Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 02/10/15
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
1042 AM CST SUN FEB 8 2015
.UPDATE...
JUST A QUICK UPDATE TO REMOVE THE MORNING MENTION OF PATCHY FOG
AND TO ADJUST THE SKY GRIDS BASED ON CURRENT TRENDS. STILL EXPECT
THE COLD FRONT TO ENTER NORTHWEST ARKANSAS LATER THIS AFTERNOON
OR EARLY THIS EVENING...WITH CONTINUED LIGHT PRECIP CHANCES ACROSS
MUCH OF THE SE HALF OF THE STATE.
&&
.PREV DISCUSSION... /ISSUED 551 AM CST SUN FEB 8 2015/
AVIATION...08/12Z TAF CYCLE
WIDESPREAD LOW CLOUDS /MVFR CIGS/ WERE NOTED ACRS CNTRL AND SRN AR
EARLY THIS MRNG. HRRR MODEL CONTS TO HANDLE TRENDS VERY WELL...KEEPING
A MAJORITY CLOUD DECK TO THE S OF THE HIGHER TERRAIN OF W-CNTRL AND
N-CNTRL AR TODAY. COULD SEE SOME SCTD LOW CLOUDS WORK INTO NRN AR
LATER THIS MRNG...BUT VFR CONDS ARE EXPECTED THRU THE PD. MVFR
CONDS WL PREVAIL ELSEWHERE INTO THE AFTN WITH A SLOW IMPROVEMENT
THEREAFTER. A CDFNT WL DROP SWD ACRS THE FA TNGT...WITH A GRADUAL
WIND SHIFT EXPECTED. SOME LOW CLOUDS COULD DRIFT SWD INTO NRN AR...
BUT APPEARS THIS WL NOT OCCUR UNTIL JUST BEYOND THIS FCST PD. /44/
PREV DISCUSSION... /ISSUED 314 AM CST SUN FEB 8 2015/
SHORT TERM...TODAY THROUGH WEDNESDAY
MOISTURE IS STREAMING NORTH INTO THE STATE EARLY THIS
MORNING...EVIDENT IN THE LOW LEVEL STRATUS DECK DEVELOPING ACROSS THE
SERN HALF OF THE CWA. THIS WILL CONTINUE THROUGH THIS MORNING...WITH
SOME SPRINKLES AND DRIZZLE POSSIBLE. SOME PATCHY FOG MAY ALSO BE
SEEN...BUT LOW CLOUDS MAY REMAIN DOMINANT AS WINDS KEEP WIDESPREAD
FOG FROM FORMING. THESE CLOUDS WILL ALSO KEEP TEMPS FROM WARMING TOO
FAR THIS AFTERNOON...WITH HIGHS IN THE UPPER 50S TO MID 60S IN THIS
REGION OF THE STATE. FURTHER NW...SHOULD SEE LESS CLOUD COVER...AT
LEAST FOR A PORTION OF THE DAY...RESULTING IN WARMER TEMPS BY THIS
AFTERNOON. HIGHS WILL BE IN THE MID TO UPPER 60S...WITH TEMPS JUST
OVER 70 NOT OUT OF THE QUESTION ACROSS THE FAR NW. CHANCES FOR
SEEING ANY LIGHT PRECIP WILL ALSO BE LOWER IN THIS PART OF THE CWA.
LATE THIS AFTERNOON...A WEAK COLD FRONT WILL DROP SE INTO
AR...MOVING SE THROUGH THE STATE TONIGHT INTO MON MORNING. THE MAIN
IMPACTS WILL BE A WIND SHIFT TO THE NW...AND SLIGHTLY DRIER AIR
DROPPING SOUTH INTO THE STATE. SLIGHTLY COOLER TEMPS WILL ALSO BE
SEEN FOR MON...WITH HIGHS IN THE MID 50S TO MID 60S EXPECTED. COOLER
CONDITIONS WILL BE SEEN FOR TUE AS HIGH PRESSURE MOVES OVER THE CWA.
THIS HIGH WILL SHIFT EAST FOR LATE TUE INTO TUE NIGHT...WITH SRLY
FLOW RETURNING. THIS WILL WARM TEMPS SOME FOR WED...BUT A NEW COLD
FRONT WILL BE DROPPING SOUTH INTO THE STATE LATE WED. THIS FRONT MAY
BRING SOME PRECIP...BUT HAVE ONLY MENTIONED SLIGHT CHANCE POPS FOR
SOME RAIN WED AFTERNOON AND EVENING AS MOISTURE LEVELS LOOK LIMITED
ONCE AGAIN. THE MAIN COLD AIR IMPACTS BEHIND THIS FRONT WILL BE SEEN
DURING THE LONG TERM PERIOD.
LONG TERM...THURSDAY THROUGH SATURDAY
STILL NO SIG CHGS TO THE OVERALL FCST THRU THE END OF THE WEEK. A
CDFNT WL BE SHIFTING S OF AR AT THE START OF THE PD...WITH ANOTHER
ROUND OF COLDER AIR ADVECTING INTO THE REGION. THE ASSOCD HIGH PRES
RDG WL SLIDE ACRS AR THRU EARLY FRI THEN SHIFT E OF THE AREA...
ALLOWING FOR SOME MODERATION IN TEMPS.
PERSISTENT NWLY FLOW ALOFT WL BRING ANOTHER QUICK MOVG CLIPPER SYS
SEWD THRU THE AREA FRI NGT AND EARLY SAT. ONLY EXPECT SOME CLOUDS
WITH THE ASSOCD CDFNT AS LOW LVL MOISTURE WL BE NON-EXISTENT...
SO DRY CONDS WL PREVAIL.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 67 41 56 33 / 20 0 0 0
CAMDEN AR 67 46 67 39 / 20 10 0 0
HARRISON AR 72 39 56 32 / 10 0 0 0
HOT SPRINGS AR 66 46 65 38 / 20 10 0 0
LITTLE ROCK AR 66 45 62 35 / 20 10 0 0
MONTICELLO AR 67 48 63 37 / 20 10 0 0
MOUNT IDA AR 66 44 66 38 / 20 0 0 0
MOUNTAIN HOME AR 69 39 55 32 / 10 0 0 0
NEWPORT AR 66 41 56 32 / 20 10 0 0
PINE BLUFF AR 66 45 61 35 / 20 10 0 0
RUSSELLVILLE AR 68 42 64 36 / 10 0 0 0
SEARCY AR 65 42 59 33 / 20 10 0 0
STUTTGART AR 65 43 59 34 / 20 10 0 0
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
65
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
551 AM CST SUN FEB 8 2015
.AVIATION...08/12Z TAF CYCLE
WIDESPREAD LOW CLOUDS /MVFR CIGS/ WERE NOTED ACRS CNTRL AND SRN AR
EARLY THIS MRNG. HRRR MODEL CONTS TO HANDLE TRENDS VERY WELL...KEEPING
A MAJORITY CLOUD DECK TO THE S OF THE HIGHER TERRAIN OF W-CNTRL AND
N-CNTRL AR TODAY. COULD SEE SOME SCTD LOW CLOUDS WORK INTO NRN AR
LATER THIS MRNG...BUT VFR CONDS ARE EXPECTED THRU THE PD. MVFR
CONDS WL PREVAIL ELSEWHERE INTO THE AFTN WITH A SLOW IMPROVEMENT
THEREAFTER. A CDFNT WL DROP SWD ACRS THE FA TNGT...WITH A GRADUAL
WIND SHIFT EXPECTED. SOME LOW CLOUDS COULD DRIFT SWD INTO NRN AR...
BUT APPEARS THIS WL NOT OCCUR UNTIL JUST BEYOND THIS FCST PD. /44/
&&
.PREV DISCUSSION... /ISSUED 314 AM CST SUN FEB 8 2015/
SHORT TERM...TODAY THROUGH WEDNESDAY
MOISTURE IS STREAMING NORTH INTO THE STATE EARLY THIS
MORNING...EVIDENT IN THE LOW LEVEL STRATUS DECK DEVELOPING ACROSS THE
SERN HALF OF THE CWA. THIS WILL CONTINUE THROUGH THIS MORNING...WITH
SOME SPRINKLES AND DRIZZLE POSSIBLE. SOME PATCHY FOG MAY ALSO BE
SEEN...BUT LOW CLOUDS MAY REMAIN DOMINANT AS WINDS KEEP WIDESPREAD
FOG FROM FORMING. THESE CLOUDS WILL ALSO KEEP TEMPS FROM WARMING TOO
FAR THIS AFTERNOON...WITH HIGHS IN THE UPPER 50S TO MID 60S IN THIS
REGION OF THE STATE. FURTHER NW...SHOULD SEE LESS CLOUD COVER...AT
LEAST FOR A PORTION OF THE DAY...RESULTING IN WARMER TEMPS BY THIS
AFTERNOON. HIGHS WILL BE IN THE MID TO UPPER 60S...WITH TEMPS JUST
OVER 70 NOT OUT OF THE QUESTION ACROSS THE FAR NW. CHANCES FOR
SEEING ANY LIGHT PRECIP WILL ALSO BE LOWER IN THIS PART OF THE CWA.
LATE THIS AFTERNOON...A WEAK COLD FRONT WILL DROP SE INTO
AR...MOVING SE THROUGH THE STATE TONIGHT INTO MON MORNING. THE MAIN
IMPACTS WILL BE A WIND SHIFT TO THE NW...AND SLIGHTLY DRIER AIR
DROPPING SOUTH INTO THE STATE. SLIGHTLY COOLER TEMPS WILL ALSO BE
SEEN FOR MON...WITH HIGHS IN THE MID 50S TO MID 60S EXPECTED. COOLER
CONDITIONS WILL BE SEEN FOR TUE AS HIGH PRESSURE MOVES OVER THE CWA.
THIS HIGH WILL SHIFT EAST FOR LATE TUE INTO TUE NIGHT...WITH SRLY
FLOW RETURNING. THIS WILL WARM TEMPS SOME FOR WED...BUT A NEW COLD
FRONT WILL BE DROPPING SOUTH INTO THE STATE LATE WED. THIS FRONT MAY
BRING SOME PRECIP...BUT HAVE ONLY MENTIONED SLIGHT CHANCE POPS FOR
SOME RAIN WED AFTERNOON AND EVENING AS MOISTURE LEVELS LOOK LIMITED
ONCE AGAIN. THE MAIN COLD AIR IMPACTS BEHIND THIS FRONT WILL BE SEEN
DURING THE LONG TERM PERIOD.
LONG TERM...THURSDAY THROUGH SATURDAY
STILL NO SIG CHGS TO THE OVERALL FCST THRU THE END OF THE WEEK. A
CDFNT WL BE SHIFTING S OF AR AT THE START OF THE PD...WITH ANOTHER
ROUND OF COLDER AIR ADVECTING INTO THE REGION. THE ASSOCD HIGH PRES
RDG WL SLIDE ACRS AR THRU EARLY FRI THEN SHIFT E OF THE AREA...
ALLOWING FOR SOME MODERATION IN TEMPS.
PERSISTENT NWLY FLOW ALOFT WL BRING ANOTHER QUICK MOVG CLIPPER SYS
SEWD THRU THE AREA FRI NGT AND EARLY SAT. ONLY EXPECT SOME CLOUDS
WITH THE ASSOCD CDFNT AS LOW LVL MOISTURE WL BE NON-EXISTENT...
SO DRY CONDS WL PREVAIL.
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
1113 AM PST SUN FEB 8 2015
.SYNOPSIS...THUNDERSTORMS, RAIN SHOWERS AND VERY HIGH ELEVATION
LIGHT SNOW WILL CONTINUE THROUGH MONDAY MORNING AS THE LAST OF A
SERIES OF STORMS MOVES THROUGH THE AREA. HIGH PRESSURE RETURNS BY
TUESDAY PRODUCING DRY WEATHER AND PATCHY NIGHTTIME AND MORNING FOG
IN THE SAN JOAQUIN VALLEY THROUGH THE REMAINDER OF NEXT WEEK.
&&
.DISCUSSION...AN UPPER LOW CURRENTLY OFF THE NORTHERN CALIFORNIA
COASTLINE WILL CONTINUE TO LIFT QUICKLY NORTH NORTHEAST INTO THE
PACIFIC NORTHWEST THIS EVENING INTO MONDAY. THIS LOW RESULTED IN
SOUTHWEST FLOW ACROSS THE REGION...WITH RAIN SHOWERS...THUNDERSTORMS...GUSTY
SOUTHERLY WINDS...AND SNOW ABOVE 9000 FEET FORECAST FROM THIS
AFTERNOON INTO EARLY MONDAY MORNING. LIGHT RAIN IMPACTED THE WEST
SIDE OF THE VALLEY THIS MORNING WITH A FEW HUNDREDTHS OF AN INCH
IN LOS BANOS...PACHECO PASS...AND TRACE AMOUNTS IN MERCED. THE
FIRST BAND OF RAIN HAS MOVED EAST AND IS NOW IMPACTING THE
FOOTHILLS AND SIERRA NEVADA FROM MADERA COUNTY NORTHWARD.
THE SECOND ROUND OF RAIN IS APPROACHING THE WEST SIDE OF THE
VALLEY AND SHOULD MOVE INTO THE AREA WITHIN THE HOUR. RAIN WILL
SPREAD SOUTH...IMPACTING MUCH OF THE REGION BY LATER THIS
AFTERNOON. THE HIGH RES ARW AND HIGH RES NMM BOTH INDICATE THAT
RAIN WILL IMPACT MUCH OF THE REGION EXCEPT THE DESERT
LOCATIONS...HOWEVER THE LATEST RUNS OF THE HRRR INDICATE THAT THE
PRECIPITATION WILL GENERALLY STAY NORTH OF KERN COUNTY. EITHER
WAY...NOT MUCH ACCUMULATION IS EXPECTED...WITH VALLEY LOCATIONS
RECEIVING BETWEEN A TENTH AND A THIRD OF AN INCH...FOOTHILLS
SHOULD RECEIVE BETWEEN A HALF INCH AND AN INCH...WITH THE HIGHER
ELEVATIONS UPWARDS OF ONE AND A HALF INCHES.
SNOW LEVELS WITH THIS STORM WILL BE HIGH...STARTING OUT AROUND
9,500 FEET LOWING TO 9,000 FEET BY EARLY MONDAY MORNING. THE 12Z
OAKLAND SOUNDING SHOWED A FREEZING LEVEL AT 9,900 FEET.
REGARDLESS...LOCATIONS GENERALLY ABOVE 9,500 FEET COULD SEE A
QUICK 6 TO 8 INCHES OF SNOW...WITH A FEW ISOLATED AREAS IN
MAPIPOSA AND TUOLUMNE COUNTIES RECEIVING BETWEEN 10 AND 12 INCHES
OF SNOW.
AS THE UPPER LOW SHIFTS NORTH AND THE ASSOCIATED COLD FRONT MOVES
TOWARD THE REGION LATER THIS AFTERNOON...SOUTH WINDS WILL BEGIN TO
INCREASE SIGNIFICANTLY ON THE WEST SIDE OF THE VALLEY. THE HRRR
HAS BEEN HANDLING THE WINDS WELL AND SHOWS A RAPID INCREASE IN
WINDS AFTER 21Z...WITH WIND GUSTS BETWEEN 40 AND 50 MPH. THESE
WINDS WILL SUBSIDE EARLY MONDAY MORNING.
LASTLY...WITH THIS STORM THERE IS THE POTENTIAL FOR THUNDERSTORMS
EARLY THIS AFTERNOON INTO THE EVENING HOURS. CURRENTLY...LAPS
ANALYSIS IS SHOWING CAPE VALUES BETWEEN 100 AND 200 J/KG JUST TO
THE WEST OF MERCED AND FRESNO COUNTY. HOWEVER...THE HIGH RES SHORT
TERM MODELS AND THE NAM ALL INDICATE A DESTABILIZATION OF THE
ATMOSPHERE BETWEEN 21Z AND 00Z...WITH CAPE VALUES ALONG THE
WESTERN SIDE OF THE VALLEY INCREASING TO UPWARDS OF 800 J/KG. THE
STORM PREDICTION CENTER IS CALLING FOR A MARGINAL CHANCE FOR
SEVERE THUNDERSTORMS FROM FRESNO COUNTY NORTHWARD...WITH A SLIGHT
CHANCE ALONG FAR NORTHERN MERCED AND MARIPOSA COUNTIES. IF
THUNDERSTORMS DO FORM...EXPECT FREQUENT LIGHTNING...ERRATIC
WINDS...HAIL...AND BRIEF HEAVY DOWNPOURS. PLEASE CONTINUE TO
MONITOR THE FORECAST FOR THE LATEST INFORMATION.
OTHERWISE...THE UPPER LOW IS FORECAST TO OPEN UP TO AN UPPER
TROUGH EARLY MONDAY MORNING ALONG THE PACIFIC NORTHWEST COAST AND
MOVE EAST. THIS WILL ALLOW UPPER LEVEL HIGH PRESSURE TO BEGIN TO
BUILD OVER THE REGION LATE MONDAY EVENING INTO TUESDAY. THIS HIGH
PRESSURE WILL CONTINUE OVER THE AREA THROUGH NEXT
WEEKEND...RESULTING IN ABOVE NORMAL TEMPERATURES...DRY
CONDITIONS...AND PATCHY LATE NIGHT AND EARLY MORNING FOG.
&&
.AVIATION...
IN THE SAN JOAQUIN VALLEY...VFR WITH AREAS OF MVFR IN SHRA THROUGH
12Z MON. SCT THUNDERSTORMS BETWEEN 20Z SUN AND 06Z MON. LOCAL IFR IN
MIST AND FOG BETWEEN 12Z AND 18Z MON.
IN THE SOUTHERN SIERRA NEVADA AND ADJACENT FOOTHILLS...MOUNTAIN
OBSCURING IFR CONDITIONS IN CLOUDS AND PRECIPITATION THROUGH 12Z
MON. SCT THUNDERSTORMS BETWEEN 20Z SUN AND 06Z MON IN THE FOOTHILLS.
STRONG WIND GUSTS OVER 50 KT ALONG THE SOUTHERN SIERRA CREST
POSSIBLE THROUGH 12Z MON. CONDITIONS IMPROVING TO VFR AFTER 18Z MON.
IN THE TEHACHAPI MOUNTAINS...VFR THRU 22Z SUN THEN AREAS OF MOUNTAIN
OBSCURING IFR CONDITIONS IN CLOUDS AND SHOWERS THROUGH 12Z MON.
CONDITIONS IMPROVING TO VFR AFTER 18Z MON.
IN THE KERN COUNTY DESERTS...VFR CONDITIONS ARE EXPECTED FOR THE
NEXT 24 HOURS.
&&
.AIR QUALITY ISSUES...
NONE.
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS HIGH.
THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED
BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 02-08 74:1987 41:1989 53:1993 28:1891
KFAT 02-09 71:2012 45:1923 56:1987 27:1891
KFAT 02-10 75:1961 44:1894 54:1916 29:1965
KBFL 02-08 77:1917 46:1939 53:1963 23:1929
KBFL 02-09 77:2012 42:1919 58:1975 24:1929
KBFL 02-10 79:1961 47:1967 54:1973 23:1929
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH LATE TONIGHT CAZ096.
WIND ADVISORY UNTIL 4 AM PST MONDAY CAZ089-091.
&&
$$
PUBLIC...RILEY
AVN/FW...BEAN
SYNOPSIS...WP
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
650 AM PST Sun Feb 8 2015
Update
.Synopsis...
A storm system moves through the region today and tonight bringing
heavy rain, gusty winds and potentially severe afternoon/evening
thunderstorms. Snow may cause travel difficulties for Sierra
passes tonight into Monday. Lingering showers Monday then drier
and warmer conditions return Tuesday.
&&
.UPDATE DISCUSSION...
The potential for severe weather in the Valley is looking more
favorable late this afternoon and early evening. The Storm
Prediction Center has the central and southern Sacramento and
northern San Joaquin valleys in a Slight Risk for severe
thunderstorms. Latest HRRR Reflectivity projects some strong cells
developing on the east side of Valley around 4 pm behind the front.
Large hail and heavy rain are the main concerns. Models show shear
profile could be sufficient for tornado formation so we will have to
keep a close watch on things today. Main issue is if instability
levels will be high enough behind the front. Clearing skies and some
sun could provide this, if the timing is right. EK
.Discussion...
Quiet weather early this morning as a weak shortwave exits and a
much stronger and wetter system lies off the coast. Some patchy
morning fog and mist has developed, though this should lift later
this morning as the storm moves inland and clouds increase. Just a
few light showers currently showing up on radar over Shasta
County, while an area of warm sector precipitation is approaching
the coast. Southerly upslope flow could bring some scattered
showers this morning into the northern Sacramento Valley and
southern Cascades ahead of the main area of precipitation. Wind is
currently light southerly.
The upper level low off the coast will shift eastward today and
move inland tonight. Precipitation will spread from west to east
this morning, over the Coastal mountains and then across the
Valley by late morning. A strong area of diffluence will be
located over northern California by mid day. This will provide
significant lift, which coupled with a very moist plume and
instability will bring moderate to locally heavy rain for the
afternoon. The cold front looks like it will move into the Valley
and Delta around 3-4 pm, with the heaviest precipitation occurring
around that time for the Valley. Estimated Valley rainfall amounts
range from a half inch over the San Joaquin Valley to around 2 inches
over the northern Sacramento Valley. Locally higher amounts are
possible with heavy showers/thunderstorms. The mountains should see
an additional 1 to 3 inches of liquid equivalent.
Low and mid level shear with this system is impressive, and
strong thunderstorms could form this afternoon, especially with
and behind the cold front. There is the potential for hail and
severe weather, with strong low level southerly flow developing
late this afternoon. Models indicate shear levels could reach
levels which local research has correlated with tornado
development in the past, so there is some potential for tornadic
activity. A limiting factor is the cold front may push through too
late in the afternoon for clearing and further destabilization of
the atmosphere by solar heating. So strong instability may be
lacking.
There should be enough instability to continue chances of
thunderstorms through the evening and overnight as cold air aloft
moves across the region.
Heavier precipitation should reach the Sierra around noon-1 pm.
Good southwest upslope flow will enhance precipitation over the
Sierra and squeeze out much of the available moisture. Snow levels
initially will be above pass levels with moderate to heavy rain, but
will drop to around 7000 feet later afternoon and early evening as
colder air moves through. Heavy convection showers may also bring
the snow levels down some locally at times. Travel disruptions are
possible at pass levels tonight and into Monday, as snow levels
drop to around 6000 feet. The best timing for snow accumulation is
expected to be in the morning hours Monday, when precipitation is
still fairly strong and cooler air is moving through. Higher peaks
could see more than a foot of snow, while pass levels could see
around 6 to 10 inches.
A Flash Flood Watch remains in effect through early Monday for
the Rim Fire Burn area, where debris flows and stream rises are
possible from the heavy rain.
The southerly surface gradient increases by this afternoon with
winds gusting up to 45 mph across the Valley. Strongest winds will
likely accompany the frontal passage. Winds will gradually
decrease this evening. A Wind Advisory is in effect between noon
and midnight.
A chance of showers and thunderstorms will linger across the
region into Monday as a final short-wave in this series moves
through, then drier weather returns Tuesday with much warmer
temperatures. Temperatures rise to well above normal levels by
Wednesday as upper level ridging builds. North to east winds
develop and will begin to dry things out. Morning fog is possible,
especially in sheltered areas on the east side of the Valley and
over the Delta.
&&
A chance of showers and thunderstorms will linger across the
region into Monday as a final short-wave in this series moves
through, then drier northerly flow returns for Tuesday.
&&
.Extended Discussion (Thursday through Sunday)
Medium range models similar in showing Rex block pattern over the
west coast through the extended period with strong high pressure
over the southwest U.S. and a low pressure system in the vicinity of
Baja. This will result in dry weather with above normal
temperatures for Norcal. Weak pressure gradients under the upper
ridge will bring generally light north and east winds from the
middle to the end of next week.
&&
.Aviation...
Mainly IFR ceilings with areas of fog in the central valley. LIFR
visibility this morning in the delta. Widespread IFR aft 18z thru
tonight as frontal system brings rain and continues low ceilings.
Increasing winds after 18z reaching sustained 20 knots plus with
gusts to over 40 knots valley and over 60 knots mountains.
Isolated thunderstorms possible most areas after about 20z.
Thunderstorm threat decreasing after 03z tonight.
&&
.STO Watches/Warnings/Advisories...
winter weather advisory from 4 pm this afternoon to 4 pm pst
monday above 6500 feet in the west slope northern sierra nevada.
flash flood watch through late tonight motherlode...west slope
northern sierra nevada.
wind advisory from noon today to midnight pst tonight carquinez
strait and delta...central sacramento valley...motherlode...
northeast foothills/sacramento valley...northern sacramento
valley...northern san joaquin valley...southern sacramento
valley.
&&
$$
AREA FORECAST DISCUSSION
NWS ALBANY NY
235 AM EST SUN FEB 8 2015
.SYNOPSIS...
OUR REGION WILL HAVE A PROLONGED PERIOD OF SNOW FOR THE NEXT
SEVERAL DAYS. LOW PRESSURE WILL MOVE SLOWLY FROM THE LOWER GREAT
LAKES TODAY TO THE DELMARVA COAST LATE MONDAY AFTERNOON...THEN
SLOWLY MOVE OFFSHORE TUESDAY. HIGH PRESSURE WILL BRIEFLY CREST
INTO THE REGION TUESDAY NIGHT. A CLIPPER LOW PRESSURE SYSTEM WILL
DIVE SOUTHEAST FROM THE GREAT LAKES WED NIGHT AND THURSDAY
BRINGING MORE SNOW TO THE REGION...AND USHERING IN FRIGID AIR TO
END THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
A WINTER STORM STORM WARNING REMAINS IN EFFECT FOR THE ENTIRE REGION
THROUGH MONDAY NIGHT.
AS OF 235 AM EST...A LONG DURATION PERIOD OF LIGHT TO MODERATE
SNOW IS ONGOING AND IS EXPECTED TO CONTINUE THROUGH THE ENTIRE
NEAR TERM PERIOD. LIGHT SNOW HAS BEEN ONGOING SO FAR THIS MORNING
THANKS TO FAVORABLE UPPER LEVEL JET DYNAMICS. AT THE SURFACE...AN
ARCTIC COLD FRONT EXTENDS ACROSS SOUTHERN PARTS OF THE
REGION...PROVIDING SOME LOW LEVEL CONVERGENCE. THIS BOUNDARY IS
EVIDENT ON SFC OBSERVATIONS...WHERE TEMPS HAVE FALLEN INTO THE
TEENS NORTH OF THE BOUNDARY...BUT REMAIN IN THE UPPER 20S TO NEAR
30 ACROSS THE MID HUDSON VALLEY AND NORTHWESTERN CONNECTICUT.
THE LATEST 05Z 3KM HRRR SHOWS THE ONGOING LIGHT SNOW ACTIVITY MAY
START TO WANE BY AROUND DAYBREAK OR SO. BY THIS TIME...UP TO AN
ADDITIONAL INCH OR TWO OF SNOW IS POSSIBLE...MAINLY FOR AREAS
BETWEEN INTERSTATE 90 AND THE SOUTHERN ADIRONDACKS...WHERE THE BEST
RADAR RETURNS HAVE BEEN ONGOING SO FAR OVERNIGHT.
DURING THE MORNING HOURS...THE LOW LEVEL SFC BOUNDARY WILL CONTINUE
TO DROP SOUTHWARD TOWARDS THE THE NYC AREA AND NORTH JERSEY. WITH
THE UPPER LEVEL JET STREAK SHIFTING EASTWARD...THE LIGHT SNOW LOOKS
TO TAPER OFF FOR A SHORT PERIOD DURING THE MORNING HOURS. MUCH OF
THE MORNING MAY BE RELATIVELY QUIET...WITH LIMITED ACCUMULATION.
HOWEVER...MORE SNOW WILL BUILD INTO THE AREA FOR THE AFTERNOON...AS
SFC LOW PRESSURE STARTS TO ORGANIZE ALONG THE BOUNDARY ACROSS THE
OHIO VALLEY ALONG WITH A WEAK SHORTWAVE AT 500 HPA. ISENTROPIC
LIFT/WARM AIR ADVECTION AHEAD OF THIS FEATURE WILL ALLOW STEADY SNOW
TO BREAK OUT DURING THE AFTN. DESPITE WARMING TEMPS ALOFT...IT
SHOULD REMAIN COLD ENOUGH OVER THE ENTIRE REGION FOR P-TYPE TO FALL
ENTIRELY AS SNOW...EVEN FOR FAR SOUTHERN AREAS...WHERE THERE WAS
INITIALLY SOME CONCERN FOR SOME MIXING TO OCCUR. A FEW INCHES OF
SNOWFALL /ABOUT ONE TO THREE INCHES/ LOOK TO OCCUR FOR THE AFTERNOON
THROUGH THE EARLY EVENING HOURS.
AS THE SFC LOW TRACKS ALONG THE SFC BOUNDARY SOUTH OF THE AREA
TONIGHT ACROSS PENNSYLVANIA...MORE STEADY SNOW WILL CONTINUE THROUGH
THE ENTIRE OVERNIGHT PERIOD. SOME PERIODS OF MODERATE SNOW ARE
POSSIBLE...ESPECIALLY FOR THE HIGH TERRAIN AREAS. THE OVERNIGHT
PERIOD LOOKS TO BE THE HEAVIEST ACCUMULATION OF SNOWFALL FOR THIS
EVENT SO FAR...WITH AN ADDITIONAL 3-6 INCHES EXPECTED
OVERNIGHT...WITH LOCALLY HIGHER AMOUNTS.
TEMPS DURING THE DAY TODAY LOOK TO WARM INTO THE 20S FOR MOST AREAS.
A FEW SPOTS IN THE MID HUDSON VALLEY MAY REACH 30-31...BUT SHOULD
STAY BELOW FREEZING. JUST TEENS ARE EXPECTED FOR THE ADIRONDACKS AND
SRN GREEN MOUNTAINS. TEMPS EVERYWHERE LOOK TO FALL TONIGHT THANKS TO
STREGHTENING NORTHERLY WINDS OF 5-10 KTS AT LOW LEVELS...WITH MIN
TEMPS IN THE SINGLE DIGITS AND TEENS.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
A WINTER STORM WARNING FOR THE ENTIRE FORECAST AREA CONTINUES
THROUGH 600 AM TUESDAY MORNING...
MODELS CONTINUE TO LARGELY BE IN AGREEMENT BOTH OVER THE PAST
RUNS...AND AMONG THEMSELVES WITH ONLY MODEST SPREAD IN THE
ENSEMBLES. THE EXCEPTION IS THE NAM...WHICH IS CONSIDERED AN
OUTLIER AND DISCARDED AS IT EXHIBITS KNOWN BIASES.
BY MORNING THE SFC LOW IS CENTER JUMPING THOUGH THE MTNS OF
WVA/VA AS A SHARPENING 500 HPA SHORT WV BEGINS ACCELERATING THE
PROCESS OF CYCLOGENISUS. DURING MON THE EVENT TRANSITIONS FROM A
LONG TERM OVERRUNNING DRIVEN STEADY LIGHT TO OCNL MODERATE
SNOW...INTO A FULL FLEDGED COASTAL LOW. AS SUCH UVM INCREASES AS
AREA COMES UNDER THE INFLUENCE OF THE WARM...THEN COLD
CONVEYER BELTS AS WELL AS UVM ASSOC WITH THE APPROACHING SHORT WV
AND DEEPENING COAST LOW. SNOWFALL RATES SHOULD INCREASE TWRD
DAYBREAK MON HWVR REMAIN GENERALLY 0.5 TO 1 INCH PER HOUR AT BEST.
OVERALL INTENSITY AND SNOWFALL RATES WILL REMAIN CAPPED AS THE
500HPA TROF REMAINS PROGRESSIVE AND THE SFC SYSTEM ONLY SLOWLY
DEEPENS...BEFORE THE WHOLE SYSTEM SLIDES OFFSHORE TWRD DAYBREAK
TUES.
AS THE CURRENT FORECAST STILL REMAINS IN GOOD SHAPE WILL ONLY
NUDGE GRIDS WITH BLENDING IN OF DATA FROM OVERNIGHT GFS/ECMWF.
WARNINGS LOOK GOOD WITH NO CHANGES. ALL WARNINGS LOOK GOOD WITH NO
CHANGES EXPECTED.
TUESDAY THIS COASTAL LOW AND ITS SHORT WV DEPART AND A HIGH
PRESSURE RIDGE BUILDS S FROM THE PARENT SFC HIGH OVER ONT/QB...BRINGING
A BRIEF PERIOD OF FAIR COLD WC TUE INTO TUE NT.
WED IN THE FAST ZONAL 500HPA FLOW OVER THE N TIER OF THE USA...A
SERIES OF SHORT WVS BEGIN ENTERING THE REGION...THEN QUICKLY CARVE
OUT A TROF OVER THE GRTLKS. THE NEXT CLIPPER SFC LOW TAKES SHAPE
IN THE UPR GRTLKS WED MRNG...AND DIVES SE...DEEPENING RAPIDLY AND
REACHING PA BY 12UTC THU. CLOUDS WILL INCR WED ACROSS THE FCA...WITH
-SN REACHING THE W AREAS BY LATE AFTN...AND SPREADING ACROSS THE
RGN OVERNIGHT. AN INCH OR SO IS POSSIBLE BY MORNING WITH MORE
AFTWRDS. TEMPS THROUGH THIS PERIOD WILL AVERAGE 5-10 DEG BLO
NORMAL.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
STRONG 500HPA TROF...AND CLIPPER LOW IMPACT REGION THU WITH
PERIODS OF LIGHT SNOW. TEMPS WILL BE NEAR NORMAL AT FIRST. BUT AS
THE SFC LOW BOMBS OFFSHORE...STRONG WINDS WILL DEVELOP...AND TEMPS
WILL PLUNGE DURING THE AFTN AND EVNG...AS ARCTIC AIR POURS INTO
REGION ON STRONG N WNDS. THU NT 18-22HPA SFC WIND GRADIENT ACROSS
NYS. WIND CHILL FLAGS MAY NEED TO BE CONSIDERED.
THE GFS KEEPS THE COASTAL LOW CLOSE ENOUGH TO ENHANCE SNOW
AMOUNTS/QPF CONSIDERABLY OVER ECMWF. GFS PLUMES HAVE 0.02-0.4 LIQ
EQ QPF WITH ONE OUTLIER OF 0.6. BUT THERE`S PLENTY OF TIME TO SEE
HOW THAT EVOLVES AND CHC -SN OR -SNSH THU AND THU NT WILL SUFFICE.
FRI AND FRI NT WILL BE FAIR AS ARCTIC HIGH CRESTS ACROSS QB AND
NE...BUT QUICKLY EXITS TO THE EAST FRI NT. WITH SFC WINDS MAINLY N
ANY LK ONTARIO LES WILL BE SHORT MULTIBANDS WELL TO OUR WEST.
SAT ANOTHER POWERFUL CLIPPER (ECMWF) IMPACTS THE FCA WITH MORE
-SHSN...THEN IS FOLLOWED BY EVEN COLDER AIR. THERE REMAINS SPREAD
IN THE MODEL SOLUTIONS AS THE GFS TAKES THIS CLIPPER AND ITS
PCPN TO OUT SOUTH...ONLY LEAVING US THE FRIGID AIR AND 1000-500
DM THICKNESSES DROPPING TO 480 OR S DM OVER THE FCA NEXT WEEKEND.
BRRR.
FOR THE EFP HPC ONLY HAS CHC POPS WITH THU EVENT AND LEANS TOTALLY
TWRD GFS SOLUTION BYND THAT. WILL BLEND HPC/GFS/ECMWF IN EFP
THINKING WITH CHC SN THU INTO FRI AM WITH FIRST CLIPPER. GEN FAIR
AND DRY CONDS FRI WITH INCR CLOUDS FRI NT. WILL LEAN TWRD A HYBRID
SOLUTION SAT WITH STRONG WINDS IN CAA AND CHC -SHSN WHETHER IS
WITH 2ND CLIPPER OR SHORT WVS OR TRRN ENHANCED THERE WILL BE SOME
-SHSN AROUND.
TEMPS DURING THIS PERIOD WILL BE WELL BELOW NORMAL...BECOMING
FRIGID/VERY WELL BLO NORMAL BY THE END OF EFP.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
LIGHT SNOW WILL CONTINUE THROUGH THE REMAINDER OF THE OVERNIGHT
HOURS. SNOW HAS YET TO BEGIN AT KPOU...BUT LOOKS TO BEGIN SHORTLY.
WITHIN SNOWFALL...IFR VSBY OF 1 TO 2 SM WILL BE IN PLACE...WITH
CIGS VARYING BETWEEN 900 FEET AND 4000 FEET...DEPENDING ON SNOW
INTENSITY. MOST SITES WILL SEE CIGS GENERALLY ON THE LOWER END OF
THE RANGE FOR 08Z-12Z.
THERE MAY BE A BRIEF BREAK IN THE SNOW FOR SUNDAY MORNING AFTER
SUNRISE. HAVE RAISED FLYING CONDITIONS TO MVFR FOR SEVERAL HOURS
IN THE MORNING AT ALL SITES SHOWING THE BREAK IN THE SNOWFALL.
HOWEVER...WITH ANOTHER WAVE MOVING ALONG THE NEARBY SFC
BOUNDARY...SNOWFALL WILL BUILD BACK INTO THE ENTIRE AREA FOR THE
AFTN AND EVENING HOURS...WITH IFR/LIFR VSBYS AND CIGS EXPECTED FOR
SUN AFTN THROUGH SUN NIGHT.
CALM WINDS OVERNIGHT WILL BECOME LIGHT FROM A N-NE DIRECTION FOR
ALL SITES. N-NE WINDS ARE EXPECTED TO BE AROUND 5-10 KTS ON SUNDAY
FOR ALL SITES.
OUTLOOK...
MONDAY THROUGH MONDAY NIGHT: HIGH OPERATIONAL IMPACT. PERIODS OF
SN.
TUESDAY THROUGH WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
WEDNESDAY THROUGH THURSDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF
SN.
&&
.HYDROLOGY...
NO SIGNIFICANT HYDROLOGIC PROBLEMS ARE EXPECTED THE NEXT 7 DAYS.
BELOW TO MUCH BELOW NORMAL TEMPERATURES WILL BE THE GENERAL RULE
WHICH WILL ALLOW ICE TO THICKEN ON RIVERS...STREAMS CREEKS...LAKES
AND OTHER BODIES OF WATER.
PERIODS OF LIGHT TO MODERATE SNOW WILL OCCUR THROUGH MONDAY NIGHT
WITH A FOOT OR MORE OF SNOW ACROSS MOST OF THE REGION. THERE WILL
BE ANOTHER BURST OF SNOW LATE IN THE WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WINTER STORM WARNING UNTIL 6 AM EST TUESDAY FOR CTZ001-013.
NY...WINTER STORM WARNING UNTIL 6 AM EST TUESDAY FOR NYZ032-033-
038>043-047>054-058>061-063>066-082>084.
MA...WINTER STORM WARNING UNTIL 6 AM EST TUESDAY FOR MAZ001-025.
VT...WINTER STORM WARNING UNTIL 6 AM EST TUESDAY FOR VTZ013>015.
&&
$$
SYNOPSIS...SNYDER
NEAR TERM...FRUGIS
SHORT TERM...SNYDER
LONG TERM...SNYDER
AVIATION...FRUGIS
HYDROLOGY...BGM/SNYDER/WASULA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1009 PM EST MON FEB 9 2015
.SYNOPSIS...
A BROAD AREA OF LOW PRESSURE WILL PASS OFF THE CAROLINA COAST
TONIGHT, WITH HIGH PRESSURE BUILDING OVER THE REGION FROM THE
NORTHWEST FOR TUESDAY AND WEDNESDAY. A COLD FRONT WILL CROSS THE
AREA THURSDAY, WITH A STRONG LOW PRESSURE SYSTEM EXPECTED TO DEVELOP
ALONG THIS FRONT AS IT MOVES OFF THE COAST. VERY COLD AIR AND STRONG
WINDS ARE EXPECTED FOR THE MID-ATLANTIC REGION BEHIND THIS FRONT
THURSDAY NIGHT AND FRIDAY. A CLIPPER SYSTEM MAY EFFECT THE AREA ON
SATURDAY, FOLLOWED BY YET ANOTHER BLAST OF COLD AIR ON SUNDAY AND
MONDAY AS ANOTHER CANADIAN HIGH PRESSURE SYSTEM MOVES EAST.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
A FEW CHANGES WITH THIS UPDATE. A MAJORITY OF THE HI-RES GUIDANCE
HAS NOT BEEN HANDLING THE CURRENT PRECIPITATION ACROSS SEPA TOO
WELL, ALTHOUGH THE HRRR IS THE BETTER OF THE GUIDANCE. USED A
HEAVY BLEND OF CONTINUITY AND HRRR THROUGH TUESDAY MORNING. THE
TRANSITION LINE FROM FZRA TO SNOW IS STILL SITTING ACROSS SEPA
INTO CENTRAL NEW JERSEY BASED ON REGIONAL OBSERVATIONS. THE
FREEZING LAYER WILL CONTINUE TO SAG SOUTH-SOUTHEAST THROUGH THE
OVERNIGHT HOURS AND EVENTUALLY EVERYONE WILL CHANGE OVER TO A
SNOW/SLEET MIX...ALL SNOW NORTH OF THE DELMARVA AFTER MIDNIGHT.
DID NOT TOUCH THE CURRENT ADVISORIES AS MORE PRECIPITATION HAS
BLOSSOMED TO THE WEST OF THE REGION AND THOUGH ACROSS THE POCONOS
AND NORTHERN NEW JERSEY IT SHOULD BE MOSTLY SNOW, WHENEVER WE LOSE
THE INTENSITY OF THE PRECIPITATION THE COLUMN DRIES ENOUGH TO
INCLUDE SOME VERY PATCHY FREEZING DRIZZLE.
ACROSS THE DELMARVA TEMPERATURES HAVE DROPPED TO OR BELOW FREEZING
AND THE THERMAL PROFILE IS SHOWING THE MELTING LAYER AT 850MB
STILL ACROSS THE PHILLY METRO AREA...FREEZING RAIN WILL INCREASE
IN COVERAGE LATE THIS EVENING INTO THE EARLY TUESDAY MORNING HOURS
BEFORE A SNOW/SLEET PHASE CHANGE OCCURS.
LOW TEMPS TONIGHT WILL DROP INTO THE TEENS ACROSS THE FAR
NORTH...AND DROP INTO THE MID/UPPER 20S ELSEWHERE. WINDS WILL BE
MOSTLY N OR NE AT 10 TO 15 MPH OVERNIGHT...HIGHER ALONG THE SHORE
AREAS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
HIGH PRESSURE WELL TO THE NORTH WILL BEGIN TO BUILD TOWARDS THE
AREA. LOW PRESSURE ASSOCIATED WITH THE SYSTEM FROM THE NEAR TERM
WILL BE WELL TO THE SOUTH...BUT WILL BE STRENGTHENING WHILE MOVING
OFFSHORE. THE ONLY PCPN WE HAVE FOR TUESDAY WILL BE FOR THE MORNING
ACROSS THE DELMARVA AND SE NJ WHERE SLGT CHC OR SMALL CHC POPS WILL
BE FOUND. BY MORNING...TEMPS WILL LIKELY BE COLD ENOUGH FOR MOSTLY
LIGHT SNOW. SKY COVER TUESDAY WILL BE MOSTLY CLOUDY FOR THE MOST
PART...BUT SOME IMPROVEMENTS NORTH ARE POSSIBLE LATER TUE. WINDS
WILL BE MODERATE WITH WINDS MOSTLY NORTHERLY 10 TO 15 MPH AND GUSTS
IN THE LOW 20S MPH RANGE. HIGH TEMPS WILL MOSTLY BE IN THE 30S
ACROSS THE REGION.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE MID-LEVEL FLOW PATTERN FROM TUESDAY NIGHT THROUGH MONDAY OF NEXT
WEEK IS FORECAST TO BE PUNCTUATED BY TWO EXTREME TROUGHS...ONE
THURSDAY INTO FRIDAY...THE OTHER LATE SATURDAY THROUGH SUNDAY. SOME
OF THE COLDEST AIR OF THE SEASON...IF NOT THE COLDEST...WILL
INVADE THE NORTHEAST SECTION OF THE COUNTRY IN THEIR WAKE, WITH A
FLOW DIRECTLY FROM THE POLAR REGIONS.
TUESDAY NIGHT SHOULD BE FAIRLY TRANQUIL, WITH LIGHTER WINDS, PERHAPS
SLIGHTLY STRONGER NEAR THE COAST. NO PRECIPITATION IS EXPECTED, WITH
NORMAL TO SLIGHTLY BELOW NORMAL TEMPERATURES AS SURFACE HIGH
PRESSURE BUILDS OVER THE AREA. WEDNESDAY WILL FEATURE MAINLY CLEAR SKIES
FOR A GOOD PART OF THE DAY, BUT SOME HIGH CLOUDS ARE POSSIBLE IN
THE WEST LATE. HIGH TEMPERATURES ON WEDNESDAY WILL BE SEVERAL
DEGREES BELOW NORMAL. LIGHT SNOW IS POSSIBLE IN THE NORTHERN HALF
OF THE CWA WEDNESDAY NIGHT AS A CLIPPER SYSTEM MOVES THROUGH NEW
YORK STATE. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM WILL MOVE
ACROSS THE AREA ON THURSDAY, USHERING IN BITTER COLD AIR FOR
THURSDAY NIGHT AND FRIDAY. THE ASSOCIATED MID-LEVEL TROUGH IS
EXPECTED TO BECOME NEGATIVELY TILTED JUST AS IT SWINGS THROUGH OUR
AREA THURSDAY NIGHT, SO RAPID DEVELOPMENT OF A SURFACE LOW IS
EXPECTED ONCE AGAIN OVER THE NEW ENGLAND MARITIMES.
UNFORTUNATELY...THE GRADIENT GENERATED BY THIS DEPARTING BUT
DEEPENING LOW PRESSURE SYSTEM WILL BRING GUSTY NORTHWEST WINDS TO
OUR AREA...DRIVING WIND CHILL TEMPERATURES DOWN TO THE NEGATIVE
TEENS (AND PERHAPS BEYOND IN THE HIGHER ELEVATIONS UP NORTH) FOR
THURSDAY NIGHT. HIGH TEMPERATURES ON FRIDAY WILL STRUGGLE TO
EMERGE OUT OF THE SINGLE DIGITS IN THE FAR NORTH, AND WON`T GET
OUT OF THE LOW TO MID 20S IN THE SOUTH...SOME TWENTY DEGREES BELOW
NORMAL FOR THIS TIME OF YEAR. ANOTHER COLD NIGHT IS ON TAP FOR
FRIDAY NIGHT, BUT WITH LESS WIND IT MIGHT NOT FEEL QUITE SO
COLD...AND THE HOUSE WILL BE A LITTLE EASIER TO HEAT.
THEN ANOTHER BLAST HEADS OUR WAY ON SATURDAY, HERALDED BY A CLIPPER
SYSTEM WITH SOME LIGHT SNOW FROM WEST TO EAST STARTING IN THE
AFTERNOON. THIS CLIPPER COULD INTENSIFY AS IT MOVES OFF THE COAST
SATURDAY NIGHT, BRINGING GUSTY WINDS BACK TO THE AREA JUST AS COLD
AIR ONCE AGAIN INVADES THE REGION BEHIND A COLD FRONT. TEMPERATURES
SATURDAY NIGHT AND SUNDAY COULD BE COLDER THAN THE MIDWEEK SYSTEM
AND PERHAPS EVEN COLDER SUNDAY NIGHT GOING INTO MONDAY, BUT BY LATE
SUNDAY WINDS SHOULD BE SUBSIDING JUST A BIT.
ALL-IN-ALL, NOT A VERY NICE WEEK AHEAD...UNLESS YOU/RE A POLAR BEAR!
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TONIGHT...MVFR/IFR. AREAS OF FREEZING RAIN/SNOW/SLEET ACROSS THE
REGION TONIGHT. AT THIS POINT RDG/ABE SHOULD SEE THE MOST SNOW,
THOUGH ONLY A LIGHT ACCUMULATION, WITH TIMES OF SLEET MIXING IN
THROUGH THE REMAINDER OF THE EVENING. THERE COULD BE A PERIOD LATE
TONIGHT WHERE SOME PATCHY FREEZING DRIZZLE OCCURS. ELSEWHERE
FREEZING RAIN WILL BE THE MAIN PRECIPITATION THROUGH THE EVENING
BEFORE CHANGING OVER TO A SNOW/SLEET MIX AFTER MIDNIGHT. NORTHEAST
WINDS AROUND 10 TO 15 KNOTS MAY BECOME GUSTY AT TIMES.
TUESDAY...MVFR TO POCKETS OF IFR CONDITIONS ARE EXPECTED EARLY
TUESDAY MORNING AS ANY REMAINING LIGHT SNOW WILL BE ENDING FROM WEST
TO EAST. LIGHT SNOW SHOULD TAPER OFF FIRST DURING THE EARLY MORNING
FOR THE WESTERN SITES, INCLUDING KRDG/KABE, AND THEN WITHIN A COUPLE
OF HOURS EITHER SIDE OF DAYBREAK ACROSS THE DELAWARE VALLEY AND THEN
ACROSS NJ. MVFR CONDITIONS WILL LIKELY HOLD THROUGH THE MORNING,
BEFORE TRANSITIONING TO VFR INTO THE AFTERNOON. NORTH-NORTHEAST TO
NORTHERLY WINDS ARE ANTICIPATED THROUGH THE DAYTIME, WITH GUSTS
AROUND 20 KNOTS EXPECTED.
OUTLOOK...
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...MAINLY VFR WITH SUBSIDING
WINDS.
THURSDAY...MAINLY VFR. HOWEVER, THERE IS A CHANCE OF LIGHT SNOW WHICH
COULD BRIEFLY REDUCE CONDITIONS INTO THE MVFR OR IFR CATEGORY.
THURSDAY NIGHT THROUGH FRIDAY NIGHT FRIDAY...MAINLY VFR.
SATURDAY...A CHANCE OF LIGHT SNOW COULD ONCE AGAIN REDUCE CONDITIONS
IN THE THE MVFR OR IFR CATEGORY.
&&
.MARINE...
HIGH PRESSURE WELL TO THE NORTH WILL MOVE TOWARDS THE AREA LATE
TONIGHT. MEANWHILE...LOW PRESSURE WILL MOVE OFFSHORE (VA/NC) THEN
DEEPEN WHILE MOVING NE. THE PRESSURE GRADIENT WILL BEGIN TO
STRENGTHEN ACROSS THE AREA WITH WINDS/SEAS BUILDING. SCA FLAGS
WILL REMAIN FOR DEL BAY. THE GALE FLAG FOR THE NRN WATERS
CONTINUES THRU 23Z TUE...WHILE THE DEL BAY AND SRN COASTAL WATERS
HAS THE FLAGS THRU 03Z WED. THESE ENDING TIMES ARE OK FOR NOW.
OUTLOOK...
TUESDAY NIGHT...A GALE WARNING IS IN EFFECT UNTIL 1000 PM ON OUR
OCEAN WATERS SOUTH OF GREAT EGG INLET, NEW JERSEY. OTHERWISE, SMALL
CRAFT ADVISORY CONDITIONS SHOULD CONTINUE IN OUR MARINE AREA.
WEDNESDAY...SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED ON OUR
OCEAN WATERS.
WEDNESDAY NIGHT AND THURSDAY MORNING...WAVE HEIGHTS ON OUR OCEAN
WATERS MAY REMAIN NEAR 5 FEET. WIND SPEEDS ARE FORECAST TO STAY
BELOW THE SMALL CRAFT ADVISORY CRITERION.
THURSDAY AFTERNOON...SMALL CRAFT ADVISORY CONDITIONS ARE
ANTICIPATED TO RETURN WITH A DEVELOPING NORTHWEST WIND.
THURSDAY NIGHT AND FRIDAY...NORTHWESTERLY GALE FORCE GUSTS ARE
EXPECTED.
FRIDAY NIGHT...SMALL CRAFT ADVISORY WINDS EXPECTED.
SATURDAY...NO HEADLINES EXPECTED ATTM.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR PAZ054-
055-061-062-105.
WINTER WEATHER ADVISORY UNTIL 6 AM EST TUESDAY FOR PAZ060-070-
071-101>104-106.
NJ...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NJZ001-
007>010.
WINTER WEATHER ADVISORY UNTIL 6 AM EST TUESDAY FOR NJZ012>027.
DE...WINTER WEATHER ADVISORY UNTIL 6 AM EST TUESDAY FOR DEZ001>004.
MD...WINTER WEATHER ADVISORY UNTIL 6 AM EST TUESDAY FOR MDZ008-012-
015-019-020.
MARINE...GALE WARNING UNTIL 10 PM EST TUESDAY FOR ANZ452>455.
GALE WARNING UNTIL 6 PM EST TUESDAY FOR ANZ450-451.
SMALL CRAFT ADVISORY UNTIL 10 PM EST TUESDAY FOR ANZ430-431.
&&
$$
SYNOPSIS...MIKETTA
NEAR TERM...HEAVENER/O`HARA
SHORT TERM...O`HARA
LONG TERM...MIKETTA
AVIATION...HEAVENER/KLINE/MIKETTA
MARINE...MIKETTA/O`HARA
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1021 PM EST MON FEB 9 2015
.SYNOPSIS...
A COLD FRONT WILL CONTINUE PUSHING EAST TONIGHT BRINGING SHOWERS
TO THE AREA. FAIR WEATHER EXPECTED TUESDAY AND WEDNESDAY WITH
GENERALLY SEASONAL TEMPERATURES. A DRY COLD FRONT WILL MOVE
THROUGH THURSDAY...FOLLOWED BY MUCH COLDER CONDITIONS FRIDAY
THROUGH THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AN UPPER TROUGH TO OUR WEST WILL CONTINUE TO PROMOTE A CHANCE OF
SHOWERS OVERNIGHT AS IT SWINGS EAST. THE COLD FRONT IS LOCATED
ALONG THE WESTERN PART OF THE FORECAST AREA AND WILL CONTINUE TO
CROSS THE REGION TONIGHT. MAIN BAND OF RAINFALL AHEAD OF THE
FRONT HAS SHIFTED OFF THE COAST. REGIONAL RADAR IMAGERY
SHOWS SCATTERED SHOWERS IN THE UPSTATE WHICH ARE NOW MOVING INTO
THE CSRA AND WESTERN MIDLANDS. HRRR MODEL KEEPS LIGHT RAIN IN
THE NORTHERN MIDLANDS INTO TUESDAY MORNING. TEMPERATURES DROPPED
AS THE RAIN MOVED THROUGH EARLIER AND HAVE REMAINED RATHER STEADY.
LOOKING UPSTREAM...THE COLD SURGE OF AIR HAS BEEN LAGGING...SO
EXPECT OVERNIGHT LOWS TO BE MILD...IN THE 40S. WINDS WILL INCREASE
OVERNIGHT AS THE PRESSURE GRADIENT TIGHTENS AND COLD AIR ADVECTION
INCREASES. WINDS WILL INCREASE TO AROUND 10 TO 15 KNOTS WITH GUSTS
AROUND 20 TO 25 KNOTS BY 12Z. AREAS OF FOG HAVE DEVELOPED BUT
EXPECT IMPROVEMENT WITH THE NEXT BATCH OF SHOWERS AND AS WINDS
PICK UP AFTER 06Z.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
TUESDAY WILL START OFF MOSTLY CLOUDY...THEN AS DRIER AIR FINALLY
BEGINS WORKING ITS WAY INTO THE REGION BEHIND THE COLD FRONT SKIES
WILL BEGIN CLEARING BY THE AFTERNOON. WINDS WILL BECOME GUSTY
THROUGH THE DAY BEHIND THE FRONT DUE TO A RATHER STRONG PRESSURE
GRADIENT ACROSS THE REGION. WINDS GENERALLY OUT OF THE NORTH
BETWEEN 10 AND 15 MPH...WITH GUSTS AROUND 20 MPH BEING POSSIBLE.
DO NOT EXPECT LAKE WIND ADVISORY CRITERIA TO BE MET AT THIS
TIME...SO DO NOT ANTICIPATE ANY PRODUCT ISSUANCES. WINDS WILL
DIMINISH BY SUNSET. TEMPERATURES MAY BE ABLE TO CLIMB INTO THE
MIDDLE TO POSSIBLY UPPER 50S DURING THE AFTERNOON DEPENDING ON HOW
MUCH SUN THE REGION GETS.
DRY WEATHER IS EXPECTED TO CONTINUE FOR THE REMAINDER OF THE SHORT
TERM. THERE WILL BE ANOTHER FRONTAL PASSAGE ON THURSDAY...WHICH
WILL BRING INCREASING WINDS BACK TO THE REGION. WEDNESDAY AND
THURSDAY WILL STILL BE GENERALLY IN THE 50S FOR HIGHS...AND
OVERNIGHT LOWS IN THE 30S FOR TUESDAY NIGHT...THEN MODERATING INTO
THE 40S FOR WEDNESDAY NIGHT. THE COLDEST NIGHT WILL BE THURSDAY
NIGHT BEHIND THE COLD FRONT...WITH READINGS BACK DOWN INTO THE 20S
BECOMING POSSIBLE.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
THE DRY AIR WILL CONTINUE ACROSS THE REGION THROUGH THE WEEKEND.
BELOW NORMAL TEMPERATURES WILL ALSO CONTINUE. BIGGEST QUESTION
MARK IN REGARDS TO TEMPERATURES APPEARS TO BE OVER THE WEEKEND.
LARGE STANDARD DEVIATIONS IN THE MODEL GUIDANCE FOR BOTH MAX/MIN
READINGS. THIS IS DUE TO A POSSIBLE ARCTIC INTRUSION OF AIR
SATURDAY NIGHT INTO MONDAY. THE GFS/ECMWF/CMC SHOW STRONG AREA OF
HIGH PRESSURE MOVING INTO THE REGION SUNDAY AND MONDAY...WITH A
STRONG LOW MOVING OFF THE NEW ENGLAND COAST. IN GENERAL HAVE GONE
SLIGHTLY BELOW THE MODEL AVERAGES FOR TEMPERATURES SATURDAY NIGHT
THROUGH MONDAY...BUT DID NOT GO WITH THE EXTREME VALUES. THERE IS
SOME BITTERLY COLD AIR CURRENTLY ACROSS NORTH-CENTRAL AND WESTERN
CANADA...AND EASTERN ALASKA. WOULD PREFER TO WAIT AND SEE HOW MUCH
OF THIS AIR GETS PUSHED SOUTHWARD...ALONG WITH WHAT DIRECTION IT
HEADS...WITH THE POSSIBLE SURGE NEXT WEEKEND BEFORE GOING ON THE
EXTREME SIDE OF ANY GUIDANCE.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
WIDESPREAD IFR/LIFR CONDITIONS DUE TO FOG AND LOW STRATUS IN THE
CAE/CUB/OGB TERMINALS THIS EVENING. MVFR IN THE AGS TERMINAL AREA.
RADAR INDICATING SCATTERED SHOWERS IN THE UPSTATE SOUTH CAROLINA
MOVING SOUTHEAST TOWARD THE REGION. THESE SHOWERS WILL MOVE INTO
THE AREA MAINLY BETWEEN 04Z-06Z AND EXPECT VISIBILITIES AND CEILINGS
TO IMPROVE DURING THIS PERIOD. MAINLY MVFR FORECAST AFTER
05Z...ALTHOUGH LOW STRATUS STILL POSSIBLE. VISIBILITY EXPECTED TO IMPROVE.
NORTH WINDS EXPECTED TO INCREASE AFTER 09Z WITH GUSTS TO NEAR 20
KNOTS. UPPER LEVEL TROUGH AXIS OVER THE AREA OVERNIGHT AND ALONG
COAST TUESDAY. MODELS INDICATE CONSIDERABLE LOW-LEVEL MOISTURE
ACROSS REGION THROUGH TUESDAY MORNING WITH DRIER AIR ADVECTING IN
DURING THE AFTERNOON. THEREFORE...LOW CEILINGS...MVFR LIKELY TO
CONTINUE THROUGH THE MORNING WITH IMPROVEMENT TO VFR AROUND 18Z
WITH BROKEN STRATO-CU DECK. GUSTY NORTH WINDS TO CONTINUE THROUGH
THE DAY GUSTS TO ABOVE 20 KNOTS POSSIBLE.
EXTENDED AVIATION OUTLOOK...GUSTY WINDS MAY BE POSSIBLE AGAIN ON
THURSDAY BEHIND EXITING COLD FRONTS. CEILINGS AND VISIBILITIES
EXPECTED TO REMAIN VFR THROUGH THE EXTENDED PERIOD DUE TO A DRY
AIR MASS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
535 PM EST SUN FEB 8 2015
.SYNOPSIS...
A COLD FRONT WILL COME THROUGH MONDAY...PROVIDING SHOWERS AND
POSSIBLY AN ISOLATED THUNDERSTORM. FAIR WEATHER EXPECTED TUESDAY
AND WEDNESDAY WITH GENERALLY SEASONAL TEMPERATURES. A DRY COLD
FRONT WILL MOVE THROUGH THURSDAY...FOLLOWED BY MUCH COOLER
CONDITIONS FRIDAY INTO SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
COLD FRONT WILL REMAIN WEST OF THE FORECAST AREA OVERNIGHT.
SOUTHWESTERLY WINDS WILL REMAIN GENERALLY AROUND 5 MPH THROUGH THE
NIGHT. THE OVERNIGHT HOURS WILL REMAIN DRY...WITH ONLY A VERY
SLIGHT CHANCE OF LIGHT PRECIP GETTING CLOSE TO THE WESTERN CWA
TOWARDS MORNING. THIS IS CONSISTENT WITH HRRR MODEL SIMULATED
REFLECTIVITY. ALTHOUGH MOISTURE WILL INCREASE OVERNIGHT...THE
SURFACE WINDS ALONG WITH A LOW-LEVEL JET SHOULD HELP TO INHIBIT
ANY WIDESPREAD FOG. CAN NOT RULE OUT SOME PATCHY FOG THOUGH IN
ISOLATED LOCATIONS. OVERNIGHT LOWS RATHER MODERATE...WITH READINGS
AROUND 50 DEGREES.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
MONDAY AND MONDAY NIGHT...LOW PRESSURE WILL BEGIN THE DAY OVER
NORTHEASTERN WV WITH A COLD FRONT EXTENDING THROUGH THE CENTRAL
GULF STATES. THROUGH THE DAY THE LOW CENTER WILL MOVE
SOUTHEASTWARD REACHING NORTHERN NC BY MID EVENING THEN OFFSHORE
MONDAY NIGHT. THIS WILL BRING THE COLD FRONT THROUGH THE FORECAST
AREA DURING THE AFTERNOON HOURS WITH COOLER AND DRIER AIR MOVING
IN MONDAY NIGHT. MODELS CONTINUE TO INCREASE THE CHANCE OF RAIN
AND WITH THE UPPER LEVEL TROUGH CONTINUING TO AMPLIFY AND
SOUTHWESTERLY FLOW THROUGH THE DAY MONDAY USHERING GULF MOISTURE
INTO THE AREA HAVE SLIGHTLY INCREASED POPS FOR MONDAY AFTERNOON
INTO MONDAY EVENING. INSTABILITY REMAINS WEAK WITH FROPA...HOWEVER
THERE IS ENOUGH INSTABILITY AND FRONTAL LIFT TO REMAIN WITH
ISOLATED THUNDER DURING THE AFTERNOON AND EVENING HOURS. HIGH
TEMPERATURES MONDAY WILL BE IN THE MIDDLE TO UPPER 60S WITH LOWS
MONDAY NIGHT IN THE LOWER TO MIDDLE 40S.
TUESDAY AND TUESDAY NIGHT...LOW PRESSURE WILL TRACK FURTHER AWAY
FROM THE REGION TUESDAY AS HIGH PRESSURE AND WEAK UPPER LEVEL
RIDGING BUILD ACROSS THE AREA. THIS WILL BRING SLIGHTLY COOLER AND
DRIER AIR BACK TO THE REGION ALONG WITH MOSTLY CLEAR SKIES. WITH A
MODERATE PRESSURE GRADIENT OVER THE REGION DURING THE DAY TUESDAY
WINDS WILL BE NORTHERLY AROUND 10 MPH WITH GUSTS AROUND 15
MPH...WHICH WILL DISSIPATE DURING THE EVENING AS THE GRADIENT
WEAKENS. TEMPERATURES WILL RANGE FROM THE MID 50S IN THE NORTHERN
MIDLANDS TO AROUND 60 IN THE CSRA WITH OVERNIGHT LOWS IN THE LOWER
TO MIDDLE 30S.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
MODELS REMAIN IN GOOD AGREEMENT THROUGH THE LONG TERM WITH A QUICK
SUCCESSION OF SYSTEMS CROSSING THE REGION. HIGH PRESSURE WILL
REMAIN IN CONTROL OF THE REGION WEDNESDAY AS LOW PRESSURE TRACKS
THROUGH THE GREAT LAKES AND PUSHES A COLD FRONT INTO THE OHIO
VALLEY WEDNESDAY EVENING. THE COLD FRONT WILL CROSS THE MIDLANDS
DURING THE LATE MORNING/EARLY AFTERNOON HOURS THURSDAY AND MOVE
OFFSHORE THURSDAY EVENING. BEHIND THE FRONT COLDER AND DRIER AIR
WILL QUICKLY OVERTAKE THE REGION ALONG WITH A TIGHT PRESSURE
GRADIENT. HAVE INCREASED WIND SPEEDS FOR THURSDAY AND THURSDAY
NIGHT...HOWEVER MODELS INDICATE WIND SPEEDS COULD APPROACH 20 MPH
WITH HIGHER GUSTS THURSDAY AFTERNOON AND EVENING AS THE COLD AIR
ADVECTION MOVES INTO THE AREA. THE COLDER AIR AND HIGH PRESSURE
WILL REMAIN IN CONTROL OF THE AREA FOR FRIDAY THROUGH SUNDAY WITH
AN UPPER LEVEL DISTURBANCE MOVING NORTH OF THE AREA SATURDAY AND
SUNDAY. THIS WILL BRING SOME CLOUDINESS BACK TO THE FORECAST WITH
NO RAIN EXPECTED. TEMPERATURES THROUGH THE LONG TERM WILL BE
SLIGHTLY ABOVE NORMAL WEDNESDAY AND THURSDAY WITH BELOW NORMAL FOR
FRIDAY THROUGH SUNDAY.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
CONTINUED HIGH CONFIDENCE IN VFR CONDITIONS DURING THE 24 HR
FORECAST PERIOD.
SURFACE HIGH PRESSURE CENTERED OFF THE COAST WILL RESULT IN
SOUTHWESTERLY WINDS THROUGH THE PERIOD. SKIES MOSTLY CLEAR THROUGH
THE DAY AND INTO THE EARLY PORTIONS OF THE OVERNIGHT HOURS...THEN
SOME MID-LEVEL CLOUDINESS SHOULD ENTER THE FORECAST AREA AHEAD OF
AN APPROACHING COLD FRONT LATER TONIGHT. CLOUDS WILL REMAIN IN THE
VFR CATEGORY THROUGH THE PERIOD THOUGH. WINDS THROUGH THE
AFTERNOON WILL BE SOUTHWESTERLY AND GUSTY...WITH GUSTS OVER 20
KNOTS COMMON. WINDS WILL DIMINISH SOME BY SUNSET...BUT WILL REMAIN
SUSTAINED AROUND 5 KNOTS. THERE IS SOME CONCERN AGAIN TONIGHT THAT
A LOW-LEVEL JET OF 30-35 KNOTS COULD SET UP...WHICH COULD LEAD TO
THE INCLUSION OF LLWS IN THE LATER TAF ISSUANCES IF IT DOES.
MODELS SHOW AN INCREASING CHANCE FOR RAINFALL THROUGH THE DAY
MONDAY...HOWEVER THE CHANCE FOR ANY TAF SITES IS SMALL BETWEEN
12Z-18Z. THE BEST CHANCE FOR ANY KIND OF MEASURABLE RAINFALL WILL
PROBABLY BE CLOSER TO THE END OF THE TAF PERIOD.
EXTENDED AVIATION OUTLOOK...A FRONT MAY PROVIDE A CHANCE OF
SHOWERS MONDAY NIGHT. OTHERWISE NO SIGNIFICANT IMPACTS TO AVIATION
ARE EXPECTED FOR THE REMAINDER OF THE TAF PERIOD.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
906 PM CST MON FEB 9 2015
.UPDATE...
905 PM CST
NO MAJOR CHANGES TO THE GOING FORECAST FOR TONIGHT...OTHER THAN TO
TWEAK TEMPERATURE TRENDS A BIT IN AREAS THAT HAVE EXPERIENCED
CLEARING. HOWEVER...I DID BUMP POPS UP A BIT TUESDAY EVENING.
WATER VAPOR IMAGERY EARLY THIS EVENING INDICATES A RATHER HEALTHY
LOOKING SHORT WAVE IMPULSE PUSHING ONSHORE OVER NORTHERN CALIFORNIA
EARLY THIS EVENING. THIS FEATURE IS EXPECTED TRACK EASTWARD TONIGHT
AND ON TUESDAY...THEN SHIFT OVER NORTHERN ILLINOIS BY TUESDAY
EVENING. MEANWHILE...ENERGY NOW MOVING OVER WASHINGTON STATE AND
NORTHERN OREGON...WILL DRIVE A SURFACE SYSTEM ACROSS THE UPPER
MIDWEST LATE TUESDAY AND TUESDAY EVENING. A CORRIDOR OF INCREASING
WARM AIR ADVECTION/ISENTROPIC UPGLIDE IS EXPECTED TO SET UP
ACROSS MUCH OF THE UPPER MIDWEST IN ADVANCE THE APPROACHING SYSTEM
BY TUESDAY AFTERNOON AND EVENING...LIKELY SUPPORTING A GOOD AREA
OF PRECIPITATION.
THE MAIN QUESTION LOCALLY IS WILL THIS PRECIPITATION SHIELD DEVELOP
FAR ENOUGH SOUTHWARD TO IMPACT NORTHERN ILLINOIS. THERE CERTAINLY
SHOULD BE A GOOD AMOUNT OF DRY AIR TO OVERCOME TO GET PRECIPITATION TO
REACH THE GROUND. HOWEVER...IT APPEARS THAT AT LEAST A SHORT PERIOD
OF GOOD DYNAMIC FORCING FOR ASCENT SHOULD SET UP OVER NORTHERN
ILLINOIS AS THE AFOREMENTIONED MID LEVEL IMPULSE OVER NORTHERN CA
APPROACHES THE AREA TUESDAY EVENING. IT ALSO APPEARS THAT A CORRIDOR
OF SOME VERY IMPRESSIVE 7+ DEGREE C/KM LAPSE RATES WILL SET UP OVER
THE REGION CONCURRENT WITH THE PERIOD OF BEST FORCING. THEREFORE...I
DO HAVE SOME CONCERNS THAT THIS COULD RESULT IN A BAND OF MODERATE
TO POSSIBLY EVEN BRIEFLY HEAVY SNOW MOVING EASTWARD OVER NORTHERN
ILLINOIS DURING THE EVENING. THE GOOD NEWS IS IT APPEARS THAT IF
THIS DOES INDEED SET UP...IT WOULD BE A FAIRLY QUICK HITTING
EVENT...BUT THE POSSIBLY DOES EXIST FOR SOME AREAS TO GET A QUICK
HALF INCH TO AN INCH OF SNOW OUT OF THIS...GIVEN THE GOOD POSSIBLY
FOR SOME HEAVIER PRECIP RATES.
AT THE PRESENT TIME...I HAVE REMAINED CONSERVATIVE...RAISING POPS
ONLY UP TO AROUND 40 PERCENT FAR NORTH. THE MID SHIFT MAY NEED TO BE
RAISE THESE FARTHER...AND INCLUDE SOME MINOR ACCUMULATIONS.
KJB
&&
.SHORT TERM...
308 PM CST
THROUGH TUESDAY...
THE PRIMARY SHORT TERM FORECAST CHALLENGES ARE WITH THE DEGREE OF
CLEARING AND ITS ASSOCIATED IMPACTS ON TEMPERATURES. LOW-LEVEL
CYCLONIC FLOW HAD KEPT STRATUS FOR MUCH OF AREA TODAY BUT CLEARING
HAS NOW WORKED ITS WAY INTO NORTH CENTRAL ILLINOIS AS OF
MID-AFTERNOON DUE TO IN PART SUBSIDENCE BEHIND A DEPARTING SHORT
WAVE. EXTRAPOLATING ITS PROGRESS HAS THE ENTIRE AREA CLEAR BY
MID-EVENING...BUT BELIEVE THE RATE OF CLEARING WILL CONSIDERABLY
SLOW AFTER DARK...AS WELL AS THE LAKE EFFECT CLOUD FETCH KEEPING
LAKE-ADJACENT AREAS MAINLY CLOUDY. OVERALL GUIDANCE HAS REALLY
STRUGGLED WITH THE CLOUD COVER TODAY AND WENT MORE WITH THE GUT ON
CLOUDS AND TEMPERATURE TRENDS FOR TONIGHT. CLOUDS MAY ACTUALLY
EXPAND BACK WESTWARD INTO NORTH CENTRAL ILLINOIS OVERNIGHT AS
CLOUD-BEARING FLOW TURNS MORE EASTERLY. DO NOT HAVE MUCH DROP IN
CHICAGO AND THE SOUTHERN FORECAST AREA...WHILE CLEARING FROM THE
EAST MAY SCOUR NORTHWEST INDIANA THIS EVE. EXPECT THE SHARPEST RATE
OF COOLING TO BE IN THE CLEAR NORTH CENTRAL IL WHERE SURFACE RIDGING
WILL ALSO PROTRUDE INTO...AS WELL AS WITH CONTINUED MODEST SNOW
DEPTHS OF 5 TO 9 INCHES PER COOP/COCORAHS OBSERVERS. EXPECT TO SEE
TEMPERATURES VARYING BY A HIGH AMOUNT ACROSS THE AREA BY MID-LATE
EVENING DEPENDING ON CLEAR OR CLOUDS OVERHEAD.
SOME LOW CLOUDS MAY LINGER ON TUESDAY MORNING IN THE ILLINOIS PART
OF THE FORECAST AREA TO BE REPLACED BY THICKENING CIRRUS IN THE
AFTERNOON. RETURNING SOUTHERLY FLOW SHOULD HELP TEMPERATURES REACH
THE UPPER 20S TO LOWER 30S...ESPECIALLY FOR THOSE AREAS THAT DO NOT
DROP MUCH TONIGHT.
MTF
&&
.LONG TERM...
308 PM CST
TUESDAY NIGHT THROUGH MONDAY...
THE ATTENTION IN THE LONG RANGE IS ON TWO SHARP COLD PUNCHES
INDICATED BY A GOOD MAJORITY OF LONG RANGE GUIDANCE...WHICH WOULD
BE SUPPORTED IN THE OVERALL LARGE SCALE PATTERN OF DEVELOPING
RIDGING IN THE WEST AND STRENGTHENING NORTHWEST FLOW ALOFT OVER
THE REGION. WITH EACH OF THESE PUNCHES COMES GUSTY WINDS AND
BLUSTERY DAYS THURSDAY AND SATURDAY...AS WELL AS LAKE EFFECT SNOW
THREAT...POSSIBLY SIGNIFICANT...IN SOME PART OF NORTHWEST INDIANA
AND/OR SOUTHEAST MICHIGAN.
THE FIRST SYSTEM IS PRECEDED BY A MINOR SHORT WAVE ON TUESDAY NIGHT
WHICH IS PRESENTLY OVER THE PACIFIC NORTHWEST. THIS WAVE BRINGS WITH
IT MID-LEVEL CONVERGENCE AND STEEPENING LAPSE RATES...THOUGH
SATURATION MAY STRUGGLE ESPECIALLY WITH IT CENTERED TO THE NORTH OF
THE FORECAST AREA. HAVE ADDED SOME TUESDAY EVENING CHANCES OF LIGHT
SNOW WITH THE MENTION OF A BRIEF START AS SLEET...AND CONTINUED
THE OVERNIGHT CHANCES IN THE FORECAST. NOT EXPECTING ANY REAL
ACCUMULATION WITH THIS.
AFTER A SOMEWHAT MILD DAY WEDNESDAY WITH INCREASING WESTERLY FLOW
AHEAD OF THE PRIMARY TROUGH...THE MAIN WAVE WILL DIG SOUTHEASTWARD
WEDNESDAY NIGHT BRINGING WITH IT A SUBSTANTIALLY COLDER AIR MASS.
CONFIDENCE IS MEDIUM-HIGH THAT MOST OF THE PRECIP WITH THIS FEATURE
WILL BE EAST OF THE AREA. GIVEN THE FORECAST PROJECTION OF THE COLD
FRONTAL PASSAGE WEDNESDAY NIGHT AND THE STRONG NORTHWEST
WINDS...GUSTING TO 30 TO 35 MPH...TEMPERATURES SHOULD REALLY
STRUGGLE TO CLIMB ON THURSDAY. WIND GUSTS MAY EVEN BE HIGHER AT
TIMES GIVEN THE REGIONAL PRESSURE GRADIENT. AM NOT EXPECTING MUCH
OF A BLOWING SNOW ISSUE AT PRESENT GIVEN THE RESIDUAL TIME OF THE
CURRENT SNOW PACK.
LAKE EFFECT SNOW PARAMETERS BECOME WELL-DEFINED BY THURSDAY WITH
850MB TEMPERATURES BELOW -20C ADVECTING OVER THE LAKE AND GOOD
SYNOPTIC PLACEMENT OF THE PRESSURE GRADIENT...WHICH COULD SUPPORT
WINDS CLOSE TO DUE NORTH FOR A PERIOD AND FAVOR AT LEAST PORTER
COUNTY TO GET INTO SOME LAKE EFFECT SNOW. OVER HALF OF THE
MATCHING CIPS ANALOGS TO THE 12Z GFS FORECAST SUPPORT OVER SIX
INCHES SOMEWHERE IN THE NORTHWEST INDIANA TO SOUTHWEST MICHIGAN
REGION...SO CERTAINLY SOMETHING TO WATCH.
AGAIN MODELS ARE IN STRONG AGREEMENT ON A REPEAT OF THIS SCENARIO
BUT EVEN TO A STRONGER MAGNITUDE FRIDAY NIGHT INTO SATURDAY.
ANOMALY SIGNALS IN THE SYNOPTIC WIND COMPONENT AND TEMPERATURES
IN THE GFS ENSEMBLE ARE HIGH FOR A COLD AIR SURGE. WHILE THE AIR
MASS MAY MODIFY WITH TIME...AGAIN THE LONG RANGE PATTERN ALL THE
WAY NORTHWARD TO SOME CROSS-POLAR FLOW WOULD FAVOR POSSIBLY HIGHS
IN THE SINGLE DIGITS SATURDAY. GIVEN ITS FURTHER DISTANCE OUT IN
THE FORECAST AND BEHIND THE AFOREMENTIONED SYSTEM...WILL HAVE TO
WATCH THIS DIGGING SYSTEM EVEN MORE...AS IT COULD END UP WORKING
FURTHER WEST THAN ITS CURRENT PROJECTION. IF THIS WERE TO PAN OUT
IT WOULD FAVOR POTENTIAL FOR SYNOPTIC SNOW SHOWERS CORRELATING
WITH THOSE GUSTY WINDS. FOR RIGHT NOW HAVE FOCUSED ON THE LAKE
EFFECT SNOW POTENTIAL IN NORTHWEST INDIANA AND TRENDED WELL ABOVE
MODEL GUIDANCE FOR SNOW CHANCES SATURDAY AND SATURDAY NIGHT.
DESPITE THE MESOSCALE NATURE OF THIS...THE SYNOPTIC SIGNAL FOR
SOMEWHERE IN THE REGION TO GET GOOD LAKE EFFECT IS STRONG FOR THIS
FAR OUT...AS EVIDENCED BY ANOMALIES AND ANALOGS.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* LAKE EFFECT MVFR CIGS AT MDW PROBABLY SPREADING BACK INTO ORD
* SOME LAKE EFFECT FLURRIES/LIGHT SNOW SHOWERS THIS EVENING
* SMALL CHANCE OF LIGHT SNOW OR GRAUPEL TUES EVENING
IZZI
//DISCUSSION...UPDATED 00Z...
LAKE EFFECT CLOUDINESS WITH MVFR CIGS WILL CONTINUE THROUGH MUCH
OF TONIGHT AT MDW AND GYY WITH CIGS PROBABLY SLOSHING BACK
NORTHWEST INTO ORD LATER TONIGHT AS FLOW TURNS MORE EASTERLY.
WARMING TEMPERATURES SHOULD CAUSE LAKE CLOUDINESS TO BREAK UP LATE
TONIGHT OR EARLY TUESDAY MORNING SO EXPECTING LOW CIGS TO CLEAR
DESPITE CONTINUED FLOW OFF THE LAKE WHICH WILL TURN MORE
SOUTHEASTERLY TUES AFTERNOON AND EVENING. WARM FRONT WILL MOVE
ACROSS THE REGION TUESDAY NIGHT AND WHILE I AM EXPECTING MAINLY A
VIRGA EVENT THERE COULD BE A FEW SNOW OR GRAUPEL (ICE PELLET)
SHOWERS TO PENETRATE THROUGH THE DRY LOW LEVELS TUES EVENING.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* LOW/MEDIUM CONFIDENCE IN MVFR CIG TRENDS TONIGHT/TUES MORNING
* FAIRLY HIGH CONFIDENCE IN REMAINDER OF FORECAST
IZZI
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
WEDNESDAY...MVFR CIGS LIKELY. GUSTY NW WINDS IN AFTERNOON.
THURSDAY...MVFR CIGS. CHANCE OF FLURRIES. GUSTY NW WINDS.
FRIDAY...CHANCE OF MVFR CIGS. SW WINDS.
SATURDAY...MVFR CIGS/FLURRIES. STRONG/GUSTY NW WINDS.
SUNDAY...CHANCE OF MVFR CIGS...MAINLY EARLY.
IZZI
&&
.MARINE...
216 PM CST
GALES WEDNESDAY NIGHT AND THURSDAY WITH ANOTHER ROUND
POSSIBLE SATURDAY WILL BE THE MAIN FOCUS OF THE FORECAST. LOW
PRESSURE OVER THE MID-ATLANTIC STATES THIS AFTERNOON WILL MOVE INTO
THE WESTERN ATLANTIC TONIGHT THEN STRENGTHEN AS IT CONTINUES OUT TO
SEA. HIGH PRESSURE CENTERED OVER NORTHERN MANITOBA HAS A RIDGE AXIS
EXTENDING INTO THE MID AND UPPER MISSISSIPPI RIVER VALLEY AND WILL
STEADILY MOVE EAST ACROSS LAKE MICHIGAN TONIGHT AND TUESDAY MORNING.
WINDS WILL STEADILY DIMINISH THIS EVENING AND TONIGHT WHILE TURNING
FROM NORTH OR NORTHEAST TO SOUTHEAST BY LATE MORNING. LOW PRESSURE
WILL MOVE FROM CENTRAL MONTANA TO MINNESOTA BY TUESDAY NIGHT WHILE
WEAKENING BUT AN UPPER LEVEL TROUGH WILL CATCH UP TO IT HELPING IT
TO STRENGTHEN AS IT MOVES ACROSS THE U.P. OF MICHIGAN...NORTHERN
LAKE HURON AND TO LAKE ONTARIO WEDNESDAY AND WEDNESDAY NIGHT. VERY
STRONG CANADIAN HIGH PRESSURE WILL MOVE INTO THE NORTHERN PLAINS
BEHIND THE LOW THURSDAY. THE COMBINATION OF THE DEEPENING LOW AND
THE VERY STRONG HIGH...IN CONJUNCTION WITH AN INTRUSION OF VERY COLD
AIR WILL PROVIDE AN IDEAL GALE SET UP ACROSS LAKE MICHIGAN WEDNESDAY
NIGHT THROUGH MOST OF THURSDAY. TIMING OF THE ARRIVAL OF GALES STILL
NEEDS TO BE REFINED BUT THINGS COULD QUICKLY RAMP UP AS EARLY AS 00Z
WEDNESDAY EVENING. AT THIS POINT 40 TO PERHAPS 45 KT GUSTS ARE
FAVORED. WILL HOLD OFF ON A GALE WATCH AT THE MOMENT GIVEN THAT
THE START TIME IS BEYOND 48 HOURS AND THE NEEDED REFINEMENT TO THE
TIMING. WIND DIRECTION WILL SHIFT FROM NORTHWEST TO NORTH-
NORTHWEST AS SPEEDS RAMP UP ALLOWING FOR A LONG FETCH FOR WAVE
DEVELOPMENT.
THE HIGH STEADILY WEAKENS AS IT MOVE ACROSS THE WESTERN LAKES AND
MISSISSIPPI RIVER VALLEY THURSDAY NIGHT AND FRIDAY. ANOTHER LOW WILL
DROP SOUTHEAST FROM NORTHERN MANITOBA WITH ANOTHER STRONG HIGH
TRAILING IT WHICH WILL LIKELY SUPPORT ANOTHER ROUND OF NORTH TO
NORTHWEST GALES FRIDAY NIGHT OR SATURDAY.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 3 AM TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
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[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
855 PM CST Mon Feb 9 2015
.UPDATE...
ISSUED AT 855 PM CST MON FEB 9 2015
Main forecast concern for the rest of the night revolves around
how much clearing to expect. A ridge of high pressure extending
from northwest Ontario, through the upper Midwest, and along the
west side of the middle and lower Mississippi River Valley, will
slowly push east overnight. Substantial clearing as developed
over Wisconsin and lower Michigan, with a finger of clearing along
the ridge axis into northwest Missouri. The details of the
clearing are not very well handled by any explicit model solution,
so confidence in the evolution of the clearing is low. A more
substantial low level inversion is evident in the 00Z KILX
sounding than is suggested by local model soundings. While this
may suggest the low clouds hanging tough for a longer period of
time, a similar inversion existed in the 00Z KDVN sounding, and
skies have cleared there. So, updated forecast to go a little more
optimistic with clearing for the rest of the night, especially
considering the low-level flow beneath the inversion is coming
from the currently clear areas of WI/MI. Have also had to nudge
low temperatures down a bit in the areas that have or are most
likely to clear overnight.
&&
.SHORT TERM...(Tonight)
ISSUED AT 253 PM CST MON FEB 9 2015
Low clouds blanket much of IL this afternoon with some clearing
working southward from WI into far nw IL nearing Rockford. HRRR
model shows some of this clearing working southward into areas nw of
the IL river late this evening and overnight with low clouds
breaking up around Wabash river valley by 09Z/3 am. 12Z DVN/ILX
soundings show a strong inversion trapping low level moisture/clouds
so will go slower with the clearing of low clouds keeping most areas
cloudy into this evening and them becoming partly to mostly cloudy
overnight. 1033 mb Canadian high pressure over Manitoba and ridging
south into the Midwest will drift east across Ontario tonight and
Tue morning with ridge axis into IL by 18Z/noon Tue. This should
further help decrease low clouds especially by Tue morning. Brisk
north winds 8-18 mph and gusts 18-25 mph at mid afternoon to veer ne
toward overnight and diminish under 10 mph as high pressure ridge
moves in. Temps have been nearly steady today in mid to upper 20s
over central IL and lower 30s in southeast IL south of I-70 and from
Jacksonville sw. Lows tonight of 15-19F over 1-3 inch snow pack
north of Lincoln where low clouds decrease sooner, and lower 20s
south of Lincoln.
&&
.LONG TERM...(Tuesday through Monday)
ISSUED AT 253 PM CST MON FEB 9 2015
Briefly warmer conditions through Wednesday will be followed with an
extended period of below normal temps as an upper ridge builds in
the western CONUS and a trough deepens into the eastern CONUS.
Measurable precip will be minimal in our area during that time, but a
couple periods of flurries or light snow showers may develop in the
wake of the cold fronts Wed night and Saturday as upper level
shortwaves dive southeast in the cold northwest flow.
The 12z models have continued the farther north track of the surface
pressure and precip shield with the mid-week storm system. The main
change in our forecast looks to be just behind the cold front
Wednesday night when a shortwave rotates from Minnesota farther
south into Illinois. Despite limited moisture when the wave arrives,
flurries or light snow showers could develop northeast of a line
from Springfield to Effingham. Little to no accumulation is expected
at this time, but any increase in available moisture could allow
for light snow accums.
The first surge of Arctic air for Wed night into Thursday has
trended colder with the 12z GFS/NAM/Canadian, now showing 850mb
temps down toward -22C to -23C into our counties. The ECMWF
remained around -19C to -20C. Still, our sensible weather will not
change appreciably in either case, with very cold wind chills
early Thursday morning down in the -5F to -15F range, amid
scattered flurries.
Friday will warm about 10-12F above Thurs, then the next even colder
Arctic surge will arrive on Saturday. 850mb temps are projected down
to -25C to -26C at 18z/Noon as a few flurries possibly develop under
a 500mb shortwave. Saturday night appears to be the coldest night of
the next week, with low temps in the single digits below zero N of
Peoria, and wind chills in the -15 to -18F range into Sunday
morning.
Temps begin to warm again on Sunday as another clipper moves across
the Great Lakes and light snow affects NE IL.
The far extended forecast shows a flattening of the west CONUS ridge
and eastern CONUS trough Monday. Low pressure advancing across the
central Plains could pass across central and southern IL Monday
night, with a swath of snow in our north and rain/snow south. Many
changes are likely with the track and timing of that system, but
it could be our next period of more significant precipitation.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
ISSUED AT 525 PM CST MON FEB 9 2015
Main issue with the TAFs tonight will be CIGs. Viewing
satellite...there appeared to be some clearing into Knox county.
However...uncertain to how far this clearing will extend over the
next few hours. Decided to keep prevailing MVFR CIGs for all
sites for the first six hours...except BMI where IFR CIGs will
remain for a large portion of the TAF period until tomorrow
morning. Guidance and the HRRR model show spotty clearing
throughout the night with CIGs bouncing around...so TAFs will be
amended as necessary to account for changes in flight category.
Otherwise...high pressure settling in over the state will bring
light winds out of the northeast turning to the southeast by
midday tomorrow for the TAF sites. If skies are to clear somewhat
overnight...light haze could develop with MVFR VIS possible in the
early to mid morning hours.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Bak
SHORT TERM...07
LONG TERM...Shimon
AVIATION...ALW
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
602 PM CST MON FEB 9 2015
.SHORT TERM...
308 PM CST
THROUGH TUESDAY...
THE PRIMARY SHORT TERM FORECAST CHALLENGES ARE WITH THE DEGREE OF
CLEARING AND ITS ASSOCIATED IMPACTS ON TEMPERATURES. LOW-LEVEL
CYCLONIC FLOW HAD KEPT STRATUS FOR MUCH OF AREA TODAY BUT CLEARING
HAS NOW WORKED ITS WAY INTO NORTH CENTRAL ILLINOIS AS OF
MID-AFTERNOON DUE TO IN PART SUBSIDENCE BEHIND A DEPARTING SHORT
WAVE. EXTRAPOLATING ITS PROGRESS HAS THE ENTIRE AREA CLEAR BY
MID-EVENING...BUT BELIEVE THE RATE OF CLEARING WILL CONSIDERABLY
SLOW AFTER DARK...AS WELL AS THE LAKE EFFECT CLOUD FETCH KEEPING
LAKE-ADJACENT AREAS MAINLY CLOUDY. OVERALL GUIDANCE HAS REALLY
STRUGGLED WITH THE CLOUD COVER TODAY AND WENT MORE WITH THE GUT ON
CLOUDS AND TEMPERATURE TRENDS FOR TONIGHT. CLOUDS MAY ACTUALLY
EXPAND BACK WESTWARD INTO NORTH CENTRAL ILLINOIS OVERNIGHT AS
CLOUD-BEARING FLOW TURNS MORE EASTERLY. DO NOT HAVE MUCH DROP IN
CHICAGO AND THE SOUTHERN FORECAST AREA...WHILE CLEARING FROM THE
EAST MAY SCOUR NORTHWEST INDIANA THIS EVE. EXPECT THE SHARPEST RATE
OF COOLING TO BE IN THE CLEAR NORTH CENTRAL IL WHERE SURFACE RIDGING
WILL ALSO PROTRUDE INTO...AS WELL AS WITH CONTINUED MODEST SNOW
DEPTHS OF 5 TO 9 INCHES PER COOP/COCORAHS OBSERVERS. EXPECT TO SEE
TEMPERATURES VARYING BY A HIGH AMOUNT ACROSS THE AREA BY MID-LATE
EVENING DEPENDING ON CLEAR OR CLOUDS OVERHEAD.
SOME LOW CLOUDS MAY LINGER ON TUESDAY MORNING IN THE ILLINOIS PART
OF THE FORECAST AREA TO BE REPLACED BY THICKENING CIRRUS IN THE
AFTERNOON. RETURNING SOUTHERLY FLOW SHOULD HELP TEMPERATURES REACH
THE UPPER 20S TO LOWER 30S...ESPECIALLY FOR THOSE AREAS THAT DO NOT
DROP MUCH TONIGHT.
MTF
&&
.LONG TERM...
308 PM CST
TUESDAY NIGHT THROUGH MONDAY...
THE ATTENTION IN THE LONG RANGE IS ON TWO SHARP COLD PUNCHES
INDICATED BY A GOOD MAJORITY OF LONG RANGE GUIDANCE...WHICH WOULD
BE SUPPORTED IN THE OVERALL LARGE SCALE PATTERN OF DEVELOPING
RIDGING IN THE WEST AND STRENGTHENING NORTHWEST FLOW ALOFT OVER
THE REGION. WITH EACH OF THESE PUNCHES COMES GUSTY WINDS AND
BLUSTERY DAYS THURSDAY AND SATURDAY...AS WELL AS LAKE EFFECT SNOW
THREAT...POSSIBLY SIGNIFICANT...IN SOME PART OF NORTHWEST INDIANA
AND/OR SOUTHEAST MICHIGAN.
THE FIRST SYSTEM IS PRECEDED BY A MINOR SHORT WAVE ON TUESDAY NIGHT
WHICH IS PRESENTLY OVER THE PACIFIC NORTHWEST. THIS WAVE BRINGS WITH
IT MID-LEVEL CONVERGENCE AND STEEPENING LAPSE RATES...THOUGH
SATURATION MAY STRUGGLE ESPECIALLY WITH IT CENTERED TO THE NORTH OF
THE FORECAST AREA. HAVE ADDED SOME TUESDAY EVENING CHANCES OF LIGHT
SNOW WITH THE MENTION OF A BRIEF START AS SLEET...AND CONTINUED
THE OVERNIGHT CHANCES IN THE FORECAST. NOT EXPECTING ANY REAL
ACCUMULATION WITH THIS.
AFTER A SOMEWHAT MILD DAY WEDNESDAY WITH INCREASING WESTERLY FLOW
AHEAD OF THE PRIMARY TROUGH...THE MAIN WAVE WILL DIG SOUTHEASTWARD
WEDNESDAY NIGHT BRINGING WITH IT A SUBSTANTIALLY COLDER AIR MASS.
CONFIDENCE IS MEDIUM-HIGH THAT MOST OF THE PRECIP WITH THIS FEATURE
WILL BE EAST OF THE AREA. GIVEN THE FORECAST PROJECTION OF THE COLD
FRONTAL PASSAGE WEDNESDAY NIGHT AND THE STRONG NORTHWEST
WINDS...GUSTING TO 30 TO 35 MPH...TEMPERATURES SHOULD REALLY
STRUGGLE TO CLIMB ON THURSDAY. WIND GUSTS MAY EVEN BE HIGHER AT
TIMES GIVEN THE REGIONAL PRESSURE GRADIENT. AM NOT EXPECTING MUCH
OF A BLOWING SNOW ISSUE AT PRESENT GIVEN THE RESIDUAL TIME OF THE
CURRENT SNOW PACK.
LAKE EFFECT SNOW PARAMETERS BECOME WELL-DEFINED BY THURSDAY WITH
850MB TEMPERATURES BELOW -20C ADVECTING OVER THE LAKE AND GOOD
SYNOPTIC PLACEMENT OF THE PRESSURE GRADIENT...WHICH COULD SUPPORT
WINDS CLOSE TO DUE NORTH FOR A PERIOD AND FAVOR AT LEAST PORTER
COUNTY TO GET INTO SOME LAKE EFFECT SNOW. OVER HALF OF THE
MATCHING CIPS ANALOGS TO THE 12Z GFS FORECAST SUPPORT OVER SIX
INCHES SOMEWHERE IN THE NORTHWEST INDIANA TO SOUTHWEST MICHIGAN
REGION...SO CERTAINLY SOMETHING TO WATCH.
AGAIN MODELS ARE IN STRONG AGREEMENT ON A REPEAT OF THIS SCENARIO
BUT EVEN TO A STRONGER MAGNITUDE FRIDAY NIGHT INTO SATURDAY.
ANOMALY SIGNALS IN THE SYNOPTIC WIND COMPONENT AND TEMPERATURES
IN THE GFS ENSEMBLE ARE HIGH FOR A COLD AIR SURGE. WHILE THE AIR
MASS MAY MODIFY WITH TIME...AGAIN THE LONG RANGE PATTERN ALL THE
WAY NORTHWARD TO SOME CROSS-POLAR FLOW WOULD FAVOR POSSIBLY HIGHS
IN THE SINGLE DIGITS SATURDAY. GIVEN ITS FURTHER DISTANCE OUT IN
THE FORECAST AND BEHIND THE AFOREMENTIONED SYSTEM...WILL HAVE TO
WATCH THIS DIGGING SYSTEM EVEN MORE...AS IT COULD END UP WORKING
FURTHER WEST THAN ITS CURRENT PROJECTION. IF THIS WERE TO PAN OUT
IT WOULD FAVOR POTENTIAL FOR SYNOPTIC SNOW SHOWERS CORRELATING
WITH THOSE GUSTY WINDS. FOR RIGHT NOW HAVE FOCUSED ON THE LAKE
EFFECT SNOW POTENTIAL IN NORTHWEST INDIANA AND TRENDED WELL ABOVE
MODEL GUIDANCE FOR SNOW CHANCES SATURDAY AND SATURDAY NIGHT.
DESPITE THE MESOSCALE NATURE OF THIS...THE SYNOPTIC SIGNAL FOR
SOMEWHERE IN THE REGION TO GET GOOD LAKE EFFECT IS STRONG FOR THIS
FAR OUT...AS EVIDENCED BY ANOMALIES AND ANALOGS.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* LAKE EFFECT MVFR CIGS AT MDW PROBABLY SPREADING BACK INTO ORD
* SOME LAKE EFFECT FLURRIES/LIGHT SNOW SHOWERS THIS EVENING
* SMALL CHANCE OF LIGHT SNOW OR GRAUPEL TUES EVENING
IZZI
//DISCUSSION...UPDATED 00Z...
LAKE EFFECT CLOUDINESS WITH MVFR CIGS WILL CONTINUE THROUGH MUCH
OF TONIGHT AT MDW AND GYY WITH CIGS PROBABLY SLOSHING BACK
NORTHWEST INTO ORD LATER TONIGHT AS FLOW TURNS MORE EASTERLY.
WARMING TEMPERATURES SHOULD CAUSE LAKE CLOUDINESS TO BREAK UP LATE
TONIGHT OR EARLY TUESDAY MORNING SO EXPECTING LOW CIGS TO CLEAR
DESPITE CONTINUED FLOW OFF THE LAKE WHICH WILL TURN MORE
SOUTHEASTERLY TUES AFTERNOON AND EVENING. WARM FRONT WILL MOVE
ACROSS THE REGION TUESDAY NIGHT AND WHILE I AM EXPECTING MAINLY A
VIRGA EVENT THERE COULD BE A FEW SNOW OR GRAUPEL (ICE PELLET)
SHOWERS TO PENETRATE THROUGH THE DRY LOW LEVELS TUES EVENING.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* LOW/MEDIUM CONFIDENCE IN MVFR CIG TRENDS TONIGHT/TUES MORNING
* FAIRLY HIGH CONFIDENCE IN REMAINDER OF FORECAST
IZZI
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
WEDNESDAY...MVFR CIGS LIKELY. GUSTY NW WINDS IN AFTERNOON.
THURSDAY...MVFR CIGS. CHANCE OF FLURRIES. GUSTY NW WINDS.
FRIDAY...CHANCE OF MVFR CIGS. SW WINDS.
SATURDAY...MVFR CIGS/FLURRIES. STRONG/GUSTY NW WINDS.
SUNDAY...CHANCE OF MVFR CIGS...MAINLY EARLY.
IZZI
&&
.MARINE...
216 PM CST
GALES WEDNESDAY NIGHT AND THURSDAY WITH ANOTHER ROUND
POSSIBLE SATURDAY WILL BE THE MAIN FOCUS OF THE FORECAST. LOW
PRESSURE OVER THE MID-ATLANTIC STATES THIS AFTERNOON WILL MOVE INTO
THE WESTERN ATLANTIC TONIGHT THEN STRENGTHEN AS IT CONTINUES OUT TO
SEA. HIGH PRESSURE CENTERED OVER NORTHERN MANITOBA HAS A RIDGE AXIS
EXTENDING INTO THE MID AND UPPER MISSISSIPPI RIVER VALLEY AND WILL
STEADILY MOVE EAST ACROSS LAKE MICHIGAN TONIGHT AND TUESDAY MORNING.
WINDS WILL STEADILY DIMINISH THIS EVENING AND TONIGHT WHILE TURNING
FROM NORTH OR NORTHEAST TO SOUTHEAST BY LATE MORNING. LOW PRESSURE
WILL MOVE FROM CENTRAL MONTANA TO MINNESOTA BY TUESDAY NIGHT WHILE
WEAKENING BUT AN UPPER LEVEL TROUGH WILL CATCH UP TO IT HELPING IT
TO STRENGTHEN AS IT MOVES ACROSS THE U.P. OF MICHIGAN...NORTHERN
LAKE HURON AND TO LAKE ONTARIO WEDNESDAY AND WEDNESDAY NIGHT. VERY
STRONG CANADIAN HIGH PRESSURE WILL MOVE INTO THE NORTHERN PLAINS
BEHIND THE LOW THURSDAY. THE COMBINATION OF THE DEEPENING LOW AND
THE VERY STRONG HIGH...IN CONJUNCTION WITH AN INTRUSION OF VERY COLD
AIR WILL PROVIDE AN IDEAL GALE SET UP ACROSS LAKE MICHIGAN WEDNESDAY
NIGHT THROUGH MOST OF THURSDAY. TIMING OF THE ARRIVAL OF GALES STILL
NEEDS TO BE REFINED BUT THINGS COULD QUICKLY RAMP UP AS EARLY AS 00Z
WEDNESDAY EVENING. AT THIS POINT 40 TO PERHAPS 45 KT GUSTS ARE
FAVORED. WILL HOLD OFF ON A GALE WATCH AT THE MOMENT GIVEN THAT
THE START TIME IS BEYOND 48 HOURS AND THE NEEDED REFINEMENT TO THE
TIMING. WIND DIRECTION WILL SHIFT FROM NORTHWEST TO NORTH-
NORTHWEST AS SPEEDS RAMP UP ALLOWING FOR A LONG FETCH FOR WAVE
DEVELOPMENT.
THE HIGH STEADILY WEAKENS AS IT MOVE ACROSS THE WESTERN LAKES AND
MISSISSIPPI RIVER VALLEY THURSDAY NIGHT AND FRIDAY. ANOTHER LOW WILL
DROP SOUTHEAST FROM NORTHERN MANITOBA WITH ANOTHER STRONG HIGH
TRAILING IT WHICH WILL LIKELY SUPPORT ANOTHER ROUND OF NORTH TO
NORTHWEST GALES FRIDAY NIGHT OR SATURDAY.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 3 AM TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
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WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
539 PM CST Mon Feb 9 2015
.SHORT TERM...(Tonight)
ISSUED AT 253 PM CST MON FEB 9 2015
Low clouds blanket much of IL this afternoon with some clearing
working southward from WI into far nw IL nearing Rockford. HRRR
model shows some of this clearing working southward into areas nw of
the IL river late this evening and overnight with low clouds
breaking up around Wabash river valley by 09Z/3 am. 12Z DVN/ILX
soundings show a strong inversion trapping low level moisture/clouds
so will go slower with the clearing of low clouds keeping most areas
cloudy into this evening and them becoming partly to mostly cloudy
overnight. 1033 mb Canadian high pressure over Manitoba and ridging
south into the Midwest will drift east across Ontario tonight and
Tue morning with ridge axis into IL by 18Z/noon Tue. This should
further help decrease low clouds especially by Tue morning. Brisk
north winds 8-18 mph and gusts 18-25 mph at mid afternoon to veer ne
toward overnight and diminish under 10 mph as high pressure ridge
moves in. Temps have been nearly steady today in mid to upper 20s
over central IL and lower 30s in southeast IL south of I-70 and from
Jacksonville sw. Lows tonight of 15-19F over 1-3 inch snow pack
north of Lincoln where low clouds decrease sooner, and lower 20s
south of Lincoln.
&&
.LONG TERM...(Tuesday through Monday)
ISSUED AT 253 PM CST MON FEB 9 2015
Briefly warmer conditions through Wednesday will be followed with an
extended period of below normal temps as an upper ridge builds in
the western CONUS and a trough deepens into the eastern CONUS.
Measurable precip will be minimal in our area during that time, but a
couple periods of flurries or light snow showers may develop in the
wake of the cold fronts Wed night and Saturday as upper level
shortwaves dive southeast in the cold northwest flow.
The 12z models have continued the farther north track of the surface
pressure and precip shield with the mid-week storm system. The main
change in our forecast looks to be just behind the cold front
Wednesday night when a shortwave rotates from Minnesota farther
south into Illinois. Despite limited moisture when the wave arrives,
flurries or light snow showers could develop northeast of a line
from Springfield to Effingham. Little to no accumulation is expected
at this time, but any increase in available moisture could allow
for light snow accums.
The first surge of Arctic air for Wed night into Thursday has
trended colder with the 12z GFS/NAM/Canadian, now showing 850mb
temps down toward -22C to -23C into our counties. The ECMWF
remained around -19C to -20C. Still, our sensible weather will not
change appreciably in either case, with very cold wind chills
early Thursday morning down in the -5F to -15F range, amid
scattered flurries.
Friday will warm about 10-12F above Thurs, then the next even colder
Arctic surge will arrive on Saturday. 850mb temps are projected down
to -25C to -26C at 18z/Noon as a few flurries possibly develop under
a 500mb shortwave. Saturday night appears to be the coldest night of
the next week, with low temps in the single digits below zero N of
Peoria, and wind chills in the -15 to -18F range into Sunday
morning.
Temps begin to warm again on Sunday as another clipper moves across
the Great Lakes and light snow affects NE IL.
The far extended forecast shows a flattening of the west CONUS ridge
and eastern CONUS trough Monday. Low pressure advancing across the
central Plains could pass across central and southern IL Monday
night, with a swath of snow in our north and rain/snow south. Many
changes are likely with the track and timing of that system, but
it could be our next period of more significant precipitation.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
ISSUED AT 525 PM CST MON FEB 9 2015
Main issue with the TAFs tonight will be CIGs. Viewing
satellite...there appeared to be some clearing into Knox county.
However...uncertain to how far this clearing will extend over the
next few hours. Decided to keep prevailing MVFR CIGs for all
sites for the first six hours...except BMI where IFR CIGs will
remain for a large portion of the TAF period until tomorrow
morning. Guidance and the HRRR model show spotty clearing
throughout the night with CIGs bouncing around...so TAFs will be
amended as necessary to account for changes in flight category.
Otherwise...high pressure settling in over the state will bring
light winds out of the northeast turning to the southeast by
midday tomorrow for the TAF sites. If skies are to clear somewhat
overnight...light haze could develop with MVFR VIS possible in the
early to mid morning hours.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...07
LONG TERM...Shimon
AVIATION...ALW
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
244 AM CST SUN FEB 8 2015
.UPDATE...
IT APPEARS THE THREAT OF LOW CLOUD DEVELOPMENT FOR MUCH OF THE
NIGHT WILL BE LOW. THE 00 UTC SOUNDING OUT OF KDVN IS VERY DRY
ABOVE 900 MB. MUCH OF THE LOWER CLOUD COVER CONTINUES TO BE
CONFINED NORTH OF THE SURFACE BOUNDARY OVER WISCONSIN.
THEREFORE...LOWER CLOUD COVER (OUTSIDE OF FOG DEVELOPMENT) DOES
NOT APPEAR LIKELY UNTIL SUNDAY MORNING AS THE COLDER AIR MASS TO
OUR NORTH BEGINS TO SAG BACK SOUTHWARD OVER NORTHERN ILLINOIS
FOLLOWING THE PASSAGE FOR THE SURFACE LOW. WITH ALL THIS IN
MIND...IT APPEARS THAT FOG DEVELOPMENT MAY END UP BEING THE
PRIMARY CONCERN OVERNIGHT...ESPECIALLY ACROSS NORTH CENTRAL
ILLINOIS WHERE TEMPERATURES HAVE COOLED INTO THE LOWER 30S. WITH
THE SURFACE LOW EXPECTED TO SHIFT RIGHT OVER NORTHERN ILLINOIS
LATE TONIGHT...LIGHT WINDS AND ABUNDANT NEAR SURFACE MOISTURE
SHOULD LEAD TO FOG...WITH THE POTENTIAL FOR SOME DENSE FOG.
I HAVE REMOVED THE MENTION OF DRIZZLE/FREEZING DRIZZLE OVERNIGHT
AS IT APPEARS TO BE LESS OF THREAT GIVEN THE LACK OF LOW LEVEL
CLOUDINESS.
KJB
&&
.SHORT TERM...
212 PM CST
THROUGH MONDAY...
CONCERNS AROUND FOG POTENTIAL TONIGHT...LOCALLY DENSE...MIXED
PRECIPITATION TURNING TO SNOW LATER SUNDAY INTO SUNDAY NIGHT.
WARM FRONT WHICH WAS BISECTING PORTIONS OF THE AREA TODAY IS NOW
LIFTING NORTHWARD. TEMPERATURES AREA WIDE HAVE REACHED THE UPPER 30S
TO LOW 40S AREA WIDE. WE HAVE A FEW STRAGGLER COLD SPOTS LIKE
ROCHELLE AND DEKALB THAT HAVE TRAILED BEHIND DUE TO SOME LINGERING
FOG. HIGH CLOUDS SHOULD LIMIT THE WARMING TREND THROUGH THE
AFTERNOON.
MODELS ARE STILL INSISTENT ON BREAKING OUT LOW CLOUDS AND ADDITIONAL
FOG LATE THIS AFTERNOON AND TONIGHT. DEWPOINTS NOW IN THE 30S...SO
CHANCES ARE INCREASING. RAP MODEL WHICH HAS HAD THE
MOST SUCCESS IN THIS REGIME ALONG WITH MOS GUIDANCE SUGGEST THAT IT
WILL STILL TAKE SOME TIME FOR CLOUDS AND FOG TO BECOME MORE
SOLIDIFIED. WILL STILL SEE SOME PATCHY FOG OR HAZE THIS EVENING...BUT
BETTER CHANCES COME OVERNIGHT...AS BETTER PERFORMING MOS GUIDANCE
SUGGESTS. WITH THE SURFACE LOW MOVING OVERHEAD...WINDS WILL
SLACKEN AND THUS AREAS FROM I-80 NORTHWARD STAND A BETTER CHANCE
FOR FOG DEVELOPMENT TONIGHT...LOCALLY DENSE. THERE IS A WEAK WAVE
IN THE WESTERLY FLOW ALOFT...AND IF WE ARE SATURATED
DOWNSTAIRS...THERE IS SOME WEAK TO MAYBE MODERATE LIFT IN THE LOW
LAYERS...INITIALLY ISENTROPIC UPGLIDE...THEN SOME VERY LOW
FRONTOGENETICAL FORCING THE AS THE 925 MB BOUNDARY BEGINS TO SINK
SOUTHEASTWARD. THAT COULD LEAD TO A LITTLE DRIZZLE OUT OF THE
STRATUS OVERNIGHT. GIVEN THE LACK OF STRATUS THUS FAR...NOT
EXPECTING A WHOLE LOT OF COVERAGE. DEWPOINTS ARE FORECAST TO BE
ABOVE FREEZING EXCEPT FOR MAYBE ALONG FAR NORTHERN ILLINOIS. WITH
THE NAM/RAP/SREF TRACKING THE SURFACE LOW THROUGH NORTHERN
ILLINOIS INSTEAD OF THROUGH CENTRAL ILLINOIS...BELIEVE THE MOST
AREAS SHOULD BE ABOVE FREEZING OVERNIGHT IF ANY PRECIPITATION IS
OCCURRING...EVEN THOUGH TEMPS IN NORTH CENTRAL ILLINOIS MAY DIP TO
FREEZING OR SO LATE TONIGHT.
ON SUNDAY THE SOUTHERN SHORTWAVE IS PROGGED TO MOVE THROUGH THE
AREA...MAINLY DURING THE LATER MORNING AND AFTERNOON. THE ASSOCIATED
SURFACE LOW WILL BE PASSING TO THE EAST WHICH WILL ALLOW SOME COOLER
LOW LEVEL AIR TO FILTER IN FROM THE NORTHWEST. CONCERNS ON THE
COVERAGE OF PRECIPITATION GIVEN THE A SIGNIFICANT DRY LAYER FROM
850-700 MB...WHICH SHOULD CERTAINLY MAKE FOR A GENERALLY DRY MORNING
PRECIPITATION WISE OTHER THAN SOME DRIZZLE OR SOME LIGHT RAIN SOUTH
AND EAST OF THE LOW THERMAL COLD FRONTAL BOUNDARY. THIS WOULD FAVOR
I-55 AND SOUTHEASTWARD. FORECAST SOUNDINGS SUGGEST A PRETTY
SIGNIFICANT LOW LEVEL WARM NOSE WILL BE ERODING
THROUGH THE AFTERNOON DURING THE HIGHEST LIKELIHOOD PERIOD FOR
PRECIPITATION...BUT EVEN THIS PERIOD OF TIME HI-RES MODELS ARE NOT
EXCITED ABOUT WIDESPREAD PRECIPITATION...DESPITE GLOBAL MODELS
PAINTING A FEW HUNDREDTHS OF PRECIPITATION AREA-WIDE. HAVE GENERALLY
CARRIED HIGH CHANCE POPS FOR THE AFTERNOON PERIOD WHEN WE WOULD HAVE
A BETTER CHANCE FOR DEEPER SATURATION. MOST AREAS EXCEPT IN THE
NORTHWEST SHOULD REMAIN ABOVE FREEZING FOR ALL RAIN DURING THE DAY.
A LITTLE COLDER AIR FILTERS INTO THE AREA SUNDAY NIGHT AS THE UPPER
TROUGH MOVES EAST AND THE SURFACE LOW HEADS TOWARD THE ATLANTIC
SEABOARD. NORTH/NORTHEAST FLOW SETS UP DOWN THE LAKE FOR A DECENT
PERIOD OF TIME...WHICH IS CERTAINLY FAVORABLE FOR LAKE EFFECT SNOW
SHOWERS. THE AIR MASS THIS TIME IS NOT QUITE AS COLD IN THE LOW
LEVEL CLOUD LAYER...SUGGESTING THAT SNOW PRODUCTION WOULD BE LESS
THAN IDEAL. BUT INVERSION HEIGHTS AND LAPSE RATES DO GET BETTER LATE
SUNDAY NIGHT AND INTO MONDAY. STILL...EVEN GLOBAL MODELS SPIT OUT
SOME QPF OVER NORTHEAST ILLINOIS OVERNIGHT INTO MONDAY MORNING...AND
A CONVERGENCE SIGNAL HANGING ON INTO NORTHWEST INDIANA THROUGH
MONDAY AFTERNOON. IN REALITY...THIS SIGNAL HANGS ON EVEN OVERNIGHT
FOR NW INDIANA WHERE LIGHT LAKE EFFECT SNOWS MAY
STILL CONTINUE. 850-700 RH IS DISSIPATING ALL THE WHILE ELSEWHERE...CLOUDS
MAY BE A LITTLE SLOWER TO CLEAR AS WE REMAIN IN CYCLONIC FLOW ALOFT
AND HIGH PRESSURE STILL LINGERS TO THE WEST. BUT MOST AREAS AWAY
FROM THE LAKE DRY OUT FAIRLY QUICKLY...ESPECIALLY OVERNIGHT INTO
MONDAY MORNING.
KMD
&&
.LONG TERM...
212 PM CST
MONDAY NIGHT THROUGH SATURDAY...
SURFACE HIGH PRESSURE BUILDS IN WITH A BIT MORE GUSTO ON MONDAY
NIGHT INTO TUESDAY...THOUGH HIGH CLOUDS WILL BE INCREASING THROUGH
THE DAY SOME MODEL DISAGREEMENT AS TO HOW MUCH THIS WAVE WILL
INTERACT WITH A MORE SIGNIFICANT UPPER TROUGH OF PACIFIC ORIGIN BUT
MUCH FARTHER NORTH...AND WILL PUSH SOUTHEAST THROUGH THE CANADIAN
PRAIRIES TOWARD OUR REGION LATER WEDNESDAY. IT LOOKS LIKE A PERIOD
OF LIGHT PRECIPITATION TUESDAY NIGHT INTO WEDNESDAY...WITH THE BEST
CHANCES I-88 NORTHWARD. PROFILES AT THIS POINT SUGGEST SNOW/SLEET
TRANSITIONING TO ALL SNOW. IF THE PRECIP GETS SOUTH OF I-80...IT
WOULD TRANSITION TO A RAIN/SNOW MIX ON WEDS.
ANOTHER GOOD SLUG OF COLD AIR WILL BE HEADING OUR WAY WITH THIS COLD
PUSH...ALONG WITH SOME DECENT WINDS. THE SURFACE WAVE IS NOT VERY
DEEP ASSOCIATED WITH THE TROUGH AND THE BETTER PRESSURE FALLS LOOK
TO REMAIN TO THE NORTH...BUT IT IS A PRETTY STRONG HIGH PROGGED TO
MOVE EASTWARD. WHILE EARLY THURSDAY WILL BE COLD AND WINDY...THE
HIGH MOVES OVERHEAD LATE THURSDAY AND THURSDAY NIGHT. WHILE WARM
ADVECTING....CLEAR SKIES AND LIGHT WINDS WILL MAKE FOR ANOTHER COLD
NIGHT THURSDAY NIGHT AND MORNING EARLY FRIDAY.
THE NEXT CHANCE FOR SNOW WOULD BE NEXT WEEKEND AS POTENTIAL
CROSS-POLAR FLOW ALOFT SETS UP AND MAY BRING ANOTHER COLD FRONT
THROUGH.
KMD
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* IFR STRATUS MAY DEVELOP AFT 11Z...AND COULD LINGER INTO MIDDAY.
* PATCHY FOG WILL CONTINUE...REDUCING VSBYS TO MVFR AND POSSIBLY FURTHER
TOWARDS IFR VSBYS JUST BEFORE DAYBREAK AND LINGER THRU MID-
MORNING.
* WINDS LIGHT FROM THE SOUTH/SOUTHWEST AND MAY BECOME CALM EARLY
THIS MORNING. WINDS THEN QUICKLY TURN NORTHWEST THEN JUST EAST
OF NORTH AT 010 DEG AFTER 21Z.
* RAIN OR SNOW SHOWERS ARE POSSIBLE AFT 21Z BUT LIMITED COVERAGE
AND LIGHT INTENSITY.
BEACHLER
//DISCUSSION...UPDATED 06Z...
IR IMAGERY CONTINUES TO SHOW A CIRRUS DECK SLIDING ACROSS THE
REGION...WITH SURFACE OBS NOT INDICATING ANY STARTUS AT THIS TIME.
SOME REDUCED VSBYS ARE BEGINNING TO DEVELOP ACROSS NORTHERN IL
AIRFIELDS...WITH MANY SITES WEST OF ORD/MDW ALREADY REDUCED TO
2-3SM. EXPECT AS TEMPERATURES SLOWLY FALL...ADDTL SITES WILL SEE
VSBYS REDUCED. AIRFIELDS WEST OF ORD/MDW WILL LIKELY SEE FOG BRING
VSBYS DOWN TO AROUND 1SM BY 10-11Z...AND ORD/MDW WILL BE DOWN TO
2-3SM. MEANWHILE GUIDANCE CONTINUES TO SUGGEST SOME STRATUS CLOUDS
WILL DEVELOP...AND SPREAD IN COVERAGE OVERNIGHT. ONCE THE
FOG/STRATUS DEVELOP...CONDITIONS SHOULD REMAIN REDUCED THROUGH
MID-MORNING. AS A LOW PRESSURE SYSTEM SLIDES OVERHEAD...WINDS WILL
BRIEFLY BECOME CALM FROM THE CURRENT LGT SOUTH/SOUTHWEST SETUP.
THEN WINDS WILL TURN NORTHWEST BUT REMAIN LGT OR LESS THAN 8KT. A
FRONTAL BOUNDARY WILL DRIVE SOUTH ACROSS THE AREA THIS
AFTERNOON...BRINGING WINDS QUICKLY TO THE NORTH AND SLIGHTLY
NORTHEAST ALONG WITH SPEEDS INCREASING TO ARND 10KT AND GUSTS
NEARING 16-18KT. WITH BETTER MIXING ARRIVING LATER THIS AFTN/EARLY
EVE...THE STRATUS DECK AND REDUCED VSBYS SHUD BEGIN TO IMPROVE
SLIGHTLY.
SOME PATCHY DRIZZLE MAY ALSO DEVELOP PRIOR TO THE ARRIVAL OF THE
LOW PRESSURE SYSTEM...WITH A FEW LIGHT RAIN SHOWERS LATER THIS
AFTERNOON. BUT GIVEN THE CONFIDENCE IN THIS PLAYING OUT HAVE OPTED
TO HOLD OFF ON MENTION OF DRIZZLE AS THEIR REMAINS AN ABUNDANCE OF
DRY AIR ALOFT...AND COVERAGE FOR SHOWERS LOOKS TO REMAIN MINIMAL
AND WILL CARRY VCSH AT THIS TIME.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* LOW-MEDIUM IN IFR CIGS DEVELOPING. LOW IN REACHING LIFR. LOW IN
START TIME AND DURATION.
* LOW IN IFR VISIBILITY SUNDAY MORNING AND DURATION OF FOG.
* MEDIUM-HIGH IN WINDS TURNING NORTH-NORTHEAST ON SUNDAY AFTERNOON
AND PERSISTING INTO SUNDAY NIGHT.
* LOW-MEDIUM ON PRECIPITATION CHANCES BUT HIGH THAT IF ANY OCCURS
PRIOR TO 21Z SUNDAY IT WILL BE LIGHT AND LIQUID.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...MVFR AND A CHANCE FOR LIGHT SNOW IN THE MORNING. NORTH
WINDS.
TUESDAY...MVFR DURING THE NIGHT WITH POSSIBLE IFR. CHANCE OF SNOW
OR SLEET. SOUTHEAST WINDS.
WEDNESDAY...MVFR WITH IFR POSSIBLE. CHANCE OF SNOW. NORTHWEST
WINDS.
THURSDAY...VFR. NORTHWEST WINDS.
FRIDAY...MVFR POSSIBLE. CHANCE OF SNOW DURING THE NIGHT. SOUTHWEST
WINDS.
MTF
&&
.MARINE...
202 AM CST
A FRONTAL BOUNDARY REMAINS ACROSS THE NORTHERN SECTIONS OF THE LAKE
EARLY THIS MORNING...AND WILL SAG SOUTH THROUGH THE DAY. AS A LOW
PRESSURE SYSTEM APPROACHES LAKE MICHIGAN THIS AFTERNOON...THE FRONT
WILL BEGIN TO SLIDE SOUTH FASTER AND REACH THE SOUTHERN TIP OF LAKE
MICHIGAN LATE THIS AFTERNOON. WINDS TO THE NORTH OF THE BOUNDARY
HAVE INCREASED AS A RESULT OF THE TIGHTER GRADIENT...GUSTING TO 25KT
AT TIMES. FURTHER SOUTH THE SOUTHERLY WINDS HAVE PERSISTED BETWEEN
10-20KT. AS THE TIGHTER GRADIENT SLIDES SOUTH THIS AFTERNOON...WINDS
WILL QUICKLY TURN NORTH/NORTHEAST AND INCREASE TO 20-25KT. THIS WILL
LIKELY CREATE HAZARDOUS WINDS TO SMALL CRAFT BY MID-AFTERNOON FOR
THE NORTHERN IL NEARSHORE WATERS. VISIBLE SATELLITE IMAGERY FROM SUN
INDICATES CONSIDERABLE ICE COVERAGE REMAINS. AT THIS TIME HAVE OPTED
TO KEEP MENTION OF WAVES OUT OF THE NEARSHORE PRODUCT BUT MAY NEED
TO ADD WAVES BACK IN DEPENDING ON HOW EXTENSIVE THE ICE IS LATER
TODAY.
WITH COLDER AIR SLIDING SOUTH BEHIND THE FRONTAL BOUNDARY...WINDS
MAY AT TIMES GUST TO 30KT THIS EVENING. BUT EXPECT THE BULK OF THE
WINDS TO BE BETWEEN 20-25KT. HIGH PRESSURE BUILDS IN FROM THE WEST
MONDAY AND WILL BRING A STEADY DECREASE IN THE GRADIENT AND LIGHTER
WINDS. HIGH PRESSURE QUICKLY SLIDES EAST TUESDAY WITH YET ANOTHER
LOW PRESSURE SYSTEM ARRIVING. WINDS WILL TURN SOUTHERLY AHEAD OF THE
NEXT LOW PRESSURE...BEFORE TURNING WEST TO NORTH BEHIND A COLD FRONT
WEDNESDAY. THE NEXT CHANCE FOR GALES APPEARS TO BE BEHIND THE FRONT
WEDNESDAY NIGHT INTO THURSDAY AS VERY STRONG HIGH PRESSURE BUILDS
FRONT THE CANADIAN PRAIRIES INTO THE UPPER MIDWEST.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741...2 PM SUNDAY TO 10 AM
MONDAY.
SMALL CRAFT ADVISORY...LMZ742-LMZ743-LMZ744-LMZ745...6 PM SUNDAY
TO 10 AM MONDAY.
&&
$$
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
NWS CHICAGO/ROMEOVILLE IL
203 AM CST SUN FEB 8 2015
.UPDATE...
IT APPEARS THE THREAT OF LOW CLOUD DEVELOPMENT FOR MUCH OF THE
NIGHT WILL BE LOW. THE 00 UTC SOUNDING OUT OF KDVN IS VERY DRY
ABOVE 900 MB. MUCH OF THE LOWER CLOUD COVER CONTINUES TO BE
CONFINED NORTH OF THE SURFACE BOUNDARY OVER WISCONSIN.
THEREFORE...LOWER CLOUD COVER (OUTSIDE OF FOG DEVELOPMENT) DOES
NOT APPEAR LIKELY UNTIL SUNDAY MORNING AS THE COLDER AIR MASS TO
OUR NORTH BEGINS TO SAG BACK SOUTHWARD OVER NORTHERN ILLINOIS
FOLLOWING THE PASSAGE FOR THE SURFACE LOW. WITH ALL THIS IN
MIND...IT APPEARS THAT FOG DEVELOPMENT MAY END UP BEING THE
PRIMARY CONCERN OVERNIGHT...ESPECIALLY ACROSS NORTH CENTRAL
ILLINOIS WHERE TEMPERATURES HAVE COOLED INTO THE LOWER 30S. WITH
THE SURFACE LOW EXPECTED TO SHIFT RIGHT OVER NORTHERN ILLINOIS
LATE TONIGHT...LIGHT WINDS AND ABUNDANT NEAR SURFACE MOISTURE
SHOULD LEAD TO FOG...WITH THE POTENTIAL FOR SOME DENSE FOG.
I HAVE REMOVED THE MENTION OF DRIZZLE/FREEZING DRIZZLE OVERNIGHT
AS IT APPEARS TO BE LESS OF THREAT GIVEN THE LACK OF LOW LEVEL
CLOUDINESS.
KJB
&&
.SHORT TERM...
212 PM CST
THROUGH MONDAY...
CONCERNS AROUND FOG POTENTIAL TONIGHT...LOCALLY DENSE...MIXED
PRECIPITATION TURNING TO SNOW LATER SUNDAY INTO SUNDAY NIGHT.
WARM FRONT WHICH WAS BISECTING PORTIONS OF THE AREA TODAY IS NOW
LIFTING NORTHWARD. TEMPERATURES AREA WIDE HAVE REACHED THE UPPER 30S
TO LOW 40S AREA WIDE. WE HAVE A FEW STRAGGLER COLD SPOTS LIKE
ROCHELLE AND DEKALB THAT HAVE TRAILED BEHIND DUE TO SOME LINGERING
FOG. HIGH CLOUDS SHOULD LIMIT THE WARMING TREND THROUGH THE
AFTERNOON.
MODELS ARE STILL INSISTENT ON BREAKING OUT LOW CLOUDS AND ADDITIONAL
FOG LATE THIS AFTERNOON AND TONIGHT. DEWPOINTS NOW IN THE 30S...SO
CHANCES ARE INCREASING. RAP MODEL WHICH HAS HAD THE
MOST SUCCESS IN THIS REGIME ALONG WITH MOS GUIDANCE SUGGEST THAT IT
WILL STILL TAKE SOME TIME FOR CLOUDS AND FOG TO BECOME MORE
SOLIDIFIED. WILL STILL SEE SOME PATCHY FOG OR HAZE THIS EVENING...BUT
BETTER CHANCES COME OVERNIGHT...AS BETTER PERFORMING MOS GUIDANCE
SUGGESTS. WITH THE SURFACE LOW MOVING OVERHEAD...WINDS WILL
SLACKEN AND THUS AREAS FROM I-80 NORTHWARD STAND A BETTER CHANCE
FOR FOG DEVELOPMENT TONIGHT...LOCALLY DENSE. THERE IS A WEAK WAVE
IN THE WESTERLY FLOW ALOFT...AND IF WE ARE SATURATED
DOWNSTAIRS...THERE IS SOME WEAK TO MAYBE MODERATE LIFT IN THE LOW
LAYERS...INITIALLY ISENTROPIC UPGLIDE...THEN SOME VERY LOW
FRONTOGENETICAL FORCING THE AS THE 925 MB BOUNDARY BEGINS TO SINK
SOUTHEASTWARD. THAT COULD LEAD TO A LITTLE DRIZZLE OUT OF THE
STRATUS OVERNIGHT. GIVEN THE LACK OF STRATUS THUS FAR...NOT
EXPECTING A WHOLE LOT OF COVERAGE. DEWPOINTS ARE FORECAST TO BE
ABOVE FREEZING EXCEPT FOR MAYBE ALONG FAR NORTHERN ILLINOIS. WITH
THE NAM/RAP/SREF TRACKING THE SURFACE LOW THROUGH NORTHERN
ILLINOIS INSTEAD OF THROUGH CENTRAL ILLINOIS...BELIEVE THE MOST
AREAS SHOULD BE ABOVE FREEZING OVERNIGHT IF ANY PRECIPITATION IS
OCCURRING...EVEN THOUGH TEMPS IN NORTH CENTRAL ILLINOIS MAY DIP TO
FREEZING OR SO LATE TONIGHT.
ON SUNDAY THE SOUTHERN SHORTWAVE IS PROGGED TO MOVE THROUGH THE
AREA...MAINLY DURING THE LATER MORNING AND AFTERNOON. THE ASSOCIATED
SURFACE LOW WILL BE PASSING TO THE EAST WHICH WILL ALLOW SOME COOLER
LOW LEVEL AIR TO FILTER IN FROM THE NORTHWEST. CONCERNS ON THE
COVERAGE OF PRECIPITATION GIVEN THE A SIGNIFICANT DRY LAYER FROM
850-700 MB...WHICH SHOULD CERTAINLY MAKE FOR A GENERALLY DRY MORNING
PRECIPITATION WISE OTHER THAN SOME DRIZZLE OR SOME LIGHT RAIN SOUTH
AND EAST OF THE LOW THERMAL COLD FRONTAL BOUNDARY. THIS WOULD FAVOR
I-55 AND SOUTHEASTWARD. FORECAST SOUNDINGS SUGGEST A PRETTY
SIGNIFICANT LOW LEVEL WARM NOSE WILL BE ERODING
THROUGH THE AFTERNOON DURING THE HIGHEST LIKELIHOOD PERIOD FOR
PRECIPITATION...BUT EVEN THIS PERIOD OF TIME HI-RES MODELS ARE NOT
EXCITED ABOUT WIDESPREAD PRECIPITATION...DESPITE GLOBAL MODELS
PAINTING A FEW HUNDREDTHS OF PRECIPITATION AREA-WIDE. HAVE GENERALLY
CARRIED HIGH CHANCE POPS FOR THE AFTERNOON PERIOD WHEN WE WOULD HAVE
A BETTER CHANCE FOR DEEPER SATURATION. MOST AREAS EXCEPT IN THE
NORTHWEST SHOULD REMAIN ABOVE FREEZING FOR ALL RAIN DURING THE DAY.
A LITTLE COLDER AIR FILTERS INTO THE AREA SUNDAY NIGHT AS THE UPPER
TROUGH MOVES EAST AND THE SURFACE LOW HEADS TOWARD THE ATLANTIC
SEABOARD. NORTH/NORTHEAST FLOW SETS UP DOWN THE LAKE FOR A DECENT
PERIOD OF TIME...WHICH IS CERTAINLY FAVORABLE FOR LAKE EFFECT SNOW
SHOWERS. THE AIR MASS THIS TIME IS NOT QUITE AS COLD IN THE LOW
LEVEL CLOUD LAYER...SUGGESTING THAT SNOW PRODUCTION WOULD BE LESS
THAN IDEAL. BUT INVERSION HEIGHTS AND LAPSE RATES DO GET BETTER LATE
SUNDAY NIGHT AND INTO MONDAY. STILL...EVEN GLOBAL MODELS SPIT OUT
SOME QPF OVER NORTHEAST ILLINOIS OVERNIGHT INTO MONDAY MORNING...AND
A CONVERGENCE SIGNAL HANGING ON INTO NORTHWEST INDIANA THROUGH
MONDAY AFTERNOON. IN REALITY...THIS SIGNAL HANGS ON EVEN OVERNIGHT
FOR NW INDIANA WHERE LIGHT LAKE EFFECT SNOWS MAY
STILL CONTINUE. 850-700 RH IS DISSIPATING ALL THE WHILE ELSEWHERE...CLOUDS
MAY BE A LITTLE SLOWER TO CLEAR AS WE REMAIN IN CYCLONIC FLOW ALOFT
AND HIGH PRESSURE STILL LINGERS TO THE WEST. BUT MOST AREAS AWAY
FROM THE LAKE DRY OUT FAIRLY QUICKLY...ESPECIALLY OVERNIGHT INTO
MONDAY MORNING.
KMD
&&
.LONG TERM...
212 PM CST
MONDAY NIGHT THROUGH SATURDAY...
SURFACE HIGH PRESSURE BUILDS IN WITH A BIT MORE GUSTO ON MONDAY
NIGHT INTO TUESDAY...THOUGH HIGH CLOUDS WILL BE INCREASING THROUGH
THE DAY SOME MODEL DISAGREEMENT AS TO HOW MUCH THIS WAVE WILL
INTERACT WITH A MORE SIGNIFICANT UPPER TROUGH OF PACIFIC ORIGIN BUT
MUCH FARTHER NORTH...AND WILL PUSH SOUTHEAST THROUGH THE CANADIAN
PRAIRIES TOWARD OUR REGION LATER WEDNESDAY. IT LOOKS LIKE A PERIOD
OF LIGHT PRECIPITATION TUESDAY NIGHT INTO WEDNESDAY...WITH THE BEST
CHANCES I-88 NORTHWARD. PROFILES AT THIS POINT SUGGEST SNOW/SLEET
TRANSITIONING TO ALL SNOW. IF THE PRECIP GETS SOUTH OF I-80...IT
WOULD TRANSITION TO A RAIN/SNOW MIX ON WEDS.
ANOTHER GOOD SLUG OF COLD AIR WILL BE HEADING OUR WAY WITH THIS COLD
PUSH...ALONG WITH SOME DECENT WINDS. THE SURFACE WAVE IS NOT VERY
DEEP ASSOCIATED WITH THE TROUGH AND THE BETTER PRESSURE FALLS LOOK
TO REMAIN TO THE NORTH...BUT IT IS A PRETTY STRONG HIGH PROGGED TO
MOVE EASTWARD. WHILE EARLY THURSDAY WILL BE COLD AND WINDY...THE
HIGH MOVES OVERHEAD LATE THURSDAY AND THURSDAY NIGHT. WHILE WARM
ADVECTING....CLEAR SKIES AND LIGHT WINDS WILL MAKE FOR ANOTHER COLD
NIGHT THURSDAY NIGHT AND MORNING EARLY FRIDAY.
THE NEXT CHANCE FOR SNOW WOULD BE NEXT WEEKEND AS POTENTIAL
CROSS-POLAR FLOW ALOFT SETS UP AND MAY BRING ANOTHER COLD FRONT
THROUGH.
KMD
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* IFR STRATUS WILL SLOWLY DEVELOP...MAINLY AFTER 10Z. THEN PERSIST
THRU MIDDAY SUNDAY.
* PATCHY FOG WILL SPREAD IN COVERAGE OVERNIGHT...REDUCING VSBYS TO
MVFR AND POSSIBLY FURTHER TOWARDS IFR VSBYS JUST BEFORE DAYBREAK
AND LINGER THRU MID-MORNING.
* WINDS LIGHT FROM THE SOUTH/SOUTHWEST AND MAY BECOME CALM EARLY
THIS MORNING. WINDS THEN QUICKLY TURN NORTHWEST THEN JUST EAST
OF NORTH AT 010 DEG AFTER 21Z.
* DRIZZLE MAY BEGIN TO DEVELOP...BUT SHOULD BE PATCHY. A FEW
SHOWERS ARE POSSIBLE AFT 21Z BUT LIMITED COVERAGE AND LIGHT
INTENSITY.
BEACHLER
//DISCUSSION...UPDATED 06Z...
IR IMAGERY CONTINUES TO SHOW A CIRRUS DECK SLIDING ACROSS THE
REGION...WITH SURFACE OBS NOT INDICATING ANY STARTUS AT THIS TIME.
SOME REDUCED VSBYS ARE BEGINNING TO DEVELOP ACROSS NORTHERN IL
AIRFIELDS...WITH MANY SITES WEST OF ORD/MDW ALREADY REDUCED TO
2-3SM. EXPECT AS TEMPERATURES SLOWLY FALL...ADDTL SITES WILL SEE
VSBYS REDUCED. AIRFIELDS WEST OF ORD/MDW WILL LIKELY SEE FOG BRING
VSBYS DOWN TO AROUND 1SM BY 10-11Z...AND ORD/MDW WILL BE DOWN TO
2-3SM. MEANWHILE GUIDANCE CONTINUES TO SUGGEST SOME STRATUS CLOUDS
WILL DEVELOP...AND SPREAD IN COVERAGE OVERNIGHT. ONCE THE
FOG/STRATUS DEVELOP...CONDITIONS SHOULD REMAIN REDUCED THROUGH
MID-MORNING. AS A LOW PRESSURE SYSTEM SLIDES OVERHEAD...WINDS WILL
BRIEFLY BECOME CALM FROM THE CURRENT LGT SOUTH/SOUTHWEST SETUP.
THEN WINDS WILL TURN NORTHWEST BUT REMAIN LGT OR LESS THAN 8KT. A
FRONTAL BOUNDARY WILL DRIVE SOUTH ACROSS THE AREA THIS
AFTERNOON...BRINGING WINDS QUICKLY TO THE NORTH AND SLIGHTLY
NORTHEAST ALONG WITH SPEEDS INCREASING TO ARND 10KT AND GUSTS
NEARING 16-18KT. WITH BETTER MIXING ARRIVING LATER THIS AFTN/EARLY
EVE...THE STRATUS DECK AND REDUCED VSBYS SHUD BEGIN TO IMPROVE
SLIGHTLY.
SOME PATCHY DRIZZLE MAY ALSO DEVELOP PRIOR TO THE ARRIVAL OF THE
LOW PRESSURE SYSTEM...WITH A FEW LIGHT RAIN SHOWERS LATER THIS
AFTERNOON. BUT GIVEN THE CONFIDENCE IN THIS PLAYING OUT HAVE OPTED
TO HOLD OFF ON MENTION OF DRIZZLE AS THEIR REMAINS AN ABUNDANCE OF
DRY AIR ALOFT...AND COVERAGE FOR SHOWERS LOOKS TO REMAIN MINIMAL
AND WILL CARRY VCSH AT THIS TIME.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM-HIGH IN IFR CIGS SUNDAY MORNING. LOW-MEDIUM IN REACHING
LIFR. LOW-MEDIUM IN START TIME AND DURATION.
* LOW-MEDIUM IN IFR VISIBILITY SUNDAY MORNING AND DURATION OF FOG.
* MEDIUM-HIGH IN WINDS TURNING NORTH-NORTHEAST ON SUNDAY AFTERNOON
AND PERSISTING INTO SUNDAY NIGHT.
* LOW-MEDIUM ON PRECIPITATION CHANCES BUT HIGH THAT IF ANY OCCURS
PRIOR TO 21Z SUNDAY IT WILL BE LIGHT AND LIQUID.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...MVFR AND A CHANCE FOR LIGHT SNOW IN THE MORNING. NORTH
WINDS.
TUESDAY...MVFR DURING THE NIGHT WITH POSSIBLE IFR. CHANCE OF SNOW
OR SLEET. SOUTHEAST WINDS.
WEDNESDAY...MVFR WITH IFR POSSIBLE. CHANCE OF SNOW. NORTHWEST
WINDS.
THURSDAY...VFR. NORTHWEST WINDS.
FRIDAY...MVFR POSSIBLE. CHANCE OF SNOW DURING THE NIGHT. SOUTHWEST
WINDS.
MTF
&&
.MARINE...
202 AM CST
A FRONTAL BOUNDARY REMAINS ACROSS THE NORTHERN SECTIONS OF THE LAKE
EARLY THIS MORNING...AND WILL SAG SOUTH THROUGH THE DAY. AS A LOW
PRESSURE SYSTEM APPROACHES LAKE MICHIGAN THIS AFTERNOON...THE FRONT
WILL BEGIN TO SLIDE SOUTH FASTER AND REACH THE SOUTHERN TIP OF LAKE
MICHIGAN LATE THIS AFTERNOON. WINDS TO THE NORTH OF THE BOUNDARY
HAVE INCREASED AS A RESULT OF THE TIGHTER GRADIENT...GUSTING TO 25KT
AT TIMES. FURTHER SOUTH THE SOUTHERLY WINDS HAVE PERSISTED BETWEEN
10-20KT. AS THE TIGHTER GRADIENT SLIDES SOUTH THIS AFTERNOON...WINDS
WILL QUICKLY TURN NORTH/NORTHEAST AND INCREASE TO 20-25KT. THIS WILL
LIKELY CREATE HAZARDOUS WINDS TO SMALL CRAFT BY MID-AFTERNOON FOR
THE NORTHERN IL NEARSHORE WATERS. VISIBLE SATELLITE IMAGERY FROM SUN
INDICATES CONSIDERABLE ICE COVERAGE REMAINS. AT THIS TIME HAVE OPTED
TO KEEP MENTION OF WAVES OUT OF THE NEARSHORE PRODUCT BUT MAY NEED
TO ADD WAVES BACK IN DEPENDING ON HOW EXTENSIVE THE ICE IS LATER
TODAY.
WITH COLDER AIR SLIDING SOUTH BEHIND THE FRONTAL BOUNDARY...WINDS
MAY AT TIMES GUST TO 30KT THIS EVENING. BUT EXPECT THE BULK OF THE
WINDS TO BE BETWEEN 20-25KT. HIGH PRESSURE BUILDS IN FROM THE WEST
MONDAY AND WILL BRING A STEADY DECREASE IN THE GRADIENT AND LIGHTER
WINDS. HIGH PRESSURE QUICKLY SLIDES EAST TUESDAY WITH YET ANOTHER
LOW PRESSURE SYSTEM ARRIVING. WINDS WILL TURN SOUTHERLY AHEAD OF THE
NEXT LOW PRESSURE...BEFORE TURNING WEST TO NORTH BEHIND A COLD FRONT
WEDNESDAY. THE NEXT CHANCE FOR GALES APPEARS TO BE BEHIND THE FRONT
WEDNESDAY NIGHT INTO THURSDAY AS VERY STRONG HIGH PRESSURE BUILDS
FRONT THE CANADIAN PRAIRIES INTO THE UPPER MIDWEST.
BEACHLER
&&
.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
NWS CHICAGO/ROMEOVILLE IL
1158 PM CST SAT FEB 7 2015
.UPDATE...942 PM CST
IT APPEARS THE THREAT OF LOW CLOUD DEVELOPMENT FOR MUCH OF THE
NIGHT WILL BE LOW. THE 00 UTC SOUNDING OUT OF KDVN IS VERY DRY
ABOVE 900 MB. MUCH OF THE LOWER CLOUD COVER CONTINUES TO BE
CONFINED NORTH OF THE SURFACE BOUNDARY OVER WISCONSIN.
THEREFORE...LOWER CLOUD COVER (OUTSIDE OF FOG DEVELOPMENT) DOES
NOT APPEAR LIKELY UNTIL SUNDAY MORNING AS THE COLDER AIR MASS TO
OUR NORTH BEGINS TO SAG BACK SOUTHWARD OVER NORTHERN ILLINOIS
FOLLOWING THE PASSAGE FOR THE SURFACE LOW. WITH ALL THIS IN
MIND...IT APPEARS THAT FOG DEVELOPMENT MAY END UP BEING THE
PRIMARY CONCERN OVERNIGHT...ESPECIALLY ACROSS NORTH CENTRAL
ILLINOIS WHERE TEMPERATURES HAVE COOLED INTO THE LOWER 30S. WITH
THE SURFACE LOW EXPECTED TO SHIFT RIGHT OVER NORTHERN ILLINOIS
LATE TONIGHT...LIGHT WINDS AND ABUNDANT NEAR SURFACE MOISTURE
SHOULD LEAD TO FOG...WITH THE POTENTIAL FOR SOME DENSE FOG.
I HAVE REMOVED THE MENTION OF DRIZZLE/FREEZING DRIZZLE OVERNIGHT
AS IT APPEARS TO BE LESS OF THREAT GIVEN THE LACK OF LOW LEVEL
CLOUDINESS.
KJB
&&
.SHORT TERM...
212 PM CST
THROUGH MONDAY...
CONCERNS AROUND FOG POTENTIAL TONIGHT...LOCALLY DENSE...MIXED
PRECIPITATION TURNING TO SNOW LATER SUNDAY INTO SUNDAY NIGHT.
WARM FRONT WHICH WAS BISECTING PORTIONS OF THE AREA TODAY IS NOW
LIFTING NORTHWARD. TEMPERATURES AREA WIDE HAVE REACHED THE UPPER 30S
TO LOW 40S AREA WIDE. WE HAVE A FEW STRAGGLER COLD SPOTS LIKE
ROCHELLE AND DEKALB THAT HAVE TRAILED BEHIND DUE TO SOME LINGERING
FOG. HIGH CLOUDS SHOULD LIMIT THE WARMING TREND THROUGH THE
AFTERNOON.
MODELS ARE STILL INSISTENT ON BREAKING OUT LOW CLOUDS AND ADDITIONAL
FOG LATE THIS AFTERNOON AND TONIGHT. DEWPOINTS NOW IN THE 30S...SO
CHANCES ARE INCREASING. RAP MODEL WHICH HAS HAD THE
MOST SUCCESS IN THIS REGIME ALONG WITH MOS GUIDANCE SUGGEST THAT IT
WILL STILL TAKE SOME TIME FOR CLOUDS AND FOG TO BECOME MORE
SOLIDIFIED. WILL STILL SEE SOME PATCHY FOG OR HAZE THIS EVENING...BUT
BETTER CHANCES COME OVERNIGHT...AS BETTER PERFORMING MOS GUIDANCE
SUGGESTS. WITH THE SURFACE LOW MOVING OVERHEAD...WINDS WILL
SLACKEN AND THUS AREAS FROM I-80 NORTHWARD STAND A BETTER CHANCE
FOR FOG DEVELOPMENT TONIGHT...LOCALLY DENSE. THERE IS A WEAK WAVE
IN THE WESTERLY FLOW ALOFT...AND IF WE ARE SATURATED
DOWNSTAIRS...THERE IS SOME WEAK TO MAYBE MODERATE LIFT IN THE LOW
LAYERS...INITIALLY ISENTROPIC UPGLIDE...THEN SOME VERY LOW
FRONTOGENETICAL FORCING THE AS THE 925 MB BOUNDARY BEGINS TO SINK
SOUTHEASTWARD. THAT COULD LEAD TO A LITTLE DRIZZLE OUT OF THE
STRATUS OVERNIGHT. GIVEN THE LACK OF STRATUS THUS FAR...NOT
EXPECTING A WHOLE LOT OF COVERAGE. DEWPOINTS ARE FORECAST TO BE
ABOVE FREEZING EXCEPT FOR MAYBE ALONG FAR NORTHERN ILLINOIS. WITH
THE NAM/RAP/SREF TRACKING THE SURFACE LOW THROUGH NORTHERN
ILLINOIS INSTEAD OF THROUGH CENTRAL ILLINOIS...BELIEVE THE MOST
AREAS SHOULD BE ABOVE FREEZING OVERNIGHT IF ANY PRECIPITATION IS
OCCURRING...EVEN THOUGH TEMPS IN NORTH CENTRAL ILLINOIS MAY DIP TO
FREEZING OR SO LATE TONIGHT.
ON SUNDAY THE SOUTHERN SHORTWAVE IS PROGGED TO MOVE THROUGH THE
AREA...MAINLY DURING THE LATER MORNING AND AFTERNOON. THE ASSOCIATED
SURFACE LOW WILL BE PASSING TO THE EAST WHICH WILL ALLOW SOME COOLER
LOW LEVEL AIR TO FILTER IN FROM THE NORTHWEST. CONCERNS ON THE
COVERAGE OF PRECIPITATION GIVEN THE A SIGNIFICANT DRY LAYER FROM
850-700 MB...WHICH SHOULD CERTAINLY MAKE FOR A GENERALLY DRY MORNING
PRECIPITATION WISE OTHER THAN SOME DRIZZLE OR SOME LIGHT RAIN SOUTH
AND EAST OF THE LOW THERMAL COLD FRONTAL BOUNDARY. THIS WOULD FAVOR
I-55 AND SOUTHEASTWARD. FORECAST SOUNDINGS SUGGEST A PRETTY
SIGNIFICANT LOW LEVEL WARM NOSE WILL BE ERODING
THROUGH THE AFTERNOON DURING THE HIGHEST LIKELIHOOD PERIOD FOR
PRECIPITATION...BUT EVEN THIS PERIOD OF TIME HI-RES MODELS ARE NOT
EXCITED ABOUT WIDESPREAD PRECIPITATION...DESPITE GLOBAL MODELS
PAINTING A FEW HUNDREDTHS OF PRECIPITATION AREA-WIDE. HAVE GENERALLY
CARRIED HIGH CHANCE POPS FOR THE AFTERNOON PERIOD WHEN WE WOULD HAVE
A BETTER CHANCE FOR DEEPER SATURATION. MOST AREAS EXCEPT IN THE
NORTHWEST SHOULD REMAIN ABOVE FREEZING FOR ALL RAIN DURING THE DAY.
A LITTLE COLDER AIR FILTERS INTO THE AREA SUNDAY NIGHT AS THE UPPER
TROUGH MOVES EAST AND THE SURFACE LOW HEADS TOWARD THE ATLANTIC
SEABOARD. NORTH/NORTHEAST FLOW SETS UP DOWN THE LAKE FOR A DECENT
PERIOD OF TIME...WHICH IS CERTAINLY FAVORABLE FOR LAKE EFFECT SNOW
SHOWERS. THE AIR MASS THIS TIME IS NOT QUITE AS COLD IN THE LOW
LEVEL CLOUD LAYER...SUGGESTING THAT SNOW PRODUCTION WOULD BE LESS
THAN IDEAL. BUT INVERSION HEIGHTS AND LAPSE RATES DO GET BETTER LATE
SUNDAY NIGHT AND INTO MONDAY. STILL...EVEN GLOBAL MODELS SPIT OUT
SOME QPF OVER NORTHEAST ILLINOIS OVERNIGHT INTO MONDAY MORNING...AND
A CONVERGENCE SIGNAL HANGING ON INTO NORTHWEST INDIANA THROUGH
MONDAY AFTERNOON. IN REALITY...THIS SIGNAL HANGS ON EVEN OVERNIGHT
FOR NW INDIANA WHERE LIGHT LAKE EFFECT SNOWS MAY
STILL CONTINUE. 850-700 RH IS DISSIPATING ALL THE WHILE ELSEWHERE...CLOUDS
MAY BE A LITTLE SLOWER TO CLEAR AS WE REMAIN IN CYCLONIC FLOW ALOFT
AND HIGH PRESSURE STILL LINGERS TO THE WEST. BUT MOST AREAS AWAY
FROM THE LAKE DRY OUT FAIRLY QUICKLY...ESPECIALLY OVERNIGHT INTO
MONDAY MORNING.
KMD
&&
.LONG TERM...
212 PM CST
MONDAY NIGHT THROUGH SATURDAY...
SURFACE HIGH PRESSURE BUILDS IN WITH A BIT MORE GUSTO ON MONDAY
NIGHT INTO TUESDAY...THOUGH HIGH CLOUDS WILL BE INCREASING THROUGH
THE DAY SOME MODEL DISAGREEMENT AS TO HOW MUCH THIS WAVE WILL
INTERACT WITH A MORE SIGNIFICANT UPPER TROUGH OF PACIFIC ORIGIN BUT
MUCH FARTHER NORTH...AND WILL PUSH SOUTHEAST THROUGH THE CANADIAN
PRAIRIES TOWARD OUR REGION LATER WEDNESDAY. IT LOOKS LIKE A PERIOD
OF LIGHT PRECIPITATION TUESDAY NIGHT INTO WEDNESDAY...WITH THE BEST
CHANCES I-88 NORTHWARD. PROFILES AT THIS POINT SUGGEST SNOW/SLEET
TRANSITIONING TO ALL SNOW. IF THE PRECIP GETS SOUTH OF I-80...IT
WOULD TRANSITION TO A RAIN/SNOW MIX ON WEDS.
ANOTHER GOOD SLUG OF COLD AIR WILL BE HEADING OUR WAY WITH THIS COLD
PUSH...ALONG WITH SOME DECENT WINDS. THE SURFACE WAVE IS NOT VERY
DEEP ASSOCIATED WITH THE TROUGH AND THE BETTER PRESSURE FALLS LOOK
TO REMAIN TO THE NORTH...BUT IT IS A PRETTY STRONG HIGH PROGGED TO
MOVE EASTWARD. WHILE EARLY THURSDAY WILL BE COLD AND WINDY...THE
HIGH MOVES OVERHEAD LATE THURSDAY AND THURSDAY NIGHT. WHILE WARM
ADVECTING....CLEAR SKIES AND LIGHT WINDS WILL MAKE FOR ANOTHER COLD
NIGHT THURSDAY NIGHT AND MORNING EARLY FRIDAY.
THE NEXT CHANCE FOR SNOW WOULD BE NEXT WEEKEND AS POTENTIAL
CROSS-POLAR FLOW ALOFT SETS UP AND MAY BRING ANOTHER COLD FRONT
THROUGH.
KMD
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* IFR STRATUS WILL SLOWLY DEVELOP...MAINLY AFTER 10Z. THEN PERSIST
THRU MIDDAY SUNDAY.
* PATCHY FOG WILL SPREAD IN COVERAGE OVERNIGHT...REDUCING VSBYS TO
MVFR AND POSSIBLY FURTHER TOWARDS IFR VSBYS JUST BEFORE DAYBREAK
AND LINGER THRU MID-MORNING.
* WINDS LIGHT FROM THE SOUTH/SOUTHWEST AND MAY BECOME CALM EARLY
THIS MORNING. WINDS THEN QUICKLY TURN NORTHWEST THEN JUST EAST
OF NORTH AT 010 DEG AFTER 21Z.
* DRIZZLE MAY BEGIN TO DEVELOP...BUT SHOULD BE PATCHY. A FEW
SHOWERS ARE POSSIBLE AFT 21Z BUT LIMITED COVERAGE AND LIGHT
INTENSITY.
BEACHLER
//DISCUSSION...UPDATED 06Z...
IR IMAGERY CONTINUES TO SHOW A CIRRUS DECK SLIDING ACROSS THE
REGION...WITH SURFACE OBS NOT INDICATING ANY STARTUS AT THIS TIME.
SOME REDUCED VSBYS ARE BEGINNING TO DEVELOP ACROSS NORTHERN IL
AIRFIELDS...WITH MANY SITES WEST OF ORD/MDW ALREADY REDUCED TO
2-3SM. EXPECT AS TEMPERATURES SLOWLY FALL...ADDTL SITES WILL SEE
VSBYS REDUCED. AIRFIELDS WEST OF ORD/MDW WILL LIKELY SEE FOG BRING
VSBYS DOWN TO AROUND 1SM BY 10-11Z...AND ORD/MDW WILL BE DOWN TO
2-3SM. MEANWHILE GUIDANCE CONTINUES TO SUGGEST SOME STRATUS CLOUDS
WILL DEVELOP...AND SPREAD IN COVERAGE OVERNIGHT. ONCE THE
FOG/STRATUS DEVELOP...CONDITIONS SHOULD REMAIN REDUCED THROUGH
MID-MORNING. AS A LOW PRESSURE SYSTEM SLIDES OVERHEAD...WINDS WILL
BRIEFLY BECOME CALM FROM THE CURRENT LGT SOUTH/SOUTHWEST SETUP.
THEN WINDS WILL TURN NORTHWEST BUT REMAIN LGT OR LESS THAN 8KT. A
FRONTAL BOUNDARY WILL DRIVE SOUTH ACROSS THE AREA THIS
AFTERNOON...BRINGING WINDS QUICKLY TO THE NORTH AND SLIGHTLY
NORTHEAST ALONG WITH SPEEDS INCREASING TO ARND 10KT AND GUSTS
NEARING 16-18KT. WITH BETTER MIXING ARRIVING LATER THIS AFTN/EARLY
EVE...THE STRATUS DECK AND REDUCED VSBYS SHUD BEGIN TO IMPROVE
SLIGHTLY.
SOME PATCHY DRIZZLE MAY ALSO DEVELOP PRIOR TO THE ARRIVAL OF THE
LOW PRESSURE SYSTEM...WITH A FEW LIGHT RAIN SHOWERS LATER THIS
AFTERNOON. BUT GIVEN THE CONFIDENCE IN THIS PLAYING OUT HAVE OPTED
TO HOLD OFF ON MENTION OF DRIZZLE AS THEIR REMAINS AN ABUNDANCE OF
DRY AIR ALOFT...AND COVERAGE FOR SHOWERS LOOKS TO REMAIN MINIMAL
AND WILL CARRY VCSH AT THIS TIME.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM-HIGH IN IFR CIGS SUNDAY MORNING. LOW-MEDIUM IN REACHING
LIFR. LOW-MEDIUM IN START TIME AND DURATION.
* LOW-MEDIUM IN IFR VISIBILITY SUNDAY MORNING AND DURATION OF FOG.
* MEDIUM-HIGH IN WINDS TURNING NORTH-NORTHEAST ON SUNDAY AFTERNOON
AND PERSISTING INTO SUNDAY NIGHT.
* LOW-MEDIUM ON PRECIPITATION CHANCES BUT HIGH THAT IF ANY OCCURS
PRIOR TO 21Z SUNDAY IT WILL BE LIGHT AND LIQUID.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...MVFR AND A CHANCE FOR LIGHT SNOW IN THE MORNING. NORTH
WINDS.
TUESDAY...MVFR DURING THE NIGHT WITH POSSIBLE IFR. CHANCE OF SNOW
OR SLEET. SOUTHEAST WINDS.
WEDNESDAY...MVFR WITH IFR POSSIBLE. CHANCE OF SNOW. NORTHWEST
WINDS.
THURSDAY...VFR. NORTHWEST WINDS.
FRIDAY...MVFR POSSIBLE. CHANCE OF SNOW DURING THE NIGHT. SOUTHWEST
WINDS.
MTF
&&
.MARINE...
221 PM CST
A STATIONARY FRONTAL BOUNDARY IS DRAPED ACROSS CENTRAL LAKE
MICHIGAN TODAY WITH MODERATE EAST TO NORTHEAST WINDS PUSHING 30
KT AT TIMES ACROSS NORTHERN PORTIONS OF LAKE MICHIGAN AND MORE
MODEST SOUTH TO SOUTHWEST WINDS ACROSS THE SOUTHERN HALF OF THE
LAKE. WITHIN THE SOUTHERLY FLOW...WARMER DEWPOINTS ADVECTING OVER
THE LAKE THIS EVENING AND TONIGHT MAY CAUSE FOG TO BECOME MORE
WIDESPREAD AND DENSE. A WAVE DEVELOPING ALONG THE FRONTAL BOUNDARY
WILL MOVE ACROSS THE LAKE LATE TONIGHT WITH NORTHERLY FLOW
SPREADING DOWN THE LAKE SUNDAY. HIGH PRESSURE WILL MOVE OVER THE
LAKE MONDAY NIGHT...THEN SOUTHERLY FLOW FRESHENS UP TUESDAY AS A
CLIPPER MOVES ACROSS THE NORTHERN LAKES REGION PUSHING A COLD
FRONT ACROSS LAKE MICHIGAN ON WEDNESDAY. THE NEXT GOOD CHANCE FOR
GALES APPEARS TO BE BEHIND THE FRONT WEDNESDAY NIGHT INTO THURSDAY
AS VERY STRONG HIGH PRESSURE BUILDS FRONT THE CANADIAN PRAIRIES
INTO THE UPPER MIDWEST.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS DES MOINES IA
530 PM CST MON FEB 9 2015
...UPDATED AVIATION DISCUSSION...
.SHORT TERM /TONIGHT/...
ISSUED AT 328 PM CST MON FEB 9 2015
MAIN CONCERNS ARE CLOUD COVER AND APPROACHING WAVE FROM THE WEST.
LOW STRATUS ERODING OVER THE NORTH MOMENTARILY BUT SHOULD BEGIN TO
FILL BACK IN AFTER SUNSET. THE HRRR SHOWS THE CURRENT SETUP QUITE
WELL WITH SOME THINNING OF THE CLOUD DECK OVER THE NORTH FOLLOWED
BY CLOUDS FILLING IN ONCE AGAIN. THE UPSTREAM SHORT WAVE OVER MT
WILL MOVE SOUTHEAST OVERNIGHT AND SHOULD BEGIN TO IMPACT THE
NORTHWEST WITH PRECIPITATION CHANCES BETWEEN 09-12Z. BUFR
SOUNDINGS OVER THE NORTHWEST SHOW LOWER LAYERS THICKENING TOWARD
MORNING WITH SOME LIFT INCREASING TOWARD 12Z. WILL MAINTAIN LIGHT
FREEZING DRIZZLE ACROSS THE NORTHWEST TRANSITIONING TO A CHANCE
FOR LIGHT FREEZING DRIZZLE OR LIGHT FREEZING RAIN/ICE PELLET MIX
BY 12Z. INITIALLY THERE IS NOT MUCH IN THE WAY OF ICE INTRODUCTION
WHICH WOULD FAVOR SOME LIGHT FREEZING DRIZZLE. TEMPERATURES
TONIGHT ARE CHALLENGING AS WELL. GUIDANCE DROPS VALUES INTO THE
TEENS NORTH TO LOWER TO MID 20S MOST AREAS. LAST NIGHT MOIST
BOUNDARY LAYER AND CLOUD COVER KEPT MINS IN THE LOWER 30S. THOUGH
NOT EXPECTING IT TO BE THAT WARM TONIGHT THERE SHOULD BE A DECENT
GRADIENT FROM EAST TO SOUTHWEST WITH UPPER TEENS EAST TO THE MID
TO UPPER 20S OVER THE SOUTHWEST WHERE CLOUDS WILL HOLD.
.LONG TERM /TUESDAY THROUGH MONDAY/...
ISSUED AT 328 PM CST MON FEB 9 2015
LITTLE HAS CHANGED IN OVERALL FORECAST THINKING FROM PREVIOUS
SHIFTS. A LOW PRESSURE SYSTEM WILL SPREAD PRECIPITATION ACROSS
MOST OF MINNESOTA ON TUESDAY...WITH LIGHT PRECIPITATION AFFECTING
NORTHERN IOWA...THEN PUSH A PRETTY STRONG COLD FRONT ACROSS IOWA
ON TUESDAY NIGHT AND WEDNESDAY MORNING. THE PRECIPITATION ACROSS
NORTHERN IOWA STILL LOOKS SPOTTY AND VERY LIGHT...WITH FORECAST
SOUNDINGS SHOWING CLOUD DEPTHS WAVERING BETWEEN ABOUT 3000 AND
8000 FEET AND MAINLY LOCATED BENEATH BOTH THE ICE INTRODUCTION
LAYER AND THE LIMITED FORCING ASSOCIATED WITH THE LOW PASSING BY
TO THE NORTH. THIS SUPPORTS MOSTLY A DRIZZLE/LIGHT RAIN SCENARIO
WITH TEMPERATURES NEAR OR A LITTLE BELOW FREEZING...LIKELY LEADING
TO SOME LIGHT ICE ACCUMULATIONS OF PERHAPS A FEW HUNDREDTHS OF AN
INCH. GIVEN THE RELATIVELY LOW CONFIDENCE IN ACCUMULATING
PRECIPITATION OCCURRING IN OUR AREA...WITH ONLY 40 TO 50 POPS IN
THE NORTH AND VERY LIGHT EXPECTED AMOUNTS...HAVE NOT ISSUED AN
ADVISORY AT THIS TIME. HOWEVER...THIS WILL BE CLOSELY MONITORED
TONIGHT AND TOMORROW AND ONE MAY YET BECOME WARRANTED IF THERE IS
A MORE CONSISTENT SIGNAL FOR MEANINGFUL ICE ACCUMULATION/IMPACTS.
THE LIGHT PRECIPITATION ACROSS THE NORTH WILL END ON TUESDAY
NIGHT...THEN THE AFOREMENTIONED COLD FRONT WILL SWEEP RAPIDLY
SOUTHEASTWARD ACROSS THE AREA. WINDS WILL SURGE SIGNIFICANTLY ON
WEDNESDAY MORNING...THEN AGAIN ON WEDNESDAY EVENING AS ONE LAST
500 MB IMPULSE ROUNDS THE TROUGH AND IS REFLECTED BY A TIGHTENING
SURFACE PRESSURE GRADIENT. FORECAST SOUNDINGS INDICATE WINDS AT
THE TOP OF THE MIXED LAYER APPROACHING 40 KNOTS AT TIMES AND THERE
IS AN INCREASING POSSIBILITY...ESPECIALLY GIVEN THE COLD AIR
ADVECTION AND EFFICIENT MIXING EXPECTED...THAT A WIND ADVISORY MAY
BECOME NECESSARY AT SOME POINT FOR WEDNESDAY INTO WEDNESDAY NIGHT.
TEMPERATURES WILL LIKELY REMAIN STEADY OR FALL DURING THE DAY
WEDNESDAY...THEN PLUMMET FURTHER WEDNESDAY NIGHT WITH WIND CHILLS
OF AROUND 20 TO 25 BELOW FORECAST ACROSS NORTHERN IOWA BY THURSDAY
MORNING.
AS A SURFACE HIGH PRESSURE AREA CROSSES IOWA ON THURSDAY WINDS
WILL LIGHTEN SUBSTANTIALLY BUT IT WILL REMAIN COLD...THEN WE WILL
CONTINUE THIS SERIES OF ALTERNATING HIGHS AND LOW PRESSURE TROUGHS
THROUGH THE WEEKEND. THIS WILL RESULT IN A MODEST WARM UP ON
FRIDAY...ANOTHER FRONTAL PASSAGE LATE FRIDAY...MORE STRONG WINDS
AROUND FRIDAY NIGHT INTO SATURDAY...MORE COLD ON SATURDAY AND
SATURDAY NIGHT...ETC. IN A REPEAT OF THE PATTERN WE HAVE SEEN FOR
THE LAST SEVERAL DAYS ALREADY. THERE IS SOME INDICATION IN THE
PAST SEVERAL RUNS OF THE ECMWF AND GFS THAT THIS PATTERN COULD
SHIFT A BIT FURTHER SOUTHWARD AROUND MONDAY OR TUESDAY OF NEXT
WEEK AS A BROAD 500 MB TROUGH DIGS A BIT FURTHER DOWN INTO THE
CENTRAL U.S. IF THIS VERIFIES THEN IT WOULD SPREAD THE BULK OF THE
PRECIPITATION FROM THE ASSOCIATED SURFACE SYSTEM MORE ACROSS IOWA
RATHER THAN FURTHER NORTH AS WE HAVE SEEN THUS FAR...HOWEVER AT
THIS RANGE IT IS WAY TOO EARLY TO GET MUCH DETAIL OUT OF WHAT THIS
WOULD MEAN FOR SENSIBLE WEATHER AND PRECIPITATION AMOUNTS ACROSS
CENTRAL IOWA.
&&
.AVIATION...10/00Z
ISSUED AT 527 PM CST MON FEB 9 2015
MVFR STRATUS LOOKS TO CONTINUE THROUGH TOMORROW WITH INTERMITTENT
BREAKS POSSIBLE...SUCH AS AROUND OTM AREA ATTM. EXPECTING THE
STRATUS SHIELD TO FILL BACK IN AT OTM. WINDS WILL INCREASE TUESDAY
MORNING AND TWEAKED UP SUSTAINED AND WIND GUST FOR ALL SITES.
FOD/MCW KEPT FREEZING PRECIP MENTIONED BUT DELAYED THE ONSET UNTIL
MID-MORNING TUESDAY. LEFT OUT MENTION AT ALO AS ANY PRECIP LOOKS
TO ENTER NORTHEAST IOWA PAST 18Z TUESDAY.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...REV
LONG TERM...LEE
AVIATION...PODRAZIK
AREA FORECAST DISCUSSION
NWS TOPEKA KS
901 PM CST Mon Feb 9 2015
...Updated for fog potential...
.UPDATE...
Issued at 825 PM CST MON FEB 9 2015
Have issued a dense fog advisory for Cloud and Republic counties.
Observations in this region have shown visibilities from 1/4 up to
1 mile, with area law enforcement reporting that the visibility
has been generally decreasing. With ceilings only 100 to 200 feet
AGL, this appears to be a favorable situation for dense fog to
develop, and recent model guidance suggested the same. Of interest
is an area of drier air moving into this region from the
southeast, which may act to dissipate fog if it can move into
these counties so will need to keep an eye on that.
In the next several hours, there is also potential for the area of
clear skies to have fog develop within it as dewpoint depressions
are only 1 to 3 degrees while temperatures are dropping off
quickly. Initially, low level winds may be weak enough to allow
radiation fog, but as low level winds turn out of the southeast in
these areas, neutral to moist advection into the cool air may
promote additional fog development.
&&
.SHORT TERM...(This Evening through Tuesday)
Issued at 343 PM CST MON FEB 9 2015
Surface high pressure ridge extends southeast across eastern Kansas
from Minnesota. Cool east to northeast flow along with stratus which
has held on most of the day, has kept temperatures from rising much
from morning lows especially across north central Kansas.
Latest visible satellite loop shows the stratus breaking up from
central Missouri into east central Kansas. HRRR, NAM and RAP show
some semblance of this trend for partial clearing from Emporia to
Topeka along with some further clearing this evening into northeast
Kansas. Areas of north central Kansas look to stay in the stratus
tonight. The low clouds may reform later tonight across the east.
Areas of fog are likely for much of the area overnight. Lows tonight
will vary due to breaks in the clouds. Expecting lows in the upper
20s to low to mid 30s.
Thermal axis noses into northeast Kansas on Tuesday ahead of the
next shortwave and surface frontal boundary. Forecast soundings show
mixing to 925mb to 900mb in the afternoon. Stratus looks to break up
in the late morning and early afternoon hours. Highs will range from
the 50s to around 60.
.LONG TERM...(Tuesday Night through Monday)
Issued at 343 PM CST MON FEB 9 2015
Next cold front still on track to move through the county warning
area (cwa) Tuesday night as a weak shortwave trough extending from
the Great Lakes into the southwest CONUS moves through and shears
with time. The initial push of cooler air will lower highs into the
upper 30s and lower 40s for Wednesdays and should move through the
area dry as well.
As the stronger secondary d cold front moves through late
Wednesday/Wednesday night...a much colder push of air will
overspread the area. The GFS is deeper with the eastern trough and
colder than the EC. Following lows in the teens and lower 20s
Thursday morning...highs will struggle to reach the 20s and lower
30s most areas. Again...with only weak forcing and limited
moisture...will maintain a dry fcst.
The upper ridging along the west coast will amplify and edge
eastward by Friday with warmer air temporarily advecting into the
cwa with highs into the 40s east and the low to mid 50s west. Models
are in agreement with the next strong northwest flow wave into the
eastern CONUS trough which will drive another push colder air back
into the cwa with highs mainly in the 30s Saturday...then the low to
mid 40s Sunday.
Even warmer air will then overspread the area on Monday with highs
mainly in the low to middle 50s as another longer wave trough
approaches the central plains. There will be a chance for rain
across the southeast cwa during the day...then a chance for rain or
snow that night as the cold front moves through.
&&
.AVIATION...(For the 00Z TAFs through 00Z Tuesday Evening)
Issued at 524 PM CST MON FEB 9 2015
...Update...
Adjusted TAFs as large clearing area has overtaken all TAF sites.
Still expect them to fill in with stratus later, with a best
estimate of around 09Z. There is some potential for dense fog to
develop over/near TAF sites during the early morning hours as
well, with the best chance at MHK, but confidence is not high at
this time so have not gone too low.
Just before 00Z, TOP/FOE had lost ceilings, although TOP was on
the edge of MVFR cigs. MHK was still under 1200 ft cigs, but a
clear slot was moving toward MHK and expect it to provide a
period of SCT clouds to MHK/TOP/FOE over the next few hours, but
with low confidence in timing of the cigs building back in. Even
if skies remain clear, would expect vis to drop to MVFR or IFR
category. All-told, this is a low confidence forecast for the
entire period, including how long ceilings will stay in place on
Tuesday as they may persist into the afternoon.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY until 9 AM CST Tuesday FOR KSZ008-020.
&&
$$
UPDATE...Barjenbruch
SHORT TERM...53
LONG TERM...63
AVIATION...Barjenbruch
AREA FORECAST DISCUSSION
NWS TOPEKA KS
529 PM CST Mon Feb 9 2015
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Tuesday)
Issued at 343 PM CST MON FEB 9 2015
Surface high pressure ridge extends southeast across eastern Kansas
from Minnesota. Cool east to northeast flow along with stratus which
has held on most of the day, has kept temperatures from rising much
from morning lows especially across north central Kansas.
Latest visible satellite loop shows the stratus breaking up from
central Missouri into east central Kansas. HRRR, NAM and RAP show
some semblance of this trend for partial clearing from Emporia to
Topeka along with some further clearing this evening into northeast
Kansas. Areas of north central Kansas look to stay in the stratus
tonight. The low clouds may reform later tonight across the east.
Areas of fog are likely for much of the area overnight. Lows tonight
will vary due to breaks in the clouds. Expecting lows in the upper
20s to low to mid 30s.
Thermal axis noses into northeast Kansas on Tuesday ahead of the
next shortwave and surface frontal boundary. Forecast soundings show
mixing to 925mb to 900mb in the afternoon. Stratus looks to break up
in the late morning and early afternoon hours. Highs will range from
the 50s to around 60.
.LONG TERM...(Tuesday Night through Monday)
Issued at 343 PM CST MON FEB 9 2015
Next cold front still on track to move through the county warning
area (cwa) Tuesday night as a weak shortwave trough extending from
the Great Lakes into the southwest CONUS moves through and shears
with time. The initial push of cooler air will lower highs into the
upper 30s and lower 40s for Wednesdays and should move through the
area dry as well.
As the stronger secondary d cold front moves through late
Wednesday/Wednesday night...a much colder push of air will
overspread the area. The GFS is deeper with the eastern trough and
colder than the EC. Following lows in the teens and lower 20s
Thursday morning...highs will struggle to reach the 20s and lower
30s most areas. Again...with only weak forcing and limited
moisture...will maintain a dry fcst.
The upper ridging along the west coast will amplify and edge
eastward by Friday with warmer air temporarily advecting into the
cwa with highs into the 40s east and the low to mid 50s west. Models
are in agreement with the next strong northwest flow wave into the
eastern CONUS trough which will drive another push colder air back
into the cwa with highs mainly in the 30s Saturday...then the low to
mid 40s Sunday.
Even warmer air will then overspread the area on Monday with highs
mainly in the low to middle 50s as another longer wave trough
approaches the central plains. There will be a chance for rain
across the southeast cwa during the day...then a chance for rain or
snow that night as the cold front moves through.
&&
.AVIATION...(For the 00Z TAFs through 00Z Tuesday Evening)
Issued at 524 PM CST MON FEB 9 2015
Just before 00Z, TOP/FOE had lost ceilings, although TOP was on
the edge of MVFR cigs. MHK was still under 1200 ft cigs, but a
clear slot was moving toward MHK and expect it to provide a
period of SCT clouds to MHK/TOP/FOE over the next few hours, but
with low confidence in timing of the cigs building back in. Even
if skies remain clear, would expect vis to drop to MVFR or IFR
category. All-told, this is a low confidence forecast for the
entire period, including how long ceilings will stay in place on
Tuesday as they may persist into the afternoon.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...53
LONG TERM...63
AVIATION...Barjenbruch
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1058 AM MST SUN FEB 8 2015
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 239 AM MST SUN FEB 8 2015
EARLY MORNING WV IMAGERY AND RAP H5 ANALYSIS SHOW WEST-NORTHWEST
FLOW IN PLACE ACROSS THE CENTRAL ROCKIES/PLAINS WITH A SHORTWAVE
TROUGH OVER EASTERN NEBRASKA. STRONG SUBSIDENCE/DRY LAYER REMAINS
IN PLACE OVER OUR CWA BEHIND THIS TROUGH. AT THE SURFACE WEAK
SURFACE LOW PRESSURE IS IN PLACE OVER OUR CWA...WITH BUILDING
HIGH PRESSURE FROM SOUTHEAST COLORADO.
