VALLEY SUNDAY AND LOWERING THICKNESS VALUES
SUNDAY NIGHT FOR OUR AREA...ESPECIALLY IN NC. VERY LITTLE MOISTURE
ON GFS. HOWEVER...THE ECMWF HAS A DEEP CUT OFF UPPER LOW CROSSING
MISSOURI LATE SUNDAY NIGHT WITH ASSOCIATED COLD FRONT REACHING OUR
AREA NEAR 12Z MONDAY WITH GOOD SOUTHERN FLOW FROM THE GULF. THIS
LATEST EC IS QUITE DIFFERENT FROM THE PREVIOUS RUN AND THE SUNDAY
NIGHT PERIOD IS THE EXTRA PERIOD THAT DOES NOT COUNT IN THE CURRENT
SEVEN DAY FORECAST. THUS WE WILL SEE AS THE TIME GETS CLOSER TO
THAT POINT.
TEMPERATURES WILL BE A FEW DEGREES ABOVE NORMAL WITH SLIGHT FALLS
WITH PASSING SHORTWAVES.
&&
.AVIATION /11Z MONDAY THROUGH FRIDAY/...
AT KCLT...A SHARP DEWPOINT GRADIENT WAS LOCATED JUST TO THE
NORTHWEST OF THE AIRFIELD AT TAF ISSUANCE TIME. SOUTH OF THE BNDRY
WIDESPREAD DENSE FOG AND/OR VLIFR STRATUS HAS DEVELOPED. DRY AIR
WILL VERY SLOWLY PUSH TO THE SOUTH OVERNIGHT...BUT IT WILL BE A
COUPLE HOURS YET UNTIL THE DRY AIR WORKS IT/S WAY ACROSS THE
AIRFIELD WITH A WIND SHIFT TO THE NORTHWEST AND IMPROVING
CONDITIONS. SOME GUIDANCE TAKES EVEN LONGER TO BRING THE BNDRY
THROUGH...BUT BASED ON THE GUSTY WINDS AT KHKY AND 25 DEG DEWPOINT
AT KIPJ...I THINK THAT CONDITIONS WILL IMPROVE AT KCLT AFTER 0800
UTC.
AND ELSEWHERE...DRY AIR AND A WEAK COLD FRONT HAVE PUSHED THROUGH
KAVL AND KHKY WHICH WILL SEE NORTHWEST WINDS AND VFR CONDITIONS THE
REST OF THE NIGHT. OVER THE UPSTATE THE BNDRY HAS ONLY JUST MOVED
OFF THE ESCAPEMENT...AND IT WILL MOVE VERY SLOWLY...IF AT
ALL...OVER THE NEXT SEVERAL HOURS. DENSE FOG AND VLIFR CIGS HAVE
DEVELOPED IN THE MOIST AIR AHEAD OF THE BNDRY...AND THESE CONDITIONS
ARE EXPECTED TO PERSIST FOR THE NEXT 3 HRS OR SO AT THE THREE
UPSTATE AIRFIELDS. EVENTUALLY THE STRATUS AND FOG WILL BE PUSHED
SOUTH OF I-85...BUT A CONVERGENCE AXIS MAY HOLD IN LOW CIGS THROUGH
SUNRISE...ESPECIALLY AT KGMU AND KAND...WHICH IS WHAT I/VE DONE IN
THE TAFS. CONDITIONS THE REST OF THE DAY WILL BE GOOD WITH VFR
CONDITIONS AND LIGHT AND VARIABLE WINDS UNDER A RIDGE OF HIGH
PRESSURE.
OUTLOOK...LOW PRES WILL MOVE N FROM THE W GULF MON NIGHT AND INTO
THE FORECAST AREA TUE...BRINGING WIDESPREAD PRECIPITATION AND LOW
RESTRICTIONS. DRYING IS EXPECTED TUE NIGHT...WITH LINGERING NW FLOW
MOISTURE NEAR KAVL. CONDITIONS DRY OUT ACROSS THE AREA MID TO LATE
WEEK.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...DEO
NEAR TERM...MCAVOY
SHORT TERM...ARK
LONG TERM...DEO
AVIATION...MCAVOY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
329 AM EST MON DEC 26 2011
.SYNOPSIS...
A DEEPENING LOW PRESSURE SYSTEM IS EXPECTED TO TRACK NORTHEAST FROM
LOUISIANA TODAY AND REACH TENNESSEE AND KENTUCKY EARLY TUESDAY. HIGH
PRESSURE WILL BE BACK IN CONTROL FROM WEDNESDAY UNTIL THE WEEKEND
WHEN A COLD FRONT WILL APPROACH THE AREA FROM THE WEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
DENSE FOG AND LOW CLOUDS CONTINUES ACROSS THE CENTRAL AND EASTERN
PARTS OF THE UPSTATE AND THE EXTREME SRN PIEDMONT OF NORTH CAROLINA.
DRY AIR WILL CONTINUE TO WORK SLOWLY TO THE SOUTH...GRADUALLY MIXING
OUT THE FOG AND LOW CLOUDS. THE RUC AND NAM CONDENSATION PRESSURE
DEFICITS IMPLY LOW CLOUDS AND FOG ARE LIKELY TO PERSIST THE LONGEST
ACROSS GREENVILLE...SPARTANBURG AND LAURENS COUNTIES IN A WEAK LLVL
CONVERGENCE AXIS. WE HAVE A DENSE FOG ADVISORY OVER PARTS OF THE
AREA THROUGH 6 AM. IT WILL LIKELY NEED TO BE CANCELLED EARLY OVER
THE WESTERN UPSTATE AND NE GA...BUT IT STILL LOOKS GOOD FARTHER TO
THE EAST.
A STRONG UPPER LOW OVER WEST TEXAS THIS MORNING WILL EJECT QUICKLY
ACROSS THE LOWER MISSISSIPPI VALLEY TONIGHT AND LIFT ACROSS THE SRN
APPALACHIANS ON TUE AS AN OPEN WAVE. SFC CYCLOGENESIS WILL OCCUR
THIS AFTERNOON OVER THE NRN GULF...WITH THE LOW MOVING ACROSS THE
SRN APPS ON TUE. THE LATEST NAM AND GFS MODEL DATA IS A LITTLE
COLDER ACROSS THE NC MTNS TONIGHT. THE NAM HAS A LARGE AREA OF
1305-1310 METER 1000-850 MB THICKNESSES ACROSS THE SW AND CENTRAL
MTNS AT 0900 UTC...WHICH RETREAT UP ACROSS THE NRN MTNS BY 12 UTC.
NAM MODEL SOUNDINGS AT FRANKLIN AND CASHIERS IMPLY A PERIOD OF SLEET
AND FREEZING RAIN STARTING AFTER MIDNIGHT...WITH PCPN CHANGING TO
ALL RAIN TOWARD MORNING. THE GFS IS A LITTLE WARMER AND LOOKS TO BE
MAINLY LIQUID...WITH JUST A LITTLE SLEET AND A FEW PATCHES OF
FREEZING RAIN AT ONSET. IT STILL APPEARS THAT THE BULK OF THE
COOLING WITH THIS EVENT WILL BE DRIVEN BY OROGRAPHIC ASCENT AS A 60+
KT LLVL WARM SECTOR JET CROSSES THE MTNS. THIS SHOULD CONFINE
WINTRY PCPN TO SOUTH AND EAST REACHES OF THE MTNS...WITH DOWNSLOPE
HELPING TO WARM THE BNDRY LAYER CLOSER TO THE TN LINE. ALSO...NONE
OF THE MODELS IMPLY THAT WINTRY WX WILL HOLD ON ONCE THE HEAVIER
RAIN STARTS OWING TO A STRONG WARM NOSE UP AROUND H8. STILL...A
PERIOD OF LIGHT FREEZING RAIN AND SOME SLEET LOOKS LIKELY ACROSS
THE SW MTNS...AND ALSO ACROSS THE EASTERN ESCARPMENT OF THE BLUE
RIDGE UP IN THE NRN MTNS. AT THE MOST...THIS SHOULD BE A LOW END
ADVISORY LEVEL EVENT WITH ANY GLAZE CONFINED MAINLY TO ELEVATED
SFCS...AND IT WON/T AFFECT THE MTNS UNTIL WELL AFTER DARK TONIGHT.
THEREFORE...I/M GOING TO HOLD OFF ON ANY ADVISORIES WITH THIS
PACKAGE.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 315 AM MONDAY...THE MODELS ARE IN VERY GOOD AGREEMENT ON THE
POSITION OF THE UPPER SHORTWAVE AND SFC LOW PRESSURE AT 12Z TUESDAY.
AN IN SITU WEDGE WILL STILL BE IN PLACE ACRS THE CWFA...WITH SELY
850 MB WINDS OF 50-65 KTS ALOFT. VERY STRONG LLVL WAA AND MECHANICAL
LIFT WITH DEEP MOISTURE WILL BE AIDED BY DECENT QG FORCING AND UPPER
DIVERGENCE. SO A NEAR 100% POP TUESDAY MORNING SEEMS APPROPRIATE.
THERE ARE SOME DIFFERENCES AMONGST THE THERMAL PROFILES/SFC TEMPS
INVOF THE NC MTNS...HOWEVER...AS DYNAMICAL COOLING MAY LOCK IN
SUB-FREEZING TEMPS INVOF THE EAST-FACING SLOPES OF THE NRN MTNS/BLUE
RIDGE ESCARPMENT PAST DAYBREAK TUESDAY MORNING...WITH SOME
ADDITIONAL ICING POSSIBLE. ALL GUIDANCE HAS TEMPS WARMING ABOVE
FREEZING BY 15Z TUE...SO IT STILL LOOKS LIKE ANY TRAVEL PROBLEMS DUE
TO ICE SHUD BE OVER BY MIDDAY.
MIDDAY TUESDAY...THE LOW PRESSURE SYSTEM WILL QUICKLY LIFT
NORTHEASTWARD...WITH A PRIMARY LOW TRACKING ACRS THE TN/OH
VLYS...AND A TRIPLE POINT LOW TRACKING FROM CENTRAL GA TO CENTRAL NC
BY LATE AFTN. THE NAM/GFS/ECWMF ARE IN GOOD AGREEMENT ON THE GSP/CAE
CWFA BORDER AS AN APPROXIMATE TRACK OF THE TRIPLE POINT. SO INSTBY
LOOKS TO STAY SOUTH OF THE FA. THAT IS GOOD...BECAUSE HELICITY
VALUES WILL BE THRU THE ROOF...AND VERY LITTLE INSTBY WOULD BE
SUFFICIENT FOR A SMALL TORNADO/WIND THREAT. THE COLD/OCCLUDED FRONT
WILL CROSS FROM SW TO NE DURING THE AFTN HOURS...QUICKLY TAPERING
OFF POPS (EXCEPT FOR UPSLOPE ALONG TN/NC BORDER). STORM TOTAL QPF
LOOKS TO BE A SOLID 1-1.5" CWFA-WIDE...WITH 2-3" ALONG THE BLUE
RIDGE ESCARPMENT FROM HENDERSON COUNTY WEST. THERE COULD BE A FEW
HYDRO CONCERNS IN THOSE AREAS...BUT NOT WIDESPREAD ENUF TO WARRANT
ANY FLOOD WATCHES ATTM. WITH CLOUDS AND PRECIP...TEMPS WILL BE HELD
DOWN TO MAINLY MID-UPR 40S...EXCEPT ALONG SOUTHEAST EDGE NEAR THE
TMB/WEDGE BNDRY WHERE THEY WILL BE IN THE MID 50S OR HIGHER.
TUESDAY NIGHT...THERE WILL BE STRONG LLVL CAA ACRS THE FA IN THE
WAKE OF THE DEPARTING LOW...WITH GOOD NW FLOW UPSLOPE FORCING ALONG
THE TN/NC BORDER. BOTH THE NAM AND GFS IMPLY AT LEAST SCATTERED
SHOWER ACTIVITY...AND SNOW LEVELS SHUD FALL QUICKLY DURING THE
EVENING HOURS. SOME LOCATIONS MAY GET A QUICK INCH OR TWO
(ESPECIALLY ABOVE 3500 FT). THE SHOWER ACTIVITY LOOKS TO QUICKLY
TAPER OFF BY LATE WEDNESDAY MORNING. TEMPS ACRS THE ENTIRE AREA WILL
BE NEAR NORMAL.
WEDNESDAY AND WEDNESDAY NIGHT...GENERAL UPPER LEVEL TROFINESS
LINGERS...AS WEAK SFC HIGH PRESSURE BUILDS IN ACRS THE AREA. HIGH
TEMPS WILL BE AT OR A CATEGORY BELOW NORMAL AND OVERNIGHT LOWS
AROUND NORMAL UNDER GENERALLY CLEAR SKIES.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AT 220 AM EST MONDAY...ON THURSDAY THE MEDIUM RANGE MODELS SHOW
SURFACE HIGH PRESSURE CENTERED OVER THE GULF COAST AT THE FLORIDA
PANHANDLE WHILE CUTTING OFF ANY MOISTURE FLOW TO OUR REGION. FAIRLY
VIGOROUS VORT MAXES CROSSING THE AREA BUT NO MOISTURE TO WORK WITH.
ON FRIDAY...THE SURFACE HIGH SHIFTS EAST TO FLORIDA AND FARTHER EAST
AND SOME MOISTURE FLOW STARTS FROM THE WESTERN GULF AS A SHORTWAVE
DROPS DOWN FROM THE NORTHERN MISS VALLEY AND OHIO VALLEY. THIS
SHORTWAVE REACHES THE APPALACHIANS FRIDAY NIGHT AND SOME NORTHWEST
FLOW MOISTURE ALIGNS ALONG THE UPSLOPE REGION ALONG THE TENNESSEE
AND NORTH CAROLINA BORDER. THE FAST MOVING SHORTWAVE HAS AN AXIS
NEAR THE WV / VA BORDER BY 12Z SATURDAY ON BOTH THE GFS AND ECMWF.
IF THERE IS ANY SNOW SHOWERS FOR THE NC MOUNTAINS NEAR THE TN
BORDER...THIS WILL BE BRIEF AND MAINLY IN THE WEE HOURS OF SATURDAY
ACCORDING TO THE CURRENT TIMING OF THE MODELS. THE LATEST ECMWF
JUST CAME IN AND MUCH DRIER WITH ONLY A HINT OF ANY PRECIP FAR
NORTHERN MOUNTAINS AROUND 12Z SATURDAY. THE ENERGY WITH THE
SHORTWAVE IS FARTHER NORTH WITH THIS EC RUN. AT THIS POINT...NOT
FEELING CONFIDENT AND LEAVING NO MORE THAN 14 POP...JUST BELOW
SLIGHT POPS.
WEAK HIGH PRESSURE CENTERED OVER OUR REGION SATURDAY NIGHT. RETURN
FLOW BEGINS OVER THE LOWER MISS VALLEY SATURDAY NIGHT AHEAD OF THE
NEXT SHORTWAVE. THIS NEXT SHORTWAVE IS QUITE DIFFERENT ON THE GFS
COMPARED TO THE ECMWF. THE GFS HAS A STRONG SHORTWAVE CROSSING
GREAT LAKES AND OHIO VALLEY SUNDAY AND LOWERING THICKNESS VALUES
SUNDAY NIGHT FOR OUR AREA...ESPECIALLY IN NC. VERY LITTLE MOISTURE
ON GFS. HOWEVER...THE ECMWF HAS A DEEP CUT OFF UPPER LOW CROSSING
MISSOURI LATE SUNDAY NIGHT WITH ASSOCIATED COLD FRONT REACHING OUR
AREA NEAR 12Z MONDAY WITH GOOD SOUTHERN FLOW FROM THE GULF. THIS
LATEST EC IS QUITE DIFFERENT FROM THE PREVIOUS RUN AND THE SUNDAY
NIGHT PERIOD IS THE EXTRA PERIOD THAT DOES NOT COUNT IN THE CURRENT
SEVEN DAY FORECAST. THUS WE WILL SEE AS THE TIME GETS CLOSER TO
THAT POINT.
TEMPERATURES WILL BE A FEW DEGREES ABOVE NORMAL WITH SLIGHT FALLS
WITH PASSING SHORTWAVES.
&&
.AVIATION /09Z MONDAY THROUGH FRIDAY/...
AT KCLT...A SHARP DEWPOINT GRADIENT WAS LOCATED JUST TO THE
NORTHWEST OF THE AIRFIELD AT TAF ISSUANCE TIME. SOUTH OF THE BNDRY
WIDESPREAD DENSE FOG AND/OR VLIFR STRATUS HAS DEVELOPED. DRY AIR
WILL VERY SLOWLY PUSH TO THE SOUTH OVERNIGHT...BUT IT WILL BE A
COUPLE HOURS YET UNTIL THE DRY AIR WORKS IT/S WAY ACROSS THE
AIRFIELD WITH A WIND SHIFT TO THE NORTHWEST AND IMPROVING
CONDITIONS. SOME GUIDANCE TAKES EVEN LONGER TO BRING THE BNDRY
THROUGH...BUT BASED ON THE GUSTY WINDS AT KHKY AND 25 DEG DEWPOINT
AT KIPJ...I THINK THAT CONDITIONS WILL IMPROVE AT KCLT AFTER 0800
UTC.
AND ELSEWHERE...DRY AIR AND A WEAK COLD FRONT HAVE PUSHED THROUGH
KAVL AND KHKY WHICH WILL SEE NORTHWEST WINDS AND VFR CONDITIONS THE
REST OF THE NIGHT. OVER THE UPSTATE THE BNDRY HAS ONLY JUST MOVED
OFF THE ESCAPEMENT...AND IT WILL MOVE VERY SLOWLY...IF AT
ALL...OVER THE NEXT SEVERAL HOURS. DENSE FOG AND VLIFR CIGS HAVE
DEVELOPED IN THE MOIST AIR AHEAD OF THE BNDRY...AND THESE CONDITIONS
ARE EXPECTED TO PERSIST FOR THE NEXT 3 HRS OR SO AT THE THREE
UPSTATE AIRFIELDS. EVENTUALLY THE STRATUS AND FOG WILL BE PUSHED
SOUTH OF I-85...BUT A CONVERGENCE AXIS MAY HOLD IN LOW CIGS THROUGH
SUNRISE...ESPECIALLY AT KGMU AND KAND...WHICH IS WHAT I/VE DONE IN
THE TAFS. CONDITIONS THE REST OF THE DAY WILL BE GOOD WITH VFR
CONDITIONS AND LIGHT AND VARIABLE WINDS UNDER A RIDGE OF HIGH
PRESSURE.
OUTLOOK...LOW PRES WILL MOVE N FROM THE W GULF MON NIGHT AND INTO
THE FORECAST AREA TUE...BRINGING WIDESPREAD PRECIPITATION AND LOW
RESTRICTIONS. DRYING IS EXPECTED TUE NIGHT...WITH LINGERING NW FLOW
MOISTURE NEAR KAVL. CONDITIONS DRY OUT ACROSS THE AREA MID TO LATE
WEEK.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...DENSE FOG ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
GAZ018-026-028-029.
NC...DENSE FOG ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
NCZ070>072-082.
SC...DENSE FOG ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
SCZ004>014-019.
&&
$$
SYNOPSIS...DEO
NEAR TERM...MCAVOY
SHORT TERM...ARK
LONG TERM...DEO
AVIATION...MCAVOY
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1148 PM CST SUN DEC 25 2011
.AVIATION...
MVFR AT KAUS/KSAT/KSSF SHOULD STAY MVFR THROUGH THE NIGHT AS THE
UPPER LOW OVER WEST TEXAS SLOWLY BEGINS TO MOVE EAST. DECIDED TO
KEEP -DZ INTO THE I-35 TAFS...IT SHOULD BE VERY LIGHT AND NOT POSE
AN ICING PROBLEM UP TO ABOUT 10500 FT MSL AT THE FREEZING LEVEL.
DRIER AIR BEHIND THE UPPER LOW WILL BEGIN TO LIFT CIGS BY 15Z AND
YIELD CLEAR SKIES BY 00Z TUE.
&&
.PREV DISCUSSION... /ISSUED 946 PM CST SUN DEC 25 2011/
UPDATE...
PREVIOUS WEATHER FORECAST IS ON TRACK FOR THIS EVENING INTO MONDAY.
HOWEVER...LOWER MIN TEMPS FROM 1-3 DEGREES FROM WEST OF I 83 BASED
ON CURRENT TEMPS ACROSS THE VAL VERDE AND EDWARDS PLATEAU AREAS
AND THE LATEST NAM AND RUC SOLUTIONS. UPDATED ZONE OUT SHORTLY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 39 55 36 62 37 / 20 30 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 40 55 30 62 30 / 20 30 0 0 0
NEW BRAUNFELS MUNI AIRPORT 42 56 32 64 34 / 20 30 0 0 0
BURNET MUNI AIRPORT 34 52 31 59 32 / 20 20 - 0 0
DEL RIO INTL AIRPORT 30 59 34 64 35 / - - 0 0 0
GEORGETOWN MUNI AIRPORT 38 52 33 60 33 / 20 30 - 0 0
HONDO MUNI AIRPORT 40 59 28 65 31 / 10 10 0 0 0
SAN MARCOS MUNI AIRPORT 41 55 32 63 33 / 20 30 0 0 0
LA GRANGE - FAYETTE REGIONAL 43 53 36 62 35 / 30 50 10 0 0
SAN ANTONIO INTL AIRPORT 41 58 36 65 37 / 20 20 0 0 0
STINSON MUNI AIRPORT 43 59 34 66 36 / 20 20 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...26
SYNOPTIC/GRIDS...17
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
249 PM CST MON DEC 26 2011
.SHORT TERM...TONIGHT THROUGH THURSDAY
249 PM CST MON DEC 26 2011
THE MAIN FOCUS IN THE SHORT TERM IS ON THE PRECIPITATION CHANCES
TONIGHT INTO TOMORROW...FOLLOWED BY ANOTHER SYSTEM WEDNESDAY NIGHT
INTO THURSDAY.
GUSTY SOUTHWEST WINDS DEVELOPED TODAY AHEAD OF A COLD FRONT THAT
CURRENTLY EXTENDS SOUTH OF A SURFACE LOW IN FAR SOUTHWEST ONTARIO
DOWN THROUGH EASTERN MINNESOTA AND WESTERN IOWA TOWARD OMAHA. WITH
INCREASING CLOUD COVER AND A WEAKENING PRESSURE GRADIENT...WILL BE
ALLOWING THE WIND ADVISORY TO EXPIRE AT 3PM THIS AFTERNOON.
FURTHER ALOFT...A CUT OFF LOW OVER THE SOUTHERN PLAINS WAS
STARTING TO GET A KICK EASTWARD FROM A NORTHERN STREAM TROUGH
PROPAGATING EAST THROUGH SOUTHERN CANADA. A FEW SHOWERS HAVE
KICKED UP DOWN SOUTH CLOSER TO THE CUT OFF LOW AND SOME OF THE HI-
RES MESO MODELS DO CONTINUE TO SHOW SOME RETURNS GOING INTO THE
EVENING AHEAD OF THE COLD FRONT...MAINLY IN NORTHEAST IOWA AND
SOUTHWEST WISCONSIN. 26.18Z RUC SOUNDINGS OUT OF DBQ/BLR/MSN SHOW
A QUICK MOISTENING UP OF THE LOW LEVELS THIS EVENING TOWARD 23-03Z
BEFORE THE FRONT COMES THROUGH. THESE THERMAL PROFILES SHOW A WARM
LAYER OF 4C AROUND 925MB AND SURFACE TEMPERATURES ABOVE
FREEZING...SO ANY PRECIPITATION THAT FALLS TONIGHT AHEAD OF THE
FRONT SHOULD STAY IN LIQUID FORM AND NOT REFREEZE.
AFTER THIS FIRST COLD FRONT COMES THROUGH...A SECONDARY COLD FRONT
WILL SWING AROUND ON THE BACK SIDE OF THE SURFACE LOW AND COME
THROUGH THE REGION LATE TONIGHT INTO TOMORROW MORNING. 26.12Z
NAM/GFS AND 26.18Z RUC SOUNDINGS SHOW STEEPENING LOW LEVEL LAPSE
RATES WITH AN INCREASE IN MOISTURE RIGHT AROUND THE INVERSION.
WITH TEMPERATURES IN 925-875MB DROPPING INTO THE -8 TO -10C
RANGE...IT SHOULD BE COLD ENOUGH FOR ICE TO FORM. THERE IS NOT
MUCH FORCING TO WORK WITH...BUT THE COMBINATION OF STEEP LAPSE
RATES...MOISTURE AND ICE AVAILABLE...SHOULD SEE SOME LIGHT SNOW OR
FLURRIES WITH A DUSTING OF SNOW ACCUMULATION NOT OUT OF THE
QUESTION IN SPOTS. THE 26.12Z GFS APPEARS TO BE AN OUTLIER AT
THIS POINT WITH SHOWING MUCH DEEPER MOISTURE ACROSS ALL OF THE
REGION AND TRIES TO PUT DOWN A MUCH LARGER AREA OF ACCUMULATING
LIGHT SNOW THROUGH TOMORROW MORNING. WITH THE LOW LEVEL MIXING AND
A TIGHT PRESSURE GRADIENT IN PLACE...IT WILL BE ANOTHER WINDY DAY
TOMORROW WITH WIND GUSTS UP TO 30KTS IN THE HIGHER TERRAIN.
A RIDGE OF HIGH PRESSURE WILL MOVE THROUGH TOMORROW NIGHT INTO
EARLY WEDNESDAY BEFORE ANOTHER QUICK MOVING MID LEVEL TROUGH
PROPAGATES EAST ACROSS SOUTHERN CANADA THROUGH THE MAINLY ZONAL
FLOW. THE BETTER FORCING GOES NORTH TOWARD LAKE SUPERIOR WITH THE
LOW ON WEDNESDAY BUT ANOTHER QUICK MOVING TROUGH WILL UNDERCUT THIS
LOW AND BRING SOME BETTER CHANCES FOR PRECIPITATION WEDNESDAY
NIGHT INTO THURSDAY. PRECIPITATION TYPE WILL BE AN ISSUE WITH THE
THERMAL PROFILE LIKELY WARMING ENOUGH FOR IT TO POSSIBLY CHANGE
OVER TO RAIN...ESPECIALLY ALONG AND SOUTH OF THE I-94 CORRIDOR.
.LONG TERM...THURSDAY NIGHT THROUGH MONDAY
249 PM CST MON DEC 26 2011
CONFIDENCE IN THE LONG TERM REMAINS LOW GIVEN THE FAST ZONAL FLOW
AND THE DIFFERENCES THAT HAVE BEEN SHOWING UP BETWEEN THE
GEM/GFS/ECMWF. RUN TO RUN CONSISTENCY IN THE MODELS HAS NOT BEEN
VERY GOOD IN THE EXTENDED...SO HAVE TRIED TO HIGHLIGHT THE BEST
CHANCES FOR ANY OVERLAP BETWEEN THESE MODELS...WHICH IS MAINLY
THURSDAY NIGHT INTO FRIDAY. AFTER THIS SERIES OF SHORTWAVE TROUGHS
COME THROUGH...IT LOOKS LIKE THERE WILL BE A PERIOD OF RIDGING
GOING INTO THE WEEKEND. AFTER THIS RIDGE SHIFTS EAST BY SATURDAY
NIGHT...THE FOCUS IS ON ANOTHER TROUGH AND HOW DEEP IT DIGS SOUTH.
THE 26.12Z GFS KEEPS MORE OF A ZONAL FLOW AND OPEN WAVE WHILE THE
26.12Z ECMWF AND GEM START CARVING OUT A MUCH MORE AMPLIFIED WAVE.
THE IMPACT PRECIPITATION WISE FOR OUR AREA IS NOT MUCH AS IT
APPEARS THAT THE FOCUS WOULD BE OFF TO THE EAST.
&&
.AVIATION...THIS AFTERNOON THRU TUESDAY
1135 AM CST MON DEC 26 2011
A TIGHT PRESSURE GRADIENT...AHEAD OF A COLD FRONT IN THE EASTERN
DAKOTAS AND A LOW NEAR LK WINNIPEG WILL SPREAD ACROSS THE AREA THIS
AFTERNOON. BRISK SOUTHWEST WINDS OF 15-30KT G35+KTS CAN BE EXPECTED
ESPECIALLY AT THE HIGHER TERRAIN SITES /KRST/KAUM/ETC./ THRU MUCH OF
THE AFTERNOON DURING PEAK HEATING/MIXING. GRADIENT WILL RELAX LATE
THIS AFTERNOON/EVENING WITH FRONTAL PASSAGE...WITH WINDS BECOMING
WEST DURING THE EVENING THEN NORTHWEST OVERNIGHT AND FOR TUE. CIGS/
VSBYS WILL REMAIN GOOD VFR THIS AFTERNOON/EVENING. SOME LOWER LEVEL
MOISTURE/CLOUDS/WEAK LIFT WILL SPREAD ACROSS THE TAF SITES BEHIND
THE FRONT FOR LATER TONIGHT/WED MORNING. MVFR CIGS EXPECTED WITH
THESE CLOUDS BEHIND THE FRONT LATE TONIGHT AND MUCH OF WED MORNING.
MAY BE ENOUGH LIFT FOR SCT FLURRIES AT/AROUND THE TAF SITES AND
INCLUDED A VCSH MENTION AT BOTH KRST/KLSE IN THE 08-18Z TIME-FRAME
AS THE 925-700MB TROUGH AXIS PASSES. GRADIENT TIGHTENS AGAIN TUE
MORNING AND FOR TUE AFTERNOON WITH BRISK NORTHWEST WINDS OF 15-25KT
G30KTS...AGAIN STRONGEST AT THE HIGHER ELEVATION SITES. MVFR CLOUDS/
CIGS TO BREAK UP/ADVECT OUT OF THE AREA WITH SUBSIDENCE LATE TUE
MORNING/AFTERNOON...WITH ANY WARMING/DEEPER MIXING TUE AFTERNOON
EXPECTED TO ADD TO THE GUSTINESS OF THE WINDS UNTIL THE GRADIENT
RELAXES LATE IN THE AFTERNOON/TUE EVENING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
249 PM CST MON DEC 26 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
142 PM CST MON DEC 26 2011
.SHORT TERM...
TONIGHT AND TUESDAY - CONFIDENCE...MEDIUM
WATER VAPOR/RUC COMBO SHOWS SOUTHERN STREAM ENERGY CRUISING THROUGH
NRN TX WITH NORTHERN STREAM WAVE TRAVERSING EAST FROM ND INTO NRN
MN. SOME INCREASE IN MOISTURE NOTED OUT AHEAD OF SOUTHERN WAVE.
MID/HIGH CLOUDS RACING NORTHEAST FROM ERN IA AND CENTRL IL WILL
OVERSPREAD SRN WI THIS EVENING. LOW LEVELS WILL BE SLOW TO SATURATE
PER RUC AND NAM BUFKIT SOUNDINGS. IN FACT...THE LOW LEVELS REALLY DO
NOT MOISTEN UP UNTIL THE COLD AIR ADVECTION REGIME KICKS IN ON
TUESDAY. QPF TIED MORE TO RIGHT REAR QUADRANT AND THIS KEEPS PRECIP
JUST TO OUR SE. MODELS GENERATE LIGHT QPF TUESDAY IN COLD AIR
ADVECTION REGIME...WITH NORTHERN STREAM MID LEVEL TROUGH PASSAGE.
WILL GO WITH THE LOW POP/SHSN IDEA WITH MORE OF A FLURRY SCENARIO IN
THE AFTERNOON. OVERALL DEPTH OF MOISTURE LOOKS UNIMPRESSIVE. LOW
LEVELS A BIT MORE MOIST IN THE CAA REGIME. TEMPS WILL BE NOTICEABLY
COOLER WITH THE CLOUD COVER/GUSTY NW WINDS AND 925 TEMPS DROPPING TO
-6 TO -8C.
.TUESDAY NIGHT AND WEDNESDAY...FORECAST CONFIDENCE...MEDIUM.
AS THE STRONG SHORTWAVE MOVES OFF...A MORE WEST/NORTHWEST FAST FLOW
IS EXPECTED IN THE MID/UPPER LEVELS. ONE WEAK SHORTWAVE MOVES
ACROSS SOUTHERN WISCONSIN WEDNESDAY MORNING WHILE A SECOND
STRONGER SHORTWAVE APPROACHES LAKE SUPERIOR AREA LATE WEDNESDAY
AFTERNOON. THE PRECIPITATION FROM THIS SHORTWAVE IS EXPECTED TO
REMAIN TO THE NORTH.
A SURFACE HIGH WILL CROSS WISCONSIN TUESDAY NIGHT BEFORE WARM AIR
ADVECTION TAKES HOLD ON WEDNESDAY. LOW LEVELS ARE DRY WITH ONLY
MID LEVELS SATURATING ON WEDNESDAY WITH THE APPROACHING SHORTWAVE.
.WEDNESDAY NIGHT AND THURSDAY...FORECAST CONFIDENCE...MEDIUM.
THE SHORTWAVE MOVES ACROSS THE UPPER GREAT LAKES WEDNESDAY NIGHT
AS A BROAD ZONAL FLOW DEVELOPS IN THE MID/UPPER LEVELS AS A RATHER
WEAK SHORTWAVE MOVES TOWARDS NORTHERN MINNESOTA. ASSOCIATED WEAK
SURFACE LOW SHOULD REACH NORTHWEST MINNESOTA THURSDAY AFTERNOON
WITH SOUTH FLOW DEVELOPING ACROSS SOUTHERN WISCONSIN.
.LONG TERM...
.FRIDAY THROUGH SUNDAY...FORECAST CONFIDENCE MEDIUM.
THE MILD WEATHER PATTERN CONTINUES AS THE MODELS CONTINUE THE
PARADE OF WEAK SHORTWAVES IN THE FAST ZONAL FLOW. ONE SHORTWAVE
MOVES ACROSS FRIDAY. 12Z GFS TAKES A FAST SHORTWAVE JUST NORTH OF
LAKE SUPERIOR WHILE THE 00Z ECMWF BEGINS TO DIG A MAJOR TROUGH
OVER THE PLAINS. FOR NOW WILL LEAN MORE TOWARD THE GFS.
A WEAK TROUGH OF LOW PRESSURE MOVES ACROSS WISCONSIN FRIDAY WHILE
WITH A WEAK RIDGE ON THE 12Z GFS. MOTH MODELS DEVELOP A TROUGH
OVER THE WESTERN GREAT LAKES SUNDAY...BUT GFS IS FARTHER NORTH
WITH THE 00Z ECMWF EXTENDING THE TROUGH INTO SOUTHEAST MISSOURI
AND STRENGTHENS IT. NOT READY TO BUY IN TO THIS SCENARIO AND WILL
TREND TOWARD THE 12Z GFS. NEW 12Z ECMWF HAS NOW TRENDED TOWARD
THE 12Z GFS.
.MONDAY...FORECAST CONFIDENCE MEDIUM.
AS THE UPPER TROUGH DEEPENS ON THE 00Z ECMWF IT TAKES A STRONG
SURFACE LOW NORTH INTO LOWER MICHIGAN. MEANWHILE THE GFS QUICKLY PUSHES
A SURFACE LOW OFF THE SOUTHEAST CANADIAN COAST WITH HIGH PRESSURE
BUILDING OVER THE UPPER MIDWEST.
THE GFS IS MORE CONSISTENT WITH THE 06Z DGEX AND WILL TREND MORE
TOWARD THESE MODELS. NEW 12Z ECMWF HAS NOW TRENDED MORE TOWARD
THE 12Z GFS BUT THE 12Z ECMWF STILLS DIGS THE MID/UPPER TROUGH
MORE ACROSS THE EASTERN GREAT LAKES. PREFER THE LOWER APMPLITUDE
12Z GFS/06Z DGEX.
&&
.AVIATION/00Z TAFS/...
MID DECK INCREASES THIS EVENING AS SOUTHWEST
FLOW BRINGS MOISTURE UP AND OUT AHEAD OF SOUTHERN STREAM UPPER LOW.
LOWER LEVELS NOT PROGGD TO SATURATE UNTIL COLD AIR ADVECTION REGIME
KICKS IN ON TUESDAY. WILL GO WITH MVFR CEILINGS. SPOTTY LIGHT PRECIP
IS POSSIBLE THOUGH NOT EXPECTING ANYTHING MAJOR WITH COLUMN MOISTURE
LOOKING MEAGHER.
&&
.MARINE...
STRONG SOUTHWEST GRADIENT BETWEEN LOW CROSSING SOUTHERN CANADA
AND HIGH IN EASTERN US. WINDS HAVE RAMPED UP AND GUSTING TO SCA
CRITERIA.
WINDS MAY DROP BRIEFLY BELOW ADVISORY CRITERIA LATE TONIGHT AND
EARLY TUESDAY BEFORE STRONG PRESSURE RISES AND COLD ADVECTION BEHIND
COLD FRONT KICK IN AND KEEP THINGS BRISK INTO TUESDAY EVENING.
SMALL CRAFT ADVISORY RUNS FROM TODAY THROUGH EARLY WEDNESDAY FOR
SIMPLICITY.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 9 AM CST WEDNESDAY FOR LMZ643>646.
&&
$$
TONIGHT/TUESDAY AND AVIATION/MARINE...COLLAR
TUESDAY NIGHT THROUGH MONDAY...HENTZ
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSONVILLE FL
940 AM EST MON DEC 26 2011
.UPDATE...COLD FRONT IS JUST S OF THE AREA WITH HIGH PRES CENTERED
OVER THE TN VALLEY AREA. MEAN LAYER HIGH PRES RIDGE IS W OF THE
AREA AND WILL BUILD IN THROUGH THE DAY RESULTING IN WEAK SUBSIDENCE
PATTERN INTO LATE AFTN. SATELLITE IMAGERY SHOWS MULTILAYERED
CLOUDS ACROSS THE AREA WITH RUC INDICATING DEEPEST MOISTURE
RESIDING OVER NE FL THROUGH THE DAY WITH LLVL FLOW NE BECOMING E.
BREEZY CONDS LIKELY TO PERSIST ALONG THE COASTAL AREAS MOST OF
THE DAY.
REST OF TODAY...MOSTLY CLOUDY CONDS EXPECTED TO PREVAIL ACROSS NE
FL AS THE FRONT TO THE S BECOMES STATIONARY AND FLOW ALOFT STARTS
TO VEER AND RESULT IN ISENTROPIC ASCENT. MEANWHILE...PARTLY CLOUDY
CONDS WILL DEVELOP OVER SE GA THOUGH BROKEN HIGH CLOUDS LIKELY
THROUGH THE DAY THANKS TO UPSTREAM SYSTEM OVER TX AND LOWER MS
VALLEY. SOME LIGHT RAIN WILL BE POSSIBLE BY LATE AFTN OVER THE WRN
ZONES WITH THE APPROACH OF THE TROUGH TO OUR W BUT WILL PROBABLY
KEEP SILENT 10% FOR NOW. A FEW LIGHT SHOWERS POSSIBLE ALONG THE
COAST S OF JAX DUE TO MOIST NE FLOW...OTHERWISE DRY FCST TODAY.
TEMPS WILL STRUGGLE THROUGH THE 60S MOST AREAS WITH LOWER 70S
ANTICIPATED S/SW ZONES...WITHIN A FEW DEGREES OF CLIMATE.
&&
.AVIATION...VFR CONDS EXPECTED TO PREVAIL THOUGH SOME BRIEF OCCASIONS
OF MVFR CIGS POSSIBLE AT GNV OVER THE NEXT FEW HRS. NELY WINDS
WILL BE AROUND 10-15G25KT. CIGS LOOK TO STAY AOA 5 KFT THROUGH
00Z...THEN MAINLY MVFR CIGS AND VSBY WITH SHOWERS DEVELOPING AS A
COLD FRONT APPROACHES. LLWS ALSO EXPECTED LATE.
&&
.MARINE...MODERATE NNE BREEZE OVER THE WATERS WITH OBS SHOWING 15-20
KT. WINDS EXPECTED TO SHIFT TO NE AND THEN E AS HIGH PRES N OF THE
AREA MOVES EWD. SEAS ARE 1-2 FT LOWER COMPARED TO GUID/FCST RIGHT
NOW BUT SHOULD NUDGE UP THROUGH THE DAY DUE TO N-NELY FETCH. CURRENT
HEADLINES LOOK ON TRACK AT THIS TIME.
RIP CURRENTS: INCREASED SURF CONDS EXPECTED FROM AROUND 2-3 FT TO
NEAR 3-5 FT AND WILL RESULT IN MODERATE RISK TODAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 64 52 64 38 / 10 80 80 10
SSI 61 60 68 44 / 10 50 80 20
JAX 65 59 72 43 / 10 50 80 20
SGJ 66 65 73 47 / 10 40 80 20
GNV 70 59 72 42 / 10 40 80 20
OCF 72 60 74 45 / 10 30 80 20
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 8 AM EST WEDNESDAY FOR ALTAMAHA SOUND
GA TO FERNANDINA BEACH FL 20 NM TO 60 NM OFFSHORE-
FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM OFFSHORE-
ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM OFFSHORE.
&&
$$
SHASHY/WALKER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
238 AM MST WED DEC 28 2011
.SYNOPSIS...
222 AM MST WED DEC 28 2011
LATEST SATELLITE IMAGERY AND RUC ANALYSIS SHOW AN UPPER LEVEL RIDGE
OVER THE WEST COAST...WITH AREAS OF CLOUDS AND PRECIPITATION MOVING
ALONG THE NORTHERN PERIPHERY. OVER THE HIGH PLAINS A SHORT WAVE
TROUGH WAS PROGRESSING SOUTHEAST INTO TEXAS. AT THE SURFACE A
TROUGH WAS MOVING THROUGH THE TRI-STATE AREA WITH SOUTHWEST WINDS
TURNING TO THE NORTHWEST BEHIND THE TROUGH.
JTL
&&
.SHORT TERM (TODAY-FRIDAY)...
222 AM MST WED DEC 28 2011
ABOVE NORMAL TEMPERATURES WILL BE THE FOCUS FOR THIS PERIOD.
TODAY...NORTHWEST FLOW WILL CONTINUE OVER THE AREA WITH A MINOR
SHORT WAVE TROUGH MOVING THROUGH THE FLOW DURING THE DAY. WITH THE
RIGHT EXIT REGION OF THE JET MOVING IN AND SOME MOISTURE MOVING
THROUGH THE FLOW...AM NOT ANTICIPATING ANYTHING MORE THAN SOME
CLOUDS. WINDS WILL BE BREEZY TODAY AS SOME OF THE STRONGER WINDS
ABOVE THE SURFACE ACCOMPANYING THE TROUGH ARE ABLE TO MIX DOWN.
TEMPERATURES WILL BE WARMER THAN YESTERDAY AS 850MB TEMPERATURES
WARM BEHIND THE TROUGH.
THURSDAY AND FRIDAY...A COUPLE OF SHORT WAVE TROUGHS WILL MOVE
THROUGH THE NORTHWEST FLOW...PLACING THE RIGHT ENTRANCE AND LEFT
EXIT REGIONS OF THE JET OVER THE TRI-STATE AREA. SOME 700-300MB
FRONTOGENESIS WILL MOVE OVER THE AREA WITH THESE TROUGHS. MODELS
DISAGREE WITH HOW MUCH MOISTURE IS PRESENT AS THE TROUGHS MOVE
THROUGH...ESPECIALLY FOR THE TROUGH COMING THROUGH FRIDAY MORNING.
SREF PRECIPITATION PROBABILITIES ARE ZERO WHILE THE GEFS DOES SHOW
A SMALL CHANCE FOR SOME MINIMAL PRECIPITATION IN THE
BENKLEMEN...MCCOOK AND OBERLIN AREA. WITH SUCH DISAGREEMENT AMONG
MODELS...WILL LEAVE FORECAST DRY FOR NOW.
WINDS WILL STRENGTHEN THURSDAY AS STRONG UPPER LEVEL WINDS
ACCOMPANY THE TROUGH THROUGH THE AREA AND ARE ABLE TO MIX TO THE
SURFACE. CURRENTLY LOOKS LIKE AREAS NORTH OF HIGHWAY 36 WILL HAVE
THE BEST MIXING AND STRONGEST WINDS...WITH GUSTS UP TO 35 MPH
POSSIBLE. THE WINDS WILL DECREASE AT SUNSET. FRIDAY WINDS WILL BE
LIGHT AS A SURFACE HIGH PRESSURE MOVES INTO THE AREA AHEAD OF A
DEVELOPING SURFACE TROUGH OVER COLORADO.
TEMPERATURE-WISE THURSDAY WILL BE THE WARMEST...WITH HIGHS
REACHING THE LOWER 60S THANKS TO 850MB TEMPERATURES WARMING AS THE
TROUGH MOVES THROUGH. FRIDAY TEMPERATURES WILL BE A FEW DEGREES
COOLER AS COOLER AIR BEHIND THE TROUGH FROM FRIDAY MORNING MOVES
INTO THE AREA.
JTL
.LONG TERM (SATURDAY-TUESDAY)...
222 AM MST WED DEC 28 2011
NEW ECMWF IS MORE IN LINE WITH THE GFS SATURDAY BRINGING A
SHORTWAVE TROUGH AND COLD FRONT THROUGH THE FORECAST AREA.
DEPENDING ON THE TIMING OF THE FRONT...TEMPERATURES MAY WARM
NICELY IN THE MORNING. CURRENT PROJECTIONS OF FRONTAL PASSAGE IN
THE AFTERNOON...THOUGH...WILL LIMIT TOO MUCH WARMING...AND WILL
CONTINUE WITH HIGH TEMPERATURES IN THE LOWER TO MID 50S. ECMWF
CONTINUES TO DEPICT LIGHT PRECIPITATION SATURDAY NIGHT OVER THE
NORTHERN SECTION OF AREA...BUT AGREE WITH OTHER MODELS ABOUT THE
LIMITED AMOUNT OF MOISTURE SO WILL CONTINUE WITH A DRY FORECAST.
STRONG 500 MB RIDGE WILL THEN BUILD OVER THE WESTERN UNITED
STATES BEGINNING SUNDAY AND CONTINUING THROUGH THE EARLY PART OF
NEXT WEEK. THE QUESTION WILL BE HOW FAR EAST THE RIDGE AXIS MOVES
AND HOW STRONG THE HEIGHT RISES WILL BE. THE ECMWF IS SLIGHTLY
STRONGER WITH THE RIDGE AXIS...BUT ALSO FURTHER WEST OF THE GFS.
THIS PLACES STRONG NORTH TRAJECTORIES OVER THE AREA MONDAY FOR
SOME COLD AIR ADVECTION. THE GFS IS FURTHER EAST AND WOULD SUPPORT
WARMER TEMPERATURES. REGARDLESS...BOTH MODELS PROG 500 MB HEIGHTS
OVER 576 METERS BY TUESDAY FOR ABOVE NORMAL TEMPERATURES AND
CONTINUED DRY.
&&
.AVIATION...
942 PM MST TUE DEC 27 2011
VFR CONDS WILL PREVAIL AT BOTH TERMINALS THROUGH THE NEXT 24 HOURS.
NORTHWESTERLY WINDS TO BEGIN THE PERIOD WILL SLOWLY SWITCH TO THE
WEST AND SOUTHWEST BY WEDNESDAY AFTERNOON. MID/HIGH CLOUDS WILL BE ABUNDANT
AS UPPER LEVEL DISTURBANCES MOVE OVER THE REGION.
BAS
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
332 PM CST MON DEC 26 2011
.DISCUSSION...
DAYS 1-2...
THE MAIN FORECAST FOCUS WILL BE ON TEMPERATURES DURING THE PERIOD.
WV IMAGERY AND 12Z UPPER AIR ANALYSIS INDICATE AN UPPER LEVEL
TROUGH OF LOW PRESSURE EDGING SLOWLY EAST ACROSS THE SOUTH PLAINS
OF WESTERN OKLAHOMA AND NORTH TEXAS. NEAR THE SURFACE, A TROUGH OF
LOW PRESSURE EXTENDS FROM THE DAKOTAS SOUTHWARD ACROSS WESTERN
NEBRASKA INTO EXTREME EASTERN COLORADO.
SHORT RANGE MODELS INDICATE THE UPPER LEVEL TROUGH MOVING FURTHER
EAST INTO THE LOWER MISSISSIPPI RIVER VALLEY TONIGHT THEN LIFTING
NORTHEAST ALONG THE EASTERN SEABOARD THROUGH TUESDAY NIGHT. THIS
WILL GIVE WAY TO A NORTHWESTERLY FLOW ALOFT ACROSS THE WESTERN
HIGH PLAINS THROUGH THE END OF THE PERIOD WEDNESDAY. ONE MINOR
SHORTWAVE WILL TRAVEL SOUTHEAST ACROSS THE WESTERN HIGH PLAINS
TUESDAY NIGHT BUT NO PRECIP IS EXPECTED ACROSS WESTERN KANSAS WITH
VERY LITTLE MOISTURE AVAILABLE FOR IT TO WORK WITH. TEMPERATURES
ARE EXPECTED TO BE NEAR NORMAL DURING THE PERIOD. FOR TONIGHT, AN
UPPER LEVEL SHORTWAVE TRANSITIONING EAST ACROSS THE NORTHERN
PLAINS WILL HELP PUSH A COLD FRONT SOUTHEAST ACROSS WESTERN KANSAS
THIS EVENING TURNING WINDS NORTHWESTERLY ACROSS WESTERN KANSAS AND
BRINGING SLIGHTLY COOLER AIR INTO THE REGION. ALTHOUGH, DOWNSLOPING
MAY KEEP TEMPERATURES FROM VARYING TOO MUCH TONIGHT IN COMPARISON
TO THIS MORNING, BUT SITES DOWNWIND OF THE LINGERING SNOWPACK WILL
LIKELY SEE LOW TEMPERATURES DROP SOMEWHAT. LOOK FOR LOWS DOWN
INTO THE TEENS(C) AND 20S(C) ACROSS MUCH OF SOUTHWEST KANSAS WITH
THE COOLEST TEMPERATURES ASSOCIATED WITH THE SNOWPACK.
FOR TUESDAY, LEE SIDE TROUGHING WILL QUICKLY REDEVELOP ACROSS
EASTERN COLORADO HELPING TO TURN SURFACE WINDS BACK TO THE WEST AND
SOUTHWEST BY EARLY TUESDAY AFTERNOON. THE NAM, GFS, AND UKMET SHOW
H85 TEMPERATURES RANGING FROM AROUND 0C ACROSS CENTRAL KANSAS TO
NEAR 2C IN OUR FAR SOUTHWEST. EXPECT HIGHS IN THE MID TO UPPER
40S(F) IN SOUTH CENTRAL KANSAS WITH HIGHS STRUGGLING TO REACH NEAR
40F IN WEST CENTRAL KANSAS WHERE SNOWPACK WILL REMAIN PRESENT.
SIMILAR TEMPERATURES ARE EXPECTED OVER THE COURSE OF TUESDAY NIGHT
AND WEDNESDAY WITH A GENERAL DOWNSLOPING REGIME REMAINING IN
PLACE ACROSS WESTERN KANSAS THROUGH AT LEAST MID WEEK.
DAYS 3-7...
LONG RANGE MODELS LOOK COMPARABLE INTO FRIDAY WITH DRY NORTHWEST
FLOW ALOFT AND MILD 850 MB TEMPS AROUND 10 TO 14C. AFTER THAT THE
ECMWF PUSHES A STRONG UPPER LEVEL TROUGH ACROSS THE NORTHERN AND
CENTRAL CONUS FOR NEXT WEEKEND WHILE OTHER MODELS HAVE MORE RIDGING
AND LESS COOLING. THE GFS AND EC AGREE WITH A COLD FRONT ON SUNDAY
BUT THE EC HAS A MUCH COLDER AIRMASS WITH 850 TEMPS FALLING INTO THE
-3C WITH THE GFS AT 4C. THEN BY MONDAY IF THE EC WORKS OUT IT SHOWS
SOME ARCTIC AIR INVADING ON MONDAY. THE NEW 144 HR RUN OF THE UKMET
NOW LOOKS EVEN COLDER AND FASTER FOR THE COLDER AIRMASS THAN EVEN
THE ECMWF. FOR NOW WITH THE BLENDED SOLUTIONS HOLDING ON TO MORE OF
THE WARMER GFS RUNS WILL CONTINUE WITH COOLER TEMPS FOR THE WEEKEND
WITH THE WEAKER COLD FRONT, BUT NOT AS COLD AS THE UK/ECMWF AT THIS
TIME.
AS FOR TEMPS GO LOOK FOR LOWS IN THE UPPER 20S THURSDAY MORNING
WARMING INTO THE LOWER 30S INTO THE WEEKEND. HIGHS WILL WARM INTO
THE LOW TO MID 50S INTO FRIDAY WITH A COOLING TREND ON THE WEEKEND
INTO THE 40S. THE COLD GROUND AND SNOW PACKED AREAS WILL BE FADING
RAPIDLY AWAY BY THURSDAY WITH HIGHS ONLY SLIGHTLY COOLER IN THE ANY
REMAINING SNOWPACK.
