Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 02/12/16
AREA FORECAST DISCUSSION
NWS NEW YORK NY
944 AM EST WED FEB 10 2016
.SYNOPSIS...
LOW PRESSURE WILL TRACK EAST OF MONTAUK TODAY...AND INTO THE NORTH
ATLANTIC TONIGHT. A COLD FRONT WILL PASS ON THURSDAY...FOLLOWED BY
WEAK HIGH PRESSURE ON FRIDAY. A STRONG ARCTIC COLD FRONT WILL
APPROACH FRIDAY NIGHT AND PASS THROUGH SATURDAY MORNING AS A
DEVELOPING OCEAN STORM PASSES BY TO THE SOUTHEAST. STRONG ARCTIC
HIGH PRESSURE WILL BUILD ACROSS LATER SATURDAY INTO SUNDAY
NIGHT...THEN RETREAT TO THE NORTHEAST MONDAY INTO MONDAY NIGHT.
A LOW PRESSURE SYSTEM WILL APPROACH ON TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
PER CURRENT RADAR AND EXTRAPOLATED TREND WHICH MATCHES HRRR FAIRLY
WELL...LIGHT SNOW SHOWERS SHOULD CONTINUE UNTIL ABOUT MIDDAY.
NO SIGNIFICANT ACCUMS EXPECTED.
A SHRTWV OVER SOUTHERN NJ AND DELMARVA NEAR DC WILL TRACK ENEWD
TODAY...AND IS LIKELY TO REMAIN JUST S OF LONG ISLAND. IF IT WERE
TO SKIRT LONG ISLAND...SOME PLACES...PARTICULARLY THE SOUTH SHORE
OF EASTERN LONG ISLAND...COULD SEE AN INCH OR TWO ACCUMULATION
LATE THIS MORNING INTO EARLY AFTERNOON.
THE LLVLS DRY OUT THIS AFTN WITH WLY FLOW...SO SNOW CHCS DECREASE
THRU THE DAY. THERE REMAINS SOME WEAK LIFT IN THE NEARLY SATURATED
H85-H7 REGION TNGT. THIS LEVEL WILL BE THERMALLY CONDUCIVE TO SNOW
PRODUCTION. AS A RESULT...INCLUDED FLURRIES IN THE FCST.
TEMPS GENERALLY A BLEND OF GUIDANCE...ALTHOUGH TRENDED HIGHS
CLOSER TO THE COLDER 00Z NAM 2M TEMPS DUE TO THE SNOW COVER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
H5 TROF AXIS...INCREASINGLY STEEP LAPSE RATES AND CYCLONIC FLOW
ALOFT SHOULD LEAD TO SCT TO NMRS SNOW SHWRS. SOME OF THESE COULD
BE LOCALLY HVY WITH THE NAM EVEN PRODUCING ABOUT 100 J/KG OF
SBCAPE. WENT WITH COVERAGE WORDING IN THE FCST. IN ADDITION TO THE
SNOW...WINDS SHOULD MIX DOWN ON UNIDIRECTIONAL FLOW ALOFT AND
PRODUCE GUSTS TO AROUND 30 MPH. BRIEF PERIODS OF HAZARDOUS TRAVEL
WILL THEREFORE BE POSSIBLE WHERE THE HEAVIER SNOW SHWRS OCCUR.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
BRISK NW FLOW AFTER COLD FROPA THU SHOULD PEAK DURING THE
EVENING...WITH POSSIBILITY OF WINDS REACHING ADVY CRITERIA IN
NYC AND ACROSS LONG ISLAND. THESE WINDS SHOULD DIMINISH LATE THU
NIGHT...BUT WILL STILL BE STRONG ENOUGH IN TANDEM WITH LOW TEMPS
IN THE SINGLE DIGITS INLAND AND TEENS NYC/COASTAL SECTIONS TO
PRODUCE WIND CHILLS AS LOW AS 0 TO 5 ABOVE.
FAIR ON FRI WITH HIGHS IN THE 20S...THEN AN ARCTIC COLD FRONT WILL
APPROACH FRI NIGHT...PASSING THROUGH LATE AT NIGHT OR EARLY SAT
MORNING. MEANWHILE A STRONG SHORTWAVE EMBEDDED IN THE INCREASINGLY
AMPLIFIED FLOW OVER THE EASTERN CONUS DURING THIS TIME SHOULD
INITIATE SFC CYCLOGENESIS ALONG A BAROCLINIC ZONE ALONG THE
CAROLINA COAST ON FRI...WITH THE LOW PASSING TO THE SE OF LONG
ISLAND LATE FRI NIGHT INTO EARLY SAT MORNING. THESE SYSTEMS HAVE
MADE A HABIT OF TRACKING CLOSER TO THE COAST THAN MODEL FCST...AND
SO INCREASED GUIDANCE POP A LITTLE TO BRING CHANCES TO NYC EAST
FOR SOME LIGHT ACCUMULATION.
THEN A QUICK SHOT OF VERY COLD AIR WILL OVERSPREAD THE AREA LATER
SAT INTO SUNDAY NIGHT. ECMWF/GFS AGREE ON H8 TEMPS AS COLD AS -29C
TO -30C APPROACHING LATE SAT NIGHT...WHICH SUPPORTS FCST LOW
TEMPS CLOSE TO ZERO IN NYC METRO AND LONG ISLAND...0 TO 5 BELOW
MOST ELSEWHERE...AND A LITTLE COLDER IN THE INTERIOR VALLEYS WELL
NORTH/WEST OF NYC. THESE TEMPS COMBINED WITH NW WINDS 10-20 MPH
WOULD PRODUCE WIND CHILLS OF 15 TO 20 BELOW OVER MOST OF THE
AREA...AND 25 BELOW ACROSS THE FAR INTERIOR.
THIS SHOT OF FRIGID AIR SHOULD BE SHORT LIVED AS THE ARCTIC HIGH
BUILDS OVERHEAD SUNDAY NIGHT...THEN PASSES EAST MON MORNING. WITH
THE HIGH OVERHEAD...FCST LOWS SUNDAY NIGHT OF 10-15 IN NYC AND
SINGLE DIGITS ELSEWHERE COULD END UP AT LEAST SEVERAL DEG COLDER
IF CLOUD COVER APPROACHING FROM THE WEST HOLDS OFF UNTIL MON.
HIGHS ON MON QUICKLY MODERATE TO 30-35.
OVERRUNNING THEN SETS UP MON AFTERNOON/NIGHT AHEAD OF AN
APPROACHING LOW PRESSURE SYSTEM...WITH POTENTIAL FOR SOME LIGHT
SNOW ACCUMULATION DURING THAT TIME...THEN POSSIBLY SOME FREEZING
RAIN/SLEET FROM NYC NORTH/WEST LATE MON NIGHT INTO TUE MORNING AS
TEMPS WARM ALOFT BUT A WEDGE OF LOW LEVEL COLDER AIR REMAINS.
TEMPS SHOULD WARM UP WELL INTO THE 40S TUE AFTERNOON...CHANGING
PRECIP TO ALL RAIN THROUGHOUT BY LATE MORNING OR MIDDAY.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
POCKETS OF LIGHT SNOW WILL CONTINUE TO PUSH THROUGH THE TERMINALS
THIS MORNING. CONDS LIFT TO VFR THROUGHOUT BY THIS AFTERNOON.
WEST WINDS INCREASE TO AROUND 15 KT WITH GUSTS TO 25 KT BY EARLY
AFTERNOON. AT THE NYC METRO TERMINALS...GUSTS CONTINUE THROUGH
TONIGHT WHILE GUSTS SUBSIDE AT THE REMAINDER OF THE TERMINALS.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: AMDS POSSIBLE FOR TIMING OF WIND SPEED
INCREASES AND FOR CHANGES IN FLIGHT CATEGORIES DUE TO SNOW.
KLGA FCSTER COMMENTS: AMDS POSSIBLE FOR TIMING OF WIND SPEED
INCREASES AND FOR CHANGES IN FLIGHT CATEGORIES DUE TO SNOW. A
FEW GUSTS MAY BE HIGHER THAN FORECAST THIS AFTERNOON.
KEWR FCSTER COMMENTS: AMDS POSSIBLE FOR TIMING OF WIND SPEED
INCREASES AND FOR CHANGES IN FLIGHT CATEGORIES DUE TO SNOW. A FEW
GUSTS MAY BE HIGHER THAN FORECAST THIS AFTERNOON.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: AMDS POSSIBLE FOR TIMING OF WIND SPEED
INCREASES AND FOR CHANGES IN FLIGHT CATEGORIES DUE TO SNOW. A FEW
GUSTS MAY BE HIGHER THAN FORECAST THIS AFTERNOON.
KHPN FCSTER COMMENTS: AMDS POSSIBLE FOR TIMING OF WIND SPEED
INCREASES AND FOR CHANGES IN FLIGHT CATEGORIES DUE TO SNOW. A FEW
GUSTS MAY BE HIGHER THAN FORECAST THIS AFTERNOON.
KISP FCSTER COMMENTS: AMDS POSSIBLE FOR TIMING OF WIND SPEED
INCREASES AND FOR CHANGES IN FLIGHT CATEGORIES DUE TO SNOW. A FEW
GUSTS MAY BE HIGHER THAN FORECAST THIS AFTERNOON.
.OUTLOOK FOR 15Z THU THROUGH SUN...
.THU...SLIGHT CHC -SHSN...OTHERWISE VFR. WNW GUSTS 25-30KT.
.FRI...VFR.
.SAT-SUN...VFR. NW GUSTS 20-30KT.
&&
.MARINE...
SCA COND THRU TNGT ON THE OCEAN. REISSUED FOR NY HARBOR WHERE
GUSTS SHOULD PEAK AROUND 25 KT LATE THIS AFTERNOON AND THIS
EVENING. ALL AREAS UNDER A GALE WATCH FOR THU AND THU NGT WITH
INCREASING WLY FLOW.
QUIET DAYTIME FRI WITH WEAK HIGH PRESSURE OVERHEAD...THEN SCA
CONDS LIKELY ON THE OCEAN FRI NIGHT...THEN GALES ON THE OCEAN SAT
INTO SAT NIGHT AND SCA CONDS ELSEWHERE AFTER AN ARCTIC COLD
FRONTAL PASSAGE. SCA CONDS ALL WATERS ON SUNDAY SHOULD QUIET DOWN
AGAIN SUNDAY NIGHT AS STRONG HIGH PRESSURE BUILDS OVERHEAD.
&&
.HYDROLOGY...
LGT AMTS OF SNOW CAN BE EXPECTED TODAY. SNOW SHWRS ON THU WILL
PRODUCE BASIN AVG QPF OF LESS THAN 1/10 OF AN INCH.
LIQUID EQUIVALENT QPF WITH AN ARCTIC COLD FRONT AND PASSING LOW TO
THE SE LATE FRI NIGHT INTO SAT MORNING SHOULD BE LESS THAN 1/4
INCH...WITH ANY HIGHER AMTS OVER SE CT AND ERN LONG ISLAND.
A LOW PRESSURE SYSTEM IMPACTING THE AREA FROM MON NIGHT INTO TUE
HAS POTENTIAL TO BRING SIGNIFICANT QPF OF OVER AN INCH...WITH MOST
OF THE PRECIP MON NIGHT FALLING AS LIGHT SNOW...THEN AS MODERATE
TO HEAVIER RAIN ON TUE.
&&
.TIDES/COASTAL FLOODING...
A GRADUAL DOWNWARD TREND IN SURGE AND ASTRONOMICAL TIDES EXPECTED
OVER THE NEXT COUPLE OF DAYS.
SURGE LOWERS FOR THE HIGH TIDE CYCLE THIS MORNING...WITH MINOR
COASTAL FLOODING FOR THE MORE VULNERABLE LOCALES OF THE LONG
ISLAND SOUTH SHORE BAYS...NY HARBOR...NE NJ...AND WESTERN LONG
ISLAND SOUND.
ASTRONOMICAL TIDES WILL CONTINUE TO LOWER TONIGHT...WITH ANY
BRIEF LOCALIZED MINOR IMPACTS LIKELY BEING RELEGATED TO THE SOUTH
SHORE BAYS OF LONG ISLAND.
&&
.CLIMATE...
WITH THE EXTREMELY COLD AIR MASS FORECAST SATURDAY INTO
SUNDAY...RECORD MINIMUMS AND RECORD LOW MAXIMUMS MAY BE REACHED.
HERE ARE THE RECORDS AND FORECASTS...
STATION......RECORD/FCST MINIMUM...RECORD LOW MAXIMUM/FCST HIGH
FOR 2/14 FOR 2/14
NYC...........2 (1916) / 2.............17 (1979) / 16
LGA...........1 (1979) / 3.............15 (1979) / 18
JFK...........4 (1979) / 2.............17 (1979) / 17
ISP...........7 (2015) / 0.............26 (1987) / 15
EWR...........0 (1979) / 0.............15 (1979) / 19
BDR...........3 (2015*) / -1.............18 (1979) / 15
*IN 1979 AS WELL
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...COASTAL FLOOD ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
CTZ009.
NY...COASTAL FLOOD ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
NYZ071-078-177.
COASTAL FLOOD ADVISORY UNTIL NOON EST TODAY FOR NYZ074-075-080-
178-179.
NJ...COASTAL FLOOD ADVISORY UNTIL NOON EST TODAY FOR NJZ006-106-108.
MARINE...GALE WATCH FROM THURSDAY MORNING THROUGH LATE THURSDAY NIGHT
FOR ANZ330-335-338-340-345-350-353-355.
SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 10 PM EST
THIS EVENING FOR ANZ338.
SMALL CRAFT ADVISORY UNTIL 6 AM EST THURSDAY FOR ANZ350-353-
355.
&&
$$
SYNOPSIS...JMC/GOODMAN
NEAR TERM...JMC/GOODMAN
SHORT TERM...JMC
LONG TERM...GOODMAN
AVIATION...MPS
MARINE...JMC/GOODMAN
HYDROLOGY...JMC/GOODMAN
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
751 AM EST WED FEB 10 2016
.SYNOPSIS...
LOW PRESSURE WILL TRACK EAST OF MONTAUK TODAY...AND INTO THE NORTH
ATLANTIC TONIGHT. A COLD FRONT WILL PASS ON THURSDAY...FOLLOWED BY
WEAK HIGH PRESSURE ON FRIDAY. A STRONG ARCTIC COLD FRONT WILL
APPROACH FRIDAY NIGHT AND PASS THROUGH SATURDAY MORNING AS A
DEVELOPING OCEAN STORM PASSES BY TO THE SOUTHEAST. STRONG ARCTIC
HIGH PRESSURE WILL BUILD ACROSS LATER SATURDAY INTO SUNDAY
NIGHT...THEN RETREAT TO THE NORTHEAST MONDAY INTO MONDAY NIGHT.
A LOW PRESSURE SYSTEM WILL APPROACH ON TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
PER CURRENT RADAR AND EXTRAPOLATED TREND WHICH MATCHES HRRR FAIRLY
WELL...LIGHT SNOW SHOWERS SHOULD CONTINUE UNTIL ABOUT MIDDAY.
NO SIGNIFICANT ACCUMS EXPECTED.
A SHRTWV OVER SOUTHERN NJ AND DELMARVA NEAR DC WILL TRACK ENEWD
TODAY...AND IS LIKELY TO REMAIN JUST S OF LONG ISLAND. IF IT WERE
TO SKIRT LONG ISLAND...SOME PLACES...PARTICULARLY THE SOUTH SHORE
OF EASTERN LONG ISLAND...COULD SEE AN INCH OR TWO ACCUMULATION
LATE THIS MORNING INTO EARLY AFTERNOON.
THE LLVLS DRY OUT THIS AFTN WITH WLY FLOW...SO SNOW CHCS DECREASE
THRU THE DAY. THERE REMAINS SOME WEAK LIFT IN THE NEARLY SATURATED
H85-H7 REGION TNGT. THIS LEVEL WILL BE THERMALLY CONDUCIVE TO SNOW
PRODUCTION. AS A RESULT...INCLUDED FLURRIES IN THE FCST.
TEMPS GENERALLY A BLEND OF GUIDANCE...ALTHOUGH TRENDED HIGHS
CLOSER TO THE COLDER 00Z NAM 2M TEMPS DUE TO THE SNOW COVER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
H5 TROF AXIS...INCREASINGLY STEEP LAPSE RATES AND CYCLONIC FLOW
ALOFT SHOULD LEAD TO SCT TO NMRS SNOW SHWRS. SOME OF THESE COULD
BE LOCALLY HVY WITH THE NAM EVEN PRODUCING ABOUT 100 J/KG OF
SBCAPE. WENT WITH COVERAGE WORDING IN THE FCST. IN ADDITION TO THE
SNOW...WINDS SHOULD MIX DOWN ON UNIDIRECTIONAL FLOW ALOFT AND
PRODUCE GUSTS TO AROUND 30 MPH. BRIEF PERIODS OF HAZARDOUS TRAVEL
WILL THEREFORE BE POSSIBLE WHERE THE HEAVIER SNOW SHWRS OCCUR.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
BRISK NW FLOW AFTER COLD FROPA THU SHOULD PEAK DURING THE
EVENING...WITH POSSIBILITY OF WINDS REACHING ADVY CRITERIA IN
NYC AND ACROSS LONG ISLAND. THESE WINDS SHOULD DIMINISH LATE THU
NIGHT...BUT WILL STILL BE STRONG ENOUGH IN TANDEM WITH LOW TEMPS
IN THE SINGLE DIGITS INLAND AND TEENS NYC/COASTAL SECTIONS TO
PRODUCE WIND CHILLS AS LOW AS 0 TO 5 ABOVE.
FAIR ON FRI WITH HIGHS IN THE 20S...THEN AN ARCTIC COLD FRONT WILL
APPROACH FRI NIGHT...PASSING THROUGH LATE AT NIGHT OR EARLY SAT
MORNING. MEANWHILE A STRONG SHORTWAVE EMBEDDED IN THE INCREASINGLY
AMPLIFIED FLOW OVER THE EASTERN CONUS DURING THIS TIME SHOULD
INITIATE SFC CYCLOGENESIS ALONG A BAROCLINIC ZONE ALONG THE
CAROLINA COAST ON FRI...WITH THE LOW PASSING TO THE SE OF LONG
ISLAND LATE FRI NIGHT INTO EARLY SAT MORNING. THESE SYSTEMS HAVE
MADE A HABIT OF TRACKING CLOSER TO THE COAST THAN MODEL FCST...AND
SO INCREASED GUIDANCE POP A LITTLE TO BRING CHANCES TO NYC EAST
FOR SOME LIGHT ACCUMULATION.
THEN A QUICK SHOT OF VERY COLD AIR WILL OVERSPREAD THE AREA LATER
SAT INTO SUNDAY NIGHT. ECMWF/GFS AGREE ON H8 TEMPS AS COLD AS -29C
TO -30C APPROACHING LATE SAT NIGHT...WHICH SUPPORTS FCST LOW
TEMPS CLOSE TO ZERO IN NYC METRO AND LONG ISLAND...0 TO 5 BELOW
MOST ELSEWHERE...AND A LITTLE COLDER IN THE INTERIOR VALLEYS WELL
NORTH/WEST OF NYC. THESE TEMPS COMBINED WITH NW WINDS 10-20 MPH
WOULD PRODUCE WIND CHILLS OF 15 TO 20 BELOW OVER MOST OF THE
AREA...AND 25 BELOW ACROSS THE FAR INTERIOR.
THIS SHOT OF FRIGID AIR SHOULD BE SHORT LIVED AS THE ARCTIC HIGH
BUILDS OVERHEAD SUNDAY NIGHT...THEN PASSES EAST MON MORNING. WITH
THE HIGH OVERHEAD...FCST LOWS SUNDAY NIGHT OF 10-15 IN NYC AND
SINGLE DIGITS ELSEWHERE COULD END UP AT LEAST SEVERAL DEG COLDER
IF CLOUD COVER APPROACHING FROM THE WEST HOLDS OFF UNTIL MON.
HIGHS ON MON QUICKLY MODERATE TO 30-35.
OVERRUNNING THEN SETS UP MON AFTERNOON/NIGHT AHEAD OF AN
APPROACHING LOW PRESSURE SYSTEM...WITH POTENTIAL FOR SOME LIGHT
SNOW ACCUMULATION DURING THAT TIME...THEN POSSIBLY SOME FREEZING
RAIN/SLEET FROM NYC NORTH/WEST LATE MON NIGHT INTO TUE MORNING AS
TEMPS WARM ALOFT BUT A WEDGE OF LOW LEVEL COLDER AIR REMAINS.
TEMPS SHOULD WARM UP WELL INTO THE 40S TUE AFTERNOON...CHANGING
PRECIP TO ALL RAIN THROUGHOUT BY LATE MORNING OR MIDDAY.
&&
.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...
A TROUGH OF LOW PRESSURE MOVES NORTH OF THE AREA THIS MORNING. LOW
PRESSURE REMAINS NORTHEAST OF THE AREA INTO WEDNESDAY NIGHT.
MAINLY MVFR OR VFR IN LIGHT SNOW AND DRIZZLE THIS MORNING. THERE
WILL BE SOME POCKETS OF IFR AS WELL. CONDITIONS SHOULD IMPROVE TO
VFR AROUND 15Z WITH PRECIPITATION COMING TO AN END. VSBY
RESTRICTIONS COULD FALL TO IFR IN AREAS OF SNOW.
WESTERLY WINDS 5 TO 10 KT THIS MORNING. GUSTS WILL DEVELOP AROUND
MIDDAY. AT THE NYC METRO TERMINALS GUSTS CONTINUE THROUGH TONIGHT
WHILE GUSTS SUBSIDE AT THE REMAINDER OF THE TERMINALS.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: AMENDMENTS POSSIBLE THIS MORNING FOR CHANGING
FLIGHT CATEGORIES DUE TO SNOW. A FEW GUSTS MAY BE HIGHER THAN
FORECAST THIS AFTERNOON.
KLGA FCSTER COMMENTS: AMENDMENTS POSSIBLE THIS MORNING FOR CHANGING
FLIGHT CATEGORIES DUE TO SNOW. A FEW GUSTS MAY BE HIGHER THAN
FORECAST THIS AFTERNOON.
KEWR FCSTER COMMENTS: AMENDMENTS POSSIBLE THIS MORNING FOR CHANGING
FLIGHT CATEGORIES DUE TO SNOW. A FEW GUSTS MAY BE HIGHER
THAN FORECAST THIS AFTERNOON.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: AMENDMENTS POSSIBLE THIS MORNING FOR CHANGING
FLIGHT CATEGORIES DUE TO SNOW. A FEW GUSTS MAY BE HIGHER
THAN FORECAST THIS AFTERNOON.
KHPN FCSTER COMMENTS: AMENDMENTS POSSIBLE THIS MORNING FOR CHANGING
FLIGHT CATEGORIES DUE TO SNOW. A FEW GUSTS MAY BE HIGHER THAN
FORECAST THIS AFTERNOON.
KISP FCSTER COMMENTS: AMENDMENTS POSSIBLE THIS MORNING FOR CHANGING
FLIGHT CATEGORIES DUE TO SNOW. A FEW GUSTS MAY BE HIGHER
THAN FORECAST THIS AFTERNOON.
.OUTLOOK FOR 12Z THU THROUGH SUN...
.LATE WED NIGHT...VFR. W GUSTS 20-25KT AT THE NYC METRO TERMINALS.
.THU...SLIGHT CHC -SHSN...OTHERWISE VFR. WNW GUSTS 25-30KT.
.FRI...VFR.
.SAT-SUN...VFR. NW GUSTS 20-30KT.
&&
.MARINE...
SCA COND THRU TNGT ON THE OCEAN. REISSUED FOR NY HARBOR WHERE
GUSTS SHOULD PEAK AROUND 25 KT LATE THIS AFTERNOON AND THIS
EVENING. ALL AREAS UNDER A GALE WATCH FOR THU AND THU NGT WITH
INCREASING WLY FLOW.
QUIET DAYTIME FRI WITH WEAK HIGH PRESSURE OVERHEAD...THEN SCA
CONDS LIKELY ON THE OCEAN FRI NIGHT...THEN GALES ON THE OCEAN SAT
INTO SAT NIGHT AND SCA CONDS ELSEWHERE AFTER AN ARCTIC COLD
FRONTAL PASSAGE. SCA CONDS ALL WATERS ON SUNDAY SHOULD QUIET DOWN
AGAIN SUNDAY NIGHT AS STRONG HIGH PRESSURE BUILDS OVERHEAD.
&&
.HYDROLOGY...
LGT AMTS OF SNOW CAN BE EXPECTED TODAY. SNOW SHWRS ON THU WILL
PRODUCE BASIN AVG QPF OF LESS THAN 1/10 OF AN INCH.
LIQUID EQUIVALENT QPF WITH AN ARCTIC COLD FRONT AND PASSING LOW TO
THE SE LATE FRI NIGHT INTO SAT MORNING SHOULD BE LESS THAN 1/4
INCH...WITH ANY HIGHER AMTS OVER SE CT AND ERN LONG ISLAND.
A LOW PRESSURE SYSTEM IMPACTING THE AREA FROM MON NIGHT INTO TUE
HAS POTENTIAL TO BRING SIGNIFICANT QPF OF OVER AN INCH...WITH MOST
OF THE PRECIP MON NIGHT FALLING AS LIGHT SNOW...THEN AS MODERATE
TO HEAVIER RAIN ON TUE.
&&
.TIDES/COASTAL FLOODING...
A GRADUAL DOWNWARD TREND IN SURGE AND ASTRONOMICAL TIDES EXPECTED
OVER THE NEXT COUPLE OF DAYS.
SURGE LOWERS FOR THE HIGH TIDE CYCLE THIS MORNING...WITH MINOR
COASTAL FLOODING FOR THE MORE VULNERABLE LOCALES OF THE LONG
ISLAND SOUTH SHORE BAYS...NY HARBOR...NE NJ...AND WESTERN LONG
ISLAND SOUND.
ASTRONOMICAL TIDES WILL CONTINUE TO LOWER TONIGHT...WITH ANY
BRIEF LOCALIZED MINOR IMPACTS LIKELY BEING RELEGATED TO THE SOUTH
SHORE BAYS OF LONG ISLAND.
&&
.CLIMATE...
WITH THE EXTREMELY COLD AIR MASS FORECAST SATURDAY INTO
SUNDAY...RECORD MINIMUMS AND RECORD LOW MAXIMUMS MAY BE REACHED.
HERE ARE THE RECORDS AND FORECASTS...
STATION......RECORD/FCST MINIMUM...RECORD LOW MAXIMUM/FCST HIGH
FOR 2/14 FOR 2/14
NYC...........2 (1916) / 2.............17 (1979) / 16
LGA...........1 (1979) / 3.............15 (1979) / 18
JFK...........4 (1979) / 2.............17 (1979) / 17
ISP...........7 (2015) / 0.............26 (1987) / 15
EWR...........0 (1979) / 0.............15 (1979) / 19
BDR...........3 (2015*) / -1.............18 (1979) / 15
*IN 1979 AS WELL
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...COASTAL FLOOD ADVISORY FROM 11 AM THIS MORNING TO 3 PM EST
THIS AFTERNOON FOR CTZ009.
NY...COASTAL FLOOD ADVISORY FROM 11 AM THIS MORNING TO 3 PM EST
THIS AFTERNOON FOR NYZ071-078-177.
COASTAL FLOOD ADVISORY UNTIL NOON EST TODAY FOR NYZ074-075-080-
178-179.
NJ...COASTAL FLOOD ADVISORY UNTIL NOON EST TODAY FOR NJZ006-106-108.
MARINE...GALE WATCH FROM THURSDAY MORNING THROUGH LATE THURSDAY NIGHT
FOR ANZ330-335-338-340-345-350-353-355.
SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 10 PM EST
THIS EVENING FOR ANZ338.
SMALL CRAFT ADVISORY UNTIL 6 AM EST THURSDAY FOR ANZ350-353-
355.
&&
$$
SYNOPSIS...JMC/GOODMAN
NEAR TERM...JMC/GOODMAN
SHORT TERM...JMC
LONG TERM...GOODMAN
AVIATION...BC
MARINE...JMC/GOODMAN
HYDROLOGY...JMC/GOODMAN
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS ALBANY NY
628 AM EST WED FEB 10 2016
.SYNOPSIS...
AN UPPER LEVEL TROUGH WILL PASS ACROSS THE REGION TODAY...BRINGING
SCATTERED TO NUMEROUS SNOW SHOWERS. SOME LAKE EFFECT SNOW SHOWERS
AND SQUALLS WILL REMAIN POSSIBLE THROUGH THURSDAY...ALONG WITH
COLDER TEMPERATURES. BITTERLY COLD TEMPERATURES AND WIND CHILLS
WILL FOLLOW IN THE WAKE OF AN ARCTIC FRONTAL PASSAGE LATE FRIDAY
INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LAKE EFFECT SNOW ADVISORY IN EFFECT FROM NOON EST WED-6 PM EST
THU FOR HERKIMER/HAMILTON COS...
FOR THIS UPDATE HAVE INCREASED POPS ACROSS THE EASTERN HALF OF THE
FA WHERE SEVERAL BANDS OF SNOW HAVE SET UP EARLY THIS MORNING.
EXPECT THESE BANDS TO DRIFT INTO WESTERN NEW ENGLAND AS THE
MORNING WEARS ON. ACCUMULATIONS WILL GENERALLY BE 1 TO PERHAPS 3
INCHES ACROSS THE HIGHER TERRAIN.
FOR TODAY...A DOUBLE BARREL AREA OF LOW PRESSURE WILL TRACK ACROSS
NORTHERN NEW YORK AND INTO NORTHERN NEW ENGLAND AS A COASTAL LOW
PASSES WELL SOUTH AND EAST OF CAPE COD. AT THE SAME TIME A LARGE
UPPER LEVEL TROUGH WILL DIG INTO THE EASTERN GREAT LAKES REGION.
THIS WILL RESULT IN SEVERAL BANDS OF MAINLY LIGHT SNOW TO MOVE
ACROSS MUCH OF THE FA THIS MORNING. ONCE THE SURFACE LOW PASSES
BY THERE WILL BE A TROUGH OF LOW PRESSURE EXTENDING BACK ACROSS
NORTHERN NEW YORK INTO THE GREAT LAKES. THIS FEATURE COMBINED WITH
CYCLONIC FLOW AND COLDER AIR FUNNELING ACROSS THE RELATIVELY WARM
WATERS OF LAKE ONTARIO WILL SET THE STAGE FOR SOME LAKE EFFECT
SNOW STARTING THIS AFTERNOON. HERKIMER AND HAMILTON COUNTIES CAN
GENERALLY EXPECT 1 TO 4 INCHES OF ACCUMULATION BY LATE TODAY.
HIGHS TODAY ARE GENERALLY EXPECTED TO REMAIN SLIGHTLY ABOVE NORMAL
RANGING FROM THE MID TO UPPER 20S NORTHWEST TO THE UPPER 30S
SOUTHEAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
LAKE EFFECT SNOW ADVISORY IN EFFECT FROM NOON EST WED-6 PM EST
THU FOR HERKIMER/HAMILTON COS...
FOR TONIGHT AND THURSDAY...A COLD CYCLONIC FLOW WILL REMAIN ACROSS
THE FA WITH A LAKE EFFECT SNOWBAND EXPECTED TO STRETCH ACROSS NORTHERN
HERKIMER AND HAMILTON COUNTIES THIS EVENING AND THEN SETTLE
SOUTHWARD INTO CENTRAL/SOUTHERN HERKIMER COUNTY...AND SW HAMILTON
COUNTY LATE TONIGHT INTO THURSDAY. TOTAL SNOWFALL ACCUMS BY LATE
THU IN THE ADVISORY AREA SHOULD RANGE FROM 4-8 INCHES OVER A 36+
HOUR PERIOD...WITH THE GREATEST AMTS ACROSS CENTRAL HERKIMER
COUNTY. ELSEWHERE...SOME SCATTERED SNOW SHOWERS WILL REMAIN
POSSIBLE WED NT INTO THU ACROSS THE CENTRAL/EASTERN MOHAWK
VALLEY...CAPITAL REGION...SCHOHARIE VALLEY AND BERKSHIRES. IN
THESE AREAS...ADDITIONAL COATINGS OF A DUSTING TO 2 INCHES
ARE POSSIBLE. EXPECT LOWS TONIGHT TO BE IN THE MAINLY IN THE TEENS
EXCEPT 5 TO 10 ABOVE ACROSS THE WESTERN ADIRONDACKS. HIGHS ON
THURSDAY ARE EXPECTED TO BE IN THE TEENS TO MID 20S...EXCEPT FOR
SOME SINGLE DIGITS ACROSS THE WESTERN ADIRONDACKS.
THURSDAY NIGHT THROUGH FRIDAY...THE LAKE EFFECT SNOW SHOULD
BECOME MULTIBAND AND SHIFT TO OUR WEST AS THE LOW LEVEL FLOW VEERS
THU NT. THEN ON FRI...WINDS WILL BE BACKING IN ADVANCE OF AN
APPROACHING ARCTIC FRONT. SO...SNOW SHOWERS WILL INCREASE ONCE
AGAIN FROM NW TO SE LATE FRI. IT WILL ALREADY BE COLD...WITH THU
NT/FRI AM MINS FALLING INTO THE SINGLE DIGITS ABOVE ZERO FOR MOST
AREAS...EXCEPT ZERO TO 5 BELOW ACROSS THE ADIRONDACKS. WIND CHILL
VALUES COULD APPROACH ADVISORY LEVELS IN PORTIONS OF THE
ADIRONDACKS TOWARD DAYBREAK FRI. THEN ON FRI...EXPECT MAX TEMPS TO
REACH THE 20S FOR MOST LOWER ELEVATIONS...AND TEENS ACROSS HIGHER
TERRAIN...COLDEST ACROSS THE WESTERN ADIRONDACKS.
FRIDAY NIGHT IS EXPECTED TO BE VERY COLD AS ARCTIC AIR FUNNELS
ACROSS THE FA. TEMPS ARE EXPECTED TO DROP TO 15 BELOW ZERO TO 15
ABOVE ZERO WITH WIND CHILLS ZERO TO 25 BELOW ZERO. THUS WIND CHILL
ADVISORYS MAY BE NEEDED.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
IN THE WAKE OF AN ARCTIC BOUNDARY...THE COLDEST AIR OF THE WINTER
SEASON WILL POUR INTO UPSTATE NY AND WESTERN NEW ENGLAND ON
SATURDAY...AS A PIECE OF THE POLAR VORTEX SWINGS ACROSS NEW YORK AND
NEW ENGLAND. THE CORE OF THIS FEATURE WILL MOVE DIRECTLY OVER THE
REGION...ALLOWING FOR A PERIOD OF BRUTALLY COLD AIR TO IMPACT THE
REGION. IN FACT...850 HPA TEMPS ARE SHOWN BY SEVERAL MODELS TO
DROP TO -30 TO -35 DEGREES C. THESE TEMPS COULD BE RECORD COLD
LEVELS FOR 850 HPA TEMPS AT ALBANY...AS THE COLDEST 850 HPA TEMP
MEASURED AT KALY IS -30 C ON A FEW PAST OCCASIONS.
TEMPS ON SATURDAY WILL BE STEADY/FALLING THE ENTIRE DAY. VALLEY
AREAS WILL SEE HIGHS IN THE MORNING NEAR 10...AND FALL THROUGH THE
SINGLE DIGITS...WITH HIGH TERRAIN AREAS BELOW ZERO THROUGH MUCH OF
THE DAY. IN ADDITION...GUSTY W-NW WINDS OF 10 TO 20 KTS WILL MAKE
FOR VERY COLD WIND CHILLS LEVELS. IT SHOULD BE DRY...HOWEVER...WITH
NO PRECIP EXPECTED...AND A MIX OF SUN AND CLOUDS.
FOR SAT NIGHT...THE MAIN STORY WILL BE THE BITTER COLD TEMPS AND
DANGEROUSLY COLD WIND CHILLS. LOWS TEMPS WILL FALL TO -5 TO
-15 DEGREES IN VALLEY AREAS...AND -10 TO -20 OVER THE HIGH TERRAIN.
THESE TEMPS ARE IMPRESSIVE CONSIDERING THERE WILL BE GUSTY WINDS ALL
NIGHT...AND SOME AREAS HAVE LITTLE SNOW PACK IN PLACE. ALONG WITH
THE GUSTY WINDS...WIND CHILL VALUES WILL BE AS LOW AS -20 TO -30
DEGREES IN VALLEY AREAS AND -30 TO -50 IN THE HIGHER ELEVATIONS.
WIND CHILL WARNINGS WILL LIKELY BE NEEDED FOR MUCH OF THE AREA...AND
WILL CONTINUE TO HIGHLIGHT THIS DANGER IN THE HWO STATEMENT.
TEMPS WILL RISE ON SUNDAY TO THE SINGLE DIGITS FOR HIGHS IN MOST
AREAS...ALONG WITH A GOOD DEAL OF SUNSHINE. ALTHOUGH IT WON/T BE
QUITE AS WINDY...THERE WILL STILL BE A BREEZE...AND WIND CHILL
VALUES WILL STILL BE RATHER LOW. WINDS MAY FINALLY START TO DIMINISH
ON SUNDAY NIGHT....AS SFC HIGH PRESSURE BUILD INTO THE AREA.
OVERNIGHT LOWS WILL RANGE BETWEEN 5 ABOVE TO 5 BELOW...EXPECT PARTS
OF THE WESTERN ADIRONDACKS WILL BE -5 TO -10 DEGREES.
TEMPS ALOFT WILL BE MODERATING VERY QUICKLY ON MONDAY...AS THE COLD
CORE SHIFTS AWAY FROM THE REGION. TEMPS LOOK TO REACH INTO THE 20S
FOR MOST AREAS FOR HIGHS. AT THIS POINT...THERE IS A SLIGHT TO LOW
CHC OF SOME LIGHT SNOW ON MONDAY DEPENDING ON THE EXACT SPEED/TRACK
OF A NORTHERN STREAM SYSTEM...BUT THIS IS STILL FAR FROM CERTAIN.
BETWEEN MONDAY NIGHT AND WEDNESDAY...THE FORECAST GETS MUCH MORE
UNCERTAIN...BUT THERE IS THE POTENTIAL FOR A HIGH IMPACT SYSTEM
DURING THIS TIME PERIOD. A SYSTEM MOVING THROUGH THE SOUTHERN
STREAM ACROSS THE DEEP SOUTH MAY START TO TURN UP THE EASTERN
SEABOARD...AND MAY MERGE/PHASE WITH THE NORTHERN STREAM SYSTEM
HEADING TOWARDS THE AREA. THE 00Z ECMWF/00Z GEFS/00Z GGEM ALL HINT
AT THE POTENTIAL FOR A SIGNIFICANT AMOUNT OF QPF WITH THE SYSTEM
WHICH COULD TRACK OVER/CLOSE TO THE REGION. MEANWHILE...THE 00Z GFS
HAS THESE SYSTEMS STAYING SEPARATE...AND THE SOUTHERN STREAM SYSTEM
GENERALLY REMAINING SOUTH/EAST OF THE REGION. IF IT OCCURS AS SHOWN
IN SOME OF THE GEFS MEMBERS OR LATEST ECMWF...P-TYPE WOULD BE A
MAJOR ISSUE WITH THIS SYSTEM...ESP CONSIDERING THE 00Z ECMWF
SOLUTION...WHICH COULD BRING SNOW/MIXED PRECIP/RAIN...AND
POTENTIALLY BACK TO ANY OR ALL OF THE ABOVE. THE STORM TRACK...WHICH
IS STILL VERY MUCH IN QUESTION...WILL DETERMINE THE EXACT P-TYPE AND
AMOUNTS...AND IT COULD WIND UP TRACKING OVER I-95 OR THE CONNECTICUT
RIVER VALLEY. HOWEVER...IT/S PROBABLY WORTH MENTIONING THAT THE
VERY COLD ARCTIC AIR ARRIVING THIS WEEKEND WILL BE TOUGH TO DISLODGE
AT LOW LEVELS...SO A PERIOD OF MIXED PRECIP IS CERTAINLY A
POSSIBILITY. DUE TO THIS STILL BEING DAYS 7-8 AND LARGE AMOUNTS OF
UNCERTAINTY REGARDING STORM TRACK/TIMING...WILL NOT INCLUDE IN HWO
JUST YET...BUT WILL CONTINUE TO CLOSELY MONITOR MODEL TRENDS. HAVE
GONE WITH HIGH CHC POPS FOR NOW BETWEEN MON NIGHT AND TUESDAY
NIGHT...AND WILL ALLOW TEMPS TO RISE ABOVE FREEZING BY TUESDAY AFTN
ACROSS MUCH OF THE AREA.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
WITH THE SLOW MOVING UPPER LEVEL TROUGH TO THE WEST OF THE
REGION...SOME ADDITIONAL LIGHT SNOW SHOWERS/FLURRIES WILL BE
POSSIBLE THROUGH THE REMAINDER OF THE OVERNIGHT HOURS AND INTO THE
DAY ON WEDNESDAY. LIMITED MOISTURE IN PLACE WILL KEEP THESE RATHER
SCATTERED IN COVERAGE...BRIEF IN DURATION...AND LIGHT IN
INTENSITY.
BASED ON THE CURRENT RADAR TRENDS AND 3KM HRRR GUIDANCE...WILL
INCLUDE TEMPO FOR MVFR CIGS/VSBYS DUE TO SNOW SHOWERS FOR THE
REMAINDER OF THE OVERNIGHT HOURS FOR ALL TAF SITES. WILL NOT
INCLUDE ANY IFR AT THIS TIME DUE TO LIMITED COVERAGE OF SNOW
SHOWER ACTIVITY...BUT CAN/T TOTALLY RULE IT OUT FOR KALB OR KPSF.
LIGHT OR CALM WINDS ARE EXPECTED FOR ALL SITES.
DURING THE DAY ON WEDNESDAY...FLYING CONDITIONS LOOK MAINLY
VFR WITH BKN-OVC CIGS AT 3500-4000 FT...ALTHOUGH SOME PERIODS OF
MVFR DUE TO SOMEWHAT LOWER CIGS OR PASSING SNOW SHOWERS CANNOT BE
RULED OUT. S-SW WINDS WILL BECOME WESTERLY AT 5-10 KTS BY THE MID
TO LATE MORNING HOURS. SKIES WILL START TO CLEAR OUT SOMEWHAT FOR
WEDNESDAY NIGHT...ALTHOUGH DEVELOPING LAKE EFFECT SNOW SHOWERS
WEST OF THE REGION WILL CONTINUE TO KEEP SCT-BKN CLOUDS AROUND.
OUTLOOK...
WEDNESDAY NIGHT THROUGH THURSDAY: MODERATE OPERATIONAL IMPACT.
SCATTERED -SHSN. BREEZY.
THURSDAY NIGHT TO FRIDAY: LOW OPERATIONAL IMPACT. ISOLATED -SHSN.
BREEZY.
FRIDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
SATURDAY THROUGH SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
TIDAL ISSUES ALONG THE ATLANTIC SEABOARD ARE RESULTING IN HIGHER
THAN NORMAL TIDES UP THE HUDSON RIVER. IT APPEARS POUGHKEEPSIE
WILL EXPERIENCE TIDAL IMPACTS WHICH MAY PERSIST THE NEXT COUPLE OF
DAYS. OTHERWISE...NO OTHER HYDROLOGICAL ISSUES ARE EXPECTED AT
THIS TIME.
WITH AN APPROACHING UPPER LEVEL TROUGH...SOME SNOW SHOWERS AND
FLURRIES ARE POSSIBLE THROUGH THURSDAY. TOTAL LIQUID EQUIVALENT
WILL BE VERY LIGHT...GENERALLY LESS THAN A TENTH OF AN INCH AT ANY
ONE LOCATION...PERHAPS A BIT HIGHER ACROSS THE WESTERN
ADIRONDACKS.
WITH COLDER TEMPERATURES ARRIVING BY LATER IN THE WEEK AND THE
UPCOMING WEEKEND...ICE COVER ON RIVERS AND LAKES WILL INCREASE IN
COVERAGE AND THICKNESS. TEMPERATURES SHOULD REMAIN COMPLETELY
BELOW FREEZING FROM WED NIGHT THROUGH THE REST OF 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.
&&
.CLIMATE...
BITTERLY COLD OVER THE WEEKEND WITH BELOW ZERO LOWS EXPECTED
SATURDAY NIGHT INTO SUNDAY MORNING ACROSS EAST CENTRAL NY AND
WESTERN NEW ENGLAND.
THE LAST TIME TEMPERATURES WERE BELOW ZERO WAS:
ALBANY NY: -9 DEGREES ON FEBRUARY 24, 2015
NOTE: THE LOW ON MARCH 6, 2015 WAS ZERO DEGREES
GLENS FALLS NY: -15 DEGREES ON MARCH 6, 2015
POUGHKEEPSIE NY: -2 DEGREES ON MARCH 6, 2015
BENNINGTON VT: -11 DEGREES ON MARCH 6, 2015
PITTSFIELD MA: -4 DEGREES ON MARCH 7, 2015
FEBRUARY 13TH...RECORD LOW MAXIMUM TEMPERATURES...
ALBANY: 8 DEGREES SET IN 1899
GLENS FALLS: 4 DEGREES SET IN 1979
POUGHKEEPSIE: 13 DEGREES SET IN 1979
FEBRUARY 14TH...RECORD LOWS...
ALBANY: -10 DEGREES SET IN 1987
GLENS FALLS: -24 DEGREES SET IN 2003
POUGHKEEPSIE: -14 DEGREES SET IN 1979
FEBRUARY 14TH...RECORD LOW MAXIMUM TEMPERATURES...
ALBANY: 4 DEGREES SET IN 1916
GLENS FALLS: 4 DEGREES SET IN 1987
POUGHKEEPSIE: 15 DEGREES SET IN 1979
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...LAKE EFFECT SNOW ADVISORY FROM NOON TODAY TO 6 PM EST THURSDAY
FOR NYZ032-033-038.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...KL/11
NEAR TERM...11
SHORT TERM...KL/11
LONG TERM...FRUGIS
AVIATION...FRUGIS
HYDROLOGY...KL/11
CLIMATE...
AREA FORECAST DISCUSSION
NWS ALBANY NY
337 AM EST WED FEB 10 2016
.SYNOPSIS...
AN UPPER LEVEL TROUGH WILL PASS ACROSS THE REGION TODAY...BRINGING
SCATTERED TO NUMEROUS SNOW SHOWERS. SOME LAKE EFFECT SNOW SHOWERS
AND SQUALLS WILL REMAIN POSSIBLE THROUGH THURSDAY...ALONG WITH
COLDER TEMPERATURES. BITTERLY COLD TEMPERATURES AND WIND CHILLS
WILL FOLLOW IN THE WAKE OF AN ARCTIC FRONTAL PASSAGE LATE FRIDAY
INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LAKE EFFECT SNOW ADVISORY IN EFFECT FROM NOON EST WED-6 PM EST
THU FOR HERKIMER/HAMILTON COS...
FOR TODAY...A DOUBLE BARREL AREA OF LOW PRESSURE WILL TRACK ACROSS
NORTHERN NEW YORK AND INTO NORTHERN NEW ENGLAND AS A COASTAL LOW
PASSES WELL SOUTH AND EAST OF CAPE COD. AT THE SAME TIME A LARGE
UPPER LEVEL TROUGH WILL DIG INTO THE EASTERN GREAT LAKES REGION.
THIS WILL RESULT IN SEVERAL BANDS OF MAINLY LIGHT SNOW TO MOVE
ACROSS MUCH OF THE FA THIS MORNING. MOST LOCATIONS CAN EXPECT A
DUSTING TO PERHAPS TWO INCHES OF SNOWFALL ACCUMULATION. ONCE THE
SURFACE LOW PASSES BY THERE WILL BE A TROUGH OF LOW PRESSURE
EXTENDING BACK ACROSS NORTHERN NEW YORK INTO THE GREAT LAKES. THIS
FEATURE COMBINED WITH CYCLONIC FLOW AND COLDER AIR FUNNELING
ACROSS THE RELATIVELY WARM WATERS OF LAKE ONTARIO WILL SET THE
STAGE FOR SOME LAKE EFFECT SNOW STARTING THIS AFTERNOON. HERKIMER
AND HAMILTON COUNTIES CAN GENERALLY EXPECT 1 TO 4 INCHES OF
ACCUMULATION BY LATE TODAY. HIGHS TODAY ARE GENERALLY EXPECTED TO
REMAIN SLIGHTLY ABOVE NORMAL RANGING FROM THE MID TO UPPER 20S
NORTHWEST TO THE UPPER 30S SOUTHEAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
LAKE EFFECT SNOW ADVISORY IN EFFECT FROM NOON EST WED-6 PM EST
THU FOR HERKIMER/HAMILTON COS...
FOR TONIGHT AND THURSDAY...A COLD CYCLONIC FLOW WILL REMAIN ACROSS
THE FA WITH A LAKE EFFECT SNOWBAND EXPECTED TO STRETCH ACROSS NORTHERN
HERKIMER AND HAMILTON COUNTIES THIS EVENING AND THEN SETTLE
SOUTHWARD INTO CENTRAL/SOUTHERN HERKIMER COUNTY...AND SW HAMILTON
COUNTY LATE TONIGHT INTO THURSDAY. TOTAL SNOWFALL ACCUMS BY LATE
THU IN THE ADVISORY AREA SHOULD RANGE FROM 4-8 INCHES OVER A 36+
HOUR PERIOD...WITH THE GREATEST AMTS ACROSS CENTRAL HERKIMER
COUNTY. ELSEWHERE...SOME SCATTERED SNOW SHOWERS WILL REMAIN
POSSIBLE WED NT INTO THU ACROSS THE CENTRAL/EASTERN MOHAWK
VALLEY...CAPITAL REGION...SCHOHARIE VALLEY AND BERKSHIRES. IN
THESE AREAS...ADDITIONAL COATINGS OF A DUSTING TO 2 INCHES
ARE POSSIBLE. EXPECT LOWS TONIGHT TO BE IN THE MAINLY IN THE TEENS
EXCEPT 5 TO 10 ABOVE ACROSS THE WESTERN ADIRONDACKS. HIGHS ON
THURSDAY ARE EXPECTED TO BE IN THE TEENS TO MID 20S...EXCEPT FOR
SOME SINGLE DIGITS ACROSS THE WESTERN ADIRONDACKS.
THURSDAY NIGHT THROUGH FRIDAY...THE LAKE EFFECT SNOW SHOULD
BECOME MULTIBAND AND SHIFT TO OUR WEST AS THE LOW LEVEL FLOW VEERS
THU NT. THEN ON FRI...WINDS WILL BE BACKING IN ADVANCE OF AN
APPROACHING ARCTIC FRONT. SO...SNOW SHOWERS WILL INCREASE ONCE
AGAIN FROM NW TO SE LATE FRI. IT WILL ALREADY BE COLD...WITH THU
NT/FRI AM MINS FALLING INTO THE SINGLE DIGITS ABOVE ZERO FOR MOST
AREAS...EXCEPT ZERO TO 5 BELOW ACROSS THE ADIRONDACKS. WIND CHILL
VALUES COULD APPROACH ADVISORY LEVELS IN PORTIONS OF THE
ADIRONDACKS TOWARD DAYBREAK FRI. THEN ON FRI...EXPECT MAX TEMPS TO
REACH THE 20S FOR MOST LOWER ELEVATIONS...AND TEENS ACROSS HIGHER
TERRAIN...COLDEST ACROSS THE WESTERN ADIRONDACKS.
FRIDAY NIGHT IS EXPECTED TO BE VERY COLD AS ARCTIC AIR FUNNELS
ACROSS THE FA. TEMPS ARE EXPECTED TO DROP TO 15 BELOW ZERO TO 15
ABOVE ZERO WITH WIND CHILLS ZERO TO 25 BELOW ZERO. THUS WIND CHILL
ADVISORYS MAY BE NEEDED.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
IN THE WAKE OF AN ARCTIC BOUNDARY...THE COLDEST AIR OF THE WINTER
SEASON WILL POUR INTO UPSTATE NY AND WESTERN NEW ENGLAND ON
SATURDAY...AS A PIECE OF THE POLAR VORTEX SWINGS ACROSS NEW YORK AND
NEW ENGLAND. THE CORE OF THIS FEATURE WILL MOVE DIRECTLY OVER THE
REGION...ALLOWING FOR A PERIOD OF BRUTALLY COLD AIR TO IMPACT THE
REGION. IN FACT...850 HPA TEMPS ARE SHOWN BY SEVERAL MODELS TO
DROP TO -30 TO -35 DEGREES C. THESE TEMPS COULD BE RECORD COLD
LEVELS FOR 850 HPA TEMPS AT ALBANY...AS THE COLDEST 850 HPA TEMP
MEASURED AT KALY IS -30 C ON A FEW PAST OCCASIONS.
TEMPS ON SATURDAY WILL BE STEADY/FALLING THE ENTIRE DAY. VALLEY
AREAS WILL SEE HIGHS IN THE MORNING NEAR 10...AND FALL THROUGH THE
SINGLE DIGITS...WITH HIGH TERRAIN AREAS BELOW ZERO THROUGH MUCH OF
THE DAY. IN ADDITION...GUSTY W-NW WINDS OF 10 TO 20 KTS WILL MAKE
FOR VERY COLD WIND CHILLS LEVELS. IT SHOULD BE DRY...HOWEVER...WITH
NO PRECIP EXPECTED...AND A MIX OF SUN AND CLOUDS.
FOR SAT NIGHT...THE MAIN STORY WILL BE THE BITTER COLD TEMPS AND
DANGEROUSLY COLD WIND CHILLS. LOWS TEMPS WILL FALL TO -5 TO
-15 DEGREES IN VALLEY AREAS...AND -10 TO -20 OVER THE HIGH TERRAIN.
THESE TEMPS ARE IMPRESSIVE CONSIDERING THERE WILL BE GUSTY WINDS ALL
NIGHT...AND SOME AREAS HAVE LITTLE SNOW PACK IN PLACE. ALONG WITH
THE GUSTY WINDS...WIND CHILL VALUES WILL BE AS LOW AS -20 TO -30
DEGREES IN VALLEY AREAS AND -30 TO -50 IN THE HIGHER ELEVATIONS.
WIND CHILL WARNINGS WILL LIKELY BE NEEDED FOR MUCH OF THE AREA...AND
WILL CONTINUE TO HIGHLIGHT THIS DANGER IN THE HWO STATEMENT.
TEMPS WILL RISE ON SUNDAY TO THE SINGLE DIGITS FOR HIGHS IN MOST
AREAS...ALONG WITH A GOOD DEAL OF SUNSHINE. ALTHOUGH IT WON/T BE
QUITE AS WINDY...THERE WILL STILL BE A BREEZE...AND WIND CHILL
VALUES WILL STILL BE RATHER LOW. WINDS MAY FINALLY START TO DIMINISH
ON SUNDAY NIGHT....AS SFC HIGH PRESSURE BUILD INTO THE AREA.
OVERNIGHT LOWS WILL RANGE BETWEEN 5 ABOVE TO 5 BELOW...EXPECT PARTS
OF THE WESTERN ADIRONDACKS WILL BE -5 TO -10 DEGREES.
TEMPS ALOFT WILL BE MODERATING VERY QUICKLY ON MONDAY...AS THE COLD
CORE SHIFTS AWAY FROM THE REGION. TEMPS LOOK TO REACH INTO THE 20S
FOR MOST AREAS FOR HIGHS. AT THIS POINT...THERE IS A SLIGHT TO LOW
CHC OF SOME LIGHT SNOW ON MONDAY DEPENDING ON THE EXACT SPEED/TRACK
OF A NORTHERN STREAM SYSTEM...BUT THIS IS STILL FAR FROM CERTAIN.
BETWEEN MONDAY NIGHT AND WEDNESDAY...THE FORECAST GETS MUCH MORE
UNCERTAIN...BUT THERE IS THE POTENTIAL FOR A HIGH IMPACT SYSTEM
DURING THIS TIME PERIOD. A SYSTEM MOVING THROUGH THE SOUTHERN
STREAM ACROSS THE DEEP SOUTH MAY START TO TURN UP THE EASTERN
SEABOARD...AND MAY MERGE/PHASE WITH THE NORTHERN STREAM SYSTEM
HEADING TOWARDS THE AREA. THE 00Z ECMWF/00Z GEFS/00Z GGEM ALL HINT
AT THE POTENTIAL FOR A SIGNIFICANT AMOUNT OF QPF WITH THE SYSTEM
WHICH COULD TRACK OVER/CLOSE TO THE REGION. MEANWHILE...THE 00Z GFS
HAS THESE SYSTEMS STAYING SEPARATE...AND THE SOUTHERN STREAM SYSTEM
GENERALLY REMAINING SOUTH/EAST OF THE REGION. IF IT OCCURS AS SHOWN
IN SOME OF THE GEFS MEMBERS OR LATEST ECMWF...P-TYPE WOULD BE A
MAJOR ISSUE WITH THIS SYSTEM...ESP CONSIDERING THE 00Z ECMWF
SOLUTION...WHICH COULD BRING SNOW/MIXED PRECIP/RAIN...AND
POTENTIALLY BACK TO ANY OR ALL OF THE ABOVE. THE STORM TRACK...WHICH
IS STILL VERY MUCH IN QUESTION...WILL DETERMINE THE EXACT P-TYPE AND
AMOUNTS...AND IT COULD WIND UP TRACKING OVER I-95 OR THE CONNECTICUT
RIVER VALLEY. HOWEVER...IT/S PROBABLY WORTH MENTIONING THAT THE
VERY COLD ARCTIC AIR ARRIVING THIS WEEKEND WILL BE TOUGH TO DISLODGE
AT LOW LEVELS...SO A PERIOD OF MIXED PRECIP IS CERTAINLY A
POSSIBILITY. DUE TO THIS STILL BEING DAYS 7-8 AND LARGE AMOUNTS OF
UNCERTAINTY REGARDING STORM TRACK/TIMING...WILL NOT INCLUDE IN HWO
JUST YET...BUT WILL CONTINUE TO CLOSELY MONITOR MODEL TRENDS. HAVE
GONE WITH HIGH CHC POPS FOR NOW BETWEEN MON NIGHT AND TUESDAY
NIGHT...AND WILL ALLOW TEMPS TO RISE ABOVE FREEZING BY TUESDAY AFTN
ACROSS MUCH OF THE AREA.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
WITH THE SLOW MOVING UPPER LEVEL TROUGH TO THE WEST OF THE
REGION...SOME ADDITIONAL LIGHT SNOW SHOWERS/FLURRIES WILL BE
POSSIBLE THROUGH THE REMAINDER OF THE OVERNIGHT HOURS AND INTO THE
DAY ON WEDNESDAY. LIMITED MOISTURE IN PLACE WILL KEEP THESE RATHER
SCATTERED IN COVERAGE...BRIEF IN DURATION...AND LIGHT IN
INTENSITY.
BASED ON THE CURRENT RADAR TRENDS AND 3KM HRRR GUIDANCE...WILL
INCLUDE TEMPO FOR MVFR CIGS/VSBYS DUE TO SNOW SHOWERS FOR THE
REMAINDER OF THE OVERNIGHT HOURS FOR ALL TAF SITES. WILL NOT
INCLUDE ANY IFR AT THIS TIME DUE TO LIMITED COVERAGE OF SNOW
SHOWER ACTIVITY...BUT CAN/T TOTALLY RULE IT OUT FOR KALB OR KPSF.
LIGHT OR CALM WINDS ARE EXPECTED FOR ALL SITES.
DURING THE DAY ON WEDNESDAY...FLYING CONDITIONS LOOK MAINLY
VFR WITH BKN-OVC CIGS AT 3500-4000 FT...ALTHOUGH SOME PERIODS OF
MVFR DUE TO SOMEWHAT LOWER CIGS OR PASSING SNOW SHOWERS CANNOT BE
RULED OUT. S-SW WINDS WILL BECOME WESTERLY AT 5-10 KTS BY THE MID
TO LATE MORNING HOURS. SKIES WILL START TO CLEAR OUT SOMEWHAT FOR
WEDNESDAY NIGHT...ALTHOUGH DEVELOPING LAKE EFFECT SNOW SHOWERS
WEST OF THE REGION WILL CONTINUE TO KEEP SCT-BKN CLOUDS AROUND.
OUTLOOK...
WEDNESDAY NIGHT THROUGH THURSDAY: MODERATE OPERATIONAL IMPACT.
SCATTERED -SHSN. BREEZY.
THURSDAY NIGHT TO FRIDAY: LOW OPERATIONAL IMPACT. ISOLATED -SHSN.
BREEZY.
FRIDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
SATURDAY THROUGH SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
TIDAL ISSUES ALONG THE ATLANTIC SEABOARD ARE RESULTING IN HIGHER
THAN NORMAL TIDES UP THE HUDSON RIVER. IT APPEARS POUGHKEEPSIE
WILL EXPERIENCE TIDAL IMPACTS WHICH MAY PERSIST THE NEXT COUPLE OF
DAYS. OTHERWISE...NO OTHER HYDROLOGICAL ISSUES ARE EXPECTED AT
THIS TIME.
WITH AN APPROACHING UPPER LEVEL TROUGH...SOME SNOW SHOWERS AND
FLURRIES ARE POSSIBLE THROUGH THURSDAY. TOTAL LIQUID EQUIVALENT
WILL BE VERY LIGHT...GENERALLY LESS THAN A TENTH OF AN INCH AT ANY
ONE LOCATION...PERHAPS A BIT HIGHER ACROSS THE WESTERN
ADIRONDACKS.
WITH COLDER TEMPERATURES ARRIVING BY LATER IN THE WEEK AND THE
UPCOMING WEEKEND...ICE COVER ON RIVERS AND LAKES WILL INCREASE IN
COVERAGE AND THICKNESS. TEMPERATURES SHOULD REMAIN COMPLETELY
BELOW FREEZING FROM WED NIGHT THROUGH THE REST OF 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.
&&
.CLIMATE...
BITTERLY COLD OVER THE WEEKEND WITH BELOW ZERO LOWS EXPECTED
SATURDAY NIGHT INTO SUNDAY MORNING ACROSS EAST CENTRAL NY AND
WESTERN NEW ENGLAND.
THE LAST TIME TEMPERATURES WERE BELOW ZERO WAS:
ALBANY NY: -9 DEGREES ON FEBRUARY 24, 2015
NOTE: THE LOW ON MARCH 6, 2015 WAS ZERO DEGREES
GLENS FALLS NY: -15 DEGREES ON MARCH 6, 2015
POUGHKEEPSIE NY: -2 DEGREES ON MARCH 6, 2015
BENNINGTON VT: -11 DEGREES ON MARCH 6, 2015
PITTSFIELD MA: -4 DEGREES ON MARCH 7, 2015
FEBRUARY 13TH...RECORD LOW MAXIMUM TEMPERATURES...
ALBANY: 8 DEGREES SET IN 1899
GLENS FALLS: 4 DEGREES SET IN 1979
POUGHKEEPSIE: 13 DEGREES SET IN 1979
FEBRUARY 14TH...RECORD LOWS...
ALBANY: -10 DEGREES SET IN 1987
GLENS FALLS: -24 DEGREES SET IN 2003
POUGHKEEPSIE: -14 DEGREES SET IN 1979
FEBRUARY 14TH...RECORD LOW MAXIMUM TEMPERATURES...
ALBANY: 4 DEGREES SET IN 1916
GLENS FALLS: 4 DEGREES SET IN 1987
POUGHKEEPSIE: 15 DEGREES SET IN 1979
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...LAKE EFFECT SNOW ADVISORY FROM NOON TODAY TO 6 PM EST THURSDAY
FOR NYZ032-033-038.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...KL/11
NEAR TERM...11
SHORT TERM...KL/11
LONG TERM...FRUGIS
AVIATION...FRUGIS
HYDROLOGY...11/KL
CLIMATE...
AREA FORECAST DISCUSSION
NWS ALBANY NY
1238 AM EST WED FEB 10 2016
.SYNOPSIS...
AN UPPER LEVEL TROUGH WILL APPROACH LATE TONIGHT...AND
PASS ACROSS THE REGION WEDNESDAY...BRINGING SCATTERED TO NUMEROUS
SNOW SHOWERS. SOME LAKE EFFECT SNOW SHOWERS AND SQUALLS WILL REMAIN
POSSIBLE THROUGH THURSDAY...ALONG WITH COLDER TEMPERATURES.
BITTERLY COLD TEMPERATURES AND WIND CHILLS WILL FOLLOW IN THE WAKE
OF AN ARCTIC FRONTAL PASSAGE LATE FRIDAY INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1225 AM EST...SNOW SHOWERS ASSOCIATED WITH A LOW PRESSURE
SYSTEM OVER NORTHERN NEW YORK WERE MOVING EAST FROM THE MOHAWK
VALLEY AND SCHOHARIE VALLEY.
EXPECT SCATTERED/NUMEROUS SNOW SHOWERS TO CONTINUE THROUGHOUT THE
OVERNIGHT AS THE UPPER LOW MOVES CLOSER. A SLIGHTLY MORE
SIGNIFICANT DISTURBANCE MIGHT ENHANCE THE ACTIVITY TOWARD
DAYBREAK.
EITHER WAY LOOK FOR AROUND AN INCH OR TWO OF NEW SNOWFALL
OVERNIGHT IN AREAS WHERE THE SNOW SHOWERS PERSIST THE LONGEST WITH
A DUSTING TO AN INCH ELSEWHERE.
TEMPERATURES LOOK AS IF THEY HAVE BOTTOMED OUT FOR THE NIGHT AS
WE UNDERGO SOME WARM AIR ADVECTION. LOOK FOR LOWS GENERALLY IN THE
LOWER TO MID 20S VALLEYS...UPPER TEENS TO 20 ACROSS THE HIGHER
TERRAIN.
THE WIND WILL BE LIGHT AND VARIABLE OVERNIGHT...BECOMING SOUTHERLY
TOWARD DAYBREAK BUT GENERALLY BELOW 10 MPH.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY/...
LAKE EFFECT SNOW ADVISORY IN EFFECT FROM NOON EST WED-6 PM EST
THU FOR HERKIMER/HAMILTON COS...
WEDNESDAY...THE AFOREMENTIONED INVERTED TROUGH/OCCLUDED FRONT WILL
SLOWLY MOVE EAST ACROSS THE REGION IN THE MORNING. A BAND OF LIGHT
TO MODERATE SNOW WILL LIKELY PRECEDE AND ACCOMPANY THIS FEATURE.
AN ADDITIONAL INCH WILL BE POSSIBLE IN THE MORNING FOR AREAS FROM
ABOUT THE HUDSON RIVER WEST...WITH AN ADDITIONAL 1-3 INCHES TO THE
EAST. IT IS POSSIBLE THAT SOME LOCALLY HIGHER AMTS OCCUR ACROSS
PORTIONS OF THE BERKSHIRES AND LITCHFIELD HILLS...WHERE A BIT MORE
LOW LEVEL MOISTURE MAY BE INFUSED INTO THIS SYSTEM.
THEN...AFTER THIS BOUNDARY SHIFTS EAST OF THE REGION BY LATE
MORNING...THE MAIN UPPER LEVEL TROUGH WILL SWING EAST DURING THE
AFTERNOON. TEMPS ALOFT WILL BE QUITE COLD...WITH H500 TEMPS
DROPPING TO AROUND OR COLDER THAN -35 C. WEST WINDS IN THE WAKE OF
THE BOUNDARY WILL INCREASE SOME LOW LEVEL MOISTURE FROM THE
LAKES...AND LOW/MID LEVEL LAPSE RATES WILL BECOME RATHER STEEP.
SO...EXPECT SCATTERED TO NUMEROUS SNOW SHOWERS AND FLURRIES TO
DEVELOP IN THE AFTERNOON...WITH A FEW EMBEDDED HEAVIER SQUALLS
POSSIBLE...ESP WITH SOME INCREASED FORCING FROM THE PASSAGE OF THE
UPPER LEVEL FEATURE. THE SNOW SHOWERS/SQUALLS MAY BE MORE
PERSISTENT ACROSS UPSLOPE AREAS OF THE BERKSHIRES...SOUTHERN VT
AND LITCHFIELD HILLS...WHERE AN ADDITIONAL 1-2 INCHES COULD OCCUR
IN SOME AREAS.
ALSO...WITH THE REMNANT MID/UPPER LEVEL LOW TRACKING OVER THE
REGION...NORTHERN AREAS MAY ALSO BECOME INFLUENCED BY SOME MID
LEVEL DEFORMATION. THIS MAY ENHANCE EXISTING LAKE
ENHANCED/UPSLOPE SNOW SHOWERS/BANDS ACROSS NORTHERN HERKIMER AND
HAMILTON COS IN THE AFTERNOON...WHERE 2-4 INCHES OF SNOW COULD
OCCUR. THE LAKE EFFECT SNOW ADVISORY HAS BEEN ISSUED...AND STARTS
NOONTIME WEDNESDAY TO ACCOUNT FOR THIS INITIAL HYBRID
SNOWFALL...BEFORE IT TRANSITIONS TO MORE OF A PURE LAKE EFFECT
EVENT FOR WED NT-THU.
MAX TEMPS THU MAY ACTUALLY BRIEFLY SPIKE INTO THE MID 30S IN SOME
VALLEY AREAS DUE TO DEEP MIXING IN THE WAKE OF THE MORNING
BOUNDARY...WITH MAINLY 20S TO LOWER 30S ELSEWHERE. WINDS WILL
BECOME GUSTY AT TIMES IN THE AFTERNOON FROM THE WEST AT 15-25
MPH...WITH SOME STRONGER GUSTS POSSIBLE...ESP WITH ANY SNOW
SHOWERS.
WED NT-THU...IN THE WAKE OF THE MAIN UPPER LEVEL TROUGH
PASSAGE...A COLD NORTHWEST LOW LEVEL FLOW WILL DOMINATE. IT
APPEARS THAT A LAKE EFFECT SNOWBAND MAY BE ONGOING ACROSS NORTHERN
HERKIMER AND HAMILTON COS WED EVENING...BEFORE SETTLING SOUTHWARD
INTO CENTRAL/SOUTHERN HERKIMER CO...AND SW HAMILTON CO LATER AT
NIGHT INTO THURSDAY. TOTAL SNOWFALL ACCUMS BY LATE THU IN THE
ADVISORY AREA SHOULD RANGE FROM 4-8 INCHES OVER A 36+ HOUR
PERIOD...WITH THE GREATEST AMTS ACROSS CENTRAL HERKIMER CO.
ELSEWHERE...SOME SCATTERED SNOW SHOWERS WILL REMAIN POSSIBLE WED
NT INTO THU...WITH THE POSSIBILITY OF SOME FILAMENTS BREAKING OFF
THE MAIN LAKE EFFECT SNOWBAND INTO THE CENTRAL/EASTERN MOHAWK
VALLEY...CAPITAL REGION...SCHOHARIE VALLEY AND BERKSHIRES. IN
THESE AREAS...ADDITIONAL COATINGS TO 2 INCHES POSSIBLE IN SOME OF
THESE AREAS.
THU NT-FRI...LAKE EFFECT SNOW SHOULD BECOME MULTIBAND AND SHIFT TO
OUR WEST AS THE LOW LEVEL FLOW VEERS THU NT. THEN ON FRI...WINDS
WILL BE BACKING IN ADVANCE OF AN APPROACHING ARCTIC FRONT.
SO...SNOW SHOWERS WILL INCREASE ONCE AGAIN FROM NW TO SE LATE FRI.
IT WILL ALREADY BE COLD...WITH THU NT/FRI AM MINS FALLING INTO THE
SINGLE DIGITS ABOVE ZERO FOR MOST AREAS...EXCEPT ZERO TO 5 BELOW
ACROSS THE ADIRONDACKS. WIND CHILL VALUES COULD APPROACH ADVISORY
LEVELS IN PORTIONS OF THE ADIRONDACKS TOWARD DAYBREAK FRI. THEN
ON FRI...EXPECT MAX TEMPS TO REACH THE 20S FOR MOST LOWER
ELEVATIONS...AND TEENS ACROSS HIGHER TERRAIN...COLDEST ACROSS THE
WESTERN ADIRONDACKS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE EXTENDED STARTS OUT WITH COLDEST AIR MASS OF THE WINTER
SEASON WORKING OVER THE REGION FRIDAY NIGHT VIA A STRONG
COLD FRONT. THIS FEATURE COULD TRIGGER LOCALIZED SNOW
SQUALLS...MAINLY FROM THE CAPITAL REGION NORTHWARD.
LOWS WILL BE IN THE TEENS FROM THE CAPITAL REGION SOUTHWARD...
SINGLE NUMBERS MOST NORTHERN AREAS...WITH SOME BELOW ZERO READINGS
ACROSS THE ADIRONDACKS.
THE EUROPEAN MODEL HAS BEEN MOST BULLISH WITH THE COLD...INDICATING
-30C AIR REACHING INTO THE CAPITAL REGION BY SATURDAY!
SATURDAY WILL BE A WINDY AND BITTERLY COLD DAY. ANY SNOW
SHOWERS SHOULD BE CONFINED TO THE HIGHER TERRAIN WEST OF THE HUDSON VALLEY.
OTHERWISE IT WILL BE PARTLY SUNNY WITH TEMPERATURES NOT RISING MUCH
(IF AT ALL) ACROSS THE REGION. HIGHS WILL RANGE AROUND ZERO ACROSS
THE ADIRONDACK PARK...SINGLE NUMBERS MOST OTHER
ELEVATED AREAS...10-15 ALBANY SOUTHWARD.
THE WIND WILL LIKELY MAKE IT FEEL QUITE A BIT COLDER...WITH WIND CHILLS
BELOW ZERO EVERYWHERE...INTO THE POTENTIALLY DANGEROUS ZONE (LOWER THAN -30)
ACROSS MUCH OF OUR ELEVATED REGION.
SATURDAY NIGHT WILL BE CLEAR TO PARTLY CLOUDY AND EVEN COLDER. LOWS
WILL LOOK TO BE BELOW ZERO MOST EVERYWHERE...0 TO 10 BELOW
ALBANY SOUTHWARD...10 TO 20 BELOW NORTH AND WEST OF THE CAPITAL REGION.
THE WIND WILL ABATE SOME...BUT STRONG ENOUGH OF A BREEZE TO PRODUCE
DANGEROUS WIND CHILLS ACROSS MOST AREAS.
SUNDAY WILL BE MOSTLY SUNNY...LESS BREEZY BUT STILL VERY COLD. HIGH TEMPERATURES
WILL BE SIMILAR TO SATURDAY.
AS ARCTIC HIGH PRESSURE MOVES EAST ON SUNDAY NIGHT...A SOUTHERLY FLOW
WILL ALLOW THE FRIGID AIR MASS TO BEGIN TO MODERATE SUNDAY NIGHT AND ESPECIALLY
MONDAY. MOISTURE WILL INCREASE AS WELL WHICH COULD LEAD TO SOME SNOW SHOWERS
BY LATE MONDAY.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
WITH THE SLOW MOVING UPPER LEVEL TROUGH TO THE WEST OF THE
REGION...SOME ADDITIONAL LIGHT SNOW SHOWERS/FLURRIES WILL BE
POSSIBLE THROUGH THE REMAINDER OF THE OVERNIGHT HOURS AND INTO THE
DAY ON WEDNESDAY. LIMITED MOISTURE IN PLACE WILL KEEP THESE RATHER
SCATTERED IN COVERAGE...BRIEF IN DURATION...AND LIGHT IN
INTENSITY.
BASED ON THE CURRENT RADAR TRENDS AND 3KM HRRR GUIDANCE...WILL
INCLUDE TEMPO FOR MVFR CIGS/VSBYS DUE TO SNOW SHOWERS FOR THE
REMAINDER OF THE OVERNIGHT HOURS FOR ALL TAF SITES. WILL NOT
INCLUDE ANY IFR AT THIS TIME DUE TO LIMITED COVERAGE OF SNOW
SHOWER ACTIVITY...BUT CAN/T TOTALLY RULE IT OUT FOR KALB OR KPSF.
LIGHT OR CALM WINDS ARE EXPECTED FOR ALL SITES.
DURING THE DAY ON WEDNESDAY...FLYING CONDITIONS LOOK MAINLY
VFR WITH BKN-OVC CIGS AT 3500-4000 FT...ALTHOUGH SOME PERIODS OF
MVFR DUE TO SOMEWHAT LOWER CIGS OR PASSING SNOW SHOWERS CANNOT BE
RULED OUT. S-SW WINDS WILL BECOME WESTERLY AT 5-10 KTS BY THE MID
TO LATE MORNING HOURS. SKIES WILL START TO CLEAR OUT SOMEWHAT FOR
WEDNESDAY NIGHT...ALTHOUGH DEVELOPING LAKE EFFECT SNOW SHOWERS
WEST OF THE REGION WILL CONTINUE TO KEEP SCT-BKN CLOUDS AROUND.
OUTLOOK...
WEDNESDAY NIGHT THROUGH THURSDAY: MODERATE OPERATIONAL IMPACT.
SCATTERED -SHSN. BREEZY.
THURSDAY NIGHT TO FRIDAY: LOW OPERATIONAL IMPACT. ISOLATED -SHSN.
BREEZY.
FRIDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
SATURDAY THROUGH SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
TIDAL ISSUES ALONG THE ATLANTIC SEABOARD ARE RESULTING IN HIGHER
THAN NORMAL TIDES UP THE HUDSON RIVER. IT APPEARS POUGHKEEPSIE
WILL EXPERIENCE TIDAL IMPACTS WHICH MAY PERSIST THE NEXT COUPLE OF
DAYS. OTHERWISE...NO OTHER HYDROLOGICAL ISSUES ARE EXPECTED AT
THIS TIME.
WITH AN APPROACHING UPPER LEVEL TROUGH...SOME SNOW SHOWERS AND
FLURRIES ARE POSSIBLE THROUGH THURSDAY. TOTAL LIQUID EQUIVALENT
WILL BE VERY LIGHT...GENERALLY LESS THAN A TENTH OF AN INCH AT ANY
ONE LOCATION...PERHAPS A BIT HIGHER ACROSS THE WESTERN
ADIRONDACKS.
WITH COLDER TEMPERATURES ARRIVING BY LATER IN THE WEEK AND THE
UPCOMING WEEKEND...ICE COVER ON RIVERS AND LAKES WILL INCREASE IN
COVERAGE AND THICKNESS. TEMPERATURES SHOULD BE REMAIN COMPLETELY
BELOW FREEZING FROM WED NIGHT THROUGH THE REST OF 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.
&&
.CLIMATE...
BITTERLY COLD OVER THE WEEKEND WITH BELOW ZERO LOWS EXPECTED
SATURDAY NIGHT INTO SUNDAY MORNING ACROSS EAST CENTRAL NY AND
WESTERN NEW ENGLAND.
THE LAST TIME TEMPERATURES WERE BELOW ZERO WAS:
ALBANY NY: -9 DEGREES ON FEBRUARY 24, 2015
NOTE: THE LOW ON MARCH 6, 2015 WAS ZERO DEGREES
GLENS FALLS NY: -15 DEGREES ON MARCH 6, 2015
POUGHKEEPSIE NY: -2 DEGREES ON MARCH 6, 2015
BENNINGTON VT: -11 DEGREES ON MARCH 6, 2015
PITTSFIELD MA: -4 DEGREES ON MARCH 7, 2015
FEBRUARY 13TH...RECORD LOW MAXIMUM TEMPERATURES...
ALBANY: 8 DEGREES SET IN 1899
GLENS FALLS: 4 DEGREES SET IN 1979
POUGHKEEPSIE: 13 DEGREES SET IN 1979
FEBRUARY 14TH...RECORD LOWS...
ALBANY: -10 DEGREES SET IN 1987
GLENS FALLS: -24 DEGREES SET IN 2003
POUGHKEEPSIE: -14 DEGREES SET IN 1979
FEBRUARY 14TH...RECORD LOW MAXIMUM TEMPERATURES...
ALBANY: 4 DEGREES SET IN 1916
GLENS FALLS: 4 DEGREES SET IN 1987
POUGHKEEPSIE: 15 DEGREES SET IN 1979
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...LAKE EFFECT SNOW ADVISORY FROM NOON TODAY TO 6 PM EST THURSDAY
FOR NYZ032-033-038.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS/HWJIV/KL
NEAR TERM...HWJIV/KL/11
SHORT TERM...KL
LONG TERM...HWJIV
AVIATION...FRUGIS
HYDROLOGY...FRUGIS/KL
CLIMATE...IAA
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1228 AM EST WED FEB 10 2016
.SYNOPSIS...
LOW PRESSURE OFF THE MID-ATLANTIC COAST PASSES WELL SOUTH AND
EAST OF LONG ISLAND LATE TONIGHT THROUGH WEDNESDAY...THEN LIFTS
SLOWLY NORTHWEST ACROSS THE CANADIAN MARITIMES THROUGH THE END OF
THE WEEK. A STRONG COLD FRONT MOVES ACROSS THE WATERS LATE FRIDAY
NIGHT...FOLLOWED BY ARCTIC HIGH PRESSURE FOR THE WEEKEND. A
FRONTAL SYSTEM THEN APPROACHES EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
THE WINTER WEATHER ADVISORY HAS BEEN CANCELLED WITH THIS UPDATE.
THE NEW 00Z NAM CONTINUES THE TREND OF VERY LITTLE IN THE WAY OF
SNOWFALL OVERNIGHT INTO WEDNESDAY MORNING. ALL HIGH RES
GUIDANCE...INCLUDE THE HIRES NAM...HRRR...EXPERIMENTAL
HRRR...AND RAP ARE ONLY INDICATING SOME LIGHT SNOW THROUGH EARLY
WEDNESDAY MORNING. THE LAST SEVERAL RUNS OF THE SREF INDICATE A
MEAN SNOWFALL BETWEEN A HALF INCH AND AN INCH ACROSS THE AREA.
LATEST RADAR AND OBSERVATIONAL TRENDS ALSO SUPPORT THE
CANCELLATION OF THE ADVISORY. RADAR RETURNS HAVE GENERALLY
WEAKENED OVER THE LAST FEW HOURS JUST SOME FLURRIES BEING
REPORTED.
HAVE LOWERED SNOW AMOUNTS TO GENERALLY LESS THAN AN INCH INLAND TO
1 TO 2 INCHES NEAR THE COAST...ALTHOUGH IT COULD END UP BEING
CLOSER TO AN INCH THERE. THE LATEST SNOWFALL FORECAST MAY STILL BE
ON THE HIGH SIDE WITH THE POSSIBILITY MUCH OF THE AREA ONLY A
RECEIVES COATING TO LESS THAN AN INCH.
THE LOCAL AREA IS SANDWICHED BETWEEN TWO LOW PRESSURE
SYSTEMS...ONE ACROSS UPSTATE NEW YORK AND ONE ABOUT 175 MILES
SOUTH OF THE LONG ISLAND. A MESO HIGH IS LOCATED OVER NEW
ENGLAND...WHICH IS HELPING TO PROMOTE SUBSIDENCE AND PREVENT ANY
SIGNIFICANT LIFT FOR GOOD SNOW GROWTH. THERE WILL ALSO BE A
RELATIVE MINIMUM IN VORTICITY ADVECTION AS A STRONG PIECE OF
ENERGY MOVES OFFSHORE AT H5...AND ANOTHER APPROACHES FROM THE
MIDDLE ATLANTIC OVERNIGHT. THINKING IS THIS H5 SHORTWAVE
APPROACHING AND THE ENERGY ASSOCIATED WITH IT COULD HELP TO
GENERATE SOME LIGHT SNOW LATE TONIGHT INTO EARLY WEDNESDAY AS IT
NEARS THE AREA.
LOWS TONIGHT WILL RANGE FROM THE LOW 20S INLAND TO THE MID AND
UPPER 20S NEAR THE COAST.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/...
LOW PRES CONTINUES TO DEPART ON WEDNESDAY...AND ANY LIGHT SNOW
WILL TAPER OFF FROM WEST TO EAST IN THE MORNING. DRY CONDS
EXPECTED BY THE AFTERNOON THROUGHOUT. ANOTHER LOW DEVELOPS OFF THE
MID- ATLANTIC COAST WEDNESDAY NIGHT. FOR NOW...WILL ONLY CARRY
SLIGHT CHANCE POPS AS THE BULK OF THE PRECIP WILL STAY SOUTH OF
THE REGION.
HIGHS ON WEDNESDAY COULD REACH 40 IN MOST AREAS. LOWS WEDNESDAY
NIGHT WILL DROP INTO THE 20S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
MEAN UPPER TROF REMAINS ACROSS EASTERN NORTH AMERICA THIS PERIOD
WITH A HIGH AMPLITUDE RIDGE EXTENDING NORTHWARD ALONG THE WEST
COAST. THIS WILL RESULT IN AN ANOMALOUSLY COLD AIRMASS PLUNGING
SOUTH FROM THE ARCTIC AND INTO THE TRI-STATE AREA THIS WEEKEND. IN
FACT...HEIGHT AND TEMP FIELD ANOMALIES ARE ON THE ORDER OF 3-5 SD
BELOW NORMAL FOR THIS TIME PERIOD WITH 85H TEMPS SAT AND SAT NIGHT
-25 TO -30 DEG C. THIS WILL EQUATE TO DAYTIME HIGHS ON SAT
STRUGGLING TO GET TO 20 AND NOT OUT OF THE TEENS ON SUN.
OVERNIGHT LOWS SUN MORNING WILL BE NEAR OR BELOW ZERO WITH WIND
CHILLS MEETING ADVISORY CRITERIA...-15 TO -24 DEG F.
LOW PRESSURE OVER THE NORTH ATLANTIC AT THE ONSET OF THE PERIOD
WILL BE SLOW TO LIFT NE ACROSS THE CANADIAN MARITIMES...WHILE WEAK
HIGH PRESSURE SLIDES INTO THE AREA THU NIGHT INTO FRI MORNING. AN
ARCTIC COLD FRONT OVER THE EASTERN GREAT LAKES ON FRI PASSES
THROUGH LATE FRI NIGHT WITH THE COLDEST AIRMASS OF THE SEASON AND
IN FACT MANY YEARS FOR SOME LOCATIONS. A STRONG NW FLOW WILL BE
PRESENT ON THU BEHIND DEPARTING LOW PRESSURE AND AGAIN SAT AND SUN
BEHIND THE ARCTIC COLD FRONT. IN FACT...WINDS ON THESE DAYS WILL
LIKELY GUSTS UP TO 30 MPH. THUS...THIS WILL PRODUCE DANGEROUSLY
COLD WIND CHILLS SAT INTO SUN.
AS FOR ANY PCPN...THERE IS A LOW CHANCE LATE FRI NIGHT INTO SAT
MORNING OF A SNOW SQUALL ASSOC WITH THE ARCTIC COLD FRONT.
THEREAFTER...A FRONTAL SYSTEM APPROACHES MON INTO TUE WITH
SIGNIFICANT TIMING ISSUES AMONGST THE GLOBAL MODELS. AIRMASS
MODERATES SIGNIFICANTLY MON INTO TUE WITH HIGH IN 30S MON AND INTO
THE 40S ON TUE. THIS WOULD LIKELY BE A SNOW TO RAIN EVENT...BUT
THERE IS STILL MUCH UNCERTAINTY AT THIS TIME PERIOD.
&&
.AVIATION /05Z WEDNESDAY THROUGH SUNDAY/...
A TROUGH OF LOW PRESSURE IN THE VICINITY WILL MOVE THROUGH THE
REGION OVERNIGHT...MOVING NORTH OF THE AREA WEDNESDAY MORNING. LOW
PRESSURE REMAINS NORTHEAST OF THE AREA INTO WEDNESDAY NIGHT.
MAINLY VFR VISIBILITIES IN LIGHT SNOW WITH MVFR CEILINGS THROUGH
MOST OF THE NIGHT. THERE WILL BE TIMES IN SLIGHTLY HEAVIER SNOW THAT
VISIBILITIES BECOME IFR WITH MVFR TO IFR CEILINGS. LOW FORECAST
CONFIDENCE WITH FORECAST UNCERTAINTY. AS THE SNOW ENDS EARLY
WEDNESDAY MORNING CONDITIONS IMPROVE BACK TO VFR.
TOTAL SNOW ACCUMULATIONS AROUND 1 INCH IS POSSIBLE.
WINDS LIGHT AND VARIABLE OVERNIGHT WILL BECOME WESTERLY 5 TO 10 KT
WEDNESDAY MORNING WITH GUSTS DEVELOPING AROUND MIDDAY. AT THE NYC
METRO TERMINALS GUSTS CONTINUE THROUGH THE WEDNESDAY NIGHT WHILE
GUSTS SUBSIDE AT THE REMAINDER OF THE TERMINALS.
.OUTLOOK FOR 06Z THU THROUGH SUN...
.LATE WED NIGHT...VFR. W GUSTS 20-25KT AT THE NYC METRO TERMINALS.
.THU...SLIGHT CHC -SHSN...OTHERWISE VFR. WNW GUSTS 25-30KT.
.FRI...VFR.
.SAT-SUN...VFR. NW GUSTS 20-30KT.
&&
.MARINE...
FORECAST ON THE WATERS REMAINS ON TRACK.
SCA CONDS PERSIST ON THE OCEAN WATERS...MAINLY FOR HIGH SEAS
TONIGHT. THE PRES GRADIENT TIGHTENS ON WEDNESDAY...AND WIND GUSTS
OF 25-30 KT WILL DEVELOP ON ALL WATERS LATE IN THE MORNING. WILL
HOIST SCA FOR THE SOUND/HARBOR/BAYS FOR WEDNESDAY AFTERNOON AND
NIGHT. FOR THE OCEAN...GALES POSSIBLE WEDNESDAY NIGHT. WILL GO
AHEAD AND ISSUE A GALE WATCH FOR WEDNESDAY NIGHT.
GALE CONDITIONS MAY LINGER ON THE OCEAN WATERS INTO THU WITH A
STRONG NW GRADIENT ON THE BACKSIDE OF DEPARTING LOW PRESSURE.
THERE WILL BE A BRIEF LULL IN THE WINDS FRI INTO FRI NIGHT WITH
SEAS POSSIBLY LINGERING AROUND 5 FT ON THE OCEAN WATERS. NEAR GALE
FORCE WINDS RETURN SAT INTO SUN FOLLOWING THE PASSAGE OF AN
ARCTIC COLD FRONT LATE FRI NIGHT.
&&
.HYDROLOGY...
LITTLE IF ANY PRECIPITATION EXPECTED THU THROUGH SAT WIT SNOW
SHOWER ACTIVITY. A FRONTAL SYSTEM APPROACHES MON INTO TUE WITH THE
CHANCE OF A MORE SIGNIFICANT PCPN EVENT. THERE IS STILL MUCH
UNCERTAINTY WITH THE TIMING AND PTYPE AT THIS POINT IN TIME.
&&
.TIDES/COASTAL FLOODING...
A GRADUALLY DOWNWARD TREND IN SURGE AND ASTRONOMICAL TIDES EXPECTED
OVER THE NEXT COUPLE OF DAYS.
GENERALLY LOOKING AT MINOR COASTAL FLOODING CONCERNS FOR NY
HARBOR...COASTAL NE NJ AND WESTERN LI SOUND WITH THIS EVENINGS HIGH
TIDE CYCLE...AND LOCALLY MODERATE ALONG THE SOUTH SHORE BACK BAYS OF
LONG ISLAND. SURGE LOWERS FURTHER FOR WEDNESDAY MORNINGS HIGH TIDE
CYCLE...WITH MINOR COASTAL FLOODING FOR THE MOST VULNERABLE LOCALES
OF THE SOUTH SHORE BAYS...NY HARBOR...NE NJ...AND WESTERN LI SOUND.
ASTRONOMICAL TIDES WILL CONTINUE TO LOWER FOR WEDNESDAY NIGHTS HIGH
TIDE...WITH ANY BRIEF LOCALIZED MINOR IMPACTS LIKELY BEING RELEGATED
TO THE SOUTH SHORE BAYS OF LI.
SURF WILL CONTINUE TO LOWER SO BEACH IMPACTS ARE NO LONGER
EXPECTED.
&&
.CLIMATE...
WITH THE EXTREMELY COLD AIRMASS FORECAST SATURDAY INTO
SUNDAY...RECORD MINIMUMS AND RECORD LOW MAXIMUMS MAY BE REACHED.
HERE ARE THE RECORDS:
STATION.........RECORD MINIMUM.............RECORD LOW MAXIMUM
FOR 2/14 FOR 2/14
NYC.................2 (1916)....................17 (1979)....
LGA.................1 (1979)....................15 (1979)....
JFK.................4 (1979)....................17 (1979)....
ISP.................7 (2015)....................26 (1987)....
EWR.................0 (1979)....................15 (1979)....
BDR.................3 (2015*)...................18 (1979)....
*IN 1979 AS WELL
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...COASTAL FLOOD ADVISORY UNTIL 2 AM EST EARLY THIS MORNING FOR
CTZ009.
COASTAL FLOOD ADVISORY FROM 11 AM THIS MORNING TO 3 PM EST
THIS AFTERNOON FOR CTZ009.
NY...COASTAL FLOOD ADVISORY UNTIL 2 AM EST EARLY THIS MORNING FOR
NYZ071-078-081-177.
COASTAL FLOOD ADVISORY FROM 11 AM THIS MORNING TO 3 PM EST
THIS AFTERNOON FOR NYZ071-078-177.
COASTAL FLOOD ADVISORY FROM 7 AM THIS MORNING TO NOON EST
TODAY FOR NYZ074-075-080-178-179.
NJ...COASTAL FLOOD ADVISORY FROM 7 AM THIS MORNING TO NOON EST
TODAY FOR NJZ006-106-108.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 6 AM EST
THURSDAY FOR ANZ330-335-338-340-345.
GALE WATCH FROM THIS EVENING THROUGH LATE TONIGHT FOR ANZ350-
353-355.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ350-
353-355.
&&
$$
SYNOPSIS...MPS/DW
NEAR TERM...MPS/DS
SHORT TERM...MPS
LONG TERM...DW
AVIATION...BC/MET
MARINE...MPS/DS/DW
HYDROLOGY...MPS/DW
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
807 AM EST WED FEB 10 2016
.SYNOPSIS...
LOW PRESSURE ACROSS NEW ENGLAND WILL CONTINUE TO MOVE NORTHEAST AWAY
FROM THE REGION TODAY. HIGH PRESSURE WILL BUILD EASTWARD INTO THE
REGION THURSDAY AND THEN MOVE THROUGH ON FRIDAY BEFORE GIVING WAY TO
A ARCTIC COLD FRONTAL BOUNDARY BY THE END OF THE WEEK. ON SUNDAY,
ANOTHER AREA OF HIGH PRESSURE WILL BUILD SOUTHWARD INTO THE REGION
AS LOW PRESSURE FORMS ACROSS THE SOUTHERN UNITED STATES BY MONDAY.
THIS AREA OF LOW PRESSURE WILL THEN TRACK UP THE EAST COAST ON
TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
755 AM: NO STORM TOTAL SNOW MAP THIS MORNING. TOO FAST A DEPARTURE.
SNOW PROBS CONTINUE AS POSTED EARLY THIS MORNING. HOWEVER..COUNT
ON SCATTERED .1 TO .5 INCH IN NJ/DE 8A-10A. NO OTHER CHANGES AT
THIS TIME. SPS/HWO UPDATED. NO NOW CASTS...COVERED BY SPS.
6 AM UPDATE...NO MAJOR CHANGES TO THE FORECAST. HIGH RESOLUTION
MODELS SHOW THE CURRENT BAND OF SNOW SHOWERS MOVING THROUGH OUR
AREA SHOULD DISSIPATE OR MOVE OFF THE COAST BY 10 AM.
PREVIOUS NEAR TERM DISCUSSION...
UPPER LEVEL SHORT WAVE TROUGH LIFTS THROUGH THE REGION EARLY IN THE
DAY. AS A RESULT, WE SHOULD SEE LINGERING SNOW SHOWERS MOVE OUT OF
THE REGION BY MID DAY.
IN THE LOW LEVELS, NORTHWESTERLY FLOW DEVELOPS, RESULTING IN LOW
LEVEL COLD AIR ADVECTION. AS SUCH, EXPECT HIGHS WILL ONLY BE IN THE
30S FOR MOST OF THE REGION, WHILE THE POCONOS MAY NOT GET OUT OF THE
20S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
A SECOND, LESS DEFINED, MID AND UPPER LEVEL SHORT WAVE TROUGH WILL
APPROACH FROM THE WEST OVERNIGHT. CONTINUED THE TREND OF A SMALL
CHANCE OF SNOW SHOWERS. HOWEVER, I AM NOT EXPECTING MUCH IN THE WAY
OF ACCUMULATING SNOW FOR TWO REASONS. FIRST, THE REGION WILL
GENERALLY BE UNDER THE LEFT REAR QUADRANT OF AN UPPER LEVEL JET
THROUGH THIS TIME, WHICH SHOULD LIMIT LIFT. SECONDLY, IN ADDITION TO
THE COLD AIR ADVECTION, ALSO EXPECT CONSIDERABLE DRY AIR ADVECTION
IN THE BOUNDARY LAYER (SINGLE DIGIT DEW POINTS ARE POSSIBLE BY EARLY
THURSDAY MORNING), SO MOISTURE WILL BE LIMITED AS WELL. WE WILL BE
LOOKING FOR A LAKE EFFECT SNOW BAND FROM LERIE TO POSSIBLY STREAM
ACROSS THE APPALACHIANS INTO A PORTION OF E PA AND NJ.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
THE EXTENDED WILL LIKELY FEATURE BOTH THE PROSPECTS FOR THE COLDEST
AIR OF THE SEASON CENTERED ON SUNDAY MORNING AND A STRENGTHENING LOW
PRESSURE SYSTEM TRACKING UP THE EAST COAST EARLY NEXT WEEK.
THURSDAY AND THURSDAY NIGHT: HIGH PRESSURE WILL GRADUALLY BUILD
EASTWARD FROM THE OHIO VALLEY TOWARD THE REGION. OUR REGION WILL
CONTINUE TO SEE STRONG CAA WITH A WEST-NORTHWEST WIND OFF THE
EASTERN GREAT LAKES. BUFKIT ANALYSIS SHOWS THAT STRONG WIND GUSTS
MAY REACH 30 MPH AT TIMES. ALSO LOW LEVEL LAPSE RATES WILL ALSO
STEEPEN DURING THE DAY WHICH COULD BE ENOUGH TO DEVELOP SOME
SCATTERED SNOW SHOWERS AND FLURRIES DURING THE DAY WITH THE
HIGHEST COVERAGE AIDED BY ELEVATION ACROSS EASTERN PA AND NW NJ.
WITH THE STRONG CAA PUSH WILL TREND TEMPERATURES A BIT LOWER THAN
MET/MAV AND ENSEMBLE GUIDANCE.
THE PRESSURE GRADIENT WILL RELAX THURSDAY NIGHT ALLOWING FOR
WINDS TO DECREASE AS A HIGH PRESSURE SYSTEM MOVES INTO THE REGION.
CONDITIONS LOOK MORE FAVORABLE FOR RADIATIONAL COOLING COMPARED TO
TONIGHT.
FRIDAY AND SATURDAY: HIGH PRESSURE WILL MOVE THROUGH THE REGION ON
FRIDAY. THIS HIGH PRESSURE SYSTEM WILL GIVE WAY TO ANOTHER ARCTIC
COLD FRONT. THE FRONT MOVES THROUGH THE REGION FRIDAY NIGHT AND
SATURDAY. TRENDS WITH BOTH THE OPERATIONAL AND ENSEMBLE GUIDANCE
FORM A COASTAL LOW PRESSURE SYSTEM SOUTHEAST OF US AND OFFSHORE,
SO THE POSSIBILITY OF A COASTAL LOW NEAR US IN THIS PERIOD HAS
GREATLY DECREASED. IT WILL BE A VERY COLD AND WINDY PERIOD WITH
ANOTHER ROUND OF NW FLOW SNOW SHOWERS AND FLURRIES BEHIND THE
FRONT WITH THE HIGHEST COVERAGE IN THE HIGH TERRAIN AREAS IN
EASTERN PA AND NW NJ, SIMILAR TO THE MIDDLE OF THIS WEEK. BUFKIT
ANALYSIS SHOWS THE POTENTIAL FOR MIXING AGAIN SATURDAY SIMILAR TO
THURSDAY SO WIND GUSTS COULD BE QUITE STRONG, OVER 30 MPH AGAIN.
SATURDAY NIGHT THROUGH SUNDAY NIGHT: ANOTHER POTENT AREA OF ARCTIC
HIGH PRESSURE WILL BUILD INTO THE REGION WITH THE COLDEST SHOT OF
AIR OF THE SEASON SO FAR. 850 MB LOOK TO DIVE BELOW -25C ACROSS MOST
OF REGION AS CURRENTLY MODELED. AS IN OTHER PERIODS WILL CONTINUE TO
NUDGE TEMPERATURES A COUPLE OF DEGREES COOLER THAN MOST ENSEMBLE
GUIDANCE. NORTHWEST WINDS ALTHOUGH NOT AS STRONG AS SATURDAY WILL
LIKELY TO BELOW ZERO WIND CHILLS, PUSHING ADVISORY CRITERIA IN
SPOTS FROM -10 IN THE DELMARVA TO LOWER THAN -20 IN THE POCONOS.
PRESIDENTS DAY THROUGH TUESDAY: HIGH PRESSURE WILL GRADUALLY MOVE
EAST OF THE REGION AND WILL GIVE WAY TO A STORM SYSTEM THAT IS
CURRENTLY MODELED TO FORM ACROSS THE SOUTHERN UNITED STATES MONDAY
AND TRACK UP THE EAST COAST TUESDAY. TWO CAMPS ARE CURRENTLY
PRESENT WITH THE TRACK OF THE STORM SYSTEM. THE MAIN DIFFERENCES
BETWEEN THE TWO SOLUTIONS ARE THE SPEED OF VARIOUS SHORTWAVES
WHICH ULTIMATELY DEVELOP THE STORM ACROSS THE SOUTHERN UNITED
STATES AND THE DEGREE OF MID-LEVEL RIDGING MODELS DEVELOP AHEAD OF
IT. THE UKMET AND ECMWF ARE SLOWER WITH OVERALL TIMING ALLOWING
FOR MID-LEVEL RIDGING TO FORM OVER THE REGION AND IN NEW ENGLAND.
THIS ALLOWS FOR AS WARMER AND FURTHER WEST TRACK WHICH WOULD
RESULT IN MAINLY A RAIN EVENT. THE FASTER GFS AND CMC SOLUTIONS
SHIFT THE DEVELOPING SYSTEM FURTHER EAST AND ARE FASTER, TRACKING
IT UP THE EAST COAST WHICH WOULD BE A SNOWIER OUTCOME. FOR NOW
WILL TAKE A MIDDLE OF THE ROAD APPROACH, THIS BRINGS SNOW IN
MONDAY WHICH GRADUALLY MIXES AND CHANGES TO RAIN BY TUESDAY.
ENSEMBLE DATA IS CURRENTLY LEANING TOWARD THE WARMER WESTWARD
TRACK. HOWEVER, GIVEN THIS IS SEVERAL DAYS A LOT OF ENSEMBLE
SPREAD IS STILL PRESENT AND THE VARIOUS FEATURES INVOLVED WILL NOT
EVEN SAMPLED BY OBSERVATIONAL DATA FOR SEVERAL MORE DAYS.
&&
.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
EARLY TODAY....IFR SNOW SHOWERS WILL END FROM W TO E ACROSS NJ/DE
BY 15Z, PER THE HRRR HOURLY UPDATES AND TRENDS. MVFR FLURRIES IN E
PA AND MARYLAND E SHORE WILL BECOME ISOLATED BY 15Z AS DRIER AIR
ARRIVES ON GUSTY WESTERLY WINDS.
AFTER 15Z TODAY...VFR SCT-BKN AOA 4000 FT. WEST WIND GUST 20-25
KT.
TONIGHT...VFR CIGS MAY LOWER TO MVFR CONDS IN SNOW SHOWERS LATE.
WEST WIND GUSTS TO 20 KT.
OUTLOOK...
THURSDAY: MAINLY VFR, SOME BRIEF MVFR RESTRICTIONS IN ISOLATED
SNOW SHOWERS AND FLURRIES. NORTHWEST WINDS 15-25 KNOTS WITH HIGHER
GUSTS.
THURSDAY NIGHT AND FRIDAY: VFR. NORTHWEST WINDS UNDER 15 KNOTS SHIFTING
TO SOUTHWEST ON FRIDAY
FRIDAY NIGHT AND SATURDAY: MAINLY VFR, POSSIBLE MVFR RESTRICTIONS
IN SCATTERED SNOW SHOWERS. NORTHWEST WINDS INCREASING SATURDAY
FROM 15-25 KNOTS WITH HIGHER GUSTS ON SATURDAY.
SUNDAY...VFR WITH DIMINISHING NORTHWEST WINDS.
&&
.MARINE...
SCA CONDITIONS FOR WINDS WILL CONTINUE ON THE COASTAL WATERS AND THE
DELAWARE BAY TODAY. SEAS HAVE BEEN STEADILY DECREASING OVERNIGHT,
AND MAY DROP BELOW 5 FT FOR MUCH OF THE DAY.
TONIGHT...HAVE EXTENDED THE SCA THROUGH THE OVERNIGHT HOURS AND
DELAYED THE START TIME OF THE GALE WATCH. MODEL SOUNDINGS FROM NAM,
RAP, AND GFS AND THE PROBABILISTIC WIND SPEED GUIDANCE OF THE NAEFS
AND GEFS SHOW A MINIMAL CHANCE FOR GALES OVERNIGHT. IN ORDER TO GET
GALE FORCE WINDS, THERE WOULD HAVE TO BE A VERY DEEP MIXING LAYER
WHICH SEEMS UNLIKELY GIVEN THE PERSISTENT MID LEVEL CLOUD COVER.
LIGHT FREEZING SPRAY WILL BE POSSIBLE ON THE BAY AND NEAR COASTAL
WATERS OVERNIGHT.
MAY ISSUE GLW AT 915 AM FOR DE BAY BEGINNING 4 AM THURSDAY FOR
WNW FLOW FUNNELING.
OUTLOOK...
MAY CONVERT GLA TO GLW ALL WATERS AT 915 AM.
FOR NOW THE GALE WATCH HAS BEEN EXTENDED INTO THURSDAY EVENING.
FAIRLY HIGH CONFIDENCE IS PRESENT FOR NORTHWEST WIND GUSTS NEAR
AND JUST OVER GALE FORCE THROUGHOUT MUCH OF THURSDAY AND INTO THE
EARLY EVENING. SEAS WILL ALSO BE AROUND FIVE FEET BEFORE
DECREASING LATER THURSDAY NIGHT. SCA NORTHWEST WINDS WILL CONTINUE
INTO EARLY FRIDAY. AFTER A LULL WITH SEAS AND WINDS FOR A GOOD
PART OF FRIDAY AND MAYBE INTO EARLY SATURDAY AN ARCTIC COLD FRONT
WILL LEAD TO RAMP UP ON SATURDAY. ANOTHER ROUND OF NORTHWEST GALE
FORCE GUSTS ARE LIKELY SATURDAY AFTERNOON AND EVENING WITH SEAS
NEAR AND OVER FIVE FEET. STRONG NORTHWEST WIND GUSTS BELOW GALE
FORCE WILL LINGER INTO SUNDAY. IN ADDITION TO THE THREAT FOR GALES
SEVERAL ROUNDS OF FREEZING SPRAY CONDITIONS ARE POSSIBLE AS WELL
WITH THE FIRST ROUND WEDNESDAY NIGHT INTO THURSDAY AND THE
POTENTIAL FOR MODERATE TO HEAVY FREEZING SPRAY THIS WEEKEND.
&&
.TIDES/COASTAL FLOODING...
WITH A SHIFT TO OFF SHORE FLOW, AND LOWER ASTRONOMICAL TIDES, COASTAL
FLOODING CONCERNS ARE WINDING DOWN, WITH TWO EXCEPTIONS.
FIRST, FOR THE NORTHERN NEW JERSEY SHORE, WINDS WERE SLOWER TO SHIFT
TO WESTERLY AS COMPARED TO THE REST OF THE REGION. AS A RESULT,
WATER LEVELS AT SANDY HOOK AS WE APPROACH LOW TIDE ARE RUNNING
SLIGHTLY HIGHER THAN GUIDANCE. THUS, COULD SEE ONE MORE HIGH TIDE
CYCLE WITH MINOR COASTAL FLOODING THIS MORNING.
FOR CAROLINE, TALBOT, AND QUEEN ANNE`S COUNTY IN MD, EXPECT MINOR
COASTAL FLOODING WITH THE HIGH TIDE CYCLE THAT WILL OCCUR BY 9 AM
THIS MORNING.
&&
.CLIMATE...
NEAR RECORD COLD IS EXPECTED FOR PORTIONS OF OUR AREA SUNDAY
MORNING AND BY FAR THE COLDEST AIR OF THE SEASON SO FAR.
AM ANTICIPATING TEMPS THROUGHOUT OUR FORECAST AREA WITH 3F OF ZERO
(WIND IS THE EQUALIZER) ANYTIME FROM MIDNIGHT THROUGH 8 AM SUNDAY
EXCEPT COLDER KMPO. THIS HAS BEEN ADVERTISED BY THE GFS/ECMWF 2M
TEMPS CYCLICALLY FOR THE PAST 3 DAYS. THEREFORE, BEST CHANCE FOR
RECORD EQUALING OR EXCEEDING FOR VALENTINES DAY THE 14TH WOULD BE
KABE, KTTN AND KPHL.
SNOW COVER MAY HELP A BIT I-95 NORTHWESTWARD...AND WE`LL SEE WHERE
WE ARE AT BY THURSDAY EVENING. NEW DUSTINGS APPEAR ON THE WAY THE
NEXT 30 HOURS.
BE A GOOD IDEA TO CHECK ON ELDERLY/PETS DURING THE WEEKEND AND CHECK
FUEL SUPPLIES IN ADVANCE...BY FRIDAY. AVOID GOING WITHOUT HEAT
THIS WEEKEND. WONT TAKE LONG FOR WIND DRIVEN COLD TO FREEZE WATER
PIPES IN UNHEATED FACILITIES.
2015-16 SO FAR RER 14TH
ABE 8......... -1 1979
ACY 10........ -6 1979
PHL 12........ +2 1979
ILG 12........ -4 1979
RDG 10........ -4-1983
TTN 9......... 0 1916
GED 13........ -7 1979
MPO -1........ -12 1970
SO, THIS WILL BE WIND DRIVEN COLD WITH MANY AREAS EXPERIENCING
WIND CHILL VALUES OF 15 TO 20 BELOW ZERO...POSSIBLY 25 BELOW IN
THE HILLS AND MOUNTAINS OF NORTHWEST NEW JERSEY AND NORTHEAST
PENNSYLVANIA.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...COASTAL FLOOD ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
NJZ012>014-020-026.
DE...NONE.
MD...COASTAL FLOOD ADVISORY UNTIL 9 AM EST THIS MORNING FOR MDZ015-
019-020.
MARINE...GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
ANZ430-431-450>455.
SMALL CRAFT ADVISORY UNTIL 6 AM EST THURSDAY FOR ANZ430-431-
450>455.
&&
$$
SYNOPSIS...GAINES
NEAR TERM...DRAG/JOHNSON 808
SHORT TERM...JOHNSON 808
LONG TERM...GAINES
AVIATION...DRAG/GAINES/JOHNSON 808
MARINE...DRAG/GAINES/JOHNSON 808
TIDES/COASTAL FLOODING...
CLIMATE...808
AREA FORECAST DISCUSSION...CORRECTED WWA SECTION
NWS MELBOURNE FL
430 AM EST WED FEB 10 2016
.DISCUSSION...
CURRENT...
LARGE DEEP LAYER LOW CONTINUES TO COVER THE BREADTH OF THE ERN CONUS
WITH COLD HIGH PRES AT THE SFC BUILDING EWD FROM THE CTRL CONUS INTO
THE ERN CONUS/FL. THE STRONG/GUSTY W-NW FLOW OF TUE HAS EASED SOME
OVER LAND SINCE SUNSET...BUT STILL REMAINS BREEZY IN A FEW LOCATIONS
OVER THE CTRL CWA NEAR THE COAST. A LARGE SWATH OF CI/CS OVHD HAS
BEEN SLOWLY SHIFTING S/E...BUT CONTINUES ACROSS THE SRN HALF OF THE
CWA IN RR QUAD OF DEPARTING ST JETMAX IN EXCESS OF 150KT. THIS IS
HELPING TO KEEP TEMPS A BIT ABOVE THE CURRENT FCST FOR THE CENTRAL
AND ESPECIALLY THE SRN CWA. ALSO WINDS HAVE DROPPED OFF SOME WHERE
THE CURRENT ADVISORY FOR WIND CHILLS IS IN EFFECT... AND
CONSEQUENTLY WCI`S ARE AOA 40F THERE ATTM. WHILE THERE IS STILL TIME
FOR THESE VALUES TO REACH FCST OF U20S-L30S...WILL TAKE A CLOSE LOOK
AT ZFP ISSUANCE TIME TO SEE IF ANY ADJUSTMENTS NEED TO BE MADE.
TODAY/TONIGHT...
MODEL GUIDANCE REMAINS CONSISTENT IN SHOWING THE SRN LOBE OF THE
COLD HIGH SLIDING EAST ACROSS THE GOMEX AND OVER FL BY LATE TONIGHT.
H30-H20 RH PROGS INDICATE THAT THE HIGH CLOUDS WILL SHIFT S/E OF THE
SRN CWA LATER THIS MORNING...LEAVING SUNNY SKIES... BUT CONTINUE
COLD TEMPS IN ITS WAKE. MOS GUID CONTINUES TO INDICATE U50S FOR THE
NRN HALF CWA AND AROUND 60F TO THE SOUTH. IT ALSO SHOWS BLYR WINDS
OF AROUND 17-18KT ACROSS THE NRN HALF CWA THIS AFTN WHICH IS RIGHT
AT THE CUSP FOR A LAKE WIND ADVISORY. GIVEN THAT MOS HAS BEEN
PERFORMING PRETTY WELL WITH WINDS THE LAST SEVERAL DAYS...WILL GO
AHEAD AND ISSUE NPW/LWA FROM OSCEOLA/BREVARD NWD FOR THIS AFTN.
WIDESPREAD MINS IN THE 30S TONIGHT AS SFC HIGH CRESTS OVER THE CWA
AROUND 12Z THU. SETUP CONTINUES TO LOOK PRETTY DECENT FOR FROST AND
A FEW POCKETS OF (NEAR) FREEZING TEMPS FOR THE INTERIOR. BEST CHANCE
REMAINS AROUND THE LAKE GEORGE/OCALA FOREST REGION...AND SUBSEQUENT
SHIFTS MAY NEED TO CONSIDER A FREEZING WARNING FOR THAT AREA BASED
ON 12Z MOS TEMP TRENDS. MAY ALSO NEED A FROST ADVISORY FOR A GOOD
CHUNK OF THE CWA FOR LATE TONIGHT.
THU-FRI...
QUIET WX PATTERN TO END THE WORK WEEK AS A WEAK HI PRES RIDGE OVER
THE SRN PLAINS IS PULLED INTO THE GOMEX BY THE DEPARTING JET STREAK
OVER THE SRN GOMEX/CENTRAL FL PENINSULA. STRONG SUBSIDENCE INVERSION
IN THE H90-H60 LYR WILL KEEP PWAT VALUES WELL BLO 1.0" WHILE
LIMITING VERTICAL MIXING TO LESS THAN 10KFT.
NWRLY WINDS ON THU WILL KEEP MAX TEMPS IN THE L/M60S...ABOUT 10F BLO
AVG. LIGHT WINDS THU NIGHT AS THE RIDGE AXIS EXPANDS OVER THE
CENTRAL PENINSULA...RESULTING IN GOOD RADIATIONAL COOLING.
HOWEVER...A SLIGHT W/SW COMPONENT WILL ALLOW MINS TO RECOVER INTO
THE L/M40S OVER MOST OF THE CWA...THOUGH POCKETS OF U30S PSBL IN
WIND PROTECTED AREAS N OF I-4 AS WELL AS THE KISSIMMEE PRAIRIE.
W/SWRLY FLOW TO CONT ON FRI AS THE RIDGE AXIS IS SHUNTED INTO S FL
BY A BROAD STORM SYSTEM FCST TO DVLP OUT OF THE NEXT SHORT WAVE BY
LATE WEEK...MAX/MIN TEMPS TO RECOVER TO WITHIN A DEG OR TWO OF CLIMO
AVGS...L/M70S AND U40S/L50S RESPECTIVELY.
SAT-TUE...
PROGRESSIVE WX PATTERN INTO EARLY NEXT WEEK AS A 140-160KT JET
STREAK OVER THE CENTRAL/WRN PAC PLOWS ITS WAY INTO THE ERN PAC/WRN
CONUS. TROFFING PATTERN OVER THE ERN CONUS EARLY SAT WILL EJECT NEWD
INTO THE NW ATLC OVER THE WEEKEND...FOLLOWED BY A SECOND TROF THAT
WILL FORM OVER THE UPR MIDWEST/GREAT LAKES REGION BY DAYBREAK MON AS
THE PAC JET PUSHES ITS THE ASCENDING LEFT EXIT QUAD ACRS THE CENTRAL
CONUS.