PATTERN REMAINS WARM AND DRY THROUGH TUESDAY AS WESTERLY FLOW
PERSISTS TODAY...FOLLOWED BY SHORTWAVE RIDGING MONDAY. WHILE AIR
MASS WILL REMAIN WELL ABOVE NORMAL...WE PROBABLY WONT SEE RECORD
VALUES AS WAA WONT BE QUITE AS STRONG AS THE LAST FEW DAYS. WILL
STILL SEE HIGHS NEAR 70 TODAY AND MONDAY. UNIDIRECTIONAL NW
GRADIENT AND RISING HEIGHTS/SUBSIDENCE WILL SUPPORT BREEZY NW
WINDS (GUSTS 20-30 MPH) TODAY. LEE TROUGH DEVELOPING MONDAY WILL
ALLOW FOR INCREASING SOUTHERLY GRADIENT...AND WITH INCREASING
MIXING WOLD ANTICIPATE BREEZY SOUTH WINDS MONDAY (GUSTS 20-25
MPH).
TROUGH BEGINS TO SAG SOUTH INTO THE NORTHERN PLAINS TOWARDS THE
CWA TUESDAY AND OVER THE CWA TUESDAY NIGHT. FALLING HEIGHTS AND
WEAK CAA WILL RESULT IN HIGHS TUESDAY SLIGHTLY COOLER IN THE LOW-
MID 60S. POSITION AND TIMING OF THE H3 JET AHEAD OF THIS MID
LEVEL TROUGH WILL FAVOR MEASURABLE PRECIPITATION MAINLY OVER
EASTERN COLORADO TUESDAY NIGHT WHERE UPPER LEVEL DIVERGENCE IS
ADVERTISED BY GFS/ECMWF/NAM. WE COULD SEE SOME WEAK LIFT FURTHER
EAST IN OUR CWA...HOWEVER OVERALL MOISTURE PROFILES ARE
UNIMPRESSIVE. I KEPT SLIGHT CHANCE/CHANCE MENTION ALONG AND WEST
OF CO BORDER BASED ON BETTER PRECIP SIGNAL...AND INCLUDED MENTION
OF SPRINKLES/FLURRIES FURTHER EAST. COLD FRONT WILL BE SOUTH OF
THE REGION WITH INCREASING CAA AFTER MIDNIGHT. DESPITE THIS WE
WILL PROBABLY STILL ONLY SEE LOWS TUESDAY NIGHT DROP TO 30-35
RANGE DUE TO LIMITED RADIATIONAL COOLING. NOT ANTICIPATING MUCH
LIQUID PRECIP OR SNOW EVEN FOR LOCATIONS THAT SEE MEASURABLE.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 239 AM MST SUN FEB 8 2015
GOING INTO WEDNESDAY...MODELS CONTINUE TO SHOW SPLIT LEVEL FLOW OVER
THE REGION AS A SHORTWAVE/CUTOFF MOVES SOUTH THRU THE ROCKIES...AND
NORTHERN TROUGH SWINGS THRU THE NORTHERN PLAINS AND ON INTO THE
UPPER MISSISSIPPI VALLEY DURING THE DAY. MOISTURE DOES CONTINUE TO
BE VERY LIMITED AS THE FORMING CUTOFF SYSTEM TRAVERSES AREA. FOCUS
OF ANY PRECIP WILL BE CONFINED TO EASTERN COLORADO AS LIFT PROVIDED
BY LOW...COMBINED WITH EASTERLY FLOW OF SURFACE RIDGE BUILDING SOUTH
BEHIND TROUGH...GIVING EASTERN COLORADO ZONES SOME LIGHT
PRECIPITATION. LOOKING FOR MOSTLY LIGHT RAIN DUE TO DAYTIME
PASSAGE...BUT SLIGHTLY COLDER AIR DURING THE MORNING HOURS...COULD
AFFORD SOME LOCALES A BIT OF SNOW SHOWERS ACTIVITY MIXING WITH LIGHT
TRAIN AT TIMES.
DRY CONDITIONS WILL ENSUE AS SURFACE RIDGE SETS UP TO OUR EAST
THURSDAY ON INTO NEXT SATURDAY. A LEE-SIDE TROUGH MOVING OFF THE
FRONT RANGE DURING THIS TIME WILL AID IN WARM UP W/ DECENT SSW FLOW.
GOING INTO THE LATTER HALF OF NEXT WEEKEND...MODEL TREND REMAINS
HAVING BROAD H5 RIDGE TO WEST WITH STRONG UPPER LOW OVER THE EASTERN
PORTION OF THE COUNTRY. SOME MODEL DIFFERENCE FOR TIMING/PLACEMENT
OF WEAK SHORTWAVE THAT MOVES OFF THE ROCKIES ON SUNDAY. THIS SYSTEM
MOVES THRU AREA DURING THE SO PLAN ON KEEPING ANY PRECIP AT THIS
TIME NEAR SLIGHT CHANCE NUMBERS...WITH LIGHT RAIN BEING MAIN P-TYPE
DUE TO DAYTIME PASSAGE.
FOR TEMPS IN THE EXTENDED...DAYTIME HIGHS ARE EXPECTED TO BE NEAR 15
DEGREES ABOVE NORMAL...IN THE 50-60F RANGE WITH ONLY WEDNESDAY
LOOKING NEAR NORMAL IN THE 40S WITH SYSTEM PASSAGE AND CAA WITH
ARRIVAL OF CANADIAN RIDGE INTO AREA. OVERNIGHT LOWS WILL RANGE IN
THE 20S WHICH WILL STILL BE NEAR TO JUST ABOVE NORMAL BY 5-6
DEGREES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1052 AM MST SUN FEB 8 2015
CONDITIONS REMAIN VFR THROUGH THE TAF PERIOD AT MCK AND GLD. THE
UPPER RIDGE OVER THE WESTERN UNITED STATES MOVES OVER THE ROCKIES
AND HIGH PLANS REGION WHILE SURFACE HIGH PRESSURE MOVES EAST AND
IS REPLACED BY A DEEPENING LEE SURFACE TROUGH ON MONDAY. AS A
RESULT...GUSTY NORTHWEST WINDS TODAY SLACKEN AS THE SUN SETS AND
THEN TURNS SOUTHWEST AFTER 12Z MONDAY MORNING.
&&
.FIRE WEATHER...
ISSUED AT 239 AM MST SUN FEB 8 2015
WE COULD SEE MARGINAL/ELEVATED FIRE WEATHER CONDITIONS DEVELOP
TODAY...AND POSSIBLY MONDAY. WITH NW FLOW TODAY AND TD VALUES
TENDING TO HOLD UP WE SHOULD SEE RH VALUES REMAIN ABOVE 20
PERCENT FOR THE NORTHERN PARTS OF THE CWA...HOWEVER THERE ARE
STILL LOWER TD VALUES IN COLORADO THAT COULD ADVECT INTO OUR CWA
FROM THE WEST. INCREASED MIXING IN THE SOUTHWEST COULD ALSO RESULT
IN RH VALUES DROPPING TO THE UPPER TEENS ALONG AND SOUTH OF
INTERSTATE 70. RH VALUES WILL BE SLIGHTLY HIGHER MONDAY...BUT
STILL HOVERING AROUND 20 PERCENT. WITH BREEZY WINDS (GUSTS 20-30
MPH)...UNSEASONABLY WARM TEMPERATURES...AND DRY FUELS THE
SITUATION BEARS MONITORING. RED FLAG WARNING CRITERIA IS NOT
CURRENTLY FORECAST...BUT I WILL KEEP MENTION OF ELEVATED THREAT IN
HWO.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JN
AVIATION...LOCKHART
FIRE WEATHER...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
419 AM MST SUN FEB 8 2015
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 239 AM MST SUN FEB 8 2015
EARLY MORNING WV IMAGERY AND RAP H5 ANALYSIS SHOW WEST-NORTHWEST
FLOW IN PLACE ACROSS THE CENTRAL ROCKIES/PLAINS WITH A SHORTWAVE
TROUGH OVER EASTERN NEBRASKA. STRONG SUBSIDENCE/DRY LAYER REMAINS
IN PLACE OVER OUR CWA BEHIND THIS TROUGH. AT THE SURFACE WEAK
SURFACE LOW PRESSURE IS IN PLACE OVER OUR CWA...WITH BUILDING
HIGH PRESSURE FROM SOUTHEAST COLORADO.
PATTERN REMAINS WARM AND DRY THROUGH TUESDAY AS WESTERLY FLOW
PERSISTS TODAY...FOLLOWED BY SHORTWAVE RIDGING MONDAY. WHILE AIR
MASS WILL REMAIN WELL ABOVE NORMAL...WE PROBABLY WONT SEE RECORD
VALUES AS WAA WONT BE QUITE AS STRONG AS THE LAST FEW DAYS. WILL
STILL SEE HIGHS NEAR 70 TODAY AND MONDAY. UNIDIRECTIONAL NW
GRADIENT AND RISING HEIGHTS/SUBSIDENCE WILL SUPPORT BREEZY NW
WINDS (GUSTS 20-30 MPH) TODAY. LEE TROUGH DEVELOPING MONDAY WILL
ALLOW FOR INCREASING SOUTHERLY GRADIENT...AND WITH INCREASING
MIXING WOLD ANTICIPATE BREEZY SOUTH WINDS MONDAY (GUSTS 20-25
MPH).
TROUGH BEGINS TO SAG SOUTH INTO THE NORTHERN PLAINS TOWARDS THE
CWA TUESDAY AND OVER THE CWA TUESDAY NIGHT. FALLING HEIGHTS AND
WEAK CAA WILL RESULT IN HIGHS TUESDAY SLIGHTLY COOLER IN THE LOW-
MID 60S. POSITION AND TIMING OF THE H3 JET AHEAD OF THIS MID
LEVEL TROUGH WILL FAVOR MEASURABLE PRECIPITATION MAINLY OVER
EASTERN COLORADO TUESDAY NIGHT WHERE UPPER LEVEL DIVERGENCE IS
ADVERTISED BY GFS/ECMWF/NAM. WE COULD SEE SOME WEAK LIFT FURTHER
EAST IN OUR CWA...HOWEVER OVERALL MOISTURE PROFILES ARE
UNIMPRESSIVE. I KEPT SLIGHT CHANCE/CHANCE MENTION ALONG AND WEST
OF CO BORDER BASED ON BETTER PRECIP SIGNAL...AND INCLUDED MENTION
OF SPRINKLES/FLURRIES FURTHER EAST. COLD FRONT WILL BE SOUTH OF
THE REGION WITH INCREASING CAA AFTER MIDNIGHT. DESPITE THIS WE
WILL PROBABLY STILL ONLY SEE LOWS TUESDAY NIGHT DROP TO 30-35
RANGE DUE TO LIMITED RADIATIONAL COOLING. NOT ANTICIPATING MUCH
LIQUID PRECIP OR SNOW EVEN FOR LOCATIONS THAT SEE MEASURABLE.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 239 AM MST SUN FEB 8 2015
GOING INTO WEDNESDAY...MODELS CONTINUE TO SHOW SPLIT LEVEL FLOW OVER
THE REGION AS A SHORTWAVE/CUTOFF MOVES SOUTH THRU THE ROCKIES...AND
NORTHERN TROUGH SWINGS THRU THE NORTHERN PLAINS AND ON INTO THE
UPPER MISSISSIPPI VALLEY DURING THE DAY. MOISTURE DOES CONTINUE TO
BE VERY LIMITED AS THE FORMING CUTOFF SYSTEM TRAVERSES AREA. FOCUS
OF ANY PRECIP WILL BE CONFINED TO EASTERN COLORADO AS LIFT PROVIDED
BY LOW...COMBINED WITH EASTERLY FLOW OF SURFACE RIDGE BUILDING SOUTH
BEHIND TROUGH...GIVING EASTERN COLORADO ZONES SOME LIGHT
PRECIPITATION. LOOKING FOR MOSTLY LIGHT RAIN DUE TO DAYTIME
PASSAGE...BUT SLIGHTLY COLDER AIR DURING THE MORNING HOURS...COULD
AFFORD SOME LOCALES A BIT OF SNOW SHOWERS ACTIVITY MIXING WITH LIGHT
TRAIN AT TIMES.
DRY CONDITIONS WILL ENSUE AS SURFACE RIDGE SETS UP TO OUR EAST
THURSDAY ON INTO NEXT SATURDAY. A LEE-SIDE TROUGH MOVING OFF THE
FRONT RANGE DURING THIS TIME WILL AID IN WARM UP W/ DECENT SSW FLOW.
GOING INTO THE LATTER HALF OF NEXT WEEKEND...MODEL TREND REMAINS
HAVING BROAD H5 RIDGE TO WEST WITH STRONG UPPER LOW OVER THE EASTERN
PORTION OF THE COUNTRY. SOME MODEL DIFFERENCE FOR TIMING/PLACEMENT
OF WEAK SHORTWAVE THAT MOVES OFF THE ROCKIES ON SUNDAY. THIS SYSTEM
MOVES THRU AREA DURING THE SO PLAN ON KEEPING ANY PRECIP AT THIS
TIME NEAR SLIGHT CHANCE NUMBERS...WITH LIGHT RAIN BEING MAIN P-TYPE
DUE TO DAYTIME PASSAGE.
FOR TEMPS IN THE EXTENDED...DAYTIME HIGHS ARE EXPECTED TO BE NEAR 15
DEGREES ABOVE NORMAL...IN THE 50-60F RANGE WITH ONLY WEDNESDAY
LOOKING NEAR NORMAL IN THE 40S WITH SYSTEM PASSAGE AND CAA WITH
ARRIVAL OF CANADIAN RIDGE INTO AREA. OVERNIGHT LOWS WILL RANGE IN
THE 20S WHICH WILL STILL BE NEAR TO JUST ABOVE NORMAL BY 5-6
DEGREES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 419 AM MST SUN FEB 8 2015
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD. WESTERLY WINDS
WILL BECOME NORTHWEST AND INCREASE WITH UNIDIRECTIONAL GRADIENT
DEVELOPING BY MIDDAY AT BOTH KGLD AND KMCK. GUSTS WILL RANGE FROM
25-30KT WITH STRONGEST WINDS AT KGLD. WINDS WILL DIMINISH TO LESS
THAN 12KT AROUND SUNSET...EVENTUALLY SHIFTING BACK TO THE
SOUTHWEST AS SURFACE LOW PRESSURE REDEVELOPS IN EASTERN COLORADO.
&&
.FIRE WEATHER...
ISSUED AT 239 AM MST SUN FEB 8 2015
WE COULD SEE MARGINAL/ELEVATED FIRE WEATHER CONDITIONS DEVELOP
TODAY...AND POSSIBLY MONDAY. WITH NW FLOW TODAY AND TD VALUES
TENDING TO HOLD UP WE SHOULD SEE RH VALUES REMAIN ABOVE 20
PERCENT FOR THE NORTHERN PARTS OF THE CWA...HOWEVER THERE ARE
STILL LOWER TD VALUES IN COLORADO THAT COULD ADVECT INTO OUR CWA
FROM THE WEST. INCREASED MIXING IN THE SOUTHWEST COULD ALSO RESULT
IN RH VALUES DROPPING TO THE UPPER TEENS ALONG AND SOUTH OF
INTERSTATE 70. RH VALUES WILL BE SLIGHTLY HIGHER MONDAY...BUT
STILL HOVERING AROUND 20 PERCENT. WITH BREEZY WINDS (GUSTS 20-30
MPH)...UNSEASONABLY WARM TEMPERATURES...AND DRY FUELS THE
SITUATION BEARS MONITORING. RED FLAG WARNING CRITERIA IS NOT
CURRENTLY FORECAST...BUT I WILL KEEP MENTION OF ELEVATED THREAT IN
HWO.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JN
AVIATION...DR
FIRE WEATHER...DR
AREA FORECAST DISCUSSION...CORRECTED
NWS GOODLAND KS
239 AM MST SUN FEB 8 2015
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 239 AM MST SUN FEB 8 2015
EARLY MORNING WV IMAGERY AND RAP H5 ANALYSIS SHOW WEST-NORTHWEST
FLOW IN PLACE ACROSS THE CENTRAL ROCKIES/PLAINS WITH A SHORTWAVE
TROUGH OVER EASTERN NEBRASKA. STRONG SUBSIDENCE/DRY LAYER REMAINS
IN PLACE OVER OUR CWA BEHIND THIS TROUGH. AT THE SURFACE WEAK
SURFACE LOW PRESSURE IS IN PLACE OVER OUR CWA...WITH BUILDING
HIGH PRESSURE FROM SOUTHEAST COLORADO.
PATTERN REMAINS WARM AND DRY THROUGH TUESDAY AS WESTERLY FLOW
PERSISTS TODAY...FOLLOWED BY SHORTWAVE RIDGING MONDAY. WHILE AIR
MASS WILL REMAIN WELL ABOVE NORMAL...WE PROBABLY WONT SEE RECORD
VALUES AS WAA WONT BE QUITE AS STRONG AS THE LAST FEW DAYS. WILL
STILL SEE HIGHS NEAR 70 TODAY AND MONDAY. UNIDIRECTIONAL NW
GRADIENT AND RISING HEIGHTS/SUBSIDENCE WILL SUPPORT BREEZY NW
WINDS (GUSTS 20-30 MPH) TODAY. LEE TROUGH DEVELOPING MONDAY WILL
ALLOW FOR INCREASING SOUTHERLY GRADIENT...AND WITH INCREASING
MIXING WOLD ANTICIPATE BREEZY SOUTH WINDS MONDAY (GUSTS 20-25
MPH).
TROUGH BEGINS TO SAG SOUTH INTO THE NORTHERN PLAINS TOWARDS THE
CWA TUESDAY AND OVER THE CWA TUESDAY NIGHT. FALLING HEIGHTS AND
WEAK CAA WILL RESULT IN HIGHS TUESDAY SLIGHTLY COOLER IN THE LOW-
MID 60S. POSITION AND TIMING OF THE H3 JET AHEAD OF THIS MID
LEVEL TROUGH WILL FAVOR MEASURABLE PRECIPITATION MAINLY OVER
EASTERN COLORADO TUESDAY NIGHT WHERE UPPER LEVEL DIVERGENCE IS
ADVERTISED BY GFS/ECMWF/NAM. WE COULD SEE SOME WEAK LIFT FURTHER
EAST IN OUR CWA...HOWEVER OVERALL MOISTURE PROFILES ARE
UNIMPRESSIVE. I KEPT SLIGHT CHANCE/CHANCE MENTION ALONG AND WEST
OF CO BORDER BASED ON BETTER PRECIP SIGNAL...AND INCLUDED MENTION
OF SPRINKLES/FLURRIES FURTHER EAST. COLD FRONT WILL BE SOUTH OF
THE REGION WITH INCREASING CAA AFTER MIDNIGHT. DESPITE THIS WE
WILL PROBABLY STILL ONLY SEE LOWS TUESDAY NIGHT DROP TO 30-35
RANGE DUE TO LIMITED RADIATIONAL COOLING. NOT ANTICIPATING MUCH
LIQUID PRECIP OR SNOW EVEN FOR LOCATIONS THAT SEE MEASURABLE.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 239 AM MST SUN FEB 8 2015
GOING INTO WEDNESDAY...MODELS CONTINUE TO SHOW SPLIT LEVEL FLOW OVER
THE REGION AS A SHORTWAVE/CUTOFF MOVES SOUTH THRU THE ROCKIES...AND
NORTHERN TROUGH SWINGS THRU THE NORTHERN PLAINS AND ON INTO THE
UPPER MISSISSIPPI VALLEY DURING THE DAY. MOISTURE DOES CONTINUE TO
BE VERY LIMITED AS THE FORMING CUTOFF SYSTEM TRAVERSES AREA. FOCUS
OF ANY PRECIP WILL BE CONFINED TO EASTERN COLORADO AS LIFT PROVIDED
BY LOW...COMBINED WITH EASTERLY FLOW OF SURFACE RIDGE BUILDING SOUTH
BEHIND TROUGH...GIVING EASTERN COLORADO ZONES SOME LIGHT
PRECIPITATION. LOOKING FOR MOSTLY LIGHT RAIN DUE TO DAYTIME
PASSAGE...BUT SLIGHTLY COLDER AIR DURING THE MORNING HOURS...COULD
AFFORD SOME LOCALES A BIT OF SNOW SHOWERS ACTIVITY MIXING WITH LIGHT
TRAIN AT TIMES.
DRY CONDITIONS WILL ENSUE AS SURFACE RIDGE SETS UP TO OUR EAST
THURSDAY ON INTO NEXT SATURDAY. A LEE-SIDE TROUGH MOVING OFF THE
FRONT RANGE DURING THIS TIME WILL AID IN WARM UP W/ DECENT SSW FLOW.
GOING INTO THE LATTER HALF OF NEXT WEEKEND...MODEL TREND REMAINS
HAVING BROAD H5 RIDGE TO WEST WITH STRONG UPPER LOW OVER THE EASTERN
PORTION OF THE COUNTRY. SOME MODEL DIFFERENCE FOR TIMING/PLACEMENT
OF WEAK SHORTWAVE THAT MOVES OFF THE ROCKIES ON SUNDAY. THIS SYSTEM
MOVES THRU AREA DURING THE SO PLAN ON KEEPING ANY PRECIP AT THIS
TIME NEAR SLIGHT CHANCE NUMBERS...WITH LIGHT RAIN BEING MAIN P-TYPE
DUE TO DAYTIME PASSAGE.
FOR TEMPS IN THE EXTENDED...DAYTIME HIGHS ARE EXPECTED TO BE NEAR 15
DEGREES ABOVE NORMAL...IN THE 50-60F RANGE WITH ONLY WEDNESDAY
LOOKING NEAR NORMAL IN THE 40S WITH SYSTEM PASSAGE AND CAA WITH
ARRIVAL OF CANADIAN RIDGE INTO AREA. OVERNIGHT LOWS WILL RANGE IN
THE 20S WHICH WILL STILL BE NEAR TO JUST ABOVE NORMAL BY 5-6
DEGREES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1038 PM MST SAT FEB 7 2015
LITTLE CHANGE IN THINKING FROM THE PREVIOUS TAF ISSUANCE. VFR
CONDITIONS ARE EXPECTED THROUGH THE PERIOD. A COLD FRONT WILL BE
MOVING THROUGH THE AREA. THIS WILL INCREASE THE WINDS SOME IN THE
FIRST 6 HOURS. THE BIGGER INCREASE IN THE WINDS WILL BE AFTER THE
SUN COMES UP. THESE GUSTY WINDS WILL LAST UNTIL LATE IN THE
AFTERNOON.
&&
.FIRE WEATHER...
ISSUED AT 239 AM MST SUN FEB 8 2015
WE COULD SEE MARGINAL/ELEVATED FIRE WEATHER CONDITIONS DEVELOP
TODAY...AND POSSIBLY MONDAY. WITH NW FLOW TODAY AND TD VALUES
TENDING TO HOLD UP WE SHOULD SEE RH VALUES REMAIN ABOVE 20
PERCENT FOR THE NORTHERN PARTS OF THE CWA...HOWEVER THERE ARE
STILL LOWER TD VALUES IN COLORADO THAT COULD ADVECT INTO OUR CWA
FROM THE WEST. INCREASED MIXING IN THE SOUTHWEST COULD ALSO RESULT
IN RH VALUES DROPPING TO THE UPPER TEENS ALONG AND SOUTH OF
INTERSTATE 70. RH VALUES WILL BE SLIGHTLY HIGHER MONDAY...BUT
STILL HOVERING AROUND 20 PERCENT. WITH BREEZY WINDS (GUSTS 20-30
MPH)...UNSEASONABLY WARM TEMPERATURES...AND DRY FUELS THE
SITUATION BEARS MONITORING. RED FLAG WARNING CRITERIA IS NOT
CURRENTLY FORECAST...BUT I WILL KEEP MENTION OF ELEVATED THREAT IN
HWO.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JN
AVIATION...BULLER
FIRE WEATHER...DR
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
448 PM CST SUN FEB 8 2015
.AVIATION...
COLD FRONT WAS NEAR A HRO...GYI...SEP...JCT LINE AS OF 22Z THIS
AFTN. FRONT SHOULD REALLY PICK UP SPEED THIS EVENING AND SHOULD
PUSH THROUGH ALL OUR TERMINAL LOCATIONS BEFORE 06Z TNGT. AHEAD OF
THE FRONT...EXTENSIVE CU FIELD EXISTS WITH HEIGHTS RANGING FROM
4-6KFT. THIS CU FIELD IS AFFECTING ALL TERMINALS...ALBEIT A LITTLE
THIN IN AND AROUND THE TYR/GGG AND MLU TERMINALS WHERE MIXING HAS
HELPED TO CREATE A FEW BREAKS IN THE OVC. THE BACK EDGE OF THIS
CLOUD COVER WAS ADVANCING SOUTHEAST NEAR 18-20KTS AND THUS...THE
TXK AND TYR TERMINALS WILL HAVE LIKELY LOST THEIR LOWER CEILINGS
WITH THE 00Z TAF PACKAGE.
LATEST RUN OF THE HRRR SUGGESTS SOME ISOLATED TO WIDELY SCATTERED
SHOWERS DEVELOPING MAINLY SOUTH OF THE I-20 CORRIDOR...POSSIBLY
EFFECTING THE LFK/MLU TERMINALS. THIS SEEMS POSSIBLE AS FRONTAL
FORCING WILL BE A LITTLE STRONGER IN THE VICINITY OF THESE TWO
TERMINALS. MENTIONED VCSH FOR A FEW HOURS THIS EVENING FOR THESE
LOCATIONS UNTIL THE FRONT BYPASSES THEM AFTER MIDNIGHT.
OTHERWISE...VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD.
EXPECTING A WEAK WIND SHIFT WITH THE FRONTAL PASSAGE THIS EVENING
WITH WINDS BECOMING NW. A MORE NORTHERLY DIRECTION IS EXPECTED BY
MID TO LATE MORNING ON MONDAY WITH SPEEDS PICKING UP TO AROUND
8-10KTS WITH SUFFICIENT MIXING.
13
&&
.PREV DISCUSSION... /ISSUED 349 PM CST SUN FEB 8 2015/
DISCUSSION...
GENERALLY QUIET WEATHER IS EXPECTED OVER THE NEXT SEVERAL DAYS
WITH ABOVE NORMAL TEMPERATURES EXPECTED THROUGH THURSDAY AND VERY
LITTLE OF THE WAY OF RAIN CHANCES.
PERSISTENT STRATUS DECK HAS BEEN SCATTERING OUT SOUTH OF I-20
TODAY BUT A THICK BAND OF CLOUD COVER WILL MOVE ACROSS THE AREA
AHEAD OF A SFC TROUGH. THE TROUGH WILL MOVE ACROSS THE AREA THIS
EVENING/TONIGHT AND SKIES SHOULD RAPIDLY CLEAR AFTER IT PASSES AS
WINDS SHIFT TO THE NORTH AND DRIER AIR WORKS INTO THE REGION. MID
LVL SHORTWAVE TROUGH CURRENTLY OVER NRN KS WILL DIVE SEWD AND
COULD PROVIDE SOME ADDITIONAL ASCENT ALONG THE SFC BOUNDARY TO
DEVELOP A FEW SHWRS SOUTH OF I-20 TONIGHT. I CONSIDERED REMOVING
POPS COMPLETELY TONIGHT AS IT APPEARS FROM THE LATEST WV LOOPS
THAT THE SHORTWAVE MAY TRACK A LITTLE FARTHER NORTH AND AWAY FROM
THE SFC BOUNDARY THAN THE MODEL GUIDANCE SUGGESTS. HOWEVER...CANNOT
COMPLETELY RULE OUT A COUPLE OF SHWRS SO WILL MAINTAIN THE SLIGHT
CHANCE POPS.
UPPER RIDGING AND A SFC HIGH PRESSURE SHOULD DOMINATE OUR WEATHER
FOR MONDAY AND TUESDAY. VAST MAJORITY OF THE MODELS WERE WAY TOO
COOL WITH THEIR MAX TEMP FORECASTS FOR TODAY. LOOKING UPSTREAM
BEHIND THE TROUGH IN OK...TEMPS HAVE BEEN WARMER THAN OURS WITH
SOME LOCATIONS NEAR OR ABOVE 80 DEGREES F. GIVEN THE CONDITIONS
UPSTREAM AND WITH MOSTLY CLEAR SKIES...PLENTY OF DRY AIR...AND
UPPER RIDGING EXPECTED OVERHEAD...MAX TEMPS ON MONDAY SHOULD BE
NEAR IF NOT WARMER THAN TODAY SO HAVE GONE WARMER THAN MOST OF THE
MODELS. TEMPS MAY BE A BIT COOLER ON TUESDAY AS THE LOW LVL FLOW
BECOMES ELY WHICH COULD ADVECT SOME SLIGHTLY COOLER AIR INTO THE
REGION. TEMPS SHOULD REBOUND BACK TO NEAR OR ABOVE 70 DEGREES F ON
WEDNESDAY AHEAD OF OUR NEXT COLD FRONT.
COLD FRONT SHOULD ARRIVE LATE WEDNESDAY/EARLY FRIDAY. LATEST
MODELS GENERALLY MAINTAIN A DRY FORECAST AND THIS MAKES SENSE AS
THERE WILL BE LITTLE TIME FOR DEEP LAYER MOISTURE TO BUILD PRIOR
TO THE FRONT/S ARRIVAL. COLDER AIR WILL ARRIVE BEHIND THE FRONT
WHICH SHOULD COOL TEMPS BACK TO NEAR CLIMO FOR THE END OF THE WORK
WEEK FOLLOWED BY ANOTHER WARMING TREND HEADING INTO NEXT WEEKEND.
/09/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 49 71 40 65 42 / 10 0 0 0 0
MLU 51 69 37 60 37 / 20 0 0 0 0
DEQ 39 69 37 63 40 / 0 0 0 0 0
TXK 47 68 39 63 40 / 10 0 0 0 0
ELD 47 66 36 60 38 / 10 0 0 0 0
TYR 48 72 42 70 45 / 10 0 0 0 0
GGG 47 72 42 68 44 / 10 0 0 0 0
LFK 53 74 43 71 45 / 20 0 0 0 0
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
09/13
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
650 PM EST MON FEB 9 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 348 PM EST MON FEB 9 2015
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A NW FLOW ALOFT
OVER THE GREAT LKS BTWN AN UPR RDG OVER THE WRN PLAINS AND A TROF
ACROSS THE ERN CONUS. A SHRTWV EMBEDDED IN THIS NW FLOW AND
ACCOMPANYING AREA OF SOMEWHAT DEEPER MSTR/DYNAMIC FORCING THAT
LIFTED INVRN BASE UP TO ARND 4K FT AGL BROUGHT AN UPTICK THIS MRNG
TO THE LES IN THE PRESENCE OF INVRN BASE TEMPS ARND -12C OVER MAINLY
THE NCNTRL WHERE OBSVD N WINDS UPSLOPE. BUT DNVA/SUBSIDENCE IN THE
WAKE OF THE SHRTWV PASSAGE AND IN ADVANCE OF APRCHG SHRTWV RDG HAVE
CAUSED THE LES TO DIMINISH THIS AFTN...AND EVEN FOR THE LO CLDS TO
BREAK UP TO A CERTAIN EXTENT. SINCE THE 12Z INL/YPL ROABS TO THE NW
SHOW MSTR EXTENDING UP THRU ABOUT H7...PLENTY OF CLD COVER AND SOME
FLURRIES LINGER UPSTREAM IN NRN MN AND NW ONTARIO. LOOKING FARTHER
UPSTREAM...A FAIRLY VIGOROUS SHRTWV IS MOVING INTO THE PAC NW AND
OVER THE WRN RDG.
LATE TODAY/TNGT...ALTHOUGH THE LLVLS WL REMAIN COLD ENUF FOR LES...
LARGE SCALE SUBSIDENCE IN ADVANCE OF APRCHG SHRTWV RDG THAT DEPRESS
INVRN BASE TOWARD 2-3K FT WL LIMIT LES INTENSITY AND COVERAGE.
INITIALLY...LLVL LIGHT WINDS ARE FCST TO BACK TOWARD THE NW INTO
THIS EVNG AHEAD OF THE INCOMING SFC RDG. SO MOST OF THE LINGERING
LES/LK CLDS SHOULD BE TO THE E OF MQT AND OVER THE KEWEENAW THIS
EVNG. LIGHT WINDS ASSOCIATED WITH THE PASSING SFC RDG AXIS MAY ALLOW
FOR A MESOLO PRES TO DVLP. HOWEVER...PRESENCE OF A GOOD DEAL OF ICE
NEAR LK SUP E OF MARQUETTE WL LIMIT THE POTENTIAL IMPACT OF THIS
FEATURE IN THESE AREAS. AS THE WINDS TEND TO SHIFT BACK TO THE NE
LATER FOLLOWING THE PASSAGE OF THE RDG AXIS TO THE E...SOME LES
MIGHT SHIFT BACK TOWARD MARQUETTE. ANOTHER WEAK SHRTWV/AREA OF DEEP
LYR QVECTOR CNVGC IS FCST TO MOVE BY LATE TNGT. BUT SINCE SFC RDG
AXIS WL BE PASSING THRU AT THAT TIME...THE IMPACT SHOULD BE MINIMAL.
EXPECT THE LOWEST MIN TEMPS OVER THE E AND SCNTRL WHERE LIGHT E
WINDS WL DRAIN OFF SOME VERY COLD OVER ONTARIO AND MSTR/CLDS TO THE
NW WL HAVE A HARDER TIME REACHING.
TUE...LARGE SCALE WAA/DEEP LYR QVECTOR CNVGC/UPR DVGC IN INCRSG SSE
FLOW BTWN DEPARTING SFC HI PRES RDG TO THE E AND IN ADVANCE OF
SHRTWV NOW OVER THE PAC NW THAT WL BE MOVING THRU THE NRN PLAINS IS
FCST TO ARRIVE IN THE AFTN. THE ARRIVAL OF THIS FORCING AND
ACCOMPANYING UVV WL ALLOW FOR THICKENING CLDS AND SOME SN TO PUSH
INTO THE WRN COUNTIES DURING THE AFTN. H7 SPECIFIC HUMIDITY FCST UP
TO 3 G/KG UNDER THE AXIS OF WAA INDICATES A FEW INCHES OF SN MAY
ACCUMULATE OVER THE FAR W BY 00Z DESPITE A RATHER HI...NARROW DGZ.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 510 PM EST MON FEB 9 2015
BOUTS OF COLD AND SNOW WILL BE THE THEME FOR THE LONG TERM PERIOD.
SNOW WILL BE EXPANDING W TO E ACROSS THE CWA TUESDAY NIGHT AS THE
MAIN SFC LOW OVER S AND CENTRAL MN CROSSES FAR W BY 06Z...AND SPLITS
THE AREA IN HALF BY 12Z WEDNESDAY. 850MB TEMPS WILL FALL TO AROUND -
12C BEHIND THE LOW...WITH -20C AIR WEDNESDAY EVENING ON FAVORABLE
UPSLOPE FLOW.
CONTINUED TO MENTION THE POTENTIAL FOR WIDESPREAD SNOW TUESDAY
AFTERNOON THROUGH TUESDAY NIGHT WITH A FEW INCHES OF SNOW
ACCUMULATION POSSIBLE...THEN LAKE EFFECT SNOW WEDNESDAY INTO
THURSDAY. GUSTY NW TO N WINDS WILL HELP PRODUCE BLOWING SNOW AND
REDUCED VIS WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING. MAY NEED
TO ISSUE WINTER WX ADVISORY FOR THE 2-4.5IN OF SNOW TUESDAY THROUGH
DAYBREAK WEDNESDAY...AND DEPENDING ON THE FOCUS OF MODERATE LES FOR
SNOW AND BLOWING SNOW FOR THE LONGER DURATION LES FOR THE N WIND
FAVORED AREAS OF GOGEBIC/ONTONAGON AND BARAGA/MARQUETTE E ALONG LAKE
SUPERIOR AS 850MB TEMPS FALL TO AROUND -25C.
WITH ALL THIS COLD AIR...WIND CHILL VALUES ARE EXPECTED TO FALL
BETWEEN 15 BELOW AND 25 BELOW ZERO THURSDAY MORNING INLAND FROM THE
GREAT LAKES.
THE N WINDS WILL ALSO BE A CONCERN FOR LATE FRIDAY EVENING THROUGH
ALL OF SATURDAY...WITH THE BEST CHANCE OF LES N CENTRAL. DID BUMP UP
THE WINDS/GUSTS APPROX 5KTS SATURDAY MORNING. LOOKING AT IT FROM A
DIFFERENT PERSPECTIVE...THIS WIND SATURDAY WILL PROBABLY RESULT IN A
RESTRICTION OR ROAD CLOSURE OF M-28 EAST OF HARVEY THROUGH MUNISING
LATE FRIDAY NIGHT THROUGH SATURDAY MORNING...ESPECIALLY CONSIDERING
THE AMOUNT OF SNOW THAT WILL BE ABLE TO ACCUMULATE ON THE SNOW JUST
OFFSHORE. AS THIS IS STILL 4-5 DAYS OUT...LOOK FOR ADJUSTMENTS TO
THE ONGOING FCST. IMPROVING CONDITIONS WILL COME IN SATURDAY NIGHT
AS THE SFC LOW SINING ACROSS THE UPPER GREAT LAKES FRIDAY
AFTERNOON/EVENING PUSHES TO THE CENTRAL APPALACHIANS BY SATURDAY
AFTERNOON. VERY STRONG HIGH PRESSURE ACROSS S CANADA AND THE CENTRAL
PLAINS WILL THEN SLOWLY MOVE IN. THE SFC RIDGE WILL BE
DIRECTLY OVERHEAD SUNDAY MORNING.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 647 PM EST MON FEB 9 2015
VFR CONDITIONS WILL LIKELY PREVAIL AT KIWD THRU MID AFTN TUE AS
LIGHT/CALM WIND BECOMES A DOWNSLOPE SE WIND. AT KCMX...VFR
CONDITIONS SHOULD CONTINUE THRU THE EVENING BEFORE MVFR CIGS ARRIVE
OVERNIGHT AS WINDS BECOME EASTERLY ACROSS THE OPEN WATERS OF LAKE
SUPERIOR. AT KSAW...VFR CONDITIONS SHOULD CONTINUE THIS EVENING
BEFORE LIGHT NE WINDS BRING A RETURN OF MVFR CIGS OFF LAKE SUPERIOR
OVERNIGHT. CONTINUED UPSLOPE FLOW AS WINDS VEER SE MAY BRING A
PERIOD OF IFR CIGS TO KSAW IN THE MORNING. LATE IN THE AFTN...
DISTURBANCE APPROACHING FROM THE W WILL BRING -SN/IFR CONDITIONS TO
KIWD/KCMX.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 PM EST MON FEB 9 2015
A COUPLE ROUNDS AND HEAVY FREEZING SPRAY ARE EXPECTED THIS PERIOD. A
RIDGE ACROSS LAKE SUPERIOR WILL SLOWLY ERODE TUESDAY...AS A LOW
NEARS FROM THE N PLAINS. EXPECT THE LOW TO CROSS THE UPPER GREAT
LAKE TUESDAY NIGHT AND WEDNESDAY...THE LOWER GREAT LAKES WEDNESDAY
NIGHT...AND EVENTUALLY END UP DEEPENING SIGNIFICANTLY OFF THE NEW
ENGLAND COAST THURSDAY NIGHT. THIS WILL BE WHILE A HIGH ACROSS S
CENTRAL CANADA WEDNESDAY MOVES TO THE MID MS VALLEY THURSDAY NIGHT
...AND BUILDS A RIDGE ACROSS LAKE SUPERIOR LATE THURSDAY INTO
THURSDAY NIGHT. A GALE WATCH HAS BEEN ISSUED FOR MUCH OF CENTRAL TO
E LAKE SUPERIOR WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING AS
MAINLY N WINDS INCREASE W/30-40KT GUSTS.
LOOK FOR A LOW ACROSS MANITOBA THURSDAY NIGHT TO SINK ACROSS THE
UPPER GREAT LAKES FRIDAY...AND INTO THE CENTRAL APPALACHIANS
SATURDAY AFTERNOON...WHILE LARGE HIGH PRESSURE NEARS FROM THE S
CENTRAL CANADA AND THE NORTHERN PLAINS. THIS WILL BRING ABOUT
ANOTHER PERIOD OF MAINLY N GALES OF 35-40KTS OVER MUCH OF LAKE
SUPERIOR FRIDAY EVENING THROUGH SATURDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY AFTERNOON
FOR LSZ266-267.
GALE WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING FOR
LSZ265.
GALE WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING FOR
LSZ264.
GALE WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING FOR
LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...ROLFSON
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1256 PM EST SUN FEB 8 2015
.UPDATE...
ISSUED AT 1007 AM EST SUN FEB 8 2015
FCST MODEL SNOW RATIOS FOR THE BAND OF FLUFFY SNOW ARE WAY
OFF...MORE LIKE 25:1 AND NOT THE 15:1 SHOWN OFF THE NAM/BUFKIT. AS A
RESULT...WE HAVE SEEN 1 IN/HR ACCUMULATIONS ALREADY OVER THE DEAD
RIVER BASIN. WENT AHEAD AND INCREASED NOT ONLY RATIOS...BUT
QPF...AND SNOW AMOUNTS. GOING WITH AROUND 2IN OVER THE HIGHER ACROSS
THE KEWEENAW PENINSULA AND MARQUETTE COUNTY FROM THE HURON MOUNTAINS
THROUGH NEGAUNEE/ISHPEMING. WHILE MOISTURE DOES SLOWLY DECREASE AND
INVERSION HEIGHTS WILL BE LOWERING EVEN MORE /BELOW 4KFT...THIS AREA
IS IN THE DGZ. CONTINUED LIGHT LES WILL BE THE RULE. UPDATES WERE
MADE TO THE ONGOING FCST FOR THIS BETWEEN 830 AND 930AM.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 418 AM EST SUN FEB 8 2015
IT APPEARS THAT MUCH OF THE FREEZING DRIZZLE FROM LAST EVENING/EARLY
OVERNIGHT HAS TURNED OVER TO LIGHT -SHSN OR FLURRIES ACROSS MUCH OF
THE CWA AS TEMPS HAVE COOLED BLO -10C IN THE LOWEST 2KFT OF THE
AIRMASS PER RAP SOUNDINGS. IF THERE IS ANY REMAINING -FZDZ OVER SE
SECTIONS IT SHOULD BE GONE BY SUNRISE WITH THE COOLER TEMPS ALLOWING
FOR ICE CRYSTAL FORMATION IN THE CONVECTIVE LAYER.
NE FLOW AND TEMPS TO NEAR -15C WITHIN THE LOWEST 3KFT OF ATMOSPHERE
WILL FAVOR 4 WRN COUNTIES AND WRN MQT-BARAGA COUNTIES FOR LIGHT LES
TODAY. LIMITING FACTOR BESIDES FAIRLY MARGINAL INSTABILITY WILL BE
INVERSION WITHIN LOWEST 3KFT SO NOT EXPECTING MUCH IN THE WAY OF
ACCUMULATION WITH A DUSTING TO MAYBE AN INCH FOR AREAS BEST AIDED BY
UPSLOPE NE FLOW. MAX TEMPS TODAY WILL GENERALLY RANGE FROM THE TEENS
NORTH TO LOWER 20S ALONG THE WI BORDER.
WITH SHORTWAVE RIDGE AND SFC RIDGE MOVING OVERHEAD...EXPECT
SIGNIFICANT DRYING/SUBSIDENCE ALOFT TONIGHT. NAM SNDGS SHOW MOISTURE
SHALLOWING OUT BLO LOWEST 2KFT FM SFC...BUT WITH TEMP AT INVERSION
BASE OF -13 TO -14C...THERE WILL LIKELY BE SOME LIGHT LES/FLURRIES
OFF THE LAKE...ESPECIALLY FOR UPSLOPE NE TO N FLOW AREAS. STILL
WOULDN/T EXPECT ACCUMULATION ANY MORE THAN HALF AN INCH. WITH LIGHT
ERLY FLOW SETTING UP OVER FAR ERN COUNTIES THERE COULD BE SOME
CLEARING TO ALLOW TEMPS TO FALL FM 5 TO 10 BELOW ZERO AT SOME OF
TYPICAL COLD SPOTS. OVER THE WEST HALF AND SOUTH CENTRAL...TEMPS
WILL RANGE FROM THE SINGLE DIGITS ABV ZERO INLAND TO 10F OR HIGHER
NEAR THE GREAT LAKES SHORELINES.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 401 AM EST SUN FEB 8 2015
MUCH OF THE FOCUS DURING THE LONG TERM FORECAST WILL BE WITH THE
LOW PRESSURE SYSTEM MOVING EAST THROUGH THE GREAT LAKES REGION
TUESDAY NIGHT AND THEN THE COLD AIR SURGING SOUTH INTO THE AREA AND
LEADING TO ANOTHER PERIOD OF MODERATE LAKE EFFECT SNOW WEDNESDAY
AFTERNOON INTO THURSDAY MORNING.
BEFORE THE ACTIVE WEATHER DURING THE MIDDLE OF THE WEEK...THE AREA
WILL BE UNDER A WEAK SURFACE RIDGE THAT WILL BE MOVING ACROSS THE
UPPER GREAT LAKES MONDAY AND MONDAY NIGHT FROM A HIGH SLIDING OUT
OF CENTRAL CANADA AND ACROSS NORTHERN ONTARIO. LIGHT NORTHERLY FLOW
BELOW THE SUBSIDENCE INVERSION AROUND 3-4KFT WILL KEEP LOW CLOUDS
DRIFTING SOUTH ACROSS MUCH OF THE AREA MONDAY AND POSSIBLE INTO
MONDAY NIGHT. WITH 925-900MB TEMPS AROUND -12C...THERE WILL LIKELY
BE ENOUGH SUPPORT FOR A FEW LIGHT SNOW SHOWERS OR FLURRIES...BUT
THINK THE LIMITED CLOUD DEPTH WILL LIMIT BOTH COVERAGE AND
INTENSITY. AS WINDS WEAKEN HEADING INTO MONDAY NIGHT...DRIER AIR
APPEARS TO START WORKING INTO THE AREA AND SHOULD AT LEAST BREAK UP
SOME OF THE CLOUDS AWAY FROM THE LAKE/TERRAIN INFLUENCES OVER THE
NORTHERN PART OF THE CWA. HAVE CONTINUED THE DOWNWARD TREND IN POPS
THROUGH THE NIGHT...BUT DID LIKE THE IDEA SHOWN BY THE PREVIOUS
SHIFT TO HAVE SOME SLIGHT CHANCES WORK BACK INTO THE NORTH CENTRAL
TUESDAY MORNING...AS ANOTHER POCKET OF LOW LEVEL MOISTURE ROTATES
INTO THE AREA AND WINDS SHIFT BACK TO A FAVORABLE UPSLOPE NORTHEAST
WIND.
FOCUS THEN TURNS TO THE SHORTWAVE TROUGH THAT WILL COME ONSHORE
OVER THE PACIFIC NORTHWEST LATE TONIGHT AND MONDAY. THE SHORTWAVE
WILL SLIDE EAST THROUGH THE NORTHERN PLAINS ON TUESDAY AND
REDEVELOP A WEAK SURFACE LOW IN THE PLAINS. AS THESE FEATURES SHIFT
EAST ACROSS THE AREA TUESDAY NIGHT...AN INITIAL PUSH OF
PRECIPITATION WILL SHIFT ACROSS THE UPPER GREAT LAKES REGION (AIDED
BY MID LEVEL WARM AIR ADVECTION). OVERALL...MODELS IN DECENT
AGREEMENT WITH THE TIMING OF THE FORCING (ARRIVING LATE TUESDAY
AFTERNOON AND PUSHING THROUGH LARGELY DURING THE EVENING AND EARLY
OVERNIGHT HOURS. WILL FOLLOW THAT FOR TIMING OF THE PRECIPITATION
AND CONTINUE TO SHOW A PERIOD OF LIKELY VALUES FOR TUESDAY NIGHT.
ALTHOUGH THERE ARE SLIGHT DIFFERENCES IN THE QPF FIELDS (DUE TO THE
DIFFERENCES IN THE EMBEDDED PIECES OF ENERGY AND WHETHER THEY STAY
SOUTH OF OR MOVE THROUGH THE CWA)...IT APPEARS MUCH OF THE CWA WILL
SEE BETWEEN 0.1-0.2 INCH OF QPF. WILL NEED TO WATCH THE THERMAL
PROFILE...AS MUCH OF THE FORCING RIGHT NOW IS ON THE EDGE OF THE
DGZ AND HIGHER SNOW RATIOS. WILL FOLLOW A GENERAL 13-15 TO 1 FOR
NOW...WHICH WOULD LEAD TO 1-3.5 INCHES OF SNOWFALL THROUGH TUESDAY
NIGHT.
EXPECT A BRIEF PERIOD LULL IN THE PRECIPITATION LATE TUESDAY NIGHT
AND WEDNESDAY MORNING BEFORE THE COLD AIR SURGES INTO THE AREA
UNDER INCREASING NORTHWESTERLY WINDS AS A STRONG NORTHERN STREAM
SHORTWAVE DIVES SOUTHEAST ACROSS THE AREA. THIS WILL USHER IN
SIGNIFICANTLY COLDER AIR...850MB TEMPS FALLING FROM -10C TUESDAY
NIGHT TO -22C WEDNESDAY NIGHT...AND LEAD TO THE DEVELOPMENT OF LAKE
EFFECT. WITH THE ADDITIONAL MOISTURE AND STEEPENING LOW LEVEL LAPSE
RATES (LAKE EQUILIBRIUM LEVELS RISING TO AROUND 8KFT) ASSOCIATED
WITH THE SHORTWAVE AND COLDER AIR MOVING INTO THE AREA...EXPECT A
PERIOD OF MODERATE LAKE EFFECT SNOW LATE WEDNESDAY AFTERNOON AND
INTO WEDNESDAY NIGHT. WHILE IT WILL INITIALLY BE IN THE NORTHWEST
WIND SNOWBELTS...QUICKLY VEERING WINDS TO THE NORTH WEDNESDAY
EVENING WILL FOCUS THE SNOW IN THOSE FAVORED AREAS. WILL FOCUS THE
HIGHEST POPS/SNOWFALL OVER THE NORTH CENTRAL (AND NORTHERN PARTS
OF THE KEWEENAW PENINSULA) WHERE THE LONGEST ICE FREE FETCH
IS LOCATED...WITH LESSER AMOUNTS OVER THE WESTERN AREAS DUE TO THE
ICE AROUND ISLE ROYALE SHORTING THE FETCH. WHILE MUCH OF THE
FORCING WILL BE IN THE DGZ DURING THIS FAVORABLE PERIOD OF LAKE
EFFECT...THINK THE STRONG WINDS (25-35KTS) WILL FRACTURE THE FLAKES
AND LIMIT THE ACCUMULATIONS SOME. BUT THIS WILL LEAD TO INCREASED
VISIBILITY REDUCTION AND WILL CONTINUE THAT HEIGHTENED WORDING IN
THE HWO. EXPECT THE SNOW INTENSITY TO QUICKLY DIMINISH FROM WEST TO
EAST ON THURSDAY...AS AN APPROACHING HIGH PRESSURE RIDGE FROM
CENTRAL CANADA LOWERS INVERSION HEIGHTS AND BRINGS DRIER AIR INTO
THE AREA. WITH THE COLD AIR IN PLACE ON THURSDAY (HIGHS IN THE
SINGLE DIGITS AND LOWER TEENS ABOVE ZERO)...THURSDAY NIGHT LOOKS TO
BE A COLD NIGHT WHERE SKIES CLEAR OUT AWAY FROM ANY LINGERING LAKE
EFFECT. THEREFORE...HAVE TRENDED LOWS DOWN SEVERAL DEGREES OVER THE
INTERIOR WEST (INTO THE TEENS BELOW ZERO) AND COULD SEE TEMPS NEAR
WHAT OCCURRED A FEW MORNINGS AGO (-20S IN THE COLD SPOTS) IF THE
HIGH CLOUDS FROM THE NEXT SHORTWAVE HOLD OFF LONG ENOUGH.
THE AREA OF HIGH PRESSURE WILL SLIDE SOUTHEAST OF THE AREA ON
FRIDAY...AS ANOTHER SHORTWAVE DIVES SOUTHEAST ACROSS THE AREA
THAT AFTERNOON. EXPECT ANY SNOWFALL AMOUNTS TO BE LIGHT DUE TO
THE LIMITED MOISTURE AVAILABLE...BUT IT WILL USHER IN ANOTHER
PERIOD OF LAKE EFFECT SNOW FOR LATER FRIDAY NIGHT AND SATURDAY.
LOOKING FARTHER OUT INTO THE FUTURE...LOOKS LIKE LITTLE CHANGE TO
THE OVERALL PATTERN (RIDGE OVER THE WEST AND TROUGH OVER EASTERN
CANADA) SO THE BELOW NORMAL TEMPERATURES LOOK TO CONTINUE INTO NEXT
WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1256 PM EST SUN FEB 8 2015
OFF AND ON SNOW SHOWERS CONTINUE AT ALL 3 SITES. WITH THE ADDITION
OF DAYTIME MIXING CEILINGS HAVE BEEN ABLE TO RISE TO MVFR AT LEAST
TEMPORARILY. THIS WILL LIKELY BE SHORT LIVED AT SAW AS THE NEXT BAND
OF LIGHT TO MODERATE SNOW ORIENTED MAINLY W-E JUST OFFSHORE SINKS TO
THE S AROUND 2KTS/HR...AND BRINGS SAW BACK TO IFR VIS AND BORDERLINE
MVFR/IFR CEILINGS FROM AROUND 20 ON. AM LESS CONFIDENT IN THE
CEILING FCST OVERNIGHT AS VFR CONDITIONS COULD RETURN A LITTLE
EARLIER THAN FCST /CURRENTLY 09-11Z/. LIGHT WINDS AND VFR CONDITIONS
ARE ANTICIPATED 12-18Z MONDAY. COULD STILL HAVE SOME LIGHT SNOW OR
FLURRIES AT BOTH CMX AND SAW LINGERING THROUGH THE PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 1256 PM EST SUN FEB 8 2015
A RIDGE WILL REMAIN ACROSS LAKE SUPERIOR THROUGH TUESDAY...EXTENDING
FROM 2 AREAS OF HIGH PRESSURE CROSSING CENTRAL AND EASTERN CANADA.
THE RESULT WILL BE SLOWLY DIMINISHING WINDS WITH GUSTS FALLING BELOW
25KTS THIS EVENING THROUGH TUESDAY...AND THE TEMPORARY END TO HEAVY
FREEZING SPRAY.
LOW PRESSURE ACROSS THE CENTRAL PLAINS TUESDAY WILL SLIDE ACROSS THE
UPPER GREAT LAKES LATE TUESDAY NIGHT INTO WEDNESDAY...AND THE LOWER
GREAT LAKES WEDNESDAY NIGHT...BEFORE MOVING OFF INTO THE NJ SHORE ON
THURSDAY. IT WILL THEN DEEPEN OFF THE COAST OF MAINE THURSDAY NIGHT
AND FRIDAY. IN THE MEANTIME...A STRONG HIGH ACROSS SASKATCHEWAN ON
WEDNESDAY WILL SINK TO MANITOBA AND THE DAKOTAS WEDNESDAY
NIGHT...THE UPPER GREAT LAKES THURSDAY NIGHT...AND THE OHIO VALLEY
ON FRIDAY. LOOK FOR THE RETURN OF N GALES NEARING 35-40KTS LATE
WESNESDAY AFTERNOON THROUGH WEDNESDAY NIGHT OVER MAINLY CENTRAL AND
E LAKE SUPERIOR /ALONG WITH HEAVY FREEZING SPRAY/.
EXPECT A LOW OVER MANITOBA THURSDAY NIGHT TO THEN MOVE ACROSS LAKE
SUPERIOR ON FRIDAY...BUT AT THIS POINT THE LOW LOOKS PRETTY
WEAK...WITH GUSTS LESS THAN 30KTS EXPECTED THURSDAY AFTERNOON
THROUGH FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST /NOON CST/ THIS
AFTERNOON FOR LSZ162-263-264-266.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KF
SHORT TERM...VOSS
LONG TERM...SRF
AVIATION...KF
MARINE...KF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1253 PM EST SUN FEB 8 2015
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 315 AM EST SUN FEB 8 2015
A WEAK LOW PRESSURE SYSTEM MOVING THROUGH THE LOWER GREAT LAKES
REGION WILL BRING JUST A SMALL CHANCE OF MIXED LIGHT WINTRY
PRECIPITATION TODAY. COLDER AIR WILL MOVE IN THIS AFTERNOON AND
EVENING. DRY WEATHER IS ANTICIPATED MONDAY THROUGH TUESDAY AS HIGH
PRESSURE BUILDS IN. TEMPERATURES WILL BRIEFLY MODERATE FOR THE
MIDDLE OF NEXT WEEK BEFORE MUCH COLDER AIR MOVES IN LATE IN THE
WEEK THROUGH NEXT WEEKEND.
&&
.UPDATE...
ISSUED AT 1139 AM EST SUN FEB 8 2015
PRECIPITATION THIS AFTERNOON AND EVENING IS STILL EXPECTED TO BE
LIGHT PER THE LATEST RUNS OF THE HRRR AND THE 4KM NAM. GIVEN
SOUNDINGS THOUGH...NEED TO HAVE QUITE THE MIX IN THE FORECAST.
SNOW...SLEET...FREEZING RAIN AND EVEN RAIN ARE ALL POSSIBLE...THE
LATER ALONG I94. THERE IS A DRY WEDGE ABOVE THE STRATUS WHICH AS
WET BULB AFFECTS OCCUR WE SHOULD SEE A WINTRY MIX TAKE PLACE. NOT
EXPECTING CONDITIONS TO RISE TO THE LEVEL OF A WINTER WEATHER
ADVISORY GIVEN THE SPOTTY AND OVERALL LIGHT NATURE OF THE
PRECIPITATION. EXPECTING SOME BRIEF BURSTS OF PRECIPITATION AT
TIMES GIVEN RADAR IMAGERY THIS MORNING AND THE LOOK THE HRRR
SIMULATED REFLECTIVITY GOING FORWARD. ISABELLA COUNTY 911 HAS
CONFIRMED SOME LIGHT FREEZING RAIN WITH THE BURST THAT RECENTLY
WENT THROUGH THERE.
HAVE UPDATED THE HAZARDOUS WEATHER OUTLOOK AND ZONE FORECASTS TO
COVER THE LIGHT MYRIAD OF PRECIPITATION. PLAN IS TO COVER WEATHER
THREATS THROUGH THE AFTERNOON AND EVENING WITH SPECIAL WEATHER
STATEMENTS...THE FIRST OF WHICH WAS JUST ISSUED. TEMPERATURES
SHOULD GRADUALLY FALL THROUGH THE AFTERNOON AS A LOW DRIFTS
SOUTHWARD ACROSS THE OHIO VALLEY. NORTHEAST WINDS SHOULD FUNNEL
THE COLDER AIR IN WITH TEENS CURRENTLY AT THE TIP OF THE MITT.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 315 AM EST SUN FEB 8 2015
A WEAK LOW PRESSURE SYSTEM WILL BRING A CHANCE OF LIGHT MIXED
PCPN TODAY. HOWEVER ANY PCPN WILL BE LIGHT AND SCATTERED AND MOST
OF THE DAY SHOULD BE MOSTLY CLOUDY BUT DRY. TEMPS WILL FALL
SLOWLY LATE THIS MORNING THROUGH THE AFTERNOON CHANGING ANY LIGHT
MIXED PCPN OVER TO A FEW VERY LIGHT SNOW SHOWERS AND FLURRIES WITH
NO SNOW ACCUMULATIONS.
HIGH PRESSURE WILL BUILD IN MONDAY THROUGH TUESDAY AND PRODUCE
FAIR WX WITH MOSTLY CLOUDY TO PARTLY CLOUDY SKIES AND SEASONABLY
COLD TEMPS. MAX TEMPS WILL REACH THE TWENTIES BOTH DAYS WITH MIN
TEMPS IN THE SINGLE DIGITS TO TEENS.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 315 AM EST SUN FEB 8 2015
NO BIG STORMS IN THE EXTENDED PERIOD BUT A CLIPPER AND ARCTIC FRONT
WILL WILL BRING SOME SNOW ON WEDNESDAY. THERE WILL BE A PERIOD
OF LAKE EFFECT SNOW WEDNESDAY NIGHT BEFORE WINDS GO NORTHEAST.
THEN ARCTIC HIGH PRESSURE BUILDS IN WITH SUB ZERO COLD THURSDAY
NIGHT. WARM AIR ADVECTION BEGINS FRIDAY WITH MORE LIGHT SNOW MOVING
IN FRIDAY NIGHT AS ANOTHER CLIPPER MOVES THROUGH FOLLOWED BY WHAT
COULD BE SOME OF THE COLDEST AIR OF THE WINTER ON SATURDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1253 PM EST SUN FEB 8 2015
PLENTY OF IMPACTS EXPECTED FOR AVIATION INTERESTS FOR THE FIRST
PORTION OF THE 18Z FCST PERIOD. MOST SITES HAVE DROPPED INTO THE
IFR AND LOWER CATEGORY AT PRESS TIME WITH CIGS AND VSBYS. KJXN HAS
NOT YET AS OF 1730Z...HOWEVER WE EXPECT THEM TO DROP TO IFR SHORTLY.
NOT A LOT OF PCPN AROUND THE AREA...HOWEVER THERE HAVE BEEN SOME
POCKETS OF VERY LIGHT PCPN FLOATING THROUGH THE AREA. THIS HAS
BEEN SOME MIST/DRIZZLE/FREEZING DRIZZLE DEPENDING ON THE SFC TEMP.
WE EXPECT THIS TO CONTINUE UNTIL ABOUT 21Z OR SO. AROUND 21Z THERE
HAS BEEN GOOD CONSISTENCY IN DATA THAT A NARROW YET SOMEWHAT
INTENSE BAND OF SNOW WILL MOVE THROUGH FROM NW TO SE. WE HAVE
TRIED TO ACCOUNT FOR THIS IN THE FCST.
ONCE THE SNOW MOVES OUT OF ALL AREAS BY 02Z OR SO...WE SHOULD SEE
A LOW CLOUD DECK HANG AROUND MOST OF THE REMAINDER OF THE FCST
PERIOD. THIS LOOKS TO BE MVFR...BUT IT IS POSSIBLE IT COULD BE IFR
FOR A PERIOD. EVENTUALLY WE WILL LIKELY START BREAKING OUT OF THE
LOWER CLOUDS DURING THE DAY ON MON...TOWARD THE END OF THE FCST PERIOD.
&&
.HYDROLOGY...
ISSUED AT 1103 AM EST SUN FEB 8 2015
ICE IS STABLE ON AREA RIVERS AS THE RECENT WARM-UP HAS NOT BEEN
SIGNIFICANT ENOUGH TO MELT AWAY OR CRACK AND SPLIT THE ICE TO GET
THINGS MOVING ON THE RIVERS. AVERAGE TEMPERATURES (HIGH + LOW / 2)
FOR EARLY IN THE WEEK WILL BE IN THE MID TEENS TO LOW 20S...THEN
DROPPING TO THE SINGLE FIGURES AND LOW TEENS FOR THE SECOND HALF OF
THE WEEK. THIS WILL YIELD EXCELLENT ICE FORMATION ON AREA
RIVERS...ESPECIALLY THE SECOND HALF OF THE WEEK. LOW TEMPERATURES
THURSDAY NIGHT AND SATURDAY NIGHT WILL BE BELOW ZERO AWAY FROM LAKE
MICHIGAN. SNOW ACCUMULATIONS COULD AID IN ICE DEVELOPMENT AS
WELL...ALTHOUGH AN INCREASINGLY STEEPER SUN ANGLE COULD MITIGATE
SOME OF THAT ADDITIONAL DEVELOPMENT. ICE SHOULD LARGELY REMAIN
STATUS QUO UNTIL A SIGNIFICANT WARM UP HELPS BREAK IT UP.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...DUKE
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...OSTUNO
AVIATION...NJJ
HYDROLOGY...HOVING
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1139 AM EST SUN FEB 8 2015
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 315 AM EST SUN FEB 8 2015
A WEAK LOW PRESSURE SYSTEM MOVING THROUGH THE LOWER GREAT LAKES
REGION WILL BRING JUST A SMALL CHANCE OF MIXED LIGHT WINTERY
PRECIPITATION TODAY. COLDER AIR WILL MOVE IN THIS AFTERNOON AND
EVENING. DRY WEATHER IS ANTICIPATED MONDAY THROUGH TUESDAY AS HIGH
PRESSURE BUILDS IN. TEMPERATURES WILL BRIEFLY MODERATE FOR THE
MIDDLE OF NEXT WEEK BEFORE MUCH COLDER AIR MOVES IN LATE IN THE
WEEK THROUGH NEXT WEEKEND.
&&
.UPDATE...
ISSUED AT 1139 AM EST SUN FEB 8 2015
PRECIPITATION THIS AFTERNOON AND EVENING IS STILL EXPECTED TO BE
LIGHT PER THE LATEST RUNS OF THE HRRR AND THE 4KM NAM. GIVEN
SOUNDINGS THOUGH...NEED TO HAVE QUITE THE MIX IN THE FORECAST.
SNOW...SLEET...FREEZING RAIN AND EVEN RAIN ARE ALL POSSIBLE...THE
LATER ALONG I94. THERE IS A DRY WEDGE ABOVE THE STRATUS WHICH AS
WET BELB AFFECTS OCCUR WE SHOULD SEE A WINTRY MIX TAKE PLACE. NOT
EXPECTING CONDITIONS TO RISE TO THE LEVEL OF A WINTER WEATHER
ADVISORY GIVEN THE SPOTTY AND OVERALL LIGHT NATURE OF THE
PRECIPITATION. EXPECTING SOME BRIEF BURSTS OF PRECIPITATION AT
TIMES GIVEN RADAR IMAGERY THIS MORNING AND THE LOOK THE HRRR
SIMULATED REFLECTIVITY GOING FORWARD. ISABELLA COUNTY 911 HAS
CONFIRMED SOME LIGHT FREEZING RAIN WITH THE BURST THAT RECENTLY
WENT THROUGH THERE.
HAVE UPDATED THE HAZARDOUS WEATHER OUTLOOK AND ZONE FORECASTS TO
COVER THE LIGHT MYRIAD OF PRECIPITATION. PLAN IS TO COVER WEATHER
THREATS THROUGH THE AFTERNOON AND EVENING WITH SPECIAL WEATHER
STATEMENTS...THE FIRST OF WHICH WAS JUST ISSUED. TEMPERATURES
SHOULD GRADUALLY FALL THROUGH THE AFTERNOON AS A LOW DRIFTS
SOUTHWARD ACROSS THE OHIO VALLEY. NORTHEAST WINDS SHOULD FUNNEL
THE COLDER AIR IN WITH TEENS CURRENTLY AT THE TIP OF THE MITT.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 315 AM EST SUN FEB 8 2015
A WEAK LOW PRESSURE SYSTEM WILL BRING A CHANCE OF LIGHT MIXED
PCPN TODAY. HOWEVER ANY PCPN WILL BE LIGHT AND SCATTERED AND MOST
OF THE DAY SHOULD BE MOSTLY CLOUDY BUT DRY. TEMPS WILL FALL
SLOWLY LATE THIS MORNING THROUGH THE AFTERNOON CHANGING ANY LIGHT
MIXED PCPN OVER TO A FEW VERY LIGHT SNOW SHOWERS AND FLURRIES WITH
NO SNOW ACCUMULATIONS.
HIGH PRESSURE WILL BUILD IN MONDAY THROUGH TUESDAY AND PRODUCE
FAIR WX WITH MOSTLY CLOUDY TO PARTLY CLOUDY SKIES AND SEASONABLY
COLD TEMPS. MAX TEMPS WILL REACH THE TWENTIES BOTH DAYS WITH MIN
TEMPS IN THE SINGLE DIGITS TO TEENS.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 315 AM EST SUN FEB 8 2015
NO BIG STORMS IN THE EXTENDED PERIOD BUT A CLIPPER AND ARCTIC FRONT
WILL WILL BRING SOME SNOW ON WEDNESDAY. THERE WILL BE A PERIOD
OF LAKE EFFECT SNOW WEDNESDAY NIGHT BEFORE WINDS GO NORTHEAST.
THEN ARCTIC HIGH PRESSURE BUILDS IN WITH SUB ZERO COLD THURSDAY
NIGHT. WARM AIR ADVECTION BEGINS FRIDAY WITH MORE LIGHT SNOW MOVING
IN FRIDAY NIGHT AS ANOTHER CLIPPER MOVES THROUGH FOLLOWED BY WHAT
COULD BE SOME OF THE COLDEST AIR OF THE WINTER ON SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 643 AM EST SUN FEB 8 2015
MVFR CONDITIONS EARLY THIS MORNING WILL GO TO IFR AS STRATUS WITH
BASES AROUND 800 FEET AGL MOVES IN BY 18Z. CONDITIONS WILL VARY
BETWEEN LIFR...IFR AND MVFR THROUGH THE AFTERNOON. SOME LIGHT
PRECIPITATION IS POSSIBLE BUT SHOULD NOT HAVE ANY IMPACT AND WAS
LEFT OUT THE FORECAST. WINDS WILL BE GOING NORTHEAST THIS MORNING
AOB 10 KNOTS.
&&
.HYDROLOGY...
ISSUED AT 1103 AM EST SUN FEB 8 2015
ICE IS STABLE ON AREA RIVERS AS THE RECENT WARM-UP HAS NOT BEEN
SIGNIFICANT ENOUGH TO MELT AWAY OR CRACK AND SPLIT THE ICE TO GET
THINGS MOVING ON THE RIVERS. AVERAGE TEMPERATURES (HIGH + LOW / 2)
FOR EARLY IN THE WEEK WILL BE IN THE MID TEENS TO LOW 20S...THEN
DROPPING TO THE SINGLE FIGURES AND LOW TEENS FOR THE SECOND HALF OF
THE WEEK. THIS WILL YIELD EXCELLENT ICE FORMATION ON AREA
RIVERS...ESPECIALLY THE SECOND HALF OF THE WEEK. LOW TEMPERATURES
THURSDAY NIGHT AND SATURDAY NIGHT WILL BE BELOW ZERO AWAY FROM LAKE
MICHIGAN. SNOW ACCUMULATIONS COULD AID IN ICE DEVELOPMENT AS
WELL...ALTHOUGH AN INCREASINGLY STEEPER SUN ANGLE COULD MITIGATE
SOME OF THAT ADDITIONAL DEVELOPMENT. ICE SHOULD LARGELY REMAIN
STATUS QUO UNTIL A SIGNIFICANT WARM UP HELPS BREAK IT UP.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...DUKE
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...OSTUNO
AVIATION...OSTUNO
HYDROLOGY...HOVING
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1007 AM EST SUN FEB 8 2015
.UPDATE...
ISSUED AT 1007 AM EST SUN FEB 8 2015
FCST MODEL SNOW RATIOS FOR THE BAND OF FLUFFY SNOW ARE WAY
OFF...MORE LIKE 25:1 AND NOT THE 15:1 SHOWN OFF THE NAM/BUFKIT. AS A
RESULT...WE HAVE SEEN 1 IN/HR ACCUMULATIONS ALREADY OVER THE DEAD
RIVER BASIN. WENT AHEAD AND INCREASED NOT ONLY RATIOS...BUT
QPF...AND SNOW AMOUNTS. GOING WITH AROUND 2IN OVER THE HIGHER ACROSS
THE KEWEENAW PENINSULA AND MARQUETTE COUNTY FROM THE HURON MOUNTAINS
THROUGH NEGAUNEE/ISHPEMING. WHILE MOISTURE DOES SLOWLY DECREASE AND
INVERSION HEIGHTS WILL BE LOWERING EVEN MORE /BELOW 4KFT...THIS AREA
IS IN THE DGZ. CONTINUED LIGHT LES WILL BE THE RULE. UPDATES WERE
MADE TO THE ONGOING FCST FOR THIS BETWEEN 830 AND 930AM.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 418 AM EST SUN FEB 8 2015
IT APPEARS THAT MUCH OF THE FREEZING DRIZZLE FROM LAST EVENING/EARLY
OVERNIGHT HAS TURNED OVER TO LIGHT -SHSN OR FLURRIES ACROSS MUCH OF
THE CWA AS TEMPS HAVE COOLED BLO -10C IN THE LOWEST 2KFT OF THE
AIRMASS PER RAP SOUNDINGS. IF THERE IS ANY REMAINING -FZDZ OVER SE
SECTIONS IT SHOULD BE GONE BY SUNRISE WITH THE COOLER TEMPS ALLOWING
FOR ICE CRYSTAL FORMATION IN THE CONVECTIVE LAYER.
NE FLOW AND TEMPS TO NEAR -15C WITHIN THE LOWEST 3KFT OF ATMOSPHERE
WILL FAVOR 4 WRN COUNTIES AND WRN MQT-BARAGA COUNTIES FOR LIGHT LES
TODAY. LIMITING FACTOR BESIDES FAIRLY MARGINAL INSTABILITY WILL BE
INVERSION WITHIN LOWEST 3KFT SO NOT EXPECTING MUCH IN THE WAY OF
ACCUMULATION WITH A DUSTING TO MAYBE AN INCH FOR AREAS BEST AIDED BY
UPSLOPE NE FLOW. MAX TEMPS TODAY WILL GENERALLY RANGE FROM THE TEENS
NORTH TO LOWER 20S ALONG THE WI BORDER.
WITH SHORTWAVE RIDGE AND SFC RIDGE MOVING OVERHEAD...EXPECT
SIGNIFICANT DRYING/SUBSIDENCE ALOFT TONIGHT. NAM SNDGS SHOW MOISTURE
SHALLOWING OUT BLO LOWEST 2KFT FM SFC...BUT WITH TEMP AT INVERSION
BASE OF -13 TO -14C...THERE WILL LIKELY BE SOME LIGHT LES/FLURRIES
OFF THE LAKE...ESPECIALLY FOR UPSLOPE NE TO N FLOW AREAS. STILL
WOULDN/T EXPECT ACCUMULATION ANY MORE THAN HALF AN INCH. WITH LIGHT
ERLY FLOW SETTING UP OVER FAR ERN COUNTIES THERE COULD BE SOME
CLEARING TO ALLOW TEMPS TO FALL FM 5 TO 10 BELOW ZERO AT SOME OF
TYPICAL COLD SPOTS. OVER THE WEST HALF AND SOUTH CENTRAL...TEMPS
WILL RANGE FROM THE SINGLE DIGITS ABV ZERO INLAND TO 10F OR HIGHER
NEAR THE GREAT LAKES SHORELINES.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 401 AM EST SUN FEB 8 2015
MUCH OF THE FOCUS DURING THE LONG TERM FORECAST WILL BE WITH THE
LOW PRESSURE SYSTEM MOVING EAST THROUGH THE GREAT LAKES REGION
TUESDAY NIGHT AND THEN THE COLD AIR SURGING SOUTH INTO THE AREA AND
LEADING TO ANOTHER PERIOD OF MODERATE LAKE EFFECT SNOW WEDNESDAY
AFTERNOON INTO THURSDAY MORNING.
BEFORE THE ACTIVE WEATHER DURING THE MIDDLE OF THE WEEK...THE AREA
WILL BE UNDER A WEAK SURFACE RIDGE THAT WILL BE MOVING ACROSS THE
UPPER GREAT LAKES MONDAY AND MONDAY NIGHT FROM A HIGH SLIDING OUT
OF CENTRAL CANADA AND ACROSS NORTHERN ONTARIO. LIGHT NORTHERLY FLOW
BELOW THE SUBSIDENCE INVERSION AROUND 3-4KFT WILL KEEP LOW CLOUDS
DRIFTING SOUTH ACROSS MUCH OF THE AREA MONDAY AND POSSIBLE INTO
MONDAY NIGHT. WITH 925-900MB TEMPS AROUND -12C...THERE WILL LIKELY
BE ENOUGH SUPPORT FOR A FEW LIGHT SNOW SHOWERS OR FLURRIES...BUT
THINK THE LIMITED CLOUD DEPTH WILL LIMIT BOTH COVERAGE AND
INTENSITY. AS WINDS WEAKEN HEADING INTO MONDAY NIGHT...DRIER AIR
APPEARS TO START WORKING INTO THE AREA AND SHOULD AT LEAST BREAK UP
SOME OF THE CLOUDS AWAY FROM THE LAKE/TERRAIN INFLUENCES OVER THE
NORTHERN PART OF THE CWA. HAVE CONTINUED THE DOWNWARD TREND IN POPS
THROUGH THE NIGHT...BUT DID LIKE THE IDEA SHOWN BY THE PREVIOUS
SHIFT TO HAVE SOME SLIGHT CHANCES WORK BACK INTO THE NORTH CENTRAL
TUESDAY MORNING...AS ANOTHER POCKET OF LOW LEVEL MOISTURE ROTATES
INTO THE AREA AND WINDS SHIFT BACK TO A FAVORABLE UPSLOPE NORTHEAST
WIND.
FOCUS THEN TURNS TO THE SHORTWAVE TROUGH THAT WILL COME ONSHORE
OVER THE PACIFIC NORTHWEST LATE TONIGHT AND MONDAY. THE SHORTWAVE
WILL SLIDE EAST THROUGH THE NORTHERN PLAINS ON TUESDAY AND
REDEVELOP A WEAK SURFACE LOW IN THE PLAINS. AS THESE FEATURES SHIFT
EAST ACROSS THE AREA TUESDAY NIGHT...AN INITIAL PUSH OF
PRECIPITATION WILL SHIFT ACROSS THE UPPER GREAT LAKES REGION (AIDED
BY MID LEVEL WARM AIR ADVECTION). OVERALL...MODELS IN DECENT
AGREEMENT WITH THE TIMING OF THE FORCING (ARRIVING LATE TUESDAY
AFTERNOON AND PUSHING THROUGH LARGELY DURING THE EVENING AND EARLY
OVERNIGHT HOURS. WILL FOLLOW THAT FOR TIMING OF THE PRECIPITATION
AND CONTINUE TO SHOW A PERIOD OF LIKELY VALUES FOR TUESDAY NIGHT.
ALTHOUGH THERE ARE SLIGHT DIFFERENCES IN THE QPF FIELDS (DUE TO THE
DIFFERENCES IN THE EMBEDDED PIECES OF ENERGY AND WHETHER THEY STAY
SOUTH OF OR MOVE THROUGH THE CWA)...IT APPEARS MUCH OF THE CWA WILL
SEE BETWEEN 0.1-0.2 INCH OF QPF. WILL NEED TO WATCH THE THERMAL
PROFILE...AS MUCH OF THE FORCING RIGHT NOW IS ON THE EDGE OF THE
DGZ AND HIGHER SNOW RATIOS. WILL FOLLOW A GENERAL 13-15 TO 1 FOR
NOW...WHICH WOULD LEAD TO 1-3.5 INCHES OF SNOWFALL THROUGH TUESDAY
NIGHT.
EXPECT A BRIEF PERIOD LULL IN THE PRECIPITATION LATE TUESDAY NIGHT
AND WEDNESDAY MORNING BEFORE THE COLD AIR SURGES INTO THE AREA
UNDER INCREASING NORTHWESTERLY WINDS AS A STRONG NORTHERN STREAM
SHORTWAVE DIVES SOUTHEAST ACROSS THE AREA. THIS WILL USHER IN
SIGNIFICANTLY COLDER AIR...850MB TEMPS FALLING FROM -10C TUESDAY
NIGHT TO -22C WEDNESDAY NIGHT...AND LEAD TO THE DEVELOPMENT OF LAKE
EFFECT. WITH THE ADDITIONAL MOISTURE AND STEEPENING LOW LEVEL LAPSE
RATES (LAKE EQUILIBRIUM LEVELS RISING TO AROUND 8KFT) ASSOCIATED
WITH THE SHORTWAVE AND COLDER AIR MOVING INTO THE AREA...EXPECT A
PERIOD OF MODERATE LAKE EFFECT SNOW LATE WEDNESDAY AFTERNOON AND
INTO WEDNESDAY NIGHT. WHILE IT WILL INITIALLY BE IN THE NORTHWEST
WIND SNOWBELTS...QUICKLY VEERING WINDS TO THE NORTH WEDNESDAY
EVENING WILL FOCUS THE SNOW IN THOSE FAVORED AREAS. WILL FOCUS THE
HIGHEST POPS/SNOWFALL OVER THE NORTH CENTRAL (AND NORTHERN PARTS
OF THE KEWEENAW PENINSULA) WHERE THE LONGEST ICE FREE FETCH
IS LOCATED...WITH LESSER AMOUNTS OVER THE WESTERN AREAS DUE TO THE
ICE AROUND ISLE ROYALE SHORTING THE FETCH. WHILE MUCH OF THE
FORCING WILL BE IN THE DGZ DURING THIS FAVORABLE PERIOD OF LAKE
EFFECT...THINK THE STRONG WINDS (25-35KTS) WILL FRACTURE THE FLAKES
AND LIMIT THE ACCUMULATIONS SOME. BUT THIS WILL LEAD TO INCREASED
VISIBILITY REDUCTION AND WILL CONTINUE THAT HEIGHTENED WORDING IN
THE HWO. EXPECT THE SNOW INTENSITY TO QUICKLY DIMINISH FROM WEST TO
EAST ON THURSDAY...AS AN APPROACHING HIGH PRESSURE RIDGE FROM
CENTRAL CANADA LOWERS INVERSION HEIGHTS AND BRINGS DRIER AIR INTO
THE AREA. WITH THE COLD AIR IN PLACE ON THURSDAY (HIGHS IN THE
SINGLE DIGITS AND LOWER TEENS ABOVE ZERO)...THURSDAY NIGHT LOOKS TO
BE A COLD NIGHT WHERE SKIES CLEAR OUT AWAY FROM ANY LINGERING LAKE
EFFECT. THEREFORE...HAVE TRENDED LOWS DOWN SEVERAL DEGREES OVER THE
INTERIOR WEST (INTO THE TEENS BELOW ZERO) AND COULD SEE TEMPS NEAR
WHAT OCCURRED A FEW MORNINGS AGO (-20S IN THE COLD SPOTS) IF THE
HIGH CLOUDS FROM THE NEXT SHORTWAVE HOLD OFF LONG ENOUGH.
THE AREA OF HIGH PRESSURE WILL SLIDE SOUTHEAST OF THE AREA ON
FRIDAY...AS ANOTHER SHORTWAVE DIVES SOUTHEAST ACROSS THE AREA
THAT AFTERNOON. EXPECT ANY SNOWFALL AMOUNTS TO BE LIGHT DUE TO
THE LIMITED MOISTURE AVAILABLE...BUT IT WILL USHER IN ANOTHER
PERIOD OF LAKE EFFECT SNOW FOR LATER FRIDAY NIGHT AND SATURDAY.
LOOKING FARTHER OUT INTO THE FUTURE...LOOKS LIKE LITTLE CHANGE TO
THE OVERALL PATTERN (RIDGE OVER THE WEST AND TROUGH OVER EASTERN
CANADA) SO THE BELOW NORMAL TEMPERATURES LOOK TO CONTINUE INTO NEXT
WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 654 AM EST SUN FEB 8 2015
EXPECT MAINLY MVFR CONDITIONS AT KSAW AND IFR CONDITIONS AT KCMX
AND KIWD THIS MORNING UNDER ENE FLOW. LOOK FOR CONDITIONS TO IMPROVE
TO MVFR AT KCMX AND KIWD AS FLOW BECOMES MORE NE OR DOWNSLOPE BY
AFTERNOON. AT SAME TIME...NNE FLOWWILL MAKE IT MORE FAVORABLE FOR
LAKE EFFECT SNOW SHOWERS AND POSSIBLE IFR CONDITIONS AT KSAW LATE
THIS AFTERNOON. CONTINUED NE FLOW AND DRYING TONIGHT SHOULD ALLOW FOR
MVFR AT ALL SITES WITH SOME LINGERING LAKE FLURRIES POSSIBLE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 418 AM EST SUN FEB 8 2015
TIGHT PRES GRADIENT AND NE WINDS CHANNELING DOWN THE WRN HALF OF THE
LAKE WILL RESULT IN SOLID WINDS TO 30 KT WITH A FEW SPOTS SEEING
GALE FORCE GUSTS THIS MORNING. HIGH WINDS WILL ALSO RESULT IN HEAVY
FREEZING SPRAY FOR WEST AND CENTRAL LAKE SUPERIOR INTO EARLY
AFTERNOON.
PRES GRADIENT WEAKENS BY TONIGHT AND CONTINUES INTO TUESDAY AS HIGH
PRES RIDGE MOVES OVER THE AREA. WINDS WILL BE GENERALLY LESS THAN 20
KT THROUGH THE PD. LIGHT WINDS WILL CONTINUE TUE NIGHT INTO WED
MORNING AS A LOW PRES TROUGH MOVES INTO THE AREA...BUT THEN WINDS
RAMP UP ON THE BACKSIDE OF THE TROUGH WITH NORTH GALES TO 35 KNOTS
EXPECTED ACROSS MUCH OF THE LAKE WED NIGHT. NORTH WINDS SHOULD COME
DOWN BLO GALES ON THU BUT WILL REMAIN UP TO 30 KNOTS OVER THE EAST
HALF.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST /NOON CST/ THIS
AFTERNOON FOR LSZ162-263-264-266.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KF
SHORT TERM...VOSS
LONG TERM...SRF
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
745 AM EST SUN FEB 8 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 418 AM EST SUN FEB 8 2015
IT APPEARS THAT MUCH OF THE FREEZING DRIZZLE FROM LAST EVENING/EARLY
OVERNIGHT HAS TURNED OVER TO LIGHT -SHSN OR FLURRIES ACROSS MUCH OF
THE CWA AS TEMPS HAVE COOLED BLO -10C IN THE LOWEST 2KFT OF THE
AIRMASS PER RAP SOUNDINGS. IF THERE IS ANY REMAINING -FZDZ OVER SE
SECTIONS IT SHOULD BE GONE BY SUNRISE WITH THE COOLER TEMPS ALLOWING
FOR ICE CRYSTAL FORMATION IN THE CONVECTIVE LAYER.
NE FLOW AND TEMPS TO NEAR -15C WITHIN THE LOWEST 3KFT OF ATMOSPHERE
WILL FAVOR 4 WRN COUNTIES AND WRN MQT-BARAGA COUNTIES FOR LIGHT LES
TODAY. LIMITING FACTOR BESIDES FAIRLY MARGINAL INSTABILITY WILL BE
INVERSION WITHIN LOWEST 3KFT SO NOT EXPECTING MUCH IN THE WAY OF
ACCUMULATION WITH A DUSTING TO MAYBE AN INCH FOR AREAS BEST AIDED BY
UPSLOPE NE FLOW. MAX TEMPS TODAY WILL GENERALLY RANGE FROM THE TEENS
NORTH TO LOWER 20S ALONG THE WI BORDER.
WITH SHORTWAVE RIDGE AND SFC RIDGE MOVING OVERHEAD...EXPECT
SIGNIFICANT DRYING/SUBSIDENCE ALOFT TONIGHT. NAM SNDGS SHOW MOISTURE
SHALLOWING OUT BLO LOWEST 2KFT FM SFC...BUT WITH TEMP AT INVERSION
BASE OF -13 TO -14C...THERE WILL LIKELY BE SOME LIGHT LES/FLURRIES
OFF THE LAKE...ESPECIALLY FOR UPSLOPE NE TO N FLOW AREAS. STILL
WOULDN/T EXPECT ACCUMULATION ANY MORE THAN HALF AN INCH. WITH LIGHT
ERLY FLOW SETTING UP OVER FAR ERN COUNTIES THERE COULD BE SOME
CLEARING TO ALLOW TEMPS TO FALL FM 5 TO 10 BELOW ZERO AT SOME OF
TYPICAL COLD SPOTS. OVER THE WEST HALF AND SOUTH CENTRAL...TEMPS
WILL RANGE FROM THE SINGLE DIGITS ABV ZERO INLAND TO 10F OR HIGHER
NEAR THE GREAT LAKES SHORELINES.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 401 AM EST SUN FEB 8 2015
MUCH OF THE FOCUS DURING THE LONG TERM FORECAST WILL BE WITH THE
LOW PRESSURE SYSTEM MOVING EAST THROUGH THE GREAT LAKES REGION
TUESDAY NIGHT AND THEN THE COLD AIR SURGING SOUTH INTO THE AREA AND
LEADING TO ANOTHER PERIOD OF MODERATE LAKE EFFECT SNOW WEDNESDAY
AFTERNOON INTO THURSDAY MORNING.
BEFORE THE ACTIVE WEATHER DURING THE MIDDLE OF THE WEEK...THE AREA
WILL BE UNDER A WEAK SURFACE RIDGE THAT WILL BE MOVING ACROSS THE
UPPER GREAT LAKES MONDAY AND MONDAY NIGHT FROM A HIGH SLIDING OUT
OF CENTRAL CANADA AND ACROSS NORTHERN ONTARIO. LIGHT NORTHERLY FLOW
BELOW THE SUBSIDENCE INVERSION AROUND 3-4KFT WILL KEEP LOW CLOUDS
DRIFTING SOUTH ACROSS MUCH OF THE AREA MONDAY AND POSSIBLE INTO
MONDAY NIGHT. WITH 925-900MB TEMPS AROUND -12C...THERE WILL LIKELY
BE ENOUGH SUPPORT FOR A FEW LIGHT SNOW SHOWERS OR FLURRIES...BUT
THINK THE LIMITED CLOUD DEPTH WILL LIMIT BOTH COVERAGE AND
INTENSITY. AS WINDS WEAKEN HEADING INTO MONDAY NIGHT...DRIER AIR
APPEARS TO START WORKING INTO THE AREA AND SHOULD AT LEAST BREAK UP
SOME OF THE CLOUDS AWAY FROM THE LAKE/TERRAIN INFLUENCES OVER THE
NORTHERN PART OF THE CWA. HAVE CONTINUED THE DOWNWARD TREND IN POPS
THROUGH THE NIGHT...BUT DID LIKE THE IDEA SHOWN BY THE PREVIOUS
SHIFT TO HAVE SOME SLIGHT CHANCES WORK BACK INTO THE NORTH CENTRAL
TUESDAY MORNING...AS ANOTHER POCKET OF LOW LEVEL MOISTURE ROTATES
INTO THE AREA AND WINDS SHIFT BACK TO A FAVORABLE UPSLOPE NORTHEAST
WIND.
FOCUS THEN TURNS TO THE SHORTWAVE TROUGH THAT WILL COME ONSHORE
OVER THE PACIFIC NORTHWEST LATE TONIGHT AND MONDAY. THE SHORTWAVE
WILL SLIDE EAST THROUGH THE NORTHERN PLAINS ON TUESDAY AND
REDEVELOP A WEAK SURFACE LOW IN THE PLAINS. AS THESE FEATURES SHIFT
EAST ACROSS THE AREA TUESDAY NIGHT...AN INITIAL PUSH OF
PRECIPITATION WILL SHIFT ACROSS THE UPPER GREAT LAKES REGION (AIDED
BY MID LEVEL WARM AIR ADVECTION). OVERALL...MODELS IN DECENT
AGREEMENT WITH THE TIMING OF THE FORCING (ARRIVING LATE TUESDAY
AFTERNOON AND PUSHING THROUGH LARGELY DURING THE EVENING AND EARLY
OVERNIGHT HOURS. WILL FOLLOW THAT FOR TIMING OF THE PRECIPITATION
AND CONTINUE TO SHOW A PERIOD OF LIKELY VALUES FOR TUESDAY NIGHT.
ALTHOUGH THERE ARE SLIGHT DIFFERENCES IN THE QPF FIELDS (DUE TO THE
DIFFERENCES IN THE EMBEDDED PIECES OF ENERGY AND WHETHER THEY STAY
SOUTH OF OR MOVE THROUGH THE CWA)...IT APPEARS MUCH OF THE CWA WILL
SEE BETWEEN 0.1-0.2 INCH OF QPF. WILL NEED TO WATCH THE THERMAL
PROFILE...AS MUCH OF THE FORCING RIGHT NOW IS ON THE EDGE OF THE
DGZ AND HIGHER SNOW RATIOS. WILL FOLLOW A GENERAL 13-15 TO 1 FOR
NOW...WHICH WOULD LEAD TO 1-3.5 INCHES OF SNOWFALL THROUGH TUESDAY
NIGHT.
EXPECT A BRIEF PERIOD LULL IN THE PRECIPITATION LATE TUESDAY NIGHT
AND WEDNESDAY MORNING BEFORE THE COLD AIR SURGES INTO THE AREA
UNDER INCREASING NORTHWESTERLY WINDS AS A STRONG NORTHERN STREAM
SHORTWAVE DIVES SOUTHEAST ACROSS THE AREA. THIS WILL USHER IN
SIGNIFICANTLY COLDER AIR...850MB TEMPS FALLING FROM -10C TUESDAY
NIGHT TO -22C WEDNESDAY NIGHT...AND LEAD TO THE DEVELOPMENT OF LAKE
EFFECT. WITH THE ADDITIONAL MOISTURE AND STEEPENING LOW LEVEL LAPSE
RATES (LAKE EQUILIBRIUM LEVELS RISING TO AROUND 8KFT) ASSOCIATED
WITH THE SHORTWAVE AND COLDER AIR MOVING INTO THE AREA...EXPECT A
PERIOD OF MODERATE LAKE EFFECT SNOW LATE WEDNESDAY AFTERNOON AND
INTO WEDNESDAY NIGHT. WHILE IT WILL INITIALLY BE IN THE NORTHWEST
WIND SNOWBELTS...QUICKLY VEERING WINDS TO THE NORTH WEDNESDAY
EVENING WILL FOCUS THE SNOW IN THOSE FAVORED AREAS. WILL FOCUS THE
HIGHEST POPS/SNOWFALL OVER THE NORTH CENTRAL (AND NORTHERN PARTS
OF THE KEWEENAW PENINSULA) WHERE THE LONGEST ICE FREE FETCH
IS LOCATED...WITH LESSER AMOUNTS OVER THE WESTERN AREAS DUE TO THE
ICE AROUND ISLE ROYALE SHORTING THE FETCH. WHILE MUCH OF THE
FORCING WILL BE IN THE DGZ DURING THIS FAVORABLE PERIOD OF LAKE
EFFECT...THINK THE STRONG WINDS (25-35KTS) WILL FRACTURE THE FLAKES
AND LIMIT THE ACCUMULATIONS SOME. BUT THIS WILL LEAD TO INCREASED
VISIBILITY REDUCTION AND WILL CONTINUE THAT HEIGHTENED WORDING IN
THE HWO. EXPECT THE SNOW INTENSITY TO QUICKLY DIMINISH FROM WEST TO
EAST ON THURSDAY...AS AN APPROACHING HIGH PRESSURE RIDGE FROM
CENTRAL CANADA LOWERS INVERSION HEIGHTS AND BRINGS DRIER AIR INTO
THE AREA. WITH THE COLD AIR IN PLACE ON THURSDAY (HIGHS IN THE
SINGLE DIGITS AND LOWER TEENS ABOVE ZERO)...THURSDAY NIGHT LOOKS TO
BE A COLD NIGHT WHERE SKIES CLEAR OUT AWAY FROM ANY LINGERING LAKE
EFFECT. THEREFORE...HAVE TRENDED LOWS DOWN SEVERAL DEGREES OVER THE
INTERIOR WEST (INTO THE TEENS BELOW ZERO) AND COULD SEE TEMPS NEAR
WHAT OCCURRED A FEW MORNINGS AGO (-20S IN THE COLD SPOTS) IF THE
HIGH CLOUDS FROM THE NEXT SHORTWAVE HOLD OFF LONG ENOUGH.
THE AREA OF HIGH PRESSURE WILL SLIDE SOUTHEAST OF THE AREA ON
FRIDAY...AS ANOTHER SHORTWAVE DIVES SOUTHEAST ACROSS THE AREA
THAT AFTERNOON. EXPECT ANY SNOWFALL AMOUNTS TO BE LIGHT DUE TO
THE LIMITED MOISTURE AVAILABLE...BUT IT WILL USHER IN ANOTHER
PERIOD OF LAKE EFFECT SNOW FOR LATER FRIDAY NIGHT AND SATURDAY.
LOOKING FARTHER OUT INTO THE FUTURE...LOOKS LIKE LITTLE CHANGE TO
THE OVERALL PATTERN (RIDGE OVER THE WEST AND TROUGH OVER EASTERN
CANADA) SO THE BELOW NORMAL TEMPERATURES LOOK TO CONTINUE INTO NEXT
WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 654 AM EST SUN FEB 8 2015
EXPECT MAINLY MVFR CONDITIONS AT KSAW AND IFR CONDITIONS AT KCMX
AND KIWD THIS MORNING UNDER ENE FLOW. LOOK FOR CONDITIONS TO IMPROVE
TO MVFR AT KCMX AND KIWD AS FLOW BECOMES MORE NE OR DOWNSLOPE BY
AFTERNOON. AT SAME TIME...NNE FLOWWILL MAKE IT MORE FAVORABLE FOR
LAKE EFFECT SNOW SHOWERS AND POSSIBLE IFR CONDITIONS AT KSAW LATE
THIS AFTERNOON. CONTINUED NE FLOW AND DRYING TONIGHT SHOULD ALLOW FOR
MVFR AT ALL SITES WITH SOME LINGERING LAKE FLURRIES POSSIBLE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 418 AM EST SUN FEB 8 2015
TIGHT PRES GRADIENT AND NE WINDS CHANNELING DOWN THE WRN HALF OF THE
LAKE WILL RESULT IN SOLID WINDS TO 30 KT WITH A FEW SPOTS SEEING
GALE FORCE GUSTS THIS MORNING. HIGH WINDS WILL ALSO RESULT IN HEAVY
FREEZING SPRAY FOR WEST AND CENTRAL LAKE SUPERIOR INTO EARLY
AFTERNOON.
PRES GRADIENT WEAKENS BY TONIGHT AND CONTINUES INTO TUESDAY AS HIGH
PRES RIDGE MOVES OVER THE AREA. WINDS WILL BE GENERALLY LESS THAN 20
KT THROUGH THE PD. LIGHT WINDS WILL CONTINUE TUE NIGHT INTO WED
MORNING AS A LOW PRES TROUGH MOVES INTO THE AREA...BUT THEN WINDS
RAMP UP ON THE BACKSIDE OF THE TROUGH WITH NORTH GALES TO 35 KNOTS
EXPECTED ACROSS MUCH OF THE LAKE WED NIGHT. NORTH WINDS SHOULD COME
DOWN BLO GALES ON THU BUT WILL REMAIN UP TO 30 KNOTS OVER THE EAST
HALF.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST /NOON CST/ THIS
AFTERNOON FOR LSZ162-263-264-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...SRF
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
419 AM EST SUN FEB 8 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 418 AM EST SUN FEB 8 2015
IT APPEARS THAT MUCH OF THE FREEZING DRIZZLE FROM LAST EVENING/EARLY
OVERNIGHT HAS TURNED OVER TO LIGHT -SHSN OR FLURRIES ACROSS MUCH OF
THE CWA AS TEMPS HAVE COOLED BLO -10C IN THE LOWEST 2KFT OF THE
AIRMASS PER RAP SOUNDINGS. IF THERE IS ANY REMAINING -FZDZ OVER SE
SECTIONS IT SHOULD BE GONE BY SUNRISE WITH THE COOLER TEMPS ALLOWING
FOR ICE CRYSTAL FORMATION IN THE CONVECTIVE LAYER.
NE FLOW AND TEMPS TO NEAR -15C WITHIN THE LOWEST 3KFT OF ATMOSPHERE
WILL FAVOR 4 WRN COUNTIES AND WRN MQT-BARAGA COUNTIES FOR LIGHT LES
TODAY. LIMITING FACTOR BESIDES FAIRLY MARGINAL INSTABILITY WILL BE
INVERSION WITHIN LOWEST 3KFT SO NOT EXPECTING MUCH IN THE WAY OF
ACCUMULATION WITH A DUSTING TO MAYBE AN INCH FOR AREAS BEST AIDED BY
UPSLOPE NE FLOW. MAX TEMPS TODAY WILL GENERALLY RANGE FROM THE TEENS
NORTH TO LOWER 20S ALONG THE WI BORDER.
WITH SHORTWAVE RIDGE AND SFC RIDGE MOVING OVERHEAD...EXPECT
SIGNIFICANT DRYING/SUBSIDENCE ALOFT TONIGHT. NAM SNDGS SHOW MOISTURE
SHALLOWING OUT BLO LOWEST 2KFT FM SFC...BUT WITH TEMP AT INVERSION
BASE OF -13 TO -14C...THERE WILL LIKELY BE SOME LIGHT LES/FLURRIES
OFF THE LAKE...ESPECIALLY FOR UPSLOPE NE TO N FLOW AREAS. STILL
WOULDN/T EXPECT ACCUMULATION ANY MORE THAN HALF AN INCH. WITH LIGHT
ERLY FLOW SETTING UP OVER FAR ERN COUNTIES THERE COULD BE SOME
CLEARING TO ALLOW TEMPS TO FALL FM 5 TO 10 BELOW ZERO AT SOME OF
TYPICAL COLD SPOTS. OVER THE WEST HALF AND SOUTH CENTRAL...TEMPS
WILL RANGE FROM THE SINGLE DIGITS ABV ZERO INLAND TO 10F OR HIGHER
NEAR THE GREAT LAKES SHORELINES.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 401 AM EST SUN FEB 8 2015
MUCH OF THE FOCUS DURING THE LONG TERM FORECAST WILL BE WITH THE
LOW PRESSURE SYSTEM MOVING EAST THROUGH THE GREAT LAKES REGION
TUESDAY NIGHT AND THEN THE COLD AIR SURGING SOUTH INTO THE AREA AND
LEADING TO ANOTHER PERIOD OF MODERATE LAKE EFFECT SNOW WEDNESDAY
AFTERNOON INTO THURSDAY MORNING.
BEFORE THE ACTIVE WEATHER DURING THE MIDDLE OF THE WEEK...THE AREA
WILL BE UNDER A WEAK SURFACE RIDGE THAT WILL BE MOVING ACROSS THE
UPPER GREAT LAKES MONDAY AND MONDAY NIGHT FROM A HIGH SLIDING OUT
OF CENTRAL CANADA AND ACROSS NORTHERN ONTARIO. LIGHT NORTHERLY FLOW
BELOW THE SUBSIDENCE INVERSION AROUND 3-4KFT WILL KEEP LOW CLOUDS
DRIFTING SOUTH ACROSS MUCH OF THE AREA MONDAY AND POSSIBLE INTO
MONDAY NIGHT. WITH 925-900MB TEMPS AROUND -12C...THERE WILL LIKELY
BE ENOUGH SUPPORT FOR A FEW LIGHT SNOW SHOWERS OR FLURRIES...BUT
THINK THE LIMITED CLOUD DEPTH WILL LIMIT BOTH COVERAGE AND
INTENSITY. AS WINDS WEAKEN HEADING INTO MONDAY NIGHT...DRIER AIR
APPEARS TO START WORKING INTO THE AREA AND SHOULD AT LEAST BREAK UP
SOME OF THE CLOUDS AWAY FROM THE LAKE/TERRAIN INFLUENCES OVER THE
NORTHERN PART OF THE CWA. HAVE CONTINUED THE DOWNWARD TREND IN POPS
THROUGH THE NIGHT...BUT DID LIKE THE IDEA SHOWN BY THE PREVIOUS
SHIFT TO HAVE SOME SLIGHT CHANCES WORK BACK INTO THE NORTH CENTRAL
TUESDAY MORNING...AS ANOTHER POCKET OF LOW LEVEL MOISTURE ROTATES
INTO THE AREA AND WINDS SHIFT BACK TO A FAVORABLE UPSLOPE NORTHEAST
WIND.
FOCUS THEN TURNS TO THE SHORTWAVE TROUGH THAT WILL COME ONSHORE
OVER THE PACIFIC NORTHWEST LATE TONIGHT AND MONDAY. THE SHORTWAVE
WILL SLIDE EAST THROUGH THE NORTHERN PLAINS ON TUESDAY AND
REDEVELOP A WEAK SURFACE LOW IN THE PLAINS. AS THESE FEATURES SHIFT
EAST ACROSS THE AREA TUESDAY NIGHT...AN INITIAL PUSH OF
PRECIPITATION WILL SHIFT ACROSS THE UPPER GREAT LAKES REGION (AIDED
BY MID LEVEL WARM AIR ADVECTION). OVERALL...MODELS IN DECENT
AGREEMENT WITH THE TIMING OF THE FORCING (ARRIVING LATE TUESDAY
AFTERNOON AND PUSHING THROUGH LARGELY DURING THE EVENING AND EARLY
OVERNIGHT HOURS. WILL FOLLOW THAT FOR TIMING OF THE PRECIPITATION
AND CONTINUE TO SHOW A PERIOD OF LIKELY VALUES FOR TUESDAY NIGHT.
ALTHOUGH THERE ARE SLIGHT DIFFERENCES IN THE QPF FIELDS (DUE TO THE
DIFFERENCES IN THE EMBEDDED PIECES OF ENERGY AND WHETHER THEY STAY
SOUTH OF OR MOVE THROUGH THE CWA)...IT APPEARS MUCH OF THE CWA WILL
SEE BETWEEN 0.1-0.2 INCH OF QPF. WILL NEED TO WATCH THE THERMAL
PROFILE...AS MUCH OF THE FORCING RIGHT NOW IS ON THE EDGE OF THE
DGZ AND HIGHER SNOW RATIOS. WILL FOLLOW A GENERAL 13-15 TO 1 FOR
NOW...WHICH WOULD LEAD TO 1-3.5 INCHES OF SNOWFALL THROUGH TUESDAY
NIGHT.
EXPECT A BRIEF PERIOD LULL IN THE PRECIPITATION LATE TUESDAY NIGHT
AND WEDNESDAY MORNING BEFORE THE COLD AIR SURGES INTO THE AREA
UNDER INCREASING NORTHWESTERLY WINDS AS A STRONG NORTHERN STREAM
SHORTWAVE DIVES SOUTHEAST ACROSS THE AREA. THIS WILL USHER IN
SIGNIFICANTLY COLDER AIR...850MB TEMPS FALLING FROM -10C TUESDAY
NIGHT TO -22C WEDNESDAY NIGHT...AND LEAD TO THE DEVELOPMENT OF LAKE
EFFECT. WITH THE ADDITIONAL MOISTURE AND STEEPENING LOW LEVEL LAPSE
RATES (LAKE EQUILIBRIUM LEVELS RISING TO AROUND 8KFT) ASSOCIATED
WITH THE SHORTWAVE AND COLDER AIR MOVING INTO THE AREA...EXPECT A
PERIOD OF MODERATE LAKE EFFECT SNOW LATE WEDNESDAY AFTERNOON AND
INTO WEDNESDAY NIGHT. WHILE IT WILL INITIALLY BE IN THE NORTHWEST
WIND SNOWBELTS...QUICKLY VEERING WINDS TO THE NORTH WEDNESDAY
EVENING WILL FOCUS THE SNOW IN THOSE FAVORED AREAS. WILL FOCUS THE
HIGHEST POPS/SNOWFALL OVER THE NORTH CENTRAL (AND NORTHERN PARTS
OF THE KEWEENAW PENINSULA) WHERE THE LONGEST ICE FREE FETCH
IS LOCATED...WITH LESSER AMOUNTS OVER THE WESTERN AREAS DUE TO THE
ICE AROUND ISLE ROYALE SHORTING THE FETCH. WHILE MUCH OF THE
FORCING WILL BE IN THE DGZ DURING THIS FAVORABLE PERIOD OF LAKE
EFFECT...THINK THE STRONG WINDS (25-35KTS) WILL FRACTURE THE FLAKES
AND LIMIT THE ACCUMULATIONS SOME. BUT THIS WILL LEAD TO INCREASED
VISIBILITY REDUCTION AND WILL CONTINUE THAT HEIGHTENED WORDING IN
THE HWO. EXPECT THE SNOW INTENSITY TO QUICKLY DIMINISH FROM WEST TO
EAST ON THURSDAY...AS AN APPROACHING HIGH PRESSURE RIDGE FROM
CENTRAL CANADA LOWERS INVERSION HEIGHTS AND BRINGS DRIER AIR INTO
THE AREA. WITH THE COLD AIR IN PLACE ON THURSDAY (HIGHS IN THE
SINGLE DIGITS AND LOWER TEENS ABOVE ZERO)...THURSDAY NIGHT LOOKS TO
BE A COLD NIGHT WHERE SKIES CLEAR OUT AWAY FROM ANY LINGERING LAKE
EFFECT. THEREFORE...HAVE TRENDED LOWS DOWN SEVERAL DEGREES OVER THE
INTERIOR WEST (INTO THE TEENS BELOW ZERO) AND COULD SEE TEMPS NEAR
WHAT OCCURRED A FEW MORNINGS AGO (-20S IN THE COLD SPOTS) IF THE
HIGH CLOUDS FROM THE NEXT SHORTWAVE HOLD OFF LONG ENOUGH.
THE AREA OF HIGH PRESSURE WILL SLIDE SOUTHEAST OF THE AREA ON
FRIDAY...AS ANOTHER SHORTWAVE DIVES SOUTHEAST ACROSS THE AREA
THAT AFTERNOON. EXPECT ANY SNOWFALL AMOUNTS TO BE LIGHT DUE TO
THE LIMITED MOISTURE AVAILABLE...BUT IT WILL USHER IN ANOTHER
PERIOD OF LAKE EFFECT SNOW FOR LATER FRIDAY NIGHT AND SATURDAY.
LOOKING FARTHER OUT INTO THE FUTURE...LOOKS LIKE LITTLE CHANGE TO
THE OVERALL PATTERN (RIDGE OVER THE WEST AND TROUGH OVER EASTERN
CANADA) SO THE BELOW NORMAL TEMPERATURES LOOK TO CONTINUE INTO NEXT
WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1238 AM EST SUN FEB 8 2015
FREEZING DRIZZLE WILL BE DOMINANT PTYPE AT THE TAF SITES MOST OF THE
OVERNIGHT BEFORE SWITCHING BACK TO LGT SNOW OR FLURRIES TOWARD
MORNING. EXPECT MAINLY MVFR CONDITIONS AT KIWD AND IFR CONDITIONS AT
KCMX. THE IFR CONDITIONS WILL SLOWLY EASE AT KSAW AS THE NIGHT WEARS
ON. FOR THE DAYTIME ON SUNDAY...EXPECT LAKE EFFECT SNOW TO AFFECT
ALL THE TAF SITES AT TIME...ESPECIALLY AT KCMX AS THE EASTERLY
UPSLOPE FLOW PERSISTS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 418 AM EST SUN FEB 8 2015
TIGHT PRES GRADIENT AND NE WINDS CHANNELING DOWN THE WRN HALF OF THE
LAKE WILL RESULT IN SOLID WINDS TO 30 KT WITH A FEW SPOTS SEEING
GALE FORCE GUSTS THIS MORNING. HIGH WINDS WILL ALSO RESULT IN HEAVY
FREEZING SPRAY FOR WEST AND CENTRAL LAKE SUPERIOR INTO EARLY
AFTERNOON.
PRES GRADIENT WEAKENS BY TONIGHT AND CONTINUES INTO TUESDAY AS HIGH
PRES RIDGE MOVES OVER THE AREA. WINDS WILL BE GENERALLY LESS THAN 20
KT THROUGH THE PD. LIGHT WINDS WILL CONTINUE TUE NIGHT INTO WED
MORNING AS A LOW PRES TROUGH MOVES INTO THE AREA...BUT THEN WINDS
RAMP UP ON THE BACKSIDE OF THE TROUGH WITH NORTH GALES TO 35 KNOTS
EXPECTED ACROSS MUCH OF THE LAKE WED NIGHT. NORTH WINDS SHOULD COME
DOWN BLO GALES ON THU BUT WILL REMAIN UP TO 30 KNOTS OVER THE EAST
HALF.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST /NOON CST/ THIS
AFTERNOON FOR LSZ162-263-264-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...SRF
AVIATION...JLA
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
416 AM EST SUN FEB 8 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 416 AM EST SUN FEB 8 2015
IT APPEARS THAT MUCH OF THE FREEZING DRIZZLE FROM LAST EVENING/EARLY
OVERNIGHT HAS TURNED OVER TO LIGHT -SHSN OR FLURRIES ACROSS MUCH OF
THE CWA AS TEMPS HAVE COOLED BLO -10C IN THE LOWEST 2KFT OF THE
AIRMASS PER RAP SOUNDINGS. IF THERE IS ANY REMAINING -FZDZ OVER SE
SECTIONS IT SHOULD BE GONE BY SUNRISE WITH THE COOLER TEMPS ALLOWING
FOR ICE CRYSTAL FORMATION IN THE CONVECTIVE LAYER.
NE FLOW AND TEMPS TO NEAR -15C WITHIN THE LOWEST 3KFT OF ATMOSPHERE
WILL FAVOR 4 WRN COUNTIES AND WRN MQT-BARAGA COUNTIES FOR LIGHT LES
TODAY. LIMITING FACTOR BESIDES FAIRLY MARGINALLY INSTABILITY WILL BE
INVERSION WITHIN LOWEST 3KFT SO NOT EXPECTING MUCH IN THE WAY OF
ACCUMULATION WITH A DUSTING TO MAYBE AN INCH FOR AREAS BEST AIDED BY
UPSLOPE NE FLOW. MAX TEMPS TODAY WILL GENERALLY RANGE FROM THE
TEENS NORTH TO LOWER 20S ALONG THE WI BORDER.
WITH SHORTWAVE RIDGE AND SFC RIDGE MOVING OVERHEAD...EXPECT
SIGNIFICANT DRYING/SUBSIDENCE ALOFT TONIGHT. NAM SNDGS SHOW MOISTURE
SHALLOWING OUT BLO LOWEST 2KFT FM SFC...BUT WITH TEMP AT INVERSION
BASE OF -13 TO -14C...THERE WILL LIKELY BE SOME LIGHT LES/FLURRIES
OFF THE LAKE...ESPECIALLY FOR UPSLOPE NE TO N FLOW AREAS. STILL
WOULDN/T EXPECT ACCUMULATION ANY MORE THAN HALF AN INCH. WITH LIGHT
ERLY FLOW SETTING UP OVER FAR ERN COUNTIES THERE COULD BE SOME
CLEARING TO ALLOW TEMPS TO FALL FM 5 TO 10 BELOW ZERO AT SOME OF
TYPICAL COLD SPOTS. OVER THE WEST HALF AND SOUTH CENTRAL...TEMPS
WILL RANGE FROM THE SINGLE DIGITS ABV ZERO INLAND TO 10F OR HIGHER
NEAR THE GREAT LAKES SHORELINES.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 401 AM EST SUN FEB 8 2015
MUCH OF THE FOCUS DURING THE LONG TERM FORECAST WILL BE WITH THE
LOW PRESSURE SYSTEM MOVING EAST THROUGH THE GREAT LAKES REGION
TUESDAY NIGHT AND THEN THE COLD AIR SURGING SOUTH INTO THE AREA AND
LEADING TO ANOTHER PERIOD OF MODERATE LAKE EFFECT SNOW WEDNESDAY
AFTERNOON INTO THURSDAY MORNING.
BEFORE THE ACTIVE WEATHER DURING THE MIDDLE OF THE WEEK...THE AREA
WILL BE UNDER A WEAK SURFACE RIDGE THAT WILL BE MOVING ACROSS THE
UPPER GREAT LAKES MONDAY AND MONDAY NIGHT FROM A HIGH SLIDING OUT
OF CENTRAL CANADA AND ACROSS NORTHERN ONTARIO. LIGHT NORTHERLY FLOW
BELOW THE SUBSIDENCE INVERSION AROUND 3-4KFT WILL KEEP LOW CLOUDS
DRIFTING SOUTH ACROSS MUCH OF THE AREA MONDAY AND POSSIBLE INTO
MONDAY NIGHT. WITH 925-900MB TEMPS AROUND -12C...THERE WILL LIKELY
BE ENOUGH SUPPORT FOR A FEW LIGHT SNOW SHOWERS OR FLURRIES...BUT
THINK THE LIMITED CLOUD DEPTH WILL LIMIT BOTH COVERAGE AND
INTENSITY. AS WINDS WEAKEN HEADING INTO MONDAY NIGHT...DRIER AIR
APPEARS TO START WORKING INTO THE AREA AND SHOULD AT LEAST BREAK UP
SOME OF THE CLOUDS AWAY FROM THE LAKE/TERRAIN INFLUENCES OVER THE
NORTHERN PART OF THE CWA. HAVE CONTINUED THE DOWNWARD TREND IN POPS
THROUGH THE NIGHT...BUT DID LIKE THE IDEA SHOWN BY THE PREVIOUS
SHIFT TO HAVE SOME SLIGHT CHANCES WORK BACK INTO THE NORTH CENTRAL
TUESDAY MORNING...AS ANOTHER POCKET OF LOW LEVEL MOISTURE ROTATES
INTO THE AREA AND WINDS SHIFT BACK TO A FAVORABLE UPSLOPE NORTHEAST
WIND.
FOCUS THEN TURNS TO THE SHORTWAVE TROUGH THAT WILL COME ONSHORE
OVER THE PACIFIC NORTHWEST LATE TONIGHT AND MONDAY. THE SHORTWAVE
WILL SLIDE EAST THROUGH THE NORTHERN PLAINS ON TUESDAY AND
REDEVELOP A WEAK SURFACE LOW IN THE PLAINS. AS THESE FEATURES SHIFT
EAST ACROSS THE AREA TUESDAY NIGHT...AN INITIAL PUSH OF
PRECIPITATION WILL SHIFT ACROSS THE UPPER GREAT LAKES REGION (AIDED
BY MID LEVEL WARM AIR ADVECTION). OVERALL...MODELS IN DECENT
AGREEMENT WITH THE TIMING OF THE FORCING (ARRIVING LATE TUESDAY
AFTERNOON AND PUSHING THROUGH LARGELY DURING THE EVENING AND EARLY
OVERNIGHT HOURS. WILL FOLLOW THAT FOR TIMING OF THE PRECIPITATION
AND CONTINUE TO SHOW A PERIOD OF LIKELY VALUES FOR TUESDAY NIGHT.
ALTHOUGH THERE ARE SLIGHT DIFFERENCES IN THE QPF FIELDS (DUE TO THE
DIFFERENCES IN THE EMBEDDED PIECES OF ENERGY AND WHETHER THEY STAY
SOUTH OF OR MOVE THROUGH THE CWA)...IT APPEARS MUCH OF THE CWA WILL
SEE BETWEEN 0.1-0.2 INCH OF QPF. WILL NEED TO WATCH THE THERMAL
PROFILE...AS MUCH OF THE FORCING RIGHT NOW IS ON THE EDGE OF THE
DGZ AND HIGHER SNOW RATIOS. WILL FOLLOW A GENERAL 13-15 TO 1 FOR
NOW...WHICH WOULD LEAD TO 1-3.5 INCHES OF SNOWFALL THROUGH TUESDAY
NIGHT.
EXPECT A BRIEF PERIOD LULL IN THE PRECIPITATION LATE TUESDAY NIGHT
AND WEDNESDAY MORNING BEFORE THE COLD AIR SURGES INTO THE AREA
UNDER INCREASING NORTHWESTERLY WINDS AS A STRONG NORTHERN STREAM
SHORTWAVE DIVES SOUTHEAST ACROSS THE AREA. THIS WILL USHER IN
SIGNIFICANTLY COLDER AIR...850MB TEMPS FALLING FROM -10C TUESDAY
NIGHT TO -22C WEDNESDAY NIGHT...AND LEAD TO THE DEVELOPMENT OF LAKE
EFFECT. WITH THE ADDITIONAL MOISTURE AND STEEPENING LOW LEVEL LAPSE
RATES (LAKE EQUILIBRIUM LEVELS RISING TO AROUND 8KFT) ASSOCIATED
WITH THE SHORTWAVE AND COLDER AIR MOVING INTO THE AREA...EXPECT A
PERIOD OF MODERATE LAKE EFFECT SNOW LATE WEDNESDAY AFTERNOON AND
INTO WEDNESDAY NIGHT. WHILE IT WILL INITIALLY BE IN THE NORTHWEST
WIND SNOWBELTS...QUICKLY VEERING WINDS TO THE NORTH WEDNESDAY
EVENING WILL FOCUS THE SNOW IN THOSE FAVORED AREAS. WILL FOCUS THE
HIGHEST POPS/SNOWFALL OVER THE NORTH CENTRAL (AND NORTHERN PARTS
OF THE KEWEENAW PENINSULA) WHERE THE LONGEST ICE FREE FETCH
IS LOCATED...WITH LESSER AMOUNTS OVER THE WESTERN AREAS DUE TO THE
ICE AROUND ISLE ROYALE SHORTING THE FETCH. WHILE MUCH OF THE
FORCING WILL BE IN THE DGZ DURING THIS FAVORABLE PERIOD OF LAKE
EFFECT...THINK THE STRONG WINDS (25-35KTS) WILL FRACTURE THE FLAKES
AND LIMIT THE ACCUMULATIONS SOME. BUT THIS WILL LEAD TO INCREASED
VISIBILITY REDUCTION AND WILL CONTINUE THAT HEIGHTENED WORDING IN
THE HWO. EXPECT THE SNOW INTENSITY TO QUICKLY DIMINISH FROM WEST TO
EAST ON THURSDAY...AS AN APPROACHING HIGH PRESSURE RIDGE FROM
CENTRAL CANADA LOWERS INVERSION HEIGHTS AND BRINGS DRIER AIR INTO
THE AREA. WITH THE COLD AIR IN PLACE ON THURSDAY (HIGHS IN THE
SINGLE DIGITS AND LOWER TEENS ABOVE ZERO)...THURSDAY NIGHT LOOKS TO
BE A COLD NIGHT WHERE SKIES CLEAR OUT AWAY FROM ANY LINGERING LAKE
EFFECT. THEREFORE...HAVE TRENDED LOWS DOWN SEVERAL DEGREES OVER THE
INTERIOR WEST (INTO THE TEENS BELOW ZERO) AND COULD SEE TEMPS NEAR
WHAT OCCURRED A FEW MORNINGS AGO (-20S IN THE COLD SPOTS) IF THE
HIGH CLOUDS FROM THE NEXT SHORTWAVE HOLD OFF LONG ENOUGH.
THE AREA OF HIGH PRESSURE WILL SLIDE SOUTHEAST OF THE AREA ON
FRIDAY...AS ANOTHER SHORTWAVE DIVES SOUTHEAST ACROSS THE AREA
THAT AFTERNOON. EXPECT ANY SNOWFALL AMOUNTS TO BE LIGHT DUE TO
THE LIMITED MOISTURE AVAILABLE...BUT IT WILL USHER IN ANOTHER
PERIOD OF LAKE EFFECT SNOW FOR LATER FRIDAY NIGHT AND SATURDAY.
LOOKING FARTHER OUT INTO THE FUTURE...LOOKS LIKE LITTLE CHANGE TO
THE OVERALL PATTERN (RIDGE OVER THE WEST AND TROUGH OVER EASTERN
CANADA) SO THE BELOW NORMAL TEMPERATURES LOOK TO CONTINUE INTO NEXT
WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1238 AM EST SUN FEB 8 2015
FREEZING DRIZZLE WILL BE DOMINANT PTYPE AT THE TAF SITES MOST OF THE
OVERNIGHT BEFORE SWITCHING BACK TO LGT SNOW OR FLURRIES TOWARD
MORNING. EXPECT MAINLY MVFR CONDITIONS AT KIWD AND IFR CONDITIONS AT
KCMX. THE IFR CONDITIONS WILL SLOWLY EASE AT KSAW AS THE NIGHT WEARS
ON. FOR THE DAYTIME ON SUNDAY...EXPECT LAKE EFFECT SNOW TO AFFECT
ALL THE TAF SITES AT TIME...ESPECIALLY AT KCMX AS THE EASTERLY
UPSLOPE FLOW PERSISTS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 416 AM EST SUN FEB 8 2015
TIGHT PRES GRADIENT AND NE WINDS CHANNELING DOWN THE WRN HALF OF THE
LAKE WILL RESULT IN SOLID WINDS TO 30 KT WITH A FEW SPOTS SEEING
GALE FORCE GUSTS THIS MORNING. HIGH WINDS WILL ALSO RESULT IN HEAVY
FREEZING SPRAY FOR WEST AND CENTRAL LAKE SUPERIOR INTO EARLY
AFTERNOON.
PRES GRADIENT WEAKENS BY TONIGHT AND CONTINUES INTO TUESDAY AS HIGH
PRES RIDGE MOVES OVER THE AREA. WINDS WILL BE GENERALLY LESS THAN 20
KT THROUGH THE PD. LIGHT WINDS WILL CONTINUE TUE NIGHT INTO WED
MORNING AS A LOW PRES TROUGH MOVES INTO THE AREA...BUT THEN WINDS
RAMP UP ON THE BACKSIDE OF THE TROUGH WITH NORTH GALES TO 35 KNOTS
EXPECTED ACROSS MUCH OF THE LAKE WED NIGHT. NORTH WINDS SHOULD COME
DOWN BLO GALES ON THU BUT WILL REMAIN UP TO 30 KNOTS OVER THE EAST
HALF.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST /NOON CST/ THIS
AFTERNOON FOR LSZ162-263-264-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...SRF
AVIATION...JLA
MARINE...VOSS
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
959 PM CST MON FEB 9 2015
.UPDATE...
ISSUED AT 959 PM CST MON FEB 9 2015
AFTER WATCHING SEVERAL RUNS OF THE RAP...HRRR...AND HOPWRF DECIDED
TO EXPAND THE ADVISORY SLIGHTLY SOUTH AND EAST TO ENCOMPASS THE
ENTIRE TWIN CITIES METRO AND THE REST OF WEST CENTRAL WISCONSIN.
NOT MUCH ON RADAR OUT TO THE WEST LATE THIS EVENING...BUT
STRENGTHENING WAA OVERNIGHT WILL ALLOW PRECIP TO BLOSSOM ACROSS
THE EASTERN DAKOTAS AFTER 06-08Z. THIS WAA WILL MAXIMIZE AROUND
12Z ACROSS WRN MN...15Z ACROSS ERN MN...AND 18Z OVER WRN WI. A
DEEP MOIST LAYER AND HIGH DGZ CENTERED AROUND 550 MB ALLOWS FOR
NOT ONLY A HIGH MOISTURE CONTENT ATMOSPHERE WITH PW VALUES ABOVE
0.6 INCHES /NEARING 3 STANDARD DEVIATIONS ABOVE AVERAGE/...BUT
ALSO SOME CAPE FROM THE DGZ UPWARD AND THUS CONVECTIVE POTENTIAL.
THE STRONG FORCING WITH THIS BAND COUPLED WITH THE MOISTURE
CONTENT AND WEAK INSTABILITY ALOFT SHOULD ALLOW THE INITIAL BAND
OF PRECIP TO BECOME PRETTY INTENSE FOR A TIME. RAPIDLYDETERIORATING
CONDITIONS ARE THUS EXPECTED SHORTLY AFTER THE ONSET. FOR SEVERAL
RUNS...THE RAP HAS HINTED AT 1-2 INCH PER HOUR RATES AS THE BAND
PUSHES INTO ERN MN AND WRN WI AND THIS SEEMS REASONABLE.
IF THIS WERE TO PERSIST FOR MORE THAN A COUPLE HOURS...COULD
PROBABLY JUSTIFY A WARNING. HOWEVER...THERE ARE SOME
SIGNS...PARTICULARLY ACROSS WRN AND SRN MN...THAT ONCE THIS BAND
GOES THROUGH THAT MAY BE IT FOR STEADY PRECIP AS DRY SLOTTING
COMES IN.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 413 PM CST MON FEB 9 2015
TURNED OUT TO BE A BEAUTIFUL DAY OUTSIDE OF WESTERN AND FAR SOUTHERN
MN...AS A WEDGE OF DRY AIR EMANATING FROM HIGH PRESSURE MOVING INTO
WRN ONTARIO HELPED CLEAR SKIES OUT. HOWEVER...TROUBLE IS ALREADY
BREWING TO OUR WEST AS WATER VAPOR IMAGERY SHOWS A POWERFUL WAVE
MOVING ACROSS THE NW CONUS. THIS WAVE WILL QUICKLY WORK ACROSS THE
DAKOTAS TONIGHT AND MN TUESDAY...PROVIDING US WITH THE POTPOURRI OF
WINTRY PRECIPITATION ON TUESDAY THAT WE HAVE BEEN ADVERTISING FOR
THE LAST SEVERAL DAYS.
WE DID NOT SEE MUCH CHANGE IN THE GUIDANCE TODAY WITH WHAT WAS SEEN
LAST NIGHT...SO THIS FORECAST DID NOT CHANGE A WHOLE LOT
EITHER...WITH ABOUT THE ONLY CHANGE OF SIGNIFICANCE BEING TO SLOW
DOWN HOW QUICKLY PRECIP MOVES INTO AND THEN ACROSS THE MPX CWA.
THIS FORECAST FAVORED THE GFS FOR BOTH P-TYPE AND QPF. FOR P-
TYPE...THE NAM...ALONG WITH THE RAP WERE CONSIDERABLY WARMER WITH
THE WARM NOSE ALOFT THAN THE GFS/ECMWF. HAD WE GONE THE NAM
ROUTE...A MIX WOULD HAVE BEEN MENTIONED FARTHER NORTH THAN IT IS
TUESDAY AFTERNOON...AND SAID MIX WOULD BE MORE OF A FZRA/SLEET/SNOW
MIX /MOST LIKELY TO LEAST LIKELY/ AS OPPOSED TO THE CURRENT
SLEET/SNOW/FZRA MIX THAT WE HAVE.
FOR QPF...THE NAM IS A CONSIDERABLE SRN OUTLIER. THE POTENTIAL
PROBLEM WITH IT STARTS TONIGHT...WHEN THE NAM SHOWS NEARLY A QUARTER
INCH OF QPF FALLING BY 12Z TUESDAY IN NE SODAK...IN ADDITION TO
ANOTHER QPF BULLSEYE FROM CENTRAL NODAK INTO SE NODAK. THE RAP AND
HOPWRF HAVE THE NODAK BULLSEYE...BUT SHOW CONSIDERABLY LESS QPF INTO
SODAK. THE LATENT HEAT DIFFERENCES THIS CREATES THEN CASCADES INTO
TUESDAY...WHEN THE NAM SHOWS QPF IN EXCESS OF 0.3" ALL THE WAY DOWN
TO MANKATO. THE GFS ON THE OTHER HAND HAS THE NODAK QPF...BUT MUCH
LOWER QPF DOWN INTO SODAK...SIMILAR TO WHAT THE RAP/HOPWRF
HAVE...HENCE FAVORING THE QPF THAT DIRECTION. WE THEN TEMPERED THE
GFS QPF A BIT WITH THE ECMWF/SREF AND ENDED UP WITH 0.3" QPF DOWN
ABOUT AS FAR SOUTH AS THE TWIN CITIES DOWN TO MENOMONIE.
CONVERTING THIS QPF OVER TO SNOW WITH RATIOS IN THE 10-12:1 RANGE
AND WE ENDED UP WITH SNOWFALL AMOUNTS BETWEEN 2 AND 5 INCHES NORTH
OF A MORRIS/MINNEAPOLIS/EAU CLAIRE LINE WITH THE LARGEST AMOUNTS
UP AROUND MILLE LACS LAKE TO POINTS EAST.
THE HEAVIEST SNOW IS EXPECTED IN CENTRAL MN AS THEY WILL GET THE
COMBINATION OF WAA AND DEFORMATION SNOW. FARTHER SOUTH...THE
MAJORITY OF THE PRECIP WILL FALL IN THE WAA BAND. THIS WILL RESULT
IN A 2-4 HOUR WINDOW WHERE SNOWFALL RATES ARE LIKELY NEAR OR IN
EXCESS OF AN INCH PER HOUR...SO THIS SNOW WILL FALL IN A SHORT
AMOUNT OF TIME. TIMING WISE...THINGS DO NOT LOOK TO BE TO DISSIMILAR
FROM WHAT WE SAW LAST TUESDAY WHEN ABOUT 2 INCHES OF SNOW SEVERAL
IMPACTED THE EVENING COMMUTE IN THE TWIN CITIES. WITH A SIMILAR
SCENARIO EXPECTED TO TO PLAY OUT TOMORROW...PULLED THE ADVISORY DOWN
TO COVER ALL BUT THE SRN TWIN CITIES METRO. DECIDED AGAINST PUTTING
HEADLINES ANY FARTHER SOUTH THAN WHAT WE HAVE NOW SINCE THERE ARE
MORE QUESTIONS AS TO HOW MUCH PRECIP LOCATIONS FARTHER SOUTH WILL
ACTUALLY SEE. IN ADDITION...WITH CURRENT PRIMARY P-TYPE EXPECTED TO
BE SLEET AS OPPOSED TO FREEZING RAIN...THAT WILL LIMIT THE TRAVEL
IMPACT FROM THIS PRECIP AS WELL. HOWEVER...THIS WILL BE AN AREA THAT
WILL NEED TO BE CLOSELY MONITORED THROUGH THE NIGHT.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 413 PM CST MON FEB 9 2015
THE EXTENDED PERIOD CAN BE CHARACTERIZED AS BLW NORMAL IN TERMS OF
TEMPERATURES AS THE MEAN PATTERN SHIFTS TO A MORE NW
DIRECTION...LEADING TO COLDER CANADIAN AIR FILTERING SOUTHWARD.
A BRIEF PERIOD TUESDAY EVENING OF MIXED PRECIPITATION ALONG THE MN
RIVER VALLEY WILL QUICKLY CHG TO ALL SNOW AS A MUCH COLDER AIR MASS
REPLACES THE CURRENT ONE. BASED ON THE STRENGTH OF A SECONDARY
SHRTWV MOVING SE ACROSS THE UPPER MIDWEST TUESDAY NIGHT/WEDNESDAY
AND THE STRENGTH OF THE CAA BEHIND IT...BREEZY/WINDY CONDS WILL
DEVELOP...ESPECIALLY IN THE TYPICAL AREAS OF WC/SC MN WHERE GUSTS UP
TO 45 MPH WILL BE COMMON. WAS CONSIDERING A BLOWING SNOW PROBLEM IN
THESE AREAS...BUT DO TO A LACK OF SNOW COVER AND NO ADDITIONAL NEW
SNOW EXPECTED...DO NOT ANTICIPATE ANY CONCERNS.
VERY LITTLE CHC/S OF PRECIPITATION IS EXPECTED PAST TUESDAY
EVENING...WITH THE EXCEPTION BY NEXT MONDAY AS THE MEAN PATTERN WILL
REMAIN DRY AND UNEVENTFUL. TWO STRONG COLD FRONTS WILL MOVE ACROSS
OUR REGION...ONE WILL OCCUR TUESDAY AFTN/EVENING...AND ANOTHER
FRIDAY AFTN/SATURDAY MORNING. THESE FRONTS WILL CAUSE A FEW SNOW
SHOWERS TO DEVELOP...BUT AGAIN NOT EXPECTING MUCH IN THE WAY OF
ACCUMULATIONS.
OVER THE PAST TWO MONTHS...THE MEAN AREA OF ARCTIC AIR HAS REMAINED
ACROSS NE NORTH AMERICA...AFFECTING MAINLY THE NE CONUS...AND
EASTERN CANADA. ONCE IN A WHILE A BRIEF COLD SPELL MOVES ACROSS THE
UPPER MIDWEST/GREAT LAKES AS THE PATTERN BUCKLES. THE LATEST
PROBABILISTIC FORECASTS ON NCEP GEFS REFORECASTS CFS/V2...HAS 50H
ANOMALIES SHIFTING ACROSS THE ALASKA REGION...WITH A SECONDARY 50H
ANOMALY FOCUSING ACROSS THE DEEP SOUTH/SW. THIS BASICALLY SHIFTS THE
COLDER AIR ACROSS NORTHEAST CANADA FURTHER TO THE SW ACROSS THE
GREAT LAKES...AND THE EASTERN 1/3 OF NORTH AMERICA. THIS ALSO
SUGGESTS A STRONGER CORRELATION OF ABV NORMAL ANOMALIES FOCUSING
ACROSS THE GREAT BASIN AND THE FAR WEST COAST. THE TIME FRAME FOR
THIS PERIOD IS FEB 15 TO FEB 24. THE 45 DAY CFS PLUMES FOR THE PAST
4 RUNS DOES SUPPORT THE COLDER PATTERN DEVELOPING IN OUR REGION FOR
THE SECOND AND THIRD WEEK OF FEB 24. IN ADDITION...IT SEEMS IT MAYBE
A WETTER PATTERN AS THE STRONGER JET WORKS ACROSS THE CENTRAL
CONUS...LEADING TO A BETTER CHC OF A THERMAL BOUNDARY AND WIDESPREAD
PRECIPITATION.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 636 PM CST MON FEB 9 2015
WILL BE MAINTAINING VFR CONDITIONS ACROSS ERN MN AND WRN WI
THROUGH MUCH OF THE OVERNIGHT WITH MVFR OR LOWER CIGS HOLDING
NEARLY STATIONARY ACROSS WRN AND SRN MN. EVENTUALLY MOISTURE WILL
BEGIN INCHING EASTWARD TOWARD DAYBREAK WITH DETERIORATING
CONDITIONS. SNOW AND SLEET WILL BEGIN ACROSS WRN WI AROUND
09Z...WHICH WILL SPREAD EAST IN THE FORM OF A PRIMARY BAND THAT
COULD BECOME HEAVY AS IT HEADS INTO ERN MN MID MORNING AND WRN WI
LATE MORNING/EARLY AFTERNOON. HI-RES MODELS INDICATING 1-2 INCHES
OF SNOW PER HOUR WITH THIS BAND GIVEN ITS CONVECTIVE NATURE. IT IS
POSSIBLE THE TAFS ARE TOO OPTIMISTIC DURING THIS TIME.
ALSO...THESE HI-RES MODELS SHOW THE BAND ARRIVING ABOUT 2 HOURS
EARLIER THAN CURRENTLY FORECAST SO WILL MONITOR TRENDS THIS
EVENING. IT IS UNCLEAR HOW THINGS WILL EVOLVE BEHIND THIS BAND.
ACROSS SRN MN...THAT MAY MARK THE END OF PRECIP AS DRY SLOT LIFTS
NORTH. SHOULD CONTINUE SNOWING THROUGH AFTERNOON ACROSS WRN WI AND
CENTRAL MN...BUT WILL BE OF LIGHTER NATURE THAN WITH THE INITIAL
BAND.
KMSP...VFR FOR THE NEXT 12 HOURS. KEPT THE PRECIP START TIME OF
15Z...BUT THIS MAY NEED TO BE BUMPED UP AT SOME POINT ACCORDING TO
THE LATEST GUIDANCE. ALSO...IT IS BEGINNING TO LOOK LIKE THE BEST
CHANCE FOR HEAVY SNOW ARRIVES DURING THE LATE MORNING AS OPPOSED
TO AFTERNOON. WILL CONTINUE TO MONITOR.
/OUTLOOK FOR KMSP/
WED...MVFR WITH FLURRIES POSSIBLE. WINDS NW 15G30KT.
THU...BCMG VFR. WINDS BCMG LGT/VAR.
FRI...CHC MVFR CIGS. WINDS SW 5-10 KTS BCMG NW 15-20G25 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY FROM 6 AM TO 9 PM CST TUESDAY FOR MNZ041-
042-047>049-054>058-064>067.
WINTER WEATHER ADVISORY FROM 9 AM TUESDAY TO MIDNIGHT CST
TUESDAY NIGHT FOR MNZ043>045-050>053-059>063-068>070.
WI...WINTER WEATHER ADVISORY FROM 9 AM TUESDAY TO MIDNIGHT CST
TUESDAY NIGHT FOR WIZ014-023-024.
WINTER WEATHER ADVISORY FROM NOON TUESDAY TO MIDNIGHT CST
TUESDAY NIGHT FOR WIZ015-016-025>028.
&&
$$
UPDATE...BORGHOFF
SHORT TERM...MPG
LONG TERM...JLT
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
636 PM CST MON FEB 9 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 413 PM CST MON FEB 9 2015
TURNED OUT TO BE A BEAUTIFUL DAY OUTSIDE OF WESTERN AND FAR SOUTHERN
MN...AS A WEDGE OF DRY AIR EMANATING FROM HIGH PRESSURE MOVING INTO
WRN ONTARIO HELPED CLEAR SKIES OUT. HOWEVER...TROUBLE IS ALREADY
BREWING TO OUR WEST AS WATER VAPOR IMAGERY SHOWS A POWERFUL WAVE
MOVING ACROSS THE NW CONUS. THIS WAVE WILL QUICKLY WORK ACROSS THE
DAKOTAS TONIGHT AND MN TUESDAY...PROVIDING US WITH THE POTPOURRI OF
WINTRY PRECIPITATION ON TUESDAY THAT WE HAVE BEEN ADVERTISING FOR
THE LAST SEVERAL DAYS.
WE DID NOT SEE MUCH CHANGE IN THE GUIDANCE TODAY WITH WHAT WAS SEEN
LAST NIGHT...SO THIS FORECAST DID NOT CHANGE A WHOLE LOT
EITHER...WITH ABOUT THE ONLY CHANGE OF SIGNIFICANCE BEING TO SLOW
DOWN HOW QUICKLY PRECIP MOVES INTO AND THEN ACROSS THE MPX CWA.
THIS FORECAST FAVORED THE GFS FOR BOTH P-TYPE AND QPF. FOR P-
TYPE...THE NAM...ALONG WITH THE RAP WERE CONSIDERABLY WARMER WITH
THE WARM NOSE ALOFT THAN THE GFS/ECMWF. HAD WE GONE THE NAM
ROUTE...A MIX WOULD HAVE BEEN MENTIONED FARTHER NORTH THAN IT IS
TUESDAY AFTERNOON...AND SAID MIX WOULD BE MORE OF A FZRA/SLEET/SNOW
MIX /MOST LIKELY TO LEAST LIKELY/ AS OPPOSED TO THE CURRENT
SLEET/SNOW/FZRA MIX THAT WE HAVE.
FOR QPF...THE NAM IS A CONSIDERABLE SRN OUTLIER. THE POTENTIAL
PROBLEM WITH IT STARTS TONIGHT...WHEN THE NAM SHOWS NEARLY A QUARTER
INCH OF QPF FALLING BY 12Z TUESDAY IN NE SODAK...IN ADDITION TO
ANOTHER QPF BULLSEYE FROM CENTRAL NODAK INTO SE NODAK. THE RAP AND
HOPWRF HAVE THE NODAK BULLSEYE...BUT SHOW CONSIDERABLY LESS QPF INTO
SODAK. THE LATENT HEAT DIFFERENCES THIS CREATES THEN CASCADES INTO
TUESDAY...WHEN THE NAM SHOWS QPF IN EXCESS OF 0.3" ALL THE WAY DOWN
TO MANKATO. THE GFS ON THE OTHER HAND HAS THE NODAK QPF...BUT MUCH
LOWER QPF DOWN INTO SODAK...SIMILAR TO WHAT THE RAP/HOPWRF
HAVE...HENCE FAVORING THE QPF THAT DIRECTION. WE THEN TEMPERED THE
GFS QPF A BIT WITH THE ECMWF/SREF AND ENDED UP WITH 0.3" QPF DOWN
ABOUT AS FAR SOUTH AS THE TWIN CITIES DOWN TO MENOMONIE.
CONVERTING THIS QPF OVER TO SNOW WITH RATIOS IN THE 10-12:1 RANGE
AND WE ENDED UP WITH SNOWFALL AMOUNTS BETWEEN 2 AND 5 INCHES NORTH
OF A MORRIS/MINNEAPOLIS/EAU CLAIRE LINE WITH THE LARGEST AMOUNTS
UP AROUND MILLE LACS LAKE TO POINTS EAST.
THE HEAVIEST SNOW IS EXPECTED IN CENTRAL MN AS THEY WILL GET THE
COMBINATION OF WAA AND DEFORMATION SNOW. FARTHER SOUTH...THE
MAJORITY OF THE PRECIP WILL FALL IN THE WAA BAND. THIS WILL RESULT
IN A 2-4 HOUR WINDOW WHERE SNOWFALL RATES ARE LIKELY NEAR OR IN
EXCESS OF AN INCH PER HOUR...SO THIS SNOW WILL FALL IN A SHORT
AMOUNT OF TIME. TIMING WISE...THINGS DO NOT LOOK TO BE TO DISSIMILAR
FROM WHAT WE SAW LAST TUESDAY WHEN ABOUT 2 INCHES OF SNOW SEVERAL
IMPACTED THE EVENING COMMUTE IN THE TWIN CITIES. WITH A SIMILAR
SCENARIO EXPECTED TO TO PLAY OUT TOMORROW...PULLED THE ADVISORY DOWN
TO COVER ALL BUT THE SRN TWIN CITIES METRO. DECIDED AGAINST PUTTING
HEADLINES ANY FARTHER SOUTH THAN WHAT WE HAVE NOW SINCE THERE ARE
MORE QUESTIONS AS TO HOW MUCH PRECIP LOCATIONS FARTHER SOUTH WILL
ACTUALLY SEE. IN ADDITION...WITH CURRENT PRIMARY P-TYPE EXPECTED TO
BE SLEET AS OPPOSED TO FREEZING RAIN...THAT WILL LIMIT THE TRAVEL
IMPACT FROM THIS PRECIP AS WELL. HOWEVER...THIS WILL BE AN AREA THAT
WILL NEED TO BE CLOSELY MONITORED THROUGH THE NIGHT.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 413 PM CST MON FEB 9 2015
THE EXTENDED PERIOD CAN BE CHARACTERIZED AS BLW NORMAL IN TERMS OF
TEMPERATURES AS THE MEAN PATTERN SHIFTS TO A MORE NW
DIRECTION...LEADING TO COLDER CANADIAN AIR FILTERING SOUTHWARD.
A BRIEF PERIOD TUESDAY EVENING OF MIXED PRECIPITATION ALONG THE MN
RIVER VALLEY WILL QUICKLY CHG TO ALL SNOW AS A MUCH COLDER AIR MASS
REPLACES THE CURRENT ONE. BASED ON THE STRENGTH OF A SECONDARY
SHRTWV MOVING SE ACROSS THE UPPER MIDWEST TUESDAY NIGHT/WEDNESDAY
AND THE STRENGTH OF THE CAA BEHIND IT...BREEZY/WINDY CONDS WILL
DEVELOP...ESPECIALLY IN THE TYPICAL AREAS OF WC/SC MN WHERE GUSTS UP
TO 45 MPH WILL BE COMMON. WAS CONSIDERING A BLOWING SNOW PROBLEM IN
THESE AREAS...BUT DO TO A LACK OF SNOW COVER AND NO ADDITIONAL NEW
SNOW EXPECTED...DO NOT ANTICIPATE ANY CONCERNS.
VERY LITTLE CHC/S OF PRECIPITATION IS EXPECTED PAST TUESDAY
EVENING...WITH THE EXCEPTION BY NEXT MONDAY AS THE MEAN PATTERN WILL
REMAIN DRY AND UNEVENTFUL. TWO STRONG COLD FRONTS WILL MOVE ACROSS
OUR REGION...ONE WILL OCCUR TUESDAY AFTN/EVENING...AND ANOTHER
FRIDAY AFTN/SATURDAY MORNING. THESE FRONTS WILL CAUSE A FEW SNOW
SHOWERS TO DEVELOP...BUT AGAIN NOT EXPECTING MUCH IN THE WAY OF
ACCUMULATIONS.
OVER THE PAST TWO MONTHS...THE MEAN AREA OF ARCTIC AIR HAS REMAINED
ACROSS NE NORTH AMERICA...AFFECTING MAINLY THE NE CONUS...AND
EASTERN CANADA. ONCE IN A WHILE A BRIEF COLD SPELL MOVES ACROSS THE
UPPER MIDWEST/GREAT LAKES AS THE PATTERN BUCKLES. THE LATEST
PROBABILISTIC FORECASTS ON NCEP GEFS REFORECASTS CFS/V2...HAS 50H
ANOMALIES SHIFTING ACROSS THE ALASKA REGION...WITH A SECONDARY 50H
ANOMALY FOCUSING ACROSS THE DEEP SOUTH/SW. THIS BASICALLY SHIFTS THE
COLDER AIR ACROSS NORTHEAST CANADA FURTHER TO THE SW ACROSS THE
GREAT LAKES...AND THE EASTERN 1/3 OF NORTH AMERICA. THIS ALSO
SUGGESTS A STRONGER CORRELATION OF ABV NORMAL ANOMALIES FOCUSING
ACROSS THE GREAT BASIN AND THE FAR WEST COAST. THE TIME FRAME FOR
THIS PERIOD IS FEB 15 TO FEB 24. THE 45 DAY CFS PLUMES FOR THE PAST
4 RUNS DOES SUPPORT THE COLDER PATTERN DEVELOPING IN OUR REGION FOR
THE SECOND AND THIRD WEEK OF FEB 24. IN ADDITION...IT SEEMS IT MAYBE
A WETTER PATTERN AS THE STRONGER JET WORKS ACROSS THE CENTRAL
CONUS...LEADING TO A BETTER CHC OF A THERMAL BOUNDARY AND WIDESPREAD
PRECIPITATION.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 636 PM CST MON FEB 9 2015
WILL BE MAINTAINING VFR CONDITIONS ACROSS ERN MN AND WRN WI
THROUGH MUCH OF THE OVERNIGHT WITH MVFR OR LOWER CIGS HOLDING
NEARLY STATIONARY ACROSS WRN AND SRN MN. EVENTUALLY MOISTURE WILL
BEGIN INCHING EASTWARD TOWARD DAYBREAK WITH DETERIORATING
CONDITIONS. SNOW AND SLEET WILL BEGIN ACROSS WRN WI AROUND
09Z...WHICH WILL SPREAD EAST IN THE FORM OF A PRIMARY BAND THAT
COULD BECOME HEAVY AS IT HEADS INTO ERN MN MID MORNING AND WRN WI
LATE MORNING/EARLY AFTERNOON. HI-RES MODELS INDICATING 1-2 INCHES
OF SNOW PER HOUR WITH THIS BAND GIVEN ITS CONVECTIVE NATURE. IT IS
POSSIBLE THE TAFS ARE TOO OPTIMISTIC DURING THIS TIME.
ALSO...THESE HI-RES MODELS SHOW THE BAND ARRIVING ABOUT 2 HOURS
EARLIER THAN CURRENTLY FORECAST SO WILL MONITOR TRENDS THIS
EVENING. IT IS UNCLEAR HOW THINGS WILL EVOLVE BEHIND THIS BAND.
ACROSS SRN MN...THAT MAY MARK THE END OF PRECIP AS DRY SLOT LIFTS
NORTH. SHOULD CONTINUE SNOWING THROUGH AFTERNOON ACROSS WRN WI AND
CENTRAL MN...BUT WILL BE OF LIGHTER NATURE THAN WITH THE INITIAL
BAND.
KMSP...VFR FOR THE NEXT 12 HOURS. KEPT THE PRECIP START TIME OF
15Z...BUT THIS MAY NEED TO BE BUMPED UP AT SOME POINT ACCORDING TO
THE LATEST GUIDANCE. ALSO...IT IS BEGINNING TO LOOK LIKE THE BEST
CHANCE FOR HEAVY SNOW ARRIVES DURING THE LATE MORNING AS OPPOSED
TO AFTERNOON. WILL CONTINUE TO MONITOR.
/OUTLOOK FOR KMSP/
WED...MVFR WITH FLURRIES POSSIBLE. WINDS NW 15G30KT.
THU...BCMG VFR. WINDS BCMG LGT/VAR.
FRI...CHC MVFR CIGS. WINDS SW 5-10 KTS BCMG NW 15-20G25 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY FROM 6 AM TO 9 PM CST TUESDAY FOR MNZ041-
042-047>049-054>058-064.
WINTER WEATHER ADVISORY FROM 9 AM TUESDAY TO MIDNIGHT CST
TUESDAY NIGHT FOR MNZ043>045-050>053-059>063.
WI...WINTER WEATHER ADVISORY FROM 9 AM TUESDAY TO MIDNIGHT CST
TUESDAY NIGHT FOR WIZ014-015-023-025.
&&
$$
SHORT TERM...MPG
LONG TERM...JLT
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
601 AM CST SUN FEB 8 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 420 AM CST SUN FEB 8 2015
MAIN CONCERN IN THE SHORT TERM IS THE FIRST 6-8 HOURS OF THE
FORECAST DEALING WITH AN AREA OF FREEZING RAIN MOVING THROUGH
WESTERN AND SOUTHERN MINNESOTA. SURFACE TEMPERATURES HAVE LINGERED
NEAR THE FREEZING MARK...AND GRADUALLY COOLED JUST ENOUGH TO
CREATE ICING CONCERNS IN THIS AREA. THERE HAS BEEN CLARITY IN
TERMS OF PRECIP CHANCES ACROSS THE AREA...WITH THE OVERALL
CONSENSUS LINING UP WELL WITH THE PREVIOUS FORECAST KEEPING THE
PRECIP CONFINED TO FAR SOUTHERN MN. WAS ABLE TO SHARPLY DEFINE THE
NORTHERN FRINGE OF THE PRECIP CHANCES GIVEN RADAR TRENDS AND
AGREEMENT AMONG THE HI- RES GUIDANCE. OTHERWISE...EXPECTING THE
LOW LEVELS TO SATURATE THROUGH THE REMAINDER OF THE FA AS THE
MORNING WEARS ON...BUT GUIDANCE HAS CONTINUALLY DELAYED THE ONSET
THE LOW LEVEL STRATUS OVERTAKING THE REGION.
CONTINUED SLIGHT CHANCE POPS ACROSS THE WEST TONIGHT...AS MODEST
LIFT MOVES IN. MAY STRUGGLE TO SATURATE SO DID NOT FEEL CONFIDENT
IN GOING ANY HIGHER THAN 20 PERCENT AT MOST IN THE FORECAST
THERE. STRONG COLD AIR ADVECTION IN THE LOW LEVELS WILL PREVENT
TEMPERATURES FROM RISING MUCH TODAY...850MB TEMPS YESTERDAY FROM
+10 TO +15C ACROSS THE REGION WILL FALL BELOW 0C TODAY. THIS ALSO
MEANS A COOLER NIGHT IS IN STORE FOR TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 400 AM CST SUN FEB 8 2015
UPR LVL RIDGING OVER THE WRN CONUS WILL SHIFT EWD ON MON ATOP SFC
HIGH PRES...MAKING FOR DRY CONDS BUT ALSO THE START OF ANOTHER
MODEST WARMING TREND. A FEW BUBBLES IN THE FLOW WILL AID IN
KEEPING ANY POTENTIAL PRECIP FROM AFFECTING THE AREA ON MON. THE
RIDGE WILL BEGIN TO FLATTEN OUT MON EVE THRU MON NIGHT WHILE A
LONGWAVE TROF MOVES ONSHORE THE PAC NW. PLENTY OF PACIFIC MOISTURE
WILL ACCOMPANY THIS TROF AS IT SHIFTS EWD OVER THE ROCKIES TUE.
THE FLATTENING FLOW ALOFT WILL MAKE FOR AN EFFICIENT CONDUIT FOR
THE DEEPER MOISTURE TO STREAM INTO THE N-CENTRAL CONUS MON NIGHT
THRU TUE IN CONJUNCTION WITH SEVERAL SHORTWAVE TROF DISTURBANCES
ALOFT. MEANWHILE...AT THE SFC...AN AREA OF LOW PRES ASSOCIATED
WITH THE UPR LVL TROF WILL MOVES OVER THE NRN ROCKIES AND EJECT
INTO THE NRN PLAINS...BECOMING MORE ORGANIZED TUE INTO TUE NIGHT.
ISENTROPIC LIFT AT MULTIPLE LEVELS IN ADVANCE OF THE SFC LOW PRES
FEATURE INCRS LATE MON THRU TUE...ALLOWING PRECIP TO SPREAD ACRS
THE ENTIRE CWFA TUE. THE AFOREMENTIONED WARMING TREND...
PARTICULARLY IN THE BLYR...WILL AGAIN MAKE FOR A MIXTURE OF PRECIP
BUT THE CONCERN IN THIS FCST PKG OVER PREVIOUS RUNS IS THE
NOTICEABLE INCRS IN QPF. THIS WILL SPELL NOT ONLY A POTENTIAL
INCRS IN SNOW AMOUNTS TO THE 1-3 INCH RANGE BUT ALSO THE
POTENTIAL FOR ICING NEARLY UP TO A TENTH OF AN INCH. THE BETTER
SNOWFALL AMOUNTS WILL BE IN THE NRN HALF OF THE WFO MPX CWFA WHILE
THE BETTER ICING AMOUNTS WILL BE CLOSER TO THE IA BORDER. WHILE
THERE IS STILL SOME UNCERTAINTY AS TO WHERE THE ICE/SNOW
DELINEATION WILL BE AND TO THE QPF...AND HENCE SNOW/ICE AMOUNTS...
CONFIDENCE IS HIGH ENOUGH TO INCLUDE LIKELY POPS FOR THIS EVENT...
WHICH WILL BE MAINLY TUE INTO TUE EVE. THE SFC LOW PRES WILL TRACK
FROM SD ACRS SRN MN TO THE LWR GRT LAKES BY WED MRNG...BRINGING AN
END TO ANY AND ALL PRECIP BY THAT TIME. CANADIAN HIGH PRES WILL
DROP THRU THE REGION LATE WED THRU THU NIGHT...ALLOWING FOR
CLEARING BUT ALSO NOTICEABLY COLDER TEMPERATURES TO SETTLE OVER
THE REGION. ONCE THE HIGH PRES SHIFTS OFF TO THE SE...WARMER
RETURN FLOW ON THE BACKSIDE WILL MAKE FOR SOME MODERATION FOR THE
END OF THE WEEK. HOWEVER...SEVERAL WEAK SHORTWAVE DISTURBANCES
ALOFT DRIVING SE WITHIN THE NW FLOW MAY SPARK OFF A FEW SNOW
SHOWERS FOR MAINLY THE ERN HALF OF THE COVERAGE AREA FRI AND AGAIN
LATE SAT...BUT NOTHING SIGNIFICANT IS EXPECTED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 553 AM CST SUN FEB 8 2015
FORECAST HAS BECOME MORE AND MORE OPTIMISTIC. STARTING WITH THE
PRECIP...REMOVED ANY MENTION OF PRECIP AT ALL TAF SITES EXCEPT
RWF...WHICH WAS THE MOST HEAVILY IMPACTED TAF SITE BY THE
OVERNIGHT FREEZING RAIN DEVELOPMENT. OTHERWISE...THE PRECIPITATION
WILL CONTINUE TO REMAIN SOUTH OF THE OTHER TAF SITES. LOW LEVELS
HAVING TROUBLE SATURATING AS QUICKLY AS ONCE THOUGHT...AND EVEN
THE AREAS SEEING PRECIP ARE SEEING LOWEST CLOUD BASES AROUND 5K
FEET. FOLLOWED THE RAP 0.5KM CPD CLOSELY IN TIMING IN THE STRATUS
THIS MORNING...AS IT SEEMS TO BE HANDLING THE CURRENT SITUATION
QUITE WELL. THIS MEANT DELYAING THE ONSET OF THE LOWER CEILINGS A
COUPLE OF HOURS AND ALSO RAISING THE EXPECTED VSBYS. NAM MODEL
SOUNDINGS INDICATE ONCE THE CLOUDS SPREAD THROUGH THE
REGION...THEY`LL BE ESSENTIALLY HERE TO STAY THROUGH THIS TAF
PERIOD.
KMSP...MAIN PRECIP SLUG TO REMAIN SOUTH OF MSP. COULD SEE A FEW
FLURRIES LATER THIS MORNING BUT NOTHING MEASURABLE EXPECTED TO
FALL. EXPECT THE CLOUDS TO STAY IN PLACE FOR A WHILE ONCE THEY
FINALLY ARRIVE.
/OUTLOOK FOR KMSP/
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...FREEZING RAIN ADVISORY UNTIL 10 AM CST THIS MORNING FOR
MNZ054>056-064-065-067-073>076-082>085-091>093.
WI...NONE.
&&
$$
SHORT TERM...SPD
LONG TERM...JPC
AVIATION...SPD
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
424 AM CST SUN FEB 8 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 420 AM CST SUN FEB 8 2015
MAIN CONCERN IN THE SHORT TERM IS THE FIRST 6-8 HOURS OF THE
FORECAST DEALING WITH AN AREA OF FREEZING RAIN MOVING THROUGH
WESTERN AND SOUTHERN MINNESOTA. SURFACE TEMPERATURES HAVE LINGERED
NEAR THE FREEZING MARK...AND GRADUALLY COOLED JUST ENOUGH TO
CREATE ICING CONCERNS IN THIS AREA. THERE HAS BEEN CLARITY IN
TERMS OF PRECIP CHANCES ACROSS THE AREA...WITH THE OVERALL
CONSENSUS LINING UP WELL WITH THE PREVIOUS FORECAST KEEPING THE
PRECIP CONFINED TO FAR SOUTHERN MN. WAS ABLE TO SHARPLY DEFINE THE
NORTHERN FRINGE OF THE PRECIP CHANCES GIVEN RADAR TRENDS AND
AGREEMENT AMONG THE HI- RES GUIDANCE. OTHERWISE...EXPECTING THE
LOW LEVELS TO SATURATE THROUGH THE REMAINDER OF THE FA AS THE
MORNING WEARS ON...BUT GUIDANCE HAS CONTINUALLY DELAYED THE ONSET
THE LOW LEVEL STRATUS OVERTAKING THE REGION.
CONTINUED SLIGHT CHANCE POPS ACROSS THE WEST TONIGHT...AS MODEST
LIFT MOVES IN. MAY STRUGGLE TO SATURATE SO DID NOT FEEL CONFIDENT
IN GOING ANY HIGHER THAN 20 PERCENT AT MOST IN THE FORECAST
THERE. STRONG COLD AIR ADVECTION IN THE LOW LEVELS WILL PREVENT
TEMPERATURES FROM RISING MUCH TODAY...850MB TEMPS YESTERDAY FROM
+10 TO +15C ACROSS THE REGION WILL FALL BELOW 0C TODAY. THIS ALSO
MEANS A COOLER NIGHT IS IN STORE FOR TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 400 AM CST SUN FEB 8 2015
UPR LVL RIDGING OVER THE WRN CONUS WILL SHIFT EWD ON MON ATOP SFC
HIGH PRES...MAKING FOR DRY CONDS BUT ALSO THE START OF ANOTHER
MODEST WARMING TREND. A FEW BUBBLES IN THE FLOW WILL AID IN
KEEPING ANY POTENTIAL PRECIP FROM AFFECTING THE AREA ON MON. THE
RIDGE WILL BEGIN TO FLATTEN OUT MON EVE THRU MON NIGHT WHILE A
LONGWAVE TROF MOVES ONSHORE THE PAC NW. PLENTY OF PACIFIC MOISTURE
WILL ACCOMPANY THIS TROF AS IT SHIFTS EWD OVER THE ROCKIES TUE.
THE FLATTENING FLOW ALOFT WILL MAKE FOR AN EFFICIENT CONDUIT FOR
THE DEEPER MOISTURE TO STREAM INTO THE N-CENTRAL CONUS MON NIGHT
THRU TUE IN CONJUNCTION WITH SEVERAL SHORTWAVE TROF DISTURBANCES
ALOFT. MEANWHILE...AT THE SFC...AN AREA OF LOW PRES ASSOCIATED
WITH THE UPR LVL TROF WILL MOVES OVER THE NRN ROCKIES AND EJECT
INTO THE NRN PLAINS...BECOMING MORE ORGANIZED TUE INTO TUE NIGHT.
ISENTROPIC LIFT AT MULTIPLE LEVELS IN ADVANCE OF THE SFC LOW PRES
FEATURE INCRS LATE MON THRU TUE...ALLOWING PRECIP TO SPREAD ACRS
THE ENTIRE CWFA TUE. THE AFOREMENTIONED WARMING TREND...
PARTICULARLY IN THE BLYR...WILL AGAIN MAKE FOR A MIXTURE OF PRECIP
BUT THE CONCERN IN THIS FCST PKG OVER PREVIOUS RUNS IS THE
NOTICEABLE INCRS IN QPF. THIS WILL SPELL NOT ONLY A POTENTIAL
INCRS IN SNOW AMOUNTS TO THE 1-3 INCH RANGE BUT ALSO THE
POTENTIAL FOR ICING NEARLY UP TO A TENTH OF AN INCH. THE BETTER
SNOWFALL AMOUNTS WILL BE IN THE NRN HALF OF THE WFO MPX CWFA WHILE
THE BETTER ICING AMOUNTS WILL BE CLOSER TO THE IA BORDER. WHILE
THERE IS STILL SOME UNCERTAINTY AS TO WHERE THE ICE/SNOW
DELINEATION WILL BE AND TO THE QPF...AND HENCE SNOW/ICE AMOUNTS...
CONFIDENCE IS HIGH ENOUGH TO INCLUDE LIKELY POPS FOR THIS EVENT...
WHICH WILL BE MAINLY TUE INTO TUE EVE. THE SFC LOW PRES WILL TRACK
FROM SD ACRS SRN MN TO THE LWR GRT LAKES BY WED MRNG...BRINGING AN
END TO ANY AND ALL PRECIP BY THAT TIME. CANADIAN HIGH PRES WILL
DROP THRU THE REGION LATE WED THRU THU NIGHT...ALLOWING FOR
CLEARING BUT ALSO NOTICEABLY COLDER TEMPERATURES TO SETTLE OVER
THE REGION. ONCE THE HIGH PRES SHIFTS OFF TO THE SE...WARMER
RETURN FLOW ON THE BACKSIDE WILL MAKE FOR SOME MODERATION FOR THE
END OF THE WEEK. HOWEVER...SEVERAL WEAK SHORTWAVE DISTURBANCES
ALOFT DRIVING SE WITHIN THE NW FLOW MAY SPARK OFF A FEW SNOW
SHOWERS FOR MAINLY THE ERN HALF OF THE COVERAGE AREA FRI AND AGAIN
LATE SAT...BUT NOTHING SIGNIFICANT IS EXPECTED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1227 AM CST SUN FEB 8 2015
00Z RAOB AT MPX WAS VERY DRY IN A LARGE LAYER FROM 900MB-500MB.
SLOWLY THE COLUMN IS BECOMING SATURATED FROM THE TOP DOWN...AND
SOME RETURNS ARE CURRENTLY PRESENT ON THE LATEST RADAR IMAGERY.
MUCH OF THIS PRECIPITATION IS NOT REACHING THE GROUND
HOWEVER...THANKS TO THE DRY LOWER LEVEL AIR. LATEST RAP SOUNDINGS
STILL INDICATE DEW POINT DEPRESSIONS IN EXCESS OF 20 DEGREES AT
800MB OVER PARTS OF THE AREA. IN TERMS OF EXPECTATIONS WITH THE
PRECIP AND CLOUD COVER...GUIDANCE HAS TURNED MORE OPTIMISTIC AND
MODELS HAVE TRENDED THE PRECIP FURTHER SOUTHWEST. DOWNPLAYED
PRECIP AT ALL SITES EXCEPT RWF WHICH IS SEEING SOME LIGHT PRECIP
REACHING THE GROUND AT THIS TIME. THE HRRR/RAP REALLY BACKED OFF
ON THE TIMING OF SUB 3K FT CEILINGS TONIGHT...SO PUSHED THOSE BACK
AT ALL SITES. ACCUMULATING PRECIP WILL BE CONFINED TO SOUTH OF THE
TWIN CITIES.
KMSP...HRRR/RAP BOTH INDICATE THE PRECIP REMAINING SOUTH OF MSP
AND INDICATED AN OPTIMISTIC FORECAST FOR CEILINGS OVERNIGHT. CPD`S
LINE UP WELL WITH 925MB RH FIELDS AND SHOW A DRY WEDGE THROUGH
EASTERN MN MUCH OF THE NIGHT. VIS WILL CONTINUE TO HOLD STEADY
AROUND 5SM MOST OF THE NIGHT. SOME OF THE HI-RES GUIDANCE EVEN
SUGGESTS PUSHING BACK THE LOW CEILINGS BEYOND 15Z...WILL SEE IF
THIS SIGNAL IS CONSISTENTLY SHOWN OVER THE NEXT FEW HOURS AND
WILL UPDATE AS NECESSARY.
/OUTLOOK FOR KMSP/
MON-MON NIGHT...VFR. VRBL WIND LESS THAN 10 KT BCMG SE 5-10 KT.
TUE-TUE NIGHT...MVFR CONDS EXPECTED...IFR POSSIBLE...WITH A CHC
OF -SNOW OR MIXED PRECIP. SE WIND 5-15 KT SHIFTING NW LATE.
WED...MVFR CONDS POSSIBLE WITH ISOLD -SHSN. NW WIND 15-20 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...FREEZING RAIN ADVISORY UNTIL 10 AM CST THIS MORNING FOR
MNZ074>076-082>085-091>093.
FREEZING RAIN ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
MNZ054>056-064-065-067-073.
WI...NONE.
&&
$$
SHORT TERM...SPD
LONG TERM...JPC
AVIATION...SPD
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1240 AM CST SUN FEB 8 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 328 PM CST SAT FEB 7 2015
EARLY AFTERNOON WATER VAPOR IMAGERY IDENTIFIED TWO SHORTWAVES
ACROSS THE UPPER MIDWEST. THE FIRST WAS LOCATED ALONG THE
MINNESOTA/CANADA BORDER...AND WAS PRODUCING SOME 1-2MI VISIBILITY
SNOW NORTH OF THE INTERNATIONAL BORDER. THE SECOND WAS LOCATED
OVER WYOMING...AND THIS WILL LEAD TO A LIGHT WINTRY MIX LATER
TONIGHT AND SUNDAY MORNING.
FORECAST MODELS ARE IN GOOD AGREEMENT WITH THE TIMING OF THE SECOND
SHORTWAVE. THE ECMWF CONTINUES TO BE FARTHEST SOUTH WITH THE MODEL
GENERATED PRECIP...GENERALLY SOUTH OF THE UPPER MINNESOTA RIVER
VALLEY. MEANWHILE THE GFS/NAM/SREF ARE DISPLACED SLIGHTLY NORTH.
TOTAL AMOUNTS WILL ONLY RANGE FROM A TRACE TO A FEW HUNDREDTHS...BUT
THE PRECIP TYPE CONTINUES TO BE THE MAIN CHALLENGE. A WARM LAYER
ALOFT TOGETHER WITH SUBFREEZING TEMPERATURES WILL LEAD TO A MIXTURE
OF FREEZING RAIN/SLEET INITIALLY. AS THIS WARM LAYER COOLS...EXPECT
A TRANSITION TO SLEET/SNOW...FINALLY ENDING WITH MAINLY SNOW.
HOWEVER ICE CRYSTALS WILL GRADUALLY DIMINISH SUNDAY
AFTERNOON/EVENING...SO COULD SEE SOME FREEZING DRIZZLE RETURN ACROSS
THE SOUTHERN/WESTERN CWA. CHOSE NOT TO ISSUE HEADLINES AT THIS
POINT...BUT WOULD RATHER SEE HOW THE CAMS HANDLE THIS AREA OF LIGHT
PRECIP...AND MAY NEED AN ADVISORY IF LIGHT ICING DOES INDEED COME TO
FRUITION.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 PM CST SAT FEB 7 2015
WEST/NORTHWEST MID LEVEL FLOW WILL FOSTER MULTIPLE PRECIPITATION
CHANCES AT THE START OF THE UPCOMING WEEK...AND THEN A TRANSITION
TO WESTERN CONUS RIDGING AND EASTERN CONUS TROUGHING WILL LEAVE
THE LOCAL AREA IN A SOMEWHAT BENIGN WEATHER REGIME.
SUNDAY NIGHT A WEAK SURFACE TROUGH WILL BE LOCATED JUST TO THE
SOUTHWEST OF THE FORECAST AREA...AS A WEAK SHORTWAVE OVERRIDES THE
LOW LEVEL BOUNDARY. LACK OF MOISTURE IN THE CRITICAL DENDRITIC
LAYER WILL MEAN ANOTHER CHANCE FOR LIGHT FREEZING
PRECIPITATION...PRIMARILY ALONG AND SOUTH OF THE MN RIVER VALLEY.
MONDAY SHOULD BE AN OVERALL DRY BUT RELATIVELY CLOUDY DAY IN
BETWEEN WAVES...WITH MILD TEMPS IN THE MID 20S TO LOWER 30S.
TUESDAY BRINGS THE ARRIVAL OF SHORTWAVE ENERGY FROM THE PACIFIC
NORTHWEST. THE AMOUNT OF MILD AIR PULLED INTO THE REGION WILL MEAN
FREEZING PRECIPITATION ISSUES WILL AGAIN BE OF CONCERN. HAVE
INCLUDED A MENTION OF SNOW AND LIGHT FREEZING RAIN FOR TUESDAY
INTO TUESDAY EVENING.
SURFACE HIGH PRESSURE BUILDS IN FOR WEDNESDAY...WITH A BRIEF
RETURN TO BELOW NORMAL TEMPERATURES FOR WEDNESDAY NIGHT INTO
THURSDAY. SHOULD SEE LOWS FROM ZERO TO 10 BELOW...WITH THURSDAY
HIGHS IN THE TEENS.
THE HIGH SHIFTS OFF TO THE EAST AND ALLOWS RETURN FLOW TO SETUP
FOR FRIDAY. HIGHS SHOULD REBOUND ACCORDINGLY...WITH LOWER 20S/30S
ANTICIPATED.
A FAINT TROUGH IS DEPICTED FOR FRIDAY NIGHT INTO SATURDAY. AT THIS
POINT HAVE JUST REDUCED TEMPS A BIT INTO THE TEENS AND LOWER 20S
FOR SATURDAY...ALTHOUGH IT COULD MEAN ANOTHER ROUND OF LIGHT
PRECIPITATION TO START NEXT WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1227 AM CST SUN FEB 8 2015
00Z RAOB AT MPX WAS VERY DRY IN A LARGE LAYER FROM 900MB-500MB.
SLOWLY THE COLUMN IS BECOMING SATURATED FROM THE TOP DOWN...AND
SOME RETURNS ARE CURRENTLY PRESENT ON THE LATEST RADAR IMAGERY.
MUCH OF THIS PRECIPITATION IS NOT REACHING THE GROUND
HOWEVER...THANKS TO THE DRY LOWER LEVEL AIR. LATEST RAP SOUNDINGS
STILL INDICATE DEW POINT DEPRESSIONS IN EXCESS OF 20 DEGREES AT
800MB OVER PARTS OF THE AREA. IN TERMS OF EXPECTATIONS WITH THE
PRECIP AND CLOUD COVER...GUIDANCE HAS TURNED MORE OPTIMISTIC AND
MODELS HAVE TRENDED THE PRECIP FURTHER SOUTHWEST. DOWNPLAYED
PRECIP AT ALL SITES EXCPET RWF WHICH IS SEEING SOME LIGHT PRECIP
REACHING THE GROUND AT THIS TIME. THE HRRR/RAP REALLY BACKED OFF
ON THE TIMING OF SUB 3K FT CEILINGS TONIGHT...SO PUSHED THOSE BACK
AT ALL SITES. ACCUMULATING PRECIP WILL BE CONFINED TO SOUTH OF THE
TWIN CITIES.
KMSP...HRRR/RAP BOTH INDICATE THE PRECIP REMAINING SOUTH OF MSP
AND INDICATED AN OPTIMISTIC FORECAST FOR CEILINGS OVERNIGHT. CPD`S
LINE UP WELL WITH 925MB RH FIELDS AND SHOW A DRY WEDGE THROUGH
EASTERN MN MUCH OF THE NIGHT. VIS WILL CONTINUE TO HOLD STEADY
AROUND 5SM MOST OF THE NIGHT. SOME OF THE HI-RES GUIDANCE EVEN
SUGGESTS PUSHING BACK THE LOW CEILINGS BEYOND 15Z...WILL SEE IF
THIS SIGNAL IS CONSISTENLY SHOWN OVER THE NEXT FEW HOURS AND WILL
UPDATE AS NECESSARY.
/OUTLOOK FOR KMSP/
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
UPDATE...
SHORT TERM...JRB
LONG TERM...LS
AVIATION...SPD
AREA FORECAST DISCUSSION
NWS BILLINGS MT
246 PM MST SUN FEB 8 2015
.SHORT TERM...VALID FOR MON AND TUE...
BUILDING UPPER RIDGE WILL BRING DRY WX TO OUR AREA TONIGHT. WEAK
PRESSURE RISE ASSOCIATED WITH SHORTWAVE IN SASKATCHEWAN WILL SLIDE
INTO THE DAKOTAS...ALLOWING FOR A SHIFT TO EASTERLY WINDS IN OUR
EAST. MUCH COOLER AIR AND FOG/STRATUS EXIST FROM SOUTHERN
SASKATCHEWAN INTO NORTH DAKOTA...AND THE WIND SHIFT WILL ADVECT A
PORTION OF THIS AIRMASS INTO OUR NORTHEAST PARTS TONIGHT. HRRR AND
MET GUIDANCE SHOW A STRONG POSSIBILITY OF FOG/STRATUS INTO FALLON
COUNTY OVERNIGHT...AND PERHAPS AS FAR WEST AND SOUTH AS FORSYTH
AND EKALAKA. WILL ADD MENTION OF FOG TO THESE AREAS LATE TONIGHT
AND MONDAY MORNING.
DEEPER TROF OFF THE PACIFIC COAST WILL PUSH INLAND TOMORROW.
EXPECT INCREASING SHOWER ACTIVITY MONDAY AND MONDAY NIGHT AS THIS
ENERGY AND PACIFIC COLD FRONT MOVE THROUGH THE AREA...THOUGH WITH
DOWNSLOPE WINDS CONTINUING THE BEST POTENTIAL WILL BE OVER OUR
MTNS AND IN THE EAST. OUR WESTERN MOUNTAINS SHOULD PICK UP SOME
SNOWFALL. THERE IS A SLIGHT RISK OF MIXED PCPN IN OUR FAR EAST
MONDAY EVENING...DEPENDING ON HOW COOL IT STAYS TOMORROW PER THE
EASTERLY WINDS...BUT OTHERWISE LOWER ELEVATION PCPN TYPE WILL BE
RAIN IN THIS PERSISTENT WARM REGIME. HIGH TEMPS MONDAY WILL STILL
PUSH 60 DEGREES MOST PLACES.