&&
.AVIATION...
FOR THE 18Z TAF ISSUANCE...
A NORTHERN BRANCH SHORTWAVE TROUGH WILL MOVE ACROSS THE NORTHERN
HIGH PLAINS AND INTO THE UPPER MIDWEST BY 12Z TUES. THIS SYSTEM WILL
PUSH A DRY COLD FRONT ACROSS WESTERN KANSAS THIS EVENING. WINDS WILL
SHIFT FROM THE WEST AND SOUTHWEST TO THE NORTHWEST AT 10 TO 15 KTS
BY 00Z TO 03Z AT THE TAF SITES. THE 18Z RUN OF THE HRRR AND THE NEW
18Z NAM AND RUC HAVE THE FRONT A BIT DELAYED THAN THE EARLIER NAM
RUN. VFR CONDITIONS ARE EXPECTED WITH ONLY SOME SCT HIGH LEVEL
CIRRUS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 17 40 20 47 / 0 0 0 0
GCK 13 37 18 43 / 0 0 0 0
EHA 20 40 22 47 / 0 0 0 0
LBL 13 42 18 48 / 0 0 0 0
HYS 18 38 20 45 / 0 0 0 0
P28 23 47 25 52 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
FN32/06/06
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1230 PM MST MON DEC 26 2011
.UPDATE...
1225 PM MST MON DEC 26 2011
SFC TROUGH MOVING ACROSS THE CWA HAS ALLOWED TEMPS TO WARM MORE
THAN PREVIOUSLY THOUGHT. HAVE UPDATED THE FCST TO REFLECT THE WARMING
AND BUMPED UP THE SFC WINDS IN ORDER TO BETTER AGREE WITH OBS.
05
&&
.SYNOPSIS...
LATEST IR SATELLITE IMAGERY AND RUC ANALYSIS SHOWED A SHORT WAVE
TROUGH MOVING ACROSS THE NORTHERN CONUS WITH AREAS OF CLOUDS AHEAD
OF IT. FURTHER SOUTH THE CLOSED LOW CONTINUES TO SPIN OVER EASTERN
NEW MEXICO AND WESTERN TEXAS. CURRENT RADAR SHOWS ECHOES OVER
SOUTHWEST KANSAS AS SOME MOISTURE MOVES UP FROM THE CLOSED LOW...WITH
A FEW SPRINKLES AND LIGHT SNOW REACHING THE GROUND. AT THE SURFACE
A HIGH PRESSURE WAS PROGRESSING OUT OF THE TRI-AREA AHEAD OF THE
PRE-FRONTAL TROUGH THAT WILL MOVE THROUGH TODAY.
JTL
&&
.SHORT TERM (TODAY-WEDNESDAY)...
227 AM MST MON DEC 26 2011
TEMPERATURES WILL BE THE MAIN FOCUS FOR THIS PERIOD.
TODAY A PRE-FRONTAL SURFACE TROUGH WILL MOVE THROUGH THE AREA DURING
THE DAY...CAUSING THE SOUTHWEST WINDS TO SHIFT TO THE NORTHWEST.
WITH LITTLE MOISTURE TO WORK WITH...AM ONLY ANTICIPATING STRONGER
WINDS AND A FEW CLOUDS BEHIND THE TROUGH. HIGH TEMPERATURES WILL BE
SIMILAR TO YESTERDAY.
TUESDAY THROUGH WEDNESDAY...ANOTHER SURFACE AND UPPER LEVEL TROUGH
WILL MOVE THROUGH THE TRI-STATE AREA DURING THE LATE AFTERNOON AND
EVENING HOURS. SOUNDINGS AND CROSS SECTIONS SHOW UPPER LEVEL
MOISTURE INCREASING AS THE TROUGH MOVES THROUGH. THERE ALSO IS SOME
INSTABILITY PRESENT...ALONG WITH LIFT FROM FRONTOGENESIS AND WARM
AIR ADVECTION AS THE TROUGH MOVES THROUGH. HOWEVER A NARROW LAYER
OF MUCH DRIER AIR BETWEEN THE SURFACE AND THE MOISTURE MAY HINDER
ANY PRECIPITATION FROM REACHING THE GROUND. CANNOT COMPLETELY RULE
OUT SOMETHING FROM REACHING THE GROUND SO WILL ADD A MENTION OF
FLURRIES FOR AREAS NORTH OF A BENKELMAN TO HILL CITY LINE. TEMPERATURES
WILL BE COOLER TUESDAY AS SLIGHTLY COOLER AIR WILL MOVE IN BEHIND
MONDAY/S TROUGH. WEDNESDAY THE ENVIRONMENT DRIES OUT BEHIND THE
TROUGH. TEMPERATURES WILL BE WARMER AS 850MB TEMPERATURES
INCREASE.
JTL
.LONG TERM (THURSDAY-SUNDAY)...
227 AM MST MON DEC 26 2011
A SERIES OF WEAK SHORT WAVE TROUGHS WILL MOVE ACROSS
THE HIGH PLAINS THROUGH THE REST OF THE WEEK...BUT BEST LIFT AND
MOISTURE WILL BE FAR NORTH OF THE FORECAST AREA. MODELS INDICATE THE
BEST CHANCE FOR ANY PRECIPITATION WOULD BE TOWARD THE END OF THE
PERIOD...SATURDAY NIGHT/SUNDAY MORNING. MODELS DIFFER IN THEIR
SOLUTIONS AT THAT TIME. THE ECMWF IS FURTHER SOUTH AND WEST WITH
DYNAMICS AND MOISTURE THAN THE GFS. WITH ENSEMBLES SHOWING WIDE
VARIABILITY AFTER 120 HOURS...WILL STAY THE COURSE OF A DRY
FORECAST. TEMPERATURES WILL BE ABOVE NORMAL WITH DAILY MAXIMUM
TEMPERATURES MAINLY IN THE 50S.
&&
.AVIATION...
1013 AM MST MON DEC 26 2011
FOR THE 18Z TAFS...VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD
AT BOTH TERMINALS. A COLD FRONT WILL MOVE THROUGH THE TERMINALS
DURING THE FIRST HOUR OF THE PERIOD...CAUSING WINDS TO SHIFT TO
THE NORTHWEST AND BECOME STRONGER. BEHIND THE FRONT...WINDS WILL
INCREASE FURTHER AND VEER SLIGHTLY MORE. WINDS WILL DECREASE NEAR
00Z AS DAYTIME MIXING ENDS.
CJS
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1013 AM MST MON DEC 26 2011
.SYNOPSIS...
LATEST IR SATELLITE IMAGERY AND RUC ANALYSIS SHOWED A SHORT WAVE
TROUGH MOVING ACROSS THE NORTHERN CONUS WITH AREAS OF CLOUDS AHEAD
OF IT. FURTHER SOUTH THE CLOSED LOW CONTINUES TO SPIN OVER EASTERN
NEW MEXICO AND WESTERN TEXAS. CURRENT RADAR SHOWS ECHOES OVER
SOUTHWEST KANSAS AS SOME MOISTURE MOVES UP FROM THE CLOSED LOW...WITH
A FEW SPRINKLES AND LIGHT SNOW REACHING THE GROUND. AT THE SURFACE
A HIGH PRESSURE WAS PROGRESSING OUT OF THE TRI-AREA AHEAD OF THE
PRE-FRONTAL TROUGH THAT WILL MOVE THROUGH TODAY.
JTL
&&
.SHORT TERM (TODAY-WEDNESDAY)...
227 AM MST MON DEC 26 2011
TEMPERATURES WILL BE THE MAIN FOCUS FOR THIS PERIOD.
TODAY A PRE-FRONTAL SURFACE TROUGH WILL MOVE THROUGH THE AREA DURING
THE DAY...CAUSING THE SOUTHWEST WINDS TO SHIFT TO THE NORTHWEST.
WITH LITTLE MOISTURE TO WORK WITH...AM ONLY ANTICIPATING STRONGER
WINDS AND A FEW CLOUDS BEHIND THE TROUGH. HIGH TEMPERATURES WILL BE
SIMILAR TO YESTERDAY.
TUESDAY THROUGH WEDNESDAY...ANOTHER SURFACE AND UPPER LEVEL TROUGH
WILL MOVE THROUGH THE TRI-STATE AREA DURING THE LATE AFTERNOON AND
EVENING HOURS. SOUNDINGS AND CROSS SECTIONS SHOW UPPER LEVEL
MOISTURE INCREASING AS THE TROUGH MOVES THROUGH. THERE ALSO IS SOME
INSTABILITY PRESENT...ALONG WITH LIFT FROM FRONTOGENESIS AND WARM
AIR ADVECTION AS THE TROUGH MOVES THROUGH. HOWEVER A NARROW LAYER
OF MUCH DRIER AIR BETWEEN THE SURFACE AND THE MOISTURE MAY HINDER
ANY PRECIPITATION FROM REACHING THE GROUND. CANNOT COMPLETELY RULE
OUT SOMETHING FROM REACHING THE GROUND SO WILL ADD A MENTION OF
FLURRIES FOR AREAS NORTH OF A BENKELMAN TO HILL CITY LINE. TEMPERATURES
WILL BE COOLER TUESDAY AS SLIGHTLY COOLER AIR WILL MOVE IN BEHIND
MONDAY/S TROUGH. WEDNESDAY THE ENVIRONMENT DRIES OUT BEHIND THE
TROUGH. TEMPERATURES WILL BE WARMER AS 850MB TEMPERATURES
INCREASE.
JTL
.LONG TERM (THURSDAY-SUNDAY)...
227 AM MST MON DEC 26 2011
A SERIES OF WEAK SHORT WAVE TROUGHS WILL MOVE ACROSS
THE HIGH PLAINS THROUGH THE REST OF THE WEEK...BUT BEST LIFT AND
MOISTURE WILL BE FAR NORTH OF THE FORECAST AREA. MODELS INDICATE THE
BEST CHANCE FOR ANY PRECIPITATION WOULD BE TOWARD THE END OF THE
PERIOD...SATURDAY NIGHT/SUNDAY MORNING. MODELS DIFFER IN THEIR
SOLUTIONS AT THAT TIME. THE ECMWF IS FURTHER SOUTH AND WEST WITH
DYNAMICS AND MOISTURE THAN THE GFS. WITH ENSEMBLES SHOWING WIDE
VARIABILITY AFTER 120 HOURS...WILL STAY THE COURSE OF A DRY
FORECAST. TEMPERATURES WILL BE ABOVE NORMAL WITH DAILY MAXIMUM
TEMPERATURES MAINLY IN THE 50S.
&&
.AVIATION...
1013 AM MST MON DEC 26 2011
FOR THE 18Z TAFS...VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD
AT BOTH TERMINALS. A COLD FRONT WILL MOVE THROUGH THE TERMINALS
DURING THE FIRST HOUR OF THE PERIOD...CAUSING WINDS TO SHIFT TO
THE NORTHWEST AND BECOME STRONGER. BEHIND THE FRONT...WINDS WILL
INCREASE FURTHER AND VEER SLIGHTLY MORE. WINDS WILL DECREASE NEAR
00Z AS DAYTIME MIXING ENDS.
CJS
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS DODGE CITY KS
1042 AM CST MON DEC 26 2011
.AVIATION...
FOR THE 18Z TAF ISSUANCE...
A NORTHERN BRANCH SHORTWAVE TROUGH WILL MOVE ACROSS THE NORTHERN
HIGH PLAINS AND INTO THE UPPER MIDWEST BY 12Z TUES. THIS SYSTEM
WILL PUSH A DRY COLD FRONT ACROSS WESTERN KANSAS THIS EVENING.
WINDS WILL SHIFT FROM THE SOUTHWEST TO THE NORTHWEST AT 10 TO
15 KTS BY 00Z AT KDDC, AND AROUND 23Z AT KHYS AND KGCK. VFR
CONDITIONS ARE EXPECTED WITH ONLY SOME SCT HIGH LEVEL CIRRUS.
&&
PREV DISCUSSION... /ISSUED 222 AM CST MON DEC 26 2011/
SYNOPSIS...
MID AND UPPER AIR ANALYSIS INDICATES A SHORTWAVE TROUGH PUSHING ACROSS
MONTANA. A 500 HPA LOW WAS SPINNING ACROSS THE WESTERN TEXAS PANHANDLE.
MOISTURE ADVECTION WAS EVIDENT ON THE KDDC RAOB AS THE MIDDLE ATMOSPHERE
MOISTENED UP CONSIDERABLY IN THE 12 HOUR GAP BETWEEN SYNOPTIC FLIGHTS.
KDDC WSR-88D WAS DETECTING SOME LIGHT ECHOES ACROSS SOUTH CENTRAL KANSAS.
A QUICK CALL MADE TO BARBER COUNTY INDICATES SOME SPRINKLES WERE OCCURRING
WITHIN THE COUNTY. -SUGDEN
DISCUSSION...
DAYS 1-2...
TODAY:
THE IMMEDIATE SHORT TERM CONCERN WAS TO TREND POPS AND WX TO RADAR TRENDS
ACROSS SOUTH CENTRAL KANSAS. THIS ACTIVITY WAS IN RESPONSE TO 600-700
HPA FRONTOGENESIS. HAVE FOLLOWED HRRR GUIDANCE ON THE DEPARTURE OF THIS
ACTIVITY THROUGH THE MORNING. FORECAST SOUNDINGS SHOW A DRY THERMODYNAMIC
PROFILE BELOW 850 HPA SO THINK MOST OF THIS ACTIVITY IS EVAPORATING
BEFORE REACHING THE SURFACE. HAVE KEPT 15 PERCENT POPS IN THE GRIDS
AND WILL QUICKLY TAPER TO ZERO TOWARDS 15Z THIS MORNING. OTHER CONCERN
IS A 5KFT STRATUS LAYER THAT HAS SPREAD ACROSS MUCH OF SOUTHWEST KANSAS.
THINK THIS WILL MOVE OFF TO THE EAST AND REDUCE IN AERIAL COVERAGE WITH
MIXING TOWARDS MID MORNING.
MEANWHILE, THE AFOREMENTIONED UPPER LEVEL SHORTWAVE TROUGH MENTIONED
IN THE SYNOPSIS WILL USHER IN A COLD FRONT TONIGHT. PRECIPITATION IS
NOT EXPECTED ALONG THE BOUNDARY AS THE ATMOSPHERE IS FAIRLY DRY AND
DRY AIR ADVECTION WILL CONTINUE IN THE WAKE OF THE SURFACE BOUNDARY.
THE MAIN IMPACTS FROM THE DENSITY GRADIENT WILL BE A SHIFT IN THE WINDS.
HIGHS TODAY WILL BE MAINLY IN THE 30S DEG F FOR MUCH OF THE COUNTY WARNING
AREA EXCEPT TOWARDS SOUTH CENTRAL KANSAS WHERE 40S DEG F ARE FORECAST.
A CONTINUATION OF THE EROSION OF THE SNOWPACK IS EXPECTED TODAY, PARTICULARLY
ACROSS THE EASTERN SECTIONS OF THE SNOWPACK.
TONIGHT:
POST FRONTAL 10 TO 15 KT NORTHWESTERLY TO NORTHERLY WINDS ARE EXPECTED
TONIGHT AND THROUGH THE OVERNIGHT HOURS. MINIMUMS SHOULD BE WARMER HEADING
INTO TUESDAY MORNING AS WINDS CONTINUE IN THE 5 TO 10 KT RANGE OVERNIGHT AND
PROVIDE SLIGHTLY MORE MIXING. TEENS TO UPPER 20 DEG F ARE EXPECTED ACROSS
THE REGION WITH THE COOLEST TEMPERATURES ACROSS MY NORTHWEST COUNTIES.
TUESDAY:
A SURFACE RIDGE OF HIGH PRESSURE WILL SLIDE ACROSS KANSAS TUESDAY.
SOUTHERLY WINDS ARE EXPECTED ON THE BACKSIDE OF THE HIGH BY TUESDAY
EVENING ACROSS WESTERN KANSAS. LOW 50S DEG F TEMPERATURES ARE POSSIBLE
TOWARDS P28 TOMORROW. OTHERWISE MOST OF THE REGION SHOULD BE IN THE
UPPER 30S DEG F (MAINLY ACROSS SNOWPACK) AND 40S DEG F ACROSS BARE GROUND.
THE SNOWPACK WILL CONTINUE TO ERODE THROUGH THE DAY ON TUESDAY.
TUESDAY NIGHT:
I HAVE INCREASED CLOUD COVER TUESDAY EVENING INTO WEDNESDAY MORNING
AS MID TO UPPER LEVEL SATURATION IS INDICATED BY FORECAST SOUNDINGS
AHEAD OF A SECONDARY APPROACHING SHORTWAVE TROUGH MOVING ACROSS THE
PLAINS. MODELS ARE NOT INDICATING ANY QPF WITH THIS SYSTEM SO STILL
HAVE POPS AT ZERO THROUGH THE EVENING. FORECAST SOUNDINGS ALSO SHOW
A DRY PROFILE BELOW 700 HPA WHICH SUPPORTS A DRY FORECAST. -SUGDEN
DAYS 3-7...
THE MEDIUM RANGE FORECAST CONTINUES TO LOOK WARM AND DRY IN A PROLONGED
DOWNSLOPE-FAVORED UPPER AIR PATTERN...WITH NO HAZARDOUS WINTER WEATHER
EXPECTED FOR MUCH OF THE WESTERN PLAINS. THAT BEING SAID...WILL BE WATCHING
FOR POSSIBLE STORM DEVELOPMENT EAST OF HERE AROUND THE 1ST OF JANUARY
AS THE LARGE SCALE CIRCULATION REGIME AMPLIFIES.
WEDNESDAY-FRIDAY:
WEST-NORTHWESTERLY DOWNSLOPE MOMENTUM WILL YIELD A WARMING LOWER TROPOSPHERE
AND DAILY TEMPERATURES WARMING INTO THE 50S. WHATEVER SNOWPACK REMAINS
BY WEDNESDAY WILL BE TAKING A SERIOUS HIT DURING THIS TIME FRAME WITH
ALMOST NO INFLUENCE AT ALL OF SNOWPACK ON TEMPERATURES BY THE END OF
THE WEEK AS MUCH OF IT SHOULD BE MELTED BY THEN (EXCEPT FOR THE COLORADO
BORDER AREAS). HIGHS IN THE MID 50S ARE LIKELY AND PERHAPS A FEW 60
DEGREE READINGS WILL OCCUR ACROSS SOUTH-CENTRAL KANSAS ZONES THURSDAY
AND FRIDAY.
SATURDAY-SUNDAY:
A LARGE RIDGE IS EXPECTED TO FORM ALONG THE WEST COAST/WESTERN CONUS
WHICH WILL FAVOR A DOWNSTREAM TROUGH DEVELOPMENT OVER THE CENTRAL/EASTERN
PLAINS. THE FORMATION OF THIS TROUGH IS SHOWN BY ALL THE GLOBAL MODELS
TO BE OVER OR EAST OF WESTERN KANSAS WHICH DOES NOT FAVOR WIDESPREAD
ACCUMULATING PRECIPITATION GIVEN UNFAVORABLE LOW LEVEL TRAJECTORIES
TO OUR SOUTH (MOISTURE ADVECTION). A MID LATITUDE CYCLONE OF SOME SEMBLANCE
WILL PROBABLY MATURE OVER THE MIDWEST /OHIO-VALLEY AS A RESULT OF THIS
TROUGH DEVELOPMENT WITH STRONG, DRY NORTHWEST WINDS ACROSS THE WESTERN
PLAINS ON THE ORDER OF LATE SATURDAY INTO SUNDAY. SINCE THIS IS STILL
IN THE DAY 6-7 TIME RANGE THERE IS STILL SOME UNCERTAINTY AS TO WHEN/WHERE
(OR EVEN IF) EXACTLY A STORM WILL FORM SO WILL HAVE TO WATCH SUBSEQUENT
MODEL SOLUTIONS TO SEE HOW THIS TROUGH DEVELOPS AND IF IT WILL HAVE
ANY SUBSTANTIAL SENSIBLE WEATHER IMPACTS ON SOUTHWEST KANSAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 36 21 42 23 / 0 0 0 0
GCK 33 17 37 19 / 0 0 0 0
EHA 35 21 43 25 / 0 0 0 0
LBL 36 19 45 22 / 0 0 0 0
HYS 37 23 41 25 / 0 0 0 0
P28 44 26 50 26 / 10 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
FN06/99/99
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
618 AM CST MON DEC 26 2011
.AVIATION...
FOR THE 12Z TAF ISSUANCE...
DESPITE THE SCATTERED SPRINKLES AND VERY LIGHT SNOW ACROSS
PORTIONS OF SOUTHWEST/SOUTH CENTRAL KANSAS EARLY THIS
MORNING...FLIGHT CATEGORY HAS REMAINED VFR. THE UPPER LOW WILL BE
MOVING AWAY FROM THE REGION TODAY AND SO WILL THE LOW TO MID LEVEL
STRATUS CLOUD COVER. WINDS WILL INCREASE BY LATE THIS
AFTERNOON/EARLY THIS EVENING AS A SURFACE TROUGH MOVES EAST ACROSS
WESTERN KANSAS. NORTHWEST WINDS THIS EVENING SHOULD BE ABOVE 12
KNOTS WITH HIGHER GUSTS 00Z TO 06Z BEHIND THE FRONT.
&&
.PREV DISCUSSION... /ISSUED 222 AM CST MON DEC 26 2011/
SYNOPSIS...
MID AND UPPER AIR ANALYSIS INDICATES A SHORTWAVE TROUGH PUSHING ACROSS
MONTANA. A 500 HPA LOW WAS SPINNING ACROSS THE WESTERN TEXAS PANHANDLE.
MOISTURE ADVECTION WAS EVIDENT ON THE KDDC RAOB AS THE MIDDLE ATMOSPHERE
MOISTENED UP CONSIDERABLY IN THE 12 HOUR GAP BETWEEN SYNOPTIC FLIGHTS.
KDDC WSR-88D WAS DETECTING SOME LIGHT ECHOES ACROSS SOUTH CENTRAL KANSAS.
A QUICK CALL MADE TO BARBER COUNTY INDICATES SOME SPRINKLES WERE OCCURRING
WITHIN THE COUNTY. -SUGDEN
DISCUSSION...
DAYS 1-2...
TODAY:
THE IMMEDIATE SHORT TERM CONCERN WAS TO TREND POPS AND WX TO RADAR TRENDS
ACROSS SOUTH CENTRAL KANSAS. THIS ACTIVITY WAS IN RESPONSE TO 600-700
HPA FRONTOGENESIS. HAVE FOLLOWED HRRR GUIDANCE ON THE DEPARTURE OF THIS
ACTIVITY THROUGH THE MORNING. FORECAST SOUNDINGS SHOW A DRY THERMODYNAMIC
PROFILE BELOW 850 HPA SO THINK MOST OF THIS ACTIVITY IS EVAPORATING
BEFORE REACHING THE SURFACE. HAVE KEPT 15 PERCENT POPS IN THE GRIDS
AND WILL QUICKLY TAPER TO ZERO TOWARDS 15Z THIS MORNING. OTHER CONCERN
IS A 5KFT STRATUS LAYER THAT HAS SPREAD ACROSS MUCH OF SOUTHWEST KANSAS.
THINK THIS WILL MOVE OFF TO THE EAST AND REDUCE IN AERIAL COVERAGE WITH
MIXING TOWARDS MID MORNING.
MEANWHILE, THE AFOREMENTIONED UPPER LEVEL SHORTWAVE TROUGH MENTIONED
IN THE SYNOPSIS WILL USHER IN A COLD FRONT TONIGHT. PRECIPITATION IS
NOT EXPECTED ALONG THE BOUNDARY AS THE ATMOSPHERE IS FAIRLY DRY AND
DRY AIR ADVECTION WILL CONTINUE IN THE WAKE OF THE SURFACE BOUNDARY.
THE MAIN IMPACTS FROM THE DENSITY GRADIENT WILL BE A SHIFT IN THE WINDS.
HIGHS TODAY WILL BE MAINLY IN THE 30S DEG F FOR MUCH OF THE COUNTY WARNING
AREA EXCEPT TOWARDS SOUTH CENTRAL KANSAS WHERE 40S DEG F ARE FORECAST.
A CONTINUATION OF THE EROSION OF THE SNOWPACK IS EXPECTED TODAY, PARTICULARLY
ACROSS THE EASTERN SECTIONS OF THE SNOWPACK.
TONIGHT:
POST FRONTAL 10 TO 15 KT NORTHWESTERLY TO NORTHERLY WINDS ARE EXPECTED
TONIGHT AND THROUGH THE OVERNIGHT HOURS. MINIMUMS SHOULD BE WARMER HEADING
INTO TUESDAY MORNING AS WINDS CONTINUE IN THE 5 TO 10 KT RANGE OVERNIGHT AND
PROVIDE SLIGHTLY MORE MIXING. TEENS TO UPPER 20 DEG F ARE EXPECTED ACROSS
THE REGION WITH THE COOLEST TEMPERATURES ACROSS MY NORTHWEST COUNTIES.
TUESDAY:
A SURFACE RIDGE OF HIGH PRESSURE WILL SLIDE ACROSS KANSAS TUESDAY.
SOUTHERLY WINDS ARE EXPECTED ON THE BACKSIDE OF THE HIGH BY TUESDAY
EVENING ACROSS WESTERN KANSAS. LOW 50S DEG F TEMPERATURES ARE POSSIBLE
TOWARDS P28 TOMORROW. OTHERWISE MOST OF THE REGION SHOULD BE IN THE
UPPER 30S DEG F (MAINLY ACROSS SNOWPACK) AND 40S DEG F ACROSS BARE GROUND.
THE SNOWPACK WILL CONTINUE TO ERODE THROUGH THE DAY ON TUESDAY.
TUESDAY NIGHT:
I HAVE INCREASED CLOUD COVER TUESDAY EVENING INTO WEDNESDAY MORNING
AS MID TO UPPER LEVEL SATURATION IS INDICATED BY FORECAST SOUNDINGS
AHEAD OF A SECONDARY APPROACHING SHORTWAVE TROUGH MOVING ACROSS THE
PLAINS. MODELS ARE NOT INDICATING ANY QPF WITH THIS SYSTEM SO STILL
HAVE POPS AT ZERO THROUGH THE EVENING. FORECAST SOUNDINGS ALSO SHOW
A DRY PROFILE BELOW 700 HPA WHICH SUPPORTS A DRY FORECAST. -SUGDEN
DAYS 3-7...
THE MEDIUM RANGE FORECAST CONTINUES TO LOOK WARM AND DRY IN A PROLONGED
DOWNSLOPE-FAVORED UPPER AIR PATTERN...WITH NO HAZARDOUS WINTER WEATHER
EXPECTED FOR MUCH OF THE WESTERN PLAINS. THAT BEING SAID...WILL BE WATCHING
FOR POSSIBLE STORM DEVELOPMENT EAST OF HERE AROUND THE 1ST OF JANUARY
AS THE LARGE SCALE CIRCULATION REGIME AMPLIFIES.
WEDNESDAY-FRIDAY:
WEST-NORTHWESTERLY DOWNSLOPE MOMENTUM WILL YIELD A WARMING LOWER TROPOSPHERE
AND DAILY TEMPERATURES WARMING INTO THE 50S. WHATEVER SNOWPACK REMAINS
BY WEDNESDAY WILL BE TAKING A SERIOUS HIT DURING THIS TIME FRAME WITH
ALMOST NO INFLUENCE AT ALL OF SNOWPACK ON TEMPERATURES BY THE END OF
THE WEEK AS MUCH OF IT SHOULD BE MELTED BY THEN (EXCEPT FOR THE COLORADO
BORDER AREAS). HIGHS IN THE MID 50S ARE LIKELY AND PERHAPS A FEW 60
DEGREE READINGS WILL OCCUR ACROSS SOUTH-CENTRAL KANSAS ZONES THURSDAY
AND FRIDAY.
SATURDAY-SUNDAY:
A LARGE RIDGE IS EXPECTED TO FORM ALONG THE WEST COAST/WESTERN CONUS
WHICH WILL FAVOR A DOWNSTREAM TROUGH DEVELOPMENT OVER THE CENTRAL/EASTERN
PLAINS. THE FORMATION OF THIS TROUGH IS SHOWN BY ALL THE GLOBAL MODELS
TO BE OVER OR EAST OF WESTERN KANSAS WHICH DOES NOT FAVOR WIDESPREAD
ACCUMULATING PRECIPITATION GIVEN UNFAVORABLE LOW LEVEL TRAJECTORIES
TO OUR SOUTH (MOISTURE ADVECTION). A MID LATITUDE CYCLONE OF SOME SEMBLANCE
WILL PROBABLY MATURE OVER THE MIDWEST /OHIO-VALLEY AS A RESULT OF THIS
TROUGH DEVELOPMENT WITH STRONG, DRY NORTHWEST WINDS ACROSS THE WESTERN
PLAINS ON THE ORDER OF LATE SATURDAY INTO SUNDAY. SINCE THIS IS STILL
IN THE DAY 6-7 TIME RANGE THERE IS STILL SOME UNCERTAINTY AS TO WHEN/WHERE
(OR EVEN IF) EXACTLY A STORM WILL FORM SO WILL HAVE TO WATCH SUBSEQUENT
MODEL SOLUTIONS TO SEE HOW THIS TROUGH DEVELOPS AND IF IT WILL HAVE
ANY SUBSTANTIAL SENSIBLE WEATHER IMPACTS ON SOUTHWEST KANSAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 36 21 42 23 / 0 0 0 0
GCK 33 17 37 19 / 0 0 0 0
EHA 35 21 43 25 / 0 0 0 0
LBL 36 19 45 22 / 0 0 0 0
HYS 37 23 41 25 / 20 0 0 0
P28 44 26 50 26 / 20 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
FN99/99/25
AREA FORECAST DISCUSSION
NWS GOODLAND KS
358 AM MST MON DEC 26 2011
.SYNOPSIS...
LATEST IR SATELLITE IMAGERY AND RUC ANALYSIS SHOWED A SHORT WAVE
TROUGH MOVING ACROSS THE NORTHERN CONUS WITH AREAS OF CLOUDS AHEAD
OF IT. FURTHER SOUTH THE CLOSED LOW CONTINUES TO SPIN OVER EASTERN
NEW MEXICO AND WESTERN TEXAS. CURRENT RADAR SHOWS ECHOES OVER
SOUTHWEST KANSAS AS SOME MOISTURE MOVES UP FROM THE CLOSED LOW...WITH
A FEW SPRINKLES AND LIGHT SNOW REACHING THE GROUND. AT THE SURFACE
A HIGH PRESSURE WAS PROGRESSING OUT OF THE TRI-AREA AHEAD OF THE
PRE-FRONTAL TROUGH THAT WILL MOVE THROUGH TODAY.
JTL
&&
.SHORT TERM (TODAY-WEDNESDAY)...
227 AM MST MON DEC 26 2011
TEMPERATURES WILL BE THE MAIN FOCUS FOR THIS PERIOD.
TODAY A PRE-FRONTAL SURFACE TROUGH WILL MOVE THROUGH THE AREA DURING
THE DAY...CAUSING THE SOUTHWEST WINDS TO SHIFT TO THE NORTHWEST.
WITH LITTLE MOISTURE TO WORK WITH...AM ONLY ANTICIPATING STRONGER
WINDS AND A FEW CLOUDS BEHIND THE TROUGH. HIGH TEMPERATURES WILL BE
SIMILAR TO YESTERDAY.
TUESDAY THROUGH WEDNESDAY...ANOTHER SURFACE AND UPPER LEVEL TROUGH
WILL MOVE THROUGH THE TRI-STATE AREA DURING THE LATE AFTERNOON AND
EVENING HOURS. SOUNDINGS AND CROSS SECTIONS SHOW UPPER LEVEL
MOISTURE INCREASING AS THE TROUGH MOVES THROUGH. THERE ALSO IS SOME
INSTABILITY PRESENT...ALONG WITH LIFT FROM FRONTOGENESIS AND WARM
AIR ADVECTION AS THE TROUGH MOVES THROUGH. HOWEVER A NARROW LAYER
OF MUCH DRIER AIR BETWEEN THE SURFACE AND THE MOISTURE MAY HINDER
ANY PRECIPITATION FROM REACHING THE GROUND. CANNOT COMPLETELY RULE
OUT SOMETHING FROM REACHING THE GROUND SO WILL ADD A MENTION OF
FLURRIES FOR AREAS NORTH OF A BENKELMAN TO HILL CITY LINE. TEMPERATURES
WILL BE COOLER TUESDAY AS SLIGHTLY COOLER AIR WILL MOVE IN BEHIND
MONDAY/S TROUGH. WEDNESDAY THE ENVIRONMENT DRIES OUT BEHIND THE
TROUGH. TEMPERATURES WILL BE WARMER AS 850MB TEMPERATURES
INCREASE.
JTL
.LONG TERM (THURSDAY-SUNDAY)...
227 AM MST MON DEC 26 2011
A SERIES OF WEAK SHORT WAVE TROUGHS WILL MOVE ACROSS
THE HIGH PLAINS THROUGH THE REST OF THE WEEK...BUT BEST LIFT AND
MOISTURE WILL BE FAR NORTH OF THE FORECAST AREA. MODELS INDICATE THE
BEST CHANCE FOR ANY PRECIPITATION WOULD BE TOWARD THE END OF THE
PERIOD...SATURDAY NIGHT/SUNDAY MORNING. MODELS DIFFER IN THEIR
SOLUTIONS AT THAT TIME. THE ECMWF IS FURTHER SOUTH AND WEST WITH
DYNAMICS AND MOISTURE THAN THE GFS. WITH ENSEMBLES SHOWING WIDE
VARIABILITY AFTER 120 HOURS...WILL STAY THE COURSE OF A DRY
FORECAST. TEMPERATURES WILL BE ABOVE NORMAL WITH DAILY MAXIMUM
TEMPERATURES MAINLY IN THE 50S.
&&
.AVIATION...
358 AM MST MON DEC 26 2011
VFR CONDITIONS WILL CONTINUE AT KGLD/KMCK. A WEAK COLD FRONT WILL
MOVE ACROSS BOTH SITES AROUND 18Z SWITCHING SURFACE WINDS TO THE
NORTHWEST AND PRODUCING GUSTS TO 25 KNOTS THROUGH THE AFTERNOON.
OTHERWISE...ONLY CIRRUS IS EXPECTED.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1211 AM EST WED DEC 28 2011
...Updated Aviation Discussion...
.Forecast Update...
Snowfall earlier today occurred across all of the South Indiana
counties, with most counties in north central Kentucky also seeing
traces. The only accumulations noted in our forecast area were in
Dubois, Orange, Crawford, and Washington counties, where at most a
half inch accumulated on grassy and elevated surfaces. That snow
now has melted.
The expected follow-up precipitation has taken a little longer than
expected to develop, much later than the HRRR indicated but in line
with the 12Z SPC WRF. The latter model pointed more to the upslope
causing snows over the eastern forecast area, and latest 88D is now
showing some indication that a drizzle/flurry mix is developing in
this region. Based on dry air driving its way into the region, this
precipitation will not last more than a few more hours.
Likely will continue to issue the special weather statement about
some slick spots on area roads overnight. Winds this afternoon and
evening have done a good job of drying out area roadways according
to road webcams. Still expect a few patches to have been wind
protected, and with temperatures falling into the upper 20s, these
patches should freeze over.
&&
.Short Term (This Evening - Wednesday)...
Precipitation has all but ended across the CWA with barely
measurable rain or light snow moving east of I 65 and into the
Bluegrass. Several calls were made to southern Indiana and west
central Kentucky counties late this morning/early this afternoon
with most locations only picking up traces of snowfall. The most
noticeable accumulations were in Dubois county where up to a half
inch accumulated on grassy surfaces and cars.
Also of note, the all time precipitation record for a year was
broken at Lexington today. As of 7 AM EST this morning, total
rainfall for the year at Lexington was 65.86 inches which surpassed
the old record of 65.76 inches set back in 1935. Additional rainfall
amounts of around a half an inch fell after 7 AM and will be tallied
after precipitation ends later this evening.
Surface low has moved off to the northeast and is on its way to the
eastern Great Lakes this evening. Surface winds will continue to be
strong as pressure gradient is tight behind the deepening low. Look
for west northwest winds between 10 and 20 mph, gusting as high as
30 mph through about 7 PM EST. Thereafter, winds will gradually
slacken to the 5 to 15 mph range overnight.
Looking upstream across west central Indiana and southern Illinois,
temperatures have warmed back into the upper 30s and lower 40s. Raw
Nam surface temperatures had this depicted well so have used them
for the temperature trend through this evening. Temperatures will
remain steady or warm slightly to the upper 30s before gradually
falling after midnight to the upper 20s and around 30 degrees. Will
have to watch a secondary surge of low level moisture streaming into
the area from the northwest as this could produce flurries or a
light snow shower with west northwest flow aiding in some upslope
lift. Also, a look at forecast soundings actually shows some
convective instability in the lowest levels, although saturation
only makes it to about -8 C before low level moisture is cut off.
Given the fact that ice crystals may be hard to come by and low
level moisture is shallow, will only include flurries along and west
of I 65 late this afternoon and this evening. Best chance for a
light snow shower will be in the Bluegrass. Will let SPS that had
voiced concern about scattered moderate snow showers and re-freezing
of roadways overnight expire at 5 PM EST.
Otherwise, precipitation threat exits the Bluegrass region shortly
after midnight with dry weather and mostly clear to partly cloudy
skies through Wednesday. The west northwest wind will continue on
Wednesday and only allow highs to get into the upper 30s to around
40 degrees.
.Long Term (Wednesday Night - Tuesday)...
The first weather system of interest in the long term period is a
clipper system diving down from the NW for Thurs night/Fri. This
system should bring light rain to portions of southern Indiana and
north central KY including the Bluegrass. Ahead of this system,
temperatures will warm into the upper 40s and lower 50s for highs on
Thurs. Lows should range from the upper 20s/lower 30s Wed night to
upper 30s/lower 40s for Thurs night.
We`ll see a brief break in weather systems Friday Night/Saturday
before the pattern reloads. There is very low confidence in the
weekend weather system. The 12Z ECMWF overly deepens a significant
trough over the Plains states by early next week while the 12Z GFS
depicts a much shallower progressive trough. Think that the real
soln is some where in the middle so tried to reflect that in the
grids. Will keep low 20-30% POPs Sat night-Sun night until a
reasonable consensus can be reached. Seems like the 12Z GFS trended
deeper with its trough, however, the 12Z ECMWF looks like it fell
off the deep end with digging such a deep trough over the CONUS.
The degree of troughing will determine temperatures and weather
type. Right now will put highs in the 50s ahead of it and 30s and
40s behind it.
&&
.Aviation (06Z TAF Issuance)...
Back edge of clouds associated with an exiting upper trough/lake
effect enhancement will soon move across the terminals and SDF and
LEX will improve to VFR (BWG will remain VFR). Through the next few
hours though, roughly by 09z, CIGs at SDF/LEX will be in the MVFR
range with even a small chance for very light snow/drizzle mix at
LEX. Gusty winds may occur, as well, over the next few hours.
By or shortly after 12z, high pressure will spread across the
region, helping to relax our gusty northwest winds as they back
around to the west-southwest. A weak upper level wave will bring in
mid-upper level clouds nearly as soon as the strato-cu deck exits
this morning. However, VFR conditions will be the rule from
mid-morning on.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........RJS
Short Term.......BJS
Long Term........AMS
Aviation.........AL
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
905 PM EST TUE DEC 27 2011
...Forecast Update...
Snowfall earlier today occurred across all of the South Indiana
counties, with most counties in north central Kentucky also seeing
traces. The only accumulations noted in our forecast area were in
Dubois, Orange, Crawford, and Washington counties, where at most a
half inch accumulated on grassy and elevated surfaces. That snow
now has melted.
The expected follow-up precipitation has taken a little longer than
expected to develop, much later than the HRRR indicated but in line
with the 12Z SPC WRF. The latter model pointed more to the upslope
causing snows over the eastern forecast area, and latest 88D is now
showing some indication that a drizzle/flurry mix is developing in
this region. Based on dry air driving its way into the region, this
precipitation will not last more than a few more hours.
Likely will continue to issue the special weather statement about
some slick spots on area roads overnight. Winds this afternoon and
evening have done a good job of drying out area roadways according
to road webcams. Still expect a few patches to have been wind
protected, and with temperatures falling into the upper 20s, these
patches should freeze over.
&&
.Short Term (This Evening - Wednesday)...
Precipitation has all but ended across the CWA with barely
measurable rain or light snow moving east of I 65 and into the
Bluegrass. Several calls were made to southern Indiana and west
central Kentucky counties late this morning/early this afternoon
with most locations only picking up traces of snowfall. The most
noticeable accumulations were in Dubois county where up to a half
inch accumulated on grassy surfaces and cars.
Also of note, the all time precipitation record for a year was
broken at Lexington today. As of 7 AM EST this morning, total
rainfall for the year at Lexington was 65.86 inches which surpassed
the old record of 65.76 inches set back in 1935. Additional rainfall
amounts of around a half an inch fell after 7 AM and will be tallied
after precipitation ends later this evening.
Surface low has moved off to the northeast and is on its way to the
eastern Great Lakes this evening. Surface winds will continue to be
strong as pressure gradient is tight behind the deepening low. Look
for west northwest winds between 10 and 20 mph, gusting as high as
30 mph through about 7 PM EST. Thereafter, winds will gradually
slacken to the 5 to 15 mph range overnight.
Looking upstream across west central Indiana and southern Illinois,
temperatures have warmed back into the upper 30s and lower 40s. Raw
Nam surface temperatures had this depicted well so have used them
for the temperature trend through this evening. Temperatures will
remain steady or warm slightly to the upper 30s before gradually
falling after midnight to the upper 20s and around 30 degrees. Will
have to watch a secondary surge of low level moisture streaming into
the area from the northwest as this could produce flurries or a
light snow shower with west northwest flow aiding in some upslope
lift. Also, a look at forecast soundings actually shows some
convective instability in the lowest levels, although saturation
only makes it to about -8 C before low level moisture is cut off.
Given the fact that ice crystals may be hard to come by and low
level moisture is shallow, will only include flurries along and west
of I 65 late this afternoon and this evening. Best chance for a
light snow shower will be in the Bluegrass. Will let SPS that had
voiced concern about scattered moderate snow showers and re-freezing
of roadways overnight expire at 5 PM EST.
Otherwise, precipitation threat exits the Bluegrass region shortly
after midnight with dry weather and mostly clear to partly cloudy
skies through Wednesday. The west northwest wind will continue on
Wednesday and only allow highs to get into the upper 30s to around
40 degrees.
.Long Term (Wednesday Night - Tuesday)...
The first weather system of interest in the long term period is a
clipper system diving down from the NW for Thurs night/Fri. This
system should bring light rain to portions of southern Indiana and
north central KY including the Bluegrass. Ahead of this system,
temperatures will warm into the upper 40s and lower 50s for highs on
Thurs. Lows should range from the upper 20s/lower 30s Wed night to
upper 30s/lower 40s for Thurs night.
We`ll see a brief break in weather systems Friday Night/Saturday
before the pattern reloads. There is very low confidence in the
weekend weather system. The 12Z ECMWF overly deepens a significant
trough over the Plains states by early next week while the 12Z GFS
depicts a much shallower progressive trough. Think that the real
soln is some where in the middle so tried to reflect that in the
grids. Will keep low 20-30% POPs Sat night-Sun night until a
reasonable consensus can be reached. Seems like the 12Z GFS trended
deeper with its trough, however, the 12Z ECMWF looks like it fell
off the deep end with digging such a deep trough over the CONUS.
The degree of troughing will determine temperatures and weather
type. Right now will put highs in the 50s ahead of it and 30s and
40s behind it.
&&
.Aviation (00Z TAF Issuance)...
Scattered showers will develop across the region this evening as an
upper level impulse rotates around the main system now over Lake
Erie. The precip type for KBWG the next few hours should remain as
rain as that area had some warming with the remainder of the
afternoon heating. For KSDF some warming has occurred, so any
development could bring a mixture over the next few hours. KLEX
likely would stay closer to freezing for just snow showers. Model
time-height sections pick up on the upslope over eastern KY bringing
a better chance for snow showers in the east this evening, so have
put in explicitly with a tempo group for MVFR vsby`s but continuing
IFR cigs. Expect conditions to improve there around midnight, with
all sites VFR by then or soon after. Winds will continue from the
west this evening and then subtly shift to west southwesterly around
daybreak Wednesday as high pressure builds into the Deep South.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........RJS
Short Term.......BJS
Long Term........AMS
Aviation.........RJS
AREA FORECAST DISCUSSION
NWS GRAY ME
1141 PM EST TUE DEC 27 2011
.SYNOPSIS...
LOW PRESSURE WILL MOVE NORTHEAST THROUGH EASTERN NEW YORK AND INTO
SOUTHERN QUEBEC OVERNIGHT. A STRONG NORTHWEST FLOW WILL SET UP
BEHIND THE DEPARTING LOW ON WEDNESDAY. WEAK HIGH PRESSURE WILL
BUILD IN FROM THE WEST ON THURSDAY. A WARM FRONT WILL APPROACH
FROM THE SOUTHWEST THURSDAY NIGHT AND STALL OVER THE REGION ON
FRIDAY AS SEVERAL WEAK AREAS OF LOW PRESSURE MOVE EAST ALONG IT.
THE LAST AREA OF LOW PRESSURE WILL CROSS SOUTHERN NEW ENGLAND ON
SATURDAY. A WEAK AREA OF HIGH PRESSURE WILL BUILD OVER THE AREA
SATURDAY NIGHT AND WILL SHIFT OFFSHORE ON SUNDAY AS A WARM FRONT
MOVES IN FROM THE SOUTHWEST. LOW PRESSURE WILL MOVE EAST THROUGH
NORTHERN NEW ENGLAND SUNDAY NIGHT AND INTO THE MARITIMES ON
MONDAY.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
UPDATE...MID LEVEL WARM AIR HAS NOW PUSHED TO THE CANADIAN BORDER...
AND THE SURFACE WARM FRONT HAS PUSHED INLAND ACROSS NORTHERN NEW
ENGLAND. STILL SOME AREAS IN THE FOOTHILLS THAT HAVE NOT SEEN THE
SWITCH TO SOUTHEAST WINDS AND DRAMATICALLY WARMING TEMPERATURES YET.
FRYEBURG... PLYMOUTH... AND LEBANON ARE STILL IN THE MID 30S WITH A
LIGHT NORTH WIND. NORTH OF THE MOUNTAINS... THE SOUTHEAST WINDS
ALOFT HAVE A DOWNSLOPING COMPONENT TO PUSH THE COLD SURFACE AIR OUT
SOONER... HELPING WHITEFIELD AND BERLIN CLIMB INTO THE 40S WITH A
GUSTY SOUTHEAST WIND. EXPECT RAIN FROM HERE ON OUT. DRY SLOT ALOFT
IS PUSHING ACROSS THE AREA... LEADING TO A MORE SHOWERY CONVECTIVE
NATURE TO THE RAIN. SURFACE TROUGH AXIS IS MOVING INTO VERMONT AND
MASSACHUSETTS... BRINGING AN END TO THE PRECIPITATION AS IT MOVES
THROUGH. HAVE UPDATED THE POPS AND TEMPERATURE GRIDS TO REFLECT
CURRENT THINKING REGARDING TIMING OF PRECIPITATION AND WARM AIR.
UPDATE...
TEMPERATURES ARE NOW TAKING OFF AND HAVE ADJUSTED THE GRIDS TO
REFLECT A NON-DIURNAL CURVE WITH THE MIN TEMPERATURE FIELD. THIS
RAPID WARMING IN THE COLUMN THIS EVENING HAS ALLOWED THE MIXED
PCPN TO SWITCH OVER TO MAINLY RAIN. THEREFORE...HAVE ALLOWED THE
FREEZING RAIN ADVISORIES TO EXPIRE. HAVE MENTIONED THIS CHANGEOVER
IN THE HWO AND CONTINUED THE POSSIBILITY OF "PATCHY" FREEZING RAIN
IN THE COLDEST OF THE VALLEYS IN THE MOUNTAINS/FOOTHILLS THROUGH
MIDNIGHT.
THE RAPID WARMING HAS ALSO ALLOWED FOR INCREASED MIXING AND HIGHER
WIND GUSTS THIS LAST HOUR. CONVECTIVE LOOKING RADAR IMAGERY TO OUR
SOUTH WILL QUICKLY MOVE NORTHWARD...BRINGING THE WIND GUSTS UP
SIGNIFICANTLY ALONG THE COAST AND THE HIGHER TERRAIN OVER THE NEXT
ONE TO TWO HOURS.
HAVE ALLOWED FOR THE ENDING OF THE WIND ADVISORIES AROUND 10Z. AT
THAT TIME...THE HRRR EXITS THE BEST PRESSURE GRADIENT OUT OF OUR
FORECAST AREA AND EAST OF PENOBSCOT BAY.
THE REST OF THE GRIDS WILL REMAIN RELATIVELY UNCHANGED. HAVE
NUDGED THE WAVE FORECAST UPWARDS BASED ON THE SWAN GFS
WHICH...DYNAMICALLY MAKES MORE SENSE AND ALSO ALLOWS US TO BE MORE
CONSISTENT WITH OUR CURRENT POSTED MWW.
PREV DISC...
SOME ADJUSTMENTS MADE TO THE GRIDS BASED ON CURRENTS CONDITIONS.
HAVE USED A NON-DIURNAL TEMPERATURE CURVE FOR OVERNIGHT LOWS.
ALSO...HAVE UPPED THE POPS FOR THE FIRST HALF OF THE NIGHT AS PCPN
SHIELD CONTINUES TO QUICKLY MOVE NORTH AND EAST ACROSS THE
FORECAST AREA...DESPITE INITIAL DRY CONDITIONS PER VERY DRY 12Z
GYX SOUNDING. THIS IS ALSO IN GOOD AGREEMENT WITH THE LATEST HRRR
UPDATE THIS HOUR.
THERE MAY CONTINUE TO BE AREAS OF -FZRA EARLY TONIGHT AS BOUNDARY
LAYER TEMPS CONTINUE TO HOVER AROUND FREEZING IN THE NORTHERN
SHELTERED VALLEYS. HAVE ISSUED A FREEZING RAIN ADVISORY UNTIL 10
PM FOR THIS REGION. HAVE ALSO ADDED A CHANCE FOR FREEZING RAIN IN
CENTRAL NH AND THE FOOTHILLS OF MAINE THROUGH THIS EVENING BASED
ON CURRENT AND SHORT TERM FORECAST CONDITIONS.
REST OF GRIDS WILL REMAIN UNCHANGED...HOWEVER...MAY NEED TO TWEAK
WIND GUST GRIDS TO BETTER MATCH CURRENT PRODUCTS.
&&
.SHORT TERM /WEDNESDAY NIGHT/...
COLDER AIR WILL MOVE BACK INTO THE REGION ON WEDNESDAY AS LOW
PRESSURE CONTINUES TO MOVE OFF TO THE NORTHEAST. EXPECT ANY
SHOWERS DOWNWIND OF THE MOUNTAINS TO END DURING THE MORNING HOURS.
IN THE NORTH WILL SEE RAIN SHOWERS CHANGING TO SNOW SHOWERS IN THE
MOUNTAINS WITH SOME MINOR ACCUMULATIONS POSSIBLE. EXPECT STEADY OR
SLOWLY FALLING TEMPERATURES DURING THE DAY WITH MOST AREAS DIPPING
TO THE FREEZING MARK BY LATE AFTERNOON. EXPECT NORTHWEST WINDS TO
INCREASE SIGNIFICANTLY DURING THE AFTERNOON...POSSIBLY REACHING
ADVISORY LEVELS.
WINDY AND VERY COLD WEDNESDAY NIGHT WITH A CONTINUING CHANCE OF
SNOW SHOWERS IN THE MOUNTAINS. ELSEWHERE SKIES WILL GRADUALLY
CLEAR. EXPECT LOWS OF ZERO TO 5 BELOW IN THE NORTH AND IN THE
LOWER TO MID TEENS IN THE SOUTH.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
UPR LVL CUTOFF OVER THE MARITIMES WITH ASSOCIATED DEEP SFC CYCLONE
WILL SLOWLY LIFT NE ON THURSDAY ALLOWING A MORE UPR LVL ZONAL FLOW
TO SET UP WITH AN EMBEDDED VORTICITY MAX/JET SEGMENT TO MOVE TOWARD
THE NE. THIS BRINGS A WEAK SFC LOW AND LEADING WRM FNT TOWARD NEW
ENGLAND. THESE FEATURES CROSS NEW ENGLAND THURSDAY NGT CREATING
CLOUDS AND SOME -SN. ON FRIDAY A SECOND UPR LVL VORTICITY MAX/JET
SEGMENT IN THE WESTERLY FLOW ALOFT MOVES THRU WITH ANOTHER WEAK SFC
LOW AND ROUND OF SOME -SN.
