHT ACROSS CENTRAL NY, MOST OF THIS
PERIOD WILL EXPERIENCE MANY STRETCHES OF DRY WEATHER. AT THE SAME
TIME TEMPS GRADUALLY WARM UP SO ASIDE FROM SOME WET SNOW ACROSS
NORTHERN ONEIDA COUNTY MONDAY EVENING, P-TYPE CONCERNS ARE MUCH
LESS. TEMPS WILL VARY WIDELY OVER OUR AREA WITH 60S IN NEPA, BUT
ONLY IN THE 40S ACROSS NORTHERN ONEIDA COUNTY.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
CLOSELY FOLLOWED WPC GUIDANCE...
EXTENDED BRINGS TRUTH TO THE MEANING... APRIL SHOWERS... BRING MAY
FLOWERS. THE EXTENDED LOOKS VERY ACTIVE AND WET. MULTP WAVES ARE
EXPECTED TO PASS OVER THE RGION DURING THE EXTENDED PERIOD BRINGING
THE CHANCE FOR SHOWERS. CONFIDENCE INCREASES ON ANOTHER STORM
SYSTEM IMPACTING THE REGION TUES NIGHT INTO WED. OVERALL... TRENDS
APPEAR TO BE RAIN DURING THE AFTERNOON AND RAIN/SNOW MIX DURING
THE OVERNIGHT. THE CHANCE FOR SHOWERS WILL EXIST EACH DAY. AT
LEAST ON THE UPSIDE... TEMPS DURING THE EXTENDED ARE EXPECTED TO
REMAIN AT THE SEASONAL NORM... AND A POSSIBLE WARMING TREND MAY
OCCUR NEXT WEEKEND.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
06Z UPDATE...
VIGOROUS SHORTWAVE WITH BURST OF SNOW SHOWERS NOW EXITING THE
TERMINALS JUST PRIOR TO 06Z...THOUGH FUEL ALT CIG WILL LINGER
BRIEFLY FOR KBGM-KITH. OTHERWISE...ATTENTION TURNS TO NEXT WAVE
WHICH WILL OVERSPREAD THE AREA LATE MORNING...WITH RESTRICTIONS
CONTINUING THROUGH THE AFTERNOON. NARROW CORRIDOR OF HIGHER IMPACT
SNOW MOST PROBABLE FOR KITH-KELM-KBGM...THOUGH IN TIME MIXING WITH
RAIN ESPECIALLY KELM. KSYR-KRME ON NORTHERN EDGE OF PRECIP...ONLY
HIGHER END MVFR CIG AND VIS FIGURED FOR NOW BUT THIS WILL NEED TO
BE WATCHED CLOSELY...IF PRECIP BAND SHIFTS JUST A LITTLE NORTHWARD
THEN IFR RESTRICTIONS COULD RESULT. MEANWHILE...NOT EXPECTING ANY
RESTRICTIONS FOR KAVP...THOUGH SCT -SHRA WILL PROBABLY SKIM
THROUGH EARLY-MID AFTERNOON. WINDS MAINLY WESTERLY 10 KTS OR
LESS /GUSTS 15-20 KTS KAVP THIS AFTERNOON/...BECOMING VARIABLE LATE
AFTERNOON-EVENING.
.OUTLOOK...
LATE SUN NIGHT-THURS...BUSY PATTERN WITH INTERMITTENT
RESTRICTIONS FROM -SHRA AS MULTIPLE WAVES MOVE THROUGH THE REGION.
COULD BE MIXED WITH -SHSN AT TIMES MAINLY KSYR-KRME.
&&
.HYDROLOGY...
10 AM UPDATE...
RIVER FLOOD WARNINGS FOR THE SUSQUEHANNA RIVER AT CONKLIN AND
VESTAL. CRESTS THIS EVENING AND BACK BELOW FS SUNDAY MORNING. REST
OF POINTS SHOULD STAY BELOW FLOOD STAGE.
445 AM UPDATE...
RIVERS AND STREAMS WILL CONTINUE TO RISE SEVERAL FEET THIS WEEKEND
IN RESPONSE TO SIGNIFICANT SNOWMELT RUNOFF AND THE QUARTER TO HALF
INCH OF RAINFALL FROM THE CURRENT SYSTEM THAT IS BEGINNING TO EXIT
/WITH SOME PLACES FINISHING UP WITH ANOTHER TENTH INCH OR TWO
BEFORE DAWN/. COLDER TEMPERATURES BY SUNDAY WILL RESULT IN LESS
RUNOFF AND ALLOW RIVER LEVELS TO BEGIN DROPPING EARLY NEXT WEEK.
RIVERS IN THE UPPER SUSQUEHANNA...CHENANGO...TIOUGHNIOGA AND WEST
BRANCH DELAWARE BASINS WILL BE THE MOST SENSITIVE TO THE MELTING
SNOW AND RAINFALL...WITH LEVELS FORECAST TO CREST BETWEEN 3/4
AND BANKFULL. THE TIOUGHNIOGA HAS HAD THE MOST RESPONSE SO
FAR...WITH THE ITASKA GAGE EARLIER IN THE NIGHT HAVING BRIEFLY HIT
FLOOD STAGE /NOW BELOW/...AND THE CORTLAND GAGE EXPECTED TO REACH
ITS 8.0 FOOT FLOOD STAGE AROUND 8 AM THIS MORNING...THUS A FLOOD
WARNING HAS BEEN ISSUED FOR THAT POINT BUT ONLY MINOR FLOODING IS
ANTICIPATED. THERE IS A CHANCE THAT WATER IN A FEW OTHER SPOTS
WITHIN THE BASINS MENTIOEND ABOVE...COULD REACH MINOR FLOOD STAGE
AND SPILL INTO THE NATURAL FLOOD PLAIN OUTSIDE THE RIVER BANK. NO
SIGNIFICANT FLOODING IMPACTS ARE EXPECTED IF THIS OCCURS. IN OTHER
BASINS...RIVERS SHOULD CREST BETWEEN ABOUT 1/2 TO 3/4 BANKFULL.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN
SHORT TERM...HEDEN
LONG TERM...KAH
AVIATION...MDP
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1010 PM EDT MON APR 6 2015
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE OFFSHORE THROUGH MIDWEEK. A COLD
FRONT WILL PUSH SOUTH INTO THE REGION LATE WEDNESDAY AND STALL
OVER OR SOUTH OF THE AREA THROUGH EARLY THURSDAY. THE FRONT WILL
LIFT NORTH OF THE REGION THURSDAY NIGHT AND FRIDAY. A COLD FRONT
WILL APPROACH FROM THE WEST FRIDAY NIGHT. THE FRONT WILL CROSS
EASTERN NC SATURDAY THEN STALL SOUTH OF THE AREA SUNDAY INTO
MONDAY.
&&
.NEAR TERM /OVERNIGHT/...
AS OF 1010 PM MONDAY...SURFACE RIDGE CONTINUES OFFSHORE AS FAST
ZONAL FLOW ALOFT KEEPS MID AND HIGH LEVEL CLOUDS STREAMING EAST
ACROSS THE REGION. CURRENT FORECAST IN GOOD SHAPE JUST SOME
MINOR ADJUSTMENTS IN WINDS OVERNIGHT. MODEL GUIDANCE CONTINUES TO
BACK OFF ON ANY PRECIP CHANCES OVERNIGHT GIVEN THE LACK OF FORCING
MECHANISMS SO HAVE REMOVED ALL POPS, ALTHO CUD SEE SOME VERY LIGHT
PRECIP DEEP INLAND TOWARD SUNRISE THROUGH THE MORNING WELL AHEAD
SHORT WAVE ENERGY. A MILD NIGHT IS FORECAST WITH INCREASING CLOUDS
AND SOUTHERLY SFC FLOW. LOWS MAINLY IN THE MID/UPPER 50S INLAND TO
AROUND 60 AT THE BEACHES.
&&
.SHORT TERM /TUESDAY/...
MINOR SHORT WAVE IN THE FLAT ZONAL FLOW ALOFT AND INCREASING LOW
LEVEL MOISTURE WILL BRING PRECIP CHANCES AT JUST ABOUT ANYTIME
TUESDAY. HOWEVER MODEL TRENDS CONTINUE TO BE DRIER AND WILL CAP
POPS AT HIGH CHANCE FOR NOW. HAVE HELD ONTO ISOLATED TSTM CHANCES
FOR THE AFTERNOON BUT INSTABILITY AND AVAILABLE SHEAR WILL BE WEAK
SO STRONG/SEVERE STORMS NOT ANTICIPATED. THIS ALSO APPEARS TO BE A
LOW QPF EVENT GIVEN THE WEAK FORCING WITH MOST RAINFALL AMOUNTS
EXPECTED TO BE .25" OR LESS. DESPITE CONSIDERABLE CLOUDINESS,
LOCAL THICKNESS SCHEME SUPPORTS HIGHS IN THE MID TO POSSIBLY UPPER
70S INLAND WITH 65 TO 70 DEGREES AT THE BEACHES.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
AS OF 345 PM MON...A WEAK SURFACE LOW COUPLED WITH AN UPPER LEVEL
DISTURBANCE WILL SHIFT EAST ALONG THE NC/VA BORDER TUESDAY NIGHT.
TRENDED POPS/WX/QPF BASED ON GENERAL MODEL BLEND, WHICH HAS SHOWN
SOME BETTER AGREEMENT WITH 12Z GUIDANCE. MOISTURE WILL GRADUALLY
SLIDE OFFSHORE LATE TUES NIGHT AND KEPT CHANCE POPS WITH SLIGHT
CHANCE THUNDER THROUGH MIDNIGHT, THEN SLIGHT CHANCE INLAND WITH
MILD TEMPERATURES, LOWS MAINLY IN LOWER 60S.
WED THROUGH THURS...MODELS CONTINUE TO INDICATE A WEAK BACKDOOR
FRONT DROPPING SOUTH INTO AREA LATE WED INTO WED NIGHT. NAM/SREF/GFS
MOST AGGRESSIVE WITH FRONT SHIFTING WELL SOUTH WED NIGHT WHILE
THE ECMWF/GEM HANG UP THE FRONT OVER EASTERN NC OR JUST NORTH OF
THE CWA BORDER. WILL BE WARM AHEAD OF FRONT WED WITH LOWER 80S
INLAND. KEPT CHANCE POPS INLAND AND NORTH WED CLOSER TO FRONT AND
DEEPER MOISTURE WITH SLIGHT CHANCE SOUTHERN BEACHES. WITH MOST
GUIDANCE INDICATING THE FRONT SHIFTS SOUTH OF THE CWA WED NIGHT,
CARRIED ONLY SLIGHT CHANCE POPS FOR THE AREA WED NIGHT, THEN
CHANCE INLAND TO SLIGHT CHANCE ALONG THE COAST THURSDAY. HIGHS
THURS WILL VARY SIGNIFICANTLY WITH NORTHERN BEACHES AROUND 60 AND
SOUTHERN AREAS AROUND 80.
FRI THROUGH MONDAY...FRONT WILL LIFT NORTH OF REGION FRI WITH
LIMITED CHANCE OF PRECIP AND WARM TEMPS IN THE LOWER 80S INLAND.
ANOTHER FRONT WILL APPROACH FROM THE WEST FRIDAY NIGHT THAT WILL
CROSS EASTERN NC ON SATURDAY AND EVENTUALLY SHIFT SOUTH OF THE
REGION SATURDAY EVENING/NIGHT AS HIGH PRESSURE OVER THE MID-
ATLANTIC STATES BUILDS SOUTH OVER EASTERN NC SUNDAY AND MONDAY.
WILL KEEP CHC POPS OVER AREA SAT BUT HAVE REMOVED POPS SUNDAY AND
MONDAY DUE TO DECENT AGREEMENT AMONGST LONG RANGE GUIDANCE.
CONTINUED MILD WITH TEMPS INLAND WELL INTO THE 70S SATURDAY
THROUGH MONDAY.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH 00Z WEDNESDAY/...
AS OF 7 PM MONDAY...WITH WIDESPREAD MID AND HIGH-LEVEL
CLOUDINESS...VFR CONDITIONS SHOULD PREVAIL INTO THE EARLY MORNING
HOURS AS LOWER CLOUDS GRADUALLY DIMINISH WITH LOSS OF HEATING.
MODEL TIME SECTIONS AND MOS GUIDANCE STILL SUPPORT A PERIOD OF
MVFR CEILINGS TO DEVELOP AS LOW LEVEL MOISTURE TRAPS UNDER
NOCTURNAL INVERSION LATE TONIGHT. THE LOWER CLOUD BASES WILL MIX
OUT BY AROUND MID MORNING WITH MAINLY VFR EXPECTED THEREAFTER.
LATEST MODEL RUNS STILL SUGGEST THAT MUCH OF THE PRECIP MOVING IN
AHEAD OF SHORT WAVE ENERGY WILL FALL LATER TUESDAY NIGHT AND ANY
PRECIPITATION THAT FALLS DURING THE DAY WILL BE QUITE LIGHT.
LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 4 PM MON...DECENT COVERAGE OF SHRA AND A FEW TSRA INTO
TUESDAY EVENING WITH PERIODS OF SUB-VFR LIKELY. PRECIP WILL
DIMINISH LATE TUE NIGHT AND FIRST PART OF WED WITH MAINLY VFR,
LOW LEVELS MOIST SO CANT RULE OUT SOME SUB-VFR CIGS AT TIMES.
BACKDOOR FRONT WILL SAG SOUTH INTO THE REGION LATE WED INTO WED
NIGHT. SCATTERED SHOWERS AND A FEW STORMS POSSIBLE WED AFTERNOON
THROUGH THURS WITH AGAIN SOME PERIODS OF SUB-VFR EXPECTED. FRONT
WILL LIFT NORTH OF THE REGION FRI WITH LIMITED CHANCES OF SHRA
AND MAINLY VFR. ANOTHER COLD FRONT WILL CROSS THE REGION SATURDAY
WITH LOWERED CEILINGS/VSBYS POSSIBLE IN SHOWERS/THUNDERSTORMS
AHEAD OF/ASSOCIATED WITH FRONTAL PASSAGE.
&&
.MARINE...
SHORT TERM /THROUGH TUESDAY/...
AS OF 1010 PM MONDAY...NO MAJOR CHANGES, WITH JUST MINOR
ADJUSTMENTS TO SHORT TERM WINDS WITH HRRR MODEL INITIALIZING WELL
AND HAVE POPULATED WINDS WITH HRRR THROUGH THE OVERNIGHT. WINDS
ARE SE/S AT 15 KNOTS OR LESS WITH SEAS GENERALLY 2 TO 3 FEET.
WINDS WILL DIMINISH A BIT LATER TONIGHT. SPEEDS WILL THEN INCREASE
FURTHER TO AROUND 15 KT TUESDAY AFTERNOON WITH 2 TO 3 FT SEAS
TONIGHT BUILDING TO 3 TO 4 FT BY TUESDAY AFTERNOON.
LONG TERM /TUES NIGHT THROUGH SATURDAY/...
AS OF 410 PM MON...WEAK SURFACE LOW WILL TRACK EAST OFF THE NC/VA
COAST TUES NIGHT WITH A BACKDOOR COLD FRONT SLIDING SOUTH DOWN THE
COAST LATE WED INTO WED NIGHT. SEAS WILL BE 2-4 FEET TUES NIGHT
WITH SOME 5 FT SEAS OUTER CENTRAL WATERS. WINDS FORECAST BECOMES
TRICKY WED AFTERNOON/EVENING AS EXACT LOCATION OF BACKDOOR COLD
FRONT IS UNCERTAIN AT THIS TIME. GENERAL GUIDANCE BLEND PUSHES THE
COULD FRONT THROUGH THE EASTERN NC COASTAL WATERS LATE WED
EVENING. MAINLY SW WINDS 10 TO 15 KTS WED, BECOMING LIGHT
NORTHERN TIER AND SHIFTING NORTHERLY LATE AS FRONT SAGS INTO THE
NORTHERN WATERS, WITH SEAS 2-4 FEET. WINDS SHIFT NORTH 5-15 KT
LATE WED NIGHT AND THURS WITH SEAS 3-5 FT NORTH TO 2-4 FT SOUTH.
FRONT LIFTS BACK NORTH OF REGION LATE THURS NIGHT WITH SSW WINDS
INCREASING TO 15 TO 20 KTS FRI. SEAS WILL BUILD TO 3 TO 5 FEET
FRI...POSSIBLY REACHING 6 FT OUTER CENTRAL WATERS LATE.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...BTC
NEAR TERM...CTC/TL
SHORT TERM...BTC
LONG TERM...DAG
AVIATION...CTC/DAG
MARINE...BTC/CTC/DAG/TL
AREA FORECAST DISCUSSION
NWS BISMARCK ND
847 PM CDT MON APR 6 2015
.UPDATE...
ISSUED AT 842 PM CDT MON APR 6 2015
ISENTROPIC LIFT GENERALLY LACKING ON THE 285K SURFACE OVER
SOUTHWEST AND SOUTHERN NORTH DAKOTA THIS EVENING. MAIN ACTION
FOR SNOW CONTINUES TO BE NORTHWEST INTO THE WEST CENTRAL SECTIONS
OF NORTH DAKOTA. FOR THE REST OF THE EVENING WILL DROP POPS BELOW
15 PERCENT ACROSS THE SOUTHERN THIRD OF THE STATE. WILL THEN
SLOWLY SPREAD CHANCE POPS BACK IN AFTER MIDNIGHT SOUTH. WILL ALSO
TRIM QPF SOUTH AS WELL. THE NORTH LOOKS GOOD.
UPDATE ISSUED AT 618 PM CDT MON APR 6 2015
LATEST HRRR SEEMS TO HAVE A REASONABLE HANDLE ON THE TRENDS EARLY
THIS EVENING AND FOLLOWED FOR THE NEXT 6 HOURS OR SO. BAND OF
PRECIPITATION SEEN ON RADAR EXTENDING FROM BISMARCK NORTHWEST TO
BEACH IS MOVING NORTH AND WILL SPREAD ACROSS NORTHWEST ND WHERE
CURRENT HIGH POPS ARE IN GOOD SHAPE. THIS LEAVES THE SOUTHERN
THIRD OF THE STATE WITH LITTLE IN THE WAY OF PRECIPITATION. SO
TRIMMED THE POPS BACK TO SLIGHT CHANCE ACROSS THE SOUTH FOR THE
EVENING. FOCUSED ON THE WEST CENTRAL AND NORTHWEST WHERE BEST
PRECIPITATION WILL BE WIDESPREAD THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 300 PM CDT MON APR 6 2015
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE RAIN AND
SNOW CHANCES AND AMOUNTS NOW THROUGH TUESDAY.
CURRENTLY...THE FIRST IN A SERIES OF MID LEVEL S/WV`S APPROACHING
THE NORTHERN PLAINS THIS AFTERNOON. IN RESPONSE PRECIPITATION
DEVELOPMENT UNDERWAY SOUTHWEST WITH BEACH AND DICKINSON NOW
REPORTING SNOW THE PAST HOUR. VERY DRY AIR ACROSS EASTERN NORTH
DAKOTA WILL PREVENT ANYTHING FROM REACHING THE GROUND THIS
AFTERNOON.
PRECIPITATION WILL CONTINUE TO EXPAND NORTH AND EAST AS THE
AFOREMENTIONED WAVE CONTINUES NORTHEAST AND ONCE A STRONGER/MORE
INTENSE WAVE LIFTS INTO THE REGION TONIGHT. IN ADDITION...LOW/MID
LEVEL WINDS WILL BECOME MORE SOUTHEAST TONIGHT VERSUS
EASTERLY...ALLOWING FOR MOISTURE ADVECTION INTO THE REGION HELPING
TO ERODE A VERY DRY BOUNDARY LAYER NOW IN PLACE. SHOULD SEE A
TRANSITION TO ALL SNOW AFTER 00Z AS TEMPERATURES COOL. WILL
CONTINUE THE SPECIAL WEATHER STATEMENT HIGHLIGHTING 3 TO 5 INCHES
OF SNOW FOR PORTIONS OF THE WEST/NORTHWEST/NORTH CENTRAL DURING
THE NEXT 36 HOURS. LESSER AMOUNTS STILL EXPECTED SOUTHWEST AND
SOUTH CENTRAL WHERE A RAIN/SNOW MIX OR ALL RAIN WILL MINIMIZE
ACCUMULATIONS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 300 PM CDT MON APR 6 2015
THE FOCUS OF THE LONG TERM FORECAST IS THE CHANCE FOR RAIN/SNOW
WEDNESDAY.
LATEST 12 UTC GUIDANCE (WITH THE EXCEPTION OF THE NAM) ARE IN GOOD
AGREEMENT WITH RESPECT TO THE TIMING AND LOCATION OF PRECIPITATION
WEDNESDAY. SNOW IS EXPECTED TO MIX WITH RAIN ACROSS SOUTHWESTERN
NORTH DAKOTA WEDNESDAY MORNING AS A RATHER LARGE AND DEEP LOW
PRESSURE CENTER MOVES ACROSS THE CENTRAL PLAINS. DURING THE DAY
ON WEDNESDAY TEMPERATURES SHOULD BE WARM ENOUGH TO CHANGE SNOW
OVER TO ALL RAIN AND MELT ANY PREVIOUSLY ACCUMULATED SNOW ACROSS
SOUTHERN NORTH DAKOTA. THE MAJORITY OF THE PRECIPITATION AS
DEPICTED IN THE 12 UTC GFS/ECMWF/SREF APPEARS MOST LIKELY TO FALL
ALONG AND SOUTH OF INTERSTATE 94. AS COLDER AIR WRAPS AROUND THE
DEPARTING LOW AND DIURNAL COOLING BEGINS...RAIN MAY TRANSITION
BACK OVER TO SNOW WEDNESDAY NIGHT INTO THURSDAY MORNING.
HOWEVER...ONLY MINOR AMOUNTS ARE ANTICIPATED TO ACCUMULATE AS
GROUND TEMPERATURES SHOULD HOVER RIGHT AROUND FREEZING OVERNIGHT.
THE REST OF THE EXTENDED LOOKS RATHER DRY AND MILD WITH
TEMPERATURES IN THE 60S BY THE WEEKEND. PRECIPITATION MAY RETURN TO
THE REGION BY THE END OF THE WEEKEND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 842 PM CDT MON APR 6 2015
HIGH PRESSURE ACROSS MANITOBA WILL MOVE SOUTHEAST TONIGHT AND INITIALLY
MAINTAIN VFR CONDITIONS FROM KMOT-KBIS-KJMS. LOW PRESSURE FROM
MONTANA INTO WYOMING WILL MOVE EAST. EXPECT IFR IN LOW CLOUDS AND
SNOW AT KISN. KDIK WILL INITIALLY BE VFR...THEN GRADUALLY
DETERIORATED TO IFR AFTER 06Z. AS THE TROUGH MOVES EAST KMOT-KBIS-
KJMS WILL ALSO DETERIORATE TO IFR IN LOW CLOUDS AND SNOW AFTER
09Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...NH
LONG TERM...AJ
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
635 PM CDT MON APR 6 2015
.UPDATE...
ISSUED AT 618 PM CDT MON APR 6 2015
LATEST HRRR SEEMS TO HAVE A REASONABLE HANDLE ON THE TRENDS EARLY
THIS EVENING AND FOLLOWED FOR THE NEXT 6 HOURS OR SO. BAND OF
PRECIPITATION SEEN ON RADAR EXTENDING FROM BISMARCK NORTHWEST TO
BEACH IS MOVING NORTH AND WILL SPREAD ACROSS NORTHWEST ND WHERE
CURRENT HIGH POPS ARE IN GOOD SHAPE. THIS LEAVES THE SOUTHERN
THIRD OF THE STATE WITH LITTLE IN THE WAY OF PRECIPITATION. SO
TRIMMED THE POPS BACK TO SLIGHT CHANCE ACROSS THE SOUTH FOR THE
EVENING. FOCUSED ON THE WEST CENTRAL AND NORTHWEST WHERE BEST
PRECIPITATION WILL BE WIDESPREAD THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 300 PM CDT MON APR 6 2015
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE RAIN AND
SNOW CHANCES AND AMOUNTS NOW THROUGH TUESDAY.
CURRENTLY...THE FIRST IN A SERIES OF MID LEVEL S/WV`S APPROACHING
THE NORTHERN PLAINS THIS AFTERNOON. IN RESPONSE PRECIPITATION
DEVELOPMENT UNDERWAY SOUTHWEST WITH BEACH AND DICKINSON NOW
REPORTING SNOW THE PAST HOUR. VERY DRY AIR ACROSS EASTERN NORTH
DAKOTA WILL PREVENT ANYTHING FROM REACHING THE GROUND THIS
AFTERNOON.
PRECIPITATION WILL CONTINUE TO EXPAND NORTH AND EAST AS THE
AFOREMENTIONED WAVE CONTINUES NORTHEAST AND ONCE A STRONGER/MORE
INTENSE WAVE LIFTS INTO THE REGION TONIGHT. IN ADDITION...LOW/MID
LEVEL WINDS WILL BECOME MORE SOUTHEAST TONIGHT VERSUS
EASTERLY...ALLOWING FOR MOISTURE ADVECTION INTO THE REGION HELPING
TO ERODE A VERY DRY BOUNDARY LAYER NOW IN PLACE. SHOULD SEE A
TRANSITION TO ALL SNOW AFTER 00Z AS TEMPERATURES COOL. WILL
CONTINUE THE SPECIAL WEATHER STATEMENT HIGHLIGHTING 3 TO 5 INCHES
OF SNOW FOR PORTIONS OF THE WEST/NORTHWEST/NORTH CENTRAL DURING
THE NEXT 36 HOURS. LESSER AMOUNTS STILL EXPECTED SOUTHWEST AND
SOUTH CENTRAL WHERE A RAIN/SNOW MIX OR ALL RAIN WILL MINIMIZE
ACCUMULATIONS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 300 PM CDT MON APR 6 2015
THE FOCUS OF THE LONG TERM FORECAST IS THE CHANCE FOR RAIN/SNOW
WEDNESDAY.
LATEST 12 UTC GUIDANCE (WITH THE EXCEPTION OF THE NAM) ARE IN GOOD
AGREEMENT WITH RESPECT TO THE TIMING AND LOCATION OF PRECIPITATION
WEDNESDAY. SNOW IS EXPECTED TO MIX WITH RAIN ACROSS SOUTHWESTERN
NORTH DAKOTA WEDNESDAY MORNING AS A RATHER LARGE AND DEEP LOW
PRESSURE CENTER MOVES ACROSS THE CENTRAL PLAINS. DURING THE DAY
ON WEDNESDAY TEMPERATURES SHOULD BE WARM ENOUGH TO CHANGE SNOW
OVER TO ALL RAIN AND MELT ANY PREVIOUSLY ACCUMULATED SNOW ACROSS
SOUTHERN NORTH DAKOTA. THE MAJORITY OF THE PRECIPITATION AS
DEPICTED IN THE 12 UTC GFS/ECMWF/SREF APPEARS MOST LIKELY TO FALL
ALONG AND SOUTH OF INTERSTATE 94. AS COLDER AIR WRAPS AROUND THE
DEPARTING LOW AND DIURNAL COOLING BEGINS...RAIN MAY TRANSITION
BACK OVER TO SNOW WEDNESDAY NIGHT INTO THURSDAY MORNING.
HOWEVER...ONLY MINOR AMOUNTS ARE ANTICIPATED TO ACCUMULATE AS
GROUND TEMPERATURES SHOULD HOVER RIGHT AROUND FREEZING OVERNIGHT.
THE REST OF THE EXTENDED LOOKS RATHER DRY AND MILD WITH
TEMPERATURES IN THE 60S BY THE WEEKEND. PRECIPITATION MAY RETURN TO
THE REGION BY THE END OF THE WEEKEND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 618 PM CDT MON APR 6 2015
HIGH PRESSURE ACROSS MANITOBA WILL MOVE SOUTHEAST TONIGHT AND INITIALLY
MAINTAIN VFR CONDITIONS FROM KMOT-KBIS-KJMS. LOW PRESSURE FROM
MONTANA INTO WYOMING WILL MOVE EAST. EXPECT IFR IN LOW CLOUDS AND
SNOW AT KISN. KDIK WILL INITIALLY BE VFR...THEN GRADUALLY
DETERIORATED TO IFR AFTER 06Z. AS THE TROUGH MOVES EAST KMOT-KBIS-
KJMS WILL ALSO DETERIORATE TO IFR IN LOW CLOUDS AND SNOW AFTER
09Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...NH
LONG TERM...AJ
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1249 PM CDT SUN APR 5 2015
.UPDATE...
ISSUED AT 1249 PM CDT SUN APR 5 2015
THE PREVIOUS 00Z HIGH RES MODELS OUTPERFORMED THE LATEST 12Z
MODELS AS FAR AS THE NOW PERIOD GOES...SO WILL MAINTAIN MUCH WHAT
WAS DONE WITH THE LAST FORECAST ISSUANCE.
SAME THINKING AS BEFORE...LARGE AREA OF SNOW ACROSS THE NORTHWEST
AND NORTH CENTRAL WILL DECREASE IN COVERAGE AS FORCING ALOFT
DESCRIBED IN THE PREVIOUS DISCUSSION MOVES OUT OF THE REGION. AN
INCH OR TWO OF SNOW WILL BE POSSIBLE BEFORE THIS ROUND OF
PRECIPITATION IS OVER THROUGH THIS AFTERNOON.
UPDATE
ISSUED AT 1018 AM CDT SUN APR 5 2015
HIGH RES 00Z ARW/NMM ARE LEADING THE PACK AS FAR AS VERIFICATION
WITH RADAR RETURNS THIS MORNING...ALTHOUGH A TAD FAST (AROUND 3
HOURS) WITH THEIR PROJECTIONS OF RADAR REFLECTIVITY. WILL ADJUST
THIS TIMING ERROR AND FOLLOW THEIR LEAD...EACH OF WHICH SHOW A
LARGE AREA OF LIGHT WITH EMBEDDED MODERATE PRECIPITATION ACROSS
MUCH OF MY NORTHWEST AND NORTH CENTRAL NOW THROUGH EARLY/MID
AFTERNOON MAINLY NORTH OF I94. THIS RECENT DEVELOPMENT OF
PRECIPITATION IS IN RESPONSE TO AN EMBEDDED S/WV APPROACHING FROM
THE WEST AND INCREASINGLY FAVORABLE UPPER LEVEL DIVERGENT FLOW AS
THE TAIL END OF A JET STREAK MOVES OVER THE DAKOTAS. COVERAGE AND
INTENSITY OF PRECIPITATION SHOULD DECREASE THROUGH THE AFTERNOON
HOURS AS FORCING WANES.
MAIN ADJUSTMENTS WITH THIS FORECAST ISSUANCE WAS TO INCREASE POPS
THIS MORNING THROUGH 21Z...ALSO NUDGING TEMPERATURES DOWN A BIT
ACROSS THE NORTH AS I DON`T SEE HOW THEY WILL WARM MUCH GIVEN THE
CLOUD COVER...FALLING SNOW...AND A COLD EASTERLY FLOW.
THE WEST WILL THEN BE THE MOST FAVORED AREA FOR SNOW TONIGHT.
UPDATE ISSUED AT 654 AM CDT SUN APR 5 2015
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE OTHER THAN TO
BLEND TO OBSERVED TRENDS THROUGH 1130 UTC AS THE ONGOING FORECAST
IS WELL SUPPORTED BY THE 09-10 UTC HRRR ITERATIONS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CDT SUN APR 5 2015
MAIN WEATHER CONCERN SUNDAY WILL BE SNOW NORTH...MAINLY ALONG AND
NORTH OF HIGHWAY 2. CHANCES FOR PRECIPITATION DWINDLE FARTHER SOUTH
TODAY...BUT CHANCES FOR PRECIPITATION WILL AGAIN INCREASE SUNDAY
NIGHT AND BEYOND ACROSS WESTERN AND CENTRAL NORTH DAKOTA.
THE LATEST WATER VAPOR IMAGERY SHOWS A BROAD/MOIST WESTERLY FLOW
WITH MULTIPLE WEAK SHORTWAVES EMBEDDED WITHIN THE FLOW...ALL BEING
EJECTED FROM A CLOSED UPPER LOW OFF OF VANCOUVER ISLAND. AT THE
SURFACE HIGH PRESSURE OVER MANITOBA AND LOW PRESSURE OVER WYOMING
WITH A FRONTAL BOUNDARY DRAPED ACROSS CENTRAL AND SOUTHERN SOUTH
DAKOTA. THIS CONTINUES TO INDUCE AN EASTERLY LOW LEVEL FLOW ACROSS
WESTERN AND CENTRAL NORTH DAKOTA. LOW LEVEL COLD AIR ADVECTION
WITH WEST TO SOUTHWEST WINDS ALOFT IN CONJUNCTION WITH MULTIPLE
SHORTWAVES AND JET STREAKS ALOFT WILL RESULT IN PERIODS OF LIGHT
PRECIPITATION THROUGH THE SHORT TERM PERIOD. LATEST FOG/STRATUS
IMAGERY LOOP AND SURFACE OBSERVATIONS SHOW THE AREA OF STRATUS
STRETCHES FROM CROSBY TO MINOT AND EAST INTO RUGBY. MINOT DOPPLER
RADAR CONTINUES WITH EARLIER TRENDS WITH INCREASING REFLECTIVITY`S
AS AREAS OF LIGHT SNOW PROPAGATE FROM WEST TO EAST. THE HRRR
COMPOSITE REFLECTIVITY HAS HAD A GOOD HANDLE ON PAST RADAR TRENDS
AND HAVE UTILIZED IT ALONG WITH THE NAM/GFS FOR POPS IN THE NORTH
TODAY. THE HIGHEST PROBABILITY OF PRECIPITATION SUNDAY REMAINS
ACROSS THE NORTH WHERE SEVERAL SHORTWAVES ALONG WITH A 110KT JET
STREAK WILL ENHANCE VERTICAL MOTION. THIS WILL BEGIN TO WANE BY
LATE AFTERNOON. CURRENT BISMARCK RADAR SHOWS MUCH WEAKER RETURNS
AND EXPECT POPS TO REMAIN MUCH LOWER AS COMPARED TO THE NORTH.
AFTER 00Z MONDAY...EXPECT ANOTHER SLUG OF HIGHER POPS TO IMPINGE
INTO WESTERN NORTH DAKOTA FROM EASTERN MONTANA AS THE NEXT ROUND
OF SHORTWAVES BEGIN TO SHIFT THROUGH.
OVERALL...SNOW TOTALS ALONG AND NORTH OF HIGHWAY 2 THROUGH SUNDAY
NIGHT WILL RANGE FROM 1 TO 3 INCHES. LESS THAN ONE INCH OF SNOWFALL
IS EXPECTED BETWEEN HIGHWAY 2 AND INTERSTATE 94. SOUTH OF INTERSTATE
94...NO SNOWFALL IS EXPECTED.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 325 AM CDT SUN APR 5 2015
AN ACTIVE WEATHER PATTERN WITH MULTIPLE ROUNDS OF PRECIPITATION
HIGHLIGHT THE EXTENDED FORECAST.
THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES SHOW GOOD AGREEMENT ON
PERSISTENT SOUTHWEST FLOW ALOFT ACROSS THE NORTHERN PLAINS MONDAY
THROUGH WEDNESDAY. THEREAFTER...THE WESTERN CONUS UPPER LEVEL LOW
IS FORECAST TO POTENTIALLY PROPAGATE INTO THE NORTHERN PLAINS AND
UPPER MISSISSIPPI VALLEY THURSDAY INTO FRIDAY. THIS PATTERN FAVORS
ACTIVE...WET WEATHER ACROSS WESTERN AND CENTRAL NORTH DAKOTA
THROUGHOUT NEARLY ALL OF THE EXTENDED FORECAST.
FOR MONDAY THROUGH WEDNESDAY...SEVERAL IMPULSES EMBEDDED IN
SOUTHWEST FLOW ALOFT ARE FORECAST TO LEAD TO SEVERAL ROUNDS OF
LIGHT TO MODERATE PRECIPITATION...WITH A DAILY PATTERN OF SNOW
DURING THE LATE EVENING AND OVERNIGHTS...CHANGING OVER TO EITHER A
RAIN/SNOW MIX NORTH OR ALL RAIN SOUTH DURING THE DAY.
OVERALL...THE BEST CHANCE FOR LIGHT TO MODERATE SNOWFALL
ACCUMULATIONS ARE ACROSS THE NORTHWEST AND NORTH CENTRAL WHERE THE
COOLEST TEMPERATURES WILL RESIDE. HOWEVER...WARM GROUND AND RAIN
MIXING IN WILL LIMIT ACCUMULATIONS. GIVEN THE ACCUMULATIONS BEING
SPREAD OUT OVER SEVERAL DAYS...AN ADVISORY IS NOT ANTICIPATED.
UNCERTAINTY INCREASES THURSDAY INTO FRIDAY REGARDING THE
PROPAGATION OF THE WESTERN CONUS LOW INTO THE REGION.
OVERALL...SOUTHERN NORTH DAKOTA HAS THE BEST CHANCE OF BEING
IMPACTED BY THIS STORM SYSTEM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1249 PM CDT SUN APR 5 2015
MVFR TO PERIODS OF IFR CONDITIONS EXPECTED AT KISN-KMOT THIS
AFTERNOON IN LIGHT SNOW AND STRATUS. ELSEWHERE EXPECTING VFR CIGS
AT KDIK/KBIS/KJMS THROUGH 04Z MONDAY. AFTER 04Z MONDAY...CIGS WILL
DETERIORATE TO MVFR AT KBIS/KJMS WITH MVFR-IFR CIGS EXPECTED AT
KDIK. EASTERLY WINDS 15 TO 25 MPH WILL CONTINUE THROUGH THE TAF
PERIOD AT ALL TERMINALS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...KS
LONG TERM...AYD
AVIATION...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1018 AM CDT SUN APR 5 2015
.UPDATE...
ISSUED AT 1018 AM CDT SUN APR 5 2015
HIGH RES 00Z ARW/NMM ARE LEADING THE PACK AS FAR AS VERIFICATION
WITH RADAR RETURNS THIS MORNING...ALTHOUGH A TAD FAST (AROUND 3
HOURS) WITH THEIR PROJECTIONS OF RADAR REFLECTIVITY. WILL ADJUST
THIS TIMING ERROR AND FOLLOW THEIR LEAD...EACH OF WHICH SHOW A
LARGE AREA OF LIGHT WITH EMBEDDED MODERATE PRECIPITATION ACROSS
MUCH OF MY NORTHWEST AND NORTH CENTRAL NOW THROUGH EARLY/MID
AFTERNOON MAINLY NORTH OF I94. THIS RECENT DEVELOPMENT OF
PRECIPITATION IS IN RESPONSE TO AN EMBEDDED S/WV APPROACHING FROM
THE WEST AND INCREASINGLY FAVORABLE UPPER LEVEL DIVERGENT FLOW AS
THE TAIL END OF A JET STREAK MOVES OVER THE DAKOTAS. COVERAGE AND
INTENSITY OF PRECIPITATION SHOULD DECREASE THROUGH THE AFTERNOON
HOURS AS FORCING WANES.
MAIN ADJUSTMENTS WITH THIS FORECAST ISSUANCE WAS TO INCREASE POPS
THIS MORNING THROUGH 21Z...ALSO NUDGING TEMPERATURES DOWN A BIT
ACROSS THE NORTH AS I DON`T SEE HOW THEY WILL WARM MUCH GIVEN THE
CLOUD COVER...FALLING SNOW...AND A COLD EASTERLY FLOW.
THE WEST WILL THEN BE THE MOST FAVORED AREA FOR SNOW TONIGHT.
UPDATE ISSUED AT 654 AM CDT SUN APR 5 2015
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE OTHER THAN TO
BLEND TO OBSERVED TRENDS THROUGH 1130 UTC AS THE ONGOING FORECAST
IS WELL SUPPORTED BY THE 09-10 UTC HRRR ITERATIONS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CDT SUN APR 5 2015
MAIN WEATHER CONCERN SUNDAY WILL BE SNOW NORTH...MAINLY ALONG AND
NORTH OF HIGHWAY 2. CHANCES FOR PRECIPITATION DWINDLE FARTHER SOUTH
TODAY...BUT CHANCES FOR PRECIPITATION WILL AGAIN INCREASE SUNDAY
NIGHT AND BEYOND ACROSS WESTERN AND CENTRAL NORTH DAKOTA.
THE LATEST WATER VAPOR IMAGERY SHOWS A BROAD/MOIST WESTERLY FLOW
WITH MULTIPLE WEAK SHORTWAVES EMBEDDED WITHIN THE FLOW...ALL BEING
EJECTED FROM A CLOSED UPPER LOW OFF OF VANCOUVER ISLAND. AT THE
SURFACE HIGH PRESSURE OVER MANITOBA AND LOW PRESSURE OVER WYOMING
WITH A FRONTAL BOUNDARY DRAPED ACROSS CENTRAL AND SOUTHERN SOUTH
DAKOTA. THIS CONTINUES TO INDUCE AN EASTERLY LOW LEVEL FLOW ACROSS
WESTERN AND CENTRAL NORTH DAKOTA. LOW LEVEL COLD AIR ADVECTION
WITH WEST TO SOUTHWEST WINDS ALOFT IN CONJUNCTION WITH MULTIPLE
SHORTWAVES AND JET STREAKS ALOFT WILL RESULT IN PERIODS OF LIGHT
PRECIPITATION THROUGH THE SHORT TERM PERIOD. LATEST FOG/STRATUS
IMAGERY LOOP AND SURFACE OBSERVATIONS SHOW THE AREA OF STRATUS
STRETCHES FROM CROSBY TO MINOT AND EAST INTO RUGBY. MINOT DOPPLER
RADAR CONTINUES WITH EARLIER TRENDS WITH INCREASING REFLECTIVITY`S
AS AREAS OF LIGHT SNOW PROPAGATE FROM WEST TO EAST. THE HRRR
COMPOSITE REFLECTIVITY HAS HAD A GOOD HANDLE ON PAST RADAR TRENDS
AND HAVE UTILIZED IT ALONG WITH THE NAM/GFS FOR POPS IN THE NORTH
TODAY. THE HIGHEST PROBABILITY OF PRECIPITATION SUNDAY REMAINS
ACROSS THE NORTH WHERE SEVERAL SHORTWAVES ALONG WITH A 110KT JET
STREAK WILL ENHANCE VERTICAL MOTION. THIS WILL BEGIN TO WANE BY
LATE AFTERNOON. CURRENT BISMARCK RADAR SHOWS MUCH WEAKER RETURNS
AND EXPECT POPS TO REMAIN MUCH LOWER AS COMPARED TO THE NORTH.
AFTER 00Z MONDAY...EXPECT ANOTHER SLUG OF HIGHER POPS TO IMPINGE
INTO WESTERN NORTH DAKOTA FROM EASTERN MONTANA AS THE NEXT ROUND
OF SHORTWAVES BEGIN TO SHIFT THROUGH.
OVERALL...SNOW TOTALS ALONG AND NORTH OF HIGHWAY 2 THROUGH SUNDAY
NIGHT WILL RANGE FROM 1 TO 3 INCHES. LESS THAN ONE INCH OF SNOWFALL
IS EXPECTED BETWEEN HIGHWAY 2 AND INTERSTATE 94. SOUTH OF INTERSTATE
94...NO SNOWFALL IS EXPECTED.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 325 AM CDT SUN APR 5 2015
AN ACTIVE WEATHER PATTERN WITH MULTIPLE ROUNDS OF PRECIPITATION
HIGHLIGHT THE EXTENDED FORECAST.
THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES SHOW GOOD AGREEMENT ON
PERSISTENT SOUTHWEST FLOW ALOFT ACROSS THE NORTHERN PLAINS MONDAY
THROUGH WEDNESDAY. THEREAFTER...THE WESTERN CONUS UPPER LEVEL LOW
IS FORECAST TO POTENTIALLY PROPAGATE INTO THE NORTHERN PLAINS AND
UPPER MISSISSIPPI VALLEY THURSDAY INTO FRIDAY. THIS PATTERN FAVORS
ACTIVE...WET WEATHER ACROSS WESTERN AND CENTRAL NORTH DAKOTA
THROUGHOUT NEARLY ALL OF THE EXTENDED FORECAST.
FOR MONDAY THROUGH WEDNESDAY...SEVERAL IMPULSES EMBEDDED IN
SOUTHWEST FLOW ALOFT ARE FORECAST TO LEAD TO SEVERAL ROUNDS OF
LIGHT TO MODERATE PRECIPITATION...WITH A DAILY PATTERN OF SNOW
DURING THE LATE EVENING AND OVERNIGHTS...CHANGING OVER TO EITHER A
RAIN/SNOW MIX NORTH OR ALL RAIN SOUTH DURING THE DAY.
OVERALL...THE BEST CHANCE FOR LIGHT TO MODERATE SNOWFALL
ACCUMULATIONS ARE ACROSS THE NORTHWEST AND NORTH CENTRAL WHERE THE
COOLEST TEMPERATURES WILL RESIDE. HOWEVER...WARM GROUND AND RAIN
MIXING IN WILL LIMIT ACCUMULATIONS. GIVEN THE ACCUMULATIONS BEING
SPREAD OUT OVER SEVERAL DAYS...AN ADVISORY IS NOT ANTICIPATED.
UNCERTAINTY INCREASES THURSDAY INTO FRIDAY REGARDING THE
PROPAGATION OF THE WESTERN CONUS LOW INTO THE REGION.
OVERALL...SOUTHERN NORTH DAKOTA HAS THE BEST CHANCE OF BEING
IMPACTED BY THIS STORM SYSTEM.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 1018 AM CDT SUN APR 5 2015
IFR CIGS AT KMOT WILL LIFT TO MVFR BY 15-18Z AS LIGHT SNOW
COMMENCES. MVFR CIGS WILL DEVELOP AT KISN ALONG WITH LIGHT SNOW BY
15-18Z SUNDAY. ELSEWHERE EXPECTING VFR CIGS AT KDIK/KBIS/KJMS THROUGH
04Z MONDAY. AFTER 04Z MONDAY...CIGS WILL DETERIORATE TO MVFR AT
KBIS/KJMS WITH IFR CIGS EXPECTED AT KDIK. EASTERLY WINDS 15 TO 25
MPH WILL CONTINUE THROUGH THE TAF PERIOD AT ALL TERMINALS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...KS
LONG TERM...AYD
AVIATION...AYD/NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
655 AM CDT SUN APR 5 2015
.UPDATE...
ISSUED AT 654 AM CDT SUN APR 5 2015
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE OTHER THAN TO
BLEND TO OBSERVED TRENDS THROUGH 1130 UTC AS THE ONGOING FORECAST
IS WELL SUPPORTED BY THE 09-10 UTC HRRR ITERATIONS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CDT SUN APR 5 2015
MAIN WEATHER CONCERN SUNDAY WILL BE SNOW NORTH...MAINLY ALONG AND
NORTH OF HIGHWAY 2. CHANCES FOR PRECIPITATION DWINDLE FARTHER SOUTH
TODAY...BUT CHANCES FOR PRECIPITATION WILL AGAIN INCREASE SUNDAY
NIGHT AND BEYOND ACROSS WESTERN AND CENTRAL NORTH DAKOTA.
THE LATEST WATER VAPOR IMAGERY SHOWS A BROAD/MOIST WESTERLY FLOW
WITH MULTIPLE WEAK SHORTWAVES EMBEDDED WITHIN THE FLOW...ALL BEING
EJECTED FROM A CLOSED UPPER LOW OFF OF VANCOUVER ISLAND. AT THE
SURFACE HIGH PRESSURE OVER MANITOBA AND LOW PRESSURE OVER WYOMING
WITH A FRONTAL BOUNDARY DRAPED ACROSS CENTRAL AND SOUTHERN SOUTH
DAKOTA. THIS CONTINUES TO INDUCE AN EASTERLY LOW LEVEL FLOW ACROSS
WESTERN AND CENTRAL NORTH DAKOTA. LOW LEVEL COLD AIR ADVECTION
WITH WEST TO SOUTHWEST WINDS ALOFT IN CONJUNCTION WITH MULTIPLE
SHORTWAVES AND JET STREAKS ALOFT WILL RESULT IN PERIODS OF LIGHT
PRECIPITATION THROUGH THE SHORT TERM PERIOD. LATEST FOG/STRATUS
IMAGERY LOOP AND SURFACE OBSERVATIONS SHOW THE AREA OF STRATUS
STRETCHES FROM CROSBY TO MINOT AND EAST INTO RUGBY. MINOT DOPPLER
RADAR CONTINUES WITH EARLIER TRENDS WITH INCREASING REFLECTIVITY`S
AS AREAS OF LIGHT SNOW PROPAGATE FROM WEST TO EAST. THE HRRR
COMPOSITE REFLECTIVITY HAS HAD A GOOD HANDLE ON PAST RADAR TRENDS
AND HAVE UTILIZED IT ALONG WITH THE NAM/GFS FOR POPS IN THE NORTH
TODAY. THE HIGHEST PROBABILITY OF PRECIPITATION SUNDAY REMAINS
ACROSS THE NORTH WHERE SEVERAL SHORTWAVES ALONG WITH A 110KT JET
STREAK WILL ENHANCE VERTICAL MOTION. THIS WILL BEGIN TO WANE BY
LATE AFTERNOON. CURRENT BISMARCK RADAR SHOWS MUCH WEAKER RETURNS
AND EXPECT POPS TO REMAIN MUCH LOWER AS COMPARED TO THE NORTH.
AFTER 00Z MONDAY...EXPECT ANOTHER SLUG OF HIGHER POPS TO IMPINGE
INTO WESTERN NORTH DAKOTA FROM EASTERN MONTANA AS THE NEXT ROUND
OF SHORTWAVES BEGIN TO SHIFT THROUGH.
OVERALL...SNOW TOTALS ALONG AND NORTH OF HIGHWAY 2 THROUGH SUNDAY
NIGHT WILL RANGE FROM 1 TO 3 INCHES. LESS THAN ONE INCH OF SNOWFALL
IS EXPECTED BETWEEN HIGHWAY 2 AND INTERSTATE 94. SOUTH OF INTERSTATE
94...NO SNOWFALL IS EXPECTED.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 325 AM CDT SUN APR 5 2015
AN ACTIVE WEATHER PATTERN WITH MULTIPLE ROUNDS OF PRECIPITATION
HIGHLIGHT THE EXTENDED FORECAST.
THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES SHOW GOOD AGREEMENT ON
PERSISTENT SOUTHWEST FLOW ALOFT ACROSS THE NORTHERN PLAINS MONDAY
THROUGH WEDNESDAY. THEREAFTER...THE WESTERN CONUS UPPER LEVEL LOW
IS FORECAST TO POTENTIALLY PROPAGATE INTO THE NORTHERN PLAINS AND
UPPER MISSISSIPPI VALLEY THURSDAY INTO FRIDAY. THIS PATTERN FAVORS
ACTIVE...WET WEATHER ACROSS WESTERN AND CENTRAL NORTH DAKOTA
THROUGHOUT NEARLY ALL OF THE EXTENDED FORECAST.
FOR MONDAY THROUGH WEDNESDAY...SEVERAL IMPULSES EMBEDDED IN
SOUTHWEST FLOW ALOFT ARE FORECAST TO LEAD TO SEVERAL ROUNDS OF
LIGHT TO MODERATE PRECIPITATION...WITH A DAILY PATTERN OF SNOW
DURING THE LATE EVENING AND OVERNIGHTS...CHANGING OVER TO EITHER A
RAIN/SNOW MIX NORTH OR ALL RAIN SOUTH DURING THE DAY.
OVERALL...THE BEST CHANCE FOR LIGHT TO MODERATE SNOWFALL
ACCUMULATIONS ARE ACROSS THE NORTHWEST AND NORTH CENTRAL WHERE THE
COOLEST TEMPERATURES WILL RESIDE. HOWEVER...WARM GROUND AND RAIN
MIXING IN WILL LIMIT ACCUMULATIONS. GIVEN THE ACCUMULATIONS BEING
SPREAD OUT OVER SEVERAL DAYS...AN ADVISORY IS NOT ANTICIPATED.
UNCERTAINTY INCREASES THURSDAY INTO FRIDAY REGARDING THE
PROPAGATION OF THE WESTERN CONUS LOW INTO THE REGION.
OVERALL...SOUTHERN NORTH DAKOTA HAS THE BEST CHANCE OF BEING
IMPACTED BY THIS STORM SYSTEM.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 641 AM CDT SUN APR 5 2015
IFR CIGS AT KMOT WILL LIFT TO MVFR BY 15Z AS LIGHT SNOW COMMENCES.
MVFR CIGS WILL DEVELOP AT KISN ALONG WITH LIGHT SNOW BY 15Z SUNDAY.
ELSEWHERE EXPECTING VFR CIGS AT KDIK/KBIS/KJMS THROUGH 04Z MONDAY.
AFTER 04Z MONDAY...CIGS WILL DETERIORATE TO MVFR AT KBIS/KJMS WITH
IFR CIGS EXPECTED AT KDIK. EASTERLY WINDS 15 TO 25 MPH WILL CONTINUE
THROUGH THE TAF PERIOD AT ALL TERMINALS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...KS
LONG TERM...AYD
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1237 AM CDT SUN APR 5 2015
.UPDATE...
ISSUED AT 1236 AM CDT SUN APR 5 2015
LATEST LOCAL/REGIONAL RADAR SHOWS REFLECTIVITY`S INCREASING OVER
EASTERN MONTANA AND ACROSS NORTHERN NORTH DAKOTA...NORTH OF
HIGHWAY 2. NOTHING BEING REPORTED YET FROM ANY OF THE WEATHER
OBSERVING SITES. HIGH PRESSURE OVER MANITOBA AND LOW PRESSURE IN
EASTERN WYOMING WILL CONTINUE TO INDUCE A EAST TO NORTHEASTERLY
FLOW ACROSS THE STATE. CEILINGS CONTINUE TO LOWER AND THICKEN...ESPECIALLY
OVER THE NORTH IN THE COLDER/MOISTER AIR MASS. MODELS CONTINUE
HAVING TROUBLE INITIALIZING ON CURRENT SCENARIO...HOWEVER THE HRRR
COMPOSITE REFLECTIVITY IS CLOSEST TO REALITY. BASED ON CURRENT
RADAR AND THE HRRR...MAIN ADJUSTEMENT WAS TO SLOW DOWN THE AREAL
COVERAGE OF PRECIPITATION DEVELOPMENT...ESPECIALLY SOUTH OF
HIGHWAY 2 OVERNIGHT THROUGH SUNDAY MORNING. THIS IS IN LINE WITH
THE NAM/GFS 850MB-650MB STRONGEST FRONTOGENESIS AREA AND UPPER
LEVEL VERTICAL MOTION FIELD.
UPDATE ISSUED AT 940 PM CDT SAT APR 4 2015
RADAR SIGNATURES SLOWLY INCREASING ACROSS NORTHERN NORTH DAKOTA.
BOWMAN RADAR AS WELL SHOWS SOME RETURNS THAT ARE LIKELY STILL VIRGA.
CURRENT FORECAST LOOKS GOOD FOR THIS. NO SIGNIFICANT CHANGES TO
FORECAST AT THIS TIME.
UPDATE ISSUED AT 633 PM CDT SAT APR 4 2015
LATEST HRRR RUNS SHOW LOW LEVEL 925 MB NEARLY SATURATED RH FIELDS
MOVE FROM ALONG THE CANADIAN BORDER SOUTHWEST THIS EVENING. EXPECT
THIS TO BECOME MORE PRONOUNCED AFTER SUNSET. ALSO INCREASE CLOUDS
WESTERN NORTH DAKOTA AS A LARGE CIRRUS FIELD IS MOVING EAST INTO
THE STATE. A BRIEF RAIN SHOWER AT ESTEVAN BUT THE CLOUDS HAVE
MORES NORTHEAST. WILL INTRODUCE A SLIGHT CHANCE FOR RAIN AND SNOW
BEFORE MIDNIGHT NORTHWEST. PREVIOUS THINKING WAS TO DELAY UNTIL
AFTER MIDNIGHT...BUT LATEST HRRR DOES INTRODUCE SOME LIGHT PRECIP
AFTER 03Z NORTH.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 305 PM CDT SAT APR 4 2015
FORECAST HIGHLIGHT IN THE SHORT TERM PERIOD WILL BE CHANCES FOR
RAIN AND/OR SNOW TONIGHT INTO SUNDAY...WITH LIGHT SNOW
ACCUMULATIONS POSSIBLE ACROSS THE NORTHWEST AND NORTH CENTRAL.
CURRENTLY...WEST-NORTHWEST FLOW ALOFT WITH A QUASI-STATIONARY
SURFACE BOUNDARY DRAPED NORTHWEST TO SOUTHEAST FROM NORTH CENTRAL
MONTANA TO ACROSS WESTERN AND CENTRAL NORTH DAKOTA. LINGERING MVFR
STRATUS ACROSS MY NORTHEAST EXTENDING BACK NORTHWEST INTO SOUTH
CENTRAL CANADA. THE SKY IS CLEAR TO SCATTERED ELSEWHERE. ROLLA
REPORTING LIGHT SNOW NOW...ALTHOUGH WITH RADAR ECHOS ON THE
DECREASE WILL LEAVE OUT OF THE AFTERNOON FORECAST PACKAGE WITH
ZERO IMPACTS.
CLOUDS INCREASING ACROSS MONTANA WILL EVENTUALLY MOVE INTO AND
DEVELOP ACROSS WESTERN AND CENTRAL NORTH DAKOTA LATER TODAY INTO
THIS EVENING AS ANOTHER SERIES OF MID LEVEL WAVES MOVE INTO THE
REGION. LIFT WILL BE SUPPORTED BY AN EASTERLY UPSLOPE
FLOW REGIME. MODELS DEPICT THE LOW STRATUS ACROSS MY NORTHEAST TO
SLOWLY BUILD SOUTH AND WEST THIS EVENING AS WINDS TURN NORTHEAST
BEHIND A BACKDOOR COLD FRONT MOVING INTO MY NORTH TONIGHT.
SOUTHWARD EXTENT UNCERTAIN BUT APPEARS THE LOWER CIGS WILL BE
CONFINED TO MY NORTHERN COUNTIES.
WILL MAINTAIN THE ONSET OF PRECIPITATION TONIGHT TO AFTER 06Z.
MODELS FAIRLY DRY THROUGH THE MID LEVELS AND WILL TAKE TIME TO
SATURATE. MODEL UNCERTAINTY IS HIGHER THAN I WOULD LIKE...SO KEPT
POPS BELOW LIKELY WORDING THROUGH 12Z. BETTER MODEL AGREEMENT
ACROSS THE NORTH SUNDAY MORNING AND AFTERNOON SO OPTED TO KEEP
LIKELY POPS MAINTAINED FOR THE 12-18Z AND 18-00Z PERIODS. WITH
EXPECTED CLOUDS AND PRECIPITATION...LOWERED DAYTIME HIGHS SUNDAY
ACROSS THE NORTH WHERE WE PROJECT 1 TO NEAR 2 INCHES OF SNOW
THROUGH SUNDAY AFTERNOON.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 305 PM CDT SAT APR 4 2015
AN ACTIVE WEATHER PATTERN THROUGHOUT MUCH OF THE LONG TERM FORECAST
HIGHLIGHTS THE PERIOD.
THE MODELS ARE IN FAIRLY GOOD AGREEMENT WITH A LARGE UPPER LEVEL LOW
PRESSURE TROUGH OVER THE WEST COAST SUNDAY NIGHT EXPANDING AND
MOVING EASTWARD ACROSS THE ROCKIES THROUGH THURSDAY...AND TRAVERSING
SLOWLY EASTWARD ACROSS THE CENTRAL US AND INTO THE GREAT LAKES AREA
BY SATURDAY.
SUNDAY NIGHT THROUGH TUESDAY AFTERNOON:
CHANCES OF RAIN AND SNOW ARE IN EACH DAY/NIGHT OF THE FORECAST
PERIOD SUNDAY NIGHT THROUGH TUESDAY. DURING THIS TIME PERIOD A
SURFACE LOW IS FORECAST TO BE SITUATED OVER THE WESTERN PORTION OF
THE CENTRAL PLAINS WITH A COLD SURFACE HIGH OVER HUDSON BAY/GREAT
LAKES REGION. A PROLONGED PERIOD OF LIGHT RAIN AND LIGHT SNOW IS IN
STORE FOR MUCH OF WESTERN AND CENTRAL NORTH DAKOTA. FORECASTING SNOW
AMOUNTS CONTINUES TO BE PROBLEMATIC WITH EACH MODEL RUN DEPICTING
WHEN/WHERE THE PRECIPITATION WILL OCCUR...AND HENCE DAY/NIGHT
TEMPERATURES ABOVE AND BELOW FREEZING. TODAY`S MODELS SUGGEST THAT
DURING THIS 48-HOUR TIME PERIOD (SUN NIGHT THROUGH TUE AFTN) THAT 1
TO 4 INCHES OF SNOW IS POSSIBLE OVER WESTERN NORTH DAKOTA...WITH A
TRACE TO 2 INCHES OVER PARTS OF CENTRAL NORTH DAKOTA.
TUESDAY NIGHT THROUGH SATURDAY:
ANOTHER SURFACE LOW DEVELOPS IN THE 4-CORNERS AREA AND MOVES EAST
ACROSS THE SOUTHERN PLAINS...THEN LIFTS NORTHEASTWARD TO THE GREAT
LAKES BY SATURDAY. CHANCES OF LIGHT RAIN...SOMETIMES MIXED WITH
LIGHT SNOW...DURING THIS PERIOD WITH SLIGHTLY WARMER CONDITIONS.
LOWS IN THE 30S AND HIGHS FROM THE 40S TUESDAY...WARMING TO THE
UPPER 50S AND LOWER 60S BY SATURDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1236 AM CDT SUN APR 5 2015
CIGS WILL DETERIORATE TO MVFR AT KISN/KMOT BETWEEN 09Z-12Z SUNDAY
AND CONTINUE THROUGH THE TAF PERIOD ALONG WITH PERIODS OF SNOW
MIGRATING ACROSS THESE TERMINALS. THE MVFR CIGS SHOULD FALL SHORT
IN GETTING INTO KBIS/KDIK/KJMS THROUGH THIS TAF PERIOD...EXCEPT AT
KJMS WHERE MVFR CIGS ARE FORCAST BY 02Z MONDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...NH
LONG TERM...JV
AVIATION...KS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1138 PM CDT SAT APR 4 2015
.UPDATE...
ISSUED AT 1137 PM CDT SAT APR 4 2015
A BAND OF MID CLOUD IS BEGINNING TO SHOW UP ON MINOT RADAR...WITH
CIGS AROUND 7K FEET. GFS BEST PICKS UP ON THIS FEATURE...WHILE NAM
IS A BIT FURTHER SOUTH. BOTH MODELS DO GENERATE PRECIP BUT
ALTHOUGH FURTHER SOUTH THAN RADAR...NAM IS MORE REALISTIC IN
DRYING THINGS UP AS IT MOVES EAST WHILE THE GFS IS RATHER BULLISH
WITH QPF ALONG TRI BORDER AREA BETWEEN SASK/ND/MB. THUS WILL ADD
SOME LOW POPS IN USING GFS AS PLACEMENT...BUT KEEP NO
ACCUMULATION. THIS WILL MATCH UP WITH NEIGHBORING OFFICE A BIT
BETTER AS WELL. OVERALL NOT VERY IMPRESSED AS NE FLOW WILL BE HARD
TO OVERCOME...AND THAT STRENGTHENS DURING THE DAY TOMORROW.
UPDATE ISSUED AT 1002 PM CDT SAT APR 4 2015
CURRENT TEMPS ON TRACK. MID LEVEL CLOUDS OVER S CNTRL ND ADVECTING
EAST A BIT FASTER THAN ANTICIPATED SO INCREASED SKY ACROSS THE
SOUTH. 00Z NAM CONTINUES TO HOLD OFF POPS UNTIL AFT 18Z...SO NO
CHANGES MADE TO POPS. OVERALL SNOW POTENTIAL FOR TOWNER COUNTY AND
SURROUNDING AREA LOOKING MINIMAL. NAM DOES SHIFT SOUTHWARD A BAND
ALONG I94 CORRIDOR SUN NIGHT. WILL NOT ADDRESS THIS UPDATE UNTIL
NEW GFS DATA COMES IN.
UPDATE ISSUED AT 700 PM CDT SAT APR 4 2015
FORECAST CHALLENGE FOR TONIGHT WILL BE OVERNIGHT LOWS. CURRENT
CLOUD BAND OVER NORTHEAST ND SHOWING STRIATED APPEARANCE AND
EXPECT A GOOD PORTION OF THIS TO DISSIPATE AS SUN GOES
DOWN...HOWEVER A BIT MOVE OVERCAST ACROSS TOWNER AND CAVALIER
COUNTIES. THIS WILL OBVIOUSLY IMPACT LOWS IF THEY STAY
TOGETHER...HOWEVER WITH NORTHEAST FLOW...DRY AIR ADVECTING IN
SHOULD HELP ERODE THIS AREA UNTIL MORE WIDESPREAD CIGS OVER SW MB
SHIFT SOUTHEAST. USED TEMP BIASED TRENDS FOR NEW OVERNIGHT
CURVE...WHICH BRINGS COLDER AIR FROM NORTHEAST TO SOUTHWEST AND
OVERNIGHT LOWS QUITE CHILLY IN THE FAR NORTHEAST. HRRR DOES BRING
SOME PRECIP INTO TOWNER COUNTY TONIGHT BUT WILL HOLD OFF AS NOT
MUCH SHOWING UP ON RADAR IN AT THIS POINT.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 250 PM CDT SAT APR 4 2015
THE FEW ECHOES ON RADAR THAT TRACKED THROUGH THE KDVL REGION
ERODED AS THEY MOVED INTO THE NORTHERN RED RIVER VALLEY. NOT MUCH
LEFT ON RADAR UPSTREAM SO WILL KEEP A DRY FORECAST INTO TONIGHT.
ONLY THING THAT REMAINS IS A BAND OF CLOUDS OVER NORTHERN MN BACK
INTO SOUTHERN CANADA. THERE ARE SOME BREAKS OVER THE NORTHERN RED
RIVER VALLEY. WILL KEEP THE IDEA OF PARTLY TO MOSTLY CLOUDY
TONIGHT. MOST AREAS WILL PROBABLY BE PARTLY CLOUDY THIS EVENING
WITH MORE CLOUDS ARRIVING LATE. WITH LIGHTER WINDS LOWS WILL
DEPEND HIGHLY ON THESE CLOUD TRENDS. MODELS CONTINUE TO BACK OFF
ON THE SUNDAY PCPN BAND. AT THIS POINT DO NOT SEE ANYTHING GETTING
CLOSE TO THE FA UNTIL AFTER 18Z. AT THAT POINT THE 12Z
GFS/NAM/ECMWF ONLY BRING A GLANCING SHOT TO THE KDVL REGION. HOW
THINGS EVOLVE FROM THEN ARE STILL PRETTY MUDDLED. HOWEVER THE
TREND SEEMS TO BE FOR ANOTHER BAND TO DEVELOP ACROSS THE SOUTHERN
FA AND HANG AROUND INTO MONDAY. FOR THE MOST PART THIS WOULD BE
ALONG AND SOUTH OF INTERSTATE 94 IN ND AND HIGHWAY 10 IN MN. HARD
TO BELIEVE THERE WOULD BE MUCH FOR PCPN AMOUNTS. THE ECMWF IS
ACTUALLY THE MOST ROBUST...SHOWING A TENTH OF AN INCH OR TWO.
HOWEVER CONFIDENCE REMAINS PRETTY LOW.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 250 PM CDT SAT APR 4 2015
THE LOW CONFIDENCE FORECAST ON MONDAY CONTINUES INTO TUE. 12Z
GFS/NAM SHOW ANOTHER PCPN BAND DEVELOPING OVER THE AREA. GFS SHOWS
AMOUNTS OF A QUARTER INCH OR GREATER. MEANWHILE THE 12Z ECMWF IS
BASICALLY DRY. MAINTAINED SOME LOW PCPN CHANCES TO AVOID FLIP
FLOPPING IN THE FORECAST AND WILL HOPE LATER MODEL RUNS COME INTO
BETTER AGREEMENT.
FOR TUE NIGHT THROUGH SAT...MODELS ARE HINTING AT A POTENTIALLY
ACTIVE PERIOD FOR AT LEAST THE SOUTHERN 1/3 OF THE FORECAST AREA.
THERE ARE PLENTY OF DIFFERENCES IN REGARD TO TIMING AND PLACEMENT OF
ANY QPF. THERE COULD BE A SLOW MOVING STORM SYSTEM THAT AFFECTS THE
SOUTH LATE THU INTO SAT...THAT WOULD BRING RAIN DURING THE DAY AND
PERHAPS A RAIN/SNOW MIX AT NIGHT. TEMPS SHOULD BE AROUND NORMAL AND
HINGE ON HOW MUCH INSOLATION OCCURS. AT THIS POINT THE WARMER AREAS
COULD BE IN THE NORTH WHERE THERE IS MORE SUNSHINE...BUT FAIRLY LOW
CONFIDENCE OVERALL GIVEN MODEL UNCERTAINTIES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1137 PM CDT SAT APR 4 2015
HIGH AND MID CLOUD WILL SPREAD ACROSS AREA TONIGHT AND LOWER VFR
CIGS WILL ARRIVE TOMORROW MORNING. DVL MAY SEE MVFR CIGS TOMORROW
AFTN AND POSSIBLE SOME LIGHT SNOW NOT EXPECTED TO REDUCE VSBYS. NE
FLOW WILL CONTINUE THROUGHOUT TAF PERIOD WITH WINDS STRONGEST IN
CENTRAL ND.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...SPEICHER
SHORT TERM...GODON
LONG TERM...GODON/DK
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
701 PM EDT SUN APR 5 2015
.SYNOPSIS...
A STATIONARY FRONT ACROSS SOUTHERN LOWER MICHIGAN AND LAKE ERIE
INTO NORTHWEST PENNSYLVANIA WILL DRIFT NORTH AND SOUTH INTO AND
OUT OF THE AREA TONIGHT THROUGH MONDAY NIGHT. TUESDAY LOW PRESSURE
WILL MOVE ACROSS NORTHERN OHIO ALONG THE FRONT FORCING IT SOUTH TO
CENTRAL OHIO BY WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
SURFACE BOUNDARY IS MOVING SOUTHWARD ACROSS LAKE ERIE BUT SHOULD
CAUSE LITTLE IMPACT TO PRECIPITATION CHANCES. HOWEVER THE NORTHERLY
FLOW OFF OF LAKE ERIE WILL HELP TO COOL TEMPERATURES A BIT FASTER
THIS EVENING. ACTUALLY LOOKS LIKE WE COULD SEE A QUICK 10 DEGREE
DROP IN TEMPERATURE WITH THE WIND SHIFT.
OTHER THAN THIS SHALLOW SURFACE BOUNDARY THERE IS NOT MUCH ELSE
GOING ON THAT WILL IMPACT THE PREVIOUS FORECAST.
PREVIOUS DISCUSSION...
FOR THE EVENING ANY REMAINING PRECIP SHOULD LIFT NORTHEAST OF
NWRN PA AS THE FRONTAL ZONE ALOFT SHIFT NORTH. AT THE SURFACE THE
HRRR AND RUC CONTINUE TO SHOW SURFACE WINDS TURNING NORTHEAST WITH
TEMPS DROPPING OFF AFTER ABOUT 21-22Z IN WHAT MAY BE MORE A FACTOR
OF THE GRADIENT WIND DECOUPLING AND LAKE INFLUENCES TAKE OVER FOR
A FEW HOURS. FOR MOST THE EVENING SHOULD BEGIN CLEAR TO PARTLY
CLOUDY. OVERNIGHT HOWEVER THE GFS AND NAM BOTH AGREE ON INCREASING
CLOUDS AS MOISTURE MOVES BACK INTO THE AREA IN DEEP S-SWLY FLOW
OFF THE GLFMX ALTHOUGH EXPECTING NO PRECIP OVERNIGHT. LOWS UPPER
30S TO LOWER 40S.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
MODELS CONTINUE TO SUPPORT THE STATIONARY FRONT WAFFLING NORTH AND
SOUTH OF THE AREA TONIGHT THROUGH MONDAY NIGHT BEFORE DRIFTING
SOUTH BEHIND LOW PRESSURE TUESDAY THROUGH WEDNESDAY. FOR MONDAY
EXPECT CLOUDS TO QUICKLY FILL IN AS MOISTURE FROM THE SOUTH
OVERRUNS THE AREA. CORE OF THE HIGHER RH MOVES ACROSS THE EASTERN
HALF OF THE AREA AND MODELS DEVELOP LIFT ACROSS THE AREA DURING
THE MID DAY IN RESPONSE TO A WEAK WAVE ALOFT. SINCE FORCING IS NOT
STRONG WILL HAVE ONLY CHANCE POPS FOR THE AREA. LOOKING AT THE NAM
AND SREF IT APPEARS THAT MONDAY THE FRONT WILL REMAIN NORTH OF THE
AREA WITH THE MAV SHOWING SWLY FLOW AT KERI ALL DAY. GUIDANCE
TEMPS OF UPPER 50S AND LOWER 60S LOOK FINE. MONDAY NIGHT THE FIRST
HALF OF THE NIGHT MODELS SHOW THE MONDAY WAVE AND DEEP MOISTURE
MOVING EAST WHILE A STRONGER SHORT WAVE MOVES IN FROM THE WEST
AFTER MIDNIGHT. MODELS PRINT OUT A QUARTER TO A HALF INCH OF RAIN
ACROSS THE AREA MOST WEST. WILL GO WITH CAT POPS WEST AND LIKELY
ELSEWHERE. TUESDAY WILL BEGIN WITH CAP POPS DROPPING TO LIKELY
IN THE AFTERNOON AS THE WAVE MOVES EAST. WILL ALSO NEED TO MENTION
THUNDER AS CAPES GO OVER 1000 J/KG IN THE AFTERNOON. CONTINUED WET
TUESDAY NIGHT AND WEDNESDAY. TEMPS SHOULD CONTINUE MILD IN THE
SOUTH TUESDAY WITH MID AND UPPER 60S BUT 10 DEGREES LOWER NORTH.
WEDNESDAY 40S NORTH AND 50S SOUTH BEHIND THE FRONT.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
ACTIVE WEATHER WITH INFLUX OF GULF MOISTURE CONTINUES FOR AT LEAST
THE FIRST PART OF THE EXTENDED FORECAST. A CLOSED UPPER LEVEL LOW
WILL APPROACH FROM THE PLAINS WITH THE NEXT SURGE OF MOISTURE
EXPECTED TO PUSH NORTHEAST ACROSS THE AREA ON THURSDAY AFTERNOON AND
NIGHT. SURFACE WARM FRONT ALSO EXPECTED TO MAKE A PUSH TO THE NORTH
DURING THIS TIME AND HIGH TEMPERATURES ON THURSDAY WILL DEPEND ON
ITS PROGRESS. WE SHOULD BE IN THE WARM SECTOR ON FRIDAY WITH SHOWERS
LIKELY AND A CHANCE OF THUNDERSTORMS. PRECIP TRIES TO SHIFT EAST
LATE IN THE DAY AS MID-LEVEL DRY SLOT ARRIVES BUT TIMING WILL LIKELY
CHANGE WITH A CHANCE THAT THE UPPER LOW COULD SLOW DOWN. AT THIS
TIME...THE GFS IS A FAST OUTLIER FROM THE ECMWF AND GEM WITH THE
SPEED OF THE FRONT ON FRIDAY...AND IS EVEN ON THE FAST SIDE OF THE
GFS ENSEMBLE MEMBERS. WILL LEAN TOWARDS THE SLOWER SOLUTION ON
FRIDAY WITH MILD CONDITIONS LINGERING INTO FRIDAY NIGHT. COVERAGE OF
SHOWERS WILL HAVE AN IMPACT ON TEMPERATURES ON FRIDAY...ALTHOUGH
MOST AREAS SHOULD AT LEAST REACH THE 60S.
A WEAK FRONT WILL HELP TO DRY OUT THE AIRMASS FOR THE WEEKEND. THE
COOLER AIR WILL JUST BRUSH THE AREA AS THE UPPER LOW PASSES TO THE
NORTH ON SATURDAY SO TEMPERATURES SHOULD ONLY DROP BACK TO NEAR
NORMAL.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
BREEZY SOUTHWEST WINDS OF 15-20 KNOTS WITH GUSTS OF 25-30 KNOTS WILL
CONTINUE THIS AFTERNOON AT ALL SITES BUT ERI. ERI IS CLOSE TO A
STALLED FRONTAL BOUNDARY OVER THE LAKE AND COULD SEE WINDS SWITCH TO
THE NE OR GO VARIABLE AFTER 22Z AS THIS BOUNDARY SINKS SOUTH.
OTHERWISE VFR CONDITIONS EXPECTED THROUGH THE TAF CYCLE. CEILINGS
WILL LOWER TO NEAR 5K FEET EARLY MONDAY.
.OUTLOOK...FREQUENT PERIODS OF NON VFR CONDITIONS MONDAY
NIGHT THROUGH FRIDAY.
&&
.MARINE...
A STATIONARY FRONT DRAPED ACROSS LAKE ERIE WILL SHIFT TOWARDS THE
SOUTH SHORE OVERNIGHT AND THEN PUSH BACK NORTH ON MONDAY. THE
FRONTAL BOUNDARY WILL FINALLY PUSH SOUTH ON TUESDAY WITH NORTHEAST
WINDS OF 10 TO 20 KNOTS DEVELOPING AND CONTINUING INTO WEDNESDAY.
A WARM FRONT WILL LIFT BACK NORTH ON THURSDAY WITH SOUTHERLY WINDS
DEVELOPING. A WEAK COLD FRONT WILL CROSS THE LAKE ON FRIDAY NIGHT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK/MULLEN
SHORT TERM...TK
LONG TERM...KEC
AVIATION...KEC
MARINE...KEC
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
346 PM EDT SUN APR 5 2015
.SYNOPSIS...
A STATIONARY FRONT ACROSS SOUTHERN LOWER MICHIGAN AND LAKE ERIE
INTO NORTHWEST PENNSYLVANIA WILL DRIFT NORTH AND SOUTH INTO AND
OUT OF THE AREA TONIGHT THROUGH MONDAY NIGHT. TUESDAY LOW PRESSURE
WILL MOVE ACROSS NORTHERN OHIO ALONG THE FRONT FORCING IT SOUTH TO
CENTRAL OHIO BY WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
FOR THE EVENING ANY REMAINING PRECIP SHOULD LIFT NORTHEAST OF NWRN
PA AS THE FRONTAL ZONE ALOFT SHIFT NORTH. AT THE SURFACE THE HRRR
AND RUC CONTINUE TO SHOW SURFACE WINDS TURNING NORTHEAST WITH
TEMPS DROPPING OFF AFTER ABOUT 21-22Z IN WHAT MAY BE MORE A FACTOR
OF THE GRADIENT WIND DECOUPLING AND LAKE INFLUENCES TAKE OVER FOR
A FEW HOURS. FOR MOST THE EVENING SHOULD BEGIN CLEAR TO PARTLY
CLOUDY. OVERNIGHT HOWEVER THE GFS AND NAM BOTH AGREE ON INCREASING
CLOUDS AS MOISTURE MOVES BACK INTO THE AREA IN DEEP S-SWLY FLOW
OFF THE GLFMX ALTHOUGH EXPECTING NO PRECIP OVERNIGHT. LOWS UPPER
30S TO LOWER 40S.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
MODELS CONTINUE TO SUPPORT THE STATIONARY FRONT WAFFLING NORTH AND
SOUTH OF THE AREA TONIGHT THROUGH MONDAY NIGHT BEFORE DRIFTING
SOUTH BEHIND LOW PRESSURE TUESDAY THROUGH WEDNESDAY. FOR MONDAY
EXPECT CLOUDS TO QUICKLY FILL IN AS MOISTURE FROM THE SOUTH
OVERRUNS THE AREA. CORE OF THE HIGHER RH MOVES ACROSS THE EASTERN
HALF OF THE AREA AND MODELS DEVELOP LIFT ACROSS THE AREA DURING
THE MID DAY IN RESPONSE TO A WEAK WAVE ALOFT. SINCE FORCING IS NOT
STRONG WILL HAVE ONLY CHANCE POPS FOR THE AREA. LOOKING AT THE NAM
AND SREF IT APPEARS THAT MONDAY THE FRONT WILL REMAIN NORTH OF THE
AREA WITH THE MAV SHOWING SWLY FLOW AT KERI ALL DAY. GUIDANCE
TEMPS OF UPPER 50S AND LOWER 60S LOOK FINE. MONDAY NIGHT THE FIRST
HALF OF THE NIGHT MODELS SHOW THE MONDAY WAVE AND DEEP MOISTURE
MOVING EAST WHILE A STRONGER SHORT WAVE MOVES IN FROM THE WEST
AFTER MIDNIGHT. MODELS PRINT OUT A QUARTER TO A HALF INCH OF RAIN
ACROSS THE AREA MOST WEST. WILL GO WITH CAT POPS WEST AND LIKELY
ELSEWHERE. TUESDAY WILL BEGIN WITH CAP POPS DROPPING TO LIKELY
IN THE AFTERNOON AS THE WAVE MOVES EAST. WILL ALSO NEED TO MENTION
THUNDER AS CAPES GO OVER 1000 J/KG IN THE AFTERNOON. CONTINUED WET
TUESDAY NIGHT AND WEDNESDAY. TEMPS SHOULD CONTINUE MILD IN THE
SOUTH TUESDAY WITH MID AND UPPER 60S BUT 10 DEGREES LOWER NORTH.
WEDNESDAY 40S NORTH AND 50S SOUTH BEHIND THE FRONT.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
ACTIVE WEATHER WITH INFLUX OF GULF MOISTURE CONTINUES FOR AT LEAST
THE FIRST PART OF THE EXTENDED FORECAST. A CLOSED UPPER LEVEL LOW
WILL APPROACH FROM THE PLAINS WITH THE NEXT SURGE OF MOISTURE
EXPECTED TO PUSH NORTHEAST ACROSS THE AREA ON THURSDAY AFTERNOON AND
NIGHT. SURFACE WARM FRONT ALSO EXPECTED TO MAKE A PUSH TO THE NORTH
DURING THIS TIME AND HIGH TEMPERATURES ON THURSDAY WILL DEPEND ON
ITS PROGRESS. WE SHOULD BE IN THE WARM SECTOR ON FRIDAY WITH SHOWERS
LIKELY AND A CHANCE OF THUNDERSTORMS. PRECIP TRIES TO SHIFT EAST
LATE IN THE DAY AS MID-LEVEL DRY SLOT ARRIVES BUT TIMING WILL LIKELY
CHANGE WITH A CHANCE THAT THE UPPER LOW COULD SLOW DOWN. AT THIS
TIME...THE GFS IS A FAST OUTLIER FROM THE ECMWF AND GEM WITH THE
SPEED OF THE FRONT ON FRIDAY...AND IS EVEN ON THE FAST SIDE OF THE
GFS ENSEMBLE MEMBERS. WILL LEAN TOWARDS THE SLOWER SOLUTION ON
FRIDAY WITH MILD CONDITIONS LINGERING INTO FRIDAY NIGHT. COVERAGE OF
SHOWERS WILL HAVE AN IMPACT ON TEMPERATURES ON FRIDAY...ALTHOUGH
MOST AREAS SHOULD AT LEAST REACH THE 60S.
A WEAK FRONT WILL HELP TO DRY OUT THE AIRMASS FOR THE WEEKEND. THE
COOLER AIR WILL JUST BRUSH THE AREA AS THE UPPER LOW PASSES TO THE
NORTH ON SATURDAY SO TEMPERATURES SHOULD ONLY DROP BACK TO NEAR
NORMAL.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
BREEZY SOUTHWEST WINDS OF 15-20 KNOTS WITH GUSTS OF 25-30 KNOTS WILL
CONTINUE THIS AFTERNOON AT ALL SITES BUT ERI. ERI IS CLOSE TO A
STALLED FRONTAL BOUNDARY OVER THE LAKE AND COULD SEE WINDS SWITCH TO
THE NE OR GO VARIABLE AFTER 22Z AS THIS BOUNDARY SINKS SOUTH.
OTHERWISE VFR CONDITIONS EXPECTED THROUGH THE TAF CYCLE. CEILINGS
WILL LOWER TO NEAR 5K FEET EARLY MONDAY.
.OUTLOOK...FREQUENT PERIODS OF NON VFR CONDITIONS MONDAY
NIGHT THROUGH FRIDAY.
&&
.MARINE...
A STATIONARY FRONT DRAPED ACROSS LAKE ERIE WILL SHIFT TOWARDS THE
SOUTH SHORE OVERNIGHT AND THEN PUSH BACK NORTH ON MONDAY. THE
FRONTAL BOUNDARY WILL FINALLY PUSH SOUTH ON TUESDAY WITH NORTHEAST
WINDS OF 10 TO 20 KNOTS DEVELOPING AND CONTINUING INTO WEDNESDAY.
A WARM FRONT WILL LIFT BACK NORTH ON THURSDAY WITH SOUTHERLY WINDS
DEVELOPING. A WEAK COLD FRONT WILL CROSS THE LAKE ON FRIDAY NIGHT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK
SHORT TERM...TK
LONG TERM...KEC
AVIATION...KEC
MARINE...KEC
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
925 AM EDT SUN APR 5 2015
.SYNOPSIS...
HIGH PRESSURE OVER THE OHIO VALLEY WILL MOVE OFF THE SOUTHEAST COAST
THIS EVENING. BACK DOOR COLD FRONT WILL LINGER ACROSS EXTREME NE
OH/NW PA TODAY...THEN LIFT NE TONIGHT. A WARM FRONT WILL LIFT
ACROSS THE AREA MONDAY THEN STALL...SETTING UP AN ACTIVE WEATHER
PATTERN THROUGH THE END OF THE WORK WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...ADJUSTED TEMPS THROUGH THE DAY AND INTO THE NIGHT BUT
MAINLY TO REFLECT HRRR RUC AND NAM INDICATIONS THAT THE STATIONARY
FRONT TO OUR NORTH EVENTUALLY DROPS INTO NORTHEAST OHIO LATE THIS
AFTERNOON AND EVENING. COULD ACTUALLY BE COMBINED WITH A LAKE
BREEZE GIVEN TIMING BUT SHOULD ALSO LIFT BACK NORTH OVERNIGHT.
ALSO MADE SMALL ADJUSTMENTS TO SKY GRIDS AND ADDED "LIGHT" TO RAIN
NORTHEAST.
ORIGINAL DISCUSSION...
HIGH PRESSURE CENTERED OVER THE OHIO VALLEY WILL SLIDE EAST AND MOVE
OFF THE SOUTHEAST COAST THIS EVENING. MEANWHILE A BACK DOOR COLD
FRONT MEANDERING ACROSS EXTREME NW PA WILL BE THE FOCUS OF SOME
SHOWERS LATER TODAY. TIMING SHOULD BE LATE ENOUGH THAT PRECIP SHOULD
FALL AS ALL RAIN. FRONT WILL LINGER THERE MOST OF THE DAY AND THEN
LIFT NE LATE THIS AFTERNOON. SHOWERS SHOULD LIFT NE THIS AFTERNOON
WITH THE FRONT.
THE REMAINDER OF THE AREA SHOULD REMAIN DRY. AS FAR AS TEMPS A LOT
WILL MANY SUN BREAKS WE GET THIS AFTERNOON...BUT FOR THE MOST PART SW
OF THE COLD FRONT MOST LOCATIONS WILL SEE TEMPS IN THE 60-65
RANGE. LOCATIONS NE OF THE COLD FRONT HOWEVER WILL STRUGGLE TO GET
INTO THE 50S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
MORE ACTIVE WEATHER PATTERN IS SETTING UP FOR THE WORK WEEK. WARM
FRONT LIFTS OVER THE AREA LATE MONDAY AND BECOMES NEARLY
STATIONARY. BY MIDDAY MONDAY THE RAIN SHOULD BE SPREADING INTO THE
AREA. GULF WIDE OPEN SO PLENTY OF MOISTURE TO TAP INTO. COULD SEE
SOME CONVECTION ON TUESDAY AS CAPES INCREASE TO 1000-1500 J/KG.
COMBINED WITH A LOW LEVEL JET COINCIDES AND AN UPPER LEVEL SHORT
WAVE. THE BEST CHANCE FOR THUNDER WILL BE IN THE SOUTHERN
COUNTIES...WHILE COUNTIES NORTH OF MANSFIELD COULD SEE MAINLY
ISOLATED ELEVATED CONVECTION. PRECIPITABLE WATER VALUES WILL CLIMB
TO AROUND 1.25 INCHES WHICH COULD SUPPORT SOME MODERATE TO HEAVY
RAIN AT TIMES. LOW PRESSURE SYSTEM WILL RIDE ALONG THE BOUNDARY
TUESDAY NIGHT INTO WEDNESDAY...THEN MOVE EAST OF THE AREA DURING THE
DAY WEDNESDAY.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
TEMPERATURES WILL BE ABOVE NORMAL BUT THE POPS ARE TOUGH. THE AREA
WILL BE OR WILL GET INTO THE WARM SECTOR ON THURSDAY SO DEPENDING ON
THE TIMING POPS COULD BE CHANCE OR LIKELY. AT THIS TIME WILL
CONTINUE WITH CHANCE POPS. WE WILL BE IN THE WARM SECTOR THURSDAY
NIGHT SO CONFIDENT THAT CHANCE POPS ARE GOOD. ON FRIDAY A FRONT
TRIES TO MOVE TOWARDS THE AREA AS A LOW MOVES ACROSS THE CENTRAL
GREAT LAKES. THE MODELS MAY NOT AGREE ON THE SYNOPTIC FEATURES BUT
THEY DO ON THE MOISTURE...SO WILL GO WITH LIKELY POPS. ADDED THUNDER
FOR THURSDAY THROUGH FRIDAY AS THE AIRMASS WILL BE UNSTABLE IN THE
WARM SECTOR.
FOR FRIDAY NIGHT THROUGH SATURDAY A CHANCE OF SHOWERS AS A TROF WILL
ROTATE AROUND THE LOW THAT MOVED THROUGH ON FRIDAY. DRYING OUT
SATURDAY NIGHT AS THE LOW AND TROF MOVES NORTH.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL BE MOVING THROUGH THE OHIO VALLEY TODAY WHILE A
FRONTAL BOUNDARY WILL BE SAGGING SOUTH AND SETTING UP FROM
SOUTHERN WISCONSIN ACROSS LAKE ERIE TO NORTHWEST PENNSYLVANIA.
WEAK IMPULSES MOVING ALONG THE FRONT WILL CAUSE A THREAT OF
SHOWERS TODAY OVER NW PA...COULD BE SOME MVFR CONDITIONS AT TIMES
NEAR THE FRONTAL BOUNDARY. THE BOUNDARY WILL LIFT NORTH TONIGHT.
ELSEWHERE VFR FOR THE TAF PERIOD WITH SOME MID CLOUDS. WINDS WILL
BE A LITTLE GUSTY FROM MID MORNING THROUGH MID AFTERNOON. IN THE
MEANTIME THE LOW LEVEL WINDS ARE INCREASING AND LOW LEVEL WIND
SHEAR IS POSSIBLE MAINLY NEAR TOLEDO...ELSEWHERE THE WINDS WILL BE
JUST BELOW LOW LEVEL WIND SHEAR CRITERIA. ONCE THE WINDS BECOME
GUSTY THE THREAT WILL BE MAINLY MECHANICAL TURBULENCE.
OVERNIGHT JUST SOME HIGH CLOUDS WITH MID AND LOWER CLOUDS...VFR
STARTING TO MOVE IN FROM THE SOUTH BY DAYBREAK.
.OUTLOOK...FREQUENT PERIODS OF NON VFR CONDITIONS MONDAY
AFTERNOON THROUGH THURSDAY.
&&
.MARINE...
A FRONTAL BOUNDARY WILL BE THE WEATHER FACTOR FOR THE LAKE FOR TODAY
AND THE UPCOMING WEEK. EARLY SUNDAY MORNING THE BOUNDARY WAS LOCATED
FROM SOUTHERN WISCONSIN ACROSS THE NORTHERN PORTION OF LAKE ERIE
INTO NEW YORK STATE. THE FRONTAL BOUNDARY WILL WIGGLE THROUGH MONDAY
NIGHT. FOR THE MOST PART THE WINDS WILL BE LIGHT LESS THAN 15 KNOTS
WITH VARYING WIND DIRECTIONS DEPENDING ON WHERE THE FRONTAL BOUNDARY
IS LOCATED.
FOR TUESDAY THROUGH WEDNESDAY NIGHT THE FRONTAL BOUNDARY MOVES SOUTH
OF THE LAKE AND THE WINDS BECOME NORTHEAST. THE WINDS COULD BE
STRONG ENOUGH TO NEED A SMALL CRAFT ADVISORY ON THE WEST END. FOR
THURSDAY THROUGH FRIDAY THE BOUNDARY MOVES NORTH AND THE WINDS ON
THE LAKE WILL BECOME SOUTHERLY. THEY WILL BE STRONG BUT SINCE IT IS
WARM ADVECTION THE STRONGEST WINDS WILL NOT REACH THE LAKE
SURFACE...HOWEVER...THE SPEEDS COULD BE 15 TO 25 KNOTS PROMPTING THE
NEED FOR A SMALL CRAFT ADVISORY. THIS WILL HAVE TO BE WATCHED.
THE ICE IS GONE ON THE WEST END OF THE LAKE AND WILL CONTINUE TO
MELT ON THE EAST END. THE NORTHEAST WINDS THAT ARE EXPECTED BY MID
WEEK WILL ALSO HELP IN THIS PROCESS AS WILL THE SOUTHERLY WINDS.
MUCH OF THE ICE COULD BE GONE OVER MUCH OF LAKE ERIE EXCEPT THE
EXTREME EAST END BY LATE THIS WEEK.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DJB
NEAR TERM...DJB/TK
SHORT TERM...DJB
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS NORMAN OK
714 PM CDT MON APR 6 2015
.UPDATE...
UPDATE TEMPS... WEATHER...
&&
.DISCUSSION...
ADJUSTED ISOLATED THUNDER TO A MORE CONFINED AREA OF CENTRAL TO
SWRN OK TO WRN N TX IN ACCORDANCE WITH THE SIGNIFICANT CLOUD COVER
AND SPORADIC CUMULUS THAT HAS DEVELOPED ALONG THE DRY LINE SWRN
OK. THE CHANCE FOR A FEW ISOLATED STORMS CANNOT BE RULED OUT
THROUGH SUNSET... BUT THE CHANCE REMAINS VERY LOW.
ADJUSTED TEMPS... BRINING THEM BACK IN LINE WITH OBS TREND AS
CURRENT FORECAST WAS RUNNING A TAD COOLER ACROSS WRN OK...
CONSIDERING THERE IS STILL UPPER 80S AND LOWER 90S IN THE TX
PANHANDLE.
JTK
&&
.PREV DISCUSSION... /ISSUED 656 PM CDT MON APR 6 2015/
AVIATION...07/00Z TAF ISSUANCE...
CEILINGS WILL BE THE PRIMARY FORECAST CONCERN OVERNIGHT WITH SOME
LIGHT BR/LOW CEILINGS ACROSS PORTIONS OF CENTRAL OK INTO SRN OK
NEAR DAY BREAK. WINDS WILL REMAIN OUT OF THE S/SW... GUSTY THROUGH
THE EVENING... 20 TO 25KTS... WITH WINDS RELAXING ON SLIGHTLY
OVERNIGHT... BUT REMAINING BREEZY. CEILINGS AT SITES ACROSS
CENTRAL INTO SW OK INTO WRN N TX MAY DIP TO MVFR FOR A FEW HOURS
OVERNIGHT. SOUTHERLY WINDS WILL INCREASE THROUGH NOON TOMORROW...
GUSTING 20 TO 25 KTS ONCE AGAIN.
JTK
PREV DISCUSSION... /ISSUED 336 PM CDT MON APR 6 2015/
DISCUSSION...
CONVECTION...
THE HRRR AND RAP HAVE SHOWN A RELATIVELY CONSISTENT SIGNAL OF
ISOLATED STORM/S/ DEVELOPING IN THE SOUTHWEST LATE THIS AFTERNOON.
MESOANALYSIS SHOW CONVECTIVE INHIBITION DECEASING ACROSS NORTHWEST
TEXAS. IT IS NOT A SURE THING THAT ANY STORM WILL DEVELOP AND
COVERAGE WILL BE LIMITED IF STORMS DO DEVELOP. BUT THERMODYNAMIC
PROFILE SHOWS QUITE AN UNSTABLE ATMOSPHERE... SO SEVERE WEATHER
WOULD BE LIKELY IF A STORM DOES INDEED DEVELOP. WILL KEEP POPS
BELOW 20 BUT ADD ISOLATED THUNDER IN THE WEATHER GRIDS IN TO COVER
THE POTENTIAL DEVELOPMENT. MUCH THE SAME SCENARIO IS EXPECTED
TOMORROW WITH AN UNSTABLE BUT GENERALLY CAPPED ATMOSPHERE WITHOUT
SIGNIFICANT FORCING... BUT CONVECTIVE INHIBITION DECREASES ENOUGH
THAT ISOLATED STORMS ARE POSSIBLE AGAIN IN THE LATE AFTERNOON AND
EARLY EVENING.
WEDNESDAY STILL LOOKS TO HAVE A MORE SIGNIFICANT SEVERE WEATHER
POTENTIAL AS THE TROUGH THAT IS CURRENTLY LOCATED OFF THE PACIFIC
COAST MOVES TOWARD THE HIGH PLAINS. WE EXPECT STORMS TO DEVELOP
WEDNESDAY AFTERNOON OR EVENING NEAR THE DRYLINE AND SPREAD EAST
WITH A DECENT CHANCE OF SEVERE WEATHER. THE STORM CHANCES WILL
LINGER INTO THURSDAY IN THE SOUTHEAST UNTIL THE SURFACE FRONT
MOVES THROUGH.
AFTER A BRIEF RESPITE FRIDAY...ANOTHER UPPER TROUGH APPROACHES
THIS WEEKEND INCREASING STORM CHANCES AGAIN THIS WEEKEND. EVEN AS
THE FIRST TROUGH MOVES BY THE PLAINS... THE MEAN TROUGH WILL
PERSIST IN THE WEST ALLOWING CONTINUED STORM CHANCES THROUGH
MONDAY.
FIRE WEATHER...
GUSTY POST-DRYLINE WINDS HAVE SPREAD INTO NORTHWESTERN OKLAHOMA
ALONG WITH TEMPERATURES IN THE LOWER 90S AND HUMIDITY IN THE
SINGLE DIGITS AND TEENS.... SO THE CURRENT RED FLAG WARNING LOOKS
GOOD INTO THE EARLY EVENING. ALTHOUGH WE WILL HAVE THE HEAT AND
LOW HUMIDITY AGAIN TOMORROW... WINDS ARE EXPECTED TO BE LIGHTER.
WINDS LOOK HIGHER AGAIN ON WEDNESDAY SO THE FIRE WEATHER WATCH IS
STILL VALID.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 65 84 66 82 / 10 20 20 30
HOBART OK 60 87 64 86 / 10 10 10 20
WICHITA FALLS TX 66 87 66 88 / 10 20 10 30
GAGE OK 53 88 53 85 / 10 0 10 10
PONCA CITY OK 63 87 64 85 / 10 20 20 40
DURANT OK 68 80 68 81 / 10 10 10 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR OKZ004-005-009-
010-014>016-021-033-034.
FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR OKZ004>006-009>011-014>016-021-022-033>037.
TX...FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR TXZ083>085-087-088.
&&
$$
99/99
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
656 PM CDT MON APR 6 2015
.AVIATION...07/00Z TAF ISSUANCE...
CEILINGS WILL BE THE PRIMARY FORECAST CONCERN OVERNIGHT WITH SOME
LIGHT BR/LOW CEILINGS ACROSS PORTIONS OF CENTRAL OK INTO SRN OK
NEAR DAY BREAK. WINDS WILL REMAIN OUT OF THE S/SW... GUSTY THROUGH
THE EVENING... 20 TO 25KTS... WITH WINDS RELAXING ON SLIGHTLY
OVERNIGHT... BUT REMAINING BREEZY. CEILINGS AT SITES ACROSS
CENTRAL INTO SW OK INTO WRN N TX MAY DIP TO MVFR FOR A FEW HOURS
OVERNIGHT. SOUTHERLY WINDS WILL INCREASE THROUGH NOON TOMORROW...
GUSTING 20 TO 25 KTS ONCE AGAIN.
JTK
&&
.PREV DISCUSSION... /ISSUED 336 PM CDT MON APR 6 2015/
DISCUSSION...
CONVECTION...
THE HRRR AND RAP HAVE SHOWN A RELATIVELY CONSISTENT SIGNAL OF
ISOLATED STORM/S/ DEVELOPING IN THE SOUTHWEST LATE THIS AFTERNOON.
MESOANALYSIS SHOW CONVECTIVE INHIBITION DECEASING ACROSS NORTHWEST
TEXAS. IT IS NOT A SURE THING THAT ANY STORM WILL DEVELOP AND
COVERAGE WILL BE LIMITED IF STORMS DO DEVELOP. BUT THERMODYNAMIC
PROFILE SHOWS QUITE AN UNSTABLE ATMOSPHERE... SO SEVERE WEATHER
WOULD BE LIKELY IF A STORM DOES INDEED DEVELOP. WILL KEEP POPS
BELOW 20 BUT ADD ISOLATED THUNDER IN THE WEATHER GRIDS IN TO COVER
THE POTENTIAL DEVELOPMENT. MUCH THE SAME SCENARIO IS EXPECTED
TOMORROW WITH AN UNSTABLE BUT GENERALLY CAPPED ATMOSPHERE WITHOUT
SIGNIFICANT FORCING... BUT CONVECTIVE INHIBITION DECREASES ENOUGH
THAT ISOLATED STORMS ARE POSSIBLE AGAIN IN THE LATE AFTERNOON AND
EARLY EVENING.
WEDNESDAY STILL LOOKS TO HAVE A MORE SIGNIFICANT SEVERE WEATHER
POTENTIAL AS THE TROUGH THAT IS CURRENTLY LOCATED OFF THE PACIFIC
COAST MOVES TOWARD THE HIGH PLAINS. WE EXPECT STORMS TO DEVELOP
WEDNESDAY AFTERNOON OR EVENING NEAR THE DRYLINE AND SPREAD EAST
WITH A DECENT CHANCE OF SEVERE WEATHER. THE STORM CHANCES WILL
LINGER INTO THURSDAY IN THE SOUTHEAST UNTIL THE SURFACE FRONT
MOVES THROUGH.
AFTER A BRIEF RESPITE FRIDAY...ANOTHER UPPER TROUGH APPROACHES
THIS WEEKEND INCREASING STORM CHANCES AGAIN THIS WEEKEND. EVEN AS
THE FIRST TROUGH MOVES BY THE PLAINS... THE MEAN TROUGH WILL
PERSIST IN THE WEST ALLOWING CONTINUED STORM CHANCES THROUGH
MONDAY.
FIRE WEATHER...
GUSTY POST-DRYLINE WINDS HAVE SPREAD INTO NORTHWESTERN OKLAHOMA
ALONG WITH TEMPERATURES IN THE LOWER 90S AND HUMIDITY IN THE
SINGLE DIGITS AND TEENS.... SO THE CURRENT RED FLAG WARNING LOOKS
GOOD INTO THE EARLY EVENING. ALTHOUGH WE WILL HAVE THE HEAT AND
LOW HUMIDITY AGAIN TOMORROW... WINDS ARE EXPECTED TO BE LIGHTER.
WINDS LOOK HIGHER AGAIN ON WEDNESDAY SO THE FIRE WEATHER WATCH IS
STILL VALID.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 83 63 84 66 / 10 10 20 20
HOBART OK 88 58 87 64 / 10 10 10 10
WICHITA FALLS TX 88 64 87 66 / 10 10 20 10
GAGE OK 92 51 88 53 / 10 10 0 10
PONCA CITY OK 84 61 87 64 / 10 10 20 20
DURANT OK 79 67 80 68 / 20 10 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR OKZ004-005-009-
010-014>016-021-033-034.
FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR OKZ004>006-009>011-014>016-021-022-033>037.
TX...FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR TXZ083>085-087-088.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
1001 PM CDT MON APR 6 2015
.DISCUSSION...NO MAJOR CHANGES TO THE FORECAST ANTICIPATED THIS
EVENING. DID UPDATE FORECAST TO ACCOUNT FOR LATEST OBSERVATIONAL
TRENDS. 00Z DRT/CRP SHOW DECENT CAP IN PLACE SO THINK MOUNTAIN
CONVECTION WILL HAVE A DIFFICULT TIME MAKING IT EASTWARD INTO THE
AREA. WILL KEEP POPS BELOW MENTIONABLE LEVELS FOR THE REMAINDER OF
THE NIGHT. HOWEVER...OF NOTE..LATEST RUNS OF THE HRRR BRING
CONVECTION ACROSS THE RIO GRANDE PLAINS. WILL CONTINUE TO MONITOR
THOUGH.
&&
.PREV DISCUSSION... /ISSUED 700 PM CDT MON APR 6 2015/
DISCUSSION...UPDATED FOR THE 00Z AVIATION DISCUSSION.
AVIATION...VFR CONDITIONS SHOULD LAST FOR THE NEXT FEW
HOURS...WITH CIGS EXPECTED TO LOWER TO MVFR TO IFR OVERNIGHT.
GUSTY WINDS WILL ALSO BEGIN TO DECOUPLE THIS EVENING...BECOMING
S-LY AROUND 10 KNOTS OVERNIGHT...WITH THE EXCEPTION OF LRD KEEPING
A MORE S-SE-LY FLOW. THIS DECOUPLING WILL LEAD TO STRONGER S-LY
FLOW ABOVE THE SFC WITH A 25-30 KT LLJ DEVELOPING ACROSS THE
COASTAL PLAINS. THE STRENGTH AND DIRECTION OF THE SFC WIND SHOULD
HOLD OFF ANY MENTION OF LLWS. THIS LLJ SHOULD AIDE IN RAISING CIGS
LATE IN THE NIGHT...WITH PREVAILING MVFR BY AND AFTER 10Z. WINDS
WILL BEGIN TO MIX DOWN MID MORNING WITH CIGS SLOWLY RISING. VFR
CONDITIONS WITH WINDS SHIFTING OUT OF THE SE ARE EXPECTED BY THE
AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 71 85 72 83 72 / 10 10 10 10 10
VICTORIA 69 84 70 83 71 / 10 10 10 10 10
LAREDO 71 91 71 91 71 / 10 10 10 10 10
ALICE 70 89 70 87 71 / 10 10 10 10 10
ROCKPORT 71 81 71 79 72 / 10 10 10 10 10
COTULLA 68 88 69 89 69 / 10 10 10 10 10
KINGSVILLE 70 87 71 86 72 / 10 10 10 10 10
NAVY CORPUS 71 83 72 79 72 / 10 10 10 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
TB/78...SHORT TERM
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
934 PM CDT MON APR 6 2015
.UPDATE...
LATE AFTERNOON/EARLY EVENING STORMS OUT OF THE NORTHEAST MEXICAN
MOUNTAINS DISSIPATED AS THEY WERE MOVING EAST AND INTO A CAPPED
REGION. MOST OF THE HIRES AND MEDIUM RANGE GUIDANCE ARE KEEPING
THE AREA DRY OVERNIGHT WITH THE EXCEPTION OF LATEST HRRR AND RAPIP
REFRESH WHICH BRING ISOLATED STORMS ACROSS THE RIO GRANDE PLAINS
OVERNIGHT. AT THIS TIME...WILL GO WITH A DRY FORECAST AFTER
MIDNIGHT AS SUGGESTED BY THE MAJORITY OF THE MODEL SOLUTIONS.
ALSO...ADJUSTED TONIGHT`S TEMPS BASED ON CURRENT TRENDS AND MAV
GUIDANCE.
&&
.PREV DISCUSSION... /ISSUED 604 PM CDT MON APR 6 2015/
AVIATION...
VFR IS CURRENTLY PREVAILING AT ALL SITES AT THE PRESENT HOUR.
HOWEVER...DETERIORATING CONDITIONS CAN BE EXPECTED ONCE AGAIN
AFTER SUNSET WITH MVFR RETURNING BY 04-05Z. CEILINGS WILL LOWER
EVEN FURTHER TO IFR BY 9Z. LIFR IS ALSO POSSIBLE BUT WILL KEEP
THINGS IFR FOR NOW. CONDITIONS WILL IMPROVE BACK TO MVFR AROUND
17Z...THEN VFR A COUPLE OF HOURS LATER. CONVECTION WEST OF THE RIO
GRANDE IS NOT EXPECTED TO IMPACT KDRT DUE TO A STRONG CAPPING
INVERSION.
HAMPSHIRE
PREV DISCUSSION... /ISSUED 321 PM CDT MON APR 6 2015/
SHORT TERM (TONIGHT THROUGH TUESDAY NIGHT)...
THE AFTERNOON VISIBLE SATELLITE IMAGERY STILL SHOWS PLENTY OF CLOUD
COVER IN PLACE ACROSS SOUTH CENTRAL TEXAS. THIS WILL LIMIT THE
OVERALL INSTABILITY AND LIKELY ALLOW THE MID-LEVEL CAPPING
INVERSION TO KEEP CONVECTION FROM DEVELOPING ACROSS MOST AREAS
THROUGH EARLY THIS EVENING. THE ONE EXCEPTION WILL BE OUT WEST
ACROSS THE SOUTHERN EDWARDS PLATEAU AND RIO GRANDE PLAINS. SPC
MESOANALYSIS SHOWS A NARROW AXIS OF SURFACE-BASED CAPE ALONG WITH
A LOCALIZED MIN IN CONVECTIVE INHIBITION. THE HRRR CONTINUES TO
SUGGEST THE POTENTIAL FOR SHOWERS AND THUNDERSTORMS TO DEVELOP
NEAR THE SERRANIAS DEL BURRO MOUNTAINS...THEN MOVE EAST INTO THE
RIO GRANDE PLAINS. IF CONVECTION DOES MANAGE TO DEVELOP...A STRONG
STORM OR TWO REMAINS POSSIBLE WITH HAIL AND GUSTY WINDS BEING THE
MAIN THREATS. WARM AND DRY CONDITIONS ARE EXPECTED ON TUESDAY AS
SOUTHWESTERLY FLOW ALOFT REMAINS INTACT.
LONG TERM (WEDNESDAY THROUGH MONDAY)...
ON WEDNESDAY...SOUTHWEST FLOW ALOFT WILL CONTINUE ACROSS THE REGION. AN
INCREASE IN MID-LEVEL SHORTWAVE ACTIVITY COULD LEAD TO AN UPTICK IN
PRECIPITATION CHANCES ACROSS MOST AREAS LATE WEDNESDAY INTO EARLY
THURSDAY. A FEW STRONG TO SEVERE STORMS REMAIN POSSIBLE ACROSS THE
SOUTHERN EDWARDS PLATEAU AND NORTHWEST HILL COUNTRY DURING THE LATE
AFTERNOON AND EVENING HOURS. FOR THE REMAINDER OF THE WORK WEEK AND
UPCOMING WEEKEND...SOUTHWEST FLOW ALOFT CONTINUES AND BECOMES
INCREASINGLY ACTIVE. WE/LL CONTINUE TO MENTION A LOW CHANCE FOR SHOWERS
AND THUNDERSTORMS ACROSS MOST AREAS. THE MEDIUM RANGE MODELS SHOW A
STRONGER UPPER LEVEL TROUGH MOVING IN FROM THE WEST THIS WEEKEND.
THERE ARE SOME TIMING DIFFERENCES AND WILL AWAIT ADDITIONAL MODEL
RUNS BEFORE ADJUSTING THE CURRENT FORECAST.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 68 84 69 84 68 / 10 10 10 10 10
AUSTIN BERGSTROM INTL AIRPORT 67 83 68 83 68 / 10 10 10 10 10
NEW BRAUNFELS MUNI AIRPORT 67 85 67 85 68 / 10 10 10 10 10
BURNET MUNI AIRPORT 67 84 66 83 66 / 10 10 10 10 20
DEL RIO INTL AIRPORT 69 87 69 88 68 / 20 10 10 10 30
GEORGETOWN MUNI AIRPORT 68 83 68 83 68 / 10 10 10 10 20
HONDO MUNI AIRPORT 68 84 68 86 68 / 10 10 - 10 10
SAN MARCOS MUNI AIRPORT 67 84 68 83 68 / 10 10 10 10 10
LA GRANGE - FAYETTE REGIONAL 69 84 70 83 71 / 10 10 10 10 10
SAN ANTONIO INTL AIRPORT 68 84 69 84 69 / 10 10 10 10 10
STINSON MUNI AIRPORT 68 84 68 85 69 / 10 10 10 10 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...29
SYNOPTIC/GRIDS...17
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
326 PM CDT Sun Apr 5 2015
.SHORT TERM...