LEE SIDE PRESSURE FALLS MONDAY/MONDAY NIGHT SHOULD YIELD GUSTY
WINDS ALONG OUR FOOTHILLS...BUT WITH MID LEVEL FLOW ON THE ORDER
OF 30-40 KTS THEY SHOULD STAY UNDER ADVISORY CRITERIA. HAVE
NONETHELESS RAISED WIND SPEEDS FROM LIVINGSTON TO NYE AND EVEN
RED LODGE AND DAYTON DURING THESE PRE-FRONTAL PERIODS. THINKING
GUSTS IN THE 40S MPH.
THINGS GET A LITTLE MORE INTERESTING TUESDAY AND TUESDAY NIGHT AS
CANADIAN SFC HIGH SLIDES INTO EASTERN MT. WEAK SHORTWAVE ACTIVITY
ALONG WITH LOW LEVEL FRONTOGENESIS UNDER NW FLOW ALOFT SUGGEST
SOME NW-SE ORIENTED PCPN BANDS DEVELOPING BY TUESDAY AFTERNOON...
WITH SFC TEMPS TURNING SUFFICIENTLY COLD FOR SNOW AS WE COLD
ADVECT FROM THE NORTH. WOULD EXPECT SOME SNOWFALL IN OUR CENTRAL
PARTS INCLUDING BILLINGS TUESDAY AFTERNOON AND EARLY EVENING...
SHIFTING TOWARD OUR FOOTHILLS BY EVENING PER PRESSURE RISES
BUILDING IN FROM THE N-NE. HAVE RAISED POPS AND SNOW AMOUNTS A BIT
FROM PREVIOUS FORECAST...AND THOUGH THIS WILL NOT BE A SIGNIFICANT
EVENT WE COULD SEE A QUICK 1-2 INCH SNOWFALL IN THE BANDED
AREAS...MOST LIKELY ALONG OUR SOUTHERN FOOTHILLS. RISING HEIGHTS
AND DEPARTURE OF SHORTWAVE ENERGY WILL DIMINISH PCPN CHANCES BY
LATE TUESDAY NIGHT.
CANADIAN SFC HIGH WILL BRING THE COLDEST AIR WE HAVE SEEN SINCE
EARLY FEBRUARY...WITH TEENS FOR LOWS ACROSS OUR EAST HALF TUESDAY
NIGHT.
JKL
.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...
THE EXTENDED IS GENERALLY QUIET...AT LEAST THROUGH THE END OF THE
WEEK. THE COLD AIR WILL BEGIN MOVING OUT ON WEDNESDAY.
TEMPERATURES WILL STILL BE IN THE 40S FOR HIGHS DURING THE DAY. THE
WARM UP WILL BEGIN IN ERNEST THURSDAY AS THE RIDGE REALLY BUILDS
BACK IN AND WESTERLY WINDS ALOFT RETURN. WITH DOWNSLOPE
WARMING...TEMPERATURES WILL REBOUND BACK INTO THE MID TO UPPER
50S ON THURSDAY AND WILL CONTINUE TO BE WELL ABOVE NORMAL THROUGH
SATURDAY.
SUNDAY...AND MAINLY SUNDAY NIGHT...PRECIP CHANCES RETURN. THERE
ARE SIGNIFICANT DIFFERENCE BETWEEN THE MODELS ON TIMING. GIVEN
THAT YESTERDAY THERE LOOKED TO BE A CHANCE ON SATURDAY AND CURRENT
RUNS LOOK DRY FOR SATURDAY...CONFIDENCE IN THE TIMING WITH ANY
SOLUTION IS LOW. MOSTLY USING A BLEND OF THE MODELS FOR SUNDAY AND
SUNDAY NIGHT. REIMER
&&
.AVIATION...
WINDS WILL BEGIN TO CALM DOWN THIS EVENING...THOUGH AROUND
LIVINGSTON EXPECT WINDS TO REMAIN A BIT GUSTY. VFR CONDITIONS WILL
PREVAIL FOR MUCH OF THE AREA THROUGH TOMORROW. THE ONE EXCEPTION
WILL BE FOG DEVELOPING TONIGHT AROUND MILES CITY. ENSEMBLE
GUIDANCE HAS HIGH PROBABILITY OF VISIBILITIES DROPPING TO LESS
THAN A MILE. BASED ON SOUNDINGS...FOG COULD PERSIST THROUGH MUCH
OF THE MORNING. REIMER
&&
.PRELIMINARY POINT TEMP/POPS...
MON TUE WED THU FRI SAT SUN
-----------------------------------------------------------
BIL 036/060 041/049 024/048 032/058 038/058 038/058 036/050
02/W 25/W 41/B 00/B 00/B 01/B 12/R
LVM 038/058 040/049 029/051 035/055 039/057 039/057 036/051
13/W 24/W 51/B 01/N 11/N 11/N 12/R
HDN 032/060 035/048 022/045 026/056 032/057 032/057 032/049
02/W 25/W 21/B 00/B 01/B 01/B 12/R
MLS 031/052 032/043 017/035 020/051 030/052 030/051 029/045
02/W 32/W 10/B 00/B 01/B 01/B 12/O
4BQ 031/059 035/049 019/042 025/056 034/056 033/058 031/049
02/W 33/W 10/B 00/B 01/B 01/B 12/O
BHK 026/049 031/041 014/030 014/048 028/049 027/047 025/041
02/W 32/W 10/B 00/B 01/B 11/B 22/O
SHR 028/061 034/049 022/047 025/058 032/057 031/058 030/051
02/W 23/W 41/B 00/B 01/B 00/B 13/R
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
858 PM CST MON FEB 9 2015
.SYNOPSIS...
ISSUED AT 254 PM CST MON FEB 9 2015
AT H5 TROUGH FROM GREAT LAKES INTO FLORIDA PANHANDLE WITH
ASSOCIATED PRECIPITATION ALL ALONG THE EASTERN SEABOARD. RIDGE
INTO THE NORTHERN PLAINS WITH FAIRLY STRONG WAVE MOVING ACROSS THE
PACIFIC NORTHWEST.
&&
.UPDATE...
ISSUED AT 857 PM CST MON FEB 9 2015
RELEASED A SECOND UPDATE TO BETTER DEPICT HOW FAR WEST THE FOG
WILL MAKE IT INTO THE OVERNIGHT. BASED ON THE LATEST HRRR AND
NAM12...00Z VERSION...HAVE THE FOG GOING AS FAR WEST AS A LINE
FROM CURTIS...TO ARNOLD...TO NEAR VALENTINE. BASED ON OBS AT ONEILL
AND ORD...DECIDED TO HOIST A DENSE FOG ADVISORY FOR PORTIONS OF
THE EASTERN SANDHILLS AND PORTIONS OF NORTH CENTRAL NEBRASKA. THIS
WILL BE IN EFFECT UNTIL 9 AM CST TUESDAY MORNING. FOR LOCATIONS
ALONG THE WESTERN PERIPHERY OF THE FOG...THIS SHOULD BEGIN TO MOVE
SLOWLY EAST OVERNIGHT AS SURFACE WINDS SHIFT AROUND TO THE
SOUTHWEST AND WEST AS LOW PRESSURE ENTERS SOUTH DAKOTA.
UPDATE ISSUED AT 752 PM CST MON FEB 9 2015
JUST RELEASED AN UPDATED FORECAST TO ADDRESS THE FOG AND STRATUS
ACROSS EASTERN PORTIONS OF THE FORECAST AREA. LOOKING AT THE
HRRR...LATEST NAM12 SOLN AND SREF DATA...DECIDED TO PUSH FOG
FURTHER WEST UP TO THE HIGHWAY 83 CORRIDOR THIS EVENING. THE
MODELS DO SHIFT THIS EAST OVERNIGHT AS THE LOW LEVEL WINDS SHIFT
TO THE WEST...SO FOG WILL PEAK AROUND MIDNIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 254 PM CST MON FEB 9 2015
MAIN FORECAST CONCERN FOR THE OVERNIGHT REVOLVES AROUND THE WESTWARD
RETURN OF STRATUS AND/OR FOG. THE NAM MODEL IS ONCE AGAIN THE MOST
BULLISH WITH REDUCED VISIBILITY...BRINGING DENSE FOG AS FAR WEST AS
THE HIGHWAY 83 CORRIDOR. THE HRRR SEEMS TO BE A GOOD COMPROMISE FOR
NOW...WHICH INDICATES FOG IN THE SAME GENERAL AREA AS SEEN EARLIER
TODAY. SURFACE LOW PRESSURE IS SHOWN TO MOVE EAST ACROSS SOUTHERN
SOUTH DAKOTA OVERNIGHT...DRAGGING A TROUGH THROUGH THE
SANDHILLS...SO AM EXPECTING A GREATER WESTWARD...OR
SOUTHWEST...TRAJECTORY OF THE LOWER TROPOSPHERIC WIND...WHICH WILL
DRAW DRY LOW LEVEL AIR BACK INTO THE REGION. THIS BOUNDARY IS SHOWN
TO BE ALONG OR NEAR HIGHWAY 281 BY 12Z TOMORROW. FOR THIS...WOULD
EXPECT SOME IMPROVEMENT IN VISIBILITY AND SKY COVER FROM WEST TO
EAST THROUGH THE OVERNIGHT HOURS AND THE STRATUS SHOULD ONLY BE
CONFINED TO OUR FAR EAST.
A WEAK UPPER LEVEL DISTURBANCE/PV ANOMALY WILL CROSS THE
CENTRAL/NORTHERN PLAINS OVERNIGHT PROVIDING FOR A LEAST A SLIGHT
CHANCE OF PRECIPITATION ACROSS OUR FAR NORTHEAST. THE MODELS ARE
KEYING ON THE GREATEST FORCING WELL NORTH OF THE FORECAST AREA...AND
WITH SATURATION CONFINED TO THE LOWER TROPOSPHERE...RAIN WILL BE
DIFFICULT. AM LEANING TOWARD A DRIZZLE POTENTIAL...OR VERY LIGHT
RAIN...IF PRECIPITATION WERE TO BE REALIZED. ANY LIFT IS QUICKLY
EAST OF THE FORECAST AREA BY 12Z TUESDAY...BEYOND THAT...THE REST OF
THE DAY APPEARS DRY.
TEMPERATURES OVERNIGHT WILL BE MILD AS WAA SPREADS EAST AHEAD OF THE
PASSING SURFACE TROUGH. FORECAST LOWS RANGE FROM THE UPPER 20S IN
THE RIVER VALLEYS...TO THE MID 30S ACROSS THE HEART OF THE SANDHILLS
WHERE GREATER MIXING IS ANTICIPATED. FOR TUESDAY...THE DISTURBANCE
WILL DRAW SLIGHTLY COOLER AIR ACROSS WEST CENTRAL NEBRASKA. HIGHS
WERE TRENDED ACCORDINGLY...WITH MOST LOCATIONS SEEING A DROP OF 5-7F
FROM WHAT WAS OBSERVED TODAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 254 PM CST MON FEB 9 2015
MODELS IN FAIR AGREEMENT IN MID TERM AND THEN HAVING SOME
VARIABILITY IN LONG TERM SOLUTIONS. TUESDAY NIGHT COOLER AIR
FILTERS IN ACROSS THE NORTHERN PLAINS INTO WESTERN NEBRASKA. WITH
THE UPPER RIDGE IN PLACE THE HIGH PRESSURE WILL BE MOVED FURTHER
EAST WITH A STATIONARY BOUNDARY FROM THE NORTHERN NEBRASKA
PANHANDLE INTO BROKEN BOW. WARMER 40S TO THE SOUTHWEST AND 30S TO
THE NORTHEAST. LOWS WEDNESDAY NIGHT QUITE COLD WITH MOSTLY CLEAR
SKIES AND LIGHT WINDS. SINGLE DIGITS ONEILL AND LOW 20S OVER
SOUTHWEST NEBRASKA. SOUTHERLY WINDS THURSDAY WILL MODERATE
TEMPERATURES SOME WHAT ON THE BACKSIDE OF THE SURFACE HIGH. MILD
NIGHT THURSDAY NIGHT WITH RETURN FLOW. FRIDAY TEMPERATURES REBOUND
INTO THE 40S NORTH AND 50S SOUTH. A DRY BACKDOOR COLD FRONT WILL
MOVE ACROSS THE FORECAST AREA FRIDAY NIGHT INTO SATURDAY WITH
HIGHS ON SATURDAY RANGING FROM THE 20S ONEILL TO MID 40S IMPERIAL.
TEMPERATURES REBOUND SUNDAY WITH 40S NORTH AND 50S SOUTH IN RETURN
FLOW. INCREASING MOISTURE ACROSS THE SOUTHERN PLAINS SUNDAY AND AN
ARCTIC COLD FRONT MOVING SOUTH ACROSS THE NORTHERN PLAINS WILL SEE
A RETURN TO SNOW IN THE FORECAST SUNDAY NIGHT INTO MONDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 621 PM CST MON FEB 9 2015
OVER THE NEXT 24 HOURS...EXPECT MOSTLY CLEAR SKIES AT THE KLBF AND
KVTN TERMINALS. SOME LOW CLOUDS MAY TRY TO BACK INTO THE KVTN
TERMINAL FROM THE EAST THIS EVENING AND THIS WILL BE MONITORED.
WINDS WILL BE FROM THE EAST OR SOUTHEAST THIS EVENING...SWITCHING
TO THE SOUTHWEST AND WEST OVERNIGHT TONIGHT INTO TUESDAY MORNING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM CST TUESDAY FOR NEZ006-007-009-010-
028-029.
&&
$$
UPDATE...CLB
SYNOPSIS...POWER
SHORT TERM...JACOBS
LONG TERM...POWER
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
753 PM CST MON FEB 9 2015
.SYNOPSIS...
ISSUED AT 254 PM CST MON FEB 9 2015
AT H5 TROUGH FROM GREAT LAKES INTO FLORIDA PANHANDLE WITH
ASSOCIATED PRECIPITATION ALL ALONG THE EASTERN SEABOARD. RIDGE
INTO THE NORTHERN PLAINS WITH FAIRLY STRONG WAVE MOVING ACROSS THE
PACIFIC NORTHWEST.
&&
.UPDATE...
ISSUED AT 752 PM CST MON FEB 9 2015
JUST RELEASED AN UPDATED FORECAST TO ADDRESS THE FOG AND STRATUS
ACROSS EASTERN PORTIONS OF THE FORECAST AREA. LOOKING AT THE
HRRR...LATEST NAM12 SOLN AND SREF DATA...DECIDED TO PUSH FOG
FURTHER WEST UP TO THE HIGHWAY 83 CORRIDOR THIS EVENING. THE
MODELS DO SHIFT THIS EAST OVERNIGHT AS THE LOW LEVEL WINDS SHIFT
TO THE WEST...SO FOG WILL PEAK AROUND MIDNIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 254 PM CST MON FEB 9 2015
MAIN FORECAST CONCERN FOR THE OVERNIGHT REVOLVES AROUND THE WESTWARD
RETURN OF STRATUS AND/OR FOG. THE NAM MODEL IS ONCE AGAIN THE MOST
BULLISH WITH REDUCED VISIBILITY...BRINGING DENSE FOG AS FAR WEST AS
THE HIGHWAY 83 CORRIDOR. THE HRRR SEEMS TO BE A GOOD COMPROMISE FOR
NOW...WHICH INDICATES FOG IN THE SAME GENERAL AREA AS SEEN EARLIER
TODAY. SURFACE LOW PRESSURE IS SHOWN TO MOVE EAST ACROSS SOUTHERN
SOUTH DAKOTA OVERNIGHT...DRAGGING A TROUGH THROUGH THE
SANDHILLS...SO AM EXPECTING A GREATER WESTWARD...OR
SOUTHWEST...TRAJECTORY OF THE LOWER TROPOSPHERIC WIND...WHICH WILL
DRAW DRY LOW LEVEL AIR BACK INTO THE REGION. THIS BOUNDARY IS SHOWN
TO BE ALONG OR NEAR HIGHWAY 281 BY 12Z TOMORROW. FOR THIS...WOULD
EXPECT SOME IMPROVEMENT IN VISIBILITY AND SKY COVER FROM WEST TO
EAST THROUGH THE OVERNIGHT HOURS AND THE STRATUS SHOULD ONLY BE
CONFINED TO OUR FAR EAST.
A WEAK UPPER LEVEL DISTURBANCE/PV ANOMALY WILL CROSS THE
CENTRAL/NORTHERN PLAINS OVERNIGHT PROVIDING FOR A LEAST A SLIGHT
CHANCE OF PRECIPITATION ACROSS OUR FAR NORTHEAST. THE MODELS ARE
KEYING ON THE GREATEST FORCING WELL NORTH OF THE FORECAST AREA...AND
WITH SATURATION CONFINED TO THE LOWER TROPOSPHERE...RAIN WILL BE
DIFFICULT. AM LEANING TOWARD A DRIZZLE POTENTIAL...OR VERY LIGHT
RAIN...IF PRECIPITATION WERE TO BE REALIZED. ANY LIFT IS QUICKLY
EAST OF THE FORECAST AREA BY 12Z TUESDAY...BEYOND THAT...THE REST OF
THE DAY APPEARS DRY.
TEMPERATURES OVERNIGHT WILL BE MILD AS WAA SPREADS EAST AHEAD OF THE
PASSING SURFACE TROUGH. FORECAST LOWS RANGE FROM THE UPPER 20S IN
THE RIVER VALLEYS...TO THE MID 30S ACROSS THE HEART OF THE SANDHILLS
WHERE GREATER MIXING IS ANTICIPATED. FOR TUESDAY...THE DISTURBANCE
WILL DRAW SLIGHTLY COOLER AIR ACROSS WEST CENTRAL NEBRASKA. HIGHS
WERE TRENDED ACCORDINGLY...WITH MOST LOCATIONS SEEING A DROP OF 5-7F
FROM WHAT WAS OBSERVED TODAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 254 PM CST MON FEB 9 2015
MODELS IN FAIR AGREEMENT IN MID TERM AND THEN HAVING SOME
VARIABILITY IN LONG TERM SOLUTIONS. TUESDAY NIGHT COOLER AIR
FILTERS IN ACROSS THE NORTHERN PLAINS INTO WESTERN NEBRASKA. WITH
THE UPPER RIDGE IN PLACE THE HIGH PRESSURE WILL BE MOVED FURTHER
EAST WITH A STATIONARY BOUNDARY FROM THE NORTHERN NEBRASKA
PANHANDLE INTO BROKEN BOW. WARMER 40S TO THE SOUTHWEST AND 30S TO
THE NORTHEAST. LOWS WEDNESDAY NIGHT QUITE COLD WITH MOSTLY CLEAR
SKIES AND LIGHT WINDS. SINGLE DIGITS ONEILL AND LOW 20S OVER
SOUTHWEST NEBRASKA. SOUTHERLY WINDS THURSDAY WILL MODERATE
TEMPERATURES SOME WHAT ON THE BACKSIDE OF THE SURFACE HIGH. MILD
NIGHT THURSDAY NIGHT WITH RETURN FLOW. FRIDAY TEMPERATURES REBOUND
INTO THE 40S NORTH AND 50S SOUTH. A DRY BACKDOOR COLD FRONT WILL
MOVE ACROSS THE FORECAST AREA FRIDAY NIGHT INTO SATURDAY WITH
HIGHS ON SATURDAY RANGING FROM THE 20S ONEILL TO MID 40S IMPERIAL.
TEMPERATURES REBOUND SUNDAY WITH 40S NORTH AND 50S SOUTH IN RETURN
FLOW. INCREASING MOISTURE ACROSS THE SOUTHERN PLAINS SUNDAY AND AN
ARCTIC COLD FRONT MOVING SOUTH ACROSS THE NORTHERN PLAINS WILL SEE
A RETURN TO SNOW IN THE FORECAST SUNDAY NIGHT INTO MONDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 621 PM CST MON FEB 9 2015
OVER THE NEXT 24 HOURS...EXPECT MOSTLY CLEAR SKIES AT THE KLBF AND
KVTN TERMINALS. SOME LOW CLOUDS MAY TRY TO BACK INTO THE KVTN
TERMINAL FROM THE EAST THIS EVENING AND THIS WILL BE MONITORED.
WINDS WILL BE FROM THE EAST OR SOUTHEAST THIS EVENING...SWITCHING
TO THE SOUTHWEST AND WEST OVERNIGHT TONIGHT INTO TUESDAY MORNING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CLB
SYNOPSIS...POWER
SHORT TERM...JACOBS
LONG TERM...POWER
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
621 PM CST MON FEB 9 2015
.SYNOPSIS...
ISSUED AT 254 PM CST MON FEB 9 2015
AT H5 TROUGH FROM GREAT LAKES INTO FLORIDA PANHANDLE WITH
ASSOCIATED PRECIPITATION ALL ALONG THE EASTERN SEABOARD. RIDGE
INTO THE NORTHERN PLAINS WITH FAIRLY STRONG WAVE MOVING ACROSS THE
PACIFIC NORTHWEST.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 254 PM CST MON FEB 9 2015
MAIN FORECAST CONCERN FOR THE OVERNIGHT REVOLVES AROUND THE WESTWARD
RETURN OF STRATUS AND/OR FOG. THE NAM MODEL IS ONCE AGAIN THE MOST
BULLISH WITH REDUCED VISIBILITY...BRINGING DENSE FOG AS FAR WEST AS
THE HIGHWAY 83 CORRIDOR. THE HRRR SEEMS TO BE A GOOD COMPROMISE FOR
NOW...WHICH INDICATES FOG IN THE SAME GENERAL AREA AS SEEN EARLIER
TODAY. SURFACE LOW PRESSURE IS SHOWN TO MOVE EAST ACROSS SOUTHERN
SOUTH DAKOTA OVERNIGHT...DRAGGING A TROUGH THROUGH THE
SANDHILLS...SO AM EXPECTING A GREATER WESTWARD...OR
SOUTHWEST...TRAJECTORY OF THE LOWER TROPOSPHERIC WIND...WHICH WILL
DRAW DRY LOW LEVEL AIR BACK INTO THE REGION. THIS BOUNDARY IS SHOWN
TO BE ALONG OR NEAR HIGHWAY 281 BY 12Z TOMORROW. FOR THIS...WOULD
EXPECT SOME IMPROVEMENT IN VISIBILITY AND SKY COVER FROM WEST TO
EAST THROUGH THE OVERNIGHT HOURS AND THE STRATUS SHOULD ONLY BE
CONFINED TO OUR FAR EAST.
A WEAK UPPER LEVEL DISTURBANCE/PV ANOMALY WILL CROSS THE
CENTRAL/NORTHERN PLAINS OVERNIGHT PROVIDING FOR A LEAST A SLIGHT
CHANCE OF PRECIPITATION ACROSS OUR FAR NORTHEAST. THE MODELS ARE
KEYING ON THE GREATEST FORCING WELL NORTH OF THE FORECAST AREA...AND
WITH SATURATION CONFINED TO THE LOWER TROPOSPHERE...RAIN WILL BE
DIFFICULT. AM LEANING TOWARD A DRIZZLE POTENTIAL...OR VERY LIGHT
RAIN...IF PRECIPITATION WERE TO BE REALIZED. ANY LIFT IS QUICKLY
EAST OF THE FORECAST AREA BY 12Z TUESDAY...BEYOND THAT...THE REST OF
THE DAY APPEARS DRY.
TEMPERATURES OVERNIGHT WILL BE MILD AS WAA SPREADS EAST AHEAD OF THE
PASSING SURFACE TROUGH. FORECAST LOWS RANGE FROM THE UPPER 20S IN
THE RIVER VALLEYS...TO THE MID 30S ACROSS THE HEART OF THE SANDHILLS
WHERE GREATER MIXING IS ANTICIPATED. FOR TUESDAY...THE DISTURBANCE
WILL DRAW SLIGHTLY COOLER AIR ACROSS WEST CENTRAL NEBRASKA. HIGHS
WERE TRENDED ACCORDINGLY...WITH MOST LOCATIONS SEEING A DROP OF 5-7F
FROM WHAT WAS OBSERVED TODAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 254 PM CST MON FEB 9 2015
MODELS IN FAIR AGREEMENT IN MID TERM AND THEN HAVING SOME
VARIABILITY IN LONG TERM SOLUTIONS. TUESDAY NIGHT COOLER AIR
FILTERS IN ACROSS THE NORTHERN PLAINS INTO WESTERN NEBRASKA. WITH
THE UPPER RIDGE IN PLACE THE HIGH PRESSURE WILL BE MOVED FURTHER
EAST WITH A STATIONARY BOUNDARY FROM THE NORTHERN NEBRASKA
PANHANDLE INTO BROKEN BOW. WARMER 40S TO THE SOUTHWEST AND 30S TO
THE NORTHEAST. LOWS WEDNESDAY NIGHT QUITE COLD WITH MOSTLY CLEAR
SKIES AND LIGHT WINDS. SINGLE DIGITS ONEILL AND LOW 20S OVER
SOUTHWEST NEBRASKA. SOUTHERLY WINDS THURSDAY WILL MODERATE
TEMPERATURES SOME WHAT ON THE BACKSIDE OF THE SURFACE HIGH. MILD
NIGHT THURSDAY NIGHT WITH RETURN FLOW. FRIDAY TEMPERATURES REBOUND
INTO THE 40S NORTH AND 50S SOUTH. A DRY BACKDOOR COLD FRONT WILL
MOVE ACROSS THE FORECAST AREA FRIDAY NIGHT INTO SATURDAY WITH
HIGHS ON SATURDAY RANGING FROM THE 20S ONEILL TO MID 40S IMPERIAL.
TEMPERATURES REBOUND SUNDAY WITH 40S NORTH AND 50S SOUTH IN RETURN
FLOW. INCREASING MOISTURE ACROSS THE SOUTHERN PLAINS SUNDAY AND AN
ARCTIC COLD FRONT MOVING SOUTH ACROSS THE NORTHERN PLAINS WILL SEE
A RETURN TO SNOW IN THE FORECAST SUNDAY NIGHT INTO MONDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 621 PM CST MON FEB 9 2015
OVER THE NEXT 24 HOURS...EXPECT MOSTLY CLEAR SKIES AT THE KLBF AND
KVTN TERMINALS. SOME LOW CLOUDS MAY TRY TO BACK INTO THE KVTN
TERMINAL FROM THE EAST THIS EVENING AND THIS WILL BE MONITORED.
WINDS WILL BE FROM THE EAST OR SOUTHEAST THIS EVENING...SWITCHING
TO THE SOUTHWEST AND WEST OVERNIGHT TONIGHT INTO TUESDAY MORNING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...POWER
SHORT TERM...JACOBS
LONG TERM...POWER
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
1004 PM PST SAT FEB 7 2015
.SYNOPSIS...WARM SPRING LIKE CONDITIONS WILL CONTINUE SUNDAY AND
MONDAY FOR MUCH OF THE AREA UNDER A DRY...SOUTHWEST FLOW. HIGH
TEMPERATURES ARE EXPECTED TO APPROACH RECORD LEVELS IN SOME AREAS
BOTH DAYS. A PACIFIC STORM WILL IMPACT THE NORTHWESTERN REGIONS OF
THE FORECAST AREA LATE SUNDAY AND SUNDAY NIGHT WITH ANOTHER ROUND OF
RAIN AND HIGH ELEVATION SNOW OVER THE SIERRA AND OWENS VALLEY.
&&
.UPDATE...FOG HAS DEVELOPED IN THE OWENS VALLEY PER THE LATEST
OBSERVATIONS AT BISHOP AND THE VISIBILITY AT THE EASTERN SIERRA
REGIONAL AIRPORT QUICKLY TANKED TO 1/2 MILE. AREAS OF FOG WERE ADDED
IN FOR THE REST OF TONIGHT TO THE OWENS VALLEY AS WELL AS THE
EASTERN SLOPES OF THE SOUTHERN SIERRA NEVADA AND THE WHITE
MOUNTAINS.
&&
.PREVIOUS UPDATE...
ISSUED AT 915 PM PST SAT FEB 7 2015
.UPDATE...THE MODELS DID A HORRIBLE JOB HANDLING THE INFLUX OF
MOISTURE INTO THE MOJAVE DESERT THIS EVENING AND THE LIGHT
SHOWERS/SPRINKLES THAT DID MATERIALIZE AS A RESULT. THE EVENING
SOUNDING FROM OUR OFFICE CAME IN WITH A VERY MOIST PWAT OF 0.77 INCH
FOR JANUARY WHICH WAS UP CONSIDERABLY FROM THE 0.29 INCH REGISTERED
ON THIS MORNING`S SOUNDING. THE HRRR APPEARS TO HAVE SOME CLUE AS TO
WHAT IS ACTUALLY GOING ON AND AS A RESULT BASED ON THIS AND THE
LATEST RADAR RETURNS, I HAVE UPDATED THE FORECAST TO ADD IN LIGHT
SHOWERS OVER NORTHERN MOHAVE COUNTY FOR THE REST OF THE NIGHT
ALTHOUGH LIKELY THESE SHOULD FIZZLE OUT BY 2-4 AM - IF NOT EARLIER.
ELSEWHERE CHANGES INCLUDED TWEAKING SKY COVER TO ADD INTO ADDITIONAL
CLOUDS OVER THE EAST-CENTRAL PART OF THE AREA AND ADJUSTING UP
DEWPOINTS WHICH HAVE COME UP QUITE A BIT. I AM A LITTLE CONCERNED
GIVEN THE AMOUNT OF MOISTURE AROUND AND EVEN WINDS STIRRING THINGS
UP THAT WE MAY STILL BE TOO COOL FOR LOWS TONIGHT AND I DID GO AHEAD
AND ADJUST THEM UP. OF FURTHER FOCUS FOR THE REST OF TONIGHT WILL BE
HOW WARM TO GO WITH TEMPS ON SUNDAY FOLLOWING TODAY`S RECORD WARMTH
IN A FEW SPOTS AND THE FACT THAT WE ARE NOT GOING TO COOL OFF ALL
THAT MUCH OVERNIGHT NOR LOOSE THE MOISTURE THAT WORKED ON IN.
HOWEVER, I WILL HOLD OFF ON ANY CHANGES WITH THAT FOR THE EARLY
MORNING PACKAGE.
&&
.AVIATION...FOR MCCARRAN...WINDS WILL TREND TOWARD TYPICAL DIURNAL
DIRECTIONS THROUGH SUNDAY EVENING AT 12 KTS OR LESS. SCT-BKN CLOUDS
AOA 10K-12K FEET.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...CIGS AS LOW AS 5K FEET OR SO ARE EXPECTED IN AND AROUND
KBIH. ALTHOUGH SHRA- CANNOT BE RULED OUT AT KBIH, THE BETTER CHANCE
FOR SHOWERS WILL BE OVER THE SOUTHERN SIERRA ESPECIALLY TOWARD THE
CREST. MOUNTAIN OBSCURATIONS ARE EXPECTED IN THIS AREA. ELSEWHERE
WINDS SHOULD FAVOR TYPICAL DIURNAL TRENDS WITH SCT-BKN CLOUDS AOA
10-12K FEET. A FEW AREAS IN NORTHERN MOHAVE AND NORTHEAST CLARK
COUNTIES MAY SEE A BRIEF SHRA- THROUGH 10Z SUNDAY.
&&
.PREVIOUS DISCUSSION...
217 PM PST SAT FEB 7 2015
.DISCUSSION...SHORTWAVE ENERGY ASSOCIATED WITH ANOTHER PACIFIC LOW
PRESSURE SYSTEM WILL MOVE INTO CENTRAL AND NORTHERN CALIFORNIA LATE
SUNDAY AND THEN WEAKEN AS IT CROSSES THE SIERRA AND MOVES INTO THE
SOUTHERN GREAT BASIN SUNDAY NIGHT INTO MONDAY. THIS SYSTEM WILL
BRING MORE RAIN AND HIGH ELEVATION SNOW TO THE SIERRA BY LATE SUNDAY
AFTERNOON WITH RAIN SHOWERS SPILLING OVER INTO THE OWENS VALLEY
SUNDAY NIGHT INTO EARLY MONDAY. A FEW SHOWERS ARE POSSIBLE MONDAY
ACROSS ESMERALDA, CENTRAL NYE AND NORTHERN LINCOLN COUNTIES AS THE
SHORTWAVE PASSES THROUGH THE GREAT BASIN.
AS THE SHORTWAVE MOVES EAST OF THE AREA, MODELS TAKE IT SOUTH
THROUGH UTAH AND ARIZONA TUESDAY INTO WEDNESDAY...DRAGGING A COLD
FRONT SOUTH THROUGH THE FORECAST AREA. THIS WILL RESULT IN SLIGHTLY
COOLER TEMPERATURES AND BREEZY TO LOCALLY WINDY CONDITIONS THAT WILL
LINGER INTO THURSDAY. THE SHORTWAVE CONTINUES TO MOVE SOUTH AND
MODELS GENERALLY AGREE A CLOSED LOW FORMS OVER NORTHERN MEXICO ON
THURSDAY. MODELS THEN TAKE IT WEST OF THE BAJA PENINSULA FRIDAY.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION IS NOT EXPECTED
BUT ANY REPORTS OF HIGH WINDS OR PRECIPITATION WOULD BE APPRECIATED.
&&
$$
UPDATE/AVIATION...STACHELSKI
PREVIOUS...SALMEN
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
915 PM PST SAT FEB 7 2015
.SYNOPSIS...WARM SPRING LIKE CONDITIONS WILL CONTINUE SUNDAY AND
MONDAY FOR MUCH OF THE AREA UNDER A DRY...SOUTHWEST FLOW. HIGH
TEMPERATURES ARE EXPECTED TO APPROACH RECORD LEVELS IN SOME AREAS
BOTH DAYS. A PACIFIC STORM WILL IMPACT THE NORTHWESTERN REGIONS OF
THE FORECAST AREA LATE SUNDAY AND SUNDAY NIGHT WITH ANOTHER ROUND OF
RAIN AND HIGH ELEVATION SNOW OVER THE SIERRA AND OWENS VALLEY.
&&
.UPDATE...THE MODELS DID A HORRIBLE JOB HANDLING THE INFLUX OF
MOISTURE INTO THE MOJAVE DESERT THIS EVENING AND THE LIGHT
SHOWERS/SPRINKLES THAT DID MATERIALIZE AS A RESULT. THE EVENING
SOUNDING FROM OUR OFFICE CAME IN WITH A VERY MOIST PWAT OF 0.77 INCH
FOR JANUARY WHICH WAS UP CONSIDERABLY FROM THE 0.29 INCH REGISTERED
ON THIS MORNING`S SOUNDING. THE HRRR APPEARS TO HAVE SOME CLUE AS TO
WHAT IS ACTUALLY GOING ON AND AS A RESULT BASED ON THIS AND THE
LATEST RADAR RETURNS, I HAVE UPDATED THE FORECAST TO ADD IN LIGHT
SHOWERS OVER NORTHERN MOHAVE COUNTY FOR THE REST OF THE NIGHT
ALTHOUGH LIKELY THESE SHOULD FIZZLE OUT BY 2-4 AM - IF NOT EARLIER.
ELSEWHERE CHANGES INCLUDED TWEAKING SKY COVER TO ADD INTO ADDITIONAL
CLOUDS OVER THE EAST-CENTRAL PART OF THE AREA AND ADJUSTING UP
DEWPOINTS WHICH HAVE COME UP QUITE A BIT. I AM A LITTLE CONCERNED
GIVEN THE AMOUNT OF MOISTURE AROUND AND EVEN WINDS STIRRING THINGS
UP THAT WE MAY STILL BE TOO COOL FOR LOWS TONIGHT AND I DID GO AHEAD
AND ADJUST THEM UP. OF FURTHER FOCUS FOR THE REST OF TONIGHT WILL BE
HOW WARM TO GO WITH TEMPS ON SUNDAY FOLLOWING TODAY`S RECORD WARMTH
IN A FEW SPOTS AND THE FACT THAT WE ARE NOT GOING TO COOL OFF ALL
THAT MUCH OVERNIGHT NOR LOOSE THE MOISTURE THAT WORKED ON IN.
HOWEVER, I WILL HOLD OFF ON ANY CHANGES WITH THAT FOR THE EARLY
MORNING PACKAGE.
&&
.AVIATION...FOR MCCARRAN...WINDS WILL TREND TOWARD TYPICAL DIURNAL
DIRECTIONS THROUGH SUNDAY EVENING AT 12 KTS OR LESS. SCT-BKN CLOUDS
AOA 10K-12K FEET.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...CIGS AS LOW AS 5K FEET OR SO ARE EXPECTED IN AND AROUND
KBIH. ALTHOUGH SHRA- CANNOT BE RULED OUT AT KBIH, THE BETTER CHANCE
FOR SHOWERS WILL BE OVER THE SOUTHERN SIERRA ESPECIALLY TOWARD THE
CREST. MOUNTAIN OBSCURATIONS ARE EXPECTED IN THIS AREA. ELSEWHERE
WINDS SHOULD FAVOR TYPICAL DIURNAL TRENDS WITH SCT-BKN CLOUDS AOA
10-12K FEET. A FEW AREAS IN NORTHERN MOHAVE AND NORTHEAST CLARK
COUNTIES MAY SEE A BRIEF SHRA- THROUGH 10Z SUNDAY.
&&
.PREVIOUS DISCUSSION...
217 PM PST SAT FEB 7 2015
.DISCUSSION...SHORTWAVE ENERGY ASSOCIATED WITH ANOTHER PACIFIC LOW
PRESSURE SYSTEM WILL MOVE INTO CENTRAL AND NORTHERN CALIFORNIA LATE
SUNDAY AND THEN WEAKEN AS IT CROSSES THE SIERRA AND MOVES INTO THE
SOUTHERN GREAT BASIN SUNDAY NIGHT INTO MONDAY. THIS SYSTEM WILL
BRING MORE RAIN AND HIGH ELEVATION SNOW TO THE SIERRA BY LATE SUNDAY
AFTERNOON WITH RAIN SHOWERS SPILLING OVER INTO THE OWENS VALLEY
SUNDAY NIGHT INTO EARLY MONDAY. A FEW SHOWERS ARE POSSIBLE MONDAY
ACROSS ESMERALDA, CENTRAL NYE AND NORTHERN LINCOLN COUNTIES AS THE
SHORTWAVE PASSES THROUGH THE GREAT BASIN.
AS THE SHORTWAVE MOVES EAST OF THE AREA, MODELS TAKE IT SOUTH
THROUGH UTAH AND ARIZONA TUESDAY INTO WEDNESDAY...DRAGGING A COLD
FRONT SOUTH THROUGH THE FORECAST AREA. THIS WILL RESULT IN SLIGHTLY
COOLER TEMPERATURES AND BREEZY TO LOCALLY WINDY CONDITIONS THAT WILL
LINGER INTO THURSDAY. THE SHORTWAVE CONTINUES TO MOVE SOUTH AND
MODELS GENERALLY AGREE A CLOSED LOW FORMS OVER NORTHERN MEXICO ON
THURSDAY. MODELS THEN TAKE IT WEST OF THE BAJA PENINSULA FRIDAY.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION IS NOT EXPECTED
BUT ANY REPORTS OF HIGH WINDS OR PRECIPITATION WOULD BE APPRECIATED.
&&
$$
UPDATE/AVIATION...STACHELSKI
PREVIOUS...SALMEN
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
254 PM EST SUN FEB 8 2015
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL MOVE EAST ALONG A FRONT DRAPED OVER THE
AREA BRINGING A MIX OF PRECIPITATION TO THE AREA THROUGH EARLY TONIGHT.
COLDER AIR WILL MOVE INTO THE AREA OVERNIGHT, CHANGING THE WINTRY
MIX TO ALL SNOW, FROM NORTH TO SOUTH. THE SNOW WILL DIMINISH BY
MONDAY NIGHT. DRY BUT COLDER WEATHER BUILDS IN FOR TUESDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
230 PM UPDATE...
AS COMPLEX AS THIS FORECAST IS, FROM A METEOROLOGICAL PERSPECTIVE
IT IS BEAUTIFUL TO WATCH. RIGHT NOW WE HAVE AN EXTREME THERMAL GRADIENT
ACROSS THE AREA. THE CENTRAL AND SOUTHERN PART OF THE FORECAST AREA
IS SITTING IN THE MIDDLE 30S TO NEAR 40, WHILE SYRACUSE IS STILL
JUST 19. YOU WANT TO TALK EXTREMES. ITHACA HAS DROPPED TO 27 OVER
THE PAST FEW HOURS WHILE JUST EAST AT CORTLAND IT IS STILL 37!
ALONG AND JUST NORTH OF THIS GRADIENT AN EAST/WEST AXIS OF
PRECIPITATION HAS BROKEN OUT FROM SOUTHERN ONTARIO EAST THROUGH
CENTRAL NEW YORK. GRADUALLY THROUGH EARLY EVENING THIS AREA OF
PRECIPITATION WILL EXPAND. AT FIRST THE THERMAL GRADIENT WON`T
MOVE MUCH, SO THE MAIN FOCUS OF PRECIPITATION WILL BE WHERE IT IS
NOW OR MAINLY ACROSS CENTRAL NEW YORK WITH LITTLE TO NO
PRECIPITATION FARTHER SOUTH.
LATER THIS EVENING AS THE BOUNDARY SLOWLY, SLOWLY SLIDES SOUTH,
OUR TEMPS WILL COOL AND THE EXPANDING AREA OF PRECIPITATION WILL
ALSO EXPAND SOUTHWARD. I THREW OUT THE MUCH WARMER 12Z GFS AS IT
IS ALREADY TOO WARM WITH 850 TEMPS OF +2C WHERE CURRENT MESO
ANALYSIS SHOWS 850 TEMPS CLOSER TO 0C OR -1C. IN FACT WHILE THE
12Z NAM AND 12Z EURO ARE THE CLOSEST MODELS TO REALITY AT 850 MB,
CURRENT ANALYSIS SHOWS THEY ARE EVEN RUNNING A TAD WARM AT THAT
LEVEL. FOLLOWING THE NAM AND RUC MODEL SOUNDINGS, AND LOOKING AT
THE LOW LEVEL DRY AIR WE HAVE IN PLACE, WET BULBING AS
PRECIPITATION EXPANDS THIS EVENING WILL LIKELY COOL THE COLUMN
ENOUGH TO CHANGE US OVER TO SNOW FROM NORTH TO SOUTH. DURING THE
TRANSITION A PERIOD OF SLEET OR FREEZING RAIN IS POSSIBLE.
ACROSS NY STATE, PRETTY MUCH ALL SNOW IS EXPECTED NORTH OF A
CORTLAND TO NORWICH LINE. ACROSS THE SOUTHERN TIER OF NY A WINTRY
MIX IS POSSIBLE AT THE ONSET, AND SURFACE TEMPS SUPPORT JUST RAIN
IN THE VALLEYS NEAR GREATER BINGHAMTON. EVEN HERE HOWEVER, COOLING
OF THE COLUMN WILL CHANGE US OVER TO ALL SNOW TOWARD 03Z/04Z AS
PRECIPITATION BECOMES STEADIER. A LIGHT COATING OF ICE IS POSSIBLE
PRIOR TO THE TRANSITION TO ALL SNOW, BUT ICE AMOUNTS ARE NOT
EXPECTED TO BE SIGNIFICANT IN NY STATE. TOTAL SNOW AMOUNTS WILL RANGE
FROM 8" TO 12" ACROSS CENTRAL NY AND THE CATSKILLS WHERE WE STAY
ALL SNOW. 5" TO 10" FROM THE FINGER LAKES DOWN THROUGH THE
SOUTHERN TIER WHERE MIXING IS A CONCERN. IN THE 5" TO 10" AREA,
THE HIGHER AMOUNTS WILL OCCUR IN THE FINGER LAKES, WITH THE LOWER
AMOUNTS NEAR THE NY/PA LINE.
ACROSS NORTHERN PA, THE TRANSITION PROCESS TO A WINTRY MIX AND
EVENTUALLY ALL SNOW WILL BE MUCH, MUCH SLOWER. THIS WILL BE ESPECIALLY
TRUE IN THE WILKES-BARRE/SCRANTON AREA. WHILE WE MAY SEE A WINTRY
MIX EARLY IN THE EVENING ACROSS THE NORTHERN TIER AND NORMALLY
COLDER SPOTS OF PIKE/WAYNE COUNTIES, THE WYOMING VALLEY SHOULD NOT
SEE ANY CHANGEOVER UNTIL AFTER MIDNIGHT. HERE WE DO NOT EXPECT A
CHANGE TO ALL SNOW UNTIL CLOSER TO MID MONDAY MORNING. DUE TO THE
PROLONGED PERIOD OF SLEET AND/OR FREEZING RAIN, ICE AMOUNTS ARE
EXPECTED TO BE MORE SIGNIFICANT, AND SNOW AMOUNTS LESS SO. ICE
AMOUNTS BETWEEN A TENTH AND TWO TENTHS ARE LIKELY, WITH SNOW
GENERALLY IN THE 3" TO 6" RANGE. THE HIGHEST SNOW AMOUNTS WILL BE
NEAR THE NY/PA LINE. CURRENT ADVISORY AND WARNING IN GOOD SHAPE
WITH MINOR SNOW ADJUSTMENTS TO REFLECT LATEST TRENDS OF SLIGHTLY
LESS SNOW FROM NEAR THE NY/PA LINE SOUTHWARD.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
245 PM UPDATE...
MONDAY NIGHT/TUESDAY...DRYING IN THE -10C TO -20C LAYER MONDAY
NIGHT WILL MEAN AN END TO PRECIPITATION FROM WEST TO EAST. SINCE
WE STILL HAVE A BIT OF MOISTURE BUT NOT MUCH IN THE IDEAL SNOW
GROWTH REGION, IN INCLUDED A MENTION OF FREEZING DRIZZLE/FLURRIES
WHERE CHANCES FOR PRECIPITATION DROP BELOW 60%. DRIER WEATHER
BUILDS IN FOR TUESDAY.
TUESDAY NIGHT...SFC HIGH PRES OVER EASTERN CANADA WILL PROVIDE A
MAINLY CLEAR AND COLD NIGHT. LOWS WILL GENERALLY RANGE IN THE SINGLE
NUMBERS WITH READINGS AROUND 10 ACROSS THE FAR SE.
WEDNESDAY...A CLIPPER LOW WILL MOVE THROUGH THE NORTHERN GREAT LAKES
AND BRING A CHANCE FOR LIGHT SNOW DURING THE AFTERNOON ACROSS MUCH
OF CENTRAL NEW YORK. WILL CONTINUE WITH A DRY FORECAST FOR NE PA AS
BEST MOISTURE AND LIFT WILL RESIDE OVER THE NRN CWA. BRIEF WARMUP
AHEAD OF THIS SYSTEM WILL ALLOW TEMPS TO RISE INTO THE MID/UPPER 20S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
EXTENDED FORECAST PERIOD WILL BE DOMINATED BY AN UPPER LEVEL TROF
OVER THE EASTERN UNITED STATES WHICH WILL KEEP TEMPERATURES WELL
BELOW NORMAL THROUGH THE PERIOD.
WEDNESDAY NIGHT INTO THURSDAY A CLIPPER SFC LOW WILL TRACK THROUGH
THE SOUTHERN GREAT LAKES THEN EASTWARD THROUGH PA. THIS FEATURE
WILL BRING LIGHT SNOW ACCUMS TO THE REGION, GENERALLY LESS THAN
THREE INCHES. ONCE THIS WAVE PASSES ANOTHER SHOT OF ARCTIC AIR
WILL OVERSPREAD THE REGION AND PERSIST THROUGH THE WEEKEND. TEMPS
THURSDAY NIGHT THROUGH SATURDAY WILL RUN 15 TO 25 DEGREES BELOW
NORMAL. ANOTHER WEAK CLIPPER TYPE LOW MAY IMPACT THE AREA SATURDAY
INTO SATURDAY NIGHT.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
A FRONTAL BOUNDARY CURRENTLY DRAPED ACROSS THE REGION AND AN AREA
OF LOW PRES WHICH WILL TRACK ACROSS THE MID ATLANTIC REGION LATER
TONIGHT AND MONDAY WILL BRING IFR/BELOW ALT MIN CONDITIONS TO THE
TERMINALS LATE THIS AFTERNOON THROUGH END OF TAF PERIOD.
AT KRME/KSYR/KITH, IFR SNOW WILL BEGIN BETWEEN 19Z-22Z. AFTER 22Z
CONDITIONS WILL BE BELOW ALT MINS DUE TO SNOW THROUGH END OF TAF
PERIOD.
AT KELM, AN MVFR RAIN/SNOW MIX WILL BEGIN BETWEEN 21Z-24Z. AFTER
00Z IFR WITH PRECIP A MIX OF FZRA/SN, AFTER 03Z JUST SNOW WITH
CONDITIONS BELOW ALT MINS.
AT KBGM, PRECIP WILL START BETWEEN 21Z-24Z AS A MIX OF SLEET AND
SNOW, AFTER 00Z PRIMARILY JUST IFR SNOW THEN AFTER 04Z CONTINUED
SNOW WITH CONDITIONS BELOW ALT MINS.
AT KAVP, VFR THROUGH 00Z THEN MVFR CONDITIONS IN LIGHT RAIN THEN
AFTER 06Z IFR WITH A MIX OF FZRA AND SLEET AFTER 15Z PRECIP WILL
LIKELY CHANGE TO SNOW WITH CONDITIONS BELOW ALT MINS.
WINDS OVERNIGHT EITHER EAST AROUND 5 KNOTS OR LIGHT AND VARIABLE NIGHT.
OUTLOOK...
MON NIGHT/TUE...MAINLY VFR.
WED/WED NGT...RESTRICTIONS POSSIBLE AREA-WIDE FROM LIGHT SNOW.
THU/FRI...RESTRICTIONS POSSIBLE AT THE CNY TERMINALS FROM SNOW
SHWRS...WITH MAINLY VFR EXPECTED AT KAVP.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 1 AM EST
TUESDAY FOR PAZ038>040-043-044-047-048-072.
NY...WINTER STORM WARNING UNTIL 7 AM EST TUESDAY FOR NYZ009-015>018-
022>025-036-037-044>046-055>057-062.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN
SHORT TERM...HEDEN/RRM
LONG TERM...RRM
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
850 PM EST MON FEB 9 2015
.SYNOPSIS...
SHOWERS DEVELOPING INLAND THIS AFTERNOON WILL SPREAD TO THE COAST
TONIGHT. A COLD FRONT WILL MOVE OFFSHORE EARLY TUESDAY MORNING
WITH MUCH COLDER TEMPERATURES TUESDAY AND WEDNESDAY. SEASONABLE
WEATHER WILL RETURN THURSDAY...BEFORE AN ARCTIC COLD FRONT CROSSES
THE AREA THURSDAY NIGHT. DRY BUT VERY COLD WEATHER WILL BECOME
ENTRENCHED FRIDAY THROUGH THE UPCOMING WEEKEND AND START OF NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 745 PM MONDAY...POPS ACROSS THE FA WERE RE-ARRANGED TO
ACCOUNT FOR THE SLOW EASTWARD PROGRESSION OF THE MAIN PCPN
SHIELD. HAVE INCLUDED ISOLATED THUNDER TIL MIDNIGHT...ASSOCIATED
WITH THE LEADING EDGE OF THE PCPN AS IT TRACKS EASTWARD DUE TO
WEAK LOW LEVEL CAPE VIA LATEST HRRR MODEL RUNS. THE CENTER OF THE
SFC LOW VIA RADAR LOOPS...IS CURRENTLY OVER DARLINGTON AND
FLORENCE COUNTIES OF SC. LOOK FOR ITS EASTWARD PROGRESSION TO
CONTINUE THIS EVENING...TO JUST OFF THE CAPE FEAR COAST LATE IN
THE PRE-DAWN TUE HOURS. BY DAYBREAK TUE...MODELS INDICATE THE LOW
WILL BE INTENSIFYING AT A DECENT CLIP AS IT CONTINUES TO PUSH
SLOWLY EASTWARD...TO THE OFFSHORE WATERS EAST OF CAPE FEAR.
BEHIND THE LOW...INCREASING SFC NW-N CAA WINDS WILL OVERSPREAD THE
FA MAINLY DURING THE MID TO LATE PRE-DAWN TUE HOURS. TONIGHTS
LOWS MAY ACTUALLY OCCUR DURING DAYLIGHT TUE MORNING...DEPENDING
HOW MUCH COLD AIR INFILTRATES THE FA.
PREVIOUS DISCUSSION...................................
AS OF 3 PM MONDAY...MEASURABLE RAINFALL COVERED THE WESTERN
CAROLINAS THIS AFTERNOON AND WAS DRAWING CLOSER TO THE CENTRAL
PORTIONS OF THE STATES...ASSOCIATED WITH AN ENERGETIC SHORTWAVE
PLUGGING THROUGH GEORGIA PRESENTLY. CONVECTIVE ELEMENTS EMBEDDED
WITHIN THE RAIN AREA WERE TAKING SHAPE ACROSS CENTRAL SC AND MAY
BECOME PLAYERS ALONG AND WEST OF THE I-95 CORRIDOR INTO THE LATE
AFTERNOON. ISOLATED THUNDERSTORMS WILL BE RETAINED FOR THE NEAR
TERM FORECAST WITH A CATEGORICAL TO HIGHLY LIKELY OVERALL POP
DISTRIBUTION. SEVERE THREAT REMAINS LOW WITH GENERALLY ANEMIC WIND
SPEEDS IN THE LOW AND MID-LEVEL TROPOSPHERE PRECEDING THE FRONT.
GUSTS TO 40 KT HOWEVER CANNOT BE RULED OUT IN THE STRONGER CELLS.
LATEST SATELLITE DERIVED TOTAL PRECIPITABLE WATERS ANIMATIONS
SHOW 1 INCH WELLING NORTH-NORTHEAST INTO SC...AND LATEST WPC QPF
DEPICTIONS POINT TO 0.25-.075 INCH AVERAGES ACROSS NE SC AND SE
NC THROUGH 12Z TUESDAY. WITH CONVECTIVE INFLUENCES VARIATIONS TO
THESE BASIN AVERAGES CAN BE EXPECTED.
COLD AIR ADVECTION WILL ARRIVE LATE IN THE NEAR TERM PERIOD SO
MINIMUMS WITH CLOUD COVER AND WIND ARE APT TO DIP ONLY INTO THE
LOW 40S ACROSS INTERIOR SE NC AND MIDDLE AND UPPER 40S ELSEWHERE.
LOWS AROUND 50 ALONG AREA BEACHES BY FIRST LIGHT TUESDAY EXPECTED.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY...IMPRESSIVE SHORTWAVE OVERHEAD TUE MORNING
WILL MOVE OFF THE COAST DURING THE DAY...BECOMING NEARLY CUTOFF AT
5H AS IT DOES. MID LEVEL AMPLIFICATION SLOWS THE SYSTEM
DOWN...WITH CLOUD COVER AND PRECIP NOW LINGERING OVER THE REGION
INTO TUE AFTERNOON...ESPECIALLY ALONG THE COAST. UNDERNEATH THE 5H
TROUGH THE SURFACE LOW WILL STRENGTHEN...ENHANCING LOW LEVEL WIND
FIELD AND COLD ADVECTION. IMPRESSIVE 110KT+ 300 MB JET PASSING
SOUTH OF THE AREA TUE COMBINED WITH DEEPER WRAP AROUND MOISTURE
AND STEEP MID LEVEL LAPSE RATES MAY CONTRIBUTE TO SHOWERS DURING
THE FIRST HALF OF TUE. WILL BUMP UP INHERITED POP TO HIGH CHC
ALONG THE NC COAST TAPERING TO SLIGHT CHC FOR FAR SOUTHWESTERN
AREAS THROUGH MIDDAY. BOTH MOISTURE AND MID LEVEL INSTABILITY
DECREASE TUE AFTERNOON BUT WILL HOLD ONTO SLIGHT CHC POP ALONG THE
NC COAST INTO TUE EVENING GIVEN THE PROXIMITY TO THE STACKED LOW
JUST OFF THE COAST. INCOMING AIR MASS IS NOT PARTICULARLY COLD BUT
THE STRENGTH OF THE NORTHERLY FLOW AND CLOUD COVER WILL MAXIMIZE
THE COLD AIR AND KEEP TEMPS BELOW CLIMO. NORTHERLY FLOW CONTINUES
TUE NIGHT KEEPING LOWS NEAR TO BELOW CLIMO.
NORTHERLY FLOW WED MORNING BACKS TO WEST-NORTHWEST AS THE LOW OFF
THE COAST MOVES AWAY FROM THE AREA. WESTERLY FLOW ALOFT AND LOW
LEVEL NORTHWEST FLOW WILL RESULT IN SOME DOWNSLOPE COMPONENT BUT
LIMITED WARMING WED WILL BE MORE DUE TO AIR MASS MODIFICATION UNDER
SUNNY SKIES. SOUTHERN EXTENT OF THE SURFACE HIGH MOVES EAST OF THE
AREA LATER WED INTO WED NIGHT WITH LIGHT RETURN FLOW DEVELOPING.
TEMPERATURES WILL REMAIN BELOW CLIMO WED AND WED NIGHT.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 3 PM MONDAY...
EXTREME COLD ON THE WAY LATE IN THE PERIOD...
THURSDAY WILL BE ONE LAST MILD DAY THANKS TO SOUTHWESTERLY FLOW
AHEAD OF AN ARCTIC COLD FRONT THAT ARRIVES LATE IN THE DAY. ITS
PASSAGE WILL BE MOISTURE-STARVED IN THE LOW LEVELS. THE GFS HAS A
RELATIVELY NEW IDEA IN THAT THE MID LEVEL VORT IS STRONG ENOUGH
(36S-1) THAT A LITTLE QPF IS WRUNG OUT OVER NC ZONES POSSIBLY AFTER
TEMPS GET BELOW PTYPE THRESHOLDS. THE EURO IS NOT AS STRONG OR FAR
SOUTH WITH THE VORT CENTER AND SHOWS A MORE BELIEVABLE
NON-MEASURABLE QPF FORECAST JUST GLANCING CAPE FEAR REGION. WILL
LEAVE FORECAST DRY. THE COLD THAT FOLLOWS WILL BE THE REAL NEWS
ANYWAY. TEMPS DROP INTO THE 20S THURSDAY NIGHT AND WILL BE HARD
PRESSED TO TOP 40 ON FRIDAY. THERE WILL BE SOME SMALL RECOVERY ON
SATURDAY SINCE THE LOW LEVEL WINDS WILL BACK AHEAD OF THE NEXT
APPROACHING VORT CENTER. THIS WILL BE SHORT LIVED HOWEVER AS BY
SATURDAY AFTERNOON AN ARCTIC DISCHARGE INTO THE CAROLINAS GETS
UNDERWAY...THE LIKES OF WHICH IM NOT SURE I`VE EVER SEEN. THE GFS
AND ECMWF HAVE BEEN WAFFLING ON THE MAGNITUDE OF THE COLD BUT THEY
ARE COMING INTO BETTER AGREEMENT TODAY THAT 850MB TEMPS BOTTOM OUT
ON SUNDAY ANYWHERE FROM ABOUT -18C (EC) TO -21C (GFS). THIS
AIRMASS WILL BE TRAVELING OVER AMPLE SNOW COVER TO RETAIN IT PUNCH
THIS FAR SOUTH AND SUNDAY HIGHS WILL REMAIN BELOW FREEZING AND
TEENS APPEAR LIKELY SUNDAY NIGHT. MEX MOS FOR ILM SHOWS A HIGH OF
35 BUT ITS INCREASED WEIGHT TOWARDS CLIMO IS TO BLAME.
INTERESTINGLY THE 06Z MOS HAD AN INCREDIBLE 24...FOR A HIGH. THAT
COULD BE MUCH CLOSER TO REALITY. GIVEN THAT THIS AIRMASS TRAVELS
ACROSS SNOW AND MAY BE DRIVEN DOWN THE EAST OF THE MOUNTAINS THERE
MAY BE A TONGUE OF EVEN COLD AIR LIKE WHAT THE GFS SHOWED A FEW
DAYS AGO (850MB TEMPS CLOSER TO -26C). 850MB TEMPS MAY `WARM` BACK
TO 0C BEFORE MONDAY IS THROUGH.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
AS OF 00Z...AT KFLO/KLBT AN AREA OF LIGHT TO MODERATE RAIN WITH
EMBEDDED HEAVIER SHOWERS WILL AFFECT THE TERMINALS THIS EVENING.
PREDOMINATE MVFR VSBYS LIKELY WITH TEMPO IFR VSBYS IN THE HEAVIER
SHOWERS. TOWARDS MIDNIGHT Z RAIN DECREASES BUT PREDOMINATE MVFR CIGS
WILL DEVELOP AND PERSIST THROUGH THE TAF VALID PERIOD. THERE IS
MODERATE CONFIDENCE FROM 06-14Z IFR CIGS WILL OCCUR. A SECONDARY
SURGE OF COLD AIR SHOULD MOVE THROUGH BEFORE SUNRISE. THIS SHOULD
RESULT IN STRONG AND GUSTY NORTH WINDS TO DEVELOP AND COULD CAUSE
IFR CIGS TO IMPROVE TO MVFR QUICKER THAN INDICATED IN TAFS.
AT THE COASTAL TERMINALS VFR EXPECTED THROUGH EARLY THIS EVENING. AS
WINDS DECREASE BR WILL BECOME AN ISSUE LATE THIS EVENING. HAVE
INDICATE TEMPO MVFR VSBYS...ALTHOUGH IFR VSBYS COULD OCCUR AFTER 04Z
PER NAM BUFFER SOUNDINGS. IFR/LIFR CIG/VSBYS SEEM LIKELY OVERNIGHT WITH
PERIODS OF LIGHT RAIN. A SECONDARY SURGE OF COLD AIR SHOULD MOVE
THROUGH BEFORE SUNRISE. THIS SHOULD RESULT IN STRONG AND GUSTY NORTH
WINDS TO DEVELOP AND SHOULD CAUSE VSBYS TO IMPROVE TO VFR. BUT LIFR
CIGS COULD PERSIST THROUGH SUNRISE...AFTER WHICH MVFR CIGS
EXPECTED. IFR CIGS ARE INDICATED BY GFS MOS GUIDANCE THROUGH THE DAY
AT ALL COASTAL TERMINALS...BUT HAVE SIDED WITH MET GUIDANCE AS IT
AGREES WITH GFS TIME HEIGHT ANALYSIS WHICH SUGGEST THE HIGHER CIGS.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 745 PM MONDAY...THE CURRENT RATHER BROAD CENTER OF LOW
PRESSURE IS ACROSS NORTHEAST SOUTH CAROLINA. MODELS INDICATE THE
LOW WILL INTENSIFY AT A DECENT CLIP ONCE IT EMERGES OVER THE
ATLANTIC OFFSHORE WATERS OFF CAPE FEAR AROUND DAYBREAK TUE. IN THE
MEAN TIME...THE FA WILL MAINLY BE UNDER A SFC PRESSURE PATTERN AND
GRADIENT THAT SUPPORTS SW-WSW WINDS AT 10-15 KT WITH GUSTS UP TO
20 KT FOR THE REMAINDER OF THIS EVENING INTO THE PRE-DAWN TUE HRS.
WINDS WILL VEER TO THE NW-N BY DAYBREAK TUE AS THE SFC LOW
TRAVERSES THE LOCAL WATERS TO JUST OFFSHORE FROM CAPE FEAR. THE
LOW WILL FURTHER INTENSIFY DURING TUE...RESULTING IN GALE FORCE
WINDS OCCURRING DURING THE SHORT TERM PERIOD. SIGNIFICANT SEAS
WILL RANGE BETWEEN 2 AND 4 FT THE REMAINDER OF TONIGHT VIA LATEST
BUOY READINGS ACROSS AND NEARBY THE ILM WATERS. NO SIGNIFICANT
GROUND SWELL ILLUSTRATED BY LOCAL BUOYS AND WAVEWATCH3.
THERE4...LOCALLY PRODUCED WIND DRIVEN WAVES AT 5 TO 6 SECOND
DOMINATE PERIODS TO RULE THE SIGNIFICANT SEAS.
PREVIOUS DISCUSSION............................................
AS OF 3 PM MONDAY...NO SMALL CRAFT ADVISORY EXPECTED TONIGHT BUT
MARINE CONDITIONS WILL DETERIORATE SHORTLY AFTER DAYBREAK TUE. SW
WINDS PRECEDING AN APPROACHING COLD FRONT TONIGHT WILL REMAIN 15
KT OR LESS AS A SURFACE LOW LOOSENS THE LOCAL PRESSURE GRADIENT
AND PASSES OVERHEAD OF THE WATERS AROUND MIDNIGHT AND THEREAFTER.
ISOLATED TSTMS ARE POSSIBLE TONIGHT AND GUSTS TO 30-35 KT CANNOT
BE RULED. SEAS MAINLY AROUND 3 FEET IN THE WATERS WITH DOMINANT
PERIODS AROUND 6 SECONDS. WIND TO REMAIN SW THE MAJORITY OF THE
NIGHT...SHIFTING TO NNW-N INTO FIRST LIGHT TUESDAY.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY...GRADIENT WILL BE IN THE PROCESS OF TIGHTENING UP
TUE AM IN RESPONSE TO SURFACE LOW DEEPENING JUST EAST OF THE WATERS.
BASED ON LATEST FORECAST SOUNDINGS...NUMERICAL DATA AND COORDINATION
WITH SURROUNDING OFFICES HAVE DECIDED TO UPGRADE GALE WATCH TO A
WARNING WITH THE AFTERNOON PACKAGE. FORECAST SOUNDINGS ARE SHOWING
AROUND 40 KT NEAR THE TOP OF THE MIXED LAYER LATER TUE AND TUE
NIGHT. DESPITE STRONG WINDS LIMITED FETCH WILL KEEP SEAS UNDER 10 FT
ALTHOUGH WATERS OPEN TO EXTENDED NORTHERLY FETCH WILL APPROACH
DOUBLE DIGITS.
GRADIENT SLOWLY RELAXES ON WED AS THE LOW EXITS BUT NORTH TO
NORTHWEST FLOW WILL REMAIN CLOSE TO 20 KT FOR AT LEAST THE FIRST
HALF OF WED. WINDS DROP BELOW 15 KT LATER WED AND UNDER 10 KT WED
NIGHT AS WINDS BACK TO WEST AND THEN SOUTHWEST. SEAS WILL FALL BY 3
TO 4 FT FROM WED MORNING TO WED EVENING DUE TO WIND SHIFT AND
REDUCTION IN SPEED.
LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 3 PM MONDAY...A SMALL CRAFT ADVISORY WILL BE NEEDED ON
THURSDAY AS AN ARCTIC COLD FRONT BEARS DOWN ON THE REGION.
SOUTHWESTERLY FLOW WILL VEER SHARPLY LATE AFTERNOON WITH THIS
BOUNDARY`S PASSAGE. THE CHILLY AIR ASSOCIATED WITH THIS FRONT WILL
ENCOURAGE VERTICAL MIXING AND SOME GALE FORCE GUSTS APPEAR POSSIBLE.
CONDITIONS WILL BE SLOW TO ABATE AND THE ADVISORY SHOULD LAST MOST
IF NOT ALL OF THURSDAY NIGHT AND PERHAPS INTO EARLY FRIDAY. CENTER
OF HIGH PRESSURE OVER THE GULF COAST LATER FRIDAY KEEPING SLOW OUT
OF THE EARLY WITH A BACKING TOWARDS WEST POSSIBLE LATER IN THE DAY.
WEST TO SOUTHWESTERLY FLOW ON SATURDAY WILL INCREASE AHEAD OF THE
NEXT EVEN STRONG ARCTIC FRONT. WOULD NOT BE SURPRISED TO SEE GALE
WATCHES BY SATURDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...GALE WARNING FROM 9 AM TUESDAY TO 5 AM EST WEDNESDAY FOR
AMZ250-252-254-256.
&&
$$
SYNOPSIS...III
NEAR TERM...DCH/MJC
SHORT TERM...III
LONG TERM...MBB
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
836 PM EST MON FEB 9 2015
.SYNOPSIS...
SHOWERS DEVELOPING INLAND THIS AFTERNOON WILL SPREAD TO THE COAST
TONIGHT. A COLD FRONT WILL MOVE OFFSHORE EARLY TUESDAY MORNING
WITH MUCH COLDER TEMPERATURES TUESDAY AND WEDNESDAY. SEASONABLE
WEATHER WILL RETURN THURSDAY...BEFORE AN ARCTIC COLD FRONT CROSSES
THE AREA THURSDAY NIGHT. DRY BUT VERY COLD WEATHER WILL BECOME
ENTRENCHED FRIDAY THROUGH THE UPCOMING WEEKEND AND START OF NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 745 PM MONDAY...POPS ACROSS THE FA WERE RE-ARRANGED TO
ACCOUNT FOR THE SLOW EASTWARD PROGRESSION OF THE MAIN PCPN
SHIELD. HAVE INCLUDED ISOLATED THUNDER TIL MIDNIGHT...ASSOCIATED
WITH THE LEADING EDGE OF THE PCPN AS IT TRACKS EASTWARD DUE TO
WEAK LOW LEVEL CAPE VIA LATEST HRRR MODEL RUNS. THE CENTER OF THE
SFC LOW VIA RADAR LOOPS...IS CURRENTLY OVER DARLINGTON AND
FLORENCE COUNTIES OF SC. LOOK FOR ITS EASTWARD PROGRESSION TO
CONTINUE THIS EVENING...TO JUST OFF THE CAPE FEAR COAST LATE IN
THE PRE-DAWN TUE HOURS. BY DAYBREAK TUE...MODELS INDICATE THE LOW
WILL BE INTENSIFYING AT A DECENT CLIP AS IT CONTINUES TO PUSH
SLOWLY EASTWARD...TO THE OFFSHORE WATERS EAST OF CAPE FEAR.
BEHIND THE LOW...INCREASING SFC NW-N CAA WINDS WILL OVERSPREAD THE
FA MAINLY DURING THE MID TO LATE PRE-DAWN TUE HOURS. TONIGHTS
LOWS MAY ACTUALLY OCCUR DURING DAYLIGHT TUE MORNING...DEPENDING
HOW MUCH COLD AIR INFILTRATES THE FA.
PREVIOUS DISCUSSION..............................................
AS OF 3 PM MONDAY...MEASURABLE RAINFALL COVERED THE WESTERN
CAROLINAS THIS AFTERNOON AND WAS DRAWING CLOSER TO THE CENTRAL
PORTIONS OF THE STATES...ASSOCIATED WITH AN ENERGETIC SHORTWAVE
PLUGGING THROUGH GEORGIA PRESENTLY. CONVECTIVE ELEMENTS EMBEDDED
WITHIN THE RAIN AREA WERE TAKING SHAPE ACROSS CENTRAL SC AND MAY
BECOME PLAYERS ALONG AND WEST OF THE I-95 CORRIDOR INTO THE LATE
AFTERNOON. ISOLATED THUNDERSTORMS WILL BE RETAINED FOR THE NEAR
TERM FORECAST WITH A CATEGORICAL TO HIGHLY LIKELY OVERALL POP
DISTRIBUTION. SEVERE THREAT REMAINS LOW WITH GENERALLY ANEMIC WIND
SPEEDS IN THE LOW AND MID-LEVEL TROPOSPHERE PRECEDING THE FRONT.
GUSTS TO 40 KT HOWEVER CANNOT BE RULED OUT IN THE STRONGER CELLS.
LATEST SATELLITE DERIVED TOTAL PRECIPITABLE WATERS ANIMATIONS
SHOW 1 INCH WELLING NORTH-NORTHEAST INTO SC...AND LATEST WPC QPF
DEPICTIONS POINT TO 0.25-.075 INCH AVERAGES ACROSS NE SC AND SE
NC THROUGH 12Z TUESDAY. WITH CONVECTIVE INFLUENCES VARIATIONS TO
THESE BASIN AVERAGES CAN BE EXPECTED.
COLD AIR ADVECTION WILL ARRIVE LATE IN THE NEAR TERM PERIOD SO
MINIMUMS WITH CLOUD COVER AND WIND ARE APT TO DIP ONLY INTO THE
LOW 40S ACROSS INTERIOR SE NC AND MIDDLE AND UPPER 40S ELSEWHERE.
LOWS AROUND 50 ALONG AREA BEACHES BY FIRST LIGHT TUESDAY EXPECTED.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY...IMPRESSIVE SHORTWAVE OVERHEAD TUE MORNING
WILL MOVE OFF THE COAST DURING THE DAY...BECOMING NEARLY CUTOFF AT
5H AS IT DOES. MID LEVEL AMPLIFICATION SLOWS THE SYSTEM
DOWN...WITH CLOUD COVER AND PRECIP NOW LINGERING OVER THE REGION
INTO TUE AFTERNOON...ESPECIALLY ALONG THE COAST. UNDERNEATH THE 5H
TROUGH THE SURFACE LOW WILL STRENGTHEN...ENHANCING LOW LEVEL WIND
FIELD AND COLD ADVECTION. IMPRESSIVE 110KT+ 300 MB JET PASSING
SOUTH OF THE AREA TUE COMBINED WITH DEEPER WRAP AROUND MOISTURE
AND STEEP MID LEVEL LAPSE RATES MAY CONTRIBUTE TO SHOWERS DURING
THE FIRST HALF OF TUE. WILL BUMP UP INHERITED POP TO HIGH CHC
ALONG THE NC COAST TAPERING TO SLIGHT CHC FOR FAR SOUTHWESTERN
AREAS THROUGH MIDDAY. BOTH MOISTURE AND MID LEVEL INSTABILITY
DECREASE TUE AFTERNOON BUT WILL HOLD ONTO SLIGHT CHC POP ALONG THE
NC COAST INTO TUE EVENING GIVEN THE PROXIMITY TO THE STACKED LOW
JUST OFF THE COAST. INCOMING AIR MASS IS NOT PARTICULARLY COLD BUT
THE STRENGTH OF THE NORTHERLY FLOW AND CLOUD COVER WILL MAXIMIZE
THE COLD AIR AND KEEP TEMPS BELOW CLIMO. NORTHERLY FLOW CONTINUES
TUE NIGHT KEEPING LOWS NEAR TO BELOW CLIMO.
NORTHERLY FLOW WED MORNING BACKS TO WEST-NORTHWEST AS THE LOW OFF
THE COAST MOVES AWAY FROM THE AREA. WESTERLY FLOW ALOFT AND LOW
LEVEL NORTHWEST FLOW WILL RESULT IN SOME DOWNSLOPE COMPONENT BUT
LIMITED WARMING WED WILL BE MORE DUE TO AIR MASS MODIFICATION UNDER
SUNNY SKIES. SOUTHERN EXTENT OF THE SURFACE HIGH MOVES EAST OF THE
AREA LATER WED INTO WED NIGHT WITH LIGHT RETURN FLOW DEVELOPING.
TEMPERATURES WILL REMAIN BELOW CLIMO WED AND WED NIGHT.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 3 PM MONDAY...
EXTREME COLD ON THE WAY LATE IN THE PERIOD...
THURSDAY WILL BE ONE LAST MILD DAY THANKS TO SOUTHWESTERLY FLOW
AHEAD OF AN ARCTIC COLD FRONT THAT ARRIVES LATE IN THE DAY. ITS
PASSAGE WILL BE MOISTURE-STARVED IN THE LOW LEVELS. THE GFS HAS A
RELATIVELY NEW IDEA IN THAT THE MID LEVEL VORT IS STRONG ENOUGH
(36S-1) THAT A LITTLE QPF IS WRUNG OUT OVER NC ZONES POSSIBLY AFTER
TEMPS GET BELOW PTYPE THRESHOLDS. THE EURO IS NOT AS STRONG OR FAR
SOUTH WITH THE VORT CENTER AND SHOWS A MORE BELIEVABLE
NON-MEASURABLE QPF FORECAST JUST GLANCING CAPE FEAR REGION. WILL
LEAVE FORECAST DRY. THE COLD THAT FOLLOWS WILL BE THE REAL NEWS
ANYWAY. TEMPS DROP INTO THE 20S THURSDAY NIGHT AND WILL BE HARD
PRESSED TO TOP 40 ON FRIDAY. THERE WILL BE SOME SMALL RECOVERY ON
SATURDAY SINCE THE LOW LEVEL WINDS WILL BACK AHEAD OF THE NEXT
APPROACHING VORT CENTER. THIS WILL BE SHORT LIVED HOWEVER AS BY
SATURDAY AFTERNOON AN ARCTIC DISCHARGE INTO THE CAROLINAS GETS
UNDERWAY...THE LIKES OF WHICH IM NOT SURE IVE EVER SEEN. THE GFS
AND ECMWF HAVE BEEN WAFFLING ON THE MAGNITUDE OF THE COLD BUT THEY
ARE COMING INTO BETTER AGREEMENT TODAY THAT 850MB TEMPS BOTTOM OUT
ON SUNDAY ANYWHERE FROM ABOUT -18C (EC) TO -21C (GFS). THIS
AIRMASS WILL BE TRAVELING OVER AMPLE SNOW COVER TO RETAIN IT PUNCH
THIS FAR SOUTH AND SUNDAY HIGHS WILL REMAIN BELOW FREEZING AND
TEENS APPEAR LIKELY SUNDAY NIGHT. MEX MOS FOR ILM SHOWS A HIGH OF
35 BUT ITS INCREASED WEIGHT TOWARDS CLIMO IS TO BLAME.
INTERESTINGLY THE 06Z MOS HAD AN INCREDIBLE 24...FOR A HIGH. THAT
COULD BE MUCH CLOSER TO REALITY. GIVEN THAT THIS AIRMASS TRAVELS
ACROSS SNOW AND MAY BE DRIVEN DOWN THE EAST OF THE MOUNTAINS THERE
MAY BE A TONGUE OF EVEN COLD AIR LIKE WHAT THE GFS SHOWED A FEW
DAYS AGO (850MB TEMPS CLOSER TO -26C). 850MB TEMPS MAY `WARM` BACK
TO 0C BEFORE MONDAY IS THROUGH.
&&
.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
AS OF 00Z...AT KFLO/KLBT AN AREA OF LIGHT TO MODERATE RAIN WITH
EMBEDDED HEAVIER SHOWERS WILL AFFECT THE TERMINALS THIS EVENING.
PREDOMINATE MVFR VSBYS LIKELY WITH TEMPO IFR VSBYS IN THE HEAVIER
SHOWERS. TOWARDS MIDNIGHT Z RAIN DECREASES BUT PREDOMINATE MVFR CIGS
WILL DEVELOP AND PERSIST THROUGH THE TAF VALID PERIOD. THERE IS
MODERATE CONFIDENCE FROM 06-14Z IFR CIGS WILL OCCUR. A SECONDARY
SURGE OF COLD AIR SHOULD MOVE THROUGH BEFORE SUNRISE. THIS SHOULD
RESULT IN STRONG AND GUSTY NORTH WINDS TO DEVELOP AND COULD CAUSE
IFR CIGS TO IMPROVE TO MVFR QUICKER THAN INDICATED IN TAFS.
AT THE COASTAL TERMINALS VFR EXPECTED THROUGH EARLY THIS EVENING. AS
WINDS DECREASE BR WILL BECOME AN ISSUE LATE THIS EVENING. HAVE
INDICATE TEMPO MVFR VSBYS...ALTHOUGH IFR VSBYS COULD OCCUR AFTER 04Z
PER NAM BUFFER SOUNDINGS. IFR/LIFR CIG/VSBYS SEEM LIKELY OVERNIGHT WITH
PERIODS OF LIGHT RAIN. A SECONDARY SURGE OF COLD AIR SHOULD MOVE
THROUGH BEFORE SUNRISE. THIS SHOULD RESULT IN STRONG AND GUSTY NORTH
WINDS TO DEVELOP AND SHOULD CAUSE VSBYS TO IMPROVE TO VFR. BUT LIFR
CIGS COULD PERSIST THROUGH SUNRISE...AFTER WHICH MVFR CIGS
EXPECTED. IFR CIGS ARE INDICATED BY GFS MOS GUIDANCE THROUGH THE DAY
AT ALL COASTAL TERMINALS...BUT HAVE SIDED WITH MET GUIDANCE AS IT
AGREES WITH GFS TIME HEIGHT ANALYSIS WHICH SUGGEST THE HIGHER CIGS.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM MONDAY...NO SMALL CRAFT ADVISORY EXPECTED TONIGHT BUT
MARINE CONDITIONS WILL DETERIORATE SHORTLY AFTER DAYBREAK TUE. SW
WINDS PRECEDING AN APPROACHING COLD FRONT TONIGHT WILL REMAIN 15
KT OR LESS AS A SURFACE LOW LOOSENS THE LOCAL PRESSURE GRADIENT
AND PASSES OVERHEAD OF THE WATERS AROUND MIDNIGHT AND THEREAFTER.
ISOLATED TSTMS ARE POSSIBLE TONIGHT AND GUSTS TO 30-35 KT CANNOT
BE RULED. SEAS MAINLY AROUND 3 FEET IN THE WATERS WITH DOMINANT
PERIODS AROUND 6 SECONDS. WIND TO REMAIN SW THE MAJORITY OF THE
NIGHT...SHIFTING TO NNW-N INTO FIRST LIGHT TUESDAY.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY...GRADIENT WILL BE IN THE PROCESS OF TIGHTENING UP
TUE AM IN RESPONSE TO SURFACE LOW DEEPENING JUST EAST OF THE WATERS.
BASED ON LATEST FORECAST SOUNDINGS...NUMERICAL DATA AND COORDINATION
WITH SURROUNDING OFFICES HAVE DECIDED TO UPGRADE GALE WATCH TO A
WARNING WITH THE AFTERNOON PACKAGE. FORECAST SOUNDINGS ARE SHOWING
AROUND 40 KT NEAR THE TOP OF THE MIXED LAYER LATER TUE AND TUE
NIGHT. DESPITE STRONG WINDS LIMITED FETCH WILL KEEP SEAS UNDER 10 FT
ALTHOUGH WATERS OPEN TO EXTENDED NORTHERLY FETCH WILL APPROACH
DOUBLE DIGITS.
GRADIENT SLOWLY RELAXES ON WED AS THE LOW EXITS BUT NORTH TO
NORTHWEST FLOW WILL REMAIN CLOSE TO 20 KT FOR AT LEAST THE FIRST
HALF OF WED. WINDS DROP BELOW 15 KT LATER WED AND UNDER 10 KT WED
NIGHT AS WINDS BACK TO WEST AND THEN SOUTHWEST. SEAS WILL FALL BY 3
TO 4 FT FROM WED MORNING TO WED EVENING DUE TO WIND SHIFT AND
REDUCTION IN SPEED.
LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 3 PM MONDAY...A SMALL CRAFT ADVISORY WILL BE NEEDED ON
THURSDAY AS AN ARCTIC COLD FRONT BEARS DOWN ON THE REGION.
SOUTHWESTERLY FLOW WILL VEER SHARPLY LATE AFTERNOON WITH THIS
BOUNDARY`S PASSAGE. THE CHILLY AIR ASSOCIATED WITH THIS FRONT WILL
ENCOURAGE VERTICAL MIXING AND SOME GALE FORCE GUSTS APPEAR POSSIBLE.
CONDITIONS WILL BE SLOW TO ABATE AND THE ADVISORY SHOULD LAST MOST
IF NOT ALL OF THURSDAY NIGHT AND PERHAPS INTO EARLY FRIDAY. CENTER
OF HIGH PRESSURE OVER THE GULF COAST LATER FRIDAY KEEPING SLOW OUT
OF THE EARLY WITH A BACKING TOWARDS WEST POSSIBLE LATER IN THE DAY.
WEST TO SOUTHWESTERLY FLOW ON SATURDAY WILL INCREASE AHEAD OF THE
NEXT EVEN STRONG ARCTIC FRONT. WOULD NOT BE SURPRISED TO SEE GALE
WATCHES BY SATURDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...GALE WARNING FROM 9 AM TUESDAY TO 5 AM EST WEDNESDAY FOR
AMZ250-252-254-256.
&&
$$
SYNOPSIS...III
NEAR TERM...DCH/MJC
SHORT TERM...III
LONG TERM...MBB
AVIATION...MRR
MARINE...
AREA FORECAST DISCUSSION
NWS BISMARCK ND
952 PM CST MON FEB 9 2015
.UPDATE...
ISSUED AT 952 PM CST MON FEB 9 2015
NO SIGNIFICANT CHANGES FOR THE LATE EVENING UPDATE. REFLECTIVITIES
CONTINUE TO INCREASE ACROSS WESTERN AND INTO CENTRAL NORTH DAKOTA.
REPORTS OF FREEZING RAIN IN WESTERN NORTH DAKOTA. ALSO NOTICED
SOME VERY LIGHT FREEZING RAIN AND ICE PELLETS AT WFO BISMARCK THIS
PAST HOUR. DID CANCEL THE DENSE FOG ADVISORY AS EXCEPT FOR
HETTINGER...VISIBILITIES HAVE IMPROVED TO AROUND A MILE OR GREATER
IN MOST AREAS IN THE ADVISORY. NO CHANGES TO CURRENT WINTER
WEATHER HEADLINES. WILL FRESHEN UP TEXT PRODUCTS SHORTLY.
UPDATE ISSUED AT 600 PM CST MON FEB 9 2015
NO CHANGES TO CURRENT WINTER WEATHER OR FREEZING RAIN ADVISORIES.
DID EXTEND THE DENSE FOG ADVISORY THROUGH 10 PM THIS EVENING.
STILL SURFACE REPORTS AND WEATHER CAMERAS SHOWING DENSE FOG. THINK
WITH THE SYSTEM MOVING IN THROUGH THE EVENING VISIBILITIES WILL
BEGIN TO IMPROVE. NO ADDITIONAL CHANGES AT THIS TIME. WILL TAKE A
CLOSER LOOK AT TEMPERATURES AND PRECIPITATION WITH NEXT UPDATE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 400 PM CST MON FEB 9 2015
THE UPCOMING MIXED PRECIPITATION EVENT HIGHLIGHTS THE SHORT TERM
FORECAST.
IN REGARDS TO HEADLINES...WILL LET THE DENSE FOG ADVISORY ACROSS
MUCH OF THE WEST AND CENTRAL CONTINUE THROUGH 00 UTC WITH
CONTINUED UPSLOPE SOUTHEASTERLY FLOW. OTHER THAN ADDING
SIOUX...GRANT...STARK AND HETTINGER COUNTIES TO THE FREEZING RAIN
ADVISORY...ALL OTHER WINTER HEADLINES REMAIN UNCHANGED.
IN GENERAL...OVERALL EXPECTATIONS FOR THE EVENT VARY LITTLE WITH
THIS FORECAST PACKAGE THAT UTILIZED THE 12 AND INCOMING 18 UTC
DETERMINISTIC AND ENSEMBLE SUITES COMPARED TO THE 06 AND 00 UTC
GUIDANCE. THE 18 THROUGH 20 UTC HRRR ITERATIONS LINE UP WELL WITH
RADAR ACROSS EASTERN MONTANA AND WILL WEIGH HEAVILY ON THESE
SOLUTIONS IN THE NEAR TERM...BLENDED TO THE GLOBAL 12 AND 18 UTC
SUITES THROUGH THE NIGHT. THIS SUPPORTS AN EXPANDED THREAT FOR
FREEZING RAIN INTO SOUTHWEST NORTH DAKOTA GIVEN SURFACE
TEMPERATURES THAT HAVE REMAINED BELOW FREEZING UNDER THE STRATUS.
FOLLOWED CLOSELY TO THE 19-20 UTC RAP AND 18 UTC NAM BUFR
SOUNDINGS FOR THE STRENGTH OF THE WARM LAYER ALOFT. AS ALWAYS IN
MIXED PRECIPITATION TYPES EVENTS...THIS VARIABLE IS THE MOST
UNCERTAIN. EXPECT THE WARM LAYER ALOFT TO SUPPORT LIQUID TO THE
SURFACE FROM NORTHWEST THROUGH SOUTH CENTRAL NORTH DAKOTA THROUGH
10-12 UTC...BEFORE A TRANSITION TO A SLEET AND SNOW MIX AND AN
EVENTUAL END TO PRECIPITATION WITH A DRY SLOT OVERTAKING THE AREA.
FOR LOCATIONS ALONG AND NORTH OF HIGHWAYS 2 AND
52....PRECIPITATION IS EXPECTED TO BE ALL SNOW...WITH A SLIGHT
CHANCE FOR FREEZING DRIZZLE GIVEN LOW LEVEL SATURATION WARMER
THAN -10 C UNTIL THE FULL COLUMN CAN SATURATE AND SUPPORT ICE
CRYSTALS TO THE GROUND. THE 18 UTC GFS/NAM HAVE BOTH COME IN WITH
HIGHER QPF...ESPECIALLY ACROSS THE JAMES RIVER VALLEY INTO THE
TURTLE MOUNTAINS IN THE 06-12 UTC TIME FRAME. THIS TREND WILL HAVE
TO BE MONITORED IN THE 00 UTC RUNS...AS THIS WOULD LEAD TO HIGHER
SNOWFALL...AND POSSIBLE GREATER ICE ACCUMULATIONS IN THE SOUTHERN
JAMES RIVER VALLEY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 410 PM CST MON FEB 9 2015
...THE MAIN IMPACT IN THE LONG TERM IS COLD...
TUESDAY`S SYSTEM WILL DEPART THE REGION BY LATE TUESDAY NIGHT.
SCATTERED LIGHT SNOW WILL DIMINISH THROUGH THE EVENING HOURS WITH
LITTLE TO NO ADDITIONAL ACCUMULATION EXPECTED.
THE REST OF THE LONG TERM FORECAST LOOKS RATHER COLD ACROSS THE
EAST AND MILD ACROSS THE SOUTHWEST. A COLD AND DRY ARCTIC AIRMASS
WILL ENTER WEDNESDAY INTO THURSDAY. A STRONG SURFACE HIGH WILL
SETTLE ACROSS THE AREA THURSDAY MORNING...WHICH COULD LEAD TO VERY
COLD TEMPERATURES...AROUND 20 BELOW...ACROSS NORTH CENTRAL NORTH
DAKOTA.
A WARM FRONT IS THEN EXPECTED TO ENTER WESTERN NORTH DAKOTA
THURSDAY AFTERNOON AND EVENING WHICH SHOULD BRING MUCH WARMER
TEMPERATURES WESTERN NORTH DAKOTA. OVERALL THE LONG TERM LOOKS
RATHER DRY...WITH A FEW FLURRIES POSSIBLE THURSDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 952 PM CST MON FEB 9 2015
WIDESPREAD IFR TO LIFR CONDITIONS IN FOG AND STRATUS WILL CONTINUE
THIS AFTERNOON AND INTO THE EVENING ACROSS WESTERN AND CENTRAL
NORTH DAKOTA. ANOTHER ROUND OF LIGHT FREEZING RAIN WILL
OVERSPREAD KISN/KDIK/KBIS BETWEEN 00Z AND 06Z TUESDAY...WITH LIGHT
SNOW DEVELOPING OVER KMOT AND LIGHT SNOW AND SLEET AT KJMS MONDAY
NIGHT. CONTINUED IFR CONDITIONS EXPECTED.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY UNTIL NOON CST /11 AM MST/ TUESDAY FOR
NDZ019>022-034>036-042-045>047-050.
FREEZING RAIN ADVISORY UNTIL 6 AM CST /5 AM MST/ TUESDAY FOR
NDZ001-009-010-017-018-033-041.
WINTER WEATHER ADVISORY UNTIL NOON CST TUESDAY FOR NDZ002-003-
011.
WINTER WEATHER ADVISORY UNTIL 6 PM CST TUESDAY FOR NDZ004-005-
012-013-023-025-037-048-051.
&&
$$
UPDATE...TWH
SHORT TERM...AJ
LONG TERM...AYD
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
600 PM CST MON FEB 9 2015
.UPDATE...
ISSUED AT 600 PM CST MON FEB 9 2015
NO CHANGES TO CURRENT WINTER WEATHER OR FREEZING RAIN ADVISORIES.
DID EXTEND THE DENSE FOG ADVISORY THROUGH 10 PM THIS EVENING.
STILL SURFACE REPORTS AND WEATHER CAMERAS SHOWING DENSE FOG. THINK
WITH THE SYSTEM MOVING IN THROUGH THE EVENING VISIBILITIES WILL
BEGIN TO IMPROVE. NO ADDITIONAL CHANGES AT THIS TIME. WILL TAKE A
CLOSER LOOK AT TEMPERATURES AND PRECIPITATION WITH NEXT UPDATE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 400 PM CST MON FEB 9 2015
THE UPCOMING MIXED PRECIPITATION EVENT HIGHLIGHTS THE SHORT TERM
FORECAST.
IN REGARDS TO HEADLINES...WILL LET THE DENSE FOG ADVISORY ACROSS
MUCH OF THE WEST AND CENTRAL CONTINUE THROUGH 00 UTC WITH
CONTINUED UPSLOPE SOUTHEASTERLY FLOW. OTHER THAN ADDING
SIOUX...GRANT...STARK AND HETTINGER COUNTIES TO THE FREEZING RAIN
ADVISORY...ALL OTHER WINTER HEADLINES REMAIN UNCHANGED.
IN GENERAL...OVERALL EXPECTATIONS FOR THE EVENT VARY LITTLE WITH
THIS FORECAST PACKAGE THAT UTILIZED THE 12 AND INCOMING 18 UTC
DETERMINISTIC AND ENSEMBLE SUITES COMPARED TO THE 06 AND 00 UTC
GUIDANCE. THE 18 THROUGH 20 UTC HRRR ITERATIONS LINE UP WELL WITH
RADAR ACROSS EASTERN MONTANA AND WILL WEIGH HEAVILY ON THESE
SOLUTIONS IN THE NEAR TERM...BLENDED TO THE GLOBAL 12 AND 18 UTC
SUITES THROUGH THE NIGHT. THIS SUPPORTS AN EXPANDED THREAT FOR
FREEZING RAIN INTO SOUTHWEST NORTH DAKOTA GIVEN SURFACE
TEMPERATURES THAT HAVE REMAINED BELOW FREEZING UNDER THE STRATUS.
FOLLOWED CLOSELY TO THE 19-20 UTC RAP AND 18 UTC NAM BUFR
SOUNDINGS FOR THE STRENGTH OF THE WARM LAYER ALOFT. AS ALWAYS IN
MIXED PRECIPITATION TYPES EVENTS...THIS VARIABLE IS THE MOST
UNCERTAIN. EXPECT THE WARM LAYER ALOFT TO SUPPORT LIQUID TO THE
SURFACE FROM NORTHWEST THROUGH SOUTH CENTRAL NORTH DAKOTA THROUGH
10-12 UTC...BEFORE A TRANSITION TO A SLEET AND SNOW MIX AND AN
EVENTUAL END TO PRECIPITATION WITH A DRY SLOT OVERTAKING THE AREA.
FOR LOCATIONS ALONG AND NORTH OF HIGHWAYS 2 AND
52....PRECIPITATION IS EXPECTED TO BE ALL SNOW...WITH A SLIGHT
CHANCE FOR FREEZING DRIZZLE GIVEN LOW LEVEL SATURATION WARMER
THAN -10 C UNTIL THE FULL COLUMN CAN SATURATE AND SUPPORT ICE
CRYSTALS TO THE GROUND. THE 18 UTC GFS/NAM HAVE BOTH COME IN WITH
HIGHER QPF...ESPECIALLY ACROSS THE JAMES RIVER VALLEY INTO THE
TURTLE MOUNTAINS IN THE 06-12 UTC TIME FRAME. THIS TREND WILL HAVE
TO BE MONITORED IN THE 00 UTC RUNS...AS THIS WOULD LEAD TO HIGHER
SNOWFALL...AND POSSIBLE GREATER ICE ACCUMULATIONS IN THE SOUTHERN
JAMES RIVER VALLEY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 410 PM CST MON FEB 9 2015
...THE MAIN IMPACT IN THE LONG TERM IS COLD...
TUESDAY`S SYSTEM WILL DEPART THE REGION BY LATE TUESDAY NIGHT.
SCATTERED LIGHT SNOW WILL DIMINISH THROUGH THE EVENING HOURS WITH
LITTLE TO NO ADDITIONAL ACCUMULATION EXPECTED.
THE REST OF THE LONG TERM FORECAST LOOKS RATHER COLD ACROSS THE
EAST AND MILD ACROSS THE SOUTHWEST. A COLD AND DRY ARCTIC AIRMASS
WILL ENTER WEDNESDAY INTO THURSDAY. A STRONG SURFACE HIGH WILL
SETTLE ACROSS THE AREA THURSDAY MORNING...WHICH COULD LEAD TO VERY
COLD TEMPERATURES...AROUND 20 BELOW...ACROSS NORTH CENTRAL NORTH
DAKOTA.
A WARM FRONT IS THEN EXPECTED TO ENTER WESTERN NORTH DAKOTA
THURSDAY AFTERNOON AND EVENING WHICH SHOULD BRING MUCH WARMER
TEMPERATURES WESTERN NORTH DAKOTA. OVERALL THE LONG TERM LOOKS
RATHER DRY...WITH A FEW FLURRIES POSSIBLE THURSDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 600 PM CST MON FEB 9 2015
WIDESPREAD IFR TO LIFR CONDITIONS IN FOG AND STRATUS WILL CONTINUE
THIS AFTERNOON AND INTO THE EVENING ACROSS WESTERN AND CENTRAL
NORTH DAKOTA. ANOTHER ROUND OF LIGHT FREEZING RAIN WILL
OVERSPREAD KISN/KDIK/KBIS BETWEEN 00Z AND 06Z TUESDAY...WITH LIGHT
SNOW DEVELOPING OVER KMOT AND LIGHT SNOW AND SLEET AT KJMS MONDAY
NIGHT. CONTINUED IFR CONDITIONS EXPECTED.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 PM CST /9 PM MST/ THIS EVENING FOR
NDZ009-010-017>020-031>034-040>045.
FREEZING RAIN ADVISORY FROM 9 PM CST /8 PM MST/ THIS EVENING TO
NOON CST /11 AM MST/ TUESDAY FOR NDZ019>022-034>036-042-045>047-
050.
FREEZING RAIN ADVISORY UNTIL 6 AM CST /5 AM MST/ TUESDAY FOR
NDZ001-009-010-017-018-033-041.
WINTER WEATHER ADVISORY UNTIL NOON CST TUESDAY FOR NDZ002-003-
011.
WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO 6 PM CST
TUESDAY FOR NDZ004-005-012-013-023-025-037-048-051.
&&
$$
UPDATE...TWH
SHORT TERM...AJ
LONG TERM...AYD
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1155 PM CST SAT FEB 7 2015
.UPDATE...
ISSUED AT 1155 PM CST SAT FEB 7 2015
MAIN UPDATE WAS TO ADD COUNTIES INTO THE FREEZING RAIN ADVISORY
WHICH WILL FILL THE GAP OVER SOUTH CENTRAL NORTH DAKOTA THROUGH
SUNDAY MORNING. THE LATEST LOCAL/REGIONAL RADAR SHOWS AN AREA OF
LIGHT PRECIPITATION OVER NORTHEAST MONTANA...STREAMING SOUTHEAST TO
WILLISTON...DICKINSON AND ACROSS FAR SOUTH CENTRAL NORTH DAKOTA.
NORTHEAST WINDS CONTINUE TO PUSH THE BAROCLINIC ZONE FARTHER INTO
THE SOUTHWEST. TEMPERATURES AT KBIS ARE NOW AT FREEZING. LATEST
WATER VAPOR SHOWS A SHORTWAVE TROUGH OVER EASTERN MONTANA WHICH IS
FORECAST TO SLIDE EAST OVERNIGHT INTO SUNDAY MORNING...RIDING OVER
THE STALLED FRONT. HIGH RESOLUTION MODEL GUIDANCE ALONG WITH THE
OPERATIONAL NAM/GFS INDICATE POCKETS/AREAS OF PRECIPITATION ACROSS
SOUTH CENTRAL NORTH DAKOTA WHERE SURFACE TEMPERATURES WILL BE
BELOW FREEZING OVERNIGHT THROUGH SUNDAY MORNING. THUS HAVE
DECIDED TO FILL IN THE GAP OVER SOUTH CENTRAL NORTH DAKOTA WITH A
FREEZING RAIN ADVISORY THROUGH NOON CST SUNDAY. UPDATES TO THE
TEXT PRODUCTS FORTHCOMING.
UPDATE ISSUED AT 952 PM CST SAT FEB 7 2015
TWO MAIN FORECAST CONCERNS THIS EVENING...THE CURRENT FREEZING
RAIN ADVISORY...AND THE FAR SOUTHEAST CWA. NOT MUCH GOING ON IN
THE CURRENT ADVISORY...BUT AN AREA OF PRECIP OVER NORTHEAST
MONTANA IS FORECAST TO MOVE INTO THE ADVISORY AREA SHORTLY. COULD
STILL SEE SOME FREEZING RAIN LATER TONIGHT SO WILL CONTINUE THE
ADVISORY FOR NOW.
OVER SOUTHWEST AND SOUTH CENTRAL NORTH DAKOTA. WE HAVE BEEN
GETTING RAIN THIS EVENING. FORTUNATELY MOST AREAS WERE QUITE WARM
TODAY AND SURFACE TEMPERATURES ARE SLOW TO FALL. THINK PRECIP
SHOULD BE OUT OF MOST OF THE AREA BEFORE TEMPERATURES FALL TO
CRITICAL VALUES.
THE EXCEPTION IS IN OUR FAR SOUTHEAST CWA. PERSISTENT BAND OF
LIGHT RAIN NORTHWEST TO SOUTHEAST ACROSS DICKEY AND LAMOURE
COUNTIES. TEMPERATURES HERE WERE MUCH COOLER TODAY AND OAKES IS
CURRENTLY RECEIVING LIGHT RAIN WITH 32 DEGREES. WILL ADD THESE TWO
COUNTIES TO THE ADVISORY.
UPDATED TEXT PRODUCTS OUT SHORTLY.
UPDATE ISSUED AT 643 PM CST SAT FEB 7 2015
LATEST SATELLITE IMAGERY INDICATED SOME COOLING CLOUD TOPS ACROSS
NORTHWEST INTO SOUTH CENTRAL NORTH DAKOTA. THIS LINES UP WELL WITH
LATEST RADAR INDICATING AN ENHANCED AREA OF REFLECTIVITIES FROM
WILLISTON AND WATFORD CITY SOUTHEAST THROUGH BEULAH TO BISMARCK.
LATEST WEATHER CAMERAS AND REPORTS INDICATE PRECIPITATION UNDER
THE HIGHER REFLECTIVITIES IS REACHING THE GROUND. ONLY TRACE
AMOUNTS SO FAR IN THIS LEADING BAND AND TEMPERATURES MOST AREAS
ARE ABOVE FREEZING. DID EXPAND CHANCE POPS INTO SOUTH CENTRAL
NORTH DAKOTA FROM BISMARCK DOWN TOWARDS ASHLEY AND ELLENDALE EARLY
THIS EVENING. ONE POTENTIAL PROBLEM IS THE COLDER TEMPERATURES
OVER THE ELLENDALE AND ASHLEY AREA ON THE COLD SIDE OF THE
BAROCLINIC ZONE. IF THE EARLY EVENING PRECIPITATION REACHES THE
GROUND IN THESE AREAS WE COULD SEE SOME LIGHT MIXED PRECIPITATION
OR FREEZING RAIN. WILL CONTINUE TO MONITOR BUT AT THIS TIME WILL
NOT ISSUE ANYTHING AS AMOUNTS WOULD BE MAINLY TRACE THIS EVENING
AND THEN BY LATE EVENING THEY SHOULD BE COLD ENOUGH FOR SNOW BASED
ON UTILIZING THE WET BULB FOR MAX TEMPERATURE ALOFT. UPDATED
CURRENT TEMPERATURES AND UTILIZED THE SHORT TERM CONSENSUS
FORECAST FOR HOURLY TEMPERATURES TONIGHT...WHICH BETTER CAPTURED
THE QUICKER THAN EXPECTED COOLING ACROSS THE SOUTHWEST AND SOUTH
CENTRAL. UPDATED TEXT PRODUCTS WILL BE SENT SHORTLY.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 331 PM CST SAT FEB 7 2015
MIXED PRECIPITATION TYPES THIS EVENING AND TONIGHT HIGHLIGHT THE
SHORT TERM FORECAST.
ISSUED A FREEZING RAIN ADVISORY FOR NORTHWEST INTO PORTIONS OF
CENTRAL NORTH DAKOTA THROUGH LAKE SAKAKAWEA FROM 03 UTC THIS
EVENING THROUGH 12 UTC SUNDAY MORNING. THE 12 UTC WRF-ARW/NMM AND
ECMWF...18 UTC NAM AND 18-20 UTC HRRR ITERATIONS ARE IN AGREEMENT
ON THE BAND OF PRECIPITATION OBSERVED ACROSS EASTERN MONTANA AS OF
2120 UTC CONTINUING TO DEVELOP ACROSS WESTERN THROUGH SOUTHEAST
NORTH DAKOTA THIS EVENING AND THROUGH THE NIGHT. PRECIPITATION IS
EXPECTED TO START OUT AS RAIN BEFORE A TRANSITION THROUGH A MIX OF
FREEZING RAIN...SLEET AND SNOW THROUGH THE NIGHT. NORTHWEST NORTH
DAKOTA...SOUTHEAST THROUGH LAKE SAKAKAWEA IS WHERE CONFIDENCE OF
ICE ACCUMULATIONS OF UP TO ONE-TENTH IS GREATEST. THIS IS
SUPPORTED BY THE 18 UTC NAM BUFR AND 18-20 UTC RAP SOUNDINGS.
FURTHER SOUTHEAST INTO SOUTH CENTRAL NORTH DAKOTA...UNCERTAINTY
REMAINS AS TO HOW QUICKLY SURFACE TEMPERATURES WILL FALL BELOW
FREEZING WITH 21 UTC TEMPERATURES IN THE 40S AND 50S. GIVEN
INCREASING CLOUD COVER...TEMPERATURES MAY REMAIN ABOVE FREEZING
MUCH OF THE NIGHT SOUTH CENTRAL TO LIMIT THE FREEZING RAIN THREAT.
WILL ALLOW FURTHER SHIFTS TO EVALUATE AND A POSSIBLE EXPANSION OF
THE ADVISORY FOR TONIGHT INTO SUNDAY MORNING IS CERTAINLY NOT OUT
OF THE QUESTION.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 331 PM CST SAT FEB 7 2015
MAIN CONCERN IN THE LONG TERM INVOLVES PRECIPITATION TYPE AND
AMOUNTS BEGINNING MONDAY AFTERNOON AND CONTINUING THROUGH TUESDAY
NIGHT TIME FRAME.
SUNDAY NIGHT THE SYSTEM AFFECTING THE STATE SATURDAY NIGHT/SUNDAY
WILL BE EXITING TO THE EAST...WITH LINGERING CHANCES OF LIGHT SNOW
OVER PORTIONS OF CENTRAL NORTH DAKOTA SUNDAY EVENING.
A SHORTWAVE RIDGE MOVING INTO THE AREA MONDAY SHOULD KEEP LATE
SUNDAY NIGHT AND MONDAY MORNING QUIET.
MONDAY AFTERNOON THROUGH TUESDAY NIGHT:
THE LEADING EDGE OF UPPER LEVEL ENERGY FROM THE NEXT SYSTEM REACHES
WESTERN NORTH DAKOTA MONDAY AFTERNOON. A SHORTWAVE TROUGH MOVES OUT
OF THE ROCKIES AND ACROSS THE DAKOTAS MONDAY NIGHT THROUGH TUESDAY
NIGHT. THE ACCOMPANYING SURFACE LOW/BOUNDARY THAT SETS UP AND
EVOLVES THROUGHOUT THE EVENT WILL BRING WARM AIR FROM THE SOUTHWEST
AND COOL AIR FROM THE NORTHEAST. TEMPERATURE PROFILES DURING THIS
TIME SUGGEST MOSTLY RAIN OR FREEZING RAIN OVER THE SOUTHWEST PART OF
THE STATE...AND MAINLY SNOW OR SLEET OVER THE NORTH CENTRAL THROUGH
THE JAMES VALLEY. A WINTRY MIX OF RAIN...FREEZING RAIN...SLEET AND
SNOW IS POSSIBLE FROM NORTHWEST THROUGH SOUTH CENTRAL.
LOOKING AT A MIX OF PRECIPITATION NORTHWEST MONDAY AFTERNOON. MONDAY
NIGHT THROUGH TUESDAY IS WHEN THE SOUTHWEST SHOULD SEE RAIN OR
FREEZING RAIN...AND A MIX OF FREEZING RAIN AND SNOW NORTHWEST
THROUGH SOUTH CENTRAL...WITH MAINLY SNOW NORTH CENTRAL THROUGH THE
JAMES VALLEY.
SNOW ACCUMULATIONS NORTHWEST THROUGH THE JAMES VALLEY MAINLY LATE
MONDAY NIGHT THROUGH TUESDAY NIGHT. MAIN FREEZING RAIN THREAT SOUTH
AND WEST OF THE MISSOURI RIVER MONDAY NIGHT.
QUIET WEATHER START TO RETURN ON SUNDAY AS RIDGE OVER THE WESTERN
CONUS AMPLIFIES AND MAIN SHORT WAVE SLIDES OFF TO THE
EAST...THOUGH SOME LIGHT PRECIP MAY LINGER INTO THE MORNING HOURS
BEFORE EXITING. VERY WEAK SHORT WAVE SLIDES THROUGH AROUND MID-
DAY...BUT AT THIS POINT LOOKS AS THIS SHOULD ONLY KEEP SOME CLOUDS
AROUND.
DRY AND COOLER WEATHER EXPECTED FOR MID-WEEK BEHIND THE SHORTWAVE
TROUGH...WITH A WARMING TREND BY THE END OF THE WEEK AS RIDGE OVER
THE WESTERN CONUS SLOWLY AMPLIFIES AND SHIFTS SLIGHTLY EAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1155 PM CST SAT FEB 7 2015
LATEST HRRR/NUMERICAL GUIDANCE CONTINUE TO INDICATE IFR CEILINGS
DEVELOPING ACROSS CENTRAL NORTH DAKOTA ALONG A STRONG TEMPERATURE
GRADIENT. IFR CEILINGS AT KMOT AND KJMS EXPECTED TO EXPAND WESTWARD
INTO KBIS AND POSSIBLY KISN BETWEEN 06-12Z. DISTURBANCE MOVING
ACROSS THE AREA WILL ALSO BRING A CHANCE OF FREEZING RAIN OR MIXED
PRECIPITATION. KEPT A MENTION OF FREEZING RAIN AT KISN AND KBIS.
KDIK APPEARS TO BE WARM ENOUGH FOR ALL RAIN...WHILE PRECIPITATION
HAS A HARD TIME MAKING IT AS FAR EAST AS KMOT AND KJMS TONIGHT AND
BY SUNDAY MORNING IT SHOULD BE COLD ENOUGH FOR SNOW.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY UNTIL 6 AM CST SUNDAY FOR NDZ009-010-
017>021-048-051.
FREEZING RAIN ADVISORY UNTIL NOON CST SUNDAY FOR NDZ034>036-046-
047-050.
&&
$$
UPDATE...KS
SHORT TERM...AYD
LONG TERM...JV
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1236 PM EST SUN FEB 8 2015
.SYNOPSIS...
A LOW PRESSURE SYSTEM AND ASSOCIATED COLD FRONT WILL MOVE ACROSS
THE REGION TONIGHT INTO MONDAY MORNING. HIGH PRESSURE WILL THEN
SETTLE IN BEHIND THIS WEATHER SYSTEM MONDAY NIGHT INTO TUESDAY.
WARM TEMPERATURES TODAY WILL COOL BACK DOWN TO BELOW NORMAL READINGS
FOR THE FIRST PART OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A LOW PRESSURE SYSTEM NEAR NORTHERN INDIANA WILL MOVE
EAST/SOUTHEAST TO OUR WESTERN FORECAST AREA BY THIS EVENING.
MODELS CONTINUE TO ADVECT LOW LEVEL MOISTURE AHEAD OF THIS LOW TOO
FAST INTO OUR AREA AND THIS RESULT IS HAVING CONSEQUENCES IN TERMS
OF FORECASTING HIGH TEMPERATURES AND CHANCES FOR PRECIPITATION.
IN COMPARISON TO RECENT OBSERVATIONS...THE RAP MODEL SEEMS TO HAVE
THE BEST HANDLE ON THE INCREASING LOW LEVEL MOISTURE FROM THE
SOUTHWEST TODAY. AS A RESULT...HAVE CONTINUED TO DELAY ANY THREAT
FOR LIGHT RAIN UNTIL LATE AFTERNOON. GIVEN A WARM START THIS
MORNING AND HOW WARM IT WAS YESTERDAY...HAVE TAKEN A BLEND OF THE
ECMWF AND RAP TO COME UP WITH TODAYS HIGHS. ULTIMATELY...HOW WARM
IT GETS WILL DEPEND ON THE SPEED AND EXPANSION OF LOW LEVEL
CLOUDS. WILL RANGE HIGHS FROM THE LOWER 50S NORTH TO THE LOWER 60S
ALONG AND SOUTH OF THE OHIO RIVER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
OPERATIONAL MODELS ARE IN PRETTY GOOD AGREEMENT IN TERMS OF
PLACEMENT AND TIMING OF SYNOPTIC SCALE SYSTEMS THROUGH THE SHORT
TERM PERIOD. HAVE USED A BLEND OF THE NAM/GFS/ECMWF.
FOR TONIGHT...AN UPR LVL S/WV WILL INTERACT WITH LIMITED DEEP
MOISTURE AND FRONTAL CONVERGENCE TO BRING THE THREAT FOR LIGHT RAIN
TO THE REGION THIS EVENING. HAVE CONTINUED WITH LIKELY POPS ALONG
AND SOUTHEAST OF THE LOW AND ITS ASSOCIATED FRONT. AS THE LOW AND
FRONT CONTINUE TO MOVE SOUTHEAST OVERNIGHT...COLDER AIR WILL
GRADUALLY FILTER BACK INTO THE AREA FROM THE NORTH. SOME OF THE
WRAP AROUND MOISTURE MAY MIX WITH OR CHANGE TO SNOW ACROSS THE
NORTHWEST HALF CWFA BEFORE TAPERING OFF. LITTLE TO NO SNOW
ACCUMULATION IS EXPECTED.
ON MONDAY...LOW AND FRONT WILL MOVE EAST ALONG WITH THE THREAT OF
PRECIPITATION. COULD BE SOME LINGERING LIGHT RAIN AND/OR SNOW
SHOWERS IN THE EAST DURING THE MORNING. MODELS INDICATE THAT
CONSIDERABLE LOW LEVEL MOISTURE/CLOUDS WILL REMAIN OVER THE AREA
AND WILL FORECAST CLOUDY SKIES. HIGHS WILL BE TRICKY GIVEN SHALLOW
CAA INTO THE REGION AND RELATIVELY WARM START IN THE SOUTHEAST.
THIS WILL RESULT IN A DOWNWARD TREND IN TEMPS ACRS THE SOUTHEAST
DURING THE MORNING BEFORE STEADYING OUT WHILE THE NORTHERN
LOCATIONS SEE JUST A SMALL INCREASE IN HIGHS GIVEN CAA AND CLOUDY
SKIES.
FOR MONDAY NIGHT INTO TUESDAY...HIGH PRESSURE WILL BUILD SOUTHEAST
INTO THE GREAT LAKES AND OHIO VALLEY. MODEL SOUNDINGS INDICATE
THAT CLOUDS WILL BE SLOW TO CLEAR FROM NORTHWEST TO SOUTHEAST...BUT
ALL AREAS SHOULD BECOME MOSTLY CLEAR/MOSTLY SUNNY BY TUESDAY AFTERNOON.
TEMPERATURES WILL DROP BACK DOWN TO BELOW NORMAL READINGS FOR
EARLY FEBRUARY.
HIGH PRESSURE WILL MOVE EAST TUESDAY NIGHT AS MID AND HIGH LEVEL
CLOUDS MOVE IN FROM THE WEST AHEAD OF THE NEXT WEATHER SYSTEM FOR
WEDNESDAY/THURSDAY TIME FRAME.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
MODELS ARE IN DECENT AGREEMENT WITH SHORT WAVE ENERGY PUSHING
ACROSS THE SOUTHERN GREAT LAKES DURING THE DAY ON WEDNESDAY. THE
BEST FORCING WITH THIS WILL REMAIN TO OUR NORTH...BUT WE COULD
STILL SEE SOME ISOLATED TO SCATTERED SHOWER ACTIVITY WORK IN
ACROSS OUR NORTHERN AREAS THROUGH THE DAY. WAA OUT AHEAD OF THIS
WILL HELP PUSH HIGHS UP INTO THE UPPER 30S NORTH TO LOWER/MID 40S
IN THE SOUTH. AS A RESULT...WOULD EXPECT ANY PCPN TO BE EITHER A
RAIN/SNOW MIX OR RAIN THROUGH WEDNESDAY AFTERNOON. AS THE SHORT
WAVE MOVES OFF TO THE EAST...AN ASSOCIATED ARCTIC COLD FRONT WILL
PUSH SOUTH ACROSS OUR AREA WEDNESDAY NIGHT WITH A MUCH COLDER
AIRMASS SETTLING IN THROUGH THE DAY ON THURSDAY. LOWS WEDNESDAY
NIGHT WILL FALL INTO THE TEENS TO LOW/MID 20S...WITH LITTLE IN THE
WAY OF RECOVERY THROUGH THE DAY ON THURSDAY. AS WE GET INTO SOME
CYCLONIC LOW LEVEL FLOW AND DEVELOP A FETCH OFF OF LAKE
MICHIGAN...EXPECT TO SEE SOME ISOLATED TO SCATTERED SNOW SHOWER
ACTIVITY LATER WEDNESDAY NIGHT AND INTO THURSDAY.
DRY BUT CONTINUED COLD CONDITIONS ARE EXPECTED FOR FRIDAY AS HIGH
PRESSURE BUILDS BACK INTO THE AREA. HIGHS ON FRIDAY WILL GENERALLY
BE IN THE 20S. IT LOOKS LIKE A WEAK CLIPPER TYPE SYSTEM MAY DROP
DOWN TOWARD THE AREA NEXT WEEKEND. HOWEVER...TIMING AND PLACEMENT
HAVE VARIED OVER THE LAST COUPLE OF RUNS OF THE GFS AND ECMWF SO
WILL LIMIT POPS TO 20 PERCENT OR LESS THROUGH THE END OF THE LONG
TERM PERIOD.
&&
.AVIATION /18Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS AT THE VERY START WILL SOON GIVE WAY TO MVFR AS LOW
LEVEL MOISTURE CONVERGES TO FORM CEILINGS AHEAD OF LOW PRESSURE.
LIGHT RAIN IS EXPECTED TO DEVELOP THIS EVENING AS THE LOW MOVES INTO
OHIO. THERE MAY BE A PERIOD OF IFR CEILINGS LATER TONIGHT AT
NORTHERN TAF SITES DAY ILN CMH AND LCK. SOUTHWEST WINDS GUSTING
OVER 20 KNOTS WILL SHIFT TO NORTHWEST BEHIND THE LOW. RAIN WILL
DIMINISH BY MONDAY LEAVING MVFR CEILINGS IN PERSISTENT LOW LEVEL
MOISTURE.
OUTLOOK...MVFR CEILINGS MAY CONTINUE INTO WEDNESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HICKMAN
NEAR TERM...CONIGLIO/HICKMAN
SHORT TERM...HICKMAN
LONG TERM...JGL
AVIATION...CONIGLIO
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
947 AM EST SUN FEB 8 2015
.SYNOPSIS...
LOW PRESSURE WILL SLIDE SOUTHEAST ACROSS OHIO TODAY THEN PULL A COLD
FRONT SOUTH ACROSS THE AREA AS IT CONTINUES TO THE EAST COAST ON
MONDAY. HIGH PRESSURE WILL BUILD EAST ACROSS THE GREAT LAKES REGION
ON TUESDAY. A BROAD AREA OF LOW PRESSURE WILL MOVE OVER THE AREA ON
WEDNESDAY FOLLOWED BY AN ARCTIC COLD FRONT ON THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HAVE ONLY ADJUSTED HOURLY TEMPERATURES WITH THIS UPDATE. PREVIOUS
CONCERNS ABOUT THE LOCATION OF THE FRONTAL BOUNDARY REMAIN. AS OF
14Z THE FRONTAL BOUNDARY WAS LOCATED FROM SOUTH OF BUFFALO TO
DUNKIRK THEN FOLLOWING A RIDGELINE JUST INLAND OF LAKE ERIE INTO
EXTREME NORTHEASTERN ASHTABULA COUNTY. THIS BOUNDARY HAS CREATED
LARGE TEMPERATURE DIFFERENCES ACROSS NORTHERN ERIE COUNTY PA WITH
LOCATIONS WEST AND NORTH OF INTERSTATE 90 RANGING FROM NEAR 30 TO
THE MID 30S. SOUTH OF THE BOUNDARY TEMPERATURES WERE IN THE LOWER
40S.
THE LOCATION OF THIS BOUNDARY WILL BE CRITICAL WHEN THE LIGHT
PRECIPITATION ARRIVES THIS AFTERNOON INTO THE EVENING. IF IT
REMAINS ENTRENCHED WHERE IT IS THERE COULD BE A LONGER PERIOD OF
FREEZING DRIZZLE BEFORE THE SNOW BEGINS. WE WILL MONITOR THIS
CLOSELY THROUGH THE AFTERNOON.
PREVIOUS DISCUSSION...A BROAD AREA OF LOW PRESSURE IS IN PLACE NEAR
CHICAGO THIS MORNING WITH A STATIONARY FRONT EXTENDING EAST ACROSS
LAKE ERIE. VERY WARM AIR IS IN PLACE TO THE SOUTH WITH
TEMPERATURES NEAR 50 DEGREES ALREADY IN SOUTHERN INDIANA/OHIO.
HAVE RAISED HIGHS SEVERAL DEGREES FOR TODAY(MID 40S NORTH TO LOW
50S SOUTH) AS TEMPERATURES CONTINUE TO WARM INTO EARLY AFTERNOON
BEFORE CLOUDS THICKEN ENOUGH TO SLOW THE WARMING. THE HRRR SHOWS
THE STRATUS FINALLY FILLING IN EARLY THIS AFTERNOON BUT WILL HAVE
PLENTY OF HIGH CLOUD AROUND PRIOR TO THAT. MODELS HAVE BEEN TOO
MOIST OVER THE LAST DAY AND HAVE DELAYED THE MENTION OF DRIZZLE OR
LIGHT RAIN UNTIL MID AFTERNOON WHEN LOW LEVEL ISENTROPIC ASCENT
RAMPS UP IMMEDIATELY AHEAD OF THE APPROACHING LOW.
SNOWPACK WILL GRADUALLY START TO MELT TODAY BUT NOT EXPECTING ENOUGH
WATER TO BE RELEASED TO CAUSE FLOODING PROBLEMS. THE GFS HAS REALLY
BEEN STRUGGLING WITH TOO MUCH LOW LEVEL MOISTURE AND ALREADY HAS
PRECIPITATION BLOSSOMING BY SUNRISE. WENT MORE WITH A NAM/ECMWF
BLEND FOR QPF WHICH HAS UP TO A TENTH OF AN INCH OF QPF
TODAY...WITH MOST AREAS SEEING LESS THAN A QUARTER INCH THROUGH
MONDAY MORNING...SLIGHTLY HIGHER IN NW PA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
AS THE UPPER LEVEL TROUGH DEEPENS OVERHEAD TONIGHT...THE LOW WILL
TRACK SOUTHEAST TOWARDS WEST VIRGINIA. AS THE LOW SLIDES TO THE
SOUTHEAST...COLDER AIR IN PLACE NORTH OF LAKE ERIE WILL BE PULLED
SOUTH OVER THE AREA. THIS DOES CREATE A CONCERN FOR PRECIP TYPE
TONIGHT...DESPITE THE WARM SURFACE TEMPERATURES TODAY. MODELS HAVE
BEEN SHOWING WINDS SWITCHING AROUND TO THE NE AT ERI WITH
TEMPERATURES FALLING TO NEAR OR BELOW FREEZING BY 01Z. A WARM
LAYER OF AIR WILL REMAIN ALOFT AS THE SURFACE STARTS TO COOL SO A
PERIOD OF FREEZING RAIN WILL BE POSSIBLE. THE AREA MOST LIKELY TO
EXPERIENCE FREEZING RAIN TONIGHT IS IN NE OH/NW PA BEFORE THE
COLUMN COOLS SUFFICIENTLY TO SWITCH OVER TO SNOW. ALTHOUGH
FREEZING RAIN IS IN THE FORECAST...IT WILL LIKELY BE LIGHT...WITH
SOME UNCERTAINTY STILL WITH SURFACE TEMPERATURES FOLLOWING THE
WARM AFTERNOON. HAVE DECIDED TO HOLD OFF ON ISSUING A FREEZING
RAIN OR WINTER WEATHER ADVISORY ALTHOUGH ONE MAY BE NEEDED
TONIGHT. CONFIDENCE WAS NOT THERE AT THIS TIME SO WILL ALLOW DAY
SHIFT TO TAKE ANOTHER LOOK AT THERMAL PROFILES AND PRECIPITATION
TIMING TODAY.
ALL SITES SHOULD BRIEFLY TRANSITION OVER TO SNOW AS THE COLD FRONT
IS PULLED SOUTH BUT ACCUMULATIONS WILL GENERALLY BE AN INCH OR LESS.
DID LEAVE A CHANCE OF SNOW SHOWERS IN THE FORECAST FOR MONDAY
ALTHOUGH DEEPER MOISTURE WILL QUICKLY PULL AWAY TO THE EAST. HIGHS
ON MONDAY WILL BE BACK IN THE MID 20S.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AFTER A BRIEF WARM UP ON WEDNESDAY MORE COLD WEATHER WILL MOVE BACK
IN FOR THE LATTER PART OF THE WEEK AND NEXT WEEKEND.
A RIDGE WILL MOVE ACROSS THE FORECAST AREA ON TUESDAY AND THEN A
FRONT WITH A LOW WILL MOVE THROUGH STARTING WEDNESDAY. THIS PART OF
THE EVENT LOOKS LIKE CHANCE POPS. SOME QUESTION ON THE PRECIPITATION
MAINLY SOUTH OF US 30...RAIN OR SNOW IS POSSIBLE. AS THE LOW SLIDES
SOUTHEAST INTO PENNSYLVANIA...COLDER AIR WILL START COMING IN FROM
THE NORTHWEST. THE WIND DIRECTION SHIFTS AROUND...MOISTURE IS
ADEQUATE...PLENTY OF COLD AIR AT 850 MB...-20C AND COLDER. WILL
MENTION A THREAT IN THE HAZARDOUS WEATHER OUTLOOK MAINLY FOR
ASHTABULA AND NW PA. HIGH PRESSURE WILL START BUILDING IN ON
FRIDAY...SOME SNOW SHOWERS COULD LINGER OVER NW PA EARLY FRIDAY.
ANOTHER FRONTAL SYSTEM WILL BE MOVING IN LATE FRIDAY NIGHT THROUGH
SATURDAY NIGHT WITH CHANCE POPS LOOKING REASONABLE AT THIS TIME.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
A FRONTAL BOUNDARY WITH A LOW MOVING ON IT WILL BE SINKING INTO
THE AREA FROM THE NORTH. AT 11Z THIS FRONT HAD SLIPPED INTO ERI.
SOME QUESTION IF IT WOULD PUSH NORTH THIS MORNING AS THE LOW
DEVELOPS ON THE FRONT. NONE THE LESS THE TREND ACROSS THE FORECAST
AREA TODAY WILL BE FOR LOWERING CONDITIONS...EVENTUALLY TO IFR.
THE QUESTION IS HOW QUICKLY WILL THIS OCCUR AND WHEN WILL SOME
DRIZZLE DEVELOP AND THEN EVENTUALLY SWITCHED TO FREEZING DRIZZLE
OR FREEZING RAIN AND THEN TO SNOW.
.OUTLOOK...NON VFR MONDAY AND MONDAY EVENING. NON VFR DEVELOPING
WEDNESDAY AND CONTINUING INTO THURSDAY.
&&
.MARINE...
NO GALE FORCE WINDS ARE EXPECTED ON LAKE ERIE THROUGH THE FORECAST
PERIOD.
A FRONTAL SYSTEM WITH A LOW MOVING ALONG IT WILL BE THE WEATHER
MAKER ON LAKE ERIE FOR THE NEXT COUPLE OF DAYS. WINDS SHOULD REMAIN
BELOW 20 KNOTS. THEY SHOULD BE STRONGEST LATE SUNDAY NIGHT AS THE
LOW MOVES THROUGH PENNSYLVANIA. HIGH PRESSURE WILL THEN BUILD OVER
THE LAKE ON TUESDAY AND THEN ANOTHER DIFFUSE FRONTAL SYSTEM WILL
AFFECT THE LAKE WEDNESDAY AND WEDNESDAY NIGHT. AS THE LOW MOVES AWAY
WEDNESDAY NIGHT THE NORTH TO NORTHWEST FLOW WILL GET STRONGER BUT
REMAIN WELL BELOW GALE FORCE IN THE MODERATE TO STRONG COLD
ADVECTION. HIGH PRESSURE WILL BUILD IN BY FRIDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...KEC/MULLEN
SHORT TERM...KEC
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
923 AM EST SUN FEB 8 2015
.SYNOPSIS...
A LOW PRESSURE SYSTEM AND ASSOCIATED COLD FRONT WILL MOVE ACROSS
THE REGION TONIGHT INTO MONDAY MORNING. HIGH PRESSURE WILL THEN
SETTLE IN BEHIND THIS WEATHER SYSTEM MONDAY NIGHT INTO TUESDAY.
WARM TEMPERATURES TODAY WILL COOL BACK DOWN TO BELOW NORMAL READINGS
FOR THE FIRST PART OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A LOW PRESSURE SYSTEM NEAR NORTHERN INDIANA WILL MOVE
EAST/SOUTHEAST TO OUR WESTERN FORECAST AREA BY THIS EVENING.
MODELS CONTINUE TO ADVECT LOW LEVEL MOISTURE AHEAD OF THIS LOW TOO
FAST INTO OUR AREA AND THIS RESULT IS HAVING CONSEQUENCES IN TERMS
OF FORECASTING HIGH TEMPERATURES AND CHANCES FOR PRECIPITATION.
IN COMPARISON TO RECENT OBSERVATIONS...THE RAP MODEL SEEMS TO HAVE
THE BEST HANDLE ON THE INCREASING LOW LEVEL MOISTURE FROM THE
SOUTHWEST TODAY. AS A RESULT...HAVE CONTINUED TO DELAY ANY THREAT
FOR LIGHT RAIN UNTIL LATE AFTERNOON. GIVEN A WARM START THIS
MORNING AND HOW WARM IT WAS YESTERDAY...HAVE TAKEN A BLEND OF THE
ECMWF AND RAP TO COME UP WITH TODAYS HIGHS. ULTIMATELY...HOW WARM
IT GETS WILL DEPEND ON THE SPEED AND EXPANSION OF LOW LEVEL
CLOUDS. WILL RANGE HIGHS FROM THE LOWER 50S NORTH TO THE LOWER 60S
ALONG AND SOUTH OF THE OHIO RIVER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
OPERATIONAL MODELS ARE IN PRETTY GOOD AGREEMENT IN TERMS OF
PLACEMENT AND TIMING OF SYNOPTIC SCALE SYSTEMS THROUGH THE SHORT
TERM PERIOD. HAVE USED A BLEND OF THE NAM/GFS/ECMWF.
FOR TONIGHT...AN UPR LVL S/WV WILL INTERACT WITH LIMITED DEEP
MOISTURE AND FRONTAL CONVERGENCE TO BRING THE THREAT FOR LIGHT RAIN
TO THE REGION THIS EVENING. HAVE CONTINUED WITH LIKELY POPS ALONG
AND SOUTHEAST OF THE LOW AND ITS ASSOCIATED FRONT. AS THE LOW AND
FRONT CONTINUE TO MOVE SOUTHEAST OVERNIGHT...COLDER AIR WILL
GRADUALLY FILTER BACK INTO THE AREA FROM THE NORTH. SOME OF THE
WRAP AROUND MOISTURE MAY MIX WITH OR CHANGE TO SNOW ACROSS THE
NORTHWEST HALF CWFA BEFORE TAPERING OFF. LITTLE TO NO SNOW
ACCUMULATION IS EXPECTED.
ON MONDAY...LOW AND FRONT WILL MOVE EAST ALONG WITH THE THREAT OF
PRECIPITATION. COULD BE SOME LINGERING LIGHT RAIN AND/OR SNOW
SHOWERS IN THE EAST DURING THE MORNING. MODELS INDICATE THAT
CONSIDERABLE LOW LEVEL MOISTURE/CLOUDS WILL REMAIN OVER THE AREA
AND WILL FORECAST CLOUDY SKIES. HIGHS WILL BE TRICKY GIVEN SHALLOW
CAA INTO THE REGION AND RELATIVELY WARM START IN THE SOUTHEAST.
THIS WILL RESULT IN A DOWNWARD TREND IN TEMPS ACRS THE SOUTHEAST
DURING THE MORNING BEFORE STEADYING OUT WHILE THE NORTHERN
LOCATIONS SEE JUST A SMALL INCREASE IN HIGHS GIVEN CAA AND CLOUDY
SKIES.
FOR MONDAY NIGHT INTO TUESDAY...HIGH PRESSURE WILL BUILD SOUTHEAST
INTO THE GREAT LAKES AND OHIO VALLEY. MODEL SOUNDINGS INDICATE
THAT CLOUDS WILL BE SLOW TO CLEAR FROM NORTHWEST TO SOUTHEAST...BUT
ALL AREAS SHOULD BECOME MOSTLY CLEAR/MOSTLY SUNNY BY TUESDAY AFTERNOON.
TEMPERATURES WILL DROP BACK DOWN TO BELOW NORMAL READINGS FOR
EARLY FEBRUARY.
HIGH PRESSURE WILL MOVE EAST TUESDAY NIGHT AS MID AND HIGH LEVEL
CLOUDS MOVE IN FROM THE WEST AHEAD OF THE NEXT WEATHER SYSTEM FOR
WEDNESDAY/THURSDAY TIME FRAME.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
MODELS ARE IN DECENT AGREEMENT WITH SHORT WAVE ENERGY PUSHING
ACROSS THE SOUTHERN GREAT LAKES DURING THE DAY ON WEDNESDAY. THE
BEST FORCING WITH THIS WILL REMAIN TO OUR NORTH...BUT WE COULD
STILL SEE SOME ISOLATED TO SCATTERED SHOWER ACTIVITY WORK IN
ACROSS OUR NORTHERN AREAS THROUGH THE DAY. WAA OUT AHEAD OF THIS
WILL HELP PUSH HIGHS UP INTO THE UPPER 30S NORTH TO LOWER/MID 40S
IN THE SOUTH. AS A RESULT...WOULD EXPECT ANY PCPN TO BE EITHER A
RAIN/SNOW MIX OR RAIN THROUGH WEDNESDAY AFTERNOON. AS THE SHORT
WAVE MOVES OFF TO THE EAST...AN ASSOCIATED ARCTIC COLD FRONT WILL
PUSH SOUTH ACROSS OUR AREA WEDNESDAY NIGHT WITH A MUCH COLDER
AIRMASS SETTLING IN THROUGH THE DAY ON THURSDAY. LOWS WEDNESDAY
NIGHT WILL FALL INTO THE TEENS TO LOW/MID 20S...WITH LITTLE IN THE
WAY OF RECOVERY THROUGH THE DAY ON THURSDAY. AS WE GET INTO SOME
CYCLONIC LOW LEVEL FLOW AND DEVELOP A FETCH OFF OF LAKE
MICHIGAN...EXPECT TO SEE SOME ISOLATED TO SCATTERED SNOW SHOWER
ACTIVITY LATER WEDNESDAY NIGHT AND INTO THURSDAY.
DRY BUT CONTINUED COLD CONDITIONS ARE EXPECTED FOR FRIDAY AS HIGH
PRESSURE BUILDS BACK INTO THE AREA. HIGHS ON FRIDAY WILL GENERALLY
BE IN THE 20S. IT LOOKS LIKE A WEAK CLIPPER TYPE SYSTEM MAY DROP
DOWN TOWARD THE AREA NEXT WEEKEND. HOWEVER...TIMING AND PLACEMENT
HAVE VARIED OVER THE LAST COUPLE OF RUNS OF THE GFS AND ECMWF SO
WILL LIMIT POPS TO 20 PERCENT OR LESS THROUGH THE END OF THE LONG
TERM PERIOD.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
SOUTHWESTERLY WINDS WILL CONTINUE TO INCREASE IN STRENGTH THROUGH
THE MORNING HOURS...WITH OCCASIONAL GUSTS OF AROUND 20 KNOTS.
MOISTURE WILL GRADUALLY INCREASE AHEAD OF A COLD FRONT...WITH MVFR
CEILINGS BECOMING MORE COMMON BY EARLY AFTERNOON. DURING THE
EVENING...SOME AREAS OF LIGHT RAIN ARE EXPECTED TO DEVELOP. THIS
RAIN IS UNLIKELY TO HAVE A SIGNIFICANT ADDITIONAL IMPACT ON
AVIATION CONDITIONS...BUT CEILINGS WILL CONTINUE TO LOWER EVEN
OUTSIDE OF THE RAIN...WITH LOW-END MVFR (AND POSSIBLY IFR)
CONDITIONS EXPECTED FOR THE SECOND HALF OF THE FORECAST PERIOD.
RAIN IS EXPECTED TO COME TO AN END DURING THE OVERNIGHT
HOURS...ALTHOUGH THERE IS A CHANCE THAT SOME VERY LIGHT
RAIN/DRIZZLE/FLURRIES COULD CONTINUE INTO MONDAY MORNING. CEILINGS
MAY BEGIN TO GRADUALLY IMPROVE BEHIND THE COLD FRONT...BUT THIS
IMPROVEMENT WILL NOT BE QUICK. WINDS BEHIND THE FRONT WILL SHIFT
TO THE NORTH...WITH SUSTAINED VALUES OF 10-15 KNOTS EXPECTED.
OUTLOOK...MVFR CEILINGS WILL LIKELY CONTINUE THROUGH THE DAY ON
MONDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HICKMAN
NEAR TERM...CONIGLIO/HICKMAN
SHORT TERM...HICKMAN
LONG TERM...JGL
AVIATION...HATZOS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
711 AM EST SUN FEB 8 2015
.SYNOPSIS...
LOW PRESSURE WILL SLIDE SOUTHEAST ACROSS OHIO TODAY THEN PULL A COLD
FRONT SOUTH ACROSS THE AREA AS IT CONTINUES TO THE EAST COAST ON
MONDAY. HIGH PRESSURE WILL BUILD EAST ACROSS THE GREAT LAKES REGION
ON TUESDAY. A BROAD AREA OF LOW PRESSURE WILL MOVE OVER THE AREA ON
WEDNESDAY FOLLOWED BY AN ARCTIC COLD FRONT ON THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS LOW PRESSURE APPROACHES FROM THE WEST THE TROUGH HAS BEEN
TIGHTENING UP ACROSS LAKE ERIE. THE TEMPERATURE AT ERI HAS DROPPED
TO 31 DEGREES WITH A WIND OUT OF THE NORTHEAST. VERY DIFFICULT TO
DETERMINE IF THEY WILL STAY OUT OF THE NORTHEAST AND BE COOL ALL
DAY OR IF THEY BRIEFLY SHIFT TO EAST OR SOUTHEAST AND WARM INTO
THE MID 30S. LOWERED HIGHS BY ABOUT 8 DEGREES IN ERIE PA. FREEZING
RAIN COULD BE MORE OF A CONCERN BY MID TO LATE AFTERNOON IF A COOL
NORTHEASTERLY WIND PERSISTS. ADJUSTED HOURLY TEMPERATURES...ACROSS
THE WHOLE AREA.
PREVIOUS DISCUSSION...A BROAD AREA OF LOW PRESSURE IS IN PLACE NEAR
CHICAGO THIS MORNING WITH A STATIONARY FRONT EXTENDING EAST ACROSS
LAKE ERIE. VERY WARM AIR IS IN PLACE TO THE SOUTH WITH
TEMPERATURES NEAR 50 DEGREES ALREADY IN SOUTHERN INDIANA/OHIO.
HAVE RAISED HIGHS SEVERAL DEGREES FOR TODAY(MID 40S NORTH TO LOW
50S SOUTH) AS TEMPERATURES CONTINUE TO WARM INTO EARLY AFTERNOON
BEFORE CLOUDS THICKEN ENOUGH TO SLOW THE WARMING. THE HRRR SHOWS
THE STRATUS FINALLY FILLING IN EARLY THIS AFTERNOON BUT WILL HAVE
PLENTY OF HIGH CLOUD AROUND PRIOR TO THAT. MODELS HAVE BEEN TOO
MOIST OVER THE LAST DAY AND HAVE DELAYED THE MENTION OF DRIZZLE OR
LIGHT RAIN UNTIL MID AFTERNOON WHEN LOW LEVEL ISENTROPIC ASCENT
RAMPS UP IMMEDIATELY AHEAD OF THE APPROACHING LOW.
SNOWPACK WILL GRADUALLY START TO MELT TODAY BUT NOT EXPECTING ENOUGH
WATER TO BE RELEASED TO CAUSE FLOODING PROBLEMS. THE GFS HAS REALLY
BEEN STRUGGLING WITH TOO MUCH LOW LEVEL MOISTURE AND ALREADY HAS
PRECIPITATION BLOSSOMING BY SUNRISE. WENT MORE WITH A NAM/ECMWF
BLEND FOR QPF WHICH HAS UP TO A TENTH OF AN INCH OF QPF
TODAY...WITH MOST AREAS SEEING LESS THAN A QUARTER INCH THROUGH
MONDAY MORNING...SLIGHTLY HIGHER IN NW PA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
AS THE UPPER LEVEL TROUGH DEEPENS OVERHEAD TONIGHT...THE LOW WILL
TRACK SOUTHEAST TOWARDS WEST VIRGINIA. AS THE LOW SLIDES TO THE
SOUTHEAST...COLDER AIR IN PLACE NORTH OF LAKE ERIE WILL BE PULLED
SOUTH OVER THE AREA. THIS DOES CREATE A CONCERN FOR PRECIP TYPE
TONIGHT...DESPITE THE WARM SURFACE TEMPERATURES TODAY. MODELS HAVE
BEEN SHOWING WINDS SWITCHING AROUND TO THE NE AT ERI WITH
TEMPERATURES FALLING TO NEAR OR BELOW FREEZING BY 01Z. A WARM
LAYER OF AIR WILL REMAIN ALOFT AS THE SURFACE STARTS TO COOL SO A
PERIOD OF FREEZING RAIN WILL BE POSSIBLE. THE AREA MOST LIKELY TO
EXPERIENCE FREEZING RAIN TONIGHT IS IN NE OH/NW PA BEFORE THE
COLUMN COOLS SUFFICIENTLY TO SWITCH OVER TO SNOW. ALTHOUGH
FREEZING RAIN IS IN THE FORECAST...IT WILL LIKELY BE LIGHT...WITH
SOME UNCERTAINTY STILL WITH SURFACE TEMPERATURES FOLLOWING THE
WARM AFTERNOON. HAVE DECIDED TO HOLD OFF ON ISSUING A FREEZING
RAIN OR WINTER WEATHER ADVISORY ALTHOUGH ONE MAY BE NEEDED
TONIGHT. CONFIDENCE WAS NOT THERE AT THIS TIME SO WILL ALLOW DAY
SHIFT TO TAKE ANOTHER LOOK AT THERMAL PROFILES AND PRECIPITATION
TIMING TODAY.
ALL SITES SHOULD BRIEFLY TRANSITION OVER TO SNOW AS THE COLD FRONT
IS PULLED SOUTH BUT ACCUMULATIONS WILL GENERALLY BE AN INCH OR LESS.
DID LEAVE A CHANCE OF SNOW SHOWERS IN THE FORECAST FOR MONDAY
ALTHOUGH DEEPER MOISTURE WILL QUICKLY PULL AWAY TO THE EAST. HIGHS
ON MONDAY WILL BE BACK IN THE MID 20S.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AFTER A BRIEF WARM UP ON WEDNESDAY MORE COLD WEATHER WILL MOVE BACK
IN FOR THE LATTER PART OF THE WEEK AND NEXT WEEKEND.
A RIDGE WILL MOVE ACROSS THE FORECAST AREA ON TUESDAY AND THEN A
FRONT WITH A LOW WILL MOVE THROUGH STARTING WEDNESDAY. THIS PART OF
THE EVENT LOOKS LIKE CHANCE POPS. SOME QUESTION ON THE PRECIPITATION
MAINLY SOUTH OF US 30...RAIN OR SNOW IS POSSIBLE. AS THE LOW SLIDES
SOUTHEAST INTO PENNSYLVANIA...COLDER AIR WILL START COMING IN FROM
THE NORTHWEST. THE WIND DIRECTION SHIFTS AROUND...MOISTURE IS
ADEQUATE...PLENTY OF COLD AIR AT 850 MB...-20C AND COLDER. WILL
MENTION A THREAT IN THE HAZARDOUS WEATHER OUTLOOK MAINLY FOR
ASHTABULA AND NW PA. HIGH PRESSURE WILL START BUILDING IN ON
FRIDAY...SOME SNOW SHOWERS COULD LINGER OVER NW PA EARLY FRIDAY.
ANOTHER FRONTAL SYSTEM WILL BE MOVING IN LATE FRIDAY NIGHT THROUGH
SATURDAY NIGHT WITH CHANCE POPS LOOKING REASONABLE AT THIS TIME.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
A FRONTAL BOUNDARY WITH A LOW MOVING ON IT WILL BE SINKING INTO
THE AREA FROM THE NORTH. AT 11Z THIS FRONT HAD SLIPPED INTO ERI.
SOME QUESTION IF IT WOULD PUSH NORTH THIS MORNING AS THE LOW
DEVELOPS ON THE FRONT. NONE THE LESS THE TREND ACROSS THE FORECAST
AREA TODAY WILL BE FOR LOWERING CONDITIONS...EVENTUALLY TO IFR.
THE QUESTION IS HOW QUICKLY WILL THIS OCCUR AND WHEN WILL SOME
DRIZZLE DEVELOP AND THEN EVENTUALLY SWITCHED TO FREEZING DRIZZLE
OR FREEZING RAIN AND THEN TO SNOW.
.OUTLOOK...NON VFR MONDAY AND MONDAY EVENING. NON VFR DEVELOPING
WEDNESDAY AND CONTINUING INTO THURSDAY.
&&
.MARINE...
NO GALE FORCE WINDS ARE EXPECTED ON LAKE ERIE THROUGH THE FORECAST
PERIOD.
A FRONTAL SYSTEM WITH A LOW MOVING ALONG IT WILL BE THE WEATHER
MAKER ON LAKE ERIE FOR THE NEXT COUPLE OF DAYS. WINDS SHOULD REMAIN
BELOW 20 KNOTS. THEY SHOULD BE STRONGEST LATE SUNDAY NIGHT AS THE
LOW MOVES THROUGH PENNSYLVANIA. HIGH PRESSURE WILL THEN BUILD OVER
THE LAKE ON TUESDAY AND THEN ANOTHER DIFFUSE FRONTAL SYSTEM WILL
AFFECT THE LAKE WEDNESDAY AND WEDNESDAY NIGHT. AS THE LOW MOVES AWAY
WEDNESDAY NIGHT THE NORTH TO NORTHWEST FLOW WILL GET STRONGER BUT
REMAIN WELL BELOW GALE FORCE IN THE MODERATE TO STRONG COLD
ADVECTION. HIGH PRESSURE WILL BUILD IN BY FRIDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...KEC
SHORT TERM...KEC
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
639 AM EST SUN FEB 8 2015
.SYNOPSIS...
A LOW PRESSURE SYSTEM AND ASSOCIATED COLD FRONT WILL MOVE ACROSS
THE REGION TONIGHT INTO MONDAY MORNING. HIGH PRESSURE WILL THEN
SETTLE IN BEHIND THIS WEATHER SYSTEM MONDAY NIGHT INTO TUESDAY.
WARM TEMPERATURES TODAY WILL COOL BACK DOWN TO BELOW NORMAL READINGS
FOR THE FIRST PART OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A LOW PRESSURE SYSTEM NEAR NORTHERN ILLINOIS THIS MORNING WILL
MOVE EAST/SOUTHEAST TO OUR WESTERN FORECAST AREA BY THIS EVENING.
MODELS CONTINUE TO ADVECT LOW LEVEL MOISTURE AHEAD OF THIS LOW TOO
FAST INTO OUR AREA AND THIS RESULT IS HAVING CONSEQUENCES IN
TERMS OF FORECASTING HIGH TEMPERATURES AND CHANCES FOR PRECIPITATION.
THE RAP MODEL SEEMS TO HAVE THE BEST HANDLE ON THE INCREASING LOW
LEVEL MOISTURE FROM THE SOUTHWEST TODAY. AS A RESULT...HAVE
DELAYED ANY THREAT FOR LIGHT RAIN UNTIL LATE AFTERNOON. GIVEN A
WARM START THIS MORNING AND HOW WARM IT WAS YESTERDAY...HAVE TAKEN
A BLEND OF THE ECMWF AND RAP TO COME UP WITH TODAYS HIGHS.
ULTIMATELY...HOW WARM IT GETS WILL DEPEND ON THE SPEED AND
EXPANSION OF LOW LEVEL CLOUDS. WILL RANGE HIGHS FROM THE LOWER 50S
NORTH TO THE LOWER 60S ALONG AND SOUTH OF THE OHIO RIVER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
OPERATIONAL MODELS ARE IN PRETTY GOOD AGREEMENT IN TERMS OF
PLACEMENT AND TIMING OF SYNOPTIC SCALE SYSTEMS THROUGH THE SHORT
TERM PERIOD. HAVE USED A BLEND OF THE NAM/GFS/ECMWF.
FOR TONIGHT...AN UPR LVL S/WV WILL INTERACT WITH LIMITED DEEP
MOISTURE AND FRONTAL CONVERGENCE TO BRING THE THREAT FOR LIGHT RAIN
TO THE REGION THIS EVENING. HAVE CONTINUED WITH LIKELY POPS ALONG
AND SOUTHEAST OF THE LOW AND ITS ASSOCIATED FRONT. AS THE LOW AND
FRONT CONTINUE TO MOVE SOUTHEAST OVERNIGHT...COLDER AIR WILL
GRADUALLY FILTER BACK INTO THE AREA FROM THE NORTH. SOME OF THE
WRAP AROUND MOISTURE MAY MIX WITH OR CHANGE TO SNOW ACROSS THE
NORTHWEST HALF CWFA BEFORE TAPERING OFF. LITTLE TO NO SNOW
ACCUMULATION IS EXPECTED.
ON MONDAY...LOW AND FRONT WILL MOVE EAST ALONG WITH THE THREAT OF
PRECIPITATION. COULD BE SOME LINGERING LIGHT RAIN AND/OR SNOW
SHOWERS IN THE EAST DURING THE MORNING. MODELS INDICATE THAT
CONSIDERABLE LOW LEVEL MOISTURE/CLOUDS WILL REMAIN OVER THE AREA
AND WILL FORECAST CLOUDY SKIES. HIGHS WILL BE TRICKY GIVEN SHALLOW
CAA INTO THE REGION AND RELATIVELY WARM START IN THE SOUTHEAST.
THIS WILL RESULT IN A DOWNWARD TREND IN TEMPS ACRS THE SOUTHEAST
DURING THE MORNING BEFORE STEADYING OUT WHILE THE NORTHERN
LOCATIONS SEE JUST A SMALL INCREASE IN HIGHS GIVEN CAA AND CLOUDY
SKIES.
FOR MONDAY NIGHT INTO TUESDAY...HIGH PRESSURE WILL BUILD SOUTHEAST
INTO THE GREAT LAKES AND OHIO VALLEY. MODEL SOUNDINGS INDICATE
THAT CLOUDS WILL BE SLOW TO CLEAR FROM NORTHWEST TO SOUTHEAST...BUT
ALL AREAS SHOULD BECOME MOSTLY CLEAR/MOSTLY SUNNY BY TUESDAY AFTERNOON.
TEMPERATURES WILL DROP BACK DOWN TO BELOW NORMAL READINGS FOR
EARLY FEBRUARY.
HIGH PRESSURE WILL MOVE EAST TUESDAY NIGHT AS MID AND HIGH LEVEL
CLOUDS MOVE IN FROM THE WEST AHEAD OF THE NEXT WEATHER SYSTEM FOR
WEDNESDAY/THURSDAY TIME FRAME.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
MODELS ARE IN DECENT AGREEMENT WITH SHORT WAVE ENERGY PUSHING
ACROSS THE SOUTHERN GREAT LAKES DURING THE DAY ON WEDNESDAY. THE
BEST FORCING WITH THIS WILL REMAIN TO OUR NORTH...BUT WE COULD
STILL SEE SOME ISOLATED TO SCATTERED SHOWER ACTIVITY WORK IN
ACROSS OUR NORTHERN AREAS THROUGH THE DAY. WAA OUT AHEAD OF THIS
WILL HELP PUSH HIGHS UP INTO THE UPPER 30S NORTH TO LOWER/MID 40S
IN THE SOUTH. AS A RESULT...WOULD EXPECT ANY PCPN TO BE EITHER A
RAIN/SNOW MIX OR RAIN THROUGH WEDNESDAY AFTERNOON. AS THE SHORT
WAVE MOVES OFF TO THE EAST...AN ASSOCIATED ARCTIC COLD FRONT WILL
PUSH SOUTH ACROSS OUR AREA WEDNESDAY NIGHT WITH A MUCH COLDER
AIRMASS SETTLING IN THROUGH THE DAY ON THURSDAY. LOWS WEDNESDAY
NIGHT WILL FALL INTO THE TEENS TO LOW/MID 20S...WITH LITTLE IN THE
WAY OF RECOVERY THROUGH THE DAY ON THURSDAY. AS WE GET INTO SOME
CYCLONIC LOW LEVEL FLOW AND DEVELOP A FETCH OFF OF LAKE
MICHIGAN...EXPECT TO SEE SOME ISOLATED TO SCATTERED SNOW SHOWER
ACTIVITY LATER WEDNESDAY NIGHT AND INTO THURSDAY.
DRY BUT CONTINUED COLD CONDITIONS ARE EXPECTED FOR FRIDAY AS HIGH
PRESSURE BUILDS BACK INTO THE AREA. HIGHS ON FRIDAY WILL GENERALLY
BE IN THE 20S. IT LOOKS LIKE A WEAK CLIPPER TYPE SYSTEM MAY DROP
DOWN TOWARD THE AREA NEXT WEEKEND. HOWEVER...TIMING AND PLACEMENT
HAVE VARIED OVER THE LAST COUPLE OF RUNS OF THE GFS AND ECMWF SO
WILL LIMIT POPS TO 20 PERCENT OR LESS THROUGH THE END OF THE LONG
TERM PERIOD.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
SOUTHWESTERLY WINDS WILL CONTINUE TO INCREASE IN STRENGTH THROUGH
THE MORNING HOURS...WITH OCCASIONAL GUSTS OF AROUND 20 KNOTS.
MOISTURE WILL GRADUALLY INCREASE AHEAD OF A COLD FRONT...WITH MVFR
CEILINGS BECOMING MORE COMMON BY EARLY AFTERNOON. DURING THE
EVENING...SOME AREAS OF LIGHT RAIN ARE EXPECTED TO DEVELOP. THIS
RAIN IS UNLIKELY TO HAVE A SIGNIFICANT ADDITIONAL IMPACT ON
AVIATION CONDITIONS...BUT CEILINGS WILL CONTINUE TO LOWER EVEN
OUTSIDE OF THE RAIN...WITH LOW-END MVFR (AND POSSIBLY IFR)
CONDITIONS EXPECTED FOR THE SECOND HALF OF THE FORECAST PERIOD.
RAIN IS EXPECTED TO COME TO AN END DURING THE OVERNIGHT
HOURS...ALTHOUGH THERE IS A CHANCE THAT SOME VERY LIGHT
RAIN/DRIZZLE/FLURRIES COULD CONTINUE INTO MONDAY MORNING. CEILINGS
MAY BEGIN TO GRADUALLY IMPROVE BEHIND THE COLD FRONT...BUT THIS
IMPROVEMENT WILL NOT BE QUICK. WINDS BEHIND THE FRONT WILL SHIFT
TO THE NORTH...WITH SUSTAINED VALUES OF 10-15 KNOTS EXPECTED.
OUTLOOK...MVFR CEILINGS WILL LIKELY CONTINUE THROUGH THE DAY ON
MONDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HICKMAN
NEAR TERM...HICKMAN
SHORT TERM...HICKMAN
LONG TERM...JGL
AVIATION...HATZOS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
424 AM EST SUN FEB 8 2015
.SYNOPSIS...
LOW PRESSURE WILL SLIDE SOUTHEAST ACROSS OHIO TODAY THEN PULL A COLD
FRONT SOUTH ACROSS THE AREA AS IT CONTINUES TO THE EAST COAST ON
MONDAY. HIGH PRESSURE WILL BUILD EAST ACROSS THE GREAT LAKES REGION
ON TUESDAY. A BROAD AREA OF LOW PRESSURE WILL MOVE OVER THE AREA ON
WEDNESDAY FOLLOWED BY AN ARCTIC COLD FRONT ON THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A BROAD AREA OF LOW PRESSURE IS IN PLACE NEAR CHICAGO THIS MORNING
WITH A STATIONARY FRONT EXTENDING EAST ACROSS LAKE ERIE. VERY WARM
AIR IS IN PLACE TO THE SOUTH WITH TEMPERATURES NEAR 50 DEGREES
ALREADY IN SOUTHERN INDIANA/OHIO. HAVE RAISED HIGHS SEVERAL DEGREES
FOR TODAY(MID 40S NORTH TO LOW 50S SOUTH) AS TEMPERATURES CONTINUE
TO WARM INTO EARLY AFTERNOON BEFORE CLOUDS THICKEN ENOUGH TO SLOW
THE WARMING. THE HRRR SHOWS THE STRATUS FINALLY FILLING IN EARLY
THIS AFTERNOON BUT WILL HAVE PLENTY OF HIGH CLOUD AROUND PRIOR TO
THAT. MODELS HAVE BEEN TOO MOIST OVER THE LAST DAY AND HAVE DELAYED
THE MENTION OF DRIZZLE OR LIGHT RAIN UNTIL MID AFTERNOON WHEN LOW
LEVEL ISENTROPIC ASCENT RAMPS UP IMMEDIATELY AHEAD OF THE
APPROACHING LOW.
SNOWPACK WILL GRADUALLY START TO MELT TODAY BUT NOT EXPECTING ENOUGH
WATER TO BE RELEASED TO CAUSE FLOODING PROBLEMS. THE GFS HAS REALLY
BEEN STRUGGLING WITH THE WARM AIR AND LOW LEVEL MOISTURE FOR TODAY
AND ALREADY HAS PRECIPITATION BLOSSOMING BY SUNRISE. WENT MORE WITH
A NAM/ECMWF BLEND FOR QPF WHICH HAS UP TO A TENTH OF AN INCH OF QPF
TODAY...WITH MOST AREAS SEEING LESS THAN A QUARTER INCH THROUGH
MONDAY MORNING...SLIGHTLY HIGHER IN NW PA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
AS THE UPPER LEVEL TROUGH DEEPENS OVERHEAD TONIGHT...THE LOW WILL
TRACK SOUTHEAST TOWARDS WEST VIRGINIA. AS THE LOW SLIDES TO THE
SOUTHEAST...COLDER AIR IN PLACE NORTH OF LAKE ERIE WILL BE PULLED
SOUTH OVER THE AREA. THIS DOES CREATE A CONCERN FOR PRECIP TYPE
TONIGHT...DESPITE THE WARM SURFACE TEMPERATURES TODAY. MODELS HAVE
BEEN SHOWING WINDS SWITCHING AROUND TO THE NE AS EARLY AS 21Z AT ERI
WITH TEMPERATURES FALLING TO NEAR OR BELOW FREEZING BY 01Z. A WARM
LAYER OF AIR WILL REMAIN ALOFT AS THE SURFACE STARTS TO COOL SO A
PERIOD OF FREEZING RAIN WILL BE POSSIBLE. THE AREA MOST LIKELY TO
EXPERIENCE FREEZING RAIN TONIGHT IS IN NE OH/NW PA BEFORE THE COLUMN
COOLS SUFFICIENTLY TO SWITCH OVER TO SNOW. ALTHOUGH FREEZING RAIN IS
IN THE FORECAST...IT WILL LIKELY BE LIGHT...WITH SOME UNCERTAINTY
STILL WITH SURFACE TEMPERATURES FOLLOWING THE WARM AFTERNOON. HAVE
DECIDED TO HOLD OFF ON ISSUING A FREEZING RAIN OR WINTER WEATHER
ADVISORY ALTHOUGH ONE MAY BE NEEDED TONIGHT. CONFIDENCE WAS NOT
THERE AT THIS TIME WHICH WILL ALLOW DAY SHIFT TO TAKE ANOTHER LOOK
AT THE WARM AIR IN THE COLUMN.
ALL SITES SHOULD BRIEFLY TRANSITION OVER TO SNOW AS THE COLD FRONT
IS PULLED SOUTH BUT ACCUMULATIONS WILL GENERALLY BE AN INCH OR LESS.
DID LEAVE A CHANCE OF SNOW SHOWERS IN THE FORECAST FOR MONDAY
ALTHOUGH DEEPER MOISTURE WILL QUICKLY PULL AWAY TO THE EAST. HIGHS
ON MONDAY WILL BE BACK IN THE MID 20S.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AFTER A BRIEF WARM UP ON WEDNESDAY MORE COLD WEATHER WILL MOVE BACK
IN FOR THE LATTER PART OF THE WEEK AND NEXT WEEKEND.
A RIDGE WILL MOVE ACROSS THE FORECAST AREA ON TUESDAY AND THEN A
FRONT WITH A LOW WILL MOVE THROUGH STARTING WEDNESDAY. THIS PART OF
THE EVENT LOOKS LIKE CHANCE POPS. SOME QUESTION ON THE PRECIPITATION
MAINLY SOUTH OF US 30...RAIN OR SNOW IS POSSIBLE. AS THE LOW SLIDES
SOUTHEAST INTO PENNSYLVANIA...COLDER AIR WILL START COMING IN FROM
THE NORTHWEST. THE WIND DIRECTION SHIFTS AROUND...MOISTURE IS
ADEQUATE...PLENTY OF COLD AIR AT 850 MB...-20C AND COLDER. WILL
MENTION A THREAT IN THE HAZARDOUS WEATHER OUTLOOK MAINLY FOR
ASHTABULA AND NW PA. HIGH PRESSURE WILL START BUILDING IN ON
FRIDAY...SOME SNOW SHOWERS COULD LINGER OVER NW PA EARLY FRIDAY.
ANOTHER FRONTAL SYSTEM WILL BE MOVING IN LATE FRIDAY NIGHT THROUGH
SATURDAY NIGHT WITH CHANCE POPS LOOKING REASONABLE AT THIS TIME.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS CONTINUE ACROSS THE AREA AT 05Z WITH MID AND HIGH
LEVEL MOISTURE IN PLACE. THE HRRR HAS BEEN VERIFYING WELL THROUGH
THE EVENING WITH CIGS DROPPING TO AROUND OVC040 AT KERI AND
REMAINING ABOVE OVC120 ELSEWHERE. WILL CONTINUE TO FOLLOW THROUGH
THE REMAINDER OF THE NIGHT WITH CIGS DROPPING INTO THE MVFR
CATEGORY LATE. LOW PRESSURE MOVES SLOWLY ACROSS THE AREA SUNDAY
ALONG A STATIONARY FRONT THAT WILL BE ACROSS OR JUST NORTH OF THE
AREA. EXPECT LOW MVFR AND IFR THROUGH THE DAY. MOST PRECIP SUNDAY
SHOULD BE LIGHT. PUT DRIZZLE IN TAFS. COLDER AIR MOVES IN BEHIND
THE LOW SUNDAY EVENING. FORECAST SOUNDINGS SUPPORT A PERIOD OF
FREEZING PRECIP BEFORE 00Z AT KERI AND THROUGH THE EVENING
ELSEWHERE.
.OUTLOOK...NON VFR SUNDAY NIGHT THROUGH MONDAY. NON VFR DEVELOPING
WEDNESDAY.
&&
.MARINE...
NO GALE FORCE WINDS ARE EXPECTED ON LAKE ERIE THROUGH THE FORECAST
PERIOD.
A FRONTAL SYSTEM WITH A LOW MOVING ALONG IT WILL BE THE WEATHER
MAKER ON LAKE ERIE FOR THE NEXT COUPLE OF DAYS. WINDS SHOULD REMAIN
BELOW 20 KNOTS. THEY SHOULD BE STRONGEST LATE SUNDAY NIGHT AS THE
LOW MOVES THROUGH PENNSYLVANIA. HIGH PRESSURE WILL THEN BUILD OVER
THE LAKE ON TUESDAY AND THEN ANOTHER DIFFUSE FRONTAL SYSTEM WILL
AFFECT THE LAKE WEDNESDAY AND WEDNESDAY NIGHT. AS THE LOW MOVES AWAY
WEDNESDAY NIGHT THE NORTH TO NORTHWEST FLOW WILL GET STRONGER BUT
REMAIN WELL BELOW GALE FORCE IN THE MODERATE TO STRONG COLD
ADVECTION. HIGH PRESSURE WILL BUILD IN BY FRIDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...KEC
SHORT TERM...KEC
LONG TERM...KIELTYKA
AVIATION...TK
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
414 AM EST SUN FEB 8 2015
.SYNOPSIS...
A LOW PRESSURE SYSTEM AND ASSOCIATED COLD FRONT WILL MOVE ACROSS
THE REGION TONIGHT INTO MONDAY MORNING. HIGH PRESSURE WILL THEN
SETTLE IN BEHIND THIS WEATHER SYSTEM MONDAY NIGHT INTO TUESDAY.
WARM TEMPERATURES TODAY WILL COOL BACK DOWN TO BELOW NORMAL READINGS
FOR THE FIRST PART OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A LOW PRESSURE SYSTEM NEAR NORTHERN ILLINOIS THIS MORNING WILL
MOVE EAST/SOUTHEAST TO OUR WESTERN FORECAST AREA BY THIS EVENING.
MODELS CONTINUE TO ADVECT LOW LEVEL MOISTURE AHEAD OF THIS LOW TOO
FAST INTO OUR AREA AND THIS RESULT IS HAVING CONSEQUENCES IN
TERMS OF FORECASTING HIGH TEMPERATURES AND CHANCES FOR PRECIPITATION.
THE RAP MODEL SEEMS TO HAVE THE BEST HANDLE ON THE INCREASING LOW
LEVEL MOISTURE FROM THE SOUTHWEST TODAY. AS A RESULT...HAVE
DELAYED ANY THREAT FOR LIGHT RAIN UNTIL LATE AFTERNOON. GIVEN A
WARM START THIS MORNING AND HOW WARM IT WAS YESTERDAY...HAVE TAKEN
A BLEND OF THE ECMWF AND RAP TO COME UP WITH TODAYS HIGHS.
ULTIMATELY...HOW WARM IT GETS WILL DEPEND ON THE SPEED AND
EXPANSION OF LOW LEVEL CLOUDS. WILL RANGE HIGHS FROM THE LOWER 50S
NORTH TO THE LOWER 60S ALONG AND SOUTH OF THE OHIO RIVER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
OPERATIONAL MODELS ARE IN PRETTY GOOD AGREEMENT IN TERMS OF
PLACEMENT AND TIMING OF SYNOPTIC SCALE SYSTEMS THROUGH THE SHORT
TERM PERIOD. HAVE USED A BLEND OF THE NAM/GFS/ECMWF.
FOR TONIGHT...AN UPR LVL S/WV WILL INTERACT WITH LIMITED DEEP
MOISTURE AND FRONTAL CONVERGENCE TO BRING THE THREAT FOR LIGHT RAIN
TO THE REGION THIS EVENING. HAVE CONTINUED WITH LIKELY POPS ALONG
AND SOUTHEAST OF THE LOW AND ITS ASSOCIATED FRONT. AS THE LOW AND
FRONT CONTINUE TO MOVE SOUTHEAST OVERNIGHT...COLDER AIR WILL
GRADUALLY FILTER BACK INTO THE AREA FROM THE NORTH. SOME OF THE
WRAP AROUND MOISTURE MAY MIX WITH OR CHANGE TO SNOW ACROSS THE
NORTHWEST HALF CWFA BEFORE TAPERING OFF. LITTLE TO NO SNOW
ACCUMULATION IS EXPECTED.
ON MONDAY...LOW AND FRONT WILL MOVE EAST ALONG WITH THE THREAT OF
PRECIPITATION. COULD BE SOME LINGERING LIGHT RAIN AND/OR SNOW
SHOWERS IN THE EAST DURING THE MORNING. MODELS INDICATE THAT
CONSIDERABLE LOW LEVEL MOISTURE/CLOUDS WILL REMAIN OVER THE AREA
AND WILL FORECAST CLOUDY SKIES. HIGHS WILL BE TRICKY GIVEN SHALLOW
CAA INTO THE REGION AND RELATIVELY WARM START IN THE SOUTHEAST.
THIS WILL RESULT IN A DOWNWARD TREND IN TEMPS ACRS THE SOUTHEAST
DURING THE MORNING BEFORE STEADYING OUT WHILE THE NORTHERN
LOCATIONS SEE JUST A SMALL INCREASE IN HIGHS GIVEN CAA AND CLOUDY
SKIES.
FOR MONDAY NIGHT INTO TUESDAY...HIGH PRESSURE WILL BUILD SOUTHEAST
INTO THE GREAT LAKES AND OHIO VALLEY. MODEL SOUNDINGS INDICATE
THAT CLOUDS WILL BE SLOW TO CLEAR FROM NORTHWEST TO SOUTHEAST...BUT
ALL AREAS SHOULD BECOME MOSTLY CLEAR/MOSTLY SUNNY BY TUESDAY AFTERNOON.
TEMPERATURES WILL DROP BACK DOWN TO BELOW NORMAL READINGS FOR
EARLY FEBRUARY.
HIGH PRESSURE WILL MOVE EAST TUESDAY NIGHT AS MID AND HIGH LEVEL
CLOUDS MOVE IN FROM THE WEST AHEAD OF THE NEXT WEATHER SYSTEM FOR
WEDNESDAY/THURSDAY TIME FRAME.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
MODELS ARE IN DECENT AGREEMENT WITH SHORT WAVE ENERGY PUSHING
ACROSS THE SOUTHERN GREAT LAKES DURING THE DAY ON WEDNESDAY. THE
BEST FORCING WITH THIS WILL REMAIN TO OUR NORTH...BUT WE COULD
STILL SEE SOME ISOLATED TO SCATTERED SHOWER ACTIVITY WORK IN
ACROSS OUR NORTHERN AREAS THROUGH THE DAY. WAA OUT AHEAD OF THIS
WILL HELP PUSH HIGHS UP INTO THE UPPER 30S NORTH TO LOWER/MID 40S
IN THE SOUTH. AS A RESULT...WOULD EXPECT ANY PCPN TO BE EITHER A
RAIN/SNOW MIX OR RAIN THROUGH WEDNESDAY AFTERNOON. AS THE SHORT
WAVE MOVES OFF TO THE EAST...AN ASSOCIATED ARCTIC COLD FRONT WILL
PUSH SOUTH ACROSS OUR AREA WEDNESDAY NIGHT WITH A MUCH COLDER
AIRMASS SETTLING IN THROUGH THE DAY ON THURSDAY. LOWS WEDNESDAY
NIGHT WILL FALL INTO THE TEENS TO LOW/MID 20S...WITH LITTLE IN THE
WAY OF RECOVERY THROUGH THE DAY ON THURSDAY. AS WE GET INTO SOME
CYCLONIC LOW LEVEL FLOW AND DEVELOP A FETCH OFF OF LAKE
MICHIGAN...EXPECT TO SEE SOME ISOLATED TO SCATTERED SNOW SHOWER
ACTIVITY LATER WEDNESDAY NIGHT AND INTO THURSDAY.
DRY BUT CONTINUED COLD CONDITIONS ARE EXPECTED FOR FRIDAY AS HIGH
PRESSURE BUILDS BACK INTO THE AREA. HIGHS ON FRIDAY WILL GENERALLY
BE IN THE 20S. IT LOOKS LIKE A WEAK CLIPPER TYPE SYSTEM MAY DROP
DOWN TOWARD THE AREA NEXT WEEKEND. HOWEVER...TIMING AND PLACEMENT
HAVE VARIED OVER THE LAST COUPLE OF RUNS OF THE GFS AND ECMWF SO
WILL LIMIT POPS TO 20 PERCENT OR LESS THROUGH THE END OF THE LONG
TERM PERIOD.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
SOUTHWESTERLY WINDS WILL CONTINUE THROUGH MOST OF THE TAF
PERIOD...IN ADVANCE OF A COLD FRONT THAT IS FORECAST TO MOVE
THROUGH ON SUNDAY NIGHT. MOISTURE WILL GRADUALLY INCREASE AHEAD OF
THIS FRONT...WITH MVFR CEILINGS BECOMING MORE COMMON BY EARLY
AFTERNOON...AND CHANCES FOR LIGHT RAIN BY LATE AFTERNOON. WINDS
MAY GUST TO AROUND 20 KNOTS.
AFTER THE COLD FRONT MOVES THROUGH...WINDS WILL SHIFT TO THE NNW.
LIGHT RAIN OR DRIZZLE MAY CONTINUE INTO SUNDAY NIGHT AND EARLY
MONDAY MORNING.
OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES ARE POSSIBLE MONDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HICKMAN
NEAR TERM...HICKMAN
SHORT TERM...HICKMAN
LONG TERM...JGL
AVIATION...HATZOS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1141 PM EST SAT FEB 7 2015
.SYNOPSIS...
A STATIONARY FRONT WILL SET UP JUST NORTH OF THE AREA AND MOVE
LITTLE THROUGH SUNDAY. LOW PRESSURE IS EXPECTED TO MOVE EAST
ALONG THE FRONT ON SUNDAY AFTERNOON...WHICH WILL PULL THE FRONT
SOUTHWARD AND ALLOW THE RETURN OF COLDER TEMPERATURES. HIGH
PRESSURE WILL BUILD ACROSS THE AREA TUESDAY AND THE NEXT SYSTEM
IS EXPECTED WEDNESDAY INTO THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
LARGELY UNEVENTFUL TONIGHT AS WE REMAIN ON THE WARM SIDE OF A NEARLY
STATIONARY FRONT. DEWPOINTS SLOWLY RISING SO DEVELOPMENT OF LOWER
CLOUDS AND POSSIBLE FOG AND DRIZZLE WILL LIKELY BE DELAYED AND MAY
NOT EVEN OCCUR BY DAYBREAK FOR MUCH OF THE AREA. TEMPS HOLDING
STEADY...KEEPING SPREADS AROUND 10 DEGREES MOST PLACES. TEMPS MAY
FALL A DEGREE OR TWO BUT THAT`S ABOUT IT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY NIGHT/...
THE ARRIVAL OF THE LOW SUNDAY WILL BRING MORE WIDESPREAD
PRECIPITATION TO THE AREA. TEMPERATURES WILL BE HOLDING STEADY
NEAR 40/LOWER 40S. RAINFALL IS STILL EXPECTED TO BE A QUARTER TO
HALF OF AN INCH. THE TEMPS/TD AND RAINFALL WILL NOT BE ENOUGH TO
CAUSE ANYTHING MORE THAN NUISANCE WATER ISSUES. LIMITED RELEASE OF
ANY SNOWPACK WATER. SUNDAY AFTERNOON THE BAROCLINIC ZONE WILL BE
SHIFTING SOUTHWARD AND THE COLD AIR WILL REACH ERIE PA FIRST. AS
THE COLD AIR PRESSES SOUTHWARD THERE IS A CHANCE OF A PERIOD OF
FREEZING RAIN BETWEEN THE TRANSITION FROM RAIN TO SNOW. COLD AIR
AT THE SURFACE MAY ARRIVE BEFORE IT DOES ALOFT. CONFIDENCE AND
IMPACT NOT HIGH ENOUGH FOR ANY HEADLINES AT THIS POINT. SNOW
CHANCES CONTINUE INTO MONDAY BEFORE ONLY A FEW FLURRIES ARE LEFT
BY EVENING. LESS THAN AN INCH OR TWO EXPECTED MOST PLACES...WITH
MAYBE 3 OR 4 INCHES FOR NW PA.
TEMPERATURES WILL REMAIN NEARLY STEADY MONDAY IN THE 20S. HAVE
KEPT THE CLOUDS AROUND LONGER MONDAY NIGHT WITH MOISTURE LIKELY
GETTING TRAPPED UNDER THE INVERSION. THIS WILL HAVE AN IMPACT ON
TEMPERATURES. WITH THE CLOUD COVER HAVE KEPT TEMPERATURES IN
DOUBLE DIGITS. ANY CLEARING COULD ALLOW FOR SINGLE DIGITS. HIGH
PRESSURE FOR TUESDAY.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ANOTHER CLIPPER STORM SYSTEM WILL MOVE ACROSS THE GREAT LAKES REGION
WEDNESDAY INTO WEDNESDAY NIGHT. THE MAIN SWATH OF SNOW WITH IT LOOKS
AS IF IT WILL REMAIN OVER SOUTHERN CANADA INTO NY STATE. HOWEVER A
STRONG AREA OF HIGH PRESSURE WILL ARRIVE IN THE WAKE OF THE CLIPPER.
NORTHERLY WINDS CROSSING THE LAKE WILL AT LEAST PRODUCE SOME LAKE
EFFECT SNOW SHOWERS. WE WILL NEED TO MONITOR THIS CLOSELY NEXT WEEK
AND WATCH FOR ANY SIGNIFICANT OPENINGS IN THE ICE COVER ON THE LAKE.
IF A LARGE ENOUGH CRACK OPENS UP WE COULD SEE A MORE MEANINGFUL
ACCUMULATION. HIGH PRESSURE SHOULD BE IN CONTROL OF THE REGION FOR
FRIDAY.