THIS IS FOLLOWED BY A STRONG UPR LVL SHORT WAVE/VORTICITY MAX ON
SATURDAY. THIS FORMS A SFC LOW ALONG THE MID ATLANTIC COAST THAT
STRENGTHENS AS IT MOVES EAST INTO THE ATLANTIC. THE CURRENT TRACK IS
TOO FAR S TO PROVIDE MUCH IN THE WAY OF PRCP FOR THE FCST AREA...
BUT SOME -SN CAN`T BE RULED OUT...ESPECIALLY IF IT ENDS UP TRACKING
A BIT FURTHER N.
AN UPR LVL RIDGE FOLLOWS THE TROF WITH A SFC RIDGE OF HIGH PRES
CROSSING THE REGION SATURDAY NGT PROVIDING FAIR WX. YET ANOTHER UPR
LVL SHORT WAVE MOVES E INTO THE REGION ON SUNDAY. CURRENT MODEL
FORECASTS SHOW THIS AS A STRONG UPR LVL SYSTEM WHICH BRINGS A SFC
LOW E FROM THE UPR GREAT LAKES TOWARD NRN NEW ENGLAND SUNDAY THEN
CROSSES NRN NEW ENGLAND SUNDAY NGT. THE TRACK OF THIS LOW MAY
BRING IN ENOUGH WARM AIR SO THAT PRCP IS NOT CONFINED TO
SN...THERE COULD BE RA OR EVEN MIXED SN/ICE/RA WITH THIS
EVENT...WITH RA MORE LIKELY ALONG THE COAST AND THE N/MT ZONES
MORE LIKELY TO SEE SN. LOTS OF TIME UNTIL THIS EVENT FOR THE TRACK
AND/OR INTENSITY OF THIS SYSTEM TO CHANGE.
THE LOW INTENSIFIES OVER THE MARITIMES ON MONDAY BRINGING IN MUCH
COLDER CANADIAN AIR ON INCREASING AND VERY GUSTY NW WINDS. -SHSN
PSBL ON MONDAY...ESPECIALLY ACROSS THE N/MT ZONES DUE TO OROGRAPHIC
LIFTING UNDER THE UPR LVL CYCLONIC FLOW. THE COLD BLUSTER WX
CONTINUES MONDAY NGT AND TUESDAY.
GENERALLY USED GFS40...HPC QPF AND BLEND OF MAV/MET MOS FOR THURSDAY
AND THURSDAY NGT. USED GMOS FOR REST OF THE LONG TERM FCST...EXCEPT
USED A BLEND OF GFS AND MEX MOS GUIDANCE FOR MAX AND MIN TEMPS.
&&
.AVIATION /04Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM...MVFR/IFR CEILINGS DEVELOPING THIS EVENING...IMPROVING
TO VFR WEDNESDAY MORNING. VFR WEDNESDAY NIGHT WITH AREAS OF MVFR
CEILINGS AND VSBY IN SNOW SHOWERS IN THE NORTH.
LONG TERM /THURSDAY THROUGH SUNDAY/...MVFR TO MAYBE IFR
CONDITIONS PSBL THURSDAY NGT THRU FRIDAY AS A SERIES OF WEAK
SYSTEMS BRING THE POTENTIAL FOR SOME LGT SN. A STRONGER SYSTEM
BRINGS THE CHC FOR SN AND IFR CONDITIONS ON SATURDAY FOLLOWED BY
ANOTHER STRENGTHENING LOW PRES SYSTEM BRINGING A CHC OF MIXED PRCP
AND IFR CONDITIONS ON SUNDAY.
&&
.MARINE...
SHORT TERM...GALE WARNING THROUGH TONIGHT. RAISED SEAS RELYING
HEAVILY ON THE SWAN GFS MODEL.
LONG TERM /THURSDAY THROUGH SUNDAY/...CD NW FLOW ON THURSDAY MAY
RESULT IN CONTINUED GALE FORCE WINDS... AT LEAST THRU THE MORNING.
THE PRES GRADIENT LETS UP LATER IN THE DAY AS WINDS AND SEAS
SUBSIDE. A SERIES OF WEAK LOW PRES SYSTEMS MOVE THRU THURSDAY NGT
AND FRIDAY BUT CONDITIONS LIKELY TO STAY BELOW SCA LEVELS. LOW
PRES PASSES WELL TO THE S ON SATURDAY SO AGAIN CONDITIONS LIKELY
TO REMAIN BELOW SCA THRESHOLDS. A STRONGER LOW PRES SYSTEM MOVES
IN FOR SUNDAY WHICH MAY PRODUCE SCA WINDS AND SEAS.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WIND ADVISORY UNTIL 5 AM EST WEDNESDAY FOR MEZ023>028.
NH...WIND ADVISORY UNTIL 5 AM EST WEDNESDAY FOR NHZ014.
MARINE...GALE WARNING UNTIL 5 AM EST WEDNESDAY FOR ANZ150>154.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAY ME
1037 PM EST TUE DEC 27 2011
.SYNOPSIS...
LOW PRESSURE WILL MOVE NORTHEAST THROUGH EASTERN NEW YORK AND INTO
SOUTHERN QUEBEC OVERNIGHT. A STRONG NORTHWEST FLOW WILL SET UP
BEHIND THE DEPARTING LOW ON WEDNESDAY. WEAK HIGH PRESSURE WILL
BUILD IN FROM THE WEST ON THURSDAY. A WARM FRONT WILL APPROACH
FROM THE SOUTHWEST THURSDAY NIGHT AND STALL OVER THE REGION ON
FRIDAY AS SEVERAL WEAK AREAS OF LOW PRESSURE MOVE EAST ALONG IT.
THE LAST AREA OF LOW PRESSURE WILL CROSS SOUTHERN NEW ENGLAND ON
SATURDAY. A WEAK AREA OF HIGH PRESSURE WILL BUILD OVER THE AREA
SATURDAY NIGHT AND WILL SHIFT OFFSHORE ON SUNDAY AS A WARM FRONT
MOVES IN FROM THE SOUTHWEST. LOW PRESSURE WILL MOVE EAST THROUGH
NORTHERN NEW ENGLAND SUNDAY NIGHT AND INTO THE MARITIMES ON
MONDAY.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
UPDATE...
TEMPERATURES ARE NOW TAKING OFF AND HAVE ADJUSTED THE GRIDS TO
REFLECT A NON-DIURNAL CURVE WITH THE MIN TEMPERATURE FIELD. THIS
RAPID WARMING IN THE COLUMN THIS EVENING HAS ALLOWED THE MIXED
PCPN TO SWITCH OVER TO MAINLY RAIN. THEREFORE...HAVE ALLOWED THE
FREEZING RAIN ADVISORIES TO EXPIRE. HAVE MENTIONED THIS CHANGEOVER
IN THE HWO AND CONTINUED THE POSSIBILITY OF "PATCHY" FREEZING RAIN
IN THE COLDEST OF THE VALLEYS IN THE MOUNTAINS/FOOTHILLS THROUGH MIDNIGHT.
THE RAPID WARMING HAS ALSO ALLOWED FOR INCREASED MIXING AND HIGHER
WIND GUSTS THIS LAST HOUR. CONVECTIVE LOOKING RADAR IMAGERY TO OUR
SOUTH WILL QUICKLY MOVE NORTHWARD...BRINGING THE WIND GUSTS UP
SIGNIFICANTLY ALONG THE COAST AND THE HIGHER TERRAIN OVER THE NEXT
ONE TO TWO HOURS.
HAVE ALLOWED FOR THE ENDING OF THE WIND ADVISORIES AROUND 10Z. AT
THAT TIME...THE HRRR EXITS THE BEST PRESSURE GRADIENT OUT OF OUR
FORECAST AREA AND EAST OF PENOBSCOT BAY.
THE REST OF THE GRIDS WILL REMAIN RELATIVELY UNCHANGED. HAVE
NUDGED THE WAVE FORECAST UPWARDS BASED ON THE SWAN GFS
WHICH...DYNAMICALLY MAKES MORE SENSE AND ALSO ALLOWS US TO BE MORE
CONSISTENT WITH OUR CURRENT POSTED MWW.
PREV DISC...
SOME ADJUSTMENTS MADE TO THE GRIDS BASED ON CURRENTS CONDITIONS.
HAVE USED A NON-DIURNAL TEMPERATURE CURVE FOR OVERNIGHT LOWS.
ALSO...HAVE UPPED THE POPS FOR THE FIRST HALF OF THE NIGHT AS PCPN
SHIELD CONTINUES TO QUICKLY MOVE NORTH AND EAST ACROSS THE
FORECAST AREA...DESPITE INITIAL DRY CONDITIONS PER VERY DRY 12Z
GYX SOUNDING. THIS IS ALSO IN GOOD AGREEMENT WITH THE LATEST HRRR
UPDATE THIS HOUR.
THERE MAY CONTINUE TO BE AREAS OF -FZRA EARLY TONIGHT AS BOUNDARY
LAYER TEMPS CONTINUE TO HOVER AROUND FREEZING IN THE NORTHERN
SHELTERED VALLEYS. HAVE ISSUED A FREEZING RAIN ADVISORY UNTIL 10
PM FOR THIS REGION. HAVE ALSO ADDED A CHANCE FOR FREEZING RAIN IN
CENTRAL NH AND THE FOOTHILLS OF MAINE THROUGH THIS EVENING BASED
ON CURRENT AND SHORT TERM FORECAST CONDITIONS.
REST OF GRIDS WILL REMAIN UNCHANGED...HOWEVER...MAY NEED TO TWEAK
WIND GUST GRIDS TO BETTER MATCH CURRENT PRODUCTS.
&&
.SHORT TERM /WEDNESDAY NIGHT/...
COLDER AIR WILL MOVE BACK INTO THE REGION ON WEDNESDAY AS LOW
PRESSURE CONTINUES TO MOVE OFF TO THE NORTHEAST. EXPECT ANY
SHOWERS DOWNWIND OF THE MOUNTAINS TO END DURING THE MORNING HOURS.
IN THE NORTH WILL SEE RAIN SHOWERS CHANGING TO SNOW SHOWERS IN THE
MOUNTAINS WITH SOME MINOR ACCUMULATIONS POSSIBLE. EXPECT STEADY OR
SLOWLY FALLING TEMPERATURES DURING THE DAY WITH MOST AREAS DIPPING
TO THE FREEZING MARK BY LATE AFTERNOON. EXPECT NORTHWEST WINDS TO
INCREASE SIGNIFICANTLY DURING THE AFTERNOON...POSSIBLY REACHING
ADVISORY LEVELS.
WINDY AND VERY COLD WEDNESDAY NIGHT WITH A CONTINUING CHANCE OF
SNOW SHOWERS IN THE MOUNTAINS. ELSEWHERE SKIES WILL GRADUALLY
CLEAR. EXPECT LOWS OF ZERO TO 5 BELOW IN THE NORTH AND IN THE
LOWER TO MID TEENS IN THE SOUTH.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
UPR LVL CUTOFF OVER THE MARITIMES WITH ASSOCIATED DEEP SFC CYCLONE
WILL SLOWLY LIFT NE ON THURSDAY ALLOWING A MORE UPR LVL ZONAL FLOW
TO SET UP WITH AN EMBEDDED VORTICITY MAX/JET SEGMENT TO MOVE TOWARD
THE NE. THIS BRINGS A WEAK SFC LOW AND LEADING WRM FNT TOWARD NEW
ENGLAND. THESE FEATURES CROSS NEW ENGLAND THURSDAY NGT CREATING
CLOUDS AND SOME -SN. ON FRIDAY A SECOND UPR LVL VORTICITY MAX/JET
SEGMENT IN THE WESTERLY FLOW ALOFT MOVES THRU WITH ANOTHER WEAK SFC
LOW AND ROUND OF SOME -SN.
THIS IS FOLLOWED BY A STRONG UPR LVL SHORT WAVE/VORTICITY MAX ON
SATURDAY. THIS FORMS A SFC LOW ALONG THE MID ATLANTIC COAST THAT
STRENGTHENS AS IT MOVES EAST INTO THE ATLANTIC. THE CURRENT TRACK IS
TOO FAR S TO PROVIDE MUCH IN THE WAY OF PRCP FOR THE FCST AREA...
BUT SOME -SN CAN`T BE RULED OUT...ESPECIALLY IF IT ENDS UP TRACKING
A BIT FURTHER N.
AN UPR LVL RIDGE FOLLOWS THE TROF WITH A SFC RIDGE OF HIGH PRES
CROSSING THE REGION SATURDAY NGT PROVIDING FAIR WX. YET ANOTHER UPR
LVL SHORT WAVE MOVES E INTO THE REGION ON SUNDAY. CURRENT MODEL
FORECASTS SHOW THIS AS A STRONG UPR LVL SYSTEM WHICH BRINGS A SFC
LOW E FROM THE UPR GREAT LAKES TOWARD NRN NEW ENGLAND SUNDAY THEN
CROSSES NRN NEW ENGLAND SUNDAY NGT. THE TRACK OF THIS LOW MAY
BRING IN ENOUGH WARM AIR SO THAT PRCP IS NOT CONFINED TO
SN...THERE COULD BE RA OR EVEN MIXED SN/ICE/RA WITH THIS
EVENT...WITH RA MORE LIKELY ALONG THE COAST AND THE N/MT ZONES
MORE LIKELY TO SEE SN. LOTS OF TIME UNTIL THIS EVENT FOR THE TRACK
AND/OR INTENSITY OF THIS SYSTEM TO CHANGE.
THE LOW INTENSIFIES OVER THE MARITIMES ON MONDAY BRINGING IN MUCH
COLDER CANADIAN AIR ON INCREASING AND VERY GUSTY NW WINDS. -SHSN
PSBL ON MONDAY...ESPECIALLY ACROSS THE N/MT ZONES DUE TO OROGRAPHIC
LIFTING UNDER THE UPR LVL CYCLONIC FLOW. THE COLD BLUSTER WX
CONTINUES MONDAY NGT AND TUESDAY.
GENERALLY USED GFS40...HPC QPF AND BLEND OF MAV/MET MOS FOR THURSDAY
AND THURSDAY NGT. USED GMOS FOR REST OF THE LONG TERM FCST...EXCEPT
USED A BLEND OF GFS AND MEX MOS GUIDANCE FOR MAX AND MIN TEMPS.
&&
.AVIATION /04Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM...MVFR/IFR CEILINGS DEVELOPING THIS EVENING...IMPROVING
TO VFR WEDNESDAY MORNING. VFR WEDNESDAY NIGHT WITH AREAS OF MVFR
CEILINGS AND VSBY IN SNOW SHOWERS IN THE NORTH.
LONG TERM /THURSDAY THROUGH SUNDAY/...MVFR TO MAYBE IFR
CONDITIONS PSBL THURSDAY NGT THRU FRIDAY AS A SERIES OF WEAK
SYSTEMS BRING THE POTENTIAL FOR SOME LGT SN. A STRONGER SYSTEM
BRINGS THE CHC FOR SN AND IFR CONDITIONS ON SATURDAY FOLLOWED BY
ANOTHER STRENGTHENING LOW PRES SYSTEM BRINGING A CHC OF MIXED PRCP
AND IFR CONDITIONS ON SUNDAY.
&&
.MARINE...
SHORT TERM...GALE WARNING THROUGH TONIGHT. RAISED SEAS RELYING
HEAVILY ON THE SWAN GFS MODEL.
LONG TERM /THURSDAY THROUGH SUNDAY/...CD NW FLOW ON THURSDAY MAY
RESULT IN CONTINUED GALE FORCE WINDS... AT LEAST THRU THE MORNING.
THE PRES GRADIENT LETS UP LATER IN THE DAY AS WINDS AND SEAS
SUBSIDE. A SERIES OF WEAK LOW PRES SYSTEMS MOVE THRU THURSDAY NGT
AND FRIDAY BUT CONDITIONS LIKELY TO STAY BELOW SCA LEVELS. LOW
PRES PASSES WELL TO THE S ON SATURDAY SO AGAIN CONDITIONS LIKELY
TO REMAIN BELOW SCA THRESHOLDS. A STRONGER LOW PRES SYSTEM MOVES
IN FOR SUNDAY WHICH MAY PRODUCE SCA WINDS AND SEAS.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WIND ADVISORY UNTIL 5 AM EST WEDNESDAY FOR MEZ023>028.
NH...WIND ADVISORY UNTIL 5 AM EST WEDNESDAY FOR NHZ014.
MARINE...GALE WARNING UNTIL 5 AM EST WEDNESDAY FOR ANZ150>154.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
728 PM EST TUE DEC 27 2011
.SYNOPSIS...
A LOW PRESSURE SYSTEM WAS CROSSING THE AREA THIS EVENING. THE
RAIN WILL GRADUALLY TURN TO SNOW AS COLDER AIR FILTERS IN BEHIND
THE STORM. HIGH PRESSURE WILL BUILD INTO THE REGION PROVIDING A
DRY MIDWEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
700 PM LOCAL UPDATE...UPPER AIR SYSTEM WEAKENING AND SLOWER TO
PUSH IN THE COLD AIR. ADJUSTED TIMING OF CHANGE OVER. ALSO
TEMPERATURES SLOWER TO DROP AND ADJUSTED BASED ON CURRENT
TEMPERATURE TRENDS. WINDS HAVE ALL GENERALLY ALL SHIFTED TO
SOUTHWEST AND GUSTY.
PREVIOUS DISCUSSION FOLLOWS... THE LATEST RUC MID-LEVEL ANALYSIS
INDICATES TWO TROUGH FEATURES THAT ARE SLIGHTLY OFF IN TIMING AND
PHASING. THE NORTHERN AND SLOWER FEATURE IS LOCATED ACROSS LAKE
MICHIGAN WITH THE SOUTHERN BRANCH ALONG ACROSS WESTERN
PENNSYLVANIA. AN 850MB CLOSED LOW IS LOCATED ACROSS NORTH-CENTRAL
OHIO. AHEAD OF THIS FEATURE, A WARM WEDGE OF 850 TEMPS AT 1-3C IS
BEGINNING TO EDGE EASTWARD OUT THE AREA INTO CENTRAL PA WITH 0C TO
-2C 850 TEMPS ENCROACHING EASTERN OHIO. THE WEDGE HAS HELD MOST OF
THE DAY WITH RAIN BEING THE DOMINANT TYPE OF PRECIP ACROSS THE
AREA. THERE HAS HOWEVER BEEN A MIX ALONG THE I-80 CORRIDOR. AT THE
SURFACE A 994MB LOW IS LOCATED ACROSS LAKE ERIE WITH A WIND SHIFT
TO NORTHWESTERLY BEHIND IT. ON THE BACK-SIDE OF THE LOW, A
DEFORMATION ZONE WITH MODERATE SNOW IS WEAKENING AS IT MOVES INTO
WESTERN OHIO.
TONIGHT...THE TROUGH AND SURFACE LOW WILL SHIFT NORTHEAST OF THE
AREA INTO NEW YORK, WITH COLD AIR ADVECTION ALLOWING FOR
PRECIPITATION TO QUICKLY TURN OVER TO ALL SNOW. THE 700MB
DEFORMATION ZONE WILL CROSS THE AREA, ALLOWING FOR AN INITIAL
QUICK BURST OF A HALF OF AN INCH TO AN INCH ACROSS MUCH OF THE
AREA. HAVE ISSUED AN SPS TO HIGHLIGHT THIS FEATURE. AFTER THE INITIAL
BURST, A NORTHWESTERLY FLOW WILL ALLOW FOR SNOW SHOWERS ACROSS THE
AREA. UPSLOPING ACROSS THE RIDGES ALONG WITH A SLIGHTLY FASTER
CHANGEOVER FOR AREAS NORTH OF PITTSBURGH WILL ALLOW FOR 2 TO 4
INCHES BY DAWN ON WEDNESDAY. OVERNIGHT LOWS ARE CLOSER TO LAMP
GUIDANCE, RANGING FROM THE MID TO UPPER 20S ACROSS THE AREA. THE
QUICK DROP BELOW FREEZING BY MIDNIGHT, WILL LEAD TO SOME ICY AND
SNOW-COVERED ROADS THROUGH DAWN.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
LAKE EFFECT SNOW SHOWERS WILL LINGER EARLY ON WEDNESDAY, ALTHOUGH
DO NOT EXPECT ACCUMULATIONS TO AMOUNT TO MORE THAN AN INCH WITH
LOWERED INVERSION HEIGHTS LIMITING INSTABILITY. A SURFACE HIGH
WILL THEN BUILD IN THROUGH THURSDAY. TEMPERATURES WILL BE AROUND 5
DEGREES BELOW NORMAL ON WEDNESDAY AND WEDNESDAY NIGHT AS ARCTIC
AIR SETTLES INTO THE AREA IN THE WAKE OF THE LOW.
THERE IS SOME UNCERTAINTY IN TIMING OF A SERIES OF SHORT WAVES
CROSSING THE AERA THURSDAY INTO FRIDAY. SCHC POPS ARE INTRODUCED
NORTH OF PITTSBURGH ON THURSDAY, INCREASING TO CHANCE THURSDAY
NIGHT, WITH THE BEST CHANCE ON FRIDAY AS A MORE PRONOUNCED TROUGH
AXIS CROSSES THE AREA. MODEL THICKNESSES INDICATE A MIX OF RAIN
AND SNOW SHOWERS FOR THE AREA, SO DO NOT ANTICIPATE ANY
SIGNIFICANT ACCUMULATIONS WITH THE WAVES AS THEY MOVE THROUGH.
TEMPS WILL BE AROUND 5 DEGREES ABOVE SEASONAL NORMALS THURSDAY
INTO FRIDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
FAST MOVING SYSTEMS IN A PROGRESSIVE FLOW WILL BRING TEMPERATURES
AVERAGING CLOSE TO NORMAL AND CHANCES FOR RAIN OR SNOW SHOWERS
FOR LATE WEEK INTO THE WEEKEND. STRONGER DISTURBANCE WILL TAP
INTO THE NORTHERN BRANCH OF THE JET STREAM BRINGING PROGRESSIVELY
COLDER AIR INTO THE REGION BY TUESDAY NIGHT.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
WINDS CURRENTLY ALL SOUTHWEST AND GUSTING EXCEPT FOR DUJ. WILL
KEEP LLWS IN DUJ UNTIL WIND SHIFT (AROUND 01Z-02Z). WIND PROFILES
UNIDIRECTIONAL AND TURBULENCE IS MECHANICAL. ZZV DROPPED 2
DEGREES THIS HOUR AND SHOULD CHANGE OVER BY 01Z. SIGNIFICANT UPPER
LEVEL WAVE HAS WEAKENED FROM EARLIER IN DAY AND PREVIOUS ZONE OF
MODERATE SNOW HAS SLACKENED. EXPECT ONCE CHANGE OVER OCCURS TO
DROP TO AROUND 2 MILES THROUGH LATE EVENING AND EARLY MORNING.
WILL TIME CHANGE-OVER FROM 01Z THROUGH ABOUT 06Z OR SO ACROSS
TERMINALS. WILL KEEP WINDS GUSTY AND BRING THEM AROUND TO WEST AND
THEN NORTHWEST BY MORNING.
OUTLOOK...THURSDAY THROUGH SUNDAY... SERIES OF WEAK WEATHER
SYSTEMS PUSHING ACROSS THE GREAT LAKES THROUGH THE PERIOD WITH
SCATTERED SNOW AND RAIN SHOWERS. GENERALLY VFR BUT MVFR IN
PRECIPITATION. LARGER STORM SYSTEM WITH TRAILING FRONT TO PUSH
EAST FOR SUNDAY WITH A LITTLE MORE WIDESPREAD PRECIPITATION
EXPECTED.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR MDZ001.
OH...WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR OHZ041.
PA...WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR
PAZ007>009-013>016-020>023-073>076.
WV...WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR WVZ023-
041.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
643 PM EST TUE DEC 27 2011
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL CROSS THE AREA, SPREADING MOSTLY RAIN OVER
THE UPPER OHIO VALLEY REGION TODAY BEFORE PRECIPITATION CHANGES TO
ALL SNOW TONIGHT. HIGH PRESSURE WILL THEN BUILD IN FOR A DRY MID-
WEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
THE LATEST RUC MID-LEVEL ANALYSIS INDICATES TWO TROUGH FEATURES
THAT ARE SLIGHTLY OFF IN TIMING AND PHASING. THE NORTHERN AND
SLOWER FEATURE IS LOCATED ACROSS LAKE MICHIGAN WITH THE
SOUTHERN BRANCH ALONG ACROSS WESTERN PENNSYLVANIA. AN 850MB CLOSED
LOW IS LOCATED ACROSS NORTH-CENTRAL OHIO. AHEAD OF THIS FEATURE,
A WARM WEDGE OF 850 TEMPS AT 1-3C IS BEGINNING TO EDGE EASTWARD
OUT THE AREA INTO CENTRAL PA WITH 0C TO -2C 850 TEMPS ENCROACHING
EASTERN OHIO. THE WEDGE HAS HELD MOST OF THE DAY WITH RAIN BEING
THE DOMINANT TYPE OF PRECIP ACROSS THE AREA. THERE HAS HOWEVER
BEEN A MIX ALONG THE I-80 CORRIDOR. AT THE SURFACE A 994MB LOW IS
LOCATED ACROSS LAKE ERIE WITH A WIND SHIFT TO NORTHWESTERLY BEHIND
IT. ON THE BACK-SIDE OF THE LOW, A DEFORMATION ZONE WITH MODERATE
SNOW IS WEAKENING AS IT MOVES INTO WESTERN OHIO.
THIS EVENING...THE NORTHERN AND SOUTHERN BRANCHES WILL ATTEMPT
TO PHASE INTO A MID-LEVEL TROUGH WITH THE SURFACE LOW MOVING INTO
WESTERN NY. THE 850MB LOW WILL PASS NORTHEAST OF THE AREA, WRAPPING
COLDER AIR IN BEHIND IT. IN ADDITION, RUC/NAM HINT AT THE RE-
DEVELOPMENT OF A 700MB DEFORMATION ZONE, WHICH WILL BRING A SHOT
OF MODERATE SNOW TO THE AREA THIS EVENING. THE MOST UNCERTAINTY IN
THE FORECAST LIES IN REGARDS TO WHETHER THE DEFORMATION ZONE WILL
CONTINUE TO WEAKEN OR RE-DEVELOP. HAVE SIDED WITH IT RE-
DEVELOPING. AS SURFACE WINDS SHIFT TO NORTHWESTERLY, THE
CHANGEOVER TO SNOW WILL QUICKLY ENSUE. TEMPS WILL REMAIN MID 40S
IN LOCATIONS WEST OF CHESTNUT RIDGE WHERE DOWNSLOPING IS
OCCURRING. OTHERWISE, TEMPS WILL RANGE FROM THE MID 30S ACROSS THE
I-80 CORRIDOR TO THE LOWER 40S ACROSS NORTH-CENTRAL WV. THE
COLDEST AIR REMAINS TRAPPED IN THE VALLEYS OF GARRETT COUNTY,
WHERE TEMPS IN THE LOWER TO MID 30S WILL ALLOW FOR SOME SLEET TO
MIX IN WITH RAIN. WILL CONTINUE TO MONITOR THIS AREA FOR FREEZING
RAIN BEFORE THE TURN OVER TO SNOW.
TONIGHT...THE TROUGH AND SURFACE LOW WILL SHIFT NORTHEAST OF THE
AREA INTO NEW YORK, WITH COLD AIR ADVECTION ALLOWING FOR
PRECIPITATION TO QUICKLY TURN OVER TO ALL SNOW. THE 700MB
DEFORMATION ZONE WILL CROSS THE AREA, ALLOWING FOR AN INITIAL
QUICK BURST OF A HALF OF AN INCH TO AN INCH ACROSS MUCH OF THE
AREA. HAVE ISSUED AN SPS TO HIGHLIGHT THIS FEATURE. AFTER THE INITIAL
BURST, A NORTHWESTERLY FLOW WILL ALLOW FOR SNOW SHOWERS ACROSS THE
AREA. UPSLOPING ACROSS THE RIDGES ALONG WITH A SLIGHTLY FASTER
CHANGEOVER FOR AREAS NORTH OF PITTSBURGH WILL ALLOW FOR 2 TO 4
INCHES BY DAWN ON WEDNESDAY. OVERNIGHT LOWS ARE CLOSER TO LAMP
GUIDANCE, RANGING FROM THE MID TO UPPER 20S ACROSS THE AREA. THE
QUICK DROP BELOW FREEZING BY MIDNIGHT, WILL LEAD TO SOME ICY AND
SNOW-COVERED ROADS THROUGH DAWN.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
LAKE EFFECT SNOW SHOWERS WILL LINGER EARLY ON WEDNESDAY, ALTHOUGH
DO NOT EXPECT ACCUMULATIONS TO AMOUNT TO MORE THAN AN INCH WITH
LOWERED INVERSION HEIGHTS LIMITING INSTABILITY. A SURFACE HIGH
WILL THEN BUILD IN THROUGH THURSDAY. TEMPERATURES WILL BE AROUND 5
DEGREES BELOW NORMAL ON WEDNESDAY AND WEDNESDAY NIGHT AS ARCTIC
AIR SETTLES INTO THE AREA IN THE WAKE OF THE LOW.
THERE IS SOME UNCERTAINTY IN TIMING OF A SERIES OF SHORT WAVES
CROSSING THE AERA THURSDAY INTO FRIDAY. SCHC POPS ARE INTRODUCED
NORTH OF PITTSBURGH ON THURSDAY, INCREASING TO CHANCE THURSDAY
NIGHT, WITH THE BEST CHANCE ON FRIDAY AS A MORE PRONOUNCED TROUGH
AXIS CROSSES THE AREA. MODEL THICKNESSES INDICATE A MIX OF RAIN
AND SNOW SHOWERS FOR THE AREA, SO DO NOT ANTICIPATE ANY
SIGNIFICANT ACCUMULATIONS WITH THE WAVES AS THEY MOVE THROUGH.
TEMPS WILL BE AROUND 5 DEGREES ABOVE SEASONAL NORMALS THURSDAY
INTO FRIDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
FAST MOVING SYSTEMS IN A PROGRESSIVE FLOW WILL BRING TEMPERATURES
AVERAGING CLOSE TO NORMAL AND CHANCES FOR RAIN OR SNOW SHOWERS
FOR LATE WEEK INTO THE WEEKEND. STRONGER DISTURBANCE WILL TAP
INTO THE NORTHERN BRANCH OF THE JET STREAM BRINGING PROGRESSIVELY
COLDER AIR INTO THE REGION BY TUESDAY NIGHT.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
WINDS CURRENTLY ALL SOUTHWEST AND GUSTING EXCEPT FOR DUJ. WILL
KEEP LLWS IN DUJ UNTIL WIND SHIFT (AROUND 01Z-02Z). WIND PROFILES
UNIDIRECTIONAL AND TURBULENCE IS MECHANICAL. ZZV DROPPED 2
DEGREES THIS HOUR AND SHOULD CHANGE OVER BY 01Z. SIGNIFICANT UPPER
LEVEL WAVE HAS WEAKENED FROM EARLIER IN DAY AND PREVIOUS ZONE OF
MODERATE SNOW HAS SLACKENED. EXPECT ONCE CHANGE OVER OCCURS TO
DROP TO AROUND 2 MILES THROUGH LATE EVENING AND EARLY MORNING.
WILL TIME CHANGE-OVER FROM 01Z THROUGH ABOUT 06Z OR SO ACROSS
TERMINALS. WILL KEEP WINDS GUSTY AND BRING THEM AROUND TO WEST AND
THEN NORTHWEST BY MORNING.
OUTLOOK...THURSDAY THROUGH SUNDAY... SERIES OF WEAK WEATHER
SYSTEMS PUSHING ACROSS THE GREAT LAKES THROUGH THE PERIOD WITH
SCATTERED SNOW AND RAIN SHOWERS. GENERALLY VFR BUT MVFR IN
PRECIPITATION. LARGER STORM SYSTEM WITH TRAILING FRONT TO PUSH
EAST FOR SUNDAY WITH A LITTLE MORE WIDESPREAD PRECIPITATION
EXPECTED.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR MDZ001.
OH...WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR OHZ041.
PA...WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR
PAZ007>009-013-015-016.
WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR PAZ014-
020>023-073>076.
WV...WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR WVZ023-
041.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
404 PM EST MON DEC 26 2011
.SYNOPSIS...
HIGH PRESSURE WILL MOVE INTO THE MID-ATLANTIC WITH A DRY FORECAST
TONIGHT. A LOW PRESSURE SYSTEM WILL MOVE INTO THE AREA TUESDAY,
BRINGING MOSTLY RAIN TO THE AREA WITH A MIX OF RAIN AND SNOW
POSSIBLE NORTH OF PITTSBURGH. PRECIPITATION WILL CHANGE TO ALL SNOW
TUESDAY NIGHT AS THE LOW SHIFTS NORTHEAST OF THE AREA.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
THE LATEST RUC ANALYSIS INDICATES A WEAK 500MB RIDGE CENTERED
ACROSS THE OHIO VALLEY. AT THE SURFACE, A 1027MB HIGH IS CENTERED
WESTERN PENNSYLVANIA. THIS FEATURE HAS CONTRIBUTED TO CLEARING
SKIES, ALTHOUGH CIRRUS IS BEGINNING TO SPILL INTO THE AREA AHEAD
OF THE NEXT SYSTEM TO THE SOUTHWEST.
TONIGHT...THE SURFACE HIGH WILL MOVE OFF THE MID-ATLANTIC COAST
OVERNIGHT AS CYCLOGENESIS OCCURS ACROSS THE CENTRAL GULF COAST.
THIS LOW WILL CONTINUE TO STRENGTHEN, PROGGED TO BE OVER THE TN
VALLEY BY DAWN ON TUESDAY. WEAK RIDGING WILL KEEP THE FORECAST DRY
ACROSS MOST OF THE AREA UNTIL NEAR DAWN ON TUESDAY WHEN 290K
ISENTROPIC LIFT SHIFTS EASTERN OHIO. TEMPS MAY DROP A FEW DEGREES
INITIALLY TONIGHT, ALTHOUGH 850MB TEMPS SUPPORT WARM AIR ADVECTION
KICKING IN, WITH TEMPS STEADYING OFF AND BEGINNING TO INCREASE
AFTER 06Z. THUS, OVERNIGHT LOWS WILL LIKELY BE REACHED AROUND
MIDNIGHT, RANGING FROM NEAR 30 ACROSS I-80 CORRIDOR AND EASTERN
RIDGES TO THE MID 30S ACROSS PORTIONS OF EASTERN OHIO AND NORTH-
CENTRAL WV.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
STILL SOME UNCERTAINTY IN THE TIMING OF PRECIP TYPE WITH THE
FORECAST ON TUESDAY INTO TUESDAY NIGHT, ALTHOUGH OPERATIONAL MODELS
HAVE SHOWN CONSISTENCY BETWEEN THE 00Z/12Z RUNS WITH A POTENTIAL
RAIN/SNOW EVENT FOR THE UPPER OHIO VALLEY.
IN THE MID TO UPPER LEVELS THERE WILL BE TWO PIECES OF ENERGY
APPROACHING FROM THE WEST, A NORTHERN STREAM TROUGH APPROACHING FROM
THE UPPER MIDWEST AND A SOUTHERN STREAM CLOSED LOW ACROSS THE
ARKLATEX THAT WILL OPEN UP INTO A TROUGH AS IT CROSSES THE TENNESSEE
VALLEY. THE SOUTHERN STREAM TROUGH LOOKS TO MOVE A BIT FASTER INTO
THE AREA BEFORE THE NORTHERN SYSTEM, THUS LIMITING THEIR ABILITY TO
PHASE.
IN THE LOWER LEVELS, THE NORTHERN AND SOUTHERN STREAM SURFACE LOWS
DO NOT MERGE UNTIL THE SYSTEM HAS PUSHED NORTHEAST OF THE AREA INTO
NEW ENGLAND. IN ADDITION, MODEL SOUNDINGS INDICATE A WARM NOSE OF
3-5C IN A 1000-800MB MELTING LAYER BETWEEN 12Z TUES AND 00Z TUES. IN
THIS SCENARIO, THE BULK OF THE HEAVIEST PRECIPITATION WILL CROSS THE
APPALACHIANS WITH THE WARM WEDGE KEEPING PRECIP IN THE FORM OF RAIN
THROUGHOUT THE DAY TUESDAY. DO HAVE A FEW HOURS WITH THE CHANCE OF
FREEZING RAIN FOR THE VALLEYS IN GARRETT AND TUCKER COUNTIES AT
THE ONSET OF PRECIP, SO WILL NEED TO MONITOR TEMPS THERE. TEMPS ON
TUESDAY WERE ADJUSTED UP A FEW DEGREES FOR AREAS NORTH OF THE I-70
CORRIDOR. HIGHS WILL RANGE FROM THE MID 40S ACROSS PORTIONS OF
EASTERN OHIO, NORTH- CENTRAL WV, AND SOUTHWEST PA TO THE UPPER 30S
ACROSS I-80 CORRIDOR.
TUESDAY NIGHT...THE NORTHERN STREAM MID-LEVEL TROUGH WILL SHIFT EAST
ACROSS THE AREA AS THE MERGED SURFACE LOW WILL MOVE NORTHWARD FROM
THE NY INTO EASTERN CANADA. THIS WILL ALLOW FOR COLD AIR ADVECTION
TO ENSUE BEGINNING AROUND 00Z. THE TURN OVER TO SNOW SEEMS QUITE
APPARENT SHORTLY AFTER SUNSET, ALTHOUGH THERE IS UNCERTAINTY IN
REGARDS TO HOW MUCH MOISTURE AND LIFT WILL BE LINGERING WITH THIS
SYSTEM.
THE NAM INDICATES A WEAK DEFORMATION ZONE PASSING ACROSS THE AREA
WITH A NORTHWESTERLY, UPSLOPING FLOW ENSUING. AT THIS TIME, BELIEVE
THE CHANGEOVER TO SNOW WILL OCCUR NEAR SUNSET THE I-80 CORRIDOR WITH
UPSLOPING KICKING IN FOR THE RIDGES AFTER MIDNIGHT. WITH THE SPREAD OF
OPERATIONAL MODELS, THIS SCENARIO LIMITS THE SNOW FORECAST TO LESS
THAN 2 INCHES FOR THE LOWLANDS OF SOUTHWEST PA WITH LESS THAN AN
INCH IN OHIO AND NORTHERN WV. POTENTIAL WINTER WEATHER ADVISORY
CRITERIA COULD BE REACHED WITH 2-4 INCHES FOR THE I-80 CORRIDOR
AND EASTERN RIDGES. REGARDLESS OF THE AMOUNT OF SNOW, TEMPS
DROPPING INTO THE UPPER 20S TUESDAY NIGHT AND RAIN PRECEDING THE
CHANGEOVER COULD CONTRIBUTE TO SLICK CONDITIONS ON ROADWAYS
DEVELOPING ACROSS MUCH OF WESTERN PA, NORTH-CENTRAL WV, AND
WESTERN MD TUESDAY NIGHT.
WEDNESDAY AND WEDNESDAY NIGHT...A FEW LINGERING SNOW SHOWERS WILL BE
POSSIBLE IN A NORTHWESTERLY FLOW IN THE WAKE OF THIS SYSTEM EARLY
IN THE DAY. THERE IS REASONABLE ECMWF/GFS AGREEMENT AFTER THIS POINT
THAT HIGH PRESSURE WILL BUILD IN FROM THE SOUTHWEST AND ALLOW FOR
DRY WEATHER. WITH ONGOING COLD AIR ADVECTION, TEMPS WILL BE FAIRLY
STEADY IN THE UPPER 20S TO LOWER 30S ON WEDNESDAY. STRONG
RADIATIONAL COOLING ON WEDNESDAY NIGHT WILL ALLOW FOR OVERNIGHT
LOWS RANGING FROM THE UPPER TEENS ACROSS THE EASTERN RIDGES AND
I-80 CORRIDOR TO THE LOWER 20S ELSEWHERE.
THURSDAY...GFS/NAM/ECMWF ARE HINTING AT A SHORT WAVE DROPPING FROM
THE NORTHERN GREAT LAKES INTO NY. THIS SYSTEM MAY CLIP THE UPPER
OHIO VALLEY WITH CHANCE POPS NORTH OF PITTSBURGH. 1000-500MB
THICKNESS 5400M LINE ENCROACHES FROM THE SOUTHWEST THROUGHOUT THE
DAY, ALTHOUGH BELIEVE PRECIP WILL BE MOSTLY IN THE FORM OF SNOW
SHOWERS. IF THE SYSTEM DROPS FURTHER SOUTH, BELIEVE ITS ASSOCIATED
COLDER AIR WILL DOMINATE. TEMPERATURES WILL BE NEAR NORMAL SEASONAL
VALUES.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
FAST MOVING SYSTEMS IN PROGRESSIVE FLOW WILL BRING TEMPERATURES
AVERAGING ABOVE NORMAL AND CHANCES FOR RAIN OR SNOW SHOWERS FOR
LATE WEEK INTO THE WEEKEND. LONG TERM PERIOD WAS FORECAST CLOSE TO
HPC PROGS WHICH CONTINUE TO TREND TOWARD THE ECMWF.
&&
.AVIATION /21Z MONDAY THROUGH SATURDAY/...
EROSION OF THE STRATOCU DECK FROM WEST TO EAST THIS AFTERNOON WILL
LEAD TO VFR OVERNIGHT. AS LOW PRESSURE MOVES NORTHEAST INTO THE OHIO
VALLEY RAIN WILL OVER SPREAD THE REGION TUESDAY WITH CIGS AND VSBY
REDUCED TO IFR FROM MID MORNING WEST TO MID AFTERNOON FAR EAST.
EXPECT IFR TO CONTINUE INTO TUESDAY NIGHT AS PRECIPITATION
TRANSITIONS TO SNOW IN THE EVENING WITH IFR SNOW SHOWERS IN
NORTHWEST FLOW BEHIND LOW PRESSURE TUESDAY NIGHT.
OUTLOOK...WEDNESDAY THROUGH SATURDAY...
CONDITIONS WILL IMPROVE DURING THE DAY WEDNESDAY WITH VFR
EXPECTED BY LATE DAY AS A WEAK SURFACE RIDGE MOVES EAST. A SERIES
OF FAST MOVING WEATHER SYSTEMS WILL THEN CROSS THE REGION THURSDAY
THROUGH SATURDAY WITH RESTRICTIONS POSSIBLE AT TIMES THROUGH THE
PERIOD.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1253 PM EST MON DEC 26 2011
.SYNOPSIS...
HIGH PRESSURE WILL PROVIDE DRY WEATHER AND SEASONABLE TEMPERATURES
FOR THE REST OF TODAY AND TONIGHT. A STORM SYSTEM WILL BRING A MIX
OF RAIN AND SNOW TO THE AREA TUESDAY AND THEN SNOW TUESDAY
NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
18Z ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED TO ADJUST
SKY GRIDS AND TO WARM OVERNIGHT TEMPS AFTER 06Z TONIGHT.
THE LATEST RUC ANALYSIS INDICATES A WEAK 500MB RIDGE CENTERED
ACROSS THE GREAT LAKES WITH THE UPPER OHIO VALLEY IN A
NORTHWESTERLY FLOW AHEAD OF THIS FEATURE. MOIST 850MB FLOW OFF IS
CUTTING OFF WITH STRATOCUMULUS LINGERING EAST OF PITTSBURGH. AT
THE SURFACE, A 1029MB HIGH IS CENTERED ACROSS SOUTHERN OHIO. THIS
FEATURE IS MOVING NORTHEAST TOWARD THE AREA, CONTRIBUTING TO THE
ERODING CLOUD DECK WITH CLEARING MOVING INTO WESTERN PENNSYLVANIA.
TODAY...THE WEAK RIDGE WILL MOVE ACROSS THE AREA WITH THE SURFACE
HIGH MOVING INTO THE MID-ATLANTIC. THIS WILL ALLOW FOR THE CLOUD
DECK TO ERODE, WITH MOSTLY SUNNY SKIES BY THIS AFTERNOON. CIRRUS
WILL THEN BEGIN TO ADVECT INTO THE AREA FROM THE SOUTHWEST THIS
EVENING. TAKING INTO ACCOUNT LATEST OBS AND LAMP GUIDANCE, TEMPS
HAVE BEEN WARMED A FEW DEGREES. HIGHS WILL RANGE FROM THE NEAR 40
ACROSS THE EASTERN RIDGES AND I-80 CORRIDOR TO THE MID 40S IN
PORTIONS OF EASTERN OHIO AND NORTH-CENTRAL WV.
TONIGHT...THE SURFACE HIGH WILL MOVE OFF THE MID-ATLANTIC COAST
LATE AS CYCLOGENESIS OCCURS ACROSS THE CENTRAL GULF COAST. THIS
LOW WILL CONTINUE TO STRENGTHEN, PROGGED TO BE OVER THE TN VALLEY
BY DAWN ON TUESDAY. WEAK RIDGING WILL KEEP THE FORECAST DRY ACROSS
MOST OF THE AREA UNTIL NEAR DAWN ON TUESDAY WHEN 290K ISENTROPIC
LIFT SHIFTS EASTERN OHIO. TEMPS MAY DROP A FEW DEGREES INITIALLY
TONIGHT, ALTHOUGH 850MB TEMPS SUPPORT WARM AIR ADVECTION KICKING
IN, WITH TEMPS STEADYING OFF AND BEGINNING TO INCREASE AFTER 06Z.
THUS, OVERNIGHT LOWS WILL LIKELY BE REACHED AROUND MIDNIGHT,
RANGING FROM NEAR 30 ACROSS I-80 CORRIDOR AND EASTERN RIDGES TO
THE MID 30S ACROSS PORTIONS OF EASTERN OHIO AND NORTH-CENTRAL WV.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
VERY DIFFICULT FORECAST TUESDAY AND TUESDAY NIGHT.
A SFC LOW WILL DEVELOP OVER THE GULF COAST STATES AND MOVE INTO
THE TN VALLEY BY DAWN TUESDAY. AT THE UPPER LEVELS, EASTERN RIDGE
WILL BEGIN TO BREAK DOWN TONIGHT AS UL ENERGY MOVE ACROSS THE
MIDWEST. ALSO, UL LOW WILL MOVE ACROSS THE GULF COAST STATES.
THESE TWO PIECES OF ENERGY WILL BE EXTREMELY IMPORTANT TO
TUESDAY`S FORECAST. THE NORTHERN DISTURBANCE WILL HELP TO PUSH
COLDER AIR TOWARD THE REGION. THE SOUTHERN DISTURBANCE WILL PUSH
MOISTURE NORTHWARD AND ALSO DEVELOP THE SFC LOW. AT THIS POINT, IT
APPEARS THAT THE SOUTHERN ENERGY WILL WIN THE RACE INTO THE AREA.
WHAT THIS MEANS FOR THE FORECAST, IS MORE OF A RAIN EVENT ON
TUESDAY AS THE WARMER AIR WILL INITIALLY COVER THE AREA.
THE FIRST QUESTION TO DEAL WITH IS HOW QUICKLY WILL THE
PRECIPITATION BEGIN. MODELS CONTINUE TO SLOW THE ONSET OF
PRECIPITATION AS THE VERY DRY AIR MASS OVER THE MID-ATLANTIC WILL
NOT EASILY BE MOVED. WILL HOLD OFF ON A MENTION OF POPS UNTIL JUST
BEFORE DAWN TUESDAY OVER THE WEST. ON TUESDAY MORNING, WILL
INCREASE POPS FROM WEST TO EAST AS THE PRECIP SHIELD COVERS THE
ENTIRE AREA. CURRENT BELIEF IS THAT PRECIP WILL BEGIN AS RAIN AS
IT MOVES INTO THE AREA. HOWEVER, AS COLDER AIR MOVES ACROSS THE
MIDWEST, IT APPEARS THAT A MIX OF RAIN AND SNOW IS A GOOD
POSSIBILITY ACROSS THE NORTH AND WEST AS THE DAY PROGRESSES.
THE COLDER AIR SHOULD FINALLY OVERTAKE THE REGION TUESDAY EVENING ON
THE HEELS OF A SFC COLD FRONT. THIS WILL BRING A CHANGE OVER TO
ALL SNOW DURING THE EVENING HOURS. TIMING HERE IS STILL A BIG
QUESTION AS THERE CONTINUE TO BE MODEL DISCREPANCIES AND MANY
VARIABLES CONTRIBUTING TO THE COLD AIR INTRUSION.
RIGHT AFTER 00Z WED, MODELS ARE INDICATING A DEFORMATION ZONE
AND AREA OF MID-LEVEL FRONTOGENESIS DEVELOPING AND SWINGING
THROUGH THE AREA. THESE FEATURES HINT AT THE POSSIBILITY OF A
BAND OF ACCUMULATING SNOW DEVELOPING AND ROTATING THROUGH THE
AREA.
SFC LOW WILL DEEPEN OVER SE PA TUESDAY EVENING AND MOVE RAPIDLY
TOWARD THE NE. WITH THE SFC SYSTEM INCREASING FORWARD SPEED,
EXPECT THE SNOW TO TAPER OFF QUICKLY LATE TUESDAY NIGHT.
SFC HIGH WILL BUILD IN ON WEDNESDAY. TEMPERATURES WILL BE BELOW
NORMAL BUT CONDITIONS SHOULD BE DRY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
FAST MOVING SYSTEMS IN PROGRESSIVE FLOW WILL BRING TEMPERATURES
AVERAGING ABOVE NORMAL AND CHANCES FOR RAIN OR SNOW SHOWERS FOR
LATE WEEK INTO THE WEEKEND. LONG TERM PERIOD WAS FORECAST CLOSE TO
HPC PROGS WHICH CONTINUE TO TREND TOWARD THE ECMWF.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
EROSION OF THE STRATOCU DECK FROM WEST TO EAST THIS AFTERNOON WILL
LEAD TO VFR OVERNIGHT. AS LOW PRESSURE MOVES NORTHEAST INTO THE OHIO
VALLEY RAIN WILL OVER SPREAD THE REGION TUESDAY WITH CIGS AND VSBY
REDUCED TO IFR FROM MID MORNING WEST TO MID AFTERNOON FAR EAST.
EXPECT IFR TO CONTINUE INTO TUESDAY NIGHT AS PRECIPITATION
TRANSITIONS TO SNOW IN THE EVENING WITH IFR SNOW SHOWERS IN
NORTHWEST FLOW BEHIND LOW PRESSURE TUESDAY NIGHT.
OUTLOOK...WEDNESDAY THROUGH SATURDAY...
CONDITIONS WILL IMPROVE DURING THE DAY WEDNESDAY WITH VFR
EXPECTED BY LATE DAY AS A WEAK SURFACE RIDGE MOVES EAST. A SERIES
OF FAST MOVING WEATHER SYSTEMS WILL THEN CROSS THE REGION THURSDAY
THROUGH SATURDAY WITH RESTRICTIONS POSSIBLE AT TIMES THROUGH THE
PERIOD.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
958 AM EST MON DEC 26 2011
.SYNOPSIS...
HIGH PRESSURE WILL PROVIDE DRY WEATHER AND SEASONABLE TEMPERATURES
TODAY. A STORM SYSTEM WILL BRING A MIX OF RAIN AND SNOW TO THE AREA
TUESDAY AND THEN SNOW TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
15Z ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED TO ADJUST
SKY GRIDS, ACCOUNTING FOR LINGERING STRATOCUMULUS DECK ACROSS MUCH
OF THE AREA. OTHERWISE, LITTLE CHANGE TO THE GOING FORECAST.
THE LATEST RUC ANALYSIS INDICATES A WEAK 500MB RIDGE CENTERED
ACROSS THE WESTERN GREAT LAKES WITH THE UPPER OHIO VALLEY IN A
NORTHWESTERLY FLOW AHEAD OF THIS FEATURE. MOIST 850MB FLOW OFF OF
LAKE ERIE IS ALLOWING FOR STRATOCUMULUS TO HANG AROUND THIS
MORNING. AT THE SURFACE, A 1030MB HIGH IS CENTERED ACROSS
KENTUCKY. THIS FEATURE IS MOVING NORTHEAST TOWARD THE AREA,
CONTRIBUTING TO THE ERODING CLOUD DECK WITH CLEARING IN EASTERN
OHIO.