BACK DOOR FRONT WITH ATTENDANT NRLY WIND SURGE WILL PUSH INTO
CENTRAL FL ON SUN BUT WILL STALL AND WASH OUT LATE SUN NIGHT AS HI
PRES OVER THE ERN SEABOARD BUILDS OFFSHORE AND WINDS VEER TO THE
E/SE. WEAK CAA SAT/SUN AS WINDS VEER FROM N/NW TO NE...BUT LESS THAN
10F BLO AVG. DEEPENING ONSHORE FLOW WILL ERODE THE SUBSIDENCE
INVERSION THRU THE H100-H85 LYR AND MAY ALLOW A FEW COASTAL SHRAS TO
DVLP SHOWERS SUN AFTN/SUN NIGHT. SHRA CHCS INCRS AND MAY SPREAD
INLAND MONDAY AS WINDS VEER MORE TO E OR SE AHEAD OF THE NEXT COLD
FRONT. THE 10/00Z GFS/ECMWF RUNS CONT IN GENERAL AGREEMENT WITH A
FROPA EARLY NEXT WEEK...BUT ARE LEANING MORE TOWARD THIS OCCURRING
DURING THE DAY TUE.
&&
.AVIATION...
VFR. BKN-OVC250 KMLB-KSUA SHIFTS S/E THROUGH 12-14Z. SWATH OF
SHALLOW MARINE SC AIDED BY H50 VORT LOBE WILL PRODUCE FAST MOVING
DECK NEAR BKN050 AROUND ISM-MCO SWD THROUGH ROUGHLY THE SAME TIME
PERIOD...AND MAY EXTEND EWD TO MLB-SUA. OTRW...W-NW WINDS FROM ABOUT
280-290 WILL INCREASE TO 16-18KT/G23-25KT THIS AFTERNOON.
&&
.MARINE...
TODAY/TONIGHT...GLW WILL BE ALLOWED TO EXPIRE AT 09Z/4AM AND DON`T
ANTICIPATE ANY CHGS FORTHCOMING TO THE SCA FOR EITHER THE NEAR SHORE
OR OFFSHORE WATERS. EVEN AT SPEEDS OF 20-25KT...OFFSHORE COMPONENT
TO WINDS (WHICH HAVE BEEN RUNNING CLOSE TO 290 DEG) WILL CONTINUE TO
KEEP HIGHER SEAS WELL AWAY FROM THE COAST. DATA FROM BUOY 41009
SHOWS 7FT SEAS REMAIN CONFINED RIGHT AROUND AND BEYOND 20NM FROM
SHORE. THE SCA OUT TO 20NM WILL TRANSITION TO A CAUTIONARY STMT AT
15Z/10AM...WHILE THE SCA BEYOND 20NM WILL CONTINUE THROUGH 09Z/4AM
THU. SEAS 5-7FT NEAR SHORE AND 7-9FT OFFSHORE WILL GRADUALLY SUBSIDE
TO 4-5FT NEAR SHORE AND 6-7FT OFFSHORE BY TONIGHT.
THU-THU NIGHT...DIMINISHING WINDS THRU THE DAY AS A HI PRES RIDGE
OVER THE GOMEX NUDGES ITS WAY INTO THE FL PENINSULA/NRN BAHAMAS.
MODERATE TO FRESH N/NW BREEZE AT DAYBREAK BCMG GENTLE TO MODERATE BY
MIDDAY...THEN A LIGHT TO GENTLE NRLY BREEZE THRU SUNSET. POSITION
OF THE RIDGE AXIS JUST S OF THE I-4 CORRIDOR WOULD GENERATE VRBL
WINDS BLO 10KTS OVERNIGHT... W/SW FROM THE CAPE NWD...N/NE FROM THE
CAPE SWD. SEAS SUBSIDING FROM 4-6FT NEARSHORE AND 5-7FT OFFSHORE
EARLY IN THE DAY TO 2-4FT NEARSHORE AND 3-5FT OFFSHORE ARND
SUNSET...THEN 2-4FT AREAWIDE OVERNIGHT.
FRI-FRI NIGHT...BROAD STORM SYSTEM DVLPG OVER NEW ENGLAND AND OFF
THE MID ATLC COAST WILL SHUNT THE RIDGE AXIS INTO S FL/FL STRAITS.
RELATIVELY TIGHT PGRAD ON THE N FLANK OF THE RIDGE WILL GENERATE A
GENTLE TO MODERATE W/SW BREEZE FROM SEBASTIAN INLET NWD THRU THE
DAY...BCMG MODERATE TO FRESH WRLY BREEZE AFT SUNSET AND OVERNIGHT. S
OF SEBASTIAN INLET...PGRAD WILL BE RELATIVELY WEAK THRU THE DAY...
RESULTING INT A LIGHT WRLY BREEZE. HOWEVER...PGRAD WILL TIGHTEN
OVERNIGHT AS THE RIDGE AXIS MIGRATES INTO THE FL STRAITS...ALLOWING
THE MODERATE TO FRESH WRLY BREEZE TO EXPAND INTO THE SRN LEG BY
DAYBREAK. OFFSHORE BREEZE WILL LIMIT NEARSHORE SEAS TO 2-3FT...
OFFSHORE SEAS BUILDING FROM 2-3FT TO 3-4FT THRU THE DAY...THEN TO
4-5FT OVERNIGHT.
SAT-SAT NIGHT...DRY FRONTAL BOUNDARY WILL PUSH THRU THE LCL ATLC
WATERS...ALLOWING WINDS TO FRESHEN OUT OF THE NW THRU THE DAY. HI
PRES RIDGE OVER THE GOMEX WILL MERGE WITH THE POST FRONTAL RIDGE
OVER THE DEEP SOUTH...RESULTING IN A MODERATE TO FRESH NWRLY BREEZE
EARLY IN THE DAY THAT WILL STEADILY VEER TO N/NW BY SUNSET...THEN
BCMG A GENTLE TO MODERATE N/NE BREEZE OVERNIGHT. SEAS BUILDING TO
4-5FT NEARSHORE AND 5-6FT OFFSHORE...UP TO 7FT IN THE GULF STREAM.
SUN-SUN NIGHT...THE CONSOLIDATED RIDGE WILL PUSH OFF THE MID ATLC
COAST...ALLOWING A MODERATE TO FRESH NERLY BREEZE TO DVLP THRU THE
DAY...BCMG E/SE OVERNIGHT. SEAS BUILDING TO 5-7FT NEARSHORE AND
6-8FT OFFSHORE. INCRSG PRECIP CHANCES WITH THE DVLPG ONSHORE
FLOW...SLGT CHC SHRAS THRU THE DAY...BCMG CHC OVERNIGHT.
&&
.FIRE WEATHER...
VERY DRY AIR MASS IN PLACE THRU MIDWEEK WITH MIN RH VALUES DROPPING
BLO 35PCT FOR 6-8HRS THRU THU AFTN...BTWN 25-30PCT FOR 4-6HRS FROM
INDIAN RIVER/OSCEOLA CO NWD. MODERATE/GUSTY NW WINDS TODAY WILL
PROMOTE VERY HIGH AFTN DISPERSION VALUES. POOR TO FAIR DISPERSION ON
THU AS A HI PRES RIDGE BUILDS OVER CENTRAL FL...ALLOWING TRANSPORT
WINDS TO DIMINISH WHILE REDUCING MIXING HEIGHTS TO LESS THAN 3KFT.
OVERALL FIRE THREAT WILL REMAIN LOW...HOWEVER...AS ERC VALUES ARE
EXPECTED TO REMAIN IN THE L/M TEENS TODAY. DIMINISHING WINDS ON THU
WILL REDUCE OVERALL FIRE THREAT...ERC VALUES NOT ANTICIPATED TO REACH
CRITICAL LVLS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 57 34 59 44 / 0 0 10 10
MCO 59 37 64 44 / 0 0 10 10
MLB 60 36 63 45 / 0 0 10 10
VRB 60 37 64 43 / 0 0 10 10
LEE 58 36 65 46 / 0 0 0 10
SFB 58 35 63 44 / 0 0 10 10
ORL 58 39 64 45 / 0 0 10 10
FPR 60 38 63 43 / 0 0 10 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR FLAGLER
BEACH TO JUPITER INLET 0-20 NM.
SMALL CRAFT ADVISORY UNTIL 4 AM EST THURSDAY FOR FLAGLER BEACH
TO JUPITER INLET 20-60 NM.
&&
$$
SHORT TERM/AVIATION...CRISTALDI
LONG TERM/IMPACT WX...BRAGAW
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
350 AM EST WED FEB 10 2016
.DISCUSSION...
CURRENT...
LARGE DEEP LAYER LOW CONTINUES TO COVER THE BREADTH OF THE ERN CONUS
WITH COLD HIGH PRES AT THE SFC BUILDING EWD FROM THE CTRL CONUS INTO
THE ERN CONUS/FL. THE STRONG/GUSTY W-NW FLOW OF TUE HAS EASED SOME
OVER LAND SINCE SUNSET...BUT STILL REMAINS BREEZY IN A FEW LOCATIONS
OVER THE CTRL CWA NEAR THE COAST. A LARGE SWATH OF CI/CS OVHD HAS
BEEN SLOWLY SHIFTING S/E...BUT CONTINUES ACROSS THE SRN HALF OF THE
CWA IN RR QUAD OF DEPARTING ST JETMAX IN EXCESS OF 150KT. THIS IS
HELPING TO KEEP TEMPS A BIT ABOVE THE CURRENT FCST FOR THE CENTRAL
AND ESPECIALLY THE SRN CWA. ALSO WINDS HAVE DROPPED OFF SOME WHERE
THE CURRENT ADVISORY FOR WIND CHILLS IS IN EFFECT... AND
CONSEQUENTLY WCI`S ARE AOA 40F THERE ATTM. WHILE THERE IS STILL TIME
FOR THESE VALUES TO REACH FCST OF U20S-L30S...WILL TAKE A CLOSE LOOK
AT ZFP ISSUANCE TIME TO SEE IF ANY ADJUSTMENTS NEED TO BE MADE.
TODAY/TONIGHT...
MODEL GUIDANCE REMAINS CONSISTENT IN SHOWING THE SRN LOBE OF THE
COLD HIGH SLIDING EAST ACROSS THE GOMEX AND OVER FL BY LATE TONIGHT.
H30-H20 RH PROGS INDICATE THAT THE HIGH CLOUDS WILL SHIFT S/E OF THE
SRN CWA LATER THIS MORNING...LEAVING SUNNY SKIES... BUT CONTINUE
COLD TEMPS IN ITS WAKE. MOS GUID CONTINUES TO INDICATE U50S FOR THE
NRN HALF CWA AND AROUND 60F TO THE SOUTH. IT ALSO SHOWS BLYR WINDS
OF AROUND 17-18KT ACROSS THE NRN HALF CWA THIS AFTN WHICH IS RIGHT
AT THE CUSP FOR A LAKE WIND ADVISORY. GIVEN THAT MOS HAS BEEN
PERFORMING PRETTY WELL WITH WINDS THE LAST SEVERAL DAYS...WILL GO
AHEAD AND ISSUE NPW/LWA FROM OSCEOLA/BREVARD NWD FOR THIS AFTN.
WIDESPREAD MINS IN THE 30S TONIGHT AS SFC HIGH CRESTS OVER THE CWA
AROUND 12Z THU. SETUP CONTINUES TO LOOK PRETTY DECENT FOR FROST AND
A FEW POCKETS OF (NEAR) FREEZING TEMPS FOR THE INTERIOR. BEST CHANCE
REMAINS AROUND THE LAKE GEORGE/OCALA FOREST REGION...AND SUBSEQUENT
SHIFTS MAY NEED TO CONSIDER A FREEZING WARNING FOR THAT AREA BASED
ON 12Z MOS TEMP TRENDS. MAY ALSO NEED A FROST ADVISORY FOR A GOOD
CHUNK OF THE CWA FOR LATE TONIGHT.
THU-FRI...
QUIET WX PATTERN TO END THE WORK WEEK AS A WEAK HI PRES RIDGE OVER
THE SRN PLAINS IS PULLED INTO THE GOMEX BY THE DEPARTING JET STREAK
OVER THE SRN GOMEX/CENTRAL FL PENINSULA. STRONG SUBSIDENCE INVERSION
IN THE H90-H60 LYR WILL KEEP PWAT VALUES WELL BLO 1.0" WHILE
LIMITING VERTICAL MIXING TO LESS THAN 10KFT.
NWRLY WINDS ON THU WILL KEEP MAX TEMPS IN THE L/M60S...ABOUT 10F BLO
AVG. LIGHT WINDS THU NIGHT AS THE RIDGE AXIS EXPANDS OVER THE
CENTRAL PENINSULA...RESULTING IN GOOD RADIATIONAL COOLING.
HOWEVER...A SLIGHT W/SW COMPONENT WILL ALLOW MINS TO RECOVER INTO
THE L/M40S OVER MOST OF THE CWA...THOUGH POCKETS OF U30S PSBL IN
WIND PROTECTED AREAS N OF I-4 AS WELL AS THE KISSIMMEE PRAIRIE.
W/SWRLY FLOW TO CONT ON FRI AS THE RIDGE AXIS IS SHUNTED INTO S FL
BY A BROAD STORM SYSTEM FCST TO DVLP OUT OF THE NEXT SHORT WAVE BY
LATE WEEK...MAX/MIN TEMPS TO RECOVER TO WITHIN A DEG OR TWO OF CLIMO
AVGS...L/M70S AND U40S/L50S RESPECTIVELY.
SAT-TUE...UPDATE TO FOLLOW.
&&
.AVIATION...
VFR. BKN-OVC250 KMLB-KSUA SHIFTS S/E THROUGH 12-14Z. SWATH OF
SHALLOW MARINE SC AIDED BY H50 VORT LOBE WILL PRODUCE FAST MOVING
DECK NEAR BKN050 AROUND ISM-MCO SWD THROUGH ROUGHLY THE SAME TIME
PERIOD...AND MAY EXTEND EWD TO MLB-SUA. OTRW...W-NW WINDS FROM ABOUT
280-290 WILL INCREASE TO 16-18KT/G23-25KT THIS AFTERNOON.
&&
.MARINE...
TODAY/TONIGHT...GLW WILL BE ALLOWED TO EXPIRE AT 09Z/4AM AND DON`T
ANTICIPATE ANY CHGS FORTHCOMING TO THE SCA FOR EITHER THE NEAR SHORE
OR OFFSHORE WATERS. EVEN AT SPEEDS OF 20-25KT...OFFSHORE COMPONENT
TO WINDS (WHICH HAVE BEEN RUNNING CLOSE TO 290 DEG) WILL CONTINUE TO
KEEP HIGHER SEAS WELL AWAY FROM THE COAST. DATA FROM BUOY 41009
SHOWS 7FT SEAS REMAIN CONFINED RIGHT AROUND AND BEYOND 20NM FROM
SHORE. THE SCA OUT TO 20NM WILL TRANSITION TO A CAUTIONARY STMT AT
15Z/10AM...WHILE THE SCA BEYOND 20NM WILL CONTINUE THROUGH 09Z/4AM
THU. SEAS 5-7FT NEAR SHORE AND 7-9FT OFFSHORE WILL GRADUALLY SUBSIDE
TO 4-5FT NEAR SHORE AND 6-7FT OFFSHORE BY TONIGHT.
THU-THU NIGHT...DIMINISHING WINDS THRU THE DAY AS A HI PRES RIDGE
OVER THE GOMEX NUDGES ITS WAY INTO THE FL PENINSULA/NRN BAHAMAS.
MODERATE TO FRESH N/NW BREEZE AT DAYBREAK BCMG GENTLE TO MODERATE BY
MIDDAY...THEN A LIGHT TO GENTLE NRLY BREEZE THRU SUNSET. POSITION
OF THE RIDGE AXIS JUST S OF THE I-4 CORRIDOR WOULD GENERATE VRBL
WINDS BLO 10KTS OVERNIGHT... W/SW FROM THE CAPE NWD...N/NE FROM THE
CAPE SWD. SEAS SUBSIDING FROM 4-6FT NEARSHORE AND 5-7FT OFFSHORE
EARLY IN THE DAY TO 2-4FT NEARSHORE AND 3-5FT OFFSHORE ARND
SUNSET...THEN 2-4FT AREAWIDE OVERNIGHT.
FRI-FRI NIGHT...BROAD STORM SYSTEM DVLPG OVER NEW ENGLAND AND OFF
THE MID ATLC COAST WILL SHUNT THE RIDGE AXIS INTO S FL/FL STRAITS.
RELATIVELY TIGHT PGRAD ON THE N FLANK OF THE RIDGE WILL GENERATE A
GENTLE TO MODERATE W/SW BREEZE FROM SEBASTIAN INLET NWD THRU THE
DAY...BCMG MODERATE TO FRESH WRLY BREEZE AFT SUNSET AND OVERNIGHT. S
OF SEBASTIAN INLET...PGRAD WILL BE RELATIVELY WEAK THRU THE DAY...
RESULTING INT A LIGHT WRLY BREEZE. HOWEVER...PGRAD WILL TIGHTEN
OVERNIGHT AS THE RIDGE AXIS MIGRATES INTO THE FL STRAITS...ALLOWING
THE MODERATE TO FRESH WRLY BREEZE TO EXPAND INTO THE SRN LEG BY
DAYBREAK. OFFSHORE BREEZE WILL LIMIT NEARSHORE SEAS TO 2-3FT...
OFFSHORE SEAS BUILDING FROM 2-3FT TO 3-4FT THRU THE DAY...THEN TO
4-5FT OVERNIGHT.
SAT-SAT NIGHT...DRY FRONTAL BOUNDARY WILL PUSH THRU THE LCL ATLC
WATERS...ALLOWING WINDS TO FRESHEN OUT OF THE NW THRU THE DAY. HI
PRES RIDGE OVER THE GOMEX WILL MERGE WITH THE POST FRONTAL RIDGE
OVER THE DEEP SOUTH...RESULTING IN A MODERATE TO FRESH NWRLY BREEZE
EARLY IN THE DAY THAT WILL STEADILY VEER TO N/NW BY SUNSET...THEN
BCMG A GENTLE TO MODERATE N/NE BREEZE OVERNIGHT. SEAS BUILDING TO
4-5FT NEARSHORE AND 5-6FT OFFSHORE...UP TO 7FT IN THE GULF STREAM.
SUN-SUN NIGHT...THE CONSOLIDATED RIDGE WILL PUSH OFF THE MID ATLC
COAST...ALLOWING A MODERATE TO FRESH NERLY BREEZE TO DVLP THRU THE
DAY...BCMG E/SE OVERNIGHT. SEAS BUILDING TO 5-7FT NEARSHORE AND
6-8FT OFFSHORE. INCRSG PRECIP CHANCES WITH THE DVLPG ONSHORE
FLOW...SLGT CHC SHRAS THRU THE DAY...BCMG CHC OVERNIGHT.
&&
.FIRE WEATHER...
VERY DRY AIR MASS IN PLACE THRU MIDWEEK WITH MIN RH VALUES DROPPING
BLO 35PCT FOR 6-8HRS THRU THU AFTN...BTWN 25-30PCT FOR 4-6HRS FROM
INDIAN RIVER/OSCEOLA CO NWD. MODERATE/GUSTY NW WINDS TODAY WILL
PROMOTE VERY HIGH AFTN DISPERSION VALUES. POOR TO FAIR DISPERSION ON
THU AS A HI PRES RIDGE BUILDS OVER CENTRAL FL...ALLOWING TRANSPORT
WINDS TO DIMINISH WHILE REDUCING MIXING HEIGHTS TO LESS THAN 3KFT.
OVERALL FIRE THREAT WILL REMAIN LOW...HOWEVER...AS ERC VALUES ARE
EXPECTED TO REMAIN IN THE L/M TEENS TODAY. DIMINISHING WINDS ON THU
WILL REDUCE OVERALL FIRE THREAT...ERC VALUES NOT ANTICIPATED TO REACH
CRITICAL LVLS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 57 34 59 44 / 0 0 10 10
MCO 59 37 64 44 / 0 0 10 10
MLB 60 36 63 45 / 0 0 10 10
VRB 60 37 64 43 / 0 0 10 10
LEE 58 36 65 46 / 0 0 0 10
SFB 58 35 63 44 / 0 0 10 10
ORL 58 39 64 45 / 0 0 10 10
FPR 60 38 63 43 / 0 0 10 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR FLAGLER
BEACH TO VOLUSIA-BREVARD COUNTY LINE 0-20 NM-SEBASTIAN
INLET TO JUPITER INLET 0-20 NM-VOLUSIA-BREVARD COUNTY LINE
TO SEBASTIAN INLET 0-20 NM.
SMALL CRAFT ADVISORY UNTIL 4 AM EST THURSDAY FOR SEBASTIAN INLET
TO JUPITER INLET 20-60 NM.
SMALL CRAFT ADVISORY UNTIL 4 AM EST THURSDAY FOR FLAGLER BEACH
TO VOLUSIA-BREVARD COUNTY LINE 20-60 NM-VOLUSIA-BREVARD
COUNTY LINE TO SEBASTIAN INLET 20-60 NM.
GALE WARNING UNTIL 4 AM EST EARLY THIS MORNING FOR FLAGLER BEACH
TO VOLUSIA-BREVARD COUNTY LINE 20-60 NM-VOLUSIA-BREVARD
COUNTY LINE TO SEBASTIAN INLET 20-60 NM.
&&
$$
SHORT TERM/AVIATION...CRISTALDI
LONG TERM/IMPACT WX...BRAGAW
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
908 PM CST THU FEB 11 2016
.UPDATE...
ISSUED AT 908 PM CST THU FEB 11 2016
Light snow is just now beginning to move into western parts of
central Illinois, even though radar indicates it should already
be occurring. Observations show very few lower clouds so if any
light snow is occurring out there, it is flurries and the
observational sites are not picking it up yet. Still thinking that
some light snow will occur in the southwestern parts of the CWA
overnight, so believe current forecast still looks good for the
remainder of the night. May make some tweaks to overnight low
temps in the southeast, but remainder of the area, current
forecast looks fine. Update out shortly.
&&
.SHORT TERM...(Tonight)
ISSUED AT 323 PM CST THU FEB 11 2016
A fast moving clipper will produce light snow starting this evening
across western Illinois, with most of the focused lift overnight
primarily remaining across our southwestern counties. The general
trend in the 12z models has been to focus the better chances of
measurable snowfall over our southwestern and southern counties.
Have increased PoPs to likely in a narrow corridor southwest of a
line from Jacksonville to Effingham, progressing from SW to SE with
time overnight. The HRRR is the farthest southwest with the latest
updated path of forcing for precip, with the NAM80, Canadian GEM,
and ECMWF still extending at least some snow accumulation across all
of our CWA except the far NE counties NE of CMI. The NAM12 is
similar to the HRRR in limiting snow to the SW half of our CWA. Have
reduced the PoPs in our N and NE counties, north of I-74, to slight
chance. Chance PoPs were limited to generally south of a line from
Galesburg to Lincoln to Paris. Snow amounts from Jacksonville to
Effingham could reach between a half inch and one inch, with a
dusting to a half inch as far north as Rushville to Lincoln to
Decatur. South to southwest winds should remain less than 10 mph
during the snowfall, so drifting should not be a big problem
overnight.
Low temps tonight will generally settle out in the mid-teens, as
cloud cover limits the diurnal swing to only around a 10 degree drop-
off.
.LONG TERM...(Friday through Thursday)
ISSUED AT 323 PM CST THU FEB 11 2016
Friday may start out with a few lingering snow showers south of
I-70, but little additional accumulation is expected after
sunrise. The bigger story will be the arrival of very cold air on
increasing northwest winds Friday afternoon, as strong pressure
rises develop ahead of the surface high center. The tight pressure
gradient will produce wind gusts over 30 mph at times, which could
cause minor drifting of the snowfall from tonight, so slippery
travel could develop from that Friday afternoon and evening.
Wind chills late Friday night will drop very close to advisory
levels of -15F north of Peoria, with wind chills below zero in all
of our forecast area. Actual air temps will be range from zero to 8
above zero, but NW winds will remain strong enough to push wind
chills well below zero.
The next main concern will be the system for Sunday into Monday.
Model differences remain with the 12z model updates. The Canadian
GEM has started showing the splitting of energy as the trough
reaches Illinois, similar to what the ECMWF was showing yesterday.
The ECMWF has changed and now maintains the trough energy across
Illinois Sunday evening, with total QPF amounts that support snow
amounts of 1 to 2". The Canadian GEM QPF amounts support around 1
inch west of I-55, with little to no snow accum east of I-55. The
GFS remains the only model that develops a distinct surface
low/circulation that tracks across northern IL Sunday evening, with
total QPF amounts that support snowfall of 4" to 7" in our northern
counties, and 3-4" in the south. The 12z NAM now includes forecast
info through 6 pm Sunday, and is showing plenty of snow as well,
despite no surface low moving across IL. The NAM has 3-5" across our
counties for just the first 12 hours of the event through 6 pm
Sunday. We have increased PoPs into the likely category for Sunday
nearly everywhere, and likely PoPs east of I-57 Sunday night.
Our compromise forecast for QPF came out to 0.23-0.30", correlating
to snowfall amounts of 2-4", with the higher totals from Peoria and
north. There still remains quite a bit of uncertainty with how much
moisture will fall, so updates to QPF and resultant snow accums are
likely with subsequent model runs.
The accumulating snows should primarily be done by Monday morning,
but lingering light snow or flurries could continue into afternoon.
If precip does linger into the afternoon, the snow may mix
with or change to rain.
All of the extended models show a low deepening south of Illinois on
Monday, and progressing up into the Appalachian mountains Monday
night, with precip mainly southeast of our area. However, the
blended initialization kept slight chance PoPs in the eastern half
of Illinois Monday night through Tuesday night, mainly due to that
strong system.
A warming trend is indicated for next week, as upper level ridging
gradually pushes east into Illinois. We should see mid-level warming
increase enough to support high temps climbing into the upper 30s to
low 40s Tuesday and Wed, with sunshine and mid 40s to around 50 for
Thursday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
ISSUED AT 551 PM CST THU FEB 11 2016
All sites will begin with mid and high clouds this evening, but
snow, along with lower cigs and vis will move into the area in a
few hours. Current radar shows most of the snow in central and
south central IA. Models differ on where most of snow will fall
and how far north/east it will occur in central IL. Will have
lightest snow along the PIA/BMI/CMI line with only going down to
3sm. DEC will have going down to 2sm and SPI down to 1.5sm. 5-8
hrs with SPI lasting longest since it will be closest to the
heavier band of snow. Cigs will drop to lower MVFR during the snow
and vis at SPI will be just above 1sm. Once snow stops, lower cigs
will remain but then scatter out during the afternoon. Winds will
be light most of the period, but then increase once snow ends and
be gusty. Wind directions will be southerly, then becoming
southwest, then west- northwesterly.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Auten
SHORT TERM...Shimon
LONG TERM...Shimon
AVIATION...Auten
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
551 PM CST THU FEB 11 2016
.SHORT TERM...(Tonight)
ISSUED AT 323 PM CST THU FEB 11 2016
A fast moving clipper will produce light snow starting this evening
across western Illinois, with most of the focused lift overnight
primarily remaining across our southwestern counties. The general
trend in the 12z models has been to focus the better chances of
measurable snowfall over our southwestern and southern counties.
Have increased PoPs to likely in a narrow corridor southwest of a
line from Jacksonville to Effingham, progressing from SW to SE with
time overnight. The HRRR is the farthest southwest with the latest
updated path of forcing for precip, with the NAM80, Canadian GEM,
and ECMWF still extending at least some snow accumulation across all
of our CWA except the far NE counties NE of CMI. The NAM12 is
similar to the HRRR in limiting snow to the SW half of our CWA. Have
reduced the PoPs in our N and NE counties, north of I-74, to slight
chance. Chance PoPs were limited to generally south of a line from
Galesburg to Lincoln to Paris. Snow amounts from Jacksonville to
Effingham could reach between a half inch and one inch, with a
dusting to a half inch as far north as Rushville to Lincoln to
Decatur. South to southwest winds should remain less than 10 mph
during the snowfall, so drifting should not be a big problem
overnight.
Low temps tonight will generally settle out in the mid-teens, as
cloud cover limits the diurnal swing to only around a 10 degree drop-
off.
.LONG TERM...(Friday through Thursday)
ISSUED AT 323 PM CST THU FEB 11 2016
Friday may start out with a few lingering snow showers south of
I-70, but little additional accumulation is expected after
sunrise. The bigger story will be the arrival of very cold air on
increasing northwest winds Friday afternoon, as strong pressure
rises develop ahead of the surface high center. The tight pressure
gradient will produce wind gusts over 30 mph at times, which could
cause minor drifting of the snowfall from tonight, so slippery
travel could develop from that Friday afternoon and evening.
Wind chills late Friday night will drop very close to advisory
levels of -15F north of Peoria, with wind chills below zero in all
of our forecast area. Actual air temps will be range from zero to 8
above zero, but NW winds will remain strong enough to push wind
chills well below zero.
The next main concern will be the system for Sunday into Monday.
Model differences remain with the 12z model updates. The Canadian
GEM has started showing the splitting of energy as the trough
reaches Illinois, similar to what the ECMWF was showing yesterday.
The ECMWF has changed and now maintains the trough energy across
Illinois Sunday evening, with total QPF amounts that support snow
amounts of 1 to 2". The Canadian GEM QPF amounts support around 1
inch west of I-55, with little to no snow accum east of I-55. The
GFS remains the only model that develops a distinct surface
low/circulation that tracks across northern IL Sunday evening, with
total QPF amounts that support snowfall of 4" to 7" in our northern
counties, and 3-4" in the south. The 12z NAM now includes forecast
info through 6 pm Sunday, and is showing plenty of snow as well,
despite no surface low moving across IL. The NAM has 3-5" across our
counties for just the first 12 hours of the event through 6 pm
Sunday. We have increased PoPs into the likely category for Sunday
nearly everywhere, and likely PoPs east of I-57 Sunday night.
Our compromise forecast for QPF came out to 0.23-0.30", correlating
to snowfall amounts of 2-4", with the higher totals from Peoria and
north. There still remains quite a bit of uncertainty with how much
moisture will fall, so updates to QPF and resultant snow accums are
likely with subsequent model runs.
The accumulating snows should primarily be done by Monday morning,
but lingering light snow or flurries could continue into afternoon.
If precip does linger into the afternoon, the snow may mix
with or change to rain.
All of the extended models show a low deepening south of Illinois on
Monday, and progressing up into the Appalachian mountains Monday
night, with precip mainly southeast of our area. However, the
blended initialization kept slight chance PoPs in the eastern half
of Illinois Monday night through Tuesday night, mainly due to that
strong system.
A warming trend is indicated for next week, as upper level ridging
gradually pushes east into Illinois. We should see mid-level warming
increase enough to support high temps climbing into the upper 30s to
low 40s Tuesday and Wed, with sunshine and mid 40s to around 50 for
Thursday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
ISSUED AT 551 PM CST THU FEB 11 2016
All sites will begin with mid and high clouds this evening, but
snow, along with lower cigs and vis will move into the area in a
few hours. Current radar shows most of the snow in central and
south central IA. Models differ on where most of snow will fall
and how far north/east it will occur in central IL. Will have
lightest snow along the PIA/BMI/CMI line with only going down to
3sm. DEC will have going down to 2sm and SPI down to 1.5sm. 5-8
hrs with SPI lasting longest since it will be closest to the
heavier band of snow. Cigs will drop to lower MVFR during the snow
and vis at SPI will be just above 1sm. Once snow stops, lower cigs
will remain but then scatter out during the afternoon. Winds will
be light most of the period, but then increase once snow ends and
be gusty. Wind directions will be southerly, then becoming
southwest, then west- northwesterly.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Shimon
LONG TERM...Shimon
AVIATION...Auten
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
922 PM EST THU FEB 11 2016
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 330 PM EST THU FEB 11 2016
A COLD UPPER TROUGH OVER ONTARIO AND THE ST. LAWRENCE VALLEY WILL KEEP US
UNDER A NORTHWEST FLOW ALOFT AND TEMPERATURES COLDER THAN NORMAL THROUGH
EARLY NEXT WEEK. A CLIPPER WILL GIVE US A CHANCE OF LIGHT SNOW TOWARDS
DAYBREAK OVER WESTERN SECTIONS AND MOST AREAS FRIDAY. LAKE EFFECT
SNOW SHOWERS MAY LINGER TO MIDDAY SATURDAY ACROSS OUR NORTHEAST.
COLD HIGH PRESSURE WILL BUILD EAST ACROSS OUR REGION SATURDAY AND
SATURDAY NIGHT. AN APPROACHING AREA OF LOW PRESSURE WILL SPREAD
SNOW ACROSS OUR REGION SUNDAY INTO MONDAY. ANOTHER SYSTEM WILL
BRING A CHANCE OF SNOW MONDAY AND MONDAY NIGHT. FINALLY A FOURTH
SYSTEM WILL BRING A CHANCE OF SNOW OR MIXED PRECIPITATION AROUND THE
MIDDLE OF NEXT WEEK. TEMPERATURES WILL BEGIN TO MODERATE TOWARDS THE
MIDDLE OF NEXT WEEK AS OUR UPPER FLOW BECOMES MORE ZONAL.
&&
.NEAR TERM.../TONIGHT AND FRIDAY/
ISSUED AT 822 PM EST THU FEB 11 2016
GOING FORECAST IS IN EXCELLENT SHAPE. FLAKES MAY FLY ACROSS PORTIONS
OF CENTRAL INDIANA BY THE MORNING RUSH. FEEL CHANCE POPS HANDLE THIS
BEST HOWEVER AS THERE IS A LOT OF NEAR SURFACE DRY AIR TO OVERCOME.
WILL HAVE TO MONITOR FOR POSSIBLE IMPACTS TO FRIDAY MORNING COMMUTE
ACROSS THE AREA...ESPECIALLY AS HRRR AND NAM PROFILES INDICATE FIRST
FLAKES MAY BEGIN REACHING THE GROUND DURING THE HEART OF THE
COMMUTE. HOWEVER...RATES APPEAR UNLIKELY TO BE SUCH THAT RAPID
ACCUMULATION WOULD OCCUR...WHICH WOULD LIMIT POTENTIAL IMPACT.
PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 330 PM EST THU FEB 11 2016
HIGH PRESSURE CENTERED OVER ILLINOIS WILL MOVE EAST ACROSS INDIANA THIS
EVENING AND ON TO THE EAST BY MONDAY. A WEAK CLIPPER OVER THE UPPER
MIDWEST AND NORTHERN PLAINS WILL MOVE TO THE MIDDLE MISSISSIPPI VALLEY
LATE TONIGHT AND ACROSS THE OHIO VALLEY FRIDAY.
MOSTLY CLEAR CONDITIONS WERE OCCURRING ACROSS WESTERN SECTIONS THIS AFTERNOON
WHILE PARTLY CLOUDY CONDITIONS WERE THE RULE IN THE EAST. MID/HIGH CLOUDS
OVER THE MIDDLE MISSISSIPPI VALLEY WILL MOVE OUR WAY AND THICKEN OVERNIGHT.
ANY SNOW FROM THE CLIPPER PROBABLY WON`T REACH OUR AREA UNTIL AFTER 09Z AND
THIS WILL BE MAINLY ACROSS WESTERN AND SOUTHWEST AREAS.
SCATTERED LIGHT SNOW SHOWERS WILL SPREAD EAST ACROSS OUR REGION FRIDAY. AMOUNTS
WILL BE GENERALLY A QUARTER INCH. BUT SOME LAKE EFFECT SNOW SHOWERS ARE POSSIBLE
ACROSS OUR NORTHEAST LATE FRIDAY AS OUR FLOW BECOMES MORE NORTHERLY AND AMOUNTS
THERE WILL BE A LITTLE HIGHER BY LATE FRIDAY.
LOWERED TEMPERATURES SLIGHTLY CENTRAL AND EAST TONIGHT AS HIGH PRESSURE WILL
PROVIDE GOOD RADIATIONAL COOLING EARLY ON. OTHERWISE...A MOS BLEND OF TEMPERATURES
SEEM REASONABLE. WINDS WILL BE LIGHT TONIGHT AND THEN BECOME NORTHWEST WITH
GUSTS UP TO 25 MPH BY FRIDAY AFTERNOON AS A PRESSURE GRADIENT STRENGTHENS.
&&
.SHORT TERM.../FRIDAY NIGHT THROUGH SUNDAY/
ISSUED AT 330 PM EST THU FEB 11 2016
WE WILL REMAIN UNDER A COLD NORTHWEST FLOW FRIDAY NIGHT SATURDAY AS HIGH
PRESSURE OVER THE NORTHERN PLAINS BUILDS OUR WAY. MODELS INDICATE SOME FETCH OFF
OF LAKE MICHIGAN WHICH WILL PRODUCE SCATTERED LAKE EFFECT SNOW SHOWERS OVER
NORTHEAST SECTIONS. WHILE COLD AND DRY WEATHER WILL BE THE RULE ELSEWHERE.
MODELS INDICATE 850 TEMPERATURES OF -15 TO -21 CELSIUS SATURDAY AND -8 TO -12
CELSIUS SUNDAY. THIS WILL TRANSLATE TO HIGHS IN THE TEENS SATURDAY 20 TO 26
DEGREES SUNDAY. LOWS WILL BE MOSTLY IN THE SINGLE DIGITS BOTH FRIDAY AND
SATURDAY NIGHT. BUT LOWS NEAR ZERO ARE POSSIBLE SATURDAY NIGHT OVER NORTHEAST
SECTIONS AS CLOUDS MAY NOT ARRIVE THERE UNTIL LATE.
THE BIGGEST CONCERN WILL BE SNOW AMOUNTS SUNDAY AS AREA OF LOW PRESSURE MOVES
INTO THE UPPER MIDWEST AND A STRONGER CLIPPER MOVES OUR WAY. THE NAM/OPERATIONAL
GFS AND THE NEW EURO ALL INDICATE AN INCH OR TWO OF SNOW BY SUNDAY AFTERNOON...
WHILE THE CANADIAN HARDLY HAS ANYTHING AS MOST OF ITS PRECIPITATION IS FARTHER
SOUTHWEST. FOR NOW WILL GO WITH A BLEND. WILL RAISE POPS TO LIKELY OVER WEST
CENTRAL AND NORTHWEST AND GO WITH HIGH CHANCE POPS ELSEWHERE BY SUNDAY AFTERNOON.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 237 PM EST FEB 11 2016
AN ACTIVE WEATHER PATTERN IS IN PLACE FOR THE LONG TERM. MODEL
VARIABILITY WITH THIS SYSTEM HAS BEEN AND CONTINUES TO BE FAIRLY
HIGH...AS DESCRIBED FURTHER BELOW. ESSENTIALLY AN UPPER WAVE WILL
MOVE SOMEWHERE THROUGH THE GREAT LAKES WITH AN ASSOCIATED SURFACE
SYSTEM SOMEWHERE TO ITS SOUTH AND THIS WILL BRING SNOW CHANCES TO
THE AREA. HOW MUCH SNOW AND WHERE IS STILL VERY MUCH IN QUESTION.
GFS ENSEMBLE MEMBERS ARE CLUSTERING MORE WITH THE HIGHER AMOUNTS
OVER NORTHERN INDIANA WITH A FEW MEMBERS PUTTING THE MAX ACROSS
THE CENTRAL PART OF THE STATE. 24 HOUR MAX AMOUNTS IN THE GEFS
VARY FROM 2 INCHES TO AROUND 6 INCHES. THE 12Z OPERATIONAL GFS HAS
A MAX OF AROUND 4+ INCHES ACROSS THE NORTHERN THIRD OF THE STATE
WITH 2-3 INCH AMOUNTS CENTRAL AND SHARPLY LESS SOUTH. THE 12Z
ECMWF THOUGH SHOWS SNOWFALL MAXES TO THE NORTH AND SOUTH WITH THE
IND CWA IN A LOCAL MINIMUM WITH AROUND 1-1.5 INCHES OR LESS. ECM
RUNS HAVE BEEN BOUNCING FROM A SOLUTION WITH A MAX WELL SOUTH OF
THE FORECAST AREA TO HIGHEST AMOUNTS ACROSS THE SOUTHERN COUNTIES.
0Z CANADIAN ENSEMBLE AVERAGE FAVORS THE SOLUTION THAT PUTS THE MAX
WELL SOUTH OF THE AREA. 0Z GFS CIPS ANALOGS SHOW THE HIGHEST
PROBABILITY FOR 2 INCHES OR GREATER IS ACROSS THE NORTHERNMOST
COUNTIES OF THE FORECAST AREA AND PROBABILITIES TAPER OFF HEADING
SOUTH.
FORECAST MODELS ARE FAIRLY CONSISTENT IN SHOWING DECENT
FORCING DURING THE SUNDAY NIGHT PERIOD SO WILL INCREASE POPS TO
LIKELY DURING THAT TIME. AT THIS MOMENT THOUGH WILL NOT CHANGE
SNOWFALL AMOUNTS FROM THOSE GIVEN BY THE BLENDED INITIALIZATION.
SNOW CHANCES STAY AROUND FOR MONDAY THROUGH TUESDAY IN CYCLONIC
FLOW. SHOULD SEE A SLOW WARMING TREND THROUGH THE WEEK WITH SMALL
CHANCES FOR RAIN OR SNOW TUESDAY AND WEDNESDAY.
&&
.AVIATION /DISCUSSION FOR THE 120300Z KIND TAF UPDATE/...
ISSUED AT 922 PM EST THU FEB 11 2016
NO CHANGES MADE TO THE FORECAST AT THIS TIME. PREVIOUS DISCUSSION
FOLLOWS.
EXPECTING CEILINGS TO GRADUALLY FALL TONIGHT OVER THE
TERMINALS...FALLING BELOW 050 DURING THE PRE DAWN HOURS OF FRIDAY AS
A DISTURBANCE APPROACHES FROM THE NORTHERN PLAINS. SOME LIGHT SNOW
MAY BEGIN AFFECTING THE TERMINALS AFTER ABOUT 120900Z. IFR VISIBILITY
RESTRICTIONS ARE POSSIBLE TOWARDS/AFTER SUNRISE ON FRIDAY AS THIS
DISTURBANCE MOVES THROUGH BASED ON OBSERVATIONS UPSTREAM. HOWEVER...THE
AREA OF BEST LIFT IS QUITE NARROW AND THERE ARE UNCERTAINTIES REGARDING
THE TRACK OF THE BEST LIFT. AS A RESULT...CONFIDENCE IN IFR RESTRICTIONS
AT ANY PARTICULAR TERMINAL IS LOW AT THIS TIME.
SURFACE WINDS UNDER 6 KTS TONIGHT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH/NIELD
SHORT TERM...JH
LONG TERM...CP
AVIATION...JAS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
822 PM EST THU FEB 11 2016
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 330 PM EST THU FEB 11 2016
A COLD UPPER TROUGH OVER ONTARIO AND THE ST. LAWRENCE VALLEY WILL KEEP US
UNDER A NORTHWEST FLOW ALOFT AND TEMPERATURES COLDER THAN NORMAL THROUGH
EARLY NEXT WEEK. A CLIPPER WILL GIVE US A CHANCE OF LIGHT SNOW TOWARDS
DAYBREAK OVER WESTERN SECTIONS AND MOST AREAS FRIDAY. LAKE EFFECT
SNOW SHOWERS MAY LINGER TO MIDDAY SATURDAY ACROSS OUR NORTHEAST.
COLD HIGH PRESSURE WILL BUILD EAST ACROSS OUR REGION SATURDAY AND
SATURDAY NIGHT. AN APPROACHING AREA OF LOW PRESSURE WILL SPREAD
SNOW ACROSS OUR REGION SUNDAY INTO MONDAY. ANOTHER SYSTEM WILL
BRING A CHANCE OF SNOW MONDAY AND MONDAY NIGHT. FINALLY A FOURTH
SYSTEM WILL BRING A CHANCE OF SNOW OR MIXED PRECIPITATION AROUND THE
MIDDLE OF NEXT WEEK. TEMPERATURES WILL BEGIN TO MODERATE TOWARDS THE
MIDDLE OF NEXT WEEK AS OUR UPPER FLOW BECOMES MORE ZONAL.
&&
.NEAR TERM.../TONIGHT AND FRIDAY/
ISSUED AT 822 PM EST THU FEB 11 2016
GOING FORECAST IS IN EXCELLENT SHAPE. FLAKES MAY FLY ACROSS PORTIONS
OF CENTRAL INDIANA BY THE MORNING RUSH. FEEL CHANCE POPS HANDLE THIS
BEST HOWEVER AS THERE IS A LOT OF NEAR SURFACE DRY AIR TO OVERCOME.
WILL HAVE TO MONITOR FOR POSSIBLE IMPACTS TO FRIDAY MORNING COMMUTE
ACROSS THE AREA...ESPECIALLY AS HRRR AND NAM PROFILES INDICATE FIRST
FLAKES MAY BEGIN REACHING THE GROUND DURING THE HEART OF THE
COMMUTE. HOWEVER...RATES APPEAR UNLIKELY TO BE SUCH THAT RAPID
ACCUMULATION WOULD OCCUR...WHICH WOULD LIMIT POTENTIAL IMPACT.
PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 330 PM EST THU FEB 11 2016
HIGH PRESSURE CENTERED OVER ILLINOIS WILL MOVE EAST ACROSS INDIANA THIS
EVENING AND ON TO THE EAST BY MONDAY. A WEAK CLIPPER OVER THE UPPER
MIDWEST AND NORTHERN PLAINS WILL MOVE TO THE MIDDLE MISSISSIPPI VALLEY
LATE TONIGHT AND ACROSS THE OHIO VALLEY FRIDAY.
MOSTLY CLEAR CONDITIONS WERE OCCURRING ACROSS WESTERN SECTIONS THIS AFTERNOON
WHILE PARTLY CLOUDY CONDITIONS WERE THE RULE IN THE EAST. MID/HIGH CLOUDS
OVER THE MIDDLE MISSISSIPPI VALLEY WILL MOVE OUR WAY AND THICKEN OVERNIGHT.
ANY SNOW FROM THE CLIPPER PROBABLY WON`T REACH OUR AREA UNTIL AFTER 09Z AND
THIS WILL BE MAINLY ACROSS WESTERN AND SOUTHWEST AREAS.
SCATTERED LIGHT SNOW SHOWERS WILL SPREAD EAST ACROSS OUR REGION FRIDAY. AMOUNTS
WILL BE GENERALLY A QUARTER INCH. BUT SOME LAKE EFFECT SNOW SHOWERS ARE POSSIBLE
ACROSS OUR NORTHEAST LATE FRIDAY AS OUR FLOW BECOMES MORE NORTHERLY AND AMOUNTS
THERE WILL BE A LITTLE HIGHER BY LATE FRIDAY.
LOWERED TEMPERATURES SLIGHTLY CENTRAL AND EAST TONIGHT AS HIGH PRESSURE WILL
PROVIDE GOOD RADIATIONAL COOLING EARLY ON. OTHERWISE...A MOS BLEND OF TEMPERATURES
SEEM REASONABLE. WINDS WILL BE LIGHT TONIGHT AND THEN BECOME NORTHWEST WITH
GUSTS UP TO 25 MPH BY FRIDAY AFTERNOON AS A PRESSURE GRADIENT STRENGTHENS.
&&
.SHORT TERM.../FRIDAY NIGHT THROUGH SUNDAY/
ISSUED AT 330 PM EST THU FEB 11 2016
WE WILL REMAIN UNDER A COLD NORTHWEST FLOW FRIDAY NIGHT SATURDAY AS HIGH
PRESSURE OVER THE NORTHERN PLAINS BUILDS OUR WAY. MODELS INDICATE SOME FETCH OFF
OF LAKE MICHIGAN WHICH WILL PRODUCE SCATTERED LAKE EFFECT SNOW SHOWERS OVER
NORTHEAST SECTIONS. WHILE COLD AND DRY WEATHER WILL BE THE RULE ELSEWHERE.
MODELS INDICATE 850 TEMPERATURES OF -15 TO -21 CELSIUS SATURDAY AND -8 TO -12
CELSIUS SUNDAY. THIS WILL TRANSLATE TO HIGHS IN THE TEENS SATURDAY 20 TO 26
DEGREES SUNDAY. LOWS WILL BE MOSTLY IN THE SINGLE DIGITS BOTH FRIDAY AND
SATURDAY NIGHT. BUT LOWS NEAR ZERO ARE POSSIBLE SATURDAY NIGHT OVER NORTHEAST
SECTIONS AS CLOUDS MAY NOT ARRIVE THERE UNTIL LATE.
THE BIGGEST CONCERN WILL BE SNOW AMOUNTS SUNDAY AS AREA OF LOW PRESSURE MOVES
INTO THE UPPER MIDWEST AND A STRONGER CLIPPER MOVES OUR WAY. THE NAM/OPERATIONAL
GFS AND THE NEW EURO ALL INDICATE AN INCH OR TWO OF SNOW BY SUNDAY AFTERNOON...
WHILE THE CANADIAN HARDLY HAS ANYTHING AS MOST OF ITS PRECIPITATION IS FARTHER
SOUTHWEST. FOR NOW WILL GO WITH A BLEND. WILL RAISE POPS TO LIKELY OVER WEST
CENTRAL AND NORTHWEST AND GO WITH HIGH CHANCE POPS ELSEWHERE BY SUNDAY AFTERNOON.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 237 PM EST FEB 11 2016
AN ACTIVE WEATHER PATTERN IS IN PLACE FOR THE LONG TERM. MODEL
VARIABILITY WITH THIS SYSTEM HAS BEEN AND CONTINUES TO BE FAIRLY
HIGH...AS DESCRIBED FURTHER BELOW. ESSENTIALLY AN UPPER WAVE WILL
MOVE SOMEWHERE THROUGH THE GREAT LAKES WITH AN ASSOCIATED SURFACE
SYSTEM SOMEWHERE TO ITS SOUTH AND THIS WILL BRING SNOW CHANCES TO
THE AREA. HOW MUCH SNOW AND WHERE IS STILL VERY MUCH IN QUESTION.
GFS ENSEMBLE MEMBERS ARE CLUSTERING MORE WITH THE HIGHER AMOUNTS
OVER NORTHERN INDIANA WITH A FEW MEMBERS PUTTING THE MAX ACROSS
THE CENTRAL PART OF THE STATE. 24 HOUR MAX AMOUNTS IN THE GEFS
VARY FROM 2 INCHES TO AROUND 6 INCHES. THE 12Z OPERATIONAL GFS HAS
A MAX OF AROUND 4+ INCHES ACROSS THE NORTHERN THIRD OF THE STATE
WITH 2-3 INCH AMOUNTS CENTRAL AND SHARPLY LESS SOUTH. THE 12Z
ECMWF THOUGH SHOWS SNOWFALL MAXES TO THE NORTH AND SOUTH WITH THE
IND CWA IN A LOCAL MINIMUM WITH AROUND 1-1.5 INCHES OR LESS. ECM
RUNS HAVE BEEN BOUNCING FROM A SOLUTION WITH A MAX WELL SOUTH OF
THE FORECAST AREA TO HIGHEST AMOUNTS ACROSS THE SOUTHERN COUNTIES.
0Z CANADIAN ENSEMBLE AVERAGE FAVORS THE SOLUTION THAT PUTS THE MAX
WELL SOUTH OF THE AREA. 0Z GFS CIPS ANALOGS SHOW THE HIGHEST
PROBABILITY FOR 2 INCHES OR GREATER IS ACROSS THE NORTHERNMOST
COUNTIES OF THE FORECAST AREA AND PROBABILITIES TAPER OFF HEADING
SOUTH.
FORECAST MODELS ARE FAIRLY CONSISTENT IN SHOWING DECENT
FORCING DURING THE SUNDAY NIGHT PERIOD SO WILL INCREASE POPS TO
LIKELY DURING THAT TIME. AT THIS MOMENT THOUGH WILL NOT CHANGE
SNOWFALL AMOUNTS FROM THOSE GIVEN BY THE BLENDED INITIALIZATION.
SNOW CHANCES STAY AROUND FOR MONDAY THROUGH TUESDAY IN CYCLONIC
FLOW. SHOULD SEE A SLOW WARMING TREND THROUGH THE WEEK WITH SMALL
CHANCES FOR RAIN OR SNOW TUESDAY AND WEDNESDAY.
&&
.AVIATION /DISCUSSION FOR THE 120000Z TAFS/...
ISSUED AT 538 PM EST THU FEB 11 2016
EXPECTING CEILINGS TO GRADUALLY FALL TONIGHT OVER THE
TERMINALS...FALLING BELOW 050 DURING THE PRE DAWN HOURS OF FRIDAY AS
A DISTURBANCE APPROACHES FROM THE NORTHERN PLAINS. SOME LIGHT SNOW
MAY BEGIN AFFECTING THE TERMINALS AFTER ABOUT 120900Z. IFR VISIBILITY
RESTRICTIONS ARE POSSIBLE TOWARDS/AFTER SUNRISE ON FRIDAY AS THIS
DISTURBANCE MOVES THROUGH BASED ON OBSERVATIONS UPSTREAM. HOWEVER...THE
AREA OF BEST LIFT IS QUITE NARROW AND THERE ARE UNCERTAINTIES REGARDING
THE TRACK OF THE BEST LIFT. AS A RESULT...CONFIDENCE IN IFR RESTRICTIONS
AT ANY PARTICULAR TERMINAL IS LOW AT THIS TIME.
SURFACE WINDS UNDER 6 KTS TONIGHT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH/NIELD
SHORT TERM...JH
LONG TERM...CP
AVIATION...JAS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1250 AM EST WED FEB 10 2016
.SYNOPSIS...
ISSUED AT 1245 AM EST WED FEB 10 2016
LAKE EFFECT SNOW SHOWERS WILL CONTINUE OVERNIGHT AND WILL BE
LOCALLY HEAVY AT TIMES THROUGH DAYBREAK. SNOWFALL RATES OF 1 TO 2
INCHES PER HOUR ARE POSSIBLE IN THE STRONGEST BANDS. SNOW
SHOWERS WILL LESSEN IN INTENSITY BUT STILL PERSIST THROUGH THURSDAY.
WHILE MOST LOCATIONS SHOULD SEE AT LEAST SOME MEASURABLE SNOWFALL
DURING THIS PERIOD...THE MORE SIGNIFICANT AMOUNTS AND GREATEST
IMPACTS WILL BE CONFINED TO THE FAVORED LAKE EFFECT SNOW BELT
REGION. LOWS TONIGHT WILL BE IN THE TEENS WITH HIGHS WEDNESDAY IN
THE UPPER TEENS AND LOWER 20S.
&&
.UPDATE...
ISSUED AT 830 PM EST TUE FEB 9 2016
LOW LEVEL COLD ADVECTION WILL CONTINUE TO INCREASE OVER THE NEXT
SEVERAL HOURS...WITH LAKE RESPONSE STARTING TO BECOME MORE
APPARENT VIA OBSERVATIONS AND REGIONAL RADAR IMAGERY. RAP BUFR
SOUNDINGS CONTINUE TO INDICATE RISING INVERSION HEIGHTS THROUGH
AROUND 09Z. NATURE OF LAKE EFFECT HAS BEEN CELLULAR MULTIBAND
THIS EVENING AND WOULD SUSPECT INTENSITY TO PICK UP LATE EVENING
AS SYNOPTIC UPPER TROUGH APPROACHES. WEAK TO MODERATE SHEAR IN
CLOUD BEARING LAYER MAY CONTINUE TO PROMOTE MORE OF A MULTIBAND
SETUP THROUGH MUCH OF THE EARLY PART OF THE OVERNIGHT HOURS.
CONCERN THAT A MORE DOMINANT BAND MAY SETUP LATE TONIGHT INTO
EARLY WEDNESDAY MORNING PER RECENT HRRR TRENDS AS WEAK SYNOPTIC
TROUGH DEPARTS SOUTH OF THE LAKE ALLOWING SLIGHTLY MORE FAVORABLE
WIND FIELD ALONG WITH A PEAK IN LAKE INDUCED INSTABILITY.
CURRENTLY HAVE NO PLANS FOR HEADLINE CHANGES AT THIS TIME DUE TO
UNCERTAINTY IN POTENTIAL MORE DOMINANT PLACEMENT/INTENSITY LATE
TONIGHT/EARLY WEDNESDAY MORNING. ALSO HAVE NOT MADE SIGNIFICANT
CHANGES IN FORECASTED SNOW ACCUMS. ACCUMULATION EFFICIENCY HAS
STRUGGLED AWAY FROM THE LAKE THIS EVENING...ALTHOUGH INCREASING
MORE FAVORABLE THERMO PROFILES FOR SNOW GROWTH SHOULD BEGIN TO
COME INTO PLAY LATE EVENING/OVERNIGHT...AND THUS HESITANT TO
LOWER AMOUNTS TOO MUCH AT THIS TIME.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 258 PM EST TUE FEB 9 2016
LONG DURATION LAKE EFFECT SNOW EVENT BEGINNING LATE THIS AFTN AS
STRENGTHENING LOW LEVEL NW FLOW AND CAA OVERSPREADS LAKE MICHIGAN
AND NW PORTION OF OUR CWA. FAVORABLE FACTORS FOR LES TONIGHT INCLUDE
A DEEP MOIST LAYER FROM THE SFC-700MB, LITTLE SFC-850MB LAYER SHEAR,
A SHRTWV MOVG ACROSS THE AREA CAUSING INVERSION HEIGHTS TO RISE TO
AROUND 6KFT AND PROVIDING WK SYNOPTIC SCALE LIFT. SFC TROF
REFLECTION SHOULD ALSO MOVE SE ACROSS SRN LAKE MICHIGAN OVERNIGHT
STRENGTHENING BANDS AS LOW LEVEL CONVERGENCE ENHANCED, BUT ALSO
PSBLY CAUSING DOMINANT BANDS TO BECOME SOMEWHAT TRANSITORY.
MAIN NEGATIVE FACTOR OVERNIGHT AND THROUGH THE ENTIRE EVENT IS WK
LAKE INDUCED INSTABILITY OF <500J/KG. HIGH RES MODELS IN DECENT
AGREEMENT ON A COUPLE OF DOMINANT BANDS IMPACTING THE AREA, ONE
THROUGH CASS COUNTY MI AND SECOND IMPACTING SW BERRIEN, NW ST JOE
INDIANA, AND PSBLY NE LAPORTE. EXPECT GENERAL 2-4" SNOWFALL ACCUMS
IN THE ADVISORY AREA TONIGHT WITH LOCALLY HIGHER AMOUNTS PSBL IN
AREAS WHERE DOMINANT BANDS PERSIST THE LONGEST.
LOW LEVEL CAA EXPECTED TO CONT WED AS 850MB THERMAL TROF WITH -21C
AIR MOVES OVER THE LAKE. DESPITE THIS, LITTLE CHANGE IN LAKE INDUCED
INSTABILITY FCST AS WARMING OCCURS ABOVE INVERSION BASED AROUND
4.5KFT. WITH SOME DRYING OF THE COLUMN ALSO OCCURRING WED/WED NGT,
EXPECT ACCUMS IN THE ADVISORY AREA WILL BE A LITTLE LIGHTER THAN
TONIGHT, GENERALLY IN THE 1-3" RANGE EACH PERIOD. LAKE EFFECT SHOULD
FINALLY WIND DOWN THU AS SFC RIDGE BUILDS IN, INVERSION LOWERS, AND
LOW LEVELS CONT TO DRY OUT WITH ADDITIONAL ACCUMS EXPECTED TO BE <1"
IN THIS PERIOD. THUS, CONTD WITH A WINTER WX ADVISORY FOR THIS LAKE
EFFECT SNOW EVENT AS 12-24HR AMOUNTS EXPECTED TO GENERALLY BE BLO
WARNING CRITERIA, THOUGH STORM TOTALS (INCLUDING LAST NIGHT`S
SNOWFALL) WILL PRBLY BE CLOSE TO A FOOT IN PORTIONS OF THE ADVISORY
AREA.
FOR THE REST OF THE CWA, BRISK CYCLONIC NW FLOW SHOULD SUPPORT LAKE
EFFECT SNOW BANDS PENETRATING WELL INLAND TONIGHT THROUGH THURSDAY.
HWVR, TYPICAL OF LAKE EFFECT, ACCUMS WILL BE LESS FARTHER INLAND,
THOUGH SOME COUNTIES BORDERING THE ADVISORY MAY HAVE 3-5" STORM
TOTALS.
TEMPS WILL BE ON A GENERAL SLOW DECLINE OVER THE NEXT 36HRS AS
THERMAL TROF MOVES INTO THE AREA. LOWS TNGT SHOULD GENERALLY BE IN
THE TEENS WITH HIGHS WED IN THE UPPER TEENS TO L20S, AND LOWS WED
NGT AROUND 10 ABOVE. TEMPS SHOULD MODERATE SLIGHTLY THU AS WK WAA
DVLPS, WITH HIGHS EXPECTED IN THE L20S ACROSS THE AREA.
&&
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 343 PM EST TUE FEB 9 2016
A VERY DEEP COLD CORE LOW WILL BE IN THE VICINITY OF JAMES BAY
NEAR FAR SOUTHERN HUDSON BAY BY EARLY FRIDAY. THE GFS AND GFS
ENSEMBLES ALONG WITH THE ECMWF HAVE COME INTO GOOD AGREEMENT WITH
THIS SYSTEM BRINGING ANOTHER STRONG COLD FRONT ACROSS THE AREA
FOLLOWED BY LAKE EFFECT SNOW. DELTA T VALUES MAY EXCEED 25C
SATURDAY AS A FAVORABLE LAKE FETCH DEVELOPS. THE FETCH SHOULD BE
MORE NORTH/SOUTH THAN THIS ONGOING EVENT... WITH THE HEAVIEST
SNOWFALL OVER NORTHWEST INDIANA. HAVE RAISED SNOW CHANCES SATURDAY
IN THIS REGARD. THE RIDGE AXIS WILL TRANSLATE ACROSS THE AREA
SATURDAY NIGHT...CAUSING LAKE EFFECT SNOW TO SHIFT WEST.
KEPT TEMPERATURES VERY COLD FRIDAY NIGHT AND SATURDAY NIGHT...WITH
LOWS NEAR ZERO SATURDAY NIGHT WHERE SKIES ARE ABLE TO CLEAR OVER
FRESH SNOW COVER. MILDER WEATHER IS EXPECTED BY TUESDAY AS THE UPPER
FLOW BECOMES MORE HIGH ZONAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1243 AM EST WED FEB 10 2016
LAKE EFFECT SNOW SHOWERS AND IMPACTS AT TERMINALS MAIN FOCUS THIS
PACKAGE. KIWX 88D SHOWS STRONG BAND JUST NORTH OF KSBN AT ISSUANCE
TIME AND SINKING SOUTH. SHOULD SEE LIFR AND VLIFR CONDITIONS NEXT
FEW HOURS AS A FEW SFC REPORTS UNDER THIS BAND INDICATED NEAR
ZERO VISIBILITY AND HEAVY SNOWFALL RATES. HIRES MODELS INDICATE
THIS BAND TO WEAKEN OVERNIGHT OR AT LEAST TRANSLATE AWAY FROM
KSBN SO SLIGHTLY IMPROVED CONDITIONS AFTER 09-10Z. PERSISTENT NW
FLOW AND COLD AIR WILL LIKELY KEEP MVFR AND IFR CONDITIONS WITH
SNOW SHOWERS THROUGH REST OF PERIOD AT KSBN. KFWA REMAINS ON
EASTERN EDGE OF SNOW SHOWERS AND EXPECT VARIED CONDITIONS WITH
MVFR IN SNOW SHOWERS WITH BRIEF PERIODS OF IFR NOT OUT OF QUESTION
THROUGH MID MORNING WITH A FEW STRONGER SHOWERS THAT REMAIN
INTACT WELL INLAND.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER WEATHER ADVISORY UNTIL 10 AM EST /9 AM CST/ THURSDAY FOR
INZ003>005.
MI...WINTER WEATHER ADVISORY UNTIL 10 AM EST THURSDAY FOR MIZ077>079.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 10 AM EST THURSDAY FOR LMZ043-046.
&&
$$
UPDATE...MARSILI
SYNOPSIS...JT/LASHLEY
SHORT TERM...JT
LONG TERM...SKIPPER
AVIATION...LASHLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
803 PM CST THU FEB 11 2016
.UPDATE...
ISSUED AT 803 PM CST THU FEB 11 2016
NARROW BAND OF MOSTLY LIGHT SNOW HAS SET UP FROM JUST SW OF DMX
SE THROUGH CENTERVILLE AND OTTUMWA S-SE TO NEAR QUINCY IL AS SEEN
ON AREA RADARS. IN THE DVN FORECAST AREA...SNOW HAD BEGUN OVER
THE PAST HOUR IN FAIRFIELD WITH UPSTREAM VISIBILITIES AROUND 2 1/2
TO 3SM IN ADJACENT S CENTRAL IA . THE LATEST HRRR...RAP AND NAM
HIGH RES MODELS KEEP THIS AXIS OF LIGHT SNOW...CONFINED TO SE
IA...NE MO INTO W CENTRAL IL...MAINLY NORTH OF HIGHWAY 34. THIS IS
THE AXIS OF MAIN UPPER LEVEL FORCING...WHICH IS NUDGED UP AGAINST
A DEEP DRY AIRMASS TO THE NORTHEAST. SURFACE DEWPOINTS OVER
EASTERN IA AND POINTS EAST AND NORTH WERE ONLY IN THE SINGLE
DIGITS...AND THE KDVN 00Z/12 SOUNDING INDICATED A DEEP DRY LAYER
BELOW 700 MB.
THIS WILL LIKELY KEEP MEASURABLE SNOW LIMITED TO SE IA...FAR NW MO
AND W CENTRAL IL OVER THE NEXT SEVERAL HOURS AND HAVE BACKED DOWN
ON SNOW AMOUNTS OVER THE CENTRAL AND NORTH FOR OVERNIGHT TO TRACE
AMOUNTS AT BEST. WILL HAVE TO WATCH A WEAK AREA OF LIFT THE NW
FLOW ALOFT PRODUCING LIGHT SNOW IN THE MSP AREA FOR MUCH LATER
TONIGHT AS IT PROGRESSES TOWARD FAR EASTERN IA AND NW IL. WILL
HANDLE THIS WITH VERY LOW POPS AND KEEP A MENTION OF AT LEAST
FLURRIES IN ALL AREAS THROUGH THE OVERNIGHT.
&&
.SYNOPSIS...
ISSUED AT 327 PM CST THU FEB 11 2016
HIGH PRESSURE CENTERED OVER THE EASTERN CWA THIS AFTERNOON AS
LEADING TO CLEAR SKIES AND DRY WEATHER FOR MOST OF THE AREA. A
FAST MOVING CLIPPER IS FORECAST TO AFFECT THE AREA LATER TODAY AND
TONIGHT AND WILL BE THE MAIN FORECAST CONCERN IN THE SHORT TERM
FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 327 PM CST THU FEB 11 2016
MAIN FORECAST CONCERN FOR THE SHORT TERM ARE THE CHANCES FOR SNOW
ASSOCIATED WITH A FAST CLIPPER ACROSS THE AREA TODAY. DRY AIR IN
PLACE WITH THE HIGH OVERHEAD WILL LIMIT OVERALL SNOWFALL TOTALS TO
AROUND AN INCH...WITH LOCALLY HIGHER AMOUNTS JUST OVER AN INCH.
HIRES GUIDANCE IS IN GOOD AGREEMENT THAT THIS WILL START NEAR 00Z
AND BE OUT OF THE AREA BY 08Z.
GUIDANCE TODAY HELD STRONG WITH THE CONSENSUS ON TIMING AND
STRONGEST FORCING WILL REMAIN ACROSS OUR FAR SOUTHERN ZONES. WWD
HAS AROUND AN INCH OF SNOW FOR THIS AREA AND OUR FORECAST
REPRESENTS THIS. LATEST RUNS OF THE HRRR SUGGESTS THAT THE BEST
SNOW WILL BE OUT OF THE AREA BY 06Z WITH LINGERING FLURRIES
THROUGH 09Z ACROSS THE FAR SOUTHERN CWA. WINDS WILL REMAIN LIGHT
SO LITTLE TO NO IMPACTS ARE EXPECTED FROM THIS SNOW. ANY SNOW THAT
ACCUMULATES SHOULD BE DONE BY THE EARLY HOURS.
FRIDAY WILL BE QUIET AND SLIGHTLY WARMER..WITH CLEARING SKIES.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 327 PM CST THU FEB 11 2016
FRIDAY NIGHT...LATEST SUITE OF 12Z RUN MODELS SUGGEST 1045 MB ARCTIC
HIGH PRESSURE STILL ON TRACK TO SURGE DOWN THE UPPER TO MID MS
RIVER VALLEY FRI NIGHT INTO SAT WITH A SCOURING EFFECT. THIS
FEATURE TO COLD DUMP LLVL TEMPS/THICKNESS VALUES TO PRODUCE SUB-
ZERO LOWS ACRS MOST OF THE CWA...BUT SOME CONCERN THAT ONGOING
MIXING SFC WINDS IN INCOMING HIGH PRESSURE GRADIENT TO LIMIT A
COMPLETE BOTTOM OUT. BUT DUE TO BRUTE FORCE COLD AIR
ADVECTION...WILL STILL GO WITH LOWS FROM 5 TO NEAR 10 BELOW ZERO
ACRS THE NORTHWESTERN THIRD OF THE CWA...0 TO 5 BELOW ALONG AND
NORTH OF I80...AND TO THE LOW SINGLE DIGITS ABOVE ZERO IN THE
SOUTHERN CWA. SFC WINDS DECREASING TO 7-10 MPH TOWARD SUNRISE SAT
STILL TO PRODUCE ADVISORY LEVEL WIND CHILLS ACRS AT LEAST THE
NORTHWESTERN THIRD OF THE DVN CWA...AND POSSIBLY ALONG THE HWY 20
CORRIDOR IN NW IL.
SATURDAY AND SUNDAY...THE ARCTIC HIGH OVERHEAD WILL MAKE FOR
TEMPORARY CLEAR AND CALM/LIGHT WIND CONDITIONS FOR FIRST PART OF THE
DAY SAT...WITH HIGH CLOUDS ON THE INCREASE AS THE AFTERNOON
PROGRESSES. THIS AHEAD OF THE ORGANIZING SHORT WAVE UPPER TROF THAT
WILL LOOK TO PROPAGATE TOWARD THE SOUTHWESTERN GRT LKS AND MID MS
RIVER VALLEY ON SUNDAY IN BROADENING WEST-NORTHWESTERLY STEERING
FLOW. THE VARIOUS MEDIUM RANGE SOLUTIONS SUGGEST SOME TYPE OF
ASSOCIATED WARM AIR ADVECTION WING OF SNOW WILL LOOK TO TRY TO GET
INTO THE WESTERN OR SOUTHWESTERN CWA BY EARLY SAT EVENING...BUT
FEEL MODELS MAY BE TOO QUICK WITH THIS TAKING INTO ACCOUNT
STRENGTH OF DRY SFC RIDGE AXIS STILL ON THE MOVE OVER AND EAST OF
THE CWA AT THAT TIME. BUT BY MIDNIGHT SAT NIGHT...BOTH THE 12Z RUN
ECMWF AND GEM SUGGEST SOME LIGHT SNOW ACCUMS STARTING TO TAKE
PLACE ALREADY IN THE FAR SOUTHWESTERN CWA. AGAIN SIDING WITH THE
12Z GEM/ECMWF WHICH ARE IN DECENT AGREEMENT...THE WAA WING OF SNOW
AHEAD OF THE MAIN UPPER TROF WILL LOOK TO CONTINUE TO SPREAD
EASTWARD ACRS MUCH OF THE WESTERN 2/3S OF THE CWA THROUGH 12Z
SUNDAY...BUT MAY GET ERODED SOME AS IT DOES BY ONGOING DRY AIR IN
PLACE AND ALSO SOME IMPACT OF MUCH OF THE INITIAL LIFT GOING INTO
THE TOP-DOWN SATURATION PROCESS. THE LATEST GEM MAY HAVE THE BEST
HANDLE ON THIS IDEA WITH JUST A DUSTING TO HALF INCH WEST OF THE
MS RIVER BY 12Z SUNDAY...BUT WILL GO WITH A FEW TENTHS TO NEAR AN
INCH SOUTHWEST OF A LINE FROM DBQ...TO THE QUAD CITIES...AND TO
MACOMB IN WESTERN IL.
THEN THE MAIN SNOW EVENT WITH THE UPPER TROF WILL LOOK TO OCCUR ON
SUNDAY AND WILL CONTINUE TO ADJUST POPS UP INTO LIKELY OR EVEN
CATEGORICAL. BUT THE 12Z RUN AMERICAN MODELS/ESPECIALLY THE 12Z GFS/
WHICH HINT AT HIGH END ADVISORY OR EVEN LOW END WARNING CRITERIA
AMOUNT SNOWS BY SUNDAY EVENING COMBINING THE TWO SNOW MAKING
PROCESSES...SEEM TOO WET...TOO STRONG LOOKING AT MID AND UPPER LEVEL
JET DYNAMICS MORE FAVORABLE TO THE SOUTH...AND THEIR DEEP SATURATION
IN THE DENDRITIC GROWTH ZONE FOR MUCH OF SUNDAY MORNING INTO EARLY
AFTERNOON. SO CURRENTLY FAVOR A BLEND OF THE 12Z GEM/ECMWF MOISTURE
AND FORCING PROFILES WHICH SUGGEST MOST OF THE CWA TO GET 1-3 OR 2-4
INCHES OF SNOW BY SUNDAY EVENING. INCREASING SOUTH WINDS OF 15-20
MPH MAY PRODUCE SOME DRIFTING TROUBLE BY SUNDAY AFTERNOON AS
WELL...SO THERE MAY BE A NEED FOR AN EVENTUAL ADVISORY EVEN WITH THE
LIGHTER AMOUNTS PRODUCED BY THESE FAVORED SOLUTIONS. STILL 1-3 MORE
MODEL RUNS NEEDED TO FURTHER DEFINE THIS SNOW EVENT FOR MORE
CONFIDENCE.
MONDAY THROUGH NEXT THU...AS THE PASSING TROF CONTINUES TO EVOLVE
ALONG AND EAST OF THE REGION EARLY NEXT WEEK..RESULTANT MAJOR STORM
SHOULD TAKE OFF WELL TO THE EAST/SOUTHEAST OF LOCAL AREA OF CONCERN.
BUT THERE MAY BE SOME NUISANCE LIGHT SNOW AT TIMES ACRS THE AREA IN
THE WAKE OF THE MAIN SYSTEM...OR EVEN A SECONDARY WEAK CLIPPER LATE
MONDAY INTO TUE. LONGER RANGE INDICATIONS THEN SUGGEST THE CLIPPER
INDUCING NORTHWESTERLIES WILL EVENTUALLY GIVE WAY TO MILDER UPPER
RIDGING BY MID TO LATE NEXT WEEK...BUT THE TREND HAS BEEN TO DELAY
IT/S ARRIVAL ESPECIALLY IF RE-ENFORCING TROFFINESS ESTABLISHES ACRS
THE WESTERN GRT LKS TUE INTO WED LIKE SOME OF THE LATEST ENSEMBLES
SUGGEST. ..12..
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 538 PM CST THU FEB 11 2016
A FAST MOVING UPPER LEVEL SYSTEM WILL SPREAD LIGHT SNOW ACROSS
CENTRAL AND SOUTHEAST IOWA THIS EVENING. THE GREATEST IMPACT WILL
BE AT BRL...WHERE A PERIOD OF IFR CONDITIONS IS LIKELY THIS
EVENING...PRIMARILY DUE TO LOW VISIBILITIES. FURTHER NORTH...CID
AND MLI WILL LIKELY REMAIN ON THE EDGE OF THIS SYSTEM AND THE
LATEST FORECAST HAS A PERIOD OF MVFR CONDITIONS THIS
EVENING...FOLLOWED BY MVFR CIGS AND FLURRIES THROUGH THE REST OF
THE NIGHT. HAVE ALSO INCLUDED FLURRIES AT DBQ...WITH CIGS LOWERING
TO MVFR LATE TONIGHT THROUGH FRIDAY MORNING. A COLD FRONT DROPPING
SOUTH THROUGH THE AREA FRIDAY WILL BE FOLLOWED BY GUSTY NORTHWEST
WINDS AS HIGH AS 20 TO 30 KTS IN THE AFTERNOON.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...SHEETS
SYNOPSIS...GIBBS
SHORT TERM...GIBBS
LONG TERM...12
AVIATION...SHEETS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
538 PM CST THU FEB 11 2016
...AVIATION UPDATE...
.SYNOPSIS...
ISSUED AT 327 PM CST THU FEB 11 2016
HIGH PRESSURE CENTERED OVER THE EASTERN CWA THIS AFTERNOON AS
LEADING TO CLEAR SKIES AND DRY WEATHER FOR MOST OF THE AREA. A
FAST MOVING CLIPPER IS FORECAST TO AFFECT THE AREA LATER TODAY AND
TONIGHT AND WILL BE THE MAIN FORECAST CONCERN IN THE SHORT TERM
FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 327 PM CST THU FEB 11 2016
MAIN FORECAST CONCERN FOR THE SHORT TERM ARE THE CHANCES FOR SNOW
ASSOCIATED WITH A FAST CLIPPER ACROSS THE AREA TODAY. DRY AIR IN
PLACE WITH THE HIGH OVERHEAD WILL LIMIT OVERALL SNOWFALL TOTALS TO
AROUND AN INCH...WITH LOCALLY HIGHER AMOUNTS JUST OVER AN INCH.
HIRES GUIDANCE IS IN GOOD AGREEMENT THAT THIS WILL START NEAR 00Z
AND BE OUT OF THE AREA BY 08Z.
GUIDANCE TODAY HELD STRONG WITH THE CONSENSUS ON TIMING AND
STRONGEST FORCING WILL REMAIN ACROSS OUR FAR SOUTHERN ZONES. WWD
HAS AROUND AN INCH OF SNOW FOR THIS AREA AND OUR FORECAST
REPRESENTS THIS. LATEST RUNS OF THE HRRR SUGGESTS THAT THE BEST
SNOW WILL BE OUT OF THE AREA BY 06Z WITH LINGERING FLURRIES
THROUGH 09Z ACROSS THE FAR SOUTHERN CWA. WINDS WILL REMAIN LIGHT
SO LITTLE TO NO IMPACTS ARE EXPECTED FROM THIS SNOW. ANY SNOW THAT
ACCUMULATES SHOULD BE DONE BY THE EARLY HOURS.
FRIDAY WILL BE QUIET AND SLIGHTLY WARMER..WITH CLEARING SKIES.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 327 PM CST THU FEB 11 2016
FRIDAY NIGHT...LATEST SUITE OF 12Z RUN MODELS SUGGEST 1045 MB ARCTIC
HIGH PRESSURE STILL ON TRACK TO SURGE DOWN THE UPPER TO MID MS
RIVER VALLEY FRI NIGHT INTO SAT WITH A SCOURING EFFECT. THIS
FEATURE TO COLD DUMP LLVL TEMPS/THICKNESS VALUES TO PRODUCE SUB-
ZERO LOWS ACRS MOST OF THE CWA...BUT SOME CONCERN THAT ONGOING
MIXING SFC WINDS IN INCOMING HIGH PRESSURE GRADIENT TO LIMIT A
COMPLETE BOTTOM OUT. BUT DUE TO BRUTE FORCE COLD AIR
ADVECTION...WILL STILL GO WITH LOWS FROM 5 TO NEAR 10 BELOW ZERO
ACRS THE NORTHWESTERN THIRD OF THE CWA...0 TO 5 BELOW ALONG AND
NORTH OF I80...AND TO THE LOW SINGLE DIGITS ABOVE ZERO IN THE
SOUTHERN CWA. SFC WINDS DECREASING TO 7-10 MPH TOWARD SUNRISE SAT
STILL TO PRODUCE ADVISORY LEVEL WIND CHILLS ACRS AT LEAST THE
NORTHWESTERN THIRD OF THE DVN CWA...AND POSSIBLY ALONG THE HWY 20
CORRIDOR IN NW IL.
SATURDAY AND SUNDAY...THE ARCTIC HIGH OVERHEAD WILL MAKE FOR
TEMPORARY CLEAR AND CALM/LIGHT WIND CONDITIONS FOR FIRST PART OF THE
DAY SAT...WITH HIGH CLOUDS ON THE INCREASE AS THE AFTERNOON
PROGRESSES. THIS AHEAD OF THE ORGANIZING SHORT WAVE UPPER TROF THAT
WILL LOOK TO PROPAGATE TOWARD THE SOUTHWESTERN GRT LKS AND MID MS
RIVER VALLEY ON SUNDAY IN BROADENING WEST-NORTHWESTERLY STEERING
FLOW. THE VARIOUS MEDIUM RANGE SOLUTIONS SUGGEST SOME TYPE OF
ASSOCIATED WARM AIR ADVECTION WING OF SNOW WILL LOOK TO TRY TO GET
INTO THE WESTERN OR SOUTHWESTERN CWA BY EARLY SAT EVENING...BUT
FEEL MODELS MAY BE TOO QUICK WITH THIS TAKING INTO ACCOUNT
STRENGTH OF DRY SFC RIDGE AXIS STILL ON THE MOVE OVER AND EAST OF
THE CWA AT THAT TIME. BUT BY MIDNIGHT SAT NIGHT...BOTH THE 12Z RUN
ECMWF AND GEM SUGGEST SOME LIGHT SNOW ACCUMS STARTING TO TAKE
PLACE ALREADY IN THE FAR SOUTHWESTERN CWA. AGAIN SIDING WITH THE
12Z GEM/ECMWF WHICH ARE IN DECENT AGREEMENT...THE WAA WING OF SNOW
AHEAD OF THE MAIN UPPER TROF WILL LOOK TO CONTINUE TO SPREAD
EASTWARD ACRS MUCH OF THE WESTERN 2/3S OF THE CWA THROUGH 12Z
SUNDAY...BUT MAY GET ERODED SOME AS IT DOES BY ONGOING DRY AIR IN
PLACE AND ALSO SOME IMPACT OF MUCH OF THE INITIAL LIFT GOING INTO
THE TOP-DOWN SATURATION PROCESS. THE LATEST GEM MAY HAVE THE BEST
HANDLE ON THIS IDEA WITH JUST A DUSTING TO HALF INCH WEST OF THE
MS RIVER BY 12Z SUNDAY...BUT WILL GO WITH A FEW TENTHS TO NEAR AN
INCH SOUTHWEST OF A LINE FROM DBQ...TO THE QUAD CITIES...AND TO
MACOMB IN WESTERN IL.
THEN THE MAIN SNOW EVENT WITH THE UPPER TROF WILL LOOK TO OCCUR ON
SUNDAY AND WILL CONTINUE TO ADJUST POPS UP INTO LIKELY OR EVEN
CATEGORICAL. BUT THE 12Z RUN AMERICAN MODELS/ESPECIALLY THE 12Z GFS/
WHICH HINT AT HIGH END ADVISORY OR EVEN LOW END WARNING CRITERIA
AMOUNT SNOWS BY SUNDAY EVENING COMBINING THE TWO SNOW MAKING
PROCESSES...SEEM TOO WET...TOO STRONG LOOKING AT MID AND UPPER LEVEL
JET DYNAMICS MORE FAVORABLE TO THE SOUTH...AND THEIR DEEP SATURATION
IN THE DENDRITIC GROWTH ZONE FOR MUCH OF SUNDAY MORNING INTO EARLY
AFTERNOON. SO CURRENTLY FAVOR A BLEND OF THE 12Z GEM/ECMWF MOISTURE
AND FORCING PROFILES WHICH SUGGEST MOST OF THE CWA TO GET 1-3 OR 2-4
INCHES OF SNOW BY SUNDAY EVENING. INCREASING SOUTH WINDS OF 15-20
MPH MAY PRODUCE SOME DRIFTING TROUBLE BY SUNDAY AFTERNOON AS
WELL...SO THERE MAY BE A NEED FOR AN EVENTUAL ADVISORY EVEN WITH THE
LIGHTER AMOUNTS PRODUCED BY THESE FAVORED SOLUTIONS. STILL 1-3 MORE
MODEL RUNS NEEDED TO FURTHER DEFINE THIS SNOW EVENT FOR MORE
CONFIDENCE.
MONDAY THROUGH NEXT THU...AS THE PASSING TROF CONTINUES TO EVOLVE
ALONG AND EAST OF THE REGION EARLY NEXT WEEK..RESULTANT MAJOR STORM
SHOULD TAKE OFF WELL TO THE EAST/SOUTHEAST OF LOCAL AREA OF CONCERN.
BUT THERE MAY BE SOME NUISANCE LIGHT SNOW AT TIMES ACRS THE AREA IN
THE WAKE OF THE MAIN SYSTEM...OR EVEN A SECONDARY WEAK CLIPPER LATE
MONDAY INTO TUE. LONGER RANGE INDICATIONS THEN SUGGEST THE CLIPPER
INDUCING NORTHWESTERLIES WILL EVENTUALLY GIVE WAY TO MILDER UPPER
RIDGING BY MID TO LATE NEXT WEEK...BUT THE TREND HAS BEEN TO DELAY
IT/S ARRIVAL ESPECIALLY IF RE-ENFORCING TROFFINESS ESTABLISHES ACRS
THE WESTERN GRT LKS TUE INTO WED LIKE SOME OF THE LATEST ENSEMBLES
SUGGEST. ..12..
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 538 PM CST THU FEB 11 2016
A FAST MOVING UPPER LEVEL SYSTEM WILL SPREAD LIGHT SNOW ACROSS
CENTRAL AND SOUTHEAST IOWA THIS EVENING. THE GREATEST IMPACT WILL
BE AT BRL...WHERE A PERIOD OF IFR CONDITIONS IS LIKELY THIS
EVENING...PRIMARILY DUE TO LOW VISIBILITIES. FURTHER NORTH...CID
AND MLI WILL LIKELY REMAIN ON THE EDGE OF THIS SYSTEM AND THE
LATEST FORECAST HAS A PERIOD OF MVFR CONDITIONS THIS
EVENING...FOLLOWED BY MVFR CIGS AND FLURRIES THROUGH THE REST OF
THE NIGHT. HAVE ALSO INCLUDED FLURRIES AT DBQ...WITH CIGS LOWERING
TO MVFR LATE TONIGHT THROUGH FRIDAY MORNING. A COLD FRONT DROPPING
SOUTH THROUGH THE AREA FRIDAY WILL BE FOLLOWED BY GUSTY NORTHWEST
WINDS AS HIGH AS 20 TO 30 KTS IN THE AFTERNOON.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...GIBBS
SHORT TERM...GIBBS
LONG TERM...12
AVIATION...SHEETS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1107 PM CST TUE FEB 9 2016
...AVIATION UPDATE...
.SYNOPSIS...
ISSUED AT 302 PM CST TUE FEB 9 2016
18Z SFC DATA HAS A SEASONABLY STRONG LOW OVER LAKE HURON WITH HIGH
PRESSURE IN THE PLAINS. DEW POINTS WERE IN THE SINGLE DIGITS ABOVE
AND BELOW ZERO ACROSS THE NORTHERN PLAINS AND UPPER MIDWEST. DEW
POINTS IN THE TEENS AND 20S RAN FROM THE GREAT LAKES INTO THE
SOUTHERN PLAINS. RADARS CONTINUE TO SHOW FLURRIES AND SNOW SHOWERS
ACROSS MUCH OF WISCONSIN AND ILLINOIS WITH MORE ISOLATED SNOW
SHOWERS AND FLURRIES IN IOWA.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 302 PM CST TUE FEB 9 2016
BASED ON RADAR AND RAP MODEL TRENDS...THE FLURRIES/SNOW SHOWERS WILL
SLOWLY SHIFT EAST OF THE MISSISSIPPI LATE THIS AFTERNOON WITH A
RATHER RAPID DISSIPATION SHORTLY AFTER SUNSET.
TONIGHT...PARTIAL CLEARING WILL BE SEEN ACROSS MUCH OF THE AREA BUT
THERE WILL BE POCKETS OF CLEAR SKIES BEFORE HIGH LEVEL CLOUDS MOVE
BACK INTO THE AREA. THE PERIOD OF CLEAR SKIES SHOULD ALLOW
TEMPERATURES TO PLUMMET WITH LOWS IN THE SINGLE DIGITS ABOVE/BELOW
ZERO.
WINDS ARE EXPECTED TO REMAIN REASONABLY BRISK DURING THE EVENING
BEFORE SLOWLY DIMINISHING LATE. AS A RESULT...WIND CHILLS WILL DROP
WELL BELOW ZERO TONIGHT. THE EXTREME NORTHWEST CORNER OF THE AREA
MAY SEE WIND CHILLS APPROACH 20 BELOW ZERO PRIOR TO SUNRISE
WEDNESDAY.
QUIET AND COLD CONDITIONS WILL BE SEEN ACROSS THE AREA WEDNESDAY
MORNING AS CLOUDS INCREASE IN ADVANCE OF THE APPROACHING CLIPPER
TYPE SYSTEM. BY MID WEDNESDAY AFTERNOON...AREAS GENERALLY WEST OF A
VINTON IOWA...TO MACOMB ILLINOIS LINE WILL SEE LIGHT SNOW DEVELOP OR
MOVE INTO THE AREA. THE DRY ATMOSPHERE OVER THE AREA MAY INITIALLY
LIMIT ANY SNOW TO FLURRIES BUT LIGHT SNOW SHOULD BE OCCURRING BY
LATE AFTERNOON.
SNOWFALL AMOUNTS BY SUNSET WEDNESDAY ARE EXPECTED TO BE UNDER AN
INCH OF ACCUMULATION.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 302 PM CST TUE FEB 9 2016
MAIN FORECAST CONCERN FOR THE LONG TERM REMAINS TO BE A SERIES OF
CLIPPERS THAT ARE FORECAST TO AFFECT THE AREA ALONG WITH A 1040+
HIGH PRESSURE THIS WEEKEND. SNOWFALL TOTALS LOOK TO BE LIGHT WITH
THESE SYSTEMS...HOWEVER...DUE TO THE NATURE OF THE CLIPPER SYSTEM
EXPECT FORECASTS TO VARY GREATLY LEADING INTO THE EVENT. WIND
CHILLS ON FRIDAY NIGHT STILL APPEAR TO REACH WIND CHILL ADVISORY
LEVELS.
AT THE BEGINNING OF THE PERIOD...A CLIPPER SHOULD BE WELL PAST THE
CWA TO THE SOUTH AND EAST. DETERMINISTIC GRIDDED AND SPECTRAL
MODELS SUGGEST THAT QPF WILL BE OVER FOR MUCH OF THE CWA BY 00Z
THURSDAY. HIRES CAMS KEEP ALL OF THE PRECIP SOUTH OF THE CWA AND
RESULT IN NO SNOW AFTER 00Z THU. AS SUCH...DECIDED TO NOT ADD ANY
QPF OR SNOW ACCUM DURING THIS PERIOD. DECIDED TO ERR ON THE SIDE
OF CAUTION AND INCLUDE A SCHC OF SNOW DURING THIS PERIOD.
THURSDAY APPEARS TO BE A QUIET DAY AS HIGH PRESSURE BEGINS TO BUILD
INTO THE AREA. ANOTHER CLIPPER IS FORECAST TO TRANSVERSE THE REGION
FRIDAY MORNING. THE GEM APPEARS TO SEND THIS CLIPPER WELL INTO THE
CWA WITH COVERAGE ACROSS THE ENTIRE AREA. THIS IS AT ODDS WITH THE
REST OF THE MODELS. AS SUCH...WILL GO WITH SCHC TO CHC POPS AT THIS
TIME. THIS FORECAST WILL LIKELY CHANGE AS MODELS MOVE BACK AND
FORTH. HOWEVER AT THIS TIME...IT LOOKS LIKE MOST OF THE AREA WILL
SEE LESS THAN AN INCH OF SNOW IF THE GEM VERIFIES.
FRIDAY THROUGH EARLY SUNDAY A STRONG 1040+ HIGH MOVES INTO THE AREA.
THIS WILL LEAD TO COLD TEMPERATURES THIS WEEKEND AND A CHANCE FOR
WIND CHILL HEADLINES POSSIBLY FRIDAY NIGHT INTO SATURDAY AM. THE
WEATHER WILL REMAIN QUIET THROUGH SATURDAY.
ON SUNDAY A STRONG WAVE IS FORECAST TO MOVE ACROSS THE N CONUS.
GUIDANCE PREDICTS QPF ACROSS THE AREA. WARMER AIR WILL LIKELY BE
ADVECTED NORTH BY THIS WAVE. AT THIS TIME THERE ARE TOO MANY
DIFFERENCES BETWEEN THE MODELS TO SAY ANYTHING MORE THAN THERE WILL
BE A CHC FOR PRECIP ACROSS THE REGION SUNDAY INTO MONDAY OF NEXT
WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1107 PM CST TUE FEB 9 2016
A PASSING WEAK STORM SYSTEM IN THE NORTHWEST FLOW ALOFT WILL PASS
SOUTHWEST OF THE AREA LATE WEDNESDAY...POSSIBLY SPREADING LIGHT
SNOW INTO SOUTHEAST IA LATE IN THE DAY. THIS MAY AFFECT THE BRL
SITE...WITH A CHANCE FOR VERY LIGHT SNOW OR SNOW FLURRIES FROM
MID AFTERNOON INTO EARLY EVENING IN THE LATEST FORECAST.
OTHERWISE...VFR CONDITIONS WILL BE THE RULE WITH LIGHT NORTH TO
NORTHWEST WINDS AND INCREASING MID AND HIGH LEVEL CLOUD COVER AS
THE SYSTEM APPROACHES.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...08
SHORT TERM...08
LONG TERM...GIBBS
AVIATION...SHEETS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
841 PM EST THU FEB 11 2016
.UPDATE...
ISSUED AT 830 PM EST THU FEB 11 2016
HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS.
TIMING OF THE ONSET OF SNOW AND ASSOCIATED POPS HAS BEEN FRESHENED
UP LATE TONIGHT AND EARLY ON FRI BASED ON RECENT MODEL TRENDS.
18Z AND RECENT HRRR RUNS GENERALLY KEEP THE HIGHEST QPF AND BEST
CHANCES FOR MEASURABLE SNOW SOUTH OF THE HAL ROGERS PARKWAY AND KY
80 CORRIDOR. IN THIS AREA...AROUND AN INCH IS ANTICIPATED THROUGH
NOON ON FRIDAY. FURTHER NORTH...LESSER AMOUNTS ARE ANTICIPATED.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 255 PM EST THU FEB 11 2016
19Z SFC ANALYSIS SHOWS AN AREA OF HIGH PRESSURE SLIPPING INTO THE
OHIO VALLEY. TO THE SOUTH AND WEST OF THIS...LOW PRESSURE IS
STARTING TO DEVELOP. ON SATELLITE...SOME LOWER AND MID LEVEL
CLOUDS ARE CLEARING OUT OF THE AREA WHILE THE NEXT ROUND OF
CLOUDS ARE HEADING TOWARD THE AREA FROM THE NORTHWEST. THE PARTIAL
SUNSHINE OF TODAY HELPED TEMPERATURES TO REBOUND INTO THE MID AND
UPPER 20S NORTH AND UPPER 20S TO LOWER 30S IN THE SOUTH.
DEWPOINTS...MEANWHILE...ARE RUNNING IN THE 10 TO 15 DEGREE RANGE
WITH LIGHT WINDS...GENERALLY FROM THE NORTHWEST.
THE MODELS ARE IN GREAT AGREEMENT ALOFT WITH THE EASTERN TROUGH
RETREATING TO THE NORTH TONIGHT. IN THE NORTHWEST FLOW THAT
FOLLOWS FOR KENTUCKY A QUICK HITTING SHORTWAVE WILL PUNCH THROUGH
THE TENNESSEE VALLEY FRIDAY MORNING. THE CORE OF THIS WILL MAINLY
PASS WEST OF EASTERN KENTUCKY...BUT ALSO BRING SOME HEIGHT FALLS
TO THE AREA FOR THE DAY. ANOTHER SHARP TROUGH TO THE NORTH WILL
SWING THROUGH THE GREAT LAKES LATER FRIDAY INTO SATURDAY MORNING
WITH ADDITIONAL STREAMS OF ENERGY BRUSHING THE NORTHEAST PORTION
OF THE STATE. GIVEN THE MODEL AGREEMENT WILL FAVOR A GENERAL
BLEND ALONG WITH A LEAN TOWARD THE HIGHER RESOLUTION NAM12 AND
HRRR.
SENSIBLE WEATHER WILL FEATURE A QUIET AND CHILLY EVENING WITH
LIGHT SNOW DEVELOPING TOWARD DAWN IN THE WEST AND SHORTLY AFTER IN
THE EAST. THE CLIPPER SYSTEM BRINGING THE SNOW WILL TARGET THE
SOUTHERN PORTION OF THE AREA FRIDAY MORNING WITH AROUND AN INCH OF
SNOW EXPECTED. THE SNOW SHOULD TAPER OFF BY NOON FOR MOST OF
EASTERN KENTUCKY...BUT COULD LINGER IN THE FAR NORTHEAST.
ADDITIONAL SNOW SHOWERS WILL BE POSSIBLE IN THE EVENING AND
OVERNIGHT INTO SATURDAY MORNING...WITH ACCUMULATIONS MAINLY
CONFINED TO THE FAR EASTERN PARTS OF THE AREA DUE TO UPSLOPE
FLOW. THIS FIRST BATCH OF SNOW WILL BE ROBUST FOR A FEW HOURS
DURING THE MORNING AND RIGHT THROUGH THE MORNING COMMUTE HOURS.
ON ACCOUNT OF THIS...AND AS IT TARGETS SOME OF THE MAIN
THOROUGHFARES IN OUR CWA...HAVE ISSUED AN ADVISORY FOR OUR
SOUTHERN TIER OVER TO PIKE COUNTY FROM 10Z THROUGH 17Z. AN SPS
WILL BE ISSUED FOR THE REMAINDER OF THE AREA FOR LATE TONIGHT
INTO FRIDAY MORNING. AN ADDITIONAL SPS OR ADVISORY MAY BE NEEDED
FOR LATER FRIDAY INTO EARLY SATURDAY FOR OUR UPSLOPE AREAS. WILL
DETAIL ALL THIS IN THE HWO...AS WELL.
AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR THE T/TD/WIND
GRIDS THROUGH THE NIGHT BEFORE FAVORING THE SUPERBLEND THEREAFTER.
ONLY MADE SOME MINOR ADJUSTMENTS TO THE TEMPS TONIGHT AND FRIDAY
NIGHT DUE TO TERRAIN DIFFERENCES BOTH NIGHTS. AS FOR POPS...WENT
ON THE HIGH SIDE OF MOS GUIDANCE THROUGH THE PERIOD...GENERALLY IN
LINE WITH THE MET TONIGHT/FRIDAY AND MUCH ABOVE FRIDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 359 PM EST THU FEB 11 2016
...ANOTHER WINTER STORM ON TAP FOR EARLY NEXT WEEK...
ARCTIC AIR WILL BE ENTRENCHED OVER THE AREA BY SATURDAY...SETTING
UP A VERY COLD DAY WHERE WE WILL LIKELY EXCEED OUR COLDEST HIGH
TEMPERATURES ON RECORD FOR THE DATE. HIGHS WILL STRUGGLE TO REACH
THE MID TO UPPER TEENS. GIVEN THE COLD AIRMASS AND CONTINUED
NORTHWEST FLOW...SOME FLURRIES/SNOW SHOWERS WILL REMAIN POSSIBLE
THROUGH THE DAY AND EVEN INTO THE EVENING...BUT SHOULD NOT POSE
MUCH OF AN IMPACT TO THE AREA. A COLD NIGHT WILL BE SEEN SATURDAY
NIGHT...WITH SOME RECOVERY IN TEMPERATURES EXPECTED ON SUNDAY.
HOWEVER...MID/HIGH CLOUDS WILL INCREASE AND WE COULD START SEEING
SOME FLURRIES/LIGHT SNOW SHOWERS DURING THE DAY SUNDAY. BY SUNDAY
NIGHT...A WARM FRONT WILL PUSH NORTH ACROSS THE AREA WITH LIGHT
SNOW BREAKING OUT ACROSS THE REGION. THIS LOOKS LIKE IT COULD
PRODUCE A LIGHT COATING OF SNOW ACROSS MOST OF THE AREA INTO EARLY
MONDAY MORNING.
THIS BRINGS US INTO EARLY NEXT WEEK...WHERE CONFIDENCE REMAINS
SOMEWHAT LOW AS MODELS ARE STILL SORTING OUT ALL THE DIFFERENCES.
12Z GFS/ECMWF HAVE TRENDED TOWARD A MORE NORTHERN TRACK OF THE
LOW...WITH MILDER CONDITIONS SPREADING INTO EASTERN KENTUCKY. THIS
MAY SUPPORT A CHANGEOVER TO RAIN ON MONDAY...OR FREEZING RAIN IF
TEMPERATURES IN THE VALLEYS DON`T RECOVER FAST ENOUGH.
HOWEVER...THE TRACK OF THE SYSTEM WILL DETERMINE EXACTLY WHERE
SNOW/FREEZING RAIN/RAIN FALLS...SO UNTIL MODELS COME INTO
AGREEMENT...TRYING TO PIN DOWN DETAILS WILL BE VERY DIFFICULT.
REGARDLESS...THOSE WITH PLANS EARLY NEXT WEEK SHOULD STAY AWARE OF
THE POTENTIAL FOR A WINTER STORM IN THE COMING DAYS AND CHECK BACK
WITH THE FORECAST. AS THIS SYSTEM DEPARTS BY TUESDAY...IT LOOKS
LIKE A WEAK TROUGH DEVELOPS OVER THE AREA AGAIN WITH POTENTIAL
RAIN/SNOW SHOWERS LINGERING INTO MIDWEEK. BY THE END OF THE
WEEK...THE TROUGH EXITS WITH STRONG RIDGING BUILDING BACK INTO THE
AREA. THIS WILL YIELD A MORE SIGNIFICANT WARM UP BY THE END OF
NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 735 PM EST THU FEB 11 2016
MVFR SHOULD PREVAIL THROUGH AT LEAST THE FIRST 9 TO 12Z HOURS OF
THE PERIOD. HOWEVER...CIGS SHOULD THEN LOWER INTO THE MVFR RANGE
TOWARD DAWN AS A CLIPPER SYSTEM BRINGS SOME SNOW TO THE AREA. THIS
SHOULD AFFECT THE FOUR SOUTHERNMOST OF THE TAF SITES. THE BEST
CHANCES FOR LOW VIS AND CIGS WILL BE THROUGH THE SOUTHERN HALF OF
THE CWA PEAKING IN THE 12Z TO 16Z RANGE. WINDS WILL BE RELATIVELY
LIGHT AT 5 TO 10 KT DURING THE PERIOD...GENERALLY FROM THE WEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 5 AM TO NOON EST FRIDAY FOR KYZ068-
069-079-080-083>088-110-112>118-120.
&&
$$
UPDATE...JP
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...JP
AREA FORECAST DISCUSSION
NWS GRAY ME
1115 AM EST WED FEB 10 2016
.SYNOPSIS...
THE REGION REMAINS UNDER WEAK LOW PRESSURE TODAY. THIS WILL BE THE
FOCUS FOR SNOW SHOWERS...WHICH WILL BRING LIGHT ACCUMULATIONS
GENERALLY BUT UP TO SEVERAL INCHES IN THE MOUNTAINS. CLOUDY
WEATHER LINGERS TONIGHT...AHEAD OF AN APPROACHING COLD FRONT SET
TO CROSS THE AREA THURSDAY. SNOW SHOWERS WILL BE LIKELY ALONG AND
AHEAD OF THAT FRONT...BEFORE COLDER AIR ARRIVES. WE HAVE A BRIEF
BREAK IN STORE FRIDAY...BUT THEN A STRONG COLD FRONT DRIVES
THROUGH THE REGION AND THE COLDEST AIR OF THE SEASON SETTLES IN
FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
1055 AM...THIS UPDATE BACKS OFF QPF AND SUBSEQUENT SNOW AMOUNT A
LITTLE BIT FOR THIS AFTERNOON AND ADJUSTS POPS A BIT FOR THE REST
OF TODAY BASED ON CURRENT OB. SNOW IS LIGHT AND RADAR NOT DOING A
GOOD JOB OF PICKING UP THIS MORNING...BUT IT CONTINUES TO SNOW
ACROSS SRN AND CENTRAL NH...ALBEIT VERY LIGHTLY. EXPECTING THIS
SNOW ILL CONTINUE INTO EARLY TO MID AFTERNOON BEFORE ENDING...AND
MAY SEE ACCUMS UP TO AN INCH...ESPECIALLY AS YOU HEAD INTO THE
LAKES REGION AND THE WHITE MTNS. MESO MODELS DO BACK OFF THE
POPS/QPF FOR THIS AFTERNOON AS THIS WEAK WAVE ALOFT MOVES INTO
MAINE...BUT SHOULD SEE AT LEAST SOME SHN...IF A PERIOD OF LIGHT
SNOW HERE BY MI-LATE AFTERNOON.
UPDATE...MINOR CHANGES FOR POP AND TEMPS AS SNWFL EDGES CLOSER TO
THE FORECAST AREA. A FEW POCKETS OF SN SHOWERS HAVE INTERMITTENTLY
CROSSED PARTS OF NH SO FAR...BUT ABOUT AN HOUR OR SO TO THE W THE
MORE CONCENTRATED LIFT IS PRODUCING AN AREA OF LIGHT SN THRU THE
HUDSON VALLEY. THAT WILL OVERSPREAD SWRN NH THRU THE SEACOAST THRU
MORNING.
PREVIOUS DISCUSSION...NEW ENGLAND REMAINS ON THE DOWNSTREAM SIDE
OF A SLOWLY ADVANCING UPPER TROF. THIS FAVORABLY PLACES THE AREA
ON THE WAA SIDE...AND COUPLED WITH ANY S/WV TROF ROTATING THRU THE
LARGER FLOW...WX WILL REMAIN UNSETTLED.
ONE SUCH STRONGER S/WV TROF WILL MOVE THRU THE ERN GREAT LAKES
TODAY. THIS WILL ENHANCE SLY FLOW INTO THE AREA...AND DEVELOP A
WEAK SFC TROF IN THE REGION. THIS PROVIDES A FOCUS FOR SN SHOWERS
THRU TODAY. HI-RES GUIDANCE SUGGEST THIS IS MOST LIKELY ACROSS NH
FOR THE EARLY PART OF THE DAY. REGIONAL RADAR STARTING TO SHOW
ECHOES DEVELOPING TO THE SW...LENDING SOME CREDIBILITY TO THOSE
SOLUTIONS. QPF WILL BE LIGHT...BUT AROUND AN INCH OF ACCUMULATION
IS POSSIBLE THRU NOON FOR NH. ACTIVITY SHIFTS EWD IN THE
AFTERNOON...AND MOST LIKELY AREA FOR SN SHOWERS SHIFTS TO COASTAL
WRN ME. WILL HAVE TO KEEP AN EYE ON WRN ZONES AGAIN LATER
TODAY...AS LATEST HRRR RUNS DEVELOP BANDS OF SN SHOWERS THAT MOVE
OFF THE GREAT LAKES AS CAA PICKS UP.
&&
.SHORT TERM /THURSDAY/...
FEEL THAT WE TAKE A BRIEF BREAK TONIGHT WITH THE PRECIP.
HOWEVER...LINGERING LOW LEVEL MOISTURE AND WEAK LIFT
ALOFT...CANNOT RULE OUT A STRAY SN SHOWER. POP GENERALLY STAYS
AROUND SLIGHT CHANCE FOR THE AREA. ALSO EXPECT TO SEE SIMILAR
CONDITIONS TO TONIGHT. WITH GENERAL CLOUD COVER...BUT SOME BREAKS
DEVELOPING. THOSE AREAS WILL BE ABLE TO QUICKLY COOL OFF...BUT
TOUGH TO IDENTIFY OUTSIDE OF A COUPLE HOURS BEFORE.
UPPER TROF AXIS IS SET TO CROSS THE AREA THU. EXPECT MORE SN
SHOWERS TO FORM ALONG AND AHEAD OF IT. LATE IN THE DAY STRONG CAA
LOOKS LIKELY. IN ADDITION TO FALLING TEMPS...WINDS WILL BECOME
GUSTY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
A NARROW RIDGE OF HIGH PRESSURE WILL BUILD IN FROM THE WEST THURSDAY
NIGHT BRINGING A BRIEF PERIOD OF CLEARING SKIES AND
DIMINISHING WINDS. THIS WILL ALLOW TEMPERATURES TO PLUMMET AFTER
MIDNIGHT BOTTOMING OUT AT 5 BELOW TO NEAR ZERO NORTH AND RANGING
THROUGH THE SINGLE NUMBERS SOUTH.
NEXT IN A SERIES OF WEAK MOISTURE STARVED CLIPPER SYSTEMS WILL
GRADUALLY PUSH IN FROM THE WEST ON FRIDAY. THIS WILL BRING INCREASING
CLOUDS IN THE AFTERNOON AND A CHANCE OF SNOW SHOWERS IN NORTHWEST
ZONES BY LATE IN THE DAY. HIGH TEMPS WILL AVERAGE OUTWELL BELOW
NORMAL WITH READINGS ONLY REACHING 5 TO 15 NORTH AND MID TEENS TO
MID 20S SOUTH.
WEAK SURFACE LOW WILL CROSS NORTHERN NEW ENGLAND FRIDAY NIGHT
DRIVING AN ARCTIC FRONT THROUGH THE REGION BY SATURDAY MORNING.
EXPECT SNOW SHOWERS AND SQUALLS OVERNIGHT WITH SEVERAL INCHES OF
ACCUMULATION POSSIBLE IN THE MOUNTAINS AND FOOTHILLS. LOW
TEMPERATURES WILL DIP TO 5 BELOW TO 5 ABOVE NORTH AND 5 TO 10
DEGREES SOUTH.
STRONG NORTHWEST FLOW WILL KICK IN BEHIND DEPARTING LOW PRESSURE ON
SATURDAY USHERING IN SOME OF THE COLDEST AIR OF THE SEASON.
DEEP UPPER LOW SETTLING INTO THE NORTHEAST WILL KEEP CLOUDS AND
SNOW SHOWERS IN THE FORECAST THROUGH THE DAY. ONCE AGAIN UPSLOPE
AREAS IN THE MOUNTAINS WILL LIKELY SEE SOME ADDITIONAL MINOR
ACCUMULATIONS. HIGH TEMPS WILL RANGE THROUGH THE SINGLE NUMBERS
NORTH AND TEENS SOUTH.
UPPER LOW WILL SHIFT EAST SATURDAY NIGHT BUT INTENSE NORTHWEST FLOW
WILL CONTINUE ACROSS THE REGION AS SURFACE HIGH PRESSURE BEGINS
TO BUILD IN FROM THE WEST. SHOULD SEE SNOW SHOWER ACTIVITY
DIMINISH OVERNIGHT WITH AT LEAST PARTIAL CLEARING AFTER MIDNIGHT.
DESPITE THE WINDS EXPECT LOW TEMPS TO DIP TO 10 TO 15 BELOW NORTH
AND 5 TO 10 BELOW SOUTH. THIS IN COMBINATION WITH THE STRONG
WINDS WILL RESULT IN DANGEROUS WIND CHILLS OVERNIGHT AND WILL
LIKELY EXCEED WIND CHILL WARNING CRITERIA ACROSS A GOOD PORTION
OF THE FORECAST AREA.
WINDS WILL SLOWLY DIMINISH ON SUNDAY AS HIGH PRESSURE CONTINUES TO
BUILD IN FROM THE WEST. LOOKING FOR A MIX OF SUN AND CLOUDS IN
THE SOUTH WITH MOUNTAIN CLOUDS GRADUALLY CLEARING DURING THE
AFTERNOON. HIGH TEMPS WILL ONLY RANGE THROUGH THE SINGLE NUMBERS
NORTH AND LOWER TO MID TEENS SOUTH.
HIGH PRESSURE WILL CREST OVER THE REGION SUNDAY NIGHT. SHOULD SEE
ANOTHER VERY COLD NIGHT WITH LOWS OF 5 TO 10 BELOW NORTH AND 5 BELOW
TO 5 ABOVE SOUTH.
NEXT SHORTWAVE WILL PUSH HIGH CLOUDS INTO THE REGION BEFORE DAYBREAK
ON MONDAY AS A BROAD AREA OF OVER-RUNNING PUSHES IN FROM THE
WEST. HIGH PRESSURE WILL SHIFT OFFSHORE MONDAY MORNING AND CLOUDS
WILL LOWER AND THICKEN MONDAY AFTERNOON AS LIGHT SNOW OR SNOW
SHOWERS PUSH IN FROM THE WEST. EXPECT SOME MINOR ACCUMULATIONS BY
LATE IN THE DAY AND INTO MONDAY EVENING...BUT NOT LOOKING LIKE A
BIG DEAL AT THIS POINT IN TIME.
MORE SUBSTANTIAL SYSTEM MAY BE ON TAP FOR TUESDAY AS SHORTWAVE
HITS THE EAST COAST AND SPINS UP A COASTAL LOW BUT MODELS SHOWING
SOME BIG DIFFS IN TRACK AND TIMING WITH THIS FEATURE.
&&
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM...FORECAST AREA REMAINS IN CONTROL OF A BROAD UPPER
TROF. THIS IS KEEPING THE WX A LITTLE UNSETTLED...AND WILL
CONTINUE TO DO SO THRU THU. AREAS OF MVFR CIGS ARE SLOWLY MOVING
INTO AND THRU THE AREA...AND WILL BE MOST LIKELY ACROSS NH THE
FIRST PART OF TODAY. WRN ME WILL SEE MVFR CIGS ADVANCE INTO THOSE
ZONES BY THE AFTERNOON. WITHIN THE SFC TROF...SNWFL WILL BE
POSSIBLE...WITH AREAS OF IFR. CONFIDENCE IS LOW ON EXACTLY WHERE
AND HOW LONG IFR CONDITIONS LAST...BUT AGAIN MOST LIKELY AREAS ARE
ACROSS NH TERMINALS. TROF AXIS CROSSES THE AREA THU...WITH SHSN
LIKELY TO FORM AGAIN.
LONG TERM...AREAS MVFR CEILINGS THURSDAY EVENING...BECOMING VFR.
VFR FRIDAY WITH AREAS OF MVFR CEILINGS IN THE MOUNTAINS FRIDAY
AFTERNOON. AREAS OF MVFR CEILINGS/VSBY FRIDAY NIGHT AND SATURDAY.
VFR ON SUNDAY.
&&
.MARINE...
SHORT TERM...HIGH SEAS ARE GRADUALLY TRANSITIONING TO LONG PERIOD
SWELL. WITH SOME WAVE HEIGHTS STILL OVER 7 FT...WILL CONTINUE THE
SCA FOR HAZARDOUS SEAS THRU MORNING. AS COLD FNT CROSSES THE
WATERS LATE THU...A BRIEF PERIOD OF GALE FORCE WIND GUSTS IS
POSSIBLE. RIGHT NOW MOST LIKELY AREAS ARE S OF CAPE
ELIZABETH...AND A GALE WATCH HAS BEEN ISSUED.
LONG TERM...GALES LIKELY SATURDAY INTO SUNDAY.
&&
.COASTAL FLOODING...
VERY MINOR COASTAL FLOODING MAY OCCUR NEAR THE NOONTIME HIGH TIDE.
AN ADVISORY HAS BEEN ISSUED FOR THIS LOW END EVENT.
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...COASTAL FLOOD ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MEZ023-024.
NH...COASTAL FLOOD ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
NHZ014.
MARINE...GALE WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING
FOR ANZ154.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAY ME
1108 AM EST WED FEB 10 2016
.SYNOPSIS...
THE REGION REMAINS UNDER WEAK LOW PRESSURE TODAY. THIS WILL BE THE
FOCUS FOR SNOW SHOWERS...WHICH WILL BRING LIGHT ACCUMULATIONS
GENERALLY BUT UP TO SEVERAL INCHES IN THE MOUNTAINS. CLOUDY
WEATHER LINGERS TONIGHT...AHEAD OF AN APPROACHING COLD FRONT SET
TO CROSS THE AREA THURSDAY. SNOW SHOWERS WILL BE LIKELY ALONG AND
AHEAD OF THAT FRONT...BEFORE COLDER AIR ARRIVES. WE HAVE A BRIEF
BREAK IN STORE FRIDAY...BUT THEN A STRONG COLD FRONT DRIVES
THROUGH THE REGION AND THE COLDEST AIR OF THE SEASON SETTLES IN
FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
1055 AM...THIS UPDATE BACKS OFF QPF AND SUBSEQUENT SNOW AMOUNT A
LITTLE BIT FOR THIS AFTERNOON AND ADJUSTS POPS A BIT FOR THE REST
OF TODAY BASED ON CURRENT OB. SNOW IS LIGHT AND RADAR NOT DOING A
GOOD JOB OF PICKING UP THIS MORNING...BUT IT CONTINUES TO SNOW
ACROSS SRN AND CENTRAL NH...ALBEIT VERY LIGHTLY. EXPECTING THIS
SNOW ILL CONTINUE INTO EARLY TO MID AFTERNOON BEFORE ENDING...AND
MAY SEE ACCUMS UP TO AN INCH...ESPECIALLY AS YOU HEAD INTO THE
LAKES REGION AND THE WHITE MTNS. MESO MODELS DO BACK OFF THE
POPS/QPF FOR THIS AFTERNOON AS THIS WEAK WAVE ALOFT MOVES INTO
MAINE...BUT SHOULD SEE AT LEAST SOME SHN...IF A PERIOD OF LIGHT
SNOW HERE BY MI-LATE AFTERNOON.
UPDATE...MINOR CHANGES FOR POP AND TEMPS AS SNWFL EDGES CLOSER TO
THE FORECAST AREA. A FEW POCKETS OF SN SHOWERS HAVE INTERMITTENTLY
CROSSED PARTS OF NH SO FAR...BUT ABOUT AN HOUR OR SO TO THE W THE
MORE CONCENTRATED LIFT IS PRODUCING AN AREA OF LIGHT SN THRU THE
HUDSON VALLEY. THAT WILL OVERSPREAD SWRN NH THRU THE SEACOAST THRU
MORNING.