WEDNESDAY APPEARS TO BE THE WARMEST DAY OF THE LONG TERM FORECAST
WITH HIGHS INTO THE 30S. COOLER THURSDAY INTO FRIDAY WITH HIGHS IN
THE TEENS TO MAYBE LOWER 20S. VERY COLD TEMPERATURES POSSIBLE IF
SKIES CLEAR THURSDAY NIGHT/FRIDAY MORNING WITH LOWS POTENTIALLY
DIPPING BELOW ZERO.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS CONTINUE ACROSS THE AREA AT 05Z WITH MID AND HIGH
LEVEL MOISTURE IN PLACE. THE HRRR HAS BEEN VERIFYING WELL THROUGH
THE EVENING WITH CIGS DROPPING TO AROUND OVC040 AT KERI AND
REMAINING ABOVE OVC120 ELSEWHERE. WILL CONTINUE TO FOLLOW THROUGH
THE REMAINDER OF THE NIGHT WITH CIGS DROPPING INTO THE MVFR
CATEGORY LATE. LOW PRESSURE MOVES SLOWLY ACROSS THE AREA SUNDAY
ALONG A STATIONARY FRONT THAT WILL BE ACROSS OR JUST NORTH OF THE
AREA. EXPECT LOW MVFR AND IFR THROUGH THE DAY. MOST PRECIP SUNDAY
SHOULD BE LIGHT. PUT DRIZZLE IN TAFS. COLDER AIR MOVES IN BEHIND
THE LOW SUNDAY EVENING. FORECAST SOUNDINGS SUPPORT A PERIOD OF
FREEZING PRECIP BEFORE 00Z AT KERI AND THROUGH THE EVENING
ELSEWHERE.
.OUTLOOK...NON VFR SUNDAY NIGHT THROUGH MONDAY. NON VFR DEVELOPING
WEDNESDAY.
&&
.MARINE...
NO GALE FORCE WINDS ARE EXPECTED ON LAKE ERIE THROUGH THE FORECAST
PERIOD.
A COLD FRONT OVER THE NORTHERN LAKES WILL SAG SOUTHWARD ACROSS THE
CENTRAL LAKES TONIGHT. THE FRONT WILL LIKELY DROP SOUTH ACROSS LAKE
ERIE LATE SUNDAY. THIS SHOULD PRODUCE SOUTHWESTERLY WINDS ACROSS
LAKE ERIE INTO SUNDAY. LOW PRESSURE WILL DEVELOP ON THE FRONT SUNDAY
NIGHT AND TRACK ACROSS OHIO. WINDS WILL INCREASE FROM A NORTHERLY
DIRECTION IN THE WAKE OF THE LOW BUT SHOULD REMAIN UNDER 20 KNOTS.
THE LOW WILL MOVE OFF THE EAST COAST ON MONDAY. HIGH PRESSURE WILL
SLIDE ACROSS EASTERN CANADA EARLY NEXT WEEK. ANOTHER COLD FRONT WILL
MOVE ACROSS LAKE ERIE LATE WEDNESDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...OUDEMAN
NEAR TERM...OUDEMAN
SHORT TERM...OUDEMAN
LONG TERM...MULLEN
AVIATION...TK
MARINE...MULLEN
AREA FORECAST DISCUSSION
NWS NORMAN OK
944 PM CST MON FEB 9 2015
.DISCUSSION...
ONLY MINOR UPDATES TO THE PACKAGE THIS EVENING. AN AREA OF
RESTRICTED VISIBILITY HAS DEVELOPED IN NORTHERN OKLAHOMA AND
PORTIONS OF KANSAS INCLUDING KPNC. ALTHOUGH RAP AND HRRR SUGGEST
THAT ANY AREAS OF SIGNIFICANT FOG WILL REMAIN NORTH OF OKLAHOMA...
HAVE ADDED THE MENTION OF PATCHY FOG IN NORTH CENTRAL OKLAHOMA
GIVEN THE CURRENT REDUCTION OF VISIBILITY. HAVE ALSO REDUCED THE
FORECAST CLOUD COVER IN NORTHWEST OKLAHOMA LATER TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 539 PM CST MON FEB 9 2015/
AVIATION...
00Z TAFS...VFR CONDITIONS WILL PERSIST THROUGH AROUND 09Z.
THEREAFTER...SOME PATCHY FOG MAY REDUCE VSBYS TO 2 TO 5 SM FROM
CENTRAL THROUGH NORTHERN AND WESTERN OKLAHOMA. IFR CIGS MAY ALSO
OCCUR BRIEFLY AT KCSM/KGAG EARLY TUESDAY. WINDS WILL GRADUALLY
SHIFT FROM EAST TO SOUTHEAST THROUGH THE NIGHT...BECOMING GUSTY
EARLY TUESDAY. A WEAK FRONT WILL RESULT IN AT NORTHERLY WIND SHIFT
BY 18Z AT KGAG AND KWWR. VFR CONDITIONS SHOULD RETURN EARLY
THURSDAY TO ANY TERMINALS THAT SEE PATCHY FOG.
PREV DISCUSSION... /ISSUED 344 PM CST MON FEB 9 2015/
DISCUSSION...
VERY MILD WEATHER WILL CONTINUE ONE MORE DAY...BEFORE A STRONG
COLD FRONT SENDS TEMPERATURES TUMBLING BACK DOWN TOWARD THE
SEASONAL AVERAGE. MOISTURE WILL BE MEAGER WITH THE FRONT...SO RAIN
CHANCES WILL BE LOW.
THE TEMPERATURE ROLLER COASTER WILL CONTINUE WITH A WARMING TREND
THURSDAY AND FRIDAY...FOLLOWED BY ANOTHER STRONG COLD FRONT ON
SATURDAY. THEN...ANOTHER WARMING TREND...AND ANOTHER COLD FRONT
EARLY NEXT WEEK...JUST BEYOND THE REACH OF THIS FORECAST. EACH
COLD FRONT WILL BRING A COLDER AIRMASS THAN THE ONE BEFORE. NONE
OF THEM ARE LIKELY TO INVOLVE ENOUGH MOISTURE FOR SIGNIFICANT
PRECIPITATION.
WINDS BEHIND EACH COLD FRONT WILL BE FAIRLY STRONG AND GUSTY.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 41 69 43 55 / 0 0 0 10
HOBART OK 44 72 43 57 / 0 0 0 0
WICHITA FALLS TX 45 76 46 62 / 0 0 0 0
GAGE OK 41 68 37 53 / 0 0 0 10
PONCA CITY OK 35 63 39 50 / 0 0 0 10
DURANT OK 42 67 45 63 / 0 0 0 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS TULSA OK
853 PM CST MON FEB 9 2015
.DISCUSSION...
ANOTHER QUIET EVENING ACROSS THE FORECAST AREA. DECK OF LOW CLOUDS
THAT BACK-DOORED INTO OUR AREA THIS MORNING HAD RETREATED DURING
THE DAYTIME HOURS...BUT HAS SINCE SAGGED BACK TO THE SOUTHWEST
AGAIN. THE LATEST HRRR SHOWS SOME PENETRATION INTO FAR NE OK AND
NW AR...BUT ONLY TEMPORARILY. WE SHALL SEE. IT IS OFTEN DIFFICULT
FOR A CLOUD DECK TO BREAK UP AT NIGHT. I ALSO ADDED SOME FOG/CLOUD
COVER WESTWARD ALONG THE KS BORDER BASED ON PERSISTENT HRRR
FORECAST. SKY GRIDS MAY NEED CONTINUAL TWEAKING BASED ON WHAT THE
EXTENSIVE LOW CLOUD DECK TO OUR NORTHEAST DOES.
LACY
&&
.PREV DISCUSSION... /ISSUED 530 PM CST MON FEB 9 2015/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
FOR THE MOST PART VFR CONDITIONS WILL PREVAIL THROUGH THE
PERIOD. POSSIBLE EXCEPTIONS WILL BE THAT PARTS OF NW ARKANSAS AND
FAR NORTHERN OK COULD SEE PATCHY FOG LATER TONIGHT....AND AREA OF
LOW CLOUDS MAY SPREAD BACK WEST NEAR KS/MO BORDERS OVERNIGHT AS
LOW LEVEL WINDS SWITCH AROUND TO THE EAST THEN SOUTHEAST. BOTH
SCENARIOS BRING RISK OF MVFR CONDITIONS BETWEEN APPROX 06-15Z.
PREV DISCUSSION... /ISSUED 328 PM CST MON FEB 9 2015/
DISCUSSION...
SFC RIDGE AXIS OVERHEAD TODAY WITH GOOD EAST/WEST GRADIENT IN
AFTERNOON TEMPS. RIDGE TO SHIFT EASTWARD ON TUESDAY ALLOWING
WARMER TEMPS AND RETURN TO SOUTHERLY WINDS. PATCHY FOG MAY DEVELOP
TONIGHT BEFORE WINDS PICK UP OTHERWISE CLEAR SKIES WILL PREVAIL.
COLD FRONT TO PUSH THROUGH THE AREA ON WEDNESDAY WITH A SLIGHT
CHANCE OF SHOWERS FOR SE OK / WESTERN AR...WITH NOTICEABLY COOLER
TEMPS EXPECTED ON THURSDAY. A BRIEF WARM UP IS LIKELY ON FRIDAY
BEFORE AN EVEN STRONGER COLD FRONT SWEEPS THROUGH THE AREA PUSHING
TEMPS BELOW NORMAL FOR THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 35 69 40 57 / 0 0 0 0
FSM 36 64 38 59 / 0 0 0 20
MLC 37 69 43 59 / 0 0 0 20
BVO 29 69 32 54 / 0 0 0 0
FYV 28 62 36 56 / 0 0 0 10
BYV 28 61 36 56 / 0 0 0 10
MKO 35 66 38 58 / 0 0 0 10
MIO 30 64 36 52 / 0 0 0 0
F10 37 68 42 57 / 0 0 0 20
HHW 39 66 41 65 / 0 0 0 20
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...30
AREA FORECAST DISCUSSION
NWS TULSA OK
1135 AM CST SUN FEB 8 2015
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
VFR EASTERN OK TAF SITES KTUL/KRVS/KBVO/KMLC THROUGH PERIOD.
NORTHWEST TAF SITES /KXNA/KFYV/KROG/KFSM RISK MVFR CIGS 10Z-15Z
OTHERWISE VFR.
&&
.PREV DISCUSSION... /ISSUED 1057 AM CST SUN FEB 8 2015/
DISCUSSION...
WEAK FRONT MOVING ALONG AS PREVIOSLY SCHEDULED.
MINOR TWEAK TO GRIDS FOR MORNING UPDATE. GW
PREV DISCUSSION... /ISSUED 551 AM CST SUN FEB 8 2015/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
LOWER CEILINGS EXPECTED TO SPREAD NORTH INTO SOUTHEAST OKLAHOMA AND
NORTHWEST ARKANSAS THIS MORNING WITH A BRIEF PERIOD OF MVFR
CONDITIONS. LOW CLOUDS WILL LIKELY BEGIN TO SHIFT EAST OF THE AREA
EARLY THIS AFTERNOON AS FRONTAL BOUNDARY PUSHES INTO SE OK/NW AR.
PREV DISCUSSION... /ISSUED 306 AM CST SUN FEB 8 2015/
DISCUSSION...
COLD FRONT APPROACHING FROM THE NORTHWEST IS ONLY A COUPLE OF
COUNTIES AWAY FROM THE NORTHWEST EDGE OF THE FORECAST AREA...AND
WILL BEGIN TO ENTER AREAS NORTH AND WEST OF TULSA SHORTLY AFTER
SUNRISE. THE MAIN EFFECT IMMEDIATELY BEHIND THE FRONT WILL BE A
DROP IN DEW POINT...SOMETHING THAT SHOULD HELP TEMPERATURES WARM
RATHER QUICKLY TODAY...LIKELY TO WARMER LEVELS THAN THE LAST COUPLE
OF DAYS DESPITE BEING POST FRONTAL. THE LATEST HRRR FORECAST HIGH
TEMPERATURES TODAY ARE VERY SIMILAR TO WHAT MIXING THE GFS 875 MB
/A LEVEL SUPPORTED BY RUC FORECAST SOUNDINGS AS WELL AS THE GFS/
TEMPERATURES TO THE SURFACE WOULD SUPPORT. DESPITE THIS...AM A
BIT HESITANT TO GO STRAIGHT WITH THE HRRR FORECAST GIVEN THE LAST
COUPLE OF DAYS HAVE NOT LIVED UP TO EXPECTATIONS...BUT WILL STILL
GO A COUPLE OF DEGREES HIGHER THAN OTHER GUIDANCE VALUES. THE
WARMER/DRIER CONDITIONS BEHIND THE FRONT...IN ADDITION TO
INCREASING NORTHWESTERLY WINDS...WILL INCREASE THE FIRE DANGER BY
THIS AFTERNOON...ESPECIALLY ACROSS NORTHEAST OKLAHOMA.
THE POST FRONTAL LOWER MOISTURE WILL ALSO HELP TO SCOUR OUT LOW
CLOUDS THAT SHOULD DEVELOP ACROSS PORTIONS OF SOUTHEAST OKLAHOMA
AND WESTERN ARKANSAS THROUGH THE MORNING HOURS. THE CLOUDS HAVE
BEEN A BIT SLOW TO DEVELOP COMPARED TO EARLIER EXPECTATIONS...BUT
SATELLITE TRENDS HAVE SHOWN A QUICK NORTHWARD EXPANSION ACROSS
EAST TEXAS WITHIN THE LAST COUPLE OF HOURS. THIS INCREASE IN AREAL
COVERAGE SHOULD CONTINUE INTO THE SOUTHEASTERN HALF OF THE
FORECAST AREA THROUGH THE EARLY TO MID MORNING HOURS.
COOLER...BUT STILL ABOVE NORMAL...TEMPERATURES WILL ARRIVE FOR
MONDAY...WITH SLIGHTLY WARMER CONDITIONS FOR TUESDAY AS SOUTHERLY
WINDS MAKE A RETURN. THE NEXT...AND MUCH STRONGER...COLD FRONT
WILL ARRIVE WEDNESDAY. OVERALL RAIN POTENTIAL WITH THE FRONT
STILL LOOKS QUESTIONABLE...AND MOST SPOTS SHOULD REMAIN DRY. WILL
CONTINUE WITH THE SLIGHT CHANCE POPS DURING THE
WEDNESDAY/WEDNESDAY NIGHT PERIOD. TEMPERATURES FINALLY RETURN TO
NEAR AND TO BELOW NORMAL THURSDAY BEHIND THE FRONT...WITH SOME
MODERATION FRIDAY AND INTO THE WEEKEND. PREDOMINANT NORTHWEST FLOW
ALOFT SHOULD KEEP THIS WARMUP FROM GETTING TOO OUT OF HAND.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 41 64 39 70 / 0 0 0 0
FSM 42 67 39 65 / 0 0 0 0
MLC 43 68 40 68 / 0 0 0 0
BVO 34 62 33 69 / 0 0 0 0
FYV 37 59 31 62 / 0 0 0 0
BYV 39 57 33 60 / 0 0 0 0
MKO 40 64 38 67 / 0 0 0 0
MIO 37 58 34 65 / 0 0 0 0
F10 42 66 40 69 / 0 0 0 0
HHW 42 71 41 68 / 0 0 0 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...21
LONG TERM....07
AVIATION...21
AREA FORECAST DISCUSSION
NWS TULSA OK
1057 AM CST SUN FEB 8 2015
.DISCUSSION...
WEAK FRONT MOVING ALONG AS PREVIOSLY SCHEDULED.
MINOR TWEAK TO GRIDS FOR MORNING UPDATE. GW
&&
.PREV DISCUSSION... /ISSUED 551 AM CST SUN FEB 8 2015/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
LOWER CEILINGS EXPECTED TO SPREAD NORTH INTO SOUTHEAST OKLAHOMA AND
NORTHWEST ARKANSAS THIS MORNING WITH A BRIEF PERIOD OF MVFR
CONDITIONS. LOW CLOUDS WILL LIKELY BEGIN TO SHIFT EAST OF THE AREA
EARLY THIS AFTERNOON AS FRONTAL BOUNDARY PUSHES INTO SE OK/NW AR.
PREV DISCUSSION... /ISSUED 306 AM CST SUN FEB 8 2015/
DISCUSSION...
COLD FRONT APPROACHING FROM THE NORTHWEST IS ONLY A COUPLE OF
COUNTIES AWAY FROM THE NORTHWEST EDGE OF THE FORECAST AREA...AND
WILL BEGIN TO ENTER AREAS NORTH AND WEST OF TULSA SHORTLY AFTER
SUNRISE. THE MAIN EFFECT IMMEDIATELY BEHIND THE FRONT WILL BE A
DROP IN DEW POINT...SOMETHING THAT SHOULD HELP TEMPERATURES WARM
RATHER QUICKLY TODAY...LIKELY TO WARMER LEVELS THAN THE LAST COUPLE
OF DAYS DESPITE BEING POST FRONTAL. THE LATEST HRRR FORECAST HIGH
TEMPERATURES TODAY ARE VERY SIMILAR TO WHAT MIXING THE GFS 875 MB
/A LEVEL SUPPORTED BY RUC FORECAST SOUNDINGS AS WELL AS THE GFS/
TEMPERATURES TO THE SURFACE WOULD SUPPORT. DESPITE THIS...AM A
BIT HESITANT TO GO STRAIGHT WITH THE HRRR FORECAST GIVEN THE LAST
COUPLE OF DAYS HAVE NOT LIVED UP TO EXPECTATIONS...BUT WILL STILL
GO A COUPLE OF DEGREES HIGHER THAN OTHER GUIDANCE VALUES. THE
WARMER/DRIER CONDITIONS BEHIND THE FRONT...IN ADDITION TO
INCREASING NORTHWESTERLY WINDS...WILL INCREASE THE FIRE DANGER BY
THIS AFTERNOON...ESPECIALLY ACROSS NORTHEAST OKLAHOMA.
THE POST FRONTAL LOWER MOISTURE WILL ALSO HELP TO SCOUR OUT LOW
CLOUDS THAT SHOULD DEVELOP ACROSS PORTIONS OF SOUTHEAST OKLAHOMA
AND WESTERN ARKANSAS THROUGH THE MORNING HOURS. THE CLOUDS HAVE
BEEN A BIT SLOW TO DEVELOP COMPARED TO EARLIER EXPECTATIONS...BUT
SATELLITE TRENDS HAVE SHOWN A QUICK NORTHWARD EXPANSION ACROSS
EAST TEXAS WITHIN THE LAST COUPLE OF HOURS. THIS INCREASE IN AREAL
COVERAGE SHOULD CONTINUE INTO THE SOUTHEASTERN HALF OF THE
FORECAST AREA THROUGH THE EARLY TO MID MORNING HOURS.
COOLER...BUT STILL ABOVE NORMAL...TEMPERATURES WILL ARRIVE FOR
MONDAY...WITH SLIGHTLY WARMER CONDITIONS FOR TUESDAY AS SOUTHERLY
WINDS MAKE A RETURN. THE NEXT...AND MUCH STRONGER...COLD FRONT
WILL ARRIVE WEDNESDAY. OVERALL RAIN POTENTIAL WITH THE FRONT
STILL LOOKS QUESTIONABLE...AND MOST SPOTS SHOULD REMAIN DRY. WILL
CONTINUE WITH THE SLIGHT CHANCE POPS DURING THE
WEDNESDAY/WEDNESDAY NIGHT PERIOD. TEMPERATURES FINALLY RETURN TO
NEAR AND TO BELOW NORMAL THURSDAY BEHIND THE FRONT...WITH SOME
MODERATION FRIDAY AND INTO THE WEEKEND. PREDOMINANT NORTHWEST FLOW
ALOFT SHOULD KEEP THIS WARMUP FROM GETTING TOO OUT OF HAND.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 74 41 64 39 / 0 0 0 0
FSM 72 42 67 39 / 10 0 0 0
MLC 72 43 68 40 / 10 0 0 0
BVO 72 34 62 33 / 0 0 0 0
FYV 69 37 59 31 / 0 0 0 0
BYV 70 39 57 33 / 0 0 0 0
MKO 71 40 64 38 / 0 0 0 0
MIO 69 37 58 34 / 0 0 0 0
F10 72 42 66 40 / 0 0 0 0
HHW 68 42 71 41 / 10 0 0 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...21
LONG TERM....08
AREA FORECAST DISCUSSION
NWS TULSA OK
306 AM CST SUN FEB 8 2015
.DISCUSSION...
COLD FRONT APPROACHING FROM THE NORTHWEST IS ONLY A COUPLE OF
COUNTIES AWAY FROM THE NORTHWEST EDGE OF THE FORECAST AREA...AND
WILL BEGIN TO ENTER AREAS NORTH AND WEST OF TULSA SHORTLY AFTER
SUNRISE. THE MAIN EFFECT IMMEDIATELY BEHIND THE FRONT WILL BE A
DROP IN DEW POINT...SOMETHING THAT SHOULD HELP TEMPERATURES WARM
RATHER QUICKLY TODAY...LIKELY TO WARMER LEVELS THAN THE LAST COUPLE
OF DAYS DESPITE BEING POST FRONTAL. THE LATEST HRRR FORECAST HIGH
TEMPERATURES TODAY ARE VERY SIMILAR TO WHAT MIXING THE GFS 875 MB
/A LEVEL SUPPORTED BY RUC FORECAST SOUNDINGS AS WELL AS THE GFS/
TEMPERATURES TO THE SURFACE WOULD SUPPORT. DESPITE THIS...AM A
BIT HESITANT TO GO STRAIGHT WITH THE HRRR FORECAST GIVEN THE LAST
COUPLE OF DAYS HAVE NOT LIVED UP TO EXPECTATIONS...BUT WILL STILL
GO A COUPLE OF DEGREES HIGHER THAN OTHER GUIDANCE VALUES. THE
WARMER/DRIER CONDITIONS BEHIND THE FRONT...IN ADDITION TO
INCREASING NORTHWESTERLY WINDS...WILL INCREASE THE FIRE DANGER BY
THIS AFTERNOON...ESPECIALLY ACROSS NORTHEAST OKLAHOMA.
THE POST FRONTAL LOWER MOISTURE WILL ALSO HELP TO SCOUR OUT LOW
CLOUDS THAT SHOULD DEVELOP ACROSS PORTIONS OF SOUTHEAST OKLAHOMA
AND WESTERN ARKANSAS THROUGH THE MORNING HOURS. THE CLOUDS HAVE
BEEN A BIT SLOW TO DEVELOP COMPARED TO EARLIER EXPECTATIONS...BUT
SATELLITE TRENDS HAVE SHOWN A QUICK NORTHWARD EXPANSION ACROSS
EAST TEXAS WITHIN THE LAST COUPLE OF HOURS. THIS INCREASE IN AREAL
COVERAGE SHOULD CONTINUE INTO THE SOUTHEASTERN HALF OF THE
FORECAST AREA THROUGH THE EARLY TO MID MORNING HOURS.
COOLER...BUT STILL ABOVE NORMAL...TEMPERATURES WILL ARRIVE FOR
MONDAY...WITH SLIGHTLY WARMER CONDITIONS FOR TUESDAY AS SOUTHERLY
WINDS MAKE A RETURN. THE NEXT...AND MUCH STRONGER...COLD FRONT
WILL ARRIVE WEDNESDAY. OVERALL RAIN POTENTIAL WITH THE FRONT
STILL LOOKS QUESTIONABLE...AND MOST SPOTS SHOULD REMAIN DRY. WILL
CONTINUE WITH THE SLIGHT CHANCE POPS DURING THE
WEDNESDAY/WEDNESDAY NIGHT PERIOD. TEMPERATURES FINALLY RETURN TO
NEAR AND TO BELOW NORMAL THURSDAY BEHIND THE FRONT...WITH SOME
MODERATION FRIDAY AND INTO THE WEEKEND. PREDOMINANT NORTHWEST FLOW
ALOFT SHOULD KEEP THIS WARMUP FROM GETTING TOO OUT OF HAND.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 76 41 64 39 / 0 0 0 0
FSM 73 42 67 39 / 10 0 0 0
MLC 73 43 68 40 / 10 0 0 0
BVO 74 34 62 33 / 0 0 0 0
FYV 70 37 59 31 / 0 0 0 0
BYV 71 39 57 33 / 0 0 0 0
MKO 73 40 64 38 / 0 0 0 0
MIO 70 37 58 34 / 0 0 0 0
F10 74 42 66 40 / 0 0 0 0
HHW 69 42 71 41 / 10 0 0 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...12
LONG TERM....22
AREA FORECAST DISCUSSION
NWS TULSA OK
1126 PM CST SAT FEB 7 2015
.DISCUSSION...
THE 06Z TAF DISCUSSION IS INCLUDED BELOW...
&&
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
CONFLICTING SIGNALS IN THE DATA HAVE LOWERED MY CONFIDENCE
REGARDING THE CIG/VSBY FORECAST FOR THE OVERNIGHT. THE STATISTICAL
GUIDANCE IS QUITE PESSIMISTIC...DEVELOPING IFR CIGS/VSBYS AT MANY
SITES...WHILE TIME/HEIGHT PLOT DATA FROM THE RUC/RAP AND TO SOME
EXTENT THE HRRR SHOWS SOME POTENTIAL FOR FOG RATHER THAN STRATUS.
THE HRRR IS PESSIMISTIC ON THE DVLPMT OF WIDESPREAD LOW
CIGS...KEEPING THIS MAINLY SOUTH OF THE OUACHITAS. I HEDGED THE
FORECAST WITH TEMPOS TO COVER THE POSSIBILITIES. VFR CONDITIONS
ARE LIKELY AT ALL LOCATIONS BY MIDDAY SUNDAY.
LACY
&&
.PREV DISCUSSION... /ISSUED 923 PM CST SAT FEB 7 2015/
..UPDATE...
DISCUSSION...
SUSTAINED SOUTHERLY WINDS AND INCREASING LOW LEVEL CLOUD COVER
OVER FAR SE OK / WESTERN AR WILL ALL LEAD TO A RELATIVELY MILD
NIGHT. FORECAST LOWS LOOK ON TRACK AND UPDATE WILL ADJUST FOR
OBSERVED TRENDS AND LATEST HOURLY GUIDANCE.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 45 72 41 64 / 0 0 0 0
FSM 46 72 42 67 / 10 10 0 0
MLC 50 71 43 68 / 10 10 0 0
BVO 42 73 34 62 / 0 0 0 0
FYV 47 68 37 59 / 10 0 0 0
BYV 47 68 39 57 / 10 0 0 0
MKO 46 71 40 64 / 0 0 0 0
MIO 46 70 37 58 / 0 0 0 0
F10 48 72 42 66 / 10 0 0 0
HHW 49 69 42 71 / 10 10 0 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...30
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
604 PM EST SUN FEB 8 2015
.SYNOPSIS...
LOW PRESSURE WILL TRACK THROUGH THE OHIO VALLEY INTO THE MID
ATLANTIC STATES TONIGHT THROUGH MONDAY...SPREADING MIXED
PRECIPITATION ACROSS CENTRAL PENNSYLVANIA. COLDER AIR WILL RETURN
FOR MIDWEEK BEFORE ANOTHER FRONTAL SYSTEM APPROACHES FOR THURSDAY
AND FRIDAY. BITTERLY COLD AIR WILL FOLLOW FOR THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL MIDNIGHT TONIGHT/...
LATEST HRRR INDICATES THE CAD PATTERN WILL REMAIN ENTRENCHED FROM
THE POCONOS INTO SERN PA AS COLD AIR FILTERS IN FROM THE NORTHEAST.
RADAR RETURNS HAVE INCREASED THIS AFTERNOON OVER THIS AREA WHICH
IS A GOOD INDICATION OF THE SHALLOW LOW LEVEL COLD AIR UNDERCUTTING
THE MORE ROBUST WAA ALOFT. VIRGA HAS BEEN REPORTED AT MDT WITH
DEWPOINT DEPRESSIONS STILL RUNNING ABOUT 10 DEGREES.
IN CONTRAST TO THE CAD IN LWR SUSQ VLY...MILD SW FLOW ACROSS THE
ALLEGHENIES HAS PUSHED TEMPS INTO THE 40S AND LOW 50S. THE STRONG
FRONTAL ZONE IS STILL NORTH OF THE NY BORDER...STRETCHING NE FROM
JUST SOUTH OF ERIE BETWEEN JHW/OLE.
ANY PRECIP THAT FALLS IN THE NORTHERN TIER EARLY TONIGHT SHOULD
BE MAINLY RAIN ALTHOUGH WILL NEED TO WATCH THE ENDLESS MTNS AND
SRN POCONO REGIONS...WHERE TEMPS WILL COOLING DOWN CLOSER TO
FREEZING.
&&
.SHORT TERM /MIDNIGHT TONIGHT THROUGH MONDAY NIGHT/...
*COMPLEX WINTER WEATHER SYSTEM TO IMPACT THE AREA LATE TONIGHT
THROUGH MONDAY
*HIGHEST CONFIDENCE IN SNOW ACCUMULATION OVER NORTH-CENTRAL PA
INCLUDING THE ENDLESS MTNS ALONG THE NY BORDER
*HIGHEST CONFIDENCE IN ICE ACCUMULATION OVER EAST-CENTRAL PA
INCLUDING THE SOUTHERN POCONOS INTO THE LOWER SUSQUEHANNA VALLEY
THERE WAS NOT AS MUCH MODEL SPREAD AS IN THE LAST FEW CYCLES
BETWEEN THE NAM/SREF AND OTHER GLOBAL GUIDANCE. THEREFORE
CONTINUED TO EMPLOY A GENERAL MODEL COMPROMISE FOR MOST WEATHER
ELEMENTS WITH SLIGHT BIAS CORRECTION TO QPF AMTS...WHICH WHERE
BLENDED WITH CLIMO RATIOS AND WWD SNOW/ICE AMTS. THE STORM TOTAL
SNOWFALL CAME OUT ONLY SLIGHTLY MODIFIED WHILE THE ICE
ACCUMULATIONS WHERE INCREASED OVER EAST-CENTRAL PA -- AS THE
MODELS CONTINUE TO SIGNAL THE GREATEST RISK FOR FREEZING RAIN OVER
THE SOUTHERN POCONOS/SCHUYLKILL COUNTY VCNTY.
SHALLOW LOW LEVEL ARCTIC AIR WILL BE ADVANCING FROM NORTH TO SOUTH
UNDERNEATH A RELATIVELY WARMER NOSE OF AIR ALOFT. THIS WILL FAVOR
A RAIN TO WINTRY MIX PTYPE TRANSITION ALONG THE FRONTAL ZONE
BEFORE CHANGING OVER TO ALL SNOW BY MONDAY NIGHT AS COLD AIR
DEEPENS BEHIND THE BOUNDARY. THE WAVERING NATURE OF THE FREEZING
LINE AND MULTIPLE PTYPES MAKE THIS A RATHER COMPLEX AND DIFFICULT
FCST.
DESPITE SOME LINGERING UNCERTAINTY IN THE EVOLUTION OF THERMAL
PROFILES...FELT THAT IT WAS PRUDENT TO EXPAND THE WW ADVISORY
ANOTHER ROW OR TWO OF COUNTIES WEST AS IT APPEARS ICE ACCUMULATION
COVERAGE/POTENTIAL HAS INCREASED. MORNING COMMUTE IMPACTS WHERE
ALSO TAKEN INTO CONSIDERATION ESPECIALLY FOR THE HRB/YORK/LANCASTER
METRO AREAS.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
THE LARGE UPPER LEVEL TROUGH SHOULD MOVE OFF THE COAST AND OUT INTO
THE ATLANTIC TUESDAY EVENING. IN ITS WAKE...A WEAK RIDGE FOLLOWED BY
PREDOMINATELY ZONAL FLOW WILL OVERTAKE THE REGION WEDNESDAY. THE
WEST TO NORTHWESTERLY FLOW WILL BRING DRYING CONDITIONS AND A
CLEARING OF SKIES EARLY WEDNESDAY. HOWEVER THIS WILL BE SHORT LIVED
AS A MIDL LEVEL LOW AND ASSOCIATED TROUGH WILL MOVING INTO THE
REGION WEDNESDAY NIGHT INTO THURSDAY. THE UPPER LEVEL FLOW IS MORE
DIVERGENT...BUT MID LEVEL MOISTURE AND A WEAK SHORT WAVE SHOULD
COUPLE WITH UPSLOPE ENHANCEMENT TO BRING LIGHT SNOWFALLS THROUGH
THIS TIMEFRAME. CURRENT ENSEMBLES SHOW THE UPPER LEVEL LOW SHOULD
MOVE INTO EASTERN CANADA THURSDAY AS ITS CORRESPONDING TROUGH WILL
TREK THROUGH THE GREAT LAKES AND THROUGH PENNSYLVANIA THURSDAY
EVENING. THIS SYSTEM SHOULD BE MAINLY COLD AND DRY. CURRENT MID TO
LONG RANGE MODELS ARE IN FAIR AGREEMENT ON THE STRENGTH AND
POSITION OF THIS SYSTEM. SNOWFALL IS PROBABLE IN THE HIGHER
ELEVATIONS...INCLUDING THE WESTERN AND CENTRAL MOUNTAINS...THOUGH
WITH LOW QPF/S SNOWFALL SHOULD BE LIGHT. THE BIGGEST TAKEAWAY FROM
THIS SYSTEM IS THE STRONG COLD AIR ADVECTION THAT WILL FOLLOW IN
ITS WAKE AS AN ARCTIC AIRMASS WILL DROP DOWN...850MB TEMPS ARE
PROGGED IN THE -16C TO -23C RANGE.
OVERNIGHT LOWS THURSDAY NIGHT INTO FRIDAY MORNING COULD BE IN THE
UPPER SINGLE DIGITS THROUGH THE LOWER SUSQ...TO AROUND ZERO IN THE
NW MTNS. THE STRONG NORTHWEST GRADIENT COULD ALSO ALLOW FOR
PERSISTENT WINDS THROUGH THIS TIMEFRAME WHICH COULD ALLOW WIND
CHILLS TO BE A CONCERN. THIS COLD AIR SHOULD SIT OVER THE REGION
INTO THE WEEKEND. THE TIMING OF THE NEXT LOW TO MOVE THE REGION IS
IN QUESTION. CURRENTLY IT LOOKS TO FOLLOW QUICKLY BEHIND THE LATE
WORK WEEK SYSTEM....TRAVERSING THROUGH THE GREAT LAKES REGION BY
SATURDAY EVENING. THAT SYSTEM SEEMS SIMILAR TO THE PREVIOUS
STORM...THOUGH IT SEEMS TO HAVE BETTER DYNAMICS AND COULD BRING
ANOTHER SHOT OF SNOW TO CENTRAL PA SATURDAY NIGHT INTO SUNDAY. AS
THERE IS STILL SOME DISCONTINUITY AND VARIANCE IN TIMING...
CONFIDENCE IS LOW CURRENTLY.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
LOW PRES JUST SOUTH OF TOLEDO OHIO WILL TRACK ESEWD TO SWRN
PA/NRN WV BY 09/12Z THEN REDEVELOP OFF THE NC/VA COAST THROUGH
10/12Z. AS THE LOW TRACKS SOUTH OF CENTRAL PA AIRSPACE...A NEARLY
STATIONARY FRONTAL ZONE WILL BE PULLED SWD WITH SHALLOW LOW LEVEL
ARCTIC AIR NEAR THE SFC FILTERING INTO THE AIRSPACE FROM THE
NORTH AND NORTHEAST. THIS WILL SET THE STAGE FOR A WIDESPREAD
MIXED PRECIP EVENT TO UNFOLD FROM TONIGHT THROUGH MONDAY.
PRECIPITATION WILL LIKELY START AS PERIODS OF LIGHT RAIN ACROSS
THE NORTHERN TIER OF PENNSYLVANIA...BEFORE CHANGING TO MAINLY
LIGHT FREEZING RAIN ACROSS MOST OF THE CENTRAL MTNS AND SUSQ
VALLEY BETWEEN 09-12Z MONDAY. FURTHER SOUTHWEST ACROSS THE LAUREL
HIGHLANDS...THE VERY SHALLOW/DENSE COLDER AIR WON`T HAVE THE STEAM
TO CLIMB OVER THE CREST OF THE ALLEGHENIES FROM THE EAST...SO
PRECIP TYPE AT KJST WILL LIKELY STAY AS PLAIN RAIN UNTIL THE MID
TO LATE AFTERNOON HOURS WHEN THE COLDER AIR WILL INVADE FROM THE
N-NW.
AS THE LIGHT PRECIP BLOSSOMS OVER THE REGION AND FALLS THROUGH
THE SHALLOW COLDER AIR ACROSS THE NORTH...AND SOUTHEAST OF THE
ALLEGEHNIES TONIGHT...CIGS AND VSBYS WILL DECREASE STEADILY TO
MVFR THEN IFR AROUND 06-12Z MONDAY.
AGAIN...TO EMPHASIS SOME TIMING AND PRECIP TYPE ISSUES NOTED IN
THE PREVIOUS DISCUSSION - THE HRRR SHOWS PRECIP DEVELOPING OVER
THE NRN 1/3 AFTER 00Z WITH RAIN CHANGING TO MIXED PTYPES. COMPLEX
THERMAL PROFILES RESULT IN LOW CONFIDENCE IN TIMING OF PTYPE
ONSET/TRANSITION...HOWEVER NEARLY CERTAIN THAT THE OVERALL FLIGHT
CAT TREND WILL BE LOWER. LLVL E-NE FLOW ALSO SUGGEST LOWER CIGS
WILL DEVELOP OVER THE SERN AIRFIELDS.
OUTLOOK...
MON...WIDESPREAD MVFR/IFR IN MIXED PCPN.
TUE...AM LOW CIGS WITH PM IMPROVEMENT.
WED-THU...MVFR/IFR IN -SN.
THU NGT-FRI...GUSTY NW WINDS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 1 AM MONDAY TO 1 AM EST TUESDAY
FOR PAZ004>006-010>012-037-041-042-045-046-049>053-058.
WINTER WEATHER ADVISORY FROM 4 AM MONDAY TO 1 AM EST TUESDAY
FOR PAZ057-059-065-066.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...CERU
AVIATION...LAMBERT/STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
352 PM EST SUN FEB 8 2015
.SYNOPSIS...
LOW PRESSURE WILL TRACK THROUGH THE OHIO VALLEY INTO THE MID
ATLANTIC STATES TONIGHT THROUGH MONDAY...SPREADING MIXED
PRECIPITATION ACROSS CENTRAL PENNSYLVANIA. COLDER AIR WILL RETURN
FOR MIDWEEK BEFORE ANOTHER FRONTAL SYSTEM APPROACHES FOR THURSDAY
AND FRIDAY. BITTERLY COLD AIR WILL FOLLOW FOR THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL MIDNIGHT TONIGHT/...
LATEST HRRR INDICATES THE CAD PATTERN WILL REMAIN ENTRENCHED FROM
THE POCONOS INTO SERN PA AS COLD AIR FILTERS IN FROM THE NORTHEAST.
RADAR RETURNS HAVE INCREASED THIS AFTERNOON OVER THIS AREA WHICH
IS A GOOD INDICATION OF THE SHALLOW LOW LEVEL COLD AIR UNDERCUTTING
THE MORE ROBUST WAA ALOFT. VIRGA HAS BEEN REPORTED AT MDT WITH
DEWPOINT DEPRESSIONS STILL RUNNING ABOUT 10 DEGREES.
IN CONTRAST TO THE CAD IN LWR SUSQ VLY...MILD SW FLOW ACROSS THE
ALLEGHENIES HAS PUSHED TEMPS INTO THE 40S AND LOW 50S. THE STRONG
FRONTAL ZONE IS STILL NORTH OF THE NY BORDER...STRETCHING NE FROM
JUST SOUTH OF ERIE BETWEEN JHW/OLE.
ANY PRECIP THAT FALLS IN THE NORTHERN TIER EARLY TONIGHT SHOULD
BE MAINLY RAIN ALTHOUGH WILL NEED TO WATCH THE ENDLESS MTNS AND
SRN POCONO REGIONS...WHERE TEMPS WILL COOLING DOWN CLOSER TO
FREEZING.
&&
.SHORT TERM /MIDNIGHT TONIGHT THROUGH MONDAY NIGHT/...
*COMPLEX WINTER WEATHER SYSTEM TO IMPACT THE AREA LATE TONIGHT
THROUGH MONDAY
*HIGHEST CONFIDENCE IN SNOW ACCUMULATION OVER NORTH-CENTRAL PA
INCLUDING THE ENDLESS MTNS ALONG THE NY BORDER
*HIGHEST CONFIDENCE IN ICE ACCUMULATION OVER EAST-CENTRAL PA
INCLUDING THE SOUTHERN POCONOS INTO THE LOWER SUSQUEHANNA VALLEY
THERE WAS NOT AS MUCH MODEL SPREAD AS IN THE LAST FEW CYCLES
BETWEEN THE NAM/SREF AND OTHER GLOBAL GUIDANCE. THEREFORE
CONTINUED TO EMPLOY A GENERAL MODEL COMPROMISE FOR MOST WEATHER
ELEMENTS WITH SLIGHT BIAS CORRECTION TO QPF AMTS...WHICH WHERE
BLENDED WITH CLIMO RATIOS AND WWD SNOW/ICE AMTS. THE STORM TOTAL
SNOWFALL CAME OUT ONLY SLIGHTLY MODIFIED WHILE THE ICE
ACCUMULATIONS WHERE INCREASED OVER EAST-CENTRAL PA -- AS THE
MODELS CONTINUE TO SIGNAL THE GREATEST RISK FOR FREEZING RAIN OVER
THE SOUTHERN POCONOS/SCHUYLKILL COUNTY VCNTY.
SHALLOW LOW LEVEL ARCTIC AIR WILL BE ADVANCING FROM NORTH TO SOUTH
UNDERNEATH A RELATIVELY WARMER NOSE OF AIR ALOFT. THIS WILL FAVOR
A RAIN TO WINTRY MIX PTYPE TRANSITION ALONG THE FRONTAL ZONE
BEFORE CHANGING OVER TO ALL SNOW BY MONDAY NIGHT AS COLD AIR
DEEPENS BEHIND THE BOUNDARY. THE WAVERING NATURE OF THE FREEZING
LINE AND MULTIPLE PTYPES MAKE THIS A RATHER COMPLEX AND DIFFICULT
FCST.
DESPITE SOME LINGERING UNCERTAINTY IN THE EVOLUTION OF THERMAL
PROFILES...FELT THAT IT WAS PRUDENT TO EXPAND THE WW ADVISORY
ANOTHER ROW OR TWO OF COUNTIES WEST AS IT APPEARS ICE ACCUMULATION
COVERAGE/POTENTIAL HAS INCREASED. MORNING COMMUTE IMPACTS WHERE
ALSO TAKEN INTO CONSIDERATION ESPECIALLY FOR THE HRB/YORK/LANCASTER
METRO AREAS.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
THE LARGE UPPER LEVEL TROUGH SHOULD MOVE OFF THE COAST AND OUT INTO
THE ATLANTIC TUESDAY EVENING. IN ITS WAKE...A WEAK RIDGE FOLLOWED BY
PREDOMINATELY ZONAL FLOW WILL OVERTAKE THE REGION WEDNESDAY. THE
WEST TO NORTHWESTERLY FLOW WILL BRING DRYING CONDITIONS AND A
CLEARING OF SKIES EARLY WEDNESDAY. HOWEVER THIS WILL BE SHORT LIVED
AS A MIDL LEVEL LOW AND ASSOCIATED TROUGH WILL MOVING INTO THE
REGION WEDNESDAY NIGHT INTO THURSDAY. THE UPPER LEVEL FLOW IS MORE
DIVERGENT...BUT MID LEVEL MOISTURE AND A WEAK SHORT WAVE SHOULD
COUPLE WITH UPSLOPE ENHANCEMENT TO BRING LIGHT SNOWFALLS THROUGH
THIS TIMEFRAME. CURRENT ENSEMBLES SHOW THE UPPER LEVEL LOW SHOULD
MOVE INTO EASTERN CANADA THURSDAY AS ITS CORRESPONDING TROUGH WILL
TREK THROUGH THE GREAT LAKES AND THROUGH PENNSYLVANIA THURSDAY
EVENING. THIS SYSTEM SHOULD BE MAINLY COLD AND DRY. CURRENT MID TO
LONG RANGE MODELS ARE IN FAIR AGREEMENT ON THE STRENGTH AND
POSITION OF THIS SYSTEM. SNOWFALL IS PROBABLE IN THE HIGHER
ELEVATIONS...INCLUDING THE WESTERN AND CENTRAL MOUNTAINS...THOUGH
WITH LOW QPF/S SNOWFALL SHOULD BE LIGHT. THE BIGGEST TAKEAWAY FROM
THIS SYSTEM IS THE STRONG COLD AIR ADVECTION THAT WILL FOLLOW IN
ITS WAKE AS AN ARCTIC AIRMASS WILL DROP DOWN...850MB TEMPS ARE
PROGGED IN THE -16C TO -23C RANGE.
OVERNIGHT LOWS THURSDAY NIGHT INTO FRIDAY MORNING COULD BE IN THE
UPPER SINGLE DIGITS THROUGH THE LOWER SUSQ...TO AROUND ZERO IN THE
NW MTNS. THE STRONG NORTHWEST GRADIENT COULD ALSO ALLOW FOR
PERSISTENT WINDS THROUGH THIS TIMEFRAME WHICH COULD ALLOW WIND
CHILLS TO BE A CONCERN. THIS COLD AIR SHOULD SIT OVER THE REGION
INTO THE WEEKEND. THE TIMING OF THE NEXT LOW TO MOVE THE REGION IS
IN QUESTION. CURRENTLY IT LOOKS TO FOLLOW QUICKLY BEHIND THE LATE
WORK WEEK SYSTEM....TRAVERSING THROUGH THE GREAT LAKES REGION BY
SATURDAY EVENING. THAT SYSTEM SEEMS SIMILAR TO THE PREVIOUS
STORM...THOUGH IT SEEMS TO HAVE BETTER DYNAMICS AND COULD BRING
ANOTHER SHOT OF SNOW TO CENTRAL PA SATURDAY NIGHT INTO SUNDAY. AS
THERE IS STILL SOME DISCONTINUITY AND VARIANCE IN TIMING...
CONFIDENCE IS LOW CURRENTLY.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
LOW PRES OVER SRN MI WILL TRACK ESEWD TO SWRN PA/NRN WV BY 09/12Z
THEN REDEVELOP OFF THE NC/VA COAST THROUGH 10/12Z. AS THE LOW
TRACKS SOUTH OF CENTRAL PA AIRSPACE...A NEARLY STATIONARY FRONTAL
ZONE WILL BE PULLED SWD WITH SHALLOW LOW LEVEL ARCTIC AIR NEAR THE
SFC FILTERING INTO THE AIRSPACE FROM THE NORTH. THIS WILL SET THE
STAGE FOR A WIDESPREAD MIXED PRECIP EVENT TO UNFOLD FROM TONIGHT
THROUGH MONDAY.
UPDATED TAFS REFLECT CURRENT CONDITIONS WITH LOWEST CIGS ACROSS
THE NW 1/3 OF THE AIRSPACE. RADAR SHOWS PLENTY OF RETURNS ALOFT
BUT EXPECT A MAINLY DRY PERIOD THROUGH 00Z. THE HRRR SHOWS PRECIP
DEVELOPING OVER THE NRN 1/3 AFTER 00Z WITH RAIN CHANGING TO MIXED
PTYPES. COMPLEX THERMAL PROFILES RESULT IN LOW CONFIDENCE IN
TIMING OF PTYPE ONSET/TRANSITION...HOWEVER NEARLY CERTAIN THAT
THE OVERALL FLIGHT CAT TREND WILL BE LOWER. LLVL E-NE FLOW ALSO
SUGGEST LOWER CIGS WILL DEVELOP OVER THE SERN AIRFIELDS.
OUTLOOK...
MON...WIDESPREAD MVFR/IFR IN MIXED PCPN.
TUE...AM LOW CIGS WITH PM IMPROVEMENT.
WED-THU...MVFR/IFR IN -SN.
THU NGT-FRI...GUSTY NW WINDS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 1 AM MONDAY TO 1 AM EST TUESDAY
FOR PAZ004>006-010>012-037-041-042-045-046-049>053-058.
WINTER WEATHER ADVISORY FROM 4 AM MONDAY TO 1 AM EST TUESDAY
FOR PAZ057-059-065-066.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...CERU
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
336 PM EST SUN FEB 8 2015
.SYNOPSIS...
LOW PRESSURE WILL TRACK THROUGH THE OHIO VALLEY INTO THE MID
ATLANTIC STATES TONIGHT THROUGH MONDAY...SPREADING MIXED
PRECIPITATION ACROSS CENTRAL PENNSYLVANIA. COLDER AIR WILL RETURN
FOR MIDWEEK BEFORE ANOTHER FRONTAL SYSTEM APPROACHES FOR THURSDAY
AND FRIDAY. BITTERLY COLD AIR WILL FOLLOW FOR THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL MIDNIGHT TONIGHT/...
LATEST HRRR INDICATES THE CAD PATTERN WILL REMAIN ENTRENCHED FROM
THE POCONOS INTO SERN PA AS COLD AIR FILTERS IN FROM THE NORTHEAST.
RADAR RETURNS HAVE INCREASED THIS AFTERNOON OVER THIS AREA WHICH
IS A GOOD INDICATION OF THE SHALLOW LOW LEVEL COLD AIR UNDERCUTTING
THE MORE ROBUST WAA ALOFT. VIRGA HAS BEEN REPORTED AT MDT WITH
DEWPOINT DEPRESSIONS STILL RUNNING ABOUT 10 DEGREES.
IN CONTRAST TO THE CAD IN LWR SUSQ VLY...MILD SW FLOW ACROSS THE
ALLEGHENIES HAS PUSHED TEMPS INTO THE 40S AND LOW 50S. THE STRONG
FRONTAL ZONE IS STILL NORTH OF THE NY BORDER...STRETCHING NE FROM
JUST SOUTH OF ERIE BETWEEN JHW/OLE.
ANY PRECIP THAT FALLS IN THE NORTHERN TIER EARLY TONIGHT SHOULD
BE MAINLY RAIN ALTHOUGH WILL NEED TO WATCH THE ENDLESS MTNS AND
SRN POCONO REGIONS...WHERE TEMPS WILL COOLING DOWN CLOSER TO
FREEZING.
&&
.SHORT TERM /MIDNIGHT TONIGHT THROUGH MONDAY NIGHT/...
*COMPLEX WINTER WEATHER SYSTEM TO IMPACT THE AREA LATE TONIGHT
THROUGH MONDAY
*HIGHEST CONFIDENCE IN SNOW ACCUMULATION OVER NORTH-CENTRAL PA
INCLUDING THE ENDLESS MTNS ALONG THE NY BORDER
*HIGHEST CONFIDENCE IN ICE ACCUMULATION OVER EAST-CENTRAL PA
INCLUDING THE SOUTHERN POCONOS INTO THE LOWER SUSQUEHANNA VALLEY
THERE WAS NOT AS MUCH MODEL SPREAD AS IN THE LAST FEW CYCLES
BETWEEN THE NAM/SREF AND OTHER GLOBAL GUIDANCE. THEREFORE
CONTINUED TO EMPLOY A GENERAL MODEL COMPROMISE FOR MOST WEATHER
ELEMENTS WITH SLIGHT BIAS CORRECTION TO QPF AMTS...WHICH WHERE
BLENDED WITH CLIMO RATIOS AND WWD SNOW/ICE AMTS. THE STORM TOTAL
SNOWFALL CAME OUT ONLY SLIGHTLY MODIFIED WHILE THE ICE
ACCUMULATIONS WHERE INCREASED OVER EAST-CENTRAL PA -- AS THE
MODELS CONTINUE TO SIGNAL THE GREATEST RISK FOR FREEZING RAIN OVER
THE SOUTHERN POCONOS/SCHUYLKILL COUNTY VCNTY.
SHALLOW LOW LEVEL ARCTIC AIR WILL BE ADVANCING FROM NORTH TO SOUTH
UNDERNEATH A RELATIVELY WARMER NOSE OF AIR ALOFT. THIS WILL FAVOR
A RAIN TO WINTRY MIX PTYPE TRANSITION ALONG THE FRONTAL ZONE
BEFORE CHANGING OVER TO ALL SNOW BY MONDAY NIGHT AS COLD AIR
DEEPENS BEHIND THE BOUNDARY. THE WAVERING NATURE OF THE FREEZING
LINE AND MULTIPLE PTYPES MAKE THIS A RATHER COMPLEX AND DIFFICULT
FCST.
DESPITE SOME LINGERING UNCERTAINTY IN THE EVOLUTION OF THERMAL
PROFILES...FELT THAT IT WAS PRUDENT TO EXPAND THE WW ADVISORY
ANOTHER ROW OR TWO OF COUNTIES WEST AS IT APPEARS ICE ACCUMULATION
COVERAGE/POTENTIAL HAS INCREASED. MORNING COMMUTE IMPACTS WHERE
ALSO TAKEN INTO CONSIDERATION ESPECIALLY FOR THE HRB/YORK/LANCASTER
METRO AREAS.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE LARGE UPPER LEVEL TROUGH AND ITS CORRESPONDING SURFACE SYSTEM
SHOULD MOVE OFF THE COAST AND OUT INTO THE ATLANTIC TUESDAY NIGHT.
IN ITS WAKE...A WEAK RIDGE FOLLOWED BY PREDOMINATELY ZONAL FLOW WILL
OVERTAKE THE REGION WEDNESDAY. THE WEST TO NORTHWESTERLY FLOW WILL
BRING DRYING CONDITIONS AND A CLEARING OF SKIES EARLY WEDNESDAY.
HOWEVER THIS WILL BE SHORT LIVED AS ANOTHER TROUGH WILL TREK THROUGH
THE GREAT LAKES AND THROUGH PENNSYLVANIA BY THURSDAY. THIS
CLIPPER SHOULD BE COLD AND DRY. CURRENT MID TO LONG RANGE MODELS
ARE IN FAIR AGREEMENT ON THE STRENGTH AND POSITION OF THIS
SYSTEM. SNOWFALL IS PROBABLE...THOUGH WITH LOW QPF/S SNOWFALL
SHOULD BE LIGHT. HOWEVER THE BIGGEST TAKEAWAY FROM THIS SYSTEM IS
THE STRONG COLD AIR ADVECTION THAT WILL FOLLOW IN ITS WAKE AS AN
ARCTIC AIRMASS WILL DROP DOWN...850MB TEMPS ARE PROGGED IN THE
-16C TO -23C RANGE.
OVERNIGHT LOWS THURSDAY NIGHT INTO FRIDAY MORNING COULD BE IN THE
SINGLE DIGITS THROUGH THE LOWER SUSQ...TO NEAR -10 IN THE NW MTNS.
THE STRONG NORTHWEST GRADIENT COULD ALSO ALLOW FOR PERSISTENT
WINDS THROUGH THIS TIMEFRAME WHICH COULD ALLOW WIND CHILLS TO BE
LOW. THIS COLD AIR SHOULD SIT OVER THE REGION INTO THE WEEKEND AND
ANOTHER LOW SHOULD DROP DOWN THROUGH THE REGION LATE NEXT WEEKEND.
HOWEVER ENSEMBLES SHOW CONSIDERABLE DISCONTINUITY AND VARIANCE IN
TIMING SO CONFIDENCE IS LOW CURRENTLY.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
LOW PRES OVER SRN MI WILL TRACK ESEWD TO SWRN PA/NRN WV BY 09/12Z
THEN REDEVELOP OFF THE NC/VA COAST THROUGH 10/12Z. AS THE LOW
TRACKS SOUTH OF CENTRAL PA AIRSPACE...A NEARLY STATIONARY FRONTAL
ZONE WILL BE PULLED SWD WITH SHALLOW LOW LEVEL ARCTIC AIR NEAR THE
SFC FILTERING INTO THE AIRSPACE FROM THE NORTH. THIS WILL SET THE
STAGE FOR A WIDESPREAD MIXED PRECIP EVENT TO UNFOLD FROM TONIGHT
THROUGH MONDAY.
UPDATED TAFS REFLECT CURRENT CONDITIONS WITH LOWEST CIGS ACROSS
THE NW 1/3 OF THE AIRSPACE. RADAR SHOWS PLENTY OF RETURNS ALOFT
BUT EXPECT A MAINLY DRY PERIOD THROUGH 00Z. THE HRRR SHOWS PRECIP
DEVELOPING OVER THE NRN 1/3 AFTER 00Z WITH RAIN CHANGING TO MIXED
PTYPES. COMPLEX THERMAL PROFILES RESULT IN LOW CONFIDENCE IN
TIMING OF PTYPE ONSET/TRANSITION...HOWEVER NEARLY CERTAIN THAT
THE OVERALL FLIGHT CAT TREND WILL BE LOWER. LLVL E-NE FLOW ALSO
SUGGEST LOWER CIGS WILL DEVELOP OVER THE SERN AIRFIELDS.
OUTLOOK...
MON...WIDESPREAD MVFR/IFR IN MIXED PCPN.
TUE...AM LOW CIGS WITH PM IMPROVEMENT.
WED-THU...MVFR/IFR IN -SN.
THU NGT-FRI...GUSTY NW WINDS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 1 AM MONDAY TO 1 AM EST TUESDAY
FOR PAZ004>006-010>012-037-041-042-045-046-049>053-058.
WINTER WEATHER ADVISORY FROM 4 AM MONDAY TO 1 AM EST TUESDAY
FOR PAZ057-059-065-066.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...CERU/MARTIN
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1113 AM EST SUN FEB 8 2015
.SYNOPSIS...
LOW PRESSURE WILL SLIDE THROUGH THE OHIO VALLEY AND INTO THE MID
ATLANTIC STATES TODAY AND MONDAY. COLDER AIR WILL RETURN FOR
MIDWEEK BEFORE ANOTHER FRONTAL SYSTEM APPROACHES FOR THURSDAY AND
FRIDAY. BITTERLY COLD AIR WILL FOLLOW FOR THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
MILD SW FLOW PUSHING TEMPS WELL INTO THE 40S ALONG AND WEST OF THE
ALLEGHENIES. MEANWHILE LLVL CAD WITH LGT ENE WINDS MAY LIMIT MAX
TEMPS OVER THE SE ZONES AND HAVE CUT BACK A FEW DEGREES FROM
PREVIOUS MAXES. ALSO CUT BACK POPS FOR --RA TO JUST THE FAR NRN
TIER BASED ON THE LATEST HRRR.
ALSO ISSUED UPDATED DAY 2 FCST THROUGH TOMORROW NIGHT. WE WILL BE
CONSIDERING EXPANDING THE WW ADVISORY WITH THE AFTERNOON FCST.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH MONDAY NIGHT/...
LOW PRESSURE MOVING THRU THE OH VALLEY WILL BRING RAIN TO THE AREA
TONIGHT AND TEMPS WILL GRADUALLY LOWER THROUGH THE NIGHT - ESP IN
THE NORTH WHERE IT SHOULD GO TO SNOW FAIRLY QUICKLY. THE
INDIVIDUAL MODEL QPFS AND SREF QPF MEANS AND HPC GUIDANCE ALL
POINT TO BETWEEN A QUARTER AND THREE QUARTERS OF AN INCH OF
LIQUID OUT OF THIS STORM THROUGH THE NEXT 48 HOURS.
IT IS QUITE AN UNUSUAL PROGRESSION OF EVENTS...THE RAIN MAY TURN
TO FREEZING RAIN LATE TONIGHT OVER THE EASTERN THIRD TO HALF OF
THE AREA AS LLVL COLD AIR SEEPS IN FROM THE E/NE. STILL HAVE MY
DOUBTS THAT WE CAN HAVE A SIGNIFICANT/ACCUMULATING AMOUNT OF
FREEZING RAIN AFTER RAIN STARTS AND TEMPS ARE ABOVE FREEZING.
HOWEVER...AFTER COLLABORATION WITH NEIGHBORING OFFICES...A WINT
WX ADVY FOR SNOW HAS BEEN ISSUED FOR THE N AND A WINT WX ADVY FOR
MAINLY ICE ACCUMS HAS BEEN POSTED FOR THE EAST-CENTRAL COS.
SNOWFALL IN THE N/NE COULD REACH 6 OR MORE INCHES OVER THE NEXT 48
HRS...BUT ANY 12 OR 24 HR STRETCH DOES NOT SEEM TO WARRANT A
WARNING.
THE TIMING OF THE EXPECTED TURN TO ZR IN THE E-C WILL BE RIGHT
BEFORE OR DURING THE RUSH HOUR ON MONDAY. THUS...HAVE TAKEN A
STEP AND ONLY INCLUDED ROUGHLY HALF OF THE AREA OF WHERE THE ZR
MAY BECOME WIDESPREAD. LATER SHIFTS MAY NEED TO ADD ONTO THIS
FIRST CUT AT HITTING THE MOST-LIKELY AREA TO SEE IMPACT FROM ZR.
THE PRECIP WILL THEN TURN TO SNOW OVER ALL OF THE AREA AS THE DAY
ENDS ON MONDAY.
LOW PRESSURE LINGERS OVER PA MON NIGHT BUT THE UPPER TROUGH SHOULD
BE TO THE EAST OF THE AREA BEFORE TUES MORNING.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE LARGE UPPER LEVEL TROUGH AND ITS CORRESPONDING SURFACE SYSTEM
SHOULD MOVE OFF THE COAST AND OUT INTO THE ATLANTIC TUESDAY NIGHT.
IN ITS WAKE...A WEAK RIDGE FOLLOWED BY PREDOMINATELY ZONAL FLOW WILL
OVERTAKE THE REGION WEDNESDAY. THE WEST TO NORTHWESTERLY FLOW WILL
BRING DRYING CONDITIONS AND A CLEARING OF SKIES EARLY WEDNESDAY.
HOWEVER THIS WILL BE SHORT LIVED AS ANOTHER TROUGH WILL TREK THROUGH
THE GREAT LAKES AND THROUGH PENNSYLVANIA BY THURSDAY. THIS
CLIPPER SHOULD BE COLD AND DRY. CURRENT MID TO LONG RANGE MODELS
ARE IN FAIR AGREEMENT ON THE STRENGTH AND POSITION OF THIS
SYSTEM. SNOWFALL IS PROBABLE...THOUGH WITH LOW QPF/S SNOWFALL
SHOULD BE LIGHT. HOWEVER THE BIGGEST TAKEAWAY FROM THIS SYSTEM IS
THE STRONG COLD AIR ADVECTION THAT WILL FOLLOW IN ITS WAKE AS AN
ARCTIC AIRMASS WILL DROP DOWN...850MB TEMPS ARE PROGGED IN THE
-16C TO -23C RANGE.
OVERNIGHT LOWS THURSDAY NIGHT INTO FRIDAY MORNING COULD BE IN THE
SINGLE DIGITS THROUGH THE LOWER SUSQ...TO NEAR -10 IN THE NW MTNS.
THE STRONG NORTHWEST GRADIENT COULD ALSO ALLOW FOR PERSISTENT
WINDS THROUGH THIS TIMEFRAME WHICH COULD ALLOW WIND CHILLS TO BE
LOW. THIS COLD AIR SHOULD SIT OVER THE REGION INTO THE WEEKEND AND
ANOTHER LOW SHOULD DROP DOWN THROUGH THE REGION LATE NEXT WEEKEND.
HOWEVER ENSEMBLES SHOW CONSIDERABLE DISCONTINUITY AND VARIANCE IN
TIMING SO CONFIDENCE IS LOW CURRENTLY.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
LOW PRES OVER SRN MI WILL TRACK ESEWD TO SWRN PA/NRN WV BY 09/12Z
THEN REDEVELOP OFF THE NC/VA COAST THROUGH 10/12Z. AS THE LOW
TRACKS SOUTH OF CENTRAL PA AIRSPACE...A NEARLY STATIONARY FRONTAL
ZONE WILL BE PULLED SWD WITH SHALLOW LOW LEVEL ARCTIC AIR NEAR THE
SFC FILTERING INTO THE AIRSPACE FROM THE NORTH. THIS WILL SET THE
STAGE FOR A WIDESPREAD MIXED PRECIP EVENT TO UNFOLD FROM TONIGHT
THROUGH MONDAY.
UPDATED TAFS REFLECT CURRENT CONDITIONS WITH LOWEST CIGS ACROSS
THE NW 1/3 OF THE AIRSPACE. RADAR SHOWS PLENTY OF RETURNS ALOFT
BUT EXPECT A MAINLY DRY PERIOD THROUGH 00Z. THE HRRR SHOWS PRECIP
DEVELOPING OVER THE NRN 1/3 AFTER 00Z WITH RAIN CHANGING TO MIXED
PTYPES. COMPLEX THERMAL PROFILES RESULT IN LOW CONFIDENCE IN
TIMING OF PTYPE ONSET/TRANSITION...HOWEVER NEARLY CERTAIN THAT
THE OVERALL FLIGHT CAT TREND WILL BE LOWER. LLVL E-NE FLOW ALSO
SUGGEST LOWER CIGS WILL DEVELOP OVER THE SERN AIRFIELDS.
OUTLOOK...
MON...WIDESPREAD MVFR/IFR IN MIXED PCPN.
TUE...AM LOW CIGS WITH PM IMPROVEMENT.
WED-THU...MVFR/IFR IN -SN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 1 AM MONDAY TO 1 AM EST TUESDAY
FOR PAZ005-006-037-041-042.
WINTER WEATHER ADVISORY FROM 6 AM MONDAY TO 1 AM EST TUESDAY
FOR PAZ046-051>053-058.
&&
$$
SYNOPSIS...DANGELO/STEINBUGL
NEAR TERM...DANGELO/STEINBUGL
SHORT TERM...DANGELO/STEINBUGL
LONG TERM...CERU/MARTIN
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1133 PM EST SAT FEB 7 2015
.SYNOPSIS...
LOW PRESSURE DEVELOPING OVER THE UPPER MIDWEST WILL TRACK EAST-
SOUTHEAST ACROSS THE OHIO VALLEY AND OFF THE MID ATLANTIC COAST BY
MONDAY. COLDER AIR WILL RETURN FOR MIDWEEK BEFORE ANOTHER FRONTAL
SYSTEM APPROACHES FOR THURSDAY AND FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
SATELLITE CONTINUES TO SHOW MAINLY MID AND HIGH CLOUDS BLEEDING
SOUTHEAST INTO THE REGION FROM THE GR LAKES. MESO ANAL PLACES THE
WARM FRONT ALONG OR JUST NORTH OF THE NY BORDER WHERE TEMPS DIP TO
FREEZING OR BELOW AND LOW CLOUDS ARE SERVING UP SOME PATCHES OF
LIGHT SNOW.
IN THE NEAR TERM THE HRRR HAS BACKED OFF THE SMALL PATCH OF LIGHT
RAIN THAT IT HAD CROSSING NRN PA. NO REASON TO DEVIATE FROM THE
CURRENT FORECAST OF A MAINLY DRY OVERNIGHT.
MIN TEMPS TONIGHT SHOULD HOLD WITHIN A FEW DEGREES EITHER SIDE OF
32F.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
*COMPLEX WINTER WEATHER SYSTEM TO IMPACT THE AREA SUNDAY-MONDAY
*GREATEST RISK OF SNOW AND ICE ACCUMULATION OVER NORTH-CENTRAL PA
A PACIFIC SHORTWAVE MOVING THROUGH THE INTER MOUNTAIN WEST AND
NORTHERN HIGH PLAINS TONIGHT WILL ADVANCE RAPIDLY INTO THE
MIDWEST BY EARLY SUNDAY. THE MODEL SPREAD BEGINS TO GROW AS THE
ENERGY AMPLIFIES TOWARD THE EASTERN U.S...DRIVING A SFC-850 LOW
THROUGH THE UPPER OHIO VALLEY INTO THE NORTHERN MID ATLANTIC
STATES ALONG A STRONG FRONTAL ZONE. THE PRIMARY SFC LOW IS FCST
TO REACH SW PA AND NRN WV BY 09/12Z BEFORE REDEVELOPING OFF THE
VA/NC COAST BY THE END OF THE PERIOD.
STAYED PRETTY CLOSE TO CONSENSUS WITH RESPECT TO THE LATEST
GUIDANCE AND USED A MULTI-MODEL BLEND FOR TEMPERATURES. REDUCED
MEAN QPF BY 25% BASED ON RECENT INTERNAL BIAS CORRECTION. THIS
KEPT GOOD CONTINUITY WITH THE GRIDDED 48-HOUR TOTAL SNOW AND ICE
ACCUMULATIONS DERIVED WITH THE LATE MORNING UPDATE. THE MAIN
COMPLICATING FACTOR IN THE FCST IS THE NWD EXTENT OF THE RAIN/SNOW
LINE. CONCERNING SNOW ACCUMULATIONS...IT APPEARS THE RISK IS
MOST LIKELY TO THE DOWNSIDE (LESSER AMOUNTS) WITH A MORE ROBUST
WARM NOSE ALOFT POSSIBLY SURGING INTO NY STATE...WHICH WOULD
LIMIT SNOW ACCUMULATIONS ALONG I-80 TO THE NY BORDER. THE
NAM/SREF ARE SLIGHTLY MORE BULLISH ON A WARMER SOLUTION WHICH CAN
LKLY BE ATTRIBUTED TO A MORE NORTHERLY SFC LOW TRACK...ALTHOUGH
THE MOST RECENT MODEL RUNS HAVE GRADUALLY TRENDED FARTHER SOUTH
TOWARD THE 12Z GFS/ECMWF/UKMET.
THE GREATEST RISK FOR SIGNIFICANT SNOW ACCUMS OVER A LONG
DURATION (2 DAY PERIOD) REMAINS OVER THE FAR NCENTRAL AND NERN
ZONES INTO NY STATE...WHERE BEST FGEN FORCING WILL OCCUR NORTH OF
SFC LOW TRACK. THE EXPECTATION IS THAT SHALLOW LOW LEVEL ARCTIC
AIR WILL LKLY BE FILTERING SWD FROM LATE SUNDAY INTO MONDAY
THROUGH SRN NY INTO NRN PA AND UNDERCUTTING THE MARGINALLY WARMER
NOSE OF AIR AROUND 850MB. THIS WILL INTRODUCE A FREEZING RAIN/ICE
THREAT ON THE NORTHERN SIDE OF THE PRECIP SHIELD. THE 09Z SREF
APPEARS TO BE PICKING UP ON A SIGNAL FOR ICE ACCUM FROM THE SRN
POCONOS INTO SCHUYLKILL COUNTY WHICH WAS ALSO REFLECTED WITH AN
INCREASE IN THE LATEST WWD -- AND THEREFORE BUMPED UP FZRA AMTS
INTO THE 0.10-0.25 RANGE.
NO HEADLINES WERE ISSUED THIS AFTERNOON BUT LATER SHIFTS WILL
PROBABLY BE CONSIDERING A WINTER WX ADVISORY. CONFIDENCE WITH THE
FCST WITH THIS EVENT IS AVG WITH MINOR CHANGES EXPECTED AS THE
EVENT DRAWS CLOSER IN TIME.
PTYPES GRADUALLY TRANSITION FROM SNOW/RAIN/MIX TO ALL SNOW BY
MONDAY NIGHT AS THE UPPER TROUGH AXIS DIGS INTO AND PIVOTS THROUGH
THE MID ATLC REGION.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE LARGE UPPER LEVEL TROUGH AND ITS CORRESPONDING SURFACE SYSTEM
SHOULD MOVE OFF THE COAST AND OUT INTO THE ATLANTIC TUESDAY NIGHT.
IN ITS WAKE...A WEAK RIDGE FOLLOWED BY PREDOMINATELY ZONAL FLOW WILL
OVERTAKE THE REGION WEDNESDAY. THE WEST TO NORTHWESTERLY FLOW WILL
BRING DRYING CONDITIONS AND A CLEARING OF SKIES EARLY WEDNESDAY.
HOWEVER THIS WILL BE SHORT LIVED AS ANOTHER TROUGH WILL TREK THROUGH
THE GREAT LAKES AND THROUGH PENNSYLVANIA BY THURSDAY. THIS
CLIPPER SHOULD BE COLD AND DRY. CURRENT MID TO LONG RANGE MODELS
ARE IN FAIR AGREEMENT ON THE STRENGTH AND POSITION OF THIS
SYSTEM. SNOWFALL IS PROBABLE...THOUGH WITH LOW QPF/S SNOWFALL
SHOULD BE LIGHT. HOWEVER THE BIGGEST TAKEAWAY FROM THIS SYSTEM IS
THE STRONG COLD AIR ADVECTION THAT WILL FOLLOW IN ITS WAKE AS AN
ARCTIC AIRMASS WILL DROP DOWN...850MB TEMPS ARE PROGGED IN THE
-16C TO -23C RANGE.
OVERNIGHT LOWS THURSDAY NIGHT INTO FRIDAY MORNING COULD BE IN THE
SINGLE DIGITS THROUGH THE LOWER SUSQ...TO NEAR -10 IN THE NW MTNS.
THE STRONG NORTHWEST GRADIENT COULD ALSO ALLOW FOR PERSISTENT
WINDS THROUGH THIS TIMEFRAME WHICH COULD ALLOW WIND CHILLS TO BE
LOW. THIS COLD AIR SHOULD SIT OVER THE REGION INTO THE WEEKEND AND
ANOTHER LOW SHOULD DROP DOWN THROUGH THE REGION LATE NEXT WEEKEND.
HOWEVER ENSEMBLES SHOW CONSIDERABLE DISCONTINUITY AND VARIANCE IN
TIMING SO CONFIDENCE IS LOW CURRENTLY.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
EAST-WEST FRONTAL BOUNDARY REMAINS NEARLY STATIONARY JUST NORTH
OF THE PA/NY BORDER AT 04Z. THIS BOUNDARY WILL DRIFT VERY SLOWLY
TO THE SOUTH THROUGH SUNDAY WITH SHALLOW COLD AIR OOZING SOUTH
ACROSS THE REGION...BRINGING A GRADUAL DECREASE IN CIG HEIGHTS AND
VSBYS ACROSS THE NRN MTNS OF PENN /INVOF KBFD/.
ASIDE FROM SOME PATCHY LIGHT DRIZZLE...FREEZING DRIZZLE OR LIGHT
SNOW NEAR AND TO THE NORTH OF A LINE FROM KBFD TO KIPT AFTER 11Z
SUNDAY...CONDITIONS WILL REMAIN DRY. AN AREA OF STEADY...LIGHT
RAIN/MIXED PRECIP AND SNOW WILL EXPAND SWD ACROSS CENTRAL AND
NORTHERN PENNSYLVANIA AIRFIELDS SUNDAY AFTERNOON INTO EARLY SUNDAY
NIGHT. MOST OF THE LIGHT PRECIP THROUGH LATE SUNDAY NIGHT WILL
STAY MAINLY RAIN TO THE SOUTH OF INTERSTATE 80.
CIG HEIGHTS HAVE RECENTLY DROPPED INTO THE UPPER END OF MVFR
AT KBFD...AND WILL GRADUALLY LOWER INTO THIS SAME RANGE TWD
DAYBREAK FOR KJST...KIPT AND KUNV. VFR WILL PERSIST ACROSS THE
SOUTHEASTERN THIRD OF THE STATE THROUGH ABOUT 16Z SUNDAY BEFORE
DIPPING TO MVFR.
MENTIONED LLWS OVERNIGHT TONIGHT FROM THE LAUREL HIGHLANDS /KJST/
NE THROUGH KAOO...KUNV...AND KIPT AS THE AXIS OF A SWRLY LOW
LEVEL JET NOSES NE FROM THE OHIO RIVER VALLEY.
THE INCREASED LOW LVL MOISTURE AND SHALLOW COLD AIR JUST BEHIND
THE COLD FRONT SAGGING SOUTH FROM NEW YORK STATE...WILL LIKELY
LEAD TO IFR CIGS DEVELOPING AT KBFD SUNDAY MORNING /AFT
12Z/...THEN WORKING THEIR WAY SLOWLY SOUTH DURING THE DAY. LIFR IS
POSSIBLE AT KBFD BY 19Z SUNDAY AS STEADIER LIGHT PRECIP /LIGHT
RAIN OR ICE PELLETS/ DEVELOPS.
OUTLOOK...
SUN...RAIN/LOW CIGS POSSIBLE...MAINLY KBFD.
MON...WIDESPREAD MVFR/IFR IN MIXED PCPN...GRADUALLY CHANGING TO
SNOW ACROSS CENTRAL AND NORTHERN PENN AIRFIELDS.
TUE...AM LOW CIGS POSS W MTNS.
WED...PM SHSN POSSIBLE NW MTNS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...STEINBUGL
LONG TERM...CERU/MARTIN
AVIATION...LAMBERT
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1120 PM EST SAT FEB 7 2015
.SYNOPSIS...
LOW PRESSURE DEVELOPING OVER THE UPPER MIDWEST WILL TRACK EAST-
SOUTHEAST ACROSS THE OHIO VALLEY AND OFF THE MID ATLANTIC COAST BY
MONDAY. COLDER AIR WILL RETURN FOR MIDWEEK BEFORE ANOTHER FRONTAL
SYSTEM APPROACHES FOR THURSDAY AND FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
SATELLITE CONTINUES TO SHOW MAINLY MID AND HIGH CLOUDS BLEEDING
SOUTHEAST INTO THE REGION FROM THE GR LAKES. MESO ANAL PLACES THE
WARM FRONT ALONG OR JUST NORTH OF THE NY BORDER WHERE TEMPS DIP TO
FREEZING OR BELOW AND LOW CLOUDS ARE SERVING UP SOME PATCHES OF
LIGHT SNOW.
IN THE NEAR TERM THE HRRR HAS BACKED OFF THE SMALL PATCH OF LIGHT
RAIN THAT IT HAD CROSSING NRN PA. NO REASON TO DEVIATE FROM THE
CURRENT FORECAST OF A MAINLY DRY OVERNIGHT.
MIN TEMPS TONIGHT SHOULD HOLD WITHIN A FEW DEGREES EITHER SIDE OF
32F.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
*COMPLEX WINTER WEATHER SYSTEM TO IMPACT THE AREA SUNDAY-MONDAY
*GREATEST RISK OF SNOW AND ICE ACCUMULATION OVER NORTH-CENTRAL PA
A PACIFIC SHORTWAVE MOVING THROUGH THE INTER MOUNTAIN WEST AND
NORTHERN HIGH PLAINS TONIGHT WILL ADVANCE RAPIDLY INTO THE
MIDWEST BY EARLY SUNDAY. THE MODEL SPREAD BEGINS TO GROW AS THE
ENERGY AMPLIFIES TOWARD THE EASTERN U.S...DRIVING A SFC-850 LOW
THROUGH THE UPPER OHIO VALLEY INTO THE NORTHERN MID ATLANTIC
STATES ALONG A STRONG FRONTAL ZONE. THE PRIMARY SFC LOW IS FCST
TO REACH SW PA AND NRN WV BY 09/12Z BEFORE REDEVELOPING OFF THE
VA/NC COAST BY THE END OF THE PERIOD.
STAYED PRETTY CLOSE TO CONSENSUS WITH RESPECT TO THE LATEST
GUIDANCE AND USED A MULTI-MODEL BLEND FOR TEMPERATURES. REDUCED
MEAN QPF BY 25% BASED ON RECENT INTERNAL BIAS CORRECTION. THIS
KEPT GOOD CONTINUITY WITH THE GRIDDED 48-HOUR TOTAL SNOW AND ICE
ACCUMULATIONS DERIVED WITH THE LATE MORNING UPDATE. THE MAIN
COMPLICATING FACTOR IN THE FCST IS THE NWD EXTENT OF THE RAIN/SNOW
LINE. CONCERNING SNOW ACCUMULATIONS...IT APPEARS THE RISK IS
MOST LIKELY TO THE DOWNSIDE (LESSER AMOUNTS) WITH A MORE ROBUST
WARM NOSE ALOFT POSSIBLY SURGING INTO NY STATE...WHICH WOULD
LIMIT SNOW ACCUMULATIONS ALONG I-80 TO THE NY BORDER. THE
NAM/SREF ARE SLIGHTLY MORE BULLISH ON A WARMER SOLUTION WHICH CAN
LKLY BE ATTRIBUTED TO A MORE NORTHERLY SFC LOW TRACK...ALTHOUGH
THE MOST RECENT MODEL RUNS HAVE GRADUALLY TRENDED FARTHER SOUTH
TOWARD THE 12Z GFS/ECMWF/UKMET.
THE GREATEST RISK FOR SIGNIFICANT SNOW ACCUMS OVER A LONG
DURATION (2 DAY PERIOD) REMAINS OVER THE FAR NCENTRAL AND NERN
ZONES INTO NY STATE...WHERE BEST FGEN FORCING WILL OCCUR NORTH OF
SFC LOW TRACK. THE EXPECTATION IS THAT SHALLOW LOW LEVEL ARCTIC
AIR WILL LKLY BE FILTERING SWD FROM LATE SUNDAY INTO MONDAY
THROUGH SRN NY INTO NRN PA AND UNDERCUTTING THE MARGINALLY WARMER
NOSE OF AIR AROUND 850MB. THIS WILL INTRODUCE A FREEZING RAIN/ICE
THREAT ON THE NORTHERN SIDE OF THE PRECIP SHIELD. THE 09Z SREF
APPEARS TO BE PICKING UP ON A SIGNAL FOR ICE ACCUM FROM THE SRN
POCONOS INTO SCHUYLKILL COUNTY WHICH WAS ALSO REFLECTED WITH AN
INCREASE IN THE LATEST WWD -- AND THEREFORE BUMPED UP FZRA AMTS
INTO THE 0.10-0.25 RANGE.
NO HEADLINES WERE ISSUED THIS AFTERNOON BUT LATER SHIFTS WILL
PROBABLY BE CONSIDERING A WINTER WX ADVISORY. CONFIDENCE WITH THE
FCST WITH THIS EVENT IS AVG WITH MINOR CHANGES EXPECTED AS THE
EVENT DRAWS CLOSER IN TIME.
PTYPES GRADUALLY TRANSITION FROM SNOW/RAIN/MIX TO ALL SNOW BY
MONDAY NIGHT AS THE UPPER TROUGH AXIS DIGS INTO AND PIVOTS THROUGH
THE MID ATLC REGION.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE LARGE UPPER LEVEL TROUGH AND ITS CORRESPONDING SURFACE SYSTEM
SHOULD MOVE OFF THE COAST AND OUT INTO THE ATLANTIC TUESDAY NIGHT.
IN ITS WAKE...A WEAK RIDGE FOLLOWED BY PREDOMINATELY ZONAL FLOW WILL
OVERTAKE THE REGION WEDNESDAY. THE WEST TO NORTHWESTERLY FLOW WILL
BRING DRYING CONDITIONS AND A CLEARING OF SKIES EARLY WEDNESDAY.
HOWEVER THIS WILL BE SHORT LIVED AS ANOTHER TROUGH WILL TREK THROUGH
THE GREAT LAKES AND THROUGH PENNSYLVANIA BY THURSDAY. THIS
CLIPPER SHOULD BE COLD AND DRY. CURRENT MID TO LONG RANGE MODELS
ARE IN FAIR AGREEMENT ON THE STRENGTH AND POSITION OF THIS
SYSTEM. SNOWFALL IS PROBABLE...THOUGH WITH LOW QPF/S SNOWFALL
SHOULD BE LIGHT. HOWEVER THE BIGGEST TAKEAWAY FROM THIS SYSTEM IS
THE STRONG COLD AIR ADVECTION THAT WILL FOLLOW IN ITS WAKE AS AN
ARCTIC AIRMASS WILL DROP DOWN...850MB TEMPS ARE PROGGED IN THE
-16C TO -23C RANGE.
OVERNIGHT LOWS THURSDAY NIGHT INTO FRIDAY MORNING COULD BE IN THE
SINGLE DIGITS THROUGH THE LOWER SUSQ...TO NEAR -10 IN THE NW MTNS.
THE STRONG NORTHWEST GRADIENT COULD ALSO ALLOW FOR PERSISTENT
WINDS THROUGH THIS TIMEFRAME WHICH COULD ALLOW WIND CHILLS TO BE
LOW. THIS COLD AIR SHOULD SIT OVER THE REGION INTO THE WEEKEND AND
ANOTHER LOW SHOULD DROP DOWN THROUGH THE REGION LATE NEXT WEEKEND.
HOWEVER ENSEMBLES SHOW CONSIDERABLE DISCONTINUITY AND VARIANCE IN
TIMING SO CONFIDENCE IS LOW CURRENTLY.
&&
.AVIATION /04Z SUNDAY THROUGH THURSDAY/...
EAST-WEST FRONTAL BOUNDARY REMAINS NEARLY STATIONARY JUST NORTH
OF THE PA/NY BORDER AT 04Z. THIS BOUNDARY WILL DRIFT VERY SLOWLY
TO THE SOUTH THROUGH SUNDAY WITH SHALLOW COLD AIR OOZING SOUTH
ACROSS THE REGION...BRINGING A GRADUAL DECREASE IN CIG HEIGHTS AND
VSBYS ACROSS THE NRN MTNS OF PENN /INVOF KBFD/.
ASIDE FROM SOME PATCHY LIGHT DRIZZLE...FREEZING DRIZZLE OR LIGHT
SNOW NEAR AND TO THE NORTH OF A LINE FROM KBFD TO KIPT AFTER 11Z
SUNDAY...CONDITIONS WILL REMAIN DRY. AN AREA OF STEADY...LIGHT
RAIN/MIXED PRECIP AND SNOW WILL EXPAND SWD ACROSS CENTRAL AND
NORTHERN PENNSYLVANIA AIRFIELDS SUNDAY AFTERNOON INTO EARLY SUNDAY
NIGHT. MOST OF THE LIGHT PRECIP THROUGH LATE SUNDAY NIGHT WILL
STAY MAINLY RAIN TO THE SOUTH OF INTERSTATE 80.
CIG HEIGHTS AND VSBYS WILL DROP TO MVFR FIRST THIS EVENING AT
KBFD...THEN AFTER MIDNIGHT-DAYBREAK FOR KJST...KIPT AND KUNV. VFR
WILL PERSIST ACROSS THE SOUTHERN HALF OF THE STATE THROUGH 12Z
SUNDAY BEFORE DIPPING TO MVFR.
MENTIONED LLWS OVERNIGHT TONIGHT FROM THE LAUREL HIGHLANDS /KJST/
NE THROUGH KAOO.KUNV AND KIPT...AS THE AXIS OF A SWRLY LOW LEVEL
JET NOSES NE FROM THE OHIO RIVER VALLEY.
THE INCREASED LOW LVL MOISTURE AND SHALLOW COLD AIR JUST BEHIND
THE COLD FRONT SAGGING SD FROM NEW YORK STATE...WILL LIKELY LEAD
TO IFR CIGS DEVELOPING AT KBFD SUNDAY MORNING /AFT 12Z/...THEN
WORKING THEIR WAY SLOWLY SOUTH DURING THE DAY.
OUTLOOK...
SUN...RAIN/LOW CIGS POSSIBLE...MAINLY KBFD.
MON...WIDESPREAD MVFR/IFR IN MIXED PCPN.
TUE...AM LOW CIGS POSS W MTNS.
WED...PM SHSN POSSIBLE NW MTNS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...STEINBUGL
LONG TERM...CERU/MARTIN
AVIATION...LAMBERT
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
826 PM EST MON FEB 9 2015
.SYNOPSIS...
IN THE WAKE OF A COLD FRONT...DRY HIGH PRESSURE WILL BUILD INTO THE
REGION ON TUESDAY AND LINGER THROUGH WEDNESDAY. AN ARCTIC COLD FRONT
WILL REACH THE MOUNTAINS ON THURSDAY WITH A COLD AIR MASS FILTERING
INTO THE REGION FRIDAY THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 825 PM...HAVE UPDATED THE FCST TO REMOVE MENTION OF THUNDER
AND INCREASE POPS ACRS THE ERN HALF OF THE CWFA TO LIKELY BASED ON
RADAR TRENDS. THE AXIS OF THE MID LVL SHORTWAVE TROF IS IN LINE WITH
THE BACK EDGE OF PRECIP. SO EXPECT POPS TO TAPER OFF FROM WEST TO
EAST THIS EVENING. THE EXCEPTION IS ALONG THE TN LINE...WHERE POPS
LINGER THRU THE OVERNIGHT. THE LATEST RAP 850 MB INITIALIZES THE 0C
LINE STILL BACK TO THE WEST. AND TEMPS IN THE MTNS ARE STILL IN THE
UPR 30S TO MID 40S. SO CHANGEOVER TO SNOW SHWRS HAS BEEN DELAYED.
LITTLE IF ANY ACCUMS ARE EXPECTED OVERNIGHT BEFORE SHWRS TAPER OFF
AROUND DAYBREAK TUESDAY.
AS OF 655 PM...NO SIGNIFICANT CHANGES TO THE PUBLIC FCST WITH THIS
UPDATE. TWEAKED TEMPS/DWPTS AGAIN WITH LATEST OBS. SKY/WIND/POP/WX
WERE ADJUSTED WITH LATEST GUIDANCE FOR THE 00Z TAFS. BASED ON RADAR
TRENDS...IT LOOKS LIKE THE THUNDER THREAT IS PRETTY MUCH OVER IN THE
UPPER SAVANNAH VALLEY.
AS OF 430 PM...THE POP TRENDS STILL LOOK ON TRACK. THERE ARE FEW
BREAKS IN THE CLOUDS ACRS GA AND WRN UPSTATE ON VIS SAT. CONVECTION
IS DEVELOPING WHERE THERE IS SOME INSOLATION...AND STILL MAY SEE AN
ISOLD TSTM OR TWO ACRS THE UPPER SAVANNAH VALLEY AND SRN UPSTATE
OVER THE NEXT COUPLE HOURS (LAPS CAPE IS UP TO 250 TO 600+ J/KG).
CANNOT RULE OUT SMALL HAIL/GRAUPEL WITH THE HEAVIEST
CONVECTION...GIVEN THE LOW FREEZING LEVELS...AND A FEW REPORTS IN
GA. I UPDATED THE TEMPS/DWPTS WITH THE LATEST OBS. TEMPS ARE RUNNING
COOLER THAN EXPECTED...GIVEN STUBBORN RAIN AND CLOUDS.
AS OF 210 PM EST...WATER VAPOR IMAGERY SHOWS A DIGGING UPPER LEVEL
SHORTWAVE OVER THE BASE OF THE SRN APPALACHIANS THIS
AFTERNOON...GRADUALLY ACQUIRING A MORE NEUTRAL TILT AS IT MOVES
EAST. DEEP LAYER DPVA AHEAD OF THIS WAVE IS CROSSING THE ERN HALF OF
THE FORECAST AREA THIS AFTN...WHILE ADDITIONAL SCT ACTIVITY DEVELOPS
BACK TO THE WEST UNDER THE COLD TROUGH ALOFT AND AHEAD OF THE
ASSOCIATED SFC COLD FRONT. A VERY FEW CLOUD TO CLOUD LIGHTNING
STRIKES WERE INDICATED EARLIER THIS AFTN...BUT THE CLOUD COVER HAS
KEPT LAPS SFC BASED CAPE VALUES LESS THAN 100 J/KG FOR ALL AREAS
EXCEPT THE EXTREME SRN PIEDMONT. WILL CONFINE ANY ISOLD THUNDER
MENTION GOING FORWARD TO SRN AND ERN SECTIONS THROUGH LATE AFTN.
SHEAR PROFILES REMAIN TOO WEAK FOR ANY SEVERE CONVECTION.
ANTICIPATE FROPA ACROSS THE MTNS THIS EVENING...BUT THEN THE
BOUNDARY WILL WASH OUT OVER THE PIEDMONT OR POSSIBLY GET HUNG UP
NEAR THE HIGHER TERRAIN OF THE SRN MTNS AND GRADUALLY DISSIPATE. THE
PASSING UPPER TROUGH WILL DEEPEN FURTHER TONIGHT...AND POSSIBLY CUT
OFF JUST EAST OF OUR FORECAST AREA...WITH STRONGER SFC WAVE
FORMATION LIKELY OUT OVER THE COASTAL PLAIN OVERNIGHT. THIS WILL
SLOW THE DEEP LAYER DRYING FROM THE WEST...AND LEAD TO A MORE
GRADUAL WEST TO EAST DROPOFF IN POPS. IN ADDITION...SUBFREEZING 850
MB TEMPS WILL ARRIVE ALONG THE SPINE OF THE SRN APPALACHIANS TOWARD
06Z. SCATTERED WESTERN MTNS SNOW SHOWERS OVERNIGHT COULD LEAD TO
VERY LIGHT ACCUMS IN THE TN BORDER COUNTIES...HOWEVER...THE LOW
LEVEL UPSLOPE FLOW WILL BE MORE NRLY THAN DESIRED FOR DECENT UPSLOPE
PRECIPITATION. CANNOT RULE OUT SOME LIGHT ICING GIVEN THE SHALLOW
MOISTURE PROFILES AND POSSIBLE LINGERING WARM NOSE...BUT RAIN/SNOW
IS PREFERRED BY THE CONSENSUS PROFILES.
FINALLY...WEAK DEFORMATION ZONE FORCING W OF THE COASTAL LOW...ALONG
WITH LINGERING 850 MB MOISTURE IN THE NRLY FLOW...WILL LIKELY ALLOW
CLOUDS TO PERSIST OVER THE WRN CAROLINAS THROUGH MUCH OF TUESDAY.
HOWEVER...NO FURTHER SHOWERS ARE EXPECTED THIS FAR W. TEMPERATURES
WILL BE NEAR CLIMATOLOGY...EXCEPT COOLER THAN CLIMO IN WRN NC.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
AS OF 145 PM MONDAY...TUESDAY NIGHT AND WED SHOULD BE QUIET ACROSS
THE WESTERN CAROLINAS AND NE GA AS SHORT WAVE RIDGING DEVLOPS ACROSS
THE AREA. HOWEVER...THE FLOW WILL QUICKLY AMPLIFY ON THURSDAY AS A
SHARP UPPER TROUGH QUICKLY DIGS SE OUT OF CANADA WITH A LONG WAVE
TROUGH DEVELOPING OVER THE EASTERN U.S. ON THURSDAY. THE DIGGING
UPPER TROUGH WILL SPAWN A CLIPPER LOW WHICH IS FORECAST TO MOVE WELL
NORTH OF THE AREA...BUT IS ASSOCIATED COLD FRONT WILL MOVE ACROSS
THE FORECAST AREA ON THURSDAY. THE FRONT WILL BE MOISTURE STARVED SO
DESPITE THE RATHER IMPRESSIVE UPPER AIR DYNAMICS...LITTLE IN THE WAY
OF PRECIP WILL ACCOMPANY THE FRONT OUTSIDE THE MOUNTAINS EXCEPT
PERHAPS SOME SPRINKLES/FLURRIES WITH THE PASSAGE OF THE UPPER TROUGH
THU AFTERNOON. HOWEVER...THE DEVELOPING NW FLOW WILL SQEEZE OUT SOME
MAINLY UPSLOPE INDUCED SNOW SHOWERS IN THE MOUTNAINS ON THU...BUT
RIGHT NOW ACCUMULATIONS LOOK TO BE ON THE LIGHT SIDE EVEN THOUGH
FORECAST SOUNDINGS LOOK SOMEWHAT CONVECTIVE. THEREFORE...WOULD NOT
BE SURPRISED IF ADVISORY LEVEL SNOW ACCUMS RESULT BY LATE THU
ESPECIALLY IN THE NORTHERN MOUNTAINS. THE BIG STORY WILL BE THE
PLUNGING TEMPS. MAX TEMPS IN THE MOUNTAINS ON THURSDAY WILL OCCUR IN
THE EARLY MORNING THEN FALLING THROUGHOUT THE DAY AS 850 TEMPS FALL
WELL INTO THE NEGATIVE TEENS. OUTSIDE THE MOUNTAINS AS
USUAL...DOWNSLOPE FLOW WILL MITIGATE COLD ADVECTION INITIALLY BUT
WILL EVENTUALLY BE OVERWHELMED BY CAA IN THE AFTERNOON. MAX TEMPS
OUTSIDE THE MOUNTAINS LOOK TO OCCUR IN THE EARLY AFTEERNOON AND THEN
FALL OFF AS 850 TEMPS FALL INTO THE NEGATIVE LOWER TEENS BY 00Z FRI.
WINDS WILL ALSO INCREASE AND BECOME GUSTY ON THURSDAY BUT LOOK TO
REMAIN BELOW ADVISORY LEVELS AT THIS POINT. MAX TEMPS SHOULD BE NEAR
CLIMO ON WED AND THEN WELL BELOW CLIMO IN THE MOUNTAINS THU AND
ABOUT A CATEGORY BELOW EAST OF THE MOUNTAINS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 210 PM MONDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON FRIDAY
WITH A HIGHLY AMPLIFIED UPPER TROF AXIS RIGHT OVER THE CAROLINAS AND
STEEP UPPER RIDGING OVER THE WESTERN CONUS. OVER THE NEXT 24
HRS...THE TROF AXIS LIFTS TO THE NE HOWEVER WE WILL LIKELY REMAIN
UNDER BROAD UPPER TROFFING THRU MOST OF THE PERIOD. ON SAT...THE
TROF AMPLIFIES AGAIN AND BRINGS ANOTHER ROUND OF IMPRESSIVE PVA AND
COLD AIR OVER THE REGION. BY EARLY MON...THIS ENERGY LIFTS NE AND
HEIGHTS RISE AS THE UPPER PATTERN FLATTENS OUT. IT SHOULD BE NOTED
THAT THE OVERALL MODEL AGREEMENT FOR THE PERIOD LOOKS ESPECIALLY
GOOD.
AT THE SFC...SIGNIFICANT CAA WILL BE UNDERWAY BY LATE THURS/EARLY
FRI AS COLD CANADIAN HIGH PRESSURE PUSHES INTO THE REGION FROM THE
NW. OVER THE NEXT 24 HRS...A LOW IS EXPECTED TO DEVELOP OVER THE
GREAT LAKES AND DRIFT SE...YET ITS LOOKING LIKE MOST OF THE DEEPER
MOISTURE ASSOCIATED WITH THAT SYSTEM WILL REMAIN TO OUR NORTH. AS
THE LOW TRACKS EASTWARD...ANOTHER STRONG CANADIAN HIGH MOVES INTO
THE REGION ON SUNDAY BRINGING SOME OF THE COLDEST/DRIEST AIR OF THE
SEASON. THE HIGH IS EXPECTED TO REMAIN OVER THE AREA THRU NEW DAY 7
WHICH IS NEXT MONDAY. THE ONLY POPS I CARRY FOR THE PERIOD ARE SMALL
AREAS OF SLIGHT CHANCE OVER THE NORTHERN MTS LATE THURS/EARLY FRI
AND SAT. OTHERWISE...IT WILL BE DRY. MORE NOTEWORTHY WILL BE WELL
BELOW NORMAL TEMPS ON FRI AND SUN WITH EQUALLY DRY DEWPTS. THESE
TEMPS COUPLED WITH GUSTY WINDS COULD CAUSE SOME FIRE DANGER ISSUES
AND WIND CHILL CONCERNS EARLY FRIDAY AND SUNDAY...ESPECIALLY OVER
THE HIGHER ELEVATIONS.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
AT KCLT...SPOTTY SHOWERS CONTINUE TO SLOWLY WORK THRU THE AREA FROM
THE WEST. THERE WILL CONTINUE TO BE LINGERING LLVL MOISTURE FROM THE
RAIN...UNTIL A SFC FRONT CAN PUSH THRU THE AREA FROM THE NW...AND
THE PRES GRAD INCREASES ACRS THE AREA OVERNIGHT. THIS SHUD ALLOW BL
WINDS TO INCREASE TO AROUND 8-10 KTS OUT OF THE NE...AND ALLOW FOG
TO DISSIPATE AND CIGS TO LIFT TO AT LEAST LOW MVFR. GUIDANCE SEEMS
TO BE TRENDING SLOWER ON DRYING OUT THE LLVLS TO GET RID OF THE MVFR
DECK UNTIL LATE TUESDAY MORNING. FROM MIDDAY THRU THE AFTN...EXPECT
VFR CLOUDS TO LINGER...AND NE WINDS BECOMING GUSTY INTO THE 20-22 KT
RANGE.
ELSEWHERE...SHOWERS CONTINUE TO LINGER ACRS THE AREA...BUT SHUD
DISSIPATE BY AROUND MIDNIGHT (EXCEPT A FEW NW FLOW SHWRS ALONG THE
TN BORDER OVERNIGHT). A SFC FRONT IS SLOW TO PUSH THRU THE
AREA...AND LINGERING MOISTURE FROM TODAY/S RAIN WILL KEEP PATCHY FOG
AND LOW STRATUS THRU THE EVENING HOURS. GUIDANCE IS MIXED ON HOW
MUCH FOG/STRATUS WILL CONTINUE OVERNIGHT THRU TUESDAY MORNING. I
STILL THINK ONCE LOW PRES ORGANIZED TO THE EAST AND THE SFC FRONT
GETS ALL THE WAY THRU THE AREA...LLVL FLOW SHUD INCREASE OUT OF THE
NE AND SCOUR OUT A LOT OF THE FOG/CLOUDS. STILL...AN MVFR CIG MAY
LINGER ACRS MOST OF THE AREA THRU DAYBREAK TUESDAY...BUT CONFIDENCE
IS ONLY AROUND 50-60%...GIVEN STARK MODEL DISAGREEMENT. DEFINITELY
EXPECT VFR CONDITIONS AT ALL SITES BY MIDDAY TUESDAY...WITH
MARGINALLY GUSTY N/NE WINDS THRU THE AFTN.
OUTLOOK...DRYING CONDITIONS ARE EXPECTED LATE TUE THROUGH WED. A
COLD FRONT WILL CROSS THE REGION FROM THE NW ON THU...BUT WITH
LIMITED MOISTURE. BREEZY TO WINDY CONDITIONS ARE EXPECTED BEHIND THE
FRONT THU THROUGH FRI...WITH COLDER TEMPERATURES.
CONFIDENCE TABLE...
01-07Z 07-13Z 13-19Z 19-00Z
KCLT HIGH 80% HIGH 100% HIGH 82% HIGH 100%
KGSP LOW 50% LOW 50% HIGH 88% HIGH 100%
KAVL MED 78% LOW 52% MED 77% HIGH 100%
KHKY MED 67% MED 62% MED 72% HIGH 100%
KGMU LOW 53% LOW 53% HIGH 89% HIGH 100%
KAND MED 60% LOW 46% MED 67% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...CSH
NEAR TERM...ARK/HG
SHORT TERM...LG
LONG TERM...JPT
AVIATION...ARK
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
903 PM CST MON FEB 9 2015
.UPDATE...
ISSUED AT 848 PM CST MON FEB 9 2015
HAVE UPDATED THE FORECAST TONIGHT TO ADD A DENSE FOG ADVISORY FOR
SOUTH CENTRAL SOUTH DAKOTA. CURRENT WEB CAMS IN KIMBALL LOOK
FAIRLY DAUNTING...AND CHAMBERLAIN WEB CAMS SHOW STRATUS HANGING
JUST ABOVE THE GROUND. HRRR AND RAP BOTH SHOW DENSE FOG DEVELOPING ACROSS
CENTRAL SOUTH DAKOTA THIS EVENING. QUESTIONS REMAIN AS TO HOW LONG
THE DENSE FOG WILL STICK AROUND. STRONG AND DEEP WARM AIR
ADVECTION ACROSS SOUTH CENTRAL SOUTH DAKOTA MAY ALLOW FOR STEADY
IF NOT RISING TEMPERATURES TONIGHT ACROSS CENTRAL SOUTH DAKOTA.
WITH STRONG WARM AIR ADVECTION...EXPECT SOME SHOWERS TO DEVELOP
TOWARDS THE 06Z TIME FRAME ACROSS CENTRAL SOUTH DAKOTA THROUGH THE
OVERNIGHT. THE SHOWERS MAY NOT BE SO PROBLEMATIC ACROSS CENTRAL
SOUTH DAKOTA AS LONG AS TEMPERATURES AT THE SURFACE REMAIN ABOVE
FREEZING...BUT SHOWERS ARE EXPECTED TO SHIFT EAST INTO THE COLDER
AIR CREATING A SET UP FOR FREEZING RAIN AND SLEET. FOR NOW...THE
AREAL COVERAGE LOOKS GOOD FOR FREEZING RAIN...BUT LOWERED ICING
POTENTIAL ACROSS THE WEST WITH WARMER TEMPERATURES.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 335 PM CST MON FEB 9 2015
MAIN FOCUS IN THE SHORT TERM WILL BE A POTENT UPPER LEVEL TROUGH
TRACKING EAST ACROSS THE NORTHERN PLAINS. THE LOW STRATUS WILL
LINGER THIS EVENING AS LIGHT SOUTHEAST WINDS INCREASE AHEAD OF THE
WAVE. LIGHT PRECIPITATION WILL BEGIN SPREADING INTO THE WESTERN
FORECAST AREA LATER THIS EVENING AS MID AND HIGH CLOUDS ARRIVE WITH
THE WAVE. PRECIPITATION WILL GRADUALLY SPREAD EAST
OVERNIGHT...REACHING THE INTERSTATE 29 CORRIDOR IN THE EARLY MORNING
HOURS AND OUR FAR EASTERN FORECAST AREA LATE TONIGHT. THE LOW CLOUDS
WILL PERSIST...BUT THE MAIN CONCERN WILL BE THE RATHER SIGNIFICANT
DRY LEVELS FROM 750 TO 850 MB BETWEEN THE CLOUD LAYERS. WE DO SEE
SOME WEAK LIFT IN BOTH LAYERS...WHICH COULD SPELL MORE FREEZING
DRIZZLE TYPE PRECIPITATION...BUT ALSO THINK THAT SOME IMPACT FROM
THE MID CLOUDS WILL POINT TO AT LEAST SOME POTENTIAL FOR LIGHT
MEASURABLE PRECIPITATION. WITH THE MODELS TAKING THE BEST FORCING
AND SUPPORT JUST TO OUR NORTH...OUR BEST POTENTIAL WILL BE NORTH OF
INTERSTATE 90. PRECIPITATION TAPERS OFF TUESDAY MORNING FROM WEST TO
EAST AND SHOULD BE LARGELY DONE BY MIDDAY.
FORECAST SOUNDINGS SHOW THAT THE MAIN PRECIPITATION WILL BE RAIN.
WITH THE VAST MAJORITY OF THE FORECAST AREA EXPECTED TO BE AT OR
BELOW FREEZING...FREEZING RAIN SHOULD BE THE MAIN TYPE. A LITTLE
ELEVATED INSTABILITY DOES TRACK ACROSS OUR NORTHERN HALF...WHICH MAY
ALLOW MORE OF A SHOWERY ELEMENT LATE TONIGHT. SLEET WILL ALSO BE A
POSSIBILITY MAINLY EAST CENTRAL SD INTO SOUTHWEST MINNESOTA. THERE
REMAINS SOME UNCERTAINTY ON THE IMPACT OF SOME LIGHT ICING WITH THE
FREEZING RAIN BUT IT DOES NOT TAKE MUCH ICE TO CREATE SLIPPERY
SURFACES AND UNTREATED ROADWAYS. DECIDED TO GO WITH A FREEZING RAIN
ADVISORY LATE TONIGHT THROUGH TUESDAY MORNING FOR THE HIGHWAY 14
CORRIDOR INTO THE SIOUX FALLS AREA WHERE THE BEST POTENTIAL FOR SOME
LIGHT ICE ACCUMULATION IS POSSIBLE - YET EVEN HERE AM ONLY EXPECTING
LESS THAN 0.05 INCHES. DEBATED LEAVING THE FSD AREA OUT OF THE
ADVISORY...BUT GIVEN THE TIMING OF THE ICE POTENTIAL WILL BE AROUND
THE MORNING COMMUTE FELT THAT THE ADVISORY WOULD GIVE THE PROPER
HEADS UP FOR A POSSIBLE SLICK COMMUTE. WE WILL HAVE TO SEE IF AND
HOW THE CONVECTIVE ELEMENT PLAYS OUT...WHICH MAY REQUIRE ADJUSTING
THE ADVISORY ZONES.
CLOUDS START CLEARING IN SOUTH CENTRAL SD IN THE AFTERNOON BUT
LINGER THROUGH THE DAY ELSEWHERE. BUT THE BREEZY SOUTHERLY WINDS
TURNING NORTHWESTERLY BEHIND THE FRONT SHOULD ALLOW SOME DECENT
WARMING REGARDLESS. HIGHS WILL BE MILDER IN THE UPPER 30S TO MID
50S...SO ANY SLICK SPOTS ON ROADWAYS SHOULD MELT IN THE AFTERNOON.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 335 PM CST MON FEB 9 2015
A STRONG COLD FRONT WILL BLAST THROUGH THE AREA ON TUESDAY NIGHT.
WITH THE COLD AIR ADVECTION AND A STEEPENING GRADIENT IT WILL BECOME
INCREASINGLY WINDY DURING THE NIGHT. A SECONDARY SHORTWAVE WILL DROP
SOUTHWARD ON A NORTHWESTERLY UPPER LEVEL FLOW OVERNIGHT...AND WITH
A SATURATED DENDRITIC LAYER KEPT WITH SCATTERED FLURRIES IN PORTIONS
OF OUR NORTH AND EAST LATER IN THE NIGHT. WITH THE COLD AIR
ADVECTION LOWS WILLS DROP DOWN INTO THE MID TEENS TO LOWER 20S.
HIGH PRESSURE BUILDS INTO THE NORTHERN PLAINS ON WEDNESDAY AND
WEDNESDAY NIGHT. IT WILL REMAIN BREEZY THROUGH THE DAY HOWEVER WITH
GOOD MIXING...AND WINDS WILL ONLY SLOWLY FALL OFF ON WEDNESDAY
NIGHT. WITH THERMAL PROFILES CONTINUING TO COOL...HIGHS ON WEDNESDAY
WILL ONLY BE IN THE TEENS NORTHEAST TO NEAR 30 ALONG THE MO RIVER
CORRIDOR...DROPPING OFF TO JUST EITHER SIDE OF ZERO ON WEDNESDAY
NIGHT.
THE RIDGE AXIS SLIDES ACROSS THE REGION ON THURSDAY...WITH THE BRUNT
OF THE COLDER AIR SITTING OVER THE AREA HIGHS WILL ONLY MAKE IT INTO
THE TEENS TO MID 20S. AS THE HIGH MOVES OFF TO THE EAST...A
SOUTHERLY FLOW RETURNS TO THE REGION ON THURSDAY NIGHT...AND
OVERNIGHT LOWS WILL BE VERY SIMILAR TO THURSDAYS HIGHS...REMAINING
NEARLY STEADY IN THE TEENS AND LOWER 20S. MODELS IN DECENT AGREEMENT
ON A COLD FRONTAL PASSAGE ON FRIDAY MORNING...BUT WITH GOOD MIXING
BEHIND THE FRONT IT WILL REMAIN MILD WITH HIGHS ON FRIDAY BACK ABOVE
NORMAL...IN THE UPPER 20S TO LOWER 40S.
THE ROLLERCOASTER RIDE IN TEMPERATURES CONTINUES INTO THE EXTENDED
WITH VARIOUS WAVES PASSING TO OUR EAST IN A NORTHWESTERLY UPPER
LEVEL FLOW. AFTER A COOL DOWN ON SATURDAY...TEMPERATURES LOOK TO
REBOUND FOR THE BEGINNING OF NEXT WEEK. IT APPEARS TO BE DRY THROUGH
MOST OF THE EXTENDED...BEFORE INDICATIONS OF POSSIBLE PRECIPITATION
ON MONDAY AS ANOTHER SHORTWAVE SLIDES INTO THE REGION.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 535 PM CST MON FEB 9 2015
LOW STRATUS AND AREAS OF FOG TO CONTINUE THROUGH THE FORECAST
PERIOD. WAVE MOVING THROUGH THE AREA WILL PRODUCE LIGHT FREEZING
RAIN AT KHON...WITH LESSER AMOUNTS TO THE SOUTH. ONLY HAVE A FEW
HOURS OF FREEZING RAIN AT KFSD...AND NOTHING AT KSUX TERMINAL.
NORTHWEST WINDS WILL INCREASE FROM NORTHWEST TO SOUTHEAST TOMORROW
AFTERNOON FLUSHING LOW LEVEL MOISTURE AND IMPROVING CEILINGS AND
VISIBILITY. MOIST SOUTHEAST FLOW WILL REMAIN STRONG AHEAD OF
BOUNDARY.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...DENSE FOG ADVISORY UNTIL 9 AM CST TUESDAY FOR SDZ050-052-057>059-
063-064-068.
FREEZING RAIN ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST TUESDAY
FOR SDZ038>040-052>056-061-062.
MN...FREEZING RAIN ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST TUESDAY
FOR MNZ071-072-097-098.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...
SHORT TERM...
LONG TERM...JM
AVIATION...
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
137 PM CST SUN FEB 8 2015
.UPDATE...
TO LOWER SOME HIGH TEMPERATURES.
&&
.DISCUSSION...
CLOUDS HAVE FINALLY BURNED OFF...BUT TEMPERATURES ARE WELL BELOW
THE FORECAST FROM SAN ANTONIO TO THE WEST. HAVE ADJUSTED HIGHS
DOWN ACROSS THIS AREA.
&&
.PREV DISCUSSION... /ISSUED 1148 AM CST SUN FEB 8 2015/
AVIATION...
PESKY IFR CIGS AND MVFR VSBY SHOULD CLEAR OUT TO SKC BETWEEN 18
AND 20Z AT ALL SITES. A COLD FRONT WILL ARRIVE SHORTLY AFTER 19Z AT
KDRT AND BY 00Z AT THE I-35 SITES...BRINGING NORTHERLY WINDS THAT
WILL CONTINUE THROUGH THE OVERNIGHT PERIOD AND THROUGH THE DAY ON
MONDAY. SOME MODEL GUIDANCE IS CONFUSED BY INDICATING FAIRLY DENSE
GROUND FOG IN THE MORNING. BUT WITH TEMPERATURE-DEW POINT SPREADS
OF 5-10 DEGREES AND STEADY NORTHERLY WINDS OVERNIGHT...FOG SHOULD
ALSO NOT OCCUR. THUS HAVE LEFT IT OUT...BUT PILOTS CAN EXPECT
MODERATE TO HEAVY DEW MONDAY MORNING ON AIRCRAFT LEFT OUTDOORS.
PREV DISCUSSION... /ISSUED 1026 AM CST SUN FEB 8 2015/
UPDATE...
TO EXPIRE THE DENSE FOG ADVISORY.
DISCUSSION...
VISIBILITY HAS IMPROVED ACROSS THE CWA AND IS GENERALLY BETWEEN
ONE AND FIVE MILES WHERE THERE IS STILL FOG. THERE ARE STILL A FEW
SPOTS ALONG THE RIO GRANDE WHERE VISIBILITY IS BELOW HALF A MILE.
EXPECTING THE FOG TO DISSIPATE COMPLETELY BY NOON. HAVE ALLOWED
THE DENSE FOG ADVISORY TO EXPIRE. HAVE ALSO ADJUSTED GRIDS TO
ACCOUNT FOR OBSERVATIONAL TRENDS. OTHERWISE THE FORECAST IS IN
GOOD SHAPE.
PREV DISCUSSION... /ISSUED 604 AM CST SUN FEB 8 2015/
UPDATE...SECOND UPDATE TO EXPAND DENSE FOG ADVISORY INTO VAL
VERDE COUNTIES AS WELL AS COUNTIES SURROUNDING BEXAR
COUNTY...BASED ON ASOS AND WEB CAM TRENDS.
PREV DISCUSSION... /ISSUED 551 AM CST SUN FEB 8 2015/
UPDATE...TRENDS FROM AREA WEBCAMS AND AUTOMATED SURFACE SITES
INDICATE DENSE FOG IS BECOMING WIDESPREAD ENOUGH TO WARRANT A
DENSE FOG ADVISORY ACROSS THE SOUTHWEST CWA. THE DENSE FOG
ADVISORY IS ALONG A BEXAR COUNTY TO KINNEY COUNTY LINE...
SOUTHWARD...CLOSE TO WHERE HRRR IS INDICATING IT SHOULD BE.
VISIBILITIES SHOULD GRADUALLY IMPROVE 9 AM TO 10 AM.
PREV DISCUSSION... /ISSUED 513 AM CST SUN FEB 8 2015/
AVIATION...
STRATUS WITH IFR/LIFR CIGS AND BR/FG WITH VSBYS AS LOW AS VLIFR
WILL LINGER INTO MID MORNING AND THEN ERODE FROM WEST TO EAST LATE
MORNING INTO EARLY AFTERNOON BY AROUND 19Z. VFR SKIES WILL PREVAIL
FOR THE REST OF TODAY THROUGH MONDAY MORNING AS A DRIER AIRMASS
FILTERS INTO OUR AREA IN THE WAKE OF A SURFACE TROUGH/COLD FRONT.
ALTHOUGH SOME MODELS SHOW SHALLOW MOISTURE AND A POTENTIAL FOR
BR/FG AND STRATUS WITH LIFR/VLIFR CIGS/VSBYS LATE TONIGHT INTO
MONDAY MORNING...WILL LEAVE MENTION OUT AS A DRIER AIRMASS SHOULD
WIN OUT. SWLY WINDS 7 TO 14 KTS WILL TURN NWLY TO NLY AS SURFACE
TROUGH/COLD FRONT MOVES ACROSS THIS AFTERNOON INTO EVENING. SOME
GUSTS UP TO 25 KTS ARE POSSIBLE THIS AFTERNOON.
PREV DISCUSSION... /ISSUED 343 AM CST SUN FEB 8 2015/
SHORT TERM (TODAY THROUGH MONDAY)...LOW STRATUS DECK HAS DEVELOPED
ALONG THE EDGE OF THE ESCARPMENT EARLY THIS MORNING WITH AREAS OF
FOG AND A MIX OF STRATUS ACROSS THE COASTAL PLAINS. HRRR HAS A
DECENT HANDLE ON THE STRATUS THIS MORNING. STRATUS WILL GRADUALLY
SCATTER OUT 10 AM TO 1 PM AS MIXING INCREASES. DRY SOUTHWEST WINDS
TODAY WILL PROMOTE WARM TEMPS...WITH HIGHS IN THE UPPER 70S TO LOW
80S MOST AREAS. SURFACE TROUGH/FRONT MOVES THROUGH THE HILL COUNTRY
AND RIO GRANDE PLAINS MID AFTERNOON...WITH DRY/WARM/BREEZY NORTHWEST
WIND DEVELOPING BEHIND IT. THE TROUGH MOVES EAST OF THE I-35 CORRIDOR
EARLY THIS EVENING. ANY PRECIP SHOULD REMAIN EAST OF THE CWA.
SLIGHTLY COOLER AND DRY ON MONDAY.
LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...DRY CONDITIONS
CONTINUE TUESDAY AS WEAK MID AND UPPER LEVEL RIDGING PASSES
THROUGH THE AREA MONDAY INTO TUESDAY. THE RIDGE FLATTENS AND
SHIFTS EAST TUESDAY NIGHT WITH A SHALLOW MOISTURE RETURN TAKING
PLACE ACROSS SOUTH-CENTRAL TEXAS. AN UPPER LEVEL TROUGH MOVES OUT
OF THE PLAINS WEDNESDAY AND INTO EASTERN CONUS THURSDAY. THIS
SENDS A COLD FRONT THROUGH THE CWA LATE WEDNESDAY OR EARLY
THURSDAY...STILL TIMING DIFFERENCES BETWEEN MODELS. A WEAK UPPER
LEVEL LOW PINCHES OFF FROM THE WESTERN END OF THE TROUGH AXIS OVER
THE SOUTHERN ROCKIES WEDNESDAY...THEN RETROGRADES TO THE SOUTHWEST
ACROSS NORTHWEST MEXICO THU-FRI...BENEATH AMPLIFYING WEST COAST
RIDGE. WITH MOISTURE RETURN AHEAD OF THE FRONT SHALLOW AND DEEPER
FORCING PASSING EAST OF THE AREA WITH THE MAIN TROUGH AXIS AND
WELL WEST WITH THE CUT OFF LOW...POPS ALONG AND BEHIND THE FRONT
WILL REMAIN LOW...LIMITED TO 20-30S MAINLY WEST OF I-35. COOLER
HIGHS THU AND FRI...IN THE MID 50S TO MID 60S.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 51 77 49 75 50 / 0 0 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 48 76 44 74 47 / 0 0 0 0 0
NEW BRAUNFELS MUNI AIRPORT 51 76 47 75 49 / 0 0 0 0 0
BURNET MUNI AIRPORT 48 75 46 74 48 / 0 0 0 0 0
DEL RIO INTL AIRPORT 48 78 48 76 50 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 48 76 46 74 49 / 0 0 0 0 0
HONDO MUNI AIRPORT 49 79 45 76 48 / 0 0 0 0 0
SAN MARCOS MUNI AIRPORT 50 76 46 74 49 / 0 0 0 0 0
LA GRANGE - FAYETTE REGIONAL 52 76 47 74 49 / - 0 0 0 0
SAN ANTONIO INTL AIRPORT 51 77 48 75 50 / 0 0 0 0 0
STINSON MUNI AIRPORT 51 77 47 76 49 / 0 0 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...ZEITLER
SYNOPTIC/GRIDS...FOGARTY
PUBLIC SERVICE/DATA COLLECTION...TREADWAY
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1148 AM CST SUN FEB 8 2015
.AVIATION...
PESKY IFR CIGS AND MVFR VSBY SHOULD CLEAR OUT TO SKC BETWEEN 18
AND 20Z AT ALL SITES. A COLD FRONT WILL ARRIVE SHORTLY AFTER 19Z AT
KDRT AND BY 00Z AT THE I-35 SITES...BRINGING NORTHERLY WINDS THAT
WILL CONTINUE THROUGH THE OVERNIGHT PERIOD AND THROUGH THE DAY ON
MONDAY. SOME MODEL GUIDANCE IS CONFUSED BY INDICATING FAIRLY DENSE
GROUND FOG IN THE MORNING. BUT WITH TEMPERATURE-DEW POINT SPREADS
OF 5-10 DEGREES AND STEADY NORTHERLY WINDS OVERNIGHT...FOG SHOULD
ALSO NOT OCCUR. THUS HAVE LEFT IT OUT...BUT PILOTS CAN EXPECT
MODERATE TO HEAVY DEW MONDAY MORNING ON AIRCRAFT LEFT OUTDOORS.
&&
.PREV DISCUSSION... /ISSUED 1026 AM CST SUN FEB 8 2015/
UPDATE...
TO EXPIRE THE DENSE FOG ADVISORY.
DISCUSSION...
VISIBILITY HAS IMPROVED ACROSS THE CWA AND IS GENERALLY BETWEEN
ONE AND FIVE MILES WHERE THERE IS STILL FOG. THERE ARE STILL A FEW
SPOTS ALONG THE RIO GRANDE WHERE VISIBILITY IS BELOW HALF A MILE.
EXPECTING THE FOG TO DISSIPATE COMPLETELY BY NOON. HAVE ALLOWED
THE DENSE FOG ADVISORY TO EXPIRE. HAVE ALSO ADJUSTED GRIDS TO
ACCOUNT FOR OBSERVATIONAL TRENDS. OTHERWISE THE FORECAST IS IN
GOOD SHAPE.
PREV DISCUSSION... /ISSUED 604 AM CST SUN FEB 8 2015/
UPDATE...SECOND UPDATE TO EXPAND DENSE FOG ADVISORY INTO VAL
VERDE COUNTIES AS WELL AS COUNTIES SURROUNDING BEXAR
COUNTY...BASED ON ASOS AND WEB CAM TRENDS.
PREV DISCUSSION... /ISSUED 551 AM CST SUN FEB 8 2015/
UPDATE...TRENDS FROM AREA WEBCAMS AND AUTOMATED SURFACE SITES
INDICATE DENSE FOG IS BECOMING WIDESPREAD ENOUGH TO WARRANT A
DENSE FOG ADVISORY ACROSS THE SOUTHWEST CWA. THE DENSE FOG
ADVISORY IS ALONG A BEXAR COUNTY TO KINNEY COUNTY LINE...
SOUTHWARD...CLOSE TO WHERE HRRR IS INDICATING IT SHOULD BE.
VISIBILITIES SHOULD GRADUALLY IMPROVE 9 AM TO 10 AM.
PREV DISCUSSION... /ISSUED 513 AM CST SUN FEB 8 2015/
AVIATION...
STRATUS WITH IFR/LIFR CIGS AND BR/FG WITH VSBYS AS LOW AS VLIFR
WILL LINGER INTO MID MORNING AND THEN ERODE FROM WEST TO EAST LATE
MORNING INTO EARLY AFTERNOON BY AROUND 19Z. VFR SKIES WILL PREVAIL
FOR THE REST OF TODAY THROUGH MONDAY MORNING AS A DRIER AIRMASS
FILTERS INTO OUR AREA IN THE WAKE OF A SURFACE TROUGH/COLD FRONT.
ALTHOUGH SOME MODELS SHOW SHALLOW MOISTURE AND A POTENTIAL FOR
BR/FG AND STRATUS WITH LIFR/VLIFR CIGS/VSBYS LATE TONIGHT INTO
MONDAY MORNING...WILL LEAVE MENTION OUT AS A DRIER AIRMASS SHOULD
WIN OUT. SWLY WINDS 7 TO 14 KTS WILL TURN NWLY TO NLY AS SURFACE
TROUGH/COLD FRONT MOVES ACROSS THIS AFTERNOON INTO EVENING. SOME
GUSTS UP TO 25 KTS ARE POSSIBLE THIS AFTERNOON.
PREV DISCUSSION... /ISSUED 343 AM CST SUN FEB 8 2015/
SHORT TERM (TODAY THROUGH MONDAY)...LOW STRATUS DECK HAS DEVELOPED
ALONG THE EDGE OF THE ESCARPMENT EARLY THIS MORNING WITH AREAS OF
FOG AND A MIX OF STRATUS ACROSS THE COASTAL PLAINS. HRRR HAS A
DECENT HANDLE ON THE STRATUS THIS MORNING. STRATUS WILL GRADUALLY
SCATTER OUT 10 AM TO 1 PM AS MIXING INCREASES. DRY SOUTHWEST WINDS
TODAY WILL PROMOTE WARM TEMPS...WITH HIGHS IN THE UPPER 70S TO LOW
80S MOST AREAS. SURFACE TROUGH/FRONT MOVES THROUGH THE HILL COUNTRY
AND RIO GRANDE PLAINS MID AFTERNOON...WITH DRY/WARM/BREEZY NORTHWEST
WIND DEVELOPING BEHIND IT. THE TROUGH MOVES EAST OF THE I-35 CORRIDOR
EARLY THIS EVENING. ANY PRECIP SHOULD REMAIN EAST OF THE CWA.
SLIGHTLY COOLER AND DRY ON MONDAY.
LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...DRY CONDITIONS
CONTINUE TUESDAY AS WEAK MID AND UPPER LEVEL RIDGING PASSES
THROUGH THE AREA MONDAY INTO TUESDAY. THE RIDGE FLATTENS AND
SHIFTS EAST TUESDAY NIGHT WITH A SHALLOW MOISTURE RETURN TAKING
PLACE ACROSS SOUTH-CENTRAL TEXAS. AN UPPER LEVEL TROUGH MOVES OUT
OF THE PLAINS WEDNESDAY AND INTO EASTERN CONUS THURSDAY. THIS
SENDS A COLD FRONT THROUGH THE CWA LATE WEDNESDAY OR EARLY
THURSDAY...STILL TIMING DIFFERENCES BETWEEN MODELS. A WEAK UPPER
LEVEL LOW PINCHES OFF FROM THE WESTERN END OF THE TROUGH AXIS OVER
THE SOUTHERN ROCKIES WEDNESDAY...THEN RETROGRADES TO THE SOUTHWEST
ACROSS NORTHWEST MEXICO THU-FRI...BENEATH AMPLIFYING WEST COAST
RIDGE. WITH MOISTURE RETURN AHEAD OF THE FRONT SHALLOW AND DEEPER
FORCING PASSING EAST OF THE AREA WITH THE MAIN TROUGH AXIS AND
WELL WEST WITH THE CUT OFF LOW...POPS ALONG AND BEHIND THE FRONT
WILL REMAIN LOW...LIMITED TO 20-30S MAINLY WEST OF I-35. COOLER
HIGHS THU AND FRI...IN THE MID 50S TO MID 60S.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 51 77 49 75 50 / 0 0 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 48 76 44 74 47 / 0 0 0 0 0
NEW BRAUNFELS MUNI AIRPORT 51 76 47 75 49 / 0 0 0 0 0
BURNET MUNI AIRPORT 48 75 46 74 48 / 0 0 0 0 0
DEL RIO INTL AIRPORT 48 78 48 76 50 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 48 76 46 74 49 / 0 0 0 0 0
HONDO MUNI AIRPORT 49 79 45 76 48 / 0 0 0 0 0
SAN MARCOS MUNI AIRPORT 50 76 46 74 49 / 0 0 0 0 0
LA GRANGE - FAYETTE REGIONAL 52 76 47 74 49 / - 0 0 0 0
SAN ANTONIO INTL AIRPORT 51 77 48 75 50 / 0 0 0 0 0
STINSON MUNI AIRPORT 51 77 47 76 49 / 0 0 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...26
SYNOPTIC/GRIDS...05
PUBLIC SERVICE/DATA COLLECTION...12
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1026 AM CST SUN FEB 8 2015
.UPDATE...
TO EXPIRE THE DENSE FOG ADVISORY.
&&
.DISCUSSION...
VISIBILITY HAS IMPROVED ACROSS THE CWA AND IS GENERALLY BETWEEN
ONE AND FIVE MILES WHERE THERE IS STILL FOG. THERE ARE STILL A FEW
SPOTS ALONG THE RIO GRANDE WHERE VISIBILITY IS BELOW HALF A MILE.
EXPECTING THE FOG TO DISSIPATE COMPLETELY BY NOON. HAVE ALLOWED
THE DENSE FOG ADVISORY TO EXPIRE. HAVE ALSO ADJUSTED GRIDS TO
ACCOUNT FOR OBSERVATIONAL TRENDS. OTHERWISE THE FORECAST IS IN
GOOD SHAPE.
&&
.PREV DISCUSSION... /ISSUED 604 AM CST SUN FEB 8 2015/
UPDATE...SECOND UPDATE TO EXPAND DENSE FOG ADVISORY INTO VAL
VERDE COUNTIES AS WELL AS COUNTIES SURROUNDING BEXAR
COUNTY...BASED ON ASOS AND WEB CAM TRENDS.
PREV DISCUSSION... /ISSUED 551 AM CST SUN FEB 8 2015/
UPDATE...TRENDS FROM AREA WEBCAMS AND AUTOMATED SURFACE SITES
INDICATE DENSE FOG IS BECOMING WIDESPREAD ENOUGH TO WARRANT A
DENSE FOG ADVISORY ACROSS THE SOUTHWEST CWA. THE DENSE FOG
ADVISORY IS ALONG A BEXAR COUNTY TO KINNEY COUNTY LINE...
SOUTHWARD...CLOSE TO WHERE HRRR IS INDICATING IT SHOULD BE.
VISIBILITIES SHOULD GRADUALLY IMPROVE 9 AM TO 10 AM.
PREV DISCUSSION... /ISSUED 513 AM CST SUN FEB 8 2015/
AVIATION...
STRATUS WITH IFR/LIFR CIGS AND BR/FG WITH VSBYS AS LOW AS VLIFR
WILL LINGER INTO MID MORNING AND THEN ERODE FROM WEST TO EAST LATE
MORNING INTO EARLY AFTERNOON BY AROUND 19Z. VFR SKIES WILL PREVAIL
FOR THE REST OF TODAY THROUGH MONDAY MORNING AS A DRIER AIRMASS
FILTERS INTO OUR AREA IN THE WAKE OF A SURFACE TROUGH/COLD FRONT.
ALTHOUGH SOME MODELS SHOW SHALLOW MOISTURE AND A POTENTIAL FOR
BR/FG AND STRATUS WITH LIFR/VLIFR CIGS/VSBYS LATE TONIGHT INTO
MONDAY MORNING...WILL LEAVE MENTION OUT AS A DRIER AIRMASS SHOULD
WIN OUT. SWLY WINDS 7 TO 14 KTS WILL TURN NWLY TO NLY AS SURFACE
TROUGH/COLD FRONT MOVES ACROSS THIS AFTERNOON INTO EVENING. SOME
GUSTS UP TO 25 KTS ARE POSSIBLE THIS AFTERNOON.
PREV DISCUSSION... /ISSUED 343 AM CST SUN FEB 8 2015/
SHORT TERM (TODAY THROUGH MONDAY)...LOW STRATUS DECK HAS DEVELOPED
ALONG THE EDGE OF THE ESCARPMENT EARLY THIS MORNING WITH AREAS OF
FOG AND A MIX OF STRATUS ACROSS THE COASTAL PLAINS. HRRR HAS A
DECENT HANDLE ON THE STRATUS THIS MORNING. STRATUS WILL GRADUALLY
SCATTER OUT 10 AM TO 1 PM AS MIXING INCREASES. DRY SOUTHWEST WINDS
TODAY WILL PROMOTE WARM TEMPS...WITH HIGHS IN THE UPPER 70S TO LOW
80S MOST AREAS. SURFACE TROUGH/FRONT MOVES THROUGH THE HILL COUNTRY
AND RIO GRANDE PLAINS MID AFTERNOON...WITH DRY/WARM/BREEZY NORTHWEST
WIND DEVELOPING BEHIND IT. THE TROUGH MOVES EAST OF THE I-35 CORRIDOR
EARLY THIS EVENING. ANY PRECIP SHOULD REMAIN EAST OF THE CWA.
SLIGHTLY COOLER AND DRY ON MONDAY.
LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...DRY CONDITIONS
CONTINUE TUESDAY AS WEAK MID AND UPPER LEVEL RIDGING PASSES
THROUGH THE AREA MONDAY INTO TUESDAY. THE RIDGE FLATTENS AND
SHIFTS EAST TUESDAY NIGHT WITH A SHALLOW MOISTURE RETURN TAKING
PLACE ACROSS SOUTH-CENTRAL TEXAS. AN UPPER LEVEL TROUGH MOVES OUT
OF THE PLAINS WEDNESDAY AND INTO EASTERN CONUS THURSDAY. THIS
SENDS A COLD FRONT THROUGH THE CWA LATE WEDNESDAY OR EARLY
THURSDAY...STILL TIMING DIFFERENCES BETWEEN MODELS. A WEAK UPPER
LEVEL LOW PINCHES OFF FROM THE WESTERN END OF THE TROUGH AXIS OVER
THE SOUTHERN ROCKIES WEDNESDAY...THEN RETROGRADES TO THE SOUTHWEST
ACROSS NORTHWEST MEXICO THU-FRI...BENEATH AMPLIFYING WEST COAST
RIDGE. WITH MOISTURE RETURN AHEAD OF THE FRONT SHALLOW AND DEEPER
FORCING PASSING EAST OF THE AREA WITH THE MAIN TROUGH AXIS AND
WELL WEST WITH THE CUT OFF LOW...POPS ALONG AND BEHIND THE FRONT
WILL REMAIN LOW...LIMITED TO 20-30S MAINLY WEST OF I-35. COOLER
HIGHS THU AND FRI...IN THE MID 50S TO MID 60S.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 80 51 77 49 75 / 0 0 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 77 48 76 44 74 / 0 0 0 0 0
NEW BRAUNFELS MUNI AIRPORT 79 51 76 47 75 / 0 0 0 0 0
BURNET MUNI AIRPORT 78 48 75 46 74 / 0 0 0 0 0
DEL RIO INTL AIRPORT 82 48 78 48 76 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 79 48 76 46 74 / 0 0 0 0 0
HONDO MUNI AIRPORT 81 49 79 45 76 / 0 0 0 0 0
SAN MARCOS MUNI AIRPORT 78 50 76 46 74 / 0 0 0 0 0
LA GRANGE - FAYETTE REGIONAL 78 52 76 47 74 / - - 0 0 0
SAN ANTONIO INTL AIRPORT 80 51 77 48 75 / 0 0 0 0 0
STINSON MUNI AIRPORT 80 51 77 47 76 / 0 0 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...ZEITLER
SYNOPTIC/GRIDS...5
PUBLIC SERVICE/DATA COLLECTION...TREADWAY
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
604 AM CST SUN FEB 8 2015
.UPDATE...SECOND UPDATE TO EXPAND DENSE FOG ADVISORY INTO VAL
VERDE COUNTIES AS WELL AS COUNTIES SURROUNDING BEXAR
COUNTY...BASED ON ASOS AND WEB CAM TRENDS.
&&
.PREV DISCUSSION... /ISSUED 551 AM CST SUN FEB 8 2015/
UPDATE...TRENDS FROM AREA WEBCAMS AND AUTOMATED SURFACE SITES
INDICATE DENSE FOG IS BECOMING WIDESPREAD ENOUGH TO WARRANT A
DENSE FOG ADVISORY ACROSS THE SOUTHWEST CWA. THE DENSE FOG
ADVISORY IS ALONG A BEXAR COUNTY TO KINNEY COUNTY LINE...
SOUTHWARD...CLOSE TO WHERE HRRR IS INDICATING IT SHOULD BE.
VISIBILTIES SHOULD GRADUALLY IMPROVE 9 AM TO 10 AM.
PREV DISCUSSION... /ISSUED 513 AM CST SUN FEB 8 2015/
AVIATION...
STRATUS WITH IFR/LIFR CIGS AND BR/FG WITH VSBYS AS LOW AS VLIFR
WILL LINGER INTO MID MORNING AND THEN ERODE FROM WEST TO EAST LATE
MORNING INTO EARLY AFTERNOON BY AROUND 19Z. VFR SKIES WILL PREVAIL
FOR THE REST OF TODAY THROUGH MONDAY MORNING AS A DRIER AIRMASS
FILTERS INTO OUR AREA IN THE WAKE OF A SURFACE TROUGH/COLD FRONT.
ALTHOUGH SOME MODELS SHOW SHALLOW MOISTURE AND A POTENTIAL FOR
BR/FG AND STRATUS WITH LIFR/VLIFR CIGS/VSBYS LATE TONIGHT INTO
MONDAY MORNING...WILL LEAVE MENTION OUT AS A DRIER AIRMASS SHOULD
WIN OUT. SWLY WINDS 7 TO 14 KTS WILL TURN NWLY TO NLY AS SURFACE
TROUGH/COLD FRONT MOVES ACROSS THIS AFTERNOON INTO EVENING. SOME
GUSTS UP TO 25 KTS ARE POSSIBLE THIS AFTERNOON.
PREV DISCUSSION... /ISSUED 343 AM CST SUN FEB 8 2015/
SHORT TERM (TODAY THROUGH MONDAY)...LOW STRATUS DECK HAS DEVELOPED
ALONG THE EDGE OF THE ESCARPMENT EARLY THIS MORNING WITH AREAS OF
FOG AND A MIX OF STRATUS ACROSS THE COASTAL PLAINS. HRRR HAS A
DECENT HANDLE ON THE STRATUS THIS MORNING. STRATUS WILL GRADUALLY
SCATTER OUT 10 AM TO 1 PM AS MIXING INCREASES. DRY SOUTHWEST WINDS
TODAY WILL PROMOTE WARM TEMPS...WITH HIGHS IN THE UPPER 70S TO LOW
80S MOST AREAS. SURFACE TROUGH/FRONT MOVES THROUGH THE HILL COUNTRY
AND RIO GRANDE PLAINS MID AFTERNOON...WITH DRY/WARM/BREEZY NORTHWEST
WIND DEVELOPING BEHIND IT. THE TROUGH MOVES EAST OF THE I-35 CORRIDOR
EARLY THIS EVENING. ANY PRECIP SHOULD REMAIN EAST OF THE CWA.
SLIGHTLY COOLER AND DRY ON MONDAY.
LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...DRY CONDITIONS
CONTINUE TUESDAY AS WEAK MID AND UPPER LEVEL RIDGING PASSES
THROUGH THE AREA MONDAY INTO TUESDAY. THE RIDGE FLATTENS AND
SHIFTS EAST TUESDAY NIGHT WITH A SHALLOW MOISTURE RETURN TAKING
PLACE ACROSS SOUTH-CENTRAL TEXAS. AN UPPER LEVEL TROUGH MOVES OUT
OF THE PLAINS WEDNESDAY AND INTO EASTERN CONUS THURSDAY. THIS
SENDS A COLD FRONT THROUGH THE CWA LATE WEDNESDAY OR EARLY
THURSDAY...STILL TIMING DIFFERENCES BETWEEN MODELS. A WEAK UPPER
LEVEL LOW PINCHES OFF FROM THE WESTERN END OF THE TROUGH AXIS OVER
THE SOUTHERN ROCKIES WEDNESDAY...THEN RETROGRADES TO THE SOUTHWEST
ACROSS NORTHWEST MEXICO THU-FRI...BENEATH AMPLIFYING WEST COAST
RIDGE. WITH MOISTURE RETURN AHEAD OF THE FRONT SHALLOW AND DEEPER
FORCING PASSING EAST OF THE AREA WITH THE MAIN TROUGH AXIS AND
WELL WEST WITH THE CUT OFF LOW...POPS ALONG AND BEHIND THE FRONT
WILL REMAIN LOW...LIMITED TO 20-30S MAINLY WEST OF I-35. COOLER
HIGHS THU AND FRI...IN THE MID 50S TO MID 60S.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 80 51 77 49 75 / 0 0 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 77 48 76 44 74 / 0 0 0 0 0
NEW BRAUNFELS MUNI AIRPORT 79 51 76 47 75 / 0 0 0 0 0
BURNET MUNI AIRPORT 78 48 75 46 74 / 0 0 0 0 0
DEL RIO INTL AIRPORT 82 48 78 48 76 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 79 48 76 46 74 / 0 0 0 0 0
HONDO MUNI AIRPORT 81 49 79 45 76 / 0 0 0 0 0
SAN MARCOS MUNI AIRPORT 78 50 76 46 74 / 0 0 0 0 0
LA GRANGE - FAYETTE REGIONAL 78 52 76 47 74 / - - 0 0 0
SAN ANTONIO INTL AIRPORT 80 51 77 48 75 / 0 0 0 0 0
STINSON MUNI AIRPORT 80 51 77 47 76 / 0 0 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR THE FOLLOWING
COUNTIES: ATASCOSA...BANDERA...BEXAR...COMAL...DIMMIT...FRIO...
GUADALUPE...KENDALL...KINNEY...MAVERICK...MEDINA...REAL...UVALDE...
VAL VERDE...WILSON...ZAVALA.
&&
$$
MESOSCALE/AVIATION...04
SYNOPTIC/GRIDS...76
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
513 AM CST SUN FEB 8 2015
.AVIATION...
STRATUS WITH IFR/LIFR CIGS AND BR/FG WITH VSBYS AS LOW AS VLIFR
WILL LINGER INTO MID MORNING AND THEN ERODE FROM WEST TO EAST LATE
MORNING INTO EARLY AFTERNOON BY AROUND 19Z. VFR SKIES WILL PREVAIL
FOR THE REST OF TODAY THROUGH MONDAY MORNING AS A DRIER AIRMASS
FILTERS INTO OUR AREA IN THE WAKE OF A SURFACE TROUGH/COLD FRONT.
ALTHOUGH SOME MODELS SHOW SHALLOW MOISTURE AND A POTENTIAL FOR
BR/FG AND STRATUS WITH LIFR/VLIFR CIGS/VSBYS LATE TONIGHT INTO
MONDAY MORNING...WILL LEAVE MENTION OUT AS A DRIER AIRMASS SHOULD
WIN OUT. SWLY WINDS 7 TO 14 KTS WILL TURN NWLY TO NLY AS SURFACE
TROUGH/COLD FRONT MOVES ACROSS THIS AFTERNOON INTO EVENING. SOME
GUSTS UP TO 25 KTS ARE POSSIBLE THIS AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 343 AM CST SUN FEB 8 2015/
SHORT TERM (TODAY THROUGH MONDAY)...LOW STRATUS DECK HAS DEVELOPED
ALONG THE EDGE OF THE ESCARPMENT EARLY THIS MORNING WITH AREAS OF
FOG AND A MIX OF STRATUS ACROSS THE COASTAL PLAINS. HRRR HAS A
DECENT HANDLE ON THE STRATUS THIS MORNING. STRATUS WILL GRADUALLY
SCATTER OUT 10 AM TO 1 PM AS MIXING INCREASES. DRY SOUTHWEST WINDS
TODAY WILL PROMOTE WARM TEMPS...WITH HIGHS IN THE UPPER 70S TO LOW
80S MOST AREAS. SURFACE TROUGH/FRONT MOVES THROUGH THE HILL COUNTRY
AND RIO GRANDE PLAINS MID AFTERNOON...WITH DRY/WARM/BREEZY NORTHWEST
WIND DEVELOPING BEHIND IT. THE TROUGH MOVES EAST OF THE I-35 CORRIDOR
EARLY THIS EVENING. ANY PRECIP SHOULD REMAIN EAST OF THE CWA.
SLIGHTLY COOLER AND DRY ON MONDAY.
LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...DRY CONDITIONS
CONTINUE TUESDAY AS WEAK MID AND UPPER LEVEL RIDGING PASSES
THROUGH THE AREA MONDAY INTO TUESDAY. THE RIDGE FLATTENS AND
SHIFTS EAST TUESDAY NIGHT WITH A SHALLOW MOISTURE RETURN TAKING
PLACE ACROSS SOUTH-CENTRAL TEXAS. AN UPPER LEVEL TROUGH MOVES OUT
OF THE PLAINS WEDNESDAY AND INTO EASTERN CONUS THURSDAY. THIS
SENDS A COLD FRONT THROUGH THE CWA LATE WEDNESDAY OR EARLY
THURSDAY...STILL TIMING DIFFERENCES BETWEEN MODELS. A WEAK UPPER
LEVEL LOW PINCHES OFF FROM THE WESTERN END OF THE TROUGH AXIS OVER
THE SOUTHERN ROCKIES WEDNESDAY...THEN RETROGRADES TO THE SOUTHWEST
ACROSS NORTHWEST MEXICO THU-FRI...BENEATH AMPLIFYING WEST COAST
RIDGE. WITH MOISTURE RETURN AHEAD OF THE FRONT SHALLOW AND DEEPER
FORCING PASSING EAST OF THE AREA WITH THE MAIN TROUGH AXIS AND
WELL WEST WITH THE CUT OFF LOW...POPS ALONG AND BEHIND THE FRONT
WILL REMAIN LOW...LIMITED TO 20-30S MAINLY WEST OF I-35. COOLER
HIGHS THU AND FRI...IN THE MID 50S TO MID 60S.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 80 51 77 49 75 / 0 0 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 77 48 76 44 74 / 0 0 0 0 0
NEW BRAUNFELS MUNI AIRPORT 79 51 76 47 75 / 0 0 0 0 0
BURNET MUNI AIRPORT 78 48 75 46 74 / 0 0 0 0 0
DEL RIO INTL AIRPORT 82 48 78 48 76 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 79 48 76 46 74 / 0 0 0 0 0
HONDO MUNI AIRPORT 81 49 79 45 76 / 0 0 0 0 0
SAN MARCOS MUNI AIRPORT 78 50 76 46 74 / 0 0 0 0 0
LA GRANGE - FAYETTE REGIONAL 78 52 76 47 74 / - - 0 0 0
SAN ANTONIO INTL AIRPORT 80 51 77 48 75 / 0 0 0 0 0
STINSON MUNI AIRPORT 80 51 77 47 76 / 0 0 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...04
SYNOPTIC/GRIDS...76
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
343 AM CST SUN FEB 8 2015
.SHORT TERM (TODAY THROUGH MONDAY)...LOW STRATUS DECK HAS DEVELOPED
ALONG THE EDGE OF THE ESCARPMENT EARLY THIS MORNING WITH AREAS OF
FOG AND A MIX OF STRATUS ACROSS THE COASTAL PLAINS. HRRR HAS A
DECENT HANDLE ON THE STRATUS THIS MORNING. STRATUS WILL GRADUALLY
SCATTER OUT 10 AM TO 1 PM AS MIXING INCREASES. DRY SOUTHWEST WINDS
TODAY WILL PROMOTE WARM TEMPS...WITH HIGHS IN THE UPPER 70S TO LOW
80S MOST AREAS. SURFACE TROUGH/FRONT MOVES THROUGH THE HILL COUNTRY
AND RIO GRANDE PLAINS MID AFTERNOON...WITH DRY/WARM/BREEZY NORTHWEST
WIND DEVELOPING BEHIND IT. THE TROUGH MOVES EAST OF THE I-35 CORRIDOR
EARLY THIS EVENING. ANY PRECIP SHOULD REMAIN EAST OF THE CWA.
SLIGHTLY COOLER AND DRY ON MONDAY.
&&
.LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...DRY CONDITIONS
CONTINUE TUESDAY AS WEAK MID AND UPPER LEVEL RIDGING PASSES
THROUGH THE AREA MONDAY INTO TUESDAY. THE RIDGE FLATTENS AND
SHIFTS EAST TUESDAY NIGHT WITH A SHALLOW MOISTURE RETURN TAKING
PLACE ACROSS SOUTH-CENTRAL TEXAS. AN UPPER LEVEL TROUGH MOVES OUT
OF THE PLAINS WEDNESDAY AND INTO EASTERN CONUS THURSDAY. THIS
SENDS A COLD FRONT THROUGH THE CWA LATE WEDNESDAY OR EARLY
THURSDAY...STILL TIMING DIFFERENCES BETWEEN MODELS. A WEAK UPPER
LEVEL LOW PINCHES OFF FROM THE WESTERN END OF THE TROUGH AXIS OVER
THE SOUTHERN ROCKIES WEDNESDAY...THEN RETROGRADES TO THE SOUTHWEST
ACROSS NORTHWEST MEXICO THU-FRI...BENEATH AMPLIFYING WEST COAST
RIDGE. WITH MOISTURE RETURN AHEAD OF THE FRONT SHALLOW AND DEEPER
FORCING PASSING EAST OF THE AREA WITH THE MAIN TROUGH AXIS AND
WELL WEST WITH THE CUT OFF LOW...POPS ALONG AND BEHIND THE FRONT
WILL REMAIN LOW...LIMITED TO 20-30S MAINLY WEST OF I-35. COOLER
HIGHS THU AND FRI...IN THE MID 50S TO MID 60S.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 80 51 77 49 75 / 0 0 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 77 48 76 44 74 / 0 0 0 0 0
NEW BRAUNFELS MUNI AIRPORT 79 51 76 47 75 / 0 0 0 0 0
BURNET MUNI AIRPORT 78 48 75 46 74 / 0 0 0 0 0
DEL RIO INTL AIRPORT 82 48 78 48 76 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 79 48 76 46 74 / 0 0 0 0 0
HONDO MUNI AIRPORT 81 49 79 45 76 / 0 0 0 0 0
SAN MARCOS MUNI AIRPORT 78 50 76 46 74 / 0 0 0 0 0
LA GRANGE - FAYETTE REGIONAL 78 52 76 47 74 / - - 0 0 0
SAN ANTONIO INTL AIRPORT 80 51 77 48 75 / 0 0 0 0 0
STINSON MUNI AIRPORT 80 51 77 47 76 / 0 0 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...04
SYNOPTIC/GRIDS...76
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1145 PM CST SAT FEB 7 2015
.AVIATION...
MODERATE STRENGTH SURFACE LOW PRESSURE TROUGH WILL MOVE FROM THE
SOUTHEAST PANHANDLE THROUGH THE ROLLING PLAINS EARLY SUNDAY.
FAIRLY PACKED SURFACE PRESSURE GRADIENT ON BACK SIDE WILL MOVE
THROUGH KPVW AND KLBB WHILE A BAND OF STRONG LOW LEVEL WINDS
AROUND 50 KNOTS WITHIN A THOUSAND FEET OF THE GROUND PER LATEST
WEST TEXAS MESONET SODAR PROFILE AT REESE...KREE...PASSES
OVERHEAD. AMENDED EARLIER FOR WIND SHEAR...AND ARE ADJUSTING
SLIGHTLY BASED ON THE KREE SODAR AND LATEST RAP TRENDS. SURFACE
WINDS WILL GRADUALLY TURN MORE NORTHWEST OVERNIGHT AND WE EXPECT
THE BULK OF THE INITIAL JET TO PASS BY 10Z OR SO. SURFACE COLD
FRONT HAS TRENDED SLIGHTLY STRONGER THIS EVENING WITH A PUNCH
SOUTHWARD EXPECTED AROUND DAYBREAK SUNDAY. MOS GUIDANCE INDICATING
A BIT STRONGER SURFACE NORTHERLY WINDS...WITH BOTH RAP AND NAM12
RUNS DEVELOPING A NORTHERLY LOW LEVEL JET JUST OVER 50 KNOTS BUT
WITH BETTER MIXED AIRMASS SHOULD AVOID WIND SHEAR WITH THIS EVENT.
SURFACE WINDS WILL REMAIN GUSTY THROUGH THE MORNING THEN SLOWLY
DECREASE SUNDAY AFTERNOON. VFR OTHERWISE EXPECTED. RMCQUEEN
&&
PREV DISCUSSION... /ISSUED 245 PM CST SAT FEB 7 2015/
SHORT TERM...
THE INITIAL SHORTWV TROUGH THAT WAS RESPONSIBLE FOR GENEROUS PRECIP
ACROSS THE PAC NW LATE FRIDAY INTO EARLY THIS MORNING WILL MOVE
QUICKLY FROM WY/MT INTO THE CENTRAL GREAT PLAINS OVERNIGHT. THIS
WILL HELP PUSH A COLD FRONT SOUTHWARD THROUGH THE AREA DURING THE
DAY SUNDAY. ALTHOUGH COOLER TEMPS WILL EXIST BEHIND THE FRONT THEY
STILL WILL END UP MUCH ABOVE NORMAL THANKS TO NO REAL TAP TO THE
COLD AIR SITTING NORTH OF THE US BORDER. WITH WEAK DOWNSLOPE WINDS
AND DRY SFC AIR IN PLACE AHEAD OF THIS FEATURE EXPECT OVERNIGHT LOWS
TO DROP INTO THE UPPER 30S AND LOWER 40S. AN H8 THERMAL TROUGH WILL
REMAIN IN PLACE THROUGH THE DAY ACROSS THE ROLLING PLAINS WHILE
NORTHERLY FLOW CONTINUES ON THE CAPROCK SO HAVE KEPT TEMPERATURES
FAIRLY UNIFORM FOR THE AREA ON SUNDAY. MEANWHILE NWRLY FLOW AROUND
THE BROAD MID LEVEL RIDGE OVER THE DESERT SW WILL KEEP AMPLE DRY AIR
IN PLACE THROUGH MUCH OF THE TROPOSPHERE RESULTING IN CONTINUED
CLEAR SKIES.
LONG TERM...
SHORT WAVE RIDGING TO MOVE SLOWLY WEST TO EAST ACROSS THE SRN HIGH
PLAINS MONDAY AND TUESDAY RESULTING IN CONTINUATION OF MILD
TEMPERATURES...FAVORING WARMER END OF GUIDANCE RANGE. A COLD FRONT
WILL MOVE THROUGH THE FCST AREA WEDNESDAY TO BRING AN END TO THE
ABOVE NORMAL TEMPERATURES. MODELS CONTINUE TO STRUGGLE WITH
EVOLUTION OF SHORT WAVE ENERGY DIVING SWD DOWN THE BACK SIDE OF AN
AMPLIFYING UPPER RIDGE OVER THE WEST COAST...WITH 12Z RUNS
GENERALLY CONTINUING THE TREND OF BRINGING THIS ENERGY DOWN THE
LEE OF THE ROCKIES THEN SWWD TWD BAJA CALIF AND KEEPING IT THERE
THROUGH NEXT WEEKEND. THAT WILL LEAVE A BRIEF WINDOW FOR SOME
LIGHT PRECIPITATION AS THE TROUGH MOVES SWD PAST COLORADO AND WRN
KANSAS. HOWEVER...PATTERN NOT TERRIBLY CONDUCIVE TO PRECIP. POST-
FRONTAL ISENTROPIC DOWNGLIDE LIKELY TO MOVE IN PRETTY QUICKLY WITH
THE ZONAL FLOW SOUTH OF THE UPPER TROUGH...AND WITH MUCH OF THE
ENERGY DIVING SWWD ATTM SEEMS WRN ZONES WILL FAVORED OVER CNTL AND
EAST. POPS NEAR OR JUST UNDER MOS BEST ATTM. REMAINDER OF THE WEEK
THEN LOOKS FAIR BUT RELATIVELY COOL COMPARED TO RECENT WARM
WEATHER COURTESY OF A MORE AMPLIFIED UPPER PATTER OVER THE CONUS.
FIRE WEATHER...
ELEVATED FIRE WEATHER CONDITIONS WILL CONTINUE THROUGH SUNSET AS
MINIMUM RH VALUES OF 10-15 PERCENT SLOWLY IMPROVE AND GUST WEST-
NORTHWEST WINDS RELAX. 20FT WINDS AROUND 15 MPH WILL REDEVELOP ON
SUNDAY BEHIND A WEAK COLD FRONT. THE WIND WILL COMBINE WITH EARLY
AFTERNOON RH VALUES OF 15-20 PERCENT TO CREATE LIMITED BUT ELEVATED
FIRE WEATHER CONDITIONS PRIMARILY OFF THE CAPROCK.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 38 70 34 72 / 0 0 0 0
TULIA 40 71 34 72 / 0 0 0 0
PLAINVIEW 40 72 35 72 / 0 0 0 0
LEVELLAND 42 74 36 75 / 0 0 0 0
LUBBOCK 41 74 37 76 / 0 0 0 0
DENVER CITY 44 74 37 73 / 0 0 0 0
BROWNFIELD 44 75 37 75 / 0 0 0 0
CHILDRESS 42 74 39 74 / 0 0 0 0
SPUR 44 74 39 77 / 0 0 0 0
ASPERMONT 43 75 42 77 / 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/05
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
912 PM CST MON FEB 9 2015
.UPDATE...
AS LAND BREEZE WEAKENS AND LIGHT EAST FETCH BECOMES MORE
ESTABLISHED...THERE MAY BE A FEW FLURRIES THAT REACH LAND AREAS IN
THE COUNTIES ALONG LAKE MICHIGAN...AS SEEN ON THE REFLECTIVITY
FORECASTS ON THE HRRR AND 00Z NAM.
&&
.AVIATION/06Z TAFS/...
AS LAND BREEZE WEAKENS AND LIGHT EAST FETCH BECOMES MORE
ESTABLISHED...THERE MAY BE A FEW FLURRIES THAT REACH LAND AREAS IN
THE COUNTIES ALONG LAKE MICHIGAN...AS SEEN ON THE REFLECTIVITY
FORECASTS ON THE HRRR AND 00Z NAM. THIS WILL SPREAD SOME THIN MVFR
CLOUDS INLAND...ESPECIALLY OVER SOUTHEAST WISCONSIN LATE TONIGHT
AND TUESDAY MORNING.
OTHERWISE SHOULD SEE MAINLY MID AND HIGH LEVEL CLOUDS FOR MUCH OF
THE DAYTIME HOURS TUESDAY AS A SHORTWAVE APPROACHES.
MAY SEE A LITTLE LIGHT SNOW IN THE NORTHWEST HALF OF THE FORECAST
AREA BY LATE TUESDAY AFTERNOON. LIGHT SNOW IS THEN EXPECTED
ACROSS MUCH OF THE FORECAST AREA DURING THE EVENING HOURS...MAYBE
MIXED WITH LIGHT FREEZING RAIN OR SLEET SOUTH OF MADISON AND
MILWAUKEE. OVERALL SNOW ACCUMULATIONS WILL BE GENERALLY UNDER AN
INCH...THE HIGHEST AMOUNTS TOWARD THE NORTHERN FORECAST AREA.
&&
.PREV DISCUSSION... /ISSUED 402 PM CST MON FEB 9 2015/
TONIGHT AND TUESDAY...FORECAST CONFIDENCE...HIGH...
CLOUDS CONTINUE TO CLEAR OUT ACROSS THE FORECAST AREA THIS
AFTERNOON...WITH LOW CLOUDS ONLY HANGING ON IN THE EAST. MOSTLY
CLEAR TO PARTLY CLOUDY SKIES ARE EXPECTED TONIGHT...EXCEPT FOR NEAR
LAKE MICHIGAN WHERE NORTHEAST LOW LEVEL WINDS MAY BRING IN SOME
LOWER CLOUDS OFF THE LAKE FOR A TIME. LIGHT WINDS AND MOSTLY CLEAR
SKIES SHOULD ALLOW TEMPS TO DROP TO THE UPPER SINGLE DIGITS MOST
PLACES...EXCEPT FOR IN THE EAST WHERE THE CLOUDS AND MILDER AIR OFF
THE LAKE SHOULD KEEP TEMPS A BIT MILDER.
SHOULD SEE MAINLY MID AND HIGH LEVEL CLOUDS FOR MUCH OF THE DAYTIME
HOURS TUESDAY AS A SHORTWAVE APPROACHES. MAY SEE A LITTLE LIGHT SNOW
IN THE NORTHWEST HALF OF THE FORECAST AREA BY LATE TUESDAY
AFTERNOON...POSSIBLY MIXED WITH SLEET SOUTH OF MADISON DUE TO AN
ELEVATED WARM LAYER. HIGHEST SNOW AMOUNTS THROUGH LATE AFTERNOON
WILL BE IN THE FAR NORTHWEST...BUT WILL BE GENERALLY LESS THAN HALF
AN INCH.
TUE NIGHT AND WEDNESDAY...FORECAST CONFIDENCE...HIGH...
LIGHT SNOW IS EXPECTED TO CONTINUE THROUGH THE NIGHT ACROSS THE
NORTHERN HALF OF THE CWA. SOUNDINGS INDICATE THE DENDRITE GROWTH
ZONE DRIES OUT LATE TUESDAY EVENING MAINLY SOUTH OF MADISON AND
MILWAUKEE SO HAVE A CHANCE OF LIGHT FREEZING DRIZZLE AND SLEET
ACROSS SOUTHERN CWA DURING THE NIGHT.
THE MAIN CORE OF PRECIP SHOULD END WED MORNING AS SURFACE TROUGH
AXIS SWINGS THROUGH BUT LIGHT SNOW OR FLURRIES MAY LINGER THROUGH
THE DAY ACROSS THE EAST. THINK ADDITIONAL SNOW ACCUMULATION WILL
BE UP TO ONE INCH IN THE NORTHERN CWA TO A FEW TENTHS IN THE
MADISON AND MILWAUKEE AREAS. WITH THE PASSAGE OF THE SURFACE
TROUGH WINDS WILL BECOME GUSTY OUT OF THE NORTHWEST.
WEDNESDAY NIGHT AND THURSDAY...FORECAST CONFIDENCE...HIGH...
A DEEP 500MB TROUGH DIVES SOUTH THROUGH THE STATE OVERNIGHT WITH
STRONG NORTHWEST FLOW BEHIND IT. HIGH PRESSURE MOVES INTO THE REGION
ON THURSDAY AND 925 TEMPERATURES BOTTOM OUT AROUND -20C. THURSDAY MORNING
WIND CHILL VALUES LOOK TO BE IN THE -15 TO -20 DEGREE RANGE.
FRIDAY THROUGH SUNDAY...FORECAST CONFIDENCE...HIGH...
THE NEXT LOW MOVES NORTH OF THE STATE FRIDAY WITH LIGHT SNOW CHANCES
BRUSHING SOUTHERN WI. SNOW MAY LINGER IN THE FAR EAST THROUGH
SATURDAY. ANOTHER DEEP 500MB TROUGH DIGS SOUTH ACROSS THE STATE ON
SATURDAY BRINGING ANOTHER SURGE OF COLD AIR. WIND CHILL VALUES NEAR -
20 ARE EXPECTED SUNDAY MORNING.
MONDAY AND TUESDAY...FORECAST CONFIDENCE...LOW...
LOW PRESSURE TRACKING SOUTH OF THE STATE WILL BRING THE NEXT CHANCE
OF ACCUMULATING SNOW MON NIGHT INTO TUESDAY. 500MB FLOW BECOMES LESS
AMPLIFIED BUT IS STILL NORTHWESTERLY. MILDER TEMPS EXPECTED FOR THE
EARLY PART OF THE WEEK THEN COLDER AIR RETURNS MIDWEEK WITH ANOTHER
SHORTWAVE TROUGH DIGGING INTO THE STATE.
AVIATION/00Z TAFS/...
CLOUDS CONTINUE TO CLEAR OUT ACROSS THE FORECAST AREA THIS
AFTERNOON...WITH LOW CIGS ONLY HANGING ON IN THE EAST. MOSTLY CLEAR
TO PARTLY CLOUDY SKIES ARE EXPECTED TONIGHT...EXCEPT FOR NEAR LAKE
MICHIGAN WHERE NORTHEAST LOW LEVEL WINDS MAY BRING IN SOME LOWER
CLOUDS OFF THE LAKE FOR A TIME. SHOULD SEE MAINLY MID AND HIGH LEVEL
CLOUDS FOR MUCH OF THE DAYTIME HOURS TUESDAY AS A SHORTWAVE
APPROACHES.
MAY SEE A LITTLE LIGHT SNOW IN THE NORTHWEST HALF OF THE FORECAST
AREA BY LATE TUESDAY AFTERNOON...POSSIBLY MIXED WITH SLEET SOUTH OF
MADISON. LIGHT SNOW IS THEN EXPECTED ACROSS MUCH OF THE FORECAST
AREA DURING THE EVENING HOURS...MAYBE MIXED WITH FREEZING RAIN OR
SLEET SOUTH OF MADISON AND MILWAUKEE. OVERALL SNOW ACCUMULATIONS
WILL BE GENERALLY UNDER AN INCH...THE HIGHEST AMOUNTS TOWARD THE
NORTHERN FORECAST AREA.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...HENTZ
TONIGHT/TUESDAY AND AVIATION/MARINE...DDV
TUESDAY NIGHT THROUGH MONDAY...MARQUARDT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1115 AM CST SUN FEB 8 2015
.UPDATE...
ISSUED AT 1022 AM CST SUN FEB 8 2015
LAST OF THE RAIN THAT WAS CAUSING SOME ICING ISSUES THIS MORNING
WAS MOVING SOUTHEAST OUT OF CLAYTON COUNTY IA/GRANT COUNTY WI.
CALLS TO LAW ENFORCEMENT WHERE THE RAIN WAS FALLING INDICATED
THAT THE PRECIPITATION WAS FALLING AS ALL LIQUID AND ICING WAS NOT
AN ISSUE DUE TO WARMING TEMPERATURES. THEREFORE...THE FREEZING
RAIN ADVISORY WAS ALLOWED TO EXPIRE AT 10 AM.
UPDATE ISSUED AT 506 AM CST SUN FEB 8 2015
LIGHT FREEZING RAIN HAS BEEN OBSERVED HERE AT OUR OFFICE. WITH
THE BAND OF MID LEVEL FRONTOGENESIS AND HIGHER REFLECTIVITIES
STILL MARCHING EAST-SOUTHEASTWARD...FELT IT WAS PRUDENT TO NOW
INCLUDE MOST WISCONSIN COUNTIES ALONG AND SOUTH OF I-90. THE LONE
EXCEPTION WAS JUNEAU/ADAMS WHICH MAY ONLY GET BRUSHED BY THE
LIGHT FREEZING RAIN.
UPDATE ISSUED AT 340 AM CST SUN FEB 8 2015
RADAR REFLECTIVITIES HAVE REALLY BLOSSOMED OVER THE PAST HALF HOUR
ACROSS SOUTHWEST MN. 08.08Z RAP/HRRR AND 08.06Z NAM HAVE A GOOD
HANDLE ON THIS INCREASED POTENTIAL FOR PRECIPITATION...BRINGING IT
THROUGH NORTHEAST IOWA AND SOME OF SOUTHEAST MN OVER THE NEXT 3-6
HOURS. WITH TEMPERATURES STILL FALLING DUE TO A NORTHERLY FLOW IN
PLACE...ANTICIPATE MUCH OF THE PRECIPITATION SHOULD FALL AS
FREEZING RAIN. THEREFORE...IN COLLABORATION WITH MPX AND
DMX...HAVE ISSUED A FREEZING RAIN ADVISORY FOR MOST OF SOUTHEAST
MN AND ALL OF NORTHEAST IOWA. END TIME IS 16Z FOR SIMPLICITY WITH
HAZARDS TO THE WEST BUT SOUTHEAST MN MAY BE ABLE TO BE CANCELLED
BY 14Z. WILL NEED TO MONITOR EXPANDING EAST INTO WISCONSIN OVER
THE NEXT FEW HOURS...BUT RIGHT NOW HIGHEST CONFIDENCE IS WEST OF
THE MISSISSIPPI RIVER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 258 AM CST SUN FEB 8 2015
HIGHLIGHTS / CONCERNS...
1. PRECIPITATION POTENTIAL TODAY AND TYPE.
CURRENTLY AS OF 09Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT
ANALYSIS SHOWED RIDGING OVER THE WESTERN U.S. INTO ALBERTA AND
SASKATCHEWAN WHILE A FAIRLY VIGOROUS SHORTWAVE TROUGH WAS DIGGING
SOUTHEAST THROUGH EASTERN NEBRASKA. THIS SHORTWAVE TROUGH IS
MOISTURE STARVED...DUE TO EXTENSIVE LOW TO MID LEVEL DRY AIR
PRESENT ON 00Z MPX...ABR...BIS AND OAX. HOWEVER...LIGHT
RAIN/FREEZING RAIN HAS FALLEN FROM ABERDEEN TO REDWOOD
FALLS...DODGE CENTER AND WABASHA. THIS LIGHT PRECIPITATION IS
MOSTLY A RESULT OF MID LEVEL FRONTOGENESIS THAT HAS BEEN STRONG
ENOUGH TO GET THE RAIN THROUGH THE DRY AIR BELOW. AIRMASS
SOUTHWEST OF I-94 ACROSS THE FORECAST AREA STILL PRETTY WARM FOR
THIS TIME OF YEAR WITH 850MB TEMPS OF 6-12C AND AIR TEMPERATURES
OF 30-34F. HOWEVER...NORTH OF I-94 AIR TEMPERATURES FALL INTO THE
20S. THIS THERMAL GRADIENT IS REFLECTED BY THE MID LEVEL
FRONTOGENESIS ALOFT...AS WELL AS AT THE SURFACE BY LOW PRESSURE
NEAR CHICAGO WITH A TROUGH EXTENDING BACK INTO EASTERN MT.
EXTENSIVE MID/HIGH CLOUDS EXIST ACROSS THE FORECAST AREA...HELPING
TO HOLD VISIBILITIES UP FROM WHAT WOULD BE FAVORABLE FOG
CONDITIONS. LOWER CLOUDS WERE ALSO PRESENT ALONG/NORTH OF I-94 IN
WISCONSIN.
PRECIPITATION FORECASTING FOR TODAY REMAINS VERY PROBLEMATIC.
FIRST...THE IMPRESSIVE SHORTWAVE OVER EASTERN NEBRASKA REMAINS
PROGGED TO SLIDE WELL SOUTH OF US...REACHING THE INTERSECTION POINT
OF IA...IL AND MO BY 18Z. WE DO SEE A LITTLE DPVA FROM IT...ENOUGH
TO LIKELY BRING THIS CONTINUOUS FEED OF MID AND HIGH CLOUDS ACROSS
THE REGION AS SEEN UPSTREAM OVER CENTRAL MN. SECOND ISSUE AND JUST
AS IMPORTANT IS THIS DRY AIR WE HAVE IN PLACE. BASICALLY THE FOCUS
FOR PRECIPITATION WILL HAVE TO COME ON THIS MID LEVEL FRONTOGENESIS
ZONE THAT HAS BEEN PRODUCING LIGHT RAIN/FREEZING RAIN. THAT ZONE...
PER THE RAP/HRRR AND 08.00Z CANADIAN/GFS/ECMWF...LOOKS TO MOVE OVER
THE REGION AROUND I-90 BY 10Z...THEN SLIP SOUTH THROUGH THE MORNING.
ONCE WE GET TO THE AFTERNOON...THE FRONTOGENESIS IS OUT OF HERE...
ALONG WITH SUBSIDENCE BUILDING IN BEHIND THE SHORTWAVE TO OUR SOUTH
WHICH SHOULD SHUT THE PRECIPITATION OFF. BECAUSE THE DRY AIR IS
EXPECTED TO RESULT IN SPOTTY PRECIPITATION...KEPT PRECIPITATION
CHANCES IN THE 30-50 RANGE.
PRECIPITATION TYPE...THE MAXIMUM WARM LAYER ALOFT TEMPERATURES FOR
THE MORNING FOR WHERE PRECIPITATION IS POSSIBLE ARE GENERALLY AT OR
ABOVE 4C...PER THE 08.00Z GFS/NAM AND LATEST RAP. THERE IS SOME
COOLING THAT TAKES PLACE AS A RESULT OF EVAPORATION...BUT NOT ENOUGH
TO DROP THE AFOREMENTIONED TEMP BELOW 4C BEFORE PRECIPITATION ENDS.
THEREFORE...RAIN/FREEZING RAIN WOULD BE MOST LIKELY TO
OCCUR...DEPENDING ON AIR TEMPERATURE AT THE SURFACE. THOSE AIR
TEMPERATURES SHOULD BE IN THE UPPER 20S/LOW 30S DURING THE BULK OF
THE PRECIPITATION...SO A GLAZE OF ICE COULD OCCUR.
HAZARD CONSIDERATION...THOUGHT ABOUT A FREEZING RAIN ADVISORY BUT
CONFIDENCE IS TOO LOW DUE TO ANTICIPATED SPOTTY NATURE OF THE
FREEZING RAIN. FOR NOW SPECIAL WEATHER STATEMENTS WILL COVER THE
GLAZE POTENTIAL. IF PRECIPITATION COVERAGE INCREASES...ADVISORIES
WOULD BE ISSUED.
OUTSIDE THE PRECIPITATION CONCERNS THIS MORNING...WE SHOULD SEE LOW
STRATUS INCREASE AS INCREASING NORTHEAST 925MB-850MB WINDS PULL THE
STRATUS OVER WISCONSIN SOUTHWESTWARD BEHIND THE DEPARTING SURFACE
LOW. THOSE WINDS REMAIN CYCLONIC THROUGH MUCH OF TONIGHT SO
ANTICIPATING THE STRATUS TO HANG TOUGH. WITH THE COLD ADVECTION
PATTERN DEVELOPING AND CLOUDS AROUND...COOLER TEMPERATURES ARE
LIKELY BOTH TODAY AND TONIGHT. GENERALLY FOLLOWED A CONSENSUS BLEND
FOR HIGHS/LOWS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 258 AM CST SUN FEB 8 2015
HIGHLIGHTS / CONCERNS....
1. PRECIPITATION TUESDAY/TUESDAY NIGHT...AND TYPE.
2. WINDS WEDNESDAY - WEDNESDAY NIGHT
3. ARCTIC COLD SHOT WEDNESDAY NIGHT/THURSDAY WITH ANOTHER ONE
POSSIBLE ON SATURDAY.
SOME OF THE WESTERN U.S. UPPER RIDGING LOOKS TO CROSS THE FORECAST
AREA MONDAY NIGHT IN RESPONSE TO A COLLECTION OF SHORTWAVES MOVING
INTO THE DAKOTAS BY 12Z TUESDAY. THIS UPPER RIDGING COMBINED WITH A
PIECE OF DRIER CANADIAN HIGH PRESSURE MOVING INTO THE FORECAST AREA
ON MONDAY SHOULD HELP TO SCOUR OUT SOME OF THE STRATUS. DESPITE
THE INCREASING SUNSHINE ON MONDAY...925MB TEMPS OF -8 TO -12C WILL
RESULT IN A COOLER DAY COMPARED TO TODAY.
PRECIPITATION CONCERNS CONTINUE FOR TUESDAY INTO TUESDAY NIGHT AS
THE AFOREMENTIONED COLLECTION OF SHORTWAVES MOVE THROUGH THE REGION.
SOME TIMING DIFFERENCES EXIST BETWEEN THE 08.00Z NAM...GFS...
CANADIAN AND ECMWF...BUT THERE IS A STRONG CONSENSUS FOR LOCATIONS
NORTH OF I-90 TO SEE SOME PRECIPITATION. DECENT 285-300K ISENTROPIC
LIFT IS PROGGED...COMBINED WITH THE DPVA FROM THE SHORTWAVES AND
PRECIPITABLE WATER CLIMBING TO OR ABOVE 0.5 INCH ARE ALL FAVORABLE
FOR PRECIPITATION. THUS...HAVE RAISED CHANCES UP SOME NORTH OF I-90.
A WARM LAYER ALOFT WILL NOT IMPACT THE PRECIPITATION TYPE LIKE IT IS
THIS MORNING...HOWEVER...THERE ARE CONCERNS THAT WE COULD LOSE THE
ICE IN THE CLOUDS. THIS SEEMS TO BE MOST PREVALENT SOUTH OF I-90
WHERE CONFIDENCE/AMOUNT OF PRECIPITATION IS LOWER. OVERALL...THIS
TUESDAY/TUESDAY NIGHT PERIOD COULD REQUIRE A WINTER WEATHER ADVISORY
AT SOME POINT. DEFINITELY WORTH MONITORING.
FROM WEDNESDAY AND BEYOND...THE 500MB PATTERN FEATURES RIDGING OVER
MUCH OF WESTERN NORTH AMERICA AND TROUGHING OVER EASTERN NORTH
AMERICA. IN FACT...THE FLOW IS CLOSE TO BECOMING CROSS-POLAR. WHAT
THIS MEANS IS A PATTERN FAVORABLE FOR PERIODIC ARCTIC COLD SHOTS.
THE BIG QUESTION IS HOW FAR WEST WILL THEY BE.