TODAY...THE WEAK RIDGE WILL MOVE ACROSS THE AREA WITH THE SURFACE
HIGH MOVING INTO THE MID-ATLANTIC. THIS WILL ALLOW FOR THE CLOUD
DECK TO ERODE, WITH MOSTLY SUNNY SKIES BY THIS AFTERNOON. CIRRUS
WILL THEN BEGIN TO ADVECT INTO THE AREA FROM THE SOUTHWEST THIS
EVENING. TAKING INTO ACCOUNT LATEST OBS, LAMP GUIDANCE, AND THE 12Z
KPIT SOUNDING, FORECAST TEMPS REMAIN A FEW DEGREES BELOW A MAV/MET
BLEND THIS AFTERNOON. HIGHS WILL RANGE FROM THE UPPER 30S ACROSS
THE EASTERN RIDGES AND I-80 CORRIDOR TO THE MID 40S IN PORTIONS OF
EASTERN OHIO AND NORTH-CENTRAL WV.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
VERY DIFFICULT FORECAST TUESDAY AND TUESDAY NIGHT.
AT THE SFC, HIGH PRESSURE WILL MOVE OFF THE VA COAST LATE
TONIGHT. A SFC LOW WILL DEVELOP OVER THE GULF COAST STATES AND
MOVE INTO THE TN VALLEY BY DAWN TUESDAY.
AT THE UPPER LEVELS, EASTERN RIDGE WILL BEGIN TO BREAK DOWN
TONIGHT AS UL ENERGY MOVE ACROSS THE MIDWEST. ALSO, UL LOW WILL
MOVE ACROSS THE GULF COAST STATES. THESE TWO PIECES OF ENERGY WILL
BE EXTREMELY IMPORTANT TO TUESDAY`S FORECAST. THE NORTHERN
DISTURBANCE WILL HELP TO PUSH COLDER AIR TOWARD THE REGION. THE
SOUTHERN DISTURBANCE WILL PUSH MOISTURE NORTHWARD AND ALSO DEVELOP
THE SFC LOW. AT THIS POINT, IT APPEARS THAT THE SOUTHERN ENERGY
WILL WIN THE RACE INTO THE AREA.
WHAT THIS MEANS FOR THE FORECAST, IS MORE OF A RAIN EVENT ON
TUESDAY AS THE WARMER AIR WILL INITIALLY COVER THE AREA.
THE FIRST QUESTION TO DEAL WITH IS HOW QUICKLY WILL THE
PRECIPITATION BEGIN. MODELS CONTINUE TO SLOW THE ONSET OF
PRECIPITATION AS THE VERY DRY AIR MASS OVER THE MID-ATLANTIC WILL
NOT EASILY BE MOVED. WILL HOLD OFF ON A MENTION OF POPS UNTIL JUST
BEFORE DAWN TUESDAY OVER THE WEST. ON TUESDAY MORNING, WILL
INCREASE POPS FROM WEST TO EAST AS THE PRECIP SHIELD COVERS THE
ENTIRE AREA. CURRENT BELIEF IS THAT PRECIP WILL BEGIN AS RAIN AS
IT MOVES INTO THE AREA. HOWEVER, AS COLDER AIR MOVES ACROSS THE
MIDWEST, IT APPEARS THAT A MIX OF RAIN AND SNOW IS A GOOD
POSSIBILITY ACROSS THE NORTH AND WEST AS THE DAY PROGRESSES.
THE COLDER AIR SHOULD FINALLY OVERTAKE THE REGION TUESDAY EVENING ON
THE HEELS OF A SFC COLD FRONT. THIS WILL BRING A CHANGE OVER TO
ALL SNOW DURING THE EVENING HOURS. TIMING HERE IS STILL A BIG
QUESTION AS THERE CONTINUE TO BE MODEL DISCREPANCIES AND MANY
VARIABLES CONTRIBUTING TO THE COLD AIR INTRUSION.
RIGHT AFTER 00Z WED, MODELS ARE INDICATING A DEFORMATION ZONE
AND AREA OF MID-LEVEL FRONTOGENESIS DEVELOPING AND SWINGING
THROUGH THE AREA. THESE FEATURES HINT AT THE POSSIBILITY OF A
BAND OF ACCUMULATING SNOW DEVELOPING AND ROTATING THROUGH THE
AREA.
SFC LOW WILL DEEPEN OVER SE PA TUESDAY EVENING AND MOVE RAPIDLY
TOWARD THE NE. WITH THE SFC SYSTEM INCREASING FORWARD SPEED,
EXPECT THE SNOW TO TAPER OFF QUICKLY LATE TUESDAY NIGHT.
SFC HIGH WILL BUILD IN ON WEDNESDAY. TEMPERATURES WILL BE BELOW
NORMAL BUT CONDITIONS SHOULD BE DRY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
FAST MOVING SYSTEMS IN PROGRESSIVE FLOW WILL BRING TEMPERATURES
AVERAGING ABOVE NORMAL AND CHANCES FOR RAIN OR SNOW SHOWERS FOR
LATE WEEK INTO THE WEEKEND. LONG TERM PERIOD WAS FORECAST CLOSE TO
HPC PROGS WHICH CONTINUE TO TREND TOWARD THE ECMWF.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
GRADUAL EROSION OF THE STRATOCU DECK IS FORECAST FOR THIS MORNING
AS FLOW IMMEDIATELY ABOVE THE BOUNDARY LAYER BACKS TO THE WEST.
EVENTUAL VFR FOR ALL PORTS...WITH SFC WND BACKING TO THE SW WL BE
THE FEATURES OF THE TAF PD.
OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
VFR MAY BE ANTICIPATED INTO TUE MRNG AS HIGH PRESSURE SLIDES OVR THE
REGION. ADVANCING LOW PRESSURE WL THEN SPREAD WIDESPREAD PCPN AND
RESTRICTIONS ON TUESDAY. BY TUESDAY EVE...ALL PCPN WL BE SNOW OVR
THE UPR OHIO VALLEY...BUT THE SYSTEM IS PROGGED TO RAPIDLY EXIT
NEWD...LEAVING COLD NW FLOW AND MVFR STRATOCU AND -SHSN FOR WED. THE
NXT CHC FOR WIDESPREAD RESTRICTIONS IS FORECAST TO COME WITH LATE
WEEK LOW PRESSURE OFF THE GREAT LAKES.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DULUTH MN
356 AM CST WED DEC 28 2011
.SHORT TERM...THE MAIN FORECAST CONCERN IN THE SHORT TERM IS THE
AMOUNT AND LOCATION OF ACCUMULATING SNOWFALL TODAY THROUGH TONIGHT.
AT 330 AM...CLOUDS WERE INCREASING AHEAD OF A WEAK SHORTWAVE AND
UP[PER LEVEL JET MAX TRAVERSING ACROSS MN. STRONG LOW LEVEL WAA
AND THETA-E ADVECTION WAS HELPING TO GENERATE LIGHT SNOW ACROSS
WESTERN MN DESPITE INITIALLY DRY LOW LEVEL AIR. THE HRRR RAPID
REFRESH WAS DEPICTING THE AREA OF CLOUDS/LIGHT SNOW FAIRLY WELL.
THE SHORTWAVE AND 100+ KNOT UPPER LEVEL JET MAX WILL CONTINUE TO
PUSH ACROSS THE NORTHLAND TODAY...PUSHING INTO THE WESTERN GREAT
LAKES BY THIS AFTERNOON. THE LATEST HRRR ACTUALLY SHOWS THE
RETURNS DIMINISHING FOR A TIME THIS EARLY MORNING...BEFORE
INCREASING A BIT AGAIN AS THEY REACH NE MN LATER IN THE MORNING.
THINK THERE IS A CHANCE FOR ABOUT A HALF INCH OF SNOWFALL IN SPOTS
TODAY. COULD SEE A BIT MORE ALONG THE SAWTOOTH MOUNTAINS OF THE
NORTH SHORE...AS WINDS COME AROUND TO THE EAST AND SUPPORT LAKE
EFFECT SNOW SHOWERS.
A STRONGER SYSTEM WILL MOVE IN TONIGHT...AND QUICKLY EXIT THE
REGION ON THURSDAY. HAVE SHIFTED THE FOCUS FOR ACCUMULATING
SNOWFALL A BIT TO THE SOUTH BASED ON THE LATEST 00Z MODEL RUNS.
CURRENT THINKING IS THAT THERE WILL BE A STRIPE OF 1 TO 3 INCHES
FROM THE NORTHERN BRAINERD LAKES REGION...THROUGH THE TWIN PORTS
AND INTO NW WI. ALSO CANNOT RULE OUT A NARROW STRIPE OF 2 TO 4
INCHES OR POSSIBLY A BIT MORE AS THE SYSTEM DROPS TO THE SOUTHEAST
AND LAYS DOWN A SWATH OF ACCUMULATING SNOWFALL. THE NORTH SHORE
SHOULD ALSO SEE HIGHER AMOUNTS DUE TO LAKE EFFECT/LAKE
ENHANCEMENT. IN TERMS OF SURFACE LOW PRESSURE...THE MODELS ARE
FAIRLY SIMILAR...BUT QPF AMOUNTS AND LOCATION DO VARY BETWEEN THE
ECMWF/NAM/GFS AND GEM. WILL TAKE A CONSENSUS SOLUTION. MAY NEED TO
BUMP UP AMOUNTS IN LATER FORECAST PACKAGES. IN THE
GRIDS...CURRENTLY HAVE AMOUNTS SIMILAR TO WHAT IS MENTIONED ABOVE.
THINK THE SYSTEM WILL BE FAIRLY EFFICIENT AT RINGING OUT AVAILABLE
MOISTURE.
THE LOW PRESSURE SYSTEM WILL MOVE OUT OF THE REGION ON
THURSDAY...WITH A BIT OF A BREAK BEFORE THE NEXT SYSTEM ARRIVES
THURSDAY NIGHT. THE NAM SOLUTION WOULD SUPPORT HIGHER POPS FOR
THURSDAY NIGHT...BUT THE ECMWF/GFS KEEP THE ACCUMULATING SNOW
GENERALLY WEST AND SOUTH OF THE CWA.
.LONG TERM...FRIDAY THROUGH TUESDAY.
FRIDAY...THE LONG TERM PERIOD BEGINS WITH LOW CHANCES OF
SNOWFALL...MAINLY DUE TO THE GFS SHOWING A TROUGH MOVING THROUGH
THE NORTHLAND. IT LOOKS LIKE A RIDGE WILL MOVE INTO THE REGION
FRIDAY NIGHT WITH SOUTHERLY WINDS DEVELOPING BY SATURDAY MORNING.
SATURDAY...IT LOOKS LIKE A RELATIVELY WARM DAY. SOUTHWESTERLY WINDS
WILL DEVELOP AS A LOW PRESSURE SYSTEM MOVES FROM CENTRAL MANITOBA TO
WESTERN ONTARIO. THERE MAY BE SOME LIGHT PCPN ACROSS THE NORTHLAND.
CONSIDERING THE WARMER SURFACE TEMPERATURES AND TEMPERATURES
ALOFT...FORECASTED A POSSIBLE MIXTURE OF RAIN AND SNOW. PLUS...MODEL
SOUNDINGS GENERALLY HAD SATURATION ALOFT TO ONLY ABOUT -5 DEGREES
CELSIUS OR LESS UNTIL LATER IN THE EVENING WHEN THE COLDER AIR IS
USHERED INTO THE NORTHLAND. SO WOULD THINK THE PCPN WOULD LIKELY
TURN BACK TO SNOW SATURDAY NIGHT.
SUNDAY AND MONDAY...THE BEGINNING OF NEXT WEEK SHOULD START OFF
COLD. IT LOOKS LIKE THE POSSIBILITY OF LINGERING SYNOPTIC SNOW
ACROSS THE NORTHLAND...AS WELL AS LAKE EFFECT SNOWFALL ALONG PARTS
OF THE SOUTH SHORE. THE MODELS INDICATE VERY COLD 850 HPA WILL WRAP
INTO THE NORTHLAND...AS LOW AS -16 DEGREES CELSIUS. THIS SHOULD MAKE
FOR A SOLID TEMPERATURE DIFFERENCE BETWEEN 850 HPA AND THE LAKE
SURFACE TEMPERATURE...WHICH IS AROUND 4 DEGREES CELSIUS.
&&
.AVIATION.../06Z TAF ISSUANCE/
CURRENTLY VFR CONDITIONS WITH 10K FT CIGS MOVING IN FROM THE WEST
ASSOCIATED WITH AN UPPER S/W. REGIONAL RADAR IS INDICATING A FEW
-SHSN PUSHING INTO NW MN...AND THIS WILL EVENTUALLY MAKE IT TO
BRD BEFORE 12Z AND INL JUST AFTER 12Z. AN HOUR OR TWO LATER TO HIB
AND DLH BEFORE PASSING THROUGH HYR BY 16Z. SNOW SHOWERS WILL BE
VERY SHORT-LIVED WITH THIS FAST MOVING WAVE. CIGS AND VSBYS COULD
DROP TO MID/HIGH-END MVFR THIS MORNING...BUT SHOULD LIFT TO LOW-
END VFR BY THE AFTERNOON. LIGHT SW WINDS WILL VEER TO SOUTH AND
REMAIN LESS THAN 10 KTS OUT OF THE SOUTH THROUGH THIS EVENING. THE
NEXT WAVE QUICKLY MOVES IN FROM THE WEST WED EVENING WITH A BETTER
CHANCE OF MVFR CIGS/VSBYS BEGINNING JUST BEFORE 06Z.
&&
.POINT TEMPS/POPS...
DLH 27 19 29 21 / 30 70 20 20
INL 26 12 26 15 / 30 30 10 20
BRD 32 25 33 24 / 20 60 20 30
HYR 28 20 32 23 / 20 70 30 30
ASX 29 20 33 24 / 20 70 30 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...DAP
LONG TERM....GROCHOCINSKI
AVIATION...GROCHOCINSKI
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1230 PM CST MON DEC 26 2011
...PERIODS OF HEAVY RAIN TODAY WITH QUIETER WEATHER WEEK AHEAD...
.UPDATE...QUICK UPDATE TO KNOCK ABOUT 5 DEGREES OFF AFTERNOON TEMPS
BASED ON LATEST TRENDS. PERSISTENT RAINFALL KEEPING WARM ADVECTION
FROM HELPING NEAR SURFACE TEMPS MUCH. PRECIP TRENDS LOOK GOOD AS
PRECIPITATION IS FILLING BACK IN TO THE S AND W AS IR SHOWS TOPS
RAPIDLY COOLING ACROSS AREA AS ASCENT INCREASES AHEAD OF EJECTING
UPPER LOW.
&&
.AVIATION...MVFR CONDITIONS IN EAST MS WILL SLOWLY DETERIORATE
THROUGH EARLY AFTERNOON LEAVING WIDESPREAD IFR AT ALL TAF SITES AS
AREAS OF STEADY RAIN PERSIST AND INCREASE. THE RISK OF SCATTERED
TSRA WILL ALSO INCREASE THROUGH 06Z TONIGHT PRODUCING OCCASIONAL
LIFR REPORTS BEFORE TAPERING OFF FROM W TO E FROM 08-12Z TUESDAY.
CONDITIONS SHOULD IMPROVE TO MVFR TUESDAY MORNING 14-18Z WITH RAIN
ENDING AND THEN FINALLY VFR CEILINGS RETURNING DURING THE MIDDLE
AFTERNOON. OVERALL SURFACE WINDS WILL PERSIST ESE AT 10-16KTS TODAY
AND BE VARIABLE TONIGHT BEFORE INCREASING FROM THE NW AT 12-18KTS
EARLY TUESDAY MORNING./40/
&&
.HYDROLOGY...SMALL CONVECTIVE COMPLEXES HAVE BEEN AFFECTING PARTS OF
S MS THIS MORNING...WITH A BAND OF 2 TO 4 INCHES OF RAINFALL HAVING
AFFECTED PARTS OF SE MS AND A FFW HAVING BEEN RECENTLY ISSUED. 88D
RADAR ESTIMATES SEEM PRETTY GOOD IN THOSE AREAS BASED ON GROUND
TRUTH REPORTS...AND ARE PROBABLY SEEING STORM TOTALS IN THE LAST 48
HOURS APPROACHING OR SLIGHTLY EXCEEDING 5 INCHES IN PARTS OF THESE
AREAS. UPPER LOW IS STILL WELL WEST OF THE AREA...AND LATEST
GUIDANCE SUGGESTS SEVERAL WAVES OF MODERATE TO HEAVY RAIN WITH
EMBEDDED CONVECTION AFFECTING MUCH OF THE REGION THROUGH
06Z...POSSIBLY LONGER IN EASTERN SECTIONS. GIVEN SEVERAL WAVES OF
HEAVY RAINFALL OVER THE LAST WEEK HAVING LOWERED ALREADY LIMITED
ABILITY OF WINTER GROUND TO HANDLE HEAVY RAIN...AND SEVERAL RIVERS
NOW APPROACHING OR FORECAST TO EXCEED FLOOD STAGE OVER PARTS OF THE
AREA...HAVE WENT AHEAD AND EXPANDED THE WATCH TO ENCOMPASS THE
ENTIRE REGION. LATEST NAM AND HRRR GUIDANCE SUGGESTS WIDESPREAD
ADDITIONAL 1 TO 2 INCH RAINFALL OVER THE ENTIRE AREA WITH EMBEDDED
BANDS OF 3 TO 5 INCHES WHERE TRAINING OF HEAVIER SHOWERS/STORMS
OCCURS. /08/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 55 43 54 34 / 100 100 3 0
MERIDIAN 57 47 55 31 / 100 100 8 0
VICKSBURG 55 41 54 32 / 100 94 3 0
HATTIESBURG 62 48 58 35 / 100 100 9 0
NATCHEZ 58 42 54 34 / 100 86 3 0
GREENVILLE 51 41 52 33 / 100 100 4 0
GREENWOOD 51 42 52 31 / 100 100 11 0
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...FLOOD WATCH THROUGH MIDNIGHT CST FOR ALL ZONES.
LA...FLOOD WATCH THROUGH MIDNIGHT CST FOR ALL ZONES.
AR...FLOOD WATCH THROUGH MIDNIGHT CST FOR ALL ZONES.
&&
$$
08/JA/15
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1005 AM CST MON DEC 26 2011
...PERIODS OF HEAVY RAIN TODAY WITH QUIETER WEATHER WEEK AHEAD...
.UPDATE...RADAR DEPICTS LARGE AREA OF MODERATE TO HEAVY RAIN
COVERING MUCH OF THE FORECAST AREA THIS MORNING. HEAVIEST RAIN WITH
EMBEDDED CONVECTIVE BANDS IS ALONG AND SE OF THE NATCHEZ TRACE
PARKWAY. NONE OF THE MODELS SEEM TO BE DOING A VERY GOOD JOB OF
HANDLING THIS AREA OF HEAVY RAINFALL WITH MODELS SHOWING LIMITED QPF
OVER EASTERN AREAS THROUGH EARLY AFTERNOON...EVEN THE LATEST 12Z
GFS/NAM. WATER VAPOR SHOWS UPPER LOW NEAR KMAF FINALLY MAKING A MOVE
TO THE ESE. DISCOUNTING THE MODEL QPF FORECASTS AND LOOKING AT THE
MASS FIELDS...APPEARS AS THOUGH CURRENT ACTIVITY OVER AREA IS AT
NOSE OF 325+K 850 MB THETA-E AXIS OVER SE LA IN ZONE OF INCREASING
ISENTROPIC ASCENT. WOULD APPEAR AS THOUGH THIS ZONE WILL SHIFT VERY
LITTLE DURING THE DAY AS UPPER LOW BEGINS TO MOVE EAST AND
EVERYTHING ESSENTIALLY WAITS FOR ITS APPROACH. BASED ON THIS WOULD
EXPECT AREAS OF MODERATE TO HEAVY RAIN TO CONTINUE TO DEVELOP AND
FEED ACROSS THE AREA THROUGH THE EVENING HOURS. WOULD ANTICIPATE TWO
MAIN AXES OF HEAVIEST RAIN...ONE OVER THE ARKLAMISS DELTA WHERE A
SWATH OF HEAVIER RAIN SHOULD OCCUR DUE TO THE FORCING ASSOCIATED
DIRECTLY WITH THE UPPER LOW...AND THE OTHER WITH BANDS OF HEAVIER
RAIN AND EMBEDDED CONVECTION OVER THE SOUTHEAST HALF OF THE AREA
ASSOCIATED WITH THE AFOREMENTIONED AXIS OF ISENTROPIC UPGLIDE AND
ELEVATED INSTABILITY. AN ADDITIONAL WIDESPREAD 1 TO 3 INCHES WITH
EMBEDDED HEAVIER TOTALS APPEARS LIKELY OVERALL...WITH ACTIVITY
ENDING FROM THE WEST BETWEEN 03Z AND 09Z TONIGHT AS UPPER SYSTEM
FINALLY SWINGS THROUGH THE AREA.
AS FAR AS FORECAST SPECIFICS...MAIN CHANGE WAS TO ADD HEAVY RAIN TO
THE GRIDS FOR THE ENTIRE AREA TODAY...AND EXPAND TO ALL OF THE EAST
FOR TONIGHT. PREVIOUS EXPANSION TO FFA LOOKS GOOD. TEMPERATURES SEEM
OK FOR NOW. /08/
&&
.AVIATION...MVFR CONDITIONS IN EAST MS WILL SLOWLY DETERIORATE
THROUGH EARLY AFTERNOON LEAVING WIDESPREAD IFR AT ALL TAF SITES AS
AREAS OF STEADY RAIN PERSIST AND INCREASE. THE RISK OF SCATTERED
TSRA WILL ALSO INCREASE THROUGH 06Z TONIGHT PRODUCING OCCASIONAL
LIFR REPORTS BEFORE TAPERING OFF FROM W TO E FROM 08-12Z TUESDAY.
CONDITIONS SHOULD IMPROVE TO MVFR TUESDAY MORNING 14-18Z WITH RAIN
ENDING AND THEN FINALLY VFR CEILINGS RETURNING DURING THE MIDDLE
AFTERNOON. OVERALL SURFACE WINDS WILL PERSIST ESE AT 10-16KTS TODAY
AND BE VARIABLE TONIGHT BEFORE INCREASING FROM THE NW AT 12-18KTS
EARLY TUESDAY MORNING./40/
&&
.HYDROLOGY...SMALL CONVECTIVE COMPLEXES HAVE BEEN AFFECTING PARTS OF
S MS THIS MORNING...WITH A BAND OF 2 TO 4 INCHES OF RAINFALL HAVING
AFFECTED PARTS OF SE MS AND A FFW HAVING BEEN RECENTLY ISSUED. 88D
RADAR ESTIMATES SEEM PRETTY GOOD IN THOSE AREAS BASED ON GROUND
TRUTH REPORTS...AND ARE PROBABLY SEEING STORM TOTALS IN THE LAST 48
HOURS APPROACHING OR SLIGHTLY EXCEEDING 5 INCHES IN PARTS OF THESE
AREAS. UPPER LOW IS STILL WELL WEST OF THE AREA...AND LATEST
GUIDANCE SUGGESTS SEVERAL WAVES OF MODERATE TO HEAVY RAIN WITH
EMBEDDED CONVECTION AFFECTING MUCH OF THE REGION THROUGH
06Z...POSSIBLY LONGER IN EASTERN SECTIONS. GIVEN SEVERAL WAVES OF
HEAVY RAINFALL OVER THE LAST WEEK HAVING LOWERED ALREADY LIMITED
ABILITY OF WINTER GROUND TO HANDLE HEAVY RAIN...AND SEVERAL RIVERS
NOW APPROACHING OR FORECAST TO EXCEED FLOOD STAGE OVER PARTS OF THE
AREA...HAVE WENT AHEAD AND EXPANDED THE WATCH TO ENCOMPASS THE
ENTIRE REGION. LATEST NAM AND HRRR GUIDANCE SUGGESTS WIDESPREAD
ADDITIONAL 1 TO 2 INCH RAINFALL OVER THE ENTIRE AREA WITH EMBEDDED
BANDS OF 3 TO 5 INCHES WHERE TRAINING OF HEAVIER SHOWERS/STORMS
OCCURS. /08/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 55 43 54 34 / 100 100 3 0
MERIDIAN 57 47 55 31 / 100 100 8 0
VICKSBURG 55 41 54 32 / 100 94 3 0
HATTIESBURG 62 48 58 35 / 100 100 9 0
NATCHEZ 58 42 54 34 / 100 86 3 0
GREENVILLE 51 41 52 33 / 100 100 4 0
GREENWOOD 51 42 52 31 / 100 100 11 0
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...FLOOD WATCH THROUGH MIDNIGHT CST FOR ALL ZONES.
LA...FLOOD WATCH THROUGH MIDNIGHT CST FOR ALL ZONES.
AR...FLOOD WATCH THROUGH MIDNIGHT CST FOR ALL ZONES.
&&
$$
08/JA/15
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
845 AM CST MON DEC 26 2011
...PERIODS OF HEAVY RAIN TODAY WITH QUIETER WEATHER WEEK AHEAD...
.UPDATE...UPDATED TO EXPAND FLOOD WATCH TO ENCOMPASS ENTIRE FORECAST
AREA. MORE IN HYDRO SELECTION BELOW.
&&
.SHORT TERM...TODAY THRU TUESDAY NIGHT
NUMEROUS SHOWERS WITH SOME EMBEDDED THUNDERSTORMS ARE ONGOING THIS
MORNING ACROSS MUCH OF THE ARKLAMISS REGION AS A SMALL SW/V RESOLVED
BY RUC/NAM OUTPUTS AND WEAK ISENTROPIC UPGLIDE AID IN OVERALL LIFT IN
PRESENCE OF NEGATIVE SHOWALTERS. BOTH NMM/ARW SIM REFLECTIVITY DEPICT
THIS ACTIVITY WELL AS IT WILL CONTINUE TO MIGRATE EAST ALONG THE
HWY-84 CORRIDOR THIS MORNING. ISENTROPIC UPGLIDE AND DEEPER
ATMOSPHERIC LIFT WILL ONLY GET BETTER THROUGH THE LATE MORNING AND
ESPECIALLY IN THE AFTN/EVE HOURS AS MAIN MID-LVL CLOSED LOW PHASES
WITH NRN STREAM TROUGH AND PIVOTS ACROSS THE MID-SOUTH LATER TODAY
CAUSING WIDESPREAD SHOWERS/TSRA OVER ALL THE REGION.
INDUCED SFC CYCLOGENESIS WILL OCCUR ACROSS NRN GULF THIS AFTERNOON
AS MID-LVL LOW PIVOTS TOWARDS THE REGION...EFFECTIVELY SURGING
MOISTURE NORTH ON 40-50 KT LOW-LVL JET INTO THE REGION. AMSU SAT
BLENDED WATER PRECIP WATER INDICATES ~1.6 IN PWATS ACROSS SRN
LA/MS...EQUATING TO NEAR 230% OF NORMAL FOR THIS TIME OF YEAR. AS
SUCH...SHOWERS AND EMBEDDED TSRA WILL BE VERY EFFICIENT RAIN
PRODUCERS WITH PROLONGED DURATION POSSIBLE DUE TO TRAINING. AN
EXPANSION OF THE CURRENT FLOOD WATCH FARTHER TO THE SOUTH AND EAST
IS BEING EVALUATED. SEE HYDROLOGY SECTION BELOW FOR MORE DETAILS.
AS STRONG SFC CONVERGENCE COINCIDING WITH GREATEST MOISTURE
TRANSPORT AND VIGOROUS LIFT OCCURS THIS LATE AFTN/NGT...AN UPSWING
IN SHOWER AND TSTORM ACTIVITY LOOKS PROBABLE ACROSS E MS. WHILE NO
STRONG TO SEVERE STORMS ARE EXPECTED GIVEN LACK OF MUCAPE/
SBCAPE...RAINFALL RATES COULD BE ON THE ORDER OF 1-2 INCHES PER HOUR.
FROPA WILL DRIVE THROUGH REGION QUICKLY LATE TONIGHT INTO EARLY
TUESDAY MORNING...ENDING THE MODERATE TO HEAVY RAIN/TSRA ACTIVITY.
DRIZZLE/MIST WILL BE POSSIBLE THROUGH MID-TUESDAY MORNING BEFORE
GRADUAL CLEARING TAKES PLACE ACROSS S/W AREAS TUESDAY AFTERNOON.
FOR FORECAST MATTERS...BLENDED MAV/MET GUIDANCE FOR HIGHS TODAY AS
MAV WAS QUITE WARM IN SEVERAL AREAS AND MET SEEMINGLY NOT CAPTURING
THE MOISTURE RETURN IN OTHERS. FOR TUESDAY...DROPPED HIGHS A COUPLE
OF DEGREES GIVEN CAA...AND FORECAST MIXING HEIGHTS ~3 KFT EQUATING
TO LOWER TO MID 50S GIVEN TEMP PROFILE. /ALLEN/
.LONG TERM...WEDNESDAY THROUGH MONDAY...SURFACE HIGH PRESSURE
RIDGING WILL MOVE OVER THE AREA ON WEDNESDAY WITH LIGHT SOUTHERLY
FLOW DEVELOPING BY LATE AFTERNOON. THE WARMING TREND WILL BEGIN ON
WEDNESDAY WITH HIGH TEMPS WARMING A BIT INTO THE MID TO UPPER 50S FOR
THE MOST PART. SOUTHERLY FLOW WILL CONTINUE TO INCREASE ON THURSDAY
AS HIGH PRESSURE SHIFTS TO THE EAST AND TEMPS WARM INTO THE LOW 60S.
A NICE BEGINNING TO THE NEW YEARS WEEKEND LOOKS ON TRACK FOR FRIDAY
WITH CONTINUED WARM TEMPS AND PARTLY CLOUDY SKIES. THE GLOBAL MODELS
INDICATE THAT AN UPPER TROUGH WILL PASS TO THE NORTH DRAGGING A WEAK
COLD FRONT ACROSS THE AREA FRIDAY NIGHT...BUT THE NICE WEATHER WILL
CONTINUE ON NEW YEARS EVE WITH HIGHS CLIMBING WELL INTO THE 60S. THE
GFS AND ECMWF DIVERGE ON THERE SOLUTIONS AS WE PASS THROUGH THE NEW
YEAR ON SATURDAY NIGHT AND SUNDAY. BOTH OF THE MODELS INDICATE AN
INCREASE IN MOISTURE SATURDAY NIGHT INTO SUNDAY...WITH THE EURO
INDICATING A VIGOROUS UPPER TROUGH PASSING THROUGH THE AREA WITH
SEVERE POSSIBLE ON SUNDAY AND THE GFS FURTHER EAST WITH THE
DEEPENING TROUGH AND MAINLY INDICATING COLD FRONTAL PASSAGE AND JUST
SOME SHOWERS. THE GFS/ECMWF HAVE BEEN FLIP-FLOPPING WITH THIS
SCENARIO OVER THE PAST FEW DAYS SO WILL CONTINUE TO HOLD OFF ON
MENTIONING ANY SEVERE IN THE HWO. COOLER/DRIER CONDITIONS WILL
RETURN ON MONDAY EITHER WAY.
STUCK PRETTY CLOSE TO GUIDANCE TEMPS/POPS THROUGH THE PERIOD...BUT
DID WARM TEMPS SLIGHTLY ABOVE GUIDANCE ON FRIDAY/SATURDAY AND ALSO
BUMPED UP POPS TO INDICATE CHANCE THUNDERSTORMS ON SUNDAY./15/
&&
.AVIATION...MIXTURE OF VFR CONDITIONS ACROSS NRN TAF SITES
KGTR/KGLH/KGTR WITH IFR/LIFR CONDITIONS ACROSS CNTRL/SRN TAF
LOCATIONS. WIDESPREAD RA/TSRA IS ONGOING ACROSS CNTRL/SRN AREAS AT
THIS TIME AND WILL CONTINUE THROUGH REST OF DAY. NRN SITES WILL
RETURN TO MVFR TO IFR THIS MORNING AS RA/TSRA MOVES IN. GREATER
COVERAGE AND INTENSITY OF RA/TSRA THIS AFTERNOON WILL REDUCE VIS
DOWN TO 1-2 SM AT TIMES WITH CIGS 200-500 FT. SFC WINDS WILL VEER
FROM E TO S THROUGH THE DAY WITH QUICK SHIFT TO WEST FOLLOWING FROPA
06-12Z TUESDAY. WINDS SHEAR AND SPEEDS WITH HEIGHT WILL BE ELEVATED
THIS AFTN/NIGHT..ESPECIALLY ACROSS CNTRL/ERN TAF SITES...AMPLIFYING
TURBULENCE IN THE LOWEST 10 KFT. /ALLEN/
&&
.HYDROLOGY...SMALL CONVECTIVE COMPLEXES HAVE BEEN AFFECTING PARTS OF
S MS THIS MORNING...WITH A BAND OF 2 TO 4 INCHES OF RAINFALL HAVING
AFFECTED PARTS OF SE MS AND A FFW HAVING BEEN RECENTLY ISSUED. 88D
RADAR ESTIMATES SEEM PRETTY GOOD IN THOSE AREAS BASED ON GROUND
TRUTH REPORTS...AND ARE PROBABLY SEEING STORM TOTALS IN THE LAST 48
HOURS APPROACHING OR SLIGHTLY EXCEEDING 5 INCHES IN PARTS OF THESE
AREAS. UPPER LOW IS STILL WELL WEST OF THE AREA...AND LATEST
GUIDANCE SUGGESTS SEVERAL WAVES OF MODERATE TO HEAVY RAIN WITH
EMBEDDED CONVECTION AFFECTING MUCH OF THE REGION THROUGH
06Z...POSSIBLY LONGER IN EASTERN SECTIONS. GIVEN SEVERAL WAVES OF
HEAVY RAINFALL OVER THE LAST WEEK HAVING LOWERED ALREADY LIMITED
ABILITY OF WINTER GROUND TO HANDLE HEAVY RAIN...AND SEVERAL RIVERS
NOW APPROACHING OR FORECAST TO EXCEED FLOOD STAGE OVER PARTS OF THE
AREA...HAVE WENT AHEAD AND EXPANDED THE WATCH TO ENCOMPASS THE
ENTIRE REGION. LATEST NAM AND HRRR GUIDANCE SUGGESTS WIDESPREAD
ADDITIONAL 1 TO 2 INCH RAINFALL OVER THE ENTIRE AREA WITH EMBEDDED
BANDS OF 3 TO 5 INCHES WHERE TRAINING OF HEAVIER SHOWERS/STORMS
OCCURS. /08/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 55 43 54 34 / 100 100 3 0
MERIDIAN 57 47 55 31 / 100 100 8 0
VICKSBURG 55 41 54 32 / 100 94 3 0
HATTIESBURG 62 48 58 35 / 100 100 9 0
NATCHEZ 58 42 54 34 / 100 86 3 0
GREENVILLE 51 41 52 33 / 100 100 4 0
GREENWOOD 51 42 52 31 / 100 100 11 0
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...FLOOD WATCH THROUGH MIDNIGHT CST FOR ALL ZONES.
LA...FLOOD WATCH THROUGH MIDNIGHT CST FOR ALL ZONES.
AR...FLOOD WATCH THROUGH MIDNIGHT CST FOR ALL ZONES.
&&
$$
08/JA/15
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
240 PM CST MON DEC 26 2011
.DISCUSSION...
/240 PM CST MON DEC 26 2011/
RAIN IS OVERSPREADING THE AREA FROM THE SOUTH...MORE OR LESS ON TIME
THIS AFTERNOON. HAVE HAD A FEW REPORTS OF A LITTLE SLEET MIXED IN
WITH THE RAIN...BUT THE SLEET IS MELTING VERY QUICKLY AND SHOULD
HAVE NO IMPACT. THE MAIN SLUG OF MOISTURE IS JUST MOVING UP INTO
SOUTHERN MISSOURI FROM ARKANSAS AND LIKELY TO CATEGORICAL POPS STILL
LOOK VERY GOOD FOR MUCH OF EASTERN MISSOURI AND SOUTHERN ILLINOIS.
HOWEVER...LATEST GUIDANCE CONTINUES TO LOOK IFFY FOR MUCH SNOW.
TOP-DOWN METHOD ON BUFKIT SOUNDINGS FROM THE NAM...GFS...LOCAL
WRF...AND THE RUC SHOW THAT BY THE TIME THE LOWER ATMOSPHERE COOLS
ENOUGH TO SUPPORT SNOW...THE TROF WILL BE LIFTING OUT AND AWAY FROM
THE REGION AND DRY AIR WILL BE POURING IN ALOFT. CAN`T ENTIRELY
RULE OUT SNOW SINCE TIMING THE DRY AND COLD AIR WILL BE
CRITICAL...BUT HAVE REDUCED ACCUMULATIONS BELOW 1 INCH...AND HAVE
CHANGED WORDING FROM LIKELY TO CATEGORICAL RAIN/SNOW...TO RAIN AND A
CHANCE OF SNOW.
CARNEY
SRN STORM SYSTEM WILL BE NEARLY BY THE FA BY TUESDAY MORNING...AND
BY THIS TIME...WILL BE AN OPEN WAVE. CONSIDERING HOW THERE IS NOT
MUCH COLD AIR WITH THIS SYSTEM TO BEGIN WITH (N.B. COLD AIR HAS BEEN
HARD TO COME BY SO FAR THIS LATE AUTUMN AND WINTER) AND SFC TEMPS
WILL BE IN THE MID 30S...SNOW AS A GENERAL RULE WILL BE HARD TO COME
BY. MODEL SOUNDINGS FROM ALL GUIDANCE SUGGESTS THIS AS WELL...
ALTHOUGH WBZ VALUES AT ITS LOWEST POINT EARLY TUESDAY MORNING WILL
NOT BE TOO FAR OFF FROM BEING ABLE TO RESULT IN SNOW. SO FOR THIS
REASON...TO INCORPORATE A SMALL AMOUNT OF POTENTIAL MODEL ERROR...
HAVE RETAINED MENTION OF SNOW...BUT AS A MIX WITH RAIN THROUGHOUT
THE CONCLUSION OF THIS EVENT. ANY ADDITIONAL SNOW AMOUNTS TUESDAY
MORNING WILL BE A DUSTING OR LESS AS IT LOOKS AT THIS TIME.
NRN STREAM STORM SYSTEM THAT WILL BE RIGHT ON THE HEELS OF THE SRN
STORM WILL PRODUCE NOTHING MORE THAN SOME ADDITIONAL CLOUDS.
ANOTHER WEAK UPPER LEVEL SYSTEM WILL SLIDE THRU LATE TUESDAY NIGHT
AND WEDNESDAY MORNING BUT WILL CARRY LITTLE MOISTURE WITH IT AND
WILL BE TOO WEAK TO PRODUCE ANY PCPN.
MOS BLENDS LOOK REASONABLE FOR MAX TEMPS TUESDAY AND WEDNESDAY.
WENT AT OR ABOVE THE WARMEST MOS TEMPS FOR MINS WEDNESDAY NIGHT WITH
FAIRLY STOUT SW FLOW THAT SHOULD CARRY INTO A PRETTY MILD DAY ON
THURSDAY AS TEMPS SURGE INTO THE 50S.
A RATHER PROGRESSIVE FLOW WILL DOMINATE THE MEDIUM RANGE FRIDAY THRU
MONDAY AND WILL SIGNAL NO BIG COLD AIR OUTBREAKS (STILL) THRU THE
BEGINNING OF 2012. UPPER LEVEL DISTURBANCES WILL RACE THRU AND EDGE
THE FA LATE FRIDAY AND LATE SATURDAY BUT LIKE THEIR PREDECESSORS
SHOULD BE TOO WEAK TO GENERATE MUCH PCPN THRU SATURDAY. BY EARLY
NEXT WEEK...MOST MODELS TAKE A MUCH STRONGER SYSTEM INTO THE AREA.
THE GFS IS THE EXCEPTION KEEPING THIS SYSTEM WELL TO THE N. HAVE
SLIGHT CHC POPS FOR NOW UNTIL WE CAN GET SOME BETTER RUN-TO-RUN
CONSISTENCY. TEMPS WILL BE AT OR ABOVE AVERAGE THRU THE PERIOD.
TES
&&
.AVIATION...
/1128 AM CST MON DEC 26 2011/
VFR FLIGHT CONDITIONS WILL ACROSS THE AREA FOR MUCH OF THE REST OF
THE AFTERNOON. THERE WILL BE OCCASIONAL SPRINKLES OR LIGHT RAIN
ACROSS PARTS OF SOUTHEAST AND CENTRAL MISSOURI...BUT MOST OF THE
REST OF THE ARE SHOULD REMAIN DRY. CIGS WILL LIKELY DROP BELOW VFR
LATE THIS AFTERNOON/EARLY THIS EVENING ACROSS SOUTHEAST AND EAST
CENTRAL MISSOURI AS WELL AS SOUTHERN ILLINOIS. RAIN WILL BECOME
STEADIER AND HEAVIER...POTENTIALLY MIXING WITH SNOW OVERNIGHT. IFR
CIGS/VSBYS WILL BE LIKELY IN THESE AREAS ESPECIALLY WHERE SNOW
MIXES IN. MOST LIKELY AREAS TO RECEIVE SNOW WILL BE ACROSS THE
EASTERN OZARKS AND SOUTHERN ILLINOIS. SYSTEM WILL BE MOVING RAPIDLY
AWAY FROM THE AREA ON TUESDAY AND LOW CIGS SHOULD CLEAR OUT BY
MID-LATE MORNING. WIND WILL INCREASE FROM THE NORTHWEST...COULD
SEE GUSTS TO 25-30KTS BY 18Z.
SPECIFICS FOR KSTL...VFR FLIGHT CONDITIONS WITH THE POTENTIAL FOR
A FEW SPRINKLES WILL PREVAIL THIS AFTERNOON. EXPECT CIGS TO DROP
RAPIDLY SOMETIME BETWEEN 02Z AND 05Z AS THE STORM SYSTEM TO OUR
SOUTHWEST MOVES INTO THE MISSISSIPPI VALLEY. LATEST MODEL GUIDANCE
IS NOT VERY FAVORABLE FOR MUCH SNOW AT LAMBERT FOR THE DURATION OF
THE STORM...BUT AM RELUCTANT TO PULL ALL MENTION OF SNOW AT THIS
TIME AS MANY INDICATORS ARE VERY CLOSE. SHOULD SEE PRECIP END
BEFORE 12Z TUESDAY WITH INCREASING WINDS FROM THE NORTHWEST BEHIND
THE SYSTEM. WIND MAY GUST UP TO 25-30KTS DURING THE AFTERNOON.
CARNEY
&&
.PRELIMINARY POINT TEMPS/POPS...
ST LOUIS 35 44 28 45 / 90 30 0 0
QUINCY 31 40 26 43 / 30 5 0 0
COLUMBIA 31 44 27 46 / 40 5 0 0
JEFFERSON CITY 32 44 27 46 / 60 5 0 0
SALEM 34 42 24 41 / 100 80 0 0
FARMINGTON 33 44 24 45 / 100 30 0 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
424 PM EST MON DEC 26 2011
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL RAPIDLY MOVE OFF THE EAST COAST
TONIGHT ALLOWING FOR A SOUTHERLY FLOW OF MILDER AIR TO DEVELOP
OVER THE REGION LATER TONIGHT AND TUESDAY. WITH MILDER AIR IN
PLACE...MAINLY RAIN WILL FALL ACROSS THE REGION TUESDAY AFTERNOON
AND EVENING AS A STORM SYSTEM TRACKS NORTHEAST THROUGH
PENNSYLVANIA AND NEW YORK. AFTER THIS STORM PASSES TO THE
NORTHEAST TUESDAY NIGHT COLDER AIR WILL RETURN TO THE REGION
CHANGING THE RAIN TO SNOW AND SNOW SHOWERS. MOST OF THE REGION
WILL SEE LITTLE SNOW ACCUMULATION...EXCEPT FOR NORTH CENTRAL NEW
YORK WHERE A FEW INCHES IS POSSIBLE BY WEDNESDAY AFTERNOON.
&&
.NEAR TERM /THROUGH TUESDAY/...
VIS SATL IMAGERY SHOWS SC LAYER OVER ALL OF C NY AND NE PA. LARGE
SCALE SUBSC BEHIND DEPARTING SHRT WAVE OFF THE NE COAST WILL CONT
TO PUSH INVERSION DOWN AND EVENTUALLY WILL LEAD TO CLRG SKIES
LATE THIS AFTERNOON AND ERLY EVENING. VIS SATL IMAGERY ALREADY
SHOWG THIS IN WRN NY AND NC/NE PA. THE BACK EDGE OF THE SC LAYER
CORRELATED WELL WITH THE 850 MB TEMP GRADIENT WHICH IS INDICATIVE
OF THE SUBSC. USING THE LOCAL WRFARW...THIS GRADIENT MOVES THRU
BTWN 21Z AND 00Z...WHILE THE RUC13 HOLDS ONTO THE COLDER H85 TEMPS
IN EC NY A LITTLE LONGER. IN ANY EVENT BOTH SEEM TO SHOW SIGNS
THAT THIS CLRG WILL TAKE A BIT LONGER IN EC NY...WHERE THERE IS
HIGHER TERRAIN. THIS MAKES SENSE AND WILL HOLD ONTO CLDS A LITTLE
LONGER IN THESE AREAS. REST OF AREA SEES CLRG FOR A TIME THIS
EVENING.
AFTER THE CLDS CLEAR OUT THIS EVENING...HIGHER CLDS FROM THE NEXT
SYSTEM BEGIN TO SPREAD ACROSS NY AND PA. THE SFC RDG AXIS IS E OF
THE REGION TONIGHT AS THE NEXT SYSTEM RAPIDLY APPRCHES FROM THE
SRN PLAINS AND UPR MIDWEST. THE LL FLO WILL TURN SWRLY AND SHUD
KEEP TEMPS FROM BOTTOMING OUT MUCH BELOW 30 MOST PLACES. THE
EXCEPTION IS IN NE PA/SERN NY WHERE THE WINDS WILL REMAIN LIGHT
ENUF WITH CLR SKIES. THUS MINS WILL BE HIGHER IN THE NW CWA LOW
30S AND LOWER IN THE SE CWA MID TO UPPER 20S OR SO.
FOR TUESDAY...CLDS WILL INCREASE THRU THE DAY AS STRG WAA/ISEN
LIFT TAKES PLACE THRU A DEEPER AND DEEPER LAYER AS THE DAY
PROGRESSES. TEMPS FROM THE SFC THRU 850 MB WILL BE WARM ENUF FOR
ALL RAIN ENTIRE CWA. ALL SYNOPTIC SCALE MODELS INDICATE THAT THE
RAIN WILL MOVE IN DURING THE AFTERNOON. WILL RAMP POPS UP BTWN 18Z
TUE AND 00Z WED.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
THE 12Z EURO...18Z NAM...12Z GFS HAVE TRENDED MORE TOWARD THE WEST
WITH THE SFC LO AND ALL INDICATE THAT THE 850 MB LOW TRACKS TO WRN
NY BY 00Z WED. THIS WILL ALLOW 850 MB TEMPS TO CLIMB WELL ABV FRZG
AS THE PRECIP WORKS IN. WITH BNDRY LAYER TEMPS EXPECTED ABV
FRZG...PRECIP WILL BE MAINLY RAIN AT THE ONSET. IN ADDTN...WITH
THIS MORE WRN TRACK...THE DRY SLOT WITH THE DEVELOPING CYCLONE
MOVES RIGHT THRU NE PA AND C NY TUE EVE. COLDER AIR DOES NOT SURGE
IN UNTIL THE BULK OF THE MOISTURE AND LIFT WITH THE STORM IS NE OF
OUR AREA. THUS...IT LOOKS LIKE A RAIN EVENT...POSSIBLY MIXED WITH
SLEET/SNOW FINGER LAKES/UPR MOHAWK/TUG HILL TUE EVE...THEN WRAP
AROUND SNOW AND SNOW SHOWERS ENHANCED BY MOISTURE FROM LAKE
ONTARIO TUE NGT/ERLY WED.
THE SNOW SHOWERS WILL CONT WED IN C NY AS THE WRAP AROUND SNOW
SHOWERS TRANSITIONS TO LAKE EFFECT SNOWS. THE INVERSION RAPIDLY
DROPS DOWN TO 900 MB BY 00Z THU. THUS THERE WILL BE SOME LES...BUT
IT SHUD NOT BE A MAJOR EVENT. MOST OF THE SNOW WILL FALL WED
AM...IN NC NY WITH THE COMBINATION OF LAKE EFFECT AND SYNOPTIC
MOISTURE.
SEE 2-5 INCHES OF SNOW IN NC NY...WITH AN INCH OR LESS SC NY/FAR
NRN PA AND LITTLE IF ANY IN THE REST OF NE PA.
ANOTHER CONCERN IS THE POTENTIAL FOR HIGH WINDS ON WEDNESDAY AS
THE DEEPENING CYCLONE DEPARTS ACRS LWR QUEBEC. MOS GUIDC SUGGESTS
LOW END WIND ADVY CRITERIA. ISALLABORIC PRESSURE RISES ARE RUNNING
CLOSE TO 10 MB/6 HR WHICH IS ALSO BORDERLINE FOR WIND ADVY. SO
WILL HIGHLIGHT IN HWO FOR ENTIRE CWA...AND WILL HIGH POTENTIAL FOR
SOME SNOW IN NC NY AS WELL.
BY WED NGT...LES SNOW SHOWERS AND FLURRIES RAPIDLY COME TO AN END
AS THE LL FLO TURNS MORE WRLY IN ADVANCE OF THE NEXT SYSTEM.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
THE LONG TERM WILL BE DOMINATED BY A BRISK WEST TO EAST FLOW, AS
THE STRONGLY POSITIVE PNA PATTERN RELAXES. THE RESULT WILL BE A
SERIES OF CLIPPERS AND FAST MOVING SYSTEMS TRAVERSING THE GREAT
LAKES AND SOUTHERN ONTARIO PROVINCE.
HOWEVER BY LATE IN THE PERIOD, A JET WILL DIVE INTO THE PLAINS AND
CARVE OUT ANOTHER DEEP TROUGH OVER THE WEST-CENTRAL UNITED STATES.
THIS WILL CAUSE THE POSITIVE PNA PATTERN TO BEGIN TO STRENGTHEN
AGAIN, WITH RISING HEIGHTS INTO THE EASTERN CONUS.
AS A RESULT, WE ARE FORECASTING LOW POP, BRIEF DURATION RW/SW
EVENTS WITH LITTLE ACCUMULATION ANTICIPATED. WE ARE ALSO
FORECASTING TEMPERATURES SLIGHTLY ABOVE NORMAL FOR THE THURSDAY TO
MONDAY PERIOD.
&&
.AVIATION /21Z MONDAY THROUGH SATURDAY/...
MODELS ALL SHOW THE CEILING BREAKING UP OVER THE NEXT 3 HOURS AS
DRY AIR UNDERCUTS THE INVERSION. TEMPO MVFR CONDITIONS WILL
PERSIST FOR THE NEXT FEW HOURS AT BGM AND ITH, THEN QUICKLY RISE
TO VFR.
IT WILL BE A QUIET OVERNIGHT WITH LIGHT WINDS AND CIRRUS OVERHEAD.
PRECIPITATION AHEAD OF AN ADVANCING STORM SYSTEM MAY REACH THE AVP
TERMINAL BETWEEN 17Z AND 20Z ON TUESDAY. AT THIS POINT WE ARE NOT
CONFIDENT ENOUGH OF THE ONSET TIME TO PUT IT IN THE CURRENT TAF
PACKAGE. THE 0Z PACKAGE WILL CONTAIN FORECAST PRECIP START TIMES
FOR ALL TERMINALS.
.OUTLOOK...
TUE MORN...VFR.
TUE AFTN/TUE NGT/WED MORN...MVFR IN RAIN DROPPING TO IFR IN SNOW
SHOWERS TUESDAY NIGHT.
WED AFTN/THU...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...DJP
AVIATION...DJP
AREA FORECAST DISCUSSION
NWS BUFFALO NY
345 PM EST MON DEC 26 2011
.SYNOPSIS...
HIGH PRESSURE CENTERED OVER VIRGINIA THIS EVENING WILL DRIFT OFF THE
MID ATLANTIC COAST OVERNIGHT. A COMPLEX DOUBLE BARRELLED STORM
SYSTEM STRETCHING FROM THE UPPER GREAT LAKES TO THE TENNESSEE VALLEY
WILL THEN DEVELOP A CONSOLIDATED AREA OF LOW PRESSURE OVER
PENNSYLVANIA LATE TUESDAY. THIS STORM SYSTEM IS FORECAST TO LIFT TO
THE SAINT LAWRENCE VALLEY BY WEDNESDAY MORNING. THIS SCENARIO WILL
LEAD TO RAIN AND MIXED PRECIPITATION ACROSS OUR REGION ON TUESDAY...
WITH COLDER AIR ON THE BACKSIDE OF THE STORM CHANGING ALL OF THE
PRECIPITATION TO ACCUMULATING SNOW LATE TUESDAY AND TUESDAY NIGHT.
&&
.NEAR TERM /THROUGH TUESDAY/...