(Tonight and Tomorrow)
Main concern with this package is with the threat for a few
thunderstorms across Crockett County tonight and areas to the
east.
A couple of storms have formed in the Davis Mountains and they are
moving east. The models did show a jet max moving across West Texas
tonight, placing WC TX in the favored right rear entrance region.
This upper level jet max combined with the increasing low level jet
could sustain convection tonight. Although the latest HRRR run
progged a large area of convection moving into the southern half of
WC TX overnight, still have low confidence since all of the other
models showed nothing. Will continue slight chance Pops for
thunderstorms mainly across Crockett County tonight. If this
convection persists, the Pops may have to be adjusted east and
northeast.
Expect the low clouds across the east to slowly erode through the
early evening. With plenty of low level gulf moisture across the
region, expect low clouds to develop overnight.
As the low clouds burn off tomorrow afternoon, temperatures will
quickly warm mostly into the mid and upper 80s. The models show the
dryline setting up west of Crockett County across the Trans Pecos
region. Model soundings show a strong cap through 6 PM tomorrow and
this should keep any convection from forming.
26
.LONG TERM...
(Tomorrow night through Sunday)
The main concern through the extended forecast is the potential for
showers and thunderstorms Wednesday, and toward the latter part of
the week for much of West Central Texas. Monday afternoon/evening
the dryline will set up across our western border. Showers and
thunderstorms may develop during the evening hours, mainly across
the Trans Pecos region of West Texas. A few of these storms may
drift into mainly Crockett County during the evening hours, where
slight chance PoPs are included. On Tuesday, the dryline will once
again move east to about our western boundary, during the late
afternoon/early evening. At this time, the cap looks to dominate,
with little to no convection developing. An isolated thunderstorms
will be possible if we are able to break the cap, but the forecast
was kept dry for now.
Models are in fairly good agreement showing the next upper level
low/trough centered across Utah/Colorado on Wednesday, then tracking
across the Central Plains Thursday. Ahead of this feature, a dryline
is forecast to move east to near our western border late Wednesday
afternoon/evening. Enough afternoon heating (highs in the mid 80s to
low 90s) and lift from the upper level trough should allow for the
development of isolated to scattered showers and thunderstorms,
mainly during the late afternoon/evening, then moving across the
area overnight. The ECMWF continues to be much drier than both the
GFS/Canadian, but geared the forecast closer to the wetter GFS. A
fairly unstable atmosphere will lie along and ahead of the dryline,
with SBCAPE values generally in the 1500-2500 J/KG range and 0-6 KM
shear values in the 35 to 50 knot range. Strong to severe
thunderstorms will be possible, with large hail and damaging winds
being the main hazards at this time.
With the passage of the upper level trough, a cold front will move
through West Central Texas on Thursday. Slightly cooler temperatures
are forecast Thursday into the weekend, with highs generally in the
mid 70s to low 80s. The next upper level low across the Pacific
Ocean will then begin to approach California, with West Central
Texas in southwest flow aloft. Intermittent disturbances may result
in isolated to scattered showers and thunderstorms, Friday into next
weekend, and this is reflected in the grids. The aforementioned
upper level low will eventually tack across West Texas or New
Mexico, which may bring an increasing chance of showers and
thunderstorms for late in the weekend or early next week.
Daniels
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 65 88 66 89 66 / 10 10 10 10 10
San Angelo 64 87 66 89 66 / 10 5 10 10 10
Junction 66 83 68 84 66 / 10 10 10 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
26/Daniels
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
109 PM CDT SUN APR 5 2015
.AVIATION...
/18Z TAFS/
CIGS WILL GRADUALLY LIFT THIS AFTERNOON AS A POORLY DEFINED WARM
FRONT SLOWLY MOVES NORTH AND EAST. DRT IS ALREADY AT MVFR AND HAVE
DECENT CONFIDENCE THAT SAT/SSF WILL LIFT TO MVFR BTWN 19-20Z...WITH
ALL THREE SITES LIFTING TO VFR BY 21Z. CONFIDENCE IS LOWER AT AUS
WHERE LIGHT LIFR CIGS AND DRIZZLE ARE ONGOING FURTHER NORTH...SO
EXPECT LIFR/IFR CIGS TO CONTINUE THROUGH 21Z AND MVFR AFTERWARDS.
MAIN FORECAST ISSUE FOR TONIGHT IS WHETHER A WEAK MCS WILL MOVE IN
FROM BIG BEND AND AFFECT DRT BETWEEN 03-06Z AS HRRR AND NAM BOTH
SUGGEST...BUT CONFIDENCE IS TOO LOW TO INCLUDE TSTMS AT THIS TIME.
OTHERWISE...EXPECT LOW CLOUDS TO DEVELOP ALONG THE ESCARPMENT
BTWN 03-06Z TONIGHT...LEADING TO IFR CIGS AT SAT/SSF/AUS BY 06Z.
DRT CIGS WILL BE DEPENDENT ON MCS BEFORE FALLING TO MVFR TONIGHT.
LH
&&
.PREV DISCUSSION... /ISSUED 936 AM CDT SUN APR 5 2015/
UPDATE...UPDATES THIS MORNING TO ADD AREAS OF FOG THROUGH THE
MORNING FOR PORTIONS OF THE HILL COUNTRY AND I-35 CORRIDOR EAST AS
WELL AS AREAS OF DRIZZLE ALONG THE EDGE OF THE ESCARPMENT
EASTWARD. OVERALL RADAR TRENDS AND RELIABLE GUIDANCE SUGGESTS
CONVECTIVE ACTIVITY WILL REMAIN LIMITED AND REMOVED MENTION OF
THUNDER TODAY. MINOR ADJUSTMENTS MADE TO TEMPS FOR TODAY.
PREV DISCUSSION... /ISSUED 700 AM CDT SUN APR 5 2015/
UPDATE...
AS NOTED IN THE AVIATION DISCUSSION BELOW...CONDITIONS CONTINUE TO
LOOK INCREASINGLY STABLE ON BOTH RADAR AND RADAR DERIVED WIND
PATTERNS. HI-RES MODEL SOLUTIONS STILL SHOW SOME LIGHT RAINS
POSSIBLE OVER CENTRAL TX AND THE COASTAL PRAIRIES...BUT UNIFORM
WINDS AND A PROBABLE CAPPING INVERSION WOULD SUGGEST JUST A FEW
SPRINKLES. A FEW THUNDERSTORMS ARE STILL ACCOUNTED FOR IN THE
AFTERNOON HOURS...AS THE ABSENCE OF A FRONT COULD ALLOW FOR ADDED
SUNSHINE AND ENHANCE AREAS OF DIFFERENTIAL HEATING.
PREV DISCUSSION... /ISSUED 647 AM CDT SUN APR 5 2015/
AVIATION...
EXPECT IFR CEILINGS ALONG WITH SOME REDUCED VISBYS ALONG THE
SAT/SSF/AUS SITES THROUGH THE MORNING HOURS. CLOUD DECKS HAVE BEEN
GOING DOWN THE PAST FEW HOURS WHILE SAT IS NOW REPORTING SOME
LIGHT RAIN/DRIZZLE. AUS SHOULD GO IFR OVER THE NEXT COUPLE OF
HOURS WHILE DRT HAS BEEN HANGING NEAR 3000FT. AM BRINGING DRT
DOWN TO MVFR BUT BY AFTERNOON THE HRRR IS SHOWING WESTERN AREAS TO
GET TO VFR. BECAUSE THE GFS/NAM HAVE BEEN WAY OVERDOING THE RAIN
THIS MORNING...FEEL THAT THE HRRR HAS A BETTER FEEL. I ALSO BRING
SAT/SSF INTO VFR BY LATE IN THE DAY AS BATCH OF MOISTURE AND LIFT
MOVE NE OF THE AREA. LOOKS LIKE ALL SITES WILL RETURN TO MVFR BY
MONDAY MORNING AS THE LOW LEVEL JET STRENGTHENS. HAVE REMOVED MOST
OF THE MENTION OF PRECIP FOR TODAY AS THE RAIN HAS NOT
MATERIALIZED.
PREV DISCUSSION... /ISSUED 349 AM CDT SUN APR 5 2015/
SHORT TERM (TODAY THROUGH MONDAY)...
WEAK FRONTAL INVERSION IS MOSTLY WASHED AWAY...LEAVING A REDUCED
POTENTIAL FOR OVERRUNNING RAIN AND THUNDERSTORMS. A FEW NEW
CLUSTERS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TO REDEVELOP
OVER AREAS ALONG AND EAST OF I-35 THROUGH THIS MORNING...BUT MOST
OF THE RAINS ARE LIGHT SPRINKLES OF A TRACE TO A FEW HUNDREDTHS OF
AN INCH. PLAN VIEW PLOTS OF THE VAD WINDS SHOW THE WINDS ABOVE THE
BOUNDARY LAYER ARE TURNING S TO SW OVER THE WEST AND CENTRAL
TX...SO THE LAYER OF CLOUDINESS SHOULD BEGIN TO BREAK UP LATER
TODAY WITH TEMPERATURES REBOUNDING BACK TO NORMALS.
OVER W TX...SPC HAS INDICATED A MARGINAL RISK OF SEVERE WEATHER
TRIGGERED OFF HIGHER TERRAIN AND A DRY-LINE. A FEW STORMS COULD
MOVE INTO VAL VERDE COUNTY...BUT SHOULD WEAKEN WHEN MOVING INTO AN
INCREASINGLY CAPPED ENVIRONMENT. WARMER TEMPERATURES TODAY INTO
MONDAY COULD FURTHER INCREASE DRY-LINE ACTIVITY OVER W TX LATE
MONDAY AS THE WIND FLOW IN THE MID LEVELS REMAINS MOSTLY ZONAL AND
LOW LEVEL MOISTURE DEEPENS OVER THE SOUTHERN EDWARDS PLATEAU.
LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...
ALOFT A LOW AMPLITUDE RIDGE MAINTAINS A ZONAL AND SLIGHTLY SWLY
FLOW ALOFT...WHICH IS TYPICALLY A BREEZY AND STABLE PATTERN FOR
THIS AREA. HOWEVER...MODEL CONSENSUS POPULATION OF POPS SUGGESTS A
GOOD POTENTIAL FOR WESTERLY SHORTWAVE ACTIVITY TO MOVE INTO THIS
STABLE PATTERN FOR DAILY ROUNDS OF DRY-LINE ACTIVITY OVER MAINLY
WESTERN AREAS WEDNESDAY...AND A NEWD EJECTION OF AN UPPER LOW
PASSING TO THE NW HELPING TO DRIVE THE SHORTWAVE EAST INTO CENTRAL
TX THURSDAY INTO FRIDAY. THE CURRENT BELIEF IS THAT THIS PATTERN
IS A BIT BULLISH...AND A SLIGHT LEAN TO THE DRIER ECMWF AND
CANADIAN MODELS IS FAVORED OVER A MUCH STORMIER GFS. IF THE DRIER
SOLUTIONS WIN OUT...MUCH OF THE AREA COULD CONTINUE TO DRY OUT AND
LEAD TO A WARMING TREND IN EXTENDED PERIOD TEMPERATURE FORECASTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 68 65 82 66 84 / 20 10 10 10 -
AUSTIN BERGSTROM INTL AIRPORT 70 64 80 66 83 / 20 10 10 10 10
NEW BRAUNFELS MUNI AIRPORT 73 66 83 66 84 / 20 10 10 10 -
BURNET MUNI AIRPORT 66 64 81 65 83 / 20 10 - 10 -
DEL RIO INTL AIRPORT 77 65 87 68 87 / 20 20 10 10 10
GEORGETOWN MUNI AIRPORT 65 65 81 67 83 / 20 10 - - -
HONDO MUNI AIRPORT 73 65 81 66 84 / 20 10 10 - -
SAN MARCOS MUNI AIRPORT 72 65 82 66 84 / 20 10 10 10 10
LA GRANGE - FAYETTE REGIONAL 75 68 81 68 82 / 20 10 - - 10
SAN ANTONIO INTL AIRPORT 73 66 81 67 83 / 20 10 10 10 -
STINSON MUNI AIRPORT 75 66 81 67 85 / 20 10 10 10 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...00
SYNOPTIC/GRIDS...76
PUBLIC SERVICE/DATA COLLECTION...12
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1053 AM CDT SUN APR 5 2015
.UPDATE...
MORNING FORECAST UPDATE...
&&
.DISCUSSION...
FIRST ROUND OF CONVECTION HAS MOVED ACROSS NORTHERN PORTIONS OF
SE TX THIS MORNING AND NOW NE OF THE AREA OVER THE ARKLATEX INTO E
TX. WATER VAPOR IMAGERY SHOWS SHORTWAVE TROUGH MOVING TOWARDS N
TX. UPPER LEVEL ANALYSIS SHOWS A JET STREAK MOVING INTO THE S
PLAINS WITH SHOULD CONTINUE TO SUPPORT THUNDERSTORM CHANCES. WATER
VAPOR IMGERY ALSO SHOWING POSSIBLY ANOTHER WEAK WAVE MOVING INTO S
TX. AT THE SFC...WARM FRONT WAS BARELY PUSHING ONSHORE THE MIDDLE
TX COAST AND ISENTROPIC LIFT OVER THE FRONT WAS KEEPING CLOUDS AND
LIGHT RAIN IN PLACE FOR THE COASTAL AREAS. SFC DEWPOINTS HAVING
COME UP INTO THE 70S ALONG THE COAST WITH 50S FARTHER INLAND. MAIN
FORECAST ISSUE WILL BE TEMPS TODAY AS WARM FRONT PUSHES NORTH. A
LOT OF THE MESOSCALE MODELS SLOWLY PUSH THE WARM FRONT NORTH SO
THERE WILL BE A GOOD TEMP GRADIENT ACROSS THE AREA FOR MAX TEMPS.
COASTAL AREAS COULD REACH THE MID 70S WITH LOW 60S TOWARDS
CROCKETT. UPDATED THE FORECAST FOR THESE TRENDS. STILL MENTIONED
THUNDERSTORMS WITH SHORT WAVE TROUGH OVER S TX POSSIBLY MOVING
OVER THE REGION TO ENHANCE LIFT.
39
&&
.PREV DISCUSSION... /ISSUED 708 AM CDT SUN APR 5 2015/
AVIATION...
THE FIRST ROUND OF SHOWERS AND THUNDERSTORMS ARE NOW EXITING
NORTHEAST WITH A THIN LINE OF -RA/-DZ PASSING ACROSS THE CITY
AT THIS HOUR. THE NEXT SHORTWAVE DISTURBANCE IS TRAVELING OUT OF
THE LOWER RIO GRANDE THIS MORNING AND IS TIMED TO REACH THE REGION
EARLY THIS AFTERNOON. ANTICIPATING WIDELY SCATTERED SHOWERS (MAYBE
AN ISOLATED STORM) TO AFFECT SE TX FROM EARLY AFTERNOON THROUGH
AROUND SUNSET. RETURN FLOW WILL INCREASE MOISTURE LEVELS AND A
VICINITY WARM FRONTAL BOUNDARY SNEAKING INTO THE COASTAL BEND WILL
BOTH BE REASONS TO LOWER CEILINGS INTO MVFR. EARLY EVENING COOLING
SURFACE SHOULD MAKE FOR CONDUCIVE CONDITIONS FOR THE FURTHER LOWERING
OF OVERCAST INTO LATE EVENING/EARLY MORNING IFR. 31
PREV DISCUSSION... /ISSUED 421 AM CDT SUN APR 5 2015/
DISCUSSION...
AREAS OF RAIN WITH EMBEDDED SHOWERS AND THUNDERSTORMS ARE FOUND ACROSS
OUR NORTHERN AND WESTERN COUNTIES EARLY THIS MORNING. ANTICIPATE ACTIVITY
TO FILL IN ACROSS MUCH OF THE AREA OVER THE NEXT SEVERAL HOURS AS A
DISTURBANCE IN THE SOUTHWEST FLOW ALOFT MOVES ACROSS THE STATE. IF THE
LATEST HRRR IS CORRECT...BEST RAIN CHANCES AND HIGHEST RAINFALL AMOUNTS
WILL END UP BEING GENERALLY ALONG/NORTH OF INTERSTATE 10. RAINS WILL
COME TO AN END FROM WEST TO EAST AS THE DAY PROGRESSES...AND IT STILL
LOOKS LIKE THE FIRST COUPLE DAYS OF THE UPCOMING WEEK WILL BE WARM AND
DRY WITH FALLING PRECIPITABLE WATER VALUES. AS WE HEAD INTO THE END
OF THE WEEK AND ON INTO NEXT WEEKEND...RAIN CHANCES COME BACK INTO THE
FORECAST AS MOISTURE LEVELS INCREASE AND A FRONTAL BOUNDARY ENTERS THE
AREA. MODELS ARE SHOWING SOME DIFFERENCES IN THE TIMING AND STRENGTH
OF A STORM SYSTEM NEXT WEEKEND. WE`LL NEED TO WATCH HOW THINGS EVOLVE
AS SOME MODELS ARE POINTING TOWARD A POSSIBLE LINE OF STRONG/SEVERE
STORMS A WEEK FROM TODAY. 42
MARINE...
HIGH PRESSURE CENTERED OVER THE EASTERN UNITED STATES...IN RELATION
TO LOWER PLAINS PRESSURES...WILL MAINTAIN A PERSISTENT LIGHT TO
OCCASIONALLY MODERATE ONSHORE FLOW THROUGH THE UPCOMING WEEK. A
PASSING WEAK SHORTWAVE DISTURBANCE WILL HAVE SLIGHT CHANCES FOR A
BRIEF SHOWER OR ISOLATED THUNDERSTORM IN THROUGH THE DAY. AFTER
SEVERAL DAYS OF DRY WEATHER...RAIN AND STORM CHANCES WILL INCREASE
FROM THE APPROACH AND EVENTUAL PASSAGE OF THE NEXT UPPER TROUGH
NEXT WEEKEND INTO EARLY NEXT WEEK. 31
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 71 66 81 67 83 / 40 10 10 10 10
HOUSTON (IAH) 73 66 82 69 83 / 40 10 10 10 10
GALVESTON (GLS) 73 70 79 71 76 / 20 10 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...39
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
936 AM CDT SUN APR 5 2015
.UPDATE...UPDATES THIS MORNING TO ADD AREAS OF FOG THROUGH THE
MORNING FOR PORTIONS OF THE HILL COUNTRY AND I-35 CORRIDOR EAST AS
WELL AS AREAS OF DRIZZLE ALONG THE EDGE OF THE ESCARPMENT
EASTWARD. OVERALL RADAR TRENDS AND RELIABLE GUIDANCE SUGGESTS
CONVECTIVE ACTIVITY WILL REMAIN LIMITED AND REMOVED MENTION OF
THUNDER TODAY. MINOR ADJUSTMENTS MADE TO TEMPS FOR TODAY.
&&
.PREV DISCUSSION... /ISSUED 700 AM CDT SUN APR 5 2015/
UPDATE...
AS NOTED IN THE AVIATION DISCUSSION BELOW...CONDITIONS CONTINUE TO
LOOK INCREASINGLY STABLE ON BOTH RADAR AND RADAR DERIVED WIND
PATTERNS. HI-RES MODEL SOLUTIONS STILL SHOW SOME LIGHT RAINS
POSSIBLE OVER CENTRAL TX AND THE COASTAL PRAIRIES...BUT UNIFORM
WINDS AND A PROBABLE CAPPING INVERSION WOULD SUGGEST JUST A FEW
SPRINKLES. A FEW THUNDERSTORMS ARE STILL ACCOUNTED FOR IN THE
AFTERNOON HOURS...AS THE ABSENCE OF A FRONT COULD ALLOW FOR ADDED
SUNSHINE AND ENHANCE AREAS OF DIFFERENTIAL HEATING.
PREV DISCUSSION... /ISSUED 647 AM CDT SUN APR 5 2015/
AVIATION...
EXPECT IFR CEILINGS ALONG WITH SOME REDUCED VISBYS ALONG THE
SAT/SSF/AUS SITES THROUGH THE MORNING HOURS. CLOUD DECKS HAVE BEEN
GOING DOWN THE PAST FEW HOURS WHILE SAT IS NOW REPORTING SOME
LIGHT RAIN/DRIZZLE. AUS SHOULD GO IFR OVER THE NEXT COUPLE OF
HOURS WHILE DRT HAS BEEN HANGING NEAR 3000FT. AM BRINGING DRT
DOWN TO MVFR BUT BY AFTERNOON THE HRRR IS SHOWING WESTERN AREAS TO
GET TO VFR. BECAUSE THE GFS/NAM HAVE BEEN WAY OVERDOING THE RAIN
THIS MORNING...FEEL THAT THE HRRR HAS A BETTER FEEL. I ALSO BRING
SAT/SSF INTO VFR BY LATE IN THE DAY AS BATCH OF MOISTURE AND LIFT
MOVE NE OF THE AREA. LOOKS LIKE ALL SITES WILL RETURN TO MVFR BY
MONDAY MORNING AS THE LOW LEVEL JET STRENGTHENS. HAVE REMOVED MOST
OF THE MENTION OF PRECIP FOR TODAY AS THE RAIN HAS NOT
MATERIALIZED.
PREV DISCUSSION... /ISSUED 349 AM CDT SUN APR 5 2015/
SHORT TERM (TODAY THROUGH MONDAY)...
WEAK FRONTAL INVERSION IS MOSTLY WASHED AWAY...LEAVING A REDUCED
POTENTIAL FOR OVERRUNNING RAIN AND THUNDERSTORMS. A FEW NEW
CLUSTERS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TO REDEVELOP
OVER AREAS ALONG AND EAST OF I-35 THROUGH THIS MORNING...BUT MOST
OF THE RAINS ARE LIGHT SPRINKLES OF A TRACE TO A FEW HUNDREDTHS OF
AN INCH. PLAN VIEW PLOTS OF THE VAD WINDS SHOW THE WINDS ABOVE THE
BOUNDARY LAYER ARE TURNING S TO SW OVER THE WEST AND CENTRAL
TX...SO THE LAYER OF CLOUDINESS SHOULD BEGIN TO BREAK UP LATER
TODAY WITH TEMPERATURES REBOUNDING BACK TO NORMALS.
OVER W TX...SPC HAS INDICATED A MARGINAL RISK OF SEVERE WEATHER
TRIGGERED OFF HIGHER TERRAIN AND A DRY-LINE. A FEW STORMS COULD
MOVE INTO VAL VERDE COUNTY...BUT SHOULD WEAKEN WHEN MOVING INTO AN
INCREASINGLY CAPPED ENVIRONMENT. WARMER TEMPERATURES TODAY INTO
MONDAY COULD FURTHER INCREASE DRY-LINE ACTIVITY OVER W TX LATE
MONDAY AS THE WIND FLOW IN THE MID LEVELS REMAINS MOSTLY ZONAL AND
LOW LEVEL MOISTURE DEEPENS OVER THE SOUTHERN EDWARDS PLATEAU.
LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...
ALOFT A LOW AMPLITUDE RIDGE MAINTAINS A ZONAL AND SLIGHTLY SWLY
FLOW ALOFT...WHICH IS TYPICALLY A BREEZY AND STABLE PATTERN FOR
THIS AREA. HOWEVER...MODEL CONSENSUS POPULATION OF POPS SUGGESTS A
GOOD POTENTIAL FOR WESTERLY SHORTWAVE ACTIVITY TO MOVE INTO THIS
STABLE PATTERN FOR DAILY ROUNDS OF DRY-LINE ACTIVITY OVER MAINLY
WESTERN AREAS WEDNESDAY...AND A NEWD EJECTION OF AN UPPER LOW
PASSING TO THE NW HELPING TO DRIVE THE SHORTWAVE EAST INTO CENTRAL
TX THURSDAY INTO FRIDAY. THE CURRENT BELIEF IS THAT THIS PATTERN
IS A BIT BULLISH...AND A SLIGHT LEAN TO THE DRIER ECMWF AND
CANADIAN MODELS IS FAVORED OVER A MUCH STORMIER GFS. IF THE DRIER
SOLUTIONS WIN OUT...MUCH OF THE AREA COULD CONTINUE TO DRY OUT AND
LEAD TO A WARMING TREND IN EXTENDED PERIOD TEMPERATURE FORECASTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 72 66 82 66 84 / 30 10 10 10 -
AUSTIN BERGSTROM INTL AIRPORT 72 66 80 66 83 / 30 10 10 10 -
NEW BRAUNFELS MUNI AIRPORT 74 66 83 66 84 / 30 10 10 10 -
BURNET MUNI AIRPORT 71 64 81 65 83 / 20 10 10 10 -
DEL RIO INTL AIRPORT 77 65 87 68 87 / 20 20 10 20 10
GEORGETOWN MUNI AIRPORT 70 65 81 67 83 / 30 10 10 10 -
HONDO MUNI AIRPORT 76 65 81 66 84 / 20 10 10 10 -
SAN MARCOS MUNI AIRPORT 73 66 82 66 84 / 30 10 10 10 -
LA GRANGE - FAYETTE REGIONAL 74 68 81 68 82 / 40 10 10 10 10
SAN ANTONIO INTL AIRPORT 75 66 81 67 83 / 20 10 10 10 -
STINSON MUNI AIRPORT 76 66 81 67 85 / 30 10 10 10 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...00
SYNOPTIC/GRIDS...76
PUBLIC SERVICE/DATA COLLECTION...12
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
708 AM CDT SUN APR 5 2015
.AVIATION...
THE FIRST ROUND OF SHOWERS AND THUNDERSTORMS ARE NOW EXITING
NORTHEAST WITH A THIN LINE OF -RA/-DZ PASSING ACROSS THE CITY
AT THIS HOUR. THE NEXT SHORTWAVE DISTURBANCE IS TRAVELING OUT OF
THE LOWER RIO GRANDE THIS MORNING AND IS TIMED TO REACH THE REGION
EARLY THIS AFTERNOON. ANTICIPATING WIDELY SCATTERED SHOWERS (MAYBE
AN ISOLATED STORM) TO AFFECT SE TX FROM EARLY AFTERNOON THROUGH
AROUND SUNSET. RETURN FLOW WILL INCREASE MOISTURE LEVELS AND A
VICINITY WARM FRONTAL BOUNDARY SNEAKING INTO THE COASTAL BEND WILL
BOTH BE REASONS TO LOWER CEILINGS INTO MVFR. EARLY EVENING COOLING
SURFACE SHOULD MAKE FOR CONDUCIVE CONDITIONS FOR THE FURTHER LOWERING
OF OVERCAST INTO LATE EVENING/EARLY MORNING IFR. 31
&&
.PREV DISCUSSION... /ISSUED 421 AM CDT SUN APR 5 2015/
DISCUSSION...
AREAS OF RAIN WITH EMBEDDED SHOWERS AND THUNDERSTORMS ARE FOUND ACROSS
OUR NORTHERN AND WESTERN COUNTIES EARLY THIS MORNING. ANTICIPATE ACTIVITY
TO FILL IN ACROSS MUCH OF THE AREA OVER THE NEXT SEVERAL HOURS AS A
DISTURBANCE IN THE SOUTHWEST FLOW ALOFT MOVES ACROSS THE STATE. IF THE
LATEST HRRR IS CORRECT...BEST RAIN CHANCES AND HIGHEST RAINFALL AMOUNTS
WILL END UP BEING GENERALLY ALONG/NORTH OF INTERSTATE 10. RAINS WILL
COME TO AN END FROM WEST TO EAST AS THE DAY PROGRESSES...AND IT STILL
LOOKS LIKE THE FIRST COUPLE DAYS OF THE UPCOMING WEEK WILL BE WARM AND
DRY WITH FALLING PRECIPITABLE WATER VALUES. AS WE HEAD INTO THE END
OF THE WEEK AND ON INTO NEXT WEEKEND...RAIN CHANCES COME BACK INTO THE
FORECAST AS MOISTURE LEVELS INCREASE AND A FRONTAL BOUNDARY ENTERS THE
AREA. MODELS ARE SHOWING SOME DIFFERENCES IN THE TIMING AND STRENGTH
OF A STORM SYSTEM NEXT WEEKEND. WE`LL NEED TO WATCH HOW THINGS EVOLVE
AS SOME MODELS ARE POINTING TOWARD A POSSIBLE LINE OF STRONG/SEVERE
STORMS A WEEK FROM TODAY. 42
MARINE...
HIGH PRESSURE CENTERED OVER THE EASTERN UNITED STATES...IN RELATION
TO LOWER PLAINS PRESSURES...WILL MAINTAIN A PERSISTENT LIGHT TO
OCCASIONALLY MODERATE ONSHORE FLOW THROUGH THE UPCOMING WEEK. A
PASSING WEAK SHORTWAVE DISTURBANCE WILL HAVE SLIGHT CHANCES FOR A
BRIEF SHOWER OR ISOLATED THUNDERSTORM IN THROUGH THE DAY. AFTER
SEVERAL DAYS OF DRY WEATHER...RAIN AND STORM CHANCES WILL INCREASE
FROM THE APPROACH AND EVENTUAL PASSAGE OF THE NEXT UPPER TROUGH
NEXT WEEKEND INTO EARLY NEXT WEEK. 31
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 73 66 81 67 83 / 60 10 10 10 10
HOUSTON (IAH) 76 66 82 69 83 / 40 10 10 10 10
GALVESTON (GLS) 76 70 79 71 76 / 20 10 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...42
AVIATION/MARINE...31
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
700 AM CDT SUN APR 5 2015
.UPDATE...
AS NOTED IN THE AVIATION DISCUSSION BELOW...CONDITIONS CONTINUE TO
LOOK INCREASINGLY STABLE ON BOTH RADAR AND RADAR DERIVED WIND
PATTERNS. HI-RES MODEL SOLUTIONS STILL SHOW SOME LIGHT RAINS
POSSIBLE OVER CENTRAL TX AND THE COASTAL PRAIRIES...BUT UNIFORM
WINDS AND A PROBABLE CAPPING INVERSION WOULD SUGGEST JUST A FEW
SPRINKLES. A FEW THUNDERSTORMS ARE STILL ACCOUNTED FOR IN THE
AFTERNOON HOURS...AS THE ABSENCE OF A FRONT COULD ALLOW FOR ADDED
SUNSHINE AND ENHANCE AREAS OF DIFFERENTIAL HEATING.
&&
.PREV DISCUSSION... /ISSUED 647 AM CDT SUN APR 5 2015/
AVIATION...
EXPECT IFR CEILINGS ALONG WITH SOME REDUCED VISBYS ALONG THE
SAT/SSF/AUS SITES THROUGH THE MORNING HOURS. CLOUD DECKS HAVE BEEN
GOING DOWN THE PAST FEW HOURS WHILE SAT IS NOW REPORTING SOME
LIGHT RAIN/DRIZZLE. AUS SHOULD GO IFR OVER THE NEXT COUPLE OF
HOURS WHILE DRT HAS BEEN HANGING NEAR 3000FT. AM BRINGING DRT
DOWN TO MVFR BUT BY AFTERNOON THE HRRR IS SHOWING WESTERN AREAS TO
GET TO VFR. BECAUSE THE GFS/NAM HAVE BEEN WAY OVERDOING THE RAIN
THIS MORNING...FEEL THAT THE HRRR HAS A BETTER FEEL. I ALSO BRING
SAT/SSF INTO VFR BY LATE IN THE DAY AS BATCH OF MOISTURE AND LIFT
MOVE NE OF THE AREA. LOOKS LIKE ALL SITES WILL RETURN TO MVFR BY
MONDAY MORNING AS THE LOW LEVEL JET STRENGTHENS. HAVE REMOVED MOST
OF THE MENTION OF PRECIP FOR TODAY AS THE RAIN HAS NOT
MATERIALIZED.
PREV DISCUSSION... /ISSUED 349 AM CDT SUN APR 5 2015/
SHORT TERM (TODAY THROUGH MONDAY)...
WEAK FRONTAL INVERSION IS MOSTLY WASHED AWAY...LEAVING A REDUCED
POTENTIAL FOR OVERRUNNING RAIN AND THUNDERSTORMS. A FEW NEW
CLUSTERS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TO REDEVELOP
OVER AREAS ALONG AND EAST OF I-35 THROUGH THIS MORNING...BUT MOST
OF THE RAINS ARE LIGHT SPRINKLES OF A TRACE TO A FEW HUNDREDTHS OF
AN INCH. PLAN VIEW PLOTS OF THE VAD WINDS SHOW THE WINDS ABOVE THE
BOUNDARY LAYER ARE TURNING S TO SW OVER THE WEST AND CENTRAL
TX...SO THE LAYER OF CLOUDINESS SHOULD BEGIN TO BREAK UP LATER
TODAY WITH TEMPERATURES REBOUNDING BACK TO NORMALS.
OVER W TX...SPC HAS INDICATED A MARGINAL RISK OF SEVERE WEATHER
TRIGGERED OFF HIGHER TERRAIN AND A DRY-LINE. A FEW STORMS COULD
MOVE INTO VAL VERDE COUNTY...BUT SHOULD WEAKEN WHEN MOVING INTO AN
INCREASINGLY CAPPED ENVIRONMENT. WARMER TEMPERATURES TODAY INTO
MONDAY COULD FURTHER INCREASE DRY-LINE ACTIVITY OVER W TX LATE
MONDAY AS THE WIND FLOW IN THE MID LEVELS REMAINS MOSTLY ZONAL AND
LOW LEVEL MOISTURE DEEPENS OVER THE SOUTHERN EDWARDS PLATEAU.
LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...
ALOFT A LOW AMPLITUDE RIDGE MAINTAINS A ZONAL AND SLIGHTLY SWLY
FLOW ALOFT...WHICH IS TYPICALLY A BREEZY AND STABLE PATTERN FOR
THIS AREA. HOWEVER...MODEL CONSENSUS POPULATION OF POPS SUGGESTS A
GOOD POTENTIAL FOR WESTERLY SHORTWAVE ACTIVITY TO MOVE INTO THIS
STABLE PATTERN FOR DAILY ROUNDS OF DRY-LINE ACTIVITY OVER MAINLY
WESTERN AREAS WEDNESDAY...AND A NEWD EJECTION OF AN UPPER LOW
PASSING TO THE NW HELPING TO DRIVE THE SHORTWAVE EAST INTO CENTRAL
TX THURSDAY INTO FRIDAY. THE CURRENT BELIEF IS THAT THIS PATTERN
IS A BIT BULLISH...AND A SLIGHT LEAN TO THE DRIER ECMWF AND
CANADIAN MODELS IS FAVORED OVER A MUCH STORMIER GFS. IF THE DRIER
SOLUTIONS WIN OUT...MUCH OF THE AREA COULD CONTINUE TO DRY OUT AND
LEAD TO A WARMING TREND IN EXTENDED PERIOD TEMPERATURE FORECASTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 74 66 82 66 84 / 30 10 10 10 -
AUSTIN BERGSTROM INTL AIRPORT 74 66 80 66 83 / 30 10 10 10 -
NEW BRAUNFELS MUNI AIRPORT 76 66 83 66 84 / 30 10 10 10 -
BURNET MUNI AIRPORT 72 64 81 65 83 / 20 10 10 10 -
DEL RIO INTL AIRPORT 77 65 87 68 87 / 20 20 10 20 10
GEORGETOWN MUNI AIRPORT 72 65 81 67 83 / 30 10 10 10 -
HONDO MUNI AIRPORT 77 65 81 66 84 / 20 10 10 10 -
SAN MARCOS MUNI AIRPORT 75 66 82 66 84 / 30 10 10 10 -
LA GRANGE - FAYETTE REGIONAL 76 68 81 68 82 / 40 10 10 10 10
SAN ANTONIO INTL AIRPORT 76 66 81 67 83 / 20 10 10 10 -
STINSON MUNI AIRPORT 77 66 81 67 85 / 30 10 10 10 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...09
SYNOPTIC/GRIDS...18
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
647 AM CDT SUN APR 5 2015
.AVIATION...
EXPECT IFR CEILINGS ALONG WITH SOME REDUCED VISBYS ALONG THE
SAT/SSF/AUS SITES THROUGH THE MORNING HOURS. CLOUD DECKS HAVE BEEN
GOING DOWN THE PAST FEW HOURS WHILE SAT IS NOW REPORTING SOME
LIGHT RAIN/DRIZZLE. AUS SHOULD GO IFR OVER THE NEXT COUPLE OF
HOURS WHILE DRT HAS BEEN HANGING NEAR 3000FT. AM BRINGING DRT
DOWN TO MVFR BUT BY AFTERNOON THE HRRR IS SHOWING WESTERN AREAS TO
GET TO VFR. BECAUSE THE GFS/NAM HAVE BEEN WAY OVERDOING THE RAIN
THIS MORNING...FEEL THAT THE HRRR HAS A BETTER FEEL. I ALSO BRING
SAT/SSF INTO VFR BY LATE IN THE DAY AS BATCH OF MOISTURE AND LIFT
MOVE NE OF THE AREA. LOOKS LIKE ALL SITES WILL RETURN TO MVFR BY
MONDAY MORNING AS THE LOW LEVEL JET STRENGTHENS. HAVE REMOVED MOST
OF THE MENTION OF PRECIP FOR TODAY AS THE RAIN HAS NOT
MATERIALIZED.
&&
.PREV DISCUSSION... /ISSUED 349 AM CDT SUN APR 5 2015/
SHORT TERM (TODAY THROUGH MONDAY)...
WEAK FRONTAL INVERSION IS MOSTLY WASHED AWAY...LEAVING A REDUCED
POTENTIAL FOR OVERRUNNING RAIN AND THUNDERSTORMS. A FEW NEW
CLUSTERS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TO REDEVELOP
OVER AREAS ALONG AND EAST OF I-35 THROUGH THIS MORNING...BUT MOST
OF THE RAINS ARE LIGHT SPRINKLES OF A TRACE TO A FEW HUNDREDTHS OF
AN INCH. PLAN VIEW PLOTS OF THE VAD WINDS SHOW THE WINDS ABOVE THE
BOUNDARY LAYER ARE TURNING S TO SW OVER THE WEST AND CENTRAL
TX...SO THE LAYER OF CLOUDINESS SHOULD BEGIN TO BREAK UP LATER
TODAY WITH TEMPERATURES REBOUNDING BACK TO NORMALS.
OVER W TX...SPC HAS INDICATED A MARGINAL RISK OF SEVERE WEATHER
TRIGGERED OFF HIGHER TERRAIN AND A DRY-LINE. A FEW STORMS COULD
MOVE INTO VAL VERDE COUNTY...BUT SHOULD WEAKEN WHEN MOVING INTO AN
INCREASINGLY CAPPED ENVIRONMENT. WARMER TEMPERATURES TODAY INTO
MONDAY COULD FURTHER INCREASE DRY-LINE ACTIVITY OVER W TX LATE
MONDAY AS THE WIND FLOW IN THE MID LEVELS REMAINS MOSTLY ZONAL AND
LOW LEVEL MOISTURE DEEPENS OVER THE SOUTHERN EDWARDS PLATEAU.
LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...
ALOFT A LOW AMPLITUDE RIDGE MAINTAINS A ZONAL AND SLIGHTLY SWLY
FLOW ALOFT...WHICH IS TYPICALLY A BREEZY AND STABLE PATTERN FOR
THIS AREA. HOWEVER...MODEL CONSENSUS POPULATION OF POPS SUGGESTS A
GOOD POTENTIAL FOR WESTERLY SHORTWAVE ACTIVITY TO MOVE INTO THIS
STABLE PATTERN FOR DAILY ROUNDS OF DRY-LINE ACTIVITY OVER MAINLY
WESTERN AREAS WEDNESDAY...AND A NEWD EJECTION OF AN UPPER LOW
PASSING TO THE NW HELPING TO DRIVE THE SHORTWAVE EAST INTO CENTRAL
TX THURSDAY INTO FRIDAY. THE CURRENT BELIEF IS THAT THIS PATTERN
IS A BIT BULLISH...AND A SLIGHT LEAN TO THE DRIER ECMWF AND
CANADIAN MODELS IS FAVORED OVER A MUCH STORMIER GFS. IF THE DRIER
SOLUTIONS WIN OUT...MUCH OF THE AREA COULD CONTINUE TO DRY OUT AND
LEAD TO A WARMING TREND IN EXTENDED PERIOD TEMPERATURE FORECASTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 74 66 82 66 84 / 50 10 10 10 -
AUSTIN BERGSTROM INTL AIRPORT 74 66 80 66 83 / 60 10 10 10 -
NEW BRAUNFELS MUNI AIRPORT 76 66 83 66 84 / 50 10 10 10 -
BURNET MUNI AIRPORT 72 64 81 65 83 / 40 10 10 10 -
DEL RIO INTL AIRPORT 77 65 87 68 87 / 20 20 10 20 10
GEORGETOWN MUNI AIRPORT 72 65 81 67 83 / 50 10 10 10 -
HONDO MUNI AIRPORT 77 65 81 66 84 / 30 10 10 10 -
SAN MARCOS MUNI AIRPORT 75 66 82 66 84 / 60 10 10 10 -
LA GRANGE - FAYETTE REGIONAL 76 68 81 68 82 / 60 10 10 10 10
SAN ANTONIO INTL AIRPORT 76 66 81 67 83 / 30 10 10 10 -
STINSON MUNI AIRPORT 77 66 81 67 85 / 30 10 10 10 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...09
SYNOPTIC/GRIDS...18
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
421 AM CDT SUN APR 5 2015
.DISCUSSION...
AREAS OF RAIN WITH EMBEDDED SHOWERS AND THUNDERSTORMS ARE FOUND ACROSS
OUR NORTHERN AND WESTERN COUNTIES EARLY THIS MORNING. ANTICIPATE ACTIVITY
TO FILL IN ACROSS MUCH OF THE AREA OVER THE NEXT SEVERAL HOURS AS A
DISTURBANCE IN THE SOUTHWEST FLOW ALOFT MOVES ACROSS THE STATE. IF THE
LATEST HRRR IS CORRECT...BEST RAIN CHANCES AND HIGHEST RAINFALL AMOUNTS
WILL END UP BEING GENERALLY ALONG/NORTH OF INTERSTATE 10. RAINS WILL
COME TO AN END FROM WEST TO EAST AS THE DAY PROGRESSES...AND IT STILL
LOOKS LIKE THE FIRST COUPLE DAYS OF THE UPCOMING WEEK WILL BE WARM AND
DRY WITH FALLING PRECIPITABLE WATER VALUES. AS WE HEAD INTO THE END
OF THE WEEK AND ON INTO NEXT WEEKEND...RAIN CHANCES COME BACK INTO THE
FORECAST AS MOISTURE LEVELS INCREASE AND A FRONTAL BOUNDARY ENTERS THE
AREA. MODELS ARE SHOWING SOME DIFFERENCES IN THE TIMING AND STRENGTH
OF A STORM SYSTEM NEXT WEEKEND. WE`LL NEED TO WATCH HOW THINGS EVOLVE
AS SOME MODELS ARE POINTING TOWARD A POSSIBLE LINE OF STRONG/SEVERE
STORMS A WEEK FROM TODAY. 42
&&
.MARINE...
HIGH PRESSURE CENTERED OVER THE EASTERN UNITED STATES...IN RELATION
TO LOWER PLAINS PRESSURES...WILL MAINTAIN A PERSISTENT LIGHT TO
OCCASIONALLY MODERATE ONSHORE FLOW THROUGH THE UPCOMING WEEK. A
PASSING WEAK SHORTWAVE DISTURBANCE WILL HAVE SLIGHT CHANCES FOR A
BRIEF SHOWER OR ISOLATED THUNDERSTORM IN THROUGH THE DAY. AFTER
SEVERAL DAYS OF DRY WEATHER...RAIN AND STORM CHANCES WILL INCREASE
FROM THE APPROACH AND EVENTUAL PASSAGE OF THE NEXT UPPER TROUGH
NEXT WEEKEND INTO EARLY NEXT WEEK. 31
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 73 66 81 67 83 / 60 10 10 10 10
HOUSTON (IAH) 76 66 82 69 83 / 40 10 10 10 10
GALVESTON (GLS) 76 70 79 71 76 / 20 10 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...42
AVIATION/MARINE...31
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
926 PM CDT MON APR 6 2015
.UPDATE...
ADJUSTING POPS AND LOWERING CHANCES FOR THUNDER THIS EVENING.
POCKET OF HIGHER REFLECTIVITY MOVING ALONG AND NORTH OF A LONE
ROCK...MADISON TO WATERTOWN LINE LIKELY DUE TO MELTING...AS THE
UNIFORM RELATIVELY NARROW BAND OF HIGHER REFLECTIVITIES ON CROSS
SECTIONS COINCIDE WELL WITH THE DRY...WARM/ABOVE 0C/ LAYER BETWEEN
5300 FT AND 10 K FT ON AREA RAP SOUNDINGS. RAINFALL AMOUNTS AND
VSBYS BELOW THIS POCKET MORE IN LINE WITH LIGHT RAIN VERSUS
MODERATE.
LATEST NAM IN LINE WITH HI-RES/RAPID UPDATE MODELS AND SUPPORT
CHANCE POPS ONCE THIS INITIAL BAND MOVES THROUGH.
&&
.AVIATION/06Z TAFS/...
HAD LOWERED CIGS AT KMKE EARLIER AND LOOKS LIKE THEY WILL STAY
AROUND 500 FT UNTIL BETWEEN 05Z AND 07Z ON MOST RECENT RAP
FORECAST SOUNDINGS. WHILE LATEST HI-RES/RAPID UPDATE MODELS
SUPPORT THE REDUCED CHANCES FOR PRECIP SHOWN ON THE LATEST
NAM...CLOUD TRENDS ON SATELLITE IMAGERY SHOW WIDESPREAD MVFR CIGS
STILL ON TRACK TO OVERSPREAD AREA AFTER 06Z. WILL MONITOR TRENDS
AT KMKE AND INLAND AND AWAIT A LOOK AT COMPLETE 07/00Z DATA FOR
POTENTIAL IFR CIGS TO CONTINUE RIGHT THROUGH TUESDAY AS INDICATED
BY SOME OF THE EARLIER GUIDANCE.
&&
.MARINE...
STARTED SMALL CRAFT ADVISORY FOR SOUTHERN ZONES AT 02Z WITH
NORTHERN ZONES. NORTHEAST WINDS HAVE RISEN TO 10 TO 20 KNOTS WITH
GUSTS TO 22 TO 25 KNOTS AS FAR SOUTH AS WAUKEGAN. THERE MAY BE A
BRIEF LULL TO THESE WINDS FOR A COUPLE OF HOURS...THEN THEY PICK
BACK UP AGAIN RIGHT AFTER MIDNIGHT. HOWEVER...THE FETCH IS
FAVORABLE FOR THE LARGER WAVES AND EVEN THE BRIEF LULL IN WIND
SPEEDS MAY ARE NOT EXPECTED TO BE ENOUGH TO OFFSET THE FAVORABLE
DIRECTION.
&&
.PREV DISCUSSION... /ISSUED 646 PM CDT MON APR 6 2015/
TONIGHT AND TUESDAY...FORECAST CONFIDENCE...HIGH
A SHOT OF WARM ADVECTION ALOFT WILL LIKELY KICK OFF SOME SHOWERS
ACROSS SOUTHERN WISCONSIN THIS EVENING AND OVERNIGHT. A BIT
CONCERNED WITH SOME MID LEVEL DRY AIR...BUT SEEMED LIKE ENOUGH
OVERALL MOISTURE AND LIFT TO KEEP AT LEAST CHANCE POPS. IT WILL TURN
OVERCAST THIS EVENING AND WINDS WILL STAY UP OVERNIGHT...ALLOWING
TEMPERATURES TO STAY SEVERAL DEGREES MILDER THAN LAST NIGHT.
IT LOOKS DRY FOR MUCH OF THE MORNING AND AFTERNOON ON
TUESDAY...THOUGH THERE COULD BE A FEW STRAY SHOWERS. CHANCES WILL BE
INCREASING BY LATE AFTERNOON IN THE SOUTHWEST AS BETTER FORCING AND
MOISTURE ARRIVE. LOOKS LIKE ENOUGH ELEVATED INSTABILITY TO KEEP
THUNDER MENTION GOING IN THE SOUTHWEST LATE AFTERNOON. CLOUDY SKIES
AND EAST WINDS WILL RESULT IN BELOW NORMAL TEMPS TUESDAY...THE
COOLEST TEMPS NEAR LAKE MICHIGAN.
TUESDAY NIGHT...FORECAST CONFIDENCE IS HIGH.
THIS SHOULD BE OUR FIRST DECENT SHOT AT SOME MEANINGFUL RAINFALL.
WE GET A NICE SURGE OF WARM AIR ADVECTION AND ISENTROPIC
LIFT...THAT HAS SOME MOISTURE WITH IT. THE MODELS DEPICT...IN
VARYING FASHION...A SHORT WAVE ROLLING THROUGH DURING THE EVENING.
ADDITIONALLY...THERE IS SOME ELEVATED INSTABILITY...SO WE COULD
HEAR SOME THUNDER. THE RAIN WILL MOVE IN QUICKLY DURING THE
EVENING...THEN DIMINISH FROM SOUTHWEST TO NORTHEAST AFTER MIDNIGHT
AS THE WAVE MOVES OFF.
WEDNESDAY...FORECAST CONFIDENCE IS MEDIUM.
WE COULD HAVE SOME LINGERING RAIN ACROSS THE EAST IN THE
MORNING...THEN THINGS DRY OUT FOR THE LATE MORNING THROUGH MID
AFTERNOON. THE NEXT SURGE OF MOISTURE/ISENTROPIC LIFT/WARM
ADVECTION OUT AHEAD OF THE NEXT APPROACHING LOW COULD BRING SOME
RAIN INTO THE AREA TOWARD EVENING.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...FORECAST CONFIDENCE IS
MEDIUM.
WE ENTER A MUCH MORE AMPLIFIED PATTERN DURING THIS PERIOD WITH THE
MARQUEE FEATURE BEING AND ESPECIALLY VIGOROUS SHORT WAVE THAT
TILTS NEGATIVELY AND LIFTS ACROSS WISCONSIN THURSDAY AFTERNOON
AND EVENING. AHEAD OF THE LOW WEDNESDAY NIGHT...THE LOW LEVEL JET
INCREASES...PROVIDING A GOOD SURGE OF MOIST...WARM AIR ADVECTION.
AGAIN...THERE IS ELEVATED CAPE AVAILABLE...SO POPS HAVE
INCREASED. THIS WOULD BE OUR SECOND ROUND OF MEANINGFUL PRECIP
FOR THE WEEK AHEAD.
ON THURSDAY...RAPID SURFACE CYCLOGENESIS WILL RESULT IN A DEEPENING
SURFACE LOW THAT SHOULD ROUGHLY TRACK FROM THE IA/MO BORDER
NORTHEAST ACROSS SOUTHERN WISCONSIN ON THURSDAY. THE BIG QUESTION
IS HOW FAR NORTH THE WARM FRONT WILL MAKE IT INTO WISCONSIN AND
HOW MUCH IF ANY CLEARING WE/LL SEE. TEMPS MAY SNEAK INTO THE MID
AND UPPER 60S ALONG THE STATE LINE...WHILE STAYING IN THE 40S
ACROSS THE NORTHEAST FORECAST AREA DUE TO THE PERSISTENT EASTERLY
FLOW OFF THE LAKE NORTH OF THE WARM FRONT. TEMPS WILL BE VERY
TRICKY GIVEN THE UNCERTAINTY OF THE FRONTAL LOCATION ON THURSDAY.
THE COUPLING OF THAT INTENSE...NEGATIVE TILT SHORT WAVE WITH THE
POTENTIAL OF A WARM...MOIST SECTOR AHEAD OF THE LOW GETTING INTO
SOUTHERN WISCONSIN COULD RESULT IN SOME STRONG THUNDERSTORMS
THURSDAY AFTERNOON. THIS WOULD BE OUR THIRD ROUND OF MEANINGFUL
RAINFALL. SPC DOES PUSH A MARGINAL RISK OF SEVERE STORMS INTO OUR
FAR SOUTHWEST...BUT THE SEVERE POTENTIAL WILL BE SOMEWHAT FLUID
OVER THE NEXT FEW DAYS. THE GFS/NAM BOTH SUGGEST WE COULD SEE
1500J/KG OF CAPE AVAILABLE DURING THE AFTERNOON. DEEP LAYER SHEAR
IS PUSHING 40-50KTS. BUT...AS ALWAYS...IT DEPENDS ON CLOUD
COVER...FRONTAL POSITION AND HOW MUCH HEATING WE CAN GET.
THE LOW WILL LIFT OUT OF THE AREA THURSDAY NIGHT...SO LOOK FOR THE
RAIN TO DIMINISH IN INTENSITY FROM SOUTH TO NORTH OVERNIGHT.
FRIDAY THROUGH SUNDAY...FORECAST CONFIDENCE IS MEDIUM.
WE COULD SEE SOME LINGERING SHOWERS ON FRIDAY...HOPEFULLY JUST IN
THE MORNING WITH CLEARING IN THE AFTERNOON. BUT...DON/T WANT TO
TRY AND GET CUTE ON DETAILS THIS FAR OUT. THEN HIGH PRESSURE TAKES
OVER THROUGH SATURDAY NIGHT WITH DRY CONDITIONS EXPECTED.
ANOTHER APPROACHING LOW PRESSURE SYSTEM SHOULD BRING OUR NEXT
CHANCE FOR RAIN LATER SUNDAY INTO MONDAY.
AVIATION/00Z TAFS/...UPDATED
LOW STRATUS MOVING DOWN THE WESTERN SHORE OF LAKE MICHIGAN IS MOVING
INLAND TOWARD KMKE BASED ON WEB CAMS...WITH PERIODIC BROKEN CIGS AS
FAR INLAND AS KSBM. HAVE LOWERED KMKE TO 1K FT WITH A POTENTIAL FOR
AS LOW AS 600 FT. WILL WATCH TRENDS CAREFULLY FOR KENW.
OTHERWISE VFR CONDITIONS WILL CONTINUE AT REST OF TAF SITES INTO
EARLY EVENING. WILL SEE CLOUDS SLOWLY LOWER...WITH WIDESPREAD MVFR
CIGS LIKELY ARRIVING BY MID/LATE EVENING. LOWER CLOUDS WILL STICK
AROUND THROUGH TUESDAY...POSSIBLY BECOMING IFR LATER TONIGHT INTO
TUESDAY.
A SHOT OF WARM ADVECTION ALOFT WILL LIKELY KICK OFF SOME SHOWERS
ACROSS SOUTHERN WISCONSIN THIS EVENING AND OVERNIGHT. A BIT
CONCERNED WITH SOME MID LEVEL DRY AIR...BUT SEEMED LIKE ENOUGH
OVERALL MOISTURE AND LIFT TO KEEP AT LEAST A CHANCE GOING. BETTER
CHANCE FOR WIDESPREAD SHOWERS AND A FEW STORMS WILL ARRIVE LATE
TUESDAY AFTERNOON AND INTO THE EVENING.
MARINE...
WILL BE ISSUING A SMALL CRAFT ADVISORY FOR TONIGHT INTO
TUESDAY...MAYBE EVEN THROUGH WEDNESDAY...AS PERSISTENT EAST TO
NORTHEAST WINDS BUILD HIGH WAVES. MAY SEE GUSTS TO 25 KNOTS AT
TIMES TUESDAY.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 AM CDT WEDNESDAY FOR LMZ643>646.
&&
$$
UPDATE...REM
TONIGHT/TUESDAY AND AVIATION/MARINE...DDV
TUESDAY NIGHT THROUGH MONDAY...DAVIS
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
333 AM CDT TUE APR 7 2015
.SHORT TERM...TODAY THROUGH FRIDAY
SHOWERS AND A FEW THUNDERSTORMS DEVELOPED ACROSS THE STATE DURING
THE OVERNIGHT HOURS WITH SOME PATCHY FOG DEVELOPING. HRRR SUGGESTS
THESE SHOWERS WILL INCREASE IN COVERAGE THROUGH THE EARLY MORNING
HOURS AND KEEP RAIN CHANCES IN THE FORECAST THROUGH THE LATE
MORNING...GENERALLY ACROSS THE EASTERN HALF OF THE STATE.
OTHERWISE...PRECIPITATION WILL BE LIMITED ON TUESDAY WITH A STRONGLY
CAPPED ATMOSPHERE IN PLACE. THE BEST CHANCES FOR
PRECIPITATION...RELATIVELY SPEAKING...WILL BE ACROSS NORTHERN
ARKANSAS...BUT EVEN STILL NOT CONFIDENT ENOUGH TO GO ABOVE SLIGHT
CHANCES. WINDS WILL BE A BIT ON THE STRONG SIDE TODAY...BUT NOT
STRONG ENOUGH TO WARRANT A LAKE WIND ADVISORY.
WEDNESDAY...PRECIPITATION CHANCES WILL SOMEWHAT INCREASE...MAINLY
ACROSS WESTERN ARKANSAS AS A COLD FRONT SLOWLY MARCHES TOWARD THE
STATE. ATMOSPHERE STILL LOOKS TO BE FAIRLY CAPPED ON
WEDNESDAY...HOWEVER UPPER LEVEL RIDGE WILL BEGIN TO PUSH TO THE EAST
ALLOWING TEMPERATURES ALOFT TO SOMEWHAT COOL AND SOMEWHAT WEAKENING
THE CAP.
THURSDAY CONTINUES TO LOOK LIKE THE BEST CHANCE FOR SEVERE WEATHER
ACROSS THE CWA. SURFACE LOW PRESSURE WILL TRACK FROM COLORADO
THROUGH IOWA...DRAGGING ITS ASSOCIATED COLD FRONT THROUGH THE STATE.
MODEL SOUNDINGS TO CONTINUE TO SHOW THE POTENTIAL FOR SEVERE WEATHER
IN THE STATE WILL ALL MODES POSSIBLE. THE COLD FRONT ITSELF WILL NOT
ENTER THE STATE UNTIL 00Z...AND PUSH THROUGH THE STATE BY 12Z
FRIDAY. WITH AMPLE MOISTURE IN PLACE AFTER QUITE A FEW DAYS OF
STRONG SOUTHERLY FLOW...HEAVY RAIN CONTINUES TO BE A CONCERN WITH
THIS SYSTEM.
HIGH PRESSURE AND DRY WEATHER WILL MOVE INTO THE STATE FOR
FRIDAY...WITH THE FRONT STALLING JUST TO THE SOUTH OF THE STATE.
TEMPERATURES WILL RETURN TO NEAR NORMAL LEVELS.
&&
.LONG TERM...FRIDAY NIGHT THROUGH MONDAY
HIGH PRESSURE WILL BE MOVING THROUGH THE AREA ON FRIDAY NIGHT...WITH
THE FRONT STALLED OUT JUST TO THE SOUTH OF THE REGION. THE HIGH WILL
MOVE EASTWARD ON SATURDAY...WITH RETURN FLOW SETTING UP AS THE FRONT
BEGINS TO BACK NORTHWARD. SHOWERS AND THUNDERSTORMS WILL RETURN TO
THE FORECAST...WITH THE HIGHEST CHANCES ON SUNDAY AND SUNDAY NIGHT...
AS THE WARM FRONT MOVES THROUGH...ALONG WITH AN UPPER TROUGH WITH A
BIT OF A NEGATIVE TILT. EXTENDED RANGE MODELS ARE SHOWING A SURFACE
LOW DEVELOPING SUNDAY NIGHT INTO MONDAY...DRAGGING A COLD FRONT INTO
THE REGION DURING THE DAY.
IF THE AFOREMENTIONED SCENARIO PANS OUT...SEVERE THUNDERSTORMS MAY
BE POSSIBLE. ALSO...WITH GULF AND PACIFIC MOISTURE LINING UP...
PRECIPITABLE WATER VALUES WILL BE APPROACHING TWO INCHES. THUS...
HEAVY RAINFALL WOULD BE A POSSIBILITY AS WELL. WILL CONTINUE TO
MONITOR THIS POTENTIAL HAZARDOUS WEATHER SETUP...AND ADJUST
SUCCESSIVE FORECASTS ACCORDINGLY. ONE THING THAT IS CONCERNING IS
THAT...THOUGH THE SMALL DETAILS DIFFER TO VARYING DEGREES...THE
MODELS ARE IN REMARKABLY GOOD AGREEMENT FOR SIX DAYS OUT. STAY
TUNED.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 80 65 82 65 / 20 10 20 30
CAMDEN AR 83 65 84 66 / 20 10 10 20
HARRISON AR 80 63 82 63 / 20 20 30 40
HOT SPRINGS AR 81 67 82 66 / 20 10 10 20
LITTLE ROCK AR 82 66 83 65 / 20 10 10 20
MONTICELLO AR 82 65 84 67 / 20 10 10 10
MOUNT IDA AR 80 66 79 67 / 20 10 10 30
MOUNTAIN HOME AR 79 63 83 63 / 20 20 30 40
NEWPORT AR 80 65 82 66 / 20 20 20 20
PINE BLUFF AR 82 65 83 65 / 20 10 10 20
RUSSELLVILLE AR 81 63 83 64 / 20 10 20 30
SEARCY AR 80 63 82 64 / 20 10 20 20
STUTTGART AR 81 66 82 66 / 20 10 10 20
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...65 / LONG TERM...57
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
302 AM PDT TUE APR 7 2015
...LATE SEASON STORM TO IMPACT THE REGION THROUGH TONIGHT...
.SYNOPSIS...RAIN WILL GO THROUGH OUR AREA THIS MORNING. ALONG
WITH LOCALLY HEAVY RAINFALL...THUNDERSTORMS WITH SMALL HAIL AND
GUSTY WINDS WILL BE POSSIBLE AS THE SYSTEM MOVES INLAND. IN
ADDITION...SNOW ACCUMULATIONS WILL BE POSSIBLE OVER THE SANTA
LUCIA RANGE ABOVE 4000 FEET. DRY WEATHER CONDITIONS RETURN BY
MIDWEEK AS THE SYSTEM EXITS THE REGION.
&&
.DISCUSSION...AS OF 3:00 AM PDT TUESDAY...AS EXPECTED RADAR
RETURNS HAVE INCREASED THROUGH THE OVERNIGHT HOURS AS A STRONG
FRONT MOVES ACROSS OUR AREA. LATEST LOOK AT KMUX SHOWS A BAND OF
MODERATE RAIN ENTERING THE SF BAY REGION ASSOCIATED WITH THE
HEAVILY ADVERTISED COLD FRONT. SO FAR RAINFALL RETURNS HAVE BEEN
DECENT WITH PARTS OF SONOMA COUNTY OVER THREE QUARTERS OF AN
INCH. LATEST RUN OF THE HRRR SHOWS THE BEST POTENTIAL FOR MODERATE
TO POSSIBLY HEAVY RAINFALL THROUGH THE MORNING HOURS IN A REGION
FROM THE SOUTH BAY OVER TO THE FAR EAST BAY VALLEYS AND THEN SOUTH
INTO SANTA CRUZ COUNTY. THOSE SPOTS COULD EASILY SEE HALF AN INCH
BY MID-MORNING.
WINDS PICKED UP THROUGH THE EVENING HOURS ALTHOUGH STRONG GUSTS
GENERALLY HAVE BEEN CONFINED TO HIGHER ELEVATION SPOTS. A FEW
URBAN AREAS ARE SEEING GUSTS OVER 25 MPH INCLUDING BOTH THE SFO
AND OAKLAND AIRPORTS. FOR SPOTS OVER 1000 FEET GUSTS OVER 35 MPH
ARE FAIRLY COMMON ESPECIALLY FOR OUR TYPICAL WINDY SPOTS.
BEHIND THE COLD FRONT THE ATMOSPHERE WILL DESTABILIZE WITH LIFTED
VALUES EXPECTED TO DROP AS LOW AS MINUS 3 WHILE CAPE VALUES COULD
EXCEED 200 J/KG. WOULD EXPECT AT LEAST A FEW THUNDERSTORMS ACROSS
OUR AREA ALONG WITH REPORTS OF SMALL HAIL. WORTH NOTING THAT VERY
LITTLE DIRECTIONAL SHEER IS FORECAST FOR OUR AREA WITH ONLY
LIMITED SPEED SHEER WHICH WILL HELP TO LIMIT THE THREAT OF SEVERE
WEATHER. THE COOLER AIR WILL LEAD TO LOWER SNOW LEVELS WITH
ACCUMULATIONS EXPECTED OVER 4000 FEET. STILL LOOKS LIKE THE SANTA
LUCIA RANGE COULD PICK UP 3 TO 6 INCHES OF SNOW.
ALL TOO FAMILIAR RIDGE OF HIGH PRESSURE WILL BUILD BACK TO OUR AREA
STARTING ON WEDNESDAY AS THE SYSTEM DEPARTS TO THE EAST. THIS
WILL LEAD TO THE STORM TRACK HEADING BACK WELL TO THE NORTH ALONG
WITH WARMER TEMPERATURES. LONGER RANGE OUTLOOKS DO NOT INDICATE
ANY ADDITIONAL SUBSTANTIAL STORMS PAST TODAY GOING ALL OF THE WAY
TO APRIL 20TH.
&&
.AVIATION...AS OF 10:52 PM PDT MONDAY...GUSTY S-SE PRE-FRONTAL
WIND PATTERN IS EXPECTED OVER THE FORECAST AREA TONIGHT. THE COLD
FRONT WILL SWEEP QUICKLY E-SE ACROSS THE AREA AFTER MIDNIGHT FOLLOWED
BY MUCH COLDER AIR ALOFT AND INSTABILITY SHOWERS BEGINNING EARLY
TUE. ISOLATED T-STORM(S) ALSO POSSIBLE BEGINNING TUE MORNING BUT
MUCH TOO LOW CONFIDENCE TO ATTEMPT TO TIME ONE OR MORE IN THE 00Z
TAFS. A FEW LINGERING SHOWERS ARE POSSIBLE TUE AFTERNOON AND EVENING
OTHERWISE DRIER WEATHER RETURNS TUESDAY NIGHT.
VICINITY OF KSFO...S-SE WINDS EXPECTED TO TREND HIGHER NEAREST THE
COLD FRONTAL PASSAGE VERY LATE TONIGHT/EARLY TUE MORNING. SE GUSTS
UP TO 35 KNOTS LIKELY 06Z-10Z TIME-FRAME. HEAVY SHOWERS TONIGHT/EARLY
TUE MORNING. POST FRONTAL WINDS TUESDAY NOT QUITE AS GUSTY
AS PRE-FRONTAL WINDS.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...DETERIORATING WEATHER CONDITIONS ARE
EXPECTED VERY LATE AT NIGHT. MOD-HEAVY DOWNPOURS EXPECTED WITH
THE COLD FRONTAL PASSAGE EARLY TUE MORNING AS THE FRONT CONTINUES
TO MOVE SE OVER THE CENTRAL COAST. ADDITIONAL PASSING SHOWERS
LIKELY THROUGH THE REMAINDER OF TUESDAY AS THE AIR MASS ALOFT
COOLS OFF APPRECIABLY.
&&
.MARINE...AS OF 3:00 AM PDT TUESDAY...A COLD FRONT WILL MOVE THROUGH
THE COASTAL WATERS EARLY TODAY PRODUCING GUSTY WINDS...RAIN AND
THUNDERSTORMS. THE GUSTY WINDS WILL PRODUCE LOCALLY HAZARDOUS
CONDITIONS. WINDS WILL DECREASE FROM NORTH TO SOUTH THROUGH THE
DAY AS THE FRONT EXITS THE REGION WITH AN IMPROVING SEA STATE.
NORTHWEST SWELL THROUGH THE PERIOD.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...WINTER WEATHER ADVISORY...SANTA LUCIA RANGE THROUGH
TONIGHT.
SCA...SF BAY NORTH OF THE BAY BRIDGE UNTIL 8 AM
SCA...SF BAY SOUTH OF THE BAY BRIDGE UNTIL 8 AM
SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 8 AM
SCA...PIGEON PT TO PT PINOS 0-10 NM UNTIL 8 AM
SCA...PT REYES TO PIGEON PT 10-60 NM UNTIL 8 AM
SCA...PIGEON PT TO PT PINOS 10-60 NM UNTIL 8 AM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM UNTIL 11 AM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM UNTIL 11 AM
&&
$$
PUBLIC FORECAST: BELL
AVIATION: CANEPA
MARINE: MM
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AREA FORECAST DISCUSSION
NWS PUEBLO CO
1112 PM MDT MON APR 6 2015
.UPDATE...
ISSUED AT 903 PM MDT MON APR 6 2015
UPDATED FOR EXPIRATION OF RED FLAG WARNING. RH STILL VERY LOW MOST
LOCATIONS...BUT WINDS HAVE DIMINISHED ENOUGH TO LET WARNING EXPIRE
ON SCHEDULE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 245 PM MDT MON APR 6 2015
...SHORT TERM CONCERN REMAINS CRITICAL FIRE WEATHER CONDITIONS...
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS INDICATING A DEEP
SOUTHWESTERLY FLOW PATTERN ACROSS THE REGION WITH AN UPPER LOW AND
BROAD TROUGH JUST OFFSHORE THE PAC NORTHWEST COAST THROUGH THE WEST
COAST AND GREAT BASIN REGION. WATER VAPOR IMAGERY ALSO INDICATING AN
EMBEDDED SHORT WAVE TRANSLATING ACROSS THE GREAT BASIN AT THIS TIME.
LATEST SFC OBSERVATIONS INDICATING A WELL MIXED ATMOSPHERE ACROSS
THE AREA WITH BREEZY TO WINDY SOUTHWEST WINDS...WARM TEMPERATURES IN
THE 70S TO LOWER 80S LOWER ELEVATIONS...50S AND 60S ACROSS THE
HIGHER TERRAIN...DEW PTS MAINLY IN THE SINGLE DIGITS ABOVE AND BELOW
ZERO...ALL LEADING TO DANGEROUS FIRE WEATHER CONDITIONS BEING
EXPERIENCED ACROSS ALL OF THE NON SNOW COVERED AREAS OF SOUTH CENTRAL
AND SOUTHEAST COLORADO.
HOWEVER...LOW LEVEL MOISTURE IS NOT TOO FAR AWAY WITH REGIONAL
RADARS INDICATING A FINE LINE FROM NEAR DIA TO BURLINGTON AND INTO
WEST CENTRAL KANSAS...WITH DEW PTS IN THE 20S...30S AND 40S NORTH
AND EAST OF THE BOUNDARY INTO NORTHEASTERN COLORADO AND NORTHWESTERN
KANSAS.
TONIGHT AND TOMORROW...MODERATE TO STRONG SW FLOW ALOFT PROGGED TO
CONTINUE ACROSS THE AREA THROUGH THE PERIOD WITH GREAT BASIN
EMBEDDED WAVE CONTINUING TO TRANSLATE NORTH AND EAST ACROSS THE
NORTHERN ROCKIES TONIGHT AND ANOTHER SHORT WAVE PROGGED TO MOVE INTO
THE GREAT BASIN REGION THROUGH THE DAY TOMORROW. FIRST WAVE LOOKS TO
HELP PUSH LOW LEVEL MOISTURE GRADIENT/FRONT SOUTH AND WEST ACROSS
PORTIONS OF THE PALMER DVD AND NORTHERN PORTIONS OF THE SE PLAINS
TONIGHT WITH THE HRRR THE MOST AGGRESSIVE PUSHING MID 40 DEW PTS AND
STRATUS WELL INTO KIOWA AND PROWERS COUNTIES OVERNIGHT...WHICH MAY
BE A TAD OVERDONE. FURTHER WEST...WILL LIKELY SEE POOR RH RECOVERY
WITH LOWS SIMILAR TO LAST NIGHTS.
THIS BOUNDARY LOOKS TO MIX OUT THROUGH THE LATE MORNING AND EARLY
AFTERNOON TOMORROW AS LEE TROUGH STRENGTHENS ACROSS THE EASTERN
PLAINS AHEAD OF THE NEXT EMBEDDED SHORT WAVE. THIS ALL POINTS TO
ANOTHER DAY OF HIGH FIRE DANGER...ESPECIALLY FOR AREAS ALONG THE I-
25 CORRIDOR AND BACK WEST ACROSS THE REST OF THE EASTERN MTS TO THE
CONTDVD. WITH THAT SAID...HAVE UPGRADED AND EXPANDED A RED FLAG
WARNING FOR TOMORROW FROM NOON TO 8 PM FOR ALL OF THE NON SNOW
COVERED MTS...THE HIGH MT VALLEY AND THROUGH THE I-25 CORRIDOR. I
DID NOT INCLUDE THE FAR SE PLAINS WITH MARGINAL WINDS...THOUGH IF
DEEP ENOUGH MIXING CAN OCCUR...COULD SEE RED FLAG CONDITIONS THERE
AS WELL.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 245 PM MDT MON APR 6 2015
...DRY AND WINDY WEATHER CONTINUES...
A SERIES OF PROGRESSIVE TROUGHS WILL IMPACT OUR AREA OVER THE NEXT
SIX TO TEN DAYS...UNFORTUNATELY NONE OF THEM LOOK VERY ORGANIZED AND
IT LOOKS LIKE THERE WILL BE MORE WIND THAN PRECIPITATION FROM THIS
PATTERN. THE ONLY OPTIMISTIC THING THAT CAN BE SAID IS THAT THE
MODELS ARE STRUGGLING WITH THE PATTERN...SO THERE IS TIME FOR IT TO
CHANGE.
WEDNESDAY STILL LOOKS LIKE A DAY OF POTENTIALLY EXTREME FIRE
WEATHER. WITH INCREASING WRLY FLOW ALOFT...WILL SEE VERY LOW RH OVER
MOST OF THE AREA...AND ANOTHER ROUND OF STRONG-GUSTY WINDS IN THE
AFTERNOON AND EARLY EVE. HAVE HOISTED A FIRE WX WATCH FOR MOST OF
THE CWA. ONLY AREAS THAT MIGHT ESCAPE ARE THE PIKES PEAK REGION AND
THE CENTRAL MTS. TEMPS ALOFT WILL BE FALLING...SO DEPENDING ON THE
SPEED OF THE COLD FRONT THE RH VALUES FOR THE NRN AND CENTRAL MTN
AREAS MAY BE HIGH ENOUGH TO PRECLUDE RED FLAG. BUT IT WILL BE
ANOTHER DAY OF HIGH FIRE DANGER FOR THE PLAINS. EXTREME NERN
CORNER...BASICALLY KIOWA COUNTY...WILL BE A BIT SLOWER TO MIX OUT
DUE TO SOME MORNING LOW CLOUDS...BUT BY MID TO LATE AFTERNOON MOST
OF THE PLAINS SHOULD BE ON THE BREEZY-WINDY SIDE.
MODELS ARE NOW ALL ON BOARD WITH A MORE NORTHERLY TRACK FOR THE LATE
WED-THU SYSTEM. AS EXPECTED...THE OUTLIER ECMWF HAS FALLEN INTO LINE
WITH THE GFS...AND THE NAM-GFS SOLUTION HAS COME TOGETHER WITH A LOW
THAT TRACKS THROUGH WY. SO...PRECIP CHANCES NOT LOOKING VERY GOOD
FOR US RIGHT NOW. STILL LOOKS LIKE THE PIKES PEAK REGION AND CENTRAL
MTS N OF HGWY 50 WILL GET SOME SNOW...PERHAPS A COUPLE INCHES. BUT
ELSEWHERE...HAVE TRIMMED BACK THE LOW POPS AND WILL KEEP THEM SILENT
FOR NOW. TEMPS OVER THE PLAINS ON THU SHOULD BE MAINLY IN THE UPPER
50S-LOWER 60S.
RIDGING ON FRIDAY SHOULD MITIGATE FIRE WX CONCERNS...AS WINDS DIE
DOWN FOR A DAY OR SO. BUT IT STILL LOOKS DRY...AS DOES SATURDAY WHEN
SWRLY FLOW PICKS UP ONCE AGAIN AND LEADS TO MORE FIRE WX CONCERNS.
NEXT SYSTEM IS STILL BEING HANDLED QUITE DIFFERENTLY BY THE GLOBAL
MODELS. MODELS ARE ALL SHOWING A SPLIT SYSTEM...BUT THE GFS HAS A
WEAKER CUTOFF...AND BROAD DISORGANIZED CUTOFF LOW OVER NRN CO AND WY
BY MONDAY. THE ECMWF HAS A MORE ZONAL PATTERN TO OUR NORTH...BUT
KEEPS THE SRN CUTOFF SYSTEM TOO FAR SOUTH TO IMPACT OUR AREA.
NEITHER 12Z SOLUTION WOULD BRING US MUCH PRECIPITATION...WE JUST CAN
NOT GET A BREAK FROM THIS DISORGANIZED PATTERN! STILL...IT LOOKS
LIKE A CONTINUED PERIOD OF UNSETTLED WEATHER WITH SHOWERS PROBABLE
FOR AT LEAST THE MTN AREAS. ROSE
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1112 PM MDT MON APR 6 2015
VFR CONDITIONS IN COMBINATION WITH GUSTY WINDS AT TIMES ARE
ANTICIPATED OVER THE KALS...KCOS AND KPUB TAF SITES INTO TUESDAY
EVENING AS DRY SOUTHWESTERLY UPPER FLOW REMAINS OVER THE REGION.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY
EVENING FOR COZ222-224>237.
RED FLAG WARNING FROM NOON TO 8 PM MDT TUESDAY FOR COZ220>230-
233.
&&
$$
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
358 AM EDT TUE APR 7 2015
.SYNOPSIS...
A BACKDOOR COLD FRONT WILL PROGRESS SOUTHWARD THROUGH THE AREA
TODAY. THIS FRONT WILL STAY TO OUR SOUTH TONIGHT THROUGH THURSDAY.
MEANWHILE, HIGH PRESSURE BUILDING IN FROM EASTERN CANADA WILL BE
ACCOMPANIED BY PERSISTENT ONSHORE FLOW IN THE MID-ATLANTIC REGION.
THE SAME FRONTAL BOUNDARY IS EXPECTED TO RETURN BACK NORTHWARD AS A
WARM FRONT ON FRIDAY BEFORE A COLD FRONT MOVES THROUGH FRIDAY NIGHT.
HIGH PRESSURE BUILDS INTO THE REGION THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A CDFNT WILL WORK ITS WAY SWD OVER THE REGION THRU THE COURSE OF
THE DAY TODAY AND BRING SHOWERS WITH IT.
LATEST RADAR SHOWED SOME PRECIP W OF BALTIMORE WITH SOME DEVELOPING
IN SRN NJ AND ADDITIONAL PRECIP OVER THE POCONOS. HRRR GUID IS
ONLY PICKING UP THE LARGER AREA W OF BALTIMORE REALLY WELL AND WANTS
TO LESSEN IT/DISSIPATE IT AS IT MOVES EWD. HRRR STILL WANTS TO HOLD
OFF THE BULK OF THE PRECIP, AS DO THE REST OF THE MDLS UNTIL AFTER
DAYBREAK.
STLT IMAGERY AND SFC OBS STILL HAVE HIGH TO MID LEVEL CLOUDS AND THE
AMS IS RELATIVELY DRY, SO HAVE GONE WITH THE TREND AND HAVE PLACED
SOME LOW POPS ERLY WAND HIGHER POPS A BIT LATER THAN THE PREV FCST.
OVERALL, TODAY LOOKS TO BE A CLOUDY AND WARM DAY WITH GENLY PDS OF
LIGHT RAIN.
THE WIND WILL START OFF SWLY IN THE MRNG AND BECOME MORE NELY LATER
IN THE DAY, DEPENDING ON LOCATION, AS THE FRONT PASSES. ONCE THE
WIND SHIFTS, YOU WILL KNOW IT AS SW WIND IS GENLY WARM AND NE IS
NOT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
THE RAIN STAYS WITH US EARLY TONIGHT BEFORE ENDING. IT WILL
LIKELY BECOME MORE STRATIFORM AND COULD EVEN BE MORE OF A DRIZZLE.
IT LOOKS TO BE A FAIRLY DREARY NIGHT WITH A NE WIND AND WHATEVER
IS FALLING FROM THE SKY. PRECIP SHUD COME TO AN END LATE.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
A STRONG (BETWEEN 1035-1040 MB) SURFACE HIGH WILL BUILD EASTWARD
ACROSS QUEBEC ON WEDNESDAY. A CLASSIC CAD SETUP WILL BE IN PLACE
FOR THE MIDWEEK, INDICATIVE BY THE U-SHAPED MSLP PATTERN AS HIGH
PRESSURE RIDGES SOUTHWARD DOWN INTO MID-ATLANTIC REGION. FORECAST
MODEL SOUNDINGS PICK UP ON THE SHALLOW WEDGE OF COLD AIR NEAR THE
SURFACE THAT REMAINS TRAPPED ON THE EASTERN SIDE OF THE
APPALACHIANS. IN ADDITION TO THE BELOW NORMAL TEMPS, THIS PATTERN
WILL RESULT IN PLENTY OF CLOUDS ALONG WITH PERIODS OF LIGHT RAIN
AND DRIZZLE WEDNESDAY AND THURSDAY.
SOME OF THE COLDER MODEL GUIDANCE IS SHOWING THE POTENTIAL FOR
LIGHT FREEZING RAIN IN NORTHEAST PA AND FAR NORTHWEST NJ OVERNIGHT
WEDNESDAY INTO THE EARLY MORNING THURSDAY. THERE IS STILL
UNCERTAINTY THAT TEMPS FALL BELOW FREEZING AND THAT ICE ACCRETION
WOULD OCCUR IN THESE NORTHERN MOST ZONES. DENSE CLOUD COVER
SHOULD MINIMIZE RADIATIONAL COOLING AND CAA WILL BE ABSENT UNDER
AN EAST TO SOUTHEAST FLOW IN THE BOUNDARY LAYER. EVEN THE COLDEST
GUIDANCE HAS TEMPS HOVERING AROUND 32 DEGREES, WHICH WOULD BE
DIFFICULT FOR ICE TO ACCRETE ON ANYTHING OTHER THAN ELEVATED
SURFACES (TREES/ROAD SIGNS/POWERLINES) GIVEN HOW WARM THE GROUND
IS. NEVERTHELESS, THE NAM AND ABOUT HALF OF THE SREF MEMBERS
SUPPORT FREEZING RAIN ALONG AND NORTH OF I-80 LATE WEDNESDAY
NIGHT, SO IT WOULDN`T BE PRUDENT TO COMPLETELY DISMISS THE
POTENTIAL OF A LIGHT GLAZE.
SOUTHWEST FLOW WILL STRENGTHEN AHEAD OF AN APPROACHING COLD FRONT ON
FRIDAY. A MAJORITY OF THE LATEST MODEL GUIDANCE SHOWS THE CAD WEDGE
ERODING AND THE PRE-FRONTAL WARM SECTOR BECOMING ESTABLISHED OVER
THE FORECAST AREA. AS STATED BY YESTERDAY`S DAY SHIFT FORECASTER,
THE MODELS TEND TO BE TOO AGGRESSIVE WITH THE PROGRESSION OF WARM
FRONTS THIS TIME OF YEAR DUE TO THE PRESENCE OF THE COLD OCEAN
TEMPS. IN SOME CASES, THE CAD WEDGE DOES NOT ERODE UNTIL AFTER THE
COLD FROPA WHICH WOULDN`T BE UNTIL FRIDAY EVENING. THERE WILL
LIKELY BE A NOTICEABLE NORTH TO SOUTH TEMP GRADIENT ON FRIDAY
WITH HIGHS IN THE 70S SOUTH OF THE WARM FRONT AND 60S FARTHER
NORTH (EXCEPT 50S IN THE POCONOS/NORTHWEST NJ WHERE THE HILLY
TERRAIN WILL MAKE IT MORE DIFFICULT TO SCOUR OUT THE COLD). THERE
MAY BE AN OPPORTUNITY FOR THUNDERSTORMS TO DEVELOP IN THE WARM
SECTOR JUST AHEAD OF THE COLD FRONT DURING THE PEAK HEATING HOURS
ON FRIDAY. SPC OUTLOOK FROM YESTERDAY MORNING HAD PLACED A
PORTION OF THE DELMARVA IN A 15 PERCENT PROBABILITY FOR SEVERE
STORMS ON FRIDAY.
COOLER AIR WILL MOVE BEHIND THE COLD FRONT LATE FRIDAY NIGHT. THE
AIRMASS WILL NOT BE EXTREMELY COLD SO TEMPS SHOULD BE NEAR NORMAL
THIS WEEKEND. CANNOT RULE OUT A BRIEF SHOWER IN THE POCONOS WITH
THE PASSAGE OF AN UPPER TROUGH ON SATURDAY. OTHERWISE THE WEEKEND
SHOULD BE DRY AS HIGH PRESSURE BUILDS OVERHEAD.
HIGH PRESSURE MOVES OFFSHORE BY MONDAY. DESPITE RISING HEIGHTS
AND SOUTHERLY FLOW/WAA ALOFT, WARMING AT THE SURFACE WOULD BE
MODERATED BY THE ONSHORE FLOW FROM THE COOLER WATERS.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
VFR CONDS ARE HANGING ON LONGER THAN ANTICIPATED ERLY THIS MRNG
AND THE CURRENT FCST MAY BE TOO PESSIMISTIC. ITS PSBL THAT WE KEEP
THE VFR THRU DAYBREAK (OR EVEN LONGER IN SOME AREAS). HOWEVER, THE
OVERALL TREND IS STILL DOWNWARD LATER THIS MORNING, AS A FRONT
MOVES FROM N TO S ACRS THE AREA. CONDS WILL DROP FROM VFR TO MVFR
AND THEN TO IFR. SOME LIFR CAN NOT BE RULED OUT. ONCE CONDS DROP,
THEY WILL STAY DOWN THRU THE DAY AND INTO TONIGHT. VSBYS MAY
IMPROVE TO VFR BY MIDNIGHT OR SHORTLY THEREAFTER, BUT STILL EXPECT
THE LOW CIGS TO STICK AROUND.
WIND WILL START OUT FROM THE SW, GENLY LESS THAN 10 KTS, BUT WILL
SHIFT TO THE NE AND GUST TO AROUND 20 KT BY LATE AFTN ERLY EVE.
OUTLOOK...
WEDNESDAY THROUGH THURSDAY NIGHT...BREEZY NE WINDS WINDS WILL
SUBSIDE A BIT AFTER WEDNESDAY. THE ONSHORE FLOW WILL RESULT IN A
PROLONGED STRETCH OF LOW CLOUDS AND PERIODS OF RA/DZ. EXPECT IFR
CIGS FOR MAJORITY OF THE PERIOD BUT DO SEE SOME OPPORTUNITY FOR
BRIEF IMPROVEMENTS TO MVFR DURING THE AFTERNOON HOURS EACH DAY.
ABOVE NORMAL CONFIDENCE.
FRIDAY...IFR CIGS IN THE MORNING IMPROVE TO MVFR AND THEN VFR FROM
SOUTH TO NORTH DURING THE DAY. CONFIDENCE IN THIS IMPROVEMENT
HIGHEST IN OUR SOUTHERN TERMINALS. SW WINDS WILL BE GUSTY. SHOWERS
AND POSSIBLY A THUNDERSTORMS WITH A COLD FROPA FRIDAY AFTN/EVE.
SATURDAY...VFR AND BREEZY NW WINDS.
&&
.MARINE...
THE SCA IN EFFECT FOR ERLY THIS MRNG HAS BEEN CANCELLED AS CONDS
REMAIN BELOW CRITERIA. CONDS WILL REMAIN BELOW CRITERIA FOR TODAY
AND MOST OF TONIGHT. THE WIND WILL SHIFT FROM SW TO NE BE LATE
AFTN/ERLY EVE N AND OVERNIGHT S. AND WIND SPEED WILL INCREASE TO
NEAR ADVY CRITERIA BY THE END OF THE PD WITH SEAS RESPONDING IN
KIND.
OUTLOOK...
WEDNESDAY...POTENTIAL FOR GALES, PARTICULARLY IN THE COASTAL
WATERS ADJACENT TO CENTRAL NJ AND DURING THE MORNING HOURS. A GALE
WATCH WAS ISSUED FOR OUR TWO NORTHERN MOST ZONES. ISSUED A SCA FOR
OUR COASTAL ZONES FARTHER SOUTH WHERE NELY WINDS WILL BE SLIGHTLY
WEAKER. WENT 1-2 FT ABOVE WAVEWATCH GUIDANCE FOR WAVE HEIGHTS
BASED ON KNOWN MODEL BIAS IN NE FLOW.
WEDNESDAY NIGHT AND THURSDAY...NELY WINDS DIMINISH BUT MAY STILL BE
NEAR 25 KT OFF THE NJ COAST. SCA STILL EXPECTED TO PERSIST FOR ALL
COASTAL ZONES WITH CHOPPY SEAS OF 5-8 FT.
FRIDAY...SWLY WINDS STRENGTHEN AND SCA CONDITIONS EXPECTED BY
AFTERNOON. 40-50 KT WINDS ARE FORECAST TO DEVELOP NOT TOO FAR ALOFT
BUT VERY WARM AIR MOVING ATOP THE COLDER WATERS DO NOT FAVOR
THESE WINDS TO MIX DOWN TO THE SURFACE.
FRIDAY NIGHT AND SATURDAY...WINDS BECOME NWLY BEHIND COLD FROPA
SHOULD GUST TO UNDER 25 KT. SEAS 4-6 FT FRIDAY NIGHT WILL SUBSIDE TO
4 FT OR LESS BY SATURDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EDT WEDNESDAY FOR
ANZ452>455.
GALE WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY AFTERNOON
FOR ANZ450-451.
&&
$$
SYNOPSIS...KLEIN
NEAR TERM...NIERENBERG
SHORT TERM...NIERENBERG
LONG TERM...KLEIN
AVIATION...KLEIN/NIERENBERG
MARINE...KLEIN/NIERENBERG
AREA FORECAST DISCUSSION
NWS MIAMI FL
144 AM EDT TUE APR 7 2015
.AVIATION...
EASTERLY WINDS AROUND 10 KNOTS WILL CONTINUE OVERNIGHT TONIGHT
ALONG THE EAST COAST...WITH LIGHT AND VARIABLE WINDS AT KAPF.
EARLIER RAINFALL AT KAPF MAY LEAD TO LOWER CIGS OVERNIGHT.
EASTERLY FLOW WILL INCREASE TO 12-15 KNOTS DURING THE DAY ON
TUESDAY. ANOTHER SUBTLE SHORTWAVE WILL MOVE SOUTHEAST ACROSS THE
PENINSULA LATE IN THE DAY ON TUESDAY...WHICH MAY LEAD TO SHOWERS
MAINLY NORTH OF KAPF. THERE WILL BE AN INCREASE IN LOW LEVEL
MOISTURE TOWARDS THE EAST COAST AROUND 00Z...AND MVFR CIGS ARE
POSSIBLE NEAR THE END OF THE TAF PERIOD.
&&
.PREV DISCUSSION... /ISSUED 830 PM EDT MON APR 6 2015/
UPDATE...
CONVERGENCE BETWEEN EASTERLIES AND THE GULF COAST SEA BREEZE,
ALONG WITH A VERY SUBTLE WAVE DROPPING SOUTHEAST FROM THE
NORTHEASTERN GULF, PROVIDED JUST ENOUGH LIFT FOR SHOWERS ALONG
INLAND COLLIER THIS EVENING, MUCH LESS THAN WHAT THE HRRR HAS
PREDICTED. THIS CLUSTER COULD MAKE IT TO PART OF NAPLES OVER THE
NEXT FEW HOURS WHILE WEAKENING. OTHERWISE, COASTAL CONVERGENCE,
MINIMAL DIRECTIONAL SHEAR THROUGH H7, AND EAST WINDS 10-15KT WILL
BE ENOUGH FOR AT LEAST SLT CHC POPS OFFSHORE AND ALONG THE ENTIRE
EAST COAST FOR THE REST OF TONIGHT.
PREV DISCUSSION... /ISSUED 742 PM EDT MON APR 6 2015/
AVIATION...
ISOLATED SHOWERS REMAIN ACROSS THE ATLANTIC WATERS EARLY THIS
EVENING. AS EASTERLY FLOW PERSISTS THROUGH THE NIGHT...SOME OF
THESE SHOWERS COULD BRIEFLY AFFECT THE EAST COAST SITES BUT NOT
CONFIDENT ENOUGH TO MENTION IN TAFS. MAINLY DRY CONDITIONS
EXPECTED ON TUESDAY WITH EASTERLY FLOW PREVAILING.
PREV DISCUSSION... /ISSUED 237 PM EDT MON APR 6 2015/
SHORT TERM (TONIGHT-WEDNESDAY NIGHT)...
THE SHORT TERM PERIOD LOOKS RATHER SUBDUED AS A MID/UPPER LEVEL
RIDGE AXIS REMAINS ACROSS THE EASTERN GULF OF MEXICO. THIS RIDGE
WILL AMPLIFY LATE TUESDAY INTO WEDNESDAY IN RESPONSE TO A STRONG
TROUGH MOVING ONTO THE NORTHERN CALIFORNIA COAST AND INTO THE
CENTRAL ROCKIES. A SURFACE HIGH PRESSURE RIDGE CURRENTLY LOCATED
ACROSS THE SOUTHEAST STATES WILL ALSO MOVE LITTLE PROVIDING SOUTH
FLORIDA WITH A GENERAL LOW LEVEL EAST TO SOUTHEAST FLOW. FORECAST
SOUNDINGS SUGGEST THAT THIS PATTERN WILL BE FAVORABLE FOR A FEW
ATLANTIC SHOWERS TO MOVE ONSHORE ALONG THE SOUTHEAST COAST THROUGH
THIS PERIOD WITH A FEW AFTERNOON SHOWERS OVER THE INTERIOR AND WEST
COAST.
LONG TERM (THURSDAY-MONDAY)...
THE AMPLIFIED MID LEVEL RIDGE WILL CONTINUE THROUGH FRIDAY AND THEN
WEAKEN AND SHIFT BACK TO THE SOUTH OVER THE WEEKEND AS A POTENT
TROUGH MOVES THROUGH THE CENTRAL PLAINS. AS THIS PATTERN SHIFT
OCCURS, FORECAST SOUNDINGS SHOW SOME MOISTURE INCREASE WITH PWAT
CLIMBING TO AROUND 1.5" WHICH IS RUNNING ABOVE NORMAL FOR GOING INTO
THE MIDDLE OF APRIL. IN ADDITION, THERE WILL ALSO BE SOME
DESTABILIZATION OCCURRING AS 500MB TEMPERATURES COOL SLIGHTLY. THE
CENTRAL PLAINS TROUGH THEN LIFTS TO THE NORTHEAST EARLY NEXT WEEK
WITH THE RIDGE AMPLIFYING TO THE NORTH ONCE AGAIN.
MARINE...
AN EAST TO SOUTHEAST WIND WILL CONTINUE THROUGH THE PERIOD WITH
SEAS OF 2-4 FEET OVER THE ATLANTIC WATERS AND 1-2 FEET IN THE GULF
WATERS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 83 72 85 71 / 10 10 10 0
FORT LAUDERDALE 83 73 83 73 / 10 10 10 0
MIAMI 85 73 86 73 / 10 10 10 0
NAPLES 88 70 88 70 / 10 10 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AVIATION...84/AK
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
351 AM EDT TUE APR 7 2015
.PREV DISCUSSION... /ISSUED 946 PM EDT MON APR 6 2015/
UPDATE...
FIRST WAVE OF SHOWERS CURRENTLY MOVING INTO NE GA. A SECOND
WAVE...ASSOCIATED WITH ANOTHER SHORTWAVE OVER WESTERN AL...IS
EXPECTED TO MOVE THROUGH THE AREA THROUGH THE EARLY MORNING HOURS.
NEWER RUNS OF THE HRRR HOLD THE SECOND AREA OF SHOWERS TOGETHER AS
IT MOVES ACROSS GA. WILL GO AHEAD AND KEEP THE SLIGHT CHANCE OF
THUNDER IN THE FORECAST...BUT INSTABILITY REMAINS WEAK.
PREV DISCUSSION... /ISSUED 736 PM EDT MON APR 6 2015/
PREV DISCUSSION... /ISSUED 349 PM EDT MON APR 6 2015/
SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
A MOIST SOUTHERLY LOW LEVEL FLOW WILL CONTINUE OVER NORTH AND CENTRAL
GA THROUGH THE FORECAST PERIOD ALONG WITH A NEAR ZONAL FLOW ALOFT.
UPPER LEVEL DISTURBANCES OVER WEST TN AND SOUTH LA WILL MOVE EAST
DURING THE NEXT 24 HOURS. THESE SYNOPTIC FEATURES WILL COMBINE WITH
A WARM FRONT OVER THE GULF COAST GRADUALLY MOVING NORTH THROUGH THE
STATE TONIGHT. CONSEQUENTLY...SCATTERED SHOWERS AND THUNDERSTORMS
WILL PREVAIL LATE THIS AFTERNOON AND TONIGHT WITH RAINFALL AMOUNTS
FROM 0.25 TO 0.50 INCH. DO NOT EXPECT ANY SEVERE TSTMS WITH THE
MARGINAL INSTABILITY.
ANOTHER SHORT WAVE WILL BE PASSING OVER THE TN VALLEY ON TUESDAY
WITH THE BEST CHANCES OF TSTMS OVER EXTREME NORTH GA. HOWEVER...
DIURNAL HEATING IN THE UPPER 70S AND 80S WITH A MOIST SOUTHWEST
FLOW WILL TRIGGER SCATTERED TSTMS OVER THE REMAINDER OF NORTH AND
ALL OF CENTRAL GA. THE SHOWERS AND TSTMS WILL GRADUALLY DIMINISH
ON TUESDAY EVENING.
THE WARM AND MOIST GULF FLOW WITH THE EXPECTED CLOUD COVER WILL
HOLD MIN TEMPS TO AROUND 10 DEGREES ABOVE NORMAL TONIGHT AND TUESDAY
NIGHT. MAX TEMPS ON TUESDAY WILL BE FROM 5 TO 10 DEGREES ABOVE
NORMAL AS WELL. ACCEPTED AND MERGED MET/MAV MOS GUIDANCE FOR POPS
AND TEMPS.
16
LONG TERM /WEDNESDAY THROUGH MONDAY/...
NO MAJOR CHANGES MADE TO THE EXTENDED FORECAST. WEST TO SOUTHWEST
UPPER FLOW CONTINUING OVER THE FORECAST AREA THROUGH THE PERIOD.
SEVERAL WEAK IMPULSES CROSS THE STATE RESULTING IN A GENERALLY
UNSETTLED PATTERN. HAVE CONTINUED WITH A CHANCE OR SLIGHT CHANCE
OF SHOWERS AND THUNDERSTORMS EACH DAY MOST AREAS. THE MOST
SIGNIFICANT SYSTEM SHOULD BE THE FRONT IN THE FRIDAY NIGHT THROUGH
SATURDAY PERIOD. SOME LIKELY POPS SEEM REASONABLE ALONG THE FRONT
FRIDAY. SOME DRYING INDICATED BEHIND THE FRONT FOR SATURDAY INTO
SUNDAY. HOWEVER...WITH SOME TIMING DIFFERENCES POSSIBLE FOR THAT
FAR OUT...HAVE LEFT IN A SLIGHT CHANCE OF SHOWERS OR THUNDERSTORMS
FOR THOSE TIMES. TEMPERATURES SHOULD BE WARM THROUGH THE
WEEK...EXCEPT COOLING SOME FOR THE WEEKEND.
41/01
AVIATION...
18Z UPDATE...
VFR CEILINGS GENERALLY PREVAILED OVER NORTH AND CENTRAL GA
WITH SCATTERED SHOWERS AND TSTMS APPROACHING FROM THE WEST IN AL.
EXPECT THE SHOWERS AND TSTMS TO INCREASE OVER THE TAF SITES
THROUGH THE REMAINDER OF THE AFTERNOON AND EVENING AS A WARM
FRONT MOVES NORTH THROUGH THE STATE TONIGHT. CEILINGS WILL
GRADUALLY LOWER TO IFR/MVFR AFTER MIDNIGHT THROUGH TUESDAY
MORNING. SURFACE WINDS WILL BE SOUTHEAST BECOMING SOUTHWEST ON
TUESDAY LESS THAN 10 KTS.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE FOR CEILINGS...VSBYS AND PRECIP TIMING.
HIGH CONFIDENCE FOR WINDS.
16
&&
.AVIATION...
06Z UPDATE...
IFR CIGS EXPECTED THROUGH MID MORNING...THEN IMPROVING
CONDITIONS...WITH VFR BY LATE MORNING. SE WINDS AT 5KT OR LESS
OVERNIGHT WILL INCREASE AND SHIFT TO THE SW BY MID MORNING. WINDS
SHOULD HOVER JUST WEST OF SOUTH THROUGH THE DAY. PROB30 STILL
INCLUDED FOR -TSRA FOR THE BEST AFTERNOON CHANCES...GENERALLY
17-23Z.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM CONFIDENCE ON ALL ELEMENTS.
31
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 79 60 84 63 / 30 20 30 20
ATLANTA 77 63 83 64 / 30 20 10 10
BLAIRSVILLE 73 56 79 59 / 50 20 40 20
CARTERSVILLE 78 59 84 62 / 30 20 20 10
COLUMBUS 83 64 86 64 / 20 10 10 10
GAINESVILLE 75 60 81 62 / 40 20 30 20
MACON 83 62 86 63 / 30 20 20 10
ROME 79 58 84 61 / 40 10 20 10
PEACHTREE CITY 80 58 83 62 / 20 10 10 10
VIDALIA 82 65 85 65 / 30 20 30 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...31
LONG TERM....41
AVIATION...31
AREA FORECAST DISCUSSION
NWS TOPEKA KS
407 AM CDT Tue Apr 7 2015
.SHORT TERM...(Today and Tonight)
Issued at 407 AM CDT TUE APR 7 2015
Weak shortwave trough seen in water vapor imagery crossing
eastern KS combined with warm advection above cap to create
thunderstorms over northern MO this morning. This appears to be
moving away, but have kept small chances in far
northern/northeastern KS into the morning hours in an area of
isentropic lift above cap. Better chances expected to be to north
of forecast area over Nebraska during the day.
Short range models consistent in bringing surface low from
southwestern KS at 06Z Tuesday into northeast KS by 18Z.
Thereafter it weakens the low into an inverted trough...as lee
trough begins strengthening upstream in eastern CO. Low-level
convergence along surface trough in east central KS late this
afternoon/evening could trigger some surface based thunderstorms
if lift is sufficient to overcome considerable capping inversion.
Despite lack of large scale lifting mechanism, sufficient shear
and instability should exist for the potential of isolated severe
thunderstorms near the trough.
While evening thunderstorm chances diminish after sunset, there is
still a slight chance of elevated storms later tonight with lift up
over the boundary that remains in vicinity of northeast/east central
KS.
Temps today are particularly tricky. Position of surface boundary
and thicker cloud cover expected to hold down highs in far northern
KS while upper 70s and lower 80s expected to the south of boundary.
.LONG TERM...(Wednesday through Monday)
Issued at 407 AM CDT TUE APR 7 2015
Wednesday and Wednesday night continue to be a concern regarding
strong to severe thunderstorms. Models continue to show high
surface dewpoints capped by a strong elevated mixed layer (EML).
This sets the stage for large values of CAPE if a surface parcel
is able to break through the cap. Deep layer shear of 40 to 50 KTS
would be good enough for storms to become supercells. So there
remains a chance for severe storms with large hail, damaging winds
and tornadoes. The question is how limiting with the cap be in
storm coverage. At this point there appears to be two surface
features that may help shower and thunderstorm development. The
first is a warm front that is expected to set up across northern
KS Wednesday morning. Convergence and lift from the low level jet
could cause some elevated storms to develop mainly north of the
front. However all of the moisture seems to be trapped below the
inversion with a lot of dry air above the cap. Because of this
think chances for precip are not that great and have trended POPs
down 5 to 10 percent. The more compelling feature will be a
dryline that is progged to set up across central KS by the
afternoon hours. Models show some mass convergence along this
boundary through the afternoon as well as a modest PV anomaly
lifting out across the central plains. Thinking is this may be
enough forcing that local updrafts are able to break through the
cap. With this in mind, have kept some likely POPs across east
central KS in line with prev forecast, as most model guidance
shows the same idea of storms developing on the dry line and
moving northeast into east central KS through the evening. The
concern however is that coverage could end up being pretty
limited due to the strength of the cap and the forecast of likely
POPs may signal for more widespread storms and severe weather.
For Thursday, the models bring the main upper trough across the
region. Current model runs continue to show the deeper moisture
and instability pushing off to the east early in the day Thursday.
Hove kept some small POPs in through the day for some possible
shower activity with the upper trough axis. Otherwise we should
see cooler and dryer air move in from the northwest with winds
becoming gusty by the early afternoon. Highs are expected to be
around 60 to the lower 70s due to increasing cold air advection.
Friday and Friday night look to be dry and cool as surface ridging
passes over the region. Models show return flow setting up for
Saturday and Sunday. Think precip chances Saturday are only 20
percent due to no strong forcing progged by the models. However
with warm air advection Saturday night and a surface wave moving
through the region Sunday and Sunday night, precip chances will be
on the increase. The best forcing looks to affect the forecast
area Sunday afternoon and Sunday evening as models forecast
increasing PVA. Think any lingering precip will be moving out of
the area Monday. Temps through the weekend look to be seasonable
as models keep the really warm air across the southwest.
&&
.AVIATION...(For the 00Z TAFs through 00Z Tuesday Evening)
Issued at 647 PM CDT MON APR 6 2015
Complicated forecast leading to quite low confidence. Limiting
stratus nearly out of all terminals but easterly winds developing
should allow for redevelopment by 06Z. Guidance struggling to
various degrees but stayed closer to RAP and GFS for build down to
IFR and LLWS as jet increases. At this point convective chances in
the 04Z-14Z period look too low to include, with TOP and FOE of
more concern than MHK. Southwest winds should mix down as low
pressure moves near/just NW of terminals around 18Z for return to
VFR.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...GDP
LONG TERM...Wolters
AVIATION...65
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
400 AM CDT TUE APR 7 2015
...UPDATED SHORT TERM DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT TUE APR 7 2015
A COLD FRONT WAS SLOWLY PUSHING SOUTH ACROSS CENTRAL AND SOUTHWEST
KANSAS EARLY THIS MORNING. MOIST UPSLOPE FLOW TO THE NORTH OF THE
FRONT WAS RESULTING IN WIDESPREAD STRATUS AND FOG GENERALLY ALONG
AND NORTH OF A LINE FROM LACROSSE TO NEAR DODGE CITY THEN WEST
THROUGH GARDEN CITY AND SYRACUSE. AREAS IMMEDIATELY NORTH OF THE
FRONT WERE SEEING DENSE FOG DEVELOP. THE PAST SEVERAL RUNS OF THE
RUC13 AND HRRR HAVE BEEN INDICATING THIS AND THEY HAVE GENERALLY
TENDED TO MOVE IT SLOWLY SOUTHWARD BEFORE DISSIPATING IT AFTER
SUNRISE. WILL ISSUE A DENSE FOG ADVISORY FOR THIS AREA THROUGH
ABOUT 8 AM CDT.
THE FOG AND STRATUS SHOULD ERODE NORTHWARD THROUGH THE MORNING
HOURS WITH AREAS ALONG I-70 SCATTERING OUT EARLY THIS AFTERNOON.
FOR THE REST OF TODAYS FORECAST, HAVE ONLY MADE A FEW MINOR
ADJUSTMENTS. THE FRONT MAY MOVE A LITTLE MORE SOUTHWARD THIS
MORNING AS INDICATED BY THE SHORT TERM MODELS BUT THE SOUTHERN
PORTION OF THE FRONT SHOULD MIX OUT THROUGH THIS AFTERNOON. MOS
GUIDANCE IS PRETTY SIMILAR OVER WESTERN SECTIONS OF THE CWA BUT
DIFFERS MORE IN THE EAST WHERE THE COOLER MET MOS KEEPS HIGHS IN
THE UPPER 60S WHILE THE MAV GUIDANCE WARMS CENTRAL KANSAS INTO THE
MID 70S. GIVEN THAT THERE WILL BE STRATUS ERODING THROUGH PART OF
THE DAY, HAVE CONTINUED TO LEAN TOWARD THE COOLER GUIDANCE FOR
THAT AREA.
TONIGHT WILL SEE STRATUS REDEVELOPING ALONG WITH SOME PATCHY FOG
AND DRIZZLE ESPECIALLY IN THE WAKEENEY, HAYS AND LACROSSE AREAS.
MODEL SOUNDINGS ARE STILL SHOWING LOW LEVEL WARM ADVECTION
MAXIMIZED IN THAT AREA AROUND OR AFTER MIDNIGHT. IF ANY PARCELS
CAN GET LIFTED ENOUGH, THERE WILL BE SOME INSTABILITY ALOFT THAT
COULD SUPPORT A FEW THUNDERSTORMS. WILL LEAVE A MENTION OF ISOLATED
THUNDERSTORMS IN THAT AREA AS WELL.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 319 AM CDT TUE APR 7 2015
AN UPPER LEVEL LOW WILL BE POSITIONED OVER THE INTERMOUNTAIN WEST
WEDNESDAY THEN TREK EASTWARD INTO THE CENTRAL ROCKIES WEDNESDAY
NIGHT BEFORE SWINGING ACROSS NEBRASKA AND THE NORTHERN PLAINS
THURSDAY. AT THE SURFACE, AN AREA OF LOW PRESSURE WILL INTENSIFY
AS THE PREVIOUS FEATURE APPROACHES WITH A STALLED OUT FRONT
EXTENDING EASTWARD ACROSS SOUTHERN KANSAS. PATCHY FOG WILL BE
POSSIBLE NORTH OF THIS FRONT WHERE LIGHT WINDS AND AMPLE LOW LEVEL
MOISTURE WILL BE FOUND. THIS FOG IS ONLY EXPECTED TO LAST A COUPLE
OF HOURS AFTER SUNRISE WITH MOSTLY CLEAR SKIES EXPECTED FOR THE
REMAINDER OF THE DAY DUE TO MID LEVELS OF THE ATMOSPHERE BEING
DRY. VERY DRY AIR WILL BE FILTERED IN FROM THE SOUTHWEST SOUTH OF
THIS FRONT LEADING TO A DRYLINE ACROSS FAR SOUTHWESTERN KANSAS. IN
ADDITION, A FEW THUNDERSTORMS COULD FORM AHEAD OF THIS DRYLINE
DURING THE LATE AFTERNOON INTO THE EARLY EVENING. HOWEVER, ANY
CONVECTION THAT DOES FORM WILL QUICKLY MOVE EASTWARD INTO
WICHITA`S CWA. THE AREA OF LOW PRESSURE WILL QUICKLY MOVE EASTWARD
ACROSS KANSAS WEDNESDAY NIGHT WITH A COOLER NORTHWESTERLY WINDS
FELT BEHIND IT. MOISTURE WILL WRAP AROUND THIS SYSTEM BRINGING
SCATTERED SHOWERS ACROSS PORTIONS OF THE PLAINS. HOWEVER, MOST OF
THE LIFT WILL BE NORTH OF THE AREA WITH ONLY A SLIGHT CHANCE OF
SHOWERS ACROSS THE I-70 CORRIDOR EARLY THURSDAY MORNING.
A QUIET PATTERN WILL BE IN PLACE THURSDAY NIGHT THROUGH FRIDAY AS
HIGH PRESSURE BUILDS INTO THE AREA THURSDAY NIGHT THEN TREKS
SOUTHEAST OF THE AREA FRIDAY. AN AREA OF LOW PRESSURE WILL ALSO
DEVELOP ACROSS EASTERN COLORADO FRIDAY DUE TO A WEAK SHORTWAVE
MOVING THROUGH THE NORTHERN ROCKIES. SKIES LOOK TO BE MOSTLY CLEAR
DURING THIS PERIOD WITH WINDS BECOMING SOUTHERLY BY FRIDAY
AFTERNOON.
ATTENTION THEN FOCUSES ON THE WEEKEND AS AN UPPER LEVEL SHORTWAVE
INTENSIFIES ABOVE THE DESERT SOUTHWEST THEN TRACKS EASTWARD ACROSS
THE SOUTHERN ROCKIES AND SOUTHERN PLAINS. A LARGE DOME OF HIGH
PRESSURE WILL BE IN PLACE ACROSS THE EASTERN UNITED STATES AS THIS
FEATURE APPROACHES ALLOWING GULF MOISTURE TO BE PUSHED NORTH INTO
THE PLAINS. A FEW THUNDERSTORMS WILL BE POSSIBLE OVER THE WEEKEND
WITH INCREASED CLOUD COVER. A QUIET PATTERN THEN RETURNS EARLY
NEXT WEEK AS AN UPPER LEVEL RIDGE BUILDS ACROSS THE SOUTHWEST
UNITED STATES.