THE FIRST ARCTIC COLD SHOT AFFECTS THE REGION LATE WEDNESDAY INTO
THURSDAY...IN RESPONSE TO A POTENT SHORTWAVE TROUGH DROPPING THROUGH
THE REGION. ITS POSSIBLE SOME LIGHT SNOW COULD PRECEDE THE TROUGH
WEDNESDAY MORNING...PARTICULARLY IN WISCONSIN. OTHERWISE...BRISK
WINDS AND COLD WILL BE THE STORY. 925MB TEMPS PLUMMET TO -18 TO -20C
BY 12Z THU ON A 25-40 KT WIND...SO WIND CHILLS COULD BECOME A FACTOR
THURSDAY MORNING. WITH THE STRONGER WINDS COMING IN HAVE ALSO
INCREASED WIND SPEEDS FOR WEDNESDAY INTO THURSDAY MORNING. COULD SEE
GUSTS 30 KT OR SO IN FAVORED WIND PRONE AREAS. WE GET A BRIEF BREAK
FROM THE COLD ON FRIDAY AS WARM ADVECTION OCCURS AHEAD OF ANOTHER
POTENT SHORTWAVE TROUGH DROPPING DOWN INTO LAKE SUPERIOR. A LITTLE
LIGHT SNOW IS POSSIBLE FROM THIS WARM ADVECTION. THEN...THE ARCTIC
COLD IS LOOKING MORE LIKELY TO RETURN FOR SATURDAY WITH 925MB TEMPS
SIMIALR TO THOSE ON THURSDAY. FOLLOWED A MODEL CONSENSUS FOR HIGHS
ON SATURDAY BUT THESE MAY NEED LOWERING IN FUTURE FORECASTS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1115 AM CST SUN FEB 8 2015
HIGH PRESSURE WILL BUILD INTO THE AREA TODAY INTO MONDAY.
HOWEVER...EXTENSIVE MVFR STRATUS TO LINGER OVER THE REGION
THROUGH THE TAF PERIOD. WINDS WILL BE FROM THE NORTH/NORTHEAST AND
GENERALLY AROUND 10KT OR LESS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...DAS
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1022 AM CST SUN FEB 8 2015
.UPDATE...
ISSUED AT 1022 AM CST SUN FEB 8 2015
LAST OF THE RAIN THAT WAS CAUSING SOME ICING ISSUES THIS MORNING
WAS MOVING SOUTHEAST OUT OF CLAYTON COUNTY IA/GRANT COUNTY WI.
CALLS TO LAW ENFORCEMENT WHERE THE RAIN WAS FALLING INDICATED
THAT THE PRECIPITATION WAS FALLING AS ALL LIQUID AND ICING WAS NOT
AN ISSUE DUE TO WARMING TEMPERATURES. THEREFORE...THE FREEZING
RAIN ADVISORY WAS ALLOWED TO EXPIRE AT 10 AM.
UPDATE ISSUED AT 506 AM CST SUN FEB 8 2015
LIGHT FREEZING RAIN HAS BEEN OBSERVED HERE AT OUR OFFICE. WITH
THE BAND OF MID LEVEL FRONTOGENESIS AND HIGHER REFLECTIVITIES
STILL MARCHING EAST-SOUTHEASTWARD...FELT IT WAS PRUDENT TO NOW
INCLUDE MOST WISCONSIN COUNTIES ALONG AND SOUTH OF I-90. THE LONE
EXCEPTION WAS JUNEAU/ADAMS WHICH MAY ONLY GET BRUSHED BY THE
LIGHT FREEZING RAIN.
UPDATE ISSUED AT 340 AM CST SUN FEB 8 2015
RADAR REFLECTIVITIES HAVE REALLY BLOSSOMED OVER THE PAST HALF HOUR
ACROSS SOUTHWEST MN. 08.08Z RAP/HRRR AND 08.06Z NAM HAVE A GOOD
HANDLE ON THIS INCREASED POTENTIAL FOR PRECIPITATION...BRINGING IT
THROUGH NORTHEAST IOWA AND SOME OF SOUTHEAST MN OVER THE NEXT 3-6
HOURS. WITH TEMPERATURES STILL FALLING DUE TO A NORTHERLY FLOW IN
PLACE...ANTICIPATE MUCH OF THE PRECIPITATION SHOULD FALL AS
FREEZING RAIN. THEREFORE...IN COLLABORATION WITH MPX AND
DMX...HAVE ISSUED A FREEZING RAIN ADVISORY FOR MOST OF SOUTHEAST
MN AND ALL OF NORTHEAST IOWA. END TIME IS 16Z FOR SIMPLICITY WITH
HAZARDS TO THE WEST BUT SOUTHEAST MN MAY BE ABLE TO BE CANCELLED
BY 14Z. WILL NEED TO MONITOR EXPANDING EAST INTO WISCONSIN OVER
THE NEXT FEW HOURS...BUT RIGHT NOW HIGHEST CONFIDENCE IS WEST OF
THE MISSISSIPPI RIVER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 258 AM CST SUN FEB 8 2015
HIGHLIGHTS / CONCERNS...
1. PRECIPITATION POTENTIAL TODAY AND TYPE.
CURRENTLY AS OF 09Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT
ANALYSIS SHOWED RIDGING OVER THE WESTERN U.S. INTO ALBERTA AND
SASKATCHEWAN WHILE A FAIRLY VIGOROUS SHORTWAVE TROUGH WAS DIGGING
SOUTHEAST THROUGH EASTERN NEBRASKA. THIS SHORTWAVE TROUGH IS
MOISTURE STARVED...DUE TO EXTENSIVE LOW TO MID LEVEL DRY AIR
PRESENT ON 00Z MPX...ABR...BIS AND OAX. HOWEVER...LIGHT
RAIN/FREEZING RAIN HAS FALLEN FROM ABERDEEN TO REDWOOD
FALLS...DODGE CENTER AND WABASHA. THIS LIGHT PRECIPITATION IS
MOSTLY A RESULT OF MID LEVEL FRONTOGENESIS THAT HAS BEEN STRONG
ENOUGH TO GET THE RAIN THROUGH THE DRY AIR BELOW. AIRMASS
SOUTHWEST OF I-94 ACROSS THE FORECAST AREA STILL PRETTY WARM FOR
THIS TIME OF YEAR WITH 850MB TEMPS OF 6-12C AND AIR TEMPERATURES
OF 30-34F. HOWEVER...NORTH OF I-94 AIR TEMPERATURES FALL INTO THE
20S. THIS THERMAL GRADIENT IS REFLECTED BY THE MID LEVEL
FRONTOGENESIS ALOFT...AS WELL AS AT THE SURFACE BY LOW PRESSURE
NEAR CHICAGO WITH A TROUGH EXTENDING BACK INTO EASTERN MT.
EXTENSIVE MID/HIGH CLOUDS EXIST ACROSS THE FORECAST AREA...HELPING
TO HOLD VISIBILITIES UP FROM WHAT WOULD BE FAVORABLE FOG
CONDITIONS. LOWER CLOUDS WERE ALSO PRESENT ALONG/NORTH OF I-94 IN
WISCONSIN.
PRECIPITATION FORECASTING FOR TODAY REMAINS VERY PROBLEMATIC.
FIRST...THE IMPRESSIVE SHORTWAVE OVER EASTERN NEBRASKA REMAINS
PROGGED TO SLIDE WELL SOUTH OF US...REACHING THE INTERSECTION POINT
OF IA...IL AND MO BY 18Z. WE DO SEE A LITTLE DPVA FROM IT...ENOUGH
TO LIKELY BRING THIS CONTINUOUS FEED OF MID AND HIGH CLOUDS ACROSS
THE REGION AS SEEN UPSTREAM OVER CENTRAL MN. SECOND ISSUE AND JUST
AS IMPORTANT IS THIS DRY AIR WE HAVE IN PLACE. BASICALLY THE FOCUS
FOR PRECIPITATION WILL HAVE TO COME ON THIS MID LEVEL FRONTOGENESIS
ZONE THAT HAS BEEN PRODUCING LIGHT RAIN/FREEZING RAIN. THAT ZONE...
PER THE RAP/HRRR AND 08.00Z CANADIAN/GFS/ECMWF...LOOKS TO MOVE OVER
THE REGION AROUND I-90 BY 10Z...THEN SLIP SOUTH THROUGH THE MORNING.
ONCE WE GET TO THE AFTERNOON...THE FRONTOGENESIS IS OUT OF HERE...
ALONG WITH SUBSIDENCE BUILDING IN BEHIND THE SHORTWAVE TO OUR SOUTH
WHICH SHOULD SHUT THE PRECIPITATION OFF. BECAUSE THE DRY AIR IS
EXPECTED TO RESULT IN SPOTTY PRECIPITATION...KEPT PRECIPITATION
CHANCES IN THE 30-50 RANGE.
PRECIPITATION TYPE...THE MAXIMUM WARM LAYER ALOFT TEMPERATURES FOR
THE MORNING FOR WHERE PRECIPITATION IS POSSIBLE ARE GENERALLY AT OR
ABOVE 4C...PER THE 08.00Z GFS/NAM AND LATEST RAP. THERE IS SOME
COOLING THAT TAKES PLACE AS A RESULT OF EVAPORATION...BUT NOT ENOUGH
TO DROP THE AFOREMENTIONED TEMP BELOW 4C BEFORE PRECIPITATION ENDS.
THEREFORE...RAIN/FREEZING RAIN WOULD BE MOST LIKELY TO
OCCUR...DEPENDING ON AIR TEMPERATURE AT THE SURFACE. THOSE AIR
TEMPERATURES SHOULD BE IN THE UPPER 20S/LOW 30S DURING THE BULK OF
THE PRECIPITATION...SO A GLAZE OF ICE COULD OCCUR.
HAZARD CONSIDERATION...THOUGHT ABOUT A FREEZING RAIN ADVISORY BUT
CONFIDENCE IS TOO LOW DUE TO ANTICIPATED SPOTTY NATURE OF THE
FREEZING RAIN. FOR NOW SPECIAL WEATHER STATEMENTS WILL COVER THE
GLAZE POTENTIAL. IF PRECIPITATION COVERAGE INCREASES...ADVISORIES
WOULD BE ISSUED.
OUTSIDE THE PRECIPITATION CONCERNS THIS MORNING...WE SHOULD SEE LOW
STRATUS INCREASE AS INCREASING NORTHEAST 925MB-850MB WINDS PULL THE
STRATUS OVER WISCONSIN SOUTHWESTWARD BEHIND THE DEPARTING SURFACE
LOW. THOSE WINDS REMAIN CYCLONIC THROUGH MUCH OF TONIGHT SO
ANTICIPATING THE STRATUS TO HANG TOUGH. WITH THE COLD ADVECTION
PATTERN DEVELOPING AND CLOUDS AROUND...COOLER TEMPERATURES ARE
LIKELY BOTH TODAY AND TONIGHT. GENERALLY FOLLOWED A CONSENSUS BLEND
FOR HIGHS/LOWS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 258 AM CST SUN FEB 8 2015
HIGHLIGHTS / CONCERNS....
1. PRECIPITATION TUESDAY/TUESDAY NIGHT...AND TYPE.
2. WINDS WEDNESDAY - WEDNESDAY NIGHT
3. ARCTIC COLD SHOT WEDNESDAY NIGHT/THURSDAY WITH ANOTHER ONE
POSSIBLE ON SATURDAY.
SOME OF THE WESTERN U.S. UPPER RIDGING LOOKS TO CROSS THE FORECAST
AREA MONDAY NIGHT IN RESPONSE TO A COLLECTION OF SHORTWAVES MOVING
INTO THE DAKOTAS BY 12Z TUESDAY. THIS UPPER RIDGING COMBINED WITH A
PIECE OF DRIER CANADIAN HIGH PRESSURE MOVING INTO THE FORECAST AREA
ON MONDAY SHOULD HELP TO SCOUR OUT SOME OF THE STRATUS. DESPITE
THE INCREASING SUNSHINE ON MONDAY...925MB TEMPS OF -8 TO -12C WILL
RESULT IN A COOLER DAY COMPARED TO TODAY.
PRECIPITATION CONCERNS CONTINUE FOR TUESDAY INTO TUESDAY NIGHT AS
THE AFOREMENTIONED COLLECTION OF SHORTWAVES MOVE THROUGH THE REGION.
SOME TIMING DIFFERENCES EXIST BETWEEN THE 08.00Z NAM...GFS...
CANADIAN AND ECMWF...BUT THERE IS A STRONG CONSENSUS FOR LOCATIONS
NORTH OF I-90 TO SEE SOME PRECIPITATION. DECENT 285-300K ISENTROPIC
LIFT IS PROGGED...COMBINED WITH THE DPVA FROM THE SHORTWAVES AND
PRECIPITABLE WATER CLIMBING TO OR ABOVE 0.5 INCH ARE ALL FAVORABLE
FOR PRECIPITATION. THUS...HAVE RAISED CHANCES UP SOME NORTH OF I-90.
A WARM LAYER ALOFT WILL NOT IMPACT THE PRECIPITATION TYPE LIKE IT IS
THIS MORNING...HOWEVER...THERE ARE CONCERNS THAT WE COULD LOSE THE
ICE IN THE CLOUDS. THIS SEEMS TO BE MOST PREVALENT SOUTH OF I-90
WHERE CONFIDENCE/AMOUNT OF PRECIPITATION IS LOWER. OVERALL...THIS
TUESDAY/TUESDAY NIGHT PERIOD COULD REQUIRE A WINTER WEATHER ADVISORY
AT SOME POINT. DEFINITELY WORTH MONITORING.
FROM WEDNESDAY AND BEYOND...THE 500MB PATTERN FEATURES RIDGING OVER
MUCH OF WESTERN NORTH AMERICA AND TROUGHING OVER EASTERN NORTH
AMERICA. IN FACT...THE FLOW IS CLOSE TO BECOMING CROSS-POLAR. WHAT
THIS MEANS IS A PATTERN FAVORABLE FOR PERIODIC ARCTIC COLD SHOTS.
THE BIG QUESTION IS HOW FAR WEST WILL THEY BE.
THE FIRST ARCTIC COLD SHOT AFFECTS THE REGION LATE WEDNESDAY INTO
THURSDAY...IN RESPONSE TO A POTENT SHORTWAVE TROUGH DROPPING THROUGH
THE REGION. ITS POSSIBLE SOME LIGHT SNOW COULD PRECEDE THE TROUGH
WEDNESDAY MORNING...PARTICULARLY IN WISCONSIN. OTHERWISE...BRISK
WINDS AND COLD WILL BE THE STORY. 925MB TEMPS PLUMMET TO -18 TO -20C
BY 12Z THU ON A 25-40 KT WIND...SO WIND CHILLS COULD BECOME A FACTOR
THURSDAY MORNING. WITH THE STRONGER WINDS COMING IN HAVE ALSO
INCREASED WIND SPEEDS FOR WEDNESDAY INTO THURSDAY MORNING. COULD SEE
GUSTS 30 KT OR SO IN FAVORED WIND PRONE AREAS. WE GET A BRIEF BREAK
FROM THE COLD ON FRIDAY AS WARM ADVECTION OCCURS AHEAD OF ANOTHER
POTENT SHORTWAVE TROUGH DROPPING DOWN INTO LAKE SUPERIOR. A LITTLE
LIGHT SNOW IS POSSIBLE FROM THIS WARM ADVECTION. THEN...THE ARCTIC
COLD IS LOOKING MORE LIKELY TO RETURN FOR SATURDAY WITH 925MB TEMPS
SIMIALR TO THOSE ON THURSDAY. FOLLOWED A MODEL CONSENSUS FOR HIGHS
ON SATURDAY BUT THESE MAY NEED LOWERING IN FUTURE FORECASTS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 542 AM CST SUN FEB 8 2015
LIGHT FREEZING RAIN WILL IMPACT AREAS ALONG INTERSTATE 90 THROUGH
08.14Z...AND NORTHEAST IOWA AND SOUTHWEST WISCONSIN THROUGH
08.16Z. ONCE THE FREEZING RAIN ENDS...A IFR/MVFR DECK WILL MOVE
AND THEN LINGER THROUGH THE REMAINDER OF THE TAF PERIOD. BR IS
CURRENTLY REDUCING VISIBILITIES INTO THE 3 TO 5 STATUE MILE RANGE
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...DAS
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
542 AM CST SUN FEB 8 2015
.UPDATE...
ISSUED AT 506 AM CST SUN FEB 8 2015
LIGHT FREEZING RAIN HAS BEEN OBSERVED HERE AT OUR OFFICE. WITH
THE BAND OF MID LEVEL FRONTOGENESIS AND HIGHER REFLECTIVITIES
STILL MARCHING EAST-SOUTHEASTWARD...FELT IT WAS PRUDENT TO NOW
INCLUDE MOST WISCONSIN COUNTIES ALONG AND SOUTH OF I-90. THE LONE
EXCEPTION WAS JUNEAU/ADAMS WHICH MAY ONLY GET BRUSHED BY THE
LIGHT FREEZING RAIN.
UPDATE ISSUED AT 340 AM CST SUN FEB 8 2015
RADAR REFLECTIVITIES HAVE REALLY BLOSSOMED OVER THE PAST HALF HOUR
ACROSS SOUTHWEST MN. 08.08Z RAP/HRRR AND 08.06Z NAM HAVE A GOOD
HANDLE ON THIS INCREASED POTENTIAL FOR PRECIPITATION...BRINGING IT
THROUGH NORTHEAST IOWA AND SOME OF SOUTHEAST MN OVER THE NEXT 3-6
HOURS. WITH TEMPERATURES STILL FALLING DUE TO A NORTHERLY FLOW IN
PLACE...ANTICIPATE MUCH OF THE PRECIPITATION SHOULD FALL AS
FREEZING RAIN. THEREFORE...IN COLLABORATION WITH MPX AND
DMX...HAVE ISSUED A FREEZING RAIN ADVISORY FOR MOST OF SOUTHEAST
MN AND ALL OF NORTHEAST IOWA. END TIME IS 16Z FOR SIMPLICITY WITH
HAZARDS TO THE WEST BUT SOUTHEAST MN MAY BE ABLE TO BE CANCELLED
BY 14Z. WILL NEED TO MONITOR EXPANDING EAST INTO WISCONSIN OVER
THE NEXT FEW HOURS...BUT RIGHT NOW HIGHEST CONFIDENCE IS WEST OF
THE MISSISSIPPI RIVER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 258 AM CST SUN FEB 8 2015
HIGHLIGHTS / CONCERNS...
1. PRECIPITATION POTENTIAL TODAY AND TYPE.
CURRENTLY AS OF 09Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT
ANALYSIS SHOWED RIDGING OVER THE WESTERN U.S. INTO ALBERTA AND
SASKATCHEWAN WHILE A FAIRLY VIGOROUS SHORTWAVE TROUGH WAS DIGGING
SOUTHEAST THROUGH EASTERN NEBRASKA. THIS SHORTWAVE TROUGH IS
MOISTURE STARVED...DUE TO EXTENSIVE LOW TO MID LEVEL DRY AIR
PRESENT ON 00Z MPX...ABR...BIS AND OAX. HOWEVER...LIGHT
RAIN/FREEZING RAIN HAS FALLEN FROM ABERDEEN TO REDWOOD
FALLS...DODGE CENTER AND WABASHA. THIS LIGHT PRECIPITATION IS
MOSTLY A RESULT OF MID LEVEL FRONTOGENESIS THAT HAS BEEN STRONG
ENOUGH TO GET THE RAIN THROUGH THE DRY AIR BELOW. AIRMASS
SOUTHWEST OF I-94 ACROSS THE FORECAST AREA STILL PRETTY WARM FOR
THIS TIME OF YEAR WITH 850MB TEMPS OF 6-12C AND AIR TEMPERATURES
OF 30-34F. HOWEVER...NORTH OF I-94 AIR TEMPERATURES FALL INTO THE
20S. THIS THERMAL GRADIENT IS REFLECTED BY THE MID LEVEL
FRONTOGENESIS ALOFT...AS WELL AS AT THE SURFACE BY LOW PRESSURE
NEAR CHICAGO WITH A TROUGH EXTENDING BACK INTO EASTERN MT.
EXTENSIVE MID/HIGH CLOUDS EXIST ACROSS THE FORECAST AREA...HELPING
TO HOLD VISIBILITIES UP FROM WHAT WOULD BE FAVORABLE FOG
CONDITIONS. LOWER CLOUDS WERE ALSO PRESENT ALONG/NORTH OF I-94 IN
WISCONSIN.
PRECIPITATION FORECASTING FOR TODAY REMAINS VERY PROBLEMATIC.
FIRST...THE IMPRESSIVE SHORTWAVE OVER EASTERN NEBRASKA REMAINS
PROGGED TO SLIDE WELL SOUTH OF US...REACHING THE INTERSECTION POINT
OF IA...IL AND MO BY 18Z. WE DO SEE A LITTLE DPVA FROM IT...ENOUGH
TO LIKELY BRING THIS CONTINUOUS FEED OF MID AND HIGH CLOUDS ACROSS
THE REGION AS SEEN UPSTREAM OVER CENTRAL MN. SECOND ISSUE AND JUST
AS IMPORTANT IS THIS DRY AIR WE HAVE IN PLACE. BASICALLY THE FOCUS
FOR PRECIPITATION WILL HAVE TO COME ON THIS MID LEVEL FRONTOGENESIS
ZONE THAT HAS BEEN PRODUCING LIGHT RAIN/FREEZING RAIN. THAT ZONE...
PER THE RAP/HRRR AND 08.00Z CANADIAN/GFS/ECMWF...LOOKS TO MOVE OVER
THE REGION AROUND I-90 BY 10Z...THEN SLIP SOUTH THROUGH THE MORNING.
ONCE WE GET TO THE AFTERNOON...THE FRONTOGENESIS IS OUT OF HERE...
ALONG WITH SUBSIDENCE BUILDING IN BEHIND THE SHORTWAVE TO OUR SOUTH
WHICH SHOULD SHUT THE PRECIPITATION OFF. BECAUSE THE DRY AIR IS
EXPECTED TO RESULT IN SPOTTY PRECIPITATION...KEPT PRECIPITATION
CHANCES IN THE 30-50 RANGE.
PRECIPITATION TYPE...THE MAXIMUM WARM LAYER ALOFT TEMPERATURES FOR
THE MORNING FOR WHERE PRECIPITATION IS POSSIBLE ARE GENERALLY AT OR
ABOVE 4C...PER THE 08.00Z GFS/NAM AND LATEST RAP. THERE IS SOME
COOLING THAT TAKES PLACE AS A RESULT OF EVAPORATION...BUT NOT ENOUGH
TO DROP THE AFOREMENTIONED TEMP BELOW 4C BEFORE PRECIPITATION ENDS.
THEREFORE...RAIN/FREEZING RAIN WOULD BE MOST LIKELY TO
OCCUR...DEPENDING ON AIR TEMPERATURE AT THE SURFACE. THOSE AIR
TEMPERATURES SHOULD BE IN THE UPPER 20S/LOW 30S DURING THE BULK OF
THE PRECIPITATION...SO A GLAZE OF ICE COULD OCCUR.
HAZARD CONSIDERATION...THOUGHT ABOUT A FREEZING RAIN ADVISORY BUT
CONFIDENCE IS TOO LOW DUE TO ANTICIPATED SPOTTY NATURE OF THE
FREEZING RAIN. FOR NOW SPECIAL WEATHER STATEMENTS WILL COVER THE
GLAZE POTENTIAL. IF PRECIPITATION COVERAGE INCREASES...ADVISORIES
WOULD BE ISSUED.
OUTSIDE THE PRECIPITATION CONCERNS THIS MORNING...WE SHOULD SEE LOW
STRATUS INCREASE AS INCREASING NORTHEAST 925MB-850MB WINDS PULL THE
STRATUS OVER WISCONSIN SOUTHWESTWARD BEHIND THE DEPARTING SURFACE
LOW. THOSE WINDS REMAIN CYCLONIC THROUGH MUCH OF TONIGHT SO
ANTICIPATING THE STRATUS TO HANG TOUGH. WITH THE COLD ADVECTION
PATTERN DEVELOPING AND CLOUDS AROUND...COOLER TEMPERATURES ARE
LIKELY BOTH TODAY AND TONIGHT. GENERALLY FOLLOWED A CONSENSUS BLEND
FOR HIGHS/LOWS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 258 AM CST SUN FEB 8 2015
HIGHLIGHTS / CONCERNS....
1. PRECIPITATION TUESDAY/TUESDAY NIGHT...AND TYPE.
2. WINDS WEDNESDAY - WEDNESDAY NIGHT
3. ARCTIC COLD SHOT WEDNESDAY NIGHT/THURSDAY WITH ANOTHER ONE
POSSIBLE ON SATURDAY.
SOME OF THE WESTERN U.S. UPPER RIDGING LOOKS TO CROSS THE FORECAST
AREA MONDAY NIGHT IN RESPONSE TO A COLLECTION OF SHORTWAVES MOVING
INTO THE DAKOTAS BY 12Z TUESDAY. THIS UPPER RIDGING COMBINED WITH A
PIECE OF DRIER CANADIAN HIGH PRESSURE MOVING INTO THE FORECAST AREA
ON MONDAY SHOULD HELP TO SCOUR OUT SOME OF THE STRATUS. DESPITE
THE INCREASING SUNSHINE ON MONDAY...925MB TEMPS OF -8 TO -12C WILL
RESULT IN A COOLER DAY COMPARED TO TODAY.
PRECIPITATION CONCERNS CONTINUE FOR TUESDAY INTO TUESDAY NIGHT AS
THE AFOREMENTIONED COLLECTION OF SHORTWAVES MOVE THROUGH THE REGION.
SOME TIMING DIFFERENCES EXIST BETWEEN THE 08.00Z NAM...GFS...
CANADIAN AND ECMWF...BUT THERE IS A STRONG CONSENSUS FOR LOCATIONS
NORTH OF I-90 TO SEE SOME PRECIPITATION. DECENT 285-300K ISENTROPIC
LIFT IS PROGGED...COMBINED WITH THE DPVA FROM THE SHORTWAVES AND
PRECIPITABLE WATER CLIMBING TO OR ABOVE 0.5 INCH ARE ALL FAVORABLE
FOR PRECIPITATION. THUS...HAVE RAISED CHANCES UP SOME NORTH OF I-90.
A WARM LAYER ALOFT WILL NOT IMPACT THE PRECIPITATION TYPE LIKE IT IS
THIS MORNING...HOWEVER...THERE ARE CONCERNS THAT WE COULD LOSE THE
ICE IN THE CLOUDS. THIS SEEMS TO BE MOST PREVALENT SOUTH OF I-90
WHERE CONFIDENCE/AMOUNT OF PRECIPITATION IS LOWER. OVERALL...THIS
TUESDAY/TUESDAY NIGHT PERIOD COULD REQUIRE A WINTER WEATHER ADVISORY
AT SOME POINT. DEFINITELY WORTH MONITORING.
FROM WEDNESDAY AND BEYOND...THE 500MB PATTERN FEATURES RIDGING OVER
MUCH OF WESTERN NORTH AMERICA AND TROUGHING OVER EASTERN NORTH
AMERICA. IN FACT...THE FLOW IS CLOSE TO BECOMING CROSS-POLAR. WHAT
THIS MEANS IS A PATTERN FAVORABLE FOR PERIODIC ARCTIC COLD SHOTS.
THE BIG QUESTION IS HOW FAR WEST WILL THEY BE.
THE FIRST ARCTIC COLD SHOT AFFECTS THE REGION LATE WEDNESDAY INTO
THURSDAY...IN RESPONSE TO A POTENT SHORTWAVE TROUGH DROPPING THROUGH
THE REGION. ITS POSSIBLE SOME LIGHT SNOW COULD PRECEDE THE TROUGH
WEDNESDAY MORNING...PARTICULARLY IN WISCONSIN. OTHERWISE...BRISK
WINDS AND COLD WILL BE THE STORY. 925MB TEMPS PLUMMET TO -18 TO -20C
BY 12Z THU ON A 25-40 KT WIND...SO WIND CHILLS COULD BECOME A FACTOR
THURSDAY MORNING. WITH THE STRONGER WINDS COMING IN HAVE ALSO
INCREASED WIND SPEEDS FOR WEDNESDAY INTO THURSDAY MORNING. COULD SEE
GUSTS 30 KT OR SO IN FAVORED WIND PRONE AREAS. WE GET A BRIEF BREAK
FROM THE COLD ON FRIDAY AS WARM ADVECTION OCCURS AHEAD OF ANOTHER
POTENT SHORTWAVE TROUGH DROPPING DOWN INTO LAKE SUPERIOR. A LITTLE
LIGHT SNOW IS POSSIBLE FROM THIS WARM ADVECTION. THEN...THE ARCTIC
COLD IS LOOKING MORE LIKELY TO RETURN FOR SATURDAY WITH 925MB TEMPS
SIMIALR TO THOSE ON THURSDAY. FOLLOWED A MODEL CONSENSUS FOR HIGHS
ON SATURDAY BUT THESE MAY NEED LOWERING IN FUTURE FORECASTS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 542 AM CST SUN FEB 8 2015
LIGHT FREEZING RAIN WILL IMPACT AREAS ALONG INTERSTATE 90 THROUGH
08.14Z...AND NORTHEAST IOWA AND SOUTHWEST WISCONSIN THROUGH
08.16Z. ONCE THE FREEZING RAIN ENDS...A IFR/MVFR DECK WILL MOVE
AND THEN LINGER THROUGH THE REMAINDER OF THE TAF PERIOD. BR IS
CURRENTLY REDUCING VISIBILITIES INTO THE 3 TO 5 STATUE MILE RANGE
AND THIS WILL LIKELY CONTINUE THROUGH THE TAF TIME PERIOD.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FREEZING RAIN ADVISORY UNTIL 10 AM CST THIS MORNING FOR WIZ041-
042-053>055-061.
MN...FREEZING RAIN ADVISORY UNTIL 10 AM CST THIS MORNING FOR
MNZ086>088-094>096.
IA...FREEZING RAIN ADVISORY UNTIL 10 AM CST THIS MORNING FOR
IAZ008>011-018-019-029-030.
&&
$$
UPDATE...AJ
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
506 AM CST SUN FEB 8 2015
.UPDATE...
ISSUED AT 506 AM CST SUN FEB 8 2015
LIGHT FREEZING RAIN HAS BEEN OBSERVED HERE AT OUR OFFICE. WITH
THE BAND OF MID LEVEL FRONTOGENESIS AND HIGHER REFLECTIVITIES
STILL MARCHING EAST-SOUTHEASTWARD...FELT IT WAS PRUDENT TO NOW
INCLUDE MOST WISCONSIN COUNTIES ALONG AND SOUTH OF I-90. THE LONE
EXCEPTION WAS JUNEAU/ADAMS WHICH MAY ONLY GET BRUSHED BY THE
LIGHT FREEZING RAIN.
UPDATE ISSUED AT 340 AM CST SUN FEB 8 2015
RADAR REFLECTIVITIES HAVE REALLY BLOSSOMED OVER THE PAST HALF HOUR
ACROSS SOUTHWEST MN. 08.08Z RAP/HRRR AND 08.06Z NAM HAVE A GOOD
HANDLE ON THIS INCREASED POTENTIAL FOR PRECIPITATION...BRINGING IT
THROUGH NORTHEAST IOWA AND SOME OF SOUTHEAST MN OVER THE NEXT 3-6
HOURS. WITH TEMPERATURES STILL FALLING DUE TO A NORTHERLY FLOW IN
PLACE...ANTICIPATE MUCH OF THE PRECIPITATION SHOULD FALL AS
FREEZING RAIN. THEREFORE...IN COLLABORATION WITH MPX AND
DMX...HAVE ISSUED A FREEZING RAIN ADVISORY FOR MOST OF SOUTHEAST
MN AND ALL OF NORTHEAST IOWA. END TIME IS 16Z FOR SIMPLICITY WITH
HAZARDS TO THE WEST BUT SOUTHEAST MN MAY BE ABLE TO BE CANCELLED
BY 14Z. WILL NEED TO MONITOR EXPANDING EAST INTO WISCONSIN OVER
THE NEXT FEW HOURS...BUT RIGHT NOW HIGHEST CONFIDENCE IS WEST OF
THE MISSISSIPPI RIVER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 258 AM CST SUN FEB 8 2015
HIGHLIGHTS / CONCERNS...
1. PRECIPITATION POTENTIAL TODAY AND TYPE.
CURRENTLY AS OF 09Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT
ANALYSIS SHOWED RIDGING OVER THE WESTERN U.S. INTO ALBERTA AND
SASKATCHEWAN WHILE A FAIRLY VIGOROUS SHORTWAVE TROUGH WAS DIGGING
SOUTHEAST THROUGH EASTERN NEBRASKA. THIS SHORTWAVE TROUGH IS
MOISTURE STARVED...DUE TO EXTENSIVE LOW TO MID LEVEL DRY AIR
PRESENT ON 00Z MPX...ABR...BIS AND OAX. HOWEVER...LIGHT
RAIN/FREEZING RAIN HAS FALLEN FROM ABERDEEN TO REDWOOD
FALLS...DODGE CENTER AND WABASHA. THIS LIGHT PRECIPITATION IS
MOSTLY A RESULT OF MID LEVEL FRONTOGENESIS THAT HAS BEEN STRONG
ENOUGH TO GET THE RAIN THROUGH THE DRY AIR BELOW. AIRMASS
SOUTHWEST OF I-94 ACROSS THE FORECAST AREA STILL PRETTY WARM FOR
THIS TIME OF YEAR WITH 850MB TEMPS OF 6-12C AND AIR TEMPERATURES
OF 30-34F. HOWEVER...NORTH OF I-94 AIR TEMPERATURES FALL INTO THE
20S. THIS THERMAL GRADIENT IS REFLECTED BY THE MID LEVEL
FRONTOGENESIS ALOFT...AS WELL AS AT THE SURFACE BY LOW PRESSURE
NEAR CHICAGO WITH A TROUGH EXTENDING BACK INTO EASTERN MT.
EXTENSIVE MID/HIGH CLOUDS EXIST ACROSS THE FORECAST AREA...HELPING
TO HOLD VISIBILITIES UP FROM WHAT WOULD BE FAVORABLE FOG
CONDITIONS. LOWER CLOUDS WERE ALSO PRESENT ALONG/NORTH OF I-94 IN
WISCONSIN.
PRECIPITATION FORECASTING FOR TODAY REMAINS VERY PROBLEMATIC.
FIRST...THE IMPRESSIVE SHORTWAVE OVER EASTERN NEBRASKA REMAINS
PROGGED TO SLIDE WELL SOUTH OF US...REACHING THE INTERSECTION POINT
OF IA...IL AND MO BY 18Z. WE DO SEE A LITTLE DPVA FROM IT...ENOUGH
TO LIKELY BRING THIS CONTINUOUS FEED OF MID AND HIGH CLOUDS ACROSS
THE REGION AS SEEN UPSTREAM OVER CENTRAL MN. SECOND ISSUE AND JUST
AS IMPORTANT IS THIS DRY AIR WE HAVE IN PLACE. BASICALLY THE FOCUS
FOR PRECIPITATION WILL HAVE TO COME ON THIS MID LEVEL FRONTOGENESIS
ZONE THAT HAS BEEN PRODUCING LIGHT RAIN/FREEZING RAIN. THAT ZONE...
PER THE RAP/HRRR AND 08.00Z CANADIAN/GFS/ECMWF...LOOKS TO MOVE OVER
THE REGION AROUND I-90 BY 10Z...THEN SLIP SOUTH THROUGH THE MORNING.
ONCE WE GET TO THE AFTERNOON...THE FRONTOGENESIS IS OUT OF HERE...
ALONG WITH SUBSIDENCE BUILDING IN BEHIND THE SHORTWAVE TO OUR SOUTH
WHICH SHOULD SHUT THE PRECIPITATION OFF. BECAUSE THE DRY AIR IS
EXPECTED TO RESULT IN SPOTTY PRECIPITATION...KEPT PRECIPITATION
CHANCES IN THE 30-50 RANGE.
PRECIPITATION TYPE...THE MAXIMUM WARM LAYER ALOFT TEMPERATURES FOR
THE MORNING FOR WHERE PRECIPITATION IS POSSIBLE ARE GENERALLY AT OR
ABOVE 4C...PER THE 08.00Z GFS/NAM AND LATEST RAP. THERE IS SOME
COOLING THAT TAKES PLACE AS A RESULT OF EVAPORATION...BUT NOT ENOUGH
TO DROP THE AFOREMENTIONED TEMP BELOW 4C BEFORE PRECIPITATION ENDS.
THEREFORE...RAIN/FREEZING RAIN WOULD BE MOST LIKELY TO
OCCUR...DEPENDING ON AIR TEMPERATURE AT THE SURFACE. THOSE AIR
TEMPERATURES SHOULD BE IN THE UPPER 20S/LOW 30S DURING THE BULK OF
THE PRECIPITATION...SO A GLAZE OF ICE COULD OCCUR.
HAZARD CONSIDERATION...THOUGHT ABOUT A FREEZING RAIN ADVISORY BUT
CONFIDENCE IS TOO LOW DUE TO ANTICIPATED SPOTTY NATURE OF THE
FREEZING RAIN. FOR NOW SPECIAL WEATHER STATEMENTS WILL COVER THE
GLAZE POTENTIAL. IF PRECIPITATION COVERAGE INCREASES...ADVISORIES
WOULD BE ISSUED.
OUTSIDE THE PRECIPITATION CONCERNS THIS MORNING...WE SHOULD SEE LOW
STRATUS INCREASE AS INCREASING NORTHEAST 925MB-850MB WINDS PULL THE
STRATUS OVER WISCONSIN SOUTHWESTWARD BEHIND THE DEPARTING SURFACE
LOW. THOSE WINDS REMAIN CYCLONIC THROUGH MUCH OF TONIGHT SO
ANTICIPATING THE STRATUS TO HANG TOUGH. WITH THE COLD ADVECTION
PATTERN DEVELOPING AND CLOUDS AROUND...COOLER TEMPERATURES ARE
LIKELY BOTH TODAY AND TONIGHT. GENERALLY FOLLOWED A CONSENSUS BLEND
FOR HIGHS/LOWS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 258 AM CST SUN FEB 8 2015
HIGHLIGHTS / CONCERNS....
1. PRECIPITATION TUESDAY/TUESDAY NIGHT...AND TYPE.
2. WINDS WEDNESDAY - WEDNESDAY NIGHT
3. ARCTIC COLD SHOT WEDNESDAY NIGHT/THURSDAY WITH ANOTHER ONE
POSSIBLE ON SATURDAY.
SOME OF THE WESTERN U.S. UPPER RIDGING LOOKS TO CROSS THE FORECAST
AREA MONDAY NIGHT IN RESPONSE TO A COLLECTION OF SHORTWAVES MOVING
INTO THE DAKOTAS BY 12Z TUESDAY. THIS UPPER RIDGING COMBINED WITH A
PIECE OF DRIER CANADIAN HIGH PRESSURE MOVING INTO THE FORECAST AREA
ON MONDAY SHOULD HELP TO SCOUR OUT SOME OF THE STRATUS. DESPITE
THE INCREASING SUNSHINE ON MONDAY...925MB TEMPS OF -8 TO -12C WILL
RESULT IN A COOLER DAY COMPARED TO TODAY.
PRECIPITATION CONCERNS CONTINUE FOR TUESDAY INTO TUESDAY NIGHT AS
THE AFOREMENTIONED COLLECTION OF SHORTWAVES MOVE THROUGH THE REGION.
SOME TIMING DIFFERENCES EXIST BETWEEN THE 08.00Z NAM...GFS...
CANADIAN AND ECMWF...BUT THERE IS A STRONG CONSENSUS FOR LOCATIONS
NORTH OF I-90 TO SEE SOME PRECIPITATION. DECENT 285-300K ISENTROPIC
LIFT IS PROGGED...COMBINED WITH THE DPVA FROM THE SHORTWAVES AND
PRECIPITABLE WATER CLIMBING TO OR ABOVE 0.5 INCH ARE ALL FAVORABLE
FOR PRECIPITATION. THUS...HAVE RAISED CHANCES UP SOME NORTH OF I-90.
A WARM LAYER ALOFT WILL NOT IMPACT THE PRECIPITATION TYPE LIKE IT IS
THIS MORNING...HOWEVER...THERE ARE CONCERNS THAT WE COULD LOSE THE
ICE IN THE CLOUDS. THIS SEEMS TO BE MOST PREVALENT SOUTH OF I-90
WHERE CONFIDENCE/AMOUNT OF PRECIPITATION IS LOWER. OVERALL...THIS
TUESDAY/TUESDAY NIGHT PERIOD COULD REQUIRE A WINTER WEATHER ADVISORY
AT SOME POINT. DEFINITELY WORTH MONITORING.
FROM WEDNESDAY AND BEYOND...THE 500MB PATTERN FEATURES RIDGING OVER
MUCH OF WESTERN NORTH AMERICA AND TROUGHING OVER EASTERN NORTH
AMERICA. IN FACT...THE FLOW IS CLOSE TO BECOMING CROSS-POLAR. WHAT
THIS MEANS IS A PATTERN FAVORABLE FOR PERIODIC ARCTIC COLD SHOTS.
THE BIG QUESTION IS HOW FAR WEST WILL THEY BE.
THE FIRST ARCTIC COLD SHOT AFFECTS THE REGION LATE WEDNESDAY INTO
THURSDAY...IN RESPONSE TO A POTENT SHORTWAVE TROUGH DROPPING THROUGH
THE REGION. ITS POSSIBLE SOME LIGHT SNOW COULD PRECEDE THE TROUGH
WEDNESDAY MORNING...PARTICULARLY IN WISCONSIN. OTHERWISE...BRISK
WINDS AND COLD WILL BE THE STORY. 925MB TEMPS PLUMMET TO -18 TO -20C
BY 12Z THU ON A 25-40 KT WIND...SO WIND CHILLS COULD BECOME A FACTOR
THURSDAY MORNING. WITH THE STRONGER WINDS COMING IN HAVE ALSO
INCREASED WIND SPEEDS FOR WEDNESDAY INTO THURSDAY MORNING. COULD SEE
GUSTS 30 KT OR SO IN FAVORED WIND PRONE AREAS. WE GET A BRIEF BREAK
FROM THE COLD ON FRIDAY AS WARM ADVECTION OCCURS AHEAD OF ANOTHER
POTENT SHORTWAVE TROUGH DROPPING DOWN INTO LAKE SUPERIOR. A LITTLE
LIGHT SNOW IS POSSIBLE FROM THIS WARM ADVECTION. THEN...THE ARCTIC
COLD IS LOOKING MORE LIKELY TO RETURN FOR SATURDAY WITH 925MB TEMPS
SIMIALR TO THOSE ON THURSDAY. FOLLOWED A MODEL CONSENSUS FOR HIGHS
ON SATURDAY BUT THESE MAY NEED LOWERING IN FUTURE FORECASTS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1146 PM CST SAT FEB 7 2015
MVFR/IFR FOG CONTINUES TO BE A PROBLEM OVERNIGHT AND MUCH OF SUNDAY.
SFC LOW WAS MOVING SOUTHEAST OF THE AREA LATE THIS EVENING WITH
LIGHT NORTH WINDS STARTING TO SPREAD INTO TAF SITES...FOR SOME
BOUNDARY LAYER STIRRING. THICKER MID/HIGH CLOUDS WERE SPREADING OVER
THE AREA AS WELL. VSBYS IN BR IN THE 2-5SM RANGE LATE THIS EVENING
AND APPEARS THESE VSBYS WILL GENERALLY HOLD THRU THE OVERNIGHT HOURS
AND SUNDAY MORNING. MVFR STRATUS CLOUDS WERE JUST NORTH/EAST OF KLSE
AND WITH SFC-900MB WINDS TO BECOME NORTH-NORTHEAST OVERNIGHT...THESE
CLOUDS LOOKING TO ADVECT INTO THE KLSE/KRST AREAS LATER TONIGHT.
LATEST MODELS HAVE TRENDED DRIER IN THE 850-700MB LAYER SUNDAY...AS
A MID LEVEL SHORTWAVE PASSES. WENT BACK TO A VCSH MENTION AT
KRST/KLSE 15Z-20Z WITH WHAT NOW LOOKS TO BE MORE OF A 20-30 PERCENT
CHANCE OF SOME VERY LIGHT MIXED PRECIP. NORTH-NORTHEAST LOWER LEVEL
WINDS CONTINUE TO ADVECT PLENTY OF 925-850MB MOISTURE OVER THE AREA
SUN AFTERNOON/EVENING...WITH MVFR/LCL IFR CIGS PERSISTING.
HOWEVER...DRIER/COOLER SFC FLOW FROM THE NORTHEAST SHOULD SCOUR OUT
MUCH OF THE BR/HZ THRU THE LATER AFTERNOON/EVENING HOURS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FREEZING RAIN ADVISORY UNTIL 10 AM CST THIS MORNING FOR WIZ041-
042-053>055-061.
MN...FREEZING RAIN ADVISORY UNTIL 10 AM CST THIS MORNING FOR
MNZ086>088-094>096.
IA...FREEZING RAIN ADVISORY UNTIL 10 AM CST THIS MORNING FOR
IAZ008>011-018-019-029-030.
&&
$$
UPDATE...AJ
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
340 AM CST SUN FEB 8 2015
.UPDATE...
ISSUED AT 340 AM CST SUN FEB 8 2015
RADAR REFLECTIVITIES HAVE REALLY BLOSSOMED OVER THE PAST HALF HOUR
ACROSS SOUTHWEST MN. 08.08Z RAP/HRRR AND 08.06Z NAM HAVE A GOOD
HANDLE ON THIS INCREASED POTENTIAL FOR PRECIPITATION...BRINGING IT
THROUGH NORTHEAST IOWA AND SOME OF SOUTHEAST MN OVER THE NEXT 3-6
HOURS. WITH TEMPERATURES STILL FALLING DUE TO A NORTHERLY FLOW IN
PLACE...ANTICIPATE MUCH OF THE PRECIPITATION SHOULD FALL AS
FREEZING RAIN. THEREFORE...IN COLLABORATION WITH MPX AND
DMX...HAVE ISSUED A FREEZING RAIN ADVISORY FOR MOST OF SOUTHEAST
MN AND ALL OF NORTHEAST IOWA. END TIME IS 16Z FOR SIMPLICITY WITH
HAZARDS TO THE WEST BUT SOUTHEAST MN MAY BE ABLE TO BE CANCELLED
BY 14Z. WILL NEED TO MONITOR EXPANDING EAST INTO WISCONSIN OVER
THE NEXT FEW HOURS...BUT RIGHT NOW HIGHEST CONFIDENCE IS WEST OF
THE MISSISSIPPI RIVER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 258 AM CST SUN FEB 8 2015
HIGHLIGHTS / CONCERNS...
1. PRECIPITATION POTENTIAL TODAY AND TYPE.
CURRENTLY AS OF 09Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT
ANALYSIS SHOWED RIDGING OVER THE WESTERN U.S. INTO ALBERTA AND
SASKATCHEWAN WHILE A FAIRLY VIGOROUS SHORTWAVE TROUGH WAS DIGGING
SOUTHEAST THROUGH EASTERN NEBRASKA. THIS SHORTWAVE TROUGH IS
MOISTURE STARVED...DUE TO EXTENSIVE LOW TO MID LEVEL DRY AIR
PRESENT ON 00Z MPX...ABR...BIS AND OAX. HOWEVER...LIGHT
RAIN/FREEZING RAIN HAS FALLEN FROM ABERDEEN TO REDWOOD
FALLS...DODGE CENTER AND WABASHA. THIS LIGHT PRECIPITATION IS
MOSTLY A RESULT OF MID LEVEL FRONTOGENESIS THAT HAS BEEN STRONG
ENOUGH TO GET THE RAIN THROUGH THE DRY AIR BELOW. AIRMASS
SOUTHWEST OF I-94 ACROSS THE FORECAST AREA STILL PRETTY WARM FOR
THIS TIME OF YEAR WITH 850MB TEMPS OF 6-12C AND AIR TEMPERATURES
OF 30-34F. HOWEVER...NORTH OF I-94 AIR TEMPERATURES FALL INTO THE
20S. THIS THERMAL GRADIENT IS REFLECTED BY THE MID LEVEL
FRONTOGENESIS ALOFT...AS WELL AS AT THE SURFACE BY LOW PRESSURE
NEAR CHICAGO WITH A TROUGH EXTENDING BACK INTO EASTERN MT.
EXTENSIVE MID/HIGH CLOUDS EXIST ACROSS THE FORECAST AREA...HELPING
TO HOLD VISIBILITIES UP FROM WHAT WOULD BE FAVORABLE FOG
CONDITIONS. LOWER CLOUDS WERE ALSO PRESENT ALONG/NORTH OF I-94 IN
WISCONSIN.
PRECIPITATION FORECASTING FOR TODAY REMAINS VERY PROBLEMATIC.
FIRST...THE IMPRESSIVE SHORTWAVE OVER EASTERN NEBRASKA REMAINS
PROGGED TO SLIDE WELL SOUTH OF US...REACHING THE INTERSECTION POINT
OF IA...IL AND MO BY 18Z. WE DO SEE A LITTLE DPVA FROM IT...ENOUGH
TO LIKELY BRING THIS CONTINUOUS FEED OF MID AND HIGH CLOUDS ACROSS
THE REGION AS SEEN UPSTREAM OVER CENTRAL MN. SECOND ISSUE AND JUST
AS IMPORTANT IS THIS DRY AIR WE HAVE IN PLACE. BASICALLY THE FOCUS
FOR PRECIPITATION WILL HAVE TO COME ON THIS MID LEVEL FRONTOGENESIS
ZONE THAT HAS BEEN PRODUCING LIGHT RAIN/FREEZING RAIN. THAT ZONE...
PER THE RAP/HRRR AND 08.00Z CANADIAN/GFS/ECMWF...LOOKS TO MOVE OVER
THE REGION AROUND I-90 BY 10Z...THEN SLIP SOUTH THROUGH THE MORNING.
ONCE WE GET TO THE AFTERNOON...THE FRONTOGENESIS IS OUT OF HERE...
ALONG WITH SUBSIDENCE BUILDING IN BEHIND THE SHORTWAVE TO OUR SOUTH
WHICH SHOULD SHUT THE PRECIPITATION OFF. BECAUSE THE DRY AIR IS
EXPECTED TO RESULT IN SPOTTY PRECIPITATION...KEPT PRECIPITATION
CHANCES IN THE 30-50 RANGE.
PRECIPITATION TYPE...THE MAXIMUM WARM LAYER ALOFT TEMPERATURES FOR
THE MORNING FOR WHERE PRECIPITATION IS POSSIBLE ARE GENERALLY AT OR
ABOVE 4C...PER THE 08.00Z GFS/NAM AND LATEST RAP. THERE IS SOME
COOLING THAT TAKES PLACE AS A RESULT OF EVAPORATION...BUT NOT ENOUGH
TO DROP THE AFOREMENTIONED TEMP BELOW 4C BEFORE PRECIPITATION ENDS.
THEREFORE...RAIN/FREEZING RAIN WOULD BE MOST LIKELY TO
OCCUR...DEPENDING ON AIR TEMPERATURE AT THE SURFACE. THOSE AIR
TEMPERATURES SHOULD BE IN THE UPPER 20S/LOW 30S DURING THE BULK OF
THE PRECIPITATION...SO A GLAZE OF ICE COULD OCCUR.
HAZARD CONSIDERATION...THOUGHT ABOUT A FREEZING RAIN ADVISORY BUT
CONFIDENCE IS TOO LOW DUE TO ANTICIPATED SPOTTY NATURE OF THE
FREEZING RAIN. FOR NOW SPECIAL WEATHER STATEMENTS WILL COVER THE
GLAZE POTENTIAL. IF PRECIPITATION COVERAGE INCREASES...ADVISORIES
WOULD BE ISSUED.
OUTSIDE THE PRECIPITATION CONCERNS THIS MORNING...WE SHOULD SEE LOW
STRATUS INCREASE AS INCREASING NORTHEAST 925MB-850MB WINDS PULL THE
STRATUS OVER WISCONSIN SOUTHWESTWARD BEHIND THE DEPARTING SURFACE
LOW. THOSE WINDS REMAIN CYCLONIC THROUGH MUCH OF TONIGHT SO
ANTICIPATING THE STRATUS TO HANG TOUGH. WITH THE COLD ADVECTION
PATTERN DEVELOPING AND CLOUDS AROUND...COOLER TEMPERATURES ARE
LIKELY BOTH TODAY AND TONIGHT. GENERALLY FOLLOWED A CONSENSUS BLEND
FOR HIGHS/LOWS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 258 AM CST SUN FEB 8 2015
HIGHLIGHTS / CONCERNS....
1. PRECIPITATION TUESDAY/TUESDAY NIGHT...AND TYPE.
2. WINDS WEDNESDAY - WEDNESDAY NIGHT
3. ARCTIC COLD SHOT WEDNESDAY NIGHT/THURSDAY WITH ANOTHER ONE
POSSIBLE ON SATURDAY.
SOME OF THE WESTERN U.S. UPPER RIDGING LOOKS TO CROSS THE FORECAST
AREA MONDAY NIGHT IN RESPONSE TO A COLLECTION OF SHORTWAVES MOVING
INTO THE DAKOTAS BY 12Z TUESDAY. THIS UPPER RIDGING COMBINED WITH A
PIECE OF DRIER CANADIAN HIGH PRESSURE MOVING INTO THE FORECAST AREA
ON MONDAY SHOULD HELP TO SCOUR OUT SOME OF THE STRATUS. DESPITE
THE INCREASING SUNSHINE ON MONDAY...925MB TEMPS OF -8 TO -12C WILL
RESULT IN A COOLER DAY COMPARED TO TODAY.
PRECIPITATION CONCERNS CONTINUE FOR TUESDAY INTO TUESDAY NIGHT AS
THE AFOREMENTIONED COLLECTION OF SHORTWAVES MOVE THROUGH THE REGION.
SOME TIMING DIFFERENCES EXIST BETWEEN THE 08.00Z NAM...GFS...
CANADIAN AND ECMWF...BUT THERE IS A STRONG CONSENSUS FOR LOCATIONS
NORTH OF I-90 TO SEE SOME PRECIPITATION. DECENT 285-300K ISENTROPIC
LIFT IS PROGGED...COMBINED WITH THE DPVA FROM THE SHORTWAVES AND
PRECIPITABLE WATER CLIMBING TO OR ABOVE 0.5 INCH ARE ALL FAVORABLE
FOR PRECIPITATION. THUS...HAVE RAISED CHANCES UP SOME NORTH OF I-90.
A WARM LAYER ALOFT WILL NOT IMPACT THE PRECIPITATION TYPE LIKE IT IS
THIS MORNING...HOWEVER...THERE ARE CONCERNS THAT WE COULD LOSE THE
ICE IN THE CLOUDS. THIS SEEMS TO BE MOST PREVALENT SOUTH OF I-90
WHERE CONFIDENCE/AMOUNT OF PRECIPITATION IS LOWER. OVERALL...THIS
TUESDAY/TUESDAY NIGHT PERIOD COULD REQUIRE A WINTER WEATHER ADVISORY
AT SOME POINT. DEFINITELY WORTH MONITORING.
FROM WEDNESDAY AND BEYOND...THE 500MB PATTERN FEATURES RIDGING OVER
MUCH OF WESTERN NORTH AMERICA AND TROUGHING OVER EASTERN NORTH
AMERICA. IN FACT...THE FLOW IS CLOSE TO BECOMING CROSS-POLAR. WHAT
THIS MEANS IS A PATTERN FAVORABLE FOR PERIODIC ARCTIC COLD SHOTS.
THE BIG QUESTION IS HOW FAR WEST WILL THEY BE.
THE FIRST ARCTIC COLD SHOT AFFECTS THE REGION LATE WEDNESDAY INTO
THURSDAY...IN RESPONSE TO A POTENT SHORTWAVE TROUGH DROPPING THROUGH
THE REGION. ITS POSSIBLE SOME LIGHT SNOW COULD PRECEDE THE TROUGH
WEDNESDAY MORNING...PARTICULARLY IN WISCONSIN. OTHERWISE...BRISK
WINDS AND COLD WILL BE THE STORY. 925MB TEMPS PLUMMET TO -18 TO -20C
BY 12Z THU ON A 25-40 KT WIND...SO WIND CHILLS COULD BECOME A FACTOR
THURSDAY MORNING. WITH THE STRONGER WINDS COMING IN HAVE ALSO
INCREASED WIND SPEEDS FOR WEDNESDAY INTO THURSDAY MORNING. COULD SEE
GUSTS 30 KT OR SO IN FAVORED WIND PRONE AREAS. WE GET A BRIEF BREAK
FROM THE COLD ON FRIDAY AS WARM ADVECTION OCCURS AHEAD OF ANOTHER
POTENT SHORTWAVE TROUGH DROPPING DOWN INTO LAKE SUPERIOR. A LITTLE
LIGHT SNOW IS POSSIBLE FROM THIS WARM ADVECTION. THEN...THE ARCTIC
COLD IS LOOKING MORE LIKELY TO RETURN FOR SATURDAY WITH 925MB TEMPS
SIMIALR TO THOSE ON THURSDAY. FOLLOWED A MODEL CONSENSUS FOR HIGHS
ON SATURDAY BUT THESE MAY NEED LOWERING IN FUTURE FORECASTS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1146 PM CST SAT FEB 7 2015
MVFR/IFR FOG CONTINUES TO BE A PROBLEM OVERNIGHT AND MUCH OF SUNDAY.
SFC LOW WAS MOVING SOUTHEAST OF THE AREA LATE THIS EVENING WITH
LIGHT NORTH WINDS STARTING TO SPREAD INTO TAF SITES...FOR SOME
BOUNDARY LAYER STIRRING. THICKER MID/HIGH CLOUDS WERE SPREADING OVER
THE AREA AS WELL. VSBYS IN BR IN THE 2-5SM RANGE LATE THIS EVENING
AND APPEARS THESE VSBYS WILL GENERALLY HOLD THRU THE OVERNIGHT HOURS
AND SUNDAY MORNING. MVFR STRATUS CLOUDS WERE JUST NORTH/EAST OF KLSE
AND WITH SFC-900MB WINDS TO BECOME NORTH-NORTHEAST OVERNIGHT...THESE
CLOUDS LOOKING TO ADVECT INTO THE KLSE/KRST AREAS LATER TONIGHT.
LATEST MODELS HAVE TRENDED DRIER IN THE 850-700MB LAYER SUNDAY...AS
A MID LEVEL SHORTWAVE PASSES. WENT BACK TO A VCSH MENTION AT
KRST/KLSE 15Z-20Z WITH WHAT NOW LOOKS TO BE MORE OF A 20-30 PERCENT
CHANCE OF SOME VERY LIGHT MIXED PRECIP. NORTH-NORTHEAST LOWER LEVEL
WINDS CONTINUE TO ADVECT PLENTY OF 925-850MB MOISTURE OVER THE AREA
SUN AFTERNOON/EVENING...WITH MVFR/LCL IFR CIGS PERSISTING.
HOWEVER...DRIER/COOLER SFC FLOW FROM THE NORTHEAST SHOULD SCOUR OUT
MUCH OF THE BR/HZ THRU THE LATER AFTERNOON/EVENING HOURS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...FREEZING RAIN ADVISORY UNTIL 10 AM CST THIS MORNING FOR
MNZ086>088-094>096.
IA...FREEZING RAIN ADVISORY UNTIL 10 AM CST THIS MORNING FOR
IAZ008>011-018-019-029-030.
&&
$$
UPDATE...AJ
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
258 AM CST SUN FEB 8 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 258 AM CST SUN FEB 8 2015
HIGHLIGHTS / CONCERNS...
1. PRECIPITATION POTENTIAL TODAY AND TYPE.
CURRENTLY AS OF 09Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT
ANALYSIS SHOWED RIDGING OVER THE WESTERN U.S. INTO ALBERTA AND
SASKATCHEWAN WHILE A FAIRLY VIGOROUS SHORTWAVE TROUGH WAS DIGGING
SOUTHEAST THROUGH EASTERN NEBRASKA. THIS SHORTWAVE TROUGH IS
MOISTURE STARVED...DUE TO EXTENSIVE LOW TO MID LEVEL DRY AIR
PRESENT ON 00Z MPX...ABR...BIS AND OAX. HOWEVER...LIGHT
RAIN/FREEZING RAIN HAS FALLEN FROM ABERDEEN TO REDWOOD
FALLS...DODGE CENTER AND WABASHA. THIS LIGHT PRECIPITATION IS
MOSTLY A RESULT OF MID LEVEL FRONTOGENESIS THAT HAS BEEN STRONG
ENOUGH TO GET THE RAIN THROUGH THE DRY AIR BELOW. AIRMASS
SOUTHWEST OF I-94 ACROSS THE FORECAST AREA STILL PRETTY WARM FOR
THIS TIME OF YEAR WITH 850MB TEMPS OF 6-12C AND AIR TEMPERATURES
OF 30-34F. HOWEVER...NORTH OF I-94 AIR TEMPERATURES FALL INTO THE
20S. THIS THERMAL GRADIENT IS REFLECTED BY THE MID LEVEL
FRONTOGENESIS ALOFT...AS WELL AS AT THE SURFACE BY LOW PRESSURE
NEAR CHICAGO WITH A TROUGH EXTENDING BACK INTO EASTERN MT.
EXTENSIVE MID/HIGH CLOUDS EXIST ACROSS THE FORECAST AREA...HELPING
TO HOLD VISIBILITIES UP FROM WHAT WOULD BE FAVORABLE FOG
CONDITIONS. LOWER CLOUDS WERE ALSO PRESENT ALONG/NORTH OF I-94 IN
WISCONSIN.
PRECIPITATION FORECASTING FOR TODAY REMAINS VERY PROBLEMATIC.
FIRST...THE IMPRESSIVE SHORTWAVE OVER EASTERN NEBRASKA REMAINS
PROGGED TO SLIDE WELL SOUTH OF US...REACHING THE INTERSECTION POINT
OF IA...IL AND MO BY 18Z. WE DO SEE A LITTLE DPVA FROM IT...ENOUGH
TO LIKELY BRING THIS CONTINUOUS FEED OF MID AND HIGH CLOUDS ACROSS
THE REGION AS SEEN UPSTREAM OVER CENTRAL MN. SECOND ISSUE AND JUST
AS IMPORTANT IS THIS DRY AIR WE HAVE IN PLACE. BASICALLY THE FOCUS
FOR PRECIPITATION WILL HAVE TO COME ON THIS MID LEVEL FRONTOGENESIS
ZONE THAT HAS BEEN PRODUCING LIGHT RAIN/FREEZING RAIN. THAT ZONE...
PER THE RAP/HRRR AND 08.00Z CANADIAN/GFS/ECMWF...LOOKS TO MOVE OVER
THE REGION AROUND I-90 BY 10Z...THEN SLIP SOUTH THROUGH THE MORNING.
ONCE WE GET TO THE AFTERNOON...THE FRONTOGENESIS IS OUT OF HERE...
ALONG WITH SUBSIDENCE BUILDING IN BEHIND THE SHORTWAVE TO OUR SOUTH
WHICH SHOULD SHUT THE PRECIPITATION OFF. BECAUSE THE DRY AIR IS
EXPECTED TO RESULT IN SPOTTY PRECIPITATION...KEPT PRECIPITATION
CHANCES IN THE 30-50 RANGE.
PRECIPITATION TYPE...THE MAXIMUM WARM LAYER ALOFT TEMPERATURES FOR
THE MORNING FOR WHERE PRECIPITATION IS POSSIBLE ARE GENERALLY AT OR
ABOVE 4C...PER THE 08.00Z GFS/NAM AND LATEST RAP. THERE IS SOME
COOLING THAT TAKES PLACE AS A RESULT OF EVAPORATION...BUT NOT ENOUGH
TO DROP THE AFOREMENTIONED TEMP BELOW 4C BEFORE PRECIPITATION ENDS.
THEREFORE...RAIN/FREEZING RAIN WOULD BE MOST LIKELY TO
OCCUR...DEPENDING ON AIR TEMPERATURE AT THE SURFACE. THOSE AIR
TEMPERATURES SHOULD BE IN THE UPPER 20S/LOW 30S DURING THE BULK OF
THE PRECIPITATION...SO A GLAZE OF ICE COULD OCCUR.
HAZARD CONSIDERATION...THOUGHT ABOUT A FREEZING RAIN ADVISORY BUT
CONFIDENCE IS TOO LOW DUE TO ANTICIPATED SPOTTY NATURE OF THE
FREEZING RAIN. FOR NOW SPECIAL WEATHER STATEMENTS WILL COVER THE
GLAZE POTENTIAL. IF PRECIPITATION COVERAGE INCREASES...ADVISORIES
WOULD BE ISSUED.
OUTSIDE THE PRECIPITATION CONCERNS THIS MORNING...WE SHOULD SEE LOW
STRATUS INCREASE AS INCREASING NORTHEAST 925MB-850MB WINDS PULL THE
STRATUS OVER WISCONSIN SOUTHWESTWARD BEHIND THE DEPARTING SURFACE
LOW. THOSE WINDS REMAIN CYCLONIC THROUGH MUCH OF TONIGHT SO
ANTICIPATING THE STRATUS TO HANG TOUGH. WITH THE COLD ADVECTION
PATTERN DEVELOPING AND CLOUDS AROUND...COOLER TEMPERATURES ARE
LIKELY BOTH TODAY AND TONIGHT. GENERALLY FOLLOWED A CONSENSUS BLEND
FOR HIGHS/LOWS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 258 AM CST SUN FEB 8 2015
HIGHLIGHTS / CONCERNS....
1. PRECIPITATION TUESDAY/TUESDAY NIGHT...AND TYPE.
2. WINDS WEDNESDAY - WEDNESDAY NIGHT
3. ARCTIC COLD SHOT WEDNESDAY NIGHT/THURSDAY WITH ANOTHER ONE
POSSIBLE ON SATURDAY.
SOME OF THE WESTERN U.S. UPPER RIDGING LOOKS TO CROSS THE FORECAST
AREA MONDAY NIGHT IN RESPONSE TO A COLLECTION OF SHORTWAVES MOVING
INTO THE DAKOTAS BY 12Z TUESDAY. THIS UPPER RIDGING COMBINED WITH A
PIECE OF DRIER CANADIAN HIGH PRESSURE MOVING INTO THE FORECAST AREA
ON MONDAY SHOULD HELP TO SCOUR OUT SOME OF THE STRATUS. DESPITE
THE INCREASING SUNSHINE ON MONDAY...925MB TEMPS OF -8 TO -12C WILL
RESULT IN A COOLER DAY COMPARED TO TODAY.
PRECIPITATION CONCERNS CONTINUE FOR TUESDAY INTO TUESDAY NIGHT AS
THE AFOREMENTIONED COLLECTION OF SHORTWAVES MOVE THROUGH THE REGION.
SOME TIMING DIFFERENCES EXIST BETWEEN THE 08.00Z NAM...GFS...
CANADIAN AND ECMWF...BUT THERE IS A STRONG CONSENSUS FOR LOCATIONS
NORTH OF I-90 TO SEE SOME PRECIPITATION. DECENT 285-300K ISENTROPIC
LIFT IS PROGGED...COMBINED WITH THE DPVA FROM THE SHORTWAVES AND
PRECIPITABLE WATER CLIMBING TO OR ABOVE 0.5 INCH ARE ALL FAVORABLE
FOR PRECIPITATION. THUS...HAVE RAISED CHANCES UP SOME NORTH OF I-90.
A WARM LAYER ALOFT WILL NOT IMPACT THE PRECIPITATION TYPE LIKE IT IS
THIS MORNING...HOWEVER...THERE ARE CONCERNS THAT WE COULD LOSE THE
ICE IN THE CLOUDS. THIS SEEMS TO BE MOST PREVALENT SOUTH OF I-90
WHERE CONFIDENCE/AMOUNT OF PRECIPITATION IS LOWER. OVERALL...THIS
TUESDAY/TUESDAY NIGHT PERIOD COULD REQUIRE A WINTER WEATHER ADVISORY
AT SOME POINT. DEFINITELY WORTH MONITORING.
FROM WEDNESDAY AND BEYOND...THE 500MB PATTERN FEATURES RIDGING OVER
MUCH OF WESTERN NORTH AMERICA AND TROUGHING OVER EASTERN NORTH
AMERICA. IN FACT...THE FLOW IS CLOSE TO BECOMING CROSS-POLAR. WHAT
THIS MEANS IS A PATTERN FAVORABLE FOR PERIODIC ARCTIC COLD SHOTS.
THE BIG QUESTION IS HOW FAR WEST WILL THEY BE.
THE FIRST ARCTIC COLD SHOT AFFECTS THE REGION LATE WEDNESDAY INTO
THURSDAY...IN RESPONSE TO A POTENT SHORTWAVE TROUGH DROPPING THROUGH
THE REGION. ITS POSSIBLE SOME LIGHT SNOW COULD PRECEDE THE TROUGH
WEDNESDAY MORNING...PARTICULARLY IN WISCONSIN. OTHERWISE...BRISK
WINDS AND COLD WILL BE THE STORY. 925MB TEMPS PLUMMET TO -18 TO -20C
BY 12Z THU ON A 25-40 KT WIND...SO WIND CHILLS COULD BECOME A FACTOR
THURSDAY MORNING. WITH THE STRONGER WINDS COMING IN HAVE ALSO
INCREASED WIND SPEEDS FOR WEDNESDAY INTO THURSDAY MORNING. COULD SEE
GUSTS 30 KT OR SO IN FAVORED WIND PRONE AREAS. WE GET A BRIEF BREAK
FROM THE COLD ON FRIDAY AS WARM ADVECTION OCCURS AHEAD OF ANOTHER
POTENT SHORTWAVE TROUGH DROPPING DOWN INTO LAKE SUPERIOR. A LITTLE
LIGHT SNOW IS POSSIBLE FROM THIS WARM ADVECTION. THEN...THE ARCTIC
COLD IS LOOKING MORE LIKELY TO RETURN FOR SATURDAY WITH 925MB TEMPS
SIMIALR TO THOSE ON THURSDAY. FOLLOWED A MODEL CONSENSUS FOR HIGHS
ON SATURDAY BUT THESE MAY NEED LOWERING IN FUTURE FORECASTS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1146 PM CST SAT FEB 7 2015
MVFR/IFR FOG CONTINUES TO BE A PROBLEM OVERNIGHT AND MUCH OF SUNDAY.
SFC LOW WAS MOVING SOUTHEAST OF THE AREA LATE THIS EVENING WITH
LIGHT NORTH WINDS STARTING TO SPREAD INTO TAF SITES...FOR SOME
BOUNDARY LAYER STIRRING. THICKER MID/HIGH CLOUDS WERE SPREADING OVER
THE AREA AS WELL. VSBYS IN BR IN THE 2-5SM RANGE LATE THIS EVENING
AND APPEARS THESE VSBYS WILL GENERALLY HOLD THRU THE OVERNIGHT HOURS
AND SUNDAY MORNING. MVFR STRATUS CLOUDS WERE JUST NORTH/EAST OF KLSE
AND WITH SFC-900MB WINDS TO BECOME NORTH-NORTHEAST OVERNIGHT...THESE
CLOUDS LOOKING TO ADVECT INTO THE KLSE/KRST AREAS LATER TONIGHT.
LATEST MODELS HAVE TRENDED DRIER IN THE 850-700MB LAYER SUNDAY...AS
A MID LEVEL SHORTWAVE PASSES. WENT BACK TO A VCSH MENTION AT
KRST/KLSE 15Z-20Z WITH WHAT NOW LOOKS TO BE MORE OF A 20-30 PERCENT
CHANCE OF SOME VERY LIGHT MIXED PRECIP. NORTH-NORTHEAST LOWER LEVEL
WINDS CONTINUE TO ADVECT PLENTY OF 925-850MB MOISTURE OVER THE AREA
SUN AFTERNOON/EVENING...WITH MVFR/LCL IFR CIGS PERSISTING.
HOWEVER...DRIER/COOLER SFC FLOW FROM THE NORTHEAST SHOULD SCOUR OUT
MUCH OF THE BR/HZ THRU THE LATER AFTERNOON/EVENING HOURS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1048 PM MST SAT FEB 7 2015
.UPDATE...
ISSUED AT 611 PM MST SAT FEB 7 2015
WINDS HAVE BEEN QUICK TO DIMINISH AFTER SUNSET...WITH FORECAST
SOUNDINGS FOR MANY LOCATIONS SUGGESTING THE LLVL INVERSION IS
STRENGTHENING RAPIDLY THUS DECOUPLING THE STRONG WINDS ALOFT WITH
THE SURFACE. AS CURRENT OBS ARE PARALLELING FORECAST SOUNDINGS
FAIRLY WELL...FELT JUSTIFIED IN CANCELING THE WARNING EARLY FOR A
FEW LOCATIONS OUTSIDE THE WIND PRONE AREAS OF SOUTHEAST WYOMING
AND LETTING THE WIND ADVISORY EXPIRE ON TIME IN THE PANHANDLE.
LEFT THE WIND PRONE AREAS AND CONVERSE COUNTY IN THE WARNING UNTIL
8 PM AS THESE AREAS COULD STILL SEE SOME RESIDUAL MOUNTAIN WAVE
ACTIVITY BRING GUSTS UP TO 60 MPH OVER THE NEXT COUPLE OF HOURS.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 250 PM MST SAT FEB 7 2015
OBSERVATIONS ACROSS SOUTHEAST WYOMING SHOW THE HIGH WIND EVENT IS
A BIT STRONGER THAN PREVIOUSLY EXPECTED AS WIND GUSTS AROUND
CONVERSE COUNTY...AND PLATTE COUNTY HAVE BEEN AROUND 85 MPH THIS
AFTERNOON. EVEN DOUGLAS HAS SEEN GUSTS JUST UNDER 80 MPH AN HOUR
OR SO AGO. BELIEVE THESE WINDS ARE PARTIALLY DUE TO MOUNTAIN WAVE
ACTIVITY AS WELL AS BL MIXING. CURRENT HIGH WIND WARNINGS LOOK
GOOD AND ARE ON TRACK. ADDED NIOBRARA COUNTY TO THE WARNING WITH
LUSK GUSTING AROUND 60 MPH...AND EVEN STRONGER WINDS EXPECTED
OVER THE NEXT FEW HOURS. RAWLINS AND LARAMIE ARE STRUGGLING TO
REACH CRITERIA THIS AFTERNOON...BUT WILL KEEP THE WARNING OUT FOR
NOW SINCE SUSTAINED WINDS MAY APPROACH THE HOURLY 40 MPH CRITERIA
SHORTLY.
STRONG WESTERLY WINDS WILL SLOWLY DIMINISH THIS EVENING. THE
WARNING IS GOOD FOR 8 PM...BUT MAY NEED TO BE EXTENDED FOR A FEW
ZONES DEPENDING ON TRAVEL IMPACTS. THE HRRR HAS VERIFIED WELL THIS
AFTERNOON...AND SHOWS GUSTS LOWERING BELOW 45 MPH BETWEEN 7 TO 9
PM. HOWEVER...WOULD NOT BE SURPRISED IF WINDS INCREASE FOR A BRIEF
TIME AROUND MIDNIGHT...MAINLY DUE TO AN INCREASING LLVL PRESSURE
GRADIENT.
FOR SUNDAY...UPPER LEVEL RIDGE AXIS IS EXPECTED TO BUILD WEST OF
THE FORECAST AREA. WITH NORTHWEST FLOW ALOFT...TEMPERATURES IN
THE AFTERNOON WILL BE 5 TO 10 DEGREES COOLER THAN TODAY BUT STILL
WELL ABOVE NORMAL FOR THIS TIME OF THE YEAR...WITH HIGHS IN THE
50S TO AROUND 60 IN THE LOWER VALLEYS. IT WILL REMAIN WINDY ACROSS
MUCH OF THE AREA WITH WEST TO NORTHWEST WINDS BETWEEN 20 TO 30 MPH
AND GUSTS AROUND 40 MPH. THESE WINDS WILL CONTINUE TO SUBSIDE
THROUGH THE AFTERNOON AND INTO SUNDAY EVENING.
MODELS SHOW THE UPPER LEVEL RIDGE AXIS MOVING ACROSS THE FORECAST
AREA ON MONDAY AS A PACIFIC STORM SYSTEM MOVES ONSHORE AND ACROSS
THE NORTHERN GREAT BASIN REGION. WINDS WILL INCREASE OUT OF THE
SOUTHWEST DURING THE DAY WEST OF THE LARAMIE RANGE...BUT SHOULD
REMAIN WELL BELOW HIGH WIND CRITERIA. MODELS INDICATE SOME RAIN
AND SNOW MOVING INTO SOUTHERN CARBON AND ALBANY COUNTIES IN THE
EVENING AND DURING MONDAY NIGHT. INCREASED POP UP TO 60 PERCENT
FOR THE MOUNTAINS WHERE A FEW INCHES OF SNOW IS POSSIBLE...BUT
MAINLY EXPECTED RAIN ACROSS THE HIGH VALLEYS.
.LONG TERM...TUESDAY THROUGH SATURDAY...
SEASONABLY WARM AND DRY CONDITIONS ARE LIKELY TO PERSIST THROUGH THE
EXTENDED FORECAST PERIOD. MOUNTAIN SNOW SHOWERS ARE A POSSIBILITY ON
TUE NIGHT AND WED AS A WEAK MIDLVL SHORTWAVE TRAVERSES THE FLOW OVER
THE CENTRAL ROCKIES. H7-H3 MOISTURE PROGS FROM MOST MODELS ARE MOST
FAVORABLE OVER THE HIGHER TERRAIN...SO CHANCES FOR RAIN AND/OR SNOW
WILL BE LOWER OVER THE PLAINS. THERMAL PROFILES WILL BE WARM ENOUGH
FOR RAIN BELOW 8K FEET AGL. GFS/ECMWF ARE IN GOOD AGREEMENT WITH A
SPLIT FLOW PATTERN DEVELOPING BY MID TO LATE WEEK. THIS ESTABLISHES
A REX BLOCK AS A CLOSED LOW DRIFTS WEST OVER NORTHERN MEXICO THROUGH
SAT BENEATH LARGE SCALE UPPER RIDGING. SHORTWAVE ENERGY WILL BE HARD
TO COME BY IN THIS PATTERN...SO EXPECT LITTLE OR NO CHANCES FOR PCPN
INTO THE WEEKEND. H7 TEMPS RANGING FROM -2 TO 0 C WILL KEEP HIGHS IN
THE 45 TO 55 DEGREE RANGE FOR MOST OF THE CWA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1048 PM MST SAT FEB 7 2015
VFR CONDITIONS WILL CONTINUE THROUGH THE PERIOD. WINDS WILL REMAIN
GUSTY ACROSS SOUTHEAST WYOMING AND WESTERN/SOUTHERN PORTIONS OF
THE PANHANDLE TONIGHT...WITH GUSTS OF 25 TO 35 KTS. WIDESPREAD
GUSTY WINDS WILL RETURN TO ALL TERMINALS LATE SUNDAY
MORNING...WITH SPEEDS OF 25 TO 35 KTS EXPECTED IN NEBRASKA AND 30
TO 40 KTS FOR WYOMING. SHOULD SEE A STEADY DECREASE IN WINDS
THROUGH LATE SUNDAY AFTERNOON AND EVENING. MOUNTAIN WAVE
TURBULENCE WILL REMAIN ACTIVE THROUGH THE PERIOD OVER SOUTHEAST
WYOMING.
&&
.FIRE WEATHER...
ISSUED AT 147 PM MST SAT FEB 7 2015
FIRE WEATHER CONCERNS WILL REMAIN ON THE LOW SIDE THIS WEEKEND AND
INTO EARLY NEXT WEEK. VERY STRONG WINDS AND LOW HUMIDITIES WILL
STILL BE A CONCERN ALONG AND EAST OF THE LARAMIE RANGE THIS
AFTERNOON AND INTO THIS EVENING. OTHERWISE...HUMIDITIES WILL TREND
HIGHER ON SUNDAY AND MONDAY WITH SLIGHTLY MORE LOW LEVEL MOISTURE.
TEMPERATURES WILL BECOME COOLER BY THE MIDDLE OF NEXT WEEK AS A
COLD FRONT MOVES ACROSS THE AREA LATE ON TUESDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...RJM
SHORT TERM...TJT
LONG TERM...CLH
AVIATION...RJM
FIRE WEATHER...TJT
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1114 PM EST MON FEB 9 2015
.SYNOPSIS...
A BROAD AREA OF LOW PRESSURE WILL PASS OFF THE CAROLINA COAST
TONIGHT, WITH HIGH PRESSURE BUILDING OVER THE REGION FROM THE
NORTHWEST FOR TUESDAY AND WEDNESDAY. A COLD FRONT WILL CROSS THE
AREA THURSDAY, WITH A STRONG LOW PRESSURE SYSTEM EXPECTED TO DEVELOP
ALONG THIS FRONT AS IT MOVES OFF THE COAST. VERY COLD AIR AND STRONG
WINDS ARE EXPECTED FOR THE MID-ATLANTIC REGION BEHIND THIS FRONT
THURSDAY NIGHT AND FRIDAY. A CLIPPER SYSTEM MAY EFFECT THE AREA ON
SATURDAY, FOLLOWED BY YET ANOTHER BLAST OF COLD AIR ON SUNDAY AND
MONDAY AS ANOTHER CANADIAN HIGH PRESSURE SYSTEM MOVES EAST.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
BASED ON RADAR FOR THE NORTH AND THE LATEST GUIDANCE FOR SOUTH,
ADVISORIES FOR THESE PARTS OF OUR CWA WERE EXTENDED FOR A FEW MORE
HOURS.
A FEW CHANGES WITH THIS UPDATE. A MAJORITY OF THE HI-RES GUIDANCE
HAS NOT BEEN HANDLING THE CURRENT PRECIPITATION ACROSS SEPA TOO
WELL, ALTHOUGH THE HRRR IS THE BETTER OF THE GUIDANCE. USED A
HEAVY BLEND OF CONTINUITY AND HRRR THROUGH TUESDAY MORNING. THE
TRANSITION LINE FROM FZRA TO SNOW IS STILL SITTING ACROSS SEPA
INTO CENTRAL NEW JERSEY BASED ON REGIONAL OBSERVATIONS. THE
FREEZING LAYER WILL CONTINUE TO SAG SOUTH-SOUTHEAST THROUGH THE
OVERNIGHT HOURS AND EVENTUALLY EVERYONE WILL CHANGE OVER TO A
SNOW/SLEET MIX...ALL SNOW NORTH OF THE DELMARVA AFTER MIDNIGHT.
DID NOT TOUCH THE CURRENT ADVISORIES AS MORE PRECIPITATION HAS
BLOSSOMED TO THE WEST OF THE REGION AND THOUGH ACROSS THE POCONOS
AND NORTHERN NEW JERSEY IT SHOULD BE MOSTLY SNOW, WHENEVER WE LOSE
THE INTENSITY OF THE PRECIPITATION THE COLUMN DRIES ENOUGH TO
INCLUDE SOME VERY PATCHY FREEZING DRIZZLE.
ACROSS THE DELMARVA TEMPERATURES HAVE DROPPED TO OR BELOW FREEZING
AND THE THERMAL PROFILE IS SHOWING THE MELTING LAYER AT 850MB
STILL ACROSS THE PHILLY METRO AREA...FREEZING RAIN WILL INCREASE
IN COVERAGE LATE THIS EVENING INTO THE EARLY TUESDAY MORNING HOURS
BEFORE A SNOW/SLEET PHASE CHANGE OCCURS.
LOW TEMPS TONIGHT WILL DROP INTO THE TEENS ACROSS THE FAR
NORTH...AND DROP INTO THE MID/UPPER 20S ELSEWHERE. WINDS WILL BE
MOSTLY N OR NE AT 10 TO 15 MPH OVERNIGHT...HIGHER ALONG THE SHORE
AREAS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
HIGH PRESSURE WELL TO THE NORTH WILL BEGIN TO BUILD TOWARDS THE
AREA. LOW PRESSURE ASSOCIATED WITH THE SYSTEM FROM THE NEAR TERM
WILL BE WELL TO THE SOUTH...BUT WILL BE STRENGTHENING WHILE MOVING
OFFSHORE. THE ONLY PCPN WE HAVE FOR TUESDAY WILL BE FOR THE MORNING
ACROSS THE DELMARVA AND SE NJ WHERE SLGT CHC OR SMALL CHC POPS WILL
BE FOUND. BY MORNING...TEMPS WILL LIKELY BE COLD ENOUGH FOR MOSTLY
LIGHT SNOW. SKY COVER TUESDAY WILL BE MOSTLY CLOUDY FOR THE MOST
PART...BUT SOME IMPROVEMENTS NORTH ARE POSSIBLE LATER TUE. WINDS
WILL BE MODERATE WITH WINDS MOSTLY NORTHERLY 10 TO 15 MPH AND GUSTS
IN THE LOW 20S MPH RANGE. HIGH TEMPS WILL MOSTLY BE IN THE 30S
ACROSS THE REGION.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE MID-LEVEL FLOW PATTERN FROM TUESDAY NIGHT THROUGH MONDAY OF NEXT
WEEK IS FORECAST TO BE PUNCTUATED BY TWO EXTREME TROUGHS...ONE
THURSDAY INTO FRIDAY...THE OTHER LATE SATURDAY THROUGH SUNDAY. SOME
OF THE COLDEST AIR OF THE SEASON...IF NOT THE COLDEST...WILL
INVADE THE NORTHEAST SECTION OF THE COUNTRY IN THEIR WAKE, WITH A
FLOW DIRECTLY FROM THE POLAR REGIONS.
TUESDAY NIGHT SHOULD BE FAIRLY TRANQUIL, WITH LIGHTER WINDS, PERHAPS
SLIGHTLY STRONGER NEAR THE COAST. NO PRECIPITATION IS EXPECTED, WITH
NORMAL TO SLIGHTLY BELOW NORMAL TEMPERATURES AS SURFACE HIGH
PRESSURE BUILDS OVER THE AREA. WEDNESDAY WILL FEATURE MAINLY CLEAR SKIES
FOR A GOOD PART OF THE DAY, BUT SOME HIGH CLOUDS ARE POSSIBLE IN
THE WEST LATE. HIGH TEMPERATURES ON WEDNESDAY WILL BE SEVERAL
DEGREES BELOW NORMAL. LIGHT SNOW IS POSSIBLE IN THE NORTHERN HALF
OF THE CWA WEDNESDAY NIGHT AS A CLIPPER SYSTEM MOVES THROUGH NEW
YORK STATE. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM WILL MOVE
ACROSS THE AREA ON THURSDAY, USHERING IN BITTER COLD AIR FOR
THURSDAY NIGHT AND FRIDAY. THE ASSOCIATED MID-LEVEL TROUGH IS
EXPECTED TO BECOME NEGATIVELY TILTED JUST AS IT SWINGS THROUGH OUR
AREA THURSDAY NIGHT, SO RAPID DEVELOPMENT OF A SURFACE LOW IS
EXPECTED ONCE AGAIN OVER THE NEW ENGLAND MARITIMES.
UNFORTUNATELY...THE GRADIENT GENERATED BY THIS DEPARTING BUT
DEEPENING LOW PRESSURE SYSTEM WILL BRING GUSTY NORTHWEST WINDS TO
OUR AREA...DRIVING WIND CHILL TEMPERATURES DOWN TO THE NEGATIVE
TEENS (AND PERHAPS BEYOND IN THE HIGHER ELEVATIONS UP NORTH) FOR
THURSDAY NIGHT. HIGH TEMPERATURES ON FRIDAY WILL STRUGGLE TO
EMERGE OUT OF THE SINGLE DIGITS IN THE FAR NORTH, AND WON`T GET
OUT OF THE LOW TO MID 20S IN THE SOUTH...SOME TWENTY DEGREES BELOW
NORMAL FOR THIS TIME OF YEAR. ANOTHER COLD NIGHT IS ON TAP FOR
FRIDAY NIGHT, BUT WITH LESS WIND IT MIGHT NOT FEEL QUITE SO
COLD...AND THE HOUSE WILL BE A LITTLE EASIER TO HEAT.
THEN ANOTHER BLAST HEADS OUR WAY ON SATURDAY, HERALDED BY A CLIPPER
SYSTEM WITH SOME LIGHT SNOW FROM WEST TO EAST STARTING IN THE
AFTERNOON. THIS CLIPPER COULD INTENSIFY AS IT MOVES OFF THE COAST
SATURDAY NIGHT, BRINGING GUSTY WINDS BACK TO THE AREA JUST AS COLD
AIR ONCE AGAIN INVADES THE REGION BEHIND A COLD FRONT. TEMPERATURES
SATURDAY NIGHT AND SUNDAY COULD BE COLDER THAN THE MIDWEEK SYSTEM
AND PERHAPS EVEN COLDER SUNDAY NIGHT GOING INTO MONDAY, BUT BY LATE
SUNDAY WINDS SHOULD BE SUBSIDING JUST A BIT.
ALL-IN-ALL, NOT A VERY NICE WEEK AHEAD...UNLESS YOU/RE A POLAR BEAR!
&&
.AVIATION /04Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TONIGHT...MVFR/IFR. AREAS OF FREEZING RAIN/SNOW/SLEET ACROSS THE
REGION TONIGHT. AT THIS POINT RDG/ABE SHOULD SEE THE MOST SNOW,
THOUGH ONLY A LIGHT ACCUMULATION, WITH TIMES OF SLEET MIXING IN
THROUGH THE REMAINDER OF THE EVENING. THERE COULD BE A PERIOD LATE
TONIGHT WHERE SOME PATCHY FREEZING DRIZZLE OCCURS. ELSEWHERE
FREEZING RAIN WILL BE THE MAIN PRECIPITATION THROUGH THE EVENING
BEFORE CHANGING OVER TO A SNOW/SLEET MIX AFTER MIDNIGHT. NORTHEAST
WINDS AROUND 10 TO 15 KNOTS MAY BECOME GUSTY AT TIMES.
TUESDAY...MVFR TO POCKETS OF IFR CONDITIONS ARE EXPECTED EARLY
TUESDAY MORNING AS ANY REMAINING LIGHT SNOW WILL BE ENDING FROM WEST
TO EAST. LIGHT SNOW SHOULD TAPER OFF FIRST DURING THE EARLY MORNING
FOR THE WESTERN SITES, INCLUDING KRDG/KABE, AND THEN WITHIN A COUPLE
OF HOURS EITHER SIDE OF DAYBREAK ACROSS THE DELAWARE VALLEY AND THEN
ACROSS NJ. MVFR CONDITIONS WILL LIKELY HOLD THROUGH THE MORNING,
BEFORE TRANSITIONING TO VFR INTO THE AFTERNOON. NORTH-NORTHEAST TO
NORTHERLY WINDS ARE ANTICIPATED THROUGH THE DAYTIME, WITH GUSTS
AROUND 20 KNOTS EXPECTED.
OUTLOOK...
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...MAINLY VFR WITH SUBSIDING
WINDS.
THURSDAY...MAINLY VFR. HOWEVER, THERE IS A CHANCE OF LIGHT SNOW WHICH
COULD BRIEFLY REDUCE CONDITIONS INTO THE MVFR OR IFR CATEGORY.
THURSDAY NIGHT THROUGH FRIDAY NIGHT FRIDAY...MAINLY VFR.
SATURDAY...A CHANCE OF LIGHT SNOW COULD ONCE AGAIN REDUCE CONDITIONS
IN THE THE MVFR OR IFR CATEGORY.
&&
.MARINE...
HIGH PRESSURE WELL TO THE NORTH WILL MOVE TOWARDS THE AREA LATE
TONIGHT. MEANWHILE...LOW PRESSURE WILL MOVE OFFSHORE (VA/NC) THEN
DEEPEN WHILE MOVING NE. THE PRESSURE GRADIENT WILL BEGIN TO
STRENGTHEN ACROSS THE AREA WITH WINDS/SEAS BUILDING. SCA FLAGS
WILL REMAIN FOR DEL BAY. THE GALE FLAG FOR THE NRN WATERS
CONTINUES THRU 23Z TUE...WHILE THE DEL BAY AND SRN COASTAL WATERS
HAS THE FLAGS THRU 03Z WED. THESE ENDING TIMES ARE OK FOR NOW.
OUTLOOK...
TUESDAY NIGHT...A GALE WARNING IS IN EFFECT UNTIL 1000 PM ON OUR
OCEAN WATERS SOUTH OF GREAT EGG INLET, NEW JERSEY. OTHERWISE, SMALL
CRAFT ADVISORY CONDITIONS SHOULD CONTINUE IN OUR MARINE AREA.
WEDNESDAY...SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED ON OUR
OCEAN WATERS.
WEDNESDAY NIGHT AND THURSDAY MORNING...WAVE HEIGHTS ON OUR OCEAN
WATERS MAY REMAIN NEAR 5 FEET. WIND SPEEDS ARE FORECAST TO STAY
BELOW THE SMALL CRAFT ADVISORY CRITERION.
THURSDAY AFTERNOON...SMALL CRAFT ADVISORY CONDITIONS ARE
ANTICIPATED TO RETURN WITH A DEVELOPING NORTHWEST WIND.
THURSDAY NIGHT AND FRIDAY...NORTHWESTERLY GALE FORCE GUSTS ARE
EXPECTED.
FRIDAY NIGHT...SMALL CRAFT ADVISORY WINDS EXPECTED.
SATURDAY...NO HEADLINES EXPECTED ATTM.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY UNTIL 4 AM EST TUESDAY FOR PAZ054-055-
061-062-105.
WINTER WEATHER ADVISORY UNTIL 6 AM EST TUESDAY FOR PAZ060-070-
071-101>104-106.
NJ...WINTER WEATHER ADVISORY UNTIL 4 AM EST TUESDAY FOR NJZ001-
007>010.
WINTER WEATHER ADVISORY UNTIL 6 AM EST TUESDAY FOR NJZ012>022-
025>027.
WINTER WEATHER ADVISORY UNTIL 10 AM EST TUESDAY FOR NJZ023-024.
DE...WINTER WEATHER ADVISORY UNTIL 6 AM EST TUESDAY FOR DEZ001.
WINTER WEATHER ADVISORY UNTIL 10 AM EST TUESDAY FOR DEZ002>004.
MD...WINTER WEATHER ADVISORY UNTIL 6 AM EST TUESDAY FOR MDZ008.
WINTER WEATHER ADVISORY UNTIL 10 AM EST TUESDAY FOR MDZ012-015-
019-020.
MARINE...GALE WARNING UNTIL 10 PM EST TUESDAY FOR ANZ452>455.
GALE WARNING UNTIL 6 PM EST TUESDAY FOR ANZ450-451.
SMALL CRAFT ADVISORY UNTIL 10 PM EST TUESDAY FOR ANZ430-431.
&&
$$
SYNOPSIS...MIKETTA
NEAR TERM...HEAVENER/O`HARA
SHORT TERM...O`HARA
LONG TERM...MIKETTA
AVIATION...HEAVENER/KLINE/MIKETTA
MARINE...MIKETTA/O`HARA
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1220 AM EST TUE FEB 10 2015
.SYNOPSIS...
A COLD FRONT WILL CONTINUE PUSHING EAST TONIGHT BRINGING SHOWERS
TO THE AREA. FAIR WEATHER EXPECTED TUESDAY AND WEDNESDAY WITH
GENERALLY SEASONAL TEMPERATURES. A DRY COLD FRONT WILL MOVE
THROUGH THURSDAY...FOLLOWED BY MUCH COLDER CONDITIONS FRIDAY
THROUGH THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AN UPPER TROUGH TO OUR WEST WILL CONTINUE TO PROMOTE A CHANCE OF
SHOWERS OVERNIGHT AS IT SWINGS EAST. THE COLD FRONT IS LOCATED
ALONG THE WESTERN PART OF THE FORECAST AREA AND WILL CONTINUE TO
CROSS THE REGION TONIGHT. MAIN BAND OF RAINFALL AHEAD OF THE
FRONT HAS SHIFTED OFF THE COAST. REGIONAL RADAR IMAGERY
SHOWS SCATTERED SHOWERS IN THE UPSTATE WHICH ARE NOW MOVING INTO
THE CSRA AND WESTERN MIDLANDS. HRRR MODEL KEEPS LIGHT RAIN IN
THE NORTHERN MIDLANDS INTO TUESDAY MORNING. TEMPERATURES DROPPED
AS THE RAIN MOVED THROUGH EARLIER AND HAVE REMAINED RATHER STEADY.
LOOKING UPSTREAM...THE COLD SURGE OF AIR HAS BEEN LAGGING...SO
EXPECT OVERNIGHT LOWS TO BE MILD...IN THE 40S. WINDS WILL INCREASE
OVERNIGHT AS THE PRESSURE GRADIENT TIGHTENS AND COLD AIR ADVECTION
INCREASES. WINDS WILL INCREASE TO AROUND 10 TO 15 KNOTS WITH GUSTS
AROUND 20 TO 25 KNOTS BY 12Z. AREAS OF FOG HAVE DEVELOPED BUT
EXPECT IMPROVEMENT WITH THE NEXT BATCH OF SHOWERS AND AS WINDS
PICK UP AFTER 06Z.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/...
TUESDAY WILL START OFF MOSTLY CLOUDY...THEN AS DRIER AIR FINALLY
BEGINS WORKING ITS WAY INTO THE REGION BEHIND THE COLD FRONT SKIES
WILL BEGIN CLEARING BY THE AFTERNOON. WINDS WILL BECOME GUSTY
THROUGH THE DAY BEHIND THE FRONT DUE TO A RATHER STRONG PRESSURE
GRADIENT ACROSS THE REGION. WINDS GENERALLY OUT OF THE NORTH
BETWEEN 10 AND 15 MPH...WITH GUSTS AROUND 20 MPH BEING POSSIBLE.
DO NOT EXPECT LAKE WIND ADVISORY CRITERIA TO BE MET AT THIS
TIME...SO DO NOT ANTICIPATE ANY PRODUCT ISSUANCES. WINDS WILL
DIMINISH BY SUNSET. TEMPERATURES MAY BE ABLE TO CLIMB INTO THE
MIDDLE TO POSSIBLY UPPER 50S DURING THE AFTERNOON DEPENDING ON HOW
MUCH SUN THE REGION GETS.
DRY WEATHER IS EXPECTED TO CONTINUE FOR THE REMAINDER OF THE SHORT
TERM. THERE WILL BE ANOTHER FRONTAL PASSAGE ON THURSDAY...WHICH
WILL BRING INCREASING WINDS BACK TO THE REGION. WEDNESDAY AND
THURSDAY WILL STILL BE GENERALLY IN THE 50S FOR HIGHS...AND
OVERNIGHT LOWS IN THE 30S FOR TUESDAY NIGHT...THEN MODERATING INTO
THE 40S FOR WEDNESDAY NIGHT. THE COLDEST NIGHT WILL BE THURSDAY
NIGHT BEHIND THE COLD FRONT...WITH READINGS BACK DOWN INTO THE 20S
BECOMING POSSIBLE.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
THE DRY AIR WILL CONTINUE ACROSS THE REGION THROUGH THE WEEKEND.
BELOW NORMAL TEMPERATURES WILL ALSO CONTINUE. BIGGEST QUESTION
MARK IN REGARDS TO TEMPERATURES APPEARS TO BE OVER THE WEEKEND.
LARGE STANDARD DEVIATIONS IN THE MODEL GUIDANCE FOR BOTH MAX/MIN
READINGS. THIS IS DUE TO A POSSIBLE ARCTIC INTRUSION OF AIR
SATURDAY NIGHT INTO MONDAY. THE GFS/ECMWF/CMC SHOW STRONG AREA OF
HIGH PRESSURE MOVING INTO THE REGION SUNDAY AND MONDAY...WITH A
STRONG LOW MOVING OFF THE NEW ENGLAND COAST. IN GENERAL HAVE GONE
SLIGHTLY BELOW THE MODEL AVERAGES FOR TEMPERATURES SATURDAY NIGHT
THROUGH MONDAY...BUT DID NOT GO WITH THE EXTREME VALUES. THERE IS
SOME BITTERLY COLD AIR CURRENTLY ACROSS NORTH-CENTRAL AND WESTERN
CANADA...AND EASTERN ALASKA. WOULD PREFER TO WAIT AND SEE HOW MUCH
OF THIS AIR GETS PUSHED SOUTHWARD...ALONG WITH WHAT DIRECTION IT
HEADS...WITH THE POSSIBLE SURGE NEXT WEEKEND BEFORE GOING ON THE
EXTREME SIDE OF ANY GUIDANCE.
&&
.AVIATION /05Z TUESDAY THROUGH SATURDAY/...
WIDESPREAD IFR/LIFR CIGS/VSBYS DUE TO FOG AND LOW STRATUS IN THE
CAE/CUB/OGB TERMINALS EARLY THIS MORNING...WITH VFR VSBYS/IFR CIGS
AT AGS/DNL. RADAR INDICATING SCATTERED SHOWERS IN THE UPSTATE SOUTH
CAROLINA MOVING SOUTHEAST TOWARD THE REGION. THESE SHOWERS WILL MOVE
INTO THE AREA MAINLY BETWEEN 06Z-09Z AND EXPECT SOME IMPROVEMENT TO
VISIBILITIES AND CEILINGS DURING THIS PERIOD. MAINLY MVFR FORECAST
AFTER 09Z...ALTHOUGH LOW STRATUS STILL POSSIBLE.
NORTH WINDS EXPECTED TO INCREASE AFTER 10Z WITH GUSTS TO NEAR 20
KNOTS. UPPER LEVEL TROUGH AXIS OVER THE AREA EARLY THIS MORNING AND
AND ALONG COAST LATER TODAY. MODELS INDICATE CONSIDERABLE LOW-LEVEL
MOISTURE ACROSS REGION THROUGH THIS MORNING WITH DRIER AIR ADVECTING
IN DURING THE AFTERNOON. THEREFORE...LOW CEILINGS...MVFR LIKELY TO
CONTINUE THROUGH THE MORNING WITH IMPROVEMENT TO VFR AROUND 18Z WITH
BROKEN STRATO-CU DECK. GUSTY NORTH WINDS TO CONTINUE THROUGH THE DAY
GUSTS TO ABOVE 20 KNOTS POSSIBLE.
EXTENDED AVIATION OUTLOOK...GUSTY WINDS MAY BE POSSIBLE AGAIN ON
THURSDAY BEHIND EXITING COLD FRONTS. CEILINGS AND VISIBILITIES
EXPECTED TO REMAIN VFR THROUGH THE EXTENDED PERIOD DUE TO A DRY
AIR MASS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1151 PM CST MON FEB 9 2015
...UPDATED AVIATION DISCUSSION...
.SHORT TERM /TONIGHT/...
ISSUED AT 328 PM CST MON FEB 9 2015
MAIN CONCERNS ARE CLOUD COVER AND APPROACHING WAVE FROM THE WEST.
LOW STRATUS ERODING OVER THE NORTH MOMENTARILY BUT SHOULD BEGIN TO
FILL BACK IN AFTER SUNSET. THE HRRR SHOWS THE CURRENT SETUP QUITE
WELL WITH SOME THINNING OF THE CLOUD DECK OVER THE NORTH FOLLOWED
BY CLOUDS FILLING IN ONCE AGAIN. THE UPSTREAM SHORT WAVE OVER MT
WILL MOVE SOUTHEAST OVERNIGHT AND SHOULD BEGIN TO IMPACT THE
NORTHWEST WITH PRECIPITATION CHANCES BETWEEN 09-12Z. BUFR
SOUNDINGS OVER THE NORTHWEST SHOW LOWER LAYERS THICKENING TOWARD
MORNING WITH SOME LIFT INCREASING TOWARD 12Z. WILL MAINTAIN LIGHT
FREEZING DRIZZLE ACROSS THE NORTHWEST TRANSITIONING TO A CHANCE
FOR LIGHT FREEZING DRIZZLE OR LIGHT FREEZING RAIN/ICE PELLET MIX
BY 12Z. INITIALLY THERE IS NOT MUCH IN THE WAY OF ICE INTRODUCTION
WHICH WOULD FAVOR SOME LIGHT FREEZING DRIZZLE. TEMPERATURES
TONIGHT ARE CHALLENGING AS WELL. GUIDANCE DROPS VALUES INTO THE
TEENS NORTH TO LOWER TO MID 20S MOST AREAS. LAST NIGHT MOIST
BOUNDARY LAYER AND CLOUD COVER KEPT MINS IN THE LOWER 30S. THOUGH
NOT EXPECTING IT TO BE THAT WARM TONIGHT THERE SHOULD BE A DECENT
GRADIENT FROM EAST TO SOUTHWEST WITH UPPER TEENS EAST TO THE MID
TO UPPER 20S OVER THE SOUTHWEST WHERE CLOUDS WILL HOLD.
.LONG TERM /TUESDAY THROUGH MONDAY/...
ISSUED AT 328 PM CST MON FEB 9 2015
LITTLE HAS CHANGED IN OVERALL FORECAST THINKING FROM PREVIOUS
SHIFTS. A LOW PRESSURE SYSTEM WILL SPREAD PRECIPITATION ACROSS
MOST OF MINNESOTA ON TUESDAY...WITH LIGHT PRECIPITATION AFFECTING
NORTHERN IOWA...THEN PUSH A PRETTY STRONG COLD FRONT ACROSS IOWA
ON TUESDAY NIGHT AND WEDNESDAY MORNING. THE PRECIPITATION ACROSS
NORTHERN IOWA STILL LOOKS SPOTTY AND VERY LIGHT...WITH FORECAST
SOUNDINGS SHOWING CLOUD DEPTHS WAVERING BETWEEN ABOUT 3000 AND
8000 FEET AND MAINLY LOCATED BENEATH BOTH THE ICE INTRODUCTION
LAYER AND THE LIMITED FORCING ASSOCIATED WITH THE LOW PASSING BY
TO THE NORTH. THIS SUPPORTS MOSTLY A DRIZZLE/LIGHT RAIN SCENARIO
WITH TEMPERATURES NEAR OR A LITTLE BELOW FREEZING...LIKELY LEADING
TO SOME LIGHT ICE ACCUMULATIONS OF PERHAPS A FEW HUNDREDTHS OF AN
INCH. GIVEN THE RELATIVELY LOW CONFIDENCE IN ACCUMULATING
PRECIPITATION OCCURRING IN OUR AREA...WITH ONLY 40 TO 50 POPS IN
THE NORTH AND VERY LIGHT EXPECTED AMOUNTS...HAVE NOT ISSUED AN
ADVISORY AT THIS TIME. HOWEVER...THIS WILL BE CLOSELY MONITORED
TONIGHT AND TOMORROW AND ONE MAY YET BECOME WARRANTED IF THERE IS
A MORE CONSISTENT SIGNAL FOR MEANINGFUL ICE ACCUMULATION/IMPACTS.
THE LIGHT PRECIPITATION ACROSS THE NORTH WILL END ON TUESDAY
NIGHT...THEN THE AFOREMENTIONED COLD FRONT WILL SWEEP RAPIDLY
SOUTHEASTWARD ACROSS THE AREA. WINDS WILL SURGE SIGNIFICANTLY ON
WEDNESDAY MORNING...THEN AGAIN ON WEDNESDAY EVENING AS ONE LAST
500 MB IMPULSE ROUNDS THE TROUGH AND IS REFLECTED BY A TIGHTENING
SURFACE PRESSURE GRADIENT. FORECAST SOUNDINGS INDICATE WINDS AT
THE TOP OF THE MIXED LAYER APPROACHING 40 KNOTS AT TIMES AND THERE
IS AN INCREASING POSSIBILITY...ESPECIALLY GIVEN THE COLD AIR
ADVECTION AND EFFICIENT MIXING EXPECTED...THAT A WIND ADVISORY MAY
BECOME NECESSARY AT SOME POINT FOR WEDNESDAY INTO WEDNESDAY NIGHT.
TEMPERATURES WILL LIKELY REMAIN STEADY OR FALL DURING THE DAY
WEDNESDAY...THEN PLUMMET FURTHER WEDNESDAY NIGHT WITH WIND CHILLS
OF AROUND 20 TO 25 BELOW FORECAST ACROSS NORTHERN IOWA BY THURSDAY
MORNING.
AS A SURFACE HIGH PRESSURE AREA CROSSES IOWA ON THURSDAY WINDS
WILL LIGHTEN SUBSTANTIALLY BUT IT WILL REMAIN COLD...THEN WE WILL
CONTINUE THIS SERIES OF ALTERNATING HIGHS AND LOW PRESSURE TROUGHS
THROUGH THE WEEKEND. THIS WILL RESULT IN A MODEST WARM UP ON
FRIDAY...ANOTHER FRONTAL PASSAGE LATE FRIDAY...MORE STRONG WINDS
AROUND FRIDAY NIGHT INTO SATURDAY...MORE COLD ON SATURDAY AND
SATURDAY NIGHT...ETC. IN A REPEAT OF THE PATTERN WE HAVE SEEN FOR
THE LAST SEVERAL DAYS ALREADY. THERE IS SOME INDICATION IN THE
PAST SEVERAL RUNS OF THE ECMWF AND GFS THAT THIS PATTERN COULD
SHIFT A BIT FURTHER SOUTHWARD AROUND MONDAY OR TUESDAY OF NEXT
WEEK AS A BROAD 500 MB TROUGH DIGS A BIT FURTHER DOWN INTO THE
CENTRAL U.S. IF THIS VERIFIES THEN IT WOULD SPREAD THE BULK OF THE
PRECIPITATION FROM THE ASSOCIATED SURFACE SYSTEM MORE ACROSS IOWA
RATHER THAN FURTHER NORTH AS WE HAVE SEEN THUS FAR...HOWEVER AT
THIS RANGE IT IS WAY TOO EARLY TO GET MUCH DETAIL OUT OF WHAT THIS
WOULD MEAN FOR SENSIBLE WEATHER AND PRECIPITATION AMOUNTS ACROSS
CENTRAL IOWA.
&&
.AVIATION...10/06Z
ISSUED AT 1150 PM CST MON FEB 9 2015
HIGHER CONFIDENCE WITH FOD/MCW RECEIVING SOME LIGHT FZRA/FZDZ BY
SUNRISE TUESDAY MORNING AND SHOULD NOT LAST PAST 18Z. THE LATEST
HRRR HAS A GOOD HANDLE ON CURRENT RADAR TRENDS AND HAS THE LIGHT
PRECIP MOVING ACROSS NORTHERN IOWA B/T 12-17Z. THE MVFR STRATUS
DECK LOOKS TO PERSIST OVER MCW/FOD/DSM THROUGH TOMORROW NIGHT AND
EVEN INTO WEDNESDAY MORNING. FOR ALO/OTM...CLEARING HAS ALLOWED
FOR SOME PATCHY FOG TO DEVELOP AND SATELLITE TRENDS SHOW THE
STRATUS DECK ERODING JUST SLIGHTLY BACK WESTWARD.
HOWEVER...EXPECTING THE STRATUS TO FILL BACK IN FURTHER EAST WITH
THE SHORTWAVE COMING ACROSS THE STATE BY 09Z. BUT BEFORE
THEN...HAVE MVFR FOG AT OTM AND ALO MENTIONED.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...REV
LONG TERM...LEE
AVIATION...PODRAZIK
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1142 PM CST Mon Feb 9 2015
...Update to aviation forecast discussion and fog forecast...
.UPDATE...
Issued at 825 PM CST MON FEB 9 2015
Surge of dry air has managed to make it into the Cloud/Republic
county areas, so will cancel the dense fog advisory at this time.
There is a small chance for redevelopment of fog within the clear
sky area, but confidence in redevelopment is very low at this
time.
&&
.SHORT TERM...(This Evening through Tuesday)
Issued at 343 PM CST MON FEB 9 2015
Surface high pressure ridge extends southeast across eastern Kansas
from Minnesota. Cool east to northeast flow along with stratus which
has held on most of the day, has kept temperatures from rising much
from morning lows especially across north central Kansas.
Latest visible satellite loop shows the stratus breaking up from
central Missouri into east central Kansas. HRRR, NAM and RAP show
some semblance of this trend for partial clearing from Emporia to
Topeka along with some further clearing this evening into northeast
Kansas. Areas of north central Kansas look to stay in the stratus
tonight. The low clouds may reform later tonight across the east.
Areas of fog are likely for much of the area overnight. Lows tonight
will vary due to breaks in the clouds. Expecting lows in the upper
20s to low to mid 30s.
Thermal axis noses into northeast Kansas on Tuesday ahead of the
next shortwave and surface frontal boundary. Forecast soundings show
mixing to 925mb to 900mb in the afternoon. Stratus looks to break up
in the late morning and early afternoon hours. Highs will range from
the 50s to around 60.
.LONG TERM...(Tuesday Night through Monday)
Issued at 343 PM CST MON FEB 9 2015
Next cold front still on track to move through the county warning
area (cwa) Tuesday night as a weak shortwave trough extending from
the Great Lakes into the southwest CONUS moves through and shears
with time. The initial push of cooler air will lower highs into the
upper 30s and lower 40s for Wednesdays and should move through the
area dry as well.
As the stronger secondary d cold front moves through late
Wednesday/Wednesday night...a much colder push of air will
overspread the area. The GFS is deeper with the eastern trough and
colder than the EC. Following lows in the teens and lower 20s
Thursday morning...highs will struggle to reach the 20s and lower
30s most areas. Again...with only weak forcing and limited
moisture...will maintain a dry fcst.
The upper ridging along the west coast will amplify and edge
eastward by Friday with warmer air temporarily advecting into the
cwa with highs into the 40s east and the low to mid 50s west. Models
are in agreement with the next strong northwest flow wave into the
eastern CONUS trough which will drive another push colder air back
into the cwa with highs mainly in the 30s Saturday...then the low to
mid 40s Sunday.
Even warmer air will then overspread the area on Monday with highs
mainly in the low to middle 50s as another longer wave trough
approaches the central plains. There will be a chance for rain
across the southeast cwa during the day...then a chance for rain or
snow that night as the cold front moves through.
&&
.AVIATION...(For the 06Z TAFs through 06Z Tuesday Night)
Issued at 1134 PM CST MON FEB 9 2015
Difficult period of aviation forecast continues. Now seeing
westward progression of the stratus deck toward TAF sites with
expected arrival at TOP/FOE 08-09Z. Cigs would likely be 1100 to
1500 feet, but with some potential to be IFR. Greater uncertainty
in this stratus reaching MHK, but believe it will around roughly
11Z and also with potential for lower cigs than forecast, and have
a good chance of MVFR vis for several hours at MHK. Question then
becomes when clouds scatter, and this seems likely by mid morning
as stratus will be quite thin.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY until 9 AM CST Tuesday FOR KSZ008-020.
&&
$$
UPDATE...Barjenbruch
SHORT TERM...53
LONG TERM...63
AVIATION...Barjenbruch
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1251 AM EST Tue Feb 10 2015
...Forecast Update...
Issued at 1250 AM EST Tue Feb 10 2015
Light precip continues over our east and south, as the top of the
cloud layer is just at the right temperature to allow a few snow
crystals/grains to form. RUC and NAM time height sections indicate
some thinning of these clouds from the top as subsidence dries the
air from aloft. Thus expect the flurries to end over the next few
hours from north to south. Have updated the forecast for this
adjustment.
Issued at 804 PM EST Mon Feb 9 2015
Have updated the forecast this evening to put in some light drizzle
and/or flurries for the next few hours. Despite drier near-surface
air working in, there has been enough lingering low-level moisture
to squeeze out some light drizzle and/or flurries this evening.
Latest IR-satellite imagery pegs cloud tops at -9 to -11C over most
of the area, so think as surface temperatures fall below freezing,
we should see more flurries than freezing drizzle given ice nuclei
likely to be present in the clouds. Either way, should not cause
many issues and shouldn`t last too long given the drier air working
in. Updated products out shortly.
.SHORT TERM (Now through Tuesday Night)...
Issued at 300 PM EST Mon Feb 9 2015
A 500mb trough will move east of Kentucky this afternoon. In its
wake northerly flow will ensure continued coolish temperatures
through tomorrow.
Extensive low strato-cu currently extends north all the way to
southern Michigan. Forecast soundings and low level relative
humidity progs show low cloudiness continuing all the way through
much of the morning hours Tuesday. North winds of 12 to 15 kts this
afternoon will slowly diminish this evening and remain from the
north at 5 to 10 mph through the morning hours. Winds will become
light and variable Tuesday night as a surface ridge axis passes over
the Commonwealth.
Temperatures tonight will fall into the mid 20s, with highs Tuesday
rising into the upper 30s to the lower 40s. Skies will clear
tomorrow afternoon and stay clear to partly cloudy through Wednesday
morning. Lows will fall into the lower to mid 20s early Wednesday.
.LONG TERM (Wednesday through Monday)...
Issued at 233 PM EST Mon Feb 9 2015
Low pressure crossing the Great Lakes will drag a cold front through
southern Indiana/central Kentucky Wednesday. The front itself will
likely be dry, however it will usher in very cold air with high
pressure that will have had its beginnings over the Yukon. Though
moisture will be shallow behind the front, it shouldn`t be too
difficult to squeeze some snowflakes out in the cold air Wednesday
night and Thursday, especially given the strong upper trof digging
in. Anything that does fall will be very light. The best chances
will be in the Blue Grass, including the Lexington metro, where Lake
Michigan influence will be greatest.
Temperatures Wednesday will be highly dependent on when exactly the
front passes through the region. For now will stay consistent with
recent forecasts and shoot for low to mid 50s. Wednesday night
we`ll drop into the 20s...maybe upper teens in southern Indiana west
of I-65. Thursday will see highs only in the 20s, with brisk
northwest winds gusting to around 20mph, and wind chills of 5 to 15
degrees.
The next cold front will approach Friday and pass through the area
Friday night. The great majority of the precipitation associated
with this system will remain to our north as the front`s parent low
crosses the Great Lakes.
It will then be deja vu all over again as the cold front ushers in
another high from northern Canada. Post-frontal flurries or light
snow showers will be possible Saturday and Saturday night,
especially in the Blue Grass. The real story, however, will be the
cold. After mid-day highs in the 20s on Saturday, temperatures will
begin to fall in the afternoon. Brisk west breezes in the morning
will become frigid northwest winds in the afternoon with gusts to
25, maybe 30, miles per hour. Wind chills will be in the single
digits during the day. Then Saturday night the mercury will drop
into the single digits with wind chills from five below to ten below
zero. Sunday will see highs in the 20s, and then on Monday we may
be able to rebound to around 40 as we get into some return flow.
&&
.AVIATION (06Z TAF Update)...
Issued at 1225 AM EST Tue Feb 10 2015
Light snow continues to affect the LEX terminal this hour. Latest
RUC and NAM time height sections indicate the cloud tops should
start to warm, effectively shutting off the crystals for the light
snow. As cloud tops warm, cigs should stay in the low-end MVFR
range, likely through daybreak. We should start to see some erosion
of those clouds by late morning, with all of the sites likely
becoming VFR by afternoon. Winds will stay northerly the rest of the
morning hours, but will shift to northeasterly during the day as
high pressure moves by to our north.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Updates........KD/RJS
Short Term.....JSD
Long Term......13
Aviation.......RJS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
357 AM EST TUE FEB 10 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 348 PM EST MON FEB 9 2015
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A NW FLOW ALOFT
OVER THE GREAT LKS BTWN AN UPR RDG OVER THE WRN PLAINS AND A TROF
ACROSS THE ERN CONUS. A SHRTWV EMBEDDED IN THIS NW FLOW AND
ACCOMPANYING AREA OF SOMEWHAT DEEPER MSTR/DYNAMIC FORCING THAT
LIFTED INVRN BASE UP TO ARND 4K FT AGL BROUGHT AN UPTICK THIS MRNG
TO THE LES IN THE PRESENCE OF INVRN BASE TEMPS ARND -12C OVER MAINLY
THE NCNTRL WHERE OBSVD N WINDS UPSLOPE. BUT DNVA/SUBSIDENCE IN THE
WAKE OF THE SHRTWV PASSAGE AND IN ADVANCE OF APRCHG SHRTWV RDG HAVE
CAUSED THE LES TO DIMINISH THIS AFTN...AND EVEN FOR THE LO CLDS TO
BREAK UP TO A CERTAIN EXTENT. SINCE THE 12Z INL/YPL ROABS TO THE NW
SHOW MSTR EXTENDING UP THRU ABOUT H7...PLENTY OF CLD COVER AND SOME
FLURRIES LINGER UPSTREAM IN NRN MN AND NW ONTARIO. LOOKING FARTHER
UPSTREAM...A FAIRLY VIGOROUS SHRTWV IS MOVING INTO THE PAC NW AND
OVER THE WRN RDG.
LATE TODAY/TNGT...ALTHOUGH THE LLVLS WL REMAIN COLD ENUF FOR LES...
LARGE SCALE SUBSIDENCE IN ADVANCE OF APRCHG SHRTWV RDG THAT DEPRESS
INVRN BASE TOWARD 2-3K FT WL LIMIT LES INTENSITY AND COVERAGE.
INITIALLY...LLVL LIGHT WINDS ARE FCST TO BACK TOWARD THE NW INTO
THIS EVNG AHEAD OF THE INCOMING SFC RDG. SO MOST OF THE LINGERING
LES/LK CLDS SHOULD BE TO THE E OF MQT AND OVER THE KEWEENAW THIS
EVNG. LIGHT WINDS ASSOCIATED WITH THE PASSING SFC RDG AXIS MAY ALLOW
FOR A MESOLO PRES TO DVLP. HOWEVER...PRESENCE OF A GOOD DEAL OF ICE
NEAR LK SUP E OF MARQUETTE WL LIMIT THE POTENTIAL IMPACT OF THIS
FEATURE IN THESE AREAS. AS THE WINDS TEND TO SHIFT BACK TO THE NE
LATER FOLLOWING THE PASSAGE OF THE RDG AXIS TO THE E...SOME LES
MIGHT SHIFT BACK TOWARD MARQUETTE. ANOTHER WEAK SHRTWV/AREA OF DEEP
LYR QVECTOR CNVGC IS FCST TO MOVE BY LATE TNGT. BUT SINCE SFC RDG
AXIS WL BE PASSING THRU AT THAT TIME...THE IMPACT SHOULD BE MINIMAL.
EXPECT THE LOWEST MIN TEMPS OVER THE E AND SCNTRL WHERE LIGHT E
WINDS WL DRAIN OFF SOME VERY COLD OVER ONTARIO AND MSTR/CLDS TO THE
NW WL HAVE A HARDER TIME REACHING.
TUE...LARGE SCALE WAA/DEEP LYR QVECTOR CNVGC/UPR DVGC IN INCRSG SSE
FLOW BTWN DEPARTING SFC HI PRES RDG TO THE E AND IN ADVANCE OF
SHRTWV NOW OVER THE PAC NW THAT WL BE MOVING THRU THE NRN PLAINS IS
FCST TO ARRIVE IN THE AFTN. THE ARRIVAL OF THIS FORCING AND
ACCOMPANYING UVV WL ALLOW FOR THICKENING CLDS AND SOME SN TO PUSH
INTO THE WRN COUNTIES DURING THE AFTN. H7 SPECIFIC HUMIDITY FCST UP
TO 3 G/KG UNDER THE AXIS OF WAA INDICATES A FEW INCHES OF SN MAY
ACCUMULATE OVER THE FAR W BY 00Z DESPITE A RATHER HI...NARROW DGZ.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 357 AM EST TUE FEB 10 2015
MUCH OF THE FOCUS OF THE LONG TERM PERIOD WILL BE TIED TO THE COLD
AIR MOVING SOUTHEAST ACROSS THE REGION ON WEDNESDAY...LEADING TO
MODERATE LAKE EFFECT SNOW UNDER GUSTY NORTHERLY WINDS WEDNESDAY
NIGHT INTO THURSDAY. HIGH PRESSURE WILL QUICKLY DROP SOUTHEAST
ACROSS THE UPPER GREAT LAKES REGION THURSDAY NIGHT...BEFORE ANOTHER
CLIPPER AND STRONG SHORTWAVE DIVES SOUTHEAST ACROSS THE AREA FRIDAY
AND FRIDAY EVENING. THIS WILL USHER IN EVEN COLDER AIR OVER THE
REGION...PRODUCING ANOTHER PERIOD OF LAKE EFFECT AND GUSTY
NORTHERLY WINDS. THE SHRINKING SNOWFLAKE SIZE WILL BE EFFECTIVE AT
REDUCING VISIBILITIES WEDNESDAY NIGHT INTO THURSDAY...AND AGAIN
FRIDAY NIGHT INTO SATURDAY...LEADING TO VERY LOW VISIBILITIES IN
THE LAKE EFFECT SNOW SHOWERS. WITH THE GUSTY NORTHERLY
WINDS AIDING BLOWING SNOW...EXPECT SOME AREAS TO SEE VISIBILITIES
FREQUENTLY BELOW A QUARTER MILE.
NOW FOR THE DETAILS...THE 1011MB SURFACE LOW WILL BE LOCATED OVER
EASTERN LAKE SUPERIOR AND CENTRAL UPPER MICHIGAN AT THE START OF THE
LONG TERM PERIOD AND BE QUICKLY SHIFTING EAST-SOUTHEAST THROUGH THE
DAY. MEANWHILE...A STRONG SHORTWAVE (LOCATED IN NORTHWEST ONTARIO
AND MANITOBA AT THE START OF THE PERIOD) WILL BE DIVING SOUTHEAST
ACROSS THE AREA WEDNESDAY AFTERNOON. THE COMBINATION OF THESE TWO
FEATURES WILL LEAD TO A SIGNIFICANT TRANSITION IN THE WEATHER
CONDITIONS THROUGH THE DAY ON WEDNESDAY. STILL EXPECT THERE TO BE
SOME LIGHT SNOW ONGOING OVER THE EASTERN HALF OF THE CWA AT THE
START OF THE PERIOD AND THEN SHIFTING OFF TO THE EAST. MEANWHILE
OVER THE WEST...WINDS WILL BE TURNING TO THE NORTHWEST AND EXPECT
LAKE EFFECT SNOW TO DEVELOP FAIRLY QUICKLY DURING THE MORNING HOURS.
AS THE COLD AIR SURGES INTO THE AREA...EXPECT THAT LAKE EFFECT
INTENSITY/COVERAGE TO INCREASE OVER THE WESTERN U.P. WITH 1-4
INCHES OF ACCUMULATION EXPECTED. WINDS WILL BE LIGHTER INITIALLY
WITH MUCH OF THE CLOUD WITHIN THE DGZ...SO EXPECT THE SNOW RATIOS TO
BE IN THE 20-25 TO 1 RANGE DURING THE DAY WEDNESDAY OVER THE WEST.
OVER THE EAST BEHIND THE LOW...THE NORTHWEST WINDS SHOULD LEAD TO
LAKE EFFECT DEVELOPMENT BY EARLY AFTERNOON IN THE FAVORED NORTHWEST
WIND AREAS...ALTHOUGH THE ICE OVER THE SOUTH CENTRAL LAKE WILL
LIKELY LIMIT THE INTENSITY OF THE SNOW OVER PORTIONS OF WESTERN
ALGER COUNTY.
WINDS WILL BECOME GUSTY DURING THE AFTERNOON (20-30KTS) SO HAVE
BLOWING SNOW POTENTIAL INCREASING DURING THAT TIME...BUT EXPECT THE
GUSTINESS TO REALLY KICK IN WEDNESDAY EVENING. THIS IS DUE TO A
TRAILING SURFACE TROUGH DROPPING SOUTH ACROSS THE AREA AND SHIFTING
WINDS TO THE NORTH. THUS...WILL SEE LAKE EFFECT TRANSITIONING TO
THAT FAVORED WIND DIRECTION DURING THE EVENING AND CONTINUING INTO
THURSDAY MORNING. SNOWRATIOS WILL BE LOWERING DUE TO THE INCREASING
COLD AIR AND WINDS...BUT STILL HAVE THE NORTHERLY WIND AREAS SEEING
2 TO 5 INCHES OF SNOW. WITH STEEP LOW LEVEL LAPSE RATES AND
950-925MB WINDS AT LEAST 35KTS...EXPECT GUSTS TO AROUND THAT FROM
THE KEWEENAW PENINSULA AND EASTWARD. THE STRONGEST WINDS ARE
EXPECTED TO OCCUR OVER SOUTH CENTRAL LAKE SUPERIOR AND NORTH CENTRAL
UPPER MICHIGAN...WHERE THE TIGHTEST PRESSURE GRADIENT IS EXPECTED
AND AIDED BY THE LONGER FETCH OVER ICE FREE WATERS OF
CENTRAL/EASTERN LAKE SUPERIOR. GUSTS IN THAT AREA WILL LIKELY BE
INTO THE LOW 40KTS RANGE AT TIMES WEDNESDAY NIGHT. THE COMBINATION
OF THE SNOW WITH THE BLOWING SNOW WILL FREQUENTLY REDUCE
VISIBILITIES BELOW 1/2 MILE FOR AREAS NEAR LAKE SUPERIOR. WITH THE
SEVERAL MILES OF ICE OFFSHORE FROM MARQUETTE TO MUNISING...WOULD
EXPECT THAT TO AID THE BLOWING SNOW AND WITH THE STRONGEST WINDS
EXPECTED IN THAT AREA...THINK THERE WILL BE PERIODS OF VISIBILITIES
BELOW 1/4MI (ESPECIALLY ALONG M-28). WILL CONTINUE THE HEIGHTENED
WORDING IN HWO AND WILL DEFINITELY NEED HEADLINES FOR THAT AREA
WEDNESDAY NIGHT INTO THURSDAY.
EXPECT THE SNOW INTENSITY TO DIMINISH FROM WEST TO EAST ON
THURSDAY...AS AN APPROACHING HIGH PRESSURE RIDGE FROM CENTRAL CANADA
LOWERS INVERSION HEIGHTS AND BRINGS DRIER AIR INTO THE AREA. WITH
WINDS GRADUALLY WEAKENING AND BACKING THROUGH THE DAY...SHOULD SEE
CONDITIONS IMPROVE BY THE AFTERNOON OVER THE WEST AND EVENING OVER
THE EAST. HIGHS ON THURSDAY WILL BE IN THE SINGLE DIGITS ABOVE ZERO
AND CLOSE TO THE NORMAL LOWS FOR THIS TIME OF YEAR. MODELS SEEM TO
HAVE SPEED UP THE HIGH CLOUDS FROM THE NEXT SHORTWAVE/CLIPPER TO
AFFECT THE AREA ON FRIDAY...SO THAT LEAVES LOWS ON THURSDAY NIGHT A
LITTLE UNCERTAIN UNDER THE HIGH PRESSURE MOVING THROUGH. WITH SOME
CLEARING EXPECTED IN THE EVENING OVER THE INTERIOR
WEST/CENTRAL...WILL CONTINUE TO SHOW A QUICK FALL AFTER SUNSET AND
THEN STEADY OR SLOWLY RISING TEMPERATURES OVERNIGHT.
THE AREA OF HIGH PRESSURE WILL SLIDE SOUTHEAST OF THE AREA LATE
THURSDAY NIGHT...AS ANOTHER SHORTWAVE DIVES SOUTHEAST ACROSS THE
AREA ON FRIDAY. EXPECT ANY SNOWFALL AMOUNTS TO BE LIGHT (DUSTING TO
AN INCH)...BUT IT WILL USHER IN ANOTHER PERIOD OF LAKE EFFECT SNOW
FOR LATER FRIDAY NIGHT AND SATURDAY. 850MB TEMPERATURES WILL FALL TO
AROUND -30C ON SATURDAY...WHICH WILL LIKELY HAVE HIGHS STRUGGLING TO
GET MUCH ABOVE ZERO. THAT AMOUNT OF COLD AIR WILL LEAD TO VERY FINE
FLAKE LAKE EFFECT (ALTHOUGH STRONGER BANDS WITH INVERSION HEIGHTS
TO 10-12KFT) AND WITH NORTHERLY WINDS ONCE AGAIN GUSTING TO 30-40KTS
(POSSIBLE EVEN 45KTS FOR THE MARQUETTE-MUNISING STRETCH) LATE FRIDAY
NIGHT THROUGH SATURDAY...EXPECT VERY POOR VISIBILITIES (LIKELY NEAR
ZERO AT TIMES BETWEEN MARQUETTE/MUNISING ALONG THE LAKE SUPERIOR
SHORELINE). THAT FIRST WAVE OF LAKE EFFECT AND STRONG WINDS
WEDNESDAY NIGHT AND THURSDAY WILL GIVE A GOOD FEEL TO WHAT WILL
HAPPEN FRIDAY NIGHT INTO SATURDAY. AT THIS POINT EXPECT CONDITIONS
TO BE WORSE THAN THE FIRST WAVE AND THERE WILL LIKELY BE A
PERIOD OF BLIZZARD CONDITIONS FOR THE FAVORED MARQUETTE-MUNISING
STRETCH AND PERSONS WILL LIKELY NEED TO PLAN FOR THE POSSIBILITY OF
M-28 BEING CLOSED.
A HIGH PRESSURE RIDGE WILL BUILD OVER THE AREA SATURDAY
NIGHT...LOWERING INVERSION HEIGHTS...WEAKENING WINDS...AND
GRADUALLY DIMINISHING THE LAKE EFFECT FROM WEST TO EAST. DID OPT TO
TREND POPS UP OVER THE NORTH CENTRAL FOR MUCH OF SATURDAY NIGHT DUE
TO THE LINGERING FAVORABLE FETCH OVER THE MOST ICE FREE WATERS.
ONCE THE RIDGE SHIFTS SOUTHEAST ON SUNDAY...EXPECT THE LAKE EFFECT
TO COME TO AN END AND LEAD TO A QUIETER DAY. THAT WILL LIKELY BE
SHORT LIVED AS ANOTHER (ALTHOUGH WEAKER) SHORTWAVE AND SURFACE
TROUGH MOVE THROUGH THE AREA SUNDAY NIGHT AND MONDAY. SNOWFALL
AMOUNTS LOOK TO BE LIGHT WITH THIS FEATURE AND UNDER AN INCH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1159 PM EST MON FEB 9 2015
VFR CONDITIONS WILL LIKELY PREVAIL AT KIWD THRU MID AFTN AS
LIGHT/CALM WIND BECOMES A DOWNSLOPE SE WIND. AT KCMX...MVFR CIGS
SHOULD GENERALLY BE THE RULE INTO THE AFTN WITH LIGHT WINDS OFF LAKE
SUPERIOR. AT KSAW...VFR CONDITIONS SHOULD GIVE WAY TO MVFR CIGS IN
THE NEXT FEW HRS AS LIGHT NE WINDS DEVELOP OFF LAKE SUPERIOR.
CONTINUED UPSLOPE FLOW AS WINDS VEER SE WILL HELP TO MAINTAIN MVFR
CIGS AT KSAW INTO THE AFTN. LATE IN THE AFTN AND THIS EVENING...
DISTURBANCE APPROACHING FROM THE W WILL BRING -SN/IFR CONDITIONS TO
ALL TERMINALS. NOT OUT OF THE QUESTION THAT THERE COULD BE BRIEF
LIFR THIS EVENING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 PM EST MON FEB 9 2015
A COUPLE ROUNDS AND HEAVY FREEZING SPRAY ARE EXPECTED THIS PERIOD. A
RIDGE ACROSS LAKE SUPERIOR WILL SLOWLY ERODE TUESDAY...AS A LOW
NEARS FROM THE N PLAINS. EXPECT THE LOW TO CROSS THE UPPER GREAT
LAKE TUESDAY NIGHT AND WEDNESDAY...THE LOWER GREAT LAKES WEDNESDAY
NIGHT...AND EVENTUALLY END UP DEEPENING SIGNIFICANTLY OFF THE NEW
ENGLAND COAST THURSDAY NIGHT. THIS WILL BE WHILE A HIGH ACROSS S
CENTRAL CANADA WEDNESDAY MOVES TO THE MID MS VALLEY THURSDAY NIGHT
...AND BUILDS A RIDGE ACROSS LAKE SUPERIOR LATE THURSDAY INTO
THURSDAY NIGHT. A GALE WATCH HAS BEEN ISSUED FOR MUCH OF CENTRAL TO
E LAKE SUPERIOR WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING AS
MAINLY N WINDS INCREASE W/30-40KT GUSTS.
LOOK FOR A LOW ACROSS MANITOBA THURSDAY NIGHT TO SINK ACROSS THE
UPPER GREAT LAKES FRIDAY...AND INTO THE CENTRAL APPALACHIANS
SATURDAY AFTERNOON...WHILE LARGE HIGH PRESSURE NEARS FROM THE S
CENTRAL CANADA AND THE NORTHERN PLAINS. THIS WILL BRING ABOUT
ANOTHER PERIOD OF MAINLY N GALES OF 35-40KTS OVER MUCH OF LAKE
SUPERIOR FRIDAY EVENING THROUGH SATURDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY FROM 7 PM EST /6 PM CST/ THIS EVENING TO
7 AM EST /6 AM CST/ WEDNESDAY FOR MIZ001-003>006-010-011-
013-014-084-085.
WINTER WEATHER ADVISORY FROM 2 PM EST /1 PM CST/ THIS AFTERNOON
TO 7 AM EST /6 AM CST/ WEDNESDAY FOR MIZ002-009.
LAKE SUPERIOR...
GALE WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY AFTERNOON
FOR LSZ266-267.
GALE WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING FOR
LSZ265.
GALE WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING FOR
LSZ264.
GALE WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING FOR
LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1200 AM EST TUE FEB 10 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 348 PM EST MON FEB 9 2015
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A NW FLOW ALOFT
OVER THE GREAT LKS BTWN AN UPR RDG OVER THE WRN PLAINS AND A TROF
ACROSS THE ERN CONUS. A SHRTWV EMBEDDED IN THIS NW FLOW AND
ACCOMPANYING AREA OF SOMEWHAT DEEPER MSTR/DYNAMIC FORCING THAT
LIFTED INVRN BASE UP TO ARND 4K FT AGL BROUGHT AN UPTICK THIS MRNG
TO THE LES IN THE PRESENCE OF INVRN BASE TEMPS ARND -12C OVER MAINLY
THE NCNTRL WHERE OBSVD N WINDS UPSLOPE. BUT DNVA/SUBSIDENCE IN THE
WAKE OF THE SHRTWV PASSAGE AND IN ADVANCE OF APRCHG SHRTWV RDG HAVE
CAUSED THE LES TO DIMINISH THIS AFTN...AND EVEN FOR THE LO CLDS TO
BREAK UP TO A CERTAIN EXTENT. SINCE THE 12Z INL/YPL ROABS TO THE NW
SHOW MSTR EXTENDING UP THRU ABOUT H7...PLENTY OF CLD COVER AND SOME
FLURRIES LINGER UPSTREAM IN NRN MN AND NW ONTARIO. LOOKING FARTHER
UPSTREAM...A FAIRLY VIGOROUS SHRTWV IS MOVING INTO THE PAC NW AND
OVER THE WRN RDG.
LATE TODAY/TNGT...ALTHOUGH THE LLVLS WL REMAIN COLD ENUF FOR LES...
LARGE SCALE SUBSIDENCE IN ADVANCE OF APRCHG SHRTWV RDG THAT DEPRESS
INVRN BASE TOWARD 2-3K FT WL LIMIT LES INTENSITY AND COVERAGE.
INITIALLY...LLVL LIGHT WINDS ARE FCST TO BACK TOWARD THE NW INTO
THIS EVNG AHEAD OF THE INCOMING SFC RDG. SO MOST OF THE LINGERING
LES/LK CLDS SHOULD BE TO THE E OF MQT AND OVER THE KEWEENAW THIS
EVNG. LIGHT WINDS ASSOCIATED WITH THE PASSING SFC RDG AXIS MAY ALLOW
FOR A MESOLO PRES TO DVLP. HOWEVER...PRESENCE OF A GOOD DEAL OF ICE
NEAR LK SUP E OF MARQUETTE WL LIMIT THE POTENTIAL IMPACT OF THIS
FEATURE IN THESE AREAS. AS THE WINDS TEND TO SHIFT BACK TO THE NE
LATER FOLLOWING THE PASSAGE OF THE RDG AXIS TO THE E...SOME LES
MIGHT SHIFT BACK TOWARD MARQUETTE. ANOTHER WEAK SHRTWV/AREA OF DEEP
LYR QVECTOR CNVGC IS FCST TO MOVE BY LATE TNGT. BUT SINCE SFC RDG
AXIS WL BE PASSING THRU AT THAT TIME...THE IMPACT SHOULD BE MINIMAL.
EXPECT THE LOWEST MIN TEMPS OVER THE E AND SCNTRL WHERE LIGHT E
WINDS WL DRAIN OFF SOME VERY COLD OVER ONTARIO AND MSTR/CLDS TO THE
NW WL HAVE A HARDER TIME REACHING.
TUE...LARGE SCALE WAA/DEEP LYR QVECTOR CNVGC/UPR DVGC IN INCRSG SSE
FLOW BTWN DEPARTING SFC HI PRES RDG TO THE E AND IN ADVANCE OF
SHRTWV NOW OVER THE PAC NW THAT WL BE MOVING THRU THE NRN PLAINS IS
FCST TO ARRIVE IN THE AFTN. THE ARRIVAL OF THIS FORCING AND
ACCOMPANYING UVV WL ALLOW FOR THICKENING CLDS AND SOME SN TO PUSH
INTO THE WRN COUNTIES DURING THE AFTN. H7 SPECIFIC HUMIDITY FCST UP
TO 3 G/KG UNDER THE AXIS OF WAA INDICATES A FEW INCHES OF SN MAY
ACCUMULATE OVER THE FAR W BY 00Z DESPITE A RATHER HI...NARROW DGZ.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 510 PM EST MON FEB 9 2015
BOUTS OF COLD AND SNOW WILL BE THE THEME FOR THE LONG TERM PERIOD.
SNOW WILL BE EXPANDING W TO E ACROSS THE CWA TUESDAY NIGHT AS THE
MAIN SFC LOW OVER S AND CENTRAL MN CROSSES FAR W BY 06Z...AND SPLITS
THE AREA IN HALF BY 12Z WEDNESDAY. 850MB TEMPS WILL FALL TO AROUND -
12C BEHIND THE LOW...WITH -20C AIR WEDNESDAY EVENING ON FAVORABLE
UPSLOPE FLOW.
CONTINUED TO MENTION THE POTENTIAL FOR WIDESPREAD SNOW TUESDAY
AFTERNOON THROUGH TUESDAY NIGHT WITH A FEW INCHES OF SNOW
ACCUMULATION POSSIBLE...THEN LAKE EFFECT SNOW WEDNESDAY INTO
THURSDAY. GUSTY NW TO N WINDS WILL HELP PRODUCE BLOWING SNOW AND
REDUCED VIS WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING. MAY NEED
TO ISSUE WINTER WX ADVISORY FOR THE 2-4.5IN OF SNOW TUESDAY THROUGH
DAYBREAK WEDNESDAY...AND DEPENDING ON THE FOCUS OF MODERATE LES FOR
SNOW AND BLOWING SNOW FOR THE LONGER DURATION LES FOR THE N WIND
FAVORED AREAS OF GOGEBIC/ONTONAGON AND BARAGA/MARQUETTE E ALONG LAKE
SUPERIOR AS 850MB TEMPS FALL TO AROUND -25C.
WITH ALL THIS COLD AIR...WIND CHILL VALUES ARE EXPECTED TO FALL
BETWEEN 15 BELOW AND 25 BELOW ZERO THURSDAY MORNING INLAND FROM THE
GREAT LAKES.
THE N WINDS WILL ALSO BE A CONCERN FOR LATE FRIDAY EVENING THROUGH
ALL OF SATURDAY...WITH THE BEST CHANCE OF LES N CENTRAL. DID BUMP UP
THE WINDS/GUSTS APPROX 5KTS SATURDAY MORNING. LOOKING AT IT FROM A
DIFFERENT PERSPECTIVE...THIS WIND SATURDAY WILL PROBABLY RESULT IN A
RESTRICTION OR ROAD CLOSURE OF M-28 EAST OF HARVEY THROUGH MUNISING
LATE FRIDAY NIGHT THROUGH SATURDAY MORNING...ESPECIALLY CONSIDERING
THE AMOUNT OF SNOW THAT WILL BE ABLE TO ACCUMULATE ON THE SNOW JUST
OFFSHORE. AS THIS IS STILL 4-5 DAYS OUT...LOOK FOR ADJUSTMENTS TO
THE ONGOING FCST. IMPROVING CONDITIONS WILL COME IN SATURDAY NIGHT
AS THE SFC LOW SINING ACROSS THE UPPER GREAT LAKES FRIDAY
AFTERNOON/EVENING PUSHES TO THE CENTRAL APPALACHIANS BY SATURDAY
AFTERNOON. VERY STRONG HIGH PRESSURE ACROSS S CANADA AND THE CENTRAL
PLAINS WILL THEN SLOWLY MOVE IN. THE SFC RIDGE WILL BE
DIRECTLY OVERHEAD SUNDAY MORNING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1159 PM EST MON FEB 9 2015
VFR CONDITIONS WILL LIKELY PREVAIL AT KIWD THRU MID AFTN AS
LIGHT/CALM WIND BECOMES A DOWNSLOPE SE WIND. AT KCMX...MVFR CIGS
SHOULD GENERALLY BE THE RULE INTO THE AFTN WITH LIGHT WINDS OFF LAKE
SUPERIOR. AT KSAW...VFR CONDITIONS SHOULD GIVE WAY TO MVFR CIGS IN
THE NEXT FEW HRS AS LIGHT NE WINDS DEVELOP OFF LAKE SUPERIOR.
CONTINUED UPSLOPE FLOW AS WINDS VEER SE WILL HELP TO MAINTAIN MVFR
CIGS AT KSAW INTO THE AFTN. LATE IN THE AFTN AND THIS EVENING...
DISTURBANCE APPROACHING FROM THE W WILL BRING -SN/IFR CONDITIONS TO
ALL TERMINALS. NOT OUT OF THE QUESTION THAT THERE COULD BE BRIEF
LIFR THIS EVENING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 PM EST MON FEB 9 2015
A COUPLE ROUNDS AND HEAVY FREEZING SPRAY ARE EXPECTED THIS PERIOD. A
RIDGE ACROSS LAKE SUPERIOR WILL SLOWLY ERODE TUESDAY...AS A LOW
NEARS FROM THE N PLAINS. EXPECT THE LOW TO CROSS THE UPPER GREAT
LAKE TUESDAY NIGHT AND WEDNESDAY...THE LOWER GREAT LAKES WEDNESDAY
NIGHT...AND EVENTUALLY END UP DEEPENING SIGNIFICANTLY OFF THE NEW
ENGLAND COAST THURSDAY NIGHT. THIS WILL BE WHILE A HIGH ACROSS S
CENTRAL CANADA WEDNESDAY MOVES TO THE MID MS VALLEY THURSDAY NIGHT
...AND BUILDS A RIDGE ACROSS LAKE SUPERIOR LATE THURSDAY INTO
THURSDAY NIGHT. A GALE WATCH HAS BEEN ISSUED FOR MUCH OF CENTRAL TO
E LAKE SUPERIOR WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING AS
MAINLY N WINDS INCREASE W/30-40KT GUSTS.
LOOK FOR A LOW ACROSS MANITOBA THURSDAY NIGHT TO SINK ACROSS THE
UPPER GREAT LAKES FRIDAY...AND INTO THE CENTRAL APPALACHIANS
SATURDAY AFTERNOON...WHILE LARGE HIGH PRESSURE NEARS FROM THE S
CENTRAL CANADA AND THE NORTHERN PLAINS. THIS WILL BRING ABOUT
ANOTHER PERIOD OF MAINLY N GALES OF 35-40KTS OVER MUCH OF LAKE
SUPERIOR FRIDAY EVENING THROUGH SATURDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY AFTERNOON
FOR LSZ266-267.
GALE WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING FOR
LSZ265.
GALE WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING FOR
LSZ264.
GALE WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING FOR
LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...ROLFSON
MARINE...KF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
401 AM CST TUE FEB 10 2015
.UPDATE...
ISSUED AT 959 PM CST MON FEB 9 2015
AFTER WATCHING SEVERAL RUNS OF THE RAP...HRRR...AND HOPWRF DECIDED
TO EXPAND THE ADVISORY SLIGHTLY SOUTH AND EAST TO ENCOMPASS THE
ENTIRE TWIN CITIES METRO AND THE REST OF WEST CENTRAL WISCONSIN.
NOT MUCH ON RADAR OUT TO THE WEST LATE THIS EVENING...BUT
STRENGTHENING WAA OVERNIGHT WILL ALLOW PRECIP TO BLOSSOM ACROSS
THE EASTERN DAKOTAS AFTER 06-08Z. THIS WAA WILL MAXIMIZE AROUND
12Z ACROSS WRN MN...15Z ACROSS ERN MN...AND 18Z OVER WRN WI. A
DEEP MOIST LAYER AND HIGH DGZ CENTERED AROUND 550 MB ALLOWS FOR
NOT ONLY A HIGH MOISTURE CONTENT ATMOSPHERE WITH PW VALUES ABOVE
0.6 INCHES /NEARING 3 STANDARD DEVIATIONS ABOVE AVERAGE/...BUT
ALSO SOME CAPE FROM THE DGZ UPWARD AND THUS CONVECTIVE POTENTIAL.
THE STRONG FORCING WITH THIS BAND COUPLED WITH THE MOISTURE
CONTENT AND WEAK INSTABILITY ALOFT SHOULD ALLOW THE INITIAL BAND
OF PRECIP TO BECOME PRETTY INTENSE FOR A TIME. RAPIDLY DETERIORATING
CONDITIONS ARE THUS EXPECTED SHORTLY AFTER THE ONSET. FOR SEVERAL
RUNS...THE RAP HAS HINTED AT 1-2 INCH PER HOUR RATES AS THE BAND
PUSHES INTO ERN MN AND WRN WI AND THIS SEEMS REASONABLE.
IF THIS WERE TO PERSIST FOR MORE THAN A COUPLE HOURS...COULD
PROBABLY JUSTIFY A WARNING. HOWEVER...THERE ARE SOME
SIGNS...PARTICULARLY ACROSS WRN AND SRN MN...THAT ONCE THIS BAND
GOES THROUGH THAT MAY BE IT FOR STEADY PRECIP AS DRY SLOTTING
COMES IN.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 413 PM CST MON FEB 9 2015
TURNED OUT TO BE A BEAUTIFUL DAY OUTSIDE OF WESTERN AND FAR SOUTHERN
MN...AS A WEDGE OF DRY AIR EMANATING FROM HIGH PRESSURE MOVING INTO
WRN ONTARIO HELPED CLEAR SKIES OUT. HOWEVER...TROUBLE IS ALREADY
BREWING TO OUR WEST AS WATER VAPOR IMAGERY SHOWS A POWERFUL WAVE
MOVING ACROSS THE NW CONUS. THIS WAVE WILL QUICKLY WORK ACROSS THE
DAKOTAS TONIGHT AND MN TUESDAY...PROVIDING US WITH THE POTPOURRI OF
WINTRY PRECIPITATION ON TUESDAY THAT WE HAVE BEEN ADVERTISING FOR
THE LAST SEVERAL DAYS.
WE DID NOT SEE MUCH CHANGE IN THE GUIDANCE TODAY WITH WHAT WAS SEEN
LAST NIGHT...SO THIS FORECAST DID NOT CHANGE A WHOLE LOT
EITHER...WITH ABOUT THE ONLY CHANGE OF SIGNIFICANCE BEING TO SLOW
DOWN HOW QUICKLY PRECIP MOVES INTO AND THEN ACROSS THE MPX CWA.
THIS FORECAST FAVORED THE GFS FOR BOTH P-TYPE AND QPF. FOR P-
TYPE...THE NAM...ALONG WITH THE RAP WERE CONSIDERABLY WARMER WITH
THE WARM NOSE ALOFT THAN THE GFS/ECMWF. HAD WE GONE THE NAM
ROUTE...A MIX WOULD HAVE BEEN MENTIONED FARTHER NORTH THAN IT IS
TUESDAY AFTERNOON...AND SAID MIX WOULD BE MORE OF A FZRA/SLEET/SNOW
MIX /MOST LIKELY TO LEAST LIKELY/ AS OPPOSED TO THE CURRENT
SLEET/SNOW/FZRA MIX THAT WE HAVE.
FOR QPF...THE NAM IS A CONSIDERABLE SRN OUTLIER. THE POTENTIAL
PROBLEM WITH IT STARTS TONIGHT...WHEN THE NAM SHOWS NEARLY A QUARTER
INCH OF QPF FALLING BY 12Z TUESDAY IN NE SODAK...IN ADDITION TO
ANOTHER QPF BULLSEYE FROM CENTRAL NODAK INTO SE NODAK. THE RAP AND
HOPWRF HAVE THE NODAK BULLSEYE...BUT SHOW CONSIDERABLY LESS QPF INTO
SODAK. THE LATENT HEAT DIFFERENCES THIS CREATES THEN CASCADES INTO
TUESDAY...WHEN THE NAM SHOWS QPF IN EXCESS OF 0.3" ALL THE WAY DOWN
TO MANKATO. THE GFS ON THE OTHER HAND HAS THE NODAK QPF...BUT MUCH
LOWER QPF DOWN INTO SODAK...SIMILAR TO WHAT THE RAP/HOPWRF
HAVE...HENCE FAVORING THE QPF THAT DIRECTION. WE THEN TEMPERED THE
GFS QPF A BIT WITH THE ECMWF/SREF AND ENDED UP WITH 0.3" QPF DOWN
ABOUT AS FAR SOUTH AS THE TWIN CITIES DOWN TO MENOMONIE.
CONVERTING THIS QPF OVER TO SNOW WITH RATIOS IN THE 10-12:1 RANGE
AND WE ENDED UP WITH SNOWFALL AMOUNTS BETWEEN 2 AND 5 INCHES NORTH
OF A MORRIS/MINNEAPOLIS/EAU CLAIRE LINE WITH THE LARGEST AMOUNTS
UP AROUND MILLE LACS LAKE TO POINTS EAST.
THE HEAVIEST SNOW IS EXPECTED IN CENTRAL MN AS THEY WILL GET THE
COMBINATION OF WAA AND DEFORMATION SNOW. FARTHER SOUTH...THE
MAJORITY OF THE PRECIP WILL FALL IN THE WAA BAND. THIS WILL RESULT
IN A 2-4 HOUR WINDOW WHERE SNOWFALL RATES ARE LIKELY NEAR OR IN
EXCESS OF AN INCH PER HOUR...SO THIS SNOW WILL FALL IN A SHORT
AMOUNT OF TIME. TIMING WISE...THINGS DO NOT LOOK TO BE TO DISSIMILAR
FROM WHAT WE SAW LAST TUESDAY WHEN ABOUT 2 INCHES OF SNOW SEVERAL
IMPACTED THE EVENING COMMUTE IN THE TWIN CITIES. WITH A SIMILAR
SCENARIO EXPECTED TO TO PLAY OUT TOMORROW...PULLED THE ADVISORY DOWN
TO COVER ALL BUT THE SRN TWIN CITIES METRO. DECIDED AGAINST PUTTING
HEADLINES ANY FARTHER SOUTH THAN WHAT WE HAVE NOW SINCE THERE ARE
MORE QUESTIONS AS TO HOW MUCH PRECIP LOCATIONS FARTHER SOUTH WILL
ACTUALLY SEE. IN ADDITION...WITH CURRENT PRIMARY P-TYPE EXPECTED TO
BE SLEET AS OPPOSED TO FREEZING RAIN...THAT WILL LIMIT THE TRAVEL
IMPACT FROM THIS PRECIP AS WELL. HOWEVER...THIS WILL BE AN AREA THAT
WILL NEED TO BE CLOSELY MONITORED THROUGH THE NIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 400 AM CST TUE FEB 10 2015
IN THE LONG TERM PERIOD...MAIN ITEMS OF NOTE ARE THE BELOW NORMAL
TEMPERATURES EXPECTED WITH A COUPLE COLD FRONTS MOVING THROUGH
DURING THE PERIOD AND OVERALL NORTHWEST FLOW...AND THE LIMITED
PRECIPITATION AMOUNTS EXPECTED.
WEDNESDAY THROUGH THURSDAY...THE SYSTEM THAT WILL BRING SNOW AND A
WINTRY MIX THROUGH THE AREA TODAY WILL BE DEPARTING BY WEDNESDAY
MORNING. CYCLONIC FLOW WILL CONTINUE IN TO THURSDAY BEFORE BECOMING
ANTI-CYCLONIC IN CONJUNCTION WITH AN INCOMING SURFACE HIGH FOR
THURSDAY. MODEL SOUNDINGS INDICATE LOW LEVEL SATURATION AND WEAK
LIFT LINGERING IN EASTERN MN AND ESPECIALLY WESTERN WI...SO KEPT LOW
POPS IN THE FORECAST FOR LIGHT SNOW/FLURRIES THERE FOR WEDNESDAY
MORNING. FOR THE AFTERNOON AND NIGHT...LOW LEVEL LAPSE RATES STEEPEN
IN THE EAST SO THE POTENTIAL FOR SNOW SHOWER DEVELOPMENT IS DECENT.
WESTERN WI COULD SEE A QUICK DUSTING TO A FEW TENTHS OF AN INCH FROM
THESE SNOW SHOWERS. AS FAR AS TEMPERATURES ARE
CONCERNED...TEMPERATURES WILL ONLY FALL THROUGH THE DAY ON WEDNESDAY
THANKS TO STRONG COLD AIR ADVECTION. THE SURFACE PRESSURE GRADIENT
LOOKS FAIRLY TIGHT ACROSS THE STATE...WITH ABOUT A 10MB DIFFERENCE
ACROSS THE STATE THROUGH THE DAY...SO IT WILL BE VERY
WINDY...ESPECIALLY ACROSS WESTERN MN. NOT A PLEASANT DAY AT ALL FOR
OUTDOOR ACTIVITIES WITH WIND CHILLS NEAR OR BELOW ZERO DURING THE
DAYLIGHT HOURS. WITH THE ARCTIC SURGE CONTINUING...EXPECTING LOW
TEMPERATURES TO FALL BELOW ZERO ACROSS ESSENTIALLY ALL OF THE
FORECAST AREA. WINDS WILL EASILY STAY UP IN THE 10-20MPH RANGE
OVERNIGHT SO WIND CHILL VALUES BY EARLY THURSDAY MORNING WILL RANGE
FROM -20F T0 -30F. CLOUDS SHOULD CLEAR THURSDAY AS THE SURFACE HIGH
PUSHES IN BY MID DAY...AND WINDS WILL WEAKEN THROUGH THE DAY
THURSDAY AS THE GRADIENT WEAKENS. WITH THE ARCTIC AIR MASS IN
PLACE...EXPECTING HIGH TEMPERATURES 15-20 DEGREES BELOW AVERAGE ON
THURSDAY.
THURSDAY NIGHT THROUGH SATURDAY NIGHT...A CLIPPER SYSTEM WILL COME
RACING SOUTHEAST THROUGH CANADA AND WE`LL BE SOUTH OF THE HIGHEST
PRECIP AMOUNTS...BUT STILL LOOKS LIKE A DECENT SHOT OF VERY LIGHT
SNOW/FLURRIES WITH THIS WAVE. AS IT MOVES EAST OF US BY
FRIDAY...ANOTHER ARCTIC SURGE WILL ADVANCE INTO THE UPPER MIDWEST
THROUGH SATURDAY. THE CORE OF THE COLD AIR THIS TIME LOOKS TO DIVE
THROUGH WESTERN WI/EASTERN MN. ANOTHER BELOW ZERO NIGHT LIKELY
FRIDAY NIGHT...WITH HIGH TEMPERATURES SATURDAY NOT ESCAPING THE
SINGLE DIGITS IN STRONG NORTHWEST FLOW...SO AGAIN NOT A PLEASANT DAY
FOR OUTDOOR ACTIVITIES.
SUNDAY THROUGH TUESDAY...REALLY A VERY SIMILAR STORY FOR THIS
PERIOD. ANOTHER NORTHERN WAVE WILL MOVE SOUTHEAST ACROSS CANADA AND
PROVIDE US WITH THE POTENTIAL TO SEE LIGHT SNOW ON SUNDAY AND SUNDAY
NIGHT...WHICH WILL BE FOLLOWED BY YET ANOTHER ARCTIC SURGE INTO
EARLY NEXT WEEK. AT THIS POINT...TUESDAY WILL BE VERY SIMILAR TO
SATURDAY IN TERMS OF COLD TEMPS AND STRONG NORTHWEST WINDS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1218 AM CST TUE FEB 10 2015
VFR CONDITIONS EVERYWHERE EXCEPT SOUTHWEST AND FAR WRN MN AT TAF
ISSUANCE TIME...BUT PRECIPITATION IS NOW DEVELOPING ACROSS SOUTH
DAKOTA WHICH WILL PUSH EAST INTO WRN MN LATE TONIGHT...ERN MN BY
MID MORNING...AND WRN WI LATE MORNING. THIS IS EXPECTED TO BRING A
PERIOD OF MODERATE TO HEAVY PRECIP ACROSS MOST OF THE AREA FOR A
3-4 HOUR WINDOW BEFORE LIGHTER SNOW FOLLOWS FOR SEVERAL MORE
HOURS. SEVERAL MODELS ARE INDICATING POTENTIAL FOR 1-2 INCH PER
HOUR RATES WITH THE HEAVY ROUND AND A FEW THUNDERSTORMS MAY ALSO
ACCOMPANY IT...PARTICULARLY ACROSS SRN MN. ALSO OF NOTE...A THIN
BAND OF SN/PL APPEARS TO BE IN THE EARLY STAGES OF DEVELOPING
AHEAD OF THE MAIN AREA OF PRECIP...FROM MADISON TO MARHSALL. THIS
WILL PUSH ACROSS OVERNIGHT AND SHOULD NOT AMOUNT TO MUCH OTHER
THAN A BRIEF PERIOD OF PRECIP. DID ACCOUNT FOR THIS AS A TEMPO
BEFORE THE MAIN ROUND...BUT CONFIDENCE IS LOW.
KMSP...SIGNIFICANT IMPACTS POSSIBLE FROM MID MORNING TO EARLY
AFTERNOON AS A ROUND OF HEAVY SNOW IS LOOKING MORE LIKELY TO
IMPACT THE AREA. MANY MODELS HAVE SHOWN THIS WITH GOOD CONSISTENCY
FOR THE LAST SEVERAL HOURS...SO FELT CONFIDENT ENOUGH TO INCLUDE
IN THIS TAF ISSUANCE. SNOW RATES OF 1-2 INCHES PER HOUR ARE LIKELY
IF THIS DOES UNFOLD WITH LIFR CONDITIONS PERSISTING 3-4 HOURS.
/OUTLOOK FOR KMSP/
WED...MVFR WITH FLURRIES POSSIBLE. WINDS NW 15G30KT.
THU...BCMG VFR. WINDS BCMG LGT/VAR.
FRI...CHC MVFR CIGS. WINDS SW 5-10 KTS BCMG NW 15-20G25 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR
MNZ043>045-050>053-059>063-068>070-076-077-084-085-093.
WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR MNZ041-
042-047>049-054>058-064>067-073>075-082-083-091-092.
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR MNZ078.
WI...WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR WIZ014>016-023>028.
&&
$$
UPDATE...BORGHOFF
SHORT TERM...MPG
LONG TERM...SPD
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
1218 AM CST TUE FEB 10 2015
.UPDATE...
ISSUED AT 959 PM CST MON FEB 9 2015
AFTER WATCHING SEVERAL RUNS OF THE RAP...HRRR...AND HOPWRF DECIDED
TO EXPAND THE ADVISORY SLIGHTLY SOUTH AND EAST TO ENCOMPASS THE
ENTIRE TWIN CITIES METRO AND THE REST OF WEST CENTRAL WISCONSIN.
NOT MUCH ON RADAR OUT TO THE WEST LATE THIS EVENING...BUT
STRENGTHENING WAA OVERNIGHT WILL ALLOW PRECIP TO BLOSSOM ACROSS
THE EASTERN DAKOTAS AFTER 06-08Z. THIS WAA WILL MAXIMIZE AROUND
12Z ACROSS WRN MN...15Z ACROSS ERN MN...AND 18Z OVER WRN WI. A
DEEP MOIST LAYER AND HIGH DGZ CENTERED AROUND 550 MB ALLOWS FOR
NOT ONLY A HIGH MOISTURE CONTENT ATMOSPHERE WITH PW VALUES ABOVE
0.6 INCHES /NEARING 3 STANDARD DEVIATIONS ABOVE AVERAGE/...BUT
ALSO SOME CAPE FROM THE DGZ UPWARD AND THUS CONVECTIVE POTENTIAL.
THE STRONG FORCING WITH THIS BAND COUPLED WITH THE MOISTURE
CONTENT AND WEAK INSTABILITY ALOFT SHOULD ALLOW THE INITIAL BAND
OF PRECIP TO BECOME PRETTY INTENSE FOR A TIME. RAPIDLY DETERIORATING
CONDITIONS ARE THUS EXPECTED SHORTLY AFTER THE ONSET. FOR SEVERAL
RUNS...THE RAP HAS HINTED AT 1-2 INCH PER HOUR RATES AS THE BAND
PUSHES INTO ERN MN AND WRN WI AND THIS SEEMS REASONABLE.
IF THIS WERE TO PERSIST FOR MORE THAN A COUPLE HOURS...COULD
PROBABLY JUSTIFY A WARNING. HOWEVER...THERE ARE SOME
SIGNS...PARTICULARLY ACROSS WRN AND SRN MN...THAT ONCE THIS BAND
GOES THROUGH THAT MAY BE IT FOR STEADY PRECIP AS DRY SLOTTING
COMES IN.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 413 PM CST MON FEB 9 2015
TURNED OUT TO BE A BEAUTIFUL DAY OUTSIDE OF WESTERN AND FAR SOUTHERN
MN...AS A WEDGE OF DRY AIR EMANATING FROM HIGH PRESSURE MOVING INTO
WRN ONTARIO HELPED CLEAR SKIES OUT. HOWEVER...TROUBLE IS ALREADY
BREWING TO OUR WEST AS WATER VAPOR IMAGERY SHOWS A POWERFUL WAVE
MOVING ACROSS THE NW CONUS. THIS WAVE WILL QUICKLY WORK ACROSS THE
DAKOTAS TONIGHT AND MN TUESDAY...PROVIDING US WITH THE POTPOURRI OF
WINTRY PRECIPITATION ON TUESDAY THAT WE HAVE BEEN ADVERTISING FOR
THE LAST SEVERAL DAYS.
WE DID NOT SEE MUCH CHANGE IN THE GUIDANCE TODAY WITH WHAT WAS SEEN
LAST NIGHT...SO THIS FORECAST DID NOT CHANGE A WHOLE LOT
EITHER...WITH ABOUT THE ONLY CHANGE OF SIGNIFICANCE BEING TO SLOW
DOWN HOW QUICKLY PRECIP MOVES INTO AND THEN ACROSS THE MPX CWA.
THIS FORECAST FAVORED THE GFS FOR BOTH P-TYPE AND QPF. FOR P-
TYPE...THE NAM...ALONG WITH THE RAP WERE CONSIDERABLY WARMER WITH
THE WARM NOSE ALOFT THAN THE GFS/ECMWF. HAD WE GONE THE NAM
ROUTE...A MIX WOULD HAVE BEEN MENTIONED FARTHER NORTH THAN IT IS
TUESDAY AFTERNOON...AND SAID MIX WOULD BE MORE OF A FZRA/SLEET/SNOW
MIX /MOST LIKELY TO LEAST LIKELY/ AS OPPOSED TO THE CURRENT
SLEET/SNOW/FZRA MIX THAT WE HAVE.
FOR QPF...THE NAM IS A CONSIDERABLE SRN OUTLIER. THE POTENTIAL
PROBLEM WITH IT STARTS TONIGHT...WHEN THE NAM SHOWS NEARLY A QUARTER
INCH OF QPF FALLING BY 12Z TUESDAY IN NE SODAK...IN ADDITION TO
ANOTHER QPF BULLSEYE FROM CENTRAL NODAK INTO SE NODAK. THE RAP AND
HOPWRF HAVE THE NODAK BULLSEYE...BUT SHOW CONSIDERABLY LESS QPF INTO
SODAK. THE LATENT HEAT DIFFERENCES THIS CREATES THEN CASCADES INTO
TUESDAY...WHEN THE NAM SHOWS QPF IN EXCESS OF 0.3" ALL THE WAY DOWN
TO MANKATO. THE GFS ON THE OTHER HAND HAS THE NODAK QPF...BUT MUCH
LOWER QPF DOWN INTO SODAK...SIMILAR TO WHAT THE RAP/HOPWRF
HAVE...HENCE FAVORING THE QPF THAT DIRECTION. WE THEN TEMPERED THE
GFS QPF A BIT WITH THE ECMWF/SREF AND ENDED UP WITH 0.3" QPF DOWN
ABOUT AS FAR SOUTH AS THE TWIN CITIES DOWN TO MENOMONIE.
CONVERTING THIS QPF OVER TO SNOW WITH RATIOS IN THE 10-12:1 RANGE
AND WE ENDED UP WITH SNOWFALL AMOUNTS BETWEEN 2 AND 5 INCHES NORTH
OF A MORRIS/MINNEAPOLIS/EAU CLAIRE LINE WITH THE LARGEST AMOUNTS
UP AROUND MILLE LACS LAKE TO POINTS EAST.
THE HEAVIEST SNOW IS EXPECTED IN CENTRAL MN AS THEY WILL GET THE
COMBINATION OF WAA AND DEFORMATION SNOW. FARTHER SOUTH...THE
MAJORITY OF THE PRECIP WILL FALL IN THE WAA BAND. THIS WILL RESULT
IN A 2-4 HOUR WINDOW WHERE SNOWFALL RATES ARE LIKELY NEAR OR IN
EXCESS OF AN INCH PER HOUR...SO THIS SNOW WILL FALL IN A SHORT
AMOUNT OF TIME. TIMING WISE...THINGS DO NOT LOOK TO BE TO DISSIMILAR
FROM WHAT WE SAW LAST TUESDAY WHEN ABOUT 2 INCHES OF SNOW SEVERAL
IMPACTED THE EVENING COMMUTE IN THE TWIN CITIES. WITH A SIMILAR
SCENARIO EXPECTED TO TO PLAY OUT TOMORROW...PULLED THE ADVISORY DOWN
TO COVER ALL BUT THE SRN TWIN CITIES METRO. DECIDED AGAINST PUTTING
HEADLINES ANY FARTHER SOUTH THAN WHAT WE HAVE NOW SINCE THERE ARE
MORE QUESTIONS AS TO HOW MUCH PRECIP LOCATIONS FARTHER SOUTH WILL
ACTUALLY SEE. IN ADDITION...WITH CURRENT PRIMARY P-TYPE EXPECTED TO
BE SLEET AS OPPOSED TO FREEZING RAIN...THAT WILL LIMIT THE TRAVEL
IMPACT FROM THIS PRECIP AS WELL. HOWEVER...THIS WILL BE AN AREA THAT
WILL NEED TO BE CLOSELY MONITORED THROUGH THE NIGHT.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 413 PM CST MON FEB 9 2015
THE EXTENDED PERIOD CAN BE CHARACTERIZED AS BLW NORMAL IN TERMS OF
TEMPERATURES AS THE MEAN PATTERN SHIFTS TO A MORE NW
DIRECTION...LEADING TO COLDER CANADIAN AIR FILTERING SOUTHWARD.
A BRIEF PERIOD TUESDAY EVENING OF MIXED PRECIPITATION ALONG THE MN
RIVER VALLEY WILL QUICKLY CHG TO ALL SNOW AS A MUCH COLDER AIR MASS
REPLACES THE CURRENT ONE. BASED ON THE STRENGTH OF A SECONDARY
SHRTWV MOVING SE ACROSS THE UPPER MIDWEST TUESDAY NIGHT/WEDNESDAY
AND THE STRENGTH OF THE CAA BEHIND IT...BREEZY/WINDY CONDS WILL
DEVELOP...ESPECIALLY IN THE TYPICAL AREAS OF WC/SC MN WHERE GUSTS UP
TO 45 MPH WILL BE COMMON. WAS CONSIDERING A BLOWING SNOW PROBLEM IN
THESE AREAS...BUT DO TO A LACK OF SNOW COVER AND NO ADDITIONAL NEW
SNOW EXPECTED...DO NOT ANTICIPATE ANY CONCERNS.
VERY LITTLE CHC/S OF PRECIPITATION IS EXPECTED PAST TUESDAY
EVENING...WITH THE EXCEPTION BY NEXT MONDAY AS THE MEAN PATTERN WILL
REMAIN DRY AND UNEVENTFUL. TWO STRONG COLD FRONTS WILL MOVE ACROSS
OUR REGION...ONE WILL OCCUR TUESDAY AFTN/EVENING...AND ANOTHER
FRIDAY AFTN/SATURDAY MORNING. THESE FRONTS WILL CAUSE A FEW SNOW
SHOWERS TO DEVELOP...BUT AGAIN NOT EXPECTING MUCH IN THE WAY OF
ACCUMULATIONS.
OVER THE PAST TWO MONTHS...THE MEAN AREA OF ARCTIC AIR HAS REMAINED
ACROSS NE NORTH AMERICA...AFFECTING MAINLY THE NE CONUS...AND
EASTERN CANADA. ONCE IN A WHILE A BRIEF COLD SPELL MOVES ACROSS THE
UPPER MIDWEST/GREAT LAKES AS THE PATTERN BUCKLES. THE LATEST
PROBABILISTIC FORECASTS ON NCEP GEFS REFORECASTS CFS/V2...HAS 50H
ANOMALIES SHIFTING ACROSS THE ALASKA REGION...WITH A SECONDARY 50H
ANOMALY FOCUSING ACROSS THE DEEP SOUTH/SW. THIS BASICALLY SHIFTS THE
COLDER AIR ACROSS NORTHEAST CANADA FURTHER TO THE SW ACROSS THE
GREAT LAKES...AND THE EASTERN 1/3 OF NORTH AMERICA. THIS ALSO
SUGGESTS A STRONGER CORRELATION OF ABV NORMAL ANOMALIES FOCUSING
ACROSS THE GREAT BASIN AND THE FAR WEST COAST. THE TIME FRAME FOR
THIS PERIOD IS FEB 15 TO FEB 24. THE 45 DAY CFS PLUMES FOR THE PAST
4 RUNS DOES SUPPORT THE COLDER PATTERN DEVELOPING IN OUR REGION FOR
THE SECOND AND THIRD WEEK OF FEB 24. IN ADDITION...IT SEEMS IT MAYBE
A WETTER PATTERN AS THE STRONGER JET WORKS ACROSS THE CENTRAL
CONUS...LEADING TO A BETTER CHC OF A THERMAL BOUNDARY AND WIDESPREAD
PRECIPITATION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1218 AM CST TUE FEB 10 2015
VFR CONDITIONS EVERYWHERE EXCEPT SOUTHWEST AND FAR WRN MN AT TAF
ISSUANCE TIME...BUT PRECIPITATION IS NOW DEVELOPING ACROSS SOUTH
DAKOTA WHICH WILL PUSH EAST INTO WRN MN LATE TONIGHT...ERN MN BY
MID MORNING...AND WRN WI LATE MORNING. THIS IS EXPECTED TO BRING A
PERIOD OF MODERATE TO HEAVY PRECIP ACROSS MOST OF THE AREA FOR A
3-4 HOUR WINDOW BEFORE LIGHTER SNOW FOLLOWS FOR SEVERAL MORE
HOURS. SEVERAL MODELS ARE INDICATING POTENTIAL FOR 1-2 INCH PER
HOUR RATES WITH THE HEAVY ROUND AND A FEW THUNDERSTORMS MAY ALSO
ACCOMPANY IT...PARTICULARLY ACROSS SRN MN. ALSO OF NOTE...A THIN
BAND OF SN/PL APPEARS TO BE IN THE EARLY STAGES OF DEVELOPING
AHEAD OF THE MAIN AREA OF PRECIP...FROM MADISON TO MARHSALL. THIS
WILL PUSH ACROSS OVERNIGHT AND SHOULD NOT AMOUNT TO MUCH OTHER
THAN A BRIEF PERIOD OF PRECIP. DID ACCOUNT FOR THIS AS A TEMPO
BEFORE THE MAIN ROUND...BUT CONFIDENCE IS LOW.
KMSP...SIGNIFICANT IMPACTS POSSIBLE FROM MID MORNING TO EARLY
AFTERNOON AS A ROUND OF HEAVY SNOW IS LOOKING MORE LIKELY TO
IMPACT THE AREA. MANY MODELS HAVE SHOWN THIS WITH GOOD CONSISTENCY
FOR THE LAST SEVERAL HOURS...SO FELT CONFIDENT ENOUGH TO INCLUDE
IN THIS TAF ISSUANCE. SNOW RATES OF 1-2 INCHES PER HOUR ARE LIKELY
IF THIS DOES UNFOLD WITH LIFR CONDITIONS PERSISTING 3-4 HOURS.
/OUTLOOK FOR KMSP/
WED...MVFR WITH FLURRIES POSSIBLE. WINDS NW 15G30KT.
THU...BCMG VFR. WINDS BCMG LGT/VAR.
FRI...CHC MVFR CIGS. WINDS SW 5-10 KTS BCMG NW 15-20G25 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY FROM 6 AM THIS MORNING TO 9 PM CST THIS
EVENING FOR MNZ041-042-047>049-054>058-064>067.
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR MNZ043>045-050>053-059>063-068>070.
WI...WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR WIZ014-023-024.
WINTER WEATHER ADVISORY FROM NOON TODAY TO MIDNIGHT CST TONIGHT
FOR WIZ015-016-025>028.
&&
$$
UPDATE...BORGHOFF
SHORT TERM...MPG
LONG TERM...JLT
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
323 AM CST TUE FEB 10 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 322 AM CST TUE FEB 10 2015
LOW PRESSURE ACROSS SCNTL SD IS EXPECTED TO CLEAR THE FCST AREA
OF LOW CLOUDS AND FOG BY 15Z THIS AM. FOG PRODUCTION IN THE DENSE
FOG ADVISORY AREA HAS BE BEEN LIMITED BY MIXING FROM STRONG SFC
WINDS AND POOR RADIATION FROM A BATCH OF MID LEVEL CLOUDS ALOFT.
THE RAP...ETAL MODELS INDICATES FAIRLY STRONG WEST WINDS WILL
DEVELOP BY 12Z SCOURING THE AREA OF MOISTURE AND SHUNTING THE FOG
EAST. THUS THE PROBABILITY OF DENSE FOG APPEARS LOW IN ALL SOLNS.
THE RAP WAS THE WARMEST MODEL AND WAS USED FOR THE TEMPERATURE
FORECAST TODAY FOR HIGHS IN THE UPPER 50S TO MID 60S. NORTHWEST
WINDS WILL BE INCREASING TO 15 TO 25 MPH IN THE WAKE OF THE SFC LOW
ACROSS SD. A TANDEM LOW ACROSS ERN MT WILL MOVE INTO CNTL ND THIS
AFTN AND SEND A COLD FRONT TOWARD NRN NEB. THE MODELS SHOW WEAK
CONVERGENCE AROUND THE LEE SIDE OF THE BLACK HILLS AS THE FRONT
APPROACHES AND THIS MIGHT BE ENOUGH FOR SPRINKLES ACROSS NRN
SHERIDAN COUNTY AND WRN CHERRY COUNTY. THE HRRR...GEM REGIONAL AND
RAP SUPPORT THIS RAIN CHANCE ALBEIT NON-MEASURABLE.