IT WILL BE A VERY PLEASANT EARLY WINTER EVENING ACROSS THE FORECAST
AREA AS SFC HIGH PRESSURE NOSING NORTH FROM VIRGINIA WILL RESULT IN
CLEAR TO PARTLY CLOUDY SKIES. THIS SHOULD ALLOW FOR DECENT VIEWING
OF VENUS IN THE SOUTHWESTERN SKY AND JUPITER TO THE SOUTHEAST. SKIES
WILL BECOME INCREASINGLY CLOUDY DURING THE OVERNIGHT THOUGH...AS
CIRRUS WILL STREAM NORTHWARDS AHEAD OF A PHASING SPLIT UPPER LEVEL
FLOW.
WV IMAGERY FROM LATE IN THE AFTERNOON SHOWS TWO DISTINCT SHORTWAVES
CHUGGING TO THE EAST. THE NORTHERN BRANCH FEATURE WAS OVER THE UPPER
MISSISSIPPI VALLEY WHILE THE SOUTHERN BRANCH VORT CENTER WAS
APPROACHING THE LOWER MISSISSIPPI VALLEY. THE DEVELOPING SOUTHERLY
FLOW BETWEEN THESE TWIN FEATURES AND THE EXITING HIGH PRESSURE WILL
CIRCULATE THE INCREASED MOISTURE NORTHWARDS...WHILE ALSO DEVELOPING
A WARM ADVECTIVE PATTERN. THIS SCENARIO WILL ALSO HELP TO HOLD UP
OUR TEMPERATURES OVERNIGHT...SO THAT INSTEAD OF DROPPING TO OUR LATE
AFTERNOON DEW POINT TEMPS (LOW-MID 20S)...MOST AREAS WILL ONLY
BOTTOM OUT IN THE UPPER 20S TO LOWER 30S. SITES EAST OF LK ONTARIO
WILL BE A BIT COLDER. THESE READINGS WILL BE SOME 10 DEG F ABOVE
SEASONAL NORMALS.
THE TWIN VORTICES WILL CONVERGE ON THE UPPER OHIO VALLEY DURING THE
DAY TUESDAY WHILE LOW PRESSURE WILL CONSOLIDATE IN THE VCNTY OF
EASTERN OHIO AND WESTERN PENNSYLVANIA. WHILE THIS WILL INITIALLY
KEEP A SOUTHERLY WARM ADVECTIVE FLOW OVER ALL OF OUR FORECAST
AREA...THE MID LEVEL WARMTH WILL GET CUT OFF DURING THE COURSE OF
THE AFTERNOON AS THE CIRCULATION ALOFT (THROUGH 10K FT) IS FORECAST
TO CUT OFF OVER THE WRN COUNTIES. THIS WILL COMPLICATE AN ALREADY
TRICKY FORECAST.
THE DYNAMICS IMPOSED BY A DIVERGENT UPPER LEVEL FLOW AND RR QUAD OF
A 130KT H25 JET WILL PROMOTE WIDESPREAD PCPN ACROSS OUR AREA ON
TUESDAY...WITH THE PRECIPITATION LIFTING NORTHEAST AND SPREADING
ACROSS THE WESTERN COUNTIES DURING THE MORNING AND MIDDAY. AREAS
EAST OF LK ONTARIO SHOULD BE PCPN FREE UNTIL EARLY TO MID AFTERNOON.
WHILE SFC TEMPS WILL RANGE FROM THE UPPER 30S TO LOWER 40S ACROSS
MOST OF WESTERN NEW YORK AT THE ONSET OF THE PCPN...THERMAL PROFILES
FROM BOTH THE NAM AND GFS SUGGEST THAT THE COLUMN WILL BE LARGELY
BELOW FREEZING ABOVE 1500 FT. NOT ONLY IS THE BULK OF THE SOUNDING
FORECAST TO BE BELOW FREEZING...BUT THE LOWEST 5K FT WILL LIKELY BE
ISOTHERMAL BETWEEN MINUS 2 AND MINUS 5C. MORE ON THAT IN A MOMENT.
THIS SOMEWHAT UNUSUAL SOUNDING IS DUE TO A RATHER STRANGE SFC STORM
TRACK...THAT TAKES THE SFC LOW FROM NEAR PIT TO ABOUT BGM THEN TO
BTV. SFC STORMS USUALLY TRACK WEST OR EAST OF THE OROGRAPHIC
(ALLEGANY MTNS)...BUT IN THIS CASE THE LOW IS FORECAST TO TRACK
ACROSS THE TOPOGRAPHY. AS MENTIONED EARLIER...THIS WILL CUT OFF THE
MID LEVEL WARMTH FAIRLY EARLY ON IN THE EVENT SO HAVE LEANED TOWARDS
A `COLDER` FORECAST WITH A FASTER CHANGEOVER TO MIXED/SNOW EVENT.
FOR WHAT ITS WORTH...THE SREF PCPN PLUMES FAVOR THIS SOLUTION AND
ARE IN FAIRLY GOOD AGREEMENT WITH THE FORECAST SOUNDINGS FROM THE
OTHER MAJOR GUIDANCE PACKAGES.
QPF FOR TUESDAY WILL RANGE FROM A QUARTER INCH ACROSS THE SRN TIER
TO A LITLE MORE THAN A TENTH ELSEWHERE. THIS IS NOT SIGNIFICANT FOR
THE DAYLIGHT HOURS...ALTHOUGH THE HIGHER TERRAIN OF THE SOUTHERN
TIER COULD PICK UP A WET INCH OR SO OF ACCUMULATION BY NIGHTFALL.
ONE WORRISOME SUBTLETY IN THE FORECAST SOUNDINGS IS THAT A FAIRLY
DEEP MINUS 2 TO MINUS 5 LAYER ISOTHERMAL LAYER WILL PROMOTE MORE
EFFICIENT SNOW MAKING AS AGGREGATION IN THE LOW LEVELS COULD BE
SIGNIFICANT.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY/...
DEEPENING LOW PRESSURE TRACKING ACROSS NEW ENGLAND WILL BRING IN
COLDER AIR TUESDAY NIGHT...WHICH WILL CHANGE PRECIPITATION OVER TO
SNOW. THIS WILL LIKELY BRING ACCUMULATING SNOW TO ALL OF WESTERN NEW
YORK...WITH THE POSSIBILITY OF MORE SIGNIFICANT (6 INCHES OR GREATER
OF SNOW) ACROSS THE SOUTHERN TIER...AND EAST OF LAKE ONTARIO. MUCH
COLDER AIR WILL MOVE IN WEDNESDAY...WITH LINGERING LAKE EFFECT SNOW
SHOWERS SE OF LAKE ONTARIO...AND BLUSTERY CONDITIONS DURING THE
DAY...WITH WITH HIGHS ON WEDNESDAY ONLY IN THE LOWER 20S ACROSS MUCH
OF THE REGION.
FOR THE DETAILS...MODEL AGREEMENT HAS IMPROVED WITH THE 12Z
RUNS...WITH GENERALLY A FAIRLY TIGHT CLUSTER OF SOLUTIONS AMONG THE
MODELS CONSULTED. THE BIGGEST MATERIAL DIFFERENCE AMONG MODELS IS HOW
QUICKLY THE LOW DEEPENS...WITH THE 12Z NAM TRENDING SLOWER THAN MOST
OTHER MODELS. USING A CONSENSUS OF THE 12Z RUNS OF THE
NAM/RGEM/GFS/UKMET/EUROPEAN/SREF PUTTING 985 MB SURFACE LOW ALONG
THE MAINE/QUEBEC BORDER AT 12Z WEDNESDAY. DESPITE THE FAIRLY GOOD
MODEL AGREEMENT...THE CHALLENGE IN THIS EVENT IS THE DETAILS. BUT
TUESDAY NIGHT...FORECAST SOUNDINGS WILL BE MARGINAL FOR SNOW IN FAR
WESTERN SECTIONS...AND IN JEFFERSON/LEWIS COUNTIES. RAIN/SNOW WILL
DEPEND ON SUBTLE DIFFERENCES IN SURFACE TEMPERATURE...WHERE HIGHER
ELEVATIONS WILL LIKELY CHANGEOVER FIRST.
LATE TUESDAY NIGHT...A STRONG PSEUDO-ARCTIC BOUNDARY WILL SWEEP
ACROSS AS THE LOW INTENSIFIES IN EASTERN QUEBEC. COLD AIR WITH THIS
WILL DEFINITELY CHANGE PRECIPITATION OVER TO SNOW...AND IT IS THIS
FEATURE WHICH WILL LIKELY BRING AN INCH OR TWO ACROSS THE REGION.
ON WEDNESDAY...THIS ARCTIC BOUNDARY WILL CONTINUE TO PUSH TO THE
EAST OF REGION...USHERING IN COLD DAYTIME TEMPS. WITH THE UPPER TROF
STILL BACK ACROSS THE REGION...EXPECT THIS WILL SET UP A BRIEF
PERIOD OF LAKE ENHANCED SNOW SE OF LAKE ONTARIO...WAYNE COUNTY
EASTWARD. WINDS WILL BE A BIT ON THE STRONG SIDE...BUT WITH RAPID
COOLING...LAKE INDUCED INSTABILITY WILL INCREASE TO AROUND 300 J/KG.
AS THE SHORTWAVE EXITS...THIS SHOULD DRY THE AIR OUT...ALLOWING LAKE
SNOWS TO TAPER OFF.
A WINTER STORM WATCH WAS CONSIDERED...BUT ULTIMATELY CONFIDENCE IS
NOT QUITE HIGH ENOUGH FOR THE HEADLINE. SNOW AMOUNTS ARE MARGINAL TO
SUPPORT THE HEADLINE...AND WITH THE SEVERAL CLOSE CALLS WITH THIS
SYSTEM...FROM THE MARGINALLY COLD AIR MASS AT THE ONSET...TO THE
FRONTAL BOUNDARY SNOW SHOWERS...TO THE POSSIBLE LAKE ENHANCEMENT AT
THE END. BECAUSE OF THIS...WILL HOLD OFF ON ANY HEADLINES AND
CONTINUE A MENTION IN THE HWO. FOR THOSE INTERESTED IN SNOW
AMOUNTS...EXPECT MOST LOCATIONS TO BE IN THE 1 TO 3 INCH RANGE. THE
EXCEPTIONS ARE WESTERN PORTIONS OF THE SOUTHERN TIER...AND E-SE OF
LAKE ONTARIO...ROUGHLY INCLUDING WAYNE/N
CAYUGA/OSWEGO/JEFFERSON/LEWIS COUNTIES...WHERE 4 INCHES OR GREATER
OF SNOW ARE LIKELY. DEPENDING ON HOW SEVERAL FACTORS WORK
OUT...COULD SEE AMOUNTS TO 8 INCHES IN SOME OF THESE
LOCATIONS...HOWEVER AMOUNTS THIS HIGH ARE ONLY A POSSIBILITY AT THIS
TIME.
THERE WILL BE OTHER IMPACTS WITH THIS SYSTEM. THE FRONTAL BOUNDARY
WILL CAUSE TEMPERATURES TO DROP QUITE RAPIDLY EARLY WEDNESDAY
MORNING. THIS MAY CAUSE ANY WATER OR SLUSH ON ROADWAYS TO
FREEZE...POTENTIALLY MAKING FOR A SLICK COMMUTE WEDNESDAY MORNING.
ALSO...THE TIMING OF THE FRONTAL BOUNDARY WILL BE KEY...AS EVEN AN
INCH OR TWO OF SNOW CAN BE A NUISANCE...IF IT COMES QUICKLY AND NEAR
RUSH HOUR.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
HIGH PRESSURE WILL BRIEFLY RIDGE ACROSS THE REGION WEDNESDAY NIGHT.
THERE MAY BE SOME LINGERING LAKE EFFECT SNOW SHOWERS EAST OF LAKE
ONTARIO...WITH THIS TO END AS WINDS SHIFT TO THE SW LATE IN THE
NIGHT.
THE THURSDAY THROUGH SUNDAY PERIOD WILL FEATURE A ZONAL FLOW...WITH
A COUPLE OF CLIPPERS FORECAST TO CROSS THE REGION. THE 12Z
GFS/EUROPEAN/GGEM DIFFER ON THE TIMING OF THESE FAST SYSTEM...MAKING
POPS DIFFICULT TO BE TOO SPECIFIC. ALSO...TEMPERATURES WILL BE
MARGINAL FOR LAKE EFFECT AHEAD OF THE CLIPPER. THE RESULT WILL BE
ONLY MODEST LEVELS OF INSTABILITY...AND TEMPERATURES WILL AT TIMES
BE MARGINALLY COLD ENOUGH FOR SNOW...WITH SOME RAIN POSSIBLE. GIVEN
THE MARGINALLY COLD 850MB TEMPS...DO NOT EXPECT ANY MAJOR EVENTS
FROM THESE CLIPPERS...BUT IT WILL BE HARD TO RULE OUT A RAIN OR SNOW
SHOWER DURING THIS PERIOD...EVEN IF THE MAJORITY OF THE TIME WILL BE
DRY. A STALLED FRONTAL BOUNDARY WILL BE CLOSE TO THE EASTERN LAKE
ONTARIO REGION...SO AS THIS FLUCTUATES WITH THE SYSTEMS...IT MAY BE
MARKEDLY COLDER THERE AT TIMES.
ON MONDAY...THE EUROPEAN LIFTS LOW PRESSURE ACROSS THE REGION...WITH
THE GFS/GGEM SHOWING MORE OF A RIDGE. NO STRONG FEELINGS EITHER WAY
ON THIS...AND WILL SIMPLY MAINTAIN CHANCE POPS.
&&
.AVIATION /21Z MONDAY THROUGH SATURDAY/...
VFR CONDITIONS WILL BE IN PLACE TONIGHT INTO AT LEAST THE FIRST
HALF OF TUESDAY...DESPITE AN INCREASE IN HIGH AND MID LEVEL
MOISTURE. THE INCREASED CLOUD COVER WILL BE DUE A DEVELOPING AREA
OF LOW PRESSURE OVER THE UPPER OHIO VALLEY.
CLOUDS FROM THIS STORM SYSTEM WILL LOWER AND THICKEN DURING THE
MIDDAY AND AND AFTERNOON THURSDAY...WITH RAIN (MIXED PCPN HIGHER
ELEVATIONS) LIFTING FROM THE SOUTHWEST CORNER OF THE STATE TO THE
EASTERN LAKE ONTARIO REGION IN THE PROCESS. CIGS BY LATE AFTERNOON
WILL RANGE FROM IFR ACROSS THE WESTERN COUNTIES TO MVFR NEAR KART
AND KGTB.
OUTLOOK...
TUESDAY NIGHT...IFR WITH WIDESPREAD RAIN CHANGING TO WET SNOW.
WEDNESDAY...MVFR WITH MORNING SNOW SHOWERS IMPROVING TO VFR.
THURSDAY...MAINLY VFR.
THURSDAY NIGHT AND FRIDAY...MVFR WITH A CHANCE OF RAIN AND SNOW
SHOWERS.
SATURDAY...VFR.
&&
.MARINE...
HIGH PRESSURE NOSING NORTH FROM VIRGINIA WILL KEEP MODERATE TO FRESH
SOUTHWESTERLIES ACROSS LAKE ERIE AND EASTERN LAKE ONTARIO THROUGH
THIS EVENING SO SMALL CRAFT ADVISORIES WILL REMAIN IN EFFECT FOR
THOSE NEARSHORE WATERS. AS THE NIGHT PROGRESSES...THE FLOW WILL BACK
TO THE SOUTH AND WEAKEN. THIS WILL ALLOW WAVES TO SUBSIDE A BIT
WHILE MORE IMPORTANTLY PUSHING THE HIGHEST WAVES TO CANADIAN WATERS.
A STORM SYSTEM WILL DEVELOP OVER THE MID WEST ON TUESDAY AND
APPROACH THE LOWER GREAT LAKES DURING THE AFTERNOON AND EVENING. THIS
WILL ACTUALLY WEAKEN THE SFC PRESSURE GRADIENT IN THIS CASE SO THAT
WINDS AND WAVES SHOULD BE BELOW SCA CRITERIA. AS THE SYSTEM MOVES TO
THE SAINT LAWRENCE VALLEY AND STRENGTHENS TUESDAY NIGHT...STRONG
NORTHWEST WINDS WILL DEVELOP ACROSS LAKE ERIE...AND BY DAYBREAK
WEDNESDAY...ACROSS LAKE ONTARIO. DEFINITE SCA CONDITIONS WILL BE IN
PLACE AT THAT TIME...WITH THE THREAT OF GALE FORCE WINDS.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LEZ040-
041.
SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
LOZ043-044.
SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR LOZ045.
&&
$$
SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...APFFEL
LONG TERM...APFFEL
AVIATION...RSH
MARINE...RSH
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
343 PM EST MON DEC 26 2011
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL RAPIDLY MOVE OFF THE EAST COAST
TONIGHT ALLOWING FOR A SOUTHERLY FLOW OF MILDER AIR TO DEVELOP
OVER THE REGION LATER TONIGHT AND TUESDAY. WITH MILDER AIR IN
PLACE...MAINLY RAIN WILL FALL ACROSS THE REGION TUESDAY AFTERNOON
AND EVENING AS A STORM SYSTEM TRACKS NORTHEAST THROUGH
PENNSYLVANIA AND NEW YORK. AFTER THIS STORM PASSES TO THE
NORTHEAST TUESDAY NIGHT COLDER AIR WILL RETURN TO THE REGION
CHANGING THE RAIN TO SNOW AND SNOW SHOWERS. MOST OF THE REGION
WILL SEE LITTLE SNOW ACCUMULATION...EXCEPT FOR NORTH CENTRAL NEW
YORK WHERE A FEW INCHES IS POSSIBLE BY WEDNESDAY AFTERNOON.
&&
.NEAR TERM /THROUGH TUESDAY/...
VIS SATL IMAGERY SHOWS SC LAYER OVER ALL OF C NY AND NE PA. LARGE
SCALE SUBSC BEHIND DEPARTING SHRT WAVE OFF THE NE COAST WILL CONT
TO PUSH INVERSION DOWN AND EVENTUALLY WILL LEAD TO CLRG SKIES
LATE THIS AFTERNOON AND ERLY EVENING. VIS SATL IMAGERY ALREADY
SHOWG THIS IN WRN NY AND NC/NE PA. THE BACK EDGE OF THE SC LAYER
CORRELATED WELL WITH THE 850 MB TEMP GRADIENT WHICH IS INDICATIVE
OF THE SUBSC. USING THE LOCAL WRFARW...THIS GRADIENT MOVES THRU
BTWN 21Z AND 00Z...WHILE THE RUC13 HOLDS ONTO THE COLDER H85 TEMPS
IN EC NY A LITTLE LONGER. IN ANY EVENT BOTH SEEM TO SHOW SIGNS
THAT THIS CLRG WILL TAKE A BIT LONGER IN EC NY...WHERE THERE IS
HIGHER TERRAIN. THIS MAKES SENSE AND WILL HOLD ONTO CLDS A LITTLE
LONGER IN THESE AREAS. REST OF AREA SEES CLRG FOR A TIME THIS
EVENING.
AFTER THE CLDS CLEAR OUT THIS EVENING...HIGHER CLDS FROM THE NEXT
SYSTEM BEGIN TO SPREAD ACROSS NY AND PA. THE SFC RDG AXIS IS E OF
THE REGION TONIGHT AS THE NEXT SYSTEM RAPIDLY APPRCHES FROM THE
SRN PLAINS AND UPR MIDWEST. THE LL FLO WILL TURN SWRLY AND SHUD
KEEP TEMPS FROM BOTTOMING OUT MUCH BELOW 30 MOST PLACES. THE
EXCEPTION IS IN NE PA/SERN NY WHERE THE WINDS WILL REMAIN LIGHT
ENUF WITH CLR SKIES. THUS MINS WILL BE HIGHER IN THE NW CWA LOW
30S AND LOWER IN THE SE CWA MID TO UPPER 20S OR SO.
FOR TUESDAY...CLDS WILL INCREASE THRU THE DAY AS STRG WAA/ISEN
LIFT TAKES PLACE THRU A DEEPER AND DEEPER LAYER AS THE DAY
PROGRESSES. TEMPS FROM THE SFC THRU 850 MB WILL BE WARM ENUF FOR
ALL RAIN ENTIRE CWA. ALL SYNOPTIC SCALE MODELS INDICATE THAT THE
RAIN WILL MOVE IN DURING THE AFTERNOON. WILL RAMP POPS UP BTWN 18Z
TUE AND 00Z WED.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
THE 12Z EURO...18Z NAM...12Z GFS HAVE TRENDED MORE TOWARD THE WEST
WITH THE SFC LO AND ALL INDICATE THAT THE 850 MB LOW TRACKS TO WRN
NY BY 00Z WED. THIS WILL ALLOW 850 MB TEMPS TO CLIMB WELL ABV FRZG
AS THE PRECIP WORKS IN. WITH BNDRY LAYER TEMPS EXPECTED ABV
FRZG...PRECIP WILL BE MAINLY RAIN AT THE ONSET. IN ADDTN...WITH
THIS MORE WRN TRACK...THE DRY SLOT WITH THE DEVELOPING CYCLONE
MOVES RIGHT THRU NE PA AND C NY TUE EVE. COLDER AIR DOES NOT SURGE
IN UNTIL THE BULK OF THE MOISTURE AND LIFT WITH THE STORM IS NE OF
OUR AREA. THUS...IT LOOKS LIKE A RAIN EVENT...POSSIBLY MIXED WITH
SLEET/SNOW FINGER LAKES/UPR MOHAWK/TUG HILL TUE EVE...THEN WRAP
AROUND SNOW AND SNOW SHOWERS ENHANCED BY MOISTURE FROM LAKE
ONTARIO TUE NGT/ERLY WED.
THE SNOW SHOWERS WILL CONT WED IN C NY AS THE WRAP AROUND SNOW
SHOWERS TRANSITIONS TO LAKE EFFECT SNOWS. THE INVERSION RAPIDLY
DROPS DOWN TO 900 MB BY 00Z THU. THUS THERE WILL BE SOME LES...BUT
IT SHUD NOT BE A MAJOR EVENT. MOST OF THE SNOW WILL FALL WED
AM...IN NC NY WITH THE COMBINATION OF LAKE EFFECT AND SYNOPTIC
MOISTURE.
SEE 2-5 INCHES OF SNOW IN NC NY...WITH AN INCH OR LESS SC NY/FAR
NRN PA AND LITTLE IF ANY IN THE REST OF NE PA.
ANOTHER CONCERN IS THE POTENTIAL FOR HIGH WINDS ON WEDNESDAY AS
THE DEEPENING CYCLONE DEPARTS ACRS LWR QUEBEC. MOS GUIDC SUGGESTS
LOW END WIND ADVY CRITERIA. ISALLABORIC PRESSURE RISES ARE RUNNING
CLOSE TO 10 MB/6 HR WHICH IS ALSO BORDERLINE FOR WIND ADVY. SO
WILL HIGHLIGHT IN HWO FOR ENTIRE CWA...AND WILL HIGH POTENTIAL FOR
SOME SNOW IN NC NY AS WELL.
BY WED NGT...LES SNOW SHOWERS AND FLURRIES RAPIDLY COME TO AN END
AS THE LL FLO TURNS MORE WRLY IN ADVANCE OF THE NEXT SYSTEM.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
330 AM UPDATE...
LITTLE CHANGE. UNSETTLED WITH MULTIPLE STORMS. LAKE EFFECT
THURSDAY. A STORM FROM THE WEST FRIDAY FOLLOWED BY ANOTHER
SATURDAY THEN A THIRD ON MONDAY. COULD BE MIXED PRECIP ACROSS NE
PA AND SULLIVAN NY WITH 850MB TEMPS JUST BELOW ZERO AND
THICKNESSES ALSO ON THE EDGE. GIVEN WEST TO EAST STORM TRACK AND
LACK OF COLD AIR NOT EXPECTING ANY BIG SNOW STORMS.
4 PM SUNDAY UPDATE...
MODELS IN AGREEMENT FOR WEDNESDAY NIGHT, WITH HIGH PRESSURE OVER THE
AREA AND GENERALLY QUIET WEATHER UNTIL EARLY FRIDAY MORNING. THE
EXCEPTION MAY BE SOME WEAK LES WEDNESDAY NIGHT.
BY FRIDAY MORNING THE MODELS BEGIN TO DISAGREE. IT SEEMS AS THOUGH
TIMING MAY BE THE LARGER ISSUE. BY 12Z FRIDAY, THE GFS HAS A SFC
LOW OVER LAKE MICHIGAN, WITH PRECIP WELL OUT TO THE EAST. THE
ECMWF HAS TWO SEPARATE LOWS. ONE OVER THE GEORGIA BAY AND ONE OVER
SOUTH DAKOTA. BOTH ARE MUCH WEAKER THAN THE LOW IN THE GFS. BY 00Z
SAT THE GFS HAS THE LOW JUST TO THE NORTH OF LAKE ONTARIO AND THE
ECMWF KICKS OUT THE INITIAL LOW AND HAS THE SECOND LOW ABOUT THE
SAME PLACE THE GFS HAD THE LOW 12 HOURS EARLIER. THE ECMWF HAS THE
LOW TAKING NEARLY THE SAME TRACK AS THE GFS, JUST ABOUT 12 HOURS
BEHIND. BOTH HAVE HIGH PRESSURE BUILDING IN FOR SUNDAY.
GIVEN THE TIMING DIFFERENCES AND HOW FAR OUT THIS SYSTEM IS, WILL
KEEP CHC POPS IN THE FORECAST FROM FRIDAY THROUGH SATURDAY.
LOOKING AT THE AIR MASS TEMPS, IT DOES LOOK AS THOUGH IT SHOULD BE
COLD ENOUGH TO SUPPORT ALL SNOW WITH THIS SYSTEM.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
MODELS ALL SHOW THE CEILING BREAKING UP OVER THE NEXT 3 HOURS AS
DRY AIR UNDERCUTS THE INVERSION. TEMPO MVFR CONDITIONS WILL
PERSIST FOR THE NEXT FEW HOURS AT BGM AND ITH, THEN QUICKLY RISE
TO VFR.
IT WILL BE A QUIET OVERNIGHT WITH LIGHT WINDS AND CIRRUS OVERHEAD.
PRECIPITATION AHEAD OF AN ADVANCING STORM SYSTEM MAY REACH THE AVP
TERMINAL BETWEEN 17Z AND 20Z ON TUESDAY. AT THIS POINT WE ARE NOT
CONFIDENT ENOUGH OF THE ONSET TIME TO PUT IT IN THE CURRENT TAF
PACKAGE. THE 0Z PACKAGE WILL CONTAIN FORECAST PRECIP START TIMES
FOR ALL TERMINALS.
.OUTLOOK...
TUE MORN...VFR.
TUE AFTN/TUE NGT/WED MORN...MVFR IN RAIN DROPPING TO IFR IN SNOW
SHOWERS TUESDAY NIGHT.
WED AFTN/THU...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...SLI/TAC
AVIATION...DJP
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
337 AM EST WED DEC 28 2011
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION TODAY AND LINGER THROUGH
FRIDAY. A COLD FRONT WILL PUSH THROUGH THE AREA FRIDAY NIGHT.
ANOTHER AREA OF HIGH PRESSURE WILL BUILD IN THIS WEEKEND. A STRONG
COLD FRONT WILL PUSH THROUGH SUNDAY NIGHT OR EARLY MONDAY OF NEXT
WEEK.
&&
.NEAR TERM /TODAY/...
AS OF 3 AM WED...CURRENT H20 VAPOR ANALYSIS INDICATING H7 TROUGH
AXIS SWINGING THROUGH CENTRAL NC ATTM. MODEST CAA CONTINUES TO
KEEP WINDS IN THE 10 TO 15 KT RANGE AT THE SFC EARLY THIS MORNING.
RUC ANALYSIS INDICATES LARGEST PRES RISES CONTINUING THROUGH LATE
MORNING TODAY...WHICH IN CONJUNCTION WITH EFFICIENT UNIDIRECTIONAL
SHEAR IN THE BL WILL BRING DOWN WINDS ALOFT IN THE FORM OF GUSTS
IN THE 20 TO 25 KT RANGE AT THE SFC. GRADIENT WILL REMAIN
STRONGEST ACROSS THE OBX AND WITH GOOD MIXING...WILL LEAVE THE
CURRENT WIND ADVISORY IN EFFECT...THOUGH CRITERIA WILL BE
MARGINAL. GRADIENT RELAXES THIS AFTERNOON AND WINDS WILL DIMINISH
IN RESPONSE.
FOR TEMP FCST...USED MODEL BLEND OF THE BIAS CORRECTED GFS/SREF
GRIDS AND 1000-850 MB THICKNESSES TO YIELD HIGHS GENERALLY IN THE
LOWER 50S ACROSS E NC. IT WILL FEEL QUITE A BIT COOLER DUE TO THE
BRISK WESTERLY WINDS HOWEVER. SKIES WILL BE MOSTLY SUNNY AS DEEP
LAYER DRYING CONTINUES THROUGH THE DAY.
&&
.SHORT TERM /TONIGHT/...
AS OF 3 AM WED...GUSTY WINDS OF TODAY WILL DIMINISH QUITE RAPIDLY
TOWARDS SUNSET THIS EVENING AS PRES GRADIENT WEAKENS AND DRY HIGH
PRES BEGINS BUILDING IN FROM THE WEST. TD VALS WILL PLUMMET
THROUGH THE 20S AND WITH CLEAR SKIES AND CALM WINDS OVERNIGHT...
MIN TEMPS WILL FOLLOW SUIT AND SETTLE INTO THE 20S FOR AREAS AWAY
FROM THE IMMEDIATE COAST. NW WINDS WILL CONTINUE FOR THE OBX WITH
LOWS HERE IN THE 30S.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 300 AM WED...NO SIGNIFICANT CHANGES TO PREVIOUS FCST DURING
PERIOD. MODELS IN DECENT AGREEMENT WITH NEAR ZONAL FLOW PATTERN INTO
EARLY NEXT WEEK...WITH STRONGEST NORTHERN STREAM SHRT WV MOVING
THROUGH SAT. GULFMEX WILL BE CUTOFF SO JUST A DRY FRONTAL PASSAGE
EXPECTED AT SFC WITH THIS SYSTEM. DID ADJUST TEMPS THU-FRI BASED ON
LATEST MOS GDNC BLEND.
MODELS CONTINUE TO INDICATE UPR TROFFING OVER ERN US MON INTO TUE.
00Z ECMWF MORE PROGRESSIVE THAN PREVIOUS RUNS WITH TROF...WITH SFC
LOW DEVELOPMENT FARTHER OFFSHORE MIDWEEK...BUT LIKELY OVERDONE WITH
DEPTH OF TROF PER EXTENDED PROG DISCUSSIONS. MODELS DO CONTINUE TO
INDICATE ENOUGH DYNAMICS WITH UPR SYSTEM TO KEEP 20 POPS FOR SUN
NIGHT AND MONDAY.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 3 AM WED...WEST WINDS BEHIND SFC FRONT WILL REMAIN QUITE
STRONG THROUGH EARLY THIS MORNING AS TIGHT GRAD REMAINS AND STRONG
CAA UNDERWAY. PRES RISES WILL BE GREATEST THROUGH THE MORNING AND
WITH GOOD MIXING TODAY...WILL SEE WINDS GUSTING INTO THE 20 TO 25
KT RANGE FOR ALL TERMINALS. SKIES WILL BE SUNNY AS DRY HIGH PRES
BUILDS IN. WINDS DIMINISH DRASTICALLY TOWARDS SUNSET AS THE
GRADIENT RELAXES AND CAA COMES TO A HALT. DO NOT EXPECT FOG OR BR
AS BNDRY LAYER WILL BE QUITE DRY WITH TD VALS IN THE LOW TO MID
20S OVERNIGHT.
LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 300 AM WED...VFR THROUGH THE PERIOD. ISOLATED SHOWERS
POSSIBLE SUNDAY NIGHT WITH A STONGER UPR LEVEL TROF.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/
AS OF 3 AM WED...CURRENT SFC OBS INDICATING MARGINAL GALE
CONDITIONS OCCURING OFF NC COAST. FRYING PAN BUOY GUSTING BETWEEN
35 AND 40 KT EARLY THIS MORNING...AND EARLIER SHIP OB 35 SE CAPE
LOOKOUT REPORTED SUSTAINED WINDS OF 35 KT. NEAR TERM GUIDANCE
INDICATES GREATEST ISALLOBARIC PRES RISES OCCURRING NEAR 12 Z THIS
MORNING. THIS IS IN LINE WITH HRRR WINDS GUSTS APPROACHING GALE
FORCE THROUGH ABOUT THIS TIME. 700 MB TROUGH AXIS WILL EXIT THE NC
COASTAL WATERS AFTER 12Z...AND WITH DEPARTING THOUGH DEEPENING LOW
ACROSS NEW ENGLAND...WINDS WILL BEGIN TO ABATE. CAA HOWEVER WILL
CONTINUE TO PRODUCE SCA WIND GUSTS THROUGH MUCH OF TODAY...AND
WILL HAVE TO REPLACE GALES WITH SCA AFTER THEIR SCHEDULED
EXPIRATION TIMES. SEAS WILL ALSO REMAIN ABOVE 6 FT FOR THE
REMAINDER OF TODAY...HIGHEST EARLY THIS MORNING.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 300 AM WED...BRIEF PERIOD OF LIGHTER WINDS AND SEAS THU
MORNING...THEN GRADIENT BETWEEN LOW PRESSURE MOVING ACROSS N OF AREA
AND HIGH PRESSURE TO S WILL PRODUCE INCREASING W TO SW WINDS THU
NIGHT INTO FRI NIGHT...WITH MARGINAL SCA CONDITIONS PSBL FOR OUTER
PORTIONS OF WATERS. WINDS BECOMING NRLY LATE SAT FOLLOWING DRY
FRONTAL PASSAGE...WITH SPEEDS DECREASING SAT NIGHT WITH HIGH PRES
BUILDING IN FROM W. WINDS WILL VEER QUICKLY BACK TO SW SUN AS HIGH
PRES MOVES OFFSHORE. BLEND OF WW3...LOCAL SWAN AND PREVIOUS FCST
USED FOR SEAS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...WIND ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR NCZ103-104.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR AMZ130-
135.
GALE WARNING UNTIL 10 AM EST THIS MORNING FOR AMZ150-152-154.
GALE WARNING UNTIL 7 AM EST THIS MORNING FOR AMZ156-158.
&&
$$
SYNOPSIS...TL
NEAR TERM...TL
SHORT TERM...TL
LONG TERM...JBM
AVIATION...TL/JBM
MARINE...TL/JBM
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
241 PM EST MON DEC 26 2011
.SYNOPSIS...
HIGH PRESSURE WILL BUILD IN FROM THE WEST TODAY...THEN MOVE OFFSHORE
TONIGHT. A COMPLEX LOW PRESSURE SYSTEM WILL APPROACH THE AREA FROM
THE SOUTHWEST TUESDAY. THE LOW WILL PASS NORTH OF THE AREA TUESDAY
EVENING WHILE SWINGING A COLD FRONT THROUGH THE REGION TUESDAY
NIGHT. HIGH PRESSURE BUILDS OVER THE AREA WEDNESDAY THROUGH THE END
OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 130 PM MON...RIDGING CONTINUES TO MOVE EAST ACROSS THE
REGION...ACTING TO VEER WINDS MORE NORTHEASTERLY AS THE AFTERNOON
PROGRESSES. SITES ACROSS THE COASTAL PLAIN ARE CURRENTLY GUSTING
TO 15-20 KNOTS...WHICH IS EXPECTED TO CONTINUE THROUGHOUT THE REST
OF THE AFTERNOON. VIS/WV SATELLITE AND FORECAST SOUNDINGS
ILLUSTRATE VERY DRY AIRMASS ALOFT SO EXPECT SUNNY SKIES TO PREVAIL
WITH A FEW HIGH CIRRUS POSSIBLE ACROSS SOUTHERN PORTIONS LATE
TODAY. LOW LEVEL THICKNESSES REMAIN LOWER TODAY...WITH 1000-850
MB THICKNESSES EXPECTED IN THE 1325-1330 METER RANGE. NO
SIGNIFICANT CHANGES NEEDED FOR THE NEAR TERM FORECAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
AS OF 300 AM MONDAY...WINDS WILL DIMINISH TONIGHT AS HIGH PRES MOVES
ACROSS. DON`T EXPECT MUCH IN THE WAY OF CLOUDS UNTIL LATE
SO WITH DRY AMS IN PLACE EXPECT GOOD RADIATIONAL COOLING WITH MIN
TEMPS FROM THE LOWER 30S INLAND TO AROUND 40 ON THE COAST.
&&
.LONG TERM /TUESDAY THROUGH MONDAY/...
AS OF 240 PM MONDAY...WIDESPREAD HEAVY SHOWERS/POSSIBLE STRONG
THUNDERSTORMS WILL BE MOVING OFF OF THE COAST A LITTLE AFTER 00Z
TUESDAY EVENING. STRONG GRADIENT WINDS WILL BE ASSOCIATED WITH THE
FRONT AND WIND ADVISORY CONDITIONS WILL BE POSSIBLE ALONG THE
IMMEDIATE COAST THROUGH EARLY WEDNESDAY. ALTHOUGH THE BULK OF THE
RAINFALL WILL BE OVER AROUND 00Z...THE STRONG MID LEVEL SHORTWAVE
WILL NOT CROSS THE AREA UNTIL AFTER MIDNIGHT SO THE THREAT FOR
SHOWERS WILL PERSIST THROUGH ABOUT 06Z WEDNESDAY. EASTERN NC WILL
RECEIVE SOME MUCH NEEDED RAINFALL WITH AMOUNTS OF 0.50"-0.75"
EXPECTED MOST AREAS WITH LOCAL AMOUNTS IN EXCESS OF 1 INCH POSSIBLE.
LOW TEMPERATURES WILL RANGE FROM THE UPPER 30S INLAND TO THE MIDDLE
40S COAST.
THE UPPER LEVEL FLOW WILL BECOME MORE ZONAL AND VERY FAST THROUGH
THE MID TO LATE WEEK TIME FRAME...CUTTING OFF ANY GULF OF MEXICO
INFLOW...WITH SEVERAL DRY NORTHERN STREAM SHORT WAVES PROMPTING A
SERIES DRY COLD FRONTAL PASSAGES ACROSS THE AREA THURSDAY
NIGHT...SATURDAY AND SUNDAY NIGHT. NEAR SEASONABLE TEMPERATURES ARE
EXPECTED ACROSS THE REGION THROUGH THE PERIOD.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH TUESDAY/...
AS OF 130 PM MON...HIGH PRESSURE WILL REMAIN IN CONTROL OF THE
SENSIBLE WEATHER THROUGH THIS EVENING...AHEAD OF AN APPROACHING
COMPLEX LOW PRESSURE SYSTEM THAT WILL IMPACT THE REGION LATE
TONIGHT THROUGH TUESDAY. NORTHERLY WINDS HAVE BECOME NORTHEASTERLY
THIS AFTERNOON GUSTING UPWARDS OF 20 KNOTS DUE IN PART TO
EXCELLENT MIXING AND STRONG CAA ACROSS THE REGION. VERY DRY ATMOS
IN PLACE SO DO NOT EXPECT STRATOCUMULUS DEVELOPMENT THIS
AFTERNOON. MID/HIGH CLOUDS DO NOT BEGIN IMPACTING WESTERN TAF
SITES/ISO/OAJ/PGV UNTIL NEAR SUNRISE TUES MORNING. WINDS WILL
CONTINUE VEERING OVERNIGHT...TO A MORE SOUTHEASTERLY RETURN FLOW
BY SUNRISE. OVERALL DRY ATMOS AND WINDS AROUND 4-6 KT OVERNIGHT
SHOULD INHIBIT ANY FOG FORMATION...THUS EXPECT VFR CONDITIONS
OVERNIGHT AS WELL.
PRECIP WILL BEGIN TO OVERSPREAD THE REGION FROM WEST TO EAST TUES.
A WARM FRONT WILL LIFT THROUGH THE REGION EARLY TUES
MORNING...SHELTERING IN DEWPOINTS IN THE UPPER 50S TO LOWER 60S.
WINDS WILL VEER FURTHER...EVENTUALLY BECOMING SOUTHWEST 15-20
KNOTS WITH SOME 25-30 KNOT GUSTS. LOW LEVEL JET OF 25-30 KNOTS
JUST OFF THE SURFACE TO 60-70 KNOTS AT 850MB WILL LEAD TO LOW
LEVEL WIND SHEAR CONCERNS. THE FRONT WILL EXIT OFF THE COAST LATE
TUES EVENING WITH CLEARING SKIES AND IMPROVING CONDITIONS FROM
WEST TO EAST. EXPECT MVFR IN LOWERED CEILINGS AND VISIBILITIES
FROM ABOUT 15Z TUES TO 06Z WED...WITH ISOLATED IFR/LIFR POSSIBLE
IN HEAVIER SHOWERS.
LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 230 PM MONDAY...SUB-VFR CONDITIONS ARE LIKELY TUESDAY NIGHT.
ALTHOUGH THE STRONG COLD FRONT AND THE BULK OF THE MOISTURE WILL
MOVE OFF OF THE COAST IN THE EARLY EVENING...THE STRONG MID LEVEL
SHORTWAVE WILL NOT CROSS THE AREA UNTIL AFTER MIDNIGHT. LOW CLOUDS
AND LIGHT SHOWERS WILL BE POSSIBLE UNTIL AFTER THE SHORTWAVE PASSES.
PREVAILING VFR CONDITIONS ARE THEN EXPECTED WEDNESDAY THROUGH
SATURDAY AS A PREDOMINATELY DRY WESTERLY FLOW PREVAILS ACROSS
EASTERN NC.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 1010 AM MON...LATEST SURFACE AND BUOY OBSERVATIONS INDICATE
SMALL CRAFT CONDITIONS ACROSS THE COASTAL WATERS. NORTHWEST TO
NORTH-NORTHWEST WINDS 20-25 KNOTS WITH GUSTS NEAR 30 KNOTS HAVE
BEEN OBSERVED ACROSS THE NORTHERN COASTAL WATERS...WITH 20 KNOTS
GUSTING TO 25 KNOTS ELSEWHERE. SEAS HAVE BUILT TO 5 TO 7 FT OFF
DUCK BUT EXPECT SEAS 6-8 FT FARTHER OFFSHORE. GIVEN CURRENT
SCENARIO AND LATEST 12Z NAM/14Z RUC GUIDANCE...HAVE EXTENDED THE
SCAS FOR THE SOUTHERN COASTAL WATERS UNTIL NOON...THE PAMLICO AND
ALBEMARLE SOUNDS UNTIL 2PM...AND THE CENTRAL WATERS REMAIN THROUGH
LATE THIS EVENING.
HIGH PRESSURE WILL CONTINUE TO MIGRATE EAST ACROSS THE WATERS
TODAY. THE RIDGE WILL CREST ACROSS THE WATERS OVERNIGHT...ALLOWING
WINDS TO VEER FURTHER...BECOMING EAST LATE AND DIMINISHING 10-15
KNOTS...THEN SOUTHEAST BY SUNRISE TUES. SEAS WILL DIMINISH BELOW
SCA LEVELS LATER THIS EVENING AS WELL.
LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 240 PM MONDAY...THE STRONG COLD FRONT WILL CROSS THE NC WATERS
TUESDAY EVENING WITH STRONG SMALL CRAFT ADVISORY CONDITIONS/POSSIBLE
MARGINAL GALES EXPECTED...ESPECIALLY OVER THE CENTRAL WATERS. SEAS
WILL PEAK AROUND 13 FT IN THE EVENING. WINDS WILL DIMINISH AND SEAS
WILL SUBSIDE VERY LATE WEDNESDAY (AFTER 18Z) AS LOW LEVEL COLD
ADVECTION WANES AND HIGH PRESSURE BUILDS OVER THE WATERS. LIGHTER
NORTHWEST TO WEST WINDS 15 KT OR LESS ARE EXPECTED WEDNESDAY NIGHT
AND THURSDAY AS HIGH PRESSURE CRESTS OVER THE WATERS. WESTERLY FLOW
INCREASES TO 20 TO 25 KT THURSDAY NIGHT AND FRIDAY PRODUCING
MARGINAL SMALL CRAFT ADVISORY CONDITIONS AS A DRY COLD FRONT CROSSES
THE WATERS. WILL FORECAST IMPROVING CONDITIONS ON SATURDAY.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR AMZ150-
152-154.
&&
$$
SYNOPSIS...DAG
NEAR TERM...DAG
SHORT TERM...JAC
LONG TERM...JME
AVIATION...JME/DAG
MARINE...JME/DAG
AREA FORECAST DISCUSSION...UPDATED
NWS NEWPORT/MOREHEAD CITY NC
137 PM EST MON DEC 26 2011
.SYNOPSIS...
HIGH PRESSURE WILL BUILD IN FROM THE WEST TODAY...THEN MOVE OFFSHORE
TONIGHT. A COMPLEX LOW PRESSURE SYSTEM WILL APPROACH THE AREA FROM
THE SOUTHWEST TUESDAY. THE LOW WILL PASS NORTH OF THE AREA TUESDAY
EVENING WHILE SWINGING A COLD FRONT THROUGH THE REGION TUESDAY
NIGHT. HIGH PRESSURE BUILDS OVER THE AREA WEDNESDAY THROUGH THE END
OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 130 PM MON...RIDGING CONTINUES TO MOVE EAST ACROSS THE
REGION...ACTING TO VEER WINDS MORE NORTHEASTERLY AS THE AFTERNOON
PROGRESSES. SITES ACROSS THE COASTAL PLAIN ARE CURRENTLY GUSTING
TO 15-20 KNOTS...WHICH IS EXPECTED TO CONTINUE THROUGHOUT THE REST
OF THE AFTERNOON. VIS/WV SATELLITE AND FORECAST SOUNDINGS
ILLUSTRATE VERY DRY AIRMASS ALOFT SO EXPECT SUNNY SKIES TO PREVAIL
...WITH A FEW HIGH CIRRUS POSSIBLE ACROSS SOUTHERN PORTIONS LATE
TODAY. LOW LEVEL THICKNESSES REMAIN LOWER TODAY...WITH 1000-850
MB THICKNESSES EXPECTED IN THE 1325-1330 METER RANGE. NO
SIGNIFICANT CHANGES NEEDED FOR THE NEAR TERM FORECAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
AS OF 300 AM MONDAY...WINDS WILL DIMINISH TONIGHT AS HIGH PRES MOVES
ACROSS. DON`T EXPECT MUCH IN THE WAY OF CLOUDS UNTIL LATE
SO WITH DRY AMS IN PLACE EXPECT GOOD RADIATIONAL COOLING WITH MIN
TEMPS FROM THE LOWER 30S INLAND TO AROUND 40 ON THE COAST.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
AS OF 315 AM MONDAY...MODELS CONTINUE TO INDICATE MOST SIGNIFICANT
WEATHER DURING PERIOD WILL OCCUR TUE AND TUE NIGHT WITH COMPLEX UPR
AND SFC FEATURES AFFECTING AREA. SLOW MOVING UPR LOW NEAR NRN TEXAS
WILL BE PICKED UP BY DIVING NRN STREAM SHRT WV LATE TODAY AND
TONIGHT...WITH SRN STREAM SYSTEM BEING DAMPENED AS IT MERGES WITH
NRN STREAM OVER ERN U.S. LATE TUE. RESULTING SFC LOW TRACK W AND N
OF AREA AND UPR LVL DYNAMICS WILL PRODUCE MARGINAL SVR THREAT...LOW
CAPE BUT HIGH SHEAR...OVER ERN NC TUE AFTN AND EVENING. PER SPC DAY
2 OUTLOOK...MORE SIGNIFICANT THREAT WILL BE JUST S-SW OF AREA WITH
SLIGHTLY BETTER INSTABILITY. WILL CONTINUE MENTION IN HWO.
ADDITIONALLY...INCREASING WINDS MAY REACH ADVISORY CRITERIA ALONG
COASTAL SECTIONS...MAINLY OUTER BANKS...LATE TUE AFTN INTO EARLY
EVENING...AND WILL ADD MENTION OF THIS TO HWO AS WELL.
WITH SLIGHTLY BETTER MODEL AGREEMENT...RAISED POPS TO CATEGORICAL
LATE TUE AFTN AND ENDED POPS EARLIER INLAND TUE EVENING...WITH MINOR
ADJUSTMENTS TO TEMPS AND SKY COVER.
NO SIGNIFICANT CHANGES TO FCST FOR REST OF PERIOD. UPR FLOW WILL
BECOME MORE ZONAL...CUTTING OFF GULFMEX FEED...WITH MAINLY DRY NRN
STREAM SHRT WVS AFFECTING AREA THU AND AGAIN SAT. TEMPS WILL BE NEAR
SEASONAL WED-SUN.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH TUESDAY/...
AS OF 130 PM MON...HIGH PRESSURE WILL REMAIN IN CONTROL OF THE
SENSIBLE WEATHER THROUGH THIS EVENING...AHEAD OF AN APPROACHING
COMPLEX LOW PRESSURE SYSTEM THAT WILL IMPACT THE REGION LATE
TONIGHT THROUGH TUESDAY. NORTHERLY WINDS HAVE BECOME NORTHEASTERLY
THIS AFTERNOON GUSTING UPWARDS OF 20 KNOTS DUE IN PART TO
EXCELLENT MIXING AND STRONG CAA ACROSS THE REGION. VERY DRY ATMOS
IN PLACE SO DO NOT EXPECT STRATOCUMULUS DEVELOPMENT THIS
AFTERNOON. MID/HIGH CLOUDS DO NOT BEGIN IMPACTING WESTERN TAF
SITES/ISO/OAJ/PGV UNTIL NEAR SUNRISE TUES MORNING. WINDS WILL
CONTINUE VEERING OVERNIGHT...TO A MORE SOUTHEASTERLY RETURN FLOW
BY SUNRISE. OVERALL DRY ATMOS AND WINDS AROUND 4-6 KT OVERNIGHT
SHOULD INHIBIT ANY FOG FORMATION...THUS EXPECT VFR CONDITIONS
OVERNIGHT AS WELL.
PRECIP WILL BEGIN TO OVERSPREAD THE REGION FROM WEST TO EAST TUES.
A WARM FRONT WILL LIFT THROUGH THE REGION EARLY TUES
MORNING...SHELTERING IN DEWPOINTS IN THE UPPER 50S TO LOWER 60S.
WINDS WILL VEER FURTHER...EVENTUALLY BECOMING SOUTHWEST 15-20
KNOTS WITH SOME 25-30 KNOT GUSTS. LOW LEVEL JET OF 25-30 KNOTS
JUST OFF THE SURFACE TO 60-70 KNOTS AT 850MB WILL LEAD TO LOW
LEVEL WIND SHEAR CONCERNS. THE FRONT WILL EXIT OFF THE COAST LATE
TUES EVENING WITH CLEARING SKIES AND IMPROVING CONDITIONS FROM
WEST TO EAST. EXPECT MVFR IN LOWERED CEILINGS AND VISIBILITIES
FROM ABOUT 15Z TUES TO 06Z WED...WITH ISOLATED IFR/LIFR POSSIBLE
IN HEAVIER SHOWERS.
LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 315 AM MONDAY...SUB-VFR CONDITIONS ARE LIKELY TUESDAY INTO
TUESDAY EVENING IN WIDESPREAD SHOWERS/POSSIBLE STRONG THUNDERSTORMS
THAT ARE FORECAST TO OCCUR ALONG/AHEAD OF A STRONG COLD FRONT WHICH
WILL CROSS THE AREA TUESDAY NIGHT. PREVAILING VFR CONDITIONS ARE
THEN EXPECTED WEDNESDAY THROUGH FRIDAY AS A RELATIVELY DRY AIRMASS
EXTENDS OVER THE AREA.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 1010 AM MON...LATEST SURFACE AND BUOY OBSERVATIONS INDICATE
SMALL CRAFT CONDITIONS ACROSS THE COASTAL WATERS. NORTHWEST TO
NORTH-NORTHWEST WINDS 20-25 KNOTS WITH GUSTS NEAR 30 KNOTS HAVE
BEEN OBSERVED ACROSS THE NORTHERN COASTAL WATERS...WITH 20 KNOTS
GUSTING TO 25 KNOTS ELSEWHERE. SEAS HAVE BUILT TO 5 TO 7 FT OFF
DUCK BUT EXPECT SEAS 6-8 FT FARTHER OFFSHORE. GIVEN CURRENT
SCENARIO AND LATEST 12Z NAM/14Z RUC GUIDANCE...HAVE EXTENDED THE
SCAS FOR THE SOUTHERN COASTAL WATERS UNTIL NOON...THE PAMLICO AND
ALBEMARLE SOUNDS UNTIL 2PM...AND THE CENTRAL WATERS REMAIN THROUGH
LATE THIS EVENING.