PREVIOUS DISCUSSION...NEW ENGLAND REMAINS ON THE DOWNSTREAM SIDE
OF A SLOWLY ADVANCING UPPER TROF. THIS FAVORABLY PLACES THE AREA
ON THE WAA SIDE...AND COUPLED WITH ANY S/WV TROF ROTATING THRU THE
LARGER FLOW...WX WILL REMAIN UNSETTLED.
ONE SUCH STRONGER S/WV TROF WILL MOVE THRU THE ERN GREAT LAKES
TODAY. THIS WILL ENHANCE SLY FLOW INTO THE AREA...AND DEVELOP A
WEAK SFC TROF IN THE REGION. THIS PROVIDES A FOCUS FOR SN SHOWERS
THRU TODAY. HI-RES GUIDANCE SUGGEST THIS IS MOST LIKELY ACROSS NH
FOR THE EARLY PART OF THE DAY. REGIONAL RADAR STARTING TO SHOW
ECHOES DEVELOPING TO THE SW...LENDING SOME CREDIBILITY TO THOSE
SOLUTIONS. QPF WILL BE LIGHT...BUT AROUND AN INCH OF ACCUMULATION
IS POSSIBLE THRU NOON FOR NH. ACTIVITY SHIFTS EWD IN THE
AFTERNOON...AND MOST LIKELY AREA FOR SN SHOWERS SHIFTS TO COASTAL
WRN ME. WILL HAVE TO KEEP AN EYE ON WRN ZONES AGAIN LATER
TODAY...AS LATEST HRRR RUNS DEVELOP BANDS OF SN SHOWERS THAT MOVE
OFF THE GREAT LAKES AS CAA PICKS UP.
&&
.SHORT TERM /THURSDAY/...
FEEL THAT WE TAKE A BRIEF BREAK TONIGHT WITH THE PRECIP.
HOWEVER...LINGERING LOW LEVEL MOISTURE AND WEAK LIFT
ALOFT...CANNOT RULE OUT A STRAY SN SHOWER. POP GENERALLY STAYS
AROUND SLIGHT CHANCE FOR THE AREA. ALSO EXPECT TO SEE SIMILAR
CONDITIONS TO TONIGHT. WITH GENERAL CLOUD COVER...BUT SOME BREAKS
DEVELOPING. THOSE AREAS WILL BE ABLE TO QUICKLY COOL OFF...BUT
TOUGH TO IDENTIFY OUTSIDE OF A COUPLE HOURS BEFORE.
UPPER TROF AXIS IS SET TO CROSS THE AREA THU. EXPECT MORE SN
SHOWERS TO FORM ALONG AND AHEAD OF IT. LATE IN THE DAY STRONG CAA
LOOKS LIKELY. IN ADDITION TO FALLING TEMPS...WINDS WILL BECOME
GUSTY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
A NARROW RIDGE OF HIGH PRESSURE WILL BUILD IN FROM THE WEST THURSDAY
NIGHT BRINGING A BRIEF PERIOD OF CLEARING SKIES AND
DIMINISHING WINDS. THIS WILL ALLOW TEMPERATURES TO PLUMMET AFTER
MIDNIGHT BOTTOMING OUT AT 5 BELOW TO NEAR ZERO NORTH AND RANGING
THROUGH THE SINGLE NUMBERS SOUTH.
NEXT IN A SERIES OF WEAK MOISTURE STARVED CLIPPER SYSTEMS WILL
GRADUALLY PUSH IN FROM THE WEST ON FRIDAY. THIS WILL BRING INCREASING
CLOUDS IN THE AFTERNOON AND A CHANCE OF SNOW SHOWERS IN NORTHWEST
ZONES BY LATE IN THE DAY. HIGH TEMPS WILL AVERAGE OUTWELL BELOW
NORMAL WITH READINGS ONLY REACHING 5 TO 15 NORTH AND MID TEENS TO
MID 20S SOUTH.
WEAK SURFACE LOW WILL CROSS NORTHERN NEW ENGLAND FRIDAY NIGHT
DRIVING AN ARCTIC FRONT THROUGH THE REGION BY SATURDAY MORNING.
EXPECT SNOW SHOWERS AND SQUALLS OVERNIGHT WITH SEVERAL INCHES OF
ACCUMULATION POSSIBLE IN THE MOUNTAINS AND FOOTHILLS. LOW
TEMPERATURES WILL DIP TO 5 BELOW TO 5 ABOVE NORTH AND 5 TO 10
DEGREES SOUTH.
STRONG NORTHWEST FLOW WILL KICK IN BEHIND DEPARTING LOW PRESSURE ON
SATURDAY USHERING IN SOME OF THE COLDEST AIR OF THE SEASON.
DEEP UPPER LOW SETTLING INTO THE NORTHEAST WILL KEEP CLOUDS AND
SNOW SHOWERS IN THE FORECAST THROUGH THE DAY. ONCE AGAIN UPSLOPE
AREAS IN THE MOUNTAINS WILL LIKELY SEE SOME ADDITIONAL MINOR
ACCUMULATIONS. HIGH TEMPS WILL RANGE THROUGH THE SINGLE NUMBERS
NORTH AND TEENS SOUTH.
UPPER LOW WILL SHIFT EAST SATURDAY NIGHT BUT INTENSE NORTHWEST FLOW
WILL CONTINUE ACROSS THE REGION AS SURFACE HIGH PRESSURE BEGINS
TO BUILD IN FROM THE WEST. SHOULD SEE SNOW SHOWER ACTIVITY
DIMINISH OVERNIGHT WITH AT LEAST PARTIAL CLEARING AFTER MIDNIGHT.
DESPITE THE WINDS EXPECT LOW TEMPS TO DIP TO 10 TO 15 BELOW NORTH
AND 5 TO 10 BELOW SOUTH. THIS IN COMBINATION WITH THE STRONG
WINDS WILL RESULT IN DANGEROUS WIND CHILLS OVERNIGHT AND WILL
LIKELY EXCEED WIND CHILL WARNING CRITERIA ACROSS A GOOD PORTION
OF THE FORECAST AREA.
WINDS WILL SLOWLY DIMINISH ON SUNDAY AS HIGH PRESSURE CONTINUES TO
BUILD IN FROM THE WEST. LOOKING FOR A MIX OF SUN AND CLOUDS IN
THE SOUTH WITH MOUNTAIN CLOUDS GRADUALLY CLEARING DURING THE
AFTERNOON. HIGH TEMPS WILL ONLY RANGE THROUGH THE SINGLE NUMBERS
NORTH AND LOWER TO MID TEENS SOUTH.
HIGH PRESSURE WILL CREST OVER THE REGION SUNDAY NIGHT. SHOULD SEE
ANOTHER VERY COLD NIGHT WITH LOWS OF 5 TO 10 BELOW NORTH AND 5 BELOW
TO 5 ABOVE SOUTH.
NEXT SHORTWAVE WILL PUSH HIGH CLOUDS INTO THE REGION BEFORE DAYBREAK
ON MONDAY AS A BROAD AREA OF OVER-RUNNING PUSHES IN FROM THE
WEST. HIGH PRESSURE WILL SHIFT OFFSHORE MONDAY MORNING AND CLOUDS
WILL LOWER AND THICKEN MONDAY AFTERNOON AS LIGHT SNOW OR SNOW
SHOWERS PUSH IN FROM THE WEST. EXPECT SOME MINOR ACCUMULATIONS BY
LATE IN THE DAY AND INTO MONDAY EVENING...BUT NOT LOOKING LIKE A
BIG DEAL AT THIS POINT IN TIME.
MORE SUBSTANTIAL SYSTEM MAY BE ON TAP FOR TUESDAY AS SHORTWAVE
HITS THE EAST COAST AND SPINS UP A COASTAL LOW BUT MODELS SHOWING
SOME BIG DIFFS IN TRACK AND TIMING WITH THIS FEATURE.
&&
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM...FORECAST AREA REMAINS IN CONTROL OF A BROAD UPPER
TROF. THIS IS KEEPING THE WX A LITTLE UNSETTLED...AND WILL
CONTINUE TO DO SO THRU THU. AREAS OF MVFR CIGS ARE SLOWLY MOVING
INTO AND THRU THE AREA...AND WILL BE MOST LIKELY ACROSS NH THE
FIRST PART OF TODAY. WRN ME WILL SEE MVFR CIGS ADVANCE INTO THOSE
ZONES BY THE AFTERNOON. WITHIN THE SFC TROF...SNWFL WILL BE
POSSIBLE...WITH AREAS OF IFR. CONFIDENCE IS LOW ON EXACTLY WHERE
AND HOW LONG IFR CONDITIONS LAST...BUT AGAIN MOST LIKELY AREAS ARE
ACROSS NH TERMINALS. TROF AXIS CROSSES THE AREA THU...WITH SHSN
LIKELY TO FORM AGAIN.
LONG TERM...AREAS MVFR CEILINGS THURSDAY EVENING...BECOMING VFR.
VFR FRIDAY WITH AREAS OF MVFR CEILINGS IN THE MOUNTAINS FRIDAY
AFTERNOON. AREAS OF MVFR CEILINGS/VSBY FRIDAY NIGHT AND SATURDAY.
VFR ON SUNDAY.
&&
.MARINE...
SHORT TERM...HIGH SEAS ARE GRADUALLY TRANSITIONING TO LONG PERIOD
SWELL. WITH SOME WAVE HEIGHTS STILL OVER 7 FT...WILL CONTINUE THE
SCA FOR HAZARDOUS SEAS THRU MORNING. AS COLD FNT CROSSES THE
WATERS LATE THU...A BRIEF PERIOD OF GALE FORCE WIND GUSTS IS
POSSIBLE. RIGHT NOW MOST LIKELY AREAS ARE S OF CAPE
ELIZABETH...AND A GALE WATCH HAS BEEN ISSUED.
LONG TERM...GALES LIKELY SATURDAY INTO SUNDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 AM EST THIS
MORNING FOR ANZ150-152-154.
GALE WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING
FOR ANZ154.
&&
$$
SYNOPSIS...
NEAR TERM...CEMPA/LEGRO
SHORT TERM...LEGRO
LONG TERM...SINSABAUGH
AVIATION...LEGRO/SINSABAUGH
MARINE...LEGRO/SINSABAUGH
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
545 AM EST WED FEB 10 2016
.SYNOPSIS...
THE REGION REMAINS UNDER WEAK LOW PRESSURE TODAY. THIS WILL BE THE
FOCUS FOR SNOW SHOWERS...WHICH WILL BRING LIGHT ACCUMULATIONS
GENERALLY BUT UP TO SEVERAL INCHES IN THE MOUNTAINS. CLOUDY
WEATHER LINGERS TONIGHT...AHEAD OF AN APPROACHING COLD FRONT SET
TO CROSS THE AREA THURSDAY. SNOW SHOWERS WILL BE LIKELY ALONG AND
AHEAD OF THAT FRONT...BEFORE COLDER AIR ARRIVES. WE HAVE A BRIEF
BREAK IN STORE FRIDAY...BUT THEN A STRONG COLD FRONT DRIVES
THROUGH THE REGION AND THE COLDEST AIR OF THE SEASON SETTLES IN
FOR THE WEEKEND.
&&
.NEAR TERM /TODAY/...
UPDATE...MINOR CHANGES FOR POP AND TEMPS AS SNWFL EDGES CLOSER TO
THE FORECAST AREA. A FEW POCKETS OF SN SHOWERS HAVE INTERMITTENTLY
CROSSED PARTS OF NH SO FAR...BUT ABOUT AN HOUR OR SO TO THE W THE
MORE CONCENTRATED LIFT IS PRODUCING AN AREA OF LIGHT SN THRU THE
HUDSON VALLEY. THAT WILL OVERSPREAD SWRN NH THRU THE SEACOAST THRU
MORNING.
PREVIOUS DISCUSSION...NEW ENGLAND REMAINS ON THE DOWNSTREAM SIDE
OF A SLOWLY ADVANCING UPPER TROF. THIS FAVORABLY PLACES THE AREA
ON THE WAA SIDE...AND COUPLED WITH ANY S/WV TROF ROTATING THRU THE
LARGER FLOW...WX WILL REMAIN UNSETTLED.
ONE SUCH STRONGER S/WV TROF WILL MOVE THRU THE ERN GREAT LAKES
TODAY. THIS WILL ENHANCE SLY FLOW INTO THE AREA...AND DEVELOP A
WEAK SFC TROF IN THE REGION. THIS PROVIDES A FOCUS FOR SN SHOWERS
THRU TODAY. HI-RES GUIDANCE SUGGEST THIS IS MOST LIKELY ACROSS NH
FOR THE EARLY PART OF THE DAY. REGIONAL RADAR STARTING TO SHOW
ECHOES DEVELOPING TO THE SW...LENDING SOME CREDIBILITY TO THOSE
SOLUTIONS. QPF WILL BE LIGHT...BUT AROUND AN INCH OF ACCUMULATION
IS POSSIBLE THRU NOON FOR NH. ACTIVITY SHIFTS EWD IN THE
AFTERNOON...AND MOST LIKELY AREA FOR SN SHOWERS SHIFTS TO COASTAL
WRN ME. WILL HAVE TO KEEP AN EYE ON WRN ZONES AGAIN LATER
TODAY...AS LATEST HRRR RUNS DEVELOP BANDS OF SN SHOWERS THAT MOVE
OFF THE GREAT LAKES AS CAA PICKS UP.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY/...
FEEL THAT WE TAKE A BRIEF BREAK TONIGHT WITH THE PRECIP.
HOWEVER...LINGERING LOW LEVEL MOISTURE AND WEAK LIFT
ALOFT...CANNOT RULE OUT A STRAY SN SHOWER. POP GENERALLY STAYS
AROUND SLIGHT CHANCE FOR THE AREA. ALSO EXPECT TO SEE SIMILAR
CONDITIONS TO TONIGHT. WITH GENERAL CLOUD COVER...BUT SOME BREAKS
DEVELOPING. THOSE AREAS WILL BE ABLE TO QUICKLY COOL OFF...BUT
TOUGH TO IDENTIFY OUTSIDE OF A COUPLE HOURS BEFORE.
UPPER TROF AXIS IS SET TO CROSS THE AREA THU. EXPECT MORE SN
SHOWERS TO FORM ALONG AND AHEAD OF IT. LATE IN THE DAY STRONG CAA
LOOKS LIKELY. IN ADDITION TO FALLING TEMPS...WINDS WILL BECOME
GUSTY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
A NARROW RIDGE OF HIGH PRESSURE WILL BUILD IN FROM THE WEST THURSDAY
NIGHT BRINGING A BRIEF PERIOD OF CLEARING SKIES AND
DIMINISHING WINDS. THIS WILL ALLOW TEMPERATURES TO PLUMMET AFTER
MIDNIGHT BOTTOMING OUT AT 5 BELOW TO NEAR ZERO NORTH AND RANGING
THROUGH THE SINGLE NUMBERS SOUTH.
NEXT IN A SERIES OF WEAK MOISTURE STARVED CLIPPER SYSTEMS WILL
GRADUALLY PUSH IN FROM THE WEST ON FRIDAY. THIS WILL BRING INCREASING
CLOUDS IN THE AFTERNOON AND A CHANCE OF SNOW SHOWERS IN NORTHWEST
ZONES BY LATE IN THE DAY. HIGH TEMPS WILL AVERAGE OUTWELL BELOW
NORMAL WITH READINGS ONLY REACHING 5 TO 15 NORTH AND MID TEENS TO
MID 20S SOUTH.
WEAK SURFACE LOW WILL CROSS NORTHERN NEW ENGLAND FRIDAY NIGHT
DRIVING AN ARCTIC FRONT THROUGH THE REGION BY SATURDAY MORNING.
EXPECT SNOW SHOWERS AND SQUALLS OVERNIGHT WITH SEVERAL INCHES OF
ACCUMULATION POSSIBLE IN THE MOUNTAINS AND FOOTHILLS. LOW
TEMPERATURES WILL DIP TO 5 BELOW TO 5 ABOVE NORTH AND 5 TO 10
DEGREES SOUTH.
STRONG NORTHWEST FLOW WILL KICK IN BEHIND DEPARTING LOW PRESSURE ON
SATURDAY USHERING IN SOME OF THE COLDEST AIR OF THE SEASON.
DEEP UPPER LOW SETTLING INTO THE NORTHEAST WILL KEEP CLOUDS AND
SNOW SHOWERS IN THE FORECAST THROUGH THE DAY. ONCE AGAIN UPSLOPE
AREAS IN THE MOUNTAINS WILL LIKELY SEE SOME ADDITIONAL MINOR
ACCUMULATIONS. HIGH TEMPS WILL RANGE THROUGH THE SINGLE NUMBERS
NORTH AND TEENS SOUTH.
UPPER LOW WILL SHIFT EAST SATURDAY NIGHT BUT INTENSE NORTHWEST FLOW
WILL CONTINUE ACROSS THE REGION AS SURFACE HIGH PRESSURE BEGINS
TO BUILD IN FROM THE WEST. SHOULD SEE SNOW SHOWER ACTIVITY
DIMINISH OVERNIGHT WITH AT LEAST PARTIAL CLEARING AFTER MIDNIGHT.
DESPITE THE WINDS EXPECT LOW TEMPS TO DIP TO 10 TO 15 BELOW NORTH
AND 5 TO 10 BELOW SOUTH. THIS IN COMBINATION WITH THE STRONG
WINDS WILL RESULT IN DANGEROUS WIND CHILLS OVERNIGHT AND WILL
LIKELY EXCEED WIND CHILL WARNING CRITERIA ACROSS A GOOD PORTION
OF THE FORECAST AREA.
WINDS WILL SLOWLY DIMINISH ON SUNDAY AS HIGH PRESSURE CONTINUES TO
BUILD IN FROM THE WEST. LOOKING FOR A MIX OF SUN AND CLOUDS IN
THE SOUTH WITH MOUNTAIN CLOUDS GRADUALLY CLEARING DURING THE
AFTERNOON. HIGH TEMPS WILL ONLY RANGE THROUGH THE SINGLE NUMBERS
NORTH AND LOWER TO MID TEENS SOUTH.
HIGH PRESSURE WILL CREST OVER THE REGION SUNDAY NIGHT. SHOULD SEE
ANOTHER VERY COLD NIGHT WITH LOWS OF 5 TO 10 BELOW NORTH AND 5 BELOW
TO 5 ABOVE SOUTH.
NEXT SHORTWAVE WILL PUSH HIGH CLOUDS INTO THE REGION BEFORE DAYBREAK
ON MONDAY AS A BROAD AREA OF OVER-RUNNING PUSHES IN FROM THE
WEST. HIGH PRESSURE WILL SHIFT OFFSHORE MONDAY MORNING AND CLOUDS
WILL LOWER AND THICKEN MONDAY AFTERNOON AS LIGHT SNOW OR SNOW
SHOWERS PUSH IN FROM THE WEST. EXPECT SOME MINOR ACCUMULATIONS BY
LATE IN THE DAY AND INTO MONDAY EVENING...BUT NOT LOOKING LIKE A
BIG DEAL AT THIS POINT IN TIME.
MORE SUBSTANTIAL SYSTEM MAY BE ON TAP FOR TUESDAY AS SHORTWAVE
HITS THE EAST COAST AND SPINS UP A COASTAL LOW BUT MODELS SHOWING
SOME BIG DIFFS IN TRACK AND TIMING WITH THIS FEATURE.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM...FORECAST AREA REMAINS IN CONTROL OF A BROAD UPPER
TROF. THIS IS KEEPING THE WX A LITTLE UNSETTLED...AND WILL
CONTINUE TO DO SO THRU THU. AREAS OF MVFR CIGS ARE SLOWLY MOVING
INTO AND THRU THE AREA...AND WILL BE MOST LIKELY ACROSS NH THE
FIRST PART OF TODAY. WRN ME WILL SEE MVFR CIGS ADVANCE INTO THOSE
ZONES BY THE AFTERNOON. WITHIN THE SFC TROF...SNWFL WILL BE
POSSIBLE...WITH AREAS OF IFR. CONFIDENCE IS LOW ON EXACTLY WHERE
AND HOW LONG IFR CONDITIONS LAST...BUT AGAIN MOST LIKELY AREAS ARE
ACROSS NH TERMINALS. TROF AXIS CROSSES THE AREA THU...WITH SHSN
LIKELY TO FORM AGAIN.
LONG TERM...AREAS MVFR CEILINGS THURSDAY EVENING...BECOMING VFR.
VFR FRIDAY WITH AREAS OF MVFR CEILINGS IN THE MOUNTAINS FRIDAY
AFTERNOON. AREAS OF MVFR CEILINGS/VSBY FRIDAY NIGHT AND SATURDAY.
VFR ON SUNDAY.
&&
.MARINE...
SHORT TERM...HIGH SEAS ARE GRADUALLY TRANSITIONING TO LONG PERIOD
SWELL. WITH SOME WAVE HEIGHTS STILL OVER 7 FT...WILL CONTINUE THE
SCA FOR HAZARDOUS SEAS THRU MORNING. AS COLD FNT CROSSES THE
WATERS LATE THU...A BRIEF PERIOD OF GALE FORCE WIND GUSTS IS
POSSIBLE. RIGHT NOW MOST LIKELY AREAS ARE S OF CAPE
ELIZABETH...AND A GALE WATCH HAS BEEN ISSUED.
LONG TERM...GALES LIKELY SATURDAY INTO SUNDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 AM EST THIS
MORNING FOR ANZ150-152-154.
GALE WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING
FOR ANZ154.
&&
$$
NEAR TERM...LEGRO
SHORT TERM...LEGRO
LONG TERM...SINSABAUGH
AVIATION...LEGRO/SINSABAUGH
MARINE...LEGRO/SINSABAUGH
AREA FORECAST DISCUSSION
NWS GRAY ME
351 AM EST WED FEB 10 2016
.SYNOPSIS...
THE REGION REMAINS UNDER WEAK LOW PRESSURE TODAY. THIS WILL BE THE
FOCUS FOR SNOW SHOWERS...WHICH WILL BRING LIGHT ACCUMULATIONS
GENERALLY BUT UP TO SEVERAL INCHES IN THE MOUNTAINS. CLOUDY
WEATHER LINGERS TONIGHT...AHEAD OF AN APPROACHING COLD FRONT SET
TO CROSS THE AREA THURSDAY. SNOW SHOWERS WILL BE LIKELY ALONG AND
AHEAD OF THAT FRONT...BEFORE COLDER AIR ARRIVES. WE HAVE A BRIEF
BREAK IN STORE FRIDAY...BUT THEN A STRONG COLD FRONT DRIVES
THROUGH THE REGION AND THE COLDEST AIR OF THE SEASON SETTLES IN
FOR THE WEEKEND.
&&
.NEAR TERM /TODAY/...
NEW ENGLAND REMAINS ON THE DOWNSTREAM SIDE OF A SLOWLY ADVANCING
UPPER TROF. THIS FAVORABLY PLACES THE AREA ON THE WAA SIDE...AND
COUPLED WITH ANY S/WV TROF ROTATING THRU THE LARGER FLOW...WX WILL
REMAIN UNSETTLED.
ONE SUCH STRONGER S/WV TROF WILL MOVE THRU THE ERN GREAT LAKES
TODAY. THIS WILL ENHANCE SLY FLOW INTO THE AREA...AND DEVELOP A
WEAK SFC TROF IN THE REGION. THIS PROVIDES A FOCUS FOR SN SHOWERS
THRU TODAY. HI-RES GUIDANCE SUGGEST THIS IS MOST LIKELY ACROSS NH
FOR THE EARLY PART OF THE DAY. REGIONAL RADAR STARTING TO SHOW
ECHOES DEVELOPING TO THE SW...LENDING SOME CREDIBILITY TO THOSE
SOLUTIONS. QPF WILL BE LIGHT...BUT AROUND AN INCH OF ACCUMULATION
IS POSSIBLE THRU NOON FOR NH. ACTIVITY SHIFTS EWD IN THE
AFTERNOON...AND MOST LIKELY AREA FOR SN SHOWERS SHIFTS TO COASTAL
WRN ME. WILL HAVE TO KEEP AN EYE ON WRN ZONES AGAIN LATER
TODAY...AS LATEST HRRR RUNS DEVELOP BANDS OF SN SHOWERS THAT MOVE
OFF THE GREAT LAKES AS CAA PICKS UP.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY/...
FEEL THAT WE TAKE A BRIEF BREAK TONIGHT WITH THE PRECIP.
HOWEVER...LINGERING LOW LEVEL MOISTURE AND WEAK LIFT
ALOFT...CANNOT RULE OUT A STRAY SN SHOWER. POP GENERALLY STAYS
AROUND SLIGHT CHANCE FOR THE AREA. ALSO EXPECT TO SEE SIMILAR
CONDITIONS TO TONIGHT. WITH GENERAL CLOUD COVER...BUT SOME BREAKS
DEVELOPING. THOSE AREAS WILL BE ABLE TO QUICKLY COOL OFF...BUT
TOUGH TO IDENTIFY OUTSIDE OF A COUPLE HOURS BEFORE.
UPPER TROF AXIS IS SET TO CROSS THE AREA THU. EXPECT MORE SN
SHOWERS TO FORM ALONG AND AHEAD OF IT. LATE IN THE DAY STRONG CAA
LOOKS LIKELY. IN ADDITION TO FALLING TEMPS...WINDS WILL BECOME
GUSTY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
A NARROW RIDGE OF HIGH PRESSURE WILL BUILD IN FROM THE WEST THURSDAY
NIGHT BRINGING A BRIEF PERIOD OF CLEARING SKIES AND
DIMINISHING WINDS. THIS WILL ALLOW TEMPERATURES TO PLUMMET AFTER
MIDNIGHT BOTTOMING OUT AT 5 BELOW TO NEAR ZERO NORTH AND RANGING
THROUGH THE SINGLE NUMBERS SOUTH.
NEXT IN A SERIES OF WEAK MOISTURE STARVED CLIPPER SYSTEMS WILL
GRADUALLY PUSH IN FROM THE WEST ON FRIDAY. THIS WILL BRING INCREASING
CLOUDS IN THE AFTERNOON AND A CHANCE OF SNOW SHOWERS IN NORTHWEST
ZONES BY LATE IN THE DAY. HIGH TEMPS WILL AVERAGE OUTWELL BELOW
NORMAL WITH READINGS ONLY REACHING 5 TO 15 NORTH AND MID TEENS TO
MID 20S SOUTH.
WEAK SURFACE LOW WILL CROSS NORTHERN NEW ENGLAND FRIDAY NIGHT
DRIVING AN ARCTIC FRONT THROUGH THE REGION BY SATURDAY MORNING.
EXPECT SNOW SHOWERS AND SQUALLS OVERNIGHT WITH SEVERAL INCHES OF
ACCUMULATION POSSIBLE IN THE MOUNTAINS AND FOOTHILLS. LOW
TEMPERATURES WILL DIP TO 5 BELOW TO 5 ABOVE NORTH AND 5 TO 10
DEGREES SOUTH.
STRONG NORTHWEST FLOW WILL KICK IN BEHIND DEPARTING LOW PRESSURE ON
SATURDAY USHERING IN SOME OF THE COLDEST AIR OF THE SEASON.
DEEP UPPER LOW SETTLING INTO THE NORTHEAST WILL KEEP CLOUDS AND
SNOW SHOWERS IN THE FORECAST THROUGH THE DAY. ONCE AGAIN UPSLOPE
AREAS IN THE MOUNTAINS WILL LIKELY SEE SOME ADDITIONAL MINOR
ACCUMULATIONS. HIGH TEMPS WILL RANGE THROUGH THE SINGLE NUMBERS
NORTH AND TEENS SOUTH.
UPPER LOW WILL SHIFT EAST SATURDAY NIGHT BUT INTENSE NORTHWEST FLOW
WILL CONTINUE ACROSS THE REGION AS SURFACE HIGH PRESSURE BEGINS
TO BUILD IN FROM THE WEST. SHOULD SEE SNOW SHOWER ACTIVITY
DIMINISH OVERNIGHT WITH AT LEAST PARTIAL CLEARING AFTER MIDNIGHT.
DESPITE THE WINDS EXPECT LOW TEMPS TO DIP TO 10 TO 15 BELOW NORTH
AND 5 TO 10 BELOW SOUTH. THIS IN COMBINATION WITH THE STRONG
WINDS WILL RESULT IN DANGEROUS WIND CHILLS OVERNIGHT AND WILL
LIKELY EXCEED WIND CHILL WARNING CRITERIA ACROSS A GOOD PORTION
OF THE FORECAST AREA.
WINDS WILL SLOWLY DIMINISH ON SUNDAY AS HIGH PRESSURE CONTINUES TO
BUILD IN FROM THE WEST. LOOKING FOR A MIX OF SUN AND CLOUDS IN
THE SOUTH WITH MOUNTAIN CLOUDS GRADUALLY CLEARING DURING THE
AFTERNOON. HIGH TEMPS WILL ONLY RANGE THROUGH THE SINGLE NUMBERS
NORTH AND LOWER TO MID TEENS SOUTH.
HIGH PRESSURE WILL CREST OVER THE REGION SUNDAY NIGHT. SHOULD SEE
ANOTHER VERY COLD NIGHT WITH LOWS OF 5 TO 10 BELOW NORTH AND 5 BELOW
TO 5 ABOVE SOUTH.
NEXT SHORTWAVE WILL PUSH HIGH CLOUDS INTO THE REGION BEFORE DAYBREAK
ON MONDAY AS A BROAD AREA OF OVER-RUNNING PUSHES IN FROM THE
WEST. HIGH PRESSURE WILL SHIFT OFFSHORE MONDAY MORNING AND CLOUDS
WILL LOWER AND THICKEN MONDAY AFTERNOON AS LIGHT SNOW OR SNOW
SHOWERS PUSH IN FROM THE WEST. EXPECT SOME MINOR ACCUMULATIONS BY
LATE IN THE DAY AND INTO MONDAY EVENING...BUT NOT LOOKING LIKE A
BIG DEAL AT THIS POINT IN TIME.
MORE SUBSTANTIAL SYSTEM MAY BE ON TAP FOR TUESDAY AS SHORTWAVE
HITS THE EAST COAST AND SPINS UP A COASTAL LOW BUT MODELS SHOWING
SOME BIG DIFFS IN TRACK AND TIMING WITH THIS FEATURE.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM...FORECAST AREA REMAINS IN CONTROL OF A BROAD UPPER
TROF. THIS IS KEEPING THE WX A LITTLE UNSETTLED...AND WILL
CONTINUE TO DO SO THRU THU. AREAS OF MVFR CIGS ARE SLOWLY MOVING
INTO AND THRU THE AREA...AND WILL BE MOST LIKELY ACROSS NH THE
FIRST PART OF TODAY. WRN ME WILL SEE MVFR CIGS ADVANCE INTO THOSE
ZONES BY THE AFTERNOON. WITHIN THE SFC TROF...SNWFL WILL BE
POSSIBLE...WITH AREAS OF IFR. CONFIDENCE IS LOW ON EXACTLY WHERE
AND HOW LONG IFR CONDITIONS LAST...BUT AGAIN MOST LIKELY AREAS ARE
ACROSS NH TERMINALS. TROF AXIS CROSSES THE AREA THU...WITH SHSN
LIKELY TO FORM AGAIN.
LONG TERM...AREAS MVFR CEILINGS THURSDAY EVENING...BECOMING VFR.
VFR FRIDAY WITH AREAS OF MVFR CEILINGS IN THE MOUNTAINS FRIDAY
AFTERNOON. AREAS OF MVFR CEILINGS/VSBY FRIDAY NIGHT AND SATURDAY.
VFR ON SUNDAY.
&&
.MARINE...
SHORT TERM...HIGH SEAS ARE GRADUALLY TRANSITIONING TO LONG PERIOD
SWELL. WITH SOME WAVE HEIGHTS STILL OVER 7 FT...WILL CONTINUE THE
SCA FOR HAZARDOUS SEAS THRU MORNING. AS COLD FNT CROSSES THE
WATERS LATE THU...A BRIEF PERIOD OF GALE FORCE WIND GUSTS IS
POSSIBLE. RIGHT NOW MOST LIKELY AREAS ARE S OF CAPE
ELIZABETH...AND A GALE WATCH HAS BEEN ISSUED.
LONG TERM...GALES LIKELY SATURDAY INTO SUNDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 AM EST THIS
MORNING FOR ANZ150-152-154.
GALE WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING
FOR ANZ154.
&&
$$
NEAR TERM...LEGRO
SHORT TERM...LEGRO
LONG TERM...SINSABAUGH
AVIATION...LEGRO/SINSABAUGH
MARINE...LEGRO/SINSABAUGH
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
635 PM EST THU FEB 11 2016
.SYNOPSIS...
SCATTERED SNOW SHOWERS SHOULD END TONIGHT AS HIGH PRESSURE BUILDS
IN. A COLD FRONT WILL BRING MORE SNOW CHANCES FRIDAY AND
SATURDAY...WITH MUCH COLDER TEMPERATURES FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
WITH 6PM UPDATE...TWEAKED HOURLY POPS AND TEMPERATURES...KEEPING
SCATTERED SNOW SHOWERS IN THE FORECAST SLIGHTLY LONGER FOR THE
TIER OF COUNTIES JUST NORTH OF PITTSBURGH WHERE ECHOES HAVE HELD
ON THE LONGEST. ALTHOUGH THE VERY COLD AIR IS NOT EXPECTED TO MOVE
INTO THE REGION UNTIL TOMORROW NIGHT...LATEST HRRR RUNS SUGGEST
TEMPERATURES COULD PLUMMET ALONG INTERSTATE 80 IF SKIES MANAGE TO
CLEAR OUT. THINK THE CLOUDS WILL HANG IN LONG ENOUGH TO PREVENT
THIS FROM HAPPENING...BUT WILL KEEP AN EYE ON THIS THROUGHOUT THE
NIGHT. PREVIOUS DISCUSSION FOLLOWS.
SCATTERED LAKE ENHANCED SNOW SHOULD CONTINUE TO TAPER OFF THRU THE
EVE AS MDL PROGGED AND OBSERVED UPSTREAM SOUNDINGS SHOW LWRG TEMP
INVERSIONS...AND WKNG LAPSE RATES. BLDG HIGH PRESSURE SHOULD
BRING CLRG SKIES TONIGHT. TEMPS SHOULD AVG AROUND 15 DEG BELOW
SEASONAL LVLS USING THE LATEST NR TERM CONSENSUS BLENDED
GUIDANCE.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
THE NEXT SHORTWAVE IS PROGGED TO CROSS THE LWR OH VLY/MID ATLANTIC
RGN FRI BRINGING INCRG LGT SNOW CHCS. ANOTHER SHORTWAVE...AND
ASSOCIATED COLD FRONT...IS EXPD TO CROSS THE RGN FRI EVE WITH
BETTER CHCS FOR SNOW SHOWERS. THE SNOW SHOWERS SHOULD CONTINUE
UNDER UPR TROFG AND LAKE/TERRAIN ENHANCEMENT LATER FRI NGT AND
SAT...THOUGH ACCUMULATIONS ARE EXPD TO REMAIN BELOW ADVISORY
CRITERIA AS DRY ARCTIC AIR RESULTS IN UNFAVORABLE MOISTURE CONTENT
IN THE SNOW GROWTH RGN. BLDG HIGH PRESSURE SAT NGT/SUN SHOULD
BRING DRY WEATHER.
WIND WITH SUFFICIENT PRES GRADIENT AND COLD TEMPS FRIDAY NIGHT
THRU SOMETIME SAT WILL LIKELY RESULT IN ADVISORY LVL WIND CHILLS
ACRS MUCH OF THE AREA. DIMINISHING WINDS MAY PROVIDE FOR LESSER
CHCS OF WIND CHILL ADVISORIES SAT NGT/ERLY SUN...THOUGH TEMPS NR
OR BELOW ZERO ARE EXPD. TEMPS WERE MODIFIED SLIGHTLY FROM
SUPERBLENDED GUIDANCE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
FAST MOVING SHORTWAVE WILL BRING A CHANCE FOR SNOW LATER SUNDAY
NIGHT INTO MONDAY AS TEMPERATURES MOVE TOWARD SEASONAL AVERAGES
TO START THE WEEK. MODELS HAVE DIFFERING SOLUTIONS FOR SOUTHERN
STREAM STORM SYSTEM INTENSIFYING AND MOVING NORTHEAST LATER
MONDAY INTO TUESDAY. SPLIT THE DIFFERENCE BETWEEN WPC PROGS AND
THE SUPERBLEND...WITH HIGHEST POPS INTO THE SOUTHEAST RIDGES.
THIS WILL BE FOLLOWED BY A CLIPPER TYPE SYSTEM WEDNESDAY WITH
CHANCE POPS. TEMPERATURES WILL BE NEAR THE SEASONAL NORM. HIGH
PRESSURE LOOKS TO GIVE A DRY DAY THURSDAY.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS EXPECTED OVERNIGHT AND INTO FRIDAY MORNING BEFORE
THE NEXT SYSTEM BRINGS ANOTHER ROUND OF SNOW AND FLIGHT
RESTRICTION FRIDAY AFTERNOON/EVENING.
CLEAR SKIES THIS EVENING STRONGER WESTERLY WINDS WILL SUBSIDE BY
MID EVENING.
.OUTLOOK.../FRIDAY THROUGH TUESDAY/...
RESTRICTIONS WILL BE POSSIBLE IN SNOW SHOWERS LATER FRIDAY INTO
SATURDAY. THE NEXT CHANCE FOR WIDESPREAD IFR WILL BE WITH LOW
PRESSURE MONDAY AND TUESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GAYLORD MI
332 PM EST WED FEB 10 2016
.NEAR TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 332 PM EST WED FEB 10 2016
HAZARDOUS WEATHER POTENTIAL...CONTINUED LAKE EFFECT SNOW AND COLD.
NORTHERN MI REMAINS BETWEEN LOW PRESSURE IN NEW ENGLAND...AND HIGH
PRESSURE NOSING SE-WARD FROM CENTRAL CANADA. TROFFING REMAINS IN
PLACE ACROSS THE LAKES REGION...PRODUCED IN PART BY THE GREAT
LAKES THEMSELVES. A SLIGHT TENDENCY FOR THIS TROFFING TO RELAX
TONIGHT AS RIDGING TO OUR WEST BECOMES STRONGER. THAT WILL BACK
1000-850MB WINDS EVER SO SLIGHTLY...TO A BORDERLINE NW/NNW BY
MIDNIGHT. LAKE EFFECT SNOW CONTINUES IN NW LOWER...AND VERY SMALL
PORTIONS OF NE LOWER (ROGERS TO APN) AND EASTERN UPPER (FAR
WESTERN MACK). ONGOING ACTIVITY APPEARS TO HAVE BEEN SOMEWHAT
DISRUPTED BY DIURNAL HEATING (SUCH AS IT IS). SNOW TRENDS ARE THE
MAIN CONCERN.
THE LOSS OF DIURNAL HEATING SHOW ALLOW FOR SOME REORGANIZATION
TOWARD LATE EVENING...THOUGH A CONTINUED DEEPLY DRY AIRMASS WILL
KEEP THINGS FROM GETTING INSANELY OUT OF LINE. LATEST HRRR RUN LINES
UP NICELY WITH RECENT RADAR/OB TRENDS AND PREVIOUS FORECAST
THINKING. IN PARTICULAR...DOMINANT BANDS ARE AGAIN EXPECTED TO SET
UP EITHER SIDE OF TVC. LOCALIZED 4-6 INCH ACCUMS AGAIN LIKELY...
PERHAPS EVEN HIGHER. PRESSURE GRADIENT DOES RELAX A BIT TONIGHT.
COMBINED WITH LOSS OF HEATING/MIXING...WINDS EVERYWHERE BUT
ALONG THE IMMEDIATE COASTLINE WILL TREND DOWNWARD. SO WILL SEE LESS
IN THE WAY OF BLOWING/DRIFTING SNOW.
WITH THE ABOVE TRENDS...HEALTHY SNOW AMOUNTS BUT LESS WIND/BLSN...
WILL REPLACE THE ONGOING WARNINGS WITH ADVISORIES. THE CURRENT
ADVISORY COUNTIES WILL REMAIN AS SUCH. ALL ADVISORIES WILL RUN THRU
NOON THURSDAY.
ELSEWHERE...SHSN WILL CONTINUE TO PESTER ROGERS CITY/APN AREA...WITH
1-3 INCH ACCUMS THERE. THE SLIGHT BACKING TO THE WINDS WILL PUSH
SHSN INTO FAR WESTERN CHIP AS WELL AS MACK...WITH 1-3 INCH ACCUMS
ALSO REASONABLE THERE. OUTSIDE OF THE SNOWBELTS...CURRENT CLOUD
COVER HAS A STRONG DIURNAL COMPONENT...AND ANTICIPATE AT LEAST
PARTIAL CLEARING JUST EAST OF THE I-75 CORRIDOR IN BOTH PENINSULAS.
MIN TEMPS WILL RANGE FROM AROUND 10F IN NW LOWER NEAR LAKE
MI...TO NEARLY -10F AT THE SAULT. HAVE GONE BELOW GUIDANCE MIN TEMPS
WHERE PARTIAL CLEARING IS EXPECTED.
&&
.SHORT TERM...(THURSDAY THROUGH SATURDAY)
ISSUED AT 332 PM EST WED FEB 10 2016
PATTERN SYNOPSIS/FORECAST: FULL-LATITUDE LONG WAVE TROUGH DOMINATES
EASTERN NORTH AMERICA WITH HIGH AMPLITUDE RIDGING ALONG THE WEST
COAST AND UP INTO ALASKA OPENING THE DOOR FOR ARCTIC AIR TO PLUNGE
INTO THE EASTERN CONUS. PATTERN BREAKS NEXT WEEK WITH RISING
HEIGHTS AND MODERATING TEMPERATURES.
PRIMARY FORECAST CONCERNS: CONTINUED LAKE EFFECT SNOW SHOWERS
THURSDAY/THURSDAY NIGHT...SNOW ALONG THE NEXT COLD FRONT FRIDAY WITH
MORE SNOW SHOWERS/BLOWING SNOW FRIDAY NIGHT. LOW WIND CHILLS FRIDAY
NIGHT INTO SATURDAY.
THURSDAY...THERMAL TROUGH BE EAST OF MICHIGAN BY THURSDAY
MORNING...AND BOUNDARY LAYER FLOW WEAKENS AS PRESSURE GRADIENT
RELAXES. INVERSION HEIGHTS WILL DECREASE AS MORE SUBSIDENCE WORKS
INTO NORTHERN MICHIGAN. SNOW SHOWERS TO START THE DAY WEST OF I-75
AND POSSIBLY FAR NORTHEAST LOWER /PRESQUE ISLE-ALPENA/. WINDS
GRADUALLY BACK THROUGHOUT THE DAY...WITH THE CHANGING WIND DIRECTION
LIKELY FANNING OUT THE SNOW SHOWERS AND ALSO BRINGING THEM EASTWARD
TOWARD THE I-75 CORRIDOR. WE MAY ALSO SEE SOME LAKE EFFECT SNOW
SHOWERS MOVE BACK INTO CHIPPEWA COUNTY AS THE FLOW TURNS MORE
WESTERLY. WILL HAVE TO WATCH FOR ANY LAKE VORTEX DEVELOPMENT GIVEN
THE WEAKENING BOUNDARY LAYER FLOW...WHICH COULD DISRUPT THE BANDING.
A FEW ADDITIONAL INCHES OF SNOW POSSIBLE IN THE HEAVIEST BANDS.
LOW LEVEL WINDS NEARLY DUE WEST THURSDAY NIGHT WHICH WILL DICTATE
THE ORIENTATION OF THE SNOW BANDS...FOCUSING ON THE M-32 CORRIDOR.
SECONDARY PUSH OF COLD AIR DROPPING IN FROM THE NORTH EXPECTED TO
ARRIVE ACROSS LAKE SUPERIOR/UPPER MICHIGAN DURING THE EARLY MORNING
HOURS FRIDAY. CONVERGENCE/FRONTOGENESIS ALONG THIS BOUNDARY RAISES
SOME CONCERNS ABOUT SNOWFALL POTENTIAL ACROSS FAR NORTHERN CHIPPEWA
COUNTY AS ADDED LOW LEVEL FORCING PUSHES INVERSION HEIGHTS BACK UP
TOWARD 700MB. THIS COULD RESULT IN SEVERAL INCHES OF SNOW
ACCUMULATION...ESPECIALLY IF THIS BAND IS PERSISTENT OVER A SEVERAL
HOUR PERIOD.
FRIDAY...OUR SECONDARY COLD FRONT ARRIVES WITH THE COLDEST AIR OF
THE WINTER. THERE WILL LIKELY BE A BRIEF BURST OF HEAVIER SNOW WITH
THIS BOUNDARY AS IT SAGS SOUTHWARD....WITH A NICE AXIS OF DEEPER
MOISTURE AND MID LEVEL DIV-Q. IF THE BAND REMAINS TRANSITORY...THEN
GENERALLY AN INCH OR TWO SNOW FOR MOST AREAS LOOKS GOOD...WITH
WEST/NORTHWEST FLOW LAKE ENHANCEMENT POSSIBLY BOOSTING TOTALS IN
SOME AREAS. THIS BURST OF SNOW COULD HAVE SOME TRAVEL IMPLICATIONS
/ALBEIT BRIEFLY/ AND IS SOMETHING TO KEEP AN EYE ON. BEHIND THE
FRONT...EXPECT NORTH-NORTHWEST FLOW LAKE EFFECT TO SET UP AS THE
COLDEST AIR OF THE EVENT ADVECTS ACROSS THE UPPER LAKES /850MB
TEMPERATURES BELOW -25C BY FRIDAY EVENING/. TEMPERATURES LIKELY
FALL DURING THE AFTERNOON BEHIND THE FRONT...AND WITH A BRISK
NORTH/NORTHWEST WIND DEVELOPING...ANTICIPATING WIND CHILLS TO FALL
BELOW ZERO DURING THE AFTERNOON.
SNOW SHOWERS CONTINUE FRIDAY NIGHT AS LOW LEVEL WINDS VEER TO A 330-
340 DEGREE ORIENTATION. SET UP SEEMS FAVORABLE FOR A DOMINANT TWO-
LAKE BAND /SIMILAR TO OUR CURRENT SET-UP OF LAKE EFFECT/ THAT
IMPACTS AN AREA ALONG/WEST OF THE US-131 CORRIDOR. BUT BY THIS TIME
850MB TEMPERATURES AT OR BELOW -25C WILL HAVE AN IMPACT ON SNOWFLAKE
GROWTH PROCESSES RESULTING IN MUCH SMALLER FLAKE SIZES THAT WILL NOT
ACCUMULATE AS MUCH. SMALL FLAKES ARE ALSO MORE LIKELY TO BLOW AROUND
WITH GUSTY WINDS...WHICH CAN CREATE SIGNIFICANT VISIBILITY ISSUES.
SEVERAL MORE INCHES OF ACCUMULATION WILL BE POSSIBLE. TEMPERATURES
WILL FALL BELOW ZERO IN MANY AREAS FRIDAY NIGHT /OUTSIDE OF COASTAL
AREAS/...WITH READINGS OF -20 DEGF POSSIBLE IN AREAS THAT SEE SOME
CLEARING.
SATURDAY...ONE WORD TO DESCRIBE TEMPERATURES...BRUTAL. COLDEST AIR
OF THE WINTER IMPACTING MICHIGAN WITH ARCTIC HIGH GRADUALLY BUILDING
INTO THE REGION. SINGLE DIGIT HIGHS IN MOST AREAS...ALTHOUGH A FEW
LOCATIONS MAY NOT REACH ZERO. WIND CHILL READINGS OF -15 TO -25
DEGREES DURING THE MORNING...WHICH COULD POTENTIALLY PUT US CLOSE TO
WIND CHILL ADVISORY CRITERIA. SNOW SHOWERS CONTINUING IN NORTHWEST
FLOW AREAS...WITH VERY SMALL FLAKE SIZE BUT POTENTIALLY POOR
VISIBILITY IN SOME LOCATIONS.
&&
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 332 PM EST WED FEB 10 2016
THE LONG RANGE MODELS ARE IN CONSENSUS OF SEVERAL AREAS OF UPPER
LEVEL DISTURBANCES AND A COUPLE SURFACE LOWS PRODUCING CHANCES OF
SNOW THROUGHOUT THE EXTENDED PERIOD...WITH SUNDAY NIGHT INTO MONDAY
HAVING THE BEST CHANCES FOR WIDESPREAD WARM ADVECTION SNOW ON THE
WESTERN PERIPHERY OF THE DEPARTING HIGH PRESSURE. LATE SUNDAY NIGHT
INTO MONDAY MAY ALSO SEE SOME LAKE ENHANCEMENT ON THE STRONG SOUTH-
SOUTHWESTERLY WINDS AHEAD OF AN APPROACHING CLIPPER SYSTEM ALONG THE
LAKE MICHIGAN SHORELINES...ESPECIALLY THE US-2 CORRIDOR OF EASTERN
UPPER. THE WINDS VEER TO NORTHWESTERLY BEHIND THE DEPARTING CLIPPER
SYSTEM BY TUESDAY MORNING WITH MUCH DRIER AIR AND A NARROW RIDGE OF
HIGH PRESSURE. COLD TEMPERATURES WILL VERY LIKELY AT LEAST CREATE
LAKE CLOUDS...IF NOT SQUEEZE SOME LIGHT SNOW OUT AT TIMES TUESDAY.
MODELS THEN HINT AT ANOTHER CLIPPER SYSTEM APPROACHING THE GREAT
LAKES REGION MID-WEEK.
LOWS SUNDAY MORNING WILL DROP TO 5 TO 10 DEGREES BELOW ZERO WITH
WIND CHILLS BETWEEN 15 TO 20 BELOW ZERO. DAYTIME HIGHS WILL REACH
INTO THE TEENS ABOVE ZERO SUNDAY AND MODERATE TO THE UPPER 20S TO
MID 30S BY TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1242 PM EST WED FEB 10 2016
HIGHLY VARIABLE CONDITIONS AT TVC. MAINLY MVFR ELSEWHERE.
LAKE EFFECT SNOW/CLOUDS CONTINUE...AS COLD AIR ENTERS THE REGION
FROM THE NNW. ONGOING WIND DIRECTIONS TARGETS MAINLY TVC...TO A
LESSER DEGREE MBL/APN...AND PLN NOT AT ALL. MVFR TO VFR CIGS WILL
BE COMMON OUTSIDE OF SHSN. INSIDE OF SHSN...MVFR TO IFR CONDITIONS
EXPECTED.
NW WINDS (GUSTING TO 20-25KT) WILL DIMINISH SOMEWHAT TONIGHT.
&&
.MARINE...
ISSUED AT 332 PM EST WED FEB 10 2016
NW WINDS WILL SLOWLY DIMINISH...AS ARCTIC HIGH PRESSURE ADVANCES
FROM CENTRAL CANADA. SMALL CRAFT ADVISORIES ARE SET TO EXPIRE
EARLY THU MORNING...AND THAT HOLD FOR A LITTLE WHILE. HOWEVER...W
TO NW WINDS WILL INCREASE THU NIGHT...AND ADDITIONAL ADVISORIES
COULD WELL BE NEEDED THEN.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 10 AM EST THURSDAY FOR MIZ019>021-
025>027-031>033.
LH...SMALL CRAFT ADVISORY UNTIL 6 AM EST THURSDAY FOR LHZ345>349.
LM...SMALL CRAFT ADVISORY UNTIL 6 AM EST THURSDAY FOR LMZ323-341-342-
344>346.
LS...NONE.
&&
$$
NEAR TERM...JZ
SHORT TERM...KEYSOR
LONG TERM...TJL
AVIATION...JZ
MARINE...JZ
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1257 PM EST WED FEB 10 2016
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 309 AM EST WED FEB 10 2016
LAKE EFFECT SNOWS WILL CONTINUE ALONG THE LAKESHORE COUNTIES WITH UP
TO AN ADDITIONAL SIX INCHES POSSIBLE THROUGH MID DAY THURSDAY. MOST
AREAS WILL SEE A LULL IN THE SNOW THURSDAY NIGHT...THEN ANOTHER
CLIPPER SYSTEM WILL MOVE BY FRIDAY BRINGING MORE SNOW. HOWEVER AT
THIS POINT IT APPEARS THIS SNOW WILL BE LIGHTER. IT WILL REMAIN
COLD WITH DAYTIME HIGHS ONLY IN THE UPPER TEENS TO MID 20S.
THE WEEKEND SHOULD REMAIN COLD...THEN WE SEE A SLIGHTLY WARM UP FOR
MONDAY AND TUESDAY. ANOTHER PERIOD OF SNOW SHOULD MOVE IN FOR
SUNDAY NIGHT THROUGH MONDAY NIGHT.
&&
.UPDATE...
ISSUED AT 950 AM EST WED FEB 10 2016
THE UPDATED ZONE FORECAST AND WINTER STORM WARNING FOR KALAMAZOO
COUNTY HAVE BEEN ISSUED.
UPDATE ISSUED AT 922 AM EST WED FEB 10 2016
I WILL VERY SHORTLY PUT KALAMAZOO COUNTY IN A WINTER STORM
WARNING SINCE WE HAVE HAD A REPORT OF 9 INCHES IN ALAMO IN
NORTHWEST KALAMAZOO COUNTY. RADAR DATA (STORM TOTAL SNOW DEPTH
FROM 88D) SHOWS THAT SNOW BAND EXTENDED FROM PORT SHELDON THROUGH
HOLLAND...TO JUST WEST OF THE CITY OF ALLEGAN THROUGH ALAMO. THE
LATEST RUNS OF THE HRRR AND RAP MODEL SUGGEST THE SNOW BANDS
SHOULD CONTINUE TO IMPACT WESTERN KALAMAZOO COUNTY THE REST OF THE DAY.
BASED ON THAT...IT MAKES SENSE TO ADD THEM TO THE WARNING...SO I
WILL AND I WILL RUN THE WARNING TO MATCH THE OTHERS... 10 AM
THURSDAY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 330 AM EST WED FEB 10 2016
WILL STAY THE COURSE WITH THE HEADLINES.
INVERSION LEVELS DROP A BIT TODAY AS LAST NIGHTS SHORT WAVE MOVES
EAST. HOWEVER EVEN AT 7K FEET THIS WILL BE ENOUGH TO MAINTAIN
HEALTHY LAKE EFFECT BANDS. OVERALL EXPECT VERY LITTLE CHANGE IN THE
PATTERN AND INTENSITY OF THE SNOW TODAY INTO THIS EVENING. THE FLOW
REMAINS 330-335 THROUGH THIS PERIOD. SO THE HEAVIER BANDS WILL
REMAIN OVER THE SAME AREAS...MAINLY OVER THE WESTERN HALF OF THE
LAKESHORE COUNTIES...AND ALL OF VAN BUREN COUNTY. SOME AREAS MAY
PICK AN ADDITIONAL SIX INCHES OF SNOW...AND LOCALLY MORE. WINDS
WILL ALSO REMAIN A FACTOR...CAUSING BLOWING AND DRIFTING FOR MUCH OF
TODAY. MEANWHILE INLAND AREAS WILL ONLY SEE OCCASIONAL LIGHT SNOW
WITH ACCUMS GENERALLY AN INCH OR LESS.
EXPECT THE SNOW WILL BEGIN TO SHOW A DIMINISHING TREND AFTER 06Z
TONIGHT AND INTO THURSDAY MORNING. ITS POSSIBLE WE MAY BE ABLE TO
CANCEL THE HEADLINES AND BIT EARLY...BUT WILL CONTINUE TO MONITOR
TRENDS.
THE INVERSION LEVELS DROP TO AROUND 4K FEET FOR A BIT THURSDAY
NIGHT. NOT EXPECTING THE SNOW WILL COMPLETE END...BUT THE INTENSITY
WILL DROP OFF.
THE LAKE EFFECT WILL PERK UP AGAIN ON FRIDAY WITH ANOTHER CLIPPER
MOVING IN. HOWEVER THE INVERSION LEVELS SEEM TO ONLY BUMP UP A
BIT...SO EXPECTING MOSTLY LIGHT SNOW. GENERALLY TWO INCHES OR LESS
FROM THIS SYSTEM FOR THE LAKESHORE AND LESS THAN AN INCH INLAND.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 330 AM EST WED FEB 10 2016
PATTERN STARTS OUT QUITE AMPLIFIED IN THE LONG TERM PERIOD...WITH A
DEEP TROUGH OVER THE EASTERN HALF OF THE CONUS. VERY COLD AIR WILL
BE PUSHING SOUTH THROUGH THE GREAT LAKES REGION WITHIN THIS TROUGH
FRIDAY NIGHT INTO SATURDAY. 850MB TEMPS ARE STILL FORECAST TO HIT
-26C TO -27C AT 700AM SAT. LOWS SATURDAY MORNING WILL LIKELY BE IN
THE SINGLE DIGITS ABOVE AND BELOW ZERO F. LAKE EFFECT SNOW SHOWERS
WILL CONTINUE FRIDAY NIGHT AND SATURDAY...BUT GIVEN THE VERY COLD
AIR AND NORTHERLY FLOW...NOT MUCH IN THE WAY OF ACCUMULATION OR
IMPACT.
SATURDAY NIGHT INTO SUNDAY SHOULD BE MAINLY DRY AND COLD WITH ARCTIC
HIGH PRESSURE DRIFTING EAST THROUGH THE GREAT LAKES.
THE FORECAST BECOMES A BIT MORE DIFFICULT SUNDAY AFTERNOON INTO
EARLY NEXT WEEK...AS THE FLOW BECOMES ONE OF A FAST ZONAL NATURE.
TIMING SHORTWAVE/S IN A ZONAL FLOW AT DAY 5 AND 6 IS A TOUGH CALL.
BOTH THE GFS AND ECMWF BRING A SHORTWAVE TROUGH THROUGH OUR AREA
THOUGH SUNDAY NIGHT AND MONDAY. HAVE MAINTAINED THE CHANCE POPS 30-
50 PCT FOR SOME LIGHT SNOW. THE SURFACE FEATURES ASSOCIATED WITH THE
SHORTWAVE ARE WEAK WITH THE ECMWF. THE SYSTEM IS A BIT MORE
DEVELOPED IN THE GFS. AT THIS POINT...SIDING WITH THE WEAKER ECMWF
AND NOT EXPECTING MUCH IN THE WAY OF ACCUMULATION. TUESDAY ANOTHER
SYSTEM APPROACHES AND HAVE LOW CONFIDENCE OUT AT DAY 7 IN A ZONAL
REGIME. HAVE SMALL CHANCES FOR SNOW IN THE FORECAST FOR TUESDAY.
AFTER A COLD WEEKEND TEMPERATURES REBOUND BACK TOWARD NORMAL EARLY
NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1256 PM EST WED FEB 10 2016
MOST TERMINALS ARE SEEING PREVAILING MVFR CONDITIONS WITH SOME
SPOTTY IFR WITH CLOUDS AND LAKE EFFECT SNOW SHOWERS EARLY THIS
AFTERNOON. KMKG AND KAZO ARE SEEING MORE PREVAILING IFR-LIFR IN
HEAVIER SNOW SHOWERS AT TIMES. WE EXPECT MORE OF THE SAME THROUGH
THE DAYLIGHT HOURS TODAY.
WINDS ARE EXPECTED TO SHIFT MORE NNW THIS EVENING AND DIMINISH A
BIT...WHICH SHOULD TAKE THE LOWER CONDITIONS CLOSER TO THE
LAKESHORE. WE EXPECT INLAND LOCATIONS MAY GO TO VFR WITH SOME
CLEARING EVEN POSSIBLE.
WINDS WILL SHIFT TO BE FROM A MORE WRLY DIRECTION ON THU WHICH
SHOULD DRIVE SNOW SHOWERS INLAND ONCE AGAIN. THE SNOW SHOWERS
SHOULD NOT BE AS INTENSE AS TODAY...BUT WILL DROP CONDITIONS TO
MVFR WITH SOME IFR POSSIBLE.
&&
.MARINE...
ISSUED AT 950 AM EST WED FEB 10 2016
WE HAVE ENDED THE GALE WARNING AND REPLACED IT WITH A SMALL CRAFT
ADVISORY UNTIL 1 PM THURSDAY.
&&
.HYDROLOGY...
ISSUED AT 1233 PM EST WED FEB 10 2016
DOWNWARD TRENDS CONTINUE ON THE MAPLE RIVER WITH MINIMAL CONCERNS
FOR ADDITIONAL FLOODING IN THE NEAR FUTURE.
PRECIPITATION FORECASTS THROUGH THE NEXT 7 DAYS ACCOUNT FOR LESS
THAN THREE-QUARTERS OF AN INCH ALONG THE LAKESHORE AND LESS THAN
HALF AN INCH INLAND. THIS TRANSLATES TO LITTLE OR NO CONCERN WITH
PRECIPITATION TYPE MOSTLY CONSISTING OF SNOW.
TEMPERATURES WILL STAY WELL BELOW FREEZING TODAY THROUGH THE
WEEKEND...POSSIBLY REACHING FREEZING BY NEXT TUESDAY. ICE MAY
BEGIN TO DEVELOP ONCE AGAIN OVER THE WEEKEND AS OVERNIGHT LOWS
BOTTOM OUT IN THE SINGLE DIGITS. THESE TEMPERATURES DO NOT LAST
VERY LONG THOUGH...AND THE RETURN TO 30S NEXT WEEK MAY HELP
MITIGATE ANY ICE JAMMING. IT IS THE MAIN FOCUS GOING THROUGH
SATURDAY AND SUNDAY. OTHERWISE...FAIRLY QUITE RIVER-WISE.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER STORM WARNING UNTIL 10 AM EST THURSDAY FOR MIZ037-043-056-
064-071-072.
WINTER WEATHER ADVISORY UNTIL 10 AM EST THURSDAY FOR MIZ038-050.
LM...SMALL CRAFT ADVISORY UNTIL 1 PM EST THURSDAY FOR LMZ844>849.
&&
$$
UPDATE...WDM
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...DUKE
AVIATION...NJJ
HYDROLOGY...JAM
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1233 PM EST WED FEB 10 2016
LATEST UPDATE...
HYDRO
.SYNOPSIS...
ISSUED AT 309 AM EST WED FEB 10 2016
LAKE EFFECT SNOWS WILL CONTINUE ALONG THE LAKESHORE COUNTIES WITH UP
TO AN ADDITIONAL SIX INCHES POSSIBLE THROUGH MID DAY THURSDAY. MOST
AREAS WILL SEE A LULL IN THE SNOW THURSDAY NIGHT...THEN ANOTHER
CLIPPER SYSTEM WILL MOVE BY FRIDAY BRINGING MORE SNOW. HOWEVER AT
THIS POINT IT APPEARS THIS SNOW WILL BE LIGHTER. IT WILL REMAIN
COLD WITH DAYTIME HIGHS ONLY IN THE UPPER TEENS TO MID 20S.
THE WEEKEND SHOULD REMAIN COLD...THEN WE SEE A SLIGHTLY WARM UP FOR
MONDAY AND TUESDAY. ANOTHER PERIOD OF SNOW SHOULD MOVE IN FOR
SUNDAY NIGHT THROUGH MONDAY NIGHT.
&&
.UPDATE...
ISSUED AT 950 AM EST WED FEB 10 2016
THE UPDATED ZONE FORECAST AND WINTER STORM WARNING FOR KALAMAZOO
COUNTY HAVE BEEN ISSUED.
UPDATE ISSUED AT 922 AM EST WED FEB 10 2016
I WILL VERY SHORTLY PUT KALAMAZOO COUNTY IN A WINTER STORM
WARNING SINCE WE HAVE HAD A REPORT OF 9 INCHES IN ALAMO IN
NORTHWEST KALAMAZOO COUNTY. RADAR DATA (STORM TOTAL SNOW DEPTH
FROM 88D) SHOWS THAT SNOW BAND EXTENDED FROM PORT SHELDON THROUGH
HOLLAND...TO JUST WEST OF THE CITY OF ALLEGAN THROUGH ALAMO. THE
LATEST RUNS OF THE HRRR AND RAP MODEL SUGGEST THE SNOW BANDS
SHOULD CONTINUE TO IMPACT WESTERN KALAMAZOO COUNTY THE REST OF THE DAY.
BASED ON THAT...IT MAKES SENSE TO ADD THEM TO THE WARNING...SO I
WILL AND I WILL RUN THE WARNING TO MATCH THE OTHERS... 10 AM
THURSDAY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 330 AM EST WED HEB 10 2016
WILL STAY THE COURSE WITH THE HEADLINES.
INVERSION LEVELS DROP A BIT TODAY AS LAST NIGHTS SHORT WAVE MOVES
EAST. HOWEVER EVEN AT 7K FEET THIS WILL BE ENOUGH TO MAINTAIN
HEALTHY LAKE EFFECT BANDS. OVERALL EXPECT VERY LITTLE CHANGE IN THE
PATTERN AND INTENSITY OF THE SNOW TODAY INTO THIS EVENING. THE FLOW
REMAINS 330-335 THROUGH THIS PERIOD. SO THE HEAVIER BANDS WILL
REMAIN OVER THE SAME AREAS...MAINLY OVER THE WESTERN HALF OF THE
LAKESHORE COUNTIES...AND ALL OF VAN BUREN COUNTY. SOME AREAS MAY
PICK AN ADDITIONAL SIX INCHES OF SNOW...AND LOCALLY MORE. WINDS
WILL ALSO REMAIN A FACTOR...CAUSING BLOWING AND DRIFTING FOR MUCH OF
TODAY. MEANWHILE INLAND AREAS WILL ONLY SEE OCCASIONAL LIGHT SNOW
WITH ACCUMS GENERALLY AN INCH OR LESS.
EXPECT THE SNOW WILL BEGIN TO SHOW A DIMINISHING TREND AFTER 06Z
TONIGHT AND INTO THURSDAY MORNING. ITS POSSIBLE WE MAY BE ABLE TO
CANCEL THE HEADLINES AND BIT EARLY...BUT WILL CONTINUE TO MONITOR
TRENDS.
THE INVERSION LEVELS DROP TO AROUND 4K FEET FOR A BIT THURSDAY
NIGHT. NOT EXPECTING THE SNOW WILL COMPLETE END...BUT THE INTENSITY
WILL DROP OFF.
THE LAKE EFFECT WILL PERK UP AGAIN ON FRIDAY WITH ANOTHER CLIPPER
MOVING IN. HOWEVER THE INVERSION LEVELS SEEM TO ONLY BUMP UP A
BIT...SO EXPECTING MOSTLY LIGHT SNOW. GENERALLY TWO INCHES OR LESS
FROM THIS SYSTEM FOR THE LAKESHORE AND LESS THAN AN INCH INLAND.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 330 AM EST WED FEB 10 2016
PATTERN STARTS OUT QUITE AMPLIFIED IN THE LONG TERM PERIOD...WITH A
DEEP TROUGH OVER THE EASTERN HALF OF THE CONUS. VERY COLD AIR WILL
BE PUSHING SOUTH THROUGH THE GREAT LAKES REGION WITHIN THIS TROUGH
FRIDAY NIGHT INTO SATURDAY. 850MB TEMPS ARE STILL FORECAST TO HIT
-26C TO -27C AT 700AM SAT. LOWS SATURDAY MORNING WILL LIKELY BE IN
THE SINGLE DIGITS ABOVE AND BELOW ZERO F. LAKE EFFECT SNOW SHOWERS
WILL CONTINUE FRIDAY NIGHT AND SATURDAY...BUT GIVEN THE VERY COLD
AIR AND NORTHERLY FLOW...NOT MUCH IN THE WAY OF ACCUMULATION OR
IMPACT.
SATURDAY NIGHT INTO SUNDAY SHOULD BE MAINLY DRY AND COLD WITH ARCTIC
HIGH PRESSURE DRIFTING EAST THROUGH THE GREAT LAKES.
THE FORECAST BECOMES A BIT MORE DIFFICULT SUNDAY AFTERNOON INTO
EARLY NEXT WEEK...AS THE FLOW BECOMES ONE OF A FAST ZONAL NATURE.
TIMING SHORTWAVE/S IN A ZONAL FLOW AT DAY 5 AND 6 IS A TOUGH CALL.
BOTH THE GFS AND ECMWF BRING A SHORTWAVE TROUGH THROUGH OUR AREA
THOUGH SUNDAY NIGHT AND MONDAY. HAVE MAINTAINED THE CHANCE POPS 30-
50 PCT FOR SOME LIGHT SNOW. THE SURFACE FEATURES ASSOCIATED WITH THE
SHORTWAVE ARE WEAK WITH THE ECMWF. THE SYSTEM IS A BIT MORE
DEVELOPED IN THE GFS. AT THIS POINT...SIDING WITH THE WEAKER ECMWF
AND NOT EXPECTING MUCH IN THE WAY OF ACCUMULATION. TUESDAY ANOTHER
SYSTEM APPROACHES AND HAVE LOW CONFIDENCE OUT AT DAY 7 IN A ZONAL
REGIME. HAVE SMALL CHANCES FOR SNOW IN THE FORECAST FOR TUESDAY.
AFTER A COLD WEEKEND TEMPERATURES REBOUND BACK TOWARD NORMAL EARLY
NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 719 AM EST WED FEB 10 2016
STEADY STATE LAKE EFFECT SNOW WILL CONTINUE TODAY AND INTO MOST OF
TONIGHT. THE WAY THE BANDS WILL BE SITUATED IN A NORTH-NORTHWEST
FLOW...KLAN...KBTL AND KJXN WILL NOT BE AFFECTED TOO MUCH. THERE
WILL BE SOME OCCASIONAL MVFR AT THESE INLAND TAF SITES TODAY...BUT
MUCH OF THE NEXT 24 HOURS WILL BE VFR.
THE BANDS WILL LIKELY AFFECT KAZO THE MOST AS THE BAND SHIFTS IN
AND OUT OF THAT TAF SITE. MVFR WILL BE LIKELY THERE WITH
OCCASIONAL IFR CONDITIONS.
KMKG AND KGRR WILL SEE SNOW SHOWERS AS WELL...BUT CONDITIONS WILL
BE VARYING MORE VFR TO MVFR.
A NORTHWEST WIND OF 10 TO 20 KNOTS WILL BE COMMON PLACE TODAY.
&&
.MARINE...
ISSUED AT 950 AM EST WED FEB 10 2016
WE HAVE ENDED THE GALE WARNING AND REPLACED IT WITH A SMALL CRAFT
ADVIOSRY UNTIL 1 PM THURSDAY.
&&
.HYDROLOGY...
ISSUED AT 1233 PM EST WED FEB 10 2016
DOWNWARD TRENDS CONTINUE ON THE MAPLE RIVER WITH MINIMAL CONCERNS
FOR ADDITIONAL FLOODING IN THE NEAR FUTURE.
PRECIPITATION FORECASTS THROUGH THE NEXT 7 DAYS ACCOUNT FOR LESS
THAN THREE-QUARTERS OF AN INCH ALONG THE LAKESHORE AND LESS THAN
HALF AN INCH INLAND. THIS TRANSLATES TO LITTLE OR NO CONCERN WITH
PRECIPITATION TYPE MOSTLY CONSISTING OF SNOW.
TEMPERATURES WILL STAY WELL BELOW FREEZING TODAY THROUGH THE
WEEKEND...POSSIBLY REACHING FREEZING BY NEXT TUESDAY. ICE MAY
BEGIN TO DEVELOP ONCE AGAIN OVER THE WEEKEND AS OVERNIGHT LOWS
BOTTOM OUT IN THE SINGLE DIGITS. THESE TEMPERATURES DO NOT LAST
VERY LONG THOUGH...AND THE RETURN TO 30S NEXT WEEK MAY HELP
MITIGATE ANY ICE JAMMING. IT IS THE MAIN FOCUS GOING THROUGH
SATURDAY AND SUNDAY. OTHERWISE...FAIRLY QUITE RIVER-WISE.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER STORM WARNING UNTIL 10 AM EST THURSDAY FOR MIZ037-043-056-
064-071-072.
WINTER WEATHER ADVISORY UNTIL 10 AM EST THURSDAY FOR MIZ038-050.
LM...SMALL CRAFT ADVISORY UNTIL 1 PM EST THURSDAY FOR LMZ844>849.
&&
$$
UPDATE...WDM
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...DUKE
AVIATION...DUKE
HYDROLOGY...JAM
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
950 AM EST WED FEB 10 2016
LATEST UPDATE...
UPDATE/MARINE
.SYNOPSIS...
ISSUED AT 309 AM EST WED FEB 10 2016
LAKE EFFECT SNOWS WILL CONTINUE ALONG THE LAKESHORE COUNTIES WITH UP
TO AN ADDITIONAL SIX INCHES POSSIBLE THROUGH MID DAY THURSDAY. MOST
AREAS WILL SEE A LULL IN THE SNOW THURSDAY NIGHT...THEN ANOTHER
CLIPPER SYSTEM WILL MOVE BY FRIDAY BRINGING MORE SNOW. HOWEVER AT
THIS POINT IT APPEARS THIS SNOW WILL BE LIGHTER. IT WILL REMAIN
COLD WITH DAYTIME HIGHS ONLY IN THE UPPER TEENS TO MID 20S.
THE WEEKEND SHOULD REMAIN COLD...THEN WE SEE A SLIGHTLY WARM UP FOR
MONDAY AND TUESDAY. ANOTHER PERIOD OF SNOW SHOULD MOVE IN FOR
SUNDAY NIGHT THROUGH MONDAY NIGHT.
&&
.UPDATE...
ISSUED AT 950 AM EST WED FEB 10 2016
THE UPDATED ZONE FORECAST AND WINTER STORM WARNING FOR KALAMAZOO
COUNTY HAVE BEEN ISSUED.
UPDATE ISSUED AT 922 AM EST WED FEB 10 2016
I WILL VERY SHORTLY PUT KALAMAZOO COUNTY IN A WINTER STORM
WARNING SINCE WE HAVE HAD A REPORT OF 9 INCHES IN ALAMO IN
NORTHWEST KALAMAZOO COUNTY. RADAR DATA (STORM TOTAL SNOW DEPTH
FROM 88D) SHOWS THAT SNOW BAND EXTENDED FROM PORT SHELDON THROUGH
HOLLAND...TO JUST WEST OF THE CITY OF ALLEGAN THROUGH ALAMO. THE
LATEST RUNS OF THE HRRR AND RAP MODEL SUGGEST THE SNOW BANDS
SHOULD CONTINUE TO IMPACT WESTERN KALAMAZOO COUNTY THE REST OF THE DAY.
BASED ON THAT...IT MAKES SENSE TO ADD THEM TO THE WARNING...SO I
WILL AND I WILL RUN THE WARNING TO MATCH THE OTHERS... 10 AM
THURSDAY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 330 AM EST WED HEB 10 2016
WILL STAY THE COURSE WITH THE HEADLINES.
INVERSION LEVELS DROP A BIT TODAY AS LAST NIGHTS SHORT WAVE MOVES
EAST. HOWEVER EVEN AT 7K FEET THIS WILL BE ENOUGH TO MAINTAIN
HEALTHY LAKE EFFECT BANDS. OVERALL EXPECT VERY LITTLE CHANGE IN THE
PATTERN AND INTENSITY OF THE SNOW TODAY INTO THIS EVENING. THE FLOW
REMAINS 330-335 THROUGH THIS PERIOD. SO THE HEAVIER BANDS WILL
REMAIN OVER THE SAME AREAS...MAINLY OVER THE WESTERN HALF OF THE
LAKESHORE COUNTIES...AND ALL OF VAN BUREN COUNTY. SOME AREAS MAY
PICK AN ADDITIONAL SIX INCHES OF SNOW...AND LOCALLY MORE. WINDS
WILL ALSO REMAIN A FACTOR...CAUSING BLOWING AND DRIFTING FOR MUCH OF
TODAY. MEANWHILE INLAND AREAS WILL ONLY SEE OCCASIONAL LIGHT SNOW
WITH ACCUMS GENERALLY AN INCH OR LESS.
EXPECT THE SNOW WILL BEGIN TO SHOW A DIMINISHING TREND AFTER 06Z
TONIGHT AND INTO THURSDAY MORNING. ITS POSSIBLE WE MAY BE ABLE TO
CANCEL THE HEADLINES AND BIT EARLY...BUT WILL CONTINUE TO MONITOR
TRENDS.
THE INVERSION LEVELS DROP TO AROUND 4K FEET FOR A BIT THURSDAY
NIGHT. NOT EXPECTING THE SNOW WILL COMPLETE END...BUT THE INTENSITY
WILL DROP OFF.
THE LAKE EFFECT WILL PERK UP AGAIN ON FRIDAY WITH ANOTHER CLIPPER
MOVING IN. HOWEVER THE INVERSION LEVELS SEEM TO ONLY BUMP UP A
BIT...SO EXPECTING MOSTLY LIGHT SNOW. GENERALLY TWO INCHES OR LESS
FROM THIS SYSTEM FOR THE LAKESHORE AND LESS THAN AN INCH INLAND.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 330 AM EST WED FEB 10 2016
PATTERN STARTS OUT QUITE AMPLIFIED IN THE LONG TERM PERIOD...WITH A
DEEP TROUGH OVER THE EASTERN HALF OF THE CONUS. VERY COLD AIR WILL
BE PUSHING SOUTH THROUGH THE GREAT LAKES REGION WITHIN THIS TROUGH
FRIDAY NIGHT INTO SATURDAY. 850MB TEMPS ARE STILL FORECAST TO HIT
-26C TO -27C AT 700AM SAT. LOWS SATURDAY MORNING WILL LIKELY BE IN
THE SINGLE DIGITS ABOVE AND BELOW ZERO F. LAKE EFFECT SNOW SHOWERS
WILL CONTINUE FRIDAY NIGHT AND SATURDAY...BUT GIVEN THE VERY COLD
AIR AND NORTHERLY FLOW...NOT MUCH IN THE WAY OF ACCUMULATION OR
IMPACT.
SATURDAY NIGHT INTO SUNDAY SHOULD BE MAINLY DRY AND COLD WITH ARCTIC
HIGH PRESSURE DRIFTING EAST THROUGH THE GREAT LAKES.
THE FORECAST BECOMES A BIT MORE DIFFICULT SUNDAY AFTERNOON INTO
EARLY NEXT WEEK...AS THE FLOW BECOMES ONE OF A FAST ZONAL NATURE.
TIMING SHORTWAVE/S IN A ZONAL FLOW AT DAY 5 AND 6 IS A TOUGH CALL.
BOTH THE GFS AND ECMWF BRING A SHORTWAVE TROUGH THROUGH OUR AREA
THOUGH SUNDAY NIGHT AND MONDAY. HAVE MAINTAINED THE CHANCE POPS 30-
50 PCT FOR SOME LIGHT SNOW. THE SURFACE FEATURES ASSOCIATED WITH THE
SHORTWAVE ARE WEAK WITH THE ECMWF. THE SYSTEM IS A BIT MORE
DEVELOPED IN THE GFS. AT THIS POINT...SIDING WITH THE WEAKER ECMWF
AND NOT EXPECTING MUCH IN THE WAY OF ACCUMULATION. TUESDAY ANOTHER
SYSTEM APPROACHES AND HAVE LOW CONFIDENCE OUT AT DAY 7 IN A ZONAL
REGIME. HAVE SMALL CHANCES FOR SNOW IN THE FORECAST FOR TUESDAY.
AFTER A COLD WEEKEND TEMPERATURES REBOUND BACK TOWARD NORMAL EARLY
NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 719 AM EST WED FEB 10 2016
STEADY STATE LAKE EFFECT SNOW WILL CONTINUE TODAY AND INTO MOST OF
TONIGHT. THE WAY THE BANDS WILL BE SITUATED IN A NORTH-NORTHWEST
FLOW...KLAN...KBTL AND KJXN WILL NOT BE AFFECTED TOO MUCH. THERE
WILL BE SOME OCCASIONAL MVFR AT THESE INLAND TAF SITES TODAY...BUT
MUCH OF THE NEXT 24 HOURS WILL BE VFR.
THE BANDS WILL LIKELY AFFECT KAZO THE MOST AS THE BAND SHIFTS IN
AND OUT OF THAT TAF SITE. MVFR WILL BE LIKELY THERE WITH
OCCASIONAL IFR CONDITIONS.
KMKG AND KGRR WILL SEE SNOW SHOWERS AS WELL...BUT CONDITIONS WILL
BE VARYING MORE VFR TO MVFR.
A NORTHWEST WIND OF 10 TO 20 KNOTS WILL BE COMMON PLACE TODAY.
&&
.MARINE...
ISSUED AT 950 AM EST WED FEB 10 2016
WE HAVE ENDED THE GALE WARNING AND REPLACED IT WITH A SMALL CRAFT
ADVIOSRY UNTIL 1 PM THURSDAY.
&&
.HYDROLOGY...
ISSUED AT 249 PM EST TUE FEB 9 2016
THE MAPLE RIVER AT MAPLE RAPIDS CONTINUES TO SHOW IMPROVEMENT AS
EXPECTED. REALISTICALLY...THE RATE AT WHICH IT IS FALLING MAY
ALLOW IT TO BE DROPPED BY FRIDAY. THE MAIN STORY THEN SHIFTS TO
THE COLDEST AIR OF THE SEASON...POSSIBLY LEADING TO ICE BUILD UP
RIGHT THROUGH THE WEEKEND.
TEMPERATURES WILL GRADUALLY BECOME COOLER EACH DAY THIS WEEK WITH
DAYTIME HIGHS BELOW FREEZING AND OVERNIGHT LOWS FALLING INTO THE
TEENS THROUGH FRIDAY. THE BRUNT OF THE COLD AIR SEEMS TO MAKE IT
IN BY THE WEEKEND WITH LOWS IN THE SINGLE DIGITS FOR MANY
LOCATIONS AND SOME AREAS POSSIBLY DIPPING BELOW ZERO. THIS WILL
CERTAINLY ASSIST IN ICE FORMATION FOR STREAMS AND RIVERS...BECOMING
MORE OF A FOCUS AS THE WEEK PROGRESSES.
PRECIPITATION WILL BE ALL SNOW THROUGH THE PERIOD WITH LITTLE IN
THE WAY OF RUNOFF. THE HEAVIEST SNOWFALL WILL STAY HUGGED ALONG
THE LAKE MICHIGAN BORDERING COUNTIES AND OTHER AREAS TYPICAL OF
NORTHWEST FLOW. THIS WILL JUST BE A DELAYED CONCERN IF ADDITIONAL
LIQUID MOISTURE IS RECEIVED IN THE NEAR FUTURE. AS FOR NOW...THE
TOTALS OVER THE COURSE OF THE WEEK ARE ONLY LOCALLY HIGH NEAR THE
LAKE WITH AREA WIDE AVERAGES STAYING RELATIVELY LOW WHEN
CONSIDERING THE EPISODIC NATURE OF THE EVENT.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER STORM WARNING UNTIL 10 AM EST THURSDAY FOR MIZ037-043-056-
064-071-072.
WINTER WEATHER ADVISORY UNTIL 10 AM EST THURSDAY FOR MIZ038-050.
LM...SMALL CRAFT ADVISORY UNTIL 1 PM EST THURSDAY FOR LMZ844>849.
&&
$$
UPDATE...WDM
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...DUKE
AVIATION...DUKE
HYDROLOGY...JAM
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
922 AM EST WED FEB 10 2016
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 309 AM EST WED FEB 10 2016
LAKE EFFECT SNOWS WILL CONTINUE ALONG THE LAKESHORE COUNTIES WITH UP
TO AN ADDITIONAL SIX INCHES POSSIBLE THROUGH MID DAY THURSDAY. MOST
AREAS WILL SEE A LULL IN THE SNOW THURSDAY NIGHT...THEN ANOTHER
CLIPPER SYSTEM WILL MOVE BY FRIDAY BRINGING MORE SNOW. HOWEVER AT
THIS POINT IT APPEARS THIS SNOW WILL BE LIGHTER. IT WILL REMAIN
COLD WITH DAYTIME HIGHS ONLY IN THE UPPER TEENS TO MID 20S.
THE WEEKEND SHOULD REMAIN COLD...THEN WE SEE A SLIGHTLY WARM UP FOR
MONDAY AND TUESDAY. ANOTHER PERIOD OF SNOW SHOULD MOVE IN FOR
SUNDAY NIGHT THROUGH MONDAY NIGHT.
&&
.UPDATE...
ISSUED AT 922 AM EST WED FEB 10 2016
I WILL VERY SHORTLY PUT KALAMAZOO COUNTY IN A WINTER STORM
WARNING SINCE WE HAVE HAD A REPORT OF 9 INCHES IN ALAMO IN
NORTHWEST KALAMAZOO COUNTY. RADAR DATA (STORM TOTAL SNOW DEPTH
FROM 88D) SHOWS THAT SNOW BAND EXTENDED FROM PORT SHELDON THROUGH
HOLLAND...TO JUST WEST OF THE CITY OF ALLEGAN THROUGH ALAMO. THE
LATEST RUNS OF THE HRRR AND RAP MODEL SUGGEST THE SNOW BANDS
SHOULD CONTINUE TO IMPACT WESTERN KALAMAZOO COUNTY THE REST OF THE DAY.
BASED ON THAT...IT MAKES SENSE TO ADD THEM TO THE WARNING...SO I
WILL AND I WILL RUN THE WARNING TO MATCH THE OTHERS... 10 AM
THURSDAY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 330 AM EST WED HEB 10 2016
WILL STAY THE COURSE WITH THE HEADLINES.
INVERSION LEVELS DROP A BIT TODAY AS LAST NIGHTS SHORT WAVE MOVES
EAST. HOWEVER EVEN AT 7K FEET THIS WILL BE ENOUGH TO MAINTAIN
HEALTHY LAKE EFFECT BANDS. OVERALL EXPECT VERY LITTLE CHANGE IN THE
PATTERN AND INTENSITY OF THE SNOW TODAY INTO THIS EVENING. THE FLOW
REMAINS 330-335 THROUGH THIS PERIOD. SO THE HEAVIER BANDS WILL
REMAIN OVER THE SAME AREAS...MAINLY OVER THE WESTERN HALF OF THE
LAKESHORE COUNTIES...AND ALL OF VAN BUREN COUNTY. SOME AREAS MAY
PICK AN ADDITIONAL SIX INCHES OF SNOW...AND LOCALLY MORE. WINDS
WILL ALSO REMAIN A FACTOR...CAUSING BLOWING AND DRIFTING FOR MUCH OF
TODAY. MEANWHILE INLAND AREAS WILL ONLY SEE OCCASIONAL LIGHT SNOW
WITH ACCUMS GENERALLY AN INCH OR LESS.
EXPECT THE SNOW WILL BEGIN TO SHOW A DIMINISHING TREND AFTER 06Z
TONIGHT AND INTO THURSDAY MORNING. ITS POSSIBLE WE MAY BE ABLE TO
CANCEL THE HEADLINES AND BIT EARLY...BUT WILL CONTINUE TO MONITOR
TRENDS.
THE INVERSION LEVELS DROP TO AROUND 4K FEET FOR A BIT THURSDAY
NIGHT. NOT EXPECTING THE SNOW WILL COMPLETE END...BUT THE INTENSITY
WILL DROP OFF.
THE LAKE EFFECT WILL PERK UP AGAIN ON FRIDAY WITH ANOTHER CLIPPER
MOVING IN. HOWEVER THE INVERSION LEVELS SEEM TO ONLY BUMP UP A
BIT...SO EXPECTING MOSTLY LIGHT SNOW. GENERALLY TWO INCHES OR LESS
FROM THIS SYSTEM FOR THE LAKESHORE AND LESS THAN AN INCH INLAND.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 330 AM EST WED FEB 10 2016
PATTERN STARTS OUT QUITE AMPLIFIED IN THE LONG TERM PERIOD...WITH A
DEEP TROUGH OVER THE EASTERN HALF OF THE CONUS. VERY COLD AIR WILL
BE PUSHING SOUTH THROUGH THE GREAT LAKES REGION WITHIN THIS TROUGH
FRIDAY NIGHT INTO SATURDAY. 850MB TEMPS ARE STILL FORECAST TO HIT
-26C TO -27C AT 700AM SAT. LOWS SATURDAY MORNING WILL LIKELY BE IN
THE SINGLE DIGITS ABOVE AND BELOW ZERO F. LAKE EFFECT SNOW SHOWERS
WILL CONTINUE FRIDAY NIGHT AND SATURDAY...BUT GIVEN THE VERY COLD
AIR AND NORTHERLY FLOW...NOT MUCH IN THE WAY OF ACCUMULATION OR
IMPACT.
SATURDAY NIGHT INTO SUNDAY SHOULD BE MAINLY DRY AND COLD WITH ARCTIC
HIGH PRESSURE DRIFTING EAST THROUGH THE GREAT LAKES.
THE FORECAST BECOMES A BIT MORE DIFFICULT SUNDAY AFTERNOON INTO
EARLY NEXT WEEK...AS THE FLOW BECOMES ONE OF A FAST ZONAL NATURE.
TIMING SHORTWAVE/S IN A ZONAL FLOW AT DAY 5 AND 6 IS A TOUGH CALL.
BOTH THE GFS AND ECMWF BRING A SHORTWAVE TROUGH THROUGH OUR AREA
THOUGH SUNDAY NIGHT AND MONDAY. HAVE MAINTAINED THE CHANCE POPS 30-
50 PCT FOR SOME LIGHT SNOW. THE SURFACE FEATURES ASSOCIATED WITH THE
SHORTWAVE ARE WEAK WITH THE ECMWF. THE SYSTEM IS A BIT MORE
DEVELOPED IN THE GFS. AT THIS POINT...SIDING WITH THE WEAKER ECMWF
AND NOT EXPECTING MUCH IN THE WAY OF ACCUMULATION. TUESDAY ANOTHER
SYSTEM APPROACHES AND HAVE LOW CONFIDENCE OUT AT DAY 7 IN A ZONAL
REGIME. HAVE SMALL CHANCES FOR SNOW IN THE FORECAST FOR TUESDAY.
AFTER A COLD WEEKEND TEMPERATURES REBOUND BACK TOWARD NORMAL EARLY
NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 719 AM EST WED FEB 10 2016
STEADY STATE LAKE EFFECT SNOW WILL CONTINUE TODAY AND INTO MOST OF
TONIGHT. THE WAY THE BANDS WILL BE SITUATED IN A NORTH-NORTHWEST
FLOW...KLAN...KBTL AND KJXN WILL NOT BE AFFECTED TOO MUCH. THERE
WILL BE SOME OCCASIONAL MVFR AT THESE INLAND TAF SITES TODAY...BUT
MUCH OF THE NEXT 24 HOURS WILL BE VFR.
THE BANDS WILL LIKELY AFFECT KAZO THE MOST AS THE BAND SHIFTS IN
AND OUT OF THAT TAF SITE. MVFR WILL BE LIKELY THERE WITH
OCCASIONAL IFR CONDITIONS.
KMKG AND KGRR WILL SEE SNOW SHOWERS AS WELL...BUT CONDITIONS WILL
BE VARYING MORE VFR TO MVFR.
A NORTHWEST WIND OF 10 TO 20 KNOTS WILL BE COMMON PLACE TODAY.
&&
.MARINE...
ISSUED AT 330 AM EST WED FEB 10 2016
GALE FORCE WIND NORTH OF WHITEHALL WILL DIMINISH LATE THIS MORNING.
CONDITIONS WILL REMAIN ROUGH THROUGH MOST OF THE SHORT TERM.
&&
.HYDROLOGY...
ISSUED AT 249 PM EST TUE FEB 9 2016
THE MAPLE RIVER AT MAPLE RAPIDS CONTINUES TO SHOW IMPROVEMENT AS
EXPECTED. REALISTICALLY...THE RATE AT WHICH IT IS FALLING MAY
ALLOW IT TO BE DROPPED BY FRIDAY. THE MAIN STORY THEN SHIFTS TO
THE COLDEST AIR OF THE SEASON...POSSIBLY LEADING TO ICE BUILD UP
RIGHT THROUGH THE WEEKEND.
TEMPERATURES WILL GRADUALLY BECOME COOLER EACH DAY THIS WEEK WITH
DAYTIME HIGHS BELOW FREEZING AND OVERNIGHT LOWS FALLING INTO THE
TEENS THROUGH FRIDAY. THE BRUNT OF THE COLD AIR SEEMS TO MAKE IT
IN BY THE WEEKEND WITH LOWS IN THE SINGLE DIGITS FOR MANY
LOCATIONS AND SOME AREAS POSSIBLY DIPPING BELOW ZERO. THIS WILL
CERTAINLY ASSIST IN ICE FORMATION FOR STREAMS AND RIVERS...BECOMING
MORE OF A FOCUS AS THE WEEK PROGRESSES.
PRECIPITATION WILL BE ALL SNOW THROUGH THE PERIOD WITH LITTLE IN
THE WAY OF RUNOFF. THE HEAVIEST SNOWFALL WILL STAY HUGGED ALONG
THE LAKE MICHIGAN BORDERING COUNTIES AND OTHER AREAS TYPICAL OF
NORTHWEST FLOW. THIS WILL JUST BE A DELAYED CONCERN IF ADDITIONAL
LIQUID MOISTURE IS RECEIVED IN THE NEAR FUTURE. AS FOR NOW...THE
TOTALS OVER THE COURSE OF THE WEEK ARE ONLY LOCALLY HIGH NEAR THE
LAKE WITH AREA WIDE AVERAGES STAYING RELATIVELY LOW WHEN
CONSIDERING THE EPISODIC NATURE OF THE EVENT.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER STORM WARNING UNTIL 10 AM EST THURSDAY FOR MIZ037-043-056-
064-071.
WINTER WEATHER ADVISORY UNTIL 10 AM EST THURSDAY FOR MIZ038-050-
072.
LM...GALE WARNING UNTIL 10 AM EST THIS MORNING FOR LMZ848-849.
SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LMZ844>847.
&&
$$
UPDATE...WDM
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...DUKE
AVIATION...DUKE
HYDROLOGY...JAM
MARINE...JK
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1200 AM EST WED FEB 10 2016
.UPDATE...
ISSUED AT 1026 PM EST TUE FEB 9 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW TROF DEEPENING INTO THE
UPPER GREAT LAKES THIS EVENING. WITH TROF CONTINUING TO DEEPEN...
MODELS SHOW 12HR 500MB HEIGHT FALLS OF 20-80M ACROSS LAKE
SUPERIOR/UPPER MI DURING THE NIGHT...GREATEST OVER THE E HALF OF THE
AREA. UPSTREAM...12Z CWPL SOUNDING SHOWED A SHARP INVERSION AT ABOUT
875MB WHERE TEMP WAS -28C. 00Z CWPL SOUNDING SHOWED THAT THE
INVERSION HAD WEAKENED WITH A DEEP ISOTHERMAL LAYER NOW PRESENT FROM
AROUND 900MB TO AROUND 760MB. MOISTURE DEPTH HAS ALSO INCREASED TO
AROUND 760MB/6300FT. THERE HAS BEEN RATHER PERSISTENT 28+DBZ RETURNS
IN THE ONGOING SNOW BANDS EAST OF MARQUETTE...INDICATING 1+IN/HR
SNOW RATES. SINCE DEEPENING TROF AND UPSTREAM 00Z CWPL SOUNDING
SUPPORT AN INCREASE IN LES INTENSITY OVERNIGHT INTO WED MORNING...
LES WARNING HAS BEEN HOISTED FOR MARQUETTE/ALGER COUNTIES. SEEMS
REASONABLE THAT SOME AREAS WILL REACH/EXCEED 8IN/12HR OR 12IN/24HR
WARNING CRITERIA FOR HIGH SLR SNOWFALL.
18Z MODEL GUIDANCE AND HOURLY HRRR/RAP RUNS INDICATE SLIGHT VEERING
OF WINDS DURING THE NIGHT/WED MORNING WHICH WOULD SHIFT MDT/HVY SNOW
WESTWARD INTO MORE OF THE HIGH TERRAIN OF MARQUETTE COUNTY. WIND
FIELDS ACTUALLY LOOK QUITE FAVORABLE FOR DECENT SNOW AS N WIND OVER
THE LAKE ENCOUNTERS BACKED WIND OVER THE LAND. HAVE PAINTED 24HR
SNOW AMOUNTS ENDING 00Z THU OF 8 TO LOCALLY 12IN IN THAT AREA...BUT
GIVEN THE PERSISTENCE OF HVY SNOW SO FAR THIS EVENING IN EASTERN
MARQUETTE COUNTY...THE AREA AROUND SKANDIA/CARLSHEND WILL PROBABLY
END UP WITH THE MOST SNOW...14IN OR MORE DEPENDING ON HOW LONG THE
BAND LINGERS BEFORE SHIFTING W. IN ALGER COUNTY...RAN WARNING THRU
PREVIOUS ADVY TIMEFRAME....THOUGH SNOWFALL AFTER WED MORNING
PROBABLY WON`T REQUIRE ANYTHING MORE THAN ADVY. EXPECT GREATEST SNOW
TOTALS IN ALGER COUNTY TO BE IN THE WRN PORTION OF THE COUNTY.
FINALLY...WITH BLSN...ESPECIALLY IN OPEN AREAS NEAR LAKE SUPERIOR...
THERE WILL NO DOUBT BE BRIEF WHITE-OUTS IN THE BANDS OF HVY SNOW.
OUT W...ENHANCING FACTORS INFLUENCING THE SNOW INTENSITY INTO NCNTRL
UPPER MI WILL BE WEAKER OVER WRN UPPER MI...SO NO MEANINGFUL CHANGES
WERE MADE TO FCST THERE.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 243 PM EST TUE FEB 9 2016
UPPER AIR PATTERN CONSISTS OF A 500 MB RIDGE IN THE WESTERN U.S. AND
A CLOSED 500 MB LOW IN SOUTHERN ONTARIO WITH A TROUGH IN THE GREAT
LAKES REGION. THIS TROUGH CONTINUES TO MOVE SLOWLY EAST INTO THE
LOWER GREAT LAKES TONIGHT AS THE RIDGE MOVES INTO THE ROCKIES. NAM
SHOWS DEEPER MOISTURE AND 850-500 MB Q-VECTOR CONVERGENCE MOVING
OUT OF THE ERN CWA TONIGHT.
WINDS DO NOT CHANGE MUCH AND NEITHER DOES THE COLD AIR AMOUNT
THROUGH THIS FORECAST PERIOD...SO PERSISTENCE IS THE WAY TO GO WITH
THIS FORECAST. LOOKED AT 950 MB CONVERGENCE WINDS AND THEY STAY
STRONG UNTIL WED AFTERNOON ACROSS THE WESTERN CWA ALONG LAKE
SUPERIOR AND ACROSS MARQUETTE AND ALGER COUNTIES AND FOR THIS
REASON...EXTENDED THE ADVISORY FOR ALGER AND MARQUETTE COUNTIES
UNTIL 00Z WED AND WILL GO WITH AN ADVISORY FOR ONTONAGON AND GOGEBIC
COUNTIES AND KEEP NORTHERN HOUGHTON AND KEWEENAW COUNTIES IN AN
ADVISORY THROUGH THEN. LOOKING AT BUFKIT SOUNDINGS...INVERSION
HEIGHTS REMAIN BELOW 500 FEET THROUGH THIS WHOLE FORECAST PERIOD AS
WELL. OVERALL...DID NOT MAKE MANY BIG CHANGES TO THE GOING FORECAST
EXCEPT DID BUMP UP SNOW AND QPF AMOUNTS A BIT IN NORTHERLY LAKE
EFFECT SNOW BELTS AND HAVE CATEGORICAL POPS IN THOSE AREAS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 348 PM EST TUE FEB 9 2016
NNW WINDS WILL CONTINUE WEDNESDAY NIGHT...BEFORE SHIFTING OUT OF THE
NW THURSDAY MORNING AND REMAINING OUT OF A MAINLY NW DIRECTION
THROUGH THE DAY FRIDAY. 850MB TEMPS STARTING OUT AROUND -22C...AND
ONLY BRIEFLY MODERATE SLIGHTLY TO AROUND -10C THURSDAY NIGHT BEFORE
MUCH COOLER AIR SLIDES BACK IN FOR FRIDAY. THE OVERALL PATTERN WILL
CONSIST OF A TROUGH LINGERING ACROSS LAKE SUPERIOR AS COLD/STRONG
CANADIAN HIGH PRESSURE SLOWLY SINKS ACROSS MANITOBA AND THE E
DAKOTAS/MN.
SUBTLE UPPER-LEVEL TROUGHING DIGGING SSE ACROSS THE CWA WEDNESDAY
NIGHT WILL VEER LOW-LEVEL WINDS ENOUGH TO SUPPORT ENHANCED LOW-LEVEL
CONVERGENCE BETWEEN MARQUETTE AND AU TRAIN. WITH GUSTY NNW WINDS AND
THERMO PROFILES STILL SUPPORTIVE OF MODEST LES...HAVE OPTED TO
EXTENDED THE LES ADVISORY FOR AT LEAST ALGER COUNTY THROUGH WED
NIGHT.
ENHANCING THE CONTINUED LAKE EFFECT SNOW SHOWERS WILL BE A TROUGH
SET UP ACROSS THE NW ONTARIO BORDER WITH MANITOBA AT 18Z THURSDAY.
EXPECT THE TROUGH TO SINK ACROSS LAKE SUPERIOR THURSDAY
NIGHT...BEFORE THE SFC TROUGH ITSELF PUSHES OVER FAR SE PORTIONS OF
ONTARIO FRIDAY AFTERNOON. A LINGERING THERMALLY-INDUCED TROUGH OVER
EASTERN LAKE SUPERIOR WILL AGAIN ENHANCE LOW-LEVEL CONVERGENCE AND
FOCUS LES INTO ALGER COUNTY FRI NIGHT INTO SAT. WITH A STRENGTHENING
PRESSURE GRADIENT DUE TO THE IMPINGING HIGH PRES...WINDS LOOKS TO BE
QUITE GUSTY THUR NIGHT INTO SAT. WHILE SPECIFICS ARE A BIT MUDDLED
AT THIS TIME...LES ADVISORY CONDITIONS MAY BE PRESENT AGAIN WITH THE
COMBINATION OF THE WIND AND FOCUSED LES BANDS.
A RATHER COLD 850MB CORE OF -30C WILL BRUSH THE CWA FRIDAY AFTERNOON
INTO SATURDAY MORNING. HAVE TRENDED TEMPS DOWNWARD A FEW DEGREES
DURING THIS PERIOD. WITH COLD TEMPS AND GUSTY WINDS...WIND CHILLS
WILL NEAR ADVISORY CRITERIA FOR MUCH OF THE CWA FRIDAY NIGHT.
LES QUICKLY SHIFTS TO THE EAST AS A SFC RIDGE CROSSES THE CWA SAT
NIGHT. CONDITIONS ARE SETTING UP FOR QUITE A CHILLY NIGHT WITH LIGHT
WINDS AND DRY CONDITIONS. THE ONE CAVEAT FOR VERY COLD CONDITION
WILL BE THE POSSIBILITY OF HIGH CLOUDS FILTERING ACROSS THE AREA
AHEAD OF LOW PRESSURE OVER THE NORTHERN PLAINS. HAVE TRENDED TEMPS
DOWNWARD...WITH TEENS BELOW ZERO INTERIOR WEST. AFTER DRY CONDITIONS
ON SUNDAY...TROUGHING WILL BRING LIGHT SNOW ACROSS THE REGION SUNDAY
NIGHT INTO MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1159 PM EST TUE FEB 9 2016
UNDER A NNW FLOW OF ARCTIC AIR ACROSS LAKE SUPERIOR...LAKE EFFECT
SNOW SHOWERS WILL BE THE RULE AT KIWD/KCMX/KSAW THRU THIS FCST
PERIOD...AND TYPICAL FOR LAKE EFFECT SNOW...CONDITIONS WILL BE
HIGHLY VARIABLE. PREVAILING CONDITIONS WILL LIKELY BE IFR...BUT
EXPECT PERIODS OF LIFR AND MVFR. LIFR CONDITIONS SHOULD BE MORE
LIKELY TO OCCUR AT KSAW LATE OVERNIGHT/EARLY THIS MORNING AS SLIGHTLY
VEERING WINDS SHIFT HEAVIER SNOW SHOWERS WESTWARD TO KSAW. SOMEWHAT
DRIER AIR AND A FALLING INVERSION SHOULD LEAD TO IMPROVING CONDITIONS
THIS AFTN WITH A TREND TO PREVAILING MVFR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 243 PM EST TUE FEB 9 2016
GALE FORCE GUSTS WILL CONTINUE INTO THIS EVENING OVER NORTH CENTRAL
LAKE SUPERIOR. NEXT GALES LOOK TO BE THU NIGHT AND FRI ACROSS LAKE
SUPERIOR AS NEXT SHOT OF COLD AIR MOVE IN AND PRESSURE GRADIENT
TIGHTENS UP AGAIN. FREEZING SPRAY WILL ALSO INCREASE WITH THE
HEAVIEST FREEZING SPRAY INTO WED.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST /6 PM CST/ WEDNESDAY
FOR MIZ001>003-009.
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST WEDNESDAY FOR MIZ005.
LAKE EFFECT SNOW WARNING UNTIL 7 AM EST THURSDAY FOR MIZ006.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST THURSDAY FOR
LSZ265>267.
HEAVY FREEZING SPRAY WARNING UNTIL 4 PM EST /3 PM CST/ WEDNESDAY
FOR LSZ162-263-264.
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ264.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...ROLFSON
SHORT TERM...07
LONG TERM...KF/KLUBER
AVIATION...ROLFSON
MARINE...07
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1136 AM CST WED FEB 10 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 417 AM CST WED FEB 10 2016
A BAND OF SNOW WILL MOVE ACROSS WESTERN MN. THE REST OF THE REGION
WILL BE DRY TODAY AND TONIGHT. TEMPERATURES WILL CONTINUE COOLER
THAN NORMAL...WITH LIGHT WINDS.
EARLY MORNING RADAR IMAGERY WITH RAP SURFACE ANALYSIS SHOWS A RIDGE
OF HIGH PRESSURE OVER NORTHERN MN...WITH A SURFACE LOW UPSTREAM OVER
WESTERN NORTH DAKOTA. OVER THE NEXT 24 HOURS THE SURFACE SLOW WILL
SLIDE SOUTHEAST TOWARD NEBRASKA IN RESPONSE TO A WEAK UPPER LEVEL PV
ANOMALY EMBEDDED IN NORTHWEST FLOW. AN AREA OF LIGHT SNOW WAS
ALREADY ON RADAR ACROSS THE DAKOTAS...AND THIS WILL MOVE SOUTHEAST
ALONG THE BUFFALO RIDGE. CENTRAL AND EASTERN MN...AND WESTERN WI
WILL BE DRY. MODEL GUIDANCE HAS BEEN TOO COLD THE PAST COUPLE OF
DAYS...SO INCREASED TEMPS SLIGHTLY FOR TODAYS HIGHS AND TONIGHTS
LOWS. WINDS WILL BE LIGHT AND VARIABLE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 417 AM CST WED FEB 10 2016
THE FIRST HALF OF THE LONG TERM /THROUGH SATURDAY/ WILL FEATURE A
DEEP TROUGH OVER THE EAST AND THUS A NORTHWEST FLOW REGIME OVER
THE UPPER MIDWEST. THE CWA WILL BE CONTINUOUSLY UNDER A RIDGE AXIS
UNTIL LATE IN THE WEEKEND WHICH WILL BRING TRANQUIL AND SEASONABLY
COLD CONDITIONS. THE ONLY CHANCE OF PRECIPITATION DURING THIS
PERIOD WILL BE THURSDAY NIGHT SOUTH OF THE MINNESOTA RIVER OVER
SOUTHWEST MN WHEN A RIPPLE /NOT UNLIKE THE ONE CURRENTLY IMPACTING
THE EASTERN DAKOTAS/ EXPLOITS A TEMPORARY WEAKNESS IN THE SURFACE
RIDGING. ONLY VERY LIGHT SNOW OR FLURRIES ARE EXPECTED.
THE COLDEST NIGHT WILL COME FRIDAY NIGHT AS A 1045 MB HIGH SETTLES
DIRECTLY OVERHEAD. WINDS WILL DECOUPLE LATE UNDER CLEAR SKIES
WHICH WILL ALLOW TEMPERATURES TO PLUMMET WELL BELOW ZERO ACROSS
THE CWA...AND LIKELY INTO THE -20S ACROSS PORTIONS OF CENTRAL MN
AND WEST CENTRAL WI.
THAT HIGH WILL BE WHAT FINALLY KICKS THE TROUGH OUT OF NEW ENGLAND
BY EARLY NEXT WEEK. THIS WILL MARK A TRANSITION TO A MORE
PROGRESSIVE AND ACTIVE PATTERN ACROSS THE AREA AS A RIDGE SLOWLY
ADVANCES FROM THE SOUTHWEST TO SOUTHERN HIGH PLAINS.
THE FIRST OF TWO STORM SYSTEMS WILL ARRIVE LATE SATURDAY NIGHT.
DECENT ISENTROPIC LIFT WILL GENERATE FAIRLY WIDESPREAD WAA SNOW
THAT WILL PUSH ACROSS THE REGION THROUGH SUNDAY. GFS IS MORE
BULLISH THAN THE ECMWF...BUT BOTH MODELS BRING THE POTENTIAL FOR
PLOWABLE ACCUMULATION BY SUNDAY EVENING. POPS WERE ALMOST BROUGHT
INTO THE LIKELY CATEGORY...BUT KEPT THEM JUST BELOW 55 WITH SOME
PRETTY LARGE MODEL DIFFERENCES FOR THIS TIME RANGE...NAMELY THE
LOW TRACK WHICH IS ALMOST 500 MILES BETWEEN THE 06Z GFS AND 00Z
ECMWF.
THE SECOND SYSTEM ARRIVES EARLY NEXT WEEK. WITH THE SOUTHERN RIDGE
A BIT FURTHER EAST...THIS ONE COULD WRAP UP INTO A MORE
SIGNIFICANT SYSTEM A LA THE ECMWF. STILL LARGE DIFFERENCES AMONGST
THE GUIDANCE...CERTAINLY NOT UNEXPECTED GIVEN IT IS 7 DAYS OUT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1135 AM CST WED FEB 10 2016
NOT MUCH CHANGE IN THE WEATHER IS EXPECTED THIS TAF PERIOD...WITH
THE BAND OF CLOUDS EXTENDING FROM MEMPHIS TN BACK NW TO
SASKATCHEWAN MORE OR LESS EXPECTED TO REMAIN IN PLACE THIS
PERIOD. ONLY CHANGE IS THAT THE -SN CURRENTLY FALLING IN SW/SC MN
WILL BE PULLING OUT OF MN BY 20Z. AS IT DOES SO...ANY MVFR CIGS
WILL RISE BACK TO VFR AND WILL REMAIN THERE THE REST OF THE
PERIOD. WITH A SFC HIGH WORKING ACROSS THE AREA THIS PERIOD...WE
WILL MAINTAIN LIGHT AND VARIABLE WINDS AS WELL.
KMSP...ONLY AREA OF LOWER CONFIDENCE IN TAF IS WITH WIND
DIRECTION...THOUGH THAT IS TO BE EXPECTED WITH HIGH PRESSURE
MOVING THROUGH. SPEEDS WILL REMAIN MOSTLY UNDER 5 KTS...SO THE VRB
DIRECTION WILL NOT BE A HUGE ISSUE.
/OUTLOOK FOR KMSP/
FRI...VFR. WIND NW AT 10G20 KT.
SAT...VFR. WIND E AT 5 KT.
SUN...MVFR/IFR WITH -SN LIKELY. WIND S 15 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
SHORT TERM...JRB
LONG TERM...BORGHOFF
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
417 AM CST WED FEB 10 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 417 AM CST WED FEB 10 2016
A BAND OF SNOW WILL MOVE ACROSS WESTERN MN. THE REST OF THE REGION
WILL BE DRY TODAY AND TONIGHT. TEMPERATURES WILL CONTINUE COOLER
THAN NORMAL...WITH LIGHT WINDS.
EARLY MORNING RADAR IMAGERY WITH RAP SURFACE ANALYSIS SHOWS A RIDGE
OF HIGH PRESSURE OVER NORTHERN MN...WITH A SURFACE LOW UPSTREAM OVER
WESTERN NORTH DAKOTA. OVER THE NEXT 24 HOURS THE SURFACE SLOW WILL
SLIDE SOUTHEAST TOWARD NEBRASKA IN RESPONSE TO A WEAK UPPER LEVEL PV
ANOMALY EMBEDDED IN NORTHWEST FLOW. AN AREA OF LIGHT SNOW WAS
ALREADY ON RADAR ACROSS THE DAKOTAS...AND THIS WILL MOVE SOUTHEAST
ALONG THE BUFFALO RIDGE. CENTRAL AND EASTERN MN...AND WESTERN WI
WILL BE DRY. MODEL GUIDANCE HAS BEEN TOO COLD THE PAST COUPLE OF
DAYS...SO INCREASED TEMPS SLIGHTLY FOR TODAYS HIGHS AND TONIGHTS
LOWS. WINDS WILL BE LIGHT AND VARIABLE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 417 AM CST WED FEB 10 2016
THE FIRST HALF OF THE LONG TERM /THROUGH SATURDAY/ WILL FEATURE A
DEEP TROUGH OVER THE EAST AND THUS A NORTHWEST FLOW REGIME OVER
THE UPPER MIDWEST. THE CWA WILL BE CONTINUOUSLY UNDER A RIDGE AXIS
UNTIL LATE IN THE WEEKEND WHICH WILL BRING TRANQUIL AND SEASONABLY
COLD CONDITIONS. THE ONLY CHANCE OF PRECIPITATION DURING THIS
PERIOD WILL BE THURSDAY NIGHT SOUTH OF THE MINNESOTA RIVER OVER
SOUTHWEST MN WHEN A RIPPLE /NOT UNLIKE THE ONE CURRENTLY IMPACTING
THE EASTERN DAKOTAS/ EXPLOITS A TEMPORARY WEAKNESS IN THE SURFACE
RIDGING. ONLY VERY LIGHT SNOW OR FLURRIES ARE EXPECTED.
THE COLDEST NIGHT WILL COME FRIDAY NIGHT AS A 1045 MB HIGH SETTLES
DIRECTLY OVERHEAD. WINDS WILL DECOUPLE LATE UNDER CLEAR SKIES
WHICH WILL ALLOW TEMPERATURES TO PLUMMET WELL BELOW ZERO ACROSS
THE CWA...AND LIKELY INTO THE -20S ACROSS PORTIONS OF CENTRAL MN
AND WEST CENTRAL WI.
THAT HIGH WILL BE WHAT FINALLY KICKS THE TROUGH OUT OF NEW ENGLAND
BY EARLY NEXT WEEK. THIS WILL MARK A TRANSITION TO A MORE
PROGRESSIVE AND ACTIVE PATTERN ACROSS THE AREA AS A RIDGE SLOWLY
ADVANCES FROM THE SOUTHWEST TO SOUTHERN HIGH PLAINS.
THE FIRST OF TWO STORM SYSTEMS WILL ARRIVE LATE SATURDAY NIGHT.
DECENT ISENTROPIC LIFT WILL GENERATE FAIRLY WIDESPREAD WAA SNOW
THAT WILL PUSH ACROSS THE REGION THROUGH SUNDAY. GFS IS MORE
BULLISH THAN THE ECMWF...BUT BOTH MODELS BRING THE POTENTIAL FOR
PLOWABLE ACCUMULATION BY SUNDAY EVENING. POPS WERE ALMOST BROUGHT
INTO THE LIKELY CATEGORY...BUT KEPT THEM JUST BELOW 55 WITH SOME
PRETTY LARGE MODEL DIFFERENCES FOR THIS TIME RANGE...NAMELY THE
LOW TRACK WHICH IS ALMOST 500 MILES BETWEEN THE 06Z GFS AND 00Z
ECMWF.
THE SECOND SYSTEM ARRIVES EARLY NEXT WEEK. WITH THE SOUTHERN RIDGE
A BIT FURTHER EAST...THIS ONE COULD WRAP UP INTO A MORE
SIGNIFICANT SYSTEM A LA THE ECMWF. STILL LARGE DIFFERENCES AMONGST
THE GUIDANCE...CERTAINLY NOT UNEXPECTED GIVEN IT IS 7 DAYS OUT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY)
ISSUED AT 417 AM CST WED FEB 10 2016
VFR CONDITIONS THROUGHOUT AT ALL LOCATIONS EXCEPT FOR KRWF. FORECAST
SOUNDINGS FOR THIS LOCATION SHOW LIGHT SNOW POSSIBLE THIS MORNING.
FOR THE REST OF THE SITES...WINDS WILL BE LIGHT AND VARIABLE WITH
SOME MID LEVEL CLOUDS.
KMSP...VFR CONDITIONS THROUGHOUT. THIS MORNINGS SNOW WILL BE WELL
TO THE WEST OF MSP...WINDS SHOULD PICK UP AN EASTERLY COMPONENT
THROUGH THE MORNING AND EARLY AFTERNOON...AND WILL THEN BE LIGHT
AND VARIABLE THIS EVENING AND OVERNIGHT.
/OUTLOOK FOR KMSP/
THU...VFR. WIND NW AT 5-10KT BECOMING W.
FRI...VFR. WIND NW AT 10G20 KT.