NORTHWEST WINDS SHOULD REMAIN STRONG TONIGHT AS AN ARCTIC COLD FRONT
MOVES THROUGH THE FCST AREA. THE MODELS SHOW WIND SPEEDS INCREASING
FROM 06Z ONWARD ACROSS THE NORTH AND H850MB TEMPERATURES FALLING TO
AROUND -7C BY MORNING WHICH MIGHT SUPPORT LOWS IN THE LOWER 20S
NORTH AND WARMER READINGS IN THE MID AND UPPER 20S TO NEAR 30 SOUTH.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 322 AM CST TUE FEB 10 2015
PRIMARY FORECAST CONCERNS FOR THIS PORTION OF THE FORECAST PERIOD
DEAL WITH TEMPERATURES THROUGHOUT...THEN WITH CHANCES FOR SNOW FOR
EARLY NEXT WEEK.
MODELS ARE IN GOOD AGREEMENT FOR MUCH OF THE FORECAST PERIOD WITH
ONLY MINOR DETAILS SEEN TO IMPACT THE FORECAST. THAT BEING
SAID...EVEN SOME MINOR DIFFERENCES COULD HAVE AN IMPACT ON THE
SENSIBLE WEATHER...MAINLY THE CLOUD COVER AND WINDS...WHICH IN TURN
CAN IMPACT THE TEMPERATURE FORECAST.
THE PERIOD BEGINS ON WEDNESDAY...WITH THE UPPER LEVEL SHORTWAVE
TROUGH WHICH IS NOW OVER THE NORTHWEST TERRITORIES DIGGING SOUTH
INTO THE UPPER MISSISSIPPI RIVER VALLEY REGION. THIS WILL PUSH A
GOOD COLD FRONT THROUGH THE REGION BY 12Z WEDNESDAY. THE TRACK OF
THE MAIN PV ANOMALY EMBEDDED IN THE SHORTWAVE STAYS WELL NORTH AND
EAST OF THE LOCAL AREA BUT THIS WILL LIKELY STILL ENHANCE THE
DOWNWARD MOTION/SUBSIDENCE...DRYING AND COLD AIR ADVECTION DURING
THE DAY TO AT LEAST HELP THE LOW LEVEL MIXING AND BRING ABOUT BREEZY
NORTHWEST WINDS. WITH THE COLD AIR ADVECTION BEHIND THE
FRONT...WEDNESDAY WILL BE QUITE A BIT COOLER THAN WHAT HAS BEEN
EXPERIENCED OVER THE PAST FEW DAYS...WITH HIGHS NEAR NORMAL MOST
PLACES. THE MODELS ARE SHOWING SOME WARMING ALOFT BY THE END OF THE
DAY WEDNESDAY WHICH COULD LEAD TO SLIGHTLY WARMER TEMPERATURES OVER
SOUTHWEST NEBRASKA. THE FORECAST WILL KEEP MID 40S FOR THESE AREAS
WITH LOW 30S OVER NORTH CENTRAL NEBRASKA ON WEDNESDAY.
THE SURFACE HIGH BEHIND THE SYSTEM BUILDS SOUTH INTO THE NORTHERN
PLAINS WEDNESDAY NIGHT...THEN INTO THE MISSISSIPPI RIVER VALLEY ON
THURSDAY. WITH THE COLD AIR ASSOCIATED WITH THE SURFACE
HIGH...TEMPERATURES WILL BE FAIRLY COLD WEDNESDAY NIGHT. THE COLDEST
AIR ALOFT WILL REMAIN ACROSS EASTERN NEBRASKA AND AS THOSE LOCATIONS
WILL BE CLOSER TO THE CENTER OF THE HIGH...WINDS WILL BE LIGHTER
WHICH SHOULD PROMOTE BETTER RADIATIONAL COOLING. FURTHER
WEST...RETURN FLOW SOUTHERLY WINDS SET UP AND ALTHOUGH WILL BE
LIGHT...ARE NOT EXPECTED TO COMPLETELY DROP OFF. THESE CONDITIONS
WILL CREATE A DECENT TEMPERATURE GRADIENT ACROSS THE FORECAST
AREA...FROM THE LOW SINGLE DIGITS TO AROUND 20 DEGREES.
FOR THURSDAY...THE NAM IS A BIT QUICKER THAN THE REMAINDER OF THE
MODEL SOLUTIONS WITH A WARM FRONT MOVING INTO NEBRASKA ON THURSDAY.
TIMING OF THIS FRONT WILL MAKE A DIFFERENCE IN TEMPERATURES DURING
THE AFTERNOON AS 850MB TEMPERATURES INCREASE TO AROUND 10C...WHILE
WEST-NORTHWEST FLOW AT THE SURFACE WILL HELP TO ENHANCE THE MIXING
POTENTIAL AND HELP WARM THINGS UP. HOWEVER...IF THE FRONT IS
SLOWER...COOLER TEMPERATURES WILL BE MAINTAINED THROUGH THE DAY. FOR
THE FORECAST...DID INCREASE HIGHS OVER THE WESTERN PART OF THE
FORECAST AREA AS CONFIDENCE IS HIGHER ON A BIT FASTER MOVEMENT AND
WITH A WARM BIAS THAT HAS BEEN SEEN LATELY IN OBSERVATIONS.
BY THIS POINT IN TIME...THE UPPER LEVEL FLOW ACROSS THE CONUS WILL
BE QUITE AMPLIFIED WITH A DEEP TROUGH OVER THE EAST COAST AND A
STRONG RIDGE OVER THE WESTERN CONUS. THIS PUTS THE LOCAL AREA WITHIN
NORTHWEST FLOW WHICH WILL BRING MULTIPLE SHORTWAVE TROUGHS ACROSS
THE AREA THROUGH THE REMAINDER OF THE FORECAST PERIOD. WHILE
MOISTURE WITH THE MAJORITY OF THESE SYSTEMS STAYS WELL NORTH OF THE
AREA TO KEEP THE FORECAST DRY...DESPITE PERIODS OF STRONGER LIFT.
WHAT WILL OCCUR IS LIKELY A BACK AND FORTH TREND FOR TEMPERATURES.
FRIDAY AND SUNDAY LOOK LIKE WARMER DAYS...WHILE SATURDAY AND MONDAY
WILL BE COOLER AS THE AREA WILL SIT IN THE WAKE OF WEAK SYSTEMS WITH
COLD AIR ADVECTION TO WORK WITH.
THE NEXT CHANCES FOR MEASURABLE PRECIPITATION WILL COME ON MONDAY.
THE UPPER LEVEL PATTERN DAMPENS OUT WITH MORE BROAD WEST TO
NORTHWEST FLOW IN PLACE. THE MODELS CONTINUE TO BE IN DECENT
AGREEMENT THIS FAR OUT BRINGING A WEAK SHORTWAVE TROUGH ACROSS
NEBRASKA AND SOUTH DAKOTA. THE MODELS ARE SHOWING A NEARLY COUPLED
RIGHT OVER-TOP OF THE FORECAST AREA WHICH SHOULD LEAD TO STRONGER
LIFT OVER THE AREA. IN ADDITION...DEEP LAYER MOISTURE INCREASES SO
AT THIS TIME WILL CONTINUE WITH MENTION OF PRECIPITATION FOR EARLY
IN THE WEEK. WITH COLD AIR ADVECTION THROUGH THE DAY
MONDAY...SOUNDINGS AND TEMPERATURE PROFILES WOULD INDICATE THE
PRECIPITATION WILL FALL AS SNOW SO ONLY HAVE THAT MENTION IN THE
FORECAST AT THIS TIME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1141 PM CST MON FEB 9 2015
FOR THE KLBF TERMINAL...EXPECT MOSTLY CLEAR SKIES OVER THE NEXT 24
HOURS. SOME LOW CLOUDS MAY IMPACT THE VICINITY OF THE KLBF
TERMINAL...MAINLY TO THE EAST OF THE FIELD WITH CIGS UNDER 1000 FT
AND VISBYS BLO 1SM. FOR NOW WILL LEAVE OUT THE MENTION OF LOW
CLOUDS AS THEY SEEM TO BE REMAINING STATIONARY JUST EAST OF THE
FIELD. FOR THE KVTN TERMINAL...CLEAR TO PARTLY CLOUDY SKIES ARE
EXPECTED THROUGH TUESDAY AFTERNOON WITH CIGS AROUND 25000 FT AGL.
CIGS WILL LOWER TO 10000 FT AGL AND THEN 5000 FT AGL TUESDAY
EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...BROOKS
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
257 AM CST TUE FEB 10 2015
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 255 AM CST TUE FEB 10 2015
LATEST MODELS IN AGREEMENT GOING FCST CONSISTING OF DRY CONDITIONS
LOOKS ON TRACK HEADING INTO THIS WEEKEND...THUS LEAVING TEMPS THE
MAIN ISSUE.
MODELS PROG NEAR ZONAL FLOW WILL EVOLVE OVER THE NEXT SEVERAL DAYS
TO A MORE AMPLIFIED PATTERN...LEADING TO A NOTICEABLE TEMP CHANGE
AS A SIGNIFICANT COLD AIR INTRUSION SWEEPS INTO THE CNTRL/ERN
CONUS. GFS/ECM/CMC METEOGRAMS IN GOOD AGREEMENT SHOWING THE
LEADING EDGE OF THE FRONT MAKING ITS WAY INTO THE OMAHA METRO
SOMETIME AROUND MIDNIGHT TONIGHT FOLLOWED BY A RE-ENFORCING SHOT
OF CAA COMING WED NIGHT.
FOR TODAY...HIGHS IN MID 40S EAST/MID 50S WEST STILL LOOK
REASONABLE FOLLOWED BY LOW/MID 30S WED...AND LOW/MID 20S THURS.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 255 AM CST TUE FEB 10 2015
EXT PDS START OFF WITH REBOUNDING TEMPS ON FRIDAY FOLLOWED BY A
ROLLER COASTER RIDE OF TEMPS THRU EARLY NEXT WEEK. THE COLD FRONT
MOVING EARLY NEXT WEEK WILL ALLOW FOR POSSIBLE PCPN OVER THE CWA
MON/MON NIGHT. PCPN TYPE FCST LOOKS A BIT TRICKY AS IT APPEARS THAT
ENOUGH CAA TO MAKE CHANGE OVER FROM LIQUID TO FROZEN WILL NOT COME
UNTIL LATE IN THE DAY. THIS FAR OUT THOUGH...SEE NO NEED TO GET INTO
DETAILS SO WILL JUST GO WITH RA/SN MIX NORTH AND RA SOUTH...THEN
SLGT SN CHC MON NIGHT.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1120 PM CST MON FEB 9 2015
LOW CLOUDS SHOULD PREVAILS OVERNIGHT. EXPECT A GENERAL DOWNWARD
TREND OF VBSYS THROUGH ABOUT 14Z...WITH WINDS INCREASING SLIGHTLY.
RECENT RAP MODEL RUNS SUGGEST THE LOW CLOUDS WILL BREAK UP LATE
MORNING OR EARLY AFTN AT KOFK AND KLNK...THEN BY MID AFTN AT
KOMA. WINDS WILL SHIFT TO THE NORTHWEST AT KOFK BY 00Z WED AT
KOFK...AND 02Z TO 04Z AT KOMA AND KLNK.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...DEE
LONG TERM...DEE
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1141 PM CST MON FEB 9 2015
.SYNOPSIS...
ISSUED AT 254 PM CST MON FEB 9 2015
AT H5 TROUGH FROM GREAT LAKES INTO FLORIDA PANHANDLE WITH
ASSOCIATED PRECIPITATION ALL ALONG THE EASTERN SEABOARD. RIDGE
INTO THE NORTHERN PLAINS WITH FAIRLY STRONG WAVE MOVING ACROSS THE
PACIFIC NORTHWEST.
&&
.UPDATE...
ISSUED AT 857 PM CST MON FEB 9 2015
RELEASED A SECOND UPDATE TO BETTER DEPICT HOW FAR WEST THE FOG
WILL MAKE IT INTO THE OVERNIGHT. BASED ON THE LATEST HRRR AND
NAM12...00Z VERSION...HAVE THE FOG GOING AS FAR WEST AS A LINE
FROM CURTIS...TO ARNOLD...TO NEAR VALENTINE. BASED ON OBS AT ONEILL
AND ORD...DECIDED TO HOIST A DENSE FOG ADVISORY FOR PORTIONS OF
THE EASTERN SANDHILLS AND PORTIONS OF NORTH CENTRAL NEBRASKA. THIS
WILL BE IN EFFECT UNTIL 9 AM CST TUESDAY MORNING. FOR LOCATIONS
ALONG THE WESTERN PERIPHERY OF THE FOG...THIS SHOULD BEGIN TO MOVE
SLOWLY EAST OVERNIGHT AS SURFACE WINDS SHIFT AROUND TO THE
SOUTHWEST AND WEST AS LOW PRESSURE ENTERS SOUTH DAKOTA.
UPDATE ISSUED AT 752 PM CST MON FEB 9 2015
JUST RELEASED AN UPDATED FORECAST TO ADDRESS THE FOG AND STRATUS
ACROSS EASTERN PORTIONS OF THE FORECAST AREA. LOOKING AT THE
HRRR...LATEST NAM12 SOLN AND SREF DATA...DECIDED TO PUSH FOG
FURTHER WEST UP TO THE HIGHWAY 83 CORRIDOR THIS EVENING. THE
MODELS DO SHIFT THIS EAST OVERNIGHT AS THE LOW LEVEL WINDS SHIFT
TO THE WEST...SO FOG WILL PEAK AROUND MIDNIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 254 PM CST MON FEB 9 2015
MAIN FORECAST CONCERN FOR THE OVERNIGHT REVOLVES AROUND THE WESTWARD
RETURN OF STRATUS AND/OR FOG. THE NAM MODEL IS ONCE AGAIN THE MOST
BULLISH WITH REDUCED VISIBILITY...BRINGING DENSE FOG AS FAR WEST AS
THE HIGHWAY 83 CORRIDOR. THE HRRR SEEMS TO BE A GOOD COMPROMISE FOR
NOW...WHICH INDICATES FOG IN THE SAME GENERAL AREA AS SEEN EARLIER
TODAY. SURFACE LOW PRESSURE IS SHOWN TO MOVE EAST ACROSS SOUTHERN
SOUTH DAKOTA OVERNIGHT...DRAGGING A TROUGH THROUGH THE
SANDHILLS...SO AM EXPECTING A GREATER WESTWARD...OR
SOUTHWEST...TRAJECTORY OF THE LOWER TROPOSPHERIC WIND...WHICH WILL
DRAW DRY LOW LEVEL AIR BACK INTO THE REGION. THIS BOUNDARY IS SHOWN
TO BE ALONG OR NEAR HIGHWAY 281 BY 12Z TOMORROW. FOR THIS...WOULD
EXPECT SOME IMPROVEMENT IN VISIBILITY AND SKY COVER FROM WEST TO
EAST THROUGH THE OVERNIGHT HOURS AND THE STRATUS SHOULD ONLY BE
CONFINED TO OUR FAR EAST.
A WEAK UPPER LEVEL DISTURBANCE/PV ANOMALY WILL CROSS THE
CENTRAL/NORTHERN PLAINS OVERNIGHT PROVIDING FOR A LEAST A SLIGHT
CHANCE OF PRECIPITATION ACROSS OUR FAR NORTHEAST. THE MODELS ARE
KEYING ON THE GREATEST FORCING WELL NORTH OF THE FORECAST AREA...AND
WITH SATURATION CONFINED TO THE LOWER TROPOSPHERE...RAIN WILL BE
DIFFICULT. AM LEANING TOWARD A DRIZZLE POTENTIAL...OR VERY LIGHT
RAIN...IF PRECIPITATION WERE TO BE REALIZED. ANY LIFT IS QUICKLY
EAST OF THE FORECAST AREA BY 12Z TUESDAY...BEYOND THAT...THE REST OF
THE DAY APPEARS DRY.
TEMPERATURES OVERNIGHT WILL BE MILD AS WAA SPREADS EAST AHEAD OF THE
PASSING SURFACE TROUGH. FORECAST LOWS RANGE FROM THE UPPER 20S IN
THE RIVER VALLEYS...TO THE MID 30S ACROSS THE HEART OF THE SANDHILLS
WHERE GREATER MIXING IS ANTICIPATED. FOR TUESDAY...THE DISTURBANCE
WILL DRAW SLIGHTLY COOLER AIR ACROSS WEST CENTRAL NEBRASKA. HIGHS
WERE TRENDED ACCORDINGLY...WITH MOST LOCATIONS SEEING A DROP OF 5-7F
FROM WHAT WAS OBSERVED TODAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 254 PM CST MON FEB 9 2015
MODELS IN FAIR AGREEMENT IN MID TERM AND THEN HAVING SOME
VARIABILITY IN LONG TERM SOLUTIONS. TUESDAY NIGHT COOLER AIR
FILTERS IN ACROSS THE NORTHERN PLAINS INTO WESTERN NEBRASKA. WITH
THE UPPER RIDGE IN PLACE THE HIGH PRESSURE WILL BE MOVED FURTHER
EAST WITH A STATIONARY BOUNDARY FROM THE NORTHERN NEBRASKA
PANHANDLE INTO BROKEN BOW. WARMER 40S TO THE SOUTHWEST AND 30S TO
THE NORTHEAST. LOWS WEDNESDAY NIGHT QUITE COLD WITH MOSTLY CLEAR
SKIES AND LIGHT WINDS. SINGLE DIGITS ONEILL AND LOW 20S OVER
SOUTHWEST NEBRASKA. SOUTHERLY WINDS THURSDAY WILL MODERATE
TEMPERATURES SOME WHAT ON THE BACKSIDE OF THE SURFACE HIGH. MILD
NIGHT THURSDAY NIGHT WITH RETURN FLOW. FRIDAY TEMPERATURES REBOUND
INTO THE 40S NORTH AND 50S SOUTH. A DRY BACKDOOR COLD FRONT WILL
MOVE ACROSS THE FORECAST AREA FRIDAY NIGHT INTO SATURDAY WITH
HIGHS ON SATURDAY RANGING FROM THE 20S ONEILL TO MID 40S IMPERIAL.
TEMPERATURES REBOUND SUNDAY WITH 40S NORTH AND 50S SOUTH IN RETURN
FLOW. INCREASING MOISTURE ACROSS THE SOUTHERN PLAINS SUNDAY AND AN
ARCTIC COLD FRONT MOVING SOUTH ACROSS THE NORTHERN PLAINS WILL SEE
A RETURN TO SNOW IN THE FORECAST SUNDAY NIGHT INTO MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1141 PM CST MON FEB 9 2015
FOR THE KLBF TERMINAL...EXPECT MOSTLY CLEAR SKIES OVER THE NEXT 24
HOURS. SOME LOW CLOUDS MAY IMPACT THE VICINITY OF THE KLBF
TERMINAL...MAINLY TO THE EAST OF THE FIELD WITH CIGS UNDER 1000 FT
AND VISBYS BLO 1SM. FOR NOW WILL LEAVE OUT THE MENTION OF LOW
CLOUDS AS THEY SEEM TO BE REMAINING STATIONARY JUST EAST OF THE
FIELD. FOR THE KVTN TERMINAL...CLEAR TO PARTLY CLOUDY SKIES ARE
EXPECTED THROUGH TUESDAY AFTERNOON WITH CIGS AROUND 25000 FT AGL.
CIGS WILL LOWER TO 10000 FT AGL AND THEN 5000 FT AGL TUESDAY
EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM CST TUESDAY FOR NEZ006-007-009-010-
028-029.
&&
$$
UPDATE...CLB
SYNOPSIS...POWER
SHORT TERM...JACOBS
LONG TERM...POWER
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1121 PM CST MON FEB 9 2015
.SHORT TERM...(TONIGHT THROUGH THURSDAY)
ISSUED AT 146 PM CST MON FEB 9 2015
LOW CLOUDS AND PATCHY FOG CONTINUES TO BLANKET THE REGION THIS
AFTERNOON AS AN AREA OF SFC HIGH PRESSURE REMAINS OVERHEAD. THIS
HAS KEPT TEMPERATURES FAIRLY COOL TODAY IN ADDITION TO LIGHT
SOUTHEASTERLY SFC WINDS. AN UPPER LEVEL RIDGE AXIS WAS OVER THE
HIGH PLAINS REGION THIS AFTERNOON WITH A TROUGH OVER THE WEST
COAST. A WEAK SHORTWAVE WAS MOVING OVER THE FRONT SIDE OF THE
RIDGE ACROSS SOUTHEASTERN WYOMING WHERE A FEW LIGHTNING STRIKES
HAVE SHOWN UP. THIS WAVE WILL CONTINUE TO SLIDE EAST TOWARD THE
REGION OVERNIGHT AS SFC LOW PRESSURE MOVES ACROSS THE NORTHERN
PLAINS. BEST FORCING ASSOCIATED WITH THE SHORTWAVE WILL BE TO OUR
NORTH BUT WILL CONTINUE TO MAINTAIN A VERY SMALL POP OVERNIGHT
NEAR THE NEBRASKA/SOUTH DAKOTA BORDER AHEAD OF APPROACHING SFC
FRONT. WILL CONTINUE THE MENTION OF PATCHY FOG THROUGH THE
EVENING...WITH AREAS OF FOG MENTIONED FOR OUR WESTERN AREAS. HRRR
VISIBILITY PLOTS CONTINUE TO SHOW EXTENSIVE FOG ACROSS OUR WESTERN
COUNTIES. DO NOT SEE VISIBILITIES IMPROVING MUCH UNTIL SFC WINDS
COME AROUND TO THE SOUTH/SOUTHWEST LATE TONIGHT.
SFC COLD FRONT WILL SWING THROUGH THE FORECAST AREA LATE TUESDAY
BRINGING A MUCH COLDER AIRMASS INTO THE AREA. 850MB WINDS BEHIND
THE FRONT BY WED 06Z ARE ON THE ORDER OF 40-50KTS ACROSS OUR
NORTHERN COUNTIES. SHOULD SEE STRONG MOMENTUM TRANSFER TO THE
SURFACE SO DID BUMP UP WINDS TUE NIGHT/WED MORNING. BREEZY
CONDITIONS SHOULD CONTINUE INTO THE DAY WEDNESDAY AS ANOTHER
REINFORCING SHOT OF ARCTIC AIR SLIDES INTO THE AREA. THIS WILL
BRING WIND CHILLS DOWN TO THE -10 TO -15 RANGE...ESPECIALLY IN OUR
EASTERN COUNTIES. A 1040 MB HIGH WILL MOVE OVERHEAD ON THURSDAY
WHICH SHOULD KEEP HIGH TEMPS FAIRLY CHILLY IN THE 20S.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 146 PM CST MON FEB 9 2015
AS SOON AS RETURN FLOW BEGINS THURSDAY NIGHT IT IS ENDED BY YET
ANOTHER COLD FRONT DROPPING OUT OF THE PLAINS FOR THE WEEKEND.
THIS WILL BRING A BITTERLY COLD AIRMASS TO PORTIONS OF THE UPPER
MIDWEST. WE LOOK TO BE ON THE WESTERN EDGE OF THE VERY COLD AIR
AS A 1045 MB HIGH MOVES SOUTHEAST FROM THE DAKOTAS INTO CENTRAL
IOWA SATURDAY. WE WILL CONTINUE WITH A DRY FORECAST UNTIL WE GET
LATE INTO DAY 7. THE ECMWF AND GFS CONTINUE TO DROP PCPN INTO THE
NORTHERN AND CENTRAL PLAINS EARLY NEXT WEEK.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1120 PM CST MON FEB 9 2015
LOW CLOUDS SHOULD PREVAILS OVERNIGHT. EXPECT A GENERAL DOWNWARD
TREND OF VBSYS THROUGH ABOUT 14Z...WITH WINDS INCREASING SLIGHTLY.
RECENT RAP MODEL RUNS SUGGEST THE LOW CLOUDS WILL BREAK UP LATE
MORNING OR EARLY AFTN AT KOFK AND KLNK...THEN BY MID AFTN AT
KOMA. WINDS WILL SHIFT TO THE NORTHWEST AT KOFK BY 00Z WED AT
KOFK...AND 02Z TO 04Z AT KOMA AND KLNK.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...KERN
LONG TERM...KERN
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1150 PM CST MON FEB 9 2015
.UPDATE...
ISSUED AT 1150 PM CST MON FEB 9 2015
CURRENT HEADLINES IN GOOD SHAPE. THE LATEST WATER VAPOR IMAGERY
LOOP PLACES A WELL DEFINED SHORTWAVE TROUGH OVER SOUTHEAST ALBERTA
INTO SOUTH CENTRAL MONTANA. SURFACE ANALYSIS SHOWS LOW PRESSURE
NORTH OF BILLINGS MONTANA...IN LINE WITH THE 00Z NAM/GFS. SURFACE
LOW SLIDES TO NEAR KILLDEER/DICKINSON AREA BY 12Z TUESDAY AND
PASSING THROUGH THE JAMES RIVER VALLEY TUESDAY AFTERNOON. CURRENT
LOCAL/REGIONAL RADAR SHOWS PRECIPITATION ON TRACK ACROSS WESTERN
AND CENTRAL NORTH DAKOTA AND NO CHANGES TO THE PREVIOUS FORECAST.
WILL MONITOR ICE ACCUMULATIONS CLOSELY OVERNIGHT.
LOOKING AHEAD...A STRONG PRESSURE GRADIENT AND COLD AIR ADVECTION
DEVELOP TUESDAY AFTERNOON AND EVENING...BEHIND THE SURFACE LOW. EARLY
INDICATIONS PER BUFKIT SHOWS MOST LOCATIONS MAY TAP INTO 30KT TO
40KT WINDS AT THE VERY TOP OF THE MIXED LAYER. A WIND ADVISORY MAY
BE WARRANTED...BUT WITH CURRENT WINTER WEATHER ADVISORIES IN
PLACE...WILL LOOK MORE AT THIS AT THE NEXT UPDATE.
UPDATE ISSUED AT 952 PM CST MON FEB 9 2015
NO SIGNIFICANT CHANGES FOR THE LATE EVENING UPDATE. REFLECTIVITIES
CONTINUE TO INCREASE ACROSS WESTERN AND INTO CENTRAL NORTH DAKOTA.
REPORTS OF FREEZING RAIN IN WESTERN NORTH DAKOTA. ALSO NOTICED
SOME VERY LIGHT FREEZING RAIN AND ICE PELLETS AT WFO BISMARCK THIS
PAST HOUR. DID CANCEL THE DENSE FOG ADVISORY AS EXCEPT FOR
HETTINGER...VISIBILITIES HAVE IMPROVED TO AROUND A MILE OR GREATER
IN MOST AREAS IN THE ADVISORY. NO CHANGES TO CURRENT WINTER
WEATHER HEADLINES. WILL FRESHEN UP TEXT PRODUCTS SHORTLY.
UPDATE ISSUED AT 600 PM CST MON FEB 9 2015
NO CHANGES TO CURRENT WINTER WEATHER OR FREEZING RAIN ADVISORIES.
DID EXTEND THE DENSE FOG ADVISORY THROUGH 10 PM THIS EVENING.
STILL SURFACE REPORTS AND WEATHER CAMERAS SHOWING DENSE FOG. THINK
WITH THE SYSTEM MOVING IN THROUGH THE EVENING VISIBILITIES WILL
BEGIN TO IMPROVE. NO ADDITIONAL CHANGES AT THIS TIME. WILL TAKE A
CLOSER LOOK AT TEMPERATURES AND PRECIPITATION WITH NEXT UPDATE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 400 PM CST MON FEB 9 2015
THE UPCOMING MIXED PRECIPITATION EVENT HIGHLIGHTS THE SHORT TERM
FORECAST.
IN REGARDS TO HEADLINES...WILL LET THE DENSE FOG ADVISORY ACROSS
MUCH OF THE WEST AND CENTRAL CONTINUE THROUGH 00 UTC WITH
CONTINUED UPSLOPE SOUTHEASTERLY FLOW. OTHER THAN ADDING
SIOUX...GRANT...STARK AND HETTINGER COUNTIES TO THE FREEZING RAIN
ADVISORY...ALL OTHER WINTER HEADLINES REMAIN UNCHANGED.
IN GENERAL...OVERALL EXPECTATIONS FOR THE EVENT VARY LITTLE WITH
THIS FORECAST PACKAGE THAT UTILIZED THE 12 AND INCOMING 18 UTC
DETERMINISTIC AND ENSEMBLE SUITES COMPARED TO THE 06 AND 00 UTC
GUIDANCE. THE 18 THROUGH 20 UTC HRRR ITERATIONS LINE UP WELL WITH
RADAR ACROSS EASTERN MONTANA AND WILL WEIGH HEAVILY ON THESE
SOLUTIONS IN THE NEAR TERM...BLENDED TO THE GLOBAL 12 AND 18 UTC
SUITES THROUGH THE NIGHT. THIS SUPPORTS AN EXPANDED THREAT FOR
FREEZING RAIN INTO SOUTHWEST NORTH DAKOTA GIVEN SURFACE
TEMPERATURES THAT HAVE REMAINED BELOW FREEZING UNDER THE STRATUS.
FOLLOWED CLOSELY TO THE 19-20 UTC RAP AND 18 UTC NAM BUFR
SOUNDINGS FOR THE STRENGTH OF THE WARM LAYER ALOFT. AS ALWAYS IN
MIXED PRECIPITATION TYPES EVENTS...THIS VARIABLE IS THE MOST
UNCERTAIN. EXPECT THE WARM LAYER ALOFT TO SUPPORT LIQUID TO THE
SURFACE FROM NORTHWEST THROUGH SOUTH CENTRAL NORTH DAKOTA THROUGH
10-12 UTC...BEFORE A TRANSITION TO A SLEET AND SNOW MIX AND AN
EVENTUAL END TO PRECIPITATION WITH A DRY SLOT OVERTAKING THE AREA.
FOR LOCATIONS ALONG AND NORTH OF HIGHWAYS 2 AND
52....PRECIPITATION IS EXPECTED TO BE ALL SNOW...WITH A SLIGHT
CHANCE FOR FREEZING DRIZZLE GIVEN LOW LEVEL SATURATION WARMER
THAN -10 C UNTIL THE FULL COLUMN CAN SATURATE AND SUPPORT ICE
CRYSTALS TO THE GROUND. THE 18 UTC GFS/NAM HAVE BOTH COME IN WITH
HIGHER QPF...ESPECIALLY ACROSS THE JAMES RIVER VALLEY INTO THE
TURTLE MOUNTAINS IN THE 06-12 UTC TIME FRAME. THIS TREND WILL HAVE
TO BE MONITORED IN THE 00 UTC RUNS...AS THIS WOULD LEAD TO HIGHER
SNOWFALL...AND POSSIBLE GREATER ICE ACCUMULATIONS IN THE SOUTHERN
JAMES RIVER VALLEY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 410 PM CST MON FEB 9 2015
...THE MAIN IMPACT IN THE LONG TERM IS COLD...
TUESDAY`S SYSTEM WILL DEPART THE REGION BY LATE TUESDAY NIGHT.
SCATTERED LIGHT SNOW WILL DIMINISH THROUGH THE EVENING HOURS WITH
LITTLE TO NO ADDITIONAL ACCUMULATION EXPECTED.
THE REST OF THE LONG TERM FORECAST LOOKS RATHER COLD ACROSS THE
EAST AND MILD ACROSS THE SOUTHWEST. A COLD AND DRY ARCTIC AIRMASS
WILL ENTER WEDNESDAY INTO THURSDAY. A STRONG SURFACE HIGH WILL
SETTLE ACROSS THE AREA THURSDAY MORNING...WHICH COULD LEAD TO VERY
COLD TEMPERATURES...AROUND 20 BELOW...ACROSS NORTH CENTRAL NORTH
DAKOTA.
A WARM FRONT IS THEN EXPECTED TO ENTER WESTERN NORTH DAKOTA
THURSDAY AFTERNOON AND EVENING WHICH SHOULD BRING MUCH WARMER
TEMPERATURES WESTERN NORTH DAKOTA. OVERALL THE LONG TERM LOOKS
RATHER DRY...WITH A FEW FLURRIES POSSIBLE THURSDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1150 PM CST MON FEB 9 2015
LIFR TO VLIFR CIGS AND IFR/LIFR VSBYS WILL DOMINATE THE TERMINALS
THROUGH TUESDAY MORNING. A WINTRY MIX OF LIGHT FREEZING RAIN AND
SNOW WILL ALSO IMPACT THE TERMINALS MONDAY NIGHT AND TAPER OFF FROM
WEST TO EAST THROUGH 18Z TUESDAY. GUSTY NORTHWEST WINDS TO 30KT WILL
TAKE CONTROL TUESDAY AFTERNOON THROUGH TUESDAY EVENING. CIGS WILL
LIFT TO MVFR BY MID TO LATE TUESDAY AFTERNOON AND REMAIN THERE
THROUGH THE END OF THE TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY UNTIL NOON CST /11 AM MST/ TUESDAY FOR
NDZ019>022-034>036-042-045>047-050.
FREEZING RAIN ADVISORY UNTIL 6 AM CST /5 AM MST/ TUESDAY FOR
NDZ001-009-010-017-018-033-041.
WINTER WEATHER ADVISORY UNTIL NOON CST TUESDAY FOR NDZ002-003-
011.
WINTER WEATHER ADVISORY UNTIL 6 PM CST TUESDAY FOR NDZ004-005-
012-013-023-025-037-048-051.
&&
$$
UPDATE...KS
SHORT TERM...AJ
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1144 PM CST MON FEB 9 2015
.UPDATE...
ISSUED AT 1143 PM CST MON FEB 9 2015
UPDATED POPS FOR SLOWER PRECIP MOVEMENT INTO THE AREA FOR THE REST
OF THE NIGHT. SOME FREEZING DRIZZLE HAS DEVELOPED AHEAD OF MAIN
SYSTEM. WILL INTRODUCE FREEZING DRIZZLE MAINLY OVER THE SOUTH AND
EAST OVERNIGHT.
UPDATE ISSUED AT 1004 PM CST MON FEB 9 2015
TEMPS CONTINUE TO RISE SLOWLY THIS EVENING. BIS AND ABR OBSERVED
SOUNDINGS INDICATED A SHALLOW MOIST LAYER BELOW 875 HPA WITH A SHARP
INVERSION AT 875 HPA. ALSO A DRY LAYER FROM 875 UP TO 500/550 HPA.
COMPARING OBSERVED SOUNDING WITH THE RUC, THE RUC APPEARED TO CATCH
THE WARM AIR ALOFT BEST THIS EVENING. SOME FREEZING PRECIP WILL BE
POSSIBLE OVER THE FAR SOUTHWEST ZONES LATER TONIGHT. NO OTHER
CHANGES MADE.
UPDATE ISSUED AT 700 PM CST MON FEB 9 2015
WILL TWEAK WINDS A BIT FOR TONIGHT. OTHERWISE LITTLE CHANGE TO THE
CURRENT FORECAST AT THIS UPDATE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 345 PM CST MON FEB 9 2015
WATER VAPOR IMAGERY DEPICTS A COUPLE STRONG UPPER WAVES THAT WILL
AFFECT THE REGION. MODELS ALL AGREE THAT A BAND OF MODERATE TO
HEAVY PRECIPITATION WILL MOVE THROUGH THE REGION LATER TONIGHT INTO
TUESDAY. HOWEVER...EACH SOLUTION HAS ITS OWN IDEA WITH REGARDS TO
P-TYPE...AND QPF AMOUNTS. GIVEN THE FACT THAT THERE WILL BE TWO
WAVES...AND THE INTERACTION AND EXACT TIMING OF THESE WAVES WILL
AFFECT THE DETAILS...THE UNCERTAINTY AMONG THE MODELS MAKES
SENSE. WITH THAT SAID...ATTEMPTING TO DECIDE THE FORECAST
DETAILS...HEADLINES...AND THE OVERALL MESSAGE IS DIFFICULT.
SNOW AMOUNTS...THIS SYSTEM WILL BE MOSTLY A QUICK MOVING WARM AIR
ADVECTION EVENT. PWATS WILL BE HIGH (ABOVE 0.5 INCH)...AND THERE
WILL BE POCKETS OF STRONGER FORCING JUST AHEAD OF EACH UPPER WAVE.
SNOW RATIOS WILL BE LOWER...AND GIVEN THE AVERAGE QPF AMONG THE
MODELS MOST AREAS WILL LIKELY RECEIVE 0.20 TO 0.30 INCHES PRECIP.
WHERE ALL SNOW OCCURS...THIS WOULD LEAD TO 2-4 INCHES...WHICH
WOULD OCCUR IN A SHORT PERIOD OF TIME GIVEN THE EXPECTED
INTENSITY. WITH THAT SAID...IN THOSE POCKETS OF STRONGER FORCING
SLIGHTLY HIGHER SNOWFALL AMOUNT UP TO 5 INCHES SHOULD BE
POSSIBLE.
FREEZING RAIN/SLEET POTENTIAL...MOST GUIDANCE INDICATE A STRONGER
SIGNAL FOR FREEZING RAIN ACROSS A PORTION OF SOUTHEAST NORTH
DAKOTA. THE MAIN QUESTION IS...GIVEN THE STRENGTH OF THE UPPER
WAVE...WILL THE ABOVE FREEZING WARM LAYER ALOFT ADVECT FURTHER
NORTH/EAST THAN EXPECTED? THE ANSWER IS MOST LIKELY YES...BUT HOW
FAR? DID ADJUST FREEZING RAIN/SLEET CHANCES TO ACCOUNT FOR THIS
POSSIBILITY (JUST SOUTH OF DEVILS LAKE AND INTO THE SOUTHERN RED
RIVER VALLEY)...AND ATTEMPTED TO MESSAGE THESE CHANCES
APPROPRIATELY. SNOW AMOUNTS IN THESE AREAS WILL DEPEND ON WHEN/IF
A SWITCH OVER TO SNOW OCCURS...AND ICE/SNOW AMOUNTS WILL NEED TO
BE REFINED ONCE MORE CONFIDENCE IS OBTAINED.
GIVEN THE ABOVE EXPECTED CONDITIONS...ISSUED A WINTER WEATHER
ADVISORY FOR THE ENTIRE AREA. SEGMENTED THE WSW BASED ON EXPECTED
IMPACTS AND TIMING. EVEN WITH LOW CONFIDENCE IN THE DETAILS...MOST
AREAS WILL RECEIVE 2-4 INCHES OF SNOW IN A BRIEF PERIOD OF
TIME...WHICH WILL INCREASE IMPACTS (NOT TO MENTION THE FREEZING
RAIN ACROSS A PORTION OF THE REGION).
A QUICK BURST OF STRONG LOW LEVEL COLD AIR ADVECTION WILL CAUSE A
PERIOD OF STRONGER NORTH WINDS TUESDAY EVENING...AND HUNG ONTO THE
ADVISORY FOR AREAS ALONG AND WEST OF THE VALLEY TO ACCOUNT FOR
BLOWING SNOW AND REDUCED VSBY.
WEAK WARM AIR ADVECTION THIS EVENING MAY LEAD TO FLURRIES/FZDZ.
MENTIONED THIS POSSIBLY IN THE GRIDS...AND IF IT DOES MATERIALIZE
THE START TIME OF THE ADVISORY MAY NEED TO BE MOVED UP. MOST
LIKELY LOCATION FOR FREEZING DRIZZLE WILL BE THE SOUTHERN VALLEY
WHERE THE AVERAGE TEMPERATURE OF THE LOW LEVEL SATURATED LAYER
WILL BE WARMER.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 345 PM CST MON FEB 9 2015
WEDNESDAY-THURSDAY...ANOTHER SURGE OF CAA WED AFTERNOON COULD LEAD
TO GUSTY WINDS AND BLOWING SNOW. OTHERWISE...ANTICIPATE SFC HIGH
PRESSURE AND BELOW NORMAL TEMPERATURES. WIND CHILL ADVISORY
CRITERIA POSSIBLE WED NIGHT.
THURSDAY NIGHT-MONDAY...PRETTY MUCH REMAIN IN NORTHWEST FLOW
ALOFT SO NO DIFFERENCES FROM PREVIOUS FEW DISCUSSIONS. MAIN
QUESTIONS REMAIN TIMING OR RESOLVING THE INDIVIDUAL WAVES AND
TEMPS. MODELS INDICATE WARM ADVECTION THU NIGHT WHICH COULD RESULT
IN SOME VERY LIGHT SNOW ACROSS THE EAST/NE. COULD BE A LITTLE
GUSTY ON FRI BEFORE THE SFC HIGH BUILDS IN FRI NIGHT. ANOTHER WAVE
BRINGS A SHOT AT SOME LIGHT PCPN SAT NIGHT OR SUNDAY FOLLOWED BY
ANOTHER SHOT MAINLY SOUTH OF THE FA ON MONDAY. QUITE A ROLLER
COASTER RIDE FOR TEMPS DEPENDENT ON THE TIMING OF THESE
SYSTEMS...WITH WARMER TEMPS AHEAD AND COOLER TEMPS BEHIND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1143 PM CST MON FEB 9 2015
IFR CONDITIONS ARE MOSTLY OVER THE ND SIDE OF THE RED RIVER. MVFR
ARE OVER THE MN SIDE. VFR CONDITIONS ARE OVER THE SOUTHEAST ZONES.
EXPECT CLEARING TO CONTINUE OVER THE SOUTHEAST ZONES. MVFR
CONDITIONS ON THE MN SIDE SHOULD MOVE SLOWLY NORTH. IFR CONDITIONS
OVER ND SIDE WILL SHIFT EAST OVERNIGHT AND TUE OVER MOST OF THE
AREA.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WINTER WEATHER ADVISORY FROM 3 AM TUESDAY TO 4 AM CST WEDNESDAY
FOR NDZ006-007-014-015-024-026-028>030-038-039-049-052>054.
WINTER WEATHER ADVISORY FROM 6 AM TUESDAY TO 4 AM CST WEDNESDAY
FOR NDZ008-016-027.
MN...WINTER WEATHER ADVISORY FROM 3 AM TUESDAY TO 4 AM CST WEDNESDAY
FOR MNZ002-003-029.
WINTER WEATHER ADVISORY FROM 9 AM TO 9 PM CST TUESDAY FOR MNZ005-
006-008-009-013>017-022>024-027-028-030>032-040.
WINTER WEATHER ADVISORY FROM 6 AM TUESDAY TO 4 AM CST WEDNESDAY
FOR MNZ001-004-007.
&&
$$
UPDATE...HOPPES
SHORT TERM...TG
LONG TERM...GODON/TG
AVIATION...HOPPES
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1005 PM CST MON FEB 9 2015
.UPDATE...
ISSUED AT 1004 PM CST MON FEB 9 2015
TEMPS CONTINUE TO RISE SLOWLY THIS EVENING. BIS AND ABR OBSERVED
SOUNDINGS INDICATED A SHALLOW MOIST LAYER BELOW 875 HPA WITH A SHARP
INVERSION AT 875 HPA. ALSO A DRY LAYER FROM 875 UP TO 500/550 HPA.
COMPARING OBSERVED SOUNDING WITH THE RUC, THE RUC APPEARED TO CATCH
THE WARM AIR ALOFT BEST THIS EVENING. SOME FREEZING PRECIP WILL BE
POSSIBLE OVER THE FAR SOUTHWEST ZONES LATER TONIGHT. NO OTHER
CHANGES MADE.
UPDATE ISSUED AT 700 PM CST MON FEB 9 2015
WILL TWEAK WINDS A BIT FOR TONIGHT. OTHERWISE LITTLE CHANGE TO THE
CURRENT FORECAST AT THIS UPDATE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 345 PM CST MON FEB 9 2015
WATER VAPOR IMAGERY DEPICTS A COUPLE STRONG UPPER WAVES THAT WILL
AFFECT THE REGION. MODELS ALL AGREE THAT A BAND OF MODERATE TO
HEAVY PRECIPITATION WILL MOVE THROUGH THE REGION LATER TONIGHT INTO
TUESDAY. HOWEVER...EACH SOLUTION HAS ITS OWN IDEA WITH REGARDS TO
P-TYPE...AND QPF AMOUNTS. GIVEN THE FACT THAT THERE WILL BE TWO
WAVES...AND THE INTERACTION AND EXACT TIMING OF THESE WAVES WILL
AFFECT THE DETAILS...THE UNCERTAINTY AMONG THE MODELS MAKES
SENSE. WITH THAT SAID...ATTEMPTING TO DECIDE THE FORECAST
DETAILS...HEADLINES...AND THE OVERALL MESSAGE IS DIFFICULT.
SNOW AMOUNTS...THIS SYSTEM WILL BE MOSTLY A QUICK MOVING WARM AIR
ADVECTION EVENT. PWATS WILL BE HIGH (ABOVE 0.5 INCH)...AND THERE
WILL BE POCKETS OF STRONGER FORCING JUST AHEAD OF EACH UPPER WAVE.
SNOW RATIOS WILL BE LOWER...AND GIVEN THE AVERAGE QPF AMONG THE
MODELS MOST AREAS WILL LIKELY RECEIVE 0.20 TO 0.30 INCHES PRECIP.
WHERE ALL SNOW OCCURS...THIS WOULD LEAD TO 2-4 INCHES...WHICH
WOULD OCCUR IN A SHORT PERIOD OF TIME GIVEN THE EXPECTED
INTENSITY. WITH THAT SAID...IN THOSE POCKETS OF STRONGER FORCING
SLIGHTLY HIGHER SNOWFALL AMOUNT UP TO 5 INCHES SHOULD BE
POSSIBLE.
FREEZING RAIN/SLEET POTENTIAL...MOST GUIDANCE INDICATE A STRONGER
SIGNAL FOR FREEZING RAIN ACROSS A PORTION OF SOUTHEAST NORTH
DAKOTA. THE MAIN QUESTION IS...GIVEN THE STRENGTH OF THE UPPER
WAVE...WILL THE ABOVE FREEZING WARM LAYER ALOFT ADVECT FURTHER
NORTH/EAST THAN EXPECTED? THE ANSWER IS MOST LIKELY YES...BUT HOW
FAR? DID ADJUST FREEZING RAIN/SLEET CHANCES TO ACCOUNT FOR THIS
POSSIBILITY (JUST SOUTH OF DEVILS LAKE AND INTO THE SOUTHERN RED
RIVER VALLEY)...AND ATTEMPTED TO MESSAGE THESE CHANCES
APPROPRIATELY. SNOW AMOUNTS IN THESE AREAS WILL DEPEND ON WHEN/IF
A SWITCH OVER TO SNOW OCCURS...AND ICE/SNOW AMOUNTS WILL NEED TO
BE REFINED ONCE MORE CONFIDENCE IS OBTAINED.
GIVEN THE ABOVE EXPECTED CONDITIONS...ISSUED A WINTER WEATHER
ADVISORY FOR THE ENTIRE AREA. SEGMENTED THE WSW BASED ON EXPECTED
IMPACTS AND TIMING. EVEN WITH LOW CONFIDENCE IN THE DETAILS...MOST
AREAS WILL RECEIVE 2-4 INCHES OF SNOW IN A BRIEF PERIOD OF
TIME...WHICH WILL INCREASE IMPACTS (NOT TO MENTION THE FREEZING
RAIN ACROSS A PORTION OF THE REGION).
A QUICK BURST OF STRONG LOW LEVEL COLD AIR ADVECTION WILL CAUSE A
PERIOD OF STRONGER NORTH WINDS TUESDAY EVENING...AND HUNG ONTO THE
ADVISORY FOR AREAS ALONG AND WEST OF THE VALLEY TO ACCOUNT FOR
BLOWING SNOW AND REDUCED VSBY.
WEAK WARM AIR ADVECTION THIS EVENING MAY LEAD TO FLURRIES/FZDZ.
MENTIONED THIS POSSIBLY IN THE GRIDS...AND IF IT DOES MATERIALIZE
THE START TIME OF THE ADVISORY MAY NEED TO BE MOVED UP. MOST
LIKELY LOCATION FOR FREEZING DRIZZLE WILL BE THE SOUTHERN VALLEY
WHERE THE AVERAGE TEMPERATURE OF THE LOW LEVEL SATURATED LAYER
WILL BE WARMER.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 345 PM CST MON FEB 9 2015
WEDNESDAY-THURSDAY...ANOTHER SURGE OF CAA WED AFTERNOON COULD LEAD
TO GUSTY WINDS AND BLOWING SNOW. OTHERWISE...ANTICIPATE SFC HIGH
PRESSURE AND BELOW NORMAL TEMPERATURES. WIND CHILL ADVISORY
CRITERIA POSSIBLE WED NIGHT.
THURSDAY NIGHT-MONDAY...PRETTY MUCH REMAIN IN NORTHWEST FLOW
ALOFT SO NO DIFFERENCES FROM PREVIOUS FEW DISCUSSIONS. MAIN
QUESTIONS REMAIN TIMING OR RESOLVING THE INDIVIDUAL WAVES AND
TEMPS. MODELS INDICATE WARM ADVECTION THU NIGHT WHICH COULD RESULT
IN SOME VERY LIGHT SNOW ACROSS THE EAST/NE. COULD BE A LITTLE
GUSTY ON FRI BEFORE THE SFC HIGH BUILDS IN FRI NIGHT. ANOTHER WAVE
BRINGS A SHOT AT SOME LIGHT PCPN SAT NIGHT OR SUNDAY FOLLOWED BY
ANOTHER SHOT MAINLY SOUTH OF THE FA ON MONDAY. QUITE A ROLLER
COASTER RIDE FOR TEMPS DEPENDENT ON THE TIMING OF THESE
SYSTEMS...WITH WARMER TEMPS AHEAD AND COOLER TEMPS BEHIND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 700 PM CST MON FEB 9 2015
MOSTLY MVFR CONDITIONS WERE ACROSS THE AREA. FOG LOOP INDICATED A
CLEARING FROM NEAR AXN TO SAZ. THE CLEARING WAS MOVING TO THE
WEST/NORTHWEST AT ABOUT 10 KNOTS. VFR CONDITIONS WERE OVER FAR
NORTHERN MN WITH CIGS BETWEEN 30 AND 35 HUNDRED FT. ELSEWHERE IFR
CONDITIONS WERE OVER BJI AND FSE AND THE FAR SOUTHWEST ZONES. EXPECT
SOME CLEARING TO MOVE INTO THE FAR SOUTHEAST ZONES. EXPECT IFR
CONDITIONS TO CONTINUE OVER BJI AND FSE AREAS AND MAY SHIFT TO THE
WEST THIS EVENING. IFR CONDITIONS OVER THE FAR SOUTHWEST ZONES NOT
EXPECTED TO MOVE MUCH.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WINTER WEATHER ADVISORY FROM 3 AM TUESDAY TO 4 AM CST WEDNESDAY
FOR NDZ006-007-014-015-024-026-028>030-038-039-049-052>054.
WINTER WEATHER ADVISORY FROM 6 AM TUESDAY TO 4 AM CST WEDNESDAY
FOR NDZ008-016-027.
MN...WINTER WEATHER ADVISORY FROM 3 AM TUESDAY TO 4 AM CST WEDNESDAY
FOR MNZ002-003-029.
WINTER WEATHER ADVISORY FROM 9 AM TO 9 PM CST TUESDAY FOR MNZ005-
006-008-009-013>017-022>024-027-028-030>032-040.
WINTER WEATHER ADVISORY FROM 6 AM TUESDAY TO 4 AM CST WEDNESDAY
FOR MNZ001-004-007.
&&
$$
UPDATE...HOPPES
SHORT TERM...TG
LONG TERM...GODON/TG
AVIATION...HOPPES
AREA FORECAST DISCUSSION
NWS TULSA OK
1117 PM CST MON FEB 9 2015
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
DECK OF LOW CLOUDS CONTINUES TO VERY SLOWLY SPREAD TOWARD THE WEST
BUT IT REMAINS UNCERTAIN JUST HOW FAR WEST IT WILL EXPAND TONIGHT.
INCREASING S COMPONENT TO CLOUD-LEVEL WINDS WILL ULTIMATELY HALT
ITS PROGRESS BUT NOT BEFORE AT LEAST A FEW HOURS OF MVFR CEILINGS
AT KROG/KXNA...LESS CERTAIN FOR KFYV. WILL ALSO SEE SOME REDUCED
VIS AT SOME SITES OVERNIGHT. OTHERWISE EXPECT VFR CONDITIONS TO PREVAIL.
&&
.PREV DISCUSSION... /ISSUED 853 PM CST MON FEB 9 2015/
DISCUSSION...
ANOTHER QUIET EVENING ACROSS THE FORECAST AREA. DECK OF LOW CLOUDS
THAT BACK-DOORED INTO OUR AREA THIS MORNING HAD RETREATED DURING
THE DAYTIME HOURS...BUT HAS SINCE SAGGED BACK TO THE SOUTHWEST
AGAIN. THE LATEST HRRR SHOWS SOME PENETRATION INTO FAR NE OK AND
NW AR...BUT ONLY TEMPORARILY. WE SHALL SEE. IT IS OFTEN DIFFICULT
FOR A CLOUD DECK TO BREAK UP AT NIGHT. I ALSO ADDED SOME FOG/CLOUD
COVER WESTWARD ALONG THE KS BORDER BASED ON PERSISTENT HRRR
FORECAST. SKY GRIDS MAY NEED CONTINUAL TWEAKING BASED ON WHAT THE
EXTENSIVE LOW CLOUD DECK TO OUR NORTHEAST DOES.
LACY
PREV DISCUSSION... /ISSUED 530 PM CST MON FEB 9 2015/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
FOR THE MOST PART VFR CONDITIONS WILL PREVAIL THROUGH THE
PERIOD. POSSIBLE EXCEPTIONS WILL BE THAT PARTS OF NW ARKANSAS AND
FAR NORTHERN OK COULD SEE PATCHY FOG LATER TONIGHT....AND AREA OF
LOW CLOUDS MAY SPREAD BACK WEST NEAR KS/MO BORDERS OVERNIGHT AS
LOW LEVEL WINDS SWITCH AROUND TO THE EAST THEN SOUTHEAST. BOTH
SCENARIOS BRING RISK OF MVFR CONDITIONS BETWEEN APPROX 06-15Z.
PREV DISCUSSION... /ISSUED 328 PM CST MON FEB 9 2015/
DISCUSSION...
SFC RIDGE AXIS OVERHEAD TODAY WITH GOOD EAST/WEST GRADIENT IN
AFTERNOON TEMPS. RIDGE TO SHIFT EASTWARD ON TUESDAY ALLOWING
WARMER TEMPS AND RETURN TO SOUTHERLY WINDS. PATCHY FOG MAY DEVELOP
TONIGHT BEFORE WINDS PICK UP OTHERWISE CLEAR SKIES WILL PREVAIL.
COLD FRONT TO PUSH THROUGH THE AREA ON WEDNESDAY WITH A SLIGHT
CHANCE OF SHOWERS FOR SE OK / WESTERN AR...WITH NOTICEABLY COOLER
TEMPS EXPECTED ON THURSDAY. A BRIEF WARM UP IS LIKELY ON FRIDAY
BEFORE AN EVEN STRONGER COLD FRONT SWEEPS THROUGH THE AREA PUSHING
TEMPS BELOW NORMAL FOR THE WEEKEND.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...99
LONG TERM....99
AVIATION...14
AREA FORECAST DISCUSSION
NWS NORMAN OK
1048 PM CST MON FEB 9 2015
.AVIATION...
06Z TAFS...AS TEMPERATURES CONTINUE TO FALL AND MOISTURE
INCREASES SLIGHTLY...EXPECT PATCHY FOG TO PERSIST AND POSSIBLY
EXPAND FROM NORTH CENTRAL THROUGH CENTRAL AND NORTHWESTERN
OKLAHOMA. BRIEF MVFR/IFR CIGS MAY OCCUR IN THESE
AREAS...ESPECIALLY FROM NOW THROUGH 13Z TUES. BKN CIGS MAY ALSO
DEVELOP AT KPNC...BUT SHOULD GENERALLY REMAIN NORTHEAST OF
REMAINING TERMINALS. VFR CONDITIONS SHOULD RETURN BY 15Z TUES...WITH
LIGHT EAST WINDS SHIFTING TO THE SOUTH AND BECOMING BREEZY BY 16Z
TO 18Z. A WEAK FRONT/WIND SHIFT WILL BRING A NORTHERLY WIND SHIFT
TO KGAG/KWWR BY 19Z. THIS WIND SHIFT WILL THEN SPREAD SOUTHWARD
THROUGH TOMORROW EVENING.
&&
.PREV DISCUSSION... /ISSUED 944 PM CST MON FEB 9 2015/
DISCUSSION...
ONLY MINOR UPDATES TO THE PACKAGE THIS EVENING. AN AREA OF
RESTRICTED VISIBILITY HAS DEVELOPED IN NORTHERN OKLAHOMA AND
PORTIONS OF KANSAS INCLUDING KPNC. ALTHOUGH RAP AND HRRR SUGGEST
THAT ANY AREAS OF SIGNIFICANT FOG WILL REMAIN NORTH OF OKLAHOMA...
HAVE ADDED THE MENTION OF PATCHY FOG IN NORTH CENTRAL OKLAHOMA
GIVEN THE CURRENT REDUCTION OF VISIBILITY. HAVE ALSO REDUCED THE
FORECAST CLOUD COVER IN NORTHWEST OKLAHOMA LATER TONIGHT.
PREV DISCUSSION... /ISSUED 539 PM CST MON FEB 9 2015/
AVIATION...
00Z TAFS...VFR CONDITIONS WILL PERSIST THROUGH AROUND 09Z.
THEREAFTER...SOME PATCHY FOG MAY REDUCE VSBYS TO 2 TO 5 SM FROM
CENTRAL THROUGH NORTHERN AND WESTERN OKLAHOMA. IFR CIGS MAY ALSO
OCCUR BRIEFLY AT KCSM/KGAG EARLY TUESDAY. WINDS WILL GRADUALLY
SHIFT FROM EAST TO SOUTHEAST THROUGH THE NIGHT...BECOMING GUSTY
EARLY TUESDAY. A WEAK FRONT WILL RESULT IN AT NORTHERLY WIND SHIFT
BY 18Z AT KGAG AND KWWR. VFR CONDITIONS SHOULD RETURN EARLY
THURSDAY TO ANY TERMINALS THAT SEE PATCHY FOG.
PREV DISCUSSION... /ISSUED 344 PM CST MON FEB 9 2015/
DISCUSSION...
VERY MILD WEATHER WILL CONTINUE ONE MORE DAY...BEFORE A STRONG
COLD FRONT SENDS TEMPERATURES TUMBLING BACK DOWN TOWARD THE
SEASONAL AVERAGE. MOISTURE WILL BE MEAGER WITH THE FRONT...SO RAIN
CHANCES WILL BE LOW.
THE TEMPERATURE ROLLER COASTER WILL CONTINUE WITH A WARMING TREND
THURSDAY AND FRIDAY...FOLLOWED BY ANOTHER STRONG COLD FRONT ON
SATURDAY. THEN...ANOTHER WARMING TREND...AND ANOTHER COLD FRONT
EARLY NEXT WEEK...JUST BEYOND THE REACH OF THIS FORECAST. EACH
COLD FRONT WILL BRING A COLDER AIRMASS THAN THE ONE BEFORE. NONE
OF THEM ARE LIKELY TO INVOLVE ENOUGH MOISTURE FOR SIGNIFICANT
PRECIPITATION.
WINDS BEHIND EACH COLD FRONT WILL BE FAIRLY STRONG AND GUSTY.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 41 69 43 55 / 0 0 0 10
HOBART OK 44 72 43 57 / 0 0 0 0
WICHITA FALLS TX 45 76 46 62 / 0 0 0 0
GAGE OK 41 68 37 53 / 0 0 0 10
PONCA CITY OK 35 63 39 50 / 0 0 0 10
DURANT OK 42 67 45 63 / 0 0 0 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
26/84
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
127 AM EST TUE FEB 10 2015
.SYNOPSIS...
IN THE WAKE OF A COLD FRONT...DRY HIGH PRESSURE WILL BUILD INTO THE
REGION ON TUESDAY AND LINGER THROUGH WEDNESDAY. AN ARCTIC COLD FRONT
WILL REACH THE MOUNTAINS ON THURSDAY WITH A COLD AIR MASS FILTERING
INTO THE REGION FRIDAY THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
120 AM EST TUESDAY UPDATE...POPS WERE RAISED INTO THE LIKELY TO
CATEGORICAL RANGE OVER THE WESTERN NC PIEDMONT INCLUDING THE
CHARLOTTE METRO AREA WHERE WIDESPREAD SHOWERS WERE OCCURRING AS A
CONSEQUENCE OF THE UPPER LVL LOW PRESSURE SLOWLY DRIFTING EASTWARD.
EXPECT THE PRECIP TO TAPER OFF BY AROUND DAYBREAK AS THE PRECIP
SHIELD ASSOCIATED WITH THE UPPER LOW PUSHES OFF TO THE EAST.
AS OF 825 PM...HAVE UPDATED THE FCST TO REMOVE MENTION OF THUNDER
AND INCREASE POPS ACRS THE ERN HALF OF THE CWFA TO LIKELY BASED ON
RADAR TRENDS. THE AXIS OF THE MID LVL SHORTWAVE TROF IS IN LINE WITH
THE BACK EDGE OF PRECIP. SO EXPECT POPS TO TAPER OFF FROM WEST TO
EAST THIS EVENING. THE EXCEPTION IS ALONG THE TN LINE...WHERE POPS
LINGER THRU THE OVERNIGHT. THE LATEST RAP 850 MB INITIALIZES THE 0C
LINE STILL BACK TO THE WEST. AND TEMPS IN THE MTNS ARE STILL IN THE
UPR 30S TO MID 40S. SO CHANGEOVER TO SNOW SHWRS HAS BEEN DELAYED.
LITTLE IF ANY ACCUMS ARE EXPECTED OVERNIGHT BEFORE SHWRS TAPER OFF
AROUND DAYBREAK TUESDAY.
AS OF 655 PM...NO SIGNIFICANT CHANGES TO THE PUBLIC FCST WITH THIS
UPDATE. TWEAKED TEMPS/DWPTS AGAIN WITH LATEST OBS. SKY/WIND/POP/WX
WERE ADJUSTED WITH LATEST GUIDANCE FOR THE 00Z TAFS. BASED ON RADAR
TRENDS...IT LOOKS LIKE THE THUNDER THREAT IS PRETTY MUCH OVER IN THE
UPPER SAVANNAH VALLEY.
AS OF 430 PM...THE POP TRENDS STILL LOOK ON TRACK. THERE ARE FEW
BREAKS IN THE CLOUDS ACRS GA AND WRN UPSTATE ON VIS SAT. CONVECTION
IS DEVELOPING WHERE THERE IS SOME INSOLATION...AND STILL MAY SEE AN
ISOLD TSTM OR TWO ACRS THE UPPER SAVANNAH VALLEY AND SRN UPSTATE
OVER THE NEXT COUPLE HOURS (LAPS CAPE IS UP TO 250 TO 600+ J/KG).
CANNOT RULE OUT SMALL HAIL/GRAUPEL WITH THE HEAVIEST
CONVECTION...GIVEN THE LOW FREEZING LEVELS...AND A FEW REPORTS IN
GA. I UPDATED THE TEMPS/DWPTS WITH THE LATEST OBS. TEMPS ARE RUNNING
COOLER THAN EXPECTED...GIVEN STUBBORN RAIN AND CLOUDS.
AS OF 210 PM EST...WATER VAPOR IMAGERY SHOWS A DIGGING UPPER LEVEL
SHORTWAVE OVER THE BASE OF THE SRN APPALACHIANS THIS
AFTERNOON...GRADUALLY ACQUIRING A MORE NEUTRAL TILT AS IT MOVES
EAST. DEEP LAYER DPVA AHEAD OF THIS WAVE IS CROSSING THE ERN HALF OF
THE FORECAST AREA THIS AFTN...WHILE ADDITIONAL SCT ACTIVITY DEVELOPS
BACK TO THE WEST UNDER THE COLD TROUGH ALOFT AND AHEAD OF THE
ASSOCIATED SFC COLD FRONT. A VERY FEW CLOUD TO CLOUD LIGHTNING
STRIKES WERE INDICATED EARLIER THIS AFTN...BUT THE CLOUD COVER HAS
KEPT LAPS SFC BASED CAPE VALUES LESS THAN 100 J/KG FOR ALL AREAS
EXCEPT THE EXTREME SRN PIEDMONT. WILL CONFINE ANY ISOLD THUNDER
MENTION GOING FORWARD TO SRN AND ERN SECTIONS THROUGH LATE AFTN.
SHEAR PROFILES REMAIN TOO WEAK FOR ANY SEVERE CONVECTION.
ANTICIPATE FROPA ACROSS THE MTNS THIS EVENING...BUT THEN THE
BOUNDARY WILL WASH OUT OVER THE PIEDMONT OR POSSIBLY GET HUNG UP
NEAR THE HIGHER TERRAIN OF THE SRN MTNS AND GRADUALLY DISSIPATE. THE
PASSING UPPER TROUGH WILL DEEPEN FURTHER TONIGHT...AND POSSIBLY CUT
OFF JUST EAST OF OUR FORECAST AREA...WITH STRONGER SFC WAVE
FORMATION LIKELY OUT OVER THE COASTAL PLAIN OVERNIGHT. THIS WILL
SLOW THE DEEP LAYER DRYING FROM THE WEST...AND LEAD TO A MORE
GRADUAL WEST TO EAST DROPOFF IN POPS. IN ADDITION...SUBFREEZING 850
MB TEMPS WILL ARRIVE ALONG THE SPINE OF THE SRN APPALACHIANS TOWARD
06Z. SCATTERED WESTERN MTNS SNOW SHOWERS OVERNIGHT COULD LEAD TO
VERY LIGHT ACCUMS IN THE TN BORDER COUNTIES...HOWEVER...THE LOW
LEVEL UPSLOPE FLOW WILL BE MORE NRLY THAN DESIRED FOR DECENT UPSLOPE
PRECIPITATION. CANNOT RULE OUT SOME LIGHT ICING GIVEN THE SHALLOW
MOISTURE PROFILES AND POSSIBLE LINGERING WARM NOSE...BUT RAIN/SNOW
IS PREFERRED BY THE CONSENSUS PROFILES.
FINALLY...WEAK DEFORMATION ZONE FORCING W OF THE COASTAL LOW...ALONG
WITH LINGERING 850 MB MOISTURE IN THE NRLY FLOW...WILL LIKELY ALLOW
CLOUDS TO PERSIST OVER THE WRN CAROLINAS THROUGH MUCH OF TUESDAY.
HOWEVER...NO FURTHER SHOWERS ARE EXPECTED THIS FAR W. TEMPERATURES
WILL BE NEAR CLIMATOLOGY...EXCEPT COOLER THAN CLIMO IN WRN NC.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY/...
AS OF 145 PM MONDAY...TUESDAY NIGHT AND WED SHOULD BE QUIET ACROSS
THE WESTERN CAROLINAS AND NE GA AS SHORT WAVE RIDGING DEVLOPS ACROSS
THE AREA. HOWEVER...THE FLOW WILL QUICKLY AMPLIFY ON THURSDAY AS A
SHARP UPPER TROUGH QUICKLY DIGS SE OUT OF CANADA WITH A LONG WAVE
TROUGH DEVELOPING OVER THE EASTERN U.S. ON THURSDAY. THE DIGGING
UPPER TROUGH WILL SPAWN A CLIPPER LOW WHICH IS FORECAST TO MOVE WELL
NORTH OF THE AREA...BUT IS ASSOCIATED COLD FRONT WILL MOVE ACROSS
THE FORECAST AREA ON THURSDAY. THE FRONT WILL BE MOISTURE STARVED SO
DESPITE THE RATHER IMPRESSIVE UPPER AIR DYNAMICS...LITTLE IN THE WAY
OF PRECIP WILL ACCOMPANY THE FRONT OUTSIDE THE MOUNTAINS EXCEPT
PERHAPS SOME SPRINKLES/FLURRIES WITH THE PASSAGE OF THE UPPER TROUGH
THU AFTERNOON. HOWEVER...THE DEVELOPING NW FLOW WILL SQEEZE OUT SOME
MAINLY UPSLOPE INDUCED SNOW SHOWERS IN THE MOUTNAINS ON THU...BUT
RIGHT NOW ACCUMULATIONS LOOK TO BE ON THE LIGHT SIDE EVEN THOUGH
FORECAST SOUNDINGS LOOK SOMEWHAT CONVECTIVE. THEREFORE...WOULD NOT
BE SURPRISED IF ADVISORY LEVEL SNOW ACCUMS RESULT BY LATE THU
ESPECIALLY IN THE NORTHERN MOUNTAINS. THE BIG STORY WILL BE THE
PLUNGING TEMPS. MAX TEMPS IN THE MOUNTAINS ON THURSDAY WILL OCCUR IN
THE EARLY MORNING THEN FALLING THROUGHOUT THE DAY AS 850 TEMPS FALL
WELL INTO THE NEGATIVE TEENS. OUTSIDE THE MOUNTAINS AS
USUAL...DOWNSLOPE FLOW WILL MITIGATE COLD ADVECTION INITIALLY BUT
WILL EVENTUALLY BE OVERWHELMED BY CAA IN THE AFTERNOON. MAX TEMPS
OUTSIDE THE MOUNTAINS LOOK TO OCCUR IN THE EARLY AFTEERNOON AND THEN
FALL OFF AS 850 TEMPS FALL INTO THE NEGATIVE LOWER TEENS BY 00Z FRI.
WINDS WILL ALSO INCREASE AND BECOME GUSTY ON THURSDAY BUT LOOK TO
REMAIN BELOW ADVISORY LEVELS AT THIS POINT. MAX TEMPS SHOULD BE NEAR
CLIMO ON WED AND THEN WELL BELOW CLIMO IN THE MOUNTAINS THU AND
ABOUT A CATEGORY BELOW EAST OF THE MOUNTAINS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 210 PM MONDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON FRIDAY
WITH A HIGHLY AMPLIFIED UPPER TROF AXIS RIGHT OVER THE CAROLINAS AND
STEEP UPPER RIDGING OVER THE WESTERN CONUS. OVER THE NEXT 24
HRS...THE TROF AXIS LIFTS TO THE NE HOWEVER WE WILL LIKELY REMAIN
UNDER BROAD UPPER TROFFING THRU MOST OF THE PERIOD. ON SAT...THE
TROF AMPLIFIES AGAIN AND BRINGS ANOTHER ROUND OF IMPRESSIVE PVA AND
COLD AIR OVER THE REGION. BY EARLY MON...THIS ENERGY LIFTS NE AND
HEIGHTS RISE AS THE UPPER PATTERN FLATTENS OUT. IT SHOULD BE NOTED
THAT THE OVERALL MODEL AGREEMENT FOR THE PERIOD LOOKS ESPECIALLY
GOOD.
AT THE SFC...SIGNIFICANT CAA WILL BE UNDERWAY BY LATE THURS/EARLY
FRI AS COLD CANADIAN HIGH PRESSURE PUSHES INTO THE REGION FROM THE
NW. OVER THE NEXT 24 HRS...A LOW IS EXPECTED TO DEVELOP OVER THE
GREAT LAKES AND DRIFT SE...YET ITS LOOKING LIKE MOST OF THE DEEPER
MOISTURE ASSOCIATED WITH THAT SYSTEM WILL REMAIN TO OUR NORTH. AS
THE LOW TRACKS EASTWARD...ANOTHER STRONG CANADIAN HIGH MOVES INTO
THE REGION ON SUNDAY BRINGING SOME OF THE COLDEST/DRIEST AIR OF THE
SEASON. THE HIGH IS EXPECTED TO REMAIN OVER THE AREA THRU NEW DAY 7
WHICH IS NEXT MONDAY. THE ONLY POPS I CARRY FOR THE PERIOD ARE SMALL
AREAS OF SLIGHT CHANCE OVER THE NORTHERN MTS LATE THURS/EARLY FRI
AND SAT. OTHERWISE...IT WILL BE DRY. MORE NOTEWORTHY WILL BE WELL
BELOW NORMAL TEMPS ON FRI AND SUN WITH EQUALLY DRY DEWPTS. THESE
TEMPS COUPLED WITH GUSTY WINDS COULD CAUSE SOME FIRE DANGER ISSUES
AND WIND CHILL CONCERNS EARLY FRIDAY AND SUNDAY...ESPECIALLY OVER
THE HIGHER ELEVATIONS.
&&
.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
AT KCLT...LIFR CIGS IN LIGHT SHOWERS WILL CONTINUE OVER THE NEXT
SEVERAL HOURS BEFORE THE PRECIP DRYING OUT BY AROUND 8Z WITH CIGS
LIFTING TO ABOUT 800FT RANGE. AN UPPER LOW WILL CONTINUE TO SLOWLY
MOVE EASTWARD THROUGH THE DAYBREAK...YIELDING N/NNELY FLOW AND IFR
CLOUDS. EXPECT GUSTY NNE WINDS OF 15-22KTS TO DEVELOP AND CIGS
SHOULD LIFT INTO THE MVFR LVL BY THIS MORNING AS SURFACE PRESSURE
GRADIENT TIGHTENS UP BEHIND THE DEPARTING LOW. AS DRY HIGH PRESSURE
FURTHER BUILDS IN...CIGS SHOULD RISE TO VFR LVL BY MIDDAY. GUSTY
WINDS SHOULD SUBSIDE BEYOND 22Z...BUT WILL REMAIN AROUND 7-10KT
RANGE.
ELSEWHERE...AREAS OF LIGHT SHOWERS OVER THE NC PIEDMONT AND PORTIONS
OF THE EASTERN UPSTATE SC SHOULD TAPER OFF OVER THE NEXT FEW HOURS
AS THE UPPER LOW ASSOCIATED WITH PRECIP SHIELD FURTHER MOVES OFF TO
THE EAST. AN INTRUSION OF DRY SLOT BEHIND THE DEPARTING LOW WILL
YIELD VFR CIGS ACROSS MUCH OF THE REGION OVERNIGHT EXCEPT KAVL WHERE
IFR/MVFR CLOUDS SHOULD LINGER AT LEAST THRU DAYBREAK. WINDS SHOULD
INCREASE THRU THE OVERNIGHT...BECOMING GUSTY AT TIMES BY EARLY THIS
MORNING AS PRESSURE GRADIENT TIGHTENS UP BETWEEN THE DEPARTING LOW
AND HIGH PRESSURE TO THE NW. EXPECT VFR CONDITIONS TO PREVAIL TODAY
UNDER THE INFLUENCE OF BUILDING HIGH PRESSURE. GUSTY WINDS OF
10-20KTS SHOULD DECREASE TO AROUND 5-10KT BY THE AFTERNOON.
OUTLOOK...DRYING CONDITIONS ARE EXPECTED LATE TUE THROUGH WED. A
COLD FRONT WILL CROSS THE REGION FROM THE NW ON THU...BUT WITH
LIMITED MOISTURE. BREEZY TO WINDY CONDITIONS ARE EXPECTED BEHIND THE
FRONT THU THROUGH FRI...WITH COLDER TEMPERATURES.
CONFIDENCE TABLE...
06-12Z 12-18Z 18-24Z 00-06Z
KCLT HIGH 80% MED 79% HIGH 97% HIGH 100%
KGSP MED 65% HIGH 92% HIGH 100% HIGH 100%
KAVL LOW 57% MED 73% HIGH 100% HIGH 100%
KHKY LOW 25% MED 65% HIGH 100% HIGH 100%
KGMU MED 63% HIGH 85% HIGH 100% HIGH 100%
KAND LOW 58% MED 74% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...CSH
NEAR TERM...ARK/HG/JOH
SHORT TERM...LG
LONG TERM...JPT
AVIATION...JOH
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
109 AM EST TUE FEB 10 2015
.SYNOPSIS...
IN THE WAKE OF A COLD FRONT...DRY HIGH PRESSURE WILL BUILD INTO THE
REGION ON TUESDAY AND LINGER THROUGH WEDNESDAY. AN ARCTIC COLD FRONT
WILL REACH THE MOUNTAINS ON THURSDAY WITH A COLD AIR MASS FILTERING
INTO THE REGION FRIDAY THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 825 PM...HAVE UPDATED THE FCST TO REMOVE MENTION OF THUNDER
AND INCREASE POPS ACRS THE ERN HALF OF THE CWFA TO LIKELY BASED ON
RADAR TRENDS. THE AXIS OF THE MID LVL SHORTWAVE TROF IS IN LINE WITH
THE BACK EDGE OF PRECIP. SO EXPECT POPS TO TAPER OFF FROM WEST TO
EAST THIS EVENING. THE EXCEPTION IS ALONG THE TN LINE...WHERE POPS
LINGER THRU THE OVERNIGHT. THE LATEST RAP 850 MB INITIALIZES THE 0C
LINE STILL BACK TO THE WEST. AND TEMPS IN THE MTNS ARE STILL IN THE
UPR 30S TO MID 40S. SO CHANGEOVER TO SNOW SHWRS HAS BEEN DELAYED.
LITTLE IF ANY ACCUMS ARE EXPECTED OVERNIGHT BEFORE SHWRS TAPER OFF
AROUND DAYBREAK TUESDAY.
AS OF 655 PM...NO SIGNIFICANT CHANGES TO THE PUBLIC FCST WITH THIS
UPDATE. TWEAKED TEMPS/DWPTS AGAIN WITH LATEST OBS. SKY/WIND/POP/WX
WERE ADJUSTED WITH LATEST GUIDANCE FOR THE 00Z TAFS. BASED ON RADAR
TRENDS...IT LOOKS LIKE THE THUNDER THREAT IS PRETTY MUCH OVER IN THE
UPPER SAVANNAH VALLEY.
AS OF 430 PM...THE POP TRENDS STILL LOOK ON TRACK. THERE ARE FEW
BREAKS IN THE CLOUDS ACRS GA AND WRN UPSTATE ON VIS SAT. CONVECTION
IS DEVELOPING WHERE THERE IS SOME INSOLATION...AND STILL MAY SEE AN
ISOLD TSTM OR TWO ACRS THE UPPER SAVANNAH VALLEY AND SRN UPSTATE
OVER THE NEXT COUPLE HOURS (LAPS CAPE IS UP TO 250 TO 600+ J/KG).
CANNOT RULE OUT SMALL HAIL/GRAUPEL WITH THE HEAVIEST
CONVECTION...GIVEN THE LOW FREEZING LEVELS...AND A FEW REPORTS IN
GA. I UPDATED THE TEMPS/DWPTS WITH THE LATEST OBS. TEMPS ARE RUNNING
COOLER THAN EXPECTED...GIVEN STUBBORN RAIN AND CLOUDS.
AS OF 210 PM EST...WATER VAPOR IMAGERY SHOWS A DIGGING UPPER LEVEL
SHORTWAVE OVER THE BASE OF THE SRN APPALACHIANS THIS
AFTERNOON...GRADUALLY ACQUIRING A MORE NEUTRAL TILT AS IT MOVES
EAST. DEEP LAYER DPVA AHEAD OF THIS WAVE IS CROSSING THE ERN HALF OF
THE FORECAST AREA THIS AFTN...WHILE ADDITIONAL SCT ACTIVITY DEVELOPS
BACK TO THE WEST UNDER THE COLD TROUGH ALOFT AND AHEAD OF THE
ASSOCIATED SFC COLD FRONT. A VERY FEW CLOUD TO CLOUD LIGHTNING
STRIKES WERE INDICATED EARLIER THIS AFTN...BUT THE CLOUD COVER HAS
KEPT LAPS SFC BASED CAPE VALUES LESS THAN 100 J/KG FOR ALL AREAS
EXCEPT THE EXTREME SRN PIEDMONT. WILL CONFINE ANY ISOLD THUNDER
MENTION GOING FORWARD TO SRN AND ERN SECTIONS THROUGH LATE AFTN.
SHEAR PROFILES REMAIN TOO WEAK FOR ANY SEVERE CONVECTION.
ANTICIPATE FROPA ACROSS THE MTNS THIS EVENING...BUT THEN THE
BOUNDARY WILL WASH OUT OVER THE PIEDMONT OR POSSIBLY GET HUNG UP
NEAR THE HIGHER TERRAIN OF THE SRN MTNS AND GRADUALLY DISSIPATE. THE
PASSING UPPER TROUGH WILL DEEPEN FURTHER TONIGHT...AND POSSIBLY CUT
OFF JUST EAST OF OUR FORECAST AREA...WITH STRONGER SFC WAVE
FORMATION LIKELY OUT OVER THE COASTAL PLAIN OVERNIGHT. THIS WILL
SLOW THE DEEP LAYER DRYING FROM THE WEST...AND LEAD TO A MORE
GRADUAL WEST TO EAST DROPOFF IN POPS. IN ADDITION...SUBFREEZING 850
MB TEMPS WILL ARRIVE ALONG THE SPINE OF THE SRN APPALACHIANS TOWARD
06Z. SCATTERED WESTERN MTNS SNOW SHOWERS OVERNIGHT COULD LEAD TO
VERY LIGHT ACCUMS IN THE TN BORDER COUNTIES...HOWEVER...THE LOW
LEVEL UPSLOPE FLOW WILL BE MORE NRLY THAN DESIRED FOR DECENT UPSLOPE
PRECIPITATION. CANNOT RULE OUT SOME LIGHT ICING GIVEN THE SHALLOW
MOISTURE PROFILES AND POSSIBLE LINGERING WARM NOSE...BUT RAIN/SNOW
IS PREFERRED BY THE CONSENSUS PROFILES.
FINALLY...WEAK DEFORMATION ZONE FORCING W OF THE COASTAL LOW...ALONG
WITH LINGERING 850 MB MOISTURE IN THE NRLY FLOW...WILL LIKELY ALLOW
CLOUDS TO PERSIST OVER THE WRN CAROLINAS THROUGH MUCH OF TUESDAY.
HOWEVER...NO FURTHER SHOWERS ARE EXPECTED THIS FAR W. TEMPERATURES
WILL BE NEAR CLIMATOLOGY...EXCEPT COOLER THAN CLIMO IN WRN NC.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY/...
AS OF 145 PM MONDAY...TUESDAY NIGHT AND WED SHOULD BE QUIET ACROSS
THE WESTERN CAROLINAS AND NE GA AS SHORT WAVE RIDGING DEVLOPS ACROSS
THE AREA. HOWEVER...THE FLOW WILL QUICKLY AMPLIFY ON THURSDAY AS A
SHARP UPPER TROUGH QUICKLY DIGS SE OUT OF CANADA WITH A LONG WAVE
TROUGH DEVELOPING OVER THE EASTERN U.S. ON THURSDAY. THE DIGGING
UPPER TROUGH WILL SPAWN A CLIPPER LOW WHICH IS FORECAST TO MOVE WELL
NORTH OF THE AREA...BUT IS ASSOCIATED COLD FRONT WILL MOVE ACROSS
THE FORECAST AREA ON THURSDAY. THE FRONT WILL BE MOISTURE STARVED SO
DESPITE THE RATHER IMPRESSIVE UPPER AIR DYNAMICS...LITTLE IN THE WAY
OF PRECIP WILL ACCOMPANY THE FRONT OUTSIDE THE MOUNTAINS EXCEPT
PERHAPS SOME SPRINKLES/FLURRIES WITH THE PASSAGE OF THE UPPER TROUGH
THU AFTERNOON. HOWEVER...THE DEVELOPING NW FLOW WILL SQEEZE OUT SOME
MAINLY UPSLOPE INDUCED SNOW SHOWERS IN THE MOUTNAINS ON THU...BUT
RIGHT NOW ACCUMULATIONS LOOK TO BE ON THE LIGHT SIDE EVEN THOUGH
FORECAST SOUNDINGS LOOK SOMEWHAT CONVECTIVE. THEREFORE...WOULD NOT
BE SURPRISED IF ADVISORY LEVEL SNOW ACCUMS RESULT BY LATE THU
ESPECIALLY IN THE NORTHERN MOUNTAINS. THE BIG STORY WILL BE THE
PLUNGING TEMPS. MAX TEMPS IN THE MOUNTAINS ON THURSDAY WILL OCCUR IN
THE EARLY MORNING THEN FALLING THROUGHOUT THE DAY AS 850 TEMPS FALL
WELL INTO THE NEGATIVE TEENS. OUTSIDE THE MOUNTAINS AS
USUAL...DOWNSLOPE FLOW WILL MITIGATE COLD ADVECTION INITIALLY BUT
WILL EVENTUALLY BE OVERWHELMED BY CAA IN THE AFTERNOON. MAX TEMPS
OUTSIDE THE MOUNTAINS LOOK TO OCCUR IN THE EARLY AFTEERNOON AND THEN
FALL OFF AS 850 TEMPS FALL INTO THE NEGATIVE LOWER TEENS BY 00Z FRI.
WINDS WILL ALSO INCREASE AND BECOME GUSTY ON THURSDAY BUT LOOK TO
REMAIN BELOW ADVISORY LEVELS AT THIS POINT. MAX TEMPS SHOULD BE NEAR
CLIMO ON WED AND THEN WELL BELOW CLIMO IN THE MOUNTAINS THU AND
ABOUT A CATEGORY BELOW EAST OF THE MOUNTAINS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 210 PM MONDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON FRIDAY
WITH A HIGHLY AMPLIFIED UPPER TROF AXIS RIGHT OVER THE CAROLINAS AND
STEEP UPPER RIDGING OVER THE WESTERN CONUS. OVER THE NEXT 24
HRS...THE TROF AXIS LIFTS TO THE NE HOWEVER WE WILL LIKELY REMAIN
UNDER BROAD UPPER TROFFING THRU MOST OF THE PERIOD. ON SAT...THE
TROF AMPLIFIES AGAIN AND BRINGS ANOTHER ROUND OF IMPRESSIVE PVA AND
COLD AIR OVER THE REGION. BY EARLY MON...THIS ENERGY LIFTS NE AND
HEIGHTS RISE AS THE UPPER PATTERN FLATTENS OUT. IT SHOULD BE NOTED
THAT THE OVERALL MODEL AGREEMENT FOR THE PERIOD LOOKS ESPECIALLY
GOOD.
AT THE SFC...SIGNIFICANT CAA WILL BE UNDERWAY BY LATE THURS/EARLY
FRI AS COLD CANADIAN HIGH PRESSURE PUSHES INTO THE REGION FROM THE
NW. OVER THE NEXT 24 HRS...A LOW IS EXPECTED TO DEVELOP OVER THE
GREAT LAKES AND DRIFT SE...YET ITS LOOKING LIKE MOST OF THE DEEPER
MOISTURE ASSOCIATED WITH THAT SYSTEM WILL REMAIN TO OUR NORTH. AS
THE LOW TRACKS EASTWARD...ANOTHER STRONG CANADIAN HIGH MOVES INTO
THE REGION ON SUNDAY BRINGING SOME OF THE COLDEST/DRIEST AIR OF THE
SEASON. THE HIGH IS EXPECTED TO REMAIN OVER THE AREA THRU NEW DAY 7
WHICH IS NEXT MONDAY. THE ONLY POPS I CARRY FOR THE PERIOD ARE SMALL
AREAS OF SLIGHT CHANCE OVER THE NORTHERN MTS LATE THURS/EARLY FRI
AND SAT. OTHERWISE...IT WILL BE DRY. MORE NOTEWORTHY WILL BE WELL
BELOW NORMAL TEMPS ON FRI AND SUN WITH EQUALLY DRY DEWPTS. THESE
TEMPS COUPLED WITH GUSTY WINDS COULD CAUSE SOME FIRE DANGER ISSUES
AND WIND CHILL CONCERNS EARLY FRIDAY AND SUNDAY...ESPECIALLY OVER
THE HIGHER ELEVATIONS.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AT KCLT...LIFR CIGS IN LIGHT SHOWERS WILL CONTINUE OVER THE NEXT
SEVERAL HOURS BEFORE THE PRECIP DRYING OUT BY AROUND 8Z WITH CIGS
LIFTING TO ABOUT 800FT RANGE. AN UPPER LOW WILL CONTINUE TO SLOWLY
MOVE EASTWARD THROUGH THE DAYBREAK...YIELDING N/NNELY FLOW AND IFR
CLOUDS. EXPECT GUSTY NNE WINDS OF 15-22KTS TO DEVELOP AND CIGS
SHOULD LIFT INTO THE MVFR LVL BY THIS MORNING AS SURFACE PRESSURE
GRADIENT TIGHTENS UP BEHIND THE DEPARTING LOW. AS DRY HIGH PRESSURE
FURTHER BUILDS IN...CIGS SHOULD RISE TO VFR LVL BY MIDDAY. GUSTY
WINDS SHOULD SUBSIDE BEYOND 22Z...BUT WILL REMAIN AROUND 7-10KT
RANGE.
ELSEWHERE...AREAS OF LIGHT SHOWERS OVER THE NC PIEDMONT AND PORTIONS
OF THE EASTERN UPSTATE SC SHOULD TAPER OFF OVER THE NEXT FEW HOURS
AS THE UPPER LOW ASSOCIATED WITH PRECIP SHIELD FURTHER MOVES OFF TO
THE EAST. AN INTRUSION OF DRY SLOT BEHIND THE DEPARTING LOW WILL
YIELD VFR CIGS ACROSS MUCH OF THE REGION OVERNIGHT EXCEPT KAVL WHERE
IFR/MVFR CLOUDS SHOULD LINGER AT LEAST THRU DAYBREAK. WINDS SHOULD
INCREASE THRU THE OVERNIGHT...BECOMING GUSTY AT TIMES BY EARLY THIS
MORNING AS PRESSURE GRADIENT TIGHTENS UP BETWEEN THE DEPARTING LOW
AND HIGH PRESSURE TO THE NW. EXPECT VFR CONDITIONS TO PREVAIL TODAY
UNDER THE INFLUENCE OF BUILDING HIGH PRESSURE. GUSTY WINDS OF
10-20KTS SHOULD DECREASE TO AROUND 5-10KT BY THE AFTERNOON.
OUTLOOK...DRYING CONDITIONS ARE EXPECTED LATE TUE THROUGH WED. A
COLD FRONT WILL CROSS THE REGION FROM THE NW ON THU...BUT WITH
LIMITED MOISTURE. BREEZY TO WINDY CONDITIONS ARE EXPECTED BEHIND THE
FRONT THU THROUGH FRI...WITH COLDER TEMPERATURES.
CONFIDENCE TABLE...
06-12Z 12-18Z 18-24Z 00-06Z
KCLT HIGH 80% MED 79% HIGH 97% HIGH 100%
KGSP MED 65% HIGH 92% HIGH 100% HIGH 100%
KAVL LOW 57% MED 73% HIGH 100% HIGH 100%
KHKY LOW 25% MED 65% HIGH 100% HIGH 100%
KGMU MED 63% HIGH 85% HIGH 100% HIGH 100%
KAND LOW 58% MED 74% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...CSH
NEAR TERM...ARK/HG
SHORT TERM...LG
LONG TERM...JPT
AVIATION...JOH
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1056 PM CST MON FEB 9 2015
.UPDATE...
ISSUED AT 848 PM CST MON FEB 9 2015
HAVE UPDATED THE FORECAST TONIGHT TO ADD A DENSE FOG ADVISORY FOR
SOUTH CENTRAL SOUTH DAKOTA. CURRENT WEB CAMS IN KIMBALL LOOK
FAIRLY DAUNTING...AND CHAMBERLAIN WEB CAMS SHOW STRATUS HANGING
JUST ABOVE THE GROUND. HRRR AND RAP BOTH SHOW DENSE FOG DEVELOPING ACROSS
CENTRAL SOUTH DAKOTA THIS EVENING. QUESTIONS REMAIN AS TO HOW LONG
THE DENSE FOG WILL STICK AROUND. STRONG AND DEEP WARM AIR
ADVECTION ACROSS SOUTH CENTRAL SOUTH DAKOTA MAY ALLOW FOR STEADY
IF NOT RISING TEMPERATURES TONIGHT ACROSS CENTRAL SOUTH DAKOTA.
WITH STRONG WARM AIR ADVECTION...EXPECT SOME SHOWERS TO DEVELOP
TOWARDS THE 06Z TIME FRAME ACROSS CENTRAL SOUTH DAKOTA THROUGH THE
OVERNIGHT. THE SHOWERS MAY NOT BE SO PROBLEMATIC ACROSS CENTRAL
SOUTH DAKOTA AS LONG AS TEMPERATURES AT THE SURFACE REMAIN ABOVE
FREEZING...BUT SHOWERS ARE EXPECTED TO SHIFT EAST INTO THE COLDER
AIR CREATING A SET UP FOR FREEZING RAIN AND SLEET. FOR NOW...THE
AREAL COVERAGE LOOKS GOOD FOR FREEZING RAIN...BUT LOWERED ICING
POTENTIAL ACROSS THE WEST WITH WARMER TEMPERATURES.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 335 PM CST MON FEB 9 2015
MAIN FOCUS IN THE SHORT TERM WILL BE A POTENT UPPER LEVEL TROUGH
TRACKING EAST ACROSS THE NORTHERN PLAINS. THE LOW STRATUS WILL
LINGER THIS EVENING AS LIGHT SOUTHEAST WINDS INCREASE AHEAD OF THE
WAVE. LIGHT PRECIPITATION WILL BEGIN SPREADING INTO THE WESTERN
FORECAST AREA LATER THIS EVENING AS MID AND HIGH CLOUDS ARRIVE WITH
THE WAVE. PRECIPITATION WILL GRADUALLY SPREAD EAST
OVERNIGHT...REACHING THE INTERSTATE 29 CORRIDOR IN THE EARLY MORNING
HOURS AND OUR FAR EASTERN FORECAST AREA LATE TONIGHT. THE LOW CLOUDS
WILL PERSIST...BUT THE MAIN CONCERN WILL BE THE RATHER SIGNIFICANT
DRY LEVELS FROM 750 TO 850 MB BETWEEN THE CLOUD LAYERS. WE DO SEE
SOME WEAK LIFT IN BOTH LAYERS...WHICH COULD SPELL MORE FREEZING
DRIZZLE TYPE PRECIPITATION...BUT ALSO THINK THAT SOME IMPACT FROM
THE MID CLOUDS WILL POINT TO AT LEAST SOME POTENTIAL FOR LIGHT
MEASURABLE PRECIPITATION. WITH THE MODELS TAKING THE BEST FORCING
AND SUPPORT JUST TO OUR NORTH...OUR BEST POTENTIAL WILL BE NORTH OF
INTERSTATE 90. PRECIPITATION TAPERS OFF TUESDAY MORNING FROM WEST TO
EAST AND SHOULD BE LARGELY DONE BY MIDDAY.
FORECAST SOUNDINGS SHOW THAT THE MAIN PRECIPITATION WILL BE RAIN.
WITH THE VAST MAJORITY OF THE FORECAST AREA EXPECTED TO BE AT OR
BELOW FREEZING...FREEZING RAIN SHOULD BE THE MAIN TYPE. A LITTLE
ELEVATED INSTABILITY DOES TRACK ACROSS OUR NORTHERN HALF...WHICH MAY
ALLOW MORE OF A SHOWERY ELEMENT LATE TONIGHT. SLEET WILL ALSO BE A
POSSIBILITY MAINLY EAST CENTRAL SD INTO SOUTHWEST MINNESOTA. THERE
REMAINS SOME UNCERTAINTY ON THE IMPACT OF SOME LIGHT ICING WITH THE
FREEZING RAIN BUT IT DOES NOT TAKE MUCH ICE TO CREATE SLIPPERY
SURFACES AND UNTREATED ROADWAYS. DECIDED TO GO WITH A FREEZING RAIN
ADVISORY LATE TONIGHT THROUGH TUESDAY MORNING FOR THE HIGHWAY 14
CORRIDOR INTO THE SIOUX FALLS AREA WHERE THE BEST POTENTIAL FOR SOME
LIGHT ICE ACCUMULATION IS POSSIBLE - YET EVEN HERE AM ONLY EXPECTING
LESS THAN 0.05 INCHES. DEBATED LEAVING THE FSD AREA OUT OF THE
ADVISORY...BUT GIVEN THE TIMING OF THE ICE POTENTIAL WILL BE AROUND
THE MORNING COMMUTE FELT THAT THE ADVISORY WOULD GIVE THE PROPER
HEADS UP FOR A POSSIBLE SLICK COMMUTE. WE WILL HAVE TO SEE IF AND
HOW THE CONVECTIVE ELEMENT PLAYS OUT...WHICH MAY REQUIRE ADJUSTING
THE ADVISORY ZONES.
CLOUDS START CLEARING IN SOUTH CENTRAL SD IN THE AFTERNOON BUT
LINGER THROUGH THE DAY ELSEWHERE. BUT THE BREEZY SOUTHERLY WINDS
TURNING NORTHWESTERLY BEHIND THE FRONT SHOULD ALLOW SOME DECENT
WARMING REGARDLESS. HIGHS WILL BE MILDER IN THE UPPER 30S TO MID
50S...SO ANY SLICK SPOTS ON ROADWAYS SHOULD MELT IN THE AFTERNOON.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 335 PM CST MON FEB 9 2015
A STRONG COLD FRONT WILL BLAST THROUGH THE AREA ON TUESDAY NIGHT.
WITH THE COLD AIR ADVECTION AND A STEEPENING GRADIENT IT WILL BECOME
INCREASINGLY WINDY DURING THE NIGHT. A SECONDARY SHORTWAVE WILL DROP
SOUTHWARD ON A NORTHWESTERLY UPPER LEVEL FLOW OVERNIGHT...AND WITH
A SATURATED DENDRITIC LAYER KEPT WITH SCATTERED FLURRIES IN PORTIONS
OF OUR NORTH AND EAST LATER IN THE NIGHT. WITH THE COLD AIR
ADVECTION LOWS WILLS DROP DOWN INTO THE MID TEENS TO LOWER 20S.
HIGH PRESSURE BUILDS INTO THE NORTHERN PLAINS ON WEDNESDAY AND
WEDNESDAY NIGHT. IT WILL REMAIN BREEZY THROUGH THE DAY HOWEVER WITH
GOOD MIXING...AND WINDS WILL ONLY SLOWLY FALL OFF ON WEDNESDAY
NIGHT. WITH THERMAL PROFILES CONTINUING TO COOL...HIGHS ON WEDNESDAY
WILL ONLY BE IN THE TEENS NORTHEAST TO NEAR 30 ALONG THE MO RIVER
CORRIDOR...DROPPING OFF TO JUST EITHER SIDE OF ZERO ON WEDNESDAY
NIGHT.
THE RIDGE AXIS SLIDES ACROSS THE REGION ON THURSDAY...WITH THE BRUNT
OF THE COLDER AIR SITTING OVER THE AREA HIGHS WILL ONLY MAKE IT INTO
THE TEENS TO MID 20S. AS THE HIGH MOVES OFF TO THE EAST...A
SOUTHERLY FLOW RETURNS TO THE REGION ON THURSDAY NIGHT...AND
OVERNIGHT LOWS WILL BE VERY SIMILAR TO THURSDAYS HIGHS...REMAINING
NEARLY STEADY IN THE TEENS AND LOWER 20S. MODELS IN DECENT AGREEMENT
ON A COLD FRONTAL PASSAGE ON FRIDAY MORNING...BUT WITH GOOD MIXING
BEHIND THE FRONT IT WILL REMAIN MILD WITH HIGHS ON FRIDAY BACK ABOVE
NORMAL...IN THE UPPER 20S TO LOWER 40S.
THE ROLLERCOASTER RIDE IN TEMPERATURES CONTINUES INTO THE EXTENDED
WITH VARIOUS WAVES PASSING TO OUR EAST IN A NORTHWESTERLY UPPER
LEVEL FLOW. AFTER A COOL DOWN ON SATURDAY...TEMPERATURES LOOK TO
REBOUND FOR THE BEGINNING OF NEXT WEEK. IT APPEARS TO BE DRY THROUGH
MOST OF THE EXTENDED...BEFORE INDICATIONS OF POSSIBLE PRECIPITATION
ON MONDAY AS ANOTHER SHORTWAVE SLIDES INTO THE REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1051 PM CST MON FEB 9 2015
LOW STRATUS AND AREAS OF FOG TO CONTINUE THROUGH THE FORECAST
PERIOD. THINK THE FOG WILL REMAIN CONTAINED MAINLY WEST OF THE
JAMES...SO HAVE RAISED VISIBILITIES IIN NEW TAFS. WAVE MOVING
THROUGH THE AREA WILL PRODUCE LIGHT FREEZING RAIN TO THE NORTH
ALONG HIGHWAY 14...WITH LESSER AMOUNTS TO THE SOUTH. REMOVED
MENTION OF FREEZING RAIN AT KHON BECAUSE IT MAY BE TOO WARM. WAS
CLOSE TO REMOVING MENTION OF FREEZING RAIN AT KFSD AS WELL...AND
NEXT SHIFT MAY BEFORE ISSUING THE TAFS. GUSTY NORTHWEST WINDS WILL
INCREASE FROM NORTHWEST TO SOUTHEAST TOMORROW IMPROVING CEILINGS
INTO THE MVFR RANGE. &&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...DENSE FOG ADVISORY UNTIL 9 AM CST TUESDAY FOR SDZ050-052-057>059-
063-064-068.
FREEZING RAIN ADVISORY UNTIL NOON CST TUESDAY FOR SDZ038>040-
052>056-061-062.
MN...FREEZING RAIN ADVISORY UNTIL NOON CST TUESDAY FOR MNZ071-072-097-
098.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...
SHORT TERM...
LONG TERM...JM
AVIATION...
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
442 AM EST TUE FEB 10 2015
.SYNOPSIS...
LOW PRESSURE OVER THE SOUTH CAROLINAS WILL DRIFT EAST AND
OFFSHORE TODAY. HIGH PRESSURE WILL BUILD IN ON WEDNESDAY. AN
ARCTIC COLD FRONT MOVES THROUGH ON THURSDAY MORNING.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 400 AM EST TUESDAY...
MAIN 500 MB SHORT WAVE WAS TRACKING ACROSS NORTH CAROLINA WITH THE
ASSOCIATED SURFACE LOW OFF THE COAST OF SOUTH CAROLINA. MODELS HAVE
THE 500 MB LOW CUTTING OFF THIS MORNING THEN MOVING SLOWLY EAST. AT
THE SURFACE...THE LARGEST PRESSURE FALLS WERE OFF THE CAROLINA
COAST. BY LATE THIS MORNING THE LOW WILL BE WELL OFFSHORE.
WESTERN EDGE OF THE PRECIPITATION EXTENDED FROM LEXINGTON TO
HILLSVILLE AT 400 AM. THE PRECIPITATION WILL GRADUALLY END FROM WEST
TO EAST TODAY. LOCAL WRF AND HRRR MODELS SHOWED BACK EDGE EXITING
THE FAR EASTERN COUNTY WARNING AREA AROUND 1PM. THERE MAY BE SOME
CLEARING LATE IN THE DAY IN THE SOUTHERN FOOTHILLS BUT OVERALL CLOUD
COVER AND PRECIPITATION WILL HOLD TEMPERATURES DOWN. HAVE LEANED
TOWARD COOLER LAV GUIDANCE FOR MAXIMUM TEMPERATURES TODAY.
TEMPERATURES AND DEW POINTS WERE DROPPING THIS MORNING FROM BOTH THE
NORTH AND THE WEST. MESONET DATA SHOWED SOME TEMPERATURES AROUND
FREEZING ALONG THE BLUE RIDGE IN ROCKBRIDGE COUNTY...IN TAZEWELL
COUNTY AND IN THE HIGHER ELEVATIONS OF WATAUGA COUNTY. THESE HIGHER
ELEVATIONS WILL BE IN THE CLOUDS THIS MORNING SO SOME FREEZING FOG
IS POSSIBLE. VERY LIGHT ICING IN POSSIBLE ALONG THE BLUE RIDGE
BETWEEN ROCKBRIDGE AND AMHERST COUNTIES ON THE EXTREME WESTERN EDGE
OF THE PRECIPITATION SHIELD.
WINDS BECOME LIGHT AND VARIABLE OVER THE MOUNTAINS TONIGHT AS A
RIDGE OF HIGH PRESSURE MOVES INTO THE AREA. EXPECTING SOME GUSTY
WINDS IN THE EAST THIS MORNING THEN WINDS WILL DIMINISH THIS
AFTERNOON AND OVERNIGHT. STAYED CLOSE TO BIAS CORRECTED GUIDANCE FOR
OVERNIGHT LOWS.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
AS OF 345 AM EST TUESDAY...
WILL START WEDNESDAY OFF WITH ZONAL WEST TO EAST WIND FLOW BECOMING
INCREASINGLY ESTABLISHED FOR THE CENTRAL APPALACHIANS...AS LOW
PRESSURE OFF THE ATLANTIC COAST MOVES AWAY...AND A DEEP UPPER LEVEL
TROUGH BEGINS TO DIG ACROSS THE GREAT LAKES FROM NORTHERN CANADA.
HIGH PRESSURE WILL ALREADY BE ESTABLISHED IN THE LOW LEVELS...MAKING
FOR MOSTLY CLEAR SKIES. ABUNDANT SUNSHINE AND DOWNSLOPE WINDFLOW
WILL COMBINE TO PUSH AFTERNOON TEMPERATURES INTO THE UPPER 40S TO
MID 50S AREAWIDE. CLOUD COVER WILL INCREASE DURING THE EVENING
HOWEVER AS THE UPPER LEVEL TROUGH CONTINUES ITS APPROACH...WITH AN
ASSOCIATED ARCTIC COLD FRONT MAKING ITS WAY TOWARD THE APPALACHIAN
CHAIN THROUGH THE NIGHT...TRIGGERING LIGHT SNOW SHOWERS ACROSS THE
WESTERN RIDGES TOWARD DAWN THURSDAY.
THE ARCTIC COLD FRONT WILL BEGIN ITS PASSAGE ACROSS OUR AREA
THURSDAY MORNING...ENTERING SOUTHEAST WEST VIRGINIA AND THE MOUNTAIN
EMPIRE AROUND SUNRISE...AND REACHING THE COASTAL PLAIN BY MID
AFTERNOON. HIGH TEMPERATURES FOR THURSDAY WILL OCCUR DURING THE
MORNING JUST AHEAD OF FRONTAL PASSAGE. THE AIR BEHIND THE FRONT IS
COLD ENOUGH THAT IT WILL OVERCOME NORMAL DAYTIME HEATING...AND
THEREFORE WE WILL SEE TEMPERATURES STEADILY DROP THROUGH THE
AFTERNOON. HIGHS WILL RANGE FROM AROUND THE FREEZING MARK WEST OF
INTERSTATE 77...TO THE MID AND UPPER 40S ACROSS THE SOUTHSIDE.
SNOW SHOWERS CAN BE EXPECTED ALONG THE WESTERN RIDGES DURING THE
AFTERNOON...HOWEVER WINDS WILL NOT TRULY SHIFT NORTHWESTERLY UNTIL
EARLY EVENING ACROSS THE MOUNTAINS...WHEN THE BASE OF THE UPPER
TROUGH PASSES OVERHEAD. THE NORTHWESTERLY WIND SHIFT WILL BE FROM
THE PERFECT DIRECTION TO DRAW MOISTURE FROM LAKE MICHIGAN THURSDAY
EVENING INTO EARLY FRIDAY MORNING...WHEN THE HIGHEST SNOWFALL
ACCUMULATIONS ARE EXPECTED. 850MB TEMPERATURES FALLING INTO THE -16C
TO -20C RANGE ALONG THE WESTERN RIDGES WILL SUPPORT SNOW TO LIQUID
RATIOS IN THE 20:1 TO 25:1 RANGE. IN ADDITION...STRONG WINDS AND
UNIDIRECTIONAL FLOW MAY SUPPORT SNOW STREAMERS...WHERE NARROW BANDS
OF LOCALIZED HEAVY SNOW MAY OCCUR...POSSIBLY REACHING INTO THE NEW
RIVER VALLEY. WIND GUSTS OF 45 TO 50 MPH WILL BE COMMON ALONG THE
HIGHER RIDGES DURING THE EVENING...WELL INTO WIND ADVISORY CRITERIA.
BY SUNRISE FRIDAY...TEMPERATURES WILL HAVE FALLEN INTO THE POSITIVE
SINGLE DIGITS ACROSS THE MOUNTAINS...AND INTO THE LOW TO MID TEENS
ACROSS THE PIEDMONT. THESE COLD TEMPERATURES...WHEN FACTORING IN THE
STRONG WINDS...WILL CAUSE WIND CHILLS TO RANGE FROM NEAR ZERO ACROSS
THE SOUTHSIDE...TO THE NEGATIVE TEENS WEST OF THE BLUE RIDGE...
POSSIBLY AS LOW AS -30F IN A FEW SPOTS ALONG THE INTERSTATE 64
CORRIDOR. WIND SPEEDS WILL DECREASE HEADING INTO FRIDAY AFTERNOON...
ALLOWING WIND CHILLS TO RISE ABOVE ZERO MOST LOCATIONS. WINDS WILL
SHIFT MORE WESTERLY LATE IN THE DAY...WITH CLOUD COVER DECREASING...
WHICH WILL HELP AFTERNOON TEMPERATURES REBOUND INTO THE LOW 20S WEST
AND THE LOW 30S EAST. FRIDAY NIGHT TEMPERATURES WILL NOT BE AS
CHILLY...HOLDING IN THE TEENS MOST LOCATIONS.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 300 PM EST MONDAY...
BOTH THE GFS AND ECMWF KEEP NORTHWEST FLOW WITH A TROUGH/LOW NEAR
JAMES BAY AND RIDGING OVER THE WESTERN U.S. THROUGH SUNDAY.
A SHORTWAVE TROUGH IS FORECASTED TO ROTATE AROUND THE LONGWAVE
PATTERN THROUGH THE GREAT LAKES REGION AND INTO NEW ENGLAND.
THE SOUTHERN EXTENT OF THE ENERGY AND MOISTURE WITH THIS FEATURE IS
SLIGHTLY DIFFERENT DEPENDING ON MODEL CHOICE. STILL LEANING TOWARDS
THE DRIER AND LESS AMPLIFIED SOLUTION WITH RICHER MOISTURE NORTH OF
THE AREA. PLACED ISOLATED TO SCATTERED POPS IN THE WEST WITH THE
BEST CHANCES IN THE NORTHWEST FOR SATURDAY INTO SATURDAY NIGHT.
WINDS INCREASE SATURDAY INTO SATURDAY NIGHT WITH HEALTHY 4 TO 8 MB 6
HOUR PRESSURE RISES. HIGHS ON SATURDAY WILL VARY FROM THE LOWER 20S
IN THE NORTHWEST MOUNTAINS TO THE LOWER 40S IN THE PIEDMONTS.
THE COMBINATION OF WINDS AND TEMPERATURES WILL PRODUCE WIND CHILLS
BELOW ZERO AT THE HIGHER ELEVATIONS SATURDAY NIGHT INTO SUNDAY
MORNING. ACTUAL LOW TEMPERATURES SATURDAY WILL DROP INTO SINGLE
DIGITS TO MID TEENS. HIGH PRESSURE WILL SLOWLY SLIDE EAST SUNDAY
INTO SUNDAY NIGHT. HIGHS SUNDAY WILL VARY FRO THE MID TEENS IN THE
NORTHWEST TO LOWER 30S IN THE SOUTHEAST. ANOTHER COLD SUNDAY NIGHT
WITH LOW TEMPERATURES GENERALLY FROM THE SINGLE DIGITS AND TEENS.
THE HIGH CENTER MOVES SOUTHEAST ON MONDAY AND UPPER FLOW FLATTENS.
THE HIGH CENTER PUSHES OFF INTO THE ATLANTIC OCEAN MONDAY NIGHT INTO
TUESDAY. A COLD FRONT APPROACHES FROM THE WEST ON TUESDAY.
&&
.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
AS OF 1115 PM EST MONDAY...
RATHER COMPLEX SCENARIO TONIGHT WITH WEAK LOW PRESSURE OVER THE
CAROLINAS AND A RESIDUAL FRONT NOW TO THE SOUTH OF THE REGION.
RAINFALL REMAINS QUITE PATCHY IN ALL AREAS EXCEPT OVER THE SE
WHERE CORRIDOR OF LIFT TO THE NW OF THE FRONT AND WEAK SURFACE
LOW HAS AN AXIS OF LIGHT/MODERATE RAINFALL PERSISTING AROUND KDAN
IN THE DEVELOPING DEFORMATION ZONE. OVERALL DEEPER MOISTURE WILL
BE SLOW TO EXIT GIVEN GRADUAL CUTTING OFF NATURE TO THE 5H SYSTEM
ALOFT WITH MAIN CHANGES WITH LOW LEVEL ADVECTION OF MOISTURE AND
COLDER AIR THROUGH MORNING. THUS STILL EXPECTING THE DEVELOPMENT
OF IFR MOST SITES OVERNIGHT WITH NE FLOW BLUE RIDGE EAST AND A
MORE NW UPSLOPE COMPONENT OUT WEST. OTHERWISE APPEARS MOST CLOUD
BASES TO DROP INTO IFR SHORTLY AFTER MIDNIGHT...WITH MVFR TO IFR
VSBYS POSSIBLE AT KDAN...AND IN SPOTS OVER THE WEST IN FOG
INCLUDING LIGHT SNOW/SLEET OR PATCHY FREEZING RAIN LATE.
SURFACE LOW SHIFTS OFFSHORE EARLY TUESDAY AND DEEPENS AS THE UPPER
SYSTEM CATCHES UP WHICH HELPS TO HOLD THE DEFORMATION ZONE OVER SE
SECTIONS INTO AT LEAST TUESDAY MORNING. BUFKIT SOUNDINGS HAVE
CONTINUED TO SLOW DOWN THE EXODUS OF DEEPER MOISTURE FROM
KLYH/KDAN SO LINGERING SOME LIGHT RAIN IN BOTH LOCATIONS INTO
TUESDAY MORNING. APPEARS WILL STAY LIQUID GIVEN RATHER WARM
BOUNDARY LAYER AND TEMPS ALOFT REMAINING JUST ABOVE FREEZING BUT
SOMETHING TO WATCH AROUND KLYH WHERE COULD BE A BRIEF PERIOD OF
-SN/PL NEAR THE END OF THE EVENT. OTHERWISE LOOKING FOR GRADUAL
DRYING FROM THE NORTH TUESDAY AFTERNOON BUT WILL BE SLOW UNDER THE
INVERSION SO KEEPING MVFR CIGS MOST SPOTS UNTIL EARLY OR MID
AFTERNOON BEFORE LIFTING INTO VFR LEVELS INTO TUESDAY EVENING
OUTSIDE OF KBLF WHERE FORECAST SOUNDINGS SHOW MVFR CIGS
PERSISTING.
EXTENDED AVIATION DISCUSSION...
HIGH PRESSURE AND COLDER AIR IS EXPECTED TO BUILD IN BEHIND THE
COLD FRONT WITH A RETURN TO VFR FOR WEDNESDAY. UPSLOPE SNOW
SHOWERS ARE EXPECTED IN THE MOUNTAINS ON WEDNESDAY NIGHT AND
THURSDAY ALONG WITH A SHARP DROP IN TEMPERATURES THURSDAY AND
THURSDAY NIGHT BEHIND AN ARCTIC COLD FRONT. WIND GUSTS BEHIND THE
FRONT ON THURSDAY NIGHT MAY REACH 40-50 KNOTS IN THE HIGHER
ELEVATIONS. HIGH PRESSURE BUILDS IN ALLOWING FOR DIMINISHING WINDS
ON FRIDAY WITH SOME LINGERING MVFR CIGS POSSIBLE OVER THE
SOUTHEAST WEST VA LOCATIONS. ANOTHER FAST MOVING ARCTIC FRONT
ARRIVES SATURDAY WITH A RESUMPTION OF UPSLOPE SNOW SHOWERS
INCLUDING MVFR CIGS/VSBYS ALONG WITH INCREASING NORTHWEST WINDS
THAT COULD AGAIN GUST TO 50 KNOTS BY LATE IN THE DAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...NF
LONG TERM...KK
AVIATION...AMS/JH/MBS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1116 PM CST MON FEB 9 2015
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY)
ISSUED AT 245 PM CST MON FEB 9 2015
MODELS REMAIN IN GOOD AGREEMENT WITH SLIDING AN UPPER LEVEL
SHORTWAVE TROUGH ACROSS THE PLAINS AND THEN OVER NORTHERN PARTS OF
THE REGION TUE. CONSENSUS HAS SHIFTED TO A MORE NORTHERN TRACK FOR
THIS SYSTEM...ALA WHAT THE EC WAS SUGGESTING YESTERDAY. WILL FOLLOW
THIS FOR PCPN CHANCES. IN ADDITION...TRENDS ALSO HAVE MOVED TO A
SLIGHTLY SLOWER SOLUTION...WHICH LOOKS REASONABLE.
SWATH OF OF 925-700 MB WARMING LEADS THE SHORTWAVE...WITH SOME OF
THIS LIFT LIKELY GOING INTO DEEPENING THE SATURATION. GOOD RISES ON
THE 280-295 K SURFACES TOO...GREATER ACROSS CENTRAL MN/NORTHERN WI
TUE AFTERNOON-EVENING. THE DEEPER...STRONG QG CONVERGENCE IS LOCATED
IN THE SAME AREA-TIME FRAME.
NORTH-SOUTH RUNNING TIME/HEIGHT X-SECTIONS AND BUFKIT SOUNDINGS
SUGGEST THE SATURATED LAYER WOULD BE COLD ENOUGH TO SUPPORT ICE BY
THE TIME PCPN BECOMES LIKELY. THE SATURATION LOOKS LIKE IT WILL COME
FROM THE TOP DOWN. GFS/NAM BUFKIT SOUNDINGS HINT THAT THERE COULD BE
NEAR SFC MOISTURE TO CONTEND WITH...BUT DON/T THINK THIS IS A
CERTAINTY. AND IF SO...THAT CLOUD LAYER LOOKS TO SHALLOW TO SUPPORT
DRIZZLE PRODUCTION...ESPECIALLY INITIALLY. STILL SEE SOME THREAT FOR
FREEZING DRIZZLE ACROSS THE FAR SOUTH AND WILL CONTINUE A MENTION
FOR PARTS OF NORTHEAST IA/SOUTHWEST WI.
FOR SNOW TOTALS...HIGHEST AMOUNTS CONTINUE TO HOLD TO THE
NORTH...WITH RATIOS ON THE LOWER SIDE. 2-3 INCHES LOOK REASONABLE
NORTH OF HIGHWAY 29 IN NORTH-CENTRAL WI...DECREASING QUICKLY AS YOU
MOVE SOUTH TOWARD I-90.
WINDS WILL PICK UP BY WEDNESDAY IN THE WAKE OF THE DEPARTING LOW
PRESSURE SYSTEM. TIGHT PRESSURE GRADIENT SHOULD RESULT IN SUSTAINED
WIND OF 15 TO 25 MPH...WITH GUSTS UPWARDS OF 35 MPH IN THE WIND
PRONE AREAS. COULD HAVE SOME BLOWING SNOW ISSUES FOR THOSE LOCATIONS
WHERE THE SNOW FALLS TUE - MOSTLY NORTH OF I-90. CURRENT SNOWPACK IS
OLDER AND WILL BE HARD TO MOVE.
WITH WINDS STAYING STIFF INTO THU MORNING...AND A PUSH OF COLD AIR
MOVING DOWN FROM CANADA...WIND CHILL ARE EXPECTED TO FALL INTO THE
-15 TO -25 RANGE. MIGHT NEED A WIND CHILL ADVISORY THU MORNING FOR A
PORTION OF THE AREA.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 245 PM CST MON FEB 9 2015
GFS/ECMWF IN GOOD AGREEMENT WITH DROPPING A VIGOROUS UPPER LEVEL
SHORTWAVE TROUGH OVER THE GREAT LAKES FRI AFTERNOON-SAT. CURRENT
TRACK WOULD KEEP THE BULK OF THE SYSTEM/S FORCING EAST OF THE LOCAL
FORECAST AREA. WEST-EAST RUNNING X-SECTIONS AND SOUNDINGS POINT TO A
SHALLOWING IN THE CLOUD LAYER THE FARTHER WEST YOU MOVE FROM THE
HEART OF THE SHORTWAVE...BUT THE SATURATED LAYER IS STILL COLD
ENOUGH FOR ICE IN THE CLOUD. DON/T THINK FREEZING DRIZZLE WILL BE
CONCERN. BUT...GIVEN THE PROXIMITY OF THE SYSTEM AND SOME LOW LEVEL
WARM AIR ADVECTION...CAN/T RULE OUT A CHANCE FOR LIGHT SNOW EAST OF
THE MISSISSIPPI RIVER. AMOUNTS LOOK MINIMAL AT THIS TIME. EXPECT
SOME SHIFT IN THE SYSTEM AS WE APPROACH THE WEEKEND.
WHILE THE SHORTWAVE ISN/T EXPECTED TO BRING MUCH SNOW TO THE AREA AT
THIS TIME...IT DOES LOOK LIKE IT WILL PACK A PUNCH WHEN IT COMES TO
WINDS. INCREASING PRESSURE GRADIENT FOR FRI NIGHT/SAT MORNING WITH A
STRONG PRESSURE COUPLET. PRESSURE GRADIENT MAGNITUDES VIA THE GFS
AND ECMWF SUGGEST GUSTS FROM 40 TO 50 KTS EAST OF THE MISSISSIPPI
RIVER...AS DOES MOMENTUM TRANSFER TO THE SFC IN BUFKIT SOUNDINGS.
THIS DOESN/T TAKE INTO ACCOUNT THE HIGHER WINDS THAT USUALLY OCCUR
IN THE OPEN/UNSHELTERED AREAS OF SOUTHEAST MN/NORTHEAST IA. STRONG
WINDS WOULD LIKELY OCCUR FOR THE BETTER PART OF SAT...WITH
IMPROVEMENT BY LATE AFTERNOON AS HIGH PRESSURE STARTS TO PUSH IN
FROM THE WEST.
AS IT STANDS RIGHT NOW...HIGH WIND WATCHES COULD BE NEEDED...WITH
UPGRADES TO ADVISORIES OR WARNINGS FOR FRI NIGHT-SATURDAY. BLOWING
SNOW WOULD LIKELY ALSO BECOME AN ISSUE WHERE LIGHT SNOW HAS
RECENTLY FALLEN. TRAVEL COULD/WOULD BE IMPACTED.
ANOTHER SHOT OF ARCTIC AIR FOR THE WEEKEND WITH 850 MB TEMPS AS COLD
AS -28 C SAT. HIGHS COULD STRUGGLE TO REACH THE TEENS. ADD IN THE
STRONG WINDS...AND WIND CHILLS COULD BECOME A CONCERN FRI NIGHT/SAT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1116 PM CST MON FEB 9 2015
SHORT WAVE TROUGH CURRENTLY OVER EASTERN WYOMING WILL CONTINUE TO
MOVE NORTHEAST AND ACROSS THE REGION TUESDAY. THE 10.00Z NAM SHOWS
THAT THIS WAVE SHOULD BE ABLE TO PRODUCE A SHORT PERIOD OF STRONG
PV ADVECTION IN THE 500-300 MB LAYER TUESDAY AFTERNOON. AS A WEAK
SURFACE LOW TRACKS ACROSS CENTRAL MINNESOTA...A WARM FRONT IS
EXPECTED TO COME ACROSS WITH THE SHORT WAVE TROUGH WITH 5 TO 6
UBAR/S OF UP GLIDE ON THE 285K ISENTROPIC SURFACE ALONG AND BEHIND
THE WARM FRONT. THE FRONTOGENESIS LOOKS TO BE VERY WEAK AND
DISORGANIZED WITH THIS SYSTEM. THE RAP FOR SEVERAL RUNS HAS BEEN
SUGGESTING THAT SOME WEAK INSTABILITY COULD COME IN WITH THIS
SYSTEM WITH UP TO 100 J/KG OF MU CAPE IN THE WARM SECTOR AND TRIES
TO SHOW THE SNOW GOING CONVECTIVE WITH RATES OF 1 TO 2 INCHES PER
HOUR. HOWEVER...THE HRRR KEEPS THESE CONDITIONS FARTHER
NORTH...CLOSER TO THE SURFACE LOW AND SHORT WAVE TROUGH WHILE THE
NAM DOES NOT SHOW THIS AT ALL. FOR NOW...FEEL THE RAP IS A BIT OF
AN OUTLIER AND WILL NOT INDICATE ANY CONVECTIVE SNOWS. THERE
SHOULD STILL BE ENOUGH FORCING FOR A GOOD BURST OF SNOW ALONG AND
BEHIND THE WARM FRONT WITH BOTH TAF SITES GOING DOWN TO IFR FOR A
TWO TO THREE HOUR PERIOD BEFORE LIKELY COMING BACK UP TO MVFR. HOW
LONG THE LIGHT SNOW THEN PERSISTS IS SOMEWHAT QUESTIONABLE. WITH
THE BEST FORCING OFF TO THE EAST WITH THE SHORT WAVE
TROUGH...THERE IS JUST SOME WEAK ISENTROPIC UP GLIDE IN THE WARM
SECTOR. IF THIS IS ENOUGH TO PRODUCE SOME PRECIPITATION...THE NAM
WOULD SUGGEST A LOSS OF ICE FOR A CHANCE OF FREEZING DRIZZLE
TUESDAY EVENING. FOR NOW...HAVE NOT INCLUDED THIS AS CONFIDENCE IS
NOT HIGH ENOUGH THAT THERE WILL BE ANY PRECIPITATION AT THAT TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION...04
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1011 AM EST TUE FEB 10 2015
.UPDATE...
THE SYNOPSIS AND NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 1011 AM EST TUE FEB 10 2015
HIGH PRESSURE WILL BRING DRY WEATHER TO THE AREA TODAY AND HIGHS
NEAR NORMAL TODAY AND SLIGHT ABOVE NORMAL WEDNESDAY. HOWEVER AN
ARCTIC FRONT WILL MOVE THROUGH THE AREA WEDNESDAY AFTERNOON AND
EVENING AND BRING SOME CHANCES FOR MIXED PRECIPITATION AND THEN
SNOW WEDNESDAY NIGHT AND THURSDAY ALONG WITH MUCH COLDER AIR.
UPPER TROUGHING WILL KEEP COLDER THAN NORMAL TEMPERATURES IN PLACE
THROUGH AT LEAST THE WEEKEND.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1011 AM EST TUE FEB 10 2015
WESTERN HALF OF THE FORECAST AREA ENJOYING MOSTLY SUNNY SKIES THIS
MORNING WHILE EASTERN COUNTIES REMAIN UNDER STRATUS. CHILLY START
WITH TEMPS RANGING FROM THE HIGH TEENS INTO THE 20S AT 15Z.
FEW CHANGES NECESSARY FOR MORNING UPDATE FOCUSED ON CLOUD COVER
AND IMPACTS TO AFTERNOON HIGHS. STRATUS DECK HAS EXPANDED WESTWARD
ACROSS EASTERN COUNTIES SO FAR THIS MORNING. RAP SHOWING LOW LEVEL
FLOW WILL REMAIN EASTERLY AT LEAST FOR THE NEXT FEW HOURS BEFORE
GRADUALLY VEERING TO THE SOUTHEAST BY AFTERNOON. THE EASTERLY FLOW
SHOULD ENABLE SOME ADDITIONAL WESTWARD EXPANSION TO THE
DECK...POSSIBLY INTO THE INDY METRO BEFORE THE DECK BEGINS TO MIX
OUT AND SHIFT NORTH. HAVE BUMPED UP CLOUD COVER EXTENSIVELY OVER
THE EASTERN COUNTIES INTO THE AFTERNOON...WITH POTENTIAL FOR SKIES
TO REMAIN CLOUDY FOR MUCH OF THE DAY OVER DELAWARE AND RANDOLPH
COUNTIES.
HAVE PULLED HIGHS DOWN AS MUCH AS 5 DEGREES IN THE NORTHEAST WITH
THE EXPECTED CLOUDS...ANTICIPATE PORTIONS OF DELAWARE AND RANDOLPH
COUNTIES MAY NOT GET MUCH WARMER THAN 26 OR 27. REST UNCHANGED...
PREVIOUS DISCUSSION FOLLOWS.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
ISSUED AT 343 AM EST TUE FEB 10 2015
HIGH PRESSURE WILL SHIFT EAST DURING THE NIGHT TONIGHT AND ALLOW FOR
INCREASING CLOUD COVER AND WARM ADVECTION. A FRONTAL SYSTEM WILL
BEGIN TO APPROACH FROM THE WEST BUT THE FORCING FROM THIS SHOULD
REMAIN UPSTREAM OF THE AREA UNTIL DAYTIME ON WEDNESDAY SO SHOULD
REMAIN DRY THROUGH TONIGHT. WEDNESDAY MORNING FRONTOGENESIS REMAINS
WELL WEST OR NORTHWEST OF THE AREA...HOWEVER THERE IS SOME
INDICATION OF ISENTROPIC LIFT AND SATURATION SHOWING UP ACROSS THE
EASTERN COUNTIES IN BOTH THE NAM AND THE ECMWF. THIS COULD BE AN
INDICATION OF JUST ENOUGH LIFT TO PRODUCE SOME LIGHT SHOWERS THERE
SO WILL ADD A SLIGHT CHANCE AT THIS TIME. TEMPERATURE PROFILES
INDICATE THE WARMING ALOFT WILL OUTPACE THAT AT THE SURFACE SO COULD
SEE A FEW HOURS OF SLEET OR SNOW BEFORE THE COLUMN WARMS ENOUGH FOR
RAIN. A COLD FRONT SHOULD MOVE INTO THE AREA DURING THE
AFTERNOON/EVENING AND THUS MUCH OF THE AREA WILL HAVE A SLIGHT
CHANCE FOR SOME PRECIP...WITH WARM ENOUGH TEMPERATURES TO START AS
RAIN IN THE AFTERNOON AND CHANGE TO A MIX OR ALL SNOW IN THE
EVENING.
WEDNESDAY NIGHT HAS THE BEST FORCING OF THE SHORT
TERM...WITH UPPER FORCING COMBINING WITH THE FRONT STILL IN THE
AREA. THERE IS LITTLE MOISTURE TO WORK WITH SO DON/T EXPECT MUCH IN
THE WAY OF ACCUMULATION BUT THINK THE FORCING LOOKS STRONG ENOUGH TO
PRODUCE A COUPLE TENTHS OF AN INCH AND RAISED POPS FROM CONSENSUS
DURING THIS TIME.
THURSDAY HIGH PRESSURE BEGINS TO BUILD BACK IN AND THE FLOW DURING
THIS TIME COULD BE CONDUCIVE FOR SOME LAKE EFFECT. CONTINUED TO
CARRY LOW CHANCES FOR SNOW ACROSS ALL BUT THE WESTERN COUNTIES
THROUGH THE DAY. THURSDAY NIGHT CONTINUED WITH A CHANCE FOR FLURRIES
IN THE NORTHEAST FOR A FEW HOURS WITH THE LAKE FETCH STILL CONDUCIVE
TO PRODUCING A FEW FLAKES IN THAT AREA.
FOR TEMPERATURES GENERALLY STUCK NEAR A CONSENSUS THROUGH WEDNESDAY.
WENT CLOSER TO THE COLDER END OF THE SOLUTION ENVELOPE FOR WEDNESDAY
NIGHT THROUGH THURSDAY NIGHT WITH STRONG COLD ADVECTION BEHIND THE
ARCTIC FRONT.
&&
.LONG TERM /FRIDAY THROUGH MONDAY NIGHT/...
ISSUED AT 343 AM EST TUE FEB 10 2015
ENSEMBLES ARE STILL VERY CONSISTENT WITH DEPICTING COLD FLOW ACROSS
THE GREAT LAKES AND OHIO VALLEY THROUGH THE MAJORITY OF THIS
PERIOD. ARCTIC AIR ASSOCIATED WITH THIS FLOW WILL CONTINUE TO
PROVIDE WELL BELOW NORMAL TEMPERATURES THROUGH AT LEAST EARLY NEXT
WEEK ALONG WITH VERY DRY AIR. A SHORT WAVE WILL PASS THROUGH THE
AREA FRIDAY THROUGH SATURDAY. THE PERSISTENT DRY AND COLD NORTHERLY
FLOW WILL NOT ALLOW MUCH MOISTURE TO BE IN THE AREA AND PRECIP IS
NOT EXPECTED AT THIS TIME AS THIS SYSTEM PASSES. HOWEVER...LAKE
EFFECT FLURRIES OR SNOW SHOWERS WILL BE POSSIBLE ACROSS THE
NORTHEAST PARTS OF THE FORECAST AREA DURING THE DAY SATURDAY.
THEN LATE IN THE PERIOD...MONDAY NIGHT INTO NEXT TUESDAY A SOUTHERN
STREAM SYSTEM APPEARS TO DEVELOP AND ORGANIZE OVER THE TN VALLEY AND
ALONG WITH SLIGHTLY WARMER FLOW TEMPERATURES WILL MODERATE BACK
TOWARD NORMAL FOR THIS TIME OF YEAR. ALSO CHANCES FOR PRECIP LOOK
MORE PROMISING WITH EITHER SNOW...OR POSSIBLY A MIX OF RAIN/SNOW
BEFORE THIS SYSTEM EXITS THE REGION BY TUESDAY NIGHT.
&&
.AVIATION /DISCUSSION FOR THE 101500Z IND TAF UPDATE/...
VFR CONDITIONS ARE EXPECTED TO CONTINUE. HIGH PRESSURE OVER THE
GREAT LAKES AND RIDGING ALOFT ARE EXPECTED TO CONTINUE TO PROVIDE
SUBSIDENCE...RESULTING IN UNLIMITED CIGS. WILL WATCH IFR CLOUDS
NEAR MUNCIE CLOSELY. THESE CLOUDS MAY ADVECT FROM THE NORTHEAST
AND CLIP THE IND TAF SITE. PROGRESSION IS RATHER SLOW.
/DISCUSSION FOR THE 101200Z TAF ISSUANCE/...
ISSUED AT 604 AM EST TUE FEB 10 2015
LOW LEVEL CLOUDS HAVE SINCE SCATTERED OUT AND VFR CONDITIONS WITH
CLEAR TO MOSTLY CLEAR SKIES ARE THE PREVAILING FLIGHT CATEGORY
THIS MORNING AND WILL CONTINUE TO BE INTO EARLY THIS AFTERNOON.
WINDS WILL BE NORTHEAST/EASTERLY WITH SUSTAINED SPEEDS OF 5 TO 10
KTS. HOWEVER CLOUDS WILL BE ON THE INCREASE TONIGHT AS AN ARCTIC
FRONT IS EXPECTED TO MOVE THROUGH THE AREA WEDNESDAY AFTERNOON AND
EVENING. WINDS WILL BECOME SOUTHERLY WED MORNING AND SW/W AROUND
10-12 KT LATE WED AFTERNOON.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...CP/RYAN
NEAR TERM...RYAN
SHORT TERM...CP
LONG TERM....SMF
AVIATION...SMF
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AREA FORECAST DISCUSSION
NWS WICHITA KS
739 AM CST TUE FEB 10 2015
.UPDATE...
ISSUED AT 739 AM CST TUE FEB 10 2015
CONTINUED TO MONITOR TRENDS AND AREAS OF DENSE FOG IS OVER THE
FLINT HILLS AND MOVING EASTWARD ALONG THE TURNPIKE AND INTO THE
METRO OF WICHITA. CONFIDENCE OVER CENTRAL KANSAS IS LOWER...BUT
COULD SEE EXTENSION TO THOSE AREAS IF TRENDS PERSIST FROM NORTH
CENTRAL KANSAS. WITH CURRENT OBSERVATIONS AND TRENDS...CONFIDENCE
WAS NOT HIGH ENOUGH TO INCLUDE THEM AT THIS TIME...SALINA AND
NORTH AND EAST OF THEM HAS REMAINED WITH VISIBILITIES OF 4 TO 5SM
AND HIGHER.
BILLINGS WRIGHT
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 333 AM CST TUE FEB 10 2015
TODAY-TONIGHT:
EXPECT FOG TO THICKEN OVER THE NEXT COUPLE OF HOURS...ESPECIALLY
IN THE FLINT HILLS...WHERE SATELLITE LOOP SHOWS LOW CLOUDS MOVING
WEST. DO NOT BELIEVE FOG WILL BE AS WIDESPREAD AS YESTERDAY.
TEMPERATURES WILL MAKE SOME RECOVERY TODAY AS WEAK RETURN FLOW
DEVELOPS. COLD FRONT STILL ANTICIPATED TO MOVE THROUGH AREA LATE
TONIGHT/EARLY WED. TEMPERATURES WILL FALL BACK BELOW NORMAL ON
WED. RELATIVELY DRY AIR SHOULD PRECLUDE ANY PRECIPITATION WITH
FRONT.
WED NIGHT-THU:
CHILLY PERIOD WITH COLD AIR ADVECTION PERSISTING WED NIGHT AND
INTO THU WITH LIMITED MIXING. LOWS THU NIGHT WILL BE TRICKY AS
INCREASING RETURN FLOW DEVELOPS IN THE WEST...SO MINIMUMS COULD
OCCUR EARLY THERE. -HOWERTON
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 333 AM CST TUE FEB 10 2015
GFS/ECMWF REMAIN IN SURPRISINGLY GOOD AGREEMENT WITH RIDGE
BUILDING IN THE WESTERN US AND TROUGHING IN THE EAST. BOTH
CONTINUE TO SHOW A LARGE SURFACE HIGH OVERSPREADING THE CENTRAL
US...SENDING MUCH COOLER AIR INTO THE AREA ON SAT...WHICH WILL
PERSIST INTO SUN. THERE WAS SUFFICIENT AGREEMENT BETWEEN MODELS
AND SURROUNDING OFFICES TO HEDGE COOLER THAN GUIDANCE FOR
NOW...ESPECIALLY ON SAT MAXES AND LOWS SUN NIGHT. RETURN FLOW
DEVELOPING SUN NIGHT/MON WILL START ANOTHER WARMING TREND. SMALL
CHANCE OF RAIN ON MON IN SE KS AS LOW LEVEL MOISTURE RETURN NORTH.
-HOWERTON
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 537 AM CST TUE FEB 10 2015
SIMILAR CONCERN THIS MORNING LIKE YESTERDAY MORNING...LOW CEILINGS
AND FOG...DIFFICULT AVIATION FORECAST. LOW CLOUDS HAVE DEVELOPED
OVER SOUTHEAST KANSAS AND ARE STARTING TO SHOW ACROSS CENTRAL AND
SOUTH CENTRAL KANSAS. EXPECT THIS TREND TO CONTINUE THROUGH THE
EARLY MORNING HOURS. THE RR DOES NOT HAVE THE TREND QUITE AS WELL
AS IT DID YESTERDAY...BUT THINK THE TREND WILL BE
SIMILAR...DEVELOPMENT THIS MORNING BETWEEN 12 TO 14Z WITH WORST
CONDITIONS BETWEEN 13 AND 15-16Z AND THEN IMPROVING INTO THE
AFTERNOON HOURS. CEILINGS THAT ARE DEVELOPING OVER SOUTHEAST
KANSAS ARE LIFR AND HAVE NO REASON TO BELIEVE THEY WILL NOT BE
SIMILAR OVER CENTRAL AND SOUTH CENTRAL KANSAS TAF SITES...HAVE
LIFR CEILINGS FOR THIS MORNING IF NOT LIFR...LOW END IFR. HAVE
TRIED TO TIME IT THE BEST I CAN WITH GUIDANCE AND SATELLITE
TRENDS...AND STAYED ON THE PESSIMISTIC SIDE. HAVE TEMPO GROUPS FOR
THE 1/2SM AND FOG...BUT THE LIFR CEILINGS ALREADY TAKE IT INTO THE
LOWEST CATEGORY. NOT AS CONFIDENT IN WIDESPREAD DENSE FOG SO
HOLDING ON THAT FOR NOW.
WINDS WILL SHIFT THIS AFTERNOON AND EVENING AS A FRONT MOVES
THROUGH THE AREA. LOW-MID CLOUDS COULD AGAIN DEVELOP BEHIND THE
FRONT TOWARDS MORNING...ONLY HINTED AT THEM WITH A SCATTERED DECK.
CONFIDENCE IS NOT AS HIGH.
BILLINGS WRIGHT
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 57 38 42 21 / 0 0 0 0
HUTCHINSON 57 38 41 19 / 0 0 10 0
NEWTON 56 37 40 17 / 0 0 0 0
ELDORADO 58 37 41 19 / 0 0 0 0
WINFIELD-KWLD 60 38 44 21 / 0 0 10 0
RUSSELL 58 38 42 18 / 0 0 0 0
GREAT BEND 59 39 42 18 / 0 0 0 0
SALINA 56 37 40 17 / 0 0 0 0
MCPHERSON 56 37 40 18 / 0 0 0 0
COFFEYVILLE 59 38 44 22 / 0 0 0 0
CHANUTE 56 36 40 19 / 0 0 0 0
IOLA 55 35 39 18 / 0 0 0 0
PARSONS-KPPF 57 37 42 20 / 0 0 0 0
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR KSZ051>053-
067>069-083-094.
&&
$$
AREA FORECAST DISCUSSION
NWS WICHITA KS
537 AM CST TUE FEB 10 2015
...UPDATED FOR 12Z AVIATION DISCUSSION...
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 333 AM CST TUE FEB 10 2015
TODAY-TONIGHT:
EXPECT FOG TO THICKEN OVER THE NEXT COUPLE OF HOURS...ESPECIALLY
IN THE FLINT HILLS...WHERE SATELLITE LOOP SHOWS LOW CLOUDS MOVING
WEST. DO NOT BELIEVE FOG WILL BE AS WIDESPREAD AS YESTERDAY.
TEMPERATURES WILL MAKE SOME RECOVERY TODAY AS WEAK RETURN FLOW
DEVELOPS. COLD FRONT STILL ANTICIPATED TO MOVE THROUGH AREA LATE
TONIGHT/EARLY WED. TEMPERATURES WILL FALL BACK BELOW NORMAL ON
WED. RELATIVELY DRY AIR SHOULD PRECLUDE ANY PRECIPITATION WITH
FRONT.
WED NIGHT-THU:
CHILLY PERIOD WITH COLD AIR ADVECTION PERSISTING WED NIGHT AND
INTO THU WITH LIMITED MIXING. LOWS THU NIGHT WILL BE TRICKY AS
INCREASING RETURN FLOW DEVELOPS IN THE WEST...SO MINIMUMS COULD
OCCUR EARLY THERE. -HOWERTON
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 333 AM CST TUE FEB 10 2015
GFS/ECMWF REMAIN IN SURPRISINGLY GOOD AGREEMENT WITH RIDGE
BUILDING IN THE WESTERN US AND TROUGHING IN THE EAST. BOTH
CONTINUE TO SHOW A LARGE SURFACE HIGH OVERSPREADING THE CENTRAL
US...SENDING MUCH COOLER AIR INTO THE AREA ON SAT...WHICH WILL
PERSIST INTO SUN. THERE WAS SUFFICIENT AGREEMENT BETWEEN MODELS
AND SURROUNDING OFFICES TO HEDGE COOLER THAN GUIDANCE FOR
NOW...ESPECIALLY ON SAT MAXES AND LOWS SUN NIGHT. RETURN FLOW
DEVELOPING SUN NIGHT/MON WILL START ANOTHER WARMING TREND. SMALL
CHANCE OF RAIN ON MON IN SE KS AS LOW LEVEL MOISTURE RETURN NORTH.
-HOWERTON
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 537 AM CST TUE FEB 10 2015
SIMILAR CONCERN THIS MORNING LIKE YESTERDAY MORNING...LOW CEILINGS
AND FOG...DIFFICULT AVIATION FORECAST. LOW CLOUDS HAVE DEVELOPED
OVER SOUTHEAST KANSAS AND ARE STARTING TO SHOW ACROSS CENTRAL AND
SOUTH CENTRAL KANSAS. EXPECT THIS TREND TO CONTINUE THROUGH THE
EARLY MORNING HOURS. THE RR DOES NOT HAVE THE TREND QUITE AS WELL
AS IT DID YESTERDAY...BUT THINK THE TREND WILL BE
SIMILAR...DEVELOPMENT THIS MORNING BETWEEN 12 TO 14Z WITH WORST
CONDITIONS BETWEEN 13 AND 15-16Z AND THEN IMPROVING INTO THE
AFTERNOON HOURS. CEILINGS THAT ARE DEVELOPING OVER SOUTHEAST
KANSAS ARE LIFR AND HAVE NO REASON TO BELIEVE THEY WILL NOT BE
SIMILAR OVER CENTRAL AND SOUTH CENTRAL KANSAS TAF SITES...HAVE
LIFR CEILINGS FOR THIS MORNING IF NOT LIFR...LOW END IFR. HAVE
TRIED TO TIME IT THE BEST I CAN WITH GUIDANCE AND SATELLITE
TRENDS...AND STAYED ON THE PESSIMISTIC SIDE. HAVE TEMPO GROUPS FOR
THE 1/2SM AND FOG...BUT THE LIFR CEILINGS ALREADY TAKE IT INTO THE
LOWEST CATEGORY. NOT AS CONFIDENT IN WIDESPREAD DENSE FOG SO
HOLDING ON THAT FOR NOW.
WINDS WILL SHIFT THIS AFTERNOON AND EVENING AS A FRONT MOVES
THROUGH THE AREA. LOW-MID CLOUDS COULD AGAIN DEVELOP BEHIND THE
FRONT TOWARDS MORNING...ONLY HINTED AT THEM WITH A SCATTERED DECK.
CONFIDENCE IS NOT AS HIGH.
BILLINGS WRIGHT
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 57 38 42 21 / 0 0 0 0
HUTCHINSON 57 38 41 19 / 0 0 10 0
NEWTON 56 37 40 17 / 0 0 0 0
ELDORADO 58 37 41 19 / 0 0 0 0
WINFIELD-KWLD 60 38 44 21 / 0 0 10 0
RUSSELL 58 38 42 18 / 0 0 0 0
GREAT BEND 59 39 42 18 / 0 0 0 0
SALINA 56 37 40 17 / 0 0 0 0
MCPHERSON 56 37 40 18 / 0 0 0 0
COFFEYVILLE 59 38 44 22 / 0 0 0 0
CHANUTE 56 36 40 19 / 0 0 0 0
IOLA 55 35 39 18 / 0 0 0 0
PARSONS-KPPF 57 37 42 20 / 0 0 0 0
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
912 AM EST TUE FEB 10 2015
.SYNOPSIS...
A STRENGTHENING LOW PRESSURE SYSTEM WILL REMAIN LARGELY TO THE
SOUTH OF OUR AREA TODAY...AS IT MOVES OFF THE SOUTHERN ATLANTIC
COAST THIS EVENING. HIGH PRESSURE WILL THEN BUILD INTO THE AREA
THROUGH EARLY THURSDAY. AN ARCTIC FRONT IS EXPECTED TO MOVE OVER
THE REGION BY MIDDAY THURSDAY...WITH GUSTY WINDS AND COLD
CANADIAN AIR RESIDING OVER THE REGION THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH 6 PM/...
PCPN DIMINISHING ACRS CWFA...ALTHO A FEW ECHOES LINGERING ACRS THE
TIP OF SRN MD. HRRR CLEARS THAT OUT BTWN 15-16Z. HV XTNDD CALVERT
AND ST MARYS CNTYS TO ACCT FOR THAT. ELSW...HV ALLOWED ADVYS TO
EXPIRE...AS NO NEW PCPN OCCURRING OR XPCTD.
CLOUDS WILL BE LOCKED IN FOR THE REST OF THE DAY WITH THE LOW NEARBY
AND UPPER TROUGH AXIS OVERHEAD...THUS LIMITING TEMP RISE. ON THE
WHOLE VSBYS HAVE BEEN BETTER THAN PREVIOUSLY INDICATED BY GUIDANCE
WITH STEADY WINDS...BUT SOME PATCHY LIGHT FOG REMAINS POSSIBLE.
&&
.SHORT TERM /TONIGHT AND WEDNESDAY/...
A NARROW RIDGE OF HIGH PRESSURE WILL EXTEND SOUTH FROM CANADA
BETWEEN THE DEPARTING COASTAL LOW AND THE NEXT LOW PRESSURE SYSTEM
IN THE UPPER GREAT LAKES TONIGHT INTO WEDNESDAY. THE NORTHERLY
BREEZE WILL LIGHTEN AND CLOUDS WILL DECREASE FOR A BRIEF PERIOD.
SEASONABLE TEMPERATURES ARE EXPECTED...ALTHOUGH GUIDANCE SUGGESTS
LOWER HIGHS FOR WEDNESDAY BY A FEW DEGREES OVER PREVIOUS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
THE MAIN STORY OF THE LONG TERM CONTINUES TO BE THE ONE-TWO SHOTS
OF ARCTIC AIR TO CLOSE OUT THE WEEK AND TO START NEXT WEEK. AN
INTERESTING UPPER-LEVEL INTERACTION WILL CAUSE THE FIRST WAVE...AS
A WEAK CLIPPER MOVING EAST - JUST N OF THE CANADIAN/US BORDER IS
UNDERCUT BY A POTENT VORT SLIDING DOWN FROM THE NORTH. THIS
FEATURE WILL COMBINE W/ THE FORMER AND MAKE FOR A MORE INTENSE
SYSTEM THAT DIVES DOWN ACROSS THE GREAT LAKES FROM LATE WED INTO
THU.
THE INITIAL WAVES OF PRECIP AND THICKER CLOUD DECKS WILL SLIDE
INTO THE APLCNS EARLY ON THU...WHILE BRIEF SURGE OF WARMER AIR
TAKES TEMPS UP INTO THE L40S BEFORE NOONTIME. THE FRONT WILL THEN
MAKE A SWIFT PASSAGE DURING THE MIDDAY HRS...USHERING-IN GUSTY
WINDS AND QUICKLY DROPPING TEMPS BEHIND IT. POSSIBLY ACCUMULATING
SNOWS IN THE HIGHER TERRAIN OF THE APLCNS THU INTO FRI...BUT
ALSO...SCATTERED PRECIP BANDS WILL ALSO BE POSSIBLE E OF THE MTNS.
THE WEAKLY UNSTABLE SITUATION CREATED BY THE RELATIVELY WARMER
AIR OUT AHEAD OF THE FRONT AND THE DYNAMIC COOLING BEHIND...THE
INCOMING COLD UPPER TROUGH WILL BE MORE THAN CAPABLE FOR
DEVELOPING ISOLATED SNOW BANDS THAT STREAK ACROSS THE AREA BUT TOO
FAR OUT IN THE FORECAST TO PREDICT MUCH MORE THAN THE POTENTIAL
FOR THEM.
NOT MUCH RELIEF/RECOVERY OVER THE NEXT COUPLE OF DAYS BEFORE AN
EVEN LARGER/COLDER SYSTEM MOVES ACROSS THE AREA THIS WEEKEND.
HIGHS ON FRI AND SAT WILL BARELY APPROACH THE FREEZING MARK ACROSS
MUCH OF THE REGION W/ BREEZY CONDS PERSISTING AND WIND CHILLS
BECOMING THE MAIN CONCERN NOT ONLY THU NIGHT BEHIND THE ARCTIC
FRONT - BUT EACH NIGHT INTO EARLY NEXT WEEK W/ AMBIENT TEMPS
DROPPING WELL INTO THE TEENS AND 20S. SUB-ZERO WIND CHILLS ARE
EXPECTED ACROSS AT LEAST THE WRN HALF OF THE CWA EACH NIGHT INTO
THE WEEKEND.
&&
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
PCPN HAS ENDED ACRS CWFA. MVFR CIGS REMAIN IN PLACE. LTLCHG XPCTD
THRU THE DAY. CIGS MAY NOT COMPLETELY SCATTER OUT UNTIL THIS
EVENING. VSBYS TRENDING HIGHER WITH A STEADY N WIND...BUT SOME
MVFR POSSIBLE THROUGH AT LEAST THE MORNING.
VFR CONDITIONS WITH LIGHT WINDS EXPECTED TONIGHT/WED.
THE LONGER RANGE FORECAST HAS TWO ARCTIC FRONT PASSAGES - ONE
MIDDAY THU AND ANOTHER THIS COMING WEEKEND. THE THU PASSAGE WILL
QUICKLY DROP TEMPS IN THE AFTN/EVE W/ A SEVERAL-HR PERIOD OF
GUSTY...IF NOT WINDY NW GUSTS IN THE 20-30KT RANGE. SUB-FREEZING
TEMPS WILL BE COMMON WELL INTO THE WEEKEND - W/ SUB-ZERO WIND
CHILLS AT TIMES.
&&
.MARINE...
WNDS LGT NLY ATTM...AS THERES LTL MIXING UNDER LOW CLDS/LGT FZRA.
HWVR WITH LOW PRESSURE OFFSHORE...STEADY N WINDS IN SCA LEVELS
SHOULD DEVELOP TODAY.
INDS WILL BEGIN TO DIMINISH ON THE UPPER TIDAL POTOMAC AND
NORTHERN BAY THIS EVENING...BUT 20 KT GUSTS REMAIN POSSIBLE UNTIL
WEDNESDAY MORNING ON THE CENTRAL/LOWER MD BAY...WHERE THE SCA HAS
BEEN EXTENDED.
A STRONG COLD FRONT WILL SWING THRU THE AREA THU AFTN...USHERING
IN ANOTHER MULTI-DAY PERIOD OF GUSTY WINDS - ESPEC THU NIGHT INTO
FRI. A SIMILAR SCENARIO FROM LATE SAT INTO SUN...W/ GALE POSSIBLE
FOR MUCH OF THESE PERIODS.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
MDZ017-018.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 9 PM EST THIS EVENING FOR
ANZ530>532-539-540.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ535-
536-538.
SMALL CRAFT ADVISORY UNTIL 11 AM EST WEDNESDAY FOR ANZ533-534-
537-541>543.
&&
$$
SYNOPSIS...
NEAR TERM...HTS/ADS
SHORT TERM...ADS
LONG TERM...GMS
AVIATION...HTS/ADS/GMS
MARINE...HTS/ADS/GMS
AREA FORECAST DISCUSSION
NWS DULUTH MN
917 AM CST TUE FEB 10 2015
.UPDATE...
ISSUED AT 917 AM CST TUE FEB 10 2015
BRIEF UPDATE TO ADJUST FOR TEMPERATURE TRENDS. NO MAJOR CHANGE TO
WX ELEMENT GRIDS OR POPS...FORECAST STILL ON TRACK. HAVE RECIEVED
REPORTS OF PRECIP BEGINNING AS SLEET THEN CHANGING TO SNOW...BUT
SINCE THIS WAS ONLY OBSERVED FOR A BRIEF PERIOD HAVE OMITTED FROM
THE FORECAST FOR NOW. HAVE SOME CONCERN ABOUT LACK OF ICE IN
COLUMN...ESPECIALLY IN SOUTHERN PINE COUNTY WHERE IT LOOKS LIKE
PRECIP COULD FALL AS FREEZING RAIN FOR A TIME THIS AFTERNOON PER
THE RAP MODEL. LATER TODAY /LATE AFTERNOON/ THERE WILL BE A PERIOD
OF DRYING ALOFT IN THE SOUTHWEST PART OF THE CWA /BRAINERD LAKES
REGION/ WHICH MEANS ANY PRECIP THAT FALLS COULD FALL AS FREEZING
RAIN/DRIZZLE. ON THIS UPDATE ADDED A MIX OF FREEZING RAIN AND
SNOW INTO THIS AREA...AND WILL TAKE A BETTER LOOK LATER THIS
MORNING AS THE GUIDANCE ROLLS IN AS TO WHETHER OR NOT THIS COULD
BE CHANGED TO JUST FREEZING DRIZZLE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CST TUE FEB 10 2015
THE FOCUS REMAINS ON THE APPROACHING LOW PRESSURE SYSTEM FROM THE
WEST...CURRENTLY IN THE NORTHERN HIGH PLAINS EARLY THIS
MORNING...WHICH IS EXPECTED TO BRING WIDESPREAD LIGHT TO MODERATE
SNOWFALL TO THE NORTHLAND TODAY AND TONIGHT. THE LATEST MODELS
RUNS DID NOT SIGNIFICANTLY CHANGE...SO THE FORECAST IS STILL FOR
WIDESPREAD SNOWFALL OF 3 TO 5 INCHES. THERE IS INCREASING
CONFIDENCE THAT THE FAR EASTERN COUNTIES IN NW WISCONSIN WILL
REACH AROUND 3 TO 4 INCHES...SO WAS ABLE TO ISSUE WINTER WEATHER
ADVISORIES FOR THOSE COUNTIES. THE WHOLE FORECAST AREA IS NOW
UNDER A WINTER WEATHER ADVISORY.
TODAY AND TONIGHT...A LOW PRESSURE SYSTEM IN THE NORTHERN HIGH
PLAINS WILL MOVE EAST THROUGH THE DAKOTAS TODAY...THEN CUT ACROSS
MINNESOTA AND WISCONSIN TONIGHT. THIS STORM SYSTEM IS EXPECTED TO
BRING A WIDESPREAD 3 TO 5 INCHES OF SNOW TO THE NORTHLAND LATE
THIS MORNING THROUGH TONIGHT AS IT MOVES THROUGH THE REGION. THERE
COULD BE LOCALLY HIGHER AMOUNTS OF UP TO AROUND 6 INCHES ALONG THE
MINNESOTA ARROWHEAD NORTH SHORE DUE TO LAKE AND TERRAIN
ENHANCEMENT FROM THE SE TO SOUTH WINDS. THE SNOW WILL GRADUALLY
TAPER OFF TONIGHT...GENERALLY FROM WEST TO EAST. A STRONG
SHORTWAVE AND COLD FRONT WILL SWEEP ACROSS THE NORTHLAND TONIGHT
IN THE WAKE OF THE PASSING SYSTEM. GUSTY NORTHWEST WINDS WILL
DEVELOP IN THE WAKE OF THE FRONT. MODEL SOUNDINGS INDICATE THE
POTENTIAL FOR WIND GUSTS UP TO AROUND 25 MPH LATE TONIGHT.
THERE IS A VERY LOW THREAT OF FREEZING DRIZZLE AT TIMES DURING THE
PASSAGE OF THIS SYSTEM...BUT OVERALL THE THERMAL PROFILE IN MODEL
SOUNDINGS SUGGESTS SNOW IS THE MOST LIKELY PCPN TYPE. THINK THE
MAIN CONCERN FOR FREEZING DRIZZLE IS FOR THE INITIAL ONSET OF THE
PCPN THIS MORNING BEFORE THERE IS MORE RAPID AND WIDESPREAD
SATURATION ALOFT BY THIS AFTERNOON. THE RAP13 AND NAM12 MODEL
SOUNDINGS OVER THE WESTERN FORECAST AREA ARE INDICATING A LOW
LEVEL SATURATED LAYER WITH TEMPERATURES AS COLD AS -6 TO -8
DEGREES CELSIUS...WITH BORDERLINE CONFIDENCE IN SUFFICIENT ICE
CRYSTAL DEPOSITION FROM ALOFT...BEFORE CLEARLY SUPPORTING ALL SNOW
BY LATE THIS MORNING. AT THIS TIME...KEPT THE FORECAST ALL SNOW
THROUGH TONIGHT...BUT WILL NEED TO KEEP A CLOSE EYE ON THE
FREEZING DRIZZLE THREAT.
IT HAS BEEN A RELATIVELY QUIET WINTER FOR A WHILE AND MANY WEEKS
SINCE THE MAJORITY OF THE FORECAST AREA HAS SEEN A SIGNIFICANT
SNOW SYSTEM SUCH AS EXPECTED FOR TODAY. MOTORISTS MAY BE A LITTLE
UNPREPARED AND RUSTY FOR THIS KIND OF WEATHER.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 330 AM CST TUE FEB 10 2015
THE LOW PRESSURE SYSTEM RESPONSIBLE FOR THE SNOW WILL BE LOCATED
DIRECTLY OVER LAKE SUPERIOR BY 12Z WEDNESDAY. SCATTERED SNOW
SHOWERS WILL LINGER IN THE WAKE OF THE LOW PASSAGE...AS INTENSE
COLD ADVECTION ACCOMPANIES A COLD FRONT THAT WILL MOVE THROUGH THE
REGION. SOME DIURNALLY DRIVEN SNOW SHOWERS OR FLURRIES WILL BE
POSSIBLE FOR MOST AREAS ON WEDNESDAY...WITH SNOW SHOWERS BECOMING
LIKELY ALONG THE GOGEBIC RANGE OF IRON COUNTY BY LATE WEDNESDAY.
WINDS BECOME ALMOST DIRECTLY NORTH ACROSS LAKE SUPERIOR BY 00Z
THURSDAY. LIMITING FACTOR INITIALLY WILL BE FAIRLY LOW INVERSION
HEIGHTS BUT THE INVERSION HEIGHTS DO RISE SOMEWHAT BY WEDNESDAY
NIGHT AND WE SHOULD SEE SOME ACCUMULATION ACROSS THE SOUTH SHORE
AS A RESULT. STILL A LOT OF OPEN WATER ACROSS LAKE SUPERIOR. VERY
COLD AIR WILL SETTLE IN ACROSS THE REGION FOR THE LAST HALF OF THE
WORK WEEK AND INTO THE WEEKEND AS ARCTIC HIGH PRESSURE BUILDS INTO
THE NORTHLAND. BY WEDNESDAY NIGHT...H85 TEMPS WILL BE AS LOW AS
-25C WITH SURFACE TEMPS WELL INTO THE TEENS AND 20S BELOW ZERO.
ANOTHER WEAK SYSTEM WILL BRING THE CHANCE FOR LIGHT SNOW ON
THURSDAY NIGHT AND FRIDAY...FOLLOWED BY ANOTHER COLD FRONT FRIDAY
NIGHT. ANOTHER WEAK LOW PRESSURE SYSTEM WILL MOVE THROUGH THURSDAY
NIGHT INTO FRIDAY...WITH MORE LIGHT SNOW. OVERALL IT LOOKS LIKE A
COLD EXTENDED TIME PERIOD...WITH A COUPLE OPPORTUNITIES FOR SOME
LIGHTER SNOWFALL AMOUNTS. NO MAJOR STORMS ARE EXPECTED DURING THIS
TIME FRAME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 549 AM CST TUE FEB 10 2015
A DRAMATIC CHANGE IN WEATHER CONDITIONS WILL HAPPEN AS THE MORNING
WEARS ON...AS WE SEE MVFR TO VFR CIGS GRADUALLY GIVE WAY TO
IFR/LIFR CIGS/VSBYS DUE TO FALLING SNOW. THE SNOW SHOULD COME IN
VERY QUICKLY...RESULTING IN A DRAMATIC REDUCTION IN VISIBILITY AND
LOWERING CIGS. THE SNOW SHOULD BE PERSISTENT THROUGH THE
AFTERNOON...BEFORE DIMINISHING FROM THE WEST. GUSTY NORTHWEST
WINDS WILL DEVELOP BEHIND A COLD FRONT THAT WILL MOVE THROUGH THE
NORTHLAND OVERNIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 26 16 16 -13 / 100 90 20 10
INL 26 5 9 -25 / 100 100 20 10
BRD 28 11 13 -11 / 100 60 10 10
HYR 25 20 22 -10 / 100 90 20 30
ASX 29 19 23 -5 / 100 100 40 70
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR MNZ011-
012-019>021-037-038.
WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR MNZ010-
018-025-026-033>036.
WI...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR WIZ001-
002-006>008.
WINTER WEATHER ADVISORY UNTIL 3 AM CST WEDNESDAY FOR WIZ003-004-
009.
LS...NONE.
&&
$$
UPDATE...JJM
SHORT TERM...GROCHOCINSKI
LONG TERM...DAP
AVIATION...DAP
AREA FORECAST DISCUSSION
NWS HASTINGS NE
651 AM CST TUE FEB 10 2015
.UPDATE...
ISSUED AT 651 AM CST TUE FEB 10 2015
ALTHOUGH STILL FEELING PRETTY CONFIDENT THAN WE WILL GET AWAY
WITHOUT NEEDING ANOTHER DENSE FOG ADVISORY...THE LAST 90 MINUTES
OR SO HAVE BROUGHT ANOTHER UPTICK IN SITES REPORTING VISIBILITY
DOWN TO 1/2 MILE...WITH LOCALIZED SENSORS MAINLY NEAR
PHILLIPSBURG/STOCKTON KS BOUNCING DOWN TO 1/4. ALTHOUGH ONCOMING
DAY SHIFT WILL OBVIOUSLY KEEP AN EYE ON THINGS...FOR NOW WILL JUST
CONTINUE CARRYING LESS-THAN-1-MILE WORDING IN THE PUBLIC FORECAST
AND MENTION 1/2-MILE AND LOCALLY LESS IN THE HAZARDOUS WEATHER
OUTLOOK. IT WILL LIKELY BE A SLOW PROCESS TODAY...BUT STILL
EXPECTING STRATUS AND FOG TO GRADUALLY VACATE MUCH OF THE CWA FROM
WEST-TO-EAST BY EARLY-MID AFTERNOON.
UPDATE ISSUED AT 509 AM CST TUE FEB 10 2015
AS SUGGESTED BELOW LESS THAN 1 HOUR AGO...HAVE OPTED TO CANCEL
THE REMAINDER OF THE DENSE FOG ADVISORY EARLY BASED ON A CONTINUED
OVERALL-IMPROVING TREND SINCE EARLIER IN THE NIGHT. AS OF THIS
WRITING...ONLY 1 OF THE 13 PRIMARY AUTOMATED AIRPORT SENSORS
WITHIN THE CWA (HOLDREGE) IS REPORTING VISIBILITY AS LOW AS 1/2
MILE AND AN ASSORTMENT OF WEB CAMS SUPPORT THE MARKED-IMPROVEMENT
AS WELL. CERTAINLY CANNOT COMPLETELY RULE OUT SOME VERY SMALL
AREAS OF DENSE FOG YET THIS MORNING...ESPECIALLY NEAR THE EDGES OF
THE EXPANSIVE LOW STRATUS DECK STILL SQUARELY PLANTED OVER THE
MAJORITY OF THE CWA...BUT EVEN SO THIS WOULD NOT BE ENOUGH TO
JUSTIFY CONTINUING THE FORMAL HEADLINE.
ON A SEPARATE MINOR NOTE...FORGOT TO MENTION IN THE MAIN
DISCUSSION BELOW THAT FORECASTED AFTERNOON RELATIVE HUMIDITY
VALUES DROP DOWN TO AROUND 25 PERCENT FOR A SHORT TIME IN THE
EXTREME SOUTHWEST CORNER OF THE CWA (FURNAS/PHILLIPS/ROOKS
COUNTIES). IF WEST-NORTHWEST WIND GUSTS THIS AFTERNOON HAPPEN TO
BREACH 20 MPH THIS COULD TECHNICALLY PROMOTE A PERIOD OF NEAR-
CRITICAL FIRE DANGER. HOWEVER...GIVEN THAT IT IS SUCH A SMALL
SPATIAL COVERAGE WITH ONLY MARGINAL-AT-BEST NEAR-CRITICAL
POTENTIAL...WILL FOREGO ANY FORMAL MENTION IN THE HAZARDOUS
WEATHER OUTLOOK PRODUCT (HWOGID).
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 417 AM CST TUE FEB 10 2015
BEFORE STATING ANOTHER WORD...WANT TO SAY THAT THE ONGOING DENSE
FOG ADVISORY FOR MOST OF THE NEBRASKA CWA IS STANDING ON
INCREASINGLY-SHAKY GROUND BASED ON IMPROVING TRENDS THE NEXT FEW
HOURS...AND AN EARLY CANCELLATION BEFORE 5AM NEWS TIME IS
PROBABLY A GOOD BET...AS ALTHOUGH LOCALIZED POCKETS OF DENSE FOG
MIGHT STILL EXIST...THEY ARE CERTAINLY NOT LOOKING WIDESPREAD
ENOUGH TO SUPPORT A FORMAL HEADLINE.
ALTHOUGH ANOTHER SOMEWHAT TRICKY SKY COVER/TEMPERATURE FORECAST IS
IN STORE TODAY...THE ONE GLARING DIFFERENCE BETWEEN NOW AND 24
HOURS AGO IS THAT THE LOW STRATUS/FOG SITUATION IS ON A
DIMINISHING/IMPROVING TREND INSTEAD OF A WORSENING ONE...AND THE
ENTIRE AREA IS EXPECTED TO WARM INTO THE 50S/60S TODAY INSTEAD OF
JUST WESTERN COUNTIES. RUNNING WITH THE ASSUMPTION THAT SKIES
OVER THE CWA SHOULD EXHIBIT A FAIRLY EFFICIENT WEST-TO-EAST AND
IN SOME AREAS A NORTH-TO-SOUTH CLEARING TREND THROUGH MID-
DAY...WE SHOULD NOT BE FACING THE PESKY EXTREMELY SHARP INTERFACE
BETWEEN CLOUDY/SUNNY AREAS THAT LINGERED ALL DAY YESTERDAY. THAT
BEING SAID...WITH EASTERN COUNTIES NEAREST HIGHWAY 81 EXPECTED TO
BE LAST TO SEE APPRECIABLE CLEARING...THESE AREAS SHOULD IN THEORY
REMAIN A BIT COOLER...AND ALSO STAND THE BEST POTENTIAL FOR A
MODEST TEMPERATURE BUST OF 5+ DEGREES.
PRECIPITATION-WISE...OTHER THAN ANY LINGERING LIGHT PATCHY DRIZZLE
OUT THERE THIS MORNING...THE VAST MAJORITY OF THE CWA IS EXPECTED
TO REMAIN DRY THROUGH THESE NEXT 24 HOURS AND THE OFFICIAL
FORECAST REMAINS AS SUCH. THAT BEING SAID...AT LEAST ONE RUN OF
THE NCEP 4KM WRF-NMM SUGGESTS THAT SOME ROGUE SPRINKLES/SPITS OF
DRIZZLE AND MAYBE EVEN A FEW FLURRIES CANNOT BE RULED OUT FROM
LATE THIS AFTERNOON INTO TONIGHT...BUT LACK OF CONFIDENCE IN
OCCURRENCE AND DOUBTS ABOUT HOW MUCH OF THIS LIGHT PRECIP WILL
ACTUALLY REACH THE GROUND HAS PRECLUDED ANY FORMAL FORECAST
MENTION AT THIS TIME. THIS WILL BE SOMETHING FOR THE NEXT FEW
SHIFTS TO KEEP AN EYE ON THOUGH.
ALTHOUGH IT IS EXPECTED TO ESSENTIALLY BE A DRY PASSAGE...THE COLD
FRONT PASSING THROUGH TONIGHT IS DECENTLY-STRONG AND WILL FEATURE
A NOTICEABLE INCREASE IN LATE-NIGHT NORTH WIND...AND SET THE STAGE
FOR A ROUGHLY A 20-DEGREE COOL DOWN FOR WEDNESDAY AS DESCRIBED IN
THE LONG TERM BELOW.
AS FOR THE HERE AND NOW AS OF 1030Z/430AM...ALTHOUGH THE VAST
MAJORITY OF THE CWA REMAINS SOCKED UNDER A VERY LOW STRATUS
DECK...SOME MODEST POCKETS OF CLEARING HAVE BEEN NOTED MAINLY IN
PARTS OF KS ZONES AND ALSO THE THAYER COUNTY AREA. MORE
IMPORTANTLY...INCREASING BOUNDARY-LAYER FLOW THAT IS STARTING TO
TURN MORE SOUTHWESTERLY HAS RESULTED IN IMPROVING VISIBILITY
OVERNIGHT. AS OF THIS WRITING...NEARLY ALL AUTOMATED AIRPORT SITES
IN THE CWA ARE REPORTING VISIBILITY OF NOW-WORSE-THAN ONE-HALF
MILE. ACTUAL SURFACE WIND IS AVERAGING SUSTAINED 10-15 MPH IN MOST
AREAS WITH SOME HIGHER GUSTS MAINLY IN NEB ZONES. EARLIER IN THE
NIGHT AN AREA OF MAINLY ELEVATED RADAR RETURNS BRUSHED ACROSS FAR
NORTHERN ZONES BUT IS CURRENTLY FOCUSED OUTSIDE THE AREA FROM
NORTHEAST NEB NORTHWARD. WOULD NOT BE SHOCKED IF A FEW SLEET
PELLETS/SNOW GRAINS FELL FROM THOSE RADAR ECHOES BUT ITS A NON-
ISSUE NOW. LOW TEMPERATURES THIS MORNING ARE ON TRACK TO BOTTOM
OUT BETWEEN 29-35 IN MOST AREAS. IN THE MID-UPPER LEVELS...WATER
VAPOR SATELLITE AND SHORT TERM MODEL DATA CONFIRM A LOW-AMPLITUDE
SHORTWAVE TRACKING EITHER SIDE OF THE NEB/SD BORDER...PROMOTING
THE LIGHT PRECIP TO THE NORTH. THE ASSOCIATED SURFACE LOW WITH
THAT SYSTEM IS AIDING THE TRANSITION TO MORE SOUTH-SOUTHWESTERLY
SURFACE FLOW THAN THE SOUTHEASTERLY THAT PREVAILED 6-12 HOURS AGO.
MEANWHILE FARTHER NORTH...A SOMEWHAT STRONGER MID LEVEL WAVE IS
SLIPPING EAST-SOUTHEAST OUT OF CANADA INTO ND...AND WILL BE THE
DRIVING FORCE BEHIND THE COLD FRONTAL PASSAGE TONIGHT.
LOOKING FORWARD-FORECAST-WISE IN MORE DETAIL AND STARTING WITH
THE DAYTIME HOURS...ALREADY TOUCHED ON IT ABOVE...BUT THE NUMBER 1
CHALLENGE IS TRYING TO PIN DOWN THE DISSIPATION OF LINGERING
MAINLY LIGHT FOG AND ESPECIALLY THE STILL-EXPANSIVE STRATUS DECK.
ALTHOUGH PRONE TO PLENTY OF SITE-SPECIFIC ERROR...HAVE INDICATED A
FAIRLY- STEADY MAINLY WEST-TO-EAST CLEARING TREND THROUGH MID-
DAY...WITH AT LEAST THE WESTERN 2/3 OF THE CWA LIKELY SEEING
PLENTY OF SUN BY NOON OR SO. THE LATEST HRRR LOW CLOUD PRODUCT
WOULD SUGGEST CLEARING COULD BE EVEN MORE RAPID BUT AM A TOUCH
SKEPTICAL OF THAT. COUNTIES NEAR/ALONG THE HIGHWAY 81 CORRIDOR ARE
MOST PRONE TO SEE AT LEAST HALFWAY-DECENT COVERAGE OF LOW CLOUDS
LINGER INTO EARLY AFTERNOON...BUT WHEN ALL IS SAID AND DONE WOULD
BE SURPRISED IF THE ENTIRE CWA DOES NOT CATCH AT LEAST A FEW HOURS
OF SUN TODAY AS LOW LEVEL FLOW CONTINUES TURNING
WESTERLY/NORTHWESTERLY AND HELPS TO ERODE THE LOW CLOUD MASS. AS A
WEAK TROUGH PASSES THROUGH THE AREA...A GRADUAL TRANSITION FROM
SOUTHERLY TO MORE WESTERLY AND EVENTUALLY NORTHWEST BREEZES WILL
OCCUR TODAY. WHILE SUSTAINED SPEEDS THROUGH MOST OF THE DAY SHOULD
ONLY AVERAGE NO MORE THAN 10-15 MPH WITH SLIGHTLY HIGHER GUSTS.
TEMP-WISE...GENERALLY FOLLOWED A BLEND OF SOME OF THE MOST
OPTIMISTIC MODELS TO YIELD UPPER 50S- MID 60S ACROSS THE MAJORITY
OF THE CWA...BUT HEDGED A BIT COOLER IN FAR EASTERN ZONES WITH
MAINLY MID-50S. OF COURSE...IF LOW STRATUS UNEXPECTEDLY HANGS
AROUND LONGER IN THIS AREA...THIS COULD BE A BIT OPTIMISTIC.
OVERALL THOUGH...UPPED HIGHS ONLY 1-2 DEGREES FROM PREVIOUS
FORECAST. AS EARLIER-STATED...ALTHOUGH NOT IN THE OFFICIAL
FORECAST...SUPPOSE A FEW LATE-DAY SPRINKLES CANNOT BE RULED OUT
MAINLY NORTH OF I-80.
TURNING TO THIS EVENING TONIGHT...THE AFOREMENTIONED DAKOTAS
DISTURBANCE WILL TRACK INTO THE GREAT LAKES REGION...AND BE
REINFORCED BY ANOTHER LOBE OF ENERGY DROPPING SOUTHWARD TOWARD
MN/ND OUT OF CANADA. AGAIN...ALTHOUGH SOME VERY LIGHT/SPOTTY
PRECIP CANNOT BE RULED OUT TONIGHT LOCALLY...BY FAR THE MAIN STORY
WILL BE THE PASSAGE OF A FAIRLY HEALTHY COLD FRONT...WITH 850
MILLIBAR TEMPS BY SUNRISE WEDNESDAY PROGGED TO GENERALLY DROP INTO
THE -3 TO -8 C RANGE OVER MOST OF THE CWA. ALTHOUGH NOT OVERLY-
WINDY...THE ARRIVAL OF THIS FRONT WILL BE MARKED BY SEVERAL HOURS
OF SUSTAINED 15-25 MPH NORTH WIND WITH GUSTS UP TO AROUND 30 MPH.
EXCEPT GENERALLY NORTH OF I-80...THE BRUNT OF THESE STRONGER WINDS
WILL NOT KICK IN UNTIL NEAR/AFTER MIDNIGHT. ALTHOUGH NOT
NECESSARILY EXPECTING ANOTHER TOTALLY-SOLID LOW STRATUS DECK
MOVING IN BEHIND THE FRONT...MODELS SUGGEST A COMBINATION OF
PARTLY- MOSTLY CLOUDY SKIES OVERNIGHT BEHIND THE BOUNDARY...WITH
ANY LOWER STRATUS THAT IS PRESENT POSSIBLY EVEN TRYING TO THROW
OUT A FEW SPITS OF DRIZZLE. AGAIN THOUGH...CONFIDENCE JUST TOO LOW
TO "RUIN" THE CURRENTLY DRY FORECAST. TEMP-WISE...LOWS WILL BE A
LITTLE TRICKY AS WELL...AS FAIRLY PRONOUNCED LOW LEVEL COLD AIR
ADVECTION WILL USHER IN COLDER AIR...BUT ITS FULL POTENTIAL MAY BE
MITIGATED A BIT BY THE INFLUENCE OF LOW LEVEL MIXING FROM THE
STEADY WIND AND ALSO CLOUD COVER. BLENDED A FEW MODELS TOGETHER TO
ESSENTIALLY DROP LOWS A FEW DEGREES IN THE NORTH AND BRING THEM UP
VERY SLIGHTLY SOUTH...AIMING FOR A RANGE FROM MID-20S NORTH OF
I-80 TO MID-30S IN KS ZONES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 417 AM CST TUE FEB 10 2015
FLUCTUATING TEMPERATURES AND MOSTLY DRY CONDITIONS WILL CONTINUE
THROUGH THE EXTENDED PERIODS...WITH ONLY A SMALL CHANCE OF SOME
LIGHT SNOW RETURNING NEXT MONDAY OR TUESDAY.