HIGH PRESSURE WILL CONTINUE TO MIGRATE EAST ACROSS THE WATERS
TODAY. THE RIDGE WILL CREST ACROSS THE WATERS OVERNIGHT...ALLOWING
WINDS TO VEER FURTHER...BECOMING EAST LATE AND DIMINISHING 10-15
KNOTS...THEN SOUTHEAST BY SUNRISE TUES. SEAS WILL DIMINISH BELOW
SCA LEVELS LATER THIS EVENING AS WELL.
LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 315 AM MONDAY...STRONG SCA TO MARGINAL GALE CONDITIONS ARE
LIKELY TUE AND TUE NIGHT AS DEVELOPING LOW PRES TRACKS W AND N OF
THE AREA...AND PUSHES A STRONG COLD FRONT THROUGH THE AREA FROM THE
WEST. MARINERS CAN EXPECT SOUTHERLY FLOW TO 30 KT OR HIGHER TUESDAY
SHIFTING TO WESTERLY THEN NORTHWESTERLY AT 30 KT OR HIGHER TUESDAY
NIGHT. IN THIS FLOW SEAS WILL LIKELY REACH OR EXCEED 10 FT FOR A
PERIOD TUESDAY INTO TUESDAY NIGHT. HIGHEST WINDS/SEAS ARE EXPECTED
OVER THE CENTRAL WATERS. WINDS WILL DIMINISH AND SEAS WILL SUBSIDE
LATE WEDNESDAY AS COLD ADVECTION WANES AND HIGH PRESSURE BUILDS OVER
THE WATERS. THE BROAD HIGH WILL CONTINUE OVER THE WATERS THURSDAY
THEN SHIFT OFFSHORE FRIDAY WITH WINDS 10-15 KT EXPECTED BOTH DAYS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR AMZ150-
152-154.
SMALL CRAFT ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR AMZ130-
135.
&&
$$
SYNOPSIS...DAG
NEAR TERM...DAG
SHORT TERM...JAC
LONG TERM...JBM
AVIATION...JBM/JME/DAG
MARINE...JBM/JME/DAG
AREA FORECAST DISCUSSION...UPDATED
NWS NEWPORT/MOREHEAD CITY NC
1010 AM EST MON DEC 26 2011
.SYNOPSIS...
HIGH PRESSURE WILL BUILD IN FROM THE WEST TODAY...THEN MOVE OFFSHORE
TONIGHT. A COMPLEX LOW PRESSURE SYSTEM WILL APPROACH THE AREA FROM
THE SOUTHWEST TUESDAY. THE LOW WILL PASS NORTH OF THE AREA TUESDAY
EVENING WHILE SWINGING A COLD FRONT THROUGH THE REGION TUESDAY
NIGHT. HIGH PRESSURE BUILDS OVER THE AREA WEDNESDAY THROUGH THE END
OF THE WEEK.
&&
.NEAR TERM /TODAY/...
AS OF 10 AM MON...RIDGING CONTINUES TO MOVE EAST ACROSS THE
REGION...ACTING TO VEER WINDS MORE NORTHERLY AS THE DAY
PROGRESSES. SITES ACROSS THE COASTAL PLAIN ARE CURRENTLY GUSTING
TO 15 KNOTS...WHICH IS EXPECTED TO CONTINUE THROUGHOUT THE DAY AS
STRONG COLD AIR ADVECTION IMPACTS THE REGION. KMHX/KGSO 12Z AND
FORECAST SOUNDINGS ILLUSTRATE VERY DRY AIRMASS ALOFT SO EXPECT
SUNNY SKIES TO PREVAIL TODAY...WITH A FEW HIGH CIRRUS POSSIBLE
ACROSS SOUTHERN PORTIONS. LOW LEVEL THICKNESSES REMAIN LOWER
TODAY...WITH 1000-850 MB THICKNESSES EXPECTED IN THE 1325-1330
METER RANGE. GIVEN WARMING TREND SLIGHTLY QUICKER THAN FORECAST
THIS MORNING...BUMPED TEMPS UP A FEW DEGREES MAINLY FOR INLAND
LOCATIONS.
&&
.SHORT TERM /TONIGHT/...
AS OF 300 AM MONDAY...WINDS WILL DIMINISH TONIGHT AS HIGH PRES MOVES
ACROSS. DON`T EXPECT MUCH IN THE WAY OF CLOUDS UNTIL LATE
SO WITH DRY AMS IN PLACE EXPECT GOOD RADIATIONAL COOLING WITH MIN
TEMPS FROM THE LOWER 30S INLAND TO AROUND 40 ON THE COAST.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
AS OF 315 AM MONDAY...MODELS CONTINUE TO INDICATE MOST SIGNIFICANT
WEATHER DURING PERIOD WILL OCCUR TUE AND TUE NIGHT WITH COMPLEX UPR
AND SFC FEATURES AFFECTING AREA. SLOW MOVING UPR LOW NEAR NRN TEXAS
WILL BE PICKED UP BY DIVING NRN STREAM SHRT WV LATE TODAY AND
TONIGHT...WITH SRN STREAM SYSTEM BEING DAMPENED AS IT MERGES WITH
NRN STREAM OVER ERN U.S. LATE TUE. RESULTING SFC LOW TRACK W AND N
OF AREA AND UPR LVL DYNAMICS WILL PRODUCE MARGINAL SVR THREAT...LOW
CAPE BUT HIGH SHEAR...OVER ERN NC TUE AFTN AND EVENING. PER SPC DAY
2 OUTLOOK...MORE SIGNIFICANT THREAT WILL BE JUST S-SW OF AREA WITH
SLIGHTLY BETTER INSTABILITY. WILL CONTINUE MENTION IN HWO.
ADDITIONALLY...INCREASING WINDS MAY REACH ADVISORY CRITERIA ALONG
COASTAL SECTIONS...MAINLY OUTER BANKS...LATE TUE AFTN INTO EARLY
EVENING...AND WILL ADD MENTION OF THIS TO HWO AS WELL.
WITH SLIGHTLY BETTER MODEL AGREEMENT...RAISED POPS TO CATEGORICAL
LATE TUE AFTN AND ENDED POPS EARLIER INLAND TUE EVENING...WITH MINOR
ADJUSTMENTS TO TEMPS AND SKY COVER.
NO SIGNIFICANT CHANGES TO FCST FOR REST OF PERIOD. UPR FLOW WILL
BECOME MORE ZONAL...CUTTING OFF GULFMEX FEED...WITH MAINLY DRY NRN
STREAM SHRT WVS AFFECTING AREA THU AND AGAIN SAT. TEMPS WILL BE NEAR
SEASONAL WED-SUN.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
SHORT TERM /THROUGH TONIGHT/...
AS OF 10 AM MON...HIGH PRESSURE WILL REMAIN IN CONTROL OF THE
SENSIBLE WEATHER THROUGH TODAY. NORTH-NORTHWEST WINDS WILL
CONTINUE AROUND 10 KNOTS WITH GUSTS NEAR 20 KNOTS...BECOMING NORTH
LATER THIS AFTERNOON. VERY DRY ATMOS IN PLACE SO DO NOT EXPECT
STRATOCUMULUS DEVELOPMENT THIS AFTERNOON. MID/HIGH CLOUDS DO NOT
BEGIN IMPACTING WESTERN TAF SITES/ISO/OAJ/PGV UNTIL NEAR SUNRISE
TUES MORNING. WINDS WILL CONTINUE VEERING OVERNIGHT...TO A MORE
SOUTHERLY RETURN FLOW BY SUNRISE. OVERALL DRY ATMOS AND WINDS
AROUND 4-6 KT OVERNIGHT SHOULD INHIBIT ANY FOG FORMATION. THUS
EXPECT VFR CONDITIONS OVERNIGHT AS WELL.
LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 315 AM MONDAY...SUB-VFR CONDITIONS ARE LIKELY TUESDAY INTO
TUESDAY EVENING IN WIDESPREAD SHOWERS/POSSIBLE STRONG THUNDERSTORMS
THAT ARE FORECAST TO OCCUR ALONG/AHEAD OF A STRONG COLD FRONT WHICH
WILL CROSS THE AREA TUESDAY NIGHT. PREVAILING VFR CONDITIONS ARE
THEN EXPECTED WEDNESDAY THROUGH FRIDAY AS A RELATIVELY DRY AIRMASS
EXTENDS OVER THE AREA.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 1010 AM MON...LATEST SURFACE AND BUOY OBSERVATIONS INDICATE
SMALL CRAFT CONDITIONS ACROSS THE COASTAL WATERS. NORTHWEST TO
NORTH-NORTHWEST WINDS 20-25 KNOTS WITH GUSTS NEAR 30 KNOTS HAVE
BEEN OBSERVED ACROSS THE NORTHERN COASTAL WATERS...WITH 20 KNOTS
GUSTING TO 25 KNOTS ELSEWHERE. SEAS HAVE BUILT TO 5 TO 7 FT OFF
DUCK BUT EXPECT SEAS 6-8 FT FARTHER OFFSHORE. GIVEN CURRENT
SCENARIO AND LATEST 12Z NAM/14Z RUC GUIDANCE...HAVE EXTENDED THE
SCAS FOR THE SOUTHERN COASTAL WATERS UNTIL NOON...THE PAMLICO AND
ALBEMARLE SOUNDS UNTIL 2PM...AND THE CENTRAL WATERS REMAIN THROUGH
LATE THIS EVENING.
HIGH PRESSURE WILL CONTINUE TO MIGRATE EAST ACROSS THE WATERS
TODAY. THE RIDGE WILL CREST ACROSS THE WATERS OVERNIGHT...ALLOWING
WINDS TO VEER FURTHER...BECOMING EAST LATE AND DIMINISHING 10-15
KNOTS...THEN SOUTHEAST BY SUNRISE TUES. SEAS WILL DIMINISH BELOW
SCA LEVELS LATER THIS EVENING AS WELL.
LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 315 AM MONDAY...STRONG SCA TO MARGINAL GALE CONDITIONS ARE
LIKELY TUE AND TUE NIGHT AS DEVELOPING LOW PRES TRACKS W AND N OF
THE AREA...AND PUSHES A STRONG COLD FRONT THROUGH THE AREA FROM THE
WEST. MARINERS CAN EXPECT SOUTHERLY FLOW TO 30 KT OR HIGHER TUESDAY
SHIFTING TO WESTERLY THEN NORTHWESTERLY AT 30 KT OR HIGHER TUESDAY
NIGHT. IN THIS FLOW SEAS WILL LIKELY REACH OR EXCEED 10 FT FOR A
PERIOD TUESDAY INTO TUESDAY NIGHT. HIGHEST WINDS/SEAS ARE EXPECTED
OVER THE CENTRAL WATERS. WINDS WILL DIMINISH AND SEAS WILL SUBSIDE
LATE WEDNESDAY AS COLD ADVECTION WANES AND HIGH PRESSURE BUILDS OVER
THE WATERS. THE BROAD HIGH WILL CONTINUE OVER THE WATERS THURSDAY
THEN SHIFT OFFSHORE FRIDAY WITH WINDS 10-15 KT EXPECTED BOTH DAYS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR AMZ130-
135.
SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR AMZ150-
152-154.
SMALL CRAFT ADVISORY UNTIL NOON EST TODAY FOR AMZ156-158.
&&
$$
SYNOPSIS...DAG
NEAR TERM...DAG
SHORT TERM...JAC
LONG TERM...JBM
AVIATION...JBM/JME/DAG
MARINE...JBM/JME/DAG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
631 AM EST MON DEC 26 2011
.SYNOPSIS...
A DEEPENING LOW PRESSURE SYSTEM IS EXPECTED TO TRACK NORTHEAST FROM
LOUISIANA TODAY AND REACH TENNESSEE AND KENTUCKY EARLY TUESDAY. HIGH
PRESSURE WILL BE BACK IN CONTROL FROM WEDNESDAY UNTIL THE WEEKEND
WHEN A COLD FRONT WILL APPROACH THE AREA FROM THE WEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 610 AM...THE ONLY SITE STILL REPORTING DENSE FOG IS
GREENWOOD...AND CONDITIONS SHOULD IMPROVE THERE SHORTLY.
THEREFORE...THE DENSE FOG ADVISORY WILL NOT BE EXTENDED. TWEAKED
TEMPS AND DEWPOINTS AS DOWNSLOPE MIXING AND DRYING IS CAUSING A
VARIETY OF TEMPS AND DEWPOINTS ACROSS THE AREA.
PREVIOUS DISCUSSION...
DENSE FOG AND LOW CLOUDS CONTINUES ACROSS THE CENTRAL AND EASTERN
PARTS OF THE UPSTATE AND THE EXTREME SRN PIEDMONT OF NORTH CAROLINA.
DRY AIR WILL CONTINUE TO WORK SLOWLY TO THE SOUTH...GRADUALLY MIXING
OUT THE FOG AND LOW CLOUDS. THE RUC AND NAM CONDENSATION PRESSURE
DEFICITS IMPLY LOW CLOUDS AND FOG ARE LIKELY TO PERSIST THE LONGEST
ACROSS GREENVILLE...SPARTANBURG AND LAURENS COUNTIES IN A WEAK LLVL
CONVERGENCE AXIS. WE HAVE A DENSE FOG ADVISORY OVER PARTS OF THE
AREA THROUGH 6 AM. IT WILL LIKELY NEED TO BE CANCELLED EARLY OVER
THE WESTERN UPSTATE AND NE GA...BUT IT STILL LOOKS GOOD FARTHER TO
THE EAST.
A STRONG UPPER LOW OVER WEST TEXAS THIS MORNING WILL EJECT QUICKLY
ACROSS THE LOWER MISSISSIPPI VALLEY TONIGHT AND LIFT ACROSS THE SRN
APPALACHIANS ON TUE AS AN OPEN WAVE. SFC CYCLOGENESIS WILL OCCUR
THIS AFTERNOON OVER THE NRN GULF...WITH THE LOW MOVING ACROSS THE
SRN APPS ON TUE. THE LATEST NAM AND GFS MODEL DATA IS A LITTLE
COLDER ACROSS THE NC MTNS TONIGHT. THE NAM HAS A LARGE AREA OF
1305-1310 METER 1000-850 MB THICKNESSES ACROSS THE SW AND CENTRAL
MTNS AT 0900 UTC...WHICH RETREAT UP ACROSS THE NRN MTNS BY 12 UTC.
NAM MODEL SOUNDINGS AT FRANKLIN AND CASHIERS IMPLY A PERIOD OF SLEET
AND FREEZING RAIN STARTING AFTER MIDNIGHT...WITH PCPN CHANGING TO
ALL RAIN TOWARD MORNING. THE GFS IS A LITTLE WARMER AND LOOKS TO BE
MAINLY LIQUID...WITH JUST A LITTLE SLEET AND A FEW PATCHES OF
FREEZING RAIN AT ONSET. IT STILL APPEARS THAT THE BULK OF THE
COOLING WITH THIS EVENT WILL BE DRIVEN BY OROGRAPHIC ASCENT AS A 60+
KT LLVL WARM SECTOR JET CROSSES THE MTNS. THIS SHOULD CONFINE
WINTRY PCPN TO SOUTH AND EAST REACHES OF THE MTNS...WITH DOWNSLOPE
HELPING TO WARM THE BNDRY LAYER CLOSER TO THE TN LINE. ALSO...NONE
OF THE MODELS IMPLY THAT WINTRY WX WILL HOLD ON ONCE THE HEAVIER
RAIN STARTS OWING TO A STRONG WARM NOSE UP AROUND H8. STILL...A
PERIOD OF LIGHT FREEZING RAIN AND SOME SLEET LOOKS LIKELY ACROSS
THE SW MTNS...AND ALSO ACROSS THE EASTERN ESCARPMENT OF THE BLUE
RIDGE UP IN THE NRN MTNS. AT THE MOST...THIS SHOULD BE A LOW END
ADVISORY LEVEL EVENT WITH ANY GLAZE CONFINED MAINLY TO ELEVATED
SFCS...AND IT WON/T AFFECT THE MTNS UNTIL WELL AFTER DARK TONIGHT.
THEREFORE...I/M GOING TO HOLD OFF ON ANY ADVISORIES WITH THIS
PACKAGE.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 315 AM MONDAY...THE MODELS ARE IN VERY GOOD AGREEMENT ON THE
POSITION OF THE UPPER SHORTWAVE AND SFC LOW PRESSURE AT 12Z TUESDAY.
AN IN SITU WEDGE WILL STILL BE IN PLACE ACRS THE CWFA...WITH SELY
850 MB WINDS OF 50-65 KTS ALOFT. VERY STRONG LLVL WAA AND MECHANICAL
LIFT WITH DEEP MOISTURE WILL BE AIDED BY DECENT QG FORCING AND UPPER
DIVERGENCE. SO A NEAR 100% POP TUESDAY MORNING SEEMS APPROPRIATE.
THERE ARE SOME DIFFERENCES AMONGST THE THERMAL PROFILES/SFC TEMPS
INVOF THE NC MTNS...HOWEVER...AS DYNAMICAL COOLING MAY LOCK IN
SUB-FREEZING TEMPS INVOF THE EAST-FACING SLOPES OF THE NRN MTNS/BLUE
RIDGE ESCARPMENT PAST DAYBREAK TUESDAY MORNING...WITH SOME
ADDITIONAL ICING POSSIBLE. ALL GUIDANCE HAS TEMPS WARMING ABOVE
FREEZING BY 15Z TUE...SO IT STILL LOOKS LIKE ANY TRAVEL PROBLEMS DUE
TO ICE SHUD BE OVER BY MIDDAY.
MIDDAY TUESDAY...THE LOW PRESSURE SYSTEM WILL QUICKLY LIFT
NORTHEASTWARD...WITH A PRIMARY LOW TRACKING ACRS THE TN/OH
VLYS...AND A TRIPLE POINT LOW TRACKING FROM CENTRAL GA TO CENTRAL NC
BY LATE AFTN. THE NAM/GFS/ECWMF ARE IN GOOD AGREEMENT ON THE GSP/CAE
CWFA BORDER AS AN APPROXIMATE TRACK OF THE TRIPLE POINT. SO INSTBY
LOOKS TO STAY SOUTH OF THE FA. THAT IS GOOD...BECAUSE HELICITY
VALUES WILL BE THRU THE ROOF...AND VERY LITTLE INSTBY WOULD BE
SUFFICIENT FOR A SMALL TORNADO/WIND THREAT. THE COLD/OCCLUDED FRONT
WILL CROSS FROM SW TO NE DURING THE AFTN HOURS...QUICKLY TAPERING
OFF POPS (EXCEPT FOR UPSLOPE ALONG TN/NC BORDER). STORM TOTAL QPF
LOOKS TO BE A SOLID 1-1.5" CWFA-WIDE...WITH 2-3" ALONG THE BLUE
RIDGE ESCARPMENT FROM HENDERSON COUNTY WEST. THERE COULD BE A FEW
HYDRO CONCERNS IN THOSE AREAS...BUT NOT WIDESPREAD ENUF TO WARRANT
ANY FLOOD WATCHES ATTM. WITH CLOUDS AND PRECIP...TEMPS WILL BE HELD
DOWN TO MAINLY MID-UPR 40S...EXCEPT ALONG SOUTHEAST EDGE NEAR THE
TMB/WEDGE BNDRY WHERE THEY WILL BE IN THE MID 50S OR HIGHER.
TUESDAY NIGHT...THERE WILL BE STRONG LLVL CAA ACRS THE FA IN THE
WAKE OF THE DEPARTING LOW...WITH GOOD NW FLOW UPSLOPE FORCING ALONG
THE TN/NC BORDER. BOTH THE NAM AND GFS IMPLY AT LEAST SCATTERED
SHOWER ACTIVITY...AND SNOW LEVELS SHUD FALL QUICKLY DURING THE
EVENING HOURS. SOME LOCATIONS MAY GET A QUICK INCH OR TWO
(ESPECIALLY ABOVE 3500 FT). THE SHOWER ACTIVITY LOOKS TO QUICKLY
TAPER OFF BY LATE WEDNESDAY MORNING. TEMPS ACRS THE ENTIRE AREA WILL
BE NEAR NORMAL.
WEDNESDAY AND WEDNESDAY NIGHT...GENERAL UPPER LEVEL TROFINESS
LINGERS...AS WEAK SFC HIGH PRESSURE BUILDS IN ACRS THE AREA. HIGH
TEMPS WILL BE AT OR A CATEGORY BELOW NORMAL AND OVERNIGHT LOWS
AROUND NORMAL UNDER GENERALLY CLEAR SKIES.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AT 220 AM EST MONDAY...ON THURSDAY THE MEDIUM RANGE MODELS SHOW
SURFACE HIGH PRESSURE CENTERED OVER THE GULF COAST AT THE FLORIDA
PANHANDLE WHILE CUTTING OFF ANY MOISTURE FLOW TO OUR REGION. FAIRLY
VIGOROUS VORT MAXES CROSSING THE AREA BUT NO MOISTURE TO WORK WITH.
ON FRIDAY...THE SURFACE HIGH SHIFTS EAST TO FLORIDA AND FARTHER EAST
AND SOME MOISTURE FLOW STARTS FROM THE WESTERN GULF AS A SHORTWAVE
DROPS DOWN FROM THE NORTHERN MISS VALLEY AND OHIO VALLEY. THIS
SHORTWAVE REACHES THE APPALACHIANS FRIDAY NIGHT AND SOME NORTHWEST
FLOW MOISTURE ALIGNS ALONG THE UPSLOPE REGION ALONG THE TENNESSEE
AND NORTH CAROLINA BORDER. THE FAST MOVING SHORTWAVE HAS AN AXIS
NEAR THE WV / VA BORDER BY 12Z SATURDAY ON BOTH THE GFS AND ECMWF.
IF THERE IS ANY SNOW SHOWERS FOR THE NC MOUNTAINS NEAR THE TN
BORDER...THIS WILL BE BRIEF AND MAINLY IN THE WEE HOURS OF SATURDAY
ACCORDING TO THE CURRENT TIMING OF THE MODELS. THE LATEST ECMWF
JUST CAME IN AND MUCH DRIER WITH ONLY A HINT OF ANY PRECIP FAR
NORTHERN MOUNTAINS AROUND 12Z SATURDAY. THE ENERGY WITH THE
SHORTWAVE IS FARTHER NORTH WITH THIS EC RUN. AT THIS POINT...NOT
FEELING CONFIDENT AND LEAVING NO MORE THAN 14 POP...JUST BELOW
SLIGHT POPS.
WEAK HIGH PRESSURE CENTERED OVER OUR REGION SATURDAY NIGHT. RETURN
FLOW BEGINS OVER THE LOWER MISS VALLEY SATURDAY NIGHT AHEAD OF THE
NEXT SHORTWAVE. THIS NEXT SHORTWAVE IS QUITE DIFFERENT ON THE GFS
COMPARED TO THE ECMWF. THE GFS HAS A STRONG SHORTWAVE CROSSING
GREAT LAKES AND OHIO VALLEY SUNDAY AND LOWERING THICKNESS VALUES
SUNDAY NIGHT FOR OUR AREA...ESPECIALLY IN NC. VERY LITTLE MOISTURE
ON GFS. HOWEVER...THE ECMWF HAS A DEEP CUT OFF UPPER LOW CROSSING
MISSOURI LATE SUNDAY NIGHT WITH ASSOCIATED COLD FRONT REACHING OUR
AREA NEAR 12Z MONDAY WITH GOOD SOUTHERN FLOW FROM THE GULF. THIS
LATEST EC IS QUITE DIFFERENT FROM THE PREVIOUS RUN AND THE SUNDAY
NIGHT PERIOD IS THE EXTRA PERIOD THAT DOES NOT COUNT IN THE CURRENT
SEVEN DAY FORECAST. THUS WE WILL SEE AS THE TIME GETS CLOSER TO
THAT POINT.
TEMPERATURES WILL BE A FEW DEGREES ABOVE NORMAL WITH SLIGHT FALLS
WITH PASSING SHORTWAVES.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AT KCLT...HIGH PRESSURE WILL BUILD INTO THE REGION TODAY. WINDS WILL
START THE MORNING OUT OF THE NORTH...VEERING AROUND TO NORTHEAST IN
THE AFTN. A FEW GUSTS TO 18 TO 20 KTS ARE EXPECTED THIS MORNING.
WINDS WILL BECOME LIGHT FOR A TIME THIS EVENING...BEFORE TURNING OUT
OF THE ESE OVERNIGHT AS THE HIGH MOVES OFF THE COAST AND LOW
PRESSURE APPROACHES FROM THE SOUTH. THE RAPIDLY MOVING STORM SYSTEM
WILL BRING RAIN AND LOWERING CIGS INTO THE AIRFIELD AT THE VERY END
OF THE VALID PERIOD OF THE TAF.
AND ELSEWHERE...THE PROGRESSION OF THE RIDGE AND WIND SHIFTS WILL BE
SIMILAR TO THOSE MENTIONED FOR KCLT. TOWARD THE END OF THE
PERIOD...RAIN AND LOW CIGS WILL RAPIDLY SPREAD INTO THE REGION FROM
THE SOUTH. THE GUIDANCE DROPS CIGS INTO THE LIFR RANGE VERY QUICKLY
AT THE END OF THE TAF PERIOD. WITH THE LLVL DRY AIR IN PLACE THIS
MAY BE OVERDONE. LOW LEVEL WIND SHEAR IS LIKELY TO DEVELOP LATER
TONIGHT AS A ESE ORIENTED LLVL JET MOVES ACROSS THE REGION.
OUTLOOK...LOW PRES WILL MOVE N FROM THE W GULF MON NIGHT AND INTO
THE FORECAST AREA TUE...BRINGING WIDESPREAD PRECIPITATION AND IFR OR
LOWER CIG RESRICTIONS ON TUE. DRYING IS EXPECTED TUE NIGHT...WITH
LINGERING NW FLOW MOISTURE NEAR KAVL. CONDITIONS DRY OUT ACROSS THE
AREA MID TO LATE WEEK.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...DEO
NEAR TERM...MCAVOY
SHORT TERM...ARK
LONG TERM...DEO
AVIATION...MCAVOY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
612 AM EST MON DEC 26 2011
.SYNOPSIS...
A DEEPENING LOW PRESSURE SYSTEM IS EXPECTED TO TRACK NORTHEAST FROM
LOUISIANA TODAY AND REACH TENNESSEE AND KENTUCKY EARLY TUESDAY. HIGH
PRESSURE WILL BE BACK IN CONTROL FROM WEDNESDAY UNTIL THE WEEKEND
WHEN A COLD FRONT WILL APPROACH THE AREA FROM THE WEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 610 AM...THE ONLY SITE STILL REPORTING DENSE FOG IS
GREENWOOD...AND CONDITIONS SHOULD IMPROVE THERE SHORTLY.
THEREFORE...THE DENSE FOG ADVISORY WILL NOT BE EXTENDED. TWEAKED
TEMPS AND DEWPOINTS AS DOWNSLOPE MIXING AND DRYING IS CAUSING A
VARIETY OF TEMPS AND DEWPOINTS ACROSS THE AREA.
PREVIOUS DISCUSSION...
DENSE FOG AND LOW CLOUDS CONTINUES ACROSS THE CENTRAL AND EASTERN
PARTS OF THE UPSTATE AND THE EXTREME SRN PIEDMONT OF NORTH CAROLINA.
DRY AIR WILL CONTINUE TO WORK SLOWLY TO THE SOUTH...GRADUALLY MIXING
OUT THE FOG AND LOW CLOUDS. THE RUC AND NAM CONDENSATION PRESSURE
DEFICITS IMPLY LOW CLOUDS AND FOG ARE LIKELY TO PERSIST THE LONGEST
ACROSS GREENVILLE...SPARTANBURG AND LAURENS COUNTIES IN A WEAK LLVL
CONVERGENCE AXIS. WE HAVE A DENSE FOG ADVISORY OVER PARTS OF THE
AREA THROUGH 6 AM. IT WILL LIKELY NEED TO BE CANCELLED EARLY OVER
THE WESTERN UPSTATE AND NE GA...BUT IT STILL LOOKS GOOD FARTHER TO
THE EAST.
A STRONG UPPER LOW OVER WEST TEXAS THIS MORNING WILL EJECT QUICKLY
ACROSS THE LOWER MISSISSIPPI VALLEY TONIGHT AND LIFT ACROSS THE SRN
APPALACHIANS ON TUE AS AN OPEN WAVE. SFC CYCLOGENESIS WILL OCCUR
THIS AFTERNOON OVER THE NRN GULF...WITH THE LOW MOVING ACROSS THE
SRN APPS ON TUE. THE LATEST NAM AND GFS MODEL DATA IS A LITTLE
COLDER ACROSS THE NC MTNS TONIGHT. THE NAM HAS A LARGE AREA OF
1305-1310 METER 1000-850 MB THICKNESSES ACROSS THE SW AND CENTRAL
MTNS AT 0900 UTC...WHICH RETREAT UP ACROSS THE NRN MTNS BY 12 UTC.
NAM MODEL SOUNDINGS AT FRANKLIN AND CASHIERS IMPLY A PERIOD OF SLEET
AND FREEZING RAIN STARTING AFTER MIDNIGHT...WITH PCPN CHANGING TO
ALL RAIN TOWARD MORNING. THE GFS IS A LITTLE WARMER AND LOOKS TO BE
MAINLY LIQUID...WITH JUST A LITTLE SLEET AND A FEW PATCHES OF
FREEZING RAIN AT ONSET. IT STILL APPEARS THAT THE BULK OF THE
COOLING WITH THIS EVENT WILL BE DRIVEN BY OROGRAPHIC ASCENT AS A 60+
KT LLVL WARM SECTOR JET CROSSES THE MTNS. THIS SHOULD CONFINE
WINTRY PCPN TO SOUTH AND EAST REACHES OF THE MTNS...WITH DOWNSLOPE
HELPING TO WARM THE BNDRY LAYER CLOSER TO THE TN LINE. ALSO...NONE
OF THE MODELS IMPLY THAT WINTRY WX WILL HOLD ON ONCE THE HEAVIER
RAIN STARTS OWING TO A STRONG WARM NOSE UP AROUND H8. STILL...A
PERIOD OF LIGHT FREEZING RAIN AND SOME SLEET LOOKS LIKELY ACROSS
THE SW MTNS...AND ALSO ACROSS THE EASTERN ESCARPMENT OF THE BLUE
RIDGE UP IN THE NRN MTNS. AT THE MOST...THIS SHOULD BE A LOW END
ADVISORY LEVEL EVENT WITH ANY GLAZE CONFINED MAINLY TO ELEVATED
SFCS...AND IT WON/T AFFECT THE MTNS UNTIL WELL AFTER DARK TONIGHT.
THEREFORE...I/M GOING TO HOLD OFF ON ANY ADVISORIES WITH THIS
PACKAGE.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 315 AM MONDAY...THE MODELS ARE IN VERY GOOD AGREEMENT ON THE
POSITION OF THE UPPER SHORTWAVE AND SFC LOW PRESSURE AT 12Z TUESDAY.
AN IN SITU WEDGE WILL STILL BE IN PLACE ACRS THE CWFA...WITH SELY
850 MB WINDS OF 50-65 KTS ALOFT. VERY STRONG LLVL WAA AND MECHANICAL
LIFT WITH DEEP MOISTURE WILL BE AIDED BY DECENT QG FORCING AND UPPER
DIVERGENCE. SO A NEAR 100% POP TUESDAY MORNING SEEMS APPROPRIATE.
THERE ARE SOME DIFFERENCES AMONGST THE THERMAL PROFILES/SFC TEMPS
INVOF THE NC MTNS...HOWEVER...AS DYNAMICAL COOLING MAY LOCK IN
SUB-FREEZING TEMPS INVOF THE EAST-FACING SLOPES OF THE NRN MTNS/BLUE
RIDGE ESCARPMENT PAST DAYBREAK TUESDAY MORNING...WITH SOME
ADDITIONAL ICING POSSIBLE. ALL GUIDANCE HAS TEMPS WARMING ABOVE
FREEZING BY 15Z TUE...SO IT STILL LOOKS LIKE ANY TRAVEL PROBLEMS DUE
TO ICE SHUD BE OVER BY MIDDAY.
MIDDAY TUESDAY...THE LOW PRESSURE SYSTEM WILL QUICKLY LIFT
NORTHEASTWARD...WITH A PRIMARY LOW TRACKING ACRS THE TN/OH
VLYS...AND A TRIPLE POINT LOW TRACKING FROM CENTRAL GA TO CENTRAL NC
BY LATE AFTN. THE NAM/GFS/ECWMF ARE IN GOOD AGREEMENT ON THE GSP/CAE
CWFA BORDER AS AN APPROXIMATE TRACK OF THE TRIPLE POINT. SO INSTBY
LOOKS TO STAY SOUTH OF THE FA. THAT IS GOOD...BECAUSE HELICITY
VALUES WILL BE THRU THE ROOF...AND VERY LITTLE INSTBY WOULD BE
SUFFICIENT FOR A SMALL TORNADO/WIND THREAT. THE COLD/OCCLUDED FRONT
WILL CROSS FROM SW TO NE DURING THE AFTN HOURS...QUICKLY TAPERING
OFF POPS (EXCEPT FOR UPSLOPE ALONG TN/NC BORDER). STORM TOTAL QPF
LOOKS TO BE A SOLID 1-1.5" CWFA-WIDE...WITH 2-3" ALONG THE BLUE
RIDGE ESCARPMENT FROM HENDERSON COUNTY WEST. THERE COULD BE A FEW
HYDRO CONCERNS IN THOSE AREAS...BUT NOT WIDESPREAD ENUF TO WARRANT
ANY FLOOD WATCHES ATTM. WITH CLOUDS AND PRECIP...TEMPS WILL BE HELD
DOWN TO MAINLY MID-UPR 40S...EXCEPT ALONG SOUTHEAST EDGE NEAR THE
TMB/WEDGE BNDRY WHERE THEY WILL BE IN THE MID 50S OR HIGHER.
TUESDAY NIGHT...THERE WILL BE STRONG LLVL CAA ACRS THE FA IN THE
WAKE OF THE DEPARTING LOW...WITH GOOD NW FLOW UPSLOPE FORCING ALONG
THE TN/NC BORDER. BOTH THE NAM AND GFS IMPLY AT LEAST SCATTERED
SHOWER ACTIVITY...AND SNOW LEVELS SHUD FALL QUICKLY DURING THE
EVENING HOURS. SOME LOCATIONS MAY GET A QUICK INCH OR TWO
(ESPECIALLY ABOVE 3500 FT). THE SHOWER ACTIVITY LOOKS TO QUICKLY
TAPER OFF BY LATE WEDNESDAY MORNING. TEMPS ACRS THE ENTIRE AREA WILL
BE NEAR NORMAL.
WEDNESDAY AND WEDNESDAY NIGHT...GENERAL UPPER LEVEL TROFINESS
LINGERS...AS WEAK SFC HIGH PRESSURE BUILDS IN ACRS THE AREA. HIGH
TEMPS WILL BE AT OR A CATEGORY BELOW NORMAL AND OVERNIGHT LOWS
AROUND NORMAL UNDER GENERALLY CLEAR SKIES.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AT 220 AM EST MONDAY...ON THURSDAY THE MEDIUM RANGE MODELS SHOW
SURFACE HIGH PRESSURE CENTERED OVER THE GULF COAST AT THE FLORIDA
PANHANDLE WHILE CUTTING OFF ANY MOISTURE FLOW TO OUR REGION. FAIRLY
VIGOROUS VORT MAXES CROSSING THE AREA BUT NO MOISTURE TO WORK WITH.
ON FRIDAY...THE SURFACE HIGH SHIFTS EAST TO FLORIDA AND FARTHER EAST
AND SOME MOISTURE FLOW STARTS FROM THE WESTERN GULF AS A SHORTWAVE
DROPS DOWN FROM THE NORTHERN MISS VALLEY AND OHIO VALLEY. THIS
SHORTWAVE REACHES THE APPALACHIANS FRIDAY NIGHT AND SOME NORTHWEST
FLOW MOISTURE ALIGNS ALONG THE UPSLOPE REGION ALONG THE TENNESSEE
AND NORTH CAROLINA BORDER. THE FAST MOVING SHORTWAVE HAS AN AXIS
NEAR THE WV / VA BORDER BY 12Z SATURDAY ON BOTH THE GFS AND ECMWF.
IF THERE IS ANY SNOW SHOWERS FOR THE NC MOUNTAINS NEAR THE TN
BORDER...THIS WILL BE BRIEF AND MAINLY IN THE WEE HOURS OF SATURDAY
ACCORDING TO THE CURRENT TIMING OF THE MODELS. THE LATEST ECMWF
JUST CAME IN AND MUCH DRIER WITH ONLY A HINT OF ANY PRECIP FAR
NORTHERN MOUNTAINS AROUND 12Z SATURDAY. THE ENERGY WITH THE
SHORTWAVE IS FARTHER NORTH WITH THIS EC RUN. AT THIS POINT...NOT
FEELING CONFIDENT AND LEAVING NO MORE THAN 14 POP...JUST BELOW
SLIGHT POPS.
WEAK HIGH PRESSURE CENTERED OVER OUR REGION SATURDAY NIGHT. RETURN
FLOW BEGINS OVER THE LOWER MISS VALLEY SATURDAY NIGHT AHEAD OF THE
NEXT SHORTWAVE. THIS NEXT SHORTWAVE IS QUITE DIFFERENT ON THE GFS
COMPARED TO THE ECMWF. THE GFS HAS A STRONG SHORTWAVE CROSSING
GREAT LAKES AND OHIO VALLEY SUNDAY AND LOWERING THICKNESS VALUES
SUNDAY NIGHT FOR OUR AREA...ESPECIALLY IN NC. VERY LITTLE MOISTURE
ON GFS. HOWEVER...THE ECMWF HAS A DEEP CUT OFF UPPER LOW CROSSING
MISSOURI LATE SUNDAY NIGHT WITH ASSOCIATED COLD FRONT REACHING OUR
AREA NEAR 12Z MONDAY WITH GOOD SOUTHERN FLOW FROM THE GULF. THIS
LATEST EC IS QUITE DIFFERENT FROM THE PREVIOUS RUN AND THE SUNDAY
NIGHT PERIOD IS THE EXTRA PERIOD THAT DOES NOT COUNT IN THE CURRENT
SEVEN DAY FORECAST. THUS WE WILL SEE AS THE TIME GETS CLOSER TO
THAT POINT.
TEMPERATURES WILL BE A FEW DEGREES ABOVE NORMAL WITH SLIGHT FALLS
WITH PASSING SHORTWAVES.
&&
.AVIATION /11Z MONDAY THROUGH FRIDAY/...
AT KCLT...A SHARP DEWPOINT GRADIENT WAS LOCATED JUST TO THE
NORTHWEST OF THE AIRFIELD AT TAF ISSUANCE TIME. SOUTH OF THE BNDRY
WIDESPREAD DENSE FOG AND/OR VLIFR STRATUS HAS DEVELOPED. DRY AIR
WILL VERY SLOWLY PUSH TO THE SOUTH OVERNIGHT...BUT IT WILL BE A
COUPLE HOURS YET UNTIL THE DRY AIR WORKS IT/S WAY ACROSS THE
AIRFIELD WITH A WIND SHIFT TO THE NORTHWEST AND IMPROVING
CONDITIONS. SOME GUIDANCE TAKES EVEN LONGER TO BRING THE BNDRY
THROUGH...BUT BASED ON THE GUSTY WINDS AT KHKY AND 25 DEG DEWPOINT
AT KIPJ...I THINK THAT CONDITIONS WILL IMPROVE AT KCLT AFTER 0800
UTC.
AND ELSEWHERE...DRY AIR AND A WEAK COLD FRONT HAVE PUSHED THROUGH
KAVL AND KHKY WHICH WILL SEE NORTHWEST WINDS AND VFR CONDITIONS THE
REST OF THE NIGHT. OVER THE UPSTATE THE BNDRY HAS ONLY JUST MOVED
OFF THE ESCAPEMENT...AND IT WILL MOVE VERY SLOWLY...IF AT
ALL...OVER THE NEXT SEVERAL HOURS. DENSE FOG AND VLIFR CIGS HAVE
DEVELOPED IN THE MOIST AIR AHEAD OF THE BNDRY...AND THESE CONDITIONS
ARE EXPECTED TO PERSIST FOR THE NEXT 3 HRS OR SO AT THE THREE
UPSTATE AIRFIELDS. EVENTUALLY THE STRATUS AND FOG WILL BE PUSHED
SOUTH OF I-85...BUT A CONVERGENCE AXIS MAY HOLD IN LOW CIGS THROUGH
SUNRISE...ESPECIALLY AT KGMU AND KAND...WHICH IS WHAT I/VE DONE IN
THE TAFS. CONDITIONS THE REST OF THE DAY WILL BE GOOD WITH VFR
CONDITIONS AND LIGHT AND VARIABLE WINDS UNDER A RIDGE OF HIGH
PRESSURE.
OUTLOOK...LOW PRES WILL MOVE N FROM THE W GULF MON NIGHT AND INTO
THE FORECAST AREA TUE...BRINGING WIDESPREAD PRECIPITATION AND LOW
RESTRICTIONS. DRYING IS EXPECTED TUE NIGHT...WITH LINGERING NW FLOW
MOISTURE NEAR KAVL. CONDITIONS DRY OUT ACROSS THE AREA MID TO LATE
WEEK.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...DEO
NEAR TERM...MCAVOY
SHORT TERM...ARK
LONG TERM...DEO
AVIATION...MCAVOY
AREA FORECAST DISCUSSION
NWS GOODLAND KS
404 AM MST WED DEC 28 2011
.SYNOPSIS...
222 AM MST WED DEC 28 2011
LATEST SATELLITE IMAGERY AND RUC ANALYSIS SHOW AN UPPER LEVEL RIDGE
OVER THE WEST COAST...WITH AREAS OF CLOUDS AND PRECIPITATION MOVING
ALONG THE NORTHERN PERIPHERY. OVER THE HIGH PLAINS A SHORT WAVE
TROUGH WAS PROGRESSING SOUTHEAST INTO TEXAS. AT THE SURFACE A
TROUGH WAS MOVING THROUGH THE TRI-STATE AREA WITH SOUTHWEST WINDS
TURNING TO THE NORTHWEST BEHIND THE TROUGH.
JTL
&&
.SHORT TERM (TODAY-FRIDAY)...
222 AM MST WED DEC 28 2011
ABOVE NORMAL TEMPERATURES WILL BE THE FOCUS FOR THIS PERIOD.
TODAY...NORTHWEST FLOW WILL CONTINUE OVER THE AREA WITH A MINOR
SHORT WAVE TROUGH MOVING THROUGH THE FLOW DURING THE DAY. WITH THE
RIGHT EXIT REGION OF THE JET MOVING IN AND SOME MOISTURE MOVING
THROUGH THE FLOW...AM NOT ANTICIPATING ANYTHING MORE THAN SOME
CLOUDS. WINDS WILL BE BREEZY TODAY AS SOME OF THE STRONGER WINDS
ABOVE THE SURFACE ACCOMPANYING THE TROUGH ARE ABLE TO MIX DOWN.
TEMPERATURES WILL BE WARMER THAN YESTERDAY AS 850MB TEMPERATURES
WARM BEHIND THE TROUGH.
THURSDAY AND FRIDAY...A COUPLE OF SHORT WAVE TROUGHS WILL MOVE
THROUGH THE NORTHWEST FLOW...PLACING THE RIGHT ENTRANCE AND LEFT
EXIT REGIONS OF THE JET OVER THE TRI-STATE AREA. SOME 700-300MB
FRONTOGENESIS WILL MOVE OVER THE AREA WITH THESE TROUGHS. MODELS
DISAGREE WITH HOW MUCH MOISTURE IS PRESENT AS THE TROUGHS MOVE
THROUGH...ESPECIALLY FOR THE TROUGH COMING THROUGH FRIDAY MORNING.
SREF PRECIPITATION PROBABILITIES ARE ZERO WHILE THE GEFS DOES SHOW
A SMALL CHANCE FOR SOME MINIMAL PRECIPITATION IN THE
BENKELMAN...MCCOOK AND OBERLIN AREA. WITH SUCH DISAGREEMENT AMONG
MODELS...WILL LEAVE FORECAST DRY FOR NOW.
WINDS WILL STRENGTHEN THURSDAY AS STRONG UPPER LEVEL WINDS
ACCOMPANY THE TROUGH THROUGH THE AREA AND ARE ABLE TO MIX TO THE
SURFACE. CURRENTLY LOOKS LIKE AREAS NORTH OF HIGHWAY 36 WILL HAVE
THE BEST MIXING AND STRONGEST WINDS...WITH GUSTS UP TO 35 MPH
POSSIBLE. THE WINDS WILL DECREASE AT SUNSET. FRIDAY WINDS WILL BE
LIGHT AS A SURFACE HIGH PRESSURE MOVES INTO THE AREA AHEAD OF A
DEVELOPING SURFACE TROUGH OVER COLORADO.
TEMPERATURE-WISE THURSDAY WILL BE THE WARMEST...WITH HIGHS
REACHING THE LOWER 60S THANKS TO 850MB TEMPERATURES WARMING AS THE
TROUGH MOVES THROUGH. FRIDAY TEMPERATURES WILL BE A FEW DEGREES
COOLER AS COOLER AIR BEHIND THE TROUGH FROM FRIDAY MORNING MOVES
INTO THE AREA.
JTL
.LONG TERM (SATURDAY-TUESDAY)...
222 AM MST WED DEC 28 2011
NEW ECMWF IS MORE IN LINE WITH THE GFS SATURDAY BRINGING A
SHORTWAVE TROUGH AND COLD FRONT THROUGH THE FORECAST AREA.
DEPENDING ON THE TIMING OF THE FRONT...TEMPERATURES MAY WARM
NICELY IN THE MORNING. CURRENT PROJECTIONS OF FRONTAL PASSAGE IN
THE AFTERNOON...THOUGH...WILL LIMIT TOO MUCH WARMING...AND WILL
CONTINUE WITH HIGH TEMPERATURES IN THE LOWER TO MID 50S. ECMWF
CONTINUES TO DEPICT LIGHT PRECIPITATION SATURDAY NIGHT OVER THE
NORTHERN SECTION OF AREA...BUT AGREE WITH OTHER MODELS ABOUT THE
LIMITED AMOUNT OF MOISTURE SO WILL CONTINUE WITH A DRY FORECAST.
STRONG 500 MB RIDGE WILL THEN BUILD OVER THE WESTERN UNITED
STATES BEGINNING SUNDAY AND CONTINUING THROUGH THE EARLY PART OF
NEXT WEEK. THE QUESTION WILL BE HOW FAR EAST THE RIDGE AXIS MOVES
AND HOW STRONG THE HEIGHT RISES WILL BE. THE ECMWF IS SLIGHTLY
STRONGER WITH THE RIDGE AXIS...BUT ALSO FURTHER WEST OF THE GFS.
THIS PLACES STRONG NORTH TRAJECTORIES OVER THE AREA MONDAY FOR
SOME COLD AIR ADVECTION. THE GFS IS FURTHER EAST AND WOULD SUPPORT
WARMER TEMPERATURES. REGARDLESS...BOTH MODELS PROG 500 MB HEIGHTS
OVER 576 METERS BY TUESDAY FOR ABOVE NORMAL TEMPERATURES AND
CONTINUED DRY.
&&
.AVIATION...
404 AM MST WED DEC 28 2011
FOR THE 12Z TAFS...VFR CONDITIONS WILL CONTINUE AT KGLD/KMCK THE
NEXT 24 HOURS. SURFACE WINDS WILL GENERALLY BE 5-15 KNOTS...THOUGH
A FEW HIGHER GUSTS MAY OCCUR AT KGLD FROM 19Z-23Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
623 AM EST WED DEC 28 2011
UPDATED AVIATION DISCUSSION FOR 12Z TAFS
.SYNOPSIS...
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
NE CANADA INTO ERN GREAT LAKES AND A FLAT RIDGE OVER THE WEST
RESULTING IN NW FLOW FROM THE CANADIAN PRAIRIE THROUGH THE WRN GREAT
LAKES. A SHEARED UPSTREAM SHORTWAVE TROUGH WAS MOVING INTO MANITOBA
WHILE ANOTHER IN THE FAST WRLY FLOW OFF THE NE PACIFIC WAS LOCATED
OVER SRN BC. AT THE SFC...A RIDGE EXTENDED FROM NRN ONTARIO INTO WRN
WI LEAVING NRLY FLOW ACROSS LAKE SUPERIOR. 850 MB TEMPS AROUND -15C
PROVIDED PLENTY OF INSTABILITY FOR LINGERING LES EVEN THROUGH VERY
DRY AIR UPSTREAM AND INVERSION HEIGHTS DOWN TO AROUND 3K-4K FT.
&&
.DISCUSSION...
TODAY...EXPECT THAT THE LES WILL DIMINISH THIS MORNING AND END BY
THIS AFTERNOON AS THE RIDGE MOVES ACROSS UPPER MICHIGAN AND WINDS
BECOME OFFSHORE. ANY ACCUMULATIONS WITH SCT -SHSN INTO THE N CNTRL
CWA THIS MORNING SHOULD AMOUNT TO LESS THAN AN INCH. RETURN SRLY
FLOW WILL ALLOW MAX TEMPS TO REBOUND INTO THE UPPER TEENS AND LOWER
20S.
TONIGHT INTO THU...MODELS SUGGEST THAT THE THE MID TO UPPER LEVEL
FORCING WITH THE COMBINATION OF THE MANITOBA AND BC SHORTWAVES
PASSING TO THE NORTH AND SOUTH OF UPPER MI WILL BE RELATIVELY
MODEST. HOWEVER...AN AREA OF 285K-290K ISENTROPIC LIFT NORTH OF THE
850 MB LOW WILL SUPPORT WIDESPREAD LIGHT SNOW...MAINLY BTWN 06Z-18Z.
WITH 2G-3G/KG AVBL...CONSENSUS QPF VALUES IN THE 0.1 TO 0.2...AND
SNOW WATER RATIO VALUES NEAR 15/1...PREVIOUS FCST OF 1 TO 3 INCHES
LOOKS ON TRACK.
THERE IS GREATER UNCERTAINTY WITH THE POTENTIAL FOR HIGHER LAKE
ENHANCED SNOW AMOUNTS WITH SRLY FLOW OFF OF LAKE MICHIGAN. THE HPC
AND LCLY RUN HIGH RES WRF/ARW AS WELL AS THE CANADIAN REGIONAL GEM
SUGGEST THAT A BAND MAY DEVELOP INTO WRN MACKINAC COUNTY LATE
TONIGHT INTO EARLY THU AIDED BY LEVEL LEVEL CONV NEAR THE NW LOWER
MI SHORE. THE BAND MAY SHIFT FARTHER WEST INTO SRN LUCE AND SRN
SCHOOLCRAFT COUNTIES AS WINDS BACK IN RESPONSE TO THE WEAK SFC LOW
MOVING TOWARD NRN LAKE MICHIGAN. ADDITIONAL SNOWFALL AMOUNTS OF
SEVERAL INCHES COULD PUSH OVERALL AMOUNTS INTO THE ADVY CATEGORY IF
THE BANDS DEVELOP AND PERSIST LONG ENOUGH AT ANY LOCATION.
HOWEVER...CONFIDENCE IS BELOW AVERAGE WITH THESE DETAILS.
THU NIGHT INTO FRI...LEFT OVER LIGHT SNOW OVER THE ERN PORTION OF
THE CWA WILL GRADUALLY SLIDE OFF TO THE EAST AS WEAKER ISENTROPIC
LIFT AND FGEN EXIT THE AREA. THE PATH OF THE NEXT SHORTWAVE REMAINS
FAR ENOUGH SOUTH...PER GFS/ECMWF SO THAT FRI WILL REMAIN MAINLY DRY.
SO...ONLY SLIGHT CHANCE POPS WERE INCLUDED.
SAT THROUGH TUE...A PROGRESSIVE MID LEVEL TROUGH MOVES INTO THE
PLAINS BRINGING WAA SAT. WITH LITTLE MOISTURE AVBL...LITTLE/NO
MEASURABLE PCPN IS EXPECTED. THE GFS HAS TRENDED TOWARD THE
GEM/ECMWF WITH TRANSITION TOWARD A MORE AMPLIFIED/MERIDIONAL PATTERN
BY LATE SUN INTO MON. AN INFLUX OF COLD AIR (850 MB TEMPS DOWN INTO
THE -17C TO -20C RANGE) BEHIND A COLD FRONT LATE SUN WITH DEEP
MOISTURE AVAILABLE SHOULD BRING LES TO LOCATIONS FAVORED BY NW TO N
FLOW TIL RIDING MOVES BACK IN BY TUE.
&&
.AVIATION /FOR THE 12Z TAF ISSUANCE/...