SAT...VFR. WIND NNE AT 5 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
SHORT TERM...JRB
LONG TERM...BORGHOFF
AVIATION...JRB
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
859 PM CST THU FEB 11 2016
.UPDATE:
Issued at 859 PM CST Thu Feb 11 2016
Have made some minor adjustments to snowfall based on this
evening`s radar and satellite trends. Water vapor is showing a mid
level vort max currently dropping southeastward out of eastern
Nebraska into northwestern Missouri with a deformation axis
extending from northeast Missouri into west central Iowa. It is
taking some time for the snow to overtake the dry air in the low
levels, so only reports of snow so far in the CWA have flurries
over northeast Missouri. Do think the accumulating snow currently
over Iowa will move into northeast Missouri and west central
Illinois shortly. It still appears the the intensity of the
snowfall will weaken as it moves southeast per the recent runs of
the the RAP. Do not expect much accumulation of snow as far south
at I-70 before midnight...so have shifted the 1 inch totals
slightly northward into northeast Missouri and west central
Illinois with lesser amounts to the south. It still will be a cold
night, so even light snowfall amounts could impact travel. Also
watching second area of radar returns over western Missouri which
has only one or two reports of light snow with it. Any snow
accumulations with it should be light as it moves across the
southern CWA over the next few hours.
Britt
&&
.SHORT TERM: (Through Late Tonight)
Issued at 1230 PM CST Thu Feb 11 2016
A northwest flow shortwave now dropping southeastward into western
SD will move quickly through our area tonight. Light snow will
spread southeastward into northeast MO early this evening, then
through the St Louis metro area around midnight. Still looking like
a quick shot of dry, powdery snow with most places picking up to 1
inch of accumulation, but there may be a narrow band of 1-2 inches
extending from near IRK southeast through the St Louis metro area.
Latest NAM and HRRR model runs have the band a little further west
than previous model runs. Most of the accumulating snow should
shift southeast of our forecast area by 12Z Friday. Low
temperatures will be similar to the previous night, and around 5
degrees below normal.
GKS
.LONG TERM: (Friday through Next Thursday)
Issued at 316 PM CST Thu Feb 11 2016
A strong cold front will move southeastward through our forecast
area on Friday with strengthening winds as the surface pressure
gradient tightens as a strong 1040-1045 mb surface high builds
southeastward into the area from the northern Plains behind the cold
front. Temperatures may begin to fall in northeast MO behind the
front already by Friday afternoon. Much colder temperatures are
expected for Friday night and Saturday with wind chills down to
around 10 below zero late Friday night and early Saturday morning
across northeast MO and west central IL. Snow should spread
southeastward into at least northeast MO and west central IL late
Saturday night as low-mid level warm air advection increases ahead
of an approaching northern stream shortwave. It still appears that
the ECMWF model is a little too quick bringing precipitation into
our forecast area already be Saturday afternoon and evening with an
initially very dry boundary layer on the backside of the surface
ridge. The better chance of precipitation should occur on Sunday as
a southwesterly low level jet brings increasing low level moisture
into our area ahead of the shortwave. It is too early to pin down
exact snow totals, but it initially appears that 2-4 inches is
possible across northeast MO and west central IL with lesser amounts
of 1-2 inches further south for Saturday night and Sunday. Another
round of precipitation is expected, mainly on Monday, as a southern
stream shortwave and associated surface low pass south of our area.
This precipitation should be confined mainly to southeast MO and
southwest IL. With temperatures trending up as we head into the
next work week there may also be precipitation type issues with a
mix of snow, sleet and rain possible. Will keep the rest of the
forecast dry with a warming trend, although the ECMWF model does
depict some weaker weather systems bringing a brief period or two of
light QPF to our area. The GFS model is dry for the remainder of
the period after Monday with a dry cold frontal passage on Tuesday
afternoon and evening. Both the GFS and ECMWF models depict a warm
weather pattern by Thursday with upper level ridging over the region
along with strong s-swly low level winds likely leading to well
above normal temperatures.
GKS
&&
.AVIATION: (For the 00z TAFs through 00z Friday Evening)
Issued at 536 PM CST Thu Feb 11 2016
Snow over Iowa will move southeast this evening into the terminals
bringing MVFR and IFR visibilities during a 4-6 hour window.
Snowfall will be lightest at KCOU where only a dusting is expected
compared to KUIN and the St. Louis area terminals where 1-1.5
inches may occur by the time the snow ends. Then low MVFR or IFR
ceilings will linger into the late morning hours on Friday before
drier air allows for VFR conditions to prevail by afternoon.
Specifics for KSTL: Snow is expected to move into the terminal
later this evening causing visibilities to fall into the IFR range
through early morning before it ends. Accumulations should be
around 1 inch and temperatures in the lower 20s late tonight. Then
low MVFR or IFR ceilings will linger into the late morning hours
on Friday before drier air allows for VFR conditions to prevail by
afternoon.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
558 PM CST THU FEB 11 2016
.SHORT TERM: (Through Late Tonight)
Issued at 1230 PM CST Thu Feb 11 2016
A northwest flow shortwave now dropping southeastward into western
SD will move quickly through our area tonight. Light snow will
spread southeastward into northeast MO early this evening, then
through the St Louis metro area around midnight. Still looking like
a quick shot of dry, powdery snow with most places picking up to 1
inch of accumulation, but there may be a narrow band of 1-2 inches
extending from near IRK southeast through the St Louis metro area.
Latest NAM and HRRR model runs have the band a little further west
than previous model runs. Most of the accumulating snow should
shift southeast of our forecast area by 12Z Friday. Low
temperatures will be similar to the previous night, and around 5
degrees below normal.
GKS
.LONG TERM: (Friday through Next Thursday)
Issued at 316 PM CST Thu Feb 11 2016
A strong cold front will move southeastward through our forecast
area on Friday with strengthening winds as the surface pressure
gradient tightens as a strong 1040-1045 mb surface high builds
southeastward into the area from the northern Plains behind the cold
front. Temperatures may begin to fall in northeast MO behind the
front already by Friday afternoon. Much colder temperatures are
expected for Friday night and Saturday with wind chills down to
around 10 below zero late Friday night and early Saturday morning
across northeast MO and west central IL. Snow should spread
southeastward into at least northeast MO and west central IL late
Saturday night as low-mid level warm air advection increases ahead
of an approaching northern stream shortwave. It still appears that
the ECMWF model is a little too quick bringing precipitation into
our forecast area already be Saturday afternoon and evening with an
initially very dry boundary layer on the backside of the surface
ridge. The better chance of precipitation should occur on Sunday as
a southwesterly low level jet brings increasing low level moisture
into our area ahead of the shortwave. It is too early to pin down
exact snow totals, but it initially appears that 2-4 inches is
possible across northeast MO and west central IL with lesser amounts
of 1-2 inches further south for Saturday night and Sunday. Another
round of precipitation is expected, mainly on Monday, as a southern
stream shortwave and associated surface low pass south of our area.
This precipitation should be confined mainly to southeast MO and
southwest IL. With temperatures trending up as we head into the
next work week there may also be precipitation type issues with a
mix of snow, sleet and rain possible. Will keep the rest of the
forecast dry with a warming trend, although the ECMWF model does
depict some weaker weather systems bringing a brief period or two of
light QPF to our area. The GFS model is dry for the remainder of
the period after Monday with a dry cold frontal passage on Tuesday
afternoon and evening. Both the GFS and ECMWF models depict a warm
weather pattern by Thursday with upper level ridging over the region
along with strong s-swly low level winds likely leading to well
above normal temperatures.
GKS
&&
.AVIATION: (For the 00z TAFs through 00z Friday Evening)
Issued at 536 PM CST Thu Feb 11 2016
Snow over Iowa will move southeast this evening into the terminals
bringing MVFR and IFR visibilities during a 4-6 hour window.
Snowfall will be lightest at KCOU where only a dusting is expected
compared to KUIN and the St. Louis area terminals where 1-1.5
inches may occur by the time the snow ends. Then low MVFR or IFR
ceilings will linger into the late morning hours on Friday before
drier air allows for VFR conditions to prevail by afternoon.
Specifics for KSTL: Snow is expected to move into the terminal
later this evening causing visibilities to fall into the IFR range
through early morning before it ends. Accumulations should be
around 1 inch and temperatures in the lower 20s late tonight. Then
low MVFR or IFR ceilings will linger into the late morning hours
on Friday before drier air allows for VFR conditions to prevail by
afternoon.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1140 PM CST TUE FEB 9 2016
.UPDATE:
Issued at 839 PM CST Tue Feb 9 2016
Radar is showing a few light snow showers currently moving
through the metro area likely just ahead of a weak vort max seen
on water vapor imagery. Have added isolated flurries to the
southern and eastern parts of the CWA for the mid and late evening
hours. Otherwise there will be some clearing tonight before
additional cloudiness moves back into the area by daybreak.
Otherwise going lows look on track based on temperature trends.
Britt
&&
.SHORT TERM: (Through Late Tonight)
Issued at 345 PM CST Tue Feb 9 2016
Scattered flurries will continue for the rest of the afternoon under
the strato-cu deck. There is a clearing slot running down the west
side of the Mississippi River down almost to the Missouri River. The
clouds should continue to break up...although RAP and NAM soundings
show plenty of low level moisture trapped under an inversion into
the evening. Think most of the area should be clear of the low
clouds by 06Z...though south central Illinois counties will likely
stay under the clouds into Wednesday morning. Cold advection on
northwest flow will continue tonight into early Wednesday. Think
guidance temperatures in the single digits to mid teens look good
for lows tonight.
Focus turns to storm system developing on Wednesday. This look to
be a purely warm advection/frontogenesis snow. GFS, ECMWF and NAM
are showing some pretty high values of warm advection...between 30
to 50 degrees C/12hr. Forecast soundings show the moist layer
extending up into the dendritic growth zone with a decent amount of
lift through that layer as well. Looks like the snow will hold off
until mid-late afternoon. Due to the cold atmosphere and lift in
the best snow-growth zone, expect this will be a fluffy snow which
will accumulate pretty quickly...especially since highs will stay
well below freezing.
Carney
.LONG TERM: (Wednesday through Next Tuesday)
Issued at 345 PM CST Tue Feb 9 2016
Model guidance continues to improve its consensus for the track and
impact on the storm system expected to be ongoing early Wednesday
evening. The consensus track for max QPF stretches from north-
central MO thru the southwestern half of the STL metro area and
towards Cape Girardeau, MO. The WAA associated with this event is
expected to be intense and will probably result in rapid onset and
development which, again, should be ongoing by sundown Wednesday
evening. WAA remains intense thru much of Wednesday evening with
lift continuing well into the overnight hours, and for this reason,
will keep a mention of pcpn thru the nighttime hours with this
package. A fairly broad stripe of up to 1" of new snow accum is now
looking possible with this system, with near 2" potential in its
core/peak QPF track. If the WAA continues to be advertised as
intense with this system, these snow amounts, especially in the core
track, will probably need to be bumped up further due to high
anticipated snow to liquid ratios, when light winds are taken into
account from the surface RIDGE being over our region and a cold low-
mid level column.
Another system, of a more classic clipper variety, may impact our
region on late Thursday night into Friday, but the track for this
continues to be more to the northeast thru southern IA into central
IL, with only a modest mention of flurries or low PoPs justified at
this time.
Otherwise, a prolonged period of below average temps is forecast
from now thru the upcoming weekend, with very little moderation
expected in temps on Friday before the next shot of Arctic air
descends on our region for the weekend. Only by early next week
does the persistent RIDGE over the western CONUS begin to translate
eastward and could mean a return to average to even above average
temps at some point next week.
It is near this transition period Sunday-Monday that another system
is expected to impact our region. The GFS has finally come onboard
with the more consistent EC and GEM solutions but the nature of this
system is far from settled, with its initial onset possibly as early
as Saturday night and it may be completely done by Monday now. This
earlier timing would certainly favor an all snow event, with more
average temps for mid-February set to return on the heels of this
event. With the main storm still well over the north Pacific, there
is much that can go wrong or change and something to stay tuned for.
But as it stands now, could see widespread advisory criteria
snowfall.
TES
&&
.AVIATION: (For the 06z TAFs through 06z Wednesday Night)
Issued at 1139 PM CST Tue Feb 9 2016
High MVFR ceilings are KUIN are expected to move out of the
terminal shortly. Some brief VFR snow showers are possible early
in the TAF period at the St. Louis area terminals.
Otherwise...expect mainly dry and VFR conditions until midday
Wednesday when snow will move into the terminals from the north.
Then visibilities will lower to MVFR and IFR during the afternoon
and evening hours as the snow begins to accumulate up to an inch.
Specifics for KSTL: Flurries are possible the first hour or two of
the TAF period. Otherwise expect dry and VFR conditions until snow
moves back into the terminal during the later afternoon hours on
Wednesday. Visibilities will lower to MVFR and IFR during the
afternoon and evening hours before the snow ends.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
523 PM CST THU FEB 11 2016
.SHORT TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 340 PM CST THU FEB 11 2016
BAND OF WAA/ISENTROPIC LIFT -SN IN ADVANCE OF POTENT UPPER-LEVEL
PV ANOMALY CURRENTLY OVER CNTR SD HAS GENERALLY MOVD E OF THE FA
EARLY THIS AFTN. THIS ANOMALY WILL TRACK SEWD THIS EVENING ALONG
THE STRG MID-LVL THRML GRADIENT ALREADY IN PLACE OVER THE CTRL
PLAINS. THIS WILL LIKELY LEAD TO ADDITIONAL BAND OF -SN OVER THE
ERN HALF OF THE CWA THIS EVENING TRACKING SEWD. AGAIN NOT MUCH IN
THE WAY OF ACCUMULATION IS EXPECTED WITHIN THIS BAND...BUT WILL
INCLUDE UP TO A HALF INCH IN W-CNTRL IA. ARCTIC HIGH PRESSURE
CURRENTLY OVER NRN SASK WILL DVDLP SWD INTO THE AREA DURING THE
DAY ON FRIDAY AND WE WILL GENERALLY SEE STEADY OR SLOWLY FALLING
TMPS WITH THE LOW- LEVEL CAA ON FRI. DID INCREASE LOWS ON FRI
NIGHT AS WE ARE EXPECTED AN INCREASE IN MID AND HIGH LEVEL CLOUDS
IN ADVANCE OF A BAND OF WAA/ISENTROPIC LIFT AHEAD OF THE NEXT
SYSTEM SET FOR SAT NIGHT SUN. WILL INCLUDE SOME -SN CHCS IN THE
NRN CWA DURING THE DAY ON SAT...MAYBE MAKING IT SEWD INTO W-CNTRL
IA IN THE AFTN BUT ANY PRECIP WILL BE FIGHTING SOME VERY DRY AIR.
LARGE-SCALE SUPPORT FOR ASCENT INCREASES ON SAT NIGHT...BUT BEST
JUXTAPOSITION OF WEAKER STATIC STABILITY...FRONTOGENESIS AND Q-G
FORCING OCCUR TO THE NORTH AND EAST OF OUR FA WHERE MOST OF THE SN
SHLD FALL. WILL INCLUDE SOME LO CHC POPS OVER THE NRN ERN
CWA...BUT EXPECT THE BAND TO BE MAINLY OUT OF OUR AREA. THIS
TREND CONTS INTO SUN AS THE BEST 700-400 MB DCPVA MOVES THROUGH
THE CWA...BUT WE LOSE SOME MID-LVL SATURATION AND AGAIN THE BEST
SN LOOKS TO BE EAST OF OUR AREA. DID INCREASE HIGHS SEVERAL CAT ON
SUN AND MIGHT NOT BE WARM ENOUGH AS OUR LOW-LEVEL FLOW TURNS
SOUTHWEST AND WE MAY SEE SOME SUN IN THE AFTN.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 340 PM CST THU FEB 11 2016
LARGE-SCALE PATTERN CHANGE STILL LOOKS LIKELY IN THE EXTENDED
RANGE OF THE FORECAST...BUT JUST HOW FAR E THE MID-LVL RIDGE
FLATTENS IS STILL IN DOUBT. IT DOES LOOK LIKE WE WILL SEE SOME
WARMING...BUT MODELS DIFFER ON THE TIMING OF CONTD WEAK WAVES IN
THE NORTHWEST FLOW AND HOW SIG ANY CAA WILL BE. GIVEN THE
UNCERTAINTY OF THE WARMING WILL TREND WILL TREND A BIT
COOLER WITH TMPS. IT DOES GENERALLY LOOK DRY THROUGH THE PERIOD.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 520 PM CST THU FEB 11 2016
A SURFACE LOW ANALYZED W OF ONL AS OF 22Z WILL DEVELOP SEWD INTO
NERN KS AFTER 12/06Z. PREVAILING S OR SE WINDS AT THE TAF SITES
WILL BECOME NLY WITH THE PASSAGE OF THIS LOW PRESSURE...WITH
PREDOMINANTLY MVFR CIGS TONIGHT INTO AT LEAST FRIDAY MORNING.
LATEST HRRR GUIDANCE SUGGESTS THAT A SMALL AREA OF LIGHT SNOW
PRESENTLY W OF SUX WILL PROGRESS SEWD AND POTENTIALLY IMPACT KOMA
IN THE 12/02-04Z TIMEFRAME...TEMPORARILY LOWERING VISIBILITIES.
OTHERWISE...WE SHOULD BEGIN TO SEE DRIER LOW-LEVEL AIR BEGIN TO
WORK ITS WAY SWWD ACROSS THE AREA LATE FRIDAY MORNING INTO
AFTERNOON WITH VFR CONDITIONS BECOMING PREDOMINANT.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...
LONG TERM...
AVIATION...MEAD
AREA FORECAST DISCUSSION
NWS HASTINGS NE
405 PM CST WED FEB 10 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 342 PM CST WED FEB 10 2016
AFTER A SEASONABLY NICE AFTERNOON...EXPECT TEMPERATURES TO
RAPIDLY FALL BACK BELOW FREEZING THIS EVENING AS THE SUN GOES
DOWN...WITH CLOUDS BEGINNING TO ROLL BACK IN ACROSS THE LOCAL
AREA FROM THE NORTHEAST OVERNIGHT. COULD SEE SOME FOG DEVELOPMENT
ON THE LEADING EDGE OF THIS STRATUS...AND OPTED TO INTRODUCE THIS
INTO THE FORECAST AFTER ABOUT MIDNIGHT TONIGHT. WHILE THE BEST
CHANCE FOR THE MORE DENSE FOG IS WEST OF THE LOCAL AREA...THE
LATEST RUN OF THE HRRR IS INDICATING THIS MORE DENSE AREA OF FOG
COULD AT LEAST CREEP IN ON OUR WESTERN COUNTIES TOWARDS
DAYBREAK...AND THIS WILL BE SOMETHING FOR THE EVENING SHIFT TO
MONITOR AS NEW MODEL DATA COMES IN.
OTHERWISE...EXPECT LITTLE SHIFT IN THE OVERALL SYNOPTIC PATTERN
THROUGH THE SHORT TERM PERIODS AS NORTHWESTERLY FLOW ALOFT WILL
CONTINUE WITH A WEAK UPPER LEVEL WAVE MAKING ITS WAY OVER THE TOP
OF THE UPPER LEVEL RIDGE AND TOWARDS THE LOCAL AREA TOMORROW
AFTERNOON. AS THE LOW LEVEL FLOW TURNS MORE EASTERLY AND THEN
SOUTHEASTERLY OVERNIGHT...EXPECT THE FRONTAL BOUNDARY TO OUR EAST
TO INCH BACK ACROSS THE LOCAL AREA...BRINGING SIGNIFICANT LOW
LEVEL STRATUS AND COOLER TEMPERATURES BACK TOWARDS THE REGION
TOMORROW...WITH A MOSTLY CLOUDY DAY AND MORE SEASONAL TEMPERATURES
EXPECTED FOR TOMORROW AFTERNOON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 342 PM CST WED FEB 10 2016
MODELS ARE IN GOOD AGREEMENT AT THE START OF THE LONG TERM PERIOD
THURSDAY NIGHT LOOKING AT THE OVERALL PICTURE...UPPER LEVEL NWRLY
FLOW EXPECTED TO REMAIN IN PLACE ACROSS THE REGION. LOW PRESSURE
OVER THE HUDSON BAY AREA KEEPS THE ERN CONUS UNDER BROAD
TROUGHING...WHILE A RIDGE OF HIGH PRESSURE EXTENDS NORTH THROUGH THE
ROCKIES. AT THIS POINT...KEPT THE FORECAST DRY THURS NIGHT AND
FRIDAY...AS MODELS CONTINUE TO KEEP THE BETTER PRECIP CHANCES
ASSOCIATED WITH AN UPPER LEVEL JET STREAK JUST OFF TO THE N/NE OF
THE CWA. THE MAIN STORY THROUGH FRIDAY LIES WITH THE PASSAGE OF A
COLD FRONT...BEING PUSHED SOUTH BY SHORTWAVE ENERGY SWINGING THROUGH
TO THE N/NE. WHILE THE SFC PATTERN STARTS THE PERIOD OUT FAIRLY
RELAXED...THIS FRONT WITH USHER IN NRLY WINDS BY SUNRISE
FRIDAY...GRADUALLY TURNING MORE NERLY THROUGH THE DAY. COLDER AIR
STARTS TO ADVECT INTO THE CWA...AND DID LOWER FORECAST HIGHS FOR
FRIDAY...WITH NEAR 30 NOW IN THE NORTHEAST TO NEAR 40 IN THE SW.
CONFIDENCE IN THIS WEEKEND...MAINLY REGARDING PRECIP
CHANCES/LACK OF...IS NOT HIGH. OVERALL UPPER LEVEL REMAIN LOOKS TO
REMAIN NORTHWESTERLY...BUT THERE IS BETTER POTENTIAL FOR THE CWA TO
BE AFFECTED BY SHORTWAVE ENERGY MOVING THROUGH THE MAIN FLOW. LATE
FRIDAY NIGHT INTO SATURDAY MORNING IS THE FIRST SHOT OF THIS ENERGY
MOVING THROUGH...WITH MODELS ALSO SHOWING THE CWA SITTING ON THE ERN
EDGE OF A 25-30KT LLJ SITTING OVER THE HIGH PLAINS. MODELS HINTING
AT THE POTENTIAL FOR SOME LIGHT PRECIPITATION AFFECTING MAINLY WRN
AND NRN PORTIONS OF THE CWA...WITH FORECAST SOUNDINGS DIFFERING SOME
WITH THE OVERALL THICKNESS OF THE SATURATED LAYER...LEAVING THE
QUESTION WHETHER THERE WOULD BE ANYTHING MEASURABLE...OR IF IT WOULD BE MORE
FZDZ OR FLURRIES. HAVE A 20 POP/SNOW GOING AS WELL AS A SLGT CHANCE
FOR FZDZ. ONLY KEPT THE MENTION GOING THROUGH THE FIRST HALF OF THE
DAY...THOUGH IF YOU BELIEVE THE NAM QPF FIELDS THERE WOULD BE
SOMETHING AROUND ALL DAY SATURDAY. AS FAR AS TEMPERATURES
GO...SATURDAY STILL FORECAST TO BE THE COLDEST DAY OF THE LONG TERM
PERIOD. BY SUNRISE SATURDAY...SFC HIGH PRESSURE IS EXPECTED TO BE
LOCATED OVER NERN IA...WITH ERN PORTIONS OF THE CWA NOT TOO FAR AWAY
FROM DOUBLE DIGIT BELOW ZERO TEMPS AT 850MB. EVEN WITH THE BRUNT OF
THE COLDEST AIR OFF TO OUR EAST...FORECAST HIGHS CURRENTLY RANGE
FROM NEAR 20 IN THE NORTHEAST TO LOWER 30S IN THE SW. LOOKING TO
SUNDAY...THE FORECAST IS DRY...BUT AS MENTIONED ABOVE CONFIDENCE IS
NOT HIGH. MODELS SHOW THE POTENTIAL FOR 1 /PERHAPS 2/ WEAK WAVES TO
MOVE THROUGH THE PLAINS THROUGH SUNDAY NIGHT...JUST SOME DIFFERENCES
IN LOCATION. WILL SEE HOW THINGS TREND BEFORE INSERTING POPS.
EXPECTING TO SEE REBOUNDING TEMPS FOR SUNDAY AS THAT COLDER AIR
PUSHES EAST AND WARMER TEMPS START TO BUILD IN...WITH 40S CURRENTLY
FORECAST FOR MOST OF THE CWA.
THROUGH THE FIRST HALF OF THE NEXT WORK WEEK...THE FORECAST REMAINS
DRY...WITH MODELS IN PRETTY GOOD AGREEMENT SHOWING BROAD UPPER LEVEL
RIDGING TAKING OVER THE WRN CONUS AND GRADUALLY BUILDING EAST. NICE
WARM UP CURRENTLY GOING IN THE FORECAST...WITH 50S FORECAST FOR
TUE/WED.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1143 AM CST WED FEB 10 2016
VFR CONDITIONS ARE EXPECTED THROUGH THE MID EVENING HOURS AS
MAINLY CLOUD FREE SKIES AND LIGHT WESTERLY FLOW CONTINUES. WITH
SIGNIFICANT SNOW MELT THIS AFTERNOON AND CLEAR SKIES TO START THE
EVENING...EXPECT THE POSSIBILITY OF SOME FOG FORMATION DURING THE
OVERNIGHT HOURS AS A RESULT. WHILE CONFIDENCE WAS NOT HIGH ENOUGH
TO INCLUDE LIFR CONDITIONS AS SUGGESTED BY SOME OF THE
GUIDANCE...DID INCLUDE SOME MVFR VSBYS AND IFR CIGS AFT 11/06Z.
THEREAFTER...EXPECT MVFR STRATUS TO ADVECT IN FROM THE NORTH EVEN
IF LOWER CIGS/VSBYS ARE NOT REALIZED IN AREAS OF FOG AHEAD OF THIS
STRATUS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...ROSSI
LONG TERM...ADP
AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1010 AM EST WED FEB 10 2016
.SYNOPSIS...
LOW PRESSURE OVER LAKE ONTARIO WILL SLIDE EASTWARD INTO NEW
ENGLAND TODAY. IN THE WAKE OF THIS SYSTEM...A PROGRESSIVELY COLDER
ARCTIC AIRMASS WILL OVERSPREAD THE REGION THROUGH THE
WEEKEND...WHILE GENERATING ACCUMULATING LAKE SNOWS TO THE LEE OF
THE GREAT LAKES. THE MOST FRIGID CONDITIONS ARE EXPECTED ON
SATURDAY...WHEN HIGHS WILL LIKELY STRUGGLE TO CLIMB MUCH ABOVE
ZERO...AND WIND CHILLS WILL BE AT DANGEROUSLY LOW LEVELS.
&&
.NEAR TERM /THROUGH TONIGHT/...
MORNING UPDATE...UPGRADED NIAGARA...ORLEANS AND MONROE COUNTIES
TO A LAKE EFFECT SNOW WARNING AND SHIFTED THE START TIME TO 9AM
BASED ON CURRENT RADAR AND SATELLITE TRENDS. KBUF RADAR IS SHOWING
A WELL ORGANIZED SNOW BAND RIDING THE SOUTHERN LAKE ONTARIO
SHORELINE FROM YOUNGSTOWN EAST TO WEBSTER STAYING JUST NORTH OF
DOWNTOWN ROCHESTER. THE KING CITY CANADIAN RADAR SHOWS AN UPSTREAM
CONNECTION TO GEORGIAN BAY WHICH IS ENHANCING THE LAKE BAND OVER
THE WESTERN LAKE ONTARIO LAKESHORE. KBUF RADAR ESTIMATED SNOW
RATES ARE RANGING FROM 1 TO 2 INCHES PER HOUR WITHIN THE BAND
WHICH HAS BEEN ENHANCED BY A PASSING MID-LEVEL SHORTWAVE AND 700MB
MOISTURE PLUME. THIS ALONE HAS INCREASED CONFIDENCE TO UPGRADE TO
A WARNING WITH MESOSCALE GUIDANCE SUCH AS THE LATEST HRRR AND RGEM
MODELS SUGGESTING THE BAND COULD PERSIST IN PLACE INTO THE
AFTERNOON HOURS WHILE THE CORE OF HEAVIEST SNOW SLOWLY SHIFTS
TOWARD THE SOUTHEAST LAKES SHORE. SNOW TOTALS WITHIN THIS NEWLY
UPGRADED WARNING HAVE BEEN INCREASED TO A RANGE OF 7 TO 15 INCHES
RANGING FROM TODAY INTO THURSDAY AFTERNOON.
OUTSIDE OF THE LATEST WARNING UPGRADE...THE FORECAST REMAINS
UNCHANGED FROM THE EARLY MORNING HOURS. LOW PRESSURE OVER EASTERN
LAKE ONTARIO WILL DRIFT EASTWARD INTO NEW ENGLAND TODAY...WITH A
PROGRESSIVELY COLDER ARCTIC-SOURCED AIRMASS OVERSPREADING OUR REGION
TODAY AND TONIGHT. OUTSIDE OF AREAS OF OROGRAPHICALLY-INDUCED AND
LAKE EFFECT SNOWS EAST AND SOUTHEAST OF THE LAKES WITHIN THE COLDER
AIRMASS...THIS SYSTEM IS BRINGING CLOUDY SKIES AND A GENERAL LIGHT
SNOWFALL OF A FEW INCHES TO THE REGION TODAY INTO TONIGHT...WHILE
ALSO CONTINUING THE TREND TOWARD COLDER TEMPERATURES.
REGARDING THE AREAS OF ENHANCED SNOWFALL MENTIONED ABOVE...
OFF LAKE ERIE...A GENERAL WESTERLY FLOW ON THE BACKSIDE OF THE
DEPARTING LOW TODAY WILL VEER MORE WEST-NORTHWESTERLY TONIGHT
FOLLOWING THE PASSAGE OF A NOTEWORTHY MID/UPPER LEVEL SHORTWAVE.
UNDER THIS FLOW REGIME...THE STEADIEST LAKE AND TERRAIN-ENHANCED
SNOWS WILL TEND TO FOCUS MOST ACROSS THE CHAUTAUQUA RIDGE REGION
OF SOUTHERN ERIE/CHAUTAUQUA/CATTARAUGUS COUNTIES THROUGH THE NEAR
TERM PERIOD...WITH THE ACTIVITY BECOMING INCREASINGLY LAKE-DRIVEN
OVER TIME AS OUR AIRMASS GROWS COLDER. THE HEAVIEST AND MOST
PERSISTENT SNOWS IN THIS REGION ARE FALLING THIS MORNING THROUGH
TONIGHT...WITH THE MORE SIGNIFICANT SNOWS TONIGHT TIED TO THE
PASSAGE OF THE SHORTWAVE AND THE SUBSEQUENT POTENTIAL DEVELOPMENT OF
AN UPSTREAM CONNECTION TO LAKE HURON LATER ON TONIGHT. WITH LAKE
EQLS OF 8-10 KFT IN PLACE AND FAVORABLE MOISTURE LYING BELOW
THAT...THE STAGE APPEARS SET FOR WARNING-CRITERIA SNOWFALL AMOUNTS
ACROSS THE ABOVE MENTIONED REGION BETWEEN TODAY AND THURSDAY. SOME
OF THE HEAVIER SNOWS WILL ALSO CONTINUE TO OCCASIONALLY VENTURE INTO
WESTERN WYOMING COUNTY AT TIMES THROUGH AT LEAST THIS
MORNING...WHERE A LAKE EFFECT SNOW ADVISORY REMAINS IN EFFECT.
MEANWHILE OFF OF LAKE ONTARIO...LAKE ENHANCED SNOWS ARE NOW TAKING
SHAPE SOUTH AND EAST OF THE LAKE ON A WESTERLY FLOW. THE CORE OF
THESE SNOWS WILL SHIFT EVENTUALLY INTO THE WAYNE-NORTHERN CAYUGA-
SOUTHERN OSWEGO COUNTY CORRIDOR THIS AFTERNOON AND EVENING AS THE
LOW LEVEL FLOW BECOMES BETTER ALIGNED OUT OF THE WEST-NORTHWEST
BEFORE SETTLING EVEN A LITTLE FURTHER SOUTHWARD LATER TONIGHT
FOLLOWING THE PASSAGE OF THE AFOREMENTIONED SHORTWAVE. AS WITH THE
LAKE ERIE ACTIVITY...A PRETTY FAVORABLE ENVIRONMENT IN PLACE WITH
LAKE EQLS OF 8-10 KFT PRESENT AND SUFFICIENT MOISTURE LYING BELOW
THAT TO RESULT IN A DECENT POTENTIAL FOR WARNING-CRITERIA SNOWFALL
AMOUNTS WHERE THE SNOWS WILL BE MOST PERSISTENT TODAY THROUGH
THURSDAY...WHICH IN THIS CASE APPEARS TO BE THE NORTHEASTERN WAYNE-
SOUTHERN OSWEGO COUNTY CORRIDOR WHERE LAKE EFFECT SNOW WARNINGS ARE
IN EFFECT. MEANWHILE NORTH OF THIS WARNING AREA... LAKE EFFECT SNOW
ADVISORIES ARE IN EFFECT FOR THE TUG HILL REGION WHERE LESSER BUT
STILL ADVISORY-WORTHY AMOUNTS APPEAR LIKELY BETWEEN TODAY AND
THURSDAY.
AS FOR TEMPERATURES...EXPECT THESE TO PEAK IN THE UPPER 20S TO
LOWER 30S BETWEEN THIS MORNING AND EARLY THIS AFTERNOON...THEN
STEADILY DROP INTO THE 10-15 RANGE ACROSS MUCH OF THE AREA BETWEEN
THE REMAINDER OF THIS AFTERNOON AND TONIGHT. BY LATE
TONIGHT...READINGS MAY EVEN FALL INTO THE UPPER SINGLE DIGITS
ACROSS PORTIONS OF THE SOUTHERN TIER AND NORTH COUNTRY.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
ON THURSDAY THE SURFACE LOW WILL MOVE EAST INTO THE CANADIAN
MARITIMES WITH THE MID LEVEL TROUGH CROSSING THE LOWER LAKES REGION.
ASCENT AND DEEPER MOISTURE ASSOCIATED WITH THE MID LEVEL TROUGH WILL
PRODUCE A FEW SCATTERED SNOW SHOWERS OUTSIDE OF LAKE EFFECT AREAS...
ESPECIALLY EAST OF LAKE ONTARIO WHERE FORCING WILL BE STRONGEST. THE
MAIN FOCUS THURSDAY AND THURSDAY NIGHT WILL BE WITH THE ONGOING LAKE
EFFECT SNOW SOUTHEAST OF THE LAKES.
OFF LAKE ERIE...
LAKE INDUCED INSTABILITY REMAINS STRONG THROUGH THE PERIOD WITH
EQUILIBRIUM LEVELS AROUND 10K FEET. BOUNDARY LAYER FLOW WILL
CONTINUE TO BE NORTHWEST ON THURSDAY...WHICH WILL LIMIT THE FETCH
ACROSS LAKE ERIE BUT ALSO PROVIDE FAVORABLE UPSLOPE FLOW ALONG THE
CHAUTAUQUA RIDGE. MESOSCALE MODEL GUIDANCE CONTINUES TO SUGGEST AN
UPSTREAM CONNECTION TO LAKE HURON ESPECIALLY DURING THE FIRST HALF
OF THURSDAY. THIS WILL LIKELY ENHANCE SNOWFALL RATES ACROSS PORTIONS
OF CHAUTAUQUA COUNTY...MOST LIKELY THE FAR SOUTHWEST CORNER OF THE
COUNTY NEAR FINDLAY LAKE GIVEN THE FLOW DIRECTION. THIS UPSTREAM
CONNECTION WILL END LATER THURSDAY AFTERNOON AS BOUNDARY LAYER FLOW
BACKS ACROSS SOUTHERN LAKE HURON. THE END OF THE UPSTREAM CONNECTION
AND ALSO A WEAK SURFACE RIDGE BRIEFLY BUILDING OVER LAKE ERIE SHOULD
WEAKEN THE LAKE ERIE LAKE EFFECT LATER THURSDAY AFTERNOON AND
EVENING.
EXPECT ADDITIONAL ACCUMULATIONS OF 3-6 INCHES ON THURSDAY IN
PERSISTENT BANDS ACROSS THE WESTERN SOUTHERN TIER...WITH THE HIGHER
AMOUNTS FOCUSED ON THE UPSLOPE AREAS OF THE CHAUTAUQUA RIDGE AND
ALSO WHERE THE LAKE HURON CONNECTION FORMS. THIS WILL BRING STORM
TOTALS FROM LATE TUESDAY EVENING THROUGH LATE THURSDAY AFTERNOON
INTO THE 12-18 INCH RANGE IN THE MOST PERSISTENT BANDS...MAINLY IN A
RELATIVELY SMALL AREA OF UPSLOPE FLOW JUST INLAND FROM THE
LAKESHORE.
LATER THURSDAY NIGHT AND FRIDAY BOUNDARY LAYER FLOW WILL BACK TO THE
WEST AND EVENTUALLY WSW AS A SURFACE LOW RACES EAST ACROSS SOUTHERN
ONTARIO IN ADVANCE OF THE ARCTIC FRONT. THE BACKING WINDS WILL ALLOW
LAKE EFFECT SNOW TO RE-ORGANIZE LATE THURSDAY NIGHT AS FETCH
INCREASES ACROSS THE LAKE. INSTABILITY REMAINS STRONG THROUGH FRIDAY
WITH EQUILIBRIUM LEVELS AROUND 10K FEET...ALTHOUGH THE AIRMASS MAY
DRY OUT IN THE TOP OF THAT LAYER. EXPECT THE LAKE EFFECT SNOW TO
MAKE IT INTO THE SOUTHERN HALF OF THE BUFFALO METRO AREA FOR A TIME
FRIDAY MORNING...ALSO EXTENDING INTO PORTIONS OF SOUTHERN GENESEE
AND WYOMING COUNTIES. THIS BAND OF SNOW MAY PRODUCE AT LEAST
MODERATE ACCUMULATIONS...WITH UNCERTAINTIES STILL ON THE IMPACT OF
SOMEWHAT DRIER AIR ALOFT AND INCREASING SHEAR WITH THE APPROACH OF
THE ARCTIC FRONT. THIS MAY EVENTUALLY REQUIRE ADDITIONAL LAKE EFFECT
HEADLINES AS THE DETAILS BECOME MORE CERTAIN.
OFF LAKE ONTARIO...
SIMILAR TO LAKE ERIE...LAKE INDUCED INSTABILITY REMAINS STRONG
THROUGH THE PERIOD WITH EQUILIBRIUM LEVELS AROUND 10K FEET. ON
THURSDAY BOUNDARY LAYER FLOW WILL REMAIN NORTHWEST...WITH SNOW ALONG
MUCH OF THE SOUTH SHORE OF THE LAKE. THE 290 WIND DIRECTION SUGGESTS
THERE WILL BE A RELATIVE MAX IN COVERAGE AND INTENSITY ACROSS
WAYNE/NORTHERN CAYUGA/SOUTHERN OSWEGO COUNTIES WHERE THE FETCH IS
MAXIMIZED. MESOSCALE MODEL GUIDANCE CONTINUES TO SUGGEST THE
UPSTREAM CONNECTION TO GEORGIAN BAY WILL RESIDE TO THE WEST OF
ROCHESTER ON THURSDAY. EXPECT ADDITIONAL SNOW AMOUNTS ON THURSDAY OF
3 TO 6 INCHES IN THE MOST FAVORED AREAS OF NORTHERN/EASTERN WAYNE
COUNTY INTO NORTHERN CAYUGA AND FAR SOUTHERN OSWEGO COUNTIES.
FARTHER WEST EXPECT 1 TO 3 INCHES ALONG THE SHORE FROM ROCHESTER TO
PORTIONS OF ORLEANS AND EASTERN NIAGARA COUNTIES. THE WILDCARD IN
THIS AREA IS THE POTENTIAL FOR THE UPSTREAM GEORGIAN BAY CONNECTION
WHICH MAY LOCALLY ENHANCE TOTALS.
THURSDAY NIGHT MAY VERY WELL BE THE TIME OF MOST INTENSE SNOWFALL
FOR A SMALL AREA SOUTHEAST OF LAKE ONTARIO AS THE BAND CONSOLIDATES
WITH BACKING FLOW OVERNIGHT. THE NORTHWEST FLOW WILL BECOME MORE WNW
AND EVENTUALLY WESTERLY...INCREASING FETCH AND CONVERGENCE ALONG THE
LENGTH OF THE LAKE. THIS WILL ALLOW SNOW TO END FROM ROCHESTER
WESTWARD DURING THE EVENING AS THE BAND LIFTS NORTH AND OFFSHORE.
FARTHER EAST...EXPECT AN INTENSIFYING SINGLE BAND OF SNOW OVER
EASTERN WAYNE AND NORTHERN CAYUGA COUNTIES FROM LATE EVENING THROUGH
THE EARLY OVERNIGHT HOURS. TOWARD DAYBREAK FRIDAY BOUNDARY LAYER
FLOW QUICKLY BACKS FURTHER TO WEST AND WSW...WHICH WILL CARRY THE
BAND RAPIDLY NORTHEAST ACROSS OSWEGO COUNTY. ADDITIONAL AMOUNTS
THURSDAY NIGHT SHOULD PEAK FROM SODUS INTO NORTHERN CAYUGA COUNTY
WITH ANOTHER 8-10 INCHES POSSIBLE. EXPECT A QUICK 2-4 INCHES ACROSS
OSWEGO COUNTY LATE THURSDAY NIGHT AS THE BAND MOVES RAPIDLY ACROSS
THE COUNTY.
ON FRIDAY BOUNDARY LAYER FLOW BECOMES ALIGNED FROM THE SOUTHWEST...
WHICH WILL ALLOW THE LAKE EFFECT SNOW TO BECOME BETTER ORGANIZED
AGAIN ACROSS JEFFERSON AND NORTHERN LEWIS COUNTIES. LAKE INDUCED
EQUILIBRIUM LEVELS REMAIN HIGH...ALTHOUGH SHEAR MAY INCREASE WITH
THE APPROACH OF THE ARCTIC FRONT. THIS BAND MAY PRODUCE MODERATE
ACCUMULATIONS NORTHEAST OF LAKE ONTARIO FRIDAY. THIS MAY EVENTUALLY
REQUIRE ADDITIONAL LAKE EFFECT HEADLINES ONCE THE DETAILS BECOME
MORE CERTAIN.
LAST BUT NOT LEAST...A POWERFUL ARCTIC FRONT WILL SURGE SOUTH ACROSS
THE REGION FRIDAY EVENING. THIS ARCTIC FRONT WILL LIKELY CAPTURE AND
MERGE WITH THE LAKE EFFECT SNOW BAND OFF LAKE ONTARIO...WITH A VERY
HEAVY SNOW SQUALL PASSING SOUTH ACROSS MUCH OF THE REGION. THIS WILL
LIKELY PRODUCE AN INCH OR TWO OF SNOW IN MANY AREAS...WITH LOCALLY
HIGHER AMOUNTS SOUTHEAST OF THE LAKES WHERE THE LAKE CONTRIBUTION
MAXIMIZES. BEHIND THE ARCTIC FRONT...MULTIPLE STREAMERS OF LAKE
EFFECT SNOW SHOWERS WILL DEVELOP SOUTH OF THE LAKES LATE FRIDAY
NIGHT AS FLOW BECOMES NORTHWEST AND EVENTUALLY NNW.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
A FRIGID ARCTIC AIRMASS WILL TAKE HOLD OF THE EASTERN GREAT LAKES
AND NEW ENGLAND SATURDAY AS 850MB TEMPS PLUMMET TO AN AVERAGE OF
-32C. TO PUT THIS IN PROSPECTIVE...THE COLDEST TEMPERATURE EVER
RECORDED AT 850MB ON A KBUF SOUNDING IN THE MONTH OF FEBRUARY IS
-28C...AND THE COLDEST EVER RECORDED FOR ANY MONTH IS -32C.
TEMPERATURES WILL DROP INTO THE SINGLE DIGITS ABOVE AND BELOW ZERO BY
EARLY SATURDAY MORNING DEPENDING ON LOCATION. ANY ABOVE ZERO
TEMPERATURES FIRST THING IN THE MORNING WILL LIKELY BE REPLACED BY
SINGLE DIGITS BELOW ZERO EVERYWHERE BY MIDDAY AND AFTERNOON AS THE
CORE OF THE COLDEST AIR ALOFT CROSSES THE AREA. LOWS WILL BE WELL
BELOW ZERO SATURDAY NIGHT...WITH -20 OR BETTER ACROSS THE NORTH
COUNTRY WITH NO MODERATING LAKE INFLUENCE. THE COMBINATION OF
MODERATE WINDS AND FRIGID TEMPERATURES WILL PRODUCE DANGEROUSLY COLD
WIND CHILLS LATE FRIDAY NIGHT THROUGH EARLY SUNDAY MORNING.
THE FRIGID NORTH FLOW OVER THE LAKES WILL PRODUCE WIDESPREAD LAKE
EFFECT SNOW SHOWERS ACROSS WESTERN AND CENTRAL NY. DESPITE THE
EXTREME INSTABILITY...AIRMASSES THIS COLD ARE ALSO VERY DRY AND
TEMPERATURES BECOME TOO COLD FOR DENDRITES. THIS WILL FORCE
SNOWFLAKES TO BE VERY SMALL AND LIMIT ACCUMULATIONS...ALTHOUGH
SEVERAL INCHES ARE LIKELY SOUTH OF BOTH LAKES. THE LAKE EFFECT SNOW
WILL DIMINISH IN COVERAGE AND INTENSITY SUNDAY...BUT NOT END
ALTOGETHER UNTIL SUNDAY NIGHT AS THE HIGH CRESTS OVERHEAD.
THE FRIGID TEMPERATURES WILL BE SHORT LIVED AS STRONG WARM ADVECTION
BRINGS TEMPS BACK TO AVERAGE BY MONDAY AND TUESDAY. THE NEXT
SYNOPTIC SYSTEM WILL MOVE THE REGION BY MONDAY OR TUESDAY WITH A
CHANCE OF SNOW...ALTHOUGH THE GFS AND ECMWF DIFFER A GOOD DEAL ON
THE TIMING AND TRACK DETAILS.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
SLOW-MOVING LOW PRESSURE OVER EASTERN LAKE ONTARIO WILL MOVE EAST
OF THE AREA TODAY. BEHIND THIS SYSTEM...INCREASING MOISTURE AND
DEEPENING COLD AIR CONTINUES WIDESPREAD SNOW AND IFR/LOW MVFR
CONDITIONS TODAY...WHILE WESTERLY FLOW AND ADDED LAKE ENHANCEMENT
REDUCES CONDITIONS TO AS LOW AS LIFR IN MORE LOCALIZED LAKE SNOWS
EAST OF BOTH LAKES.
TONIGHT...EXPECT CONTINUED IFR/LIFR IN AREAS OF HEAVIER LAKE
EFFECT SNOW EAST-SOUTHEAST OF THE LAKES...WITH MVFR/IFR IN
SCATTERED TO NUMEROUS LAKE EFFECT SNOW SHOWERS GENERALLY
PREVAILING ELSEWHERE.
OUTLOOK...
THURSDAY...MVFR/IFR IN SCATTERED TO NUMEROUS LAKE EFFECT SNOW
SHOWERS...AND IFR/LIFR IN AREAS OF HEAVIER LAKE EFFECT SNOW EAST-
SOUTHEAST OF THE LAKES.
FRIDAY...IFR/MVFR WITH SNOW SHOWERS LIKELY...AND AREAS OF HEAVIER
LAKE EFFECT SNOW EAST OF THE LAKES.
SATURDAY...IFR/MVFR IN LAKE EFFECT SNOW SHOWERS SOUTH OF THE LAKES...
WITH MVFR/VFR ACROSS THE NORTH COUNTRY.
SUNDAY...IFR/MVFR IN SCATTERED TO NUMEROUS LAKE EFFECT SNOW SHOWERS
SOUTH OF THE LAKES...WITH MVFR/VFR ACROSS THE NORTH COUNTRY.
&&
.MARINE...
LOW PRESSURE OVER EASTERN LAKE ONTARIO WILL SLIDE EASTWARD INTO NEW
ENGLAND TODAY. IN THE WAKE OF THIS SYSTEM...A BRISK FLOW OF
PROGRESSIVELY COLDER ARCTIC AIR WILL OVERSPREAD THE REGION THROUGH
THE WEEKEND...RESULTING IN A PROLONGED PERIOD OF ADVISORY-WORTHY
WINDS AND WAVES ACROSS THE LOWER LAKES. WITH THIS IN MIND WE HAVE
ELECTED TO EXTEND OUR EXISTING SMALL CRAFT ADVISORIES THROUGH
SATURDAY FOR NOW...THOUGH IT IS QUITE POSSIBLE THAT THESE MAY
EVENTUALLY NEED TO BE EXTENDED EVEN A BIT FURTHER OUT IN TIME.
IN ADDITION TO THE ABOVE...THE PASSAGE OF AN ARCTIC COLD FRONT
FRIDAY EVENING WILL ALSO USHER IN A TRULY FRIGID AIRMASS FOR LATER
FRIDAY NIGHT AND THE UPCOMING WEEKEND...WHICH IN CONJUNCTION WITH
THE EXPECTED BRISK WINDS WILL RESULT IN A GREATLY HEIGHTENED
POTENTIAL FOR HEAVY FREEZING SPRAY.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...LAKE EFFECT SNOW ADVISORY UNTIL 10 PM EST THIS EVENING FOR
NYZ007-008.
LAKE EFFECT SNOW WARNING UNTIL 4 AM EST FRIDAY FOR NYZ004>006.
LAKE EFFECT SNOW WARNING UNTIL 4 PM EST THURSDAY FOR
NYZ001>003-019-020-085.
LAKE EFFECT SNOW ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
NYZ012.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST SATURDAY FOR LEZ040-041.
SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM
EST SATURDAY FOR LOZ043>045.
SMALL CRAFT ADVISORY UNTIL 7 PM EST SATURDAY FOR LOZ042.
&&
$$
SYNOPSIS...JJR
NEAR TERM...JJR/SMITH
SHORT TERM...HITCHCOCK
LONG TERM...HITCHCOCK
AVIATION...JJR/SMITH
MARINE...JJR
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
431 PM EST WED FEB 10 2016
.SYNOPSIS...
ARCTIC HIGH PRESSURE WILL BUILD IN FROM THE NORTHWEST THROUGH
EARLY FRIDAY. WEAK LOW PRESSURE WILL MOVE ACROSS JUST SOUTH OF THE
AREA FRIDAY...FOLLOWED BY ANOTHER BLAST OF ARCTIC AIR FOR THE
WEEKEND. LOW PRESSURE WILL APPROACH FROM THE SOUTHWEST MONDAY AND
MOVE ACROSS THE AREA TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 315 PM WEDNESDAY...SCATTERED CUMULUS SHOULD DISSIPATE WITH
LOSS OF HEATING BY EARLY EVENING LEAVING US WITH A CLEAR COLD AND
BREEZY NIGHT ACROSS EASTERN NC. WINDS WILL LIKELY INCREASE A BIT
AS WEAK SURFACE TROUGH PASSES OFFSHORE BY EARLY EVENING. WENT WITH
A CONSENSUS BLEND OF MINIMUM TEMPERATURE FORECASTS TONIGHT WITH
LOWS IN THE LOW/MID 20S MOST AREAS WITH UPPER 20S OUTER BANKS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
AS OF 315 PM WEDNESDAY...DESPITE SOME SLIGHT MID-LEVEL HEIGHT
RISES ON THURSDAY...THE FORECAST 2-METER TEMPERATURES ARE ACTUALLY
A COUPLE OF DEGREES COOLER. UNDER GENERALLY SUNNY SKIES...EXCEPT
FOR SOME DAYTIME CUMULUS...HIGH TEMPERATURES AGAIN STRUGGLE TO
REACH 40 DEGREES OVER MUCH OF THE CWA...WITH MANY SPOTS REMAINING
IN THE UPPER 30S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
BELOW NORMAL TEMPERATURES THROUGH EARLY NEXT WEEK...WITH ARCTIC
AIRMASS MOVING INTO EASTERN NC THIS WEEKEND. THERE IS THE POTENTIAL
FOR A WINTRY WEATHER WITH ACCUMULATING SNOW FOR FRIDAY.
THURSDAY NIGHT THROUGH FRIDAY NIGHT...
SHORTWAVE ENERGY WILL DROP DOWN FROM CANADA...ACCOMPANIED BY ~125KT
JETSTREAK FRIDAY...LEADING TO RE-AMPLIFYING THE UPPER LEVEL TROUGH
OVER THE EASTERN HALF U.S. AND BRINGING EVEN COLDER ARCTIC AIRMASS
INTO THE SOUTHEAST REGION OVER THE WEEKEND.
SFC HIGH WILL BE OVER THE AREA WHILE A SFC LOW DEVELOP/STRENGTHENS
OFF THE SOUTHEAST/CAROLINA COAST. CURRENT CHALLENGE ARE THE LATEST
MODELS NOT BEING CONSISTENT. 10/12Z NAM FORECASTING SOUNDING
SOUNDINGS INDICATES SATURATION IN THE SNOW GROWTH ZONE REGION WITH A
SLIGHT WARM NOSE...ESPECIALLY ALONG OUR SOUTHERN-MOST
COUNTIES...WITH POSSIBLE WINTRY MIX; SLEET AND POSSIBLE
-FZRA FOR THE SOUTHERN ZONES AND -SN FOR THE NORTHERN COUNTIES.
MEANWHILE...10/12Z GFS FORECASTING SOUNDING HAS A STRONGER WARM NOSE
AND LESS SATURATED IN THE SNOW GROWTH ZONE REGION THAN THE 12Z NAM.
BOTH 10/12Z GFS AND 10/12Z ECMWF HAVE SOME CONSISTENCY WITH SNOW
DEVELOPING ALONG TO THE COUNTIES ALONG SOUNDS...MAINLY NORTHERN
PAMLICO AND ALBEMARLE SOUND. PLUS, WITH THE LATEST GUIDANCE FROM WPC
PROBABLISTIC WINTER GUIDANCE...CONFIDENCE HAVE INCREASED AND MADE
ADJUSTMENTS FOR FRIDAY FORECAST. EXPECT LIGHT SNOW WEST OF HWY 17
WITH A WINTRY MIX TO THE SOUTH...THEN SNOW WILL MOVE NORTH OF HWY 70
IN THE AFTERNOON...MEANWHILE THE SOUTHERN COUNTIES WILL BE MAINLY A
MIX OF -RA/-SN.
SATURDAY THROUGH SUNDAY: A SECONDARY COLD FRONT WILL PUSH THROUGH
THE AREA FRIDAY NIGHT INTO EARLY SATURDAY...BRINGING EVEN
COLDER/DRIER AIRMASS INTO THE REGION.VERY STRONG HIGH PRESSURE WILL
BUILD INTO THE REGION FROM THE NORTHWEST. THE 850MB TEMPS WILL
PLUMMET BY SUNDAY BTW -15C TO -20C WITH LOW LEVEL THICKNESS DROPPING
INTO THE 1225-1240M RANGE. THIS WILL BRING VERY COLD TEMPERATURES
ACROSS THE AREA...WITH HIGH STRUGGLING TO REACH FREEZING ON SUNDAY.
SATURDAY`S HIGHS...MID 30S/UPPER 30S AND SUNDAY`S HIGHS IN THE UPPER
20S/LOW 30S. OVERNIGHT LOWS...MID/UPPER TEENS TO LOW 20S FOR BOTH
SATURDAY SUNDAY NIGHT.
MONDAY THROUGH WEDNESDAY...THE LONG WAVE TROUGH AXIS AND SFC HIGH
PRESSURE WILL SHIFT OFFSHORE ON MONDAY AS THE NEXT SHORTWAVE COMES
IN FROM THE CENTRAL PLAINS AND DEVELOPING A SFC LOW DEVELOP OFF THE
CAROLINA COAST. INCREASED POPS FOR MONDAY AND TUESDAY AS THE BEST
CHANCES WITH PRECIP. PRECIP COULD BEGIN AS -RA/-SN MIX MONDAY
MORNING BEFORE TRANSITIONING TO ALL RAIN. THE SFC LOW WILL LIFT TO
THE NORTHEAST AS THE TROUGH AXIS SWINGS ACROSS EASTERN NC TUESDAY
NIGHT. SFC HIGH PRESSURE WILL BUILD IN FROM SOUTHWEST. TEMPERATURES
WILL BEGIN TO REBOUND MONDAY AS HIGHS ARE EXPECTED TO REACH INTO THE
40S MONDAY... IN THE LOW 50S TUESDAY AND BY WEDNESDAY MID 50S.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
SHORT TERM /THROUGH 18Z THURSDAY/...
AS OF 1250 PM WEDNESDAY...HIGH CONFIDENCE FOR VFR CONDITIONS
CONTINUE THROUGH THIS TAF CYCLE. OTHER THAN A FEW SCATTERED
CUMULUS AROUND 5000 FEET OR SO...SKIES WILL BE CLEAR THIS
AFTERNOON AND INTO TONIGHT. THERE SHOULD BE SUFFICIENT MIXING TO
PRECLUDE FOG DEVELOPMENT AGAIN TONIGHT. ONLY SCATTERED CLOUDS ARE
EXPECTED AGAIN ON THURSDAY.
LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 330 PM WED...MAINLY VFR CONDITIONS FOR MOST OF THE FORECAST
PERIOD...EXCEPT FOR FRIDAY AND MONDAY. MVFR CONDITIONS WILL BE
LIKELY FRIDAY AS A SFC LOW DEVELOPS/STRENGTHS ALONG THE CAROLINA
COAST...BRINGING THE THREAT OF MIX WINTRY PRECIPITATION ACROSS THE
AREA. VFR CONDITIONS RETURNS LATE FRIDAY NIGHT AS A COLD FRONT WILL
PUSH THROUGH WITH HIGH PRESSURE BUILDING BEHIND IT AND WILL CONTINUE
THROUGH SUNDAY. POSSIBLE MVFR CONDITIONS FOR MONDAY WITH THE
DEVELOPMENT OF A SFC LOW TO THE SOUTHEAST COAST.
&&
.MARINE...
SHORT TERM /TONIGHT AND THURSDAY/...
AS OF 315 PM WEDNESDAY...THE HIGH-RESOLUTION HRRR AND RAP MODELS
HAVE DEPICTED THE FLUCTUATION IN WIND SPEED QUITE WELL TODAY WITH
A BIT OF AN AFTERNOON LULL. THIS WILL BE FOLLOWED BY AN INCREASE
IN WINDS THIS EVENING AS A SURFACE TROUGH ACROSS THE PIEDMONT
MOVES OFFSHORE AND GUSTY WEST WINDS 15-25 KNOTS WITH PERHAPS SOME
GUSTS INTO THE 30S ARE POSSIBLE. SEAS HAVE SUBSIDED BUT WILL
REMAIN IN THE 4-7 FOOT RANGE TONIGHT INTO THURSDAY AS THE WINDS
INCREASE. NO CHANGES TO CURRENT ADVISORIES AT THIS TIME THROUGH
THE SHORT TERM PERIOD.
LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 330 PM WED...POOR BOATING CONDITIONS WILL BE EXPECTED FOR MOST
OF THE FORECAST PERIOD...EXCEPT FOR FRIDAY. HIGH PRESSURE WILL BE
BUILT TO THE NORTH...MEANWHILE A LOW PRESSURE SYSTEM WILL
DEVELOP/STRENGTH OVER THE SOUTHEAST/CAROLINA COAST ON FRIDAY. WINDS
WILL SHIFT FROM THE NW TO NE 10-15 KNOTS AND SEAS 2 TO 3 FT FRIDAY.
WINDS AND SEA WILL INCREASE AGAIN EARLY SATURDAY ON THE BACKSIDE OF
THE SFC LOW AND AHEAD OF THE COLD FRONT. SMALL CRAFT ADVISORY
CONDITIONS WILL RE-DEVELOP LATE FRIDAY NIGHT/EARLY SATURDAY INTO
SUNDAY OVER THE COASTAL WATERS/PAMLICO SOUND. NW WINDS 20-30 KNOTS
WITH SEAS BUILDING 5-8FT. WINDS ARE EXPECTED TO PEAK SATURDAY NIGHT
INTO EARLY SUNDAY...WITH POSSIBLE GALE FORCE WIND GUSTS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THURSDAY FOR AMZ135-150-
156-158.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST THURSDAY NIGHT FOR
AMZ152-154.
&&
$$
SYNOPSIS...CTC
NEAR TERM...CTC
SHORT TERM...CTC
LONG TERM...BM
AVIATION...CTC/BM
MARINE...CTC/BM
TIDES/COASTAL FLOODING...MHX
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1255 PM EST WED FEB 10 2016
.SYNOPSIS...
ARCTIC HIGH PRESSURE WILL BUILD IN FROM THE NORTHWEST THROUGH
EARLY FRIDAY. WEAK LOW PRESSURE WILL MOVE ACROSS JUST SOUTH OF THE
AREA FRIDAY...FOLLOWED BY ANOTHER BLAST OF ARCTIC AIR FOR THE
WEEKEND. LOW PRESSURE WILL APPROACH FROM THE SOUTHWEST MONDAY AND
MOVE ACROSS THE AREA TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1250 PM WEDNESDAY...SKIES REMAIN SUNNY ACROSS THE REGION
WITH A FEW SCATTERED CUMULUS SHOWING UP ON SATELLITE JUST
SOUTHWEST OF THE CWA. TEMPERATURES WILL BE SLOW TO RISE MUCH THIS
AFTERNOON AS HIGH WILL TOP OUT IN THE LOWER 40S. NO MAJOR CHANGES
TO THE CURRENT FORECAST AT THIS TIME.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
AS OF 300 AM WEDNESDAY...BASE OF UPR TROF EXPECTED TO MOVE ACROSS
AREA THIS EVENING...LEADING TO CLEARING SKIES OVERNIGHT. LOW LVLS
WILL REMAIN MIXED WITH PERSISTENT WEST WINDS 5-15 MPH WHICH WILL
INHIBIT MAX RADIATIONAL COOLING...BUT COLD AND DRY AIR MASS WILL
STILL RESULT IN MIN TEMPS LOW TO MID 20S INLAND AND AROUND 30 OBX.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 510 AM WED...BELOW NORMAL TEMPERATURES THROUGH EARLY NEXT
WEEK...AS ARCTIC AIRMASS INVADES EASTERN NC THIS WEEKEND. THERE IS
THE POTENTIAL FOR WINTRY WX WITH ACCUMULATING SNOW FRIDAY.
HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE NW THU INTO FRI AS
UPPER LEVEL ENERGY CONTINUES TO ROTATE ALONG THE BASE OF THE EAST
COAST UPPER TROUGH. LOW LEVEL THICKNESS VALUES AND SUNNY SKIES
SUPPORT HIGHS IN THE UPPER 30S TO LOW 40S THU...WITH LOWS DROPPING
INTO THE 20S THU NIGHT.
HIGH PRESSURE IN PLACE FRIDAY...AS AN AREA OF LOW PRESSURE OVER
THE SE STATES STRENGTHENS MOVING ALONG THE NC COAST. STILL SOME
UNCERTAINTY ON TRACK AND STRENGTH OF THE LOW BUT GIVEN THE TRENDS
MADE SOME FAIRLY SIGNIFICANT CHANGES TO PREVIOUS FORECAST. 00Z
MODEL GUIDANCE NOW TRENDING MUCH WETTER FOR FRI. THERMAL
PROFILES...CRITICAL THICKNESS VALUES AND SREF PLUMES SUPPORT
PREDOMINANT PTYPE AS -SN WITH MAYBE A MIX OF -SN/-RA ALONG THE
COAST...WITH FORECAST SOUNDINGS SHOWING GOOD SATURATION IN THE
DENDRITIC SNOW GROWTH ZONE REGION. FORECAST SOUNDINGS ALSO DEVELOP
A SLIGHT WARM NOSE ALOFT...SO SOME SLEET AND POSSIBLY -FZRA COULD
ALSO BE MIXED IN WITH THE PRECIP...ESP ACROSS THE SOUTHERN ZONES.
INCREASED POPS TO HIGH CHANCE ACROSS THE AREA FRI WITH HIGHER POPS
E OF HWY 17...AND ADDED LIGHT SNOW ACCUMULATIONS. LIGHT SNOW
ACCUMULATIONS ARE LIKELY ACROSS THE AREA...LATE FRIDAY MORNING/EARLY
AFTERNOON THROUGH FRIDAY EVENING. HOWEVER, A SLIGHT SHIFT IN TRACK
OF THE LOW COULD IMPACT THE FORECAST GREATLY AND THE POTENTIAL
IMPACTS.
A STRONG ARCTIC COLD FRONT WILL PUSH THROUGH THE AREA FRIDAY
NIGHT INTO EARLY SATURDAY...BRINGING A MUCH COLDER/DRIER AIRMASS TO
THE REGION. VERY STRONG HIGH PRESSURE WILL BUILD IN FROM THE
NORTHWEST THROUGH THE WEEKEND. 850MB TEMPS WILL PLUMMET TO -15 TO
-20C BY SUNDAY WITH LOW LEVEL THICKNESS DROPPING INTO THE
1225-1240M RANGE...RESULTING IN VERY COLD TEMPERATURES THIS
WEEKEND. SOME RECORD LOW MAX VALUES WILL BE POSSIBLE. LOW LEVEL
THICKNESS VALUES SUPPORT HIGHS 35-40 DEGREES SAT...AND THEN UPPER
20S TO LOW 30S SUNDAY. OVERNIGHT LOWS...MID/UPPER TEENS TO LOW 20S
FOR BOTH SATURDAY AND SUNDAY NIGHTS. THE OUTER BANKS COULD SEE
SOME FLURRIES OR VERY LIGHT SNOW SHOWERS ON AND OFF SAT INTO SUN.
WIND CHILL VALUES IN THE SINGLE DIGITS LIKELY SAT NIGHT INTO
SUNDAY MORNING ACROSS THE REGION.
HIGH PRESSURE WILL SHIFT OFF THE COAST MONDAY AS NEXT SYSTEM
APPROACHES THE AREA. STRONG SHORTWAVE MOVING OUT OF THE CENTRAL
PLAINS WILL MOVE EASTWARD...INDUCING CYCLOGENESIS OFF THE SE
COAST MONDAY NIGHT AND TUE. SLIGHT MODEL DIFFERENCES CONTINUE
REGARDING THE TIMING...STRENGTH OF THE SHORTWAVE AND THEN SFC
LOW. WILL CONTINUE SC/LOW CHANCE POPS AT THIS TIME...WITH BEST
CHANCES MONDAY NIGHT AND TUESDAY. PRECIP COULD BEGIN AS -RA/-SN
MIX MONDAY MORNING BEFORE TRANSITIONING TO ALL RAIN. TEMPS LOOK
TO REBOUND AND RETURN TO NEAR CLIMO...HIGHS MON 40-50 DEGREES AND
TUE IN THE LOW/MID 50S.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
SHORT TERM /THROUGH 18Z THURSDAY/...
AS OF 1250 PM WEDNESDAY...HIGH CONFIDENCE FOR VFR CONDITIONS
CONTINUE THROUGH THIS TAF CYCLE. OTHER THAN A FEW SCATTERED
CUMULUS AROUND 5000 FEET OR SO...SKIES WILL BE CLEAR THIS
AFTERNOON AND INTO TONIGHT. THERE SHOULD BE SUFFICIENT MIXING TO
PRECLUDE FOG DEVELOPMENT AGAIN TONIGHT. ONLY SCATTERED CLOUDS ARE
EXPECTED AGAIN ON THURSDAY.
LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 3 AM WED...PRED VFR
CONDITIONS EXPECTED THU AND THU NIGHT. WESTERLY WIND GUSTS TO 25KT
THU AFTERNOON. SUB-VFR CONDITIONS WILL BE LIKELY FRIDAY AS AN AREA
OF LOW PRESSURE MOVES ALONG THE NC COAST...BRINGING THE THREAT OF
WINTRY PRECIPITATION TO THE TERMINALS. A PERIOD OF LIGHT
SNOW...MAYBE MIXED WITH LIGHT RAIN AND SLEET WILL BE POSSIBLE LATE
FRIDAY MORNING/EARLY AFTERNOON INTO THE EARLY EVENING. PRED VFR
CONDITIONS EXPECTED TO RETURN LATE FRIDAY NIGHT AND CONTINUE
THROUGH SUNDAY.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 1250 PM WEDNESDAY...WINDS HAVE DIMINISHED A BIT AS FORECAST
BY THE 3KM HRRR AND RAP MODELS. AS A WEAK SURFACE TROUGH PASSES
OFFSHORE DURING THE LATE AFTERNOON...THE HIGH-RESOLUTION MODELS
CONTINUE TO SHOW WINDS INCREASING AND BECOMING GUSTY BY THIS
EVENING FROM THE WEST AT 15-25 KNOTS. SEAS HAVE SUBSIDED QUITE A
BIT THIS MORNING AND ARE CURRENTLY IN THE 4-7 FOOT RANGE AND
SHOULD LEVEL OFF AT 4 TO 6 FEET FOR TONIGHT.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 3 AM WED...UNSETTLED BOATING CONDITIONS EXPECTED FOR MOST OF
THE PERIOD. HIGH PRESSURE WILL BUILD IN FROM THE NW THU AND FRI.
GUSTY WNW WINDS 15-25KT AND ELEVATED SEAS WILL START OFF THU...BUT
SHOULD BE GRADUALLY SUBSIDING THROUGH THE DAY. COULD SEE SEAS DROP
BELOW 6FT BY THU EVENING. AN AREA OF LOW PRESSURE WILL MOVE ALONG
THE NC COAST FRIDAY...WHILE STILL SOME UNCERTAINTY REGARDING THE
TRACK AND STRENGTH OF THE LOW, INCREASED WINDS SLIGHTLY FOR
FRI. THOUGH WILL KEEP AOB 15KT WITH SEAS 2-4FT. EXPECT STRONGER
WINDS LATE FRI AND FRI NIGHT ON THE BACKSIDE OF THE LOW AND AHEAD
OF THE APPROACHING FRONT. A STRONG ARCTIC FRONT WILL MOVE THROUGH
THE WATERS FRIDAY NIGHT INTO EARLY SATURDAY. SCA CONDITIONS
EXPECTED TO RE-DEVELOP FRIDAY NIGHT AND CONTINUE THROUGH SUNDAY.
NW WINDS WILL INCREASE TO 20-30KT WITH SEAS BUILDING TO 5-9FT.
WINDS WILL PEAK SAT NIGHT AND EARLY SUNDAY MORNING...WITH GALE
FORCE WIND GUSTS POSSIBLE.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THURSDAY FOR AMZ135-150-
156-158.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST THURSDAY NIGHT FOR
AMZ152-154.
&&
$$
SYNOPSIS...JBM
NEAR TERM...CTC
SHORT TERM...JBM
LONG TERM...CQD
AVIATION...CTC/CQD
MARINE...CTC/CQD
TIDES/COASTAL FLOODING...MHX
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
953 AM EST WED FEB 10 2016
.SYNOPSIS...
ARCTIC HIGH PRESSURE WILL BUILD IN FROM THE NORTHWEST THROUGH
EARLY FRIDAY. WEAK LOW PRESSURE WILL MOVE ACROSS JUST SOUTH OF THE
AREA FRIDAY...FOLLOWED BY ANOTHER BLAST OF ARCTIC AIR FOR THE
WEEKEND. LOW PRESSURE WILL APPROACH FROM THE SOUTHWEST MONDAY AND
MOVE ACROSS THE AREA TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 955 AM WEDNESDAY...ONLY A FEW CHANGES WITH THIS UPDATE.
SKIES ARE GENERALLY CLEAR ACROSS THE REGION AND HAVE IMPROVED SKY
COVER. FORECAST SOUNDINGS DO SHOW SOME INCREASED MOISTURE AROUND
5000 FEET LATER IN THE AFTERNOON...BUT THINK MOST OF THE DAY WILL
BE SUNNY. TEMPERATURES WILL STRUGGLE TO GET INTO THE LOWER 40S AND
NO CHANGES TO TEMP FORECAST AT THIS TIME.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
AS OF 300 AM WEDNESDAY...BASE OF UPR TROF EXPECTED TO MOVE ACROSS
AREA THIS EVENING...LEADING TO CLEARING SKIES OVERNIGHT. LOW LVLS
WILL REMAIN MIXED WITH PERSISTENT WEST WINDS 5-15 MPH WHICH WILL
INHIBIT MAX RADIATIONAL COOLING...BUT COLD AND DRY AIR MASS WILL
STILL RESULT IN MIN TEMPS LOW TO MID 20S INLAND AND AROUND 30 OBX.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 510 AM WED...BELOW NORMAL TEMPERATURES THROUGH EARLY NEXT
WEEK...AS ARCTIC AIRMASS INVADES EASTERN NC THIS WEEKEND. THERE IS
THE POTENTIAL FOR WINTRY WX WITH ACCUMULATING SNOW FRIDAY.
HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE NW THU INTO FRI AS
UPPER LEVEL ENERGY CONTINUES TO ROTATE ALONG THE BASE OF THE EAST
COAST UPPER TROUGH. LOW LEVEL THICKNESS VALUES AND SUNNY SKIES
SUPPORT HIGHS IN THE UPPER 30S TO LOW 40S THU...WITH LOWS DROPPING
INTO THE 20S THU NIGHT.
HIGH PRESSURE IN PLACE FRIDAY...AS AN AREA OF LOW PRESSURE OVER
THE SE STATES STRENGTHENS MOVING ALONG THE NC COAST. STILL SOME
UNCERTAINTY ON TRACK AND STRENGTH OF THE LOW BUT GIVEN THE TRENDS
MADE SOME FAIRLY SIGNIFICANT CHANGES TO PREVIOUS FORECAST. 00Z
MODEL GUIDANCE NOW TRENDING MUCH WETTER FOR FRI. THERMAL
PROFILES...CRITICAL THICKNESS VALUES AND SREF PLUMES SUPPORT
PREDOMINANT PTYPE AS -SN WITH MAYBE A MIX OF -SN/-RA ALONG THE
COAST...WITH FORECAST SOUNDINGS SHOWING GOOD SATURATION IN THE
DENDRITIC SNOW GROWTH ZONE REGION. FORECAST SOUNDINGS ALSO DEVELOP
A SLIGHT WARM NOSE ALOFT...SO SOME SLEET AND POSSIBLY -FZRA COULD
ALSO BE MIXED IN WITH THE PRECIP...ESP ACROSS THE SOUTHERN ZONES.
INCREASED POPS TO HIGH CHANCE ACROSS THE AREA FRI WITH HIGHER POPS
E OF HWY 17...AND ADDED LIGHT SNOW ACCUMULATIONS. LIGHT SNOW
ACCUMULATIONS ARE LIKELY ACROSS THE AREA...LATE FRIDAY MORNING/EARLY
AFTERNOON THROUGH FRIDAY EVENING. HOWEVER, A SLIGHT SHIFT IN TRACK
OF THE LOW COULD IMPACT THE FORECAST GREATLY AND THE POTENTIAL
IMPACTS.
A STRONG ARCTIC COLD FRONT WILL PUSH THROUGH THE AREA FRIDAY
NIGHT INTO EARLY SATURDAY...BRINGING A MUCH COLDER/DRIER AIRMASS TO
THE REGION. VERY STRONG HIGH PRESSURE WILL BUILD IN FROM THE
NORTHWEST THROUGH THE WEEKEND. 850MB TEMPS WILL PLUMMET TO -15 TO
-20C BY SUNDAY WITH LOW LEVEL THICKNESS DROPPING INTO THE
1225-1240M RANGE...RESULTING IN VERY COLD TEMPERATURES THIS
WEEKEND. SOME RECORD LOW MAX VALUES WILL BE POSSIBLE. LOW LEVEL
THICKNESS VALUES SUPPORT HIGHS 35-40 DEGREES SAT...AND THEN UPPER
20S TO LOW 30S SUNDAY. OVERNIGHT LOWS...MID/UPPER TEENS TO LOW 20S
FOR BOTH SATURDAY AND SUNDAY NIGHTS. THE OUTER BANKS COULD SEE
SOME FLURRIES OR VERY LIGHT SNOW SHOWERS ON AND OFF SAT INTO SUN.
WIND CHILL VALUES IN THE SINGLE DIGITS LIKELY SAT NIGHT INTO
SUNDAY MORNING ACROSS THE REGION.
HIGH PRESSURE WILL SHIFT OFF THE COAST MONDAY AS NEXT SYSTEM
APPROACHES THE AREA. STRONG SHORTWAVE MOVING OUT OF THE CENTRAL
PLAINS WILL MOVE EASTWARD...INDUCING CYCLOGENESIS OFF THE SE
COAST MONDAY NIGHT AND TUE. SLIGHT MODEL DIFFERENCES CONTINUE
REGARDING THE TIMING...STRENGTH OF THE SHORTWAVE AND THEN SFC
LOW. WILL CONTINUE SC/LOW CHANCE POPS AT THIS TIME...WITH BEST
CHANCES MONDAY NIGHT AND TUESDAY. PRECIP COULD BEGIN AS -RA/-SN
MIX MONDAY MORNING BEFORE TRANSITIONING TO ALL RAIN. TEMPS LOOK
TO REBOUND AND RETURN TO NEAR CLIMO...HIGHS MON 40-50 DEGREES AND
TUE IN THE LOW/MID 50S.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM /THROUGH 12Z THURSDAY/...
AS OF 630 AM WEDNESDAY...HIGH CONFIDENCE OF VFR CONDITIONS
THROUGH TAF PERIOD. CURRENT SKC CONDITIONS WILL PREVAIL NEXT
SEVERAL HOURS...THEN ADDITIONAL SHRT WV ENERGY WILL RESULT IN
SCT-BKN SCU AND AC DEVELOPMENT LATE MORNING THROUGH AFTN WITH ANY
CIGS ABV 3K FT. CLOUDS DISSIPATING WITH LOSS OF HEATING THIS
EVENING. WEST WINDS WILL GUST TO 20 KT AGAIN LATE MORNING THROUGH
AFTN. DRY AND MIXED ATMOS WILL PERSIST OVERNIGHT...INHIBITING FOG
DEVELOPMENT.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 3 AM WED...PRED VFR CONDITIONS EXPECTED THU AND THU NIGHT.
WESTERLY WIND GUSTS TO 25KT THU AFTERNOON. SUB-VFR CONDITIONS WILL
BE LIKELY FRIDAY AS AN AREA OF LOW PRESSURE MOVES ALONG THE NC
COAST...BRINGING THE THREAT OF WINTRY PRECIPITATION TO THE
TERMINALS. A PERIOD OF LIGHT SNOW...MAYBE MIXED WITH LIGHT RAIN
AND SLEET WILL BE POSSIBLE LATE FRIDAY MORNING/EARLY AFTERNOON
INTO THE EARLY EVENING. PRED VFR CONDITIONS EXPECTED TO RETURN
LATE FRIDAY NIGHT AND CONTINUE THROUGH SUNDAY.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 955 AM WEDNESDAY...LATEST 3KM HRRR AND RAP MODELS SHOW GUSTY
WESTERLY WINDS DIMINISHING A BIT THROUGH THE AFTERNOON THEN
INCREASING AGAIN AROUND DARK PER PREVIOUS FORECAST. SEAS HAVE
DROPPED SIGNIFICANTLY SINCE YESTERDAY...BUT REMAIN IN THE 6-9 FOOT
RANGE ALONG THE CENTRAL AND NORTHERN COASTAL WATERS. LIKEWISE THE
E-NE LONG PERIOD SWELL IS SLOWLY BEGINNING TO DIMINISH. AS USUAL
WITH THIS PATTERN...WW3 HAS INITIALIZED BETTER WITH OBSERVED SEAS
AS NWPS IS TOO HIGH WITH OFFSHORE FLOW. ADJUSTED WAVE HEIGHT FCST
WITH WW3 AND WILL INDICATE HEIGHTS SUBSIDING TO 4-6 FT OUTER
PORTIONS OF SRN AND CENTRAL WATERS THIS AFTN...BUT THEN INCREASING
BACK UP TO 5-7 FT TONIGHT.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 3 AM WED...UNSETTLED BOATING CONDITIONS EXPECTED FOR MOST OF
THE PERIOD. HIGH PRESSURE WILL BUILD IN FROM THE NW THU AND FRI.
GUSTY WNW WINDS 15-25KT AND ELEVATED SEAS WILL START OFF THU...BUT
SHOULD BE GRADUALLY SUBSIDING THROUGH THE DAY. COULD SEE SEAS DROP
BELOW 6FT BY THU EVENING. AN AREA OF LOW PRESSURE WILL MOVE ALONG
THE NC COAST FRIDAY...WHILE STILL SOME UNCERTAINTY REGARDING THE
TRACK AND STRENGTH OF THE LOW, INCREASED WINDS SLIGHTLY FOR
FRI. THOUGH WILL KEEP AOB 15KT WITH SEAS 2-4FT. EXPECT STRONGER
WINDS LATE FRI AND FRI NIGHT ON THE BACKSIDE OF THE LOW AND AHEAD
OF THE APPROACHING FRONT. A STRONG ARCTIC FRONT WILL MOVE THROUGH
THE WATERS FRIDAY NIGHT INTO EARLY SATURDAY. SCA CONDITIONS
EXPECTED TO RE-DEVELOP FRIDAY NIGHT AND CONTINUE THROUGH SUNDAY.
NW WINDS WILL INCREASE TO 20-30KT WITH SEAS BUILDING TO 5-9FT.
WINDS WILL PEAK SAT NIGHT AND EARLY SUNDAY MORNING...WITH GALE
FORCE WIND GUSTS POSSIBLE.
&&
.TIDES/COASTAL FLOODING...
AS OF 300 AM WEDNESDAY...LATEST GDNC IS IN LINE WITH PREVIOUS FCST
THINKING OF DIMINISHING E-NE SWELL COMBINING WITH HIGH
ASTRONOMICAL TIDES TO PRODUCE ANOTHER BOUT OF MINOR COASTAL
FLOODING FOR OUTER BANKS AROUND HIGH TIDE THIS MORNING. WILL
CONTINUE COASTAL FLOOD ADVISORY THERE UNTIL NOON TO ACCOUNT FOR
ANY ADDITIONAL OCEAN OVERWASH AND BEACH EROSION THAT MAY OCCUR.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...COASTAL FLOOD ADVISORY UNTIL NOON EST TODAY FOR NCZ103-104.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THURSDAY FOR AMZ135-150-
156-158.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST THURSDAY NIGHT FOR
AMZ152-154.
&&
$$
SYNOPSIS...JBM
NEAR TERM...CTC
SHORT TERM...JBM
LONG TERM...CQD
AVIATION...JBM/CQD
MARINE...CTC/JBM/CQD
TIDES/COASTAL FLOODING...MHX
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
313 AM EST WED FEB 10 2016
.SYNOPSIS...
ARCTIC HIGH PRESSURE WILL BUILD IN FROM THE NORTHWEST TONIGHT
THROUGH EARLY FRIDAY. AN AREA OF LOW PRESSURE WILL MOVE ALONG THE
NORTH CAROLINA COAST FRIDAY. AN ARCTIC COLD FRONT WILL MOVE
THROUGH THE AREA FRIDAY NIGHT FOLLOWED BY THE A BLAST OF VERY COLD
AIR FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1230 AM WEDNESDAY...ADJUSTED SKY COVER FCST FOR MORE
CLEARING OVERNIGHT WITH MINOR CHANGES TO HOURLY TEMP/DEW PT GRIDS.
AC DECK HAS SPREAD ACROSS MOST OF SRN 2/3 OF AREA AND PROGGED TO
MOVE OFF COAST NEXT 2-3 HOURS. MOSTLY CLEAR SKIES EXPECTED ACROSS
AREA REST OF NIGHT AFTER THIS CLOUDINESS PUSHES OFFSHORE. DEW PTS
ARE DROPPING INTO TEENS INLAND BUT WESTERLY WINDS 5-15 MPH WILL
KEEP ATMOS MIXED OVERNIGHT...AND HOLD MIN TEMPS IN UPR 20S INLAND
AND LOW-MID 30S COAST.
/PREVIOUS DISCUSSION/
AS OF 900 PM TUESDAY...YET ANOTHER IN A SERIES OF MID LEVEL
SHORTWAVES SWINGING ACROSS THE REGION IN THE DEEPLY CYCLONIC FLOW
ALOFT CONTINUES TO PRODUCE SCATTERED SHOWERS THIS EVENING. THE
HIGH RESOLUTION GUIDANCE HANGS ON TO THESE SHOWERS UNTIL AROUND
03Z THEN INDICATES DRYING WITH SKIES CLEARING AFTER 06Z. THERE
WILL BE ENOUGH OF A GRADIENT OVERNIGHT TO SUSTAIN WESTERLY WINDS 5
TO 10 MPH INLAND AND 15 TO 25 MPH COAST. THESE WINDS COUPLED WITH
TEMPERATURES PROJECTED TO FALL INTO THE MID AND UPPER 20S INLAND
AND LOW 30S OUTER BANKS WILL ADD AN ADDITIONAL CHILL TO THE AIR.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 AM THURSDAY/...
AS OF 315 PM TUESDAY...FORECAST SOUNDINGS SHOWING SOME LINGERING
MOISTURE BETWEEN 750 AND 850 MB WEDNESDAY AFTERNOON...WHICH SHOULD
YIELD PARTLY CLOUDY SKIES. ANOMALOUSLY LOW THICKNESSES SHOULD LEAD
TO A CHILLY DAY WITH HIGHS GENERALLY IN THE LOWER 40S WITH WEST
WINDS 10 TO 15 MPH WITH A FEW HIGHER GUSTS MAKING IT FEEL EVEN
COLDER.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 3 AM WED...BELOW NORMAL TEMPERATURES THROUGH EARLY NEXT
WEEK...WITH ARCTIC AIRMASS MOVING INTO EASTERN NC THIS WEEKEND.
THERE IS THE POTENTIAL FOR WINTRY WX WITH ACCUMULATING SNOW
FRIDAY.
HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE NW THU INTO FRI AS
UPPER LEVEL ENERGY CONTINUES TO ROTATE ALONG THE BASE OF THE EAST
COAST UPPER TROUGH. LOW LEVEL THICKNESS VALUES AND SUNNY SKIES
SUPPORT HIGHS IN THE UPPER 30S TO LOW 40S THU...WITH LOWS DROPPING
INTO THE 20S THU NIGHT.
HIGH PRESSURE IN PLACE FRIDAY...AS AN AREA OF LOW PRESSURE OVER
THE SE STATES STRENGTHENS MOVING ALONG THE NC COAST. STILL SOME
UNCERTAINTY ON TRACK AND STRENGTH OF THE LOW BUT GIVEN THE TRENDS
MADE SOME FAIRLY SIGNIFICANT CHANGES TO PREVIOUS FORECAST. 00Z
MODEL GUIDANCE NOW TRENDING MUCH WETTER FOR FRI. THERMAL
PROFILES...CRITICAL THICKNESS VALUES AND SREF PLUMES SUPPORT
PREDOMINANT PTYPE AS -SN WITH MAYBE A MIX OF -SN/-RA ALONG THE
COAST. FORECAST SOUNDINGS ALSO SHOW A LITTLE WARM NOSE...SO SOME
SLEET COULD ALSO BE MIXED IN WITH THE PRECIP. INCREASED POPS TO
HIGH CHANCE ACROSS THE AREA FRI...AND ADDED LIGHT SNOW
ACCUMULATIONS. LIGHT SNOW ACCUMULATIONS ARE LIKELY ACROSS THE
AREA...LATE FRIDAY MORNING/EARLY AFTERNOON THROUGH FRIDAY EVENING.
A STRONG ARCTIC COLD FRONT WILL PUSH THROUGH THE AREA FRIDAY
NIGHT INTO EARLY SATURDAY...BRINGING A MUCH COLDER/DRIER AIRMASS TO
THE REGION. VERY STRONG HIGH PRESSURE WILL BUILD IN FROM THE
NORTHWEST THROUGH THE WEEKEND. 850MB TEMPS WILL PLUMMET TO -15 TO
-20C BY SUNDAY WITH LOW LEVEL THICKNESS DROPPING INTO THE
1225-1240M RANGE...RESULTING IN VERY COLD TEMPERATURES THIS
WEEKEND. SOME RECORD LOW MAX VALUES WILL BE POSSIBLE. LOW LEVEL
THICKNESS VALUES SUPPORT HIGHS 35-40 DEGREES SAT...AND THEN UPPER
20S TO LOW 30S SUNDAY. OVERNIGHT LOWS...MID/UPPER TEENS TO LOW 20S
FOR BOTH SATURDAY AND SUNDAY NIGHTS. THE OUTER BANKS COULD SEE
SOME FLURRIES OR VERY LIGHT SNOW SHOWERS ON AND OFF SAT INTO SUN.
WIND CHILL VALUES IN THE SINGLE DIGITS LIKELY SAT NIGHT INTO
SUNDAY MORNING ACROSS THE REGION.
HIGH PRESSURE WILL SHIFT OFF THE COAST MONDAY AS NEXT SYSTEM
APPROACHES THE AREA. STRONG SHORTWAVE MOVING OUT OF THE CENTRAL
PLAINS WILL MOVE EASTWARD...INDUCING CYCLOGENESIS OFF THE SE
COAST MONDAY NIGHT AND TUE. SLIGHT MODEL DIFFERENCES CONTINUE
REGARDING THE TIMING...STRENGTH OF THE SHORTWAVE AND THEN SFC
LOW. WILL CONTINUE SC/LOW CHANCE POPS AT THIS TIME...WITH BEST
CHANCES MONDAY NIGHT AND TUESDAY. PRECIP COULD BEGIN AS -RA/-SN
MIX MONDAY MORNING BEFORE TRANSITIONING TO ALL RAIN. TEMPS LOOK
TO REBOUND AND RETURN TO NEAR CLIMO...HIGHS MON 40-50 DEGREES AND
TUE IN THE LOW/MID 50S.
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM /THROUGH 06Z THURSDAY/...
AS OF 1230 AM WEDNESDAY...HIGH CONFIDENCE OF VFR CONDITIONS
THROUGH TAF PERIOD. AC DECK WILL MOVE OFF COAST NEXT FEW HOURS
LEAVING MOSTLY CLR SKIES OVERNIGHT INTO EARLY MORNING...AND WEST
WINDS 5-10 MPH AND DRYING AIR MASS WILL PRECLUDE ANY FOG
DEVELOPMENT. ADDITIONAL SHRT WV ENERGY WILL RESULT IN SCT-BKN SCU
AND AC DEVELOPMENT LATE MORNING THROUGH AFTN WITH ANY CIGS ABV 3K
FT. CLOUDS DISSIPATING WITH LOSS OF HEATING THIS EVENING. WEST
WINDS WILL GUST TO 20 KT AGAIN LATE MORNING THROUGH AFTN.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 3 AM WED...PRED VFR CONDITIONS EXPECTED THU AND THU NIGHT.
WESTERLY WIND GUSTS TO 25KT THU AFTERNOON. SUB-VFR CONDITIONS WILL
BE LIKELY FRIDAY AS AN AREA OF LOW PRESSURE MOVES ALONG THE NC
COAST...BRINGING THE THREAT OF WINTRY PRECIPITATION TO THE
TERMINALS. A PERIOD OF LIGHT SNOW...MAYBE MIXED WITH LIGHT RAIN
AND SLEET WILL BE POSSIBLE LATE FRIDAY MORNING/EARLY AFTERNOON
INTO THE EARLY EVENING. PRED VFR CONDITIONS EXPECTED TO RETURN
LATE FRIDAY NIGHT AND CONTINUE THROUGH SUNDAY.
&&
.MARINE...
SHORT TERM /TONIGHT AND WEDNESDAY/...
AS OF 1230 AM WEDNESDAY...NO CHANGES WITH UPDATE.
/PREVIOUS DISCUSSION/
AS OF 900 PM TUESDAY...VERY ROUGH SEAS CONTINUE WITH 7 TO 10 FOOT
SEAS IN A COMBINATION OF 14-15 SECOND SWELL AND A SHORTER WIND
WAVE. THE LATEST 3KM HRRR AND RAP MODELS CONTINUE TO INDICATE
GUSTY WESTERLY WINDS AT 20 TO 25 KNOTS WITH GUSTS TO 30 KNOTS OVER
THE COASTAL WATERS AND PAMLICO SOUND TONIGHT INTO WEDNESDAY. NO
CHANGES TO THE ADVISORIES AT THIS TIME. WITH THE OFFSHORE
FLOW...SEAS SHOULD SUBSIDE ON WEDNESDAY...BUT WILL STILL REMAIN
WELL ABOVE SMALL CRAFT ADVISORY CRITERIA.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 3 AM WED...UNSETTLED BOATING CONDITIONS EXPECTED FOR MOST OF
THE PERIOD. HIGH PRESSURE WILL BUILD IN FROM THE NW THU AND FRI.
GUSTY WNW WINDS 15-25KT AND ELEVATED SEAS WILL START OFF THU...BUT
SHOULD BE GRADUALLY SUBSIDING THROUGH THE DAY. COULD SEE SEAS DROP
BELOW 6FT BY THU EVENING. AN AREA OF LOW PRESSURE WILL MOVE ALONG
THE NC COAST FRIDAY...WHILE STILL SOME UNCERTAINTY REGARDING THE
TRACK AND STRENGTH OF THE LOW, INCREASED WINDS SLIGHTLY FOR
FRI. THOUGH WILL KEEP AOB 15KT WITH SEAS 2-4FT. EXPECT STRONGER
WINDS LATE FRI AND FRI NIGHT ON THE BACKSIDE OF THE LOW AND AHEAD
OF THE APPROACHING FRONT. A STRONG ARCTIC FRONT WILL MOVE THROUGH
THE WATERS FRIDAY NIGHT INTO EARLY SATURDAY. SCA CONDITIONS
EXPECTED TO RE-DEVELOP FRIDAY NIGHT AND CONTINUE THROUGH SUNDAY.
NW WINDS WILL INCREASE TO 20-30KT WITH SEAS BUILDING TO 5-9FT.
WINDS WILL PEAK SAT NIGHT AND EARLY SUNDAY MORNING...WITH GALE
FORCE WIND GUSTS POSSIBLE.
&&
.TIDES/COASTAL FLOODING...
AS OF 335 PM TUESDAY...LATEST PREDICTED WATER LEVEL DEPARTURES
DURING THE HIGH TIDE TONIGHT AND AGAIN AROUND MID-MORNING ON
WEDNESDAY ARE AROUND 3 FEET...DOWN A BIT FROM THIS MORNING`S TIDE
WHICH PRODUCED SOME MINOR TO MODERATE COASTAL FLOODING. EARLIER
ISSUED A COASTAL FLOOD ADVISORY FOR THE OUTER BANKS TO RUN THROUGH
EARLY AFTERNOON WEDNESDAY TO ACCOUNT FOR ANY ADDITIONAL OCEAN
OVERWASH AND BEACH EROSION THAT MAY OCCUR AROUND THE NEXT TWO HIGH
TIDES.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...COASTAL FLOOD ADVISORY UNTIL NOON EST TODAY FOR NCZ103-104.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EST THURSDAY FOR AMZ135.
SMALL CRAFT ADVISORY UNTIL 7 AM EST FRIDAY FOR AMZ150-152-154-
156-158.
&&
$$
SYNOPSIS...CTC/CQD
NEAR TERM...JME/CTC/JBM
SHORT TERM...CTC
LONG TERM...CQD
AVIATION...JBM/CQD
MARINE...JME/CTC/JBM/CQD
TIDES/COASTAL FLOODING...MHX
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1259 AM EST WED FEB 10 2016
.SYNOPSIS...
ARCTIC HIGH PRESSURE WILL BUILD IN FROM THE NORTHWEST TONIGHT
THROUGH EARLY FRIDAY. AN ARCTIC COLD FRONT WILL MOVE THROUGH THE
AREA FRIDAY NIGHT FOLLOWED BY THE A BLAST OF VERY COLD AIR FOR THE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1230 AM WEDNESDAY...ADKUSTED SKY COVER FCST FOR MORE
CLEARING OVERNIGHT WITH MINOR CHANGES TO HOURLY TEMP/DEW PT GRIDS.
AC DECK HAS SPREAD ACROSS MOST OF SRN 2/3 OF AREA AND PROGGED TO
MOVE OFF COAST NEXT 2-3 HOURS. MOSTLY CLEAR SKIES EXPECTED ACROSS
AREA REST OF NIGHT AFTER THIS CLOUDINESS PUSHES OFFSHORE. DEW PTS
ARE DROPPING INTO TEENS INLAND BUT WESTERLY WINDS 5-15 MPH WILL
KEEP ATMOS MIXED OVERNIGHT...AND HOLD MIN TEMPS IN UPR 20S INLAND
AND LOW-MID 30S COAST.
/PREVIOUS DISCUSSION/
AS OF 900 PM TUESDAY...YET ANOTHER IN A SERIES OF MID LEVEL
SHORTWAVES SWINGING ACROSS THE REGION IN THE DEEPLY CYCLONIC FLOW
ALOFT CONTINUES TO PRODUCE SCATTERED SHOWERS THIS EVENING. THE
HIGH RESOLUTION GUIDANCE HANGS ON TO THESE SHOWERS UNTIL AROUND
03Z THEN INDICATES DRYING WITH SKIES CLEARING AFTER 06Z. THERE
WILL BE ENOUGH OF A GRADIENT OVERNIGHT TO SUSTAIN WESTERLY WINDS 5
TO 10 MPH INLAND AND 15 TO 25 MPH COAST. THESE WINDS COUPLED WITH
TEMPERATURES PROJECTED TO FALL INTO THE MID AND UPPER 20S INLAND
AND LOW 30S OUTER BANKS WILL ADD AN ADDITIONAL CHILL TO THE AIR.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/...
AS OF 315 PM TUESDAY...FORECAST SOUNDINGS SHOWING SOME LINGERING
MOISTURE BETWEEN 750 AND 850 MB WEDNESDAY AFTERNOON...WHICH SHOULD
YIELD PARTLY CLOUDY SKIES. ANOMALOUSLY LOW THICKNESSES SHOULD LEAD
TO A CHILLY DAY WITH HIGHS GENERALLY IN THE LOWER 40S WITH WEST
WINDS 10 TO 15 MPH WITH A FEW HIGHER GUSTS MAKING IT FEEL EVEN
COLDER.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
BELOW NORMAL TEMPERATURES THROUGH EARLY NEXT WEEK...WITH ARCTIC
AIRMASS MOVING INTO EASTERN NC THIS WEEKEND.
WEDNESDAY NIGHT INTO THURSDAY... HEIGHTS ALOFT WILL BEGIN TO
RISE...BUT LONGWAVE TROUGH WILL REMAIN DOMINANT ACROSS THE
EASTERN HALF. 850MB TEMPERATURE STILL REMAINS BELOW
AVERAGE...THEREFORE LEADING TO ANOTHER COLD DAY WITH HIGHS IN THE
MID/UPPER 30S UNDER SUNNY SKIES. THURSDAY NIGHT, EXPECT LOWS IN
THE LOW 20S.
FRIDAY AND SATURDAY...ANOTHER SHORTWAVE ENERGY WILL DROP DOWN FROM
CANADA FRIDAY AND FRIDAY NIGHT...LEADING TO RE-AMPLIFYING THE
UPPER LEVEL TROUGH OVER THE EASTERN HALF U.S. AND BRINGING EVEN
COLDER ARCTIC AIRMASS INTO THE SOUTHEAST REGION OVER THE WEEKEND.
BOTH THE 09/12Z GFS AND 09/12Z ECMWF IS HAVING A BETTER AGREEMENT
WITH THE NEXT POTENTIAL WEATHER MAKER FOR FRIDAY INTO LATE FRIDAY
NIGHT. BOTH MODELS SHOW A STRONG FORCING AS SHORTWAVE MOVES THROUGH
WHILE SFC HIGH BUILDS OVER THE AREA AND SFC LOW DEVELOP OFF THE
COAST. THE SHORTWAVE COULD PROVIDE ENOUGH LIFT TO SEE SOME -RA/-SN
SHOWERS. WILL CONTINUE WITH 20 POPS OF -RA/-SN MIX...THOUGH NOT
EXPECTING LITTLE IF ANY ACCUMULATIONS. HIGHS FRIDAY IN THE LOW 40S.
SATURDAY AND SUNDAY...A SECONDARY COLD FRONT WILL PUSH THROUGH THE
AREA FRIDAY NIGHT INTO EARLY SATURDAY...BRINGING EVEN COLDER/DRIER
AIRMASS INTO THE REGION.VERY STRONG HIGH PRESSURE WILL BUILD INTO
THE REGION FROM THE NORTHWEST. THE 850MB TEMPS WILL PLUMMET BY
SUNDAY BTW -20C TO -15C WITH LOW LEVEL THICKNESS DROPPING INTO THE
1225-1240M RANGE. THIS WILL BRING VERY COLD TEMPERATURES ACROSS THE
AREA...WITH HIGH STRUGGLING TO REACH FREEZING ON SUNDAY. SATURDAY
HIGHS...UPPER 30S/LOW 40S AND SUNDAY`S HIGHS IN THE LOW 30S.
OVERNIGHT LOWS...MID/UPPER TEENS TO LOW 20S FOR BOTH SATURDAY SUNDAY
NIGHT.
MONDAY AND TUESDAY...THE LONG WAVE TROUGH AXIS AND SFC HIGH PRESSURE
WILL SHIFT OFFSHORE ON MONDAY AS THE NEXT SHORTWAVE COMES IN FROM
THE CENTRAL PLAINS AND DEVELOPING A SFC LOW DEVELOP OFF THE CAROLINA
COAST. WILL CONTINUE THE MENTION 20% POP FOR RAIN...MONDAY AFTERNOON
AND TUESDAY... AS THE SFC LOW WILL BE CLOSE TO THE COAST.
TEMPERATURES WILL BEGIN TO REBOUND MONDAY AS HIGHS ARE EXPECTED TO
REACH INTO THE 40S MONDAY AND LOW 50S TUESDAY.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM /THROUGH 06Z THURSDAY/...
AS OF 1230 AM WEDNESDAY...HIGH CONFIDENCE OF VFR CONDITIONS
THROUGH TAF PERIOD. AC DECK WILL MOVE OFF COAST NEXT FEW HOURS
LEAVING MOSTLY CLR SKIES OVERNIGHT INTO EARLY MORNING...AND WEST
WINDS 5-10 MPH AND DRYING AIR MASS WILL PRECLUDE ANY FOG
DEVELOPMENT. ADDITIONAL SHRT WV ENERGY WILL RESULT IN SCT-BKN SCU
AND AC DEVELOPMENT LATE MORNING THROUGH AFTN WITH ANY CIGS ABV 3K
FT. CLOUDS DISSIPATING WITH LOSS OF HEATING THIS EVENING. WEST
WINDS WILL GUST TO 20 KT AGAIN LATE MORNING THROUGH AFTN.
LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 330 PM TUES...MAINLY VFR CONDITIONS WILL PREVAIL THROUGH
SUNDAY WITH WESTERLY FLOW 5 TO 15 KNOTS. MVFR CONDITIONS ARE
POSSIBLE FOR FRIDAY/FRIDAY EVENING WITH ISOLATED RAIN/SNOW SHOWERS.
COLD FRONT WILL PUSH THROUGH FRIDAY NIGHT INTO SATURDAY WITH STRONG
HIGH PRESSURE BUILD BEHIND IT. NORTHWEST WINDS 10-15 KNOTS WITH
GUSTS UP TO 20 KNOTS FOR THURSDAY AND SATURDAY.
&&
.MARINE...
SHORT TERM /TONIGHT AND WEDNESDAY/...
AS OF 1230 AM WEDNESDAY...NO CHANGES WITH UPDATE.
/PREVIOUS DISCUSSION/
AS OF 900 PM TUESDAY...VERY ROUGH SEAS CONTINUE WITH 7 TO 10 FOOT
SEAS IN A COMBINATION OF 14-15 SECOND SWELL AND A SHORTER WIND
WAVE. THE LATEST 3KM HRRR AND RAP MODELS CONTINUE TO INDICATE
GUSTY WESTERLY WINDS AT 20 TO 25 KNOTS WITH GUSTS TO 30 KNOTS OVER
THE COASTAL WATERS AND PAMLICO SOUND TONIGHT INTO WEDNESDAY. NO
CHANGES TO THE ADVISORIES AT THIS TIME. WITH THE OFFSHORE
FLOW...SEAS SHOULD SUBSIDE ON WEDNESDAY...BUT WILL STILL REMAIN
WELL ABOVE SMALL CRAFT ADVISORY CRITERIA.
LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 330 PM TUES...POOR BOATING CONDITIONS WILL CONTINUE THROUGH
MUCH OF THE PERIOD WITH WEST/NORTHWEST WINDS 15 TO 25 KNOTS AND
ELEVATED SEAS OF 6 FT OR HIGHER. SMALL CRAFT ADVISORY CONDITIONS ARE
EXPECTED TO CONTINUE THROUGH THURSDAY NIGHT FOR ALL THE COASTAL
WATERS AND PAMLICO SOUND. THERE WILL BE A BREAK ON FRIDAY AS WINDS
AND SEAS SUBSIDE AS HIGH PRESSURE BUILDS...WITH NW WINDS 10-15 KNOTS
AND 2 TO 4 FT. SEAS AND WINDS ARE EXPECTED TO INCREASE AS ANOTHER
STRONG COLD FRONT TO PUSH THROUGH THE COASTAL WATERS...EXPECT NW
WINDS 20-30 KTS AND SEAS BUILDING 5-8 FT. GALE FORCE WIND GUSTS
WILL BE POSSIBLE FOR SATURDAY AFTERNOON/EVENING.
&&
.TIDES/COASTAL FLOODING...
AS OF 335 PM TUESDAY...LATEST PREDICTED WATER LEVEL DEPARTURES
DURING THE HIGH TIDE TONIGHT AND AGAIN AROUND MID-MORNING ON
WEDNESDAY ARE AROUND 3 FEET...DOWN A BIT FROM THIS MORNING`S TIDE
WHICH PRODUCED SOME MINOR TO MODERATE COASTAL FLOODING. EARLIER
ISSUED A COASTAL FLOOD ADVISORY FOR THE OUTER BANKS TO RUN THROUGH
EARLY AFTERNOON WEDNESDAY TO ACCOUNT FOR ANY ADDITIONAL OCEAN
OVERWASH AND BEACH EROSION THAT MAY OCCUR AROUND THE NEXT TWO HIGH
TIDES.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...COASTAL FLOOD ADVISORY UNTIL NOON EST TODAY FOR NCZ103-104.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EST THURSDAY FOR AMZ135.
SMALL CRAFT ADVISORY UNTIL 7 AM EST FRIDAY FOR AMZ150-152-154-
156-158.
&&
$$
SYNOPSIS...CTC
NEAR TERM...JME/CTC/JBM
SHORT TERM...CTC
LONG TERM...BM
AVIATION...JBM/BM
MARINE...JME/CTC/JBM/BM
TIDES/COASTAL FLOODING...MHX
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1241 PM CST WED FEB 10 2016
.UPDATE...
ISSUED AT 1238 PM CST WED FEB 10 2016
ACCUMULATING SNOW HAS ENDED ACROSS MOST OF THE CWFA. DID ADD A
FLURRY MENTION IN E ND THROUGH THE AFTERNOON WITH LINGERING ECHOS
ON RADAR ANS A FEW 5 TO 7 MILE VSBY REPORTS. NO OTHER CHANGES WERE
MADE.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 311 AM CST WED FEB 10 2016
SNOW AMOUNTS TODAY AND TEMPERATURES THROUGH THE PERIOD WILL BE THE
MAIN FORECAST CHALLENGES FOR THE SHORT TERM.
NORTHWEST FLOW ALOFT CONTINUES WITH THE RAP ANALYSIS SHOWING A 150
KT JET STREAK DIGGING INTO THE RED RIVER VALLEY. SNOW HAS BEEN
FALLING SINCE BEFORE 06Z IN OUR WESTERN CWA...WITH AUTOMATED SITES
SHOWING AROUND 0.06 TO 0.08 INCHES OF LIQUID SO FAR. THE SNOW BAND
LINES UP WELL WITH THE UPPER DIVERGENCE FROM THE JET AS WELL AS
700MB FRONTOGENESIS SEEN ON SPC MESO PAGE. VIS HAS BEEN MOSTLY IN
THE 2 TO 5SM RANGE ALTHOUGH A FEW SITES HAVE BEEN DOWN TO 1SM AT
TIMES. THE MODELS HAVE FRONTOGENESIS CONTINUING UNTIL AROUND 18Z
TODAY...SO THINK WE SHOULD HAVE PRETTY DECENT BAND OF ACCUMULATING
SNOW IN THE WESTERN COUNTIES. SOME OF THE RECENT RUNS HAVE BEEN
BACKING OFF ON QPF...BUT WILL KEEP THE 3 INCHES ACROSS THE WEST
FOR NOW AND SEE HOW THINGS ARE AT 12Z. DID CUT THE AMOUNTS IN RED
RIVER VALLEY WHICH WILL BE ON THE EASTERN EDGE OF THE PRECIP
BAND.
TEMPS THIS AFTERNOON SHOULD BE SOMEWHAT SIMILAR TO
YESTERDAY...WITH HIGHEST READINGS IN THE SOUTHWESTERN COUNTIES AND
COLDER TEMPS EVEN WITH MORE SUN IN THE NORTHEAST WHICH WILL START
OUT WELL BELOW ZERO THIS MORNING. CLOUDS WILL HAVE A LARGE IMPACT
ON TEMPS TONIGHT. ANOTHER WEAK SHORTWAVE COMING DOWN THE NORTHWEST
FLOW WILL START MOVING INTO WESTERN ND...SO OUR WEST SHOULD BE
CLOUDY EVEN AS THE PRECIP STAYS OUT OF THE CWA. THE NORTHEAST WILL
AGAIN HAVE VERY LIGHT WINDS AND MOSTLY CLEAR SKIES...SO GETTING
DOWN INTO THE 10 TO 15 BELOW RANGE WILL AGAIN BE POSSIBLE. THE
CLOUDY WEST AND MORE SUNNY EAST SHOULD CONTINUE INTO THURSDAY WITH
HIGHS AGAIN SHOWING A DECENT GRADIENT OF SINGLE DIGITS TO LOW 20S.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 311 AM CST WED FEB 10 2016
THURSDAY NIGHT THROUGH FRIDAY NIGHT...NORTHWESTERLY FLOW ALOFT
CONTINUES AS THE UPPER RIDGE AXIS MOVES INTO THE ROCKIES BY LATE
FRIDAY. A WEAK SHORTWAVE WILL CONTINUE TO DIG DOWN THROUGH THE
NORTHERN PLAINS THURSDAY NIGHT...ALTHOUGH THE MODELS HAVE BEEN
TRENDING A BIT FURTHER WEST WITH THIS SYSTEM. WILL KEEP SOME LOW
POPS IN THE SOUTHWESTERN COUNTIES BUT THINK IMPACTS WILL BE
MINIMAL. OF GREATER NOTE IS A SURGE OF COLDER AIR COMING DOWN
DURING THE PERIOD. THE MORE THAN 1040MB HIGH DIGGING INTO THE
NORTHERN PLAINS WILL HELP HIGHS ON FRIDAY BE A GOOD 10 DEGREES
COLDER THAN THURSDAY. DEPENDING ON CLOUD COVER...MUCH OF THE CWA
WILL DROP INTO THE 10 TO 20 BELOW RANGE FRIDAY NIGHT WITH LIGHT
WINDS...AND SOME SPOTS IN THE EAST COULD BE EVEN COLDER.
SATURDAY THROUGH TUESDAY...
MODELS INITIALIZED WELL AND IN GENERAL AGREEMENT THIS RUN. NW FLOW
ALOFT WILL PERSIST THRU THE END OF THE PERIOD...WITH A FEW WAVES
CROSSING THE FORECAST AREA. FOR SATURDAY...SFC HIGH PRESSURE
RETREATS WITH RETURN FLOW AND WARMER TEMPS SPREADING ACROSS THE
REGION. A WAVE PROGRESSES EAST ON SATURDAY EVENING BRINGING ANOTHER
ROUND OF MEASURABLE PRECIPITATION. AFTER A SLIGHT COOL DOWN BEHIND
THE SYSTEM...ANOTHER WAVE WILL CROSS THE AREA BY THE END OF THE
PERIOD...WITH MORE CHANCES FOR PRECIPITATION. TEMPERATURES ARE
EXPECTED TO REBOUND BACK TO NEAR NORMAL VALUES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1238 PM CST WED FEB 10 2016
EXPECT CLOUDS TO PERSIST IN ALL BUT THE FAR EAST...WITH GENERAL MVFR
CIGS AND AT TIMES VFR CIGS. WINDS WILL BE LIGHT...UNDER 10KT FROM AN
EASTERLY DIRECTION THROUGH THE PERIOD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JK
SHORT TERM...JR
LONG TERM...JR/HOPKINS
AVIATION...DK
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
934 AM CST WED FEB 10 2016
.UPDATE...
ISSUED AT 929 AM CST WED FEB 10 2016
SNOW INTENSITIES STARTING TO DIMINISH WITH VSBYS IMPROVING ACROSS
THE DEVILS LAKE BASIN AND CENTRAL VALLEY AS STRONGEST RADAR
RETURNS ARE NOW IN SOUTHEASTERN ND. MINIMAL CHANGES NEEDED FOR
THE UPDATE WITH A TWEAK TO THE POPS COVERAGE TO MATCH CURRENT
TRENDS. ENDING TIME FOR THE ACCUMULATING SNOW IN THE NEXT COUPLE
HOURS IS ON TRACK WITH -SN LINGERING ACROSS E ND INTO THE EARLY
AFTERNOON.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 311 AM CST WED FEB 10 2016
SNOW AMOUNTS TODAY AND TEMPERATURES THROUGH THE PERIOD WILL BE THE
MAIN FORECAST CHALLENGES FOR THE SHORT TERM.
NORTHWEST FLOW ALOFT CONTINUES WITH THE RAP ANALYSIS SHOWING A 150
KT JET STREAK DIGGING INTO THE RED RIVER VALLEY. SNOW HAS BEEN
FALLING SINCE BEFORE 06Z IN OUR WESTERN CWA...WITH AUTOMATED SITES
SHOWING AROUND 0.06 TO 0.08 INCHES OF LIQUID SO FAR. THE SNOW BAND
LINES UP WELL WITH THE UPPER DIVERGENCE FROM THE JET AS WELL AS
700MB FRONTOGENESIS SEEN ON SPC MESO PAGE. VIS HAS BEEN MOSTLY IN
THE 2 TO 5SM RANGE ALTHOUGH A FEW SITES HAVE BEEN DOWN TO 1SM AT
TIMES. THE MODELS HAVE FRONTOGENESIS CONTINUING UNTIL AROUND 18Z
TODAY...SO THINK WE SHOULD HAVE PRETTY DECENT BAND OF ACCUMULATING
SNOW IN THE WESTERN COUNTIES. SOME OF THE RECENT RUNS HAVE BEEN
BACKING OFF ON QPF...BUT WILL KEEP THE 3 INCHES ACROSS THE WEST
FOR NOW AND SEE HOW THINGS ARE AT 12Z. DID CUT THE AMOUNTS IN RED
RIVER VALLEY WHICH WILL BE ON THE EASTERN EDGE OF THE PRECIP
BAND.
TEMPS THIS AFTERNOON SHOULD BE SOMEWHAT SIMILAR TO
YESTERDAY...WITH HIGHEST READINGS IN THE SOUTHWESTERN COUNTIES AND
COLDER TEMPS EVEN WITH MORE SUN IN THE NORTHEAST WHICH WILL START
OUT WELL BELOW ZERO THIS MORNING. CLOUDS WILL HAVE A LARGE IMPACT
ON TEMPS TONIGHT. ANOTHER WEAK SHORTWAVE COMING DOWN THE NORTHWEST
FLOW WILL START MOVING INTO WESTERN ND...SO OUR WEST SHOULD BE
CLOUDY EVEN AS THE PRECIP STAYS OUT OF THE CWA. THE NORTHEAST WILL
AGAIN HAVE VERY LIGHT WINDS AND MOSTLY CLEAR SKIES...SO GETTING
DOWN INTO THE 10 TO 15 BELOW RANGE WILL AGAIN BE POSSIBLE. THE
CLOUDY WEST AND MORE SUNNY EAST SHOULD CONTINUE INTO THURSDAY WITH
HIGHS AGAIN SHOWING A DECENT GRADIENT OF SINGLE DIGITS TO LOW 20S.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 311 AM CST WED FEB 10 2016
THURSDAY NIGHT THROUGH FRIDAY NIGHT...NORTHWESTERLY FLOW ALOFT
CONTINUES AS THE UPPER RIDGE AXIS MOVES INTO THE ROCKIES BY LATE
FRIDAY. A WEAK SHORTWAVE WILL CONTINUE TO DIG DOWN THROUGH THE
NORTHERN PLAINS THURSDAY NIGHT...ALTHOUGH THE MODELS HAVE BEEN
TRENDING A BIT FURTHER WEST WITH THIS SYSTEM. WILL KEEP SOME LOW
POPS IN THE SOUTHWESTERN COUNTIES BUT THINK IMPACTS WILL BE
MINIMAL. OF GREATER NOTE IS A SURGE OF COLDER AIR COMING DOWN
DURING THE PERIOD. THE MORE THAN 1040MB HIGH DIGGING INTO THE
NORTHERN PLAINS WILL HELP HIGHS ON FRIDAY BE A GOOD 10 DEGREES
COLDER THAN THURSDAY. DEPENDING ON CLOUD COVER...MUCH OF THE CWA
WILL DROP INTO THE 10 TO 20 BELOW RANGE FRIDAY NIGHT WITH LIGHT
WINDS...AND SOME SPOTS IN THE EAST COULD BE EVEN COLDER.
SATURDAY THROUGH TUESDAY...