OVERALL...EXPECT NORTHWESTERLY FLOW ALOFT TO BE DOMINANT THROUGH THE
EXTENDED PERIODS AS A RIDGE OF HIGH PRESSURE BUILDS ACROSS THE WEST
COAST AND MULTIPLE LOW PRESSURE SYSTEMS SWING THROUGH THE OHIO RIVER
VALLEY AND UP THE EAST COAST. THIS GENERAL PATTERN IS FORECAST TO
HOLD THROUGH MOST OF THE EXTENDED...WITH AN UPPER LEVEL DISTURBANCE
PUSHING ACROSS BRITISH COLUMBIA ON SUNDAY FORECAST TO DROP INTO THE
PLAINS EARLY NEXT WEEK. WHILE NOT OVERLY MOIST...THIS SYSTEM WILL
BRING THE BEST CHANCE FOR SOME LIGHT SNOWFALL TO THE LOCAL AREA IN
OVER A WEEK.
STARTING OFF WEDNESDAY...EXPECT BREEZY NORTHERLY WINDS TO BE
ADVECTING COOLER AIR FROM THE NORTH THROUGH THE DAY BEHIND AN EARLY
MORNING COLD FRONT. WHILE NOT BITTERLY COLD...THIS AIRMASS WILL BE
IN STARK CONTRAST TO THIS AFTERNOONS ABOVE NORMAL TEMPERATURES....
LIKELY DROPPING AFTERNOON READINGS VERY CLOSE TO CLIMATOLOGY FOR MID
FEBRUARY. WITH THE ASSOCIATED SURFACE HIGH SLIDING SOUTHEAST ACROSS
THE MISSOURI RIVER VALLEY TO START THE DAY ON THURSDAY...EXPECT A
RETURN TO BELOW NORMAL TEMPERATURES TO START THE DAY...WITH SINGLE
DIGITS FORECAST FOR AT LEAST THE NORTHEASTERN HALF OF THE LOCAL AREA
WHERE THE WINDS WILL BE THE LIGHTEST. WHILE THESE COOL MORNING TEMPS
APPEAR TO BE A SURE THING...AFTERNOON TEMPS ARE A BIT TRICKIER AS
THERE COULD BE A SHARP GRADIENT ACROSS THE LOCAL AREA AS WINDS MAY
BEGIN TO SHIFT LATE IN THE DAY IN RESPONSE TO A SURFACE TROUGH
TRACKING EASTWARD FROM COLORADO. THAT SAID...MODEL CONSENSUS KEEPS
THE WINDS GENERALLY SOUTHERLY BEHIND THE DEPARTING HIGH THROUGH THE
PERIOD OF MAXIMUM HEATING...SO KEPT TEMPS ON THE COOLER SIDE ACROSS
OUR LOCAL AREA THURSDAY AFTERNOON.
THEN AS THE SURFACE TROUGH MOVES ACROSS THE HEART OF THE LOCAL AREA
ON FRIDAY...TEMPERATURES SHOULD SHOOT BACK UP WELL ABOVE NORMAL TO
END THE WEEK...ONLY TO BE BROUGHT BACK DOWN OVER THE UPCOMING
WEEKEND AS A BACKDOOR COLD FRONT WORKS ITS WAY WEST...ASSOCIATED
WITH A VIGOROUS LOW PRESSURE SYSTEM ACROSS THE GREAT LAKES REGION.
WHILE THERE IS SOME DISCREPANCY WITH JUST HOW COLD THIS AIRMASS WILL
BE...TEMPERATURES SHOULD DROP OFF SIGNIFICANTLY...WITH BELOW NORMAL
TEMPERATURES FORECAST FOR SATURDAY...AND ONLY A MODEST WARM UP TO
END THE WEEKEND.
STARTING NEXT WEEK...THE FOCUS WILL SHIFT TO A WEST COAST SYSTEM
THAT WILL BRING ANOTHER COLD FRONT ACROSS THE LOCAL AREA LATE MONDAY
OR TUESDAY...BRINGING ENOUGH MOISTURE TO JUSTIFY THE MENTION FOR A
SMALL CHANCE FOR SOME LIGHT SNOWFALL FOR THE TIME BEING.
OVERALL...THIS DOES NOT APPEAR TO BE A VERY MOIST SYSTEM...BUT WITH
VERY COLD TEMPERATURES...WE COULD SEE SOME LIGHT ACCUMULATIONS AS A
RESULT OF HIGH SNOWFALL RATIOS IF MODEL TRENDS HOLD.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 651 AM CST TUE FEB 10 2015
ALTHOUGH AT LEAST A FEW MORE HOURS OF VERY POOR (MAINLY LIFR/IFR)
CEILING/VISIBILITY CONDITIONS ARE EXPECTED AT BOTH TERMINALS
THIS MORNING IN PERSISTENT FOG/STRATUS...A MARKED IMPROVEMENT IS
EXPECTED BY EARLY AFTERNOON AS A RETURN TO WESTERLY LOW-LEVEL
FLOW SCOURS OUT THE FOG AND STRATUS. CONFIDENCE IN THE TIMING
DETAILS IS ADMITTEDLY A BIT SHAKY...AS IT COULD BE A VERY GRADUAL
IMPROVEMENT OVER TIME OR IT COULD BE A VERY ABRUPT
IMPROVEMENT...SO STAY TUNED FOR AMENDMENTS. AT ANY RATE...HAVE
KEAR RETURNING TO VFR BY 18Z AND KGRI 19Z AS A BEST STAB FOR NOW.
AS FOR WIND...SURFACE BREEZES THIS MORNING WILL REMAIN QUITE
STEADY FROM THE SOUTH-SOUTHWEST...WITH GUST POTENTIAL TO AROUND
20KT. AS A TROUGH AXIS/WEAK COLD FRONT PASSES THROUGH DURING THE
DAY...BREEZES WILL DIMINISH A BIT AND TURN MORE WEST-
NORTHWESTERLY. LATE IN THE PERIOD TONIGHT..STRONGER NORTH-
NORTHWEST WIND WILL ARRIVE BEHIND A COLD FRONT WITH GUST POTENTIAL
TO AROUND 25KT. DURING THE FINAL 6 HOURS...ANOTHER ROUND OF
POTENTIAL MVFR OR EVEN IFR CEILING COULD OVERSPREAD THE AREA FROM
THE NORTH...BUT CONFIDENCE IS LOW AND WENT WITH A LOW-END VFR
CEILING AT THIS TIME. LASTLY...WILL CONTINUE A SOMEWHAT MARGINAL
MENTION OF LOW LEVEL WIND SHEAR (LLWS) FOR A FEW MORE HOURS AT
KGRI THIS MORNING TO ACCOUNT FOR A GENERALLY 30KT BULK SHEAR
DIFFERENCE BETWEEN THE SURFACE AND ROUGHLY 1500 FT AGL...THANKS TO
SOUTHWESTERLY WIND TOPPING OUT AROUND 40KT AT THIS LEVEL. HAVE
OMITTED THIS LLWS MENTION FROM KEAR GIVEN THAT BULK SHEAR
DIFFERENCE SHOULD BE LESS LIKELY TO EXCEED 30KT BUT IT WILL STILL
BE CLOSE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...PFANNKUCH
SHORT TERM...PFANNKUCH
LONG TERM...ROSSI
AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
520 AM CST TUE FEB 10 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 322 AM CST TUE FEB 10 2015
LOW PRESSURE ACROSS SCNTL SD IS EXPECTED TO CLEAR THE FCST AREA
OF LOW CLOUDS AND FOG BY 15Z THIS AM. FOG PRODUCTION IN THE DENSE
FOG ADVISORY AREA HAS BE BEEN LIMITED BY MIXING FROM STRONG SFC
WINDS AND POOR RADIATION FROM A BATCH OF MID LEVEL CLOUDS ALOFT.
THE RAP...ETAL MODELS INDICATES FAIRLY STRONG WEST WINDS WILL
DEVELOP BY 12Z SCOURING THE AREA OF MOISTURE AND SHUNTING THE FOG
EAST. THUS THE PROBABILITY OF DENSE FOG APPEARS LOW IN ALL SOLNS.
THE RAP WAS THE WARMEST MODEL AND WAS USED FOR THE TEMPERATURE
FORECAST TODAY FOR HIGHS IN THE UPPER 50S TO MID 60S. NORTHWEST
WINDS WILL BE INCREASING TO 15 TO 25 MPH IN THE WAKE OF THE SFC LOW
ACROSS SD. A TANDEM LOW ACROSS ERN MT WILL MOVE INTO CNTL ND THIS
AFTN AND SEND A COLD FRONT TOWARD NRN NEB. THE MODELS SHOW WEAK
CONVERGENCE AROUND THE LEE SIDE OF THE BLACK HILLS AS THE FRONT
APPROACHES AND THIS MIGHT BE ENOUGH FOR SPRINKLES ACROSS NRN
SHERIDAN COUNTY AND WRN CHERRY COUNTY. THE HRRR...GEM REGIONAL AND
RAP SUPPORT THIS RAIN CHANCE ALBEIT NON-MEASURABLE.
NORTHWEST WINDS SHOULD REMAIN STRONG TONIGHT AS AN ARCTIC COLD FRONT
MOVES THROUGH THE FCST AREA. THE MODELS SHOW WIND SPEEDS INCREASING
FROM 06Z ONWARD ACROSS THE NORTH AND H850MB TEMPERATURES FALLING TO
AROUND -7C BY MORNING WHICH MIGHT SUPPORT LOWS IN THE LOWER 20S
NORTH AND WARMER READINGS IN THE MID AND UPPER 20S TO NEAR 30 SOUTH.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 322 AM CST TUE FEB 10 2015
PRIMARY FORECAST CONCERNS FOR THIS PORTION OF THE FORECAST PERIOD
DEAL WITH TEMPERATURES THROUGHOUT...THEN WITH CHANCES FOR SNOW FOR
EARLY NEXT WEEK.
MODELS ARE IN GOOD AGREEMENT FOR MUCH OF THE FORECAST PERIOD WITH
ONLY MINOR DETAILS SEEN TO IMPACT THE FORECAST. THAT BEING
SAID...EVEN SOME MINOR DIFFERENCES COULD HAVE AN IMPACT ON THE
SENSIBLE WEATHER...MAINLY THE CLOUD COVER AND WINDS...WHICH IN TURN
CAN IMPACT THE TEMPERATURE FORECAST.
THE PERIOD BEGINS ON WEDNESDAY...WITH THE UPPER LEVEL SHORTWAVE
TROUGH WHICH IS NOW OVER THE NORTHWEST TERRITORIES DIGGING SOUTH
INTO THE UPPER MISSISSIPPI RIVER VALLEY REGION. THIS WILL PUSH A
GOOD COLD FRONT THROUGH THE REGION BY 12Z WEDNESDAY. THE TRACK OF
THE MAIN PV ANOMALY EMBEDDED IN THE SHORTWAVE STAYS WELL NORTH AND
EAST OF THE LOCAL AREA BUT THIS WILL LIKELY STILL ENHANCE THE
DOWNWARD MOTION/SUBSIDENCE...DRYING AND COLD AIR ADVECTION DURING
THE DAY TO AT LEAST HELP THE LOW LEVEL MIXING AND BRING ABOUT BREEZY
NORTHWEST WINDS. WITH THE COLD AIR ADVECTION BEHIND THE
FRONT...WEDNESDAY WILL BE QUITE A BIT COOLER THAN WHAT HAS BEEN
EXPERIENCED OVER THE PAST FEW DAYS...WITH HIGHS NEAR NORMAL MOST
PLACES. THE MODELS ARE SHOWING SOME WARMING ALOFT BY THE END OF THE
DAY WEDNESDAY WHICH COULD LEAD TO SLIGHTLY WARMER TEMPERATURES OVER
SOUTHWEST NEBRASKA. THE FORECAST WILL KEEP MID 40S FOR THESE AREAS
WITH LOW 30S OVER NORTH CENTRAL NEBRASKA ON WEDNESDAY.
THE SURFACE HIGH BEHIND THE SYSTEM BUILDS SOUTH INTO THE NORTHERN
PLAINS WEDNESDAY NIGHT...THEN INTO THE MISSISSIPPI RIVER VALLEY ON
THURSDAY. WITH THE COLD AIR ASSOCIATED WITH THE SURFACE
HIGH...TEMPERATURES WILL BE FAIRLY COLD WEDNESDAY NIGHT. THE COLDEST
AIR ALOFT WILL REMAIN ACROSS EASTERN NEBRASKA AND AS THOSE LOCATIONS
WILL BE CLOSER TO THE CENTER OF THE HIGH...WINDS WILL BE LIGHTER
WHICH SHOULD PROMOTE BETTER RADIATIONAL COOLING. FURTHER
WEST...RETURN FLOW SOUTHERLY WINDS SET UP AND ALTHOUGH WILL BE
LIGHT...ARE NOT EXPECTED TO COMPLETELY DROP OFF. THESE CONDITIONS
WILL CREATE A DECENT TEMPERATURE GRADIENT ACROSS THE FORECAST
AREA...FROM THE LOW SINGLE DIGITS TO AROUND 20 DEGREES.
FOR THURSDAY...THE NAM IS A BIT QUICKER THAN THE REMAINDER OF THE
MODEL SOLUTIONS WITH A WARM FRONT MOVING INTO NEBRASKA ON THURSDAY.
TIMING OF THIS FRONT WILL MAKE A DIFFERENCE IN TEMPERATURES DURING
THE AFTERNOON AS 850MB TEMPERATURES INCREASE TO AROUND 10C...WHILE
WEST-NORTHWEST FLOW AT THE SURFACE WILL HELP TO ENHANCE THE MIXING
POTENTIAL AND HELP WARM THINGS UP. HOWEVER...IF THE FRONT IS
SLOWER...COOLER TEMPERATURES WILL BE MAINTAINED THROUGH THE DAY. FOR
THE FORECAST...DID INCREASE HIGHS OVER THE WESTERN PART OF THE
FORECAST AREA AS CONFIDENCE IS HIGHER ON A BIT FASTER MOVEMENT AND
WITH A WARM BIAS THAT HAS BEEN SEEN LATELY IN OBSERVATIONS.
BY THIS POINT IN TIME...THE UPPER LEVEL FLOW ACROSS THE CONUS WILL
BE QUITE AMPLIFIED WITH A DEEP TROUGH OVER THE EAST COAST AND A
STRONG RIDGE OVER THE WESTERN CONUS. THIS PUTS THE LOCAL AREA WITHIN
NORTHWEST FLOW WHICH WILL BRING MULTIPLE SHORTWAVE TROUGHS ACROSS
THE AREA THROUGH THE REMAINDER OF THE FORECAST PERIOD. WHILE
MOISTURE WITH THE MAJORITY OF THESE SYSTEMS STAYS WELL NORTH OF THE
AREA TO KEEP THE FORECAST DRY...DESPITE PERIODS OF STRONGER LIFT.
WHAT WILL OCCUR IS LIKELY A BACK AND FORTH TREND FOR TEMPERATURES.
FRIDAY AND SUNDAY LOOK LIKE WARMER DAYS...WHILE SATURDAY AND MONDAY
WILL BE COOLER AS THE AREA WILL SIT IN THE WAKE OF WEAK SYSTEMS WITH
COLD AIR ADVECTION TO WORK WITH.
THE NEXT CHANCES FOR MEASURABLE PRECIPITATION WILL COME ON MONDAY.
THE UPPER LEVEL PATTERN DAMPENS OUT WITH MORE BROAD WEST TO
NORTHWEST FLOW IN PLACE. THE MODELS CONTINUE TO BE IN DECENT
AGREEMENT THIS FAR OUT BRINGING A WEAK SHORTWAVE TROUGH ACROSS
NEBRASKA AND SOUTH DAKOTA. THE MODELS ARE SHOWING A NEARLY COUPLED
RIGHT OVER-TOP OF THE FORECAST AREA WHICH SHOULD LEAD TO STRONGER
LIFT OVER THE AREA. IN ADDITION...DEEP LAYER MOISTURE INCREASES SO
AT THIS TIME WILL CONTINUE WITH MENTION OF PRECIPITATION FOR EARLY
IN THE WEEK. WITH COLD AIR ADVECTION THROUGH THE DAY
MONDAY...SOUNDINGS AND TEMPERATURE PROFILES WOULD INDICATE THE
PRECIPITATION WILL FALL AS SNOW SO ONLY HAVE THAT MENTION IN THE
FORECAST AT THIS TIME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 520 AM CST TUE FEB 10 2015
THE BANK OF LIFR/IFR CIGS FROM STOCKVILLE TO ONEILL SHOULD EXIT
THE FCST AREA BY 15Z. THEREAFTER VFR IS EXPECTED ALL AREAS THROUGH
06Z TONIGHT. THEREAFTER...THE SREF SUGGESTS MVFR CIGS MAY DEVELOP
FROM KVTN-KONL ASSOCIATED WITH AN ARCTIC HIGH BUILDING INTO NRN
NEB. VFR IS EXPECTED ELSEWHERE.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...BROOKS
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS HASTINGS NE
509 AM CST TUE FEB 10 2015
.UPDATE...
ISSUED AT 509 AM CST TUE FEB 10 2015
AS SUGGESTED BELOW LESS THAN 1 HOUR AGO...HAVE OPTED TO CANCEL
THE REMAINDER OF THE DENSE FOG ADVISORY EARLY BASED ON A CONTINUED
OVERALL-IMPROVING TREND SINCE EARLIER IN THE NIGHT. AS OF THIS
WRITING...ONLY 1 OF THE 13 PRIMARY AUTOMATED AIRPORT SENSORS
WITHIN THE CWA (HOLDREGE) IS REPORTING VISIBILITY AS LOW AS 1/2
MILE AND AN ASSORTMENT OF WEB CAMS SUPPORT THE MARKED-IMPROVEMENT
AS WELL. CERTAINLY CANNOT COMPLETELY RULE OUT SOME VERY SMALL
AREAS OF DENSE FOG YET THIS MORNING...ESPECIALLY NEAR THE EDGES OF
THE EXPANSIVE LOW STRATUS DECK STILL SQUARELY PLANTED OVER THE
MAJORITY OF THE CWA...BUT EVEN SO THIS WOULD NOT BE ENOUGH TO
JUSTIFY CONTINUING THE FORMAL HEADLINE.
ON A SEPARATE MINOR NOTE...FORGOT TO MENTION IN THE MAIN
DISCUSSION BELOW THAT FORECASTED AFTERNOON RELATIVE HUMIDITY
VALUES DROP DOWN TO AROUND 25 PERCENT FOR A SHORT TIME IN THE
EXTREME SOUTHWEST CORNER OF THE CWA (FURNAS/PHILLIPS/ROOKS
COUNTIES). IF WEST-NORTHWEST WIND GUSTS THIS AFTERNOON HAPPEN TO
BREACH 20 MPH THIS COULD TECHNICALLY PROMOTE A PERIOD OF NEAR-
CRITICAL FIRE DANGER. HOWEVER...GIVEN THAT IT IS SUCH A SMALL
SPATIAL COVERAGE WITH ONLY MARGINAL-AT-BEST NEAR-CRITICAL
POTENTIAL...WILL FOREGO ANY FORMAL MENTION IN THE HAZARDOUS
WEATHER OUTLOOK PRODUCT (HWOGID).
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 417 AM CST TUE FEB 10 2015
BEFORE STATING ANOTHER WORD...WANT TO SAY THAT THE ONGOING DENSE
FOG ADVISORY FOR MOST OF THE NEBRASKA CWA IS STANDING ON
INCREASINGLY-SHAKY GROUND BASED ON IMPROVING TRENDS THE NEXT FEW
HOURS...AND AN EARLY CANCELLATION BEFORE 5AM NEWS TIME IS
PROBABLY A GOOD BET...AS ALTHOUGH LOCALIZED POCKETS OF DENSE FOG
MIGHT STILL EXIST...THEY ARE CERTAINLY NOT LOOKING WIDESPREAD
ENOUGH TO SUPPORT A FORMAL HEADLINE.
ALTHOUGH ANOTHER SOMEWHAT TRICKY SKY COVER/TEMPERATURE FORECAST IS
IN STORE TODAY...THE ONE GLARING DIFFERENCE BETWEEN NOW AND 24
HOURS AGO IS THAT THE LOW STRATUS/FOG SITUATION IS ON A
DIMINISHING/IMPROVING TREND INSTEAD OF A WORSENING ONE...AND THE
ENTIRE AREA IS EXPECTED TO WARM INTO THE 50S/60S TODAY INSTEAD OF
JUST WESTERN COUNTIES. RUNNING WITH THE ASSUMPTION THAT SKIES
OVER THE CWA SHOULD EXHIBIT A FAIRLY EFFICIENT WEST-TO-EAST AND
IN SOME AREAS A NORTH-TO-SOUTH CLEARING TREND THROUGH MID-
DAY...WE SHOULD NOT BE FACING THE PESKY EXTREMELY SHARP INTERFACE
BETWEEN CLOUDY/SUNNY AREAS THAT LINGERED ALL DAY YESTERDAY. THAT
BEING SAID...WITH EASTERN COUNTIES NEAREST HIGHWAY 81 EXPECTED TO
BE LAST TO SEE APPRECIABLE CLEARING...THESE AREAS SHOULD IN THEORY
REMAIN A BIT COOLER...AND ALSO STAND THE BEST POTENTIAL FOR A
MODEST TEMPERATURE BUST OF 5+ DEGREES.
PRECIPITATION-WISE...OTHER THAN ANY LINGERING LIGHT PATCHY DRIZZLE
OUT THERE THIS MORNING...THE VAST MAJORITY OF THE CWA IS EXPECTED
TO REMAIN DRY THROUGH THESE NEXT 24 HOURS AND THE OFFICIAL
FORECAST REMAINS AS SUCH. THAT BEING SAID...AT LEAST ONE RUN OF
THE NCEP 4KM WRF-NMM SUGGESTS THAT SOME ROGUE SPRINKLES/SPITS OF
DRIZZLE AND MAYBE EVEN A FEW FLURRIES CANNOT BE RULED OUT FROM
LATE THIS AFTERNOON INTO TONIGHT...BUT LACK OF CONFIDENCE IN
OCCURRENCE AND DOUBTS ABOUT HOW MUCH OF THIS LIGHT PRECIP WILL
ACTUALLY REACH THE GROUND HAS PRECLUDED ANY FORMAL FORECAST
MENTION AT THIS TIME. THIS WILL BE SOMETHING FOR THE NEXT FEW
SHIFTS TO KEEP AN EYE ON THOUGH.
ALTHOUGH IT IS EXPECTED TO ESSENTIALLY BE A DRY PASSAGE...THE COLD
FRONT PASSING THROUGH TONIGHT IS DECENTLY-STRONG AND WILL FEATURE
A NOTICEABLE INCREASE IN LATE-NIGHT NORTH WIND...AND SET THE STAGE
FOR A ROUGHLY A 20-DEGREE COOL DOWN FOR WEDNESDAY AS DESCRIBED IN
THE LONG TERM BELOW.
AS FOR THE HERE AND NOW AS OF 1030Z/430AM...ALTHOUGH THE VAST
MAJORITY OF THE CWA REMAINS SOCKED UNDER A VERY LOW STRATUS
DECK...SOME MODEST POCKETS OF CLEARING HAVE BEEN NOTED MAINLY IN
PARTS OF KS ZONES AND ALSO THE THAYER COUNTY AREA. MORE
IMPORTANTLY...INCREASING BOUNDARY-LAYER FLOW THAT IS STARTING TO
TURN MORE SOUTHWESTERLY HAS RESULTED IN IMPROVING VISIBILITY
OVERNIGHT. AS OF THIS WRITING...NEARLY ALL AUTOMATED AIRPORT SITES
IN THE CWA ARE REPORTING VISIBILITY OF NOW-WORSE-THAN ONE-HALF
MILE. ACTUAL SURFACE WIND IS AVERAGING SUSTAINED 10-15 MPH IN MOST
AREAS WITH SOME HIGHER GUSTS MAINLY IN NEB ZONES. EARLIER IN THE
NIGHT AN AREA OF MAINLY ELEVATED RADAR RETURNS BRUSHED ACROSS FAR
NORTHERN ZONES BUT IS CURRENTLY FOCUSED OUTSIDE THE AREA FROM
NORTHEAST NEB NORTHWARD. WOULD NOT BE SHOCKED IF A FEW SLEET
PELLETS/SNOW GRAINS FELL FROM THOSE RADAR ECHOES BUT ITS A NON-
ISSUE NOW. LOW TEMPERATURES THIS MORNING ARE ON TRACK TO BOTTOM
OUT BETWEEN 29-35 IN MOST AREAS. IN THE MID-UPPER LEVELS...WATER
VAPOR SATELLITE AND SHORT TERM MODEL DATA CONFIRM A LOW-AMPLITUDE
SHORTWAVE TRACKING EITHER SIDE OF THE NEB/SD BORDER...PROMOTING
THE LIGHT PRECIP TO THE NORTH. THE ASSOCIATED SURFACE LOW WITH
THAT SYSTEM IS AIDING THE TRANSITION TO MORE SOUTH-SOUTHWESTERLY
SURFACE FLOW THAN THE SOUTHEASTERLY THAT PREVAILED 6-12 HOURS AGO.
MEANWHILE FARTHER NORTH...A SOMEWHAT STRONGER MID LEVEL WAVE IS
SLIPPING EAST-SOUTHEAST OUT OF CANADA INTO ND...AND WILL BE THE
DRIVING FORCE BEHIND THE COLD FRONTAL PASSAGE TONIGHT.
LOOKING FORWARD-FORECAST-WISE IN MORE DETAIL AND STARTING WITH
THE DAYTIME HOURS...ALREADY TOUCHED ON IT ABOVE...BUT THE NUMBER 1
CHALLENGE IS TRYING TO PIN DOWN THE DISSIPATION OF LINGERING
MAINLY LIGHT FOG AND ESPECIALLY THE STILL-EXPANSIVE STRATUS DECK.
ALTHOUGH PRONE TO PLENTY OF SITE-SPECIFIC ERROR...HAVE INDICATED A
FAIRLY- STEADY MAINLY WEST-TO-EAST CLEARING TREND THROUGH MID-
DAY...WITH AT LEAST THE WESTERN 2/3 OF THE CWA LIKELY SEEING
PLENTY OF SUN BY NOON OR SO. THE LATEST HRRR LOW CLOUD PRODUCT
WOULD SUGGEST CLEARING COULD BE EVEN MORE RAPID BUT AM A TOUCH
SKEPTICAL OF THAT. COUNTIES NEAR/ALONG THE HIGHWAY 81 CORRIDOR ARE
MOST PRONE TO SEE AT LEAST HALFWAY-DECENT COVERAGE OF LOW CLOUDS
LINGER INTO EARLY AFTERNOON...BUT WHEN ALL IS SAID AND DONE WOULD
BE SURPRISED IF THE ENTIRE CWA DOES NOT CATCH AT LEAST A FEW HOURS
OF SUN TODAY AS LOW LEVEL FLOW CONTINUES TURNING
WESTERLY/NORTHWESTERLY AND HELPS TO ERODE THE LOW CLOUD MASS. AS A
WEAK TROUGH PASSES THROUGH THE AREA...A GRADUAL TRANSITION FROM
SOUTHERLY TO MORE WESTERLY AND EVENTUALLY NORTHWEST BREEZES WILL
OCCUR TODAY. WHILE SUSTAINED SPEEDS THROUGH MOST OF THE DAY SHOULD
ONLY AVERAGE NO MORE THAN 10-15 MPH WITH SLIGHTLY HIGHER GUSTS.
TEMP-WISE...GENERALLY FOLLOWED A BLEND OF SOME OF THE MOST
OPTIMISTIC MODELS TO YIELD UPPER 50S- MID 60S ACROSS THE MAJORITY
OF THE CWA...BUT HEDGED A BIT COOLER IN FAR EASTERN ZONES WITH
MAINLY MID-50S. OF COURSE...IF LOW STRATUS UNEXPECTEDLY HANGS
AROUND LONGER IN THIS AREA...THIS COULD BE A BIT OPTIMISTIC.
OVERALL THOUGH...UPPED HIGHS ONLY 1-2 DEGREES FROM PREVIOUS
FORECAST. AS EARLIER-STATED...ALTHOUGH NOT IN THE OFFICIAL
FORECAST...SUPPOSE A FEW LATE-DAY SPRINKLES CANNOT BE RULED OUT
MAINLY NORTH OF I-80.
TURNING TO THIS EVENING TONIGHT...THE AFOREMENTIONED DAKOTAS
DISTURBANCE WILL TRACK INTO THE GREAT LAKES REGION...AND BE
REINFORCED BY ANOTHER LOBE OF ENERGY DROPPING SOUTHWARD TOWARD
MN/ND OUT OF CANADA. AGAIN...ALTHOUGH SOME VERY LIGHT/SPOTTY
PRECIP CANNOT BE RULED OUT TONIGHT LOCALLY...BY FAR THE MAIN STORY
WILL BE THE PASSAGE OF A FAIRLY HEALTHY COLD FRONT...WITH 850
MILLIBAR TEMPS BY SUNRISE WEDNESDAY PROGGED TO GENERALLY DROP INTO
THE -3 TO -8 C RANGE OVER MOST OF THE CWA. ALTHOUGH NOT OVERLY-
WINDY...THE ARRIVAL OF THIS FRONT WILL BE MARKED BY SEVERAL HOURS
OF SUSTAINED 15-25 MPH NORTH WIND WITH GUSTS UP TO AROUND 30 MPH.
EXCEPT GENERALLY NORTH OF I-80...THE BRUNT OF THESE STRONGER WINDS
WILL NOT KICK IN UNTIL NEAR/AFTER MIDNIGHT. ALTHOUGH NOT
NECESSARILY EXPECTING ANOTHER TOTALLY-SOLID LOW STRATUS DECK
MOVING IN BEHIND THE FRONT...MODELS SUGGEST A COMBINATION OF
PARTLY- MOSTLY CLOUDY SKIES OVERNIGHT BEHIND THE BOUNDARY...WITH
ANY LOWER STRATUS THAT IS PRESENT POSSIBLY EVEN TRYING TO THROW
OUT A FEW SPITS OF DRIZZLE. AGAIN THOUGH...CONFIDENCE JUST TOO LOW
TO "RUIN" THE CURRENTLY DRY FORECAST. TEMP-WISE...LOWS WILL BE A
LITTLE TRICKY AS WELL...AS FAIRLY PRONOUNCED LOW LEVEL COLD AIR
ADVECTION WILL USHER IN COLDER AIR...BUT ITS FULL POTENTIAL MAY BE
MITIGATED A BIT BY THE INFLUENCE OF LOW LEVEL MIXING FROM THE
STEADY WIND AND ALSO CLOUD COVER. BLENDED A FEW MODELS TOGETHER TO
ESSENTIALLY DROP LOWS A FEW DEGREES IN THE NORTH AND BRING THEM UP
VERY SLIGHTLY SOUTH...AIMING FOR A RANGE FROM MID-20S NORTH OF
I-80 TO MID-30S IN KS ZONES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 417 AM CST TUE FEB 10 2015
FLUCTUATING TEMPERATURES AND MOSTLY DRY CONDITIONS WILL CONTINUE
THROUGH THE EXTENDED PERIODS...WITH ONLY A SMALL CHANCE OF SOME
LIGHT SNOW RETURNING NEXT MONDAY OR TUESDAY.
OVERALL...EXPECT NORTHWESTERLY FLOW ALOFT TO BE DOMINANT THROUGH THE
EXTENDED PERIODS AS A RIDGE OF HIGH PRESSURE BUILDS ACROSS THE WEST
COAST AND MULTIPLE LOW PRESSURE SYSTEMS SWING THROUGH THE OHIO RIVER
VALLEY AND UP THE EAST COAST. THIS GENERAL PATTERN IS FORECAST TO
HOLD THROUGH MOST OF THE EXTENDED...WITH AN UPPER LEVEL DISTURBANCE
PUSHING ACROSS BRITISH COLUMBIA ON SUNDAY FORECAST TO DROP INTO THE
PLAINS EARLY NEXT WEEK. WHILE NOT OVERLY MOIST...THIS SYSTEM WILL
BRING THE BEST CHANCE FOR SOME LIGHT SNOWFALL TO THE LOCAL AREA IN
OVER A WEEK.
STARTING OFF WEDNESDAY...EXPECT BREEZY NORTHERLY WINDS TO BE
ADVECTING COOLER AIR FROM THE NORTH THROUGH THE DAY BEHIND AN EARLY
MORNING COLD FRONT. WHILE NOT BITTERLY COLD...THIS AIRMASS WILL BE
IN STARK CONTRAST TO THIS AFTERNOONS ABOVE NORMAL TEMPERATURES....
LIKELY DROPPING AFTERNOON READINGS VERY CLOSE TO CLIMATOLOGY FOR MID
FEBRUARY. WITH THE ASSOCIATED SURFACE HIGH SLIDING SOUTHEAST ACROSS
THE MISSOURI RIVER VALLEY TO START THE DAY ON THURSDAY...EXPECT A
RETURN TO BELOW NORMAL TEMPERATURES TO START THE DAY...WITH SINGLE
DIGITS FORECAST FOR AT LEAST THE NORTHEASTERN HALF OF THE LOCAL AREA
WHERE THE WINDS WILL BE THE LIGHTEST. WHILE THESE COOL MORNING TEMPS
APPEAR TO BE A SURE THING...AFTERNOON TEMPS ARE A BIT TRICKIER AS
THERE COULD BE A SHARP GRADIENT ACROSS THE LOCAL AREA AS WINDS MAY
BEGIN TO SHIFT LATE IN THE DAY IN RESPONSE TO A SURFACE TROUGH
TRACKING EASTWARD FROM COLORADO. THAT SAID...MODEL CONSENSUS KEEPS
THE WINDS GENERALLY SOUTHERLY BEHIND THE DEPARTING HIGH THROUGH THE
PERIOD OF MAXIMUM HEATING...SO KEPT TEMPS ON THE COOLER SIDE ACROSS
OUR LOCAL AREA THURSDAY AFTERNOON.
THEN AS THE SURFACE TROUGH MOVES ACROSS THE HEART OF THE LOCAL AREA
ON FRIDAY...TEMPERATURES SHOULD SHOOT BACK UP WELL ABOVE NORMAL TO
END THE WEEK...ONLY TO BE BROUGHT BACK DOWN OVER THE UPCOMING
WEEKEND AS A BACKDOOR COLD FRONT WORKS ITS WAY WEST...ASSOCIATED
WITH A VIGOROUS LOW PRESSURE SYSTEM ACROSS THE GREAT LAKES REGION.
WHILE THERE IS SOME DISCREPANCY WITH JUST HOW COLD THIS AIRMASS WILL
BE...TEMPERATURES SHOULD DROP OFF SIGNIFICANTLY...WITH BELOW NORMAL
TEMPERATURES FORECAST FOR SATURDAY...AND ONLY A MODEST WARM UP TO
END THE WEEKEND.
STARTING NEXT WEEK...THE FOCUS WILL SHIFT TO A WEST COAST SYSTEM
THAT WILL BRING ANOTHER COLD FRONT ACROSS THE LOCAL AREA LATE MONDAY
OR TUESDAY...BRINGING ENOUGH MOISTURE TO JUSTIFY THE MENTION FOR A
SMALL CHANCE FOR SOME LIGHT SNOWFALL FOR THE TIME BEING.
OVERALL...THIS DOES NOT APPEAR TO BE A VERY MOIST SYSTEM...BUT WITH
VERY COLD TEMPERATURES...WE COULD SEE SOME LIGHT ACCUMULATIONS AS A
RESULT OF HIGH SNOWFALL RATIOS IF MODEL TRENDS HOLD.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1214 AM CST TUE FEB 10 2015
ALTHOUGH SEVERAL MORE HOURS OF VERY POOR (MAINLY LIFR)
CEILING/VISIBILITY CONDITIONS ARE EXPECTED AT BOTH TERMINALS
THROUGH THESE FIRST SEVERAL HOURS THIS MORNING IN PERSISTENT
FOG/STRATUS/LIGHT DRIZZLE...A MARKED IMPROVEMENT IS EXPECTED FOR
BY THE LATTER HALF OF THE PERIOD AS A RETURN TO WESTERLY LOW-LEVEL
FLOW SCOURS OUT THE FOG AND STRATUS. CONFIDENCE IS FAIRLY HIGH
THAT VISIBILITY WILL START TO IMPROVE BEFORE CEILING DOES...BUT
NEARLY ALL MODELS/GUIDANCE STRONGLY SUGGEST A RETURN TO OUTRIGHT-
VFR CONDITIONS EVEN CEILING-WISE BY EARLY AFTERNOON. CONFIDENCE IN
THE TIMING DETAILS IS ADMITTEDLY A BIT SHAKY...AS IT COULD BE A
VERY GRADUAL IMPROVEMENT OVER TIME OR IT COULD BE A VERY ABRUPT
IMPROVEMENT...SO STAY TUNED FOR AMENDMENTS. AS FOR WIND...SURFACE
BREEZES THIS MORNING WILL REMAIN QUITE STEADY FROM THE SOUTH AND
EVENTUALLY TURN MORE SOUTHWESTERLY...WITH GUST POTENTIAL TO AROUND
20KT. AS A TROUGH AXIS/WEAK COLD FRONT PASSES THROUGH DURING THE
DAY...BREEZES WILL DIMINISH A BIT AND TURN MORE WEST-
NORTHWESTERLY. VERY LATE IN THE PERIOD...STEADIER/GUSTIER NORTH-
NORTHWEST WIND WILL ARRIVE BEHIND A STRONGER COLD FRONT. TOWARD
THE VERY END OF THE PERIOD ANOTHER ROUND OF MVFR/POSSIBLY IFR
CEILING COULD BE ON THE DOORSTEP FROM THE NORTH...BUT WILL ADDRESS
THIS IN NEXT ISSUANCE. OTHERWISE...THE ONLY OTHER ITEM OF
NOTE INVOLVES A 4-HOUR PERIOD OF LOW LEVEL WIND SHEAR (LLWS) THAT
HAS BEEN INTRODUCED FROM 11-15Z THIS MORNING AT KGRI TO ACCOUNT
FOR A GENERALLY 30-35KT BULK SHEAR DIFFERENCE BETWEEN THE SURFACE
AND ROUGHLY 1500 FT AGL...THANKS TO SOUTHWESTERLY WIND TOPPING OUT
AROUND 45KT AT THIS LEVEL. HAVE OMITTED THIS LLWS MENTION FROM
KEAR GIVEN THAT BULK SHEAR DIFFERENCE SHOULD BE LESS LIKELY TO
EXCEED 30KT FOR SEVERAL HOURS...BUT IT WILL STILL BE CLOSE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...PFANNKUCH
SHORT TERM...PFANNKUCH
LONG TERM...ROSSI
AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS HASTINGS NE
417 AM CST TUE FEB 10 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 417 AM CST TUE FEB 10 2015
BEFORE STATING ANOTHER WORD...WANT TO SAY THAT THE ONGOING DENSE
FOG ADVISORY FOR MOST OF THE NEBRASKA CWA IS STANDING ON
INCREASINGLY-SHAKY GROUND BASED ON IMPROVING TRENDS THE NEXT FEW
HOURS...AND AN EARLY CANCELLATION BEFORE 5AM NEWS TIME IS
PROBABLY A GOOD BET...AS ALTHOUGH LOCALIZED POCKETS OF DENSE FOG
MIGHT STILL EXIST...THEY ARE CERTAINLY NOT LOOKING WIDESPREAD
ENOUGH TO SUPPORT A FORMAL HEADLINE.
ALTHOUGH ANOTHER SOMEWHAT TRICKY SKY COVER/TEMPERATURE FORECAST IS
IN STORE TODAY...THE ONE GLARING DIFFERENCE BETWEEN NOW AND 24
HOURS AGO IS THAT THE LOW STRATUS/FOG SITUATION IS ON A
DIMINISHING/IMPROVING TREND INSTEAD OF A WORSENING ONE...AND THE
ENTIRE AREA IS EXPECTED TO WARM INTO THE 50S/60S TODAY INSTEAD OF
JUST WESTERN COUNTIES. RUNNING WITH THE ASSUMPTION THAT SKIES
OVER THE CWA SHOULD EXHIBIT A FAIRLY EFFICIENT WEST-TO-EAST AND
IN SOME AREAS A NORTH-TO-SOUTH CLEARING TREND THROUGH MID-
DAY...WE SHOULD NOT BE FACING THE PESKY EXTREMELY SHARP INTERFACE
BETWEEN CLOUDY/SUNNY AREAS THAT LINGERED ALL DAY YESTERDAY. THAT
BEING SAID...WITH EASTERN COUNTIES NEAREST HIGHWAY 81 EXPECTED TO
BE LAST TO SEE APPRECIABLE CLEARING...THESE AREAS SHOULD IN THEORY
REMAIN A BIT COOLER...AND ALSO STAND THE BEST POTENTIAL FOR A
MODEST TEMPERATURE BUST OF 5+ DEGREES.
PRECIPITATION-WISE...OTHER THAN ANY LINGERING LIGHT PATCHY DRIZZLE
OUT THERE THIS MORNING...THE VAST MAJORITY OF THE CWA IS EXPECTED
TO REMAIN DRY THROUGH THESE NEXT 24 HOURS AND THE OFFICIAL
FORECAST REMAINS AS SUCH. THAT BEING SAID...AT LEAST ONE RUN OF
THE NCEP 4KM WRF-NMM SUGGESTS THAT SOME ROGUE SPRINKLES/SPITS OF
DRIZZLE AND MAYBE EVEN A FEW FLURRIES CANNOT BE RULED OUT FROM
LATE THIS AFTERNOON INTO TONIGHT...BUT LACK OF CONFIDENCE IN
OCCURRENCE AND DOUBTS ABOUT HOW MUCH OF THIS LIGHT PRECIP WILL
ACTUALLY REACH THE GROUND HAS PRECLUDED ANY FORMAL FORECAST
MENTION AT THIS TIME. THIS WILL BE SOMETHING FOR THE NEXT FEW
SHIFTS TO KEEP AN EYE ON THOUGH.
ALTHOUGH IT IS EXPECTED TO ESSENTIALLY BE A DRY PASSAGE...THE COLD
FRONT PASSING THROUGH TONIGHT IS DECENTLY-STRONG AND WILL FEATURE
A NOTICEABLE INCREASE IN LATE-NIGHT NORTH WIND...AND SET THE STAGE
FOR A ROUGHLY A 20-DEGREE COOL DOWN FOR WEDNESDAY AS DESCRIBED IN
THE LONG TERM BELOW.
AS FOR THE HERE AND NOW AS OF 1030Z/430AM...ALTHOUGH THE VAST
MAJORITY OF THE CWA REMAINS SOCKED UNDER A VERY LOW STRATUS
DECK...SOME MODEST POCKETS OF CLEARING HAVE BEEN NOTED MAINLY IN
PARTS OF KS ZONES AND ALSO THE THAYER COUNTY AREA. MORE
IMPORTANTLY...INCREASING BOUNDARY-LAYER FLOW THAT IS STARTING TO
TURN MORE SOUTHWESTERLY HAS RESULTED IN IMPROVING VISIBILITY
OVERNIGHT. AS OF THIS WRITING...NEARLY ALL AUTOMATED AIRPORT SITES
IN THE CWA ARE REPORTING VISIBILITY OF NOW-WORSE-THAN ONE-HALF
MILE. ACTUAL SURFACE WIND IS AVERAGING SUSTAINED 10-15 MPH IN MOST
AREAS WITH SOME HIGHER GUSTS MAINLY IN NEB ZONES. EARLIER IN THE
NIGHT AN AREA OF MAINLY ELEVATED RADAR RETURNS BRUSHED ACROSS FAR
NORTHERN ZONES BUT IS CURRENTLY FOCUSED OUTSIDE THE AREA FROM
NORTHEAST NEB NORTHWARD. WOULD NOT BE SHOCKED IF A FEW SLEET
PELLETS/SNOW GRAINS FELL FROM THOSE RADAR ECHOES BUT ITS A NON-
ISSUE NOW. LOW TEMPERATURES THIS MORNING ARE ON TRACK TO BOTTOM
OUT BETWEEN 29-35 IN MOST AREAS. IN THE MID-UPPER LEVELS...WATER
VAPOR SATELLITE AND SHORT TERM MODEL DATA CONFIRM A LOW-AMPLITUDE
SHORTWAVE TRACKING EITHER SIDE OF THE NEB/SD BORDER...PROMOTING
THE LIGHT PRECIP TO THE NORTH. THE ASSOCIATED SURFACE LOW WITH
THAT SYSTEM IS AIDING THE TRANSITION TO MORE SOUTH-SOUTHWESTERLY
SURFACE FLOW THAN THE SOUTHEASTERLY THAT PREVAILED 6-12 HOURS AGO.
MEANWHILE FARTHER NORTH...A SOMEWHAT STRONGER MID LEVEL WAVE IS
SLIPPING EAST-SOUTHEAST OUT OF CANADA INTO ND...AND WILL BE THE
DRIVING FORCE BEHIND THE COLD FRONTAL PASSAGE TONIGHT.
LOOKING FORWARD-FORECAST-WISE IN MORE DETAIL AND STARTING WITH
THE DAYTIME HOURS...ALREADY TOUCHED ON IT ABOVE...BUT THE NUMBER 1
CHALLENGE IS TRYING TO PIN DOWN THE DISSIPATION OF LINGERING
MAINLY LIGHT FOG AND ESPECIALLY THE STILL-EXPANSIVE STRATUS DECK.
ALTHOUGH PRONE TO PLENTY OF SITE-SPECIFIC ERROR...HAVE INDICATED A
FAIRLY- STEADY MAINLY WEST-TO-EAST CLEARING TREND THROUGH MID-
DAY...WITH AT LEAST THE WESTERN 2/3 OF THE CWA LIKELY SEEING
PLENTY OF SUN BY NOON OR SO. THE LATEST HRRR LOW CLOUD PRODUCT
WOULD SUGGEST CLEARING COULD BE EVEN MORE RAPID BUT AM A TOUCH
SKEPTICAL OF THAT. COUNTIES NEAR/ALONG THE HIGHWAY 81 CORRIDOR ARE
MOST PRONE TO SEE AT LEAST HALFWAY-DECENT COVERAGE OF LOW CLOUDS
LINGER INTO EARLY AFTERNOON...BUT WHEN ALL IS SAID AND DONE WOULD
BE SURPRISED IF THE ENTIRE CWA DOES NOT CATCH AT LEAST A FEW HOURS
OF SUN TODAY AS LOW LEVEL FLOW CONTINUES TURNING
WESTERLY/NORTHWESTERLY AND HELPS TO ERODE THE LOW CLOUD MASS. AS A
WEAK TROUGH PASSES THROUGH THE AREA...A GRADUAL TRANSITION FROM
SOUTHERLY TO MORE WESTERLY AND EVENTUALLY NORTHWEST BREEZES WILL
OCCUR TODAY. WHILE SUSTAINED SPEEDS THROUGH MOST OF THE DAY SHOULD
ONLY AVERAGE NO MORE THAN 10-15 MPH WITH SLIGHTLY HIGHER GUSTS.
TEMP-WISE...GENERALLY FOLLOWED A BLEND OF SOME OF THE MOST
OPTIMISTIC MODELS TO YIELD UPPER 50S- MID 60S ACROSS THE MAJORITY
OF THE CWA...BUT HEDGED A BIT COOLER IN FAR EASTERN ZONES WITH
MAINLY MID-50S. OF COURSE...IF LOW STRATUS UNEXPECTEDLY HANGS
AROUND LONGER IN THIS AREA...THIS COULD BE A BIT OPTIMISTIC.
OVERALL THOUGH...UPPED HIGHS ONLY 1-2 DEGREES FROM PREVIOUS
FORECAST. AS EARLIER-STATED...ALTHOUGH NOT IN THE OFFICIAL
FORECAST...SUPPOSE A FEW LATE-DAY SPRINKLES CANNOT BE RULED OUT
MAINLY NORTH OF I-80.
TURNING TO THIS EVENING TONIGHT...THE AFOREMENTIONED DAKOTAS
DISTURBANCE WILL TRACK INTO THE GREAT LAKES REGION...AND BE
REINFORCED BY ANOTHER LOBE OF ENERGY DROPPING SOUTHWARD TOWARD
MN/ND OUT OF CANADA. AGAIN...ALTHOUGH SOME VERY LIGHT/SPOTTY
PRECIP CANNOT BE RULED OUT TONIGHT LOCALLY...BY FAR THE MAIN STORY
WILL BE THE PASSAGE OF A FAIRLY HEALTHY COLD FRONT...WITH 850
MILLIBAR TEMPS BY SUNRISE WEDNESDAY PROGGED TO GENERALLY DROP INTO
THE -3 TO -8 C RANGE OVER MOST OF THE CWA. ALTHOUGH NOT OVERLY-
WINDY...THE ARRIVAL OF THIS FRONT WILL BE MARKED BY SEVERAL HOURS
OF SUSTAINED 15-25 MPH NORTH WIND WITH GUSTS UP TO AROUND 30 MPH.
EXCEPT GENERALLY NORTH OF I-80...THE BRUNT OF THESE STRONGER WINDS
WILL NOT KICK IN UNTIL NEAR/AFTER MIDNIGHT. ALTHOUGH NOT
NECESSARILY EXPECTING ANOTHER TOTALLY-SOLID LOW STRATUS DECK
MOVING IN BEHIND THE FRONT...MODELS SUGGEST A COMBINATION OF
PARTLY- MOSTLY CLOUDY SKIES OVERNIGHT BEHIND THE BOUNDARY...WITH
ANY LOWER STRATUS THAT IS PRESENT POSSIBLY EVEN TRYING TO THROW
OUT A FEW SPITS OF DRIZZLE. AGAIN THOUGH...CONFIDENCE JUST TOO LOW
TO "RUIN" THE CURRENTLY DRY FORECAST. TEMP-WISE...LOWS WILL BE A
LITTLE TRICKY AS WELL...AS FAIRLY PRONOUNCED LOW LEVEL COLD AIR
ADVECTION WILL USHER IN COLDER AIR...BUT ITS FULL POTENTIAL MAY BE
MITIGATED A BIT BY THE INFLUENCE OF LOW LEVEL MIXING FROM THE
STEADY WIND AND ALSO CLOUD COVER. BLENDED A FEW MODELS TOGETHER TO
ESSENTIALLY DROP LOWS A FEW DEGREES IN THE NORTH AND BRING THEM UP
VERY SLIGHTLY SOUTH...AIMING FOR A RANGE FROM MID-20S NORTH OF
I-80 TO MID-30S IN KS ZONES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 417 AM CST TUE FEB 10 2015
FLUCTUATING TEMPERATURES AND MOSTLY DRY CONDITIONS WILL CONTINUE
THROUGH THE EXTENDED PERIODS...WITH ONLY A SMALL CHANCE OF SOME
LIGHT SNOW RETURNING NEXT MONDAY OR TUESDAY.
OVERALL...EXPECT NORTHWESTERLY FLOW ALOFT TO BE DOMINANT THROUGH THE
EXTENDED PERIODS AS A RIDGE OF HIGH PRESSURE BUILDS ACROSS THE WEST
COAST AND MULTIPLE LOW PRESSURE SYSTEMS SWING THROUGH THE OHIO RIVER
VALLEY AND UP THE EAST COAST. THIS GENERAL PATTERN IS FORECAST TO
HOLD THROUGH MOST OF THE EXTENDED...WITH AN UPPER LEVEL DISTURBANCE
PUSHING ACROSS BRITISH COLUMBIA ON SUNDAY FORECAST TO DROP INTO THE
PLAINS EARLY NEXT WEEK. WHILE NOT OVERLY MOIST...THIS SYSTEM WILL
BRING THE BEST CHANCE FOR SOME LIGHT SNOWFALL TO THE LOCAL AREA IN
OVER A WEEK.
STARTING OFF WEDNESDAY...EXPECT BREEZY NORTHERLY WINDS TO BE
ADVECTING COOLER AIR FROM THE NORTH THROUGH THE DAY BEHIND AN EARLY
MORNING COLD FRONT. WHILE NOT BITTERLY COLD...THIS AIRMASS WILL BE
IN STARK CONTRAST TO THIS AFTERNOONS ABOVE NORMAL TEMPERATURES....
LIKELY DROPPING AFTERNOON READINGS VERY CLOSE TO CLIMATOLOGY FOR MID
FEBRUARY. WITH THE ASSOCIATED SURFACE HIGH SLIDING SOUTHEAST ACROSS
THE MISSOURI RIVER VALLEY TO START THE DAY ON THURSDAY...EXPECT A
RETURN TO BELOW NORMAL TEMPERATURES TO START THE DAY...WITH SINGLE
DIGITS FORECAST FOR AT LEAST THE NORTHEASTERN HALF OF THE LOCAL AREA
WHERE THE WINDS WILL BE THE LIGHTEST. WHILE THESE COOL MORNING TEMPS
APPEAR TO BE A SURE THING...AFTERNOON TEMPS ARE A BIT TRICKIER AS
THERE COULD BE A SHARP GRADIENT ACROSS THE LOCAL AREA AS WINDS MAY
BEGIN TO SHIFT LATE IN THE DAY IN RESPONSE TO A SURFACE TROUGH
TRACKING EASTWARD FROM COLORADO. THAT SAID...MODEL CONSENSUS KEEPS
THE WINDS GENERALLY SOUTHERLY BEHIND THE DEPARTING HIGH THROUGH THE
PERIOD OF MAXIMUM HEATING...SO KEPT TEMPS ON THE COOLER SIDE ACROSS
OUR LOCAL AREA THURSDAY AFTERNOON.
THEN AS THE SURFACE TROUGH MOVES ACROSS THE HEART OF THE LOCAL AREA
ON FRIDAY...TEMPERATURES SHOULD SHOOT BACK UP WELL ABOVE NORMAL TO
END THE WEEK...ONLY TO BE BROUGHT BACK DOWN OVER THE UPCOMING
WEEKEND AS A BACKDOOR COLD FRONT WORKS ITS WAY WEST...ASSOCIATED
WITH A VIGOROUS LOW PRESSURE SYSTEM ACROSS THE GREAT LAKES REGION.
WHILE THERE IS SOME DISCREPANCY WITH JUST HOW COLD THIS AIRMASS WILL
BE...TEMPERATURES SHOULD DROP OFF SIGNIFICANTLY...WITH BELOW NORMAL
TEMPERATURES FORECAST FOR SATURDAY...AND ONLY A MODEST WARM UP TO
END THE WEEKEND.
STARTING NEXT WEEK...THE FOCUS WILL SHIFT TO A WEST COAST SYSTEM
THAT WILL BRING ANOTHER COLD FRONT ACROSS THE LOCAL AREA LATE MONDAY
OR TUESDAY...BRINGING ENOUGH MOISTURE TO JUSTIFY THE MENTION FOR A
SMALL CHANCE FOR SOME LIGHT SNOWFALL FOR THE TIME BEING.
OVERALL...THIS DOES NOT APPEAR TO BE A VERY MOIST SYSTEM...BUT WITH
VERY COLD TEMPERATURES...WE COULD SEE SOME LIGHT ACCUMULATIONS AS A
RESULT OF HIGH SNOWFALL RATIOS IF MODEL TRENDS HOLD.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1214 AM CST TUE FEB 10 2015
ALTHOUGH SEVERAL MORE HOURS OF VERY POOR (MAINLY LIFR)
CEILING/VISIBILITY CONDITIONS ARE EXPECTED AT BOTH TERMINALS
THROUGH THESE FIRST SEVERAL HOURS THIS MORNING IN PERSISTENT
FOG/STRATUS/LIGHT DRIZZLE...A MARKED IMPROVEMENT IS EXPECTED FOR
BY THE LATTER HALF OF THE PERIOD AS A RETURN TO WESTERLY LOW-LEVEL
FLOW SCOURS OUT THE FOG AND STRATUS. CONFIDENCE IS FAIRLY HIGH
THAT VISIBILITY WILL START TO IMPROVE BEFORE CEILING DOES...BUT
NEARLY ALL MODELS/GUIDANCE STRONGLY SUGGEST A RETURN TO OUTRIGHT-
VFR CONDITIONS EVEN CEILING-WISE BY EARLY AFTERNOON. CONFIDENCE IN
THE TIMING DETAILS IS ADMITTEDLY A BIT SHAKY...AS IT COULD BE A
VERY GRADUAL IMPROVEMENT OVER TIME OR IT COULD BE A VERY ABRUPT
IMPROVEMENT...SO STAY TUNED FOR AMENDMENTS. AS FOR WIND...SURFACE
BREEZES THIS MORNING WILL REMAIN QUITE STEADY FROM THE SOUTH AND
EVENTUALLY TURN MORE SOUTHWESTERLY...WITH GUST POTENTIAL TO AROUND
20KT. AS A TROUGH AXIS/WEAK COLD FRONT PASSES THROUGH DURING THE
DAY...BREEZES WILL DIMINISH A BIT AND TURN MORE WEST-
NORTHWESTERLY. VERY LATE IN THE PERIOD...STEADIER/GUSTIER NORTH-
NORTHWEST WIND WILL ARRIVE BEHIND A STRONGER COLD FRONT. TOWARD
THE VERY END OF THE PERIOD ANOTHER ROUND OF MVFR/POSSIBLY IFR
CEILING COULD BE ON THE DOORSTEP FROM THE NORTH...BUT WILL ADDRESS
THIS IN NEXT ISSUANCE. OTHERWISE...THE ONLY OTHER ITEM OF
NOTE INVOLVES A 4-HOUR PERIOD OF LOW LEVEL WIND SHEAR (LLWS) THAT
HAS BEEN INTRODUCED FROM 11-15Z THIS MORNING AT KGRI TO ACCOUNT
FOR A GENERALLY 30-35KT BULK SHEAR DIFFERENCE BETWEEN THE SURFACE
AND ROUGHLY 1500 FT AGL...THANKS TO SOUTHWESTERLY WIND TOPPING OUT
AROUND 45KT AT THIS LEVEL. HAVE OMITTED THIS LLWS MENTION FROM
KEAR GIVEN THAT BULK SHEAR DIFFERENCE SHOULD BE LESS LIKELY TO
EXCEED 30KT FOR SEVERAL HOURS...BUT IT WILL STILL BE CLOSE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR NEZ039>041-
046>049-061>064-073>077-083>087.
KS...NONE.
&&
$$
SHORT TERM...PFANNKUCH
LONG TERM...ROSSI
AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
932 AM EST TUE FEB 10 2015
.SYNOPSIS...
HIGH PRESSURE BUILDING EASTWARD FROM THE GREAT LAKES AND NORTHERN
ONTARIO WILL PROVIDE DRY AND SEASONABLY COLD WEATHER WEATHER
CONDITIONS ACROSS THE NORTH COUNTRY TODAY THROUGH WEDNESDAY.
PREVAILING LOW CLOUDS WILL GRADUALLY DIMINISH PROVIDING PARTLY
CLOUDY CONDITIONS THIS AFTERNOON THROUGH MUCH OF WEDNESDAY. AN
ALBERTA CLIPPER WILL MOVE EAST SOUTHEASTWARD INTO OUR REGION DURING
THE PRE-DAWN HOURS THURSDAY...WITH PERIODS OF LIGHT SNOW CONTINUING
THROUGHOUT THE DAYLIGHT HOURS THURSDAY INTO EARLY THURSDAY NIGHT.
SOME MINOR TRAVEL IMPACTS ARE POSSIBLE WITH WIDESPREAD LIGHT SNOW
ACCUMULATIONS EXPECTED. NO SIGNIFICANT PRECIPITATION SYSTEMS ARE
EXPECTED THEREAFTER...BUT BITTERLY COLD AIR WILL BECOME ESTABLISHED
ACROSS THE REGION FRIDAY AND CONTINUING INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 924 AM EST TUESDAY...WIDESPREAD DECK OF STRATUS REMAINS
TRAPPED UNDER THE DEVELOPING SUBSIDENCE INVERSION. EVEN SEEING
SOME REPORTS OF FLURRIES ACROSS NORTHERN NEW YORK AND VERMONT.
BACK EDGE OF CLOUDS IS NOW NEAR OTTAWA AND MOVING SLOWLY BUT
SURELY FROM NORTHWEST TO SOUTHEAST AS DRIER AIR OVER SOUTHERN
CANADA GRADUALLY PUSHES SOUTHWARD. RAP LOW LEVEL MOISTURE FIELDS
APPEAR TO HANDLING IT THE BEST AND LARGELY USED ITS DEPICTION FOR
CLOUD TRENDS. THUS EXPECTING CLOUD SHIELD TO GRADUALLY ERODE AND
PUSH SOUTH AND EAST AS WE HEAD INTO THE AFTERNOON HOURS. THINKING
CLEARING SKIES REACH THE SAINT LAWRENCE VALLEY AND NORTHERN
CHAMPLAIN VALLEY AROUND 1 PM...BURLINGTON AREA AROUND 2
PM...CENTRAL VERMONT 3 PM...AND FINALLY SOUTHERN VERMONT BY 4 PM.
HIGH TEMPERATURES SHOULD STILL REACH THE 20S FOR THE MOST...EXCEPT
SOME UPPER TEENS ACROSS PARTS OF NORTHERN NEW YORK.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
AS OF 321 AM EST TUESDAY...SURFACE RIDGE AXIS BUILDS ACROSS
QUEBEC AND NORTHERN NEW ENGLAND OVERNIGHT TONIGHT. PROVIDED SKIES
BECOME MOSTLY CLEAR AS EXPECTED...SHOULD SET UP A GOOD RADIATIVE
COOLING SETUP WITH LIGHT WINDS AND FRESH SNOW COVER. LOOKING AT
LOWS GENERALLY -8 TO +2F (WARMEST IN THE CHAMPLAIN VALLEY AND FAR
SERN VT)...BUT COULD SEE SOME READINGS IN THE TEENS BELOW ZERO
AROUND KSLK AND THE COLDER HOLLOWS IN VERMONT/S NORTHEAST KINGDOM.
POPS NIL.
SURFACE RIDGE AXIS SHOULD HOLD IN PLACE THROUGHOUT THE DAY
WEDNESDAY FROM MAINE SWWD THROUGH VT/NH AND INTO SERN NY.
MEANWHILE...ALBERTA CLIPPER LOW AND ASSOCIATED MID- LEVEL TROUGH
WILL BE SHIFTING ESEWD ACROSS THE GREAT LAKES REGION BY WEDNESDAY
AFTERNOON. DEVELOPING MID- LEVEL SWLY FLOW IN ADVANCE OF THE
TROUGH AXIS SHOULD YIELD AN INCREASE IN MID TO UPPER CLOUDINESS
FROM W-E ACROSS THE NORTH COUNTRY AS THE DAY PROGRESSES. SFC WINDS
SHOULD REMAIN LIGHT AND NOT EXPECTING ANY PRECIPITATION WITH VERY
DRY PBL CONDITIONS PREVAILING. HIGH TEMPERATURES SHOULD REACH THE
15-20F RANGE IN MOST LOCATIONS.
IT APPEARS THAT AREAS OF LIGHT SNOW WILL DEVELOP EASTWARD ACROSS THE
NORTH COUNTRY IN ASSOCIATED WITH THE CLIPPER SYSTEM DURING WEDNESDAY
NIGHT. SHOULD SEE SNOW BEGIN AROUND MIDNIGHT IN NRN NY AND DURING
THE PRE-DAWN HOURS FOR VERMONT. PRIMARY LOW SHIFTS SLOWLY EASTWARD
ACROSS THE REGION LATE THURSDAY MORNING INTO THURSDAY
AFTERNOON...WITH CONTINUED OVERCAST SKIES AND PERIODS OF LIGHT SNOW.
PRESENT INDICATES FROM 00Z GFS/NAM SUGGEST QPF VALUES OF 0.15 TO
0.3". GIVEN POTENTIAL FOR GOOD DENDRITE GROWTH PER MODEL
SOUNDINGS...SLR/S AROUND 15:1 WOULD YIELD 2-5" WITH THIS SYSTEM OF
GENERALLY LOW DENSITY SNOWFALL. MAIN IMPACT WOULD BE TO
TRAVEL...WITH MINOR SLOWDOWNS EXPECTED FOR BOTH THE EARLY MORNING
AND EVENING COMMUTES ON THURSDAY.
LOW TEMPS WEDNESDAY NIGHT WILL NOT DROP VERY FAR WITH OVERCAST
CONDITIONS IN PLACE (GENERALLY LOW TO MID TEENS). LIKEWISE...HIGHS
THURSDAY WILL ONLY CLIMB INTO THE LOW 20S FOR MOST SECTIONS...WHICH
WILL PROBABLY BE OUR "WARMEST" DAY FOR A WHILE AS ARCTIC AIR RETURNS
IN THE WAKE OF THE CLIPPER SYSTEM BEGINNING FRIDAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 320 AM EST MONDAY...DAYS 4 THRU 7 WILL FEATURE DEEP FULL
LATITUDE TROF ACROSS THE EASTERN CONUS WITH SEVERAL COMPACTED
VORTICITIES MOVING ACROSS THE GREAT LAKE AND NE CONUS. THIS LARGE
SCALE SYNOPTIC SETUP WILL FEATURE TEMPS 10 TO 20 DEGREES BLW FOR
THE WEEKEND...AND MOSTLY A DRY FCST. MODEL TRENDS CONT TO SHOW THE
GFS SOLUTION AND ASSOCIATED ENSEMBLE MEMBERS AS THE MOST
AGGRESSIVE WITH S/W ENERGY AND DEVELOPMENT OF STRONG SFC LOW PRES
OFF THE SNE COAST ON FRIDAY...WITH SOME MOISTURE BEING ADVECTED
BACK INTO OUR CWA. HOWEVER...ECMWF IS FURTHER EAST WITH CYCLONE
DEVELOPMENT AND PLACES MUCH LESS DYNAMICS AND MOISTURE ACRS OUR
CWA. WL MENTION CHC POPS ACROSS THE SAINT LAWRENCE VALLEY TO
LIKELY FOR CHAMPLAIN VALLEY AND POINTS EASTWARD ON THURS NIGHT
INTO FRIDAY MORNING. HOWEVER...WITH PWS DROPPING BLW
0.25"...EXPECTING ONLY LIGHT SNOW ACCUMULATIONS...AN ADDITIONAL
DUSTING TO 2 INCHES. PROGGED 85H TEMPS DROP BTWN -22C AND -25C BY
12Z SATURDAY...WITH 925MB TEMPS BTWN -20C TO -24C...SUPPORTING
HIGHS MAINLY 0 TO 10F FOR BOTH FRIDAY AND SATURDAY WITH LOWS -5F
TO -15F. A WIND CHILL ADVISORY WILL BE LIKELY DURING THIS
PERIOD...GIVEN THE EXPECTED PRES GRADIENT ACROSS OUR
CWA...ASSOCIATED WITH DEVELOPING LOW PRESS OFF THE SNE COAST ON
FRIDAY.
NEXT TIGHTLY COMPACTED VORTEX DROPS FROM THE HUDSON BAY REGION ON
SAT INTO SUNDAY AND QUICKLY BECOMES CLOSED OFF AT 7H/5H WITH RAPID
SFC LOW PRES DEVELOPMENT OFF THE SNE COAST. THIS LOOKS TO DEVELOP
TOO FAR EAST TO HAVE SIGNIFICANT PRECIP IMPACTS ACRS OUR CWA...BUT
GUSTY NORTH TO NORTHWEST WINDS WILL RESULT IN STRONG LLVL CAA.
ONCE AGAIN GFS IS MORE AGGRESSIVE WITH ADVECTING LOW LEVEL COLD
AIR ACROSS OUR CWA WITH BOTH 925MB AND 850MB TEMPS NEAR -30C BY
12Z SUNDAY. MEANWHILE...LATEST 00Z EWCMF IS SLIGHTLY WARMER WITH
925MB TO 850MB TEMPS BTWN -24C AND -28C DURING THIS TIME PERIOD.
HAVE NOTED GFS ENSEMBLE 850MB TEMPS ARE 2 TO 3 STD BLW NORMAL
DURING THIS TIME PERIOD...WITH PW VALUES BTWN 1 AND 2 STD BLW
NORMAL...SUPPORTING A COLD AND MAINLY DRY FCST. GIVEN LOW LEVEL
THERMAL PROFILES HIGHS WILL STRUGGLE IN THE -5F TO +5F RANGE FOR
SUNDAY...WITH LOWS SUNDAY NIGHT/MONDAY MORNING BTWN -10F AND -20F.
ALSO...THE COMBINATION OF DEEPENING SFC LOW PRES OVER THE NORTH
ATLANTIC AND BUILDING HIGH PRES WILL CREATE A TIGHT PRES GRADIENT
OVER OUR CWA...WITH GUSTY NORTHWEST WINDS AT 15 TO 25 MPH EXPECTED
WITH THESE COLD TEMPS...CREATING BITTERLY COLD WIND CHILLS. WIND
CHILL ADVISORIES AND WARNINGS WILL BE LIKELY SAT NIGHT THRU
MONDAY. THE ONLY THINK FROM KEEPING TEMPS FROM DROPPING BTWN -20F
AND -30F BY MONDAY MORNING WITH BE THE BRISK WINDS AND SOME MID
LEVEL CLOUDS. THE COLDEST CORE OF AIR SLOWLY MODIFIES BY
MONDAY...WITH WEAK LOW LEVEL WARM ADVECTION DEVELOPING. PROGGED
85H TEMPS WARM TO -20C BY 18Z MONDAY...WITH SFC RIDGE OVERHEAD.
THIS WILL SUPPORT HIGHS BTWN ZERO AND +10F MOST LOCATIONS...WITH
ANOTHER VERY COLD NIGHT EXPECTED ON TUESDAY MORNING. ONCE
AGAIN...GFS AND ECMWF BOTH SHOW CLOUDS INCREASING FROM LOW LEVEL
WARM ADVECTION OVERNIGHT...WILL MAY PREVENT TEMPS FROM COMPLETELY
BOTTOMING OUT. WILL KEEP LOWS MAINLY -5F TO -15F...BUT IF MORE
CLEARING DEVELOPS THAN FORECAST LOWS WILL BE -10F TO -20F WITH
ISOLATED VALUES NEAR -30F...NEK AND SLK.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
THROUGH 12Z WEDNESDAY...LOW CLOUDS STILL HANGING TOUGH THIS
MORNING ACROSS ALL OUR TAF SITES WITH GENERAL VFR TO MVFR
CONDITIONS. HAVE NOTED IFR CIGS AT SLK. SOUNDINGS ARE TRICKY TODAY
WITH PLENTY OF LOW LEVEL MOISTURE BELOW TEMP INVERSION...ALONG
WITH WEAK FLOW AND LIMITED MIXING. THESE FACTORS COMBINED WITH
WEAK UPSLOPE FLOW...WILL RESULT IN IFR CIGS AT SLK THRU 16Z.
ELSEWHERE...EXPECTING MVFR CIGS TO SLOWLY BECOME VFR BTWN 15Z-17Z
TODAY...AND ALL SITES SHOULD HAVE VFR CONDITIONS BY 21Z THIS
EVENING. IN ADDITION...LOOK FOR A LIGHT NORTH TO NORTHWEST WIND AT
4 TO 8 KNOTS...TO BECOME LIGHT AND TRRN DRIVEN THIS EVENING.
OUTLOOK 12Z WEDNESDAY THROUGH FRIDAY... VFR CONDITIONS WITH
SURFACE HIGH PRESSURE THROUGH 00Z THURS. WEAK CLIPPER SYSTEM WILL
PRODUCE IFR CONDITIONS BETWEEN 03Z THURSDAY TO 18Z THURSDAY WITH
SURFACE VIS VALUES OF 1 TO 3SM AND MVFR CIGS. A BRIEF PERIOD OF
LIFR CONDITIONS WILL BE LIKELY ASSOCIATED WITH THE ACTUAL SFC COLD
FRONT. OTHERWISE...LINGERING SNOW SHOWERS WILL PERSIST INTO FRIDAY
WITH MAINLY MVFR VIS/CIGS IN THE MTNS AND TRENDING VFR ELSEWHERE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...MUCCILLI
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
736 AM EST TUE FEB 10 2015
.SYNOPSIS...
HIGH PRESSURE BUILDING EASTWARD FROM THE GREAT LAKES AND NORTHERN
ONTARIO WILL PROVIDE DRY AND SEASONABLY COLD WEATHER WEATHER
CONDITIONS ACROSS THE NORTH COUNTRY TODAY THROUGH WEDNESDAY.
PREVAILING LOW CLOUDS WILL GRADUALLY DIMINISH PROVIDING PARTLY
CLOUDY CONDITIONS THIS AFTERNOON THROUGH MUCH OF WEDNESDAY. AN
ALBERTA CLIPPER WILL MOVE EAST SOUTHEASTWARD INTO OUR REGION DURING
THE PRE-DAWN HOURS THURSDAY...WITH PERIODS OF LIGHT SNOW CONTINUING
THROUGHOUT THE DAYLIGHT HOURS THURSDAY INTO EARLY THURSDAY NIGHT.
SOME MINOR TRAVEL IMPACTS ARE POSSIBLE WITH WIDESPREAD LIGHT SNOW
ACCUMULATIONS EXPECTED. NO SIGNIFICANT PRECIPITATION SYSTEMS ARE
EXPECTED THEREAFTER...BUT BITTERLY COLD AIR WILL BECOME ESTABLISHED
ACROSS THE REGION FRIDAY AND CONTINUING INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 723 AM EST TUESDAY...WEAK WIND FIELDS FROM THE SURFACE
THROUGH 10 KFT AND MOIST, ISOTHERMAL VERTICAL PROFILES HAVE LEFT
A PREVAILING STRATUS LAYER ACROSS THE NORTH COUNTRY EARLY THIS
MORNING, EVEN AS LOW PRESSURE DEPARTS WELL EAST OF CAPE COD. IT
APPEARS THAT AS THE SURFACE ANTICYCLONE BUILDS EASTWARD FROM NRN
ONTARIO THAT A MODEST INCREASE IN LOW-LEVEL NORTHERLY FLOW AND
INCREASED MID-LEVEL SUBSIDENCE WILL GRADUALLY ALLOW STRATUS LAYER
TO BREAK UP DURING THE DAYLIGHT HOURS TODAY. THE RAP AND NAM
SUGGEST THIS WILL OCCUR AROUND/AFTER 16Z. THE NORTH WINDS AND
LIMITED VERTICAL MIXING WILL KEEP TEMPERATURES BELOW NORMAL THIS
AFTERNOON...WITH HIGHS GENERALLY EXPECTED IN THE LOWER TO MID 20S.
MAY SEE A FEW LINGERING FLURRIES EARLY THIS MORNING...MAINLY
ACROSS THE MOUNTAINS...BUT OTHERWISE LOOKING AT DRY CONDITIONS
TODAY AND TONIGHT.
SURFACE RIDGE AXIS BUILDS ACROSS QUEBEC AND NORTHERN NEW ENGLAND
OVERNIGHT TONIGHT. PROVIDED SKIES BECOME MOSTLY CLEAR AS
EXPECTED...SHOULD SET UP A GOOD RADIATIVE COOLING SETUP WITH LIGHT
WINDS AND FRESH SNOW COVER. LOOKING AT LOWS GENERALLY -8 TO +2F
(WARMEST IN THE CHAMPLAIN VALLEY AND FAR SERN VT)...BUT COULD SEE
SOME READINGS IN THE TEENS BELOW ZERO AROUND KSLK AND THE COLDER
HOLLOWS IN VERMONT/S NORTHEAST KINGDOM. POPS NIL.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 321 AM EST TUESDAY...SURFACE RIDGE AXIS SHOULD HOLD IN PLACE
THROUGHOUT THE DAY WEDNESDAY FROM MAINE SWWD THROUGH VT/NH AND
INTO SERN NY. MEANWHILE...ALBERTA CLIPPER LOW AND ASSOCIATED MID-
LEVEL TROUGH WILL BE SHIFTING ESEWD ACROSS THE GREAT LAKES REGION
BY WEDNESDAY AFTERNOON. DEVELOPING MID- LEVEL SWLY FLOW IN ADVANCE
OF THE TROUGH AXIS SHOULD YIELD AN INCREASE IN MID TO UPPER
CLOUDINESS FROM W-E ACROSS THE NORTH COUNTRY AS THE DAY
PROGRESSES. SFC WINDS SHOULD REMAIN LIGHT AND NOT EXPECTING ANY
PRECIPITATION WITH VERY DRY PBL CONDITIONS PREVAILING. HIGH
TEMPERATURES SHOULD REACH THE 15-20F RANGE IN MOST LOCATIONS.
IT APPEARS THAT AREAS OF LIGHT SNOW WILL DEVELOP EASTWARD ACROSS THE
NORTH COUNTRY IN ASSOCIATED WITH THE CLIPPER SYSTEM DURING WEDNESDAY
NIGHT. SHOULD SEE SNOW BEGIN AROUND MIDNIGHT IN NRN NY AND DURING
THE PRE-DAWN HOURS FOR VERMONT. PRIMARY LOW SHIFTS SLOWLY EASTWARD
ACROSS THE REGION LATE THURSDAY MORNING INTO THURSDAY
AFTERNOON...WITH CONTINUED OVERCAST SKIES AND PERIODS OF LIGHT SNOW.
PRESENT INDICATES FROM 00Z GFS/NAM SUGGEST QPF VALUES OF 0.15 TO
0.3". GIVEN POTENTIAL FOR GOOD DENDRITE GROWTH PER MODEL
SOUNDINGS...SLR/S AROUND 15:1 WOULD YIELD 2-5" WITH THIS SYSTEM OF
GENERALLY LOW DENSITY SNOWFALL. MAIN IMPACT WOULD BE TO
TRAVEL...WITH MINOR SLOWDOWNS EXPECTED FOR BOTH THE EARLY MORNING
AND EVENING COMMUTES ON THURSDAY.
LOW TEMPS WEDNESDAY NIGHT WILL NOT DROP VERY FAR WITH OVERCAST
CONDITIONS IN PLACE (GENERALLY LOW TO MID TEENS). LIKEWISE...HIGHS
THURSDAY WILL ONLY CLIMB INTO THE LOW 20S FOR MOST SECTIONS...WHICH
WILL PROBABLY BE OUR "WARMEST" DAY FOR A WHILE AS ARCTIC AIR RETURNS
IN THE WAKE OF THE CLIPPER SYSTEM BEGINNING FRIDAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 320 AM EST MONDAY...DAYS 4 THRU 7 WILL FEATURE DEEP FULL
LATITUDE TROF ACROSS THE EASTERN CONUS WITH SEVERAL COMPACTED
VORTICITIES MOVING ACROSS THE GREAT LAKE AND NE CONUS. THIS LARGE
SCALE SYNOPTIC SETUP WILL FEATURE TEMPS 10 TO 20 DEGREES BLW FOR
THE WEEKEND...AND MOSTLY A DRY FCST. MODEL TRENDS CONT TO SHOW THE
GFS SOLUTION AND ASSOCIATED ENSEMBLE MEMBERS AS THE MOST
AGGRESSIVE WITH S/W ENERGY AND DEVELOPMENT OF STRONG SFC LOW PRES
OFF THE SNE COAST ON FRIDAY...WITH SOME MOISTURE BEING ADVECTED
BACK INTO OUR CWA. HOWEVER...ECMWF IS FURTHER EAST WITH CYCLONE
DEVELOPMENT AND PLACES MUCH LESS DYNAMICS AND MOISTURE ACRS OUR
CWA. WL MENTION CHC POPS ACROSS THE SAINT LAWRENCE VALLEY TO
LIKELY FOR CHAMPLAIN VALLEY AND POINTS EASTWARD ON THURS NIGHT
INTO FRIDAY MORNING. HOWEVER...WITH PWS DROPPING BLW
0.25"...EXPECTING ONLY LIGHT SNOW ACCUMULATIONS...AN ADDITIONAL
DUSTING TO 2 INCHES. PROGGED 85H TEMPS DROP BTWN -22C AND -25C BY
12Z SATURDAY...WITH 925MB TEMPS BTWN -20C TO -24C...SUPPORTING
HIGHS MAINLY 0 TO 10F FOR BOTH FRIDAY AND SATURDAY WITH LOWS -5F
TO -15F. A WIND CHILL ADVISORY WILL BE LIKELY DURING THIS
PERIOD...GIVEN THE EXPECTED PRES GRADIENT ACROSS OUR
CWA...ASSOCIATED WITH DEVELOPING LOW PRESS OFF THE SNE COAST ON
FRIDAY.
NEXT TIGHTLY COMPACTED VORTEX DROPS FROM THE HUDSON BAY REGION ON
SAT INTO SUNDAY AND QUICKLY BECOMES CLOSED OFF AT 7H/5H WITH RAPID
SFC LOW PRES DEVELOPMENT OFF THE SNE COAST. THIS LOOKS TO DEVELOP
TOO FAR EAST TO HAVE SIGNIFICANT PRECIP IMPACTS ACRS OUR CWA...BUT
GUSTY NORTH TO NORTHWEST WINDS WILL RESULT IN STRONG LLVL CAA.
ONCE AGAIN GFS IS MORE AGGRESSIVE WITH ADVECTING LOW LEVEL COLD
AIR ACROSS OUR CWA WITH BOTH 925MB AND 850MB TEMPS NEAR -30C BY
12Z SUNDAY. MEANWHILE...LATEST 00Z EWCMF IS SLIGHTLY WARMER WITH
925MB TO 850MB TEMPS BTWN -24C AND -28C DURING THIS TIME PERIOD.
HAVE NOTED GFS ENSEMBLE 850MB TEMPS ARE 2 TO 3 STD BLW NORMAL
DURING THIS TIME PERIOD...WITH PW VALUES BTWN 1 AND 2 STD BLW
NORMAL...SUPPORTING A COLD AND MAINLY DRY FCST. GIVEN LOW LEVEL
THERMAL PROFILES HIGHS WILL STRUGGLE IN THE -5F TO +5F RANGE FOR
SUNDAY...WITH LOWS SUNDAY NIGHT/MONDAY MORNING BTWN -10F AND -20F.
ALSO...THE COMBINATION OF DEEPENING SFC LOW PRES OVER THE NORTH
ATLANTIC AND BUILDING HIGH PRES WILL CREATE A TIGHT PRES GRADIENT
OVER OUR CWA...WITH GUSTY NORTHWEST WINDS AT 15 TO 25 MPH EXPECTED
WITH THESE COLD TEMPS...CREATING BITTERLY COLD WIND CHILLS. WIND
CHILL ADVISORIES AND WARNINGS WILL BE LIKELY SAT NIGHT THRU
MONDAY. THE ONLY THINK FROM KEEPING TEMPS FROM DROPPING BTWN -20F
AND -30F BY MONDAY MORNING WITH BE THE BRISK WINDS AND SOME MID
LEVEL CLOUDS. THE COLDEST CORE OF AIR SLOWLY MODIFIES BY
MONDAY...WITH WEAK LOW LEVEL WARM ADVECTION DEVELOPING. PROGGED
85H TEMPS WARM TO -20C BY 18Z MONDAY...WITH SFC RIDGE OVERHEAD.
THIS WILL SUPPORT HIGHS BTWN ZERO AND +10F MOST LOCATIONS...WITH
ANOTHER VERY COLD NIGHT EXPECTED ON TUESDAY MORNING. ONCE
AGAIN...GFS AND ECMWF BOTH SHOW CLOUDS INCREASING FROM LOW LEVEL
WARM ADVECTION OVERNIGHT...WILL MAY PREVENT TEMPS FROM COMPLETELY
BOTTOMING OUT. WILL KEEP LOWS MAINLY -5F TO -15F...BUT IF MORE
CLEARING DEVELOPS THAN FORECAST LOWS WILL BE -10F TO -20F WITH
ISOLATED VALUES NEAR -30F...NEK AND SLK.
&&
.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
THROUGH 12Z WEDNESDAY...LOW CLOUDS STILL HANGING TOUGH THIS
MORNING ACROSS ALL OUR TAF SITES WITH GENERAL VFR TO MVFR
CONDITIONS. HAVE NOTED IFR CIGS AT SLK. SOUNDINGS ARE TRICKY TODAY
WITH PLENTY OF LOW LEVEL MOISTURE BELOW TEMP INVERSION...ALONG
WITH WEAK FLOW AND LIMITED MIXING. THESE FACTORS COMBINED WITH
WEAK UPSLOPE FLOW...WILL RESULT IN IFR CIGS AT SLK THRU 16Z.
ELSEWHERE...EXPECTING MVFR CIGS TO SLOWLY BECOME VFR BTWN 15Z-17Z
TODAY...AND ALL SITES SHOULD HAVE VFR CONDITIONS BY 21Z THIS
EVENING. IN ADDITION...LOOK FOR A LIGHT NORTH TO NORTHWEST WIND AT
4 TO 8 KNOTS...TO BECOME LIGHT AND TRRN DRIVEN THIS EVENING.
OUTLOOK 12Z WEDNESDAY THROUGH FRIDAY... VFR CONDITIONS WITH
SURFACE HIGH PRESSURE THROUGH 00Z THURS. WEAK CLIPPER SYSTEM WILL
PRODUCE IFR CONDITIONS BETWEEN 03Z THURSDAY TO 18Z THURSDAY WITH
SURFACE VIS VALUES OF 1 TO 3SM AND MVFR CIGS. A BRIEF PERIOD OF
LIFR CONDITIONS WILL BE LIKELY ASSOCIATED WITH THE ACTUAL SFC COLD
FRONT. OTHERWISE...LINGERING SNOW SHOWERS WILL PERSIST INTO FRIDAY
WITH MAINLY MVFR VIS/CIGS IN THE MTNS AND TRENDING VFR ELSEWHERE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
950 AM EST TUE FEB 10 2015
.SYNOPSIS...
LOW PRESSURE OVER THE SOUTH CAROLINAS WILL DRIFT EAST AND
OFFSHORE TODAY. HIGH PRESSURE WILL BUILD IN ON WEDNESDAY. AN
ARCTIC COLD FRONT MOVES THROUGH ON THURSDAY MORNING.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM EST TUESDAY...
RADAR TRENDS SHOW STEEP DECLINE IN RETURNS THIS MORNING WITH JUST
SOME SPOTTY LIGHT PRECIPITATION FOR SOUTHSIDE VA AND THE PIEDMONT.
THIS WILL BE GONE BY NOONTIME. LOW LEVEL TEMPERATURE PROFILE IS
COLD ENOUGH TO SUPPORT A FEW FLAKES AND HAVE RECEIVED A FEW
REPORTS INDICATING SUCH...BUT NOTHING OF ANY CONSEQUENCE IS
EXPECTED. FREEZING FOG SITUATION WEST OF THE BLUE RIDGE IS
IMPROVING AND CONDITIONS ARE NOT EXPECTED TO PERSIST PAST MID
MORNING. HAVE NOT RECEIVED ANY REPORTS OF SLICK TRAVEL SO LIKELY
JUST SOME RIME ICING IN THE TREES AND SUCH.
VISIBLE SATELLITE IMAGES SHOW A GOOD AMOUNT OF CLEARING IN THE
NORTH CAROLINA FOOTHILLS...AND EVEN SOME BREAKS FURTHER NORTH INTO
THE NRV AND ALLEGHANY HIGHLANDS. MODELS ARE FAIRLY AGGRESSIVE WITH
CLEARING THINGS OUT TODAY BUT AM NOT CURRENTLY WILLING TO BUY OFF
ON THIS IN ITS ENTIRETY. WILL GO WITH THE IDEA OF IMPROVING
CONDITIONS WORKING THEIR WAY UP EAST OF THE BLUE RIDGE AS SFC LOW
PULLS AWAY FROM THE AREA AND NWLY FLOW KEEPS ENOUGH UPSLOPE
ENHANCEMENT OF LOW LEVEL MOISTURE TO MAINTAIN SOME CLOUDINESS.
THIS WILL IMPACT TEMPERATURES AS MORE SUN MEANS MORE HEAT SO WILL
BUMP MAX VALUES UP A BIT FROM THE NC FOOTHILLS INTO THE PIEDMONT.
IF THE CLEARING IS INDEED AS PRONOUNCED AS MODELS CURRENTLY
ADVERTISE TEMPS WILL LIKELY WARM FURTHER AND WILL HAVE TO ADJUST
VALUES UP AGAIN EARLY THIS AFTERNOON.
PREVIOUS AFD...
MAIN 500 MB SHORT WAVE WAS TRACKING ACROSS NORTH CAROLINA WITH THE
ASSOCIATED SURFACE LOW OFF THE COAST OF SOUTH CAROLINA. MODELS HAVE
THE 500 MB LOW CUTTING OFF THIS MORNING THEN MOVING SLOWLY EAST. AT
THE SURFACE...THE LARGEST PRESSURE FALLS WERE OFF THE CAROLINA
COAST. BY LATE THIS MORNING THE LOW WILL BE WELL OFFSHORE.
WINDS BECOME LIGHT AND VARIABLE OVER THE MOUNTAINS TONIGHT AS A
RIDGE OF HIGH PRESSURE MOVES INTO THE AREA. EXPECTING SOME GUSTY
WINDS IN THE EAST THIS MORNING THEN WINDS WILL DIMINISH THIS
AFTERNOON AND OVERNIGHT. STAYED CLOSE TO BIAS CORRECTED GUIDANCE
FOR OVERNIGHT LOWS.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
AS OF 345 AM EST TUESDAY...
WILL START WEDNESDAY OFF WITH ZONAL WEST TO EAST WIND FLOW BECOMING
INCREASINGLY ESTABLISHED FOR THE CENTRAL APPALACHIANS...AS LOW
PRESSURE OFF THE ATLANTIC COAST MOVES AWAY...AND A DEEP UPPER LEVEL
TROUGH BEGINS TO DIG ACROSS THE GREAT LAKES FROM NORTHERN CANADA.
HIGH PRESSURE WILL ALREADY BE ESTABLISHED IN THE LOW LEVELS...MAKING
FOR MOSTLY CLEAR SKIES. ABUNDANT SUNSHINE AND DOWNSLOPE WINDFLOW
WILL COMBINE TO PUSH AFTERNOON TEMPERATURES INTO THE UPPER 40S TO
MID 50S AREAWIDE. CLOUD COVER WILL INCREASE DURING THE EVENING
HOWEVER AS THE UPPER LEVEL TROUGH CONTINUES ITS APPROACH...WITH AN
ASSOCIATED ARCTIC COLD FRONT MAKING ITS WAY TOWARD THE APPALACHIAN
CHAIN THROUGH THE NIGHT...TRIGGERING LIGHT SNOW SHOWERS ACROSS THE
WESTERN RIDGES TOWARD DAWN THURSDAY.
THE ARCTIC COLD FRONT WILL BEGIN ITS PASSAGE ACROSS OUR AREA
THURSDAY MORNING...ENTERING SOUTHEAST WEST VIRGINIA AND THE MOUNTAIN
EMPIRE AROUND SUNRISE...AND REACHING THE COASTAL PLAIN BY MID
AFTERNOON. HIGH TEMPERATURES FOR THURSDAY WILL OCCUR DURING THE
MORNING JUST AHEAD OF FRONTAL PASSAGE. THE AIR BEHIND THE FRONT IS
COLD ENOUGH THAT IT WILL OVERCOME NORMAL DAYTIME HEATING...AND
THEREFORE WE WILL SEE TEMPERATURES STEADILY DROP THROUGH THE
AFTERNOON. HIGHS WILL RANGE FROM AROUND THE FREEZING MARK WEST OF
INTERSTATE 77...TO THE MID AND UPPER 40S ACROSS THE SOUTHSIDE.
SNOW SHOWERS CAN BE EXPECTED ALONG THE WESTERN RIDGES DURING THE
AFTERNOON...HOWEVER WINDS WILL NOT TRULY SHIFT NORTHWESTERLY UNTIL
EARLY EVENING ACROSS THE MOUNTAINS...WHEN THE BASE OF THE UPPER
TROUGH PASSES OVERHEAD. THE NORTHWESTERLY WIND SHIFT WILL BE FROM
THE PERFECT DIRECTION TO DRAW MOISTURE FROM LAKE MICHIGAN THURSDAY
EVENING INTO EARLY FRIDAY MORNING...WHEN THE HIGHEST SNOWFALL
ACCUMULATIONS ARE EXPECTED. 850MB TEMPERATURES FALLING INTO THE -16C
TO -20C RANGE ALONG THE WESTERN RIDGES WILL SUPPORT SNOW TO LIQUID
RATIOS IN THE 20:1 TO 25:1 RANGE. IN ADDITION...STRONG WINDS AND
UNIDIRECTIONAL FLOW MAY SUPPORT SNOW STREAMERS...WHERE NARROW BANDS
OF LOCALIZED HEAVY SNOW MAY OCCUR...POSSIBLY REACHING INTO THE NEW
RIVER VALLEY. WIND GUSTS OF 45 TO 50 MPH WILL BE COMMON ALONG THE
HIGHER RIDGES DURING THE EVENING...WELL INTO WIND ADVISORY CRITERIA.
BY SUNRISE FRIDAY...TEMPERATURES WILL HAVE FALLEN INTO THE POSITIVE
SINGLE DIGITS ACROSS THE MOUNTAINS...AND INTO THE LOW TO MID TEENS
ACROSS THE PIEDMONT. THESE COLD TEMPERATURES...WHEN FACTORING IN THE
STRONG WINDS...WILL CAUSE WIND CHILLS TO RANGE FROM NEAR ZERO ACROSS
THE SOUTHSIDE...TO THE NEGATIVE TEENS WEST OF THE BLUE RIDGE...
POSSIBLY AS LOW AS -30F IN A FEW SPOTS ALONG THE INTERSTATE 64
CORRIDOR. WIND SPEEDS WILL DECREASE HEADING INTO FRIDAY AFTERNOON...
ALLOWING WIND CHILLS TO RISE ABOVE ZERO MOST LOCATIONS. WINDS WILL
SHIFT MORE WESTERLY LATE IN THE DAY...WITH CLOUD COVER DECREASING...
WHICH WILL HELP AFTERNOON TEMPERATURES REBOUND INTO THE LOW 20S WEST
AND THE LOW 30S EAST. FRIDAY NIGHT TEMPERATURES WILL NOT BE AS
CHILLY...HOLDING IN THE TEENS MOST LOCATIONS.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 300 PM EST MONDAY...
BOTH THE GFS AND ECMWF KEEP NORTHWEST FLOW WITH A TROUGH/LOW NEAR
JAMES BAY AND RIDGING OVER THE WESTERN U.S. THROUGH SUNDAY.
A SHORTWAVE TROUGH IS FORECASTED TO ROTATE AROUND THE LONGWAVE
PATTERN THROUGH THE GREAT LAKES REGION AND INTO NEW ENGLAND.
THE SOUTHERN EXTENT OF THE ENERGY AND MOISTURE WITH THIS FEATURE IS
SLIGHTLY DIFFERENT DEPENDING ON MODEL CHOICE. STILL LEANING TOWARDS
THE DRIER AND LESS AMPLIFIED SOLUTION WITH RICHER MOISTURE NORTH OF
THE AREA. PLACED ISOLATED TO SCATTERED POPS IN THE WEST WITH THE
BEST CHANCES IN THE NORTHWEST FOR SATURDAY INTO SATURDAY NIGHT.
WINDS INCREASE SATURDAY INTO SATURDAY NIGHT WITH HEALTHY 4 TO 8 MB 6
HOUR PRESSURE RISES. HIGHS ON SATURDAY WILL VARY FROM THE LOWER 20S
IN THE NORTHWEST MOUNTAINS TO THE LOWER 40S IN THE PIEDMONTS.
THE COMBINATION OF WINDS AND TEMPERATURES WILL PRODUCE WIND CHILLS
BELOW ZERO AT THE HIGHER ELEVATIONS SATURDAY NIGHT INTO SUNDAY
MORNING. ACTUAL LOW TEMPERATURES SATURDAY WILL DROP INTO SINGLE
DIGITS TO MID TEENS. HIGH PRESSURE WILL SLOWLY SLIDE EAST SUNDAY
INTO SUNDAY NIGHT. HIGHS SUNDAY WILL VARY FRO THE MID TEENS IN THE
NORTHWEST TO LOWER 30S IN THE SOUTHEAST. ANOTHER COLD SUNDAY NIGHT
WITH LOW TEMPERATURES GENERALLY FROM THE SINGLE DIGITS AND TEENS.
THE HIGH CENTER MOVES SOUTHEAST ON MONDAY AND UPPER FLOW FLATTENS.
THE HIGH CENTER PUSHES OFF INTO THE ATLANTIC OCEAN MONDAY NIGHT INTO
TUESDAY. A COLD FRONT APPROACHES FROM THE WEST ON TUESDAY.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
AS OF 705 AM EST TUESDAY...
THERE WAS IFR FOG AND FREEZING FOG ALONG THE WEST SLOPES OF THE
APPALACHIANS EARLY THIS MORNING. MODELS WERE SUGGESTING LITTLE
IMPROVEMENT IN THE IFR CONDITIONS AT KBLF BEFORE NOON.
WESTERN EDGE OF A LARGE SHIELD OF PRECIPITATION EXTENDED FROM
KLYH TO KMTV THIS MORNING WITH WIDESPREAD MVFR CEILINGS AND
VISIBILITIES WITHIN THE PRECIPITATION...INCLUDING AT KLYH AND
KDAN. GETTING A FEW REPORTS OF SNOW MIXING IN WITH THE FAR
WESTERN EDGE OF THE PRECIPITATION.
EXPECTING THE RAIN TO END AT KLYH AND KDAN BY 17Z/NOON BASED ON
THE HRRR AND LOCAL WRF MODELS. BUT LOW CONFIDENCE ON THE TIMING
OF CEILINGS AND VISIBILITIES TODAY. THE EARLIEST THERE MAY BE ANY
VFR CEILINGS IS 20Z/3PM. AS LOW PRESSURE DEEPENS OFF THE COAST
TODAY...ENOUGH OF A PRESSURE GRADIENT FOR WIND GUSTS AROUND 20
KNOTS AT KLYH AND KDAN.
HIGH PRESSURE BUILDS IN OVER THE MOUNTAINS TONIGHT RESULTING IN
LIGHT AND VARIABLE WINDS. HAVE ADDED IFR FOG AND CEILINGS IN AT
KBLF AND KLWB OVERNIGHT WITH MEDIUM CONFIDENCE OF FOG FORMATION.
EXTENDED AVIATION DISCUSSION...
HIGH PRESSURE AND COLDER AIR WILL BUILD IN BEHIND THE COLD FRONT
WITH VFR FOR WEDNESDAY.
UPSLOPE SNOW SHOWERS ARE EXPECTED IN THE MOUNTAINS ON WEDNESDAY
NIGHT AND THURSDAY ALONG WITH A SHARP DROP IN TEMPERATURES
THURSDAY AND THURSDAY NIGHT BEHIND AN ARCTIC COLD FRONT. WIND
GUSTS BEHIND THE FRONT ON THURSDAY NIGHT MAY REACH 40-50 KNOTS IN
THE HIGHER ELEVATIONS.
HIGH PRESSURE BUILDS IN ALLOWING FOR DIMINISHING WINDS ON FRIDAY
WITH SOME LINGERING MVFR CIGS POSSIBLE OVER THE SOUTHEAST WEST VA
LOCATIONS.
ANOTHER FAST MOVING ARCTIC FRONT ARRIVES SATURDAY WITH A
RESUMPTION OF UPSLOPE SNOW SHOWERS INCLUDING MVFR CIGS/VSBYS ALONG
WITH INCREASING NORTHWEST WINDS THAT COULD AGAIN GUST TO 50 KNOTS
BY LATE IN THE DAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...MBS/AMS
SHORT TERM...NF
LONG TERM...KK
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
709 AM EST TUE FEB 10 2015
.SYNOPSIS...
LOW PRESSURE OVER THE SOUTH CAROLINAS WILL DRIFT EAST AND
OFFSHORE TODAY. HIGH PRESSURE WILL BUILD IN ON WEDNESDAY. AN
ARCTIC COLD FRONT MOVES THROUGH ON THURSDAY MORNING.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 400 AM EST TUESDAY...
MAIN 500 MB SHORT WAVE WAS TRACKING ACROSS NORTH CAROLINA WITH THE
ASSOCIATED SURFACE LOW OFF THE COAST OF SOUTH CAROLINA. MODELS HAVE
THE 500 MB LOW CUTTING OFF THIS MORNING THEN MOVING SLOWLY EAST. AT
THE SURFACE...THE LARGEST PRESSURE FALLS WERE OFF THE CAROLINA
COAST. BY LATE THIS MORNING THE LOW WILL BE WELL OFFSHORE.
WESTERN EDGE OF THE PRECIPITATION EXTENDED FROM LEXINGTON TO
HILLSVILLE AT 400 AM. THE PRECIPITATION WILL GRADUALLY END FROM WEST
TO EAST TODAY. LOCAL WRF AND HRRR MODELS SHOWED BACK EDGE EXITING
THE FAR EASTERN COUNTY WARNING AREA AROUND 1PM. THERE MAY BE SOME
CLEARING LATE IN THE DAY IN THE SOUTHERN FOOTHILLS BUT OVERALL CLOUD
COVER AND PRECIPITATION WILL HOLD TEMPERATURES DOWN. HAVE LEANED
TOWARD COOLER LAV GUIDANCE FOR MAXIMUM TEMPERATURES TODAY.
TEMPERATURES AND DEW POINTS WERE DROPPING THIS MORNING FROM BOTH THE
NORTH AND THE WEST. MESONET DATA SHOWED SOME TEMPERATURES AROUND
FREEZING ALONG THE BLUE RIDGE IN ROCKBRIDGE COUNTY...IN TAZEWELL
COUNTY AND IN THE HIGHER ELEVATIONS OF WATAUGA COUNTY. THESE HIGHER
ELEVATIONS WILL BE IN THE CLOUDS THIS MORNING SO SOME FREEZING FOG
IS POSSIBLE. VERY LIGHT ICING IN POSSIBLE ALONG THE BLUE RIDGE
BETWEEN ROCKBRIDGE AND AMHERST COUNTIES ON THE EXTREME WESTERN EDGE
OF THE PRECIPITATION SHIELD.
WINDS BECOME LIGHT AND VARIABLE OVER THE MOUNTAINS TONIGHT AS A
RIDGE OF HIGH PRESSURE MOVES INTO THE AREA. EXPECTING SOME GUSTY
WINDS IN THE EAST THIS MORNING THEN WINDS WILL DIMINISH THIS
AFTERNOON AND OVERNIGHT. STAYED CLOSE TO BIAS CORRECTED GUIDANCE FOR
OVERNIGHT LOWS.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
AS OF 345 AM EST TUESDAY...
WILL START WEDNESDAY OFF WITH ZONAL WEST TO EAST WIND FLOW BECOMING
INCREASINGLY ESTABLISHED FOR THE CENTRAL APPALACHIANS...AS LOW
PRESSURE OFF THE ATLANTIC COAST MOVES AWAY...AND A DEEP UPPER LEVEL
TROUGH BEGINS TO DIG ACROSS THE GREAT LAKES FROM NORTHERN CANADA.
HIGH PRESSURE WILL ALREADY BE ESTABLISHED IN THE LOW LEVELS...MAKING
FOR MOSTLY CLEAR SKIES. ABUNDANT SUNSHINE AND DOWNSLOPE WINDFLOW
WILL COMBINE TO PUSH AFTERNOON TEMPERATURES INTO THE UPPER 40S TO
MID 50S AREAWIDE. CLOUD COVER WILL INCREASE DURING THE EVENING
HOWEVER AS THE UPPER LEVEL TROUGH CONTINUES ITS APPROACH...WITH AN
ASSOCIATED ARCTIC COLD FRONT MAKING ITS WAY TOWARD THE APPALACHIAN
CHAIN THROUGH THE NIGHT...TRIGGERING LIGHT SNOW SHOWERS ACROSS THE
WESTERN RIDGES TOWARD DAWN THURSDAY.
THE ARCTIC COLD FRONT WILL BEGIN ITS PASSAGE ACROSS OUR AREA
THURSDAY MORNING...ENTERING SOUTHEAST WEST VIRGINIA AND THE MOUNTAIN
EMPIRE AROUND SUNRISE...AND REACHING THE COASTAL PLAIN BY MID
AFTERNOON. HIGH TEMPERATURES FOR THURSDAY WILL OCCUR DURING THE
MORNING JUST AHEAD OF FRONTAL PASSAGE. THE AIR BEHIND THE FRONT IS
COLD ENOUGH THAT IT WILL OVERCOME NORMAL DAYTIME HEATING...AND
THEREFORE WE WILL SEE TEMPERATURES STEADILY DROP THROUGH THE
AFTERNOON. HIGHS WILL RANGE FROM AROUND THE FREEZING MARK WEST OF
INTERSTATE 77...TO THE MID AND UPPER 40S ACROSS THE SOUTHSIDE.
SNOW SHOWERS CAN BE EXPECTED ALONG THE WESTERN RIDGES DURING THE
AFTERNOON...HOWEVER WINDS WILL NOT TRULY SHIFT NORTHWESTERLY UNTIL
EARLY EVENING ACROSS THE MOUNTAINS...WHEN THE BASE OF THE UPPER
TROUGH PASSES OVERHEAD. THE NORTHWESTERLY WIND SHIFT WILL BE FROM
THE PERFECT DIRECTION TO DRAW MOISTURE FROM LAKE MICHIGAN THURSDAY
EVENING INTO EARLY FRIDAY MORNING...WHEN THE HIGHEST SNOWFALL
ACCUMULATIONS ARE EXPECTED. 850MB TEMPERATURES FALLING INTO THE -16C
TO -20C RANGE ALONG THE WESTERN RIDGES WILL SUPPORT SNOW TO LIQUID
RATIOS IN THE 20:1 TO 25:1 RANGE. IN ADDITION...STRONG WINDS AND
UNIDIRECTIONAL FLOW MAY SUPPORT SNOW STREAMERS...WHERE NARROW BANDS
OF LOCALIZED HEAVY SNOW MAY OCCUR...POSSIBLY REACHING INTO THE NEW
RIVER VALLEY. WIND GUSTS OF 45 TO 50 MPH WILL BE COMMON ALONG THE
HIGHER RIDGES DURING THE EVENING...WELL INTO WIND ADVISORY CRITERIA.
BY SUNRISE FRIDAY...TEMPERATURES WILL HAVE FALLEN INTO THE POSITIVE
SINGLE DIGITS ACROSS THE MOUNTAINS...AND INTO THE LOW TO MID TEENS
ACROSS THE PIEDMONT. THESE COLD TEMPERATURES...WHEN FACTORING IN THE
STRONG WINDS...WILL CAUSE WIND CHILLS TO RANGE FROM NEAR ZERO ACROSS
THE SOUTHSIDE...TO THE NEGATIVE TEENS WEST OF THE BLUE RIDGE...
POSSIBLY AS LOW AS -30F IN A FEW SPOTS ALONG THE INTERSTATE 64
CORRIDOR. WIND SPEEDS WILL DECREASE HEADING INTO FRIDAY AFTERNOON...
ALLOWING WIND CHILLS TO RISE ABOVE ZERO MOST LOCATIONS. WINDS WILL
SHIFT MORE WESTERLY LATE IN THE DAY...WITH CLOUD COVER DECREASING...
WHICH WILL HELP AFTERNOON TEMPERATURES REBOUND INTO THE LOW 20S WEST
AND THE LOW 30S EAST. FRIDAY NIGHT TEMPERATURES WILL NOT BE AS
CHILLY...HOLDING IN THE TEENS MOST LOCATIONS.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 300 PM EST MONDAY...
BOTH THE GFS AND ECMWF KEEP NORTHWEST FLOW WITH A TROUGH/LOW NEAR
JAMES BAY AND RIDGING OVER THE WESTERN U.S. THROUGH SUNDAY.
A SHORTWAVE TROUGH IS FORECASTED TO ROTATE AROUND THE LONGWAVE
PATTERN THROUGH THE GREAT LAKES REGION AND INTO NEW ENGLAND.
THE SOUTHERN EXTENT OF THE ENERGY AND MOISTURE WITH THIS FEATURE IS
SLIGHTLY DIFFERENT DEPENDING ON MODEL CHOICE. STILL LEANING TOWARDS
THE DRIER AND LESS AMPLIFIED SOLUTION WITH RICHER MOISTURE NORTH OF
THE AREA. PLACED ISOLATED TO SCATTERED POPS IN THE WEST WITH THE
BEST CHANCES IN THE NORTHWEST FOR SATURDAY INTO SATURDAY NIGHT.
WINDS INCREASE SATURDAY INTO SATURDAY NIGHT WITH HEALTHY 4 TO 8 MB 6
HOUR PRESSURE RISES. HIGHS ON SATURDAY WILL VARY FROM THE LOWER 20S
IN THE NORTHWEST MOUNTAINS TO THE LOWER 40S IN THE PIEDMONTS.
THE COMBINATION OF WINDS AND TEMPERATURES WILL PRODUCE WIND CHILLS
BELOW ZERO AT THE HIGHER ELEVATIONS SATURDAY NIGHT INTO SUNDAY
MORNING. ACTUAL LOW TEMPERATURES SATURDAY WILL DROP INTO SINGLE
DIGITS TO MID TEENS. HIGH PRESSURE WILL SLOWLY SLIDE EAST SUNDAY
INTO SUNDAY NIGHT. HIGHS SUNDAY WILL VARY FRO THE MID TEENS IN THE
NORTHWEST TO LOWER 30S IN THE SOUTHEAST. ANOTHER COLD SUNDAY NIGHT
WITH LOW TEMPERATURES GENERALLY FROM THE SINGLE DIGITS AND TEENS.
THE HIGH CENTER MOVES SOUTHEAST ON MONDAY AND UPPER FLOW FLATTENS.
THE HIGH CENTER PUSHES OFF INTO THE ATLANTIC OCEAN MONDAY NIGHT INTO
TUESDAY. A COLD FRONT APPROACHES FROM THE WEST ON TUESDAY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 705 AM EST TUESDAY...
THERE WAS IFR FOG AND FREEZING FOG ALONG THE WEST SLOPES OF THE
APPALACHIANS EARLY THIS MORNING. MODELS WERE SUGGESTING LITTLE
IMPROVEMENT IN THE IFR CONDITIONS AT KBLF BEFORE NOON.
WESTERN EDGE OF A LARGE SHIELD OF PRECIPITATION EXTENDED FROM
KLYH TO KMTV THIS MORNING WITH WIDESPREAD MVFR CEILINGS AND
VISIBILITIES WITHIN THE PRECIPITATION...INCLUDING AT KLYH AND
KDAN. GETTING A FEW REPORTS OF SNOW MIXING IN WITH THE FAR
WESTERN EDGE OF THE PRECIPITATION.
EXPECTING THE RAIN TO END AT KLYH AND KDAN BY 17Z/NOON BASED ON
THE HRRR AND LOCAL WRF MODELS. BUT LOW CONFIDENCE ON THE TIMING
OF CEILINGS AND VISIBILITIES TODAY. THE EARLIEST THERE MAY BE ANY
VFR CEILINGS IS 20Z/3PM. AS LOW PRESSURE DEEPENS OFF THE COAST
TODAY...ENOUGH OF A PRESSURE GRADIENT FOR WIND GUSTS AROUND 20
KNOTS AT KLYH AND KDAN.
HIGH PRESSURE BUILDS IN OVER THE MOUNTAINS TONIGHT RESULTING IN
LIGHT AND VARIABLE WINDS. HAVE ADDED IFR FOG AND CEILINGS IN AT
KBLF AND KLWB OVERNIGHT WITH MEDIUM CONFIDENCE OF FOG FORMATION.
EXTENDED AVIATION DISCUSSION...
HIGH PRESSURE AND COLDER AIR WILL BUILD IN BEHIND THE COLD FRONT
WITH VFR FOR WEDNESDAY.
UPSLOPE SNOW SHOWERS ARE EXPECTED IN THE MOUNTAINS ON WEDNESDAY
NIGHT AND THURSDAY ALONG WITH A SHARP DROP IN TEMPERATURES
THURSDAY AND THURSDAY NIGHT BEHIND AN ARCTIC COLD FRONT. WIND
GUSTS BEHIND THE FRONT ON THURSDAY NIGHT MAY REACH 40-50 KNOTS IN
THE HIGHER ELEVATIONS.
HIGH PRESSURE BUILDS IN ALLOWING FOR DIMINISHING WINDS ON FRIDAY
WITH SOME LINGERING MVFR CIGS POSSIBLE OVER THE SOUTHEAST WEST VA
LOCATIONS.
ANOTHER FAST MOVING ARCTIC FRONT ARRIVES SATURDAY WITH A
RESUMPTION OF UPSLOPE SNOW SHOWERS INCLUDING MVFR CIGS/VSBYS ALONG
WITH INCREASING NORTHWEST WINDS THAT COULD AGAIN GUST TO 50 KNOTS
BY LATE IN THE DAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...NF
LONG TERM...KK
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
409 AM CST TUE FEB 10 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM CST TUE FEB 10 2015
AT 3 PM...A VIGOROUS VORT MAX WAS LOCATED OVER SOUTH CENTRAL SOUTH
DAKOTA. THIS SYSTEM SHOWS UP REALLY WELL ON THE WATER VAPOR
IMAGERY. SIOUX FALLS AND ABERDEEN RADARS ARE ALREADY SHOWING SOME
CONVECTIVE ELEMENTS TO THEIR PRECIPITATION ECHOS OVER EASTERN
SOUTH DAKOTA. VAD WIND PROFILES SHOW STRONG 925 MB MOISTURE
TRANSPORT AHEAD OF THIS WAVE. HASTINGS NEBRASKA HAS A 925 MB WIND
OF 50 KNOTS AND SIOUX FALLS IS 25 KNOTS. THE 10.00Z MESO MODELS
ARE IN FAIRLY GOOD AGREEMENT THAT THIS SYSTEM WILL MOVE EAST TO
THE INTERSTATE 35 CORRIDOR BY NOON. AHEAD OF THIS WAVE THERE WILL
BE STRONG 900 TO 800 MB AND 700 TO 500 MB FRONTOGENESIS. THIS
IS LOCATED BELOW A LAYER INSTABILITY LOCATED BETWEEN 500 AND
300 MB. LAPSE RATES IN THIS LAYER ARE RUNNING 8 TO 9 C/KM. IN
ADDITION...CAPES ARE RUNNING UP TO 200 J/KG ALONG AND SOUTH OF
INTERSTATE 94. DUE TO THIS INSTABILITY ADDED ISOLATED THUNDER TO
THE FORECAST. THIS CONVECTION GREATLY COMPLICATES THE
PRECIPITATION TYPE THE FORECAST AS IT COULD RESULT IN SLEET AND
SNOW. IN ADDITION...THE CONVECTION COULD INCREASE THE SNOW RATES.
THIS BAND OF PRECIPITATION WILL LAST 2 TO 3 HOURS...AND THEN
TRANSITION TO FREEZING DRIZZLE/DRIZZLE AS WE LOSE ICE. SOME OF THE
MESO MODELS SHOW THAT AS THE COMMA HEAD /ASSOCIATED WITH THE VORT
MAX/ MOVES ACROSS THE AREA...THERE COULD BE THE TRANSITION BACK TO
SNOW AGAIN. TOTAL SNOW AMOUNTS OF 2 TO 4 INCHES OF SNOW LOOK
LIKELY ACROSS CLARK AND TAYLOR COUNTIES FROM THIS AFTERNOON
THROUGH MIDNIGHT...1 TO 2 INCHES ALONG AND NORTH OF INTERSTATE
90...AND LESS THAN AN INCH ACROSS NORTHEAST IOWA AND SOUTHWEST
WISCONSIN. IN ADDITION TO THE SNOW...THERE WILL UP TO A TENTH OF
AN INCH OF ICE. DUE TO THE COMBINATION OF WINTER PRECIPITATION
TYPES...ISSUED A WINTER WEATHER ADVISORY FOR MOST OF THE AREA. THE
ONLY EXCEPTION ARE FAYETTE AND CLAYTON COUNTIES IN NORTHEAST
IOWA...AND GRANT COUNTY IN SOUTHWEST WISCONSIN.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 409 AM CST TUE FEB 10 2015
ON WEDNESDAY MORNING...STRONG COLD AIR ADVECTION WILL MOVE INTO
THE AREA. THIS WILL CAUSE TEMPERATURES TO SLOWLY FALL.
ON WEDNESDAY AFTERNOON AND NIGHT...THE MODELS CONTINUE TO SHOW
THAT A VIGOROUS SHORT WAVE TROUGH WILL MOVE SOUTH THROUGH THE
AREA. WITH 950 TO 900 MB LAPSE RATES AROUND 8 C/KM...THERE WILL BE
ENOUGH INSTABILITY FOR ISOLATED TO SCATTERED SNOW SHOWERS.
ADDITIONAL SNOWFALL AMOUNTS WILL BE LESS THAN A HALF INCH. IN
ADDITION TO THE SNOW...NORTHWEST WINDS WILL GUST INTO THE 30 TO 40
MPH RANGE WEST OF THE MISSISSIPPI RIVER AND 20 TO 30 MPH ACROSS
THE REMAINDER OF THE AREA. THIS COULD CAUSE SOME BLOWING AND
DRIFTING SNOW ALONG AND NORTH OF INTERSTATE 90.
ON FRIDAY NIGHT AND SATURDAY MORNING...THE MODELS HAVE SHIFTED
THE NEXT STRONG SHORT WAVE A BIT FURTHER EAST. AS A RESULT...THE
STRONGEST WIND GUSTS WILL JUST MISS OUR AREA. HOWEVER...THEY WILL
STILL GUST INTO THE 25 TO 35 MPH RANGE ACROSS WESTERN
WISCONSIN...AND 20 TO 30 MPH WEST OF THE MISSISSIPPI RIVER.
WITH OUR AREA BEING IN THE WESTERN PERIPHERY OF THIS COLD AIR
MASS...WE CONTINUE TO SEE SOME UNCERTAINTY WITH THE TEMPERATURES.
HOWEVER THE ECMWF STANDARD DEVIATIONS HAVE DROPPED FROM WHERE
THEY WERE YESTERDAY. SATURDAY CONTINUES TO LOOK LIKE THE COLDEST
DAY. OUR CURRENT FORECAST FOR THAT DAY STILL LOOKS TO BE A BIT
TOO WARM COMPARED TO THE GFS AND ECMWF GUIDANCE. IF THIS TREND
CONTINUES...WE MAY HAVE TO DROP IT ANOTHER 5 DEGREES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1116 PM CST MON FEB 9 2015
SHORT WAVE TROUGH CURRENTLY OVER EASTERN WYOMING WILL CONTINUE TO
MOVE NORTHEAST AND ACROSS THE REGION TUESDAY. THE 10.00Z NAM SHOWS
THAT THIS WAVE SHOULD BE ABLE TO PRODUCE A SHORT PERIOD OF STRONG
PV ADVECTION IN THE 500-300 MB LAYER TUESDAY AFTERNOON. AS A WEAK
SURFACE LOW TRACKS ACROSS CENTRAL MINNESOTA...A WARM FRONT IS
EXPECTED TO COME ACROSS WITH THE SHORT WAVE TROUGH WITH 5 TO 6
UBAR/S OF UP GLIDE ON THE 285K ISENTROPIC SURFACE ALONG AND BEHIND
THE WARM FRONT. THE FRONTOGENESIS LOOKS TO BE VERY WEAK AND
DISORGANIZED WITH THIS SYSTEM. THE RAP FOR SEVERAL RUNS HAS BEEN
SUGGESTING THAT SOME WEAK INSTABILITY COULD COME IN WITH THIS
SYSTEM WITH UP TO 100 J/KG OF MU CAPE IN THE WARM SECTOR AND TRIES
TO SHOW THE SNOW GOING CONVECTIVE WITH RATES OF 1 TO 2 INCHES PER
HOUR. HOWEVER...THE HRRR KEEPS THESE CONDITIONS FARTHER
NORTH...CLOSER TO THE SURFACE LOW AND SHORT WAVE TROUGH WHILE THE
NAM DOES NOT SHOW THIS AT ALL. FOR NOW...FEEL THE RAP IS A BIT OF
AN OUTLIER AND WILL NOT INDICATE ANY CONVECTIVE SNOWS. THERE
SHOULD STILL BE ENOUGH FORCING FOR A GOOD BURST OF SNOW ALONG AND
BEHIND THE WARM FRONT WITH BOTH TAF SITES GOING DOWN TO IFR FOR A
TWO TO THREE HOUR PERIOD BEFORE LIKELY COMING BACK UP TO MVFR. HOW
LONG THE LIGHT SNOW THEN PERSISTS IS SOMEWHAT QUESTIONABLE. WITH
THE BEST FORCING OFF TO THE EAST WITH THE SHORT WAVE
TROUGH...THERE IS JUST SOME WEAK ISENTROPIC UP GLIDE IN THE WARM
SECTOR. IF THIS IS ENOUGH TO PRODUCE SOME PRECIPITATION...THE NAM
WOULD SUGGEST A LOSS OF ICE FOR A CHANCE OF FREEZING DRIZZLE
TUESDAY EVENING. FOR NOW...HAVE NOT INCLUDED THIS AS CONFIDENCE IS
NOT HIGH ENOUGH THAT THERE WILL BE ANY PRECIPITATION AT THAT TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR WIZ032.
WINTER WEATHER ADVISORY FROM NOON TODAY TO MIDNIGHT CST TONIGHT
FOR WIZ017-029-033-034-041>044-053>055.
MN...WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR MNZ079-086>088-094>096.
IA...WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR IAZ008>011-018-019.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...04
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
322 PM CST TUE FEB 10 2015
.UPDATE...1223 PM CST
NO BIG CHANGES/UPDATES AT THIS TIME...ONLY MAKING SOME MINOR
CHANGES TO SKY COVER AND TEMPS FOR THIS AFTERNOON. CONTINUING TO
MONITOR TRENDS FOR POSSIBLE PRECIP LATER THIS EVENING...WITH
LATEST RADAR MOSAIC SHOWING STEADILY EASTWARD MOVING AREA OF
PRECIP MOVING THROUGH IOWA. HAVE MAINTAINED SLIGHT CHANCE WORDING
FOR THE WEST/NORTHWEST CWA LATE THIS AFTERNOON WITH THIS STEADY
PUSH...AS CURRENT TIMING STILL LOOKS GOOD. MUCH DRIER AIR IN PLACE
WILL LIKELY LIMIT DURATION AND COVERAGE OF ANY LIGHT PRECIP THAT
MOVES INTO THE CWA LATER THIS EVENING...AS WELL AS PRECIP TYPE
WITH A WINTRY MIX STILL APPEARING POSSIBLE. WILL LIKELY INCREASE
POPS ACROSS THE FAR NORTHERN CWA THIS EVENING BUT WITH SOME SHORT
TERM GUIDANCE HINTING THAT THE SOUTHERN END COULD WORK ITS WAY
FURTHER EAST INTO THE CWA...WILL WAIT TO MAKE ANY FINAL DECISIONS
THIS AFTERNOON.
RODRIGUEZ
&&
.SHORT TERM...
259 AM CST
THROUGH WEDNESDAY...
SFC RIDGE HAS PUSHED OVER THE REGION...HOWEVER WITH THE LACK OF
STRONG MIXING...A NARROW CHANNEL OF LAKE EFFECT CLOUDS/STRATUS
CONTINUES TO STRETCH SOUTH/SOUTHWEST ACROSS THE LAKE INTO
NORTHEAST IL. THE SOUTHERN PORTIONS OF THE LAKE STRATUS IS
BEGINNING TO THIN...HOWEVER EXPECT THIS FEATURE TO REMAIN THRU
DAYBREAK AND SLOWLY SLIDE NORTHWEST BY MID-MORNING. CLEAR SKIES
CONTINUE FOR OUR WESTERN CWFA WHERE THE LAKE STRATUS HAS NOT
INVADED...WHICH HAS ALLOWED AN IDEAL SCENARIO OF LIGHT WINDS AND
EFFICIENT RADIATIVE PROCESSES TO TAKE PLACE. SFC OBS WILL LIKELY
DIP TO ARND ZERO TO POSSIBLY A FEW DEGREES BELOW ZERO IN THE
TRADITIONAL COLD SPOTS BEFORE DAYBREAK. ELSEWHERE TEMPS HAD
DROPPED...HOWEVER WITH THE CLOUD DECK PIVOTING WEST/NORTHWEST
TEMPS HAVE COME BACK UP A COUPLE OF DEGREES. LLVL FLOW HAS ALREADY
TURNED EASTERLY/SOUTHEASTERLY ACROSS CENTRAL IOWA INTO SOUTHERN
IL.
WITH THE ANTI-CYCLONIC FEATURE SLOWLY PUSHING EAST TODAY...LLVL FLOW
WILL INCREASE FROM THE EAST/SOUTHEAST ALLOWING A STEADY CONVEYOR OF
DRIER AIR TO PUSH ACROSS THE FORECAST AREA. THIS WILL LIKELY DELAY
SATURATION IN ADVANCE OF THE NEXT SYSTEM...WHICH IS POISED TO ARRIVE
EARLY THIS EVENING. WARM AIR ADVECTION WILL NUDGE TEMPS UP THIS AFTN
TO ARND 30-35 DEG RANGE. THE BEST FORCING FROM THE SHORTWAVE LOOKS
TO BE CONFINED TO WISC...HOWEVER SOME FORCING WILL EXTEND SOUTH INTO
THE NORTHERN PORTIONS OF THE FORECAST AREA. SOUNDINGS SUGGEST A
LINGERING THERMAL INVERSION THIS EVENING...WHICH COULD ALLOW FOR
SOME PARTIAL MELTING OF DENDRITES OR POSSIBLY A SNOW/SLEET MIX. ANY
ACCUMULATIONS WOULD BE LOCATED ALONG THE IL/WISC STATELINE. BUT A
QUICK HALF INCH IS POSSIBLE BEFORE THE VORT LIFTS NORTHEAST EARLY
WED.
THE TRAILING FRONTAL BOUNDARY IS PROGGED TO HOLD OFF UNTIL DAYBREAK
WED...WHICH COULD ALLOW TEMPS PRIOR TO DAYBREAK TO WARM A FEW
DEGREES INTO THE LOW 30S. THEN MUCH COLDER AIR WILL ADVECT SOUTHEAST
ACROSS THE CWFA...ALLOWING TEMPS TO STEADILY COOL THROUGHOUT THE
DAY. BY EARLY WED AFTN TEMPS WILL MAINLY BE IN THE MID/UPR 20S
ACROSS THE WEST/NORTH CWFA AND STILL IN THE LOW 30S FOR THE
SOUTHEAST FORECAST AREA.
A DRY WEDGE IS PROGGED TO ARRIVE WED...AND SHOULD BRING A TEMPORARY
LULL IN ANY LGT SNOW/FLURRIES FOR THE CWFA WED AFTN. THEN THE 500MB
VORT QUICKLY SLIDES SOUTH FROM CANADA INTO THE UPPER MIDWEST...AND
WILL ARRIVE OVER THE CWFA WED NGT. ROBUST THERMAL TROUGH AT 850MB
BRINGS TEMPS DOWN TO -20 TO -24 DEG C LATE WED NGT. LOWERED TEMPS
WED NGT A FEW DEGREES INTO THE SINGLE DIGITS ABOVE ZERO...HOWEVER
THIS MAY NEED TO BE LOWERED FURTHER GIVEN THE STRENGTH OF THE COLD
AIR ADVECTION.
LAKE EFFECT MACHINE WILL BE STARTING TO KICK-IN LATE WED
NGT...HOWEVER WITH A MORE NORTHWEST FLOW THIS WILL LIKELY KEEP THE
BULK OF THE ACTIVITY EAST OF PORTER COUNTY INDIANA.
BEACHLER
&&
.LONG TERM...
259 AM CST
THURSDAY THROUGH MONDAY...
STRONG ARCTIC HIGH PRESSURE ARRIVES THUR ACROSS THE UPPER
MIDWEST/MID-MISSOURI VALLEY...WITH A TIGHT PRESSURE GRADIENT
REMAINING OVER THE FORECAST AREA THUR. THIS WILL ALLOW WINDS TO TURN
MORE NORTHERLY...ALLOWING A LONG FETCH SETUP FOR LAKE EFFECT SNOW TO
PUSH WEST INTO LAKE/PORTER COUNTIES INDIANA AND POSSIBLY INTO
NEWTON/JASPER COUNTIES AS WELL. FURTHER WEST SKIES SHUD THIN...WITH
P-CLOUDY TO POSSIBLY SUNNY SKIES BY MID AFTN THUR. THE POTENT
THERMAL TROUGH WILL REMAIN OVERHEAD...WITH SFC TEMPS STRUGGLING TO
WARM BEYOND THE SINGLE DIGITS ABOVE ZERO. WHERE THE LAKE CLOUDS/SNOW
WILL BE TEMPS WILL BE IN THE LOW TEENS. SOUNDINGS SUGGEST UP TO
100J/KG OF CAPE OVER THE LAKE MAY DEVELOP THUR...SO CONDITIONS WILL
BE FAVORABLE FOR A POTENT LES BAND TO DEVELOP. ACCUMULATIONS WILL BE
POSSIBLE FOR NORTHWEST IN...BUT THE LOCATIONS WILL BE DICTATED BY
THE WIND DIRECTION.
WINDS WILL BEGIN TO RELAX AS THE SFC RIDGE SLIDES EAST OVER THE
REGION...AND YET ANOTHER CLIPPER ARRIVES FRI. TEMPS THUR NGT WILL
HINGE ON CLOUD COVER. CURRENT SOLUTIONS SUGGEST MOST OF THE AREA
WILL OBSERVE TEMPS AROUND ZERO TO A FEW DEGREES BELOW ZERO. WINDS
WILL KEEP WIND CHILLS IN THE -15 TO -20 DEG RANGE THUR EVE...BUT
SHOULD WEAKEN DURING THE OVERNIGHT HOURS.
FAST NORTHWEST FLOW WILL CONTINUE THE ACTIVE THEME...AS ANOTHER
SHORTWAVE SLIDES ACROSS THE UPPER MIDWEST FRI. THE NEXT WAVE WILL
LIKELY ARRIVE WITH THICKENING CLOUDS AND POSSIBLY LGT SNOW FRI. COOL
AIR REMAINS WITH HIGHS FRI IN THE TEENS/LOW 20S.
SATURDAY THROUGH EARLY NEXT WEEK...
THE AMPLIFIED RIDGING ACROSS WESTERN CANADA/CONUS WILL WEAKEN
MARGINALLY HEADING INTO THE WEEKEND AND NUDGE EAST. THIS SHOULD HELP
TO KICK THE POTENT THERMAL TROUGH EAST OF THE FORECAST
AREA...HOWEVER THE LONGWAVE PATTERN CONTINUES TO POINT TOWARDS A
REDEVELOPMENT TO THE HIGH AMPLITUDE RIDGE OVER EASTERN ALASKA EARLY
NEXT WEEK. WHILE A PERIOD OR TWO COULD REMAIN DRY...IT IS LIKELY
THAT A FEW CLIPPERS WILL BREAK SOUTHEAST FROM CENTRAL CANADA AND
PIVOT OVER THE GREAT LAKES...PRODUCING SOME LGT SNOW.
TEMPS WILL CONTINUE TO BE ON THE COOL SIDE WITH HIGHS IN THE TEENS
TO LOW 20S...HOWEVER HEADING INTO EARLY NEXT WEEK THE MID-LVL RIDGE
MAY BRIEFLY TRANSITION TOWARDS QUASI-ZONAL AND OFFER BREAK WITH
TEMPS APPROACHING 30 DEGREES EARLY NEXT WEEK. UNFORTUNATELY THIS
BRIEF MODERATION ONLY LOOKS TEMPORARY AS COLD AIR WILL RETURN BY THE
MIDDLE OF NEXT WEEK.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* CHANCE OF LIGHT SNOW...POSSIBLY MIXING WITH SLEET...LATE THIS
EVENING.
* CHANCE OF LIGHT FREEZING DRIZZLE LATE TONIGHT WITH MVFR VIS
LIKELY.
* MVFR CIGS LATE TONIGHT INTO WEDNESDAY MORNING.
KREIN
//DISCUSSION...UPDATED 18Z...
MAIN FORECAST CONCERNS FOCUS ON WIND DIRECTION TRENDS THROUGH THE
PERIOD AS WELL AS POTENTIAL FOR A COUPLE PERIODS OF WINTRY PCPN
OVERNIGHT. THE MAIN SYSTEM RESPONSIBLE IS A WEAK CLIPPER TYPE
SYSTEM CURRENTLY TRACKING ACROSS THE UPPER MISSISSIPPI VALLEY.
SKIES HAVE IMPROVE TO VFR FOLLOWING THE EROSION OF THE ST
DECK...BUT LATEST SATELLITE TRENDS INDICATE THAT INCREASING MID
AND HIGH CLOUD SHOULD BEGIN TO OVERSPREAD THE AREA LATE THIS
AFTERNOON. AS THE CLIPPER APPROACHES THE REGION...WINDS WILL
GRADUALLY VEER FROM GENERALLY ELY TO SELY LATE THIS
AFTERNOON...BUT WITH A WEAK GRADIENT IN PLACE...WIND SPEEDS WILL
BE LIGHT AND DIRECTION SHOULD BE SOMEWHAT VARIABLE...WITH SPEEDS
AT OR UNDER 8KT. WINDS SHOULD THEN CONTINUE TO VEER THROUGH SLY
LATE THIS EVENING TO SWLY BY TOMORROW MORNING.
THE BIGGER CONCERN WILL BE THE CHANCES FOR PCPN AT THE TERMINAL.
LATEST RADAR TRENDS SHOW A NARROW BAND OF PCPN MOVING THROUGH ERN
IOWA THIS AFTERNOON...WITH THE LATEST HIGH RES MODEL GUIDANCE
SUGGESTING THAT PCPN COULD REACH THE RFD AREA BY ARND
02-03Z...WHICH IS A FEW HOURS SLOWER THAN PREVIOUS THINKING. THE
RH AND TEMPERATURE PROFILES ARE A BIT TRICKY IN DETERMINING PCPN
TYPE AS THERE IS A WEDGE OF WARMER AIR ALOFT WITH TEMPS ABOVE 0C
WITH A FREEZING LAYER ABOVE AND NEAR THE SURFACE. THIS TYPE OF
THERMAL AND MOISTURE PROFILE IS SIMILAR FROM WEST TO EAST...WITH
THE MAIN ISSUE AS THE SYSTEM CROSSES THE REGION BEING THE TRACK OF
THE STRONGEST MID LEVEL FORCING...WHICH IN TURN WOULD TRANSLATE
INTO THE GREATER CHANCES FOR PCPN REACHING THE SURFACE. THE LATEST
GUIDANCE SUGGESTS THAT THE STRONGEST FORCING WILL BE OVER THE
NORTHERN TIER COUNTIES OF IL...WITH RFD BEING THE TERMINAL WITH
THE GREATEST CHANCE TO SEE PCPN. CONSIDERING THE THERMAL PROFILE
AND FORCING...PCPN COULD BE A SNOW/SLEET MIX. AS THE SYSTEM TRACKS
EWD...THE MID LEVEL FORCING SHOULD WEAKEN AND TREND NORTH OF THE
CHICAGO AREA TERMINALS. WILL CONTINUE WITH THE PROB30 GROUP FOR
3SM -SN FOR NOW...BUT CONFIDENCE IS LOW...WITH PROBABLY EQUAL
CHANCES THAT ANY PCPN WOULD REMAIN NORTH OF THE TERMINALS...OR
THERE COULD BE A BRIEF PERIOD OF A SNOW/SLEET MIX.
AFTER MIDNIGHT...THE SNOW/SLEET POTENTIAL WILL COME TO AN END WITH
DRIER AIR OVERSPREADING THE AREA ABOVE ARND 8KFT...WITH A
SATURATED LAYER BELOW. WITH LITTLE FORCING ALOFT AND DRY
AIR...THERE WILL LITTLE OPPORTUNITY FOR ICE PRODUCTION ALOFT...SO
SOME LIGHT FREEZING DRIZZLE WILL BE POSSIBLE FOR THE EARLY MORNING
HOURS. THIS IS ALSO A LOW CONFIDENCE FORECAST DEPENDING ON HOW
QUICKLY DEEP LAYER DRY AIR MOVES OVER THE REGION...WHICH WOULD
LIMIT THE DURATION OF ANY FZDZ.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS THROUGH THE PERIOD.
* LOW CONFIDENCE IN EXTEND LIGHT SNOW/ICE PELLETS THIS EVENING...
AND POSSIBLE TIMING.
* LOW TO MEDIUM CONFIDENCE IN FREEZING DRIZZLE FOR LATE TONIGHT.
* MEDIUM TO HIGH CONFIDENCE IN MVFR CIGS LATE TONIGHT INTO
WEDNESDAY MORNING.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT...CHANCE OF SNOW. MVFR POSSIBLE. STRONG/GUSTY
NORTHWEST WINDS.
* THURSDAY...CHANCE OF FLURRIES. MVFR POSSIBLE. STRONG/GUSTY
NORTHWEST WINDS.
* FRIDAY...SLIGHT CHANCE OF SNOW. MVFR POSSIBLE. WEST/SOUTHWEST
WINDS.
* SATURDAY...CHANCE OF FLURRIES. MVFR POSSIBLE. VERY STRONG/GUSTY
NORTHWEST WINDS.
* SUNDAY...DRY/VFR. WEST/SOUTHWEST WINDS.
* MONDAY...MVFR POSSIBLE. SOUTHWEST WINDS.
&&
.MARINE...
322 PM CST
MULTIPLE MARINE CONCERNS AS WE ENTER A VERY COLD AND ACTIVE PATTERN.
THIS EVENING...THERE COULD BE BRIEF WINDOW OF NEAR SMALL CRAFT
CONDITIONS ALONG THE FAR NORTHEAST ILLINOIS SHORE AS SOUTHEAST
WINDS INCREASE TO 15 TO 25 KT. WINDS WILL THEN SHIFT SOUTHERLY ON
THE ENTIRE LAKE AS A WEAK LOW OVER THE UPPER MIDWEST APPROACHES.
THERE COULD BE A FEW GUSTS TO 30 KT ON THE NORTHERN HALF OF THE
LAKE TONIGHT IN THE PEAK OF THE SOUTHERLY FLOW.
A STRONG COLD FRONT TRAILING FROM THE LOW WILL SWEEP ACROSS THE LAKE
BY MID DAY WEDNESDAY OR SO...WITH AN EXPANSIVE 1040+ MB ARCTIC HIGH
SPREADING IN FROM THE NORTHERN PLAINS BEHIND IT. VERY TIGHT PRESSURE
GRADIENT AND BITTERLY COLD AIR MASS WILL ENABLE WINDS TO QUICKLY
RAMP UP TO GALE FORCE BY EARLY WEDNESDAY EVENING FOR THE OPEN WATERS
THEN LATER IN THE EVENING FOR THE NEARSHORE. IN ADDITION...HEAVY
FREEZING SPRAY WILL DEVELOP AS AIR TEMPERATURES PLUMMET. HAVE ISSUED
A GALE WARNING AND HEAVY FREEZING SPRAY WARNING FOR THE LAKE
WEDNESDAY EVENING/NIGHT INTO THURSDAY AFTERNOON...WITH A SMALL CRAFT
LEADING UP TO THE GALE WARNING FOR THE NEAR SHORE WEDNESDAY
AFTERNOON AND EVENING. EXPECTING PEAK GUSTS UP TO 40 KT WITH THIS
EVENT...AND THERE IS SOME POTENTIAL FOR UP TO 45 KT IN/NEAR THE
LAKE EFFECT CONVERGENCE BAND EARLY THURSDAY MORNING.
THERE WILL BE ONLY A BRIEF CALMER PERIOD THURSDAY NIGHT INTO
FRIDAY...FOLLOWED BY YET ANOTHER STRONG ARCTIC FRONT SWEEPING ACROSS
THE LAKE FRIDAY EVENING/NIGHT. VERY SIMILAR SETUP TO WEDNESDAY NIGHT
INTO THURSDAY BUT AN EVEN TIGHTER PRESSURE GRADIENT DUE TO STRONGER
LOW PRESSURE TO THE EAST SHOULD RESULT IN AT LEAST GALES TO 45 KT
AND HEAVY FREEZING SPRAY. WINDS...WAVES AND FREEZING SPRAY WILL
DIMINISH LATER SATURDAY NIGHT INTO SUNDAY AS THE ARCTIC HIGH MOVES
OVER THE LAKE.
RC
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...NOON WEDNESDAY TO MIDNIGHT THURSDAY.
HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364-
LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-
LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-
LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...MIDNIGHT
THURSDAY TO 3 PM THURSDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...MIDNIGHT THURSDAY TO 3 PM THURSDAY.
GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...6 PM WEDNESDAY TO 3 PM
THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
300 PM CST Tue Feb 10 2015
.SHORT TERM...(Tonight)
ISSUED AT 258 PM CST TUE FEB 10 2015
Stratocumulus clouds 1.5-2k ft are now west of I-55 and eroding and
will continue to decrease toward the nw over IL river valley late
this afternoon into early this evening due to influence of high
pressure ridge axis into IL. HRRR model has been handling the
clearing of low clouds well and will continue to follow its lead.
Broken to overcast mid level clouds 8-12k ft over IA and far nw IL
will spread east across central IL during this evening especially
north of I-72 where skies become mostly cloudy. These clouds ahead
of 1010 mb low pressure along the eastern ND/SD border will track
ene to the Keweenaw peninsula in upper MI by 12Z/6 am Wed with its
cold front moving toward the IL river. Meanwhile southeast IL will
likely stay in the clear most of this evening with skies becoming
partly cloudy overnight in southeast IL. Light mix of precipitation
over eastern IA and moving east into WI and far NW IL at mid
afternoon. Forecast models keep light precipitation north of I-80
tonight over northern IL. Lows tonight in the upper 20s to near 30F
with mildest readings from Springfield southwest. ESE winds less
than 10 mph to veer ssw during overnight and turn WNW nw of IL by
sunrise behind cold front.
&&
.LONG TERM...(Wednesday through Tuesday)
ISSUED AT 258 PM CST TUE FEB 10 2015
The extended will be dominated by large temperature variations,
highlighted by two surges of Arctic air into the western Great Lakes
and eastern CONUS. Precipitation will be light with any shortwaves
through Monday.
The upper ridge along the West Coast will remain a semi-permanent
feature over the 5 to 6 days, with a long wave trough east of the
Continental Divide. A brief push of warm air into the area tonight
ahead of the first cold front should help Wednesday start out with
rising temps possibly even before sunrise. The cold front could
start pushing across our western counties shortly after sunrise, but
the affects of the cold air will be delayed across the rest of the
area until afternoon when the northwest winds increase in the strong
cold air advection. A few light snow showers or flurries could
develop Wed afternoon NE of CMI to DNV where a weak shortwave helps
provide some lift in the advancing cold air. A better chance for
snow showers in our area looks to be Wed night as a strong 500mb
vort max dives south into IL. Any snow accums would be very light
and mainly confined to areas NE of BMI to MTO. Flurries could extend
as far west as Springfield and Taylorville, depending on available
moisture.
Wind chills later Wed night will drop into the -5 to -15F range,
which is just outside of our advisory levels. However, those wind
chill numbers are for the sustained winds, and gusts to 30 mph could
easily push wind chills much colder than that at times.
Thursday will be a blustery day with NW winds of 20-25 and gusts to
35 mph. Some flurries cold linger east of I-57, but the shortwave
aloft will depart east of IL early in the day to help shut down
potential for precip.
Another brief warmup is indicated for Friday, as highs climb toward
freezing in the south and into the upper 20s north.
The strongest surge of Arctic air this week is expected late Friday
night and Saturday, as a deep closed low drops straight south from
the upper latitudes into the Great Lakes region. The coldest air,
with 850 mb temperatures around -25 to -28C, will be over our area
on Saturday. Strong N winds of 25 mph gusting to 40 mph will put
wind chills into the advisory criteria between -15F and -20F
starting Saturday morning across the northern CWA. Those bitterly
cold wind chills appear likely all the way through mid-morning on
Sunday. Temperatures on Sunday will warm slightly, but still remain
well below normal in the teens to around 20. Washington`s
Birthday/Monday looks to be much warmer with highs into the low to
mid 30s as a storm system approaches southern Illinois. Some
indications are for a period of rain or snow in portions of central
IL, with a band of measurable snow possible. The track of that
system has shifted farther south in the 12z GFS, keeping light snow
confined to areas south of I-72, but the ECMWF still has the effects
of the storm reaching well into IL with rain/snow south and snow
north. Will keep chance PoPs across the entire area Monday night for
now. Beyond that, there are indications of yet another push of cold
air for late Tuesday and Tuesday night.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 1155 AM CST TUE FEB 10 2015
MVFR clouds with bases of 1.3-2k ft have scattered out at CMI and
DEC during the morning and will scatter out at BMI and SPI between
19Z-21Z and at PIA 21Z-23Z. Broken mid level clouds 10-12k ft over
IA will arrive at PIA around 00Z and along I-55 at 01-02Z and CMI and
DEC at 02-04Z. 1010 mb low pressure along the eastern ND/SD border
to track east to A cold front to track into western Lake Superior
by dawn Wed and then push a cold front east to the IL river early
Wed morning and through DEC/CMI by late Wed morning. MVFR clouds
to occur along and behind this front while light precipitation
stays north of central IL. ESE winds less than 10 kts to become south
tonight and then brisk WNW 10-15 kts with gusts 15-20 kts after
15Z Wed behind cold front.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...07
LONG TERM...Shimon
AVIATION...07
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1203 PM CST TUE FEB 10 2015
.SHORT TERM...
259 AM CST
THROUGH WEDNESDAY...
SFC RIDGE HAS PUSHED OVER THE REGION...HOWEVER WITH THE LACK OF
STRONG MIXING...A NARROW CHANNEL OF LAKE EFFECT CLOUDS/STRATUS
CONTINUES TO STRETCH SOUTH/SOUTHWEST ACROSS THE LAKE INTO
NORTHEAST IL. THE SOUTHERN PORTIONS OF THE LAKE STRATUS IS
BEGINNING TO THIN...HOWEVER EXPECT THIS FEATURE TO REMAIN THRU
DAYBREAK AND SLOWLY SLIDE NORTHWEST BY MID-MORNING. CLEAR SKIES
CONTINUE FOR OUR WESTERN CWFA WHERE THE LAKE STRATUS HAS NOT
INVADED...WHICH HAS ALLOWED AN IDEAL SCENARIO OF LIGHT WINDS AND
EFFICIENT RADIATIVE PROCESSES TO TAKE PLACE. SFC OBS WILL LIKELY
DIP TO ARND ZERO TO POSSIBLY A FEW DEGREES BELOW ZERO IN THE
TRADITIONAL COLD SPOTS BEFORE DAYBREAK. ELSEWHERE TEMPS HAD
DROPPED...HOWEVER WITH THE CLOUD DECK PIVOTING WEST/NORTHWEST
TEMPS HAVE COME BACK UP A COUPLE OF DEGREES. LLVL FLOW HAS ALREADY
TURNED EASTERLY/SOUTHEASTERLY ACROSS CENTRAL IOWA INTO SOUTHERN
IL.
WITH THE ANTI-CYCLONIC FEATURE SLOWLY PUSHING EAST TODAY...LLVL FLOW
WILL INCREASE FROM THE EAST/SOUTHEAST ALLOWING A STEADY CONVEYOR OF
DRIER AIR TO PUSH ACROSS THE FORECAST AREA. THIS WILL LIKELY DELAY
SATURATION IN ADVANCE OF THE NEXT SYSTEM...WHICH IS POISED TO ARRIVE
EARLY THIS EVENING. WARM AIR ADVECTION WILL NUDGE TEMPS UP THIS AFTN
TO ARND 30-35 DEG RANGE. THE BEST FORCING FROM THE SHORTWAVE LOOKS
TO BE CONFINED TO WISC...HOWEVER SOME FORCING WILL EXTEND SOUTH INTO
THE NORTHERN PORTIONS OF THE FORECAST AREA. SOUNDINGS SUGGEST A
LINGERING THERMAL INVERSION THIS EVENING...WHICH COULD ALLOW FOR
SOME PARTIAL MELTING OF DENDRITES OR POSSIBLY A SNOW/SLEET MIX. ANY
ACCUMULATIONS WOULD BE LOCATED ALONG THE IL/WISC STATELINE. BUT A
QUICK HALF INCH IS POSSIBLE BEFORE THE VORT LIFTS NORTHEAST EARLY
WED.
THE TRAILING FRONTAL BOUNDARY IS PROGGED TO HOLD OFF UNTIL DAYBREAK
WED...WHICH COULD ALLOW TEMPS PRIOR TO DAYBREAK TO WARM A FEW
DEGREES INTO THE LOW 30S. THEN MUCH COLDER AIR WILL ADVECT SOUTHEAST
ACROSS THE CWFA...ALLOWING TEMPS TO STEADILY COOL THROUGHOUT THE
DAY. BY EARLY WED AFTN TEMPS WILL MAINLY BE IN THE MID/UPR 20S
ACROSS THE WEST/NORTH CWFA AND STILL IN THE LOW 30S FOR THE
SOUTHEAST FORECAST AREA.
A DRY WEDGE IS PROGGED TO ARRIVE WED...AND SHOULD BRING A TEMPORARY
LULL IN ANY LGT SNOW/FLURRIES FOR THE CWFA WED AFTN. THEN THE 500MB
VORT QUICKLY SLIDES SOUTH FROM CANADA INTO THE UPPER MIDWEST...AND
WILL ARRIVE OVER THE CWFA WED NGT. ROBUST THERMAL TROUGH AT 850MB
BRINGS TEMPS DOWN TO -20 TO -24 DEG C LATE WED NGT. LOWERED TEMPS
WED NGT A FEW DEGREES INTO THE SINGLE DIGITS ABOVE ZERO...HOWEVER
THIS MAY NEED TO BE LOWERED FURTHER GIVEN THE STRENGTH OF THE COLD
AIR ADVECTION.
LAKE EFFECT MACHINE WILL BE STARTING TO KICK-IN LATE WED
NGT...HOWEVER WITH A MORE NORTHWEST FLOW THIS WILL LIKELY KEEP THE
BULK OF THE ACTIVITY EAST OF PORTER COUNTY INDIANA.
BEACHLER
&&
.LONG TERM...
259 AM CST
THURSDAY THROUGH MONDAY...
STRONG ARCTIC HIGH PRESSURE ARRIVES THUR ACROSS THE UPPER
MIDWEST/MID-MISSOURI VALLEY...WITH A TIGHT PRESSURE GRADIENT
REMAINING OVER THE FORECAST AREA THUR. THIS WILL ALLOW WINDS TO TURN
MORE NORTHERLY...ALLOWING A LONG FETCH SETUP FOR LAKE EFFECT SNOW TO
PUSH WEST INTO LAKE/PORTER COUNTIES INDIANA AND POSSIBLY INTO
NEWTON/JASPER COUNTIES AS WELL. FURTHER WEST SKIES SHUD THIN...WITH
P-CLOUDY TO POSSIBLY SUNNY SKIES BY MID AFTN THUR. THE POTENT
THERMAL TROUGH WILL REMAIN OVERHEAD...WITH SFC TEMPS STRUGGLING TO
WARM BEYOND THE SINGLE DIGITS ABOVE ZERO. WHERE THE LAKE CLOUDS/SNOW
WILL BE TEMPS WILL BE IN THE LOW TEENS. SOUNDINGS SUGGEST UP TO
100J/KG OF CAPE OVER THE LAKE MAY DEVELOP THUR...SO CONDITIONS WILL
BE FAVORABLE FOR A POTENT LES BAND TO DEVELOP. ACCUMULATIONS WILL BE
POSSIBLE FOR NORTHWEST IN...BUT THE LOCATIONS WILL BE DICTATED BY
THE WIND DIRECTION.
WINDS WILL BEGIN TO RELAX AS THE SFC RIDGE SLIDES EAST OVER THE
REGION...AND YET ANOTHER CLIPPER ARRIVES FRI. TEMPS THUR NGT WILL
HINGE ON CLOUD COVER. CURRENT SOLUTIONS SUGGEST MOST OF THE AREA
WILL OBSERVE TEMPS AROUND ZERO TO A FEW DEGREES BELOW ZERO. WINDS
WILL KEEP WIND CHILLS IN THE -15 TO -20 DEG RANGE THUR EVE...BUT
SHOULD WEAKEN DURING THE OVERNIGHT HOURS.
FAST NORTHWEST FLOW WILL CONTINUE THE ACTIVE THEME...AS ANOTHER
SHORTWAVE SLIDES ACROSS THE UPPER MIDWEST FRI. THE NEXT WAVE WILL
LIKELY ARRIVE WITH THICKENING CLOUDS AND POSSIBLY LGT SNOW FRI. COOL
AIR REMAINS WITH HIGHS FRI IN THE TEENS/LOW 20S.
SATURDAY THROUGH EARLY NEXT WEEK...
THE AMPLIFIED RIDGING ACROSS WESTERN CANADA/CONUS WILL WEAKEN
MARGINALLY HEADING INTO THE WEEKEND AND NUDGE EAST. THIS SHOULD HELP
TO KICK THE POTENT THERMAL TROUGH EAST OF THE FORECAST
AREA...HOWEVER THE LONGWAVE PATTERN CONTINUES TO POINT TOWARDS A
REDEVELOPMENT TO THE HIGH AMPLITUDE RIDGE OVER EASTERN ALASKA EARLY
NEXT WEEK. WHILE A PERIOD OR TWO COULD REMAIN DRY...IT IS LIKELY
THAT A FEW CLIPPERS WILL BREAK SOUTHEAST FROM CENTRAL CANADA AND
PIVOT OVER THE GREAT LAKES...PRODUCING SOME LGT SNOW.
TEMPS WILL CONTINUE TO BE ON THE COOL SIDE WITH HIGHS IN THE TEENS
TO LOW 20S...HOWEVER HEADING INTO EARLY NEXT WEEK THE MID-LVL RIDGE
MAY BRIEFLY TRANSITION TOWARDS QUASI-ZONAL AND OFFER BREAK WITH
TEMPS APPROACHING 30 DEGREES EARLY NEXT WEEK. UNFORTUNATELY THIS
BRIEF MODERATION ONLY LOOKS TEMPORARY AS COLD AIR WILL RETURN BY THE
MIDDLE OF NEXT WEEK.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* CHANCE OF LIGHT SNOW AND...POSSIBLY...ICE PELLETS LATE THIS
EVENING.
* CHANCE OF LIGHT FREEZING DRIZZLE LATE TONIGHT.
* MVFR CIGS LATE TONIGHT INTO WEDNESDAY MORNING.
KREIN
//DISCUSSION...UPDATED 18Z...
MAIN FORECAST CONCERNS FOCUS ON WIND DIRECTION TRENDS THROUGH THE
PERIOD AS WELL AS POTENTIAL FOR A COUPLE PERIODS OF WINTRY PCPN
OVERNIGHT. THE MAIN SYSTEM RESPONSIBLE IS A WEAK CLIPPER TYPE
SYSTEM CURRENTLY TRACKING ACROSS THE UPPER MISSISSIPPI VALLEY.
SKIES HAVE IMPROVE TO VFR FOLLOWING THE EROSION OF THE ST
DECK...BUT LATEST SATELLITE TRENDS INDICATE THAT INCREASING MID
AND HIGH CLOUD SHOULD BEGIN TO OVERSPREAD THE AREA LATE THIS
AFTERNOON. AS THE CLIPPER APPROACHES THE REGION...WINDS WILL
GRADUALLY VEER FROM GENERALLY ELY TO SELY LATE THIS
AFTERNOON...BUT WITH A WEAK GRADIENT IN PLACE...WIND SPEEDS WILL
BE LIGHT AND DIRECTION SHOULD BE SOMEWHAT VARIABLE...WITH SPEEDS
AT OR UNDER 8KT. WINDS SHOULD THEN CONTINUE TO VEER THROUGH SLY
LATE THIS EVENING TO SWLY BY TOMORROW MORNING.
THE BIGGER CONCERN WILL BE THE CHANCES FOR PCPN AT THE TERMINAL.
LATEST RADAR TRENDS SHOW A NARROW BAND OF PCPN MOVING THROUGH ERN
IOWA THIS AFTERNOON...WITH THE LATEST HIGH RES MODEL GUIDANCE
SUGGESTING THAT PCPN COULD REACH THE RFD AREA BY ARND
02-03Z...WHICH IS A FEW HOURS SLOWER THAN PREVIOUS THINKING. THE
RH AND TEMPERATURE PROFILES ARE A BIT TRICKY IN DETERMINING PCPN
TYPE AS THERE IS A WEDGE OF WARMER AIR ALOFT WITH TEMPS ABOVE 0C
WITH A FREEZING LAYER ABOVE AND NEAR THE SURFACE. THIS TYPE OF
THERMAL AND MOISTURE PROFILE IS SIMILAR FROM WEST TO EAST...WITH
THE MAIN ISSUE AS THE SYSTEM CROSSES THE REGION BEING THE TRACK OF
THE STRONGEST MID LEVEL FORCING...WHICH IN TURN WOULD TRANSLATE
INTO THE GREATER CHANCES FOR PCPN REACHING THE SURFACE. THE LATEST
GUIDANCE SUGGESTS THAT THE STRONGEST FORCING WILL BE OVER THE
NORTHERN TIER COUNTIES OF IL...WITH RFD BEING THE TERMINAL WITH
THE GREATEST CHANCE TO SEE PCPN. CONSIDERING THE THERMAL PROFILE
AND FORCING...PCPN COULD BE A SNOW/SLEET MIX. AS THE SYSTEM TRACKS
EWD...THE MID LEVEL FORCING SHOULD WEAKEN AND TREND NORTH OF THE
CHICAGO AREA TERMINALS. WILL CONTINUE WITH THE PROB30 GROUP FOR
3SM -SN FOR NOW...BUT CONFIDENCE IS LOW...WITH PROBABLY EQUAL
CHANCES THAT ANY PCPN WOULD REMAIN NORTH OF THE TERMINALS...OR
THERE COULD BE A BRIEF PERIOD OF A SNOW/SLEET MIX.
AFTER MIDNIGHT...THE SNOW/SLEET POTENTIAL WILL COME TO AN END WITH
DRIER AIR OVERSPREADING THE AREA ABOVE ARND 8KFT...WITH A
SATURATED LAYER BELOW. WITH LITTLE FORCING ALOFT AND DRY
AIR...THERE WILL LITTLE OPPORTUNITY FOR ICE PRODUCTION ALOFT...SO
SOME LIGHT FREEZING DRIZZLE WILL BE POSSIBLE FOR THE EARLY MORNING
HOURS. THIS IS ALSO A LOW CONFIDENCE FORECAST DEPENDING ON HOW
QUICKLY DEEP LAYER DRY AIR MOVES OVER THE REGION...WHICH WOULD
LIMIT THE DURATION OF ANY FZDZ.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS THROUGH THE PERIOD.
* LOW FOR LIGHT SNOW/ICE PELLETS THIS EVENING...AND POSSIBLE
TIMING.
* LOW FOR FREEZING DRIZZLE FOR LATE TONIGHT.
* MEDIUM TO HIGH FOR MVFR CIGS LATE TONIGHT INTO WEDNESDAY
MORNING.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT...CHANCE OF SNOW. MVFR POSSIBLE. STRONG/GUSTY
NORTHWEST WINDS.
* THURSDAY...CHANCE OF FLURRIES. MVFR POSSIBLE. STRONG/GUSTY
NORTHWEST WINDS.
* FRIDAY...SLIGHT CHANCE OF SNOW. MVFR POSSIBLE. WEST/SOUTHWEST
WINDS.
* SATURDAY...CHANCE OF FLURRIES. MVFR POSSIBLE. VERY STRONG/GUSTY
NORTHWEST WINDS.
* SUNDAY...DRY/VFR. WEST/SOUTHWEST WINDS.
* MONDAY...MVFR POSSIBLE. SOUTHWEST WINDS.
&&
.MARINE...
321 AM...ACTIVE PATTERN WILL CONTINUE THROUGH THIS WEEKEND WITH A
PERIOD OF GALES AND HEAVY FREEZING SPRAY WEDNESDAY NIGHT INTO
THURSDAY AND AGAIN FRIDAY NIGHT INTO SATURDAY.
NO SIGNIFICANT CHANGES FROM PREVIOUS FORECAST. LOW PRESSURE OVER
THE DAKOTAS WILL MOVE EAST ACROSS THE NORTHERN LAKES WEDNESDAY
WITH A TRAILING COLD FRONT MOVING ACROSS THE LAKE BY EARLY WED
AFTERNOON. STRONG HIGH PRESSURE WILL BUILD ACROSS THE NORTHERN
LAKES AND UPPER MIDWEST THEN SLIDE SOUTH OF THE LAKES REGION ON
THURSDAY. THE TIGHT GRADIENT COMBINED WITH VERY COLD AIR SPREADING
OVER THE REGION WILL ALLOW GALES TO DEVELOP EITHER LATE WEDNESDAY
AFTERNOON OR EARLY WEDNESDAY EVENING. HOISTED BOTH A GALE WATCH
AND HEAVY FREEZING SPRAY WATCH FOR THIS FIRST EVENT.
ANOTHER LOW WILL MOVE FROM ONTARIO FRIDAY TO THE MID ATLANTIC ON
SATURDAY AS IT DEEPENS SLIGHTLY. AT THE SAME TIME ANOTHER VERY
STRONG ARCTIC HIGH WILL BUILD ACROSS THE NORTHERN PLAINS SATURDAY
AND THEN THE WESTERN LAKES SATURDAY NIGHT. THE COMBINED TIGHT
GRADIENT AND ANOTHER BLAST OF EVEN COLDER AIR WILL LIKELY PUSH
GALES INTO THE MID 40KT RANGE. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742-
LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878...3 PM WEDNESDAY TO 3 PM THURSDAY.
HEAVY FREEZING SPRAY WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-
LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-
LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 PM WEDNESDAY TO 3 PM
THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1156 AM CST Tue Feb 10 2015
.UPDATE...
ISSUED AT 1045 AM CST TUE FEB 10 2015
Updated forecast during mid morning to address the sky cover today.
Low clouds around 1500 ft were clearing quicker over eastern IL
with clearing just east of DEC airport at 1030 am. Low clouds were
also spreading back to the nw across the IL river valley and
currently approaching Galesburg as flow was becoming se nw of IL
river with GBG having se wind 12G16 mph. HRRR model is handling
the coverage of low clouds really well this morning and used it
for afternoon cloud cover trends. HRRR model continues to show low
clouds decreasing from the east, while overspreading rest of Knox
county late this morning, with low clouds lingering through the
afternoon over IL river valley especially from PIA/IL river nw.
Highs in the mid 30s central IL and upper 30s in southeast IL
looks on track this afternoon with lower 30s nw of IL river where
low clouds linger much of the day. Winds to become ese 5-10 mph
this afternoon. 1035 mb Canadian high pressure over ne Ontario was
ridging southward into IL late this morning. Ridge axis to drift
east into the Ohio river valley this evening while a weak 1010 mb
surface low along the ND/SD border tracks east to near the WI/MN
border by midnight tonight. This system to keep the brunt of its
mixed precipitation north of I-88 this afternoon and tonight.
&&
.SHORT TERM...(Today)
ISSUED AT 251 AM CST TUE FEB 10 2015
High pressure ridge just to the northwest of the area will shift
east, through the CWA today. Low level clouds east of the ridge
continue to follow the flow around the high and based on satellite
trends is moving west and southwest early this morning. This, plus
the clear skies across most of Indiana, makes for a complicated
cloud forecast for the day. Believe clouds will hang around most of
the area east of the Illinois river, with mostly clear skies
northwest of the river. Based on timing tools, looks like the
clearing in Ind will move into eastern parts of the CWA first and
then slowly move west into the central part of the state, through
still remaining east of Decatur and Bloomington through about noon.
The clouds could diminish some as well, but this more difficult to
forecast given the strong high pressure. Believe clearing of the
rest of the CWA will occur quickly during the afternoon hours. So,
overall, looking at a partly to mostly sunny sky across the area
today. Winds will be on the light side and variable as the ridge
moves across the area. Temps should be warmer and more around
normal, in the mid to upper 30s.
&&
.LONG TERM...(Tonight through Monday)
ISSUED AT 251 AM CST TUE FEB 10 2015
The main issue for the bulk of the forecast continues to be with the
temperatures. Trough axis currently across the Northwest Territories
of Canada still progged to quickly drop southeast today and sharpen
into a deep trough as a ridge axis builds along the West Coast. The
leading cold front will be passing through the forecast area
Wednesday, although highs in the 30s and 40s will be common.
However, the core of the cold air will begin to arrive during the
evening with the deep trough. 850 mb temperatures dip down to around
-20C early Thursday before the trough quickly shifts east, resulting
in high temperatures in the teens most areas, except lower 20s south
of I-70. Blustery northwest winds likely will gust to over 30 mph at
times, keeping wind chills below zero much of the day.
Stronger surge of cold air will be plunging across the Midwest late
Friday night and Saturday, as a deep closed low drops into the Great
Lakes region. The coldest air, with 850 mb temperatures around -25
to -26C, will be over our area on Saturday, with the GFS and ECMWF
both spreading this Arctic air mass over a large part of the eastern
U.S. (-20C at 850 mb as far southeast as Charleston SC by Sunday
morning). Have lowered high temperatures a couple degrees for
Saturday, with 10-15 degrees common north of I-70, although this may
be a bit conservative. With another day of northwest winds gusting
over 30 mph, persisting into Saturday evening, wind chills will be
close to advisory levels across the northern CWA. Temperatures
Sunday will be about 10 degrees warmer, but still below freezing.
Some respite on tap for Monday, although model trends in the longer
ranges suggest another surge of Arctic air arriving toward the
middle of next week.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 1155 AM CST TUE FEB 10 2015
MVFR clouds with bases of 1.3-2k ft have scattered out at CMI and
DEC during the morning and will scatter out at BMI and SPI between
19Z-21Z and at PIA 21Z-23Z. Broken mid level clouds 10-12k ft over
IA will arrive at PIA around 00Z and along I-55 at 01-02Z and CMI and
DEC at 02-04Z. 1010 mb low pressure along the eastern ND/SD border
to track east to A cold front to track into western Lake Superior
by dawn Wed and then push a cold front east to the IL river early
Wed morning and through DEC/CMI by late Wed morning. MVFR clouds
to occur along and behind this front while light precipitation
stays north of central IL. ESE winds less than 10 kts to become south
tonight and then brisk WNW 10-15 kts with gusts 15-20 kts after
15Z Wed behind cold front.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...07
SHORT TERM...Auten
LONG TERM...Geelhart
AVIATION...07
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
238 PM EST TUE FEB 10 2015
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 1011 AM EST TUE FEB 10 2015
HIGH PRESSURE WILL BRING DRY WEATHER TO THE AREA TODAY AND HIGHS
NEAR NORMAL TODAY AND SLIGHT ABOVE NORMAL WEDNESDAY. HOWEVER AN
ARCTIC FRONT WILL MOVE THROUGH THE AREA WEDNESDAY AFTERNOON AND
EVENING AND BRING SOME CHANCES FOR MIXED PRECIPITATION AND THEN
SNOW WEDNESDAY NIGHT AND THURSDAY ALONG WITH MUCH COLDER AIR.
UPPER TROUGHING WILL KEEP COLDER THAN NORMAL TEMPERATURES IN PLACE
THROUGH AT LEAST THE WEEKEND.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1011 AM EST TUE FEB 10 2015
WESTERN HALF OF THE FORECAST AREA ENJOYING MOSTLY SUNNY SKIES THIS
MORNING WHILE EASTERN COUNTIES REMAIN UNDER STRATUS. CHILLY START
WITH TEMPS RANGING FROM THE HIGH TEENS INTO THE 20S AT 15Z.
FEW CHANGES NECESSARY FOR MORNING UPDATE FOCUSED ON CLOUD COVER
AND IMPACTS TO AFTERNOON HIGHS. STRATUS DECK HAS EXPANDED WESTWARD
ACROSS EASTERN COUNTIES SO FAR THIS MORNING. RAP SHOWING LOW LEVEL
FLOW WILL REMAIN EASTERLY AT LEAST FOR THE NEXT FEW HOURS BEFORE
GRADUALLY VEERING TO THE SOUTHEAST BY AFTERNOON. THE EASTERLY FLOW
SHOULD ENABLE SOME ADDITIONAL WESTWARD EXPANSION TO THE
DECK...POSSIBLY INTO THE INDY METRO BEFORE THE DECK BEGINS TO MIX
OUT AND SHIFT NORTH. HAVE BUMPED UP CLOUD COVER EXTENSIVELY OVER
THE EASTERN COUNTIES INTO THE AFTERNOON...WITH POTENTIAL FOR SKIES
TO REMAIN CLOUDY FOR MUCH OF THE DAY OVER DELAWARE AND RANDOLPH
COUNTIES.
HAVE PULLED HIGHS DOWN AS MUCH AS 5 DEGREES IN THE NORTHEAST WITH
THE EXPECTED CLOUDS...ANTICIPATE PORTIONS OF DELAWARE AND RANDOLPH
COUNTIES MAY NOT GET MUCH WARMER THAN 26 OR 27. REST UNCHANGED...
PREVIOUS DISCUSSION FOLLOWS.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
ISSUED AT 343 AM EST TUE FEB 10 2015
HIGH PRESSURE WILL SHIFT EAST DURING THE NIGHT TONIGHT AND ALLOW FOR
INCREASING CLOUD COVER AND WARM ADVECTION. A FRONTAL SYSTEM WILL
BEGIN TO APPROACH FROM THE WEST BUT THE FORCING FROM THIS SHOULD
REMAIN UPSTREAM OF THE AREA UNTIL DAYTIME ON WEDNESDAY SO SHOULD
REMAIN DRY THROUGH TONIGHT. WEDNESDAY MORNING FRONTOGENESIS REMAINS
WELL WEST OR NORTHWEST OF THE AREA...HOWEVER THERE IS SOME
INDICATION OF ISENTROPIC LIFT AND SATURATION SHOWING UP ACROSS THE
EASTERN COUNTIES IN BOTH THE NAM AND THE ECMWF. THIS COULD BE AN
INDICATION OF JUST ENOUGH LIFT TO PRODUCE SOME LIGHT SHOWERS THERE
SO WILL ADD A SLIGHT CHANCE AT THIS TIME. TEMPERATURE PROFILES
INDICATE THE WARMING ALOFT WILL OUTPACE THAT AT THE SURFACE SO COULD
SEE A FEW HOURS OF SLEET OR SNOW BEFORE THE COLUMN WARMS ENOUGH FOR
RAIN. A COLD FRONT SHOULD MOVE INTO THE AREA DURING THE
AFTERNOON/EVENING AND THUS MUCH OF THE AREA WILL HAVE A SLIGHT
CHANCE FOR SOME PRECIP...WITH WARM ENOUGH TEMPERATURES TO START AS
RAIN IN THE AFTERNOON AND CHANGE TO A MIX OR ALL SNOW IN THE
EVENING.
WEDNESDAY NIGHT HAS THE BEST FORCING OF THE SHORT
TERM...WITH UPPER FORCING COMBINING WITH THE FRONT STILL IN THE
AREA. THERE IS LITTLE MOISTURE TO WORK WITH SO DON/T EXPECT MUCH IN
THE WAY OF ACCUMULATION BUT THINK THE FORCING LOOKS STRONG ENOUGH TO
PRODUCE A COUPLE TENTHS OF AN INCH AND RAISED POPS FROM CONSENSUS
DURING THIS TIME.
THURSDAY HIGH PRESSURE BEGINS TO BUILD BACK IN AND THE FLOW DURING
THIS TIME COULD BE CONDUCIVE FOR SOME LAKE EFFECT. CONTINUED TO
CARRY LOW CHANCES FOR SNOW ACROSS ALL BUT THE WESTERN COUNTIES
THROUGH THE DAY. THURSDAY NIGHT CONTINUED WITH A CHANCE FOR FLURRIES
IN THE NORTHEAST FOR A FEW HOURS WITH THE LAKE FETCH STILL CONDUCIVE
TO PRODUCING A FEW FLAKES IN THAT AREA.
FOR TEMPERATURES GENERALLY STUCK NEAR A CONSENSUS THROUGH WEDNESDAY.
WENT CLOSER TO THE COLDER END OF THE SOLUTION ENVELOPE FOR WEDNESDAY
NIGHT THROUGH THURSDAY NIGHT WITH STRONG COLD ADVECTION BEHIND THE
ARCTIC FRONT.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ISSUED AT 223 PM EST TUE FEB 10 2015
A STRONG COLD FRONT IS SET TO MOVE INTO THE GREAT LAKES AND OHIO
VALLEY ON FRIDAY NIGHT INTO SATURDAY AS THE GFS AND ECMWF BOTH
SUGGEST A DEEP UPPER LOW SINKING OUT OF NORTHERN CANADA BEFORE
DIPPING INTO THE OHIO VALLEY. STRONG DYNAMICS AND VERY COLD AIR IS
EXPECTED IN THE WAKE OF THIS SYSTEM. AHEAD OF THE SYSTEM
PERSISTENT DRY AIR AMID THE NW FLOW IS EXPECTED TO LIMIT
PRECIPITATION CHANCES. ECMWF 850MB TEMPS FALL TO -22C BY SUNDAY
MORNING...BRINGING SOME OF THE COLDEST AIR OF THE SEASON TO
CENTRAL INDIANA.
FORTUNATELY IT APPEARS THE COLD AIR WILL DEPART QUICKLY TO THE EAST
AS THE STRONG LOW PULLS EAST OFF THE COAST AND RIDGING ASSOCIATED
WITH THE ARCTIC HIGH BUILDS ACROSS THE REGION...PROVIDING DRY
WEATHER SUNDAY AND INTO MONDAY. A WARM FRONT WILL THEN APPROACH
THE AREA ON MONDAY NIGHT AND INTO TUESDAY. THUS WILL INCLUDE
CHANCES FOR A PRECIP AT THAT TIME.
&&
.AVIATION /DISCUSSION FOR THE 101800Z TAFS/...
ISSUED AT 1200 PM EST TUE FEB 10 2015
VFR CONDITIONS AREA EXPECTED TO CONTINUE THIS TAF PERIOD AS A
RIDGE OF HIGH PRESSURE IN PLACE OVER INDIANA AND ILLINOIS WILL
SLOWLY PROGRESS EASTWARD.
A WARM FRONT IS EXPECTED TO PUSH ACROSS THE STATE OVERNIGHT AND
TIME HEIGHTS AND FORECAST SOUNDINGS INDICATE SOME UPPER LEVEL
SATURATION. THUS WILL EXPECT SOME ALTOCU CIGS TO PASS OVERNIGHT
WITH THIS FEATURE.
CIGS WILL TREND TO MVFR AFTER 18Z WEDNESDAY AS A QUICK MOVING COLD
FRONT PASSES ACROSS THE AREA FROM THE NORTHWEST AND COLD AIR
ADVECTION RESUMES WITH TRAPPED STRATOCU.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CP/RYAN
NEAR TERM...RYAN
SHORT TERM...CP
LONG TERM....PUMA
AVIATION...JP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1208 PM EST TUE FEB 10 2015
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 1011 AM EST TUE FEB 10 2015
HIGH PRESSURE WILL BRING DRY WEATHER TO THE AREA TODAY AND HIGHS
NEAR NORMAL TODAY AND SLIGHT ABOVE NORMAL WEDNESDAY. HOWEVER AN
ARCTIC FRONT WILL MOVE THROUGH THE AREA WEDNESDAY AFTERNOON AND
EVENING AND BRING SOME CHANCES FOR MIXED PRECIPITATION AND THEN
SNOW WEDNESDAY NIGHT AND THURSDAY ALONG WITH MUCH COLDER AIR.
UPPER TROUGHING WILL KEEP COLDER THAN NORMAL TEMPERATURES IN PLACE
THROUGH AT LEAST THE WEEKEND.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1011 AM EST TUE FEB 10 2015
WESTERN HALF OF THE FORECAST AREA ENJOYING MOSTLY SUNNY SKIES THIS
MORNING WHILE EASTERN COUNTIES REMAIN UNDER STRATUS. CHILLY START
WITH TEMPS RANGING FROM THE HIGH TEENS INTO THE 20S AT 15Z.
FEW CHANGES NECESSARY FOR MORNING UPDATE FOCUSED ON CLOUD COVER
AND IMPACTS TO AFTERNOON HIGHS. STRATUS DECK HAS EXPANDED WESTWARD
ACROSS EASTERN COUNTIES SO FAR THIS MORNING. RAP SHOWING LOW LEVEL
FLOW WILL REMAIN EASTERLY AT LEAST FOR THE NEXT FEW HOURS BEFORE
GRADUALLY VEERING TO THE SOUTHEAST BY AFTERNOON. THE EASTERLY FLOW
SHOULD ENABLE SOME ADDITIONAL WESTWARD EXPANSION TO THE
DECK...POSSIBLY INTO THE INDY METRO BEFORE THE DECK BEGINS TO MIX
OUT AND SHIFT NORTH. HAVE BUMPED UP CLOUD COVER EXTENSIVELY OVER
THE EASTERN COUNTIES INTO THE AFTERNOON...WITH POTENTIAL FOR SKIES
TO REMAIN CLOUDY FOR MUCH OF THE DAY OVER DELAWARE AND RANDOLPH
COUNTIES.
HAVE PULLED HIGHS DOWN AS MUCH AS 5 DEGREES IN THE NORTHEAST WITH
THE EXPECTED CLOUDS...ANTICIPATE PORTIONS OF DELAWARE AND RANDOLPH
COUNTIES MAY NOT GET MUCH WARMER THAN 26 OR 27. REST UNCHANGED...