EXPECT LINGERING LES TO WANE THIS MORNING AS THE FLOW BECOMES MORE
ANTICYCLONIC AND VERY DRY AIR UPSTREAM OF LAKE SUPERIOR HAS AN
IMPACT. BUT WITH LINGERING LOW INVERSION BASE AND VERY CHILLY
AIRMASS PASSING OVER LAKE SUPERIOR...EXPECT MVFR CIGS TO LINGER INTO
THIS MORNING. AFTER THE LOW CLOUDS BREAK UP...VFR CONDITIONS WILL
THEN PREVAIL THROUGH MUCH OF THE DAY. ANOTHER BAND OF THICKER
CLOUDS/-SN WILL ARRIVE TOWARD EVENING WITH LOW END VFR/HIGH END MVFR
CONDITIONS. THE BEST CHANCE FOR THE MVFR CIGS WILL BE AT THE FARTHER
N CMX LOCATION.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
AS HIGH PRESSURE MOVES OVER LAKE SUPERIOR TODAY...WINDS WILL
DECREASE AND BECOME MORE SOUTHERLY THROUGH THE DAY. THE NEXT CHANCE
FOR SIGNIFICANT WINDS WILL COME OVER THE WEEKEND AS A LOW PRESSURE
SYSTEM MOVES NORTH OF LAKE SUPERIOR. THE STRONGEST WINDS WILL COME
ON SUNDAY FROM THE NW...AND MAY REACH GALE FORCE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
DISCUSSION...JLB
AVIATION...TITUS
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
552 AM EST WED DEC 28 2011
.SYNOPSIS...
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
NE CANADA INTO ERN GREAT LAKES AND A FLAT RIDGE OVER THE WEST
RESULTING IN NW FLOW FROM THE CANADIAN PRAIRIE THROUGH THE WRN GREAT
LAKES. A SHEARED UPSTREAM SHORTWAVE TROUGH WAS MOVING INTO MANITOBA
WHILE ANOTHER IN THE FAST WRLY FLOW OFF THE NE PACIFIC WAS LOCATED
OVER SRN BC. AT THE SFC...A RIDGE EXTENDED FROM NRN ONTARIO INTO WRN
WI LEAVING NRLY FLOW ACROSS LAKE SUPERIOR. 850 MB TEMPS AROUND -15C
PROVIDED PLENTY OF INSTABILITY FOR LINGERING LES EVEN THROUGH VERY
DRY AIR UPSTREAM AND INVERSION HEIGHTS DOWN TO AROUND 3K-4K FT.
&&
.DISCUSSION...
TODAY...EXPECT THAT THE LES WILL DIMINISH THIS MORNING AND END BY
THIS AFTERNOON AS THE RIDGE MOVES ACROSS UPPER MICHIGAN AND WINDS
BECOME OFFSHORE. ANY ACCUMULATIONS WITH SCT -SHSN INTO THE N CNTRL
CWA THIS MORNING SHOULD AMOUNT TO LESS THAN AN INCH. RETURN SRLY
FLOW WILL ALLOW MAX TEMPS TO REBOUND INTO THE UPPER TEENS AND LOWER
20S.
TONIGHT INTO THU...MODELS SUGGEST THAT THE THE MID TO UPPER LEVEL
FORCING WITH THE COMBINATION OF THE MANITOBA AND BC SHORTWAVES
PASSING TO THE NORTH AND SOUTH OF UPPER MI WILL BE RELATIVELY
MODEST. HOWEVER...AN AREA OF 285K-290K ISENTROPIC LIFT NORTH OF THE
850 MB LOW WILL SUPPORT WIDESPREAD LIGHT SNOW...MAINLY BTWN 06Z-18Z.
WITH 2G-3G/KG AVBL...CONSENSUS QPF VALUES IN THE 0.1 TO 0.2...AND
SNOW WATER RATIO VALUES NEAR 15/1...PREVIOUS FCST OF 1 TO 3 INCHES
LOOKS ON TRACK.
THERE IS GREATER UNCERTAINTY WITH THE POTENTIAL FOR HIGHER LAKE
ENHANCED SNOW AMOUNTS WITH SRLY FLOW OFF OF LAKE MICHIGAN. THE HPC
AND LCLY RUN HIGH RES WRF/ARW AS WELL AS THE CANADIAN REGIONAL GEM
SUGGEST THAT A BAND MAY DEVELOP INTO WRN MACKINAC COUNTY LATE
TONIGHT INTO EARLY THU AIDED BY LEVEL LEVEL CONV NEAR THE NW LOWER
MI SHORE. THE BAND MAY SHIFT FARTHER WEST INTO SRN LUCE AND SRN
SCHOOLCRAFT COUNTIES AS WINDS BACK IN RESPONSE TO THE WEAK SFC LOW
MOVING TOWARD NRN LAKE MICHIGAN. ADDITIONAL SNOWFALL AMOUNTS OF
SEVERAL INCHES COULD PUSH OVERALL AMOUNTS INTO THE ADVY CATEGORY IF
THE BANDS DEVELOP AND PERSIST LONG ENOUGH AT ANY LOCATION.
HOWEVER...CONFIDENCE IS BELOW AVERAGE WITH THESE DETAILS.
THU NIGHT INTO FRI...LEFT OVER LIGHT SNOW OVER THE ERN PORTION OF
THE CWA WILL GRADUALLY SLIDE OFF TO THE EAST AS WEAKER ISENTROPIC
LIFT AND FGEN EXIT THE AREA. THE PATH OF THE NEXT SHORTWAVE REMAINS
FAR ENOUGH SOUTH...PER GFS/ECMWF SO THAT FRI WILL REMAIN MAINLY DRY.
SO...ONLY SLIGHT CHANCE POPS WERE INCLUDED.
SAT THROUGH TUE...A PROGRESSIVE MID LEVEL TROUGH MOVES INTO THE
PLAINS BRINGING WAA SAT. WITH LITTLE MOISTURE AVBL...LITTLE/NO
MEASURABLE PCPN IS EXPECTED. THE GFS HAS TRENDED TOWARD THE
GEM/ECMWF WITH TRANSITION TOWARD A MORE AMPLIFIED/MERIDIONAL PATTERN
BY LATE SUN INTO MON. AN INFLUX OF COLD AIR (850 MB TEMPS DOWN INTO
THE -17C TO -20C RANGE) BEHIND A COLD FRONT LATE SUN WITH DEEP
MOISTURE AVAILABLE SHOULD BRING LES TO LOCATIONS FAVORED BY NW TO N
FLOW TIL RIDING MOVES BACK IN BY TUE.
&&
.AVIATION /FOR THE 06Z TAF ISSUANCE/...
EXPECT LINGERING LES TO WANE EARLY THIS MRNG AS THE FLOW BECOMES
MORE ACYC AND VERY DRY AIR UPSTREAM OF LK SUP HAS AN IMPACT. BUT
WITH LINGERING LO INVRN BASE AND VERY CHILLY AIRMASS PASSING OVER LK
SUP...EXPECT MVFR CIGS TO LINGER THRU SUNRISE. THE CLDS MAY BREAK UP
A BIT EARLIER AT IWD CLOSER TO INCOMING HI PRES RDG. AFT THE LO CLDS
BREAK UP...VFR CONDITIONS WL THEN PREVAIL THRU MUCH OF THE DAY.
ANOTHER BAND OF THICKER CLDS/-SN WL ARRIVE TOWARD EVNG WITH LO END
VFR/HI END MVFR CONDITIONS. THE BEST CHC FOR THE MVFR CIGS WL BE AT
THE FARTHER N CMX LOCATION.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
AS HIGH PRESSURE MOVES OVER LAKE SUPERIOR TODAY...WINDS WILL
DECREASE AND BECOME MORE SOUTHERLY THROUGH THE DAY. THE NEXT CHANCE
FOR SIGNIFICANT WINDS WILL COME OVER THE WEEKEND AS A LOW PRESSURE
SYSTEM MOVES NORTH OF LAKE SUPERIOR. THE STRONGEST WINDS WILL COME
ON SUNDAY FROM THE NW...AND MAY REACH GALE FORCE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
DISCUSSION...JLB
AVIATION...KC
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS DULUTH MN
553 AM CST WED DEC 28 2011
.AVIATION [12Z TAF ISSUANCE]...
A SHORTWAVE MOVING THROUGH MANITOBA AND THE NORTHERN PLAINS WILL
BRING BKN/OVC MVFR CEILINGS TO NORTHEASTERN MINNESOTA AND
NORTHWESTERN WISCONSIN THIS MORNING. THERE WILL BE A BRIEF THREE TO
FOUR HOUR PERIOD OF LIGHT SNOWFALL WITH THIS SHORTWAVE PASSAGE.
THERE MAY BE PERIODS OF MVFR VIS WITH THE SNOW. MVFR OR LOW END VFR
CIGS WILL LIKELY REMAIN THROUGH THIS AFTERNOON...BUT THERE IS A
CHANCE OF SOME CLEARING. A CANADIAN CLIPPER WILL SWING THROUGH
CENTRAL MINNESOTA TONIGHT. IT WILL PROLONG MVFR CIGS THROUGH TONIGHT
AND BRING MORE LIGHT SNOW. MVFR VSBYS ARE POSSIBLE WITH THE SNOW.
LIGHT WINDS ARE EXPECTED THROUGH TOMORROW MORNING.
&&
.PREV DISCUSSION... /ISSUED 356 AM CST WED DEC 28 2011/
SHORT TERM...THE MAIN FORECAST CONCERN IN THE SHORT TERM IS THE
AMOUNT AND LOCATION OF ACCUMULATING SNOWFALL TODAY THROUGH TONIGHT.
AT 330 AM...CLOUDS WERE INCREASING AHEAD OF A WEAK SHORTWAVE AND
UP[PER LEVEL JET MAX TRAVERSING ACROSS MN. STRONG LOW LEVEL WAA
AND THETA-E ADVECTION WAS HELPING TO GENERATE LIGHT SNOW ACROSS
WESTERN MN DESPITE INITIALLY DRY LOW LEVEL AIR. THE HRRR RAPID
REFRESH WAS DEPICTING THE AREA OF CLOUDS/LIGHT SNOW FAIRLY WELL.
THE SHORTWAVE AND 100+ KNOT UPPER LEVEL JET MAX WILL CONTINUE TO
PUSH ACROSS THE NORTHLAND TODAY...PUSHING INTO THE WESTERN GREAT
LAKES BY THIS AFTERNOON. THE LATEST HRRR ACTUALLY SHOWS THE
RETURNS DIMINISHING FOR A TIME THIS EARLY MORNING...BEFORE
INCREASING A BIT AGAIN AS THEY REACH NE MN LATER IN THE MORNING.
THINK THERE IS A CHANCE FOR ABOUT A HALF INCH OF SNOWFALL IN SPOTS
TODAY. COULD SEE A BIT MORE ALONG THE SAWTOOTH MOUNTAINS OF THE
NORTH SHORE...AS WINDS COME AROUND TO THE EAST AND SUPPORT LAKE
EFFECT SNOW SHOWERS.
A STRONGER SYSTEM WILL MOVE IN TONIGHT...AND QUICKLY EXIT THE
REGION ON THURSDAY. HAVE SHIFTED THE FOCUS FOR ACCUMULATING
SNOWFALL A BIT TO THE SOUTH BASED ON THE LATEST 00Z MODEL RUNS.
CURRENT THINKING IS THAT THERE WILL BE A STRIPE OF 1 TO 3 INCHES
FROM THE NORTHERN BRAINERD LAKES REGION...THROUGH THE TWIN PORTS
AND INTO NW WI. ALSO CANNOT RULE OUT A NARROW STRIPE OF 2 TO 4
INCHES OR POSSIBLY A BIT MORE AS THE SYSTEM DROPS TO THE SOUTHEAST
AND LAYS DOWN A SWATH OF ACCUMULATING SNOWFALL. THE NORTH SHORE
SHOULD ALSO SEE HIGHER AMOUNTS DUE TO LAKE EFFECT/LAKE
ENHANCEMENT. IN TERMS OF SURFACE LOW PRESSURE...THE MODELS ARE
FAIRLY SIMILAR...BUT QPF AMOUNTS AND LOCATION DO VARY BETWEEN THE
ECMWF/NAM/GFS AND GEM. WILL TAKE A CONSENSUS SOLUTION. MAY NEED TO
BUMP UP AMOUNTS IN LATER FORECAST PACKAGES. IN THE
GRIDS...CURRENTLY HAVE AMOUNTS SIMILAR TO WHAT IS MENTIONED ABOVE.
THINK THE SYSTEM WILL BE FAIRLY EFFICIENT AT RINGING OUT AVAILABLE
MOISTURE.
THE LOW PRESSURE SYSTEM WILL MOVE OUT OF THE REGION ON
THURSDAY...WITH A BIT OF A BREAK BEFORE THE NEXT SYSTEM ARRIVES
THURSDAY NIGHT. THE NAM SOLUTION WOULD SUPPORT HIGHER POPS FOR
THURSDAY NIGHT...BUT THE ECMWF/GFS KEEP THE ACCUMULATING SNOW
GENERALLY WEST AND SOUTH OF THE CWA.
LONG TERM...FRIDAY THROUGH TUESDAY.
FRIDAY...THE LONG TERM PERIOD BEGINS WITH LOW CHANCES OF
SNOWFALL...MAINLY DUE TO THE GFS SHOWING A TROUGH MOVING THROUGH
THE NORTHLAND. IT LOOKS LIKE A RIDGE WILL MOVE INTO THE REGION
FRIDAY NIGHT WITH SOUTHERLY WINDS DEVELOPING BY SATURDAY MORNING.
SATURDAY...IT LOOKS LIKE A RELATIVELY WARM DAY. SOUTHWESTERLY WINDS
WILL DEVELOP AS A LOW PRESSURE SYSTEM MOVES FROM CENTRAL MANITOBA TO
WESTERN ONTARIO. THERE MAY BE SOME LIGHT PCPN ACROSS THE NORTHLAND.
CONSIDERING THE WARMER SURFACE TEMPERATURES AND TEMPERATURES
ALOFT...FORECASTED A POSSIBLE MIXTURE OF RAIN AND SNOW. PLUS...MODEL
SOUNDINGS GENERALLY HAD SATURATION ALOFT TO ONLY ABOUT -5 DEGREES
CELSIUS OR LESS UNTIL LATER IN THE EVENING WHEN THE COLDER AIR IS
USHERED INTO THE NORTHLAND. SO WOULD THINK THE PCPN WOULD LIKELY
TURN BACK TO SNOW SATURDAY NIGHT.
SUNDAY AND MONDAY...THE BEGINNING OF NEXT WEEK SHOULD START OFF
COLD. IT LOOKS LIKE THE POSSIBILITY OF LINGERING SYNOPTIC SNOW
ACROSS THE NORTHLAND...AS WELL AS LAKE EFFECT SNOWFALL ALONG PARTS
OF THE SOUTH SHORE. THE MODELS INDICATE VERY COLD 850 HPA WILL WRAP
INTO THE NORTHLAND...AS LOW AS -16 DEGREES CELSIUS. THIS SHOULD MAKE
FOR A SOLID TEMPERATURE DIFFERENCE BETWEEN 850 HPA AND THE LAKE
SURFACE TEMPERATURE...WHICH IS AROUND 4 DEGREES CELSIUS.
&&
.POINT TEMPS/POPS...
DLH 27 19 29 21 / 30 70 20 20
INL 26 12 26 15 / 30 30 10 20
BRD 32 25 33 24 / 20 60 20 30
HYR 28 20 32 23 / 20 70 30 30
ASX 29 20 33 24 / 20 70 30 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
AVIATION...GROCHOCINSKI
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
700 AM EST WED DEC 28 2011
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION TODAY AND LINGER THROUGH
FRIDAY. A COLD FRONT WILL PUSH THROUGH THE AREA FRIDAY NIGHT.
ANOTHER AREA OF HIGH PRESSURE WILL BUILD IN THIS WEEKEND. A STRONG
COLD FRONT WILL PUSH THROUGH SUNDAY NIGHT OR EARLY MONDAY OF NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 7 AM WED...CURRENT H20 VAPOR ANALYSIS INDICATING H7 TROUGH
AXIS SWINGING THROUGH E NC AND COASTAL WATERS. CAA CONTINUES TO
KEEP WINDS IN THE 10 TO 15 KT RANGE AT THE SFC EARLY THIS MORNING.
RUC ANALYSIS INDICATES LARGEST PRES RISES CONTINUING THROUGH MID
MORNING TODAY...WHICH IN CONJUNCTION WITH EFFICIENT UNIDIRECTIONAL
SHEAR IN THE BL WILL BRING DOWN HIGHER WINDS ALOFT IN THE FORM OF
GUSTS IN THE 20 TO 25 KT RANGE AT THE SFC. GRADIENT WILL REMAIN
STRONGEST ACROSS THE OBX AND WITH GOOD MIXING...WILL LEAVE THE
CURRENT WIND ADVISORY IN EFFECT...THOUGH CRITERIA WILL BE
MARGINAL. GRADIENT RELAXES BY THIS AFTERNOON AND WINDS WILL
DIMINISH IN RESPONSE.
FOR TEMP FCST...USED MODEL BLEND OF THE BIAS CORRECTED GFS/SREF
GRIDS AND 1000-850 MB THICKNESSES TO YIELD HIGHS GENERALLY IN THE
LOWER 50S ACROSS E NC. IT WILL FEEL QUITE A BIT COOLER DUE TO THE
BRISK WESTERLY WINDS HOWEVER. SKIES WILL BE MOSTLY SUNNY AS DEEP
LAYER DRYING CONTINUES THROUGH THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
AS OF 3 AM WED...GUSTY WINDS OF TODAY WILL DIMINISH QUITE RAPIDLY
TOWARDS SUNSET THIS EVENING AS PRES GRADIENT WEAKENS AND DRY HIGH
PRES BEGINS BUILDING IN FROM THE WEST. TD VALS WILL PLUMMET
THROUGH THE 20S AND WITH CLEAR SKIES AND CALM WINDS OVERNIGHT...
MIN TEMPS WILL FOLLOW SUIT AND SETTLE INTO THE 20S FOR AREAS AWAY
FROM THE IMMEDIATE COAST. NW WINDS WILL CONTINUE FOR THE OBX WITH
LOWS HERE IN THE 30S.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 300 AM WED...NO SIGNIFICANT CHANGES TO PREVIOUS FCST DURING
PERIOD. MODELS IN DECENT AGREEMENT WITH NEAR ZONAL FLOW PATTERN INTO
EARLY NEXT WEEK...WITH STRONGEST NORTHERN STREAM SHRT WV MOVING
THROUGH SAT. GULFMEX WILL BE CUTOFF SO JUST A DRY FRONTAL PASSAGE
EXPECTED AT SFC WITH THIS SYSTEM. DID ADJUST TEMPS THU-FRI BASED ON
LATEST MOS GDNC BLEND.
MODELS CONTINUE TO INDICATE UPR TROFFING OVER ERN US MON INTO TUE.
00Z ECMWF MORE PROGRESSIVE THAN PREVIOUS RUNS WITH TROF...WITH SFC
LOW DEVELOPMENT FARTHER OFFSHORE MIDWEEK...BUT LIKELY OVERDONE WITH
DEPTH OF TROF PER EXTENDED PROG DISCUSSIONS. MODELS DO CONTINUE TO
INDICATE ENOUGH DYNAMICS WITH UPR SYSTEM TO KEEP 20 POPS FOR SUN
NIGHT AND MONDAY.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 7 AM WED...PRES RISES WILL BE GREATEST THROUGH THE MORNING
AND WITH GOOD MIXING TODAY...WILL SEE WINDS GUSTING INTO THE 20 TO
25 KT RANGE FOR ALL TERMINALS. SKIES WILL BE SUNNY AS DRY HIGH
PRES BUILDS IN. WINDS DIMINISH VERY QUICKLY TOWARDS SUNSET AS HIGH
BUILDS IN...GRADIENT RELAXES AND CAA SUBSIDES. DO NOT EXPECT FOG
OR BR AS BNDRY LAYER WILL BE QUITE DRY WITH TD VALS IN THE LOW TO
MID 20S OVERNIGHT...THOUGH TYPICAL LOCALES SUCH AS KPGV WILL HAVE
TO BE MONITORED FOR BR DEVELOPMENT.
LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 300 AM WED...VFR THROUGH THE PERIOD. ISOLATED SHOWERS
POSSIBLE SUNDAY NIGHT WITH A STONGER UPR LEVEL TROF.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/
AS OF 7 AM WED...CURRENT SFC OBS INDICATING MARGINAL GALE
CONDITIONS OCCURING OFF NC COAST. FRYING PAN BUOY GUSTING BETWEEN
35 AND 40 KT THROGUH THIS MORNING...AND A SHIP 30 MI SE CAPE
HATTERAS REPORTING SUSTAINED WINDS OF 30 KT. NEAR TERM GUIDANCE
INDICATES GREATEST ISALLOBARIC PRES RISES OCCURRING RIGHT NOW AS
TROUGH AXIS IS SWINGING THROUGH THE COASTAL WATERS. THIS IS IN
LINE WITH HRRR WINDS GUSTS APPROACHING GALE FORCE THROUGH ABOUT
THIS TIME. WINDS WILL OCCASIONALLY GUST TO GALE FORCE OVER EASTERN
PORTIONS OF PAMLICO SOUND AS WELL THROUGH MID MORNING. 700 MB
TROUGH AXIS WILL EXIT THE NC COASTAL WATERS THIS MORNING...AND
WITH DEPARTING THOUGH DEEPENING LOW ACROSS NEW ENGLAND...WINDS
WILL BEGIN TO ABATE. CAA HOWEVER WILL CONTINUE TO PRODUCE SCA WIND
GUSTS THROUGH MUCH OF TODAY...AND WILL HAVE TO REPLACE GALES WITH
SCA AFTER THEIR SCHEDULED EXPIRATION TIMES OF 15Z. SEAS WILL ALSO
REMAIN ABOVE 6 FT FOR THE REMAINDER OF TODAY...HIGHEST THROUGH
THIS MORNING.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 300 AM WED...BRIEF PERIOD OF LIGHTER WINDS AND SEAS THU
MORNING...THEN GRADIENT BETWEEN LOW PRESSURE MOVING ACROSS N OF AREA
AND HIGH PRESSURE TO S WILL PRODUCE INCREASING W TO SW WINDS THU
NIGHT INTO FRI NIGHT...WITH MARGINAL SCA CONDITIONS PSBL FOR OUTER
PORTIONS OF WATERS. WINDS BECOMING NRLY LATE SAT FOLLOWING DRY
FRONTAL PASSAGE...WITH SPEEDS DECREASING SAT NIGHT WITH HIGH PRES
BUILDING IN FROM W. WINDS WILL VEER QUICKLY BACK TO SW SUN AS HIGH
PRES MOVES OFFSHORE. BLEND OF WW3...LOCAL SWAN AND PREVIOUS FCST
USED FOR SEAS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...WIND ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR NCZ103-104.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR AMZ130-
135.
GALE WARNING UNTIL 10 AM EST THIS MORNING FOR AMZ150-152-154-
156-158.
&&
$$
SYNOPSIS...TL
NEAR TERM...TL
SHORT TERM...TL
LONG TERM...JBM
AVIATION...TL/JBM
MARINE...TL/JBM
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
708 AM EST WED DEC 28 2011
.SYNOPSIS...
BLUSTERY WEST WINDS WILL CREATE SOME LAKE EFFECT SNOW AND
FLURRIES TODAY...BUT THE SNOW SHOWERS WILL TAPER OFF THROUGH THE
DAY. WEAK HIGH PRESSURE TONIGHT WILL BE PUSHED TO THE SOUTH AS A
COUPLE OF ALBERTA CLIPPERS MOVE ACROSS THE GREAT LAKES THURSDAY
NIGHT AND FRIDAY...AND COULD PRODUCE A FEW INCHES OF SNOW IN THE
NORTH AND WEST. FAIR WEATHER SHOULD FOLLOW FOR SATURDAY.
&&
.NEAR TERM /UNTIL NOON TODAY/...
TIGHT P-GRADIENT AROUND THE DEPARTED STORM WILL CONTINUE TO CREATE
GUSTY WINDS OVER THE STATE. BUFKIT MOMENTUM TRANSFER VALUES FROM
NAM AND RUC SHOW GUSTS WILL PROBABLY TOP OUT IN THE M/U30KT
RANGE...BUT RUN THROUGH MUCH OF THE DAY. LAST VESTIGE OF THE UPPER
LOW APPEARS TO HAVE JUST PASSED KELZ AND KUNV. RADAR SHOWS SNOW IN
VERY LONG BUT ALSO VERY THIN/NARROW BANDS. VERY FEW IFR OBS TO BE
FOUND. THE GUSTY WINDS WILL BE CREATING A GREAT DEAL OF SHEAR IN
THE CLOUD LAYER. THIS WILL MEAN THAT THE BANDS WILL BE TRANSITORY.
SINCE THEY ARE SO NARROW...IT WILL BE DIFFICULT FOR EVEN LIGHT
ACCUMS TO OCCUR. THE INVERSION LOWERS A BIT THIS MORNING AS THE
HIGH OVER THE CENTRAL STATES SLIDES EASTWARD. WILL CONTINUE WITH
THE CURR ADVY IN THE NW 3 COS...CLOSE TO THE LAKE. BUT MOST
PLACES WILL STRUGGLE TO GET EVEN ANOTHER INCH...ESP SINCE THE
SNOW WILL BE BLOWING AROUND AND MAKE MEASURING DIFFICULT. CLOUDS
WILL START TO BREAK UP IN THE MORNING IN THE DOWNSLOPE AREAS...BUT
IT WILL BE TOUGH TO CLEAR UP SKIES OVER THE W.
&&
.SHORT TERM /NOON TODAY THROUGH 6 PM THURSDAY/...
LAKE EFFECT SNOW WANES IN WESTERN ZONES AS INVERSION HEIGHTS COME
DOWN LATER THIS MORNING AND EARLY THIS AFTN. ANY ACCUMS AFTER NOON
WILL BE NEGLIGIBLE. GUSTY WINDS WILL CONTINUE AS PRESSURE RISES
8-10 MB BEFORE SUNSET. TEMPS WILL BE FLAT OR EVEN DROP THROUGH THE
DAY AS THE 8H TEMPS DROP 7-8C THROUGH THE DAY.
THE SFC RIDGE SLIDES OVERHEAD THROUGH THE NIGHT...GRADUALLY
SLACKENING THE WINDS THIS EVENING AND EARLY TONIGHT. MINS WILL BE
IN THE TEENS AND L20S. THESE TEMPS ARE JUST ABOUT AS COLD AS WE
HAVE BEEN THIS WINTER...WITH ONLY THE 10TH-12TH OF THE MONTH AS
COLD OR COLDER. SUNSHINE EARLY IN THE DAY AND RETURN FLOW WILL
ALLOW TEMPS TO RISE BACK TO OR EVEN SLIGHTLY ABOVE NORMALS. AN
APPROACHING NRN STREAM WAVE WILL SPREAD HIGH/MID CLOUDS INTO THE
NRN TIER THROUGH THE DAY ON THURS...BUT ANY LIGHT SNOW SHOULD NOT
ARRIVE UNTIL LATE IN THE DAY IN THE NW.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
A QUICK MOVING CLIPPER SYSTEM WILL SHOOT THROUGH THE GREAT LAKES
AFFECTING MAINLY MY NORTHERN ZONES THURSDAY NIGHT. A SECONDARY
SHOT OF MOISTURE QUICKLY MOVES ALONG THE INTERSTATE 80 CORRIDOR
DURING THE DAY FRIDAY INTO SATURDAY MORNING. THESE FEATURES ARE
SIMILARLY HANDLED BY VARYING MODEL GUIDANCE WITH JUST A FEW
DIFFERENCES IN TIMING AND INTENSITY.
MODELS ALSO AGREE ON ANOTHER SHOT OF MOISTURE MOVING THROUGH LATE
SUNDAY INTO MONDAY AHEAD OF AN ARCTIC AIRMASS TO MOVE IN FOR THE
MIDDLE OF NEXT WEEK. AS WE MOVE INTO THAT TIMEFRAME...SIGNIFICANT
MODEL DIFFERENCES EXIST.
THE ECMWF BRINGS A SLOW MOVING STORM SYSTEM NORTHWEST FROM THE
ATLANTIC COAST WELL INTO PENNSYLVANIA BY THE MIDDLE OF NEXT WEEK.
HOWEVER...THE GFS HAS THE REGION IN COLD NORTHWEST FLOW WITH SOME
OF THE COLDEST AIR OF THE SEASON CLIPPING NORTHEAST PA WITH ONLY
RESULTANT LAKE EFFECT BRINGING SNOW TO THE AREA.
LACK OF SNOW BEGETS LACK OF SNOW. HUGE STORMS IN THE 5-7 DAY RANGE
FIZZLING BEGETS HUGE STORMS IN THE 5-7 DAY RANGE FIZZLING. IT IS
THE TREND OF THIS WINTER SO WILL HOLD OFF ON ANY BELLS...OR
WHISTLES...AT THIS POINT.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
WINDS NOW ARE NW. GUSTY WINDS WILL PREVAIL AS THE COLD AIR ADVECTS
THROUGH THE REGION. EXPECT LAKE ENHANCED SNOW SHOWERS CAUSING IFR
CONDITIONS AT BFD AND JST UNTIL LATE MORNING OR EARLY AFTERNOON.
MVFR CIGS AT UNV AND AOO AT TIMES THIS MORNING...AS THE UPPER LVL
TROUGH MOVES ACROSS. EXPECT VFR CONDITIONS FURTHER EAST.
GENERALLY VFR CONDS EXPECTED ON THU...ALTHOUGH SOME -SHSN ARE
POSSIBLE LATE ACROSS NW PA.
A SLIGHTLY BETTER CHC OF SNOW OR RAIN SHOWERS FRI...AS A CLIPPER
SYSTEM MOVES EASTWARD...JUST NORTH OF PA.
VFR CONDS RETURN FOR NEW YEARS WEEKEND...AS HIGH PRESSURE
BUILDS IN. PERHAPS A SHOWER LATE SUNDAY WITH THE NEXT
COLD FRONT.
OUTLOOK...
THU...GENERALLY VFR.
FRI...MVFR/IFR MAINLY WESTERN AREAS WITH RAIN/SNOW SHOWERS.
SAT-SUN...MAINLY VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR PAZ004-005-
010.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...TYBURSKI
AVIATION...CERU/MARTIN/EVANEGO
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
639 AM EST WED DEC 28 2011
.SYNOPSIS...
BLUSTERY WEST WINDS WILL CREATE SOME LAKE EFFECT SNOW AND
FLURRIES TODAY...BUT THE SNOW SHOWERS WILL TAPER OFF THROUGH THE
DAY. WEAK HIGH PRESSURE TONIGHT WILL BE PUSHED TO THE SOUTH AS A
COUPLE OF ALBERTA CLIPPERS MOVE ACROSS THE GREAT LAKES THURSDAY
NIGHT AND FRIDAY...AND COULD PRODUCE A FEW INCHES OF SNOW IN THE
NORTH AND WEST. FAIR WEATHER SHOULD FOLLOW FOR SATURDAY.
&&
.NEAR TERM /UNTIL NOON TODAY/...
TIGHT P-GRADIENT AROUND THE DEPARTED STORM WILL CONTINUE TO CREATE
GUSTY WINDS OVER THE STATE. BUFKIT MOMENTUM TRANSFER VALUES FROM
NAM AND RUC SHOW GUSTS WILL PROBABLY TOP OUT IN THE M/U30KT
RANGE...BUT RUN THROUGH MUCH OF THE DAY. LAST VESTIGE OF THE UPPER
LOW APPEARS TO HAVE JUST PASSED KELZ AND KUNV. RADAR SHOWS SNOW IN
VERY LONG BUT ALSO VERY THIN/NARROW BANDS. VERY FEW IFR OBS TO BE
FOUND. THE GUSTY WINDS WILL BE CREATING A GREAT DEAL OF SHEAR IN
THE CLOUD LAYER. THIS WILL MEAN THAT THE BANDS WILL BE TRANSITORY.
SINCE THEY ARE SO NARROW...IT WILL BE DIFFICULT FOR EVEN LIGHT
ACCUMS TO OCCUR. THE INVERSION LOWERS A BIT THIS MORNING AS THE
HIGH OVER THE CENTRAL STATES SLIDES EASTWARD. WILL CONTINUE WITH
THE CURR ADVY IN THE NW 3 COS...CLOSE TO THE LAKE. BUT MOST
PLACES WILL STRUGGLE TO GET EVEN ANOTHER INCH...ESP SINCE THE
SNOW WILL BE BLOWING AROUND AND MAKE MEASURING DIFFICULT. CLOUDS
WILL START TO BREAK UP IN THE MORNING IN THE DOWNSLOPE AREAS...BUT
IT WILL BE TOUGH TO CLEAR UP SKIES OVER THE W.
&&
.SHORT TERM /NOON TODAY THROUGH 6 PM THURSDAY/...
LAKE EFFECT SNOW WANES IN WESTERN ZONES AS INVERSION HEIGHTS COME
DOWN LATER THIS MORNING AND EARLY THIS AFTN. ANY ACCUMS AFTER NOON
WILL BE NEGLIGIBLE. GUSTY WINDS WILL CONTINUE AS PRESSURE RISES
8-10 MB BEFORE SUNSET. TEMPS WILL BE FLAT OR EVEN DROP THROUGH THE
DAY AS THE 8H TEMPS DROP 7-8C THROUGH THE DAY.
THE SFC RIDGE SLIDES OVERHEAD THROUGH THE NIGHT...GRADUALLY
SLACKENING THE WINDS THIS EVENING AND EARLY TONIGHT. MINS WILL BE
IN THE TEENS AND L20S. THESE TEMPS ARE JUST ABOUT AS COLD AS WE
HAVE BEEN THIS WINTER...WITH ONLY THE 10TH-12TH OF THE MONTH AS
COLD OR COLDER. SUNSHINE EARLY IN THE DAY AND RETURN FLOW WILL
ALLOW TEMPS TO RISE BACK TO OR EVEN SLIGHTLY ABOVE NORMALS. AN
APPROACHING NRN STREAM WAVE WILL SPREAD HIGH/MID CLOUDS INTO THE
NRN TIER THROUGH THE DAY ON THURS...BUT ANY LIGHT SNOW SHOULD NOT
ARRIVE UNTIL LATE IN THE DAY IN THE NW.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
A QUICK MOVING CLIPPER SYSTEM WILL SHOOT THROUGH THE GREAT LAKES
AFFECTING MAINLY MY NORTHERN ZONES THURSDAY NIGHT. A SECONDARY
SHOT OF MOISTURE QUICKLY MOVES ALONG THE INTERSTATE 80 CORRIDOR
DURING THE DAY FRIDAY INTO SATURDAY MORNING. THESE FEATURES ARE
SIMILARLY HANDLED BY VARYING MODEL GUIDANCE WITH JUST A FEW
DIFFERENCES IN TIMING AND INTENSITY.
MODELS ALSO AGREE ON ANOTHER SHOT OF MOISTURE MOVING THROUGH LATE
SUNDAY INTO MONDAY AHEAD OF AN ARCTIC AIRMASS TO MOVE IN FOR THE
MIDDLE OF NEXT WEEK. AS WE MOVE INTO THAT TIMEFRAME...SIGNIFICANT
MODEL DIFFERENCES EXIST.
THE ECMWF BRINGS A SLOW MOVING STORM SYSTEM NORTHWEST FROM THE
ATLANTIC COAST WELL INTO PENNSYLVANIA BY THE MIDDLE OF NEXT WEEK.
HOWEVER...THE GFS HAS THE REGION IN COLD NORTHWEST FLOW WITH SOME
OF THE COLDEST AIR OF THE SEASON CLIPPING NORTHEAST PA WITH ONLY
RESULTANT LAKE EFFECT BRINGING SNOW TO THE AREA.
LACK OF SNOW BEGETS LACK OF SNOW. HUGE STORMS IN THE 5-7 DAY RANGE
FIZZLING BEGETS HUGE STORMS IN THE 5-7 DAY RANGE FIZZLING. IT IS
THE TREND OF THIS WINTER SO WILL HOLD OFF ON ANY BELLS...OR
WHISTLES...AT THIS POINT.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS THE SYSTEM QUICKLY DEPARTS...WINDS WILL SHIFT FROM THE
WEST TO THE NORTHWEST. GUSTY WINDS WILL PREVAIL AS THE COLD AIR
ADVECTS THROUGH THE REGION. EXPECT LAKE ENHANCED SNOW SHOWERS
CAUSING IFR CONDITIONS AT BFD AND JST UNTIL LATE MORNING OR EARLY
AFTERNOON. MVFR CIGS AT UNV AND AOO AT TIMES THIS MORNING...AS THE
UPPER LVL TROUGH MOVES ACROSS. EXPECT VFR CONDITIONS FURTHER EAST.
GENERALLY VFR CONDS EXPECTED ON THU...ALTHOUGH SOME -SHSN ARE
POSSIBLE LATE ACROSS NW PA.
A SLIGHTLY BETTER CHC OF SNOW OR RAIN SHOWERS FRI...AS A CLIPPER
SYSTEM MOVES EASTWARD...JUST NORTH OF PA.
VFR CONDS RETURN FOR NEW YEARS WEEKEND.
OUTLOOK...
THU...GENERALLY VFR.
FRI...MVFR/IFR MAINLY WESTERN AREAS WITH RAIN/SNOW SHOWERS.
SAT-SUN...MAINLY VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR PAZ004-005-
010.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...TYBURSKI
AVIATION...CERU/MARTIN/EVANEGO
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
928 AM EST WED DEC 28 2011
.DISCUSSION...
REPORTS FROM THE MOUNTAINS INDICATE BETWEEN 1 AND 4 INCHES OF SNOW
HAS FALLEN OVERNIGHT AND THIS MORNING. LIGHT RADAR ECHOS HAVE
DIMINISHED FROM EARLIER THIS MORNING...AND THE 12Z OHX SOUNDING
SHOWS DRIER AIR WILL ADVECT IN THROUGH THE DAY. CLOUDS ACROSS THE
NORTHERN SECTIONS SHOULD BECOME SCATTERED BY MID AFTERNOON
ACCORDING TO THE RUC AND NAM. WILL UPDATE TO REMOVE ALL POPS...AND
WILL ALLOW THE WINTER WEATHER ADVISORY TO EXPIRE AT 10AM. ONLY
MINOR ADJUSTEMENTS WILL BE MADE TO HOURLY TEMPERATURES AND SKY
GRIDS FOR THE UPDATE.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR THE
FOLLOWING ZONES: BLOUNT SMOKY MOUNTAINS...COCKE SMOKY
MOUNTAINS...JOHNSON...SEVIER SMOKY MOUNTAINS...SOUTHEAST
CARTER...SOUTHEAST GREENE...UNICOI.
VA...WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR THE
FOLLOWING ZONES: WISE.
&&
$$
DGS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
425 PM EST WED DEC 28 2011
.SHORT TERM...
TONIGHT THROUGH THURSDAY NIGHT
PAIR OF WEAK CLIPPER SYSTEMS TO IMPACT THE AREA IN THE SHORT TERM.
WATER VAPOR IMAGERY AND LATEST RUC ANALYSIS DEPICTING LEAD SHORT
WAVE OVER SOUTHERN MANITOBA AND MOVING INTO WESTERN ONTARIO. THIS
FEATURE EXPECTED TO WEAKEN/SHEAR OUT IN FAST MOVING NW FLOW PATTERN
AS IT DROPS DOWN INTO THE NORTHERN GREAT LAKES TONIGHT/THU AM.
RESULT SHOULD BE BETTER CHANCES FOR PRECIP TO REMAIN NORTH OF THE
AREA WHERE BETTER FORCING AND MOISTURE WILL BE PRESENT...BUT CLOSE
ENOUGH TO MAINTAIN SMALL CHANCE POPS FOR NORTHERN TWO THIRDS OF CWA.
MODELS INDICATING DECENT SFC/LOW LEVEL RESPONSE WITH THIS FIRST
SHORT WAVE RESULTING IN GOOD WAA IN ADVANCE OF THIS SYSTEM WHICH
WILL HAVE TEMPS SLOWLY RISING AFTER MIDNIGHT TONIGHT AND ALSO BRING
PRECIP TYPE INTO QUESTION. FCST SOUNDINGS SHOWING DECENT ELEVATED
WARM LAYER AND MORE FAVORABLE PROFILES IN SUPPORT OF LIQUID
PRECIP...AND WHILE 12Z SOUNDINGS FROM KOAX AND KSGF LEND CREDENCE TO
THIS SCENARIO...STILL NOT CONVINCED THAT MUCH LOW LEVEL WARMING WILL
BE REALIZED WITH FAST MOVING SYSTEM SO WILL KEEP WITH RA/SN MIX IN
WX GRIDS ATTM. 140KT JET COMING ONSHORE IN PACIFIC NW THIS MORNING
WILL DRIVE SECOND SHORT WAVE INTO THE AREA QUICKLY BEHIND THE FIRST
THURSDAY NIGHT. THIS WAVE WILL DIG FURTHER SOUTH AND BRING BETTER
FORCING AND MOISTURE INTO THE FORECAST AREA...AS CURRENTLY REFLECTED
IN GRIDS WITH LOW TO HIGH CHANCE POPS FROM EAST TO WEST ACROSS THE
CWA. STILL LIKE THE NOTION OF A SMALL WINDOW OF DRY WX BETWEEN THESE
TWO SYSTEMS SO WILL STAY WITH DRY FCST 00-06Z FRI. WITH RELATIVELY
WARMER AIR IN PLACE...WILL TREND WX GRIDS TOWARD LIQUID PRECIP WITH
ALL RAIN IN THE SOUTHERN TIER BUT STAY WITH MIX ELSEWHERE GIVEN
NOCTURNAL TIMING. ABOVE NORMAL TEMPS THROUGH THE PERIOD AND GUIDANCE
REASONABLE IN HANDLING THIS.
&&
.LONG TERM...
FRIDAY THROUGH WEDNESDAY
AN UPPER LEVEL DISTURBANCE WILL TRACK SOUTHEASTWARD FROM SOUTHERN
ALBERTA/SASKATCHEWAN THURSDAY MORNING INTO THE MIDWEST BY FRIDAY
MORNING. MEDIUM RANGE MODELS ARE IN DECENT AGREEMENT WITH THE TRACK
OF THE WAVE AND THE ATTENDANT SURFACE LOW...HOWEVER MINOR TIMING
DIFFERENCES EXIST. WENT AHEAD AND BUMPED POPS UP TO LIKELY ACROSS
THE NORTHERN HALF OF THE CWA FRIDAY MORNING...ALONG THE PREFERRED
TRACK OF THE SURFACE LOW. PRECIPITATION TYPE CONCERNS REMAIN AN
ISSUE WITH THIS SYSTEM. THERMAL PROFILES PER MODELS SOUNDINGS
SUGGEST MOSTLY RAIN WITH THIS SYSTEM THROUGH THE DAY FRIDAY...WITH
COLDER AIR ARRIVING LATE AFTERNOON...INTRODUCING A MIX AND EVENTUAL
CHANGEOVER TO SNOW AND PRECIPITATION TAPERS OFF. HOWEVER...GIVEN THE
TIMING DIFFERENCES BETWEEN MODELS....AND SLIGHT MODEL DIFFERENCES
WITH THE TRACK OF THE SYSTEM...PREFERRED TO LEAVE A RAIN/SNOW
MENTION FOR FRIDAY ACROSS THE NORTH AND FRIDAY NIGHT EVERYWHERE.
WILL DEFER REFINING OF P-TYPE TO NEXT FORECAST CYCLE AND HOPEFULLY
MORE CONSISTENT MODEL SOLUTIONS. NO MAJOR CHANGES TO TEMPERATURES
FRIDAY AND FRIDAY NIGHT.
SYSTEM EXITS THE REGION BY SATURDAY MORNING...AND HIGH PRESSURE
BUILDS INTO THE REGION FROM THE SOUTHWEST. CONDITIONS WILL BE DRY
THROUGH THE DAY SATURDAY...BEFORE A SIGNIFICANT PATTERN CHANGE
ARRIVES ACROSS THE REGION.
UPPER LEVEL TROF WILL DIG SOUTHEAST FROM CANADA INTO THE EASTERN
CONUS SUNDAY INTO EARLY NEXT WEEK...AND ALONG WITH IT A POLAR AIR
MASS...WITH MODEL H85 TEMPS APPROACHING -20C BY TUESDAY ACROSS THE
REGION. SFC LOW PRESSURE WILL MOVE ACROSS THE NORTHERN TIER INTO THE
GREAT LAKES REGION BY BY SUNDAY. MODELS DIFFER WITH THE EXACT TRACK
OF THE LOW...WITH THE GFS SUPPORTING A FASTER MORE SOUTHERLY
TRACK...AND THE ECMWF A BIT SLOWER WITH A MORE NORTHERLY TRACK.
CONSEQUENTLY...THE GFS SUPPORTS STRONGER FORCING ACROSS THE REGION
SATURDAY NIGHT INTO SUNDAY...WHILE THE ECMWF SUPPORTS WEAKER FORCING
MOVING INTO THE AREA DURING THE DAY SUNDAY. ALLBLEND PROCEDURE
INTRODUCED SLIGHT CHANCE POPS ON SATURDAY NIGHT...WHICH HAVE BEEN
RETAINED FOR COLLABORATIVE PURPOSES. FEEL THAT THE GFS IS SLIGHTLY
TO FAST WITH THE TRACK OF THE SYSTEM AND BEST PRECIP CHANCES WILL BE
DURING THE DAY SUNDAY.
COLD AIR WILL THEN FILTER INTO THE REGION BEHIND THE FRONT...WHICH
WILL BE THE CATALYST FOR LAKE EFFECT SNOW LATE SUNDAY THROUGH
TUESDAY ACROSS THE AREA. MODELS ARE IN DECENT AGREEMENT OF A NW TO
NORTHERLY FETCH AND ADEQUATE MOISTURE PROFILE...WITH LAKE SFC TO H85
DELTA TS IN EXCESS OF 20C...AND LAKE SFC TO H7 DELTA TS IN THE MID
TO UPPER 20C RANGE. WENT AHEAD AND RAISED POPS SUNDAY NIGHT INTO
TUESDAY TO HIGH CHANCE ACROSS LAKE EFFECT PREFERRED AREAS. NO MAJOR
CHANGES TO TEMPERATURES...AS THE ALLBLEND SOLUTIONS HAVE CAUGHT ON
TO COLDER TEMPERATURES WITH THE ARRIVAL OF THE POLAR AIR MASS.&&
.AVIATION... / 18Z TAFS /
LATEST OBS INDICATING THAT MVFR LAKE EFFECT CLOUDS STILL IMPACTING
KSBN. DIFFICULT TO DETERMINE TRENDS FROM VIS SAT GIVEN MID LEVEL
DECK ON TOP...BUT WILL EXTEND A TEMPO MVFR FOR FIRST HOUR OF THIS
CYCLE AT KSBN THEN BELIEVE WINDS BACKING TO MORE SW LATER THIS
AFTERNOON SHOULD SHIFT LAKE EFFECT CLOUDS TO THE NORTH AND EAST.
WEAK CLIPPER SYSTEM MOVING DOWN TONIGHT WILL KEEP MVFR DECK IN PLACE
OVER BOTH SITES AND ALSO CONTINUE BACKING OF WINDS TO MORE SOUTHERLY
AND INCREASE TO 10-15KTS TOWARD THE END OF THE PERIOD. UNCERTAINTY
OF PRECIP DEVELOPMENT WITH THIS SYSTEM WILL PRECLUDE ANY MENTION FOR
THIS TAF CYCLE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SHORT TERM...LOGSDON
LONG TERM...NG
AVIATION...LOGSDON
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1019 AM MST WED DEC 28 2011
.SYNOPSIS...
222 AM MST WED DEC 28 2011
LATEST SATELLITE IMAGERY AND RUC ANALYSIS SHOW AN UPPER LEVEL RIDGE
OVER THE WEST COAST...WITH AREAS OF CLOUDS AND PRECIPITATION MOVING
ALONG THE NORTHERN PERIPHERY. OVER THE HIGH PLAINS A SHORT WAVE
TROUGH WAS PROGRESSING SOUTHEAST INTO TEXAS. AT THE SURFACE A
TROUGH WAS MOVING THROUGH THE TRI-STATE AREA WITH SOUTHWEST WINDS
TURNING TO THE NORTHWEST BEHIND THE TROUGH.
JTL
&&
.SHORT TERM (TODAY-FRIDAY)...
222 AM MST WED DEC 28 2011
ABOVE NORMAL TEMPERATURES WILL BE THE FOCUS FOR THIS PERIOD.
TODAY...NORTHWEST FLOW WILL CONTINUE OVER THE AREA WITH A MINOR
SHORT WAVE TROUGH MOVING THROUGH THE FLOW DURING THE DAY. WITH THE
RIGHT EXIT REGION OF THE JET MOVING IN AND SOME MOISTURE MOVING
THROUGH THE FLOW...AM NOT ANTICIPATING ANYTHING MORE THAN SOME
CLOUDS. WINDS WILL BE BREEZY TODAY AS SOME OF THE STRONGER WINDS
ABOVE THE SURFACE ACCOMPANYING THE TROUGH ARE ABLE TO MIX DOWN.
TEMPERATURES WILL BE WARMER THAN YESTERDAY AS 850MB TEMPERATURES
WARM BEHIND THE TROUGH.
THURSDAY AND FRIDAY...A COUPLE OF SHORT WAVE TROUGHS WILL MOVE
THROUGH THE NORTHWEST FLOW...PLACING THE RIGHT ENTRANCE AND LEFT
EXIT REGIONS OF THE JET OVER THE TRI-STATE AREA. SOME 700-300MB
FRONTOGENESIS WILL MOVE OVER THE AREA WITH THESE TROUGHS. MODELS
DISAGREE WITH HOW MUCH MOISTURE IS PRESENT AS THE TROUGHS MOVE
THROUGH...ESPECIALLY FOR THE TROUGH COMING THROUGH FRIDAY MORNING.
SREF PRECIPITATION PROBABILITIES ARE ZERO WHILE THE GEFS DOES SHOW
A SMALL CHANCE FOR SOME MINIMAL PRECIPITATION IN THE
BENKELMAN...MCCOOK AND OBERLIN AREA. WITH SUCH DISAGREEMENT AMONG
MODELS...WILL LEAVE FORECAST DRY FOR NOW.
WINDS WILL STRENGTHEN THURSDAY AS STRONG UPPER LEVEL WINDS
ACCOMPANY THE TROUGH THROUGH THE AREA AND ARE ABLE TO MIX TO THE
SURFACE. CURRENTLY LOOKS LIKE AREAS NORTH OF HIGHWAY 36 WILL HAVE
THE BEST MIXING AND STRONGEST WINDS...WITH GUSTS UP TO 35 MPH
POSSIBLE. THE WINDS WILL DECREASE AT SUNSET. FRIDAY WINDS WILL BE
LIGHT AS A SURFACE HIGH PRESSURE MOVES INTO THE AREA AHEAD OF A
DEVELOPING SURFACE TROUGH OVER COLORADO.
TEMPERATURE-WISE THURSDAY WILL BE THE WARMEST...WITH HIGHS
REACHING THE LOWER 60S THANKS TO 850MB TEMPERATURES WARMING AS THE
TROUGH MOVES THROUGH. FRIDAY TEMPERATURES WILL BE A FEW DEGREES
COOLER AS COOLER AIR BEHIND THE TROUGH FROM FRIDAY MORNING MOVES
INTO THE AREA.
JTL
.LONG TERM (SATURDAY-TUESDAY)...
222 AM MST WED DEC 28 2011
NEW ECMWF IS MORE IN LINE WITH THE GFS SATURDAY BRINGING A
SHORTWAVE TROUGH AND COLD FRONT THROUGH THE FORECAST AREA.
DEPENDING ON THE TIMING OF THE FRONT...TEMPERATURES MAY WARM
NICELY IN THE MORNING. CURRENT PROJECTIONS OF FRONTAL PASSAGE IN
THE AFTERNOON...THOUGH...WILL LIMIT TOO MUCH WARMING...AND WILL
CONTINUE WITH HIGH TEMPERATURES IN THE LOWER TO MID 50S. ECMWF
CONTINUES TO DEPICT LIGHT PRECIPITATION SATURDAY NIGHT OVER THE
NORTHERN SECTION OF AREA...BUT AGREE WITH OTHER MODELS ABOUT THE
LIMITED AMOUNT OF MOISTURE SO WILL CONTINUE WITH A DRY FORECAST.
STRONG 500 MB RIDGE WILL THEN BUILD OVER THE WESTERN UNITED
STATES BEGINNING SUNDAY AND CONTINUING THROUGH THE EARLY PART OF
NEXT WEEK. THE QUESTION WILL BE HOW FAR EAST THE RIDGE AXIS MOVES
AND HOW STRONG THE HEIGHT RISES WILL BE. THE ECMWF IS SLIGHTLY
STRONGER WITH THE RIDGE AXIS...BUT ALSO FURTHER WEST OF THE GFS.