MODELS INITIALIZED WELL AND IN GENERAL AGREEMENT THIS RUN. NW FLOW
ALOFT WILL PERSIST THRU THE END OF THE PERIOD...WITH A FEW WAVES
CROSSING THE FORECAST AREA. FOR SATURDAY...SFC HIGH PRESSURE
RETREATS WITH RETURN FLOW AND WARMER TEMPS SPREADING ACROSS THE
REGION. A WAVE PROGRESSES EAST ON SATURDAY EVENING BRINGING ANOTHER
ROUND OF MEASURABLE PRECIPITATION. AFTER A SLIGHT COOL DOWN BEHIND
THE SYSTEM...ANOTHER WAVE WILL CROSS THE AREA BY THE END OF THE
PERIOD...WITH MORE CHANCES FOR PRECIPITATION. TEMPERATURES ARE
EXPECTED TO REBOUND BACK TO NEAR NORMAL VALUES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 657 AM CST WED FEB 10 2016
VFR CONDITIONS CONTINUE AT ALL TAF SITES EXCEPT KDVL WHICH IS
STILL 1SM WITH CIGS IN THE 9000-1300 FT RANGE. THINK THAT
CONDITIONS SHOULD START TO IMPROVE AT KDVL IN THE NEXT FEW HOURS
AS THE SNOW BAND MOVES OFF. KGFK AND KFAR HAVE BEEN REPORTING SOME
FLURRIES AND HAVE VIS IN THE 5-6SM RANGE ALTHOUGH CIGS ARE STILL
IN THE VFR RANGE. EXPECT THE LOWERED VIS TO NOT LAST VERY LONG AS
THE SNOW BAND WILL BE SOUTH OF KGFK BY MID MORNING AND KFAR BY
18Z. SOME MVFR CIGS MAY HANG AROUND KDVL BUT OTHER SITES SHOULD BE
VFR FOR THE REST OF THE PERIOD. WINDS WILL BE OUT OF THE EAST
SOUTHEAST AT ABOUT 10 KTS EARLY IN THE PERIOD BUT BECOME LIGHT AND
VARIABLE BY THIS AFTERNOON.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JK
SHORT TERM...JR
LONG TERM...JR/HOPKINS
AVIATION...JR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
657 AM CST WED FEB 10 2016
.UPDATE...
ISSUED AT 657 AM CST WED FEB 10 2016
THE MAIN ISSUE IS SNOW AMOUNTS. REPORTS HAVE BEEN SPARSE...BUT GOT
ONE OF 3 INCHES IN DEVILS LAKE. THIS FITS WITH THE LOWER END OF
THE SNOW TOTAL RANGE ON RADAR ESTIMATE. ADJUSTED GRIDS FOR CURRENT
SNOW AMOUNTS. BAND IS SHOWING SIGNS OF WEAKENING ON THE NORTH END
AND THINK SNOW WILL BE ENDING SOON THERE WHILE THE
SHEYENNE/FAR SOUTHERN RED BASINS WILL SEE ANOTHER INCH OR TWO. ALL
THE SHORT RANGE MODELS HAVE PRECIP PRETTY MUCH ENDING BY 18Z. WILL
KEEP THE SPS GOING AND UPDATE TOP NEWS FOR UPDATED WINDS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 311 AM CST WED FEB 10 2016
SNOW AMOUNTS TODAY AND TEMPERATURES THROUGH THE PERIOD WILL BE THE
MAIN FORECAST CHALLENGES FOR THE SHORT TERM.
NORTHWEST FLOW ALOFT CONTINUES WITH THE RAP ANALYSIS SHOWING A 150
KT JET STREAK DIGGING INTO THE RED RIVER VALLEY. SNOW HAS BEEN
FALLING SINCE BEFORE 06Z IN OUR WESTERN CWA...WITH AUTOMATED SITES
SHOWING AROUND 0.06 TO 0.08 INCHES OF LIQUID SO FAR. THE SNOW BAND
LINES UP WELL WITH THE UPPER DIVERGENCE FROM THE JET AS WELL AS
700MB FRONTOGENESIS SEEN ON SPC MESO PAGE. VIS HAS BEEN MOSTLY IN
THE 2 TO 5SM RANGE ALTHOUGH A FEW SITES HAVE BEEN DOWN TO 1SM AT
TIMES. THE MODELS HAVE FRONTOGENESIS CONTINUING UNTIL AROUND 18Z
TODAY...SO THINK WE SHOULD HAVE PRETTY DECENT BAND OF ACCUMULATING
SNOW IN THE WESTERN COUNTIES. SOME OF THE RECENT RUNS HAVE BEEN
BACKING OFF ON QPF...BUT WILL KEEP THE 3 INCHES ACROSS THE WEST
FOR NOW AND SEE HOW THINGS ARE AT 12Z. DID CUT THE AMOUNTS IN RED
RIVER VALLEY WHICH WILL BE ON THE EASTERN EDGE OF THE PRECIP
BAND.
TEMPS THIS AFTERNOON SHOULD BE SOMEWHAT SIMILAR TO
YESTERDAY...WITH HIGHEST READINGS IN THE SOUTHWESTERN COUNTIES AND
COLDER TEMPS EVEN WITH MORE SUN IN THE NORTHEAST WHICH WILL START
OUT WELL BELOW ZERO THIS MORNING. CLOUDS WILL HAVE A LARGE IMPACT
ON TEMPS TONIGHT. ANOTHER WEAK SHORTWAVE COMING DOWN THE NORTHWEST
FLOW WILL START MOVING INTO WESTERN ND...SO OUR WEST SHOULD BE
CLOUDY EVEN AS THE PRECIP STAYS OUT OF THE CWA. THE NORTHEAST WILL
AGAIN HAVE VERY LIGHT WINDS AND MOSTLY CLEAR SKIES...SO GETTING
DOWN INTO THE 10 TO 15 BELOW RANGE WILL AGAIN BE POSSIBLE. THE
CLOUDY WEST AND MORE SUNNY EAST SHOULD CONTINUE INTO THURSDAY WITH
HIGHS AGAIN SHOWING A DECENT GRADIENT OF SINGLE DIGITS TO LOW 20S.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 311 AM CST WED FEB 10 2016
THURSDAY NIGHT THROUGH FRIDAY NIGHT...NORTHWESTERLY FLOW ALOFT
CONTINUES AS THE UPPER RIDGE AXIS MOVES INTO THE ROCKIES BY LATE
FRIDAY. A WEAK SHORTWAVE WILL CONTINUE TO DIG DOWN THROUGH THE
NORTHERN PLAINS THURSDAY NIGHT...ALTHOUGH THE MODELS HAVE BEEN
TRENDING A BIT FURTHER WEST WITH THIS SYSTEM. WILL KEEP SOME LOW
POPS IN THE SOUTHWESTERN COUNTIES BUT THINK IMPACTS WILL BE
MINIMAL. OF GREATER NOTE IS A SURGE OF COLDER AIR COMING DOWN
DURING THE PERIOD. THE MORE THAN 1040MB HIGH DIGGING INTO THE
NORTHERN PLAINS WILL HELP HIGHS ON FRIDAY BE A GOOD 10 DEGREES
COLDER THAN THURSDAY. DEPENDING ON CLOUD COVER...MUCH OF THE CWA
WILL DROP INTO THE 10 TO 20 BELOW RANGE FRIDAY NIGHT WITH LIGHT
WINDS...AND SOME SPOTS IN THE EAST COULD BE EVEN COLDER.
SATURDAY THROUGH TUESDAY...
MODELS INITIALIZED WELL AND IN GENERAL AGREEMENT THIS RUN. NW FLOW
ALOFT WILL PERSIST THRU THE END OF THE PERIOD...WITH A FEW WAVES
CROSSING THE FORECAST AREA. FOR SATURDAY...SFC HIGH PRESSURE
RETREATS WITH RETURN FLOW AND WARMER TEMPS SPREADING ACROSS THE
REGION. A WAVE PROGRESSES EAST ON SATURDAY EVENING BRINGING ANOTHER
ROUND OF MEASURABLE PRECIPITATION. AFTER A SLIGHT COOL DOWN BEHIND
THE SYSTEM...ANOTHER WAVE WILL CROSS THE AREA BY THE END OF THE
PERIOD...WITH MORE CHANCES FOR PRECIPITATION. TEMPERATURES ARE
EXPECTED TO REBOUND BACK TO NEAR NORMAL VALUES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 657 AM CST WED FEB 10 2016
VFR CONDITIONS CONTINUE AT ALL TAF SITES EXCEPT KDVL WHICH IS
STILL 1SM WITH CIGS IN THE 9000-1300 FT RANGE. THINK THAT
CONDITIONS SHOULD START TO IMPROVE AT KDVL IN THE NEXT FEW HOURS
AS THE SNOW BAND MOVES OFF. KGFK AND KFAR HAVE BEEN REPORTING SOME
FLURRIES AND HAVE VIS IN THE 5-6SM RANGE ALTHOUGH CIGS ARE STILL
IN THE VFR RANGE. EXPECT THE LOWERED VIS TO NOT LAST VERY LONG AS
THE SNOW BAND WILL BE SOUTH OF KGFK BY MID MORNING AND KFAR BY
18Z. SOME MVFR CIGS MAY HANG AROUND KDVL BUT OTHER SITES SHOULD BE
VFR FOR THE REST OF THE PERIOD. WINDS WILL BE OUT OF THE EAST
SOUTHEAST AT ABOUT 10 KTS EARLY IN THE PERIOD BUT BECOME LIGHT AND
VARIABLE BY THIS AFTERNOON.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...JR
LONG TERM...JR/HOPKINS
AVIATION...JR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
311 AM CST WED FEB 10 2016
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 311 AM CST WED FEB 10 2016
SNOW AMOUNTS TODAY AND TEMPERATURES THROUGH THE PERIOD WILL BE THE
MAIN FORECAST CHALLENGES FOR THE SHORT TERM.
NORTHWEST FLOW ALOFT CONTINUES WITH THE RAP ANALYSIS SHOWING A 150
KT JET STREAK DIGGING INTO THE RED RIVER VALLEY. SNOW HAS BEEN
FALLING SINCE BEFORE 06Z IN OUR WESTERN CWA...WITH AUTOMATED SITES
SHOWING AROUND 0.06 TO 0.08 INCHES OF LIQUID SO FAR. THE SNOW BAND
LINES UP WELL WITH THE UPPER DIVERGENCE FROM THE JET AS WELL AS
700MB FRONTOGENESIS SEEN ON SPC MESO PAGE. VIS HAS BEEN MOSTLY IN
THE 2 TO 5SM RANGE ALTHOUGH A FEW SITES HAVE BEEN DOWN TO 1SM AT
TIMES. THE MODELS HAVE FRONTOGENESIS CONTINUING UNTIL AROUND 18Z
TODAY...SO THINK WE SHOULD HAVE PRETTY DECENT BAND OF ACCUMULATING
SNOW IN THE WESTERN COUNTIES. SOME OF THE RECENT RUNS HAVE BEEN
BACKING OFF ON QPF...BUT WILL KEEP THE 3 INCHES ACROSS THE WEST
FOR NOW AND SEE HOW THINGS ARE AT 12Z. DID CUT THE AMOUNTS IN RED
RIVER VALLEY WHICH WILL BE ON THE EASTERN EDGE OF THE PRECIP
BAND.
TEMPS THIS AFTERNOON SHOULD BE SOMEWHAT SIMILAR TO
YESTERDAY...WITH HIGHEST READINGS IN THE SOUTHWESTERN COUNTIES AND
COLDER TEMPS EVEN WITH MORE SUN IN THE NORTHEAST WHICH WILL START
OUT WELL BELOW ZERO THIS MORNING. CLOUDS WILL HAVE A LARGE IMPACT
ON TEMPS TONIGHT. ANOTHER WEAK SHORTWAVE COMING DOWN THE NORTHWEST
FLOW WILL START MOVING INTO WESTERN ND...SO OUR WEST SHOULD BE
CLOUDY EVEN AS THE PRECIP STAYS OUT OF THE CWA. THE NORTHEAST WILL
AGAIN HAVE VERY LIGHT WINDS AND MOSTLY CLEAR SKIES...SO GETTING
DOWN INTO THE 10 TO 15 BELOW RANGE WILL AGAIN BE POSSIBLE. THE
CLOUDY WEST AND MORE SUNNY EAST SHOULD CONTINUE INTO THURSDAY WITH
HIGHS AGAIN SHOWING A DECENT GRADIENT OF SINGLE DIGITS TO LOW 20S.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 311 AM CST WED FEB 10 2016
THURSDAY NIGHT THROUGH FRIDAY NIGHT...NORTHWESTERLY FLOW ALOFT
CONTINUES AS THE UPPER RIDGE AXIS MOVES INTO THE ROCKIES BY LATE
FRIDAY. A WEAK SHORTWAVE WILL CONTINUE TO DIG DOWN THROUGH THE
NORTHERN PLAINS THURSDAY NIGHT...ALTHOUGH THE MODELS HAVE BEEN
TRENDING A BIT FURTHER WEST WITH THIS SYSTEM. WILL KEEP SOME LOW
POPS IN THE SOUTHWESTERN COUNTIES BUT THINK IMPACTS WILL BE
MINIMAL. OF GREATER NOTE IS A SURGE OF COLDER AIR COMING DOWN
DURING THE PERIOD. THE MORE THAN 1040MB HIGH DIGGING INTO THE
NORTHERN PLAINS WILL HELP HIGHS ON FRIDAY BE A GOOD 10 DEGREES
COLDER THAN THURSDAY. DEPENDING ON CLOUD COVER...MUCH OF THE CWA
WILL DROP INTO THE 10 TO 20 BELOW RANGE FRIDAY NIGHT WITH LIGHT
WINDS...AND SOME SPOTS IN THE EAST COULD BE EVEN COLDER.
SATURDAY THROUGH TUESDAY...
MODELS INITIALIZED WELL AND IN GENERAL AGREEMENT THIS RUN. NW FLOW
ALOFT WILL PERSIST THRU THE END OF THE PERIOD...WITH A FEW WAVES
CROSSING THE FORECAST AREA. FOR SATURDAY...SFC HIGH PRESSURE
RETREATS WITH RETURN FLOW AND WARMER TEMPS SPREADING ACROSS THE
REGION. A WAVE PROGRESSES EAST ON SATURDAY EVENING BRINGING ANOTHER
ROUND OF MEASURABLE PRECIPITATION. AFTER A SLIGHT COOL DOWN BEHIND
THE SYSTEM...ANOTHER WAVE WILL CROSS THE AREA BY THE END OF THE
PERIOD...WITH MORE CHANCES FOR PRECIPITATION. TEMPERATURES ARE
EXPECTED TO REBOUND BACK TO NEAR NORMAL VALUES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1139 PM CST TUE FEB 9 2016
WINDS CONTINUE TO LOOK WEAK FOR THE NEXT 24 HOURS. LATEST MODELS
KEEP ANY LIGHT SNOW OUT OF KFAR/KGFK...SO HAVE REMOVED THAT FROM
THE LATEST TAFS. THE BEST CHANCES FOR SNOW REMAIN AT KDVL...WHICH
COULD DROP THE VSBY THERE BELOW A MILE AT TIMES. WITH LITTLE OR NO
SNOW AT KGFK/KFAR...ALSO INCREASED THE CEILINGS. WORST CEILINGS
WILL ALSO BE WITH THE SNOW AT KDVL.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...JR
LONG TERM...JR/HOPKINS
AVIATION...GODON
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
645 AM EST WED FEB 10 2016
.SYNOPSIS...
LOW PRESSURE OVER LAKE ONTARIO WILL CONTINUE TO MOVE AWAY FROM THE
AREA. A REINFORCING COLD FRONT FROM THIS LOW WILL MOVE SOUTH
ACROSS THE LOCAL AREA LATE TODAY AND THIS EVENING. ANOTHER WAVE
OF LOW PRESSURE WILL MOVE SOUTH ACROSS THE GREAT LAKES FRIDAY.
ARCTIC HIGH PRESSURE WILL BUILD SLOWLY SOUTH ACROSS THE GREAT
LAKES OVER THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS EXPECTED THE SNOW ACTIVITY HAS DIMINISHED CONSIDERABLY SINCE
03Z. STILL SEEING SOME SCATTERED SNOW SHOWERS BUT ACCUMS SINCE
MIDNIGHT APPEAR TO BE UNDER AN INCH WITH STORM TOTALS MAINLY 1 TO
3 INCHES WITH PERHAPS A FEW 4 INCH AMOUNTS SO FAR. THE FIRST HALF
OF TODAY SHOULD SEE LITTLE CHANGE FROM THE CURRENT SITUATION WITH
SCATTERED SNOW SHOWERS TO THE EAST OF KCLE. DO EXPECT MORE
WIDESPREAD SNOW TO DEVELOP THIS AFTERNOON AS A SECONDARY COLD
FRONT DIVES SOUTHEAST ACROSS THE AREA. THE WINDS WILL BECOME
NORTHWEST AND SHOULD HELP PUSH THE SNOW INTO INTERIOR AREAS. THE
LATEST HRRR SHOWS THE SNOW BLOSSOMING AFTER 18Z OVER THE EASTERN
TWO THIRDS OF THE AREA. WILL GIVE MUCH OF THE AREA LIKELY OR
HIGHER POPS FOR THIS AFTERNOON. ACCUMS WILL BE SIMILAR TO THE PAST
COUPLE OF DAY WITH AN INCH OR TWO POSSIBLE MOST OF THE AREA WITH
HIGHER AMOUNTS IN THE SNOWBELT WHERE THE HEADLINES CONTINUE. THE
DAY CREW WILL HAVE TO WATCH EASTERN CUYAHOGA COUNTY TO MAKE SURE
THEY DON`T APPROACH ADVISORY TYPE SNOW AMOUNTS THIS AFTERNOON AND
EVENING. PLACES LIKE TRUMBULL AND MAHONING COUNTIES COULD SEE A
COUPLE OF INCHES BY 00Z AND ANOTHER INCH OR TWO TONIGHT. THIS IS
WAY BELOW ADVISORY CRITERIA OF 4 INCHES IN 12 HOURS SO SEE NO NEED
FOR A HEADLINE THERE EITHER. HAVE LOWERED FORECAST HIGHS FROM THE
PREVIOUS PACKAGE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE SNOW SHOWERS SHOULD GET GOING EARLY THIS EVENING AS SATURATED
AIR FINALLY REACHES THE PREFERRED SNOW GROWTH ZONE. THE GOOD
MOISTURE WILL BE FAIRLY SHORT LIVED SO EXPECTED THE WORST OF THE
EVENT TO BE TONIGHT. LAKE HURON EVENTUALLY GETS INTO THE ACT LATER
TONIGHT BUT BY THAT TIME THE GOOD SYNOPTIC MOISTURE WILL BE
PULLING AWAY. HAVE FINED TUNED THE SNOW TOTALS IN THE WARNING
STATEMENT THAT JUST WENT OUT. AGAIN...THE DAY CREW WILL HAVE TO
WATCH THE PERIPHERAL AREAS TO MAKE SURE ADDITIONAL ADVISORIES ARE
NOT NEEDED. RIDGING WILL OCCUR ON THURSDAY AND BY LATE IN THE DAY
THE SNOW SHOWERS SHOULD BE UP THE LAKE FROM THE LOCAL AREA.
WESTERN AREAS COULD SEE SOME BRIEF SNOW SHOWERS TONIGHT BUT THE
MAIN ACTIVITY WILL BE IN THE SNOWBELT. SOME CLEARING IN THE WEST
IN POSSIBLE ON THURSDAY.
ANOTHER FRONTAL SYSTEM WILL IMPACT THE AREA LATE FRIDAY INTO
SATURDAY. A TRUE ARCTIC AIRMASS IS EXPECTED BEHIND THE FRONT WITH
850 TEMPS POSSIBLE GETTING TO NEG 25 OR COLDER. THIS WILL BE THE
COLDEST AIRMASS OF THE YEAR. RIGHT NOW IT LOOKS LIKE WE COULD SEE
ANOTHER LAKE HURON FETCH OVER THE WEEKEND. WITH AN AIRMASS THIS
COLD THE ATMOSPHERE WILL LIKELY BE FAIRLY DRY. LATER SHIFTS WILL
NEED TO MONITOR THE SITUATION FOR ADDITIONAL HEADLINES. HAVE
CONTINUE WITH THE FRIGID TEMPS IN THE FORECAST. MUCH OF THE AREA
SHOULD GET BELOW ZERO ON SATURDAY NIGHT FOR THE FIRST TIME THIS
WINTER.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
THE FLOW ALOFT CONTINUES TO FEATURE A BIG RIDGE OUT WEST EARLY NEXT
WEEK. HEIGHTS RISE A BIT IN THE EAST BUT THE TROUGH IS PROGGED TO
REMAIN OVER THE EASTERN GREAT LAKES.
ARCTIC HIGH PRESSURE WILL SHIFT EAST OF THE FORECAST AREA ON SUNDAY.
HIGH CLOUDS WILL PROBABLY INCREASE IN THE AFTERNOON. TEMPERATURES
WILL START TO RECOVER AND TEMPS WILL PROBABLY CONTINUE TO GO UP
SUNDAY NIGHT.
THE MODELS CONTINUE TO DISAGREE ON MONDAY. THE GFS CONTINUES TO TAKE
A CLIPPER TYPE SYSTEM ACROSS THE GREAT LAKES WITH LIGHT AMOUNTS OF
PRECIP. IT DEVELOPS AN EAST COAST LOW BY TUESDAY. THE ECMWF HAS BEEN
TAKING A SOUTHERN LOW AND BOUNCING IT BETWEEN THE OHIO VALLEY AND
THE EAST COAST BUT ULTIMATELY DEVELOPING AN EAST COAST LOW. THE CMC
ALSO HAS A SOUTHERN LOW BUT IT STAYS PRETTY FAR SOUTH. IN ANY
CASE...THERE WOULD SEEM TO BE AT LEAST A CHANCE FOR SOME WARM
ADVECTION SNOW...JUST NO CONFIDENCE ON THE AMOUNTS/DURATION YET.
CLOUDS MAY LINGER THROUGH TUESDAY AND SOME LINGERING LIGHT PRECIP IS
POSSIBLE. ANOTHER WAVE IS PROGGED TO DEVELOP ACROSS THE UPPER
MIDWEST BY MIDWEEK AND TRACK TOWARD THE AREA. TEMPERATURES WILL HAVE
RECOVERED TO NEAR NORMAL BY THAT TIME.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
THE SURFACE TROUGH WILL DROP ACROSS THE AREA TODAY AND SNOW
SHOWERS WILL INCREASE IN COVERAGE AND INTENSITY. IFR VISIBILITIES
AND CEILINGS WILL OCCUR WITH THE HEAVIER SNOW SHOWERS. THE
MAJORITY OF THE SNOW SHOULD END ACROSS NORTHWEST OHIO THIS
AFTERNOON AS THE TROUGH MOVES THROUGH. ACROSS NORTHEAST OH AND
NORTHWEST PA LAKE EFFECT SNOW SHOWERS WILL CONTINUE INTO THURSDAY.
WEST WINDS WILL BECOME NORTHWEST AND GUSTY TODAY.
OUTLOOK...GENERALLY VFR LATE THURSDAY/THURSDAY NIGHT. NON VFR IN
SNOW SHOWERS FRIDAY INTO SATURDAY.
&&
.MARINE...
BRISK WINDS WILL BE COMMON ON LAKE ERIE FOR MUCH OF THE REMAINDER OF
THE WEEK BUT WIND SPEEDS WILL LIKELY REMAIN JUST BELOW GALE FORCE.
WEST TO SOUTHWEST WINDS WILL AVERAGE 20 TO 30 KNOTS AND BECOME
NORTHWEST TONIGHT AS ARCTIC HIGH PRESSURE BUILDS ACROSS THE GREAT
LAKES. SOME FREEZING SPRAY IS LIKELY BUT ACCRETION RATES SHOULD
REMAIN LIGHT TO MODERATE.
WINDS WILL BACK TO SOUTHWEST BY THURSDAY EVENING AHEAD OF THE NEXT
ARCTIC FRONT. THE ARCTIC COLD FRONT SHOULD CROSS THE LAKE BY FRIDAY
EVENING AND NORTHWEST WINDS WILL LIKELY INCREASE TO 30 KNOTS. HEAVY
FREEZING SPRAY IS POSSIBLE FRIDAY NIGHT AND SATURDAY.
HIGH PRESSURE WILL BUILD ACROSS LAKE ERIE BY SUNDAY AND WINDS
WILL LIGHTEN. WINDS WILL SHIFT TO SOUTH BY LATE SUNDAY AS THE HIGH
MOVES EAST OF THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...LAKE EFFECT SNOW ADVISORY UNTIL 4 PM EST THURSDAY FOR OHZ012-
089.
LAKE EFFECT SNOW WARNING UNTIL 4 PM EST THURSDAY FOR OHZ013-
014.
PA...LAKE EFFECT SNOW ADVISORY UNTIL 4 PM EST THURSDAY FOR PAZ001.
LAKE EFFECT SNOW WARNING UNTIL 4 PM EST THURSDAY FOR PAZ002-
003.
MARINE...NONE.
&&
$$
SYNOPSIS...KUBINA
NEAR TERM...KUBINA
SHORT TERM...KUBINA
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
356 AM EST WED FEB 10 2016
.SYNOPSIS...
LOW PRESSURE OVER LAKE ONTARIO WILL CONTINUE TO MOVE AWAY FROM THE
AREA. A REINFORCING COLD FRONT FROM THIS LOW WILL MOVE SOUTH
ACROSS THE LOCAL AREA LATE TODAY AND THIS EVENING. ANOTHER WAVE
OF LOW PRESSURE WILL MOVE SOUTH ACROSS THE GREAT LAKES FRIDAY.
ARCTIC HIGH PRESSURE WILL BUILD SLOWLY SOUTH ACROSS THE GREAT
LAKES OVER THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS EXPECTED THE SNOW ACTIVITY HAS DIMINISHED CONSIDERABLY SINCE
03Z. STILL SEEING SOME SCATTERED SNOW SHOWERS BUT ACCUMS SINCE
MIDNIGHT APPEAR TO BE UNDER AN INCH WITH STORM TOTALS MAINLY 1 TO
3 INCHES WITH PERHAPS A FEW 4 INCH AMOUNTS SO FAR. THE FIRST HALF
OF TODAY SHOULD SEE LITTLE CHANGE FROM THE CURRENT SITUATION WITH
SCATTERED SNOW SHOWERS TO THE EAST OF KCLE. DO EXPECT MORE
WIDESPREAD SNOW TO DEVELOP THIS AFTERNOON AS A SECONDARY COLD
FRONT DIVES SOUTHEAST ACROSS THE AREA. THE WINDS WILL BECOME
NORTHWEST AND SHOULD HELP PUSH THE SNOW INTO INTERIOR AREAS. THE
LATEST HRRR SHOWS THE SNOW BLOSSOMING AFTER 18Z OVER THE EASTERN
TWO THIRDS OF THE AREA. WILL GIVE MUCH OF THE AREA LIKELY OR
HIGHER POPS FOR THIS AFTERNOON. ACCUMS WILL BE SIMILAR TO THE PAST
COUPLE OF DAY WITH AN INCH OR TWO POSSIBLE MOST OF THE AREA WITH
HIGHER AMOUNTS IN THE SNOWBELT WHERE THE HEADLINES CONTINUE. THE
DAY CREW WILL HAVE TO WATCH EASTERN CUYAHOGA COUNTY TO MAKE SURE
THEY DON`T APPROACH ADVISORY TYPE SNOW AMOUNTS THIS AFTERNOON AND
EVENING. PLACES LIKE TRUMBULL AND MAHONING COUNTIES COULD SEE A
COUPLE OF INCHES BY 00Z AND ANOTHER INCH OR TWO TONIGHT. THIS IS
WAY BELOW ADVISORY CRITERIA OF 4 INCHES IN 12 HOURS SO SEE NO NEED
FOR A HEADLINE THERE EITHER. HAVE LOWERED FORECAST HIGHS FROM THE
PREVIOUS PACKAGE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE SNOW SHOWERS SHOULD GET GOING EARLY THIS EVENING AS SATURATED
AIR FINALLY REACHES THE PREFERRED SNOW GROWTH ZONE. THE GOOD
MOISTURE WILL BE FAIRLY SHORT LIVED SO EXPECTED THE WORST OF THE
EVENT TO BE TONIGHT. LAKE HURON EVENTUALLY GETS INTO THE ACT LATER
TONIGHT BUT BY THAT TIME THE GOOD SYNOPTIC MOISTURE WILL BE
PULLING AWAY. HAVE FINED TUNED THE SNOW TOTALS IN THE WARNING
STATEMENT THAT JUST WENT OUT. AGAIN...THE DAY CREW WILL HAVE TO
WATCH THE PERIPHERAL AREAS TO MAKE SURE ADDITIONAL ADVISORIES ARE
NOT NEEDED. RIDGING WILL OCCUR ON THURSDAY AND BY LATE IN THE DAY
THE SNOW SHOWERS SHOULD BE UP THE LAKE FROM THE LOCAL AREA.
WESTERN AREAS COULD SEE SOME BRIEF SNOW SHOWERS TONIGHT BUT THE
MAIN ACTIVITY WILL BE IN THE SNOWBELT. SOME CLEARING IN THE WEST
IN POSSIBLE ON THURSDAY.
ANOTHER FRONTAL SYSTEM WILL IMPACT THE AREA LATE FRIDAY INTO
SATURDAY. A TRUE ARCTIC AIRMASS IS EXPECTED BEHIND THE FRONT WITH
850 TEMPS POSSIBLE GETTING TO NEG 25 OR COLDER. THIS WILL BE THE
COLDEST AIRMASS OF THE YEAR. RIGHT NOW IT LOOKS LIKE WE COULD SEE
ANOTHER LAKE HURON FETCH OVER THE WEEKEND. WITH AN AIRMASS THIS
COLD THE ATMOSPHERE WILL LIKELY BE FAIRLY DRY. LATER SHIFTS WILL
NEED TO MONITOR THE SITUATION FOR ADDITIONAL HEADLINES. HAVE
CONTINUE WITH THE FRIGID TEMPS IN THE FORECAST. MUCH OF THE AREA
SHOULD GET BELOW ZERO ON SATURDAY NIGHT FOR THE FIRST TIME THIS
WINTER.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
THE FLOW ALOFT CONTINUES TO FEATURE A BIG RIDGE OUT WEST EARLY NEXT
WEEK. HEIGHTS RISE A BIT IN THE EAST BUT THE TROUGH IS PROGGED TO
REMAIN OVER THE EASTERN GREAT LAKES.
ARCTIC HIGH PRESSURE WILL SHIFT EAST OF THE FORECAST AREA ON SUNDAY.
HIGH CLOUDS WILL PROBABLY INCREASE IN THE AFTERNOON. TEMPERATURES
WILL START TO RECOVER AND TEMPS WILL PROBABLY CONTINUE TO GO UP
SUNDAY NIGHT.
THE MODELS CONTINUE TO DISAGREE ON MONDAY. THE GFS CONTINUES TO TAKE
A CLIPPER TYPE SYSTEM ACROSS THE GREAT LAKES WITH LIGHT AMOUNTS OF
PRECIP. IT DEVELOPS AN EAST COAST LOW BY TUESDAY. THE ECMWF HAS BEEN
TAKING A SOUTHERN LOW AND BOUNCING IT BETWEEN THE OHIO VALLEY AND
THE EAST COAST BUT ULTIMATELY DEVELOPING AN EAST COAST LOW. THE CMC
ALSO HAS A SOUTHERN LOW BUT IT STAYS PRETTY FAR SOUTH. IN ANY
CASE...THERE WOULD SEEM TO BE AT LEAST A CHANCE FOR SOME WARM
ADVECTION SNOW...JUST NO CONFIDENCE ON THE AMOUNTS/DURATION YET.
CLOUDS MAY LINGER THROUGH TUESDAY AND SOME LINGERING LIGHT PRECIP IS
POSSIBLE. ANOTHER WAVE IS PROGGED TO DEVELOP ACROSS THE UPPER
MIDWEST BY MIDWEEK AND TRACK TOWARD THE AREA. TEMPERATURES WILL HAVE
RECOVERED TO NEAR NORMAL BY THAT TIME.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
PERIODS OF SNOW WILL CONTINUE THROUGH THE TAF CYCLE AS LOW PRESSURE
OVER THE EASTERN GREAT LAKES SLOWLY EXITS TO THE EAST. WIDESPREAD
LIGHT SNOW ACROSS NE OHIO WILL SHIFT EASTWARD INTO PENNSYLVANIA
THROUGH 9-10Z. LIGHT TO MODERATE SNOW WILL CONTINUE FOR MUCH OF
THE NIGHT AT ERI BEFORE DECREASING WEDNESDAY MORNING. ELSEWHERE
EXPECT TO SEE SOME SCATTERED SNOW SHOWERS STARTING TO PICK BACK UP
AFTER 14Z WITH AN UPTICK IN INTENSITY ACROSS CENTRAL AND NORTHEAST
OHIO DURING THE AFTERNOON/EARLY EVENING. CEILINGS ACROSS THE AREA
WILL GENERALLY BE MVFR WITH IFR POSSIBLE IN THE HEAVIER SNOW
SHOWERS. WESTERLY WINDS MAY GUST TO AROUND 20 KNOTS AT TIMES AT
TOL/FDY/ERI.
OUTLOOK...NON VFR POSSIBLE THROUGH THE WEEK IN SNOW AND LOWER
CEILINGS AS A SERIES OF COLD FRONT WITH SNOW SHOWERS MOVE ACROSS
THE AREA. VFR MOST LIKELY THURSDAY NIGHT INTO FRIDAY MORNING AS A
RIDGE BUILDS IN BEFORE THE NEXT SYSTEM ARRIVES.
&&
.MARINE...
BRISK WINDS WILL BE COMMON ON LAKE ERIE FOR MUCH OF THE REMAINDER OF
THE WEEK BUT WIND SPEEDS WILL LIKELY REMAIN JUST BELOW GALE FORCE.
WEST TO SOUTHWEST WINDS WILL AVERAGE 20 TO 30 KNOTS AND BECOME
NORTHWEST TONIGHT AS ARCTIC HIGH PRESSURE BUILDS ACROSS THE GREAT
LAKES. SOME FREEZING SPRAY IS LIKELY BUT ACCRETION RATES SHOULD
REMAIN LIGHT TO MODERATE.
WINDS WILL BACK TO SOUTHWEST BY THURSDAY EVENING AHEAD OF THE NEXT
ARCTIC FRONT. THE ARCTIC COLD FRONT SHOULD CROSS THE LAKE BY FRIDAY
EVENING AND NORTHWEST WINDS WILL LIKELY INCREASE TO 30 KNOTS. HEAVY
FREEZING SPRAY IS POSSIBLE FRIDAY NIGHT AND SATURDAY.
HIGH PRESSURE WILL BUILD ACROSS LAKE ERIE BY SUNDAY AND WINDS
WILL LIGHTEN. WINDS WILL SHIFT TO SOUTH BY LATE SUNDAY AS THE HIGH
MOVES EAST OF THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...LAKE EFFECT SNOW ADVISORY UNTIL 4 PM EST THURSDAY FOR OHZ012-
089.
LAKE EFFECT SNOW WARNING UNTIL 4 PM EST THURSDAY FOR OHZ013-
014.
PA...LAKE EFFECT SNOW ADVISORY UNTIL 4 PM EST THURSDAY FOR PAZ001.
LAKE EFFECT SNOW WARNING UNTIL 4 PM EST THURSDAY FOR PAZ002-
003.
MARINE...NONE.
&&
$$
SYNOPSIS...KUBINA
NEAR TERM...KUBINA
SHORT TERM...KUBINA
LONG TERM...KOSARIK
AVIATION...KEC
MARINE...KOSARIK
AREA FORECAST DISCUSSION
NWS MEDFORD OR
1048 PM PST TUE FEB 9 2016
UPDATED AVIATION SECTION
.DISCUSSION...THE FORECAST WAS UPDATED TO RAISE POPS OVER THE
COASTAL WATERS AND ALONG THE COAST OVERNIGHT INTO WEDNESDAY
MORNING AS A FRONT WEAKENS AND DISSIPATES NEAR THE COAST. NEAR
TERM GUIDANCE LIKE THE HRRR AND THE RAP BOTH SHOW SOME LIGHT
PRECIPITATION NEAR THE COAST IN THE 12-18Z TIME FRAME (4-10AM), AS
DOES THE NEW 00Z NAM. THE FRONT IS SHALLOW WITH MOST OF THE DEEP
MOISTURE BELOW 700 MB. BUT, IT SHOULD BE ENOUGH TO SQUEEZE OUT
SOME LIGHT RAIN/DRIZZLE WITH A FEW HUNDREDTHS HERE AND THERE.
PRECIPITATION WON`T MAKE IT TOO FAR INLAND THOUGH...PROBABLY NO
MORE THAN 20 MILES (TO THE COAST RANGES). FOR THIS REASON, POPS
LESS THAN 10 PERCENT EXIST FROM ROSEBURG SOUTHWARD TO THE ILLINOIS
VALLEY AND EASTWARD. NO OTHER CHANGES WERE MADE THIS EVENING.
SPILDE
&&
.AVIATION...FOR THE 10/06Z TAF CYCLE...LIFR CIGS LIKELY RETURN TO
THE UMPQUA VALLEY OVERNIGHT INTO WEDNESDAY MORNING. A WEAK FRONT
WILL DISSIPATE AT THE COAST WEDNESDAY MORNING, BUT MAY BRIEFLY CAUSE
MVFR CIGS AND PERHAPS A LITTLE LIGHT RAIN OR DRIZZLE. THE REMAINDER
OF THE AREA WILL HAVE VFR. SPILDE
&&
.MARINE...UPDATED 730 PM PST TUE FEB 9 2016....SOUTH WINDS WILL
VEER TO SOUTHWEST THROUGH TONIGHT AS A WEAKENING FRONT APPROACHES.
THIS FRONT WILL MOVE IN VERY EARLY WEDNESDAY MORNING...BRINGING A
CHANCE FOR LIGHT RAIN/DRIZZLE. ANOTHER WEAK WARM FRONT WILL COME
IN FROM THE SOUTH INTO THE MARINE WATERS LATE WEDNESDAY NIGHT.
THERE WILL BE A BRIEF PERIOD OF ADVISORY LEVEL CONDITIONS AHEAD OF
THE FRONT WEDNESDAY AFTERNOON IN THE NORTHERN OUTER WATERS.
A STRONG LOW PRESSURE SYSTEM IN THE BERING SEA WILL STEER A SERIES
OF FRONTS INTO THE COASTAL WATERS THURSDAY THROUGH SATURDAY. THE
NEXT CHANCE FOR ADVISORY LEVEL...OR HIGHER... CONDITIONS AFTER
WEDNESDAY WILL BE THURSDAY AFTERNOON...WITH MULTIPLE MODERATE
SWELL TRAINS COMBINING WITH MODERATE WIND WAVES. WEST SWELL WILL
BUILD TO AROUND 14 FEET AT 17 SECONDS FRIDAY MORNING. -MSC/SPILDE
&&
.PREV DISCUSSION... /ISSUED 600 PM PST TUE FEB 9 2016/
DISCUSSION...THE LATEST VISIBLE IMAGE SHOWS HIGH CLOUDS MOVING IN
FROM THE SOUTHWEST AND ARE THICKER IN THE SOUTHWEST PART OF THE
FORECAST AREA. HIGH AND SOME MID LEVEL CLOUDS WILL REMAIN TONIGHT,
BUT PROBABLY NOT ENOUGH TO KEEP LOW CLOUDS AND PATCHY FOG FROM
FORMING IN THE SAME AREAS AS THE PAST FEW NIGHTS.
THE UPPER RIDGE WILL GRADUALLY WEAKEN WITH THE RIDGE AXIS SHIFTING
EAST OVER THE NEXT FEW DAYS. THIS WILL OPEN UP THE DOOR FOR MORE
CLOUDS TO MOVE INTO THE AREA. ALSO A COUPLE OF WEAK FRONTS WILL MOVE
INTO THE AREA. THE FIRST FRONT IS EXPECTED TO ARRIVE WEDNESDAY
MORNING. I SUSPECT THE THE MODELS, IN PARTICULAR THE NAM ARE TOO
BULLISH WITH THE QPF FIELDS ALONG THE COAST AND MAY ONLY BE THE
SACRIFICIAL LAMB. TYPICALLY WHEN FRONTS LIKE THIS RUN INTO A RIDGE
(ESPECIALLY ONE THAT IS RATHER STRONG FOR THIS TIME OF THE YEAR)
THEY TEND TO WEAKEN AND DISSIPATE, HENCE THE REASONING FOR KEEPING
POPS BELOW GUIDANCE. HOWEVER, THE OMEGA FIELDS ARE HIGHER AT THE
COAST EARLY WEDNESDAY MORNING WHICH WOULD BE AN ARGUMENT FOR HIGHER
POPS. IT WILL BE INTERESTING WHAT THE HRRR SHOWS LATER THIS EVENING
AND TONIGHT (CURRENT RUN ONLY GOES OUT TO 3AM PST). THE EVENING AND
NIGHT SHIFT MAY NEED TO REEVALUATE THIS AND INCREASE POPS ALONG THE
COAST FOR WEDNESDAY MORNING IF THERE`S STRONGER EVIDENCE TO SUPPORT
IT.
SHOWERS (IF WE GET ANY) ON WEDNESDAY MORNING SHOULD BE CONFINED TO
THE COAST. THE REST OF THE AREA WILL BE DRY WITH MORE CLOUD COVER
AND COOLER TEMPERATURES, BUT STILL ABOVE NORMAL FOR THIS TIME OF THE
YEAR. THE PATTERN DOES NOT CHANGE MUCH ON THURSDAY. HOWEVER A WARM
FRONT WILL LIFT NORTH JUST OFF THE OREGON COAST. THE MODELS KEEP
MOST OF THE PRECIP OFFSHORE IN THE MORNING, THEN SHOWS SOME INLAND
DURING THE AFTERNOON. SUSPECT THIS ALSO MAY BE OVERDONE. INSTABILITY
IS MARGINAL AT BEST AND THE TRIGGER IS WEAK OR NON- EXISTENT.
THEREFORE, CONFIDENCE IS LOW THAT WE`LL GET ANYTHING. SO WE`LL
KEEP THINGS DRY FOR NOW BUT AS PREVIOUSLY MENTIONED, LATER SHIFTS
WILL WANT TO REEVALUATE.
THE RIDGE SHIFTS EAST AND WEAKENS FRIDAY AS THE UPPER TROUGH PUSHES
EAST INTO THE AREA BRINGING THE BEST CHANCE FOR MEASURABLE RAIN.
SNOW LEVELS WILL LOWER ON FRIDAY, BUT WILL REMAIN ABOVE ALL THE
PASSES. -PETRUCELLI
LONG TERM (SATURDAY THROUGH TUESDAY)...A MORE WESTERLY JET STREAM
WILL BRING A WARM FRONT INLAND ON SATURDAY. SNOW LEVELS ON SATURDAY
WILL RANGE FROM AROUND 5500 FEET IN OREGON AND UP TO 7000 FEET IN
THE MOUNT SHASTA AREA. BOTH THE GFS AND THE ECMWF ARE IN A FAIRLY
GOOD AGREEMENT SO CONFIDENCE IS HIGH ON OUR FORECAST AREA SEEING
MEASURABLE PRECIPITATION.
BY MONDAY HOWEVER BOTH MODELS STRENGTHENS THE RIDGE OVER THE WEST
COAST IN RESPONSE TO AN UPSTREAM TROUGH IN THE GULF OF ALASKA
ALTHOUGH THE RIDGE ON ECMWF IS NOT AS STRONG AND ALLOWS SOME
OVERRUNNING. AS A RESULT WE ARE KEEPING MONDAY DRY BUT RE-INTRODUCE
CHANCE POPS FOR COOS AND DOUGLAS COUNTIES ON TUESDAY. BOTH MODELS
INDICATE WE MAY SHIFT BACK TO A WET PATTER AROUND THE MIDDLE OF NEXT
WEEK. /FB
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS FROM 10 AM TO
4 PM PST WEDNESDAY FOR PZZ370.
$$
MAS/MAP/MSC
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
617 PM EST THU FEB 11 2016
.SYNOPSIS...
AN ARCTIC COLD FRONT WILL DELIVER THE COLDEST AIR OF THE SEASON
FOR VALENTINES WEEKEND. THE ARCTIC FRONTAL BOUNDARY WILL BE
ACCOMPANIED BY A ROUND OF BLINDING SNOW SQUALLS LATE FRIDAY AND
FRIDAY NIGHT...FOLLOWED BY DANGEROUS COLD AND VERY LOW WIND CHILLS
THAT ARE EXPECTED TO IMPACT THE AREA SATURDAY INTO SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
NUMEROUS...NARROW BANDS OF SNOW SHOWERS AND BRIEF SQUALLS
CONTINUE TO STREAM SE AND WELL INLAND FROM THE GLAKES...WITH THE
LATEST RADAR TRENDS STARTING TO HINT AT A LITTLE WEAKENING.
LATEST HRRR REALLY DRIES THINGS UP FAST OVER THE NEXT FEW HOURS.
BUFKIT INDICATES INVERSION HEIGHTS DROPPING FAST SO THIS SOLUTION
LOOKS REASONABLE.
WILL MAINTAIN CURRENT WINTER WEATHER HEADLINES WHICH WRAP UP AT
03Z/10 PM. UNLESS THINGS WIND DOWN EVEN MORE RAPIDLY THAN EXPECTED...WE
WILL LET THINGS RUN UNTIL THE CURRENT EXPIRATION TIMES.
THE WIND WILL MAKE IT FEEL MUCH COLDER WITH WIND CHILLS BETWEEN
-10 AND +10 ACROSS THE ENTIRE AREA. THE BLUSTERY CONDITIONS WILL
JUST BE A TASTE OF WHAT IT IS ON THE HORIZON FOR LATER FRIDAY
NIGHT RIGHT INTO SUNDAY.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
SFC HIGH PRESSURE WILL SLIDE SOUTH OF THE STATE LATE TONIGHT
BRINGING GRADUAL CLEARING. FLURRIES AND SCATTERED SNOW SHOWERS
WILL LIFT NORTH EARLY TONIGHT AND BE CONFINED MAINLY TO THE
NORTHERN TIER BY AROUND MIDNIGHT.
TEMPS DROP INTO THE SINGLE DIGITS TONIGHT AS SOME CLEARING TAKES
PLACE IN THE NW...BUT THE CALM AIR IN THE SE COULD CAUSE THE TEMPS
THERE TO BECOME COLDER IN A FEW OF THE PERENNIAL COLD RURAL
AREAS...SUCH AS SEG AND THV - MAKING THEM 3-5F COLDER THAN THE
SURROUNDING LOCALES.
THE FIRST PART OF FRIDAY SHOULD BE QUIET WITH PARTLY TO MOSTLY
SUNNY SKIES AND RELATIVELY LIGHT WSW WIND. CLOUDS WILL QUICKLY
INCREASE FROM THE SW AS SOME MEAGER WARM ADVECTION KICKS IN AHEAD
OF THE WELL- ADVERTISED ARCTIC FRONT. SOME LIGHT SNOW/SNOW
SHOWERS WILL DEVELOP DURING THE AFTN...BUT ACCUMS SHOULD BE MEAGER
/GENERALLY UNDER 1/2 INCH. TEMPS WILL TRY TO GET INTO THE 20S ALL
OVER BUT THE PERSISTENT CLOUD COVER IN THE NW WILL LIKELY LIMIT
THEM TO THE UPPER TEENS.
ARCTIC FRONT AND AN EXPANSIVE AREA OF STEEP 850-700 MB LAPSE
RATES GREATER THAN 8C/KM WILL PLOW ACROSS THE STATE LATE
FRIDAY IN THE NW...AND AFTER DARK - FRIDAY NIGHT ELSEWHERE. THIS
SHOULD BE ONE OF THOSE ONCE IN A YEAR /OR SEVERAL YEAR/ EVENTS
COMPLETE WITH DANGEROUS BLINDING SNOW SQUALLS CREATING WIDESPREAD
TRAFFIC/TRAVEL PROBLEMS...FROM THE COMBINED EFFECT OF HEAVY
FALLING AND BLOWING SNOW - AMOUNTING TO BETWEEN 1-3 INCHES IN A
SHORT 30 TO 60 MINUTE PERIOD. THUNDER WAS ALSO MENTIONED IN THE
GRIDDED WEATHER FIELDS...ESP ACROSS THE NW HALF OF THE STATE BASED
ON THE LATE DAY/EVENING TIMING OF THE ARCTIC FROPA.
WIND CHILLS DIP TO UNDER ADVISORY CRITERIA /-15F/ EARLY SAT
MORNING ACROSS THE NRN MTNS...AND DROP TO NEAR OR SEVERAL DEG F
BELOW ZERO ELSEWHERE BY THEN.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
*IMPACT WEATHER HIGHLIGHTS: FRIGID TEMPERATURES AND DANGEROUS WIND
CHILLS FOR VALENTINES WEEKEND. POTENTIAL WINTER STORM EARLY NEXT
WEEK.
POLAR VORTEX DIVING INTO NORTHERN NEW ENGLAND WILL DELIVER THE
COLDEST AIR OF THE SEASON WITH ARCTIC BLAST INTO CENTRAL PA SAT-
SUN. THE GLOBAL MODELS AND ENSEMBLES KEEP A MEAN TROUGH IN PLACE
OVER THE EASTERN US INTO THE MIDDLE OF NEXT WEEK. THE MOST NOTABLE
FEATURE DURING THE PERIOD WILL BE A LOW PRESSURE SYSTEM TRACKING
UP THE EAST COAST ON TUESDAY. THE LATEST 11/12Z MODEL GUIDANCE
HAS TRENDED WEST WITH THE LOW TRACK...BUT THERE IS STILL A DECENT
SPREAD. AT THIS TIME PRECIPITATION WITH THIS SYSTEM APPEARS LIKELY
MON-TUE BUT THE TRACK WILL ULTIMATELY DETERMINE PRECIPITATION
TYPE. NEXT WEEK SHOULD END ON A MILDER NOTE.
THE COLDEST AIRMASS OF THE 2015-16 WINTER SEASON REMAINS POISED
TO ARRIVE THIS WEEKEND...AS A BLAST OF ARCTIC AIR DELIVERS A SHORT
DURATION COLD OUTBREAK TO CENTRAL PENNSYLVANIA. SNOW SQUALLS ARE
LIKELY WITH THE ARCTIC FRONTAL PASSAGE FRIDAY NIGHT INTO SATURDAY.
MAX/MIN TEMPERATURE DEPARTURES OF -20 TO -25 DEGREES BELOW CLIMO
ARE FCST SATURDAY AND SUNDAY. MINIMUM TEMPERATURES SATURDAY NIGHT
INTO EARLY SUNDAY MORNING RANGE FROM 0F IN THE LOWER SUSQ. VALLEY
TO -10F IN THE NORTHWEST ALLEGHENIES. THE FRIGID TEMPERATURES
COMBINED WITH DANGEROUS WIND CHILLS /-10 TO -25 BELOW ZERO/ WILL
RESULT IN AN INCREASED RISK FOR FROSTBITE AND HYPOTHERMIA. A WIND
CHILL WATCH WAS ISSUED FOR NORTHERN PA WHERE CONFIDENCE IS HIGH IN
REACHING -25F WIND CHILLS. WIND CHILL HEADLINES ARE A GOOD BET
IN LATER SHIFTS FOR THE REMAINDER OF THE AREA AND PRECAUTIONS
SHOULD BE MADE NOW TO PROTECT/PREPARE FOR THE UPCOMING COLD SNAP.
A MODERATION (WARMING TREND) IS EXPECTED INTO EARLY NEXT WEEK.
THE MODEL SPREAD HAS NARROWED A BIT CONCERNING A POTENTIAL WINTER
STORM SYSTEM IMPACTING THE MID ATLC/NORTHEAST NEXT MON-TUE. THE
11/12Z OPERATIONAL EC REMAINS ON THE WWD EDGE OF THE ENVELOPE
FOLLOWED BY THE CANADIAN GEM AND GFS/GEFS. THE GFS/GEFS HAVE BOTH
TRENDED WWD FROM THE PREVIOUS RUN. CONFIDENCE REMAINS LOW ON
PTYPES BUT ALL THE MODELS ARE SIGNALING A SIGNIFICANT QPF
EVENT...AND THEREFORE HAVE INCREASED POPS IN THE THE LKLY RANGE
FOR DAY 5.5-6 /MON NGT-TUESDAY/.
&&
.AVIATION /23Z THURSDAY THROUGH TUESDAY/...
LAKE ENHANCED OROGRAPHIC SNOW WILL RESULT IN MAINLY IFR VSBYS AT
KBFD/KJST AND POSSIBLY MVFR AT AOO...THROUGH THE FIRST HALF OF THE
EVENING. THESE CONDITIONS WILL GRADUALLY IMPROVE WHEN THE MEAN
LLVL WIND BACKS FROM THE NW...TO A MORE WESTERLY DIRECTION AS HIGH
PRESSURE SLIDES BY JUST TO OUR SOUTH ACROSS THE MIDDLE OHIO RIVER
VALLEY...BY 06Z.
THROUGHOUT THE CENTRAL RIDGE...THE VALLEY REGION...AND OVER THE
SUSQ VALLEY AIRFIELDS...EXPECT MAINLY VFR CONDITIONS. THE SNOW
BANDS COULD POSSIBLY BRING IPT AT UNV TO MFR CIGS THROUGH 03Z...WITH
EVEN SOME VERY BRIEF IFR IN THE HEAVIER SNOW SHOWERS AND SQUALLS.
A TIGHT PRES GRADIENT WILL BRING GUSTY WINDS UP TO 35KTS FOR THE
REST OF THIS AFTERNOON AND EARLY EVENING AS DIURNAL
HEATING/MIXING WITHIN THE RATHER DEEP BOUNDARY LAYER ALLOWS
STRONGER WINDS ALOFT TO MIX TO GROUND LEVEL.
ARRIVAL OF SFC RIDGE SHOULD BRING WIDESPREAD VFR CONDS AND
DIMINISHING WIND TO CENTRAL PA THIS EVENING...AND CONTINUING
THROUGH AT LEAST THE FIRST HALF OF FRIDAY.
OUTLOOK...
FRI...PM SHSN/VIS REDUCTIONS LIKELY...ESP W MTNS. PERIODS OF
LIFR/VLIFR IN INTENSE SNOW SQUALLS LATE FRIDAY /NW/ AND FRIDAY
NIGHT EARLY SAT MORNING CENTRAL AND SE.
SAT...WINDY. SHSN/REDUCED VIS POSS W MTNS...MAINLY AM.
SUN...NO SIG WX EXPECTED.
MON...PM SNOW POSSIBLE.
MON NIGHT AND TUE...SNOW LIKELY NW HALF OF PENN...WITH RAIN OR
SNOW IN THE SE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ005.
WIND CHILL WATCH FROM LATE FRIDAY NIGHT THROUGH SUNDAY MORNING
FOR PAZ004>006-037-041-042.
LAKE EFFECT SNOW WARNING UNTIL 10 PM EST THIS EVENING FOR
PAZ004.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ010-017-024-033.
&&
$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...STEINBUGL
AVIATION...LAMBERT/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
408 PM EST WED FEB 10 2016
.SYNOPSIS...
A FEW COMPACT DISTURBANCES WILL SLIDE SOUTHEAST OVER THE NEXT
SEVERAL DAYS THROUGH A DEEP UPPER TROUGH OVER THE NORTHEASTERN
U.S.. A PERSISTENT NORTHWEST FLOW WILL BRING A PROLONGED PERIOD
OF LAKE EFFECT AND UPSLOPE SNOW SHOWERS THROUGHOUT THE NORTHWEST
SNOWBELT AND ACROSS THE LAUREL HIGHLANDS. AN ARCTIC BLAST WILL
DELIVER THE COLDEST AIR OF THE SEASON FOR VALENTINES WEEKEND WITH
DANGEROUS COLD AND WIND CHILLS EXPECTED TO IMPACT THE AREA
SATURDAY INTO SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
MOSTLY CLOUDY SKIES AND BLUSTERY CONDITIONS WITH FLURRIES AND A
FEW BRIEF SNOW SHOWERS WILL BE FOUND ACROSS MUCH OF THE CENTRAL
RIDGE AND VALLEY REGION LATE THIS AFTERNOON INTO THIS EVENING
WITH WEAK LLVL RIDGING IN PLACE.
PERSISTENT UPSLOPE SNOW SHOWERS AND FREQUENT LES FROM MEANDERING
SNOW BANDS ACROSS THE FAR NW ZONES WILL BRING AN ADDITIONAL 1 TO 2
INCHES EVERY 4 TO 6 HOURS THROUGH TONIGHT...THOUGH PORTIONS OF NW
WARREN COUNTY COULD SEE NEARLY DOUBLE THOSE SNOWFALL RATES.
18Z HRRR HAS BEEN FAIRLY CONSISTENT WITH ITS PAST SEVERAL RUNS IN
DISPLAYING SIMILAR TIMING OF A NARROW NE-SW ORIENTED BAND OF
BRIEFLY HEAVY SNOW SHOWERS AND POSSIBLE SQUALLS...THAT WILL
ACCOMPANY A SECONDARY CFRONT ACROSS THE NW MTNS LATE TODAY BEFORE
REACHING A KELM TO KFIG LINE AROUND 00Z THURSDAY.
ONCE THIS SNOW BAND SLIDES OFF THE HIGHER TERRAIN OF THE
ALLEGHENY PLATEAU LATER THIS EVENING...AND LLVL INSTABILITY WANES
A BIT...THE HRRR IS PROBABLY ON TRACK WITH WEAKENING IT BY 02Z
NEAR A KAVP...TO KSEG AND KUNV LINE.
THE WELL-ALIGNED SFC-800 MB FLOW FROM ABOUT 270 DEGREES...WILL
VEER TO ABOUT 295 DEG LATE TODAY/EARLY TONIGHT AS THE
AFOREMENTIONED SECONDARY COLD FRONT SWINGS SE THROUGH THE AREA.
THE FRONT COULD BRING A QUICK 1/2 INCH ALONG AND EAST OF THE
INTERSTATE 99/RT 22 CORRIDOR...WITH UP TO ONE INCH ON THE HIGH
TERRAIN TO THE NORTH AND WEST.
BASED ON THE MODERATELY STRONG...WELL ALIGNED...AND PERSISTENT 280-290
DEG FLOW LATE TODAY THROUGH ABOUT 04Z FRIDAY...WE EXTENDED THE
WINTER WX AND LES ADVISORIES AND WARNINGS OUT IN TIME THROUGH 03Z
FRIDAY...AND EXPANDED THE WINT WX ADVIS NORTH TO COVER ELK AND
CLEARFIELD COUNTIES.
LATER TONIGHT...LOOK FOR VARIABLE AMOUNTS OF CLOUDS WITH SCATTERED
FLURRIES ACROSS THE SUSQ VALLEY AND SOUTHERN TIER...WHILE A FEW
BRIEF SNOW SHOWERS IN NARROW NW-SE STREAMERS OFF LAKE ERIE COULD
ADD AN ADDITIONAL LIGHT COATING FROM KAOO TO KUNV.
TEMPS ARE RIGHT AROUND THEIR FCST MAXES OF AROUND 20F ACROSS THE
LAUREL HIGHLANDS...AND IN THE U20S TO LOWER 30S HEADING FROM THE
CENTRAL MTNS TO THE MIDDLE AND LOWER SUSQ VALLEY.
LOWS TONIGHT WILL VARY FROM 5-10F ACROSS THE NORTHERN AND WESTERN
MTNS...TO THE UPPER TEENS IN THE SUSQ VALLEY. WIND CHILLS COULD
DIP TO NEAR -10F AT TIMES LATE TONIGHT ACROSS THE NRN AND WRN
MTNS...AND IN THE ZERO TO 10 ABOVE RANGE ACROSS THE CENTRAL AND SE
ZONES...BUT WILL BE A GOOD 5 TO 10 DEG F ABOVE WIND CHILL ADVISORY
CRITERIA IN ANY OF THESE LOCATIONS.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
PERSISTENT...MEAN BLYR FLOW FROM 280-290 DEGREES WILL LEAD TO
WIDESPREAD STRATO CU WITH CLOUD TEMPS ACROSS MUCH OF CENTRAL PENN
FALLING WITHIN THE FAVORABLE DGZ OF -12 TO -18C.
THIS WILL LEAD TO WIDESPREAD FLURRIES AND BRIEF SNOW SHOWERS FROM
NARROW...AND SLOWLY MEANDERING BANDS. MESOSCALE MODELS SUCH AS
THE HRRR AND 3 KM NCAR ENSEMBLE WILL PLAY AN IMPORTANT ROLE IN
FORECASTING THE LOCATION...MVMT...AND SNOW FROM THESE FAIRLY WELL-
ORGANIZED BUT NARROW SNOW BANDS THAT WILL REACH INTO THE CENTRAL
RIDGE AND VALLEY REGION AT TIMES.
ADDITIONAL SNOW ACCUMS OF A FEW TO SEVERAL INCHES WILL OCCUR
DURING THE DAYLIGHT HOURS THURSDAY ACROSS THE NW MTNS AND LAUREL
HIGHLANDS WHERE THE WINT WX AND LES ADVISORIES...AND LES WARNINGS
WILL CONTINUE.
MAX TEMPS THURSDAY WILL BE ONLY 12-25F WHICH IS AROUND 15 DEG F
BELOW NORMAL FOR THIS TIME OF YEAR.
THE BULK OF THE MORE SIGNIFICANT SNOW SHOWERS/LES SHOULD TAPER
OFF/LIFT TO THE NORTH...CLOSELY HUGGING THE I-90 CORRIDOR AS MEAN
BLYR WINDS BACK MORE TO THE WSW AFTER MIDNIGHT.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
*IMPACT WEATHER HIGHLIGHTS: SNOW SQUALLS LIKELY WITH ARCTIC FRONT
FRIDAY NIGHT-SATURDAY. FRIGID TEMPERATURES AND DANGEROUS WIND
CHILLS FOR VALENTINES WEEKEND.
POLAR VORTEX DIVES FROM HUDSON BAY SOUTHEAST ACROSS QUEBEC AND
NORTHERN NEW ENGLAND THURSDAY-SUNDAY. THE GLOBAL MODELS AND
ENSEMBLE MEANS KEEP A `MILDER` TROUGH PATTERN IN PLACE OVER THE
EASTERN US INTO NEXT WEEK. EMERGENCE OF SOUTHERN STREAM SHORTWAVE
AND ITS INTERACTION WITH THE NORTHERN STREAM FLOW CREATES THE
POTENTIAL FOR WINTER PRECIPITATION MON-WED BUT WITH A HIGH DEGREE
OF UNCERTAINTY/LOW CONFIDENCE. A PATTERN SHIFT TO PACIFIC ZONAL-TO
SOUTHWEST FLOW ALOFT WITH RISING/ABOVE NORMAL HEIGHTS IS FCST BY
THE END OF NEXT WEEK. THIS FAVORS A RETURN TO MILDER WEATHER.
LAKE EFFECT AND UPSLOPE SNOW SHOWERS CONTINUE INTO THE WEEKEND
BEFORE TAPERING OFF ON SUNDAY...AS ARCTIC HIGH BUILDS OVER THE
REGION. ADDITIONAL LIGHT SNOW ACCUMULATIONS ARE LIKELY IN THE
FAVORED NORTHWEST SNOWBELT AND HIGHER TERRAIN ALONG THE
ALLEGHENIES/LAUREL HIGHLANDS.
THE COLDEST AIRMASS OF THE 2015-16 WINTER SEASON REMAINS POISED
TO ARRIVE THIS WEEKEND...AS A BLAST OF ARCTIC AIR DELIVERS A SHORT
DURATION COLD OUTBREAK TO CENTRAL PENNSYLVANIA. SNOW SQUALLS ARE
LIKELY WITH THE ARCTIC FRONTAL PASSAGE FRIDAY NIGHT INTO SATURDAY.
MAX/MIN TEMPERATURE DEPARTURES OF -20 TO -25 DEGREES BELOW CLIMO
ARE FCST SATURDAY AND SUNDAY. MINIMUM TEMPERATURES SATURDAY NIGHT
INTO EARLY SUNDAY MORNING RANGE FROM 0F IN THE LOWER SUSQ. VALLEY
TO -10F IN THE NORTHWEST ALLEGHENIES. THE FRIGID TEMPERATURES
COMBINED WITH DANGEROUS WIND CHILLS /-10 TO -25 BELOW ZERO/ WILL
RESULT IN AN INCREASED RISK FOR FROSTBITE AND HYPOTHERMIA. WIND
CHILL HEADLINES ARE A GOOD BET AND PRECAUTIONS SHOULD BE MADE NOW
TO PROTECT/PREPARE FOR THE UPCOMING COLD SNAP.
A MODERATION (WARMING TREND) IS EXPECTED INTO EARLY NEXT WEEK.
THERE IS STILL A LOT OF SPREAD CONCERNING A POTENTIAL STORM SYSTEM
IMPACTING THE NORTHEAST EARLY NEXT WEEK. THE OPERATIONAL EC
REMAINS MORE BULLISH THAN THE GFS IN DEVELOPING A SIGNIFICANT
CYCLONE AND HAS TRENDED EVEN FURTHER TO THE WEST WITH IS 10/12Z
RUN. CONFIDENCE REMAINS LOW BUT THE SYSTEM WILL NEED TO BE MONITORED.
&&
.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
MAINLY VFR CIGS AND VSBYS WILL PREVAIL ACROSS THE SUSQ VALLEY TAF
SITES /KIPT...KMDT AND KLNS/ WITH HIGH END MVFR CIGS AND VFR TO
MVFR VSBYS AT KUNV AND KAOO.
THE POOREST FLYING CONDITIONS WILL CONTINUE TO BE AT KJST AND
KBFD FOR THE NEXT SEVERAL DAYS...WHERE CIGS AND VSBYS WILL BE
MAINLY IN THE MVFR TO UPPER IFR RANGE...WITH OCNL DIPS TO
LIFR/VLIFR IN LAKE EFFECT SNOW BANDS AND AREAS OF ENHANCED UPSLOPE
SNOWS.
FOR KUNV...KAOO...AND PERHAPS KIPT...EXPECT UP TO A FEW HOUR
PERIOD OF MORE FREQUENT SNOW SHOWERS LATE TODAY AND AFTER
SUNSET...AS A SECONDARY COLD FRONT PUSHES THROUGH THE AREA.
GUSTY WEST TO WNW WINDS WILL PREVAIL THIS AFTERNOON...TONIGHT AND
AND THURSDAY...AVERAGING 12-15 KTS WITH GUSTS IN THE LOW-MID 20
KT RANGE.
OUTLOOK...
THU/THU NIGHT...MVFR WITH PERIODS OF IFR IN -SHSN ACROSS THE WRN
PENN MTNS. MAINLY VFR ELSEWHERE.
FRI...MVFR IN -SHSN...MAINLY LATE WITH STRONG COLD FRONT.
SAT...MVFR IN -SHSN W MTNS. VFR OTHERWISE. WINDY.
SUN...MVFR IN -SHSN IN W MTNS EARLY...OTHERWISE VFR.
MON...VFR POSSIBLE EARLY ACROSS THE EASTERN HALF OF PENN...THEN
LOWERING AND THICKENING CLOUDS LIKELY WITH A FEW PERIODS OF SNOW
POSSIBLE...YIELDING MVFR TO IFR VSBYS AND CIGS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 10 PM EST THURSDAY FOR PAZ005.
LAKE EFFECT SNOW WARNING UNTIL 10 PM EST THURSDAY FOR PAZ004.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THURSDAY FOR PAZ010-
017-024-033.
&&
$$
SYNOPSIS...LAMBERT/STEINBUGL
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...STEINBUGL
AVIATION...LAMBERT
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
252 PM EST WED FEB 10 2016
.SYNOPSIS...
A FEW COMPACT DISTURBANCES WILL SLIDE SOUTHEAST OVER THE NEXT
SEVERAL DAYS THROUGH A DEEP UPPER TROUGH OVER THE NORTHEASTERN
U.S.. A PERSISTENT NORTHWEST FLOW WILL BRING IN THE COLDEST AIR
OF THE SEASON...WHILE ALSO CREATING A PROLONGED PERIOD OF LAKE
EFFECT AND UPSLOPE SNOW SHOWERS THROUGHOUT THE NORTHWEST PENN
SNOW BELT...AND ACROSS THE LAUREL HIGHLANDS.
&&
.NEAR TERM /THROUGH TONIGHT/...
MOSTLY CLOUDY SKIES AND BLUSTERY CONDITIONS WITH FLURRIES AND A
FEW BRIEF SNOW SHOWERS WILL BE FOUND ACROSS MUCH OF THE CENTRAL
RIDGE AND VALLEY REGION LATE THIS AFTERNOON INTO THIS EVENING
WITH WEAK LLVL RIDGING IN PLACE.
PERSISTENT UPSLOPE SNOW SHOWERS AND FREQUENT LES FROM MEANDERING
SNOW BANDS ACROSS THE FAR NW ZONES WILL BRING AN ADDITIONAL 1 TO 2
INCHES EVERY 4 TO 6 HOURS THROUGH TONIGHT...THOUGH PORTIONS OF NW
WARREN COUNTY COULD SEE NEARLY DOUBLE THOSE SNOWFALL RATES.
18Z HRRR HAS BEEN FAIRLY CONSISTENT WITH ITS PAST SEVERAL RUNS IN
DISPLAYING SIMILAR TIMING OF A NARROW NE-SW ORIENTED BAND OF
BRIEFLY HEAVY SNOW SHOWERS AND POSSIBLE SQUALLS...THAT WILL
ACCOMPANY A SECONDARY CFRONT ACROSS THE NW MTNS LATE TODAY BEFORE
REACHING A KELM TO KFIG LINE AROUND 00Z THURSDAY.
ONCE THIS SNOW BAND SLIDES OFF THE HIGHER TERRAIN OF THE
ALLEGHENY PLATEAU LATER THIS EVENING...AND LLVL INSTABILITY WANES
A BIT...THE HRRR IS PROBABLY ON TRACK WITH WEAKENING IT BY 02Z
NEAR A KAVP...TO KSEG AND KUNV LINE.
THE WELL-ALIGNED SFC-800 MB FLOW FROM ABOUT 270 DEGREES...WILL
VEER TO ABOUT 295 DEG LATE TODAY/EARLY TONIGHT AS THE
AFOREMENTIONED SECONDARY COLD FRONT SWINGS SE THROUGH THE AREA.
THE FRONT COULD BRING A QUICK 1/2 INCH ALONG AND EAST OF THE
INTERSTATE 99/RT 22 CORRIDOR...WITH UP TO ONE INCH ON THE HIGH
TERRAIN TO THE NORTH AND WEST.
BASED ON THE MODERATELY STRONG...WELL ALIGNED...AND PERSISTENT 280-290
DEG FLOW LATE TODAY THROUGH ABOUT 04Z FRIDAY...WE EXTENDED THE
WINTER WX AND LES ADVISORIES AND WARNINGS OUT IN TIME THROUGH 03Z
FRIDAY...AND EXPANDED THE WINT WX ADVIS NORTH TO COVER ELK AND
CLEARFIELD COUNTIES.
LATER TONIGHT...LOOK FOR VARIABLE AMOUNTS OF CLOUDS WITH SCATTERED
FLURRIES ACROSS THE SUSQ VALLEY AND SOUTHERN TIER...WHILE A FEW
BRIEF SNOW SHOWERS IN NARROW NW-SE STREAMERS OFF LAKE ERIE COULD
ADD AN ADDITIONAL LIGHT COATING FROM KAOO TO KUNV.
TEMPS ARE RIGHT AROUND THEIR FCST MAXES OF AROUND 20F ACROSS THE
LAUREL HIGHLANDS...AND IN THE U20S TO LOWER 30S HEADING FROM THE
CENTRAL MTNS TO THE MIDDLE AND LOWER SUSQ VALLEY.
LOWS TONIGHT WILL VARY FROM 5-10F ACROSS THE NORTHERN AND WESTERN
MTNS...TO THE UPPER TEENS IN THE SUSQ VALLEY. WIND CHILLS COULD
DIP TO NEAR -10F AT TIMES LATE TONIGHT ACROSS THE NRN AND WRN
MTNS...AND IN THE ZERO TO 10 ABOVE RANGE ACROSS THE CENTRAL AND SE
ZONES...BUT WILL BE A GOOD 5 TO 10 DEG F ABOVE WIND CHILL ADVISORY
CRITERIA IN ANY OF THESE LOCATIONS.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
PERSISTENT...MEAN BYLR FLOW FROM 280-290 DEGREES WILL LEAD TO
WIDESPREAD STRATO CU WITH CLOUD TEMPS ACROSS MUCH OF CENTRAL PENN
FALLING WITHIN THE FAVORABLE DGZ OF -12 TO -18C.
THIS WILL LEAD TO WIDESPREAD FLURRIES AND BRIEF SNOW SHOWERS FROM
NARROW...AND SLOWLY MEANDERING BANDS. MESOSCALE MODELS SUCH AS
THE HRRR AND 3 KM NCAR EMSEMBLE WILL PLAY AN IMPORTANT ROLE IN
FORECASTING THE LOCATION...MVMT...AND SNOW FROM THESE FAIRLY WELL-
ORGANIZED BUT NARROW SNOW BANDS THAT WILL REACH INTO THE CENTRAL
RIDGE AND VALLEY REGION AT TIMES.
ADDITIONAL SNOW ACCUMS OF A FEW TO SEVERAL INCHES WILL OCCUR
DURING THE DAYLIGHT HOURS THURSDAY ACROSS THE NW MTNS AND LAUREL
HIGHLANDS WHERE THE WINT WX AND LES ADVISORIES...AND LES WARNINGS
WILL CONTINUE.
MAX TEMPS THURSDAY WILL BE ONLY 12-25F WHICH IS AROUND 15 DEG F
BELOW NORMAL FOR THIS TIME OF YEAR.
THE BULK OF THE MORE SIGNIFICANT SNOW SHOWERS/LES SHOULD TAPER
OFF/LIFT TO THE NORTH...CLOSELY HUGGING THE I-90 CORRIDOR AS MEAN
BLYR WINDS BACK MORE TO THE WSW AFTER MIDNIGHT.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
*IMPACT WEATHER HIGHLIGHTS: SNOW SQUALLS POSSIBLE WITH ARCTIC
FRONT FRIDAY NIGHT-EARLY SATURDAY. FRIGID TEMPERATURES/DANGEROUS
WIND CHILLS FOR VALENTINES WEEKEND.
POLAR VORTEX DIVES FROM HUDSON BAY SOUTHEAST ACROSS QUEBEC AND
NORTHERN NEW ENGLAND THURSDAY-SUNDAY. THE GLOBAL MODELS AND
ENSEMBLE MEANS KEEP A `MILDER` TROUGH PATTERN IN PLACE OVER THE
NORTHEAST CONUS INTO NEXT WEEK.
THE FIRST SHOT OF COLD AIR ARRIVES ON THURSDAY WITH LAKE EFFECT
AND UPSLOPE SNOW SHOWERS TAPERING OFF THURSDAY NIGHT. LIGHT TO
MODERATE SNOW ACCUMULATIONS ARE LIKELY IN THE FAVORED NORTHWEST
SNOWBELT AND HIGHER TERRAIN ALONG THE ALLEGHENIES/LAUREL
HIGHLANDS.
THE COLDEST AIRMASS OF THE 2015-16 WINTER SEASON REMAINS POISED
TO ARRIVE THIS WEEKEND...AS A BLAST OF ARCTIC AIR DELIVERS A SHORT
DURATION COLD OUTBREAK TO CENTRAL PENNSYLVANIA. SNOW SQUALLS ARE
POSSIBLE WITH THE ARCTIC FRONTAL PASSAGE FRIDAY NIGHT INTO EARLY
SATURDAY.
MAX/MIN TEMPERATURE DEPARTURES OF -20 TO -25 DEGREES BELOW CLIMO
ARE FCST SATURDAY AND SUNDAY. MINIMUM TEMPERATURES SATURDAY NIGHT
INTO EARLY SUNDAY MORNING RANGE FROM AROUND 0F IN THE LOWER SUSQ.
VALLEY TO -10F IN THE NORTHWEST ALLEGHENIES. THE FRIGID TEMPERATURES
COMBINED WITH DANGEROUS WIND CHILLS /-10 TO -25 BELOW ZERO/ WILL
RESULT IN AN INCREASED RISK FOR FROSTBITE AND HYPOTHERMIA.
A SLOW MODERATION (WARMING TREND) IS EXPECTED INTO EARLY NEXT
WEEK...BUT WITH A POTENTIAL OVERRUNNING/WAA TYPE SNOW EVENT.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
MAINLY VFR CIGS AND VSBYS WILL PREVAIL ACROSS THE SUSQ VALLEY TAF
SITES /KIPT...KMDT AND KLNS/ WITH HIGH END MVFR CIGS AND VFR TO
MVFR VSBYS AT KUNV AND KAOO.
THE POOREST FLYING CONDITIONS WILL CONTINUE TO BE AT KJST AND
KBFD FOR THE NEXT SEVERAL DAYS...WHERE CIGS AND VSBYS WILL BE
MAINLY IN THE MVFR TO UPPER IFR RANGE...WITH OCNL DIPS TO
LIFR/VLIFR IN LAKE EFFECT SNOW BANDS AND AREAS OF ENHANCED UPSLOPE
SNOWS.
FOR KUNV...KAOO...AND PERHAPS KIPT...EXPECT UP TO A FEW HOUR
PERIOD OF MORE FREQUENT SNOW SHOWERS LATE TODAY AND AFTER
SUNSET...AS A SECONDARY COLD FRONT PUSHES THROUGH THE AREA.
GUSTY WEST TO WNW WINDS WILL PREVAIL THIS AFTERNOON...TONIGHT AND
AND THURSDAY...AVERAGING 12-15 KTS WITH GUSTS IN THE LOW-MID 20
KT RANGE.
OUTLOOK...
THU/THU NIGHT...MVFR WITH PERIODS OF IFR IN -SHSN ACROSS THE WRN
PENN MTNS. MAINLY VFR ELSEWHERE.
FRI...MVFR IN -SHSN...MAINLY LATE WITH STRONG COLD FRONT.
SAT...MVFR IN -SHSN W MTNS. VFR OTHERWISE. WINDY.
SUN...MVFR IN -SHSN IN W MTNS EARLY...OTHERWISE VFR.
MON...VFR POSSIBLE EARLY ACROSS THE EASTERN HALF OF PENN...THEN
LOWERING AND THICKENING CLOUDS LIKELY WITH A FEW PERIODS OF SNOW
POSSIBLE...YIELDING MVFR TO IFR VSBYS AND CIGS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 10 PM EST THURSDAY FOR PAZ005.
LAKE EFFECT SNOW WARNING UNTIL 10 PM EST THURSDAY FOR PAZ004.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THURSDAY FOR PAZ010-
017-024-033.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...STEINBUGL
AVIATION...LAMBERT
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
636 AM EST WED FEB 10 2016
.SYNOPSIS...
A DEEP UPPER TROUGH WILL ESTABLISH ITSELF OVER THE NORTHEASTERN
U.S. OVER THE NEXT SEVERAL DAYS. A CONSTANT NORTHWEST FLOW WILL
BRING IN THE COLDEST AIR OF THE SEASON AS WELL AS CREATE A
PROLONGED PERIOD OF SNOW SHOWERS IN THE SNOW BELT AND LAUREL
HIGHLANDS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
630 AM UPDATE...
SNOW FINALLY DONE IN THE SE...AND GENERAL UPSLOPE WEAK
RETURNS/LIGHT SNOW OVER WRN PA AND SOME STREAMERS CROSSING THRU
KCLE AND HEADED FOR OUR WESTERN COS. WILL KEEP HIGHEST POPS IN
THE NW AND DURING THE AFTN. BFD AND JST ARE BOTH NEAR 1SM IN -SN
ATTM. NO CHANGES AS ALL IS CURRENTLY ON TRACK.
PREV...
LIGHT SNOW WINDING DOWN OVER YORK/LANCASTER COUNTIES. THE SNOW
OVER THE WEST IS STARTING TO FORM A COHERENT MASS BUT THIS MIGHT
NOT LAST LONG. THE VORT MAX CURRENTLY OVER KBUF WILL CONTINUE TO
SLIDE TO THE EAST AND POSSIBLY DIMINISH THE SNOW THIS MORNING
BEFORE IT PICKS BACK UP AGAIN LATE IN THE AFTERNOON. HRRR AND RAP
BOTH GENERATE AN E-W BAND OF SNOW ALONG AND JUST TO THE S OF RTE
6 THIS MORNING BUT IT BECOMES MIGRATORY THRU THE DAY. ONLY THE
LOWER SUSQ WILL HAVE A DECENT SHOT AT CLEARING OUT TODAY ON THE
DOWNHILL SIDE OF THE WESTERLY FLOW. OTHERWISE...MOSTLY CLOUDY AND
BLUSTERY IS BEST WORDING TODAY. GUSTS COULD BE INTO THE 20S AREA
WIDE AND NEAR 30MPH IN THE LAURELS. THIS COMBINE WITH THE SNOW
THERE COULD LEAD TO VERY POOR DRIVING. BUT THE SNOW INTENSITY WILL
NOT BE TOO TERRIBLE UNTIL LATER TODAY. ABOUT 4-5F IS ALL WE WILL
BE ABLE TO ADD TO MAXES TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
SHORT WAVE TROUGH SWINGS THRU THIS EVENING AND CARVES THE BASE OF
THE BIGGER TROUGH. THIS MAY LEAD TO A BRIEF PERIOD OF BETTER
ORGANIZATION TO THE UPSLOPE SNOW AND PUSH SOME ACCUMULATION OVER
THE ALLEGHENY FRONT INTO THE CENTRAL/RIDGE AND VALLEY REGION.
BUT ACCUMS IN THAT AREA WOULD BE ONLY AN INCH OR SO. IT GETS
UNIFORMLY COLDER ALL UP/DOWN THE COLUMN TONIGHT AND THE SATURATED
DGZ IS PIERCED THRU BY THE BEST UPWARD FORCING/OMEGAS. THUS...IT
SHOULD BE PRETTY EASY TO GET A FLUFFY SNOW OUT OF THE ATMOS
TONIGHT. SLR/S COULD BE 25:1 OR 30:1. SO EVEN WITHOUT SIGNIFICANT
QPF IN THE MDLS...WE SHOULD BE ON THE LOOKOUT FOR HIGHER THAN
CURRENTLY EXPECTED TOTALS. LOWS WILL DIP INTO THE SINGLE DIGITS IN
THE N/W AND WIND CHILLS GO INTO THE SINGLE DIGITS BELOW ZERO
OVERNIGHT/THURS MORNING.
AS THE TROUGH AXIS SLIDES TO THE EAST ON THURS...WE SHOULD IMPROVE
WITH SNOW SHOWERS TAPERING OFF IN THE MORNING IN THE LAURELS. BUT
IT COULD TAKE ALL DAY FOR THEM TO LIFT OUT OF THE SNOW BELT. HAVE
EXTENDED THE TIME OF THE WINT WX ADVY FOR THE LAURELS INTO THE
MIDDLE OF THE DAY THURS TO MATCH TIMES WITH OUR LK EFF ADVY. MAXES
WILL BE ONLY 12-25F WHICH ARE ABOUT 15 TO 25 DEGS BELOW NORMAL FOR
THIS TIME OF YEAR.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
*IMPACT WEATHER HIGHLIGHTS: SNOW SQUALLS POSSIBLE WITH ARCTIC
FRONT FRIDAY NIGHT-EARLY SATURDAY. FRIGID TEMPERATURES/DANGEROUS
WIND CHILLS FOR VALENTINES WEEKEND.
POLAR VORTEX DIVES FROM HUDSON BAY SOUTHEAST ACROSS QUEBEC AND
NORTHERN NEW ENGLAND THURSDAY-SUNDAY. THE GLOBAL MODELS AND
ENSEMBLE MEANS KEEP A `MILDER` TROUGH PATTERN IN PLACE OVER THE
NORTHEAST CONUS INTO NEXT WEEK.
THE FIRST SHOT OF COLD AIR ARRIVES ON THURSDAY WITH LAKE EFFECT
AND UPSLOPE SNOW SHOWERS TAPERING OFF THURSDAY NIGHT. LIGHT TO
MODERATE SNOW ACCUMULATIONS ARE LIKELY IN THE FAVORED NORTHWEST
SNOWBELT AND HIGHER TERRAIN ALONG THE ALLEGHENIES/LAUREL
HIGHLANDS.
THE COLDEST AIRMASS OF THE 2015-16 WINTER SEASON REMAINS POISED
TO ARRIVE THIS WEEKEND...AS A BLAST OF ARCTIC AIR DELIVERS A SHORT
DURATION COLD OUTBREAK TO CENTRAL PENNSYLVANIA. SNOW SQUALLS ARE
POSSIBLE WITH THE ARCTIC FRONTAL PASSAGE FRIDAY NIGHT INTO EARLY
SATURDAY.
MAX/MIN TEMPERATURE DEPARTURES OF -20 TO -25 DEGREES BELOW CLIMO
ARE FCST SATURDAY AND SUNDAY. MINIMUM TEMPERATURES SATURDAY NIGHT
INTO EARLY SUNDAY MORNING RANGE FROM AROUND 0F IN THE LOWER SUSQ.
VALLEY TO -10F IN THE NORTHWEST ALLEGHENIES. THE FRIGID TEMPERATURES
COMBINED WITH DANGEROUS WIND CHILLS /-10 TO -25 BELOW ZERO/ WILL
RESULT IN AN INCREASED RISK FOR FROSTBITE AND HYPOTHERMIA.
A SLOW MODERATION (WARMING TREND) IS EXPECTED INTO EARLY NEXT
WEEK...BUT WITH A POTENTIAL OVERRUNNING/WAA TYPE SNOW EVENT.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
12Z TAFS SENT.
EXPECT MOST OF THE AREA TO HAVE VFR CONDITIONS SHORTLY.
BULK OF THE SNOW NOW EAST OF THE AREA.
HOWEVER...BFD AND JST WILL LIKELY HAVE MVFR AND IFR
CONDITIONS WITH SNOW SHOWERS INTO THU.
GUSTY WINDS WILL PREVAIL TODAY AND THU.
FOR UNV...AND AOO...EXPECT SNOW SHOWERS TO MAKE IT BACK
INTO THE AREA AT TIMES TODAY AND AFTER SUNSET...AS COLDER
AIR WORKS INTO THE AREA.
OUTLOOK...
THU...MVFR IN -SHSN W MTNS. VFR ELSEWHERE.
FRI...MVFR IN -SHSN...MAINLY LATE WITH STRONG COLD FRONT.
SAT...MVFR IN -SHSN W MTNS. VFR OTHERWISE. WINDY.
SUN...MVFR IN -SHSN IN W MTNS EARLY...OTHERWISE VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THURSDAY FOR PAZ005.
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST THURSDAY FOR PAZ004.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THURSDAY FOR PAZ024-033.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...STEINBUGL
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
629 AM EST WED FEB 10 2016
.SYNOPSIS...
A DEEP UPPER TROUGH WILL ESTABLISH ITSELF OVER THE NORTHEASTERN
U.S. OVER THE NEXT SEVERAL DAYS. A CONSTANT NORTHWEST FLOW WILL
BRING IN THE COLDEST AIR OF THE SEASON AS WELL AS CREATE A
PROLONGED PERIOD OF SNOW SHOWERS IN THE SNOW BELT AND LAUREL
HIGHLANDS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LIGHT SNOW WINDING DOWN OVER YORK/LANCASTER COUNTIES. THE SNOW
OVER THE WEST IS STARTING TO FORM A COHERENT MASS BUT THIS MIGHT
NOT LAST LONG. THE VORT MAX CURRENTLY OVER KBUF WILL CONTINUE TO
SLIDE TO THE EAST AND POSSIBLY DIMINISH THE SNOW THIS MORNING
BEFORE IT PICKS BACK UP AGAIN LATE IN THE AFTERNOON. HRRR AND RAP
BOTH GENERATE AN E-W BAND OF SNOW ALONG AND JUST TO THE S OF RTE
6 THIS MORNING BUT IT BECOMES MIGRATORY THRU THE DAY. ONLY THE
LOWER SUSQ WILL HAVE A DECENT SHOT AT CLEARING OUT TODAY ON THE
DOWNHILL SIDE OF THE WESTERLY FLOW. OTHERWISE...MOSTLY CLOUDY AND
BLUSTERY IS BEST WORDING TODAY. GUSTS COULD BE INTO THE 20S AREA
WIDE AND NEAR 30MPH IN THE LAURELS. THIS COMBINE WITH THE SNOW
THERE COULD LEAD TO VERY POOR DRIVING. BUT THE SNOW INTENSITY WILL
NOT BE TOO TERRIBLE UNTIL LATER TODAY. ABOUT 4-5F IS ALL WE WILL
BE ABLE TO ADD TO MAXES TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
SHORT WAVE TROUGH SWINGS THRU THIS EVENING AND CARVES THE BASE OF
THE BIGGER TROUGH. THIS MAY LEAD TO A BRIEF PERIOD OF BETTER
ORGANIZATION TO THE UPSLOPE SNOW AND PUSH SOME ACCUMULATION OVER
THE ALLEGHENY FRONT INTO THE CENTRAL/RIDGE AND VALLEY REGION.
BUT ACCUMS IN THAT AREA WOULD BE ONLY AN INCH OR SO. IT GETS
UNIFORMLY COLDER ALL UP/DOWN THE COLUMN TONIGHT AND THE SATURATED
DGZ IS PIERCED THRU BY THE BEST UPWARD FORCING/OMEGAS. THUS...IT
SHOULD BE PRETTY EASY TO GET A FLUFFY SNOW OUT OF THE ATMOS
TONIGHT. SLR/S COULD BE 25:1 OR 30:1. SO EVEN WITHOUT SIGNIFICANT
QPF IN THE MDLS...WE SHOULD BE ON THE LOOKOUT FOR HIGHER THAN
CURRENTLY EXPECTED TOTALS. LOWS WILL DIP INTO THE SINGLE DIGITS IN
THE N/W AND WIND CHILLS GO INTO THE SINGLE DIGITS BELOW ZERO
OVERNIGHT/THURS MORNING.
AS THE TROUGH AXIS SLIDES TO THE EAST ON THURS...WE SHOULD IMPROVE
WITH SNOW SHOWERS TAPERING OFF IN THE MORNING IN THE LAURELS. BUT
IT COULD TAKE ALL DAY FOR THEM TO LIFT OUT OF THE SNOW BELT. HAVE
EXTENDED THE TIME OF THE WINT WX ADVY FOR THE LAURELS INTO THE
MIDDLE OF THE DAY THURS TO MATCH TIMES WITH OUR LK EFF ADVY. MAXES
WILL BE ONLY 12-25F WHICH ARE ABOUT 15 TO 25 DEGS BELOW NORMAL FOR
THIS TIME OF YEAR.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
*IMPACT WEATHER HIGHLIGHTS: SNOW SQUALLS POSSIBLE WITH ARCTIC
FRONT FRIDAY NIGHT-EARLY SATURDAY. FRIGID TEMPERATURES/DANGEROUS
WIND CHILLS FOR VALENTINES WEEKEND.
POLAR VORTEX DIVES FROM HUDSON BAY SOUTHEAST ACROSS QUEBEC AND
NORTHERN NEW ENGLAND THURSDAY-SUNDAY. THE GLOBAL MODELS AND
ENSEMBLE MEANS KEEP A `MILDER` TROUGH PATTERN IN PLACE OVER THE
NORTHEAST CONUS INTO NEXT WEEK.
THE FIRST SHOT OF COLD AIR ARRIVES ON THURSDAY WITH LAKE EFFECT
AND UPSLOPE SNOW SHOWERS TAPERING OFF THURSDAY NIGHT. LIGHT TO
MODERATE SNOW ACCUMULATIONS ARE LIKELY IN THE FAVORED NORTHWEST
SNOWBELT AND HIGHER TERRAIN ALONG THE ALLEGHENIES/LAUREL
HIGHLANDS.
THE COLDEST AIRMASS OF THE 2015-16 WINTER SEASON REMAINS POISED
TO ARRIVE THIS WEEKEND...AS A BLAST OF ARCTIC AIR DELIVERS A SHORT
DURATION COLD OUTBREAK TO CENTRAL PENNSYLVANIA. SNOW SQUALLS ARE
POSSIBLE WITH THE ARCTIC FRONTAL PASSAGE FRIDAY NIGHT INTO EARLY
SATURDAY.
MAX/MIN TEMPERATURE DEPARTURES OF -20 TO -25 DEGREES BELOW CLIMO
ARE FCST SATURDAY AND SUNDAY. MINIMUM TEMPERATURES SATURDAY NIGHT
INTO EARLY SUNDAY MORNING RANGE FROM AROUND 0F IN THE LOWER SUSQ.
VALLEY TO -10F IN THE NORTHWEST ALLEGHENIES. THE FRIGID TEMPERATURES
COMBINED WITH DANGEROUS WIND CHILLS /-10 TO -25 BELOW ZERO/ WILL
RESULT IN AN INCREASED RISK FOR FROSTBITE AND HYPOTHERMIA.
A SLOW MODERATION (WARMING TREND) IS EXPECTED INTO EARLY NEXT
WEEK...BUT WITH A POTENTIAL OVERRUNNING/WAA TYPE SNOW EVENT.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
12Z TAFS SENT.
EXPECT MOST OF THE AREA TO HAVE VFR CONDITIONS SHORTLY.
BULK OF THE SNOW NOW EAST OF THE AREA.
HOWEVER...BFD AND JST WILL LIKELY HAVE MVFR AND IFR
CONDITIONS WITH SNOW SHOWERS INTO THU.
GUSTY WINDS WILL PREVAIL TODAY AND THU.
FOR UNV...AND AOO...EXPECT SNOW SHOWERS TO MAKE IT BACK
INTO THE AREA AT TIMES TODAY AND AFTER SUNSET...AS COLDER
AIR WORKS INTO THE AREA.
OUTLOOK...
THU...MVFR IN -SHSN W MTNS. VFR ELSEWHERE.
FRI...MVFR IN -SHSN...MAINLY LATE WITH STRONG COLD FRONT.
SAT...MVFR IN -SHSN W MTNS. VFR OTHERWISE. WINDY.
SUN...MVFR IN -SHSN IN W MTNS EARLY...OTHERWISE VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THURSDAY FOR PAZ005.
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST THURSDAY FOR PAZ004.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THURSDAY FOR PAZ024-033.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...STEINBUGL
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
507 AM EST WED FEB 10 2016
.SYNOPSIS...
A DEEP UPPER TROUGH WILL ESTABLISH ITSELF OVER THE NORTHEASTERN
U.S. OVER THE NEXT SEVERAL DAYS. A CONSTANT NORTHWEST FLOW WILL
BRING IN THE COLDEST AIR OF THE SEASON AS WELL AS CREATE A
PROLONGED PERIOD OF SNOW SHOWERS IN THE SNOW BELT AND LAUREL
HIGHLANDS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LIGHT SNOW WINDING DOWN OVER YORK/LANCASTER COUNTIES. THE SNOW
OVER THE WEST IS STARTING TO FORM A COHERENT MASS BUT THIS MIGHT
NOT LAST LONG. THE VORT MAX CURRENTLY OVER KBUF WILL CONTINUE TO
SLIDE TO THE EAST AND POSSIBLY DIMINISH THE SNOW THIS MORNING
BEFORE IT PICKS BACK UP AGAIN LATE IN THE AFTERNOON. HRRR AND RAP
BOTH GENERATE AN E-W BAND OF SNOW ALONG AND JUST TO THE S OF RTE
6 THIS MORNING BUT IT BECOMES MIGRATORY THRU THE DAY. ONLY THE
LOWER SUSQ WILL HAVE A DECENT SHOT AT CLEARING OUT TODAY ON THE
DOWNHILL SIDE OF THE WESTERLY FLOW. OTHERWISE...MOSTLY CLOUDY AND
BLUSTERY IS BEST WORDING TODAY. GUSTS COULD BE INTO THE 20S AREA
WIDE AND NEAR 30MPH IN THE LAURELS. THIS COMBINE WITH THE SNOW
THERE COULD LEAD TO VERY POOR DRIVING. BUT THE SNOW INTENSITY WILL
NOT BE TOO TERRIBLE UNTIL LATER TODAY. ABOUT 4-5F IS ALL WE WILL
BE ABLE TO ADD TO MAXES TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
SHORT WAVE TROUGH SWINGS THRU THIS EVENING AND CARVES THE BASE OF
THE BIGGER TROUGH. THIS MAY LEAD TO A BRIEF PERIOD OF BETTER
ORGANIZATION TO THE UPSLOPE SNOW AND PUSH SOME ACCUMULATION OVER
THE ALLEGHENY FRONT INTO THE CENTRAL/RIDGE AND VALLEY REGION.
BUT ACCUMS IN THAT AREA WOULD BE ONLY AN INCH OR SO. IT GETS
UNIFORMLY COLDER ALL UP/DOWN THE COLUMN TONIGHT AND THE SATURATED
DGZ IS PIERCED THRU BY THE BEST UPWARD FORCING/OMEGAS. THUS...IT
SHOULD BE PRETTY EASY TO GET A FLUFFY SNOW OUT OF THE ATMOS
TONIGHT. SLR/S COULD BE 25:1 OR 30:1. SO EVEN WITHOUT SIGNIFICANT
QPF IN THE MDLS...WE SHOULD BE ON THE LOOKOUT FOR HIGHER THAN
CURRENTLY EXPECTED TOTALS. LOWS WILL DIP INTO THE SINGLE DIGITS IN
THE N/W AND WIND CHILLS GO INTO THE SINGLE DIGITS BELOW ZERO
OVERNIGHT/THURS MORNING.
AS THE TROUGH AXIS SLIDES TO THE EAST ON THURS...WE SHOULD IMPROVE
WITH SNOW SHOWERS TAPERING OFF IN THE MORNING IN THE LAURELS. BUT
IT COULD TAKE ALL DAY FOR THEM TO LIFT OUT OF THE SNOW BELT. HAVE
EXTENDED THE TIME OF THE WINT WX ADVY FOR THE LAURELS INTO THE
MIDDLE OF THE DAY THURS TO MATCH TIMES WITH OUR LK EFF ADVY. MAXES
WILL BE ONLY 12-25F WHICH ARE ABOUT 15 TO 25 DEGS BELOW NORMAL FOR
THIS TIME OF YEAR.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
*IMPACT WEATHER HIGHLIGHTS: SNOW SQUALLS POSSIBLE WITH ARCTIC
FRONT FRIDAY NIGHT-EARLY SATURDAY. FRIGID TEMPERATURES/DANGEROUS
WIND CHILLS FOR VALENTINES WEEKEND.
POLAR VORTEX DIVES FROM HUDSON BAY SOUTHEAST ACROSS QUEBEC AND
NORTHERN NEW ENGLAND THURSDAY-SUNDAY. THE GLOBAL MODELS AND
ENSEMBLE MEANS KEEP A `MILDER` TROUGH PATTERN IN PLACE OVER THE
NORTHEAST CONUS INTO NEXT WEEK.
THE FIRST SHOT OF COLD AIR ARRIVES ON THURSDAY WITH LAKE EFFECT
AND UPSLOPE SNOW SHOWERS TAPERING OFF THURSDAY NIGHT. LIGHT TO
MODERATE SNOW ACCUMULATIONS ARE LIKELY IN THE FAVORED NORTHWEST
SNOWBELT AND HIGHER TERRAIN ALONG THE ALLEGHENIES/LAUREL
HIGHLANDS.
THE COLDEST AIRMASS OF THE 2015-16 WINTER SEASON REMAINS POISED
TO ARRIVE THIS WEEKEND...AS A BLAST OF ARCTIC AIR DELIVERS A SHORT
DURATION COLD OUTBREAK TO CENTRAL PENNSYLVANIA. SNOW SQUALLS ARE
POSSIBLE WITH THE ARCTIC FRONTAL PASSAGE FRIDAY NIGHT INTO EARLY
SATURDAY.
MAX/MIN TEMPERATURE DEPARTURES OF -20 TO -25 DEGREES BELOW CLIMO
ARE FCST SATURDAY AND SUNDAY. MINIMUM TEMPERATURES SATURDAY NIGHT
INTO EARLY SUNDAY MORNING RANGE FROM AROUND 0F IN THE LOWER SUSQ.
VALLEY TO -10F IN THE NORTHWEST ALLEGHENIES. THE FRIGID TEMPERATURES
COMBINED WITH DANGEROUS WIND CHILLS /-10 TO -25 BELOW ZERO/ WILL
RESULT IN AN INCREASED RISK FOR FROSTBITE AND HYPOTHERMIA.
A SLOW MODERATION (WARMING TREND) IS EXPECTED INTO EARLY NEXT
WEEK...BUT WITH A POTENTIAL OVERRUNNING/WAA TYPE SNOW EVENT.
&&
.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
EXPECT MOST OF THE AREA TO HAVE VFR CONDITIONS SHORTLY.
BULK OF THE SNOW NOW EAST OF THE AREA.
HOWEVER...BFD AND JST WILL LIKELY HAVE MVFR AND IFR
CONDITIONS WITH SNOW SHOWERS INTO THU.
GUSTY WINDS WILL PREVAIL TODAY AND THU.
FOR UNV...AND AOO...EXPECT SNOW SHOWERS TO MAKE IT BACK
INTO THE AREA AT TIMES TODAY AND AFTER SUNSET...AS COLDER
AIR WORKS INTO THE AREA.
OUTLOOK...
THU...MVFR IN -SHSN W MTNS. VFR ELSEWHERE.
FRI...MVFR IN -SHSN...MAINLY LATE WITH STRONG COLD FRONT.
SAT...MVFR IN -SHSN W MTNS. VFR OTHERWISE. WINDY.
SUN...MVFR IN -SHSN IN W MTNS EARLY...OTHERWISE VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THURSDAY FOR PAZ005.
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST THURSDAY FOR PAZ004.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THURSDAY FOR PAZ024-033.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...STEINBUGL
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
359 AM EST WED FEB 10 2016
.SYNOPSIS...
A DEEP UPPER TROUGH WILL ESTABLISH ITSELF OVER THE NORTHEASTERN
U.S. OVER THE NEXT SEVERAL DAYS. A CONSTANT NORTHWEST FLOW WILL
BRING IN THE COLDEST AIR OF THE SEASON AS WELL AS CREATE A
PROLONGED PERIOD OF SNOW SHOWERS IN THE SNOW BELT AND LAUREL
HIGHLANDS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LIGHT SNOW WINDING DOWN OVER YORK/LANCASTER COUNTIES. THE SNOW
OVER THE WEST IS STARTING TO FORM A COHERENT MASS BUT THIS MIGHT
NOT LAST LONG. THE VORT MAX CURRENTLY OVER KBUF WILL CONTINUE TO
SLIDE TO THE EAST AND POSSIBLY DIMINISH THE SNOW THIS MORNING
BEFORE IT PICKS BACK UP AGAIN LATE IN THE AFTERNOON. HRRR AND RAP
BOTH GENERATE AN E-W BAND OF SNOW ALONG AND JUST TO THE S OF RTE
6 THIS MORNING BUT IT BECOMES MIGRATORY THRU THE DAY. ONLY THE
LOWER SUSQ WILL HAVE A DECENT SHOT AT CLEARING OUT TODAY ON THE
DOWNHILL SIDE OF THE WESTERLY FLOW. OTHERWISE...MOSTLY CLOUDY AND
BLUSTERY IS BEST WORDING TODAY. GUSTS COULD BE INTO THE 20S AREA
WIDE AND NEAR 30MPH IN THE LAURELS. THIS COMBINE WITH THE SNOW
THERE COULD LEAD TO VERY POOR DRIVING. BUT THE SNOW INTENSITY WILL
NOT BE TOO TERRIBLE UNTIL LATER TODAY. ABOUT 4-5F IS ALL WE WILL
BE ABLE TO ADD TO MAXES TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
SHORT WAVE TROUGH SWINGS THRU THIS EVENING AND CARVES THE BASE OF
THE BIGGER TROUGH. THIS MAY LEAD TO A BRIEF PERIOD OF BETTER
ORGANIZATION TO THE UPSLOPE SNOW AND PUSH SOME ACCUMULATION OVER
THE ALLEGHENY FRONT INTO THE CENTRAL/RIDGE AND VALLEY REGION.
BUT ACCUMS IN THAT AREA WOULD BE ONLY AN INCH OR SO. IT GETS
UNIFORMLY COLDER ALL UP/DOWN THE COLUMN TONIGHT AND THE SATURATED
DGZ IS PIERCED THRU BY THE BEST UPWARD FORCING/OMEGAS. THUS...IT
SHOULD BE PRETTY EASY TO GET A FLUFFY SNOW OUT OF THE ATMOS
TONIGHT. SLR/S COULD BE 25:1 OR 30:1. SO EVEN WITHOUT SIGNIFICANT
QPF IN THE MDLS...WE SHOULD BE ON THE LOOKOUT FOR HIGHER THAN
CURRENTLY EXPECTED TOTALS. LOWS WILL DIP INTO THE SINGLE DIGITS IN
THE N/W AND WIND CHILLS GO INTO THE SINGLE DIGITS BELOW ZERO
OVERNIGHT/THURS MORNING.
AS THE TROUGH AXIS SLIDES TO THE EAST ON THURS...WE SHOULD IMPROVE
WITH SNOW SHOWERS TAPERING OFF IN THE MORNING IN THE LAURELS. BUT
IT COULD TAKE ALL DAY FOR THEM TO LIFT OUT OF THE SNOW BELT. HAVE
EXTENDED THE TIME OF THE WINT WX ADVY FOR THE LAURELS INTO THE
MIDDLE OF THE DAY THURS TO MATCH TIMES WITH OUR LK EFF ADVY. MAXES
WILL BE ONLY 12-25F WHICH ARE ABOUT 15 TO 25 DEGS BELOW NORMAL FOR
THIS TIME OF YEAR.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
*IMPACT WEATHER HIGHLIGHTS: SNOW SQUALLS POSSIBLE WITH ARCTIC
FRONT FRIDAY NIGHT-EARLY SATURDAY. FRIGID TEMPERATURES/DANGEROUS
WIND CHILLS FOR VALENTINES WEEKEND.
POLAR VORTEX DIVES FROM HUDSON BAY SOUTHEAST ACROSS QUEBEC AND
NORTHERN NEW ENGLAND THURSDAY-SUNDAY. THE GLOBAL MODELS AND
ENSEMBLE MEANS KEEP A `MILDER` TROUGH PATTERN IN PLACE OVER THE
NORTHEAST CONUS INTO NEXT WEEK.
THE FIRST SHOT OF COLD AIR ARRIVES ON THURSDAY WITH LAKE EFFECT
AND UPSLOPE SNOW SHOWERS TAPERING OFF THURSDAY NIGHT. LIGHT TO
MODERATE SNOW ACCUMULATIONS ARE LIKELY IN THE FAVORED NORTHWEST
SNOWBELT AND HIGHER TERRAIN ALONG THE ALLEGHENIES/LAUREL
HIGHLANDS.
THE COLDEST AIRMASS OF THE 2015-16 WINTER SEASON REMAINS POISED
TO ARRIVE THIS WEEKEND...AS A BLAST OF ARCTIC AIR DELIVERS A SHORT
DURATION COLD OUTBREAK TO CENTRAL PENNSYLVANIA. SNOW SQUALLS ARE
POSSIBLE WITH THE ARCTIC FRONTAL PASSAGE FRIDAY NIGHT INTO EARLY
SATURDAY.
MAX/MIN TEMPERATURE DEPARTURES OF -20 TO -25 DEGREES BELOW CLIMO
ARE FCST SATURDAY AND SUNDAY. MINIMUM TEMPERATURES SATURDAY NIGHT
INTO EARLY SUNDAY MORNING RANGE FROM AROUND 0F IN THE LOWER SUSQ.
VALLEY TO -10F IN THE NORTHWEST ALLEGHENIES. THE FRIGID TEMPERATURES
COMBINED WITH DANGEROUS WIND CHILLS /-10 TO -25 BELOW ZERO/ WILL
RESULT IN AN INCREASED RISK FOR FROSTBITE AND HYPOTHERMIA.
A SLOW MODERATION (WARMING TREND) IS EXPECTED INTO EARLY NEXT
WEEK...BUT WITH A POTENTIAL OVERRUNNING/WAA TYPE SNOW EVENT.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
WIDE RANGE OF CONDITIONS EXPECTED OVERNIGHT.
06Z TAFS SENT.
EARLIER DISCUSSION BELOW.
IFR/LIFR CONDITIONS WILL REMAIN WIDESPREAD...ESPECIALLY ALONG AND
SOUTHEAST OF I 80. THE DRIER FLOW IS MOVING IN FROM THE
NORTHEAST...WHICH WILL SIGNAL AN END TO MOST OF THE SNOW
SHOWERS...OUTSIDE OF THE LAKE AND TOPOGRAPHIC EFFECTED REGIONS. SNOW
WILL CONTINUE TO TAPER TO FLURRIES AS THE EVENING
CONTINUES...CIGS WILL REMAIN LOW THROUGH THE EVENING...BUT AS
WESTERLY FLOW INCREASES A BIT OVERNIGHT CIGS WILL IMPROVE AS WELL
IN CENTRAL AND EASTERN AREAS. LOWER SUSQ WILL IMPROVE TO VFR WITH
CENTRAL MTNS HOLDING ON TO AN MVFR DECK. WESTERN HIGHER TERRAIN
WILL CONTINUE TO SEE SOME SNOWFLAKES IN THE AIR WITH UPSLOPE FLOW
KEEPING MAINLY IFR CIGS IN PLACE. EXPECT CIGS TO IMPROVE TOWARD
MORNING.
OUTLOOK...
WED...MAINLY IFR IN SNOW WRN AIRSPACE. MVFR-VFR CIGS
CENTRAL/EAST.
THU-SAT...MVFR IN -SHSN W MTNS. VFR ELSEWHERE.
SUN...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THURSDAY FOR PAZ005.
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST THURSDAY FOR PAZ004.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THURSDAY FOR PAZ024-033.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...STEINBUGL
AVIATION...CERU/MARTIN/RXR
AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION CAN BE SEEN AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
Area Forecast Discussion
National Weather Service Spokane WA
215 PM PST THU FEB 11 2016
.SYNOPSIS...
A warm front lifts into the Inland Northwest through tonight.
This will spread a chance of rain across much of the area. Snow
will generally fall only in the higher mountains. The exception
will be in the valleys near the north Cascades. A cold front
passes later Friday, with continued precipitation chances and
slightly lower snow levels. Unsettled weather will continue
through the weekend into early next week with valley rain, high
mountain snow and breezy winds expected. Temperatures will be
quite mild on Monday with many locations seeing highs in the mid
50s to low 60s.
&&
.DISCUSSION...
Tonight through Saturday: The Inland NW will be in a wetter
pattern as a frontal wave moves through the region. Tonight a warm
front draped across southern WA and the lower ID Panhandle lifts
toward the northern mountains. Deepening and moistening isentropic
ascent will lead to broad precipitation threat across the Inland
NW this evening. However the highest risk will be along and north
of I-90 and lowest toward the Palouse into the L-C Valley.
Precipitation will largely fall as rain in the valleys, leaving
snow for the higher mountains. The main exception remains near the
Methow Valley where the warm air is not too deep and precipitation
may fall as a rain/snow mix or all snow. This may result in an
inch or so of snow through the night. Otherwise models don`t show
the precipitation to be too significant in terms of amounts, with
most areas seeing somewhere around a tenth of an inch through
Friday morning. Also, while PoPs will be relatively high, the
precipitation may be periodic, meaning it doesn`t look organized
enough to say the entire period will see steady rain. Between the
precipitation there will be the potential for fog. Yet confidence
in coverage and intensity in low, so it left as patchy.
Going into Friday the warm front lingers near the northern-tier,
while a cold front comes toward the Cascades in the afternoon. In
the morning some models show drier air across south-central and
southeastern WA and the lower Panhandle. Others are not as ready
to bring drier air in. A threat of precipitation will continue
across region, however the highest risk across the Cascades and
northern mountain zones. Between Friday afternoon and evening the
cold front crosses the Cascades and advances toward the ID/WA
border. This will revitalize the threat of precipitation The
Cascades will seeing the highest risk in the afternoon, while
chances wane there through the evening. Chances will increase
farther east through the afternoon and peak in the evening.
Between late evening and overnight the broader threat retreats to
the mountains, while the lowlands dry out. The incoming cold front
will also lead to some breezy conditions by Friday afternoon,
generally highest over south-central to southeastern WA into the
Idaho Palouse. Speeds on the order of 5 to 15 mph with gusts to 25
mph will be possible.
On Saturday an upper trough continues to migrate through the
eastern third of WA and north ID early, while the next warm front
starts to impinge on the Cascades in the afternoon. This set-up
will keep the the threat of showers alive across the region. With
the highest risk in the Cascades and the northeast WA and ID
Panhandle mountains, as well the rising terrain over the eastern
Columbia Basin. The lowest risk will be in the lee of the Cascades
and deeper Columbia Basin. Winds will be a bit stronger Saturday
afternoon, especially south-central and southeast and eastern-
central Washington into the Idaho Palouse. Speeds of 10 to 20 mph,
with gusts to 30 mph will be possible. This should allow for most
areas to come out of the Air Stagnation Advisory. The main
exception will be near the Cascade valleys/Okanogan Valley where
winds and mixing will be less. /J. Cote`
Saturday night through Thursday...The models are in relatively
good agreement through about 12z Wednesday before breaking down
Wednesday and Thursday. Zonal flow or weak ridging will be over
the region through the forecast period. The westerly flow will tap
into deep Pacific moisture with several weak waves that are
expected to move through the main flow. This will result in a warm
and fairly wet forecast through the extended period. Snow levels
Saturday night will be around 3k feet for the north and 4k feet
across the south, but rapidly increase by Sunday afternoon to 5-6k
feet and to 6-7k feet by Monday. So the higher elevations of the
Cascades and the northern and Panhandle mountains could see 3-6
inches of wet snow Saturday night, otherwise precipitation will be
as rain with high elevations snow the remainder of the week.
Precipitation amounts from Saturday night through Tuesday could
reach 0.25-0.50 for the lower elevations and 0.50-1.00 or a liitle
more for the mountains. Near the Cascade crest 1.0 to 1.5 inches
will be possible. Temperatures on Sunday will be in the 40s and
50s, which will be about 5 degrees above normal. Then the
temperatures will increase Monday and Tuesday by another 5-10
degrees. The warm temperatures and rain will almost certainly
result in good snow melt and rises on area rivers.
We will have to pay special attention to Monday. Temperatures are
expected to 10-15 degrees above normal and dew points will be
well into the 40s and 50s. A surface low will develop east of the
Continental Divide and with weak surface high pressure along the
coast the surface gradient will increase. In addition 850mb winds
will increase to around 35-40kts. This will result in southwest
winds 20-30 mph with gust 30-40 mph across the mountain tops, the
Columbia basin and the Palouse area. Gusty winds, warm
temperatures and high dew points will result in rapid snow melt.
The focus will be across the Waterville Plateau, some of he
mountain valleys, and across the Idaho Palouse where the low
elevation snow will likely melt at a rapid rate. Model hydrographs
show rapid rises on almost all rivers and streams, but areas of
concern will be the Palouse basin, and the Coeur D`Alene basin
where the rivers may bump up against action stage. Up on the
Waterville Plateau there is plenty of snow to melt and run off.
Palisades creek will see some significant rises. In addition snow
melt will likely cause nuisance flooding along secondary roads and
especially in area where culverts cross the road. We will issue a
hydrologic outlook to keep up with situational awareness through
the weekend.
Wednesday and Thursday...The models break down as far as
consistency goes. Some models try to bring an upper level trough
through the region late Wednesday and Thursday, while others want
to under-cut the ridge with the low going into California ans
still others have something some where in between. I chose to keep
a low end chance of rain or showers in the forecast for now with
temperatures cooling off but remaining above normal. Tobin
&&
.AVIATION...
18Z TAFS: Little change to the previous thinking for the TAFs
over the next 24 hours. Deep moisture will ride up the backside of
the ridge as warm front moved into the region and will result in
increasing chance of light precipitation across the western TAF
sites by this afternoon and the easter TAF sites by this evening.
Conditions for KCOE-KSFF-KGEG corridor have improved early this
afternoon as stratus/fog is beginning to dissipate with VFR
conditions expected until 03-04z. Then increasing moisture and
chances for precipitaiton will again lower conditions to MVFR/IFR
and possibly LIFR through the night. For KLWS-KPUW mainly VFR
conditions will be in place through 18z Friday. Some -shra is
possible between 02z-12z with a lowering deck but still VFR.
Further to the west conditions will remain VFR at KMWH-KEAT with
the deck lowering to 050-070. Precipitation chances will increase
after 02z with cigs/vsby dropping down to MVFR and and briefly
IFR. Then fog and stratus will likely form near KEAT with IFR
cigs/vsby after 12-14z. Tobin
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 38 47 34 45 35 46 / 60 50 60 40 60 40
Coeur d`Alene 37 47 36 45 34 45 / 60 60 70 60 70 60
Pullman 41 53 38 47 37 49 / 30 50 70 40 90 60
Lewiston 43 57 41 54 42 55 / 20 30 50 30 80 50
Colville 34 40 33 43 33 41 / 80 80 50 50 60 30
Sandpoint 34 40 34 41 33 40 / 80 80 90 60 70 60
Kellogg 36 42 35 39 33 40 / 70 60 90 80 90 80
Moses Lake 38 49 34 51 37 52 / 50 50 20 10 40 20
Wenatchee 34 44 33 46 33 46 / 80 40 20 10 50 30
Omak 35 42 30 41 30 39 / 80 60 20 20 40 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Air Stagnation Advisory until 10 AM PST Saturday for Moses Lake
Area-Northeast Mountains-Okanogan Highlands-Upper Columbia
Basin-Waterville Plateau-Wenatchee Area.