AS FOR TEMPERATURES, HIGHS WEDNESDAY LOOK TO RANGE FROM THE LOWER
70S NORTH OF THE FRONT TO UPPER 80S ACROSS THE KS/OK BORDER WHERE
THE VERY DRY AIR WILL BE IN PLACE. LOWS WEDNESDAY NIGHT LOOK TO
RANGE FROM AROUND 40 DEGREES ACROSS WEST CENTRAL KANSAS TO LOWER
50S ACROSS SOUTH CENTRAL KANSAS. COOLER TEMPERATURES ARE EXPECTED
BEHIND THE FRONT THURSDAY INTO FRIDAY WITH HIGHS IN THE 60S. LOWS
THURSDAY NIGHT ARE FORECASTED TO DIP INTO THE 30S WITH LOWER 40S
EXPECTED FRIDAY NIGHT. HIGHS REBOUND INTO THE 70S THIS WEEKEND
WITH LOWS IN THE 40S TO LOWER 50S. HIGHS MONDAY THEN LOOK TO BE
AROUND 70 DEGREES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1225 AM CDT TUE APR 7 2015
A WEAK COLD FRONT WILL MOVE THROUGH THE DODGE CITY AND GARDEN CITY
TERMINALS BY THE BEGINNING OF THIS TAF PERIOD. WINDS WILL
INITIALLY BE FROM THE NORTHEAST BEFORE GRADUALLY SHIFTING TO THE
NORTH LATER TONIGHT. WE EXPECT TO SEE CEILINGS AND VISIBILITIES
DROPPING INTO THE IFR TO OCCASIONALLY LIFR CATEGORY FOR A PERIOD
OF TIME BEHIND THE FRONT THROUGH THE EARLY MORNING HOURS. CONDITIONS
SHOULD IMPROVE TO VFR SHORTLY AFTER SUNRISE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 80 49 84 46 / 0 10 10 10
GCK 79 46 81 42 / 0 10 10 10
EHA 83 47 81 43 / 0 10 0 10
LBL 85 46 85 44 / 0 10 0 0
HYS 70 46 69 46 / 10 20 20 20
P28 85 55 88 53 / 10 10 20 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 8 AM CDT /7 AM MDT/ THIS MORNING FOR
KSZ045-046-061>065-075>079.
FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR KSZ061>063-074>078-080-081-084>090.
&&
$$
SHORT TERM...GERARD
LONG TERM...HOVORKA_42
AVIATION...GERARD
AREA FORECAST DISCUSSION
NWS WICHITA KS
334 AM CDT TUE APR 7 2015
.SYNOPSIS...
ISSUED AT 334 AM CDT TUE APR 7 2015
IN THE UPPER LEVELS...WE CURRENTLY HAVE A STRONG UPPER LOW APPROACHING
NORTHERN CA WITH SW FLOW ALOFT SPREAD OVER THE ROCKIES INTO THE
PLAINS. AT THE SURFACE...LOW PRESSURE IS CENTERED OVER WEST-
CENTRAL KS/FAR EASTERN CO WITH A STATIONARY FRONT STRETCHING FROM
THE LOW PRESSURE ACROSS NORTHEAST KS AND CENTRAL MO. RICH LOW
LEVEL MOISTURE CONTINUES TO STREAM NORTH FROM THE GULF WITH
WIDESPREAD UPPER 60S DEW POINTS ACROSS EAST TX.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 334 AM CDT TUE APR 7 2015
THE UPPER LOW WILL SLOWLY TRACK EAST TODAY AND WILL BE APPROACHING
THE CENTRAL GREAT BASIN TONIGHT. A DRY LINE WILL MIX EAST TODAY
ACROSS WESTERN OK/TX WITH THE SYNOPTIC FRONT TAKING UP POSITION
FROM NE TO SW ACROSS SE KS AND INTO NORTH CENTRAL OK. THE MAIN
QUESTION WILL BE WHETHER STORMS CAN DEVELOP ALONG THESE BOUNDARIES
LATE THIS AFTERNOON/EVENING. THE NAM AND GFS HAVE BOTH BACKED OFF
ON THE AMOUNT OF CONVERGENCE OVER SE KS WITH THE RAP MUCH MORE
AGGRESSIVE IN BREAKING OUT CONVECTION LATE THIS AFTERNOON. CURRENT
THINKING IS THAT THERE IS STILL A CHANCE A STORM OR TWO COULD
DEVELOP LATE THIS AFTERNOON OVER SE KS WITH ANOTHER CHANCE FOR
ELEVATED STORMS AFTER DARK IN THIS SAME LOCATION ASSOCIATED WITH
AN INCREASE IN 850-700MB MOISTURE TRANSPORT. ANY STORM THAT
DEVELOPS EITHER THIS AFTERNOON OR TONIGHT WILL HAVE A GOOD CHANCE
TO BE SEVERE. THE TORNADO THREAT WILL BE CONDITIONAL ON STORMS
BEING ABLE TO DEVELOP IN THE 22-01Z TIME FRAME SO IT COULD STILL
BE ROOTED IN THE BOUNDARY LAYER AND THUS TAKE ADVANTAGE OF THE LOW
LEVEL SHEAR.
SIGNIFICANT SEVERE STORMS STILL LOOK POSSIBLE WED
AFTERNOON/EVENING ACROSS MAINLY SOUTH CENTRAL KS. QUITE
CONSIDERABLE DIFFERENCES HAVE SHOWN UP BETWEEN THE GFS AND NAM.
THE NAM HAS THE STATIONARY FRONT MUCH FURTHER SOUTH COMPARED TO
THE GFS WHICH WOULD LIMIT SEVERE CHANCES OVER MUCH OF CENTRAL KS.
THE NAM DOES HAVE SOME SUPPORT FROM THE 00Z ECMWF. THE MAIN
QUESTION REGARDING STORMS WED AFTERNOON/EVENING ISN`T HOW SEVERE
THEY WILL BE IF THEY DEVELOP...IT IS HOW MANY STORMS ARE ABLE TO
DEVELOP. FEEL THAT WITH SOME SHORTWAVE ENERGY FINALLY KICKING OUT
OF THE ROCKIES...AT LEAST A FEW STORMS WILL DEVELOP WED
AFTERNOON/EVENING...ESPECIALLY NEAR THE TRIPLE POINT WHERE
CONVERGENCE WILL BE MAXIMIZED. WITH 0-6KM SHEAR IN THE 45-55KT
RANGE AND CAPE IN THE 2500-3000J/KG RANGE...ANY STORMS THAT
DEVELOP WILL QUICKLY BECOME SEVERE. STORMS SHOULD BE ABLE TO STAY ISOLATED
AS THEY MOVE OFF THE DRYLINE WITH THE DEEP LAYER SHEAR
PERPENDICULAR TO THE BOUNDARY. THE NAM HAS QUITE A BIT MORE 0-3KM
CAPE COMPARED TO THE GFS BUT FEEL IT MAYBE CLOSER TO REALITY AS IT
SURPRISINGLY LOOKS TO HAVE A SLIGHTLY BETTER HANDLE ON THE LOW
LEVEL MOISTURE.
STORMS WILL TRACK EAST WED NIGHT AND AFFECT AREAS EAST OF I-135.
THE UPPER SHORTWAVE WILL QUICKLY PUSH EAST AND WILL BE OVER
WESTERN IA BY THU EVENING. THIS WILL ALLOW THE FRONT TO QUICKLY
SLIDE EAST WITH ONLY FAR SE KS HAVING A SHOT AT STORMS THU
MORNING. MEANWHILE...CENTRAL KS MAY GET IN ON SOME OF THE WARP
AROUND SHOWERS ASSOCIATED WITH THIS SYSTEM ON THU.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 334 AM CDT TUE APR 7 2015
HIGH PRESSURE IS EXPECTED TO SLIDE OVER THE PLAINS FOR FRI
ALLOWING FOR CLEAR SKIES AND TEMPS CLOSER TO SEASONAL NORMALS. AN
ACTIVE SPLIT FLOW PATTERN LOOKS TO COMMENCE FOR THE WEEKEND AS A
SERIES OF SHORTWAVES MOVE OUT OF THE ROCKIES AND ACROSS THE
PLAINS. THE IMPULSE THAT SHOULD HAVE AN IMPACT ON OUR FORECAST
AREA WILL LIFT OUT OF THE DESERT SW SAT AND INTO CENTRAL KS FOR
SUN WITH A MORE SIGNIFICANT TROUGH SWINGING ACROSS THE PLAINS FOR
MON. AT THIS TIME THE SAT NIGHT-SUN NIGHT TIME FRAME LOOKS TO HAVE
THE BEST CHANCES AT SHOWERS AND STORMS.
LAWSON
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1127 PM CDT MON APR 6 2015
CLEAR SKIES HAVE RETURNED TO THE AREA THIS EVENING...HOWEVER LOW
CIGS WITH VISIBILITIES IN THE 3-5 RANGE ARE ANTICIPATED AFTER
08-10Z ACROSS BOTH CENTRAL KANSAS AND SOUTHEAST KANSAS. IFR/LIFR
CIGS CONTINUE TO EXPAND NORTH OF THE STATIONARY FRONT AND ARE
EXPECTED TO IMPACT THE KRSL AND KSLN AREAS FROM 08-10Z THROUGH AT
LEAST 15Z BEFORE AN INCREASING WESTERLY COMPONENT ADVECTS DRIER
AIR ACROSS THE AREA. FURTHER SOUTH AND EAST...MID AND UPPER 60
DEWPOINTS HAVE RESULTED IN NARROW T/TD SPREADS AND AREAS OF FOG
AND LOW CIGS ARE EXPECTED TO REDEVELOP LATE TONIGHT/EARLY TUE.
&&
.FIRE WEATHER...
ISSUED AT 310 PM CDT MON APR 6 2015
THE MOST CRITICAL FIRE WEATHER DAY THROUGH THIS FORECAST PACKAGE
LOOKS TO BE THURSDAY.
EVEN WITH RICH LOW LEVEL MOISTURE...VERY HIGH FIRE DANGER WILL BE
IN PLACE ACROSS SOUTH CENTRAL AND PARTS OF SE KS WED DUE TO
STRONG SOUTH WINDS. WINDS WILL FLIP AROUND TO THE WEST AND
NORTHWEST ON THU AT SPEEDS IN THE 20-30 MPH RANGE BY AFTERNOON
HOURS. RH`S THU AFTERNOON WILL BE IN THE 30-40% RANGE.
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 83 64 84 55 / 10 10 30 30
HUTCHINSON 80 56 80 51 / 0 10 30 20
NEWTON 83 58 81 53 / 10 10 30 30
ELDORADO 84 65 82 59 / 10 20 30 40
WINFIELD-KWLD 85 65 83 60 / 10 10 30 30
RUSSELL 71 48 70 47 / 10 10 20 20
GREAT BEND 75 50 74 47 / 10 10 20 10
SALINA 75 52 73 50 / 10 10 30 30
MCPHERSON 79 55 77 50 / 10 10 30 30
COFFEYVILLE 83 65 81 65 / 10 20 30 40
CHANUTE 83 65 80 64 / 10 30 30 50
IOLA 83 64 79 63 / 10 30 30 50
PARSONS-KPPF 83 65 81 64 / 10 20 30 50
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
340 AM EDT TUE APR 7 2015
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 340 AM EDT TUE APR 7 2015
06Z SFC ANALYSIS SHOWS LOW PRESSURE OVER THE CENTRAL PLAINS WITH A
WARM FRONT SLUNG EAST...RUNNING INTO THE OHIO VALLEY BEFORE
BECOMING A STATIONARY BOUNDARY JUST NORTH OF EASTERN KENTUCKY.
THIS PLACES THE CWA IN A WARM AND MOIST ENVIRONMENT AS SOUTH WINDS
SUPPORT PWS APPROACHING 1.5 INCHES. JUST NOW A FEW SHOWERS ARE
STARTING TO POP OVER THE SOUTHERN PARTS OF THE AREA AFTER A
RELATIVELY QUIET EVENING AND START TO THE NIGHT. ADDITIONAL
CONVECTION TO THE WEST IS PUSHING EAST JUST SOUTH OF THE WARM
FRONT...CURRENTLY MOVING THROUGH NORTHWESTERN KENTUCKY AND
SOUTHERN ILLINOIS/INDIANA. UNDER MOSTLY CLOUDY SKIES OVERNIGHT...
MOST OF EASTERN KENTUCKY IS SEEING TEMPERATURES FROM 55 TO 60
DEGREES WITH SOME EASTERN VALLEYS SLIGHTLY COOLER AND WARMER
CONDITIONS IN THE FAR SOUTHWEST. DEWPOINTS...MEANWHILE...HAVE
COME UP INTO THE 50S FOR THE AREA...A DRAMATIC REVERSAL OF THIS
PAST WEEKEND/S DRYNESS.
THE MODELS ARE IN FAIRLY GOOD AGREEMENT ALOFT THROUGH THE SHORT
TERM AS A SERIES OF WEAK TO MODERATE WAVES PASS THROUGH THE OHIO
VALLEY IN BROAD...SLIGHTLY SOUTHWEST...FLOW ON THE NORTHERN
FRINGE OF THE FLAT SOUTHEAST RIDGE. EACH MODEL HAS A SLIGHTLY
DIFFERENT HANDLE ON THE TIMING AND TRACK OF THESE WAVES LOWERING
CONFIDENCE IN ANY PARTICULAR SOLUTION. NEVERTHELESS...THE ENERGY
WILL BE THERE...ALONG WITH PLENTY OF FUEL IN THE FORM OF HEAT AND
HUMIDITY...FOR CONVECTIVE DEVELOPMENT BASED MORE ON THESE MID
LEVEL RIPPLES THAN STRICTLY THE DIURNAL CYCLE. GIVEN THE SMALL
NATURE OF THE FEATURES THAT WILL DRIVE THE CONVECTION OVER THE
NEXT COUPLE OF DAYS HAVE RELIED MORE CLOSELY ON THE HIGHER
RESOLUTION HRRR AND NAM12 FOR THE WEATHER DETAILS.
SENSIBLE WEATHER WILL FEATURE AN UNSEASONABLY WARM AND HUMID
PERIOD WITH OCCASIONAL ROUNDS OF SHOWERS AND THUNDERSTORMS
EXPECTED DUE TO EASTERN KENTUCKY/S POSITION SOUTH OF A STALLED
FRONTAL BOUNDARY TO THE NORTH AND IMPULSES PASSING THROUGH FROM
ALOFT. THE FIRST OF THESE WILL PASS THIS MORNING WITH A ROUND OF
CONVECTION EXPECTED FOLLOWED BY A POTENTIAL FOR ANOTHER LATE THIS
AFTERNOON AND INTO THE EVENING. THE NAM12 WOULD THEN HAVE A LULL
UNTIL DAYTIME WEDNESDAY WHEN ANOTHER WAVE IS EXPECTED TO DEVELOP
AND PASS OVER THE STATE. SEVERE WEATHER WILL BE A POSSIBILITY
TODAY WITH EITHER OF THESE CLUSTERS DEPENDING ON UPSCALE GROWTH
AND...FOR THE LATTER...SFC HEATING BETWEEN SYSTEMS. GIVEN THE
RELATIVELY HIGH PWS...HEAVY RAIN WILL BE A POSSIBILITY AS WELL AND
MAY PRIME THE AREA FOR LOCALIZED FLOOD CONCERNS BEFORE THE FRONTAL
STRUCTURE MOVES OUT OF THE REGION AT WEEK/S END. WILL HIGHLIGHT
BOTH THE SVR AND HEAVY RAIN CONCERNS IN THE FORTHCOMING HWO.
USED THE SHORTBLEND COMPOSITE MODEL AS A STARTING POINT FOR THE
WINDS/T/TD GRIDS THROUGH THE FIRST 18-24 HOURS AND THE SUPERBLEND
THEREAFTER. DID MAKE SOME MINOR ADJUSTMENTS BASED ON TERRAIN FOR
TONIGHT/S TEMPERATURES. AS FOR POPS...ENDED UP CLOSEST TO THE MET
VALUES TODAY AND TONIGHT...BUT HIGHER FOR MIDDAY WEDNESDAY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 335 AM EDT TUE APR 7 2015
MULTIPLE WAVES WILL CONTINUE TO RIDE UP AND ALONG A RIDGING PATTERN
ACROSS THE EASTERN CONUS THROUGH THE SHORT TERM AND TO START OUT THE
EXTENDED PORTION OF THE FORECAST. MEANWHILE A STRONG SHORTWAVE OVER
THE ROCKIES WILL BEGIN TO SHIFT EASTWARD BY 0Z THURSDAY...CREATING
LONGWAVE TROUGHING OVER THE WESTERN CONUS. EXPECT THIS SHORTWAVE TO
CONTINUE ON ITS TREK EAST AND NORTHEASTWARD THROUGH THE DAY THURSDAY
AND INTO THE DAY FRIDAY...WITH DECREASING HEIGHTS EXPECTED ACROSS
THE OHIO RIVER VALLEY DURING THIS TIME.
AT THE SURFACE...KY WILL FIND ITSELF UNDER THE INFLUENCE OF A
STALLED WARM FRONT WEDNESDAY NIGHT INTO THURSDAY MORNING...WHICH
WILL LIKELY BE POSITIONED ACROSS THE NORTHERN PORTION OF THE CWA.
THIS WILL RESULT IN CONTINUED SHOWERS AND THUNDERSTORMS...ESPECIALLY
ACROSS THE NORTHERN HALF OF THE STATE. TO OUR EAST...A SURFACE LOW
WILL CONTINUE TO DEVELOP BELOW AND JUST AHEAD OF THE ABOVE MENTIONED
SHORTWAVE...AND FOLLOW ITS TRACK NORTHEASTWARD THROUGH THE DAY
THURSDAY. BY 0Z FRIDAY...THE WARM FRONT WILL SHIFT EAST AND ENABLE A
STRONG COLD FRONT...CONNECTED TO THIS LOW PRESSURE SYSTEM...TO PUSH
FROM WEST TO EAST ACROSS KY. GIVEN THE LATEST GFS FORECAST...THE
BOUNDARY SHOULD ENTER INTO EASTERN KY SOMETIME FRIDAY
AFTERNOON...ENHANCING SHOWER AND THUNDERSTORM ACTIVITY THROUGH THE
MORNING JUST AHEAD OF THE FRONT...AND EXIT EAST OF THE STATE BETWEEN
21Z FRIDAY AND 0Z SATURDAY. ONCE IT DOES...KY WILL BE IN A MORE
ZONAL UPPER LEVEL FLOW WITH SURFACE HIGH PRESSURE BUILDING ACROSS
THE STATE. SURFACE WINDS WILL ONCE AGAIN BECOME MORE
NORTHERLY...CAUSING TEMPERATURES TO DROP BACK INTO THE 40S OVERNIGHT
FRIDAY NIGHT/SATURDAY MORNING...AND IN THE MID 60S BY SATURDAY
AFTERNOON.
EXPECT THIS HIGH PRESSURE TO KEEP DRY WEATHER IN PLAY THROUGH MUCH
OF THE WEEKEND...WITH TEMPERATURES EXPECTED TO REBOUND BACK INTO THE
LOW 70S BY MONDAY. BY THIS TIME...A LOW PRESSURE SYSTEM OVER THE
SOUTHERN PLAINS WILL MOVE NE ONCE MORE AND PUSH A WARM FRONT
NORTHWARD INTO THE REGION...ALLOWING UNSTABLE WARM GULF MOISTURE TO
FLOW BACK INTO THE CWA AND ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS TO DEVELOP LATE SUNDAY AND SUNDAY NIGHT. THIS WILL BE
ENHANCED AS THE FOLLOWING COLD FRONT BEGINS FROM WEST TO EAST ACROSS
THE STATE ONCE MORE DURING THE DAY MONDAY AND MONDAY NIGHT. EXACT
TIMING OF THIS FRONTAL PASSAGE...AS WELL AS THE ONSET AND STRENGTH OF
THE PRECIPITATION ARE STILL FAR ENOUGH OUT IN THE FORECAST THAT
RELYING ON A MODEL BLEND WAS THE METHOD OF CHOICE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 210 AM EDT TUE APR 7 2015
THE LATEST HRRR AND NAM12 HOLD OFF ON ANY SIGNIFICANT PCPN MOVING
INTO EAST KENTUCKY UNTIL CLOSER TO 12Z. THIS LINES UP WELL WITH A
CLUSTER OF SHOWERS AND THUNDERSTORMS NOW MOVING THROUGH SOUTHERN
ILLINOIS...INDIANA AND NORTHWEST KENTUCKY. MVFR CIGS WILL BE THE
RULE FOR MOST OF THE AREA THROUGH THE TAF PERIOD AS THIS INITIAL
WAVE APPROACHES AND PASSES THROUGH THIS MORNING FOLLOWED BY
ANOTHER POSSIBLE IMPULSE LATER THIS EVENING WITH ADDITIONAL LOW
CIGS AND SHOWERS/STORMS. IN THE HEAVIER CONVECTION...MVFR VIS
WILL BE A GOOD BET WITH OCCASIONAL IFR VIS OR CIGS IN STORMS.
THROUGH THE TAF PERIOD...WINDS WILL GENERALLY BE FROM THE SOUTH AT
5 TO 10 KTS...EXCEPT IN HIGHER GUSTS IN STORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
209 AM EDT TUE APR 7 2015
.UPDATE...
ISSUED AT 145 AM EDT TUE APR 7 2015
DID A QUICK UPDATE TO THE GRIDS MAINLY TO SLOW DOWN THE ARRIVAL OF
ANY SIGNIFICANT PCPN UNTIL CLOSER TOWARD DAWN. ALSO UPDATED THE
SKY COVER AND T/TD GRIDS PER THE LATEST SHORTBLEND GUIDANCE...
OBS...AND TRENDS. THESE HAVE BEEN SENT TO THE THE NDFD AND WEB
SERVERS.
UPDATE ISSUED AT 1051 PM EDT MON APR 6 2015
THE AREA OF SHOWERS THAT AFFECTED SOUTHERN PORTIONS OF THE CWA
HAVE MOVED EAST OF THE REGION THIS HOUR. WSR-88D RADAR SHOWS A
AREA OF SHOWERS ACROSS CENTRAL KY MOVING SOUTH AND EAST...HOWEVER
THIS AREA OF SHOWERS HAS CONTINUED TO WANE OVER THE PAST FEW
HOURS. GIVEN THIS FELT IT JUSTIFIED DROPPING POPS FOR PORTIONS OF
THE NIGHT. ALL EYES THEN TURN TO THE WEST...WHILE A SUBTLE UPPER
LEVEL WAVE MOVES THROUGH THE FLOW AS WE MOVE THROUGH THE NIGHT
INTO EARLY TOMORROW. WHILE IT SHOULD BE SAID THAT THE GUIDANCE
CONTINUES TO STRUGGLE TONIGHT...THE HRRR HAS COME BACK TO
PROGRESSING AN AREA OF PRECIP ALONG THE WESTERN CWA BORDER TOWARD
THE DAWN HOURS TUESDAY. DID STICK CLOSE TO PREVIOUS FORECAST FOR
THAT PERIOD...GIVEN CONTINUED UNCERTAINTY ON NEXT AREA OF PRECIP
AND STILL LOOKED REASONABLE BASED ON LATEST MESO MODEL GUIDANCE.
ALSO UPDATED GRIDS TO MATCH LATEST OBS AND TRENDS.
UPDATE ISSUED AT 832 PM EDT MON APR 6 2015
WSR-88D CONTINUES TO SHOW AN AREA OF SHOWERS MOVING EAST ACROSS
SOUTHEAST PORTIONS OF THE CWA THIS EVENING. HEAVIER SHOWERS HAVE
GENERALLY BEEN ALONG AND NEAR THE TN/VA BORDER THIS AFTERNOON AND
EVENING. OTHERWISE MOST AREAS ARE CONTINUING TO SEE A PASSING
LIGHT SHOWER FROM TIME TO TIME. EVEN THOUGH MUCH OF THIS HAS BEEN
SHOWERS HAVE KEPT THE MENTION OF THUNDER GIVEN THAT WE CONTINUE TO
BE IN A GENERALLY MOIST AND UNSTABLE ENVIRONMENT. THERE CONTINUES
TO BE A FAIR AMOUNT OF UNCERTAINTY WHERE AND WHEN THE BETTER
SHOWERS AND THUNDERSTORMS SETUP ACROSS THE REGION OVER THE NEXT 24
HOURS. THIS DISAGREEMENT IS ALSO PREVALENT IN MUCH OF THE MESO
MODEL GUIDANCE AS WELL. EITHER WAY THE NEXT BEST WAVE LOOKS TO
MOVE THROUGH...AS WE MOVE INTO TUESDAY MORNING. GIVEN THIS THE
CURRENT POP GRIDS LOOK DECENT. DID UPDATE GRIDS WITH LATEST OBS
AND TRENDS...OTHERWISE GIVEN UNCERTAINTY NO MAJOR CHANGES PLANNED
THIS UPDATE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 405 PM EDT MON APR 6 2015
THE REGION WAS IN A SOMEWHAT ZONAL PATTERN WITH WEST TO WEST
SOUTHWESTERLY FLOW ALOFT BETWEEN A TROUGH OVER EASTERN CANADA AND
THE NORTHERN GREAT LAKES AND A RIDGE CENTERED OVER THE GULF OF
MEXICO. FURTHER WEST...A TROUGH WAS GRADUALLY WORKING ONSHORE OF
THE WEST COAST OF THE CONUS. A SHORTWAVE TROUGH WORKING FROM THE
NORTHERN GREAT LAKES INTO THE NORTHEASTERN CONUS WILL PUSH A COLD
FRONT SOUTH FROM THE GREAT LAKES REGION DOWN TO NEAR THE I 70
CORRIDOR OR SLIGHT SOUTH OF THAT...BUT REMAIN NORTH OF THE OH
RIVER. THEN...AS THE TROUGH WORKS FURTHER INTO THE WESTERN
CONUS...THIS BOUNDARY WILL RETREAT NORTH LATE IN THE SHORT TERM
PERIOD WITH AND AN OLD BOUNDARY CURRENTLY EXTENDING FROM THE
CENTRAL PLAINS INTO THE DEEP SOUTH ALSO BECOMING MORE ILL DEFINED
AND RETREATING NORTH...POSSIBLY NORTH OF THE OH RIVER LATE. THIS
WILL OCCUR AS HEIGHTS RISE ACROSS THE SOUTHEASTERN CONUS.
AN AREA OF SHOWERS AND VERY FEW EMBEDDED THUNDERSTORMS AT PRESENT
IS APPROACHING OF EASTERN KENTUCKY FROM CENTRAL AND WESTERN KY AND
MIDDLE TN ASSOCIATED WITH ISENTROPIC LIFT OVER THE BOUNDARY TO OUR
SOUTHWEST AND WEST. RAINFALL OF NEARLY A HALF OF AN INCH HAS
OCCURRED AT KBNA. THE GENERAL MODEL CONSENSUS IS FOR THIS ACTIVITY
TO BE MOST WIDESPREAD ACROSS THE SOUTHERN CWA DURING THIS
EVENING...ALTHOUGH ISOLATED TO SCATTERED ACTIVITY IS POSSIBLE
ACROSS THE NORTH. NOT MUCH IN THE WAY OF THUNDER IS EXPECTED WITH
THIS AS THE ATMOSPHERE CONTINUES TO MOISTEN. HOWEVER...SOME
LOCALLY HIGHER RAINFALL IS POSSIBLE IN ANY HEAVIER SHOWERS OR ANY
THUNDERSTORMS.
AFTER THAT...MCS ACTIVITY SHOULD BEGIN TO DEVELOP SOUTH OF THE
FRONT TO OUR NORTH AND POSSIBLY NEARER TO THE BOUNDARY TO THE
SOUTHWEST OF THE AREA. CONFIDENCE IN THE DETAILS AND EVOLUTION OF
THIS IS NOT HIGH...WITH DIFFERENCES FROM MODEL RUN TO MODEL RUN.
HOWEVER... PRECIP CHANCES APPEAR BEST THIS EVENING...WITH SOMEWHAT
OF A LULL TOWARD MIDNIGHT INTO THE OVERNIGHT HOURS. TOWARD DAWN
AND INTO TUESDAY MORNING APPEARS TO BE THE NEXT PERIOD WITH THE
HIGHEST CHANCES FOR SHOWERS AND THUNDERSTORMS. THE NORTHERN PART
OF THE AREA COULD EXPERIENCE THE MORE PERSISTENT ACTIVITY OR AT
LEAST QPF FROM THIS AS THEY WILL BE CLOSER TO THE BOUNDARY. THE
MODEL CONSENSUS IS FOR A SHORTWAVE TROUGH TO MOVE THROUGH THE
REGION TOMORROW AFTERNOON INTO TOMORROW EVENING...WITH HEIGHTS
THEN RISING ACROSS THE SOUTHEASTERN CONUS. WITH THE LOSS OF
DAYTIME HEATING AND THE BOUNDARY RETREATING NORTH...CHANCES FOR
SHOWERS AND THUNDERSTORMS APPEAR AS IF THEY WOULD DECREASE FOR A
WHILE FROM MID TO LATE EVENING INTO THE OVERNIGHT HOURS.
HOWEVER... ADDITIONAL WEAK WAVES IN THE FLOW MAY LEAD TO NOCTURNAL
DEVELOPMENT IN THE WARM AND MOIST AIRMASS IN PLACE ACROSS THE OH
VALLEY AND MS VALLEY REGION LATE IN THE PERIOD.
WITH A MUCH MORE MOIST AIRMASS IN PLACE AND RATHER PERSISTENT
CLOUD COVER EXPECTED FOR MUCH OF THE PERIOD...DIURNAL RANGES WILL
BE MORE LIMITED THAN RECENT DAYS. PARTIAL CLEARING COULD BRING
SMALL RIDGE/VALLEY SPLITS TONIGHT AND OR TUESDAY NIGHT IF AND
WHERE IT OCCURS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 405 PM EDT MON APR 6 2015
THE EXTENDED PERIOD LOOKS TO BE QUITE ACTIVE WITH MULTIPLE
IMPULSES RIDING OVER A BROAD RIDGE SET UP ACROSS THE EASTERN
CONUS...AND A WARM FRONT STALLED OUT NORTH OF THE REGION.
THE IMPULSES MOVING OVER THE RIDGE AND ALONG THE BOUNDARY
WILL BRING RAIN AND THUNDERSTORM CHANCES THROUGH THE END OF
THE WORK WEEK. THE RISK OF ORGANIZED AND MORE THREATENING
STORMS DEVELOPS LATER THURSDAY AND CONTINUES THROUGH FRIDAY
DUE TO THE APPROACHING SFC LOW AND TROF. THE SFC LOW THEN
LIFTS TOWARDS THE GREAT LAKES REGION ON FRIDAY WITH A SLOW
MOVING COLD FRONT PASSING THROUGH THE AREA FRIDAY EVENING.
THERE ARE SOME DIFFERENCES BETWEEN THE MODELS ON THE TIMING
OF THE FRONTAL PASSAGE SO HAVE WENT WITH A COMPROMISE BETWEEN
GFS/ECMWF. ADDITIONALLY... THERE WILL BE AMPLE MOISTURE FOR
THE STORMS TO TAP INTO...WITH PW VALUES EXCEEDING 1.25" OR ABOVE 2
STANDARD DEVIATIONS ABOVE NORMAL. THEREFORE...MODERATE TO HEAVY
RAINFALL WILL BE A THREAT FOR THE END OF THE WEEK.
DRIER WEATHER RETURNS FOR THE WEEKEND AS A SFC RIDGE BUILDS IN
OVER THE OHIO VALLEY. THIS WILL ALSO BRING MORE SEASONABLE
TEMPERATURES TO THE STATE FOLLOWING A WEEK OF WELL ABOVE NORMAL
TEMPERATURES....WHERE SOME LOW 80S COULD BE SEEN...DESPITE THE
CLOUDINESS AND PERIODS OF RAIN. THE BEGINNING OF NEXT WEEK BRINGS
MORE CHANCES FOR RAIN AS ANOTHER TROF AND SURFACE LOW MOVES
TOWARDS OUR AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 210 AM EDT TUE APR 7 2015
THE LATEST HRRR AND NAM12 HOLD OFF ON ANY SIGNIFICANT PCPN MOVING
INTO EAST KENTUCKY UNTIL CLOSER TO 12Z. THIS LINES UP WELL WITH A
CLUSTER OF SHOWERS AND THUNDERSTORMS NOW MOVING THROUGH SOUTHERN
ILLINOIS...INDIANA AND NORTHWEST KENTUCKY. MVFR CIGS WILL BE THE
RULE FOR MOST OF THE AREA THROUGH THE TAF PERIOD AS THIS INITIAL
WAVE APPROACHES AND PASSES THROUGH THIS MORNING FOLLOWED BY
ANOTHER POSSIBLE IMPULSE LATER THIS EVENING WITH ADDITIONAL LOW
CIGS AND SHOWERS/STORMS. IN THE HEAVIER CONVECTION...MVFR VIS
WILL BE A GOOD BET WITH OCCASIONAL IFR VIS OR CIGS IN STORMS.
THROUGH THE TAF PERIOD...WINDS WILL GENERALLY BE FROM THE SOUTH AT
5 TO 10 KTS...EXCEPT IN HIGHER GUSTS IN STORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...JP
LONG TERM...JVM/GREIF
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
426 AM EDT TUE APR 7 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 421 AM EDT TUE APR 7 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR MI UNDER A
CONFLUENT WNW FLOW ALOFT BTWN ARCTIC BRANCH CLOSED LO OVER NRN
QUEBEC AND SRN BRANCH RDG IN THE PLAINS DOWNSTREAM OF TROF ALONG THE
W COAST. UPR MI REMAINS IN THE RRQ OF 130KT H3 JET MAX WITHIN THE
CONFLUENCE ZN OF THESE TWO BRANCHES. WV IMAGERY AND RUC ANALYSIS
ALSO INDICATE A SHRTWV OVER NDAKOTA THAT IS SLIDING TO THE E. THE
DPVA/MID LVL QVECTOR CNVGC AHEAD OF THIS SHRTWV AND SOME UPR
DVGC/MID LVL FGEN IN THE RRQ OF THE UPR JET ARE AIDING A LINE OF
LIGHT SN/MIXED PCPN ACRS NCENTRAL WI INTO FAR SRN MNM COUNTY WELL TO
THE N OF FAIRLY SHARP H85 WARM FNT ORIENTED W-E ACRS THE LOWER LKS.
HOWEVER...THE NNE LLVL FLOW OF VERY DRY AIR SHOWN ON THE 00Z INL
RAOB TO THE S OF HI PRES STRETCHING FM NEAR LK WINNIPEG ACROSS NW
ONTARIO AND INTO QUEBEC IS PREVENTING THIS PCPN FM MOVING FARTHER TO
THE N. BUT THERE ARE PLENTY OF MID/HI CLDS OVER THE CWA...THICKEST
OVER THE SRN TIER. LOOKING FARTHER UPSTREAM...ANOTHER SHRTWV IS
LIFTING TOWARD THE NRN PLAINS IN THE SW FLOW ALOFT BTWN THE PLAINS
RDG AND THE TROF ALONG THE W COAST.
MAIN FCST CONCERNS THRU TNGT WL BE POPS ALONG THE WI BORDER EARLY
THIS FCST PERIOD IN ASSOCIATION WITH THE SHRTWV NOW APRCH MN. FOCUS
FOR TNGT WL BE ON IMPACT OF SECOND DISTURBANCE APRCHG THE NRN PLAINS
AND ANOTHER DISTURBANCE THE MODELS SHOW WL MOVE THRU WI.
TDAY...FIRST SHRTWV OVER NW MN IS FCT TO DRIFT TO THE E AND INTO RRQ
OF UPR STREAK TO THE E...ACCOMPANIED BY AN AREA OF DEEP LYR QVECTOR
CNVGC. ALTHOUGH THIS SETUP WOULD NORMALLY SUPPORT WDSPRD PCPN...ALL
THE MODELS SHOW A STEADY FEED OF SFC-H85 DRY AIR FM THE NE THRU THE
DAY. IN FACT...AFTER LINGERING PCPN ENDS EARLY THIS MRNG OVER FAR
SRN MENOMINEE COUNTY...ALL OF THE MODELS SHOW NO PCPN OVER UPR MI
THRU 00Z THIS EVNG. BUT WITH CONSIDERABLE MID/HI CLD ABOVE THE LLVL
DRY AIR AND AN ENE WIND OFF THE CHILLY LK WATERS...MAX TEMPS THIS
AFTN SHOULD RUN BLO NORMAL. EXPECT READINGS TO REACH THE LO 40S AWAY
FM THE LKS...WHERE TEMPS WL HOLD IN THE 30S.
TNGT...AS THE CONFLUENCE ZN SHIFTS SLOWLY TO THE NE TDAY...SHRTWV
NOW TRACKING INTO THE NRN PLAINS IS FCST TO LIFT NE INTO SCENTRAL
CANADA...WITH BULK OF DEEP LYR QVECTOR CNVGC PASSING TO THE NW. BUT
GENERAL MODEL CONSENSUS ALSO HINTS ANOTHER SHRTWV EMERGING FM THE
WRN TROF AND THRU THE PLAINS TDAY WL DRIFT INTO WI LATE TNGT...
ACCOMPANIED BY AREA OF FAIRLY SHARP UPR DVGC EVEN AS THE MAIN UPR
JET CORE TO THE E SLIPS FARTHER AWAY ALONG WITH THE UPR CONFLUENCE
ZN. MOST OF THE MODELS FOCUS SOMEWHAT HIER QPF OVER THE SCNTRL
CWA...CLOSER TO WHERE THE CORE OF UPR DVGC/AXIS OF SHARPEST MID LVL
FGEN TO THE N OF H85 WARM FNT THAT IS FCST TO LIFT NWD WITH THE APRCH
OF THIS DISTURBANCE. DESPITE THE GENERAL AGREEMENT ON THESE
FEATURES...MODEL QPF AND FCST THERMAL FIELDS ARE QUITE VARIABLE. THE
GFS IS WETTEST OVERALL...SHOWING AS MUCH AS 0.25-0.35 INCH OVER THE
SCNTRL CLOSER TO THE SHARPER FORCING/FGEN AND WHERE THIS MODEL SHOWS
H7 SPECIFIC HUMIDITY IN THE 3-4 G/KG RANGE. BUT MANY OF THE HIER RES
MODELS...LIKE THE 00Z NAM AND REGIONAL CNDN...SHOW LTL IF ANY PCPN
EVEN THERE. GIVEN PERSISTENCE OF LLVL DRY AIR OVER THE NE CWA AND THE
WEAKENING OF THE FORCING WITH TIME AS THE DISTURBANCE LIFTS TO THE
NE...WL TEND TO KEEP THE NE CWA DRIER LONGER. PTYPE WL BE A
CONCERN...AND MODEL DIFFERENCES COMPOUND THE UNCERTAINTY. SINCE THE
GFS SHOWS MORE VERTICAL MOTION/QPF AND THUS MORE DYNAMIC/EVAPORATIVE
COOLING...THAT MODEL FCST SDNGS INDICATE A MAINLY SN EVENT...WITH SN
AMOUNTS OVER THE SCENTRAL AT LEAST APRCHG ADVY CRITERIA. CONSIDERING
THE WIDE DIFFERENCES IN QPF/IMPACT OF LINGERING DRY AIR...DID NOT
CONSIDER AN ADVY ATTM EVEN THOUGH TRACK OF DISTURBANCE TO THE S AND
VERY DRY NATURE OF THE ANTECEDENT AIRMASS WOULD FAVOR MAINLY SN. MANY
OF THE OTHER MODELS SHOW AN ELEVATED WARM LYR WITH MAX TEMPS ALOFT
OVER 0C. WITH LLVL DRY AIR THAT WL ALLOW FOR MORE NEAR SFC
COOLING...FREEZING RA AND PERHAPS SLEET...ESPECIALLY NEAR THE ONSET
OF THE PCPN WHEN THE LLVLS ARE DRIER AND WBLB TEMPS LO ENUF TO ALLOW
FOR A BETTER CHC FOR THE DROPS TO FREEZE INTO ICE PELLETS...ARE
POSSIBLE. SO RETAINED A MENTION OF THESE PTYPES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 359 AM EDT TUE APR 7 2015
THE SECOND HALF OF THE WORK WEEK CONTINUES TO LOOK ACTIVE WITH
PERIODS OF MIXED PRECIPITATION...BEFORE TRENDING DRIER WITH NORMAL
TO ABOVE NORMAL TEMPERATURES THIS WEEKEND. ANOTHER UPPER TROUGH
WILL AFFECT THE REGION FOR THE START OF NEXT WEEK...BUT AT THIS
POINT...THERMAL PROFILES SUPPORT RAIN FOR THE PRECIP TYPE.
TO START THE LONG TERM PERIOD...THE SHORTWAVE THAT WILL BE
PRODUCING PRECIPITATION OVER PARTS OF THE UPPER GREAT LAKES REGION
WILL BE QUICKLY SHIFTING EAST OUT OF THE THE AREA WEDNESDAY MORNING.
THIS MAY LEAD TO SOME LINGERING SHOWERS TO DURING THE MORNING AND
WITH THE DEEP MOISTURE DEPARTING IT WILL LEAD TO A WINTRY MIX IF
PRECIPITATION OCCURS. WHILE THE LARGE SCALE SUPPORT DEPARTS AT THE
START OF THE PERIOD...THE HIGH PRESSURE RIDGE WILL ALSO QUICKLY
LEAVE THE REGION AND ALLOW FOR PLENTY OF CLOUDS TO REMAIN OVER THE
U.P. FOR WEDNESDAY. THE LATEST TRENDS IN THE MODELS IS FOR LOW LEVEL
MOISTURE TO REMAIN OVER THE AREA...AND WITH SOUTHEASTERLY 950-925MB
FLOW DEVELOPING THROUGH THE DAY...EXPECT THERE TO BE SOME UPSLOPE
DRIZZLE FOR THE HIGHER TERRAIN OF CENTRAL UPPER MICHIGAN. THE
GFS CONTINUES TO HIGHLIGHT EVEN MEASURABLE DRIZZLE BUT WITH MUCH OF
THE OTHER MODELS SHOWING DRY NEAR SURFACE AIR...WILL ONLY SHOW
SLIGHT CHANCE POPS FOR THE DRIZZLE.
ATTENTION THEN TURNS TO THE UPPER TROUGH LIFTING NORTHEAST OUT OF
THE CENTRAL PLAINS WEDNESDAY NIGHT AND PHASING WITH A WAVE MOVING
THROUGH CANADA THURSDAY AFTERNOON INTO THURSDAY NIGHT AS IT MOVES
THROUGH THE UPPER GREAT LAKES REGION. THERE CONTINUES TO BE TWO
WAVES OF PRECIPITATION EXPECTED WITH THIS SYSTEM. THE FIRST WILL BE
TIED TO THE STRONG WARM AIR ADVECTION AND LEADING SHORTWAVE LIFTING
NORTHEAST THROUGH THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY
MORNING. MODEL CONSENSUS HAS THE BEST SHORTWAVE ENERGY MISSING THE
U.P. TO THE SOUTHEAST BUT THEY DIFFER ON WHERE THE FOCUS OF THE BEST
WARM AIR ADVECTION WILL BE OVER THE U.P. THUS...CONFIDENCE REMAINS
LOW ON THE TRACK OF THE HEAVIEST PRECIPITATION (0.15-0.3IN OF
LIQUID...HIGHEST OVER THE SOUTH CENTRAL). AS FOR PRECIP TYPE...WITH
900-800MB TEMPERATURES WELL ABOVE FREEZING WITHIN THAT BEST
FORCING...WOULD EXPECT THE PRECIPITATION TO FALL AS RAIN. WHICH
LEAVES THE SURFACE TEMPERATURES TO DETERMINE WHETHER IT IS FREEZING
RAIN OR NOT. ONE POSITIVE WITH THE WARMER WEATHER OVER THE LAST
COUPLE OF WEEKS IS THAT IT HAS HELPED WARM THE SURFACE TEMPERATURES
ACROSS THE AREA. TODAY...EVEN WITH THE COOLER TEMPERATURES...ROAD
SURFACE TEMPERATURES WERE IN THE MID-UPPER 30S. THUS...WITH THE
CLOUDS ON WEDNESDAY INTO WEDNESDAY NIGHT HELPING TO INSULATE AND
KEEP LOWS AROUND 30 DEGREES (TRENDED THEM UP A COUPLE DEGREES)...THE
IMPACT OF THE FREEZING RAIN MAY BE A LITTLE LESS (ESPECIALLY IF
ROADS ARE TREATED IN ADVANCE). WILL CONTINUE TO ADDRESS THIS
FREEZING RAIN THREAT IN THE HWO.
AFTER A BRIEF LULL IN THE STRONGER PRECIPITATION ON THURSDAY
AFTERNOON...THE UPPER TROUGH WILL LIFT NORTHEAST THROUGH THE UPPER
GREAT LAKES REGION THURSDAY NIGHT INTO FRIDAY MORNING WHILE THE
SURFACE LOW TRACKS FROM CENTRAL IOWA AT 18Z THURSDAY TO NORTHERN
LAKE HURON AT 18Z ON FRIDAY. VERY CONFIDENT ON PRECIPITATION
OCCURRING DURING THAT PERIOD...BUT CONFIDENCE IS LACKING ON THE
AMOUNTS/LOCATION DUE TO DIFFERENCES WITH THE TRACK/INTENSITY OF THE
LOW AND THE MID LEVEL FGEN BAND. THIS IS ALL TIED TO THE PHASING OF
THE TWO WAVES...WHICH IS NOTORIOUSLY DIFFICULT FOR MODELS TO PIN
DOWN AT THIS STAGE. THUS...WILL FOLLOW A GENERAL CONSENSUS OF THE
MODELS (LEANING TOWARDS GFS/ECMWF) BOTH FOR QPF AND THERMAL FIELDS
AS THAT SEEMS TO REPRESENT THE POSSIBILITIES THE BEST AT THIS TIME.
AT THIS POINT...THINK THE GEM/NAM SEEM LIKE THE OUTLIERS WITH THE
FARTHER NORTHWEST TRACK (ALONG LAKE MICHIGAN AND THE U.P. SHORELINE)
WITH THE 12Z ECMWF AND 00Z GFS ENSEMBLE MEMBERS SUPPORTING A TRACK
MORE THROUGH NORTHERN LOWER MICHIGAN. THE LATE ARRIVING 00Z ECMWF
REMAINS MUCH WEAKER THAN THE OTHER SOLUTIONS...AS IT HAS
TRENDED TOWARDS LESS PHASING AND MORE OF A GLANCING BLOW BY THE
NORTHERN STREAM WAVE. IF THAT VERIFIES...IT WOULD LEAD TO MUCH LESS
PRECIPITATION FOR THE AREA FOR THE THURSDAY NIGHT PERIOD AND DRY BY
FRIDAY AFTERNOON. EXPECT THE PRECIP TO START AS RAIN INITIALLY AND
THEN GRADUALLY TRANSITION TO OR MIX WITH SNOW FROM WEST TO EAST.
WITH ALL OF THE UNCERTAINTY...DON/T WANT TO GET TOO HUNG UP IN
SNOWFALL AMOUNTS...BUT THERE COULD BE SLUSHY ACCUMULATIONS WEST OF
A LINE FROM MARQUETTE TO CRYSTAL FALLS. THIS SECOND WAVE OF PRECIP
IS STILL AN EVOLVING SITUATION THAT WILL NEED TO BE FINE TUNED OVER
THE NEXT SEVERAL SHIFTS.
THE UPPER TROUGH AND SURFACE LOW WILL QUICKLY DEPART FRIDAY NIGHT
AND BRING A QUICK DRYING TREND TO THE AREA AS A SURFACE RIDGE MOVES
EAST OVER THE AREA BY SATURDAY MORNING. WITH LIMITED COLD AIR
BEHIND THIS SYSTEM AND AN UPPER RIDGE MOVING INTO THE UPPER GREAT
LAKES REGION...SHOULD SEE NEAR NORMAL TEMPERATURES ON SATURDAY WITH
MOSTLY SUNNY SKIES. THAT UPPER/SURFACE RIDGE WILL SHIFT EAST ON
SATURDAY NIGHT...LEADING TO SOUTHWESTERLY WINDS BRINGING WARMER AIR
TO THE AREA FOR SUNDAY AND HAVE HIGHS RISING INTO THE UPPER 50S
OVER THE WEST AND AROUND 50 OVER THE EAST. THAT SOUTHWESTERLY FLOW
WILL BE OUT AHEAD OF THE NEXT UPPER TROUGH THAT WILL BE MOVING
ACROSS THE CANADIAN ROCKIES THIS WEEKEND AND IMPACTING THE AREA
SUNDAY NIGHT INTO THE FIRST PART OF NEXT WEEK. AT THIS POINT...THE
THERMAL PROFILES WOULD SUPPORT RAIN FOR MONDAY AND WILL SHOW
INCREASING POPS SUNDAY NIGHT AND CONTINUE CHANCE POPS INTO MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 120 AM EDT TUE APR 7 2015
HIGH PRES RIDGE EXTENDING ACROSS NRN ONTARIO WILL ADVECT LOW-LEVEL
DRY AIR S AND W ACROSS UPPER MI THROUGH THIS EVNG. AS A RESULT...VFR
CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW DURING THIS TIME DESPITE
CONSIDERABLE MID/HI CLDS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 421 AM EDT TUE APR 7 2015
WITH LAKE SUPERIOR SITUATED BETWEEN HI PRES THAT WILL MOVE ACROSS NW
ONTARIO INTO QUEBEC THRU WED AND A WARM FRONT THAT WILL REMAIN TO
THE S AND SW ACROSS THE PLAINS TO OHIO VALLEY...E TO NE WINDS WILL
PERSIST. TYPICAL FOR E TO NE WINDS...WINDS WILL BE STRONGEST OVER
WRN LAKE SUPERIOR...IN PARTICULAR BTWN THE APOSTLE ISLANDS AND MN
NSHORE WHERE FUNNELING/COASTAL CONVERGENCE ENHANCE THE WINDS. IN
THAT AREA...15-25KT WINDS WILL INCREASE TO 20-30KT THIS MORNING INTO
THIS EVENING. E TO NE WINDS...MOSTLY 10-20KT...WILL THEN CONTINUE ON
WED AND ON INTO THU AS LO PRES LIFTS NE FROM THE CENTRAL PLAINS
TOWARD THE GREAT LAKES REGION. AT THIS TIME...NO GALES APPEAR
LIKELY. BUT WINDS WILL BACK TO THE N AND THEN NW UP TO 25 KTS THU
NIGHT INTO FRI ONCE THE LO SHIFTS TO THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
401 AM EDT TUE APR 7 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 429 PM EDT MON APR 6 2015(TODAY AND TONIGHT)
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW CONFLUENT WESTERLY FLOW
ACROSS THE UPPER LAKES BTWN NRN BRANCH TROF OVER ERN CANADA AND SRN
BRANCH RIDGE OVER THE CNTRL CONUS WHICH IS DOWNSTREAM OF A STRONG
TROF ALONG/JUST OFF THE W COAST. SNOW THAT AFFECTED MUCH OF SRN
UPPER MI LAST NIGHT/EARLIER TODAY HAS LARGELY ENDED AS SUBTLE
SHORTWAVE/STRONGER RIGHT ENTRANCE FORCING FROM UPPER JET ALONG AND
LOW/MID LEVEL FRONTOGENESIS HAVE SHIFTED E. TO THE N...A DRY AIR
MASS ASSOCIATED WITH SFC HIGH PRES RIDGING FROM
SASKATCHEWAN/MANITOBA INTO NRN ONTARIO/NRN LAKE SUPERIOR CONTINUES
TO FEED TO THE S AND W.
RIGHT ENTRANCE OF THE UPPER JET WITHIN THE CONFLUENCE ZONE REMAINS
OVER THE UPPER MISSISSIPPI VALLEY/UPPER LAKES REGION TONIGHT. THERE
ARE SOME HINTS THAT ANOTHER SUBTLE SHORTWAVE AND RIBBON OF
FRONTOGENESIS WILL STREAK ACROSS FAR SCNTRL UPPER MI THIS EVENING.
THIS MAY LEAD TO ANOTHER BAND OF SNOW STREAKING ACROSS MAINLY
MENOMINEE COUNTY. LATEST RAP/HRRR SUPPORT THIS IDEA AS DO THE 12Z
NAM AND HIRES WRF-ARW/NMM TO VARYING DEGREES. RADAR TRENDS UPSTREAM
LEND SOME SUPPORT AS WELL. WILL SHOW AN UPTICK IN POPS ACROSS THE
SRN HALF OF MENOMINEE COUNTY THIS EVENING WITH SNOW ACCUMULATIONS
PROBABLY LESS THAN 1 INCH. EXPECT A SHARP CUTOFF TO THE SNOW FARTHER
N AS DRIER AIR FROM THE HIGH PRES RIDGE TO THE N AND NE CONTINUES TO
ADVECT S AND W. WILL CARRY SCHC POPS AS FAR N AS US-2 FROM IRON
RIVER TO ESCANABA. SNOW WILL END OVERNIGHT. EXPECT MIN TEMPS IN THE
20S ACROSS THE AREA...THOUGH SOME TEENS ARE POSSIBLE IN THE USUAL
COLDER SPOTS ACROSS THE N AND E AS CLOUDS MAY THIN ENOUGH TO AID
COOLING OVERNIGHT.
QUIET DAY EXPECTED ON TUE AS ALL MODEL GUIDANCE IS IN GOOD AGREEMENT
ON DRY AIR DOMINATING IN THE LOWER LEVELS. FAVORED THE LOWER SIDE OF
GUIDANCE FOR TEMPS WITH THE IDEA THAT FAIRLY THICK HIGHER CLOUDS
WILL PREVENT SIGNIFICANT WARMING. E TO NE WIND ALSO ARGUES FOR THE
COOLER SIDE OF GUIDANCE...ESPECIALLY SO FROM THE KEWEENAW ACROSS THE
NCNTRL AND S OF KESC NEAR LAKE MI. LOW TO MID 30S SHOULD BE THE RULE
IN THOSE AREAS. ELSEWHERE...TEMPS SHOULD RISE TO AROUND 40F...
HIGHEST WHERE E TO NE WINDS DOWNSLOPE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 359 AM EDT TUE APR 7 2015
THE SECOND HALF OF THE WORK WEEK CONTINUES TO LOOK ACTIVE WITH
PERIODS OF MIXED PRECIPITATION...BEFORE TRENDING DRIER WITH NORMAL
TO ABOVE NORMAL TEMPERATURES THIS WEEKEND. ANOTHER UPPER TROUGH
WILL AFFECT THE REGION FOR THE START OF NEXT WEEK...BUT AT THIS
POINT...THERMAL PROFILES SUPPORT RAIN FOR THE PRECIP TYPE.
TO START THE LONG TERM PERIOD...THE SHORTWAVE THAT WILL BE
PRODUCING PRECIPITATION OVER PARTS OF THE UPPER GREAT LAKES REGION
WILL BE QUICKLY SHIFTING EAST OUT OF THE THE AREA WEDNESDAY MORNING.
THIS MAY LEAD TO SOME LINGERING SHOWERS TO DURING THE MORNING AND
WITH THE DEEP MOISTURE DEPARTING IT WILL LEAD TO A WINTRY MIX IF
PRECIPITATION OCCURS. WHILE THE LARGE SCALE SUPPORT DEPARTS AT THE
START OF THE PERIOD...THE HIGH PRESSURE RIDGE WILL ALSO QUICKLY
LEAVE THE REGION AND ALLOW FOR PLENTY OF CLOUDS TO REMAIN OVER THE
U.P. FOR WEDNESDAY. THE LATEST TRENDS IN THE MODELS IS FOR LOW LEVEL
MOISTURE TO REMAIN OVER THE AREA...AND WITH SOUTHEASTERLY 950-925MB
FLOW DEVELOPING THROUGH THE DAY...EXPECT THERE TO BE SOME UPSLOPE
DRIZZLE FOR THE HIGHER TERRAIN OF CENTRAL UPPER MICHIGAN. THE
GFS CONTINUES TO HIGHLIGHT EVEN MEASURABLE DRIZZLE BUT WITH MUCH OF
THE OTHER MODELS SHOWING DRY NEAR SURFACE AIR...WILL ONLY SHOW
SLIGHT CHANCE POPS FOR THE DRIZZLE.
ATTENTION THEN TURNS TO THE UPPER TROUGH LIFTING NORTHEAST OUT OF
THE CENTRAL PLAINS WEDNESDAY NIGHT AND PHASING WITH A WAVE MOVING
THROUGH CANADA THURSDAY AFTERNOON INTO THURSDAY NIGHT AS IT MOVES
THROUGH THE UPPER GREAT LAKES REGION. THERE CONTINUES TO BE TWO
WAVES OF PRECIPITATION EXPECTED WITH THIS SYSTEM. THE FIRST WILL BE
TIED TO THE STRONG WARM AIR ADVECTION AND LEADING SHORTWAVE LIFTING
NORTHEAST THROUGH THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY
MORNING. MODEL CONSENSUS HAS THE BEST SHORTWAVE ENERGY MISSING THE
U.P. TO THE SOUTHEAST BUT THEY DIFFER ON WHERE THE FOCUS OF THE BEST
WARM AIR ADVECTION WILL BE OVER THE U.P. THUS...CONFIDENCE REMAINS
LOW ON THE TRACK OF THE HEAVIEST PRECIPITATION (0.15-0.3IN OF
LIQUID...HIGHEST OVER THE SOUTH CENTRAL). AS FOR PRECIP TYPE...WITH
900-800MB TEMPERATURES WELL ABOVE FREEZING WITHIN THAT BEST
FORCING...WOULD EXPECT THE PRECIPITATION TO FALL AS RAIN. WHICH
LEAVES THE SURFACE TEMPERATURES TO DETERMINE WHETHER IT IS FREEZING
RAIN OR NOT. ONE POSITIVE WITH THE WARMER WEATHER OVER THE LAST
COUPLE OF WEEKS IS THAT IT HAS HELPED WARM THE SURFACE TEMPERATURES
ACROSS THE AREA. TODAY...EVEN WITH THE COOLER TEMPERATURES...ROAD
SURFACE TEMPERATURES WERE IN THE MID-UPPER 30S. THUS...WITH THE
CLOUDS ON WEDNESDAY INTO WEDNESDAY NIGHT HELPING TO INSULATE AND
KEEP LOWS AROUND 30 DEGREES (TRENDED THEM UP A COUPLE DEGREES)...THE
IMPACT OF THE FREEZING RAIN MAY BE A LITTLE LESS (ESPECIALLY IF
ROADS ARE TREATED IN ADVANCE). WILL CONTINUE TO ADDRESS THIS
FREEZING RAIN THREAT IN THE HWO.
AFTER A BRIEF LULL IN THE STRONGER PRECIPITATION ON THURSDAY
AFTERNOON...THE UPPER TROUGH WILL LIFT NORTHEAST THROUGH THE UPPER
GREAT LAKES REGION THURSDAY NIGHT INTO FRIDAY MORNING WHILE THE
SURFACE LOW TRACKS FROM CENTRAL IOWA AT 18Z THURSDAY TO NORTHERN
LAKE HURON AT 18Z ON FRIDAY. VERY CONFIDENT ON PRECIPITATION
OCCURRING DURING THAT PERIOD...BUT CONFIDENCE IS LACKING ON THE
AMOUNTS/LOCATION DUE TO DIFFERENCES WITH THE TRACK/INTENSITY OF THE
LOW AND THE MID LEVEL FGEN BAND. THIS IS ALL TIED TO THE PHASING OF
THE TWO WAVES...WHICH IS NOTORIOUSLY DIFFICULT FOR MODELS TO PIN
DOWN AT THIS STAGE. THUS...WILL FOLLOW A GENERAL CONSENSUS OF THE
MODELS (LEANING TOWARDS GFS/ECMWF) BOTH FOR QPF AND THERMAL FIELDS
AS THAT SEEMS TO REPRESENT THE POSSIBILITIES THE BEST AT THIS TIME.
AT THIS POINT...THINK THE GEM/NAM SEEM LIKE THE OUTLIERS WITH THE
FARTHER NORTHWEST TRACK (ALONG LAKE MICHIGAN AND THE U.P. SHORELINE)
WITH THE 12Z ECMWF AND 00Z GFS ENSEMBLE MEMBERS SUPPORTING A TRACK
MORE THROUGH NORTHERN LOWER MICHIGAN. THE LATE ARRIVING 00Z ECMWF
REMAINS MUCH WEAKER THAN THE OTHER SOLUTIONS...AS IT HAS
TRENDED TOWARDS LESS PHASING AND MORE OF A GLANCING BLOW BY THE
NORTHERN STREAM WAVE. IF THAT VERIFIES...IT WOULD LEAD TO MUCH LESS
PRECIPITATION FOR THE AREA FOR THE THURSDAY NIGHT PERIOD AND DRY BY
FRIDAY AFTERNOON. EXPECT THE PRECIP TO START AS RAIN INITIALLY AND
THEN GRADUALLY TRANSITION TO OR MIX WITH SNOW FROM WEST TO EAST.
WITH ALL OF THE UNCERTAINTY...DON/T WANT TO GET TOO HUNG UP IN
SNOWFALL AMOUNTS...BUT THERE COULD BE SLUSHY ACCUMULATIONS WEST OF
A LINE FROM MARQUETTE TO CRYSTAL FALLS. THIS SECOND WAVE OF PRECIP
IS STILL AN EVOLVING SITUATION THAT WILL NEED TO BE FINE TUNED OVER
THE NEXT SEVERAL SHIFTS.
THE UPPER TROUGH AND SURFACE LOW WILL QUICKLY DEPART FRIDAY NIGHT
AND BRING A QUICK DRYING TREND TO THE AREA AS A SURFACE RIDGE MOVES
EAST OVER THE AREA BY SATURDAY MORNING. WITH LIMITED COLD AIR
BEHIND THIS SYSTEM AND AN UPPER RIDGE MOVING INTO THE UPPER GREAT
LAKES REGION...SHOULD SEE NEAR NORMAL TEMPERATURES ON SATURDAY WITH
MOSTLY SUNNY SKIES. THAT UPPER/SURFACE RIDGE WILL SHIFT EAST ON
SATURDAY NIGHT...LEADING TO SOUTHWESTERLY WINDS BRINGING WARMER AIR
TO THE AREA FOR SUNDAY AND HAVE HIGHS RISING INTO THE UPPER 50S
OVER THE WEST AND AROUND 50 OVER THE EAST. THAT SOUTHWESTERLY FLOW
WILL BE OUT AHEAD OF THE NEXT UPPER TROUGH THAT WILL BE MOVING
ACROSS THE CANADIAN ROCKIES THIS WEEKEND AND IMPACTING THE AREA
SUNDAY NIGHT INTO THE FIRST PART OF NEXT WEEK. AT THIS POINT...THE
THERMAL PROFILES WOULD SUPPORT RAIN FOR MONDAY AND WILL SHOW
INCREASING POPS SUNDAY NIGHT AND CONTINUE CHANCE POPS INTO MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 120 AM EDT TUE APR 7 2015
HIGH PRES RIDGE EXTENDING ACROSS NRN ONTARIO WILL ADVECT LOW-LEVEL
DRY AIR S AND W ACROSS UPPER MI THROUGH THIS EVNG. AS A RESULT...VFR
CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW DURING THIS TIME DESPITE
CONSIDERABLE MID/HI CLDS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 429 PM EDT MON APR 6 2015
WITH LAKE SUPERIOR SITUATED BETWEEN HIGH PRES THAT WILL MOVE ACROSS
NRN ONTARIO INTO QUEBEC THRU WED MORNING AND A WARM FRONT THAT WILL
REMAIN TO THE S AND SW ACROSS THE PLAINS TO OHIO VALLEY...E TO NE
WINDS WILL PERSIST. TYPICAL FOR E TO NE WINDS...WINDS WILL BE
STRONGEST OVER WRN LAKE SUPERIOR...IN PARTICULAR BTWN THE APOSTLE
ISLANDS AND MN NSHORE WHERE FUNNELING/COASTAL CONVERGENCE ENHANCE
THE WINDS. IN THAT AREA...15-25KT WINDS WILL INCREASE TO 20-30KT
LATER TONIGHT AND CONTINUE THRU TUE NIGHT. EXPECT SOME GALE FORCE
GUSTS TUE AFTN/EVENING. E TO NE WINDS...MOSTLY 15-25KT...WILL THEN
CONTINUE THRU WED AND ON INTO THU AS LOW PRESSURE LIFTS NE FROM THE
CENTRAL PLAINS TO THE GREAT LAKES REGION. AT THIS TIME...IT DOES NOT
APPEAR THAT THE LOW WILL BE STRONG ENOUGH TO RESULT IN GALES AS IT
APPROACHES AND THEN DEPARTS. WINDS WILL BACK AROUND TO THE N AND NW
THU NIGHT AND FRI AS THE LOW EXITS TO THE NE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
121 AM EDT TUE APR 7 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 429 PM EDT MON APR 6 2015(TODAY AND TONIGHT)
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW CONFLUENT WESTERLY FLOW
ACROSS THE UPPER LAKES BTWN NRN BRANCH TROF OVER ERN CANADA AND SRN
BRANCH RIDGE OVER THE CNTRL CONUS WHICH IS DOWNSTREAM OF A STRONG
TROF ALONG/JUST OFF THE W COAST. SNOW THAT AFFECTED MUCH OF SRN
UPPER MI LAST NIGHT/EARLIER TODAY HAS LARGELY ENDED AS SUBTLE
SHORTWAVE/STRONGER RIGHT ENTRANCE FORCING FROM UPPER JET ALONG AND
LOW/MID LEVEL FRONTOGENESIS HAVE SHIFTED E. TO THE N...A DRY AIR
MASS ASSOCIATED WITH SFC HIGH PRES RIDGING FROM
SASKATCHEWAN/MANITOBA INTO NRN ONTARIO/NRN LAKE SUPERIOR CONTINUES
TO FEED TO THE S AND W.
RIGHT ENTRANCE OF THE UPPER JET WITHIN THE CONFLUENCE ZONE REMAINS
OVER THE UPPER MISSISSIPPI VALLEY/UPPER LAKES REGION TONIGHT. THERE
ARE SOME HINTS THAT ANOTHER SUBTLE SHORTWAVE AND RIBBON OF
FRONTOGENESIS WILL STREAK ACROSS FAR SCNTRL UPPER MI THIS EVENING.
THIS MAY LEAD TO ANOTHER BAND OF SNOW STREAKING ACROSS MAINLY
MENOMINEE COUNTY. LATEST RAP/HRRR SUPPORT THIS IDEA AS DO THE 12Z
NAM AND HIRES WRF-ARW/NMM TO VARYING DEGREES. RADAR TRENDS UPSTREAM
LEND SOME SUPPORT AS WELL. WILL SHOW AN UPTICK IN POPS ACROSS THE
SRN HALF OF MENOMINEE COUNTY THIS EVENING WITH SNOW ACCUMULATIONS
PROBABLY LESS THAN 1 INCH. EXPECT A SHARP CUTOFF TO THE SNOW FARTHER
N AS DRIER AIR FROM THE HIGH PRES RIDGE TO THE N AND NE CONTINUES TO
ADVECT S AND W. WILL CARRY SCHC POPS AS FAR N AS US-2 FROM IRON
RIVER TO ESCANABA. SNOW WILL END OVERNIGHT. EXPECT MIN TEMPS IN THE
20S ACROSS THE AREA...THOUGH SOME TEENS ARE POSSIBLE IN THE USUAL
COLDER SPOTS ACROSS THE N AND E AS CLOUDS MAY THIN ENOUGH TO AID
COOLING OVERNIGHT.
QUIET DAY EXPECTED ON TUE AS ALL MODEL GUIDANCE IS IN GOOD AGREEMENT
ON DRY AIR DOMINATING IN THE LOWER LEVELS. FAVORED THE LOWER SIDE OF
GUIDANCE FOR TEMPS WITH THE IDEA THAT FAIRLY THICK HIGHER CLOUDS
WILL PREVENT SIGNIFICANT WARMING. E TO NE WIND ALSO ARGUES FOR THE
COOLER SIDE OF GUIDANCE...ESPECIALLY SO FROM THE KEWEENAW ACROSS THE
NCNTRL AND S OF KESC NEAR LAKE MI. LOW TO MID 30S SHOULD BE THE RULE
IN THOSE AREAS. ELSEWHERE...TEMPS SHOULD RISE TO AROUND 40F...
HIGHEST WHERE E TO NE WINDS DOWNSLOPE.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 356 PM EDT MON APR 6 2015
THE LONG TERM FORECAST CONTINUES TO BE A CONTINUALLY FRUSTRATING
EXPERIENCE WHEN ATTEMPTING TO PIN DOWN THE FINER DETAILS OF THE
FORECAST. ESPECIALLY WITH THE UPPER GREAT LAKES REGION ON THE
NORTHERN EDGE OF THE DISTURBANCES AND HAVING THERMAL PROFILES THAT
SUPPORT MIXED PRECIPITATION AND FREEZING RAIN.
TUE NIGHT INTO WED MORNING A SHORTWAVE LOOKS TO MOVE S OF THE AREA
OR OVER THE SRN CWA. STILL LOTS OF UNCERTAINTY WITH TRACK OF THE
SHORTWAVE...LOCATION AND AMOUNT OF QPF...AND TEMPERATURE PROFILES.
THEREFORE...PRECIP AMOUNT AND TYPE ARE VERY MUCH IN QUESTION AS
WELL. IF THE COLDER GFS/ECMWF SOLUTION VERIFY...ANY PRECIP THAT
FALLS WOULD BE MORE SNOW TRANSITIONING TO FREEZING DRIZZLE AS MID
LEVEL MOISTURE CUTS OUT AND E WINDS FORCE ONSHORE/UPSLOPE PRECIP
INTO SCENTRAL UPPER MI. THE WARMER ALOFT NAM AND GEM WOULD RESULT IN
MORE FREEZING RAIN TURNING TO FREEZING DRIZZLE. THIS BEING
SAID...THE SNOW OR RAIN PORTION IS STILL QUITE UNCERTAIN. FREEZING
DRIZZLE WED MORNING SHOULD BE LIGHT AS LOW LEVEL MIXING SHOULD ALLOW
NEAR SFC LAYERS TO DRY OUT SOME.
WED AFTERNOON/EVENING LOOKS DRY INLAND...BUT COULD SEE DRIZZLE IN
UPSLOPE AREAS FROM THE E WINDS...MAINLY CENTRAL UPPER MI AND THE
KEWEENAW.
A STRONGER SHORTWAVE AND SFC LOW WILL EJECT OUT OF THE CENTRAL
PLAINS WED NIGHT...BRINGING A SURGE OF WARM AIR OVER THE CWA. MODELS
DO NOT AGREE WELL ON THE FINER DETAILS AND DO NOT HAVE GOOD RUN TO
RUN CONTINUITY. MAIN CONCERN EARLY IN THE EVENT IS WITH FREEZING
RAIN POTENTIAL WED NIGHT INTO THU MORNING. MID LEVEL TEMPS WILL
EASILY SUPPORT ALL LIQUID PRECIP...WITH SFC TEMPS DETERMINING
FREEZING RAIN POTENTIAL AS LOW LEVEL COLD AIR WILL BE TOO SHALLOW
FOR SLEET. FREEZING RAIN DOES LOOK LIKE A STRONG POSSIBILITY DURING
THIS TIME...BUT AMOUNTS OF QPF ARE STILL VERY MUCH IN QUESTION. IT
LOOKS AS THOUGH THE SYSTEM WILL PHASE WITH A NRN STREAM SYSTEM LATER
THU INTO FRI...BRINGING COLDER AIR IN FROM THE WNW LATE THU INTO
FRI. THIS FORECAST PERIOD IS EVEN MORE IN QUESTION AS MODELS
STRUGGLE WITH PHASING. IT DOES APPEAR PRECIP IS LIKELY...THE
UNCERTAINTY HAS MORE TO DO WITH PTYPE AND PRECIP AMOUNTS...FOR WHICH
SMALLER SCALE DETAILS WILL BE CRUCIAL. GIVEN THE GENERAL CONSENSUS
IDEA...THINK THAT PRECIP WILL TRANSITION FROM RAIN TO FREEZING RAIN
TO SNOW OVER WRN UPPER MI THU EVENING/NIGHT...WITH SIGNIFICANT
AMOUNTS OF EACH POSSIBLE BUT NOT CERTAIN. RAIN SHOULD TRANSITION TO
MORE OF A RAIN/SNOW MIX OVER THE CENTRAL THU NIGHT. THE ECMWF MOVES
THE PRECIP OUT OF THE AREA FRI EVENING WHILE THE GFS LINGERS PRECIP
INTO SAT MORNING. GIVEN POTENTIAL FOR FREEZING RAIN ACCUMULATION WED
NIGHT/THU MORNING AND FREEZING RAIN/SNOW POTENTIAL THU EVENING/NIGHT
WILL CONTINUE TO HIGHLIGHT IN THE HWO.
IT LOOKS LIKE SFC HIGH PRESSURE AND UPPER RIDGING SHIFT ACROSS THE
CWA OVER THE WEEKEND...WITH A WARM UP POSSIBLE AS THE HIGH SHIFTS E
AND A TROUGH MOVES TOWARD THE AREA FROM THE W. WILL JUST RUN WITH A
CONSENSU OF GUIDANCE FOR SAT-MON.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 120 AM EDT TUE APR 7 2015
HIGH PRES RIDGE EXTENDING ACROSS NRN ONTARIO WILL ADVECT LOW-LEVEL
DRY AIR S AND W ACROSS UPPER MI THROUGH THIS EVNG. AS A RESULT...VFR
CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW DURING THIS TIME DESPITE
CONSIDERABLE MID/HI CLDS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 429 PM EDT MON APR 6 2015
WITH LAKE SUPERIOR SITUATED BETWEEN HIGH PRES THAT WILL MOVE ACROSS
NRN ONTARIO INTO QUEBEC THRU WED MORNING AND A WARM FRONT THAT WILL
REMAIN TO THE S AND SW ACROSS THE PLAINS TO OHIO VALLEY...E TO NE
WINDS WILL PERSIST. TYPICAL FOR E TO NE WINDS...WINDS WILL BE
STRONGEST OVER WRN LAKE SUPERIOR...IN PARTICULAR BTWN THE APOSTLE
ISLANDS AND MN NSHORE WHERE FUNNELING/COASTAL CONVERGENCE ENHANCE
THE WINDS. IN THAT AREA...15-25KT WINDS WILL INCREASE TO 20-30KT
LATER TONIGHT AND CONTINUE THRU TUE NIGHT. EXPECT SOME GALE FORCE
GUSTS TUE AFTN/EVENING. E TO NE WINDS...MOSTLY 15-25KT...WILL THEN
CONTINUE THRU WED AND ON INTO THU AS LOW PRESSURE LIFTS NE FROM THE
CENTRAL PLAINS TO THE GREAT LAKES REGION. AT THIS TIME...IT DOES NOT
APPEAR THAT THE LOW WILL BE STRONG ENOUGH TO RESULT IN GALES AS IT
APPROACHES AND THEN DEPARTS. WINDS WILL BACK AROUND TO THE N AND NW
THU NIGHT AND FRI AS THE LOW EXITS TO THE NE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1153 PM CDT Mon Apr 6 2015
.UPDATE:
Issued at 901 PM CDT Mon Apr 6 2015
Weak, scattered convection just east of 3LF will shift east of the
forecast area later this evening, while another area of scattered,
slightly stronger convection around UUV will move eastward into
portions of southwestern IL later this evening. A persistent and
localized area of fog continues in the FAM area this evening.
Still a lot of uncertainty with regards to additional convection
for late tonight into Tuesday morning. The latest operational
models have most of their QPF across southeast MO and southwest
IL, mainly just southeast of our forecast area. Some of the high
resolution, explicit models develop more organized convection,
potentially an MCS in a region of strong low level warm air
advection on the nose of a southwesterly low level jet which moves
east-southeastward into northeast or central MO towards morning
along and just north of a developing surface warm front. This
convection should be elevated and may produce hail. The 00Z
Tuesday TOP sounding indicated a capped atmosphere which may
hinder much convective development across much of eastern KS and
western MO. For now will continue with the going forecast of pops
increasing into the chance catagory for our entire forecast area
late tonight. Unseasonably warm conditions, about 15 to 20 degrees
above normal can be expected tonight due to low level cloud
cover, south-southeasterly surface winds, low level warm air
advection, and high surface dewpoints. Temperatures in portions of
the forecast area will remain nearly steady through the night.
GKS
&&
.SHORT TERM: (Through Late Tonight)
Issued at 344 PM CDT Mon Apr 6 2015
Low pressure over the Great Plains continues to push a warm and
moist airmass into the region. Guidance suggests that convection
will blossom after 06-08Z somewhere over the CWFA as the nose of a
35-40kt low level jet runs into the 850mb baroclinic zone which is
draped over the area. Resulting isentropic lift should produce an
area of convection late tonight. This is all good in theory,
however short range guidance including the NAM and RAP show a decent
inversion above the level of free convection on forecast soundings
at various locations and times across the area. This puts
significant doubt on timing and coverage of convection late
tonight. Current feeling is that the best chance for storms to
develop will be 08Z or later, and possibly near the I-70 corridor in
Missouri. Ample pre-storm MUCAPE in excess of 1500-2000 J/kg and
persistent LLJ/isentropic lift should allow storms to increase in
coverage through 12Z. Also, with that kind of instability available
and forecast deep layer shear around 40kts, could see some storms
produce large hail. Only the uncertainty of where the storms will
form and ultimate areal coverage has dissuaded me from going with
likely or higher PoPs. As it stands, have 40-50% across the entire
CWFA late tonight, as this should allow the evening shift to
monitor latest trends and adjust as necessary.
Carney
.LONG TERM: (Tuesday through Next Monday)
Issued at 344 PM CDT Mon Apr 6 2015
Main forecast concern continues to be precipitation chances.
Obviously, threat of convection will be very high by Thursday and
Thursday night as deep upper level trof and associated surface
features push into the mid Mississippi Valley...the primary
problem is trying to pin down spatial and temporal convective
trends from tomorrow morning until the widespread and stormy
weather that is expected by Thursday.
The elevated storms that do develop late tonight should wind down
during the morning, leaving unstable but capped AMS blanketing the
area from Tuesday afternoon into Wednesday morning. Current
forecast soundings would suggest that southward sagging frontal
boundary will not be enough to bust through the warm mid level
temps, but there also seems to be some hints of very weak
shortwave energy ejecting into the area from the upper trof to our
west that could produce more elevated activity. In truth I can
probably dream up 2 or 3 scenarios on how convection could evolve
during this time, but with so much uncertainty for now plan on
sticking with going forecast trends, which generally indicate low
chance PoPs over most of the CWA during this time frame.
Fine-tuning will have to wait until this time period gets a bit
closer and specifics (hopefully) become clearer.
In spite of the considerable abiguity in precip trends heading into
mid week, today`s model guidance as well as that over the past
several days continue to point to widespread convection as we head
into Wednesday night and Thursday, with storms continuing into at
least Thursday evening. Intensifying surface low over the central
Plains on Wednesday afternoon will lead to increasing WAA
advection and isentropic ascent north of the frontal boundary.
This low level level forcing should then punch through the mid-
level cap which should begin to weaken by this time as heights
begin to fall in advance of the upper level trof. This round of
convection will work east as the synoptic front pushes north of
the area, placing the entire CWA in the warm sector of the surface
cyclone by Thursday morning. More convection should develop during
the day either from additional shortwave energy or perhaps the
effects of any residual boundaries from Wednesday night`s
activity, with a final shot of convection occurring along the cold
front as we head into the evening hours.
The synoptic models have backed off some on the instability
forecast, perhaps due to extensive cloudiness in the low levels as
well as a weakening of the nearly dry adiabtic lapse rates in the
EML that are progged early on during the forecast cycle. However,
kinematic and synoptic fields still strongly suggest a severe
weather threat...or more likely several episodes of severe
weather...from Wednesday night into Thursday evening. As alluded
to in the day3 and day 4 SPC discussions, threat of large hail and
damaging winds looks fairly substantial, while specific tornado
threat will at least be partially predicated on the specific
locations of fronts and any residual boundaries.
Uncertain how to handle the passage of the cold front/end of
thunderstorm threat. Initial thought was to slow it down a bit as a
common model bias is to be too fast with strong upper level systems,
but on the other hand convection along the front will likely be
screaming to the east, so effective bounday may race ahead of the
actual front. So, will continue thunderstorm threat across the
entire CWA on Thursday night, but will go dry by Friday.
It appears that this dry weather will continue into Saturday, with
thunderstorm chances returning by Sunday and Monday.
In spite of the fact that there will be considerable cloudiness,
there should be plenty of warmth through Thursday, with highs
primarily ranging from the middle 70s to lower 80s. The exception
to this may be over our northern counties on Wednesday, where
southward drift of the cold front will back off temps into the upper
60s and lower 70s. Arrival of the cold air will mean more
seasonable temps by Friday and Saturday.
Truett
&&
.AVIATION: (For the 06z TAFs through 06z Tuesday Night)
Issued at 1153 PM CDT Mon Apr 6 2015
Showers and thunderstorms developed in warm sector this evening
and remain just out of TAF sites. For now cigs will be the main
issue varying between VFR, MVFR and IFR. As warm front lifts north
through region, cigs to lower down to IFR between 07z and 09z
Tuesday. Models now holding off precip for TAF sites til closer to
daybreak, after 11z Tuesday, as complex develops over central MO
and slides east along I-70 corridor, before diminishing by mid
morning. Then front to lift north allowing cigs to lift and thin
out a bit. As for winds, to remain southeast to south for sites
along I-70 corridor while KUIN will see southeast winds back to
the east as front moves closer, then eventually veer back to the
south as front lifts north of KUIN.
Specifics for KSTL:
Showers and thunderstorms developed in warm sector this evening
and remain just south of metro area TAFs. For now cigs will be the
main issue varying between VFR, MVFR and IFR. As warm front lifts
north through region, cigs to lower down to IFR by 07z Tuesday.
Models now holding off precip for STL til closer to daybreak,
after 12z Tuesday, as complex develops over central MO and slides
east along I-70 corridor, before diminishing by 15z Tuesday. Then front
to lift north allowing cigs to lift and thin out a bit. As for
winds, to remain southeast to south.
Byrd
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
401 AM CDT TUE APR 7 2015
.SYNOPSIS...
ISSUED AT 400 AM CDT TUE APR 7 2015
H5 ANALYSIS FROM TONIGHT HAS A CLOSED LOW OVER NRN QUEBEC...WITH
A BROAD TROUGH EXTENDING SWD INTO NEW ENGLAND. FURTHER WEST...A
SECOND LOW WAS PRESENT OFF THE COAST OF SWRN OREGON WITH A TROUGH
EXTENDING SWD TO OFF THE COAST OF CENTRAL CALIFORNIA. AT THE
SURFACE...LOW PRESSURE WAS PRESENT OVER NORTHERN COLORADO...WITH A
STATIONARY FRONT EXTENDING ESE INTO WESTERN KS...THEN EAST
NORTHEAST INTO EAST CENTRAL KS. NORTH OF THIS FEATURE
TONIGHT...EASTERLY WINDS AND PLENTY OF LOW LEVEL MOISTURE HAVE
PUSHED INTO WESTERN AND NORTH CENTRAL NEBRASKA. IN ADDITION TO
AREAS OF FOG...OCCASIONAL DRIZZLE WAS REPORTED AT MOST OBSERVATION
STATIONS ACROSS THE FORECAST AREA OVERNIGHT TONIGHT. WITH CLOUDY
SKIES PRESENT ACROSS ALL OF WESTERN AND NORTH CENTRAL
NEBRASKA...TEMPERATURES RANGED FROM 36 AT VALENTINE TO 50 AT
BROKEN BOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT TUE APR 7 2015
OVER THE NEXT 24 HOURS...THE MAIN FORECAST CHALLENGE IS
PRECIPITATION CHANCES...ALONG WITH THE THREAT OF FOG AND DRIZZLE.
FOR THIS MORNING...LOW POPS WILL CONTINUE DUE TO A COMBINATION OF
OCCASIONAL DRIZZLE WHICH WILL BE HEAVY ENOUGH TO MEASURE...AND THE
THREAT FOR SHOWERS IN ASSOCIATION WITH A WEAK DISTURBANCE AND MID
LEVEL MOISTURE WHICH WILL CROSS THE SANDHILLS AND NORTHERN
NEBRASKA THIS MORNING. PRECIPITATION CHANCES WILL COME TO AN END
TEMPORARILY THIS AFTERNOON...AS THE BOUNDARY LAYER WARMS AND CIGS
LIFT...ALONG WITH MID LEVEL MOISTURE EXITING THE FORECAST AREA TO
THE EAST. FOR THE MOST PART...SKIES WILL REMAIN CLOUDY TODAY
ACROSS THE FORECAST AREA...AS WE REMAIN UNDER A THICK VEIL OF
STRATUS. THE EXCEPTION MAY BE ACROSS THE PANHANDLE COUNTIES...AS
THE LATEST HRRR AND NAM DO INDICATE SOME SCATTERING OUT OF CLOUDS
DURING PEAK HEATING THIS AFTERNOON. HOWEVER...THE MODELS INDICATED
A DECENT AMOUNT OF CLEARING FOR YESTERDAY WITH HEATING...WHICH FOR
THE MOST PART...DIDN/T MATERIALIZE. WITH THIS IN MIND...WENT
COOLER ON HIGHS TODAY THAN GUIDANCE...HEDGING ON CLOUDS REMAINING
ENTRENCHED ACROSS THE FORECAST AREA TODAY. CIGS WILL LOWER THIS
EVENING...WITH ANOTHER ROUND OF DRIZZLE AND FOG ACROSS THE
FORECAST AREA. FCST SOUNDINGS AND CROSS SECTIONS INDICATE A NEAR
SATURATED LAYER FROM THE SFC TO H85 TONIGHT...COLLOCATED WITH WEAK
OMEGA IN THIS LAYER AND VERY DRY CONDS ALOFT. DID GO AHEAD AND
INCREASE POPS OVERNIGHT AS SOME MID LEVEL MOISTURE LIFTS INTO THE
FORECAST AREA FROM THE SOUTHWEST...WHICH MAY LEAD TO LIGHT
PRECIPITATION IN ADDITION TO ANY DRIZZLE WHICH IS EXPECTED AS
WELL. LOWS TONIGHT WILL BE MILD GIVEN THE CLOUD COVER AND MOIST
BOUNDARY LAYER CONDS...WITH READINGS RANGING FROM THE UPPER 30S IN
THE FAR NORTH...TO LOWER TO MID 40S IN THE CENTRAL AND SOUTH.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 400 AM CDT TUE APR 7 2015
FORECAST CONCERNS CONTINUE TO DEAL WITH DRIZZLE/FOG/RAIN CHANCES
THROUGH WEDNESDAY WHICH BRING UP THE CONCERN OF TEMPERATURES. THEN
FOCUS TURNS TO MAIN UPPER LEVEL SYSTEM MOVING ACROSS THE CENTRAL
PLAINS THURSDAY WHICH BRINGS CHANCES FOR RAIN/SNOW AND STRONG WINDS
TO THE FORECAST AREA. THE PATTERN THEN REMAINS ACTIVE AS THE LOCAL
AREA GETS IMPACTED BY SYSTEMS MOVING THROUGH BOTH THE NORTHERN AND
SOUTHERN STREAMS INTO THE FIRST PART OF NEXT WEEK.
FORECAST MODELS ARE IN FAIRLY GOOD AGREEMENT THROUGH THE
PERIOD...HOWEVER THERE HAVE BEEN SOME RUN TO RUN INCONSISTENCIES
WHICH HAS KEPT CONFIDENCE LOWER THAN WOULD BE DESIRED.
BEGINNING ON WEDNESDAY...THE PRIMARY UPPER LEVEL LOW WILL MOVE INTO
THE CENTRAL ROCKIES WITH A WEAK SHORTWAVE TROUGH EJECTING OUT AHEAD
OF THE MAIN SYSTEM DURING THE DAY WEDNESDAY. MODELS CONTINUE TO
DEVELOP QPF OVER MUCH OF NEBRASKA ON WEDNESDAY...HOWEVER LOOKING AT
MOISTURE PROFILES IN CROSS SECTIONS ACROSS THE AREA AND FORECAST
SOUNDINGS...THE MOISTURE REMAINS QUITE SHALLOW...BELOW 750MB. THE
LIFT ASSOCIATED WITH THE SHORTWAVE TROUGH DOES HELP PROVIDE LIFT
THROUGH THE COLUMN BUT WITH THE AIR ABOVE 750MB BEING SO EXTREMELY
DRY...THIS LIFT WILL NOT HAVE ANYTHING TO WORK WITH AND SO WILL HAVE
NO IMPACT ON THE FORECAST. IF THERE WOULD BE MOISTURE...COULD ARGUE
FOR NEEDING MENTION OF THUNDERSTORMS AS THE LAPSE RATES ARE QUITE
STEEP LEADING TO AT LEAST SOME INSTABILITY...BUT AGAIN NO MOISTURE
WILL PROHIBIT THE NEED FOR THUNDER MENTION. BACK TO THE LOW
LEVELS...THERE IS DECENT LIFT WITHIN THE SATURATED LAYER AND WITH
LIGHT EASTERLY WINDS CONTINUING THROUGH WEDNESDAY NIGHT...THE SLIGHT
UPSLOPE FLOW WILL HELP KEEP STRATUS/FOG/DRIZZLE POTENTIAL THROUGH
THE DAY. WITH THIS EXPECTATION...DON/T THINK TEMPERATURES WILL RISE
MUCH THROUGH THE DAY WEDNESDAY AND HAVE LOWERED HIGHS SUBSTANTIALLY.
THE FRONT WILL BE JUST SOUTH OF THE FORECAST AREA SO THERE MAY BE A
TIGHT GRADIENT WHERE CLOUDS/COLDER TEMPERATURES EXIST TO WHERE THERE
IS PLENTIFUL SUNSHINE AND HIGHS UP INTO THE 70S. BELIEVE THAT THIS
WILL BE SOUTH OF THE FORECAST AREA THROUGH.
THE WHOLE UPPER LEVEL SYSTEM CONTINUES TO MOVE EAST THROUGH THE DAY
THURSDAY...AND WHILE THEY ARE IN AGREEMENT WITH THE UPPER LOW
PASSING OVER THE REGION AND DUMPING SOME DECENT MOISTURE ACROSS THE
FORECAST AREA...THESE SOLUTIONS ARE DIFFERENT FROM PRIOR RUNS AS ALL
ARE NOW MOVING THE SYSTEM ACROSS THE AREA AS AN OPEN WAVE AND IN
TURNS MOVES IT ACROSS THE AREA FASTER...WITH PRECIPITATION ENDED BY
MID-DAY THURSDAY. THEY STILL PRODUCE QUITE A BIT OF QPF ON THE
NORTHWEST SIDE OF THE FORECAST AREA DESPITE MOVING ACROSS THE AREA
FASTER THAN WAS EARLIER THOUGHT. DID REMOVE MENTION OF
THUNDERSTORMS FOR WEDNESDAY NIGHT AND THURSDAY. THE FRONT WILL
REMAIN WELL SOUTH AND EAST OF THE LOCAL AREA AS THE SURFACE LOW
STAYS ACROSS KANSAS AS IT MOVES EASTWARD. THIS WILL KEEP THE
WARMER AIR...PLUS ANY MOISTURE ADVECTION/LIFT ALONG THE FRONT AWAY
FROM THE LOCAL AREA. AND...THE LOW LEVEL JET WILL BE WELL TO THE
EAST SO REALLY NOT CONCERNED ABOUT THUNDERSTORMS. THEN ON THURSDAY
AS THE SURFACE LOW ACROSS KANSAS TRANSITIONS INTO THE MISSISSIPPI
RIVER VALLEY THE PRESSURE GRADIENT WILL TIGHTEN...BRINGING STRONG
NORTHERLY WINDS TO THE FORECAST AREA. THIS WILL LEAD TO CONDITIONS
FEELING QUITE RAW AS APPARENT TEMPERATURES ARE LOOKING TO BE IN
THE 20S AND 30S. WITH THE COOLER AIR MOVING IN FROM THE NORTH...IT
IS LIKELY THAT THE PRECIPITATION WILL CHANGE OVER TO A RAIN/SNOW
MIX AND THEN OVER TO SNOW COMPLETELY OVER PARTS OF THE PANHANDLE.
DON/T THINK AMOUNTS WILL BE MUCH...BUT COULD SEE THE GROUND BECOME
WHITE FOR A SHORT PERIOD IN PLACES.
AGAIN AS THIS IS NOT MOVING THROUGH AS AN OPEN WAVE...IT WILL MOVE
THROUGH THE LOCAL AREA QUICKLY AND HAVE ENDED PRECIPITATION
CHANCES ABOUT 6 HOURS EARLIER THAN IN THE PRIOR FORECAST.
SHORTWAVE RIDGING BUILDS INTO THE CENTRAL PLAINS BRIEFLY FRIDAY
NIGHT...WHILE AN UPPER LOW IN THE SOUTHERN STREAM MOVES ACROSS THE
SOUTHERN CONUS AND NORTHERN MEXICO. MEANWHILE ANOTHER POTENT
SYSTEM MOVES INTO THE PACIFIC NORTHWEST. THESE SYSTEMS WILL BOTH
PROGRESS EASTWARD AND THERE IS SOME INDICATION THAT THEY MAY
ATTEMPT TO INTERACT EARLY NEXT WEEK WHICH COULD BRING ANOTHER WET
PERIOD TO THE FORECAST AREA FOR MONDAY AND TUESDAY. CONFIDENCE IS
NOT HIGH IN THIS OCCURRING RIGHT NOW SO WILL MAINTAIN LOW END
PRECIPITATION CHANCES FOR NOW.
ULTIMATELY WITH THE MORE ACTIVE PATTERN...WILL SEE MORE CHANCES
FOR PRECIPITATION...AND TEMPERATURES CLOSER TO NORMAL...ALTHOUGH
THERE WILL BE DAYS WITH HIGHER TEMPERATURES. HOWEVER THERE ARE NO
CURRENT INDICATIONS OF ANOTHER PERIOD OF WELL ABOVE NORMAL
TEMPERATURES FOR THE FORECAST AREA AT THIS TIME.
AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1142 PM CDT MON APR 6 2015
LIFR CEILINGS CURRENTLY AT THE KLBF AND KVTN TERMINALS IS FORECAST
TO PERSIST UNTIL 15Z. VSBY WILL LIKELY RANGE NEAR 1SM -DZ BR AT
KVTN WHILE LOWERING TO 3SM -DZ BR AT KLBF. AFTER 15Z...CEILINGS
AND VSBYS WILL IMPROVE TO IFR...AND TO MVFR AFTER 18Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...BROOKS
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1145 PM CDT MON APR 6 2015
.SHORT TERM...(TONIGHT THROUGH THURSDAY)
ISSUED AT 330 PM CDT MON APR 6 2015
FORECAST CONCERNS CONTINUE TO BE ON AND OFF PRECIPITATION CHANCES
THROUGH THE WEEK...TEMPERATURES...AND SEVERE POTENTIAL.
THE LOW CLOUDS MOVED IN OVERNIGHT...WITH SOME FOG AND DRIZZLE.
THE 12Z OAX SOUNDING WAS SATURATED TO 890MB/2500FT WITH 0.49PWAT.
A FEW STORMS DEVELOPED AROUND BOONE AND ANTELOPE COUNTIES AND
LIFTED TOWARD WAYNE...WITH A STRONGER CLUSTER NEAR WASHINGTON AND
BURT THAT LIFTED NORTHEAST ACROSS HARRISON...MONONA...AND SHELBY
WITH OTHERS IN SOUTHWEST IOWA. THE 12Z H5 MAP SHOWED A WEAK
SHORTWAVE WITH THIS FEATURE IN THE SOUTHWEST FLOW ALOFT. THE H5
CLOSED LOW WAS STILL OFF THE WASHINGTON/OREGON COAST WITH A BROAD
TROF. THERE WAS A WEAK WAVE IN THE FLOW AT H7 APPROACHING THE
LOCAL FORECAST AREA AT 12Z...WITH ANOTHER WEAK WAVE OVER COLORADO
AND YET FARTHER SOUTHWEST OVER SOUTHERN CALIFORNIA. THE H85
PATTERN HAD AN H85 LOW NEAR LBF WITH SOUTHWEST FLOW AHEAD OF IT
AND A POCKET OF 7C DEWPOINTS. THE 10-12DEG. H85 DEWPOINTS WERE
OVER SOUTHERN MO AND ARKANSAS INTO EASTERN OK. THE H7 DEWPOINTS
WERE BETTER OVER TN/AL/MS. THE +20 DEG. C H85 TEMPS WERE OVER TX
WITH THE THERMAL RIDGE NOSING TOWARD OMA AT +12 DEG C.
THE LATEST VISIBLE SATELLITE IMAGERY WAS CLOUDY MOST AREAS...WITH
SOME BUMPY CLOUDS NEAR SD INTO IOWA AND A FEW THINNER SPOTS TOWARD
FAIRBURY... THE SURFACE FRONT WAS NEAR YANKTON TO ONL WITH A
DRYLINE NEAR KGBD KANSAS AND THE WARM FRONT FROM SALINA TO
WICHITA WITH THE CLEARING NEAR THERE. TEMPERATURES WERE IN THE
50S TO LOWER 60S WITH 70S AND 80S SOUTH OF THE WARM FRONT.THE LOCAL
RADAR WAS MAINLY DRY WITH ECHOES TO THE NORTHEAST INTO IOWA.
STILL SOME PATCHY FOG WITH VSBYS 2 TO 4 MILES IN SPOTS.
TONIGHT...SURFACE LOW PRESSURE TRIES TO ORGANIZE A LITTLE FARTHER
SOUTH IN KANSAS WITH NORTHEAST FLOW PREVAILING ACROSS THE FORECAST
AREA. ONE THING TO WATCH WILL BE A 50KT LOW LEVEL JET THAT
INCREASES ACROSS KANSAS INTO MISSOURI. THE 4KM WRF HAS A CLUSTER OF
STORMS DEVELOPING AND MOVING ACROSS NORTHERN KANSAS AND MISSOURI.
THE RAP HAS SHOWERS/TSTORMS IN SOUTHEAST NEBRASKA. IN OUR
FORECAST AREA...ANY PRECIPITATION LOOKS SPOTTY. DO HAVE HIGHER
POPS IN THE SOUTHEAST AND ALSO IN THE NORTHEAST BY MORNING. THE
GFS DOES INCREASE INSTABILITY TOWARD 1000J/KG IN THE SOUTHEAST. ANY
STRONGER STORMS COULD PRODUCE SOME HAIL. THERE MAY BE AN ENHANCED
BAND OF LIGHT PRECIP IN NORTHEAST NEBRASKA BY MORNING NEAR AN
INVERTED TROF AND SOME SHORTWAVE ENERGY PASSES THROUGH.
TUESDAY...THE SURFACE LOW PRESSURE TRACKS NORTHEAST TOWARD SOUTHEAST
NEBRASKA OR NORTHEAST KANSAS...WITH A H85 CIRCULATION OVER THE
FORECAST AREA. THE PRECIPITATION (SHOWERS AND ISOLATED
THUNDERSTORMS) SHOULD MOVE ACROSS THE FORECAST AREA DURING THE
DAY. TEMPERATURES AGAIN SHOULD BE IN THE 50S...WITH 60S CLOSER TO
THE SURFACE LOW FALLS CITY COULD BREAK OUT TO THE LOWER 70S.
TUESDAY NIGHT INTO WEDNESDAY NIGHT AHEAD OF THE STRONGER
SHORTWAVE...FLOW BACKS AND RE-FOCUSES THE LOW LEVEL FLOW WITH
PRECIPITATION CHANCES AGAIN ON THE INCREASE. THE BETTER COVERAGE
SHOULD BE THE SOUTHEAST PART OF THE FORECAST AREA. THE DAY 3 SPC
OUTLOOK HAS THIS AREA ALSO IN THE SLIGHT RISK AND THIS SEEMS
REASONABLE AND WILL BE DEPENDENT ON THE THE SURFACE LOW TRACK. THE
NAM/EC IS NOT QUITE AS FAR NORTH AT THE GFS. SO THIS WILL BE
SOMETHING TO KEEP AN EYE ON.
THE FRONT PUSHES THROUGH THURSDAY WITH THE UPPER LEVEL TROF TO THE
WEST. POST-FRONT SHOWERS WILL CONTINUE INTO THURSDAY WITH
NORTHWEST WINDS.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 330 PM CDT MON APR 6 2015
THE STORM SYSTEM PULLS AWAY THURSDAY NIGHT. THERE IS A SMALL
CHANCE FOR SHOWERS/ISOLATED THUNDERSTORMS FRIDAY NIGHT AND
SATURDAY. ON AND OFF PRECIPITATION CHANCES CONTINUE INTO THE
WEEKEND.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1145 PM CDT MON APR 6 2015
WIDESPREAD IFR/LIFR CIGS AND IFR VSBYS WILL CONTINUE THROUGH ABOUT
18Z AS AREAS OF FOG AND DRIZZLE PERSIST. SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS ARE EXPECTED TO DEVELOP IN CENTRAL NEBRASKA
BEFORE 12Z...THEN SPREAD EAST TOWARD KOFK AND KLNK BY 12Z THEN
KOMA BY 14Z. EXPECT ABOUT A 6 HOUR PERIOD OF POTENTIAL SHOWERS AND
ISOLATED THUNDERSTORMS. SOME LIGHT IMPROVEMENT IN VSBYS AND CIGS
TO MVFR ARE IS POSSIBLE BETWEEN 18Z AND 00Z...THEN DETERIORATING
CONDITIONS TO IFR ARE FORECAST AFTER 00Z.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...DERGAN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
205 AM EDT TUE APR 7 2015
.SYNOPSIS...
A SLOW MOVING FRONTAL SYSTEM WILL KEEP THE WEATHER UNSETTLED FOR
MUCH OF THE UPCOMING WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
945 PM UPDATE...
MAIN CHANGE THIS FORECAST RUN WAS TO PULL WAY BACK ON THE POPS
DURING THE SECOND HALF OF THE OVERNIGHT AND INTO TUESDAY MORNING.
MAIN WAVE OF PRECIP IS MOVING THROUGH THE FA ATTM AND IS PROGGED
TO WEAKEN AND DIMINISH AFTER MIDNIGHT. HRRR SEEMS TO HAVE A GOOD
HANDLE ON THE CURRENT TRENDS.
WE ARE SLOWLY INGESTING NEW MODEL/MOS DATA AFTER THE AWIPS II
INSTALL EARLIER, SO WE ARE A LITTLE LIMITED THIS EVENING ON WHAT
DATA WE CAN UTILIZE TO BLEND WITH.
1 PM UPDATE...
CLOUDS ARE BEGINNING TO ENCROACH FROM THE WEST ASSOCIATED WITH A
SERIES OF SHORTWAVES THAT ARE BEGINNING TO EJECT AND RACE EAST
OUT OF THE LARGE SCALE TROUGH OVER THE WESTERN US. THE FIRST
SHOWERS REACHING THE GROUND CAN BE SEEN OVER NORTHERN OHIO...AND
GUIDANCE SHOWS THE MOISTURE CONTINUING TO SURGE INTO THE REGION ON
A STRONG LOW LEVEL SWLY FLOW. GEFS/SREF SHOW PWATS RISING TO 1-2
ST DEV ABOVE NORMAL...CONTINUING INTO AT LEAST TUESDAY.
SREF SHOWS INCREASING CHANCES FOR RAIN EARLY TONIGHT...WITH
LIKELY TO CATEGORICAL POPS DEVELOPING BETWEEN 21-03Z. GEFS IS A
LITTLE LESS AGGRESSIVE BUT STILL SUGGESTS MOST IF NOT ALL
LOCATIONS WILL SEE MEASURABLE RAINS OVERNIGHT. OPERATIONAL RUNS
OF THE GFS/NAM ARE A LITTLE MORE DETAILED...HINTING AT SOME SORT
OF WAVE FORMING ALONG THE SLOW MOVING WARM FRONT AND BRINGING THE
INITIAL SURGE OF SHOWERS...WITH SOMEWHAT OF A LULL POSSIBLE FOR
THE SECOND HALF OF THE OVERNIGHT...ESPECIALLY OVER NORTHERN
AREAS.
LOWS WILL RANGE FROM THE CHILLY MID 30S OVER THE NORTH TO AROUND
50 IN THE FAR SOUTH.
&&
.SHORT TERM /TONIGHT THROUGH 6 PM WEDNESDAY/...
1 PM UPDATE...
COLD HIGH PRESSURE ANCHORED TO OUR NORTH AND THE WAVY BOUNDARY
TO OUR SOUTH WILL BE THE WEATHER DRIVERS FOR THE SHORT TERM. THE
GFS SUPPRESSES MOST OF THE PRECIP SOUTH TO AROUND THE NY/PA
BORDER BY LATER TUESDAY NIGHT EARLY WED AM...WHILE THE OPERATIONAL
NAM AND ECMWF SHOW LIGHT QPF BEING MORE GENEROUSLY SPREAD ABOUT
THE REGION.
THE GEFS IS A LITTLE LESS OPTIMISTIC THAN ITS OPERATIONAL
COUNTERPART WHILE THE SREF SUGGESTS THE NAM MAY BE TOO DRY. WILL
USE A BLEND OF POPS FOR THE PERIOD WHICH LENDS SMALL CONFIDENCE TO
ACTUALLY TRYING TO TIME WHEN THE BEST CHANCES FOR RAIN OR NO RAIN
WILL END UP BEING.
LOCAL RIVERS AND STREAMS ARE RUNNING HIGH...SO RAINFALL AMOUNTS
NEED TO BE MONITORED FOR POSSIBLE PROBLEMS. AT THIS POINT...NO
FLOODING IS EXPECTED.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
UPDATED 300 PM...BLENDED PREVIOUS FORECAST WITH THE LATEST MEDIUM
RANGE/WPC GUIDANCE WHICH RESULTED IN MINOR CHANGES. KEPT RISK FOR
FREEZING RAIN AROUND MID-WEEK WITH HIGHEST POPS ON DAY 5/FRI WITH
A SHARP COLD FRONTAL PASSAGE. OVERALL AN ACTIVE AND WET PERIOD
THROUGH THE END OF THE WEEK BEFORE THINGS DRY OUT BEHIND THE FRONT
THIS WEEKEND.
PREVIOUS DISCUSSION...
FORECAST ADJUSTED FOR TRENDS AND LATEST WPC
GUIDANCE. A COUPLE THINGS TO NOTE. ONE IS THAT STRONG HIGH
PRESSURE WILL BECOME CENTERED OVER FAR NORTHERN NEW ENGLAND-LOWER
ST. LAWRENCE SEAWAY LATE WEDNESDAY NIGHT INTO EARLY
THURSDAY...WHICH IS A GOOD SET UP FOR COLD AIR DAMMING. THERE
APPEARS TO BE SOME POTENTIAL FOR LIGHT FREEZING RAIN HIGHER
ELEVATIONS OF THE NORTHEASTERN ZONES DURING THAT TIME...THOUGH
PRECIP CHANCES ITSELF NOT THAT HIGH AND AMOUNTS IF ANY WOULD BE
VERY LIGHT. OTHERWISE THURSDAY- FRIDAY PERIOD LOOKS WET WITH MOIST
WARM AIR ADVECTION ALLOWING TEMPERATURES TO TREND ABOVE
CLIMATOLOGY INTO THE WEEKEND. OTHER THING THAT LATEST OPERATIONAL
GFS-ECMWF RUNS INCREASE CONFIDENCE IN LARGE SURFACE HIGH
DOMINATING SECOND HALF OF THE WEEKEND...FOR DRY AND MILD
CONDITIONS SUNDAY.
PREVIOUS DISCUSSION...
CLOSELY FOLLOWED WPC GUIDANCE. A WET PATTERN CONTINUES AS BROAD SW
FLOW ALOFT PREVAILS THROUGHOUT THE EXTENDED FORECAST PERIOD. THIS
PATTERN ALOFT ALLOWS FOR MULTIPLE SHORTWAVES WITHIN THE UPPER LVL
FLOW TO PASS OVER THE REGION BRINGING A CHANCE FOR RAIN SHOWERS
EACH DAY. ATTM... THE BEST CHANCE FOR RAIN SHOWERS OVER THE REGION
WILL BE THURS NIGHT THRU FRIDAY NIGHT. AS WE ARE AT THE TAIL END
OF WINTER... THERE IS STILL A CHANCE AT NIGHT THAT SOME OF THESE
SHOWERS COULD TRANSITION OVER TO SNOW. NO MAJOR ACCUMULATIONS ARE
EXPECTED THROUGH THE EXTENDED. TEMPERATURES DURING THIS TIME FRAME
ARE EXPECTED TO BE AT OR ABOVE THE SEASONAL NORM.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
06Z UPDATE...
AS HAS BEEN THE CASE THE LAST FEW DAYS...FORECAST REMAINS
CHALLENGING WITH VARYING GUIDANCE /SOME MUCH TOO
PESSIMISTIC/...FINE DETAILS...AND THUS LOWER CONFIDENCE THAN
USUAL. IN THE BIG PICTURE...A FRONTAL BOUNDARY IS SAGGING
SOUTHWARD THROUGH THE AREA AND THEN STALLING DURING THIS TAF
PERIOD. FAIRLY QUIET AT THE MOMENT WITH VERY SPORADIC SHOWERS NOW
AROUND KAVP...BUT WAVES MOVING ALONG THE FRONT WILL CAUSE
ADDITIONAL SHOWERS TO DEVELOP DURING THE DAY...ESPECIALLY KITH-
KBGM-KELM-KAVP. AS COOLER AIR CONTINUES TO ADVECT IN...LINGERING
MOISTURE WILL CONDENSE AND BECOME TRAPPED UNDER SHALLOW
INVERSION...WHICH ALONG WITH MOISTURE FROM PASSING SHOWERS SHOULD
ALLOW MVFR CIGS TO DEVELOP KITH-KBGM-KAVP-KELM...EVENTUALLY FUEL
ALT. IFR NOT OUT OF THE QUESTION /KBGM BEST CHANCE...KAVP
POSSIBLE AS WELL LATE DUE TO MOISTURE AND FAVORABLE LIGHT
NORTHEAST WIND/. KRME-KSYR APPEAR TO BE MAINLY VFR THIS
PERIOD...BUT EARLY THIS MORNING WE WILL HAVE TO WATCH FOR
POTENTIAL THIN OVC LAYER NEAR FUEL ALT-TO-MVFR LEVEL...BEFORE
DRIER LOW LEVEL AIR ELIMINATES THE POSSIBILITY. NOT CONFIDENT
ENOUGH TO INCLUDE IN TAF AT THIS TIME. WINDS GENERALLY VARIABLE TO
LIGHT N/NE/E...SEE TAFS FOR SPECIFICS.
.OUTLOOK...
LATE TUE NGT-FRI...BUSY PATTERN WITH WAFFLING FRONTAL BOUNDARY
REMAINING IN THE VICINITY...AND WAVES OF SHRA PLUS ASSOCIATED
RESTRICTIONS MOVING ALONG IT. SLIGHT CHC TSRA AS WELL FRI.
SAT...MAINLY VFR BUT ISOLATED -SHRA STILL POSSIBLE.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...DJP
SHORT TERM...
LONG TERM...
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
330 AM EDT TUE APR 7 2015
.SYNOPSIS...AN UPPER LEVEL DISTURBANCE WILL PASS OVER THE AREA THIS
MORNING. A WARM FRONT WILL LIFT NORTHWARD THROUGH THE REGION LATER
TODAY... KEEPING A WARM MOIST AIR MASS OVER NORTH CAROLINA THROUGH
WEDNESDAY. A BACKDOOR COLD FRONT TO OUR NORTH WILL DIP SOUTHWARD
INTO NORTHEAST NORTH CAROLINA LATE WEDNESDAY... THEN LIFT BACK NORTH
OF THE AREA ON THURSDAY.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 250 AM TUESDAY...