PREVIOUS DISCUSSION FOLLOWS.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
ISSUED AT 343 AM EST TUE FEB 10 2015
HIGH PRESSURE WILL SHIFT EAST DURING THE NIGHT TONIGHT AND ALLOW FOR
INCREASING CLOUD COVER AND WARM ADVECTION. A FRONTAL SYSTEM WILL
BEGIN TO APPROACH FROM THE WEST BUT THE FORCING FROM THIS SHOULD
REMAIN UPSTREAM OF THE AREA UNTIL DAYTIME ON WEDNESDAY SO SHOULD
REMAIN DRY THROUGH TONIGHT. WEDNESDAY MORNING FRONTOGENESIS REMAINS
WELL WEST OR NORTHWEST OF THE AREA...HOWEVER THERE IS SOME
INDICATION OF ISENTROPIC LIFT AND SATURATION SHOWING UP ACROSS THE
EASTERN COUNTIES IN BOTH THE NAM AND THE ECMWF. THIS COULD BE AN
INDICATION OF JUST ENOUGH LIFT TO PRODUCE SOME LIGHT SHOWERS THERE
SO WILL ADD A SLIGHT CHANCE AT THIS TIME. TEMPERATURE PROFILES
INDICATE THE WARMING ALOFT WILL OUTPACE THAT AT THE SURFACE SO COULD
SEE A FEW HOURS OF SLEET OR SNOW BEFORE THE COLUMN WARMS ENOUGH FOR
RAIN. A COLD FRONT SHOULD MOVE INTO THE AREA DURING THE
AFTERNOON/EVENING AND THUS MUCH OF THE AREA WILL HAVE A SLIGHT
CHANCE FOR SOME PRECIP...WITH WARM ENOUGH TEMPERATURES TO START AS
RAIN IN THE AFTERNOON AND CHANGE TO A MIX OR ALL SNOW IN THE
EVENING.
WEDNESDAY NIGHT HAS THE BEST FORCING OF THE SHORT
TERM...WITH UPPER FORCING COMBINING WITH THE FRONT STILL IN THE
AREA. THERE IS LITTLE MOISTURE TO WORK WITH SO DON/T EXPECT MUCH IN
THE WAY OF ACCUMULATION BUT THINK THE FORCING LOOKS STRONG ENOUGH TO
PRODUCE A COUPLE TENTHS OF AN INCH AND RAISED POPS FROM CONSENSUS
DURING THIS TIME.
THURSDAY HIGH PRESSURE BEGINS TO BUILD BACK IN AND THE FLOW DURING
THIS TIME COULD BE CONDUCIVE FOR SOME LAKE EFFECT. CONTINUED TO
CARRY LOW CHANCES FOR SNOW ACROSS ALL BUT THE WESTERN COUNTIES
THROUGH THE DAY. THURSDAY NIGHT CONTINUED WITH A CHANCE FOR FLURRIES
IN THE NORTHEAST FOR A FEW HOURS WITH THE LAKE FETCH STILL CONDUCIVE
TO PRODUCING A FEW FLAKES IN THAT AREA.
FOR TEMPERATURES GENERALLY STUCK NEAR A CONSENSUS THROUGH WEDNESDAY.
WENT CLOSER TO THE COLDER END OF THE SOLUTION ENVELOPE FOR WEDNESDAY
NIGHT THROUGH THURSDAY NIGHT WITH STRONG COLD ADVECTION BEHIND THE
ARCTIC FRONT.
&&
.LONG TERM /FRIDAY THROUGH MONDAY NIGHT/...
ISSUED AT 343 AM EST TUE FEB 10 2015
ENSEMBLES ARE STILL VERY CONSISTENT WITH DEPICTING COLD FLOW ACROSS
THE GREAT LAKES AND OHIO VALLEY THROUGH THE MAJORITY OF THIS
PERIOD. ARCTIC AIR ASSOCIATED WITH THIS FLOW WILL CONTINUE TO
PROVIDE WELL BELOW NORMAL TEMPERATURES THROUGH AT LEAST EARLY NEXT
WEEK ALONG WITH VERY DRY AIR. A SHORT WAVE WILL PASS THROUGH THE
AREA FRIDAY THROUGH SATURDAY. THE PERSISTENT DRY AND COLD NORTHERLY
FLOW WILL NOT ALLOW MUCH MOISTURE TO BE IN THE AREA AND PRECIP IS
NOT EXPECTED AT THIS TIME AS THIS SYSTEM PASSES. HOWEVER...LAKE
EFFECT FLURRIES OR SNOW SHOWERS WILL BE POSSIBLE ACROSS THE
NORTHEAST PARTS OF THE FORECAST AREA DURING THE DAY SATURDAY.
THEN LATE IN THE PERIOD...MONDAY NIGHT INTO NEXT TUESDAY A SOUTHERN
STREAM SYSTEM APPEARS TO DEVELOP AND ORGANIZE OVER THE TN VALLEY AND
ALONG WITH SLIGHTLY WARMER FLOW TEMPERATURES WILL MODERATE BACK
TOWARD NORMAL FOR THIS TIME OF YEAR. ALSO CHANCES FOR PRECIP LOOK
MORE PROMISING WITH EITHER SNOW...OR POSSIBLY A MIX OF RAIN/SNOW
BEFORE THIS SYSTEM EXITS THE REGION BY TUESDAY NIGHT.
&&
.AVIATION /DISCUSSION FOR THE 101800Z TAFS/...
ISSUED AT 1200 PM EST TUE FEB 10 2015
VFR CONDITIONS AREA EXPECTED TO CONTINUE THIS TAF PERIOD AS A
RIDGE OF HIGH PRESSURE IN PLACE OVER INDIANA AND ILLINOIS WILL
SLOWLY PROGRESS EASTWARD.
A WARM FRONT IS EXPECTED TO PUSH ACROSS THE STATE OVERNIGHT AND
TIME HEIGHTS AND FORECAST SOUNDINGS INDICATE SOME UPPER LEVEL
SATURATION. THUS WILL EXPECT SOME ALTOCU CIGS TO PASS OVERNIGHT
WITH THIS FEATURE.
CIGS WILL TREND TO MVFR AFTER 18Z WEDNESDAY AS A QUICK MOVING COLD
FRONT PASSES ACROSS THE AREA FROM THE NORTHWEST AND COLD AIR
ADVECTION RESUMES WITH TRAPPED STRATOCU.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CP/RYAN
NEAR TERM...RYAN
SHORT TERM...CP
LONG TERM....SMF
AVIATION...JP
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AREA FORECAST DISCUSSION
NWS MARQUETTE MI
353 PM EST TUE FEB 10 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 353 PM EST TUE FEB 10 2015
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A POLAR BRANCH WNW
FLOW ALOFT OVER THE UPPER GREAT LKS BTWN AN ARCTIC BRANCH FARTHER N
IN CANADA AND A SUBTROPICAL BRANCH OVER THE SRN CONUS. SHRTWV
EMBEDDED IN THIS POLAR BRANCH FLOW IS MOVING ESE TOWARD WRN MN...
CAUSING 12HR H3 HGT FALLS UP TO 120M. ACCOMPANYING AREA OF PCPN IS
OVER MN UNDER AREA OF DEEPER MSTR ENHANCED BY UPR DVGC AHEAD OF THIS
FEATURE AS WELL AS WAA/ISENTROPIC ASCENT BEST SHOWN ON THE 290-300K
SFCS /ABOUT H6-75/ AND SPREADING TO THE NE TOWARD THE WRN CWA.
AHEAD OF THIS PCPN...SKIES OVER UPR MI ARE MAINLY CLDY WITH MOIST
LLVL AIRMASS TRAPPED UNDER SHARP INVRN BASE ARND H9. THERE HAS BEEN
SOME PATCHY LIGHT FREEZING DZ IN AREAS OVER THE KEWEENAW/NCENTRAL
WHERE LLVL ESE FLOW UPSLOPES.
MAIN FCST CONCERNS IN THE SHORT TERM ARE FOCUSED ON SN AMOUNTS
ASSOCIATED WITH INCOMING SHRTWV AND GOING HEADLINES.
LATE TODAY/TNGT...AS AREA OF ISENTROPIC ASCENT/UPR DVGC/DEEP LYR
QVECTOR CNVGC IN ADVANCE OF SHRTWV MOVING THRU MN PUSHES INTO THE
CWA...EXPECT SN TO OVERSPREAD THE AREA W-E. MODELS ARE INDICATING
A 9-12 HR PERIOD OF FORCING BEFORE THE ARRIVAL OF SOME DEEP LYR
QVECTOR DVGC/DNVA OVER THE W LATE IN THE WAKE OF THE SHRTWV/SFC LO
MOVING OVER CENTRAL UPR MI/NRN LK SUP BY 12Z WED. BUT SOME LINGERING
DRY AIR JUST ABOVE THE INVRN BASE WL HINDER THE DEVELOPMENT OF
STEADIER PCPN...ESPECIALLY IN AREAS THAT EXPERIENCE A DOWNSLOPE
WIND COMPONENT WITH ONGOING S FLOW...SO THE ACTUAL WINDOW FOR
STEADIER SN WL ACTUALLY BE 6-9 HRS. MODELS INDICATE ABOUT 2.5 G/KG
SPECIFIC HUMIDITY WL BE PRESENT ON THE 290K SFC ARND H7...WHICH
WOULD SUPPORT GOING FCST UP 3 TO 4 INCHES OF SNOW DURING THE 6-9 HR
WINDOW OF STEADY PCPN. ABSENCE OF ANY PHASING WITH THE ARCTIC/
SUBTROPICAL BRANCES AND SHARPER UPR DVGC ASSOCIATED WITH THE JET
CORES IN THOSE BRANCHES AS WELL AS FCST HI THIN DGZ THAT WL LIMIT
SN/WATER RATIOS WL LIMIT SN TOTALS. LATE TNGT...EXPECT THE PCPN OVER
THE W TO DIMINISH FOR AT LEAST A TIME FOLLOWING THE EXIT OF THE DEEP
UPR FORCING AND PASSAGE OF LO PRES TROF ACCOMPANYING SFC LO MOVING
THRU NRN LK SUP. THE INCOMING AIRMASS WL BE INITIALLY TOO WARM TO
SUPPORT LES. GOING HEADLINES APPEAR TO BE IN GOOD SHAPE. DID ADD
LUCE COUNTY TO THE HEADLINE MIX WITH ARND 3 INCHES EXPECTED THERE
BEFORE THE SN DIMINISHES LATER ON WED MRNG.
WED...LINGERING STEADY SN OVER THE ERN CWA SHOULD END IN THE MRNG
WITH THE PASSAGE OF SHRTWV/ACCOMPANYING SFC LO PRES TROF AND EXIT OF
DEEP LYR QVECTOR CNVGC. GUIDANCE THEN SHOWS AN ARCTIC BRANCH SHRTWV
DIGGING SHARPLY TO NEAR WRN LK SUP BY 00Z THU...WITH H85 TEMPS
FALLING TOWARD -21C OVER THE NW CWA BY 00Z THU FOLLOWING ATTENDANT
COLD FROPA. NNW H925 WINDS INCRSG UP TO 30-35KTS IN THE SHARP CYC
FLOW LEFT IN THE WAKE OF THIS DISTURBANCE AND DEEPENING LO PRES
EXITING TO THE E IN THE STRONG CAA WL RESULT IN VERY GUSTY SFC WINDS
THAT WL AT LEAST APRCH ADVY LEVELS AS WELL AS CONSIDERABLE BLSN IN
ADDITION TO THE LES IN EXPOSED AREAS NEAR LK SUP. THE COMBINATION OF
THE SHARP CYC FLOW AS WELL AS SOME DPVA/DEEP LYR QVECTOR CNVGC/
DEEPENING MSTR WITH THE STRONG CAD MAY BRING A PERIOD OF SOME LK
ENHANCED SN LATE IN THE DAY OVER THE W. LATER SHIFTS WL
NEED TO INCLUDE ADDITIONAL HEADLINES FOR AT LEAST AREAS NEAR LK SUP
FOR LATER WED.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 348 PM EST TUE FEB 10 2015
STEADY N TO NNE WINDS WILL ALREADY BE SET UP AT 00Z THURSDAY...WITH
THE SFC LOW OVER NE LAKE HURON. MUCH OF WEDNESDAY NIGHT WILL BE
MARKED BY STRONG WINDS WITH GUSTS ON THE ORDER OF 30-40KTS. THERE IS
A POCKET OF 35-40KT WINDS BETWEEN 925 AND 800MB FROM 00Z-12Z
THURSDAY. THERE WILL DEFINETLY BE A NON-DIURNAL TREND TO THE WINDS.
WINDS WILL REMAIN OUT OF THE N THROUGH 12Z SUNDAY...ALTHOUGH WEAKEN
SIGNIFICANTLY LATE SATURDAY NIGHT/EARLY SUNDAY MONRING. IT WILL BE
AN EXTENDED PERIOD OF LAKE EFFECT SNOW SHOWERS...THAT WHEN
ACCOMPANIED WITH THE WIND AND THE SNOW ALREADY ON THE GROUND...WILL
RESULT IN SHARPLY REDUCED VISIBILITIES. HEADLINES WILL EVENTUALLY BE
POSTED FOR THIS PERIOD TO NOT ONLY HIGHLIGHT THE 2-4IN OF SNOW FROM
WEDNESDAY AFTERNOON THROUGH WEDNESDAY NIGHT...BUT THE BLOWING SNOW
SHARPLY REDUCING VIS. WILL CONTINUE TO HIGHLIGHT THIS PERIOD IN THE
HWO...WITH THE MAIN FOCUS OF THE SNOW AND BLOWING SNOW BEING ALONG
LAKE SUPERIOR...AND MAINLY FROM THE HURON MOUNTAINS THROUGH MUNISING
AND GRAND MARIAS.
BY DAYBREAK THURSDAY THE SFC WILL HAVE SHIFTED TO NY AND THE STRONG
1048-1052MB/30.9IN HIGH WILL HAVE SLIPPED INTO THE DAKOTAS. THE
PRESSURE GRADIENT WILL WEAKEN DURING THE AFTERNOON HOURS AS THE HIGH
WEAKENS SLIGHTLY ACROSS IA.
EXPECT THE SFC RIDGE TO EXTEND DIRECTLY OVER THE CWA 00-06Z
FRIDAY...BRINGING THE LIGHTEST WINDS OF THE PERIOD AND SHIFTING
LINGERING LES OVER E ALGER AND SCHOOLCRAFT/W LUCE COUNTIES FROM LATE
AFTERNOON THROUGH THE EVENING HOURS. OFFSHORE WINDS WILL TAKE HOLD
ACROSS ALL OF N UPPER MI BY 12Z FRIDAY.
QUICK ON THE HEALS OF THIS PAST SYSTEM...THE NEXT SFC LOW OVER THE W
HALF OF ONTARIO AT 12Z FRIDAY SHOULD CROSS N/CENTRAL LAKE SUPERIOR
BY MID DAY...AND DEEPEN OVER E LAKE SUPERIOR/UPPER MI BY 00Z
SATURDAY. A LIMITED PERIOD OF WAA WILL MEAN THAT 850MB TEMPS WILL
ONLY RISE TO AROUND -18C FRIDAY MORNING-EARLY AFTERNOON. AFTER THE
PASSAGE OF THE LOW LOOK FOR THE -20 TO -25C 850MB AIR TO FILTER BACK
IN. UNLIKE THE PAST COUPLE OF EVENTS...FREEZING DRIZZLE ON THE ONSET
WILL NOT BE A CONCERN.
NW WINDS WILL BE PICKING UP ACROSS THE W HALF OF UPPER MY BY AROUND
21Z...AND INCREASE ACROSS THE ENTIRE CWA OVERNIGHT TURNING FROM OUT
OF THE NW TO N AS THE SFC LOW EXITS ACROSS LAKE HURON AND THE COLD
AIR SETTLES IN WITH THE 500MB LOW OVER CENTRAL ONTARIO AT 06Z
SATURDAY SINKING OVER CENTRAL/E UPPER MI AROUND 12Z. -25 TO -35C AIR
WILL BE OVER THE W HALF BY 12Z SATURDAY /COLDEST OFF THE 10/12Z RUN
OF THE GFS/. EXPECT COLD AND BLUSTERY CONDITIONS LATE FRIDAY NIGHT
THROUGH SATURDAY!
AS PREVIOUSLY STATED...THE FIRST WAVE OF LAKE EFFECT AND STRONG
WINDS WEDNESDAY NIGHT AND THURSDAY WILL GIVE A GOOD FEEL TO WHAT
WILL HAPPEN FRIDAY NIGHT INTO SATURDAY. AT THIS POINT EXPECT
CONDITIONS TO BE WORSE THAN THE FIRST WAVE AND THERE WILL LIKELY BE
A PERIOD OF BLIZZARD CONDITIONS FOR THE FAVORED MARQUETTE-MUNISING
STRETCH AND PERSONS WILL LIKELY NEED TO PLAN FOR THE POSSIBILITY OF
M-28 BEING CLOSED.
WIND CHILL READINGS SATURDAY MORNING WILL FALL TO -15 TO -25F
SATURDAY MORNING AS THE STRONG WINDS COMBINE WITH LOWS AROUND 0F.
LOOK FOR SOME MODERATION TO THE VERY COLD AIR ALOFT SUNDAY...BUT
STILL AROUND -20 TO -25C THROUGH THE DAY SUNDAY. THERE IS SOME
DISCREPANCIES IN THE LOCAL WIND SHIFTS ACROSS LAKE SUPERIOR
SUNDAY...BUT THE TREND WILL BE IMPROVING CONDITIONS EITHER WAY AS
THE SFC HIGH SHIFTS OVERHEAD SUNDAY AND EXITS E SUNDAY
AFTERNOON/EVENING. THE NEXT GOOD CHANCE OF SNOW FOR LATE MONDAY
NIGHT/TUESDAY DOESN/T LOOK TOO IMPRESSIVE OFF THE ECMWF...BUT MORE
DYNAMIC OFF THE GFS. A BLENDED MODEL SOLUTION SEEMS REASONABLE AT
THIS POINT...AS THE MAIN CONCERS AND FOCUS FOR THIS FCST PERIOD ARE
RIGHT AT THE BEGINING AND THEN FRIDAY NIGHT THROUGH SATURDAY
MORNING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1229 PM EST TUE FEB 10 2015
IWD...AS AN AREA OF SN MOVES IN BY ABOUT 21Z...EXPECT VFR CONDITIONS
TO DETERIORATE TO IFR DESPITE PREVAILING DOWNSLOPE SSE FLOW. BUT
ONCE THE MAIN AREA OF FORCING SHIFTS TO THE E BY LATE EVNG...MVFR
CONDITIONS SHOULD RETURN WITH THE DOWNSLOPE S WIND COMPONENT. WINDS
WL SHIFT TO THE W FOLLOWING THE PASSAGE OF A LO PRES TROF EARLY ON
WED MRNG. A STRONGER COLD FROPA TOWARD 15Z WL BRING STRONGER NW
WINDS/SOME LES AND A RETURN OF IFR CONDITIONS.
CMX...EXPECT IFR/LIFR CONDITIONS TO PREVAIL THIS AFTN WITH AN
UPSLOPE ESE FLOW AND PERHAPS A BIT OF -FZDZ. LIFR WX CONTINUE THRU
THIS EVNG WITH THE ARRIVAL OF AREA OF STEADIER SN FM THE SW. THERE
IS LIKELY TO BE A BIT OF A LULL LATER TNGT AND SOME MVFR
CONDITIONS...BUT WSHFT TO AN UPSLOPE W DIRECTION ARND 12Z FOLLOWING
A LO PRES TROF PASSAGE SHOULD BRING A RETURN OF IFR CIGS. GUSTY NW
WINDS AND SOME LES/IFR CONDITIONS WL FOLLOW A STRONGER COLD FROPA BY
LATE MRNG.
SAW...EXPECT IFR CONDITIONS TO PERSIST MOST OF THE TIME THRU TNGT.
BEFORE THE MAIN AREA OF SN ARRIVES THIS EVNG...UPSLOPE SE WINDS WL
BRING SOME FOG AND -FZDZ. CONDIIONS ARE LIKELY TO FALL TO LIFR FOR
AT LEAST A TIME DURING THE NGT UNDER THE BAND OF STEADY SN. ONCE
THIS AREA OF PCPN EXITS BY 12Z...CONDITIONS SHOULD RETURN TO MVFR
WITH STRENGTHENING DOWNSLOPE W VEERING NW WIND FOLLOWING LO PRES
TROF PASSAGE/COLD FROPA.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 348 PM EST TUE FEB 10 2015
THE GALE WATCH FOR WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING WILL
BE UPGRADED TO A GALE WARNING. HEAVY FREEZING SPRAY WARNING WILL BE
NEEDED.
A RIDGE STRETCHING FROM JAMES BAY TO THE LOWER GREAT LAKES WILL
SHIFT E ACROSS QUEBEC TONIGHT. MEANWHILE...A TROUGH ACROSS THE UPPER
MS VALLEY WILL MOVE ACROSS LAKE SUPERIOR LATE TONIGHT AND WEDNESDAY
MORNING. THE LOW WILL CONTINUE E ACROSS THE LOWER GREAT LAKES
THROUGH WEDNESDAY NIGHT AS A TROUGH REMAINS ACROSS LOWER MI. A HIGH
ACROSS S CENTRAL CANADA WEDNESDAY WILL MOVE TO THE MID MS VALLEY ON
THURSDAY AND BUILD A RIDGE ACROSS LAKE SUPERIOR LATE THURSDAY INTO
THURSDAY NIGHT. IN BETWEEN THE EXITING LOW AND NEARING HIGH...N
GALES OF 35 TO 45 KNOTS ACROSS CENTRAL AND EASTERN LAKE SUPERIOR
LATE WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING.
LOOK FOR A LOW ACROSS MANITOBA THURSDAY NIGHT TO SINK ACROSS LAKE
SUPERIOR FRIDAY AFTERNOON AND EVENING...AND THE CENTRAL APPALACHIANS
SATURDAY AFTERNOON...WHILE A LARGE HIGH NEARS FROM SOUTH CENTRAL
CANADA AND THE NORTHERN PLAINS. THIS WILL BRING ABOUT ANOTHER ROUND
OF N GALES OF 35 TO 45 KNOTS AND HEAVY FREEZING SPRAY IS POSSIBLE
FRIDAY NIGHT THROUGH SATURDAY...MAINLY OVER CENTRAL AND EASTERN LAKE
SUPERIOR. EXPECT THE HIGH TO DRIFT ACROSS THE UPPER GREAT LAKES ON
SUNDAY...WITH MUCH LIGHTER WINDS TAKING HOLD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY FROM 7 PM EST /6 PM CST/ THIS EVENING TO
7 AM EST /6 AM CST/ WEDNESDAY FOR MIZ001-003>005-010-011-
084.
WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 7 AM EST
WEDNESDAY FOR MIZ006-013-014-085.
WINTER WEATHER ADVISORY UNTIL 4 AM EST /3 AM CST/ WEDNESDAY FOR
MIZ002-009.
WINTER WEATHER ADVISORY FROM 1 AM TO 10 AM EST WEDNESDAY FOR
MIZ007.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 7 PM WEDNESDAY TO 1 PM EST
THURSDAY FOR LSZ267.
GALE WARNING FROM 4 PM WEDNESDAY TO 1 PM EST THURSDAY FOR LSZ267.
HEAVY FREEZING SPRAY WARNING FROM 1 PM WEDNESDAY TO 7 PM EST
THURSDAY FOR LSZ266.
GALE WARNING FROM 1 PM WEDNESDAY TO 4 PM EST THURSDAY FOR LSZ266.
GALE WARNING FROM 1 PM WEDNESDAY TO 1 PM EST THURSDAY FOR LSZ265.
HEAVY FREEZING SPRAY WARNING FROM 1 PM WEDNESDAY TO 1 PM EST
THURSDAY FOR LSZ264.
GALE WARNING FROM 1 PM WEDNESDAY TO 10 AM EST THURSDAY FOR
LSZ264.
HEAVY FREEZING SPRAY WARNING FROM 1 PM WEDNESDAY TO 7 AM EST
THURSDAY FOR LSZ263.
GALE WARNING FROM 1 PM WEDNESDAY TO 7 AM EST THURSDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...KC
MARINE...KF
AREA FORECAST DISCUSSION
NWS DULUTH MN
1220 PM CST TUE FEB 10 2015
.UPDATE...
ISSUED AT 917 AM CST TUE FEB 10 2015
BRIEF UPDATE TO ADJUST FOR TEMPERATURE TRENDS. NO MAJOR CHANGE TO
WX ELEMENT GRIDS OR POPS...FORECAST STILL ON TRACK. HAVE RECEIVED
REPORTS OF PRECIP BEGINNING AS SLEET THEN CHANGING TO SNOW...BUT
SINCE THIS WAS ONLY OBSERVED FOR A BRIEF PERIOD HAVE OMITTED FROM
THE FORECAST FOR NOW. HAVE SOME CONCERN ABOUT LACK OF ICE IN
COLUMN...ESPECIALLY IN SOUTHERN PINE COUNTY WHERE IT LOOKS LIKE
PRECIP COULD FALL AS FREEZING RAIN FOR A TIME THIS AFTERNOON PER
THE RAP MODEL. LATER TODAY /LATE AFTERNOON/ THERE WILL BE A PERIOD
OF DRYING ALOFT IN THE SOUTHWEST PART OF THE CWA /BRAINERD LAKES
REGION/ WHICH MEANS ANY PRECIP THAT FALLS COULD FALL AS FREEZING
RAIN/DRIZZLE. ON THIS UPDATE ADDED A MIX OF FREEZING RAIN AND
SNOW INTO THIS AREA...AND WILL TAKE A BETTER LOOK LATER THIS
MORNING AS THE GUIDANCE ROLLS IN AS TO WHETHER OR NOT THIS COULD
BE CHANGED TO JUST FREEZING DRIZZLE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CST TUE FEB 10 2015
THE FOCUS REMAINS ON THE APPROACHING LOW PRESSURE SYSTEM FROM THE
WEST...CURRENTLY IN THE NORTHERN HIGH PLAINS EARLY THIS
MORNING...WHICH IS EXPECTED TO BRING WIDESPREAD LIGHT TO MODERATE
SNOWFALL TO THE NORTHLAND TODAY AND TONIGHT. THE LATEST MODELS
RUNS DID NOT SIGNIFICANTLY CHANGE...SO THE FORECAST IS STILL FOR
WIDESPREAD SNOWFALL OF 3 TO 5 INCHES. THERE IS INCREASING
CONFIDENCE THAT THE FAR EASTERN COUNTIES IN NW WISCONSIN WILL
REACH AROUND 3 TO 4 INCHES...SO WAS ABLE TO ISSUE WINTER WEATHER
ADVISORIES FOR THOSE COUNTIES. THE WHOLE FORECAST AREA IS NOW
UNDER A WINTER WEATHER ADVISORY.
TODAY AND TONIGHT...A LOW PRESSURE SYSTEM IN THE NORTHERN HIGH
PLAINS WILL MOVE EAST THROUGH THE DAKOTAS TODAY...THEN CUT ACROSS
MINNESOTA AND WISCONSIN TONIGHT. THIS STORM SYSTEM IS EXPECTED TO
BRING A WIDESPREAD 3 TO 5 INCHES OF SNOW TO THE NORTHLAND LATE
THIS MORNING THROUGH TONIGHT AS IT MOVES THROUGH THE REGION. THERE
COULD BE LOCALLY HIGHER AMOUNTS OF UP TO AROUND 6 INCHES ALONG THE
MINNESOTA ARROWHEAD NORTH SHORE DUE TO LAKE AND TERRAIN
ENHANCEMENT FROM THE SE TO SOUTH WINDS. THE SNOW WILL GRADUALLY
TAPER OFF TONIGHT...GENERALLY FROM WEST TO EAST. A STRONG
SHORTWAVE AND COLD FRONT WILL SWEEP ACROSS THE NORTHLAND TONIGHT
IN THE WAKE OF THE PASSING SYSTEM. GUSTY NORTHWEST WINDS WILL
DEVELOP IN THE WAKE OF THE FRONT. MODEL SOUNDINGS INDICATE THE
POTENTIAL FOR WIND GUSTS UP TO AROUND 25 MPH LATE TONIGHT.
THERE IS A VERY LOW THREAT OF FREEZING DRIZZLE AT TIMES DURING THE
PASSAGE OF THIS SYSTEM...BUT OVERALL THE THERMAL PROFILE IN MODEL
SOUNDINGS SUGGESTS SNOW IS THE MOST LIKELY PCPN TYPE. THINK THE
MAIN CONCERN FOR FREEZING DRIZZLE IS FOR THE INITIAL ONSET OF THE
PCPN THIS MORNING BEFORE THERE IS MORE RAPID AND WIDESPREAD
SATURATION ALOFT BY THIS AFTERNOON. THE RAP13 AND NAM12 MODEL
SOUNDINGS OVER THE WESTERN FORECAST AREA ARE INDICATING A LOW
LEVEL SATURATED LAYER WITH TEMPERATURES AS COLD AS -6 TO -8
DEGREES CELSIUS...WITH BORDERLINE CONFIDENCE IN SUFFICIENT ICE
CRYSTAL DEPOSITION FROM ALOFT...BEFORE CLEARLY SUPPORTING ALL SNOW
BY LATE THIS MORNING. AT THIS TIME...KEPT THE FORECAST ALL SNOW
THROUGH TONIGHT...BUT WILL NEED TO KEEP A CLOSE EYE ON THE
FREEZING DRIZZLE THREAT.
IT HAS BEEN A RELATIVELY QUIET WINTER FOR A WHILE AND MANY WEEKS
SINCE THE MAJORITY OF THE FORECAST AREA HAS SEEN A SIGNIFICANT
SNOW SYSTEM SUCH AS EXPECTED FOR TODAY. MOTORISTS MAY BE A LITTLE
UNPREPARED AND RUSTY FOR THIS KIND OF WEATHER.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 330 AM CST TUE FEB 10 2015
THE LOW PRESSURE SYSTEM RESPONSIBLE FOR THE SNOW WILL BE LOCATED
DIRECTLY OVER LAKE SUPERIOR BY 12Z WEDNESDAY. SCATTERED SNOW
SHOWERS WILL LINGER IN THE WAKE OF THE LOW PASSAGE...AS INTENSE
COLD ADVECTION ACCOMPANIES A COLD FRONT THAT WILL MOVE THROUGH THE
REGION. SOME DIURNALLY DRIVEN SNOW SHOWERS OR FLURRIES WILL BE
POSSIBLE FOR MOST AREAS ON WEDNESDAY...WITH SNOW SHOWERS BECOMING
LIKELY ALONG THE GOGEBIC RANGE OF IRON COUNTY BY LATE WEDNESDAY.
WINDS BECOME ALMOST DIRECTLY NORTH ACROSS LAKE SUPERIOR BY 00Z
THURSDAY. LIMITING FACTOR INITIALLY WILL BE FAIRLY LOW INVERSION
HEIGHTS BUT THE INVERSION HEIGHTS DO RISE SOMEWHAT BY WEDNESDAY
NIGHT AND WE SHOULD SEE SOME ACCUMULATION ACROSS THE SOUTH SHORE
AS A RESULT. STILL A LOT OF OPEN WATER ACROSS LAKE SUPERIOR. VERY
COLD AIR WILL SETTLE IN ACROSS THE REGION FOR THE LAST HALF OF THE
WORK WEEK AND INTO THE WEEKEND AS ARCTIC HIGH PRESSURE BUILDS INTO
THE NORTHLAND. BY WEDNESDAY NIGHT...H85 TEMPS WILL BE AS LOW AS
-25C WITH SURFACE TEMPS WELL INTO THE TEENS AND 20S BELOW ZERO.
ANOTHER WEAK SYSTEM WILL BRING THE CHANCE FOR LIGHT SNOW ON
THURSDAY NIGHT AND FRIDAY...FOLLOWED BY ANOTHER COLD FRONT FRIDAY
NIGHT. ANOTHER WEAK LOW PRESSURE SYSTEM WILL MOVE THROUGH THURSDAY
NIGHT INTO FRIDAY...WITH MORE LIGHT SNOW. OVERALL IT LOOKS LIKE A
COLD EXTENDED TIME PERIOD...WITH A COUPLE OPPORTUNITIES FOR SOME
LIGHTER SNOWFALL AMOUNTS. NO MAJOR STORMS ARE EXPECTED DURING THIS
TIME FRAME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1210 PM CST TUE FEB 10 2015
SNOW WITH IFR/LIFR CEILINGS AND VSBYS WILL PREVAIL ACROSS THE
FORECAST AREA THROUGH THE AFTERNOON. CONDITIONS WILL BEGIN TO
GRADUALLY IMPROVE TO MVFR AFTER 00Z FOR KINL/KBRD/KHIB...AND
AFTER 03Z FOR KHYR AS THE SFC LOW EXITS TO THE EAST OVER LAKE
SUPERIOR AND UPPER MICHIGAN. A BATCH OF ARCTIC AIR WILL SURGE INTO
THE REGION LATE TONIGHT THROUGH WEDNESDAY...RESULTING IN NW WINDS
GUSTING TO 30KT...AND LINGERING CLOUDS/FLURRIES.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 16 16 -13 6 / 90 20 10 0
INL 5 9 -25 3 / 100 20 10 0
BRD 11 13 -11 8 / 60 10 10 0
HYR 20 22 -10 7 / 90 20 30 10
ASX 19 23 -5 6 / 100 40 70 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR MNZ011-
012-019>021-037-038.
WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR MNZ010-
018-025-026-033>036.
WI...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR WIZ001-
002-006>008.
WINTER WEATHER ADVISORY UNTIL 3 AM CST WEDNESDAY FOR WIZ003-004-
009.
LS...NONE.
&&
$$
UPDATE...JJM
SHORT TERM...GROCHOCINSKI
LONG TERM...DAP
AVIATION...GRANING
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1154 AM CST TUE FEB 10 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 322 AM CST TUE FEB 10 2015
LOW PRESSURE ACROSS SCNTL SD IS EXPECTED TO CLEAR THE FCST AREA
OF LOW CLOUDS AND FOG BY 15Z THIS AM. FOG PRODUCTION IN THE DENSE
FOG ADVISORY AREA HAS BE BEEN LIMITED BY MIXING FROM STRONG SFC
WINDS AND POOR RADIATION FROM A BATCH OF MID LEVEL CLOUDS ALOFT.
THE RAP...ETAL MODELS INDICATES FAIRLY STRONG WEST WINDS WILL
DEVELOP BY 12Z SCOURING THE AREA OF MOISTURE AND SHUNTING THE FOG
EAST. THUS THE PROBABILITY OF DENSE FOG APPEARS LOW IN ALL SOLNS.
THE RAP WAS THE WARMEST MODEL AND WAS USED FOR THE TEMPERATURE
FORECAST TODAY FOR HIGHS IN THE UPPER 50S TO MID 60S. NORTHWEST
WINDS WILL BE INCREASING TO 15 TO 25 MPH IN THE WAKE OF THE SFC LOW
ACROSS SD. A TANDEM LOW ACROSS ERN MT WILL MOVE INTO CNTL ND THIS
AFTN AND SEND A COLD FRONT TOWARD NRN NEB. THE MODELS SHOW WEAK
CONVERGENCE AROUND THE LEE SIDE OF THE BLACK HILLS AS THE FRONT
APPROACHES AND THIS MIGHT BE ENOUGH FOR SPRINKLES ACROSS NRN
SHERIDAN COUNTY AND WRN CHERRY COUNTY. THE HRRR...GEM REGIONAL AND
RAP SUPPORT THIS RAIN CHANCE ALBEIT NON-MEASURABLE.
NORTHWEST WINDS SHOULD REMAIN STRONG TONIGHT AS AN ARCTIC COLD FRONT
MOVES THROUGH THE FCST AREA. THE MODELS SHOW WIND SPEEDS INCREASING
FROM 06Z ONWARD ACROSS THE NORTH AND H850MB TEMPERATURES FALLING TO
AROUND -7C BY MORNING WHICH MIGHT SUPPORT LOWS IN THE LOWER 20S
NORTH AND WARMER READINGS IN THE MID AND UPPER 20S TO NEAR 30 SOUTH.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 322 AM CST TUE FEB 10 2015
PRIMARY FORECAST CONCERNS FOR THIS PORTION OF THE FORECAST PERIOD
DEAL WITH TEMPERATURES THROUGHOUT...THEN WITH CHANCES FOR SNOW FOR
EARLY NEXT WEEK.
MODELS ARE IN GOOD AGREEMENT FOR MUCH OF THE FORECAST PERIOD WITH
ONLY MINOR DETAILS SEEN TO IMPACT THE FORECAST. THAT BEING
SAID...EVEN SOME MINOR DIFFERENCES COULD HAVE AN IMPACT ON THE
SENSIBLE WEATHER...MAINLY THE CLOUD COVER AND WINDS...WHICH IN TURN
CAN IMPACT THE TEMPERATURE FORECAST.
THE PERIOD BEGINS ON WEDNESDAY...WITH THE UPPER LEVEL SHORTWAVE
TROUGH WHICH IS NOW OVER THE NORTHWEST TERRITORIES DIGGING SOUTH
INTO THE UPPER MISSISSIPPI RIVER VALLEY REGION. THIS WILL PUSH A
GOOD COLD FRONT THROUGH THE REGION BY 12Z WEDNESDAY. THE TRACK OF
THE MAIN PV ANOMALY EMBEDDED IN THE SHORTWAVE STAYS WELL NORTH AND
EAST OF THE LOCAL AREA BUT THIS WILL LIKELY STILL ENHANCE THE
DOWNWARD MOTION/SUBSIDENCE...DRYING AND COLD AIR ADVECTION DURING
THE DAY TO AT LEAST HELP THE LOW LEVEL MIXING AND BRING ABOUT BREEZY
NORTHWEST WINDS. WITH THE COLD AIR ADVECTION BEHIND THE
FRONT...WEDNESDAY WILL BE QUITE A BIT COOLER THAN WHAT HAS BEEN
EXPERIENCED OVER THE PAST FEW DAYS...WITH HIGHS NEAR NORMAL MOST
PLACES. THE MODELS ARE SHOWING SOME WARMING ALOFT BY THE END OF THE
DAY WEDNESDAY WHICH COULD LEAD TO SLIGHTLY WARMER TEMPERATURES OVER
SOUTHWEST NEBRASKA. THE FORECAST WILL KEEP MID 40S FOR THESE AREAS
WITH LOW 30S OVER NORTH CENTRAL NEBRASKA ON WEDNESDAY.
THE SURFACE HIGH BEHIND THE SYSTEM BUILDS SOUTH INTO THE NORTHERN
PLAINS WEDNESDAY NIGHT...THEN INTO THE MISSISSIPPI RIVER VALLEY ON
THURSDAY. WITH THE COLD AIR ASSOCIATED WITH THE SURFACE
HIGH...TEMPERATURES WILL BE FAIRLY COLD WEDNESDAY NIGHT. THE COLDEST
AIR ALOFT WILL REMAIN ACROSS EASTERN NEBRASKA AND AS THOSE LOCATIONS
WILL BE CLOSER TO THE CENTER OF THE HIGH...WINDS WILL BE LIGHTER
WHICH SHOULD PROMOTE BETTER RADIATIONAL COOLING. FURTHER
WEST...RETURN FLOW SOUTHERLY WINDS SET UP AND ALTHOUGH WILL BE
LIGHT...ARE NOT EXPECTED TO COMPLETELY DROP OFF. THESE CONDITIONS
WILL CREATE A DECENT TEMPERATURE GRADIENT ACROSS THE FORECAST
AREA...FROM THE LOW SINGLE DIGITS TO AROUND 20 DEGREES.
FOR THURSDAY...THE NAM IS A BIT QUICKER THAN THE REMAINDER OF THE
MODEL SOLUTIONS WITH A WARM FRONT MOVING INTO NEBRASKA ON THURSDAY.
TIMING OF THIS FRONT WILL MAKE A DIFFERENCE IN TEMPERATURES DURING
THE AFTERNOON AS 850MB TEMPERATURES INCREASE TO AROUND 10C...WHILE
WEST-NORTHWEST FLOW AT THE SURFACE WILL HELP TO ENHANCE THE MIXING
POTENTIAL AND HELP WARM THINGS UP. HOWEVER...IF THE FRONT IS
SLOWER...COOLER TEMPERATURES WILL BE MAINTAINED THROUGH THE DAY. FOR
THE FORECAST...DID INCREASE HIGHS OVER THE WESTERN PART OF THE
FORECAST AREA AS CONFIDENCE IS HIGHER ON A BIT FASTER MOVEMENT AND
WITH A WARM BIAS THAT HAS BEEN SEEN LATELY IN OBSERVATIONS.
BY THIS POINT IN TIME...THE UPPER LEVEL FLOW ACROSS THE CONUS WILL
BE QUITE AMPLIFIED WITH A DEEP TROUGH OVER THE EAST COAST AND A
STRONG RIDGE OVER THE WESTERN CONUS. THIS PUTS THE LOCAL AREA WITHIN
NORTHWEST FLOW WHICH WILL BRING MULTIPLE SHORTWAVE TROUGHS ACROSS
THE AREA THROUGH THE REMAINDER OF THE FORECAST PERIOD. WHILE
MOISTURE WITH THE MAJORITY OF THESE SYSTEMS STAYS WELL NORTH OF THE
AREA TO KEEP THE FORECAST DRY...DESPITE PERIODS OF STRONGER LIFT.
WHAT WILL OCCUR IS LIKELY A BACK AND FORTH TREND FOR TEMPERATURES.
FRIDAY AND SUNDAY LOOK LIKE WARMER DAYS...WHILE SATURDAY AND MONDAY
WILL BE COOLER AS THE AREA WILL SIT IN THE WAKE OF WEAK SYSTEMS WITH
COLD AIR ADVECTION TO WORK WITH.
THE NEXT CHANCES FOR MEASURABLE PRECIPITATION WILL COME ON MONDAY.
THE UPPER LEVEL PATTERN DAMPENS OUT WITH MORE BROAD WEST TO
NORTHWEST FLOW IN PLACE. THE MODELS CONTINUE TO BE IN DECENT
AGREEMENT THIS FAR OUT BRINGING A WEAK SHORTWAVE TROUGH ACROSS
NEBRASKA AND SOUTH DAKOTA. THE MODELS ARE SHOWING A NEARLY COUPLED
RIGHT OVER-TOP OF THE FORECAST AREA WHICH SHOULD LEAD TO STRONGER
LIFT OVER THE AREA. IN ADDITION...DEEP LAYER MOISTURE INCREASES SO
AT THIS TIME WILL CONTINUE WITH MENTION OF PRECIPITATION FOR EARLY
IN THE WEEK. WITH COLD AIR ADVECTION THROUGH THE DAY
MONDAY...SOUNDINGS AND TEMPERATURE PROFILES WOULD INDICATE THE
PRECIPITATION WILL FALL AS SNOW SO ONLY HAVE THAT MENTION IN THE
FORECAST AT THIS TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1153 CST TUE FEB 10 2015
SCATTERED HIGH CLOUDS WILL MOVE IN FROM THE NORTHWEST INTO NORTH
CENTRAL AND SOUTHWEST NEBRASKA. A COLD FRONT WILL PUSH THROUGH
NORTHERN NEBRASKA TONIGHT. STRATUS WILL DEVELOP OVERNIGHT ACROSS
NORTHERN NEBRASKA...INCLUDING KVTN...CREATING MVFR CONDITIONS. WINDS
WILL CONTINUE TO BE OUT OF THE NORTHWEST ACROSS THE REGION AND WILL
BECOME STRONG LATE AFTERNOON INTO THE OVERNIGHT ACROSS NORTH CENTRAL
NEBRASKA WITH GUST REACHING UP TO 30KTS. ACROSS SOUTHWEST NEBRASKA
EXPECT LIGHTER WINDS AND VFR CONDITIONS TO PREVAIL.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...BROOKS
AVIATION...GOMEZ/MASEK
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1149 AM CST TUE FEB 10 2015
.UPDATE...
ISSUED AT 1038 AM CST TUE FEB 10 2015
THE FOG HAS BEEN GRADUALLY LIFTING AND THIS TREND WILL CONTINUE.
THEREFORE...WILL ALLOW THE DENSE FOG ADVISORY TO EXPIRE AT 11 AM.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 417 AM CST TUE FEB 10 2015
BEFORE STATING ANOTHER WORD...WANT TO SAY THAT THE ONGOING DENSE
FOG ADVISORY FOR MOST OF THE NEBRASKA CWA IS STANDING ON
INCREASINGLY-SHAKY GROUND BASED ON IMPROVING TRENDS THE NEXT FEW
HOURS...AND AN EARLY CANCELLATION BEFORE 5AM NEWS TIME IS
PROBABLY A GOOD BET...AS ALTHOUGH LOCALIZED POCKETS OF DENSE FOG
MIGHT STILL EXIST...THEY ARE CERTAINLY NOT LOOKING WIDESPREAD
ENOUGH TO SUPPORT A FORMAL HEADLINE.
ALTHOUGH ANOTHER SOMEWHAT TRICKY SKY COVER/TEMPERATURE FORECAST IS
IN STORE TODAY...THE ONE GLARING DIFFERENCE BETWEEN NOW AND 24
HOURS AGO IS THAT THE LOW STRATUS/FOG SITUATION IS ON A
DIMINISHING/IMPROVING TREND INSTEAD OF A WORSENING ONE...AND THE
ENTIRE AREA IS EXPECTED TO WARM INTO THE 50S/60S TODAY INSTEAD OF
JUST WESTERN COUNTIES. RUNNING WITH THE ASSUMPTION THAT SKIES
OVER THE CWA SHOULD EXHIBIT A FAIRLY EFFICIENT WEST-TO-EAST AND
IN SOME AREAS A NORTH-TO-SOUTH CLEARING TREND THROUGH MID-
DAY...WE SHOULD NOT BE FACING THE PESKY EXTREMELY SHARP INTERFACE
BETWEEN CLOUDY/SUNNY AREAS THAT LINGERED ALL DAY YESTERDAY. THAT
BEING SAID...WITH EASTERN COUNTIES NEAREST HIGHWAY 81 EXPECTED TO
BE LAST TO SEE APPRECIABLE CLEARING...THESE AREAS SHOULD IN THEORY
REMAIN A BIT COOLER...AND ALSO STAND THE BEST POTENTIAL FOR A
MODEST TEMPERATURE BUST OF 5+ DEGREES.
PRECIPITATION-WISE...OTHER THAN ANY LINGERING LIGHT PATCHY DRIZZLE
OUT THERE THIS MORNING...THE VAST MAJORITY OF THE CWA IS EXPECTED
TO REMAIN DRY THROUGH THESE NEXT 24 HOURS AND THE OFFICIAL
FORECAST REMAINS AS SUCH. THAT BEING SAID...AT LEAST ONE RUN OF
THE NCEP 4KM WRF-NMM SUGGESTS THAT SOME ROGUE SPRINKLES/SPITS OF
DRIZZLE AND MAYBE EVEN A FEW FLURRIES CANNOT BE RULED OUT FROM
LATE THIS AFTERNOON INTO TONIGHT...BUT LACK OF CONFIDENCE IN
OCCURRENCE AND DOUBTS ABOUT HOW MUCH OF THIS LIGHT PRECIP WILL
ACTUALLY REACH THE GROUND HAS PRECLUDED ANY FORMAL FORECAST
MENTION AT THIS TIME. THIS WILL BE SOMETHING FOR THE NEXT FEW
SHIFTS TO KEEP AN EYE ON THOUGH.
ALTHOUGH IT IS EXPECTED TO ESSENTIALLY BE A DRY PASSAGE...THE COLD
FRONT PASSING THROUGH TONIGHT IS DECENTLY-STRONG AND WILL FEATURE
A NOTICEABLE INCREASE IN LATE-NIGHT NORTH WIND...AND SET THE STAGE
FOR A ROUGHLY A 20-DEGREE COOL DOWN FOR WEDNESDAY AS DESCRIBED IN
THE LONG TERM BELOW.
AS FOR THE HERE AND NOW AS OF 1030Z/430AM...ALTHOUGH THE VAST
MAJORITY OF THE CWA REMAINS SOCKED UNDER A VERY LOW STRATUS
DECK...SOME MODEST POCKETS OF CLEARING HAVE BEEN NOTED MAINLY IN
PARTS OF KS ZONES AND ALSO THE THAYER COUNTY AREA. MORE
IMPORTANTLY...INCREASING BOUNDARY-LAYER FLOW THAT IS STARTING TO
TURN MORE SOUTHWESTERLY HAS RESULTED IN IMPROVING VISIBILITY
OVERNIGHT. AS OF THIS WRITING...NEARLY ALL AUTOMATED AIRPORT SITES
IN THE CWA ARE REPORTING VISIBILITY OF NOW-WORSE-THAN ONE-HALF
MILE. ACTUAL SURFACE WIND IS AVERAGING SUSTAINED 10-15 MPH IN MOST
AREAS WITH SOME HIGHER GUSTS MAINLY IN NEB ZONES. EARLIER IN THE
NIGHT AN AREA OF MAINLY ELEVATED RADAR RETURNS BRUSHED ACROSS FAR
NORTHERN ZONES BUT IS CURRENTLY FOCUSED OUTSIDE THE AREA FROM
NORTHEAST NEB NORTHWARD. WOULD NOT BE SHOCKED IF A FEW SLEET
PELLETS/SNOW GRAINS FELL FROM THOSE RADAR ECHOES BUT ITS A NON-
ISSUE NOW. LOW TEMPERATURES THIS MORNING ARE ON TRACK TO BOTTOM
OUT BETWEEN 29-35 IN MOST AREAS. IN THE MID-UPPER LEVELS...WATER
VAPOR SATELLITE AND SHORT TERM MODEL DATA CONFIRM A LOW-AMPLITUDE
SHORTWAVE TRACKING EITHER SIDE OF THE NEB/SD BORDER...PROMOTING
THE LIGHT PRECIP TO THE NORTH. THE ASSOCIATED SURFACE LOW WITH
THAT SYSTEM IS AIDING THE TRANSITION TO MORE SOUTH-SOUTHWESTERLY
SURFACE FLOW THAN THE SOUTHEASTERLY THAT PREVAILED 6-12 HOURS AGO.
MEANWHILE FARTHER NORTH...A SOMEWHAT STRONGER MID LEVEL WAVE IS
SLIPPING EAST-SOUTHEAST OUT OF CANADA INTO ND...AND WILL BE THE
DRIVING FORCE BEHIND THE COLD FRONTAL PASSAGE TONIGHT.
LOOKING FORWARD-FORECAST-WISE IN MORE DETAIL AND STARTING WITH
THE DAYTIME HOURS...ALREADY TOUCHED ON IT ABOVE...BUT THE NUMBER 1
CHALLENGE IS TRYING TO PIN DOWN THE DISSIPATION OF LINGERING
MAINLY LIGHT FOG AND ESPECIALLY THE STILL-EXPANSIVE STRATUS DECK.
ALTHOUGH PRONE TO PLENTY OF SITE-SPECIFIC ERROR...HAVE INDICATED A
FAIRLY- STEADY MAINLY WEST-TO-EAST CLEARING TREND THROUGH MID-
DAY...WITH AT LEAST THE WESTERN 2/3 OF THE CWA LIKELY SEEING
PLENTY OF SUN BY NOON OR SO. THE LATEST HRRR LOW CLOUD PRODUCT
WOULD SUGGEST CLEARING COULD BE EVEN MORE RAPID BUT AM A TOUCH
SKEPTICAL OF THAT. COUNTIES NEAR/ALONG THE HIGHWAY 81 CORRIDOR ARE
MOST PRONE TO SEE AT LEAST HALFWAY-DECENT COVERAGE OF LOW CLOUDS
LINGER INTO EARLY AFTERNOON...BUT WHEN ALL IS SAID AND DONE WOULD
BE SURPRISED IF THE ENTIRE CWA DOES NOT CATCH AT LEAST A FEW HOURS
OF SUN TODAY AS LOW LEVEL FLOW CONTINUES TURNING
WESTERLY/NORTHWESTERLY AND HELPS TO ERODE THE LOW CLOUD MASS. AS A
WEAK TROUGH PASSES THROUGH THE AREA...A GRADUAL TRANSITION FROM
SOUTHERLY TO MORE WESTERLY AND EVENTUALLY NORTHWEST BREEZES WILL
OCCUR TODAY. WHILE SUSTAINED SPEEDS THROUGH MOST OF THE DAY SHOULD
ONLY AVERAGE NO MORE THAN 10-15 MPH WITH SLIGHTLY HIGHER GUSTS.
TEMP-WISE...GENERALLY FOLLOWED A BLEND OF SOME OF THE MOST
OPTIMISTIC MODELS TO YIELD UPPER 50S- MID 60S ACROSS THE MAJORITY
OF THE CWA...BUT HEDGED A BIT COOLER IN FAR EASTERN ZONES WITH
MAINLY MID-50S. OF COURSE...IF LOW STRATUS UNEXPECTEDLY HANGS
AROUND LONGER IN THIS AREA...THIS COULD BE A BIT OPTIMISTIC.
OVERALL THOUGH...UPPED HIGHS ONLY 1-2 DEGREES FROM PREVIOUS
FORECAST. AS EARLIER-STATED...ALTHOUGH NOT IN THE OFFICIAL
FORECAST...SUPPOSE A FEW LATE-DAY SPRINKLES CANNOT BE RULED OUT
MAINLY NORTH OF I-80.
TURNING TO THIS EVENING TONIGHT...THE AFOREMENTIONED DAKOTAS
DISTURBANCE WILL TRACK INTO THE GREAT LAKES REGION...AND BE
REINFORCED BY ANOTHER LOBE OF ENERGY DROPPING SOUTHWARD TOWARD
MN/ND OUT OF CANADA. AGAIN...ALTHOUGH SOME VERY LIGHT/SPOTTY
PRECIP CANNOT BE RULED OUT TONIGHT LOCALLY...BY FAR THE MAIN STORY
WILL BE THE PASSAGE OF A FAIRLY HEALTHY COLD FRONT...WITH 850
MILLIBAR TEMPS BY SUNRISE WEDNESDAY PROGGED TO GENERALLY DROP INTO
THE -3 TO -8 C RANGE OVER MOST OF THE CWA. ALTHOUGH NOT OVERLY-
WINDY...THE ARRIVAL OF THIS FRONT WILL BE MARKED BY SEVERAL HOURS
OF SUSTAINED 15-25 MPH NORTH WIND WITH GUSTS UP TO AROUND 30 MPH.
EXCEPT GENERALLY NORTH OF I-80...THE BRUNT OF THESE STRONGER WINDS
WILL NOT KICK IN UNTIL NEAR/AFTER MIDNIGHT. ALTHOUGH NOT
NECESSARILY EXPECTING ANOTHER TOTALLY-SOLID LOW STRATUS DECK
MOVING IN BEHIND THE FRONT...MODELS SUGGEST A COMBINATION OF
PARTLY- MOSTLY CLOUDY SKIES OVERNIGHT BEHIND THE BOUNDARY...WITH
ANY LOWER STRATUS THAT IS PRESENT POSSIBLY EVEN TRYING TO THROW
OUT A FEW SPITS OF DRIZZLE. AGAIN THOUGH...CONFIDENCE JUST TOO LOW
TO "RUIN" THE CURRENTLY DRY FORECAST. TEMP-WISE...LOWS WILL BE A
LITTLE TRICKY AS WELL...AS FAIRLY PRONOUNCED LOW LEVEL COLD AIR
ADVECTION WILL USHER IN COLDER AIR...BUT ITS FULL POTENTIAL MAY BE
MITIGATED A BIT BY THE INFLUENCE OF LOW LEVEL MIXING FROM THE
STEADY WIND AND ALSO CLOUD COVER. BLENDED A FEW MODELS TOGETHER TO
ESSENTIALLY DROP LOWS A FEW DEGREES IN THE NORTH AND BRING THEM UP
VERY SLIGHTLY SOUTH...AIMING FOR A RANGE FROM MID-20S NORTH OF
I-80 TO MID-30S IN KS ZONES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 417 AM CST TUE FEB 10 2015
FLUCTUATING TEMPERATURES AND MOSTLY DRY CONDITIONS WILL CONTINUE
THROUGH THE EXTENDED PERIODS...WITH ONLY A SMALL CHANCE OF SOME
LIGHT SNOW RETURNING NEXT MONDAY OR TUESDAY.
OVERALL...EXPECT NORTHWESTERLY FLOW ALOFT TO BE DOMINANT THROUGH THE
EXTENDED PERIODS AS A RIDGE OF HIGH PRESSURE BUILDS ACROSS THE WEST
COAST AND MULTIPLE LOW PRESSURE SYSTEMS SWING THROUGH THE OHIO RIVER
VALLEY AND UP THE EAST COAST. THIS GENERAL PATTERN IS FORECAST TO
HOLD THROUGH MOST OF THE EXTENDED...WITH AN UPPER LEVEL DISTURBANCE
PUSHING ACROSS BRITISH COLUMBIA ON SUNDAY FORECAST TO DROP INTO THE
PLAINS EARLY NEXT WEEK. WHILE NOT OVERLY MOIST...THIS SYSTEM WILL
BRING THE BEST CHANCE FOR SOME LIGHT SNOWFALL TO THE LOCAL AREA IN
OVER A WEEK.
STARTING OFF WEDNESDAY...EXPECT BREEZY NORTHERLY WINDS TO BE
ADVECTING COOLER AIR FROM THE NORTH THROUGH THE DAY BEHIND AN EARLY
MORNING COLD FRONT. WHILE NOT BITTERLY COLD...THIS AIRMASS WILL BE
IN STARK CONTRAST TO THIS AFTERNOONS ABOVE NORMAL TEMPERATURES....
LIKELY DROPPING AFTERNOON READINGS VERY CLOSE TO CLIMATOLOGY FOR MID
FEBRUARY. WITH THE ASSOCIATED SURFACE HIGH SLIDING SOUTHEAST ACROSS
THE MISSOURI RIVER VALLEY TO START THE DAY ON THURSDAY...EXPECT A
RETURN TO BELOW NORMAL TEMPERATURES TO START THE DAY...WITH SINGLE
DIGITS FORECAST FOR AT LEAST THE NORTHEASTERN HALF OF THE LOCAL AREA
WHERE THE WINDS WILL BE THE LIGHTEST. WHILE THESE COOL MORNING TEMPS
APPEAR TO BE A SURE THING...AFTERNOON TEMPS ARE A BIT TRICKIER AS
THERE COULD BE A SHARP GRADIENT ACROSS THE LOCAL AREA AS WINDS MAY
BEGIN TO SHIFT LATE IN THE DAY IN RESPONSE TO A SURFACE TROUGH
TRACKING EASTWARD FROM COLORADO. THAT SAID...MODEL CONSENSUS KEEPS
THE WINDS GENERALLY SOUTHERLY BEHIND THE DEPARTING HIGH THROUGH THE
PERIOD OF MAXIMUM HEATING...SO KEPT TEMPS ON THE COOLER SIDE ACROSS
OUR LOCAL AREA THURSDAY AFTERNOON.
THEN AS THE SURFACE TROUGH MOVES ACROSS THE HEART OF THE LOCAL AREA
ON FRIDAY...TEMPERATURES SHOULD SHOOT BACK UP WELL ABOVE NORMAL TO
END THE WEEK...ONLY TO BE BROUGHT BACK DOWN OVER THE UPCOMING
WEEKEND AS A BACKDOOR COLD FRONT WORKS ITS WAY WEST...ASSOCIATED
WITH A VIGOROUS LOW PRESSURE SYSTEM ACROSS THE GREAT LAKES REGION.
WHILE THERE IS SOME DISCREPANCY WITH JUST HOW COLD THIS AIRMASS WILL
BE...TEMPERATURES SHOULD DROP OFF SIGNIFICANTLY...WITH BELOW NORMAL
TEMPERATURES FORECAST FOR SATURDAY...AND ONLY A MODEST WARM UP TO
END THE WEEKEND.
STARTING NEXT WEEK...THE FOCUS WILL SHIFT TO A WEST COAST SYSTEM
THAT WILL BRING ANOTHER COLD FRONT ACROSS THE LOCAL AREA LATE MONDAY
OR TUESDAY...BRINGING ENOUGH MOISTURE TO JUSTIFY THE MENTION FOR A
SMALL CHANCE FOR SOME LIGHT SNOWFALL FOR THE TIME BEING.
OVERALL...THIS DOES NOT APPEAR TO BE A VERY MOIST SYSTEM...BUT WITH
VERY COLD TEMPERATURES...WE COULD SEE SOME LIGHT ACCUMULATIONS AS A
RESULT OF HIGH SNOWFALL RATIOS IF MODEL TRENDS HOLD.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1140 AM CST TUE FEB 10 2015
THE FOG HAS LIFTED BUT WILL NEED TO WATCH OUT FOR POSSIBLY MORE
FOG THIS EVENING BASED ON EARLY INDICATIONS FROM A FEW MODELS.
HOWEVER...THE BETTER CHANCE OF FOG THIS EVENING WILL BE EAST OF
KGRI AND KEAR. IN ADDITION...FOG IS TOO UNCERTAIN TO INCLUDE IN
THE TAF AT THIS POINT IN TIME. IF THERE IS FOG THIS
EVENING/TONIGHT IT WOULD BE MOST LIKELY SOMETIME BETWEEN 7 PM AND
1 AM. OVERALL...EXPECT IMPROVING AVIATION CONDITIONS TODAY WITH
THE CLOUDS BREAKING UP AT KEAR FIRST AND THEN SHORTLY THEREAFTER
AT KGRI. BOTH SHOULD SEE PLENTY OF SUN BY EARLY AFTERNOON IN
KEARNEY...AND BY MID AFTERNOON IN GRAND ISLAND. A FRONT WILL BE
TRACKING SOUTH ACROSS THE AREA TODAY TURNING THE WINDS TO
NORTHERLY THIS AFTERNOON. A STRONGER REINFORCING SHOT OF COLDER
AIR WILL COME THROUGH TONIGHT AND WE WILL NOTICE AN INCREASING
NORTH WIND BEGINNING AROUND MIDNIGHT TONIGHT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...WESELY
SHORT TERM...PFANNKUCH
LONG TERM...ROSSI
AVIATION...WESELY
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1044 AM CST TUE FEB 10 2015
.UPDATE...
ISSUED AT 1038 AM CST TUE FEB 10 2015
THE FOG HAS BEEN GRADUALLY LIFTING AND THIS TREND WILL CONTINUE.
THEREFORE...WILL ALLOW THE DENSE FOG ADVISORY TO EXPIRE AT 11 AM.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 417 AM CST TUE FEB 10 2015
BEFORE STATING ANOTHER WORD...WANT TO SAY THAT THE ONGOING DENSE
FOG ADVISORY FOR MOST OF THE NEBRASKA CWA IS STANDING ON
INCREASINGLY-SHAKY GROUND BASED ON IMPROVING TRENDS THE NEXT FEW
HOURS...AND AN EARLY CANCELLATION BEFORE 5AM NEWS TIME IS
PROBABLY A GOOD BET...AS ALTHOUGH LOCALIZED POCKETS OF DENSE FOG
MIGHT STILL EXIST...THEY ARE CERTAINLY NOT LOOKING WIDESPREAD
ENOUGH TO SUPPORT A FORMAL HEADLINE.
ALTHOUGH ANOTHER SOMEWHAT TRICKY SKY COVER/TEMPERATURE FORECAST IS
IN STORE TODAY...THE ONE GLARING DIFFERENCE BETWEEN NOW AND 24
HOURS AGO IS THAT THE LOW STRATUS/FOG SITUATION IS ON A
DIMINISHING/IMPROVING TREND INSTEAD OF A WORSENING ONE...AND THE
ENTIRE AREA IS EXPECTED TO WARM INTO THE 50S/60S TODAY INSTEAD OF
JUST WESTERN COUNTIES. RUNNING WITH THE ASSUMPTION THAT SKIES
OVER THE CWA SHOULD EXHIBIT A FAIRLY EFFICIENT WEST-TO-EAST AND
IN SOME AREAS A NORTH-TO-SOUTH CLEARING TREND THROUGH MID-
DAY...WE SHOULD NOT BE FACING THE PESKY EXTREMELY SHARP INTERFACE
BETWEEN CLOUDY/SUNNY AREAS THAT LINGERED ALL DAY YESTERDAY. THAT
BEING SAID...WITH EASTERN COUNTIES NEAREST HIGHWAY 81 EXPECTED TO
BE LAST TO SEE APPRECIABLE CLEARING...THESE AREAS SHOULD IN THEORY
REMAIN A BIT COOLER...AND ALSO STAND THE BEST POTENTIAL FOR A
MODEST TEMPERATURE BUST OF 5+ DEGREES.
PRECIPITATION-WISE...OTHER THAN ANY LINGERING LIGHT PATCHY DRIZZLE
OUT THERE THIS MORNING...THE VAST MAJORITY OF THE CWA IS EXPECTED
TO REMAIN DRY THROUGH THESE NEXT 24 HOURS AND THE OFFICIAL
FORECAST REMAINS AS SUCH. THAT BEING SAID...AT LEAST ONE RUN OF
THE NCEP 4KM WRF-NMM SUGGESTS THAT SOME ROGUE SPRINKLES/SPITS OF
DRIZZLE AND MAYBE EVEN A FEW FLURRIES CANNOT BE RULED OUT FROM
LATE THIS AFTERNOON INTO TONIGHT...BUT LACK OF CONFIDENCE IN
OCCURRENCE AND DOUBTS ABOUT HOW MUCH OF THIS LIGHT PRECIP WILL
ACTUALLY REACH THE GROUND HAS PRECLUDED ANY FORMAL FORECAST
MENTION AT THIS TIME. THIS WILL BE SOMETHING FOR THE NEXT FEW
SHIFTS TO KEEP AN EYE ON THOUGH.
ALTHOUGH IT IS EXPECTED TO ESSENTIALLY BE A DRY PASSAGE...THE COLD
FRONT PASSING THROUGH TONIGHT IS DECENTLY-STRONG AND WILL FEATURE
A NOTICEABLE INCREASE IN LATE-NIGHT NORTH WIND...AND SET THE STAGE
FOR A ROUGHLY A 20-DEGREE COOL DOWN FOR WEDNESDAY AS DESCRIBED IN
THE LONG TERM BELOW.
AS FOR THE HERE AND NOW AS OF 1030Z/430AM...ALTHOUGH THE VAST
MAJORITY OF THE CWA REMAINS SOCKED UNDER A VERY LOW STRATUS
DECK...SOME MODEST POCKETS OF CLEARING HAVE BEEN NOTED MAINLY IN
PARTS OF KS ZONES AND ALSO THE THAYER COUNTY AREA. MORE
IMPORTANTLY...INCREASING BOUNDARY-LAYER FLOW THAT IS STARTING TO
TURN MORE SOUTHWESTERLY HAS RESULTED IN IMPROVING VISIBILITY
OVERNIGHT. AS OF THIS WRITING...NEARLY ALL AUTOMATED AIRPORT SITES
IN THE CWA ARE REPORTING VISIBILITY OF NOW-WORSE-THAN ONE-HALF
MILE. ACTUAL SURFACE WIND IS AVERAGING SUSTAINED 10-15 MPH IN MOST
AREAS WITH SOME HIGHER GUSTS MAINLY IN NEB ZONES. EARLIER IN THE
NIGHT AN AREA OF MAINLY ELEVATED RADAR RETURNS BRUSHED ACROSS FAR
NORTHERN ZONES BUT IS CURRENTLY FOCUSED OUTSIDE THE AREA FROM
NORTHEAST NEB NORTHWARD. WOULD NOT BE SHOCKED IF A FEW SLEET
PELLETS/SNOW GRAINS FELL FROM THOSE RADAR ECHOES BUT ITS A NON-
ISSUE NOW. LOW TEMPERATURES THIS MORNING ARE ON TRACK TO BOTTOM
OUT BETWEEN 29-35 IN MOST AREAS. IN THE MID-UPPER LEVELS...WATER
VAPOR SATELLITE AND SHORT TERM MODEL DATA CONFIRM A LOW-AMPLITUDE
SHORTWAVE TRACKING EITHER SIDE OF THE NEB/SD BORDER...PROMOTING
THE LIGHT PRECIP TO THE NORTH. THE ASSOCIATED SURFACE LOW WITH
THAT SYSTEM IS AIDING THE TRANSITION TO MORE SOUTH-SOUTHWESTERLY
SURFACE FLOW THAN THE SOUTHEASTERLY THAT PREVAILED 6-12 HOURS AGO.
MEANWHILE FARTHER NORTH...A SOMEWHAT STRONGER MID LEVEL WAVE IS
SLIPPING EAST-SOUTHEAST OUT OF CANADA INTO ND...AND WILL BE THE
DRIVING FORCE BEHIND THE COLD FRONTAL PASSAGE TONIGHT.
LOOKING FORWARD-FORECAST-WISE IN MORE DETAIL AND STARTING WITH
THE DAYTIME HOURS...ALREADY TOUCHED ON IT ABOVE...BUT THE NUMBER 1
CHALLENGE IS TRYING TO PIN DOWN THE DISSIPATION OF LINGERING
MAINLY LIGHT FOG AND ESPECIALLY THE STILL-EXPANSIVE STRATUS DECK.
ALTHOUGH PRONE TO PLENTY OF SITE-SPECIFIC ERROR...HAVE INDICATED A
FAIRLY- STEADY MAINLY WEST-TO-EAST CLEARING TREND THROUGH MID-
DAY...WITH AT LEAST THE WESTERN 2/3 OF THE CWA LIKELY SEEING
PLENTY OF SUN BY NOON OR SO. THE LATEST HRRR LOW CLOUD PRODUCT
WOULD SUGGEST CLEARING COULD BE EVEN MORE RAPID BUT AM A TOUCH
SKEPTICAL OF THAT. COUNTIES NEAR/ALONG THE HIGHWAY 81 CORRIDOR ARE
MOST PRONE TO SEE AT LEAST HALFWAY-DECENT COVERAGE OF LOW CLOUDS
LINGER INTO EARLY AFTERNOON...BUT WHEN ALL IS SAID AND DONE WOULD
BE SURPRISED IF THE ENTIRE CWA DOES NOT CATCH AT LEAST A FEW HOURS
OF SUN TODAY AS LOW LEVEL FLOW CONTINUES TURNING
WESTERLY/NORTHWESTERLY AND HELPS TO ERODE THE LOW CLOUD MASS. AS A
WEAK TROUGH PASSES THROUGH THE AREA...A GRADUAL TRANSITION FROM
SOUTHERLY TO MORE WESTERLY AND EVENTUALLY NORTHWEST BREEZES WILL
OCCUR TODAY. WHILE SUSTAINED SPEEDS THROUGH MOST OF THE DAY SHOULD
ONLY AVERAGE NO MORE THAN 10-15 MPH WITH SLIGHTLY HIGHER GUSTS.
TEMP-WISE...GENERALLY FOLLOWED A BLEND OF SOME OF THE MOST
OPTIMISTIC MODELS TO YIELD UPPER 50S- MID 60S ACROSS THE MAJORITY
OF THE CWA...BUT HEDGED A BIT COOLER IN FAR EASTERN ZONES WITH
MAINLY MID-50S. OF COURSE...IF LOW STRATUS UNEXPECTEDLY HANGS
AROUND LONGER IN THIS AREA...THIS COULD BE A BIT OPTIMISTIC.
OVERALL THOUGH...UPPED HIGHS ONLY 1-2 DEGREES FROM PREVIOUS
FORECAST. AS EARLIER-STATED...ALTHOUGH NOT IN THE OFFICIAL
FORECAST...SUPPOSE A FEW LATE-DAY SPRINKLES CANNOT BE RULED OUT
MAINLY NORTH OF I-80.
TURNING TO THIS EVENING TONIGHT...THE AFOREMENTIONED DAKOTAS
DISTURBANCE WILL TRACK INTO THE GREAT LAKES REGION...AND BE
REINFORCED BY ANOTHER LOBE OF ENERGY DROPPING SOUTHWARD TOWARD
MN/ND OUT OF CANADA. AGAIN...ALTHOUGH SOME VERY LIGHT/SPOTTY
PRECIP CANNOT BE RULED OUT TONIGHT LOCALLY...BY FAR THE MAIN STORY
WILL BE THE PASSAGE OF A FAIRLY HEALTHY COLD FRONT...WITH 850
MILLIBAR TEMPS BY SUNRISE WEDNESDAY PROGGED TO GENERALLY DROP INTO
THE -3 TO -8 C RANGE OVER MOST OF THE CWA. ALTHOUGH NOT OVERLY-
WINDY...THE ARRIVAL OF THIS FRONT WILL BE MARKED BY SEVERAL HOURS
OF SUSTAINED 15-25 MPH NORTH WIND WITH GUSTS UP TO AROUND 30 MPH.
EXCEPT GENERALLY NORTH OF I-80...THE BRUNT OF THESE STRONGER WINDS
WILL NOT KICK IN UNTIL NEAR/AFTER MIDNIGHT. ALTHOUGH NOT
NECESSARILY EXPECTING ANOTHER TOTALLY-SOLID LOW STRATUS DECK
MOVING IN BEHIND THE FRONT...MODELS SUGGEST A COMBINATION OF
PARTLY- MOSTLY CLOUDY SKIES OVERNIGHT BEHIND THE BOUNDARY...WITH
ANY LOWER STRATUS THAT IS PRESENT POSSIBLY EVEN TRYING TO THROW
OUT A FEW SPITS OF DRIZZLE. AGAIN THOUGH...CONFIDENCE JUST TOO LOW
TO "RUIN" THE CURRENTLY DRY FORECAST. TEMP-WISE...LOWS WILL BE A
LITTLE TRICKY AS WELL...AS FAIRLY PRONOUNCED LOW LEVEL COLD AIR
ADVECTION WILL USHER IN COLDER AIR...BUT ITS FULL POTENTIAL MAY BE
MITIGATED A BIT BY THE INFLUENCE OF LOW LEVEL MIXING FROM THE
STEADY WIND AND ALSO CLOUD COVER. BLENDED A FEW MODELS TOGETHER TO
ESSENTIALLY DROP LOWS A FEW DEGREES IN THE NORTH AND BRING THEM UP
VERY SLIGHTLY SOUTH...AIMING FOR A RANGE FROM MID-20S NORTH OF
I-80 TO MID-30S IN KS ZONES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 417 AM CST TUE FEB 10 2015
FLUCTUATING TEMPERATURES AND MOSTLY DRY CONDITIONS WILL CONTINUE
THROUGH THE EXTENDED PERIODS...WITH ONLY A SMALL CHANCE OF SOME
LIGHT SNOW RETURNING NEXT MONDAY OR TUESDAY.
OVERALL...EXPECT NORTHWESTERLY FLOW ALOFT TO BE DOMINANT THROUGH THE
EXTENDED PERIODS AS A RIDGE OF HIGH PRESSURE BUILDS ACROSS THE WEST
COAST AND MULTIPLE LOW PRESSURE SYSTEMS SWING THROUGH THE OHIO RIVER
VALLEY AND UP THE EAST COAST. THIS GENERAL PATTERN IS FORECAST TO
HOLD THROUGH MOST OF THE EXTENDED...WITH AN UPPER LEVEL DISTURBANCE
PUSHING ACROSS BRITISH COLUMBIA ON SUNDAY FORECAST TO DROP INTO THE
PLAINS EARLY NEXT WEEK. WHILE NOT OVERLY MOIST...THIS SYSTEM WILL
BRING THE BEST CHANCE FOR SOME LIGHT SNOWFALL TO THE LOCAL AREA IN
OVER A WEEK.
STARTING OFF WEDNESDAY...EXPECT BREEZY NORTHERLY WINDS TO BE
ADVECTING COOLER AIR FROM THE NORTH THROUGH THE DAY BEHIND AN EARLY
MORNING COLD FRONT. WHILE NOT BITTERLY COLD...THIS AIRMASS WILL BE
IN STARK CONTRAST TO THIS AFTERNOONS ABOVE NORMAL TEMPERATURES....
LIKELY DROPPING AFTERNOON READINGS VERY CLOSE TO CLIMATOLOGY FOR MID
FEBRUARY. WITH THE ASSOCIATED SURFACE HIGH SLIDING SOUTHEAST ACROSS
THE MISSOURI RIVER VALLEY TO START THE DAY ON THURSDAY...EXPECT A
RETURN TO BELOW NORMAL TEMPERATURES TO START THE DAY...WITH SINGLE
DIGITS FORECAST FOR AT LEAST THE NORTHEASTERN HALF OF THE LOCAL AREA
WHERE THE WINDS WILL BE THE LIGHTEST. WHILE THESE COOL MORNING TEMPS
APPEAR TO BE A SURE THING...AFTERNOON TEMPS ARE A BIT TRICKIER AS
THERE COULD BE A SHARP GRADIENT ACROSS THE LOCAL AREA AS WINDS MAY
BEGIN TO SHIFT LATE IN THE DAY IN RESPONSE TO A SURFACE TROUGH
TRACKING EASTWARD FROM COLORADO. THAT SAID...MODEL CONSENSUS KEEPS
THE WINDS GENERALLY SOUTHERLY BEHIND THE DEPARTING HIGH THROUGH THE
PERIOD OF MAXIMUM HEATING...SO KEPT TEMPS ON THE COOLER SIDE ACROSS
OUR LOCAL AREA THURSDAY AFTERNOON.
THEN AS THE SURFACE TROUGH MOVES ACROSS THE HEART OF THE LOCAL AREA
ON FRIDAY...TEMPERATURES SHOULD SHOOT BACK UP WELL ABOVE NORMAL TO
END THE WEEK...ONLY TO BE BROUGHT BACK DOWN OVER THE UPCOMING
WEEKEND AS A BACKDOOR COLD FRONT WORKS ITS WAY WEST...ASSOCIATED
WITH A VIGOROUS LOW PRESSURE SYSTEM ACROSS THE GREAT LAKES REGION.
WHILE THERE IS SOME DISCREPANCY WITH JUST HOW COLD THIS AIRMASS WILL
BE...TEMPERATURES SHOULD DROP OFF SIGNIFICANTLY...WITH BELOW NORMAL
TEMPERATURES FORECAST FOR SATURDAY...AND ONLY A MODEST WARM UP TO
END THE WEEKEND.
STARTING NEXT WEEK...THE FOCUS WILL SHIFT TO A WEST COAST SYSTEM
THAT WILL BRING ANOTHER COLD FRONT ACROSS THE LOCAL AREA LATE MONDAY
OR TUESDAY...BRINGING ENOUGH MOISTURE TO JUSTIFY THE MENTION FOR A
SMALL CHANCE FOR SOME LIGHT SNOWFALL FOR THE TIME BEING.
OVERALL...THIS DOES NOT APPEAR TO BE A VERY MOIST SYSTEM...BUT WITH
VERY COLD TEMPERATURES...WE COULD SEE SOME LIGHT ACCUMULATIONS AS A
RESULT OF HIGH SNOWFALL RATIOS IF MODEL TRENDS HOLD.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 651 AM CST TUE FEB 10 2015
ALTHOUGH AT LEAST A FEW MORE HOURS OF VERY POOR (MAINLY LIFR/IFR)
CEILING/VISIBILITY CONDITIONS ARE EXPECTED AT BOTH TERMINALS
THIS MORNING IN PERSISTENT FOG/STRATUS...A MARKED IMPROVEMENT IS
EXPECTED BY EARLY AFTERNOON AS A RETURN TO WESTERLY LOW-LEVEL
FLOW SCOURS OUT THE FOG AND STRATUS. CONFIDENCE IN THE TIMING
DETAILS IS ADMITTEDLY A BIT SHAKY...AS IT COULD BE A VERY GRADUAL
IMPROVEMENT OVER TIME OR IT COULD BE A VERY ABRUPT
IMPROVEMENT...SO STAY TUNED FOR AMENDMENTS. AT ANY RATE...HAVE
KEAR RETURNING TO VFR BY 18Z AND KGRI 19Z AS A BEST STAB FOR NOW.
AS FOR WIND...SURFACE BREEZES THIS MORNING WILL REMAIN QUITE
STEADY FROM THE SOUTH-SOUTHWEST...WITH GUST POTENTIAL TO AROUND
20KT. AS A TROUGH AXIS/WEAK COLD FRONT PASSES THROUGH DURING THE
DAY...BREEZES WILL DIMINISH A BIT AND TURN MORE WEST-
NORTHWESTERLY. LATE IN THE PERIOD TONIGHT..STRONGER NORTH-
NORTHWEST WIND WILL ARRIVE BEHIND A COLD FRONT WITH GUST POTENTIAL
TO AROUND 25KT. DURING THE FINAL 6 HOURS...ANOTHER ROUND OF
POTENTIAL MVFR OR EVEN IFR CEILING COULD OVERSPREAD THE AREA FROM
THE NORTH...BUT CONFIDENCE IS LOW AND WENT WITH A LOW-END VFR
CEILING AT THIS TIME. LASTLY...WILL CONTINUE A SOMEWHAT MARGINAL
MENTION OF LOW LEVEL WIND SHEAR (LLWS) FOR A FEW MORE HOURS AT
KGRI THIS MORNING TO ACCOUNT FOR A GENERALLY 30KT BULK SHEAR
DIFFERENCE BETWEEN THE SURFACE AND ROUGHLY 1500 FT AGL...THANKS TO
SOUTHWESTERLY WIND TOPPING OUT AROUND 40KT AT THIS LEVEL. HAVE
OMITTED THIS LLWS MENTION FROM KEAR GIVEN THAT BULK SHEAR
DIFFERENCE SHOULD BE LESS LIKELY TO EXCEED 30KT BUT IT WILL STILL
BE CLOSE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...WESELY
SHORT TERM...PFANNKUCH
LONG TERM...ROSSI
AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1234 PM EST TUE FEB 10 2015
.SYNOPSIS...
HIGH PRESSURE BUILDING EASTWARD FROM THE GREAT LAKES AND NORTHERN
ONTARIO WILL PROVIDE DRY AND SEASONABLY COLD WEATHER WEATHER
CONDITIONS ACROSS THE NORTH COUNTRY TODAY THROUGH WEDNESDAY.
PREVAILING LOW CLOUDS WILL GRADUALLY DIMINISH PROVIDING PARTLY
CLOUDY CONDITIONS THIS AFTERNOON THROUGH MUCH OF WEDNESDAY. AN
ALBERTA CLIPPER WILL MOVE EAST SOUTHEASTWARD INTO OUR REGION
DURING THE PRE-DAWN HOURS THURSDAY...WITH PERIODS OF LIGHT SNOW
CONTINUING THROUGHOUT THE DAYLIGHT HOURS THURSDAY INTO EARLY
THURSDAY NIGHT. SOME MINOR TRAVEL IMPACTS ARE POSSIBLE WITH
WIDESPREAD LIGHT SNOW ACCUMULATIONS EXPECTED. NO SIGNIFICANT
PRECIPITATION SYSTEMS ARE EXPECTED THEREAFTER...BUT BITTERLY COLD
AIR WILL BECOME ESTABLISHED ACROSS THE REGION FRIDAY AND
CONTINUING INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1136 AM EST TUESDAY...ONLY REAL CHANGE WITH THIS UPDATE WAS
TO DELAY THE CLEARING BY AN HOUR OR TWO. WIDESPREAD DECK OF
STRATUS REMAINS TRAPPED UNDER THE DEVELOPING SUBSIDENCE INVERSION.
CONTINUING TO SEE SOME REPORTS OF FLURRIES ACROSS NORTHERN NEW
YORK AND VERMONT. BACK EDGE OF CLOUDS HAS NOW CLEARED OTTAWA AND
MOVING SLOWLY BUT SURELY FROM NORTHWEST TO SOUTHEAST AS DRIER AIR
OVER SOUTHERN CANADA GRADUALLY PUSHES SOUTHWARD. RAP LOW LEVEL
MOISTURE FIELDS APPEAR TO HANDLING IT THE BEST AND LARGELY USED
ITS DEPICTION FOR CLOUD TRENDS. THUS EXPECTING CLOUD SHIELD TO
GRADUALLY ERODE AND PUSH SOUTH AND EAST AS WE HEAD INTO THE
AFTERNOON HOURS. THINKING CLEARING SKIES REACH THE SAINT LAWRENCE
VALLEY AND NORTHERN CHAMPLAIN VALLEY AROUND 2 PM...BURLINGTON AREA
AROUND 3 PM...CENTRAL VERMONT 4 PM...AND FINALLY SOUTHERN VERMONT
BY 5 PM. HIGH TEMPERATURES SHOULD STILL REACH THE 20S FOR THE
MOST...EXCEPT SOME UPPER TEENS ACROSS PARTS OF NORTHERN NEW YORK.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
AS OF 321 AM EST TUESDAY...SURFACE RIDGE AXIS BUILDS ACROSS
QUEBEC AND NORTHERN NEW ENGLAND OVERNIGHT TONIGHT. PROVIDED SKIES
BECOME MOSTLY CLEAR AS EXPECTED...SHOULD SET UP A GOOD RADIATIVE
COOLING SETUP WITH LIGHT WINDS AND FRESH SNOW COVER. LOOKING AT
LOWS GENERALLY -8 TO +2F (WARMEST IN THE CHAMPLAIN VALLEY AND FAR
SERN VT)...BUT COULD SEE SOME READINGS IN THE TEENS BELOW ZERO
AROUND KSLK AND THE COLDER HOLLOWS IN VERMONT/S NORTHEAST KINGDOM.
POPS NIL.
SURFACE RIDGE AXIS SHOULD HOLD IN PLACE THROUGHOUT THE DAY
WEDNESDAY FROM MAINE SWWD THROUGH VT/NH AND INTO SERN NY.
MEANWHILE...ALBERTA CLIPPER LOW AND ASSOCIATED MID- LEVEL TROUGH
WILL BE SHIFTING ESEWD ACROSS THE GREAT LAKES REGION BY WEDNESDAY
AFTERNOON. DEVELOPING MID- LEVEL SWLY FLOW IN ADVANCE OF THE
TROUGH AXIS SHOULD YIELD AN INCREASE IN MID TO UPPER CLOUDINESS
FROM W-E ACROSS THE NORTH COUNTRY AS THE DAY PROGRESSES. SFC WINDS
SHOULD REMAIN LIGHT AND NOT EXPECTING ANY PRECIPITATION WITH VERY
DRY PBL CONDITIONS PREVAILING. HIGH TEMPERATURES SHOULD REACH THE
15-20F RANGE IN MOST LOCATIONS.
IT APPEARS THAT AREAS OF LIGHT SNOW WILL DEVELOP EASTWARD ACROSS
THE NORTH COUNTRY IN ASSOCIATED WITH THE CLIPPER SYSTEM DURING
WEDNESDAY NIGHT. SHOULD SEE SNOW BEGIN AROUND MIDNIGHT IN NRN NY
AND DURING THE PRE-DAWN HOURS FOR VERMONT. PRIMARY LOW SHIFTS
SLOWLY EASTWARD ACROSS THE REGION LATE THURSDAY MORNING INTO
THURSDAY AFTERNOON...WITH CONTINUED OVERCAST SKIES AND PERIODS OF
LIGHT SNOW. PRESENT INDICATES FROM 00Z GFS/NAM SUGGEST QPF VALUES
OF 0.15 TO 0.3". GIVEN POTENTIAL FOR GOOD DENDRITE GROWTH PER
MODEL SOUNDINGS...SLR/S AROUND 15:1 WOULD YIELD 2-5" WITH THIS
SYSTEM OF GENERALLY LOW DENSITY SNOWFALL. MAIN IMPACT WOULD BE TO
TRAVEL...WITH MINOR SLOWDOWNS EXPECTED FOR BOTH THE EARLY MORNING
AND EVENING COMMUTES ON THURSDAY.
LOW TEMPS WEDNESDAY NIGHT WILL NOT DROP VERY FAR WITH OVERCAST
CONDITIONS IN PLACE (GENERALLY LOW TO MID TEENS). LIKEWISE...HIGHS
THURSDAY WILL ONLY CLIMB INTO THE LOW 20S FOR MOST
SECTIONS...WHICH WILL PROBABLY BE OUR "WARMEST" DAY FOR A WHILE AS
ARCTIC AIR RETURNS IN THE WAKE OF THE CLIPPER SYSTEM BEGINNING
FRIDAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 320 AM EST MONDAY...DAYS 4 THRU 7 WILL FEATURE DEEP FULL
LATITUDE TROF ACROSS THE EASTERN CONUS WITH SEVERAL COMPACTED
VORTICITIES MOVING ACROSS THE GREAT LAKE AND NE CONUS. THIS LARGE
SCALE SYNOPTIC SETUP WILL FEATURE TEMPS 10 TO 20 DEGREES BLW FOR
THE WEEKEND...AND MOSTLY A DRY FCST. MODEL TRENDS CONT TO SHOW THE
GFS SOLUTION AND ASSOCIATED ENSEMBLE MEMBERS AS THE MOST
AGGRESSIVE WITH S/W ENERGY AND DEVELOPMENT OF STRONG SFC LOW PRES
OFF THE SNE COAST ON FRIDAY...WITH SOME MOISTURE BEING ADVECTED
BACK INTO OUR CWA. HOWEVER...ECMWF IS FURTHER EAST WITH CYCLONE
DEVELOPMENT AND PLACES MUCH LESS DYNAMICS AND MOISTURE ACRS OUR
CWA. WL MENTION CHC POPS ACROSS THE SAINT LAWRENCE VALLEY TO
LIKELY FOR CHAMPLAIN VALLEY AND POINTS EASTWARD ON THURS NIGHT
INTO FRIDAY MORNING. HOWEVER...WITH PWS DROPPING BLW
0.25"...EXPECTING ONLY LIGHT SNOW ACCUMULATIONS...AN ADDITIONAL
DUSTING TO 2 INCHES. PROGGED 85H TEMPS DROP BTWN -22C AND -25C BY
12Z SATURDAY...WITH 925MB TEMPS BTWN -20C TO -24C...SUPPORTING
HIGHS MAINLY 0 TO 10F FOR BOTH FRIDAY AND SATURDAY WITH LOWS -5F
TO -15F. A WIND CHILL ADVISORY WILL BE LIKELY DURING THIS
PERIOD...GIVEN THE EXPECTED PRES GRADIENT ACROSS OUR
CWA...ASSOCIATED WITH DEVELOPING LOW PRESS OFF THE SNE COAST ON
FRIDAY.
NEXT TIGHTLY COMPACTED VORTEX DROPS FROM THE HUDSON BAY REGION ON
SAT INTO SUNDAY AND QUICKLY BECOMES CLOSED OFF AT 7H/5H WITH RAPID
SFC LOW PRES DEVELOPMENT OFF THE SNE COAST. THIS LOOKS TO DEVELOP
TOO FAR EAST TO HAVE SIGNIFICANT PRECIP IMPACTS ACRS OUR CWA...BUT
GUSTY NORTH TO NORTHWEST WINDS WILL RESULT IN STRONG LLVL CAA.
ONCE AGAIN GFS IS MORE AGGRESSIVE WITH ADVECTING LOW LEVEL COLD
AIR ACROSS OUR CWA WITH BOTH 925MB AND 850MB TEMPS NEAR -30C BY
12Z SUNDAY. MEANWHILE...LATEST 00Z EWCMF IS SLIGHTLY WARMER WITH
925MB TO 850MB TEMPS BTWN -24C AND -28C DURING THIS TIME PERIOD.
HAVE NOTED GFS ENSEMBLE 850MB TEMPS ARE 2 TO 3 STD BLW NORMAL
DURING THIS TIME PERIOD...WITH PW VALUES BTWN 1 AND 2 STD BLW
NORMAL...SUPPORTING A COLD AND MAINLY DRY FCST. GIVEN LOW LEVEL
THERMAL PROFILES HIGHS WILL STRUGGLE IN THE -5F TO +5F RANGE FOR
SUNDAY...WITH LOWS SUNDAY NIGHT/MONDAY MORNING BTWN -10F AND -20F.
ALSO...THE COMBINATION OF DEEPENING SFC LOW PRES OVER THE NORTH
ATLANTIC AND BUILDING HIGH PRES WILL CREATE A TIGHT PRES GRADIENT
OVER OUR CWA...WITH GUSTY NORTHWEST WINDS AT 15 TO 25 MPH EXPECTED
WITH THESE COLD TEMPS...CREATING BITTERLY COLD WIND CHILLS. WIND
CHILL ADVISORIES AND WARNINGS WILL BE LIKELY SAT NIGHT THRU
MONDAY. THE ONLY THINK FROM KEEPING TEMPS FROM DROPPING BTWN -20F
AND -30F BY MONDAY MORNING WITH BE THE BRISK WINDS AND SOME MID
LEVEL CLOUDS. THE COLDEST CORE OF AIR SLOWLY MODIFIES BY
MONDAY...WITH WEAK LOW LEVEL WARM ADVECTION DEVELOPING. PROGGED
85H TEMPS WARM TO -20C BY 18Z MONDAY...WITH SFC RIDGE OVERHEAD.
THIS WILL SUPPORT HIGHS BTWN ZERO AND +10F MOST LOCATIONS...WITH
ANOTHER VERY COLD NIGHT EXPECTED ON TUESDAY MORNING. ONCE
AGAIN...GFS AND ECMWF BOTH SHOW CLOUDS INCREASING FROM LOW LEVEL
WARM ADVECTION OVERNIGHT...WILL MAY PREVENT TEMPS FROM COMPLETELY
BOTTOMING OUT. WILL KEEP LOWS MAINLY -5F TO -15F...BUT IF MORE
CLEARING DEVELOPS THAN FORECAST LOWS WILL BE -10F TO -20F WITH
ISOLATED VALUES NEAR -30F...NEK AND SLK.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
THROUGH 18Z WEDNESDAY...LOW CLOUDS STILL HANGING TOUGH THIS
AFTERNOON ACROSS ALL OUR TAF SITES WITH GENERAL MVFR CONDITIONS.
WEAK FLOW AND LIMITED MIXING NOT HELPING US OUT VERY MUCH.
TRACKING CLEARING LINE CURRENTLY MOVING VERY SLOWLY TOWARDS MSS.
ALL SITES SHOULD HAVE VFR CONDITIONS BY 21Z THIS EVENING. IN
ADDITION...LOOK FOR A LIGHT NORTH TO NORTHWEST WIND AT 4 TO 8
KNOTS...TO BECOME LIGHT AND TERRAIN DRIVEN THIS EVENING.
OUTLOOK 18Z WEDNESDAY THROUGH SUNDAY... VFR CONDITIONS WITH
SURFACE HIGH PRESSURE THROUGH 00Z THURS. WEAK CLIPPER SYSTEM WILL
PRODUCE IFR CONDITIONS BETWEEN 03Z THURSDAY TO 18Z THURSDAY WITH
SURFACE VIS VALUES OF 1 TO 3SM AND MVFR CIGS. A BRIEF PERIOD OF
LIFR CONDITIONS WILL BE LIKELY ASSOCIATED WITH THE ACTUAL SFC COLD
FRONT. OTHERWISE...LINGERING SNOW SHOWERS WILL PERSIST INTO FRIDAY
WITH MAINLY MVFR VIS/CIGS IN THE MTNS AND TRENDING VFR ELSEWHERE.
ANOTHER CLIPPER BRINGS MORE MVFR VIS/CIGS ON SATURDAY...SUNDAY
WILL BE VFR.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...MUCCILLI
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...NEILES/TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1138 AM EST TUE FEB 10 2015
.SYNOPSIS...
HIGH PRESSURE BUILDING EASTWARD FROM THE GREAT LAKES AND NORTHERN
ONTARIO WILL PROVIDE DRY AND SEASONABLY COLD WEATHER WEATHER
CONDITIONS ACROSS THE NORTH COUNTRY TODAY THROUGH WEDNESDAY.
PREVAILING LOW CLOUDS WILL GRADUALLY DIMINISH PROVIDING PARTLY
CLOUDY CONDITIONS THIS AFTERNOON THROUGH MUCH OF WEDNESDAY. AN
ALBERTA CLIPPER WILL MOVE EAST SOUTHEASTWARD INTO OUR REGION DURING
THE PRE-DAWN HOURS THURSDAY...WITH PERIODS OF LIGHT SNOW CONTINUING
THROUGHOUT THE DAYLIGHT HOURS THURSDAY INTO EARLY THURSDAY NIGHT.
SOME MINOR TRAVEL IMPACTS ARE POSSIBLE WITH WIDESPREAD LIGHT SNOW
ACCUMULATIONS EXPECTED. NO SIGNIFICANT PRECIPITATION SYSTEMS ARE
EXPECTED THEREAFTER...BUT BITTERLY COLD AIR WILL BECOME ESTABLISHED
ACROSS THE REGION FRIDAY AND CONTINUING INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1136 AM EST TUESDAY...ONLY REAL CHANGE WITH THIS UPDATE WAS
TO DELAY THE CLEARING BY AN HOUR OR TWO. WIDESPREAD DECK OF
STRATUS REMAINS TRAPPED UNDER THE DEVELOPING SUBSIDENCE INVERSION.
CONTINUING TO SEE SOME REPORTS OF FLURRIES ACROSS NORTHERN NEW
YORK AND VERMONT. BACK EDGE OF CLOUDS HAS NOW CLEARED OTTAWA AND
MOVING SLOWLY BUT SURELY FROM NORTHWEST TO SOUTHEAST AS DRIER AIR
OVER SOUTHERN CANADA GRADUALLY PUSHES SOUTHWARD. RAP LOW LEVEL
MOISTURE FIELDS APPEAR TO HANDLING IT THE BEST AND LARGELY USED
ITS DEPICTION FOR CLOUD TRENDS. THUS EXPECTING CLOUD SHIELD TO
GRADUALLY ERODE AND PUSH SOUTH AND EAST AS WE HEAD INTO THE
AFTERNOON HOURS. THINKING CLEARING SKIES REACH THE SAINT LAWRENCE
VALLEY AND NORTHERN CHAMPLAIN VALLEY AROUND 2 PM...BURLINGTON
AREA AROUND 3 PM...CENTRAL VERMONT 4 PM...AND FINALLY SOUTHERN
VERMONT BY 5 PM. HIGH TEMPERATURES SHOULD STILL REACH THE 20S FOR
THE MOST...EXCEPT SOME UPPER TEENS ACROSS PARTS OF NORTHERN NEW
YORK.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
AS OF 321 AM EST TUESDAY...SURFACE RIDGE AXIS BUILDS ACROSS
QUEBEC AND NORTHERN NEW ENGLAND OVERNIGHT TONIGHT. PROVIDED SKIES
BECOME MOSTLY CLEAR AS EXPECTED...SHOULD SET UP A GOOD RADIATIVE
COOLING SETUP WITH LIGHT WINDS AND FRESH SNOW COVER. LOOKING AT
LOWS GENERALLY -8 TO +2F (WARMEST IN THE CHAMPLAIN VALLEY AND FAR
SERN VT)...BUT COULD SEE SOME READINGS IN THE TEENS BELOW ZERO
AROUND KSLK AND THE COLDER HOLLOWS IN VERMONT/S NORTHEAST KINGDOM.
POPS NIL.
SURFACE RIDGE AXIS SHOULD HOLD IN PLACE THROUGHOUT THE DAY
WEDNESDAY FROM MAINE SWWD THROUGH VT/NH AND INTO SERN NY.
MEANWHILE...ALBERTA CLIPPER LOW AND ASSOCIATED MID- LEVEL TROUGH
WILL BE SHIFTING ESEWD ACROSS THE GREAT LAKES REGION BY WEDNESDAY
AFTERNOON. DEVELOPING MID- LEVEL SWLY FLOW IN ADVANCE OF THE
TROUGH AXIS SHOULD YIELD AN INCREASE IN MID TO UPPER CLOUDINESS
FROM W-E ACROSS THE NORTH COUNTRY AS THE DAY PROGRESSES. SFC WINDS
SHOULD REMAIN LIGHT AND NOT EXPECTING ANY PRECIPITATION WITH VERY
DRY PBL CONDITIONS PREVAILING. HIGH TEMPERATURES SHOULD REACH THE
15-20F RANGE IN MOST LOCATIONS.
IT APPEARS THAT AREAS OF LIGHT SNOW WILL DEVELOP EASTWARD ACROSS THE
NORTH COUNTRY IN ASSOCIATED WITH THE CLIPPER SYSTEM DURING WEDNESDAY
NIGHT. SHOULD SEE SNOW BEGIN AROUND MIDNIGHT IN NRN NY AND DURING
THE PRE-DAWN HOURS FOR VERMONT. PRIMARY LOW SHIFTS SLOWLY EASTWARD
ACROSS THE REGION LATE THURSDAY MORNING INTO THURSDAY
AFTERNOON...WITH CONTINUED OVERCAST SKIES AND PERIODS OF LIGHT SNOW.
PRESENT INDICATES FROM 00Z GFS/NAM SUGGEST QPF VALUES OF 0.15 TO
0.3". GIVEN POTENTIAL FOR GOOD DENDRITE GROWTH PER MODEL
SOUNDINGS...SLR/S AROUND 15:1 WOULD YIELD 2-5" WITH THIS SYSTEM OF
GENERALLY LOW DENSITY SNOWFALL. MAIN IMPACT WOULD BE TO
TRAVEL...WITH MINOR SLOWDOWNS EXPECTED FOR BOTH THE EARLY MORNING
AND EVENING COMMUTES ON THURSDAY.
LOW TEMPS WEDNESDAY NIGHT WILL NOT DROP VERY FAR WITH OVERCAST
CONDITIONS IN PLACE (GENERALLY LOW TO MID TEENS). LIKEWISE...HIGHS
THURSDAY WILL ONLY CLIMB INTO THE LOW 20S FOR MOST SECTIONS...WHICH
WILL PROBABLY BE OUR "WARMEST" DAY FOR A WHILE AS ARCTIC AIR RETURNS
IN THE WAKE OF THE CLIPPER SYSTEM BEGINNING FRIDAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 320 AM EST MONDAY...DAYS 4 THRU 7 WILL FEATURE DEEP FULL
LATITUDE TROF ACROSS THE EASTERN CONUS WITH SEVERAL COMPACTED
VORTICITIES MOVING ACROSS THE GREAT LAKE AND NE CONUS. THIS LARGE
SCALE SYNOPTIC SETUP WILL FEATURE TEMPS 10 TO 20 DEGREES BLW FOR
THE WEEKEND...AND MOSTLY A DRY FCST. MODEL TRENDS CONT TO SHOW THE
GFS SOLUTION AND ASSOCIATED ENSEMBLE MEMBERS AS THE MOST
AGGRESSIVE WITH S/W ENERGY AND DEVELOPMENT OF STRONG SFC LOW PRES
OFF THE SNE COAST ON FRIDAY...WITH SOME MOISTURE BEING ADVECTED
BACK INTO OUR CWA. HOWEVER...ECMWF IS FURTHER EAST WITH CYCLONE
DEVELOPMENT AND PLACES MUCH LESS DYNAMICS AND MOISTURE ACRS OUR
CWA. WL MENTION CHC POPS ACROSS THE SAINT LAWRENCE VALLEY TO
LIKELY FOR CHAMPLAIN VALLEY AND POINTS EASTWARD ON THURS NIGHT
INTO FRIDAY MORNING. HOWEVER...WITH PWS DROPPING BLW
0.25"...EXPECTING ONLY LIGHT SNOW ACCUMULATIONS...AN ADDITIONAL
DUSTING TO 2 INCHES. PROGGED 85H TEMPS DROP BTWN -22C AND -25C BY
12Z SATURDAY...WITH 925MB TEMPS BTWN -20C TO -24C...SUPPORTING
HIGHS MAINLY 0 TO 10F FOR BOTH FRIDAY AND SATURDAY WITH LOWS -5F
TO -15F. A WIND CHILL ADVISORY WILL BE LIKELY DURING THIS
PERIOD...GIVEN THE EXPECTED PRES GRADIENT ACROSS OUR
CWA...ASSOCIATED WITH DEVELOPING LOW PRESS OFF THE SNE COAST ON
FRIDAY.
NEXT TIGHTLY COMPACTED VORTEX DROPS FROM THE HUDSON BAY REGION ON
SAT INTO SUNDAY AND QUICKLY BECOMES CLOSED OFF AT 7H/5H WITH RAPID
SFC LOW PRES DEVELOPMENT OFF THE SNE COAST. THIS LOOKS TO DEVELOP
TOO FAR EAST TO HAVE SIGNIFICANT PRECIP IMPACTS ACRS OUR CWA...BUT
GUSTY NORTH TO NORTHWEST WINDS WILL RESULT IN STRONG LLVL CAA.
ONCE AGAIN GFS IS MORE AGGRESSIVE WITH ADVECTING LOW LEVEL COLD
AIR ACROSS OUR CWA WITH BOTH 925MB AND 850MB TEMPS NEAR -30C BY
12Z SUNDAY. MEANWHILE...LATEST 00Z EWCMF IS SLIGHTLY WARMER WITH
925MB TO 850MB TEMPS BTWN -24C AND -28C DURING THIS TIME PERIOD.
HAVE NOTED GFS ENSEMBLE 850MB TEMPS ARE 2 TO 3 STD BLW NORMAL
DURING THIS TIME PERIOD...WITH PW VALUES BTWN 1 AND 2 STD BLW
NORMAL...SUPPORTING A COLD AND MAINLY DRY FCST. GIVEN LOW LEVEL
THERMAL PROFILES HIGHS WILL STRUGGLE IN THE -5F TO +5F RANGE FOR
SUNDAY...WITH LOWS SUNDAY NIGHT/MONDAY MORNING BTWN -10F AND -20F.
ALSO...THE COMBINATION OF DEEPENING SFC LOW PRES OVER THE NORTH
ATLANTIC AND BUILDING HIGH PRES WILL CREATE A TIGHT PRES GRADIENT
OVER OUR CWA...WITH GUSTY NORTHWEST WINDS AT 15 TO 25 MPH EXPECTED
WITH THESE COLD TEMPS...CREATING BITTERLY COLD WIND CHILLS. WIND
CHILL ADVISORIES AND WARNINGS WILL BE LIKELY SAT NIGHT THRU
MONDAY. THE ONLY THINK FROM KEEPING TEMPS FROM DROPPING BTWN -20F
AND -30F BY MONDAY MORNING WITH BE THE BRISK WINDS AND SOME MID
LEVEL CLOUDS. THE COLDEST CORE OF AIR SLOWLY MODIFIES BY
MONDAY...WITH WEAK LOW LEVEL WARM ADVECTION DEVELOPING. PROGGED
85H TEMPS WARM TO -20C BY 18Z MONDAY...WITH SFC RIDGE OVERHEAD.
THIS WILL SUPPORT HIGHS BTWN ZERO AND +10F MOST LOCATIONS...WITH
ANOTHER VERY COLD NIGHT EXPECTED ON TUESDAY MORNING. ONCE
AGAIN...GFS AND ECMWF BOTH SHOW CLOUDS INCREASING FROM LOW LEVEL
WARM ADVECTION OVERNIGHT...WILL MAY PREVENT TEMPS FROM COMPLETELY
BOTTOMING OUT. WILL KEEP LOWS MAINLY -5F TO -15F...BUT IF MORE
CLEARING DEVELOPS THAN FORECAST LOWS WILL BE -10F TO -20F WITH
ISOLATED VALUES NEAR -30F...NEK AND SLK.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
THROUGH 12Z WEDNESDAY...LOW CLOUDS STILL HANGING TOUGH THIS
MORNING ACROSS ALL OUR TAF SITES WITH GENERAL VFR TO MVFR
CONDITIONS. HAVE NOTED IFR CIGS AT SLK. SOUNDINGS ARE TRICKY TODAY
WITH PLENTY OF LOW LEVEL MOISTURE BELOW TEMP INVERSION...ALONG
WITH WEAK FLOW AND LIMITED MIXING. THESE FACTORS COMBINED WITH
WEAK UPSLOPE FLOW...WILL RESULT IN IFR CIGS AT SLK THRU 16Z.
ELSEWHERE...EXPECTING MVFR CIGS TO SLOWLY BECOME VFR BTWN 15Z-17Z
TODAY...AND ALL SITES SHOULD HAVE VFR CONDITIONS BY 21Z THIS
EVENING. IN ADDITION...LOOK FOR A LIGHT NORTH TO NORTHWEST WIND AT
4 TO 8 KNOTS...TO BECOME LIGHT AND TRRN DRIVEN THIS EVENING.
OUTLOOK 12Z WEDNESDAY THROUGH FRIDAY... VFR CONDITIONS WITH
SURFACE HIGH PRESSURE THROUGH 00Z THURS. WEAK CLIPPER SYSTEM WILL
PRODUCE IFR CONDITIONS BETWEEN 03Z THURSDAY TO 18Z THURSDAY WITH
SURFACE VIS VALUES OF 1 TO 3SM AND MVFR CIGS. A BRIEF PERIOD OF
LIFR CONDITIONS WILL BE LIKELY ASSOCIATED WITH THE ACTUAL SFC COLD
FRONT. OTHERWISE...LINGERING SNOW SHOWERS WILL PERSIST INTO FRIDAY
WITH MAINLY MVFR VIS/CIGS IN THE MTNS AND TRENDING VFR ELSEWHERE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...MUCCILLI
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
320 PM CST TUE FEB 10 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 320 PM CST TUE FEB 10 2015
STRONG WINDS AND FALLING TEMPERATURES HIGHLIGHT THE SHORT TERM FORECAST.
AS A OF 20 UTC...A 5MB/3HR PRESSURE RISE BUBBLE WAS ANALYZED OVER
LAKE SAKAKAWEA. THIS FEATURE WILL CONTINUE TO PROPAGATE SOUTHEAST
THROUGH THE LATE AFTERNOON AND EARLY EVENING. WITH 35 TO 40 KTS TO
MIX PER 19 UTC RAP SOUNDINGS...AND ISALLOBARIC FORCING FROM THE
PRESSURE RISES...LOW END WIND ADVISORY CRITERIA GUSTS ARE EXPECTED
INTO THE EARLY EVENING SOUTHWEST AND SOUTH CENTRAL. DID MAINTAIN
A SLIGHT CHANCE FOR SNOW THROUGH THE EVENING AS WELL FOR MUCH OF
WESTERN AND CENTRAL NORTH DAKOTA WITH LIGHT SNOW BEING OBSERVED AT
MULTIPLE SITES ACROSS NORTH DAKOTA INTO SOUTHERN CANADA.
FOR WEDNESDAY...COLD SURFACE HIGH PRESSURE WILL BUILD ACROSS NORTH
DAKOTA. THIS WILL YIELD LITTLE TEMPERATURE RECOVERY FROM MORNING
LOWS WITH CONTINUED COLD AIR ADVECTION THROUGH THE DAY. ADVISORY
LEVEL WIND CHILLS MAY BE POSSIBLE ACROSS THE TURTLE MOUNTAINS BY
LATE AFTERNOON. HOWEVER...WILL FORGO ANY ADVISORY FOR NOW. GIVEN
GOOD AGREEMENT THROUGH THE PERIOD...A BLEND OF THE 12 UTC SUITE
WAS USED FOR MOST FIELDS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 320 PM CST TUE FEB 10 2015
THE LONG TERM WILL BE CHARACTERIZED BY SEVERAL COLD BLASTS AND
OCCASIONAL SNOW CHANCES.
WEDNESDAY NIGHT INTO THURSDAY IS WHEN THE FIRST SUCH COLD BLAST
ENTERS THE REGION. ARCTIC HIGH PRESSURE WILL SETTLE OVER NORTH
DAKOTA THURSDAY MORNING. WITH CLEAR SKIES AND THE MAJORITY OF THE
REGION UNDER AT LEAST A LIGHT BLANKET OF SNOW...TEMPERATURES
SHOULD PLUMMET THURSDAY MORNING INTO THE TEENS AND POSSIBLY 20S
BELOW ZERO EAST OF THE MISSOURI RIVER. SCATTERED LIGHT SNOW MAY
FOLLOW THE HIGH PRESSURE AS AN UPPER LEVEL JET SHOULD BE IN A
FAVORABLE POSITION FOR BROAD SCALE LIFT.
THE NEXT BLAST ARRIVES SATURDAY...WHERE ONCE AGAIN TEMPERATURES
SHOULD ONCE AGAIN FALL INTO THE TEENS BELOW ZERO. AND ONCE AGAIN
SNOW WILL BE POSSIBLE FOLLOWING THE HIGH PRESSURE. HOWEVER...THE
12 UTC GFS AND ECMWF ARE MORE BULLISH WITH THIS EVENT AS A SURFACE
LOW IS FORECAST TO DEVELOP ACROSS EASTERN MONTANA AND SLIDE
SOUTHEAST THROUGH THE DAY SUNDAY. THERE IS THE POTENTIAL FOR MORE
SIGNIFICANT ACCUMULATION WITH THIS EVENT AS THERE APPEARS TO BE
FOCUSED LOW LEVEL ASCENT ALONG WITH THE UPPER LEVEL JET DYNAMICS.
OTHERWISE...THE LONG TERM LOOKS DRY...WITH COLD TEMPERATURES EAST
OF THE MISSOURI AND TEMPERATURES WEST OF THE MISSOURI RIVER
LOOKING RATHER MILD...WITH READINGS IN THE 30S MOST DAYS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 320 PM CST TUE FEB 10 2015
MVFR STRATUS WILL CONTINUE INTO TONIGHT. ISOLATED TO SCATTERED
LIGHT SNOW SHOWERS MAY YIELD BRIEF IFR CONDITIONS THIS AFTERNOON
AND EARLY EVENING. NORTHWEST WINDS WITH GUSTS OF 30 TO 40KTS WILL
INCREASE ACROSS THE AREA THROUGH THE AFTERNOON.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 9 PM CST /8 PM MST/ THIS EVENING FOR
NDZ019>022-033>035-040>046.
WIND ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR NDZ023-025-036-037-
047-048-050-051.
&&
$$
SHORT TERM...AYD
LONG TERM...AJ
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
314 PM EST TUE FEB 10 2015
.SYNOPSIS...
HIGH PRESSURE BUILDS IN TONIGHT. ARCTIC FRONTS CROSSES WEDNESDAY
NIGHT AND AGAIN ON SATURDAY....AND MAYBE EVEN AGAIN NEXT WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
CURRENT SATELLITE IMAGERY SHOWS THE AREA BLANKETED BY LLVL STRATUS
AIDED BY RESIDUAL MOISTURE FROM THE SFC LOW NOW PULLING AWAY FROM THE
MID-ATLANTIC COAST. SOME CLEARING IS BEING OBSERVED IN THE FAR NW
COUNTIES OF OUR CWA AS THE MOISTURE IS SLOWLY ERODED BY DRIER AIR
FROM THE WEST. THE RAP HAS THE BEST HANDLE ON THIS...BUT THATS NOT
SAYING MUCH. MOST GUIDANCE HAS BEEN TERRIBLE WITH RESPECT TO THE
CLEARING OF THE LOW CLOUDS. MOISTURE IS EXPECTED TO HOLD LONGER IN
THE MNTS...WHERE LOW CEILINGS WILL PERSIST UNTIL WED MORNING.
RELATIVELY QUIET NIGHT ON TAP WITH CLOUD COVER CONTINUING TO ERODE
AS THE UPPER RIDGE SETTLES IN. TEMPERATURES WILL REMAIN ON THE
COOL SIDE TONIGHT AS WE DECOUPLE...BUT WAA BEGINS TO KICK FOR
DAYBREAK AND MIXING WILL BRING WEDS TEMPS BACK UP INTO THE 40S FOR
MOST LOCATIONS.
FOR AS LONG AS IT TOOK THE SW RIDGE TO BUILD IN AND DRY THINGS
OUT...IT UNFORTUNATELY WONT STAY LONG. THE FIRST IN A SERIES OF
UPPER LEVEL WAVES WILL ARRIVE EARLY WEDS AFTERNOON...BRINGING
MAINLY CLOUDS BACK TO THE AREA. AS THE UPPER LEVEL WAVE
ARRIVES...IT DEAMPLIFIES AND THE FLOW ALOFT BECOMES MORE ZONAL.
STILL...SOME WEAK MID-LEVEL CONVERGENCE EXISTS AHEAD OF THE FIRST
WAVE AND MODELS HAVE CONSISTENTLY INCLUDED QPF WITH LIGHT SHOWERS
WEDS EVENING. NOT SOLD ON THE IDEA...BUT WITH THIS FEATURE EVEN
RESOLVED IN THE COARSER SUITE OF MODELS...THOUGHT IS WAS PRUDENT
TO INTRODUCE SLGHT CHC POPS.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
ACTIVE AND COLD WEATHER PATTERN REMAINS IN THE SHORT TERM AS A
BARRAGE OF UPPER LEVEL WAVES WILL REINFORCE THE MEAN TROF IN THE
EAST. ANOTHER WEAK WAVE WILL PASS JUST NORTH OF THE FORECAST AREA
WEDS NIGHT AND AGAIN WILL DEAMPLIFY AS ON APPROACH. THIS
DEAMPLIFICATION IS DUE TO THE THIRD AND BY FAR MOST VIGOROUS WAVE
DROPPING IN QUICKLY BEHIND IT. EXPECT LIGHT RAIN CHANGING OVER TO
LIGHT SNOW FOR MAINLY NRN PORTIONS OF THE CWA THROUGH THE PRE-DAWN
HOURS THURS.
AROUND DAWN THURS...CONDITIONS WILL DETERIORATE VERY QUICKLY. AS
AN AMPLIFYING TROF DROPS THROUGH THE WRN GREAT LAKES AND TRIES TO
CLOSE OFF AT 500MB. THIS WILL SEND A A VIGOROUS WAVE THROUGH THE
FORECAST AREA...USHERING IN A COLD FRONT WITH A VASTLY DIFFERENT
AIR MASS BEHIND IT. TEMPERATURES WILL FOLLOW A NON-DIURNAL CURVE
WITH THURS HIGHS MORE THAN LIKELY REALIZED NEAR SUNRISE.
ORIENTED ALONG THE COLD FRONT...SNOW SHOWERS WILL OVERTAKE THE
REGION FROM W TO E QUICKLY DURING THE DAYLIGHT HOURS THURS. BEHIND
THE COLD FRONT...850MB TEMPS WILL DROP SHARPLY INTO THE -10 TO
-15C RANGE ALLOWING CRYSTAL GROWTH TO BE MAXIMIZED. WITH LAPSE
RATES STEEPENING...CONVECTIVE SNOW SQUALLS WILL PERSIST THROUGH THURS
EVENING. THE BTV SNOW SQUALL PARAMETER DRIVEN BY THE 12Z NAM DATA
SHOWS A BULLSEYE OF GREATER THAN 4 FOR MUCH OF THE AFTERNOON
THURS...FURTHER DIAGNOSING A PRIME SET UP FOR SNOW SQUALLS TO
EXIST.
MOISTURE IS DRIVEN INTO THE MOUNTAINS THROUGH THURS NIGHT...AND
SNOW SHOWERS SHOULD PERSIST THERE THROUGH MIDNIGHT THURS.
ELSEWHERE...THE MOISTURE QUICKLY DRIES UP...BUT THE AIRMASS IS
COLD ENOUGH THAT LIGHT SNOW SHOWERS OR FLURRIES COULD PERSIST
THROUGH LATE THURS EVENING.
EXPECT MOUNTAINOUS LOCATIONS TO BE IN THE SINGLE DIGITS TO BELOW
ZERO...AS WELL AS SINGLE DIGITS IN SOUTHEAST OHIO FRIDAY MORNING.
ADDING TO THIS IS THE STRONG...GUSTY WINDS THAT WILL DRIVE WIND
CHILLS TO NEAR 0 ACROSS THE LOWLANDS AND WELL BELOW 0 IN THE
MOUNTAINS. STILL EXPECTING WIND CHILL ADVISORY CRITERIA TO BE MET
ACROSS MUCH OF THE MOUNTAINOUS COUNTIES AND PARTS OF NORTHERN WV.
WILL CONTINUE TO HIGHLIGHT IN THE HWO.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
MEAN TROF PERSISTS ACROSS THE ERN CONUS THROUGH THE EXTENDED
PERIOD KEEPING A PROLONGED COLD AND DISTURBED WEATHER PATTERN.
BRIEF SFC HIGH FRI WILL BE FOLLOWED QUICKLY BY YET ANOTHER VERY
STRONG CLOSED UPPER LOW THIS WEEKEND. THIS WILL ONCE AGAIN
REINFORCE THE COLD AIR...BRINGING THE COLDEST TEMPERATURES OF THE
WEEK TO OUR AREA. MORE LIGHT SNOW IS EXPECTED THROUGH THE
WEEKEND...BUT THE MAIN STORYLINE WILL BE THE COLD TEMPERATURES.
NEXT WEEK BEGINS WITH A VERY BRIEF SPELL OF ZONAL FLOW ALOFT AND
TEMPERATURE MODERATION BEFORE YET ANOTHER INTRUSION OF ARCTIC AIR.
MAINLY FOLLOW WPC FOR WEATHER VARIABLES IN THE EXTENDED...WITH
CONSIDERABLE MODEL AGREEMENT BETWEEN THE GFS/ECMWF.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
IFR CEILINGS CONTINUE AT MOUNTAIN SITES WITH LITTLE OR NO
IMPROVEMENT EXPECTED THIS AFTERNOON. CONDITIONS WILL DETERIORATE
AGAIN AT BOTH SITES OVERNIGHT. REMAINING TERMINALS HAVE IMPROVED TO
MVFR/MOSTLY VFR CEILINGS AS DRY AIR INTRUDES LOW LEVELS. LOW LAND
SITES ARE EXPECTED TO DROP BACK TO MOSTLY MVFR CONDITIONS AT TIMES
AS TEMPERATURES DECREASE OVERNIGHT. ALL TERMINAL SITES WILL SEE
GRADUAL IMPROVEMENT AS FLOW BECOMES SW WITH SURFACE HIGH PRESSURE IN
PLACE.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIO: TIMING OF IMPROVEMENT MAY VARY. MVFR CIGS MAY
NOT MATERIALIZE TONIGHT. IFR FOG IN THE MOUNTAINS OVERNIGHT
TONIGHT MAY NOT HAPPEN EITHER.
AFTER 18Z WEDNESDAY...
IFR IN THE MOUNTAINOUS COUNTIES IN SNOW SHOWERS ON THURSDAY AND
AGAIN SATURDAY AFTERNOON...EACH IN THE WAKE OF ARCTIC FRONTS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TAX
NEAR TERM...TAX
SHORT TERM...TAX
LONG TERM...TAX
AVIATION...RG
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
132 PM EST TUE FEB 10 2015
.SYNOPSIS...
DRIER AIR GRADUALLY PUSHES SOUTH TODAY...AHEAD OF HIGH PRESSURE
BUILDING IN TONIGHT. ARCTIC FRONTS CROSS WEDNESDAY NIGHT AND AGAIN
ON SATURDAY....AND MAYBE EVEN AGAIN NEXT WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
CURRENT SATELLITE IMAGERY SHOWS THE AREA BLANKETED BY LLVL STRATUS
AIDED BY RESIDUAL MOISTURE FROM THE SFC LOW NOW PULLING AWAY FROM THE
MID-ATLANTIC COAST. SOME CLEARING IS BEING OBSERVED IN THE FAR NW
COUNTIES OF OUR CWA AS THE MOISTURE IS SLOWLY ERODED BY DRIER AIR
FROM THE WEST. THE RAP HAS A PRETTY GOOD HANDLE ON THIS AND WILL
BE FOLLOWED FOR THIS TREND THROUGH THE EVENING. MOISTURE WILL HOLD
LONGER IN THE MNTS WHERE EARLIER DRIZZLE AND FOG WERE OBSERVED.
RELATIVELY QUIET NIGHT ON TAP WITH CLOUD COVER CONTINUING TO ERODE
AS THE UPPER RIDGE SETTLES IN. TEMPERATURES WILL REMAIN ON THE
COOL SIDE TONIGHT AS WE DECOUPLE...BUT WAA BEGINS TO KICK FOR
DAYBREAK AND MIXING WILL BRING WEDS TEMPS BACK UP INTO THE 40S FOR
MOST LOCATIONS.
FOR AS LONG AS IT TOOK THE SW RIDGE TO BUILD IN AND DRY THINGS
OUT...IT UNFORTUNATELY WONT STAY LONG. THE FIRST IN A SERIES OF
UPPER LEVEL WAVES WILL ARRIVE EARLY WEDS AFTERNOON...BRINGING
MAINLY CLOUDS BACK TO THE AREA. AS THE UPPER LEVEL WAVE
ARRIVES...IT DEAMPLIFIES AND THE FLOW ALOFT BECOMES MORE ZONAL.
STILL...SOME WEAK MID-LEVEL CONVERGENCE EXISTS AHEAD OF THE FIRST
WAVE AND MODELS HAVE CONSISTENTLY INCLUDED QPF WITH LIGHT SHOWERS
WEDS EVENING. NOT SOLD ON THE IDEA...BUT WITH THIS FEATURE EVEN
RESOLVED IN THE COARSER SUITE OF MODELS...THOUGHT IS WAS PRUDENT
TO INTRODUCE SLGHT CHC POPS.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
ACTIVE AND COLD WEATHER PATTERN REMAINS IN THE SHORT TERM AS A
BARRAGE OF UPPER LEVEL WAVES WILL REINFORCE THE MEAN TROF IN THE
EAST. ANOTHER WEAK WAVE WILL PASS JUST NORTH OF THE FORECAST AREA
WEDS NIGHT AND AGAIN WILL DEAMPLIFY AS ON APPROACH. THIS
DEAMPLIFICATION IS DUE TO THE THIRD AND BY FAR MOST VIGOROUS WAVE
DROPPING IN QUICKLY BEHIND IT. EXPECT LIGHT RAIN CHANGING OVER TO
LIGHT SNOW FOR MAINLY NRN PORTIONS OF THE CWA THROUGH THE PRE-DAWN
HOURS THURS.
AROUND DAWN THURS...CONDITIONS WILL DETERIORATE VERY QUICKLY. AS
AN AMPLIFYING TROF DROPS THROUGH THE WRN GREAT LAKES AND TRIES TO
CLOSE OFF AT 500MB. THIS WILL SEND A A VIGOROUS WAVE THROUGH THE
FORECAST AREA...USHERING IN A COLD FRONT WITH A VASTLY DIFFERENT
AIR MASS BEHIND IT. TEMPERATURES WILL FOLLOW A NON-DIURNAL CURVE
WITH THURS HIGHS MORE THAN LIKELY REALIZED NEAR SUNRISE.
ORIENTED ALONG THE COLD FRONT...SNOW SHOWERS WILL OVERTAKE THE
REGION FROM W TO E QUICKLY DURING THE DAYLIGHT HOURS THURS. BEHIND
THE COLD FRONT...850MB TEMPS WILL DROP SHARPLY INTO THE -10 TO
-15C RANGE ALLOWING CRYSTAL GROWTH TO BE MAXIMIZED. WITH LAPSE
RATES STEEPENING...CONVECTIVE SNOW SQUALLS WILL PERSIST THROUGH THURS
EVENING. THE BTV SNOW SQUALL PARAMETER DRIVEN BY THE 12Z NAM DATA
SHOWS A BULLSEYE OF GREATER THAN 4 FOR MUCH OF THE AFTERNOON
THURS...FURTHER DIAGNOSING A PRIME SET UP FOR SNOW SQUALLS TO
EXIST.
MOISTURE IS DRIVEN INTO THE MOUNTAINS THROUGH THURS NIGHT...AND
SNOW SHOWERS SHOULD PERSIST THERE THROUGH MIDNIGHT THURS.
ELSEWHERE...THE MOISTURE QUICKLY DRIES UP...BUT THE AIRMASS IS
COLD ENOUGH THAT LIGHT SNOW SHOWERS OR FLURRIES COULD PERSIST
THROUGH LATE THURS EVENING.
EXPECT MOUNTAINOUS LOCATIONS TO BE IN THE SINGLE DIGITS TO BELOW
ZERO...AS WELL AS SINGLE DIGITS IN SOUTHEAST OHIO FRIDAY MORNING.
ADDING TO THIS IS THE STRONG...GUSTY WINDS THAT WILL DRIVE WIND
CHILLS TO NEAR 0 ACROSS THE LOWLANDS AND WELL BELOW 0 IN THE
MOUNTAINS. STILL EXPECTING WIND CHILL ADVISORY CRITERIA TO BE MET
ACROSS MUCH OF THE MOUNTAINOUS COUNTIES AND PARTS OF NORTHERN WV.
WILL CONTINUE TO HIGHLIGHT IN THE HWO.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
MODELS SHOW STRONG UPPER TROUGH MOVING EAST OF THE APPALACHIANS BY
00Z FRIDAY. MUCH FRIGID AIR RUSHES IN UNDER NORTHWEST FLOW
BRINGING H850 TEMPERATURES INTO THE MINUS 20C. LINGERING MOISTURE
MAY STILL PRODUCE LIGHT FLUFFY SNOW OR FLURRIES ALONG THE EASTERN
MOUNTAINS ENDING TOWARDS FRIDAY MORNING. STRONG GUSTY WINDS AND
SFC TEMPERATURES FROM THE TEENS TO THE SINGLE DIGITS LOWLANDS AND
EVEN SINGLE DIGITS BELOW WILL PRODUCE DANGEROUS WIND CHILL VALUES
THURSDAY NIGHT INTO FRIDAY MORNING OVER THE NORTHEAST MOUNTAINS.
THERE COULD BE A SLIGHT WARM UP POSSIBLE MAINLY ACROSS THE
LOWLANDS SATURDAY NIGHT. ANOTHER BUT EVEN COLDER ARCTIC BLAST
EXPECTED AS AN UPPER LEVEL LOW PRESSURE CROSSES JUST NORTH OF THE
AREA SATURDAY NIGHT INTO SUNDAY...WITH EVEN COLDER AIR AT H850
REACHING THE MINUS 28C MARK. WIND CHILL ADVISORIES MAY BE NEEDED
FOR THESE TWO EVENTS ACROSS THE NORTHEAST MOUNTAINS AND HAVE BEEN
MENTIONED IN THE HWO.
A WEAK CLIPPER CROSSES THROUGH THE WEEKEND WITH LOW CHANCES OF
PCPN.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
IFR CEILINGS CONTINUE AT MOUNTAIN SITES WITH LITTLE OR NO
IMPROVEMENT EXPECTED THIS AFTERNOON. CONDITIONS WILL DETERIORATE
AGAIN AT BOTH SITES OVERNIGHT. REMAINING TERMINALS HAVE IMPROVED TO
MVFR/MOSTLY VFR CEILINGS AS DRY AIR INTRUDES LOW LEVELS. LOW LAND
SITES ARE EXPECTED TO DROP BACK TO MOSTLY MVFR CONDITIONS AT TIMES
AS TEMPERATURES DECREASE OVERNIGHT. ALL TERMINAL SITES WILL SEE
GRADUAL IMPROVEMENT AS FLOW BECOMES SW WITH SURFACE HIGH PRESSURE IN
PLACE.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIO: TIMING OF IMPROVEMENT MAY VARY. MVFR CIGS MAY
NOT MATERIALIZE TONIGHT. IFR FOG IN THE MOUNTAINS OVERNIGHT
TONIGHT MAY NOT HAPPEN EITHER.
AFTER 18Z WEDNESDAY...
IFR IN THE MOUNTAINOUS COUNTIES IN SNOW SHOWERS ON THURSDAY AND
AGAIN SATURDAY AFTERNOON...EACH IN THE WAKE OF ARCTIC FRONTS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/SL/TAX
NEAR TERM...TAX
SHORT TERM...TAX
LONG TERM...ARJ
AVIATION...RG
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1124 AM EST TUE FEB 10 2015
.SYNOPSIS...
DRIER AIR GRADUALLY PUSHES SOUTH TODAY...AHEAD OF HIGH PRESSURE
BUILDING IN TONIGHT. ARCTIC FRONTS CROSS WEDNESDAY NIGHT AND AGAIN
ON SATURDAY....AND MAYBE EVEN AGAIN NEXT WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
CURRENT SATELLITE IMAGERY SHOWS THE AREA BLANKETED BY LLVL STRATUS
AIDED BY RESIDUAL MOISTURE FROM THE SFC LOW NOW PULLING AWAY FROM THE
MID-ATLANTIC COAST. SOME CLEARING IS BEING OBSERVED IN THE FAR NW
COUNTIES OF OUR CWA AS THE MOISTURE IS SLOWLY ERODED BY DRIER AIR
FROM THE WEST. THE RAP HAS A PRETTY GOOD HANDLE ON THIS AND WILL
BE FOLLOWED FOR THIS TREND THROUGH THE EVENING. MOISTURE WILL HOLD
LONGER IN THE MNTS WHERE EARLIER DRIZZLE AND FOG WERE OBSERVED.
RELATIVELY QUIET NIGHT ON TAP WITH CLOUD COVER CONTINUING TO ERODE
AS THE UPPER RIDGE SETTLES IN. TEMPERATURES WILL REMAIN ON THE
COOL SIDE TONIGHT AS WE DECOUPLE...BUT WAA BEGINS TO KICK FOR
DAYBREAK AND MIXING WILL BRING WEDS TEMPS BACK UP INTO THE 40S FOR
MOST LOCATIONS.
FOR AS LONG AS IT TOOK THE SW RIDGE TO BUILD IN AND DRY THINGS
OUT...IT UNFORTUNATELY WONT STAY LONG. THE FIRST IN A SERIES OF
UPPER LEVEL WAVES WILL ARRIVE EARLY WEDS AFTERNOON...BRINGING
MAINLY CLOUDS BACK TO THE AREA. AS THE UPPER LEVEL WAVE
ARRIVES...IT DEAMPLIFIES AND THE FLOW ALOFT BECOMES MORE ZONAL.
STILL...SOME WEAK MID-LEVEL CONVERGENCE EXISTS AHEAD OF THE FIRST
WAVE AND MODELS HAVE CONSISTENTLY INCLUDED QPF WITH LIGHT SHOWERS
WEDS EVENING. NOT SOLD ON THE IDEA...BUT WITH THIS FEATURE EVEN
RESOLVED IN THE COARSER SUITE OF MODELS...THOUGHT IS WAS PRUDENT
TO INTRODUCE SLGHT CHC POPS.
&&
.SHORT TERM /WEDNESDAY NIGHT/...
ACTIVE AND COLD WEATHER PATTERN IN THE SHORT TERM PERIOD AS A COLD
FRONT AND UPPER TROUGH DIG SOUTH ACROSS THE REGION THURSDAY INTO
FRIDAY. EXPECT A SHARP DROP IN TEMPERATURES THROUGHOUT THE DAY ON
THURSDAY...AND A GRADUAL CHANGE OVER TO SNOW...WITH LIGHT
ACCUMULATIONS POSSIBLE. IN ADDITION...GUSTY WINDS WILL MAKE FOR A
RATHER BLUSTERY DAY AND NIGHT...WITH -21C AIR AT 850MB PROGGED TO
MOVE INTO THE AREA THURSDAY NIGHT...EXPECT MOUNTAINOUS LOCATIONS TO
BE IN THE SINGLE DIGITS TO BELOW ZERO...AS WELL AS SINGLE DIGITS IN
SOUTHEAST OHIO FRIDAY MORNING. THIS...COMBINED WITH THE CONTINUED
GUSTY WINDS...AM STILL EXPECTING WIND CHILL ADVISORY CRITERIA TO BE
MET ACROSS MUCH OF THE MOUNTAINOUS COUNTIES AND PARTS OF NORTHERN
WV. WILL CONTINUE TO HIGHLIGHT IN THE HWO.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
MODELS SHOW STRONG UPPER TROUGH MOVING EAST OF THE APPALACHIANS BY
00Z FRIDAY. MUCH FRIGID AIR RUSHES IN UNDER NORTHWEST FLOW
BRINGING H850 TEMPERATURES INTO THE MINUS 20C. LINGERING MOISTURE
MAY STILL PRODUCE LIGHT FLUFFY SNOW OR FLURRIES ALONG THE EASTERN
MOUNTAINS ENDING TOWARDS FRIDAY MORNING. STRONG GUSTY WINDS AND
SFC TEMPERATURES FROM THE TEENS TO THE SINGLE DIGITS LOWLANDS AND
EVEN SINGLE DIGITS BELOW WILL PRODUCE DANGEROUS WIND CHILL VALUES
THURSDAY NIGHT INTO FRIDAY MORNING OVER THE NORTHEAST MOUNTAINS.
THERE COULD BE A SLIGHT WARM UP POSSIBLE MAINLY ACROSS THE
LOWLANDS SATURDAY NIGHT. ANOTHER BUT EVEN COLDER ARCTIC BLAST
EXPECTED AS AN UPPER LEVEL LOW PRESSURE CROSSES JUST NORTH OF THE
AREA SATURDAY NIGHT INTO SUNDAY...WITH EVEN COLDER AIR AT H850
REACHING THE MINUS 28C MARK. WIND CHILL ADVISORIES MAY BE NEEDED
FOR THESE TWO EVENTS ACROSS THE NORTHEAST MOUNTAINS AND HAVE BEEN
MENTIONED IN THE HWO.
A WEAK CLIPPER CROSSES THROUGH THE WEEKEND WITH LOW CHANCES OF
PCPN.
&&
.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
DENSE FOG IN NRLY FLOW AND SATURATED LOW LEVELS AT BKW WILL LIFT
DURING THE MORNING HOURS AND CIGS WILL IMPROVE TO MVFR. FARTHER N
UP THE MOUNTAINS...IFR CIGS AND MVFR VSBY AT EKN WILL IMPROVE THIS
MORNING...WITH MVFR CIGS AND VFR VSBY THIS AFTERNOON. CONDITIONS
WILL DETERIORATE IN THE MOUNTAINS /BOTH OF THESE SITES/ LATE
TONIGHT WITH IFR FOG BRIEFLY POSSIBLE BEFORE DAWN. THE CLOUDS MAY
START TO BREAK RIGHT AT THE END OF THE PERIOD AT BKW.
OUT ACROSS THE LOWLANDS...MVFR CIGS THIS MORNING WILL IMPROVE TO VFR
FOR THIS AFTERNOON. THEY WILL DROP BACK TO MVFR TONIGHT BUT THEN
CLEARING WILL BE TAKING PLACE W TO E LATE TODAY AND TONIGHT.
N SFC FLOW THROUGH TODAY WILL BECOME LIGHT AND VARIABLE TONIGHT.
LIGHT N FLOW ALOFT WILL VEER TO LIGHT NE THIS AFTERNOON AND THEN TO
LIGHT E TONIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIO: TIMING OF IMPROVEMENT THIS MORNING MAY VARY.
MVFR CIGS MAY NOT MATERIALIZE TONIGHT. IFR FOG IN THE MOUNTAINS
OVERNIGHT TONIGHT MAY NOT HAPPEN EITHER.
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.
AFTER 18Z WEDNESDAY...
IFR IN THE MOUNTAINOUS COUNTIES IN SNOW SHOWERS ON THURSDAY AND
AGAIN SATURDAY AFTERNOON...EACH IN THE WAKE OF ARCTIC FRONTS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TAX/TRM/SL
NEAR TERM...TAX
SHORT TERM... SL
LONG TERM... ARJ
AVIATION...TRM
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
442 PM EST TUE FEB 10 2015
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL BUILD INTO PENNSYLVANIA TODAY AND
WEDNESDAY. A PAIR OF POTENT SHORTWAVES AND ASSOC CLIPPERS WILL
CARVE OUT A DEEP UPPER LVL TROUGH OVER THE NORTHEAST CONUS LATE
THIS WEEK THROUGH EARLY NEXT WEEK. THESE SYSTEMS WILL BRING COLD
BITTER AIR BACK INTO CENTRAL PENNSYLVANIA THROUGH THE SECOND HALF
OF THE WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS A RIDGE OF HIGH PRESSURE REMAINS OVER THE REGION...LARGE SCALE
SUBSIDENCE DOMINATES THE FORECAST THROUGH TOMORROW. THE MAIN
CONCERN WILL BE HOW MUCH CLEARING IS OBSERVED. CURRENT HRRR AND
MODEL SOUNDINGS SUGGEST STRATOCU WILL CONTINUE THROUGH THE REST OF
THE AFTERNOON AND INTO THE EVENING. THE WINDS ARE COMING FROM THE
NORTH TO NORTHEAST...AND AS THEY SHIFT TO THE EAST...THERE WILL BE
SOME DRY AIR ADVECTION. THE THICKEST CLOUDS CONTINUE TO BE OVER
THE CENTRAL AND NW MTNS...ESPECIALLY THE LAURELS...WHERE LOW
STRATOCU...UPSLOPE FLOW...AND LOW LEVEL MOISTURE FROM YESTERDAYS
PRECIPITATION AND CORRESPONDING MELTED SNOWPACK HAVE ALLOWED FOR
REDUCED VISIBILITIES AS WELL. THESE CONDITIONS WILL SLOWLY WEAKEN
AS THE NIGHT CONTINUES AS THE RIDGE FLATTENS...AND MORE ZONAL
UPPER LEVEL FLOW MOVES OVER THE REGION FOR TOMORROW.
FAIR WX EXPECTED TONIGHT AS THE DRY AIR MOVES INTO THE
REGION...CLOUDS WILL SLOWLY BREAK UP AND DISSIPATE. IF THE SFC
DECOUPLES OVERNIGHT...THERE IS A CHANCE FOR SOME LOW CLOUDS TO
REDEVELOP...MAINLY OVER THE CENTRAL AND NORTHWEST MOUNTAINS.
LIGHT WINDS...CLEARING SKIES AND SNOW COVER SHOULD ALLOW TEMPS TO
FALL SEVERAL DEG BLW SEASONAL NORMS WITH TEMPERATURES RANGING FROM
THE LOW SINGLE DIGITS IN THE NORTHEAST...TO THE MID TO UPPER TEENS
ELSEWHERE.
OVERALL FAIR WEATHER WILL CONTINUE THROUGH TOMORROW AS A POTENT
SHORTWAVE WILL BE DIVING SOUTHEASTWARD INTO THE GREAT LAKES REGION
LATE WEDNESDAY. THE WINDS SHIFT TO THE NORTHWEST OUT AHEAD OF THIS
TROUGH. THIS SYSTEM WILL BRING AN INCREASE CHANCE FOR
PRECIPITATION THROUGH THE NW MTNS LATE WEDNESDAY.
PARTIAL SUNSHINE AND A BRIEF SHOT OF WAA IN ADVANCE OF CLIPPER
SHOULD HELP TEMPS RECOVER TO NEAR NORMAL WED AFTN WITH MAXES
MOSTLY IN THE LOW TO MID 30S.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
THE WAVE TRAIN OF ALBERTA CLIPPERS BEGINS WEDNESDAY NIGHT AND
THURSDAY. NOT MANY SIGNIFICANT CHANGES HAVE OCCURRED IN THE MODEL
CONSENSUS TRACK AND INTENSITY OF THESE FEATURES OVER THE PAST 24
HOURS...SO MINOR MODIFICATIONS TO POPS...TEMPS..AND WIND/WIND
CHILLS HAVE BEEN MADE WITH THIS ROUND OF GRIDDED DATA.
AFTER A BRIEF...SEVERAL-HOUR PERIOD OF WARM ADVECTION CLOUDS AND
A FEW AREAS OF LIGHT SNOW/SNOW SHOWERS ACROSS NRN AND WRN PENN
LATE WED/WED NIGHT...THE FIRST CLIPPER IS STILL TIMED TO PUSH THE
LEADING EDGE OF AN ARCTIC AIRMASS INTO THE COMMONWEALTH LATE WED
NIGHT AND THURSDAY MORNING.
TEMPS STARTING OUT IN THE 20S THURSDAY MORNING WILL BE FOLLOWED
BY GRADUALLY FALLING TEMPS ALL DAY /AT LEAST ACROSS CENTRAL AND
NWRN PENN/ WITH NUMEROUS SNOW SHOWERS FLYING ACROSS THE
ALLEGHENIES...AND FLURRIES/SCATTERED SNOW SHOWERS OCCURRING
THROUGHOUT THE CENTRAL RIDGE AND VALLEY REGION.
AN ACCUMULATION OF 1-3 INCHES APPEARS POSSIBLE ACROSS THE LAURELS
AND NW MTNS...WHILE JUST A COATING TO ONE HALF OF AN INCH IS
EXPECTED ELSEWHERE.
AS THE LEADING EDGE OF THE VERY COLD MID LEVEL AIR PUSHES SE
ACROSS THE STATE DURING PRIME HEATING OF THE LATE MORNING AND
AFTERNOON HOURS...850-500 MB LAPSE RATES WILL STEEPEN TO AROUND
6.5C/KM WHICH WILL SUPPORT SOME BRIEF...HEAVY SNOW SHOWERS/SQUALLS.
SHOULD THIS SCENARIO BECOME MORE EVIDENT...POPS ACROSS THE SE HALF
OF THE CWA WILL NEED TO BE INCREASED FOR ANTICIPATED LIGHT ACCUMS
OF SNOW.
NW WINDS INCREASING TO 10-18 KTS WITH GUSTS OCNLY TO 25-30 KTS IN
THE AFTERNOON WILL USHER IN BITTERLY COLD TEMPS AND WIND CHILLS.
WIDESPREAD WIND CHILL ADVISORY VALUES LOOK PROBABLY THROUGHOUT THE
RIDGE AND VALLEY REGION LATE THURSDAY NIGHT/EARLY FRIDAY...WITH
WARNING CRITERIA /LESS THAN -25C/ POSSIBLE ACROSS PORTIONS OF THE
NORTH AND WEST. THE SUSQ VALLEY MAY ESCAPE THE BRUTALLY COLD WIND
CHILLS WITH APPARENT TEMPS OF -10 TO -14F.
LATER SHIFTS - OVERNIGHT TONIGHT OR WEDNESDAY WILL LIKELY BE
POSTING WIND CHILL WATCH/OR ADVISORY FOR THE AFOREMENTIONED
LOCATIONS.
THE ALLEGHENY PLATEAU. A BITING WIND WILL LIKELY ACCOMPANY THE
SUB- ZERO TEMPS...DUE TO TIGHT PRES GRADIENT WEST OF RAPIDLY
DEVELOPING COASTAL STORM EAST OF NEW ENG.
FRIDAY WILL LIKELY BE ONE OF THE COLDEST DAYS OF THE WINTER SEASON
SO FAR WITH ANOMALOUSLY GEFS MEAN 850 MB TEMPS STILL FCST TO
PLUMMET TO ARND -20C OVER THE AREA. HIGH TEMPS FRIDAY PROJECTED
TO VARY VARY FROM JUST THE SINGLE DIGITS ACROSS THE NORTHERN
MTNS...TO THE MID AND UPPER TEENS ACROSS THE SOUTHERN VALLEYS.
AN EXTENSIVE RIDGE OF HIGH PRESSURE BUILDS EAST ACROSS THE FRIDAY
INTO EARLY FRIDAY NIGHT WITH SLOWLY DECREASING NW WINDS AND
PARTLY TO MOSTLY SUNNY SKIES ACROSS THE CENTRAL AND SE ZONES. THE
NW MTNS MAY HAVE A TOUGH TIME BREAKING UP THE SHALLOW STRATO CU
THOUGH...SO HEDGED TOWARD MSTLY CLOUDY ACROSS THE NRN AND WRN MTNS
/BUT WITH LITTLE MORE THAN SOME FLURRIES/.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE NEXT CAR IN THE CLIPPER TRAIN RIDES ACROSS THE CWA LATE
FRIDAY NIGHT AND SATURDAY...ACCOMPANIED BY NUMEROUS SNOW
SHOWERS...OR EVEN A FEW PERIODS OF STEADY SNOW INTO SATURDAY
EVENING AS SOME MODEL GUIDANCE INDICATES A CLOSED MID/UPPER LOW
CENTER FORMING OVER CENTRAL/ERN PENN BEFORE SCOOTING QUICKLY EAST
OFF THE MID ATLANTIC COAST. AIR BEHIND THIS SYSTEM WILL BE EVEN A
FEW-SVRL DEG F COLDER THAN THE INITIAL LATE WEEK CLIPPER. TEMPS
SHOULD STEADILY FALL /FROM THEIR ALREADY BELOW NORMAL VALUES/
SATURDAY AFTERNOON/EVENING...WITH A FEW SQUALLS EMBEDDED IN THE
LARGER SCALE AREAS OF LIGHTER SNOW.
AS THE SFC LOW RAPIDLY DEEPENS JUST OFF THE MID ATLANTIC/SRN NEW
ENGLAND COAST SAT NIGHT/SUNDAY...NW WINDS WILL INCREASE TO
SUSTAINED SPEEDS IN THE TEENS-LOW 20 KT RANGE WITH GUSTS UP TO 30
KTS...SIMILAR OR COLDER WIND CHILLS /THAN THURSDAY NIGHT`S ARE
EXPECTED BY VERY EARLY SUNDAY/.
A TRUE TASTE OF THE ARCTIC WILL BE PLATED UP FOR RESIDENTS OF
PENN SUNDAY...WITH MEAN GEFS 850 MB TEMPS BOTTOMING OUT IN THE
LOW-MID -20C RANGE - RESULTING IN SFC MAX TEMPS POSSIBLY STAYING
JUST BELOW ZERO ACROSS THE NRN MTNS...AND ONLY REACHING THE UPPER
SINGLE DIGITS TO MID TEENS AT BEST ACROSS THE CENTRAL AND SRN
PORTIONS OF THE STATE.
GRADUAL CLEARING FOR SUNDAY NIGHT/MONDAY AS A LARGE AREA OF HIGH
PRESSURE SETTLES SE ACROSS THE STATE. SHOULD THE WIND DIMINISH AND
SKIES CLEAR OUT QUICK ENOUGH...WIDESPREAD SUB-ZERO TEMPS ARE WOULD
BECOME LIKELY...WITH EVEN SOME RECORD MINS FOR THE DATE POSSIBLE.
FOR A QUICK EXAMPLE...WILLIAMSPORT`S LOW FOR FEB 16TH IS -5F SET
OVER A CENTURY AGO IN 1905...AND OUR FCST LOW THERE NEXT TUESDAY
MORNING IS IS -3F. GEFS MIN TEMP RANGE FOR KITP ON FEB 16TH IS
BETWEEN -3F AND -14F...SO I/M BEING OPTIMISTICALLY WARM- HEARTED
WITH THAT FCST LOW RIGHT AFTER V-DAY.
THE THIRD DIGGING SHORTWAVE /POSSIBLE CABOOSE/ TUESDAY...MAY HELP
TO BRIEFLY CARVE OUT THE MEAN ERN U.S. A LITTLE FURTHER TO THE
WEST /WHILE TEAMING UP WITH SOME SRN STREAM ENERGY/ ALLOWING FOR
SOME GOMEX MOISTURE TO BE PICKED UP BY THE SYSTEM BEFORE IT HEADS
EAST- NORTHEAST TWD THE VA/MID ATLANTIC COAST. FOR NOW...AND AT
THIS TIME RANGE WILL GO WITH ABOVE CLIMO POPS ACROSS THE CENTRAL
AND EAST FOR CHC OF LIGHT SNOW OR SNOW SHOWERS /DEPENDING ON
WHETHER WE SEE A DOMINANT NRN STREAM CLIPPER...OR PHASING NRN AND
SRN STREAM FEATURES/. TEMPS MONDAY AND TUESDAY WILL SLOWLY REBOUND
BUT LIKELY STAY SEVERAL DEG F BELOW NORMAL.
&&
.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
SOME CLEARING TO THE EAST AND SE. NOT IN A BIG RUSH TO BRING
MUCH CLEARING TO THE WEST...GIVEN WEATHER PATTERN AND TIME OF
DAY.
MINOR ADJUSTMENTS MADE TO 21Z TAFS.
EARLIER DISCUSSION BELOW.
SUB VFR CONDS WILL CONTINUE AS LOW LEVEL MOISTURE REMAINS
ENTRENCHED BEHIND MONDAYS STORM SYSTEM. NO ACTIVE PCPN IS
AFFECTING THE AIRSPACE...AND NONE IS EXPECTED THROUGH TOMORROW
AFTERNOON. LOWEST CONDS...IFR OR LOWER CIGS...ARE AT BFD AND JST.
JST IS DUE TO FOG/MIST/HAZE DUE TO RESIDUAL MOISTURE FROM MELTING
SNOW...AND THICK LOW CLOUDS. EXPECT SLOW IMPROVING TREND FROM
NORTH TO SOUTH THIS AFTERNOON INTO TONIGHT WITH VFR RETURNING TO
MOST AREAS BY TUESDAY OVERNIGHT...AS HIGH PRESSURE BUILDS INTO THE
REGION.
JST AND BFD SHOULD IMPROVE 00Z TO 06Z...BUT CONDS MAY VERY WELL
GO LOW AGAIN TONIGHT ESPECIALLY AT KBFD AND KJST AS WINDS GO CALM
AND POSSIBLE MVFR TO A BRIEF PERIOD OF IFR REDEVELOPS TOWARDS
WEDNESDAY MORNING.
AROUND 12 TO 15Z CONDITIONS SHOULD IMPROVE WITH VFR DOMINATING
THE PATTERN TOMORROW. CONDITIONS WILL DETERIORATE AS ANOTHER
TROUGH DROPS THROUGH THE GREAT LAKES AND THROUGH PENNSYLVANIA
WEDNESDAY NIGHT INTO THURSDAY.
OUTLOOK...
WED NGT-THU...MVFR/IFR IN -SN. GUSTY NW WINDS THU NIGHT INTO
EARLY FRI BEHIND FROPA.
FRI...MVFR/IFR WITH -SHSN WEST.
SAT...MVFR/IFR WITH -SN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD/CERU
NEAR TERM...FITZGERALD/CERU/MARTIN
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/LAMBERT
AVIATION...CERU/GARTNER/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
403 PM EST TUE FEB 10 2015
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL BUILD INTO PENNSYLVANIA TODAY AND
WEDNESDAY. A PAIR OF POTENT SHORTWAVES AND ASSOC CLIPPERS WILL
CARVE OUT A DEEP UPPER LVL TROUGH OVER THE NORTHEAST CONUS LATE
THIS WEEK THROUGH EARLY NEXT WEEK. THESE SYSTEMS WILL BRING COLD
BITTER AIR BACK INTO CENTRAL PENNSYLVANIA THROUGH THE SECOND HALF
OF THE WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS A RIDGE OF HIGH PRESSURE REMAINS OVER THE REGION...LARGE SCALE
SUBSIDENCE DOMINATES THE FORECAST THROUGH TOMORROW. THE MAIN
CONCERN WILL BE HOW MUCH CLEARING IS OBSERVED. CURRENT HRRR AND
MODEL SOUNDINGS SUGGEST STRATOCU WILL CONTINUE THROUGH THE REST OF
THE AFTERNOON AND INTO THE EVENING. THE WINDS ARE COMING FROM THE
NORTH TO NORTHEAST...AND AS THEY SHIFT TO THE EAST...THERE WILL BE
SOME DRY AIR ADVECTION. THE THICKEST CLOUDS CONTINUE TO BE OVER
THE CENTRAL AND NW MTNS...ESPECIALLY THE LAURELS...WHERE LOW
STRATOCU...UPSLOPE FLOW...AND LOW LEVEL MOISTURE FROM YESTERDAYS
PRECIPITATION AND CORRESPONDING MELTED SNOWPACK HAVE ALLOWED FOR
REDUCED VISIBILITIES AS WELL. THESE CONDITIONS WILL SLOWLY WEAKEN
AS THE NIGHT CONTINUES AS THE RIDGE FLATTENS...AND MORE ZONAL
UPPER LEVEL FLOW MOVES OVER THE REGION FOR TOMORROW.
FAIR WX EXPECTED TONIGHT AS THE DRY AIR MOVES INTO THE
REGION...CLOUDS WILL SLOWLY BREAK UP AND DISSIPATE. IF THE SFC
DECOUPLES OVERNIGHT...THERE IS A CHANCE FOR SOME LOW CLOUDS TO
REDEVELOP...MAINLY OVER THE CENTRAL AND NORTHWEST MOUNTAINS.
LIGHT WINDS...CLEARING SKIES AND SNOW COVER SHOULD ALLOW TEMPS TO
FALL SEVERAL DEG BLW SEASONAL NORMS WITH TEMPERATURES RANGING FROM
THE LOW SINGLE DIGITS IN THE NORTHEAST...TO THE MID TO UPPER TEENS
ELSEWHERE.
OVERALL FAIR WEATHER WILL CONTINUE THROUGH TOMORROW AS A POTENT
SHORTWAVE WILL BE DIVING SOUTHEASTWARD INTO THE GREAT LAKES REGION
LATE WEDNESDAY. THE WINDS SHIFT TO THE NORTHWEST OUT AHEAD OF
THIS TROUGH. THIS SYSTEM WILL BRING AN INCREASE CHANCE FOR
PRECIPITATION THROUGH THE NW MTNS LATE WEDNESDAY.
PARTIAL SUNSHINE AND A BRIEF SHOT OF WAA IN ADVANCE OF CLIPPER
SHOULD HELP TEMPS RECOVER TO NEAR NORMAL WED AFTN WITH MAXES
MOSTLY IN THE LOW TO MID 30S.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
THE WAVE TRAIN OF ALBERTA CLIPPERS BEGINS WEDNESDAY NIGHT AND
THURSDAY. NOT MANY SIGNIFICANT CHANGES HAVE OCCURRED IN THE MODEL
CONSENSUS TRACK AND INTENSITY OF THESE FEATURES OVER THE PAST 24
HOURS...SO MINOR MODIFICATIONS TO POPS...TEMPS..AND WIND/WIND
CHILLS HAVE BEEN MADE WITH THIS ROUND OF GRIDDED DATA.
AFTER A BRIEF...SEVERAL-HOUR PERIOD OF WARM ADVECTION CLOUDS AND
A FEW AREAS OF LIGHT SNOW/SNOW SHOWERS ACROSS NRN AND WRN PENN
LATE WED/WED NIGHT...THE FIRST CLIPPER IS STILL TIMED TO PUSH THE
LEADING EDGE OF AN ARCTIC AIRMASS INTO THE COMMONWEALTH LATE WED
NIGHT AND THURSDAY MORNING.
TEMPS STARTING OUT IN THE 20S THURSDAY MORNING WILL BE FOLLOWED
BY GRADUALLY FALLING TEMPS ALL DAY /AT LEAST ACROSS CENTRAL AND
NWRN PENN/ WITH NUMEROUS SNOW SHOWERS FLYING ACROSS THE
ALLEGHENIES...AND FLURRIES/SCATTERED SNOW SHOWERS OCCURRING
THROUGHOUT THE CENTRAL RIDGE AND VALLEY REGION.
AN ACCUMULATION OF 1-3 INCHES APPEARS POSSIBLE ACROSS THE LAURELS
AND NW MTNS...WHILE JUST A COATING TO ONE HALF OF AN INCH IS
EXPECTED ELSEWHERE.
AS THE LEADING EDGE OF THE VERY COLD MID LEVEL AIR PUSHES SE
ACROSS THE STATE DURING PRIME HEATING OF THE LATE MORNING AND
AFTERNOON HOURS...850-500 MB LAPSE RATES WILL STEEPEN TO AROUND
6.5C/KM WHICH WILL SUPPORT SOME BRIEF...HEAVY SNOW SHOWERS/SQUALLS.
SHOULD THIS SCENARIO BECOME MORE EVIDENT...POPS ACROSS THE SE HALF
OF THE CWA WILL NEED TO BE INCREASED FOR ANTICIPATED LIGHT ACCUMS
OF SNOW.
NW WINDS INCREASING TO 10-18 KTS WITH GUSTS OCNLY TO 25-30 KTS IN
THE AFTERNOON WILL USHER IN BITTERLY COLD TEMPS AND WIND CHILLS.
WIDESPREAD WIND CHILL ADVISORY VALUES LOOK PROBABLY THROUGHOUT THE
RIDGE AND VALLEY REGION LATE THURSDAY NIGHT/EARLY FRIDAY...WITH
WARNING CRITERIA /LESS THAN -25C/ POSSIBLE ACROSS PORTIONS OF THE
NORTH AND WEST. THE SUSQ VALLEY MAY ESCAPE THE BRUTALLY COLD WIND
CHILLS WITH APPARENT TEMPS OF -10 TO -14F.
LATER SHIFTS - OVERNIGHT TONIGHT OR WEDNESDAY WILL LIKELY BE
POSTING WIND CHILL WATCH/OR ADVISORY FOR THE AFOREMENTIONED
LOCATIONS.
THE ALLEGHENY PLATEAU. A BITING WIND WILL LIKELY ACCOMPANY THE
SUB- ZERO TEMPS...DUE TO TIGHT PRES GRADIENT WEST OF RAPIDLY
DEVELOPING COASTAL STORM EAST OF NEW ENG.
FRIDAY WILL LIKELY BE ONE OF THE COLDEST DAYS OF THE WINTER SEASON
SO FAR WITH ANOMALOUSLY GEFS MEAN 850 MB TEMPS STILL FCST TO
PLUMMET TO ARND -20C OVER THE AREA. HIGH TEMPS FRIDAY PROJECTED
TO VARY VARY FROM JUST THE SINGLE DIGITS ACROSS THE NORTHERN
MTNS...TO THE MID AND UPPER TEENS ACROSS THE SOUTHERN VALLEYS.
AN EXTENSIVE RIDGE OF HIGH PRESSURE BUILDS EAST ACROSS THE FRIDAY
INTO EARLY FRIDAY NIGHT WITH SLOWLY DECREASING NW WINDS AND
PARTLY TO MOSTLY SUNNY SKIES ACROSS THE CENTRAL AND SE ZONES. THE
NW MTNS MAY HAVE A TOUGH TIME BREAKING UP THE SHALLOW STRATO CU
THOUGH...SO HEDGED TOWARD MSTLY CLOUDY ACROSS THE NRN AND WRN MTNS
/BUT WITH LITTLE MORE THAN SOME FLURRIES/.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE NEXT CAR IN THE CLIPPER TRAIN RIDES ACROSS THE CWA LATE
FRIDAY NIGHT AND SATURDAY...ACCOMPANIED BY NUMEROUS SNOW
SHOWERS...OR EVEN A FEW PERIODS OF STEADY SNOW INTO SATURDAY
EVENING AS SOME MODEL GUIDANCE INDICATES A CLOSED MID/UPPER LOW
CENTER FORMING OVER CENTRAL/ERN PENN BEFORE SCOOTING QUICKLY EAST
OFF THE MID ATLANTIC COAST. AIR BEHIND THIS SYSTEM WILL BE EVEN A
FEW-SVRL DEG F COLDER THAN THE INITIAL LATE WEEK CLIPPER. TEMPS
SHOULD STEADILY FALL /FROM THEIR ALREADY BELOW NORMAL VALUES/
SATURDAY AFTERNOON/EVENING...WITH A FEW SQUALLS EMBEDDED IN THE
LARGER SCALE AREAS OF LIGHTER SNOW.
AS THE SFC LOW RAPIDLY DEEPENS JUST OFF THE MID ATLANTIC/SRN NEW
ENGLAND COAST SAT NIGHT/SUNDAY...NW WINDS WILL INCREASE TO
SUSTAINED SPEEDS IN THE TEENS-LOW 20 KT RANGE WITH GUSTS UP TO 30
KTS...SIMILAR OR COLDER WIND CHILLS /THAN THURSDAY NIGHT`S ARE
EXPECTED BY VERY EARLY SUNDAY/.
A TRUE TASTE OF THE ARCTIC WILL BE PLATED UP FOR RESIDENTS OF
PENN SUNDAY...WITH MEAN GEFS 850 MB TEMPS BOTTOMING OUT IN THE
LOW-MID -20C RANGE - RESULTING IN SFC MAX TEMPS POSSIBLY STAYING
JUST BELOW ZERO ACROSS THE NRN MTNS...AND ONLY REACHING THE UPPER
SINGLE DIGITS TO MID TEENS AT BEST ACROSS THE CENTRAL AND SRN
PORTIONS OF THE STATE.
GRADUAL CLEARING FOR SUNDAY NIGHT/MONDAY AS A LARGE AREA OF HIGH
PRESSURE SETTLES SE ACROSS THE STATE. SHOULD THE WIND DIMINISH AND
SKIES CLEAR OUT QUICK ENOUGH...WIDESPREAD SUB-ZERO TEMPS ARE WOULD
BECOME LIKELY...WITH EVEN SOME RECORD MINS FOR THE DATE POSSIBLE.
FOR A QUICK EXAMPLE...WILLIAMSPORT`S LOW FOR FEB 16TH IS -5F SET
OVER A CENTURY AGO IN 1905...AND OUR FCST LOW THERE NEXT TUESDAY
MORNING IS IS -3F. GEFS MIN TEMP RANGE FOR KITP ON FEB 16TH IS
BETWEEN -3F AND -14F...SO I/M BEING OPTIMISTICALLY WARM- HEARTED
WITH THAT FCST LOW RIGHT AFTER V-DAY.
THE THIRD DIGGING SHORTWAVE /POSSIBLE CABOOSE/ TUESDAY...MAY HELP
TO BRIEFLY CARVE OUT THE MEAN ERN U.S. A LITTLE FURTHER TO THE
WEST /WHILE TEAMING UP WITH SOME SRN STREAM ENERGY/ ALLOWING FOR
SOME GOMEX MOISTURE TO BE PICKED UP BY THE SYSTEM BEFORE IT HEADS
EAST- NORTHEAST TWD THE VA/MID ATLANTIC COAST. FOR NOW...AND AT
THIS TIME RANGE WILL GO WITH ABOVE CLIMO POPS ACROSS THE CENTRAL
AND EAST FOR CHC OF LIGHT SNOW OR SNOW SHOWERS /DEPENDING ON
WHETHER WE SEE A DOMINANT NRN STREAM CLIPPER...OR PHASING NRN AND
SRN STREAM FEATURES/. TEMPS MONDAY AND TUESDAY WILL SLOWLY REBOUND
BUT LIKELY STAY SEVERAL DEG F BELOW NORMAL.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
SUB VFR CONDS WILL CONTINUE AS LOW LEVEL MOISTURE REMAINS
ENTRENCHED BEHIND MONDAYS STORM SYSTEM. NO ACTIVE PCPN IS
AFFECTING THE AIRSPACE...AND NONE IS EXPECTED THROUGH TOMORROW
AFTERNOON. LOWEST CONDS...IFR OR LOWER CIGS...ARE AT BFD AND JST.
JST IS DUE TO FOG/MIST/HAZE DUE TO RESIDUAL MOISTURE FROM MELTING
SNOW...AND THICK LOW CLOUDS. EXPECT SLOW IMPROVING TREND FROM
NORTH TO SOUTH THIS AFTERNOON INTO TONIGHT WITH VFR RETURNING TO
MOST AREAS BY TUESDAY OVERNIGHT...AS HIGH PRESSURE BUILDS INTO THE
REGION.
JST AND BFD SHOULD IMPROVE 00Z TO 06Z...BUT CONDS MAY VERY WELL
GO LOW AGAIN TONIGHT ESPECIALLY AT KBFD AND KJST AS WINDS GO CALM
AND POSSIBLE MVFR TO A BRIEF PERIOD OF IFR REDEVELOPS TOWARDS
WEDNESDAY MORNING.
AROUND 12 TO 15Z CONDITIONS SHOULD IMPROVE WITH VFR DOMINATING
THE PATTERN TOMORROW. CONDITIONS WILL DETERIORATE AS ANOTHER
TROUGH DROPS THROUGH THE GREAT LAKES AND THROUGH PENNSYLVANIA
WEDNESDAY NIGHT INTO THURSDAY.
OUTLOOK...
WED NGT-THU...MVFR/IFR IN -SN. GUSTY NW WINDS THU NIGHT INTO
EARLY FRI BEHIND FROPA.
FRI...MVFR/IFR WITH -SHSN WEST.
SAT...MVFR/IFR WITH -SN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD/CERU
NEAR TERM...FITZGERALD/CERU
SHORT TERM...LAMBERT
LONG TERM...LAMBERT
AVIATION...CERU/GARTNER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
245 PM EST TUE FEB 10 2015
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL BUILD INTO PENNSYLVANIA TODAY AND
WEDNESDAY. A PAIR OF POTENT SHORTWAVES AND ASSOC CLIPPERS WILL
CARVE OUT A DEEP UPPER LVL TROUGH OVER THE NORTHEAST CONUS LATE
THIS WEEK THROUGH EARLY NEXT WEEK. THESE SYSTEMS WILL BRING COLD
BITTER AIR BACK INTO CENTRAL PENNSYLVANIA THROUGH THE SECOND HALF
OF THE WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS A RIDGE OF HIGH PRESSURE REMAINS OVER THE REGION...LARGE SCALE
SUBSIDENCE DOMINATES THE FORECAST THROUGH TOMORROW. THE MAIN
CONCERN WILL BE HOW MUCH CLEARING IS OBSERVED. CURRENT HRRR AND
MODEL SOUNDINGS SUGGEST STRATOCU WILL CONTINUE THROUGH THE REST OF
THE AFTERNOON AND INTO THE EVENING. THE WINDS ARE COMING FROM THE
NORTH TO NORTHEAST...AND AS THEY SHIFT TO THE EAST...THERE WILL BE
SOME DRY AIR ADVECTION. THE THICKEST CLOUDS CONTINUE TO BE OVER
THE CENTRAL AND NW MTNS...ESPECIALLY THE LAURELS...WHERE LOW
STRATOCU...UPSLOPE FLOW...AND LOW LEVEL MOISTURE FROM YESTERDAYS
PRECIPITATION AND CORRESPONDING MELTED SNOWPACK HAVE ALLOWED FOR
REDUCED VISIBILITIES AS WELL. THESE CONDITIONS WILL SLOWLY WEAKEN
AS THE NIGHT CONTINUES AS THE RIDGE FLATTENS...AND MORE ZONAL
UPPER LEVEL FLOW MOVES OVER THE REGION FOR TOMORROW.
FAIR WX EXPECTED TONIGHT AS THE DRY AIR MOVES INTO THE
REGION...CLOUDS WILL SLOWLY BREAK UP AND DISSIPATE. IF THE SFC
DECOUPLES OVERNIGHT...THERE IS A CHANCE FOR SOME LOW CLOUDS TO
REDEVELOP...MAINLY OVER THE CENTRAL AND NORTHWEST MOUNTAINS.
LIGHT WINDS...CLEARING SKIES AND SNOW COVER SHOULD ALLOW TEMPS TO
FALL SEVERAL DEG BLW SEASONAL NORMS WITH TEMPERATURES RANGING FROM
THE LOW SINGLE DIGITS IN THE NORTHEAST...TO THE MID TO UPPER TEENS
ELSEWHERE.
OVERALL FAIR WEATHER WILL CONTINUE THROUGH TOMORROW AS A POTENT
SHORTWAVE WILL BE DIVING SOUTHEASTWARD INTO THE GREAT LAKES REGION
LATE WEDNESDAY. THE WINDS SHIFT TO THE NORTHWEST OUT AHEAD OF
THIS TROUGH. THIS SYSTEM WILL BRING AN INCREASE CHANCE FOR
PRECIPITATION THROUGH THE NW MTNS LATE WEDNESDAY.
PARTIAL SUNSHINE AND A BRIEF SHOT OF WAA IN ADVANCE OF CLIPPER
SHOULD HELP TEMPS RECOVER TO NEAR NORMAL WED AFTN WITH MAXES
MOSTLY IN THE LOW TO MID 30S.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
BIG CHANGES OCCUR FOR LATE IN THE WEEK BEHIND AN INITIAL ARCTIC
FRONT THAT WILL PLOW SE ACROSS THE STATE LATER WEDNESDAY NIGHT
/NW/ AND THURSDAY MORNING /SERN ZONES/. PAINTED LIKELY POPS FOR
SNOW SHOWERS ACROSS THE NRN AND WESTERN MTNS AS LIMITED LAKE
MOISTURE IS FED INTO THE VERY COLD AIR AND LIFTED ACROSS THE
ALLEGHENIES. POPS MAY EASILY BE UNDERDONE...BUT ACCUMS SHOULD
REMAIN LIGHT DUE TO MOSTLY FROZEN LKS ERIE/HURON AND ALSO DRYNESS
OF ARCTIC AIR MASS.
EXPECT STEADILY FALLING TEMPS ALL DAY THURSDAY WITH NORTHWEST
WINDS GUSTING UP TO 30 KTS AT TIMES. THIS WILL LEAD TO WIND CHILLS
FALLING WELL INTO THE SINGLE DIGITS BY LATE AFTERNOON...THEN WELL
BELOW ZERO AND LIKELY INTO AT LEAST THE WIND CHILL ADVISORY RANGE
THU NIGHT ACROSS THE NRN AND WRN MTNS. LATER SHIFTS MAY NEED TO
CONSIDER A WIND CHILL WATCH FOR THE ALLEGHENY PLATEAU. A BITING
WIND WILL LIKELY ACCOMPANY THE SUB-ZERO TEMPS...DUE TO TIGHT PRES
GRADIENT WEST OF RAPIDLY DEVELOPING COASTAL STORM EAST OF NEW ENG.
FRIDAY WILL LIKELY BE ONE OF THE COLDEST DAYS OF THE WINTER SEASON
SO FAR WITH ANOMALOUSLY GEFS MEAN 850 MB TEMPS OF ARND -20C OVER
THE AREA. HIGH TEMPS WILL VARY FROM JUST THE SINGLE DIGITS ACROSS
THE NORTHERN MTNS...TO THE MID AND UPPER TEENS ACROSS THE SOUTHERN
VALLEYS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
ANOTHER POTENT SHORTWAVE AND ASSOC CLIPPER IS PROGGED BY ALL MED
RANGE GUIDANCE TO DIVE SE ACROSS PA ON SATURDAY. BASED ON THIS
TRACK AND LACK OF MDL SPREAD...HAVE RAMPED UP THE POPS SATURDAY
FOR THE POSSIBILITY OF A WIDESPREAD LIGHT SNOWFALL. EVEN COLDER
AIR IS POISED TO BLAST INTO CENTRAL PA BEHIND SATURDAY/S CLIPPER.
IT/S A LONG WAY OFF...BUT BASED ON ECENS AND GEFS MEAN 8H TEMPS
ARND -24C...SUNDAY COULD BE THE COLDEST DAY WE/LL SEE UNTIL AT
LEAST NEXT WINTER. OUR CURRENT... GRIDDED FCST MAX TEMPS RANGE
FROM THE LOW SINGLE DIGITS NORTH...TO THE MID TEENS SOUTH. THIS
FRIGID AIRMASS IS LIKELY TO BE ACCOMPANIED BY GUSTY NW WINDS ON
WESTERN PERIPHERY OF YET ANOTHER RAPIDLY DEVELOPING COASTAL LOW
EAST OF NEW ENG. SCT LAKE-ENHANCED SNOW SHOWERS ARE LKLY SUN/MON.
HOWEVER...FROZEN LAKES AND DRY AIR MASS SHOULD RESULT IN ONLY LGT
ACCUMS ACROSS THE W MTNS.
MODERATING...BUT STILL COLD...CONDS APPEAR LIKELY EARLY NEXT
WEEK...AS TEMPS REBOUND IN ADVANCE OF NEXT CLIPPER.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
SUB VFR CONDS WILL CONTINUE AS LOW LEVEL MOISTURE REMAINS
ENTRENCHED BEHIND MONDAYS STORM SYSTEM. NO ACTIVE PCPN IS
AFFECTING THE AIRSPACE...AND NONE IS EXPECTED THROUGH TOMORROW
AFTERNOON. LOWEST CONDS...IFR OR LOWER CIGS...ARE AT BFD AND JST.
JST IS DUE TO FOG/MIST/HAZE DUE TO RESIDUAL MOISTURE FROM MELTING
SNOW...AND THICK LOW CLOUDS. EXPECT SLOW IMPROVING TREND FROM
NORTH TO SOUTH THIS AFTERNOON INTO TONIGHT WITH VFR RETURNING TO
MOST AREAS BY TUESDAY OVERNIGHT...AS HIGH PRESSURE BUILDS INTO THE
REGION.
JST AND BFD SHOULD IMPROVE 00Z TO 06Z...BUT CONDS MAY VERY WELL
GO LOW AGAIN TONIGHT ESPECIALLY AT KBFD AND KJST AS WINDS GO CALM
AND POSSIBLE MVFR TO A BRIEF PERIOD OF IFR REDEVELOPS TOWARDS
WEDNESDAY MORNING.
AROUND 12 TO 15Z CONDITIONS SHOULD IMPROVE WITH VFR DOMINATING
THE PATTERN TOMORROW. CONDITIONS WILL DETERIORATE AS ANOTHER
TROUGH DROPS THROUGH THE GREAT LAKES AND THROUGH PENNSYLVANIA
WEDNESDAY NIGHT INTO THURSDAY.
OUTLOOK...
WED NGT-THU...MVFR/IFR IN -SN. GUSTY NW WINDS THU NIGHT INTO
EARLY FRI BEHIND FROPA.
FRI...MVFR/IFR WITH -SHSN WEST.
SAT...MVFR/IFR WITH -SN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD/CERU
NEAR TERM...FITZGERALD/CERU
SHORT TERM...FITZGERALD/CERU
LONG TERM...FITZGERALD/LAMBERT
AVIATION...CERU/GARTNER
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1130 AM CST TUE FEB 10 2015
.AVIATION...
VFR CONDITIONS WILL LIKELY PERSIST INTO THIS EVENING OVER ALL THE
SITES AS HIGH PRESSURE DRIFTS OVERHEAD AND EAST OF THE AREA.
SOUTHEASTERLY WINDS WERE ALREADY DEVELOPING AT 17Z AND THE
INCREASED MOISTURE ADVECTION WILL AFFECT SOUTHEAST TEXAS LATER
TONIGHT. THE 14Z RUN OF THE HRRR FORECASTS THE BEST CHANCES FOR
FOG AFTER 06Z WEST OF THE INTERSTATE 45 CORRIDOR AND OVER THE
COASTAL COUNTIES. NAMBUFR MODEL SOUNDING FORECASTS SHOWS THE BEST
POTENTIAL BETWEEN ABOUT 09Z AND 15Z. ALTHOUGH THE FOG COULD LIFT
TO AN IFR DECK FROM 15Z TO 18Z...DID NOT THINK CHANCES FOR THIS
SCENARIO WERE GOOD. THE 12Z FORECAST LOOKED ON TRACK AND ONLY
MADE A FEW MINOR TWEAKS BY ADDING THE POSSIBILITY OF SHALLOW
DENSER FOG. ALSO LIKED THE PLACEMENT OF THE DENSER FOG CHANCES
OVER KSGR AND KLBX. KHOU WILL PROBABLY BE ON THE EDGE BUT WAS NOT
CONFIDENT ENOUGH TO ADD LOWER VISIBILITY AT THIS TIME.
40
&&
.PREV DISCUSSION... /ISSUED 952 AM CST TUE FEB 10 2015/
DISCUSSION...
CURRENT FCST IN GOOD SHAPE. VERY FEW CHANGES MADE FOR THE
UPDATE. 47
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 78 47 72 47 59 / 0 0 10 10 10
HOUSTON (IAH) 77 47 71 49 61 / 0 0 10 10 10
GALVESTON (GLS) 67 52 65 53 60 / 0 0 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...47
AVIATION/MARINE...40
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