Air Stagnation Advisory until 10 AM PST Tuesday for East Slopes
Northern Cascades-Okanogan Valley.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
104 PM PST THU FEB 11 2016
.SYNOPSIS...
...Updated aviation discussion...
A warm front lifts into the Inland Northwest through
tonight. This will spreading a chance of rain across much of the
area. Snow will generally fall only in the higher mountains. The
except near will in the valleys near the north Cascades. A cold
front passes later Friday, with continued precipitation chances
and slightly lower snow levels. Unsettled weather will continue
through the weekend into early next week with valley rain, high
mountain snow and breezy winds expected. Temperatures will be
quite mild on Monday with many locations seeing highs in the mid
50s to low 60s.
&&
.DISCUSSION...
Morning update: a warm front stretches from the lower Panhandle to
northwest Washington, with moisture spreading in from the
west-southwest. This will provide continued precipitation chances
from the Cascades to southeast Washington today. This will mainly
fall as rain, with the main snow threat in the higher mountains.
The exception will be across the northern Cascades, in places such
as the Methow Valley. While surface temperatures are slightly
above freezing, the mild air is not very deep. Thus a rain/snow
mix or all snow in the higher valleys is possible. Accumulations
should be limited to less than an inch here. Elsewhere look for
mainly sprinkles toward the northeast WA and north ID, but as we
go into late this afternoon into tonight the atmospheric layer
will begin to moisten up and there will be better precipitation
chances throughout the northern two-third of the Inland NW...i.e.
along and north of I-90.
Main adjustments: I extended the patchy fog threat into the
afternoon. The dense fog has been on the decline but given the
moist boundary layer and lack of significant mixing, there will
likely be some patches of fog out there through the afternoon. I
also reduced high temperatures a bit across the northern. The
tricky part is if that warm front shifts north and winds turn
southerly, some of the milder air to the south may get further
north. However given the persistent low clouds and lack of
significant mixing, it seemed some of locations would not be able
to achieve the previously forecast highs. /J. Cote`
&&
.AVIATION...
18Z TAFS: Little change to the previous thinking for the TAFs
over the next 24 hours. Deep moisture will ride up the backside of
the ridge as warm front moved into the region and will result in
increasing chance of light precipitation across the western TAF
sites by this afternoon and the easter TAF sites by this evening.
Conditions for KCOE-KSFF-KGEG corridor have improved early this
afternoon as stratus/fog is beginning to dissipate with VFR
conditions expected until 03-04z. Then increasing moisture and
chances for precipitaiton will again lower conditions to MVFR/IFR
and possibly LIFR through the night. For KLWS-KPUW mainly VFR
conditions will be in place through 18z Friday. Some -shra is
possible between 02z-12z with a lowering deck but still VFR.
Further to the west conditions will remain VFR at KMWH-KEAT with
the deck lowering to 050-070. Precipitation chances will increase
after 02z with cigs/vsby dropping down to MVFR and and briefly
IFR. Then fog and stratus will likely form near KEAT with IFR
cigs/vsby after 12-14z. Tobin
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 43 38 47 34 45 35 / 10 60 70 50 40 60
Coeur d`Alene 44 37 47 36 45 34 / 10 70 70 70 60 70
Pullman 51 40 52 38 47 36 / 20 30 40 60 40 70
Lewiston 54 44 57 41 54 40 / 10 20 30 50 30 60
Colville 40 34 41 33 43 35 / 10 80 80 50 50 60
Sandpoint 41 35 41 34 42 34 / 10 80 80 90 60 70
Kellogg 41 37 43 35 39 33 / 10 70 60 90 80 90
Moses Lake 46 38 49 34 52 38 / 20 50 40 30 10 40
Wenatchee 40 34 44 33 47 35 / 50 80 50 20 10 50
Omak 38 35 37 30 42 33 / 30 90 70 30 20 40
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Air Stagnation Advisory until 10 AM PST Saturday for East Slopes
Northern Cascades-Moses Lake Area-Northeast Mountains-
Okanogan Highlands-Okanogan Valley-Upper Columbia Basin-
Waterville Plateau-Wenatchee Area.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
1028 AM PST THU FEB 11 2016
.SYNOPSIS...
A warm front lifts into the Inland Northwest through tonight. This
will spreading a chance of rain across much of the area. Snow
will generally fall only in the higher mountains. The except near
will in the valleys near the north Cascades. A cold front passes
later Friday, with continued precipitation chances and slightly
lower snow levels. Unsettled weather will continue through the
weekend into early next week with valley rain, high mountain snow
and breezy winds expected. Temperatures will be quite mild on
Monday with many locations seeing highs in the mid 50s to low 60s.
&&
.DISCUSSION...
Morning update: a warm front stretches from the lower Panhandle to
northwest Washington, with moisture spreading in from the
west-southwest. This will provide continued precipitation chances
from the Cascades to southeast Washington today. This will mainly
fall as rain, with the main snow threat in the higher mountains.
The exception will be across the northern Cascades, in places such
as the Methow Valley. While surface temperatures are slightly
above freezing, the mild air is not very deep. Thus a rain/snow
mix or all snow in the higher valleys is possible. Accumulations
should be limited to less than an inch here. Elsewhere look for
mainly sprinkles toward the northeast WA and north ID, but as we
go into late this afternoon into tonight the atmospheric layer
will begin to moisten up and there will be better precipitation
chances throughout the northern two-third of the Inland NW...i.e.
along and north of I-90.
Main adjustments: I extended the patchy fog threat into the
afternoon. The dense fog has been on the decline but given the
moist boundary layer and lack of significant mixing, there will
likely be some patches of fog out there through the afternoon. I
also reduced high temperatures a bit across the northern. The
tricky part is if that warm front shifts north and winds turn
southerly, some of the milder air to the south may get further
north. However given the persistent low clouds and lack of
significant mixing, it seemed some of locations would not be able
to achieve the previously forecast highs. /J. Cote`
&&
.AVIATION...
18Z TAFS: Little change to the previous thinking for the TAFs
over the next 24 hours. Deep moisture will ride up the backside of
the ridge as warm front moved into the region and will result in
increasing chance of light precipitation across the western TAF
sites by this afternoon and the easter TAF sites by this evening.
IFR/LIFR cigs/vsby will remain in place for the KCOE-KSFF-KGEG
corridor through early this evening as stratus/fog is entrenched
over the region. For KLWS-KPUW mainly VFR conditions will be in
place through 18z Friday. Some -shra is possible between 02z-12z
with a lowering deck but still VFR. Further to the west conditions
will remain VFR with the deck lowering to 040-050. Precipitation
chances will increase after 02z with cigs/vsby dropping down to
MVFR and and briefly IFR. Then fog and stratus will likely form
near KEAT with IFR cigs/vsby after 12-14z. Tobin
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 43 38 47 34 45 35 / 10 60 70 50 40 60
Coeur d`Alene 44 37 47 36 45 34 / 10 70 70 70 60 70
Pullman 51 40 52 38 47 36 / 20 30 40 60 40 70
Lewiston 54 44 57 41 54 40 / 10 20 30 50 30 60
Colville 40 34 41 33 43 35 / 10 80 80 50 50 60
Sandpoint 41 35 41 34 42 34 / 10 80 80 90 60 70
Kellogg 41 37 43 35 39 33 / 10 70 60 90 80 90
Moses Lake 46 38 49 34 52 38 / 20 50 40 30 10 40
Wenatchee 40 34 44 33 47 35 / 50 80 50 20 10 50
Omak 38 35 37 30 42 33 / 30 90 70 30 20 40
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Air Stagnation Advisory until 10 AM PST Saturday for East Slopes
Northern Cascades-Moses Lake Area-Northeast Mountains-
Okanogan Highlands-Okanogan Valley-Upper Columbia Basin-
Waterville Plateau-Wenatchee Area.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
949 AM PST THU FEB 11 2016
.SYNOPSIS...
A warm front will move across the Inland Northwest today and
tonight spreading a chance of rain across much of the area with
snow levels at the highest mountain elevation except near the
north Cascades. This front will be followed by the passage of a
cold front on Friday which will bring another chance of
precipitation to much of the area as well as slightly lower snow
levels. Unsettled weather will continue through the weekend into
early next week with valley rain, high mountain snow and breezy
winds expected. Temperatures will be quite mild on Monday with
many locations seeing highs in the mid 50s to low 60s.
&&
.DISCUSSION...
Today and tonight...The weather during this period will generally
revolve around a developing warm front. As of 2am, the water vapor
looper was showing a broad swath of moisture oriented from NNE-SSW
right off the coast. Meanwhile the upper level ridge of high
pressure remains poised over the Inland NW. The ridge is expected
to amplify slightly over the area today and tonight, as height
falls continue develop off the coast. Despite the presence of the
ridge we should see the first chance of precipitation this week,
the question is how soon will it develop and what will most of it
fall as. Looking closely at the latest radar mosaics it appears
the front will come through in two swaths. The first was
responsible for the east-west band of light echoes extending along
the WA/OR border and moving slowly northeastward. This one will
likely weaken as it moves farther northward with weakening
isentropic ascent, especially over the eastern third of Washington
and north Idaho. If anything falls out of this band it will likely
be very light. Over central Washington, the chances for measurable
precipitation are a little better due to slightly deeper moisture
combined with weak upslope flow into the Cascades. We suspect most
of the precipitation will fall as rain, however north of Lake
Chelan current wet-bulb temperatures are below freezing and they
may not climb much this morning. So we expect to see primarily
snow. The second surge of precipitation will bring a much better
chance of measurable precipitation. This wave is likely a
reflection of a compact shortwave located over northern California
moving steadily northward. The HRRR suggests this second band will
track into the Wenatchee and Moses Lake area around midday and
then into NE Washington and north Idaho by late afternoon or early
evening. Snow levels climb steadily with this portion of the warm
front. Wet-bulb zero heights reach 6000 feet or higher across the
entire forecast area save a small portion of the north Cascades
mainly impacting the Methow Valley. It`s a tough call as to how
effective the cold air damming will be in this area as the
surrounding air mass is awfully warm. The 850 mb flow maintains a
weak upslope orientation at least through early Friday which is
favorable for keeping snow levels locally down to the valley
floor, however surface temperature per bufkit profiles hover near
or slightly above freezing. We put several inches of snow in the
forecast across the upper Methow Valley however that`s assuming
any snow which falls is able to accumulate rather than melting as
it falls. Confidence is not high due to the precarious temperature
profiles. Elsewhere we are much more confident about primarily a
rain event. Rainfall totals should range from .15-35 inches across
the northern mountains and extending into the northern Idaho
Panhandle, with lighter amounts across southern Washington and the
central Panhandle. Near the Cascades, precipitation amounts could
range from 0.30-0.70 inches.
For Friday, the ridge finally gives way and a sw-ne oriented upper
level jet pokes into the southern portions of the region by
midday. This will turn the steady warm frontal precipitation to
more of a showery regime with most of the precipitation occurring
near the cold front. The cold front will likely end the
precipitation threat in the lee of the Cascades during the morning
hours as the upslope flow turns to a downslope westerly regime.
Meanwhile we expect the shower coverage to increase over the
eastern third of Washington and over the Panhandle during the
afternoon as the front destabilizes the atmosphere and enhances
any orographic ascent. Generally speaking the precipitation
amounts from the cold front will be lighter than whats produced
from the warm front.
Temperatures will remain milder both days
over the eastern third of Washington and the Idaho Panhandle with
highs in the 40s to middle 50s. Cooler temperatures will remain a
fixture over central Washington today due to the cold air damming
with highs in the 30s to lower 40s. The cold front should enhance
mixing on Friday bringing an end to the inversions with highs
climbing into the upper 30s to middle 40s. fx
Friday night through Wednesday...A mild and unsettled weather
pattern is expected this weekend through at least the middle of
next week. Initially a slightly cooler air mass will move in
Friday night and Saturday as an upper trough passes through. Mid
level westerly flow will favor most of these showers for the
Cascade crest and Idaho Panhandle. Snow levels by Saturday
morning lower to 3000-4000 feet with snow showers expected over
the mountain passes. Then an atmospheric river of subtropical
moisture becomes aimed at the area Saturday night into Sunday.
This will bring more rain and snow with snow levels rapidly rising
from 2500-4000 feet initially early Sunday to 6000-7000 feet
Monday as a warm front passes through. The atmospheric river
begins to lift north Sunday night into Monday to near or just
north of the Canadian border by Monday afternoon. Strong mid
level westerly flow throughout this event will favor moderate to
heavy precipitation for the Cascade crest and in the mountains of
the Idaho Panhandle with added orographic lift...with mainly
light amounts over Central and Eastern Washington as a strong rain
shadow develops. Meanwhile Monday into Tuesday a surface low
tracking into southern BC will result in a strengthening south-
southwest winds which combined with the warmer air mass will lead
to increased snow melt for areas that have snow currently. 850mb
winds increasing to 30-45 kts will likely result in breezy to
windy conditions over the region...especially the Upper Columbia
Basin, Spokane area, and Palouse. JW
&&
.AVIATION...
18Z TAFS:
Little change to the previous thinking for the TAFs over the next
24 hours. Deep moisture will ride up the backside of the ridge as
warm front moved into the region and will result in increasing
chance of light precipitation across the western TAF sites by
this afternoon and the easter TAF sites by this evening. IFR/LIFR
cigs/vsby will remain in place for the KCOE-KSFF-KGEG corridor
through early this evening as stratus/fog is entrenched over the
region. For KLWS-KPUW mainly VFR conditions will be in place
through 18z Friday. Some -shra is possible between 02z-12z with a
lowering deck but still VFR. Further to the west conditions will
remain VFR with the deck lowering to 040-050. Precipitation
chances will increase after 02z with cigs/vsby dropping down to
MVFR and and briefly IFR. Then fog and stratus will likely form
near KEAT with IFR cigs/vsby after 12-14z. Tobin
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 34 46 38 48 34 45 / 10 20 70 70 70 40
Coeur d`Alene 34 46 38 47 36 44 / 10 20 70 70 80 60
Pullman 37 51 42 52 37 47 / 10 10 20 50 60 40
Lewiston 42 55 44 57 41 53 / 0 10 20 40 50 40
Colville 32 41 35 42 33 42 / 10 20 80 60 70 50
Sandpoint 31 43 36 43 34 41 / 10 20 90 70 90 60
Kellogg 36 43 37 44 35 39 / 20 20 70 60 90 80
Moses Lake 33 46 37 48 34 49 / 0 20 40 50 30 10
Wenatchee 33 40 35 44 32 45 / 10 60 80 40 30 10
Omak 30 37 34 38 30 41 / 10 40 80 40 30 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Air Stagnation Advisory until 10 AM PST Saturday for East Slopes
Northern Cascades-Moses Lake Area-Northeast Mountains-
Okanogan Highlands-Okanogan Valley-Upper Columbia Basin-
Waterville Plateau-Wenatchee Area.
&&
$$
AREA FORECAST DISCUSSION
NWS PORTLAND OR
838 AM PST WED FEB 10 2016
.SYNOPSIS...MILD AIR MASS TO REMAIN OVER THE REGION THROUGH FRI.
WEAK FRONTS OFFSHORE WILL BRUSH THE NW TODAY AND THU...WITH VARIABLE
CLOUDINESS ACROSS THE REGION...ALONG WITH SOME SPOTTY LIGHT RAIN
ALONG THE COAST AND POSSIBLY INLAND. THAT CHANGES BY FRI...AS FIRST
IN A SERIES OF FRONTS PUSH INTO THE PAC NW. SHOWERY ON SATURDAY...BUT
MORE RAIN ARRIVES ON SUNDAY.
&&
.SHORT TERM...TODAY THROUGH SATURDAY...SATELLITE IMAGERY THIS MORNING
SHOWS A WEAKENING MID LEVEL FRONT SLOWLY SHIFTING EASTWARD INTO THE
PACIFIC NORTHWEST. A FEW SHOWERS HAVE DEVELOPED ALONG AN 850MB
BOUNDARY ACROSS FAR NORTHWEST OREGON AND SOUTHWEST WASHINGTON. THIS
BOUNDARY IS EXPECTED TO WEAKEN AS IT SHIFTS INLAND SO HAVE KEPT MOST
LOCATIONS WITH CHANCE OR SLIGHT CHANCE POPS FOR TODAY. GIVEN THE
AFOREMENTIONED BOUNDARY WILL HANG ACROSS THE AREA OVERNIGHT...CANNOT
RULE OUT A LIGHT SHOWER OR TWO...BUT IN GENERAL...ANY RAIN THAT FALLS
SHOULD BE LIGHT AND RATHER ISOLATED.
A LOW PRESSURE SYSTEM IS THEN FORECAST TO DEEPEN AS IT MOVES
NORTHWARD ALONG 140W ON THURSDAY. THIS WILL SPREAD A WARM FRONT
NORTHWARD AND INCREASE RAIN CHANCES ACROSS THE AREA ON THURSDAY. AT
THIS POINT...THE DEEPEST MOISTURE AND BEST DYNAMICS WILL PRIMARILY
STAY OFFSHORE SO KEPT THE TREND OF KEEPING THE HIGHEST POPS ACROSS
OUR FAR NORTHWEST ZONES AND LOWEST POPS ACROSS LANE AND LINN
COUNTIES. NONETHELESS...IT LOOKS LIKE A GOOD PORTION OF THE FORECAST
AREA WILL SEE AT LEAST SOME RAIN ON THURSDAY...ESPECIALLY DURING THE
MIDDAY AND AFTERNOON HOURS.
THE TRAILING COLD FRONT SHOULD THEN PUSH INTO THE PACIFIC NORTHWEST
AT SOME POINT THURSDAY NIGHT OR FRIDAY MORNING. THIS WILL LIKELY
SPREAD ANOTHER ROUND OF RAIN INTO THE AREA DURING THIS PERIOD. SNOW
LEVELS SHOULD LOWERING INTO THE 4000-4500 FT RANGE ON FRIDAY. AS POST
FRONTAL SHOWERS SPREAD INTO THE PACIFIC NORTHWEST LATE FRIDAY AND
FRIDAY NIGHT...SNOW LEVELS MAY LOWER ANOTHER 500 FT OR SO AND BRING
SOME IMPACTS TO TRAVEL IN THE CASCADES. SNOW ACCUMULATIONS IN THE
CASCADES APPEAR LIKELY TO REMAIN UNDER WINTER WX ADVISORY CRITERIA
THOUGH.
A WARMER AND WETTER STORM SYSTEM APPEARS ON TRACK FOR SATURDAY NIGHT.
/NEUMAN
.LONG TERM...SATURDAY THROUGH TUESDAY...
COOLER ON SATURDAY...WITH SHOWERS OVER THE REGION. SNOW LEVELS
SITTING AROUND 3500 TO 4000 FEET ON SAT...WITH SOME NEW SNOW EXPECTED
OVER THE CASCADES. NOT A LOT...BUT COULD SEE 3 TO 8 INCHES OF NEW
SNOW AT THE PASSES AND ABOVE. RATHER PROGRESSIVE PATTERN OVER THE
PAC...WITH ANOTHER FRONT ARRIVING ON SUN. HAVE INCREASES PROB OF RAIN
ON SUNDAY. BRIEF BREAK ON MON...BUT LOOKS WET AFTERWARDS AS YET
ANOTHER FRONT ARRIVES ON TUE. REST OF NEXT WEEK LOOKS RATHER CLOUDY
AND WET...WITH SNOW LEVELS BOUNCING FROM 3500 TO 5500 FT. ROCKEY.
&&
.AVIATION...MOST AREAS VFR THIS MORNING. ALTHOUGH THERE ARE
POCKETS OF IFR CIGS IN THE SOUTH WILLAMETTE VALLEY NEAR KEUG AND
KCVO. A WEAK FRONT IS BRINGING RAIN...MVFR AND GUSTY SOUTH WINDS
UP TO 25 KT TO THE COAST THIS MORNING. THE FRONT WILL WEAKEN AS IT
MOVES INLAND BUT WILL LIKELY PRODUCE MVFR CONDITIONS FOR THE COAST
RANGE AND AREAS NORTH OF PORTLAND THIS AFTERNOON AND EVENING. MAY
SEE BRIEF PERIODIC MVFR CIGS BETWEEN SALEM AND PORTLAND...BUT
THINK VFR WILL GENERALLY DOMINATE SOUTH OF PORTLAND EAST OF THE
COAST RANGE. EXPECT MVFR VSBYS FOR THE COAST AND PARTS OF THE
WILLAMETTE VALLEY OVERNIGHT TONIGHT. A WARM FRONT WILL CONTINUE
THE CHANCE FOR MVFR CONDITIONS THURSDAY MORNING.
KPDX AND APPROACHES...VFR NEXT 24 HRS. THERE MAY BE BRIEF MVFR
CONDITIONS AND RAIN THIS AFTERNOON AND EVENING AS A WEAK FRONT
MOVES ACROSS THE AREA. CLOUDY WITH VFR CIGS AND VSBYS TONIGHT. TJ
&&
.MARINE...BUOY 89 AND BUOY 50 ARE SHOWING MARGINAL SMALL CRAFT
GUSTS THIS MORNING AND THE FORECAST CONFIDENCE FOR A LOW-END
SMALL CRAFT ADVISORY FOR TODAY HAS IMPROVED. THE SEAS AT THE BUOYS
ARE 1 TO 2 FT BELOW GUIDANCE THIS MORNING AND HAVE ADJUSTED TODAYS
SWELL FORECAST ACCORDINGLY. THE SEAS STILL LOOK ON TRACK TO BUILD
TO 10 FT OVERNIGHT TONIGHT AND TO ABOVE 10 FT THURSDAY...AS A
LONGER-PERIOD NW SWELL MOVES THROUGH THE WATERS. THERE IS ANOTHER
CHANCE FOR SMALL CRAFT ADVISORY WINDS THURSDAY AFTERNOON AND
EVENING. A COMPLEX LOW OFFSHORE WILL RESULT IN ELEVATED SEAS
THROUGH THE WEEKEND. TJ
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 4 PM PST THIS AFTERNOON
FOR WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT TO 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 10 PM THIS EVENING
TO 4 PM PST FRIDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA
TO FLORENCE OR OUT 60 NM.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
Area Forecast Discussion
National Weather Service Spokane WA
443 AM PST WED FEB 10 2016
.SYNOPSIS... Strong high pressure will persist today, with dry and
mild conditions however there will be increased cloud cover compared
to the last couple days. A more progressive and unsettled pattern
will return later this week, bringing a chance of light rain
Thursday in the Cascades, then throughout the region Friday
into early next week.
&&
.DISCUSSION...
Today and tonight...The unusually strong ridge which has
blanketed the Inland Northwest for the past several days will
finally begin to weaken as minor upper level disturbances track
through the region. Looking at the latest satellite loops, the
first disturbance is currently tracking through the eastern third
of Washington right now, with another one moving into western
Washington. Based on GOES BUFR sounding and radar data, both are
rather minor features. The easternmost feature only contains high
clouds, while the western one is producing a few sprinkles near
the coast. This second feature is expected to move into the
Cascades later today and could produce some very light
precipitation mainly near the crest. Otherwise the main impact of
these systems will be an increased cloud trend compared to the
last couple days as well as slightly cooler temperatures.
Nonetheless, readings will still remain warmer than normal for
this time of year with highs generally in the mid 40s to mid 50s
for most valley locations. The exception once again will occur
over the far NW part of the forecast area, namely the Methow
Valley and Okanogan Valley and Highlands due to a very stubborn
cold pool near the ground. Looks like this could stick around
until we get a more robust front through the area, which won`t
likely be today. The other problem for today will be the potential
for fog. We suspect the coverage should be greater than we have
seen for the past couple days as the wind fields are generally
lighter with higher humidity levels. Hard to tell where most of it
will form, however the HRRR suggests most of it will occur over
the western Columbia Basin. This is not supported at this time by
the fog product but will bear watching. Meanwhile for the first
time this week, visibility restrictions were developing over parts
of the Spokane/CdA area and suspect the trend will be for
increasing fog. For tonight, the second front will receive a
little boost in strength as a shortwave trough currently around
127w moves inland. We don`t think this will produce much weather
other than a chance of light precipitation again near the
Cascades. The increased cloud cover should minimize the fog
potential overnight.
For Thursday and Thursday night...the ridge looks like it could
rebound again as pressure falls develop around 140w. The
interesting thing from this development is it takes the residual
moisture from tonight`s front and pivots it from a north-south
orientation to more of an east-west orientation as a warm front
pushes northward. The isentropic ascent from this front begins to
steepen and precipitation chances will increase steadily from
Thursday afternoon into Thursday night. Light to moderate
precipitation is expected to develop with a few locations near the
Cascades nearing up to half an inch. The remainder of the area
will see amounts generally ranging from .10-.25 inches. While most
of this will fall as rain with snow rising to 5500 feet near the
Canadian Border and to 7000 feet or higher south of I-90, there
is the possibility of a messy mix across the upper Methow Valley.
Model BUFR soundings are showing a temperature right around
freezing near the ground and extending up to nearly 5000 feet
through much of the event. Strangely the NAM BUFR is showing an
initial precip type of rain by midday Thursday followed by snow.
Given the warm air advection associated with the warm front and
little potential for wet bulb cooling, this seems unlikely.
However this will need to be watched especially if the
precipitation begins earlier and falls into an initially cooler
air mass. fx
Friday through Tuesday...An active weather pattern is expected
during the extended period. A cold front will track across the
Inland NW Friday into Friday night followed by cool and showery
weather on Saturday as the upper trough axis swings through. Snow
levels early on Friday start off at 6000-7000 feet before lowering
to 3000-4000 feet Saturday morning behind the cold front. Behind
the cold front mid level westerly flow will favor showers most
prevalent near the Cascade crest and Idaho Panhandle with snow
showers expected over the passes. Given the time of year (mid-
February) and its associated higher sun angle compared to late
December road temperatures may be too warm for significant travel
impacts over the passes but this will continue to be monitored.
Another warm front will pass through Sunday into Monday bringing
another round of precipitation with rising snow levels. Monday
has the potential to be very mild with the Inland NW in the warm
sector with breezy south- southwest winds as pressure gradients
tighten. The details differ after Monday with the timing of a cold
front with the ECMWF showing Monday night and GFS Tuesday night.
Given these uncertainties no changes were made to the Tuesday
forecast which favors the slower solution. This front may bring
in breezy to windy conditions once it passes. JW
&&
.AVIATION...
12Z TAFS: Fog and stratus is much more prevalent this morning than
it`s been compared to the last few days. The latest fog product was
showing widespread stratus over most of the valleys of NE WA and N
ID. Confidence is high that this will bring IFR (or worse)
conditions to GEG and COE through at least 18z. Although there
wasn`t anything evident around SFF at 12z, it could easily spread
into there later this morning resulting in IFR conditions as well.
For now we will leave it out of the forecast as the steering flow is
quite weak. Patchy fog was also reported near EAT however the local
webcams suggest it is quite patchy and mainly located by the river.
Conditions there could vary rapidly. Also some stratus forming just
east of MWH and it could approach the airport later this
morning.Odds are not high however so we left it out of the forecast.
LWS and PUW will continue to see VFR conditions due to continued
east winds. We suspect most of the low clouds will clear between 18-
20z with VFR conditions for all sites after that. Forecast
confidence for the overnight hours is low. We should see high clouds
pass over the area as a weak front passes through the region,
however whether or not this will impede the reformation of stratus
or fog is questionable. We suspect it won`t and placed IFR/MVFR
conditions back into the forecast between 06-09z for most sites. fx
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 46 34 46 38 48 36 / 0 0 30 40 60 70
Coeur d`Alene 46 34 46 37 47 37 / 0 0 20 50 60 80
Pullman 51 39 51 40 52 38 / 0 0 10 20 50 60
Lewiston 55 40 56 42 57 42 / 0 0 0 10 40 50
Colville 42 32 41 35 42 36 / 0 10 50 70 60 70
Sandpoint 42 33 43 35 44 34 / 0 10 30 70 60 90
Kellogg 43 35 44 38 44 36 / 0 0 20 50 50 90
Moses Lake 47 34 47 38 48 37 / 0 0 30 30 50 40
Wenatchee 42 33 40 35 45 35 / 0 0 50 70 50 30
Omak 36 31 37 34 38 34 / 0 0 50 70 50 40
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Air Stagnation Advisory until 10 AM PST Saturday for East Slopes
Northern Cascades-Moses Lake Area-Northeast Mountains-
Okanogan Highlands-Okanogan Valley-Upper Columbia Basin-
Waterville Plateau-Wenatchee Area.
&&
$$
AREA FORECAST DISCUSSION
NWS PORTLAND OR
247 AM PST WED FEB 10 2016
.SYNOPSIS...MILD AIR MASS TO REMAIN OVER THE REGION THROUGH FRI.
WEAK FRONTS OFFSHORE WILL BRUSH THE NW TODAY AND THU...WITH VARIABLE
CLOUDINESS ACROSS THE REGION...ALONG WITH SOME SPOTTY LIGHT RAIN
ALONG THE COAST AND POSSIBLY INLAND. THAT CHANGES BY FRI...AS FIRST
IN A SERIES OF FRONTS PUSH INTO THE PAC NW. SHOWERY ON SATURDAY...BUT
MORE RAIN ARRIVES ON SUNDAY.
&&
.SHORT TERM...TODAY THROUGH FRIDAY...
UPPER RIDGE OVER THE PAC NW WILL SLOWLY SHIFT EASTWARD TODAY AND THU.
THAT MEANS MILD SOUTHWEST FLOW WILL TAKE HOLD OVER THE REGION. AT
SAME TIME...SEVERAL WEAKENING FRONTS WILL APPROACH FROM THE WEST.
WHILE MOST OF THE PRECIPITATION WILL REMAIN OFFSHORE...WILL SEE
CONSIDERABLY MORE IN WAY OF CLOUDS ACROSS THE REGION TODAY THROUGH
THU.
REMAINS OF THE FIRST FRONT SITS JUST OFFSHORE THIS AM...AND WILL MOVE
INLAND TODAY. NOT MUCH IN WAY OF RAIN...BUT SHOULD SEE SPOTTY LIGHT
RAIN ON THE COAST WITH ONLY LIGHT RAINFALL AMOUNTS. FURTHER
INLAND...SHOULD JUST SEE OCCASIONAL SPRINKLES OR POSSIBLY A BRIEF
LIGHT SHOWER. OVERALL...DRY INLAND TODAY AND TONIGHT. MODELS
CONTINUE TO DEPICT THIS WEAK BOUNDARY LIFTING BACK TO THE N AS A WARM
FRONT ON THU. AGAIN...NOT A LOT OF PRECIPITATION BUT ENOUGH FOR
SPOTTY LIGHT RAIN...MAINLY ALONG THE COAST AND INTO SW WASHINGTON.
WITH LACK OF ANY AIR MASS CHANGE...AND WEAK WINDS OVER REGION... THE
MILD TEMPERATURE WILL CONTINUE. NORMALS HIGHS FOR THIS TIME OF FEB
ARE GENERALLY IN THE LOWER 50S. SO...WILL KEEP FORECAST HIGHS FOR
NEXT FEW DAYS IN THE MID TO UPPER 50S.
FOR PAST MANY DAYS...MODELS HAVE BEEN INDICATING FIRST DECENT SHOT OF
RAIN WOULD PUSH INTO THE REGION ON FRI AS A MODERATELY STRONG COLD
FRONT ARRIVES. NO CHANGES TO THAT THOUGHT TRAIN. WILL KEEP RAIN IN
FORECAST ON FRI...WITH 0.50 TO 1.00 INCH OVER COAST RANGE AND S WASH
CASCADES...WITH 0.25 TO 0.50 INCH ELSEWHERE. SNOW LEVELS REMAIN
ABOVE 8000 FT THROUGH FRI AFTERNOON...THEN WILL LOWER TO 3500 TO 4000
FT BY LATE FRI NIGHT. ROCKEY.
.LONG TERM...SATURDAY THROUGH TUESDAY...
COOLER ON SATURDAY...WITH SHOWERS OVER THE REGION. SNOW LEVELS
SITTING AROUND 3500 TO 4000 FEET ON SAT...WITH SOME NEW SNOW EXPECTED
OVER THE CASCADES. NOT A LOT...BUT COULD SEE 3 TO 8 INCHES OF NEW
SNOW AT THE PASSES AND ABOVE. RATHER PROGRESSIVE PATTERN OVER THE
PAC...WITH ANOTHER FRONT ARRIVING ON SUN. HAVE INCREASES PROB OF RAIN
ON SUNDAY. BRIEF BREAK ON MON...BUT LOOKS WET AFTERWARDS AS YET
ANOTHER FRONT ARRIVES ON TUE. REST OF NEXT WEEK LOOKS RATHER CLOUDY
AND WET...WITH SNOW LEVELS BOUNCING FROM 3500 TO 5500 FT. ROCKEY.
&&
.AVIATION...VFR MOST AREAS ALTHOUGH THERE MAY BE SOME PATCHY
VALLEY FOG UNDER THE HIGH OVERCAST. AT THIS TIME...NOTHING IS AT
THE TAF TERMINALS AND KUAO IS THE ONLY SITE SHOWING ANY VISIBILITY
REDUCTION. KEUG BRIEFLY FOGGED IN EARLIER BUT INCREASING
SOUTHEASTERLY WINDS HAVE SCOURED IT OUT. OTHERWISE...EXPECT VFR
CONDS THROUGH 11/12Z. A WEAK FRONT BRUSHES THE COAST THIS
AFTERNOON AND MAY BRING HIGHER END MVFR CIGS TO THE COASTAL
TERMINALS. NOT MUCH IMPACT EXPECTED INLAND ASIDE FROM VERY LIGHT
RAIN POSSIBLE 16Z-03Z AS CONDS LIKELY REMAIN VFR.
KPDX AND APPROACHES...VFR NEXT 24 HRS. MAY GET SOME PERIODS OF
HIGHER TERRAIN OBSCURATION OVER THE CASCADES AS WEAK RAIN BANDS
CROSS THE AREA 20Z-03Z. /JBONK
&&
.MARINE...A DECAYING FRONT WILL CROSS THE WATERS TODAY ALTHOUGH
CONFIDENCE IS BELOW NORMAL WITH REGARD TO THE WIND STRENGTH. WIND
SPEEDS ARE CURRENTLY BEING OVERDONE BY MODELS BY A FEW KTS. ALSO
SHORTENED THE TIME OF THE SCA FOR WINDS BY SEVERAL HOURS BUT EVEN
WITH THE WEAKER WINDS, IT APPEARS THERE WILL STILL BE ENOUGH WIND
TO JUSTIFY THE SCA FOR A SEVERAL HOUR PERIOD OF FREQUENT 21-25 KT
GUSTS. SEAS WILL REMAIN BELOW CRITERIA DURING THE INITIAL EVENT
BUT BECOME SOMEWHAT STEEP REACHING 7-9 FT AT 11-13 SEC.
THE LARGE AND COMPLEX PARENT LOW CENTERED OVER THE GULF OF ALASKA
WELL OFFSHORE WILL SWING THE NEXT FRONT ACROSS THE WATERS
THURSDAY AND ANOTHER ON SATURDAY NIGHT/SUNDAY. THE THURSDAY SYSTEM
IS TRENDING WEAKER OVER THE LAST 24 HOURS BUT DOES STILL APPEAR TO
BE STRONGER THEN THE IMPENDING QUESTIONABLE FRONT. SUNDAY`S WOULD
BE THE STRONGEST ASSUMING MODELS SETTLE IN ON A COMMON SOLUTION.
REGARDLESS...THE SET OF EMBEDDED LOWS INSIDE THE PARENT LOW IS
GENERATING NUMEROUS SETS OF SWELL TRAINS. THE LEADING EDGE OF
SIGNIFICANT SEAS WILL REACH THE OUTER WATERS AROUND MIDNIGHT
TONIGHT. SEAS WILL POSSIBLY STAY 10-15 FEET AND BECOME CONFUSED AT
TIMES THROUGH AT LEAST SUNDAY. DECIDED TO ONLY ISSUE A SCA FOR
SEAS THROUGH FRIDAY DAYLIGHT WITH CONFIDENCE BECOMING LIMITED
THEREAFTER GIVEN THE TIME RANGE. /JBONK
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FOR T0DAY ON ALL WATERS.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS ON ALL WATERS
TODAY THROUGH FRI.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
Area Forecast Discussion
National Weather Service Spokane WA
303 AM PST WED FEB 10 2016
.SYNOPSIS...
Strong high pressure will persist into Wednesday, with dry and
mild conditions. A more progressive and unsettled pattern will
return late this week, bringing a chance of light rain Thursday in
the Cascades, then throughout the region Friday into the weekend.
&&
.DISCUSSION...
Today and tonight...The unusually strong ridge which has
blanketed the Inland Northwest for the past several days will
finally begin to weaken as minor upper level disturbances track
through the region. Looking at the latest satellite loops, the
first disturbance is currently tracking through the eastern third
of Washington right now, with another one moving into western
Washington. Based on GOES BUFR sounding and radar data, both are
rather minor features. The easternmost feature only contains high
clouds, while the western one is producing a few sprinkles near
the coast. This second feature is expected to move into the
Cascades later today and could produce some very light
precipitation mainly near the crest. Otherwise the main impact of
these systems will be an increased cloud trend compared to the
last couple days as well as slightly cooler temperatures.
Nonetheless, readings will still remain warmer than normal for
this time of year with highs generally in the mid 40s to mid 50s
for most valley locations. The exception once again will occur
over the far NW part of the forecast area, namely the Methow
Valley and Okanogan Valley and Highlands due to a very stubborn
cold pool near the ground. Looks like this could stick around
until we get a more robust front through the area, which won`t
likely be today. The other problem for today will be the potential
for fog. We suspect the coverage should be greater than we have
seen for the past couple days as the wind fields are generally
lighter with higher humidity levels. Hard to tell where most of it
will form, however the HRRR suggests most of it will occur over
the western Columbia Basin. This is not supported at this time by
the fog product but will bear watching. Meanwhile for the first
time this week, visibility restrictions were developing over parts
of the Spokane/CdA area and suspect the trend will be for
increasing fog. For tonight, the second front will receive a
little boost in strength as a shortwave trough currently around
127w moves inland. We don`t think this will produce much weather
other than a chance of light precipitation again near the
Cascades. The increased cloud cover should minimize the fog
potential overnight.
For Thursday and Thursday night...the ridge looks like it could
rebound again as pressure falls develop around 140w. The
interesting thing from this development is it takes the residual
moisture from tonight`s front and pivots it from a north-south
orientation to more of an east-west orientation as a warm front
pushes northward. The isentropic ascent from this front begins to
steepen and precipitation chances will increase steadily from
Thursday afternoon into Thursday night. Light to moderate
precipitation is expected to develop with a few locations near the
Cascades nearing up to half an inch. The remainder of the area
will see amounts generally ranging from .10-.25 inches. While most
of this will fall as rain with snow rising to 5500 feet near the
Canadian Border and to 7000 feet or higher south of I-90, there
is the possibility of a messy mix across the upper Methow Valley.
Model BUFR soundings are showing a temperature right around
freezing near the ground and extending up to nearly 5000 feet
through much of the event. Strangely the NAM BUFR is showing an
initial precip type of rain by midday Thursday followed by snow.
Given the warm air advection associated with the warm front and
little potential for wet bulb cooling, this seems unlikely.
However this will need to be watched especially if the
precipitation begins earlier and falls into an initially cooler
air mass. fx
Friday through Tuesday...An active weather pattern is expected
during the extended period. A cold front will track across the
Inland NW Friday into Friday night followed by cool and showery
weather on Saturday as the upper trough axis swings through. Snow
levels early on Friday start off at 6000-7000 feet before lowering
to 3000-4000 feet Saturday morning behind the cold front. Behind
the cold front mid level westerly flow will favor showers most
prevalent near the Cascade crest and Idaho Panhandle with snow
showers expected over the passes. Given the time of year (mid-
February) and its associated higher sun angle compared to late
December road temperatures may be too warm for significant travel
impacts over the passes but this will continue to be monitored.
Another warm front will pass through Sunday into Monday bringing
another round of precipitation with rising snow levels. Monday
has the potential to be very mild with the Inland NW in the warm
sector with breezy south- southwest winds as pressure gradients
tighten. The details differ after Monday with the timing of a cold
front with the ECMWF showing Monday night and GFS Tuesday night.
Given these uncertainties no changes were made to the Tuesday
forecast which favors the slower solution. This front may bring
in breezy to windy conditions once it passes. JW
&&
.AVIATION...
06Z TAFS: Fog and stratus was observed for most of the mountain
valleys this morning and along the Spokane/Columbia
rivers...closer to water sources. The inversion will remain strong
again tonight and fog/stratus will likely form in those areas
again tonight. However the strong ridge of high pressure that has
been over the region will shift east and bend slightly overnight.
This will allow upper level clouds to move into the region
overnight as well...and this may mitigate somewhat the strong
radiational cooling. In addition the surface flow will gradually
come around to southerly through the evening and this should pile
up the moisture for the northern valleys. With the exception of
the eastern basin and the Palouse at least some fog and stratus
will be possible for the TAF sites. So KLWS/KPUW can expect VFR
conditions through 00z. At the other TAF sites current VFR
conditions will likely drop down to MVFR cigs/vsby between 12-18z
then bounce back to VFR with a thickening but high cloud deck.
Tobin
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 46 34 46 38 48 36 / 0 0 30 40 60 70
Coeur d`Alene 46 34 46 37 47 37 / 0 0 20 50 60 80
Pullman 51 39 51 40 52 38 / 0 0 10 20 50 60
Lewiston 55 40 56 42 57 42 / 0 0 0 10 40 50
Colville 42 32 41 35 42 36 / 0 10 50 70 60 70
Sandpoint 42 33 43 35 44 34 / 0 10 30 70 60 90
Kellogg 43 35 44 38 44 36 / 0 0 20 50 50 90
Moses Lake 47 34 47 38 48 37 / 0 0 30 30 50 40
Wenatchee 42 33 40 35 45 35 / 0 0 50 70 50 30
Omak 36 31 37 34 38 34 / 0 0 50 70 50 40
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Air Stagnation Advisory until 10 AM PST Saturday for East Slopes
Northern Cascades-Moses Lake Area-Northeast Mountains-
Okanogan Highlands-Okanogan Valley-Upper Columbia Basin-
Waterville Plateau-Wenatchee Area.
&&
$$
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1028 AM CST WED FEB 10 2016
.UPDATE...
LITTLE CHANGE FROM THE PREVIOUS FORECAST. CLOUDS REMAIN THE
BIGGEST CHALLENGE. NONE OF THE SHORT TERM GUIDANCE HAS GRABBED ON
TO THE TENDRIL OF LOW LEVEL CLOUDS CURRENTLY EXTENDING INTO
SOUTHERN WISCONSIN FROM THE NORTH. MODEL SOUNDINGS ARE SHOWING AT
LEAST SCATTERED THROUGH THE AFTERNOON IN OUR SOUTHEAST. THE REST
OF THE FORECAST AREA SHOULD REMAIN FAIRLY CLEAR...THOUGH OUR FAR
SOUTHWEST MAY SEE SOME MID CLOUDS EXTENDING FROM A LOW PRESSURE
SYSTEM PASSING THROUGH THE GREAT PLAINS INTO THE LOWER MISSISSIPPI
VALLEY.
&&
.AVIATION/18Z TAFS/...
SHORT TERM GUIDANCE IS STILL STRUGGLING TO RESOLVE THE BAND OF
VFR/MVFR CLOUDS EXTENDING INTO THE SOUTHERN WISCONSIN FROM THE
NORTH. PER MODEL SOUNDINGS...EXPECTING CIGS TO HOVER AROUND THAT
3KFT LEVEL THROUGH THE DAY...SKEWING TOWARD JUST ABOVE 3KFT AS THE
DAY GOES ON. CLOUDS SHOULD DIMINISH THIS EVENING AND SKIES SHOULD
REMAIN MOSTLY CLEAR THROUGH THURSDAY. WINDS WILL BE GUSTY ALONG
THE LAKE BEFORE TAPERING OFF AFTER SUNSET.
&&
.PREV DISCUSSION... /ISSUED 308 AM CST WED FEB 10 2016/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.
THE MAIN FOCUS IS ON CLOUD COVER WITH WHETHER IT WILL CLEAR OUT
AND IF SO...HOW FAST.
CURRENTLY...NORTHWESTERLY FLOW IS IN PLACE ACROSS THE UPPER MIDWEST
FROM THE SURFACE ON UP THROUGH THE UPPER ATMOSPHERE DUE TO A STACKED
TROUGH ENTERING NEW ENGLAND. NOT MUCH WILL CHANGE WITH THIS PATTERN
LOCALLY TODAY WITH A RIDGE AXIS PLACED ALONG THE UPPER MISSISSIPPI
RIVER VALLEY AND A QUICK MOVING LOW PRESSURE SYSTEM DROPPING THROUGH
THE DAKOTAS/CENTRAL PLAINS. THE FLOW ALOFT WILL REMAIN RELATIVELY
UNCHANGED AS WELL WITH 850MB TEMPERATURES HANGING AROUND -20C. IR
SATELLITE SHOWS A BAND OF CLOUDS OVER CENTRAL WISCONSIN EXTENDING UP
TO LAKE SUPERIOR WITH A CLEAR SLOT ALONG LAKE MICHIGAN. NONE OF THE
SHORT TERM MODELS SEEM TO HAVE A GOOD HANDLE ON THIS THIN LAYER OF
MOISTURE AROUND 3KFT WITH THE 10.06Z RAP THE CLOSEST WHEN COMPARED
TO THE HRRR/WRF-ARW/NMM. WITH THE NORTHWEST LOW LEVEL FLOW...AM
EXPECTING THAT SOME OF THIS LOW LEVEL MOISTURE OF OF THE LAKE WILL
HELP TO KEEP SOME SORT OF CLOUD COVER AROUND TODAY UNTIL THE LOW
LEVEL WINDS TURN MORE WESTERLY TONIGHT.
THURSDAY - CONFIDENCE...MEDIUM
ELONGATED SHEAR AXIS ON WESTERN PERIPHERY OF 500 MILLIBAR TROUGH
WILL SHIFT EAST WITH STRONG NW UPPER FLOW PERSISTING. VERY CHILLY
AIRMASS REMAINS IN PLACE WITH 925 TEMPS SHOWING ONLY SUBTLE
MODIFICATION AS LOW LEVEL WIND FIELD TURNS MORE WESTERLY. SURFACE
HIGH SHIFTS FROM MN INTO IA AND IL.
FRIDAY AND FRIDAY NIGHT - CONFIDENCE...MEDIUM
NORTHWEST 500 MILLIBAR FLOW STRENGTHENS AND BECOMES INCREASINGLY
CYCLONIC ACROSS THE GREAT LAKES REGION. EMBEDDED SHORTWAVE WITHIN
THIS FLOW HEADS SOUTHEAST INTO LWR MI WITH CYCLOGENESIS ACROSS THE
EASTERN GRT LAKES REGION. THIS WILL DRAG A COLD FRONT THROUGH SRN
WI. 925 TEMPS WILL DROP THROUGH THE NEGATIVE TEENS CELSIUS WITH
NEGATIVE LOW AND EVEN POSSIBLE MID 20S CELSIUS INTO FRIDAY NIGHT.
THIS WILL LEAD TO A BITTERLY COLD AIRMASS WITH WIND CHILLS GETTING
NEAR OR IN SOME CASES REACHING ADVISORY CRITERIA. SOME UNCERTAINTY
ON WIND STRENGTH LATER FRIDAY NIGHT WITH THE ECMWF SHOWING A
WEAKER GRADIENT SETTING UP WITH 1040 MILLIBAR HIGH DRAWING CLOSER
FROM MN AND IA. THE NAM AND GFS SUGGEST A LITTLE MORE WIND
POTENTIAL.
SATURDAY - CONFIDENCE...MEDIUM
AFTER A BITTERLY COLD START 1045 MILLIBAR HIGH AND SUBSIDING
INFLUENCE SHOULD RESULT IN A DECENT AMOUNT OF SUNSHINE. MID LEVEL
FLOW REMAINS STRONG FROM THE NORTHWEST THOUGH TRENDING MORE
ANTICYCLONIC. CORE OF LOW LEVEL THERMAL TROUGH REMAINS ACROSS SRN
WI WITH 925 TEMPS AOB -20C IN THE MORNING MODIFYING ONLY INTO THE
UPPER TEENS CELSIUS DURING THE AFTERNOON. SO THE CHILLY SUPERBLEND
GUID SHOWING MANY HIGHS STRUGGLING TO GET OUT OF THE SINGLE DIGITS
SEEMS REASONABLE.
SUNDAY AND SUNDAY NIGHT - CONFIDENCE...LOW TO MEDIUM
WHILE MID LEVEL RIDGING AND LINGERING INFLUENCE OF LOW LEVEL
RIDGE AXIS WILL DOMINATE AT THE OUTSET...MODELS ARE ALL SHOWING A
SHORTWAVE TROUGH HEADING EAST FROM DAKOTAS/MN AND IA THROUGHOUT
THE DAY AND INTO THE OVERNIGHT HOURS. WAA REGIME SETS UP INITIALLY
WITH THE ECMWF SHOWING LESS PRODUCTIVE QPF THAN THE GFS. 850
TROUGH SWINGS THROUGH SUNDAY NIGHT WITH ADDITIONAL SNOW CHANCES.
BEST DCVA PROGGD TO ARRIVE LATER IN THE AFTN INTO THE ERLY EVE
HRS.
MONDAY - CONFIDENCE...MEDIUM
LOW LEVEL TROUGH SHIFTS EAST THOUGH STILL LINGERING MID LEVEL
CYCLONIC FLOW. SO SMALL SUPERBLEND POPS CONTINUE.
TUESDAY - CONFIDENCE...LOW
ANOTHER SYSTEM IS EXPECTED TO RIDE IN FROM THE NORTHWEST. SOME
PRETTY BIG TIMING DIFFERENCES. GFS BRINGS THIS SYSTEM IN MUCH
QUICKER DURING THE DAY WHILE THE ECMWF HOLDS PRECIP OFF UNTIL
TUESDAY NIGHT. FOR NOW WENT WITH THE SUPERBLEND POPS....WHICH FAR
NOW ANYWAYS...FAVORS THE QUICKER GFS SOLUTION.
AVIATION/12Z TAFS/...LOW END VFR/HIGH END MVFR CEILINGS ARE IN
PLACE FOR MUCH OF CENTRAL WISCONSIN WITH CLEAR SKIES ON BOTH SIDES
OF IT. EXPECTING THAT CONDITIONS WILL MAINLY BE VFR BUT THERE COULD
BE SOME BRIEF DROPS TO MVFR...PARTICULARLY AT MSN WHERE THE BAND
IS CURRENTLY SET UP. WINDS WILL GRADUALLY DECREASE THROUGH THE
EVENING AND TURN WESTERLY OVERNIGHT.
MARINE...OFFSHORE WINDS WILL CONTINUE INTO TONIGHT WITH WINDS
GRADUALLY DIMINISHING AND TURNING TO THE WEST TOWARD TOMORROW MORNING.
SMALL CRAFT ADVISORY CONDITIONS WILL CONTINUE THROUGH AT LEAST
MIDNIGHT...POSSIBLY A BIT LONGER IF THE WAVES STAY UP IN THE 3-5
FT RANGE TOWARD THE OPEN WATERS.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR LMZ643>646.
&&
$$
UPDATE...BSH
TODAY/TONIGHT AND AVIATION/MARINE...HALBACH
THURSDAY THROUGH TUESDAY...COLLAR
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
308 AM CST WED FEB 10 2016
.TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.
THE MAIN FOCUS IS ON CLOUD COVER WITH WHETHER IT WILL CLEAR OUT
AND IF SO...HOW FAST.
CURRENTLY...NORTHWESTERLY FLOW IS IN PLACE ACROSS THE UPPER MIDWEST
FROM THE SURFACE ON UP THROUGH THE UPPER ATMOSPHERE DUE TO A STACKED
TROUGH ENTERING NEW ENGLAND. NOT MUCH WILL CHANGE WITH THIS PATTERN
LOCALLY TODAY WITH A RIDGE AXIS PLACED ALONG THE UPPER MISSISSIPPI
RIVER VALLEY AND A QUICK MOVING LOW PRESSURE SYSTEM DROPPING THROUGH
THE DAKOTAS/CENTRAL PLAINS. THE FLOW ALOFT WILL REMAIN RELATIVELY
UNCHANGED AS WELL WITH 850MB TEMPERATURES HANGING AROUND -20C. IR
SATELLITE SHOWS A BAND OF CLOUDS OVER CENTRAL WISCONSIN EXTENDING UP
TO LAKE SUPERIOR WITH A CLEAR SLOT ALONG LAKE MICHIGAN. NONE OF THE
SHORT TERM MODELS SEEM TO HAVE A GOOD HANDLE ON THIS THIN LAYER OF
MOISTURE AROUND 3KFT WITH THE 10.06Z RAP THE CLOSEST WHEN COMPARED
TO THE HRRR/WRF-ARW/NMM. WITH THE NORTHWEST LOW LEVEL FLOW...AM
EXPECTING THAT SOME OF THIS LOW LEVEL MOISTURE OF OF THE LAKE WILL
HELP TO KEEP SOME SORT OF CLOUD COVER AROUND TODAY UNTIL THE LOW
LEVEL WINDS TURN MORE WESTERLY TONIGHT.
.THURSDAY - CONFIDENCE...MEDIUM
ELONGATED SHEAR AXIS ON WESTERN PERIPHERY OF 500 MILLIBAR TROUGH
WILL SHIFT EAST WITH STRONG NW UPPER FLOW PERSISTING. VERY CHILLY
AIRMASS REMAINS IN PLACE WITH 925 TEMPS SHOWING ONLY SUBTLE
MODIFICATION AS LOW LEVEL WIND FIELD TURNS MORE WESTERLY. SURFACE
HIGH SHIFTS FROM MN INTO IA AND IL.
.FRIDAY AND FRIDAY NIGHT - CONFIDENCE...MEDIUM
NORTHWEST 500 MILLIBAR FLOW STRENGTHENS AND BECOMES INCREASINGLY
CYCLONIC ACROSS THE GREAT LAKES REGION. EMBEDDED SHORTWAVE WITHIN
THIS FLOW HEADS SOUTHEAST INTO LWR MI WITH CYCLOGENESIS ACROSS THE
EASTERN GRT LAKES REGION. THIS WILL DRAG A COLD FRONT THROUGH SRN
WI. 925 TEMPS WILL DROP THROUGH THE NEGATIVE TEENS CELSIUS WITH
NEGATIVE LOW AND EVEN POSSIBLE MID 20S CELSIUS INTO FRIDAY NIGHT.
THIS WILL LEAD TO A BITTERLY COLD AIRMASS WITH WIND CHILLS GETTING
NEAR OR IN SOME CASES REACHING ADVISORY CRITERIA. SOME UNCERTAINTY
ON WIND STRENGTH LATER FRIDAY NIGHT WITH THE ECMWF SHOWING A
WEAKER GRADIENT SETTING UP WITH 1040 MILLIBAR HIGH DRAWING CLOSER
FROM MN AND IA. THE NAM AND GFS SUGGEST A LITTLE MORE WIND
POTENTIAL.
.SATURDAY - CONFIDENCE...MEDIUM
AFTER A BITTERLY COLD START 1045 MILLIBAR HIGH AND SUBSIDING
INFLUENCE SHOULD RESULT IN A DECENT AMOUNT OF SUNSHINE. MID LEVEL
FLOW REMAINS STRONG FROM THE NORTHWEST THOUGH TRENDING MORE
ANTICYCLONIC. CORE OF LOW LEVEL THERMAL TROUGH REMAINS ACROSS SRN
WI WITH 925 TEMPS AOB -20C IN THE MORNING MODIFYING ONLY INTO THE
UPPER TEENS CELSIUS DURING THE AFTERNOON. SO THE CHILLY SUPERBLEND
GUID SHOWING MANY HIGHS STRUGGLING TO GET OUT OF THE SINGLE DIGITS
SEEMS REASONABLE.
.SUNDAY AND SUNDAY NIGHT - CONFIDENCE...LOW TO MEDIUM
WHILE MID LEVEL RIDGING AND LINGERING INFLUENCE OF LOW LEVEL
RIDGE AXIS WILL DOMINATE AT THE OUTSET...MODELS ARE ALL SHOWING A
SHORTWAVE TROUGH HEADING EAST FROM DAKOTAS/MN AND IA THROUGHOUT
THE DAY AND INTO THE OVERNIGHT HOURS. WAA REGIME SETS UP INITIALLY
WITH THE ECMWF SHOWING LESS PRODUCTIVE QPF THAN THE GFS. 850
TROUGH SWINGS THROUGH SUNDAY NIGHT WITH ADDITIONAL SNOW CHANCES.
BEST DCVA PROGGD TO ARRIVE LATER IN THE AFTN INTO THE ERLY EVE
HRS.
.MONDAY - CONFIDENCE...MEDIUM
LOW LEVEL TROUGH SHIFTS EAST THOUGH STILL LINGERING MID LEVEL
CYCLONIC FLOW. SO SMALL SUPERBLEND POPS CONTINUE.
.TUESDAY - CONFIDENCE...LOW
ANOTHER SYSTEM IS EXPECTED TO RIDE IN FROM THE NORTHWEST. SOME
PRETTY BIG TIMING DIFFERENCES. GFS BRINGS THIS SYSTEM IN MUCH
QUICKER DURING THE DAY WHILE THE ECMWF HOLDS PRECIP OFF UNTIL
TUESDAY NIGHT. FOR NOW WENT WITH THE SUPERBLEND POPS....WHICH FAR
NOW ANYWAYS...FAVORS THE QUICKER GFS SOLUTION.
&&
.AVIATION/12Z TAFS/...LOW END VFR/HIGH END MVFR CEILINGS ARE IN
PLACE FOR MUCH OF CENTRAL WISCONSIN WITH CLEAR SKIES ON BOTH SIDES
OF IT. EXPECTING THAT CONDITIONS WILL MAINLY BE VFR BUT THERE COULD
BE SOME BRIEF DROPS TO MVFR...PARTICULARLY AT MSN WHERE THE BAND
IS CURRENTLY SET UP. WINDS WILL GRADUALLY DECREASE THROUGH THE
EVENING AND TURN WESTERLY OVERNIGHT.
&&
.MARINE...OFFSHORE WINDS WILL CONTINUE INTO TONIGHT WITH WINDS
GRADUALLY DIMINISHING AND TURNING TO THE WEST TOWARD TOMORROW MORNING.
SMALL CRAFT ADVISORY CONDITIONS WILL CONTINUE THROUGH AT LEAST
MIDNIGHT...POSSIBLY A BIT LONGER IF THE WAVES STAY UP IN THE 3-5
FT RANGE TOWARD THE OPEN WATERS.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR LMZ643>646.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...HALBACH
THURSDAY THROUGH TUESDAY...COLLAR
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1134 PM CST THU FEB 11 2016
.UPDATE...
ISSUED AT 908 PM CST THU FEB 11 2016
Light snow is just now beginning to move into western parts of
central Illinois, even though radar indicates it should already
be occurring. Observations show very few lower clouds so if any
light snow is occurring out there, it is flurries and the
observational sites are not picking it up yet. Still thinking that
some light snow will occur in the southwestern parts of the CWA
overnight, so believe current forecast still looks good for the
remainder of the night. May make some tweaks to overnight low
temps in the southeast, but remainder of the area, current
forecast looks fine. Update out shortly.
&&
.SHORT TERM...(Tonight)
ISSUED AT 323 PM CST THU FEB 11 2016
A fast moving clipper will produce light snow starting this evening
across western Illinois, with most of the focused lift overnight
primarily remaining across our southwestern counties. The general
trend in the 12z models has been to focus the better chances of
measurable snowfall over our southwestern and southern counties.
Have increased PoPs to likely in a narrow corridor southwest of a
line from Jacksonville to Effingham, progressing from SW to SE with
time overnight. The HRRR is the farthest southwest with the latest
updated path of forcing for precip, with the NAM80, Canadian GEM,
and ECMWF still extending at least some snow accumulation across all
of our CWA except the far NE counties NE of CMI. The NAM12 is
similar to the HRRR in limiting snow to the SW half of our CWA. Have
reduced the PoPs in our N and NE counties, north of I-74, to slight
chance. Chance PoPs were limited to generally south of a line from
Galesburg to Lincoln to Paris. Snow amounts from Jacksonville to
Effingham could reach between a half inch and one inch, with a
dusting to a half inch as far north as Rushville to Lincoln to
Decatur. South to southwest winds should remain less than 10 mph
during the snowfall, so drifting should not be a big problem
overnight.
Low temps tonight will generally settle out in the mid-teens, as
cloud cover limits the diurnal swing to only around a 10 degree drop-
off.
.LONG TERM...(Friday through Thursday)
ISSUED AT 323 PM CST THU FEB 11 2016
Friday may start out with a few lingering snow showers south of
I-70, but little additional accumulation is expected after
sunrise. The bigger story will be the arrival of very cold air on
increasing northwest winds Friday afternoon, as strong pressure
rises develop ahead of the surface high center. The tight pressure
gradient will produce wind gusts over 30 mph at times, which could
cause minor drifting of the snowfall from tonight, so slippery
travel could develop from that Friday afternoon and evening.
Wind chills late Friday night will drop very close to advisory
levels of -15F north of Peoria, with wind chills below zero in all
of our forecast area. Actual air temps will be range from zero to 8
above zero, but NW winds will remain strong enough to push wind
chills well below zero.
The next main concern will be the system for Sunday into Monday.
Model differences remain with the 12z model updates. The Canadian
GEM has started showing the splitting of energy as the trough
reaches Illinois, similar to what the ECMWF was showing yesterday.
The ECMWF has changed and now maintains the trough energy across
Illinois Sunday evening, with total QPF amounts that support snow
amounts of 1 to 2". The Canadian GEM QPF amounts support around 1
inch west of I-55, with little to no snow accum east of I-55. The
GFS remains the only model that develops a distinct surface
low/circulation that tracks across northern IL Sunday evening, with
total QPF amounts that support snowfall of 4" to 7" in our northern
counties, and 3-4" in the south. The 12z NAM now includes forecast
info through 6 pm Sunday, and is showing plenty of snow as well,
despite no surface low moving across IL. The NAM has 3-5" across our
counties for just the first 12 hours of the event through 6 pm
Sunday. We have increased PoPs into the likely category for Sunday
nearly everywhere, and likely PoPs east of I-57 Sunday night.
Our compromise forecast for QPF came out to 0.23-0.30", correlating
to snowfall amounts of 2-4", with the higher totals from Peoria and
north. There still remains quite a bit of uncertainty with how much
moisture will fall, so updates to QPF and resultant snow accums are
likely with subsequent model runs.
The accumulating snows should primarily be done by Monday morning,
but lingering light snow or flurries could continue into afternoon.
If precip does linger into the afternoon, the snow may mix
with or change to rain.
All of the extended models show a low deepening south of Illinois on
Monday, and progressing up into the Appalachian mountains Monday
night, with precip mainly southeast of our area. However, the
blended initialization kept slight chance PoPs in the eastern half
of Illinois Monday night through Tuesday night, mainly due to that
strong system.
A warming trend is indicated for next week, as upper level ridging
gradually pushes east into Illinois. We should see mid-level warming
increase enough to support high temps climbing into the upper 30s to
low 40s Tuesday and Wed, with sunshine and mid 40s to around 50 for
Thursday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Friday night)
ISSUED AT 1134 PM CST THU FEB 11 2016
Snow has not begun at any of the TAF sites yet, but with mosaic
radar loop showing most of the snow still west of the area and
nothing being reported under the higher returns on radar, thinking
is that flurries will occur at most of the TAF sites overnight,
with SPI only site getting light snow overnight for a few hours
from 07z to 09z. Vis at SPI during the light snow will be 3sm
while remainder of the time, think vis will be VFR. Do not see
cigs dropping to MVFR levels until after the snow has ended over
the area, due to very dry lower layers...seen on 00z UA sounding
and any snow currently falling is just moistening up the lower
layer. MVFR cigs at 2.5kft will occur from early morning til
afternoon in the west and later afternoon in the east. Then clouds
will scatter out and last til evening. Winds will be light out of
the southwest to start, but then become westerly and then
northwesterly for the afternoon and evening. Light wind speeds til
after winds shift to west and northwest. Then speeds increase and
become gusty with gusts of 23-38kts possible.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Auten
SHORT TERM...Shimon
LONG TERM...Shimon
AVIATION...Auten
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
316 AM EST FRI FEB 12 2016
.UPDATE...
THE LONG TERM AND AVIATION SECTIONS HAVE BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 330 PM EST THU FEB 11 2016
A COLD UPPER TROUGH OVER ONTARIO AND THE ST. LAWRENCE VALLEY WILL KEEP US
UNDER A NORTHWEST FLOW ALOFT AND TEMPERATURES COLDER THAN NORMAL THROUGH
EARLY NEXT WEEK. A CLIPPER WILL GIVE US A CHANCE OF LIGHT SNOW TOWARDS
DAYBREAK OVER WESTERN SECTIONS AND MOST AREAS FRIDAY. LAKE EFFECT
SNOW SHOWERS MAY LINGER TO MIDDAY SATURDAY ACROSS OUR NORTHEAST.
COLD HIGH PRESSURE WILL BUILD EAST ACROSS OUR REGION SATURDAY AND
SATURDAY NIGHT. AN APPROACHING AREA OF LOW PRESSURE WILL SPREAD
SNOW ACROSS OUR REGION SUNDAY INTO MONDAY. ANOTHER SYSTEM WILL
BRING A CHANCE OF SNOW MONDAY AND MONDAY NIGHT. FINALLY A FOURTH
SYSTEM WILL BRING A CHANCE OF SNOW OR MIXED PRECIPITATION AROUND THE
MIDDLE OF NEXT WEEK. TEMPERATURES WILL BETENTIALGIN TO MODERATE
TOWARDS THE MIDDLE OF NEXT WEEK AS OUR UPPER FLOW BECOMES MORE
ZONAL.
&&
.NEAR TERM.../TONIGHT AND FRIDAY/
ISSUED AT 822 PM EST THU FEB 11 2016
GOING FORECAST IS IN EXCELLENT SHAPE. FLAKES MAY FLY ACROSS PORTIONS
OF CENTRAL INDIANA BY THE MORNING RUSH. FEEL CHANCE POPS HANDLE THIS
BEST HOWEVER AS THERE IS A LOT OF NEAR SURFACE DRY AIR TO OVERCOME.
WILL HAVE TO MONITOR FOR POSSIBLE IMPACTS TO FRIDAY MORNING COMMUTE
ACROSS THE AREA...ESPECIALLY AS HRRR AND NAM PROFILES INDICATE FIRST
FLAKES MAY BEGIN REACHING THE GROUND DURING THE HEART OF THE
COMMUTE. HOWEVER...RATES APPEAR UNLIKELY TO BE SUCH THAT RAPID
ACCUMULATION WOULD OCCUR...WHICH WOULD LIMIT POTENTIAL IMPACT.
PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 330 PM EST THU FEB 11 2016
HIGH PRESSURE CENTERED OVER ILLINOIS WILL MOVE EAST ACROSS INDIANA THIS
EVENING AND ON TO THE EAST BY MONDAY. A WEAK CLIPPER OVER THE UPPER
MIDWEST AND NORTHERN PLAINS WILL MOVE TO THE MIDDLE MISSISSIPPI VALLEY
LATE TONIGHT AND ACROSS THE OHIO VALLEY FRIDAY.
MOSTLY CLEAR CONDITIONS WERE OCCURRING ACROSS WESTERN SECTIONS THIS AFTERNOON
WHILE PARTLY CLOUDY CONDITIONS WERE THE RULE IN THE EAST. MID/HIGH CLOUDS
OVER THE MIDDLE MISSISSIPPI VALLEY WILL MOVE OUR WAY AND THICKEN OVERNIGHT.
ANY SNOW FROM THE CLIPPER PROBABLY WON`T REACH OUR AREA UNTIL AFTER 09Z AND
THIS WILL BE MAINLY ACROSS WESTERN AND SOUTHWEST AREAS.
SCATTERED LIGHT SNOW SHOWERS WILL SPREAD EAST ACROSS OUR REGION FRIDAY. AMOUNTS
WILL BE GENERALLY A QUARTER INCH. BUT SOME LAKE EFFECT SNOW SHOWERS ARE POSSIBLE
ACROSS OUR NORTHEAST LATE FRIDAY AS OUR FLOW BECOMES MORE NORTHERLY AND AMOUNTS
THERE WILL BE A LITTLE HIGHER BY LATE FRIDAY.
LOWERED TEMPERATURES SLIGHTLY CENTRAL AND EAST TONIGHT AS HIGH PRESSURE WILL
PROVIDE GOOD RADIATIONAL COOLING EARLY ON. OTHERWISE...A MOS BLEND OF TEMPERATURES
SEEM REASONABLE. WINDS WILL BE LIGHT TONIGHT AND THEN BECOME NORTHWEST WITH
GUSTS UP TO 25 MPH BY FRIDAY AFTERNOON AS A PRESSURE GRADIENT STRENGTHENS.
&&
.SHORT TERM.../FRIDAY NIGHT THROUGH SUNDAY/
ISSUED AT 330 PM EST THU FEB 11 2016
WE WILL REMAIN UNDER A COLD NORTHWEST FLOW FRIDAY NIGHT SATURDAY AS HIGH
PRESSURE OVER THE NORTHERN PLAINS BUILDS OUR WAY. MODELS INDICATE SOME FETCH OFF
OF LAKE MICHIGAN WHICH WILL PRODUCE SCATTERED LAKE EFFECT SNOW SHOWERS OVER
NORTHEAST SECTIONS. WHILE COLD AND DRY WEATHER WILL BE THE RULE ELSEWHERE.
MODELS INDICATE 850 TEMPERATURES OF -15 TO -21 CELSIUS SATURDAY AND -8 TO -12
CELSIUS SUNDAY. THIS WILL TRANSLATE TO HIGHS IN THE TEENS SATURDAY 20 TO 26
DEGREES SUNDAY. LOWS WILL BE MOSTLY IN THE SINGLE DIGITS BOTH FRIDAY AND
SATURDAY NIGHT. BUT LOWS NEAR ZERO ARE POSSIBLE SATURDAY NIGHT OVER NORTHEAST
SECTIONS AS CLOUDS MAY NOT ARRIVE THERE UNTIL LATE.
THE BIGGEST CONCERN WILL BE SNOW AMOUNTS SUNDAY AS AREA OF LOW PRESSURE MOVES
INTO THE UPPER MIDWEST AND A STRONGER CLIPPER MOVES OUR WAY. THE NAM/OPERATIONAL
GFS AND THE NEW EURO ALL INDICATE AN INCH OR TWO OF SNOW BY SUNDAY AFTERNOON...
WHILE THE CANADIAN HARDLY HAS ANYTHING AS MOST OF ITS PRECIPITATION IS FARTHER
SOUTHWEST. FOR NOW WILL GO WITH A BLEND. WILL RAISE POPS TO LIKELY OVER WEST
CENTRAL AND NORTHWEST AND GO WITH HIGH CHANCE POPS ELSEWHERE BY SUNDAY AFTERNOON.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
ISSUED AT 316 AM EST FRI FEB 12 2016
A LOT OF MOVING PARTS IN REGARDS TO THE EARLY WEEK SYSTEM POISED
TO AFFECT THE EASTERN U S AND THE 00Z MODEL SUITE DID LITTLE TO
INCREASE THE LOW CONFIDENCE IN HIGHLIGHTING SPECIFIC IMPACTS TO
CENTRAL INDIANA. THE EXTENDED PERIOD WILL BE ACTIVE WITH VARIOUS
SNOW THREATS THROUGH MIDWEEK BEFORE A WARMING TREND COMMENCES FOR
THE SECOND HALF OF THE WEEK.
NORTHERN STREAM CLIPPER SYSTEM WILL SWING THROUGH THE LOWER GREAT
LAKES LATE SUNDAY AND EARLY MONDAY AND WILL PRESENT CHANCES FOR
SNOW. AT THE SAME TIME...LOW PRESSURE ORGANIZING OVER THE LOWER
MISSISSIPPI VALLEY WILL TRACK NORTHEAST INTO THE LOWER APPALACHIANS
BY TUESDAY. ADDITIONALLY...OP GFS AND ECMWF BOTH TRACK ANOTHER
CLIPPER INTO THE MID MISSISSIPPI VALLEY. THE 00Z RUNS OF THE
OPERATIONAL MODELS ARE TRACKING THE MAIN SYSTEM EAST OF THE
APPALACHIANS AND ARE SUGGESTIVE OF LESS OF AN IMPACT TO THE REGION
WITH NO PHASING WITH THE CLIPPER TO THE NORTHWEST. GFS ENSEMBLE
MEMBERS ON THE OTHER HAND ARE ALL OVER THE PLACE WITH THE SURFACE
LOW TRACK DUE TO VARYING DEGREES OF PHASING IN THE UPPER LEVELS.
FURTHER MUDDYING THE WATERS IS THE MARGINAL TEMPS IN THE NEAR
SURFACE LAYER WHICH ARGUES FOR EVEN THE POSSIBILITY FOR OTHER PRECIP
TYPES TO MIX IN WITH SNOW FOR A TIME ON MONDAY AND TUESDAY.
THE UPPER LEVEL FLOW AND TELECONNECTION PATTERN SUGGESTS
POTENTIAL IS THERE FOR SOME SHIFT NORTH AND WEST TO THE MAIN
SYSTEM. WITH THE PRIMARY UPPER WAVE STILL OUT OVER THE PACIFIC AND
NOT FULLY SAMPLED YET...FUTURE MODEL RUNS TODAY AND SATURDAY WILL
BE CRITICAL IN DETERMINING IF THE MAIN STORM SHIFTS LEFT AND
PRESENTS A GREATER IMPACT TO PARTS OF THE FORECAST AREA FOR EARLY
WEEK. AT THIS TIME HOWEVER...ATTEMPTING TO EMPLOY ANY DETAIL
INCLUDING POTENTIAL SNOWFALL AMOUNTS IS POINTLESS. WILL CARRY
CHANCES OF SNOW MONDAY AND TUESDAY WITH A POSSIBILITY FOR RAIN TO
MIX IN ACROSS THE SOUTH TUESDAY AS CRITICAL LOW LEVEL THICKNESSES
WARM.
HIGH PRESSURE WILL BRING DRIER WEATHER TO THE REGION BY
MIDWEEK...WITH EXPANDING RIDGING ALOFT AND STRONG SOUTHERLY FLOW
PROVIDING A NICE WARMUP BY THE END OF THE WEEK AS TEMPERATURES GO
ABOVE NORMAL.
&&
.AVIATION /DISCUSSION FOR THE 120900Z TAF UPDATE/...
ISSUED AT 316 AM EST FRI FEB 12 2016
LITTLE CHANGE NEEDED FOR THE EARLY MORNING UPDATE. SEEING AREA OF SNOW
SHOWERS IMPACT CENTRAL ILLINOIS AS THEY MOVE SOUTHEAST. ANY
IMPACTS AGAIN LOOK PRIMARILY FOCUSED ON THE KBMG AND KHUF
TERMINALS THROUGH MID MORNING.
06Z DISCUSSION FOLLOWS.
UPPER DISTURBANCE CURRENTLY DROPPING SOUTHEAST THROUGH NORTHERN MISSOURI
IS EXPECTED TO SETTLE INTO WESTERN KENTUCKY AROUND SUNRISE FRIDAY. COULD
BE SOME LIGHT SNOW AT THE TERMINALS ROUGHLY 121000Z-121600Z ASSOCIATED WITH
THIS FEATURE...MAINLY IN THE KHUF/KBMG AREAS...BUT IT APPEARS ANY
IFR VISIBILITY RESTRICTIONS WILL REMAIN SOUTHWEST OF THE TERMINALS
CLOSER TO VORTICITY CENTER.
OTHERWISE...EXPECTING CEILINGS TO GRADUALLY LOWER OVERNIGHT AND INTO THE
MORNING HOURS ON FRIDAY...EVENTUALLY FALLING INTO THE MVFR CATEGORY TOWARDS
MIDDAY FRIDAY AS COLD ADVECTION DEVELOPS IN THE WAKE OF THE DISTURBANCE.
LIGHT SURFACE WINDS OVERNIGHT EXPECTED TO BECOME 260-280 DEGREES AT 10-13 KTS
BY MIDDAY FRIDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$TENTIAL
SYNOPSIS...JH
NEAR TERM...JH/NIELD
SHORT TERM...JH
LONG TERM....RYAN
AVIATION...JAS/RYAN
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1138 PM EST THU FEB 11 2016
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 330 PM EST THU FEB 11 2016
A COLD UPPER TROUGH OVER ONTARIO AND THE ST. LAWRENCE VALLEY WILL KEEP US
UNDER A NORTHWEST FLOW ALOFT AND TEMPERATURES COLDER THAN NORMAL THROUGH
EARLY NEXT WEEK. A CLIPPER WILL GIVE US A CHANCE OF LIGHT SNOW TOWARDS
DAYBREAK OVER WESTERN SECTIONS AND MOST AREAS FRIDAY. LAKE EFFECT
SNOW SHOWERS MAY LINGER TO MIDDAY SATURDAY ACROSS OUR NORTHEAST.
COLD HIGH PRESSURE WILL BUILD EAST ACROSS OUR REGION SATURDAY AND
SATURDAY NIGHT. AN APPROACHING AREA OF LOW PRESSURE WILL SPREAD
SNOW ACROSS OUR REGION SUNDAY INTO MONDAY. ANOTHER SYSTEM WILL
BRING A CHANCE OF SNOW MONDAY AND MONDAY NIGHT. FINALLY A FOURTH
SYSTEM WILL BRING A CHANCE OF SNOW OR MIXED PRECIPITATION AROUND THE
MIDDLE OF NEXT WEEK. TEMPERATURES WILL BEGIN TO MODERATE TOWARDS THE
MIDDLE OF NEXT WEEK AS OUR UPPER FLOW BECOMES MORE ZONAL.
&&
.NEAR TERM.../TONIGHT AND FRIDAY/
ISSUED AT 822 PM EST THU FEB 11 2016
GOING FORECAST IS IN EXCELLENT SHAPE. FLAKES MAY FLY ACROSS PORTIONS
OF CENTRAL INDIANA BY THE MORNING RUSH. FEEL CHANCE POPS HANDLE THIS
BEST HOWEVER AS THERE IS A LOT OF NEAR SURFACE DRY AIR TO OVERCOME.
WILL HAVE TO MONITOR FOR POSSIBLE IMPACTS TO FRIDAY MORNING COMMUTE
ACROSS THE AREA...ESPECIALLY AS HRRR AND NAM PROFILES INDICATE FIRST
FLAKES MAY BEGIN REACHING THE GROUND DURING THE HEART OF THE
COMMUTE. HOWEVER...RATES APPEAR UNLIKELY TO BE SUCH THAT RAPID
ACCUMULATION WOULD OCCUR...WHICH WOULD LIMIT POTENTIAL IMPACT.
PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 330 PM EST THU FEB 11 2016
HIGH PRESSURE CENTERED OVER ILLINOIS WILL MOVE EAST ACROSS INDIANA THIS
EVENING AND ON TO THE EAST BY MONDAY. A WEAK CLIPPER OVER THE UPPER
MIDWEST AND NORTHERN PLAINS WILL MOVE TO THE MIDDLE MISSISSIPPI VALLEY
LATE TONIGHT AND ACROSS THE OHIO VALLEY FRIDAY.
MOSTLY CLEAR CONDITIONS WERE OCCURRING ACROSS WESTERN SECTIONS THIS AFTERNOON
WHILE PARTLY CLOUDY CONDITIONS WERE THE RULE IN THE EAST. MID/HIGH CLOUDS
OVER THE MIDDLE MISSISSIPPI VALLEY WILL MOVE OUR WAY AND THICKEN OVERNIGHT.
ANY SNOW FROM THE CLIPPER PROBABLY WON`T REACH OUR AREA UNTIL AFTER 09Z AND
THIS WILL BE MAINLY ACROSS WESTERN AND SOUTHWEST AREAS.
SCATTERED LIGHT SNOW SHOWERS WILL SPREAD EAST ACROSS OUR REGION FRIDAY. AMOUNTS
WILL BE GENERALLY A QUARTER INCH. BUT SOME LAKE EFFECT SNOW SHOWERS ARE POSSIBLE
ACROSS OUR NORTHEAST LATE FRIDAY AS OUR FLOW BECOMES MORE NORTHERLY AND AMOUNTS
THERE WILL BE A LITTLE HIGHER BY LATE FRIDAY.
LOWERED TEMPERATURES SLIGHTLY CENTRAL AND EAST TONIGHT AS HIGH PRESSURE WILL
PROVIDE GOOD RADIATIONAL COOLING EARLY ON. OTHERWISE...A MOS BLEND OF TEMPERATURES
SEEM REASONABLE. WINDS WILL BE LIGHT TONIGHT AND THEN BECOME NORTHWEST WITH
GUSTS UP TO 25 MPH BY FRIDAY AFTERNOON AS A PRESSURE GRADIENT STRENGTHENS.
&&
.SHORT TERM.../FRIDAY NIGHT THROUGH SUNDAY/
ISSUED AT 330 PM EST THU FEB 11 2016
WE WILL REMAIN UNDER A COLD NORTHWEST FLOW FRIDAY NIGHT SATURDAY AS HIGH
PRESSURE OVER THE NORTHERN PLAINS BUILDS OUR WAY. MODELS INDICATE SOME FETCH OFF
OF LAKE MICHIGAN WHICH WILL PRODUCE SCATTERED LAKE EFFECT SNOW SHOWERS OVER
NORTHEAST SECTIONS. WHILE COLD AND DRY WEATHER WILL BE THE RULE ELSEWHERE.
MODELS INDICATE 850 TEMPERATURES OF -15 TO -21 CELSIUS SATURDAY AND -8 TO -12
CELSIUS SUNDAY. THIS WILL TRANSLATE TO HIGHS IN THE TEENS SATURDAY 20 TO 26
DEGREES SUNDAY. LOWS WILL BE MOSTLY IN THE SINGLE DIGITS BOTH FRIDAY AND
SATURDAY NIGHT. BUT LOWS NEAR ZERO ARE POSSIBLE SATURDAY NIGHT OVER NORTHEAST
SECTIONS AS CLOUDS MAY NOT ARRIVE THERE UNTIL LATE.
THE BIGGEST CONCERN WILL BE SNOW AMOUNTS SUNDAY AS AREA OF LOW PRESSURE MOVES
INTO THE UPPER MIDWEST AND A STRONGER CLIPPER MOVES OUR WAY. THE NAM/OPERATIONAL
GFS AND THE NEW EURO ALL INDICATE AN INCH OR TWO OF SNOW BY SUNDAY AFTERNOON...
WHILE THE CANADIAN HARDLY HAS ANYTHING AS MOST OF ITS PRECIPITATION IS FARTHER
SOUTHWEST. FOR NOW WILL GO WITH A BLEND. WILL RAISE POPS TO LIKELY OVER WEST
CENTRAL AND NORTHWEST AND GO WITH HIGH CHANCE POPS ELSEWHERE BY SUNDAY AFTERNOON.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 237 PM EST FEB 11 2016
AN ACTIVE WEATHER PATTERN IS IN PLACE FOR THE LONG TERM. MODEL
VARIABILITY WITH THIS SYSTEM HAS BEEN AND CONTINUES TO BE FAIRLY
HIGH...AS DESCRIBED FURTHER BELOW. ESSENTIALLY AN UPPER WAVE WILL
MOVE SOMEWHERE THROUGH THE GREAT LAKES WITH AN ASSOCIATED SURFACE
SYSTEM SOMEWHERE TO ITS SOUTH AND THIS WILL BRING SNOW CHANCES TO
THE AREA. HOW MUCH SNOW AND WHERE IS STILL VERY MUCH IN QUESTION.
GFS ENSEMBLE MEMBERS ARE CLUSTERING MORE WITH THE HIGHER AMOUNTS
OVER NORTHERN INDIANA WITH A FEW MEMBERS PUTTING THE MAX ACROSS
THE CENTRAL PART OF THE STATE. 24 HOUR MAX AMOUNTS IN THE GEFS
VARY FROM 2 INCHES TO AROUND 6 INCHES. THE 12Z OPERATIONAL GFS HAS
A MAX OF AROUND 4+ INCHES ACROSS THE NORTHERN THIRD OF THE STATE
WITH 2-3 INCH AMOUNTS CENTRAL AND SHARPLY LESS SOUTH. THE 12Z
ECMWF THOUGH SHOWS SNOWFALL MAXES TO THE NORTH AND SOUTH WITH THE
IND CWA IN A LOCAL MINIMUM WITH AROUND 1-1.5 INCHES OR LESS. ECM
RUNS HAVE BEEN BOUNCING FROM A SOLUTION WITH A MAX WELL SOUTH OF
THE FORECAST AREA TO HIGHEST AMOUNTS ACROSS THE SOUTHERN COUNTIES.
0Z CANADIAN ENSEMBLE AVERAGE FAVORS THE SOLUTION THAT PUTS THE MAX
WELL SOUTH OF THE AREA. 0Z GFS CIPS ANALOGS SHOW THE HIGHEST
PROBABILITY FOR 2 INCHES OR GREATER IS ACROSS THE NORTHERNMOST
COUNTIES OF THE FORECAST AREA AND PROBABILITIES TAPER OFF HEADING
SOUTH.
FORECAST MODELS ARE FAIRLY CONSISTENT IN SHOWING DECENT
FORCING DURING THE SUNDAY NIGHT PERIOD SO WILL INCREASE POPS TO
LIKELY DURING THAT TIME. AT THIS MOMENT THOUGH WILL NOT CHANGE
SNOWFALL AMOUNTS FROM THOSE GIVEN BY THE BLENDED INITIALIZATION.
SNOW CHANCES STAY AROUND FOR MONDAY THROUGH TUESDAY IN CYCLONIC
FLOW. SHOULD SEE A SLOW WARMING TREND THROUGH THE WEEK WITH SMALL
CHANCES FOR RAIN OR SNOW TUESDAY AND WEDNESDAY.
&&
.AVIATION /DISCUSSION FOR THE 120600Z TAFS/...
ISSUED AT 1138 PM EST THU FEB 11 2016
UPPER DISTURBANCE CURRENTLY DROPPING SOUTHEAST THROUGH NORTHERN MISSOURI
IS EXPECTED TO SETTLE INTO WESTERN KENTUCKY AROUND SUNRISE FRIDAY. COULD
BE SOME LIGHT SNOW AT THE TERMINALS ROUGHLY 121000Z-121600Z ASSOCIATED WITH
THIS FEATURE...MAAINLY IN THE KHUF/KBMG AREAS...BUT IT APPEARS ANY IFR
VISIBILITY RESTRICTIONS WILL REMAIN SOUTHWEST OF THE TERMINALS CLOSER TO
VORTICITY CENTER.
OTHERWISE...EXPECTING CEILINGS TO GRADUALLY LOWER OVERNIGHT AND INTO THE
MORNING HOURS ON FRIDAY...EVENTUALLY FALLING INTO THE MVFR CATEGORY TOWARDS
MIDDAY FRIDAY AS COLD ADVECTION DEVELOPS IN THE WAKE OF THE DISTURBANCE.
LIGHT SURFACE WINDS OVERNIGHT EXPECTED TO BECOME 260-280 DEGREES AT 10-13 KTS
BY MIDDAY FRIDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH/NIELD
SHORT TERM...JH
LONG TERM...CP
AVIATION...JAS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1143 PM CST THU FEB 11 2016
...AVIATION UPDATE...
.UPDATE...
ISSUED AT 803 PM CST THU FEB 11 2016
NARROW BAND OF MOSTLY LIGHT SNOW HAS SET UP FROM JUST SW OF DMX
SE THROUGH CENTERVILLE AND OTTUMWA S-SE TO NEAR QUINCY IL AS SEEN
ON AREA RADARS. IN THE DVN FORECAST AREA...SNOW HAD BEGUN OVER
THE PAST HOUR IN FAIRFIELD WITH UPSTREAM VISIBILITIES AROUND 2 1/2
TO 3SM IN ADJACENT S CENTRAL IA . THE LATEST HRRR...RAP AND NAM
HIGH RES MODELS KEEP THIS AXIS OF LIGHT SNOW...CONFINED TO SE
IA...NE MO INTO W CENTRAL IL...MAINLY NORTH OF HIGHWAY 34. THIS IS
THE AXIS OF MAIN UPPER LEVEL FORCING...WHICH IS NUDGED UP AGAINST
A DEEP DRY AIRMASS TO THE NORTHEAST. SURFACE DEWPOINTS OVER
EASTERN IA AND POINTS EAST AND NORTH WERE ONLY IN THE SINGLE
DIGITS...AND THE KDVN 00Z/12 SOUNDING INDICATED A DEEP DRY LAYER
BELOW 700 MB.
THIS WILL LIKELY KEEP MEASURABLE SNOW LIMITED TO SE IA...FAR NW MO
AND W CENTRAL IL OVER THE NEXT SEVERAL HOURS AND HAVE BACKED DOWN
ON SNOW AMOUNTS OVER THE CENTRAL AND NORTH FOR OVERNIGHT TO TRACE
AMOUNTS AT BEST. WILL HAVE TO WATCH A WEAK AREA OF LIFT THE NW
FLOW ALOFT PRODUCING LIGHT SNOW IN THE MSP AREA FOR MUCH LATER
TONIGHT AS IT PROGRESSES TOWARD FAR EASTERN IA AND NW IL. WILL
HANDLE THIS WITH VERY LOW POPS AND KEEP A MENTION OF AT LEAST
FLURRIES IN ALL AREAS THROUGH THE OVERNIGHT.
&&
.SYNOPSIS...
ISSUED AT 327 PM CST THU FEB 11 2016
HIGH PRESSURE CENTERED OVER THE EASTERN CWA THIS AFTERNOON AS
LEADING TO CLEAR SKIES AND DRY WEATHER FOR MOST OF THE AREA. A
FAST MOVING CLIPPER IS FORECAST TO AFFECT THE AREA LATER TODAY AND
TONIGHT AND WILL BE THE MAIN FORECAST CONCERN IN THE SHORT TERM
FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 327 PM CST THU FEB 11 2016
MAIN FORECAST CONCERN FOR THE SHORT TERM ARE THE CHANCES FOR SNOW
ASSOCIATED WITH A FAST CLIPPER ACROSS THE AREA TODAY. DRY AIR IN
PLACE WITH THE HIGH OVERHEAD WILL LIMIT OVERALL SNOWFALL TOTALS TO
AROUND AN INCH...WITH LOCALLY HIGHER AMOUNTS JUST OVER AN INCH.
HIRES GUIDANCE IS IN GOOD AGREEMENT THAT THIS WILL START NEAR 00Z
AND BE OUT OF THE AREA BY 08Z.
GUIDANCE TODAY HELD STRONG WITH THE CONSENSUS ON TIMING AND
STRONGEST FORCING WILL REMAIN ACROSS OUR FAR SOUTHERN ZONES. WWD
HAS AROUND AN INCH OF SNOW FOR THIS AREA AND OUR FORECAST
REPRESENTS THIS. LATEST RUNS OF THE HRRR SUGGESTS THAT THE BEST
SNOW WILL BE OUT OF THE AREA BY 06Z WITH LINGERING FLURRIES
THROUGH 09Z ACROSS THE FAR SOUTHERN CWA. WINDS WILL REMAIN LIGHT
SO LITTLE TO NO IMPACTS ARE EXPECTED FROM THIS SNOW. ANY SNOW THAT
ACCUMULATES SHOULD BE DONE BY THE EARLY HOURS.
FRIDAY WILL BE QUIET AND SLIGHTLY WARMER..WITH CLEARING SKIES.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 327 PM CST THU FEB 11 2016
FRIDAY NIGHT...LATEST SUITE OF 12Z RUN MODELS SUGGEST 1045 MB ARCTIC
HIGH PRESSURE STILL ON TRACK TO SURGE DOWN THE UPPER TO MID MS
RIVER VALLEY FRI NIGHT INTO SAT WITH A SCOURING EFFECT. THIS
FEATURE TO COLD DUMP LLVL TEMPS/THICKNESS VALUES TO PRODUCE SUB-
ZERO LOWS ACRS MOST OF THE CWA...BUT SOME CONCERN THAT ONGOING
MIXING SFC WINDS IN INCOMING HIGH PRESSURE GRADIENT TO LIMIT A
COMPLETE BOTTOM OUT. BUT DUE TO BRUTE FORCE COLD AIR
ADVECTION...WILL STILL GO WITH LOWS FROM 5 TO NEAR 10 BELOW ZERO
ACRS THE NORTHWESTERN THIRD OF THE CWA...0 TO 5 BELOW ALONG AND
NORTH OF I80...AND TO THE LOW SINGLE DIGITS ABOVE ZERO IN THE
SOUTHERN CWA. SFC WINDS DECREASING TO 7-10 MPH TOWARD SUNRISE SAT
STILL TO PRODUCE ADVISORY LEVEL WIND CHILLS ACRS AT LEAST THE
NORTHWESTERN THIRD OF THE DVN CWA...AND POSSIBLY ALONG THE HWY 20
CORRIDOR IN NW IL.
SATURDAY AND SUNDAY...THE ARCTIC HIGH OVERHEAD WILL MAKE FOR
TEMPORARY CLEAR AND CALM/LIGHT WIND CONDITIONS FOR FIRST PART OF THE
DAY SAT...WITH HIGH CLOUDS ON THE INCREASE AS THE AFTERNOON
PROGRESSES. THIS AHEAD OF THE ORGANIZING SHORT WAVE UPPER TROF THAT
WILL LOOK TO PROPAGATE TOWARD THE SOUTHWESTERN GRT LKS AND MID MS
RIVER VALLEY ON SUNDAY IN BROADENING WEST-NORTHWESTERLY STEERING
FLOW. THE VARIOUS MEDIUM RANGE SOLUTIONS SUGGEST SOME TYPE OF
ASSOCIATED WARM AIR ADVECTION WING OF SNOW WILL LOOK TO TRY TO GET
INTO THE WESTERN OR SOUTHWESTERN CWA BY EARLY SAT EVENING...BUT
FEEL MODELS MAY BE TOO QUICK WITH THIS TAKING INTO ACCOUNT
STRENGTH OF DRY SFC RIDGE AXIS STILL ON THE MOVE OVER AND EAST OF
THE CWA AT THAT TIME. BUT BY MIDNIGHT SAT NIGHT...BOTH THE 12Z RUN
ECMWF AND GEM SUGGEST SOME LIGHT SNOW ACCUMS STARTING TO TAKE
PLACE ALREADY IN THE FAR SOUTHWESTERN CWA. AGAIN SIDING WITH THE
12Z GEM/ECMWF WHICH ARE IN DECENT AGREEMENT...THE WAA WING OF SNOW
AHEAD OF THE MAIN UPPER TROF WILL LOOK TO CONTINUE TO SPREAD
EASTWARD ACRS MUCH OF THE WESTERN 2/3S OF THE CWA THROUGH 12Z
SUNDAY...BUT MAY GET ERODED SOME AS IT DOES BY ONGOING DRY AIR IN
PLACE AND ALSO SOME IMPACT OF MUCH OF THE INITIAL LIFT GOING INTO
THE TOP-DOWN SATURATION PROCESS. THE LATEST GEM MAY HAVE THE BEST
HANDLE ON THIS IDEA WITH JUST A DUSTING TO HALF INCH WEST OF THE
MS RIVER BY 12Z SUNDAY...BUT WILL GO WITH A FEW TENTHS TO NEAR AN
INCH SOUTHWEST OF A LINE FROM DBQ...TO THE QUAD CITIES...AND TO
MACOMB IN WESTERN IL.
THEN THE MAIN SNOW EVENT WITH THE UPPER TROF WILL LOOK TO OCCUR ON
SUNDAY AND WILL CONTINUE TO ADJUST POPS UP INTO LIKELY OR EVEN
CATEGORICAL. BUT THE 12Z RUN AMERICAN MODELS/ESPECIALLY THE 12Z GFS/
WHICH HINT AT HIGH END ADVISORY OR EVEN LOW END WARNING CRITERIA
AMOUNT SNOWS BY SUNDAY EVENING COMBINING THE TWO SNOW MAKING
PROCESSES...SEEM TOO WET...TOO STRONG LOOKING AT MID AND UPPER LEVEL
JET DYNAMICS MORE FAVORABLE TO THE SOUTH...AND THEIR DEEP SATURATION
IN THE DENDRITIC GROWTH ZONE FOR MUCH OF SUNDAY MORNING INTO EARLY
AFTERNOON. SO CURRENTLY FAVOR A BLEND OF THE 12Z GEM/ECMWF MOISTURE
AND FORCING PROFILES WHICH SUGGEST MOST OF THE CWA TO GET 1-3 OR 2-4
INCHES OF SNOW BY SUNDAY EVENING. INCREASING SOUTH WINDS OF 15-20
MPH MAY PRODUCE SOME DRIFTING TROUBLE BY SUNDAY AFTERNOON AS
WELL...SO THERE MAY BE A NEED FOR AN EVENTUAL ADVISORY EVEN WITH THE
LIGHTER AMOUNTS PRODUCED BY THESE FAVORED SOLUTIONS. STILL 1-3 MORE
MODEL RUNS NEEDED TO FURTHER DEFINE THIS SNOW EVENT FOR MORE
CONFIDENCE.
MONDAY THROUGH NEXT THU...AS THE PASSING TROF CONTINUES TO EVOLVE
ALONG AND EAST OF THE REGION EARLY NEXT WEEK..RESULTANT MAJOR STORM
SHOULD TAKE OFF WELL TO THE EAST/SOUTHEAST OF LOCAL AREA OF CONCERN.
BUT THERE MAY BE SOME NUISANCE LIGHT SNOW AT TIMES ACRS THE AREA IN
THE WAKE OF THE MAIN SYSTEM...OR EVEN A SECONDARY WEAK CLIPPER LATE
MONDAY INTO TUE. LONGER RANGE INDICATIONS THEN SUGGEST THE CLIPPER
INDUCING NORTHWESTERLIES WILL EVENTUALLY GIVE WAY TO MILDER UPPER
RIDGING BY MID TO LATE NEXT WEEK...BUT THE TREND HAS BEEN TO DELAY
IT/S ARRIVAL ESPECIALLY IF RE-ENFORCING TROFFINESS ESTABLISHES ACRS
THE WESTERN GRT LKS TUE INTO WED LIKE SOME OF THE LATEST ENSEMBLES
SUGGEST. ..12..
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1143 PM CST THU FEB 11 2016
A WEAK UPPER LEVEL DISTURBANCE DIVING SOUTHEAST OUT OF MN IS
EXPECTED TO BRING ANOTHER ROUND OF LOWERED CIGS AND POTENTIAL
FLURRIES LATER TONIGHT INTO EARLY FRIDAY MORNING. THE LATEST
FORECASTS HAVE A LOW CONFIDENCE PERIOD OF MVFR CIGS...AROUND 2500
FT AGL...CENTERED ON THIS FEATURE. EARLIER ON...LIGHT SNOW
ASSOCIATED WITH A SEPARATE SYSTEM EXITING INTO MO AND IL WILL
AFFECT PRIMARILY THE BRL SITE EARLY...FOLLOWED BY A SEVERAL HOUR
PERIOD OF VFR CONDITIONS AT ALL SITES. ON FRIDAY...AN ARCTIC COLD
FRONT WILL PUSH THROUGH DURING THE MORNING HOURS. THIS WILL BE
FOLLOWED BY BRISK NORTHWEST WINDS AND FALLING TEMPERATURES. THERE
MAY ALSO BE FLURRIES WITH THIS FEATURE...WHICH ARE NOT INCLUDED IN
THE CURRENT FORECASTS. WINDS WILL LIKELY DIMINISH IN THE EVENING
WITH CLEARING SKIES AS ARCTIC HIGH PRESSURE BUILDS INTO THE
REGION.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...SHEETS
SYNOPSIS...GIBBS
SHORT TERM...GIBBS
LONG TERM...12
AVIATION...SHEETS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1125 PM EST THU FEB 11 2016
.UPDATE...
ISSUED AT 1100 PM EST THU FEB 11 2016
HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS.
MUCH OF THE 0Z GUIDANCE AND RECENT SHORT TERM MODEL RUNS HAVE
SHIFTED THE AXIS OF HEAVIER SNOW TO THE SOUTH...AND THIS WOULD PUT
THE BEST CHANCE FOR ONE INCH OF ACCUMULATION OR MORE ON FRI
MORNING ALONG THE SOUTHERN TIER OF COUNTIES IN THE CURRENT
ADVISORY. THIS SHOULD AFFECT THE MORNING COMMUTE. HOWEVER...SNOW
SHOWERS ARE ALSO POSSIBLE FURTHER NORTH...POSSIBLY AFFECTING THE
TAIL END OF THE MODEL COMMUTE.
UPDATE ISSUED AT 830 PM EST THU FEB 11 2016
HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS.
TIMING OF THE ONSET OF SNOW AND ASSOCIATED POPS HAS BEEN FRESHENED
UP LATE TONIGHT AND EARLY ON FRI BASED ON RECENT MODEL TRENDS.
18Z AND RECENT HRRR RUNS GENERALLY KEEP THE HIGHEST QPF AND BEST
CHANCES FOR MEASURABLE SNOW SOUTH OF THE HAL ROGERS PARKWAY AND KY
80 CORRIDOR. IN THIS AREA...AROUND AN INCH IS ANTICIPATED THROUGH
NOON ON FRIDAY. FURTHER NORTH...LESSER AMOUNTS ARE ANTICIPATED.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 255 PM EST THU FEB 11 2016
19Z SFC ANALYSIS SHOWS AN AREA OF HIGH PRESSURE SLIPPING INTO THE
OHIO VALLEY. TO THE SOUTH AND WEST OF THIS...LOW PRESSURE IS
STARTING TO DEVELOP. ON SATELLITE...SOME LOWER AND MID LEVEL
CLOUDS ARE CLEARING OUT OF THE AREA WHILE THE NEXT ROUND OF
CLOUDS ARE HEADING TOWARD THE AREA FROM THE NORTHWEST. THE PARTIAL
SUNSHINE OF TODAY HELPED TEMPERATURES TO REBOUND INTO THE MID AND
UPPER 20S NORTH AND UPPER 20S TO LOWER 30S IN THE SOUTH.
DEWPOINTS...MEANWHILE...ARE RUNNING IN THE 10 TO 15 DEGREE RANGE
WITH LIGHT WINDS...GENERALLY FROM THE NORTHWEST.
THE MODELS ARE IN GREAT AGREEMENT ALOFT WITH THE EASTERN TROUGH
RETREATING TO THE NORTH TONIGHT. IN THE NORTHWEST FLOW THAT
FOLLOWS FOR KENTUCKY A QUICK HITTING SHORTWAVE WILL PUNCH THROUGH
THE TENNESSEE VALLEY FRIDAY MORNING. THE CORE OF THIS WILL MAINLY
PASS WEST OF EASTERN KENTUCKY...BUT ALSO BRING SOME HEIGHT FALLS
TO THE AREA FOR THE DAY. ANOTHER SHARP TROUGH TO THE NORTH WILL
SWING THROUGH THE GREAT LAKES LATER FRIDAY INTO SATURDAY MORNING
WITH ADDITIONAL STREAMS OF ENERGY BRUSHING THE NORTHEAST PORTION
OF THE STATE. GIVEN THE MODEL AGREEMENT WILL FAVOR A GENERAL
BLEND ALONG WITH A LEAN TOWARD THE HIGHER RESOLUTION NAM12 AND
HRRR.
SENSIBLE WEATHER WILL FEATURE A QUIET AND CHILLY EVENING WITH
LIGHT SNOW DEVELOPING TOWARD DAWN IN THE WEST AND SHORTLY AFTER IN
THE EAST. THE CLIPPER SYSTEM BRINGING THE SNOW WILL TARGET THE
SOUTHERN PORTION OF THE AREA FRIDAY MORNING WITH AROUND AN INCH OF
SNOW EXPECTED. THE SNOW SHOULD TAPER OFF BY NOON FOR MOST OF
EASTERN KENTUCKY...BUT COULD LINGER IN THE FAR NORTHEAST.
ADDITIONAL SNOW SHOWERS WILL BE POSSIBLE IN THE EVENING AND
OVERNIGHT INTO SATURDAY MORNING...WITH ACCUMULATIONS MAINLY
CONFINED TO THE FAR EASTERN PARTS OF THE AREA DUE TO UPSLOPE
FLOW. THIS FIRST BATCH OF SNOW WILL BE ROBUST FOR A FEW HOURS
DURING THE MORNING AND RIGHT THROUGH THE MORNING COMMUTE HOURS.
ON ACCOUNT OF THIS...AND AS IT TARGETS SOME OF THE MAIN
THOROUGHFARES IN OUR CWA...HAVE ISSUED AN ADVISORY FOR OUR
SOUTHERN TIER OVER TO PIKE COUNTY FROM 10Z THROUGH 17Z. AN SPS
WILL BE ISSUED FOR THE REMAINDER OF THE AREA FOR LATE TONIGHT
INTO FRIDAY MORNING. AN ADDITIONAL SPS OR ADVISORY MAY BE NEEDED
FOR LATER FRIDAY INTO EARLY SATURDAY FOR OUR UPSLOPE AREAS. WILL
DETAIL ALL THIS IN THE HWO...AS WELL.
AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR THE T/TD/WIND
GRIDS THROUGH THE NIGHT BEFORE FAVORING THE SUPERBLEND THEREAFTER.
ONLY MADE SOME MINOR ADJUSTMENTS TO THE TEMPS TONIGHT AND FRIDAY
NIGHT DUE TO TERRAIN DIFFERENCES BOTH NIGHTS. AS FOR POPS...WENT
ON THE HIGH SIDE OF MOS GUIDANCE THROUGH THE PERIOD...GENERALLY IN
LINE WITH THE MET TONIGHT/FRIDAY AND MUCH ABOVE FRIDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 359 PM EST THU FEB 11 2016
...ANOTHER WINTER STORM ON TAP FOR EARLY NEXT WEEK...
ARCTIC AIR WILL BE ENTRENCHED OVER THE AREA BY SATURDAY...SETTING
UP A VERY COLD DAY WHERE WE WILL LIKELY EXCEED OUR COLDEST HIGH
TEMPERATURES ON RECORD FOR THE DATE. HIGHS WILL STRUGGLE TO REACH
THE MID TO UPPER TEENS. GIVEN THE COLD AIRMASS AND CONTINUED
NORTHWEST FLOW...SOME FLURRIES/SNOW SHOWERS WILL REMAIN POSSIBLE
THROUGH THE DAY AND EVEN INTO THE EVENING...BUT SHOULD NOT POSE
MUCH OF AN IMPACT TO THE AREA. A COLD NIGHT WILL BE SEEN SATURDAY
NIGHT...WITH SOME RECOVERY IN TEMPERATURES EXPECTED ON SUNDAY.
HOWEVER...MID/HIGH CLOUDS WILL INCREASE AND WE COULD START SEEING
SOME FLURRIES/LIGHT SNOW SHOWERS DURING THE DAY SUNDAY. BY SUNDAY
NIGHT...A WARM FRONT WILL PUSH NORTH ACROSS THE AREA WITH LIGHT
SNOW BREAKING OUT ACROSS THE REGION. THIS LOOKS LIKE IT COULD
PRODUCE A LIGHT COATING OF SNOW ACROSS MOST OF THE AREA INTO EARLY
MONDAY MORNING.
THIS BRINGS US INTO EARLY NEXT WEEK...WHERE CONFIDENCE REMAINS
SOMEWHAT LOW AS MODELS ARE STILL SORTING OUT ALL THE DIFFERENCES.
12Z GFS/ECMWF HAVE TRENDED TOWARD A MORE NORTHERN TRACK OF THE
LOW...WITH MILDER CONDITIONS SPREADING INTO EASTERN KENTUCKY. THIS
MAY SUPPORT A CHANGEOVER TO RAIN ON MONDAY...OR FREEZING RAIN IF
TEMPERATURES IN THE VALLEYS DON`T RECOVER FAST ENOUGH.
HOWEVER...THE TRACK OF THE SYSTEM WILL DETERMINE EXACTLY WHERE
SNOW/FREEZING RAIN/RAIN FALLS...SO UNTIL MODELS COME INTO
AGREEMENT...TRYING TO PIN DOWN DETAILS WILL BE VERY DIFFICULT.
REGARDLESS...THOSE WITH PLANS EARLY NEXT WEEK SHOULD STAY AWARE OF
THE POTENTIAL FOR A WINTER STORM IN THE COMING DAYS AND CHECK BACK
WITH THE FORECAST. AS THIS SYSTEM DEPARTS BY TUESDAY...IT LOOKS
LIKE A WEAK TROUGH DEVELOPS OVER THE AREA AGAIN WITH POTENTIAL
RAIN/SNOW SHOWERS LINGERING INTO MIDWEEK. BY THE END OF THE
WEEK...THE TROUGH EXITS WITH STRONG RIDGING BUILDING BACK INTO THE
AREA. THIS WILL YIELD A MORE SIGNIFICANT WARM UP BY THE END OF
NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 735 PM EST THU FEB 11 2016
MVFR SHOULD PREVAIL THROUGH AT LEAST THE FIRST 9 TO 12Z HOURS OF
THE PERIOD. HOWEVER...CIGS SHOULD THEN LOWER INTO THE MVFR RANGE
TOWARD DAWN AS A CLIPPER SYSTEM BRINGS SOME SNOW TO THE AREA. THIS
SHOULD AFFECT THE FOUR SOUTHERNMOST OF THE TAF SITES. THE BEST
CHANCES FOR LOW VIS AND CIGS WILL BE THROUGH THE SOUTHERN HALF OF
THE CWA PEAKING IN THE 12Z TO 16Z RANGE. WINDS WILL BE RELATIVELY
LIGHT AT 5 TO 10 KT DURING THE PERIOD...GENERALLY FROM THE WEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 5 AM TO NOON EST FRIDAY FOR KYZ068-
069-079-080-083>088-110-112>118-120.
&&
$$
UPDATE...JP
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1150 PM CST THU FEB 11 2016
.UPDATE:
Issued at 859 PM CST Thu Feb 11 2016
Have made some minor adjustments to snowfall based on this
evening`s radar and satellite trends. Water vapor is showing a mid
level vort max currently dropping southeastward out of eastern
Nebraska into northwestern Missouri with a deformation axis
extending from northeast Missouri into west central Iowa. It is
taking some time for the snow to overtake the dry air in the low
levels, so only reports of snow so far in the CWA have flurries
over northeast Missouri. Do think the accumulating snow currently
over Iowa will move into northeast Missouri and west central
Illinois shortly. It still appears the the intensity of the
snowfall will weaken as it moves southeast per the recent runs of
the the RAP. Do not expect much accumulation of snow as far south
at I-70 before midnight...so have shifted the 1 inch totals
slightly northward into northeast Missouri and west central
Illinois with lesser amounts to the south. It still will be a cold
night, so even light snowfall amounts could impact travel. Also
watching second area of radar returns over western Missouri which
has only one or two reports of light snow with it. Any snow
accumulations with it should be light as it moves across the
southern CWA over the next few hours.
Britt
&&
.SHORT TERM: (Through Late Tonight)
Issued at 1230 PM CST Thu Feb 11 2016
A northwest flow shortwave now dropping southeastward into western
SD will move quickly through our area tonight. Light snow will
spread southeastward into northeast MO early this evening, then
through the St Louis metro area around midnight. Still looking like
a quick shot of dry, powdery snow with most places picking up to 1
inch of accumulation, but there may be a narrow band of 1-2 inches
extending from near IRK southeast through the St Louis metro area.
Latest NAM and HRRR model runs have the band a little further west
than previous model runs. Most of the accumulating snow should
shift southeast of our forecast area by 12Z Friday. Low
temperatures will be similar to the previous night, and around 5
degrees below normal.
GKS
.LONG TERM: (Friday through Next Thursday)
Issued at 316 PM CST Thu Feb 11 2016
A strong cold front will move southeastward through our forecast
area on Friday with strengthening winds as the surface pressure
gradient tightens as a strong 1040-1045 mb surface high builds
southeastward into the area from the northern Plains behind the cold
front. Temperatures may begin to fall in northeast MO behind the
front already by Friday afternoon. Much colder temperatures are
expected for Friday night and Saturday with wind chills down to
around 10 below zero late Friday night and early Saturday morning
across northeast MO and west central IL. Snow should spread
southeastward into at least northeast MO and west central IL late
Saturday night as low-mid level warm air advection increases ahead
of an approaching northern stream shortwave. It still appears that
the ECMWF model is a little too quick bringing precipitation into
our forecast area already be Saturday afternoon and evening with an
initially very dry boundary layer on the backside of the surface
ridge. The better chance of precipitation should occur on Sunday as
a southwesterly low level jet brings increasing low level moisture
into our area ahead of the shortwave. It is too early to pin down
exact snow totals, but it initially appears that 2-4 inches is
possible across northeast MO and west central IL with lesser amounts
of 1-2 inches further south for Saturday night and Sunday. Another
round of precipitation is expected, mainly on Monday, as a southern
stream shortwave and associated surface low pass south of our area.
This precipitation should be confined mainly to southeast MO and
southwest IL. With temperatures trending up as we head into the
next work week there may also be precipitation type issues with a
mix of snow, sleet and rain possible. Will keep the rest of the
forecast dry with a warming trend, although the ECMWF model does
depict some weaker weather systems bringing a brief period or two of
light QPF to our area. The GFS model is dry for the remainder of
the period after Monday with a dry cold frontal passage on Tuesday
afternoon and evening. Both the GFS and ECMWF models depict a warm
weather pattern by Thursday with upper level ridging over the region
along with strong s-swly low level winds likely leading to well
above normal temperatures.
GKS
&&
.AVIATION: (For the 06z TAFs through 06z Friday Night)
Issued at 1149 PM CST Thu Feb 11 2016
Snow will continue to move quickly across the area during the
overnight hours reducing visibilities to MVFR or possibly IFR at
times. The snow will move into the St. Louis area terminals in the
next hour and out by 09-11Z. The snow will also move out of KUIN
and KCOU by 06-08Z. Snow accumulations of up to 1 inch are
possible. Then MVFR ceilings are expected to persist through the
morning hours before drier air moves in and allows VFR conditions
to develop.
Specifics for KSTL: An area of snow is expected to move into the
terminal between 06-07Z and move out by 10Z. Any snow
accumulations are expected to be less than an inch. Then MVFR
ceilings are expected to persist through the morning hours before
drier air moves in and allows VFR conditions to develop.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
320 AM CST FRI FEB 12 2016
.SYNOPSIS...
ISSUED AT 320 AM CST FRI FEB 12 2016
ARCTIC HIGH PRESSURE CONTINUES TO BUILD SOUTH FROM THE DAKOTAS AND
MINNESOTA INTO NEBRASKA. AT 08Z...THE LEADING EDGE OF THE FRONT WAS
ANALYZED FROM NEAR PINE RIDGE SOUTH DAKOTA THROUGH NORTH PLATTE THEN
SOUTHEAST ACROSS NCTRL KS. A LARGE AREA OF STRATUS EXTENDS NORTH AND
EAST OF THE FRONT. NO INDICATION YET OF FOG DEVELOPMENT IN WESTERN
NEBRASKA. THE RAP AND HRRR MODELS BOTH SUGGEST DEVELOPMENT NEAR THE
WESTERN EDGE OF THE STRATUS ALONG ADVANCING COLD FRONT IN THE
WESTERN SANDHILLS INTO SOUTHWEST NEBRASKA THIS MORNING. TEMPERATURES
RANGING FROM 26 TO 32 ACROSS WESTERN NEBRASKA...WITH COLDER TEENS
REPORTED IN EASTERN SOUTH DAKOTA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CST FRI FEB 12 2016
THE MAIN FORECAST CONCERNS WILL BE THE BACKDOOR COLD FRONT FORECAST
TO PUSH INTO THE WESTERN NEBRASKA PANHANDLE AND NORTHEAST COLORADO
BY LATE THIS AFTERNOON AND ITS EFFECTS ON HIGH TEMPERATURES ACROSS
WESTERN NEBRASKA TODAY. ONLY MINOR ADJUSTMENTS TO HIGHS TODAY. NEAR
38 IN THE SWRN TIER OF COUNTIES IN CLOSER PROXIMITY TO THE FRONT.
LOWER 20S IN BOYD AND NERN HOLT COUNTY WHERE TEMPERATURES WILL
ACTUALLY HOLD STEADY THROUGH THE DAY FROM THIS MORNINGS LOWS.
FOR TONIGHT...A WARM FRONT WILL BEGIN TO PUSH EAST INTO WESTERN
NEBRASKA. WITH WIDESPREAD STRATUS ALREADY IN PLACE...CONDITIONS WILL
BE FAVORABLE FOR PATCHY FREEZING DRIZZLE TO BEGIN DEVELOPING DUE TO
A LACK OF ICE CRYSTALS INTRODUCED FROM ALOFT. THE PATCHY FREEZING
DRIZZLE FORECAST TO BEGIN LATE THIS EVENING MAINLY WEST OF A LINE
FROM GORDON THROUGH NORTH PLATTE...ADVANCING FURTHER EAST TO NEAR
VALENTINE THROUGH BROKEN BOW BY LATE TONIGHT. WHERE SOME SATURATION
DOES EXIST UP INTO THE DENDRITIC LAYER...A 20 TO 30 PERCENT CHANCE
FOR LIGHT SNOW ACROSS THE EASTERN TWO THIRDS OF THE FORECAST AREA.
THERE WILL BE AN AREA IN BETWEEN WHERE FREEZING DRIZZLE AND LIGHT
SNOW MAY BOTH OCCUR...MAINLY ACROSS WESTERN CHERRY COUNTY SOUTH
THROUGH THE CENTRAL SANDHILLS INTO SOUTHWESTERN NEBRASKA. SINCE ONLY
A SMALL AMOUNT OF FREEZING DRIZZLE CAN IMPACT TRAVEL...WILL CONTINUE
TO HIGHLIGHT THE POTENTIAL FOR THE LIGHT FREEZING DRIZZLE TONIGHT
INTO SATURDAY MORNING IN A SPECIAL WEATHER STATEMENT AND THE
HAZARDOUS WEATHER OUTLOOK.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 320 AM CST FRI FEB 12 2016
12Z SATURDAY AND BEYOND. SATURDAY WILL BE ANOTHER TRANSITION DAY AS
AN ELEVATED WARM FRONT LIFTS EAST ACROSS THE SANDHILLS.
HOWEVER...OUTSIDE OF THE EASTERN PANHANDLE AND WESTERN
SANDHILLS...ALL OTHER LOCATIONS WILL CONTINUE TO SEE TEMPERATURES
BELOW FREEZING. THIS WILL FACILITATE A CONTINUED MENTION
OF FREEZING DRIZZLE INTO THE EARLY AFTERNOON AS SOUNDINGS
INDICATE SATURATION BELOW THE DGZ WHERE THERE/S WEAK OMEGA. WHERE
SUFFICIENT SATURATION IS SHOWN IS ACROSS OUR NORTHEASTERN ZONES
WHERE LIGHT SNOW IS FORECAST. THE MODELS ONLY SUGGEST A FEW
HUNDRETHS AT MOST QPF...AND WITH VERY WEAK LIFT SEEN...SNOW
ACCUMULATIONS SHOULD ONLY AMOUNT TO A FEW TENTHS AT BEST.
ADDITIONAL SNOW CHANCES ARE POSSIBLE ACROSS OUR FAR NORTHERN
ZONES SATURDAY EVENING INTO EARLY SUNDAY AS A FAST MOVING MID-
LEVEL DISTURBANCE DROPS SOUTHEAST ACROSS THE DAKOTAS. THE MODELS
CONTINUE TO INDICATE THE BEST FORCING AND MOISTURE NORTH OF THE
BORDER ACROSS THE DAKOTAS...SO ONLY A FEW TENTHS ADDITIONAL SNOW
ACCUMULATIONS ARE EXPECTED.
WARMING TEMPERATURES ARE FORECAST FOR SUNDAY AS H85 T/S ARE SHOWN TO
CLIMB BACK ABOVE 0C FOR THE ENTIRE CWA. HIGHS IN THE 40S ARE
FORECAST. SUNDAY EVENING...THE MODELS DEPICT A FAST MOVING MID-
LEVEL DISTURBANCE DROPPING SOUTHEAST ACROSS THE HIGH PLAINS
OF COLORADO INTO WESTERN KANSAS. AT THIS POINT...FORCING IS TOO
WEAK WITHIN THE CWA FOR PRECIPITATION...BUT THE 00Z MODELS HAVE
TRENDED SLIGHTLY EAST WITH THE PROJECTED QPF. WILL NEED TO
MONITOR CLOSELY AS AT THIS POINT WE HAVE A DRY FORECAST GOING.
INTO EARLY NEXT WEEK A GRADUAL WARMING TREND IS FORECAST AS
RIDGING BUILDS EAST INTO THE WESTERN ROCKIES AND A TROUGH DEEPENS
INTO THE SOUTHEASTERN STATES. NORTHWEST FLOW ALOFT WILL USHER
ANOTHER DISTURBANCE ACROSS THE REGION LATE MONDAY INTO
TUESDAY...BUT THE MODELS LARGELY DISAGREE IN THE LOCATION OF THE
BEST FORCING...WILL KEEP THE INHERITED DRY FORECAST GOING FOR NOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1120 PM CST THU FEB 11 2016
MVFR/IFR/LOCAL LIFR CIGS AND FOG SHOULD SPREAD SLOWLY SOUTH AND
WEST OVERNIGHT AND THEN IMPROVE TO IFR/MVFR 18Z FRIDAY. A PATCH OF
VFR MAY DEVELOP FRIDAY AFTN ACROSS NCNTL NEB AS INDICATED BY THE
NAM AND RAP WHICH VARY WITH THE LOCATION BETWEEN KANW AND KLBF.
THE FORECAST USES THE NAM FOR THIS FEATURE WHICH KEEPS KLBF IN
MVFR ALL DAY.
CIGS SHOULD LOWER FRIDAY EVENING AS A WARM FRONT BEGINS TO MOVE
EAST THROUGH WRN NEB. THE FRONT MAY BE THE FOCUS FOR LIGHT SNOW
AND FREEZING DRIZZLE/FOG.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...ROBERG
SHORT TERM...ROBERG
LONG TERM...JACOBS
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1120 PM CST THU FEB 11 2016
.SYNOPSIS...
ISSUED AT 309 PM CST THU FEB 11 2016
THE SURFACE DATA AT 19Z SHOWED THE WARM FRONT ACROSS THE WESTERN
NEBRASKA SANDHILLS. THE EDGE OF CLOUDINESS WAS ACROSS CENTRAL AND
NORTH CENTRAL NEBRASKA. IN THE UPPER LEVELS...WATER VAPOR IMAGERY
INDICATED A POTENTIAL VORTICITY ANOMALY ALONG THE NEBRASKA-SOUTH
DAKOTA STATE LINE MOVING SOUTHEAST.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 309 PM CST THU FEB 11 2016
CLOUDS WILL INCREASE AGAIN LATE TONIGHT IN CENTRAL AND WESTERN
NEBRASKA. WEAK LIFT IN THE SATURATED ISOTHERMAL LAYER OVER CENTRAL
AND NORTHERN NEBRASKA WILL PRODUCE LIGHT FREEZING DRIZZLE LATE
TONIGHT AFTER MIDNIGHT. OTHERWISE...TONIGHT...THE WARM FRONT WILL
BACK THROUGH WESTERN AND SOUTHERN NEBRASKA BRINGING MODERATE NORTH
TO NORTHWEST WIND AND COLDER TEMPERATURES FRIDAY. WITH THE FRONT
STALLING ON THE PLAINS OF WYOMING AND COLORADO...CLOUDS WILL
PROBABLY HANG IN MOST OF THE DAY FRIDAY.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 309 PM CST THU FEB 11 2016
MID TERM...FRIDAY NIGHT THROUGH SUNDAY...IN THE MID RANGE
PERIOD...PRECIPITATION CHANCES AND FREEZING DRIZZLE POTENTIAL WILL
BE THE MAIN FORECAST CHALLENGE FOR LATE FRIDAY NIGHT INTO SATURDAY.
THIS WILL BE FOLLOWED BY THE THREAT FOR LIGHT SNOW ACROSS THE
SANDHILLS AND NORTHERN NEBRASKA SATURDAY NIGHT INTO SUNDAY. FOR
FRIDAY NIGHT...THE BOUNDARY LAYER ARCTIC FRONT WILL REMAIN ANCHORED
ACROSS THE PANHANDLE FRIDAY NIGHT INTO THE MORNING HOURS ON
SATURDAY. AT THE SAME TIME...A H750 WARM FRONT WILL BEGIN TO TRACK
EAST OF THE PANHANDLE...BECOMING ORIENTED ALONG A MERRIMAN TO NORTH
PLATTE LINE BY 12Z SATURDAY. LIFT WILL INCREASE INVOF...AND EAST OF
THE ELEVATED FRONT OVERNIGHT...LEADING TO INCREASED CHANCES FOR
LIGHT PRECIPITATION. EAST OF THE ELEVATED WARM FRONT...SNOW WILL BE
THE MAIN PTYPE...WHILE ALONG AND WEST OF THE FRONT...FREEZING
DRIZZLE WILL BE THE MAIN THREAT. WILL LEAVE THE FREEZING PTYPE
MENTION AS FZDZ FOR NOW AS THERE IS A DECENT DRY LAYER ABOVE THE
MOIST LAYER WHICH EXTENDS APPROXIMATELY FROM THE SFC TO 800MB. ON
SATURDAY...THIS ELEVATED WARM FRONT WILL CONTINUE TO TRACK EAST AND
WILL PUSH INTO CENTRAL AND EASTERN PORTIONS OF THE FORECAST AREA BY
00Z SUNDAY. HOWEVER...WITH THE EXCEPTION OF THE PANHANDLE AND FAR
WESTERN CWA...H850 TEMPS WILL REMAIN BELOW FREEZING. THIS WILL
FACILITATE AT LEAST A FZDZ MENTION INTO THE AFTERNOON HOURS. THIS
FREEZING DRIZZLE THREAT WILL BEGIN TO WANE DURING THE AFTERNOON
HOURS AS THE H750 FRONT STALLS ACROSS THE EASTERN CWA...AND ELEVATED
LIFT WEAKENS CONSIDERABLY. BY SATURDAY EVENING...A FAST MOVING MID
LEVEL DISTURBANCE WILL TRACK INTO THE WESTERN DAKOTAS...CLEARING THE
EASTERN DAKOTAS BY 12Z SUNDAY. LIGHT SNOW CONTINUES TO BE A THREAT
IN ASSOCIATION WITH THIS FEATURE...HOWEVER IT APPEARS AT THIS
TIME...IT WILL BE CONFINED TO THE NORTHERN THIRD OF THE FORECAST
AREA. QPF/S WILL BE VERY LIGHT AS THE BEST FORCING WILL RESIDE NORTH
OF THE FORECAST AREA OVER SOUTH DAKOTA.
LONG RANGE...SUNDAY NIGHT THROUGH THURSDAY...ON SUNDAY NIGHT...THE
GFS AND ECMWF HAVE A MID LEVEL DISTURBANCE TRACKING ACROSS COLORADO
INTO KANSAS. LOW POPS WERE PLACED IN THE FORECAST IN THE FAR SWRN
CORNER OF THE FORECAST AREA WHICH IS ON THE NORTHERN PERIPHERY OF
THE BEST LIFT...WHICH RESIDES OVER NWRN KS AND EAST CENTRAL
COLORADO. AFTER SUNDAY NIGHT...THE OVERALL PATTERN BEGINS TO FLATTEN
WITH A LOW AMPLITUDE RIDGE IN THE WEST AND LOW AMPLITUDE TROUGH IN
THE EAST. WEST NORTHWEST FLOW WILL RESIDE ACROSS THE FORECAST AREA
EARLY IN THE WEEK WITH A RIDGE BUILDING INTO THE CENTRAL CONUS BY
MIDWEEK NEXT WEEK. DRY CONDITIONS AND WARM TEMPERATURES ARE EXPECTED
WITH HIGHS GENERALLY IN THE 50S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1120 PM CST THU FEB 11 2016
MVFR/IFR/LOCAL LIFR CIGS AND FOG SHOULD SPREAD SLOWLY SOUTH AND
WEST OVERNIGHT AND THEN IMPROVE TO IFR/MVFR 18Z FRIDAY. A PATCH OF
VFR MAY DEVELOP FRIDAY AFTN ACROSS NCNTL NEB AS INDICATED BY THE
NAM AND RAP WHICH VARY WITH THE LOCATION BETWEEN KANW AND KLBF.
THE FORECAST USES THE NAM FOR THIS FEATURE WHICH KEEPS KLBF IN
MVFR ALL DAY.
CIGS SHOULD LOWER FRIDAY EVENING AS A WARM FRONT BEGINS TO MOVE
EAST THROUGH WRN NEB. THE FRONT MAY BE THE FOCUS FOR LIGHT SNOW
AND FREEZING DRIZZLE/FOG.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SPRINGER
SHORT TERM...SPRINGER
LONG TERM...BUTTLER
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS MEDFORD OR
931 PM PST THU FEB 11 2016
.DISCUSSION...AN UPDATE HAS BEEN MADE TO THE FORECASTS OF THE
PROBABILITY OF PRECIPITATION AND PRECIPITATION QUANTITY TONIGHT
THROUGH FRIDAY. A WEAK COLD FRONT IS OFFSHORE AND WILL TRACK
EAST AND DISSIPATE THROUGH FRIDAY. THERE IS A HIGH PROBABILITY OF
LIGHT RAIN NEAR THE COAST AND OVER THE COASTAL RANGE...TAPERING TO
CHANCE TO LIKELY POPS IN THE REMAINDER OF SOUTHWEST OREGON AND A
SLIGHT CHANCE FOR MUCH OF KLAMATH COUNTY AND CENTRAL SISKIYOU
COUNTY. WITH A SHALLOW MOIST LAYER, THIS WILL BE A LIGHT DRIZZLY
RAIN WHERE IT DOES RAIN INLAND. DESPITE THE CLOUD
COVER...TEMPERATURES WILL REMAIN WELL ABOVE NORMAL ON FRIDAY.
TEMPERATURES WILL BE A BIT COOLER...AROUND NORMAL ON SATURDAY.
THE NEXT SYSTEM WILL HAVE ITS FOCUS NORTH OF OUR AREA BUT THE GFS
CONTINUES TO INDICATE IT WILL BRING LIGHT RAIN NORTH OF THE UMPQUA
DIVIDE SATURDAY NIGHT THROUGH SUNDAY WITH THE PROBABILITY
DIMINISHING AS ONE TRAVELS FARTHER TO THE SOUTH AND EAST.
HIGH PRESSURE LOOKS TO BUILD SUNDAY NIGHT INTO TUESDAY NIGHT. THE
TIMING...STRENGTH AND POSITION OF THE NEXT TROUGH ARE STILL IN
QUESTION BUT THERE HAS BEEN CONSISTENCY IN INDICATING A CHANGE IN
THE PATTERN AND THE ARRIVAL OF A STRONGER SYSTEM AT MID-WEEK. THE
00Z GFS HAS TRENDED FARTHER SOUTH WITH A FOCUS OF PRECIPITATION
FROM AROUND MT SHASTA SOUTHWARD TO CENTRAL CALIFORNIA.
&&
.AVIATION...FOR THE 12/00Z TAF CYCLE... VFR CONDITIONS WILL PREVAIL
INTO TONIGHT. AREAS OF MVFR CIGS/VSBYS IN LIGHT RAIN WILL DEVELOP
ALONG THE COAST LATE TONIGHT AND SPREAD INLAND TO THE CASCADES DURING
THE DAY FRIDAY WITH AREAS OF HIGHER TERRAIN BECOMING OBSCURED.
-JRS
&&
.MARINE...UPDATED 900 PM PST THU FEB 11 2016...MIXED HIGH WEST
SWELL AT 19 TO 20 SECONDS AND MODERATE SOUTHWEST SWELL AT 10 TO 11
SECONDS WILL STEEPEN AND INCREASE INTO FRIDAY MORNING WITH THE
PERIOD BECOMING 17 TO 18 SECONDS. SEAS WILL THEN REMAIN WESTERLY
WITH A GRADUALLY DIMINISHING PERIOD THROUGH SUNDAY. COMBINED SEAS
WILL BUILD TO 13 TO 14 FEET THROUGH FRIDAY MORNING...SUBSIDE TO 12
FEET FRIDAY AFTERNOON THROUGH SATURDAY...REBUILD TO 12 TO 13 FEET
SATURDAY NIGHT...THEN SUBSIDE BELOW 10 FEET SUNDAY AFTERNOON. A
WEAK COLD FRONT WILL MOVE ONSHORE FRIDAY MORNING...AND THIS WILL
BRING SMALL CRAFT WINDS TO THE NORTHERN OUTER WATERS TONIGHT.
OFFSHORE HIGH PRESSURE WILL BUILD FRIDAY...THEN WEAKEN SATURDAY. A
SLIGHTLY STRONGER COLD FRONT WILL MOVE ONSHORE SATURDAY NIGHT.
OFFSHORE HIGH PRESSURE WILL REBUILD SUNDAY...THEN WEAKEN TUESDAY
AS A STRONGER FRONT APPROACHES THE AREA. -JRS
&&
.PREV DISCUSSION... /ISSUED 241 PM PST THU FEB 11 2016/
DISCUSSION...SKIES ARE THINNING OUT IN THE WAKE OF THE WEAK
SHORTWAVE THAT MOVED THROUGH THE AREA THIS MORNING. THIS IS IN
RESPONSE TO AN UPPER RIDGE BUILDING AHEAD OF A DEEPENING TROUGH NEAR
35N/140W. THIS SHOULD SLOW DOWN THE EASTWARD PROGRESSION OF THE
FRONT LATE TONIGHT. CURRENT HRRR MODEL SUGGEST THIS AND IS IN LINE
WITH THE NAM AND GFS. THEREFORE HAVE ADJUSTED POPS DOWN FOR THIS
EVENING AND TONIGHT, KEEPING THE BEST CHANCE FOR ANY RAIN OVER THE
MARINE WATERS AND ALONG THE COAST, NORTH OF CAPE BLANCO. I DON`T
THINK RAINFALL WILL MAKE MUCH IF ANY PROGRESS INLAND TONIGHT, BUT
STILL KEPT IN A SLIGHT CHANCE TO CHANCE ALONG THE SOUTH COAST AND IN
PORTIONS OF COOS AND NORTHWEST DOUGLAS COUNTY. SKIES SHOULD REMAIN
MOSTLY CLEAR THROUGH THIS EVENING BEFORE INCREASING AHEAD OF THE
COLD FRONT TONIGHT.
THE COLD FRONT WILL REACH THE COAST FRIDAY MORNING, THEN MOVING
ONSHORE DURING THE DAY FRIDAY. THIS WILL BRING THE BEST CHANCE FOR
MEASURABLE RAIN WITH MOST OF THE RAIN CENTERED ALONG THE COASTAL
MOUNTAINS AND CASCADES. EVEN THEN, QPF AMOUNTS ARE NOT EXPECTED TO
BE SIGNIFICANT AND MODELS HAVE BEEN TRENDING LOWER WITH QPF AMOUNTS.
SNOW LEVELS WILL LOWER ON FRIDAY, BUT WILL REMAIN ABOVE ALL THE
PASSES THROUGH FRIDAY.
A MOIST WESTERLY FLOW WILL SET UP FRIDAY NIGHT WITH A WEAK SHORT
WAVE MOVING THROUGH. MOST SHOWERS ARE EXPECTED TO REMAIN ALONG AND
WEST OF THE CASCADES, BUT THEY ARE EXPECTED TO BE LIGHT WITH SNOW
LEVELS BETWEEN 4500 AND 5000 FEET. THEREFORE WERE NOT EXPECTING
MUCH, IF ANY IMPACT ON ANY OF THE ROADS IN THE CASCADES.
500 MB HEIGHTS INCREASE SOME AS WEAK RIDGING BUILDS INTO THE AREA
SATURDAY. CONDITIONS SHOULD BE DRY DURING THE DAY, THEN A WARM FRONT
WILL ARRIVE SATURDAY NIGHT BRINGING STEADY LIGHT TO MODERATE
PRECIPITATION. THE BEST CHANCE FOR HEAVIER PRECIPITATION WILL BE IN
THE NORTHERN PART OF THE AREA SATURDAY EVENING, THEN THE FOCUS WILL
SHIFT SOUTH SATURDAY NIGHT THROUGH SUNDAY. SNOW LEVELS SATURDAY NIGHT
WILL INCREASE AND LIKELY BE ABOVE ALL THE PASSES THROUGH SUNDAY.
THE UPPER RIDGE WILL BUILD BACK INTO THE AREA SUNDAY NIGHT WITH
RAIN DECREASING, THEN ENDING FROM SOUTH TO NORTH. -PETRUCELLI
LONG TERM DISCUSSION...MONDAY THROUGH THURSDAY. MODELS AND THE
ENSEMBLE PLOTS START IN REMARKABLY GOOD AGREEMENT MONDAY WITH AN
UPPER LEVEL RIDGE OVER THE WEST COAST SHUNTING SYSTEMS JUST TO THE
NORTH OF THE FORECAST AREA. IT IS NOT UNTIL WEDNESDAY MORNING THAT
THE MODEL PLOTS SHOW ANY SIGNIFICANT DIVERGENCE...BUT THE MAIN
DIFFERENCES ARE WITH TIMING OF THE SHIFTING OF THE UPPER LEVEL RIDGE
TO THE EAST. THE GFS IS SLIGHTLY FASTER ON WEDNESDAY BRINGING
PRECIPITATION ONTO THE COAST WEDNESDAY MORNING, WITH THE ECMWF
BRINGING IT IN IN THE AFTERNOON. FROM THERE THE OVERALL PATTERN OF
AN UPPER LEVEL TROUGH OVER THE WEST COAST REMAINS FOR ALL OF THE
PLOTS...BUT THAT IS THE ONLY AGREEMENT WITH PLOTS ALL OVER THE
PLACE WITH DEPTH AND PLACEMENT OF THESE UPPER TROUGHS. WITH THIS IN
MIND HAVE GONE WITH THE ENSEMBLE MEAN POPS FOR THE REMAINDER OF THE
EXTENDED FORECAST. -SVEN
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL
4 PM PST SUNDAY FOR PZZ350-356-370-376.
SMALL CRAFT ADVISORY UNTIL 4 AM PST FRIDAY FOR PZZ370.
$$
DW/MAP/JRS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
409 AM MST FRI FEB 12 2016
.SHORT TERM...VALID FOR TDY AND SAT...
A COUPLE OF SYSTEMS WILL IMPACT THE FORECAST AREA THROUGH THE
SHORT TERM. THE FIRST SYSTEM IS STARTING TO MAKE ITS WAY ACROSS
SOUTHWEST MONTANA AND APPROACHING OUR FAR WESTERN COUNTIES. RADAR
ECHOES ARE INCREASING BUT CLOUD BASES STILL REMAIN FAIRLY HIGH AS
NO PRECIP HAS BEEN REPORTED ACROSS THE LIVINGSTON AND BOZEMAN
AREAS. FURTHER EAST TOWARD THE DAKOTA BORDER...A COLD FRONT BACKED
ITS WAY INTO THAT AREA YESTERDAY AND HAS MADE ITS WAY WESTWARD
PAST BILLINGS EARLY THIS MORNING. SATELLITE IS SHOWING A LOW
STRATUS DECK FROM ABOUT MILES CITY EASTWARD BUT NO PRECIP NOR FOG
HAS BEEN REPORTED. THE HRRR MODEL BRINGS SOME VERY LIGHT SHOWER
ACTIVITY INTO OUR WESTERN AREAS THIS MORNING BUT IT DOESN`T MAKE
IT AS FAR EAST AS BILLINGS. HOWEVER...THE GFS AND ECMWF KEEP
SCATTERED AREAS OF PRECIP ACROSS OUR ENTIRE AREA TODAY WITH THE
BEST CHANCES ACROSS OUR WEST THIS MORNING AND EASTERN ZONES THIS
AFTERNOON AND EVENING. AS A RESULT...WE HAVE REMOVED PRECIP
CHANCES THIS MORNING ACROSS THE EAST AND LOWERED CHANCES JUST A
BIT ELSEWHERE. THERE WILL BE A LARGE CONTRAST WITH TEMPERATURES
TODAY WITH BAKER ONLY SEEING TEMPERATURES AROUND 30 WHILE
LIVINGSTON COULD SEE 50 DEGREES.
FOR SATURDAY...A MUCH STRONGER SYSTEM WITHIN A NORTHWEST FLOW
ALOFT MOVES SOUTHEAST ACROSS OUR AREA DURING THE DAY AND LINGERING
ACROSS OUR FAR EASTERN COUNTIES INTO TONIGHT. WE WILL CONTINUE
WITH A HIGH POP CHANCE ACROSS MOST AREAS THROUGH THE DAY WITH
LIKELY POPS ACROSS CUSTER AND FALLON COUNTIES INTO TONIGHT.
SOUNDINGS FROM MILES CITY TO EKALAKA AND POINTS EAST SHOW THE
POSSIBILITY OF SOME LIGHT FREEZING RAIN AFTER MIDNIGHT TONIGHT SO
AREA ROADS MAY BE SLICK. TEMPERATURES SATURDAY WILL WARM BACK INTO
THE 50S...WITH 40S ALONG THE DAKOTA BORDERS. HOOLEY
.LONG TERM...VALID FOR SUN...MON...TUE...WED...THU...
WARM AND ABOVE AVERAGE TEMPERATURES WILL CONTINUE THROUGH NEXT
WEEK AS A RIDGE OF HIGH PRESSURE TO OUR WEST IS STUBBORN TO ERODE.
NOT EXPECTING CONDITIONS TO BE AS WARM AS THIS PAST TUESDAY AND
WEDNESDAY...BUT TEMPERATURES WILL STILL BE IN THE UPPER 50S TO
NEAR 60 IN THE DOWNSLOPING NORTHWEST FLOW.
SEVERAL DISTURBANCES WILL PUSH THROUGH THE AREA DURING THE WEEK.
THE FIRST ONE WILL MOVE THROUGH MONDAY NIGHT THROUGH TUESDAY.
EXPECTING MOSTLY RAIN WITH THIS SYSTEM AS AIR AND GROUND
TEMPERATURES SHOULD STAY ABOVE FREEZING. PRETTY GOOD PRESSURE
RISES BEHIND THIS SYSTEM ALSO BRING ABOUT THE CHANCE FOR SOME
GUSTY CONDITIONS LATE MONDAY THROUGH TUESDAY AFTERNOON. THOUGH
WITH THE BEST PRESSURE RISES APPEARING TO MOVE THROUGH AT NIGHT
WILL NOT ISSUE ANY HIGHLIGHTS AT THIS TIME. IN ADDITION...STRONGEST
MID-LEVEL WINDS LOOK TO STAY MOSTLY WEST OF BILLINGS AND ROUNDUP.
A WEAK WAVE MOVES THROUGH WEDNESDAY BUT LITTLE MOISTURE AND UPPER
LEVEL FORCING SHOULD KEEP SHOWER CHANCES LOW. LAST SYSTEM
APPROACHES FROM THE SOUTHWEST TOWARDS THE LATER PART OF THE WEEK.
BETTER DYNAMICS WITH THIS SYSTEM ARE EXPECTED BUT THE SPLITTING
AND WEAKENING NATURE OF THIS SYSTEM SHOULD JUST ALLOW FOR A SLIGHT
CHANCE OF POPS IN THE PLAINS...WITH MOST OF THE WESTERN TERRAIN
SEEING ANY APPRECIABLE PRECIP. DOBBS
&&
.AVIATION...
MVFR CONDITIONS POSSIBLE AT ALL TERMINALS EXCEPT KSHR THROUGH 18Z
TOMORROW AS A DISTURBANCE SLIDES ACROSS THE AREA. MOSTLY RAIN IS
EXPECTED THOUGH SNOW SHOWERS ARE POSSIBLE AT KLVM...KMLS...AND
KBHK. MVFR CONDITIONS POSSIBLE AT KSHR FROM 18Z TO 00Z. CONDITIONS
BEGIN TO CLEAR OUT BY 21 TO 00Z TOMORROW FROM WEST TO EAST. DOBBS
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SAT SUN MON TUE WED THU
-------------------------------------------------------
BIL 045 034/052 033/054 038/058 041/059 038/060 037/055
3/W 13/W 23/W 24/W 22/W 11/E 11/E
LVM 055 037/048 034/049 040/055 045/056 041/056 036/052
3/W 04/W 35/W 34/W 32/W 11/N 22/W
HDN 045 029/053 031/054 034/058 037/059 034/060 034/054
3/W 14/W 23/W 24/W 32/W 11/E 11/E
MLS 038 026/050 029/052 033/054 037/054 034/055 033/053
2/W 46/W 21/B 23/W 22/W 11/E 11/E
4BQ 039 028/051 030/050 032/053 037/055 034/059 033/055
2/W 34/W 32/W 24/W 32/W 11/B 11/E
BHK 030 018/043 028/047 028/048 032/049 030/050 029/050
1/E 46/W 31/B 12/W 22/W 11/B 11/E
SHR 047 027/052 027/049 032/054 034/056 032/058 031/054
2/W 13/W 53/W 23/W 22/W 11/B 11/E
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
727 AM CST FRI FEB 12 2016
.SYNOPSIS...
ISSUED AT 320 AM CST FRI FEB 12 2016
ARCTIC HIGH PRESSURE CONTINUES TO BUILD SOUTH FROM THE DAKOTAS AND
MINNESOTA INTO NEBRASKA. AT 08Z...THE LEADING EDGE OF THE FRONT WAS
ANALYZED FROM NEAR PINE RIDGE SOUTH DAKOTA THROUGH NORTH PLATTE THEN
SOUTHEAST ACROSS NCTRL KS. A LARGE AREA OF STRATUS EXTENDS NORTH AND
EAST OF THE FRONT. NO INDICATION YET OF FOG DEVELOPMENT IN WESTERN
NEBRASKA. THE RAP AND HRRR MODELS BOTH SUGGEST DEVELOPMENT NEAR THE
WESTERN EDGE OF THE STRATUS ALONG ADVANCING COLD FRONT IN THE
WESTERN SANDHILLS INTO SOUTHWEST NEBRASKA THIS MORNING. TEMPERATURES
RANGING FROM 26 TO 32 ACROSS WESTERN NEBRASKA...WITH COLDER TEENS
REPORTED IN EASTERN SOUTH DAKOTA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CST FRI FEB 12 2016
THE MAIN FORECAST CONCERNS WILL BE THE BACKDOOR COLD FRONT FORECAST
TO PUSH INTO THE WESTERN NEBRASKA PANHANDLE AND NORTHEAST COLORADO
BY LATE THIS AFTERNOON AND ITS EFFECTS ON HIGH TEMPERATURES ACROSS
WESTERN NEBRASKA TODAY. ONLY MINOR ADJUSTMENTS TO HIGHS TODAY. NEAR
38 IN THE SWRN TIER OF COUNTIES IN CLOSER PROXIMITY TO THE FRONT.
LOWER 20S IN BOYD AND NERN HOLT COUNTY WHERE TEMPERATURES WILL
ACTUALLY HOLD STEADY THROUGH THE DAY FROM THIS MORNINGS LOWS.
FOR TONIGHT...A WARM FRONT WILL BEGIN TO PUSH EAST INTO WESTERN
NEBRASKA. WITH WIDESPREAD STRATUS ALREADY IN PLACE...CONDITIONS WILL
BE FAVORABLE FOR PATCHY FREEZING DRIZZLE TO BEGIN DEVELOPING DUE TO
A LACK OF ICE CRYSTALS INTRODUCED FROM ALOFT. THE PATCHY FREEZING
DRIZZLE FORECAST TO BEGIN LATE THIS EVENING MAINLY WEST OF A LINE
FROM GORDON THROUGH NORTH PLATTE...ADVANCING FURTHER EAST TO NEAR
VALENTINE THROUGH BROKEN BOW BY LATE TONIGHT. WHERE SOME SATURATION
DOES EXIST UP INTO THE DENDRITIC LAYER...A 20 TO 30 PERCENT CHANCE
FOR LIGHT SNOW ACROSS THE EASTERN TWO THIRDS OF THE FORECAST AREA.
THERE WILL BE AN AREA IN BETWEEN WHERE FREEZING DRIZZLE AND LIGHT
SNOW MAY BOTH OCCUR...MAINLY ACROSS WESTERN CHERRY COUNTY SOUTH
THROUGH THE CENTRAL SANDHILLS INTO SOUTHWESTERN NEBRASKA. SINCE ONLY
A SMALL AMOUNT OF FREEZING DRIZZLE CAN IMPACT TRAVEL...WILL CONTINUE
TO HIGHLIGHT THE POTENTIAL FOR THE LIGHT FREEZING DRIZZLE TONIGHT
INTO SATURDAY MORNING IN A SPECIAL WEATHER STATEMENT AND THE
HAZARDOUS WEATHER OUTLOOK.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 320 AM CST FRI FEB 12 2016
12Z SATURDAY AND BEYOND. SATURDAY WILL BE ANOTHER TRANSITION DAY AS
AN ELEVATED WARM FRONT LIFTS EAST ACROSS THE SANDHILLS.
HOWEVER...OUTSIDE OF THE EASTERN PANHANDLE AND WESTERN
SANDHILLS...ALL OTHER LOCATIONS WILL CONTINUE TO SEE TEMPERATURES
BELOW FREEZING. THIS WILL FACILITATE A CONTINUED MENTION
OF FREEZING DRIZZLE INTO THE EARLY AFTERNOON AS SOUNDINGS
INDICATE SATURATION BELOW THE DGZ WHERE THERE/S WEAK OMEGA. WHERE
SUFFICIENT SATURATION IS SHOWN IS ACROSS OUR NORTHEASTERN ZONES
WHERE LIGHT SNOW IS FORECAST. THE MODELS ONLY SUGGEST A FEW
HUNDRETHS AT MOST QPF...AND WITH VERY WEAK LIFT SEEN...SNOW
ACCUMULATIONS SHOULD ONLY AMOUNT TO A FEW TENTHS AT BEST.
ADDITIONAL SNOW CHANCES ARE POSSIBLE ACROSS OUR FAR NORTHERN
ZONES SATURDAY EVENING INTO EARLY SUNDAY AS A FAST MOVING MID-
LEVEL DISTURBANCE DROPS SOUTHEAST ACROSS THE DAKOTAS. THE MODELS
CONTINUE TO INDICATE THE BEST FORCING AND MOISTURE NORTH OF THE
BORDER ACROSS THE DAKOTAS...SO ONLY A FEW TENTHS ADDITIONAL SNOW
ACCUMULATIONS ARE EXPECTED.
WARMING TEMPERATURES ARE FORECAST FOR SUNDAY AS H85 T/S ARE SHOWN TO
CLIMB BACK ABOVE 0C FOR THE ENTIRE CWA. HIGHS IN THE 40S ARE
FORECAST. SUNDAY EVENING...THE MODELS DEPICT A FAST MOVING MID-
LEVEL DISTURBANCE DROPPING SOUTHEAST ACROSS THE HIGH PLAINS
OF COLORADO INTO WESTERN KANSAS. AT THIS POINT...FORCING IS TOO
WEAK WITHIN THE CWA FOR PRECIPITATION...BUT THE 00Z MODELS HAVE
TRENDED SLIGHTLY EAST WITH THE PROJECTED QPF. WILL NEED TO
MONITOR CLOSELY AS AT THIS POINT WE HAVE A DRY FORECAST GOING.
INTO EARLY NEXT WEEK A GRADUAL WARMING TREND IS FORECAST AS
RIDGING BUILDS EAST INTO THE WESTERN ROCKIES AND A TROUGH DEEPENS
INTO THE SOUTHEASTERN STATES. NORTHWEST FLOW ALOFT WILL USHER
ANOTHER DISTURBANCE ACROSS THE REGION LATE MONDAY INTO
TUESDAY...BUT THE MODELS LARGELY DISAGREE IN THE LOCATION OF THE
BEST FORCING...WILL KEEP THE INHERITED DRY FORECAST GOING FOR NOW.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 726 AM CST FRI FEB 12 2016
CURRENT IFR CEILINGS WITH VSBY BTWN 1 AND 3SM AT KVTN FCST TO
IMPROVE TO P6SM OVC009 AFTER 15Z...THEN MVFR AFTER 17Z. AFTER
06Z/13TH A TEMPO ADDED FOR LIGHT SNOW. AT KLBF MVFR CEILING FCST
TODAY. FOR TONIGHT...IFR CEILINGS AFTER 03Z WITH THE POSSIBILITY
FOR PATCHY FZDZ. DID NOT INCLUDE IN TAF ATTM AS CONFIDENCE AND
COVERAGE TOO LOW TO INCLUDE.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...ROBERG
SHORT TERM...ROBERG
LONG TERM...JACOBS
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS PORTLAND OR
301 AM PST FRI FEB 12 2016
.SYNOPSIS...A DECENT PACIFIC COLD FRONT WILL MOVE ONTO THE COAST MID
MORNING TODAY AND MOVE ACROSS THE REMAINDER OF SOUTHWEST WASHINGTON
AND NORTHWEST OREGON TODAY FOR A DECENT SHOT OF RAIN. SNOW LEVELS
WILL FALL BELOW THE CASCADE PASSES TONIGHT AS AN AREA OF SHOWERS
ASSOCIATED WITH THE ASSOCIATED UPPER TROUGH MOVES THROUGH WESTERN
WASHINGTON AND CLIPS THE NORTH PART OF OUR FORECAST AREA. A WARM
FRONT WILL BRING INCREASING RAIN TO THE NORTH PART OF THE AREA
SATURDAY AFTERNOON AND ALL OF SOUTHWEST WASHINGTON AND NORTHWEST
OREGON SATURDAY NIGHT AND SUNDAY. THE RAIN WILL BE HEAVY AT TIMES
SATURDAY NIGHT AS THE FIRST STRONGER WAVE ALONG THE WARM FRONT MOVES
THROUGH...FOLLOWED BY A SECOND WEAKER WAVE ON SUNDAY. THE WARM FRONT
WILL LIFT NORTH INTO WESTERN WASHINGTON SUNDAY NIGHT AND MONDAY WITH
RAIN DECREASING FROM THE SOUTH. ADDITIONAL UNSETTLED WEATHER WILL
PRODUCE MORE VALLEY RAIN AND MOUNTAIN SNOW THE MIDDLE AND LATTER
PARTS OF NEXT WEEK.
&&
.SHORT TERM...THE WARM FRONT WITH THE SYSTEM OFF THE COAST BROUGHT
SOME RAIN TO SOUTHWEST WASHINGTON AND NORTHWEST OREGON FRIDAY
AFTERNOON AND EVENING. THE COLDER CLOUD TOPS ASSOCIATED WITH THE
COLD FRONT SEPARATED FROM THE LOW LEVEL FRONT AND BROUGHT A PERIOD
OF DECENT RAIN TO THE COAST OVERNIGHT. THE MAIN LOW LEVEL COLD FRONT
IS STILL OFFSHORE EARLY THIS MORNING AND WILL MOVE ONSHORE MID
MORNING TODAY WITH ONE MORE SHOT OF RAIN AS IT MOVES THROUGH THE
INLAND AREAS TODAY. THE FRONT WILL BE EAST OF THE CASCADES BY MID
AFTERNOON.
THE ASSOCIATED COOL UPPER TROUGH IS OFFSHORE THIS MORNING...AND WILL
MOVE THROUGH WESTERN WASHINGTON AND FAR NORTHERN OREGON TONIGHT FOR
SOME SHOWERS. SNOW LEVELS WILL FALL BELOW THE CASCADE PASSES
TONIGHT...BUT SNOW AMOUNTS WILL LIKELY STAY BELOW ADVISORY CRITERIA.
THERE IS A SLIGHT CHANCE OF THUNDER OVER THE NORTHERN COASTAL WATERS
LATE TODAY AND TONIGHT...AND NEAR THE NORTH COASTAL ZONES TONIGHT.
ATTENTION WILL THEN TURN TO THE SYSTEM NOW APPROACHING 150W. THE
WARM FRONT FROM THIS SYSTEM WILL SPREAD INTO SOUTHWEST WASHINGTON
AND NORTHWEST OREGON SATURDAY AFTERNOON AND BE OVER THE ENTIRE AREA
SATURDAY NIGHT AND SUNDAY. THE FIRST WAVE RIDING ALONG THE WARM
FRONT WILL MOVE THROUGH SATURDAY NIGHT. THIS WAVE LOOKS FAIRLY
STRONG...MAY PRODUCE GALE FORCE WINDS OVER THE COASTAL WATERS...AND
LOCALLY HEAVY RAIN OVER SOUTHWEST WASHINGTON AND NORTHWEST OREGON. A
SECOND WEAKER WAVE WILL KEEP THE RAIN GOING ON SUNDAY. SNOW LEVELS
WILL INITIALLY BE AROUND THE PASSES LATE SATURDAY AND A GOOD PART OF
SATURDAY NIGHT BEFORE RISING WELL ABOVE THE PASSES SUNDAY. GIVEN THE
MODEL QPF...THERE APPEARS A GOOD CHANCE THAT PORTIONS OF THE SOUTH
WASHINGTON CASCADES AND PERHAPS THE NORTH OREGON CASCADES ABOVE 4000-
5000 FT WILL SEE ENOUGH SNOW...SOMEWHERE ON THE ORDER OF 4 TO 8
INCHES...TO REQUIRE A SNOW ADVISORY SATURDAY NIGHT BEFORE THE SNOW
LEVEL RISES.
THE RAIN SHOULD DECREASE FROM THE SOUTH EITHER LATE SUNDAY OR SUNDAY
NIGHT AS THE WAR FRONT LIFTS NORTH. TOLLESON
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
SUNDAY NIGHT THROUGH THURSDAY...THE PROGRESSIVE WEATHER PATTERN WILL
PERSIST INTO NEXT WEEK. MODELS CONTINUE TO SHOW A FLAT UPPER LEVEL
RIDGE MOVING OVER THE PAC NW EARLY NEXT WEEK. THIS COULD BRING A
BRIEF BREAK FROM THE RAIN MONDAY...BUT WILL MAINTAIN SOME CHANCE POPS
IN THE FORECAST DUE TO LINGERING INSTABILITY. A WEAK SHORTWAVE
DISTURBANCE LOOKS TO RIDE OVER THE TOP OF THE RIDGE ON TUESDAY AND
WILL LIKELY PUSH ANOTHER FRONT ACROSS THE REGION LATE TUESDAY/EARLY
WEDNESDAY BRINGING MORE RAIN. CASCADE SNOW LOOKS TO RETURN WEDNESDAY
AFTERNOON WITH SNOW LEVELS LOWERING TO AROUND 3500 FT. UNSETTLED
WEATHER AND LOWERING SNOW LEVELS CONTINUE INTO THURSDAY AS THE BASE
OF THE TROUGH MOVES ACROSS THE FORECAST AREA. MONDAY WILL LIKELY BE
THE WARMEST DAY...WITH TEMPS TRENDING COOLER EARLY NEXT WEEK. /64
&&
.AVIATION...A VERY MIXED BAG IN TERMS OF CONDITIONS AT THIS HOUR. FOG
AND LOW CLOUDS HAVE HUNG AROUND THE WILLAMETTE VALLEY AND NORTH TO
INCLUDE THE TUALATIN VALLEY AS WELL. AS SUCH HAVE SEEN VLIFR CONDS AT
KEUG...KSLE...AND KHIO AT TIMES BUT WITH PERIODIC IMPROVEMENTS TO
JUST STRAIGHT IFR CIGS/VSBYS. HAVE SEEN CIGS AT KPDX EVEN BE RATHER
INCONSISTENT AS A MVFR DECK HAS WAVERED BETWEEN 1500 FEET AGL AND NON
EXISTENT. GIVEN THE STRATUS/FOG DECK IS RATHER NEBULOUS AND MODEL/MOS
GUIDANCE IS FAR LESS THAN HELPFUL..HAVE VERY LOW CONFIDENCE FOR MOST
OF THE INLAND TAFS COVERING THE NEXT SEVERAL HOURS. COASTAL TERMINALS
SAW A DECENT BREAK IN THE LOW CLOUDS AND FOG...HOWEVER...THERE IS
JUST ENOUGH ONSHORE FLOW TO PUSH THE MARINE DECK ONSHORE. WILL LIKELY
SEE THE COASTAL TERMINALS REMAIN IFR WITH CIGS 007-010 THROUGH AT
LEAST 21Z. IN GENERAL...GUIDANCE INDICATES CONDS IMPROVING TO VFR
SOMETIME AT OR AFTER 13/00Z.
KPDX AND APPROACHES...LOW CONFIDENCE IN THE FORECAST AS CIGS REMAIN
HIGHLY VARIABLE. THE MVFR 016 AGL CIGS CURRENTLY IN PLACE SHOW LITTLE
SIGN OF MOVING ALTHOUGH GORGE OUTFLOW WINDS ARE PROBABLY KEEPING THEM
FORM DROPPING LOWER. WEB CAMS OF DOWNTOWN PORTLAND SHOW SOME LOWER
CLOUDS BANKING UP AGAINST THE WEST HILLS. SHOULD THE WINDS EASE
BEFORE 18Z OR SO...MAY SEE SOME IFR CIGS QUICKLY DRIFT OVER THE FIELD
THIS MORNING. OTHERWISE...EXPECT THE CIGS TO LIFT BECMG VFR AFT 21Z.
/JBONK
&&
.MARINE...WINDS HAVE BEEN VERY SLOW TO INCREASE TONIGHT AND HAVE JUST
RECENTLY SEEN GUSTS CLIMB REACHING 20-25 KT. DECIDED TO EXTEND THE
SCA FOR WINDS THROUGH 8 AM THIS MORNING BASED ON LOOSELY BETTER
PERFORMANCE OUT OF THE HRRR MODEL THUS FAR AND IT`S TIMING OF
DROPPING WINDS BELOW CRITERIA THEN. STILL...THIS REMAINS A VERY
MARGINAL WIND EVENT. LONG PERIOD SWELL CONTINUES TO BUILD THIS
MORNING AND SHOULD BE PEAKING IN THE 13-15 FT RANGE SHORTLY.
NEXT EVENT OF NOTE WILL BE A THREAT FOR LOW END GALE GUSTS SATURDAY
NIGHT. MODELS HAVE CONTINUED TO BACK OFF ON THE WIND SPEEDS OVER THE
LAST 48 HOURS. STILL HAVE LOW END GALE GUSTS IN THE FORECAST FOR THE
TIME BEING. OPTED TO HOLD OFF ISSUING A WATCH AS THE DECREASING TREND
WOULD GIVE ANOTHER 12 HOURS WORTH OF MODEL RUNS TO SEE THOSE GUSTS
FALL BACK TOWARD THE LOWER 30 KT RANGE AND THUS OUT OF GALE CRITERIA.
SURFACE PRESSURE FEATURES THEREAFTER REMAIN HIGHLY VARIABLE IN
LOCATION AND TIMING. THE TREND...THOUGH... IS FOR SEAS TO FALL BELOW
10 FT SUNDAY EVENING WITH WINDS BECOMING LESS AND LESS EVENTFUL.
/JBONK
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 8 AM PST THIS MORNING
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR
OUT 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 AM PST
SUNDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL
4 AM PST SATURDAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1001 AM EST FRI FEB 12 2016
.SYNOPSIS...
A FAST MOVING UPPER LEVEL DISTURBANCE WILL BRING A BRIEF CHANCE OF
PRECIPITATION TO MUCH OF THE AREA TODAY. A STRONG DOME OF CANADIAN
HIGH PRESSURE WILL SETTLE IN OVER THE WEEKEND...USHERING IN ANOTHER
PERIOD OF COLD TEMPERATURES. THIS WILL BE FOLLOWED BY ANOTHER
WEATHER SYSTEM WHICH WILL PRODUCE A BETTER CHANCE OF PRECIPITATION
EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
1500 UTC UPDATE...POPS HAVE BEEN ADJUSTED TO ACCOUNT FOR LIGHT SNOW
MOVING ACROSS UPSTATE NC. WINDS WERE UPDATED TO INCLUDE THE LATEST
NAM GUIDANCE...WITH GUSTS INCREASING AT HIGHER MC MOUNTAIN ELEVATIONS
LATER TODAY. ONLY MINOR ADJUSTMENTS WERE MADE TO MAXIMUM
TEMPERATURES.
AS OF 650 AM...THE MODELS SEEM TO BE LATCHING ONTO MORE MOISTURE OR
BETTER LLVL LIFT EAST OF THE MTNS. THE 6Z GFS AND THE LATEST RAP AND
HRRR NOW HAVE HIGHER POP/MORE COVERAGE OF SNOW SHOWERS ACROSS THE
PIEDMONT. IT LOOKS LIKE A BAND MAY SET UP SOMEWHERE ACROSS THE
UPSTATE. HOWEVER...CONFIDENCE IS STILL LOW. POPS MAY NEED TO BE
ADJUSTED UPWARD IF TRENDS ON RADAR LOOK TO BE LINING UP WITH THE
HRRR. OTHERWISE...FCST LOOKS ON TRACK.
AS OF 315 AM...A VIGOROUS SHORT WAVE CAN BE SEEN ON WATER VAPOR
IMAGERY DIVING INTO THE OHIO VALLEY TOWARD THE BASE OF A LONG WAVE
TROF ALONG THE EAST COAST. THIS WAVE WILL CROSS THE CWFA JUST AFTER
DAYBREAK...AND WILL BE ACCOMPANIED BY A 130 KT 300 MB JET. THIS WILL
RESULT IN STRONG MID AND UPPER LEVEL FORCING FROM ABOUT 12Z TO 18Z
TODAY. AT THE SFC...A WEAK ALBERTA CLIPPER WAS ANALYZED OVER
MO...AND WILL STREAK JUST SOUTH OF THE CWFA DURING THE DAY. LLVL FLOW
IS BACKING OUT OF THE WSW...BUT STRUGGLING TO TAP INTO MUCH MOISTURE.
SO THE FORECAST CHALLENGE FOR TODAY WILL BE HOW MUCH QPF WILL
ACCOMPANY THE SYSTEM...AS THE OP MODELS SHOW SOME SPREAD ON COVERAGE
AND AMOUNTS. THE 00Z NAM KEEPS THE PIEDMONT DRY...WHILE THE
OTHER OP MODELS HAVE SOME LIGHT AMOUNTS. I LIKE THE AGREEMENT OF THE
CAMS ON THE SIMULATED REFLECTIVITY...SHOWING LIGHT PRECIP BREAKING
OUT ACRS THE MTNS RIGHT AROUND DAYBREAK...THEN QUICKLY SPREADING
EAST ACROSS THE PIEDMONT DURING THE LATE MORNING HOURS. BY EARLY
AFTN...THE MODELS SHOW PRECIP CONFINED TO WESTERLY UPSLOPE AREAS
ALONG THE TN BORDER. I THINK MUCH OF WHAT THE CAMS ARE SHOWING WOULD
BE VIRGA...GIVEN THE MOISTURE MAINLY IN THE MID LEVELS. SO POPS SHOW
LIKELY IN THE MTNS...ESP NEAR THE TN BORDER...WHILE ONLY SLIGHT
CHANCE TO LOW-END CHANCE EAST. FCST PROFILES SHOW THAT THIS WOULD BE
A RAIN/SNOW EVENT...WITH WET-BULB EFFECTS ALLOWING FOR LIGHT SNOW
SHOWERS AND/OR FLURRIES JUST ABOUT ANYWHERE THIS MORNING. ACCUMS
THRU THE DAY WILL BE IN THE MTNS...WITH NOTHING MORE THAN A DUSTING
EXPECTED ELSEWHERE. TEMPS SHOULD BE ABOUT 10-15 DEGREES BELOW NORMAL
UNDER MOSTLY CLOUDY SKIES AND SPOTTY PRECIP.
TONIGHT...THE CLIPPER SYSTEM WILL ALREADY BE DEVELOPING A NEW LOW
OUT OVER THE ATLANTIC JUST EAST OF THE OUTER BANKS BY EARLY
EVENING...WHILE A STRONG ARCTIC HIGH (PRESSURE AROUND 1044 MB)
BUILDS IN ACROSS THE PLAINS TO THE SOUTHEAST STATES. THE SFC
PRESSURE GRADIENT NEVER GETS THAT IMPRESSIVE ATOP THE CWFA.
HOWEVER...THE 850 MB FLOW RAMPS UP OUT OF THE NW TO 40-55 KT ACROSS
THE NC MTNS WITH VERY STRONG CAA. THIS WILL RESULT IN A DOWN RIGHT
COLD AND BLUSTERY NIGHT IN THE MTNS...WITH THE ADDITION OF LINGERING
MOISTURE FOR NW FLOW SNOW SHOWERS. IN FACT...THE COLD AIR AND NEAR
PERFECT ORTHOGOTHAL DIRECTION COULD MAKE FOR EFFICIENT SNOW
PRODUCING SHOWERS ALONG THE TN LINE. THE EXPECTED SNOW WITH THE
CLIPPER ALONG WITH THE NW FLOW SNOW SHOULD RESULT IN TOTAL ACCUMS OF
2-4" ACROSS THE USUAL NW FLOW UPSLOPE AREAS. THIS ALONG WITH WINDS
IN THE 25-40 MPH RANGE AND GUSTS IN THE 40-55 MPH RANGE SEEMS TO
WARRANT A WINTER WEATHER ADVISORY. I WILL START IT AT NOON TO
EMCOMPASS THE SNOW ACCUMS EXPECTED TODAY...AND GO THRU 6 AM SATURDAY
(WHEN SNOW SHOWER ACTIVITY WILL TAPER OFF). IN ADDITION...TEMPS WILL
BE PLUMMETING INTO THE TEENS TO SINGLE DIGITS...SO WIND CHILLS WILL
BE IN THE -5 TO -15 F RANGE FOR MOST LOCATIONS ABOVE 3500 FT. A WIND
CHILL ADVISORY WILL BE ISSUED STARTING AT MIDNIGHT...ALTHOUGH SOME
LOCATIONS ABOVE 5000 FT OR SO MAY START SEEING DANGEROUS WIND CHILLS
EARLIER IN THE EVENING. THE REST OF THE CWFA SHOULD SEE CLEARING
SKIES AND LINGERING WINDS WITH CHILLY TEMPS ABOUT 8-15 DEGREES BELOW
NORMAL.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
AS OF 300 AM EST FRIDAY...A BROAD TROUGH OF LOW PRESSURE WILL EXTEND
SOUTHWARD ACROSS THE EASTERN UNITED STATES SATURDAY FROM A LOW
CENTER OVER SOUTHERN QUEBEC. ISOLATED TO SCATTERED NW FLOW SNOW
SHOWERS COULD LINGER ACROSS THE NORTHERN MOUNTAINS EARLY
SATURDAY...BUT WITH MOISTURE DIMINISHING THROUGH THE DAY. COLD
MORNING TEMPERATURES AND BRISK NW FLOW WILL PERMIT BITTER WIND
CHILLS TO CONTINUE THROUGH SATURDAY MORNING ACROSS THE
MOUNTAINS...AND ON INTO SATURDAY NIGHT/SUNDAY MORNING ACROSS THE
NORTHERN MOUNTAINS. MEANWHILE...VERY COLD AIR WILL DIVE SOUTHEAST
FROM CANADA INTO THE REGION ON THE BACK SIDE OF THE TROUGH AS THE
ASSOCIATED ARCTIC HIGH PRESSURE MOVES ACROSS THE MIDWEST ON SATURDAY
AND REACHES THE EASTERN SEABOARD BY LATE SUNDAY. IN THE COLD
AIRMASS...MAX TEMPERATURES WILL RUN AT LEAST 20 DEGREES BELOW CLIMO
IN MOST AREAS...WHILE SUNDAY MORNING MINS WILL BE 10 TO 20 DEGREES
BELOW CLIMO. A WIND CHILL ADVISORY WILL CONTINUE UNTIL MID SUNDAY
MORNING ACROSS THE NORTHERN NC MOUNTAINS.
THE UPPER FLOW WILL FLATTEN SLIGHTLY OVER THE EAST ON SUNDAY AS A
NORTHERN STREAM SHORTWAVE DIGS INTO THE MIDWEST WHILE A SOUTHERN
STREAM SYSTEM TAKES SHAPE FROM THE FOUR CORNERS REGION TOWARD TX.
THE FIRST HINT OF MID LEVEL UPGLIDE MOISTURE WILL ARRIVE IN THE CWA
FROM THE WEST ON SUNDAY...BUT WITH DRY LOW LEVELS PRECLUDING ANY
PRECIPITATION FROM REACHING THE GROUND THROUGH LATE DAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 300 AM EST FRIDAY...A WINTRY MIXED MAG OF PRECIPITATION IS
LOOKING LIKELY STARTING SUNDAY NIGHT INTO MONDAY GIVEN THE VERY COLD
AND DRY AIRMASS THAT WILL BE PRESENT OVER THE AREA BEFORE ONSET.
THERE IS GOOD MODEL CONSENSUS ON THE ENERGY WITH THE SOUTHERN STREAM
SYSTEM SHARPENING UP RAPIDLY OVER THE LOWER MS RIVER VALLEY SUNDAY
NIGHT INTO MONDAY. MEANWHILE...THE SURFACE HIGH CENTER TO THE NORTH
WILL RETREAT OFFSHORE. LOW LEVEL UPGLIDE MOISTURE WILL FILL IN
RAPIDLY ACROSS OUR AREA EARLY MONDAY...WITH THE 850 MB ZERO ISOTHERM
ALONG THE SOUTHERN FRINGE OF THE AREA AROUND DAYBREAK MOVING RAPIDLY
TOWARD THE NORTHERN FRINGE OF THE FORECAST AREA BY MID AFTERNOON.
EVEN THOUGH COLD AIR DAMMING IS VERY LIKELY...THE COLD AIR MAY ONLY
STAY DEEPLY ENTRENCHED EAST OF THE NORTHERN BLUE RIDGE GIVEN THE
INCREASINGLY OFFSHORE PARENT HIGH LOCATION. STILL...PROFILES ARE
PLENTY COLD FOR PRECIPITATION TO START AS SNOW THROUGHOUT BEFORE
DAYBREAK MONDAY...WITH A BLOSSOMING WARM NOSE THEN INVADING THE
SOUTHERN TIER OF THE FORECAST AREA MONDAY MORNING AND MOVING
NORTHWARD ACROSS THE REGION THROUGH THE DAY.
THE BEST UPPER FORCING ACTUALLY ARRIVES MONDAY NIGHT AS UPPER JET
DIVERGENCE BRIEFLY SETS UP AND DEEP LAYER Q VECTOR FORCING CROSSES
THE REGION AHEAD OF THE INCREASINGLY NEGATIVE TILT UPPER TROUGH.
FORCING AND MOISTURE WILL BE STRONGLY FOCUSED ON THE REGION LATE
MONDAY NIGHT/EARLY TUESDAY WITH THE SURFACE LOW CENTER LIKELY
TRACKING THROUGH THE CENTRAL CAROLINAS...THE CAD GETTING FURTHER
PINCHED OFF TO THE NORTH...AND THE HEAVIEST PRECIPITATION DURING THE
WARMEST PART OF THE EPISODE.
SO...THERE ARE PLENTY OF POTENTIAL HAZARDS. SIGNIFICANT ICE AND SNOW
ACCUMULATIONS WILL BE POSSIBLE...MAINLY OVER WESTERN NC AND
ESPECIALLY ALONG AND NORTH OF INTERSTATE 40. IN ADDITION...HEAVY QPF
COULD CREATE SOME HYDRO ISSUES MONDAY NIGHT INTO TUESDAY MORNING
WITH THE FRONTOGENESIS MAX WEST OF THE PASSING 850 MB LOW LIKELY
LINGERING OVER THE EASTERN SLOPES OF THE MOUNTAIN. THE HEAVY
RAINFALL ON TOP OF ACCUMULATED SNOW AND ICE COULD CREATE SOME LOCAL
ICE DAMMING PROBLEMS ON SHALLOW SLOPED ROOFS. FINALLY...SURFACE
BASED CAPE VALUES OF 200 TO 300 J/KG ARE POSSIBLE TOWARD DAYBREAK
TUESDAY IN THE LOWER PIEDMONT...WITH 850 TO 500 MB LAPSE RATES OF
6.5 TO 7.0 DEG C/KM...ALONG WITH BACKED 50 KT 850 MB FLOW. THIS
COULD CREATE A BRIEF SEVERE THUNDERSTORM THREAT FROM CHESTER TO
MONROE OR THEREABOUTS AROUND DAYBREAK TUESDAY. OTHERWISE...DRYING
WILL DEVELOP FROM THE SOUTHWEST THROUGH TUESDAY AFTERNOON...WITH
NORTHERN MOUNTAIN UPSLOPE MOISTURE BRIEFLY DRYING UP.
A REINFORCING CLIPPER MAY DIVE INTO THE MEAN EASTERN TROUGH TUESDAY
NIGHT...WITH THE GFS MORE AMPLIFIED THAN THE ECMWF...PRODUCING
MAINLY ADDITIONAL UPSLOPE SNOW SHOWER COVERAGE OVER THE WESTERN
MOUNTAINS. HEIGHTS WILL BUILD EASTWARD FROM THE BROAD WESTERN RIDGE
WEDNESDAY THROUGH THURSDAY...WITH ASSOCIATED WARMING AND DRYING.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
AT KCLT AND ELSEWHERE...THE 6Z GFS AND LATEST HRRR HAVE TRENDED MUCH
WETTER WITH THIS FAST-MOVING WEAK LOW PRESSURE SYSTEM TODAY. THEY
ARE SUGGESTING THAT THERE MAY BE ENUF MOISTURE AND LLVL SUPPORT FOR
A BAND OF SNOW SHOWERS SOMEWHERE ACROSS THE PIEDMONT. THE HRRR HAS
IT SETTING UP FROM KAND TO SOUTH OF KUZA AND KCLT. STILL HAVE THE
TEMPO FOR KCLT FOR 14-18Z...BUT WENT A LITTLE MORE PESSIMISTIC WITH
RESTRICTIONS DUE TO INCREASED CHANCE FOR A HEAVIER SNOW SHOWER.
STILL THINK ODDS ARE FOR MAINLY VIRGA AND FLURRIES FOR MOST OF THE
AREAS EAST OF THE MOUNTAINS. AT KAVL...STILL EXPECT VCSH FOR SNOW
SHOWERS. CIGS SHOULD BE MAINLY VFR...BUT THE PESSIMISTIC GFS HAS
SOME MVFR CIGS/VSBY DUE TO SNOW. THIS EVENING THRU THE
OVERNIGHT...NW FLOW BEHIND THE DEPARTING LOW WILL RAMP UP...SCOURING
OUT THE LOW CLOUDS AND MOISTURE EAST OF THE MTNS...BUT KEEPING A
CHANCE FOR MVFR OR LOW VFR STRATUS AND PERIODIC SNOW SHOWERS AT KAVL
WITH GUSTY NNW WINDS. WINDS EAST OF THE MTNS WILL FAVOR NE THRU
ABOUT MIDDAY OR EARLY AFTN...THEN SWITCH TO SW FOR THIS AFTN AND
EVENING. THEN SHIFT TO NW LATE EVENING.
OUTLOOK...AN ARCTIC AIR MASS WILL BUILD OVER THE REGION THIS
WEEKEND...WITH UPSLOPE CLOUDS ON THE WEST SIDE OF THE APPALACHIANS.
A SIGNIFICANT WINTER WEATHER SYSTEM IS POSSIBLE EARLY NEXT WEEK.
CONFIDENCE TABLE...
14-20Z 20-02Z 02-08Z 08-12Z
KCLT HIGH 91% HIGH 90% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 95% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 91% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 98% HIGH 100% HIGH 100% HIGH 100%
KAND MED 78% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULE TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLET HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK:
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...WINTER WEATHER ADVISORY UNTIL 6 AM EST SATURDAY FOR NCZ033-
048>052.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM EST SUNDAY
FOR NCZ033-049-050.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST SATURDAY
FOR NCZ048-051-052-058-059.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...ARK/JAT
SHORT TERM...HG
LONG TERM...HG
AVIATION...ARK
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
653 AM EST FRI FEB 12 2016
.SYNOPSIS...
A FAST MOVING UPPER LEVEL DISTURBANCE WILL BRING A BRIEF CHANCE OF
PRECIPITATION TO MUCH OF THE AREA TODAY. A STRONG DOME OF CANADIAN
HIGH PRESSURE WILL SETTLE IN OVER THE WEEKEND...USHERING IN ANOTHER
PERIOD OF COLD TEMPERATURES. THIS WILL BE FOLLOWED BY ANOTHER
WEATHER SYSTEM WHICH WILL PRODUCE A BETTER CHANCE OF PRECIPITATION
EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 650 AM...THE MODELS SEEM TO BE LATCHING ONTO MORE MOISTURE OR
BETTER LLVL LIFT EAST OF THE MTNS. THE 6Z GFS AND THE LATEST RAP AND
HRRR NOW HAVE HIGHER POP/MORE COVERAGE OF SNOW SHOWERS ACROSS THE
PIEDMONT. IT LOOKS LIKE A BAND MAY SET UP SOMEWHERE ACROSS THE
UPSTATE. HOWEVER...CONFIDENCE IS STILL LOW. POPS MAY NEED TO BE
ADJUSTED UPWARD IF TRENDS ON RADAR LOOK TO BE LINING UP WITH THE
HRRR. OTHERWISE...FCST LOOKS ON TRACK.
AS OF 315 AM...A VIGOROUS SHORT WAVE CAN BE SEEN ON WATER VAPOR
IMAGERY DIVING INTO THE OHIO VALLEY TOWARD THE BASE OF A LONG WAVE
TROF ALONG THE EAST COAST. THIS WAVE WILL CROSS THE CWFA JUST AFTER
DAYBREAK...AND WILL BE ACCOMPANIED BY A 130 KT 300 MB JET. THIS WILL
RESULT IN STRONG MID AND UPPER LEVEL FORCING FROM ABOUT 12Z TO 18Z
TODAY. AT THE SFC...A WEAK ALBERTA CLIPPER WAS ANALYZED OVER
MO...AND WILL STREAK JUST SOUTH OF THE CWFA DURING THE DAY. LLVL FLOW
IS BACKING OUT OF THE WSW...BUT STRUGGLING TO TAP INTO MUCH MOISTURE.
SO THE FORECAST CHALLENGE FOR TODAY WILL BE HOW MUCH QPF WILL
ACCOMPANY THE SYSTEM...AS THE OP MODELS SHOW SOME SPREAD ON COVERAGE
AND AMOUNTS. THE 00Z NAM KEEPS THE PIEDMONT DRY...WHILE THE
OTHER OP MODELS HAVE SOME LIGHT AMOUNTS. I LIKE THE AGREEMENT OF THE
CAMS ON THE SIMULATED REFLECTIVITY...SHOWING LIGHT PRECIP BREAKING
OUT ACRS THE MTNS RIGHT AROUND DAYBREAK...THEN QUICKLY SPREADING
EAST ACROSS THE PIEDMONT DURING THE LATE MORNING HOURS. BY EARLY
AFTN...THE MODELS SHOW PRECIP CONFINED TO WESTERLY UPSLOPE AREAS
ALONG THE TN BORDER. I THINK MUCH OF WHAT THE CAMS ARE SHOWING WOULD
BE VIRGA...GIVEN THE MOISTURE MAINLY IN THE MID LEVELS. SO POPS SHOW
LIKELY IN THE MTNS...ESP NEAR THE TN BORDER...WHILE ONLY SLIGHT
CHANCE TO LOW-END CHANCE EAST. FCST PROFILES SHOW THAT THIS WOULD BE
A RAIN/SNOW EVENT...WITH WET-BULB EFFECTS ALLOWING FOR LIGHT SNOW
SHOWERS AND/OR FLURRIES JUST ABOUT ANYWHERE THIS MORNING. ACCUMS
THRU THE DAY WILL BE IN THE MTNS...WITH NOTHING MORE THAN A DUSTING
EXPECTED ELSEWHERE. TEMPS SHOULD BE ABOUT 10-15 DEGREES BELOW NORMAL
UNDER MOSTLY CLOUDY SKIES AND SPOTTY PRECIP.
TONIGHT...THE CLIPPER SYSTEM WILL ALREADY BE DEVELOPING A NEW LOW
OUT OVER THE ATLANTIC JUST EAST OF THE OUTER BANKS BY EARLY
EVENING...WHILE A STRONG ARCTIC HIGH (PRESSURE AROUND 1044 MB)
BUILDS IN ACROSS THE PLAINS TO THE SOUTHEAST STATES. THE SFC
PRESSURE GRADIENT NEVER GETS THAT IMPRESSIVE ATOP THE CWFA.
HOWEVER...THE 850 MB FLOW RAMPS UP OUT OF THE NW TO 40-55 KT ACROSS
THE NC MTNS WITH VERY STRONG CAA. THIS WILL RESULT IN A DOWN RIGHT
COLD AND BLUSTERY NIGHT IN THE MTNS...WITH THE ADDITION OF LINGERING
MOISTURE FOR NW FLOW SNOW SHOWERS. IN FACT...THE COLD AIR AND NEAR
PERFECT ORTHOGOTHAL DIRECTION COULD MAKE FOR EFFICIENT SNOW
PRODUCING SHOWERS ALONG THE TN LINE. THE EXPECTED SNOW WITH THE
CLIPPER ALONG WITH THE NW FLOW SNOW SHOULD RESULT IN TOTAL ACCUMS OF
2-4" ACROSS THE USUAL NW FLOW UPSLOPE AREAS. THIS ALONG WITH WINDS
IN THE 25-40 MPH RANGE AND GUSTS IN THE 40-55 MPH RANGE SEEMS TO
WARRANT A WINTER WEATHER ADVISORY. I WILL START IT AT NOON TO
EMCOMPASS THE SNOW ACCUMS EXPECTED TODAY...AND GO THRU 6 AM SATURDAY
(WHEN SNOW SHOWER ACTIVITY WILL TAPER OFF). IN ADDITION...TEMPS WILL
BE PLUMMETING INTO THE TEENS TO SINGLE DIGITS...SO WIND CHILLS WILL
BE IN THE -5 TO -15 F RANGE FOR MOST LOCATIONS ABOVE 3500 FT. A WIND
CHILL ADVISORY WILL BE ISSUED STARTING AT MIDNIGHT...ALTHOUGH SOME
LOCATIONS ABOVE 5000 FT OR SO MAY START SEEING DANGEROUS WIND CHILLS
EARLIER IN THE EVENING. THE REST OF THE CWFA SHOULD SEE CLEARING
SKIES AND LINGERING WINDS WITH CHILLY TEMPS ABOUT 8-15 DEGREES BELOW
NORMAL.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
AS OF 300 AM EST FRIDAY...A BROAD TROUGH OF LOW PRESSURE WILL EXTEND
SOUTHWARD ACROSS THE EASTERN UNITED STATES SATURDAY FROM A LOW
CENTER OVER SOUTHERN QUEBEC. ISOLATED TO SCATTERED NW FLOW SNOW
SHOWERS COULD LINGER ACROSS THE NORTHERN MOUNTAINS EARLY
SATURDAY...BUT WITH MOISTURE DIMINISHING THROUGH THE DAY. COLD
MORNING TEMPERATURES AND BRISK NW FLOW WILL PERMIT BITTER WIND
CHILLS TO CONTINUE THROUGH SATURDAY MORNING ACROSS THE
MOUNTAINS...AND ON INTO SATURDAY NIGHT/SUNDAY MORNING ACROSS THE
NORTHERN MOUNTAINS. MEANWHILE...VERY COLD AIR WILL DIVE SOUTHEAST
FROM CANADA INTO THE REGION ON THE BACK SIDE OF THE TROUGH AS THE
ASSOCIATED ARCTIC HIGH PRESSURE MOVES ACROSS THE MIDWEST ON SATURDAY
AND REACHES THE EASTERN SEABOARD BY LATE SUNDAY. IN THE COLD
AIRMASS...MAX TEMPERATURES WILL RUN AT LEAST 20 DEGREES BELOW CLIMO
IN MOST AREAS...WHILE SUNDAY MORNING MINS WILL BE 10 TO 20 DEGREES
BELOW CLIMO. A WIND CHILL ADVISORY WILL CONTINUE UNTIL MID SUNDAY
MORNING ACROSS THE NORTHERN NC MOUNTAINS.
THE UPPER FLOW WILL FLATTEN SLIGHTLY OVER THE EAST ON SUNDAY AS A
NORTHERN STREAM SHORTWAVE DIGS INTO THE MIDWEST WHILE A SOUTHERN
STREAM SYSTEM TAKES SHAPE FROM THE FOUR CORNERS REGION TOWARD TX.
THE FIRST HINT OF MID LEVEL UPGLIDE MOISTURE WILL ARRIVE IN THE CWA
FROM THE WEST ON SUNDAY...BUT WITH DRY LOW LEVELS PRECLUDING ANY
PRECIPITATION FROM REACHING THE GROUND THROUGH LATE DAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 300 AM EST FRIDAY...A WINTRY MIXED MAG OF PRECIPITATION IS
LOOKING LIKELY STARTING SUNDAY NIGHT INTO MONDAY GIVEN THE VERY COLD
AND DRY AIRMASS THAT WILL BE PRESENT OVER THE AREA BEFORE ONSET.
THERE IS GOOD MODEL CONSENSUS ON THE ENERGY WITH THE SOUTHERN STREAM
SYSTEM SHARPENING UP RAPIDLY OVER THE LOWER MS RIVER VALLEY SUNDAY
NIGHT INTO MONDAY. MEANWHILE...THE SURFACE HIGH CENTER TO THE NORTH
WILL RETREAT OFFSHORE. LOW LEVEL UPGLIDE MOISTURE WILL FILL IN
RAPIDLY ACROSS OUR AREA EARLY MONDAY...WITH THE 850 MB ZERO ISOTHERM
ALONG THE SOUTHERN FRINGE OF THE AREA AROUND DAYBREAK MOVING RAPIDLY
TOWARD THE NORTHERN FRINGE OF THE FORECAST AREA BY MID AFTERNOON.
EVEN THOUGH COLD AIR DAMMING IS VERY LIKELY...THE COLD AIR MAY ONLY
STAY DEEPLY ENTRENCHED EAST OF THE NORTHERN BLUE RIDGE GIVEN THE
INCREASINGLY OFFSHORE PARENT HIGH LOCATION. STILL...PROFILES ARE
PLENTY COLD FOR PRECIPITATION TO START AS SNOW THROUGHOUT BEFORE
DAYBREAK MONDAY...WITH A BLOSSOMING WARM NOSE THEN INVADING THE
SOUTHERN TIER OF THE FORECAST AREA MONDAY MORNING AND MOVING
NORTHWARD ACROSS THE REGION THROUGH THE DAY.
THE BEST UPPER FORCING ACTUALLY ARRIVES MONDAY NIGHT AS UPPER JET
DIVERGENCE BRIEFLY SETS UP AND DEEP LAYER Q VECTOR FORCING CROSSES
THE REGION AHEAD OF THE INCREASINGLY NEGATIVE TILT UPPER TROUGH.
FORCING AND MOISTURE WILL BE STRONGLY FOCUSED ON THE REGION LATE
MONDAY NIGHT/EARLY TUESDAY WITH THE SURFACE LOW CENTER LIKELY
TRACKING THROUGH THE CENTRAL CAROLINAS...THE CAD GETTING FURTHER
PINCHED OFF TO THE NORTH...AND THE HEAVIEST PRECIPITATION DURING THE
WARMEST PART OF THE EPISODE.
SO...THERE ARE PLENTY OF POTENTIAL HAZARDS. SIGNIFICANT ICE AND SNOW
ACCUMULATIONS WILL BE POSSIBLE...MAINLY OVER WESTERN NC AND
ESPECIALLY ALONG AND NORTH OF INTERSTATE 40. IN ADDITION...HEAVY QPF
COULD CREATE SOME HYDRO ISSUES MONDAY NIGHT INTO TUESDAY MORNING
WITH THE FRONTOGENESIS MAX WEST OF THE PASSING 850 MB LOW LIKELY
LINGERING OVER THE EASTERN SLOPES OF THE MOUNTAIN. THE HEAVY
RAINFALL ON TOP OF ACCUMULATED SNOW AND ICE COULD CREATE SOME LOCAL
ICE DAMMING PROBLEMS ON SHALLOW SLOPED ROOFS. FINALLY...SURFACE
BASED CAPE VALUES OF 200 TO 300 J/KG ARE POSSIBLE TOWARD DAYBREAK
TUESDAY IN THE LOWER PIEDMONT...WITH 850 TO 500 MB LAPSE RATES OF
6.5 TO 7.0 DEG C/KM...ALONG WITH BACKED 50 KT 850 MB FLOW. THIS
COULD CREATE A BRIEF SEVERE THUNDERSTORM THREAT FROM CHESTER TO
MONROE OR THEREABOUTS AROUND DAYBREAK TUESDAY. OTHERWISE...DRYING
WILL DEVELOP FROM THE SOUTHWEST THROUGH TUESDAY AFTERNOON...WITH
NORTHERN MOUNTAIN UPSLOPE MOISTURE BRIEFLY DRYING UP.
A REINFORCING CLIPPER MAY DIVE INTO THE MEAN EASTERN TROUGH TUESDAY
NIGHT...WITH THE GFS MORE AMPLIFIED THAN THE ECMWF...PRODUCING
MAINLY ADDITIONAL UPSLOPE SNOW SHOWER COVERAGE OVER THE WESTERN
MOUNTAINS. HEIGHTS WILL BUILD EASTWARD FROM THE BROAD WESTERN RIDGE
WEDNESDAY THROUGH THURSDAY...WITH ASSOCIATED WARMING AND DRYING.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AT KCLT AND ELSEWHERE...THE 6Z GFS AND LATEST HRRR HAVE TRENDED MUCH
WETTER WITH THIS FAST-MOVING WEAK LOW PRESSURE SYSTEM TODAY. THEY
ARE SUGGESTING THAT THERE MAY BE ENUF MOISTURE AND LLVL SUPPORT FOR
A BAND OF SNOW SHOWERS SOMEWHERE ACROSS THE PIEDMONT. THE HRRR HAS
IT SETTING UP FROM KAND TO SOUTH OF KUZA AND KCLT. STILL HAVE THE
TEMPO FOR KCLT FOR 14-18Z...BUT WENT A LITTLE MORE PESSIMISTIC WITH
RESTRICTIONS DUE TO INCREASED CHANCE FOR A HEAVIER SNOW SHOWER.
STILL THINK ODDS ARE FOR MAINLY VIRGA AND FLURRIES FOR MOST OF THE
AREAS EAST OF THE MOUNTAINS. AT KAVL...STILL EXPECT VCSH FOR SNOW
SHOWERS. CIGS SHOULD BE MAINLY VFR...BUT THE PESSIMISTIC GFS HAS
SOME MVFR CIGS/VSBY DUE TO SNOW. THIS EVENING THRU THE
OVERNIGHT...NW FLOW BEHIND THE DEPARTING LOW WILL RAMP UP...SCOURING
OUT THE LOW CLOUDS AND MOISTURE EAST OF THE MTNS...BUT KEEPING A
CHANCE FOR MVFR OR LOW VFR STRATUS AND PERIODIC SNOW SHOWERS AT KAVL
WITH GUSTY NNW WINDS. WINDS EAST OF THE MTNS WILL FAVOR NE THRU
ABOUT MIDDAY OR EARLY AFTN...THEN SWITCH TO SW FOR THIS AFTN AND
EVENING. THEN SHIFT TO NW LATE EVENING.
OUTLOOK...AN ARCTIC AIR MASS WILL BUILD OVER THE REGION THIS
WEEKEND...WITH UPSLOPE CLOUDS ON THE WEST SIDE OF THE APPALACHIANS.
A SIGNIFICANT WINTER WEATHER SYSTEM IS POSSIBLE EARLY NEXT WEEK.
CONFIDENCE TABLE...
12-18Z 18-24Z 00-06Z 06-12Z
KCLT HIGH 95% MED 79% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 94% HIGH 100%
KHKY HIGH 91% HIGH 83% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 86% HIGH 87% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULE TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLET HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK:
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...WINTER WEATHER ADVISORY FROM NOON TODAY TO 6 AM EST SATURDAY
FOR NCZ033-048>052.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM EST SUNDAY
FOR NCZ033-049-050.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST SATURDAY
FOR NCZ048-051-052-058-059.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...ARK
SHORT TERM...HG
LONG TERM...HG
AVIATION...ARK
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1006 AM EST FRI FEB 12 2016
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL PASS JUST SOUTH OF THE REGION THIS
AFTERNOON BRINGING PERIODS OF LIGHT SNOW OR SNOW SHOWERS
ESPECIALLY ACROSS THE MOUNTAINS. A SURGE OF ARCTIC AIR FOLLOWS
THIS SYSTEM OVERNIGHT RESULTING IN VERY WINDY CONDITIONS AND
BITTERLY COLD TEMPERATURES...ALONG WITH SOME ADDED SNOW SHOWERS
FOR THE FAR WESTERN SLOPES OF THE APPALACHIANS INTO SATURDAY. BY
MONDAY ANOTHER WINTER STORM SYSTEM WILL BEGIN TO AFFECT THE REGION
WITH THE POTENTIAL FOR SNOW AND MIXED PRECIPITATION THROUGH THE
FIRST PART OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM EST FRIDAY...
COLUMN CONTINUING TO SLOWLY MOISTEN AS AXIS OF ISENTROPIC LIFT
SPILLS EAST AHEAD OF THE STRONG UPPER SHORTWAVE SEEN ON WATER
VAPOR PASSING TO THE SOUTH. LATEST SHORT TERM GUIDANCE CONTINUES
TO VARY ON JUST HOW FAR EAST ANY OF THESE BANDS WILL MAKE IT WITH
SOME PRIMARILY CONFINED TO THE WESTERN SLOPES...WHILE OTHERS
INCLUDING THE WRF-ARW AND TO SOME DEGREE THE HRRR SPILL LIGHT
SNOW EAST TO THE BLUE RIDGE. ALTHOUGH THIS LOOKS
OVERDONE...PERIOD OF BACKING ALOFT MAY BE ENOUGH TO HELP PUSH
LIGHT SNOW FARTHER EAST THAN TYPICAL DOWNSLOPING WOULD ALLOW
ESPCLY WITH THE UPSTREAM TRAILING CHANNELED VORT AXIS SEEN BACK
IN KY. THUS BUMPED UP AMOUNTS A BIT ACROSS THE FAR SW PER CURRENT
TRAJECTORY OF SNOW TO THE WEST AND HEADING OUT TO THE BLUE RIDGE
FOR AT LEAST A COATING. APPEARS LEAST AMOUNT OF SNOW MAY OCCUR
OVER THE NORTH AS THE TRANSFER OF ENERGY FROM THE MOUNTAINS TO THE
COASTAL DUCKS FARTHER SOUTH THROUGH THE AFTERNOON. STILL GOING
HEADLINES ON TRACK FOR AN INCH OR SO TODAY OUT WEST AND COMBINED
UPSLOPE OVERNIGHT SO NO CHANGES THERE OTHER THAN TO TWEAK AMOUNTS.
ALSO MADE SOME SLIGHT UPWARD ADJUSTS TO TEMPS MAINLY EAST WHERE
COULD SURGE UP AS A FEW BREAKS DEVELOP AHEAD OF ANY PRECIP THAT
ATTEMPTS TO HEAD EAST OF THE RIDGES. THINK MOST PTYPE EVEN OUT
THERE TO BE SNOW GIVEN COLDNESS ALOFT SO RUNNING WITH MOSTLY
SNOW/SNOW SHOWERS.
WILL NEED TO TAKE A LOOK AT THE WINDS OVERNIGHT INTO SATURDAY
MORNING BEHIND THE PASSING ARCTIC FRONT AS COULD SEE WARNING
CRITERIA SW BUT WILL AWAIT 12Z GUIDANCE BEFORE UPDATING.
PREVIOUS DISCUSSION AS OF 400 AM EST FRIDAY...
THE MAIN WEATHER PLAYERS FOR OUR REGION TODAY AND TONIGHT WILL BE AN
UPPER LEVEL SHORT WAVE BRINGING SOME LIGHT SNOW TO THE FAR WESTERN
PORTION OF THE AREA BEFORE A STRONG COLD FRONT MOVES THROUGH AND SETS
OFF ANOTHER ROUND OF UPSLOPE SNOW SHOWERS WEST OF THE BLUE RIDGE.
BELIEVE THE MOUNTAIN EMPIRE REGION WILL SEE AN INCH OR LESS OF SNOW
BEFORE THE UPSLOPE REALLY KICKS IN AND PROVIDES ADDITIONAL ACCUMULATIONS
ALONG THE FAR WESTERN SLOPES THROUGH TONIGHT. THE AIR MOVING IN BEHIND
THE FRONT IS QUITE COLD INDEED AND WILL CREATE SOME VERY STEEP LOW LEVEL
LAPSE RATES AND EVEN A BIT OF CAPE...WHICH MAY BRING US ANOTHER CHANCE
FOR A PERIOD OF THUNDERSNOW EARLY TONIGHT. MESO MODELS ALSO INDICATE
A DECENT UPSTREAM CONTRIBUTION TO THE MOISTURE FROM THE GREAT LAKES.
BELIEVE THESE FACTORS WILL COMBINE TO GENERATE SNOW ACCUMULATIONS
GENERALLY IN THE 2 TO 4 INCH RANGE FOR THE WESTERN SLOPES WITH SOME
LOCALLY HIGHER AMOUNTS POSSIBLE SO WILL ISSUE AN ADVISORY FOR THIS AREA
FROM THIS AFTERNOON THROUGH TONIGHT.
LOW LEVEL WINDS WILL ALSO START TO INCREASE TONIGHT AND GOOD MOMENTUM
TRANSFER IN THE BOUNDARY LAYER WILL ALLOW FOR QUITE A BIT OF WIND
OVERNIGHT WITH GUSTS OVER 40 MPH EXPECTED ESPECIALLY OVER THE HIGHER
TERRAIN. THIS WILL COMBINE WITH TEMPERATURES WEST OF THE BLUE RIDGE
FALLING INTO THE SINGLE DIGITS TO GENERATE WIND CHILL VALUES OF 5 TO 15
BELOW ZERO...WITH READINGS TO 25 BELOW FOR WESTERN GREENBRIER COUNTY IN
WEST VIRGINIA. WINDS WILL GRADUALLY SUBSIDE ON SATURDAY BUT THE
COMBINATION OF WIND AND VERY COLD TEMPERATURES WILL CONTINUE TO
GENERATE VERY LOW WIND CHILL VALUES THROUGH SUNDAY MORNING. A WIND
CHILL ADVISORY WILL BE ISSUED FOR THE AREA ALONG AND WEST OF THE BLUE
RIDGE FROM TONIGHT THROUGH SUNDAY MORNING WITH A WIND CHILL WARNING FOR
WESTERN GREENBRIER. CONDITIONS EAST OF THE RIDGE WILL NOT BE QUITE AS
SEVERE AS LOWS TONIGHT REACH THE 15 TO 20 DEGREE RANGE WITH WIND CHILL
VALUES INTO THE SINGLE DIGITS.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
AS OF 430 AM EST FRIDAY...
COLDEST AIR OF THE SEASON STILL SLATED TO BE SPREADING INTO THE
REGION FOR SATURDAY...WITH TEMPERATURES BOTTOMING OUT SUNDAY
MORNING. THE MODELS HAVE BACKED OFF THE INTENSITY OF THE COLD AIR
MASS JUST SLIGHTLY WITH EACH SUCCEEDING RUN...NOW STOPPING AROUND
-22C ACROSS THE FAR NORTHERN PORTION OF THE CWA. SIMILAR EVENTS
THE PAST TWO YEARS HAVE SEEN READINGS CLOSER TO -25/-26C...SO FEEL
CONFIDENT THAT MORNING LOW TEMPERATURES SUNDAY MORNING WILL FALL A
COUPLE OF DEGREES SHY OF WHAT WE SAW THE LAST COUPLE OF YEARS WITH
SIMILAR ARCTIC OUTBREAKS. ALSO...SNOW COVER IS LIMITED EAST OF
THE ALLEGHANY FRONT AND THE MOUNTAINS OF SW VA/NW NC...SO THAT
WILL ALSO NOT HELP DRIVE TEMPERATURES TO THE LEVELS WE SAW AROUND
THIS TIME LAST YEAR. NONETHELESS...IT WILL BE BITTERLY COLD AND
VERY WINDY...PROMPTING A CONTINUATION OF THE WIND CHILL ADVISORIES
WEST OF THE BLUE RIDGE AND THE WARNING FOR WESTERN GREENBRIER.
WINDS WILL BEGIN TO DIMINISH LATE IN THE DAY AND SATURDAY
NIGHT...BUT WITH TEMPERATURES FALLING INTO THE SINGLE DIGITS AND
NEAR 0 TO -5F AT THE HIGHER ELEVATIONS...THE ADVISORIES/WARNINGS
ARE WARRANTED TO CONTINUE INTO SUNDAY MORNING AS IT WILL TAKE VERY
LITTLE FOR WIND CHILLS TO MEET CRITERIA WITH TEMPS THAT LOW.
UPSLOPE SNOW SHOWERS SHOULD BE WINDING DOWN SATURDAY MORNING
FAIRLY QUICKLY AS THE VERY DRY ARCTIC AIR MASS SPREADS INTO THE
REGION. WILL KEEP SLIGHT CHANCE TO LOW CHANCE POPS FOR SNOW
SHOWERS GOING THROUGH MID-DAY...THEN END THEM...ALBEIT SOME
FLURRIES COULD CONTINUE INTO THE AFTERNOON AS ARCTIC COLD-
ADVECTION SQUEAKS OUT ANY REMAINING MOISTURE. WINDS WILL BE
STRONG AND GUSTY THROUGHOUT THE DAY...BUT LIKELY DROP BELOW
ADVISORY CRITERIA IN THE WEST DURING THE AFTERNOON...ALTHOUGH THAT
IS LUMPED INTO THE WSW.
THE ARCTIC HIGH SETTLES OVER THE REGION SUNDAY MORNING WITH...AS
NOTED ABOVE...BITTERLY COLD TEMPERATURES...BUT WINDS TRENDING
TOWARD CALM. BY AFTERNOON...THE ARCTIC HIGH HAS ALREADY SHIFTED
TOWARD THE VA/MD COAST WITH RETURN FLOW EVIDENT ESPECIALLY IN
SOUTHWEST VA. A NORTHERN STREAM SHORT WAVE QUICKLY MOVES TOWARD
THE REGION BY SUNDAY AFTERNOON...WITH INCREASING MOISTURE FROM TOP
DOWN. THE ANTECEDENT AIR MASS WILL CLEARLY BE VERY DRY AND COLD
AND NOT SURE HOW QUICKLY THE AIR MASS WILL SATURATE TO ALLOW
GENERATED PRECIPITATION ALOFT TO REACH THE GROUND. INDICATIONS ARE
THAT THIS SHOULD BEGIN TO TAKE PLACE AFTER SUNSET IN THE WEST AND
CLOSER TO MIDNIGHT IN THE EAST. THUS...WILL LEAVE THE DAYTIME
HOURS OF SUNDAY DRY WITH POPS BELOW 15 PERCENT. ALL PRECIPITATION
SUNDAY NIGHT WILL BE SNOW ACROSS THE ENTIRE CWA AS THE SOUNDINGS
REMAIN BELOW FREEZING AT ALL LEVELS.
AS WE MOVE INTO MONDAY...THE SITUATION BECOMES INCREASINGLY
COMPLICATED. THE NORTHERN STREAM SHORT WAVE WILL MOVE NORTHEAST OF
THE REGION EARLY MONDAY...WHILE A STRONGER SOUTHERN STREAM SHORT
WAVE DEEPENS INTO THE MID-SOUTH. DEEP SURFACE LOW PRESSURE WILL
THEN DEVELOP IN RESPONSE TO THIS SECOND SOUTHERN STREAM SHORT WAVE
ACROSS THE MID-SOUTH...MOVING TOWARD THE EASTERN TN VALLEY BY
MONDAY EVENING. ALL OF THE MODELS HAVE TAKEN A SLIGHT WEST JOG
WITH THE SURFACE LOW PRESSURE...RESULTING IN THE POTENTIAL FOR
WARMER AIR FROM THE SOUTH AND SOUTHEAST TO ENCROACH ON THE REGION.
NONETHELESS...THE ANTECEDENT AIR MASS WILL BE VERY COLD AND MODELS
OFTEN ADVERTISE A WARMUP TOO QUICKLY WITH THIS TYPE OF SITUATION.
A WARM FRONT WILL LIE ACROSS THE REGION MONDAY NIGHT...THEN BEGIN
TO LIFT NORTHWARD EARLY TUE. THIS IS WHEN THE P-TYPE ISSUES WILL
BEGIN WITH A TRANSITION FROM SNOW TO SLEET TO FREEZING RAIN AND
PERHAPS EVEN RAIN IN PARTS OF THE PIEDMONT. THIS ENTIRE PERIOD
WILL EVENTUALLY HAVE TO BE HANDLED BY TOP-DOWN OR SIMILAR P-TYPE
PROCEDURES...BUT GIVEN IT IS STILL OUT IN THE DAY 4 AND BEYOND
PERIOD....WILL STICK WITH A RAIN/SNOW MIXTURE FOR NOW. ALTHOUGH
SNOW/SLEET/ICE AMOUNTS STILL HIGHLY IN QUESTION...IT STILL APPEARS
QUITE CERTAIN THAT WINTER STORM CRITERIA WILL LIKELY BE MET ACROSS
MUCH OF THE CWA IN THE SUN NIGHT THROUGH EARLY TUE TIME
FRAME...WITH STILL THE POTENTIAL FOR SIGNIFICANT SNOWFALL
ACCUMULATIONS IN THE WESTERN MOUNTAINS. THUS...WILL CONTINUE TO
HIGHLIGHT THIS POTENTIAL IN THE HWO. A WINTER STORM WATCH FOR THIS
PERIOD WILL LIKELY NEED TO FOLLOW ON THE HEELS OF THE CURRENT
WINTER WEATHER ADVISORIES.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 100 PM EST THURSDAY...
A DEEPENING SURFACE LOW...REMAINING MOSTLY INLAND...WILL TRACK
ACROSS THE CWA TUE...MOVING TOWARD THE NORTHERN MID-ATLANTIC BY
EVENING. SIGNIFICANT WINTER WEATHER WILL LIKELY CONTINUE FOR MUCH
OF THE CWA...BUT POTENTIALLY TRANSITIONING TO RAIN ACROSS THE
PIEDMONT. BUFKIT SHOWS CONSIDERABLE VERTICAL MOTION IN THE SNOW
GROWTH ZONE EARLY TUESDAY...SO THERE COULD BE A BURST OF HEAVY
SNOW/SLEET BEFORE THE DRY SLOT SPREADS INTO THE REGION FROM THE
SOUTHWEST AND SHUTS OFF THE HEAVIER PRECIPITATION...WHICH SHOULD
OCCUR BY MIDDAY TUE. BY EVENING...COLDER AIR BEGINS TO FILTER
BACK INTO THE WESTERN AREAS AND UPSLOPE SNOW SHOWERS COMMENCE ONCE
AGAIN.
IN THE WAKE OF THE STRONG SYNOPTIC SYSTEM TUESDAY...ANOTHER
CLIPPER IS EVIDENT IN CONTINUED NORTHWEST FLOW ALOFT. OVERALL
WARMING OF ANY SIGNIFICANCE LOOKS LIMITED DURING THIS PERIOD.
ALTHOUGH PREVIOUS RUNS OF THE GFS SHOWED SUBSTANTIAL WARMING
DURING THIS TIME FRAME...THAT IS NOT EVIDENT TODAY. MEXMOS KEEPS
WESTERN AREAS MOSTLY AT OR BELOW FREEZING THROUGH MIDWEEK...WITH
ONLY LIMITED WARMING DURING THE LATER HALF OF THE WEEK. THE
CLIPPER TUE NIGHT/WED...COULD BRING ADDITIONAL MINOR SNOW
ACCUMULATIONS TO THE WESTERN PARTS OF THE CWA BEFORE MOVING
NORTHEAST OF THE REGION. OUTSIDE OF UPSLOPE SNOW SHOWERS...THAT
SHOULD BE THE LAST OF ANY SYNOPTIC-SCALE INDUCED PRECIPITATION FOR
THIS PERIOD.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
AS OF 630 AM EST FRIDAY...
DEVELOPING COASTAL LOW WILL BRING NELY WINDS AND MAYBE A FLURRY TO KDAN
EARLY IN THE PERIOD...BUT THIS LOW IS NOT EXPECTED TO HAVE A MAJOR
IMPACT ON TAF SITES. HOWEVER...THE APPROACHING SHORT WAVE AND COLD
FRONT ARE EXPECTED TO SPREAD SIGNIFICANT WEATHER TO ALL TAF SITES
STARTING MID/LATE MORNING. EAST OF THE BLUE RIDGE SOME SNOW SHOWERS AND
A TEMPO MVFR CIG MAY AFFECT KROA/KLYH/KDAN BUT FROPA WILL BRING NWLY
WINDS AND DOWNSLOPE TO BRING VFR CONDITIONS FOR THE LATTER PORTION OF
THE PERIOD. FOR KBCB/KBLF/KLWB THE NWLY WINDS WILL BE UPSLOPE AND THIS
WILL KEEP SNOW SHOWERS AT THESE LOCATIONS WITH MVFR/IFR CIGS/VSBYS.
BEHIND THE FRONT ALL SITES WILL SEE SIGNIFICANT WIND GUSTS AS A WELL
MIXED BOUNDARY LAYER ALLOWS FOR EFFICIENT MOMENTUM TRANSFER OF
INCREASING LOW LEVEL FLOW. EXPECT G40KT AT KROA WITH GUSTS AOA 30KT FOR
KBCB/KLWB/KBLF.
EXTENDED DISCUSSION...
EXPECT VFR SAT AFTERNOON THROUGH SUNDAY WITH SUBSIDING
WINDS...THOUGH SOME MVFR INTO SAT NIGHT POSSIBLE AT BLF.
THE NEXT LOW PRESSURE SYSTEM WILL ARRIVE ON SUNDAY NIGHT.
CONFIDENCE IS HIGH THAT POOR FLYING WEATHER WILL TAKE PLACE
DURING MONDAY AND TUESDAY. THIS SYSTEM WILL LIKELY BRING WINTRY
PRECIPITATION TO MUCH OF THE AREA...BUT FURTHER UPDATES FROM THE
LONGER RANGE MODELS MAY IMPACT THE DETAILS ON PRECIPITATION TYPE
AND STORM TRACK.
&&
.CLIMATE...
COLDEST AIR OF THE SEASON ARRIVES THIS WEEKEND. SEVERAL RECORD LOW
MAX TEMPERATURES AND LOW TEMPERATURES ARE POSSIBLE. BELOW ARE THE
CURRENT RECORDS FOR SATURDAY 2/13 AND SUNDAY 2/14.
SATURDAY 02/13/2016
SITE MINT YEAR LOMAX YEAR
KBLF 4 1988 19 1988
KDAN 11 1955 32 1981
KLYH 5 1979 9 1899
KROA 8 1917 18 1914
KRNK -4 1969 14 1955
SUNDAY 02/14/2016
SITE MINT YEAR LOMAX YEAR
KBLF 5 1971 16 1960
KDAN 15 1986 32 1986
KLYH 4 1899 24 1905
KROA 10 1943 26 1986
KRNK -2 1969 24 1986
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WIND CHILL ADVISORY FROM 11 PM THIS EVENING TO 10 AM EST
SUNDAY FOR VAZ007-009>020-022>024-032>035.
WINTER WEATHER ADVISORY UNTIL 7 AM EST SATURDAY FOR VAZ007-009-
015.
NC...WIND CHILL ADVISORY FROM 11 PM THIS EVENING TO 10 AM EST
SUNDAY FOR NCZ001-002-018.
WINTER WEATHER ADVISORY UNTIL 7 AM EST SATURDAY FOR NCZ001-018.
WV...WIND CHILL ADVISORY FROM 11 PM THIS EVENING TO 10 AM EST
SUNDAY FOR WVZ042>044-507.
WINTER WEATHER ADVISORY UNTIL 7 AM EST SATURDAY FOR WVZ042-043-
508.
WIND CHILL WARNING FROM 11 PM THIS EVENING TO 10 AM EST SUNDAY
FOR WVZ508.
&&
$$
SYNOPSIS...JH/MBS
NEAR TERM...JH/MBS
SHORT TERM...RAB
LONG TERM...AMS/RAB
AVIATION...MBS/WP
CLIMATE...CF
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
128 PM PST FRI FEB 12 2016
.SYNOPSIS...
FAIR AND VERY WARM WEATHER AGAIN TODAY...WITH TEMPERATURES LOWERING
A FEW DEGREES ON SATURDAY AS THE RIDGE OF HIGH PRESSURE WEAKENS.
ANOTHER WARM-UP EXPECTED SUNDAY THROUGH TUESDAY AS THE RIDGE ALOFT
RE-BUILDS AND STRONGER OFFSHORE FLOW MOVES IN. LOCALLY STRONG AND
GUSTY NORTHEAST TO EAST WINDS POSSIBLE IN THE PASSES...CANYONS AND
COASTAL FOOTHILLS SUNDAY THROUGH TUESDAY...WITH STRONGEST WINDS ON
MONDAY. BY NEXT WEDNESDAY...THE RIDGE WILL WEAKEN AND ONSHORE FLOW
RETURNS...RESULTING IN DECREASING TEMPERATURES. A LOW PRESSURE
TROUGH WILL CONTINUE TO COOLING TREND AND MAY BRING SOME SHOWERS TO
THE REGION ON THURSDAY.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
AFTERNOON VISIBLE SATELLITE SHOWS A LARGE AREA OF FOG OVER THE
OFFSHORE WATERS NEAR SAN CLEMENTE ISLAND...WITH THIN HIGH CLOUDS TO
THE NORTHWEST. LOOKING AT THE 12Z MIRAMAR SOUNDING AND COMPARING TO
YESTERDAYS 12Z SOUNDING...THE ATMOSPHERE HAS COOLED SLIGHTLY UP
THROUGH 600 MB. MEANWHILE...OFFSHORE PRESSURE GRADIENTS CONTINUE TO
WEAKEN...WITH GRADIENTS OF 7.0 MB FROM SAN DIEGO TO TONOPAH AND 7.9
MB FROM SAN DIEGO TO SALT LAKE CITY...WHEREAS THE GRADIENTS WERE
12.9 MB AND 14.4 MB RESPECTIVELY AT THIS TIME YESTERDAY. AS A
RESULT...NORTHEAST TO EAST WIND GUSTS ARE ONLY IN THE 15-20 MPH
RANGE IN THE PASSES/CANYONS AND COASTAL FOOTHILLS. THE WEAKER
OFFSHORE FLOW IS ALLOWING FOR A SEA BREEZE TO BRING MINOR COOLING TO
THE COAST TODAY...WITH SAN DIEGO ONLY SHOWING A TEMPERATURE OF 77
RIGHT NOW...WHEREAS IT WAS 82 AT 1 PM YESTERDAY. HOWEVER...HIGHS
ELSEWHERE WILL STILL BE 10-20 DEGREES...AND LOCALLY 25
DEGREES...ABOVE NORMAL. IN THE INLAND COASTAL AREAS...VALLEYS AND
LOWER DESERTS...EXPECT HIGHS IN THE MID-TO-UPPER 80S...MID-TO-UPPER
70S AT THE BEACHES AND HIGH DESERTS...70S AT THE LOWER MOUNTAIN
SLOPES...AND THE LOW 60S AT THE HIGH ELEVATIONS. WE MAY HAVE A FEW
STATIONS REACHING RECORD HIGHS AGAIN TODAY.
WATER VAPOR IMAGERY INDICATES AN UPPER LEVEL RIDGE OVER SOUTHERN
CALIFORNIA SLOWLY BEING NUDGED EAST...WITH A TROUGH FAR TO THE WEST.
WITH OFFSHORE FLOW CONTINUING TO WEAKEN TONIGHT...IT MAY ALLOW FOR
SOME DENSE FOG TO REACH THE COASTAL AREAS UP TO A FEW MILES INLAND
LATE TONIGHT INTO SATURDAY MORNING. IN FACT...THE 19Z HRRR SEEMS TO
HAVE INITIALIZED THE AREA OF FOG OFFSHORE PRETTY WELL...AND HAS
DENSE FOG MOVING INTO THE COAST BY MID-EVENING. A TROUGH MOVING
INLAND OVER THE PACIFIC NORTHWEST SATURDAY WILL CREATE SOME COOLING
FOR SATURDAY...BUT TEMPERATURES WILL STILL BE WELL ABOVE NORMAL.
SUNDAY INTO TUESDAY...RIDGING TO THE WEST WILL BUILD BACK OVER THE
REGION. THIS...IN ADDITION TO STRENGTHENING OFFSHORE FLOW RESULTING
FROM STRONG SURFACE HIGH PRESSURE OVER THE GREAT BASIN...WILL CREATE
ANOTHER WARM-UP...WITH HIGHS ONCE AGAIN REACHING 10-20 DEGREES...AND
LOCALLY 25 DEGREES...ABOVE NORMAL. MONDAY AND TUESDAY LOOK LIKE THE
WARMEST DAYS...WITH DAILY HIGH TEMPERATURE RECORDS AT A FEW TO
SEVERAL STATIONS POSSIBLY GETTING BROKEN. MODELS INDICATE THAT THE
OFFSHORE PRESSURE GRADIENTS FROM SAN DIEGO TO TONOPAH STRENGTHEN TO
ABOUT 7-10 MB SUNDAY...AND THEN 11-16 MB MONDAY. MEANWHILE...UPPER
SUPPORT INCREASES AS WELL...WITH 850 MB WINDS OUT OF THE NORTHEAST
REACHING ABOUT 10-20 KT ON SUNDAY...AND THEN 15-30 KT ON MONDAY.
THUS...LOOK FOR WEAK TO LOCALLY MODERATE SANTA ANA WINDS ON
SUNDAY...WITH NORTHEAST TO EAST WIND GUSTS OF 25-40 MPH IN THE
PASSES/CANYONS AND COASTAL FOOTHILLS...AND THEN WINDS STRENGTHENING
FURTHER MONDAY...WITH NORTHEAST TO EAST WIND GUSTS REACHING 40-50
MPH AND LOCALLY 60 MPH IN THE PASSES/CANYONS AND COASTAL FOOTHILLS.
OFFSHORE FLOW WEAKENS A LITTLE ON TUESDAY.
THE RIDGE STARTS TO WEAKEN AND WE TURN BACK ONSHORE DURING THE DAY
WEDNESDAY AS A TROUGH APPROACHES THE WEST COAST...CREATING COOLER
CONDITIONS. THE LONG-RANGE MODELS ARE STILL IN A FAIR AMOUNT OF
DISAGREEMENT REGARDING HOW DEEP AND STRONG THE TROUGH WILL BE AS IT
MOVES INLAND ON THURSDAY. THE 12Z GFS IS PRETTY SIMILAR TO THE 06Z
RUN...SHOWING A WEAK TROUGH AND ASSOCIATED PRECIPITATION MOVING BY
TO OUR NORTH...LEAVING US MOSTLY DRY. HOWEVER...THE 12Z ECMWF IS
MUCH STRONGER...WETTER AND SLOWER FOR SOUTHERN CALIFORNIA. THE 12Z
CANADIAN SEEMS TO SHOW COMPROMISE BETWEEN THE ECMWF AND GFS.
CONSIDERING THAT 2 OF THE 3 LONG RANGE MODELS CONSISTENTLY SHOW
PRECIP FOR THURSDAY...HAVE INCREASED THE POPS A BIT. AT THE VERY
LEAST...EXPECT THE COOLING TREND TO CONTINUE INTO THURSDAY.
&&
.AVIATION...
122100Z...FEW-SCT CLOUDS AOA 20000 FT MSL AND UNRESTRICTED VIS
THROUGH SATURDAY. THERE IS A CHANCE OF LOW CLOUDS AND FOG WITH VIS
2SM OR LESS JUST REACHING THE COAST LATE TONIGHT INTO SATURDAY
MORNING...POSSIBLY VCNTY KSAN/KCRQ/KSNA. CONFIDENCE IS SLIGHTLY
HIGHER AT THIS TIME FOR FOG OCCURRENCE DUE TO NEW HI-RES MODEL
GUIDANCE. WILL STICK WITH VCFG FOR COASTAL TAF SITES FOR NOW
THOUGH...BUT MAYBE A FEW MORE LOW CLOUDS.
&&
.MARINE...
100 PM...FOG WITH VISIBILITY 1SM OR LESS IS LIKELY OVER THE COASTAL
WATERS AND APPROACHING THE COAST TONIGHT THROUGH SATURDAY MORNING.
OTHERWISE NO HAZARDOUS MARINE WEATHER IS EXPECTED SATURDAY AFTERNOON
THROUGH TUESDAY.
&&
.BEACHES...
100 PM...A LONG-PERIOD SWELL FROM 290 DEGREES WILL BUILD
TODAY...PEAKING SATURDAY AT 9 FT/18 SEC. THIS WILL GENERATE HIGH
SURF OF 4 TO 8 FEET TODAY THROUGH SUNDAY WITH HIGHEST SETS NORTH OF
NEWPORT BEACH AND SOUTH OF DEL MAR. A HIGH SURF ADVISORY REMAINS IN
EFFECT FROM 10 AM TODAY THROUGH 8 PM SUNDAY. SWELL AND SURF WILL
SUBSIDE MONDAY.
&&
.FIRE WEATHER...
LIGHT OFFSHORE WINDS WILL CONTINUE THROUGH SATURDAY...THEN OFFSHORE
WINDS STRENGTHEN A LITTLE SUNDAY...WITH NORTHEAST TO EAST GUSTS 25-
40 MPH IN THE PASSES/CANYONS AND COASTAL FOOTHILLS...AND THEN
STRENGTHEN FURTHER ON MONDAY...WITH NORTHEAST TO EAST GUSTS 40-50
MPH AND LOCALLY 60 MPH IN THE PASSES/CANYONS AND COASTAL FOOTHILLS.
THE OFFSHORE FLOW WILL COMBINE WITH VERY WARM CONDITIONS AND MINIMUM
RELATIVE HUMIDITIES IN THE SINGLE DIGITS TO TEENS TO CREATE ELEVATED
TO POSSIBLY CRITICAL FIRE WEATHER CONCERNS ON MONDAY. OVERNIGHT
HUMIDITY RECOVERIES LOOK TO BE POOR TO LOCALLY MODERATE.
HUMIDITY WILL START TO INCREASE WEDNESDAY AS ONSHORE FLOW RETURNS
AND A TROUGH APPROACHES FROM THE PACIFIC. THIS TROUGH COULD PRODUCE
WETTING RAINS NEXT THURSDAY.
&&
.SKYWARN...
SKYWARN ACTIVATION WILL NOT BE NEEDED TODAY.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...HIGH SURF ADVISORY UNTIL 8 PM PST SUNDAY FOR ORANGE COUNTY
COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS.
PZ...NONE.
&&
$$
PUBLIC/FIRE WEATHER...HARRISON
AVIATION/MARINE/BEACHES...TS
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
400 PM EST FRI FEB 12 2016
.SYNOPSIS...
AN ARCTIC FRONT WILL CROSS THE AREA TONIGHT. HIGH PRESSURE WILL
BUILD ACROSS THE AREA LATER THIS WEEKEND AND THEN MOVE EAST
SUNDAY NIGHT. LOW PRESSURE WILL DEEPEN ACROSS THE LOWER MISSISSIPPI
VALLEY MONDAY AND THEN MOVE ALONG THE APPALACHIANS TUESDAY AND THEN
NORTH INTO CANADA WEDNESDAY. MORE HIGH PRESSURE WILL BUILD IN FOR
THE END OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
FLURRIES POSSIBLE POCONOS AND EXTREME SOUTH EDGE OF OUR AREA LATE
THIS DAY AS PER RADAR AND OBS.
TONIGHT...SHALLOW MOIST ADVECTION ON S-SW FLOW PRIOR TO THE CFP.
SNOW SHOWERS OR FLURRIES APPEAR PROBABLE FOR A FEW HOURS NEAR
MIDNIGHT AS PER A BLEND OF MODELS AND WPC. HRRR AND HRRX LOOK
ACCEPTABLE AS A TIMING GUIDE. SW WIND MAY GUST 15 MPH EARLY
TONIGHT. THEN A WIND SHIFT TO NORTHWEST AND GUSTY 20-30 MPH BY
DAWN SATURDAY....POSSIBLE ISOLATED GUSTS 40-45 MPH AT SUNRISE PER
ARRIVING STRONG CAA AND PRES RISES.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
WIND CHILL ADVY AND WIND ADVY POSTED IN ADDITION TO PRIOR WIND
CHILL WARNING. SPS FROM YDY NO LONGER NEEDED.
DEEPENING BOUNDARY LAYER MOMENTUM TRANSFER IS FEATURED ASSOCIATED
WITH THE ONCOMING ARCTIC AIRMASS INVASION. LARGE LOW LVL LAPSE
RATES AND BTV SNOW SQUALL PARAMETER INDICATING A POSSIBILITY OF
FLURRIES OR SQUALLS BUT WILL THE SFC TT/TD SPREAD EXCEED 25F AND
MAKE THOSE SQUALLS JUST VIRGA? SEEMS LIKE BEST CHC FOR A SQUALL
WOULD BE THE MORNING AND IN THE REGION S OF THE PA TURNPIKE.
AM THINKING OF GUSTS 50 MPH IN THE POCONOS AND ALSO SCATTERED 50
MPH GUSTS DEVELOPING IN THE KRDG-KPHL-KILG KACY AND NORTH SIDE OF
DE BAY SLOT FOR THE AFTN. WIND ADVY ISSUED. NOT SURE HOW MANY
NOTICED BUT THE NAM AND OP ECMWF HAVE BEEN A LITTLE CONSERVATIVE
ON WIND. JUST LOOKS LIKE TOO DEEP A MIXED LAYER TO AVOID CONNECTING
A FEW EDDIES OF 50 KT GUSTS DOWN FROM 6000 TO 7000 FT ALOFT. THE
INVERSION SINKS TO NEAR 850 MB LATE IN THE DAY SATURDAY.
STRONGEST WINDS ASIDE FROM THE INITIAL BURST NEAR 11-12Z, MAY BE
LATE AFTN AND EVENING. FOR NOW WANTED TO LIMIT ADVY ONLY TO THE
DAY AND IF ITS GUSTING 40 KT AT 3 PM SATURDAY, THEN SUSPECT IT CAN
GUST 40-45 KT THROUGH 10 PM. CONFIDENCE ON VERIFICATION IS
AVERAGE. THIS COULD BE OVERDONE BUT HAVE SEEN REPEATEDLY THE POCS
WIND MATCH THE OVERWATER WIND NEAR 44065, AND NW FLOW STRONGEST
GUSTS NEAR A RDG-PHL LINE. ALSO ADDED MD E SHORE ALONG THE STILL
WARM CHES BAY AND DELAWARE ALONG THE BAY FROM WILMINGTON TO LEWES
WHERE I THINK SOME HEFTY GUSTS COULD ADD TO THE CHILL.
OTHERWISE WIDESPREAD GUSTS 40 MPH SATURDAY WITH PARTLY TO MOSTLY
SUNNY SKIES .. TENDING TO CLEAR LATE DAY.
WINDS WERE DERIVED FROM THE GFS, THE TEMPS FROM THE NAM MOS BLENDED
WITH THE 2M TEMPS OF THE 12Z GFS/NAM. HRRX INDICATED NEAR 0 AT KMPO
AT 17Z SATURDAY...WITHOUT A WIND CHILL. CANT SEE IT MORE THAN 17F
AT PHL AT 18Z SAT...MAYBE EVEN A DEGREE OR 2 COLDER?.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
THE HEART OF THE ARCTIC AIR MASS WILL BE ACROSS THE AREA SATURDAY
NIGHT AND INTO SUNDAY. DANGEROUSLY COLD TEMPERATURES AND WIND CHILL
READINGS WILL BE ACROSS THE ENTIRE FORECAST AREA. NO PRECIPITATION
IS EXPECTED. WINDS WILL DIMINISH THROUGH THE DAY SUNDAY. LOW
TEMPERATURES SAT NIGHT AROUND -10 ACROSS THE FAR NORTH AND CLOSER TO
5 DEGREES ACROSS THE METRO PHILLY AREAS AND OVER THE DELMARVA. HIGH
TEMPS SUNDAY IN THE TEENS MOST AREAS...BUT SINGLE DIGITS OVER THE
SRN POCONOS. WIND CHILL READINGS -20 TO -32 FAR NORTH AND -5 TO -10
OVER THE DELMARVA.
THE NEXT STORM SYSTEM WILL DEEPEN ACROSS THE SOUTH MONDAY AND MOVE
UP THE INLAND EAST COAST TUESDAY/WEDNESDAY. THE TRACK OF THE SYSTEM
THAT SEEMS TO BE COMING INTO BETTER AGREEMENT AMONGST THE OP MODELS
FAVOR A LOW TRACK ACROSS THE CENTRAL/WESTERN PART OF OUR AREA. THIS
WILL ALLOW A DECENT FLOW OF WARMER AIR TO OVERSPREAD THE REGION. THE
PRECIPITATION WILL BEGIN ACROSS THE AREA MONDAY AS SNOW...BUT WILL
CHANGE TO RAIN LATER MON NIGHT AND REMAIN MOSTLY RAIN TUESDAY. THE
QPF COULD BE UP TO 2 INCHES OF RAIN IN MANY AREAS. THERE IS ALSO
SOME CHC FOR AN ACCUMULATING SNOW MONDAY ACROSS (MOST LIKELY)
ERN/NERN PA BEFORE THE CHANGE TO RAIN. EARLIEST PREDICTIONS FOR SNOW
ACCUMS WOULD BE AROUND 1-3 INCHES AT THIS POINT. THE DETAILS WILL BE
TUNED UP AS THE WEEKEND PROGRESSES.
THE STORM MOVES UP INTO CANADA WEDNESDAY AND WILL BE FOLLOWED BY HIGH
PRESSURE AND DRIER COOLER AIR FOR THE MIDDLE OF NEXT WEEK.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
THIS EVENING...VFR CONDITIONS WILL CONTINUE WITH LIGHT SOUTH TO
SOUTHWEST WINDS ACROSS THE TERMINALS.
TONIGHT THROUGH EARLY SATURDAY MORNING...A COLD FRONT WILL APPROACH
THE REGION FROM THE WEST. AN AREA OF SNOW SHOWERS LOOKS TO DEVELOP
IN ADVANCE OF THE FRONTAL PASSAGE AND SNOW SHOWERS ARE EXPECTED TO
REACH ALL TERMINALS. VISIBILITIES AND CEILINGS ARE EXPECTED TO DROP
TO MVFR CONDITIONS AS THE SNOW SHOWERS MOVE THROUGH. ONCE THE
SHOWERS CLEAR THE REGION, BETWEEN 05-09Z FROM WEST TO EAST, A RETURN
TO VFR CONDITIONS IS ANTICIPATED. SNOW SHOWERS MAY DISSIPATE BEFORE
FULLY REACHING KACY AND KMIV BUT LATEST GUIDANCE LEADS US TO INCLUDE
THE SNOW SHOWERS FOR LATE TONIGHT/EARLY SATURDAY.
SATURDAY...THE BIGGEST ISSUE AFFECTING AVIATION TRAVEL ON SATURDAY
WILL BE THE WINDS. BEHIND THE AFOREMENTIONED COLD FRONT, THE WINDS
WILL QUICKLY TURN TO THE WEST THEN NORTHWEST AND BECOME VERY GUSTY.
SUSTAINED WINDS WILL BE AROUND 15-20 KNOTS BY 12-15Z AND INCREASE
INTO THE AFTERNOON. WIND GUSTS FROM 25 KNOTS EARLY WILL INCREASE TO
NEAR 40 KNOTS BY THE AFTERNOON.
OUTLOOK...
SATURDAY NIGHT AND SUNDAY...VFR CONDITIONS EXPECTED. NORTHWEST
WINDS 10 TO 25 KNOTS WITH GUSTS 30-35 KNOTS EARLY, DIMINISHING
SOME OVERNIGHT INTO SUNDAY. GUSTS STILL 20-25 KNOTS OVERNIGHT INTO
EARLY SUNDAY.
MONDAY-MONDAY NIGHT...DEGRADING CONDITIONS WITH MVFR/IFR LIKELY
THROUGH THE DAY MONDAY INTO MONDAY NIGHT. SNOW POSSIBLY
BEGINNING MONDAY FOR MANY AREAS, POSSIBLY MIXING WITH RAIN AT
TIMES FOR SOME AREAS.
TUESDAY-TUESDAY NIGHT...WIDESPREAD MVFR/IFR CONDITIONS. WINDY.
WEDNESDAY...IMPROVING CONDITIONS. WINDY.
&&
.MARINE...
LULL IN THE WIND AND SEAS WILL END SHORTLY AFTER MIDNIGHT.
GALES AND FREEZING SPRAY WARNINGS-ADVISORIES POSTED. THE HEAVIEST
FREEZING SPRAY WILL BE MIDNIGHT TO 7 AM ALONG THE SHORE WHERE SSTS
NOW DOWN TO ABOUT 35-36F AND USED 35 FOR THE ZY THRESHOLD.
ISOLATED 50 KT GUSTS POSSIBLE SATURDAY IN FUNNELED NW WIND DOWN DE
BAY.
OUTLOOK...
SATURDAY-SATURDAY NIGHT...GALE WARNING CONTINUES WITH STRONG
NORTHWEST FLOW ACROSS THE AREA. FREEZING SPRAY ADVISORY REMAINS IN
EFFECT AS VERY COLD AIR AND STRONG WINDS WILL LEAD TO AT LEAST
MODERATE FREEZING SPRAY.
SUNDAY-SUNDAY NIGHT...GALE WARNING AND FREEZING SPRAY ADVISORY
CONTINUE INTO SUNDAY MORNING. HOWEVER, WINDS WILL DIMINISH THROUGH
THE DAY AND SUNDAY NIGHT AS HIGH PRESSURE BUILDS INTO THE AREA.
MONDAY...SUB-SCA CONDITIONS.
MONDAY NIGHT-WEDNESDAY...SMALL CRAFT ADVISORY CONDITIONS
LIKELY...GALES POSSIBLE AS STRONG LOW PRESSURE MOVES UP THE EAST
COAST.
&&
.HYDROLOGY...
BEFORE EVERYONE HEADS INTO THE WEEKEND, I WANTED TO BRING NEXT
WEEK`S STORM INTO LIGHT AND MENTION THAT THERE IS A POTENTIAL FOR
FLOODING ACROSS THE HSA. THERE`S STILL A LOT THAT NEEDS TO UNFOLD,
BUT THE 5-DAY WPC QPF OF 1.50 TO 2.50 INCHES OF LIQUID COMBINED WITH
ANOTHER 0.25 TO 0.50 INCH OF SWE ON THE GROUND WOULD VERY LIKELY
CAUSE NUISANCE LOW-LYING FLOODING AND POSSIBLY SOME MINOR TO
MODERATE RIVER FLOODING (RIVERS ASSOCIATED WITH OUR FORECAST
POINTS). THIS ASSUMES MOST, IF NOT ALL, THE PRECIPITATION FALLS AS
RAIN.
THE UNCERTAINTY THIS AFTERNOON IS LARGE. YESTERDAY AT THIS TIME, THE
PRECIPITATION WAS HEAVIEST TUESDAY AND TUESDAY NIGHT. NOW IT`S LATE
MONDAY NIGHT INTO TUESDAY. BESIDES TIMING, TRACK IS QUITE DIFFERENT
BETWEEN THE GFS AND EURO WITH THE EURO BEING FURTHER WEST AND MORE
LIQUIDY. TRACK WILL PLAY A ROLE IN TEMPS AND NOT ONLY AFFECT WHAT
TYPE OF PRECIPITATION FALLS, BUT ALSO AFFECT WHAT REMAINING SWE
MELTS. THERE`S ABOUT 0.25 TO 0.50 SCATTERED ACROSS THE AREA. I CAN
SAY WE ARE IN A BETTER SPOT THAN ON THE 3RD AND 4TH WHEN THERE WAS
IN EXCESS OF 2.00 OF SWE ALONG THE I-78 CORRIDOR. AS AN FYI, ONE OF
THE MAIN REASONS WE DIDN`T SEE THE FLOODING, THAT MODELS SUGGESTED,
ON THE 3RD AND 4TH WAS BECAUSE ALL THE SWE DID NOT RAPIDLY COME OUT
OF THE SNOWPACK. SNOWMELT CAN BE A TOUGH NUT TO CRACK.
WHILE THE LACK OF SWE IS LOOKING BETTER ACROSS THE HSA, NOT ALL THE
RIVERS HAVE RECEDED BACK TO WHERE THEY WERE PRIOR TO THE 3RD. SO
RIVERS WILL START HIGHER AND THE COLD THIS WEEKEND WILL SURELY GET
THE GROUND HARD FOR A VERY EFFICIENT RUNOFF.
SO THE TAKE AWAY HEADING INTO THE WEEKEND IS TO UNDERSTAND THAT IF
THE MONDAY INTO TUESDAY (OR TUESDAY INTO WEDNESDAY) EVENT IS ALL
LIQUID ACROSS THE AREA, LOW-LYING, POOR DRAINAGE FLOODING IS LIKELY
AND MINOR TO MODERATE RIVER FLOODING IS POSSIBLE. IF THE
PRECIPITATION STARTS OFF AS SNOW OR ICE, THE FLOODING THREAT
DECREASES. IF ALL SNOW FALLS, WE`RE POTENTIALLY JUST KICKING THE CAN
DOWN THE ROAD FOR FUTURE FLOODING. TIME WILL TELL.
&&
.CLIMATE...
NEAR RECORD COLD IS STILL EXPECTED FOR PORTIONS OF OUR AREA SUNDAY
MORNING, DESPITE THE MOS GUIDANCE...AND BY FAR THE COLDEST AIR OF
THE SEASON SO FAR.
BEST CHANCE FOR RECORD EQUALING OR EXCEEDING FOR VALENTINES DAY:
KABE, KTTN, KPHL AND KMPO.
RECORD LOW MAX`S CAN ONLY OCCUR FOR THIS EVENT ON SUNDAY THE 14TH,
IF THEN. THOSE HAVE BEEN ADDED RECENTLY BELOW.
SITE 2015-16 COLDEST SO FAR RECORD LOW FEB. 14TH ----RER LOW MAX
---------------------- --------------------
ABE 8 -1 IN 1979 14-1979
ACY 10 -6 IN 1979 13-1979
PHL 12 +2 IN 1979 14-1979
ILG 12 -4 IN 1979 13-1979
RDG 10 -4 IN 1983
TTN 9 0 IN 1916
GED 13 -7 IN 1979
MPO -1 -12 IN 1970
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WIND CHILL ADVISORY FROM 6 PM SATURDAY TO 9 AM EST SUNDAY FOR
PAZ060>062-070-071-101>106.
WIND ADVISORY FROM 6 AM TO 6 PM EST SATURDAY FOR PAZ054-055-
060-061-070-071-101>106.
WIND CHILL WARNING FROM 6 AM SATURDAY TO 1 PM EST SUNDAY FOR
PAZ054-055.
NJ...WIND CHILL ADVISORY FROM 6 PM SATURDAY TO 9 AM EST SUNDAY FOR
NJZ007>010-012>027.
WIND ADVISORY FROM 6 AM TO 6 PM EST SATURDAY FOR NJZ001-014-
016>027.
WIND CHILL WARNING FROM 6 AM SATURDAY TO 1 PM EST SUNDAY FOR
NJZ001.
DE...WIND CHILL ADVISORY FROM 6 PM SATURDAY TO 9 AM EST SUNDAY FOR
DEZ001-002.
WIND ADVISORY FROM 6 AM TO 6 PM EST SATURDAY FOR DEZ001>004.
MD...WIND CHILL ADVISORY FROM 6 PM SATURDAY TO 9 AM EST SUNDAY FOR
MDZ008-012.
WIND ADVISORY FROM 6 AM TO 6 PM EST SATURDAY FOR MDZ008-012-
015-020.
MARINE...HEAVY FREEZING SPRAY WARNING FROM MIDNIGHT SATURDAY NIGHT TO 9
AM EST SUNDAY FOR ANZ450>453.
GALE WARNING FROM 4 AM SATURDAY TO 10 AM EST SUNDAY FOR ANZ430-
431-450>455.
FREEZING SPRAY ADVISORY FROM 4 AM SATURDAY TO 10 AM EST SUNDAY
FOR ANZ430-431-454-455.
&&
$$
SYNOPSIS...O`HARA
NEAR TERM...DRAG 4P
SHORT TERM...DRAG 4P
LONG TERM...O`HARA
AVIATION...DRAG/O`HARA 4P
MARINE...DRAG/O`HARA 4P
HYDROLOGY...
CLIMATE...
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
255 PM CST FRI FEB 12 2016
.SHORT TERM...(Tonight)
ISSUED AT 255 PM CST FRI FEB 12 2016
A weak clipper system will exit southeast of central IL late this
afternooon, with its diminishing area of very light snow/flurries se
of the IL river ending soon, with best light snow chances east of IL
over central IN. MVFR clouds already scattering nw of the IL river
like at PIA and HRRR model handling this clearing well. These clouds
to decrease se of the IL river during late afternoon/early evening,
and over southeast IL by mid evening. Brisk NW winds of 15-25 mph
and gusts to 30 mph will gradually diminish during the night,
reaching 5-15 mph later tonight. Strong 1046 mb polar high pressure
west of Lake Winnipeg Canada to settle se into MN/IA by sunrise Sat
and bring a frigid night to the region. Lows by early Saturday
morning range from around zero north of I-72 to 4-8F in southeast IL
from I-70 southeast. Wind chills by dawn will range from 5-15 below
zero with a few spots from I-74 north dipping to 15-17 below zero
like at Bloomington, Galesburg and Champaign. Will hold off on a
wind chill advisory overnight into mid Sat morning, but will issue
SPS to address these bitter cold wind chills especially in our
northern CWA.
&&
.LONG TERM...(Saturday through Friday)
ISSUED AT 255 PM CST FRI FEB 12 2016
Very cold conditions expected to start the day Saturday across
central and southeast Illinois as Arctic high pressure builds across
the area. The relatively slight pressure gradient that will
accompany the surface high should keep Wind Chill values warmer than
advisory criteria for the most part, but high temperatures should
only top out in the teens.
Beyond the initially cold conditions, our attention turns to an
approaching clipper system, which is likely to be the most
significant weather system to impact the area over the next week.
This clipper has trended faster in recent model runs, with snow now
expected to start breaking locally after midnight Saturday
night/Sunday morning. The system will be pushing into a very dry
airmass which should limit the snow accumulation to some degree.
However, fairly strong isentropic ascent and mixing ratios of 2-3
G/KG over at least a 12 hour period should be able to produce 2"=4"
snow totals. In fact, would not be surprised if we need to boost
accumulations further once the exact track of the system is more
clear (it has trended s bit south in the latest runs). One other
thing that will need to be monitored is that the moisture depth is
progged to be rather shallow during the period of potential snow.
This fact is also a reason to limit snow accumulations for now, and
we also need to monitor the threat for freezing drizzle due to a
potential lack of ice crystals.
The faster trend of the clipper system should now have Monday ending
up dry. Another weak clipper system may impact the area Tuesday into
Tuesday night, but it does not appear significant at this time.
After that, the next chance for precipitation should not occur
before the end of the week. However, model agreement in the details
of the late week system is weak at best. Temperatures should
gradually be trending warmer next week, with well above normal
temperatures likely by the end of the week (near 50 degrees for
highs). If these trends hold, the late week system, if/when it
impacts the area, should be a rain producer.
&&
.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
ISSUED AT 1155 AM CST FRI FEB 12 2016
A weak clipper system was bringing a band of light snow and
flurries that was progessing se of the IL river and approaching
I-72 at midday. The light snow was bringing vsbys down to 1-3
miles for 1-2 hours at PIA and will affect BMI and CMI next few
hours and possibly briefly bring MVFR vsbys to DEC early this
afternoon. MVFR ceilings are expected to scattered out from nw to
se late this afternoon and early evening. Brisk NW winds of 13-18
kts and gusts of 18-25 kts into this evening will diminish to
around 10 kts by overnight and down to 5-9 kts late tonight into
Saturday morning. 1046 mb arctic high pressure west of Lake
Winnipeg Canada will settle into eastern IA by 18Z/noon Sat as it
weakens a bit to 1041 mb. This will provide the fair weather
tonight into Sat with winds diminishing as high pressure settles
in.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...07
LONG TERM...BAK
AVIATION...07
AREA FORECAST DISCUSSION
NWS GRAY ME
348 PM EST FRI FEB 12 2016
.SYNOPSIS...
AN ARCTIC COLD FRONT WILL CROSS THE REGION TONIGHT THROUGH SATURDAY
USHERING IN THE COLDEST AIRMASS OF THE SEASON THUS FAR. AS THIS
COLD AIR INTERACTS WITH A TROUGH OF LOW PRESSURE OVER THE GULF OF
MAINE...A PERIOD OF MODERATE TO HEAVY SNOW WILL BE POSSIBLE ALONG
THE MIDCOAST REGION OF MAINE. BEYOND THIS...THE COMBINATION OF COLD
TEMPERATURES AND STRONG NORTHWEST WINDS WILL CAUSE DANGEROUSLY COLD
WIND CHILLS SATURDAY NIGHT AND SUNDAY. TEMPERATURES WILL RAPIDLY
MODERATE NEXT WEEK WITH A WINTRY MIX OF PRECIPITATION POTENTIALLY
TRANSITIONING TO RAIN ON MONDAY NIGHT AND TUESDAY ALONG WITH STRONG
SOUTHERLY WINDS.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
HIGH IMPACT WEATHER POTENTIAL: SNOW DEVELOPS ALONG THE MIDCOAST
OVERNIGHT.
CURRENT PATTERN: EARLY AFTERNOON WATER VAPOR IMAGERY REVEALS RIDGE-
TROUGH PATTERN ACROSS THE CONUS...WITH IMPRESSIVE PORTION OF THE
POLAR VORTEX CURRENTLY CENTERED OVER JAMES BAY. SOUTH OF THIS
FEATURE...WATER VAPOR IMAGERY DEFINES A DIGGING SHORTWAVE /DARKENING
OF THE IMAGERY/ OVER THE NORTHERN OHIO VALLEY. THIS WILL HELP FORCE
CYCLOGENESIS OFF THE MID ATLANTIC COAST THAT WILL RACE NORTHEAST
WELL SOUTH AND EAST OF NEW ENGLAND THROUGH SATURDAY. A WEAKER
SURFACE LOW IS CURRENTLY DEPICTED OVER THE EASTERN GREAT LAKES
ASSOCIATED WITH FORCING AHEAD OF THE H5 LOW OVER JAMES BAY. AS THIS
LATTER FEATURE DIVES SOUTH AND EAST TOWARDS NEW ENGLAND THIS
WEEKEND...THE ASSOCIATED SURFACE LOW WILL BE ABSORBED INTO THE
DEVELOPING SYSTEM OFFSHORE. OUR PRIMARY WEATHER IMPACTS WILL BE
1- WHAT HAPPENS BETWEEN THESE SYSTEMS AS IMPRESSIVE MID AND UPPER
LEVEL FORCING COMBINES WITH VERY SUBSTANTIAL INSTABILITY OVER THE
RELATIVELY WARM GULF OF MAINE WATERS AND 2- THE RAMIFICATIONS OF
ARRIVING ARCTIC AIR. TEMPS AT H8 THIS MORNING WERE -35C OVER JAMES
BAY WITH TEMPERATURES CLOSE TO THIS REACHING NEW ENGLAND ON
SATURDAY...PRESENTING WIND CHILL CONCERNS AS IMPRESSIVE COLD
ADVECTION DRIVES THIS AIR INTO THE REGION.
TONIGHT: EXPECT A GENERAL INCREASE IN MID AND UPPER LEVEL
CLOUDINESS PER A LOOK AT AFTERNOON VISIBLE SATELLITE IMAGERY AS
WEAK WARM ADVECTION CONTINUES AHEAD OF APPROACHING SURFACE LOW NOW
NORTH OF LAKE ONTARIO. FORCING FOR ASCENT WILL BE ON THE INCREASE
WITH TOP DOWN SATURATION LIKELY BRINGING SNOW SHOWER ACTIVITY INTO
THE MOUNTAINS OVERNIGHT. WE/LL TALK MORE ABOUT THE NORLUN EVENT IN
THE SHORT TERM SECTION BELOW...BUT EXPERIMENTAL HRRR IS ON BOARD
WITH THE 12Z GUIDANCE SUITE IN DEVELOPING LLEVEL CONVERGENCE IN THE
VICINITY OF PENOBSCOT BAY BY MIDNIGHT TONIGHT...WITH SNOW DEVELOPING
IN THIS REGION AND CONTINUING THROUGH THE MORNING. WITH A GOOD
FLUFF FACTOR HELPING ACCUMULATIONS...COULD SEE 1-3 INCHES OVER
KNOX/WALDO COUNTIES BY DAYBREAK.
TEMPERATURES: WITH SOUTHWEST FLOW ONGOING AND CLOUDS ON THE
INCREASE...TEMPERATURES WILL BE A GOOD BIT WARMER THAN THE PREVIOUS
NIGHT BUT GIVEN THE CHILLY HIGHS OF TODAY...WILL CERTAINLY NOT BE
WARM. EXPECT LOWS IN THE SINGLE DIGITS IN THE MOUNTAINS THROUGH THE
LOWER TEENS ALONG THE COAST.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
...SIGNIFICANT SNOW ALONG THE MID COAST BECOMING INCREASINGLY
LIKELY SATURDAY...
...DANGEROUSLY COLD WIND CHILLS SATURDAY NIGHT THROUGHOUT THE
REGION...
HIGH IMPACT WEATHER POTENTIAL: HEAVY SNOW TOTALS POSSIBLE IN THE
VICINITY OF PENOBSCOT BAY SATURDAY WITH ATTENTION THEN TURNING TO
ADVISORY-WARNING LEVEL WIND CHILLS SATURDAY NIGHT.
SATURDAY: CORE OF H5 LOW ALOFT SINKS FROM JAMES BAY AT DAYBREAK
SOUTH AND EAST INTO NORTHERN NEW ENGLAND TOWARDS EVENING WITH T8S
NEARING -30C OVER MY WESTERN ZONES BY 00Z/SUN. COL REGION BETWEEN
LOW LEVEL REFLECTION OF THIS H5 LOW AND THE DEVELOPING SYSTEM WELL
SOUTH AND EAST OF THE BENCHMARK APPEARS TO BE ALLOWING ALL THE
INGREDIENTS FOR A BONA-FIDE NORLUN EVENT TO BE PRESENT AS THE H8
FLOW GOES SLACK ALONG WITH A DEVELOPING LLEVEL CONVERGENCE ZONE.
THERE WILL BE AMPLE INSTABILITY IN THE LLEVELS WITH WATER SURFACE TO
H8 DELTA TS NEAR -15 AND DELTA TS TO H7 NEARING -30C. THIS ALLOWS
FOR A TREMENDOUS AMOUNT OF LLEVEL INSTABILITY...WITH OCEAN-INDUCED
CAPE VALUES OF 500-1000 J/KG PORTRAYED ON THE 12Z NAM AND GFS.
THIS COULD VERY WELL PROMOTE THUNDER WITH ANY SNOW BAND THAT DOES
DEVELOP.
SNOW RATIOS: THE DENDRITIC GROWTH ZONE WILL BE BELOW THE PRIMARY
AREA OF LIFT DURING THE HEIGHT OF THE EVENT...BUT IT WILL STILL GET
CLIPPED AND SEE NO REASON WHY WE CAN/T FORCE 15-20:1 RATIOS OUT OF
THIS SETUP.
THERE IS UNCANNY AGREEMENT IN THE 12Z SUITE /NAM-GFS-ECMWF-GEM/ ON
THE PLACEMENT OF THE MESOSCALE BAND OVER PENOBSCOT BAY. WHILE THIS
WOULD TEND TO SUGGEST ABOVE NORMAL CONFIDENCE...THE FACT THAT THIS
IS A NORLUN EVENT BEGS CAUTION. A LOOK A THE 00Z NCAR ENSEMBLE
SHOWS ABOUT 40% OF THE MEMBERS DIRECTLY IMPACTING OUR AREA. WOULD
REALLY LIKE TO SEE THIS EVENT COME INTO THE NEAR TERM-HIGH
RESOLUTION GUIDANCE WINDOW AND AS SUCH...WITH THE WORD OUT RIGHT NOW
WITH THE WATCH...WILL LET THE EVENING SHIFT TAKE A FINAL LOOK AT
THINGS BEFORE MAKING A FINAL DECISION ON WINTER STORM WARNINGS VS.
WINTER WEATHER ADVISORIES. THAT BEING SAID...CERTAINLY CANNOT RULE
OUT SOME 1 FOOT+ SNOWFALL AMOUNTS SOMEWHERE IN THE MID COAST REGION
GIVEN THE SETUP ABOVE.
TEMPERATURES: MAY RISE SLIGHTLY IN THE EARLY MORNING...BUT WILL
THEN REVERSE COURSE AND FALL THROUGH THE AFTERNOON WITH ALL
LOCATIONS IN THE SINGLE DIGITS ABOVE AND BELOW ZERO BY EVENING. WIND
CHILLS WILL REACH ADVISORY LEVELS IN THE MOUNTAINS IN THE
AFTERNOON...WITH THE MOST DANGEROUS VALUES HOLDING OFF UNTIL
SATURDAY NIGHT. NONETHELESS...WIND CHILLS WILL BECOME
INCREASINGLY DANGEROUS BY LATE AFTERNOON/EVENING.
WINDS: VERY IMPRESSIVE COLD AIR ADVECTION WILL YIELD STEEP LLEVEL
LAPSE RATES...WHICH SHOULD BE ABLE TO MIX ANYTHING THE ATMOSPHERE
HAS TO OFFER WIND-WISE IN THE LOWEST 5KFT. HIGHEST WINDS IN THE
COLUMN ARE AROUND 30KTS /A BIT HIGHER OFFSHORE/ SO WILL PAINT GUSTS
AROUND 30MPH INLAND /HIGHER ON THE HILLTOPS/ AND 30-40MPH ALONG THE
COAST. NOTE: WINDS WILL NOT BE THIS STRONG IN THE VICINITY OF THE
NORLUN TROUGH AND THUS SIGNIFICANT BLOWING/DRIFTING WILL NOT
INITIALLY BE A PROBLEM. HOWEVER...BY SATURDAY EVENING...THERE
WILL LIKELY BE SIGNIFICANT BLOWING/DRIFTING...AND WILL HAVE TO
WATCH FOR THIS IF THE SNOW DOES MATERIALIZE.
SATURDAY NIGHT: H5 LOW OPENS UP AND SHIFTS EAST WITH THE CORE OF THE
COLDEST AIR ALOFT OVERHEAD UNDER CONTINUED STRONG NORTHWEST WINDS AS
GRADIENT BETWEEN 1035 MB HIGH OVER THE GREAT LAKES COMBINES WITH
OFFSHORE-MOVING NORLUN TO CONTINUE WINDS OF 15G25KTS. CONCERNS WILL
TURN TO DANGEROUSLY COLD WIND CHILLS...WHICH SHOULD HAVE NO PROBLEM
HITTING WARNING CRITERIA IN THE MOUNTAINS AND FOOTHILLS...BUT LIKELY
REMAIN AT ADVISORY LEVELS ALONG THE COAST. AM HONESTLY A BIT
SURPRISED IN THE MET/MAV LOW TEMPERATURE SPREAD AS WE SHOULD
REMAIN WELL-MIXED THROUGH THE NIGHT. DID GIVE SOME NOD TO THE
COLDER MET...WITH LOWS BELOW ZERO IN ALL LOCATIONS...AND PERHAPS
AS LOW AS -20 IN THE MOUNTAINS.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH IMPACT WEATHER: DANGEROUSLY COLD WIND CHILLS LINGER INTO AT
LEAST SUNDAY MORNING. A STORM COULD BRING SNOW/FREEZING RAIN/RAIN
TO THE REGION MONDAY NIGHT INTO TUESDAY NIGHT. STRONG WINDS ARE
POSSIBLE WITH THIS SYSTEM AS WELL.
DEEP PERSISTENT 500 TROUGH OVER THE ERN CONUS ON SUNDAY WILL SHIFT
NE AND WEAKEN BY EARLY NEXT WEEK...AND THIS ALLOWS THE HEMISPHERIC
WAVE PATTERN TO BECOME LESS AMPLIFIED WITH A HIGHER WAVE NUMBER.
THE OVERALL +PNA PATTERN WEAKENS EARLY TO MID-WEEK...AND TRIES TO
BREAK DOWN BY THE END OF THE WEEK. OF NOTE THOUGH...IS SRN STREAM
WAVE THAT DIGS OVER S CENTRAL CONUS MON AND LIFTS NWD TUE AND WED
AS NRN STREAM DIVES INTO IT AND THIS COULD PRODUCE THE HIGH IMPACT
STORM OVER NEW ENGLAND AROUND TUESDAY.
SUNDAY START IN THE THROES OF THE THE VERY COLD AIR MASS IN THE
REGION WITH STRONG PRES GRAD IN PLACE AND GUSTY NW WINDS. THE
DANGEROUS WIND CHILLS LINGER THRU THE MORNING BUT AS TEMPS WARM
FROM LOWS BELOW ZERO EVERYWHERE...AND WITH PRES GRADIENT
SLACKENING AS SFC HIGH BUILDS IN SHOULD SEE WIND CHILLS RISE TO
MORE BEARABLE LVLS BY AFTERNOON. STILL...THE TAIL OF THE CAA WILL
HOLD THRU MOST OF THE DAY AND HIGHS WILL STRUGGLE TO REACH ZERO IN
THE N...AND TO REACH 10F IN THE SOUTH. AS THE SFC HIGH MOVES OVER
THE REGION LOOK FOR DECOUPLING IN MOST PLACES AND VERY GIVEN GOOD RAD
COOLING GIVEN COLD AIR IN PLACE AND A STARTING POINT NEAR OR BELOW
ZERO. WENT BELOW SUPERBLEND FOR MINS IN MOST PLACES...AND
SIGNIFICANTLY BELOW IN THE MORE SHELTERED SPOTS. THIS SHOULD BRINGUS
LOWS 10 BELOW TO ZERO IN THE COASTAL PLAIN...WITH LOWS DROPPING
TO -20 OR LOWER IN THE SHELTERED MOUNTAIN VALLEYS.
ON MONDAY LOOK FOR WARMER AIR TO START WORKING IN...AND HIGHS
REBOUND INTO THE TEENS TO MID 20S...WITH INCREASING CLOUDS IN THE
AFTERNOON.
THE NEXT SYSTEM MOVES IN ON MON NIGHT AND TUE. SOME DIFFERENCES IN
THE MODEL AS TO HAVE FAR W THE SFC LOW TRACKS...WITH THE GFS AND
GGEM PASSING IT S-N THRU THE MIDDLE OF ME...AND THE EURO AND GEFS
MEAN BRINGING IT NWD ALONG THE NY/VT BORDER...WHICH WOULD BE THE
WARMER SOLN...AND LIKELY LEAD TO SNOW TO FZRA/PL TO RAIN SOLN IN
MANY SPOTS. THE MORE EASTERLY TRACK WOULD SEE SNOW LAST LONGER
INTO THE STORM AWAY FROM THE COAST. P-TYPE WILL BE ONE OF THE BIG
ISSUES WITH THIS SYSTEM AND CONFIDENCE IS LOW AS TO HOW IT WILL
ALL UNFOLD. ONE THING TO NOTE IS THAT WE ARE COMING OUT OF VERY
COLD AIRMASS...AND DESPITE THE BEST WINDS ABOVE THE INVERSION IT
WILL BE SLOW TO BREAK OUT OF THAT LOW LVL COLD AIR...WHICH WILL
PROBABLY HOLD ON LONGER THAN THE MODELS SUGGEST. ANOTHER ISSUE
COULD BE STRONG WINDS...ALTHOUGH WITH THE INVERSION MAY BE TOUGH
FOR THOSE WINDS TO MIX TO THE SFC...AT LEAST FOR ANY SIGNIFICANT
LENGTH OF TIME.
THE WHOLE SYSTEM WILL MOVE OUT LATE TUE NIGHT AND WED. COULD BUST
OUT INTO WARMER AIR ON WED BEHIND THE SYSTEM WITH HIGHS CLIMBING
INTO THE UPPER 30S TO LOW 40S. COLD FRONT SWINGS THRU WED NIGHT
WITH UPPER LVL TROUGH ON THU AND TEMPS DROP BACK AGAIN...BELOW
NORMAL...BUT NOT TOO FAR...WITH HIGHS IN THE 20S TO AROUND 30.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
SHORT TERM...VFR UNDER MOSTLY CLEAR CONDITIONS ATTM. EXPECT
DETERIORATING CONDITIONS THROUGH THE COMING TAF PERIOD WITH SNOW
DEVELOPING OVERNIGHT AT RKD AND LIKELY AUG WITH IFR/LIFR
RESTRICTIONS. FOR A PERIOD SATURDAY...INCH PER HOUR SNOWFALL RATES
ARE POSSIBLE...MOST LIKELY AT RKD. FURTHER WEST...ARCTIC FRONT
WILL BRING A ROUND OF SNOW SHOWERS...MOST LIKELY TO BRING
RESTRICTIONS TO LEB/HIE...BUT BRIEF RESTRICTIONS ARE POSSIBLE
SOUTH AND EAST OF THIS AS WELL. CONDITIONS IMPROVE SATURDAY NIGHT
WITH VFR CONDITIONS RETURNING FOR SUNDAY.
AFTER LIGHT WINDS OVERNIGHT...STRONG NORTHWEST WINDS /15G25KTS/
WILL DEVELOP BY LATE MORNING SATURDAY AND CONTINUE THROUGH
SATURDAY NIGHT.
LONG TERM...MAINLY VFR SUN THRU MON WITH GUSTY NW WINDS
DIMINISHING DURING SUN AFTERNOON. COULD SEE EXTENDED PERIOD OF
IFR OR LOWER IN SN/FZRA/RA MON NIGHT INTO TUE NIGHT.
&&
.MARINE...
SHORT TERM...WINDS/WAVES BELOW SMALL CRAFT LEVELS INTO TOMORROW
MORNING BEFORE INTENSE COLD ADVECTION BEHIND AN ARCTIC COLD FRONT
BRINGS A PERIOD OF GALES TO THE OUTER WATERS BY LATE SATURDAY
AFTERNOON THROUGH SUNDAY MORNING WITH WINDS LIKELY REMAINING BELOW
GALE FORCE IN THE BAYS. IN ADDITION...HEAVY FREEZING SPRAY
WARNINGS HAVE BEEN HOISTED SATURDAY EVENING THROUGH SUNDAY MORNING
GIVEN THE COMBINATION OF THE AFOREMENTIONED WINDS AND THE COLDEST
AIRMASS OF THE SEASON THUS FAR.
LONG TERM...NW WIND DIMINISH SLOWLY THRU SUNDAY...AS DOES
INTENSITY OF FREEZING SPRAY...BUT WILL LKLY HOLD TO SCA WINDS
THRU SUN EVE. AFTER A BRIEF BREAK IN THE WINDS ON MON AND MON
NIGHT...LOOK FOR S WINDS TO REACH SCA LVLS EARLY TUE AND COULD
REACH GALES BY TUE AFTERNOON AND EVE...BEFORE DIMINISHING WED.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WIND CHILL WARNING FROM MIDNIGHT SATURDAY NIGHT TO 10 AM EST
SUNDAY FOR MEZ012>014-018>022.
WIND CHILL WARNING FROM 7 PM SATURDAY TO 10 AM EST SUNDAY FOR
MEZ007>009.
WIND CHILL ADVISORY FROM MIDNIGHT SATURDAY NIGHT TO 10 AM EST
SUNDAY FOR MEZ023>028.
WINTER STORM WATCH FROM MIDNIGHT EST TONIGHT THROUGH SATURDAY
EVENING FOR MEZ022-027-028.
NH...WIND CHILL WARNING FROM MIDNIGHT SATURDAY NIGHT TO 10 AM EST
SUNDAY FOR NHZ004>013-015.
WIND CHILL WARNING FROM 7 PM SATURDAY TO 10 AM EST SUNDAY FOR
NHZ001>003.
WIND CHILL ADVISORY FROM MIDNIGHT SATURDAY NIGHT TO 10 AM EST
SUNDAY FOR NHZ014.
MARINE...HEAVY FREEZING SPRAY WARNING FROM 7 PM SATURDAY TO 10 AM EST
SUNDAY FOR ANZ150>154.
SMALL CRAFT ADVISORY FROM NOON SATURDAY TO 10 AM EST SUNDAY
FOR ANZ151-153.
GALE WARNING FROM 4 PM SATURDAY TO 10 AM EST SUNDAY FOR ANZ150-
152-154.
&&
$$
SYNOPSIS...ARNOTT
NEAR TERM...ARNOTT
SHORT TERM...ARNOTT
LONG TERM...CEMPA
AVIATION...ARNOTT/CEMPA
MARINE...ARNOTT/CEMPA
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
548 PM EST FRI FEB 12 2016
.SYNOPSIS...
AN ARCTIC FRONT WILL BRING SNOW SHOWERS TO THE AREA THROUGH
SATURDAY. MUCH COLDER TEMPERATURES AND DANGEROUS WIND CHILLS WILL
CONTINUE INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH SATURDAY/...
BASED ON LATEST OBSERVATIONS AND RADAR TRENDS CURRENT TIMING OF
POTENTIAL SQUALL CONDITIONS STILL LOOKS GOOD AS WV IMAGERY SHOWS
THE JET CORE ROUNDING THE BASE OF THE LONGWAVE PIVOTING OVER THE
AREA. NOT MUCH CHANGE IS NEEDED AT THIS TIME TO THE ONGOING
FORECAST OTHER THAN MINOR ADJUSTMENTS TO HOURLY TEMPERATURES.
PREV DISCUSSION FOLLOWS..
SHORTWAVE PIVOTING ALONG THE BASE OF THE UPPER TROUGH WILL SUPPORT
INCREASING SNOW CHANCES IN THE RIDGES AHEAD OF THE ARCTIC FRONT
PASSAGE PROGGED FOR THIS EVENING/OVERNIGHT. BOTH HI RES AND LONGER
RANGE MODEL SOUNDINGS IN BUFKIT SUGGEST A PERIOD WHERE DEEP
MOISTURE...IN A LAYER FROM ABOUT 600MB TO 850MB...WILL BE WELL
WITHIN THE DENDRITIC GROWTH ZONE. THIS SHOULD SUPPORT EFFICIENT
SNOWFALL FOR A PERIOD...WITH ADDITIONAL SNOW SHOWERS ANTICIPATED
WITH AND BEHIND THE FRONT IN UPSLOPE SNOW UNTIL THE WHOLE BOUNDARY
LAYER FALLS WELL BELOW THE GROWTH ZONE. WITH THIS IN MIND...A
WINTER WEATHER ADVISORY WAS ISSUED FOR THE RIDGES OF PRESTON
TUCKER AND GARRETT COUNTIES THROUGH SATURDAY MORNING.
ELSEWHERE...THE MODEL GUIDANCE HAS CHANGED LITTLE WITH THE TIMING
OF THE SNOW SHOWERS AND POTENTIAL SQUALLS AHEAD OF THE FRONT
PROGGED FOR PASSAGE OVERNIGHT. EXPECT THE LINE TO BE INTO EASTERN
OHIO AND NORTHWESTERN PA BY 00Z AND PITTSBURGH BY 03Z. VARIOUS
RUNS OF THE HRRR AND TO A LESSER DEGREE OTHER SNOW SQUALLS PROGS SUGGEST
THAT THERE WILL BE SOME WEAKENING AS THE LINE COMES ACROSS.
GENERALLY ANTICIPATE A HALF TO AN INCH OF SNOW...WITH SLIGHTLY
HIGHER AMOUNTS NORTH OF PITTSBURGH.
BEHIND THE FRONT...STRONG COLD ADVECTION WILL STEEPEN LAPSE RATES
AND PROVIDE FOR A PERIOD OF GUSTY WINDS AREAWIDE UNTIL LATE
SATURDAY WITH MAXIMUM WIND IN THE BOUNDARY LAYER APPROACHING 25
TO 35KTS. THIS...ADDED TO TEMPERATURES FALLING INTO THE SINGLE
DIGITS WILL LEAD TO WIND CHILL VALUES WELL BELOW ZERO. THIS
SUPPORTS THE WIND CHILL ADVISORY THAT WAS ISSUED. 40MPH WIND
GUSTS OVERNIGHT IN THE RIDGES WILL ALLOW VALUES TO GET VERY CLOSE
TO WARNING CRITERIA BUT AT THIS POINT...THE WATCH HAS BEEN
UPGRADED TO AN ADVISORY WITH SOME -25 VALUES POSSIBLE IN THE
HIGHEST TERRAIN OF TUCKER COUNTY.
IN ADDITION TO THE WIND...LAKE EFFECT SNOW SHOWERS WILL BE
POSSIBLE IN NORTHWEST FLOW WITH MOST IF NOT ALL OF THE MODEL
GUIDANCE SUGGESTING SEVERAL DUAL-LAKE SNOW BANDS. THE LATEST
ITERATION OF MODELS HAS THE MORE PROMINENT BAND SHIFTED SLIGHTLY
SOUTH FROM LAST NIGHT SO WITH UNCERTAINTY IN THE ACTUAL PLACEMENT
OF SNOW BANDS...HAVE OPTED TO UPGRADE THE LAKE EFFECT SNOW WATCH
FOR VENANGO COUNTY TO AN ADVISORY FOR MERCER...VENANGO...AND
FOREST COUNTIES. ADDITIONAL LAKE PLUMES MAY SUPPORT SNOW BEYOND
THESE ADVISORIES THROUGH SATURDAY AFTERNOON...BUT WITH UNCERTAINTY
IN THEIR PLACEMENT...NO ADDITIONAL HEADLINES WERE ADDED.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
LAKE EFFECT SNOW SHOWERS WILL CONTINUE TO TAPER OFF AND SHIFT
NORTHWARD AS A SURFACE RIDGE ATTEMPTS TO BUILD OVERHEAD FOR
SUNDAY. THIS SHOULD ALLOW FOR THE WIND TO BACK OFF...WITH WIND
CHILL CONCERNS DIMINISHING IN OHIO. HOWEVER...WITH THE HIGH
PRESSURE AND LIGHT WIND...TEMPERATURES WILL FALL CLOSE TO OR BELOW
ZERO SATURDAY NIGHT...SO ADVISORIES WILL REMAIN AS IS FOR THE REST
OF THE CWA UNTIL SUNDAY MORNING. TEMPERATURES WILL MODERATE A FEW
DEGREES ON SUNDAY WITH A RETURN OF SOUTHERLY FLOW AND SCATTERING
OF THE CLOUDS. TEMPERATURE FORECAST WAS A BLEND OF GUIDANCE FOR
BOTH PERIODS.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
SHORTWAVE MOVING EAST ACROSS THE GREAT LAKES WILL BRING WARM
ADVECTION ALONG WITH AN INCREASE IN DEEPER MOISTURE SUNDAY NIGHT
INTO MONDAY. THIS WILL GIVE A PERIOD OF SNOW ESPECIALLY SOUTH OF
PITTSBURGH WITH SOME ACCUMULATION EXPECTED. TEMPERATURES LOOK TO
RISE LATER SUNDAY NIGHT AND WILL PUSH TO NEAR THE SEASONAL AVERAGE
MONDAY. BY LATER MONDAY THROUGH TUESDAY A STRONG SOUTHERN STREAM
SHORTWAVE WILL INDUCE LOW PRESSURE ALONG THE GULF COAST WHICH WILL
QUICKLY MOVE ACROSS THE MID ATLANTIC STATES. MODELS STILL DIFFER
ON EXACT TRACK BUT SYSTEM WILL CROSS THE SOUTHERN APPALACHIANS AND
INTENSIFY AS IT MOVES TOWARD NEW ENGLAND BY TUESDAY NIGHT.
POTENTIAL FOR SIGNIFICANT SNOW...BUT ALSO POTENTIAL FOR A MIX WITH
RAIN OR ALL RAIN WHERE BETTER QPF IS FORECAST. FOR NOW HAVE NOT
STRAYED FAR FROM PREVIOUS FORECAST ALTHOUGH EVEN THE WARMER ECMWF
WRAPS COLD AIR BACK IN LATER TUESDAY SO HAVE KEPT MAINLY SNOW.
SYSTEM EXITS TUESDAY NIGHT...BUT WILL BE FOLLOWED BY FAST MOVING
CLIPPER SYSTEM WEDNESDAY WHICH WILL DELIVER ANOTHER PERIOD OF SNOW
SHOWERS FOLLOWED BY A QUICK SHOT OF COLD AIR. HEIGHTS ALOFT THEN
BEGIN TO RISE THURSDAY INTO FRIDAY WITH STRONG WARM
ADVECTION...ESPECIALLY ON FRIDAY.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
LIGHT SNOW HAS DROPPED VSBY TO MVFR OR BELOW FOR A TIME AT KMGW AND
KLBE AS A SHORTWAVE SHIFTS EAST TO THE MID ATLANTIC. SNOW SHOWERS
ALSO WILL DEVELOP AHEAD OF APPROACHING ARCTIC FRONT...WITH MVFR TO
IFR THIS EVENING WITH AND BEHIND THE FRONT. WINDS WILL BE GUSTY OVER
25KTS AND TURNING NORTHWEST WITH AND BEHIND THE FRONT.
.OUTLOOK.../FRIDAY NIGHT THROUGH WEDNESDAY/...
SCATTERED RESTRICTIONS IN SNOW SHOWERS SATURDAY. LOW PRESSURE
SYSTEMS WILL BRING WIDESPREAD RESTRICTIONS LATER SUNDAY NIGHT
THROUGH WEDNESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SUNDAY
FOR MDZ001.
WINTER WEATHER ADVISORY UNTIL 10 AM EST SATURDAY FOR MDZ001.
OH...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 11 AM EST
SATURDAY FOR OHZ039-048-049-057>059-068-069.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SUNDAY
FOR OHZ040-041-050.
PA...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SUNDAY
FOR PAZ007>009-013>016-020>023-029-031-073>076.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST SATURDAY FOR
PAZ007>009.
WV...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 11 AM EST
SATURDAY FOR WVZ003-004-012.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SUNDAY
FOR WVZ001-002-021-509>514.
WINTER WEATHER ADVISORY UNTIL 10 AM EST SATURDAY FOR
WVZ512>514.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
423 PM EST FRI FEB 12 2016
.SYNOPSIS...
AN ARCTIC FRONT WILL BRING SNOW SHOWERS TO THE AREA THROUGH
SATURDAY. MUCH COLDER TEMPERATURES AND DANGEROUS WIND CHILLS WILL
CONTINUE INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH SATURDAY/...
SHORTWAVE PIVOTING ALONG THE BASE OF THE UPPER TROUGH WILL SUPPORT
INCREASING SNOW CHANCES IN THE RIDGES AHEAD OF THE ARCTIC FRONT
PASSAGE PROGGED FOR THIS EVENING/OVERNIGHT. BOTH HI RES AND LONGER
RANGE MODEL SOUNDINGS IN BUFKIT SUGGEST A PERIOD WHERE DEEP
MOISTURE...IN A LAYER FROM ABOUT 600MB TO 850MB...WILL BE WELL
WITHIN THE DENDRITIC GROWTH ZONE. THIS SHOULD SUPPORT EFFICIENT
SNOWFALL FOR A PERIOD...WITH ADDITIONAL SNOW SHOWERS ANTICIPATED
WITH AND BEHIND THE FRONT IN UPSLOPE SNOW UNTIL THE WHOLE BOUNDARY
LAYER FALLS WELL BELOW THE GROWTH ZONE. WITH THIS IN MIND...A
WINTER WEATHER ADVISORY WAS ISSUED FOR THE RIDGES OF PRESTON
TUCKER AND GARRETT COUNTIES THROUGH SATURDAY MORNING.
ELSEWHERE...THE MODEL GUIDANCE HAS CHANGED LITTLE WITH THE TIMING
OF THE SNOW SHOWERS AND POTENTIAL SQUALLS AHEAD OF THE FRONT
PROGGED FOR PASSAGE OVERNIGHT. EXPECT THE LINE TO BE INTO EASTERN
OHIO AND NORTHWESTERN PA BY 00Z AND PITTSBURGH BY 03Z. VARIOUS
RUNS OF THE HRRR AND TO A LESSER DEGREE OTHER SNOW SQUALLS PROGS SUGGEST
THAT THERE WILL BE SOME WEAKENING AS THE LINE COMES ACROSS.
GENERALLY ANTICIPATE A HALF TO AN INCH OF SNOW...WITH SLIGHTLY
HIGHER AMOUNTS NORTH OF PITTSBURGH.
BEHIND THE FRONT...STRONG COLD ADVECTION WILL STEEPEN LAPSE RATES
AND PROVIDE FOR A PERIOD OF GUSTY WINDS AREAWIDE UNTIL LATE
SATURDAY WITH MAXIMUM WIND IN THE BOUNDARY LAYER APPROACHING 25
TO 35KTS. THIS...ADDED TO TEMPERATURES FALLING INTO THE SINGLE
DIGITS WILL LEAD TO WIND CHILL VALUES WELL BELOW ZERO. THIS
SUPPORTS THE WIND CHILL ADVISORY THAT WAS ISSUED. 40MPH WIND
GUSTS OVERNIGHT IN THE RIDGES WILL ALLOW VALUES TO GET VERY CLOSE
TO WARNING CRITERIA BUT AT THIS POINT...THE WATCH HAS BEEN
UPGRADED TO AN ADVISORY WITH SOME -25 VALUES POSSIBLE IN THE
HIGHEST TERRAIN OF TUCKER COUNTY.
IN ADDITION TO THE WIND...LAKE EFFECT SNOW SHOWERS WILL BE
POSSIBLE IN NORTHWEST FLOW WITH MOST IF NOT ALL OF THE MODEL
GUIDANCE SUGGESTING SEVERAL DUAL-LAKE SNOW BANDS. THE LATEST
ITERATION OF MODELS HAS THE MORE PROMINENT BAND SHIFTED SLIGHTLY
SOUTH FROM LAST NIGHT SO WITH UNCERTAINTY IN THE ACTUAL PLACEMENT
OF SNOW BANDS...HAVE OPTED TO UPGRADE THE LAKE EFFECT SNOW WATCH
FOR VENANGO COUNTY TO AN ADVISORY FOR MERCER...VENANGO...AND
FOREST COUNTIES. ADDITIONAL LAKE PLUMES MAY SUPPORT SNOW BEYOND
THESE ADVISORIES THROUGH SATURDAY AFTERNOON...BUT WITH UNCERTAINTY
IN THEIR PLACEMENT...NO ADDITIONAL HEADLINES WERE ADDED.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY/...
LAKE EFFECT SNOW SHOWERS WILL CONTINUE TO TAPER OFF AND SHIFT
NORTHWARD AS A SURFACE RIDGE ATTEMPTS TO BUILD OVERHEAD FOR
SUNDAY. THIS SHOULD ALLOW FOR THE WIND TO BACK OFF...WITH WIND
CHILL CONCERNS DIMINISHING IN OHIO. HOWEVER...WITH THE HIGH
PRESSURE AND LIGHT WIND...TEMPERATURES WILL FALL CLOSE TO OR BELOW
ZERO SATURDAY NIGHT...SO ADVISORIES WILL REMAIN AS IS FOR THE REST
OF THE CWA UNTIL SUNDAY MORNING. TEMPERATURES WILL MODERATE A FEW
DEGREES ON SUNDAY WITH A RETURN OF SOUTHERLY FLOW AND SCATTERING
OF THE CLOUDS. TEMPERATURE FORECAST WAS A BLEND OF GUIDANCE FOR
BOTH PERIODS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
SHORTWAVE MOVING EAST ACROSS THE GREAT LAKES WILL BRING WARM
ADVECTION ALONG WITH AN INCREASE IN DEEPER MOISTURE SUNDAY NIGHT
INTO MONDAY. THIS WILL GIVE A PERIOD OF SNOW ESPECIALLY SOUTH OF
PITTSBURGH WITH SOME ACCUMULATION EXPECTED. TEMPERATURES LOOK TO
RISE LATER SUNDAY NIGHT AND WILL PUSH TO NEAR THE SEASONAL AVERAGE
MONDAY. BY LATER MONDAY THROUGH TUESDAY A STRONG SOUTHERN STREAM
SHORTWAVE WILL INDUCE LOW PRESSURE ALONG THE GULF COAST WHICH WILL
QUICKLY MOVE ACROSS THE MID ATLANTIC STATES. MODELS STILL DIFFER
ON EXACT TRACK BUT SYSTEM WILL CROSS THE SOUTHERN APPALACHIANS AND
INTENSIFY AS IT MOVES TOWARD NEW ENGLAND BY TUESDAY NIGHT.
POTENTIAL FOR SIGNIFICANT SNOW...BUT ALSO POTENTIAL FOR A MIX WITH
RAIN OR ALL RAIN WHERE BETTER QPF IS FORECAST. FOR NOW HAVE NOT
STRAYED FAR FROM PREVIOUS FORECAST ALTHOUGH EVEN THE WARMER ECMWF
WRAPS COLD AIR BACK IN LATER TUESDAY SO HAVE KEPT MAINLY SNOW.
SYSTEM EXITS TUESDAY NIGHT...BUT WILL BE FOLLOWED BY FAST MOVING
CLIPPER SYSTEM WEDNESDAY WHICH WILL DELIVER ANOTHER PERIOD OF SNOW
SHOWERS FOLLOWED BY A QUICK SHOT OF COLD AIR. HEIGHTS ALOFT THEN
BEGIN TO RISE THURSDAY INTO FRIDAY WITH STRONG WARM
ADVECTION...ESPECIALLY ON FRIDAY.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
LIGHT SNOW HAS DROPPED VSBY TO MVFR OR BELOW FOR A TIME AT KMGW AND
KLBE AS A SHORTWAVE SHIFTS EAST TO THE MID ATLANTIC. SNOW SHOWERS
ALSO WILL DEVELOP AHEAD OF APPROACHING ARCTIC FRONT...WITH MVFR TO
IFR THIS EVENING WITH AND BEHIND THE FRONT. WINDS WILL BE GUSTY OVER
25KTS AND TURNING NORTHWEST WITH AND BEHIND THE FRONT.
.OUTLOOK.../FRIDAY NIGHT THROUGH WEDNESDAY/...
SCATTERED RESTRICTIONS IN SNOW SHOWERS SATURDAY. LOW PRESSURE
SYSTEMS WILL BRING WIDESPREAD RESTRICTIONS LATER SUNDAY NIGHT
THROUGH WEDNESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SUNDAY
FOR MDZ001.
WINTER WEATHER ADVISORY UNTIL 10 AM EST SATURDAY FOR MDZ001.
OH...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 11 AM EST
SATURDAY FOR OHZ039-048-049-057>059-068-069.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SUNDAY
FOR OHZ040-041-050.
PA...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SUNDAY
FOR PAZ007>009-013>016-020>023-029-031-073>076.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST SATURDAY FOR
PAZ007>009.
WV...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 11 AM EST
SATURDAY FOR WVZ003-004-012.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SUNDAY
FOR WVZ001-002-021-509>514.
WINTER WEATHER ADVISORY UNTIL 10 AM EST SATURDAY FOR
WVZ512>514.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
145 PM EST FRI FEB 12 2016
.SYNOPSIS...
AN ARCTIC FRONT WILL BRING SNOW SHOWERS TO THE AREA LATER TODAY
THROUGH SATURDAY. MUCH COLDER TEMPERATURES AND DANGEROUS WIND
CHILLS WILL CONTINUE INTO THE WEEKEND BEHIND IT.
&&
.NEAR TERM /THROUGH SATURDAY/...
SHORTWAVE PIVOTING ALONG THE BASE OF THE UPPER TROUGH WILL SUPPORT
INCREASING SNOW CHANCES IN THE RIDGES LATER THIS AFTERNOON AHEAD
OF THE ARCTIC FRONT PASSAGE PROGGED FOR THIS EVENING/OVERNIGHT.
BOTH HI RES AND LONGER RANGE MODEL SOUNDINGS IN BUFKIT SUGGEST A
PERIOD WHERE DEEP MOISTURE...IN A LAYER FROM ABOUT 600MB TO
850MB...WILL BE WELL WITHIN THE DENDRITIC GROWTH ZONE. THIS SHOULD
SUPPORT EFFICIENT SNOWFALL FOR A PERIOD THIS AFTERNOON AHEAD OF
THE ARCTIC FRONT...WITH ADDITIONAL SNOW SHOWERS ANTICIPATED WITH
AND BEHIND THE FRONT IN UPSLOPE SNOW UNTIL THE WHOLE BOUNDARY
LAYER FALLS WELL BELOW VALUES FOR EFFICIENT SNOWFALL. WITH THIS IN
MIND...A WINTER WEATHER ADVISORY WAS ISSUED FOR THE RIDGES OF
PRESTON TUCKER AND GARRETT COUNTIES THROUGH SATURDAY MORNING.
ELSEWHERE...THE MODEL GUIDANCE HAS CHANGED LITTLE WITH THE TIMING
OF THE SNOW SHOWERS AND POTENTIAL SQUALLS AHEAD OF THE FRONT
PROGGED FOR PASSAGE OVERNIGHT. EXPECT THE LINE TO BE INTO EASTERN
OHIO AND NORTHWESTERN PA BY 00Z AND PITTSBURGH BY 03Z. VARIOUS
RUNS OF THE HRRR AND TO A LESSER DEGREE OTHER SNOW SQUALLS PROGSSUGGEST
THAT THERE WILL BE SOME WEAKENING AS THE LINE COMES ACROSS.
GENERALLY ANTICIPATE A HALF TO AN INCH OF SNOW...WITH SLIGHTLY
HIGHER AMOUNTS NORTH OF PITTSBURGH.
BEHIND THE FRONT...STRONG COLD ADVECTION WILL STEEPEN LAPSE RATES
AND PROVIDE FOR A PERIOD OF GUSTY WINDS AREAWIDE UNTIL LATE
SATURDAY WITH MAXIMUM WIND IN THE BOUNDARY LAYER APPROACHING 25
TO 35KTS. THIS...ADDED TO TEMPERATURES FALLING INTO THE SINGLE
DIGITS WILL LEAD TO WIND CHILL VALUES WELL BELOW ZERO. THIS
SUPPORTS THE WIND CHILL ADVISORY THAT WAS ISSUED WITH ADDITIONAL
CONCERN FOR THE RIDGES...AS 40MPH WIND GUSTS MAY SUPPORT AN
UPGRADE OF THE WIND CHILL WATCH THIS AFTERNOON. FURTHER ANALYSIS
WILL BE MADE WITH A DECISION LATER IN THIS SHIFT.
IN ADDITION TO THE WIND...LAKE EFFECT SNOW SHOWERS WILL BE
POSSIBLE IN NORTHWEST FLOW WITH MOST IF NOT ALL OF THE MODEL
GUIDANCE SUGGESTING SEVERAL GUAL-LAKE SNOW BANDS. THE LATEST
ITERATION OF MODELS HAS THE MORE PROMINENT BAND SHIFTED SLIGHTLY
SOUTH FROM LAST NIGHT SO WITH UNCERTAINTY IN THE ACTUAL PLACEMENT
OF SNOW BANDS...HAVE OPTED TO UPGRADE THE LAKE EFFECT SNOW WATCH
FOR VENANGO COUNTY TO AN ADVISORY FOR MERCER...VENANGO...AND
FOREST COUNTIES. ADDITIONAL LAKE PLUMES MAY SUPPORT SNOW BEYOND
THESE ADVISORIES THROUGH SATURDAY AFTERNOON...BUT WITH UNCERTAINTY
IN THEIR PLACEMENT...NO ADDITIONAL HEADLINES WERE ADDED.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
LAKE-EFFECT SNOW SHOWERS ACROSS THE NORTH WILL BE WANING LATE
SATURDAY NIGHT AS THE UPPER-LEVEL LOW MOVES EAST AND A SURFACE HIGH
APPROACHES FROM THE WEST. NORTHWEST FLOW BEHIND THE EXITING FRONT
WILL BRING TEMPERATURES NEAR THE ZERO DEGREE MARK FOR SUNDAY MORNING
LOWS. WITH HIGH PRESSURE STARTING TO BUILD IN...WINDS WILL BE
DECREASING ACROSS EASTERN OHIO. TO THE EAST AND NORTH
HOWEVER...SEVERAL MORE HOURS OF STRONG AND GUSTY WINDS WILL MEAN
WIND CHILL VALUES BELOW -10F. THE HIGHEST ELEVATIONS COULD SEE WIND
CHILLS AT OR BELOW -25F. WITH THIS IN MIND...THE WIND CHILL ADVISORY
WILL CONTINUE FOR MUCH OF THE CWA INTO SUNDAY MORNING...WITH A WIND
CHILL WATCH ACROSS GARRETT AND EASTERN TUCKER COUNTIES.
BRIEF RIDGING SUNDAY AFTERNOON WILL FINALLY DISRUPT THE MEAN
NORTHWEST FLOW PATTERN ALOFT. WARM AIR ADVECTION WILL GRADUALLY KICK
INTO GEAR...BUT WITH SUCH A LOW STARTING POINT...HIGHS WILL STAY
WELL BELOW AVERAGE SUNDAY. THE NEXT WEAK WAVE ARRIVES MONDAY MORNING
SPREADING CLOUDS AND LIGHT SNOW BACK ACROSS THE FORECAST AREA. AN
INCREASE OF CLOUD COVER AND RELATIVELY WARMER AIR SURGING NORTHWARD
WILL KEEP LOWS FROM BOTTOMING OUT MONDAY MORNING.
TAX
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
A DIGGING TROUGH WILL DEEPEN A SURFACE LOW NEAR THE LOWER MISSISSIPPI
VALLEY MONDAY. STRONG SUPPORT FROM THE UPPER-LEVEL JET WILL DEEPEN
THE LOW FURTHER AS IT ADVANCES THROUGH THE SOUTHEASTERN CONUS MONDAY
AFTERNOON. INCREASED SOUTHERLY FLOW WILL TAP INTO GULF AND ATLANTIC
MOISTURE...SPREADING IT NORTHWARD INTO OUR REGION AND EAST. STRONG
ISENTROPIC ASCENT WILL BRING PRECIPITATION THROUGH AT LEAST OUR
EASTERN ZONES BY LATE MONDAY INTO TUESDAY MORNING. STILL QUESTIONS
SURROUNDING THE EXACT TRACK OF THE LOW AND THE RESULTANT WESTWARD
EDGE OF PRECIPITATION...PRECIPITATION TYPE...AND INTENSITY. AS OF THE
00Z RUNS...GUIDANCE IS FAIRLY CONSISTENT ACROSS THE MODEL
SUITE...BUT ALL HAVE NUDGED THE SURFACE LOW WEST OF THEIR POSITION
24HRS AGO.
CURRENT FORECAST CALLS FOR LIKELY SNOW TUESDAY MORNING REACHING WEST
TO THE OHIO RIVER INCLUDING PITTSBURGH. SIGNIFICANT MODEL SPREAD
DOES EXIST FOR HIGH TEMPERATURE VALUES TUESDAY...AND WITH THE
WESTWARD TREND...HAVE BUMPED UP HIGHS A FEW DEGREES. THIS WOULD
FAVOR AT LEAST SOME MIX OF RAIN/SNOW TUESDAY AFTERNOON THAT COULD
ULTIMATELY CUT INTO THE POTENTIAL FOR ACCUMULATING SNOW. BEHIND THIS
SYSTEM...THE BROAD UPPER TROUGH WILL BRIEFLY RE-ESTABLISH OVER THE
NORTHEAST. TEMPERATURES WILL INITIALLY DROP BELOW AVERAGE
THURSDAY...BEFORE REBOUNDING WITH WARM AIR ADVECTION BY THE WEEKEND.
TAX
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL CONTINUE THROUGH THE MORNING BEFORE THE NEXT
SYSTEM BRINGS ANOTHER ROUND OF SNOW AND FLIGHT RESTRICTIONS THIS
AFTERNOON/EVENING. GUSTY NORTHWEST WINDS WILL COMMENCE BY EVENING
AS A COLD FRONT MOVES THROUGH THE AREA WITH A BURST OF SNOW
SHOWERS ALONG IT.
.OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
RESTRICTIONS WILL BE POSSIBLE IN SNOW SHOWERS LATER FRIDAY INTO
SATURDAY. THE NEXT CHANCE FOR WIDESPREAD IFR WILL BE WITH LOW
PRESSURE MONDAY AND TUESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 10 AM EST
SATURDAY FOR MDZ001.
WIND CHILL WATCH FROM MIDNIGHT EST TONIGHT THROUGH SUNDAY
MORNING FOR MDZ001.
OH...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 11 AM EST
SATURDAY FOR OHZ039-048-049-057>059-068-069.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SUNDAY
FOR OHZ040-041-050.
PA...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SUNDAY
FOR PAZ007>009-013>016-020>023-029-031-073>076.
LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 7 PM EST
SATURDAY FOR PAZ007>009.
WV...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 11 AM EST
SATURDAY FOR WVZ003-004-012.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SUNDAY
FOR WVZ001-002-021-509>513.
WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 10 AM EST
SATURDAY FOR WVZ512>514.
WIND CHILL WATCH FROM MIDNIGHT EST TONIGHT THROUGH SUNDAY
MORNING FOR WVZ514.
&&
$$
AREA FORECAST DISCUSSION
NWS BILLINGS MT
930 AM MST FRI FEB 12 2016
.UPDATE...
WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS SHOW A RIDGE AXIS OVER
THE GREAT BASIN AND NORTHERN ROCKIES WITH A 500MB HEIGHT IN EXCESS
OF 570DAM OVER SOUTH CENTRAL MT. COLD UPPER LOW DROPPING INTO THE
NORTH CENTRAL CONUS HAS ALLOWED FOR SOME COLDER LOW LEVEL AIR AND
EAST WINDS TO PUSH INTO OUR CWA SINCE LAST NIGHT...UNDERCUTTING
WHAT IS A RATHER STRONG RIDGE ALOFT. MOIST OVERRUNNING OF THIS
SHALLOW COLDER AIRMASS HAS ALLOWED FOR AREAS OF LIGHT PCPN IN THE
FORM OF RAIN/SNOW TO DEVELOP SINCE LAST NIGHT. LATEST RADAR TRENDS
SUGGEST AN EASTWARD MOVEMENT OF THE PCPN ALREADY...AND LOOKS LIKE
OUR WESTERN FOOTHILLS WILL BE MAINLY DRY FROM THIS POINT ON AS
BAROCLINITY SHIFTS EAST. HAVE LOWERED POPS FOR OUR WEST...
INCLUDING BILLINGS WHICH MAY SEE A LITTLE VERY LIGHT RAIN OR SNOW
THROUGH EARLY AFTERNOON...BUT OTHERWISE THIS IS LOOKING MORE LIKE
A DRY DAY FOR THE BILLINGS METRO AREA. THERE IS STILL POTENTIAL
FOR LIGHT SNOW TO MIX WITH LIGHT FREEZING PCPN OVER OUR EAST
TONIGHT AS A WARM LAYER OVERRUNS THE SHALLOW COLD...WITH BELOW
FREEZING SFC TEMPS LIKELY TO OCCUR ACROSS OUR EAST TONIGHT. WILL
NEED TO MONITOR THIS BUT PCPN SHOULD REMAIN LIGHT AND SOMEWHAT
SPOTTY...REDUCING THE POTENTIAL IMPACTS. TEMPS TODAY WILL HANG IN
THE 30S TO MID 40S ACROSS OUR CENTRAL AND EASTERN PARTS...WITH A
PERSISTENT LIGHT EASTERLY WIND...BUT SHOULD SEE 50S EMERGE ALONG
OUR FOOTHILLS AS DOWNSLOPE WINDS DEVELOP. JKL
&&
.SHORT TERM...VALID FOR TDY AND SAT...
A COUPLE OF SYSTEMS WILL IMPACT THE FORECAST AREA THROUGH THE
SHORT TERM. THE FIRST SYSTEM IS STARTING TO MAKE ITS WAY ACROSS
SOUTHWEST MONTANA AND APPROACHING OUR FAR WESTERN COUNTIES. RADAR
ECHOES ARE INCREASING BUT CLOUD BASES STILL REMAIN FAIRLY HIGH AS
NO PRECIP HAS BEEN REPORTED ACROSS THE LIVINGSTON AND BOZEMAN
AREAS. FURTHER EAST TOWARD THE DAKOTA BORDER...A COLD FRONT BACKED
ITS WAY INTO THAT AREA YESTERDAY AND HAS MADE ITS WAY WESTWARD
PAST BILLINGS EARLY THIS MORNING. SATELLITE IS SHOWING A LOW
STRATUS DECK FROM ABOUT MILES CITY EASTWARD BUT NO PRECIP NOR FOG
HAS BEEN REPORTED. THE HRRR MODEL BRINGS SOME VERY LIGHT SHOWER
ACTIVITY INTO OUR WESTERN AREAS THIS MORNING BUT IT DOESN`T MAKE
IT AS FAR EAST AS BILLINGS. HOWEVER...THE GFS AND ECMWF KEEP
SCATTERED AREAS OF PRECIP ACROSS OUR ENTIRE AREA TODAY WITH THE
BEST CHANCES ACROSS OUR WEST THIS MORNING AND EASTERN ZONES THIS
AFTERNOON AND EVENING. AS A RESULT...WE HAVE REMOVED PRECIP
CHANCES THIS MORNING ACROSS THE EAST AND LOWERED CHANCES JUST A
BIT ELSEWHERE. THERE WILL BE A LARGE CONTRAST WITH TEMPERATURES
TODAY WITH BAKER ONLY SEEING TEMPERATURES AROUND 30 WHILE
LIVINGSTON COULD SEE 50 DEGREES.
FOR SATURDAY...A MUCH STRONGER SYSTEM WITHIN A NORTHWEST FLOW
ALOFT MOVES SOUTHEAST ACROSS OUR AREA DURING THE DAY AND LINGERING
ACROSS OUR FAR EASTERN COUNTIES INTO TONIGHT. WE WILL CONTINUE
WITH A HIGH POP CHANCE ACROSS MOST AREAS THROUGH THE DAY WITH
LIKELY POPS ACROSS CUSTER AND FALLON COUNTIES INTO TONIGHT.
SOUNDINGS FROM MILES CITY TO EKALAKA AND POINTS EAST SHOW THE
POSSIBILITY OF SOME LIGHT FREEZING RAIN AFTER MIDNIGHT TONIGHT SO
AREA ROADS MAY BE SLICK. TEMPERATURES SATURDAY WILL WARM BACK INTO
THE 50S WITH 40S ALONG THE DAKOTA BORDERS. HOOLEY
.LONG TERM...VALID FOR SUN...MON...TUE...WED...THU...
WARM AND ABOVE AVERAGE TEMPERATURES WILL CONTINUE THROUGH NEXT
WEEK AS A RIDGE OF HIGH PRESSURE TO OUR WEST IS STUBBORN TO ERODE.
NOT EXPECTING CONDITIONS TO BE AS WARM AS THIS PAST TUESDAY AND
WEDNESDAY...BUT TEMPERATURES WILL STILL BE IN THE UPPER 50S TO
NEAR 60 IN THE DOWNSLOPING NORTHWEST FLOW.
SEVERAL DISTURBANCES WILL PUSH THROUGH THE AREA DURING THE WEEK.
THE FIRST ONE WILL MOVE THROUGH MONDAY NIGHT THROUGH TUESDAY.
EXPECTING MOSTLY RAIN WITH THIS SYSTEM AS AIR AND GROUND
TEMPERATURES SHOULD STAY ABOVE FREEZING. PRETTY GOOD PRESSURE
RISES BEHIND THIS SYSTEM ALSO BRING ABOUT THE CHANCE FOR SOME
GUSTY CONDITIONS LATE MONDAY THROUGH TUESDAY AFTERNOON. THOUGH
WITH THE BEST PRESSURE RISES APPEARING TO MOVE THROUGH AT NIGHT
WILL NOT ISSUE ANY HIGHLIGHTS AT THIS TIME. IN ADDITION...STRONGEST
MID-LEVEL WINDS LOOK TO STAY MOSTLY WEST OF BILLINGS AND ROUNDUP.
A WEAK WAVE MOVES THROUGH WEDNESDAY BUT LITTLE MOISTURE AND UPPER
LEVEL FORCING SHOULD KEEP SHOWER CHANCES LOW. LAST SYSTEM
APPROACHES FROM THE SOUTHWEST TOWARDS THE LATER PART OF THE WEEK.
BETTER DYNAMICS WITH THIS SYSTEM ARE EXPECTED BUT THE SPLITTING
AND WEAKENING NATURE OF THIS SYSTEM SHOULD JUST ALLOW FOR A SLIGHT
CHANCE OF POPS IN THE PLAINS...WITH MOST OF THE WESTERN TERRAIN
SEEING ANY APPRECIABLE PRECIP. DOBBS
&&
.AVIATION...
MVFR CONDITIONS POSSIBLE TODAY. RAIN/SNOW SHOWERS POSSIBLE THIS
MORNING FROM KLVM TO KMLS...EVENTUALLY SHIFTING TO AREAS EAST OF
KBIL-KSHR FOR THIS EVENING. LIGHT FREEZING RAIN AND PATCHY FOG ARE
POSSIBLE EAST OF KBIL-KSHR TONIGHT. MVFR CONDITIONS THEN POSSIBLE
AT TIMES AGAIN ON SATURDAY ACROSS SOUTHERN MONTANA AND NORTH-
CENTRAL WYOMING. SNOW SHOWERS POSSIBLE SAT MORNING ACROSS SOUTHERN
MT...THEN RAIN SHOWERS POSSIBLE SAT AFTERNOON FOR SOUTHERN MT AND
NORTH-CENTRAL WY. RMS/JKL
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SAT SUN MON TUE WED THU
-------------------------------------------------------
BIL 044 034/052 033/054 038/058 041/059 038/060 037/055
2/O 13/W 23/W 24/W 22/W 11/E 11/E
LVM 057 037/048 034/049 040/055 045/056 041/056 036/052
2/R 04/W 35/W 34/W 32/W 11/N 22/W
HDN 045 029/053 031/054 034/058 037/059 034/060 034/054
3/O 14/W 23/W 24/W 32/W 11/E 11/E
MLS 037 026/050 029/052 033/054 037/054 034/055 033/053
3/S 46/W 21/B 23/W 22/W 11/E 11/E
4BQ 038 028/051 030/050 032/053 037/055 034/059 033/055
3/S 34/W 32/W 24/W 32/W 11/B 11/E
BHK 030 018/043 028/047 028/048 032/049 030/050 029/050
1/E 46/W 31/B 12/W 22/W 11/B 11/E
SHR 046 027/052 027/049 032/054 034/056 032/058 031/054
2/O 13/W 53/W 23/W 22/W 11/B 11/E
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1115 AM CST FRI FEB 12 2016
.SYNOPSIS...
ISSUED AT 320 AM CST FRI FEB 12 2016
ARCTIC HIGH PRESSURE CONTINUES TO BUILD SOUTH FROM THE DAKOTAS AND
MINNESOTA INTO NEBRASKA. AT 08Z...THE LEADING EDGE OF THE FRONT WAS
ANALYZED FROM NEAR PINE RIDGE SOUTH DAKOTA THROUGH NORTH PLATTE THEN
SOUTHEAST ACROSS NCTRL KS. A LARGE AREA OF STRATUS EXTENDS NORTH AND
EAST OF THE FRONT. NO INDICATION YET OF FOG DEVELOPMENT IN WESTERN
NEBRASKA. THE RAP AND HRRR MODELS BOTH SUGGEST DEVELOPMENT NEAR THE
WESTERN EDGE OF THE STRATUS ALONG ADVANCING COLD FRONT IN THE
WESTERN SANDHILLS INTO SOUTHWEST NEBRASKA THIS MORNING. TEMPERATURES
RANGING FROM 26 TO 32 ACROSS WESTERN NEBRASKA...WITH COLDER TEENS
REPORTED IN EASTERN SOUTH DAKOTA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CST FRI FEB 12 2016
THE MAIN FORECAST CONCERNS WILL BE THE BACKDOOR COLD FRONT FORECAST
TO PUSH INTO THE WESTERN NEBRASKA PANHANDLE AND NORTHEAST COLORADO
BY LATE THIS AFTERNOON AND ITS EFFECTS ON HIGH TEMPERATURES ACROSS
WESTERN NEBRASKA TODAY. ONLY MINOR ADJUSTMENTS TO HIGHS TODAY. NEAR
38 IN THE SWRN TIER OF COUNTIES IN CLOSER PROXIMITY TO THE FRONT.
LOWER 20S IN BOYD AND NERN HOLT COUNTY WHERE TEMPERATURES WILL
ACTUALLY HOLD STEADY THROUGH THE DAY FROM THIS MORNINGS LOWS.
FOR TONIGHT...A WARM FRONT WILL BEGIN TO PUSH EAST INTO WESTERN
NEBRASKA. WITH WIDESPREAD STRATUS ALREADY IN PLACE...CONDITIONS WILL
BE FAVORABLE FOR PATCHY FREEZING DRIZZLE TO BEGIN DEVELOPING DUE TO
A LACK OF ICE CRYSTALS INTRODUCED FROM ALOFT. THE PATCHY FREEZING
DRIZZLE FORECAST TO BEGIN LATE THIS EVENING MAINLY WEST OF A LINE
FROM GORDON THROUGH NORTH PLATTE...ADVANCING FURTHER EAST TO NEAR
VALENTINE THROUGH BROKEN BOW BY LATE TONIGHT. WHERE SOME SATURATION
DOES EXIST UP INTO THE DENDRITIC LAYER...A 20 TO 30 PERCENT CHANCE
FOR LIGHT SNOW ACROSS THE EASTERN TWO THIRDS OF THE FORECAST AREA.
THERE WILL BE AN AREA IN BETWEEN WHERE FREEZING DRIZZLE AND LIGHT
SNOW MAY BOTH OCCUR...MAINLY ACROSS WESTERN CHERRY COUNTY SOUTH
THROUGH THE CENTRAL SANDHILLS INTO SOUTHWESTERN NEBRASKA. SINCE ONLY
A SMALL AMOUNT OF FREEZING DRIZZLE CAN IMPACT TRAVEL...WILL CONTINUE
TO HIGHLIGHT THE POTENTIAL FOR THE LIGHT FREEZING DRIZZLE TONIGHT
INTO SATURDAY MORNING IN A SPECIAL WEATHER STATEMENT AND THE
HAZARDOUS WEATHER OUTLOOK.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 320 AM CST FRI FEB 12 2016
12Z SATURDAY AND BEYOND. SATURDAY WILL BE ANOTHER TRANSITION DAY AS
AN ELEVATED WARM FRONT LIFTS EAST ACROSS THE SANDHILLS.
HOWEVER...OUTSIDE OF THE EASTERN PANHANDLE AND WESTERN
SANDHILLS...ALL OTHER LOCATIONS WILL CONTINUE TO SEE TEMPERATURES
BELOW FREEZING. THIS WILL FACILITATE A CONTINUED MENTION
OF FREEZING DRIZZLE INTO THE EARLY AFTERNOON AS SOUNDINGS
INDICATE SATURATION BELOW THE DGZ WHERE THERE/S WEAK OMEGA. WHERE
SUFFICIENT SATURATION IS SHOWN IS ACROSS OUR NORTHEASTERN ZONES
WHERE LIGHT SNOW IS FORECAST. THE MODELS ONLY SUGGEST A FEW
HUNDRETHS AT MOST QPF...AND WITH VERY WEAK LIFT SEEN...SNOW
ACCUMULATIONS SHOULD ONLY AMOUNT TO A FEW TENTHS AT BEST.
ADDITIONAL SNOW CHANCES ARE POSSIBLE ACROSS OUR FAR NORTHERN
ZONES SATURDAY EVENING INTO EARLY SUNDAY AS A FAST MOVING MID-
LEVEL DISTURBANCE DROPS SOUTHEAST ACROSS THE DAKOTAS. THE MODELS
CONTINUE TO INDICATE THE BEST FORCING AND MOISTURE NORTH OF THE
BORDER ACROSS THE DAKOTAS...SO ONLY A FEW TENTHS ADDITIONAL SNOW
ACCUMULATIONS ARE EXPECTED.
WARMING TEMPERATURES ARE FORECAST FOR SUNDAY AS H85 T/S ARE SHOWN TO
CLIMB BACK ABOVE 0C FOR THE ENTIRE CWA. HIGHS IN THE 40S ARE
FORECAST. SUNDAY EVENING...THE MODELS DEPICT A FAST MOVING MID-
LEVEL DISTURBANCE DROPPING SOUTHEAST ACROSS THE HIGH PLAINS
OF COLORADO INTO WESTERN KANSAS. AT THIS POINT...FORCING IS TOO
WEAK WITHIN THE CWA FOR PRECIPITATION...BUT THE 00Z MODELS HAVE
TRENDED SLIGHTLY EAST WITH THE PROJECTED QPF. WILL NEED TO
MONITOR CLOSELY AS AT THIS POINT WE HAVE A DRY FORECAST GOING.
INTO EARLY NEXT WEEK A GRADUAL WARMING TREND IS FORECAST AS
RIDGING BUILDS EAST INTO THE WESTERN ROCKIES AND A TROUGH DEEPENS
INTO THE SOUTHEASTERN STATES. NORTHWEST FLOW ALOFT WILL USHER
ANOTHER DISTURBANCE ACROSS THE REGION LATE MONDAY INTO
TUESDAY...BUT THE MODELS LARGELY DISAGREE IN THE LOCATION OF THE
BEST FORCING...WILL KEEP THE INHERITED DRY FORECAST GOING FOR NOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1115 AM CST FRI FEB 12 2016
AS WIND SWINGS AROUND TO THE SOUTHEAST...THE PROBABILITY OF CEILING
BELOW 1000 FEET WILL INCREASE LATE THIS AFTERNOON AND INTO TONIGHT.
IN ADDITION TO THE LOW CEILINGS...THERE IS A RISK OF FREEZING
DRIZZLE AND LOW LEVEL ICING AFTER 03Z WEST OF AN ANW-BBW LINE. LIGHT
SNOW SHOWERS ARE EXPECTED ALONG AND EAST OF A VTN-LBF LINE.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...ROBERG
SHORT TERM...ROBERG
LONG TERM...JACOBS
AVIATION...SPRINGER
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1208 PM EST FRI FEB 12 2016
.SYNOPSIS...
A FAST MOVING UPPER LEVEL DISTURBANCE WILL BRING A BRIEF CHANCE OF
PRECIPITATION TO MUCH OF THE AREA TODAY. A STRONG DOME OF CANADIAN
HIGH PRESSURE WILL SETTLE IN OVER THE WEEKEND...USHERING IN ANOTHER
PERIOD OF COLD TEMPERATURES. THIS WILL BE FOLLOWED BY ANOTHER
WEATHER SYSTEM WHICH WILL PRODUCE A BETTER CHANCE OF PRECIPITATION
EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
1715 UTC...POPS WERE ADJUSTED BASED ON RADAR TRENDS...FAVORING A
BAND OF SNOW FROM GREENVILLE AND SPARTANBURG TO JUST SOUTH OF
CHARLOTTE. WINDS WERE UPDATED WITH A BLEND OF THE NAM AND ADJMAV...
ALLOWING GUSTS TO INCREASE LATER TODAY AS A SURFACE LOW MOVES OFF THE
COAST AND A TIGHT PRESSURE GRADIENT MOVES IN FROM THE WEST.
1500 UTC UPDATE...POPS HAVE BEEN ADJUSTED TO ACCOUNT FOR LIGHT SNOW
MOVING ACROSS UPSTATE NC. WINDS WERE UPDATED TO INCLUDE THE LATEST
NAM GUIDANCE...WITH GUSTS INCREASING AT HIGHER MC MOUNTAIN ELEVATIONS
LATER TODAY. ONLY MINOR ADJUSTMENTS WERE MADE TO MAXIMUM
TEMPERATURES.
AS OF 650 AM...THE MODELS SEEM TO BE LATCHING ONTO MORE MOISTURE OR
BETTER LLVL LIFT EAST OF THE MTNS. THE 6Z GFS AND THE LATEST RAP AND
HRRR NOW HAVE HIGHER POP/MORE COVERAGE OF SNOW SHOWERS ACROSS THE
PIEDMONT. IT LOOKS LIKE A BAND MAY SET UP SOMEWHERE ACROSS THE
UPSTATE. HOWEVER...CONFIDENCE IS STILL LOW. POPS MAY NEED TO BE
ADJUSTED UPWARD IF TRENDS ON RADAR LOOK TO BE LINING UP WITH THE
HRRR. OTHERWISE...FCST LOOKS ON TRACK.
AS OF 315 AM...A VIGOROUS SHORT WAVE CAN BE SEEN ON WATER VAPOR
IMAGERY DIVING INTO THE OHIO VALLEY TOWARD THE BASE OF A LONG WAVE
TROF ALONG THE EAST COAST. THIS WAVE WILL CROSS THE CWFA JUST AFTER
DAYBREAK...AND WILL BE ACCOMPANIED BY A 130 KT 300 MB JET. THIS WILL
RESULT IN STRONG MID AND UPPER LEVEL FORCING FROM ABOUT 12Z TO 18Z
TODAY. AT THE SFC...A WEAK ALBERTA CLIPPER WAS ANALYZED OVER
MO...AND WILL STREAK JUST SOUTH OF THE CWFA DURING THE DAY. LLVL FLOW
IS BACKING OUT OF THE WSW...BUT STRUGGLING TO TAP INTO MUCH MOISTURE.
SO THE FORECAST CHALLENGE FOR TODAY WILL BE HOW MUCH QPF WILL
ACCOMPANY THE SYSTEM...AS THE OP MODELS SHOW SOME SPREAD ON COVERAGE
AND AMOUNTS. THE 00Z NAM KEEPS THE PIEDMONT DRY...WHILE THE
OTHER OP MODELS HAVE SOME LIGHT AMOUNTS. I LIKE THE AGREEMENT OF THE
CAMS ON THE SIMULATED REFLECTIVITY...SHOWING LIGHT PRECIP BREAKING
OUT ACRS THE MTNS RIGHT AROUND DAYBREAK...THEN QUICKLY SPREADING
EAST ACROSS THE PIEDMONT DURING THE LATE MORNING HOURS. BY EARLY
AFTN...THE MODELS SHOW PRECIP CONFINED TO WESTERLY UPSLOPE AREAS
ALONG THE TN BORDER. I THINK MUCH OF WHAT THE CAMS ARE SHOWING WOULD
BE VIRGA...GIVEN THE MOISTURE MAINLY IN THE MID LEVELS. SO POPS SHOW
LIKELY IN THE MTNS...ESP NEAR THE TN BORDER...WHILE ONLY SLIGHT
CHANCE TO LOW-END CHANCE EAST. FCST PROFILES SHOW THAT THIS WOULD BE
A RAIN/SNOW EVENT...WITH WET-BULB EFFECTS ALLOWING FOR LIGHT SNOW
SHOWERS AND/OR FLURRIES JUST ABOUT ANYWHERE THIS MORNING. ACCUMS
THRU THE DAY WILL BE IN THE MTNS...WITH NOTHING MORE THAN A DUSTING
EXPECTED ELSEWHERE. TEMPS SHOULD BE ABOUT 10-15 DEGREES BELOW NORMAL
UNDER MOSTLY CLOUDY SKIES AND SPOTTY PRECIP.
TONIGHT...THE CLIPPER SYSTEM WILL ALREADY BE DEVELOPING A NEW LOW
OUT OVER THE ATLANTIC JUST EAST OF THE OUTER BANKS BY EARLY
EVENING...WHILE A STRONG ARCTIC HIGH (PRESSURE AROUND 1044 MB)
BUILDS IN ACROSS THE PLAINS TO THE SOUTHEAST STATES. THE SFC
PRESSURE GRADIENT NEVER GETS THAT IMPRESSIVE ATOP THE CWFA.
HOWEVER...THE 850 MB FLOW RAMPS UP OUT OF THE NW TO 40-55 KT ACROSS
THE NC MTNS WITH VERY STRONG CAA. THIS WILL RESULT IN A DOWN RIGHT
COLD AND BLUSTERY NIGHT IN THE MTNS...WITH THE ADDITION OF LINGERING
MOISTURE FOR NW FLOW SNOW SHOWERS. IN FACT...THE COLD AIR AND NEAR
PERFECT ORTHOGOTHAL DIRECTION COULD MAKE FOR EFFICIENT SNOW
PRODUCING SHOWERS ALONG THE TN LINE. THE EXPECTED SNOW WITH THE
CLIPPER ALONG WITH THE NW FLOW SNOW SHOULD RESULT IN TOTAL ACCUMS OF
2-4" ACROSS THE USUAL NW FLOW UPSLOPE AREAS. THIS ALONG WITH WINDS
IN THE 25-40 MPH RANGE AND GUSTS IN THE 40-55 MPH RANGE SEEMS TO
WARRANT A WINTER WEATHER ADVISORY. I WILL START IT AT NOON TO
EMCOMPASS THE SNOW ACCUMS EXPECTED TODAY...AND GO THRU 6 AM SATURDAY
(WHEN SNOW SHOWER ACTIVITY WILL TAPER OFF). IN ADDITION...TEMPS WILL
BE PLUMMETING INTO THE TEENS TO SINGLE DIGITS...SO WIND CHILLS WILL
BE IN THE -5 TO -15 F RANGE FOR MOST LOCATIONS ABOVE 3500 FT. A WIND
CHILL ADVISORY WILL BE ISSUED STARTING AT MIDNIGHT...ALTHOUGH SOME
LOCATIONS ABOVE 5000 FT OR SO MAY START SEEING DANGEROUS WIND CHILLS
EARLIER IN THE EVENING. THE REST OF THE CWFA SHOULD SEE CLEARING
SKIES AND LINGERING WINDS WITH CHILLY TEMPS ABOUT 8-15 DEGREES BELOW
NORMAL.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
AS OF 300 AM EST FRIDAY...A BROAD TROUGH OF LOW PRESSURE WILL EXTEND
SOUTHWARD ACROSS THE EASTERN UNITED STATES SATURDAY FROM A LOW
CENTER OVER SOUTHERN QUEBEC. ISOLATED TO SCATTERED NW FLOW SNOW
SHOWERS COULD LINGER ACROSS THE NORTHERN MOUNTAINS EARLY
SATURDAY...BUT WITH MOISTURE DIMINISHING THROUGH THE DAY. COLD
MORNING TEMPERATURES AND BRISK NW FLOW WILL PERMIT BITTER WIND
CHILLS TO CONTINUE THROUGH SATURDAY MORNING ACROSS THE
MOUNTAINS...AND ON INTO SATURDAY NIGHT/SUNDAY MORNING ACROSS THE
NORTHERN MOUNTAINS. MEANWHILE...VERY COLD AIR WILL DIVE SOUTHEAST
FROM CANADA INTO THE REGION ON THE BACK SIDE OF THE TROUGH AS THE
ASSOCIATED ARCTIC HIGH PRESSURE MOVES ACROSS THE MIDWEST ON SATURDAY
AND REACHES THE EASTERN SEABOARD BY LATE SUNDAY. IN THE COLD
AIRMASS...MAX TEMPERATURES WILL RUN AT LEAST 20 DEGREES BELOW CLIMO
IN MOST AREAS...WHILE SUNDAY MORNING MINS WILL BE 10 TO 20 DEGREES
BELOW CLIMO. A WIND CHILL ADVISORY WILL CONTINUE UNTIL MID SUNDAY
MORNING ACROSS THE NORTHERN NC MOUNTAINS.
THE UPPER FLOW WILL FLATTEN SLIGHTLY OVER THE EAST ON SUNDAY AS A
NORTHERN STREAM SHORTWAVE DIGS INTO THE MIDWEST WHILE A SOUTHERN
STREAM SYSTEM TAKES SHAPE FROM THE FOUR CORNERS REGION TOWARD TX.
THE FIRST HINT OF MID LEVEL UPGLIDE MOISTURE WILL ARRIVE IN THE CWA
FROM THE WEST ON SUNDAY...BUT WITH DRY LOW LEVELS PRECLUDING ANY
PRECIPITATION FROM REACHING THE GROUND THROUGH LATE DAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 300 AM EST FRIDAY...A WINTRY MIXED MAG OF PRECIPITATION IS
LOOKING LIKELY STARTING SUNDAY NIGHT INTO MONDAY GIVEN THE VERY COLD
AND DRY AIRMASS THAT WILL BE PRESENT OVER THE AREA BEFORE ONSET.
THERE IS GOOD MODEL CONSENSUS ON THE ENERGY WITH THE SOUTHERN STREAM
SYSTEM SHARPENING UP RAPIDLY OVER THE LOWER MS RIVER VALLEY SUNDAY
NIGHT INTO MONDAY. MEANWHILE...THE SURFACE HIGH CENTER TO THE NORTH
WILL RETREAT OFFSHORE. LOW LEVEL UPGLIDE MOISTURE WILL FILL IN
RAPIDLY ACROSS OUR AREA EARLY MONDAY...WITH THE 850 MB ZERO ISOTHERM
ALONG THE SOUTHERN FRINGE OF THE AREA AROUND DAYBREAK MOVING RAPIDLY
TOWARD THE NORTHERN FRINGE OF THE FORECAST AREA BY MID AFTERNOON.
EVEN THOUGH COLD AIR DAMMING IS VERY LIKELY...THE COLD AIR MAY ONLY
STAY DEEPLY ENTRENCHED EAST OF THE NORTHERN BLUE RIDGE GIVEN THE
INCREASINGLY OFFSHORE PARENT HIGH LOCATION. STILL...PROFILES ARE
PLENTY COLD FOR PRECIPITATION TO START AS SNOW THROUGHOUT BEFORE
DAYBREAK MONDAY...WITH A BLOSSOMING WARM NOSE THEN INVADING THE
SOUTHERN TIER OF THE FORECAST AREA MONDAY MORNING AND MOVING
NORTHWARD ACROSS THE REGION THROUGH THE DAY.
THE BEST UPPER FORCING ACTUALLY ARRIVES MONDAY NIGHT AS UPPER JET
DIVERGENCE BRIEFLY SETS UP AND DEEP LAYER Q VECTOR FORCING CROSSES
THE REGION AHEAD OF THE INCREASINGLY NEGATIVE TILT UPPER TROUGH.
FORCING AND MOISTURE WILL BE STRONGLY FOCUSED ON THE REGION LATE
MONDAY NIGHT/EARLY TUESDAY WITH THE SURFACE LOW CENTER LIKELY
TRACKING THROUGH THE CENTRAL CAROLINAS...THE CAD GETTING FURTHER
PINCHED OFF TO THE NORTH...AND THE HEAVIEST PRECIPITATION DURING THE
WARMEST PART OF THE EPISODE.
SO...THERE ARE PLENTY OF POTENTIAL HAZARDS. SIGNIFICANT ICE AND SNOW
ACCUMULATIONS WILL BE POSSIBLE...MAINLY OVER WESTERN NC AND
ESPECIALLY ALONG AND NORTH OF INTERSTATE 40. IN ADDITION...HEAVY QPF
COULD CREATE SOME HYDRO ISSUES MONDAY NIGHT INTO TUESDAY MORNING
WITH THE FRONTOGENESIS MAX WEST OF THE PASSING 850 MB LOW LIKELY
LINGERING OVER THE EASTERN SLOPES OF THE MOUNTAIN. THE HEAVY
RAINFALL ON TOP OF ACCUMULATED SNOW AND ICE COULD CREATE SOME LOCAL
ICE DAMMING PROBLEMS ON SHALLOW SLOPED ROOFS. FINALLY...SURFACE
BASED CAPE VALUES OF 200 TO 300 J/KG ARE POSSIBLE TOWARD DAYBREAK
TUESDAY IN THE LOWER PIEDMONT...WITH 850 TO 500 MB LAPSE RATES OF
6.5 TO 7.0 DEG C/KM...ALONG WITH BACKED 50 KT 850 MB FLOW. THIS
COULD CREATE A BRIEF SEVERE THUNDERSTORM THREAT FROM CHESTER TO
MONROE OR THEREABOUTS AROUND DAYBREAK TUESDAY. OTHERWISE...DRYING
WILL DEVELOP FROM THE SOUTHWEST THROUGH TUESDAY AFTERNOON...WITH
NORTHERN MOUNTAIN UPSLOPE MOISTURE BRIEFLY DRYING UP.
A REINFORCING CLIPPER MAY DIVE INTO THE MEAN EASTERN TROUGH TUESDAY
NIGHT...WITH THE GFS MORE AMPLIFIED THAN THE ECMWF...PRODUCING
MAINLY ADDITIONAL UPSLOPE SNOW SHOWER COVERAGE OVER THE WESTERN
MOUNTAINS. HEIGHTS WILL BUILD EASTWARD FROM THE BROAD WESTERN RIDGE
WEDNESDAY THROUGH THURSDAY...WITH ASSOCIATED WARMING AND DRYING.
&&
.AVIATION /17Z FRIDAY THROUGH TUESDAY/...
AT KCLT...SNOWFALL REMAINS POSSIBLE VERY EARLY IN THE FORECAST...
WITH RESULTING VSBY AND CIG RESTRICTIONS. IMPROVEMENT IS EXPECTED
THIS AFTERNOON...AS SNOW MOVES OFF TO THE EAST. NE WINDS ARE EXPECTED
TO SHIFT TO SW THIS AFTERNOON...THEN VEER NW THIS EVENING BEHIND A
DEPARTING LOW PRESSURE SYSTEM. WIND GUST POTENTIAL WILL INCREASE
OVERNIGHT AND EARLY TUESDAY.
AT KAVL...SNOW SHOWERS WITH CIG AND VSBY RESTRICTIONS MAY LINGER IN
THE VICINITY THIS AFTERNOON AND EVENING...BACKING OFF TOWARD THE TN
BORDER TOWARD DAWN. NW WINDS WILL INCREASE AS A LOW PRESSURE SYSTEM
DEPARTS AND THE PRESSURE GRADIENT TIGHTENS AHEAD OF HIGH PRESSURE.
ELSEWHERE...SNOW SHOWERS WILL MOVE OFF TO THE EAST...WITH CIGS AND
VSBY IMPROVING. WINDS WILL FAVOR THE W THIS AFTERNOON AND
EVENING...VEERING NW OVERNIGHT...WITH GUST POTENTIAL GRADUALLY
INCREASING.
OUTLOOK...AN ARCTIC AIR MASS WILL BUILD OVER THE REGION THIS
WEEKEND...WITH UPSLOPE CLOUDS ON THE WEST SIDE OF THE APPALACHIANS.
A SIGNIFICANT WINTER WEATHER SYSTEM IS POSSIBLE EARLY NEXT WEEK.
CONFIDENCE TABLE...
17-23Z 23-05Z 05-11Z 11-12Z
KCLT MED 71% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 93% HIGH 100% HIGH 100% HIGH 100%
KAND LOW 57% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULE TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLET HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK:
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...WINTER WEATHER ADVISORY UNTIL 6 AM EST SATURDAY FOR NCZ033-
048>052.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM EST SUNDAY
FOR NCZ033-049-050.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST SATURDAY
FOR NCZ048-051-052-058-059.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...ARK/JAT
SHORT TERM...HG
LONG TERM...HG
AVIATION...JAT
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1201 PM EST FRI FEB 12 2016
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL PASS JUST SOUTH OF THE REGION THIS
AFTERNOON BRINGING PERIODS OF LIGHT SNOW OR SNOW SHOWERS
ESPECIALLY ACROSS THE MOUNTAINS. A SURGE OF ARCTIC AIR FOLLOWS
THIS SYSTEM OVERNIGHT RESULTING IN VERY WINDY CONDITIONS AND
BITTERLY COLD TEMPERATURES...ALONG WITH SOME ADDED SNOW SHOWERS
FOR THE FAR WESTERN SLOPES OF THE APPALACHIANS INTO SATURDAY. BY
MONDAY ANOTHER WINTER STORM SYSTEM WILL BEGIN TO AFFECT THE REGION
WITH THE POTENTIAL FOR SNOW AND MIXED PRECIPITATION THROUGH THE
FIRST PART OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM EST FRIDAY...
COLUMN CONTINUING TO SLOWLY MOISTEN AS AXIS OF ISENTROPIC LIFT
SPILLS EAST AHEAD OF THE STRONG UPPER SHORTWAVE SEEN ON WATER
VAPOR PASSING TO THE SOUTH. LATEST SHORT TERM GUIDANCE CONTINUES
TO VARY ON JUST HOW FAR EAST ANY OF THESE BANDS WILL MAKE IT WITH
SOME PRIMARILY CONFINED TO THE WESTERN SLOPES...WHILE OTHERS
INCLUDING THE WRF-ARW AND TO SOME DEGREE THE HRRR SPILL LIGHT
SNOW EAST TO THE BLUE RIDGE AND POINTS EAST. ALTHOUGH THIS LOOKS
OVERDONE...PERIOD OF BACKING ALOFT MAY BE ENOUGH TO HELP PUSH
LIGHT SNOW FARTHER EAST THAN TYPICAL DOWNSLOPING WOULD ALLOW
ESPCLY WITH THE UPSTREAM TRAILING CHANNELED VORT AXIS SEEN BACK
IN KY. THUS BUMPED UP AMOUNTS A BIT ACROSS THE FAR SW PER CURRENT
TRAJECTORY OF SNOW TO THE WEST AND HEADING OUT EAST OF THE BLUE
RIDGE FOR AT LEAST A COATING. APPEARS LEAST AMOUNT OF SNOW MAY
OCCUR OVER THE NORTH AS THE TRANSFER OF ENERGY FROM THE MOUNTAINS
TO THE COASTAL DUCKS FARTHER SOUTH THROUGH THE AFTERNOON. STILL
GOING HEADLINES ON TRACK FOR AN INCH OR SO TODAY OUT WEST AND
COMBINED UPSLOPE OVERNIGHT SO NO CHANGES THERE OTHER THAN TO TWEAK
AMOUNTS. ALSO MADE SOME SLIGHT UPWARD ADJUSTS TO TEMPS MAINLY EAST
WHERE COULD SURGE UP AS A FEW BREAKS DEVELOP AHEAD OF ANY PRECIP
THAT ATTEMPTS TO HEAD EAST OF THE RIDGES. THINK MOST PTYPE EVEN
OUT THERE TO BE SNOW GIVEN COLDNESS ALOFT SO RUNNING WITH MOSTLY
SNOW/SNOW SHOWERS.
WILL NEED TO TAKE A LOOK AT THE WINDS OVERNIGHT INTO SATURDAY
MORNING BEHIND THE PASSING ARCTIC FRONT AS COULD SEE WARNING
CRITERIA SW BUT WILL AWAIT 12Z GUIDANCE BEFORE UPDATING.
PREVIOUS DISCUSSION AS OF 400 AM EST FRIDAY...
THE MAIN WEATHER PLAYERS FOR OUR REGION TODAY AND TONIGHT WILL BE AN
UPPER LEVEL SHORT WAVE BRINGING SOME LIGHT SNOW TO THE FAR WESTERN
PORTION OF THE AREA BEFORE A STRONG COLD FRONT MOVES THROUGH AND SETS
OFF ANOTHER ROUND OF UPSLOPE SNOW SHOWERS WEST OF THE BLUE RIDGE.
BELIEVE THE MOUNTAIN EMPIRE REGION WILL SEE AN INCH OR LESS OF SNOW
BEFORE THE UPSLOPE REALLY KICKS IN AND PROVIDES ADDITIONAL ACCUMULATIONS
ALONG THE FAR WESTERN SLOPES THROUGH TONIGHT. THE AIR MOVING IN BEHIND
THE FRONT IS QUITE COLD INDEED AND WILL CREATE SOME VERY STEEP LOW LEVEL
LAPSE RATES AND EVEN A BIT OF CAPE...WHICH MAY BRING US ANOTHER CHANCE
FOR A PERIOD OF THUNDERSNOW EARLY TONIGHT. MESO MODELS ALSO INDICATE
A DECENT UPSTREAM CONTRIBUTION TO THE MOISTURE FROM THE GREAT LAKES.
BELIEVE THESE FACTORS WILL COMBINE TO GENERATE SNOW ACCUMULATIONS
GENERALLY IN THE 2 TO 4 INCH RANGE FOR THE WESTERN SLOPES WITH SOME
LOCALLY HIGHER AMOUNTS POSSIBLE SO WILL ISSUE AN ADVISORY FOR THIS AREA
FROM THIS AFTERNOON THROUGH TONIGHT.
LOW LEVEL WINDS WILL ALSO START TO INCREASE TONIGHT AND GOOD MOMENTUM
TRANSFER IN THE BOUNDARY LAYER WILL ALLOW FOR QUITE A BIT OF WIND
OVERNIGHT WITH GUSTS OVER 40 MPH EXPECTED ESPECIALLY OVER THE HIGHER
TERRAIN. THIS WILL COMBINE WITH TEMPERATURES WEST OF THE BLUE RIDGE
FALLING INTO THE SINGLE DIGITS TO GENERATE WIND CHILL VALUES OF 5 TO 15
BELOW ZERO...WITH READINGS TO 25 BELOW FOR WESTERN GREENBRIER COUNTY IN
WEST VIRGINIA. WINDS WILL GRADUALLY SUBSIDE ON SATURDAY BUT THE
COMBINATION OF WIND AND VERY COLD TEMPERATURES WILL CONTINUE TO
GENERATE VERY LOW WIND CHILL VALUES THROUGH SUNDAY MORNING. A WIND
CHILL ADVISORY WILL BE ISSUED FOR THE AREA ALONG AND WEST OF THE BLUE
RIDGE FROM TONIGHT THROUGH SUNDAY MORNING WITH A WIND CHILL WARNING FOR
WESTERN GREENBRIER. CONDITIONS EAST OF THE RIDGE WILL NOT BE QUITE AS
SEVERE AS LOWS TONIGHT REACH THE 15 TO 20 DEGREE RANGE WITH WIND CHILL
VALUES INTO THE SINGLE DIGITS.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
AS OF 430 AM EST FRIDAY...
COLDEST AIR OF THE SEASON STILL SLATED TO BE SPREADING INTO THE
REGION FOR SATURDAY...WITH TEMPERATURES BOTTOMING OUT SUNDAY
MORNING. THE MODELS HAVE BACKED OFF THE INTENSITY OF THE COLD AIR
MASS JUST SLIGHTLY WITH EACH SUCCEEDING RUN...NOW STOPPING AROUND
-22C ACROSS THE FAR NORTHERN PORTION OF THE CWA. SIMILAR EVENTS
THE PAST TWO YEARS HAVE SEEN READINGS CLOSER TO -25/-26C...SO FEEL
CONFIDENT THAT MORNING LOW TEMPERATURES SUNDAY MORNING WILL FALL A
COUPLE OF DEGREES SHY OF WHAT WE SAW THE LAST COUPLE OF YEARS WITH
SIMILAR ARCTIC OUTBREAKS. ALSO...SNOW COVER IS LIMITED EAST OF
THE ALLEGHANY FRONT AND THE MOUNTAINS OF SW VA/NW NC...SO THAT
WILL ALSO NOT HELP DRIVE TEMPERATURES TO THE LEVELS WE SAW AROUND
THIS TIME LAST YEAR. NONETHELESS...IT WILL BE BITTERLY COLD AND
VERY WINDY...PROMPTING A CONTINUATION OF THE WIND CHILL ADVISORIES
WEST OF THE BLUE RIDGE AND THE WARNING FOR WESTERN GREENBRIER.
WINDS WILL BEGIN TO DIMINISH LATE IN THE DAY AND SATURDAY
NIGHT...BUT WITH TEMPERATURES FALLING INTO THE SINGLE DIGITS AND
NEAR 0 TO -5F AT THE HIGHER ELEVATIONS...THE ADVISORIES/WARNINGS
ARE WARRANTED TO CONTINUE INTO SUNDAY MORNING AS IT WILL TAKE VERY
LITTLE FOR WIND CHILLS TO MEET CRITERIA WITH TEMPS THAT LOW.
UPSLOPE SNOW SHOWERS SHOULD BE WINDING DOWN SATURDAY MORNING
FAIRLY QUICKLY AS THE VERY DRY ARCTIC AIR MASS SPREADS INTO THE
REGION. WILL KEEP SLIGHT CHANCE TO LOW CHANCE POPS FOR SNOW
SHOWERS GOING THROUGH MID-DAY...THEN END THEM...ALBEIT SOME
FLURRIES COULD CONTINUE INTO THE AFTERNOON AS ARCTIC COLD-
ADVECTION SQUEAKS OUT ANY REMAINING MOISTURE. WINDS WILL BE
STRONG AND GUSTY THROUGHOUT THE DAY...BUT LIKELY DROP BELOW
ADVISORY CRITERIA IN THE WEST DURING THE AFTERNOON...ALTHOUGH THAT
IS LUMPED INTO THE WSW.
THE ARCTIC HIGH SETTLES OVER THE REGION SUNDAY MORNING WITH...AS
NOTED ABOVE...BITTERLY COLD TEMPERATURES...BUT WINDS TRENDING
TOWARD CALM. BY AFTERNOON...THE ARCTIC HIGH HAS ALREADY SHIFTED
TOWARD THE VA/MD COAST WITH RETURN FLOW EVIDENT ESPECIALLY IN
SOUTHWEST VA. A NORTHERN STREAM SHORT WAVE QUICKLY MOVES TOWARD
THE REGION BY SUNDAY AFTERNOON...WITH INCREASING MOISTURE FROM TOP
DOWN. THE ANTECEDENT AIR MASS WILL CLEARLY BE VERY DRY AND COLD
AND NOT SURE HOW QUICKLY THE AIR MASS WILL SATURATE TO ALLOW
GENERATED PRECIPITATION ALOFT TO REACH THE GROUND. INDICATIONS ARE
THAT THIS SHOULD BEGIN TO TAKE PLACE AFTER SUNSET IN THE WEST AND
CLOSER TO MIDNIGHT IN THE EAST. THUS...WILL LEAVE THE DAYTIME
HOURS OF SUNDAY DRY WITH POPS BELOW 15 PERCENT. ALL PRECIPITATION
SUNDAY NIGHT WILL BE SNOW ACROSS THE ENTIRE CWA AS THE SOUNDINGS
REMAIN BELOW FREEZING AT ALL LEVELS.
AS WE MOVE INTO MONDAY...THE SITUATION BECOMES INCREASINGLY
COMPLICATED. THE NORTHERN STREAM SHORT WAVE WILL MOVE NORTHEAST OF
THE REGION EARLY MONDAY...WHILE A STRONGER SOUTHERN STREAM SHORT
WAVE DEEPENS INTO THE MID-SOUTH. DEEP SURFACE LOW PRESSURE WILL
THEN DEVELOP IN RESPONSE TO THIS SECOND SOUTHERN STREAM SHORT WAVE
ACROSS THE MID-SOUTH...MOVING TOWARD THE EASTERN TN VALLEY BY
MONDAY EVENING. ALL OF THE MODELS HAVE TAKEN A SLIGHT WEST JOG
WITH THE SURFACE LOW PRESSURE...RESULTING IN THE POTENTIAL FOR
WARMER AIR FROM THE SOUTH AND SOUTHEAST TO ENCROACH ON THE REGION.
NONETHELESS...THE ANTECEDENT AIR MASS WILL BE VERY COLD AND MODELS
OFTEN ADVERTISE A WARMUP TOO QUICKLY WITH THIS TYPE OF SITUATION.
A WARM FRONT WILL LIE ACROSS THE REGION MONDAY NIGHT...THEN BEGIN
TO LIFT NORTHWARD EARLY TUE. THIS IS WHEN THE P-TYPE ISSUES WILL
BEGIN WITH A TRANSITION FROM SNOW TO SLEET TO FREEZING RAIN AND
PERHAPS EVEN RAIN IN PARTS OF THE PIEDMONT. THIS ENTIRE PERIOD
WILL EVENTUALLY HAVE TO BE HANDLED BY TOP-DOWN OR SIMILAR P-TYPE
PROCEDURES...BUT GIVEN IT IS STILL OUT IN THE DAY 4 AND BEYOND
PERIOD....WILL STICK WITH A RAIN/SNOW MIXTURE FOR NOW. ALTHOUGH
SNOW/SLEET/ICE AMOUNTS STILL HIGHLY IN QUESTION...IT STILL APPEARS
QUITE CERTAIN THAT WINTER STORM CRITERIA WILL LIKELY BE MET ACROSS
MUCH OF THE CWA IN THE SUN NIGHT THROUGH EARLY TUE TIME
FRAME...WITH STILL THE POTENTIAL FOR SIGNIFICANT SNOWFALL
ACCUMULATIONS IN THE WESTERN MOUNTAINS. THUS...WILL CONTINUE TO
HIGHLIGHT THIS POTENTIAL IN THE HWO. A WINTER STORM WATCH FOR THIS
PERIOD WILL LIKELY NEED TO FOLLOW ON THE HEELS OF THE CURRENT
WINTER WEATHER ADVISORIES.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 100 PM EST THURSDAY...
A DEEPENING SURFACE LOW...REMAINING MOSTLY INLAND...WILL TRACK
ACROSS THE CWA TUE...MOVING TOWARD THE NORTHERN MID-ATLANTIC BY
EVENING. SIGNIFICANT WINTER WEATHER WILL LIKELY CONTINUE FOR MUCH
OF THE CWA...BUT POTENTIALLY TRANSITIONING TO RAIN ACROSS THE
PIEDMONT. BUFKIT SHOWS CONSIDERABLE VERTICAL MOTION IN THE SNOW
GROWTH ZONE EARLY TUESDAY...SO THERE COULD BE A BURST OF HEAVY
SNOW/SLEET BEFORE THE DRY SLOT SPREADS INTO THE REGION FROM THE
SOUTHWEST AND SHUTS OFF THE HEAVIER PRECIPITATION...WHICH SHOULD
OCCUR BY MIDDAY TUE. BY EVENING...COLDER AIR BEGINS TO FILTER
BACK INTO THE WESTERN AREAS AND UPSLOPE SNOW SHOWERS COMMENCE ONCE
AGAIN.
IN THE WAKE OF THE STRONG SYNOPTIC SYSTEM TUESDAY...ANOTHER
CLIPPER IS EVIDENT IN CONTINUED NORTHWEST FLOW ALOFT. OVERALL
WARMING OF ANY SIGNIFICANCE LOOKS LIMITED DURING THIS PERIOD.
ALTHOUGH PREVIOUS RUNS OF THE GFS SHOWED SUBSTANTIAL WARMING
DURING THIS TIME FRAME...THAT IS NOT EVIDENT TODAY. MEXMOS KEEPS
WESTERN AREAS MOSTLY AT OR BELOW FREEZING THROUGH MIDWEEK...WITH
ONLY LIMITED WARMING DURING THE LATER HALF OF THE WEEK. THE
CLIPPER TUE NIGHT/WED...COULD BRING ADDITIONAL MINOR SNOW
ACCUMULATIONS TO THE WESTERN PARTS OF THE CWA BEFORE MOVING
NORTHEAST OF THE REGION. OUTSIDE OF UPSLOPE SNOW SHOWERS...THAT
SHOULD BE THE LAST OF ANY SYNOPTIC-SCALE INDUCED PRECIPITATION FOR
THIS PERIOD.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1150 AM EST FRIDAY...
LOWER CIGS AND ASSOCIATED LIGHT SNOW BANDS WILL CONTINUE TO HEAD
EAST CROSSING THE BLUE RIDGE BY EARLY AFTERNOON. THIS WILL RESULT
IN PERIODS OF MVFR/IFR OVER THE WESTERN SITES AND BRIEF MVFR
ESPCLY AROUND KDAN BY MID AFTERNOON. ONCE THE WINDS TURN MORE
NORTHWEST SHOULD SEE CONDITIONS IMPROVE OVER THE EAST AND RETURN
TO VFR BY EARLY EVENING IF NOT SOONER.
HOWEVER FOR KBCB/KBLF/KLWB THE NWLY WINDS WILL BE UPSLOPE AND
THIS WILL KEEP SNOW SHOWERS AT THESE LOCATIONS WITH MVFR/IFR
CIGS/VSBYS INTO THIS EVENING AT KBCB...CONTINUING OVERNIGHT AT
KBLF/KLWB. BEHIND THE FRONT ALL SITES WILL SEE SIGNIFICANT WIND
GUSTS AS A WELL MIXED BOUNDARY LAYER ALLOWS FOR EFFICIENT MOMENTUM
TRANSFER OF INCREASING LOW LEVEL FLOW. EXPECT G40-45KT AT KROA
WITH GUSTS AOA 35KT FOR KBCB/KBLF OVERNIGHT.
A GRADUAL RETURN TO VFR APPEARS LIKELY ON SATURDAY ALTHOUGH
KBLF/KLWB LIKELY TO KEEP MVFR IN SNOW SHOWERS AROUND UNTIL LATE IN
THE DAY. WINDS WILL REMAIN STRONG ON SATURDAY WITH GUSTS TO 30-40
KTS LIKELY UNTIL HIGH PRESSURE BUILDS IN DURING THE AFTERNOON.
EXTENDED DISCUSSION...
THE NEXT LOW PRESSURE SYSTEM WILL ARRIVE ON SUNDAY NIGHT.
CONFIDENCE IS HIGH THAT POOR FLYING WEATHER WILL TAKE PLACE DURING
MONDAY AND TUESDAY. THIS SYSTEM WILL LIKELY BRING WINTRY
PRECIPITATION TO MUCH OF THE AREA...BUT FURTHER UPDATES FROM THE
LONGER RANGE MODELS MAY IMPACT THE DETAILS ON PRECIPITATION TYPE
AND STORM TRACK. ANOTHER WEAK CLIPPER AREA OF LOW PRESSURE MAY
KEEP MVFR CONDITIONS ACROSS THE MOUNTAINS TUESDAY NIGHT INTO
WEDNESDAY WITH MAINLY VFR EAST OF THE BLUE RIDGE.
&&
.CLIMATE...
COLDEST AIR OF THE SEASON ARRIVES THIS WEEKEND. SEVERAL RECORD LOW
MAX TEMPERATURES AND LOW TEMPERATURES ARE POSSIBLE. BELOW ARE THE
CURRENT RECORDS FOR SATURDAY 2/13 AND SUNDAY 2/14.
SATURDAY 02/13/2016
SITE MINT YEAR LOMAX YEAR
KBLF 4 1988 19 1988
KDAN 11 1955 32 1981
KLYH 5 1979 9 1899
KROA 8 1917 18 1914
KRNK -4 1969 14 1955
SUNDAY 02/14/2016
SITE MINT YEAR LOMAX YEAR
KBLF 5 1971 16 1960
KDAN 15 1986 32 1986
KLYH 4 1899 24 1905
KROA 10 1943 26 1986
KRNK -2 1969 24 1986
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WIND CHILL ADVISORY FROM 11 PM THIS EVENING TO 10 AM EST
SUNDAY FOR VAZ007-009>020-022>024-032>035.
WINTER WEATHER ADVISORY UNTIL 7 AM EST SATURDAY FOR VAZ007-009-
015.
NC...WIND CHILL ADVISORY FROM 11 PM THIS EVENING TO 10 AM EST
SUNDAY FOR NCZ001-002-018.
WINTER WEATHER ADVISORY UNTIL 7 AM EST SATURDAY FOR NCZ001-018.
WV...WIND CHILL ADVISORY FROM 11 PM THIS EVENING TO 10 AM EST
SUNDAY FOR WVZ042>044-507.
WINTER WEATHER ADVISORY UNTIL 7 AM EST SATURDAY FOR WVZ042-043-
508.
WIND CHILL WARNING FROM 11 PM THIS EVENING TO 10 AM EST SUNDAY
FOR WVZ508.
&&
$$
SYNOPSIS...JH/MBS
NEAR TERM...JH/MBS
SHORT TERM...RAB
LONG TERM...AMS/RAB
AVIATION...JH/MBS/WP
CLIMATE...CF