AN UNSETTLED PERIOD OF WEATHER BEGINS TODAY AND EXTENDS THROUGH LATE
IN THE WORK WEEK. A SHORTWAVE ALOFT (MOST EVIDENT AT 850-700 MB) AND
RESULTANT AREA OF SHOWERS NOW MOVING THROUGH THE CWA WILL BE MOVING
TO OUR EAST BY MID TO LATE MORNING... ALTHOUGH THE HIGH WATER
CONTENT (PW NEAR 200% OF NORMAL) AND POTENTIAL FOR WEAK INSTABILITY
NECESSITATES LEAVING IN A LOW CHANCE FOR A SHOWER OR TWO BEHIND THIS
CURRENT SHOWER AREA FROM LATE MORNING THROUGH EARLY AFTERNOON... IN
ACCORD WITH THE LATEST HRRR MODEL RUNS... DESPITE SOME POST-WAVE
SUBSIDENCE. WE SHOULD SEE AN UPTICK IN INSTABILITY THIS AFTERNOON...
ALTHOUGH THIS SHOULD REMAIN ON THE WEAK SIDE WITH NAM MUCAPE OF 500-
750 J/KG AT MOST... AND DEEP LAYER SHEAR WILL BE MARGINAL AT AROUND
25-30 KTS. LARGE SCALE MODELS SHOW A WEAK MID LEVEL PERTURBATION
MOVING IN FROM THE WEST LATE TODAY INTO EARLY THIS EVENING... AND
THIS SEEMS TO CORRELATE WITH A BROKEN BAND OF CONVECTION NOW
EXTENDING FROM LOWER MI TO A MORE ORGANIZED COMPLEX OVER SRN IL TO
AR/ERN TX. EXTRAPOLATION OF THIS CONVECTION AND ITS ACCOMPANYING
STRONG BUT WANING UPPER DIVERGENCE BRINGS IT INTO WRN NC EARLY THIS
EVENING... A TIMING SUPPORTED BY THE HRRR AND HI-RES ARW/NMM MODELS.
WILL REFLECT THE RELATIVE LULL IN PRECIP BEFORE RAMPING BACK UP TO
HIGH CHANCE/LIKELY POPS LATER THIS AFTERNOON INTO EARLY/MID
EVENING... LEAVING IT AS PRIMARILY SHOWERS (DUE TO UNIMPRESSIVE
FORECAST CAPE/SHEAR) AND ISOLATED STORMS. EXPECT PRECIP CHANCES TO
DROP BACK TO A 10-20% CHANCE AT MOST OVERNIGHT WITH LOSS OF HEATING
AND POST-WAVE SINKING AIR HELPING TO DRY OUT THE MID-UPPER LEVELS
SOMEWHAT. THE MILD START TO THE DAY AND ANTICIPATED BREAK IN THE
PRECIP ALONG WITH THICKNESSES NEARLY 20 M ABOVE NORMAL SHOULD ALLOW
TEMPS TO PEAK TODAY IN THE 73-79 RANGE DESPITE PLENTY OF CLOUDS.
WARM LOWS TONIGHT OF 59-65 WITH AREAS OF FOG. -GIH
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 325 AM TUESDAY...
WE`LL BE FIRMLY IN THE WARM SECTOR WED WITH PW VALUES HOLDING NEAR
200% OF NORMAL. WE SHOULD INITIALLY SEE WEAK SUBSIDENCE BEHIND THIS
EVENING`S WAVE AS IT SHIFTS OFF THE NC/VA COAST... HOWEVER AS IT
INDUCES WEAK BUT IMPORTANT CYCLOGENESIS JUST OFF THE COAST... THE
FLOW AROUND THIS LOW WILL HELP DRAW THE SURFACE FRONTAL ZONE TO OUR
NORTH (NOW EXTENDING ROUGHLY WEST-EAST JUST NORTH OF THE OH VALLEY
INTO THE NYC AREA) TO THE SOUTH INTO VA/NC LATE WED. THE GFS REMAINS
THE MOST BULLISH IN PUSHING THE FRONTAL ZONE WELL SOUTHWARD INTO THE
SRN CWA... WHEREAS THE NAM (WITH ITS MORE-OFFSHORE LOW) AND THE
ECMWF (MUCH WEAKER LOW) HOLD IT NORTH OF THE NC/VA BORDER OR PERHAPS
DIP IT JUST BARELY INTO OUR NE CWA. HAVE OPTED TO FAVOR THE LATTER
SOLUTION BASED ON THE FAR-NORTH POSITION OF THE PARENT HIGH/COLD AIR
AND LOW CONFIDENCE IN THE GFS`S STRONGER AND MORE WESTWARD LOW.
FORECAST MUCAPE PEAKS AT 750-1500 J/KG ON THE GFS AND 1500-2500 J/KG
ON THE NAM WED AFTERNOON... BUT WITH CONTINUED MODEST DEEP LAYER
SHEAR OF 25-30 KTS. GIVEN THE MOISTURE IN PLACE THOUGH... WILL RAMP
UP POPS TO GOOD CHANCE FOR AFTERNOON INTO EARLY EVENING... TRENDING
BACK DOWN TO 20-30% CHANCE FROM LATE EVENING ONWARD THROUGH WED
NIGHT WITH LOWERING INSTABILITY... BUT WE MAY STILL SEE SCATTERED
SHOWERS CONCENTRATED NEAR AND JUST SOUTH OF THE FRONTAL ZONE... OVER
NRN CWA. VERY WARM THICKNESSES SUPPORT HIGHS OF 77-85 (NE TO SW).
ANOTHER NIGHT OF WARM LOWS IN THE UPPER 50S TO LOWER 60S... WITH
REDUCED CONFIDENCE... AS A FARTHER-SOUTH PENETRATION OF THE FRONT
WOULD MEAN COOLER TEMPS IN THE NE CWA. -GIH
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 255 AM MONDAY...
STILL A LARGE AMOUNT OF UNCERTAINTY WITH THE FIRST PART OF THE LONG
TERM AS IT IS STILL UNCLEAR HOW FAR SOUTH A BACKDOOR COLD FRONT WILL
PUSH ON THURSDAY. HIGH SURFACE PRESSURE APPEARS TO BE TOO FAR TO THE
NORTHEAST TO PRODUCE A STRONG CAD EVENT THIS TIME OF YEAR...BUT IT
MAY HAVE SOME HELP AS LOW PRESSURE OFF THE MID-ATLANTIC COAST COULD
WORK IN TANDEM WITH THE HIGH TO FUNNEL COLD AIR DOWN INTO THE
CAROLINAS. THE STRENGTH AND LOCATION OF THIS LOW COULD BE THE KEY TO
THE FORECAST. AT THIS TIME THE ECMWF AND THE NAM BOTH HAVE THE LOW
FAIRLY FAR OFFSHORE AND WEAKER THAN THE GFS SOLUTION WHICH PUTS THE
LOW MUCH FURTHER SOUTHWEST OFF OF THE NORTHERN OUTER BANKS. THIS
LATE IN THE YEAR WOULD EXPECT THE GFS SOLUTION TO BE TOO STRONG WITH
THE CAD SCENARIO AND THUS WILL FAVOR A NON-GFS SOLUTION...RESULTING
IN WARMER TEMPS FOR THURSDAY THAN MOS GUIDANCE. ONLY LIGHT RAIN
EXPECTED UNTIL LATER IN THE EVENING WHEN MORE RETURN FLOW MOISTURE
MOVES OVER CENTRAL NC. IT SHOULD BE NOTED THAT IF THE GFS SOLUTION
IS CORRECT THE FORECASTED TEMPERATURES WILL BUST ON THE HIGH SIDE.
MODELS COME INTO BETTER AGREEMENT FOR THE END OF THE WEEK WITH A
COLD FRONT PROGGED TO MOVE ACROSS THE STATE FRIDAY EVENING THROUGH
SATURDAY AFTERNOON. WHILE THE EVENT DOES NOT LOOK OVERWHELMING AS
FAR AS SEVERE POTENTIAL IS CONCERNED...THERE WILL BE INSTABILITY
BETWEEN 500-1000 J/KG AND BULK SHEAR VALUES BETWEEN 20-30 KTS WHICH
IS PLENTY FOR CONVECTIVE SHOWERS AND THUNDERSTORMS. ADD SOME
INCREASED FORCING FOR ASCENT AHEAD OF THE FRONT AND THE SEVERE
POTENTIAL INCREASES SLIGHTLY...ENOUGH TO WARRANT A 15% RISK IN THE
DAY 5 CONVECTIVE OUTLOOK FROM SPC.
SURFACE HIGH PRESSURE MOVES IN BEHIND THE FRONT ON SATURDAY NIGHT
WHICH BRINGS IN A COOLER AND DRIER AIRMASS FOR ON SUNDAY AS THE HIGH
SHIFTS OFFSHORE. RAIN RETURNS FOR MONDAY HOWEVER AS A STRONG LOW
PRESSURE SYSTEM OVER THE UPPER MIDWEST USHERS A WARM FRONT OVER
CENTRAL NC FROM THE SOUTHWEST. CONDITIONS WILL REMAIN FAIRLY SOGGY
UNTIL PASSAGE OF THE TRAILING COLD FRONT SOMETIME ON TUESDAY
AFTERNOON.
TEMPERATURES THROUGH THE PERIOD WILL FEATURE HIGHS IN THE MID 70S TO
MID 80S AND LOWS IN THE MID 50S TO MID 60S.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 200 AM TUESDAY...
PRIMARY AVIATION CONCERN NEXT 24 HRS: GOOD CHANCE OF CIGS DROPPING
TO MVFR THEN IFR EARLY THIS MORNING... THEN MVFR CIGS ARE EXPECTED
THIS AFTERNOON. POTENTIAL IFR/LIFR CIGS/VSBYS TOWARD THE END OF THE
FORECAST PERIOD (AFTER 03Z TONIGHT).
AVIATION CONDITIONS WILL BECOME MORE UNSETTLED AND ADVERSE THIS
MORNING. A PASSING DISTURBANCE ALOFT EARLY THIS MORNING WILL LEAD TO
A PERIOD OF SHOWERS WITH MVFR VSBYS IN THE FIRST SEVERAL HOURS OF
THE FORECAST... MOVING WEST TO EAST... WITH CIGS LIKELY TO DROP TO
MVFR THEN IFR NEAR OR JUST BEFORE SUNRISE. RECOVERY TO MAINLY MVFR
CIGS IS EXPECTED LATER THIS MORNING... THEN THE NORTHWARD MOVEMENT
OF A WARM FRONTAL ZONE THROUGH THE AREA TODAY WITH ANOTHER
DISTURBANCE WILL BRING ANOTHER CHANCE OF SHOWERS WITH MVFR
VSBYS/CIGS MAINLY DURING THE MID TO LATE AFTERNOON. BY EARLY-MID
EVENING... A PERIOD OF VFR CONDITIONS IS POSSIBLE BEHIND THE
DEPARTING DISTURBANCE... BUT EXPECT DEVELOPMENT OF FOG AND LOW
CLOUDS TOWARD MIDNIGHT... LEADING TO AREAS OF IFR/LIFR CONDITIONS
TOWARD THE END OF THE TAF VALID PERIOD.
LOOKING BEYOND 06Z EARLY WED MORNING: IFR/LIFR CONDITIONS ARE
EXPECTED TO EXTEND UNTIL SUNRISE WED... THEN LIFT TO MVFR BY NOON
AND TO VFR DURING THE EARLY-MID AFTERNOON. HEATING AND INSTABILITY
WILL LEAD TO SCATTERED SHOWERS AND A FEW STORMS WED AFTERNOON WITH
POTENTIAL SUB-VFR CONDITIONS. REDEVELOPMENT OF IFR/LIFR FOG/STRATUS
IS POSSIBLE WED NIGHT INTO THU MORNING. ADDITIONAL SHOWERS/STORMS
THU AFTERNOON MAY BRING BRIEF SUB-VFR CONDITIONS. MORE WIDESPREAD
AND ORGANIZED SHOWERS AND STORMS ARE ANTICIPATED AHEAD OF A COLD
FRONT APPROACHING LATE FRI. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...ELLIS
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
254 AM EDT TUE APR 7 2015
.SYNOPSIS...AN UPPER LEVEL DISTURBANCE WILL PASS OVER THE AREA THIS
MORNING. A WARM FRONT WILL LIFT NORTHWARD THROUGH THE REGION LATER
TODAY... KEEPING A WARM MOIST AIR MASS OVER NORTH CAROLINA THROUGH
WEDNESDAY. A BACKDOOR COLD FRONT TO OUR NORTH WILL DIP SOUTHWARD
INTO NORTHEAST NORTH CAROLINA LATE WEDNESDAY... THEN LIFT BACK NORTH
OF THE AREA ON THURSDAY.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 250 AM TUESDAY...
AN UNSETTLED PERIOD OF WEATHER BEGINS TODAY AND EXTENDS THROUGH LATE
IN THE WORK WEEK. A SHORTWAVE ALOFT (MOST EVIDENT AT 850-700 MB) AND
RESULTANT AREA OF SHOWERS NOW MOVING THROUGH THE CWA WILL BE MOVING
TO OUR EAST BY MID TO LATE MORNING... ALTHOUGH THE HIGH WATER
CONTENT (PW NEAR 200% OF NORMAL) AND POTENTIAL FOR WEAK INSTABILITY
NECESSITATES LEAVING IN A LOW CHANCE FOR A SHOWER OR TWO BEHIND THIS
CURRENT SHOWER AREA FROM LATE MORNING THROUGH EARLY AFTERNOON... IN
ACCORD WITH THE LATEST HRRR MODEL RUNS... DESPITE SOME POST-WAVE
SUBSIDENCE. WE SHOULD SEE AN UPTICK IN INSTABILITY THIS AFTERNOON...
ALTHOUGH THIS SHOULD REMAIN ON THE WEAK SIDE WITH NAM MUCAPE OF 500-
750 J/KG AT MOST... AND DEEP LAYER SHEAR WILL BE MARGINAL AT AROUND
25-30 KTS. LARGE SCALE MODELS SHOW A WEAK MID LEVEL PERTURBATION
MOVING IN FROM THE WEST LATE TODAY INTO EARLY THIS EVENING... AND
THIS SEEMS TO CORRELATE WITH A BROKEN BAND OF CONVECTION NOW
EXTENDING FROM LOWER MI TO A MORE ORGANIZED COMPLEX OVER SRN IL TO
AR/ERN TX. EXTRAPOLATION OF THIS CONVECTION BRINGS IT INTO WRN NC
EARLY THIS EVENING... A TIMING SUPPORTED BY THE HRRR AND HI-RES
ARW/NMM MODELS. WILL REFLECT THE RELATIVE LULL IN PRECIP BEFORE
RAMPING BACK UP TO HIGH CHANCE/LIKELY POPS LATER THIS AFTERNOON INTO
EARLY/MID EVENING... LEAVING IT AS PRIMARILY SHOWERS (DUE TO
UNIMPRESSIVE FORECAST CAPE/SHEAR) AND ISOLATED STORMS. EXPECT PRECIP
CHANCES TO DROP BACK TO A 20-30% CHANCE AT MOST OVERNIGHT WITH LOSS
OF HEATING AND POST-WAVE SINKING AIR HELPING TO DRY OUT THE MID-
UPPER LEVELS SOMEWHAT. THE MILD START TO THE DAY AND ANTICIPATED
BREAK IN THE PRECIP ALONG WITH THICKNESSES NEARLY 20 M ABOVE NORMAL
SHOULD ALLOW TEMPS TO PEAK TODAY IN THE 73-79 RANGE DESPITE PLENTY
OF CLOUDS. WARM LOWS TONIGHT OF 59-65. -GIH
&&
.SHORT TERM / /...
AS OF 345 PM MONDAY...
TO BE UPDATED SHORTLY.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 255 AM MONDAY...
STILL A LARGE AMOUNT OF UNCERTAINTY WITH THE FIRST PART OF THE LONG
TERM AS IT IS STILL UNCLEAR HOW FAR SOUTH A BACKDOOR COLD FRONT WILL
PUSH ON THURSDAY. HIGH SURFACE PRESSURE APPEARS TO BE TOO FAR TO THE
NORTHEAST TO PRODUCE A STRONG CAD EVENT THIS TIME OF YEAR...BUT IT
MAY HAVE SOME HELP AS LOW PRESSURE OFF THE MID-ATLANTIC COAST COULD
WORK IN TANDEM WITH THE HIGH TO FUNNEL COLD AIR DOWN INTO THE
CAROLINAS. THE STRENGTH AND LOCATION OF THIS LOW COULD BE THE KEY TO
THE FORECAST. AT THIS TIME THE ECMWF AND THE NAM BOTH HAVE THE LOW
FAIRLY FAR OFFSHORE AND WEAKER THAN THE GFS SOLUTION WHICH PUTS THE
LOW MUCH FURTHER SOUTHWEST OFF OF THE NORTHERN OUTER BANKS. THIS
LATE IN THE YEAR WOULD EXPECT THE GFS SOLUTION TO BE TOO STRONG WITH
THE CAD SCENARIO AND THUS WILL FAVOR A NON-GFS SOLUTION...RESULTING
IN WARMER TEMPS FOR THURSDAY THAN MOS GUIDANCE. ONLY LIGHT RAIN
EXPECTED UNTIL LATER IN THE EVENING WHEN MORE RETURN FLOW MOISTURE
MOVES OVER CENTRAL NC. IT SHOULD BE NOTED THAT IF THE GFS SOLUTION
IS CORRECT THE FORECASTED TEMPERATURES WILL BUST ON THE HIGH SIDE.
MODELS COME INTO BETTER AGREEMENT FOR THE END OF THE WEEK WITH A
COLD FRONT PROGGED TO MOVE ACROSS THE STATE FRIDAY EVENING THROUGH
SATURDAY AFTERNOON. WHILE THE EVENT DOES NOT LOOK OVERWHELMING AS
FAR AS SEVERE POTENTIAL IS CONCERNED...THERE WILL BE INSTABILITY
BETWEEN 500-1000 J/KG AND BULK SHEAR VALUES BETWEEN 20-30 KTS WHICH
IS PLENTY FOR CONVECTIVE SHOWERS AND THUNDERSTORMS. ADD SOME
INCREASED FORCING FOR ASCENT AHEAD OF THE FRONT AND THE SEVERE
POTENTIAL INCREASES SLIGHTLY...ENOUGH TO WARRANT A 15% RISK IN THE
DAY 5 CONVECTIVE OUTLOOK FROM SPC.
SURFACE HIGH PRESSURE MOVES IN BEHIND THE FRONT ON SATURDAY NIGHT
WHICH BRINGS IN A COOLER AND DRIER AIRMASS FOR ON SUNDAY AS THE HIGH
SHIFTS OFFSHORE. RAIN RETURNS FOR MONDAY HOWEVER AS A STRONG LOW
PRESSURE SYSTEM OVER THE UPPER MIDWEST USHERS A WARM FRONT OVER
CENTRAL NC FROM THE SOUTHWEST. CONDITIONS WILL REMAIN FAIRLY SOGGY
UNTIL PASSAGE OF THE TRAILING COLD FRONT SOMETIME ON TUESDAY
AFTERNOON.
TEMPERATURES THROUGH THE PERIOD WILL FEATURE HIGHS IN THE MID 70S TO
MID 80S AND LOWS IN THE MID 50S TO MID 60S.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 200 AM TUESDAY...
PRIMARY AVIATION CONCERN NEXT 24 HRS: GOOD CHANCE OF CIGS DROPPING
TO MVFR THEN IFR EARLY THIS MORNING... THEN MVFR CIGS ARE EXPECTED
THIS AFTERNOON. POTENTIAL IFR/LIFR CIGS/VSBYS TOWARD THE END OF THE
FORECAST PERIOD (AFTER 03Z TONIGHT).
AVIATION CONDITIONS WILL BECOME MORE UNSETTLED AND ADVERSE THIS
MORNING. A PASSING DISTURBANCE ALOFT EARLY THIS MORNING WILL LEAD TO
A PERIOD OF SHOWERS WITH MVFR VSBYS IN THE FIRST SEVERAL HOURS OF
THE FORECAST... MOVING WEST TO EAST... WITH CIGS LIKELY TO DROP TO
MVFR THEN IFR NEAR OR JUST BEFORE SUNRISE. RECOVERY TO MAINLY MVFR
CIGS IS EXPECTED LATER THIS MORNING... THEN THE NORTHWARD MOVEMENT
OF A WARM FRONTAL ZONE THROUGH THE AREA TODAY WITH ANOTHER
DISTURBANCE WILL BRING ANOTHER CHANCE OF SHOWERS WITH MVFR
VSBYS/CIGS MAINLY DURING THE MID TO LATE AFTERNOON. BY EARLY-MID
EVENING... A PERIOD OF VFR CONDITIONS IS POSSIBLE BEHIND THE
DEPARTING DISTURBANCE... BUT EXPECT DEVELOPMENT OF FOG AND LOW
CLOUDS TOWARD MIDNIGHT... LEADING TO AREAS OF IFR/LIFR CONDITIONS
TOWARD THE END OF THE TAF VALID PERIOD.
LOOKING BEYOND 06Z EARLY WED MORNING: IFR/LIFR CONDITIONS ARE
EXPECTED TO EXTEND UNTIL SUNRISE WED... THEN LIFT TO MVFR BY NOON
AND TO VFR DURING THE EARLY-MID AFTERNOON. HEATING AND INSTABILITY
WILL LEAD TO SCATTERED SHOWERS AND A FEW STORMS WED AFTERNOON WITH
POTENTIAL SUB-VFR CONDITIONS. REDEVELOPMENT OF IFR/LIFR FOG/STRATUS
IS POSSIBLE WED NIGHT INTO THU MORNING. ADDITIONAL SHOWERS/STORMS
THU AFTERNOON MAY BRING BRIEF SUB-VFR CONDITIONS. MORE WIDESPREAD
AND ORGANIZED SHOWERS AND STORMS ARE ANTICIPATED AHEAD OF A COLD
FRONT APPROACHING LATE FRI. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...VINCENT
LONG TERM...ELLIS
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
250 AM EDT TUE APR 7 2015
.SYNOPSIS...AN UPPER LEVEL DISTURBANCE WILL PASS OVER THE AREA THIS
MORNING. A WARM FRONT WILL LIFT NORTHWARD THROUGH THE REGION LATER
TODAY... KEEPING A WARM MOIST AIR MASS OVER NORTH CAROLINA THROUGH
WEDNESDAY. A BACKDOOR COLD FRONT TO OUR NORTH WILL DIP SOUTHWARD
INTO NORTHEAST NORTH CAROLINA LATE WEDNESDAY... THEN LIFT BACK NORTH
OF THE AREA ON THURSDAY.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 250 AM TUESDAY...
AN UNSETTLED PERIOD OF WEATHER BEGINS TODAY AND EXTENDS THROUGH LATE
IN THE WORK WEEK. A SHORTWAVE ALOFT (MOST EVIDENT AT 850-700 MB) AND
RESULTANT AREA OF SHOWERS NOW MOVING THROUGH THE CWA WILL BE MOVING
TO OUR EAST BY MID TO LATE MORNING... ALTHOUGH THE HIGH WATER
CONTENT (PW NEAR 200% OF NORMAL) AND POTENTIAL FOR WEAK INSTABILITY
NECESSITATES LEAVING IN A LOW CHANCE FOR A SHOWER OR TWO BEHIND THIS
CURRENT SHOWER AREA FROM LATE MORNING THROUGH EARLY AFTERNOON... IN
ACCORD WITH THE LATEST HRRR MODEL RUNS... DESPITE SOME POST-WAVE
SUBSIDENCE. WE SHOULD SEE AN UPTICK IN INSTABILITY THIS AFTERNOON...
ALTHOUGH THIS SHOULD REMAIN ON THE WEAK SIDE WITH NAM MUCAPE OF 500-
750 J/KG AT MOST... AND DEEP LAYER SHEAR WILL BE MARGINAL AT AROUND
25-30 KTS. LARGE SCALE MODELS SHOW A WEAK MID LEVEL PERTURBATION
MOVING IN FROM THE WEST LATE TODAY INTO EARLY THIS EVENING... AND
THIS SEEMS TO CORRELATE WITH A BROKEN BAND OF CONVECTION NOW
EXTENDING FROM LOWER MI TO A MORE ORGANIZED COMPLEX OVER SRN IL TO
AR/ERN TX. EXTRAPOLATION OF THIS CONVECTION BRINGS IT INTO WRN NC
EARLY THIS EVENING... A TIMING SUPPORTED BY THE HRRR AND HI-RES
ARW/NMM MODELS. WILL REFLECT THE RELATIVE LULL IN PRECIP BEFORE
RAMPING BACK UP TO HIGH CHANCE/LIKELY POPS LATER THIS AFTERNOON INTO
EARLY/MID EVENING... LEAVING IT AS PRIMARILY SHOWERS (DUE TO
UNIMPRESSIVE FORECAST CAPE/SHEAR) AND ISOLATED STORMS. EXPECT PRECIP
CHANCES TO DROP BACK TO A 20-30% CHANCE AT MOST OVERNIGHT WITH LOSS
OF HEATING AND POST-WAVE SINKING AIR HELPING TO DRY OUT THE MID-
UPPER LEVELS SOMEWHAT. THE MILD START TO THE DAY AND ANTICIPATED
BREAK IN THE PRECIP ALONG WITH THICKNESSES NEARLY 20 M ABOVE NORMAL
SHOULD ALLOW TEMPS TO PEAK TODAY IN THE 73-79 RANGE DESPITE PLENTY
OF CLOUDS. WARM LOWS TONIGHT OF 59-65. -GIH
&&
.SHORT TERM / /...
AS OF 345 PM MONDAY...
TO BE UPDATED SHORTLY.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 305 PM MONDAY...
THE MODELS HAVE BEEN FLIP-FLOPPING ON THE SOUTHWARD PENETRATION OF A
COLD FRONT DOWN THE EASTERN SEABOARD INTO THE MID-ATLANTIC STATES
WEDNESDAY INTO THURSDAY. THIS TREND CONTINUED WITH THE 12Z/MODEL
SUITE. THIS HAS FORECAST IMPLICATIONS BOTH DAYS IN TERMS OF MAX
TEMPERATURES/CLOUDS/INSTABILITY/AND CONVECTIVE CHANCES.
SINCE THE CENTER OF THE STRONG SURFACE HIGH PRESSURE IS FORECAST TO
BE A BIT NORTH AND NORTHEAST OF THE FAVORED POSITION FOR DAMMING
DEEP INTO NC/SC PIEDMONT DAMMING REGION... AND WITH THE UPPER RIDGE
FORECAST TO SLOWLY BUILD EASTWARD ACROSS THE SOUTHEASTERN STATES
DURING THE SAME TIME... THE COLD FRONT MAY NOT BE ABLE TO REACH AS
FAR SOUTH AS THE 12Z/OPERATIONAL GFS DEPICTS (INTO NORTHERN SC BY
12Z/THU). HOWEVER... THIS TIME OF YEAR THE WATER TEMPERATURES ARE
STILL COLD NORTH OF CAPE HATTERAS... AND THEY ARE ABNORMALLY COLD
THIS YEAR DUE TO THE COLD WINTER OVER THE NE STATES. WE SUGGEST THAT
THE 12Z/NAM MAY BE THE BEST COMPROMISE GIVEN THE ABOVE DATA... AS
THE 12Z/EC MAY NOT BE FAR ENOUGH SOUTH. THEREFORE... THE MORE
SOUTHWARD PLACEMENT OF THE FRONT IS EXPECTED... WHICH WOULD PLACE
THE COLD FRONT NEAR THE NC/VA BORDER WEDNESDAY AFTERNOON... THEN
DIPPING SOUTHWARD TO NEAR HKY TO FAY TO ILM BY AROUND 12Z/THURSDAY.
THE AIR MASS AND BOUNDARY LAYER OUT AHEAD OF THE FRONT WILL BE
MODESTLY UNSTABLE... ESPECIALLY DURING THE AFTERNOON AND EARLY
EVENING. THE HIGHS ARE FORECAST TO REACH INTO THE UPPER 70S INTO THE
LOWER 80S... WITH DEW POINTS AROUND 60. HOWEVER.. THE COLD FRONT AND
ASSOCIATED LOW LEVEL CONVERGENCE SHOULD ARRIVE IN THE NORTHERN ZONES
DURING THE MID TO LATE AFTERNOON... AND THEN IN THE WESTERN AND
SOUTHERN ZONES IN THE EVENING OR LATER. THUS... THE NAM POP IN THE
HIGH CHANCE RANGE FOR SHOWERS AND THUNDERSTORMS NORTH AND EAST
BETWEEN 18Z-00Z SEEMS THE BEST FIT. THE CHANCE OF SHOWERS AND
THUNDERSTORMS SHOULD PUSH SOUTHWARD WITH THE FRONT INTO THE WESTERN
AND SOUTHERN ZONES WED EVENING.
THE CHANCE OF SHOWERS SHOULD CONTINUE WED NIGHT AND THURSDAY... BUT
CHANCES OF THUNDER APPEAR LOW GIVEN THE EXPECTED INCREASE IN THE
COOLER/STABLE/CLOUDY LOW LEVELS NORTH OF THE FRONT. THE FRONT SHOULD
EITHER BECOME DIFFUSE OR SLIP BACK NORTH AS A WARM FRONT ON THURSDAY
INTO THURSDAY NIGHT... ALLOWING FOR A SLIM CHANCE OF SHOWERS TO
CONTINUE WITH LIMITED UPPER SUPPORT. LOWS GENERALLY IN THE MID 50S
TO NEAR 60 NE... AND LOWER TO MID 60S SOUTH. HIGHS THURSDAY SHOULD
HOLD IN THE 70S (BUT IF FRONT PUSHES BACK NORTH QUICKER THAN
EXPECTED... HIGHS IN THE LOWER TO MID 80S MAY RETURN A DAY SOONER...
ESPECIALLY ACROSS THE SOUTH.
FRIDAY INTO SATURDAY... THE STORM TRACK STILL IS EXPECTED TO OUR
WEST AND NORTH... FINALLY DRAGGING A COLD FRONT INTO AND THROUGH THE
REGION LATE FRIDAY INTO SATURDAY MORNING. A BAND OF SHOWERS AND
SCATTERED THUNDERSTORMS WILL BE POSSIBLE ALONG THE FRONT OR A PRE-
FRONTAL TROUGH (HIGHEST CHANCES LATE FRIDAY INTO EARLY SATURDAY).
FRIDAY SHOULD BE VERY WARM WITH HIGHS IN THE LOWER TO MID 80S.
A TURN TO COOLER AND DRIER CONDITIONS ARE EXPECTED BEHIND THE FRONT
LATER IN THE WEEKEND INTO MONDAY. LOWS IN THE UPPER 40S AND 50S.
HIGHS IN THE 70S SUNDAY AND MONDAY.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 200 AM TUESDAY...
PRIMARY AVIATION CONCERN NEXT 24 HRS: GOOD CHANCE OF CIGS DROPPING
TO MVFR THEN IFR EARLY THIS MORNING... THEN MVFR CIGS ARE EXPECTED
THIS AFTERNOON. POTENTIAL IFR/LIFR CIGS/VSBYS TOWARD THE END OF THE
FORECAST PERIOD (AFTER 03Z TONIGHT).
AVIATION CONDITIONS WILL BECOME MORE UNSETTLED AND ADVERSE THIS
MORNING. A PASSING DISTURBANCE ALOFT EARLY THIS MORNING WILL LEAD TO
A PERIOD OF SHOWERS WITH MVFR VSBYS IN THE FIRST SEVERAL HOURS OF
THE FORECAST... MOVING WEST TO EAST... WITH CIGS LIKELY TO DROP TO
MVFR THEN IFR NEAR OR JUST BEFORE SUNRISE. RECOVERY TO MAINLY MVFR
CIGS IS EXPECTED LATER THIS MORNING... THEN THE NORTHWARD MOVEMENT
OF A WARM FRONTAL ZONE THROUGH THE AREA TODAY WITH ANOTHER
DISTURBANCE WILL BRING ANOTHER CHANCE OF SHOWERS WITH MVFR
VSBYS/CIGS MAINLY DURING THE MID TO LATE AFTERNOON. BY EARLY-MID
EVENING... A PERIOD OF VFR CONDITIONS IS POSSIBLE BEHIND THE
DEPARTING DISTURBANCE... BUT EXPECT DEVELOPMENT OF FOG AND LOW
CLOUDS TOWARD MIDNIGHT... LEADING TO AREAS OF IFR/LIFR CONDITIONS
TOWARD THE END OF THE TAF VALID PERIOD.
LOOKING BEYOND 06Z EARLY WED MORNING: IFR/LIFR CONDITIONS ARE
EXPECTED TO EXTEND UNTIL SUNRISE WED... THEN LIFT TO MVFR BY NOON
AND TO VFR DURING THE EARLY-MID AFTERNOON. HEATING AND INSTABILITY
WILL LEAD TO SCATTERED SHOWERS AND A FEW STORMS WED AFTERNOON WITH
POTENTIAL SUB-VFR CONDITIONS. REDEVELOPMENT OF IFR/LIFR FOG/STRATUS
IS POSSIBLE WED NIGHT INTO THU MORNING. ADDITIONAL SHOWERS/STORMS
THU AFTERNOON MAY BRING BRIEF SUB-VFR CONDITIONS. MORE WIDESPREAD
AND ORGANIZED SHOWERS AND STORMS ARE ANTICIPATED AHEAD OF A COLD
FRONT APPROACHING LATE FRI. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...VINCENT
LONG TERM...BADGETT
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1211 AM CDT TUE APR 7 2015
.UPDATE...
ISSUED AT 1210 AM CDT TUE APR 7 2015
THE LATEST WATER VAPOR IMAGERY AND RADAR SHOWS SEVERAL MOISTURE
PLUMES INCREASING WITH TIME...FROM NORTHWEST THROUGH NORTH
CENTRAL NORTH DAKOTA...AND ACROSS CENTRAL/EASTERN MONTANA SOUTH
INTO WYOMING AND WESTERN SOUTH DAKOTA. LARGE SCALE ASCENT BEING
MAXIMIZED IN EASTTERN MONTANA AND AREAS SOUTH...AHEAD OF A
NEGATIVELY TILTED 700MB-500MB SHORTWAVE TROUGH LOCATED IN NORTH
CENTRAL MONTANA. BOWMAN RADAR NOW SHOWING INCREASING REFLECTIVITY`S
UPSTREAM...WHICH COINCIDES WITH THE CURRENT FORECAST OVERNIGHT AS
PRECIPITATION CHANCES INCREASE. STRONGEST LIFT PER OMEGA FIELD
OCCURS FROM NEAR 12Z TUESDAY WEST...TRANSLATING EAST THROUGH 18Z.
CATEGORICAL POPS CURRENTLY IN THE FORECAST LOOKS GOOD. WITH
OVERALL POPS ON TRACK...NO CHANGES WITH THIS FORECAST UPDATE.
UPDATE ISSUED AT 842 PM CDT MON APR 6 2015
ISENTROPIC LIFT GENERALLY LACKING ON THE 285K SURFACE OVER
SOUTHWEST AND SOUTHERN NORTH DAKOTA THIS EVENING. MAIN ACTION
FOR SNOW CONTINUES TO BE NORTHWEST INTO THE WEST CENTRAL SECTIONS
OF NORTH DAKOTA. FOR THE REST OF THE EVENING WILL DROP POPS BELOW
15 PERCENT ACROSS THE SOUTHERN THIRD OF THE STATE. WILL THEN
SLOWLY SPREAD CHANCE POPS BACK IN AFTER MIDNIGHT SOUTH. WILL ALSO
TRIM QPF SOUTH AS WELL. THE NORTH LOOKS GOOD.
UPDATE ISSUED AT 618 PM CDT MON APR 6 2015
LATEST HRRR SEEMS TO HAVE A REASONABLE HANDLE ON THE TRENDS EARLY
THIS EVENING AND FOLLOWED FOR THE NEXT 6 HOURS OR SO. BAND OF
PRECIPITATION SEEN ON RADAR EXTENDING FROM BISMARCK NORTHWEST TO
BEACH IS MOVING NORTH AND WILL SPREAD ACROSS NORTHWEST ND WHERE
CURRENT HIGH POPS ARE IN GOOD SHAPE. THIS LEAVES THE SOUTHERN
THIRD OF THE STATE WITH LITTLE IN THE WAY OF PRECIPITATION. SO
TRIMMED THE POPS BACK TO SLIGHT CHANCE ACROSS THE SOUTH FOR THE
EVENING. FOCUSED ON THE WEST CENTRAL AND NORTHWEST WHERE BEST
PRECIPITATION WILL BE WIDESPREAD THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 300 PM CDT MON APR 6 2015
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE RAIN AND
SNOW CHANCES AND AMOUNTS NOW THROUGH TUESDAY.
CURRENTLY...THE FIRST IN A SERIES OF MID LEVEL S/WV`S APPROACHING
THE NORTHERN PLAINS THIS AFTERNOON. IN RESPONSE PRECIPITATION
DEVELOPMENT UNDERWAY SOUTHWEST WITH BEACH AND DICKINSON NOW
REPORTING SNOW THE PAST HOUR. VERY DRY AIR ACROSS EASTERN NORTH
DAKOTA WILL PREVENT ANYTHING FROM REACHING THE GROUND THIS
AFTERNOON.
PRECIPITATION WILL CONTINUE TO EXPAND NORTH AND EAST AS THE
AFOREMENTIONED WAVE CONTINUES NORTHEAST AND ONCE A STRONGER/MORE
INTENSE WAVE LIFTS INTO THE REGION TONIGHT. IN ADDITION...LOW/MID
LEVEL WINDS WILL BECOME MORE SOUTHEAST TONIGHT VERSUS
EASTERLY...ALLOWING FOR MOISTURE ADVECTION INTO THE REGION HELPING
TO ERODE A VERY DRY BOUNDARY LAYER NOW IN PLACE. SHOULD SEE A
TRANSITION TO ALL SNOW AFTER 00Z AS TEMPERATURES COOL. WILL
CONTINUE THE SPECIAL WEATHER STATEMENT HIGHLIGHTING 3 TO 5 INCHES
OF SNOW FOR PORTIONS OF THE WEST/NORTHWEST/NORTH CENTRAL DURING
THE NEXT 36 HOURS. LESSER AMOUNTS STILL EXPECTED SOUTHWEST AND
SOUTH CENTRAL WHERE A RAIN/SNOW MIX OR ALL RAIN WILL MINIMIZE
ACCUMULATIONS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 300 PM CDT MON APR 6 2015
THE FOCUS OF THE LONG TERM FORECAST IS THE CHANCE FOR RAIN/SNOW
WEDNESDAY.
LATEST 12 UTC GUIDANCE (WITH THE EXCEPTION OF THE NAM) ARE IN GOOD
AGREEMENT WITH RESPECT TO THE TIMING AND LOCATION OF PRECIPITATION
WEDNESDAY. SNOW IS EXPECTED TO MIX WITH RAIN ACROSS SOUTHWESTERN
NORTH DAKOTA WEDNESDAY MORNING AS A RATHER LARGE AND DEEP LOW
PRESSURE CENTER MOVES ACROSS THE CENTRAL PLAINS. DURING THE DAY
ON WEDNESDAY TEMPERATURES SHOULD BE WARM ENOUGH TO CHANGE SNOW
OVER TO ALL RAIN AND MELT ANY PREVIOUSLY ACCUMULATED SNOW ACROSS
SOUTHERN NORTH DAKOTA. THE MAJORITY OF THE PRECIPITATION AS
DEPICTED IN THE 12 UTC GFS/ECMWF/SREF APPEARS MOST LIKELY TO FALL
ALONG AND SOUTH OF INTERSTATE 94. AS COLDER AIR WRAPS AROUND THE
DEPARTING LOW AND DIURNAL COOLING BEGINS...RAIN MAY TRANSITION
BACK OVER TO SNOW WEDNESDAY NIGHT INTO THURSDAY MORNING.
HOWEVER...ONLY MINOR AMOUNTS ARE ANTICIPATED TO ACCUMULATE AS
GROUND TEMPERATURES SHOULD HOVER RIGHT AROUND FREEZING OVERNIGHT.
THE REST OF THE EXTENDED LOOKS RATHER DRY AND MILD WITH
TEMPERATURES IN THE 60S BY THE WEEKEND. PRECIPITATION MAY RETURN TO
THE REGION BY THE END OF THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1210 AM CDT TUE APR 7 2015
CIGS/VSBYS WILL QUICKLY DETERIORATE TO MVFR/IFR STATUS BY 12Z
TUESDAY AS LIGHT SNOW CONTINUES TO DEVELOP ACROSS THE TERMINALS.
PRECIPITATION WILL BECOME WIDESPREAD FROM 12Z THROUGH 18Z TUESDAY.
EXPECT PRECIPITATION TO WANE FROM SOUTHWEST TO NORTHEAST 18Z TUESDAY
TO 00Z WEDNESDAY. ALTHOUGH VSBYS RETURN TO VFR EARLY TUESDAY
AFTERNOON...SLOWER IMPROVEMENTS CAN BE EXPECTED IN THE
CIGS...LIFTING TO MVFR AND POSSIBLY LOW VFR BETWEEN 00Z AND 06Z
WEDNESDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...NH
LONG TERM...AJ
AVIATION...KS
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
1153 PM CDT MON APR 6 2015
.AVIATION...07/06Z TAF ISSUANCE...
CEILINGS AND VISIBILITY REMAIN A CHALLENGE FOR SITES ACROSS SWRN
AND POSSIBLY CENTRAL OK THIS MORNING. LATEST SHORT RANGE GUIDANCE
SUGGEST VFR CONDITIONS WILL PREVAIL AND GIVEN CURRENT
CONDITIONS... THIS SOLUTION SEEMS LIKELY. HOWEVER... THERE MAY BE
A CHANCE OF LIGHT FOG... BUT MORE LIKELY LOW STRATUS CLOUDS ACROSS
A NARROW CORRIDOR OF WRN OK WHERE WINDS RELAX SLIGHTLY AND
TEMP/DEW POINT SPREADS LESSEN NEAR DAY BREAK. OVERALL... EXPECT
VFR CONDITIONS TO PREVAIL THROUGH THE PERIOD AT THIS TIME... BUT
FEEL COMPELLED TO PUT IN A TEMPO FOR LIGHT 4SM BR AND MVFR CIGS AT
KCSM/KHBR AROUND SUNRISE. SOUTH WINDS WILL REMAIN BREEZY
OVERNIGHT... INCREASING TOMORROW LATE MORNING/AFTERNOON AS THE
PRESSURE GRADIENT INCREASES AND A DRY LINE PUSHES EASTWARD INTO
WRN OK/WRN N TX. GUSTS ACROSS WRN INTO CENTRAL OK COULD APPROACH
20 TO 25 KTS THROUGH THE AFTN.
JTK
&&
.PREV DISCUSSION... /ISSUED 714 PM CDT MON APR 6 2015/
UPDATE...
UPDATE TEMPS... WEATHER...
DISCUSSION...
ADJUSTED ISOLATED THUNDER TO A MORE CONFINED AREA OF CENTRAL TO
SWRN OK TO WRN N TX IN ACCORDANCE WITH THE SIGNIFICANT CLOUD COVER
AND SPORADIC CUMULUS THAT HAS DEVELOPED ALONG THE DRY LINE SWRN
OK. THE CHANCE FOR A FEW ISOLATED STORMS CANNOT BE RULED OUT
THROUGH SUNSET... BUT THE CHANCE REMAINS VERY LOW.
ADJUSTED TEMPS... BRINING THEM BACK IN LINE WITH OBS TREND AS
CURRENT FORECAST WAS RUNNING A TAD COOLER ACROSS WRN OK...
CONSIDERING THERE IS STILL UPPER 80S AND LOWER 90S IN THE TX
PANHANDLE.
JTK
PREV DISCUSSION... /ISSUED 336 PM CDT MON APR 6 2015/
DISCUSSION...
CONVECTION...
THE HRRR AND RAP HAVE SHOWN A RELATIVELY CONSISTENT SIGNAL OF
ISOLATED STORM/S/ DEVELOPING IN THE SOUTHWEST LATE THIS AFTERNOON.
MESOANALYSIS SHOW CONVECTIVE INHIBITION DECEASING ACROSS NORTHWEST
TEXAS. IT IS NOT A SURE THING THAT ANY STORM WILL DEVELOP AND
COVERAGE WILL BE LIMITED IF STORMS DO DEVELOP. BUT THERMODYNAMIC
PROFILE SHOWS QUITE AN UNSTABLE ATMOSPHERE... SO SEVERE WEATHER
WOULD BE LIKELY IF A STORM DOES INDEED DEVELOP. WILL KEEP POPS
BELOW 20 BUT ADD ISOLATED THUNDER IN THE WEATHER GRIDS IN TO COVER
THE POTENTIAL DEVELOPMENT. MUCH THE SAME SCENARIO IS EXPECTED
TOMORROW WITH AN UNSTABLE BUT GENERALLY CAPPED ATMOSPHERE WITHOUT
SIGNIFICANT FORCING... BUT CONVECTIVE INHIBITION DECREASES ENOUGH
THAT ISOLATED STORMS ARE POSSIBLE AGAIN IN THE LATE AFTERNOON AND
EARLY EVENING.
WEDNESDAY STILL LOOKS TO HAVE A MORE SIGNIFICANT SEVERE WEATHER
POTENTIAL AS THE TROUGH THAT IS CURRENTLY LOCATED OFF THE PACIFIC
COAST MOVES TOWARD THE HIGH PLAINS. WE EXPECT STORMS TO DEVELOP
WEDNESDAY AFTERNOON OR EVENING NEAR THE DRYLINE AND SPREAD EAST
WITH A DECENT CHANCE OF SEVERE WEATHER. THE STORM CHANCES WILL
LINGER INTO THURSDAY IN THE SOUTHEAST UNTIL THE SURFACE FRONT
MOVES THROUGH.
AFTER A BRIEF RESPITE FRIDAY...ANOTHER UPPER TROUGH APPROACHES
THIS WEEKEND INCREASING STORM CHANCES AGAIN THIS WEEKEND. EVEN AS
THE FIRST TROUGH MOVES BY THE PLAINS... THE MEAN TROUGH WILL
PERSIST IN THE WEST ALLOWING CONTINUED STORM CHANCES THROUGH
MONDAY.
FIRE WEATHER...
GUSTY POST-DRYLINE WINDS HAVE SPREAD INTO NORTHWESTERN OKLAHOMA
ALONG WITH TEMPERATURES IN THE LOWER 90S AND HUMIDITY IN THE
SINGLE DIGITS AND TEENS.... SO THE CURRENT RED FLAG WARNING LOOKS
GOOD INTO THE EARLY EVENING. ALTHOUGH WE WILL HAVE THE HEAT AND
LOW HUMIDITY AGAIN TOMORROW... WINDS ARE EXPECTED TO BE LIGHTER.
WINDS LOOK HIGHER AGAIN ON WEDNESDAY SO THE FIRE WEATHER WATCH IS
STILL VALID.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 65 84 66 82 / 10 20 20 30
HOBART OK 60 87 64 86 / 10 10 10 20
WICHITA FALLS TX 66 87 66 88 / 10 20 10 30
GAGE OK 53 88 53 85 / 10 0 10 10
PONCA CITY OK 63 87 64 85 / 10 20 20 40
DURANT OK 68 80 68 81 / 10 10 10 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR OKZ004>006-009>011-014>016-021-022-033>037.
TX...FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR TXZ083>085-087-088.
&&
$$
99/99/01
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1227 AM CDT TUE APR 7 2015
.AVIATION...
MVFR CIGS HAVE DEVELOPED/SPREAD OVER MUCH OF SOUTH CENTRAL
TEXAS...MOSTLY ALONG THE BALCONES ESCARPMENT AND IN THE HILL
COUNTRY. EXPECT COVERAGE TO EXPAND ACROSS THE EASTERN COASTAL
PLAINS AND WESTERN RIO GRANDE PLAINS OVERNIGHT...AS WELL AS A
LOWERING TO IFR CIGS AT MOST LOCATIONS AFTER 10Z. IFR CIGS WITH
4-6SM BR VSBYS WILL PREVAIL THROUGH 16-17Z TUESDAY. AFTER
THAT...THE FOG SHOULD DISSIPATE QUICKLY AND CIGS LIFT INTO MVFR
AND BEGIN TO THIN...BUT WINDS WILL INCREASE TO 10G20KT OR SLIGHTLY
HIGHER. LOOK FOR VFR SKIES AFTER 19Z...BUT MVFR CIGS WILL RETURN
AROUND 02-04Z...THEN LOWER TO IFR CIGS FOR THE EXTENDED TAFS AT
KAUS AND KSAT.
&&
.PREV DISCUSSION... /ISSUED 934 PM CDT MON APR 6 2015/
UPDATE...
LATE AFTERNOON/EARLY EVENING STORMS OUT OF THE NORTHEAST MEXICAN
MOUNTAINS DISSIPATED AS THEY WERE MOVING EAST AND INTO A CAPPED
REGION. MOST OF THE HIRES AND MEDIUM RANGE GUIDANCE ARE KEEPING
THE AREA DRY OVERNIGHT WITH THE EXCEPTION OF LATEST HRRR AND RAPIP
REFRESH WHICH BRING ISOLATED STORMS ACROSS THE RIO GRANDE PLAINS
OVERNIGHT. AT THIS TIME...WILL GO WITH A DRY FORECAST AFTER
MIDNIGHT AS SUGGESTED BY THE MAJORITY OF THE MODEL SOLUTIONS.
ALSO...ADJUSTED TONIGHT`S TEMPS BASED ON CURRENT TRENDS AND MAV
GUIDANCE.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 83 68 84 69 84 / 10 10 10 10 10
AUSTIN BERGSTROM INTL AIRPORT 82 67 83 68 83 / 10 10 10 10 10
NEW BRAUNFELS MUNI AIRPORT 83 67 85 67 85 / 10 10 10 10 10
BURNET MUNI AIRPORT 82 67 84 66 83 / 10 10 10 10 10
DEL RIO INTL AIRPORT 84 69 87 69 88 / 10 20 10 10 10
GEORGETOWN MUNI AIRPORT 82 68 83 68 83 / 10 10 10 10 10
HONDO MUNI AIRPORT 82 68 84 68 86 / 10 10 10 - 10
SAN MARCOS MUNI AIRPORT 82 67 84 68 83 / 10 10 10 10 10
LA GRANGE - FAYETTE REGIONAL 82 69 84 70 83 / 10 10 10 10 10
SAN ANTONIO INTL AIRPORT 83 68 84 69 84 / 10 10 10 10 10
STINSON MUNI AIRPORT 83 68 84 68 85 / 10 10 10 10 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...26
SYNOPTIC/GRIDS...04
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1139 PM CDT MON APR 6 2015
.DISCUSSION...
SEE 06Z AVIATION DISCUSSION.
&&
.AVIATION...
MODELS ARE AGAIN VERY AGGRESSIVE AND TOO QUICK WITH LOWERING CIGS
INTO IFR/MVFR. THE HRRR/NAM AND RAP ARE TOO LOW WITH CIGS AND
INITIALIZED POORLY. PREFER THE GFS FOR THE OVERNIGHT HOURS AND
EVEN THE GFS EVENTUALLY LOWERS CIGS TO UNDER A 1000 FEET BY 12Z
TUES. THERE SHOULD BE A BRIEF WINDOW OF LIFR/IFR CONDS AT ALL TAF
SITES BETWEEN 11-15Z. THE GFS ALSO SCATTERS CLOUDS OUT BY 18Z
WHICH MIGHT BE A TAD FAST. MVFR CIGS EXPECTED TO REDEVELOP LATE
TUESDAY NIGHT. LIGHT TO MODERATE S-SE WINDS ARE EXPECTED THROUGH
THE TAF PERIOD.
&&
.PREV DISCUSSION... /ISSUED 1015 PM CDT MON APR 6 2015/
UPDATE...
A FEW LIGHT RETURNS SHOWING UP EAST OF THE AREA THIS EVENING
AHEAD OF A DISTURBANCE CROSSING TEXAS FROM MEXICO MAY PRODUCE A
SPRINKLE OR TWO OVER THE FAR NORTHWESTERN FORECAST AREA...
BUT EXPECT TONIGHT TO BE MOSTLY DRY ACROSS THE FORECAST AREA WITH
A RATHER STOUT LAYER OF LOW TO MID LEVEL DRY AIR IN PLACE AND
AIRCRAFT SOUNDINGS OUT OF HOUSTON SHOWING A CAPPING INVERSION
BETWEEN 800-700 MB.
FOR THIS UPDATE... ONLY MINOR ADJUSTMENTS MADE TO TEMPERATURE AND
DEW POINT GRIDS BASED ON LATEST OBSERVATIONS.
HUFFMAN
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 67 82 68 82 70 / 10 10 10 10 20
HOUSTON (IAH) 68 84 69 83 70 / 10 10 10 10 10
GALVESTON (GLS) 69 77 71 78 71 / 10 10 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1200 AM CDT TUE APR 7 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 337 PM CDT MON APR 6 2015
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED BROAD UPPER TROUGHING ALONG THE WEST COAST OF THE
U.S....RIDGING ACROSS THE PLAINS AND THEN ZONAL FLOW ACROSS THE
GREAT LAKES AND NEW ENGLAND. A STATIONARY SURFACE FRONTAL ZONE
EXISTS UNDERNEATH THE RIDGING AND ZONAL FLOW NEAR I-80...WITH A MID
LEVEL FRONTOGENESIS AXIS WELL TO THE NORTH ACROSS CENTRAL MN AND
NORTHERN WI. SOME PRECIPITATION WAS FALLING OUT OF THIS AXIS...BUT
A NORTHEAST FLOW OF CANADIAN DRY AIR FROM HIGH PRESSURE IN ONTARIO
HAS DIMINISHED MUCH OF THE PRECIPITATION. THE 12Z GRB SOUNDING AND
ESPECIALLY THE INL SOUNDING SHOWED THAT DRY AIR NICELY. SOME OF THAT
DRY AIR INFILTRATED INTO THE FORECAST AREA THIS MORNING TO CLEAR
SKIES OUT FROM THE STRATUS. HOWEVER...MID AND HIGH CLOUDS WERE
SPREADING BACK OVER THE AREA FROM A BROAD WARM ADVECTION REGIME
UNDER THE UPPER RIDGE...AND THEN SOME LOW STRATUS WAS TRYING TO BACK
INTO THE AREA FROM NORTHEAST WI. A FEW SHOWERS AND STORMS HAVE BEEN
GOING ON NEAR WATERLOO IA MARCHING EAST-NORTHEAST...ASSOCIATED WITH
A WEAK SHORTWAVE INTERACTING WITH THE WARM/MOIST ADVECTION. QUITE
THE LOW LEVEL THERMAL TEMPERATURE GRADIENT EXITS ACROSS THE FORECAST
AREA. PER RAP 925MB TEMPS... READINGS NORTH OF HIGHWAY 29 ARE AROUND
0C COMPARED TO 8C OVER NORTHERN IA AND SOUTHERN WI. FARTHER
SOUTHWEST 20C PLUS 925MB READINGS EXISTS IN WESTERN KS.
THE UPPER RIDGING OVER THE PLAINS IS PROGGED TO PROGRESS OVER THE
FORECAST AREA OVER THE NEXT 24 HOURS IN RESPONSE TO THE TROUGH ALONG
THE WEST COAST MOVING INLAND SLIGHTLY. THIS WILL PUT THE FORECAST
AREA IN A WARM/MOISTURE ADVECTION ZONE ALOFT. ISENTROPIC LIFT FIELDS
SHOW THIS NICELY...ESPECIALLY DURING THE DAY TUESDAY AND EVEN MORESO
IN THE AFTERNOON WEST OF THE MS RIVER ON 290-300K SURFACES.
THUS...WE SHOULD SEE A CONTINUOUS INCREASE AND THICKENING OF CLOUD
COVER. AN EAST TO NORTHEAST LOW LEVEL FLOW BRINGING IN DRIER AIR
FROM ONTARIO WILL HAMPER SOME OF THE PRECIPITATION PRODUCTION...OR
MAKE IT SPOTTY...UNTIL TUESDAY AFTERNOON WHEN PRECIPITABLE WATER
SURGES UP TO 0.75 TO 1 INCH. THEREFORE HIGHEST PRECIPITATION CHANCES
ARE PLACED IN THE LATE TUE AFTERNOON TIME PERIOD.
THE INCREASE IN CLOUD COVER WOULD HELP TO KEEP TEMPERATURES UP.
HOWEVER...THE EASTERLY FLOW OF COOLER DRY AIR IN CONJUNCTION WITH
SPOTTY PRECIPITATION WILL WORK TOGETHER TO KNOCK TEMPERATURES DOWN.
AS SUCH...925MB TEMPS FALL TO -2C NORTH TO +4C SOUTH BY 12Z TUE AND
LINGER NEAR THERE THROUGH MUCH OF TUESDAY. READINGS MAY STRUGGLE TO
CLIMB MUCH ON TUESDAY WITH LIMITED SUNSHINE...AND THE MORE
WIDESPREAD LATE AFTERNOON RAIN NOT HELPING MATTERS.
THE AFOREMENTIONED TEMPERATURES BRING ABOUT PRECIPITATION TYPE
CONCERNS ACROSS TAYLOR/CLARK COUNTY WHERE THE COLDEST AIR EXISTS.
SURFACE TEMPERATURES LOOK TO FALL BACK BELOW FREEZING TONIGHT. FOR
THE EVENING ICE IS SUGGESTED IN THE CLOUDS...SO THERE COULD BE A
RAIN/SNOW MIX. THEN DURING THE OVERNIGHT AND MUCH OF TUESDAY
MORNING...THE ICE IN THE CLOUDS DEPARTS TO THE NORTHEAST...LEAVING
THE POTENTIAL FOR FREEZING RAIN WITH ANY PRECIPITATION.
HOWEVER...ITS POSSIBLE THAT THE LOSS OF ICE MAY END UP ENDING THE
PRECIPITATION ENTIRELY AS SUGGESTED BY THE 06.12Z GFS.
THEREFORE...HAVE NOT ISSUED ANY WINTER WEATHER OR FREEZING RAIN
ADVISORY AT THIS TIME.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 337 PM CDT MON APR 6 2015
THERE ARE TWO MAIN PERIODS OF WEATHER FOCUS...TUESDAY NIGHT AND
LATE WEDNESDAY INTO THURSDAY NIGHT.
A SHORTWAVE TROUGH IS PROGGED TO CROSS MINNESOTA AND WISCONSIN
TUESDAY NIGHT...BRINGING WITH IT A DECENT SURGE OF 850MB MOISTURE
TRANSPORT / ISENTROPIC LIFT. MOISTURE SHOULD BE PLENTIFUL WITH
PRECIPITABLE WATER OF 0.75-1 INCH AND SATURATED SOUNDINGS. THEREFORE
CONDITIONS LOOK FAVORABLE FOR RAIN AND RAISED CHANCES UP TO 80. BEST
JUXTAPOSITION OF LIFT IS SITUATED SOUTH OF I-90 DURING THE EVENING.
ADDITIONALLY...WITH MUCAPE VALUES IN 200-500 J/KG RANGE DURING THE
EVENING ROOTED ABOVE 850MB AND LITTLE CAP...EXPECTING AT LEAST
ISOLATED THUNDERSTORMS TO OCCUR. PRECIPITATION SHOULD DIMINISH WEST
TO EAST AFTER MIDNIGHT AS THE LIFT MOVES OFF TO THE EAST AND
SUBSIDENCE COMES IN. PRECIPITATION TYPE FOR THE MOST PART LOOKS TO
BE RAIN WITH PLENTY OF WARM AIR IN PLACE...EXCEPT FOR TAYLOR COUNTY
SHOULD THE PRECIPITATION GET UP THERE. IN TAYLOR COUNTY...THE AIR
MAY BE COLD ENOUGH TO ALLOW FOR SLEET OR FREEZING RAIN.
A BRIEF BREAK LOOKS TO OCCUR FOR MUCH OF THE DAY WEDNESDAY...UNTIL
THE LATER AFTERNOON HOURS. THIS IS WHEN THE TROUGHING ALONG THE U.S.
WEST COAST BEGINS THE MARCH TOWARDS THE PLAINS...PUSHING ANOTHER
SURGE OF 850MB MOISTURE TRANSPORT AND ISENTROPIC LIFT INTO THE
FORECAST AREA. PRECIPITABLE WATER ALSO CLIMBS BACK TO 0.75-1 INCH
AFTER FALLING TO NEAR 0.5 INCH DURING THE MORNING. THE SURGE OF
MOISTURE TRANSPORT IS MORE IMPRESSIVE FOR WEDNESDAY NIGHT COMPARED
TO TUESDAY NIGHT...AND IT APPEARS EVERYWHERE SHOULD PICK OF
PRECIPITATION. ANTICIPATING RAIN TO BE THE MAIN PRECIPITATION TYPE
WITH ANY MIXED PRECIPITATION STAYING JUST NORTH OF THE FORECAST
AREA. SHOULD SEE SOME THUNDERSTORMS AGAIN SOUTH OF I-90 AS MUCAPE
ABOVE ANY ELEVATED CAPPING INCREASES TO 200-500 J/KG.
AS WE HEAD INTO THURSDAY...MODELS BEGIN TO SPREAD OUT ON THE SPEED
AND STRENGTH OF THE UPPER TROUGH...IMPACTING THE TRACK OF THE
SURFACE SYSTEM AND WARM SECTOR. THE ECMWF HAS BEEN HOLDING FAIRLY
STEADY WITH A MORE POSITIVE TILT TROUGH AND FARTHER SOUTHEAST
SURFACE LOW. ON THE OTHER HAND...THE 06.12Z GFS/CANADIAN/NAM ARE
MORE NEUTRAL AND EVEN NEGATIVE TILT IN THE NAM...RESULTING IN A
STRONGER SURFACE LOW. HARD TO SAY WHAT SCENARIO WILL PAN OUT...BUT
WITH THE ECMWF ENSEMBLE MEAN SIMILAR TO THE ECMWF...FEEL THE ECMWF
MAY BE MORE LIKELY TO WORK OUT. IN ANY EVENT...PRECIPITATION LOOKS
LIKE A GOOD BET TO CONTINUE ON THURSDAY...BUT OF A LIGHTER VARIETY
AS THE FORCING DIMINISHES TO JUST THE DPVA FROM THE UPPER TROUGH.
TYPE LOOKS TO HOLD AS RAIN. AGAIN THUNDERSTORMS ARE POSSIBLE SOUTH
OF I-90...AND IF THE FARTHER NORTHWEST 06.12Z CANADIAN/GFS PAN OUT
COULD EVEN SEE A SEVERE RISK IN FAR NORTHEAST IA/SOUTHWEST WI.
SOMETHING TO MONITOR. TEMPERATURES EXTREMELY TRICKY FOR THURSDAY AS
THEY DEPEND ON THE LOW TRACK. FOLLOWED A MODEL CONSENSUS FOR NOW.
THURSDAY NIGHT IS DOMINATED BY A COLD CONVEYOR BELT IMPACTING THE
NORTHWEST HALF OF THE FORECAST AREA...WHILE A DRY SLOT ACCOMPANYING
THE UPPER TROUGH TRIES TO MOVE THROUGH THE SOUTHEAST HALF. UNDER THE
COLD CONVEYOR BELT COULD SEE PRECIPITATION MIX WITH OR CHANGE OVER
TO SNOW...ESPECIALLY AS THE NIGHT WEARS ON AS TEMPERATURES COOL.
HOWEVER...BY THE TIME PRECIPITATION BEGINS TO SWITCH OVER...IT COULD
ALSO BE ENDING. THUS...NO SNOW ACCUMULATION IS ANTICIPATED AT THIS
TIME.
STILL KEPT SOME PRECIPITATION CHANCES IN FOR FRIDAY BASED ON A MODEL
CONSENSUS BUT NEW 06.12Z ECMWF/GFS WOULD SUGGEST A DRIER FORECAST
AND OUR FORECAST MAY BE ABLE TO BE DRIED OUT. ALTHOUGH COOL AIR
COMES IN BEHIND THE UPPER TROUGH FOR FRIDAY...POTENTIAL EXISTS FOR
MORE SUN COMPARED TO THURSDAY AND THUS HIGHS FOR MANY LOCATIONS END
UP SIMILAR.
FOR THE WEEKEND INTO EARLY NEXT WEEK. GOOD MODEL AGREEMENT EXISTS
AMONGST THE 06.12Z GFS/ECMWF/CANADIAN FOR UPPER RIDGING TO BUILD
INTO THE AREA FRIDAY NIGHT AND SATURDAY...RESULTING IN DRY
CONDITIONS. FRIDAY NIGHT COULD BE ON THE COOL SIDE WITH SURFACE HIGH
IN PLACE AND CLEARING. MAY EVEN END UP WITH SOME RADIATION FOG.
TEMPERATURES SHOULD REBOUND NICELY ON SATURDAY WITH SUN. THEN ON
SUNDAY AND MONDAY ANOTHER TROUGH THAT FORMS OVER THE WESTERN U.S.
LIFTS INTO/AFFECTS THE REGION. AS A RESULT PRECIPITATION CHANCES
RETURN. TYPE FOR THE MOST PART SHOULD BE RAIN. WARM ADVECTION HELPS
TO PUSH TEMPERATURES TO NEAR OR SLIGHTLY ABOVE SEASONABLE NORMALS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1155 PM CDT MON APR 6 2015
KEPT TREND OF LOWERING CEILINGS TONIGHT AND OBSERVATIONS SEEM TO
SUPPORT THIS WITH SCT015 SHOWING UP NOW IN WI JUST EAST OF KLSE.
THIS WILL PROGRESS WEST TONIGHT AND BE COMMON BY SUNRISE. WINDS
FROM THE EAST WILL BE GUSTY TUESDAY AND A STRONG WEATHER SYSTEM
MOVES INTO IOWA. SOME INSTABILITY WILL BE PRESENT NEAR THE TAF
SITES BY LATE TUESDAY AS STRONG LIFT COMES INTO THE AREA...WITH
RAIN EXPECTED. DID NOT INCLUDE THUNDER AT THE TAF SITES YET...BUT
FUTURE FORECASTS WILL HAVE TO ASSESS THIS FOR 22Z+ TUESDAY.
ALSO...SOME DRIZZLE MAY BE AROUND THE TAF SITES AFTER 18Z
TUESDAY...BUT DO NOT BELIEVE IT WILL BE A FACTOR TO AVIATION.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BAUMGARDT
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
333 AM MDT TUE APR 7 2015
.SHORT TERM...(TODAY THROUGH THURSDAY NIGHT)
ISSUED AT 159 AM MDT TUE APR 7 2015
IF YOU ARE AN AFICIONADO OF THE GAMUT OF WEATHER PHENOMENON...YOU
WILL LOVE THE NEXT FEW DAYS.
TODAY...AS EXPECTED BY OUR FORECAST TEAM...LOW CLOUDS AND FOG HAVE
DEVELOPED ALONG AND EAST OF THE LARAMIE RANGE AND INTERSTATE 25
CORRIDOR WITH MOIST LOW LEVEL UPSLOPE. HAVE FOLLOWED THE CURRENT
AREAL FOG COVERAGE AND BOUNDARY LAYER PROGS FOR PAINTING FOG AREAS
THIS MORNING.
FOR THIS AFTERNOON...ATTENTION THEN SHIFTS TO AREAL COVERAGE OF
SHOWERS AND THUNDERSTORMS. DECENT SOUTHWEST FLOW ALOFT WITH WEAK
SHORTWAVE TROUGH MOVING NORTHEASTWARD OVER OUR COUNTIES NEAR PEAK
HEATING...WITH LOW LEVEL EAST SOUTHEASTERLIES ADVECTING LOW LEVEL
MOISTURE TO THE BASE OF THE LARAMIE RANGE. BASED ON THE LOCATIONS OF
THE 850 MB AND 700 MB THETA-E RIDGES...FROM DOUGLAS TO CHEYENNE TO
SIDNEY AND UPWARD VERTICAL MOTION...EXPECT ISOLATED TO SCATTERED
AFTERNOON SHOWERS ALONG THIS THETA-E RIDGE...MOST NUMEROUS FROM
DOUGLAS TO WHEATLAND WHERE UVV AND THETA-E RIDGING IS MOST
COINCIDENT. ENOUGH INSTABILITY FOR A FEW THUNDERSTORMS AS WELL.
TONIGHT...FLOW ALOFT BACKS IN ADVANCE OF THE APPROACHING STRONGER
SHORTWAVE TROUGH...WITH MOIST LOW LEVEL UPSLOPE SOUTHEAST WINDS
CONTINUING TO ADVECT MOISTURE ACROSS OUR EASTERN PLAINS ALONG AND
EAST OF INTERSTATE 25. WILL SEE AN INCREASE IN AREAL COVERAGE OF FOG
ALONG AND EAST OF INTERSTATE 25...AND MAY EVEN SEE SOME AREAS OF
DENSE FOG DEPENDING ON THE AREAL COVERAGE OF LOW CLOUDS AND IF
ISOLATED SHOWERS ARE MINIMIZED.
WEDNESDAY...WOULD NOT BE SURPRISED TO SEE OUR TEAM ISSUE OUR FIRST
SEVERE THUNDERSTORM WARNING OF THE SEASON IN THE AFTERNOON OR
EVENING. IMPRESSIVE AND ROBUST SHORTWAVE TROUGH ALOFT MOVES OVER
CENTRAL WYOMING IN THE AFTERNOON...WITH AN IMPRESSIVE INVERTED
SURFACE TROUGH AXIS ACROSS OUR FAR EASTERN WYOMING COUNTIES. QUITE
PRONOUNCED 850 MB THETA-E RIDGE AXIS EXTENDS ALONG AND JUST WEST OF
THE WYOMING AND NEBRASKA STATE LINE IN THE AFTERNOON...WITH ROARING
LEFT FRONT QUADRANT OF THE 300 MB JET STREAKING IN FROM SOUTHWEST TO
NORTHEAST. ALTHOUGH CAPE WILL NOT BE OVERLY IMPRESSIVE...WITH
PROGGED 500-300 MB AND 700-500 MB QUASIGEOSTROPHIC LIFT...TIMING
COINCIDENT WITH PEAK HEATING...AND SHEAR...WE EXPECT SCATTERED
AFTERNOON THUNDERSTORMS EAST OF INTERSTATE 25...WITH A FEW STORMS
BECOMING STRONG TO SEVERE FROM LATE AFTERNOON THROUGH EARLY
EVENING AND THE BEST THREAT FOR STRONGEST THUNDERSTORMS FROM LUSK
TO TORRINGTON TO PINE BLUFFS IN THE AFTERNOON...THEN INTO THE
PANHANDLE IN THE EVENING. WIDESPREAD SHOWERS FOCUSED ALONG THE
INSTABILITY AXIS IN THE AFTERNOON EAST OF INTERSTATE 25.
WEDNESDAY NIGHT...WITH PLENTY OF LOW AND MID LEVEL MOISTURE AS
FUEL...AND THE ENERGIZED PROGRESSIVE SHORTWAVE TROUGH ALOFT MOVING
OVERHEAD...ALONG WITH A POTENT PACIFIC ORIGIN COLD FRONT PASSAGE AND
BAROCLINIC BAND...WILL SEE WIDESPREAD SHOWERS EAST OF I-25 WITH
LESSER COVERAGE WEST OF I-25. PRECIPITATION WILL SWITCH OVER TO SNOW
WITH MINIMAL ACCUMULATIONS AT LOWER ELEVATIONS...THOUGH WE MAY SEE
2 TO 5 INCHES OF SNOW OVER THE SNOWY RANGE AND SIERRA MADRES AND
NORTHERN LARAMIE RANGE. WILL SEE AREAS OF FOG DEVELOP...THOUGH
MINIMIZED BY THE WIDESPREAD SNOW SHOWERS AFTER MIDNIGHT. WINDY AND
CHILLY. TOTAL SNOWFALL OF 3 TO 7 INCHES EXPECTED BY FRIDAY MORNING
OVER OUR NORTHERN LARAMIE...SNOWY AND SIERRA MADRE RANGES.
THURSDAY...AREAL COVERAGE OF SHOWERS WILL WANE IN THE MORNING AND
EARLY AFTERNOON AS THE SHORTWAVE TROUGH ALOFT DYNAMICS MOVE FAR TO
OUR EAST...THOUGH IT WILL BE A WINDY AND COOL EARLY APRIL DAY WITH
MAXIMUM TEMPERATURES IN THE 40S AT LOWER ELEVATIONS AND 30S OVER THE
MOUNTAINS...PER PROGGED LOW AND MID LEVEL GRADIENTS...700 MB
TEMPERATURES AND THICKNESSES.
THURSDAY NIGHT...ANOTHER WEAKER SHORTWAVE TROUGH ALOFT MOVES OVER
WYOMING WITH ONLY WEAK UPWARD VERTICAL MOTION PRODUCING ISOLATED TO
SCATTERED SHOWERS OVER OUR NORTHERN LARAMIE...SNOWY AND SIERRA MADRE
RANGES. DRY ELSEWHERE.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 330 AM MDT TUE APR 7 2015
WEAK DEPARTING UPPER LEVEL TROUGH EARLY FRIDAY COULD BRING SOME
ISOLATED SHOWERS TO THE MOUNTAINS THROUGH THE AFTERNOON HOURS.
MOST LOCATIONS THOUGH SHOULD REMAIN DRY. 700MB TEMPERATURES ON THE
REBOUND...CLIMBING TO +4C BY SATURDAY. SHOULD SEE UPPER 60S PRETTY
COMMON SATURDAY IN THE PANHANDLE AND LOW 60S OUT WEST.
GFS AND ECMWF SHOWING A WINDY PERIOD AS 700MB WINDS CONTINUE TO
INCREASE. THIS IN RESPONSE TO A LOW PRESSURE SYSTEM TRACKING
ACROSS THE SOUTHERN CANADIAN PROVINCES SUNDAY INTO MONDAY. IN
FACT...GFS FORECAST 50+KTS AT 700MB MONDAY NIGHT...SO WE COULD BE
LOOKING AT WIND HEADLINES FOR OUR WIND PRONE AREAS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1115 PM MDT MON APR 6 2015
LATEST HRRR GUIDANCE USED FOR THE 06Z TAFS. IFR STRATUS MOVING
INTO THE PANHANDLE AND INTO THE EXTREME EAST SOUTHEAST WYOMING
WILL PERSIST THROUGH THE OVERNIGHT HOURS. COULD BE A FAIRLY
PROLONGED EVENT. POSSIBLY LASTING IN THE PANHANDLE INTO THE EARLY
AFTERNOON HOURS.
&&
.FIRE WEATHER...
ISSUED AT 159 AM MDT TUE APR 7 2015
FOR TODAY...SOME CONCERN WEST OF INTERSTATE 25 WHERE
HUMIDITIES IN PORTIONS OF CARBON COUNTY WILL RANGE FROM 15 TO 20
PERCENT IN THE AFTERNOON WITH GUSTY SOUTHWEST WINDS. MINIMAL
CONCERNS ELSEWHERE DUE TO HIGHER HUMIDITIES.
WEDNESDAY...HUMIDITIES WILL BE ABOVE CRITICAL LEVELS...THOUGH FIRE
WEATHER INTERESTS WILL NEED TO WATCH FOR LIGHTNING STRIKES FROM
ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS ALONG AND
EAST OF INTERSTATE 25.
HUMIDITIES DECREASING AGAIN OVER THE WEEKEND WITH SOME GUSTY WINDS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...RUBIN
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...RUBIN
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1118 PM MDT MON APR 6 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 255 PM MDT MON APR 6 2015
TONIGHT:
LATEST WATER VAPOR LOOP WAS SHOWING THE UPPER LEVEL TROF STARTING
TO REACH THE PACIFIC COASTLINE WHILE A 100KT JET CONTINUES TO
NOSE INTO THE BASE OF THIS TROF. ONE INTERESTING NOTE ABOUT THIS
TROF IS THAT THERE IS NOT ANY EVIDENCE OF UPSTREAM ENERGY DIGGING
BEHIND IT BESIDES THE CURRENT JET STREAK. IN ADDITION...THERE IS
NOT A LOT OF JET ENERGY IN THE SOUTHERN STREAM WHICH WILL NOT
FAVOR A DIGGING TROF. AS A RESULT...WE SHOULD SEE THIS TROF
CONTINUE TO SHIFT EAST DURING THE NEXT COUPLE OF DAYS. AHEAD OF
THE TROF...THE SURFACE LEE SIDE TROF WILL BECOME MORE ESTABLISHED
AND START PULLING LOW LEVEL MOISTURE INTO AREAS EAST OF THE
LARAMIE RANGE. WE WILL SEE THE EFFECTS OF THIS LOW LEVEL MOISTURE
LATER TONIGHT IN THE NEBRASKA PANHANDLE WHERE THEY MAY EXPERIENCE
LOW CLOUDS/FOG/LIGHT DRIZZLE. NOT REAL CONFIDENT ABOUT THE DRIZZLE
POTENTIAL SINCE IT APPEARS LIKE THE MOISTURE IS FAIRLY SHALLOW.
HOWEVER...WE COULD SEE THE VISIBILITY DROP TO A 1 MILE IN A FEW
SPOTS.
TUESDAY-TUESDAY NIGHT:
LOW CLOUDS/FOG WILL GRADUALLY SHIFT EAST DURING THE COURSE OF THE
MORNING AS THE BOUNDARY LAYER BEGINS TO MIX OUT. ACROSS THE
WESTERN HALF OF THE AREA...IT WILL CONTINUE TO BE DRY WITH GUSTY
WINDS. HOWEVER...WE MAY START TO SEE SOME ISOLATED CONVECTION
DEVELOP ALONG THE NORTHERN LARAMIE DURING THE EARLY AFTERNOON AS
A JET STREAK MOVES THROUGH THAT REGION AND YIELDS TO SOME UPPER
LEVEL DIFFLUENCE. THIS IS A GOOD SETUP FOR SOME SCATTERED ELEVATED
THUNDERSTORMS WHICH MAY CONTAIN SOME DRY LIGHTNING IN THE NORTHERN
LARAMIE RANGE. WE MAY HAVE TO WATCH THIS POTENTIAL DURING THE
AFTERNOON. THESE THUNDERSTORMS SHOULD PUSH OFF THE MOUNTAINS BY
MID AFTERNOON AND LIFT NORTHEAST BEFORE DISSIPATING EARLY IN THE
EVENING. NOT EXPECTING ANYTHING SEVERE AT THIS TIME DUE TO LIMITED
SHEAR. LOW CLOUDS/FOG WILL ALSO DEVELOP IN AREAS EAST OF THE
LARAMIE RANGE OVERNIGHT DUE TO GOOD UPSLOPE FLOW IN ADVANCE OF THE
UPPER LEVEL TROF.
WEDNESDAY-WEDNESDAY NIGHT:
THE MODELS ARE TRENDING TOWARDS A MUCH MORE PROGRESSIVE SYSTEM
COMPARED TO PREVIOUS RUNS WITH THE SYSTEM REALLY NOT SHOWING ANY
SIGNS OF WRAPPING UP. HOWEVER...THERE IS STILL GOOD POTENTIAL FOR
STRONG/SEVERE THUNDERSTORMS DEVELOPING MAINLY EAST OF THE LARAMIE
RANGE DURING THE AFTERNOON...DUE TO THE JUXTAPOSITION OF THE
SURFACE LEE TROF AND A POTENTIAL VORTICITY ANOMALY MOVING ACROSS.
THESE STORMS COULD EVOLVE INTO A CLUSTER AND SHIFT EAST-SOUTHEAST
DURING THE COURSE OF THE EVENING IN ASSOCIATION WITH THE WAVE. AFTER
THIS CLUSTER MOVES PUSHES EAST...WE WILL SEE THE COLD FRONT START
PLUNGING INTO AREAS EAST OF THE LARAMIE RANGE AND BRING COLDER
TEMPERATURES WITH THE RAIN POSSIBLY CHANGING OVER TO SNOW IN THE
HIGHER ELEVATIONS OF WYOMING. HOWEVER...THIS PRECIPITATION WILL
MOST LIKELY BE SHORT-LIVED DUE TO QUICK FRONTAL FORCING. THE
PANHANDLE STILL LOOKS LIKE IT WILL SEE THE MOST PRECIPITATION IN
THE FORM OF RAINFALL. HOWEVER...THE PINE RIDGE WHERE THEY MAY SEE
SOME SNOW ACCUMULATION WEDNESDAY NIGHT.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 255 PM MDT MON APR 6 2015
LONG RANGE MODELS ARE IN POOR AGREEMENT AND ARE STRUGGLING WITH
THE OVERALL PATTERN IN THE EXTENDED. EVEN ON THURSDAY...MODELS
CONTINUE TO STRUGGLE WITH THE EVOLUTION AND POSITION OF THE
PACIFIC STORM SYSTEM PUSHING EASTWARD INTO THE NORTH-CENTRAL GREAT
PLAINS. ALTHOUGH THE GENERAL TREND HAS BEEN MORE PROGRESSIVE AND A
BIT FURTHER NORTH...IT IS STILL UNCLEAR HOW WIDESPREAD THE
PRECIPITATION WILL BE. A FEW MODELS STILL INDICATE RAPID
CYCLOGENESIS OVER EASTERN COLORADO...BUT OTHERS SUCH AS THE NAM
SHOW LITTLE INDICATION OF ANY CYCLOGENESIS EXCEPT MUCH FURTHER
SOUTH. HOWEVER...BECOMING LESS CONFIDENT THAT A MAJOR STORM WILL
IMPACT THE REGION DURING THE MIDDLE OF THE WEEK GIVEN CURRENT
MODEL TRENDS. WILL NEED TO MONITOR THE POSSIBILITY OF PORTIONS OF
THE FORECAST AREA GETTING CLIPPED BY SOME LOCALLY HEAVY
RAIN/SNOWFALL THROUGH EARLY THURSDAY MORNING. OTHERWISE...LOWERED
POP THROUGH THURSDAY EVENING FOR NOW. TEMPERATURES WILL BE BELOW
NORMAL ON THURSDAY AS WELL WITH HIGHS IN THE 30S TO MID 40S.
FOR LATE IN THE WEEK AND EARLY NEXT WEEKEND...MODELS GENERALLY
SHOW ZONAL FLOW OVER THE AREA WITH A CHANCE OF AFTERNOON SHOWERS
AND ISOLATED THUNDER POSSIBLE. MODEL SOLUTION GREATLY DIVERGE ON
SUNDAY AND MONDAY OF NEXT WEEK...WITH THE GEM AND GFS SHOWING A
STRONG UPPER LEVEL TROUGH PUSHING EASTWARD. THE GFS SHOWS A STRONG
SHORTWAVE LIFTING NORTHEAST AHEAD OF THIS MAIN SYSTEM...WHILE THE
GEM AND ECMWF SHOW THIS SHORTWAVE MUCH FURTHER SOUTH. BY
MONDAY...THE GFS SHOWS THE MAIN UPPER LEVEL TROUGH DIGGING SOUTH
AND STALLING AS THE SOUTHERN SHORTWAVE LIFTS NORTH...FORMING A
DEEP UPPER LEVEL LOW OVER THE DAKOTAS AND EASTERN WYOMING. THE
ECMWF IS MUCH DIFFERENT...SHOWING A CONTINUATION OF NEAR ZONAL
FLOW AS THE MAIN UPPER LEVEL TROUGH LIFTS NORTHEAST BUT IS MUCH
WEAKER COMPARED TO THE GFS. THE FORECAST ENSEMBLES ALSO SHOW ALL
THIS UNCERTAINTY...WITH A WIDE VARIETY OF SOLUTION. IN
ADDITION...SOME ENSEMBLE MEMBERS SHOW THE SOUTHERN SHORTWAVE
PUSHING NORTHWARD...STALLING...AND FORMING A CLOSED LOW OVER
EASTERN COLORADO...WHICH WILL HAVE TO BE MONITORED.
OTHERWISE...DID NOT CHANGE THIS PORTION OF THE FORECAST TOO MUCH
DUE TO ALL THE UNCERTAINTY. HOWEVER...DO EXPECT WARMER
TEMPERATURES ON SATURDAY AND EARLY ON SUNDAY WITH HIGHS IN THE
UPPER 50S TO UPPER 60S...WARMEST ACROSS THE EASTERN PLAINS.
OUTSIDE OF SOME AFTERNOON SHOWERS OR AN ISOLATED TSTORM...IT
SHOULD MAINLY BE DRY ACROSS MOST OF THE FORECAST AREA THIS
WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1115 PM MDT MON APR 6 2015
LATEST HRRR GUIDANCE USED FOR THE 06Z TAFS. IFR STRATUS MOVING
INTO THE PANHANDLE AND INTO THE EXTREME EAST SOUTHEAST WYOMING
WILL PERSIST THROUGH THE OVERNIGHT HOURS. COULD BE A FAIRLY
PROLONGED EVENT. POSSIBLY LASTING IN THE PANHANDLE INTO THE EARLY
AFTERNOON HOURS.
&&
.FIRE WEATHER...
ISSUED AT 255 PM MDT MON APR 6 2015
RED FLAG CONDITIONS WILL PERSIST IN FIRE WEATHER ZONES 302 AND 306
THROUGH THE SUNSET. MEANWHILE...THERE COULD BE A WINDOW FOR MORE
RED FLAG CONDITIONS TOMORROW IN 306 AGAIN FOR LOW HUMIDITIES AND
GUSTY WINDS. HOWEVER...IT LOOKS TO BE RATHER MARGINAL AT THIS TIME
ESPECIALLY WITH CLOUD COVER INCREASING. 302 MAY ALSO SEE THE
POTENTIAL FOR DRY LIGHTNING...BUT WE WILL HOLD OFF ON REISSUING
ANY RED FLAG WARNING FOR THOSE AREAS AND LET THE EVENING/MIDNIGHT
SHIFTS TAKE A CLOSER LOOK. THURSDAY AND FRIDAY WE WILL SEE A BREAK
IN THE RED FLAG CONDITIONS BEFORE NEXT TROF MOVES INTO THE
PICTURE THIS WEEKEND.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...REC
LONG TERM...TJT
AVIATION...GCC
FIRE WEATHER...REC
AREA FORECAST DISCUSSION...UPDATED
NWS LITTLE ROCK AR
1009 AM CDT TUE APR 7 2015
.UPDATE...
NO SIGNIFICANT CHANGES MADE FOR THE MORNING UPDATE. RADAR TRENDS
SHOW THAT PRECIPITATION IS ABOUT TO COME TO AN END ACROSS THE
FORECAST AREA...WITH ONLY SOME ISOLATED THUNDERSTORMS LEFT UP
AROUND THE BATESVILLE AREA AS OF 10 AM. BY NOON ALL RAIN WILL HAVE
EXITED AND EXPECT DRY CONDITIONS FOR THE REST OF TODAY. ADJUSTED
POPS THROUGH THE MORNING TO REFLECT THESE TRENDS...AND HAVE NO
PRECIP MENTIONED FOR THE AFTERNOON PERIOD. TEMPERATURES LOOK ON
TRACK SO NO ADJUSTMENTS THERE EITHER.
&&
.PREV DISCUSSION... /ISSUED 621 AM CDT TUE APR 7 2015/
AVIATION...
SCATTERED LIGHT SHOWERS AND A FEW THUNDERSTORMS WILL CONTINUE THIS
MORNING...WITH PREVAILING CONDITIONS MVFR TO IFR. CONDITIONS WILL
IMPROVE LATE THIS MORNING AND INTO THE AFTERNOON...WITH MOST AREAS
VFR AROUND OR A LITTLE AFTER 18Z. MVFR LOW CLOUDS AND FOG WILL
RETURN LATE TONIGHT...MAINLY AFTER 06Z. WINDS WILL BE SOUTHERLY
AROUND 10 KNOTS TODAY...WITH HIGHER GUSTS. TAS ALREADY OUT.
PREV DISCUSSION... /ISSUED 333 AM CDT TUE APR 7 2015/
SHORT TERM...TODAY THROUGH FRIDAY
SHOWERS AND A FEW THUNDERSTORMS DEVELOPED ACROSS THE STATE DURING
THE OVERNIGHT HOURS WITH SOME PATCHY FOG DEVELOPING. HRRR SUGGESTS
THESE SHOWERS WILL INCREASE IN COVERAGE THROUGH THE EARLY MORNING
HOURS AND KEEP RAIN CHANCES IN THE FORECAST THROUGH THE LATE
MORNING...GENERALLY ACROSS THE EASTERN HALF OF THE STATE.
OTHERWISE...PRECIPITATION WILL BE LIMITED ON TUESDAY WITH A STRONGLY
CAPPED ATMOSPHERE IN PLACE. THE BEST CHANCES FOR
PRECIPITATION...RELATIVELY SPEAKING...WILL BE ACROSS NORTHERN
ARKANSAS...BUT EVEN STILL NOT CONFIDENT ENOUGH TO GO ABOVE SLIGHT
CHANCES. WINDS WILL BE A BIT ON THE STRONG SIDE TODAY...BUT NOT
STRONG ENOUGH TO WARRANT A LAKE WIND ADVISORY.
WEDNESDAY...PRECIPITATION CHANCES WILL SOMEWHAT INCREASE...MAINLY
ACROSS WESTERN ARKANSAS AS A COLD FRONT SLOWLY MARCHES TOWARD THE
STATE. ATMOSPHERE STILL LOOKS TO BE FAIRLY CAPPED ON
WEDNESDAY...HOWEVER UPPER LEVEL RIDGE WILL BEGIN TO PUSH TO THE EAST
ALLOWING TEMPERATURES ALOFT TO SOMEWHAT COOL AND SOMEWHAT WEAKENING
THE CAP.
THURSDAY CONTINUES TO LOOK LIKE THE BEST CHANCE FOR SEVERE WEATHER
ACROSS THE CWA. SURFACE LOW PRESSURE WILL TRACK FROM COLORADO
THROUGH IOWA...DRAGGING ITS ASSOCIATED COLD FRONT THROUGH THE STATE.
MODEL SOUNDINGS TO CONTINUE TO SHOW THE POTENTIAL FOR SEVERE WEATHER
IN THE STATE WILL ALL MODES POSSIBLE. THE COLD FRONT ITSELF WILL NOT
ENTER THE STATE UNTIL 00Z...AND PUSH THROUGH THE STATE BY 12Z
FRIDAY. WITH AMPLE MOISTURE IN PLACE AFTER QUITE A FEW DAYS OF
STRONG SOUTHERLY FLOW...HEAVY RAIN CONTINUES TO BE A CONCERN WITH
THIS SYSTEM.
HIGH PRESSURE AND DRY WEATHER WILL MOVE INTO THE STATE FOR
FRIDAY...WITH THE FRONT STALLING JUST TO THE SOUTH OF THE STATE.
TEMPERATURES WILL RETURN TO NEAR NORMAL LEVELS.
LONG TERM...FRIDAY NIGHT THROUGH MONDAY
HIGH PRESSURE WILL BE MOVING THROUGH THE AREA ON FRIDAY NIGHT...WITH
THE FRONT STALLED OUT JUST TO THE SOUTH OF THE REGION. THE HIGH WILL
MOVE EASTWARD ON SATURDAY...WITH RETURN FLOW SETTING UP AS THE FRONT
BEGINS TO BACK NORTHWARD. SHOWERS AND THUNDERSTORMS WILL RETURN TO
THE FORECAST...WITH THE HIGHEST CHANCES ON SUNDAY AND SUNDAY NIGHT...
AS THE WARM FRONT MOVES THROUGH...ALONG WITH AN UPPER TROUGH WITH A
BIT OF A NEGATIVE TILT. EXTENDED RANGE MODELS ARE SHOWING A SURFACE
LOW DEVELOPING SUNDAY NIGHT INTO MONDAY...DRAGGING A COLD FRONT INTO
THE REGION DURING THE DAY.
IF THE AFOREMENTIONED SCENARIO PANS OUT...SEVERE THUNDERSTORMS MAY
BE POSSIBLE. ALSO...WITH GULF AND PACIFIC MOISTURE LINING UP...
PRECIPITABLE WATER VALUES WILL BE APPROACHING TWO INCHES. THUS...
HEAVY RAINFALL WOULD BE A POSSIBILITY AS WELL. WILL CONTINUE TO
MONITOR THIS POTENTIAL HAZARDOUS WEATHER SETUP...AND ADJUST
SUCCESSIVE FORECASTS ACCORDINGLY. ONE THING THAT IS CONCERNING IS
THAT...THOUGH THE SMALL DETAILS DIFFER TO VARYING DEGREES...THE
MODELS ARE IN REMARKABLY GOOD AGREEMENT FOR SIX DAYS OUT. STAY
TUNED.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 80 65 82 65 / 30 10 20 30
CAMDEN AR 83 65 84 66 / 20 10 10 20
HARRISON AR 80 63 82 63 / 10 20 20 40
HOT SPRINGS AR 81 67 82 66 / 20 10 10 20
LITTLE ROCK AR 82 66 83 65 / 30 10 10 20
MONTICELLO AR 82 65 84 67 / 20 10 10 10
MOUNT IDA AR 80 66 79 67 / 10 10 10 30
MOUNTAIN HOME AR 79 63 83 63 / 20 20 20 40
NEWPORT AR 80 65 82 66 / 30 20 20 20
PINE BLUFF AR 82 65 83 65 / 30 10 10 20
RUSSELLVILLE AR 81 63 83 64 / 20 10 20 30
SEARCY AR 80 63 82 64 / 30 10 20 20
STUTTGART AR 81 66 82 66 / 30 10 10 20
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
64
AREA FORECAST DISCUSSION...UPDATED
NWS LITTLE ROCK AR
621 AM CDT TUE APR 7 2015
.AVIATION...
SCATTERED LIGHT SHOWERS AND A FEW THUNDERSTORMS WILL CONTINUE THIS
MORNING...WITH PREVAILING CONDITIONS MVFR TO IFR. CONDITIONS WILL
IMPROVE LATE THIS MORNING AND INTO THE AFTERNOON...WITH MOST AREAS
VFR AROUND OR A LITTLE AFTER 18Z. MVFR LOW CLOUDS AND FOG WILL
RETURN LATE TONIGHT...MAINLY AFTER 06Z. WINDS WILL BE SOUTHERLY
AROUND 10 KNOTS TODAY...WITH HIGHER GUSTS. TAS ALREADY OUT.
&&
.PREV DISCUSSION... /ISSUED 333 AM CDT TUE APR 7 2015/
SHORT TERM...TODAY THROUGH FRIDAY
SHOWERS AND A FEW THUNDERSTORMS DEVELOPED ACROSS THE STATE DURING
THE OVERNIGHT HOURS WITH SOME PATCHY FOG DEVELOPING. HRRR SUGGESTS
THESE SHOWERS WILL INCREASE IN COVERAGE THROUGH THE EARLY MORNING
HOURS AND KEEP RAIN CHANCES IN THE FORECAST THROUGH THE LATE
MORNING...GENERALLY ACROSS THE EASTERN HALF OF THE STATE.
OTHERWISE...PRECIPITATION WILL BE LIMITED ON TUESDAY WITH A STRONGLY
CAPPED ATMOSPHERE IN PLACE. THE BEST CHANCES FOR
PRECIPITATION...RELATIVELY SPEAKING...WILL BE ACROSS NORTHERN
ARKANSAS...BUT EVEN STILL NOT CONFIDENT ENOUGH TO GO ABOVE SLIGHT
CHANCES. WINDS WILL BE A BIT ON THE STRONG SIDE TODAY...BUT NOT
STRONG ENOUGH TO WARRANT A LAKE WIND ADVISORY.
WEDNESDAY...PRECIPITATION CHANCES WILL SOMEWHAT INCREASE...MAINLY
ACROSS WESTERN ARKANSAS AS A COLD FRONT SLOWLY MARCHES TOWARD THE
STATE. ATMOSPHERE STILL LOOKS TO BE FAIRLY CAPPED ON
WEDNESDAY...HOWEVER UPPER LEVEL RIDGE WILL BEGIN TO PUSH TO THE EAST
ALLOWING TEMPERATURES ALOFT TO SOMEWHAT COOL AND SOMEWHAT WEAKENING
THE CAP.
THURSDAY CONTINUES TO LOOK LIKE THE BEST CHANCE FOR SEVERE WEATHER
ACROSS THE CWA. SURFACE LOW PRESSURE WILL TRACK FROM COLORADO
THROUGH IOWA...DRAGGING ITS ASSOCIATED COLD FRONT THROUGH THE STATE.
MODEL SOUNDINGS TO CONTINUE TO SHOW THE POTENTIAL FOR SEVERE WEATHER
IN THE STATE WILL ALL MODES POSSIBLE. THE COLD FRONT ITSELF WILL NOT
ENTER THE STATE UNTIL 00Z...AND PUSH THROUGH THE STATE BY 12Z
FRIDAY. WITH AMPLE MOISTURE IN PLACE AFTER QUITE A FEW DAYS OF
STRONG SOUTHERLY FLOW...HEAVY RAIN CONTINUES TO BE A CONCERN WITH
THIS SYSTEM.
HIGH PRESSURE AND DRY WEATHER WILL MOVE INTO THE STATE FOR
FRIDAY...WITH THE FRONT STALLING JUST TO THE SOUTH OF THE STATE.
TEMPERATURES WILL RETURN TO NEAR NORMAL LEVELS.
LONG TERM...FRIDAY NIGHT THROUGH MONDAY
HIGH PRESSURE WILL BE MOVING THROUGH THE AREA ON FRIDAY NIGHT...WITH
THE FRONT STALLED OUT JUST TO THE SOUTH OF THE REGION. THE HIGH WILL
MOVE EASTWARD ON SATURDAY...WITH RETURN FLOW SETTING UP AS THE FRONT
BEGINS TO BACK NORTHWARD. SHOWERS AND THUNDERSTORMS WILL RETURN TO
THE FORECAST...WITH THE HIGHEST CHANCES ON SUNDAY AND SUNDAY NIGHT...
AS THE WARM FRONT MOVES THROUGH...ALONG WITH AN UPPER TROUGH WITH A
BIT OF A NEGATIVE TILT. EXTENDED RANGE MODELS ARE SHOWING A SURFACE
LOW DEVELOPING SUNDAY NIGHT INTO MONDAY...DRAGGING A COLD FRONT INTO
THE REGION DURING THE DAY.
IF THE AFOREMENTIONED SCENARIO PANS OUT...SEVERE THUNDERSTORMS MAY
BE POSSIBLE. ALSO...WITH GULF AND PACIFIC MOISTURE LINING UP...
PRECIPITABLE WATER VALUES WILL BE APPROACHING TWO INCHES. THUS...
HEAVY RAINFALL WOULD BE A POSSIBILITY AS WELL. WILL CONTINUE TO
MONITOR THIS POTENTIAL HAZARDOUS WEATHER SETUP...AND ADJUST
SUCCESSIVE FORECASTS ACCORDINGLY. ONE THING THAT IS CONCERNING IS
THAT...THOUGH THE SMALL DETAILS DIFFER TO VARYING DEGREES...THE
MODELS ARE IN REMARKABLY GOOD AGREEMENT FOR SIX DAYS OUT. STAY
TUNED.
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AVIATION...57
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
434 AM PDT TUE APR 7 2015
...LATE SEASON STORM TO IMPACT THE REGION THROUGH TONIGHT...
.SYNOPSIS...RAIN WILL GO THROUGH OUR AREA THIS MORNING. ALONG
WITH LOCALLY HEAVY RAINFALL...THUNDERSTORMS WITH SMALL HAIL AND
GUSTY WINDS WILL BE POSSIBLE AS THE SYSTEM MOVES INLAND. IN
ADDITION...SNOW ACCUMULATIONS WILL BE POSSIBLE OVER THE SANTA
LUCIA RANGE ABOVE 4000 FEET. DRY WEATHER CONDITIONS RETURN BY
MIDWEEK AS THE SYSTEM EXITS THE REGION.
&&
.DISCUSSION...AS OF 3:00 AM PDT TUESDAY...AS EXPECTED RADAR
RETURNS HAVE INCREASED THROUGH THE OVERNIGHT HOURS AS A STRONG
FRONT MOVES ACROSS OUR AREA. LATEST LOOK AT KMUX SHOWS A BAND OF
MODERATE RAIN ENTERING THE SF BAY REGION ASSOCIATED WITH THE
HEAVILY ADVERTISED COLD FRONT. SO FAR RAINFALL RETURNS HAVE BEEN
DECENT WITH PARTS OF SONOMA COUNTY OVER THREE QUARTERS OF AN
INCH. LATEST RUN OF THE HRRR SHOWS THE BEST POTENTIAL FOR MODERATE
TO POSSIBLY HEAVY RAINFALL THROUGH THE MORNING HOURS IN A REGION
FROM THE SOUTH BAY OVER TO THE FAR EAST BAY VALLEYS AND THEN SOUTH
INTO SANTA CRUZ COUNTY. THOSE SPOTS COULD EASILY SEE HALF AN INCH
BY MID-MORNING.
WINDS PICKED UP THROUGH THE EVENING HOURS ALTHOUGH STRONG GUSTS
GENERALLY HAVE BEEN CONFINED TO HIGHER ELEVATION SPOTS. A FEW
URBAN AREAS ARE SEEING GUSTS OVER 25 MPH INCLUDING BOTH THE SFO
AND OAKLAND AIRPORTS. FOR SPOTS OVER 1000 FEET GUSTS OVER 35 MPH
ARE FAIRLY COMMON ESPECIALLY FOR OUR TYPICAL WINDY SPOTS.
BEHIND THE COLD FRONT THE ATMOSPHERE WILL DESTABILIZE WITH LIFTED
VALUES EXPECTED TO DROP AS LOW AS MINUS 3 WHILE CAPE VALUES COULD
EXCEED 200 J/KG. WOULD EXPECT AT LEAST A FEW THUNDERSTORMS ACROSS
OUR AREA ALONG WITH REPORTS OF SMALL HAIL. WORTH NOTING THAT VERY
LITTLE DIRECTIONAL SHEER IS FORECAST FOR OUR AREA WITH ONLY
LIMITED SPEED SHEER WHICH WILL HELP TO LIMIT THE THREAT OF SEVERE
WEATHER. THE COOLER AIR WILL LEAD TO LOWER SNOW LEVELS WITH
ACCUMULATIONS EXPECTED OVER 4000 FEET. STILL LOOKS LIKE THE SANTA
LUCIA RANGE COULD PICK UP 3 TO 6 INCHES OF SNOW.
ALL TOO FAMILIAR RIDGE OF HIGH PRESSURE WILL BUILD BACK TO OUR AREA
STARTING ON WEDNESDAY AS THE SYSTEM DEPARTS TO THE EAST. THIS
WILL LEAD TO THE STORM TRACK HEADING BACK WELL TO THE NORTH ALONG
WITH WARMER TEMPERATURES. LONGER RANGE OUTLOOKS DO NOT INDICATE
ANY ADDITIONAL SUBSTANTIAL STORMS PAST TODAY GOING ALL OF THE WAY
TO APRIL 20TH.
&&
.AVIATION...AS OF 04:27 AM PDT TUESDAY...A COLD FRONT IS CURRENTLY
TRAVERSING THE BAY AREA BRINGING RAIN AND GUSTY WINDS. FOR THE
MOST PART FLIGHT CAT ARE VFR WITH A FEW POCKETS OF MVFR. THE
IMPACT TO TERMINALS WILL BE EARLY THIS MORNING THROUGH THE
MORNING RUSH WITH WET RUNWAYS AND WIND. FOLLOWING SHORT TERM
MODELS...RAIN WILL TAPER OFF FROM N-S AFTER 14/15Z. STEADIER RAIN
TRANSITIONS TO HIT MORE MISS SHOWERS/CONVECTIVE NATURE. WINDS WILL ALSO DIMINISH
AFTER 15Z. VFR CONDITIONS TONIGHT. CONF IS MEDIUM.
VICINITY OF KSFO...TIMING OF PERSISTENT RAINFALL THROUGH APPROX
15Z WITH GUSTY WINDS.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...RAIN THROUGH MID MORNING THEN VCSH
THIS AFTERNOON.
&&
.MARINE...AS OF 04:26 AM PDT TUESDAY...A COLD FRONT WILL MOVE
THROUGH THE COASTAL WATERS EARLY TODAY PRODUCING GUSTY
WINDS...RAIN AND THUNDERSTORMS. THE GUSTY WINDS WILL PRODUCE
LOCALLY HAZARDOUS CONDITIONS. WINDS WILL DECREASE FROM NORTH TO
SOUTH THROUGH THE DAY AS THE FRONT EXITS THE REGION WITH AN
IMPROVING SEA STATE. NORTHWEST SWELL THROUGH THE PERIOD.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...WINTER WEATHER ADVISORY...SANTA LUCIA RANGE THROUGH
TONIGHT.
SCA...SF BAY NORTH OF THE BAY BRIDGE UNTIL 8 AM
SCA...SF BAY SOUTH OF THE BAY BRIDGE UNTIL 8 AM
SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 8 AM
SCA...PIGEON PT TO PT PINOS 0-10 NM UNTIL 8 AM
SCA...PT REYES TO PIGEON PT 10-60 NM UNTIL 8 AM
SCA...PIGEON PT TO PT PINOS 10-60 NM UNTIL 8 AM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM UNTIL 11 AM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM UNTIL 11 AM
&&
$$
PUBLIC FORECAST: BELL
AVIATION/MARINE: MM
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AREA FORECAST DISCUSSION
NWS MIAMI FL
1118 AM EDT TUE APR 7 2015
.UPDATE...
JUST MADE A QUICK CHANGE TO ADD A SLIGHT CHANCE OF THUNDER OVER
THE INTERIOR AND WEST COAST FOR LATE THIS AFTERNOON AND EARLY
EVENING. THIS BASED ON CLOSER EXAMINATION TO THE MORNING SOUNDING
AND DECIDED THE AIRMASS IS SHOWING ENOUGH INSTABILITY THAT CANNOT
RULE OUT A POSSIBLE LIGHTNING STRIKE.
&&
.PREV DISCUSSION... /ISSUED 902 AM EDT TUE APR 7 2015/
UPDATE...
CURRENT ANALYSIS SHOWS MID/UPPER LEVEL RIDGE OVER THE EASTERN GULF
OF MEXICO AND SURFACE RIDGE FROM THE SOUTHEAST STATES INTO THE
ATLANTIC. DO NOT PLAN TO MAKE ANY MAJOR CHANGES WITH THE MORNING
UPDATES. THE 12Z MFL SOUNDING SHOWS MARGINAL INSTABILITY BUT STILL
QUITE DRY WITH PWAT AT LESS THAN 1.5" WHICH IS SLIGHTLY ABOVE THE
EARLY APRIL AVERAGE OF AROUND 1.2". SO THIS COMBINED WITH PLENTY
OF DIURNAL HEATING ALONG WITH A WELL ESTABLISHED LOW LEVEL
SOUTHEAST FLOW WILL RESULT IN A FEW LATE AFTERNOON/EARLY EVENING
SHOWERS OVER THE INTERIOR AND WEST COAST. THE HRRR SHOWS THIS
ACTIVITY BEGINNING AROUND 19Z AND PERSISTING UNTIL 01-02Z THIS
EVENING. THIS SEEMS REASONABLE BASED ON THE ABOVE DISCUSSION.
KOB
PREV DISCUSSION... /ISSUED 811 AM EDT TUE APR 7 2015/
AVIATION...
HIGH PRESSURE WILL BE BUILDING OVER THE AREA, WITH THE CENTER NEAR
BERMUDA. THIS WILL KEEP THE GENERAL FLOW OUT OF THE EAST TODAY.
SOME ISOLATED SHOWERS MAY BE POSSIBLE ALONG THE GULF COAST. A WEAK
UPPER LEVEL TROUGH WILL MOVE OVER SOUTH FLORIDA TONIGHT, BRINGING
AT LEAST AN INCREASE IN CLOUD COVER. SOME MODELS ARE INDICATING
THE CIGS COULD BE BORDERING ON IFR AT SOME OF THE ATLANTIC TAF
SITES, BEGINNING AFTER 02Z. HOWEVER, WITH LOW CONFIDENCE OF THE
IFR CONDITIONS, KEPT THE TAF STATING VFR AT THIS TIME.
PREV DISCUSSION... /ISSUED 323 AM EDT TUE APR 7 2015/
DISCUSSION...
ABOVE NORMAL HIGH AND LOW TEMPERATURES ARE EXPECTED EACH DAY
THROUGH THE FORECAST PERIOD...WITH HIGHS IN THE 80S TO LOW 90S AND
LOWS IN THE MID 60S TO MID 70S. SHOWERS ARE POSSIBLE TODAY AND
WEDNESDAY FOR THE GULF COAST...WITH DRY CONDITIONS ON THURSDAY.
SEA BREEZE SHOWERS AND THUNDERSTORMS RETURN TO THE REGION FRIDAY
THROUGH THE WEEKEND...ESPECIALLY INTERIOR AND WEST.
SHOWERS OVER THE GULF COAST AND ATLANTIC WATERS HAVE
DIMINISHED...BUT A FEW SPRINKLES ARE POSSIBLE ALONG THE EAST COAST
OVER THE NEXT COUPLE HOURS. EASTERLY WINDS TODAY WILL BE IN THE
10-15 MPH RANGE AS SURFACE HIGH PRESSURE SETTLES OVER THE WESTERN
ATLANTIC. A WEAK SHORTWAVE WILL SLIDE SOUTHEAST DOWN THE
PENINSULA THIS AFTERNOON AND INTO THE REGION THIS EVENING. THIS
MAY ENHANCE SHOWERS ALONG THE SEA BREEZE THIS AFTERNOON...BUT THE
BEST LIFT WILL BE ACROSS CENTRAL FLORIDA SO WILL LEAVE MENTION OF
THUNDERSTORMS OUT TODAY. LOW LEVEL MOISTURE WILL INCREASE IN THE
EVENING FOR THE EAST COAST...AND WITH THE SHORTWAVE MOVING INTO
THE REGION...A FEW SHOWERS ARE POSSIBLE. SOME LOWER CEILINGS ARE
ALSO POSSIBLE FOR THE EAST COAST.
A SHORTWAVE TROUGH WILL MOVE INTO THE INTERMOUNTAIN WEST ON
WEDNESDAY...AND THE MID/UPPER RIDGE OVER THE GULF WILL AMPLIFY
ACROSS THE EASTERN SEABOARD. A FEW SHOWERS ARE STILL POSSIBLE
ALONG THE GULF COAST SEA BREEZE...BUT OVERALL ACTIVITY WILL BE
LIMITED.
MID/UPPER LEVEL RIDGING WILL THEN TAKE OVER THE WEATHER ON
THURSDAY. THE SHORTWAVE TROUGH WILL LIFT NORTHEASTWARD INTO THE
GREAT LAKES ON FRIDAY...AND THE MID/UPPER LEVEL RIDGE WILL SHIFT
INTO THE WESTERN ATLANTIC. SURFACE HIGH PRESSURE WILL PUSH
EASTWARD...AND SOUTHEAST LOW LEVEL FLOW WILL ALLOW DEEPER MOISTURE
TO PUSH INTO THE REGION. SO SCATTERED SHOWERS AND STORMS ARE
POSSIBLE ALONG THE SEA BREEZE CONVERGENCE ACROSS THE INTERIOR AND
GULF COAST. SIMILAR CONDITIONS ARE EXPECTED ON SATURDAY...WITH THE
BEST CHANCE OF SHOWERS AND STORMS ACROSS THE INTERIOR AND GULF
COAST.
AN UPPER TROUGH WILL THEN DIG ACROSS THE MIDDLE OF THE COUNTRY
SUNDAY INTO SUNDAY NIGHT...WITH THE MID/UPPER RIDGE AMPLIFYING
ACROSS THE REGION ONCE AGAIN INTO EARLY NEXT WEEK. SEA BREEZE
SHOWERS AND STORMS ARE POSSIBLE ON SUNDAY...WITH DRIER CONDITIONS
THEN RETURNING TO THE REGION.
MARINE...
AN EAST TO SOUTHEAST WIND WILL CONTINUE THROUGH THE PERIOD WITH
SEAS OF 2-4 FEET OVER THE ATLANTIC WATERS AND 1-2 FEET IN THE GULF
WATERS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 84 72 85 73 / 10 10 10 0
FORT LAUDERDALE 83 73 83 73 / 10 10 10 0
MIAMI 86 72 85 73 / 10 10 10 0
NAPLES 87 69 89 68 / 20 20 20 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...10/CD
LONG TERM....10/CD
AREA FORECAST DISCUSSION
NWS MIAMI FL
902 AM EDT TUE APR 7 2015
.UPDATE...
CURRENT ANALYSIS SHOWS MID/UPPER LEVEL RIDGE OVER THE EASTERN GULF
OF MEXICO AND SURFACE RIDGE FROM THE SOUTHEAST STATES INTO THE
ATLANTIC. DO NOT PLAN TO MAKE ANY MAJOR CHANGES WITH THE MORNING
UPDATES. THE 12Z MFL SOUNDING SHOWS MARGINAL INSTABILITY BUT STILL
QUITE DRY WITH PWAT AT LESS THAN 1.5" WHICH IS SLIGHTLY ABOVE THE
EARLY APRIL AVERAGE OF AROUND 1.2". SO THIS COMBINED WITH PLENTY
OF DIURNAL HEATING ALONG WITH A WELL ESTABLISHED LOW LEVEL
SOUTHEAST FLOW WILL RESULT IN A FEW LATE AFTERNOON/EARLY EVENING
SHOWERS OVER THE INTERIOR AND WEST COAST. THE HRRR SHOWS THIS
ACTIVITY BEGINNING AROUND 19Z AND PERSISTING UNTIL 01-02Z THIS
EVENING. THIS SEEMS REASONABLE BASED ON THE ABOVE DISCUSSION.
KOB
&&
.PREV DISCUSSION... /ISSUED 811 AM EDT TUE APR 7 2015/
AVIATION...
HIGH PRESSURE WILL BE BUILDING OVER THE AREA, WITH THE CENTER NEAR
BERMUDA. THIS WILL KEEP THE GENERAL FLOW OUT OF THE EAST TODAY.
SOME ISOLATED SHOWERS MAY BE POSSIBLE ALONG THE GULF COAST. A WEAK
UPPER LEVEL TROUGH WILL MOVE OVER SOUTH FLORIDA TONIGHT, BRINGING
AT LEAST AN INCREASE IN CLOUD COVER. SOME MODELS ARE INDICATING
THE CIGS COULD BE BORDERING ON IFR AT SOME OF THE ATLANTIC TAF
SITES, BEGINNING AFTER 02Z. HOWEVER, WITH LOW CONFIDENCE OF THE
IFR CONDITIONS, KEPT THE TAF STATING VFR AT THIS TIME.
PREV DISCUSSION... /ISSUED 323 AM EDT TUE APR 7 2015/
DISCUSSION...
ABOVE NORMAL HIGH AND LOW TEMPERATURES ARE EXPECTED EACH DAY
THROUGH THE FORECAST PERIOD...WITH HIGHS IN THE 80S TO LOW 90S AND
LOWS IN THE MID 60S TO MID 70S. SHOWERS ARE POSSIBLE TODAY AND
WEDNESDAY FOR THE GULF COAST...WITH DRY CONDITIONS ON THURSDAY.
SEA BREEZE SHOWERS AND THUNDERSTORMS RETURN TO THE REGION FRIDAY
THROUGH THE WEEKEND...ESPECIALLY INTERIOR AND WEST.
SHOWERS OVER THE GULF COAST AND ATLANTIC WATERS HAVE
DIMINISHED...BUT A FEW SPRINKLES ARE POSSIBLE ALONG THE EAST COAST
OVER THE NEXT COUPLE HOURS. EASTERLY WINDS TODAY WILL BE IN THE
10-15 MPH RANGE AS SURFACE HIGH PRESSURE SETTLES OVER THE WESTERN
ATLANTIC. A WEAK SHORTWAVE WILL SLIDE SOUTHEAST DOWN THE
PENINSULA THIS AFTERNOON AND INTO THE REGION THIS EVENING. THIS
MAY ENHANCE SHOWERS ALONG THE SEA BREEZE THIS AFTERNOON...BUT THE
BEST LIFT WILL BE ACROSS CENTRAL FLORIDA SO WILL LEAVE MENTION OF
THUNDERSTORMS OUT TODAY. LOW LEVEL MOISTURE WILL INCREASE IN THE
EVENING FOR THE EAST COAST...AND WITH THE SHORTWAVE MOVING INTO
THE REGION...A FEW SHOWERS ARE POSSIBLE. SOME LOWER CEILINGS ARE
ALSO POSSIBLE FOR THE EAST COAST.
A SHORTWAVE TROUGH WILL MOVE INTO THE INTERMOUNTAIN WEST ON
WEDNESDAY...AND THE MID/UPPER RIDGE OVER THE GULF WILL AMPLIFY
ACROSS THE EASTERN SEABOARD. A FEW SHOWERS ARE STILL POSSIBLE
ALONG THE GULF COAST SEA BREEZE...BUT OVERALL ACTIVITY WILL BE
LIMITED.
MID/UPPER LEVEL RIDGING WILL THEN TAKE OVER THE WEATHER ON
THURSDAY. THE SHORTWAVE TROUGH WILL LIFT NORTHEASTWARD INTO THE
GREAT LAKES ON FRIDAY...AND THE MID/UPPER LEVEL RIDGE WILL SHIFT
INTO THE WESTERN ATLANTIC. SURFACE HIGH PRESSURE WILL PUSH
EASTWARD...AND SOUTHEAST LOW LEVEL FLOW WILL ALLOW DEEPER MOISTURE
TO PUSH INTO THE REGION. SO SCATTERED SHOWERS AND STORMS ARE
POSSIBLE ALONG THE SEA BREEZE CONVERGENCE ACROSS THE INTERIOR AND
GULF COAST. SIMILAR CONDITIONS ARE EXPECTED ON SATURDAY...WITH THE
BEST CHANCE OF SHOWERS AND STORMS ACROSS THE INTERIOR AND GULF
COAST.
AN UPPER TROUGH WILL THEN DIG ACROSS THE MIDDLE OF THE COUNTRY
SUNDAY INTO SUNDAY NIGHT...WITH THE MID/UPPER RIDGE AMPLIFYING
ACROSS THE REGION ONCE AGAIN INTO EARLY NEXT WEEK. SEA BREEZE
SHOWERS AND STORMS ARE POSSIBLE ON SUNDAY...WITH DRIER CONDITIONS
THEN RETURNING TO THE REGION.
MARINE...
AN EAST TO SOUTHEAST WIND WILL CONTINUE THROUGH THE PERIOD WITH
SEAS OF 2-4 FEET OVER THE ATLANTIC WATERS AND 1-2 FEET IN THE GULF
WATERS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 84 72 85 73 / 10 10 10 0
FORT LAUDERDALE 83 73 83 73 / 10 10 10 0
MIAMI 86 72 85 73 / 10 10 10 0
NAPLES 87 69 89 68 / 20 20 20 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1043 AM CDT Tue Apr 7 2015
.UPDATE...
ISSUED AT 1040 AM CDT TUE APR 7 2015
Will update the forecast around 11 am when dense fog advisory over
central IL expires. Some patchy fog may linger into midday over areas
north of I-70 but most of the dense fog over central IL should
lift late this morning. A frontal boundary has sagged southward
into central IL near I-72 late this morning and HRRR models keeps
this boundary near I-72 into early evening. 1007 mb surface low
pressure over ne KS will track into nw MO early this evening and
tug front slowly back north during tonight. Have cooled highs
north of this boundary with upper 50s and lower 60s for highs from
Galesburg, Peoria and Bloomington north where low clouds persist.
Showers south of I-72 with thunderstorms from Litchfied sw and
some strong to severe with heavy rains from St Louis south. Severe
storms should stay along and south of I-64 today though a few
thunderstorms could affect areas from I-72 south this afternoon
along and south of the boundary. Milder highs in low to mid 70s in
sw CWA from Springfield to Terre Haute sw where some peaks of
sunshine to appear during the afternoon.
&&
.SHORT TERM...(Today)
ISSUED AT 335 AM CDT TUE APR 7 2015
A few showers and isolated thunderstorms will continue to move
across southeast Illinois early this morning. HiRes short term
models develop another area of showers and isolated thunderstorms
over northern MO and then bring them into central IL late morning
and into the afternoon. The warm front has setup and is sitting
right through central IL, north of a Quincy to Springfield to
Mattoon line, which puts half of the cwa south of the front, and
the I-74 area, including Lincoln, north of the front. So, area of
convection that does develop should follow along and just north of
the front when it arrives later this morning. So, have likely pops
in the southeast for this morning, and then slightly higher pops
in the afternoon for the west central. With front right across CWA
high temp spread with be around 15 degrees across the CWA today.
Cloud cover will also be persistent today, with some light fog
this morning. With pcpn being mainly scattered, qpf values will
not be that significant.
&&
.LONG TERM...(Tonight through Monday)
ISSUED AT 335 AM CDT TUE APR 7 2015
The warm front should become a little more active this evening and
shift north, as the first in a series of low pressure areas moves
along the frontal zone. So, higher pcpn chances will be in the
north for tonight with chance pops remaining for the rest of the
area, which will be in the warm sector. Lowest pops will be in the
south. As this first low moves east, it will drag the cold front
south through the cwa, so pops for Wed morning will be higher to
the south and only a slight chance in the north. However, the next
wave/low press area will lift out Wed afternoon and return chance
pops for the whole area. This one will lift northeast through the
area and bring much higher chances of pcpn to the CWA for late Wed
afternoon through Wed night. Per SPC day 2 outlook, there is a
slight risk of severe weather nosing into west central IL for late
Wed afternoon and into Wed night. Highest pops will be west of
I-55. Probably will be a little break Wed night after midnight,
but will not put that in just yet.
Then on Thursday, the main sfc system will lift out of the plains
with the associated mid level wave. Though there may be pcpn
ongoing Thur morning in the east, by afternoon most of the area
should be pcpn free and the atmosphere should be able to recover
before the next round of pcpn. Forecasted CAPE values will be 2000
to 2500 across a good portion of IL in the warm sector ahead of
the front. A strong upper level jet will also be pushing into the
area at the same time, so wind dynamics and shear will be
sufficient that storms will likely rotate. There is still some
uncertainty as to how this will play out Thur given the Wed night
and early morning convection, but if airmass recovers, it looks
like a line of convection will develop just west of the state late
afternoon and then move east across the state Thur evening. All
forms of severe weather look to be possible late afternoon through
the evening hours. Something to consider is that storms may be
moving at about 40-45 mph. By midnight, most of the storms should
be east of the state, but will hang on to some chance pops.
Past this system, dry conditions are expected for Fri through Sat
night. Then another system moves toward the area for Sunday
through Monday with more showers and storms.
Expecting very warm temps for Thur, but then temps will cool some
Fri and Sat, but warm back a tad for Sun and Mon.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
ISSUED AT 615 AM CDT TUE APR 7 2015
LIFR to VLIFR conditions in fog and low stratus will be the main
forecast concern early on this morning, with a gradual improvement
to MVFR cigs/vsbys by or shortly aftr 15z this morning. A stalled
frontal boundary over central Illinois will not move much today
with areas just to the south possibly seeing cigs improve to low
VFR for a time this afternoon before all areas go back to IFR
conditions again tonight. Timing and coverage of showers and
TSRA rather complicated for today so VCSH or VCTS will be included
in areas and times where we see the better threat. Surface winds
will be east to northeast at BMI and PIA with speeds of 10 to 15
kts today, with surface winds more southeast in our southern TAF
sites which were south of the stalled frontal boundary. Winds
in those locations will also average from 10 to 15 kts.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY until 11 AM CDT this morning FOR ILZ027>031-
036>038-040>057-061.
&&
$$
UPDATE...07
SHORT TERM...Auten
LONG TERM...Auten
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
614 AM CDT TUE APR 7 2015
...UPDATED AVIATION SECTION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT TUE APR 7 2015
A COLD FRONT WAS SLOWLY PUSHING SOUTH ACROSS CENTRAL AND SOUTHWEST
KANSAS EARLY THIS MORNING. MOIST UPSLOPE FLOW TO THE NORTH OF THE
FRONT WAS RESULTING IN WIDESPREAD STRATUS AND FOG GENERALLY ALONG
AND NORTH OF A LINE FROM LACROSSE TO NEAR DODGE CITY THEN WEST
THROUGH GARDEN CITY AND SYRACUSE. AREAS IMMEDIATELY NORTH OF THE
FRONT WERE SEEING DENSE FOG DEVELOP. THE PAST SEVERAL RUNS OF THE
RUC13 AND HRRR HAVE BEEN INDICATING THIS AND THEY HAVE GENERALLY
TENDED TO MOVE IT SLOWLY SOUTHWARD BEFORE DISSIPATING IT AFTER
SUNRISE. WILL ISSUE A DENSE FOG ADVISORY FOR THIS AREA THROUGH
ABOUT 8 AM CDT.
THE FOG AND STRATUS SHOULD ERODE NORTHWARD THROUGH THE MORNING
HOURS WITH AREAS ALONG I-70 SCATTERING OUT EARLY THIS AFTERNOON.
FOR THE REST OF TODAYS FORECAST, HAVE ONLY MADE A FEW MINOR
ADJUSTMENTS. THE FRONT MAY MOVE A LITTLE MORE SOUTHWARD THIS
MORNING AS INDICATED BY THE SHORT TERM MODELS BUT THE SOUTHERN
PORTION OF THE FRONT SHOULD MIX OUT THROUGH THIS AFTERNOON. MOS
GUIDANCE IS PRETTY SIMILAR OVER WESTERN SECTIONS OF THE CWA BUT
DIFFERS MORE IN THE EAST WHERE THE COOLER MET MOS KEEPS HIGHS IN
THE UPPER 60S WHILE THE MAV GUIDANCE WARMS CENTRAL KANSAS INTO THE
MID 70S. GIVEN THAT THERE WILL BE STRATUS ERODING THROUGH PART OF
THE DAY, HAVE CONTINUED TO LEAN TOWARD THE COOLER GUIDANCE FOR
THAT AREA.
TONIGHT WILL SEE STRATUS REDEVELOPING ALONG WITH SOME PATCHY FOG
AND DRIZZLE ESPECIALLY IN THE WAKEENEY, HAYS AND LACROSSE AREAS.
MODEL SOUNDINGS ARE STILL SHOWING LOW LEVEL WARM ADVECTION
MAXIMIZED IN THAT AREA AROUND OR AFTER MIDNIGHT. IF ANY PARCELS
CAN GET LIFTED ENOUGH, THERE WILL BE SOME INSTABILITY ALOFT THAT
COULD SUPPORT A FEW THUNDERSTORMS. WILL LEAVE A MENTION OF ISOLATED
THUNDERSTORMS IN THAT AREA AS WELL.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 319 AM CDT TUE APR 7 2015
AN UPPER LEVEL LOW WILL BE POSITIONED OVER THE INTERMOUNTAIN WEST
WEDNESDAY THEN TREK EASTWARD INTO THE CENTRAL ROCKIES WEDNESDAY
NIGHT BEFORE SWINGING ACROSS NEBRASKA AND THE NORTHERN PLAINS
THURSDAY. AT THE SURFACE, AN AREA OF LOW PRESSURE WILL INTENSIFY
AS THE PREVIOUS FEATURE APPROACHES WITH A STALLED OUT FRONT
EXTENDING EASTWARD ACROSS SOUTHERN KANSAS. PATCHY FOG WILL BE
POSSIBLE NORTH OF THIS FRONT WHERE LIGHT WINDS AND AMPLE LOW LEVEL
MOISTURE WILL BE FOUND. THIS FOG IS ONLY EXPECTED TO LAST A COUPLE
OF HOURS AFTER SUNRISE WITH MOSTLY CLEAR SKIES EXPECTED FOR THE
REMAINDER OF THE DAY DUE TO MID LEVELS OF THE ATMOSPHERE BEING
DRY. VERY DRY AIR WILL BE FILTERED IN FROM THE SOUTHWEST SOUTH OF
THIS FRONT LEADING TO A DRYLINE ACROSS FAR SOUTHWESTERN KANSAS. IN
ADDITION, A FEW THUNDERSTORMS COULD FORM AHEAD OF THIS DRYLINE
DURING THE LATE AFTERNOON INTO THE EARLY EVENING. HOWEVER, ANY
CONVECTION THAT DOES FORM WILL QUICKLY MOVE EASTWARD INTO
WICHITA`S CWA. THE AREA OF LOW PRESSURE WILL QUICKLY MOVE EASTWARD
ACROSS KANSAS WEDNESDAY NIGHT WITH A COOLER NORTHWESTERLY WINDS
FELT BEHIND IT. MOISTURE WILL WRAP AROUND THIS SYSTEM BRINGING
SCATTERED SHOWERS ACROSS PORTIONS OF THE PLAINS. HOWEVER, MOST OF
THE LIFT WILL BE NORTH OF THE AREA WITH ONLY A SLIGHT CHANCE OF
SHOWERS ACROSS THE I-70 CORRIDOR EARLY THURSDAY MORNING.
A QUIET PATTERN WILL BE IN PLACE THURSDAY NIGHT THROUGH FRIDAY AS
HIGH PRESSURE BUILDS INTO THE AREA THURSDAY NIGHT THEN TREKS
SOUTHEAST OF THE AREA FRIDAY. AN AREA OF LOW PRESSURE WILL ALSO
DEVELOP ACROSS EASTERN COLORADO FRIDAY DUE TO A WEAK SHORTWAVE
MOVING THROUGH THE NORTHERN ROCKIES. SKIES LOOK TO BE MOSTLY CLEAR
DURING THIS PERIOD WITH WINDS BECOMING SOUTHERLY BY FRIDAY
AFTERNOON.
ATTENTION THEN FOCUSES ON THE WEEKEND AS AN UPPER LEVEL SHORTWAVE
INTENSIFIES ABOVE THE DESERT SOUTHWEST THEN TRACKS EASTWARD ACROSS
THE SOUTHERN ROCKIES AND SOUTHERN PLAINS. A LARGE DOME OF HIGH
PRESSURE WILL BE IN PLACE ACROSS THE EASTERN UNITED STATES AS THIS
FEATURE APPROACHES ALLOWING GULF MOISTURE TO BE PUSHED NORTH INTO
THE PLAINS. A FEW THUNDERSTORMS WILL BE POSSIBLE OVER THE WEEKEND
WITH INCREASED CLOUD COVER. A QUIET PATTERN THEN RETURNS EARLY
NEXT WEEK AS AN UPPER LEVEL RIDGE BUILDS ACROSS THE SOUTHWEST
UNITED STATES.
AS FOR TEMPERATURES, HIGHS WEDNESDAY LOOK TO RANGE FROM THE LOWER
70S NORTH OF THE FRONT TO UPPER 80S ACROSS THE KS/OK BORDER WHERE
THE VERY DRY AIR WILL BE IN PLACE. LOWS WEDNESDAY NIGHT LOOK TO
RANGE FROM AROUND 40 DEGREES ACROSS WEST CENTRAL KANSAS TO LOWER
50S ACROSS SOUTH CENTRAL KANSAS. COOLER TEMPERATURES ARE EXPECTED
BEHIND THE FRONT THURSDAY INTO FRIDAY WITH HIGHS IN THE 60S. LOWS
THURSDAY NIGHT ARE FORECASTED TO DIP INTO THE 30S WITH LOWER 40S
EXPECTED FRIDAY NIGHT. HIGHS REBOUND INTO THE 70S THIS WEEKEND
WITH LOWS IN THE 40S TO LOWER 50S. HIGHS MONDAY THEN LOOK TO BE
AROUND 70 DEGREES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 612 AM CDT TUE APR 7 2015
DENSE FOG WILL BE OBSERVED ACROSS THE DDC AND GCK TERMINALS
THROUGH 14Z BRINGING LIFR CONDITIONS. SKIES THEN BECOME MOSTLY
CLEAR THIS AFTERNOON. WINDS WILL GENERALLY BE FROM THE NORTH THIS
MORNING INTO THE AFTERNOON, SHIFTING TO THE SOUTHEAST THIS
EVENING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 80 49 84 46 / 0 10 10 10
GCK 79 46 81 42 / 0 10 10 10
EHA 83 47 81 43 / 0 10 0 10
LBL 85 46 85 44 / 0 10 0 0
HYS 70 46 69 46 / 10 20 20 20
P28 85 55 88 53 / 10 10 20 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 8 AM CDT /7 AM MDT/ THIS MORNING FOR
KSZ045-046-061>065-075>079.
FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR KSZ061>063-074>078-080-081-084>090.
&&
$$
SHORT TERM...GERARD
LONG TERM...HOVORKA_42
AVIATION...HOVORKA_42
AREA FORECAST DISCUSSION
NWS WICHITA KS
613 AM CDT TUE APR 7 2015
...UPDATED FOR 12Z AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 334 AM CDT TUE APR 7 2015
IN THE UPPER LEVELS...WE CURRENTLY HAVE A STRONG UPPER LOW APPROACHING
NORTHERN CA WITH SW FLOW ALOFT SPREAD OVER THE ROCKIES INTO THE
PLAINS. AT THE SURFACE...LOW PRESSURE IS CENTERED OVER WEST-
CENTRAL KS/FAR EASTERN CO WITH A STATIONARY FRONT STRETCHING FROM
THE LOW PRESSURE ACROSS NORTHEAST KS AND CENTRAL MO. RICH LOW
LEVEL MOISTURE CONTINUES TO STREAM NORTH FROM THE GULF WITH
WIDESPREAD UPPER 60S DEW POINTS ACROSS EAST TX.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 334 AM CDT TUE APR 7 2015
THE UPPER LOW WILL SLOWLY TRACK EAST TODAY AND WILL BE APPROACHING
THE CENTRAL GREAT BASIN TONIGHT. A DRY LINE WILL MIX EAST TODAY
ACROSS WESTERN OK/TX WITH THE SYNOPTIC FRONT TAKING UP POSITION
FROM NE TO SW ACROSS SE KS AND INTO NORTH CENTRAL OK. THE MAIN
QUESTION WILL BE WHETHER STORMS CAN DEVELOP ALONG THESE BOUNDARIES
LATE THIS AFTERNOON/EVENING. THE NAM AND GFS HAVE BOTH BACKED OFF
ON THE AMOUNT OF CONVERGENCE OVER SE KS WITH THE RAP MUCH MORE
AGGRESSIVE IN BREAKING OUT CONVECTION LATE THIS AFTERNOON. CURRENT
THINKING IS THAT THERE IS STILL A CHANCE A STORM OR TWO COULD
DEVELOP LATE THIS AFTERNOON OVER SE KS WITH ANOTHER CHANCE FOR
ELEVATED STORMS AFTER DARK IN THIS SAME LOCATION ASSOCIATED WITH
AN INCREASE IN 850-700MB MOISTURE TRANSPORT. ANY STORM THAT
DEVELOPS EITHER THIS AFTERNOON OR TONIGHT WILL HAVE A GOOD CHANCE
TO BE SEVERE. THE TORNADO THREAT WILL BE CONDITIONAL ON STORMS
BEING ABLE TO DEVELOP IN THE 22-01Z TIME FRAME SO IT COULD STILL
BE ROOTED IN THE BOUNDARY LAYER AND THUS TAKE ADVANTAGE OF THE LOW
LEVEL SHEAR.
SIGNIFICANT SEVERE STORMS STILL LOOK POSSIBLE WED
AFTERNOON/EVENING ACROSS MAINLY SOUTH CENTRAL KS. QUITE
CONSIDERABLE DIFFERENCES HAVE SHOWN UP BETWEEN THE GFS AND NAM.
THE NAM HAS THE STATIONARY FRONT MUCH FURTHER SOUTH COMPARED TO
THE GFS WHICH WOULD LIMIT SEVERE CHANCES OVER MUCH OF CENTRAL KS.
THE NAM DOES HAVE SOME SUPPORT FROM THE 00Z ECMWF. THE MAIN
QUESTION REGARDING STORMS WED AFTERNOON/EVENING ISN`T HOW SEVERE
THEY WILL BE IF THEY DEVELOP...IT IS HOW MANY STORMS ARE ABLE TO
DEVELOP. FEEL THAT WITH SOME SHORTWAVE ENERGY FINALLY KICKING OUT
OF THE ROCKIES...AT LEAST A FEW STORMS WILL DEVELOP WED
AFTERNOON/EVENING...ESPECIALLY NEAR THE TRIPLE POINT WHERE
CONVERGENCE WILL BE MAXIMIZED. WITH 0-6KM SHEAR IN THE 45-55KT
RANGE AND CAPE IN THE 2500-3000J/KG RANGE...ANY STORMS THAT
DEVELOP WILL QUICKLY BECOME SEVERE. STORMS SHOULD BE ABLE TO STAY ISOLATED
AS THEY MOVE OFF THE DRYLINE WITH THE DEEP LAYER SHEAR
PERPENDICULAR TO THE BOUNDARY. THE NAM HAS QUITE A BIT MORE 0-3KM
CAPE COMPARED TO THE GFS BUT FEEL IT MAYBE CLOSER TO REALITY AS IT
SURPRISINGLY LOOKS TO HAVE A SLIGHTLY BETTER HANDLE ON THE LOW
LEVEL MOISTURE.
STORMS WILL TRACK EAST WED NIGHT AND AFFECT AREAS EAST OF I-135.
THE UPPER SHORTWAVE WILL QUICKLY PUSH EAST AND WILL BE OVER
WESTERN IA BY THU EVENING. THIS WILL ALLOW THE FRONT TO QUICKLY
SLIDE EAST WITH ONLY FAR SE KS HAVING A SHOT AT STORMS THU
MORNING. MEANWHILE...CENTRAL KS MAY GET IN ON SOME OF THE WARP
AROUND SHOWERS ASSOCIATED WITH THIS SYSTEM ON THU.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 334 AM CDT TUE APR 7 2015
HIGH PRESSURE IS EXPECTED TO SLIDE OVER THE PLAINS FOR FRI
ALLOWING FOR CLEAR SKIES AND TEMPS CLOSER TO SEASONAL NORMALS. AN
ACTIVE SPLIT FLOW PATTERN LOOKS TO COMMENCE FOR THE WEEKEND AS A
SERIES OF SHORTWAVES MOVE OUT OF THE ROCKIES AND ACROSS THE
PLAINS. THE IMPULSE THAT SHOULD HAVE AN IMPACT ON OUR FORECAST
AREA WILL LIFT OUT OF THE DESERT SW SAT AND INTO CENTRAL KS FOR
SUN WITH A MORE SIGNIFICANT TROUGH SWINGING ACROSS THE PLAINS FOR
MON. AT THIS TIME THE SAT NIGHT-SUN NIGHT TIME FRAME LOOKS TO HAVE
THE BEST CHANCES AT SHOWERS AND STORMS.
LAWSON
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 609 AM CDT TUE APR 7 2015
POOR AVIATION CONDITIONS WILL CONTINUE TO LINGER ACROSS CENTRAL
KANSAS THIS MORNING AS A COLD FRONT SAGS SLOWLY SOUTHWARD...WITH
LOW CLOUDS AND PATCHY DENSE FOG. THE VISIBILITIES/LOW CLOUDS WILL
GRADUALLY IMPROVE LATER THIS MORNING. MEANWHILE THE COLD FRONT
WILL STALL OUT OVER SOUTHERN KANSAS BY THIS EVENING...WITH
ISOLATED SEVERE STORMS POSSIBLE OVER SOUTHEAST KANSAS. THE FRONT
WILL SLOWLY LIFT NORTHWARD AS A WARM FRONT TONIGHT...AND ONCE
AGAIN LOW CLOUDS COULD FILL IN ALONG AND NORTH OF THE FRONT OVER
CENTRAL KANSAS LATE TONIGHT.
JAKUB
&&
.FIRE WEATHER...
ISSUED AT 310 PM CDT MON APR 6 2015
THE MOST CRITICAL FIRE WEATHER DAY THROUGH THIS FORECAST PACKAGE
LOOKS TO BE THURSDAY.
EVEN WITH RICH LOW LEVEL MOISTURE...VERY HIGH FIRE DANGER WILL BE
IN PLACE ACROSS SOUTH CENTRAL AND PARTS OF SE KS WED DUE TO
STRONG SOUTH WINDS. WINDS WILL FLIP AROUND TO THE WEST AND
NORTHWEST ON THU AT SPEEDS IN THE 20-30 MPH RANGE BY AFTERNOON
HOURS. RH`S THU AFTERNOON WILL BE IN THE 30-40% RANGE.
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 83 64 84 55 / 10 10 30 30
HUTCHINSON 80 56 80 51 / 0 10 30 20
NEWTON 83 58 81 53 / 10 10 30 30
ELDORADO 84 65 82 59 / 10 20 30 40
WINFIELD-KWLD 85 65 83 60 / 10 10 30 30
RUSSELL 71 48 70 47 / 10 10 20 20
GREAT BEND 75 50 74 47 / 10 10 20 10
SALINA 75 52 73 50 / 10 10 30 30
MCPHERSON 79 55 77 50 / 10 10 30 30
COFFEYVILLE 83 65 81 65 / 10 20 30 40
CHANUTE 83 65 80 64 / 10 30 30 50
IOLA 83 64 79 63 / 10 30 40 50
PARSONS-KPPF 83 65 81 64 / 10 20 30 50
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1150 AM EDT Tue Apr 7 2015
...Forecast Update...
Issued at 1149 AM EDT Tue Apr 7 2015
The complex of showers and thunderstorms will continue to push east
along the I-64 corridor for the next hour or two. They are looking
less organized but will still be capable of frequent cloud to ground
lightning and brief heavy rainfall.
Focus is now shifting to the west where the previous supercell has
now evolved into a growing linear segment crossing the Mississippi
River near St. Louis. This feature is expected to continue ESE or SE
toward our region through the early afternoon, growing as it does
so. Already seeing good destabilization across west central KY where
some clearing has occurred, and do expect a 1500 - 2500 J/KG
instability axis to setup along and west of I-65 during peak
heating. Some of the southern Indiana counties where this morning`s
complex passed may struggle to get as unstable. Will also note that
0-6 km bulk shear should range between 30-40 knots, sufficient for
continued organization. Forecast sounding are quite impressive if
they verify and would suggest a severe wind and hail threat with the
strongest storms. In collaboration with the Storm Prediction Center,
mention of an upgrade to a slight risk is a possibility across
western portions of our CWA this afternoon. Right now the best
timing for the CWA looks to be between 3 PM EDT and 9 PM EDT.
Do want to mention that another round of heavy rain will accompany
the potential severe threat with this next round of convection.
Depending on where heaviest rain falls, more hydro products may be
needed.
Previous Update...
Issued at 919 AM EDT Tue Apr 7 2015
Storms will wind down along the I-64 corridor through the late
morning hours. However, will have to keep an eye on the stronger
cluster currently over southern Indiana as it moves ESE toward the
Kentucky Bluegrass region. Very intense rainfall has left 2 to 3
inches in a short amount of time across small portions of southern
Indiana and will keep the Flash Flood Warning going across
Orange/Washington counties for the time being. Have upped pops and
QPF to account for this cluster. Hail will also be possible with
this storm.
Focus will then shift to this afternoon and evening as another round
of storms will be possible. Looking upstream, an impressive
supercell is tracking ESE along I-70 and the warm front toward St.
Louis. This feature is expected to turn more SE along the
instability gradient through the late morning and early afternoon,
and grow into a more linear complex. Do expect to get some partial
clearing which will aid an already destabilizing atmosphere. SREF
probabilities of greater than 1000 J/KG of CAPE this afternoon are
likely along and west of I-65. 0-6 km shear values between 30 and 40
knots this afternoon would also support organization. Will have to
watch how things progress through the late morning as there is some
concern for strong to severe storms this afternoon and evening.
The 06z NAM and HRRR are handling the current situation pretty well.
However the NAM is a bit too far north and a couple hours slow. Did
the afternoon forecast based off this solution with adjustments for
timing placement. Adjusted QPF upward as well in anticipation of the
afternoon storms.
.SHORT TERM (Now through Wednesday)...
Issued at 257 AM EDT Tue Apr 7 2015
The GFS, 4km NAM, and, to a lesser extent, SPC SREF, have a good
handle on an area of showers and embedded thunderstorms moving from
southeast Illinois into the lower and middle Ohio Valley at 07Z
this morning. The storms are ahead of an upper level disturbance
coming in from the lower and middle Mississippi Valley. This
convective complex will continue to spread eastward this morning
along and a few counties either side of the I-64 corridor. Though
the showers and storms will mostly be garden variety, a few gusts of
wind or instances of small hail in the strongest cores can`t be
entirely ruled out.
The morning showers and storms will have moved off to the east by
early afternoon. This afternoon another weak upper wave will come
in from the west. Though some stabilization will occur over
southern Indiana and northern Kentucky from the morning rain,
additional scattered shower and thunderstorm development will be
possible, albeit with less coverage than what we see this morning.
Again, a few strong storms will be possible.
With plenty of moisture available, locally heavy downpours will be
possible with the thunderstorms. The cells should be progressive,
but there will be some training this morning in southern Indiana
and north central Kentucky.
Decided to drop max temps a few degrees in the north where more rain
and clouds will prevail through the morning hours, but still have
70s everywhere for highs this afternoon.
After a lull this evening, more shower and thunderstorm development
will be possible late tonight as the next weak upper wave comes in
from the west after midnight. Low temperatures will be in the lower
and middle 60s.
The relatively low confidence forecast today and tonight becomes
even lower on Wednesday. We will remain in the same warm, juicy air
mass as today, south of a stationary surface front from Illinois to
Ohio. The late night showers/storms tonight will likely persist
into Wednesday morning, with redevelopment possible Wednesday
afternoon especially near any leftover convective boundaries from
the morning activity. Highs should be in the middle and upper
70s...maybe an 80 degree reading if we can get enough sunshine in
the afternoon.
.LONG TERM (Wednesday Night through Monday)...
Issued at 235 AM EDT Tue Apr 7 2015
The focus in the long term period is on thunderstorm chances/timing
Wednesday night through Friday.
The upper level pattern Wednesday night is expected to feature a
digging trough from the Rockies into the central Plains with
downstream ridging extending from the Gulf Coast through the
southern Great Lakes region. At the surface, a warm and moist air
mass characterized by dewpoints in the 60s will be in place thanks
to a developing surface low to our west. Stronger southerly flow
should make for a mild night with lows only falling into the mid
60s.
The focus for thunderstorm initiation Wednesday night is favored to
our west where the strengthening low-level jet impinges on an
east-west boundary across Illinois. These storms could then take an
east/southeast track across portions of the area. Strength/severity
a bit more uncertain as elevated instability wanes considerably
and effective shear is not as impressive but a few elevated stronger
storms would be possible. Kept POPs in the 30-50 percent range,
tapered highest to lowest from southern Indiana to southern Kentucky
respectively.
The main upper level trough will advance eastward Thursday as the
surface low deepens/lifts to Wisconsin by Thursday night. 07.00z
guidance remained overall similar to earlier runs in its
progression, bringing the cold front through the local area late
Thursday night into Friday morning. Scattered showers and
thunderstorms are possible ahead of the main system though coverage
isn`t expected to be very high. Decaying strong thunderstorms look
to be approaching our western borders during the late evening, and
if enough elevated instability remains present, a marginal wind
threat exists. Overall, the system looks fairly progressive,
limiting the training heavy rainfall threat as well.
Ahead of the front, a very warm air mass will be in place. Depending
on how cloud cover fares, we`ll be approaching 80 degrees in most
spots Thursday. A mild night would then set up with lows in the mid
60s to near 70 degrees.
Friday looks to be our transition day as the front sweeps across the
area. Will keep chance POPs in the morning to early afternoon hours,
especially east of I-65 before clearing conditions work in for the
evening. Seasonable, pleasant and mostly sunny conditions thanks to
surface high pressure expected Saturday into the first part of
Sunday. A model consensus approach gives highs in the mid to upper
60s Saturday and upper 60s to low 70s Sunday.
Increasing moisture and southerly return flow sets up Sunday night
into early next week as the surface high moves to our east. A slow
ramp up in POPs, still chance, will be advertised as deterministic
models show another system lifting through the central Plains to
lower Great Lakes. Seasonable to above seasonable temperatures look
reasonable at this time.
&&
.AVIATION (12Z TAF Update)...
Updated at 636 AM EDT Tue Apr 7 2015
Showers should be common through the morning hours, especially at
LEX and SDF, with some embedded thunder as well. Ceilings will be
highly variable, but should prevail MVFR below fuel mins. Expect
drier conditions this afternoon and tonight (though scattered
showers and storms will still be possible). Ceilings should
gradually improve today as the wave that is sparking this morning`s
convection moves off to the east.
BWG could see a few wind gusts into the teens this afternoon outside
of convection.
Another wave of convection may come in from the northwest late
tonight into Wednesday morning, though forecast confidence is not
high that far out in this weather regime.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........BJS
Short Term.....13
Long Term......ZT
Aviation.......13
AREA FORECAST DISCUSSION
NWS JACKSON KY
1135 AM EDT TUE APR 7 2015
.UPDATE...
ISSUED AT 1135 AM EDT TUE APR 7 2015
THUNDERSTORM COMPLEX WHICH RESULTED IN A FEW FLOODING REPORTS IN
OUR SOUTHERN COUNTIES IS EXITING IN TN AND VA. OTHER THUNDERSTORMS
IN THE LMK AREA WERE HEADING TOWARD OUR NORTHERN COUNTIES...BUT
WERE WEAKENING. HAVE ADJUSTED NEAR TERM POPS FOR THE OBSERVED
RADAR TRENDS. WITH A MOIST AIR MASS...WARM AIR ADVECTION...A
FRONTAL BOUNDARY JUST TO OUR NORTH...NO SIGNIFICANT CAP...AND WEAK
IMPULSES PASSING THROUGH...REDEVELOPMENT/INTENSIFICATION WILL BE A
POSSIBILITY AS SOME LIMITED DESTABILIZATION OCCURS THIS AFTERNOON.
CONFIDENCE IN TIMING AND LOCATION IS LOW. HAVE LEANED TOWARD THE
HRRR SOLUTION THIS AFTERNOON INTO TONIGHT...BUT KEPT THE FORECAST
FAIRLY GENERALIZED.
UPDATE ISSUED AT 800 AM EDT TUE APR 7 2015
DID A QUICK UPDATE TO THE GRIDS TO REFLECT THE LATEST RADAR TRENDS
WITH THE SWATH OF SHOWERS AND EMBEDDED THUNDERSTORMS MOVING
THROUGH THE CWA. ALSO FINE TUNED THE TEMPS AND TD FOR THE LATEST
OBS AND TRENDS. THE UPDATED GRIDS HAVE BEEN SENT TO THE NDFD AND
WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 340 AM EDT TUE APR 7 2015
06Z SFC ANALYSIS SHOWS LOW PRESSURE OVER THE CENTRAL PLAINS WITH A
WARM FRONT SLUNG EAST...RUNNING INTO THE OHIO VALLEY BEFORE
BECOMING A STATIONARY BOUNDARY JUST NORTH OF EASTERN KENTUCKY.
THIS PLACES THE CWA IN A WARM AND MOIST ENVIRONMENT AS SOUTH WINDS
SUPPORT PWS APPROACHING 1.5 INCHES. JUST NOW A FEW SHOWERS ARE
STARTING TO POP OVER THE SOUTHERN PARTS OF THE AREA AFTER A
RELATIVELY QUIET EVENING AND START TO THE NIGHT. ADDITIONAL
CONVECTION TO THE WEST IS PUSHING EAST JUST SOUTH OF THE WARM
FRONT...CURRENTLY MOVING THROUGH NORTHWESTERN KENTUCKY AND
SOUTHERN ILLINOIS/INDIANA. UNDER MOSTLY CLOUDY SKIES OVERNIGHT...
MOST OF EASTERN KENTUCKY IS SEEING TEMPERATURES FROM 55 TO 60
DEGREES WITH SOME EASTERN VALLEYS SLIGHTLY COOLER AND WARMER
CONDITIONS IN THE FAR SOUTHWEST. DEW POINTS...MEANWHILE...HAVE
COME UP INTO THE 50S FOR THE AREA...A DRAMATIC REVERSAL OF THIS
PAST WEEKEND/S DRYNESS.
THE MODELS ARE IN FAIRLY GOOD AGREEMENT ALOFT THROUGH THE SHORT
TERM AS A SERIES OF WEAK TO MODERATE WAVES PASS THROUGH THE OHIO
VALLEY IN BROAD...SLIGHTLY SOUTHWEST...FLOW ON THE NORTHERN
FRINGE OF THE FLAT SOUTHEAST RIDGE. EACH MODEL HAS A SLIGHTLY
DIFFERENT HANDLE ON THE TIMING AND TRACK OF THESE WAVES LOWERING
CONFIDENCE IN ANY PARTICULAR SOLUTION. NEVERTHELESS...THE ENERGY
WILL BE THERE...ALONG WITH PLENTY OF FUEL IN THE FORM OF HEAT AND
HUMIDITY...FOR CONVECTIVE DEVELOPMENT BASED MORE ON THESE MID
LEVEL RIPPLES THAN STRICTLY THE DIURNAL CYCLE. GIVEN THE SMALL
NATURE OF THE FEATURES THAT WILL DRIVE THE CONVECTION OVER THE
NEXT COUPLE OF DAYS HAVE RELIED MORE CLOSELY ON THE HIGHER
RESOLUTION HRRR AND NAM12 FOR THE WEATHER DETAILS.
SENSIBLE WEATHER WILL FEATURE AN UNSEASONABLY WARM AND HUMID
PERIOD WITH OCCASIONAL ROUNDS OF SHOWERS AND THUNDERSTORMS
EXPECTED DUE TO EASTERN KENTUCKY/S POSITION SOUTH OF A STALLED
FRONTAL BOUNDARY TO THE NORTH AND IMPULSES PASSING THROUGH FROM
ALOFT. THE FIRST OF THESE WILL PASS THIS MORNING WITH A ROUND OF
CONVECTION EXPECTED FOLLOWED BY A POTENTIAL FOR ANOTHER LATE THIS
AFTERNOON AND INTO THE EVENING. THE NAM12 WOULD THEN HAVE A LULL
UNTIL DAYTIME WEDNESDAY WHEN ANOTHER WAVE IS EXPECTED TO DEVELOP
AND PASS OVER THE STATE. SEVERE WEATHER WILL BE A POSSIBILITY
TODAY WITH EITHER OF THESE CLUSTERS DEPENDING ON UPSCALE GROWTH
AND...FOR THE LATTER...SFC HEATING BETWEEN SYSTEMS. GIVEN THE
RELATIVELY HIGH PWS...HEAVY RAIN WILL BE A POSSIBILITY AS WELL AND
MAY PRIME THE AREA FOR LOCALIZED FLOOD CONCERNS BEFORE THE FRONTAL
STRUCTURE MOVES OUT OF THE REGION AT WEEK/S END. WILL HIGHLIGHT
BOTH THE SVR AND HEAVY RAIN CONCERNS IN THE FORTHCOMING HWO.
USED THE SHORTBLEND COMPOSITE MODEL AS A STARTING POINT FOR THE
WINDS/T/TD GRIDS THROUGH THE FIRST 18-24 HOURS AND THE SUPERBLEND
THEREAFTER. DID MAKE SOME MINOR ADJUSTMENTS BASED ON TERRAIN FOR
TONIGHT/S TEMPERATURES. AS FOR POPS...ENDED UP CLOSEST TO THE MET
VALUES TODAY AND TONIGHT...BUT HIGHER FOR MIDDAY WEDNESDAY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 335 AM EDT TUE APR 7 2015
MULTIPLE WAVES WILL CONTINUE TO RIDE UP AND ALONG A RIDGING PATTERN
ACROSS THE EASTERN CONUS THROUGH THE SHORT TERM AND TO START OUT THE
EXTENDED PORTION OF THE FORECAST. MEANWHILE A STRONG SHORTWAVE OVER
THE ROCKIES WILL BEGIN TO SHIFT EASTWARD BY 0Z THURSDAY...CREATING
LONGWAVE TROUGHING OVER THE WESTERN CONUS. EXPECT THIS SHORTWAVE TO
CONTINUE ON ITS TREK EAST AND NORTHEASTWARD THROUGH THE DAY THURSDAY
AND INTO THE DAY FRIDAY...WITH DECREASING HEIGHTS EXPECTED ACROSS
THE OHIO RIVER VALLEY DURING THIS TIME.
AT THE SURFACE...KY WILL FIND ITSELF UNDER THE INFLUENCE OF A
STALLED WARM FRONT WEDNESDAY NIGHT INTO THURSDAY MORNING...WHICH
WILL LIKELY BE POSITIONED ACROSS THE NORTHERN PORTION OF THE CWA.
THIS WILL RESULT IN CONTINUED SHOWERS AND THUNDERSTORMS...ESPECIALLY
ACROSS THE NORTHERN HALF OF THE STATE. TO OUR EAST...A SURFACE LOW
WILL CONTINUE TO DEVELOP BELOW AND JUST AHEAD OF THE ABOVE MENTIONED
SHORTWAVE...AND FOLLOW ITS TRACK NORTHEASTWARD THROUGH THE DAY
THURSDAY. BY 0Z FRIDAY...THE WARM FRONT WILL SHIFT EAST AND ENABLE A
STRONG COLD FRONT...CONNECTED TO THIS LOW PRESSURE SYSTEM...TO PUSH
FROM WEST TO EAST ACROSS KY. GIVEN THE LATEST GFS FORECAST...THE
BOUNDARY SHOULD ENTER INTO EASTERN KY SOMETIME FRIDAY
AFTERNOON...ENHANCING SHOWER AND THUNDERSTORM ACTIVITY THROUGH THE
MORNING JUST AHEAD OF THE FRONT...AND EXIT EAST OF THE STATE BETWEEN
21Z FRIDAY AND 0Z SATURDAY. ONCE IT DOES...KY WILL BE IN A MORE
ZONAL UPPER LEVEL FLOW WITH SURFACE HIGH PRESSURE BUILDING ACROSS
THE STATE. SURFACE WINDS WILL ONCE AGAIN BECOME MORE
NORTHERLY...CAUSING TEMPERATURES TO DROP BACK INTO THE 40S OVERNIGHT
FRIDAY NIGHT/SATURDAY MORNING...AND IN THE MID 60S BY SATURDAY
AFTERNOON.
EXPECT THIS HIGH PRESSURE TO KEEP DRY WEATHER IN PLAY THROUGH MUCH
OF THE WEEKEND...WITH TEMPERATURES EXPECTED TO REBOUND BACK INTO THE
LOW 70S BY MONDAY. BY THIS TIME...A LOW PRESSURE SYSTEM OVER THE
SOUTHERN PLAINS WILL MOVE NE ONCE MORE AND PUSH A WARM FRONT
NORTHWARD INTO THE REGION...ALLOWING UNSTABLE WARM GULF MOISTURE TO
FLOW BACK INTO THE CWA AND ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS TO DEVELOP LATE SUNDAY AND SUNDAY NIGHT. THIS WILL BE
ENHANCED AS THE FOLLOWING COLD FRONT BEGINS FROM WEST TO EAST ACROSS
THE STATE ONCE MORE DURING THE DAY MONDAY AND MONDAY NIGHT. EXACT
TIMING OF THIS FRONTAL PASSAGE...AS WELL AS THE ONSET AND STRENGTH OF
THE PRECIPITATION ARE STILL FAR ENOUGH OUT IN THE FORECAST THAT
RELYING ON A MODEL BLEND WAS THE METHOD OF CHOICE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 815 AM EDT TUE APR 7 2015
THE SHOWERS AND STORMS MOVED INTO THE AREA ON TRACK WITH THE
EARLIER FORECAST WITH MVFR TO IFR CIGS. THESE WILL BE THE RULE
FOR MOST OF THE AREA THROUGH THE TAF PERIOD EVEN ONCE THIS
INITIAL PASSES THROUGH BY MID MORNING. ANOTHER IMPULSE IS EXPECTED
THIS EVENING WITH ADDITIONAL LOW CIGS AND SHOWERS/STORMS. IN THE
HEAVIER CONVECTION...MVFR VIS WILL BE A GOOD BET WITH OCCASIONAL
IFR VIS OR CIGS IN STORMS. THROUGH THE TAF PERIOD...WINDS WILL
GENERALLY BE FROM THE SOUTH AT 5 TO 10 KTS...EXCEPT FOR HIGHER
GUSTS IN STORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
920 AM EDT Tue Apr 7 2015
...Forecast Update...
Issued at 919 AM EDT Tue Apr 7 2015
Storms will wind down along the I-64 corridor through the late
morning hours. However, will have to keep an eye on the stronger
cluster currently over southern Indiana as it moves ESE toward the
Kentucky Bluegrass region. Very intense rainfall has left 2 to 3
inches in a short amount of time across small portions of southern
Indiana and will keep the Flash Flood Warning going across
Orange/Washington counties for the time being. Have upped pops and
QPF to account for this cluster. Hail will also be possible with
this storm.
Focus will then shift to this afternoon and evening as another round
of storms will be possible. Looking upstream, an impressive
supercell is tracking ESE along I-70 and the warm front toward St.
Louis. This feature is expected to turn more SE along the
instability gradient through the late morning and early afternoon,
and grow into a more linear complex. Do expect to get some partial
clearing which will aid an already destabilizing atmosphere. SREF
probabilities of greater than 1000 J/KG of CAPE this afternoon are
likely along and west of I-65. 0-6 km shear values between 30 and 40
knots this afternoon would also support organization. Will have to
watch how things progress through the late morning as there is some
concern for strong to severe storms this afternoon and evening.
The 06z NAM and HRRR are handling the current situation pretty well.
However the NAM is a bit too far north and a couple hours slow. Did
the afternoon forecast based off this solution with adjustments for
timing placement. Adjusted QPF upward as well in anticipation of the
afternoon storms.
.SHORT TERM (Now through Wednesday)...
Issued at 257 AM EDT Tue Apr 7 2015
The GFS, 4km NAM, and, to a lesser extent, SPC SREF, have a good
handle on an area of showers and embedded thunderstorms moving from
southeast Illinois into the lower and middle Ohio Valley at 07Z
this morning. The storms are ahead of an upper level disturbance
coming in from the lower and middle Mississippi Valley. This
convective complex will continue to spread eastward this morning
along and a few counties either side of the I-64 corridor. Though
the showers and storms will mostly be garden variety, a few gusts of
wind or instances of small hail in the strongest cores can`t be
entirely ruled out.
The morning showers and storms will have moved off to the east by
early afternoon. This afternoon another weak upper wave will come
in from the west. Though some stabilization will occur over
southern Indiana and northern Kentucky from the morning rain,
additional scattered shower and thunderstorm development will be
possible, albeit with less coverage than what we see this morning.
Again, a few strong storms will be possible.
With plenty of moisture available, locally heavy downpours will be
possible with the thunderstorms. The cells should be progressive,
but there will be some training this morning in southern Indiana
and north central Kentucky.
Decided to drop max temps a few degrees in the north where more rain
and clouds will prevail through the morning hours, but still have
70s everywhere for highs this afternoon.
After a lull this evening, more shower and thunderstorm development
will be possible late tonight as the next weak upper wave comes in
from the west after midnight. Low temperatures will be in the lower
and middle 60s.
The relatively low confidence forecast today and tonight becomes
even lower on Wednesday. We will remain in the same warm, juicy air
mass as today, south of a stationary surface front from Illinois to
Ohio. The late night showers/storms tonight will likely persist
into Wednesday morning, with redevelopment possible Wednesday
afternoon especially near any leftover convective boundaries from
the morning activity. Highs should be in the middle and upper
70s...maybe an 80 degree reading if we can get enough sunshine in
the afternoon.
.LONG TERM (Wednesday Night through Monday)...
Issued at 235 AM EDT Tue Apr 7 2015
The focus in the long term period is on thunderstorm chances/timing
Wednesday night through Friday.
The upper level pattern Wednesday night is expected to feature a
digging trough from the Rockies into the central Plains with
downstream ridging extending from the Gulf Coast through the
southern Great Lakes region. At the surface, a warm and moist air
mass characterized by dewpoints in the 60s will be in place thanks
to a developing surface low to our west. Stronger southerly flow
should make for a mild night with lows only falling into the mid
60s.
The focus for thunderstorm initiation Wednesday night is favored to
our west where the strengthening low-level jet impinges on an
east-west boundary across Illinois. These storms could then take an
east/southeast track across portions of the area. Strength/severity
a bit more uncertain as elevated instability wanes considerably
and effective shear is not as impressive but a few elevated stronger
storms would be possible. Kept POPs in the 30-50 percent range,
tapered highest to lowest from southern Indiana to southern Kentucky
respectively.
The main upper level trough will advance eastward Thursday as the
surface low deepens/lifts to Wisconsin by Thursday night. 07.00z
guidance remained overall similar to earlier runs in its
progression, bringing the cold front through the local area late
Thursday night into Friday morning. Scattered showers and
thunderstorms are possible ahead of the main system though coverage
isn`t expected to be very high. Decaying strong thunderstorms look
to be approaching our western borders during the late evening, and
if enough elevated instability remains present, a marginal wind
threat exists. Overall, the system looks fairly progressive,
limiting the training heavy rainfall threat as well.
Ahead of the front, a very warm air mass will be in place. Depending
on how cloud cover fares, we`ll be approaching 80 degrees in most
spots Thursday. A mild night would then set up with lows in the mid
60s to near 70 degrees.
Friday looks to be our transition day as the front sweeps across the
area. Will keep chance POPs in the morning to early afternoon hours,
especially east of I-65 before clearing conditions work in for the
evening. Seasonable, pleasant and mostly sunny conditions thanks to
surface high pressure expected Saturday into the first part of
Sunday. A model consensus approach gives highs in the mid to upper
60s Saturday and upper 60s to low 70s Sunday.
Increasing moisture and southerly return flow sets up Sunday night
into early next week as the surface high moves to our east. A slow
ramp up in POPs, still chance, will be advertised as deterministic
models show another system lifting through the central Plains to
lower Great Lakes. Seasonable to above seasonable temperatures look
reasonable at this time.
&&
.AVIATION (12Z TAF Update)...
Updated at 636 AM EDT Tue Apr 7 2015
Showers should be common through the morning hours, especially at
LEX and SDF, with some embedded thunder as well. Ceilings will be
highly variable, but should prevail MVFR below fuel mins. Expect
drier conditions this afternoon and tonight (though scattered
showers and storms will still be possible). Ceilings should
gradually improve today as the wave that is sparking this morning`s
convection moves off to the east.
BWG could see a few wind gusts into the teens this afternoon outside
of convection.
Another wave of convection may come in from the northwest late
tonight into Wednesday morning, though forecast confidence is not
high that far out in this weather regime.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........BJS
Short Term.....13
Long Term......ZT
Aviation.......13
AREA FORECAST DISCUSSION
NWS JACKSON KY
815 AM EDT TUE APR 7 2015
.UPDATE...
ISSUED AT 800 AM EDT TUE APR 7 2015
DID A QUICK UPDATE TO THE GRIDS TO REFLECT THE LATEST RADAR TRENDS
WITH THE SWATH OF SHOWERS AND EMBEDDED THUNDERSTORMS MOVING
THROUGH THE CWA. ALSO FINE TUNED THE TEMPS AND TD FOR THE LATEST
OBS AND TRENDS. THE UPDATED GRIDS HAVE BEEN SENT TO THE NDFD AND
WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 340 AM EDT TUE APR 7 2015
06Z SFC ANALYSIS SHOWS LOW PRESSURE OVER THE CENTRAL PLAINS WITH A
WARM FRONT SLUNG EAST...RUNNING INTO THE OHIO VALLEY BEFORE
BECOMING A STATIONARY BOUNDARY JUST NORTH OF EASTERN KENTUCKY.
THIS PLACES THE CWA IN A WARM AND MOIST ENVIRONMENT AS SOUTH WINDS
SUPPORT PWS APPROACHING 1.5 INCHES. JUST NOW A FEW SHOWERS ARE
STARTING TO POP OVER THE SOUTHERN PARTS OF THE AREA AFTER A
RELATIVELY QUIET EVENING AND START TO THE NIGHT. ADDITIONAL
CONVECTION TO THE WEST IS PUSHING EAST JUST SOUTH OF THE WARM
FRONT...CURRENTLY MOVING THROUGH NORTHWESTERN KENTUCKY AND
SOUTHERN ILLINOIS/INDIANA. UNDER MOSTLY CLOUDY SKIES OVERNIGHT...
MOST OF EASTERN KENTUCKY IS SEEING TEMPERATURES FROM 55 TO 60
DEGREES WITH SOME EASTERN VALLEYS SLIGHTLY COOLER AND WARMER
CONDITIONS IN THE FAR SOUTHWEST. DEWPOINTS...MEANWHILE...HAVE
COME UP INTO THE 50S FOR THE AREA...A DRAMATIC REVERSAL OF THIS
PAST WEEKEND/S DRYNESS.
THE MODELS ARE IN FAIRLY GOOD AGREEMENT ALOFT THROUGH THE SHORT
TERM AS A SERIES OF WEAK TO MODERATE WAVES PASS THROUGH THE OHIO
VALLEY IN BROAD...SLIGHTLY SOUTHWEST...FLOW ON THE NORTHERN
FRINGE OF THE FLAT SOUTHEAST RIDGE. EACH MODEL HAS A SLIGHTLY
DIFFERENT HANDLE ON THE TIMING AND TRACK OF THESE WAVES LOWERING
CONFIDENCE IN ANY PARTICULAR SOLUTION. NEVERTHELESS...THE ENERGY
WILL BE THERE...ALONG WITH PLENTY OF FUEL IN THE FORM OF HEAT AND
HUMIDITY...FOR CONVECTIVE DEVELOPMENT BASED MORE ON THESE MID
LEVEL RIPPLES THAN STRICTLY THE DIURNAL CYCLE. GIVEN THE SMALL
NATURE OF THE FEATURES THAT WILL DRIVE THE CONVECTION OVER THE
NEXT COUPLE OF DAYS HAVE RELIED MORE CLOSELY ON THE HIGHER
RESOLUTION HRRR AND NAM12 FOR THE WEATHER DETAILS.
SENSIBLE WEATHER WILL FEATURE AN UNSEASONABLY WARM AND HUMID
PERIOD WITH OCCASIONAL ROUNDS OF SHOWERS AND THUNDERSTORMS
EXPECTED DUE TO EASTERN KENTUCKY/S POSITION SOUTH OF A STALLED
FRONTAL BOUNDARY TO THE NORTH AND IMPULSES PASSING THROUGH FROM
ALOFT. THE FIRST OF THESE WILL PASS THIS MORNING WITH A ROUND OF
CONVECTION EXPECTED FOLLOWED BY A POTENTIAL FOR ANOTHER LATE THIS
AFTERNOON AND INTO THE EVENING. THE NAM12 WOULD THEN HAVE A LULL
UNTIL DAYTIME WEDNESDAY WHEN ANOTHER WAVE IS EXPECTED TO DEVELOP
AND PASS OVER THE STATE. SEVERE WEATHER WILL BE A POSSIBILITY
TODAY WITH EITHER OF THESE CLUSTERS DEPENDING ON UPSCALE GROWTH
AND...FOR THE LATTER...SFC HEATING BETWEEN SYSTEMS. GIVEN THE
RELATIVELY HIGH PWS...HEAVY RAIN WILL BE A POSSIBILITY AS WELL AND
MAY PRIME THE AREA FOR LOCALIZED FLOOD CONCERNS BEFORE THE FRONTAL
STRUCTURE MOVES OUT OF THE REGION AT WEEK/S END. WILL HIGHLIGHT
BOTH THE SVR AND HEAVY RAIN CONCERNS IN THE FORTHCOMING HWO.
USED THE SHORTBLEND COMPOSITE MODEL AS A STARTING POINT FOR THE
WINDS/T/TD GRIDS THROUGH THE FIRST 18-24 HOURS AND THE SUPERBLEND
THEREAFTER. DID MAKE SOME MINOR ADJUSTMENTS BASED ON TERRAIN FOR
TONIGHT/S TEMPERATURES. AS FOR POPS...ENDED UP CLOSEST TO THE MET
VALUES TODAY AND TONIGHT...BUT HIGHER FOR MIDDAY WEDNESDAY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 335 AM EDT TUE APR 7 2015
MULTIPLE WAVES WILL CONTINUE TO RIDE UP AND ALONG A RIDGING PATTERN
ACROSS THE EASTERN CONUS THROUGH THE SHORT TERM AND TO START OUT THE
EXTENDED PORTION OF THE FORECAST. MEANWHILE A STRONG SHORTWAVE OVER
THE ROCKIES WILL BEGIN TO SHIFT EASTWARD BY 0Z THURSDAY...CREATING
LONGWAVE TROUGHING OVER THE WESTERN CONUS. EXPECT THIS SHORTWAVE TO
CONTINUE ON ITS TREK EAST AND NORTHEASTWARD THROUGH THE DAY THURSDAY
AND INTO THE DAY FRIDAY...WITH DECREASING HEIGHTS EXPECTED ACROSS
THE OHIO RIVER VALLEY DURING THIS TIME.
AT THE SURFACE...KY WILL FIND ITSELF UNDER THE INFLUENCE OF A
STALLED WARM FRONT WEDNESDAY NIGHT INTO THURSDAY MORNING...WHICH
WILL LIKELY BE POSITIONED ACROSS THE NORTHERN PORTION OF THE CWA.
THIS WILL RESULT IN CONTINUED SHOWERS AND THUNDERSTORMS...ESPECIALLY
ACROSS THE NORTHERN HALF OF THE STATE. TO OUR EAST...A SURFACE LOW
WILL CONTINUE TO DEVELOP BELOW AND JUST AHEAD OF THE ABOVE MENTIONED
SHORTWAVE...AND FOLLOW ITS TRACK NORTHEASTWARD THROUGH THE DAY
THURSDAY. BY 0Z FRIDAY...THE WARM FRONT WILL SHIFT EAST AND ENABLE A
STRONG COLD FRONT...CONNECTED TO THIS LOW PRESSURE SYSTEM...TO PUSH
FROM WEST TO EAST ACROSS KY. GIVEN THE LATEST GFS FORECAST...THE
BOUNDARY SHOULD ENTER INTO EASTERN KY SOMETIME FRIDAY
AFTERNOON...ENHANCING SHOWER AND THUNDERSTORM ACTIVITY THROUGH THE
MORNING JUST AHEAD OF THE FRONT...AND EXIT EAST OF THE STATE BETWEEN
21Z FRIDAY AND 0Z SATURDAY. ONCE IT DOES...KY WILL BE IN A MORE
ZONAL UPPER LEVEL FLOW WITH SURFACE HIGH PRESSURE BUILDING ACROSS
THE STATE. SURFACE WINDS WILL ONCE AGAIN BECOME MORE
NORTHERLY...CAUSING TEMPERATURES TO DROP BACK INTO THE 40S OVERNIGHT
FRIDAY NIGHT/SATURDAY MORNING...AND IN THE MID 60S BY SATURDAY
AFTERNOON.
EXPECT THIS HIGH PRESSURE TO KEEP DRY WEATHER IN PLAY THROUGH MUCH
OF THE WEEKEND...WITH TEMPERATURES EXPECTED TO REBOUND BACK INTO THE
LOW 70S BY MONDAY. BY THIS TIME...A LOW PRESSURE SYSTEM OVER THE
SOUTHERN PLAINS WILL MOVE NE ONCE MORE AND PUSH A WARM FRONT
NORTHWARD INTO THE REGION...ALLOWING UNSTABLE WARM GULF MOISTURE TO
FLOW BACK INTO THE CWA AND ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS TO DEVELOP LATE SUNDAY AND SUNDAY NIGHT. THIS WILL BE
ENHANCED AS THE FOLLOWING COLD FRONT BEGINS FROM WEST TO EAST ACROSS
THE STATE ONCE MORE DURING THE DAY MONDAY AND MONDAY NIGHT. EXACT
TIMING OF THIS FRONTAL PASSAGE...AS WELL AS THE ONSET AND STRENGTH OF
THE PRECIPITATION ARE STILL FAR ENOUGH OUT IN THE FORECAST THAT
RELYING ON A MODEL BLEND WAS THE METHOD OF CHOICE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 815 AM EDT TUE APR 7 2015
THE SHOWERS AND STORMS MOVED INTO THE AREA ON TRACK WITH THE
EARLIER FORECAST WITH MVFR TO IFR CIGS. THESE WILL BE THE RULE
FOR MOST OF THE AREA THROUGH THE TAF PERIOD EVEN ONCE THIS
INITIAL PASSES THROUGH BY MID MORNING. ANOTHER IMPULSE IS EXPECTED
THIS EVENING WITH ADDITIONAL LOW CIGS AND SHOWERS/STORMS. IN THE
HEAVIER CONVECTION...MVFR VIS WILL BE A GOOD BET WITH OCCASIONAL
IFR VIS OR CIGS IN STORMS. THROUGH THE TAF PERIOD...WINDS WILL
GENERALLY BE FROM THE SOUTH AT 5 TO 10 KTS...EXCEPT FOR HIGHER
GUSTS IN STORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1142 AM EDT TUE APR 7 2015
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 329 AM EDT TUE APR 7 2015
THE AREA WILL SEE A RELATIVELY WET PERIOD THROUGH MOST OF THE REST
OF THIS WEEK. A STALLED OUT FRONTAL SYSTEM WILL REMAIN IN THE
REGION. THE AREA WILL BE ON THE COOL NORTH SIDE OF THIS FRONT
THROUGH WEDNESDAY. ROUNDS OF SHOWERS AND EVENTUALLY STORMS CAN BE
EXPECTED. THE FRONT WILL LIFT NORTH OF THE AREA ON THURSDAY AND
BRING WARMER AIR INTO THE AREA. STORMS WILL BECOME MORE LIKELY ON
THURSDAY WITH A THREAT FOR SOME SEVERE WEATHER POSSIBLE DOWN SOUTH.
CONDITIONS WILL QUIET DOWN THEN FOR THE END OF THE WORK WEEK AND
NEXT WEEKEND AS THE ENTIRE FRONTAL SYSTEM PUSHES OUT OF THE AREA.
&&
.UPDATE...
ISSUED AT 1142 AM EDT TUE APR 7 2015
BEST COVERAGE OF SCATTERED RAIN SHOWERS THIS AFTERNOON SHOULD BE
SOUTH OF I-96 CLOSER TO THE H8 BAROCLINIC ZONE. LATEST HRRR IS
FAVORING THE AREA EAST AND SOUTH OF A LINE FROM AZO TO LAN.
FARTHER NORTH AND WEST... MAINLY ISOLATED COVERAGE OF SHOWERS AT
BEST. H5 PROGS SHOW SEVERAL VORTICITY MAXIMA EMBEDDED IN ZONAL
FLOW ALOFT SO AM RELUCTANT TO GO COMPLETELY DRY IN THE NRN CWFA
AFTER 18Z. TEMPS WILL STRUGGLE TO GET OUT OF THE 40S THIS AFTEROON
WITH CLOUDS AND BRISK EAST FLOW.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 329 AM EDT TUE APR 7 2015
OUR MAIN CHALLENGES IN THE SHORT TERM WILL BE DETERMINING SEVERE
WEATHER CHANCES FOR THU...AND TIMING ROUNDS OF RAIN THROUGH THE AREA
THROUGH THU.
WE ARE SEEING A COUPLE OF AREAS OF RAIN SHOWERS MOVING THROUGH THE
AREA EARLY THIS MORNING. THESE RAIN SHOWERS ARE INSIGNIFICANT AS THE
MUCH BETTER MOISTURE REMAINS WELL SOUTH OF THE AREA SOUTH OF THE
COLD FRONT THAT DROPPED THROUGH THE AREA LAST EVENING. THE RAIN
SHOWERS REMAIN ASSOCIATED WITH A RRQ OF A 130 KNOT UPPER JET STREAK
THAT IS LEADING TO SOME MID LEVEL FGEN PROCESSES OVER THE AREA. WE
EXPECT MOST OF THIS TO BE GONE BY 12Z THIS MORNING.
AFTER A BREAK FOR MOST OF THE DAY TODAY...WE WILL SEE PCPN MOVE BACK
IN/DEVELOP OVER THE AREA BEGINNING TOWARD MIDNIGHT TONIGHT. THIS
PCPN WHICH SHOULD BE ALMOST ALL RAIN PER FCST SOUNDINGS WILL BE A
BIT MORE ROBUST. WE WILL SEE AN UPPER WAVE MOVE INTO THE AREA ON THE
SW FLOW ALOFT. THIS WAVE WILL HAVE BETTER SUPPORT AS THE LLJ WILL BE
AIMED CLOSER TO THE AREA BRINGING BETTER MOISTURE TO THE AREA. LATER
ON TONIGHT...THUNDER WILL BECOME POSSIBLE AS SUFFICIENT ELEVATED
INSTABILITY MOVES UP TO JUST SOUTH OF I-96. THE ELEVATED NATURE OF
THE STORMS WILL KEEP THE SEVERE THREAT FAIRLY LOW.
WE WILL HAVE A SIMILAR SET UP FOR THE WED/WED NIGHT TIME FRAME. WE
SHOULD SEE A BREAK FOR MOST OF THE AREA ON WED AS THE LLJ/MOISTURE
TRANSPORT CORE SHIFTS EAST. YET ANOTHER UPPER WAVE AND ASSOCIATED
LLJ/MOISTURE TRANSPORT AREA WILL MOVE IN ACROSS THE AREA FOR WED
NIGHT. THERE WILL BE A BETTER THREAT FOR STORMS ACROSS THE ENTIRE
CWFA AS A PLUME OF BETTER ELEVATED INSTABILITY MOVES IN. SEVERE WX
THREAT IS STILL LOW THROUGH WED NIGHT WITH THE INSTABILITY BEING
ELEVATED AND FCST SOUNDINGS INDICATING A LOWER THREAT FOR ALL OF THE
THREATS.
THU WILL BE THE DAY THAT PORTIONS OF THE AREA WILL SEE THE BEST CHC
FOR SOME SEVERE WX. WE WILL SEE THE MAIN LONG WAVE TROUGH ACROSS THE
WRN STATES LIFT NE TOWARD THE UPPER MIDWEST. THIS WILL LIFT THE
FRONT BACK NORTH ACROSS AT LEAST A PORTION OF THE AREA. HOW FAR
NORTH THE FRONT GOES WILL MAKE A BIG DIFFERENCE IN TEMPS AND SEVERE
WX THREAT WITH QUITE A TEMP GRADIENT ACROSS THE FRONT.
WE ARE TENDING TO THINK THE FRONT WILL LIFT TO ABOUT I-96 OR JUST
NORTH AS SOME OF THE MODELS SEEM TO BE OVERDEVELOPING THE SFC LOW
WITH THIS SYSTEM DUE TO EARLIER CONVECTION. THE WARM SECTOR COULD
SEE TEMPS GET INTO THE 70S WITH DEW POINTS POSSIBLY GETTING WELL
INTO THE 50S. THIS WOULD GENERATE SOME VALUES OF CAPE OVER 1000
J/KG. THE WARM FRONT WOULD BE A CONCERN WITH SOME DECENT DIRECTIONAL
SHEAR AS ONE WOULD EXPECT. SOME LARGE HAIL AND DAMAGING WINDS WOULD
BE POSSIBLE IN THE WARM SECTOR WITH FAIRLY HEALTHY CAPE IN THE -10
TO -30C LAYER AND UNIDIRECTIONAL WINDS. RAIN EARLIER ON MAY LIMIT
INSTABILITY SOME.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 329 AM EDT TUE APR 7 2015
THE LONG TERM LOOKS WET AT THE BEGINNING AND END BUT DRY OVER MUCH
OF THE WEEKEND.
WE/RE GOING TO HANG ONTO THE POSSIBILITY OF THUNDERSTORMS THURSDAY
NIGHT. THE GFS REMAINS SLOWER THAN THE ECMWF WHICH ALREADY MOVES LOW
PRESSURE OVER THE CENTRAL CWA BY 00Z FRIDAY. MEANWHILE THE GFS STILL
HAS THE LOW OVER EASTERN IOWA AND THE CWA IN THE WARM SECTOR. IF THE
ECMWF IS CORRECT...TSRA CHANCES WOULD BE LOWER THAN IF THE SLOWER
GFS VERIFIES. BOTH MODELS CLEAR THE TRAILING COLD FRONT BY FRIDAY
MORNING WHICH MEANS WE/LL DRY OUT FRIDAY LEADING TO SUNNY WEATHER
SATURDAY AND SUNDAY.
THE NEXT SIGNIFICANT WEATHER WILL BE A SOUTHERN STREAM LOW THAT
MOVES NORTHEAST FROM TEXAS LATE SUNDAY NIGHT AND MONDAY. THE GULF
LOOKS TO BE WIDE OPEN SO MOISTURE AVAILABILITY SHOULDN/T BE A
PROBLEM ESPECIALLY GIVEN THE 60+ KT LLJ. THIS LOOKS MOSTLY LIKE A
RAIN EVENT AS INSTABILITY APPEARS LIMITED.
TEMPS IN THE MID 50S FRIDAY WILL WARM TO THE MID 60S BY SUNDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 745 AM EDT TUE APR 7 2015
RADAR SHOWS LIGHT SHOWERS INCREASING OVER SOUTHWEST LOWER
MICHGIAN. SHOWERS WILL REMAIN IN THE VICINITY OF THE TAF SITES
THIS MORNING BUT LIKELY WON/T RESTRICT VISIBILITIES.
NORTHEAST WINDS HAVE ADVECTED IFR/MVFR CIGS FROM SAGINAW BAY INTO
LANSING AND JACKSON. IT/S POSSIBLE THAT WE/LL SEE THESE CIGS
BOUNCE AROUND A BIT...AS LANSING HAS JUST SCATTERED OUT. IFR CIGS
SHOULD BE A THREAT UNTIL WINDS VEER MORE TO THE EAST RATHER THAN
NORTHEAST AND TAKE THE LAKE OUT OF PLAY.
&&
.MARINE...
ISSUED AT 329 AM EDT TUE APR 7 2015
WE WILL BE LEAVING THE SMALL CRAFT ADVISORY AS IS WITH THIS FCST
PACKAGE. A FAIRLY STIFF E/NE GRADIENT WILL REMAIN IN PLACE THROUGH
TODAY AND INTO WED MORNING. WAVES WILL NOT BE TOO SIGNIFICANT ON
THIS SIDE OF THE LAKE WITH THE OFFSHORE COMPONENT.
&&
.HYDROLOGY...
ISSUED AT 221 PM EDT MON APR 6 2015
RIVERS AND STREAMS ACROSS SOUTHWEST LOWER MICHIGAN ARE RUNNING A
LITTLE BELOW NORMAL. RIVER LEVELS ARE CURRENTLY SLOWLY
FALLING...BUT RISES IN RIVER LEVELS DUE TO RAINFALL ARE EXPECTED
LATER THIS WEEK. 1 TO 2 INCHES OF WIDESPREAD RAINFALL IS POSSIBLE
OVER THE NEXT 7 DAYS...WITH THE POTENTIAL FOR SEVERAL INCHES IF
THUNDERSTORMS MOVE OVER THE SAME AREAS. IN GENERAL...SEVERAL
ROUNDS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED WEDNESDAY NIGHT
INTO FRIDAY. STRONGER STORMS ARE CERTAINLY POSSIBLE DURING THIS
TIMEFRAME...SO THERE IS A RISK FOR LOCALLY HEAVY RAINFALL.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT WEDNESDAY FOR LMZ844>849.
&&
$$
UPDATE...MEADE
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...99
AVIATION...04
HYDROLOGY...EBW
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
737 AM EDT TUE APR 7 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 421 AM EDT TUE APR 7 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR MI UNDER A
CONFLUENT WNW FLOW ALOFT BTWN ARCTIC BRANCH CLOSED LO OVER NRN
QUEBEC AND SRN BRANCH RDG IN THE PLAINS DOWNSTREAM OF TROF ALONG THE
W COAST. UPR MI REMAINS IN THE RRQ OF 130KT H3 JET MAX WITHIN THE
CONFLUENCE ZN OF THESE TWO BRANCHES. WV IMAGERY AND RUC ANALYSIS
ALSO INDICATE A SHRTWV OVER NDAKOTA THAT IS SLIDING TO THE E. THE
DPVA/MID LVL QVECTOR CNVGC AHEAD OF THIS SHRTWV AND SOME UPR
DVGC/MID LVL FGEN IN THE RRQ OF THE UPR JET ARE AIDING A LINE OF
LIGHT SN/MIXED PCPN ACRS NCENTRAL WI INTO FAR SRN MNM COUNTY WELL TO
THE N OF FAIRLY SHARP H85 WARM FNT ORIENTED W-E ACRS THE LOWER LKS.
HOWEVER...THE NNE LLVL FLOW OF VERY DRY AIR SHOWN ON THE 00Z INL
RAOB TO THE S OF HI PRES STRETCHING FM NEAR LK WINNIPEG ACROSS NW
ONTARIO AND INTO QUEBEC IS PREVENTING THIS PCPN FM MOVING FARTHER TO
THE N. BUT THERE ARE PLENTY OF MID/HI CLDS OVER THE CWA...THICKEST
OVER THE SRN TIER. LOOKING FARTHER UPSTREAM...ANOTHER SHRTWV IS
LIFTING TOWARD THE NRN PLAINS IN THE SW FLOW ALOFT BTWN THE PLAINS
RDG AND THE TROF ALONG THE W COAST.
MAIN FCST CONCERNS THRU TNGT WL BE POPS ALONG THE WI BORDER EARLY
THIS FCST PERIOD IN ASSOCIATION WITH THE SHRTWV NOW APRCH MN. FOCUS
FOR TNGT WL BE ON IMPACT OF SECOND DISTURBANCE APRCHG THE NRN PLAINS
AND ANOTHER DISTURBANCE THE MODELS SHOW WL MOVE THRU WI.
TDAY...FIRST SHRTWV OVER NW MN IS FCT TO DRIFT TO THE E AND INTO RRQ
OF UPR STREAK TO THE E...ACCOMPANIED BY AN AREA OF DEEP LYR QVECTOR
CNVGC. ALTHOUGH THIS SETUP WOULD NORMALLY SUPPORT WDSPRD PCPN...ALL
THE MODELS SHOW A STEADY FEED OF SFC-H85 DRY AIR FM THE NE THRU THE
DAY. IN FACT...AFTER LINGERING PCPN ENDS EARLY THIS MRNG OVER FAR
SRN MENOMINEE COUNTY...ALL OF THE MODELS SHOW NO PCPN OVER UPR MI
THRU 00Z THIS EVNG. BUT WITH CONSIDERABLE MID/HI CLD ABOVE THE LLVL
DRY AIR AND AN ENE WIND OFF THE CHILLY LK WATERS...MAX TEMPS THIS
AFTN SHOULD RUN BLO NORMAL. EXPECT READINGS TO REACH THE LO 40S AWAY
FM THE LKS...WHERE TEMPS WL HOLD IN THE 30S.
TNGT...AS THE CONFLUENCE ZN SHIFTS SLOWLY TO THE NE TDAY...SHRTWV
NOW TRACKING INTO THE NRN PLAINS IS FCST TO LIFT NE INTO SCENTRAL
CANADA...WITH BULK OF DEEP LYR QVECTOR CNVGC PASSING TO THE NW. BUT
GENERAL MODEL CONSENSUS ALSO HINTS ANOTHER SHRTWV EMERGING FM THE
WRN TROF AND THRU THE PLAINS TDAY WL DRIFT INTO WI LATE TNGT...
ACCOMPANIED BY AREA OF FAIRLY SHARP UPR DVGC EVEN AS THE MAIN UPR
JET CORE TO THE E SLIPS FARTHER AWAY ALONG WITH THE UPR CONFLUENCE
ZN. MOST OF THE MODELS FOCUS SOMEWHAT HIER QPF OVER THE SCNTRL
CWA...CLOSER TO WHERE THE CORE OF UPR DVGC/AXIS OF SHARPEST MID LVL
FGEN TO THE N OF H85 WARM FNT THAT IS FCST TO LIFT NWD WITH THE APRCH
OF THIS DISTURBANCE. DESPITE THE GENERAL AGREEMENT ON THESE
FEATURES...MODEL QPF AND FCST THERMAL FIELDS ARE QUITE VARIABLE. THE
GFS IS WETTEST OVERALL...SHOWING AS MUCH AS 0.25-0.35 INCH OVER THE
SCNTRL CLOSER TO THE SHARPER FORCING/FGEN AND WHERE THIS MODEL SHOWS
H7 SPECIFIC HUMIDITY IN THE 3-4 G/KG RANGE. BUT MANY OF THE HIER RES
MODELS...LIKE THE 00Z NAM AND REGIONAL CNDN...SHOW LTL IF ANY PCPN
EVEN THERE. GIVEN PERSISTENCE OF LLVL DRY AIR OVER THE NE CWA AND THE
WEAKENING OF THE FORCING WITH TIME AS THE DISTURBANCE LIFTS TO THE
NE...WL TEND TO KEEP THE NE CWA DRIER LONGER. PTYPE WL BE A
CONCERN...AND MODEL DIFFERENCES COMPOUND THE UNCERTAINTY. SINCE THE
GFS SHOWS MORE VERTICAL MOTION/QPF AND THUS MORE DYNAMIC/EVAPORATIVE
COOLING...THAT MODEL FCST SDNGS INDICATE A MAINLY SN EVENT...WITH SN
AMOUNTS OVER THE SCENTRAL AT LEAST APRCHG ADVY CRITERIA. CONSIDERING
THE WIDE DIFFERENCES IN QPF/IMPACT OF LINGERING DRY AIR...DID NOT
CONSIDER AN ADVY ATTM EVEN THOUGH TRACK OF DISTURBANCE TO THE S AND
VERY DRY NATURE OF THE ANTECEDENT AIRMASS WOULD FAVOR MAINLY SN. MANY
OF THE OTHER MODELS SHOW AN ELEVATED WARM LYR WITH MAX TEMPS ALOFT
OVER 0C. WITH LLVL DRY AIR THAT WL ALLOW FOR MORE NEAR SFC
COOLING...FREEZING RA AND PERHAPS SLEET...ESPECIALLY NEAR THE ONSET
OF THE PCPN WHEN THE LLVLS ARE DRIER AND WBLB TEMPS LO ENUF TO ALLOW
FOR A BETTER CHC FOR THE DROPS TO FREEZE INTO ICE PELLETS...ARE
POSSIBLE. SO RETAINED A MENTION OF THESE PTYPES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 359 AM EDT TUE APR 7 2015
THE SECOND HALF OF THE WORK WEEK CONTINUES TO LOOK ACTIVE WITH
PERIODS OF MIXED PRECIPITATION...BEFORE TRENDING DRIER WITH NORMAL
TO ABOVE NORMAL TEMPERATURES THIS WEEKEND. ANOTHER UPPER TROUGH
WILL AFFECT THE REGION FOR THE START OF NEXT WEEK...BUT AT THIS
POINT...THERMAL PROFILES SUPPORT RAIN FOR THE PRECIP TYPE.
TO START THE LONG TERM PERIOD...THE SHORTWAVE THAT WILL BE
PRODUCING PRECIPITATION OVER PARTS OF THE UPPER GREAT LAKES REGION
WILL BE QUICKLY SHIFTING EAST OUT OF THE THE AREA WEDNESDAY MORNING.
THIS MAY LEAD TO SOME LINGERING SHOWERS TO DURING THE MORNING AND
WITH THE DEEP MOISTURE DEPARTING IT WILL LEAD TO A WINTRY MIX IF
PRECIPITATION OCCURS. WHILE THE LARGE SCALE SUPPORT DEPARTS AT THE
START OF THE PERIOD...THE HIGH PRESSURE RIDGE WILL ALSO QUICKLY
LEAVE THE REGION AND ALLOW FOR PLENTY OF CLOUDS TO REMAIN OVER THE
U.P. FOR WEDNESDAY. THE LATEST TRENDS IN THE MODELS IS FOR LOW LEVEL
MOISTURE TO REMAIN OVER THE AREA...AND WITH SOUTHEASTERLY 950-925MB
FLOW DEVELOPING THROUGH THE DAY...EXPECT THERE TO BE SOME UPSLOPE
DRIZZLE FOR THE HIGHER TERRAIN OF CENTRAL UPPER MICHIGAN. THE
GFS CONTINUES TO HIGHLIGHT EVEN MEASURABLE DRIZZLE BUT WITH MUCH OF
THE OTHER MODELS SHOWING DRY NEAR SURFACE AIR...WILL ONLY SHOW
SLIGHT CHANCE POPS FOR THE DRIZZLE.
ATTENTION THEN TURNS TO THE UPPER TROUGH LIFTING NORTHEAST OUT OF
THE CENTRAL PLAINS WEDNESDAY NIGHT AND PHASING WITH A WAVE MOVING
THROUGH CANADA THURSDAY AFTERNOON INTO THURSDAY NIGHT AS IT MOVES
THROUGH THE UPPER GREAT LAKES REGION. THERE CONTINUES TO BE TWO
WAVES OF PRECIPITATION EXPECTED WITH THIS SYSTEM. THE FIRST WILL BE
TIED TO THE STRONG WARM AIR ADVECTION AND LEADING SHORTWAVE LIFTING
NORTHEAST THROUGH THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY
MORNING. MODEL CONSENSUS HAS THE BEST SHORTWAVE ENERGY MISSING THE
U.P. TO THE SOUTHEAST BUT THEY DIFFER ON WHERE THE FOCUS OF THE BEST
WARM AIR ADVECTION WILL BE OVER THE U.P. THUS...CONFIDENCE REMAINS
LOW ON THE TRACK OF THE HEAVIEST PRECIPITATION (0.15-0.3IN OF
LIQUID...HIGHEST OVER THE SOUTH CENTRAL). AS FOR PRECIP TYPE...WITH
900-800MB TEMPERATURES WELL ABOVE FREEZING WITHIN THAT BEST
FORCING...WOULD EXPECT THE PRECIPITATION TO FALL AS RAIN. WHICH
LEAVES THE SURFACE TEMPERATURES TO DETERMINE WHETHER IT IS FREEZING
RAIN OR NOT. ONE POSITIVE WITH THE WARMER WEATHER OVER THE LAST
COUPLE OF WEEKS IS THAT IT HAS HELPED WARM THE SURFACE TEMPERATURES
ACROSS THE AREA. TODAY...EVEN WITH THE COOLER TEMPERATURES...ROAD
SURFACE TEMPERATURES WERE IN THE MID-UPPER 30S. THUS...WITH THE
CLOUDS ON WEDNESDAY INTO WEDNESDAY NIGHT HELPING TO INSULATE AND
KEEP LOWS AROUND 30 DEGREES (TRENDED THEM UP A COUPLE DEGREES)...THE
IMPACT OF THE FREEZING RAIN MAY BE A LITTLE LESS (ESPECIALLY IF
ROADS ARE TREATED IN ADVANCE). WILL CONTINUE TO ADDRESS THIS
FREEZING RAIN THREAT IN THE HWO.
AFTER A BRIEF LULL IN THE STRONGER PRECIPITATION ON THURSDAY
AFTERNOON...THE UPPER TROUGH WILL LIFT NORTHEAST THROUGH THE UPPER
GREAT LAKES REGION THURSDAY NIGHT INTO FRIDAY MORNING WHILE THE
SURFACE LOW TRACKS FROM CENTRAL IOWA AT 18Z THURSDAY TO NORTHERN
LAKE HURON AT 18Z ON FRIDAY. VERY CONFIDENT ON PRECIPITATION
OCCURRING DURING THAT PERIOD...BUT CONFIDENCE IS LACKING ON THE
AMOUNTS/LOCATION DUE TO DIFFERENCES WITH THE TRACK/INTENSITY OF THE
LOW AND THE MID LEVEL FGEN BAND. THIS IS ALL TIED TO THE PHASING OF
THE TWO WAVES...WHICH IS NOTORIOUSLY DIFFICULT FOR MODELS TO PIN
DOWN AT THIS STAGE. THUS...WILL FOLLOW A GENERAL CONSENSUS OF THE
MODELS (LEANING TOWARDS GFS/ECMWF) BOTH FOR QPF AND THERMAL FIELDS
AS THAT SEEMS TO REPRESENT THE POSSIBILITIES THE BEST AT THIS TIME.
AT THIS POINT...THINK THE GEM/NAM SEEM LIKE THE OUTLIERS WITH THE
FARTHER NORTHWEST TRACK (ALONG LAKE MICHIGAN AND THE U.P. SHORELINE)
WITH THE 12Z ECMWF AND 00Z GFS ENSEMBLE MEMBERS SUPPORTING A TRACK
MORE THROUGH NORTHERN LOWER MICHIGAN. THE LATE ARRIVING 00Z ECMWF
REMAINS MUCH WEAKER THAN THE OTHER SOLUTIONS...AS IT HAS
TRENDED TOWARDS LESS PHASING AND MORE OF A GLANCING BLOW BY THE
NORTHERN STREAM WAVE. IF THAT VERIFIES...IT WOULD LEAD TO MUCH LESS
PRECIPITATION FOR THE AREA FOR THE THURSDAY NIGHT PERIOD AND DRY BY
FRIDAY AFTERNOON. EXPECT THE PRECIP TO START AS RAIN INITIALLY AND
THEN GRADUALLY TRANSITION TO OR MIX WITH SNOW FROM WEST TO EAST.
WITH ALL OF THE UNCERTAINTY...DON/T WANT TO GET TOO HUNG UP IN
SNOWFALL AMOUNTS...BUT THERE COULD BE SLUSHY ACCUMULATIONS WEST OF
A LINE FROM MARQUETTE TO CRYSTAL FALLS. THIS SECOND WAVE OF PRECIP
IS STILL AN EVOLVING SITUATION THAT WILL NEED TO BE FINE TUNED OVER
THE NEXT SEVERAL SHIFTS.
THE UPPER TROUGH AND SURFACE LOW WILL QUICKLY DEPART FRIDAY NIGHT
AND BRING A QUICK DRYING TREND TO THE AREA AS A SURFACE RIDGE MOVES
EAST OVER THE AREA BY SATURDAY MORNING. WITH LIMITED COLD AIR
BEHIND THIS SYSTEM AND AN UPPER RIDGE MOVING INTO THE UPPER GREAT
LAKES REGION...SHOULD SEE NEAR NORMAL TEMPERATURES ON SATURDAY WITH
MOSTLY SUNNY SKIES. THAT UPPER/SURFACE RIDGE WILL SHIFT EAST ON
SATURDAY NIGHT...LEADING TO SOUTHWESTERLY WINDS BRINGING WARMER AIR
TO THE AREA FOR SUNDAY AND HAVE HIGHS RISING INTO THE UPPER 50S
OVER THE WEST AND AROUND 50 OVER THE EAST. THAT SOUTHWESTERLY FLOW
WILL BE OUT AHEAD OF THE NEXT UPPER TROUGH THAT WILL BE MOVING
ACROSS THE CANADIAN ROCKIES THIS WEEKEND AND IMPACTING THE AREA
SUNDAY NIGHT INTO THE FIRST PART OF NEXT WEEK. AT THIS POINT...THE
THERMAL PROFILES WOULD SUPPORT RAIN FOR MONDAY AND WILL SHOW
INCREASING POPS SUNDAY NIGHT AND CONTINUE CHANCE POPS INTO MONDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 736 AM EDT TUE APR 7 2015
STEADY ENE WIND ON THE SRN FLANK OF HI PRES RIDGE EXTENDING ACROSS
NW ONTARIO WILL ADVECT LLVL DRY AIR INTO UPR MI THRU THIS EVNG...
RESULTING IN VFR CONDITIONS DESPITE CONSIDERABLE MID/HI CLDS. AS A
DISTURBANCE MOVES INTO THE GREAT LKS TNGT...SOME LIGHT PCPN MAY
IMPACT IWD AND SAW OVERNGT. IF THE LLVL DRY AIR CAN BE OVERCOME...
MVFR CONDITIONS MAY IMPACT SAW AND ESPECIALLY IWD...WHICH WL BE
FARTHER FM THE CORE OF THE DRY AIR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 421 AM EDT TUE APR 7 2015
WITH LAKE SUPERIOR SITUATED BETWEEN HI PRES THAT WILL MOVE ACROSS NW
ONTARIO INTO QUEBEC THRU WED AND A WARM FRONT THAT WILL REMAIN TO
THE S AND SW ACROSS THE PLAINS TO OHIO VALLEY...E TO NE WINDS WILL
PERSIST. TYPICAL FOR E TO NE WINDS...WINDS WILL BE STRONGEST OVER
WRN LAKE SUPERIOR...IN PARTICULAR BTWN THE APOSTLE ISLANDS AND MN
NSHORE WHERE FUNNELING/COASTAL CONVERGENCE ENHANCE THE WINDS. IN
THAT AREA...15-25KT WINDS WILL INCREASE TO 20-30KT THIS MORNING INTO
THIS EVENING. E TO NE WINDS...MOSTLY 10-20KT...WILL THEN CONTINUE ON
WED AND ON INTO THU AS LO PRES LIFTS NE FROM THE CENTRAL PLAINS
TOWARD THE GREAT LAKES REGION. AT THIS TIME...NO GALES APPEAR
LIKELY. BUT WINDS WILL BACK TO THE N AND THEN NW UP TO 25 KTS THU
NIGHT INTO FRI ONCE THE LO SHIFTS TO THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
634 AM CDT TUE APR 7 2015
.SYNOPSIS...
ISSUED AT 400 AM CDT TUE APR 7 2015
H5 ANALYSIS FROM TONIGHT HAS A CLOSED LOW OVER NRN QUEBEC...WITH
A BROAD TROUGH EXTENDING SWD INTO NEW ENGLAND. FURTHER WEST...A
SECOND LOW WAS PRESENT OFF THE COAST OF SWRN OREGON WITH A TROUGH
EXTENDING SWD TO OFF THE COAST OF CENTRAL CALIFORNIA. AT THE
SURFACE...LOW PRESSURE WAS PRESENT OVER NORTHERN COLORADO...WITH A
STATIONARY FRONT EXTENDING ESE INTO WESTERN KS...THEN EAST
NORTHEAST INTO EAST CENTRAL KS. NORTH OF THIS FEATURE
TONIGHT...EASTERLY WINDS AND PLENTY OF LOW LEVEL MOISTURE HAVE
PUSHED INTO WESTERN AND NORTH CENTRAL NEBRASKA. IN ADDITION TO
AREAS OF FOG...OCCASIONAL DRIZZLE WAS REPORTED AT MOST OBSERVATION
STATIONS ACROSS THE FORECAST AREA OVERNIGHT TONIGHT. WITH CLOUDY
SKIES PRESENT ACROSS ALL OF WESTERN AND NORTH CENTRAL
NEBRASKA...TEMPERATURES RANGED FROM 36 AT VALENTINE TO 50 AT
BROKEN BOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT TUE APR 7 2015
OVER THE NEXT 24 HOURS...THE MAIN FORECAST CHALLENGE IS
PRECIPITATION CHANCES...ALONG WITH THE THREAT OF FOG AND DRIZZLE.
FOR THIS MORNING...LOW POPS WILL CONTINUE DUE TO A COMBINATION OF
OCCASIONAL DRIZZLE WHICH WILL BE HEAVY ENOUGH TO MEASURE...AND THE
THREAT FOR SHOWERS IN ASSOCIATION WITH A WEAK DISTURBANCE AND MID
LEVEL MOISTURE WHICH WILL CROSS THE SANDHILLS AND NORTHERN
NEBRASKA THIS MORNING. PRECIPITATION CHANCES WILL COME TO AN END
TEMPORARILY THIS AFTERNOON...AS THE BOUNDARY LAYER WARMS AND CIGS
LIFT...ALONG WITH MID LEVEL MOISTURE EXITING THE FORECAST AREA TO
THE EAST. FOR THE MOST PART...SKIES WILL REMAIN CLOUDY TODAY
ACROSS THE FORECAST AREA...AS WE REMAIN UNDER A THICK VEIL OF
STRATUS. THE EXCEPTION MAY BE ACROSS THE PANHANDLE COUNTIES...AS
THE LATEST HRRR AND NAM DO INDICATE SOME SCATTERING OUT OF CLOUDS
DURING PEAK HEATING THIS AFTERNOON. HOWEVER...THE MODELS INDICATED
A DECENT AMOUNT OF CLEARING FOR YESTERDAY WITH HEATING...WHICH FOR
THE MOST PART...DIDN/T MATERIALIZE. WITH THIS IN MIND...WENT
COOLER ON HIGHS TODAY THAN GUIDANCE...HEDGING ON CLOUDS REMAINING
ENTRENCHED ACROSS THE FORECAST AREA TODAY. CIGS WILL LOWER THIS
EVENING...WITH ANOTHER ROUND OF DRIZZLE AND FOG ACROSS THE
FORECAST AREA. FCST SOUNDINGS AND CROSS SECTIONS INDICATE A NEAR
SATURATED LAYER FROM THE SFC TO H85 TONIGHT...COLLOCATED WITH WEAK
OMEGA IN THIS LAYER AND VERY DRY CONDS ALOFT. DID GO AHEAD AND
INCREASE POPS OVERNIGHT AS SOME MID LEVEL MOISTURE LIFTS INTO THE
FORECAST AREA FROM THE SOUTHWEST...WHICH MAY LEAD TO LIGHT
PRECIPITATION IN ADDITION TO ANY DRIZZLE WHICH IS EXPECTED AS
WELL. LOWS TONIGHT WILL BE MILD GIVEN THE CLOUD COVER AND MOIST
BOUNDARY LAYER CONDS...WITH READINGS RANGING FROM THE UPPER 30S IN
THE FAR NORTH...TO LOWER TO MID 40S IN THE CENTRAL AND SOUTH.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 400 AM CDT TUE APR 7 2015
FORECAST CONCERNS CONTINUE TO DEAL WITH DRIZZLE/FOG/RAIN CHANCES
THROUGH WEDNESDAY WHICH BRING UP THE CONCERN OF TEMPERATURES. THEN
FOCUS TURNS TO MAIN UPPER LEVEL SYSTEM MOVING ACROSS THE CENTRAL
PLAINS THURSDAY WHICH BRINGS CHANCES FOR RAIN/SNOW AND STRONG WINDS
TO THE FORECAST AREA. THE PATTERN THEN REMAINS ACTIVE AS THE LOCAL
AREA GETS IMPACTED BY SYSTEMS MOVING THROUGH BOTH THE NORTHERN AND
SOUTHERN STREAMS INTO THE FIRST PART OF NEXT WEEK.
FORECAST MODELS ARE IN FAIRLY GOOD AGREEMENT THROUGH THE
PERIOD...HOWEVER THERE HAVE BEEN SOME RUN TO RUN INCONSISTENCIES
WHICH HAS KEPT CONFIDENCE LOWER THAN WOULD BE DESIRED.
BEGINNING ON WEDNESDAY...THE PRIMARY UPPER LEVEL LOW WILL MOVE INTO
THE CENTRAL ROCKIES WITH A WEAK SHORTWAVE TROUGH EJECTING OUT AHEAD
OF THE MAIN SYSTEM DURING THE DAY WEDNESDAY. MODELS CONTINUE TO
DEVELOP QPF OVER MUCH OF NEBRASKA ON WEDNESDAY...HOWEVER LOOKING AT
MOISTURE PROFILES IN CROSS SECTIONS ACROSS THE AREA AND FORECAST
SOUNDINGS...THE MOISTURE REMAINS QUITE SHALLOW...BELOW 750MB. THE
LIFT ASSOCIATED WITH THE SHORTWAVE TROUGH DOES HELP PROVIDE LIFT
THROUGH THE COLUMN BUT WITH THE AIR ABOVE 750MB BEING SO EXTREMELY
DRY...THIS LIFT WILL NOT HAVE ANYTHING TO WORK WITH AND SO WILL HAVE
NO IMPACT ON THE FORECAST. IF THERE WOULD BE MOISTURE...COULD ARGUE
FOR NEEDING MENTION OF THUNDERSTORMS AS THE LAPSE RATES ARE QUITE
STEEP LEADING TO AT LEAST SOME INSTABILITY...BUT AGAIN NO MOISTURE
WILL PROHIBIT THE NEED FOR THUNDER MENTION. BACK TO THE LOW
LEVELS...THERE IS DECENT LIFT WITHIN THE SATURATED LAYER AND WITH
LIGHT EASTERLY WINDS CONTINUING THROUGH WEDNESDAY NIGHT...THE SLIGHT
UPSLOPE FLOW WILL HELP KEEP STRATUS/FOG/DRIZZLE POTENTIAL THROUGH
THE DAY. WITH THIS EXPECTATION...DON/T THINK TEMPERATURES WILL RISE
MUCH THROUGH THE DAY WEDNESDAY AND HAVE LOWERED HIGHS SUBSTANTIALLY.
THE FRONT WILL BE JUST SOUTH OF THE FORECAST AREA SO THERE MAY BE A
TIGHT GRADIENT WHERE CLOUDS/COLDER TEMPERATURES EXIST TO WHERE THERE
IS PLENTIFUL SUNSHINE AND HIGHS UP INTO THE 70S. BELIEVE THAT THIS
WILL BE SOUTH OF THE FORECAST AREA THROUGH.
THE WHOLE UPPER LEVEL SYSTEM CONTINUES TO MOVE EAST THROUGH THE DAY
THURSDAY...AND WHILE THEY ARE IN AGREEMENT WITH THE UPPER LOW
PASSING OVER THE REGION AND DUMPING SOME DECENT MOISTURE ACROSS THE
FORECAST AREA...THESE SOLUTIONS ARE DIFFERENT FROM PRIOR RUNS AS ALL
ARE NOW MOVING THE SYSTEM ACROSS THE AREA AS AN OPEN WAVE AND IN
TURNS MOVES IT ACROSS THE AREA FASTER...WITH PRECIPITATION ENDED BY
MID-DAY THURSDAY. THEY STILL PRODUCE QUITE A BIT OF QPF ON THE
NORTHWEST SIDE OF THE FORECAST AREA DESPITE MOVING ACROSS THE AREA
FASTER THAN WAS EARLIER THOUGHT. DID REMOVE MENTION OF
THUNDERSTORMS FOR WEDNESDAY NIGHT AND THURSDAY. THE FRONT WILL
REMAIN WELL SOUTH AND EAST OF THE LOCAL AREA AS THE SURFACE LOW
STAYS ACROSS KANSAS AS IT MOVES EASTWARD. THIS WILL KEEP THE
WARMER AIR...PLUS ANY MOISTURE ADVECTION/LIFT ALONG THE FRONT AWAY
FROM THE LOCAL AREA. AND...THE LOW LEVEL JET WILL BE WELL TO THE
EAST SO REALLY NOT CONCERNED ABOUT THUNDERSTORMS. THEN ON THURSDAY
AS THE SURFACE LOW ACROSS KANSAS TRANSITIONS INTO THE MISSISSIPPI
RIVER VALLEY THE PRESSURE GRADIENT WILL TIGHTEN...BRINGING STRONG
NORTHERLY WINDS TO THE FORECAST AREA. THIS WILL LEAD TO CONDITIONS
FEELING QUITE RAW AS APPARENT TEMPERATURES ARE LOOKING TO BE IN
THE 20S AND 30S. WITH THE COOLER AIR MOVING IN FROM THE NORTH...IT
IS LIKELY THAT THE PRECIPITATION WILL CHANGE OVER TO A RAIN/SNOW
MIX AND THEN OVER TO SNOW COMPLETELY OVER PARTS OF THE PANHANDLE.
DON/T THINK AMOUNTS WILL BE MUCH...BUT COULD SEE THE GROUND BECOME
WHITE FOR A SHORT PERIOD IN PLACES.
AGAIN AS THIS IS NOT MOVING THROUGH AS AN OPEN WAVE...IT WILL MOVE
THROUGH THE LOCAL AREA QUICKLY AND HAVE ENDED PRECIPITATION
CHANCES ABOUT 6 HOURS EARLIER THAN IN THE PRIOR FORECAST.
SHORTWAVE RIDGING BUILDS INTO THE CENTRAL PLAINS BRIEFLY FRIDAY
NIGHT...WHILE AN UPPER LOW IN THE SOUTHERN STREAM MOVES ACROSS THE
SOUTHERN CONUS AND NORTHERN MEXICO. MEANWHILE ANOTHER POTENT
SYSTEM MOVES INTO THE PACIFIC NORTHWEST. THESE SYSTEMS WILL BOTH
PROGRESS EASTWARD AND THERE IS SOME INDICATION THAT THEY MAY
ATTEMPT TO INTERACT EARLY NEXT WEEK WHICH COULD BRING ANOTHER WET
PERIOD TO THE FORECAST AREA FOR MONDAY AND TUESDAY. CONFIDENCE IS
NOT HIGH IN THIS OCCURRING RIGHT NOW SO WILL MAINTAIN LOW END
PRECIPITATION CHANCES FOR NOW.
ULTIMATELY WITH THE MORE ACTIVE PATTERN...WILL SEE MORE CHANCES
FOR PRECIPITATION...AND TEMPERATURES CLOSER TO NORMAL...ALTHOUGH
THERE WILL BE DAYS WITH HIGHER TEMPERATURES. HOWEVER THERE ARE NO
CURRENT INDICATIONS OF ANOTHER PERIOD OF WELL ABOVE NORMAL
TEMPERATURES FOR THE FORECAST AREA AT THIS TIME.
AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1142 PM CDT MON APR 6 2015
LIFR CEILINGS CURRENTLY AT THE KLBF AND KVTN TERMINALS IS FORECAST
TO PERSIST UNTIL 15Z. VSBY WILL LIKELY RANGE NEAR 1SM -DZ BR AT
KVTN WHILE LOWERING TO 3SM -DZ BR AT KLBF. AFTER 15Z...CEILINGS
AND VSBYS WILL IMPROVE TO IFR...AND TO MVFR AFTER 18Z.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 635 AM CDT TUE APR 7 2015
OVERCAST SKIES ARE EXPECTED OVER THE NEXT 24 HOURS AT BOTH THE
KLBF AND KVTN TERMINALS WITH MVFR AND IFR CIGS TODAY...AND THE
THREAT FOR LIFR CIGS TONIGHT. FOR THE KLBF TERMINAL...EXPECT MVFR
CIGS TODAY WITH CLOUD DECKS RANGING FROM 1600 TO 2200 FT AGL. SOME
CIGS MAY BE AROUND 700 FT AGL THIS MORNING. CIGS WILL FALL TO 600
TO 1200 FT AGL AFTER MID EVENING TONIGHT. FOR THIS
MORNING...PERIODS OF DRIZZLE ARE POSSIBLE WITH VISBYS AS LOW AS
3SM. DRIZZLE WILL BE POSSIBLE ONCE AGAIN OVERNIGHT TONIGHT WITH
VISBYS DOWN TO 4SM. FOR THE KVTN TERMINAL...EXPECT CIGS RANGING
FROM 300 TO 500 FT AGL THIS MORNING. CIGS WILL CLIMB TO AROUND
1300 FT AGL LATER TODAY...FALLING TO 400 TO 700 FT AGL THIS
EVENING. DRIZZLE WILL BE POSSIBLE THIS MORNING WITH VISBYS RANGING
FROM 1 TO 3SM. DRIZZLE WILL BE POSSIBLE ONCE AGAIN TONIGHT WITH
VISBYS AROUND 4SM .
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...BROOKS
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS RALEIGH NC
650 AM EDT TUE APR 7 2015
.SYNOPSIS...AN UPPER LEVEL DISTURBANCE WILL PASS OVER THE AREA THIS
MORNING. A WARM FRONT WILL LIFT NORTHWARD THROUGH THE REGION LATER
TODAY... KEEPING A WARM MOIST AIR MASS OVER NORTH CAROLINA THROUGH
WEDNESDAY. A BACKDOOR COLD FRONT TO OUR NORTH WILL DIP SOUTHWARD
INTO NORTHEAST NORTH CAROLINA LATE WEDNESDAY... THEN LIFT BACK NORTH
OF THE AREA ON THURSDAY.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 250 AM TUESDAY...
AN UNSETTLED PERIOD OF WEATHER BEGINS TODAY AND EXTENDS THROUGH LATE
IN THE WORK WEEK. A SHORTWAVE ALOFT (MOST EVIDENT AT 850-700 MB) AND
RESULTANT AREA OF SHOWERS NOW MOVING THROUGH THE CWA WILL BE MOVING
TO OUR EAST BY MID TO LATE MORNING... ALTHOUGH THE HIGH WATER
CONTENT (PW NEAR 200% OF NORMAL) AND POTENTIAL FOR WEAK INSTABILITY
NECESSITATES LEAVING IN A LOW CHANCE FOR A SHOWER OR TWO BEHIND THIS
CURRENT SHOWER AREA FROM LATE MORNING THROUGH EARLY AFTERNOON... IN
ACCORD WITH THE LATEST HRRR MODEL RUNS... DESPITE SOME POST-WAVE
SUBSIDENCE. WE SHOULD SEE AN UPTICK IN INSTABILITY THIS AFTERNOON...
ALTHOUGH THIS SHOULD REMAIN ON THE WEAK SIDE WITH NAM MUCAPE OF 500-
750 J/KG AT MOST... AND DEEP LAYER SHEAR WILL BE MARGINAL AT AROUND
25-30 KTS. LARGE SCALE MODELS SHOW A WEAK MID LEVEL PERTURBATION
MOVING IN FROM THE WEST LATE TODAY INTO EARLY THIS EVENING... AND
THIS SEEMS TO CORRELATE WITH A BROKEN BAND OF CONVECTION NOW
EXTENDING FROM LOWER MI TO A MORE ORGANIZED COMPLEX OVER SRN IL TO
AR/ERN TX. EXTRAPOLATION OF THIS CONVECTION AND ITS ACCOMPANYING
STRONG BUT WANING UPPER DIVERGENCE BRINGS IT INTO WRN NC EARLY THIS
EVENING... A TIMING SUPPORTED BY THE HRRR AND HI-RES ARW/NMM MODELS.
WILL REFLECT THE RELATIVE LULL IN PRECIP BEFORE RAMPING BACK UP TO
HIGH CHANCE/LIKELY POPS LATER THIS AFTERNOON INTO EARLY/MID
EVENING... LEAVING IT AS PRIMARILY SHOWERS (DUE TO UNIMPRESSIVE
FORECAST CAPE/SHEAR) AND ISOLATED STORMS. EXPECT PRECIP CHANCES TO
DROP BACK TO A 10-20% CHANCE AT MOST OVERNIGHT WITH LOSS OF HEATING
AND POST-WAVE SINKING AIR HELPING TO DRY OUT THE MID-UPPER LEVELS
SOMEWHAT. THE MILD START TO THE DAY AND ANTICIPATED BREAK IN THE
PRECIP ALONG WITH THICKNESSES NEARLY 20 M ABOVE NORMAL SHOULD ALLOW
TEMPS TO PEAK TODAY IN THE 73-79 RANGE DESPITE PLENTY OF CLOUDS.
WARM LOWS TONIGHT OF 59-65 WITH AREAS OF FOG. -GIH
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 325 AM TUESDAY...
WE`LL BE FIRMLY IN THE WARM SECTOR WED WITH PW VALUES HOLDING NEAR
200% OF NORMAL. WE SHOULD INITIALLY SEE WEAK SUBSIDENCE BEHIND THIS
EVENING`S WAVE AS IT SHIFTS OFF THE NC/VA COAST... HOWEVER AS IT
INDUCES WEAK BUT IMPORTANT CYCLOGENESIS JUST OFF THE COAST... THE
FLOW AROUND THIS LOW WILL HELP DRAW THE SURFACE FRONTAL ZONE TO OUR
NORTH (NOW EXTENDING ROUGHLY WEST-EAST JUST NORTH OF THE OH VALLEY
INTO THE NYC AREA) TO THE SOUTH INTO VA/NC LATE WED. THE GFS REMAINS
THE MOST BULLISH IN PUSHING THE FRONTAL ZONE WELL SOUTHWARD INTO THE
SRN CWA... WHEREAS THE NAM (WITH ITS MORE-OFFSHORE LOW) AND THE
ECMWF (MUCH WEAKER LOW) HOLD IT NORTH OF THE NC/VA BORDER OR PERHAPS
DIP IT JUST BARELY INTO OUR NE CWA. HAVE OPTED TO FAVOR THE LATTER
SOLUTION BASED ON THE FAR-NORTH POSITION OF THE PARENT HIGH/COLD AIR
AND LOW CONFIDENCE IN THE GFS`S STRONGER AND MORE WESTWARD LOW.
FORECAST MUCAPE PEAKS AT 750-1500 J/KG ON THE GFS AND 1500-2500 J/KG
ON THE NAM WED AFTERNOON... BUT WITH CONTINUED MODEST DEEP LAYER
SHEAR OF 25-30 KTS. GIVEN THE MOISTURE IN PLACE THOUGH... WILL RAMP
UP POPS TO GOOD CHANCE FOR AFTERNOON INTO EARLY EVENING... TRENDING
BACK DOWN TO 20-30% CHANCE FROM LATE EVENING ONWARD THROUGH WED
NIGHT WITH LOWERING INSTABILITY... BUT WE MAY STILL SEE SCATTERED
SHOWERS CONCENTRATED NEAR AND JUST SOUTH OF THE FRONTAL ZONE... OVER
NRN CWA. VERY WARM THICKNESSES SUPPORT HIGHS OF 77-85 (NE TO SW).
ANOTHER NIGHT OF WARM LOWS IN THE UPPER 50S TO LOWER 60S... WITH
REDUCED CONFIDENCE... AS A FARTHER-SOUTH PENETRATION OF THE FRONT
WOULD MEAN COOLER TEMPS IN THE NE CWA. -GIH
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 255 AM MONDAY...
STILL A LARGE AMOUNT OF UNCERTAINTY WITH THE FIRST PART OF THE LONG
TERM AS IT IS STILL UNCLEAR HOW FAR SOUTH A BACKDOOR COLD FRONT WILL
PUSH ON THURSDAY. HIGH SURFACE PRESSURE APPEARS TO BE TOO FAR TO THE
NORTHEAST TO PRODUCE A STRONG CAD EVENT THIS TIME OF YEAR...BUT IT
MAY HAVE SOME HELP AS LOW PRESSURE OFF THE MID-ATLANTIC COAST COULD
WORK IN TANDEM WITH THE HIGH TO FUNNEL COLD AIR DOWN INTO THE
CAROLINAS. THE STRENGTH AND LOCATION OF THIS LOW COULD BE THE KEY TO
THE FORECAST. AT THIS TIME THE ECMWF AND THE NAM BOTH HAVE THE LOW
FAIRLY FAR OFFSHORE AND WEAKER THAN THE GFS SOLUTION WHICH PUTS THE
LOW MUCH FURTHER SOUTHWEST OFF OF THE NORTHERN OUTER BANKS. THIS
LATE IN THE YEAR WOULD EXPECT THE GFS SOLUTION TO BE TOO STRONG WITH
THE CAD SCENARIO AND THUS WILL FAVOR A NON-GFS SOLUTION...RESULTING
IN WARMER TEMPS FOR THURSDAY THAN MOS GUIDANCE. ONLY LIGHT RAIN
EXPECTED UNTIL LATER IN THE EVENING WHEN MORE RETURN FLOW MOISTURE
MOVES OVER CENTRAL NC. IT SHOULD BE NOTED THAT IF THE GFS SOLUTION
IS CORRECT THE FORECASTED TEMPERATURES WILL BUST ON THE HIGH SIDE.
MODELS COME INTO BETTER AGREEMENT FOR THE END OF THE WEEK WITH A
COLD FRONT PROGGED TO MOVE ACROSS THE STATE FRIDAY EVENING THROUGH
SATURDAY AFTERNOON. WHILE THE EVENT DOES NOT LOOK OVERWHELMING AS
FAR AS SEVERE POTENTIAL IS CONCERNED...THERE WILL BE INSTABILITY
BETWEEN 500-1000 J/KG AND BULK SHEAR VALUES BETWEEN 20-30 KTS WHICH
IS PLENTY FOR CONVECTIVE SHOWERS AND THUNDERSTORMS. ADD SOME
INCREASED FORCING FOR ASCENT AHEAD OF THE FRONT AND THE SEVERE
POTENTIAL INCREASES SLIGHTLY...ENOUGH TO WARRANT A 15% RISK IN THE
DAY 5 CONVECTIVE OUTLOOK FROM SPC.
SURFACE HIGH PRESSURE MOVES IN BEHIND THE FRONT ON SATURDAY NIGHT
WHICH BRINGS IN A COOLER AND DRIER AIRMASS FOR ON SUNDAY AS THE HIGH
SHIFTS OFFSHORE. RAIN RETURNS FOR MONDAY HOWEVER AS A STRONG LOW
PRESSURE SYSTEM OVER THE UPPER MIDWEST USHERS A WARM FRONT OVER
CENTRAL NC FROM THE SOUTHWEST. CONDITIONS WILL REMAIN FAIRLY SOGGY
UNTIL PASSAGE OF THE TRAILING COLD FRONT SOMETIME ON TUESDAY
AFTERNOON.
TEMPERATURES THROUGH THE PERIOD WILL FEATURE HIGHS IN THE MID 70S TO
MID 80S AND LOWS IN THE MID 50S TO MID 60S.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 650 AM TUESDAY...
PRIMARY AVIATION CONCERN NEXT 24 HRS: GOOD CHANCE OF CIGS DROPPING
TO MVFR/IFR THIS MORNING... THEN MVFR CIGS ARE EXPECTED THIS
AFTERNOON. POTENTIAL IFR/LIFR CIGS/VSBYS TOWARD THE END OF THE
FORECAST PERIOD.
AVIATION CONDITIONS WILL BECOME MORE UNSETTLED AND ADVERSE THIS
MORNING. A PASSING DISTURBANCE ALOFT THIS MORNING WILL LEAD TO A
PERIOD OF SHOWERS WITH MVFR VSBYS IN THE FIRST FEW HOURS OF THE
FORECAST... MOVING WEST TO EAST... WITH CIGS LIKELY TO BE
PREDOMINANTLY MVFR/IFR THROUGH MID MORNING. RECOVERY TO MAINLY MVFR
CIGS IS EXPECTED LATER THIS MORNING... THEN THE NORTHWARD MOVEMENT
OF A WARM FRONTAL ZONE THROUGH THE AREA TODAY WITH ANOTHER
DISTURBANCE WILL BRING ANOTHER CHANCE OF SHOWERS WITH MVFR
VSBYS/CIGS MAINLY DURING THE MID TO LATE AFTERNOON. BY EARLY-MID
EVENING... A PERIOD OF VFR CONDITIONS IS POSSIBLE BEHIND THE
DEPARTING DISTURBANCE... BUT EXPECT DEVELOPMENT OF FOG AND LOW
CLOUDS TOWARD MIDNIGHT... LEADING TO AREAS OF IFR/LIFR CONDITIONS IN
THE LAST 6-9 HOURS OF THE TAF VALID PERIOD.
LOOKING BEYOND 12Z WED MORNING: IFR/LIFR CONDITIONS EARLY WED SHOULD
LIFT TO MVFR BY NOON AND TO VFR DURING THE EARLY-MID AFTERNOON.
HEATING AND INSTABILITY WILL LEAD TO SCATTERED SHOWERS AND A FEW
STORMS WED AFTERNOON WITH POTENTIAL SUB-VFR CONDITIONS.
REDEVELOPMENT OF IFR/LIFR FOG/STRATUS IS POSSIBLE WED NIGHT INTO THU
MORNING. ADDITIONAL SHOWERS/STORMS THU AFTERNOON MAY BRING BRIEF SUB-
VFR CONDITIONS. MORE WIDESPREAD AND ORGANIZED SHOWERS AND STORMS ARE
ANTICIPATED AHEAD OF A COLD FRONT APPROACHING LATE FRI. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...ELLIS
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1036 AM EDT TUE APR 7 2015
.SYNOPSIS...
A WEST-TO-EAST ORIENTED FRONTAL BOUNDARY WILL MEANDER NEAR THE
AREA THROUGH THURSDAY NIGHT AND WILL LEAD TO OCCASIONAL CHANCES
FOR SHOWERS AND THUNDERSTORMS. A COLD FRONT WILL MOVE THROUGH LATE
THURSDAY NIGHT INTO FRIDAY. HIGH PRESSURE WILL THEN WORK INTO THE
REGION FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOW CONFIDENCE FORECAST TODAY INTO THIS EVENING IN LOW AMPLITUDE/WEAKLY
FORCED REGIME. 07.12Z KILN RAOB SAMPLED ELEVATED INSTBY /500 J/KG/
ATOP A STABLE BOUNDARY LAYER. WHILE BULK SHEAR VALUES ARE
IMPRESSIVE - EFFECTIVE SHEAR /WHAT UPDRAFTS ARE TRULY FEELING/ IS
QUITE WEAK THUS SHOWERS/STORMS HAVE BEEN WEAK/MODERATE IN
INTENSITY. 25-35KTS OF WSWLY FLOW ABOVE THE BOUNDARY LAYER
CONTINUES MOISTURE TRANSPORT/ISENTROPIC ASCENT THIS MORNING AND IS
PROGGED BY RAP/HRRR TO SLOWLY MIX OUT/WEAKEN AS THE FLOW BACKS
SOMEWHAT. STRONG E-W FRONTAL ZONE WILL CONTINUE TO BE REINFORCED
ACRS CNTL OH/IND WITH FRIGID LAKE ERIE WATERS AND NORTHEAST WINDS
THRU NRN OH REALLY ENHANCING BAROCLINICITY TO THIS FRONT. BY MID
AFTN EXPECT TEMPS TO RANGE ONLY IN THE MID 40S IN FAR NORTHERN
FORECAST AREAS TO 60S AND POSSIBLY 70 IN THE FAR. DEGREE OF
WARMING IS VERY MUCH IN QUESTION ALL AREAS...AS AMPLE CLOUDS ARE
IN PLACE /MANY CIGS AT OR BELOW 1KFT/ WHICH MAKES WARMING
DIFFICULT. IN ADDITION ANVIL BLOWOFF FROM KY/MO CONVECTION WILL
ADD ADDITIONAL MID/HIGH LEVEL MOISTURE THROUGH THE DAY. SO HAVE
BROUGHT TEMPS BACK A LITTLE BIT FROM PVS FORECAST.
WATCHING TWO CLUSTERS OF STORMS RIGHT NOW...ONE NEAR LOUISVILLE
WHICH IS WEAKENING AND A MORE POTENT/ORGANIZED MCS NEAR ST. LOUIS.
EXPECT BOTH CONVECTIVE SYSTEMS TO DIVE SOUTHEAST INTO BETTER
INSTBY/MOISTURE TRANSPORT...AND REMAIN MOSTLY SOUTH OF THE AREA.
THUS...EXPECT A GENERAL DECREASE IN RAIN CHANCES THROUGH THE DAY
THOUGH SHRA/TSRA AREN/T EXPECTED TO TOTALLY DISSIPATE. ISLD-SCT
ACTIVITY TO LIKELY CONTINUE IN THE BROAD MOIST/WARM ADVECTION.
AGREE WITH 13Z SPC UPDATE TO REMOVE MARGINAL SVR THREATS FROM OUR
SOUTH...THOUGH PROXIMITY TO BETTER INSTBY IS IN OUR SOUTHWEST SO
CAN/T RULE OUT A STRONGER STORM OR TWO IN OUR FAR SOUTHWEST LATER
THIS AFTN DEPENDING ON HOW MO/IL CONVECTION EVOLVES. THIS IN LINE
WITH RATHER STABLE HRRR RUNS OVER THE PAST FEW HOURS DEPICTING
CONVECTIVE EVOLUTION FROM MO/IL THROUGH KY WITH MORE ISOLD/SCT
ACTIVITY FURTHER NORTH INTO OHIO AND NEAR THE STATIONARY FRONT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
DISTURBANCE WILL MOVE TO THE EAST THIS EVENING. THIS WILL ALLOW
FOR A DECREASE IN PRECIPITATION CHANCES. BEST CHANCE FOR
PRECIPITATION TONIGHT WILL BE ACROSS NORTHERN PORTIONS OF THE FA
CLOSER TO THE FRONTAL BOUNDARY. AGAIN THERE WILL BE A SHARP
GRADIENT IN TEMPERATURES NORTH AND SOUTH OF THE BOUNDARY. NORTHERN
PORTIONS OF THE FA WILL DROP DOWN INTO THE 40S WHILE SOUTHERN
PORTIONS OF THE FA WILL BE IN THE 60S.
FRONTAL BOUNDARY WILL PUSH JUST NORTH OF THE FA ON WEDNESDAY.
SOUTHERLY FLOW WILL ALLOW FOR TEMPERATURES ACROSS THE FA TO RISE
INTO THE 60S AND 70S. ANOTHER DISTURBANCE WILL WORK THROUGH THE
REGION BRINGING ADDITIONAL SHOWER AND THUNDERSTORM ACTIVITY TO THE
AREA.
A COUPLE MORE ROUNDS OF THUNDERSTORMS ARE EXPECTED TO MOVE THROUGH
WEDNESDAY NIGHT INTO THURSDAY MORNING AND THEN AGAIN THURSDAY
AFTERNOON. SOUTHERLY FLOW PICKS UP FOR THURSDAY WITH GUSTY WINDS
AROUND 30 TO 35 MPH. THIS WILL ALLOW FOR TEMPERATURES TO BE IN THE
70S ACROSS MOST OF THE AREA AND A FEW LOCATIONS NEAR 80 ACROSS FAR
SE PORTIONS OF THE FA.
A COLD FRONT WILL MOVE THROUGH LATE THURSDAY NIGHT INTO FRIDAY
MORNING ALLOWING FOR COOLER TEMPERATURES TO MOVE INTO THE AREA.
PRECIPITATION WILL TAPER OFF DURING THE MORNING HOURS ON FRIDAY
AFTER THE FRONTAL PASSAGE. GUSTY WINDS ARE AGAIN EXPECTED DURING
THE DAY ON FRIDAY. WITH THE DECREASE IN CLOUD COVER FRIDAY NIGHT
AND THE COOL AIRMASS IN PLACE...EXPECT TEMPERATURES TO DROP DOWN
INTO THE 30S AND 40S FRIDAY NIGHT.
WITH SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS OVER THE NEXT FEW
DAYS THERE IS THE POTENTIAL FOR SOME LOCALIZED FLOODING ISSUES.
ALSO...ALTHOUGH WIDESPREAD SEVERE WEATHER IS NOT EXPECTED AT THIS
TIME CANNOT RULE OUT ISOLATED STRONG TO SEVERE STORMS THE NEXT FEW
DAYS.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
SATURDAY...SURFACE HIGH PRESSURE BUILDS INTO THE AREA. COOLER
WEATHER WILL RETURN WITH HIGHS RANGING FROM THE MID 50S NORTH THE
LOWER 60S SOUTH ON SATURDAY.
FOR SUNDAY INTO MONDAY...HIGH PRESSURE IS FORECAST TO MOVE EAST. A
WARM FRONT WILL LIFT TOWARD THE OHIO VALLEY BY SUNDAY NIGHT.
THEREAFTER...A COLD FRONT WILL APPROACH THE REGION FROM THE WEST
LATE MONDAY. WITH RETURN...MOIST FLOW...THE THREAT FOR
SHOWERS/STORMS WILL ONCE AGAIN INCREASE. TEMPERATURES WILL WARM TO
ABOVE NORMAL READINGS ONCE AGAIN.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
INITIAL ROUND OF CONVECTION WILL MOVE EAST OF THE TERMINALS EARLY
IN THE TAF PERIOD. EXPECT IFR CEILINGS TO SPREAD IN BEHIND THIS
ACTIVITY EXCEPT IN THE COLUMBUS AREA WHERE IT MAY REMAIN MVFR.
QUITE A BIT OF UNCERTAINTY WHERE AND WHEN ADDITIONAL SHOWERS AND
THUNDERSTORMS WILL OCCUR THROUGH THE DAY. HAVE USED VCTS TO
INDICATE TIMES WHEN CHANCE APPEARS HIGHER AND WILL AMEND TO
INCLUDE A TEMPO GROUP AS WARRANTED. CEILINGS WILL LIFT SOMEWHAT
THROUGH THE DAY ALTHOUGH IT DOES APPEAR THAT CEILINGS WILL REMAIN
MVFR THROUGHOUT. THERE COULD BE SOME BREAKS IN THE CLOUDS AROUND
00Z BUT THESE ARE EXPECTED TO FILL IN OVERNIGHT. CEILINGS WILL
LOWER ONCE AGAIN WITH BOUNDARY LAYER COOLING AND PREVAILING IFR
CEILINGS LOOK POSSIBLE BY LATE IN THE PERIOD. A FRONT WILL SAG
SOUTH TODAY BEFORE STALLING AND LIFTING BACK NORTH TONIGHT. SOME
UNCERTAINTY HOW FAR SOUTH THIS GETS BUT IT SEEMS LIKELY THAT KDAY
TO KCMH/KLCK TERMINALS WILL HAVE A WIND SHIFT. BUT WIND SPEEDS
WILL BE LESS THAN 10 KT.
OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES ARE LIKELY WEDNESDAY
MORNING. THUNDERSTORMS POSSIBLE WEDNESDAY INTO FRIDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...NOVAK
NEAR TERM...BINAU
SHORT TERM...NOVAK
LONG TERM...HICKMAN
AVIATION...
AREA FORECAST DISCUSSION
NWS PORTLAND
900 AM PDT TUE APR 7 2015
.SYNOPSIS...A LOW PRES OFF THE S OREGON COAST TUE MORNING WILL MOVE
S AND THEN E TODAY AND TONIGHT...MOVING INLAND ACROSS NORTHERN CA
AND NV. ANOTHER WEAK TROUGH OF LOW PRES ALOFT WILL MOVE S OVER
EASTERN WA AND OREGON WED AS A SURFACE RIDGE OF HIGH PRES
STRENGTHENS ALONG THE COAST. THE HIGH WILL MOVE INLAND WED NIGHT AND
THU. THE NEXT PACIFIC FRONTAL SYSTEM IS EXPECTED TO MOVE DOWN FROM
THE GULF OF AK AND PUSH INLAND FRI AND FRI NIGHT.
&&
.UPDATE...A LOW OFFSHORE CONTINUES TO BRING BANDS OF RAIN ACROSS THE
AREA TODAY. THE FIRST BAND NOW OVER THE NORTHERN OREGON ZONES THIS
MORNING CONTINUES TO PERSIST SO HAVE ADJUSTED FORECAST TO MATCH.
MODELS SHOW THIS BAND WEAKENING THIS AFTERNOON AS ANOTHER DEFORMATION
BAND NOW SEEN IN ITS EARLY STAGES ON THE SE QUADRANT OF THE LOW OFF
THE NORTHERN CALIFORNIA COAST.MONDAYS MODELS HAD THE MAIN FOCUS OF
THE PCPN WITH THIS BAND OVER EASTERN LINN AND LANE COUNTY FOR THIS
AFTERNOON AND TONIGHT.THIS MORNING SOME MODELS LIKE THE HRRR ARE
FOCUSING THE HEAVIER PCPN FURTHER NORTH FOR THIS EVENING SO SOME
ADJUSTMENTS MAY BE NEEDED TO THE FORECAST. IF THE HRRR IS CORRECT THE
HEAVIER SNOWFALL IN THE CASCADES MAY VERY WELL BE IN THE NORTH
CASCADES VS. THE CENTRAL CASCADES. MODELS GENERALLY AGREE IN
WEAKENING THE BAND LATE TONIGHT AND WED.
PREVIOUS DISCUSSION...
SHORT TERM...MAIN UPPER LOW SEEN IN WATER VAPOR PICTURES EARLY TUE
MORNING WAS NEAR 42N 128W...STILL MOVING SLOWLY S. A WEAKENING
DEFORMATION BAND OF LIGHT RAIN REMAINED ACROSS SW WA AND THE EXTREME
NW CORNER OF OREGON...AND IS EXPECTED TO CONTINUE TO FIZZLE OUT THIS
MORNING. WHILE THE FOCUS FOR PRECIPITATION WITH THIS LOW REMAINS TO
THE S...SOME SHOWERS EXPECTED TO CONTINUE TO ROTATE AROUND THE N
PART OF THE LOW TODAY AND TONIGHT AS THE LOW TURNS E AND MOVES
INLAND ACROSS NORTHERN CA. MODELS GENERALLY SHOWING AN ENHANCED AREA
OF PRECIPITATION OVER THE SE PART OF THE FORECAST AREA LATE TODAY
AND INTO TONIGHT...GENERALLY OVER THE OREGON PART OF THE CASCADES S
OF MT JEFFERSON. GFS AND NAM SUGGEST THE ENHANCED PRECIPITATION IS
RELATED TO AN AREA OF DEFORMATION ON THE N SIDE OF THE LOW AS IT
MOVES BY TO THE S. GIVEN THE GOOD AGREEMENT IN MODELS SHOWING THIS
QPF FIELD...AND WITH SNOW LEVELS STILL AT OR A LITTLE BELOW PASS
LEVELS...WILL GO AHEAD WITH A WINTER WEATHER ADVISORY FOR SNOW THERE
ABOVE 4500 FT LATE THIS AFTERNOON AND CONTINUING PAST MIDNIGHT.
MOST OF THE PRECIPITATION ASSOCIATED WITH THE UPPER LOW IS EXPECTED
TO END WED MORNING AS IT MOVES OFF TO THE E...BUT ANOTHER TROUGH
COMING DOWN FROM THE N WILL BRING A LESSER THREAT FOR SHOWERS GOING
WED AFTERNOON AND EVENING. THIS UPPER TROUGH HAS AN INLAND TRACK
COMING DOWN FROM BC WHICH IS NORMALLY DRY...BUT A LOW LEVEL ONSHORE
FLOW WILL KEEP ENOUGH MOISTURE AVAILABLE TO GENERATE AN UNSTABLE
LAYER IN THE LOW TO MID LEVELS WED AFTERNOON. A LOOK AT MODEL
SOUNDINGS AT 00Z THU INDICATES UNSTABLE LAYER MAY BE MARGINALLY DEEP
ENOUGH TO SUPPORT A SLIGHT CHANCE FOR THUNDER OVER THE CASCADES WED
AFTERNOON...SO WILL MAINTAIN THE SLIGHT CHANCE THERE BUT PULL IT
FROM AREAS FURTHER W. WILL CONTINUE WITH A SLIGHT CHANCE FOR SHOWERS
AGAIN THU AFTERNOON OVER THE CASCADES AS THE WEAK TROUGH REMAINS
OVER THE AREA IN AT LEAST SOME MODELS. OTHERWISE RISING HEIGHTS
SUGGESTS A WARMER DAY FOR THU.
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS. THURSDAY NIGHT
THROUGH SUNDAY...WHAT RESIDUAL SHOWERS THAT FORM THURSDAY AFTERNOON
WILL CLEAR THURSDAY NIGHT. THE MODELS ARE COMING INTO BETTER
AGREEMENT WITH THE NEXT FRONT BEGINNING TO MOVE ONSHORE AND SPREAD
RAIN ONSHORE ON FRIDAY...AND MOVING THROUGH SOUTHWEST WASHINGTON AND
NORTHWEST OREGON FRIDAY NIGHT. SNOW LEVELS ARE FORECAST TO RISE
ABOVE THE CASCADE PASSES FRIDAY BEFORE FALLING BELOW THE PASSES
FRIDAY NIGHT AND STAYING WELL BELOW THE PASSES OVER THE WEEKEND AS
BRISK ONSHORE FLOW SPREADS COOL SHOWERY AIR ONSHORE AND LIKELY GIVES
THE CASCADES ANOTHER GOOD DOSE OF SNOW. THE ECMWF MODEL HAS THE
BRUNT OF THE ONSHORE FLOW FARTHER NORTH THAN THE GFS AND NAM12
MODELS...SO THAT IS THE MAIN UNCERTAINTY ABOUT CASCADE SNOW FOR THIS
WEEKEND AT THIS POINT. ANOTHER PACIFIC FRONT IS POSSIBLE EARLY NEXT
WEEK...CONTINUING THE CURRENT EARLY SPRING PATTERN. TOLLESON &&
.AVIATION...A WEAK LOW PRESSURE OFF THE CENTRAL OREGON COAST WILL
PUSH ASHORE NEAR THE CALIFORNIA/OREGON STATE LINE THIS
EVENING. THIS SHOULD RESULT IN MAINLY VFR CONDITIONS WITH OCCASIONAL
LIGHT RAIN SHOWERS MVFR CONDITIONS ALONG THE COAST...PARTICULARLY
AT KONP. IN ADDITION...WEAK NORTHERLY FLOW IN THE SOUTHERN
WILLAMETTE VALLEY WILL PRODUCE IFR AND MVFR CONDITIONS AT KEUG
THIS MORNING. A BAND OF HEAVIER PRECIPITATION IS EXPECTED TO FORM
OVER THE CENTRAL OREGON CASCADES AND MAY ALSO MOVE CLOSE ENOUGH
TO KSLE AND KEUG TO BRING MVFR CONDITIONS TO THESE TERMINALS AFTER
00Z WEDNESDAY. THERE IS SOME CHANCE THIS BAND OF PRECIP WILL MOVE
NORTH AND AFFECT THE PDX AREA TERMINALS LATE THIS AFTERNOON AND
EVENING.
KPDX AND APPROACHES...EXPECT PRIMARILY VFR CONDITIONS THROUGH 12Z
WEDNESDAY. MODELS ARE STARTING TO SHOW A BAND OF SHOWERS NEAR THE
TERMINAL LATE THIS AFTERNOON AND EVENING WHICH COULD PRODUCE MVFR
CONDITIONS FOR A NUMBER OF HOURS. BOWEN/NEUMAN
&&
.MARINE...A WEAK LOW PRESSURE SYSTEM WILL SLOWLY DRIFT SOUTHWARD
THIS MORNING AND PUSH ASHORE NEAR THE CALIFORNIA/OREGON BORDER
LATE TODAY. THIS WILL RESULT IN WEAKENING WINDS THROUGH THE
MORNING HOURS AND WINDS AT BUOY 29 ARE ALREADY DECREASING. BUILDING
HIGH PRESSURE OVER THE WATERS SHOULD THEN BRING MORE TRANQUIL WIND
AND SEAS THROUGH THURSDAY NIGHT.
A QUICK MOVING FRONT WILL LIKELY BRING A BURST OF 25 TO 35 KT
SOUTHERLY
WIND GUSTS ON FRIDAY. A LARGE FETCH OF GUSTY 25 KT WESTERLY WINDS
IN ITS WAKE WILL AID IN THE ARRIVAL OF A 10 TO 15 FT SWELL OVER
THE WEEKEND.
HIGH PRESSURE LOOKS TO RETURN LATE IN THE WEEKEND BEFORE ANOTHER
SIMILAR STORM SYSTEM ARRIVES EARLY NEXT WEEK...AND POSSIBLY PUSHES
SEAS WELL ABOVE 10 FT ONCE AGAIN. BOWEN/NEUMAN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY FROM 2 PM THIS AFTERNOON TO 3 AM PDT
WEDNESDAY FOR CASCADES IN LANE COUNTY-NORTHERN OREGON
CASCADES.
WA...NONE.
PZ...NONE.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
456 AM MDT TUE APR 7 2015
.SHORT TERM...(TODAY THROUGH THURSDAY NIGHT)
ISSUED AT 159 AM MDT TUE APR 7 2015
IF YOU ARE AN AFICIONADO OF THE GAMUT OF WEATHER PHENOMENON...YOU
WILL LOVE THE NEXT FEW DAYS.
TODAY...AS EXPECTED BY OUR FORECAST TEAM...LOW CLOUDS AND FOG HAVE
DEVELOPED ALONG AND EAST OF THE LARAMIE RANGE AND INTERSTATE 25
CORRIDOR WITH MOIST LOW LEVEL UPSLOPE. HAVE FOLLOWED THE CURRENT
AREAL FOG COVERAGE AND BOUNDARY LAYER PROGS FOR PAINTING FOG AREAS
THIS MORNING.
FOR THIS AFTERNOON...ATTENTION THEN SHIFTS TO AREAL COVERAGE OF
SHOWERS AND THUNDERSTORMS. DECENT SOUTHWEST FLOW ALOFT WITH WEAK
SHORTWAVE TROUGH MOVING NORTHEASTWARD OVER OUR COUNTIES NEAR PEAK
HEATING...WITH LOW LEVEL EAST SOUTHEASTERLIES ADVECTING LOW LEVEL
MOISTURE TO THE BASE OF THE LARAMIE RANGE. BASED ON THE LOCATIONS OF
THE 850 MB AND 700 MB THETA-E RIDGES...FROM DOUGLAS TO CHEYENNE TO
SIDNEY AND UPWARD VERTICAL MOTION...EXPECT ISOLATED TO SCATTERED
AFTERNOON SHOWERS ALONG THIS THETA-E RIDGE...MOST NUMEROUS FROM
DOUGLAS TO WHEATLAND WHERE UVV AND THETA-E RIDGING IS MOST
COINCIDENT. ENOUGH INSTABILITY FOR A FEW THUNDERSTORMS AS WELL.
TONIGHT...FLOW ALOFT BACKS IN ADVANCE OF THE APPROACHING STRONGER
SHORTWAVE TROUGH...WITH MOIST LOW LEVEL UPSLOPE SOUTHEAST WINDS
CONTINUING TO ADVECT MOISTURE ACROSS OUR EASTERN PLAINS ALONG AND
EAST OF INTERSTATE 25. WILL SEE AN INCREASE IN AREAL COVERAGE OF FOG
ALONG AND EAST OF INTERSTATE 25...AND MAY EVEN SEE SOME AREAS OF
DENSE FOG DEPENDING ON THE AREAL COVERAGE OF LOW CLOUDS AND IF
ISOLATED SHOWERS ARE MINIMIZED.
WEDNESDAY...WOULD NOT BE SURPRISED TO SEE OUR TEAM ISSUE OUR FIRST
SEVERE THUNDERSTORM WARNING OF THE SEASON IN THE AFTERNOON OR
EVENING. IMPRESSIVE AND ROBUST SHORTWAVE TROUGH ALOFT MOVES OVER
CENTRAL WYOMING IN THE AFTERNOON...WITH AN IMPRESSIVE INVERTED
SURFACE TROUGH AXIS ACROSS OUR FAR EASTERN WYOMING COUNTIES. QUITE
PRONOUNCED 850 MB THETA-E RIDGE AXIS EXTENDS ALONG AND JUST WEST OF
THE WYOMING AND NEBRASKA STATE LINE IN THE AFTERNOON...WITH ROARING
LEFT FRONT QUADRANT OF THE 300 MB JET STREAKING IN FROM SOUTHWEST TO
NORTHEAST. ALTHOUGH CAPE WILL NOT BE OVERLY IMPRESSIVE...WITH
PROGGED 500-300 MB AND 700-500 MB QUASIGEOSTROPHIC LIFT...TIMING
COINCIDENT WITH PEAK HEATING...AND SHEAR...WE EXPECT SCATTERED
AFTERNOON THUNDERSTORMS EAST OF INTERSTATE 25...WITH A FEW STORMS
BECOMING STRONG TO SEVERE FROM LATE AFTERNOON THROUGH EARLY
EVENING AND THE BEST THREAT FOR STRONGEST THUNDERSTORMS FROM LUSK
TO TORRINGTON TO PINE BLUFFS IN THE AFTERNOON...THEN INTO THE
PANHANDLE IN THE EVENING. WIDESPREAD SHOWERS FOCUSED ALONG THE
INSTABILITY AXIS IN THE AFTERNOON EAST OF INTERSTATE 25.
WEDNESDAY NIGHT...WITH PLENTY OF LOW AND MID LEVEL MOISTURE AS
FUEL...AND THE ENERGIZED PROGRESSIVE SHORTWAVE TROUGH ALOFT MOVING
OVERHEAD...ALONG WITH A POTENT PACIFIC ORIGIN COLD FRONT PASSAGE AND
BAROCLINIC BAND...WILL SEE WIDESPREAD SHOWERS EAST OF I-25 WITH
LESSER COVERAGE WEST OF I-25. PRECIPITATION WILL SWITCH OVER TO SNOW
WITH MINIMAL ACCUMULATIONS AT LOWER ELEVATIONS...THOUGH WE MAY SEE
2 TO 5 INCHES OF SNOW OVER THE SNOWY RANGE AND SIERRA MADRES AND
NORTHERN LARAMIE RANGE. WILL SEE AREAS OF FOG DEVELOP...THOUGH
MINIMIZED BY THE WIDESPREAD SNOW SHOWERS AFTER MIDNIGHT. WINDY AND
CHILLY. TOTAL SNOWFALL OF 3 TO 7 INCHES EXPECTED BY FRIDAY MORNING
OVER OUR NORTHERN LARAMIE...SNOWY AND SIERRA MADRE RANGES.
THURSDAY...AREAL COVERAGE OF SHOWERS WILL WANE IN THE MORNING AND
EARLY AFTERNOON AS THE SHORTWAVE TROUGH ALOFT DYNAMICS MOVE FAR TO
OUR EAST...THOUGH IT WILL BE A WINDY AND COOL EARLY APRIL DAY WITH
MAXIMUM TEMPERATURES IN THE 40S AT LOWER ELEVATIONS AND 30S OVER THE
MOUNTAINS...PER PROGGED LOW AND MID LEVEL GRADIENTS...700 MB
TEMPERATURES AND THICKNESSES.
THURSDAY NIGHT...ANOTHER WEAKER SHORTWAVE TROUGH ALOFT MOVES OVER
WYOMING WITH ONLY WEAK UPWARD VERTICAL MOTION PRODUCING ISOLATED TO
SCATTERED SHOWERS OVER OUR NORTHERN LARAMIE...SNOWY AND SIERRA MADRE
RANGES. DRY ELSEWHERE.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 330 AM MDT TUE APR 7 2015
WEAK DEPARTING UPPER LEVEL TROUGH EARLY FRIDAY COULD BRING SOME
ISOLATED SHOWERS TO THE MOUNTAINS THROUGH THE AFTERNOON HOURS.
MOST LOCATIONS THOUGH SHOULD REMAIN DRY. 700MB TEMPERATURES ON THE
REBOUND...CLIMBING TO +4C BY SATURDAY. SHOULD SEE UPPER 60S PRETTY
COMMON SATURDAY IN THE PANHANDLE AND LOW 60S OUT WEST.
GFS AND ECMWF SHOWING A WINDY PERIOD AS 700MB WINDS CONTINUE TO
INCREASE. THIS IN RESPONSE TO A LOW PRESSURE SYSTEM TRACKING
ACROSS THE SOUTHERN CANADIAN PROVINCES SUNDAY INTO MONDAY. IN
FACT...GFS FORECAST 50+KTS AT 700MB MONDAY NIGHT...SO WE COULD BE
LOOKING AT WIND HEADLINES FOR OUR WIND PRONE AREAS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 454 AM MDT TUE APR 7 2015
LATEST HRRR GUIDANCE USED FOR THE 12Z TAFS. IFR/LIFR CONDITIONS
FOR MUCH OF THE MORNING. DID STRAY FROM HRRR GUIDANCE ON KCYS A
LITTLE. DO THINK LOW CONDITIONS WILL STAY IN A LITTLE LONGER HERE
AS SOUTH TO SOUTHEAST UPSLOPE WINDS PREVAIL. LOOK FOR A REPEAT OF
STRATUS AND FOG TONIGHT FOR THE NEBRASKA PANHANDLE AND AREAS EAST
OF THE LARAMIE RANGE.
&&
.FIRE WEATHER...
ISSUED AT 159 AM MDT TUE APR 7 2015
FOR TODAY...SOME CONCERN WEST OF INTERSTATE 25 WHERE
HUMIDITIES IN PORTIONS OF CARBON COUNTY WILL RANGE FROM 15 TO 20
PERCENT IN THE AFTERNOON WITH GUSTY SOUTHWEST WINDS. MINIMAL
CONCERNS ELSEWHERE DUE TO HIGHER HUMIDITIES.
WEDNESDAY...HUMIDITIES WILL BE ABOVE CRITICAL LEVELS...THOUGH FIRE
WEATHER INTERESTS WILL NEED TO WATCH FOR LIGHTNING STRIKES FROM
ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS ALONG AND
EAST OF INTERSTATE 25.
HUMIDITIES DECREASING AGAIN OVER THE WEEKEND WITH SOME GUSTY WINDS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...RUBIN
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...RUBIN
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
122 PM CDT TUE APR 7 2015
.AVIATION...07/18Z TAF CYCLE
MVFR CIGS WL BE NOTED ACRS THE FA THRU MOST OF THIS AFTN. HOWEVER...
INCRSG LOW LVL MIXING WL HELP CIGS TO GRADUALLY LIFT TO VFR LVLS
LATER THIS AFTN AND LINGER INTO THIS EVENING. LOW CLOUDS WL THEN
RETURN LATER TNGT...WITH VFR/MVFR CONDS EXPECTED. OUTSIDE AN ISOLD
SHRA/TSRA THRU THIS EVENING...NO ORGANIZED CONVECTION IS
ANTICIPATED TO AFFECT THE FA THRU WED MRNG. /44/
&&
.PREV DISCUSSION... /ISSUED 1009 AM CDT TUE APR 7 2015/
UPDATE...
NO SIGNIFICANT CHANGES MADE FOR THE MORNING UPDATE. RADAR TRENDS
SHOW THAT PRECIPITATION IS ABOUT TO COME TO AN END ACROSS THE
FORECAST AREA...WITH ONLY SOME ISOLATED THUNDERSTORMS LEFT UP
AROUND THE BATESVILLE AREA AS OF 10 AM. BY NOON ALL RAIN WILL HAVE
EXITED AND EXPECT DRY CONDITIONS FOR THE REST OF TODAY. ADJUSTED
POPS THROUGH THE MORNING TO REFLECT THESE TRENDS...AND HAVE NO
PRECIP MENTIONED FOR THE AFTERNOON PERIOD. TEMPERATURES LOOK ON
TRACK SO NO ADJUSTMENTS THERE EITHER.
PREV DISCUSSION... /ISSUED 621 AM CDT TUE APR 7 2015/
AVIATION...
SCATTERED LIGHT SHOWERS AND A FEW THUNDERSTORMS WILL CONTINUE THIS
MORNING...WITH PREVAILING CONDITIONS MVFR TO IFR. CONDITIONS WILL
IMPROVE LATE THIS MORNING AND INTO THE AFTERNOON...WITH MOST AREAS
VFR AROUND OR A LITTLE AFTER 18Z. MVFR LOW CLOUDS AND FOG WILL
RETURN LATE TONIGHT...MAINLY AFTER 06Z. WINDS WILL BE SOUTHERLY
AROUND 10 KNOTS TODAY...WITH HIGHER GUSTS. TAS ALREADY OUT.
PREV DISCUSSION... /ISSUED 333 AM CDT TUE APR 7 2015/
SHORT TERM...TODAY THROUGH FRIDAY
SHOWERS AND A FEW THUNDERSTORMS DEVELOPED ACROSS THE STATE DURING
THE OVERNIGHT HOURS WITH SOME PATCHY FOG DEVELOPING. HRRR SUGGESTS
THESE SHOWERS WILL INCREASE IN COVERAGE THROUGH THE EARLY MORNING
HOURS AND KEEP RAIN CHANCES IN THE FORECAST THROUGH THE LATE
MORNING...GENERALLY ACROSS THE EASTERN HALF OF THE STATE.
OTHERWISE...PRECIPITATION WILL BE LIMITED ON TUESDAY WITH A STRONGLY
CAPPED ATMOSPHERE IN PLACE. THE BEST CHANCES FOR
PRECIPITATION...RELATIVELY SPEAKING...WILL BE ACROSS NORTHERN
ARKANSAS...BUT EVEN STILL NOT CONFIDENT ENOUGH TO GO ABOVE SLIGHT
CHANCES. WINDS WILL BE A BIT ON THE STRONG SIDE TODAY...BUT NOT
STRONG ENOUGH TO WARRANT A LAKE WIND ADVISORY.
WEDNESDAY...PRECIPITATION CHANCES WILL SOMEWHAT INCREASE...MAINLY
ACROSS WESTERN ARKANSAS AS A COLD FRONT SLOWLY MARCHES TOWARD THE
STATE. ATMOSPHERE STILL LOOKS TO BE FAIRLY CAPPED ON
WEDNESDAY...HOWEVER UPPER LEVEL RIDGE WILL BEGIN TO PUSH TO THE EAST
ALLOWING TEMPERATURES ALOFT TO SOMEWHAT COOL AND SOMEWHAT WEAKENING
THE CAP.
THURSDAY CONTINUES TO LOOK LIKE THE BEST CHANCE FOR SEVERE WEATHER
ACROSS THE CWA. SURFACE LOW PRESSURE WILL TRACK FROM COLORADO
THROUGH IOWA...DRAGGING ITS ASSOCIATED COLD FRONT THROUGH THE STATE.
MODEL SOUNDINGS TO CONTINUE TO SHOW THE POTENTIAL FOR SEVERE WEATHER
IN THE STATE WILL ALL MODES POSSIBLE. THE COLD FRONT ITSELF WILL NOT
ENTER THE STATE UNTIL 00Z...AND PUSH THROUGH THE STATE BY 12Z
FRIDAY. WITH AMPLE MOISTURE IN PLACE AFTER QUITE A FEW DAYS OF
STRONG SOUTHERLY FLOW...HEAVY RAIN CONTINUES TO BE A CONCERN WITH
THIS SYSTEM.
HIGH PRESSURE AND DRY WEATHER WILL MOVE INTO THE STATE FOR
FRIDAY...WITH THE FRONT STALLING JUST TO THE SOUTH OF THE STATE.
TEMPERATURES WILL RETURN TO NEAR NORMAL LEVELS.
LONG TERM...FRIDAY NIGHT THROUGH MONDAY
HIGH PRESSURE WILL BE MOVING THROUGH THE AREA ON FRIDAY NIGHT...WITH
THE FRONT STALLED OUT JUST TO THE SOUTH OF THE REGION. THE HIGH WILL
MOVE EASTWARD ON SATURDAY...WITH RETURN FLOW SETTING UP AS THE FRONT
BEGINS TO BACK NORTHWARD. SHOWERS AND THUNDERSTORMS WILL RETURN TO
THE FORECAST...WITH THE HIGHEST CHANCES ON SUNDAY AND SUNDAY NIGHT...
AS THE WARM FRONT MOVES THROUGH...ALONG WITH AN UPPER TROUGH WITH A
BIT OF A NEGATIVE TILT. EXTENDED RANGE MODELS ARE SHOWING A SURFACE
LOW DEVELOPING SUNDAY NIGHT INTO MONDAY...DRAGGING A COLD FRONT INTO
THE REGION DURING THE DAY.
IF THE AFOREMENTIONED SCENARIO PANS OUT...SEVERE THUNDERSTORMS MAY
BE POSSIBLE. ALSO...WITH GULF AND PACIFIC MOISTURE LINING UP...
PRECIPITABLE WATER VALUES WILL BE APPROACHING TWO INCHES. THUS...
HEAVY RAINFALL WOULD BE A POSSIBILITY AS WELL. WILL CONTINUE TO
MONITOR THIS POTENTIAL HAZARDOUS WEATHER SETUP...AND ADJUST
SUCCESSIVE FORECASTS ACCORDINGLY. ONE THING THAT IS CONCERNING IS
THAT...THOUGH THE SMALL DETAILS DIFFER TO VARYING DEGREES...THE
MODELS ARE IN REMARKABLY GOOD AGREEMENT FOR SIX DAYS OUT. STAY
TUNED.
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
1005 AM PDT TUE APR 7 2015
.UPDATE...
CURRENT FORECAST IS GENERALLY ON THE RIGHT TRACK WITH NO
SIGNIFICANT CHANGES PLANNED THIS MORNING.
SO FAR THIS MORNING, THE MAIN IMPACTS OF THE SNOW BAND OVER
CALIFORNIA HAVE BEEN LIMITED TO AREAS NEAR AND WEST OF THE SIERRA
CREST. CHAIN CONTROLS ARE CURRENTLY IN PLACE ON I-80 OVER DONNER
SUMMIT AND CA 88 OVER CARSON PASS. FOR THE REMAINDER OF THE
MORNING, THE STEADY SNOW BAND WILL BEGIN TO DECREASE IN COVERAGE WITH
SOME AREAS OF MOISTURE BREAKING OFF AND SPREADING INTO WESTERN NV.
AIR MASS IN LOWER ELEVATIONS IS STILL RELATIVELY DRY SO LITTLE OR
NO MEASURABLE PRECIP IS EXPECTED ACROSS THE RENO-CARSON CITY
VICINITY THROUGH MIDDAY.
FOR THIS AFTERNOON AS THE COLD POOL ALOFT MOVES INTO CENTRAL CA,
CONVECTION WILL INCREASE WITH BANDS OF SNOW SHOWERS SPREADING OVER
THE SIERRA. ROAD SURFACES WILL LIKELY BECOME WET OR SLUSHY NEAR
THE SIERRA FROM MIDDAY THROUGH MID AFTERNOON AS HIGHER SUN ANGLES
ASSIST IN MELTING OFF THE SNOW WHICH HAS ALREADY FALLEN. SOME OF
THIS SNOW SHOWER ACTIVITY WILL CONTINUE INTO THE EVENING WITH
POTENTIAL FOR MORE TRAVEL IMPACTS AS ROAD SURFACE TEMPS DECREASE.
FOR WESTERN NV, THE TRANSITION TO A CONVECTIVE REGIME WILL LEAD TO
INCREASED SHOWER DEVELOPMENT WITH ISOLATED THUNDERSTORMS POSSIBLE
WITH SMALL HAIL OR GRAUPEL OCCURRING WITH STRONGER CELLS. THE
LATEST HRRR AND NAM GUIDANCE SHOW CONDITIONS A LITTLE MORE
FAVORABLE FOR THUNDER IN AREAS NORTH AND EAST OF A RENO-FALLON
LINE BETWEEN 1 AND 7 PM.
FARTHER SOUTH IN MONO COUNTY, THE MONO LAKE WEB CAMERA SHOWED A
SMALL AREA OF BLOWING DUST WITH A WIND SENSOR NEAR THE LAKE
SHOWING SPEEDS IN THE 20-30 MPH RANGE. SOME GUSTS TO 40 MPH WILL
BE POSSIBLE ALONG HIGHWAY 395 BEFORE SHOWERS SPREAD ACROSS THE
COUNTY LATER TODAY. MJD
&&
.PREVIOUS DISCUSSION... /ISSUED 247 AM PDT TUE APR 7 2015/
SYNOPSIS...
LOW PRESSURE WILL BRING SNOW AND SLICK ROAD CONDITIONS TO THE
SIERRA TODAY INTO WEDNESDAY MORNING, WITH SNOW AND RAIN SHOWERS IN
LOWER ELEVATIONS. ISOLATED THUNDERSTORMS ARE POSSIBLE THIS
AFTERNOON. TEMPERATURES WILL REMAIN BELOW NORMAL THROUGH MIDWEEK,
FOLLOWED BY A WARMING AND DRYING TREND LATER IN THE WEEK.
SHORT TERM...
A COLD SPRING STORM IS BEGINNING TO PUSH A BAND OF PRECIPITATION
ACROSS THE NORTHERN CALIFORNIA COAST EARLY THIS MORNING. THIS BAND
OF PRECIPITATION WILL PUSH EASTWARD AND PROVIDE ACCUMULATING SNOW IN
THE SIERRA LATER THIS MORNING THROUGH EARLY WEDNESDAY MORNING. WINTER
WEATHER ADVISORIES ARE IN PLACE ACROSS THE EASTERN SIERRA WHERE SNOW
COVERED ROADS AND CHAIN RESTRICTIONS ARE EXPECTED THROUGH THE
SIERRA. SNOW ACCUMULATIONS THROUGH WEDNESDAY MORNING ACROSS THE
EASTERN SIERRA ARE GENERALLY IN THE 6-12" RANGE FOR LOCATIONS ABOVE
7,000 FEET WITH ABOUT 3-6" THROUGH THE TAHOE BASIN AND AREAS WEST OF
HWY 395 THROUGH MONO COUNTY. INSTABILITY WILL INCREASE THROUGH THE
DAY AS THE COLD CORE OF THE UPPER LOW SETTLES ACROSS THE REGION.
THIS WILL PROMOTE THE DEVELOPMENT OF LOCALIZED AREAS OF HEAVIER
SNOWFALL WITHIN STRONGER CELLS, SNOW PELLETS, SMALL HAIL, AND
ISOLATED LIGHTNING STRIKES.
ACROSS WESTERN NEVADA, SHOWERS LOOK TO PUSH INTO THE AREA AFTER NOON
WITH A MIX OR RAIN AND SNOW EXPECTED AS SNOW LEVELS HOVER AROUND
4,500-5,000 FEET THROUGH THE DAY. LITTLE TO NO ACCUMULATION IS
EXPECTED ACROSS WESTERN NEVADA VALLEYS WITH HIGH SUN ANGLES IN
PLACE, BUT LOCATIONS ABOVE 5,000 MAY SEE BETTER CHANCES FOR SOME
SLUSHY ACCUMULATIONS. SHOWERS WILL LINGER THROUGH THE EVENING WITH
THE BULK THE HEAVIER PRECIPITATION ENDING BY LATE AFTERNOON. TRAVEL
IMPACTS ARE POSSIBLE THROUGH TONIGHT AS SHOWERS DIMINISH BUT
POTENTIAL INCREASES FOR SNOW TO STICK ON ROADWAYS ACROSS THE SIERRA.
BREEZY CONDITIONS WILL ACCOMPANY THE STORM WITH SOUTHERLY WINDS
SHIFTING WEST BY EARLY AFTERNOON THEN NORTHWEST THIS EVENING AS THE
COLD FRONT PUSHES ACROSS THE REGION. WILL GENERALLY SEE GUSTS IN THE
30-35 MPH RANGE WITH GUSTS ACROSS THE SIERRA CREST AROUND 60-70 MPH.
CHOPPY CONDITIONS EXPECTED ACROSS AREAS LAKES WITH WINDS LESSENING
WITH THE ONSET OF PRECIPITATION.
BY WEDNESDAY MORNING, THE MAIN UPPER LOW SHIFTS EASTWARD ACROSS UTAH
WITH ONLY A FEW LIGHT LINGERING SHOWERS EXPECTED. SOME BANDED
PRECIPITATION IS POSSIBLE ON THE BACKSIDE OF THE LOW BUT IT LOOKS TO
BE MAINLY CONFINED TO FAR NORTHEASTERN NEVADA WITH SOME SHOWERS
EXTENDING AS FAR WEST AS FAR NORTHERN WASHOE COUNTY AND THE SURPRISE
VALLEY. SHOWERS DIMINISH BY WEDNESDAY EVENING AS A SHORTWAVE BEGINS
TO BUILD ACROSS THE AREA BY THURSDAY WHERE DAYTIME TEMPERATURES
WILL REBOUND BACK INTO THE LOWER 60S ACROSS WESTERN NEVADA AND MID
50S FOR THE SIERRA. FUENTES
LONG TERM...FRIDAY THROUGH MONDAY...
FORECASTER CONFIDENCE IS RISING FOR THE EXTENDED FORECAST AS MODELS
HAVE COME INTO BETTER AGREEMENT OVER THE LAST 24 HOURS SHOWING THE
DEVELOPING PATTERN OVER THE WEST COAST. GFS CONTINUES TO TREND LOWER
HEIGHTS OVER NORTHERN CA/NV FOR THE WEEKEND AS THE NORTHERN BRANCH
OF A SPLIT JET DIVES INTO THE WEST COAST AND ACROSS THE GREAT BASIN.
ECMWF AND GEM ARE IN GOOD AGREEMENT AS WELL, BRINGING A COLD FRONT
ACROSS THE REGION WITH CHANCES OF LIGHT PRECIPITATION. THE MAJORITY
OF THE PRECIP/DYNAMICS WILL REMAIN IN THE PACIFIC NORTHWEST WITH
ONLY A VERY MODEST AMOUNT OF MOISTURE PUSHING NEAR THE CA/NV/OR
BORDER. IN THAT AREA NORTH OF SUSANVILLE, WE EXPANDED THE SLIGHT
CHANCE OF SHOWERS INTO SATURDAY AND KEPT CHANCES IN THROUGH SUNDAY
TO ACCOUNT FOR MODEL DIFFERENCES IN THE TIMING OF THE WAVE.
WE SHOULD BEGIN TO WARM BACK UP SUNDAY-MONDAY AS WEAK RIDGING BUILDS
OVER THE WEST COAST. MODELS CONTINUE TO HINT AT YET ANOTHER TROUGH
DROPPING OUT OF THE GULF OF ALASKA AND INTO THE PAC NW NEXT WEEK,
KEEPING THE ACTIVE WEATHER PATTERN GOING. HOON
AVIATION...
SIGNIFICANT SPRING STORM WILL BE PUSHING INTO THE SIERRA TODAY WITH
LIGHT SHOWERS IN WESTERN NEVADA. IFR CIGS/VIS WILL DEVELOP AROUND
16Z THIS MORNING AROUND THE TAHOE BASIN WITH PERIODS OF MODERATE
SNOW. SHOWERS WILL LINGER THROUGH TONIGHT IN THE SIERRA WITH PERIODS
OF MVFR/IFR.
FOR WESTERN NEVADA, THE BEST POSSIBLE TIME FOR SPILLOVER WILL BE
BETWEEN 18Z-00Z WITH A MIX OF RAIN, SNOW AND SNOW PELLET SHOWERS
POSSIBLE. IN ADDITION, THERE IS A 15 PERCENT FOR THUNDERSTORMS
TODAY, BUT CONFIDENCE IS LOW IN PINPOINTING THE LOCATION OF
WHERE THE STORMS WILL FORM.
ACCUMULATING SNOW IS LIKELY ON RUNWAYS AT KTRK, KTVL, AND KMMH
TODAY, THOUGH IT MAY JUST BE SLUSHY DURING THE MIDDLE PART OF THE
DAY DUE TO THE APRIL SUN ANGLE. MIDDAY WILL BE THE BEST CHANCES FOR
SPILLOVER INTO WESTERN NEVADA, SO IT IS UNLIKELY SNOW WILL ACCUMULATE
ON RUNWAYS AT KRNO OR KCXP.
SOUTHERLY WINDS TOMORROW WILL BECOME WESTERLY BEHIND THE COLD
FRONTAL PASSAGE, WHICH WILL BE APPROXIMATELY BETWEEN 18-21Z. WINDS
MAY GUST AS HIGH AS 25-30 KTS IN VALLEYS WITH 55-60 KTS ACROSS
SIERRA RIDGES. THIS WILL LEAD TO WEAK TO MODERATE MOUNTAIN
TURBULENCE AND A SLIGHT CHANCE OF LOW LEVEL WIND SHEAR ALONG THE
COLD FRONT. DJ/HOON
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...WINTER WEATHER ADVISORY UNTIL 5 AM PDT WEDNESDAY NVZ002.
CA...WINTER WEATHER ADVISORY UNTIL 5 AM PDT WEDNESDAY CAZ071.
WINTER WEATHER ADVISORY UNTIL 5 AM PDT WEDNESDAY CAZ073.
WINTER WEATHER ADVISORY UNTIL 5 AM PDT WEDNESDAY CAZ072.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1102 AM MDT TUE APR 7 2015
.UPDATE...
ISSUED AT 1059 AM MDT TUE APR 7 2015
DRY SOUTHWEST FLOW ALOFT WILL RESULT IN ANOTHER WINDY DAY TODAY.
GUSTY WINDS WERE ALREADY OBSERVED AT MANY VALLEY LOCATIONS AS
ABUNDANT SUNSHINE MIXES OUT THE MORNING INVERSION. THIS MORNING`S
12Z NAM AND GFS MODELS SHOW THE 300 MB UPPER JET LIFTING INTO WY
THIS AFTERNOON AS A SHORTWAVE OVER SRN NV EJECTS NORTHEAST ACROSS NW
UT. WILL HOLD OFF ON VALLEY WIND ADVISORIES FOR TODAY WITH THE JET
LIFTING NORTH AND THE 15Z HIGH-RESOLUTION HRRR AND RAP MODELS
SHOWING WINDS BELOW THE 45 MPH GUST CRITERIA. BUT...GUSTS TO 35-40
MPH SHOULD BE FAIRLY COMMON FOR MANY VALLEYS OF ERN UT AND WRN CO AS
DEEP MIXING PULLS STRONGER WINDS ALOFT TO THE SURFACE. RED FLAG
WARNINGS FOR FIRE WEATHER LOOK ON TRACK FOR TODAY.
THE UPPER LOW ALONG THE NRN CA COAST THIS MORNING MOVES INLAND TODAY
TO ABOUT NE UT BY MIDDAY WEDNESDAY.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 445 AM MDT TUE APR 7 2015
DOWNSTREAM BLOCKING OVER THE CANADIAN MARITIMES WILL BE RELAXING
OVER THE NEXT 48 HOURS. THIS WILL ALLOW ENERGY THAT HAS BEEN STALLED
UPSTREAM TO MIGRATE THROUGH THE NORTHERN HALF OF THE CONUS THIS
WEEK. THE STORM OF INTEREST TO OUR REGION REMAINS STUCK OFF THE
OREGON COAST WITH NO SIGNIFICANT HEIGHT FALLS SEEN IN HAND ANALYSIS
THIS MORNING. GOES DERIVED IMAGERY ALSO SUGGESTS PACIFIC MOISTURE
TAP IS WEAK WITH THE BULK OF THE MOISTURE WELL TO OUR SOUTH AND
HEADED TO THE PLAINS THROUGH THE WEEK. WATER VAPOR DOES INDICATE A
STRONGER BRANCH OF THE JET ROUNDING THE BASE OF THE LOW IN CENTRAL
CALIFORNIA THIS MORNING WHICH WILL HELP PULL THE SYSTEM ON SHORE
THROUGH THE AFTERNOON...MOVING TO THE WESTERN UTAH BORDER BY
WEDNESDAY. THIS WILL KEEP A TIGHT SOUTHWEST GRADIENT IN PLACE AND
LEAD TO ANOTHER WINDY AND WARM DAY ACROSS THE CWA WHICH IS LIKELY
TO CONTINUE OVERNIGHT AND KEEP MID-SLOPES MIXED AND POSSIBLY SOME
VALLEYS FOR MILD LOW TEMPERATURES.
QG FIELDS SUGGEST THE CORE OF THIS STORM WILL PASS TO OUR NORTH.
HOWEVER DECENT LARGE SCALE ASCENT STILL OCCURS OVER OUR NORTHERN CWA
THANKS TO A CYCLONICALLY CURVED JET TRANSLATING ACROSS WESTERN
COLORADO CONCURRENTLY WITH THE TROUGH PASSAGE TOMORROW AFTERNOON. A
COLD FRONT WILL BE REFLECTED AT THE SURFACE JUST AHEAD OF THE UPPER
TROUGH PASSAGE AND HELP SOME LOW LEVEL CONVERGENCE. HOWEVER STILL
FEEL MOISTURE...OR LACK THERE OF...IS THE MAIN INGREDIENT LACKING
FOR A DECENT PRECIPITATION EVENT. MODEL PWAT OUTPUT REMAINS AOB ONE
QUARTER OF AN INCH THROUGH THIS EVENT AND ENSEMBLE ANOMALIES HAVE
SHOWN THIS DRIER THAN NORMAL TREND FOR THE PAST SEVERAL DAYS. THERE
WILL BE SOME OCTANE IN THE FORM OF CONDITIONAL INSTABILITY WHICH MAY
TEMPORARILY BOOST PRECIPITATION RATES BUT ANTICIPATE THIS WILL BE
VERY LOCALIZED. THE BIGGER IMPACT WILL BE THE COOLER AIR DIVING
IN BEHIND THE FRONT. SIMILAR TO LAST WEEK...TEMPERATURES WILL BE
FALLING QUICKLY THROUGH THE LATE AFTERNOON AND EVENING AND SET THE
STAGE FOR A COLD MID TO LATE WEEK PERIOD.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 445 AM MDT TUE APR 7 2015
H5 TROF AXIS WILL BE PASSING THROUGH THE FORECAST AREA WEDNESDAY
NIGHT WITH STRONG CAA IN PLACE. SNOW LEVELS ARE EXPECTED TO DROP
TO THE HIGHER VALLEY FLOORS OR AROUND THE 6K LEVEL...WITH BEST
MOISTURE AND FORCING GENERALLY ALONG AND NORTH OF INTERSTATE 70.
ACCUMULATING SNOWFALL WILL FAVOR THE EASTERN UINTA MOUNTAINS IN
NORTHEAST UTAH AND THE PARK AND GORE RANGES IN NORTHERN COLORADO.
LATEST NAM12 RUN IS SUPER AGGRESSIVE WITH SNOWFALL AMOUNTS ACROSS
THE EASTERN UINTAS WHERE 30+ INCHES FORECAST. MODEL IS LIKELY
SUFFERING WITH SOME CONVECTIVE FEEDBACK PROBLEMS AND WILL
BASICALLY THROW THAT SOLUTION OUT. REMAINING MODELS MORE
REASONABLE WITH ACCUMULATIONS IN THIS AREA WITH LATE SEASON
ADVISORIES POSSIBLE WITH CONVECTIVELY ENHANCED ACCUMULATIONS UP TO
6 INCHES POSSIBLE FOR THE 24 HOUR PERIOD BEGINNING WEDNESDAY
NIGHT.
SYSTEM CLEARS OUT THURSDAY NIGHT WITH DRY CONDITIONS MOVING BACK
IN. THE EXCEPTION WILL BE ACROSS THE FAR NORTHERN ZONES AS A WEAK
SYSTEM TRACKS ENE ACROSS IDAHO AND NORTHERN WYOMING FRIDAY. TAIL
END OF ENERGY MAY KICK OFF A FEW LIGHT SHOWERS OVER THE HIGHER
TERRAIN ALONG THE WYOMING STATE LINE...OTHERWISE MINIMAL IMPACT
ANTICIPATED. PATTERN FLATTENS OUT A BIT OVER THE WEEKEND AND INTO
EARLY NEXT WEEK WITH ADDITIONAL ENERGY CLIPPING THE NORTHERN
MOUNTAINS LATE SATURDAY AND SUNDAY. ELSEWHERE...DRY CONDITIONS ARE
EXPECTED TO CONTINUE.
TEMPERATURES WILL BE DROPPING QUICKLY WEDNESDAY NIGHT BEHIND THE
FRONT...WITH FREEZING CONDITIONS POSSIBLE IN THE LOWER VALLEYS
WHERE FRUIT TREES AND OTHER TENDER VEGETATION COULD BE THREATENED.
AS A RESULT...WILL BE ISSUING A FREEZE WATCH FOR LATE WEDNESDAY
NIGHT THROUGH EARLY THURSDAY MORNING. SIMILAR TEMPS POSSIBLE
THURSDAY NIGHT...BEFORE TEMPS START MODIFYING OVER THE WEEKEND.
BIG QUESTION WITH THE FREEZE WATCH IS THE AMOUNT OF CLOUD COVER
THAT MAY LINGER OVER THE REGION. THIS WOULD LIMIT THE COLDEST
TEMPS TO JUST A FEW HOURS AROUND SUNRISE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1059 AM MDT TUE APR 7 2015
GUSTY SOUTHWEST SURFACE WINDS AND TURBULENCE ALOFT WILL LIKELY BE
THE MAIN AVIATION HAZARDS THIS AFTERNOON AND EVENING. EXPECT
SOUTHWEST WINDS GUSTING BETWEEN 30-40 KTS AT TIMES UNTIL 03Z AT MANY
VALLEY LOCATIONS INCLUDING THE TAF SITES. THE WIND MAY KICK UP SOME
AREAS OF BLOWING DUST...ALTHOUGH WIDESPREAD RESTRICTIONS TO
VISIBILITY. UPPER LEVEL LOW PRESSURE ALONG THE CA COAST WILL MOVE TO
ABOUT NE UT BY MIDDAY WED. CLOUDS WILL INCREASE AFTER 06Z TONIGHT
WITH BASES LOWERING WED MORNING BUT REMAINING VFR AT THE TAF SITES
THROUGH 18Z. MVFR CONDITIONS IN SCT -SHSN ARE POSSIBLE OVER THE ERN
UINTA MTNS AND THE NW CO MTNS AFTER 12Z WED.
&&
.FIRE WEATHER...
ISSUED AT 445 AM MDT TUE APR 7 2015
...CRITICAL FIRE WEATHER CONDITIONS CONTINUE INTO WEDNESDAY...
STRONG SOUTHWEST GRADIENT WINDS WILL CONTINUE ALOFT AND WILL
EASILY MIX TO THE SURFACE AS TEMPERATURES REMAIN ABOVE NORMAL AND
INSTABILITY STRONG. THE AIR MASS REMAINS VERY DRY WITH AFTERNOON
HUMIDITY VALUES RANGING FROM 5 TO 15 PERCENT AND POOR RECOVERY
EXPECTED AGAIN TONIGHT. SOME MOISTURE WILL SPREAD INTO THE AREA
ON WEDNESDAY BUT COOLER AIR ARRIVING WILL BE THE MAIN FACTOR FOR
HELPING INCREASE HUMIDITY. VIRGA IS LIKELY TO PROCEED ANY
PRECIPITATION ON WEDNESDAY AND HELP CREATE LOCALLY STRONG WIND
GUSTS THROUGH THE AFTERNOON. COLORADO ZONE 207 HAS THE POTENTIAL
TO REACH CRITICAL FIRE WEATHER CONDITIONS FOR LOW HUMIDITY AND
GUSTY WINDS AHEAD OF THE FRONT WEDNESDAY AFTERNOON. COOLER AND
WETTER CONDITIONS ARE EXPECTED WEDNESDAY EVENING THROUGH THURSDAY
NIGHT FAVORING THE NORTH. THE NEXT CHANCE OF SHOWERS ARRIVES SATURDAY
NIGHT INTO MONDAY.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...FREEZE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY MORNING
FOR COZ006-011-020.
RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR
COZ200-202-203-205-207-290-292.
UT...FREEZE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY MORNING
FOR UTZ022-027.
&&
$$
UPDATE...JAD
SHORT TERM...15
LONG TERM...JDC
AVIATION...JAD
FIRE WEATHER...TGJT
AREA FORECAST DISCUSSION
NWS MIAMI FL
138 PM EDT TUE APR 7 2015
.AVIATION...
HIGH PRESSURE CONTINUES TO KEEP THE WEATHER QUIET ACROSS SOUTH
FLORIDA. ALTHOUGH, THERE MAY BE SOME ISOLATED SHOWERS OVER THE
WESTERN HALF, NEAR KAPF. THERE IS ALSO A VERY SLIGHT POSSIBILITY
THAT A FEW OF ANY SHOWERS THAT ARE ABLE TO DEVELOP, MAY TURN INTO
A THUNDERSTORM. HOWEVER, THE UNCERTAINTY IS LOW ENOUGH THAT NO
MENTION OF EVEN THE SHOWERS ARE IN THE TAFS AT THIS TIME. SKIES
SHOULD BECOME MOSTLY CLEAR TO CLEAR TONIGHT. TOMORROW WILL SEE
ANOTHER ROUND OF AFTERNOON CLOUDS DEVELOP.
&&
.PREV DISCUSSION... /ISSUED 1118 AM EDT TUE APR 7 2015/
UPDATE...
JUST MADE A QUICK CHANGE TO ADD A SLIGHT CHANCE OF THUNDER OVER
THE INTERIOR AND WEST COAST FOR LATE THIS AFTERNOON AND EARLY
EVENING. THIS BASED ON CLOSER EXAMINATION TO THE MORNING SOUNDING
AND DECIDED THE AIRMASS IS SHOWING ENOUGH INSTABILITY THAT CANNOT
RULE OUT A POSSIBLE LIGHTNING STRIKE.
PREV DISCUSSION... /ISSUED 902 AM EDT TUE APR 7 2015/
UPDATE...
CURRENT ANALYSIS SHOWS MID/UPPER LEVEL RIDGE OVER THE EASTERN GULF
OF MEXICO AND SURFACE RIDGE FROM THE SOUTHEAST STATES INTO THE
ATLANTIC. DO NOT PLAN TO MAKE ANY MAJOR CHANGES WITH THE MORNING
UPDATES. THE 12Z MFL SOUNDING SHOWS MARGINAL INSTABILITY BUT STILL
QUITE DRY WITH PWAT AT LESS THAN 1.5" WHICH IS SLIGHTLY ABOVE THE
EARLY APRIL AVERAGE OF AROUND 1.2". SO THIS COMBINED WITH PLENTY
OF DIURNAL HEATING ALONG WITH A WELL ESTABLISHED LOW LEVEL
SOUTHEAST FLOW WILL RESULT IN A FEW LATE AFTERNOON/EARLY EVENING
SHOWERS OVER THE INTERIOR AND WEST COAST. THE HRRR SHOWS THIS
ACTIVITY BEGINNING AROUND 19Z AND PERSISTING UNTIL 01-02Z THIS
EVENING. THIS SEEMS REASONABLE BASED ON THE ABOVE DISCUSSION.
KOB
PREV DISCUSSION... /ISSUED 323 AM EDT TUE APR 7 2015/
DISCUSSION...
ABOVE NORMAL HIGH AND LOW TEMPERATURES ARE EXPECTED EACH DAY
THROUGH THE FORECAST PERIOD...WITH HIGHS IN THE 80S TO LOW 90S AND
LOWS IN THE MID 60S TO MID 70S. SHOWERS ARE POSSIBLE TODAY AND
WEDNESDAY FOR THE GULF COAST...WITH DRY CONDITIONS ON THURSDAY.
SEA BREEZE SHOWERS AND THUNDERSTORMS RETURN TO THE REGION FRIDAY
THROUGH THE WEEKEND...ESPECIALLY INTERIOR AND WEST.
SHOWERS OVER THE GULF COAST AND ATLANTIC WATERS HAVE
DIMINISHED...BUT A FEW SPRINKLES ARE POSSIBLE ALONG THE EAST COAST
OVER THE NEXT COUPLE HOURS. EASTERLY WINDS TODAY WILL BE IN THE
10-15 MPH RANGE AS SURFACE HIGH PRESSURE SETTLES OVER THE WESTERN
ATLANTIC. A WEAK SHORTWAVE WILL SLIDE SOUTHEAST DOWN THE
PENINSULA THIS AFTERNOON AND INTO THE REGION THIS EVENING. THIS
MAY ENHANCE SHOWERS ALONG THE SEA BREEZE THIS AFTERNOON...BUT THE
BEST LIFT WILL BE ACROSS CENTRAL FLORIDA SO WILL LEAVE MENTION OF
THUNDERSTORMS OUT TODAY. LOW LEVEL MOISTURE WILL INCREASE IN THE
EVENING FOR THE EAST COAST...AND WITH THE SHORTWAVE MOVING INTO
THE REGION...A FEW SHOWERS ARE POSSIBLE. SOME LOWER CEILINGS ARE
ALSO POSSIBLE FOR THE EAST COAST.
A SHORTWAVE TROUGH WILL MOVE INTO THE INTERMOUNTAIN WEST ON
WEDNESDAY...AND THE MID/UPPER RIDGE OVER THE GULF WILL AMPLIFY
ACROSS THE EASTERN SEABOARD. A FEW SHOWERS ARE STILL POSSIBLE
ALONG THE GULF COAST SEA BREEZE...BUT OVERALL ACTIVITY WILL BE
LIMITED.
MID/UPPER LEVEL RIDGING WILL THEN TAKE OVER THE WEATHER ON
THURSDAY. THE SHORTWAVE TROUGH WILL LIFT NORTHEASTWARD INTO THE
GREAT LAKES ON FRIDAY...AND THE MID/UPPER LEVEL RIDGE WILL SHIFT
INTO THE WESTERN ATLANTIC. SURFACE HIGH PRESSURE WILL PUSH
EASTWARD...AND SOUTHEAST LOW LEVEL FLOW WILL ALLOW DEEPER MOISTURE
TO PUSH INTO THE REGION. SO SCATTERED SHOWERS AND STORMS ARE
POSSIBLE ALONG THE SEA BREEZE CONVERGENCE ACROSS THE INTERIOR AND
GULF COAST. SIMILAR CONDITIONS ARE EXPECTED ON SATURDAY...WITH THE
BEST CHANCE OF SHOWERS AND STORMS ACROSS THE INTERIOR AND GULF
COAST.
AN UPPER TROUGH WILL THEN DIG ACROSS THE MIDDLE OF THE COUNTRY
SUNDAY INTO SUNDAY NIGHT...WITH THE MID/UPPER RIDGE AMPLIFYING
ACROSS THE REGION ONCE AGAIN INTO EARLY NEXT WEEK. SEA BREEZE
SHOWERS AND STORMS ARE POSSIBLE ON SUNDAY...WITH DRIER CONDITIONS
THEN RETURNING TO THE REGION.
MARINE...
AN EAST TO SOUTHEAST WIND WILL CONTINUE THROUGH THE PERIOD WITH
SEAS OF 2-4 FEET OVER THE ATLANTIC WATERS AND 1-2 FEET IN THE GULF
WATERS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 72 85 73 85 / 10 10 0 10
FORT LAUDERDALE 73 83 73 84 / 10 10 0 10
MIAMI 72 85 73 86 / 10 10 0 10
NAPLES 69 89 68 89 / 20 20 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...30/KOB
LONG TERM....84/AK
AVIATION...13/SI
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
301 PM CDT TUE APR 7 2015
.UPDATE...
1129 AM CDT
HAVE UPDATED GRIDS/TEXT PRODUCTS ALREADY TO LOWER TEMPERATURES
TODAY...ESPECIALLY NEAR THE LAKE WHERE STIFF WIND OFF THE LAKE
SHOULD MAKE IT HARD FOR TEMPS TO EVEN REACH 40 THIS AFTERNOON.
WEBCAMS ALONG THE LAKE AND LAURIE CHILDREN`S HOSP HELIPORT AWOS
INDICATE THAT DENSE MARINE FOG IS MAKING IT SLIGHTLY ONSHORE.
CERTAINLY POSSIBLE THAT FOG COULD GROW DENSER ALONG THE LAKE LATER
TODAY OR TONIGHT AND POTENTIALLY REQUIRE A HEADLINE. HAVE BACKED
OFF ON POPS SIGNIFICANTLY TODAY ONE MCV PASSES WELL TO OUR SOUTH
AND WE ARE LEFT WAITING FOR THE NEXT UPSTREAM IMPULSE TO KICK OFF
CONVECTION WHICH LOOKS TO BE TONIGHT...OR POSSIBLE VERY LATE THIS
AFTERNOON WESTERN CWA.
IZZI
&&
.SHORT TERM...
408 AM CDT
TODAY THROUGH THURSDAY NIGHT...
THE MAIN FOCUS IN THE NEAR TERM REMAINS ON IDENTIFYING THE BEST
TIMING FOR ROUNDS OF SHOWERS AND THUNDERSTORMS AS INDIVIDUAL SHORT
WAVES PROPAGATE ALONG WEST-EAST BAROCLINC ZONE ASSOCIATED WITH A
NEARLY STATIONARY SURFACE FRONT ACROSS CENTRAL ILLINOIS AND
INDIANA. IN ADDITION...SUBSTANTIAL CONCERN IS BREWING FOR THE
POTENTIAL OF ORGANIZED SEVERE WEATHER ON THURSDAY...WITH ENERGETIC
UPPER TROUGH AND DEEP SURFACE LOW EXPECTED TO MOVE INTO THE AREA.
THIS MORNING...THE NEARLY STATIONARY SURFACE FRONT HAS DRIFTED A
BIT TO THE SOUTH IN THE WAKE OF A MINOR-AMPLITUDE MID-LEVEL SHORT
WAVE AND WEAK SURFACE WAVE ALONG THE FRONT WHICH WAS MOVING INTO
INDIANA. A CLUSTER OF SHOWERS AND A FEW THUNDERSTORMS HAVE ALSO
MOVED OFF TO THE EAST EARLY THIS MORNING WITH THE AXIS OF BETTER
LOW LEVEL MOISTURE TRANSPORT AND THE VEERING OF A MODEST 30 KT LOW
LEVEL JET ASSOCIATED WITH THE PASSING SHORT WAVE. WHILE SOME LIGHT
DRIZZLE OR SPOTTY LIGHT SHOWERS WILL REMAIN POSSIBLE WITH WEAK BUT
PERSISTENT WARM/MOIST ADVECTION WITHING THE FRONTAL ZONE...IT
APPEARS THERE WILL BE A LULL IN MORE ORGANIZED PRECIPITATION UNTIL
ANOTHER SHORT WAVE ARRIVES. LOOKING UPSTREAM IN WATER VAPOR
IMAGERY THIS MORNING ONE SUCH WAVE WAS EVIDENT OVER EASTERN
KANSAS...WITH ELEVATED CONVECTION NOTED JUST EAST OF KANSAS CITY.
YET ANOTHER IDENTIFIABLE WAVE WAS CROSSING THE CENTRAL ROCKIES.
PRECIP POTENTIAL THUS LOOKS TO INCREASE AGAIN FROM THE
WEST/SOUTHWEST THIS AFTERNOON INTO TONIGHT AS THESE WAVES
APPROACH. MODELS HAVE CONSISTENTLY DEPICTED THE DEEPER COLORADO
SHORT WAVE TRACKING TOWARD THE REGION TONIGHT INTO EARLY
WEDNESDAY...ENHANCING WARM/MOIST ADVECTION INTO THE FORECAST AREA
TONIGHT. STRONGER MOISTURE TRANSPORT LOOKS TO FOCUS INTO THE AREA
BY EARLY EVENING WITH GOOD SUPPORT FOR SHOWERS AND
THUNDERSTORMS...NOTABLY STEEP MID-LEVEL LAPSE RATES IN EXCESS OF
7.5 C/KM AND A POSITION BENEATH RIGHT ENTRANCE DIVERGENCE REGION
OF UPPER JET STREAK NORTHEAST OF THE LAKES. HAVE CARRIED LIKELY
POPS AND MENTION OF THUNDER CWA-WIDE TONIGHT...BEFORE PRECIP
COVERAGE IS EXPECTED TO AGAIN DECREASE AFTER SUNRISE WEDNESDAY
MORNING AS THE WAVE TRACKS TO THE EAST AND LOW LEVEL JET
VEERS/WEAKENS.
ATTENTION THEN TURNS TO THE UPPER TROUGH WHICH HAS BEEN JUST OFF
OF THE WEST COAST...AND IS PROGGED TO MOVE INLAND ACROSS THE
INTERMOUNTAIN WEST AND THE ROCKIES THROUGH WEDNESDAY. GUIDANCE HAS
REMAINED SIMILAR IN WRAPPING JET ENERGY AROUND THE BASE OF THIS
DEEP UPPER LOW AND EJECTING SHORT WAVE ACROSS THE MID-MISSISSIPPI
VALLEY LATE WEDNESDAY AND WEDNESDAY NIGHT...WITH THE MAIN UPPER
TROUGH THEN LIFTING NORTHEAST AND BECOMING A SOMEWHAT
COMPACT/NEGATIVE TILT SYSTEM AS IT APPROACHES OUR AREA ON
THURSDAY. THIS SETS THE STAGE FOR STRONG THERMAL/MOISTURE
ADVECTION DEVELOPING ACROSS THE MIDWEST LATE WEDNESDAY AND
WEDNESDAY NIGHT...AND THE SURFACE FRONT LIFTING NORTH AS A WARM
FRONT ACROSS THE AREA THROUGH THURSDAY AS THE DEEP SURFACE LOW
WITH THE MAIN UPPER TROUGH MOVES INTO THE UPPER MIDWEST. THIS
LOOKS TO PRODUCE A FAIRLY WIDESPREAD AREA OF CONVECTION WHICH WILL
IMPACT THE CWA WEDNESDAY NIGHT INTO EARLY THURSDAY.
AS THE WARM FRONT LIFTS NORTH INTO/ACROSS THE CWA THURSDAY
AFTERNOON...THE MOISTURE RICH WARM SECTOR HAS THE POTENTIAL TO
BECOME STRONGLY UNSTABLE. FORECAST SOUNDINGS FROM THE GFS AND NAM
BOTH DEPICT MLCAPES IN THE 1500-2500 J/KG RANGE IN THE WARM SECTOR
ACROSS OUR AREA BY THURSDAY AFTERNOON...COINCIDENT WITH 40-50 KT
0-6 KM BULK SHEAR AND STRONG ASCENT AHEAD OF APPROACHING DEEP
UPPER TROUGH. MANY MODEL RUNS TAKE THE SYSTEM SURFACE LOW ACROSS
NORTHEAST IA/SOUTHWEST WI BY THURSDAY EVENING..WITH A COLD FRONT
PUSHING ACROSS THE MISSISSIPPI RIVER AND ACROSS NORTHERN IL/IN
THURSDAY EVENING. THIS LOOKS TO PRESENT A SUBSTANTIAL SEVERE
WEATHER THREAT ESPECIALLY IN THE THURSDAY AFTERNOON/EARLY EVENING
PERIOD...WITH MORE THAN SUFFICIENT SHEAR/INSTABILITY FOR SUPERCELL
STORMS WHICH MAY THEN EVOLVE INTO A SEVERE LINEAR MCS. DETAILS OF
MORNING CONVECTIVE DEBRIS AND CLOUDINESS AND POSITION OF THE
EFFECTIVE SURFACE WARM FRONTAL BOUNDARY WILL ALL ULTIMATELY AFFECT
HOW AFTERNOON STORMS EVOLVE. SPC HAS MAINTAINED A 30 PERCENT
ENHANCED SEVERE RISK AREA OVER OUR ENTIRE CWA FOR THIS PERIOD.
SEVERE THREAT AS WELL AS GENERAL SHOWER/THUNDERSTORM THREAT SHOULD
DIMINISH QUICKLY BEHIND THE COLD FRONT THURSDAY NIGHT.
TEMPS WILL CONTINUE TO SHOW BIG NORTH-SOUTH RANGE WITH EAST-
NORTHEAST FLOW OFF COOL LAKE KEEPING NORTHERN COUNTIES AND
ESPECIALLY LAKE SHORE AREAS CHILLY THROUGH WEDNESDAY NIGHT.
FARTHER SOUTH...CLOSER TO THE SURFACE FRONT TEMPS WILL LIKELY BE
ABLE TO REACH THE MID-UPPER 60S ESPECIALLY IF A LITTLE SUN BREAKS
THROUGH. ON THURSDAY...70S ARE LIKELY ALONG/SOUTH OF THE NORTHWARD
ADVANCING WARM FRONT.
RATZER
&&
.LONG TERM...
422 AM CDT
FRIDAY THROUGH MONDAY...
WITH THE COLD FRONT EAST OF THE FORECAST AREA BY EARLY
FRIDAY...AND THE UPPER TROUGH AND SURFACE LOW PASSING NORTH OF THE
IL/WI BORDER FOR THE MOST PART...DRIER AIR MOVES IN FOR FRIDAY AND
SATURDAY AS SURFACE HIGH PRESSURE MOVES INTO THE REGION. MEDIUM
RANGE GUIDANCE SHOWING SOME DIFFERENCE IN DETAILS WITH PATTERN
OVER THE WEEKEND AND INTO EARLY NEXT WEEK BUT GENERALLY DEVELOP
UPPER RIDGE ACROSS THE AREA SATURDAY NIGHT AND SUNDAY...DOWNSTREAM
OF AN AMPLIFIED UPPER TROUGH OVER THE WESTERN CONUS. THIS SETS UP
A RETURN OF SOUTH FLOW AND WARM/MOIST ADVECTION LATER SUNDAY AND
MONDAY...WITH THE POTENTIAL FOR SHOWERS AND STORMS TO RETURN AS
THE UPPER TROUGH APPROACHES. AFTER A SLIGHT COOL-DOWN FRIDAY INTO
SATURDAY (THOUGH NEAR NORMAL AND WARMER THAN OUR CURRENT CHILLY
TEMPS)...WARMER WEATHER RETURNS SUNDAY-MONDAY WITH HIGHS IN THE
MID-UPPER 60S.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* PERSISTENT IFR CIGS/VSBYS THIS AFTERNOON WITH LIFR POSSIBLE.
* NORTHEAST WINDS GUSTING AT TIMES OVER 20 KTS.
* TSRA CHANCES OVERNIGHT.
* CONTINUED IFR TOMORROW.
LENNING
//DISCUSSION...UPDATED 18Z...
CONDITIONS CONTINUE TO DETERIORATE GRADUALLY THIS AFTERNOON
RAISING THE QUESTION OF HOW LOW CIGS AND VSBYS WILL DROP. CIGS
RANGED FROM 300-600FT IN THE CHI METRO AREA AS OF THE 18Z TAF
TIME WITH THE LOWEST VALUES JUST SOUTH OF THE MDW TERMINAL.
MEANWHILE TO THE NORTH TOWARD MKX CONDITIONS WERE STAYING IN THE
MVFR TO VFR RANGE. BETTER SFC AND LOW LEVEL MOISTURE OVER NE IL
WOULD APPEAR TO BE SUPPORTING THE LOWER CONDITIONS IN THIS AREA.
MODELS SUGGEST PERSISTENCE OR EVEN EXPANSION OF THIS MOISTURE
THROUGH THE DAY INTO THE EVENING HOURS. A BREAK MAY COME WITH THE
DEVELOPMENT OF SHOWERS AND POSSIBLE THUNDERSTORMS TOWARD LATE
EVENING THOUGH THIS WOULD BE AFTER THE PEAK TRAFFIC PERIOD.
TOMORROW SHOWS LITTLE CHANGE AFTER PRECIPITATION MOVES OUT DURING
THE PREDAWN HOURS. IN FACT...WITH THE PERSISTENT AIRMASS AND
INCREASED SURFACE MOISTURE INTRODUCED BY OVERNIGHT
RAINFALL...THE POTENTIAL EXISTS FOR LOWER CONDITIONS
TOMORROW...AT LEAST THROUGH THE MORNING.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* LOW TO MEDIUM CONFIDENCE IN CIG/VSBY TRENDS...STILL UNSURE OF
WHETHER THEY GO TO LIFR THIS AFTERNOON AND EVENING.
* MEDIUM TO HIGH CONFIDENCE IN WINDS REMAINING MAINLY NORTHEAST.
* MEDIUM CONFIDENCE IN SHRA AND TSRA TIMING TONIGHT.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT...SHRA/TSRA. IFR. EAST/SOUTHEAST WINDS.
* THURSDAY...STRONG TSRA. MVFR. STRONG/GUSTY SOUTH/SOUTHWEST
WINDS.
* FRIDAY...DRY/VFR. STRONG/GUSTY WEST WINDS.
* SATURDAY...DRY/VFR. SOUTH WINDS. LAKE BREEZE POSSIBLE.
* SUNDAY...DRY/VFR. SOUTHEAST WINDS.
* MONDAY...CHANCE OF SHRA/TSRA. MVFR POSSIBLE. SOUTH WINDS.
&&
.MARINE...
348 AM...A FRONTAL BOUNDARY WILL REMAIN GENERALLY STATIONARY
THROUGH WEDNESDAY JUST SOUTH OF LAKE MICHIGAN...AS STRONG HIGH
PRESSURE MOVES ACROSS ONTARIO TODAY AND INTO QUEBEC TONIGHT. THIS
WILL TIGHTEN THE GRADIENT LATER TODAY INTO TONIGHT WITH A PERIOD
OF 30KTS EXPECTED. LOW PRESSURE WILL DEVELOP OVER THE CENTRAL
PLAINS WEDNESDAY NIGHT AND MOVE NORTHEAST TOWARD NORTHERN LAKE
MICHIGAN BY FRIDAY MORNING. THE EXACT TRACK OF THIS LOW REMAINS
SOMEWHAT UNCERTAIN...BUT THESE TRENDS WOULD SUPPORT THE FRONTAL
BOUNDARY MOVING NORTH AS A WARM FRONT WEDNESDAY NIGHT INTO
THURSDAY. THUS THERE IT THE POTENTIAL FOR LARGE CHANGES TO WIND
DIRECTIONS OVER PARTS OF THE LAKE FROM WEDNESDAY NIGHT INTO
THURSDAY NIGHT. EVENTUALLY WINDS WILL SHIFT WESTERLY LATE THURSDAY
NIGHT INTO FRIDAY MORNING...THEN BEGIN TO DIMINISH FRIDAY NIGHT AS
HIGH PRESSURE MOVES ACROSS THE LAKE ON SATURDAY. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 10 PM
WEDNESDAY.
&&
$$
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1255 PM CDT Tue Apr 7 2015
.UPDATE...
ISSUED AT 1040 AM CDT TUE APR 7 2015
Will update the forecast around 11 am when dense fog advisory over
central IL expires. Some patchy fog may linger into midday over areas
north of I-70 but most of the dense fog over central IL should
lift late this morning. A frontal boundary has sagged southward
into central IL near I-72 late this morning and HRRR models keeps
this boundary near I-72 into early evening. 1007 mb surface low
pressure over ne KS will track into nw MO early this evening and
tug front slowly back north during tonight. Have cooled highs
north of this boundary with upper 50s and lower 60s for highs from
Galesburg, Peoria and Bloomington north where low clouds persist.
Showers south of I-72 with thunderstorms from Litchfied sw and
some strong to severe with heavy rains from St Louis south. Severe
storms should stay along and south of I-64 today though a few
thunderstorms could affect areas from I-72 south this afternoon
along and south of the boundary. Milder highs in low to mid 70s in
sw CWA from Springfield to Terre Haute sw where some peaks of
sunshine to appear during the afternoon.
&&
.SHORT TERM...(Today)
ISSUED AT 335 AM CDT TUE APR 7 2015
A few showers and isolated thunderstorms will continue to move
across southeast Illinois early this morning. HiRes short term
models develop another area of showers and isolated thunderstorms
over northern MO and then bring them into central IL late morning
and into the afternoon. The warm front has setup and is sitting
right through central IL, north of a Quincy to Springfield to
Mattoon line, which puts half of the cwa south of the front, and
the I-74 area, including Lincoln, north of the front. So, area of
convection that does develop should follow along and just north of
the front when it arrives later this morning. So, have likely pops
in the southeast for this morning, and then slightly higher pops
in the afternoon for the west central. With front right across CWA
high temp spread with be around 15 degrees across the CWA today.
Cloud cover will also be persistent today, with some light fog
this morning. With pcpn being mainly scattered, qpf values will
not be that significant.
&&
.LONG TERM...(Tonight through Monday)
ISSUED AT 335 AM CDT TUE APR 7 2015
The warm front should become a little more active this evening and
shift north, as the first in a series of low pressure areas moves
along the frontal zone. So, higher pcpn chances will be in the
north for tonight with chance pops remaining for the rest of the
area, which will be in the warm sector. Lowest pops will be in the
south. As this first low moves east, it will drag the cold front
south through the cwa, so pops for Wed morning will be higher to
the south and only a slight chance in the north. However, the next
wave/low press area will lift out Wed afternoon and return chance
pops for the whole area. This one will lift northeast through the
area and bring much higher chances of pcpn to the CWA for late Wed
afternoon through Wed night. Per SPC day 2 outlook, there is a
slight risk of severe weather nosing into west central IL for late
Wed afternoon and into Wed night. Highest pops will be west of
I-55. Probably will be a little break Wed night after midnight,
but will not put that in just yet.
Then on Thursday, the main sfc system will lift out of the plains
with the associated mid level wave. Though there may be pcpn
ongoing Thur morning in the east, by afternoon most of the area
should be pcpn free and the atmosphere should be able to recover
before the next round of pcpn. Forecasted CAPE values will be 2000
to 2500 across a good portion of IL in the warm sector ahead of
the front. A strong upper level jet will also be pushing into the
area at the same time, so wind dynamics and shear will be
sufficient that storms will likely rotate. There is still some
uncertainty as to how this will play out Thur given the Wed night
and early morning convection, but if airmass recovers, it looks
like a line of convection will develop just west of the state late
afternoon and then move east across the state Thur evening. All
forms of severe weather look to be possible late afternoon through
the evening hours. Something to consider is that storms may be
moving at about 40-45 mph. By midnight, most of the storms should
be east of the state, but will hang on to some chance pops.
Past this system, dry conditions are expected for Fri through Sat
night. Then another system moves toward the area for Sunday
through Monday with more showers and storms.
Expecting very warm temps for Thur, but then temps will cool some
Fri and Sat, but warm back a tad for Sun and Mon.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 1255 PM CDT TUE APR 7 2015
Dense fog lingering at BMI...CMI and DEC airports will gradually
lift into mid afternoon with MVFR to possibly vfr vsbys. Vsbys at
PIA and SPI have lifted to 1-2 miles and to lift to MVFR and VFR
next few hours. Very low ceilings of 100-300 ft to lift to
700-1500 feet during mid/late afternoon across central IL. I-72 is
on northern edge of showers and isolated thunderstorms and will
carry vcsh at SPI and DEC into mid afternoon with VCTS at CMI.
Scattered showers/thunderstorms possible by overnight into mid
morning Wed as frontal boundary just south of I-72 lifts slowly
back north as 1007 mb surface low pressure over ne KS moves into
central IL by 12Z/Wed. ENE winds around 10 kts to veer SSE during
tonight and SW Wed morning.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...07
SHORT TERM...Auten
LONG TERM...Auten
AVIATION...07
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1105 AM CDT TUE APR 7 2015
.SHORT TERM...
408 AM CDT
TODAY THROUGH THURSDAY NIGHT...
THE MAIN FOCUS IN THE NEAR TERM REMAINS ON IDENTIFYING THE BEST
TIMING FOR ROUNDS OF SHOWERS AND THUNDERSTORMS AS INDIVIDUAL SHORT
WAVES PROPAGATE ALONG WEST-EAST BAROCLINC ZONE ASSOCIATED WITH A
NEARLY STATIONARY SURFACE FRONT ACROSS CENTRAL ILLINOIS AND
INDIANA. IN ADDITION...SUBSTANTIAL CONCERN IS BREWING FOR THE
POTENTIAL OF ORGANIZED SEVERE WEATHER ON THURSDAY...WITH ENERGETIC
UPPER TROUGH AND DEEP SURFACE LOW EXPECTED TO MOVE INTO THE AREA.
THIS MORNING...THE NEARLY STATIONARY SURFACE FRONT HAS DRIFTED A
BIT TO THE SOUTH IN THE WAKE OF A MINOR-AMPLITUDE MID-LEVEL SHORT
WAVE AND WEAK SURFACE WAVE ALONG THE FRONT WHICH WAS MOVING INTO
INDIANA. A CLUSTER OF SHOWERS AND A FEW THUNDERSTORMS HAVE ALSO
MOVED OFF TO THE EAST EARLY THIS MORNING WITH THE AXIS OF BETTER
LOW LEVEL MOISTURE TRANSPORT AND THE VEERING OF A MODEST 30 KT LOW
LEVEL JET ASSOCIATED WITH THE PASSING SHORT WAVE. WHILE SOME LIGHT
DRIZZLE OR SPOTTY LIGHT SHOWERS WILL REMAIN POSSIBLE WITH WEAK BUT
PERSISTENT WARM/MOIST ADVECTION WITHING THE FRONTAL ZONE...IT
APPEARS THERE WILL BE A LULL IN MORE ORGANIZED PRECIPITATION UNTIL
ANOTHER SHORT WAVE ARRIVES. LOOKING UPSTREAM IN WATER VAPOR
IMAGERY THIS MORNING ONE SUCH WAVE WAS EVIDENT OVER EASTERN
KANSAS...WITH ELEVATED CONVECTION NOTED JUST EAST OF KANSAS CITY.
YET ANOTHER IDENTIFIABLE WAVE WAS CROSSING THE CENTRAL ROCKIES.
PRECIP POTENTIAL THUS LOOKS TO INCREASE AGAIN FROM THE
WEST/SOUTHWEST THIS AFTERNOON INTO TONIGHT AS THESE WAVES
APPROACH. MODELS HAVE CONSISTENTLY DEPICTED THE DEEPER COLORADO
SHORT WAVE TRACKING TOWARD THE REGION TONIGHT INTO EARLY
WEDNESDAY...ENHANCING WARM/MOIST ADVECTION INTO THE FORECAST AREA
TONIGHT. STRONGER MOISTURE TRANSPORT LOOKS TO FOCUS INTO THE AREA
BY EARLY EVENING WITH GOOD SUPPORT FOR SHOWERS AND
THUNDERSTORMS...NOTABLY STEEP MID-LEVEL LAPSE RATES IN EXCESS OF
7.5 C/KM AND A POSITION BENEATH RIGHT ENTRANCE DIVERGENCE REGION
OF UPPER JET STREAK NORTHEAST OF THE LAKES. HAVE CARRIED LIKELY
POPS AND MENTION OF THUNDER CWA-WIDE TONIGHT...BEFORE PRECIP
COVERAGE IS EXPECTED TO AGAIN DECREASE AFTER SUNRISE WEDNESDAY
MORNING AS THE WAVE TRACKS TO THE EAST AND LOW LEVEL JET
VEERS/WEAKENS.
ATTENTION THEN TURNS TO THE UPPER TROUGH WHICH HAS BEEN JUST OFF
OF THE WEST COAST...AND IS PROGGED TO MOVE INLAND ACROSS THE
INTERMOUNTAIN WEST AND THE ROCKIES THROUGH WEDNESDAY. GUIDANCE HAS
REMAINED SIMILAR IN WRAPPING JET ENERGY AROUND THE BASE OF THIS
DEEP UPPER LOW AND EJECTING SHORT WAVE ACROSS THE MID-MISSISSIPPI
VALLEY LATE WEDNESDAY AND WEDNESDAY NIGHT...WITH THE MAIN UPPER
TROUGH THEN LIFTING NORTHEAST AND BECOMING A SOMEWHAT
COMPACT/NEGATIVE TILT SYSTEM AS IT APPROACHES OUR AREA ON
THURSDAY. THIS SETS THE STAGE FOR STRONG THERMAL/MOISTURE
ADVECTION DEVELOPING ACROSS THE MIDWEST LATE WEDNESDAY AND
WEDNESDAY NIGHT...AND THE SURFACE FRONT LIFTING NORTH AS A WARM
FRONT ACROSS THE AREA THROUGH THURSDAY AS THE DEEP SURFACE LOW
WITH THE MAIN UPPER TROUGH MOVES INTO THE UPPER MIDWEST. THIS
LOOKS TO PRODUCE A FAIRLY WIDESPREAD AREA OF CONVECTION WHICH WILL
IMPACT THE CWA WEDNESDAY NIGHT INTO EARLY THURSDAY.
AS THE WARM FRONT LIFTS NORTH INTO/ACROSS THE CWA THURSDAY
AFTERNOON...THE MOISTURE RICH WARM SECTOR HAS THE POTENTIAL TO
BECOME STRONGLY UNSTABLE. FORECAST SOUNDINGS FROM THE GFS AND NAM
BOTH DEPICT MLCAPES IN THE 1500-2500 J/KG RANGE IN THE WARM SECTOR
ACROSS OUR AREA BY THURSDAY AFTERNOON...COINCIDENT WITH 40-50 KT
0-6 KM BULK SHEAR AND STRONG ASCENT AHEAD OF APPROACHING DEEP
UPPER TROUGH. MANY MODEL RUNS TAKE THE SYSTEM SURFACE LOW ACROSS
NORTHEAST IA/SOUTHWEST WI BY THURSDAY EVENING..WITH A COLD FRONT
PUSHING ACROSS THE MISSISSIPPI RIVER AND ACROSS NORTHERN IL/IN
THURSDAY EVENING. THIS LOOKS TO PRESENT A SUBSTANTIAL SEVERE
WEATHER THREAT ESPECIALLY IN THE THURSDAY AFTERNOON/EARLY EVENING
PERIOD...WITH MORE THAN SUFFICIENT SHEAR/INSTABILITY FOR SUPERCELL
STORMS WHICH MAY THEN EVOLVE INTO A SEVERE LINEAR MCS. DETAILS OF
MORNING CONVECTIVE DEBRIS AND CLOUDINESS AND POSITION OF THE
EFFECTIVE SURFACE WARM FRONTAL BOUNDARY WILL ALL ULTIMATELY AFFECT
HOW AFTERNOON STORMS EVOLVE. SPC HAS MAINTAINED A 30 PERCENT
ENHANCED SEVERE RISK AREA OVER OUR ENTIRE CWA FOR THIS PERIOD.
SEVERE THREAT AS WELL AS GENERAL SHOWER/THUNDERSTORM THREAT SHOULD
DIMINISH QUICKLY BEHIND THE COLD FRONT THURSDAY NIGHT.
TEMPS WILL CONTINUE TO SHOW BIG NORTH-SOUTH RANGE WITH EAST-
NORTHEAST FLOW OFF COOL LAKE KEEPING NORTHERN COUNTIES AND
ESPECIALLY LAKE SHORE AREAS CHILLY THROUGH WEDNESDAY NIGHT.
FARTHER SOUTH...CLOSER TO THE SURFACE FRONT TEMPS WILL LIKELY BE
ABLE TO REACH THE MID-UPPER 60S ESPECIALLY IF A LITTLE SUN BREAKS
THROUGH. ON THURSDAY...70S ARE LIKELY ALONG/SOUTH OF THE NORTHWARD
ADVANCING WARM FRONT.
RATZER
&&
.LONG TERM...
422 AM CDT
FRIDAY THROUGH MONDAY...
WITH THE COLD FRONT EAST OF THE FORECAST AREA BY EARLY
FRIDAY...AND THE UPPER TROUGH AND SURFACE LOW PASSING NORTH OF THE
IL/WI BORDER FOR THE MOST PART...DRIER AIR MOVES IN FOR FRIDAY AND
SATURDAY AS SURFACE HIGH PRESSURE MOVES INTO THE REGION. MEDIUM
RANGE GUIDANCE SHOWING SOME DIFFERENCE IN DETAILS WITH PATTERN
OVER THE WEEKEND AND INTO EARLY NEXT WEEK BUT GENERALLY DEVELOP
UPPER RIDGE ACROSS THE AREA SATURDAY NIGHT AND SUNDAY...DOWNSTREAM
OF AN AMPLIFIED UPPER TROUGH OVER THE WESTERN CONUS. THIS SETS UP
A RETURN OF SOUTH FLOW AND WARM/MOIST ADVECTION LATER SUNDAY AND
MONDAY...WITH THE POTENTIAL FOR SHOWERS AND STORMS TO RETURN AS
THE UPPER TROUGH APPROACHES. AFTER A SLIGHT COOL-DOWN FRIDAY INTO
SATURDAY (THOUGH NEAR NORMAL AND WARMER THAN OUR CURRENT CHILLY
TEMPS)...WARMER WEATHER RETURNS SUNDAY-MONDAY WITH HIGHS IN THE
MID-UPPER 60S.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* IFR TO MVFR CEILINGS AND VSBYS TODAY...LIFR POSSIBLE TONIGHT.
* NORTHEAST WINDS.
* THUNDERSTORM CHANCES TONIGHT.
LENNING
//DISCUSSION...UPDATED 12Z...
LIGHT SHOWERS/DRIZZLE HAVE REDEVELOPED AND BECOME QUITE WIDESPREAD
THIS MORNING. SHORT TERM/HI RES GUIDANCE SUGGESTS THIS WILL SLOWLY
DISSIPATE DURING THE MID/LATE MORNING SO HAVE ADDED PRECIP IN FOR
A FEW HOURS TRENDING BACK TO VCSH DUE TO LOWER UNCERTAINTY. THIS
AFTERNOON IS STILL LOOKING MAINLY DRY AS CONVECTION CURRENTLY
ACROSS NORTHEAST MO SHIFTS MORE EAST AND ALSO APPEARS TO DISSIPATE
SOME LATER THIS MORNING. FOCUS THEN SHIFTS BACK TO THE WEST/
NORTHWEST LATE THIS AFTERNOON INTO THIS EVENING. ADDITIONAL
SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER NORTHEAST
IA AND MOVE EAST/SOUTHEAST LATER THIS EVENING AND OVERNIGHT.
FAIRLY CONFIDENT CONVECTION WILL DEVELOP BUT LOWER CONFIDENCE
REGARDING MOVEMENT/LOCATION/TIMING. OPTED TO INCLUDE A TEMPO FOR
THUNDER LATE THIS EVENING/OVERNIGHT BUT REFINEMENT CAN BE EXPECTED
WITH LATER FORECASTS.
CIGS HAVE BEEN SLOW TO LOWER ACROSS ORD/MDW/DPA WITH MDW JUST NOW
INTO IFR. SLIGHTLY DRIER NORTHEAST FLOW COMBINED WITH A LACK OF
SIGNIFICANT PRECIP MAY ALLOW CIGS TO STAY ABOVE IFR TODAY BUT HAVE
MAINTAINED IFR CIGS IN THE FORECAST WITH LOW CONFIDENCE. CIGS WILL
LIKELY LOWER EITHER TO IFR OR POTENTIALLY LIFR LATER THIS EVENING
OR OVERNIGHT...ESPECIALLY IF PRECIP DOES BECOME WIDESPREAD LATER
THIS EVENING AND OVERNIGHT.
NORTHEAST WINDS WILL REMAIN IN THE 12-16KT RANGE FOR MUCH OF THE
PERIOD WITH GUSTS INTO THE LOWER/MID 20KT RANGE AT TIMES. WINDS
MAY TURN A BIT MORE EASTERLY TONIGHT WITH SPEEDS/GUSTS DIMINISHING
SOME INTO WEDNESDAY MORNING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM CONFIDENCE IN CEILING AND VSBY TRENDS.
* MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT...SHRA/TSRA. IFR. EAST/SOUTHEAST WINDS.
* THURSDAY...STRONG TSRA. MVFR. STRONG/GUSTY SOUTH/SOUTHWEST
WINDS.
* FRIDAY...DRY/VFR. STRONG/GUSTY WEST WINDS.
* SATURDAY...DRY/VFR. SOUTH WINDS. LAKE BREEZE POSSIBLE.
* SUNDAY...DRY/VFR. SOUTHEAST WINDS.
* MONDAY...CHANCE OF SHRA/TSRA. MVFR POSSIBLE. SOUTH WINDS.
&&
.MARINE...
348 AM...A FRONTAL BOUNDARY WILL REMAIN GENERALLY STATIONARY
THROUGH WEDNESDAY JUST SOUTH OF LAKE MICHIGAN...AS STRONG HIGH
PRESSURE MOVES ACROSS ONTARIO TODAY AND INTO QUEBEC TONIGHT. THIS
WILL TIGHTEN THE GRADIENT LATER TODAY INTO TONIGHT WITH A PERIOD
OF 30KTS EXPECTED. LOW PRESSURE WILL DEVELOP OVER THE CENTRAL
PLAINS WEDNESDAY NIGHT AND MOVE NORTHEAST TOWARD NORTHERN LAKE
MICHIGAN BY FRIDAY MORNING. THE EXACT TRACK OF THIS LOW REMAINS
SOMEWHAT UNCERTAIN...BUT THESE TRENDS WOULD SUPPORT THE FRONTAL
BOUNDARY MOVING NORTH AS A WARM FRONT WEDNESDAY NIGHT INTO
THURSDAY. THUS THERE IT THE POTENTIAL FOR LARGE CHANGES TO WIND
DIRECTIONS OVER PARTS OF THE LAKE FROM WEDNESDAY NIGHT INTO
THURSDAY NIGHT. EVENTUALLY WINDS WILL SHIFT WESTERLY LATE THURSDAY
NIGHT INTO FRIDAY MORNING...THEN BEGIN TO DIMINISH FRIDAY NIGHT AS
HIGH PRESSURE MOVES ACROSS THE LAKE ON SATURDAY. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 10 PM
WEDNESDAY.
&&
$$
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1043 AM CDT Tue Apr 7 2015
.UPDATE...
ISSUED AT 1040 AM CDT TUE APR 7 2015
Will update the forecast around 11 am when dense fog advisory over
central IL expires. Some patchy fog may linger into midday over areas
north of I-70 but most of the dense fog over central IL should
lift late this morning. A frontal boundary has sagged southward
into central IL near I-72 late this morning and HRRR models keeps
this boundary near I-72 into early evening. 1007 mb surface low
pressure over ne KS will track into nw MO early this evening and
tug front slowly back north during tonight. Have cooled highs
north of this boundary with upper 50s and lower 60s for highs from
Galesburg, Peoria and Bloomington north where low clouds persist.
Showers south of I-72 with thunderstorms from Litchfied sw and
some strong to severe with heavy rains from St Louis south. Severe
storms should stay along and south of I-64 today though a few
thunderstorms could affect areas from I-72 south this afternoon
along and south of the boundary. Milder highs in low to mid 70s in
sw CWA from Springfield to Terre Haute sw where some peaks of
sunshine to appear during the afternoon.
&&
.SHORT TERM...(Today)
ISSUED AT 335 AM CDT TUE APR 7 2015
A few showers and isolated thunderstorms will continue to move
across southeast Illinois early this morning. HiRes short term
models develop another area of showers and isolated thunderstorms
over northern MO and then bring them into central IL late morning
and into the afternoon. The warm front has setup and is sitting
right through central IL, north of a Quincy to Springfield to
Mattoon line, which puts half of the cwa south of the front, and
the I-74 area, including Lincoln, north of the front. So, area of
convection that does develop should follow along and just north of
the front when it arrives later this morning. So, have likely pops
in the southeast for this morning, and then slightly higher pops
in the afternoon for the west central. With front right across CWA
high temp spread with be around 15 degrees across the CWA today.
Cloud cover will also be persistent today, with some light fog
this morning. With pcpn being mainly scattered, qpf values will
not be that significant.
&&
.LONG TERM...(Tonight through Monday)
ISSUED AT 335 AM CDT TUE APR 7 2015
The warm front should become a little more active this evening and
shift north, as the first in a series of low pressure areas moves
along the frontal zone. So, higher pcpn chances will be in the
north for tonight with chance pops remaining for the rest of the
area, which will be in the warm sector. Lowest pops will be in the
south. As this first low moves east, it will drag the cold front
south through the cwa, so pops for Wed morning will be higher to
the south and only a slight chance in the north. However, the next
wave/low press area will lift out Wed afternoon and return chance
pops for the whole area. This one will lift northeast through the
area and bring much higher chances of pcpn to the CWA for late Wed
afternoon through Wed night. Per SPC day 2 outlook, there is a
slight risk of severe weather nosing into west central IL for late
Wed afternoon and into Wed night. Highest pops will be west of
I-55. Probably will be a little break Wed night after midnight,
but will not put that in just yet.
Then on Thursday, the main sfc system will lift out of the plains
with the associated mid level wave. Though there may be pcpn
ongoing Thur morning in the east, by afternoon most of the area
should be pcpn free and the atmosphere should be able to recover
before the next round of pcpn. Forecasted CAPE values will be 2000
to 2500 across a good portion of IL in the warm sector ahead of
the front. A strong upper level jet will also be pushing into the
area at the same time, so wind dynamics and shear will be
sufficient that storms will likely rotate. There is still some
uncertainty as to how this will play out Thur given the Wed night
and early morning convection, but if airmass recovers, it looks
like a line of convection will develop just west of the state late
afternoon and then move east across the state Thur evening. All
forms of severe weather look to be possible late afternoon through
the evening hours. Something to consider is that storms may be
moving at about 40-45 mph. By midnight, most of the storms should
be east of the state, but will hang on to some chance pops.
Past this system, dry conditions are expected for Fri through Sat
night. Then another system moves toward the area for Sunday
through Monday with more showers and storms.
Expecting very warm temps for Thur, but then temps will cool some
Fri and Sat, but warm back a tad for Sun and Mon.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
ISSUED AT 615 AM CDT TUE APR 7 2015
LIFR to VLIFR conditions in fog and low stratus will be the main
forecast concern early on this morning, with a gradual improvement
to MVFR cigs/vsbys by or shortly aftr 15z this morning. A stalled
frontal boundary over central Illinois will not move much today
with areas just to the south possibly seeing cigs improve to low
VFR for a time this afternoon before all areas go back to IFR
conditions again tonight. Timing and coverage of showers and
TSRA rather complicated for today so VCSH or VCTS will be included
in areas and times where we see the better threat. Surface winds
will be east to northeast at BMI and PIA with speeds of 10 to 15
kts today, with surface winds more southeast in our southern TAF
sites which were south of the stalled frontal boundary. Winds
in those locations will also average from 10 to 15 kts.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY until 11 AM CDT this morning FOR ILZ027>031-
036>038-040>057-061.
&&
$$
UPDATE...07
SHORT TERM...Auten
LONG TERM...Auten
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
105 PM CDT TUE APR 7 2015
.UPDATE...
ISSUED AT 105 PM CDT TUE APR 7 2015
FRONTAL BOUNDARY STALLED ACROSS FAR NORTHERN MO WITH TEMPERATURES
TO THE NORTH IN THE 40S WITH A NORTHEAST WIND AND TO THE SOUTH IN
THE 60S TO LOWER 70S WITH A SOUTH WIND. SPC MESO ANALYSIS
INDICATES 850 MB MOISTURE TRANSPORT WAS INCREASING OVER THIS
BOUNDARY AND SHOWERS AND A FEW THUNDERSTORMS HAVE ERUPTED IN
CENTRAL/NORTHERN IA AND INTO EXTREME SW MN. THE HRRR MODEL
INDICATES SHOWERS AND A FEW THUNDERSTORMS WILL INCREASE THE DVN
CWA AS THE AFTERNOON PROGRESSES...ESPECIALLY ACROSS OUR NORTHERN
HALF CLOSER TO THE 850 MB BOUNDARY. HAVE ALREADY UPDATED TO LOWER
TEMPERATURES SOME MORE...WITH MAXIMUM TEMPERATURES NOT REACHED
UNTIL TOWARDS EVENING AS LOW PRESSURE ADVANCES TOWARDS KANSAS CITY
AND WINDS BECOME MORE EASTERLY...RATHER THAN NORTHEAST.
UPDATE ISSUED AT 1005 AM CDT TUE APR 7 2015
HAVE MADE SEVERAL CHANGES TO THE GRIDS...ADDING AREAS OF DENSE FOG
IN OUR SOUTHERN CWA...GOING DRY THIS MORNING...LOWERING TEMPERATURES
AND DEWPOINTS BY SEVERAL DEGREES. COLD FRONT THAT MOVED THROUGH
THE CWA OVERNIGHT WAS STALLED ACROSS EXTREME NORTHERN MO. AS EXPECTED
CONVECTION FORMED SOUTH OF OUR CWA AND CURRENTLY WAS MOVING THROUGH
THE ST. LOUIS METRO AREA. SUBSIDENCE IN THE WAKE OF THE MCS WAS
KEEPING THE DVN CWA DRY THIS MORNING. IN THE MEANTIME...DEWPOINTS
IN THE 60S SOUTH OF THE BOUNDARY WAS OVERRUNNING THE FRONT AND
PRODUCING WIDESPREAD LOW STRATUS. THIS ALONG WITH A NORTHEAST WIND
WAS BRINGING DRIER AIR INTO MOST OF THE CWA AND KEEPING TEMPERATURES
COOLER THAN FORECAST. THE MODELS CONTINUE TO STRUGGLE WITH THE DRY AIR.
LOW PRESSURE IN KS WILL BE MOVING TO NEAR KANSAS CITY BY EVENING
AND INITIAL CONVECTIVE DEVELOPMENT SHOULD OCCUR AHEAD OF THIS LOW
IN NW MO EARLY THIS AFTERNOON...AND THEN SPREAD NORTHEAST INTO THE
DVN CWA AS THE AFTERNOON PROGRESSES. HOWEVER...LOW STRATUS WILL BE
PERSISTENT THROUGH THE DAY SO THUNDERSTORMS WILL BE ELEVATED AND
THERE IS THE POTENTIAL FOR SMALL HAIL ESPECIALLY THIS EVENING.
THE DENSE FOG IN OUR SOUTHERN CWA SHOULD IMPROVE BY NOON AND A
SPECIAL WEATHER STATEMENT IS IN EFFECT TO COVER THIS SITUATION.
&&
.SYNOPSIS...
ISSUED AT 252 AM CDT TUE APR 7 2015
PORTIONS OF EASTERN IOWA AND NORTHERN ILLINOIS SAW THE FIRST REAL
THUNDERSTORM ACTIVITY OF THE YEAR WITH CELLS FIRING ON THE NOSE OF
MOISTURE TRANSPORT THAT QUICKLY THEN VEERED INTO INDIANA EARLY THIS
MORNING. IN ITS WAKE...LOW LEVELS ARE SATURATED...WITH LIFT
PRODUCING SHALLOW RAINS AND DRIZZLE OVER MUCH OF THE CWA THIS
MORNING. ANOTHER BRANCH OF MOISTURE TRANSPORT IS AIMED AT NORTHWEST
MISSOURI THROUGH EASTERN NEBRASKA...WHERE NEW THUNDERSTORMS ARE
BEGINNING TO FORM. THIS NEXT THRUST OF RAINFALL IS LIKELY TO IMPACT
OUR CWA TODAY AND TONIGHT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 252 AM CDT TUE APR 7 2015
ALL ELEMENTS OF THE FORECAST ARE CHALLENGING TODAY...AS THE SHARP
CONTRAST IN TEMPERATURES ALONG THE FRONT COMBINE WITH HIGHLY
VARIABLE CONVECTIVE SIGNALS IN MODEL DATA...WHILE WE BEGIN THE
PERIOD WITH NARROW...BUT LONG BANDS OF DRIZZLE AND LIGHT RAIN. IN
ANY CASE...AS ADVERTISED...IT WILL BE A DAMP DAY...AND COULD BE
QUITE STORMY BEFORE IT IS OVER. WITH THUNDERSTORMS ALREADY FORMING
OVER NORTHWEST MISSOURI INTO SOUTHEASTERN NEBRASKA...IT APPEARS THE
CAPPING INDICATED BY THE 00Z NAM IS OVER DONE. THUS...I AM THINKING
THE 00Z ECMWF SOLUTION MAY BE CLOSEST TO REALITY TONIGHT. THERE WILL
BE AMPLE MUCAPE AVAILABLE FOR STORMS TODAY...ALL DAY AND ALL NIGHT.
HOWEVER...THE SURFACE BOUNDARY SHOULD NOT LIFT NORTH THROUGH THE
DAY...AND I FEEL STORMS WILL BE MOST ROBUST ON THE SOUTHERN FLANK OF
WHERE THE PRIMARY RAIN AREA TRACKS. THAT IS SUPPORTED BY THE 00Z
ECMWF...BUT IS ODDLY INVERTED ON SOME MODELS TODAY...SHOWING THE
MOST INTENSE CONVECTION ON THE NORTH FLANK OF RAIN...WHICH WOULD BE
VERY ODD GIVEN INFLOW FROM THE SOUTH/SOUTHWEST. THUS...WITH A LOW
TRACKING ALONG THE IOWA /MISSOURI BORDER TODAY...THAT PLACES THE CWA
INTO A SYNOPTICALLY FAVORED LOCATION FOR SHOWERS AND
THUNDERSTORMS...OCCURRING ON AN ELEVATED FRONTAL SURFACE. I WILL
INCREASE POPS FROM WEST TO EAST AFTER MID MORNING...WITH LIKELY
COVERAGE OVER THE NORTHERN 2/3RDS OF THE CWA IN THE AFTERNOON AND
EVENING. OVERNIGHT...THE BOUNDARY LINGERS OVERHEAD...WITH MUCAPE
STILL AVAILABLE...BUT THE MOISTURE TRANSPORT/LLJ SHOULD BE FOCUSED
MORE TO THE EAST BY THEN. WHILE THE NEXT ROUND OF SYNOPTIC LIFT WILL
NOT ARRIVE TO LATER WEDNESDAY. POPS WILL BE NEEDED THROUGH OUT THE
DAY DAY DUE TO THE LOW LEVEL PROCESSED CONTINUING TO PRODUCE THE
LIGHT RAIN/DRIZZLE BEFORE ANY CONVECTION ARRIVES.
TEMPERATURES TODAY WILL BE BASED ON 10 TO 15 DEGREE MODEST RISE
DIURNALLY UNDER CLOUDY SKIES. FOR THE NORTH...THIS MEANS MOST OF THE
DAY SPENT IN THE 40S...WITH EAST WINDS. THE SOUTH IS MOST LIKELY TO
SQUEEZE OUT A MILD DAY AS THE ELEVATED RAIN PROCESSES SHOULD NOT
CONSISTENTLY AFFECT THEM. TONIGHT MUCH LIKE THE CURRENT
NIGHT...LAKE ENHANCED COLD AIR WILL SWEEP SOUTH AS THE LOW PRESSURE
WAVE RIDES TO THE EAST. UPPER 30S NORTH TO LOWER 50S SOUTH ARE
SUPPORTED BY MODEL DATA AND SEEM A LIKELY FIT.
ERVIN
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 252 AM CDT TUE APR 7 2015
A PROGRESSIVE PATTERN IS SETTING UP FOR THE LONG TERM WITH A PAIR
OF UPPER LEVEL TROUGHS PROGGED THROUGH THE CENTRAL U.S. INTO EARLY
NEXT WEEK. PLENTY OF OPPORTUNITIES FOR RAIN AND A FEW CHANCES FOR
SEVERE WEATHER ARE INDICATED.
WEDNESDAY...THE UPPER LEVEL TROUGH TAKES SHAPE IN THE INTERMOUNTAIN
WEST WHILE SURFACE LOW PRESSURE AND THE LOW-LEVEL JET FOCUS ON
LIFTING A WARM FRONT INTO THE CWA. THE SURFACE BOUNDARY LINGERS IN
THE SOUTHERN CWA WHILE THE 850 MB FRONT IS FORECAST TO MOVE INTO
THE NORTHERN CWA. INSTABILITY AND SHEAR ARE SUFFICIENT FOR A
SEVERE WEATHER THREAT PRIMARILY IN THE SOUTHERN PART OF THE CWA
LATER IN THE DAY AND OVERNIGHT. THIS WILL DEPEND THE ON THE NATURE
OF CONVECTIVE DEVELOPMENT EARLIER IN THE DAY TO THE SOUTHWEST IN
THE SOMEWHAT CAPPED ENVIRONMENT. MID-LEVEL LAPSE RATES ARE VERY
STEEP WHICH WOULD INDICATE POTENTIAL FOR RAPIDLY DEVELOPING STORMS.
THURSDAY...THE UPPER LEVEL TROUGH MOVES INTO THE MIDWEST AND
INTENSIFIES WHILE THE INSTABILITY AXIS...STEEP MID-LEVEL LAPSE
RATES AND HIGH SHEAR ENVIRONMENT PERSIST OVER THE AREA. MODELS
DISAGREE SOMEWHAT IN THE DETAILS OF THE TIMING AND PRECISE TRACK
OF THE SURFACE LOW AND COLD FRONTAL PASSAGE...BUT THE CONSENSUS
FAVORS THE LOW MOVING THROUGH OR NEAR THE CWA NEAR PEAK HEATING.
THIS SUGGESTS THE FULL RANGE OF SEVERE WEATHER THREATS...AND GIVEN
THE ENVIRONMENT AND TIME OF YEAR...THIS COULD BE A SIGNIFICANT
EVENT WITH RAPIDLY DEVELOPING AND FAST-MOVING SUPERCELLS.
FRIDAY AND SATURDAY...THE TROUGH MOVES EAST AND HIGH PRESSURE
BUILDS INTO THE AREA WITH DRY AND PLEASANT WEATHER.
SUNDAY AND MONDAY...THE SECOND TROUGH BEGINS TO TAKE SHAPE IN THE
WESTERN U.S. AND MOVES INTO THE MIDWEST. INSTABILITY IS NOT TOO
IMPRESSIVE...AND CURRENT MODEL FORECASTS SEEM TO SUGGEST MORE OF
A HEAVY RAIN THREAT THAN A SEVERE THREAT. BUT THAT COULD CHANGE
BETWEEN NOW AND LATE THIS WEEKEND. WOLF
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 105 PM CDT TUE APR 7 2015
MAINLY IFR CONDS THROUGH THE TAF CYCLE ALONG WITH INCREASING
SHOWERS AND THUNDERSTORMS. NORTHEAST TO EAST WINDS 10 TO 20 KNOTS
THROUGH THE TAF CYCLE.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...HAASE
SYNOPSIS...ERVIN
SHORT TERM...ERVIN
LONG TERM...WOLF
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
225 PM CDT TUE APR 7 2015
...UPDATED FOR LONG TERM DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT TUE APR 7 2015
A COLD FRONT WAS SLOWLY PUSHING SOUTH ACROSS CENTRAL AND SOUTHWEST
KANSAS EARLY THIS MORNING. MOIST UPSLOPE FLOW TO THE NORTH OF THE
FRONT WAS RESULTING IN WIDESPREAD STRATUS AND FOG GENERALLY ALONG
AND NORTH OF A LINE FROM LACROSSE TO NEAR DODGE CITY THEN WEST
THROUGH GARDEN CITY AND SYRACUSE. AREAS IMMEDIATELY NORTH OF THE
FRONT WERE SEEING DENSE FOG DEVELOP. THE PAST SEVERAL RUNS OF THE
RUC13 AND HRRR HAVE BEEN INDICATING THIS AND THEY HAVE GENERALLY
TENDED TO MOVE IT SLOWLY SOUTHWARD BEFORE DISSIPATING IT AFTER
SUNRISE. WILL ISSUE A DENSE FOG ADVISORY FOR THIS AREA THROUGH
ABOUT 8 AM CDT.
THE FOG AND STRATUS SHOULD ERODE NORTHWARD THROUGH THE MORNING
HOURS WITH AREAS ALONG I-70 SCATTERING OUT EARLY THIS AFTERNOON.
FOR THE REST OF TODAYS FORECAST, HAVE ONLY MADE A FEW MINOR
ADJUSTMENTS. THE FRONT MAY MOVE A LITTLE MORE SOUTHWARD THIS
MORNING AS INDICATED BY THE SHORT TERM MODELS BUT THE SOUTHERN
PORTION OF THE FRONT SHOULD MIX OUT THROUGH THIS AFTERNOON. MOS
GUIDANCE IS PRETTY SIMILAR OVER WESTERN SECTIONS OF THE CWA BUT
DIFFERS MORE IN THE EAST WHERE THE COOLER MET MOS KEEPS HIGHS IN
THE UPPER 60S WHILE THE MAV GUIDANCE WARMS CENTRAL KANSAS INTO THE
MID 70S. GIVEN THAT THERE WILL BE STRATUS ERODING THROUGH PART OF
THE DAY, HAVE CONTINUED TO LEAN TOWARD THE COOLER GUIDANCE FOR
THAT AREA.
TONIGHT WILL SEE STRATUS REDEVELOPING ALONG WITH SOME PATCHY FOG
AND DRIZZLE ESPECIALLY IN THE WAKEENEY, HAYS AND LACROSSE AREAS.
MODEL SOUNDINGS ARE STILL SHOWING LOW LEVEL WARM ADVECTION
MAXIMIZED IN THAT AREA AROUND OR AFTER MIDNIGHT. IF ANY PARCELS
CAN GET LIFTED ENOUGH, THERE WILL BE SOME INSTABILITY ALOFT THAT
COULD SUPPORT A FEW THUNDERSTORMS. WILL LEAVE A MENTION OF ISOLATED
THUNDERSTORMS IN THAT AREA AS WELL.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 208 PM CDT TUE APR 7 2015
THE SHORTWAVE TROUGH MENTIONED IN THE SHORT TERM DISCUSSION WILL
PASS ACROSS CENTRAL KANSAS BY THURSDAY AFTERNOON, WITH THE
ACCOMPANYING COLD FRONT PASSING IN THE MORNING. COOL, SURFACE HIGH
PRESSURE WILL BUILD INTO WESTERN KANSAS THROUGH FRIDAY. WITH LIGHT
WINDS THURSDAY NIGHT, TEMPERATURES WILL FALL INTO THE 30S, WITH
SOME READINGS CLOSE TO FREEZING FROM DODGE CITY WESTWARD AND
NORTHWARD. HIGHS WILL BE IN THE 60S THURSDAY AND FRIDAY.
THERE IS CONSIDERABLE UNCERTAINTY WITH RESPECT TO THE EVOLUTION OF
NORTHERN AND SOUTHERN STREAM SHORTWAVE TROUGHS PROGRESSING INTO
THE DESERT SOUTHWEST AND NORTHERN ROCKIES BY SUNDAY. SURFACE
PRESSURES WILL LOWER IN THE LEE OF THE ROCKIES IN RESPONSE TO
THESE SYSTEMS LATER FRIDAY INTO SATURDAY AND SUNDAY, ALONG WITH A
GRADUAL INCREASE IN LOW LEVEL MOISTURE. A FEW RAIN SHOWERS AND
THUNDERSTORMS CAN`T BE RULED OUT STARTING SATURDAY, WITH CHANCES
LINGERING INTO SUNDAY NIGHT. COVERAGE OF SHOWER ACTIVITY IS VERY
UNCERTAIN DUE TO THE WIDE RANGE OF MODEL SOLUTIONS WITH THE UPPER
TROUGH PROGRESSING FROM THE DESERT SOUTHWEST TOWARD THE SOUTHERN
HIGH PLAINS. OVERNIGHT LOWS WILL OF COURSE BE INCREASING THROUGH
SUNDAY DUE TO THE LEE TROUGHING, SOUTH WINDS AND HIGHER DEWPOINTS.
A MORE AMPLIFIED UPPER LEVEL TROUGH WILL BEGIN TO DEVELOP OVER
THE WESTERN UNITED STATES MONDAY THROUGH WEDNESDAY OF NEXT WEEK,
RESULTING IN LEE TROUGHING ON THE HIGH PLAINS, SOUTHERLY WINDS
AND WARMER TEMPERATURES. CHANCES OF SHOWERS AND THUNDERSTORMS WILL
INCREASE BY MID TO LATE NEXT WEEK AS THE UPPER TROUGH GETS CLOSER
AND ASSOCIATED COLD FRONT APPROACHES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1119 AM CDT TUE APR 7 2015
AT 12Z TUESDAY A 500MB LOW WAS LOCATED JUST OFF THE COAST OF
NORTHERN CALIFORNIA. A SOUTHWESTERLY FLOW WAS PRESENT IN THE 700MB
AND 500MB LEVEL FROM BAJA CALIFORNIA TO THE CENTRAL PLAINS WITH
SEVERAL SUBTLE UPPER LEVEL DISTURBANCES EMBEDDED IN THIS
SOUTHWESTERLY FLOW. A SURFACE BOUNDARY EXTENDED FROM SOUTH CENTRAL
KANSAS INTO SOUTHEAST COLORADO WITH LOW CLOUDS AND STATUS OBSERVED
NORTH OF THIS BOUNDARY BASED ON SATELLITE AND SURFACE
OBSERVATIONS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 48 83 45 66 / 10 10 10 10
GCK 46 80 41 63 / 10 10 10 10
EHA 47 81 42 64 / 10 0 10 10
LBL 46 85 43 66 / 10 0 0 0
HYS 44 69 45 62 / 20 20 20 20
P28 55 86 52 72 / 10 20 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 1 PM CDT /NOON MDT/ TO 9 PM CDT /8 PM MDT/
WEDNESDAY FOR KSZ061>063-074>078-084>089.
FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR KSZ080-081-090.
&&
$$
SHORT TERM...GERARD
LONG TERM...FINCH
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS WICHITA KS
1256 PM CDT TUE APR 7 2015
...UPDATED FOR 18Z AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 334 AM CDT TUE APR 7 2015
IN THE UPPER LEVELS...WE CURRENTLY HAVE A STRONG UPPER LOW APPROACHING
NORTHERN CA WITH SW FLOW ALOFT SPREAD OVER THE ROCKIES INTO THE
PLAINS. AT THE SURFACE...LOW PRESSURE IS CENTERED OVER WEST-
CENTRAL KS/FAR EASTERN CO WITH A STATIONARY FRONT STRETCHING FROM
THE LOW PRESSURE ACROSS NORTHEAST KS AND CENTRAL MO. RICH LOW
LEVEL MOISTURE CONTINUES TO STREAM NORTH FROM THE GULF WITH
WIDESPREAD UPPER 60S DEW POINTS ACROSS EAST TX.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 334 AM CDT TUE APR 7 2015
THE UPPER LOW WILL SLOWLY TRACK EAST TODAY AND WILL BE APPROACHING
THE CENTRAL GREAT BASIN TONIGHT. A DRY LINE WILL MIX EAST TODAY
ACROSS WESTERN OK/TX WITH THE SYNOPTIC FRONT TAKING UP POSITION
FROM NE TO SW ACROSS SE KS AND INTO NORTH CENTRAL OK. THE MAIN
QUESTION WILL BE WHETHER STORMS CAN DEVELOP ALONG THESE BOUNDARIES
LATE THIS AFTERNOON/EVENING. THE NAM AND GFS HAVE BOTH BACKED OFF
ON THE AMOUNT OF CONVERGENCE OVER SE KS WITH THE RAP MUCH MORE
AGGRESSIVE IN BREAKING OUT CONVECTION LATE THIS AFTERNOON. CURRENT
THINKING IS THAT THERE IS STILL A CHANCE A STORM OR TWO COULD
DEVELOP LATE THIS AFTERNOON OVER SE KS WITH ANOTHER CHANCE FOR
ELEVATED STORMS AFTER DARK IN THIS SAME LOCATION ASSOCIATED WITH
AN INCREASE IN 850-700MB MOISTURE TRANSPORT. ANY STORM THAT
DEVELOPS EITHER THIS AFTERNOON OR TONIGHT WILL HAVE A GOOD CHANCE
TO BE SEVERE. THE TORNADO THREAT WILL BE CONDITIONAL ON STORMS
BEING ABLE TO DEVELOP IN THE 22-01Z TIME FRAME SO IT COULD STILL
BE ROOTED IN THE BOUNDARY LAYER AND THUS TAKE ADVANTAGE OF THE LOW
LEVEL SHEAR.
SIGNIFICANT SEVERE STORMS STILL LOOK POSSIBLE WED
AFTERNOON/EVENING ACROSS MAINLY SOUTH CENTRAL KS. QUITE
CONSIDERABLE DIFFERENCES HAVE SHOWN UP BETWEEN THE GFS AND NAM.
THE NAM HAS THE STATIONARY FRONT MUCH FURTHER SOUTH COMPARED TO
THE GFS WHICH WOULD LIMIT SEVERE CHANCES OVER MUCH OF CENTRAL KS.
THE NAM DOES HAVE SOME SUPPORT FROM THE 00Z ECMWF. THE MAIN
QUESTION REGARDING STORMS WED AFTERNOON/EVENING ISN`T HOW SEVERE
THEY WILL BE IF THEY DEVELOP...IT IS HOW MANY STORMS ARE ABLE TO
DEVELOP. FEEL THAT WITH SOME SHORTWAVE ENERGY FINALLY KICKING OUT
OF THE ROCKIES...AT LEAST A FEW STORMS WILL DEVELOP WED
AFTERNOON/EVENING...ESPECIALLY NEAR THE TRIPLE POINT WHERE
CONVERGENCE WILL BE MAXIMIZED. WITH 0-6KM SHEAR IN THE 45-55KT
RANGE AND CAPE IN THE 2500-3000J/KG RANGE...ANY STORMS THAT
DEVELOP WILL QUICKLY BECOME SEVERE. STORMS SHOULD BE ABLE TO STAY ISOLATED
AS THEY MOVE OFF THE DRYLINE WITH THE DEEP LAYER SHEAR
PERPENDICULAR TO THE BOUNDARY. THE NAM HAS QUITE A BIT MORE 0-3KM
CAPE COMPARED TO THE GFS BUT FEEL IT MAYBE CLOSER TO REALITY AS IT
SURPRISINGLY LOOKS TO HAVE A SLIGHTLY BETTER HANDLE ON THE LOW
LEVEL MOISTURE.
STORMS WILL TRACK EAST WED NIGHT AND AFFECT AREAS EAST OF I-135.
THE UPPER SHORTWAVE WILL QUICKLY PUSH EAST AND WILL BE OVER
WESTERN IA BY THU EVENING. THIS WILL ALLOW THE FRONT TO QUICKLY
SLIDE EAST WITH ONLY FAR SE KS HAVING A SHOT AT STORMS THU
MORNING. MEANWHILE...CENTRAL KS MAY GET IN ON SOME OF THE WARP
AROUND SHOWERS ASSOCIATED WITH THIS SYSTEM ON THU.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 334 AM CDT TUE APR 7 2015
HIGH PRESSURE IS EXPECTED TO SLIDE OVER THE PLAINS FOR FRI
ALLOWING FOR CLEAR SKIES AND TEMPS CLOSER TO SEASONAL NORMALS. AN
ACTIVE SPLIT FLOW PATTERN LOOKS TO COMMENCE FOR THE WEEKEND AS A
SERIES OF SHORTWAVES MOVE OUT OF THE ROCKIES AND ACROSS THE
PLAINS. THE IMPULSE THAT SHOULD HAVE AN IMPACT ON OUR FORECAST
AREA WILL LIFT OUT OF THE DESERT SW SAT AND INTO CENTRAL KS FOR
SUN WITH A MORE SIGNIFICANT TROUGH SWINGING ACROSS THE PLAINS FOR
MON. AT THIS TIME THE SAT NIGHT-SUN NIGHT TIME FRAME LOOKS TO HAVE
THE BEST CHANCES AT SHOWERS AND STORMS.
LAWSON
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1253 PM CDT TUE APR 7 2015
VARIABLE WEATHER WILL BE NOTED DURING THIS FORECAST PERIOD. A
SURFACE FRONT CURRENTLY RESIDES ALONG THE FLINT HILLS AND SHOULD
RETROGRADE BACK INTO SOUTH CENTRAL KANSAS ON WEDNESDAY. THE INFLUX
OF HIGHER DEWPOINTS AND THE FORECAST UPLOPE FLOW WILL PRODUCE LOW
STRATUS OR STRATOCUMULUS DURING THE OVERNIGHT AND EARLY MORNING
HOURS WEDNESDAY. VSBYS SHOULD ALSO SEE SOME RESTRICTIONS WITH THE
LOW CLOUDS. IFR CONDITIONS ARE POSSIBLE AT MOST LOCATIONS SO KEEP
AN EYE ON THE FORECAST. STRONG THUNDERSTORMS ARE POSSIBLE AT CNU
THIS EVENING AND AT MOST LOCATIONS ON WEDNESDAY.
&&
.FIRE WEATHER...
ISSUED AT 310 PM CDT MON APR 6 2015
THE MOST CRITICAL FIRE WEATHER DAY THROUGH THIS FORECAST PACKAGE
LOOKS TO BE THURSDAY.
EVEN WITH RICH LOW LEVEL MOISTURE...VERY HIGH FIRE DANGER WILL BE
IN PLACE ACROSS SOUTH CENTRAL AND PARTS OF SE KS WED DUE TO
STRONG SOUTH WINDS. WINDS WILL FLIP AROUND TO THE WEST AND
NORTHWEST ON THU AT SPEEDS IN THE 20-30 MPH RANGE BY AFTERNOON
HOURS. RH`S THU AFTERNOON WILL BE IN THE 30-40% RANGE.
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 83 64 84 55 / 10 10 30 30
HUTCHINSON 80 56 80 51 / 0 10 30 20
NEWTON 83 58 81 53 / 10 10 30 30
ELDORADO 84 65 82 59 / 10 20 30 40
WINFIELD-KWLD 85 65 83 60 / 10 10 30 30
RUSSELL 71 48 70 47 / 10 10 20 20
GREAT BEND 75 50 74 47 / 10 10 20 10
SALINA 75 52 73 50 / 10 10 30 30
MCPHERSON 79 55 77 50 / 10 10 30 30
COFFEYVILLE 83 65 81 65 / 10 20 30 40
CHANUTE 83 65 80 64 / 10 30 30 50
IOLA 83 64 79 63 / 10 30 40 50
PARSONS-KPPF 83 65 81 64 / 10 20 30 50
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1150 AM CDT TUE APR 7 2015
...UPDATED FIRE WEATHER DISCUSSION...
.SYNOPSIS...
ISSUED AT 1119 AM CDT TUE APR 7 2015
AT 12Z TUESDAY A 500MB LOW WAS LOCATED JUST OFF THE COAST OF
NORTHERN CALIFORNIA. A SOUTHWESTERLY FLOW WAS PRESENT IN THE 700MB
AND 500MB LEVEL FROM BAJA CALIFORNIA TO THE CENTRAL PLAINS WITH
SEVERAL SUBTLE UPPER LEVEL DISTURBANCES EMBEDDED IN THIS
SOUTHWESTERLY FLOW. A SURFACE BOUNDARY EXTENDED FROM SOUTH CENTRAL
KANSAS INTO SOUTHEAST COLORADO WITH LOW CLOUDS AND STATUS OBSERVED
NORTH OF THIS BOUNDARY BASED ON SATELLITE AND SURFACE
OBSERVATIONS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT TUE APR 7 2015
A COLD FRONT WAS SLOWLY PUSHING SOUTH ACROSS CENTRAL AND SOUTHWEST
KANSAS EARLY THIS MORNING. MOIST UPSLOPE FLOW TO THE NORTH OF THE
FRONT WAS RESULTING IN WIDESPREAD STRATUS AND FOG GENERALLY ALONG
AND NORTH OF A LINE FROM LACROSSE TO NEAR DODGE CITY THEN WEST
THROUGH GARDEN CITY AND SYRACUSE. AREAS IMMEDIATELY NORTH OF THE
FRONT WERE SEEING DENSE FOG DEVELOP. THE PAST SEVERAL RUNS OF THE
RUC13 AND HRRR HAVE BEEN INDICATING THIS AND THEY HAVE GENERALLY
TENDED TO MOVE IT SLOWLY SOUTHWARD BEFORE DISSIPATING IT AFTER
SUNRISE. WILL ISSUE A DENSE FOG ADVISORY FOR THIS AREA THROUGH
ABOUT 8 AM CDT.
THE FOG AND STRATUS SHOULD ERODE NORTHWARD THROUGH THE MORNING
HOURS WITH AREAS ALONG I-70 SCATTERING OUT EARLY THIS AFTERNOON.
FOR THE REST OF TODAYS FORECAST, HAVE ONLY MADE A FEW MINOR
ADJUSTMENTS. THE FRONT MAY MOVE A LITTLE MORE SOUTHWARD THIS
MORNING AS INDICATED BY THE SHORT TERM MODELS BUT THE SOUTHERN
PORTION OF THE FRONT SHOULD MIX OUT THROUGH THIS AFTERNOON. MOS
GUIDANCE IS PRETTY SIMILAR OVER WESTERN SECTIONS OF THE CWA BUT
DIFFERS MORE IN THE EAST WHERE THE COOLER MET MOS KEEPS HIGHS IN
THE UPPER 60S WHILE THE MAV GUIDANCE WARMS CENTRAL KANSAS INTO THE
MID 70S. GIVEN THAT THERE WILL BE STRATUS ERODING THROUGH PART OF
THE DAY, HAVE CONTINUED TO LEAN TOWARD THE COOLER GUIDANCE FOR
THAT AREA.
TONIGHT WILL SEE STRATUS REDEVELOPING ALONG WITH SOME PATCHY FOG
AND DRIZZLE ESPECIALLY IN THE WAKEENEY, HAYS AND LACROSSE AREAS.
MODEL SOUNDINGS ARE STILL SHOWING LOW LEVEL WARM ADVECTION
MAXIMIZED IN THAT AREA AROUND OR AFTER MIDNIGHT. IF ANY PARCELS
CAN GET LIFTED ENOUGH, THERE WILL BE SOME INSTABILITY ALOFT THAT
COULD SUPPORT A FEW THUNDERSTORMS. WILL LEAVE A MENTION OF ISOLATED
THUNDERSTORMS IN THAT AREA AS WELL.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 319 AM CDT TUE APR 7 2015
AN UPPER LEVEL LOW WILL BE POSITIONED OVER THE INTERMOUNTAIN WEST
WEDNESDAY THEN TREK EASTWARD INTO THE CENTRAL ROCKIES WEDNESDAY
NIGHT BEFORE SWINGING ACROSS NEBRASKA AND THE NORTHERN PLAINS
THURSDAY. AT THE SURFACE, AN AREA OF LOW PRESSURE WILL INTENSIFY
AS THE PREVIOUS FEATURE APPROACHES WITH A STALLED OUT FRONT
EXTENDING EASTWARD ACROSS SOUTHERN KANSAS. PATCHY FOG WILL BE
POSSIBLE NORTH OF THIS FRONT WHERE LIGHT WINDS AND AMPLE LOW LEVEL
MOISTURE WILL BE FOUND. THIS FOG IS ONLY EXPECTED TO LAST A COUPLE
OF HOURS AFTER SUNRISE WITH MOSTLY CLEAR SKIES EXPECTED FOR THE
REMAINDER OF THE DAY DUE TO MID LEVELS OF THE ATMOSPHERE BEING
DRY. VERY DRY AIR WILL BE FILTERED IN FROM THE SOUTHWEST SOUTH OF
THIS FRONT LEADING TO A DRYLINE ACROSS FAR SOUTHWESTERN KANSAS. IN
ADDITION, A FEW THUNDERSTORMS COULD FORM AHEAD OF THIS DRYLINE
DURING THE LATE AFTERNOON INTO THE EARLY EVENING. HOWEVER, ANY
CONVECTION THAT DOES FORM WILL QUICKLY MOVE EASTWARD INTO
WICHITA`S CWA. THE AREA OF LOW PRESSURE WILL QUICKLY MOVE EASTWARD
ACROSS KANSAS WEDNESDAY NIGHT WITH A COOLER NORTHWESTERLY WINDS
FELT BEHIND IT. MOISTURE WILL WRAP AROUND THIS SYSTEM BRINGING
SCATTERED SHOWERS ACROSS PORTIONS OF THE PLAINS. HOWEVER, MOST OF
THE LIFT WILL BE NORTH OF THE AREA WITH ONLY A SLIGHT CHANCE OF
SHOWERS ACROSS THE I-70 CORRIDOR EARLY THURSDAY MORNING.
A QUIET PATTERN WILL BE IN PLACE THURSDAY NIGHT THROUGH FRIDAY AS
HIGH PRESSURE BUILDS INTO THE AREA THURSDAY NIGHT THEN TREKS
SOUTHEAST OF THE AREA FRIDAY. AN AREA OF LOW PRESSURE WILL ALSO
DEVELOP ACROSS EASTERN COLORADO FRIDAY DUE TO A WEAK SHORTWAVE
MOVING THROUGH THE NORTHERN ROCKIES. SKIES LOOK TO BE MOSTLY CLEAR
DURING THIS PERIOD WITH WINDS BECOMING SOUTHERLY BY FRIDAY
AFTERNOON.
ATTENTION THEN FOCUSES ON THE WEEKEND AS AN UPPER LEVEL SHORTWAVE
INTENSIFIES ABOVE THE DESERT SOUTHWEST THEN TRACKS EASTWARD ACROSS
THE SOUTHERN ROCKIES AND SOUTHERN PLAINS. A LARGE DOME OF HIGH
PRESSURE WILL BE IN PLACE ACROSS THE EASTERN UNITED STATES AS THIS
FEATURE APPROACHES ALLOWING GULF MOISTURE TO BE PUSHED NORTH INTO
THE PLAINS. A FEW THUNDERSTORMS WILL BE POSSIBLE OVER THE WEEKEND
WITH INCREASED CLOUD COVER. A QUIET PATTERN THEN RETURNS EARLY
NEXT WEEK AS AN UPPER LEVEL RIDGE BUILDS ACROSS THE SOUTHWEST
UNITED STATES.
AS FOR TEMPERATURES, HIGHS WEDNESDAY LOOK TO RANGE FROM THE LOWER
70S NORTH OF THE FRONT TO UPPER 80S ACROSS THE KS/OK BORDER WHERE
THE VERY DRY AIR WILL BE IN PLACE. LOWS WEDNESDAY NIGHT LOOK TO
RANGE FROM AROUND 40 DEGREES ACROSS WEST CENTRAL KANSAS TO LOWER
50S ACROSS SOUTH CENTRAL KANSAS. COOLER TEMPERATURES ARE EXPECTED
BEHIND THE FRONT THURSDAY INTO FRIDAY WITH HIGHS IN THE 60S. LOWS
THURSDAY NIGHT ARE FORECASTED TO DIP INTO THE 30S WITH LOWER 40S
EXPECTED FRIDAY NIGHT. HIGHS REBOUND INTO THE 70S THIS WEEKEND
WITH LOWS IN THE 40S TO LOWER 50S. HIGHS MONDAY THEN LOOK TO BE
AROUND 70 DEGREES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1119 AM CDT TUE APR 7 2015
AT 12Z TUESDAY A 500MB LOW WAS LOCATED JUST OFF THE COAST OF
NORTHERN CALIFORNIA. A SOUTHWESTERLY FLOW WAS PRESENT IN THE 700MB
AND 500MB LEVEL FROM BAJA CALIFORNIA TO THE CENTRAL PLAINS WITH
SEVERAL SUBTLE UPPER LEVEL DISTURBANCES EMBEDDED IN THIS
SOUTHWESTERLY FLOW. A SURFACE BOUNDARY EXTENDED FROM SOUTH CENTRAL
KANSAS INTO SOUTHEAST COLORADO WITH LOW CLOUDS AND STATUS OBSERVED
NORTH OF THIS BOUNDARY BASED ON SATELLITE AND SURFACE
OBSERVATIONS.
&&
.FIRE WEATHER...
ISSUED AT 1149 AM CDT TUE APR 7 2015
A DRYLINE WILL BE LOCATED ACROSS SOUTH CENTRAL KANSAS BY LATE DAY
WEDNESDAY. UNSEASONABLY WARM CONDITIONS COMBINED WITH DRY AIR
SPREADING EAST ACROSS SOUTHWEST KANSAS BEHIND THIS DRYLINE
WEDNESDAY AFTERNOON WILL RESULT IN RELATIVE HUMIDITY VALUES
FALLING BACK INTO THE 10 TO 15 PERCENT RANGE. THESE LOW RELATIVE
HUMIDITIES ALONG WITH GUSTY SOUTHWEST WINDS OF 20 TO 25 MPH WILL
CREATE A FAVORABLE ENVIRONMENT FOR ANY OPEN FIRES TO SPREAD
QUICKLY AND BE DIFFICULT TO CONTROL. AS A RESULT WILL BE UPGRADING
THE MOST OF THE FIRE WEATHER WATCH TO A RED FLAG WARNING. OUT DOOR
BURNING ON WEDNESDAY SHOULD BE AVOIDED.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 79 48 83 46 / 0 10 10 10
GCK 77 46 80 42 / 0 10 10 10
EHA 83 47 81 43 / 0 10 0 10
LBL 84 46 85 44 / 0 10 0 0
HYS 69 44 69 46 / 10 20 20 20
P28 83 55 86 53 / 10 10 20 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 1 PM CDT /NOON MDT/ TO 9 PM CDT /8 PM MDT/
WEDNESDAY FOR KSZ061>063-074>078-084>089.
FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR KSZ080-081-090.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...GERARD
LONG TERM...HOVORKA_42
AVIATION...BURGERT
FIRE WEATHER...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1121 AM CDT TUE APR 7 2015
...UPDATED SYNOPSIS AND AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 1119 AM CDT TUE APR 7 2015
AT 12Z TUESDAY A 500MB LOW WAS LOCATED JUST OFF THE COAST OF
NORTHERN CALIFORNIA. A SOUTHWESTERLY FLOW WAS PRESENT IN THE 700MB
AND 500MB LEVEL FROM BAJA CALIFORNIA TO THE CENTRAL PLAINS WITH
SEVERAL SUBTLE UPPER LEVEL DISTURBANCES EMBEDDED IN THIS
SOUTHWESTERLY FLOW. A SURFACE BOUNDARY EXTENDED FROM SOUTH CENTRAL
KANSAS INTO SOUTHEAST COLORADO WITH LOW CLOUDS AND STATUS OBSERVED
NORTH OF THIS BOUNDARY BASED ON SATELLITE AND SURFACE
OBSERVATIONS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT TUE APR 7 2015
A COLD FRONT WAS SLOWLY PUSHING SOUTH ACROSS CENTRAL AND SOUTHWEST
KANSAS EARLY THIS MORNING. MOIST UPSLOPE FLOW TO THE NORTH OF THE
FRONT WAS RESULTING IN WIDESPREAD STRATUS AND FOG GENERALLY ALONG
AND NORTH OF A LINE FROM LACROSSE TO NEAR DODGE CITY THEN WEST
THROUGH GARDEN CITY AND SYRACUSE. AREAS IMMEDIATELY NORTH OF THE
FRONT WERE SEEING DENSE FOG DEVELOP. THE PAST SEVERAL RUNS OF THE
RUC13 AND HRRR HAVE BEEN INDICATING THIS AND THEY HAVE GENERALLY
TENDED TO MOVE IT SLOWLY SOUTHWARD BEFORE DISSIPATING IT AFTER
SUNRISE. WILL ISSUE A DENSE FOG ADVISORY FOR THIS AREA THROUGH
ABOUT 8 AM CDT.
THE FOG AND STRATUS SHOULD ERODE NORTHWARD THROUGH THE MORNING
HOURS WITH AREAS ALONG I-70 SCATTERING OUT EARLY THIS AFTERNOON.
FOR THE REST OF TODAYS FORECAST, HAVE ONLY MADE A FEW MINOR
ADJUSTMENTS. THE FRONT MAY MOVE A LITTLE MORE SOUTHWARD THIS
MORNING AS INDICATED BY THE SHORT TERM MODELS BUT THE SOUTHERN
PORTION OF THE FRONT SHOULD MIX OUT THROUGH THIS AFTERNOON. MOS
GUIDANCE IS PRETTY SIMILAR OVER WESTERN SECTIONS OF THE CWA BUT
DIFFERS MORE IN THE EAST WHERE THE COOLER MET MOS KEEPS HIGHS IN
THE UPPER 60S WHILE THE MAV GUIDANCE WARMS CENTRAL KANSAS INTO THE
MID 70S. GIVEN THAT THERE WILL BE STRATUS ERODING THROUGH PART OF
THE DAY, HAVE CONTINUED TO LEAN TOWARD THE COOLER GUIDANCE FOR
THAT AREA.
TONIGHT WILL SEE STRATUS REDEVELOPING ALONG WITH SOME PATCHY FOG
AND DRIZZLE ESPECIALLY IN THE WAKEENEY, HAYS AND LACROSSE AREAS.
MODEL SOUNDINGS ARE STILL SHOWING LOW LEVEL WARM ADVECTION
MAXIMIZED IN THAT AREA AROUND OR AFTER MIDNIGHT. IF ANY PARCELS
CAN GET LIFTED ENOUGH, THERE WILL BE SOME INSTABILITY ALOFT THAT
COULD SUPPORT A FEW THUNDERSTORMS. WILL LEAVE A MENTION OF ISOLATED
THUNDERSTORMS IN THAT AREA AS WELL.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 319 AM CDT TUE APR 7 2015
AN UPPER LEVEL LOW WILL BE POSITIONED OVER THE INTERMOUNTAIN WEST
WEDNESDAY THEN TREK EASTWARD INTO THE CENTRAL ROCKIES WEDNESDAY
NIGHT BEFORE SWINGING ACROSS NEBRASKA AND THE NORTHERN PLAINS
THURSDAY. AT THE SURFACE, AN AREA OF LOW PRESSURE WILL INTENSIFY
AS THE PREVIOUS FEATURE APPROACHES WITH A STALLED OUT FRONT
EXTENDING EASTWARD ACROSS SOUTHERN KANSAS. PATCHY FOG WILL BE
POSSIBLE NORTH OF THIS FRONT WHERE LIGHT WINDS AND AMPLE LOW LEVEL
MOISTURE WILL BE FOUND. THIS FOG IS ONLY EXPECTED TO LAST A COUPLE
OF HOURS AFTER SUNRISE WITH MOSTLY CLEAR SKIES EXPECTED FOR THE
REMAINDER OF THE DAY DUE TO MID LEVELS OF THE ATMOSPHERE BEING
DRY. VERY DRY AIR WILL BE FILTERED IN FROM THE SOUTHWEST SOUTH OF
THIS FRONT LEADING TO A DRYLINE ACROSS FAR SOUTHWESTERN KANSAS. IN
ADDITION, A FEW THUNDERSTORMS COULD FORM AHEAD OF THIS DRYLINE
DURING THE LATE AFTERNOON INTO THE EARLY EVENING. HOWEVER, ANY
CONVECTION THAT DOES FORM WILL QUICKLY MOVE EASTWARD INTO
WICHITA`S CWA. THE AREA OF LOW PRESSURE WILL QUICKLY MOVE EASTWARD
ACROSS KANSAS WEDNESDAY NIGHT WITH A COOLER NORTHWESTERLY WINDS
FELT BEHIND IT. MOISTURE WILL WRAP AROUND THIS SYSTEM BRINGING
SCATTERED SHOWERS ACROSS PORTIONS OF THE PLAINS. HOWEVER, MOST OF
THE LIFT WILL BE NORTH OF THE AREA WITH ONLY A SLIGHT CHANCE OF
SHOWERS ACROSS THE I-70 CORRIDOR EARLY THURSDAY MORNING.
A QUIET PATTERN WILL BE IN PLACE THURSDAY NIGHT THROUGH FRIDAY AS
HIGH PRESSURE BUILDS INTO THE AREA THURSDAY NIGHT THEN TREKS
SOUTHEAST OF THE AREA FRIDAY. AN AREA OF LOW PRESSURE WILL ALSO
DEVELOP ACROSS EASTERN COLORADO FRIDAY DUE TO A WEAK SHORTWAVE
MOVING THROUGH THE NORTHERN ROCKIES. SKIES LOOK TO BE MOSTLY CLEAR
DURING THIS PERIOD WITH WINDS BECOMING SOUTHERLY BY FRIDAY
AFTERNOON.
ATTENTION THEN FOCUSES ON THE WEEKEND AS AN UPPER LEVEL SHORTWAVE
INTENSIFIES ABOVE THE DESERT SOUTHWEST THEN TRACKS EASTWARD ACROSS
THE SOUTHERN ROCKIES AND SOUTHERN PLAINS. A LARGE DOME OF HIGH
PRESSURE WILL BE IN PLACE ACROSS THE EASTERN UNITED STATES AS THIS
FEATURE APPROACHES ALLOWING GULF MOISTURE TO BE PUSHED NORTH INTO
THE PLAINS. A FEW THUNDERSTORMS WILL BE POSSIBLE OVER THE WEEKEND
WITH INCREASED CLOUD COVER. A QUIET PATTERN THEN RETURNS EARLY
NEXT WEEK AS AN UPPER LEVEL RIDGE BUILDS ACROSS THE SOUTHWEST
UNITED STATES.
AS FOR TEMPERATURES, HIGHS WEDNESDAY LOOK TO RANGE FROM THE LOWER
70S NORTH OF THE FRONT TO UPPER 80S ACROSS THE KS/OK BORDER WHERE
THE VERY DRY AIR WILL BE IN PLACE. LOWS WEDNESDAY NIGHT LOOK TO
RANGE FROM AROUND 40 DEGREES ACROSS WEST CENTRAL KANSAS TO LOWER
50S ACROSS SOUTH CENTRAL KANSAS. COOLER TEMPERATURES ARE EXPECTED
BEHIND THE FRONT THURSDAY INTO FRIDAY WITH HIGHS IN THE 60S. LOWS
THURSDAY NIGHT ARE FORECASTED TO DIP INTO THE 30S WITH LOWER 40S
EXPECTED FRIDAY NIGHT. HIGHS REBOUND INTO THE 70S THIS WEEKEND
WITH LOWS IN THE 40S TO LOWER 50S. HIGHS MONDAY THEN LOOK TO BE
AROUND 70 DEGREES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1119 AM CDT TUE APR 7 2015
AT 12Z TUESDAY A 500MB LOW WAS LOCATED JUST OFF THE COAST OF
NORTHERN CALIFORNIA. A SOUTHWESTERLY FLOW WAS PRESENT IN THE 700MB
AND 500MB LEVEL FROM BAJA CALIFORNIA TO THE CENTRAL PLAINS WITH
SEVERAL SUBTLE UPPER LEVEL DISTURBANCES EMBEDDED IN THIS
SOUTHWESTERLY FLOW. A SURFACE BOUNDARY EXTENDED FROM SOUTH CENTRAL
KANSAS INTO SOUTHEAST COLORADO WITH LOW CLOUDS AND STATUS OBSERVED
NORTH OF THIS BOUNDARY BASED ON SATELLITE AND SURFACE
OBSERVATIONS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 80 49 84 46 / 0 10 10 10
GCK 79 46 81 42 / 0 10 10 10
EHA 83 47 81 43 / 0 10 0 10
LBL 85 46 85 44 / 0 10 0 0
HYS 70 46 69 46 / 10 20 20 20
P28 85 55 88 53 / 10 10 20 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR KSZ061>063-074>078-080-081-084>090.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...GERARD
LONG TERM...HOVORKA_42
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS JACKSON KY
230 PM EDT TUE APR 7 2015
.UPDATE...
ISSUED AT 1135 AM EDT TUE APR 7 2015
THUNDERSTORM COMPLEX WHICH RESULTED IN A FEW FLOODING REPORTS IN
OUR SOUTHERN COUNTIES IS EXITING INTO TN AND VA. OTHER
THUNDERSTORMS IN THE LMK AREA WERE HEADING TOWARD OUR NORTHERN
COUNTIES...BUT WERE WEAKENING. HAVE ADJUSTED NEAR TERM POPS FOR
THE OBSERVED RADAR TRENDS. WITH A MOIST AIR MASS...WARM AIR
ADVECTION...A FRONTAL BOUNDARY JUST TO OUR NORTH...NO SIGNIFICANT
CAP...AND WEAK IMPULSES PASSING THROUGH...
REDEVELOPMENT/INTENSIFICATION WILL BE A POSSIBILITY AS SOME
LIMITED DESTABILIZATION OCCURS THIS AFTERNOON. CONFIDENCE IN
TIMING AND LOCATION IS LOW. HAVE LEANED TOWARD THE HRRR SOLUTION
THIS AFTERNOON INTO TONIGHT...BUT KEPT THE FORECAST FAIRLY
GENERALIZED.
UPDATE ISSUED AT 800 AM EDT TUE APR 7 2015
DID A QUICK UPDATE TO THE GRIDS TO REFLECT THE LATEST RADAR TRENDS
WITH THE SWATH OF SHOWERS AND EMBEDDED THUNDERSTORMS MOVING
THROUGH THE CWA. ALSO FINE TUNED THE TEMPS AND TD FOR THE LATEST
OBS AND TRENDS. THE UPDATED GRIDS HAVE BEEN SENT TO THE NDFD AND
WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 340 AM EDT TUE APR 7 2015
06Z SFC ANALYSIS SHOWS LOW PRESSURE OVER THE CENTRAL PLAINS WITH A
WARM FRONT SLUNG EAST...RUNNING INTO THE OHIO VALLEY BEFORE
BECOMING A STATIONARY BOUNDARY JUST NORTH OF EASTERN KENTUCKY.
THIS PLACES THE CWA IN A WARM AND MOIST ENVIRONMENT AS SOUTH WINDS
SUPPORT PWS APPROACHING 1.5 INCHES. JUST NOW A FEW SHOWERS ARE
STARTING TO POP OVER THE SOUTHERN PARTS OF THE AREA AFTER A
RELATIVELY QUIET EVENING AND START TO THE NIGHT. ADDITIONAL
CONVECTION TO THE WEST IS PUSHING EAST JUST SOUTH OF THE WARM
FRONT...CURRENTLY MOVING THROUGH NORTHWESTERN KENTUCKY AND
SOUTHERN ILLINOIS/INDIANA. UNDER MOSTLY CLOUDY SKIES OVERNIGHT...
MOST OF EASTERN KENTUCKY IS SEEING TEMPERATURES FROM 55 TO 60
DEGREES WITH SOME EASTERN VALLEYS SLIGHTLY COOLER AND WARMER
CONDITIONS IN THE FAR SOUTHWEST. DEW POINTS...MEANWHILE...HAVE
COME UP INTO THE 50S FOR THE AREA...A DRAMATIC REVERSAL OF THIS
PAST WEEKEND/S DRYNESS.
THE MODELS ARE IN FAIRLY GOOD AGREEMENT ALOFT THROUGH THE SHORT
TERM AS A SERIES OF WEAK TO MODERATE WAVES PASS THROUGH THE OHIO
VALLEY IN BROAD...SLIGHTLY SOUTHWEST...FLOW ON THE NORTHERN
FRINGE OF THE FLAT SOUTHEAST RIDGE. EACH MODEL HAS A SLIGHTLY
DIFFERENT HANDLE ON THE TIMING AND TRACK OF THESE WAVES LOWERING
CONFIDENCE IN ANY PARTICULAR SOLUTION. NEVERTHELESS...THE ENERGY
WILL BE THERE...ALONG WITH PLENTY OF FUEL IN THE FORM OF HEAT AND
HUMIDITY...FOR CONVECTIVE DEVELOPMENT BASED MORE ON THESE MID
LEVEL RIPPLES THAN STRICTLY THE DIURNAL CYCLE. GIVEN THE SMALL
NATURE OF THE FEATURES THAT WILL DRIVE THE CONVECTION OVER THE
NEXT COUPLE OF DAYS HAVE RELIED MORE CLOSELY ON THE HIGHER
RESOLUTION HRRR AND NAM12 FOR THE WEATHER DETAILS.
SENSIBLE WEATHER WILL FEATURE AN UNSEASONABLY WARM AND HUMID
PERIOD WITH OCCASIONAL ROUNDS OF SHOWERS AND THUNDERSTORMS
EXPECTED DUE TO EASTERN KENTUCKY/S POSITION SOUTH OF A STALLED
FRONTAL BOUNDARY TO THE NORTH AND IMPULSES PASSING THROUGH FROM
ALOFT. THE FIRST OF THESE WILL PASS THIS MORNING WITH A ROUND OF
CONVECTION EXPECTED FOLLOWED BY A POTENTIAL FOR ANOTHER LATE THIS
AFTERNOON AND INTO THE EVENING. THE NAM12 WOULD THEN HAVE A LULL
UNTIL DAYTIME WEDNESDAY WHEN ANOTHER WAVE IS EXPECTED TO DEVELOP
AND PASS OVER THE STATE. SEVERE WEATHER WILL BE A POSSIBILITY
TODAY WITH EITHER OF THESE CLUSTERS DEPENDING ON UPSCALE GROWTH
AND...FOR THE LATTER...SFC HEATING BETWEEN SYSTEMS. GIVEN THE
RELATIVELY HIGH PWS...HEAVY RAIN WILL BE A POSSIBILITY AS WELL AND
MAY PRIME THE AREA FOR LOCALIZED FLOOD CONCERNS BEFORE THE FRONTAL
STRUCTURE MOVES OUT OF THE REGION AT WEEK/S END. WILL HIGHLIGHT
BOTH THE SVR AND HEAVY RAIN CONCERNS IN THE FORTHCOMING HWO.
USED THE SHORTBLEND COMPOSITE MODEL AS A STARTING POINT FOR THE
WINDS/T/TD GRIDS THROUGH THE FIRST 18-24 HOURS AND THE SUPERBLEND
THEREAFTER. DID MAKE SOME MINOR ADJUSTMENTS BASED ON TERRAIN FOR
TONIGHT/S TEMPERATURES. AS FOR POPS...ENDED UP CLOSEST TO THE MET
VALUES TODAY AND TONIGHT...BUT HIGHER FOR MIDDAY WEDNESDAY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 335 AM EDT TUE APR 7 2015
MULTIPLE WAVES WILL CONTINUE TO RIDE UP AND ALONG A RIDGING PATTERN
ACROSS THE EASTERN CONUS THROUGH THE SHORT TERM AND TO START OUT THE
EXTENDED PORTION OF THE FORECAST. MEANWHILE A STRONG SHORTWAVE OVER
THE ROCKIES WILL BEGIN TO SHIFT EASTWARD BY 0Z THURSDAY...CREATING
LONGWAVE TROUGHING OVER THE WESTERN CONUS. EXPECT THIS SHORTWAVE TO
CONTINUE ON ITS TREK EAST AND NORTHEASTWARD THROUGH THE DAY THURSDAY
AND INTO THE DAY FRIDAY...WITH DECREASING HEIGHTS EXPECTED ACROSS
THE OHIO RIVER VALLEY DURING THIS TIME.
AT THE SURFACE...KY WILL FIND ITSELF UNDER THE INFLUENCE OF A
STALLED WARM FRONT WEDNESDAY NIGHT INTO THURSDAY MORNING...WHICH
WILL LIKELY BE POSITIONED ACROSS THE NORTHERN PORTION OF THE CWA.
THIS WILL RESULT IN CONTINUED SHOWERS AND THUNDERSTORMS...ESPECIALLY
ACROSS THE NORTHERN HALF OF THE STATE. TO OUR EAST...A SURFACE LOW
WILL CONTINUE TO DEVELOP BELOW AND JUST AHEAD OF THE ABOVE MENTIONED
SHORTWAVE...AND FOLLOW ITS TRACK NORTHEASTWARD THROUGH THE DAY
THURSDAY. BY 0Z FRIDAY...THE WARM FRONT WILL SHIFT EAST AND ENABLE A
STRONG COLD FRONT...CONNECTED TO THIS LOW PRESSURE SYSTEM...TO PUSH
FROM WEST TO EAST ACROSS KY. GIVEN THE LATEST GFS FORECAST...THE
BOUNDARY SHOULD ENTER INTO EASTERN KY SOMETIME FRIDAY
AFTERNOON...ENHANCING SHOWER AND THUNDERSTORM ACTIVITY THROUGH THE
MORNING JUST AHEAD OF THE FRONT...AND EXIT EAST OF THE STATE BETWEEN
21Z FRIDAY AND 0Z SATURDAY. ONCE IT DOES...KY WILL BE IN A MORE
ZONAL UPPER LEVEL FLOW WITH SURFACE HIGH PRESSURE BUILDING ACROSS
THE STATE. SURFACE WINDS WILL ONCE AGAIN BECOME MORE
NORTHERLY...CAUSING TEMPERATURES TO DROP BACK INTO THE 40S OVERNIGHT
FRIDAY NIGHT/SATURDAY MORNING...AND IN THE MID 60S BY SATURDAY
AFTERNOON.
EXPECT THIS HIGH PRESSURE TO KEEP DRY WEATHER IN PLAY THROUGH MUCH
OF THE WEEKEND...WITH TEMPERATURES EXPECTED TO REBOUND BACK INTO THE
LOW 70S BY MONDAY. BY THIS TIME...A LOW PRESSURE SYSTEM OVER THE
SOUTHERN PLAINS WILL MOVE NE ONCE MORE AND PUSH A WARM FRONT
NORTHWARD INTO THE REGION...ALLOWING UNSTABLE WARM GULF MOISTURE TO
FLOW BACK INTO THE CWA AND ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS TO DEVELOP LATE SUNDAY AND SUNDAY NIGHT. THIS WILL BE
ENHANCED AS THE FOLLOWING COLD FRONT BEGINS FROM WEST TO EAST ACROSS
THE STATE ONCE MORE DURING THE DAY MONDAY AND MONDAY NIGHT. EXACT
TIMING OF THIS FRONTAL PASSAGE...AS WELL AS THE ONSET AND STRENGTH OF
THE PRECIPITATION ARE STILL FAR ENOUGH OUT IN THE FORECAST THAT
RELYING ON A MODEL BLEND WAS THE METHOD OF CHOICE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 230 PM EDT TUE APR 7 2015
SHOWERS AND A FEW RUMBLES OF THUNDER WERE ONGOING OVER PORTIONS OF
THE FORECAST AREA AT THE START OF THE PERIOD...ESPECIALLY NORTH OF
A LINE FROM MOUNT STERLING TO PAINTSVILLE. WILL LOOK FOR MOST OF
THE ACTIVITY TO WEAKEN AND MOVE OUT TO THE EAST DURING THE COURSE
OF THE AFTERNOON. ADDITIONAL SHOWERS AND THUNDERSTORMS WILL BE
POSSIBLE DURING THE FORECAST PERIOD. HOWEVER...THERE IS LOW
CONFIDENCE AS TO WHEN/WHERE THEY MAY OCCUR. FOR THAT REASON...HAVE
ONLY USED VCTS AFTER THIS AFTERNOON. IN TERMS OF CONDITIONS...MVFR
COULD OCCUR WITH THE PRECIP. OUTSIDE OF THIS...WILL LOOK FOR
LARGELY VFR. THE TAFS ARE WRITTEN IN A GENERALIZED FASHION DUE TO
LOW FORECAST CONFIDENCE.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
120 PM EDT Tue Apr 7 2015
...Updated Aviation Discussion...
...Forecast Update...
Issued at 1149 AM EDT Tue Apr 7 2015
The complex of showers and thunderstorms will continue to push east
along the I-64 corridor for the next hour or two. They are looking
less organized but will still be capable of frequent cloud to ground
lightning and brief heavy rainfall.
Focus is now shifting to the west where the previous supercell has
now evolved into a growing linear segment crossing the Mississippi
River near St. Louis. This feature is expected to continue ESE or SE
toward our region through the early afternoon, growing as it does
so. Already seeing good destabilization across west central KY where
some clearing has occurred, and do expect a 1500 - 2500 J/KG
instability axis to setup along and west of I-65 during peak
heating. Some of the southern Indiana counties where this morning`s
complex passed may struggle to get as unstable. Will also note that
0-6 km bulk shear should range between 30-40 knots, sufficient for
continued organization. Forecast sounding are quite impressive if
they verify and would suggest a severe wind and hail threat with the
strongest storms. In collaboration with the Storm Prediction Center,
mention of an upgrade to a slight risk is a possibility across
western portions of our CWA this afternoon. Right now the best
timing for the CWA looks to be between 3 PM EDT and 9 PM EDT.
Do want to mention that another round of heavy rain will accompany
the potential severe threat with this next round of convection.
Depending on where heaviest rain falls, more hydro products may be
needed.
Previous Update...
Issued at 919 AM EDT Tue Apr 7 2015
Storms will wind down along the I-64 corridor through the late
morning hours. However, will have to keep an eye on the stronger
cluster currently over southern Indiana as it moves ESE toward the
Kentucky Bluegrass region. Very intense rainfall has left 2 to 3
inches in a short amount of time across small portions of southern
Indiana and will keep the Flash Flood Warning going across
Orange/Washington counties for the time being. Have upped pops and
QPF to account for this cluster. Hail will also be possible with
this storm.
Focus will then shift to this afternoon and evening as another round
of storms will be possible. Looking upstream, an impressive
supercell is tracking ESE along I-70 and the warm front toward St.
Louis. This feature is expected to turn more SE along the
instability gradient through the late morning and early afternoon,
and grow into a more linear complex. Do expect to get some partial
clearing which will aid an already destabilizing atmosphere. SREF
probabilities of greater than 1000 J/KG of CAPE this afternoon are
likely along and west of I-65. 0-6 km shear values between 30 and 40
knots this afternoon would also support organization. Will have to
watch how things progress through the late morning as there is some
concern for strong to severe storms this afternoon and evening.
The 06z NAM and HRRR are handling the current situation pretty well.
However the NAM is a bit too far north and a couple hours slow. Did
the afternoon forecast based off this solution with adjustments for
timing placement. Adjusted QPF upward as well in anticipation of the
afternoon storms.
.SHORT TERM (Now through Wednesday)...
Issued at 257 AM EDT Tue Apr 7 2015
The GFS, 4km NAM, and, to a lesser extent, SPC SREF, have a good
handle on an area of showers and embedded thunderstorms moving from
southeast Illinois into the lower and middle Ohio Valley at 07Z
this morning. The storms are ahead of an upper level disturbance
coming in from the lower and middle Mississippi Valley. This
convective complex will continue to spread eastward this morning
along and a few counties either side of the I-64 corridor. Though
the showers and storms will mostly be garden variety, a few gusts of
wind or instances of small hail in the strongest cores can`t be
entirely ruled out.
The morning showers and storms will have moved off to the east by
early afternoon. This afternoon another weak upper wave will come
in from the west. Though some stabilization will occur over
southern Indiana and northern Kentucky from the morning rain,
additional scattered shower and thunderstorm development will be
possible, albeit with less coverage than what we see this morning.
Again, a few strong storms will be possible.
With plenty of moisture available, locally heavy downpours will be
possible with the thunderstorms. The cells should be progressive,
but there will be some training this morning in southern Indiana
and north central Kentucky.
Decided to drop max temps a few degrees in the north where more rain
and clouds will prevail through the morning hours, but still have
70s everywhere for highs this afternoon.
After a lull this evening, more shower and thunderstorm development
will be possible late tonight as the next weak upper wave comes in
from the west after midnight. Low temperatures will be in the lower
and middle 60s.
The relatively low confidence forecast today and tonight becomes
even lower on Wednesday. We will remain in the same warm, juicy air
mass as today, south of a stationary surface front from Illinois to
Ohio. The late night showers/storms tonight will likely persist
into Wednesday morning, with redevelopment possible Wednesday
afternoon especially near any leftover convective boundaries from
the morning activity. Highs should be in the middle and upper
70s...maybe an 80 degree reading if we can get enough sunshine in
the afternoon.
.LONG TERM (Wednesday Night through Monday)...
Issued at 235 AM EDT Tue Apr 7 2015
The focus in the long term period is on thunderstorm chances/timing
Wednesday night through Friday.
The upper level pattern Wednesday night is expected to feature a
digging trough from the Rockies into the central Plains with
downstream ridging extending from the Gulf Coast through the
southern Great Lakes region. At the surface, a warm and moist air
mass characterized by dewpoints in the 60s will be in place thanks
to a developing surface low to our west. Stronger southerly flow
should make for a mild night with lows only falling into the mid
60s.
The focus for thunderstorm initiation Wednesday night is favored to
our west where the strengthening low-level jet impinges on an
east-west boundary across Illinois. These storms could then take an
east/southeast track across portions of the area. Strength/severity
a bit more uncertain as elevated instability wanes considerably
and effective shear is not as impressive but a few elevated stronger
storms would be possible. Kept POPs in the 30-50 percent range,
tapered highest to lowest from southern Indiana to southern Kentucky
respectively.
The main upper level trough will advance eastward Thursday as the
surface low deepens/lifts to Wisconsin by Thursday night. 07.00z
guidance remained overall similar to earlier runs in its
progression, bringing the cold front through the local area late
Thursday night into Friday morning. Scattered showers and
thunderstorms are possible ahead of the main system though coverage
isn`t expected to be very high. Decaying strong thunderstorms look
to be approaching our western borders during the late evening, and
if enough elevated instability remains present, a marginal wind
threat exists. Overall, the system looks fairly progressive,
limiting the training heavy rainfall threat as well.
Ahead of the front, a very warm air mass will be in place. Depending
on how cloud cover fares, we`ll be approaching 80 degrees in most
spots Thursday. A mild night would then set up with lows in the mid
60s to near 70 degrees.
Friday looks to be our transition day as the front sweeps across the
area. Will keep chance POPs in the morning to early afternoon hours,
especially east of I-65 before clearing conditions work in for the
evening. Seasonable, pleasant and mostly sunny conditions thanks to
surface high pressure expected Saturday into the first part of
Sunday. A model consensus approach gives highs in the mid to upper
60s Saturday and upper 60s to low 70s Sunday.
Increasing moisture and southerly return flow sets up Sunday night
into early next week as the surface high moves to our east. A slow
ramp up in POPs, still chance, will be advertised as deterministic
models show another system lifting through the central Plains to
lower Great Lakes. Seasonable to above seasonable temperatures look
reasonable at this time.
&&
.AVIATION (18Z TAF Update)...
Updated at 120 PM EDT Tue Apr 7 2015
We`re in a relative lull with convection with only some storms
hanging around LEX for another hour or two. Warm sector has become
firmly established over the area and should see mostly VFR
conditions as skies partially clear through much of the afternoon.
Expect a steady south wind around 10 mph with a few higher gusts
possible.
Focus is upstream on the next convective complex set to move into
the TAF sites from late afternoon through evening. Best timing at
SDF is expected between 5 and 10 PM EDT where visibilities could
drop into the IFR range in heavier thunderstorms. Stronger wind
gusts and some hail will also be possible with the strongest storms.
LEX/BWG should see weaker convection and a couple hours later than
at SDF. There should be another relative lull overnight where VFR
conditions are expected to prevail. More convection possible
again Wednesday morning. Confidence is low beyond this evening.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........BJS
Short Term.....13
Long Term......ZT
Aviation.......BJS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
448 PM EDT TUE APR 7 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 448 PM EDT TUE APR 7 2015
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW THAT THE CONFLUENT FLOW
THAT HAS BEEN ACROSS THE UPPER GREAT LAKES IS SHIFTING E AND NE AS
THE NRN STREAM TROF OVER ERN CANADA IS SLOWLY LIFTING OUT AND SRN
BRANCH RIDGE OVER THE PLAINS DOWNSTREAM OF TROF ALONG THE W COAST IS
GRADUALLY BUILDING NE AND E. SFC HIGH PRES SUPPORTED BY THE
CONFLUENT FLOW ALOFT RIDGES W-E ACROSS NRN ONTARIO INTO SRN QUEBEC.
ALTHOUGH THERE HAVE BEEN SOME MID-LEVEL RADAR RETURNS ACROSS THE
FCST AREA...ESPECIALLY EARLIER TODAY...THE VERY DRY AIR AT THE LOWER
LEVELS EMANATING FROM THE HIGH PRES RIDGE HAS RESULTED IN DRY
WEATHER ACROSS THE FCST AREA TODAY. IN FACT...THE KEWEENAW AND ERN
UPPER MI HAVE ENJOYED MOSTLY SUNNY SKIES FOR A GOOD PART OF THE DAY.
TO THE S...WARM FRONT/STATIONARY FRONT EXTENDS FROM KS ACROSS CNTRL
IL INTO NRN OHIO. TO THE W AND SW...A WELL-DEFINED SHORTWAVE IS
TRACKING ENE ACROSS SE SASKATCHEWAN WHILE WEAKER WAVES ARE MOVING
ACROSS WY/CO AND OUT ACROSS THE PLAINS. THESE FEATURES WILL PLAY A
ROLE IN A CHALLENGING FCST HERE TONIGHT/WED.
INITIALLY...EXPECT DRY WEATHER TO PREVAIL THIS EVENING UNDER A
CONTINUED FEED OF DRY LOW-LEVEL AIR FROM THE E AND NE. SFC DWPTS AS
OF 19Z WERE STILL MOSTLY IN THE 5-10F RANGE ALONG THE MI/WI
BORDER...INDICATING THE DRYNESS THAT IS STILL AT THE SFC...AND
LATEST RAP FCST SOUNDINGS SHOW THE DRY AIR IN THE LOWER LEVELS
HANGING ON DURING THE EVENING. LATER TONIGHT INTO WED...FOCUS SHIFTS
TO THE AFORMENTIONED SHORTWAVES. THE STRONGER NRN WAVE WILL REACH
NRN ONTARIO EARLY WED MORNING WHILE THE WEAKER SRN WAVES WILL TRACK
INTO THE UPPER LAKES. TRACK OF THE STRONGER NRN WAVE INDICATES ITS
MAIN FORCING WILL PASS N OF HERE...AND THAT IS WHAT MODELS SHOW FOR
PROGRESSION OF DEEP LAYER QVECTORS. FARTHER S...THE WEAKER SRN WAVES
WILL BE ABLE TO INTERACT WITH THE SFC-850MB WARM FRONT AND
CONSIDERABLY MORE GENEROUS MOISTURE AS WELL AS ABUNDANT INSTABILITY.
LEAD SUBTLE WAVE IS ALREADY GENERATING AN EXPANDING AREA OF
SHRA/TSRA IN SRN MN/NW IA ON THE MUCAPE GRADIENT PER LATEST SPC
MESOANALYSIS. THRU WED MORNING...MODELS SHOW 850MB WARM FRONT NEVER
LIFTING ANY FARTHER N THAN SRN WI. BELIEVE THOSE MODEL SOLUTIONS
WHICH SHOW THE MAIN AREA OF PCPN PASSING S OF UPPER MI TONIGHT/WED
MORNING CLOSER TO 850MB WARM FRONT OR EVEN SFC FRONT ARE PROBABLY ON
THE RIGHT TRACK. THIS WOULD BE ESPECIALLY TRUE IF SIGNIFICANT
CONVECTION ENDS UP DEVELOPING/EXPANDING NEAR THE WARM FRONT...A
DEFINITE POSSIBILITY GIVEN THE MAGNITUDE OF INSTABILITY THAT WILL
REMAIN MUCH FARTHER S. WHILE THE SHRA/TSRA MOVING ACROSS SRN MN INTO
SW WI IS A CONCERN...THAT PCPN SHOULD TEND TO PEEL MORE EASTWARD
WITH TIME AS THE SHRA/TSRA SHOULDN`T BREAK TOO FAR AWAY FROM THE
INSTABILITY GRADIENT WHICH WILL REMAIN WELL S OF HERE. SO...THE GFS
WHICH CARRIES 1/3RD TO 1/2 INCH OF PCPN INTO SCNTRL UPPER MI
CERTAINLY LOOKS LIKE AN OUTLIER COMPARED TO THE OTHER MODELS WHICH
ARE MUCH LIGHTER ON PCPN. NONETHELESS...TAIL END OF NRN SHORTWAVE
WILL PROVIDE SUPPORT FOR AN EXTENSION OF PCPN N AND NW FROM HEAVIER
PCPN TO THE S. UTILIZING A CONSENSUS APPROACH FOR POPS...WEIGHTED
TOWARD HIGH RES GUIDANCE...WILL SPREAD A BAND OF CHC POPS ACROSS THE
AREA OVERNIGHT/WED MORNING WITH TREND TOWARD LOWER POPS OVER THE
NRN/ERN FCST AREA. WILL INCLUDE LIKELY POPS INTO MENOMINEE COUNTY.
PCPN WILL END (OR DIMINISH TO DZ BEFORE ENDING) FROM SW TO NE MID
MORNING THRU EARLY AFTN.
PTYPE IS A CHALLENGE. INITIAL DRY AIR MASS/EVAPORATIVE COOLING
SHOULD MAKE SNOW THE MORE DOMINANT PTYPE. HOWEVER...PERUSAL OF MODEL
FCST SOUNDINGS SHOW TEMP PROFILE HOVERING AROUND 0C OVER A FAIRLY
SIGNIFICANT DEPTH...INDICATING A VARIETY OF PTYPES WILL BE POSSIBLE
WITH ONLY VERY SLIGHT CHANGES TO THE TEMP PROFILE. SO...FCST WILL
REFLECT A WINTRY MIX OF SN/IP/FZRA/RA AT MOST LOCATIONS...THOUGH
MAINLY SN IS MORE LIKELY IN HIGHER TERRAIN AREAS. FOR PCPN
AMOUNTS...EXPECT TOTAL WATER EQUIVALENT PCPN OF ROUGHLY 0.05 TO 0.15
INCHES....GREATEST SCNTRL. SNOW AMOUNTS SHOULD BE UNDER 1 INCH...AND
WHERE FRZA OCCURS...A COUPLE OF HUNDREDTHS ARE POSSIBLE. AT THIS
POINT...ADVY HEADLINES ARE NOT WARRANTED. IF FOR SOME REASON TRENDS
THIS EVENING POINT TOWARD HEAVIER PCPN REACHING THE AREA...HEADLINES
WILL NEED TO BE RECONSIDERED.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 414 PM EDT TUE APR 7 2015
...AREAS OF FREEZING RAIN/ICING WED NIGHT INTO THU MORNING AND
POSSIBLE HEAVY SNOW THU NIGHT...
LARGE SCALE UPPER LEVEL PATTERN TO START THE LONG TERM FEATURES
TROUGHING FM CENTRAL CANADA SOUTHWEST ACROSS MUCH OF THE WESTERN
CONUS. MAIN SHORTWAVES WITHIN THE TROUGH ON WEDNESDAY NIGHT WILL BE
DIVING SOUTHEAST ACROSS MANITOBA AND STREAMING EASTWARD NEAR THE
FOUR CORNERS REGION. MAIN JET STREAKS WITHIN THE FLOW PATTERN ARE
ORIENTED FM GREAT LAKES TO NEW ENGLAND AND PUSHING ACROSS NORTHERN
MEXICO. AT THE SFC...MAIN CYCLONE IS VCNTY OF CNTRL PLAINS WITH WARM
FRONT EAST ACROSS THE OHIO VALLEY...LIFTING NORTHWARD.
WEAKER LEAD SHORTWAVE/INCREASING DIVERGENCE IN RRQ OF GREAT LAKES
JET/WARM AIR ADVECTION COMBINE TO BRING SOME PRECIP IN THE FORM OF
RAIN SHOWERS OVER THE REGION WEDNESDAY NIGHT INTO THURSDAY MORNING.
GFS/ECMWF/GEM-NH QUICKER IN BRINGING PRECIP OVER AREA...MORE 06Z-12Z
THURSDAY. NAM IS DELAYED...FAVORING 12Z-18Z ON THURSDAY. EITHER WAY
THINK BEST FOCUS FOR RAIN WILL BE ON NOSE OF VEERING H85 JET MAINLY
IMPACTING SOUTH AND EAST CWA. TSRA THAT COULD BE ONGOING ALONG WARM
FRONT COULD FURTHER DISRUPT MOISTURE TRANSPORT INTO UPPER GREAT
LAKES. DUE TO THESE REASONS...LIKE THE IDEA OF LESS QPF SINCE LARGER
SCALE FORCING OVER UPR MICHIGAN IS GENERALLY WEAK. SOUNDINGS AHEAD
OF ANY POTENTIAL PRECIP INDICATE LOW-LEVEL MOISTURE TO H9 BUT DRY
AIR ABOVE THROUGH H5 MUCH OF WEDNESDAY EVENING. SFC WINDS FM EAST
BTWN HIGH PRESSURE RIDGE OVER EASTERN CANADA AND LOW PRESSURE
LIFTING NORTHEAST OVER THE CNTRL PLAINS SUPPORTS BEST CHANCE OF
DZ/FZDZ GENERATED BY UPSLOPE LIFTING OVER HIGHER TERRAIN OF CNTRL
CWA FM MICHIGAMME HIGHLANDS IN BARAGA AND MARQUETTE COUNTY SOUTHWEST
TO MUCH OF IRON AND DICKINSON COUNTIES. EITHER FM THE FZDZ OR
EVENTUALLY ARRIVAL OF LIGHT FZRA...LIGHT ICING IS LIKELY ON
WEDNESDAY NIGHT AS TEMPS WILL STAY AT OR BLO FREEZING MOST OF THE
NIGHT. MAIN CONCERN WOULD BE ON UNTREATED ROADS AND SIDEWALKS BUT
THERE COULD ALSO BE SOME ICING THAT WOULD IMPACT ELEVATED OBJECTS
SUCH AS TREES AND POWERLINES. BEST SHOT OF MOST ICING WILL BE OVER
THE HIGHER TERRAIN AREAS FM BARAGA AND MARQUETTE COUNTY TO IRON AND
DICKINSON COUNTY. DID NOT GET TOO SPECIFIC BTWN DZ/FZDZ AND
RAIN/FZRA. SINCE EVEN IN THE DRIER SCENARIO THERE WOULD BE
MEASURABLE QPF...WENT WITH RAIN/FZRA. WILL KEEP MENTION OF THIS IN
HWO/EHWO...BUT NO HEADLINE ISSUED NOW AS AT THIS POINT SEEMS THAT AT
WORST COULD NEED AN ADVY.
BRIEF LULL POSSIBLE LATER THURSDAY MORNING INTO THURSDAY AFTERNOON
IN BETWEEN SHORTWAVES...LEAD ONE LIFTING ACROSS EASTERN ONTARIO AND
A MUCH STRONGER ONE...EDGING EASTWARD ACROSS CNTRL PLAINS...SET TO
ARRIVE OVER UPR GREAT LAKES THURSDAY NIGHT. SOUNDINGS FOR LATER
THURSDAY INDICATE SOME MOISTURE MAY STICK AROUND ON NORTHERN EDGE OF
SFC LOW LIFTING NORTHEAST FROM THE CNTRL MISSISSIPPI RIVER VALLEY
TOWARD THE WESTERN GREAT LAKES...BUT SEEMS THAT NET FORCING FOR
ANY PRECIP WILL BE MINIMAL. NORTHERN EDGE OF HIGHER MLCAPE AND
INTERSECTION OF LOW-LEVEL AND UPPER LEVEL JET AND H85 THETA-E
AXIS/MAX WARM AIR ADVECTION WOULD KEEP POTENTIAL FOR TSRA STAYING
WELL TO THE SOUTHEAST OF UPR MICHIGAN...LIKELY OVER LOWER GREAT
LAKES OR OHIO VALLEY DEPENDING ON LOCATION OF EMBEDDED WEAKER
CONVECTIVELY DRIVEN SHORTWAVES IN THE WSW FLOW ALOFT. GENERALLY
QUIET WEATHER SHOULD PREVAIL OVER UPPER LAKES THURSDAY AFTN UNTIL
MAIN SHORTWAVE ARRIVES ON THURSDAY NIGHT. MOISTURE ADVECTION INTO
THE AREA MAY CONTINUE TO SPUR ON SOME SHOWERS OR PATCHY RAIN...SO
KEPT CHANCES GOING THROUGH THE PERIOD DESPITE THE MINIMAL FORCING.
MODEL DIFFERENCES WITH STRENGTH AND WESTWARD EXTENT OF THURSDAY
NIGHT SHORTWAVE IS THE MAIN ISSUE ON INTO FRIDAY MORNING. OVERALL...
RECENT NAM/GEM-NH RUNS WERE FARTHER WEST WITH UPPER WAVE AND SFC
LOW WHILE THE 00Z ECMWF WAS MUCH FASTER WITH EASTWARD PUSH OF THE
SHORTWAVE/SFC LOW AND COLD FRONT. GFS REPRESENTED A COMPROMISE
SOLUTION. BY FAR...00Z AND 12Z ECMWF ARE DRIEST...INDICATING LESS
THAN 0.25 INCH OF QPF FM 00Z FRIDAY TO 12Z FRIDAY. MEANWHILE...
NAM/GFS/GEM-NH SHOWED QPF AMOUNTS AT LEAST UP TO 1 INCH...SO QUITE
THE DIFFERENCE.
12Z NAM TRENDED MORE LIKE THE GFS IN TERMS OF LOCATION OF SFC LOW FM
00Z FRIDAY TO 12Z FRIDAY. IN TERMS OF QPF...NAM TRENDED AWAY FM
STRIPE OF 1.5 INCH PLUS AMOUNTS IT WAS SHOWING BUT STILL HAS UP TO
1.25 INCHES OVER PARTS OF WESTERN UPR MICHIGAN. IN FACT...IN THE
VCNTY OF KIWD IS HAS TRENDED MUCH WETTER AS 00Z RUN SHOWED LESS THAN
0.10 INCH...BUT 12Z RUN NOW HAS ALMOST 0.75 INCHES. GUESSING THIS IS
DUE TO MORE PHASING OCCURRING BTWN SHORTWAVE CROSSING THE UPPER
LAKES AND THE APPROACHING WAVE DRIVING SOUTHEAST OVER MANITOBA AND
NORTHERN ONTARIO WHICH IN TURN INCREASES RIGHT ENTRANCE JET STREAK
DIVERGENCE AND ASSOCIATED MID-LEVEL FGEN. 12Z GFS SIMILAR TO
PREVIOUS RUNS WITH SFC LOW POSITION...BUT NOW FOCUSES QPF MORE OVER
WESTERN CWA. GFS SHOWS NOT ONLY MAIN SHORTWAVE LIFTING OVER UPPER
GREAT LAKES AND WAVE OVER NORTHERN ONTARIO...BUT ALSO ANOTHER WAVE
TRYING TO SNEAK IN FM NORTHERN PLAINS. SCENARIO JUST BECOMES MORE
COMPLICATED YET. PTYPE WITH MOST OF THE PRECIP WOULD BE RAIN
CHANGING TO SNOW. POSSIBLE FZRA AS WELL AS ADVECTION OF COLDER LOW-
LEVEL AIRMASS UNDERCUTS LINGERING WARM LAYER ALOFT AT H8-H75. SIGNAL
FOCUSING THAT FAR WEST VCNTY OF KIWD COULD SEE HEAVY SNOW THURSDAY
EVENING INTO THE EARLY MORNING OF FRIDAY DUE TO QUICKER CHANGE FM
RAIN TO SNOW AND GREATER POTENTIAL FOR HEAVIER QPF. WILL CONTINUE TO
MENTION THIS IN THE HWO/EHWO BUT NOT HIT IT UP MUCH HARDER JUST YET
AS UNCERTAINTY REMAINS SINCE THE TYPICALLY BETTER PERFORMING ECMWF
HAS BEEN CONSISTENTLY NOT NEAR AS BULLISH WITH THE SYSTEM AS OTHER
MODELS. AND ITS REALLY NOT EVEN CLOSE.
LOW PRESSURE SYSTEM EXITS ACROSS EASTERN CANADA ON FRIDAY. LINGERING
AIRMASS IS COOL THOUGH AS LOWERED TEMPS WITH THERMAL TROUGH AT H85
REMAINING OVER THE AREA. SHOULD STAY MOSTLY CLOUDY EVEN FARTHER
INLAND WITH POSSIBLE INSTABILITY RAIN/SNOW SHOWERS SINCE THE THERMAL
TROUGH STAYS IN THE VCNTY. HIGH PRESSURE SLIDES OVERHEAD TO START
THE WEEKEND SO LOOKING FOR DRY AND MUCH WARMER CONDITIONS ON
SATURDAY. WINDS BECOME SOUTHWEST AS RIDGE PASSES SATURDAY AFTN.
MIXING TO H9 WOULD SUPPORT HIGHS WELL INTO THE 50S OVER MOST CWA. BY
LATE WEEKEND...UPPER PATTERN SHOWS LARGER TROUGH OVER WESTERN CANADA
AND NORTHWEST CONUS...WITH MORE COMPACT UPPER LOW TRACKING OVER THE
SOUTHWEST CONUS. THERE IS A LOT OF UNCERTAINTY IN HOW THAT SOUTHERN
STREAM WAVE EVOLVES. PREVIOUS ECMWF SHOWED A WRAPPED UP SFC LOW OVER
THE CNTRL PLAINS...WHILE THE 12Z ECMWF SHOWS NOTHING OF THE SORT.
ESSENTIALLY...SEE NO REASON TO STRAY FM CONSENSUS BEYOND THE LATE
WEEK SYSTEM GIVEN THE BIGGER UNCERTAINTY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 135 PM EDT TUE APR 7 2015
A STEADY ENE WIND ON THE SRN FLANK OF HIGH PRES RIDGE EXTENDING
ACROSS NRN ONTARIO WILL CONTINUE TO ADVECT LOW-LEVEL DRY AIR INTO
UPPER MI THRU THIS EVENING...RESULTING IN VFR CONDITIONS AT
KIWD/KCMX/KSAW DESPITE CONSIDERABLE MID CLOUDS. AS A DISTURBANCE
MOVES INTO THE GREAT LAKES TONIGHT...LIGHT PCPN WILL PROBABLY AFFECT
ALL TERMINALS LATE TONIGHT INTO WED MORNING. ALONG WITH -SN...THERE
MAY BE SOME -RA/-FZRA...THOUGH CONFIDENCE IS QUITE LOW ON PTYPE.
EXPECT MVFR CONDITIONS TO EVENTUALLY DEVELOP...AND LINGER THRU THE
END OF THE FCST PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 448 PM EDT TUE APR 7 2015
WITH LAKE SUPERIOR SITUATED BETWEEN HIGH PRES THAT WILL MOVE
FROM NRN ONTARIO INTO QUEBEC THRU WED AND A WARM FRONT THAT
WILL REMAIN TO THE S AND SW ACROSS THE PLAINS TO OHIO VALLEY...E TO
NE WINDS WILL PERSIST. TYPICAL FOR E TO NE WINDS...WINDS WILL BE
STRONGEST OVER WRN LAKE SUPERIOR...IN PARTICULAR BTWN THE APOSTLE
ISLANDS AND MN NSHORE WHERE FUNNELING/COASTAL CONVERGENCE ENHANCE
THE WINDS. IN THAT AREA...EXPECT NE WINDS OF 20-30KT TONIGHT...WITH
SOME GALE FORCE GUSTS TO AROUND 35 KT THRU THE EVENING. E TO NE
WINDS...MOSTLY 10-20KT...WILL THEN CONTINUE ON WED AND ON INTO THU
AS LOW PRES LIFTS NE FROM THE CENTRAL PLAINS INTO THE GREAT LAKES
REGION. AT THIS TIME...IT APPEARS THE LOW WILL NOT BE STRONG ENOUGH
TO RESULT IN GALES AS THE LOW APPROACHES AND THEN DEPARTS. WINDS
WILL BACK TO THE N THU AND THEN NW 20-30KT THU NIGHT INTO FRI AS THE
LOW SHIFTS TO THE E AND HIGH PRES BUILDS INTO THE PLAINS. A PERIOD
OF LIGHT WINDS WILL OCCUR FRI NIGHT INTO SAT AS HIGH PRES RIDGE
MOVES ACROSS THE UPPER LAKES. S WINDS WILL THEN BE ON THE INCREASE
TO AT LEAST 10-20KT ON SUN AS THE RIDGE SHIFTS E AND A LOW PRES TROF
MOVES E TO THE UPPER MISSISSIPPI VALLEY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
415 PM EDT TUE APR 7 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 421 AM EDT TUE APR 7 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR MI UNDER A
CONFLUENT WNW FLOW ALOFT BTWN ARCTIC BRANCH CLOSED LO OVER NRN
QUEBEC AND SRN BRANCH RDG IN THE PLAINS DOWNSTREAM OF TROF ALONG THE
W COAST. UPR MI REMAINS IN THE RRQ OF 130KT H3 JET MAX WITHIN THE
CONFLUENCE ZN OF THESE TWO BRANCHES. WV IMAGERY AND RUC ANALYSIS
ALSO INDICATE A SHRTWV OVER NDAKOTA THAT IS SLIDING TO THE E. THE
DPVA/MID LVL QVECTOR CNVGC AHEAD OF THIS SHRTWV AND SOME UPR
DVGC/MID LVL FGEN IN THE RRQ OF THE UPR JET ARE AIDING A LINE OF
LIGHT SN/MIXED PCPN ACRS NCENTRAL WI INTO FAR SRN MNM COUNTY WELL TO
THE N OF FAIRLY SHARP H85 WARM FNT ORIENTED W-E ACRS THE LOWER LKS.
HOWEVER...THE NNE LLVL FLOW OF VERY DRY AIR SHOWN ON THE 00Z INL
RAOB TO THE S OF HI PRES STRETCHING FM NEAR LK WINNIPEG ACROSS NW
ONTARIO AND INTO QUEBEC IS PREVENTING THIS PCPN FM MOVING FARTHER TO
THE N. BUT THERE ARE PLENTY OF MID/HI CLDS OVER THE CWA...THICKEST
OVER THE SRN TIER. LOOKING FARTHER UPSTREAM...ANOTHER SHRTWV IS
LIFTING TOWARD THE NRN PLAINS IN THE SW FLOW ALOFT BTWN THE PLAINS
RDG AND THE TROF ALONG THE W COAST.
MAIN FCST CONCERNS THRU TNGT WL BE POPS ALONG THE WI BORDER EARLY
THIS FCST PERIOD IN ASSOCIATION WITH THE SHRTWV NOW APRCH MN. FOCUS
FOR TNGT WL BE ON IMPACT OF SECOND DISTURBANCE APRCHG THE NRN PLAINS
AND ANOTHER DISTURBANCE THE MODELS SHOW WL MOVE THRU WI.
TDAY...FIRST SHRTWV OVER NW MN IS FCT TO DRIFT TO THE E AND INTO RRQ
OF UPR STREAK TO THE E...ACCOMPANIED BY AN AREA OF DEEP LYR QVECTOR
CNVGC. ALTHOUGH THIS SETUP WOULD NORMALLY SUPPORT WDSPRD PCPN...ALL
THE MODELS SHOW A STEADY FEED OF SFC-H85 DRY AIR FM THE NE THRU THE
DAY. IN FACT...AFTER LINGERING PCPN ENDS EARLY THIS MRNG OVER FAR
SRN MENOMINEE COUNTY...ALL OF THE MODELS SHOW NO PCPN OVER UPR MI
THRU 00Z THIS EVNG. BUT WITH CONSIDERABLE MID/HI CLD ABOVE THE LLVL
DRY AIR AND AN ENE WIND OFF THE CHILLY LK WATERS...MAX TEMPS THIS
AFTN SHOULD RUN BLO NORMAL. EXPECT READINGS TO REACH THE LO 40S AWAY
FM THE LKS...WHERE TEMPS WL HOLD IN THE 30S.
TNGT...AS THE CONFLUENCE ZN SHIFTS SLOWLY TO THE NE TDAY...SHRTWV
NOW TRACKING INTO THE NRN PLAINS IS FCST TO LIFT NE INTO SCENTRAL
CANADA...WITH BULK OF DEEP LYR QVECTOR CNVGC PASSING TO THE NW. BUT
GENERAL MODEL CONSENSUS ALSO HINTS ANOTHER SHRTWV EMERGING FM THE
WRN TROF AND THRU THE PLAINS TDAY WL DRIFT INTO WI LATE TNGT...
ACCOMPANIED BY AREA OF FAIRLY SHARP UPR DVGC EVEN AS THE MAIN UPR
JET CORE TO THE E SLIPS FARTHER AWAY ALONG WITH THE UPR CONFLUENCE
ZN. MOST OF THE MODELS FOCUS SOMEWHAT HIER QPF OVER THE SCNTRL
CWA...CLOSER TO WHERE THE CORE OF UPR DVGC/AXIS OF SHARPEST MID LVL
FGEN TO THE N OF H85 WARM FNT THAT IS FCST TO LIFT NWD WITH THE APRCH
OF THIS DISTURBANCE. DESPITE THE GENERAL AGREEMENT ON THESE
FEATURES...MODEL QPF AND FCST THERMAL FIELDS ARE QUITE VARIABLE. THE
GFS IS WETTEST OVERALL...SHOWING AS MUCH AS 0.25-0.35 INCH OVER THE
SCNTRL CLOSER TO THE SHARPER FORCING/FGEN AND WHERE THIS MODEL SHOWS
H7 SPECIFIC HUMIDITY IN THE 3-4 G/KG RANGE. BUT MANY OF THE HIER RES
MODELS...LIKE THE 00Z NAM AND REGIONAL CNDN...SHOW LTL IF ANY PCPN
EVEN THERE. GIVEN PERSISTENCE OF LLVL DRY AIR OVER THE NE CWA AND THE
WEAKENING OF THE FORCING WITH TIME AS THE DISTURBANCE LIFTS TO THE
NE...WL TEND TO KEEP THE NE CWA DRIER LONGER. PTYPE WL BE A
CONCERN...AND MODEL DIFFERENCES COMPOUND THE UNCERTAINTY. SINCE THE
GFS SHOWS MORE VERTICAL MOTION/QPF AND THUS MORE DYNAMIC/EVAPORATIVE
COOLING...THAT MODEL FCST SDNGS INDICATE A MAINLY SN EVENT...WITH SN
AMOUNTS OVER THE SCENTRAL AT LEAST APRCHG ADVY CRITERIA. CONSIDERING
THE WIDE DIFFERENCES IN QPF/IMPACT OF LINGERING DRY AIR...DID NOT
CONSIDER AN ADVY ATTM EVEN THOUGH TRACK OF DISTURBANCE TO THE S AND
VERY DRY NATURE OF THE ANTECEDENT AIRMASS WOULD FAVOR MAINLY SN. MANY
OF THE OTHER MODELS SHOW AN ELEVATED WARM LYR WITH MAX TEMPS ALOFT
OVER 0C. WITH LLVL DRY AIR THAT WL ALLOW FOR MORE NEAR SFC
COOLING...FREEZING RA AND PERHAPS SLEET...ESPECIALLY NEAR THE ONSET
OF THE PCPN WHEN THE LLVLS ARE DRIER AND WBLB TEMPS LO ENUF TO ALLOW
FOR A BETTER CHC FOR THE DROPS TO FREEZE INTO ICE PELLETS...ARE
POSSIBLE. SO RETAINED A MENTION OF THESE PTYPES.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 414 PM EDT TUE APR 7 2015
...AREAS OF FREEZING RAIN/ICING WED NIGHT INTO THU MORNING AND
POSSIBLE HEAVY SNOW THU NIGHT...
LARGE SCALE UPPER LEVEL PATTERN TO START THE LONG TERM FEATURES
TROUGHING FM CENTRAL CANADA SOUTHWEST ACROSS MUCH OF THE WESTERN
CONUS. MAIN SHORTWAVES WITHIN THE TROUGH ON WEDNESDAY NIGHT WILL BE
DIVING SOUTHEAST ACROSS MANITOBA AND STREAMING EASTWARD NEAR THE
FOUR CORNERS REGION. MAIN JET STREAKS WITHIN THE FLOW PATTERN ARE
ORIENTED FM GREAT LAKES TO NEW ENGLAND AND PUSHING ACROSS NORTHERN
MEXICO. AT THE SFC...MAIN CYCLONE IS VCNTY OF CNTRL PLAINS WITH WARM
FRONT EAST ACROSS THE OHIO VALLEY...LIFTING NORTHWARD.
WEAKER LEAD SHORTWAVE/INCREASING DIVERGENCE IN RRQ OF GREAT LAKES
JET/WARM AIR ADVECTION COMBINE TO BRING SOME PRECIP IN THE FORM OF
RAIN SHOWERS OVER THE REGION WEDNESDAY NIGHT INTO THURSDAY MORNING.
GFS/ECMWF/GEM-NH QUICKER IN BRINGING PRECIP OVER AREA...MORE 06Z-12Z
THURSDAY. NAM IS DELAYED...FAVORING 12Z-18Z ON THURSDAY. EITHER WAY
THINK BEST FOCUS FOR RAIN WILL BE ON NOSE OF VEERING H85 JET MAINLY
IMPACTING SOUTH AND EAST CWA. TSRA THAT COULD BE ONGOING ALONG WARM
FRONT COULD FURTHER DISRUPT MOISTURE TRANSPORT INTO UPPER GREAT
LAKES. DUE TO THESE REASONS...LIKE THE IDEA OF LESS QPF SINCE LARGER
SCALE FORCING OVER UPR MICHIGAN IS GENERALLY WEAK. SOUNDINGS AHEAD
OF ANY POTENTIAL PRECIP INDICATE LOW-LEVEL MOISTURE TO H9 BUT DRY
AIR ABOVE THROUGH H5 MUCH OF WEDNESDAY EVENING. SFC WINDS FM EAST
BTWN HIGH PRESSURE RIDGE OVER EASTERN CANADA AND LOW PRESSURE
LIFTING NORTHEAST OVER THE CNTRL PLAINS SUPPORTS BEST CHANCE OF
DZ/FZDZ GENERATED BY UPSLOPE LIFTING OVER HIGHER TERRAIN OF CNTRL
CWA FM MICHIGAMME HIGHLANDS IN BARAGA AND MARQUETTE COUNTY SOUTHWEST
TO MUCH OF IRON AND DICKINSON COUNTIES. EITHER FM THE FZDZ OR
EVENTUALLY ARRIVAL OF LIGHT FZRA...LIGHT ICING IS LIKELY ON
WEDNESDAY NIGHT AS TEMPS WILL STAY AT OR BLO FREEZING MOST OF THE
NIGHT. MAIN CONCERN WOULD BE ON UNTREATED ROADS AND SIDEWALKS BUT
THERE COULD ALSO BE SOME ICING THAT WOULD IMPACT ELEVATED OBJECTS
SUCH AS TREES AND POWERLINES. BEST SHOT OF MOST ICING WILL BE OVER
THE HIGHER TERRAIN AREAS FM BARAGA AND MARQUETTE COUNTY TO IRON AND
DICKINSON COUNTY. DID NOT GET TOO SPECIFIC BTWN DZ/FZDZ AND
RAIN/FZRA. SINCE EVEN IN THE DRIER SCENARIO THERE WOULD BE
MEASURABLE QPF...WENT WITH RAIN/FZRA. WILL KEEP MENTION OF THIS IN
HWO/EHWO...BUT NO HEADLINE ISSUED NOW AS AT THIS POINT SEEMS THAT AT
WORST COULD NEED AN ADVY.
BRIEF LULL POSSIBLE LATER THURSDAY MORNING INTO THURSDAY AFTERNOON
IN BETWEEN SHORTWAVES...LEAD ONE LIFTING ACROSS EASTERN ONTARIO AND
A MUCH STRONGER ONE...EDGING EASTWARD ACROSS CNTRL PLAINS...SET TO
ARRIVE OVER UPR GREAT LAKES THURSDAY NIGHT. SOUNDINGS FOR LATER
THURSDAY INDICATE SOME MOISTURE MAY STICK AROUND ON NORTHERN EDGE OF
SFC LOW LIFTING NORTHEAST FROM THE CNTRL MISSISSIPPI RIVER VALLEY
TOWARD THE WESTERN GREAT LAKES...BUT SEEMS THAT NET FORCING FOR
ANY PRECIP WILL BE MINIMAL. NORTHERN EDGE OF HIGHER MLCAPE AND
INTERSECTION OF LOW-LEVEL AND UPPER LEVEL JET AND H85 THETA-E
AXIS/MAX WARM AIR ADVECTION WOULD KEEP POTENTIAL FOR TSRA STAYING
WELL TO THE SOUTHEAST OF UPR MICHIGAN...LIKELY OVER LOWER GREAT
LAKES OR OHIO VALLEY DEPENDING ON LOCATION OF EMBEDDED WEAKER
CONVECTIVELY DRIVEN SHORTWAVES IN THE WSW FLOW ALOFT. GENERALLY
QUIET WEATHER SHOULD PREVAIL OVER UPPER LAKES THURSDAY AFTN UNTIL
MAIN SHORTWAVE ARRIVES ON THURSDAY NIGHT. MOISTURE ADVECTION INTO
THE AREA MAY CONTINUE TO SPUR ON SOME SHOWERS OR PATCHY RAIN...SO
KEPT CHANCES GOING THROUGH THE PERIOD DESPITE THE MINIMAL FORCING.
MODEL DIFFERENCES WITH STRENGTH AND WESTWARD EXTENT OF THURSDAY
NIGHT SHORTWAVE IS THE MAIN ISSUE ON INTO FRIDAY MORNING. OVERALL...
RECENT NAM/GEM-NH RUNS WERE FARTHER WEST WITH UPPER WAVE AND SFC
LOW WHILE THE 00Z ECMWF WAS MUCH FASTER WITH EASTWARD PUSH OF THE
SHORTWAVE/SFC LOW AND COLD FRONT. GFS REPRESENTED A COMPROMISE
SOLUTION. BY FAR...00Z AND 12Z ECMWF ARE DRIEST...INDICATING LESS
THAN 0.25 INCH OF QPF FM 00Z FRIDAY TO 12Z FRIDAY. MEANWHILE...
NAM/GFS/GEM-NH SHOWED QPF AMOUNTS AT LEAST UP TO 1 INCH...SO QUITE
THE DIFFERENCE.
12Z NAM TRENDED MORE LIKE THE GFS IN TERMS OF LOCATION OF SFC LOW FM
00Z FRIDAY TO 12Z FRIDAY. IN TERMS OF QPF...NAM TRENDED AWAY FM
STRIPE OF 1.5 INCH PLUS AMOUNTS IT WAS SHOWING BUT STILL HAS UP TO
1.25 INCHES OVER PARTS OF WESTERN UPR MICHIGAN. IN FACT...IN THE
VCNTY OF KIWD IS HAS TRENDED MUCH WETTER AS 00Z RUN SHOWED LESS THAN
0.10 INCH...BUT 12Z RUN NOW HAS ALMOST 0.75 INCHES. GUESSING THIS IS
DUE TO MORE PHASING OCCURRING BTWN SHORTWAVE CROSSING THE UPPER
LAKES AND THE APPROACHING WAVE DRIVING SOUTHEAST OVER MANITOBA AND
NORTHERN ONTARIO WHICH IN TURN INCREASES RIGHT ENTRANCE JET STREAK
DIVERGENCE AND ASSOCIATED MID-LEVEL FGEN. 12Z GFS SIMILAR TO
PREVIOUS RUNS WITH SFC LOW POSITION...BUT NOW FOCUSES QPF MORE OVER
WESTERN CWA. GFS SHOWS NOT ONLY MAIN SHORTWAVE LIFTING OVER UPPER
GREAT LAKES AND WAVE OVER NORTHERN ONTARIO...BUT ALSO ANOTHER WAVE
TRYING TO SNEAK IN FM NORTHERN PLAINS. SCENARIO JUST BECOMES MORE
COMPLICATED YET. PTYPE WITH MOST OF THE PRECIP WOULD BE RAIN
CHANGING TO SNOW. POSSIBLE FZRA AS WELL AS ADVECTION OF COLDER LOW-
LEVEL AIRMASS UNDERCUTS LINGERING WARM LAYER ALOFT AT H8-H75. SIGNAL
FOCUSING THAT FAR WEST VCNTY OF KIWD COULD SEE HEAVY SNOW THURSDAY
EVENING INTO THE EARLY MORNING OF FRIDAY DUE TO QUICKER CHANGE FM
RAIN TO SNOW AND GREATER POTENTIAL FOR HEAVIER QPF. WILL CONTINUE TO
MENTION THIS IN THE HWO/EHWO BUT NOT HIT IT UP MUCH HARDER JUST YET
AS UNCERTAINTY REMAINS SINCE THE TYPICALLY BETTER PERFORMING ECMWF
HAS BEEN CONSISTENTLY NOT NEAR AS BULLISH WITH THE SYSTEM AS OTHER
MODELS. AND ITS REALLY NOT EVEN CLOSE.
LOW PRESSURE SYSTEM EXITS ACROSS EASTERN CANADA ON FRIDAY. LINGERING
AIRMASS IS COOL THOUGH AS LOWERED TEMPS WITH THERMAL TROUGH AT H85
REMAINING OVER THE AREA. SHOULD STAY MOSTLY CLOUDY EVEN FARTHER
INLAND WITH POSSIBLE INSTABILITY RAIN/SNOW SHOWERS SINCE THE THERMAL
TROUGH STAYS IN THE VCNTY. HIGH PRESSURE SLIDES OVERHEAD TO START
THE WEEKEND SO LOOKING FOR DRY AND MUCH WARMER CONDITIONS ON
SATURDAY. WINDS BECOME SOUTHWEST AS RIDGE PASSES SATURDAY AFTN.
MIXING TO H9 WOULD SUPPORT HIGHS WELL INTO THE 50S OVER MOST CWA. BY
LATE WEEKEND...UPPER PATTERN SHOWS LARGER TROUGH OVER WESTERN CANADA
AND NORTHWEST CONUS...WITH MORE COMPACT UPPER LOW TRACKING OVER THE
SOUTHWEST CONUS. THERE IS A LOT OF UNCERTAINTY IN HOW THAT SOUTHERN
STREAM WAVE EVOLVES. PREVIOUS ECMWF SHOWED A WRAPPED UP SFC LOW OVER
THE CNTRL PLAINS...WHILE THE 12Z ECMWF SHOWS NOTHING OF THE SORT.
ESSENTIALLY...SEE NO REASON TO STRAY FM CONSENSUS BEYOND THE LATE
WEEK SYSTEM GIVEN THE BIGGER UNCERTAINTY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 135 PM EDT TUE APR 7 2015
A STEADY ENE WIND ON THE SRN FLANK OF HIGH PRES RIDGE EXTENDING
ACROSS NRN ONTARIO WILL CONTINUE TO ADVECT LOW-LEVEL DRY AIR INTO
UPPER MI THRU THIS EVENING...RESULTING IN VFR CONDITIONS AT
KIWD/KCMX/KSAW DESPITE CONSIDERABLE MID CLOUDS. AS A DISTURBANCE
MOVES INTO THE GREAT LAKES TONIGHT...LIGHT PCPN WILL PROBABLY AFFECT
ALL TERMINALS LATE TONIGHT INTO WED MORNING. ALONG WITH -SN...THERE
MAY BE SOME -RA/-FZRA...THOUGH CONFIDENCE IS QUITE LOW ON PTYPE.
EXPECT MVFR CONDITIONS TO EVENTUALLY DEVELOP...AND LINGER THRU THE
END OF THE FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 421 AM EDT TUE APR 7 2015
WITH LAKE SUPERIOR SITUATED BETWEEN HI PRES THAT WILL MOVE ACROSS NW
ONTARIO INTO QUEBEC THRU WED AND A WARM FRONT THAT WILL REMAIN TO
THE S AND SW ACROSS THE PLAINS TO OHIO VALLEY...E TO NE WINDS WILL
PERSIST. TYPICAL FOR E TO NE WINDS...WINDS WILL BE STRONGEST OVER
WRN LAKE SUPERIOR...IN PARTICULAR BTWN THE APOSTLE ISLANDS AND MN
NSHORE WHERE FUNNELING/COASTAL CONVERGENCE ENHANCE THE WINDS. IN
THAT AREA...15-25KT WINDS WILL INCREASE TO 20-30KT THIS MORNING INTO
THIS EVENING. E TO NE WINDS...MOSTLY 10-20KT...WILL THEN CONTINUE ON
WED AND ON INTO THU AS LO PRES LIFTS NE FROM THE CENTRAL PLAINS
TOWARD THE GREAT LAKES REGION. AT THIS TIME...NO GALES APPEAR
LIKELY. BUT WINDS WILL BACK TO THE N AND THEN NW UP TO 25 KTS THU
NIGHT INTO FRI ONCE THE LO SHIFTS TO THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...KC
ADDRESSED IN PREVIOUS FORECAST DISCUSSIONS. THE BIGGEST UNKNOWN IS
WHAT THE POTENTIAL FOR WET BULB COOLING WILL BE AS DEWPOINTS HAVE
BEEN FORECASTED TO BE AROUND THE 32 DEGREE MARK. THE IDEA THIS
PACKAGE IS TO FAVOR A WARMER SOLUTION GIVEN THE OVERALL AMOUNT OF
MIDLEVEL WARM AIR ADVECTION THAT IS EXPECTED TO OCCUR. MOS GUIDANCE
IS WARM WITH SURFACE TEMPERATURES AT BAD AXE WELL ABOVE THE FREEZING
MARK...AND ALSO WARM WITH SURFACE DEWPOINTS. WHILE IT REMAINS
POSSIBLE THAT ISOLATED LOCATIONS COULD SEE SOME LIGHT FREEZING RAIN
OCCUR ON ELEVATED SURFACES...THE BREADTH OF MODEL OUTPUT ALONG WITH
COLLABORATIVE CONCERNS
&&
.LONG TERM...WEDNESDAY THROUGH NEXT TUESDAY
THE LONG TERM FORECAST LOOKS TO START OFF QUITE WET AS AN ACTIVE
PATTERN REMAINS OVER THE GREAT LAKES THROUGH FRIDAY. TO START OFF
WEDNESDAY MORNING...A WEAK SURFACE LOW TRACKING ALONG A STATIONARY
FRONT WILL BRING SOME LIGHT RAINS SHOWERS TO SOUTHEAST MICHIGAN.
WHILE THERE IS A POTENTIAL FOR SOME THUNDER ASSOCIATED WITH THESE
SHOWERS /ESPECIALLY TOWARDS THE OHIO BORDER/ ...INSTABILITY IS
UNIMPRESSIVE FOR WEDNESDAY AND CONFIDENCE IS LOW THAT THUNDERSTORMS
WILL DEVELOP. OVERALL...CURRENT THINKING IS THAT WHILE CURRENT MODEL
RUNS SHOW RAIN PRETTY MUCH THROUGHOUT ALL OF WEDNESDAY... THE BEST
CHANCE FOR THESE SHOWERS WILL BE IN THE MORNING HOURS...WITH A BRIEF
DRY PERIOD OR AT LEAST RAIN BECOMING MORE SCATTERED IN THE AFTERNOON
AS SUBSIDENCE MAKES ITS WAY INTO THE REGION. HIGH TEMPERATURES WILL
BE FAIRLY COOL ON WEDNESDAY /MID TO UPPER 40S/ ACROSS THE REGION.
RAIN SHOWERS RETURN AS A STRONGER AND DEEPER LOW PRESSURE SYSTEM
TRACKS ACROSS MICHIGAN EARLY THURSDAY MORNING. THIS LOW WILL FORCE A
WARM FRONT INTO THE REGION...BRINGING A ROUND A RAIN SHOWERS AND
THUNDERSTORMS AFTER SUNRISE. WITH BETTER FORCING AND PLENTY OF
MOISTURE...CONFIDENCE IN THUNDERSTORM DEVELOPMENT IS HIGHER. MAIN
CONCERN WITH THIS SYSTEM IS ON THE TRACK AND HOW FAR NORTH THE WARM
FRONT CAN PUSH. THE FURTHER NORTH THE WARM FRONT CAN SLIDE...THE
FURTHER NORTH THE WARM AIR CAN ALSO FILTER. THIS WARM FRONT WILL
DETERMINE HOW HIGH OUR MAX TEMPS ON THURSDAY WILL GET...WHICH COULD
BE A DIFFERENCE OF NEARLY 15 DEGREES DEPENDING ON IF/WHEN/HOW FAR
THE FRONT SLIDES. FOR NOW...HAVE OPTED TO GO WITH THE FURTHER NORTH
TRACK AS MODELS ARE TRENDING ON MORE NORTHERLY ROUTE IN RECENT RUNS.
THIS WILL ALLOW TEMPS ON THURSDAY TO MAKE IT INTO THE UPPER 60S IN
THE SOUTHERN CWA AND ONLY IN THE MID 50S ACROSS THE SAGINAW VALLEY
AND NORTHERN THUMB. DEPENDING ON HOW FAR NORTH THE LOW TRACKS WE
COULD ALSO BE IMPACTED BY THE COLD FRONT WITH THE SYSTEM. THIS WOULD
BRING ANOTHER ROUND OF MORE INTENSE SHOWERS AND THUNDERSTORMS TO
SOUTHEAST MICHIGAN LATE THURSDAY AFTERNOON AND EVENING. FOR NOW HAVE
KEPT OUT ANY MENTION OF SEVERE WEATHER ON THURSDAY AFTERNOON AS THE
TRACK OF THE SYSTEM IS STILL UNCERTAIN...HOWEVER WILL HAVE TO KEEP
AN EYE ON THIS SYSTEM OVER THE NEXT DAY TO DETERMINE IF ANY SEVERE
WEATHER WILL BE ANTICIPATED.
FOR FRIDAY AND THE WEEKEND...RAIN SHOWERS WILL MOVE EASTWARD ON
FRIDAY MORNING...FOLLOWED BY SURFACE HIGH PRESSURE BUILDING INTO THE
AREA RESULTING IN A RETURN TO DRY WEATHER. THIS HIGH WILL STICK
AROUND THROUGH SUNDAY RESULTING IN NICE SPRINGTIME WEATHER /HIGHS IN
THE MID 50S TO LOW 60S AND PARTLY CLOUDY SKIES/. THE NEXT WEATHER
MAKER ARRIVES MONDAY...BUT THE TIMING IS VERY INCONSISTENT AMONG
MODELS AND THEREFORE ONLY FELT CONFIDENT PUTTING IN CHANCE POPS FOR
THE MONDAY THROUGH TUESDAY TIMEFRAME. HIGH TEMPS WILL REMAIN IN THE
UPPER 50S TO LOW 60S ON MONDAY AND TUESDAY.
&&
.MARINE...
STRONG GUSTY NORTHWEST WINDS WILL BEGIN TUESDAY NIGHT AND LAST
THROUGH WEDNESDAY. WINDS COULD REACH UP TO 25 KNOTS OVER LAKE HURON
DURING THIS TIMEFRAME WITH WAVES BUILDING OVER 4 FEET ACROSS THE
LAKE HURON NEARSHORE WATERS. THEREFORE... SMALL CRAFT ADVISORIES
REMAIN IN EFFECT UNTIL WEDNESDAY EVENING. IN ADDITION TO GUSTY
WINDS...RAIN WILL BE POSSIBLE TUESDAY NIGHT AND INTO WEDNESDAY AS A
WEAK LOW PRESSURE SYSTEM SLIDES ACROSS THE AREA. A BETTER CHANCE FOR
RAIN AS WELL AS THUNDERSTORMS WILL ARRIVE WEDNESDAY NIGHT AND INTO
THURSDAY AS A STRONGER LOW TRACKS ACROSS THE CENTRAL GREAT LAKES.
WIND GUSTS ARE EXPECTED TO INCREASE UP TO 30 KNOTS IN SOME LOCATIONS
WITH THIS SYSTEM. SMALL CRAFT ADVISORIES MAY BE NEEDED ONCE AGAIN
FOR THURSDAY NIGHT AND FRIDAY MORNING. HIGH PRESSURE...DRY
CONDITIONS...AND CALMER WINDS RETURN FOR FRIDAY AND INTO THE
WEEKEND.
&&
.AVIATION...ISSUED 215 PM EDT TUE APR 7 2015
QUASI-ZONAL FLOW WITH EMBEDDED...NOISY SHORTWAVE ENERGY ADVECTING
WITHIN IT CONTINUES TO BRING LOW CONFIDENCE IN SHOWER
TRENDS/TIMING OVER THE NEXT 6 HOURS. ARC OF SHOWERS CURRENTLY
LIFTING NORTHWARD OVER THE MICHIGAN/OHIO STATELINE IS OCCURING
ALONG THE LEAD EDGE OF RICHER MIDLEVEL THETA E CONTENT. MODEL DATA
SUGGESTS THIS WILL SLOWLY TRACK NORTH AND EAST THROUGH 00Z. HAVE
INCLUDED A TEMPO GROUPING FOR SHOWERS AND POSSIBLE IFR CIGS FOR
THE FIRST 3 HOURS OF THE TAF PERIOD. OTHERWISE...QUIET AVIATION
CONDITIONS ARE EXPECTED THIS EVENING AHEAD OF APPROACHING REMNANT
CONVECTIVE SYSTEM THAT WILL EXIT OUT OF PORTIONS OF IA/SOUTHERN
WI. TIMING OF THIS CONVECTIVE SYSTEM WILL BE AFTER 9Z FOR TAF
SITES ACROSS SOUTHEASTERN MICHIGAN. CURRENT INDICITATIONS POINT TO
THE NORTHERN CWA AND PORTIONS CENTRAL LOWER MICHIGAN FOR THE MOST
FAVORABLE TRACK OF THIS WIDESPREAD SHOWER ACTIVITY.
FOR DTW...BEEN A VERY DIFFICULT TIME TRYING TO PIN DOWN OVERALL
POTENTIAL FOR IFR CIGS TODAY WITH IFR CIGS IN PLACE TO THE
IMMEDIATE SOUTH OF THE DTW TERMINAL. ARC OF SHOWERS IS LIFTING
SLOWLY NORTHWARD. MODELS KEEP THIS ACTIVITY IN VICINITY OF THE
TERMINAL UNTIL 00Z. QUIET THIS EVENING BEFORE...RAIN AND
BORDERLINE VFR/MVFR CIGS LIFT NORTHWARD TOWARD THE TERMINAL AROUND
9Z.
//DTW THRESHOLD PROBABILITIES...
* HIGH FOR CEILING AOB 5000 FEET FOR MUCH OF THE FORECAST
PERIOD.
* HIGH FOR PRECIPITATION FALLING AS RAIN TODAY AND TONIGHT.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...SMALL CRAFT ADVISORY UNTIL 10 PM EDT WEDNESDAY FOR LHZ421-441.
SMALL CRAFT ADVISORY UNTIL 4 PM EDT WEDNESDAY FOR LHZ442.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
SHORT TERM...CB
LONG TERM....RK
MARINE.......RK
AVIATION.....CB
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
137 PM EDT TUE APR 7 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 421 AM EDT TUE APR 7 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR MI UNDER A
CONFLUENT WNW FLOW ALOFT BTWN ARCTIC BRANCH CLOSED LO OVER NRN
QUEBEC AND SRN BRANCH RDG IN THE PLAINS DOWNSTREAM OF TROF ALONG THE
W COAST. UPR MI REMAINS IN THE RRQ OF 130KT H3 JET MAX WITHIN THE
CONFLUENCE ZN OF THESE TWO BRANCHES. WV IMAGERY AND RUC ANALYSIS
ALSO INDICATE A SHRTWV OVER NDAKOTA THAT IS SLIDING TO THE E. THE
DPVA/MID LVL QVECTOR CNVGC AHEAD OF THIS SHRTWV AND SOME UPR
DVGC/MID LVL FGEN IN THE RRQ OF THE UPR JET ARE AIDING A LINE OF
LIGHT SN/MIXED PCPN ACRS NCENTRAL WI INTO FAR SRN MNM COUNTY WELL TO
THE N OF FAIRLY SHARP H85 WARM FNT ORIENTED W-E ACRS THE LOWER LKS.
HOWEVER...THE NNE LLVL FLOW OF VERY DRY AIR SHOWN ON THE 00Z INL
RAOB TO THE S OF HI PRES STRETCHING FM NEAR LK WINNIPEG ACROSS NW
ONTARIO AND INTO QUEBEC IS PREVENTING THIS PCPN FM MOVING FARTHER TO
THE N. BUT THERE ARE PLENTY OF MID/HI CLDS OVER THE CWA...THICKEST
OVER THE SRN TIER. LOOKING FARTHER UPSTREAM...ANOTHER SHRTWV IS
LIFTING TOWARD THE NRN PLAINS IN THE SW FLOW ALOFT BTWN THE PLAINS
RDG AND THE TROF ALONG THE W COAST.
MAIN FCST CONCERNS THRU TNGT WL BE POPS ALONG THE WI BORDER EARLY
THIS FCST PERIOD IN ASSOCIATION WITH THE SHRTWV NOW APRCH MN. FOCUS
FOR TNGT WL BE ON IMPACT OF SECOND DISTURBANCE APRCHG THE NRN PLAINS
AND ANOTHER DISTURBANCE THE MODELS SHOW WL MOVE THRU WI.
TDAY...FIRST SHRTWV OVER NW MN IS FCT TO DRIFT TO THE E AND INTO RRQ
OF UPR STREAK TO THE E...ACCOMPANIED BY AN AREA OF DEEP LYR QVECTOR
CNVGC. ALTHOUGH THIS SETUP WOULD NORMALLY SUPPORT WDSPRD PCPN...ALL
THE MODELS SHOW A STEADY FEED OF SFC-H85 DRY AIR FM THE NE THRU THE
DAY. IN FACT...AFTER LINGERING PCPN ENDS EARLY THIS MRNG OVER FAR
SRN MENOMINEE COUNTY...ALL OF THE MODELS SHOW NO PCPN OVER UPR MI
THRU 00Z THIS EVNG. BUT WITH CONSIDERABLE MID/HI CLD ABOVE THE LLVL
DRY AIR AND AN ENE WIND OFF THE CHILLY LK WATERS...MAX TEMPS THIS
AFTN SHOULD RUN BLO NORMAL. EXPECT READINGS TO REACH THE LO 40S AWAY
FM THE LKS...WHERE TEMPS WL HOLD IN THE 30S.
TNGT...AS THE CONFLUENCE ZN SHIFTS SLOWLY TO THE NE TDAY...SHRTWV
NOW TRACKING INTO THE NRN PLAINS IS FCST TO LIFT NE INTO SCENTRAL
CANADA...WITH BULK OF DEEP LYR QVECTOR CNVGC PASSING TO THE NW. BUT
GENERAL MODEL CONSENSUS ALSO HINTS ANOTHER SHRTWV EMERGING FM THE
WRN TROF AND THRU THE PLAINS TDAY WL DRIFT INTO WI LATE TNGT...
ACCOMPANIED BY AREA OF FAIRLY SHARP UPR DVGC EVEN AS THE MAIN UPR
JET CORE TO THE E SLIPS FARTHER AWAY ALONG WITH THE UPR CONFLUENCE
ZN. MOST OF THE MODELS FOCUS SOMEWHAT HIER QPF OVER THE SCNTRL
CWA...CLOSER TO WHERE THE CORE OF UPR DVGC/AXIS OF SHARPEST MID LVL
FGEN TO THE N OF H85 WARM FNT THAT IS FCST TO LIFT NWD WITH THE APRCH
OF THIS DISTURBANCE. DESPITE THE GENERAL AGREEMENT ON THESE
FEATURES...MODEL QPF AND FCST THERMAL FIELDS ARE QUITE VARIABLE. THE
GFS IS WETTEST OVERALL...SHOWING AS MUCH AS 0.25-0.35 INCH OVER THE
SCNTRL CLOSER TO THE SHARPER FORCING/FGEN AND WHERE THIS MODEL SHOWS
H7 SPECIFIC HUMIDITY IN THE 3-4 G/KG RANGE. BUT MANY OF THE HIER RES
MODELS...LIKE THE 00Z NAM AND REGIONAL CNDN...SHOW LTL IF ANY PCPN
EVEN THERE. GIVEN PERSISTENCE OF LLVL DRY AIR OVER THE NE CWA AND THE
WEAKENING OF THE FORCING WITH TIME AS THE DISTURBANCE LIFTS TO THE
NE...WL TEND TO KEEP THE NE CWA DRIER LONGER. PTYPE WL BE A
CONCERN...AND MODEL DIFFERENCES COMPOUND THE UNCERTAINTY. SINCE THE
GFS SHOWS MORE VERTICAL MOTION/QPF AND THUS MORE DYNAMIC/EVAPORATIVE
COOLING...THAT MODEL FCST SDNGS INDICATE A MAINLY SN EVENT...WITH SN
AMOUNTS OVER THE SCENTRAL AT LEAST APRCHG ADVY CRITERIA. CONSIDERING
THE WIDE DIFFERENCES IN QPF/IMPACT OF LINGERING DRY AIR...DID NOT
CONSIDER AN ADVY ATTM EVEN THOUGH TRACK OF DISTURBANCE TO THE S AND
VERY DRY NATURE OF THE ANTECEDENT AIRMASS WOULD FAVOR MAINLY SN. MANY
OF THE OTHER MODELS SHOW AN ELEVATED WARM LYR WITH MAX TEMPS ALOFT
OVER 0C. WITH LLVL DRY AIR THAT WL ALLOW FOR MORE NEAR SFC
COOLING...FREEZING RA AND PERHAPS SLEET...ESPECIALLY NEAR THE ONSET
OF THE PCPN WHEN THE LLVLS ARE DRIER AND WBLB TEMPS LO ENUF TO ALLOW
FOR A BETTER CHC FOR THE DROPS TO FREEZE INTO ICE PELLETS...ARE
POSSIBLE. SO RETAINED A MENTION OF THESE PTYPES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 359 AM EDT TUE APR 7 2015
THE SECOND HALF OF THE WORK WEEK CONTINUES TO LOOK ACTIVE WITH
PERIODS OF MIXED PRECIPITATION...BEFORE TRENDING DRIER WITH NORMAL
TO ABOVE NORMAL TEMPERATURES THIS WEEKEND. ANOTHER UPPER TROUGH
WILL AFFECT THE REGION FOR THE START OF NEXT WEEK...BUT AT THIS
POINT...THERMAL PROFILES SUPPORT RAIN FOR THE PRECIP TYPE.
TO START THE LONG TERM PERIOD...THE SHORTWAVE THAT WILL BE
PRODUCING PRECIPITATION OVER PARTS OF THE UPPER GREAT LAKES REGION
WILL BE QUICKLY SHIFTING EAST OUT OF THE THE AREA WEDNESDAY MORNING.
THIS MAY LEAD TO SOME LINGERING SHOWERS TO DURING THE MORNING AND
WITH THE DEEP MOISTURE DEPARTING IT WILL LEAD TO A WINTRY MIX IF
PRECIPITATION OCCURS. WHILE THE LARGE SCALE SUPPORT DEPARTS AT THE
START OF THE PERIOD...THE HIGH PRESSURE RIDGE WILL ALSO QUICKLY
LEAVE THE REGION AND ALLOW FOR PLENTY OF CLOUDS TO REMAIN OVER THE
U.P. FOR WEDNESDAY. THE LATEST TRENDS IN THE MODELS IS FOR LOW LEVEL
MOISTURE TO REMAIN OVER THE AREA...AND WITH SOUTHEASTERLY 950-925MB
FLOW DEVELOPING THROUGH THE DAY...EXPECT THERE TO BE SOME UPSLOPE
DRIZZLE FOR THE HIGHER TERRAIN OF CENTRAL UPPER MICHIGAN. THE
GFS CONTINUES TO HIGHLIGHT EVEN MEASURABLE DRIZZLE BUT WITH MUCH OF
THE OTHER MODELS SHOWING DRY NEAR SURFACE AIR...WILL ONLY SHOW
SLIGHT CHANCE POPS FOR THE DRIZZLE.
ATTENTION THEN TURNS TO THE UPPER TROUGH LIFTING NORTHEAST OUT OF
THE CENTRAL PLAINS WEDNESDAY NIGHT AND PHASING WITH A WAVE MOVING
THROUGH CANADA THURSDAY AFTERNOON INTO THURSDAY NIGHT AS IT MOVES
THROUGH THE UPPER GREAT LAKES REGION. THERE CONTINUES TO BE TWO
WAVES OF PRECIPITATION EXPECTED WITH THIS SYSTEM. THE FIRST WILL BE
TIED TO THE STRONG WARM AIR ADVECTION AND LEADING SHORTWAVE LIFTING
NORTHEAST THROUGH THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY
MORNING. MODEL CONSENSUS HAS THE BEST SHORTWAVE ENERGY MISSING THE
U.P. TO THE SOUTHEAST BUT THEY DIFFER ON WHERE THE FOCUS OF THE BEST
WARM AIR ADVECTION WILL BE OVER THE U.P. THUS...CONFIDENCE REMAINS
LOW ON THE TRACK OF THE HEAVIEST PRECIPITATION (0.15-0.3IN OF
LIQUID...HIGHEST OVER THE SOUTH CENTRAL). AS FOR PRECIP TYPE...WITH
900-800MB TEMPERATURES WELL ABOVE FREEZING WITHIN THAT BEST
FORCING...WOULD EXPECT THE PRECIPITATION TO FALL AS RAIN. WHICH
LEAVES THE SURFACE TEMPERATURES TO DETERMINE WHETHER IT IS FREEZING
RAIN OR NOT. ONE POSITIVE WITH THE WARMER WEATHER OVER THE LAST
COUPLE OF WEEKS IS THAT IT HAS HELPED WARM THE SURFACE TEMPERATURES
ACROSS THE AREA. TODAY...EVEN WITH THE COOLER TEMPERATURES...ROAD
SURFACE TEMPERATURES WERE IN THE MID-UPPER 30S. THUS...WITH THE
CLOUDS ON WEDNESDAY INTO WEDNESDAY NIGHT HELPING TO INSULATE AND
KEEP LOWS AROUND 30 DEGREES (TRENDED THEM UP A COUPLE DEGREES)...THE
IMPACT OF THE FREEZING RAIN MAY BE A LITTLE LESS (ESPECIALLY IF
ROADS ARE TREATED IN ADVANCE). WILL CONTINUE TO ADDRESS THIS
FREEZING RAIN THREAT IN THE HWO.
AFTER A BRIEF LULL IN THE STRONGER PRECIPITATION ON THURSDAY
AFTERNOON...THE UPPER TROUGH WILL LIFT NORTHEAST THROUGH THE UPPER
GREAT LAKES REGION THURSDAY NIGHT INTO FRIDAY MORNING WHILE THE
SURFACE LOW TRACKS FROM CENTRAL IOWA AT 18Z THURSDAY TO NORTHERN
LAKE HURON AT 18Z ON FRIDAY. VERY CONFIDENT ON PRECIPITATION
OCCURRING DURING THAT PERIOD...BUT CONFIDENCE IS LACKING ON THE
AMOUNTS/LOCATION DUE TO DIFFERENCES WITH THE TRACK/INTENSITY OF THE
LOW AND THE MID LEVEL FGEN BAND. THIS IS ALL TIED TO THE PHASING OF
THE TWO WAVES...WHICH IS NOTORIOUSLY DIFFICULT FOR MODELS TO PIN
DOWN AT THIS STAGE. THUS...WILL FOLLOW A GENERAL CONSENSUS OF THE
MODELS (LEANING TOWARDS GFS/ECMWF) BOTH FOR QPF AND THERMAL FIELDS
AS THAT SEEMS TO REPRESENT THE POSSIBILITIES THE BEST AT THIS TIME.
AT THIS POINT...THINK THE GEM/NAM SEEM LIKE THE OUTLIERS WITH THE
FARTHER NORTHWEST TRACK (ALONG LAKE MICHIGAN AND THE U.P. SHORELINE)
WITH THE 12Z ECMWF AND 00Z GFS ENSEMBLE MEMBERS SUPPORTING A TRACK
MORE THROUGH NORTHERN LOWER MICHIGAN. THE LATE ARRIVING 00Z ECMWF
REMAINS MUCH WEAKER THAN THE OTHER SOLUTIONS...AS IT HAS
TRENDED TOWARDS LESS PHASING AND MORE OF A GLANCING BLOW BY THE
NORTHERN STREAM WAVE. IF THAT VERIFIES...IT WOULD LEAD TO MUCH LESS
PRECIPITATION FOR THE AREA FOR THE THURSDAY NIGHT PERIOD AND DRY BY
FRIDAY AFTERNOON. EXPECT THE PRECIP TO START AS RAIN INITIALLY AND
THEN GRADUALLY TRANSITION TO OR MIX WITH SNOW FROM WEST TO EAST.
WITH ALL OF THE UNCERTAINTY...DON/T WANT TO GET TOO HUNG UP IN
SNOWFALL AMOUNTS...BUT THERE COULD BE SLUSHY ACCUMULATIONS WEST OF
A LINE FROM MARQUETTE TO CRYSTAL FALLS. THIS SECOND WAVE OF PRECIP
IS STILL AN EVOLVING SITUATION THAT WILL NEED TO BE FINE TUNED OVER
THE NEXT SEVERAL SHIFTS.
THE UPPER TROUGH AND SURFACE LOW WILL QUICKLY DEPART FRIDAY NIGHT
AND BRING A QUICK DRYING TREND TO THE AREA AS A SURFACE RIDGE MOVES
EAST OVER THE AREA BY SATURDAY MORNING. WITH LIMITED COLD AIR
BEHIND THIS SYSTEM AND AN UPPER RIDGE MOVING INTO THE UPPER GREAT
LAKES REGION...SHOULD SEE NEAR NORMAL TEMPERATURES ON SATURDAY WITH
MOSTLY SUNNY SKIES. THAT UPPER/SURFACE RIDGE WILL SHIFT EAST ON
SATURDAY NIGHT...LEADING TO SOUTHWESTERLY WINDS BRINGING WARMER AIR
TO THE AREA FOR SUNDAY AND HAVE HIGHS RISING INTO THE UPPER 50S
OVER THE WEST AND AROUND 50 OVER THE EAST. THAT SOUTHWESTERLY FLOW
WILL BE OUT AHEAD OF THE NEXT UPPER TROUGH THAT WILL BE MOVING
ACROSS THE CANADIAN ROCKIES THIS WEEKEND AND IMPACTING THE AREA
SUNDAY NIGHT INTO THE FIRST PART OF NEXT WEEK. AT THIS POINT...THE
THERMAL PROFILES WOULD SUPPORT RAIN FOR MONDAY AND WILL SHOW
INCREASING POPS SUNDAY NIGHT AND CONTINUE CHANCE POPS INTO MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 135 PM EDT TUE APR 7 2015
A STEADY ENE WIND ON THE SRN FLANK OF HIGH PRES RIDGE EXTENDING
ACROSS NRN ONTARIO WILL CONTINUE TO ADVECT LOW-LEVEL DRY AIR INTO
UPPER MI THRU THIS EVENING...RESULTING IN VFR CONDITIONS AT
KIWD/KCMX/KSAW DESPITE CONSIDERABLE MID CLOUDS. AS A DISTURBANCE
MOVES INTO THE GREAT LAKES TONIGHT...LIGHT PCPN WILL PROBABLY AFFECT
ALL TERMINALS LATE TONIGHT INTO WED MORNING. ALONG WITH -SN...THERE
MAY BE SOME -RA/-FZRA...THOUGH CONFIDENCE IS QUITE LOW ON PTYPE.
EXPECT MVFR CONDITIONS TO EVENTUALLY DEVELOP...AND LINGER THRU THE
END OF THE FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 421 AM EDT TUE APR 7 2015
WITH LAKE SUPERIOR SITUATED BETWEEN HI PRES THAT WILL MOVE ACROSS NW
ONTARIO INTO QUEBEC THRU WED AND A WARM FRONT THAT WILL REMAIN TO
THE S AND SW ACROSS THE PLAINS TO OHIO VALLEY...E TO NE WINDS WILL
PERSIST. TYPICAL FOR E TO NE WINDS...WINDS WILL BE STRONGEST OVER
WRN LAKE SUPERIOR...IN PARTICULAR BTWN THE APOSTLE ISLANDS AND MN
NSHORE WHERE FUNNELING/COASTAL CONVERGENCE ENHANCE THE WINDS. IN
THAT AREA...15-25KT WINDS WILL INCREASE TO 20-30KT THIS MORNING INTO
THIS EVENING. E TO NE WINDS...MOSTLY 10-20KT...WILL THEN CONTINUE ON
WED AND ON INTO THU AS LO PRES LIFTS NE FROM THE CENTRAL PLAINS
TOWARD THE GREAT LAKES REGION. AT THIS TIME...NO GALES APPEAR
LIKELY. BUT WINDS WILL BACK TO THE N AND THEN NW UP TO 25 KTS THU
NIGHT INTO FRI ONCE THE LO SHIFTS TO THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1210 PM EDT TUE APR 7 2015
LATEST UPDATE...
HYDRO
.SYNOPSIS...
ISSUED AT 329 AM EDT TUE APR 7 2015
THE AREA WILL SEE A RELATIVELY WET PERIOD THROUGH MOST OF THE REST
OF THIS WEEK. A STALLED OUT FRONTAL SYSTEM WILL REMAIN IN THE
REGION. THE AREA WILL BE ON THE COOL NORTH SIDE OF THIS FRONT
THROUGH WEDNESDAY. ROUNDS OF SHOWERS AND EVENTUALLY STORMS CAN BE
EXPECTED. THE FRONT WILL LIFT NORTH OF THE AREA ON THURSDAY AND
BRING WARMER AIR INTO THE AREA. STORMS WILL BECOME MORE LIKELY ON
THURSDAY WITH A THREAT FOR SOME SEVERE WEATHER POSSIBLE DOWN SOUTH.
CONDITIONS WILL QUIET DOWN THEN FOR THE END OF THE WORK WEEK AND
NEXT WEEKEND AS THE ENTIRE FRONTAL SYSTEM PUSHES OUT OF THE AREA.
&&
.UPDATE...
ISSUED AT 1142 AM EDT TUE APR 7 2015
BEST COVERAGE OF SCATTERED RAIN SHOWERS THIS AFTERNOON SHOULD BE
SOUTH OF I-96 CLOSER TO THE H8 BAROCLINIC ZONE. LATEST HRRR IS
FAVORING THE AREA EAST AND SOUTH OF A LINE FROM AZO TO LAN.
FARTHER NORTH AND WEST... MAINLY ISOLATED COVERAGE OF SHOWERS AT
BEST. H5 PROGS SHOW SEVERAL VORTICITY MAXIMA EMBEDDED IN ZONAL
FLOW ALOFT SO AM RELUCTANT TO GO COMPLETELY DRY IN THE NRN CWFA
AFTER 18Z. TEMPS WILL STRUGGLE TO GET OUT OF THE 40S THIS AFTEROON
WITH CLOUDS AND BRISK EAST FLOW.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 329 AM EDT TUE APR 7 2015
OUR MAIN CHALLENGES IN THE SHORT TERM WILL BE DETERMINING SEVERE
WEATHER CHANCES FOR THU...AND TIMING ROUNDS OF RAIN THROUGH THE AREA
THROUGH THU.
WE ARE SEEING A COUPLE OF AREAS OF RAIN SHOWERS MOVING THROUGH THE
AREA EARLY THIS MORNING. THESE RAIN SHOWERS ARE INSIGNIFICANT AS THE
MUCH BETTER MOISTURE REMAINS WELL SOUTH OF THE AREA SOUTH OF THE
COLD FRONT THAT DROPPED THROUGH THE AREA LAST EVENING. THE RAIN
SHOWERS REMAIN ASSOCIATED WITH A RRQ OF A 130 KNOT UPPER JET STREAK
THAT IS LEADING TO SOME MID LEVEL FGEN PROCESSES OVER THE AREA. WE
EXPECT MOST OF THIS TO BE GONE BY 12Z THIS MORNING.
AFTER A BREAK FOR MOST OF THE DAY TODAY...WE WILL SEE PCPN MOVE BACK
IN/DEVELOP OVER THE AREA BEGINNING TOWARD MIDNIGHT TONIGHT. THIS
PCPN WHICH SHOULD BE ALMOST ALL RAIN PER FCST SOUNDINGS WILL BE A
BIT MORE ROBUST. WE WILL SEE AN UPPER WAVE MOVE INTO THE AREA ON THE
SW FLOW ALOFT. THIS WAVE WILL HAVE BETTER SUPPORT AS THE LLJ WILL BE
AIMED CLOSER TO THE AREA BRINGING BETTER MOISTURE TO THE AREA. LATER
ON TONIGHT...THUNDER WILL BECOME POSSIBLE AS SUFFICIENT ELEVATED
INSTABILITY MOVES UP TO JUST SOUTH OF I-96. THE ELEVATED NATURE OF
THE STORMS WILL KEEP THE SEVERE THREAT FAIRLY LOW.
WE WILL HAVE A SIMILAR SET UP FOR THE WED/WED NIGHT TIME FRAME. WE
SHOULD SEE A BREAK FOR MOST OF THE AREA ON WED AS THE LLJ/MOISTURE
TRANSPORT CORE SHIFTS EAST. YET ANOTHER UPPER WAVE AND ASSOCIATED
LLJ/MOISTURE TRANSPORT AREA WILL MOVE IN ACROSS THE AREA FOR WED
NIGHT. THERE WILL BE A BETTER THREAT FOR STORMS ACROSS THE ENTIRE
CWFA AS A PLUME OF BETTER ELEVATED INSTABILITY MOVES IN. SEVERE WX
THREAT IS STILL LOW THROUGH WED NIGHT WITH THE INSTABILITY BEING
ELEVATED AND FCST SOUNDINGS INDICATING A LOWER THREAT FOR ALL OF THE
THREATS.
THU WILL BE THE DAY THAT PORTIONS OF THE AREA WILL SEE THE BEST CHC
FOR SOME SEVERE WX. WE WILL SEE THE MAIN LONG WAVE TROUGH ACROSS THE
WRN STATES LIFT NE TOWARD THE UPPER MIDWEST. THIS WILL LIFT THE
FRONT BACK NORTH ACROSS AT LEAST A PORTION OF THE AREA. HOW FAR
NORTH THE FRONT GOES WILL MAKE A BIG DIFFERENCE IN TEMPS AND SEVERE
WX THREAT WITH QUITE A TEMP GRADIENT ACROSS THE FRONT.
WE ARE TENDING TO THINK THE FRONT WILL LIFT TO ABOUT I-96 OR JUST
NORTH AS SOME OF THE MODELS SEEM TO BE OVERDEVELOPING THE SFC LOW
WITH THIS SYSTEM DUE TO EARLIER CONVECTION. THE WARM SECTOR COULD
SEE TEMPS GET INTO THE 70S WITH DEW POINTS POSSIBLY GETTING WELL
INTO THE 50S. THIS WOULD GENERATE SOME VALUES OF CAPE OVER 1000
J/KG. THE WARM FRONT WOULD BE A CONCERN WITH SOME DECENT DIRECTIONAL
SHEAR AS ONE WOULD EXPECT. SOME LARGE HAIL AND DAMAGING WINDS WOULD
BE POSSIBLE IN THE WARM SECTOR WITH FAIRLY HEALTHY CAPE IN THE -10
TO -30C LAYER AND UNIDIRECTIONAL WINDS. RAIN EARLIER ON MAY LIMIT
INSTABILITY SOME.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 329 AM EDT TUE APR 7 2015
THE LONG TERM LOOKS WET AT THE BEGINNING AND END BUT DRY OVER MUCH
OF THE WEEKEND.
WE/RE GOING TO HANG ONTO THE POSSIBILITY OF THUNDERSTORMS THURSDAY
NIGHT. THE GFS REMAINS SLOWER THAN THE ECMWF WHICH ALREADY MOVES LOW
PRESSURE OVER THE CENTRAL CWA BY 00Z FRIDAY. MEANWHILE THE GFS STILL
HAS THE LOW OVER EASTERN IOWA AND THE CWA IN THE WARM SECTOR. IF THE
ECMWF IS CORRECT...TSRA CHANCES WOULD BE LOWER THAN IF THE SLOWER
GFS VERIFIES. BOTH MODELS CLEAR THE TRAILING COLD FRONT BY FRIDAY
MORNING WHICH MEANS WE/LL DRY OUT FRIDAY LEADING TO SUNNY WEATHER
SATURDAY AND SUNDAY.
THE NEXT SIGNIFICANT WEATHER WILL BE A SOUTHERN STREAM LOW THAT
MOVES NORTHEAST FROM TEXAS LATE SUNDAY NIGHT AND MONDAY. THE GULF
LOOKS TO BE WIDE OPEN SO MOISTURE AVAILABILITY SHOULDN/T BE A
PROBLEM ESPECIALLY GIVEN THE 60+ KT LLJ. THIS LOOKS MOSTLY LIKE A
RAIN EVENT AS INSTABILITY APPEARS LIMITED.
TEMPS IN THE MID 50S FRIDAY WILL WARM TO THE MID 60S BY SUNDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 745 AM EDT TUE APR 7 2015
RADAR SHOWS LIGHT SHOWERS INCREASING OVER SOUTHWEST LOWER
MICHGIAN. SHOWERS WILL REMAIN IN THE VICINITY OF THE TAF SITES
THIS MORNING BUT LIKELY WON/T RESTRICT VISIBILITIES.
NORTHEAST WINDS HAVE ADVECTED IFR/MVFR CIGS FROM SAGINAW BAY INTO
LANSING AND JACKSON. IT/S POSSIBLE THAT WE/LL SEE THESE CIGS
BOUNCE AROUND A BIT...AS LANSING HAS JUST SCATTERED OUT. IFR CIGS
SHOULD BE A THREAT UNTIL WINDS VEER MORE TO THE EAST RATHER THAN
NORTHEAST AND TAKE THE LAKE OUT OF PLAY.
&&
.MARINE...
ISSUED AT 329 AM EDT TUE APR 7 2015
WE WILL BE LEAVING THE SMALL CRAFT ADVISORY AS IS WITH THIS FCST
PACKAGE. A FAIRLY STIFF E/NE GRADIENT WILL REMAIN IN PLACE THROUGH
TODAY AND INTO WED MORNING. WAVES WILL NOT BE TOO SIGNIFICANT ON
THIS SIDE OF THE LAKE WITH THE OFFSHORE COMPONENT.
&&
.HYDROLOGY...
ISSUED AT 1210 PM EDT TUE APR 7 2015
RIVER AND STREAM LEVELS ACROSS SOUTHWEST LOWER MICHIGAN ARE RUNNING
NEAR TO A LITTLE BELOW NORMAL. RIVER LEVELS ARE CURRENTLY SLOWLY
FALLING... BUT RISES IN RIVER LEVELS DUE TO RAINFALL ARE EXPECTED
LATER THIS WEEK. 1 TO 2 INCHES OF WIDESPREAD RAINFALL IS POSSIBLE
OVER THE NEXT 7 DAYS. THERE IS ALSO A POTENTIAL FOR LOCALLY GREATER
RAINFALL AMOUNTS... IF THUNDERSTORMS MOVE OVER THE SAME AREAS. IN
GENERAL...SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED
WEDNESDAY NIGHT INTO FRIDAY. PONDING OF WATER AND URBAN AND SMALL
STREAM FLOODING IS POSSIBLE... THOUGH RIVERS SHOULD REMAIN MOSTLY
WITHIN THEIR BANKS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT WEDNESDAY FOR LMZ844>849.
&&
$$
UPDATE...MEADE
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...99
AVIATION...04
HYDROLOGY...63
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
337 PM CDT TUE APR 7 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 330 PM CDT TUE APR 7 2015
CURRENT CONDITIONS SYNOPSIS...
CLUSTER OF SHOWERS AND EMBEDDED THUNDERSTORMS CURRENTLY MOVING
THROUGH THE SOUTHERN PORTION OF THE AREA ALONG THE NORTHERN
PERIPHERY OF THE INSTABILITY... WITH A NOTABLE GRADIENT IN MUCAPE
JUMPING FROM 0 TO 500 J/KG SOUTH OF THE BORDER. DEEP LAYER SHEAR IS
STRONG... AND ONE STORM DID BRIEFLY SHOW SOME MID-LEVEL
ROTATION... AND MANAGED TO PRODUCE MARGINALLY SEVERE HAIL. THE
ACTIVITY SHOULD TRANSLATE EAST AND FOCUS MORE SOUTH AS THE
SHORTWAVE EVIDENT ON WATER VAPOR NEAR THE NEBRASKA/IOWA BORDERS
SHIFTS EAST THROUGH EARLY EVENING.
FORECAST ITEM/S/ OF CONCERN...
CHANCES FOR PCPN... SOME THUNDER... AND PERHAPS SOME MIXED PCPN INTO
TONIGHT... WITH THINGS DRYING OUT WEDNESDAY.
MODEL DISCUSSION/PREFERENCES...
PRIMARILY RELYING ON CAM GUIDANCE... PARTICULARLY HRRR AND HOPWRF
MEMBERS... WHICH HAVE A DECENT HANDLE ON CURRENT CONVECTIVE ACTIVITY
ACROSS THE AREA... BLENDING MORE TOWARD NAM/GFS SOLUTIONS ON
WEDNESDAY.
SENSIBLE WEATHER EXPECTATIONS...
EXPECT SHRA AND EMBEDDED TSRA TO IMPACT THE SOUTHERN PORTION OF THE
AREA INTO PERHAPS THE EARLY EVENING... OTHERWISE WILL SEE PCPN ON
THE NORTH SIDE OF SURFACE LOW MOVE EAST ACROSS THE AREA THROUGH THE
REMAINDER OF THE EVENING. SOME SLEET COULD MIX IN AT TIMES OVER THE
NORTH AND NORTHEAST PORTION OF THE AREA WHERE THE WARM LAYER IS A
BIT LESS DEEP. SHOULD SEE ENOUGH DRYING/SUBSIDENCE IN THE MID-LEVELS
FOR PCPN TO COME TO AN END LATER TONIGHT... WITH DRY WEATHER OTHER
THAN PERHAPS SOME PATCHY DRIZZLE THROUGH MOST OF WEDNESDAY. SOME
SHRA COULD WORK BACK INTO THE SOUTHERN PART OF THE AREA BY LATER
WEDNESDAY AS THE NEXT SHORTWAVE AND SURFACE IMPULSE ALONG THE
BAROCLINIC ZONE WORK INTO THE REGION.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 330 PM CDT TUE APR 7 2015
THE STORM SYSTEM OFF THE COAST OF CALIFORNIA WILL IMPACT OUR
REGION FROM WEDNESDAY NIGHT THRU EARLY FRIDAY MORNING. THE FIRST
PART OF THE STORM HAS THE POTENTIAL OF SVR WX IN THE FAR SE BASED
ON STABILITY PARAMETERS...LOW FREEZING LEVEL AND MID LEVEL LAPSE
RATES. THE BEST POTENTIAL WILL BE THURSDAY AFTERNOON FROM ALBERT
LEA...NORTHEAST TO EAU CLAIRE WISCONSIN. SEE THE LATEST SPC DAY 3
OUTLOOK.
SEVERAL FACTORS NEED TO COME TOGETHER FOR SNOWFALL TO ACCUMULATE
IN OUR CWA. FIRST...THE BEST CHC OF PRECIPITATION AND HIGHER
PRECIPITATION RATES OCCUR BETWEEN 18Z THU TO 06Z FRIDAY. THE SFC
LOW REMAINS IN A FAVORABLE TRACK FOR THE PRECIPITATION TO CHANGE
OVER TO SNOW DURING THE LATE AFTN/EVENING. HOWEVER...THERMAL
PROFILERS REMAINED UNFAVORABLE OF THIS CHANGE OVER IN OUR
CWA...WITH ONLY A SMALL AREA OF THICKNESS VALUES DROPPING TO
CRITICAL LEVELS IN EC MN/WC WI THURSDAY EVENING. THERE REMAINS A
VERY STRONG SIGNAL OF A TROWAL AND DEFORMATION ZONE DEVELOPMENT IN
EC MN/WC WI THURSDAY EVENING. AS WITH PREVIOUS DISCUSSIONS...THERE
IS A POTENTIAL OF HEAVY SNOWFALL IN A SMALL BAND IF ALL THE
WEATHER ELEMENTS COME TOGETHER. IN ADDITION...A CROSS SECTION OF
THE ATMOSPHERE FROM WC MN TO SOUTHERN WI HAS EC MN IN FAVORABLE
AREA OF CONVECTIVE STABILITY INDEX /CSI/ AND SLATEWISE
CONVECTIVE. THEREFORE...IT IS HIGHLY PROBABLE FOR SOMEWHERE IN
EASTERN MN/WESTERN WI TO SEE A HEAVY SNOWFALL EVENT THURSDAY
EVENING IF THIS TYPE OF SCENARIO DEVELOPS.
PAST THURSDAY...A COOL PERIOD WILL OCCUR FROM FRIDAY THRU
SATURDAY BEFORE SOUTHERLY FLOW BEGINS. LATE IN THE WEEKEND AND
INTO NEXT WEEK REMAIN VERY UNSETTLED AS ANOTHER STORM SYSTEM
BEGINS TO DEVELOP ACROSS THE CENTRAL U.S. WITH THIS TYPE OF
PATTERN...TEMPS MAY FLUCTUATE RAPIDLY BASED ON THE AMOUNT CLOUD
COVER AND PRECIPITATION POTENTIAL...BUT AN OVERALL MEAN IS TO
CONTINUE WITH SLIGHTLY BLW NORMAL TEMPS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 330 PM CDT TUE APR 7 2015
HIGH CONFIDENCE OF WIDESPREAD RAINFALL ACROSS THE SE MPX FORECAST
AREA...WITH CIGS LOWERING THROUGHOUT THE NIGHT INTO THE IFR RANGE.
SOME IMPROVEMENT IS LIKELY WEDNESDAY AFTN BEFORE THE NEXT WAVE OF
PRECIPITATION DEVELOPS. EXPECT AN EAST TO EAST-SOUTHEAST WIND AROUND
10-15 KTS TONIGHT...BACKING TO THE E-NE BY WEDNESDAY AFTN.
KMSP...HIGH CONFIDENCE OF -SHRA LATE THIS AFTN/EARLY EVENING WITH
CIGS LOWERING. CIGS WILL LIKELY DROP TO IFR OVERNIGHT...AND SLOWLY
RISE WEDNESDAY AFTN. EXPECT AN EAST TO EAST-SOUTHEAST WIND AROUND
10-15 KTS TONIGHT...BACKING TO THE E-NE BY WEDNESDAY AFTN.
/OUTLOOK FOR KMSP/
THU...MVFR POSSIBLY IFR. RA/SN LIKELY. WINDS N 15-25 KTS.
FRI...VFR. WINDS NW 10-15 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...
LONG TERM...JLT
AVIATION...JLT
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
100 PM EDT TUE APR 7 2015
.SYNOPSIS...
UNSEASONABLY WARM AND HUMID WEATHER IS EXPECTED OVER THE NEXT FEW
DAYS WITH WEAK HIGH PRESSURE WELL OFF THE COAST. THERE IS A RISK
OF SHOWERS AND THUNDERSTORMS EACH DAY THROUGH SATURDAY WITH THE
HIGHEST POTENTIAL TODAY AND FRIDAY NIGHT INTO SATURDAY. A BACKDOOR
COLD FRONT WILL MAKE A QUICK VISIT LATE WEDNESDAY NIGHT. IT WILL
REMAIN WARM AND HUMID THROUGH FRIDAY. A COLD FRONT WILL USHER IN
SEASONABLE TEMPERATURES OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 100 PM TUESDAY...SATELLITE AND RADAR SUGGEST THE UPPER
DISTURBANCE IS OFFSHORE. CLOUDS HAVE FRAGMENTED A BIT INLAND
ALTHOUGH THE INSOLATION IS CAUSING DESTABILIZATION OF THE
BOUNDARY LAYER AND NEW CUMULUS TO FORM QUITE QUICKLY. FOR THIS
REASON SKY COVER WILL PROBABLY AVERAGE MOSTLY CLOUDY THROUGH THE
AFTERNOON. RADAR SHOWS SPRINKLES/SHOWERS ARE VERY FEW AND FAR
BETWEEN...AND I HAVE DOUBTS WE`LL SEE ANYTHING SUBSTANTIAL THROUGH
LATE AFTERNOON. HIGHS HAVE BEEN ADJUSTED DOWNWARD BY A DEGREE OR
TWO FOR MOST AREAS. DISCUSSION FROM 1000 AM FOLLOWS...
A WEAK UPPER LEVEL DISTURBANCE IS PASSING ACROSS THE EASTERN
CAROLINAS CURRENTLY. THIS FEATURE SHOWS UP QUITE WELL IN WATER
VAPOR IMAGERY...BUT UNFORTUNATELY IT HAS OUTRUN DEEP MOISTURE AND
SHOWER ACTIVITY IS DRYING UP AS IT APPROACHES THE COAST. I HAVE
KEPT IN SMALL POPS (20-40 PERCENT) FOR THE NEXT COUPLE OF HOURS
ALONG THE COAST BUT HAVE LITTLE FAITH ANYONE WILL SEE MORE THAN AN
ADDITIONAL .01 OR .02 INCHES BEFORE THIS ACTIVITY EITHER
COMPLETELY DISSIPATES OR MOVES OFFSHORE.
BEHIND THIS DISTURBANCE IMPLIED NET DOWNWARD ATMOSPHERIC MOTION
WILL PROBABLY LEAD TO SEVERAL HOURS OF PARTLY CLOUDY SKIES WITH
TEMPERATURES SOARING INTO THE LOWER 80S INLAND...EXCEPT 5-10
DEGREES COOLER NEAR THE COAST GIVEN THE COOL ONSHORE FLOW FROM
OCEAN WATER TEMPERATURES ONLY IN THE LOWER 60S. GIVEN DEWPOINTS
NOW RECOVERING WELL INTO THE 60S I EXPECT TO SEE A HEALTHY CUMULUS
DECK FILL IN. ANOTHER WEAK UPPER LEVEL DISTURBANCE WILL APPROACH
FROM THE NORTHWEST THIS EVENING...POSSIBLY ACCOMPANIED BY A LINE
OF SHOWERS AND THUNDERSTORMS. WHILE I WOULD LOVE TO SHOW RAIN WITH
THIS FEATURE MAKING IT DOWN INTO WILMINGTON (WHERE IT`S BEEN 10
DAYS WITHOUT MEASURABLE RAIN NOW) IT IS HARD TO FIND SUPPORT FOR
MORE THAN 30-40 POPS.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 AM TUESDAY...WEDNESDAY BRINGS UNSEASONABLE WARMTH AND
HUMIDITY. IN FACT, CONSIDERABLE INSTABILITY IS FORECAST TO DEVELOP
AWAY FROM THE STABILIZING EFFECT OF THE OCEAN. SO WE HAVE TWO OF
THE THREE INGREDIENTS FOR THUNDERSTORMS IN PLACE. THE THIRD
HOWEVER, LIFT, MAY BE A BIT LACKING. IN PART THIS MAY HINGE UPON
HOW STORMY TUESDAY ENDS UP AS AN ACTIVE DAY COULD LEAVE BEHIND
SOME OUTFLOW BOUNDARIES. THERE WILL CERTAINLY BE SOME UNEVENNESS
IN THE CLOUD COVER SO SOME DIFFERENTIAL HEATING BOUNDARIES MAY
DEVELOP AS WELL. WHERE POPS TEND TO FOCUS WEDNESDAY NIGHT (ALBEIT
CAPPED AT 20 FOR NOW) WILL DEPEND ON HOW FAR SOUTH A BACKDOOR COLD
FRONT SINKS. IT APPEARS THAT A FEW THUNDERSTORMS WILL TRAIN
EASTWARD ALONG ITS LENGTH, BUT NOT ALL MODELS ARE CONVINCED THAT
IT GETS TOO FAR INTO OUR AREA, IF AT ALL. REGARDLESS, THIS
BOUNDARY THEN HIGHTAILS IT BACK TO THE NORTH ON THURSDAY. THIS
ONCE AGAIN LEAVES THE AREA IN A SOUTHWESTERLY WARM AND MOIST FLOW
REGIME. INSTABILITY WILL ONCE AGAIN DEVELOP AND SOME ISOLATED
THUNDERSTORMS WILL BE POSSIBLE. THE ONSHORE FLOW COMPONENT WILL BE
A LITTLE MORE PRONOUNCED POSSIBLY KEEPING THE IMMEDIATE COAST
RAIN-FREE. TEMPERATURES WILL STILL BE ABOVE NORMAL BUT PERHAPS A
FEW DEGREES TEMPERED FROM THE WEDNESDAY HIGHS.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 300 AM TUESDAY... WE REMAIN IN THE WARM AND HUMID
PRE-FRONTAL REGIME ON FRIDAY BUT COLD FRONT WILL BE APPROACHING.
THIS SHOULD BE SUFFICIENT TO TOUCH OFF SCATTERED SHOWERS AND
THUNDERSTORMS THAT WILL CONTINUE INTO THE NIGHTTIME WITH ACTUAL
FROPA. THE ACTUAL PASSAGE OF THE FRONT WILL BE RATHER GRADUAL
ESPECIALLY SINCE IT WILL BE CHANGING ITS ORIENTATION AS IT ALIGNS
MORE WITH THE CONTINUED LOW AMPLITUDE ALOFT. SUNDAY AND MONDAY
WILL FEATURE A SLIGHT COOLDOWN BACK TO CLIMATOLOGICAL
TEMPERATURES. SUNDAY APPEARS TO BE RAIN-FREE WHEREAS SOME MOISTURE
MAY RETURN SUFFICIENTLY ON MONDAY FOR SOME LOW RAIN CHANCES.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 18Z...ISOLATED SHOWERS THIS AFTERNOON MAINLY BETWEEN THE INLAND
AND COASTAL TERMINALS. MVFR CIGS WILL RISE TO VFR MID-LATE AFTERNOON.
AT KCRE/KMYR THERE REMAIN A POTENTIAL FOR MVFR VSBYS IN BR WITH SCATTERED
STRATUS AROUND 500 FEET UNTIL MID-AFTERNOON AS A NEARLY SATURATED AIRMASS
MOVES ONSHORE.
THERE IS A POTENTIAL FOR SHOWERS/ISOLATED THUNDERSTORMS THIS EVENING WITH
BEST THUNDERSTORM POTENTIAL AT KFLO/KLBT. AFTER MIDNIGHT Z MVFR
VSBYS/-RA BR WILL DEVELOP. EXPECTED CLOUD COVER SHOULD LIMIT
POTENTIAL FOR IFR. VFR EXPECTED AFTER SUNRISE WITH LIGHT WNW
WINDS.
EXTENDED OUTLOOK...VFR. CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY...BEST
CHANCE FOR PRECIPITATION IS FRIDAY NIGHT INTO SATURDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 100 PM TUESDAY...WINDS ARE STILL BACKED AROUND MORE EAST TO
SOUTHEASTERLY THAN MODELS INDICATED. LATEST RUC AND HRRR WIND
FIELDS ARE TOO NOISY TO USE SO I HAVE MANUALLY ADJUSTED WIND
DIRECTIONS COUNTERCLOCKWISE. STRONGEST WIND SPEEDS ARE NEAR AND
NORTH OF THE WEAK LOW OUT BEYOND FRYING PAN SHOALS...12-15 KT
NORTH OF CAPE FEAR...WITH 10 KT OR LESS FOR THE SC WATERS.
DISCUSSION FROM 1000 AM FOLLOWS...
SYNOPTIC HIGH PRESSURE IS WELL OFF THE COAST. WHAT APPEARS TO BE
MAINLY A MID-LEVEL CIRCULATION HAS FORMED WITHIN A LARGE AREA OF
RAIN AND EMBEDDED CONVECTION OFF THE COAST THIS MORNING. ALTHOUGH
I HAVEN`T SEEN MUCH INCREASE IN WIND VELOCITY...WIND DIRECTIONS
HAVE BEEN PERTURBED COUNTERCLOCKWISE BY THIS FEATURE WITH EAST
FLOW ALONG THE CAPE FEAR COAST BACKING TO NORTHEASTERLY ALONG THE
GRAND STRAND DOWN TOWARD GEORGETOWN.
THIS FEATURE SHOULD PUSH OFFSHORE THIS AFTERNOON WITH THE SYNOPTIC
SOUTHERLY WIND REESTABLISHING ITSELF. A WEAK SEABREEZE CIRCULATION
SHOULD AUGMENT THIS WIND...WITH SOUTH WINDS GENERALLY IN THE 10-15
KT RANGE THROUGH THIS EVENING. ONCE ANY LINGERING MORNING RAIN
CLEARS THE CAPE FEAR REGION...GENERALLY DRY CONDITIONS ARE
EXPECTED ACROSS THE COASTAL WATERS. THE APPROACH OF ANOTHER WEAK
DISTURBANCE THIS EVENING MAY GENERATE SOME MORE SHOWERS AND
THUNDERSTORMS...BUT THESE MAY HAVE TROUBLE MAKING IT DOWN BEYOND
THE COASTLINE DUE TO COOLER AND MORE STABLE AIR STREAMING ONSHORE
ACROSS THE COLD NEARSHORE WATER TEMPS.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 AM TUESDAY... WEDNESDAY WILL BRING LIGHT SOUTHWESTERLY
WINDS AROUND HIGH PRESSURE IN THE WESTERN ATLANTIC. THIS HIGH WILL
BE QUITE WEAK AND POORLY DEFINED, NOT THE STALWART BERMUDA HIGH
OFTEN SEEN IN THE WARMER MONTHS. THIS IS WHY WINDS WILL BE SO
LIGHT AND SWELL ENERGY LACKING. SOME FORECAST UNCERTAINTIES CROP
UP WEDNESDAY NIGHT INTO THURSDAY MORNING FOR OUR NORTHERN WATERS.
A BACKDOOR COLD FRONT WILL SAG SOUTHWARD CLOSE TO OR PARTIALLY
INTO THE REGION, DEPENDING ON MODEL CHOICE. CURRENT THINKING IS
THAT A NORTHEASTERLY FLOW MAY BRIEFLY AFFECT NORTHERN ZONES BUT
THIS BOUNDARY WILL RETREAT BACK NORTHWARD ON THURSDAY. A RETURN TO
LIGHT SOUTH TO SOUTHWESTERLY FLOW EXPECTED AS SEAS REMAIN MINIMAL.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 300 AM TUESDAY...FRIDAY BRINGS A CONTINUATION OF THE QUIET
CONDITIONS SEEN THROUGH MOST OF THE SHORT TERM. THAT IS, A LIGHT S
TO SWRLY FLOW AND SEAS NO HIGHER THAN 3 FT. WE MAY ADD A FEW KNOTS
OF WIND FRIDAY NIGHT AND SW WILL BECOME MORE LIKELY THAN S DUE TO
A COLD FRONT APPROACHING FROM THE NW. FROPA ITSELF MAY BE A LITTLE
LAZY ON SATURDAY AS THE BOUNDARY DECELERATES AND CHANGES
ORIENTATION TO A MORE WEST-TO-EAST NATURE AS IT TRIES TO ALIGN
WITH THE FLOW ALOFT. EVENTUALLY A NEERLY FLOW WILL OVERSPREAD THE
WATERS ON SATURDAY. THE CHANGE IN DIRECTION MAY SHORTEN THE
DOMINANT PERIOD BUT ANY UPTICK IN DOMINANT WAVE HEIGHT SHOULD BE
VERY MINOR.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MBB
NEAR TERM...RJD/TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
243 PM EDT TUE APR 7 2015
.SYNOPSIS...
A WARM AND MOIST SOUTH TO SOUTHWEST WIND FLOW WILL BRING ROUNDS OF
SHOWERS AND THUNDERSTORMS THROUGHOUT THE WEEK. COLD FRONT CROSSES AT
THE END OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
LOTS OF CONVECTION TO OUR WEST...WITH ONLY LINGERING MASS ACROSS THE
NORTHERN MOUNTAINS. TO OUR WEST...HAVE AREA BETWEEN KHTS AND
KLEX...MOVING SOUTHEAST ALONG A WEAK SURFACE BOUNDARY. THIS
CONVECTION WILL MOVE ACROSS THE SOUTHERN CWA LATE THIS AFTERNOON
INTO THIS EVENING. FARTHER WEST...IN SOUTHERN INDIANA HAVE
ANOTHER COMPLEX MOVING EAST. NAM/HRRR AND SOME WRF RUNS SHOW A MCV
WITH THIS MOVING ACROSS SOUTHERN CWA TONIGHT. RAP IS A BIT FARTHER
NORTH. AS A SURFACE LOW MOVES THROUGH MISSOURI TONIGHT...EXPECT
THE SURFACE BOUNDARY TO SLOWLY MOVE NORTH CROSSING SOUTHERN CWA
DURING THE EARLY MORNING. WITH A FAIRLY WET GROUND IN PLACE ACROSS
SOUTHERN CWA AFTER HEAVY RAIN LATE LAST WEEK...AND ANTICIPATING
ANOTHER COUPLE ROUNDS OF AT LEAST MODERATE RAIN TONIGHT...WITH GO
WITH A FLASH FLOOD WATCH ALONG AND SOUTH OF I-64. BEST CASE
SCENARIO IS THE HEAVIEST RAIN STICKS CLOSER TO THE INFLOW AND
REMAINS MAINLY SOUTH OF CWA...WITH JUST A PERIOD OF LIGHT TO
MODERATE RAIN WITH THE REMNANTS OF THE MCV. WORST CASE WOULD BE IF
EACH WAVE CROSSES THROUGH THE SAME AREA OF SOUTHERN CWA.
EXPECT A BREAK IN PRECIP...ALTHOUGH CANNOT RULE OUT AN ISOLATED
SHOWER...THROUGH MUCH OF WEDNESDAY MORNING. HAVE ANOTHER AREA OF
LIKELY POPS MOVING FROM WEST TO EAST ACROSS CWA WEDNESDAY AFTERNOON
AS A SHORTWAVE TROUGH MOVES OVER.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
MODELS ARE CLOSER TO AGREEMENT...ON LIFTING A SURFACE BOUNDARY AND
UPPER IMPULSE NORTH ACROSS THE AREA WEDNESDAY NIGHT...FOLLOWED BY A
COLD FRONT LATE THURSDAY NIGHT AND FRIDAY. WITH MOIST AND UNSTABLE
AIR IN PLACE...THESE TWO FEATURES WILL BE THE FOCUS FOR SHOWERS AND
THUNDERSTORMS...ESPECIALLY THE COLD FRONT. IN BETWEEN...IN THE WARM
SECTOR ON THURSDAY...THERE COULD BE A SHOWER OR THUNDERSTORM
ESPECIALLY IN THE AFTERNOON WITH HEATING. TIMING OF COLD FRONT HAS
IT REACHING THE OHIO RIVER AROUND DAWN FRIDAY...THEN PROGRESSING
ACROSS THE REMAINDER OF AREA DURING FRIDAY. WITH GOOD UPPER SUPPORT
AND PLENTY OF WARM AND MOIST UNSTABLE AIR...A BAND OF ORGANIZED
SHOWERS AND THUNDERSTORMS CAN BE EXPECTED ALONG AND AHEAD OF THE
COLD FRONT. WILL HAVE TO WATCH FOR WATER PROBLEMS AND STRONG STORMS
IN THIS TIME FRAME. UPON COLD FRONT PASSAGE FRIDAY...EXPECT
IMPROVEMENT FROM THE WEST. TEMPERATURE RANGES THIS PERIOD WILL BE
LOWERED SOMEWHAT BY THE CLOUDS AND SHOWERS...BUT THURSDAY MAY BE
WARMER THAN FORECAST IF SUNSHINE MAKES A DETERMINED APPEARANCE IN
THE WARM SECTOR. IN ANY CASE...NO EXTREMES IN TEMPERATURE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
MODELS ARE QUICKER WITH THE COLD FRONTAL PASSAGE ON FRIDAY LEAVING
FRIDAY NIGHT MOSTLY DRY. THE OUTLIER IS THE ECMWF WHICH LAGS ABOUT 6
HOURS IN ITS QPF FIELD. WENT WITH THE CONSENSUS OF MODELS WITH A
FASTER SOLUTIONS.
HIGH PRESSURE BRINGS WIDESPREAD DRY WEATHER FRIDAY NIGHT THROUGH THE
WEEKEND. ANOTHER UPPER WAVE APPROACHES MONDAY BRINGING BACK CHANCES
FOR PCPN ACROSS THE AREA.
TEMPERATURES EXPECTED TO BE WARM REACHING THE UPPER 70S THROUGH THE
PERIOD...EXCEPT FOR A SLIGHT COOL DOWN BEHIND THE COLD FRONT
SATURDAY...GENERALLY IN THE MID TO UPPER 60S. WENT CLOSE TO WPC
GUIDANCE WITH FEW TWEAKS THROUGH THE PERIOD.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
MESSY SITUATION WITH SHOWERS AND SOME THUNDERSTORMS DRIFTING
MAINLY EASTWARD ACROSS CWA. SEVERAL COMPLEXES TO OUR WEST WILL
TRY TO MOVE EAST...BUT MAY ALSO BE SHUNTED SOUTH ALONG A
BOUNDARY...CREATING A GOOD DEAL OF UNCERTAINTY. HAVE SOME MVFR
AND VCTS TRYING TO TIME THESE...BUT COULD BE OFF A BIT AND WOULD
NOT BE SURPRISED TO GET PERIODS OF IFR IN HEAVIER RAIN. BEST
CHANCE OF SHOWERS/STORMS THIS EVENING AND TONIGHT WILL BE ACROSS
THE SOUTH. ALSO PUT IN SOME MVFR FOG BEHIND TONIGHTS BATCH OF
SHOWERS...AGAIN MAINLY ACROSS THE SOUTH.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY...
FORECAST CONFIDENCE: LOW.
ALTERNATE SCENARIOS: TIMING OF SHOWERS AND THUNDERSTORMS COULD VARY.
FOG COULD FORM IN AREAS RECEIVING RAINFALL TUESDAY NIGHT.
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 M H H
HTS CONSISTENCY M H M H H H H H M M M M
BKW CONSISTENCY H H H H H M H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY M M M M M M M M M H M M
CKB CONSISTENCY H H H H H M H M M M M M
AFTER 18Z WEDNESDAY...
BRIEF IFR POSSIBLE IN SHOWERS AND/OR THUNDERSTORMS THROUGH FRIDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR WVZ005-006-
013>015-024>026-033>036.
OH...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR OHZ087.
KY...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR KYZ101>103-105.
VA...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR VAZ003-004.
&&
$$
SYNOPSIS...ARJ/JMV/MZ
NEAR TERM...MZ
SHORT TERM...JMV
LONG TERM...ARJ
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
233 PM EDT TUE APR 7 2015
.SYNOPSIS...
A WARM AND MOIST SOUTH TO SOUTHWEST WIND FLOW WILL BRING ROUNDS OF
SHOWERS AND THUNDERSTORMS THROUGHOUT THE WEEK. COLD FRONT CROSSES AT
THE END OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
LOTS OF CONVECTION TO OUR WEST...WITH ONLY LINGERING MASS ACROSS THE
NORTHERN MOUNTAINS. TO OUR WEST...HAVE AREA BETWEEN KHTS AND
KLEX...MOVING SOUTHEAST ALONG A WEAK SURFACE BOUNDARY. THIS
CONVECTION WILL MOVE ACROSS THE SOUTHERN CWA LATE THIS AFTERNOON
INTO THIS EVENING. FARTHER WEST...IN SOUTHERN INDIANA HAVE
ANOTHER COMPLEX MOVING EAST. NAM/HRRR AND SOME WRF RUNS SHOW A MCV
WITH THIS MOVING ACROSS SOUTHERN CWA TONIGHT. RAP IS A BIT FARTHER
NORTH. AS A SURFACE LOW MOVES THROUGH MISSOURI TONIGHT...EXPECT
THE SURFACE BOUNDARY TO SLOWLY MOVE NORTH CROSSING SOUTHERN CWA
DURING THE EARLY MORNING. WITH A FAIRLY WET GROUND IN PLACE ACROSS
SOUTHERN CWA AFTER HEAVY RAIN LATE LAST WEEK...AND ANTICIPATING
ANOTHER COUPLE ROUNDS OF AT LEAST MODERATE RAIN TONIGHT...WITH GO
WITH A FLASH FLOOD WATCH ALONG AND SOUTH OF I-64. BEST CASE
SCENARIO IS THE HEAVIEST RAIN STICKS CLOSER TO THE INFLOW AND
REMAINS MAINLY SOUTH OF CWA...WITH JUST A PERIOD OF LIGHT TO
MODERATE RAIN WITH THE REMNANTS OF THE MCV. WORST CASE WOULD BE IF
EACH WAVE CROSSES THROUGH THE SAME AREA OF SOUTHERN CWA.
EXPECT A BREAK IN PRECIP...ALTHOUGH CANNOT RULE OUT AN ISOLATED
SHOWER...THROUGH MUCH OF WEDNESDAY MORNING. HAVE ANOTHER AREA OF
LIKELY POPS MOVING FROM WEST TO EAST ACROSS CWA WEDNESDAY AFTERNOON
AS A SHORTWAVE TROUGH MOVES OVER.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
STILL TRYING TO HONE IN ON WHICH PERIODS ARE MOST ACTIVE IN THIS
UNSETTLED WEEK. THE FIRST IMPULSE WITH MOST AGREEMENT IS WEDNESDAY
MORNING ACROSS SE OH AND N WV WITH A MORE ROBUST ONE SLATED FOR
WEDNESDAY AFTERNOON ACROSS MUCH OF THE AREA. A BREAK WEDNESDAY
EVENING BEFORE CONVECTION GETS GOING ONCE AGAIN...THIS TIME ALONG A
NEW WARM FRONTAL BOUNDARY WHICH WILL SLIDE OFF TO N THURSDAY
MORNING. ATTENTION THEN TRIES TO FOCUS MORE ALONG DEVELOPING LOW
PRESSURE AND AMPLIFYING UPPER TROF ACROSS THE MIDWEST WHICH MAY
ALLOW FOR A BRIEF RESPITE FROM THE MORE WIDESPREAD CONVECTION...SAVE
FOR PERHAPS SE OH. THUS THURSDAY MAY BE OUR WARMEST THIS WEEK. TREND
IS FOR A MORE AMPLIFIED SYNOPTIC PATTERN WITH THE UPPER TROF...THUS
A FASTER FROPA...NOW SLATED FOR FRIDAY WITH ANOTHER ROUND OF
CONVECTION. THINGS DRY OUT FRIDAY NIGHT WITH THE WEEKEND SHAPING UP
TO BE RATHER NICE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
MODELS ARE QUICKER WITH THE COLD FRONTAL PASSAGE ON FRIDAY LEAVING
FRIDAY NIGHT MOSTLY DRY. THE OUTLIER IS THE ECMWF WHICH LAGS ABOUT 6
HOURS IN ITS QPF FIELD. WENT WITH THE CONSENSUS OF MODELS WITH A
FASTER SOLUTIONS.
HIGH PRESSURE BRINGS WIDESPREAD DRY WEATHER FRIDAY NIGHT THROUGH THE
WEEKEND. ANOTHER UPPER WAVE APPROACHES MONDAY BRINGING BACK CHANCES
FOR PCPN ACROSS THE AREA.
TEMPERATURES EXPECTED TO BE WARM REACHING THE UPPER 70S THROUGH THE
PERIOD...EXCEPT FOR A SLIGHT COOL DOWN BEHIND THE COLD FRONT
SATURDAY...GENERALLY IN THE MID TO UPPER 60S. WENT CLOSE TO WPC
GUIDANCE WITH FEW TWEAKS THROUGH THE PERIOD.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
MESSY SITUATION WITH SHOWERS AND SOME THUNDERSTORMS DRIFTING
MAINLY EASTWARD ACROSS CWA. SEVERAL COMPLEXES TO OUR WEST WILL
TRY TO MOVE EAST...BUT MAY ALSO BE SHUNTED SOUTH ALONG A
BOUNDARY...CREATING A GOOD DEAL OF UNCERTAINTY. HAVE SOME MVFR
AND VCTS TRYING TO TIME THESE...BUT COULD BE OFF A BIT AND WOULD
NOT BE SURPRISED TO GET PERIODS OF IFR IN HEAVIER RAIN. BEST
CHANCE OF SHOWERS/STORMS THIS EVENING AND TONIGHT WILL BE ACROSS
THE SOUTH. ALSO PUT IN SOME MVFR FOG BEHIND TONIGHTS BATCH OF
SHOWERS...AGAIN MAINLY ACROSS THE SOUTH.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY...
FORECAST CONFIDENCE: LOW.
ALTERNATE SCENARIOS: TIMING OF SHOWERS AND THUNDERSTORMS COULD VARY.
FOG COULD FORM IN AREAS RECEIVING RAINFALL TUESDAY NIGHT.
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 M H H
HTS CONSISTENCY M H M H H H H H M M M M
BKW CONSISTENCY H H H H H M H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY M M M M M M M M M H M M
CKB CONSISTENCY H H H H H M H M M M M M
AFTER 18Z WEDNESDAY...
BRIEF IFR POSSIBLE IN SHOWERS AND/OR THUNDERSTORMS THROUGH FRIDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR WVZ005-006-
013>015-024>026-033>036.
OH...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR OHZ087.
KY...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR KYZ101>103-105.
VA...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR VAZ003-004.
&&
$$
SYNOPSIS...ARJ/MZ/30
NEAR TERM...MZ
SHORT TERM...30
LONG TERM...ARJ
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS TULSA OK
322 PM CDT TUE APR 7 2015
.DISCUSSION...
A WEAK FRONTAL BOUNDARY EXTENDS FROM WEST OF KANSAS CITY INTO NW
OKLAHOMA THIS AFTERNOON WITH A VERY UNSTABLE BUT STRONGLY CAPPED
AIRMASS RESIDING OVER EASTERN OK AND NORTHWEST AR. TEMPS ALONG AND
SE OF THE FRONT HAVE WARMED INTO THE MID 80S TO NEAR 90...AND ALSO
A SUBTLE OUTFLOW BOUNDARY FROM EARLIER STORMS PUSHING THROUGH SW
MISSOURI AT THIS TIME. NO SIGNIFICANT UPPER AIR FORCING AT THIS
POINT...BUT ISOLATED STORMS STILL MAY DEVELOP NEAR THE SFC FRONT
AND OUTFLOW BOUNDARY LATER THIS AFTERNOON OR EARLY THIS EVENING
AS HRRR AND TO A LESSER EXTENT OUR LOCALLY RUN 5KM WRF CONTINUE TO
INDICATE. GIVEN THE AMOUNT OF AVAILABLE CAPE AND AT LEAST MODERATE
SHEAR ANY STORMS COULD BECOME SEVERE SHOULD UPDRAFTS BE
SUSTAINED... LARGE HAIL AND WINDS THE MAIN THREATS. CAP WILL
REMAIN WITH US FOR THE MOST PART THROUGH TONIGHT WITH ONLY A
LIMITED CHANCE OF STORMS NEAR KANSAS AND MISSOURI BORDERS.
UNSTABLE AND CAPPED ENVIRONMENT REMAINS WITH US WEDNESDAY...
HOWEVER WITH UPPER LOW CURRENTLY OFF THE CALIFORNIA COAST MOVING
INTO THE CENTRAL ROCKIES DURING THE DAY...MID LEVEL HEIGHT FALLS
AND A POTENTIAL LEAD SHORT WAVE/ JET STREAK SHOULD HELP ERODE THE
CAP ENOUGH FOR SOME STORMS TO DEVELOP ALONG THE DRY LINE FROM
CENTRAL KS INTO NORTHERN OK. MOST LIKELY TIME WOULD BE 21-00Z
HOWEVER EARLIER RUNS OF THE NAM HAVE SHOWN SOME EARLIER
DEVELOPMENT THAN THAT. WIND PROFILES SUGGEST THAT ONCE A STORM
DEVELOPS IT WILL QUICKLY BECOME SUPERCELLULAR AND POSE A THREAT
FOR VERY LARGE GAIL AND DAMAGING WINDS...AND SOME DEGREE OF
TORNADO POTENTIAL. OVERALL STORM COVERAGE IS EXPECTED TO REMAIN
FAIRLY LIMITED THROUGH WED NIGHT DUE TO PERSISTENT CAP ISSUES.
MAIN UPPER SYSTEM CONTINUES TO PROGRESS EAST THURSDAY WITH A COLD
FRONT OVERTAKING THE DRY LINE AND LIKELY PUSHING THROUGH PARTS OF
NE OKLAHOMA BY EARLY AFTERNOON. CONTINUED MOIST AND VERY UNSTABLE
AHEAD OF THE FRONT WITH MORE WIDESPREAD THUNDERSTORMS LIKELY THU
AFTERNOON AND EVENING MAINLY OVER SOUTHEAST OK AND NORTHWEST AR.
SHEAR PROFILES SUGGEST A MORE LINEAR STORM MODE AT THIS TIME.
STORMS WILL END THU EVENING WITH A COOLER AND STABLE AIRMASS
SETTLING OVER THE AREA FRIDAY.
ANOTHER UPPER LEVEL SYSTEM WILL MOVE IN FROM THE WEST BY THIS
WEEKEND AND WITH THE PRESENCE OF A SFC BOUNDARY IN THE AREA...
THUNDERSTORM CHANCES WILL RETURN BY SATURDAY AND CONTINUE INTO
EARLY NEXT WEEK. GENERAL CONSENSUS IS THIS UPPER LOW WILL
ULTIMATELY TACK A MUCH MORE SOUTHERLY TRACK...ANY SEVERE WEATHER
THREATS DURING THIS TIME REMAIN EXTREMELY UNCERTAIN.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 68 84 68 78 / 10 40 30 40
FSM 65 83 66 77 / 10 20 30 70
MLC 68 80 68 77 / 10 20 20 40
BVO 66 84 65 77 / 20 50 30 30
FYV 64 79 64 73 / 20 20 30 60
BYV 64 80 64 73 / 20 20 30 60
MKO 66 81 66 77 / 10 20 30 50
MIO 66 81 66 75 / 20 30 40 40
F10 67 83 67 78 / 10 20 20 40
HHW 65 79 66 77 / 10 10 30 60
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...06
LONG TERM....14
AREA FORECAST DISCUSSION
NWS PORTLAND
224 PM PDT TUE APR 7 2015
.SYNOPSIS...A LOW PRES MOVING INTO NORTHERN CALIFORNIA WILL TRACK
EAST INTO NORTHERN NV LATE TONIGHT AND WEDNESDAY. ANOTHER WEAK TROUGH
OF LOW PRES ALOFT WILL MOVE S OVER EASTERN WA AND OREGON WED AS A
SURFACE RIDGE OF HIGH PRES STRENGTHENS ALONG THE COAST. THE HIGH WILL
MOVE INLAND WED NIGHT AND THU. THE NEXT PACIFIC FRONTAL SYSTEM IS
EXPECTED TO MOVE DOWN FROM THE GULF OF AK AND PUSH INLAND FRI AND FRI
NIGHT FOR MORE LOWLAND RAIN AND CASCADE SNOW FOR THE WEEKEND.
&&
.SHORT TERM...A VERTICALLY STACKED UPPER LOW JUST MAKING LANDFALL ON
THE NORTH CALIFORNIA COAST THIS AFTERNOON AND CONTINUES TO MOVE
SLOWLY EAST-SOUTHEAST INTO NORTHERN CALIFORNIA. THE FRONT FROM LAST
NIGHT CONTINUES TO DISSIPATE OVER THE NORTHERN ZONES. THE NEXT FRONT
IS ROTATING AROUND THE SE QUADRANT OF THE LOW IN NRN CALIFORNIA. THE
FRONT LOOKS LIKE IT WILL SWING INTO THE CWA AS A DEFORMATION ZONE
AND STALL SOMEWHERE NEAR OVER THE SE ZONES. THE CENTRAL OREGON
CASCADES WILL PROBABLY RECEIVE THE MOST PCPN. THE GFS AND ECMWF
HOLD THE HIGHER PCPN AMOUNTS OVER THE CASCADES OF LINN AND LANE
COUNTIES. HOWEVER THIS MORNING RUNS OF THE HRRR AND NAM HAVE
EXPANDED THE HIGH PCPN AMOUNTS CLOSER TO MT. HOOD. IN LIGHT OF THIS
HAVE RAISED QPF FURTHER NORTH ALONG THE CASCADES FOR TONIGHT.
SNOW LEVELS ARE HOVERING AROUND 4500 FEET AND WITH EXPECTED PCPN WILL
CONTINUE WITH THE WINTER WEATHER ADVISORY FOR SNOW. THE GREATEST
IMPACT SHOULD BE FOR CASCADES PASSES FROM AROUND MT. JEFFERSON TO
WILLAMETTE PASS. SNOWFALL RATES WILL BE ON THE DECREASE EARLY WED
MORNING AS THE LOW DEPARTS FURTHER TO THE EAST.
MOST OF THE PRECIPITATION ASSOCIATED WITH THE UPPER LOW IS EXPECTED
TO TAPER OFF LATE TONIGHT AS THE LOW MOVES OFF TO THE E...BUT
ANOTHER TROUGH COMING DOWN FROM THE N WILL BRING A LESSER THREAT FOR
SHOWERS GOING WED AFTERNOON AND EVENING. AN UNSTABLE LAYER IN THE
LOW TO MID LEVELS WED AFTERNOON AS SEEN IN MODEL SOUNDINGS AT 00Z
THU INDICATES MARGINALLY UNSTABLE LAYER DEEP ENOUGH TO SUPPPORT A
SLIGHT CHANCE FOR THUNDER OVER THE CASCADES WED AFTERNOON. WILL ALSO
CONTINUE WITH A SLIGHT CHANCE FOR SHOWERS AGAIN THU AFTERNOON OVER
THE CASCADES AS THE WEAK TROUGH REMAINS OVER THE AREA IN AT LEAST
SOME MODELS. OTHERWISE RISING HEIGHTS SUGGESTS A WARMER DAY FOR THU
AND FRI. /MH
LONG TERM...FRIDAY NIGHT THROUGH MONDAY...RECENT MODEL RUNS HAVE
SPED UP THE TIMING OF THE WEEKEND FRONT...AND SEEM TO BE SETTLING ON
RAIN AND MOUNTAIN SNOW RETURNING TO THE PACIFIC NORTHWEST FRIDAY
NIGHT.AN UPPER LEVEL TROUGH WILL MAINTAIN SHOWERS THROUGH THE
WEEKEND...ALTHOUGH MOST OF THE SHOWERS WILL BE OVER THE HIGHER
TERRAIN SUNDAY. SNOW LEVELS SHOULD BE AROUND 4000 FEET BEHIND THE
FRONT...LATE FRIDAY NIGHT AND THEN GRADUALLY LOWER THROUGH THE
WEEKEND TO AROUND 2500 FEET. TJ
&&
.AVIATION...A WEAK LOW PRESSURE OFF THE CENTRAL OREGON COAST WILL
PUSH ASHORE NEAR THE CALIFORNIA/OREGON STATE LINE SHORTLY. THIS
SHOULD RESULT IN MAINLY VFR CONDITIONS WITH OCCASIONAL LIGHT RAIN
SHOWERS AND MVFR CONDITIONS INTO THE OVERNIGHT HOURS. A BAND OF
HEAVIER PRECIPITATION IS EXPECTED TO FORM OVER THE CENTRAL OREGON
CASCADES AND MAY ALSO MOVE CLOSE ENOUGH TO KSLE AND KEUG TO BRING
MVFR CONDITIONS TO THESE TERMINALS AFTER 00Z WEDNESDAY.
KPDX AND APPROACHES...EXPECT PRIMARILY VFR CONDITIONS THROUGH 00Z
THURSDAY. COULD SEE SOME MVFR CIGS OR VIS AROUND SUNRISE
THURSDAY...BUT VFR CONDITIONS WOULD RETURN BY LATE MORNING. BOWEN
&&
.MARINE...A WEAK LOW PRESSURE SYSTEM WILL COME ONSHORE SHORTLY
NEAR THE OREGON/CALIFORNIA BORDER. AS THE LOW MOVES SOUTH AND OUT
OF THE LOCAL AREA...WINDS WILL CONTINUE TO WEAKEN THIS EVENING.
BUILDING HIGH PRESSURE OVER THE WATERS SHOULD THEN BRING TRANQUIL
WIND AND SEAS THROUGH THURSDAY NIGHT.
A QUICK MOVING FRONT WILL LIKELY BRING A BURST OF 25 TO 35 KT
SOUTHERLY
WIND GUSTS ON FRIDAY. A LARGE FETCH OF GUSTY 25 KT WESTERLY WINDS
IN ITS WAKE WILL AID IN THE ARRIVAL OF A 10 TO 15 FT SWELL OVER
THE WEEKEND. BOWEN/NEUMAN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 3 AM PDT WEDNESDAY FOR CASCADES IN
LANE COUNTY-NORTHERN OREGON CASCADES.
WA...NONE.
PZ...NONE.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS MEDFORD OR
239 PM PDT TUE APR 7 2015
.DISCUSSION...THE UPPER LOW CURRENTLY OFF THE COAST IN NORTHWEST CAL
IS MOVING SOUTH. WET SNOW CONTINUES IN SISKIYOU COUNTY, BUT IT`S
BECOMING SHOWERY AND ROADS ARE WET. THE MODELS ARE IN PRETTY GOOD
AGREEMENT SHOWING A DEFORMATION ZONE OF PRECIPITATION SETTING UP
EAST OF THE CASCADES LATER THIS EVENING AND LASTING INTO WEDNESDAY
MORNING, BUT DIFFER SLIGHTLY ON THE PLACEMENT OF THE CORE OF HEAVIEST
QPF. THE LATEST HRRR SHOWS THE DEFORMATION ZONE WELL AND THE
FORECAST FOR TONIGHT WILL LEAN TOWARDS THAT SOLUTION. GIVEN THAT
THIS WILL SET UP AT NIGHT, THERE WILL BE AN OPPORTUNITY FOR SNOW TO
ACCUMULATE ON ROADS DURING THE OVERNIGHT HOURS FOR MOST AREAS EAST OF
THE CASCADES. THE CASCADES WILL ALSO GET ACCUMULATING SNOW TONIGHT,
THUS HAVE EXTENDED THE END TIME OF THE WINTER WEATHER ADVISORY UNTIL
WEDNESDAY MORNING. DETAILS CAN BE FOUND AT WSWMFR. GIVEN THE ABOVE
MENTIONED SCENARIO, HAVE INCREASED POPS...QPF AND SNOW AMOUNTS
SIGNIFICANTLY, BUT IT STILL MAY NOT BE ENOUGH. LATER SHIFTS MAY NEED
TO TAKE ANOTHER LOOK AT THIS AND ADJUST AMOUNTS HIGHER IF LATER
MODEL RUNS CONTINUE TO SHOW THE HIGHER QPF AMOUNTS.
WEDNESDAY WILL BE A TRANSITION DAY WITH THE DEFORMATION ZONE
WEAKENING IN THE MORNING. RAIN AND MOUNTAIN SNOW SHOWERS WILL
CONTINUE IN THE AFTERNOON, BUT SNOW LEVELS WILL COME UP TO AROUND
5000 FEET IN THE AFTERNOON, SO NOT EXPECTING MUCH IF ANY
ACCUMULATIONS FROM ABOUT MID MORNING WEDNESDAY ON DUE TO WARMING
ROAD TEMPERATURES AND SPOTTY PRECIPITATION.
DRY AND MILDER WEATHER FINALLY RETURNS THURSDAY AND CONTINUES INTO
THURSDAY NIGHT WITH SHORTWAVE RIDGING BUILDING INTO THE AREA. MOST
OF FRIDAY WILL BE DRY, THEN THE NEXT FRONT WILL REACH THE COAST
TOWARDS FRIDAY EVENING. THE GFS AND NAM ARE SLOWER WITH THE
ARRIVAL OF THE FRONT WHILE THE EC IS FASTER. FOR NOW WENT WITH A
BLEND BETWEEN THE TWO, BUT THE UPPER FLOW IS WEST OT NORTHWEST
WHICH NORMALLY LEADS TO QUICKER ARRIVAL TIMES OF FRONTS. -PETRUCELLI
THE ACTIVE PATTERN CONTINUES IN THE LONG TERM WITH ANOTHER FRONTAL
BOUNDARY MOVING INTO THE AREA LATE FRIDAY NIGHT INTO SATURDAY
MORNING. THE MODELS ARE IN FAIRLY GOOD AGREEMENT THROUGH THE LONG
TERM. THE EC IS A BIT FASTER TO PUSH THE FRONT INLAND ON SATURDAY
COMPARED TO THE GFS BUT BOTH MODELS HAVE IT PUSHED THROUGH THE AREA
BY LATE SATURDAY NIGHT. ZONAL FLOW WILL SET UP FOR SUNDAY AND THE
GFS IS HINTING AT SOME UPSLOPE SHOWERS CONTINUING ALONG THE CASCADES
THROUGH SUNDAY AFTERNOON. THERE MAY ALSO BE SOME LINGERING SHOWERS
FOR THE NORTHERN PORTION OF THE CWA...MAINLY FROM THE UMPQUA DIVIDE
NORTH. OTHERWISE, SUNDAY LOOKS TO BE THE DRIEST DAY, RELATIVELY,
THROUGH THE EXTENDED TERM. BY MONDAY MORNING, THE MODELS ARE
SLIGHTLY DIFFERENT IN THE TIMING AND STRENGTH OF THE NEXT SYSTEM TO
MOVE THROUGH. THE GFS IS FASTER AND DEEPER WITH THE NEXT TROUGH,
MEANING COOLER TEMPERATURES AND LOWER SNOW LEVELS COMPARED TO THE
EC...WHICH IS SLOWER BY ABOUT 12 HOURS AND NOT AS DEEP WITH THE
TROUGH. EITHER WAY, IT LOOKS LIKE UNSETTLED WEATHER WILL CONTINUE
THROUGH THE END OF THE EXTENDED TERM. MND
&&
.AVIATION...FOR THE 07/18Z TAF CYCLE...AS LOW PRESSURE MOVES
INLAND TODAY EXPECT CONTINUED SHOWER ACTIVITY OVER THE. THEN TONIGHT
SHOWERS WILL BECOME MORE CONCENTRATED FROM THE CASCADES EAST AND IN
NORTHERN CALIFORNIA. WITH THESES SHOWERS EXPECT A MIX OF MVFR AND
VFR CIGS ACROSS THE AREA TODAY WITH WIDESPREAD MOUNTAIN
OBSCURATIONS. ISOLATED IFR IS EXPECTED IN SNOW SHOWERS MAINLY NEAR
KMHS. THEN THIS EVENING THROUGH EARLY WEDNESDAY MORNING, EXPECT
MAINLY MVFR CIGS WITH AREAS OF IFR FROM THE CASCADES EAST AS SNOW
SHOWER DEVELOP. WEST OF THE CASCADES, ISOLATED TO SCATTERED SHOWERS
ARE EXPECTED WITH A MIX OF VFR AND MVFR CIGS. THEN EXPECT INCREASING
VFR LATE WEDNESDAY MORNING. /CC
&&
.MARINE...UPDATED 1100 AM PDT TUESDAY APR 07 2015...WINDS AND SEAS
WILL CONTINUE TO DIMINISH TODAY AS LOW PRESSURE MOVES INLAND. SEAS
WILL BE A MIX OF SOUTH WIND CHOP AND WESTERLY SWELL THIS MORNING.
THE SOUTHERLY WIND CHOP WILL DECREASE DURING THE DAY AND WESTERLY
SWELL WILL BECOME DOMINANT. HIGH PRESSURE WILL THEN BUILD INTO THE
WATERS TONIGHT INTO WEDNESDAY AND PERSIST THROUGH THURSDAY NIGHT.
THEN A FRONT WILL MOVE INTO THE WATERS LATE FRIDAY FROM THE
NORTHWEST. /CC
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY FROM 8 PM THIS EVENING TO 9 AM PDT
WEDNESDAY FOR ORZ029>031-624-625.
WINTER WEATHER ADVISORY UNTIL 9 AM PDT WEDNESDAY FOR
ORZ027-028-617-621-623.
CA...WINTER WEATHER ADVISORY FROM 8 PM THIS EVENING TO 9 AM PDT
WEDNESDAY FOR CAZ085-285.
PACIFIC COASTAL WATERS...NONE.
$$
AREA FORECAST DISCUSSION
NWS PORTLAND
132 PM PDT TUE APR 7 2015
.SYNOPSIS...A LOW PRES MOVING INTO NORTHERN CALIFORNIA WILL TRACK
EAST INTO NORTHERN NV LATE TONIGHT AND WEDNESDAY. ANOTHER WEAK
TROUGH OF LOW PRES ALOFT WILL MOVE INTO EASTERN WA AND OREGON WED AS
A SURFACE RIDGE OF HIGH PRES STRENGTHENS ALONG THE COAST. THE HIGH
WILL MOVE INLAND WED NIGHT AND THU. THE NEXT PACIFIC FRONTAL SYSTEM
IS EXPECTED TO MOVE DOWN FROM THE GULF OF AK AND PUSH INLAND FRI AND
FRI NIGHT FOR MORE LOWLAND RAIN AND MOUNTAIN SNOW THROUGH THE
WEEKEND.
&&
.SHORT TERM...A VERTICALLY STACKED UPPER LOW JUST MAKING LANDFALL ON
THE NORTH CALIFORNIA COAST THIS AFTERNOON AND CONTINUES TO MOVE
SLOWLY EAST-SOUTHEAST INTO NORTHERN CALIFORNIA. THE FRONT FROM LAST
NIGHT CONTINUES TO DISSIPATE OVER THE NORTHERN ZONES...ROUGHLY FROM
SALEM NORTHWARD. THE NEXT FRONT IS ROTATING AROUND THE SE QUADRANT OF
THE LOW. THE FRONT LOOKS LIKE IT WILL SWING INTO THE CWA AS A
DEFORMATION ZONE AND STALL SOMEWHERE NEAR OVER THE SE ZONES. THE
CENTRAL OREGON CASCADES WILL PROBABLY RECEIVE THE MOST PCPN. THE GFS
AND ECMWF HOLD THE HIGHER PCPN AMOUNTS OVER THE CASCADES OF LINN AND
LANE COUNTIES. HOWEVER THIS MORNING RUNS OF THE HRRR AND NAM HAVE
EXPANDED THE HIGH PCPN AMOUNTS CLOSER TO MT. HOOD. IN LIGHT OF THIS
HAVE RAISED QPF FURTHER NORTH ALONG THE CASCADES FOR TONIGHT.
SNOW LEVELS ARE HOVERING AROUND 4500 FEET AND WITH EXPECTED PCPN
WILL CONTINUE WITH THE WINTER WEATHER ADVISORY FOR SNOW TONIGHT. THE
GREATEST IMPACT WILL BE FOR CASCADES PASSES FROM AROUND MT.
JEFFERSON TO WILLAMETTE PASS. SNOW FALL RATES WILL BE ON THE
DECREASE EARLY WED MORNING AS THE LOW DEPARTS FURTHER TO THE EAST.
MOST OF THE PRECIPITATION ASSOCIATED WITH THE UPPER LOW IS EXPECTED
TO TAPER OFF LATE TONIGHT AS THE LOW MOVES OFF TO THE E...BUT
ANOTHER TROUGH COMING DOWN FROM THE N WILL BRING A LESSER THREAT FOR
SHOWERS GOING WED AFTERNOON AND EVENING. AN UNSTABLE LAYER IN THE
LOW TO MID LEVELS WED AFTERNOON AS SEEN IN MODEL SOUNDINGS AT 00Z
THU INDICATES MARGINALLY UNSTABLE LAYER DEEP ENOUGH TO SUPPORT A
SLIGHT CHANCE FOR THUNDER OVER THE CASCADES WED AFTERNOON. WILL ALSO
CONTINUE WITH A SLIGHT CHANCE FOR SHOWERS AGAIN THU AFTERNOON OVER
THE CASCADES AS THE WEAK TROUGH REMAINS OVER THE AREA IN AT LEAST
SOME MODELS. OTHERWISE RISING HEIGHTS SUGGESTS A WARMER DAY FOR THU
AND FRI. /MH
LONG TERM...FRIDAY NIGHT THROUGH MONDAY...RECENT MODEL RUNS HAVE
SPED UP THE TIMING OF THE WEEKEND FRONT...AND SEEM TO BE SETTLING ON
RAIN AND MOUNTAIN SNOW RETURNING TO THE PACIFIC NORTHWEST FRIDAY
NIGHT.AN UPPER LEVEL TROUGH WILL MAINTAIN SHOWERS THROUGH THE
WEEKEND...ALTHOUGH MOST OF THE SHOWERS WILL BE OVER THE HIGHER
TERRAIN SUNDAY. SNOW LEVELS SHOULD BE AROUND 4000 FEET BEHIND THE
FRONT...LATE FRIDAY NIGHT AND THEN GRADUALLY LOWER THROUGH THE
WEEKEND TO AROUND 2500 FEET. TJ
&&
.AVIATION...A WEAK LOW PRESSURE OFF THE CENTRAL OREGON COAST WILL
PUSH ASHORE NEAR THE CALIFORNIA/OREGON STATE LINE THIS
EVENING. THIS SHOULD RESULT IN MAINLY VFR CONDITIONS WITH OCCASIONAL
LIGHT RAIN SHOWERS MVFR CONDITIONS ALONG THE COAST...PARTICULARLY
AT KONP. IN ADDITION...WEAK NORTHERLY FLOW IN THE SOUTHERN
WILLAMETTE VALLEY WILL PRODUCE IFR AND MVFR CONDITIONS AT KEUG
THIS MORNING. A BAND OF HEAVIER PRECIPITATION IS EXPECTED TO FORM
OVER THE CENTRAL OREGON CASCADES AND MAY ALSO MOVE CLOSE ENOUGH
TO KSLE AND KEUG TO BRING MVFR CONDITIONS TO THESE TERMINALS AFTER
00Z WEDNESDAY. THERE IS SOME CHANCE THIS BAND OF PRECIP WILL MOVE
NORTH AND AFFECT THE PDX AREA TERMINALS LATE THIS AFTERNOON AND
EVENING.
KPDX AND APPROACHES...EXPECT PRIMARILY VFR CONDITIONS THROUGH 12Z
WEDNESDAY. MODELS ARE STARTING TO SHOW A BAND OF SHOWERS NEAR THE
TERMINAL LATE THIS AFTERNOON AND EVENING WHICH COULD PRODUCE MVFR
CONDITIONS FOR A NUMBER OF HOURS. BOWEN/NEUMAN
&&
.MARINE...A WEAK LOW PRESSURE SYSTEM WILL SLOWLY DRIFT SOUTHWARD
THIS MORNING AND PUSH ASHORE NEAR THE CALIFORNIA/OREGON BORDER
LATE TODAY. THIS WILL RESULT IN WEAKENING WINDS THROUGH THE
MORNING HOURS AND WINDS AT BUOY 29 ARE ALREADY DECREASING. BUILDING
HIGH PRESSURE OVER THE WATERS SHOULD THEN BRING MORE TRANQUIL WIND
AND SEAS THROUGH THURSDAY NIGHT.
A QUICK MOVING FRONT WILL LIKELY BRING A BURST OF 25 TO 35 KT
SOUTHERLY WIND GUSTS ON FRIDAY. A LARGE FETCH OF GUSTY 25 KT
WESTERLY WINDS IN ITS WAKE WILL AID IN THE ARRIVAL OF A 10 TO 15 FT
SWELL OVER THE WEEKEND.
HIGH PRESSURE LOOKS TO RETURN LATE IN THE WEEKEND BEFORE ANOTHER
SIMILAR STORM SYSTEM ARRIVES EARLY NEXT WEEK...AND POSSIBLY PUSHES
SEAS WELL ABOVE 10 FT ONCE AGAIN. BOWEN/NEUMAN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY FROM 2 PM THIS AFTERNOON TO 3 AM PDT
WEDNESDAY FOR CASCADES IN LANE COUNTY-NORTHERN OREGON
CASCADES.
WA...NONE.
PZ...NONE.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS MEDFORD OR
919 AM PDT TUE APR 7 2015
.DISCUSSION...CURRENT IR IMAGE SHOWS THE UPPER LOW STARTING TO
MOVE INLAND IN NORTHERN CAL. AHEAD OF THE LOW IS A BAND OF
MODERATE TO HEAVY PRECIPITATION ORIENTATED FROM SOUTHEAST TO
NORTHWEST INTO SISKIYOU COUNTY. MODERATE TO HEAVY SNOW HAS FALLEN
IN THE MOUNT SHASTA REGION INCLUDING MOUNT SHASTA CITY...TENNANT
AND IN WESTERN SISKYIOU COUNTY ABOVE 3000 FEET. SPOTTER REPORTS
HAVE BEEN COMING IN THIS MORNING AND THE BIG WINNER SO FAR HAS
BEEN 13.5 INCHES 6 MILES WEST OF BLACK BUTTE SUMMIT...7 INCHES AT
BLACK BUTTE SUMMIT...6 INCHES 2 MILES WEST OF WEED AND 5 INCHES
NEAR THE WEST SHORE OF IRON GATE LAKE. ROAD CAMS THIS MORNING SHOW
SNOW COVERED ROADS ALONG I-5 JUST SOUTH OF WEED TO
DUNSMUIR...HIGHWAY 89 AND HIGHWAY 97. SNOW IS EXPECTED TO CONTINUE
THIS MORNING, BUT THE MODELS SUGGEST SNOW WILL GRADUALLY DECREASE
THIS AFTERNOON. THIS ALONG WITH WARMING ROAD TEMPERATURES SHOULD
ALLOW ROADS TO BECOME WET IN THE AFTERNOON. CURRENT WINTER STORM
WARNING GOES OUT UNTIL 5 PM PDT, BUT WE COULD END THIS EARLIER IF
THERE`S ENOUGH EVIDENCE TO SUGGEST WE`LL NO LONGER HAVE ANY ROAD
SNOW CONCERNS.
THE NAM AND HRRR SHOWS PRECIPITATION INCREASING ALONG THE
CASCADES THIS AFTERNOON AND LASTING INTO THIS EVENING WITH SNOW
LEVELS HOVERING AROUND 4000 FEET, BUT COULD BRIEFLY LOWER TO 3500
FEET IN HEAVIER SHOWERS. MOST ROADS ARE WET IN THIS AREA EXCEPT
FOR CRATER LAKE AND DIAMOND LAKE, BUT SLUSH OR SNOW COVERED ROADS
ARE POSSIBLE THIS AFTERNOON AS PRECIP RATES INCREASE.
MADE A FEW ADJUSTMENTS TO THE FORECAST TODAY, BUT THE OVERALL IDEA
REMAINS THE SAME. -PETRUCELLI
&&
.AVIATION...FOR THE 07/12Z TAF CYCLE...STRONG LOW PRESSURE AND A
COLD FRONT WILL MOVE ACROSS NORTHERN CALIFORNIA THIS MORNING. THIS
WILL RESULT IN HEAVY SNOW OVER THE MOUNTAINS AND RAIN IN THE LOWER
ELEVATIONS WITH WIDESPREAD IFR CONDITIONS AND MOUNTAIN OBSCURATIONS
SPREADING WEST TO EAST ACROSS NORTHERN CALIFORNIA. IN OREGON, WEST
SIDE RAIN SHOWERS AND EAST SIDE SNOW SHOWERS WITH MVFR CIGS WILL BE
COMMON AS WILL MOUNTAIN OBSCURATIONS. DOWNSLOPING WILL LIKELY KEEP
RAIN FROM REACHING KMFR UNTIL AROUND DAWN, BUT THIS WILL ALSO RESULT
IN LOW LEVEL WIND SHEAR AT KMFR EARLY THIS MORNING. -SVEN
&&
.MARINE...UPDATED 350 AM PDT TUESDAY APR 07 2015... LOW PRESSURE AND
A COLD FRONT WILL MOVE INLAND TODAY. BOTH WINDS AND SEAS WILL
DIMINISH THIS MORNING AS LOW PRESSURE MOVES INLAND. HIGH PRESSURE
WILL THEN BUILD IN WEDNESDAY AND PERSIST THROUGH FRIDAY WITH WEAK
WINDS AND LIGHT TO MODERATE WESTERLY SWELL.
&&
.PREV DISCUSSION... /ISSUED 355 AM PDT TUE APR 7 2015/
DISCUSSION...OBSERVATIONS OVER THE PAST SEVERAL HOURS HAVE SHOWN
A STEADY RAIN ALONG THE COAST, PARTICULARLY AT BROOKINGS AND
CRESCENT CITY, AND INLAND TO THE COASTAL RANGES AND THE SISKIYOU
MOUNTAINS. THIS BAND OF HEAVIER PRECIPITATION WILL PUSH INLAND
THROUGH THIS MORNING, ALTHOUGH PROGRESSION WILL BE SLOW AS THE
SURFACE LOW WILL BEGIN TO WEAKEN AND MEANDER ABOUT A BIT BEFORE IT
FINALLY MOVES ONSHORE AND ALMOST COMPLETELY DISSIPATES.
WITH SNOW LEVELS HOVERING BETWEEN 3000 AND 4000 FEET, HEAVY SNOW
AMOUNTS ARE STILL EXPECTED OVER MANY PORTIONS OF NORTHERN
CALIFORNIA TODAY. WINTER WEATHER HEADLINES WILL CONTINUE THERE,
ALTHOUGH WITH THE LATEST MODEL SOLUTIONS SUGGESTING THE SYSTEM IS
SLOWING A BIT, HAVE EXTENDED THE WARNINGS AND ADVISORIES IN
SISKIYOU COUNTY BY AN ADDITIONAL SIX HOURS. THOSE SAME MODELS ARE
ALSO SHOWING AN AREA OF HEAVIER PRECIPITATION PUSHING NORTH ALONG
THE CASCADES OF OREGON. AS MANY OF THE HIGHER RESOLUTION MODELS,
AS WELL AS THE GFS, ARE DEPICTING THIS TREND, HAVE PUSHED QPF UP
ALONG THE CASCADES, AND CONSEQUENTIALLY, HAVE BUMPED UP SNOW
AMOUNTS AS WELL. THIS HAS RESULTED IN SNOW ACCUMULATIONS
APPROACHING 6 INCHES OVER A PERIOD OF ABOUT 12 HOURS THIS
AFTERNOON NEAR CRATER AND DIAMOND LAKES, AS WELL AS NEAR LAKE OF
THE WOODS AND MT ASHLAND, SO HAVE DECIDED TO ISSUE A WINTER
WEATHER ADVISORY TO COVER THE POSSIBLE TRAVEL DIFFICULTIES ALONG
THE CASCADE PASSES. FOR MORE INFORMATION REGARDING THIS ADVISORY
AND THE WARNING AND ADVISORIES FOR SISKIYOU COUNTY, SEE THE WINTER
WEATHER MESSAGE.
SNOW IS ALSO EXPECTED TODAY ACROSS MUCH OF THE EAST SIDE. SNOW
AMOUNTS SHOULD BE LIGHT, AND GIVEN THE WARM SURFACE TEMPERATURES,
DO NOT EXPECT SIGNIFICANT ACCUMULATIONS ON AREA ROADS. HOWEVER,
WINDS MAY RESULT IN BRIEF PERIODS OF LOWERED VISIBILITIES IN
BLOWING SNOW. THIS IS ALSO TRUE FOR THE SHASTA VALLEY TODAY, WHERE
GUSTY WINDS AND SNOW COULD RESULT IN GREATLY LOWERED VISIBILITIES
ALONG INTERSTATE 5.
THE SURFACE LOW, AND ITS ASSOCIATED TROUGH, WILL SLIDE EAST OUT
OF THE AREA LATE TONIGHT AND INTO WEDNESDAY MORNING. ISOLATED TO
SCATTERED SHOWERS ARE LIKELY TO LINGER IN THE AREA THROUGH THE
EARLY AFTERNOON, BUT MOST OF THE FORECAST AREA WILL SEE THE END OF
PRECIPITATION BY LATE MORNING. A BRIEF PERIOD OF RIDGING WILL HELP
TO BRING WARMER TEMPERATURES AND DRY CONDITIONS TO THE REGION
THURSDAY AND INTO FRIDAY, BUT ANOTHER STORM SYSTEM IS EXPECTED TO
BRING MORE RAIN AND COOLER TEMPERATURES FRIDAY AFTERNOON INTO
SATURDAY. SNOW LEVELS WITH THIS FASTER MOVING SYSTEM SHOULD REMAIN
ABOVE 4500 FEET, SO WIDESPREAD SNOW LIKE WE ARE SEEING TODAY IS
NOT EXPECTED. THE GFS AND ECMWF ARE IN GOOD AGREEMENT WITH THE
TIMING OF THE FRONTAL PASSAGE, SO HAVE BUMPED UP PRECIPITATION
CHANCES TO LIKELY FOR SATURDAY.
ANOTHER SYSTEM IS EXPECTED EARLY NEXT WEEK, MOST LIKELY MONDAY
NIGHT OR TUESDAY. THERE IS STILL A GOOD DEAL OF UNCERTAINTY
REGARDING THE DETAILS, BUT MODELS ARE IN REMARKABLY GOOD AGREEMENT
GIVEN THE TIME RANGE. GUIDANCE ALSO SUGGESTS THAT THIS SYSTEM WILL
INVOLVE A COLDER AIR MASS, SO THERE IS THE POTENTIAL FOR ANOTHER
SNOW EVENT, MUCH LIKE TODAY. STAY TUNED FOR UPDATES THROUGH THE
WEEK.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 8 PM PDT THIS EVENING FOR
ORZ027-028-617-621-623.
WINTER STORM WARNING UNTIL 5 PM PDT THIS AFTERNOON ABOVE 3000
FEET FOR FOR ORZ621.
CA...WINTER WEATHER ADVISORY UNTIL 5 PM PDT THIS AFTERNOON FOR
CAZ081-281.
WINTER STORM WARNING UNTIL 5 PM PDT THIS AFTERNOON ABOVE 3000
FEET FOR FOR CAZ080-280.
WINTER STORM WARNING UNTIL 5 PM PDT THIS AFTERNOON FOR
CAZ082-282.
WINTER STORM WARNING UNTIL 5 PM PDT THIS AFTERNOON FOR
CAZ083-284.
PACIFIC COASTAL WATERS...NONE.
$$
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
535 PM EDT TUE APR 7 2015
.SYNOPSIS...
A FRONTAL BOUNDARY DRAPED OVER CENTRAL PA WILL DRIFT SLOWLY TO
THE SOUTH TONIGHT THROUGH THURSDAY. MOIST AIR STREAMING NE ABOVE
A SHALLOW AND COOL AIRMASS DROPPING SOUTHWARD BEHIND THE FRONT
WILL BRING PERIODS OF A SHOWERS OVER THE NEXT SEVERAL DAYS. A BIT
OF LIGHT FREEZING RAIN IS EVEN POSSIBLE AT SOME HIGHER ELEVATIONS
THROUGHOUT CENTRAL AND NORTHEASTERN PA LATE WEDNESDAY NIGHT INTO
EARLY THURSDAY...AS STRENGTHENING HIGH PRESSURE BUILDING ACROSS
QUEBEC PUMPS COLD AIR SOUTH INTO THE REGION. A DEEP STORM SYSTEM
LIFTING ACROSS THE GREAT LAKES ON FRIDAY WILL BRING WARMER
CONDITIONS BACK INTO THE AREA...WITH A CHANCE OF THUNDERSTORMS.
A COLD FRONT WILL BE FOLLOWED BY COLDER TEMPERATURES FOR THE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
BULK OF THE RAIN SHOWERS PUSHING EAST OF THE SUSQ RIVER AS OF 21Z
IN ADVANCE OF WEAK MID LVL SHORTWAVE OVR THE CENTRAL PART OF THE
STATE. RADAR TRENDS AND LATEST HRRR SUGGEST THE STEADIEST RAIN
WILL EXIT THE EASTERN COUNTIES BY ARND 00Z. AT THE SFC...BACK DOOR
COLD FRONT IS PUSHING THRU SOUTHERN PA AT 21Z AND SHOULD PRESS
SOUTH OF THE MASON DIXON LINE THIS EVENING. A MOIST...EASTERLY
FLOW NORTH OF THIS BOUNDARY WILL LIKELY PRODUCE OCNL DRIZZLE
ACROSS CENTRAL PA LATER TONIGHT. IN ADDITION...UPSTREAM SHORTWAVE
OVR THE LOWER GRT LKS WILL LIFT THRU LATER TONIGHT...BRINGING SCT
SHRA. WILL CONTINUE TO CARRY LIKELY POPS EVERYWHERE TONIGHT...ALTHOUGH
AMOUNTS ARE NOT EXPECTED TO BE SUBSTANTIAL. GENERALLY A TRACE TO A
FEW HUNDRETHS IN MOST AREAS...UP TO A TENTH IN SOME LOCATIONS.
1038 MB SFC HIGH SPREADING EASTWARD FROM ONTARIO TO QUEBEC WILL
INDUCE CAD ACROSS EASTERN PA OVERNIGHT WITH COOLER LLVL TEMPS
BLEEDING SOUTHWARD INTO WEDNESDAY MORNING. READINGS BY DAWN
SHOULD RANGE FROM THE U30S OVR THE HIGH TERRAIN NORTH AND EAST OF
KIPT...TO THE M40S OVR THE SOUTHERN COUNTIES.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
COOL AND DANK CONDITIONS WILL BE THE NORM ON WEDNESDAY IN CAD
REGIME WITH PLENTY OF LLVL MOISTURE AND OVERRUNNING ZONAL FLOW
ALOFT PROMOTING LIGHT SHOWERS ESPECIALLY IN THE AFTERNOON. HIGHS
WILL RANGE THROUGH THE 40S FOR MOST...BUT AREAS ALONG THE
ALLEGHENY FRONT MAY NUDGE INTO THE WARM SECTOR WITH WESTERN WARREN
AND WESTERN SOMERSET COUNTIES REACHING INTO THE 50S AND PERHAPS
NEAR 60 ACROSS SOUTHWEST SOMERSET COUNTY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
DID NOT CHANGE POPS OR WEATHER FOR WED NIGHT...GIVEN SLIGHT
CHANCE FOR A LITTLE FREEZING DRIZZLE OR RAIN ACROSS THE NE.
LOWS NEAR HUDSON AND JAMES BAY AREA WERE ZERO TO 20 BELOW
THIS MORNING. THAT IS COLD FOR EARLY APRIL.
DETAILS BELOW...
GIVEN THE FACT THAT WE/LL HAVE A 1040 MB SFC HIGH BECOMING PARKED
ACROSS SRN QUEBEC /WHERE CURRENT TEMPS ARE IN THE SINGLE DIGITS TO
TEENS/ AND 1000 MB AGEOSTROPIC FLOW INCREASING FROM THE
NORTH-NORTHEAST /AND STAYING THERE FOR A 24-36 HOURS PERIOD/...WENT
SEVERAL DEG F BELOW MODEL TEMPS FOR WED MAXES AND WED NIGHT MINS.
EVEN MENTIONED A SLIGHT CHC FOR LIGHT FZRA ACROSS PARTS OF THE
NCENT MTNS AND WRN POCONOS LATE WED NIGHT AND EARLY THURSDAY.
THIS LLVL COLD AIR DAMMING LIKELY TO LINGER INTO THURSDAY AFT.
SOME NEW DETAIL BELOW...
WHILE TEMPS MAY NOT WARM REAL GOOD THU...AND I LEFT THEM
CLOSE TO WHAT WE HAD...WILL CONTINUE TO MONITOR. VERY TIGHT
TEMPERATURE GRADIENT AT 850 MB LATE WED EVENING ACROSS CENTRAL
NY...MINUS 4 TO PLUS 10 IN ABOUT 80 TO 100 MILE BAND.
ANYWAY...WARMER AIR WILL WORK INTO THE AREA LATE THU INTO
FRIDAY...AS LOW LEVEL WIND FIELDS INCREASE. WARMEST TEMPERATURES
MIGHT END UP BEING ACROSS WARREN COUNTY.
DID NOT UP TEMPS MUCH FOR FRIDAY...MODELS MOVE COLD FRONT ACROSS
THE AREA RATHER FAST.
SOME CHANCE OF A STRONG THUNDERSTORM ACROSS THE WEST LATER FRIDAY.
THIS BASED ON TIMING AND THE THERMAL RIDGE OVER THE BEST MOISTURE.
HAVE TO WATCH FOR SEVERE...BUT DYNAMICS LIKELY TO LIFT NE AWAY
FROM THE AREA. ALSO TIMING NOT THE BEST.
WHILE WE WILL SEE SOME SHOWERS EACH DAY THIS WEEK...NOT SEEING ANY
LARGE AMTS. THUS NOT SEEING ANY WIDESPREAD HYDRO CONCERNS AT THIS
POINT. ENJOY THE MILDER TEMPERATURES.
RATHER STRONG SMALL UPPER LEVEL TROUGH FOR LATE FRIDAY INTO SAT.
TOOK OUT SHOWERS AFTER EARLY FRIDAY EVENING. MAIN THING WAS TO
LOWER TEMPS FOR FRIDAY NIGHT INTO SAT...GIVEN AIRMASS TO THE NORTH
AND COLD ADVECTION.
WEEKEND SIMILAR TO LAST WEEKEND. BREEZY AND COOL ON SAT. WARMER
ON SUNDAY.
DID PUT SOME SHOWERS IN THE FAR WEST LATE MONDAY AND ACROSS THE
AREA ON TUE. MODELS SHOW ANOTHER COLD FRONT MOVING IN.
&&
.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
BANDS OF SCATTERED LIGHT SHOWERS CONTINUE TO STREAM EASTWARD OVER
CENTRAL PA THIS MORNING. AS A FRONT CONTINUES TO PUSH EVER SO
SLOWLY SOUTHWARD...MVFR RESTRICTIONS WILL CONTINUE TO SAG
SOUTHWARD THROUGH THE DAY. IFR CONDITIONS WILL AFFECT THE NORTHERN
MTNS AS FRONT PUSHES INTO HIGH DEWPOINT AIR. ONCE THESE IFR/MVFR
RESTRICTIONS ARRIVE IN A LOCATION...THEY WILL THEN PERSIST FOR AN
EXTENDED PERIOD AS UNSETTLED WEATHER IMPACTS THE REGION THROUGH
THE WEEK.
MARGINAL CAPE MAY BRING ISOLATED THUNDER TO THE SOUTHERN TIER OF
CENTRAL PA THROUGH THIS EVENING. WINDS WILL REMAIN LIGHT INTO
WED.
OUTLOOK...
WED...WIDESPREAD MVFR/IFR IN SHRA/PERIODS OF RA.
THU...REDUCTIONS LIKELY IN SCT SHRA.
FRI...REDUCTIONS LIKELY IN SHRA...ESPECIALLY DURING THE
AFT. CHC OF THUNDER AFT.
SAT-SUN...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...DEVOIR
LONG TERM...LAMBERT/MARTIN
AVIATION...DEVOIR/RXR