THIS PLACES STRONG NORTH TRAJECTORIES OVER THE AREA MONDAY FOR
SOME COLD AIR ADVECTION. THE GFS IS FURTHER EAST AND WOULD SUPPORT
WARMER TEMPERATURES. REGARDLESS...BOTH MODELS PROG 500 MB HEIGHTS
OVER 576 METERS BY TUESDAY FOR ABOVE NORMAL TEMPERATURES AND
CONTINUED DRY.
&&
.AVIATION...
1019 AM MST WED DEC 28 2011
FOR THE 18Z TAFS...VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD.
WINDS WILL BE WESTERLY...AND SIMILAR TO YESTERDAY...KGLD WILL SEE
AFTERNOON GUSTS NEARING 20 KNOTS. HIGH CLOUDS WILL MOVE OVER THE
TERMINALS THROUGHOUT THE AFTERNOON. ANY REMAINING GUSTS WILL
SUBSIDE NEAR 00Z AS DAYTIME MIXING ENDS.
CJS
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1246 PM EST WED DEC 28 2011
UPDATED AVIATION DISCUSSION FOR 18Z TAFS
.UPDATE...
LES CONTINUES ACROSS MARQUETTE AND ALGER COUNTIES AS THE FLOW
REMAINS NORTHERLY OFF THE LAKE. WITH THE RIDGE AXIS OVERHEAD...THE
FLOW SHOULD SHIFT TO THE SOUTH THIS AFTERNOON CAUSING THE LES TO END
RATHER QUICKLY. SOME LIGHT SNOW/FLURRIES OVER MN ASSOCIATED WITH
LEADING WARM ADVECTION WILL MOVE INTO WESTERN UPPER MI LATER THIS
AFTERNOON BUT SHOULD BE OF LITTLE CONSEQUENCE. NO MAJOR CHANGES TO
THE AFTERNOON FORECAST.
BASED ON THE LATEST MODEL GUIDANCE...DID MAKE SOME SUBSTANTIAL
CHANGES TO THE OVERNIGHT AND THURSDAY FORECAST FOR THE EASTERN PART
OF THE FORECAST AREA. LOW PRESSURE OVER THE WESTERN DAKOTAS WILL
MOVE TO THE WESTERN GREAT LAKES LATER TONIGHT INTO THURSDAY. THIS
WILL PUT UPPER MICHIGAN IN A BROAD AREA OF ISENTROPIC LIFT/WARM
ADVECTION. WITH THE BOUNDARY LAYER FLOW BEING SOUTH-SOUTHEAST LATE
TONIGHT INTO THURSDAY COMBINED WITH 850MB TEMPS INITIALLY AROUND
-11C (RISING TO -5C BY THU AFTN)...LAKE ENHANCED SNOW OFF OF LAKE
MICHIGAN SEEMS MORE AND MORE LIKELY FOR SCHOOLCRAFT AND SOUTHERN
LUCE COUNTIES. IN FACT...THE HIGHER RESOLUTION MODEL OUTPUT SUCH AS
THE 4KM NAM NEST INDICATE UP TO 0.7 INCH OF LIQUID LATER TONIGHT
INTO THURSDAY GENERALLY SOUTH OF M-28 IN SCHOOLCRAFT AND LUCE
COUNTIES. STILL NEED TO TAKE A CLOSER LOOK AT THE 12Z RUNS...BUT
GIVEN THAT THIS IS A GOOD SETUP FOR MODERATE TO HEAVY SNOW TO FALL
OFF OF LAKE MICHIGAN IN SCHOOLCRAFT COUNTY...HAVE OPTED TO RAISE
SNOW AMOUNTS TO A STORM TOTAL OF 3-6 INCHES AND RAISE POPS TO
CATEGORICAL FOR THE SAME AREAS. MAY NEED TO ISSUE SOME HEADLINE TO
ADDRESS THE SNOWFALL FOR THE EASTERN FORECAST AREA...HOWEVER IT IS
STILL UNCLEAR IF A WARNING OR ADVISORY WILL BE NEEDED. THIS DECISION
WILL LIKELY BE MADE LATER THIS AFTERNOON.
OTHERWISE...THE REMAINDER OF THE AREA WILL SEE A GENERAL 1-3 INCH
SNOWFALL WITH 700MB MIXING RATIO OF 2 G/KM OVERNIGHT INTO THU
MORNING.
&&
.SYNOPSIS...
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
NE CANADA INTO ERN GREAT LAKES AND A FLAT RIDGE OVER THE WEST
RESULTING IN NW FLOW FROM THE CANADIAN PRAIRIE THROUGH THE WRN GREAT
LAKES. A SHEARED UPSTREAM SHORTWAVE TROUGH WAS MOVING INTO MANITOBA
WHILE ANOTHER IN THE FAST WRLY FLOW OFF THE NE PACIFIC WAS LOCATED
OVER SRN BC. AT THE SFC...A RIDGE EXTENDED FROM NRN ONTARIO INTO WRN
WI LEAVING NRLY FLOW ACROSS LAKE SUPERIOR. 850 MB TEMPS AROUND -15C
PROVIDED PLENTY OF INSTABILITY FOR LINGERING LES EVEN THROUGH VERY
DRY AIR UPSTREAM AND INVERSION HEIGHTS DOWN TO AROUND 3K-4K FT.
&&
.DISCUSSION...
TODAY...EXPECT THAT THE LES WILL DIMINISH THIS MORNING AND END BY
THIS AFTERNOON AS THE RIDGE MOVES ACROSS UPPER MICHIGAN AND WINDS
BECOME OFFSHORE. ANY ACCUMULATIONS WITH SCT -SHSN INTO THE N CNTRL
CWA THIS MORNING SHOULD AMOUNT TO LESS THAN AN INCH. RETURN SRLY
FLOW WILL ALLOW MAX TEMPS TO REBOUND INTO THE UPPER TEENS AND LOWER
20S.
TONIGHT INTO THU...MODELS SUGGEST THAT THE THE MID TO UPPER LEVEL
FORCING WITH THE COMBINATION OF THE MANITOBA AND BC SHORTWAVES
PASSING TO THE NORTH AND SOUTH OF UPPER MI WILL BE RELATIVELY
MODEST. HOWEVER...AN AREA OF 285K-290K ISENTROPIC LIFT NORTH OF THE
850 MB LOW WILL SUPPORT WIDESPREAD LIGHT SNOW...MAINLY BTWN 06Z-18Z.
WITH 2G-3G/KG AVBL...CONSENSUS QPF VALUES IN THE 0.1 TO 0.2...AND
SNOW WATER RATIO VALUES NEAR 15/1...PREVIOUS FCST OF 1 TO 3 INCHES
LOOKS ON TRACK.
THERE IS GREATER UNCERTAINTY WITH THE POTENTIAL FOR HIGHER LAKE
ENHANCED SNOW AMOUNTS WITH SRLY FLOW OFF OF LAKE MICHIGAN. THE HPC
AND LCLY RUN HIGH RES WRF/ARW AS WELL AS THE CANADIAN REGIONAL GEM
SUGGEST THAT A BAND MAY DEVELOP INTO WRN MACKINAC COUNTY LATE
TONIGHT INTO EARLY THU AIDED BY LEVEL LEVEL CONV NEAR THE NW LOWER
MI SHORE. THE BAND MAY SHIFT FARTHER WEST INTO SRN LUCE AND SRN
SCHOOLCRAFT COUNTIES AS WINDS BACK IN RESPONSE TO THE WEAK SFC LOW
MOVING TOWARD NRN LAKE MICHIGAN. ADDITIONAL SNOWFALL AMOUNTS OF
SEVERAL INCHES COULD PUSH OVERALL AMOUNTS INTO THE ADVY CATEGORY IF
THE BANDS DEVELOP AND PERSIST LONG ENOUGH AT ANY LOCATION.
HOWEVER...CONFIDENCE IS BELOW AVERAGE WITH THESE DETAILS.
THU NIGHT INTO FRI...LEFT OVER LIGHT SNOW OVER THE ERN PORTION OF
THE CWA WILL GRADUALLY SLIDE OFF TO THE EAST AS WEAKER ISENTROPIC
LIFT AND FGEN EXIT THE AREA. THE PATH OF THE NEXT SHORTWAVE REMAINS
FAR ENOUGH SOUTH...PER GFS/ECMWF SO THAT FRI WILL REMAIN MAINLY DRY.
SO...ONLY SLIGHT CHANCE POPS WERE INCLUDED.
SAT THROUGH TUE...A PROGRESSIVE MID LEVEL TROUGH MOVES INTO THE
PLAINS BRINGING WAA SAT. WITH LITTLE MOISTURE AVBL...LITTLE/NO
MEASURABLE PCPN IS EXPECTED. THE GFS HAS TRENDED TOWARD THE
GEM/ECMWF WITH TRANSITION TOWARD A MORE AMPLIFIED/MERIDIONAL PATTERN
BY LATE SUN INTO MON. AN INFLUX OF COLD AIR (850 MB TEMPS DOWN INTO
THE -17C TO -20C RANGE) BEHIND A COLD FRONT LATE SUN WITH DEEP
MOISTURE AVAILABLE SHOULD BRING LES TO LOCATIONS FAVORED BY NW TO N
FLOW TIL RIDING MOVES BACK IN BY TUE.
&&
.AVIATION /FOR THE 18Z TAF ISSUANCE/...
EXPECT ANY REMAINING MVFR CIGS TO DISSIPATE EARLY THIS AFTN AT CMX
AND SAW AS FLOW TURNS SOUTHERLY AND THE LES CLOUDS MOVE OFFSHORE.
THE NEXT SYSTEM OVER THE PLAINS WILL APPROACH THE AREA TONIGHT. SOME
LIGHT SNOW MAY SPREAD INTO IWD THIS AFTERNOON AS A WEAK WARM FRONT
APPROACHES THE AREA. WIDESPREAD IFR CIGS AND VSBYS WILL SPREAD
ACROSS THE AREA OVERNIGHT AS THE LOW MOVES INTO WISCONSIN...WITH
LIFR POSSIBLE THU MORNING UNDER THE HEAVIEST SNOW. CONTINUED
IFR/LIFR ON THU AS THE LOW EXITS TO THE EAST.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
AS HIGH PRESSURE MOVES OVER LAKE SUPERIOR TODAY...WINDS WILL
DECREASE AND BECOME MORE SOUTHERLY THROUGH THE DAY. THE NEXT CHANCE
FOR SIGNIFICANT WINDS WILL COME OVER THE WEEKEND AS A LOW PRESSURE
SYSTEM MOVES NORTH OF LAKE SUPERIOR. THE STRONGEST WINDS WILL COME
ON SUNDAY FROM THE NW...AND MAY REACH GALE FORCE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MRD
SYNOPSIS...JLB
DISCUSSION...JLB
AVIATION...MRD
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1126 AM EST WED DEC 28 2011
.UPDATE...
LES CONTINUES ACROSS MARQUETTE AND ALGER COUNTIES AS THE FLOW
REMAINS NORTHERLY OFF THE LAKE. WITH THE RIDGE AXIS OVERHEAD...THE
FLOW SHOULD SHIFT TO THE SOUTH THIS AFTERNOON CAUSING THE LES TO END
RATHER QUICKLY. SOME LIGHT SNOW/FLURRIES OVER MN ASSOCIATED WITH
LEADING WARM ADVECTION WILL MOVE INTO WESTERN UPPER MI LATER THIS
AFTERNOON BUT SHOULD BE OF LITTLE CONSEQUENCE. NO MAJOR CHANGES TO
THE AFTERNOON FORECAST.
BASED ON THE LATEST MODEL GUIDANCE...DID MAKE SOME SUBSTANTIAL
CHANGES TO THE OVERNIGHT AND THURSDAY FORECAST FOR THE EASTERN PART
OF THE FORECAST AREA. LOW PRESSURE OVER THE WESTERN DAKOTAS WILL
MOVE TO THE WESTERN GREAT LAKES LATER TONIGHT INTO THURSDAY. THIS
WILL PUT UPPER MICHIGAN IN A BROAD AREA OF ISENTROPIC LIFT/WARM
ADVECTION. WITH THE BOUNDARY LAYER FLOW BEING SOUTH-SOUTHEAST LATE
TONIGHT INTO THURSDAY COMBINED WITH 850MB TEMPS INITIALLY AROUND
-11C (RISING TO -5C BY THU AFTN)...LAKE ENHANCED SNOW OFF OF LAKE
MICHIGAN SEEMS MORE AND MORE LIKELY FOR SCHOOLCRAFT AND SOUTHERN
LUCE COUNTIES. IN FACT...THE HIGHER RESOLUTION MODEL OUTPUT SUCH AS
THE 4KM NAM NEST INDICATE UP TO 0.7 INCH OF LIQUID LATER TONIGHT
INTO THURSDAY GENERALLY SOUTH OF M-28 IN SCHOOLCRAFT AND LUCE
COUNTIES. STILL NEED TO TAKE A CLOSER LOOK AT THE 12Z RUNS...BUT
GIVEN THAT THIS IS A GOOD SETUP FOR MODERATE TO HEAVY SNOW TO FALL
OFF OF LAKE MICHIGAN IN SCHOOLCRAFT COUNTY...HAVE OPTED TO RAISE
SNOW AMOUNTS TO A STORM TOTAL OF 3-6 INCHES AND RAISE POPS TO
CATEGORICAL FOR THE SAME AREAS. MAY NEED TO ISSUE SOME HEADLINE TO
ADDRESS THE SNOWFALL FOR THE EASTERN FORECAST AREA...HOWEVER IT IS
STILL UNCLEAR IF A WARNING OR ADVISORY WILL BE NEEDED. THIS DECISION
WILL LIKELY BE MADE LATER THIS AFTERNOON.
OTHERWISE...THE REMAINDER OF THE AREA WILL SEE A GENERAL 1-3 INCH
SNOWFALL WITH 700MB MIXING RATIO OF 2 G/KM OVERNIGHT INTO THU
MORNING.
&&
PREV DISCUSSION...ISSUED AT 623 AM EST WED DEC 28 2011...
.SYNOPSIS...
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
NE CANADA INTO ERN GREAT LAKES AND A FLAT RIDGE OVER THE WEST
RESULTING IN NW FLOW FROM THE CANADIAN PRAIRIE THROUGH THE WRN GREAT
LAKES. A SHEARED UPSTREAM SHORTWAVE TROUGH WAS MOVING INTO MANITOBA
WHILE ANOTHER IN THE FAST WRLY FLOW OFF THE NE PACIFIC WAS LOCATED
OVER SRN BC. AT THE SFC...A RIDGE EXTENDED FROM NRN ONTARIO INTO WRN
WI LEAVING NRLY FLOW ACROSS LAKE SUPERIOR. 850 MB TEMPS AROUND -15C
PROVIDED PLENTY OF INSTABILITY FOR LINGERING LES EVEN THROUGH VERY
DRY AIR UPSTREAM AND INVERSION HEIGHTS DOWN TO AROUND 3K-4K FT.
&&
.DISCUSSION...
TODAY...EXPECT THAT THE LES WILL DIMINISH THIS MORNING AND END BY
THIS AFTERNOON AS THE RIDGE MOVES ACROSS UPPER MICHIGAN AND WINDS
BECOME OFFSHORE. ANY ACCUMULATIONS WITH SCT -SHSN INTO THE N CNTRL
CWA THIS MORNING SHOULD AMOUNT TO LESS THAN AN INCH. RETURN SRLY
FLOW WILL ALLOW MAX TEMPS TO REBOUND INTO THE UPPER TEENS AND LOWER
20S.
TONIGHT INTO THU...MODELS SUGGEST THAT THE THE MID TO UPPER LEVEL
FORCING WITH THE COMBINATION OF THE MANITOBA AND BC SHORTWAVES
PASSING TO THE NORTH AND SOUTH OF UPPER MI WILL BE RELATIVELY
MODEST. HOWEVER...AN AREA OF 285K-290K ISENTROPIC LIFT NORTH OF THE
850 MB LOW WILL SUPPORT WIDESPREAD LIGHT SNOW...MAINLY BTWN 06Z-18Z.
WITH 2G-3G/KG AVBL...CONSENSUS QPF VALUES IN THE 0.1 TO 0.2...AND
SNOW WATER RATIO VALUES NEAR 15/1...PREVIOUS FCST OF 1 TO 3 INCHES
LOOKS ON TRACK.
THERE IS GREATER UNCERTAINTY WITH THE POTENTIAL FOR HIGHER LAKE
ENHANCED SNOW AMOUNTS WITH SRLY FLOW OFF OF LAKE MICHIGAN. THE HPC
AND LCLY RUN HIGH RES WRF/ARW AS WELL AS THE CANADIAN REGIONAL GEM
SUGGEST THAT A BAND MAY DEVELOP INTO WRN MACKINAC COUNTY LATE
TONIGHT INTO EARLY THU AIDED BY LEVEL LEVEL CONV NEAR THE NW LOWER
MI SHORE. THE BAND MAY SHIFT FARTHER WEST INTO SRN LUCE AND SRN
SCHOOLCRAFT COUNTIES AS WINDS BACK IN RESPONSE TO THE WEAK SFC LOW
MOVING TOWARD NRN LAKE MICHIGAN. ADDITIONAL SNOWFALL AMOUNTS OF
SEVERAL INCHES COULD PUSH OVERALL AMOUNTS INTO THE ADVY CATEGORY IF
THE BANDS DEVELOP AND PERSIST LONG ENOUGH AT ANY LOCATION.
HOWEVER...CONFIDENCE IS BELOW AVERAGE WITH THESE DETAILS.
THU NIGHT INTO FRI...LEFT OVER LIGHT SNOW OVER THE ERN PORTION OF
THE CWA WILL GRADUALLY SLIDE OFF TO THE EAST AS WEAKER ISENTROPIC
LIFT AND FGEN EXIT THE AREA. THE PATH OF THE NEXT SHORTWAVE REMAINS
FAR ENOUGH SOUTH...PER GFS/ECMWF SO THAT FRI WILL REMAIN MAINLY DRY.
SO...ONLY SLIGHT CHANCE POPS WERE INCLUDED.
SAT THROUGH TUE...A PROGRESSIVE MID LEVEL TROUGH MOVES INTO THE
PLAINS BRINGING WAA SAT. WITH LITTLE MOISTURE AVBL...LITTLE/NO
MEASURABLE PCPN IS EXPECTED. THE GFS HAS TRENDED TOWARD THE
GEM/ECMWF WITH TRANSITION TOWARD A MORE AMPLIFIED/MERIDIONAL PATTERN
BY LATE SUN INTO MON. AN INFLUX OF COLD AIR (850 MB TEMPS DOWN INTO
THE -17C TO -20C RANGE) BEHIND A COLD FRONT LATE SUN WITH DEEP
MOISTURE AVAILABLE SHOULD BRING LES TO LOCATIONS FAVORED BY NW TO N
FLOW TIL RIDING MOVES BACK IN BY TUE.
&&
.AVIATION /FOR THE 12Z TAF ISSUANCE/...
EXPECT LINGERING LES TO WANE THIS MORNING AS THE FLOW BECOMES MORE
ANTICYCLONIC AND VERY DRY AIR UPSTREAM OF LAKE SUPERIOR HAS AN
IMPACT. BUT WITH LINGERING LOW INVERSION BASE AND VERY CHILLY
AIRMASS PASSING OVER LAKE SUPERIOR...EXPECT MVFR CIGS TO LINGER INTO
THIS MORNING. AFTER THE LOW CLOUDS BREAK UP...VFR CONDITIONS WILL
THEN PREVAIL THROUGH MUCH OF THE DAY. ANOTHER BAND OF THICKER
CLOUDS/-SN WILL ARRIVE TOWARD EVENING WITH LOW END VFR/HIGH END MVFR
CONDITIONS. THE BEST CHANCE FOR THE MVFR CIGS WILL BE AT THE FARTHER
N CMX LOCATION.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
AS HIGH PRESSURE MOVES OVER LAKE SUPERIOR TODAY...WINDS WILL
DECREASE AND BECOME MORE SOUTHERLY THROUGH THE DAY. THE NEXT CHANCE
FOR SIGNIFICANT WINDS WILL COME OVER THE WEEKEND AS A LOW PRESSURE
SYSTEM MOVES NORTH OF LAKE SUPERIOR. THE STRONGEST WINDS WILL COME
ON SUNDAY FROM THE NW...AND MAY REACH GALE FORCE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MRD
SYNOPSIS...JLB
DISCUSSION...JLB
AVIATION...TITUS
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
352 PM CST WED DEC 28 2011
.DISCUSSION...
SUMMARY...PATTERN IS A BIT MORE ACTIVE OVER THE NEXT SEVERAL DAYS
IN TERMS OF CHANCES OF PRECIPITATION THAN IT HAS BEEN IN QUITE
SOME TIME. OVERALL...THE OUTLOOK REMAINS WARM SO THE PRECIP EVENTS
EXPECTED TONIGHT...THURSDAY NIGHT AND SATURDAY NIGHT WILL LIKELY
HAVE SOME LIQUID PRECIPITATION ASSOCIATED WITH EACH OF THEM. NO
MAJOR SYSTEMS EXPECTED AND MAXIMUM QPF WITH EACH EVENT SHOULD
LARGELY BE BELOW A QUARTER INCH...A COUPLE OUTLIER RUNS OF THE
NAM/GEM WOULD SUGGEST HIGHER QPF TOTALS WITH THE THURSDAY NIGHT
AND SATURDAY NIGHT SYSTEMS.
THE INTERIOR OF CANADA HAS COOLED SINCE THE LAST TIME I WAS ON A
FORECAST SHIFT LATE LAST WEEK...BUT STILL NO TRUE ARCTIC AIR
ENCROACHING ON THE US CONUS. THE ARCTIC AIR IS STILL BEING
CONFINED TO THE HIGHER LATITUDES...LARGELY ABOVE 55-60 DEGREES
NORTH. PACIFIC AIR MASSES WILL CONTINUE TO IMPACT THE US THROUGH
THE END OF THE YEAR. PROGRESSIVE UPPER FLOW WILL BE FEATURED AS A
SERIES OF DISTURBANCES SURGE FROM THE NORTHEASTERN PACIFIC AND
INTO THE PACIFIC NORTHWEST. THE SOUTHWARD EXTENT OF THIS UPPER
TROUGH SHOULD BE LIMITED BY A RIDGE ACROSS THE SOUTHWEST US. AS A
RESULT...THE SWATH OF PRECIPITATION SHOULD NOT EXTEND MUCH FARTHER
SOUTH THAN 40 DEGREES NORTH. THIS WILL KEEP MN AND WI UNDER THE
GUN FOR A FEW LIGHT PRECIPITATION EVENTS OVER THE COMING DAYS.
THE FAST MOVING FLOW ALOFT WILL KEEP UNSETTLED CONDITIONS IN PLACE
FOR MUCH OF THE PACIFIC NORTHWEST...NORTHERN ROCKIES AND UPPER
MISSISSIPPI VALLEY THROUGH THE WEEKEND. THE FIRST IN A PAIR OF
SYSTEMS IS CURRENTLY MOVING OUT OF THE NORTHERN ROCKIES AND INTO
THE NORTHERN PLAINS. LIGHT RAIN IS RAPIDLY PUSHING INTO THE
EASTERN DAKOTAS LATE THIS AFTERNOON AND THE HRRR TREND IS TAKE THE
LIGHT RAIN INTO WESTERN MN BETWEEN 00-03Z. IF THE CURRENT TRENDS
HOLD...MOST OF THE PRECIP WILL PUSH OUT OF THE FORECAST AREA
BETWEEN 06-09Z...A BIT FASTER THAN THE CURRENT FORECAST INDICATES.
ALSO SOME QUESTION WHETHER OR NOT THE MIXED PRECIPITATION WILL
REALLY PAN OUT IN PARTS OF CENTRAL/SOUTHERN MN. COOLING WILL BE
TOUGH WITH CLOUD COVER AND WEAK WARM AIR ADVECTION. IT MIGHT END
UP BEING NEARLY ALL LIGHT RAIN RATHER THAN SNOW OR FREEZING RAIN.
IN THE EXTENDED...INCREASINGLY MERIDIONAL FLOW WILL LEAD TO MORE
AMPLIFIED TROUGHS ACROSS THE EASTERN PACIFIC THROUGH THE GREAT
LAKES WITH RIDGING SANDWICHED IN BETWEEN. MOST OF THE GUIDANCE
AGREES ON THIS PATTERN...OUTSIDE THE 00Z GFS WHICH WAS BROAD AND
FLAT WITH THE EASTERN TROUGH DESPITE ITS AMPLIFIED RIDGE UPSTREAM.
&&
.AVIATION.../18Z TAF ISSUANCE/
FIRST SHOT OF WAA SNOW SHOWERS/FLURRIES MOVING THROUGH EASTERN AREAS
AT THIS TIME. SHOULD EXIT THE AREA THROUGH 19Z. MAIN CONCERN IS
PRECIPITATION DEVELOPMENT OVER THE NORTHERN AND EASTERN AREAS OF THE
AREA OVERNIGHT. NEXT WAVE MOVING THROUGH NORTHEASTERN MONTANA THIS
AFTERNOON AND SHOULD SPREAD MORE MID/HIGH LEVEL CLOUDS INTO THE WEST
THROUGH 00Z. FORCING IS STRONG BUT DEEP LAYER MOISTURE IS RATHER
LIMITED. SHOULD STILL SEE SOME LIGHT QPF ALONG AND NORTH OF THE SFC
LOW TRACK. THIS WOULD AFFECT ALL TAFS WITH THE EXCEPTION OF KRWF
OVERNIGHT. PRECIPITATION TYPE ALSO A PROBLEM...AS WARM SURGE MOVES
IN WITH THE SURFACE LOW. -FZRA POSSIBLE...AT LEAST BRIEFLY...ALONG
AND NORTH OF THE LOW TRACK. SREF FREEZING RAIN PROBS INCREASE TO
30% INTO WEST CENTRAL WI LATER TONIGHT. CEILINGS ARE EXPECTED TO
DROP TO MVFR AS PRECIPITATION DEVELOPS AND COLD FRONT DROPPING IN
BEHIND...SHOULD CONTINUE LOW END MVFR CONDITIONS OVER MUCH OF THE
AREA INTO THURSDAY MORNING. SOUTHERLY SURFACE WINDS BECOMING
NORTHWEST AS LOW EXITS REGION. SHOULD REMAIN AROUND 10 KNOTS OR
LESS MOST LOCATIONS.
KMSP...MID LEVEL CLOUDS EXITING THE REGION WITH MORE MID/HIGH LEVEL
CLOUDS MOVING IN LATE AFTERNOON FROM THE WEST. STILL LOOKING AT
POSSIBILITY OF LIGHT QPF ASSOCIATED WITH THE WAVE MOVING IN LATER
TONIGHT. BEST SHOT AT PCPN STILL LOOKS LIKE 05Z-08Z. TYPE COULD BE
-RASN AND DEPENDING ON SURFACE TEMP...-FZRA A POSSIBILITY. LOW
CONFIDENCE OF THIS HAPPENING AT THE AIRPORT AT THIS TIME...MORE
LIKELY NORTH OF THE AREA. MVFR CONDS WILL DEVELOP WITH
PRECIPITATION AND LINGER THROUGH THE MORNING AS COLD AIR ADVECTION
DEVELOPS BEHIND SURFACE LOW AND COLD FRONT. SOUTHERLY SURFACE WINDS
BECOMING MORE NORTHWEST BY THURSDAY MORNING WITH PASSAGE OF SURFACE
LOW AND COLD FRONT.
NEXT WAVE MOVING IN OVER WESTERN MN LATE THURSDAY AFTERNOON AND
AFFECTING THE AREA MAINLY AFTER 03Z FRI.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
CLF/DWE
AREA FORECAST DISCUSSION
NWS DULUTH MN
1218 PM CST WED DEC 28 2011
.AVIATION.../18Z TAF ISSUANCE/
AN AREA OF LOW CLOUDS AND VERY LIGHT SNOW WILL CONTINUE TO MOVE
OFF TO THE EAST THIS AFTERNOON. HOWEVER ANOTHER AREA OF CLOUD
COVER WILL REPLACE IT OVERNIGHT TONIGHT AS ANOTHER SYSTEM FROM
CANADA TRACKS EWSEWD ACROSS THE CWA. LIGHT SNOW WILL DEVELOP
ACROSS OUR WRN ZONES THIS EVENING...THEN SPREAD EWD OVERNIGHT TO
AFFECT THE TWIN PORTS...IRON RANGE AND NWRN WI. VSBYS WITHIN THE
SNOWFALL WILL BE IN THE IFR/MVFR RANGE WHILE CIGS SHOULD BE IN THE
MVFR RANGE. THE SNOW WILL QUICKLY TAPER OFF TO SCATTERED LIGHT
SNOW SHOWERS THURSDAY MORNING BEFORE ENDING THURSDAY AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 1211 PM CST WED DEC 28 2011/
UPDATE...
SNOW AREA SPREADING EAST AS FORECAST AND HAVE UPDATED THE FORECAST
TO TAKE OUT THE SNOW FROM THE AREA WEST OF A LINE FROM INL THROUGH
DLH. SATELLITE SHOWS CLEAR SKIES BEHIND THE SNOW...BUT AREA OF LOW
CLOUDS WILL SPREAD SOUTH INTO NORTHERN MN....WHILE WAA CLOUDS WILL
MOVE IN THR THE WEST LATE THIS AFTERNOON.
PREV DISCUSSION... /ISSUED 356 AM CST WED DEC 28 2011/
SHORT TERM...THE MAIN FORECAST CONCERN IN THE SHORT TERM IS THE
AMOUNT AND LOCATION OF ACCUMULATING SNOWFALL TODAY THROUGH TONIGHT.
AT 330 AM...CLOUDS WERE INCREASING AHEAD OF A WEAK SHORTWAVE AND
UP[PER LEVEL JET MAX TRAVERSING ACROSS MN. STRONG LOW LEVEL WAA
AND THETA-E ADVECTION WAS HELPING TO GENERATE LIGHT SNOW ACROSS
WESTERN MN DESPITE INITIALLY DRY LOW LEVEL AIR. THE HRRR RAPID
REFRESH WAS DEPICTING THE AREA OF CLOUDS/LIGHT SNOW FAIRLY WELL.
THE SHORTWAVE AND 100+ KNOT UPPER LEVEL JET MAX WILL CONTINUE TO
PUSH ACROSS THE NORTHLAND TODAY...PUSHING INTO THE WESTERN GREAT
LAKES BY THIS AFTERNOON. THE LATEST HRRR ACTUALLY SHOWS THE
RETURNS DIMINISHING FOR A TIME THIS EARLY MORNING...BEFORE
INCREASING A BIT AGAIN AS THEY REACH NE MN LATER IN THE MORNING.
THINK THERE IS A CHANCE FOR ABOUT A HALF INCH OF SNOWFALL IN SPOTS
TODAY. COULD SEE A BIT MORE ALONG THE SAWTOOTH MOUNTAINS OF THE
NORTH SHORE...AS WINDS COME AROUND TO THE EAST AND SUPPORT LAKE
EFFECT SNOW SHOWERS.
A STRONGER SYSTEM WILL MOVE IN TONIGHT...AND QUICKLY EXIT THE
REGION ON THURSDAY. HAVE SHIFTED THE FOCUS FOR ACCUMULATING
SNOWFALL A BIT TO THE SOUTH BASED ON THE LATEST 00Z MODEL RUNS.
CURRENT THINKING IS THAT THERE WILL BE A STRIPE OF 1 TO 3 INCHES
FROM THE NORTHERN BRAINERD LAKES REGION...THROUGH THE TWIN PORTS
AND INTO NW WI. ALSO CANNOT RULE OUT A NARROW STRIPE OF 2 TO 4
INCHES OR POSSIBLY A BIT MORE AS THE SYSTEM DROPS TO THE SOUTHEAST
AND LAYS DOWN A SWATH OF ACCUMULATING SNOWFALL. THE NORTH SHORE
SHOULD ALSO SEE HIGHER AMOUNTS DUE TO LAKE EFFECT/LAKE
ENHANCEMENT. IN TERMS OF SURFACE LOW PRESSURE...THE MODELS ARE
FAIRLY SIMILAR...BUT QPF AMOUNTS AND LOCATION DO VARY BETWEEN THE
ECMWF/NAM/GFS AND GEM. WILL TAKE A CONSENSUS SOLUTION. MAY NEED TO
BUMP UP AMOUNTS IN LATER FORECAST PACKAGES. IN THE
GRIDS...CURRENTLY HAVE AMOUNTS SIMILAR TO WHAT IS MENTIONED ABOVE.
THINK THE SYSTEM WILL BE FAIRLY EFFICIENT AT RINGING OUT AVAILABLE
MOISTURE.
THE LOW PRESSURE SYSTEM WILL MOVE OUT OF THE REGION ON
THURSDAY...WITH A BIT OF A BREAK BEFORE THE NEXT SYSTEM ARRIVES
THURSDAY NIGHT. THE NAM SOLUTION WOULD SUPPORT HIGHER POPS FOR
THURSDAY NIGHT...BUT THE ECMWF/GFS KEEP THE ACCUMULATING SNOW
GENERALLY WEST AND SOUTH OF THE CWA.
LONG TERM...FRIDAY THROUGH TUESDAY.
FRIDAY...THE LONG TERM PERIOD BEGINS WITH LOW CHANCES OF
SNOWFALL...MAINLY DUE TO THE GFS SHOWING A TROUGH MOVING THROUGH
THE NORTHLAND. IT LOOKS LIKE A RIDGE WILL MOVE INTO THE REGION
FRIDAY NIGHT WITH SOUTHERLY WINDS DEVELOPING BY SATURDAY MORNING.
SATURDAY...IT LOOKS LIKE A RELATIVELY WARM DAY. SOUTHWESTERLY WINDS
WILL DEVELOP AS A LOW PRESSURE SYSTEM MOVES FROM CENTRAL MANITOBA TO
WESTERN ONTARIO. THERE MAY BE SOME LIGHT PCPN ACROSS THE NORTHLAND.
CONSIDERING THE WARMER SURFACE TEMPERATURES AND TEMPERATURES
ALOFT...FORECASTED A POSSIBLE MIXTURE OF RAIN AND SNOW. PLUS...MODEL
SOUNDINGS GENERALLY HAD SATURATION ALOFT TO ONLY ABOUT -5 DEGREES
CELSIUS OR LESS UNTIL LATER IN THE EVENING WHEN THE COLDER AIR IS
USHERED INTO THE NORTHLAND. SO WOULD THINK THE PCPN WOULD LIKELY
TURN BACK TO SNOW SATURDAY NIGHT.
SUNDAY AND MONDAY...THE BEGINNING OF NEXT WEEK SHOULD START OFF
COLD. IT LOOKS LIKE THE POSSIBILITY OF LINGERING SYNOPTIC SNOW
ACROSS THE NORTHLAND...AS WELL AS LAKE EFFECT SNOWFALL ALONG PARTS
OF THE SOUTH SHORE. THE MODELS INDICATE VERY COLD 850 HPA WILL WRAP
INTO THE NORTHLAND...AS LOW AS -16 DEGREES CELSIUS. THIS SHOULD MAKE
FOR A SOLID TEMPERATURE DIFFERENCE BETWEEN 850 HPA AND THE LAKE
SURFACE TEMPERATURE...WHICH IS AROUND 4 DEGREES CELSIUS.
&&
.POINT TEMPS/POPS...
DLH 27 19 29 21 / 30 70 20 20
INL 26 12 26 15 / 30 30 10 20
BRD 32 25 33 24 / 10 60 20 30
HYR 28 20 32 23 / 30 70 30 30
ASX 29 20 33 24 / 20 70 30 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
AVIATION...BERDES
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1211 PM CST WED DEC 28 2011
.UPDATE...
SNOW AREA SPREADING EAST AS FORECAST AND HAVE UPDATED THE FORECAST
TO TAKE OUT THE SNOW FROM THE AREA WEST OF A LINE FROM INL THROUGH
DLH. SATELLITE SHOWS CLEAR SKIES BEHIND THE SNOW...BUT AREA OF LOW
CLOUDS WILL SPREAD SOUTH INTO NORTHERN MN....WHILE WAA SLOUDS WILL
MOVE IN THR THE WEST LATE THIS AFTERNOON.
&&
PREV DISCUSSION... /ISSUED 356 AM CST WED DEC 28 2011/
SHORT TERM...THE MAIN FORECAST CONCERN IN THE SHORT TERM IS THE
AMOUNT AND LOCATION OF ACCUMULATING SNOWFALL TODAY THROUGH TONIGHT.
AT 330 AM...CLOUDS WERE INCREASING AHEAD OF A WEAK SHORTWAVE AND
UP[PER LEVEL JET MAX TRAVERSING ACROSS MN. STRONG LOW LEVEL WAA
AND THETA-E ADVECTION WAS HELPING TO GENERATE LIGHT SNOW ACROSS
WESTERN MN DESPITE INITIALLY DRY LOW LEVEL AIR. THE HRRR RAPID
REFRESH WAS DEPICTING THE AREA OF CLOUDS/LIGHT SNOW FAIRLY WELL.
THE SHORTWAVE AND 100+ KNOT UPPER LEVEL JET MAX WILL CONTINUE TO
PUSH ACROSS THE NORTHLAND TODAY...PUSHING INTO THE WESTERN GREAT
LAKES BY THIS AFTERNOON. THE LATEST HRRR ACTUALLY SHOWS THE
RETURNS DIMINISHING FOR A TIME THIS EARLY MORNING...BEFORE
INCREASING A BIT AGAIN AS THEY REACH NE MN LATER IN THE MORNING.
THINK THERE IS A CHANCE FOR ABOUT A HALF INCH OF SNOWFALL IN SPOTS
TODAY. COULD SEE A BIT MORE ALONG THE SAWTOOTH MOUNTAINS OF THE
NORTH SHORE...AS WINDS COME AROUND TO THE EAST AND SUPPORT LAKE
EFFECT SNOW SHOWERS.
A STRONGER SYSTEM WILL MOVE IN TONIGHT...AND QUICKLY EXIT THE
REGION ON THURSDAY. HAVE SHIFTED THE FOCUS FOR ACCUMULATING
SNOWFALL A BIT TO THE SOUTH BASED ON THE LATEST 00Z MODEL RUNS.
CURRENT THINKING IS THAT THERE WILL BE A STRIPE OF 1 TO 3 INCHES
FROM THE NORTHERN BRAINERD LAKES REGION...THROUGH THE TWIN PORTS
AND INTO NW WI. ALSO CANNOT RULE OUT A NARROW STRIPE OF 2 TO 4
INCHES OR POSSIBLY A BIT MORE AS THE SYSTEM DROPS TO THE SOUTHEAST
AND LAYS DOWN A SWATH OF ACCUMULATING SNOWFALL. THE NORTH SHORE
SHOULD ALSO SEE HIGHER AMOUNTS DUE TO LAKE EFFECT/LAKE
ENHANCEMENT. IN TERMS OF SURFACE LOW PRESSURE...THE MODELS ARE
FAIRLY SIMILAR...BUT QPF AMOUNTS AND LOCATION DO VARY BETWEEN THE
ECMWF/NAM/GFS AND GEM. WILL TAKE A CONSENSUS SOLUTION. MAY NEED TO
BUMP UP AMOUNTS IN LATER FORECAST PACKAGES. IN THE
GRIDS...CURRENTLY HAVE AMOUNTS SIMILAR TO WHAT IS MENTIONED ABOVE.
THINK THE SYSTEM WILL BE FAIRLY EFFICIENT AT RINGING OUT AVAILABLE
MOISTURE.
THE LOW PRESSURE SYSTEM WILL MOVE OUT OF THE REGION ON
THURSDAY...WITH A BIT OF A BREAK BEFORE THE NEXT SYSTEM ARRIVES
THURSDAY NIGHT. THE NAM SOLUTION WOULD SUPPORT HIGHER POPS FOR
THURSDAY NIGHT...BUT THE ECMWF/GFS KEEP THE ACCUMULATING SNOW
GENERALLY WEST AND SOUTH OF THE CWA.
LONG TERM...FRIDAY THROUGH TUESDAY.
FRIDAY...THE LONG TERM PERIOD BEGINS WITH LOW CHANCES OF
SNOWFALL...MAINLY DUE TO THE GFS SHOWING A TROUGH MOVING THROUGH
THE NORTHLAND. IT LOOKS LIKE A RIDGE WILL MOVE INTO THE REGION
FRIDAY NIGHT WITH SOUTHERLY WINDS DEVELOPING BY SATURDAY MORNING.
SATURDAY...IT LOOKS LIKE A RELATIVELY WARM DAY. SOUTHWESTERLY WINDS
WILL DEVELOP AS A LOW PRESSURE SYSTEM MOVES FROM CENTRAL MANITOBA TO
WESTERN ONTARIO. THERE MAY BE SOME LIGHT PCPN ACROSS THE NORTHLAND.
CONSIDERING THE WARMER SURFACE TEMPERATURES AND TEMPERATURES
ALOFT...FORECASTED A POSSIBLE MIXTURE OF RAIN AND SNOW. PLUS...MODEL
SOUNDINGS GENERALLY HAD SATURATION ALOFT TO ONLY ABOUT -5 DEGREES
CELSIUS OR LESS UNTIL LATER IN THE EVENING WHEN THE COLDER AIR IS
USHERED INTO THE NORTHLAND. SO WOULD THINK THE PCPN WOULD LIKELY
TURN BACK TO SNOW SATURDAY NIGHT.
SUNDAY AND MONDAY...THE BEGINNING OF NEXT WEEK SHOULD START OFF
COLD. IT LOOKS LIKE THE POSSIBILITY OF LINGERING SYNOPTIC SNOW
ACROSS THE NORTHLAND...AS WELL AS LAKE EFFECT SNOWFALL ALONG PARTS
OF THE SOUTH SHORE. THE MODELS INDICATE VERY COLD 850 HPA WILL WRAP
INTO THE NORTHLAND...AS LOW AS -16 DEGREES CELSIUS. THIS SHOULD MAKE
FOR A SOLID TEMPERATURE DIFFERENCE BETWEEN 850 HPA AND THE LAKE
SURFACE TEMPERATURE...WHICH IS AROUND 4 DEGREES CELSIUS.
&&
.POINT TEMPS/POPS...
DLH 27 19 29 21 / 30 70 20 20
INL 26 12 26 15 / 30 30 10 20
BRD 32 25 33 24 / 10 60 20 30
HYR 28 20 32 23 / 30 70 30 30
ASX 29 20 33 24 / 20 70 30 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...CLC
LONG TERM....BERDES
AREA FORECAST DISCUSSION
NWS BILLINGS MT
950 AM MST WED DEC 28 2011
.SHORT TERM...VALID FOR TDY AND THU...
UPDATE TO MORNING FORECAST TO ISSUE HIGH WIND WARNING ACROSS
WESTERN COUNTIES...INCLUDING MUSSELSHELL...YELLOWSTONE...AND EAST
CARBON COUNTIES...AND AREAS WEST. WINDS ARE EXPECTED TO PICK UP
THIS AFTERNOON ACROSS THE WESTERN ZONES...WITH SUSTAINED WINDS
REACHING AROUND 40 MPH AND GUSTS APPROACHING 60 MPH. ALTHOUGH GFS
INDICATES AN INVERSION REMAINING IN PLACE ACROSS THE AREA...NAM
AND RUC MODELS BOTH INDICATE BREAK DOWN OF INVERSION THIS
AFTERNOON...WITH STEEP LAPSE RATES IN THE 1000-850MB
LEVEL...RANGING FROM 6 TO 9 C/KM. THIS SHOULD ALLOW FOR STRONG
WINDS ALOFT TO MIX DOWN TO THE SFC. WINDS ARE EXPECTED TO DROP OFF
THIS EVENING AFTER SUNSET...AS THE INVERSION REDEVELOPS. WINDS
WILL PICK UP AGAIN TOMORROW BY LATE MORNING/EARLY AFTERNOON...AND
ARE EXPECTED TO BE EVEN STRONGER THAN WINDS EXPERIENCED TODAY.
OTHERWISE OVERALL FORECAST APPEARS IN GOOD SHAPE. AAG
...PREVIOUS DISCUSSION...
VERY DYNAMIC PATTERN OVER OUR FORECAST AREA THE NEXT COUPLE OF
DAYS. MODELS GENERALLY IN GOOD AGREEMENT. MAIN FORECAST ISSUE
WILL BE WIND HIGHLIGHTS ACROSS THE PLAINS.
EARLY THIS MORNING RADAR TRENDS ALREADY INDICATED SOME LIGHT
PRECIP ACROSS THE NORTHERN AND CENTRAL ZONES EXTENDING FROM
SUMATRA SOUTH INTO BIG HORN COUNTY. SNOW WAS ALSO INDICATED IN
THE HIGH COUNTRY WHERE WEB CAMS SHOWED SNOW AT COOKE CITY. THIS
PRECIPITATION CAN BE ATTRIBUTED TO WARM AIR ADVECTION AT 700
MB...AND FAVORABLE JET DYNAMICS WHERE OUR REGION IS UNDER THE
INFLUENCE OF LEFT EXIT REGION. THIS IS BATTLING THE STRONG
DOWNSLOPE FLOW OFF THE HIGHER TERRAIN WHICH IS WHY LITTLE RADAR
RETURNS ARE OCCURRING IN THE FOOTHILLS. THE JET MAX ASSOCIATED
WITH THIS FORCING WILL SHIFT QUICKLY EAST BY MIDDAY BRINGING AN
END TO MUCH OF THE PRECIP...THOUGH SOME WARM AIR ADVECTION WILL
CONTINUE.
FAVORABLE PRESSURE GRADIENT WILL CONTINUE FOR THE LIVINGSTON AND
NYE AREAS TODAY. THUS WARNING FOR THESE AREAS LOOKS GOOD AS HYBRID
GAP FLOW AND MIX DOWN MAY RESULT IN GUSTS TO 75-80 MPH. THE
GRADIENT IS SOMEWHAT WEAKER TONIGHT AND NEW DATA SUGGEST QUITE A
BIT WEAKER THURSDAY.THEREFORE...WARNING FOR THESE AREAS THROUGH
TODAY LOOKS GOOD...BUT MAY NEED TO BE DROPPED EARLY IF MODEL
TRENDS CONTINUE TO INDICATE A WEAKENING GRADIENT TONIGHT AND
THURSDAY. WILL LET THE DAY SHIFT TAKE ANOTHER LOOK AT THIS.
AS FOR HIGH WINDS ON THE PLAINS...THE WARM AIR COMING IN AT THE
700MB LEVEL WILL TEND TO LIMIT POTENTIAL MIX DOWN OF STRONG WINDS
TODAY TO AT LEAST SOME EXTENT. HOWEVER...WITH 40 TO 50 KNOT WINDS
ONLY 1200-1500 FEET OFF THE GROUND WILL CONTINUE TO RIDE THE HIGH
WIND WATCH FOR MUCH OF THE AREA.
TONIGHT...WE MAY SEE A STRONG...THOUGH BRIEF...BAROCLINIC BAND SET
UP OVER OUR CENTRAL ZONES FROM ROUNDUP TO BROADUS DUE TO WARM AIR
ADVECTION TO THE WEST AND COLD ADVECTION COMING IN FROM THE
NORTHWEST OVER NORTHEAST MONTANA. CROSS SECTIONS ALSO A PERIOD OF
HEAVY SNOW POSSIBLE OVER THE WEST FACING SLOPES IN THE HIGH
COUNTRY. OTHERWISE DOWNSLOPE WILL REMAIN A FACTOR FOR MANY AREAS
NEAR THE MOUNTAINS AND FOOTHILLS.
THURSDAY...140 KT JET MAX NOSES INTO THE REGION RIGHT OVER
SOUTHERN MONTANA. ASSOCIATED FORCING WILL PRODUCE A SLIGHT CHANCE
OF PRECIP AT THE LOWER ELEVATIONS. HOWEVER THE MAIN THREAT WILL BE
WIND ON THURSDAY. STRONG COLD AIR ADVECTION WILL SPREAD INTO THE
AREA FROM THE NORTHWEST AT 700 MB. THIS WILL ALLOW A BETTER
OPPORTUNITY TO MIX DOWN THE STRONG WINDS ALOFT AS LAPSE RATES WILL
BE TWICE WHAT THEY ARE TODAY IN THE LOWER LEVELS. HAVE ADDED THE
EASTERN ZONES TO THE HIGH WIND WATCH FOR THURSDAY AS THE STRONGEST
WINDS AND STEEPEST PROGGED LAPSE RATES AFFECT THESE ZONES WITH 850
MB WINDS 55 TO 60 KTS. EXPECT WINDS TO QUICKLY SUBSIDE AFTER DARK
THURSDAY EVENING. BT
.LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE...
EXTENDED FORECAST CONTINUES TO LOOK WINDY AND MILD OVERALL WITH
MODELS BEING IN GOOD AGREEMENT UNTIL THE MIDDLE OF NEXT WEEK.
RIDGE OF HIGH PRESSURE WILL BE OVER THE STATE FRIDAY ALONG WITH A
STRONG LEE-SIDE TROUGH. THIS WILL BRING VERY WINDY CONDITIONS
ACROSS THE ENTIRE FORECAST AREA WITH MILD TEMPERATURES. MODELS
BRING A STRONG TROUGH AND COLD FRONT ACROSS THE FORECAST AREA
SATURDAY BRINGING A CHANCE OF RAIN AND SNOW SHOWERS TO THE PLAINS
WITH VERY WINDY CONDITIONS POSSIBLE. WINDS WILL SUBSIDE ON SUNDAY
WITH TEMPERATURES RETURNING BACK TO NORMAL LEVELS FOR THIS TIME
OF YEAR. RIDGING THEN BEGINS TO BUILD BACK ONCE AGAIN SUNDAY
NIGHT INTO MONDAY BRINGING CONTINUED DRY CONDITIONS AND A RETURN
TO ABOVE NORMAL TEMPERATURES. IN GENERAL FOR MONDAY INTO THE
MIDDLE OF NEXT WEEK...A FAST FLOW ALOFT WILL CONTINUE WITH
ALTERNATING RIDGING AND TROUGHING AS SEVERAL SYSTEMS MOVE OVER
THE FORECAST AREA. LEE-SIDE TROUGHING WILL BE IN PLACE AT TIMES
AS WELL RESULTING IN PERIODS OF STRONG GUSTY WINDS. HOOLEY
&&
.AVIATION...
STRONG AND GUSTY WINDS WILL CONTINUE FROM BIG TIMBER TO KLVM AND
THE ADJACENT FOOTHILLS TODAY. GUSTS OVER 65 KNOTS WILL BE LIKELY
ACROSS THESE AREAS. STRONG AND GUSTY WINDS ARE ALSO EXPECTED TO
SPREAD EASTWARD TO KBIL THIS AFTERNOON WITH GUSTS AROUND 55 KTS.
SNOW WILL IMPACT AREA MOUNTAINS TODAY AND TONIGHT. MOUNTAINS
OBSCURATIONS CAN BE EXPECTED. VFR CONDITIONS CAN BE EXPECTED OVER
THE PLAINS. RICHMOND
&&
.PRELIMINARY POINT TEMP/POPS...
TDY THU FRI SAT SUN MON TUE
-------------------------------------------------------
BIL 053 036/053 030/049 032/043 023/037 023/045 029/044
3/W 42/W 22/W 21/N 10/B 00/B 00/B
LVM 050 040/049 033/049 034/039 019/036 022/044 032/043
2/J 44/W 23/W 21/N 10/B 00/B 00/B
HDN 058 032/057 026/053 026/044 019/037 018/047 025/046
3/W 43/W 21/B 21/N 00/B 00/U 00/B
MLS 054 032/053 027/049 029/041 020/036 018/044 025/045
4/W 23/W 11/B 11/N 00/B 00/U 00/B
4BQ 054 031/054 026/050 027/043 020/038 018/046 024/047
3/W 23/W 21/B 21/N 10/B 00/U 00/U
BHK 050 029/049 025/046 031/038 017/032 016/041 025/042
2/W 23/W 11/B 11/N 10/B 00/U 00/U
SHR 048 027/048 024/046 030/041 016/035 015/042 023/043
2/W 23/W 21/B 22/J 10/B 00/B 00/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...HIGH WIND WARNING IN EFFECT UNTIL 8 PM MST THIS EVENING FOR
ZONES 28-29-34-35-39-41-42.
HIGH WIND WATCH IN EFFECT FROM THURSDAY MORNING THROUGH
THURSDAY AFTERNOON FOR ZONES 28>39-41-42-57-58.
HIGH WIND WARNING IN EFFECT UNTIL 11 AM MST FRIDAY FOR ZONES
65-66.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS