Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/22/14
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
306 AM PST THU NOV 20 2014
.SYNOPSIS...ANOTHER STORM SYSTEM OVER THE EASTERN PACIFIC WILL
BRING RAIN TO THE REGION TODAY. UNSETTLED CONDITIONS WILL THEN
CONTINUE THROUGH SATURDAY WHEN ANOTHER...POTENTIALLY STRONGER
SYSTEM MOVES INTO THE NORTH BAY FRIDAY NIGHT AND SATURDAY MORNING.
&&
.DISCUSSION...AS OF 3:06 AM PST THURSDAY...SATELLITE IMAGERY
SHOWS CLOUDS MOVING ACROSS NORTHERN CALIFORNIA ASSOCIATED WITH AN
APPROACHING LOW PRESSURE SYSTEM. THIS SYSTEM WILL BRING RAIN
SHOWERS TO THE AREA THIS MORNING. THE NORTH BAY IS EXPECTED TO SEE
PRECIP BEGINNING BEFORE NOON...AND SHOWERS WILL THEN SPREAD SOUTH
THROUGH THE SAN FRANCISCO BAY AREA DURING THE THE AFTERNOON. THE
SHOWERS WILL THEN REACH MONTEREY AND SAN BENITO COUNTIES BY LATE
AFTERNOON...AND THEN TAPER OFF DURING THE EVENING AND OVERNIGHT.
PROJECTED RAINFALL TOTALS WITH TODAY`S SYSTEM RANGE FROM UP TO A
HALF INCH ACROSS THE NORTH BAY...TO UNDER A QUARTER OF AN INCH
ACROSS THE SAN FRANCISCO BAY AREA...TO UNDER A TENTH OF AN INCH
ACROSS THE SOUTHERN THIRD OF THE CWA.
THE NEXT STORM SYSTEM WILL REACH THE NORTH BAY BY LATE FRIDAY
NIGHT AND SATURDAY MORNING. LATEST MODEL GUIDANCE SHOWS MODERATE TO
POSSIBLY OCCASIONALLY HEAVIER RAIN OVER THE NORTH BAY WITH LESSER
AMOUNTS TO THE SOUTH. UP TO 1" OF RAIN IS POSSIBLE IN THE NORTH BAY
VALLEYS...WITH 2"-3" RAIN POSSIBLE IN THE NORTH BAY MOUNTAINS.
LESSER AMOUNTS ARE FORECAST SOUTH...POSSIBLY AROUND 1/2" IN THE
SANTA CRUZ MOUNTAINS AND SANTA LUCIA MTN RANGE. SHOWERS TO END
OVERNIGHT WITH HIGH PRESSURE BUILDING OVER THE COAST BY SUNDAY.
THIS RIDGE IS PROGGED TO BUILD OVER THE EASTERN PACIFIC AND RESULT
IN A DRYING TREND THAT WILL EXTEND INTO NEXT WEEK. MEDIUM RANGE
MODELS HINT AT THE RIDGE BREAKING DOWN LATE IN THE WEEK.
&&
.AVIATION...AS OF 9:52 PM PST WEDNESDAY...FOR 06Z TAFS. MAIN
CONCERN FOR OVERNIGHT HOURS AND MORNING HOURS OF THURSDAY WILL BE
EXTENSIVE LEFT OVER BOUNDARY LAYER MOISTURE THAT WILL LEAD TO MVFR
CIGS AND AREAS OF FOG ALONG WITH PATCHY DRIZZLE/LIGHT RAIN.
SOUTHEAST FLOW WILL DEVELOP EARLY THURSDAY AS NEXT SYSTEM WILL
QUICKLY APPROACH FROM NW. 06Z PACKAGE FOLLOWED RAP MODEL WITH
BRINGING RAIN INTO NORTH BAY BEFORE LUNCHTIME WHICH IS EVEN FASTER
THAN THE NAM SOLUTIONS. CURRENT SATELLITE TRENDS SUGGEST FASTER
ARRIVAL OF RAIN LOOKS GOOD.
VICINITY OF KSFO...EXPECTING MVFR CIGS TO REDEVELOP BY MORNING
WITH LIGHT SE WINDS. LATEST TAF SHOWS -RA DEVELOPING BY 19Z.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...LOW CIGS EXPECTED TO REFORM BY
MORNING WITH POSSIBLE REDUCED VSBYS. SLOW IMPROVEMENT THURSDAY
MORNING WITH RAIN DEVELOPING BY AFTERNOON HOURS.
&&
.MARINE...AS OF 2:21 AM PST THURSDAY...WINDS OVER THE COASTAL
WATERS WILL GRADUALLY BECOME MORE SOUTHERLY TODAY AS ANOTHER STORM
SYSTEM APPROACHES THE BAY AREA. RAIN AND POSSIBLY THUNDER WILL
DEVELOP OVER THE NORTHERN WATERS BY MID MORNING WITH WINDS TURNING
NW BEHIND THE FRONT THURSDAY EVENING. SOUTHERLY WINDS WILL DEVELOP
AGAIN FRIDAY AS A STRONGER SYSTEM PASSES TO OUR NORTH BEFORE
MOVING SOUTHWARD OVER THE WATERS SATURDAY WITH RAIN AND INCREASING
WINDS.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
$$
PUBLIC FORECAST: SIMS
AVIATION: RWW
MARINE: MM
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
952 PM PST WED NOV 19 2014
.SYNOPSIS...A FEW SHOWERS LINGER OVER THE AREA THIS EVENING. ANOTHER
STORM SYSTEM OVER THE EASTERN PACIFIC WILL BRING RAIN BACK TO THE
REGION ON THURSDAY. UNSETTLED CONDITIONS WILL THEN PERSIST THROUGH
SATURDAY WHEN ANOTHER...POTENTIALLY STRONGER SYSTEM MOVES INTO THE
NORTH BAY FRIDAY NIGHT AND SATURDAY MORNING.
&&
.DISCUSSION...AS OF 9:20 PM PST WEDNESDAY...KMUX RADAR SHOWS A FEW
REMAINING SHOWERS AROUND THE AREA THIS EVENING. A FEW ADDITIONAL
MOSTLY WIDELY SCATTERED SHOWERS ARE STILL POSSIBLE OVERNIGHT. THE
UPPER TROUGH AND SURFACE COLD FRONT CONTINUE TO MOVE EASTWARD OVER
THE CENTRAL VALLEY AND DISSIPATE THIS EVENING. THERE`LL BE PATCHY
FOG INLAND AND OVER THE COASTAL SECTIONS OVERNIGHT DUE TO THE AIR
MASS BEING MOISTENED FROM THE RECENT RAIN.
THE NEXT TROUGH IS LOCATED OVER THE EASTERN PACIFIC NEAR 42.8N AND
133.8W AND IS FORECAST TO MOVE RAPIDLY SOUTHEAST TO THE BAY AREA BY
EARLY THURSDAY MORNING. SHOWERS WILL DEVELOP ONCE AGAIN AND SOME MAY
BE MODERATE TO HEAVY AS INSTABILITY INCREASES THROUGH THE DAY
ESPECIALLY OVER THE MILDER WATER RESULTING IN STEEPER VERTICAL TEMP
LAPSE RATES. SHOWERS WILL SPREAD SOUTHEAST OVER THE ENTIRE AREA
THROUGH LATE THURSDAY MORNING AND AFTERNOON. THE 00Z NAM MODEL
SHOWS THE NORTH BAY PICKING UP THE MOST RAINFALL WITH UPWARDS OF
0.75" AND UNLIKE EARLIER TODAY`S HIGH VARIABILITY FROM VALLEY TO
MOUNTAIN RAIN REPORTS...THURSDAY`S TROUGH SHOULD PRODUCE MORE
WIDESPREAD AND BENEFICIALLY MEASURABLE RAINFALL OVER THE REMAINDER
OF THE BAY AREA...MORE TYPICAL OF COLDER TROUGHS AND COLD AIR
ADVECTION. THE TROUGH WILL MOVE QUICKLY SOUTHEAST BRINGING
LESSER AMOUNTS OF RAINFALL (0.10" - 0.25")...TO THE NORTH CENTRAL
COAST BY THURSDAY AFTERNOON. AGAIN HIGHER TERRAIN MAY PICK UP A
BIT MORE...NEAR 1/2" BUT THAT WOULD BE LOCALIZED TO HIGHER
MOUNTAIN PEAKS. THE TROUGH WILL REACH SOCAL AND SOUTHERN NV BY
EARLY FRIDAY MORNING.
THE NEXT CHANCE OF RAIN WILL REACH THE NORTH BAY BY LATE FRIDAY
NIGHT AND SATURDAY MORNING. MODEL DATA SHOW MODERATE TO POSSIBLY
OCCASIONALLY HEAVIER RAIN OVER THE NORTH BAY AND THEN AS THE SYSTEM
SLIDES SOUTHEAST THE RAIN TOTALS DISSIPATE BY THE TIME THEY REACH
THE NORTH CENTRAL COAST. UP TO 1" RAIN IS POSSIBLE NORTH BAY
VALLEYS...AND 2"-3" RAIN POSSIBLE IN THE NORTH BAY MOUNTAINS...BUT
LESSER AMOUNTS ARE FORECAST TO THE SOUTH...POSSIBLY AROUND 1/2" IN
THE SANTA CRUZ MOUNTAINS AND SANTA LUCIA MTN RANGE. LOW CONFIDENCE
PERSISTS ON THE QPF FORECAST DUE TO RECENT AND CONTINUED MODEL
DISAGREEMENTS.
FORECAST UPDATED TO INCLUDE PATCHY FOG FOR TONIGHT.
&&
.PREVIOUS DISCUSSION...AS OF 1:51 PM PST WEDNESDAY...ISOLATED TO
SCATTERED RAIN SHOWERS CONTINUE TO MOVE ACROSS THE REGION THIS
AFTERNOON AS A SLOW MOVING FRONTAL BOUNDARY PUSHES INLAND. LIGHT
PRECIPITATION MAY LINGER INTO THE EVENING...YET WILL DIMINISH
TONIGHT WHEN THE MID/UPPER LEVEL TROUGH SHIFTS EASTWARD. WEAK
ONSHORE FLOW WILL THEN DEVELOP IN WAKE OF THE FRONTAL PASSAGE AND
KEEP OVERNIGHT TEMPERATURES ABOVE SEASONAL AVERAGES.
ANOTHER WEAK MID/UPPER LEVEL SYSTEM WILL THEN PUSH INTO THE PACIFIC
NORTHWEST ON THURSDAY...BRINGING RAIN BACK TO MUCH OF THE REGION.
LIGHT RAIN WILL DEVELOP FIRST OVER THE NORTH BAY DURING THE MORNING
HOURS AND SHIFT SOUTHWARD THROUGH THE AFTERNOON. WILL CARRY A SLIGHT
CHANCE OF THUNDERSTORMS OVER THE COASTAL WATERS FOR TOMORROW
AFTERNOON GIVEN THE COLDER AIR MASS ALOFT...STRONG UPPER LEVEL JET
JUST OFF THE COAST AND INCREASED INSTABILITY FORECAST BY THE
GFS/NAM. SIMILAR TO THE SYSTEM CURRENTLY PUSHING INLAND...RAINFALL
AMOUNTS ON THURSDAY WILL GENERALLY REMAIN LIGHT. HOWEVER...THE
ARW/NMM BOTH SUGGEST STRONGER CONVECTIVE CELLS DEVELOPING OVER THE
COASTAL WATERS DURING THE AFTERNOON. IF THIS DOES OCCUR AND
CONVECTION HOLDS TOGETHER WHILE PUSHING INLAND...CANNOT RULE OUT
SOME MODERATE SHOWERS WITH ISOLATED HIGHER RAINFALL AMOUNTS.
SHOWERS WILL THEN TAPER OFF THURSDAY NIGHT INTO EARLY FRIDAY
MORNING.
THE FORECAST MODELS THEN SHOW A STRONGER UPPER LEVEL JET
DEVELOPING AND EXTENDING INTO THE PACIFIC NORTHWEST AND NORTHERN
CALIFORNIA FRIDAY NIGHT INTO SATURDAY. IN ADDITION...A DEEPER
MOISTURE POOL WITH PWAT VALUES BETWEEN 1.20" TO 1.50" IS SET TO
ADVECT INTO NORTHERN CALIFORNIA DURING THIS TIME...LIKELY SETTING
THE STAGE FOR HEAVIER RAIN. AT THIS TIME...IT APPEARS THE NORTH
BAY WILL RECEIVE THE GREATEST RAINFALL AMOUNTS FRIDAY NIGHT INTO
SATURDAY WHEN WEAK MID/UPPER LEVEL DISTURBANCES MOVE THROUGH THE
MEAN FLOW. DO EXPECT SOME SOUTHWARD PROGRESS OF THE SYSTEM THAT
WILL HELP SPREAD RAIN DOWN INTO THE SAN FRANCISCO BAY AREA AND
POINTS SOUTHWARD. HOWEVER...LESSER RAINFALL AMOUNTS ARE FORECAST
FURTHER SOUTH AS THE DEEPER MOISTURE GETS REPLACED BY A DRIER AIR
MASS. SHOWERS MAY LINGER THROUGH THE AFTERNOON ON SATURDAY...YET
DRIER CONDITIONS RETURN SATURDAY NIGHT INTO SUNDAY.
A RIDGE OF HIGH PRESSURE IS THEN FORECAST TO DEVELOP OVER THE
PACIFIC AND BUILD TOWARD THE COAST EARLY NEXT WEEK. THIS WILL RESULT
IN DRY WEATHER CONDITIONS AND A SLOW WARMING TREND IN TEMPERATURES
BACK TO ABOVE SEASONAL AVERAGES FOR THE FIRST HALF OF NEXT WEEK.
MODEL CONSISTENCY THEN DIVERGES BY WEDNESDAY INTO LATE NEXT WEEK
WITH THE ECMWF BREAKING THE RIDGE DOWN WEDNESDAY AND BRINGING
ANOTHER SYSTEM INTO THE PACIFIC NORTHWEST. MEANWHILE...THE GFS KEEPS
THE RIDGE IN PLACE WITH A BREAK DOWN NOT OCCURRING UNTIL LATE NEXT
WEEK. FOR NOW...WILL KEEP DRY CONDITIONS FOR DAY 7 AND 8.
&&
.AVIATION...AS OF 9:52 PM PST WEDNESDAY...FOR 06Z TAFS. MAIN
CONCERN FOR OVERNIGHT HOURS AND MORNING HOURS OF THURSDAY WILL BE
EXTENSIVE LEFT OVER BOUNDARY LAYER MOISTURE THAT WILL LEAD TO MVFR
CIGS AND AREAS OF FOG ALONG WITH PATCHY DRIZZLE/LIGHT RAIN.
SOUTHEAST FLOW WILL DEVELOP EARLY THURSDAY AS NEXT SYSTEM WILL
QUICKLY APPROACH FROM NW. 06Z PACKAGE FOLLOWED RAP MODEL WITH
BRINGING RAIN INTO NORTH BAY BEFORE LUNCHTIME WHICH IS EVEN FASTER
THAN THE NAM SOLUTIONS. CURRENT SATELLITE TRENDS SUGGEST FASTER
ARRIVAL OF RAIN LOOKS GOOD.
VICINITY OF KSFO...EXPECTING MVFR CIGS TO REDEVELOP BY MORNING
WITH LIGHT SE WINDS. LATEST TAF SHOWS -RA DEVELOPING BY 19Z.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...LOW CIGS EXPECTED TO REFORM BY
MORNING WITH POSSIBLE REDUCED VSBYS. SLOW IMPROVEMENT THURSDAY
MORNING WITH RAIN DEVELOPING BY AFTERNOON HOURS.
&&
.MARINE...AS OF 9:45 PM PST WEDNESDAY...WINDS WILL BRIEFLY TURN
WESTERLY OVERNIGHT BEFORE SOUTHERLY WINDS DEVELOP ONCE AGAIN
THURSDAY MORNING AS A FAST MOVING SYSTEM MOVES IN FROM THE NW.
RAIN WILL DEVELOP OVER THE NORTHERN WATERS BY MID MORNING WITH
WINDS TURNING NW BEHIND THE FRONT THURSDAY EVENING. SOUTHERLY
WINDS WILL DEVELOP AGAIN FRIDAY AS A STRONGER SYSTEM PASSES TO OUR
NORTH BEFORE DROPPING SOUTHWARD OVER THE WATERS SATURDAY WITH RAIN
AND INCREASING WINDS. NW WIND AND SEAS WILL DEVELOP SATURDAY NIGHT
INTO SUNDAY.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...NONE.
$$
PUBLIC FORECAST: CANEPA/RGASS
AVIATION/MARINE: RWW
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AREA FORECAST DISCUSSION
NWS ALBANY NY
526 PM EST THU NOV 20 2014
.SYNOPSIS...
LOW PRESSURE WILL MOVE INTO THE CANADIAN MARITIMES
TONIGHT. LAKE EFFECT SNOW WILL IMPACT THE WESTERN ADIRONDACKS AND
THE MOHAWK VALLEY OVERNIGHT INTO FRIDAY MORNING. HIGH PRESSURE WILL
BRIEFLY BUILD IN FROM THE OHIO VALLEY AND MID ATLANTIC REGION FRIDAY
NIGHT INTO SATURDAY. A WARM FRONT WILL BRING SOME LIGHT MIXED
PRECIPITATION TO THE REGION SATURDAY INTO SUNDAY...AS A MILDER AIR
MASS BUILDS IN TO CLOSE THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 526 PM EST...A LAKE EFFECT SNOW WARNING REMAINS IN EFFECT
FOR NORTHERN HERKIMER AND HAMILTON COUNTIES UNTIL 10 AM EDT...WITH
A LAKE EFFECT ADVISORY FOR SOUTHERN HERKIMER COUNTY FROM MIDNIGHT
UNTIL NOONTIME.
A QUICK UPDATE WITH THE ISOLD SNOW SHOWERS/BRIEF SQUALLS MOVING
ACROSS THE ERN MOHAWK VALLEY AND CAPITAL REGION BTWN 5-6 PM. SOME
COATINGS TO FEW TENTHS OF AN INCH OF SNOWFALL WILL BE POSSIBLE
WITH THE SNOW SHOWERS/SQUALLS.
PREVIOUS NEAR TERM...
A COLD FRONT CONTINUES TO MOVE ACROSS
SOUTHEASTERN NY AND NEW ENGLAND LATE THIS AFTERNOON INTO EARLY
THIS EVENING. ISOLD-SCT SNOW SHOWERS AND FLURRIES HAVE OCCURRED
OVER THE NRN CATSKILLS...CAPITAL REGION...AND THE BERKSHIRES. A
MORE IMPRESSIVE LAKE EFFECT SNOWBAND CONTINUES TO EXTEND
DOWNSTREAM INTO THE WRN ADIRONDACKS OFF LAKE ONTARIO. THIS INTENSE
LAKE EFFECT BAND IS RIGHT ON SCHEDULE WITH BURSTS OF LOCALIZED
HEAVY SNOW FOR THE NRN TIP OF HERKIMER CTY...AND NW HAMILTON
COUNTY. THE CRITICAL LAKE EFFECT PARAMETERS ARE IN PLACE FOR HEAVY
LAKE EFFECT SNOWFALL FOR THE WRN DACKS. A SINGLE BAND HAS FORMED
WITH LIMITED LOW TO MID LEVEL SHEAR AND THE LOW LEVEL FLOW SLOWLY
VEERING TO A 250-270 DEG TRAJECTORY. LAKE/ATMO DELTA TEMPS ARE
FAVORABLE WITH EXTREME LAKE INSTABILITY FAVORED BY THE UPSTREAM
BUFKIT SOUNDINGS NEAR THE TUG HILL PLATEAU AND THE W-CNTRL MOHAWK
VALLEY.
1 TO 2 INCH PER HOUR SNOWFALL RATES ARE LIKELY FROM EARLY THIS
EVENING INTO THE EARLY MORNING HOURS. THE MESOSCALE MODELS AND THE
3-KM HRRR INDICATING THE FLOW VEERING...AND THE BAND PIVOTING S/SE
INTO THE MOHAWK VALLEY BTWN 06Z-12Z. WE ARE EXPECTING WARNING
LEVEL SNOWFALL FROM OLD FORGE...EAGLE BAY...AND INLET NORTH AND
WEST WITH 8-16 INCHES POSSIBLE. FURTHER SOUTH IN THE WARNING AREAS
EXPECT 6-12 INCHES. THE LAKE EFFECT ADVISORY AREA WILL RECEIVE 2
TO 6 INCHES. THE BAND LOOKS LIKE IT WILL CRUMBLE SHORTLY AFTER
12Z...AND THE NW FLOW TRAJECTORY FAVOR MULTI BANDS.
ELSEWHERE...COLD AND BRISK CONDITIONS WILL DOMINATE WITH SOME
ISOLD-SCT UPSLOPE SNOW SHOWERS OVER THE SRN GREENS. TEMPS WILL BE
BELOW NORMAL IN THE ARCTIC AIR MASS. LOWS WILL BE IN THE TEENS AND
L20S WITH A FEW SPOTTY SINGLE DIGIT READINGS OVER THE SRN GREENS
AND SRN DACKS.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
TOMORROW...THE LAKE EFFECT ACTIVITY CONTINUES AS MULTIBANDS OVER
CNTRL NY. SOME OF THE SNOW SHOWERS MAY SNEAK INTO THE MOHAWK RIVER
VALLEY...AND THE NRN AND ERN CATSKILLS. LIGHT SNOW ACCUMS ARE
EXPECTED. THE LOWERING INVERSION ON THE KUCA/KRME SOUNDINGS
INDICATE THAT ACTIVITY SHOULD BE LESS. OUR HEADLINES ONLY RUN TO
10 AM/WARNING/ AND NOON /ADVISORY/. H850 TEMPS WILL BE A FEW STD
DEVS BELOW NORMAL WITH THE GFS HAVING H850 TEMPS OF -14C TO -16C.
MIXED CLOUDS AND SUNSHINE WITH COLD AND BLUSTERY CONDITIONS WILL
PREVAIL WITH HIGHS IN THE 20S TO L30S OVER MOST OF THE
REGION...WITH SOME TEENS OVER THE SRN DACKS. A FEW M30S WILL BE
POSSIBLE IN THE MID HUDSON VALLEY.
FRIDAY NIGHT INTO SATURDAY...MAINLY QUIET AND COLD WEATHER WILL
CONTINUE AS A SFC HIGH BUILDS IN FROM THE SOUTH. THE SFC
ANTICYCLONE WILL BE CENTERED OVER THE OH VALLEY FRIDAY NIGHT...AND
DRIFT OVER THE MID ATLANTIC REGION BY SATURDAY. THE LAST VESTIGES
OF THE LAKE EFFECT WILL END WITH THE FLOW BACKING AND THE BAND
LIFTING NORTHWARD ACROSS CNTRL NY. SOME WEAK LOW TO MID LEVEL WARM
ADVECTION WILL ALSO BE OCCURRING. A DECENT RADIATIONAL COOLING NIGHT
WILL SET UP WITH LOWS MAINLY IN THE TEENS WITH SOME SINGLE DIGITS
OVER THE SRN DACKS AND SRN GREENS. SATURDAY...THE SFC HIGH WILL
BUILD IN FROM THE SOUTH WITH FAIR AND DRY WEATHER TO START THE
DAY. LOW LEVEL WARM ADVECTION WILL CONTINUE WITH HIGHS IN THE
LOWER TO M30S OVER THE HILLS AND MTNS...AND M30S TO L40S IN THE
VALLEYS. MID AND HIGH CLOUDS WILL INCREASE LATE IN THE DAY FROM
THE W/SW WELL IN ADVANCE OF WARM FRONT OVER THE GREAT LAKES REGION
AND MIDWEST.
SATURDAY NIGHT...SOME TIMING DIFFERENCES FROM THE GUIDANCE WITH
LIGHT PCPN WITH THE ISENTROPIC LIFT AHEAD OF THE WARM FRONT AND
THE MID LEVEL IMPULSE. LIGHT SPOTTY MIXED PCPN IS POSSIBLE BASED
ON THE GFS/NAM BUFKIT SOUNDINGS. ALSO...A BLEND OF THE ECMWF/GFS
CRITICAL THICKNESSES SUPPORT A LIGHT MIX OF SNOW/SLEET/FREEZING
RAIN OVERNIGHT. SLIGHT AND LOW CHC POPS WERE MAINLY USED FOR MOST
OF THE REGION WITH A SMALL AREA OF LIKELY VALUES OVER THE WRN
DACKS. AN ADVISORY MAY BE NEEDED LATER IN TIME. LOWS WILL BE EARLY
ON IN THE EVENING IN THE 20S FOR MOST LOCATIONS...THEN RISE
TOWARDS DAYBREAK.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
THE PERIOD STARTS OUT SUNDAY WITH A WARM FRONT LIFTING NORTHWARD
ACROSS THE REGION. WITH RIDGING BUILDING THERE WILL BE DECREASING
CHANCES FOR ANY PRECIP...SO WILL ONLY MENTION SLIGHT CHANCE FOR A
FEW LIGHT SHOWERS DURING THE FIRST HALF OF THE DAY WITH DRY
CONDITIONS DURING THE AFTERNOON. WITH A FEW BREAKS OF SUNSHINE
POSSIBLE AND A SOUTHERLY FLOW DEVELOPING...TEMPERATURES ARE EXPECTED
TO WARM WELL INTO THE 40S ACROSS MUCH OF THE AREA WITH NEAR 50
DEGREE READINGS IN THE MID HUDSON VALLEY.
SUNDAY NIGHT INTO MONDAY MORNING WILL BE AN ACTIVE PERIOD IN TERMS
OF PRECIPITATION ACROSS THE ENTIRE REGION...AS A POWERFUL STORM
TRACKS NORTHWARD FROM THE MIDWEST THROUGH THE UPPER GREAT LAKES WITH
A SURGE OF MOISTURE AND A FRONTAL BOUNDARY MOVING NORTHWARD ACROSS
THE NORTHEAST. A STRONG SOUTHERLY LOW LEVEL JET DEVELOPING WILL
ALLOW FOR TEMPERATURES TO BE WARM ENOUGH FOR ALL RAIN. MODELS IN
FAIRLY GOOD AGREEMENT SHOWING AROUND ONE HALF TO ONE INCH OF
RAINFALL.
MONDAY AFTERNOON MAY TURN OUT TO BE MOSTLY DRY AS ANOTHER WARM FRONT
LIFTS NORTH OF THE REGION. WITH A S/SW FLOW AND WARM AIR ALOFT
MOVING IN THERE WILL LIKELY BE ENOUGH MIXING TO RESULT IN TEMPS
REACHING THE UPPER 50S TO LOWER 60S IN MOST VALLEY LOCATIONS DESPITE
LIMITED SUNSHINE. THEN THE FIRST IN A SERIES OF COLD FRONTS IS
EXPECTED TO PASS THROUGH THE REGION MONDAY NIGHT...ALTHOUGH
TEMPERATURES WILL STILL BE RELATIVELY MILD WITH THE FLOW ALOFT
REMAINING SOUTHWEST WITH A SLIGHTLY COOLER AIR MASS MOVING IN.
AN ADDITIONAL COLD FRONT WILL PASS THROUGH LATE TUESDAY INTO
WEDNESDAY...WITH FURTHER COOLING ALLOWING TEMPERATURES TO GET BACK
TO NEAR NORMAL LEVELS. SOMETHING TO WATCH FOR WEDNESDAY WILL BE
POTENTIAL CYCLOGENESIS OFF THE EASTERN SEABOARD AS ENERGY MOVES
ACROSS A QUASI-STATIONARY BAROCLINIC ZONE. MOST SOURCES OF MODEL
GUIDANCE INDICATING DEVELOPMENT WILL BE TOO FAR OFFSHORE TO HAVE AN
IMPACT IN OUR REGION...BUT A FEW MODELS ARE SHOWING SOME POSSIBLE
RAIN/SNOW ON THE NORTHWEST PERIPHERY OF THIS SYSTEM. MAINLY DRY AND
COLDER WEATHER IS THEN EXPECTED FOR THANKSGIVING DAY.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
AS OF 1730Z...WINDS HAVE SHIFTED AT THE AIRPORTS RIGHT BEHIND
ANOTHER ARCTIC COLD FRONT. WESTERLY WINDS WILL BE RATHER STRONG AND
GUSTY UNTIL DARK...THEN STILL IN THE 7 TO 10 KNOTS RANGE THEREAFTER.
THE PRESSURE GRADIENT TIGHTENS OVERNIGHT...WITH WINDS BY MIDDAY IN
THE 12 TO 15 KNOTS RANGE WITH GUSTS TO 25 KNOTS. THIS WILL TURN ON
THE LAKE EFFECT MACHINE ONCE AGAIN...WHICH WILL HAVE MINIMAL IMPACT
AT THE AIRPORTS DUE TO THE RAPIDLY DRYING CONDITIONS AND DOWNSLOPING
NOW TAKING PLACE THROUGH THE COLUMN. THUS...ANY SNOW ALOFT WILL
HAVE TROUBLE REACHING THE GROUND BEFORE DISSIPATING.
ONCE LAKE EFFECT BANDS GET ORGANIZED TO OUR WEST THROUGH EARLY THIS
EVENING...THE SNOW WILL BECOME MORE FOCUSED...WITH KGFL MOST PRONE
TO SEEING PERHAPS A FEW FLURRIES FROM THESE BANDS WHICH WILL HAVE
DUMPED A GREAT DEAL OF THE MOISTURE TO THE WEST OVER THE TUG HILL
PLATEAU. HAVE ALSO INCLUDED A PERIOD OF VCSH AT KPSF DUE TO
UPSLOPING INTO THE BERKSHIRE TERRAIN.
MODERATE WIND SHEAR WILL BE AN ISSUE WITH WINDS AS HIGH AS 35 OR 40
KNOTS AT 2000 FEET. DIRECTIONAL SHEAR WILL BE ONLY 20 TO 30
DEGREES. A PERIOD OF THIS HAS BEEN INCLUDED SOUTH OF KGFL...
ANYWHERE WITHIN THE 23Z TO 11Z TIME FRAME. THEN WINDS ABOVE THE
FRICTION LAYER WEAKEN SLIGHTLY AS THE SYSTEM PULLS AWAY AND HIGH
PRESSURE BEGINS TO BUILD IN.
VISIBILITY- AND CLOUD-WISE...WHILE CEILINGS WILL WIN OVER MOST OF
THE TIME NORTH OF KPOU...HEIGHTS WILL BE UP IN THE VFR RANGE. SOME
SCT025 CLOUDS COULD WHIZ BY ANYTIME BEFORE DAYBREAK...BEING MAINLY
LAKE-BAND FRACTUS THAT MAKES IT THIS FAR INLAND. CARRYING SOME VFR
BR OVERNIGHT AT KALB...WHICH WILL BE A COMBINATION OF MOHAWK RIVER
MOISTURE FETCH AND SUBLIMATING LIGHT SNOW AND FLURRIES ALOFT.
WOULDN/T RULE OUT MVFR...BUT IT WILL PROBABLY BE TOO COLD AND DRY
NEAR THE SURFACE.
OUTLOOK...
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...RA...FZRA...SLEET.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
SUNDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA.
MONDAY: HIGH OPERATIONAL IMPACT. LIKELY SHRA.
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO SIGNIFICANT...WIDESPREAD...HYDROLOGIC PROBLEMS ARE EXPECTED
THROUGH TUESDAY.
MAINLY DRY CONDITIONS ARE EXPECTED ACROSS THE HSA THROUGH
SATURDAY...EXCEPT LAKE EFFECT ACTIVITY TONIGHT INTO FRIDAY
AFTERNOON FOR THE WESTERN ADIRONDACK REGION AND THE WESTERN AND
CENTRAL MOHAWK VALLEY.
A WARM FRONT WILL BRING LIGHT MIXED PRECIPITATION TO THE REGION
SATURDAY NIGHT INTO SUNDAY MORNING WITH TOTAL QPF LESS THAN A
QUARTER OF AN INCH.
MILDER AIR WILL MOVE INTO THE REGION SUNDAY INTO NEXT WEEK WITH
AFTERNOON TEMPERATURES REACHING THE MID 40S TO LOW 50S
SUNDAY...50S AND LOW 60S MONDAY AND 50S TUESDAY...WITH NIGHTTIME
LOWS MAINLY ABOVE FREEZING.
A FRONTAL BOUNDARY COULD BRING A HALF AN INCH TO AN INCH OF
RAINFALL TO THE HSA SUNDAY NIGHT INTO MONDAY...WITH ADDITIONAL
SCATTERED SHOWERS TUESDAY. AT THIS POINT NO HYDRO PROBLEMS ARE
EXPECTED WITH THE RAINFALL AND MINOR SNOW MELT ESPECIALLY OVER THE
SOUTHERN ADIRONDACKS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...LAKE EFFECT SNOW WARNING UNTIL 10 AM EST FRIDAY FOR NYZ032-033.
LAKE EFFECT SNOW ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST
FRIDAY FOR NYZ038.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...WASULA
SHORT TERM...WASULA
LONG TERM...JPV
AVIATION...JPV
HYDROLOGY...SNYDER/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
434 PM EST THU NOV 20 2014
.SYNOPSIS...
LOW PRESSURE WILL MOVE INTO THE CANADIAN MARITIMES
TONIGHT. LAKE EFFECT SNOW WILL IMPACT THE WESTERN ADIRONDACKS AND
THE MOHAWK VALLEY OVERNIGHT INTO FRIDAY MORNING. HIGH PRESSURE WILL
BRIEFLY BUILD IN FROM THE OHIO VALLEY AND MID ATLANTIC REGION FRIDAY
NIGHT INTO SATURDAY. A WARM FRONT WILL BRING SOME LIGHT MIXED
PRECIPITATION TO THE REGION SATURDAY INTO SUNDAY...AS A MILDER AIR
MASS BUILDS IN TO CLOSE THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 430 PM EST...A LAKE EFFECT SNOW WARNING REMAINS IN EFFECT
FOR NORTHERN HERKIMER AND HAMILTON COUNTIES UNTIL 10 AM EDT...WITH A
LAKE EFFECT ADVISORY FOR SOUTHERN HERKIMER COUNTY FROM MIDNIGHT
UNTIL NOONTIME.
A COLD FRONT CONTINUES TO MOVE ACROSS SOUTHEASTERN NY AND NEW
ENGLAND LATE THIS AFTERNOON INTO EARLY THIS EVENING. ISOLD-SCT
SNOW SHOWERS AND FLURRIES HAVE OCCURRED OVER THE NRN
CATSKILLS...CAPITAL REGION...AND THE BERKSHIRES. A MORE IMPRESSIVE
LAKE EFFECT SNOWBAND CONTINUES TO EXTEND DOWNSTREAM INTO THE WRN
ADIRONDACKS OFF LAKE ONTARIO. THIS INTENSE LAKE EFFECT BAND IS
RIGHT ON SCHEDULE WITH BURSTS OF LOCALIZED HEAVY SNOW FOR THE NRN
TIP OF HERKIMER CTY...AND NW HAMILTON COUNTY. THE CRITICAL LAKE
EFFECT PARAMETERS ARE IN PLACE FOR HEAVY LAKE EFFECT SNOWFALL FOR
THE WRN DACKS. A SINGLE BAND HAS FORMED WITH LIMITED LOW TO MID
LEVEL SHEAR AND THE LOW LEVEL FLOW SLOWLY VEERING TO A 250-270 DEG
TRAJECTORY. LAKE/ATMO DELTA TEMPS ARE FAVORABLE WITH EXTREME LAKE
INSTABILITY FAVORED BY THE UPSTREAM BUFKIT SOUNDINGS NEAR THE TUG
HILL PLATEAU AND THE W-CNTRL MOHAWK VALLEY.
1 TO 2 INCH PER HOUR SNOWFALL RATES ARE LIKELY FROM EARLY THIS
EVENING INTO THE EARLY MORNING HOURS. THE MESOSCALE MODELS AND THE
3-KM HRRR INDICATING THE FLOW VEERING...AND THE BAND PIVOTING S/SE
INTO THE MOHAWK VALLEY BTWN 06Z-12Z. WE ARE EXPECTING WARNING
LEVEL SNOWFALL FROM OLD FORGE...EAGLE BAY...AND INLET NORTH AND
WEST WITH 8-16 INCHES POSSIBLE. FURTHER SOUTH IN THE WARNING AREAS
EXPECT 6-12 INCHES. THE LAKE EFFECT ADVISORY AREA WILL RECEIVE 2
TO 6 INCHES. THE BAND LOOKS LIKE IT WILL CRUMBLE SHORTLY AFTER
12Z...AND THE NW FLOW TRAJECTORY FAVOR MULTI BANDS.
ELSEWHERE...COLD AND BRISK CONDITIONS WILL DOMINATE WITH SOME
ISOLD-SCT UPSLOPE SNOW SHOWERS OVER THE SRN GREENS. TEMPS WILL BE
BELOW NORMAL IN THE ARCTIC AIR MASS. LOWS WILL BE IN THE TEENS AND
L20S WITH A FEW SPOTTY SINGLE DIGIT READINGS OVER THE SRN GREENS
AND SRN DACKS.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
TOMORROW...THE LAKE EFFECT ACTIVITY CONTINUES AS MULTIBANDS OVER
CNTRL NY. SOME OF THE SNOW SHOWERS MAY SNEAK INTO THE MOHAWK RIVER
VALLEY...AND THE NRN AND ERN CATSKILLS. LIGHT SNOW ACCUMS ARE
EXPECTED. THE LOWERING INVERSION ON THE KUCA/KRME SOUNDINGS
INDICATE THAT ACTIVITY SHOULD BE LESS. OUR HEADLINES ONLY RUN TO
10 AM/WARNING/ AND NOON /ADVISORY/. H850 TEMPS WILL BE A FEW STD
DEVS BELOW NORMAL WITH THE GFS HAVING H850 TEMPS OF -14C TO -16C.
MIXED CLOUDS AND SUNSHINE WITH COLD AND BLUSTERY CONDITIONS WILL
PREVAIL WITH HIGHS IN THE 20S TO L30S OVER MOST OF THE
REGION...WITH SOME TEENS OVER THE SRN DACKS. A FEW M30S WILL BE
POSSIBLE IN THE MID HUDSON VALLEY.
FRIDAY NIGHT INTO SATURDAY...MAINLY QUIET AND COLD WEATHER WILL
CONTINUE AS A SFC HIGH BUILDS IN FROM THE SOUTH. THE SFC
ANTICYCLONE WILL BE CENTERED OVER THE OH VALLEY FRIDAY NIGHT...AND
DRIFT OVER THE MID ATLANTIC REGION BY SATURDAY. THE LAST VESTIGES
OF THE LAKE EFFECT WILL END WITH THE FLOW BACKING AND THE BAND
LIFTING NORTHWARD ACROSS CNTRL NY. SOME WEAK LOW TO MID LEVEL WARM
ADVECTION WILL ALSO BE OCCURRING. A DECENT RADIATIONAL COOLING NIGHT
WILL SET UP WITH LOWS MAINLY IN THE TEENS WITH SOME SINGLE DIGITS
OVER THE SRN DACKS AND SRN GREENS. SATURDAY...THE SFC HIGH WILL
BUILD IN FROM THE SOUTH WITH FAIR AND DRY WEATHER TO START THE
DAY. LOW LEVEL WARM ADVECTION WILL CONTINUE WITH HIGHS IN THE
LOWER TO M30S OVER THE HILLS AND MTNS...AND M30S TO L40S IN THE
VALLEYS. MID AND HIGH CLOUDS WILL INCREASE LATE IN THE DAY FROM
THE W/SW WELL IN ADVANCE OF WARM FRONT OVER THE GREAT LAKES REGION
AND MIDWEST.
SATURDAY NIGHT...SOME TIMING DIFFERENCES FROM THE GUIDANCE WITH
LIGHT PCPN WITH THE ISENTROPIC LIFT AHEAD OF THE WARM FRONT AND
THE MID LEVEL IMPULSE. LIGHT SPOTTY MIXED PCPN IS POSSIBLE BASED
ON THE GFS/NAM BUFKIT SOUNDINGS. ALSO...A BLEND OF THE ECMWF/GFS
CRITICAL THICKNESSES SUPPORT A LIGHT MIX OF SNOW/SLEET/FREEZING
RAIN OVERNIGHT. SLIGHT AND LOW CHC POPS WERE MAINLY USED FOR MOST
OF THE REGION WITH A SMALL AREA OF LIKELY VALUES OVER THE WRN
DACKS. AN ADVISORY MAY BE NEEDED LATER IN TIME. LOWS WILL BE EARLY
ON IN THE EVENING IN THE 20S FOR MOST LOCATIONS...THEN RISE
TOWARDS DAYBREAK.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
THE PERIOD STARTS OUT SUNDAY WITH A WARM FRONT LIFTING NORTHWARD
ACROSS THE REGION. WITH RIDGING BUILDING THERE WILL BE DECREASING
CHANCES FOR ANY PRECIP...SO WILL ONLY MENTION SLIGHT CHANCE FOR A
FEW LIGHT SHOWERS DURING THE FIRST HALF OF THE DAY WITH DRY
CONDITIONS DURING THE AFTERNOON. WITH A FEW BREAKS OF SUNSHINE
POSSIBLE AND A SOUTHERLY FLOW DEVELOPING...TEMPERATURES ARE EXPECTED
TO WARM WELL INTO THE 40S ACROSS MUCH OF THE AREA WITH NEAR 50
DEGREE READINGS IN THE MID HUDSON VALLEY.
SUNDAY NIGHT INTO MONDAY MORNING WILL BE AN ACTIVE PERIOD IN TERMS
OF PRECIPITATION ACROSS THE ENTIRE REGION...AS A POWERFUL STORM
TRACKS NORTHWARD FROM THE MIDWEST THROUGH THE UPPER GREAT LAKES WITH
A SURGE OF MOISTURE AND A FRONTAL BOUNDARY MOVING NORTHWARD ACROSS
THE NORTHEAST. A STRONG SOUTHERLY LOW LEVEL JET DEVELOPING WILL
ALLOW FOR TEMPERATURES TO BE WARM ENOUGH FOR ALL RAIN. MODELS IN
FAIRLY GOOD AGREEMENT SHOWING AROUND ONE HALF TO ONE INCH OF
RAINFALL.
MONDAY AFTERNOON MAY TURN OUT TO BE MOSTLY DRY AS ANOTHER WARM FRONT
LIFTS NORTH OF THE REGION. WITH A S/SW FLOW AND WARM AIR ALOFT
MOVING IN THERE WILL LIKELY BE ENOUGH MIXING TO RESULT IN TEMPS
REACHING THE UPPER 50S TO LOWER 60S IN MOST VALLEY LOCATIONS DESPITE
LIMITED SUNSHINE. THEN THE FIRST IN A SERIES OF COLD FRONTS IS
EXPECTED TO PASS THROUGH THE REGION MONDAY NIGHT...ALTHOUGH
TEMPERATURES WILL STILL BE RELATIVELY MILD WITH THE FLOW ALOFT
REMAINING SOUTHWEST WITH A SLIGHTLY COOLER AIR MASS MOVING IN.
AN ADDITIONAL COLD FRONT WILL PASS THROUGH LATE TUESDAY INTO
WEDNESDAY...WITH FURTHER COOLING ALLOWING TEMPERATURES TO GET BACK
TO NEAR NORMAL LEVELS. SOMETHING TO WATCH FOR WEDNESDAY WILL BE
POTENTIAL CYCLOGENESIS OFF THE EASTERN SEABOARD AS ENERGY MOVES
ACROSS A QUASI-STATIONARY BAROCLINIC ZONE. MOST SOURCES OF MODEL
GUIDANCE INDICATING DEVELOPMENT WILL BE TOO FAR OFFSHORE TO HAVE AN
IMPACT IN OUR REGION...BUT A FEW MODELS ARE SHOWING SOME POSSIBLE
RAIN/SNOW ON THE NORTHWEST PERIPHERY OF THIS SYSTEM. MAINLY DRY AND
COLDER WEATHER IS THEN EXPECTED FOR THANKSGIVING DAY.
&&
.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
AS OF 1730Z...WINDS HAVE SHIFTED AT THE AIRPORTS RIGHT BEHIND
ANOTHER ARCTIC COLD FRONT. WESTERLY WINDS WILL BE RATHER STRONG AND
GUSTY UNTIL DARK...THEN STILL IN THE 7 TO 10 KNOTS RANGE THEREAFTER.
THE PRESSURE GRADIENT TIGHTENS OVERNIGHT...WITH WINDS BY MIDDAY IN
THE 12 TO 15 KNOTS RANGE WITH GUSTS TO 25 KNOTS. THIS WILL TURN ON
THE LAKE EFFECT MACHINE ONCE AGAIN...WHICH WILL HAVE MINIMAL IMPACT
AT THE AIRPORTS DUE TO THE RAPIDLY DRYING CONDITIONS AND DOWNSLOPING
NOW TAKING PLACE THROUGH THE COLUMN. THUS...ANY SNOW ALOFT WILL
HAVE TROUBLE REACHING THE GROUND BEFORE DISSIPATING.
ONCE LAKE EFFECT BANDS GET ORGANIZED TO OUR WEST THROUGH EARLY THIS
EVENING...THE SNOW WILL BECOME MORE FOCUSED...WITH KGFL MOST PRONE
TO SEEING PERHAPS A FEW FLURRIES FROM THESE BANDS WHICH WILL HAVE
DUMPED A GREAT DEAL OF THE MOISTURE TO THE WEST OVER THE TUG HILL
PLATEAU. HAVE ALSO INCLUDED A PERIOD OF VCSH AT KPSF DUE TO
UPSLOPING INTO THE BERKSHIRE TERRAIN.
MODERATE WIND SHEAR WILL BE AN ISSUE WITH WINDS AS HIGH AS 35 OR 40
KNOTS AT 2000 FEET. DIRECTIONAL SHEAR WILL BE ONLY 20 TO 30
DEGREES. A PERIOD OF THIS HAS BEEN INCLUDED SOUTH OF KGFL...
ANYWHERE WITHIN THE 23Z TO 11Z TIME FRAME. THEN WINDS ABOVE THE
FRICTION LAYER WEAKEN SLIGHTLY AS THE SYSTEM PULLS AWAY AND HIGH
PRESSURE BEGINS TO BUILD IN.
VISIBILITY- AND CLOUD-WISE...WHILE CEILINGS WILL WIN OVER MOST OF
THE TIME NORTH OF KPOU...HEIGHTS WILL BE UP IN THE VFR RANGE. SOME
SCT025 CLOUDS COULD WHIZ BY ANYTIME BEFORE DAYBREAK...BEING MAINLY
LAKE-BAND FRACTUS THAT MAKES IT THIS FAR INLAND. CARRYING SOME VFR
BR OVERNIGHT AT KALB...WHICH WILL BE A COMBINATION OF MOHAWK RIVER
MOISTURE FETCH AND SUBLIMATING LIGHT SNOW AND FLURRIES ALOFT.
WOULDN/T RULE OUT MVFR...BUT IT WILL PROBABLY BE TOO COLD AND DRY
NEAR THE SURFACE.
OUTLOOK...
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...RA...FZRA...SLEET.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
SUNDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA.
MONDAY: HIGH OPERATIONAL IMPACT. LIKELY SHRA.
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO SIGNIFICANT...WIDESPREAD...HYDROLOGIC PROBLEMS ARE EXPECTED
THROUGH TUESDAY.
MAINLY DRY CONDITIONS ARE EXPECTED ACROSS THE HSA THROUGH
SATURDAY...EXCEPT LAKE EFFECT ACTIVITY TONIGHT INTO FRIDAY
AFTERNOON FOR THE WESTERN ADIRONDACK REGION AND THE WESTERN AND
CENTRAL MOHAWK VALLEY.
A WARM FRONT WILL BRING LIGHT MIXED PRECIPITATION TO THE REGION
SATURDAY NIGHT INTO SUNDAY MORNING WITH TOTAL QPF LESS THAN A
QUARTER OF AN INCH.
MILDER AIR WILL MOVE INTO THE REGION SUNDAY INTO NEXT WEEK WITH
AFTERNOON TEMPERATURES REACHING THE MID 40S TO LOW 50S
SUNDAY...50S AND LOW 60S MONDAY AND 50S TUESDAY...WITH NIGHTTIME
LOWS MAINLY ABOVE FREEZING.
A FRONTAL BOUNDARY COULD BRING A HALF AN INCH TO AN INCH OF
RAINFALL TO THE HSA SUNDAY NIGHT INTO MONDAY...WITH ADDITIONAL
SCATTERED SHOWERS TUESDAY. AT THIS POINT NO HYDRO PROBLEMS ARE
EXPECTED WITH THE RAINFALL AND MINOR SNOW MELT ESPECIALLY OVER THE
SOUTHERN ADIRONDACKS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...LAKE EFFECT SNOW WARNING UNTIL 10 AM EST FRIDAY FOR NYZ032-033.
LAKE EFFECT SNOW ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST
FRIDAY FOR NYZ038.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...WASULA
SHORT TERM...WASULA
LONG TERM...JPV
AVIATION...JPV
HYDROLOGY...WASULA
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
720 PM EST FRI NOV 21 2014
.UPDATE (REST OF TONIGHT AND SATURDAY)...
00Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS SPLIT FLOW ARRIVING ALONG
THE PACIFIC NORTHWEST COAST...WITH ONE BRANCH REMAINING ZONAL IN
NATURE ACROSS THE NORTHERN ROCKIES/NORTHERN PLAINS...WHILE THE OTHER
BRANCH DIVES SOUTHWARD INTO A POTENT AND ENERGETIC SHORTWAVE TROUGH
EJECTING EASTWARD ACROSS THE 4-CORNERS REGION OF THE SOUTHWEST. THE
FLOW DOWNSTREAM OF THIS SHORTWAVE ALONG THE NORTHERN GULF COAST IS
BECOME EVER-MORE RIDGED/ANTI-CYCLONIC IN NATURE IN RESPONSE TO THE
HEIGHT FALLS BEGINS TO SPREAD INTO THE SOUTHERN PLAINS. THE
SHORTWAVE IS PROGGED BY ALL RELIABLE NWP GUIDANCE TO QUICKLY
TRANSLATE EASTWARD TO THE NORTHERN GULF COAST THIS WEEKEND AND ITS
INFLUENCE...OR AT LEAST FRINGE INFLUENCES...WILL BE THE DOMINANT
WEATHER PLAYER IN OUR FORECAST FOR BOTH SATURDAY AND SUNDAY.
SOUTHERN STREAM IS CURRENTLY CUTTING ACROSS THE SOUTHERN GULF AND
SOUTHERN FLORIDA PENINSULA RESULTING IN A WELL DEFINED UPPER LEVEL
MOISTURE GRADIENT ALONG AND JUST NORTH OF THE I4 CORRIDOR THIS
EVENING.
LOWER LEVELS...FLORIDA PENINSULA RESIDES WITHIN A MODERATE EASTERLY
FLOW AROUND THE SOUTHERN PERIPHERY OF STRONG 1035MB CONTINENTAL HIGH
PRESSURE CENTERED OVER VIRGINIA. WEAK ISENTROPIC UPGLIDE BETWEEN THE
295-305K SURFACES OVER THE SOUTHERN HALF OF THE FL PENINSULA IS
PROVIDING ENOUGH LIFT TO SUPPORT THE OVERCAST CANOPY AND SCT LIGHT
SHOWERS/SPRINKLES SEEN ON REGIONAL RADARS TO THE SOUTH OF I-4.
REST OF TONIGHT...GFS/NAM/RAP ALL IN AGREEMENT SHOWING FURTHER
ENHANCEMENT AND NORTHWARD EXPANSION TO THE UPGLIDE REGIME...WITH A
GRADUAL MOISTENING / CONDENSATION PRESSURE DEFICIT REDUCTION TO THE
EFFECTED LAYERS. WITH THIS IN MIND WOULD EXPECT THE OVERCAST
CONDITIONS AND SHOWER CHANCES TO ALSO INCREASE AND SPREAD NORTHWARD
WITH TIME. ANY SHOWERS WILL STILL LIKELY BE VERY LIGHT AND NOT
ANTICIPATING MUCH RAINFALL ACCUMULATION...BUT POTENTIALLY ENOUGH TO
DAMPEN SOME OUTDOOR ACTIVITIES...ESPECIALLY SOUTH OF TAMPA BAY.
TEMPERATURES WILL ONLY SLOWLY FALL DURING THE OVERNIGHT...AND DO NOT
EXPECT MUCH OF A SWING BETWEEN NOW AND SUNRISE IN MOST LOCATIONS.
SATURDAY...
UPPER LEVEL ENERGY WILL BEGIN TO EJECT OUT OVER THE GULF OF MEXICO
THROUGH THE DAY. A SURFACE REFLECTION WARM FRONTAL FEATURE IS
EXPECTED TO ORGANIZE AND EXTEND EASTWARD TO THE SOUTHERN
PENINSULA...AND THEN BEGIN LIFTING SLOWLY NORTHWARD THROUGH THE DAY.
LATEST GUIDANCE RUNS ARE BECOMING SLOWER WITH THE NORTHWARD
ADVANCEMENT OF THIS WARM FRONT...AND THE FIRST DAY OF THE WEEKEND IS
LOOKING MORE CLOUDY AND SHOWERY FOR THE MAJORITY OF THE AREA WITH
TIME. STEADY AND PERSISTENT UPGLIDE AND A MOIST LOWER 10-15KFT OF
THE ATMOSPHERE SHOULD SUPPORT OFF AND ON LIGHT SHOWERS. THE
POTENTIAL FOR SOME HEAVIER SHOWERS SHOULD BEGIN SATURDAY AFTERNOON
ACROSS THE SOUTHERN HALF OF THE AREA THROUGH A COMBINATION OF
UPGLIDE AND A FEW HUNDRED J/KG OF MIXED LAYER CAPE. HOWEVER...THE
SLOWER FRONTAL ADVANCEMENT MAY KNOCK SOME OF THIS POTENTIAL LOWER
LEVEL CAPE DOWN IN FUTURE MODEL RUNS. EITHER WAY...SHOWALTER INDICES
ARE AROUND ZERO FOR MUCH OF THE AREA SATURDAY AFTERNOON...
INDICATING AT LEAST SOME POTENTIAL FOR ELEVATED
INSTABILITY/CONVECTION. HAVE EXPANDED THE AREA OF ISOLATED THUNDER
IN THE GRIDS NORTHWARD INTO THE NATURE COAST TO COINCIDE WITH THESE
SHOWALTER INDICES. CURRENT HIGH TEMPERATURE GRID IS LIKELY MORE
REPRESENTATIVE OF THE EARLIER FRONTAL PASSAGE FOR THE SOUTHERN ZONES
EXPECTED WITH PREVIOUS MODEL RUNS. IF THE SLOWER TREND ENDS UP
VERIFYING...THEN LOWER 80S SOUTH OF TAMPA BAY...MAY BE A BIT
OPTIMISTIC. WILL NOT MAKE TO MANY SIGNIFICANT CHANGES FOR NOW AND
ALLOW THE OVERNIGHT SHIFT TO EVALUATE IF THE SLOWER TREND AND HENCE
COOLER TEMPERATURES STILL LOOK VALID.
&&
.LONG TERM /SATURDAY NIGHT-FRIDAY/...
MODEL SOLUTIONS ARE IN FAIRLY GOOD AGREEMENT THROUGH THE LONG TERM
PERIOD. DURING SATURDAY NIGHT AND SUNDAY A MID/UPPER LEVEL TROUGH
WILL BE MOVING ACROSS THE LOWER MISSISSIPPI VALLEY AND INTO THE
TENNESSEE AND OHIO VALLEYS WITH SOME SHORTWAVE ENERGY TRAILING SOUTH
INTO THE GULF OF MEXICO. THIS WILL DRIVE THE DEVELOPING WARM FRONT
NORTHWARD THROUGH THE REGION SATURDAY NIGHT...WHILE A WEAKENING COLD
FRONT MOVES INTO THE SOUTHEAST STATES. THE WARM FRONT WILL THEN
REMAIN JUST NORTH OF THE FORECAST AREA ON SUNDAY. THE BEST RAIN
CHANCES WILL REMAIN OVER THE NATURE COAST WHERE THE DEEPEST MOISTURE
AND BEST FORCING FOR ASCENT WILL RESIDE. QUITE A WARM AND MOIST
AIRMASS WILL BE MOVING INTO THE REGION SATURDAY NIGHT AND
SUNDAY...SO WILL MENTION BOTH SHOWERS AND THUNDERSTORMS IN THE
FORECAST. ADDITIONALLY...THE STORM PREDICTION CENTER HAS NATURE
COAST LOCATIONS OUTLOOKED FOR A SLIGHT RISK OF SEVERE THUNDERSTORMS
SATURDAY NIGHT AND SUNDAY. AT THIS POINT IT APPEARS THAT THE MAIN
THREAT WILL BE ISOLATED TORNADOES AND DAMAGING WINDS SATURDAY NIGHT
AND THEN DAMAGING WIND POTENTIAL ON SUNDAY.
EARLY NEXT WEEK A DEEPENING TROUGH WILL DEVELOP OVER THE CENTRAL
U.S. AND MOVE EASTWARD INTO THE EASTERN STATES DURING MIDWEEK.
THIS WILL HELP TO DRIVE THE COLD FRONT OVER THE SOUTHEAST STATES
INTO THE REGION DURING TUESDAY AND EXITING THE AREA BY WEDNESDAY.
FOR MONDAY AND MONDAY NIGHT SOUTH TO SOUTHWEST WINDS WILL CONTINUE
TO BRING MOISTURE NORTHWARD WITH A CHANCE OF SHOWERS AND
THUNDERSTORMS...ESPECIALLY ACROSS THE NATURE COAST CLOSEST TO THE
SLOW MOVING COLD FRONT/TROUGH. DURING TUESDAY AND TUESDAY NIGHT THE
FRONT WILL MOVE SOUTHWARD THROUGH THE REGION AND WITH PLENTY OF
MOISTURE IN PLACE WE SHOULD SEE SCATTERED TO NUMEROUS SHOWERS AND A
FEW THUNDERSTORMS. A FEW SHOWERS MAY LINGER WEDNESDAY AS THE
MID/UPPER LEVEL TROUGH AXIS SWINGS ACROSS AREA...OTHERWISE SOME
COOLER AND DRIER AIR WILL RETURN.
TEMPERATURES THROUGH MONDAY NIGHT WILL GENERALLY BE ABOVE NORMAL
WITH DAYTIME HIGHS CLIMBING INTO THE UPPER 70S TO MID 80S AND LOWS
IN THE 60S TO LOWER 70S. ALONG WITH THE ABOVE NORMAL TEMPERATURES
WILL COME INCREASED HUMIDITY WITH DEW POINTS CLIMBING BACK INTO THE
60S AND LOWER 70S. FOR TUESDAY AND TUESDAY TEMPERATURES WILL BE NEAR
TO A FEW DEGREES BELOW NORMAL WITH HIGHS IN THE UPPER 60S TO NEAR 80
DEGREES AND LOWS IN THE UPPER 40S TO AROUND 60. FOR WEDNESDAY
THROUGH FRIDAY EXPECT BELOW NORMAL TEMPERATURES TO RETURN WITH
HIGHS MAINLY IN THE 60S AND LOWS MOSTLY IN THE 40S.
&&
.AVIATION...
SKIES ARE NOW OVERCAST ACROSS WEST-CENTRAL AND SOUTHWEST FLORIDA AND
WILL REMAIN SO FOR THE BULK OF THE TAF PERIOD. CEILINGS ARE STILL
ABOVE VFR CONDITIONS FOR ALL TERMINALS BUT WILL BE LOWERING THROUGH
THE OVERNIGHT HOURS...ALONG WITH SCT LIGHT SHOWERS AND SPRINKLES.
THE RAINFALL SHOULD NOT BE HEAVY ENOUGH FOR ANY VISIBILITY
RESTRICTIONS. LATE TONIGHT AND INTO THE DAY ON SATURDAY...A WARM
FRONT WILL LIFT INTO THE REGION PROVIDING GOOD CHANCES FOR PERIODS
OF MVFR CEILINGS FOR ALL TERMINAL. SHOWER COVERAGE IS ALSO LIKELY TO
INCREASE THROUGH THE DAY WITH BETTER CHANCES FOR A FEW HEAVY
DOWNPOURS BY THE AFTERNOON HOURS.
&&
.MARINE...
A TIGHT PRESSURE GRADIENT BETWEEN STRONG SURFACE HIGH PRESSURE TO
THE NORTH AND A STALLED FRONTAL BOUNDARY OVER SOUTHERN FLORIDA
CONTINUES TO PRODUCE GUSTY EAST NORTHEAST WINDS ACROSS THE COASTAL
WATERS. CONDITIONS WILL REACH SMALL CRAFT ADVISORY LEVEL OVER THE
OUTER WATERS. WINDS WILL REMAIN GUSTY WITH SMALL CRAFT EXERCISE
CAUTION CONDITIONS ACROSS ALL COASTAL WATERS THROUGH THE WEEKEND.
THE WINDS WILL VEER TO THE SOUTH SOUTHEAST AND RAIN CHANCES WILL
INCREASE ON SATURDAY AND SUNDAY AS AN AREA OF LOW PRESSURE MOVES
NORTH OF THE AREA. THE COLD FRONT ASSOCIATED WITH THIS LOW IS
EXPECTED TO MOVE THROUGH THE COASTAL WATERS LATE MONDAY INTO
TUESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 62 79 68 81 / 30 40 50 30
FMY 65 82 70 85 / 40 40 30 30
GIF 62 77 67 83 / 30 40 50 40
SRQ 62 82 70 83 / 30 40 40 30
BKV 57 77 70 82 / 20 40 60 50
SPG 63 78 69 81 / 30 40 50 30
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...SMALL CRAFT ADVISORY UNTIL 1 AM EST SATURDAY FOR
BONITA BEACH TO ENGLEWOOD OUT 20 TO 60 NM-ENGLEWOOD TO
TARPON SPRINGS OUT 20 TO 60 NM-TARPON SPRINGS TO
SUWANNEE RIVER OUT 20 TO 60 NM.
&&
$$
UPDATE/AVIATION...MROCZKA
LONG TERM/DECISION SUPPORT SERVICES...21/JELSEMA
MARINE...11/MCKAUGHAN
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
926 PM CST FRI NOV 21 2014
.UPDATE...
746 PM CST
MINOR CHANGES TO THE GOING FORECAST THIS EVENING...MAINLY SLOWING
TIMING OF PRECIP INTO THE REGION. DEWPOINTS REMAIN PRETTY DRY
ACROSS THE REGION WITH SINGLE DIGITS STILL IN PLACE NORTH OF I-80
AND LOW/MID TEENS TO THE SOUTH. REGIONAL RADAR MOSAIC SHOWS
SCATTERED SHOWERS MOVING ACROSS NE MO/SE IA INTO WEST CENTRAL IL
THIS EVENING AND SHOULD START TO OVERSPREAD OUR SOUTHWESTERN
COUNTIES BY AROUND 04Z OR SO...AND INTO THE CHICAGO AREA CLOSER TO
THE 06-07Z HOUR. LOWERED POPS A LITTLE MAINLY DUE TO LIMITED
COVERAGE NOTED UPSTREAM. WHILE TEMPERATURES HAVE SOME DOWNWARD
POTENTIAL FROM WET BULBING THIS EVENING...CLOUDS HAVE STARTED TO
MOVE OVERHEAD WITH A FEW SITES SHOWING TEMPS REBOUNDING A DEGREE
OR TWO...WITH MID/UPPER 30S NOT TOO FAR AWAY. LATEST RAP GUIDANCE
ACTUALLY HAS AIR TEMPERATURES RISING ABOVE FREEZING AROUND THE
ONSET OF PRECIP...SO IT APPEARS THE WINDOW OF POTENTIAL FREEZING
RAIN WILL REMAIN FAIRLY SHORT. WILL MAINTAIN CURRENT ADVISORY
TIMING AS EVEN A LIGHT GLAZE OF ICE CAN BE HAZARDOUS...BUT IF
ANYTHING WE MAY BE ABLE TO LET IT GO A LITTLE EARLY.
BMD
&&
.SHORT TERM...
352 PM CST
THROUGH TONIGHT...
CONDITIONS WILL REMAIN QUIET FOR THE REMAINDER OF THE AFTERNOON
UNDER MOSTLY CLEAR SKIES. LATEST SATELLITE IMAGERY SHOWS A DENSE
MASS OF CLOUD COVER ASSOCIATED WITH A SURGE OF MOISTURE CROSSING THE
MISSOURI VALLEY AND APPROACHING WRN IL. AT THE SURFACE...LATEST OBS
INDICATE DEWPOINTS RAPIDLY INCREASING INTO THE 40S AND 50S WITH THE
MOISTURE SURGE...WHILE DEWPOINTS OVER NRN IL/NWRN IN UNDER THE
MOSTLY CLEAR SKIES REMAIN IN THE SINGLE DIGITS TO THE LOWER TEENS.
THE PCPN SHIELD ASSOCIATED WITH THE APPROACHING SYSTEM WILL TAKE A
LITTLE TIME TO OVERCOME THE VERY DRY AIR IN PLACE...BUT UPSTREAM
TRENDS AND THE SHORT TERM MODEL GUIDANCE ALIGN WELL WITH THE TREND
TO BRING INCREASING POPS INTO THE FAR SWRN PORTIONS OF THE CWA AFTER
SUNSET AND THEN QUICKLY SPREADING TO THE NORTH AND EAST THROUGH THE
EVENING AND OVERNIGHT. THERE WILL BE A SLOW INCREASE IN SFC TEMPS
THROUGH THE NIGHT UNDER STRONG WARM ADVECTION DRIVEN BY A SWLY LOW
LEVEL JET TO 45KT. AVAILABLE DEEP LAYER MOISTURE WITH SYSTEM IS
LIMITED...SO ACTUAL QPF AMOUNTS EXPECTED SHOULD BE RELATIVELY
LIGHT. WILL MAINTAIN AND MAKE NO CHANGES TO THE GOING FREEZING RAIN
ADVISORY. WITH LIGHT QPF AMOUNTS EXPECTED...ANY ICE ACCUMULATION
SHOULD RANGE FROM A LIGHT GLAZING TO A LITTLE OVER A TENTH OF AN
INCH. THERE IS ALSO A CHANCE FOR SOME GLAZING AS EARLY AS 23Z-00Z
OVER THE PONTIAC AREA...WITH SOME LIGHT DRIZZLE OR LIGHT RAIN COMING
IN CONTACT WITH ROAD SURFACES AND WALKWAYS THAT ARE CURRENTLY BELOW
FREEZING DUE TO THE RECENT UNSEASONABLY COLD WEATHER. THROUGH THE
LATE EVENING AND INTO THE OVERNIGHT HOURS...THE FREEZING PCPN WILL
GRADUALLY CHANGE OVER TO A MIX OF FREEZING OR LIQUID TO ALL LIQUID
PCPN AS THE WARMER AIR SURGES INTO THE REGION LATE THIS EVENING AND
OVERNIGHT TONIGHT. THE FREEZING PCPN POTENTIAL SHOULD DIMINISH FROM
SOUTHWEST TO NORTHEAST AS THE WARMER AIR OVERSPREAD THE
REGION...WITH THE FREEZING PCPN POTENTIAL ENDING OVER THE FAR NERN
PORTIONS OF THE CWA...INCLUDING THE FAR NORTHERN PORTIONS OF THE
CHICAGO AREA BY DAYBREAK SATURDAY MORNING.
KREIN
&&
.LONG TERM...
352 PM CST
SATURDAY THROUGH FRIDAY...
FOR THE REMAINDER OF THE DAY ON SATURDAY...WITH LOW PRESSURE
DEEPENING OVER THE NRN PLAINS WHILE HIGH PRESSURE MOVES OFF THE
SOUTH EAST ATLANTIC COAST...THE PERSISTENT FETCH OF WARM...MOIST AIR
WILL CONTINUE TO STREAM OVER THE AREA...WITH LIGHT RAIN PERSISTING
THROUGH THE DAY. TEMPERATURES WILL CONTINUE TO INCREASE THROUGH THE
DAY ON SATURDAY WITH HIGHS RANGING FROM AROUND 50F OVER THE PONTIAC
AREA TO THE MIDDLE 40S OVER THE REMAINDER OF THE CWA. DEWPOINTS ARE
ALSO EXPECTED TO CONTINUE TO RISE THROUGH SATURDAY...REACHING INTO
THE MIDDLE 40S...WHICH WILL BE A STARK CONTRAST TO THE UNSEASONABLY
COLD...DRY AIR THAT HAS BEEN THE PREVAILING CONDITION FOR THE PAST
SEVERAL DAYS. WITH THE MAIN FOCUSING MECHANISM TO MAINTAIN THE PCPN
BEING WIDESPREAD...BUT GRADUAL...ISENTROPIC LIFT...RAINFALL AMOUNTS
WILL CONTINUE TO BE RELATIVELY LIGHT THROUGH SATURDAY NIGHT...WITH
WIDESPREAD AMOUNTS OF A COUPLE TENTHS OF AN INCH.
MORE SIGNIFICANT RAINFALL IS SETTING UP FOR SUNDAY AND INTO SUNDAY
NIGHT AS A STRONG SRN STREAM SHORTWAVE LIFTS OUT OF THE SOUTH HIGH
PLAINS PHASES WITH ANOTHER SHORTWAVE LIFTING FROM THE SOUTHWEST GULF
COAST REGION. THESE SYSTEM WILL RESULT IN A DEEPENING SFC LOW OVER
SRN IL BY SUNDAY EVENING AS A NRN STREAM SHORTWAVE TRACKS ACROSS THE
NRN PLAINS TO THE WRN GREAT LAKE REGION. THE SRN STREAM SYSTEM WILL
BE THE PRIMARY FOCUS FOR HEAVIER RAIN. THE MODELS CONTINUE TO
INDICATE ALMOST UNPRECEDENTED LEVELS OF DEEP LAYER MOISTURE FOR LATE
NOVEMBER...WITH PWATS INCREASING TO IN EXCESS OF 1 INCH THROUGH THE
DAY ON SUNDAY. WHILE ANY THUNDER REMAINS UNLIKELY DUE TO A LACK OF
INSOLATION UNDER PERSISTENT CLOUD COVER...THE UNUSUALLY HIGH
MOISTURE CONTENT SHOULD BRING AREAS OF FOG THROUGH SUNDAY AS WELL AS
SOME LOCALLY HEAVY RAINFALL. WIDESPREAD RAINFALL OF 1 TO 1.5 INCHES
IS POSSIBLE FOR SUNDAY THROUGH SUNDAY NIGHT WITH LOCALIZED AREAS OF
EVEN HEAVIER RAIN POSSIBLE IS SOME CONVECTIVE ELEMENTS CAN DEVELOP.
CONDITIONS WILL REMAIN MUCH WARMER/MOISTER THAN RECENT DAYS THROUGH
SUNDAY WITH HIGHS ONCE AGAIN EXPECTED TO BE IN THE UPPER 40S TO
AROUND 50F.
THE MODELS HAVE SETTLED INTO A RELATIVELY CONSISTENT SOLUTION OF
PHASING THE NRN AND SRN STREAM SHORTWAVES OVER THE ERN GREAT LAKES
BY MONDAY MORNING WITH A SFC LOW ARND 980MB DEVELOPING. AS THE LOW
DEEPENS FURTHER ON MONDAY...STRONG WEST WINDS WILL DEVELOP OVER THE
AREA WITH WINDS INCREASING TO ARND 25 MPH WITH 35MPH GUSTS.
CONSIDERING A POSSIBILITY THAT THE MODELS COULD EVEN BE UNDER
FORECASTING THE POTENTIAL DEEPENING OF THIS LOW...WHICH IS A
POSSIBILITY GIVEN THE LATE FALL CONTRAST OF WARM...MOIST GULF AIR
ASSOCIATED WITH THE SRN STREAM SYSTEM AND MUCH COLDER AIR WITH THE
NRN STREAM SYSTEM...THERE IS THE CHANCE THAT WIND ADVISORY CRITERIA
WINDS OF SUSTAINED 30 MPH WINDS WITH 45 MPH GUSTS MAY OCCUR ON
MONDAY.
THE DEEP SFC LOW IS EXPECTED TO LIFT OUT TO THE NORTHEAST MONDAY
NIGHT AND TUESDAY...WEAK HIGH PRESSURE WILL BUILD ACROSS THE PLAINS
AS THE SFC WHILE BROAD UPPER TROUGHING DEVELOPS OVER THE CNTRL
CONUS. THE UPPER LEVEL PATTERN IS EXPECTED TO BECOME MORE
AMPLIFIED...BUT SLOWLY PROGRESSIVE BY MIDWEEK THROUGH THE END OF NEXT
WEEK...THE AREA REMAINING UNDER PERSISTENT NWLY FLOW AND COLD
ADVECTION ALOFT. SO THE WEEKEND WARMUP SHOULD COME TO AN ABRUPT END
BY MONDAY AS A STRONG COLD FRONT PASSES THROUGH THE REGION AND
TEMPERATURES DROP BACK INTO THE UPPER 30S TO ARND 40F ON MONDAY WITH
HIGHS ONLY IN THE UPPER 20S TO LOWER 30S FOR TUESDAY. THROUGH THE
REMAINDER OF NEXT WEEK...THE TEMPERATURE TREND WILL GO BACK TO WELL
BELOW NORMAL...WITH HIGHS ON THANKSGIVING ONLY IN THE LOWER TO
MIDDLE 20S. A WEAK CLIPPER-TYPE SYSTEM DROPPING OUT OF THE NRN
ROCKIES ON TUESDAY IS EXPECTED TO DIVE INTO THE LOWER MISSISSIPPI
VALLEY BY WEDNESDAY AS ANOTHER WEAK SHORTWAVE DROPS THROUGH THE
UPPER GREAT LAKES. THIS COULD BRING SOME LIGHT SNOW FOR
WEDNESDAY...BUT THEN STRONG HIGH PRESSURE SHOULD BUILD ACROSS THE
MIDDLE MISSISSIPPI VALLEY THROUGH THE GREAT LAKES. THIS COULD SET
UP A WEAK PRESSURE GRADIENT PATTERN OVER THE REGION...BRINGING THE
POSSIBILITY FOR A LAKE EFFECT PLUME TO DEVELOP OVER LAKE MICHIGAN.
WHILE IT IS STILL WAY TOO EARLY TO CONSIDER THE FINER DETAILS OF
LAKE EFFECT SNOW ASSOCIATED WITH MESOSCALE BANDING OF A LAKE
PLUME...THE PATTERN WOULD BE CONDUCIVE FOR SUCH TYPE OF DEVELOPMENT.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* ISOLATED-SCATTERED FREEZING RAIN SHOWERS ARRIVE AROUND 06Z. DRY
AIR MAY LIMIT ACTIVITY TO FREEZING SPRINKLES INITIALLY.
* TEMPS EXPECTED TO RISE ABOVE FREEZING OVERNIGHT.
* CIGS LOWER TO MVFR INTO THE OVERNIGHT WITH A GOOD CHANCE FOR IFR
SATURDAY MORNING.
* LOW LEVEL WIND SHEAR POSSIBLE TONIGHT WITH WINDS INCREASING TO
45 KT AROUND 2000 FT AGL.
* LIQUID RAIN SHOWERS LINGER SATURDAY MORNING WITH DRIZZLE
POSSIBLE THROUGH THE DAY.
MDB
//DISCUSSION...UPDATED 03Z...
HAVE ADJUSTED TAFS TO REFLECT A LOWER COVERAGE OF PRECIPITATION
BASED ON LATEST TRENDS. RADAR MOSAIC SHOWS SCATTERED PRECIP MOVING
NORTHEASTWARD INTO NORTHERN ILLINOIS WITH ONE MORE FOCUSED AREA
AIMING TOWARDS THE PNT TO GYY CORRIDOR AND ANOTHER LESSOR
COVERAGE AREA AIMING TOWARDS AREAS FROM SQI TO UGN. DO NOT SEE
MUCH EXPANSION IN OVERALL COVERAGE FROM WHAT IS OUT THERE NOW SO
HAVE CARRIED PREVAILING VCSH WITH TEMPO -FZRA. AIR TEMPS ARE
WARMING UP BUT GROUND TEMPS ARE LIKELY BELOW FREEZING SO EVEN IF
AIR TEMPS WARM ABOVE FREEZING GLAZING MAY BE POSSIBLE THROUGH
DAYBREAK FOR TERMINALS THAT SEE RAINFALL. TEMPS MAY COOL A FEW
DEGREES WHERE RAIN FALLS GIVEN THE VERY DRY LOW LEVEL AIRMASS
CURRENTLY IN PLACE.
FROM 00Z...
FREEZING RAIN SHOWERS ARE EXPECTED TO ARRIVE TOWARD 06Z BUT VERY
DRY AIR IN THE LOW LEVELS MAY LIMIT HOW MUCH ACTUALLY REACHES THE
GROUND INITIALLY. MUCH OF THE EARLY ACTIVITY MAY FALL AS
SPRINKLES. DO EXPECT THAT COVERAGE WILL INCREASE OVERNIGHT WITH
MOISTENING ALLOWING FREEZING RAIN TO OCCUR AT THE SURFACE AT THE
TERMINALS. SURFACE AIR TEMPS WILL BE WARMING OVERNIGHT AND LATEST
TRENDS SUPPORT A RISE ABOVE FREEZING BY 12Z OR SO. SHOWERS WILL
LIKELY LINGER BEYOND 12Z AND BE POSSIBLE THROUGH MIDDAY OR EVEN
MUCH OF THE AFTERNOON...WITH DRIZZLE POSSIBLE AS WELL.
CIGS WILL LOWER THROUGH THE NIGHT WITH MVFR EXPECTED EARLY
TONIGHT. FURTHER LOWERING TO IFR IS EXPECTED SATURDAY MORNING AND
THERE ARE MIXED SIGNALS ON WHETHER IT WILL IMPROVE TO MVFR GOING
INTO THE AFTERNOON OR NOT. IF DRIZZLE CAN BE MORE PERSISTENT THEN
IFR MAY REMAIN THROUGH THE AFTERNOON. CONDITIONS MAY LOWER WITH
FOG DEVELOPING SATURDAY EVENING BEFORE WIDESPREAD RAIN ARRIVES
LATE SUNDAY NIGHT. SOUTH WINDS WILL INCREASE SLIGHTLY INTO THE
OVERNIGHT WHILE WINDS ABOVE THE SURFACE NEAR 2000 FT INCREASE TO
45 KT LEADING TO DECENT LOW LEVEL WIND SHEAR POTENTIAL THROUGH
DAYBREAK.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH CONFIDENCE IN FREEZING RAIN SHOWERS ARRIVING AFTER ABOUT
06Z...BUT COVERAGE MAY STAY RATHER ISOLATED/SCATTERED.
* HIGH CONFIDENCE IN TEMPS WARMING ABOVE FREEZING OVERNIGHT.
* HIGH CONFIDENCE IN CIGS LOWERING TO MVFR TONIGHT. MEDIUM
CONFIDENCE IN A PERIOD OF IFR SATURDAY MORNING...LOW CONFIDENCE
IN DURATION.
* HIGH CONFIDENCE IN 45 KT WINDS AT 2000 FT AGL TONIGHT.
* MEDIUM CONFIDENCE IN INTERMITTENT RAIN SHOWERS/DRIZZLE SATURDAY.
MDB
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY...RAIN. HEAVY AT TIMES. IFR LIKELY. GUSTY S TO SE WINDS.
MONDAY...CHANCE -RASN EARLY AND -SN LATER. MVFR CIGS POSSIBLE.
GUSTY W TO SW WINDS.
TUESDAY...CHANCE OF FLURRIES. MVFR CIGS PSBL. BREEZY WEST WINDS.
WEDNESDAY...LIGHT SNOW POSSIBLE. MVFR CIGS/VIS POSSIBLE. WEST TO
SOUTHWEST WINDS 10 KT OR LESS.
THANKSGIVING DAY...VFR LIKELY.
MDB
&&
.MARINE...
242 PM...HIGH PRESSURE OVER THE SOUTHERN LAKES AND OHIO VALLEY
WILL MOVE SOUTHEAST TONIGHT REACHING THE CAROLINA COAST ON
SATURDAY AS LOW PRESSURE MOVES ACROSS NORTHERN ONTARIO AND JAMES
BAY TONIGHT. THE GRADIENT BETWEEN THESE TWO SYSTEMS WILL STEADILY
INCREASE OVER LAKE MICHIGAN TONIGHT WITH GALE FORCE WINDS
EXPECTED...POSSIBLY GUSTING AS HIGH AS 45KTS ACROSS THE NORTHERN
PORTION OF THE LAKE. THE GRADIENT WILL BEGIN TO WEAKEN LATER
SATURDAY AFTERNOON INTO SATURDAY EVENING...BUT ANOTHER LOW MOVING
ACROSS THE NORTHERN PLAINS SATURDAY NIGHT INTO SUNDAY WILL TIGHTEN
THE SOUTHERLY GRADIENT AGAIN. THIS LOW WILL BEGIN TO WEAKEN SUNDAY
EVENING AND THEN BE ABSORBED BY ANOTHER STRONGER LOW WHICH WILL
DEVELOP OVER THE SOUTHERN PLAINS SATURDAY NIGHT INTO SUNDAY...THEN
MOVE NORTH ACROSS LAKE MICHIGAN SUNDAY NIGHT INTO MONDAY MORNING.
THIS LOW HAS BEEN FORECAST TO DEEPEN TO AS LOW AS 975MB NEAR LAKE
SUPERIOR FOR SEVERAL DAYS. IF THIS OCCURS...WESTERLY HIGH END
GALES TO 45 KTS WOULD LIKELY DEVELOP MONDAY WITH THE POTENTIAL FOR
SOME STORM FORCE WINDS OR GUSTS. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FREEZING RAIN ADVISORY...ILZ019-ILZ021-ILZ023-ILZ032-ILZ033-
ILZ039 UNTIL 6 AM SATURDAY.
FREEZING RAIN ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-
ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ020-ILZ022 UNTIL 9 AM
SATURDAY.
IN...FREEZING RAIN ADVISORY...INZ001-INZ002 UNTIL 9 AM SATURDAY.
FREEZING RAIN ADVISORY...INZ010-INZ011-INZ019 UNTIL 6 AM
SATURDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM SATURDAY.
SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 3 PM SATURDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
752 PM CST FRI NOV 21 2014
.UPDATE...
746 PM CST
MINOR CHANGES TO THE GOING FORECAST THIS EVENING...MAINLY SLOWING
TIMING OF PRECIP INTO THE REGION. DEWPOINTS REMAIN PRETTY DRY
ACROSS THE REGION WITH SINGLE DIGITS STILL IN PLACE NORTH OF I-80
AND LOW/MID TEENS TO THE SOUTH. REGIONAL RADAR MOSAIC SHOWS
SCATTERED SHOWERS MOVING ACROSS NE MO/SE IA INTO WEST CENTRAL IL
THIS EVENING AND SHOULD START TO OVERSPREAD OUR SOUTHWESTERN
COUNTIES BY AROUND 04Z OR SO...AND INTO THE CHICAGO AREA CLOSER TO
THE 06-07Z HOUR. LOWERED POPS A LITTLE MAINLY DUE TO LIMITED
COVERAGE NOTED UPSTREAM. WHILE TEMPERATURES HAVE SOME DOWNWARD
POTENTIAL FROM WET BULBING THIS EVENING...CLOUDS HAVE STARTED TO
MOVE OVERHEAD WITH A FEW SITES SHOWING TEMPS REBOUNDING A DEGREE
OR TWO...WITH MID/UPPER 30S NOT TOO FAR AWAY. LATEST RAP GUIDANCE
ACTUALLY HAS AIR TEMPERATURES RISING ABOVE FREEZING AROUND THE
ONSET OF PRECIP...SO IT APPEARS THE WINDOW OF POTENTIAL FREEZING
RAIN WILL REMAIN FAIRLY SHORT. WILL MAINTAIN CURRENT ADVISORY
TIMING AS EVEN A LIGHT GLAZE OF ICE CAN BE HAZARDOUS...BUT IF
ANYTHING WE MAY BE ABLE TO LET IT GO A LITTLE EARLY.
BMD
&&
.SHORT TERM...
352 PM CST
THROUGH TONIGHT...
CONDITIONS WILL REMAIN QUIET FOR THE REMAINDER OF THE AFTERNOON
UNDER MOSTLY CLEAR SKIES. LATEST SATELLITE IMAGERY SHOWS A DENSE
MASS OF CLOUD COVER ASSOCIATED WITH A SURGE OF MOISTURE CROSSING THE
MISSOURI VALLEY AND APPROACHING WRN IL. AT THE SURFACE...LATEST OBS
INDICATE DEWPOINTS RAPIDLY INCREASING INTO THE 40S AND 50S WITH THE
MOISTURE SURGE...WHILE DEWPOINTS OVER NRN IL/NWRN IN UNDER THE
MOSTLY CLEAR SKIES REMAIN IN THE SINGLE DIGITS TO THE LOWER TEENS.
THE PCPN SHIELD ASSOCIATED WITH THE APPROACHING SYSTEM WILL TAKE A
LITTLE TIME TO OVERCOME THE VERY DRY AIR IN PLACE...BUT UPSTREAM
TRENDS AND THE SHORT TERM MODEL GUIDANCE ALIGN WELL WITH THE TREND
TO BRING INCREASING POPS INTO THE FAR SWRN PORTIONS OF THE CWA AFTER
SUNSET AND THEN QUICKLY SPREADING TO THE NORTH AND EAST THROUGH THE
EVENING AND OVERNIGHT. THERE WILL BE A SLOW INCREASE IN SFC TEMPS
THROUGH THE NIGHT UNDER STRONG WARM ADVECTION DRIVEN BY A SWLY LOW
LEVEL JET TO 45KT. AVAILABLE DEEP LAYER MOISTURE WITH SYSTEM IS
LIMITED...SO ACTUAL QPF AMOUNTS EXPECTED SHOULD BE RELATIVELY
LIGHT. WILL MAINTAIN AND MAKE NO CHANGES TO THE GOING FREEZING RAIN
ADVISORY. WITH LIGHT QPF AMOUNTS EXPECTED...ANY ICE ACCUMULATION
SHOULD RANGE FROM A LIGHT GLAZING TO A LITTLE OVER A TENTH OF AN
INCH. THERE IS ALSO A CHANCE FOR SOME GLAZING AS EARLY AS 23Z-00Z
OVER THE PONTIAC AREA...WITH SOME LIGHT DRIZZLE OR LIGHT RAIN COMING
IN CONTACT WITH ROAD SURFACES AND WALKWAYS THAT ARE CURRENTLY BELOW
FREEZING DUE TO THE RECENT UNSEASONABLY COLD WEATHER. THROUGH THE
LATE EVENING AND INTO THE OVERNIGHT HOURS...THE FREEZING PCPN WILL
GRADUALLY CHANGE OVER TO A MIX OF FREEZING OR LIQUID TO ALL LIQUID
PCPN AS THE WARMER AIR SURGES INTO THE REGION LATE THIS EVENING AND
OVERNIGHT TONIGHT. THE FREEZING PCPN POTENTIAL SHOULD DIMINISH FROM
SOUTHWEST TO NORTHEAST AS THE WARMER AIR OVERSPREAD THE
REGION...WITH THE FREEZING PCPN POTENTIAL ENDING OVER THE FAR NERN
PORTIONS OF THE CWA...INCLUDING THE FAR NORTHERN PORTIONS OF THE
CHICAGO AREA BY DAYBREAK SATURDAY MORNING.
KREIN
&&
.LONG TERM...
352 PM CST
SATURDAY THROUGH FRIDAY...
FOR THE REMAINDER OF THE DAY ON SATURDAY...WITH LOW PRESSURE
DEEPENING OVER THE NRN PLAINS WHILE HIGH PRESSURE MOVES OFF THE
SOUTH EAST ATLANTIC COAST...THE PERSISTENT FETCH OF WARM...MOIST AIR
WILL CONTINUE TO STREAM OVER THE AREA...WITH LIGHT RAIN PERSISTING
THROUGH THE DAY. TEMPERATURES WILL CONTINUE TO INCREASE THROUGH THE
DAY ON SATURDAY WITH HIGHS RANGING FROM AROUND 50F OVER THE PONTIAC
AREA TO THE MIDDLE 40S OVER THE REMAINDER OF THE CWA. DEWPOINTS ARE
ALSO EXPECTED TO CONTINUE TO RISE THROUGH SATURDAY...REACHING INTO
THE MIDDLE 40S...WHICH WILL BE A STARK CONTRAST TO THE UNSEASONABLY
COLD...DRY AIR THAT HAS BEEN THE PREVAILING CONDITION FOR THE PAST
SEVERAL DAYS. WITH THE MAIN FOCUSING MECHANISM TO MAINTAIN THE PCPN
BEING WIDESPREAD...BUT GRADUAL...ISENTROPIC LIFT...RAINFALL AMOUNTS
WILL CONTINUE TO BE RELATIVELY LIGHT THROUGH SATURDAY NIGHT...WITH
WIDESPREAD AMOUNTS OF A COUPLE TENTHS OF AN INCH.
MORE SIGNIFICANT RAINFALL IS SETTING UP FOR SUNDAY AND INTO SUNDAY
NIGHT AS A STRONG SRN STREAM SHORTWAVE LIFTS OUT OF THE SOUTH HIGH
PLAINS PHASES WITH ANOTHER SHORTWAVE LIFTING FROM THE SOUTHWEST GULF
COAST REGION. THESE SYSTEM WILL RESULT IN A DEEPENING SFC LOW OVER
SRN IL BY SUNDAY EVENING AS A NRN STREAM SHORTWAVE TRACKS ACROSS THE
NRN PLAINS TO THE WRN GREAT LAKE REGION. THE SRN STREAM SYSTEM WILL
BE THE PRIMARY FOCUS FOR HEAVIER RAIN. THE MODELS CONTINUE TO
INDICATE ALMOST UNPRECEDENTED LEVELS OF DEEP LAYER MOISTURE FOR LATE
NOVEMBER...WITH PWATS INCREASING TO IN EXCESS OF 1 INCH THROUGH THE
DAY ON SUNDAY. WHILE ANY THUNDER REMAINS UNLIKELY DUE TO A LACK OF
INSOLATION UNDER PERSISTENT CLOUD COVER...THE UNUSUALLY HIGH
MOISTURE CONTENT SHOULD BRING AREAS OF FOG THROUGH SUNDAY AS WELL AS
SOME LOCALLY HEAVY RAINFALL. WIDESPREAD RAINFALL OF 1 TO 1.5 INCHES
IS POSSIBLE FOR SUNDAY THROUGH SUNDAY NIGHT WITH LOCALIZED AREAS OF
EVEN HEAVIER RAIN POSSIBLE IS SOME CONVECTIVE ELEMENTS CAN DEVELOP.
CONDITIONS WILL REMAIN MUCH WARMER/MOISTER THAN RECENT DAYS THROUGH
SUNDAY WITH HIGHS ONCE AGAIN EXPECTED TO BE IN THE UPPER 40S TO
AROUND 50F.
THE MODELS HAVE SETTLED INTO A RELATIVELY CONSISTENT SOLUTION OF
PHASING THE NRN AND SRN STREAM SHORTWAVES OVER THE ERN GREAT LAKES
BY MONDAY MORNING WITH A SFC LOW ARND 980MB DEVELOPING. AS THE LOW
DEEPENS FURTHER ON MONDAY...STRONG WEST WINDS WILL DEVELOP OVER THE
AREA WITH WINDS INCREASING TO ARND 25 MPH WITH 35MPH GUSTS.
CONSIDERING A POSSIBILITY THAT THE MODELS COULD EVEN BE UNDER
FORECASTING THE POTENTIAL DEEPENING OF THIS LOW...WHICH IS A
POSSIBILITY GIVEN THE LATE FALL CONTRAST OF WARM...MOIST GULF AIR
ASSOCIATED WITH THE SRN STREAM SYSTEM AND MUCH COLDER AIR WITH THE
NRN STREAM SYSTEM...THERE IS THE CHANCE THAT WIND ADVISORY CRITERIA
WINDS OF SUSTAINED 30 MPH WINDS WITH 45 MPH GUSTS MAY OCCUR ON
MONDAY.
THE DEEP SFC LOW IS EXPECTED TO LIFT OUT TO THE NORTHEAST MONDAY
NIGHT AND TUESDAY...WEAK HIGH PRESSURE WILL BUILD ACROSS THE PLAINS
AS THE SFC WHILE BROAD UPPER TROUGHING DEVELOPS OVER THE CNTRL
CONUS. THE UPPER LEVEL PATTERN IS EXPECTED TO BECOME MORE
AMPLIFIED...BUT SLOWLY PROGRESSIVE BY MIDWEEK THROUGH THE END OF NEXT
WEEK...THE AREA REMAINING UNDER PERSISTENT NWLY FLOW AND COLD
ADVECTION ALOFT. SO THE WEEKEND WARMUP SHOULD COME TO AN ABRUPT END
BY MONDAY AS A STRONG COLD FRONT PASSES THROUGH THE REGION AND
TEMPERATURES DROP BACK INTO THE UPPER 30S TO ARND 40F ON MONDAY WITH
HIGHS ONLY IN THE UPPER 20S TO LOWER 30S FOR TUESDAY. THROUGH THE
REMAINDER OF NEXT WEEK...THE TEMPERATURE TREND WILL GO BACK TO WELL
BELOW NORMAL...WITH HIGHS ON THANKSGIVING ONLY IN THE LOWER TO
MIDDLE 20S. A WEAK CLIPPER-TYPE SYSTEM DROPPING OUT OF THE NRN
ROCKIES ON TUESDAY IS EXPECTED TO DIVE INTO THE LOWER MISSISSIPPI
VALLEY BY WEDNESDAY AS ANOTHER WEAK SHORTWAVE DROPS THROUGH THE
UPPER GREAT LAKES. THIS COULD BRING SOME LIGHT SNOW FOR
WEDNESDAY...BUT THEN STRONG HIGH PRESSURE SHOULD BUILD ACROSS THE
MIDDLE MISSISSIPPI VALLEY THROUGH THE GREAT LAKES. THIS COULD SET
UP A WEAK PRESSURE GRADIENT PATTERN OVER THE REGION...BRINGING THE
POSSIBILITY FOR A LAKE EFFECT PLUME TO DEVELOP OVER LAKE MICHIGAN.
WHILE IT IS STILL WAY TOO EARLY TO CONSIDER THE FINER DETAILS OF
LAKE EFFECT SNOW ASSOCIATED WITH MESOSCALE BANDING OF A LAKE
PLUME...THE PATTERN WOULD BE CONDUCIVE FOR SUCH TYPE OF DEVELOPMENT.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* COVERAGE OF FREEZING RAIN SHOWERS INCREASES AFTER AROUND 06Z.
DRY AIR MAY LIMIT ACTIVITY TO FREEZING SPRINKLES INITIALLY.
* TEMPS EXPECTED TO RISE ABOVE FREEZING BY 12Z.
* CIGS LOWER TO MVFR INTO THE OVERNIGHT WITH A GOOD CHANCE FOR IFR
SATURDAY MORNING.
* LOW LEVEL WIND SHEAR POSSIBLE TONIGHT WITH WINDS INCREASING TO
45 KT AROUND 2000 FT AGL.
* LIQUID RAIN SHOWERS LINGER SATURDAY MORNING WITH DRIZZLE
POSSIBLE THROUGH THE DAY.
MDB
//DISCUSSION...UPDATED 00Z...
FREEZING RAIN SHOWERS ARE EXPECTED TO ARRIVE TOWARD 06Z BUT VERY
DRY AIR IN THE LOW LEVELS MAY LIMIT HOW MUCH ACTUALLY REACHES THE
GROUND INITIALLY. MUCH OF THE EARLY ACTIVITY MAY FALL AS
SPRINKLES. DO EXPECT THAT COVERAGE WILL INCREASE OVERNIGHT WITH
MOISTENING ALLOWING FREEZING RAIN TO OCCUR AT THE SURFACE AT THE
TERMINALS. SURFACE AIR TEMPS WILL BE WARMING OVERNIGHT AND LATEST
TRENDS SUPPORT A RISE ABOVE FREEZING BY 12Z OR SO. SHOWERS WILL
LIKELY LINGER BEYOND 12Z AND BE POSSIBLE THROUGH MIDDAY OR EVEN
MUCH OF THE AFTERNOON...WITH DRIZZLE POSSIBLE AS WELL.
CIGS WILL LOWER THROUGH THE NIGHT WITH MVFR EXPECTED EARLY
TONIGHT. FURTHER LOWERING TO IFR IS EXPECTED SATURDAY MORNING AND
THERE ARE MIXED SIGNALS ON WHETHER IT WILL IMPROVE TO MVFR GOING
INTO THE AFTERNOON OR NOT. IF DRIZZLE CAN BE MORE PERSISTENT THEN
IFR MAY REMAIN THROUGH THE AFTERNOON. CONDITIONS MAY LOWER WITH
FOG DEVELOPING SATURDAY EVENING BEFORE WIDESPREAD RAIN ARRIVES
LATE SUNDAY NIGHT. SOUTH WINDS WILL INCREASE SLIGHTLY INTO THE
OVERNIGHT WHILE WINDS ABOVE THE SURFACE NEAR 2000 FT INCREASE TO
45 KT LEADING TO DECENT LOW LEVEL WIND SHEAR POTENTIAL THROUGH
DAYBREAK.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* HIGH CONFIDENCE IN FREEZING RAIN SHOWERS INCREASING IN COVERAGE
AFTER ABOUT 06Z.
* MEDIUM-HIGH CONFIDENCE IN TEMPS WARMING ABOVE FREEZING BY 12Z.
* HIGH CONFIDENCE IN CIGS LOWERING TO MVFR TONIGHT. MEDIUM
CONFIDENCE IN A PERIOD OF IFR SATURDAY MORNING...LOW CONFIDENCE
IN DURATION.
* HIGH CONFIDENCE IN 45 KT WINDS AT 2000 FT AGL TONIGHT.
* MEDIUM CONFIDENCE IN INTERMITTENT RAIN SHOWERS/DRIZZLE SATURDAY.
MDB
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY...RAIN. HEAVY AT TIMES. IFR LIKELY. GUSTY S TO SE WINDS.
MONDAY...CHANCE -RASN EARLY AND -SN LATER. MVFR CIGS POSSIBLE.
GUSTY W TO SW WINDS.
TUESDAY...CHANCE OF FLURRIES. MVFR CIGS PSBL. BREEZY WEST WINDS.
WEDNESDAY...LIGHT SNOW POSSIBLE. MVFR CIGS/VIS POSSIBLE. WEST TO
SOUTHWEST WINDS 10 KT OR LESS.
THANKSGIVING DAY...VFR LIKELY.
MDB
&&
.MARINE...
242 PM...HIGH PRESSURE OVER THE SOUTHERN LAKES AND OHIO VALLEY
WILL MOVE SOUTHEAST TONIGHT REACHING THE CAROLINA COAST ON
SATURDAY AS LOW PRESSURE MOVES ACROSS NORTHERN ONTARIO AND JAMES
BAY TONIGHT. THE GRADIENT BETWEEN THESE TWO SYSTEMS WILL STEADILY
INCREASE OVER LAKE MICHIGAN TONIGHT WITH GALE FORCE WINDS
EXPECTED...POSSIBLY GUSTING AS HIGH AS 45KTS ACROSS THE NORTHERN
PORTION OF THE LAKE. THE GRADIENT WILL BEGIN TO WEAKEN LATER
SATURDAY AFTERNOON INTO SATURDAY EVENING...BUT ANOTHER LOW MOVING
ACROSS THE NORTHERN PLAINS SATURDAY NIGHT INTO SUNDAY WILL TIGHTEN
THE SOUTHERLY GRADIENT AGAIN. THIS LOW WILL BEGIN TO WEAKEN SUNDAY
EVENING AND THEN BE ABSORBED BY ANOTHER STRONGER LOW WHICH WILL
DEVELOP OVER THE SOUTHERN PLAINS SATURDAY NIGHT INTO SUNDAY...THEN
MOVE NORTH ACROSS LAKE MICHIGAN SUNDAY NIGHT INTO MONDAY MORNING.
THIS LOW HAS BEEN FORECAST TO DEEPEN TO AS LOW AS 975MB NEAR LAKE
SUPERIOR FOR SEVERAL DAYS. IF THIS OCCURS...WESTERLY HIGH END
GALES TO 45 KTS WOULD LIKELY DEVELOP MONDAY WITH THE POTENTIAL FOR
SOME STORM FORCE WINDS OR GUSTS. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FREEZING RAIN ADVISORY...ILZ019-ILZ021-ILZ023-ILZ032-ILZ033-
ILZ039 UNTIL 6 AM SATURDAY.
FREEZING RAIN ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-
ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ020-ILZ022...11 PM
FRIDAY TO 9 AM SATURDAY.
IN...FREEZING RAIN ADVISORY...INZ001-INZ002...11 PM FRIDAY TO 9 AM
SATURDAY.
FREEZING RAIN ADVISORY...INZ010-INZ011-INZ019 UNTIL 6 AM
SATURDAY.
LM...GALE WARNING...LMZ080-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ872-
LMZ874-LMZ876-LMZ878 UNTIL 9 AM SATURDAY.
GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ669-LMZ868-LMZ870 UNTIL 9 AM SATURDAY.
SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 3 PM SATURDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
222 AM CST THU NOV 20 2014
.UPDATE...854 PM CST
SNOW SHOWER ACTIVITY WILL BE EXITING THE AREA OVER THE NEXT FEW
HOURS WITH SATELLITE SHOWING SOME SUBSTANTIAL GAPS DEVELOPING IN
THE OVERCAST TO THE WEST AND NORTH. EXPECT THAT THERE WILL BE A
PERIOD OF SCATTERING/CLEARING INTO THE EARLY OVERNIGHT BEFORE
ANOTHER AREA OF CLOUD COVER CURRENTLY OVER THE MN/WI BORDER REGION
WORKS SOUTHEAST ACROSS NORTHEASTERN PORTIONS OF THE AREA.
SOUTHWEST AREAS SHOULD SEE MORE PERIODIC GAPS IN COVERAGE
OVERNIGHT. MAINTAINED LOW TEMPS THOUGH ADJUSTED HOURLY TRENDS WITH
CLEARING LIKELY BRINGING A QUICK FEW DEGREE DROP BASED ON UPSTREAM
TRENDS...BUT STEADY WINDS WILL LIMIT MORE OF A DROP.
MDB
&&
.SHORT TERM...
300 PM...COLD FRONT WELL EAST OF THE AREA THIS AFTERNOON WITH
SCATTERED LIGHT SNOW SHOWERS AND FLURRIES AS ANOTHER PUNCH OF
COLDER AIR SPREADS ACROSS THE REGION WITH SLOWLY FALLING TEMPS
THIS AFTERNOON. EXTENSIVE CLOUD COVER BACK THROUGH THE UPPER
MIDWEST AND EXPECT MOSTLY CLOUDY SKIES INTO THE OVERNIGHT HOURS
WITH SOME SCATTERING ACROSS THE SOUTHWEST TOWARD MORNING. FLURRIES
AND FEW SNOW SHOWERS WILL ALSO CONTINUE THIS EVENING AND POSSIBLY
INTO THE OVERNIGHT HOURS BUT ONLY A DUSTING...AT THE MOST...WILL
BE POSSIBLE IN SOME LOCATIONS.
WINDS HAVE ALSO INCREASED WITH GUSTS 35 TO 40 MPH IN MANY
LOCATIONS. THE STRONGEST WINDS WILL DIMINISH WITH SUNSET...BUT IT
WILL STILL REMAIN QUITE BLUSTERY THROUGH THE EVENING WITH WINDS
STILL IN THE 10-15 MPH OVERNIGHT. THESE WINDS COMBINED WITH THE
EXPECTED CLOUD COVER WILL LIKELY KEEP LOW TEMPS IN THE TEENS BY
MORNING...THOUGH WIND CHILLS WILL BE AROUND ZERO.
STILL BREEZY ON THURSDAY WITH HIGHS STRUGGLING INTO THE MID 20S
WITH A RIDGE OF HIGH PRESSURE MOVING ACROSS THE AREA THURSDAY
NIGHT. WITH MOSTLY CLEAR SKIES AND LIGHT WINDS...TEMPS WILL
LIKELY TANK WITH LOWS IN THE SINGLE DIGITS IN MANY LOCATIONS BY
FRIDAY MORNING. WINDS TURN LIGHT SOUTHERLY FRIDAY AS THE HIGH
DEPARTS WITH TEMPS REBOUNDING BACK INTO THE UPPER 20S TO NEAR 30
ACROSS THE SOUTH WITH SOME SUNSHINE AT LEAST THRU EARLY AFTERNOON.
CMS
&&
.LONG TERM...
300 PM...MULTIPLE FORECAST CONCERNS AND CHALLENGES INCLUDING
FREEZING RAIN FRIDAY NIGHT/EARLY SATURDAY MORNING...POSSIBLE
HEAVY RAIN SUNDAY...FOG SATURDAY NIGHT INTO SUNDAY...THEN
POSSIBLE VERY STRONG WINDS SUNDAY NIGHT INTO MONDAY.
BROAD WEAK LIFT COMBINED WITH STRONG WARM AIR ADVECTION WILL
ALLOW LIGHT PRECIPITATION TO BEGIN FALLING FRIDAY EVENING...FROM
SOUTH TO NORTH ACROSS THE AREA. AFTER A WEEK AND A HALF OF MAINLY
SUB FREEZING TEMPS AND HIGH TEMPS NOT EXPECTED TO REACH FREEZING
FRIDAY AFTERNOON...IN ADDITION TO VERY DRY LOW LEVELS...SURFACES
AND SURFACE TEMPERATURES WILL BE BELOW FREEZING AS PRECIPITATION
BEGINS FRIDAY EVENING. SOUNDINGS SHOW A VERY DEEP WARM LAYER SO
WHILE THERE COULD BE A LITTLE SLEET AT ONSET...BULK OF PRECIP
SHOULD BE LIGHT FREEZING RAIN.
RATHER GOOD CONSISTENCY FROM THE GEM/GFS/ECMWF OF BOTH TEMPS AND
DEWPOINTS SLOWLY BUT STEADILY RISING LATE FRIDAY NIGHT INTO EARLY
SATURDAY MORNING AND HAVE THE FREEZING LINE TO ABOUT THE I-80
CORRIDOR BY 12Z SATURDAY MORNING...WHICH IS ACTUALLY SLOWER/COLDER
THAN THESE MODELS. THE NAM KEEPS TEMPS WELL BELOW FREEZING INTO
MID MORNING SATURDAY AND CONSIDERING WINDS ARE ALL SOUTHERLY
DURING THIS EVENT...WARMER/MORE MOIST AIR MIGHT ARRIVE SOONER
RATHER THAN LATER. NEVERTHELESS...ANY AMOUNT OF ICING WILL CAUSE
SIGNIFICANT PROBLEMS...SO AS THIS TIME PERIOD APPROACHES...THESE
TRENDS WILL BECOME MORE IMPORTANT FOR PRECIP TIMING/DURATION.
AS TEMPS AND DEWPOINTS CONTINUE TO INCREASE SATURDAY...HIGHS MAY
REACH THE MID 40S BUT WILL LIKELY BE ACCOMPANIED BY PERIODS OF
LIGHT RAIN OR DRIZZLE. WITH NO CHANGES SATURDAY NIGHT...THIS MOIST
AIR OVER THE COLD GROUND WILL LIKELY RESULT IN FOG AND ADDED THIS
TO THE FORECAST. HOW DENSE IT BECOMES OR HOW LONG IT PERSISTS IS
A BIT UNCERTAIN THOUGH.
LOW PRESSURE WILL DEVELOP OVER THE SOUTHERN PLAINS SATURDAY NIGHT
AND TURN NORTH AND DEEPEN AS IT REACHES NORTHERN IL SUNDAY
AFTERNOON INTO SUNDAY EVENING. THE LOW CONTINUES TO DEEPEN TO AS
LOW AS 973MB BY MONDAY MORNING OVER NORTHEAST WI AS SHOWN BY THE
12Z GFS/ECMWF. WHILE PLENTY WARM ENOUGH FOR NO WINTER PRECIP
CONCERNS AS IT MOVES ACROSS THE AREA...THE TRACK WILL BE IMPORTANT
REGARDING WHERE THE HEAVIEST RAINS FALL. PRECIPITABLE WATER VALUES
REACH INTO THE 1.0 TO 1.2 INCH RANGE BY SUNDAY AFTERNOON ALONG
WITH EVENT TOTAL QPF FROM THE MODELS IN THE 1 TO 2 INCH RANGE OVER
PARTS OF THE REGION...ESPECIALLY TO THE WEST AND SOUTHWEST. TOO
EARLY FOR SPECIFIC RAINFALL AMOUNTS...BUT GIVEN THE AMOUNT OF
MOISTURE TO WORK WITH...HEAVY RAINFALL WILL BE A POSSIBILITY AND
IF THIS DOES MATERIALIZE...IT WILL BE FALLING ONTO FROZEN OR
PARTIALLY FROZEN GROUND. THUS...AS THIS TIME PERIOD APPROACHES...
HYDRO ISSUES MAY BECOME A CONCERN.
AFTER THE LOW PASSES...FORECAST SOUNDINGS SUGGEST VERY STRONG
WINDS AND GUSTS MAY DEVELOP SUNDAY NIGHT AND CONTINUE MONDAY AND
MONDAY NIGHT. AS COLDER AIR SPREADS ACROSS THE REGION SUNDAY NIGHT
INTO MONDAY...LINGERING LIGHT RAIN WILL MIX WITH THEN CHANGE TO
LIGHT SNOW. WHILE THE DETAILS ARE STILL SEVERAL DAYS AWAY...THERE
DOES APPEAR TO BE SOME POTENTIAL FOR LIGHT SNOW OR SNOW SHOWERS BY
MONDAY AFTERNOON INTO MONDAY EVENING. COLD AND BELOW NORMAL TEMPS
WILL THEN CONTINUE THROUGH MID WEEK. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* GUSTY WEST WINDS CONTINUE THROUGH TOMORROW AFTN WITH MAX GUSTS
ARND 21 KT.
JEE
//DISCUSSION...UPDATED 06Z...
HIGH PRESSURE IS TO OUR WEST AND IT WILL PASS TO THE SOUTH THIS
EVENING. THE PRESSURE GRADIENT REMAINS TIGHT BETWEEN THE HIGH AND
A LOW OVER SOUTHEAST ONTARIO...SO EXPECTING GUSTY WEST WINDS TO
CONTINUE THROUGH THIS AFTERNOON. THE GRADIENT WEAKENS AS THE
HIGH PASSES TO THE SOUTH THIS EVENING. MAY EVEN SEE WINDS BECOME
LIGHT AND VARIABLE TO EVEN CALM LATE TONIGHT.
FOR CIGS DID NOT MAKE MANY CHANGES AS A PERIOD OF LOW END VFR CIGS
ARE POSSIBLE DURING THE DAY. THEY WILL SCATTER OUT IN THE EVENING
WITH SCT OR LESS CLOUDS TONIGHT.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS.
JEE
//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
FRIDAY...CHANCE FOR LIGHT FREEZING PRECIP AND/OR ICE PELLETS LATE
EVENING AND OVERNIGHT. SOUTH WINDS.
SATURDAY...PERIODS OF RAIN AND DRIZZLE LIKELY WITH FOG DEVELOPING
DURING THE NIGHT. AT LEAST TEMPORARY IFR LIKELY.
SOUTH-SOUTHWEST WINDS.
SUNDAY...IFR AND RAIN. GUSTY SOUTHEAST WINDS.
MONDAY...CHANCE OF RAIN AND SNOW. MVFR POSSIBLE. STRONG SOUTHWEST
WINDS.
TUESDAY...CHANCE OF LIGHT SNOW. MVFR POSSIBLE. WEST WINDS.
MTF
&&
.MARINE...
221 AM CST
HEADLINES...WILL CONTINUE THE OPEN WATER GALE WARNING INTO THIS
MORNING AS WELL AS THE SMALL CRAFT ADVISORY THROUGH FRIDAY. WINDS
AND WAVES WILL PROBABLY COME DOWN BEFORE THE END OF THE SMALL CRAFT
ADVSY...BUT WILL LEAVE IT AS IS FOR NOW. ISSUED YET ANOTHER GALE
WATCH FOR SATURDAY EVENING THROUGH MID SATURDAY MORNING FOR THE
NORTHERN 2/3 OF THE LAKE. GALES ARE ALSO POSSIBLE LATE SUNDAY NIGHT
THROUGH MONDAY NIGHT AS A LOW PRESSURE SYSTEM SLIDES UP THE
LAKE...BUT IT IS TOO SOON TO ISSUE A HEADLINE NOW. ANOTHER SMALL
CRAFT ADVISORY MAY ALSO BE NEEDED FRIDAY NIGHT INTO SATURDAY NIGHT
AND AGAIN SUNDAY THROUGH AT LEAST TUESDAY NIGHT. MAY HAVE TO EXTEND
IT INTO WEDNESDAY IF WAVES TAKE LONGER TO SUBSIDE.
LOW PRESSURE IS OVER SOUTHEAST ONTARIO WHILE HIGH PRESSURE STRETCHES
FROM THE NORTHERN PLAINS THROUGH THE SOUTHEAST U.S. WEST WINDS WILL
DIMINISH TO BELOW GALE FORCE THIS MORNING. THEN THE HIGH PASSES
SOUTH OF THE LAKE LATE TONIGHT WITH WINDS CONTINUING TO DIMINISH AND
BECOME SOUTH TO SOUTHWEST BEHIND THE HIGH. A LOW PRESSURE SYSTEM
PASSES OVER CENTRAL MANITOBA TONIGHT REACHING HUDSON BAY SATURDAY
MORNING. THE PRESSURE GRADIENT TIGHTENS BETWEEN THE LOW AND
DEPARTING HIGH WHICH MAY LEAD TO GALE FORCE GUSTS OVER THE NORTHERN
2/3 OF THE LAKE.
SOUTHWEST WINDS DIMINISH SATURDAY AND BECOME SOUTHEAST AHEAD OF THE
NEXT SYSTEM. A LARGE LOW SPREADS OVER THE PLAINS SUNDAY MORNING AND
FORMS A CLOSED LOW OVER NORTHERN IL SUNDAY EVENING. GUIDANCE STILL
DIFFERS ON THE EXACT STRENGTH AND PATH OF THIS LOW...BUT BOTH MODELS
INDICATE THE LOW WILL DEEPEN TO AROUND 975 MB/28.8 INCHES AT THE
NORTH END OF THE LAKE MONDAY AFTERNOON. EXPECTING SOUTHEAST WINDS
TO INCREASE TO AT LEAST 30 KT THROUGH SUNDAY EVENING AND THEN BECOME
SOUTHWEST BEHIND THE LOW. GALES ARE EXPECTED BY LATE SUNDAY NIGHT
AND DEPENDING ON THE PATH AND STRENGTH OF THE LOW...STORM FORCE
WINDS MAY BE INCLUDED IN FUTURE FORECASTS. GUIDANCE INDICATED A
BRIEF PERIOD OF HIGH END GALES OVER THE NORTHERN END OF THE LAKE
MONDAY AFTERNOON SO KEPT WINDS IN THE GALE RANGE FOR NOW. THE LOW
MOVES OVER QUEBEC TUESDAY WITH WEST WINDS DIMINISHING TO BELOW GALES
EARLY TUESDAY MORNING. HIGH PRESSURE MOVES OVER THE LAKE MID NEXT
WEEK HOPEFULLY BRINGING WITH A MUCH NEEDED BREAK.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM THURSDAY.
GALE WATCH...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ669-LMZ868-LMZ870...6 PM FRIDAY TO 9 AM SATURDAY.
SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 2 PM FRIDAY.
&&
$$
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1143 PM CST Wed Nov 19 2014
.UPDATE...
ISSUED AT 900 PM CST WED NOV 19 2014
Flurries continue to affect much of central IL this evening under
a weak shortwave in the strong W-NW flow. A band of low clouds
associated with the feature will persist the rest of the evening
and most likely well after midnight before dry air above the cloud
layer creates some clearing. Satellite images show breaks in the
clouds upstream, so periods of clearing should progress across the
area later tonight. That clearing and some decrease in wind speeds
should help low temps dip to forecast numbers in the mid-upper
teens by sunrise Thursday. W-NW winds of 8-12 mph will push wind
chill readings down into the single digits after midnight.
High pressure will advance east into IL on Thursday, providing
mostly clear skies and continued cold conditions. However, winds
should be lighter under the ridge axis and weaker pressure gradient.
Updates this evening were mainly to the sky grids to match
expected trends. We kept clouds around longer after midnight, but
still expect clearing for tomorrow morning. Updated info is
already available.
&&
.SHORT TERM...(Tonight)
ISSUED AT 254 PM CST WED NOV 19 2014
Breezy and cold weather will be the rule across central Illinois
tonight. 19z/1pm surface analysis shows cold front exiting into
Indiana, while ridge of high pressure builds into the Plains.
Pressure gradient between these two features will continue to create
W/NW wind gusts of 25 to 35 mph this afternoon. Gustiness will
begin to subside toward sunset: however, with ridge axis staying
west of Illinois until Thursday, gradient will remain tight enough
to support winds of around 10 mph through the night. Clouds and a
few flurries will prevail early in the evening, with the big weather
question being how fast skies will clear later tonight. Widespread
cloud cover is currently evident on satellite imagery from Illinois
northwestward to the US/Canada border: however, several holes in the
overcast have developed upstream across the Dakotas/Minnesota. All
model guidance suggests clouds will begin to scatter this evening,
with mostly clear conditions expected overnight. Given current
satellite imagery and continued deep northwesterly flow, think this
is too fast. Have therefore gone with a slower clearing trend more
in line with the HRRR solution. End result will be cloudy skies
this evening, followed by gradual clearing overnight. Due to the
clouds and continued breeze, have gone with the higher end of
numeric guidance for lows tonight, with readings ranging from 14
degrees in Galesburg to around 20 degrees south of I-70.
&&
.LONG TERM...(Thursday through Wednesday)
ISSUED AT 254 PM CST WED NOV 19 2014
Moisture channel satellite imagery and the morning upper air shows
deep upper level trof over eastern US with main jet from central
Canada into the midwest. This upper flow will bring in another surge
of cold air, with cold surface high moving into region during the
day Thursday and Thursday night. With clear skies by Thursday night,
have lowered Friday morning lows some due to light winds and cold
airmass.
Main precipitation concern is for Friday evening and Friday night,
as overrunning precipitation develops from AR into MO ahead of
digging shortwave in the southwest US. Precipitation will reach
central IL Friday evening, so temperature forecast will be critical,
as warm air aloft will produce precipitation in form of rain.
A detailed look at the model surface temperature forecasts depicts
EUR warmest, GFS, and NAM coolest. Feel the warming temperatures
will be blend of GFS and NAM, as conditions will start off cooler
Friday morning, as lowered morning lows. Feel current forecast grids
a good compromise and so looks like pcpn will start in evening
Friday as light freezing rain, with the freezing line gradually
moving to the northeast overnight. Pcpn amounts still look to be
light, so impacts will be on the light scale.
Saturday pcpn will be rain, as overrunning pcpn continues to develop
and move into the region. Strongest dynamics look to be on Sunday,
as the shortwave system and surface low approach and move through
region.
Models are similar in the movement of system, with low center
tracking just west of the cwa Sunday, with front moving through area
and gusty winds. Vertical stacking of the upper low over Lake MI on
Sunday night.
Cool conditions will conditions into midweek, as the upper low
gradually moves off and allows another cool high pressure area into
the midwest.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
ISSUED AT 1143 PM CST WED NOV 19 2014
Winds have finally diminished as pressure rises slowed down and
the pressure gradient relaxed a bit, especially across the SW half
of IL. We expect west winds in the 8-10kt range for the rest of
the night.
The latest satellite imagery shows diminishing clouds to the W-NW
compared to earlier this evening. We still have a majority of
central IL with some VFR cloud cover in the 3.5k-4.5k ft layer,
but breaks are becoming more numerous with each passing hour. Forecast
soundings remain generally pessimistic with cloud cover the rest of the
night, but we continued with clearing developing at all terminal
sites before sunrise.
Once the skies clear out, we expect enough dry air mixing tomorrow
to prevent any BKN cloud decks from forming, but moisture will
remain in the 2-3k ft layer according to forecast moisture
profiles. Winds will be less gusty than today, but sustained winds
will climb back into the 10-145kt range through the day from the
west. Light winds will develop with sunset tomorrow, as winds
decouple under clear skies and weak high pressure.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Shimon
SHORT TERM...Barnes
LONG TERM...Goetsch
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
953 PM EST FRI NOV 21 2014
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 332 PM EST FRI NOV 21 2014
HIGH PRESSURE WILL PUSH OFF TO THE EAST AS A WARM FRONT AND A STRONG
LOW PRESSURE SYSTEM ENTER FROM THE SOUTHWEST TONIGHT. THIS SYSTEM
WILL KEEP PRECIPITATION IN THE FORECAST THROUGH THE WEEKEND. IN ITS
WAKE...COLDER AND DRIER WEATHER WILL RETURN...THEN A UPPER LEVEL
SYSTEM WILL BRING CHANCES FOR SNOW TO THE AREA NEXT WEDNESDAY
THROUGH THURSDAY.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 953 PM EST FRI NOV 21 2014
PRECIP CONTINUES TO BE SLOW TO MOVE INTO THE AREA AND IS SPOTTY AT
BEST FOR THE MOMENT. HRRR DOES INDICATE AN EXPANSION IN COVERAGE
OVER THE NEXT SEVERAL HOURS BUT CONCURRENTLY BRINGS TEMPERATURES UP
AS IT MOVES THE PRECIP IN. HAVE ADJUSTED MIN TEMPS AND HOURLY TEMPS
AS THE WARM ADVECTION CONTINUES...MANY SITES IN THE SOUTHWEST HAVE
LIKELY ALREADY HIT THEIR MINS FOR THE NIGHT.
WILL CONTINUE TO CARRY FREEZING RAIN IN THE GRIDS WHERE THE HOURLY
TEMPS ARE AT OR BELOW 32 WITH A SMALL MARGIN OF RAIN OR FREEZING
RAIN OWING TO UNCERTAINTY...BUT THIS WILL RESULT IN A VERY SHORT
WINDOW OF ICING THREAT AT ANY ONE LOCATION...LIKELY 2-3 HOURS AT
MOST...MAYBE 4 HOURS IN THE NORTH OR NORTHEAST WHICH HAS A BIT
FURTHER TO GO TO THE FREEZING MARK.
PREVIOUS DISCUSSIONS FOLLOW.
ISSUED AT 657 PM EST FRI NOV 21 2014
WITH REGIONAL RADAR TRENDS VERY SLOW TO SHOW ANY ECHOES AT
ALL AND DEWPOINTS REMAINING VERY DRY ACROSS THE AREA...HAVE PUSHED
BACK POPS AT LEAST A FEW HOURS WITH THIS UPDATE...AND MAY NEED TO
PUSH THEM BACK EVEN MORE DEPENDING ON HOW THINGS EVOLVE OVER THE
NEXT FEW HOURS. HRRR DOES HAVE SOME PRECIP IN THE FAR SOUTHWEST BY
04Z. IT IS A RACE BETWEEN WARM ADVECTION AND PRECIP ONSET AT THIS
POINT TO DETERMINE WHETHER ANY FREEZING PRECIP WILL FALL. PREVIOUS
DISCUSSION FOLLOWS.
ISSUED AT 332 PM EST FRI NOV 21 2014
FOR THE REST OF THIS AFTERNOON AND EARLY EVENING EXPECT INCREASING
CLOUD COVER FROM SOUTHWEST TO NORTHEAST AS A FRONTAL SYSTEM DRAPED
MOVES CLOSER TO THE FORECAST AREA. MODELS ARE TIMING THE MOISTURE
FROM THIS SYSTEM TO ARRIVE EVEN SLOWER THAN EXPECTED WHICH WILL
IMPACT PRECIP TYPE OVERNIGHT WHERE ONCE WIDESPREAD FREEZING RAIN WAS
EXPECTED. THIS PERIOD OF LIGHT FREEZING RAIN LOOKS LIKE A MUCH
SMALLER WINDOW FOR CENTRAL INDIANA AS WARM AIR ADVECTION REALLY
KICKS IN LATER THIS EVENING AND SURFACE TEMPERATURES BEGIN TO RISE
TO ABOVE FREEZING. THIS COMBINED WITH THE MUCH SLOWER ONSET OF
PRECIP. THE MAIN WINDOW FOR -FZRA RAIN IS 9PM THROUGH 5AM...QUICKLY
CHANGING OVER TO RAIN FROM SW TO NE AS THE WARMER AIR ARRIVES. QPF
AMOUNTS STILL LOOK EXTREMELY LOW...ONLY A FEW HUNDREDTHS OF AN INCH.
OPTED NOT TO ISSUE ANY STATEMENTS NOR HEADLINES FOR THE -FZRA RAIN
BASED ON THIS LATEST GUIDANCE AND WILL CONTINUE TO MONITOR
CONDITIONS UPSTREAM TO SEE IF A SPECIAL WEATHER STATEMENT IS NEEDED.
IN COORDINATION WITH SURROUNDING OFFICES WILL CONTINUE TO MENTION
THE LIGHT FREEZING RAIN AND POTENTIALLY SLICK/ICY ROADS FOR A BRIEF
PERIOD OVERNIGHT IN THE HWO AND WX STORY.
LOW TEMPS WILL OCCUR EARLY THIS EVENING (RANGING FROM MID 20S TO MID
30S) AND QUICKLY INCREASE TO MID 30S TO LOW 40S BY 12Z SAT!
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
ISSUED AT 332 PM EST FRI NOV 21 2014
BY 10-12Z SATURDAY MORNING ALL THE POTENTIAL -FZRA WILL HAVE CHANGED
OVER TO RAIN. AND WARM AIR ADVECTION WILL CONTINUE TO FILTER INTO
THE AREA IN EARNEST THROUGH SATURDAY WITH HIGH TEMPERATURES COMING
IN EVEN WARMER THIS MODEL RUN WITH HIGHS RANGING FROM MID 40S
(NORTH) TO NEARLY THE MID 50S (FAR SOUTH COUNTIES) BY SAT 12Z
THE SURFACE LOW WILL CONTINUE ITS TRACK ACROSS THE MISSISSIPPI
VALLEY ON SATURDAY INTO SATURDAY NIGHT AND THERE CONTINUES TO LOOKS
LIKE A LULL DURING A GOOD PORTION OF THE DAY SATURDAY...SO BACK OFF
ON POPS OVER THE ENTIRE AREA. THE HIGHEST CHANCES FOR RAIN WILL BE
ON SUNDAY AS BEST LIFT FROM WARM FRONT AND LOW PRESSURE MOVES ACROSS
THE AREA. WILL CONTINUE WITH 100 PERCENT POPS...ESPECIALLY FOR THE
SECOND HALF OF SUNDAY.
IN TERMS OF TEMPS...AS MENTIONED ABOVE EXPECT HIGHS TO CLIMB INTO
THE 50S WITH DECENT WARM ADVECTION...AND LOWS TO BE IN THE 40S.
RAIN WILL SLOWLY BEGIN TO TAPER OFF ON MONDAY AS THE SYSTEM SLOWLY
MOST OFF TO THE EAST. COLD AIR WILL THEN MOVE BACK IN MONDAY
NIGHT IN THE WAKE OF THE FRONTAL PASSAGE. COULD SEE A FEW SNOW
SHOWERS IN THE NORTH AS WEAK WAVE MOVES THROUGH. FOR NOW INDICATED
A MIX OF -RA/SN LATE MONDAY AFTERNOON AND SLIGHT CHANCES FOR SNOW
SHOWERS OR FLURRIES ACROSS THE FAR NORTHERN TIER OF COUNTIES
MONDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 255 PM EST FRI NOV 21 2014
COLD AIR WILL MOVE BACK IN MONDAY NIGHT IN THE WAKE OF THE FRONTAL
PASSAGE. COULD SEE A FEW SNOW SHOWERS IN THE NORTH AS WEAK WAVE
MOVES THROUGH. KEPT CHANCE FOR FLURRIES GOING TUESDAY IN THE
NORTHERN HALF OR SO AS WELL WITH CYCLONIC UPPER FLOW. WEDNESDAY ON
MODELS ARE SHOWING SOME DECENT DIFFERENCES IN THE UPPER PATTERN AND
ENSEMBLES ARE PRETTY VARIABLE SO WILL JUST GO WITH INITIALIZATION.
TEMPERATURES DO SEEM TO BE COMING TOGETHER A LITTLE COOLER FOR THAT
TIME SO STUCK WITH SMALL CHANCES FOR SNOW FOR PRECIP TYPE. THERE IS
SOME HINT OF A WARMUP OUT BEYOND FRIDAY BUT THAT REMAINS TO BE SEEN.
&&
.AVIATION /DISCUSSION FOR THE 220300Z IND TAF UPDATE/...
ONGOING TAF APPEARS IN GOOD SHARE AS WARM AIR ADVECTION IS ONGOING
AND CLOUDS OVER THE MID MISSISSIPPI RIVER VALLEY CONTINUE TO TRY
TO ADVECT EAST INTO THE VERY DRY AIR MASS IN PLACE ACROSS INDIANA.
LATEST HRRR SUGGESTS PRECIP ARRIVING IN THE AREA AROUND 08Z-09Z.
SURFACE TEMPS AT THAT TIME SHOULD BE IN THE MIDDLE 30S...WHICH
ONCE AGAIN SUPPORTS JUST RA AS PRECIP TYPE. WILL CONTINUE TO WATCH
CLOSELY.
PREVIOUS DISCUSSION BELOW
/DISCUSSION FOR THE 220000 TAFS/...
ISSUED AT 607 PM EST FRI NOV 21 2014
VFR EXPECTED THE NEXT 6-8 HOURS. A BRIEF PERIOD OF MVFR WILL BE
POSSIBLE FROM 07Z-12Z...BEFORE VFR CONDITIONS RETURN.
LIGHT FREEZING RAIN WILL BE POSSIBLE OVERNIGHT AT LAF.
CLOUDS OVER MISSOURI ASSOCIATED WITH STRONG WARM AIR ADVECTION AND
A STRONG LLJ WILL PUSH INTO THE INDIANA TAF SITES OVERNIGHT.
COLUMN ACROSS THE AREA IS QUITE DRY WITH DEW POINT TEMPS IN THE
SINGLE DIGITS TO LOW TEENS. THUS IT WILL TAKE SOME TIME FOR ANY
PRECIP TO MOIST UP THE COLUMN AS ANY PRECIP MAY START AS VIRGA.
FURTHERMORE...THE STRONG WARM AIR ADVECTION WILL ALLOW TEMPS TO
RISE THROUGH THE NIGHT...LIMITING THE WINDOW FOR ANY FREEZING
PRECIPITATION. DUE TO THIS HAVE FOR NOW HAVE LIMITED THE MENTION FOR
FREEZING RAIN TO THE LAF TAF SITE...WITH JUST RAIN EXPECTED
ELSEWHERE.
TIME HEIGHTS THEN CONTINUE TO SHOW PLENTIFUL LOWER LEVEL MOISTURE
THROUGH THE FORECAST PERIOD AMID WARM AIR ADVECTION WITHIN THE
COLUMN. THUS A RETURN TO VFR WILL BE EXPECTED AFT 12Z WITH SCT
SHOWERS IN THE AREA. A STRONG LLJ OF 50KT WORKING ACROSS THE AREA
MAY RESULT IN SOME LLWS WHICH HAS BEEN INCLUDED.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF/NIELD
SHORT TERM...SMF
LONG TERM...CP
AVIATION...JP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
901 PM EST FRI NOV 21 2014
.UPDATE...
AVIATION SECTION UPDATED.
&&
.SYNOPSIS...
ISSUED AT 332 PM EST FRI NOV 21 2014
HIGH PRESSURE WILL PUSH OFF TO THE EAST AS A WARM FRONT AND A STRONG
LOW PRESSURE SYSTEM ENTER FROM THE SOUTHWEST TONIGHT. THIS SYSTEM
WILL KEEP PRECIPITATION IN THE FORECAST THROUGH THE WEEKEND. IN ITS
WAKE...COLDER AND DRIER WEATHER WILL RETURN...THEN A UPPER LEVEL
SYSTEM WILL BRING CHANCES FOR SNOW TO THE AREA NEXT WEDNESDAY
THROUGH THURSDAY.
&&
.NEAR TERM /REST OF THIS AFTERNOON THROUGH TONIGHT/...
ISSUED AT 657 PM EST FRI NOV 21 2014
WITH REGIONAL RADAR TRENDS VERY SLOW TO SHOW ANY ECHOES AT
ALL AND DEWPOINTS REMAINING VERY DRY ACROSS THE AREA...HAVE PUSHED
BACK POPS AT LEAST A FEW HOURS WITH THIS UPDATE...AND MAY NEED TO
PUSH THEM BACK EVEN MORE DEPENDING ON HOW THINGS EVOLVE OVER THE
NEXT FEW HOURS. HRRR DOES HAVE SOME PRECIP IN THE FAR SOUTHWEST BY
04Z. IT IS A RACE BETWEEN WARM ADVECTION AND PRECIP ONSET AT THIS
POINT TO DETERMINE WHETHER ANY FREEZING PRECIP WILL FALL. PREVIOUS
DISCUSSION FOLLOWS.
ISSUED AT 332 PM EST FRI NOV 21 2014
FOR THE REST OF THIS AFTERNOON AND EARLY EVENING EXPECT INCREASING
CLOUD COVER FROM SOUTHWEST TO NORTHEAST AS A FRONTAL SYSTEM DRAPED
MOVES CLOSER TO THE FORECAST AREA. MODELS ARE TIMING THE MOISTURE
FROM THIS SYSTEM TO ARRIVE EVEN SLOWER THAN EXPECTED WHICH WILL
IMPACT PRECIP TYPE OVERNIGHT WHERE ONCE WIDESPREAD FREEZING RAIN WAS
EXPECTED. THIS PERIOD OF LIGHT FREEZING RAIN LOOKS LIKE A MUCH
SMALLER WINDOW FOR CENTRAL INDIANA AS WARM AIR ADVECTION REALLY
KICKS IN LATER THIS EVENING AND SURFACE TEMPERATURES BEGIN TO RISE
TO ABOVE FREEZING. THIS COMBINED WITH THE MUCH SLOWER ONSET OF
PRECIP. THE MAIN WINDOW FOR -FZRA RAIN IS 9PM THROUGH 5AM...QUICKLY
CHANGING OVER TO RAIN FROM SW TO NE AS THE WARMER AIR ARRIVES. QPF
AMOUNTS STILL LOOK EXTREMELY LOW...ONLY A FEW HUNDREDTHS OF AN INCH.
OPTED NOT TO ISSUE ANY STATEMENTS NOR HEADLINES FOR THE -FZRA RAIN
BASED ON THIS LATEST GUIDANCE AND WILL CONTINUE TO MONITOR
CONDITIONS UPSTREAM TO SEE IF A SPECIAL WEATHER STATEMENT IS NEEDED.
IN COORDINATION WITH SURROUNDING OFFICES WILL CONTINUE TO MENTION
THE LIGHT FREEZING RAIN AND POTENTIALLY SLICK/ICY ROADS FOR A BRIEF
PERIOD OVERNIGHT IN THE HWO AND WX STORY.
LOW TEMPS WILL OCCUR EARLY THIS EVENING (RANGING FROM MID 20S TO MID
30S) AND QUICKLY INCREASE TO MID 30S TO LOW 40S BY 12Z SAT!
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
ISSUED AT 332 PM EST FRI NOV 21 2014
BY 10-12Z SATURDAY MORNING ALL THE POTENTIAL -FZRA WILL HAVE CHANGED
OVER TO RAIN. AND WARM AIR ADVECTION WILL CONTINUE TO FILTER INTO
THE AREA IN EARNEST THROUGH SATURDAY WITH HIGH TEMPERATURES COMING
IN EVEN WARMER THIS MODEL RUN WITH HIGHS RANGING FROM MID 40S
(NORTH) TO NEARLY THE MID 50S (FAR SOUTH COUNTIES) BY SAT 12Z
THE SURFACE LOW WILL CONTINUE ITS TRACK ACROSS THE MISSISSIPPI
VALLEY ON SATURDAY INTO SATURDAY NIGHT AND THERE CONTINUES TO LOOKS
LIKE A LULL DURING A GOOD PORTION OF THE DAY SATURDAY...SO BACK OFF
ON POPS OVER THE ENTIRE AREA. THE HIGHEST CHANCES FOR RAIN WILL BE
ON SUNDAY AS BEST LIFT FROM WARM FRONT AND LOW PRESSURE MOVES ACROSS
THE AREA. WILL CONTINUE WITH 100 PERCENT POPS...ESPECIALLY FOR THE
SECOND HALF OF SUNDAY.
IN TERMS OF TEMPS...AS MENTIONED ABOVE EXPECT HIGHS TO CLIMB INTO
THE 50S WITH DECENT WARM ADVECTION...AND LOWS TO BE IN THE 40S.
RAIN WILL SLOWLY BEGIN TO TAPER OFF ON MONDAY AS THE SYSTEM SLOWLY
MOST OFF TO THE EAST. COLD AIR WILL THEN MOVE BACK IN MONDAY
NIGHT IN THE WAKE OF THE FRONTAL PASSAGE. COULD SEE A FEW SNOW
SHOWERS IN THE NORTH AS WEAK WAVE MOVES THROUGH. FOR NOW INDICATED
A MIX OF -RA/SN LATE MONDAY AFTERNOON AND SLIGHT CHANCES FOR SNOW
SHOWERS OR FLURRIES ACROSS THE FAR NORTHERN TIER OF COUNTIES
MONDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 255 PM EST FRI NOV 21 2014
COLD AIR WILL MOVE BACK IN MONDAY NIGHT IN THE WAKE OF THE FRONTAL
PASSAGE. COULD SEE A FEW SNOW SHOWERS IN THE NORTH AS WEAK WAVE
MOVES THROUGH. KEPT CHANCE FOR FLURRIES GOING TUESDAY IN THE
NORTHERN HALF OR SO AS WELL WITH CYCLONIC UPPER FLOW. WEDNESDAY ON
MODELS ARE SHOWING SOME DECENT DIFFERENCES IN THE UPPER PATTERN AND
ENSEMBLES ARE PRETTY VARIABLE SO WILL JUST GO WITH INITIALIZATION.
TEMPERATURES DO SEEM TO BE COMING TOGETHER A LITTLE COOLER FOR THAT
TIME SO STUCK WITH SMALL CHANCES FOR SNOW FOR PRECIP TYPE. THERE IS
SOME HINT OF A WARMUP OUT BEYOND FRIDAY BUT THAT REMAINS TO BE SEEN.
&&
.AVIATION /DISCUSSION FOR THE 220300Z IND TAF UPDATE/...
ONGOING TAF APPEARS IN GOOD SHARE AS WARM AIR ADVECTION IS ONGOING
AND CLOUDS OVER THE MID MISSISSIPPI RIVER VALLEY CONTINUE TO TRY
TO ADVECT EAST INTO THE VERY DRY AIR MASS IN PLACE ACROSS INDIANA.
LATEST HRRR SUGGESTS PRECIP ARRIVING IN THE AREA AROUND 08Z-09Z.
SURFACE TEMPS AT THAT TIME SHOULD BE IN THE MIDDLE 30S...WHICH
ONCE AGAIN SUPPORTS JUST RA AS PRECIP TYPE. WILL CONTINUE TO WATCH
CLOSELY.
PREVIOUS DISCUSSION BELOW
/DISCUSSION FOR THE 220000 TAFS/...
ISSUED AT 607 PM EST FRI NOV 21 2014
VFR EXPECTED THE NEXT 6-8 HOURS. A BRIEF PERIOD OF MVFR WILL BE
POSSIBLE FROM 07Z-12Z...BEFORE VFR CONDITIONS RETURN.
LIGHT FREEZING RAIN WILL BE POSSIBLE OVERNIGHT AT LAF.
CLOUDS OVER MISSOURI ASSOCIATED WITH STRONG WARM AIR ADVECTION AND
A STRONG LLJ WILL PUSH INTO THE INDIANA TAF SITES OVERNIGHT.
COLUMN ACROSS THE AREA IS QUITE DRY WITH DEW POINT TEMPS IN THE
SINGLE DIGITS TO LOW TEENS. THUS IT WILL TAKE SOME TIME FOR ANY
PRECIP TO MOIST UP THE COLUMN AS ANY PRECIP MAY START AS VIRGA.
FURTHERMORE...THE STRONG WARM AIR ADVECTION WILL ALLOW TEMPS TO
RISE THROUGH THE NIGHT...LIMITING THE WINDOW FOR ANY FREEZING
PRECIPITATION. DUE TO THIS HAVE FOR NOW HAVE LIMITED THE MENTION FOR
FREEZING RAIN TO THE LAF TAF SITE...WITH JUST RAIN EXPECTED
ELSEWHERE.
TIME HEIGHTS THEN CONTINUE TO SHOW PLENTIFUL LOWER LEVEL MOISTURE
THROUGH THE FORECAST PERIOD AMID WARM AIR ADVECTION WITHIN THE
COLUMN. THUS A RETURN TO VFR WILL BE EXPECTED AFT 12Z WITH SCT
SHOWERS IN THE AREA. A STRONG LLJ OF 50KT WORKING ACROSS THE AREA
MAY RESULT IN SOME LLWS WHICH HAS BEEN INCLUDED.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF/NIELD
SHORT TERM...SMF
LONG TERM...CP
AVIATION...JP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
658 PM EST FRI NOV 21 2014
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 332 PM EST FRI NOV 21 2014
HIGH PRESSURE WILL PUSH OFF TO THE EAST AS A WARM FRONT AND A STRONG
LOW PRESSURE SYSTEM ENTER FROM THE SOUTHWEST TONIGHT. THIS SYSTEM
WILL KEEP PRECIPITATION IN THE FORECAST THROUGH THE WEEKEND. IN ITS
WAKE...COLDER AND DRIER WEATHER WILL RETURN...THEN A UPPER LEVEL
SYSTEM WILL BRING CHANCES FOR SNOW TO THE AREA NEXT WEDNESDAY
THROUGH THURSDAY.
&&
.NEAR TERM /REST OF THIS AFTERNOON THROUGH TONIGHT/...
ISSUED AT 657 PM EST FRI NOV 21 2014
WITH REGIONAL RADAR TRENDS VERY SLOW TO SHOW ANY ECHOES AT
ALL AND DEWPOINTS REMAINING VERY DRY ACROSS THE AREA...HAVE PUSHED
BACK POPS AT LEAST A FEW HOURS WITH THIS UPDATE...AND MAY NEED TO
PUSH THEM BACK EVEN MORE DEPENDING ON HOW THINGS EVOLVE OVER THE
NEXT FEW HOURS. HRRR DOES HAVE SOME PRECIP IN THE FAR SOUTHWEST BY
04Z. IT IS A RACE BETWEEN WARM ADVECTION AND PRECIP ONSET AT THIS
POINT TO DETERMINE WHETHER ANY FREEZING PRECIP WILL FALL. PREVIOUS
DISCUSSION FOLLOWS.
ISSUED AT 332 PM EST FRI NOV 21 2014
FOR THE REST OF THIS AFTERNOON AND EARLY EVENING EXPECT INCREASING
CLOUD COVER FROM SOUTHWEST TO NORTHEAST AS A FRONTAL SYSTEM DRAPED
MOVES CLOSER TO THE FORECAST AREA. MODELS ARE TIMING THE MOISTURE
FROM THIS SYSTEM TO ARRIVE EVEN SLOWER THAN EXPECTED WHICH WILL
IMPACT PRECIP TYPE OVERNIGHT WHERE ONCE WIDESPREAD FREEZING RAIN WAS
EXPECTED. THIS PERIOD OF LIGHT FREEZING RAIN LOOKS LIKE A MUCH
SMALLER WINDOW FOR CENTRAL INDIANA AS WARM AIR ADVECTION REALLY
KICKS IN LATER THIS EVENING AND SURFACE TEMPERATURES BEGIN TO RISE
TO ABOVE FREEZING. THIS COMBINED WITH THE MUCH SLOWER ONSET OF
PRECIP. THE MAIN WINDOW FOR -FZRA RAIN IS 9PM THROUGH 5AM...QUICKLY
CHANGING OVER TO RAIN FROM SW TO NE AS THE WARMER AIR ARRIVES. QPF
AMOUNTS STILL LOOK EXTREMELY LOW...ONLY A FEW HUNDREDTHS OF AN INCH.
OPTED NOT TO ISSUE ANY STATEMENTS NOR HEADLINES FOR THE -FZRA RAIN
BASED ON THIS LATEST GUIDANCE AND WILL CONTINUE TO MONITOR
CONDITIONS UPSTREAM TO SEE IF A SPECIAL WEATHER STATEMENT IS NEEDED.
IN COORDINATION WITH SURROUNDING OFFICES WILL CONTINUE TO MENTION
THE LIGHT FREEZING RAIN AND POTENTIALLY SLICK/ICY ROADS FOR A BRIEF
PERIOD OVERNIGHT IN THE HWO AND WX STORY.
LOW TEMPS WILL OCCUR EARLY THIS EVENING (RANGING FROM MID 20S TO MID
30S) AND QUICKLY INCREASE TO MID 30S TO LOW 40S BY 12Z SAT!
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
ISSUED AT 332 PM EST FRI NOV 21 2014
BY 10-12Z SATURDAY MORNING ALL THE POTENTIAL -FZRA WILL HAVE CHANGED
OVER TO RAIN. AND WARM AIR ADVECTION WILL CONTINUE TO FILTER INTO
THE AREA IN EARNEST THROUGH SATURDAY WITH HIGH TEMPERATURES COMING
IN EVEN WARMER THIS MODEL RUN WITH HIGHS RANGING FROM MID 40S
(NORTH) TO NEARLY THE MID 50S (FAR SOUTH COUNTIES) BY SAT 12Z
THE SURFACE LOW WILL CONTINUE ITS TRACK ACROSS THE MISSISSIPPI
VALLEY ON SATURDAY INTO SATURDAY NIGHT AND THERE CONTINUES TO LOOKS
LIKE A LULL DURING A GOOD PORTION OF THE DAY SATURDAY...SO BACK OFF
ON POPS OVER THE ENTIRE AREA. THE HIGHEST CHANCES FOR RAIN WILL BE
ON SUNDAY AS BEST LIFT FROM WARM FRONT AND LOW PRESSURE MOVES ACROSS
THE AREA. WILL CONTINUE WITH 100 PERCENT POPS...ESPECIALLY FOR THE
SECOND HALF OF SUNDAY.
IN TERMS OF TEMPS...AS MENTIONED ABOVE EXPECT HIGHS TO CLIMB INTO
THE 50S WITH DECENT WARM ADVECTION...AND LOWS TO BE IN THE 40S.
RAIN WILL SLOWLY BEGIN TO TAPER OFF ON MONDAY AS THE SYSTEM SLOWLY
MOST OFF TO THE EAST. COLD AIR WILL THEN MOVE BACK IN MONDAY
NIGHT IN THE WAKE OF THE FRONTAL PASSAGE. COULD SEE A FEW SNOW
SHOWERS IN THE NORTH AS WEAK WAVE MOVES THROUGH. FOR NOW INDICATED
A MIX OF -RA/SN LATE MONDAY AFTERNOON AND SLIGHT CHANCES FOR SNOW
SHOWERS OR FLURRIES ACROSS THE FAR NORTHERN TIER OF COUNTIES
MONDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 255 PM EST FRI NOV 21 2014
COLD AIR WILL MOVE BACK IN MONDAY NIGHT IN THE WAKE OF THE FRONTAL
PASSAGE. COULD SEE A FEW SNOW SHOWERS IN THE NORTH AS WEAK WAVE
MOVES THROUGH. KEPT CHANCE FOR FLURRIES GOING TUESDAY IN THE
NORTHERN HALF OR SO AS WELL WITH CYCLONIC UPPER FLOW. WEDNESDAY ON
MODELS ARE SHOWING SOME DECENT DIFFERENCES IN THE UPPER PATTERN AND
ENSEMBLES ARE PRETTY VARIABLE SO WILL JUST GO WITH INITIALIZATION.
TEMPERATURES DO SEEM TO BE COMING TOGETHER A LITTLE COOLER FOR THAT
TIME SO STUCK WITH SMALL CHANCES FOR SNOW FOR PRECIP TYPE. THERE IS
SOME HINT OF A WARMUP OUT BEYOND FRIDAY BUT THAT REMAINS TO BE SEEN.
&&
.AVIATION /DISCUSSION FOR THE 220000 TAFS/...
ISSUED AT 607 PM EST FRI NOV 21 2014
VFR EXPECTED THE NEXT 6-8 HOURS. A BRIEF PERIOD OF MVFR WILL BE
POSSIBLE FROM 07Z-12Z...BEFORE VFR CONDITIONS RETURN.
LIGHT FREEZING RAIN WILL BE POSSIBLE OVERNIGHT AT LAF.
CLOUDS OVER MISSOURI ASSOCIATED WITH STRONG WARM AIR ADVECTION AND
A STRONG LLJ WILL PUSH INTO THE INDIANA TAF SITES OVERNIGHT.
COLUMN ACROSS THE AREA IS QUITE DRY WITH DEW POINT TEMPS IN THE
SINGLE DIGITS TO LOW TEENS. THUS IT WILL TAKE SOME TIME FOR ANY
PRECIP TO MOIST UP THE COLUMN AS ANY PRECIP MAY START AS VIRGA.
FURTHERMORE...THE STRONG WARM AIR ADVECTION WILL ALLOW TEMPS TO
RISE THROUGH THE NIGHT...LIMITING THE WINDOW FOR ANY FREEZING
PRECIPITATION. DUE TO THIS HAVE FOR NOW HAVE LIMITED THE MENTION FOR
FREEZING RAIN TO THE LAF TAF SITE...WITH JUST RAIN EXPECTED ELSEWHERE.
TIME HEIGHTS THEN CONTINUE TO SHOW PLENTIFUL LOWER LEVEL MOISTURE
THROUGH THE FORECAST PERIOD AMID WARM AIR ADVECTION WITHIN THE
COLUMN. THUS A RETURN TO VFR WILL BE EXPECTED AFT 12Z WITH SCT
SHOWERS IN THE AREA. A STRONG LLJ OF 50KT WORKING ACROSS THE AREA
MAY RESULT IN SOME LLWS WHICH HAS BEEN INCLUDED.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF/NIELD
SHORT TERM...SMF
LONG TERM...CP
AVIATION...JP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
518 PM MST FRI NOV 21 2014
.UPDATE...
ISSUED AT 517 PM MST FRI NOV 21 2014
NICE EVENING ACROSS THE FORECAST AREA WITH PARTLY CLOUDY
CONDITIONS AND TEMPERATURES RANGING FROM THE MID 30S TO LOWER 40S.
HAVE UPDATED CURRENT ZONE FORECAST TO SHOW TREND IN LOW LEVEL
CLOUDS RIGHT ALONG OUR EASTERN ZONES. BASED ON LATEST SATELLITE
LOOP...LOOKING FOR LESS INTRUSION OF THESE CLOUDS BEFORE EXITING
SO HAVE CUT BACK SLIGHTLY...AND WILL MONITOR OVER NEXT COUPLE
HOURS TO SEE IF TREND HOLDS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 138 PM MST FRI NOV 21 2014
MAIN CONCERNS ARE EXTENT OF FOG TONIGHT FOLLOWED BY HOW MUCH TO
WARM UP THE TEMPERATURES ON SATURDAY. LARGE AREA OF STRATUS AND
SOME FOG TO OUR SOUTH AND SOUTHEAST AT THIS TIME. RETURN FLOW WILL
BE IN PLACE BY THE TIME SUN GOES DOWN AND THE LOW LEVEL INVERSION
STRENGTHENS. SO WOULD EXPECT THIS MOISTURE TO BE ABLE TO RETURN
NORTH AND MOVE INTO THE AREA BEFORE THE WINDS SHIFT TO A WEST TO
SOUTHWEST DIRECTION BY LATER TONIGHT AS A SURFACE TROUGH MOVES
THROUGH.
HRRR FOLLOWED BY RAP HAVE BEEN DOING VERY WELL IN THE DEPICTION OF
THIS LOW LEVEL MOISTURE FIELD. BASED ON THAT AND THE OBSERVATIONS
TO OUR SOUTH...WENT AHEAD AND FOLLOWED THE HRRR/RAP VERY CLOSELY
FOR THE CLOUD COVER AND FOG FOR TONIGHT. FOG/LOW CLOUDS SHOULD
STAY IN THE EASTERN HALF TO TWO THIRDS OF THE AREA. IF HRRR ENDS
UP BEING RIGHT THERE COULD BE SOME DENSE FOG POSSIBLE IN THE FAR
EASTERN PORTION.
FOG AND STRATUS DECREASE LATE TONIGHT AND EARLY TOMORROW AS
SURFACE TROUGH MOVES THROUGH AND SHIFTS/INCREASES THE WINDS FROM
THE WEST. AT THIS TIME THE FOG SHOULD END BY MID MORNING. ONCE THE
FOG/CLOUDS CLEAR OFF THERE WILL BE PLENTIFUL SUNSHINE AND
DOWNSLOPE WINDS THROUGH 700 MB. COMBINATION OF DRY AIR MASS AND
GROUND COMBINED WITH THE ABUNDANT SUNSHINE AND DOWNSLOPE WINDS
WILL ALLOW FOR A GOOD WARMUP.
QUESTION IS HOW MUCH. THE NWP AND ESPECIALLY THE 2 METER GUIDANCE
HAS BEEN RUNNING COOL DURING THE LAST WEEK. AT THIS TIME WENT
ABOVE GUIDANCE IN MOST PLACES WITH 60S...MOSTLY MIDDLE AND UPPER
60S....ACROSS THE ENTIRE AREA.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 210 PM MST FRI NOV 21 2014
FOR THE EXTENDED FORECAST PERIOD...VARIABLE WEATHER CONDITIONS ARE
EXPECTED THROUGHOUT DUE TO PASSING COLD FRONTS UNDER A NORTHWEST
FLOW REGIME. OVERALL...THE PATTERN REMAINS FAIRLY CONSISTENT WITH
LITTLE CHANCE OF MAJOR PRECIPITATION-PRODUCING SYSTEMS REACHING THE
REGION. PRIMARY CHANGE TO THIS EXTENDED PACKAGE WAS TO REMOVE
PRECIPITATION CHANCES FOR THANKSGIVING. MORE DETAILS ON THIS BELOW.
FOR SATURDAY NIGHT INTO SUNDAY MORNING...A STRONG COLD FRONT PASSAGE
IS ANTICIPATED. TEMPERATURES WILL BE SLOW TO FALL SATURDAY NIGHT DUE
TO INCREASING CLOUD COVER. THEN...A QUICK DROP IN TEMPERATURES AND
GUSTY NORTH WINDS ARE LIKELY IMMEDIATELY BEHIND THE FRONT. AS THE
FRONT PASSES THROUGH...THE ATMOSPHERE MOISTENS AT LOW LEVELS WHEN
THE COOLER AIR INTRUDES. THERE SHOULD BE ENOUGH MID-LEVEL LIFT AND
MOISTURE FOR RAIN/SNOW SHOWERS DEVELOPMENT BUT THE QUESTION OVER THE
PAST FEW FORECAST RUNS HAS BEEN WHETHER OR NOT THIS PRECIPITATION
REACHES THE GROUND. BASED ON LATEST GUIDANCE...THERE SHOULD BE A
SMALL WINDOW OF OPPORTUNITY FOR MEASURABLE PRECIPITATION TO REACH
THE GROUND AHEAD OF INCOMING POST-FRONTAL DRY AIR. THEREFORE...
PLACED A SLIGHT CHANCE FOR MEASURABLE PRECIPITATION INTO THE
FORECAST AND MAINTAINED SPRINKLES/FLURRIES MENTION SURROUNDING THE
SLIGHT CHANCE POPS.
MAIN STORY FOR THE REST OF SUNDAY THROUGH MONDAY SHOULD BE
BREEZY/WINDY CONDITIONS AND COOL TEMPERATURES. WITH PERSISTENT COLD
AIR ADVECTION AND POSSIBLE CLOUD COVER OVERHEAD...HAVE A HARD TIME
BELIEVING THAT THE REGION WILL BE ABLE TO REACH MEX/MET/ECE GUIDANCE
TEMPERATURES. WENT BELOW GUIDANCE FOR HIGH TEMPERATURES DUE TO THIS
THINKING. REGARDING THE WINDS...MODELS ARE NOT IN STRONG AGREEMENT
WITH RESPECT TO HOW STRONG THE WINDS WILL BE AND WHEN THE STRONGEST
WINDS WILL OCCUR. ANY POSSIBLE CLOUD COVER ALSO MESSES WITH
ANTICIPATED MIXING HEIGHTS SO HARD TO TELL HOW STRONG THE MIXED DOWN
GUSTS WILL BE AT THIS TIME. WITHOUT A STRONG CUT-OFF LOW PRESSURE
SYSTEM PRESENT...CURRENTLY DO NOT BELIEVE THAT THIS WILL BE A MAJOR
WIND EVENT. TYPICAL COLD/WINDY HIGH PLAINS DAYS ARE FORECAST WITH
NORTH WINDS 20-30 MPH...GUSTING TO 45 MPH AND HIGH TEMPERATURES IN
THE LOW TO UPPER 40S.
BEYOND MONDAY...A WEAK UPPER LEVEL DISTURBANCE MOVES THROUGH THE
HIGH PLAINS TUESDAY INTO TUESDAY NIGHT. THE CR INITIALIZATION
PROCEDURE DID NOT INCLUDE POPS AND WITH A DRY LAYER OF AIR AT THE
SURFACE...THOUGHT THIS WAS APPROPRIATE. POPS MAY NEED TO BE INCLUDED
AT A LATER TIME BUT MODEL CONSISTENCY WAS NOT STRONG ENOUGH FOR
INCLUSION WITH THIS RUN.
ANOTHER STRONG UPPER LEVEL DISTURBANCE SWINGS SOUTH OVER THE PLAINS
AND INTO THE MID-MISSISSIPPI VALLEY BY THURSDAY. THIS SYSTEM SHOULD
FORCE A BACKDOOR COLD FRONT INTO THE HIGH PLAINS. IT IS HARD TO TELL
HOW FAR SOUTHWEST THIS FRONT WILL REACH AND THERE IS A STRONG CHANCE
FOR A LARGE TEMPERATURE GRADIENT ACROSS THE REGION. CURRENT
THANKSGIVING FORECAST CALLS FOR A HIGH OF 38 DEGREES AT MCCOOK
NEBRASKA...44 AT GOODLAND KANSAS AND 52 AT KIT CARSON COLORADO.
MODELS TRENDED PRECIPITATION CHANCES FOR THANKSGIVING DOWN AND
BELIEVE THIS IS ACCURATE CONSIDERING A RIDGE OF HIGH PRESSURE WILL
BUILD IN FROM THE WEST.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 433 PM MST FRI NOV 21 2014
KGLD WILL SEE VFR CONDITIONS THROUGH THE FORECAST PERIOD WITH A
MIX OF SKC-SCT150. WINDS SSW AROUND 10KTS.
KMCK WILL SEE MOSTLY VFR CONDITIONS WITH A MIX OF SKC AND
SCT150-250. BKN020 IS POSSIBLE FROM 02Z-04Z SAT. WINDS SOUTH
AROUND 10KTS...BECOMING WSW AROUND 10KTS BY 06Z SAT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JN
SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...JN
AREA FORECAST DISCUSSION
NWS GOODLAND KS
433 PM MST FRI NOV 21 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 138 PM MST FRI NOV 21 2014
MAIN CONCERNS ARE EXTENT OF FOG TONIGHT FOLLOWED BY HOW MUCH TO
WARM UP THE TEMPERATURES ON SATURDAY. LARGE AREA OF STRATUS AND
SOME FOG TO OUR SOUTH AND SOUTHEAST AT THIS TIME. RETURN FLOW WILL
BE IN PLACE BY THE TIME SUN GOES DOWN AND THE LOW LEVEL INVERSION
STRENGTHENS. SO WOULD EXPECT THIS MOISTURE TO BE ABLE TO RETURN
NORTH AND MOVE INTO THE AREA BEFORE THE WINDS SHIFT TO A WEST TO
SOUTHWEST DIRECTION BY LATER TONIGHT AS A SURFACE TROUGH MOVES
THROUGH.
HRRR FOLLOWED BY RAP HAVE BEEN DOING VERY WELL IN THE DEPICTION OF
THIS LOW LEVEL MOISTURE FIELD. BASED ON THAT AND THE OBSERVATIONS
TO OUR SOUTH...WENT AHEAD AND FOLLOWED THE HRRR/RAP VERY CLOSELY
FOR THE CLOUD COVER AND FOG FOR TONIGHT. FOG/LOW CLOUDS SHOULD
STAY IN THE EASTERN HALF TO TWO THIRDS OF THE AREA. IF HRRR ENDS
UP BEING RIGHT THERE COULD BE SOME DENSE FOG POSSIBLE IN THE FAR
EASTERN PORTION.
FOG AND STRATUS DECREASE LATE TONIGHT AND EARLY TOMORROW AS
SURFACE TROUGH MOVES THROUGH AND SHIFTS/INCREASES THE WINDS FROM
THE WEST. AT THIS TIME THE FOG SHOULD END BY MID MORNING. ONCE THE
FOG/CLOUDS CLEAR OFF THERE WILL BE PLENTIFUL SUNSHINE AND
DOWNSLOPE WINDS THROUGH 700 MB. COMBINATION OF DRY AIR MASS AND
GROUND COMBINED WITH THE ABUNDANT SUNSHINE AND DOWNSLOPE WINDS
WILL ALLOW FOR A GOOD WARMUP.
QUESTION IS HOW MUCH. THE NWP AND ESPECIALLY THE 2 METER GUIDANCE
HAS BEEN RUNNING COOL DURING THE LAST WEEK. AT THIS TIME WENT
ABOVE GUIDANCE IN MOST PLACES WITH 60S...MOSTLY MIDDLE AND UPPER
60S....ACROSS THE ENTIRE AREA.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 210 PM MST FRI NOV 21 2014
FOR THE EXTENDED FORECAST PERIOD...VARIABLE WEATHER CONDITIONS ARE
EXPECTED THROUGHOUT DUE TO PASSING COLD FRONTS UNDER A NORTHWEST
FLOW REGIME. OVERALL...THE PATTERN REMAINS FAIRLY CONSISTENT WITH
LITTLE CHANCE OF MAJOR PRECIPITATION-PRODUCING SYSTEMS REACHING THE
REGION. PRIMARY CHANGE TO THIS EXTENDED PACKAGE WAS TO REMOVE
PRECIPITATION CHANCES FOR THANKSGIVING. MORE DETAILS ON THIS BELOW.
FOR SATURDAY NIGHT INTO SUNDAY MORNING...A STRONG COLD FRONT PASSAGE
IS ANTICIPATED. TEMPERATURES WILL BE SLOW TO FALL SATURDAY NIGHT DUE
TO INCREASING CLOUD COVER. THEN...A QUICK DROP IN TEMPERATURES AND
GUSTY NORTH WINDS ARE LIKELY IMMEDIATELY BEHIND THE FRONT. AS THE
FRONT PASSES THROUGH...THE ATMOSPHERE MOISTENS AT LOW LEVELS WHEN
THE COOLER AIR INTRUDES. THERE SHOULD BE ENOUGH MID-LEVEL LIFT AND
MOISTURE FOR RAIN/SNOW SHOWERS DEVELOPMENT BUT THE QUESTION OVER THE
PAST FEW FORECAST RUNS HAS BEEN WHETHER OR NOT THIS PRECIPITATION
REACHES THE GROUND. BASED ON LATEST GUIDANCE...THERE SHOULD BE A
SMALL WINDOW OF OPPORTUNITY FOR MEASURABLE PRECIPITATION TO REACH
THE GROUND AHEAD OF INCOMING POST-FRONTAL DRY AIR. THEREFORE...
PLACED A SLIGHT CHANCE FOR MEASURABLE PRECIPITATION INTO THE
FORECAST AND MAINTAINED SPRINKLES/FLURRIES MENTION SURROUNDING THE
SLIGHT CHANCE POPS.
MAIN STORY FOR THE REST OF SUNDAY THROUGH MONDAY SHOULD BE
BREEZY/WINDY CONDITIONS AND COOL TEMPERATURES. WITH PERSISTENT COLD
AIR ADVECTION AND POSSIBLE CLOUD COVER OVERHEAD...HAVE A HARD TIME
BELIEVING THAT THE REGION WILL BE ABLE TO REACH MEX/MET/ECE GUIDANCE
TEMPERATURES. WENT BELOW GUIDANCE FOR HIGH TEMPERATURES DUE TO THIS
THINKING. REGARDING THE WINDS...MODELS ARE NOT IN STRONG AGREEMENT
WITH RESPECT TO HOW STRONG THE WINDS WILL BE AND WHEN THE STRONGEST
WINDS WILL OCCUR. ANY POSSIBLE CLOUD COVER ALSO MESSES WITH
ANTICIPATED MIXING HEIGHTS SO HARD TO TELL HOW STRONG THE MIXED DOWN
GUSTS WILL BE AT THIS TIME. WITHOUT A STRONG CUT-OFF LOW PRESSURE
SYSTEM PRESENT...CURRENTLY DO NOT BELIEVE THAT THIS WILL BE A MAJOR
WIND EVENT. TYPICAL COLD/WINDY HIGH PLAINS DAYS ARE FORECAST WITH
NORTH WINDS 20-30 MPH...GUSTING TO 45 MPH AND HIGH TEMPERATURES IN
THE LOW TO UPPER 40S.
BEYOND MONDAY...A WEAK UPPER LEVEL DISTURBANCE MOVES THROUGH THE
HIGH PLAINS TUESDAY INTO TUESDAY NIGHT. THE CR INITIALIZATION
PROCEDURE DID NOT INCLUDE POPS AND WITH A DRY LAYER OF AIR AT THE
SURFACE...THOUGHT THIS WAS APPROPRIATE. POPS MAY NEED TO BE INCLUDED
AT A LATER TIME BUT MODEL CONSISTENCY WAS NOT STRONG ENOUGH FOR
INCLUSION WITH THIS RUN.
ANOTHER STRONG UPPER LEVEL DISTURBANCE SWINGS SOUTH OVER THE PLAINS
AND INTO THE MID-MISSISSIPPI VALLEY BY THURSDAY. THIS SYSTEM SHOULD
FORCE A BACKDOOR COLD FRONT INTO THE HIGH PLAINS. IT IS HARD TO TELL
HOW FAR SOUTHWEST THIS FRONT WILL REACH AND THERE IS A STRONG CHANCE
FOR A LARGE TEMPERATURE GRADIENT ACROSS THE REGION. CURRENT
THANKSGIVING FORECAST CALLS FOR A HIGH OF 38 DEGREES AT MCCOOK
NEBRASKA...44 AT GOODLAND KANSAS AND 52 AT KIT CARSON COLORADO.
MODELS TRENDED PRECIPITATION CHANCES FOR THANKSGIVING DOWN AND
BELIEVE THIS IS ACCURATE CONSIDERING A RIDGE OF HIGH PRESSURE WILL
BUILD IN FROM THE WEST.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 433 PM MST FRI NOV 21 2014
KGLD WILL SEE VFR CONDITIONS THROUGH THE FORECAST PERIOD WITH A
MIX OF SKC-SCT150. WINDS SSW AROUND 10KTS.
KMCK WILL SEE MOSTLY VFR CONDITIONS WITH A MIX OF SKC AND
SCT150-250. BKN020 IS POSSIBLE FROM 02Z-04Z SAT. WINDS SOUTH
AROUND 10KTS...BECOMING WSW AROUND 10KTS BY 06Z SAT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...JN
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1041 AM MST THU NOV 20 2014
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 201 AM MST THU NOV 20 2014
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS CONTINUE TO
SHOW PERSISTENT LARGE SCALE TROUGH IN PLACE OVER THE EASTERN US
WITH AMPLIFIED RIDGE EXTENDING FROM THE GREAT BASIN INTO THE
CANADIAN ROCKIES. NW FLOW IS IN PLACE OVER THE CWA...WITH A
DRY/SUBSIDENT LAYER IN PLACE OVER OUR CWA. AT THE SURFACE A
STATIONARY FRONT CURRENTLY BISECTS OUR CWA FROM SW NEBRASKA AND
INTO SOUTH CENTRAL KANSAS. WEAK LEE TROUGH IS IN PLACE OVER
EASTERN COLORADO WITH SURFACE HIGH PRESSURE OVER THE NORTHERN
PLAINS INTO THE CENTRAL MISSISSIPPI RIVER VALLEY.
AMPLIFIED PATTERN BEGINS TO BREAK DOWN TONIGHT WITH ZONAL FLOW
EXPECTED THROUGH THIS WEEKEND. A SHORTWAVE TROUGH WILL PASS
THROUGH THE SOUTHERN PLAINS FRIDAY AND FRIDAY NIGHT BECOMING
NEGATIVELY TILTED AND DEEPENING AS IT MOVES TOWARDS THE
MISSISSIPPI RIVER VALLEY. GOOD MOISTURE ADVECTION AHEAD OF THIS
FEATURE WILL HELP BRING INCREASING TD VALUES AS FAR NORTH AS THE
EASTERN PART OF OUR CWA BY TONIGHT WITH A SHALLOW MOIST LAYER
POSSIBLY SUPPORTING FREEZING FOG DEVELOPMENT. BEST MOISTURE
ADVECTION WILL BE FURTHER EAST AND WITH SW WINDS POSSIBLY
BRINGING DRIER AIR IN FROM THE WEST BE MAY NOT SEE MUCH POTENTIAL
FOR A ADVECTION FOG EVENT FROM DOWNSTREAM SOURCES...EXCEPT FOR
MAYBE THE FAR EASTERN PART OF THE CWA. BL WINDS INCREASE TO THE
15-22KT RANGE...AND WE COULD SEE LOW LEVEL MOISTURE MIX OUT AS A
HEAVY FROST OR A LOW STRATUS LAYER ESTABLISH ITSELF. WE ALSO HAVE
INCREASING/THICKENING CIRRUS...WHICH COULD LIMIT RADIATIONAL
COOLING. I KEPT PATCHY FREEZING FOG MENTION IN PLACE...BUT
CONFIDENCE IS NOT HIGH.
WESTERLY CROSS MOUNTAIN FLOW WILL SUPPORT GOOD WAA OVER OUR CWA
SATURDAY...WITH ABOVE NORMAL TEMPERATURES IN THE LOWER 60S. LARGE
SCALE TROUGHING WILL BEGIN TO REESTABLISH ITSELF OVER THE PLAINS
SATURDAY NIGHT. MODELS SHOWING LITTLE CONSISTENCY IN LOCATION OF
WEAK PRECIP SIGNAL AND TREND IS FOR BEST FORCING/MOISTURE TO
SPLIT AROUND OUR CWA. I COULDNT COMPLETELY RULE OUT A FEW FLURRIES
OR A LIGHT SNOW SHOWER OVER PARTS OF OUR CWA...BUT CONFIDENCE WAS
TOO LOW TO ADD MENTION IN FORECAST AT THIS POINT.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 201 AM MST THU NOV 20 2014
SUNDAY...UPPER TROUGH AXIS AND QUITE A BIT OF CLOUDINESS
MOVE ACROSS THE AREA DURING THE DAY. WILL ALSO HAVE TO CONTEND WITH
WINDY NORTHWEST WINDS. MOISTURE REMAINS LIMITED AT LOW LEVELS THUS
NO PRECIPITATION EXPECTED WITH THE TROUGH PASSAGE. GFS/ECMWF 850MB
TEMPERATURES SUPPORT AFTERNOON HIGHS IN THE IN THE MID 40S TO AROUND
50 IN FAR EASTERN COLORADO...LOW 50S EAST OF THE STATE LINE. FOR
SUNDAY NIGHT GENERAL TREND IS FOR DECREASING CLOUDINESS FROM WEST TO
EAST WITH CENTER OF UPPER LOW DIVING SOUTHEAST INTO THE NORTH
CENTRAL PART OF THE COUNTRY. THIS WILL ALLOW COLDER AIR ALOFT TO
MOVE IN FROM THE NORTHEAST. WITH SFC WINDS REMAINING FROM THE
WEST/NORTHWEST AT 10 TO 20 MPH ATMOSPHERE SHOULD REMAIN WELL MIXED
AND AS A RESULT OVERNIGHT LOWS WILL BE NEAR NORMAL IN THE UPPER
TEENS TO UPPER 20S (WEST TO EAST).
MONDAY...UPPER LOW ROTATES SLOWLY EAST TOWARD THE GREAT LAKES DURING
THE DAY LIFTING SLOWLY NORTHEAST TOWARD THE UPPER GREAT LAKES
OVERNIGHT. WE WILL CONTINUE TO SEE VARYING DEGREES OF CLOUDINESS
THROUGH MONDAY NIGHT AND AGAIN NO PRECIPITATION EXPECTED. ITS
LOOKING LIKE ANOTHER RATHER WINDY DAY WITH NORTHWEST WINDS GUSTING
35 TO POSSIBLY 40 MPH. WINDS DROP OFF MONDAY NIGHT WITH 10 TO 15 MPH
EXPECTED. HIGH TEMPERATURES IN THE UPPER 30S TO LOW 40S IN FAR
EASTERN COLORADO...MID TO POSSIBLY UPPER 40S EAST OF THE STATE LINE.
COULD BE COOLER IF THE ECMWF 850MB TEMPERATURES VERIFY. LOWS AGAIN
MID TEENS TO MID 20S (WEST TO EAST).
TUESDAY...FORECAST AREA REMAINS UNDER NORTHWEST FLOW BUT 500 HEIGHTS
START TO RISE AS EAST COAST TROUGH STARTS TO MOVE AWAY AND LOSE ITS
INFLUENCE OVER THE AREA WHILE TO THE WEST CENTER OF UPPER RIDGE
STARTS TO REACH THE CALIFORNIA COAST. ALONG WITH RISING UPPER
HEIGHTS ARE WARMING 850MB TEMPERATURES PER ECMWF WHILE THE GFS
ACTUALLY HAS SLIGHTLY LOWER 850MB TEMPS COMPARED TO MONDAY.
BASICALLY A STALEMATE AT PRESENT AND ITS REFLECTED IN AFTERNOON
TEMPERATURES WHICH NEARLY MIRROR MONDAYS. MID AND UPPER CLOUDINESS
MOVE IN FROM THE WEST LATE IN THE DAY CONTINUING SLOWLY EAST DURING
THE NIGHT. NO PRECIPITATION EXPECTED. LOWS TUESDAY NIGHT SEASONAL
WITH UPPER TEENS TO LOW 20S.
WEDNESDAY...PRETTY BIG DISPARITIES BETWEEN LONG RANGE MODELS WITH
THE GFS WARMING TEMPERATURES (PER 850 TEMPS) WELL INTO THE 60S WHILE
THE ECMWF HAS READINGS MUCH COOLER. GFS HAS RISING HEIGHTS WITH
NORTHWEST FLOW ALOFT WHILE THE ECMWF SHOWS UPPER TROUGH DEVELOPING
ACROSS THE GREAT BASIN. NO CHANGES/TWEAKS MADE DURING THIS TIMEFRAME
AND WILL GO WITH HIGHS IN THE 50S AND LOWS IN THE MID 20S TO LOW 30S
UNDER VARIABLE CLOUDINESS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1036 AM MST THU NOV 20 2014
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. LIGHT AND VARIABLE
WINDS WILL SHIFT TOWARD THE SOUTH FROM LATER THIS AFTERNOON INTO
TONIGHT. MODELS ARE INDICATING AN INCREASE OF BOUNDARY LAYER
RELATIVE HUMIDITY LATER TONIGHT. HOWEVER...MODELS DISAGREE WITH
THE AMOUNT AND WHERE TO EXACTLY PUT IT.
AT THIS TIME THE BRUNT OF THE INCREASE AND THE RESULTING STRATUS
AND FOG LOOK TO BE TO THE EAST OF BOTH SITES WITH KMCK HAVING THE
BEST CHANCE OF SEE A SCATTERED LOW DECK. THE THICKER HIGHER LEVEL
CLOUD COVER MOVING IN DURING THIS TIME LOOKS TO LIMIT THE AMOUNT
OF STRATUS AND FOG AS WELL. LOOKS TO BE ENOUGH MOISTURE THAT KMCK
MAY SEE SOME MINOR REDUCTIONS IN VISIBILITY BY LATER TONIGHT
THROUGH MID MORNING TOMORROW.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
423 AM MST THU NOV 20 2014
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 201 AM MST THU NOV 20 2014
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS CONTINUE TO
SHOW PERSISTENT LARGE SCALE TROUGH IN PLACE OVER THE EASTERN US
WITH AMPLIFIED RIDGE EXTENDING FROM THE GREAT BASIN INTO THE
CANADIAN ROCKIES. NW FLOW IS IN PLACE OVER THE CWA...WITH A
DRY/SUBSIDENT LAYER IN PLACE OVER OUR CWA. AT THE SURFACE A
STATIONARY FRONT CURRENTLY BISECTS OUR CWA FROM SW NEBRASKA AND
INTO SOUTH CENTRAL KANSAS. WEAK LEE TROUGH IS IN PLACE OVER
EASTERN COLORADO WITH SURFACE HIGH PRESSURE OVER THE NORTHERN
PLAINS INTO THE CENTRAL MISSISSIPPI RIVER VALLEY.
AMPLIFIED PATTERN BEGINS TO BREAK DOWN TONIGHT WITH ZONAL FLOW
EXPECTED THROUGH THIS WEEKEND. A SHORTWAVE TROUGH WILL PASS
THROUGH THE SOUTHERN PLAINS FRIDAY AND FRIDAY NIGHT BECOMING
NEGATIVELY TILTED AND DEEPENING AS IT MOVES TOWARDS THE
MISSISSIPPI RIVER VALLEY. GOOD MOISTURE ADVECTION AHEAD OF THIS
FEATURE WILL HELP BRING INCREASING TD VALUES AS FAR NORTH AS THE
EASTERN PART OF OUR CWA BY TONIGHT WITH A SHALLOW MOIST LAYER
POSSIBLY SUPPORTING FREEZING FOG DEVELOPMENT. BEST MOISTURE
ADVECTION WILL BE FURTHER EAST AND WITH SW WINDS POSSIBLY
BRINGING DRIER AIR IN FROM THE WEST BE MAY NOT SEE MUCH POTENTIAL
FOR A ADVECTION FOG EVENT FROM DOWNSTREAM SOURCES...EXCEPT FOR
MAYBE THE FAR EASTERN PART OF THE CWA. BL WINDS INCREASE TO THE
15-22KT RANGE...AND WE COULD SEE LOW LEVEL MOISTURE MIX OUT AS A
HEAVY FROST OR A LOW STRATUS LAYER ESTABLISH ITSELF. WE ALSO HAVE
INCREASING/THICKENING CIRRUS...WHICH COULD LIMIT RADIATIONAL
COOLING. I KEPT PATCHY FREEZING FOG MENTION IN PLACE...BUT
CONFIDENCE IS NOT HIGH.
WESTERLY CROSS MOUNTAIN FLOW WILL SUPPORT GOOD WAA OVER OUR CWA
SATURDAY...WITH ABOVE NORMAL TEMPERATURES IN THE LOWER 60S. LARGE
SCALE TROUGHING WILL BEGIN TO REESTABLISH ITSELF OVER THE PLAINS
SATURDAY NIGHT. MODELS SHOWING LITTLE CONSISTENCY IN LOCATION OF
WEAK PRECIP SIGNAL AND TREND IS FOR BEST FORCING/MOISTURE TO
SPLIT AROUND OUR CWA. I COULDNT COMPLETELY RULE OUT A FEW FLURRIES
OR A LIGHT SNOW SHOWER OVER PARTS OF OUR CWA...BUT CONFIDENCE WAS
TOO LOW TO ADD MENTION IN FORECAST AT THIS POINT.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 201 AM MST THU NOV 20 2014
SUNDAY...UPPER TROUGH AXIS AND QUITE A BIT OF CLOUDINESS
MOVE ACROSS THE AREA DURING THE DAY. WILL ALSO HAVE TO CONTEND WITH
WINDY NORTHWEST WINDS. MOISTURE REMAINS LIMITED AT LOW LEVELS THUS
NO PRECIPITATION EXPECTED WITH THE TROUGH PASSAGE. GFS/ECMWF 850MB
TEMPERATURES SUPPORT AFTERNOON HIGHS IN THE IN THE MID 40S TO AROUND
50 IN FAR EASTERN COLORADO...LOW 50S EAST OF THE STATE LINE. FOR
SUNDAY NIGHT GENERAL TREND IS FOR DECREASING CLOUDINESS FROM WEST TO
EAST WITH CENTER OF UPPER LOW DIVING SOUTHEAST INTO THE NORTH
CENTRAL PART OF THE COUNTRY. THIS WILL ALLOW COLDER AIR ALOFT TO
MOVE IN FROM THE NORTHEAST. WITH SFC WINDS REMAINING FROM THE
WEST/NORTHWEST AT 10 TO 20 MPH ATMOSPHERE SHOULD REMAIN WELL MIXED
AND AS A RESULT OVERNIGHT LOWS WILL BE NEAR NORMAL IN THE UPPER
TEENS TO UPPER 20S (WEST TO EAST).
MONDAY...UPPER LOW ROTATES SLOWLY EAST TOWARD THE GREAT LAKES DURING
THE DAY LIFTING SLOWLY NORTHEAST TOWARD THE UPPER GREAT LAKES
OVERNIGHT. WE WILL CONTINUE TO SEE VARYING DEGREES OF CLOUDINESS
THROUGH MONDAY NIGHT AND AGAIN NO PRECIPITATION EXPECTED. ITS
LOOKING LIKE ANOTHER RATHER WINDY DAY WITH NORTHWEST WINDS GUSTING
35 TO POSSIBLY 40 MPH. WINDS DROP OFF MONDAY NIGHT WITH 10 TO 15 MPH
EXPECTED. HIGH TEMPERATURES IN THE UPPER 30S TO LOW 40S IN FAR
EASTERN COLORADO...MID TO POSSIBLY UPPER 40S EAST OF THE STATE LINE.
COULD BE COOLER IF THE ECMWF 850MB TEMPERATURES VERIFY. LOWS AGAIN
MID TEENS TO MID 20S (WEST TO EAST).
TUESDAY...FORECAST AREA REMAINS UNDER NORTHWEST FLOW BUT 500 HEIGHTS
START TO RISE AS EAST COAST TROUGH STARTS TO MOVE AWAY AND LOSE ITS
INFLUENCE OVER THE AREA WHILE TO THE WEST CENTER OF UPPER RIDGE
STARTS TO REACH THE CALIFORNIA COAST. ALONG WITH RISING UPPER
HEIGHTS ARE WARMING 850MB TEMPERATURES PER ECMWF WHILE THE GFS
ACTUALLY HAS SLIGHTLY LOWER 850MB TEMPS COMPARED TO MONDAY.
BASICALLY A STALEMATE AT PRESENT AND ITS REFLECTED IN AFTERNOON
TEMPERATURES WHICH NEARLY MIRROR MONDAYS. MID AND UPPER CLOUDINESS
MOVE IN FROM THE WEST LATE IN THE DAY CONTINUING SLOWLY EAST DURING
THE NIGHT. NO PRECIPITATION EXPECTED. LOWS TUESDAY NIGHT SEASONAL
WITH UPPER TEENS TO LOW 20S.
WEDNESDAY...PRETTY BIG DISPARITIES BETWEEN LONG RANGE MODELS WITH
THE GFS WARMING TEMPERATURES (PER 850 TEMPS) WELL INTO THE 60S WHILE
THE ECMWF HAS READINGS MUCH COOLER. GFS HAS RISING HEIGHTS WITH
NORTHWEST FLOW ALOFT WHILE THE ECMWF SHOWS UPPER TROUGH DEVELOPING
ACROSS THE GREAT BASIN. NO CHANGES/TWEAKS MADE DURING THIS TIMEFRAME
AND WILL GO WITH HIGHS IN THE 50S AND LOWS IN THE MID 20S TO LOW 30S
UNDER VARIABLE CLOUDINESS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 423 AM MST THU NOV 20 2014
VFR CONDITIONS SHOULD PREVAIL AT BOTH KGLD AND KMCK THROUGH
09-10Z TONIGHT. WHILE FOG AND LOW STRATUS REMAIN POSSIBLE IN THE
10-12Z TIME PERIOD AS LOW LEVEL MOISTURE ADVECTS INTO THE
REGION...THERE IS ENOUGH UNCERTAINTY AT THIS RANGE DUE TO
POTENTIAL FOR WELL MIXED BL I DECIDED TO MAINTAIN VFR THROUGH THE
END OF THE TAF PERIOD. BETTER CHANCE FOR SUB VFR CONDITIONS
APPEARS TO BE AT KMCK WHERE BETTER LOW LEVEL MOISTURE WILL BE.
WINDS ARE EXPECTED TO REMAIN BELOW 12KT AT BOTH TAF SITES WITH
WINDS EVENTUALLY BACKING TO THE EAST SOUTHEAST BY TONIGHT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
202 AM MST THU NOV 20 2014
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 201 AM MST THU NOV 20 2014
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS CONTINUE TO
SHOW PERSISTENT LARGE SCALE TROUGH IN PLACE OVER THE EASTERN US
WITH AMPLIFIED RIDGE EXTENDING FROM THE GREAT BASIN INTO THE
CANADIAN ROCKIES. NW FLOW IS IN PLACE OVER THE CWA...WITH A
DRY/SUBSIDENT LAYER IN PLACE OVER OUR CWA. AT THE SURFACE A
STATIONARY FRONT CURRENTLY BISECTS OUR CWA FROM SW NEBRASKA AND
INTO SOUTH CENTRAL KANSAS. WEAK LEE TROUGH IS IN PLACE OVER
EASTERN COLORADO WITH SURFACE HIGH PRESSURE OVER THE NORTHERN
PLAINS INTO THE CENTRAL MISSISSIPPI RIVER VALLEY.
AMPLIFIED PATTERN BEGINS TO BREAK DOWN TONIGHT WITH ZONAL FLOW
EXPECTED THROUGH THIS WEEKEND. A SHORTWAVE TROUGH WILL PASS
THROUGH THE SOUTHERN PLAINS FRIDAY AND FRIDAY NIGHT BECOMING
NEGATIVELY TILTED AND DEEPENING AS IT MOVES TOWARDS THE
MISSISSIPPI RIVER VALLEY. GOOD MOISTURE ADVECTION AHEAD OF THIS
FEATURE WILL HELP BRING INCREASING TD VALUES AS FAR NORTH AS THE
EASTERN PART OF OUR CWA BY TONIGHT WITH A SHALLOW MOIST LAYER
POSSIBLY SUPPORTING FREEZING FOG DEVELOPMENT. BEST MOISTURE
ADVECTION WILL BE FURTHER EAST AND WITH SW WINDS POSSIBLY
BRINGING DRIER AIR IN FROM THE WEST BE MAY NOT SEE MUCH POTENTIAL
FOR A ADVECTION FOG EVENT FROM DOWNSTREAM SOURCES...EXCEPT FOR
MAYBE THE FAR EASTERN PART OF THE CWA. BL WINDS INCREASE TO THE
15-22KT RANGE...AND WE COULD SEE LOW LEVEL MOISTURE MIX OUT AS A
HEAVY FROST OR A LOW STRATUS LAYER ESTABLISH ITSELF. WE ALSO HAVE
INCREASING/THICKENING CIRRUS...WHICH COULD LIMIT RADIATIONAL
COOLING. I KEPT PATCHY FREEZING FOG MENTION IN PLACE...BUT
CONFIDENCE IS NOT HIGH.
WESTERLY CROSS MOUNTAIN FLOW WILL SUPPORT GOOD WAA OVER OUR CWA
SATURDAY...WITH ABOVE NORMAL TEMPERATURES IN THE LOWER 60S. LARGE
SCALE TROUGHING WILL BEGIN TO REESTABLISH ITSELF OVER THE PLAINS
SATURDAY NIGHT. MODELS SHOWING LITTLE CONSISTENCY IN LOCATION OF
WEAK PRECIP SIGNAL AND TREND IS FOR BEST FORCING/MOISTURE TO
SPLIT AROUND OUR CWA. I COULDNT COMPLETELY RULE OUT A FEW FLURRIES
OR A LIGHT SNOW SHOWER OVER PARTS OF OUR CWA...BUT CONFIDENCE WAS
TOO LOW TO ADD MENTION IN FORECAST AT THIS POINT.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 201 AM MST THU NOV 20 2014
SUNDAY...UPPER TROUGH AXIS AND QUITE A BIT OF CLOUDINESS
MOVE ACROSS THE AREA DURING THE DAY. WILL ALSO HAVE TO CONTEND WITH
WINDY NORTHWEST WINDS. MOISTURE REMAINS LIMITED AT LOW LEVELS THUS
NO PRECIPITATION EXPECTED WITH THE TROUGH PASSAGE. GFS/ECMWF 850MB
TEMPERATURES SUPPORT AFTERNOON HIGHS IN THE IN THE MID 40S TO AROUND
50 IN FAR EASTERN COLORADO...LOW 50S EAST OF THE STATE LINE. FOR
SUNDAY NIGHT GENERAL TREND IS FOR DECREASING CLOUDINESS FROM WEST TO
EAST WITH CENTER OF UPPER LOW DIVING SOUTHEAST INTO THE NORTH
CENTRAL PART OF THE COUNTRY. THIS WILL ALLOW COLDER AIR ALOFT TO
MOVE IN FROM THE NORTHEAST. WITH SFC WINDS REMAINING FROM THE
WEST/NORTHWEST AT 10 TO 20 MPH ATMOSPHERE SHOULD REMAIN WELL MIXED
AND AS A RESULT OVERNIGHT LOWS WILL BE NEAR NORMAL IN THE UPPER
TEENS TO UPPER 20S (WEST TO EAST).
MONDAY...UPPER LOW ROTATES SLOWLY EAST TOWARD THE GREAT LAKES DURING
THE DAY LIFTING SLOWLY NORTHEAST TOWARD THE UPPER GREAT LAKES
OVERNIGHT. WE WILL CONTINUE TO SEE VARYING DEGREES OF CLOUDINESS
THROUGH MONDAY NIGHT AND AGAIN NO PRECIPITATION EXPECTED. ITS
LOOKING LIKE ANOTHER RATHER WINDY DAY WITH NORTHWEST WINDS GUSTING
35 TO POSSIBLY 40 MPH. WINDS DROP OFF MONDAY NIGHT WITH 10 TO 15 MPH
EXPECTED. HIGH TEMPERATURES IN THE UPPER 30S TO LOW 40S IN FAR
EASTERN COLORADO...MID TO POSSIBLY UPPER 40S EAST OF THE STATE LINE.
COULD BE COOLER IF THE ECMWF 850MB TEMPERATURES VERIFY. LOWS AGAIN
MID TEENS TO MID 20S (WEST TO EAST).
TUESDAY...FORECAST AREA REMAINS UNDER NORTHWEST FLOW BUT 500 HEIGHTS
START TO RISE AS EAST COAST TROUGH STARTS TO MOVE AWAY AND LOSE ITS
INFLUENCE OVER THE AREA WHILE TO THE WEST CENTER OF UPPER RIDGE
STARTS TO REACH THE CALIFORNIA COAST. ALONG WITH RISING UPPER
HEIGHTS ARE WARMING 850MB TEMPERATURES PER ECMWF WHILE THE GFS
ACTUALLY HAS SLIGHTLY LOWER 850MB TEMPS COMPARED TO MONDAY.
BASICALLY A STALEMATE AT PRESENT AND ITS REFLECTED IN AFTERNOON
TEMPERATURES WHICH NEARLY MIRROR MONDAYS. MID AND UPPER CLOUDINESS
MOVE IN FROM THE WEST LATE IN THE DAY CONTINUING SLOWLY EAST DURING
THE NIGHT. NO PRECIPITATION EXPECTED. LOWS TUESDAY NIGHT SEASONAL
WITH UPPER TEENS TO LOW 20S.
WEDNESDAY...PRETTY BIG DISPARITIES BETWEEN LONG RANGE MODELS WITH
THE GFS WARMING TEMPERATURES (PER 850 TEMPS) WELL INTO THE 60S WHILE
THE ECMWF HAS READINGS MUCH COOLER. GFS HAS RISING HEIGHTS WITH
NORTHWEST FLOW ALOFT WHILE THE ECMWF SHOWS UPPER TROUGH DEVELOPING
ACROSS THE GREAT BASIN. NO CHANGES/TWEAKS MADE DURING THIS TIMEFRAME
AND WILL GO WITH HIGHS IN THE 50S AND LOWS IN THE MID 20S TO LOW 30S
UNDER VARIABLE CLOUDINESS.
&&
.AVIATION...(FOR TAFS 06Z THURSDAY THROUGH 06Z FRIDAY)
ISSUED AT 955 PM MST WED NOV 19 2014
VFR AT BOTH TAF SITES THROUGH THE PERIOD WITH MOSTLY SKC OVERNIGHT
AND INCREASING CIRRUS THURSDAY. SURFACE WINDS THROUGH THE PERIOD
WILL GENERALLY BE LIGHT AND VARIABLE BUT WITH A TENDENCY FOR SW
WINDS TONIGHT AT KGLD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...DLF
AREA FORECAST DISCUSSION
NWS CARIBOU ME
621 AM EST THU NOV 20 2014
.SYNOPSIS...
LOW PRESSURE WILL TRACK NORTH OF THE REGION THIS EVENING AND SEND
A COLD FRONT ACROSS THE AREA. A WEAK AREA OF LOW PRESSURE IN THE
GULF OF MAINE THIS MORNING WILL MOVE INTO THE MARITIMES THIS
EVENING. HIGH PRESSURE WILL BUILD SOUTH OF THE REGION FRIDAY AND
MOVE INTO THE ATLANTIC SATURDAY. LOW PRESSURE WILL PASS WELL WEST
OF THE REGION EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
621 AM EST UPDATE...NOT MUCH IN THE WAY OF SNOW SHOWING UP A WEAK
SECONDARY LOW DEVELOPED IN THE GULF OF MAINE EARLY THIS MORNING.
IT IS LOOKING LESS LIKELY THAT THERE WILL BE MUCH SNOWFALL THIS
MORNING. IN FACT THE HRRR AND RUC NOW HAVE LITTLE IN THE WAY OF
PRECIPITATION ALONG THE DOWN EAST COAST. A BAND OF SNOW SHOWERS
STILL EXPECTED TO DEVELOP LATE THIS AFTERNOON IN WESTERN MAINE AS
LAPSE RATES STEEPEN AHEAD OF AN ARCTIC COLD FRONT. MAIN UPDATE WAS
TO LOWER POPS ALONG THE COAST THIS MORNING AND TO BUMP UP THE POPS
A BIT IN THE NORTHEAST CORNER OF THE CWA WHERE THERE ARE SOME
LIGHT SNOW SHOWERS EARLY THIS MORNING.
PREVIOUS DISCUSSION...
LOW PRESSURE ALONG THE NORTH SHORE OF LAKE HURON EARLY THIS
MORNING WILL MOVE ACROSS SOUTHERN QUEBEC TODAY. THE LOW WILL PASS
NORTH OF MAINE THIS EVENING AND INTO THE NORTHERN GULF OF SAINT
LAWRENCE BY 12Z FRI. SOME OF THE ENERGY FROM THE MAIN LOW IS
TRANSFERRING TO THE MAINE COAST EARLY THIS MORNING. A VERY WEAK
WAVE OF LOW PRESSURE IN THE GULF OF MAINE ALONG A STRONG
BAROCLINICZONE WILL QUICKLY SCOOT OUT INTO THE WESTERN MARITIMES
THIS AFTERNOON. ANY SNOW ACROSS COASTAL HANCOCK AND CENTRAL AND
SOUTHERN WASHINGTON COUNTIES WILL COME TO AN END BY MID-LATE
MORNING. IT IS NOW LOOKING LESS IMPRESSIVE AND ANY ACCUMULATIONS
SHOULD MOSTLY BE AN INCH OR LESS. THERE IS STILL THE POSSIBILITY
OF UP TO 2 INCHES OF SNOW IN SOUTHEAST WASHINGTON COUNTY. IN THE
WAKE OF THE WAVE THERE WILL BE SOME CLEARING ACROSS THE DOWN EAST
REGION. IT WILL REMAIN MOSTLY CLOUDY ACROSS NORTHERN MAINE WITH A
COUPLE OF SNOW SHOWERS. AN ARCTIC COLD FRONT ASSOCIATED WITH THE
PARENT LOW WILL MOVE INTO WESTERN MAINE LATE THIS AFTERNOON AND
SWEEP ACROSS THE REMAINDER OF THE REGION THIS EVENING. THE FRONT
WILL BE ACCOMPANIED BY SCATTERED SNOW SHOWERS WITH THE POTENTIAL
FOR A HEAVIER SNOW SQUALL WHICH COULD LOCALLY PRODUCE POOR
VISIBILITY AND DROP AN INCH OF SNOW. STREAMERS ARE ALSO POSSIBLE
OFF THE ST LAWRENCE TONIGHT ACROSS NORTHERN MAINE...ESPECIALLY
DURING THE EVENING.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
AN UPPER TROUGH WILL SWING ACROSS THE REGION EARLY FRIDAY,
BRINGING A FEW SNOW SHOWERS OR FLURRIES TO NORTHERN MAINE, MAINLY
DURING THE MORNING HOURS. A VERY COLD DRY AIRMASS WILL FOLLOW AS
HIGH PRESSURE BUILDS INTO NEW ENGLAND. HIGHS ON FRIDAY WILL RANGE
FROM THE LOWER AND MID 20S NORTH TO THE LOWER 30S SOUTH. HOWEVER,
TEMPERATURES WILL FALL SHARPLY OVERNIGHT AS DECENT COLD AIR
ADVECTION SETS UP AHEAD OF THE APPROACHING HIGH. THE CENTER OF THE
HIGH WILL REMAIN TO OUR SOUTH, WHICH MEANS WINDS WILL LIKELY STAY
UP, LIMITING THE AMOUNT OF RADIATIONAL COOLING. EVEN STILL, FRIDAY
NIGHT WILL BE COLD, WITH LOWS IN THE NORTH IN THE SINGLE DIGITS.
CENTRAL AND SOUTHERN MAINE WILL GENERALLY BOTTOM OUT IN THE 10 TO
15 DEGREE RANGE, WITH THE COAST 15 TO 20.
FOR SATURDAY...THE HIGH SLIDES TO OUR SOUTH, RESULTING IN ZONAL FLOW
ACROSS THE REGION. WARM ADVECTION AROUND THE BACK OF THE HIGH WILL
ALLOW HIGH TEMPERATURES TO REACH A FEW DEGREES WARMER THAN THOSE ON
FRIDAY. THERE WILL BE SOME SNOW SHOWERS AROUND AS WELL, MAINLY FOR
THE NORTHERN PORTIONS OF OUR FORECAST AREA. ANY SNOW ACCUMULATION
WILL BE LESS THAN AN INCH.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
OUTSIDE OF SOME LIGHT SNOW SHOWERS SATURDAY NIGHT AND
SUNDAY...THE BIG STORY FOR THE EXTENDED PERIOD IS THE POTENTIAL
FOR A BIG WARMUP FOR THE FIRST HALF OF THE WORK WEEK. LOW PRESSURE
WILL DEVELOP OVER THE SOUTHERN PLAINS SATURDAY NIGHT AND THEN LIFT
NORTHWARD INTO THE GREAT LAKES BY MONDAY AFTERNOON. THIS WILL
ALLOW A STREAM OF WARMER AIR TO MOVE INTO THE EASTERN UNITED
STATES, ALONG WITH A WIDE SWATH OF WARM ADVECTION PRECIPITATION.
PRECIPITATION ASSOCIATED WITH THIS BROAD SYSTEM WILL BEGIN TO MOVE
INTO OUR REGION SUNDAY NIGHT, STARTING OUT AS SNOW BUT CHANGING
OVER TO RAIN FROM SOUTH TO NORTH. CAN`T TOTALLY RULE OUT SOME
MIXED PRECIPITATION DURING THE TRANSITION, BUT THERE`S TOO MUCH
UNCERTAINTY FOR THE DETAILS THIS FAR IN ADVANCE. REGARDLESS,
EXPECT WIDESPREAD RAIN SHOWERS ON MONDAY AS TEMPERATURES SOAR INTO
THE MID 40S TO MID 50S. WE`LL SEE SHOWERS CONTINUING RIGHT INTO
TUESDAY, WITH TEMPERATURES REMAINING WARM ENOUGH FOR RAIN, EVEN
MONDAY NIGHT. BY THE TIME THE COLDER AIR ARRIVES, EXPECT MUCH OF
THE PRECIPITATION TO BE DONE, WITH JUST SOME WRAP AROUND SNOW
SHOWERS POSSIBLE OVER OUR NORTH AND WEST.
&&
.AVIATION /11Z THURSDAY THROUGH MONDAY/...
NEAR TERM: ALL TAF SITES ARE VFR AS OF 6 AM...BUT WILL LOWER TO
MVFR AT TIMES THIS MORNING AT THE DOWN EAST TERMINALS. CEILINGS
SHOULD LOWER TO MVFR AT THE NORTHERN TERMINALS BY THIS AFTERNOON
WITH BRIEF IFR POSSIBLE IN ANY HEAVIER SNOW SHOWERS OF SQUALLS
LATE THIS AFTERNOON/EVENING.
SHORT TERM: MVFR CEILINGS ARE POSSIBLE AT THE NORTHERN SITES
THROUGH THE DAY FRIDAY AS AN UPPER TROUGH CROSSES THE REGION.
HOWEVER, SKIES WILL BECOME PARTLY TO MOSTLY CLEAR OVERNIGHT FRIDAY
NIGHT WITH VFR TO PREVAIL THROUGH SATURDAY MORNING. LOWER CEILINGS
AND VISIBILITIES RETURN FOR NORTHERN AREAS ON SATURDAY AND
SATURDAY NIGHT WITH MVFR CONDITIONS IN LIGHT SNOW. WE`LL SE A
RETURN TO VFR AT ALL SITES ON SUNDAY, BUT LOW PRESSURE MOVING
NORTHWARD WELL TO OUR WEST WILL BRING SNOW CHANGING OVER TO RAIN
SUNDAY NIGHT, WITH WIDESPREAD RAIN ON MONDAY. EXPECT PREVAILING
MVFR WITH IFR POSSIBLE SUNDAY NIGHT AND MONDAY.
&&
.MARINE...
NEAR TERM: THE SCA WAS EXTENDED THROUGH TONIGHT. A FEW GUSTS MAY
APPROACH 35 KNOTS LATE TONIGHT.
SHORT TERM: THE SMALL CRAFT WILL LIKELY NEED TO BE EXTENDED
THROUGH FRIDAY NIGHT AS WINDS AND WAVES WILL REMAIN ABOVE SCA
LEVELS DUE TO COLD AIR ADVECTION OVER THE RELATIVELY WARM WATERS.
IT LOOKS LIKE WINDS MAY APPROACH GALE CRITERIA, BUT WILL HOLD OFF
ON ANY GALE WATCHES AT THIS TIME AS IT LOOKS MARGINAL RIGHT NOW.
LATER SHIFTS MAY HAVE TO MAKE CHANGES TO THE CURRENT HEADLINES AS
WE DRAW NEARER TO THE WEEKEND.
&&
.EQUIPMENT...THE KCBW (HODGDON, MAINE) RADAR WENT DOWN AROUND 0100
EST THIS MORNING. THERE IS NO ESTIMATED TIME FOR RETURN TO
SERVICE.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST FRIDAY FOR ANZ050>052.
&&
$$
NEAR TERM...CB
SHORT TERM...HASTINGS
LONG TERM...HASTINGS
AVIATION...CB/HASTINGS
MARINE...CB/HASTINGS
EQUIPMENT...CB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
611 PM EST FRI NOV 21 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 406 PM EST FRI NOV 21 2014
WV IMAGERY AND RUC ANALYSIS INDICATED ZONAL MID/UPPER LEVEL FLOW
THROUGH THE NW AND N CNTRL CONUS WITH A WEAK SHORTWAVE TROUGH OVER
NORTH DAKOTA. A VIGOROUS SRN STREAM SHRTWV WAS SLIDING THROUGH SW
ARIZONA. AT THE SFC...SW FLOW WAS INCREASING FROM THE UPPER MS VALLEY
INTO THE NRN LAKES AS THE PRES GRADIENT TIGHTENS BETWEEN A 995 MB LOW
OVER MANITOBA AND 1034 MB HIGH OVER THE OH VALLEY. WAA INTO THE
REGION HAS BROUGHT AN INCREASE IN MID CLOUDS ACROSS UPPER MI WITH
ANOTHER BATCH UPSTREAM FROM MN INTO CNTRL WI. THE LOWER CLOUDS
REMAINED WELL TO THE SOUTH OVER MO AND SRN IA.
TONIGHT...EXPECT THAT THE STRONG SSW LOW LEVEL WAA PATTERN WILL
RAPIDLY BRING LOW LEVEL MOISTURE TOWARD THE AREA TO SUPPORT LOWER
CLOUDS INTO THE CWA. ALTHOUGH THE LOW LEVEL ISENTROPIC LIFT WILL BE
MARGINAL TO PRODUCE PCPN...UPSLOPE FLOW INTO MUCH OF THE AREA SHOULD
BE ENOUGH TO SUPPORT SOME LIGHT PCPN...ESPECIALLY OVER THE EAST HALF
WHERE ADDITIONAL MOISTURE FROM LAKE MICHIGAN IS AVAILABLE. MODEL
SOUNDINGS SUGGEST THAT THE 3K-8K DRY/WARM LAYER WILL BE STRONG ENOUGH
TO LIMIT/PREVENT ICE CRYSTAL AVAILABILITY INTO THE LOWER MOIST LAYER.
SO...EXPECT -FZDZ WILL BE THE PREDOMINANT PCPN TYPE. EVEN THOUGH
LITTLE IF ANY MEASURABLE PCPN IS EXPECTED...EVEN A VERY THIN COATING
OF -FZDZ COULD RESULT IN HAZARDOUS CONDITIONS ON UNTREATED ROADS.
SAT...THE COMBINATION OF DAYTIME HEATING AND ADDITIONAL WAA WILL
PUSH TEMPS ABOVE FREEZING IN MOST AREAS BY NOON CHANGING ANY
LINGERING FREEZING DRIZZLE TO DRIZZLE. EXPECT THE PCPN CHANCES TO
DIMINISH AS THE LOW LEVEL WAA WEAKENS DURING THE LATE MORNING AND
AFTERNOON. OTHERWISE...TEMPS SHOULD CLIMB TO READINGS AT OR ABOVE
NORMAL IN THE MID TO UPPER 30S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 430 PM EST FRI NOV 21 2014
A VERY ACTIVE WEEK IS IN STORE ACROSS THE UPPER GREAT LAKES AS A
POTENT MID-LEVEL SYSTEM DIGS INTO THE NORTHERN ROCKIES/PLAINS. THIS
WILL BRING A DECENT SURGE OF WARM AIR ACROSS THE AREA BY LATE
WEEKEND...BRINGING THE AREA BACK INTO ABOVE-AVERAGE TEMPERATURES FOR
A SHORT PERIOD. WITH THIS WILL COME A DECENT ROUND OF RAIN ACROSS
MAINLY CENTRAL AND EASTERN UPPER MI SUNDAY NIGHT INTO MONDAY. A
QUICK TRANSITION BACK TO WINTER WILL THEN TAKE PLACE ON MONDAY AS
THE TROUGH AND ASSOCIATED STRONG SURFACE LOW MOVE NORTHEAST OF THE
REGION...BRINGING STRONG CAA AND THE POTENTIAL FOR A DECENT SNOWFALL
ACROSS THE WESTERN CWA.
SATURDAY NIGHT...AS WEAK MID-LEVEL RIDGING WORKS ACROSS THE UPPER
GREAT LAKES...THIS LOOKS TO BE THE QUIETEST PERIOD THROUGH AT LEAST
TUESDAY. SIGNIFICANTLY DRY AIR ABOVE 900 HPA AND THE LACK OF ANY
APPRECIABLE MID/UPPER-LEVEL FORCING SHOULD LIMIT ANY DEEPER PRECIP
POTENTIAL. THE ONLY CONCERN IS A CHANCE FOR DZ/FZDZ ASSOCIATED WITH
WEAK LOW-LEVEL WAA SOUTH LATE IN THE NIGHT.
SUNDAY AND MONDAY...SIGNIFICANT CHANGES ARE SET TO BEGIN SUNDAY AS
AN ACTIVE NORTHERN AND SOUTHERN STREAM TAKE AIM ON THE UPPER GREAT
LAKES. FIRST...A LOOK AT THE LARGE SCALE PICTURE. AS THE
AFOREMENTIONED TROUGH OVER THE NORTHERN ROCKIES TRACKS ESE TOWARD
THE UPPER MS VALLEY...ANOTHER TROUGH ACROSS TX SATURDAY EVENING WILL
EJECT NE INTO THE UPPER GREAT LAKES. THE MERGING PIECES OF ENERGY
COMBINED WITH A QUICKLY DEVELOPING 120KT UPPER JET STREAK WILL
INDUCE A SFC LOW SOMEWHERE FROM EASTERN UPPER MI TO NORTHERN LOWER
MI BY 12Z MONDAY.
UPPER MI FINDS ITSELF CAUGHT IN A CONVOLUTED PATTERN SUNDAY MORNING
BEFORE THE TWO SYSTEMS CONSOLIDATE OVER THE AREA. OVERALL SYNOPTIC
FORCING REMAINS LIMITED TO START THE DAY...BUT LOW-LEVEL MOISTURE
TRANSPORT RESULTING IN A DEEPENING MOIST LAYER WILL ALLOW FOR
INCREASING CHANCES OF FZDZ/DZ IN THE MORNING...AND RAIN THROUGHOUT
THE AFTERNOON. BEST CHANCES DURING THE DAY LOOK TO BE ACROSS THE
CENTRAL AND EASTERN CWA WITH UPSLOPE AND MOISTURE INFLUENCES FROM SE
WINDS OFF LAKE MI. TEMPS THROUGH THE MOIST LAYER WILL REMAIN WARM
ENOUGH FOR SUPER-COOLED LIQUID...INTRODUCING CONTINUED CONCERN FOR
FZDZ/FZRA IN THE MORNING. GIVEN OUR RECENT SUB-FREEZING
STRETCH...CLEARED ROADS MAY SEE SOME ICING EVEN AS TEMPS WARM INTO
THE 30S TO LOW 40S DURING THE DAY SUNDAY. LATEST MDOT ROAD SENSORS
ARE SHOWING SUB-FREEZING TEMPS DOWN AT LEAST 24 INCHES BELOW THE
ROAD AND SUB-20F TEMPS DOWN TO AT LEAST 6 INCHES FOR NEARLY ALL
UPPER MI HIGHWAYS. WILL THEREFORE EXTEND THE FZDZ/FZRA POTENTIAL
THROUGH SUNDAY MORNING UNTIL AIR TEMPS WARM WELL-ABOVE FREEZING
SUNDAY AFTERNOON.
SIGNIFICANT MOISTURE TRANSPORT/ISENTROPIC LIFT WILL FOCUS ACROSS THE
EAST HALF OF THE CWA LATE SUNDAY AFTERNOON THROUGH MUCH OF THE
NIGHT. MEANWHILE...DECENT LIFT UNDER THE RIGHT ENTRANCE OF THE UPPER
JET WILL SPREAD ACROSS THE AREA. THIS SHOULD BRING WIDESPREAD PRECIP
OVER THE ENTIRE CWA THROUGHOUT THE NIGHT. WARMING TEMPS THROUGHOUT
THE COLUMN WILL RESULT IN A PTYPE OF ALL RAIN FOR THE ENTIRE CWA
SUNDAY AFTERNOON AND EVENING...AND ALL BUT THE WESTERN CWA LATE
SUNDAY NIGHT. WITH THE DECENT FORCING AND SUFFICIENT
MOISTURE...RAINFALL AMOUNTS LATE SUNDAY AFTERNOON THROUGH MONDAY
MORNING ARE EXPECTED TO SURPASS 0.75IN ACROSS THE EAST HALF. THIS
MAY BE A LITTLE CONSERVATIVE...BUT WOULD LIKE TO SEE BETTER
MID-LEVEL SUPPORT IN CONJUNCTION WITH THE UPPER JET BEFORE
INCREASING PRECIP AMOUNTS ANY FURTHER.
LATE SUNDAY NIGHT INTO MONDAY STARTS THE TRANSITION BACK TO SNOW AS
THE SFC LOW REACHES EASTERN UPPER MI LATE SUNDAY NIGHT. AS THE
SOUTHERN AND NORTHERN STREAM MERGE...THE NEW DEEPER TROUGH NEARLY
STALLS OVER THE UPPER GREAT LAKES. AN IMPRESSIVE 140KT UPPER JET
OVER THE MID MS VALLEY COMBINED WITH THE DEPARTING 120KT JET MOVING
OVER QUEBEC WILL BE ENOUGH TO KEEP A DEEPER SFC LOW OVER
ONTARIO/QUEBEC. MEANWHILE...A COMPACT TROUGH NEAR SEATTLE SUNDAY
AFTERNOON WILL DIG INTO THE DEPARTING THE TROUGH...FURTHER SLOWING
ITS MOVEMENT. ALL OF THIS COMES TOGETHER TO PRODUCE A LAGGING
LOW-LEVEL TROUGH AND DEFORMATION ZONE OVER UPPER MI ON MONDAY AND
MONDAY NIGHT. WITH LAKE ENHANCEMENT KICKING IN WITH N/NNW
WINDS...THERE IS INCREASING POTENTIAL FOR MODERATE TO POSSIBLY HEAVY
SNOW ACROSS THE NORTHWEST HALF OF UPPER MI. THE 12Z NAM AND 12Z GFS
HAVE BOTH COME IN WITH MUCH HIGHER QPF ACROSS THE WESTERN AND
CENTRAL CWA ON MONDAY. THOUGH THE ECMWF TAKES THE LOW ACROSS
NORTHERN LOWER MI...THE MID/UPPER-LEVEL SUPPORT PAINTS HIGHER QPF
AMOUNTS ACROSS THE WESTERN CWA AS WELL. THE TRANSITION TO SNOW
SHOULD BE UNDERWAY ACROSS THE FAR WEST BY DAYBREAK MONDAY...THEN
CONTINUE PRESSING EASTWARD. BY EARLY AFTERNOON...ALL BUT SOME OF THE
SHORELINE LOCATIONS OF THE WEST HALF SHOULD CHANGE OVER TO SNOW.
WHILE THERE IS SOME UNCERTAINTY IN HOW QUICK SNOW RATIOS INCREASE
DURING THE DAY...SEVERAL INCHES OF SNOW SHOULD FALL FOR MOST OF THE
NW HALF OF THE CWA MONDAY AFTERNOON. DO NOT WANT TO COMPLETELY JUMP
ON BOARD WITH THE NEW GUIDANCE QUITE YET...BUT THERE IS ENOUGH
EVIDENCE TO AT LEAST INCREASE SNOW AMOUNTS A BIT. THE EASTERN CWA
SHOULD SEE AT LEAST SOME ACCUMULATIONS...BUT A LATER TRANSITION TO
ALL SNOW COMBINED WITH A LESS FAVORABLE LOCATION OF THE FORCING WILL
KEEP AMOUNTS LOWER. WILL NEED TO MONITOR THIS OVER THE NEXT COUPLE
DAYS AS AT LEAST SOME WINTER WX HEADLINES MAY BE NEEDED.
MONDAY NIGHT AND TUESDAY...MOISTURE CONTINUING TO WRAP AROUND
THE BACKSIDE OF THE DEPARTING LOW COMBINED WITH UPSLOPE AND LAKE
INFLUENCE WILL GENERATE SNOW FOR THE N TO NNW WIND SNOW BELTS.
ANOTHER SEVERAL INCHES OF SNOW WILL BE POSSIBLE MONDAY NIGHT. BY
TUESDAY...SOME DRIER AIR WILL BEGIN TO WORK IN FROM THE WEST AS
INVERSION HEIGHTS FALL BELOW 5KFT...CUTTING OFF MUCH OF THE RESIDUAL
LAKE EFFECT PRECIP.
WEDNESDAY THROUGH FRIDAY...ANOTHER TROUGH DIGGING OUT OF
NORTH-CENTRAL CANADA WILL MOVE SE ACROSS THE UPPER GREAT LAKES
TUESDAY NIGHT INTO WEDNESDAY. ACCUMULATING SNOW WILL BE POSSIBLE
WEDNESDAY WITH THIS SYSTEM...BUT ITS TRACK AND STRENGTH ARE TOO
VARIABLE IN THE MODELS TO PIN DOWN LOCATIONS AT THIS TIME. MUCH
COLDER AIR ARRIVES BEHIND THE LOW AND INDUCES LES FOR THE NNW WIND
SNOW BELTS WEDNESDAY NIGHT THROUGH THANKSGIVING. A SLOWLY MODERATING
850 HPA AIRMASS WITH TEMPS -15 TO -20C WILL RESULT IN THE WEATHER
FEELING MORE LIKE CHRISTMAS THAN THANKSGIVING AS HIGHS STRUGGLE TO
GET OUT OF THE TEENS FOR AT LEAST THE WEST AND CENTRAL. BY
FRIDAY...ANOTHER PATTERN CHANGE WILL BRING MODERATING CONDITIONS TO
END THE WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 610 PM EST FRI NOV 21 2014
LLWS IS EXPECTED AS THE LOW LEVEL JET REALLY INCREASES 1-2KFT ABOVE
THE SURFACE...ESPECIALLY AT KSAW. HAVE LEFT GUSTS UP TO ACCOUNT FOR
THIS. MVFR CLOUDS WILL BE PUSHING NORTH-NORTHEAST INTO THE AREA
TONIGHT. THIS WILL LEAD TO A QUICK DROP IN CEILINGS LATE
TONIGHT...WITH KSAW HAVING THE LOWEST VALUES THAT SHOULD FALL INTO
THE IFR RANGE LATE. WITH THESE LOW CLOUDS...THERE IS THE POTENTIAL
FOR LIGHT FREEZING DRIZZLE LATE TONIGHT...ESPECIALLY AT KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 406 PM EST FRI NOV 21 2014
WINDS WILL CONTINUE TO INCREASE WITH A TIGHT PRES GRADIENT BETWEEN
LOW PRES OVER THE PLAINS AND A RIDGE OVER THE OH VALLEY.
WINDS TOT 30KTS WITH FREQUENT GALE FORCE GUSTS TO 35 KNOTS ARE
EXPECTED TONIGHT. THE PRESSURE GRADIENT WILL DECREASE SATURDAY INTO
SATURDAY NIGHT AS A TROUGH TRAILING THE CANADIAN LOW DROPS SOUTHEAST
OVER LAKE SUPERIOR. A DEVELOPING LOW IN THE CENTRAL/SOUTHERN PLAINS
ON SATURDAY NIGHT WILL LIFT NORTHEAST THROUGH THE GREAT LAKES REGION
TO NEAR THE STRAITS MONDAY MORNING AT AROUND 28.9 INCHES. AS THE LOW
LIFTS TO THE NORTHEAST ON MONDAY NORTHERLY GALES ARE LIKELY WHICH
COULD PERSIST THROUGH MONDAY NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 AM EST SATURDAY FOR LSZ266-267.
GALE WARNING UNTIL 7 AM EST /6 AM CST/ SATURDAY FOR LSZ162-263-
264.
LAKE MICHIGAN...
GALE WARNING UNTIL 10 AM EST SATURDAY FOR LMZ248.
&&
$$
SHORT TERM...JLB
LONG TERM...KLUBER
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
856 PM CST FRI NOV 21 2014
.UPDATE...
EVENING WV/UPPER AIR ANALYSIS INDICATES THE REGION SITUATED
BETWEEN AN H5 UPPER RIDGE TO THE E AND STRENGTHENING S/WV OVER THE
SW CONUS/NRN MEXICO. SFC ANALYSIS INDICATES 1035MB SFC HIGH OVER THE
APPALACHIANS AND A LOW PRESSURE DEVELOPING IN SRN OK/NRN TX. FOR
TONIGHT...THESE MID/HIGH CLOUDS WILL GRADUALLY MOVE TO THE N BEFORE
FILLING IN AFTER 12Z TONIGHT. DUE TO SOME GRADUAL INCREASING
ISENTROPIC LIFT/MOISTURE TRANSPORT AND ASSOCIATED LIGHT RAIN...SLIGHTLY
SHIFTED SLIGHT CHANCE POPS A TOUCH TO THE E. HRRR INDICATES THIS
ACTIVITY WILL GRADUALLY SHIFT BACK TO THE W AND WEAKEN TONIGHT DUE TO
WEAKENING MOISTURE TRANSPORT ON 315K THETA SFC. DUE TO SOME OF THE
CLOUD COVER...WENT SLIGHTLY WARMER IN THE NW WHILE A TOUCH COOLER IN
THE E DUE TO CLEAR SKIES LONGER. ADJUSTED HOURLY TEMPS/DEWPOINTS TO
CURRENT TRENDS. REST OF THE FORECAST IS ON TRACK. /DC/
&&
.AVIATION...VFR CEILINGS WILL CONTINUE AT ALL TAF SITES THROUGH THE
PERIOD WITH NO RESTRICTIONS TO VISIBILITY. WINDS WILL REMAIN FROM
THE SOUTHEAST AT 5 TO 10 KNOTS. /26/
&&
.PREV DISCUSSION... /ISSUED 328 PM CST FRI NOV 21 2014/
SHORT TERM...TONIGHT THROUGH MONDAY...PARTLY TO MOSTLY CLOUDY
CONDITIONS CAN BE EXPECTED TONIGHT AND SATURDAY. A FEW SHOWERS ARE
POSSIBLE GENERALLY WEST OF THE MISSISSIPPI RIVER BOTH PERIODS.
A PERIOD OF RAPID CHANGE IN THE ATMOSPHERE WILL BEGIN SATURDAY NIGHT
AS A POTENT SYSTEM PULLS OUT OF THE SOUTHWEST STATES ACROSS TEXAS.
THE UPPER SYSTEM WILL MOVE ACROSS OUR REGION THE FIRST HALF OF SUNDAY.
MOISTURE WILL SURGE NORTHWARD RAPIDLY SATURDAY NIGHT ESPECIALLY THE
LATTER HALF OF THE NIGHT. SCATTERED SHOWERS EARLY SHOULD INCREASE TO
WIDESPREAD SHOWERS WITH SOME THUNDERSTORMS LATE SATURDAY NIGHT. MOST OF
THIS ACTIVITY SHOULD BE ELEVATED IN NATURE SATURDAY NIGHT EXCEPT FOR
THE FAR SOUTHERN PORTIONS OF THE AREA WHERE DEWPOINTS WILL BE
GETTING INTO THE MID 60S BY DAYBREAK SUNDAY.
THERE REMAINS CONSIDERABLE SPREAD IN THE MODEL SOLUTIONS.
HOWEVER...MOST GENERALLY DEVELOP AN ORGANIZED QLCS TYPE CONVECTIVE
SYSTEM ACROSS CENTRAL LOUISIANA AND MOVE IT RAPIDLY NORTHEAST ACROSS
SOUTHERN MISSISSIPPI AND SOUTHEAST LOUISIANA SUNDAY MORNING. EXPECT THE
MARINE LAYER TO SURGE NORTH ALONG AND EAST OF THE QLCS WHICH WILL
INCREASE THE INSTABILITY WITH THIS AREA OF STORMS. STRONG LOW AND MID
LEVEL FLOW AND AN IMPRESSIVE MID LEVEL DRY PUNCH SHOULD CONTRIBUTE TO
THE ORGANIZATION OF THE QLCS. CURRENT THINKING IS THAT THE HIGHEST
CHANCE OF SEVERE STORMS WILL BE FROM ABOUT NATCHEZ TO MERIDIAN AND
SOUTH AND BE FOCUSED FROM ABOUT 3AM TO NOON SUNDAY. AN INCH OR TWO OF
RAIN CAN BE EXPECTED IN SOME AREAS BUT FLOODING IS NOT EXPECTED DUE
TO THE RAPID MOVEMENT OF THE SYSTEM.
THE STORMS WILL RACE EAST OF THE FORECAST AREA BY AROUND NOON SUNDAY.
THERE WILL BE A LAG BETWEEN THE STORMS AND THE COLD FRONT WHICH WILL
NOT PUSH THROUGH THE AREA UNTIL SUNDAY NIGHT. WITH STRONG MIXING DUE
TO THE MID LEVEL DRYING AND TEMPERATURES APPROACHING 80 DEGREES...
EXPECT TO HAVE WIND GUSTS TO 35 MPH SUNDAY AFTERNOON ACROSS MUCH OF
THE FORECAST AREA SOUTH OF HIGHWAY 82. WILL HAVE DRY CONDITIONS AFTER
NOON SUNDAY FOR MUCH OF THE FORECAST AREA...BUT WILL NEED TO CARRY
SMALL POPS DUE TO THE PROXIMITY OF THE UPPER LOW IN THE MS DELTA.
CONDITIONS WILL BECOME MORE TRANQUIL ON SUNDAY NIGHT AND MONDAY. THE
COLD FRONT WILL PUSH THROUGH BUT HIGHS WILL STILL REACH INTO THE 60S
ON MONDAY. /SW/
LONG TERM...MONDAY NIGHT THROUGH NEXT FRIDAY...A DRY AND COOLER
PATTERN IS IN STORE FOR THE ARKLAMISS THANKSGIVING WEEK AS A WESTERN
RIDGE AND EASTERN TROUGH PATTERN SETS UP AND BRINGS DRY NORTHWEST
FLOW ALOFT. EXPECT SURFACE TEMPERATURES TO BE 5-10 DEG F BELOW NORMAL
FOR THE MOST PART. CIPS SHOWS SUBSTANTIAL NEGATIVE TEMPERATURE
ANOMALIES...BUT THIS POLAR AIRMASS WILL NOT BE NEARLY AS COLD AS THE
RECENT ARCTIC AIR OUTBREAK. IT APPEARS THE NEXT SIGNIFICANT CHANCE
FOR RAINFALL MAY NOT MATERIALIZE UNTIL THE FIRST WEEK OF DECEMBER. /EC/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 47 71 58 79 / 5 5 96 99
MERIDIAN 42 72 56 77 / 5 5 86 100
VICKSBURG 48 75 58 80 / 16 5 100 87
HATTIESBURG 45 71 59 81 / 6 6 89 100
NATCHEZ 52 75 61 78 / 18 7 100 70
GREENVILLE 50 71 56 74 / 20 20 96 100
GREENWOOD 51 74 56 77 / 7 6 88 100
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
DC/26/SW/EC/
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
921 PM CST Fri Nov 21 2014
.UPDATE...
Issued at 912 PM CST FRI NOV 21 2014
Trimmed back overnight PoPs as deeper moisture as noted in IR
satellite imagery and radar returns is peeling off to the northeast.
00z NAM and RUC h7 condensation pressure deficit progs support this
as does the miniscuel reflectivity returns on the HRRR. Bufr
soundings are more supportive of drizzle forming overnight. Will
stratify PoPs with best chances for rain over the southeast 1/3 of
the CWA. Deeper moisture doesn`t arrive from teh southwest until
later Saturday afternoon so until then think low chance PoPs the best
one can do.
&&
.DISCUSSION...
Issued at 309 PM CST FRI NOV 21 2014
Main concern in the short term will be fog, stratus, and light
showers as a broad area of warm air advection continues across the
region. Without a strong focus for lift, any precipitation tonight
into Saturday should be fairly light throughout the region. Dense
fog looks likely mainly across eastern Kansas and northwest MO where
moisture will remain fairly shallow; farther to the southeast, low
stratus and continued isolated showers seem more likely. May need a
dense fog advisory in far western and northwestern portions of the
CWA tonight, but will wait to see how efficiently fog develops later
this evening. Another round of dense fog looks possible on Saturday
night across far northern MO and especially further to the north in
IA, with continued stratus to the south.
Rain will become more widespread for Sunday as a shortwave trough
lifts out of the southern Plains and into eastern MO, and a surface
low tightens up over central portions of the state. Rain is most
likely and potential precipitation totals are highest across far
eastern portions of the CWA, but at least some rainfall is likely as
far west as the KC metro during the daylight hours. Timing for the
exit of this system is still a little uncertain, but rain should be
tapering off by late Sunday evening into the early morning hours
Monday. A second system is still also expected to sweep in from the
northern Plains on Sunday, bringing colder air into northern MO by
late Sunday and into the remainder of the state on Monday. Rain may
briefly mix with or change over to snow in northern MO late Sunday
night or early Monday as the first system departs and cold air
surges in, but warm/wet ground and depleted moisture will prevent
any snow accumulation.
Colder temperatures are expected Monday and Tuesday as the second
system continues to dive southeast and allows Canadian air to filter
into the central CONUS; then some brief warming is possible
Wednesday as that system departs. The latest 2 runs of both the EC
and GFS have finally come into much better alignment for Thursday
and Friday, indicating a rather cold but dry Thanksgiving, but a
quick warm up for Friday beyond the end of the period. Have removed
all PoPs beyond the weekend system, leaving the long-range forecast
period dry.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday Evening)
Issued at 550 PM CST FRI NOV 21 2014
Cigs and fog will be the primary concerns. An area of dense fog and
LIFR cigs over central KS lines up well with the latest HRRR and SREF
short range models and they spread LIFR cigs/dense fog into northwest
MO later this evening and eventually across all of northern MO.
Appears the deeper moisture advecting into west central and central
MO will result in mainly a lowering of cigs to IFR/LIFR overnight and
ward off the dense fog. Depth of moisture will maintain cloud cover
with improvement only to MVFR in the afternoon.
Precipitation will be light and limited to mostly patchy and
intermittent drizzle overnight. Showers will be more likely east of
the terminals from southwest into central MO, decreasing in coverage
to isolated towards the MO/KS state line.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
UPDATE...MJ
DISCUSSION...Laflin
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
556 PM CST Fri Nov 21 2014
.DISCUSSION...
Issued at 309 PM CST FRI NOV 21 2014
Main concern in the short term will be fog, stratus, and light
showers as a broad area of warm air advection continues across the
region. Without a strong focus for lift, any precipitation tonight
into Saturday should be fairly light throughout the region. Dense
fog looks likely mainly across eastern Kansas and northwest MO where
moisture will remain fairly shallow; farther to the southeast, low
stratus and continued isolated showers seem more likely. May need a
dense fog advisory in far western and northwestern portions of the
CWA tonight, but will wait to see how efficiently fog develops later
this evening. Another round of dense fog looks possible on Saturday
night across far northern MO and especially further to the north in
IA, with continued stratus to the south.
Rain will become more widespread for Sunday as a shortwave trough
lifts out of the southern Plains and into eastern MO, and a surface
low tightens up over central portions of the state. Rain is most
likely and potential precipitation totals are highest across far
eastern portions of the CWA, but at least some rainfall is likely as
far west as the KC metro during the daylight hours. Timing for the
exit of this system is still a little uncertain, but rain should be
tapering off by late Sunday evening into the early morning hours
Monday. A second system is still also expected to sweep in from the
northern Plains on Sunday, bringing colder air into northern MO by
late Sunday and into the remainder of the state on Monday. Rain may
briefly mix with or change over to snow in northern MO late Sunday
night or early Monday as the first system departs and cold air
surges in, but warm/wet ground and depleted moisture will prevent
any snow accumulation.
Colder temperatures are expected Monday and Tuesday as the second
system continues to dive southeast and allows Canadian air to filter
into the central CONUS; then some brief warming is possible
Wednesday as that system departs. The latest 2 runs of both the EC
and GFS have finally come into much better alignment for Thursday
and Friday, indicating a rather cold but dry Thanksgiving, but a
quick warm up for Friday beyond the end of the period. Have removed
all PoPs beyond the weekend system, leaving the long-range forecast
period dry.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday Evening)
Issued at 550 PM CST FRI NOV 21 2014
Cigs and fog will be the primary concerns. An area of dense fog and
LIFR cigs over central KS lines up well with the latest HRRR and SREF
short range models and they spread LIFR cigs/dense fog into northwest
MO later this evening and eventually across all of northern MO.
Appears the deeper moisture advecting into west central and central
MO will result in mainly a lowering of cigs to IFR/LIFR overnight and
ward off the dense fog. Depth of moisture will maintain cloud cover
with improvement only to MVFR in the afternoon.
Precipitation will be light and limited to mostly patchy and
intermittent drizzle overnight. Showers will be more likely east of
the terminals from southwest into central MO, decreasing in coverage
to isolated towards the MO/KS state line.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...Laflin
AVIATION...MJ
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
550 PM CST Fri Nov 21 2014
.SHORT TERM: (Through Late Tonight)
Issued at 349 PM CST Fri Nov 21 2014
Will continue the chance of light rain as low level moisture
convergence and large scale ascent increases ahead of shortwave
trough currently moving towards us across the central Plains. There
are two small areas of rain that have developed ahead of this
system...one over west central Missouri which will move into central
and northeast Missouri later this afternoon and a second over
northern Arkansas which will move into southeast Missouri. Rain
chances will increase areawide this evening as aforementioned trough
moves across Missouri and Illinois. Chances will continue through
the night as a 50kt low level jet sets up over the region which will
provide more low level moisture convergence. At this time it still
appears that precipitation from this event will be mostly liquid as
dewpoints are steadily rising as rain moves into the area. Both the
HRRR and RUC are showing that the surface wet-bulb temperatures will
be at or above freezing during the onset of precipitation through
early this evening with temperatures continuing to rise through the
late evening hours.
Britt
.LONG TERM: (Saturday through Next Friday)
Issued at 349 PM CST Fri Nov 21 2014
At least scattered light showers can be expected Saturday and
Saturday night due to low-mid level warm air advection and as a
southwesterly low level jet continues to bring low level moisture
into the area. The best chance of rain along with the highest
rainfall amounts should occur on Sunday as a southern stream
negatively tilted shortwave moves through the southern Plains and
into the TN Valley region, while an upper level low moves
southeastward into the northern Plains. There will be upper level
divergence over our area between an upper level jet streak across
the southern Plains and another upper level jet streak across the
Great Lakes region. A surface low will develop and deepen as it
moves northeastward through the St Louis area around 00z Monday.
There should be at least isolated thunderstorms across portion sof
central and southeast MO and southwest IL. Temperatures will be
much warmer this weekend and above normal for a change. Much of the
precipitation should shift east of our forecast area Sunday night as
colder and drier air filters southeastward into the region behind
the surface low and trailing cold front. There may be some
lingering precipitation Sunday night into Monday morning as
shortwaves move through the area south of the upper level low which
will progress slowly eastward into the Great Lakes region. The rain
may change over to some light snow across northeast MO and west
central IL late Sunday night and Monday as colder air continues to
advect into the region. Temperatures will return to below normal
values beginning Monday with both the GFS and ECMWF models dropping
the -8 degree C 850 mb isotherm down to STL by 18z Monday. Below
normal temperatures are expected from Monday through Thanksgiving
with little if any precipitation as a deep upper level trough moves
slowly eastward through the central US. The ECMWF model does drop a
northwest flow, clipper type shortwave and associated weak surface
low southeastward through our area which could bring the potential
for a brief period of snow on Wednesday, but the GFS is much weaker
with this feature and only has very light QPF. A strong surface
ridge will build southeastward into MO for Wednesday night and
Thanksgiving Day with unseasonably cold temperatures expected.
GKS
&&
.AVIATION: (For the 00z TAFs through 00z Saturday Evening)
Issued at 522 PM CST Fri Nov 21 2014
MVFR cigs are expected to prevail overnight, however there may be
occasional brief periods of low-end VFR ceilings. Widely scattered
rain showers are possible through the period, especially at KCOU and
KUIN. A 50kt southwesterly LLJ will likely produce LLWS conditions
at all terminals between 05-14z.
Specifics for KSTL: MVFR cigs are expected to prevail overnight,
however there may be occasional brief periods of low-end VFR
ceilings. Widely scattered rain showers are possible through the
period. The highest rain chances at KSTL are expected beyond the
end of the 30-hr TAF period. A 50kt southwesterly low level jet
will likely produce LLWS conditions between 05-14z.
Kanofsky
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
956 PM CST FRI NOV 21 2014
.UPDATE...
ISSUED AT 956 PM CST FRI NOV 21 2014
ADJUSTED CLOUD COVER A BIT FOR TIMING OF STRATUS COMING DOWN OUT
OF CANADA. MODEL SOUNDINGS FOR OUR NORTHEASTERN COUNTIES SHOW SOME
FAVORABLY FOR FREEZING DRIZZLE WITH A LOW LEVEL SATURATED LAYER
AND DRY AIR ALOFT. ON THE OTHER HAND...NOT MUCH RISING MOTION IN
SAID SATURATED LAYER AND LOOKING AT THE CLOUD LEVELS OBSERVED
UPSTREAM IN CANADA MOST ARE ABOVE 1000 FT. WOULD LIKE TO HAVE SOME
CLOSER DEW POINT DEPRESSIONS AND LOWER CEILINGS FOR DRIZZLE
FORMATION SO WILL KEEP MENTION OUT FOR NOW. WILL KEEP THE PATCHY
FOG MENTION IN THE NORTHWEST HOWEVER AS WINDS BEGIN TO GO LIGHT
AHEAD OF THE CLOUDS COMING IN AND THERE COULD BE SOME RADIATING
OUT A JUST SOME PATCHES OF FOG IN AREAS WHERE THERE WAS SNOW MELT
TODAY. ADJUSTED TEMPS UP A BIT AS MANY LOCATIONS HAVE BEEN STAYING
IN THE UPPER 20S TO 30S. THINK THERE WILL BE SOME FALLING BUT WITH
A FAIRLY WARM AIR MASS AND CLOUDS COMING IN LOWS WILL STAY IN THE
20S OVERNIGHT.
UPDATE ISSUED AT 644 PM CST FRI NOV 21 2014
WINDS WILL CONTINUE TO DIMINISH MAINLY IN THE NORTHWESTERN
COUNTIES WHERE THE TROUGH AXIS WILL ARRIVE LATER TONIGHT. WITH
LIGHT WINDS AND SOME DECENT RADIATING OUT...THINK SOME PATCHY FOG
IN SOME AREAS IS POSSIBLE. RAP HAS SOME LOW VIS IN THE NORTHWEST
SO KEPT A MENTION FOR THE DEVILS LAKE BASIN INTO THE NORTHERN RED
RIVER VALLEY.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 323 PM CST FRI NOV 21 2014
SYSTEM TRACKING ACROSS SOUTHERN CANADA WILL CONTINUE EASTWARD
OVERNIGHT...RESULTING IN A WEAK COLD FRONT TO NEAR THE
INTERNATIONAL BORDER (MAIN RESULT WILL BE INCREASED CLOUD COVER).
THIS FEATURE WILL QUICKLY BE WASHED OUT AS THE NEXT SYSTEM
APPROACHES AND SOUTHERLY RETURN FLOW AGAIN DEVELOPS ON SATURDAY.
TEMPERATURES WILL BE THE MAIN CHALLENGE...WITH SATURDAY MAX TEMPS
SIMILAR OR EVEN SLIGHTLY WARMER (ESPECIALLY ACROSS THE SOUTHERN
FA) THAN TODAYS...BUT NOT SURE HOW MUCH WARMER.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 323 PM CST FRI NOV 21 2014
SATURDAY NIGHT-MONDAY...CONFIDENCE REMAINS LOW DURING THIS PERIOD
REGARDING HOW THE UPPER LOW WILL EVOLVE. MODELS ALL AGREE THAT THE
SOUTHERN SYSTEM WILL BE WELL EAST OF THE REGION...BUT COULD STILL
ACT TO SLOW DOWN THE NORTHERN WAVE THAT WILL AFFECT THIS REGION.
THE GFS IS SLIGHTLY QUICKER SATURDAY NIGHT AND INDICATES A BAND OF
PRECIP ASSOCIATED WITH 700MB CONVERGENCE/DEFORMATION. IF PRECIP
DOES OCCUR...IT COULD BE FREEZING RAIN/SLEET GIVEN THE WARM
TEMPERATURES ALOFT. DID INCLUDE A SCHC FOR MIXED PRECIP...BUT WITH
OTHER MODELS DRY (SLOWER) CANNOT GO WITH HIGHER POPS. THE UPPER
LOW THEN MOVES ACROSS THE REGION LATER SUNDAY INTO MONDAY. AS
THIS OCCURS...ANTICIPATE STRONG N/NW WINDS ALONG WITH SNOW
SHOWERS. AS OF NOW...WINDS ALONG AND WEST OF THE VALLEY SHOULD BE
30-40 MPH WITH HIGHER GUSTS (GIVEN EXPECTED COLD AIR
ADVECTION...SFC PRESSURE GRADIENT...AND WIND SPEEDS ALOFT). THESE
WINDS COMBINED WITH SNOW SHOWERS WOULD RESULT IN BRIEF PERIODS OF
SIGNIFICANTLY REDUCED VISIBILITY. ANY SNOW-PACK CURRENTLY ON THE
GROUND WILL NOT BE BLOW-ABLE WITH TEMPERATURES ABOVE FREEZING
DURING THE DAY TODAY...SATURDAY...AND POSSIBLY SUNDAY. SO...HOW
MUCH SNOW ACTUALLY FALLS WILL DETERMINE HOW WIDESPREAD THE BLOWING
SNOW IS DURING THIS PERIOD. STRONGEST FORCING WILL BE NORTH OF THE
INTERNATIONAL BORDER...AND GIVEN THE EXPECTED FORCING OVER THIS
REGION THINKING 1-2 INCHES AT MOST SOUTH OF THE INTERNATIONAL
BORDER (ALTHOUGH GFS INDICATES A STRONGER SYSTEM AND HIGHER QPF).
WILL CONTINUE TO MONITOR...BUT THE CURRENT MENTION IN THE HWO AND
WEATHER STORY SEEMS LIKE THE APPROPRIATE PRODUCTS AT THIS MOMENT
IN TIME.
MONDAY NIGHT-FRIDAY...500 MB TROUGH OVER THE GREAT LAKES REGION
MONDAY NIGHT INTO THURSDAY WITH FCST AREA ON THE COLD SIDE. CLOUDS
AND A CHANCE FOR SOME LIGHT SNOW WILL OCCUR TUESDAY INTO TUESDAY
NIGHT AHEAD OF A WEAK UPPER DISTURBANCE WHICH WILL MOVE THROUGH.
COLDEST AIRMASS AND HIGH PRESSURE SYSTEM TO ARRIVE WEDNESDAY-
THURSDAY. MODERATION OCCURS FRIDAY BUT LONG RANGE MODELS KEEP AREA
NEAR THE TIGHT BAROCLINIC ZONE BETWEEN COLD NORTH AND WARMER
SOUTHWEST. 12Z GFS/ECMWF SEEM IN GOOD AGREEMENT AND BLENDS WELL
WITH BLENDED MODEL DATA PROCEDURE. GOOD NEWS IS NO SIGNIFICANT
STORM SYSTEM FOR THE THANKSGIVING DAY TRAVEL PERIOD LOCALLY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 644 PM CST FRI NOV 21 2014
VFR CONDITIONS CONTINUE AT ALL TAF SITES...BUT WITH A FRONTAL
BOUNDARY SAGGING INTO THE NORTHERN FORECAST AREA THINK THERE COULD
BE SOME REDUCTIONS IN CIGS TOWARDS MORNING. SOME PATCHY FOG IS
ALSO POSSIBLE IN SOME AREAS BUT THINK THE CHANCES ARE NOT HIGH
ENOUGH TO PUT IN THE TAFS AT THIS TIME. WINDS WILL BECOME LIGHT
AND VARIABLE EARLY SATURDAY MORNING AND ALL BUT THE FAR NORTHERN
TAF SITES SHOULD SEE AT LEAST A SHORT PERIOD OF MVFR CIGS. THINK
THERE SHOULD BE SOME RECOVERY BACK TO VFR AS THE FRONT WASHES OUT
AND WINDS PICK BACK UP OUT OF THE SOUTHEAST DURING THE DAY ON
SATURDAY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...TG
LONG TERM...TG/RIDDLE
AVIATION...JR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
644 PM CST FRI NOV 21 2014
.UPDATE...
ISSUED AT 644 PM CST FRI NOV 21 2014
WINDS WILL CONTINUE TO DIMINISH MAINLY IN THE NORTHWESTERN
COUNTIES WHERE THE TROUGH AXIS WILL ARRIVE LATER TONIGHT. WITH
LIGHT WINDS AND SOME DECENT RADIATING OUT...THINK SOME PATCHY FOG
IN SOME AREAS IS POSSIBLE. RAP HAS SOME LOW VIS IN THE NORTHWEST
SO KEPT A MENTION FOR THE DEVILS LAKE BASIN INTO THE NORTHERN RED
RIVER VALLEY.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 323 PM CST FRI NOV 21 2014
SYSTEM TRACKING ACROSS SOUTHERN CANADA WILL CONTINUE EASTWARD
OVERNIGHT...RESULTING IN A WEAK COLD FRONT TO NEAR THE
INTERNATIONAL BORDER (MAIN RESULT WILL BE INCREASED CLOUD COVER).
THIS FEATURE WILL QUICKLY BE WASHED OUT AS THE NEXT SYSTEM
APPROACHES AND SOUTHERLY RETURN FLOW AGAIN DEVELOPS ON SATURDAY.
TEMPERATURES WILL BE THE MAIN CHALLENGE...WITH SATURDAY MAX TEMPS
SIMILAR OR EVEN SLIGHTLY WARMER (ESPECIALLY ACROSS THE SOUTHERN
FA) THAN TODAYS...BUT NOT SURE HOW MUCH WARMER.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 323 PM CST FRI NOV 21 2014
SATURDAY NIGHT-MONDAY...CONFIDENCE REMAINS LOW DURING THIS PERIOD
REGARDING HOW THE UPPER LOW WILL EVOLVE. MODELS ALL AGREE THAT THE
SOUTHERN SYSTEM WILL BE WELL EAST OF THE REGION...BUT COULD STILL
ACT TO SLOW DOWN THE NORTHERN WAVE THAT WILL AFFECT THIS REGION.
THE GFS IS SLIGHTLY QUICKER SATURDAY NIGHT AND INDICATES A BAND OF
PRECIP ASSOCIATED WITH 700MB CONVERGENCE/DEFORMATION. IF PRECIP
DOES OCCUR...IT COULD BE FREEZING RAIN/SLEET GIVEN THE WARM
TEMPERATURES ALOFT. DID INCLUDE A SCHC FOR MIXED PRECIP...BUT WITH
OTHER MODELS DRY (SLOWER) CANNOT GO WITH HIGHER POPS. THE UPPER
LOW THEN MOVES ACROSS THE REGION LATER SUNDAY INTO MONDAY. AS
THIS OCCURS...ANTICIPATE STRONG N/NW WINDS ALONG WITH SNOW
SHOWERS. AS OF NOW...WINDS ALONG AND WEST OF THE VALLEY SHOULD BE
30-40 MPH WITH HIGHER GUSTS (GIVEN EXPECTED COLD AIR
ADVECTION...SFC PRESSURE GRADIENT...AND WIND SPEEDS ALOFT). THESE
WINDS COMBINED WITH SNOW SHOWERS WOULD RESULT IN BRIEF PERIODS OF
SIGNIFICANTLY REDUCED VISIBILITY. ANY SNOW-PACK CURRENTLY ON THE
GROUND WILL NOT BE BLOW-ABLE WITH TEMPERATURES ABOVE FREEZING
DURING THE DAY TODAY...SATURDAY...AND POSSIBLY SUNDAY. SO...HOW
MUCH SNOW ACTUALLY FALLS WILL DETERMINE HOW WIDESPREAD THE BLOWING
SNOW IS DURING THIS PERIOD. STRONGEST FORCING WILL BE NORTH OF THE
INTERNATIONAL BORDER...AND GIVEN THE EXPECTED FORCING OVER THIS
REGION THINKING 1-2 INCHES AT MOST SOUTH OF THE INTERNATIONAL
BORDER (ALTHOUGH GFS INDICATES A STRONGER SYSTEM AND HIGHER QPF).
WILL CONTINUE TO MONITOR...BUT THE CURRENT MENTION IN THE HWO AND
WEATHER STORY SEEMS LIKE THE APPROPRIATE PRODUCTS AT THIS MOMENT
IN TIME.
MONDAY NIGHT-FRIDAY...500 MB TROUGH OVER THE GREAT LAKES REGION
MONDAY NIGHT INTO THURSDAY WITH FCST AREA ON THE COLD SIDE. CLOUDS
AND A CHANCE FOR SOME LIGHT SNOW WILL OCCUR TUESDAY INTO TUESDAY
NIGHT AHEAD OF A WEAK UPPER DISTURBANCE WHICH WILL MOVE THROUGH.
COLDEST AIRMASS AND HIGH PRESSURE SYSTEM TO ARRIVE WEDNESDAY-
THURSDAY. MODERATION OCCURS FRIDAY BUT LONG RANGE MODELS KEEP AREA
NEAR THE TIGHT BAROCLINIC ZONE BETWEEN COLD NORTH AND WARMER
SOUTHWEST. 12Z GFS/ECMWF SEEM IN GOOD AGREEMENT AND BLENDS WELL
WITH BLENDED MODEL DATA PROCEDURE. GOOD NEWS IS NO SIGNIFICANT
STORM SYSTEM FOR THE THANKSGIVING DAY TRAVEL PERIOD LOCALLY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 644 PM CST FRI NOV 21 2014
VFR CONDITIONS CONTINUE AT ALL TAF SITES...BUT WITH A FRONTAL
BOUNDARY SAGGING INTO THE NORTHERN FORECAST AREA THINK THERE COULD
BE SOME REDUCTIONS IN CIGS TOWARDS MORNING. SOME PATCHY FOG IS
ALSO POSSIBLE IN SOME AREAS BUT THINK THE CHANCES ARE NOT HIGH
ENOUGH TO PUT IN THE TAFS AT THIS TIME. WINDS WILL BECOME LIGHT
AND VARIABLE EARLY SATURDAY MORNING AND ALL BUT THE FAR NORTHERN
TAF SITES SHOULD SEE AT LEAST A SHORT PERIOD OF MVFR CIGS. THINK
THERE SHOULD BE SOME RECOVERY BACK TO VFR AS THE FRONT WASHES OUT
AND WINDS PICK BACK UP OUT OF THE SOUTHEAST DURING THE DAY ON
SATURDAY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...TG
LONG TERM...TG/RIDDLE
AVIATION...JR
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
319 PM EST THU NOV 20 2014
.SYNOPSIS...
LOW PRESSURE OVER SOUTHERN QUEBEC WILL MOVE EAST TONIGHT BUT LEAVE
A TROUGH OF LOW PRESSURE EXTENDING SOUTHWEST ACROSS THE CENTRAL
GREAT LAKES. HIGH PRESSURE WILL BUILD ACROSS THE OHIO VALLEY ON
FRIDAY. SUNDAY THE HIGH WILL MOVE OFF THE MID ATLANTIC COAST
ALLOWING DEEP LOW PRESSURE TO MOVE INTO THE GREAT LAKES REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
WILL CONTINUE WINTER WX HEADLINES AS THEY ARE. FORECAST STILL ON
TRACK WITH RADAR SHOWING INCREASING ACTIVITY ON THE LAKE IN
RESPONSE TO SHORT WAVE ENERGY MOVING TOWARD THE AREA FROM
MICHIGAN...WITH THE START OF THE BANDS NOW INVOF THE ISLANDS.
WINDS HAVE BACKED JUST A BIT THROUGH THE LATE MORNING AND EARLY
AFTERNOON AS PREVIOUSLY THOUGHT WOULD HAPPEN. BUFKIT FORECAST
SOUNDINGS HOWEVER CONTINUE TO SHOW WINDS VEERING THROUGH THE
EVENING WHICH WILL BRING SNOW ONSHORE. CONCERN FOR THE OVERNIGHT
IS THAT WHILE THE HRRR BRINGS THE BAND ONSHORE THE INTENSITY ALSO
DECREASES BEFORE NEW BANDS SET UP IN MORE OF A NORTHWEST FLOW.
LOCAL MODELS HOWEVER DEVELOP MORE LIFT/RADAR RETURN RESULTING IN
BETTER SNOW TOTALS. BELIEVE THAT WITH MODERATE TO EXTREME
INSTABILITY...LOW LEVEL LIFT AND FAVORABLE SNOW GROWTH
TEMPERATURES WITHIN THE MOIST AIR...SNOW IN THE NORTHWEST BANDS
OUTCOME WILL BETTER RESEMBLE LOCAL MODEL FORECAST. OUTSIDE OF LAKE
EFFECT NOT MUCH MORE THAT FLURRIES OR LIGHT SNOW SHOWERS EARLY.
THINKING THAT MUCH OF THE CLOUD COVER WHICH DEVELOPED WITH
AFTERNOON HEATING WILL DECREASE THROUGH THE EVENING AND
OVERNIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
FORECAST BEGINS WITH SNOW ONGOING ACROSS NWRN PA AND NERN OHIO
ALTHOUGH DRY AIR WILL BE MOVING IN FAST TO BELIEVE SNOW WILL BE
COMING TO AN END RATHER QUICKLY FROM THE WEST. END TIME OF THE
ADVISORY STILL LOOKS FINE AT 10AM. FLOW REMAINS OFF THE LAKE NWRN
PA BUT LOW LEVEL WINDS BACK AND WARM ADVECTION MOVES IN AT LEAST
TO THE GENERATION AREA OF THE BANDS SO SNOW SHOULD TAPER/END
EITHER LATE MORNING OR EARLY AFTERNOON. HIGH PRESSURE OVER THE
AREA FRIDAY WILL MOVE EAST FRIDAY NIGHT BRINGING WARM AIR FRIDAY
NIGHT THROUGH SATURDAY. MODELS BRING OVERRUNNING MOISTURE NORTH
ACROSS THE MISSISSIPPI VALLEY INTO WESTERN OHIO LATE FRIDAY NIGHT
AND SATURDAY. EXPECT FRIDAY NIGHT LOWS TO BE EARLY WITH TEMPS
RISING OVERNIGHT FROM THE WEST. MAIN CONCERN WILL BE PTYPE AS THE
PRECIP GETS INTO THE AREA EITHER LATE FRIDAY NIGHT OR SATURDAY
MORNING. FOR NOW IT LOOKS AS IF THERE IS A REASONABLE CHANCE OF
PRECIP IN THE WEST BEFORE DAWN. TEMPS ALSO APPEAR THAT THEY WILL
NOT MOVE ABOVE FREEZING UNTIL 8-10AM SO PUT A CHANCE OF RAIN AND
FREEZING RAIN IN THE FORECAST WEST. THE REST OF THE WEEKEND LOOKS
MILD TO SEASONAL TEMP WISE WITH HIGH CHANCE TO LIKELY POPS.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
A COLD FRONT CROSSING THE AREA AND STRONG UPPER DYNAMICS WILL
COMBINE FOR A GOOD CHANCE FOR SHRA ON MON SO WILL CARRY LIKELY POPS.
SOME DRYING WILL FOLLOW THE FRONT THAT SHOULD PRODUCE A LULL IN THE
PRECIP AS TEMPS TURN COLDER AND ANY PRECIP THAT DOES OCCUR CHANGES
TO SNOW MON NIGHT INTO TUE. THE MODELS SHOW WRAP MOISTURE WORKING SE
BACK INTO THE AREA TUE WITH AN UPPER S/W. SHOULD SEE SHSN IN THE
SNOWBELT WITH A CHANCE FOR LIGHTER SHSN OR FLURRIES ELSEWHERE.
THE MODELS START TO DIFFER SOME WED INTO THU BUT IN GENERAL THERE
SHOULD BE A ANOTHER S/W DIGGING INTO THE MAIN UPPER TROUGH THAT
INDUCES A LOW TO MOVE OUT OF THE PLAINS INTO THE REGION BY THU OR
THU NIGHT. WILL KEEP AT LEAST A SMALL CHANCE OF POP IN THE FORECAST
THRU THU WITH EMPHASIS ON THE SNOWBELT. TEMPS WILL BE BELOW NORMAL
AND KEPT COLD ENOUGH FOR JUST SNOW AS THE PRECIP TYPE.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
A WEAK TROUGH WILL DROP SE INTO THE AREA THIS EVENING. THIS SHOULD
CAUSE THE LAKE EFFECT SHSN AFFECTING ERI TO DROP SE WHICH MAY LEAD
TO SOME IMPROVEMENT LATER INTO THE NIGHT AT ERI BUT WILL CAUSE THE
SHSN TO START TO AFFECT CLE AND YNG AND POSSIBLY EVEN SOME LIGHT
SHSN OR FLURRIES ALL THE WAY SOUTH INTO CAK. AS USUAL WITH THE
SHSN...CONDITIONS CAN WAVER FROM VFR/MVFR TO LOW IFR IN SHORT
DISTANCES AND IN SHORT PERIODS OF TIME.
WINDS GUSTING 25 TO 30 KNOTS WILL DIMINISH EARLY TONIGHT FOR ALL BUT
ERI WHERE GUSTS OF 20 TO 25 KNOTS MAY CONTINUE INTO FRI MORNING. THE
HIGHER WIND GUST WILL LEAD TO SOME BLOWING AND DRIFTING OF THE SNOW.
CONDITIONS SHOULD START TO IMPROVE FROM WEST TO EAST MIDDAY FRI AS
DRIER AIR MOVES IN FROM THE WEST.
.OUTLOOK...NON VFR CONDITIONS IN LAKE EFFECT SNOW IN THE SNOWBELT
WILL END WEST TO EAST FRI AFTERNOON INTO EARLY FRI NIGHT. AREAS OF
NON VFR SHOULD RETURN SAT NIGHT AND CONTINUE MOST OF THE TIME SUN
THRU TUE.
&&
.MARINE...
WINDS WILL START TO DIMINISH TONIGHT AND DIMINISH A LITTLE MORE ON
FRI BEFORE BACKING TO SW FRO FRI NIGHT. SCA CONDITIONS AND LOW WATER
PROBLEMS SHOULD END ON THE WEST END OF THE LAKE LATE TONIGHT INTO
FRI MORNING AND THE SCA MAY FINALLY BE ALLOWED TO END FRI EVENING ON
THE EAST PART OF THE LAKE. THE WINDS MAY KEEP ENOUGH OF A SOUTHERLY
DIRECTION TO KEEP 4 FOOT WAVES WELL OFFSHORE THRU SUN BUT WINDS MAY
GET INTO A 15 TO 25 KNOT RANGE ANYWAY TO REQUIRE SCA ADVISORIES.
IN ANY CASE...A FAIRLY STRONG LOW MOVES NE ACROSS THE UPPER LAKES
SUN NIGHT AND MON PULLING A COLD FRONT EAST ACROSS LAKE ERIE MONDAY.
EXPECT WINDS OF AT LEAST 15 TO 25 KNOTS BY MON THAT TURN MORE TOWARD
THE WEST BEHIND THE FRONT FOR MON NIGHT AND TUE. THIS WILL ALLOW
WAVES GREATER THAN 4 FOOT TO GET BACK INTO THE NEARSHORE WATERS SO A
SCA LOOKS ALMOST DEFINITE FOR THEN.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST FRIDAY FOR OHZ012.
LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST FRIDAY FOR OHZ013.
LAKE EFFECT SNOW WARNING UNTIL 3 PM EST FRIDAY FOR OHZ014-089.
PA...LAKE EFFECT SNOW WARNING UNTIL 3 PM EST FRIDAY FOR PAZ001>003.
MARINE...LOW WATER ADVISORY UNTIL 4 AM EST FRIDAY FOR LEZ142>144-
162>164.
SMALL CRAFT ADVISORY UNTIL 10 PM EST FRIDAY FOR LEZ147>149.
SMALL CRAFT ADVISORY UNTIL 4 AM EST FRIDAY FOR LEZ142>144.
SMALL CRAFT ADVISORY UNTIL 10 AM EST FRIDAY FOR LEZ145-146.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK
SHORT TERM...TK
LONG TERM...ADAMS
AVIATION...ADAMS
MARINE...ADAMS
AREA FORECAST DISCUSSION
NWS TULSA OK
1123 AM CST THU NOV 20 2014
.DISCUSSION...
THE 18Z TAF DISCUSSION IS INCLUDED BELOW...
&&
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
LOW LEVEL MOISTURE RETURN IN ADVANCE OF AN APPROACHING WAVE WILL
RESULT IN THE DEVELOPMENT AND SPREAD OF MVFR CIGS ACROSS E OK AND
NW AR DURING THE OVERNIGHT AND INTO FRIDAY. DOWN SOUTH TOWARD
KMLC...MOISTURE PROFILES SUGGEST CIGS WILL DROP INTO THE IFR RANGE
BY THE END OF THE FORECAST PERIOD.
LACY
&&
.PREV DISCUSSION... /ISSUED 1016 AM CST THU NOV 20 2014/
DISCUSSION...
THE UPPER FLOW PATTERN ACROSS THE CONUS HAS DEAMPLIFIED...AS THE
DEEP EASTERN CONUS TROUGH LIFTS OUT AND THE WESTERN RIDGE GETS
BROKEN DOWN BY SOME ENERGY ON THE NOSE OF THE EXTENDED CROSS-
PACIFIC JET. AT THE SURFACE...OUR AREA WILL REMAIN SANDWICHED
BETWEEN HIGH PRESSURE TO OUR NORTHEAST AND DEVELOPING LOW PRESSURE
OVER THE SOUTHERN HIGH PLAINS IN ADVANCE OF SOME ENERGY ON THE
NOSE OF THE JET. THE LOW LEVEL THERMAL RIDGE EXTENDS FROM WEST TX
UP INTO OUR AREA...SIMILAR TO YESTERDAY. THE MAIN CHANGE HAS BEEN
AT THE SURFACE...WHERE WINDS ARE MORE EASTERLY OR NORTHEASTERLY.
THIS INFLUENCE MAY BE THE ONLY THING THAT KEEPS UP FROM GETTING
QUITE AS WARM AS WE WERE YESTERDAY. REGARDLESS...WITH SOME MIXING
THE RELATIVELY WARM LOW LEVELS WILL PUSH HIGHS WELL INTO THE 50S
TO LOW 60S IN THE SOUTH. I MADE A SLIGHT TWEAK TO TODAYS HIGHS
USING SOME OF THE LATEST HRRR DATA.
LACY
PREV DISCUSSION... /ISSUED 521 AM CST THU NOV 20 2014/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
VFR CONDITIONS WILL CONTINUE THROUGH 00Z...WITH MOISTURE BEGINNING
TO INCREASE DURING THE EVENING AHEAD OF AN APPROACHING UPPER LEVEL
DISTURBANCE. THIS WILL ULTIMATELY RESULT IN WIDESPREAD MVFR
CEILINGS ACROSS SE OK/WC AR AFTER 03Z SPREADING NORTH AFTER 06Z.
SCATTERED SHOWERS AND TRANSITION TOWARD IFR CONDITIONS POSSIBLE
SOUTH TOWARD THE END OF THE FORECAST PERIOD.
PREV DISCUSSION... /ISSUED 316 AM CST THU NOV 20 2014/
DISCUSSION...
A WEAK SURFACE BOUNDARY WAS ANALYZED ACROSS NRN TX EARLY THIS
MORNING...WITH LIGHT ELY/NELY SFC FLOW AND A DRY AIRMASS IN PLACE
ACROSS THE FORECAST AREA. HIGHS TODAY WILL LIKELY BE JUST A BIT
COOLER THAN YESTERDAY...ALTHOUGH SE OK SHOULD SEE SIMILAR READINGS
AS THE AFOREMENTIONED BOUNDARY LIFTS N THIS AFTERNOON. RAPIDLY
IMPROVING LOW-LEVEL MOISTURE WILL RESULT IN SOME AREAS OF LIGHT
RAIN/SHOWERS LATER THURSDAY NIGHT INTO FRIDAY MORNING...ESPECIALLY
SOUTH OF I40.
A STRONGER UPPER SYSTEM WILL LIFT FROM THE DESERT SW FRIDAY AND INTO
TX BY SATURDAY...WITH SHOWER/THUNDERSTORM CHANCES INCREASING FOR OUR
REGION SATURDAY THROUGH SATURDAY NIGHT. FORECAST PW VALUES AT OR
ABOVE AN INCH (QUITE HIGH FOR THIS TIME OF THE YEAR) WILL SUPPORT
SOME LOCALLY HEAVY RAIN...ESPECIALLY ACROSS SE OK/ECNTRL OK/WRN AR
IN ZONE OF BEST UPPER DIFFLUENT FLOW. THE HEAVY RAIN AXIS WILL SHIFT
E OF THE REGION BY SUNDAY...ALTHOUGH WE MAY SEE SOME LINGERING
WRAPAROUND LIGHT PRECIPITATION SUNDAY INTO SUNDAY NIGHT. FORECAST
GOING INTO NEXT WEEK IS LOOKING DRIER AND COOLER...WITH TEMPS
FALLING BACK TO NEAR OR SLIGHTLY BELOW SEASONAL AVERAGES.
ONCE AGAIN...THE ECMWF REMAINS CONSISTENT BRINGING A SHOT OF ARCTIC
AIR TO THE SRN PLAINS BY THANKSGIVING DAY. WITH COLD AIR IN
PLACE...THE UPPER SYSTEM SHOWN BY THE ECMWF COULD RESULT IN WINTER
PRECIPITATION ACROSS ERN OK/NW AR FRIDAY NIGHT/SATURDAY. THIS IS
STILL OVER A WEEK AWAY AND JUST ONE MODEL SOLUTION...SO STAY TUNED.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 57 42 57 52 / 0 30 40 60
FSM 58 43 57 48 / 0 30 50 60
MLC 60 50 63 55 / 0 30 40 70
BVO 54 36 56 48 / 0 20 40 50
FYV 54 38 54 48 / 0 30 50 50
BYV 54 34 52 46 / 0 20 50 50
MKO 57 42 58 50 / 0 30 40 60
MIO 53 35 54 49 / 0 20 50 50
F10 59 44 61 53 / 0 30 40 60
HHW 61 51 63 54 / 10 40 50 80
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...30
AREA FORECAST DISCUSSION
NWS TULSA OK
1016 AM CST THU NOV 20 2014
.DISCUSSION...
THE UPPER FLOW PATTERN ACROSS THE CONUS HAS DEAMPLIFIED...AS THE
DEEP EASTERN CONUS TROUGH LIFTS OUT AND THE WESTERN RIDGE GETS
BROKEN DOWN BY SOME ENERGY ON THE NOSE OF THE EXTENDED CROSS-
PACIFIC JET. AT THE SURFACE...OUR AREA WILL REMAIN SANDWICHED
BETWEEN HIGH PRESSURE TO OUR NORTHEAST AND DEVELOPING LOW PRESSURE
OVER THE SOUTHERN HIGH PLAINS IN ADVANCE OF SOME ENERGY ON THE
NOSE OF THE JET. THE LOW LEVEL THERMAL RIDGE EXTENDS FROM WEST TX
UP INTO OUR AREA...SIMILAR TO YESTERDAY. THE MAIN CHANGE HAS BEEN
AT THE SURFACE...WHERE WINDS ARE MORE EASTERLY OR NORTHEASTERLY.
THIS INFLUENCE MAY BE THE ONLY THING THAT KEEPS UP FROM GETTING
QUITE AS WARM AS WE WERE YESTERDAY. REGARDLESS...WITH SOME MIXING
THE RELATIVELY WARM LOW LEVELS WILL PUSH HIGHS WELL INTO THE 50S
TO LOW 60S IN THE SOUTH. I MADE A SLIGHT TWEAK TO TODAYS HIGHS
USING SOME OF THE LATEST HRRR DATA.
LACY
&&
.PREV DISCUSSION... /ISSUED 521 AM CST THU NOV 20 2014/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
VFR CONDITIONS WILL CONTINUE THROUGH 00Z...WITH MOISTURE BEGINNING
TO INCREASE DURING THE EVENING AHEAD OF AN APPROACHING UPPER LEVEL
DISTURBANCE. THIS WILL ULTIMATELY RESULT IN WIDESPREAD MVFR
CEILINGS ACROSS SE OK/WC AR AFTER 03Z SPREADING NORTH AFTER 06Z.
SCATTERED SHOWERS AND TRANSITION TOWARD IFR CONDITIONS POSSIBLE
SOUTH TOWARD THE END OF THE FORECAST PERIOD.
PREV DISCUSSION... /ISSUED 316 AM CST THU NOV 20 2014/
DISCUSSION...
A WEAK SURFACE BOUNDARY WAS ANALYZED ACROSS NRN TX EARLY THIS
MORNING...WITH LIGHT ELY/NELY SFC FLOW AND A DRY AIRMASS IN PLACE
ACROSS THE FORECAST AREA. HIGHS TODAY WILL LIKELY BE JUST A BIT
COOLER THAN YESTERDAY...ALTHOUGH SE OK SHOULD SEE SIMILAR READINGS
AS THE AFOREMENTIONED BOUNDARY LIFTS N THIS AFTERNOON. RAPIDLY
IMPROVING LOW-LEVEL MOISTURE WILL RESULT IN SOME AREAS OF LIGHT
RAIN/SHOWERS LATER THURSDAY NIGHT INTO FRIDAY MORNING...ESPECIALLY
SOUTH OF I40.
A STRONGER UPPER SYSTEM WILL LIFT FROM THE DESERT SW FRIDAY AND INTO
TX BY SATURDAY...WITH SHOWER/THUNDERSTORM CHANCES INCREASING FOR OUR
REGION SATURDAY THROUGH SATURDAY NIGHT. FORECAST PW VALUES AT OR
ABOVE AN INCH (QUITE HIGH FOR THIS TIME OF THE YEAR) WILL SUPPORT
SOME LOCALLY HEAVY RAIN...ESPECIALLY ACROSS SE OK/ECNTRL OK/WRN AR
IN ZONE OF BEST UPPER DIFFLUENT FLOW. THE HEAVY RAIN AXIS WILL SHIFT
E OF THE REGION BY SUNDAY...ALTHOUGH WE MAY SEE SOME LINGERING
WRAPAROUND LIGHT PRECIPITATION SUNDAY INTO SUNDAY NIGHT. FORECAST
GOING INTO NEXT WEEK IS LOOKING DRIER AND COOLER...WITH TEMPS
FALLING BACK TO NEAR OR SLIGHTLY BELOW SEASONAL AVERAGES.
ONCE AGAIN...THE ECMWF REMAINS CONSISTENT BRINGING A SHOT OF ARCTIC
AIR TO THE SRN PLAINS BY THANKSGIVING DAY. WITH COLD AIR IN
PLACE...THE UPPER SYSTEM SHOWN BY THE ECMWF COULD RESULT IN WINTER
PRECIPITATION ACROSS ERN OK/NW AR FRIDAY NIGHT/SATURDAY. THIS IS
STILL OVER A WEEK AWAY AND JUST ONE MODEL SOLUTION...SO STAY TUNED.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 57 42 57 52 / 0 30 40 60
FSM 58 43 57 48 / 0 30 50 60
MLC 60 50 63 55 / 0 30 40 70
BVO 54 36 56 48 / 0 20 40 50
FYV 54 38 54 48 / 0 30 50 50
BYV 54 34 52 46 / 0 20 50 50
MKO 57 42 58 50 / 0 30 40 60
MIO 53 35 54 49 / 0 20 50 50
F10 59 44 61 53 / 0 30 40 60
HHW 61 51 63 54 / 10 40 50 80
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...30
AREA FORECAST DISCUSSION
NWS PENDLETON OR
1025 AM PST THU NOV 20 2014
.UPDATE...WITH THE STEADY PRECIPITATION ENDING AND TEMPERATURES
GRADUALLY RISING ABOVE FREEZING WE HAVE ALLOWED THE PREVIOUS WINTER
WEATHER ADVISORIES AND FREEZING RAIN ADVISORIES TO EXPIRE AS OF 10
AM. BASED ON LATEST RADAR TRENDS A BATCH OF VERY LIGHT PRECIPITATION
WAS ENTERING THE SOUTHWESTERN HALF OF THE CWA AND WILL CONTINUE TO
SLOWLY PUSH NORTHEAST TOWARD THE COLUMBIA GORGE...SIMCOE HIGHLANDS
AND YAKIMA VALLEY REGIONS INTO THIS AFTERNOON. THEREFORE DECIDED TO
UPDATE THE FORECAST TO ADD A SLIGHT CHANCE OF LIGHT RAIN OR FREEZING
THROUGH THIS AFTERNOON FOR THESE LOCATIONS. LEFT PATCHY FREEZING FOG
IN THE FORECAST FOR MUCH OF THE COLUMBIA BASIN INTO THIS AFTERNOON
AS WELL. THE LATEST HRRR MODEL IS DOING A DECENT JOB DEPICTING THIS
LIGHT PRECIPITATION AND ALSO SUGGEST TEMPERATURES SHOULD RISE ABOVE
FREEZING JUST ABOUT EVERYWHERE ACROSS THE CWA BY OR SHORTLY AFTER
MIDDAY. 77
&&
.PREV DISC... /ISSUED 943 AM PST THU NOV 20 2014/
UPDATE...THE LARGE AREA OF FZRA ACROSS THE BASIN AND FOOTHILLS OF
THE BLUE MOUNTAINS WAS DECREASING ACROSS THIS AREA BUT WILL CONTINUE
ALL ADVISORIES FOR ANOTHER TWO HOURS. ELSEWHERE A MIXTURE OF PCPN
HAD/WAS OCCURRING OVER THE BLUE MOUNTAINS AND EASTWARD. FURTHER WEST
DRIER CONDITIONS WERE PREVAILING ALTHOUGH ANOTHER WEAKER STORM
SYSTEM WILL EFFECT CENTRAL OREGON TODAY WITH SOME RAIN SHOWERS.
OTHERWISE THE REMAINDER OF THE FORECAST APPEARS ON TRACK FOR NOW
WITH THE AIR STAGNATION ADVISORY PERSISTING.
AVIATION...18Z TAFS...MVFR AND/OR IFR CONDITIONS WILL CONTINUE AT
KPDT...KALW...KDLS AND KPSC DUE TO FOG. AT KBDN AND KRDM CONDITIONS
WILL BE MOSTLY VFR WITH HIGHER CIGS AND BETTER VISIBILITY.
PRECIPITATION HAS MOSTLY ENDED...BUT THERE COULD STILL BE A FEW RAIN
SHOWERS NEAR KDLS...KRDM AND KBDN THROUGH THIS AFTERNOON. FOG CAN BE
EXPECTED TO LIFT OR THIN OUT THIS AFTERNOON...BUT WILL LIKELY RETURN
OVERNIGHT. WINDS WILL BE LIGHT AND LESS THAN 5 KTS AT ALL TAF SITES
THROUGH THE NEXT 24 HOURS. 82
PREV DISC... /ISSUED 300 AM PST THU NOV 20 2014/
SHORT TERM...TODAY THROUGH FRIDAY NIGHT. UPPER LEVEL SHORT WAVE
CURRENTLY MOVING ACROSS THE NORTHERN PORTION OF THE FORECAST AREA.
THIS IS PRODUCING A MIX OF RAIN AND FREEZING RAIN. THE SHORT WAVE
LOOKED FAIRLY WEAK ON SATELLITE FOR THE PAST 6 HOURS PRODUCING
LITTLE TO NO PRECIPITATION...THEN SUDDENLY INTENSIFIED AS IT MOVED
INTO NORTHEAST OREGON AND THE COLUMBIA BASIN OF WASHINGTON. EXPECT A
PERIOD OF MIXED PRECIPITATION FOR SEVERAL HOURS BEFORE EXITING OFF
TO THE NORTH TOWARD DAYBREAK. LIGHT ICE ACCUMULATIONS ARE LIKELY.
OTHERWISE SATELLITE SHOWING AN UPPER LOW MOVING TOWARD THE COAST.
THIS LOW WILL CROSS OREGON AND NORTHERN CALIFORNIA TODAY. THIS WILL
BRING ADDITIONAL CLOUDS INTO THE REGION...WITH SOME LIGHT RAIN
MOSTLY OVER OREGON AND THE WASHINGTON CASCADES. MIXING OF THE
ATMOSPHERE HAS IMPROVED THE FOG IN THE COLUMBIA BASIN FOR MANY
LOCATIONS. NOT ENOUGH TO BREAK THE INVERSION THOUGH AND WILL
CONTINUE WITH PATCHY FREEZING FOG THROUGH THE DAY. AS THE UPPER LOW
MOVES OFF TO THE EAST TONIGHT ANY LINGERING PRECIPITATION WILL END
ALTHOUGH SKIES WILL REMAIN MOSTLY CLOUDY. FOG WILL CONTINUE IN THE
COLUMBIA BASIN AND VALLEYS. A STRONGER AND WARMER SYSTEM WILL BE
APPROACHING THE PACIFIC NORTHWEST ON FRIDAY. CLOUDS WILL INCREASE
AND RAIN WILL OVERSPREAD THE REGION DURING THE AFTERNOON AND
EVENING. THIS SYSTEM MOVES THROUGH FRIDAY NIGHT. MODELS SHOWING
FAIRLY HIGH QPF AMOUNTS AND EXPECT ALL LOCATIONS TO HAVE A PERIOD OF
STEADY RAIN. THE CASCADES COULD SEE SOME HEAVY RAIN. TEMPERATURES
WILL BE WARMING UP OVER THE NEXT 2 DAYS. HIGHS ON FRIDAY WILL BE
UPPER 30S AND 40S. INCREASING WINDS FRIDAY AFTERNOON INTO THE
OVERNIGHT PERIOD. 94
LONG TERM...SATURDAY THROUGH THURSDAY...A STRONG SYSTEM WILL BE
OVER THE AREA SATURDAY AND WILL GIVE THE AREA A CHANCE OF RAIN IN
THE MORNING AND WILL TAPER OFF TO SHOWERS IN THE AFTERNOON. SNOW
LEVELS WILL BE 4500 TO 5500 FEET IN THE MORNING AND DROP TO 3500 TO
4000 FEET IN THE AFTERNOON. THE HEAVIER PRECIPITATION WILL BE MOSTLY
OVER BY THE TIME THE SNOW LEVELS DROP SO SNOW AMOUNTS IN THE
MOUNTAINS WILL BE AN INCH OR LESS. A MOIST UPSLOPE FLOW IN THE
MOUNTAINS WILL KEEP A CHANCE OF RAIN AND SNOW SHOWERS SATURDAY NIGHT
WHILE THE LOWER ELEVATIONS WILL HAVE A SLIGHT CHANCE OF RAIN
SHOWERS. ANOTHER SYSTEM WILL MOVE THROUGH THE AREA SUNDAY AND SUNDAY
NIGHT WITH ANOTHER ROUND OF A CHANCE OF RAIN WITH SNOW ABOVE 3500
FEET DURING THE DAY AND THEN TAPERING OFF OVERNIGHT. AFTER A BRIEF
BREAK ANOTHER SYSTEM ARRIVES MONDAY AFTERNOON AND NIGHT AND YET
ANOTHER SYSTEM ON TUESDAY. MODELS DIVERGE AT THIS POINT WITH THE GFS
BUILDING A RIDGE FOR MAINLY DRY WEATHER WEDNESDAY THROUGH THURSDAY
WHILE THE ECMWF DEVELOPS ANOTHER INTRUSION OF COLD AIR FROM CANADA
FED BY MOISTURE FROM THE PACIFIC WEDNESDAY THROUGH THURSDAY.
HOWEVER, THE ECMWF DOES NOT SHOW THE LEVEL OF COLD TEMPERATURES WE
HAVE HAD LATELY. GIVEN THE PATTERN, HAVE A CHANCE OF RAIN AND SNOW
IN THE MOUNTAINS AND A SLIGHT CHANCE OF RAIN IN THE LOWER ELEVATIONS
MONDAY THROUGH WEDNESDAY. HAVE CARRIED THAT THROUGH WEDNESDAY NIGHT
AND THURSDAY THOUGH HAVE DRIED OUT THE COLUMBIA BASIN. HIGHS WILL
MAINLY BE IN THE 40S WITH 30S IN THE MOUNTAINS SATURDAY THROUGH
WEDNESDAY THEN COOLED IT OFF TO THE MID 30S TO LOWER 40S WITH UPPER
20S TO MID 30S IN THE MOUNTAINS THURSDAY IN CASE THE ECMWF IS RIGHT.
PERRY
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 33 28 45 41 / 60 10 20 90
ALW 35 31 45 41 / 60 10 20 90
PSC 35 27 41 39 / 60 10 20 90
YKM 37 27 39 34 / 60 10 60 90
HRI 34 26 42 39 / 60 10 20 90
ELN 36 26 37 32 / 60 10 70 90
RDM 42 26 45 37 / 40 20 60 90
LGD 40 27 40 36 / 50 20 20 90
GCD 41 27 41 35 / 30 20 20 90
DLS 37 30 38 36 / 30 10 70 90
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...AIR STAGNATION ADVISORY UNTIL NOON PST FRIDAY
ORZ041-044-050-505-507-508-510-511.
WA...AIR STAGNATION ADVISORY UNTIL NOON PST FRIDAY WAZ024-026>029-521.
&&
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
77/97
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
501 PM EST THU NOV 20 2014
.SYNOPSIS...
ARCTIC AIR WILL CONTINUE TO MOVE INTO THE REGION ON A GUSTY WEST
WIND. HIGH PRESSURE WILL BRING MORE TRANQUIL CONDITIONS SATURDAY
BEFORE AN APPROACHING STORM SYSTEM BRINGS A CHANCE OF RAIN SHOWERS
SUNDAY INTO THE FIRST PART OF TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
TEMPS OVER THE LOWER SUSQ VALLEY HAVE MANAGED TO RECOVER INTO THE
MID 40S...BUT COLDER AIR IS MOVING IN AND WILL CONTINUE OVER THE
NEXT 12-24 HOURS.
OTHER THAN SOME SCATTERED FLURRIES OVER WESTERN AND EVEN CENTRAL
AREAS...ANY SIG PRECIP WILL HOLD OFF UNTIL LATER TODAY AND
OVERNIGHT AND WILL EVENTUALLY BECOME FOCUSED OVER OUR LAKE EFFECT
SNOW BELT AREAS OF THE NORTHWEST AND PARTS OF THE LAURELS.
MEAN WIND FROM THE WEST WILL GRADUALLY VEER TO THE WNW THIS
EVENING IN THE WAKE OF A WEAK TROUGH PASSAGE...PUSHING THE SNOW
BAND GRADUALLY SOUTH AND MORE INLAND. LATEST HRRR SHOWS THE SNOW
SLIPPING INTO WARREN-MCKEAN COUNTIES BY AROUND 00Z AND CONTINUING
INTO THE EVENING. SNOW INTENSITIES LATER TONIGHT WILL LIKELY
BECOME LESS IMPRESSIVE AS THE OVER-LAKE TRAJECTORIES
SHORTEN...BUT FORECAST SOUNDINGS SHOW WELL ALIGNED WINDS-LITTLE
WIND SHEAR CONTINUING INTO AT LEAST MID DAY FRIDAY.
HAVEN`T CHANGED THE CONFIGURATION OF THE HEADLINES OR THE
EXPECTED SNOW AMOUNTS SIGNIFICANTLY SINCE OVERALL THINKING HAS NOT
CHANGED.
OVERNIGHT LOWS IN THE TEENS TO AROUND 20 WILL BE WELL BELOW
NORMAL. WIND CHILLS WILL RANGE FROM AROUND ZERO OVER THE
NORTH...TO AROUND 10-15 ABOVE OVER THE SOUTHEAST.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
FRIDAY WILL SEE THE LAKE EFFECT SNOWS GRADUALLY WIND DOWN AS HIGH
PRESSURE BUILDS INTO THE REGION BRINGING LOWERING INVERSION
HEIGHTS. FLURRIES AND EVEN THE POSSIBILITY OF ISOLATED/NARROW
BANDS OF LES BLOWING WELL INLAND ON AN APPROX 310 DEG AXIS MAY
AFFECT THE CENTRAL RIDGE AND VALLEY REGION AND COMMUNITIES ALONG
THE WEST BRANCH OF THE SUSQ RIVER...BUT THIS THREAT WILL WANE AS
WELL AS THE HIGH APPROACHES.
HIGH TEMPS FRIDAY WILL BE VERY SIMILAR...IF NOT A FEW DEGREES COLDER
THAN TODAY.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AN AMPLIFYING UPPER AIR PATTERN WILL BE IN PROGRESS AT THE START
OF THE PERIOD WITH STRONG RIDGES BUILDING TOWARD THE WEST COAST
AND IN THE WESTERN ATLANTIC AND DEEP TROUGHING CARVING OUT OVER
THE CENTRAL U.S BY EARLY NEXT WEEK. GUIDANCE IS TRENDING TOWARD
BETTER AGREEMENT CONCERNING STREAM INTERACTION WHICH IS EXPECTED
TO YIELD A DEEP LOW LIFTING NWD THRU THE TN/OH VLYS INTO THE UPPER
GREAT LAKES BY EARLY MONDAY. A SURGE OF ABNORMALLY WARM/MOIST AIR
AHEAD OF THIS SYSTEM WILL SUPPORT WIDESPREAD PCPN /MOSTLY LKLY IN
THE FORM OF PLAIN RAIN/ SUN-MON BEFORE COLDER CYCLONIC FLOW ALOFT
BEHIND THE TRAILING COLD FRONT BRINGS A DRYING TREND ALONG WITH
COLDER TEMPS BY MIDWEEK.
&&
.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
A GUSTY WEST WIND OF 15-25KT TODAY WILL DIMINISH SOMEWHAT TO
10-20KT OVERNIGHT.
ALL TAF SITES REMAIN VFR AS OF EARLY EVENING...AND SHOULD
CONTINUE THROUGH THE EVENING HOURS. THE POSSIBILITY PERSISTS OF
AN ISOLATED SNOW SHOWER OR TWO BRINGING BRIEFLY REDUCED
CONDITIONS...AS ANY WIDESPREAD SNOW BANDS REMAIN NORTH OF THE
REGION UNTIL LATER TONIGHT.
LATER TONIGHT THE PATTERN WILL SETTLE INTO A MORE FAMILIAR ONE
WHERE MOST OF THE REGION IS VFR WHILE THE HIGHER WESTERN AND
NORTHERN ELEVATIONS HAVE THE BEST CHANCE FOR MVFR WITH OCNL IFR IN
SCATTERED SNOW SHOWERS. BRADFORD STANDS THE HIGHEST CHANCE OF
SIGNIFICANT REDUCTIONS AS LAKE EFFECT SNOW BANDS SETTLE INTO THE
NWRN PART OF THE STATE OVERNIGHT INTO FRIDAY.
SNOW SHOWERS WILL GRADUALLY WIND DOWN AS HIGH PRESSURE BUILDS INTO
THE AREA. BRADFORD WILL LIKELY HOLD ONTO REDUCED CONDITIONS THE
LONGEST AS FLOW OFF THE LAKE CONTINUES TO DRAG MOISTURE AND SNOW
SHOWERS INTO THE NORTHWEST MOUNTAINS...BUT EVEN THERE IMPROVEMENT
IS LIKELY DURING THE AFTERNOON.
OUTLOOK...
SAT...MAINLY VFR.
SUN...MAINLY VFR WITH A CHANCE OF RAIN SHOWERS.
MON...MVFR WITH RAIN SHOWERS.
TUE...MVFR WITH SNOW SHOWERS OVER WESTERN HIGH TERRAIN. VFR
ELSEWHERE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 3 PM EST FRIDAY FOR PAZ005.
LAKE EFFECT SNOW WARNING UNTIL 3 PM EST FRIDAY FOR PAZ004.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...STEINBUGL
AVIATION...LA CORTE/GARTNER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
430 PM EST THU NOV 20 2014
.SYNOPSIS...
ARCTIC AIR WILL CONTINUE TO MOVE INTO THE REGION ON A GUSTY WEST
WIND. HIGH PRESSURE WILL BRING MORE TRANQUIL CONDITIONS SATURDAY
BEFORE AN APPROACHING STORM SYSTEM BRINGS A CHANCE OF RAIN SHOWERS
SUNDAY INTO THE FIRST PART OF TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
TEMPS OVER THE LOWER SUSQ VALLEY HAVE MANAGED TO RECOVER INTO THE
MID 40S...BUT COLDER AIR IS MOVING IN AND WILL CONTINUE OVER THE
NEXT 12-24 HOURS.
OTHER THAN SOME SCATTERED FLURRIES OVER WESTERN AND EVEN CENTRAL
AREAS...ANY SIG PRECIP WILL HOLD OFF UNTIL LATER TODAY AND
OVERNIGHT AND WILL EVENTUALLY BECOME FOCUSED OVER OUR LAKE EFFECT
SNOW BELT AREAS OF THE NORTHWEST AND PARTS OF THE LAURELS.
MEAN WIND FROM THE WEST WILL GRADUALLY VEER TO THE WNW THIS
EVENING IN THE WAKE OF A WEAK TROUGH PASSAGE...PUSHING THE SNOW
BAND GRADUALLY SOUTH AND MORE INLAND. LATEST HRRR SHOWS THE SNOW
SLIPPING INTO WARREN-MCKEAN COUNTIES BY AROUND 00Z AND CONTINUING
INTO THE EVENING. SNOW INTENSITIES LATER TONIGHT WILL LIKELY
BECOME LESS IMPRESSIVE AS THE OVER-LAKE TRAJECTORIES
SHORTEN...BUT FORECAST SOUNDINGS SHOW WELL ALIGNED WINDS-LITTLE
WIND SHEAR CONTINUING INTO AT LEAST MID DAY FRIDAY.
HAVEN`T CHANGED THE CONFIGURATION OF THE HEADLINES OR THE
EXPECTED SNOW AMOUNTS SIGNIFICANTLY SINCE OVERALL THINKING HAS NOT
CHANGED.
OVERNIGHT LOWS IN THE TEENS TO AROUND 20 WILL BE WELL BELOW
NORMAL. WIND CHILLS WILL RANGE FROM AROUND ZERO OVER THE
NORTH...TO AROUND 10-15 ABOVE OVER THE SOUTHEAST.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
FRIDAY WILL SEE THE LAKE EFFECT SNOWS GRADUALLY WIND DOWN AS HIGH
PRESSURE BUILDS INTO THE REGION BRINGING LOWERING INVERSION
HEIGHTS. FLURRIES AND EVEN THE POSSIBILITY OF ISOLATED/NARROW
BANDS OF LES BLOWING WELL INLAND ON AN APPROX 310 DEG AXIS MAY
AFFECT THE CENTRAL RIDGE AND VALLEY REGION AND COMMUNITIES ALONG
THE WEST BRANCH OF THE SUSQ RIVER...BUT THIS THREAT WILL WANE AS
WELL AS THE HIGH APPROACHES.
HIGH TEMPS FRIDAY WILL BE VERY SIMILAR...IF NOT A FEW DEGREES COLDER
THAN TODAY.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AN AMPLIFYING UPPER AIR PATTERN WILL BE IN PROGRESS AT THE START
OF THE PERIOD WITH STRONG RIDGES BUILDING TOWARD THE WEST COAST
AND IN THE WESTERN ATLANTIC AND DEEP TROUGHING CARVING OUT OVER
THE CENTRAL U.S BY EARLY NEXT WEEK. GUIDANCE IS TRENDING TOWARD
BETTER AGREEMENT CONCERNING STREAM INTERACTION WHICH IS EXPECTED
TO YIELD A DEEP LOW LIFTING NWD THRU THE TN/OH VLYS INTO THE UPPER
GREAT LAKES BY EARLY MONDAY. A SURGE OF ABNORMALLY WARM/MOIST AIR
AHEAD OF THIS SYSTEM WILL SUPPORT WIDESPREAD PCPN /MOSTLY LKLY IN
THE FORM OF PLAIN RAIN/ SUN-MON BEFORE COLDER CYCLONIC FLOW ALOFT
BEHIND THE TRAILING COLD FRONT BRINGS A DRYING TREND ALONG WITH
COLDER TEMPS BY MIDWEEK.
&&
.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
A GUSTY WEST WIND OF 15-25KT TODAY WILL DIMINISH SOMEWHAT TO
10-20KT OVERNIGHT.
ALL SITES ARE VFR AS OF EARLY AFTERNOON...AND SHOULD CONTINUE INTO
THE EVENING BUT FOR THE POSSIBILITY OF AN ISOLATED SNOW SHOWER
BRINGING BRIEFLY REDUCED CONDITIONS.
BY LATER TODAY INTO TONIGHT THE PATTERN WILL SETTLE INTO A MORE
FAMILIAR ONE WHERE MOST OF THE REGION IS VFR WHILE THE HIGHER
WESTERN AND NORTHERN ELEVATIONS HAVE THE BEST CHANCE FOR MVFR
WITH OCNL IFR IN SCATTERED SNOW SHOWERS. BRADFORD STANDS THE
HIGHEST CHANCE OF SIGNIFICANT REDUCTIONS AS LAKE EFFECT SNOW BANDS
SETTLE INTO THE NWRN PART OF THE STATE OVERNIGHT INTO FRIDAY.
SNOW SHOWERS WILL GRADUALLY WIND DOWN AS HIGH PRESSURE BUILDS INTO
THE AREA. BRADFORD WILL LIKELY HOLD ONTO REDUCED CONDITIONS THE
LONGEST AS FLOW OFF THE LAKE CONTINUES TO DRAG MOISTURE AND SNOW
SHOWERS INTO THE NORTHWEST MOUNTAINS...BUT EVEN THERE IMPROVEMENT
IS LIKELY DURING THE AFTERNOON.
OUTLOOK...
SAT...MAINLY VFR.
SUN...MAINLY VFR WITH A CHANCE OF RAIN SHOWERS.
MON...MVFR WITH RAIN SHOWERS.
TUE...MVFR WITH SNOW SHOWERS OVER WESTERN HIGH TERRAIN. VFR
ELSEWHERE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 3 PM EST FRIDAY FOR PAZ005.
LAKE EFFECT SNOW WARNING UNTIL 3 PM EST FRIDAY FOR PAZ004.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...STEINBUGL
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
244 PM EST THU NOV 20 2014
.SYNOPSIS...
ARCTIC AIR WILL CONTINUE TO MOVE INTO THE REGION ON A GUSTY WEST
WIND. HIGH PRESSURE WILL BRING MORE TRANQUIL CONDITIONS SATURDAY
BEFORE AN APPROACHING STORM SYSTEM BRINGS A CHANCE OF RAIN SHOWERS
SUNDAY INTO THE FIRST PART OF TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
TEMPS OVER THE LOWER SUSQ VALLEY HAVE MANAGED TO RECOVER INTO THE
MID 40S...BUT COLDER AIR IS MOVING IN AND WILL CONTINUE OVER THE
NEXT 12-24 HOURS.
OTHER THAN SOME SCATTERED FLURRIES OVER WESTERN AND EVEN CENTRAL
AREAS...ANY SIG PRECIP WILL HOLD OFF UNTIL LATER TODAY AND
OVERNIGHT AND WILL EVENTUALLY BECOME FOCUSED OVER OUR LAKE EFFECT
SNOW BELT AREAS OF THE NORTHWEST AND PARTS OF THE LAURELS.
MEAN WIND FROM THE WEST WILL GRADUALLY VEER TO THE WNW THIS
EVENING IN THE WAKE OF A WEAK TROUGH PASSAGE...PUSHING THE SNOW
BAND GRADUALLY SOUTH AND MORE INLAND. LATEST HRRR SHOWS THE SNOW
SLIPPING INTO WARREN-MCKEAN COUNTIES BY AROUND 00Z AND CONTINUING
INTO THE EVENING. SNOW INTENSITIES LATER TONIGHT WILL LIKELY
BECOME LESS IMPRESSIVE AS THE OVER-LAKE TRAJECTORIES
SHORTEN...BUT FORECAST SOUNDINGS SHOW WELL ALIGNED WINDS-LITTLE
WIND SHEAR CONTINUING INTO AT LEAST MID DAY FRIDAY.
HAVEN`T CHANGED THE CONFIGURATION OF THE HEADLINES OR THE
EXPECTED SNOW AMOUNTS SIGNIFICANTLY SINCE OVERALL THINKING HAS NOT
CHANGED.
OVERNIGHT LOWS IN THE TEENS TO AROUND 20 WILL BE WELL BELOW
NORMAL. WIND CHILLS WILL RANGE FROM AROUND ZERO OVER THE
NORTH...TO AROUND 10-15 ABOVE OVER THE SOUTHEAST.
&&
.SHORT TERM /FRIDAY/...
FRIDAY WILL SEE THE LAKE EFFECT SNOWS GRADUALLY WIND DOWN AS HIGH
PRESSURE BUILDS INTO THE REGION BRINGING LOWERING INVERSION
HEIGHTS. FLURRIES AND EVEN THE POSSIBILITY OF ISOLATED/NARROW
BANDS OF LES BLOWING WELL INLAND ON AN APPROX 310 DEG AXIS MAY
AFFECT THE CENTRAL RIDGE AND VALLEY REGION AND COMMUNITIES ALONG
THE WEST BRANCH OF THE SUSQ RIVER...BUT THIS THREAT WILL WANE AS
WELL AS THE HIGH APPROACHES.
HIGH TEMPS FRIDAY WILL BE VERY SIMILAR...IF NOT A FEW DEGREES COLDER
THAN TODAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE BUILDS NE FROM THE OHIO VALLEY LATE FRIDAY INTO
SATURDAY BRINGING CLEARING SKIES AND DIMINISHING WIND.
MORE IN THE WAY OF SUNSHINE AND A WARMING TREND WILL OCCUR ON
SATURDAY...AS THE HIGH BECOMES CENTERED OVER THE MID ATLANTIC
REGION.
A WARM FRONT AND LIMITED MOISTURE RETURN ARRIVING FROM THE OHIO
VALLEY WILL BRING THICKENING CLOUDS AND A CHANCE OF WET SNOW AND
RAIN FOR LATE SAT AND SATURDAY NIGHT.
MILDER TEMPERATURES ARE IN STORE FOR THE LATER PART OF THE
WEEKEND INTO EARLY NEXT WEEK...BUT SOME CHANCE OF SHOWERS INTO
TUE.
DID UP TEMPS SOME...GIVEN RATHER STRONG WARM ADVECTION.
ALSO DID UP POPS SOME FOR SUNDAY NIGHT INTO MONDAY...GIVEN
TYPE OF AIRMASS BEING ADVECTED NORTHWARD.
COOLER AGAIN BY MID WEEK...BUT NOT AS COLD AS WHAT WE HAVE
NOW.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
A GUSTY WEST WIND OF 15-25KT TODAY WILL DIMINISH SOMEWHAT TO
10-20KT OVERNIGHT.
ALL SITES ARE VFR AS OF EARLY AFTERNOON...AND SHOULD CONTINUE INTO
THE EVENING BUT FOR THE POSSIBILITY OF AN ISOLATED SNOW SHOWER
BRINGING BRIEFLY REDUCED CONDITIONS.
BY LATER TODAY INTO TONIGHT THE PATTERN WILL SETTLE INTO A MORE
FAMILIAR ONE WHERE MOST OF THE REGION IS VFR WHILE THE HIGHER
WESTERN AND NORTHERN ELEVATIONS HAVE THE BEST CHANCE FOR MVFR
WITH OCNL IFR IN SCATTERED SNOW SHOWERS. BRADFORD STANDS THE
HIGHEST CHANCE OF SIGNIFICANT REDUCTIONS AS LAKE EFFECT SNOW BANDS
SETTLE INTO THE NWRN PART OF THE STATE OVERNIGHT INTO FRIDAY.
SNOW SHOWERS WILL GRADUALLY WIND DOWN AS HIGH PRESSURE BUILDS INTO
THE AREA. BRADFORD WILL LIKELY HOLD ONTO REDUCED CONDITIONS THE
LONGEST AS FLOW OFF THE LAKE CONTINUES TO DRAG MOISTURE AND SNOW
SHOWERS INTO THE NORTHWEST MOUNTAINS...BUT EVEN THERE IMPROVEMENT
IS LIKELY DURING THE AFTERNOON.
OUTLOOK...
SAT...MAINLY VFR.
SUN...MAINLY VFR WITH A CHANCE OF RAIN SHOWERS.
MON...MVFR WITH RAIN SHOWERS.
TUE...MVFR WITH SNOW SHOWERS OVER WESTERN HIGH TERRAIN. VFR
ELSEWHERE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY FROM 5 PM THIS AFTERNOON TO 3 PM EST
FRIDAY FOR PAZ005.
LAKE EFFECT SNOW WARNING FROM 5 PM THIS AFTERNOON TO 3 PM EST
FRIDAY FOR PAZ004.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/MARTIN
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
554 PM CST FRI NOV 21 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 400 PM CST FRI NOV 21 2014
DIFFICULT LOW CONFIDENCE FORECAST IN THE NEAR TERM. TEMPERATURES
HAVE FINALLY RISEN ABOVE FREEZING IN MOST LOCATIONS ACROSS THE AREA.
THIS HAS PROMOTED AT LEAST A LITTLE BIT OF SNOW MELT. AREA OF
STRATUS THAT HAS BEEN CONTAINED ACROSS MISSOURI AND KANSAS IS NOW
CREEPING NORTHWARD...AND COULD IMPACT PORTIONS OF NORTHWEST IOWA
MAINLY EAST OF THE TAF SITES. ON THE BACK EDGE OF THE STRATUS...
HRRR...RAP AND SREF SUGGEST FOG WILL DEVELOP AFTER 06Z. TRIED TO
KEEP MENTION OF FOG SOUTH OF THE BUFFALO RIDGE WITH STRONG WINDS
LINGERING IN ELEVATED LOCATIONS. KEPT LOWS MILD NORTH OF THE BUFFALO
RIDGE WITH DOWNSLOPE EFFECT. ACROSS THE REST OF THE AREA...SIDED
FAIRLY CLOSE TO CONSENSUS.
STRONG WARMING ALOFT IS EXPECTED THROUGHOUT THE DAY ON
SATURDAY...THE QUESTION REMAINS THOUGH AS TO HOW MUCH OF THAT
WARMING WILL SURFACE. 925 HPA TEMPS WARM THROUGHOUT THE
DAY...STARTING NEAR 3 TO 5 C AND WARMING TO 5 TO 7C BY 00Z SUNDAY.
FOG AND/OR STRATUS MAY LINGER THROUGH THE MORNING HOURS...LIMITING
THE POTENTIAL TO WARM. WHERE THERE IS A VOID OF LOW CLOUDS...SHOULD
SEE SOME NICE WARMING WITH SOUTHWEST FLOW ACROSS THE AREA. STILL
WILL BE FAR FROM FULL MIXOUT...BUT LOOKS TO BE A RELATIVELY MILD DAY
WITH TEMPERATURES ABOVE NORMAL. EXPECT SNOW PACK TO CONTINUE TO
DWINDLE.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 400 PM CST FRI NOV 21 2014
CLOUDS BUILD BACK INTO THE AREA SATURDAY EVENING AND NIGHT AHEAD OF
THE NEXT STORM SYSTEM EXPECTED TO IMPACT THE REGION SUNDAY THROUGH
MONDAY EVENING. SPLIT FLOW WILL KEEP THE AREA LARGELY DRY INTO
SUNDAY AFTERNOON AS THE SOUTHERN STREAM LIFTS A TROUGH NORTHWARD
FROM THE SOUTHERN PLAINS INTO THE MID MISSISSIPPI VALLEY ON SUNDAY
WHILE A TROUGH DIGS INTO THE NORTHERN HIGH PLAINS ALONG THE NORTHERN
STREAM. WITH THE FORECAST AREA STATIONED BETWEEN THESE TWO
AREAS...DRIER CONDITIONS WILL PREVAIL UNDER SOME MID TO HIGH CLOUDS.
A LITTLE LIGHT RAIN POSSIBLY MIXED WITH SOME NORTH IN THE NORTHEAST
MAY CREEP INTO OUR FAR EASTERN BORDER DURING THE DAY. IT LOOKS LIKE
THE BEST SUPPORT FOR ANY WET WEATHER WILL REMAIN EAST OF OF THE
FORECAST AREA. WITH SOMEWHAT BREEZY SOUTHWEST WINDS AND WARMER AIR
ALOFT SATURDAY NIGHT...TEMPERATURES WILL STAY MILD OVERNIGHT WITH
LOWS IN THE 30S. SUNDAY WILL REMAIN MILD AS WINDS TURN NORTHWESTERLY
AND BECOME WINDY BY AFTERNOON. TEMPERATURES WARM INTO THE MID 30S TO
MID 40S BEFORE THE COLD AIR BEGINS LEAKING BACK INTO THE REGION
SUNDAY NIGHT INTO MONDAY.
WITH THE NORTHERN STREAM WAVE SLIDING ACROSS THE NORTHERN PLAINS
SUNDAY EVENING THROUGH MONDAY...SOME LIGHT SNOW WILL SPREAD EAST
ACROSS THE AREA. MOISTURE DOES NOT LOOK TOO IMPRESSIVE WITH THIS
WAVE...HOWEVER SOME DECENT FRONTOGENESIS AND MODEST QG FORCING
SLIDING THROUGH THE AREA WILL ALLOW FOR SOME ISOLATED TO SCATTERED
LIGHT TO FALL. MOST AREAS WILL SEE LESS THAN HALF INCH...BUT COULD
BE A LITTLE HIGHER IN PARTS OF SOUTHWEST MINNESOTA. WITH BLUSTERY
WINDS...ANY SNOW THAT DOES FALL WILL BLOW AROUND...BUT ANY EXISTING
SNOW PACK SHOULD HAVE ENOUGH OF A CRUST TO NOT CAUSE ANY BLOWING
SNOW ISSUES.
MODELS SHOWING BETTER AGREEMENT HEADING INTO THE MIDDLE OF NEXT
WEEK. LEFT A LOW CHANCE FOR LIGHT SNOW MAINLY ACROSS OUR NORTHERN
HALF ON TUESDAY NIGHT AS ANOTHER FRONT DROPS THROUGH THE REGION. DRY
AND COLD WEATHER PERSISTS WEDNESDAY AND THURSDAY...WITH HIGHS
COOLING FURTHER INTO THE MID TEENS TO MID 20S. SHARP RIDGING OVER
THE INTERMOUNTAIN WEST EASES INTO THE PLAINS AND FLATTENS OUT...BUT
TEMPERATURES LOOK MUCH MILDER ON FRIDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 546 PM CST FRI NOV 21 2014
FORECAST REMAINS A CHALLENGE TONIGHT INTO TOMORROW. WATCHING LARGE
AREA OF LOW STRATUS CONTINUE TO PUSH NORTH TOWARDS THE REGION. AM
PRETTY CONFIDENT KSUX WILL GO MVFR BY AROUND 04Z AND EVENTUALLY
IFR LATER TONIGHT. COULD EVEN SEE CIGS DROP INTO THE LIFR
RANGE...WITH DENSE FOG POSSIBLE AS WELL. ALSO PRETTY CONFIDENT
KHON STAYS VFR. LESS CERTAIN ABOUT KFSD...WHICH WILL LIKELY BE
NEAR THE WEST EDGE OF ANY STRATUS AND FOG. BASED ON THE LATEST RAP
AND HRRR DECIDED TO BRING IFR CIGS INTO KFSD LATER
TONIGHT...ALTHOUGH AGAIN CONFIDENCE IS LOW. WHAT IS ALSO UNCERTAIN
IS HOW QUICKLY THE STRATUS AND FOG EXITS TOMORROW. STAYED ON THE
OPTIMISTIC SIDE FOR NOW GIVEN LOW CONFIDENCE...BUT WOULD NOT BE
SURPRISED IF LOW CIGS AND VIS STICK AROUND LONGER THAN CURRENTLY
FORECAST...AS WINDS WILL STAY OUT OF THE SOUTH SOUTHEAST THROUGH
THE DAY.
SO IN SUMMARY...AT THE LEAST THINK NORTHWEST IOWA WILL SEE LOW
STRATUS AND POTENTIALLY DENSE FOG TONIGHT INTO EARLY TOMORROW.
THIS COULD EXTEND AS FAR WEST AS THE INTERSTATE 29 CORRIDOR. FOR
NOW HAVE IMPROVEMENTS BY MID MORNING...BUT THE POSSIBILITY IS
DEFINITELY THERE THAT THESE CONDITIONS LINGER INTO LATE MORNING OR
EVEN EARLY AFTERNOON.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...
LONG TERM...
AVIATION...CHENARD
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
936 PM CST FRI NOV 21 2014
.DISCUSSION...
NO CHANGES TO THIS UPDATE. THE BEST WARM AIR AND MOISTURE
ADVECTION WAS TO THE WEST OF THE FORECAST AREA...GENERALLY ACROSS
THE CENTRAL PART OF THE STATE. THE 00Z NAM12 AND THE HRRR BOTH
KEEP ISOLATED TO SCATTERED RAIN CHANCES OVER THE FAR WESTERN
COUNTIES THROUGH ABOUT 3 AM. CHANCES RETURN BY LATE MORNING ON
SATURDAY.
THE MAIN EVENT STILL LOOKS TO OCCUR SATURDAY AFTERNOON AND
EVENING. THE 00Z NAM12 AND HRRR ARE A BIT SLOWER THAN THE 18Z
TEXAS TECH WRF. THE NAM12 AND HRRR PUSH AN INITIAL LINE OF STORMS
INTO SE TX DURING THE LATE AFTERNOON TO EARLY EVENING TIME PERIOD.
A SQUALL LINE THEN DEVELOPS AND MOVES OVERHEAD LATE EVENING INTO
THE OVERNIGHT PERIOD SATURDAY NIGHT. THE TEXAS TECH WRF IS ABOUT 3
HOURS OR SO QUICKER WITH THE TIMING. AFTER LOOKING OVER THE 00Z
NAMBUFR MODEL SOUNDINGS...THE CURRENT THINKING IS STILL IN LINE
WITH THE PREVIOUS REGARDING THE SEVERE THREAT -- A SLIGHT RISK
FOR SEVERE STORMS WITH DAMAGING WINDS AND HAIL THE MAIN THREATS
AND ISOLATED TORNADOES POSSIBLE.
40
&&
.PREV DISCUSSION... /ISSUED 554 PM CST FRI NOV 21 2014/
DISCUSSION...
00Z TAF DISCUSSION IN AVIATION SECTION.
AVIATION...
COMPLICATED FORECAST FOR AVIATION CONCERNS THE NEXT 24-30HRS.
CIGS TONIGHT SHOULD MOSTLY BE MVFR FOR SE TX TERMINALS. THERE IS
SOME VFR CIGS ALONG THE COAST BUT THOSE SHOULD FILL BACK IN AT
MVFR LEVELS. ONLY QUESTION WILL BE IFR CIGS WHICH LOOK MORE
POSSIBLE OVER KCLL/KUTS/KCXO BUT COULD EASILY DEVELOP OVER THE
HOUSTON AREA IN THE MORNING. MAY NEED TO ADD A TEMPO GROUP FOR IFR
WITH 06Z TAFS SHOULD THERE BE MORE CONFIDENCE IN IFR DEVELOPING.
MVFR CIGS SHOULD REMAIN AND MAY BECOME VFR IN THE AFTERNOON BUT
NOT AS LIKELY. WILL STICK WITH NAM/GFS SOLUTIONS FOR CONVECTIVE
TRENDS AT THIS MOMENT. UPPER LOW OVER AZ SHOULD BE OVER RIO GRANDE
VALLEY NEAR DRT BY 00Z SUN. LEAD SHORTWAVE SHOULD MOVE OVER SE TX
BY THIS TIME OR END OF CURRENT TAF. WAVE MAY INITIATE ONE ROUND OF
TSRA FOR THE AREA. MAIN UPPER LOW THEN MOVES TO ACT/AUS BY 06Z BY
WHICH A 2ND ROUND OF CONVECTION MAY AFFECT THE AREA. ADDED PROB30
GROUP FOR IAH TO ACCOUNT FOR THIS TIMING. OBVIOUSLY TAFS WILL
UNDERGO SEVERAL CHANGES AS THIS SYSTEM EVOLVES BUT THE MAIN
HIGHLIGHT IS TO EXPECT CONVECTION TOMORROW AFTERNOON AND NIGHT TO
DISRUPT AIRPORT OPERATIONS.
39
PREV DISCUSSION... /ISSUED 344 PM CST FRI NOV 21 2014/
DISCUSSION...
SCATTERED LIGHT SHOWERS CONTINUE ACROSS THE REGION THIS AFTERNOON.
GREATEST COVERAGE AND AMOUNTS HAVE BEEN ACROSS OUR WESTERN
COUNTIES THIS AFTERNOON WHERE SOME LOCATIONS HAVE RECEIVED OVER AN
INCH OF RAIN SINCE EARLY THIS MORNING. HAVE SEEN SOME LIGHTNING
WITH THE ACTIVITY JUST OFF TO OUR WEST BUT BEST CHANCES FOR
THUNDER THIS EVENING SHOULD REMAIN BACK ACROSS THE HILL COUNTRY
WHERE THE LOW LEVEL JET WILL SET UP FOR THE NIGHT.
SATURDAY STILL LOOKING TO BE QUITE ACTIVE AS AN UPPER LEVEL STORM
SYSTEM APPROACHES THE REGION. THIS SYSTEM...CURRENTLY OVER
ARIZONA...WILL DIP INTO NORTHERN MEXICO TONIGHT AND APPROACH FROM
THE WEST TOMORROW. A FEW SHOWERS WILL BE POSSIBLE IN THE MORNING
BUT GREATEST CHANCE FOR THUNDERSTORMS WILL BE IN THE AFTERNOON AND
EVENING HOURS ACROSS SOUTHEAST TEXAS. MAIN SEVERE THREAT WILL
CONTINUE TO BE STRONG WINDS AND ISOLATED TORNADOES...PRIMARILY
WITH ANY ISOLATED DISCRETE CELLS WHICH CAN DEVELOP OUT AHEAD OF
THE MAIN AREA OF THUNDERSTORMS WHICH WILL SET UP TO OUR WEST.
EXPECT THIS ACTIVITY TO DEVELOP INTO A LINE BY LATE EVENING AND
PUSH THROUGH THE REGION AFTER SUNSET. BY MIDNIGHT THE ACTIVITY
SHOULD BE MOVING INTO AREAS EAST OF I-45 WITH RAPID DRYING BEHIND
THE LINE. THE ONLY REAL CHANGE FROM THE PREVIOUS FORECAST IS A
TREND TOWARD SLIGHTLY HIGHER RAINFALL TOTALS WHICH MAY PRODUCE
SOME NUISANCE FLOODING ACROSS THE REGION SATURDAY EVENING.
SUNDAY LOOKS TO BE QUITE WARM FOR NOVEMBER WITH HIGHS IN THE MID
70S TO LOW 80S AHEAD OF A COLD FRONT WHICH WILL SWEEP THROUGH THE
REGION EARLY MONDAY MORNING. NO RAIN IS EXPECTED WITH THIS FRONT
OR A SECONDARY FRONT WHICH WILL ARRIVE ON TUESDAY. EXPECT DRY
WEATHER AND SEASONABLE TEMPERATURES FOR THANKSGIVING AND
ASSOCIATED TRAVEL DAYS. 38
MARINE...
SCA CONDITIONS BEYOND 20 NM TONIGHT AND SATURDAY WITH
SLIGHTLY LIGHTER WINDS SCEC FOR THE NEARSHORE WATERS. A PERIOD ON
THE BAYS MAY DEVELOP SATURDAY WHEN SCECS MAY BE NEEDED IN ADVANCE
OF THE BIG STORM SYSTEM COMING THROUGH. STRONG TO SEVERE
THUNDERSTORMS POSSIBLE SAT AFTN/NIGHT WITH ISOLATED WATERSPOUTS
AND GUSTY WINDS THEN IT TRANSITIONS TO SQUALLY CONDITIONS AS THE
SYSTEM ROTATES THROUGH IN THE EVENING AND EARLY MORNING SUNDAY.
COLD FRONT FINALLY COMES THROUGH ENDING THE SOUTHWESTERLY FLOW
TURNING IT TO THE NORTH AND SEAS GRADUALLY SUBSIDE SUNDAY. 45
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 62 74 58 78 47 / 30 90 80 0 0
HOUSTON (IAH) 62 76 61 79 51 / 20 80 90 0 0
GALVESTON (GLS) 65 74 66 78 56 / 20 70 90 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH SATURDAY AFTERNOON
FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL 4 AM CST SUNDAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO
60 NM.
&&
$$
DISCUSSION...40
AVIATION/MARINE...39
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
840 PM CST FRI NOV 21 2014
.UPDATE...
THE LEADING EDGE OF THE PRECIP ACROSS IOWA CONTINUES TO EVAPORATE
AS IT HITS THE VERY DRY AIR IN PLACE ACROSS THE REGION. DEWPOINTS
OVER SOUTHERN WISCONSIN ARE IN THE SINGLE DIGITS TO LOWER TEENS
AND RISE ONLY SLOWLY TO THE SOUTH. IR SATELLITE IMAGERY SHOWS A
NICELY DEFINED MID LEVEL SHORT WAVE OVER IOWA...FCST TO LIFT
ACROSS SRN WISCONSIN TONIGHT...EXITING TO THE EAST BY AROUND 12Z
SATURDAY. THE HRRR RADAR DEPICTION HAS BEEN SHOWING A RATHER
UNIMPRESSIVE PRECIP PATTERN FOR SOUTHERN WISCONSIN OVERNIGHT...
SCATTERED IN COVERAGE AND STAYING MOSTLY SOUTH AND EAST OF
MADISON. THE NEW 00Z NAM IS HEADED THAT WAY AND KEEPS THE BULK OF
THE PRECIP SOUTH OF A DODGEVILLE TO PORT WASHINGTON LINE.
ROAD SENSOR DATA SHOWS PAVEMENT TEMPERATURES GENERALLY IN THE MID
TO UPPER 20S F. AIRCRAFT SOUNDER DATA IS ALREADY SHOWING THE WARM
LAYER ALOFT PUSHING INTO SOUTHERN WISCONSIN...SO THAT SHOULD BE
IN PLACE AND STRONG ENOUGH TO ENSURE THE PRECIP TYPE WILL BE
FREEZING RAIN ONCE THE PRECIP GETS HERE. THE BASE OF THAT LAYER IS
AROUND 3KFT RIGHT NOW.
CONFIDENCE IN THE ADVISORY NORTH OF MADISON IS VERY SHAKY RIGHT
NOW...BUT EVEN A MODERATE AMOUNT OF LIGHT DRIZZLE IN A QUICKLY
MOISTENING BOUNDARY LAYER COULD CAUSE PROBLEMS VERY QUICKLY. THE
ADVISORY LOOKS GOOD SOUTH AND EAST OF MADISON WHERE THERE IS
BETTER CONFIDENCE THERE WILL BE A BIT MORE PRECIP. WILL STAY THE
COURSE FOR NOW OUT OF AN ABUNDANCE OF CAUTION.
TEMPERATURES WILL RISE ABOVE FREEZING SHORTLY AFTER SUNRISE...BUT
PAVEMENT TEMPERATURES MAY LAG THAT AND STILL BE A PROBLEM THROUGH
MID MORNING. THEREAFTER...ALL TEMPS SHOULD SUPPORT RAIN/WET ROADS.
&&
.AVIATION/06Z TAFS/...
LOOK FOR CONDITIONS TO STEADILY DETERIORATE WITH RESPECT TO CIGS
OVERNIGHT. GENERALLY IFR CONDITIONS SHOULD OVERSPREAD THE AREA BY
SUNRISE. AN AREA OF FREEZING RAIN IS EXPECTED ACROSS SOUTHEAST
WISCONSIN...MAINLY BETWEEN ABOUT 2 AM AND 7 AM. AIR TEMPERATURES
THEREAFTER SHOULD BE ABOVE FREEZING...BUT PAVEMENT TEMPERATURES
MAY BE LAGGING BY A FEW HOURS. MADISON MAY ONLY SEE A BRIEF PERIOD
OF FREEZING RAIN AROUND MIDNIGHT WITH PATCHY FREEZING DRIZZLE
POSSIBLE AFTER THAT UNTIL TEMPS WARM ABOVE FREEZING AFTER
SUNRISE.
CIGS MAY BRIEFLY IMPROVE TO MVFR CONDITIONS SATURDAY
AFTERNOON...THEN DROP BACK TO IFR AS MOISTURE STREAMS NORTH INTO
THE AREA AHEAD OF A DEVELOPING LOW PRESSURE TO THE SOUTH AND WEST.
LOW LEVEL WIND SHEAR EXISTS THROUGH ABOUT SUNRISE SATURDAY.
&&
.MARINE...
A SMALL CRAFT ADVISORY CONTINUES THROUGH SUNDAY MORNING DUE TO A
TIGHT PRESSURE GRADIENT BETWEEN HIGH PRESSURE OVER THE EASTERN
GREAT LAKES AND LOW PRESSURE APPROACHING FROM THE NORTHERN PLAINS.
&&
.PREV DISCUSSION... /ISSUED 349 PM CST FRI NOV 21 2014/
SHORT TERM...
TONIGHT...FORECAST CONFIDENCE HIGH.
FREEZING RAIN WILL SPREAD INTO SOUTH CENTRAL WI BY LATE EVENING AND
INTO SOUTHEAST AND EAST CENTRAL WI AROUND MIDNIGHT. THERE IS A
FREEZING RAIN ADVISORY IN EFFECT FOR THE LATE EVENING TO SATURDAY
MORNING HOURS. SOUTHERN WI IS VERY DRY RIGHT NOW WITH SUNSHINE...
BUT THE LOW LEVEL MOISTURE WILL BE ADVECTING INTO THE AREA QUICKLY
THIS EVENING.
WEAK SHORTWAVE ENERGY AND PERSISTENT LOW LEVEL MOISTURE AND WARM AIR
ADVECTION WILL CREATE MODERATE UPWARD MOTION /OMEGA/ OVER SOUTHERN
WI THROUGH MUCH OF THE NIGHT. THE MID LEVELS WILL SATURATE SHORTLY
AFTER THE LOW LEVELS. THIS MEANS WE WILL HAVE A DEEP MOISTURE
PROFILE WITH A WARM LAYER FROM 2 TO 7 KFT WITH A MAX TEMP ALOFT OF
+4C. MEANWHILE... SURFACE TEMPS WILL REMAIN BELOW FREEZING THROUGH
MUCH OF THE NIGHT.
SINCE WE HAVE BEEN IN A COLD PATTERN... BELOW FREEZING FOR THE PAST
10 DAYS... THE GROUND TEMPERATURES ARE BELOW FREEZING. THIS WILL
ALLOW ANY LIQUID TO FREEZE ON CONTACT AND CREATE GLAZED SURFACES.
EXPECT SLIPPERY CONDITIONS ON SIDEWALKS AND UNTREATED ROADS.
THE 12Z MODELS CAME IN WITH SLIGHTLY HIGHER QPF AMOUNTS... SO WE
INCREASED ICE ACCUMULATION AMOUNTS TO UP TO 0.15 INCH IN SOUTHEAST
WI WITH LOWER AMOUNTS ELSEWHERE.
THE UNCERTAINTY FOR TONIGHT IS HOW LOW THE TEMPS WILL DROP AND HOW
LONG THEY WILL REMAIN BELOW FREEZING. THE MODELS ARE STARTING TO
SHOW A SLIGHTLY WARMER TREND. THIS WOULD IMPACT ICE ACCUMULATION
AMOUNTS.
SATURDAY...FORECAST CONFIDENCE HIGH.
TEMPS WILL GRADUALLY WARM ABOVE FREEZING AS THE RAIN TAPERS OFF
SATURDAY MORNING. THE MID LEVELS DRY OUT...BUT THE LOW LEVEL
MOISTURE WILL LINGER THROUGH THE DAY. EXPECT LOW CLOUDS... PERIODS
OF DRIZZLE AND SOME PATCHY FOG WITH TEMPS WARMING INTO THE LOWER
40S.
SATURDAY NIGHT THROUGH TUESDAY...FORECAST CONFIDENCE MEDIUM.
SLY FLOW AND LOW LEVEL WARM...MOIST ADVECTION WILL INCREASE SAT NT
AHEAD OF A TROUGH OF LOW PRESSURE APPROACHING FROM THE PLAINS.
THUS LIGHT RAIN CHANCES AND/OR DRIZZLE WILL INCREASE THROUGHOUT
THE NIGHT. THE RELATIVELY MILD AND MOIST AIR FLOWING OVER A FROZEN
GROUND WILL AID IN SOME FOG DEVELOPMENT.
FOR SUNDAY...A STRONG SHORTWAVE TROUGH OVER E TX WILL LIFT NEWD
TO THE OHIO RIVER VALLEY BY 00Z MON WHILE A LARGER SCALE UPPER
TROUGH MOVES EWD ACROSS THE NRN PLAINS. STRONG CYCLOGENESIS WILL
RESULT FROM CENTRAL IL TO ERN UPPER MI FROM SUN AFTERNOON THROUGH
12Z MON. THE STRONG LOW WILL TRACK NORTH OVER WRN LOWER MI WITH
PWS INCREASING TO ONE INCH OVER WI. THE DEEP QG DYNAMICS AND
FRONTOGENESIS WILL LEAD TO WIDESPREAD MDT RAIN FOR SUN AFTERNOON
AND NIGHT. AS THE RAIN DIMINISHES LATE SUN NT AND EARLY MON AM...A
CHANGE TO LGT SNOW IS EXPECTED WITH LITTLE TO NO SNOW
ACCUMULATION. THE AFOREMENTIONED UPPER TROUGH TO THE WEST WILL
THEN PASS MON AFTERNOON AND NIGHT WITH A SECONDARY COLD FRONT FOR
MON NT. THIS WILL BRING CONTINUED CHANCES OF LGT SNOW THAT COULD
LINGER INTO TUE AM OVER ERN WI. OVERALL RAINFALL DURING THIS TIME
SHOULD REACH ONE INCH.
LONG TERM...TUESDAY AFTERNOON THROUGH FRIDAY...FORECAST
CONFIDENCE MEDIUM.
HIGH PRESSURE WILL SETTLE OVER THE AREA BY LATE TUE INTO WED AM. A
LARGE SCALE UPPER TROUGH WILL THEN DIG SEWD FROM CANADA...INTO THE
GREAT LAKES AND EVENTUALLY ALL OF THE ERN USA. THIS WILL BRING
CHANCES OF LIGHT SNOW WED AND WED NT WITH STRONG COLD ADVECTION TO
FOLLOW. POLAR HIGH PRESSURE THEN EXPECTED BY LATE THU INTO FRI
WITH VERY COLD TEMPS ONCE AGAIN.
AVIATION/00Z TAFS/...LOW LEVEL CLOUDS WILL MOVE IN FROM THE SOUTHWEST
THIS EVENING. CEILINGS WILL DROP TO MVFR LATE THIS EVENING AT MSN
AND AROUND MIDNIGHT AT EASTERN TAF SITES...AN HOUR OR TWO AHEAD OF
FREEZING RAIN ONSET. EXPECTING FREEZING RAIN TO START AT MSN
AROUND MIDNIGHT AND AN HOUR LATER AT EASTERN TAF SITES. THE
MAJORITY OF THE FREEZING RAIN SHOULD END AROUND SUNRISE SATURDAY.
EXPECTING UP TO 0.15 INCHES OF ICE ACCUMULATION AT MKE AND ENW AND
UP TO 0.10 AT MSN AND UES. HIGH CONFIDENCE OF AT LEAST SOME ICE
ACCUMULATION AT ALL TAF SITES. WINDS AT 2000 FT EXPECTED TO BE 40
TO 45 KTS DURING THE NIGHT. NO MENTION OF WIND SHEAR WITH GUSTS UP
TO 20 KTS EXPECTED AT THE SURFACE.
PATCHY DRIZZLE OR PATCHY FREEZING RAIN EXPECTED FOR A COUPLE HOURS
AFTER SUNRISE SATURDAY BEFORE A CHANGEOVER TO PATCHY DRIZZLE DURING
THE LATE MORNING. PATCHY DRIZZLE EXPECTED TO CONTINUE THROUGH THE
DAY WITH CEILINGS UNDER 1000 FT POSSIBLE LATE SATURDAY AFTERNOON AND
INTO THE EVENING. SOME UNCERTAINTY WITH THE TIMING OF THESE LOWER
CEILINGS.
MARINE...THE SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 6 AM SUNDAY. A
TIGHT PRESSURE GRADIENT WILL DOMINATE THE REGION WITH HIGH PRESSURE
TO THE SOUTHEAST AND LOW PRESSURE TO THE NORTHWEST. FREEZING RAIN
EXPECTED AFTER MIDNIGHT THROUGH SUNRISE WITH DRIZZLE DURING THE DAY
ON SATURDAY.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...FREEZING RAIN ADVISORY UNTIL 9 AM CST SATURDAY FOR WIZ046-047-
056-057-062-063-067>069.
FREEZING RAIN ADVISORY FROM 1 AM TO 10 AM CST SATURDAY FOR
WIZ051-052-058>060-064>066-070>072.
LM...SMALL CRAFT ADVISORY UNTIL 6 AM CST SUNDAY FOR LMZ643>646.
&&
$$
UPDATE...DAVIS
TONIGHT/SATURDAY AND AVIATION/MARINE...SM
SATURDAY NIGHT THROUGH FRIDAY...GEHRING
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1052 PM MST WED NOV 19 2014
.UPDATE...
ISSUED AT 854 PM MST WED NOV 19 2014
FORECAST IN GOOD SHAPE THIS EVENING WITH NO ONGOING IMPACTS.
SATELLITE IMAGES SHOW MID/HIGH-LEVEL CLOUDS NOW CONFINED ONLY TO
SRN CARBON COUNTY. OTHERWISE...SKIES ARE VIRTUALLY CLEAR ACROSS
THE ENTIRE CWFA. THE ONLY CHANGE TO THE FORECAST WAS TO COOL
CHADRON/ALLIANCE OVERNIGHT LOWS A FEW DEGREES AND TO ADD PATCHY
FOG TO AREAS NORTH OF THE PINE RIDGE. LATEST HRRR SHOWS AND FAIRLY
WELL DEFINED AREA OF LOW CLOUDS/FOG FROM NRN NIOBRARA COUNTY
SOUTHEAST INTO NRN HARRISON AND DAWES COUNTIES LATE TONIGHT AND
TOMORROW MORNING. NOT SURE THE EXTENT OF THE FOG...BUT COULDNT
IGNORE THIS SHORT RANGE SIGNAL. OTHERWISE...A QUIET NIGHT AHEAD.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 214 PM MST WED NOV 19 2014
FAIRLY TRANQUIL WEATHER EXPECTED ACROSS THE CWA FOR MOST OF THIS
PERIOD WITH TEMPERATURES RATHER MILD THROUGH SATURDAY. THIS
COMPLIMENTS OF AN UPPER RIDGE INITIALLY TO THE WEST THAT WILL MOVE
EAST ACROSS THE CWA WHILE WEAKENING OVER THE NEXT COUPLE DAYS.
WINDS WILL BE GENERALLY MODEST THROUGH FRIDAY. A WEAK IMPULSE WILL
CROSS THE CENTRAL ROCKYS LATE THURSDAY AND COULD BRING A FEW SNOW
SHOWERS TO THE HIGHER MTNS AT THAT TIME WITH A ZONAL FLOW SETTING
UP OVER THE REGION BEHIND IT FOR FRIDAY. BY LATE FRIDAY A LEE
TROUGH IS EXPECTED TO DEVELOP AND DEEPEN OVER THE HIGH PLAINS
WHICH WILL INITIATE AN INCREASE IN WINDS AROUND THE MOUNTAINS LATE
THAT EVENING...A PRECURSOR OF MORE WIND TO COME.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY)
ISSUED AT 214 PM MST WED NOV 19 2014
STRONG WINDS ARE GOING TO BE THE MAIN FORECAST CHALLENGE THROUGH
MUCH OF THE EXTENDED PERIOD.
STARTING OFF SATURDAY...WEAK SHORTWAVE AND ASSOCIATED COLD FRONT
MOVE THROUGH THE AREA THROUGH THE DAY SATURDAY WITH SNOW SHOWERS
MAINLY CONFINED TO THE SNOWY AND SIERRA MADRE RANGES. AFTER A
FAIRLY WARM DAY SATURDAY...GFS 700MB TEMPERATURES FALL FROM 0
TO+2C SATURDAY AT NOON...DOWN TO -8 TO-10C SUNDAY MORNING. GOING
TO BE PRETTY WINDY ONCE THE FRONT MOVES THROUGH THE AREA SATURDAY
AFTERNOON. GFS 700MB WINDS PRETTY CLOSE TO 45-50KTS BEHIND THE
FRONT WITH 850MB WINDS 35 TO 40KTS OUT IN THE PANHANDLE. 700MB
CRAIG TO CASPER GRADIENTS PRETTY STRONG THROUGH THE DAY
SATURDAY...STARTING OFF AROUND 990MTRS SATURDAY MORNING...EASING
TO 60MTRS SATURDAY NIGHT. WIND HEADLINES FOR THE WIND PRONE AREAS
AT LEAST LOOKS LIKE A CERTAINTY.
LOOKS LIKE A SLIGHT REPRIEVE SUNDAY AS THE JET DIVES SOUTH INTO
SOUTHERN COLORADO AND INTO NEW MEXICO. 700MB WINDS EASE TO
20-30KTS THROUGH THE DAY SUNDAY. WINDY AREA LOOKS TO BE THE
PANHANDLE WHERE 850MB WINDS ARE STILL FORECAST AT 35-40KTS THROUGH
THE DAY.
A MUCH MORE WIDESPREAD AND STRONGER WIND EVENT SUNDAY
NIGHT...PERSISTING INTO PROBABLY WEDNESDAY NEXT WEEK. HAVE A
SHORTWAVE TRACKING THROUGH MONTANA AND INTO EASTERN WYOMING LATE
SUNDAY NIGHT INTO MONDAY AROUND THE LOW OVER THE GREAT LAKES.
THIS DRAGS A BACKDOOR COLD FRONT INTO THE NORTHERN PANHANDLE AND
NORTHEAST WYOMING BY MONDAY AFTERNOON. OUT WEST IN CARBON AND
ALBANY COUNTIES...700MB WINDS ARE INITIALLY 50+KTS MONDAY
MORNING. THEN EASE SOME DURING THE LATE MORNING.
BY LATE MONDAY AFTERNOON...UPPER SHORTWAVE PASSES TO THE SOUTHEAST
WITH THE LONGWAVE RIDGE BUILDING INTO THE AREA. LOOKING AT 60 TO
80 MTR HEIGHT RISES AT 500MB AS THE RIDGE BUILDS INTO SOUTHEAST
WYOMING. 700MB WINDS OF 50 TO 60KTS MONDAY EVENING OUT OF THE
NORTHWEST.
BY TUESDAY AFTERNOON...WINDS TURN MORE WESTERLY AND REALLY BEGIN
TO INCREASE. GFS WINDS TUESDAY AFTERNOON APPROACHING 70KT ACROSS
THE WESTERN HALF OF THE CWFA WITH 90+MTR 700MB CRAIG TO CASPER
GRADIENTS FORECAST. BY WEDNESDAY MORNING...700MB WINDS INCREASE TO
80KTS OVER LARAMIE AND 700MB CRAIG TO CASPER GRADIENTS NEAR
120MTRS. SHOULD SEE WIDESPREAD HIGH WIND HEADLINES IF THIS COMES
TRUE FOR BOTH TUESDAY AND WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1042 PM MST WED NOV 19 2014
VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. THE ONLY EXCEPTION
WILL BE THE POSSIBILITY OF LOW STRATUS/FOG DEVELOPMENT AT KCDR.
LATEST SHORT RANGE MODELS HINT AT LEAST THE POSSIBILITY FOR ITS
DEVELOPMENT. AM NOT ENTIRELY CONFIDENT BUT DID ADD VCFG AND A
SCT010 DECK TO THE TAF. OTHERWISE...WINDS WILL VARY FROM
NORTHWEST TO SOUTHWEST AT MOST AREA TERMINALS THROUGH THE PERIOD
AND RELATIVELY LIGHT (LESS THAN 10 KNOTS). THE EXCEPTION WILL BE
AT KRWL AFTER 16Z THURSDAY WHERE GUSTS TO 25 KNOTS ARE EXPECTED.
&&
.FIRE WEATHER...
ISSUED AT 214 PM MST WED NOV 19 2014
NO CONCERNS ANTICIPATED FOR THE REST OF THE WEEK INTO THE WEEKEND
WITH WEATHER FACTORS EXPECTED TO BE NON-CRITICAL. BY LATE SATURDAY
ONWARD INTO NEXT WEEK STRONG WINDS WILL RETURN TO AREAS ESPECIALLY
AROUND THE MOUNTAINS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...CAH
SHORT TERM...RE
LONG TERM...GCC
AVIATION...CAH
FIRE WEATHER...RE
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
445 AM EST SAT NOV 22 2014
.DISCUSSION...
...ROUGH BOATING/BEACH CONDITIONS WITH INCREASING RAIN CHANCES...
CURRENT...
LARGE/STRONG HIGH PRESSURE RIDGE CENTERED OVER THE MIDDLE ATLC
REGION CONTINUES TO PRODUCE STOUT ONSHORE FLOW ACROSS ECFL AND THE
ADJCT ATLC. OLD FRONTAL BOUNDARY REMAINS QSTNRY TO OUR SOUTH...OVER
THE FL STRAITS. A WEAK MID LEVEL SHEAR AXIS EXTENDING FROM THE GOMEX
ACROSS THE CTRL PENINSULA IS SLOWLY LIFTING NWD. RAOB/PROFILER DATA
SHOW SWRLY FLOW AOA 6-7KFT PRODUCING WAA/ISENTROPIC UPGLIDE AND
EXTENSIVE MID LEVEL CLOUDS...ALONG WITH PASSING SPRINKLES OF LIGHT
RAIN. THERE REMAINS SOME RESIDUAL DRY AIR ABOVE H60 AND BELOW H80...
WITH HIGH MEAN RH VALUES IN BETWEEN.
TODAY/TONIGHT...
THE LARGE SURFACE HIGH TO THE NORTH WILL SHIFT EAST AND OFFSHORE
INTO THE ATLC OVER THE NEXT H24 AS THE BASE OF A MID LEVEL SHORT
WAVE TROUGH UPSTREAM MOVES OVER THE NERN GOMEX/GULF COAST...WITH
SOME MID LEVEL VORTICITY REACHING THE BIG BEND AREA. COMBINATION OF
THESE TWO FEATURES WILL CAUSE GRADUAL VEERING OF WINDS IN THE
SFC-H85 FROM ENE-E TO SE AND S...WITH BACKING OF THE H70-H50 FLOW
FROM WSW TO SW. THIS WILL CAUSE THE OLD BOUNDARY TO LIFT BACK NWD AS
A WARM FRONT....ADVECTING THE HIGHER MEAN PWAT AIR MASS LURKING TO
OUR SOUTH BACK NWD ACROSS OUR AREA. EXPECT ALREADY CLOUDY SKIES TO
REMAIN SO...THICKENING IN THE PROCESS. AREAS OF LIGHT RAIN WITH
EMBEDDED MODERATE TO HEAVIER SHOWERS WILL DEVELOP...WITH SOME BANDED
MARINE ACTIVITY ALSO LIKELY TO FACTOR INTO THE SENSIBLE WX ALONG THE
SPACE/TREASURE COASTS BY THIS AFTERNOON. BEST LIFT AND BETTER RAIN
CHANCES WILL LIFT NWD WITH THE FRONT...REACHING NORTH FL BY SUNDAY
MORNING.
OVERALL...CONDITIONS LOOK CLOUDY/DAMP BUT WARM. NOT A HUGE DIURNAL
RANGE GIVEN THE EXTENSIVE CLOUD COVER. MAXES GENERALLY IN THE M-U70S
WITH LOWS IN THE U60S-L70S.
SUN-MON...
AN UNSETTLED WX PD TO START THE UPCOMING WEEK. THE LARGE HI PRES
RIDGE BLANKETING THE ERN CONUS WILL PUSH INTO THE ATLC AS A DVLPG
STORM SYSTEM OVER THE PAC NW DRIFTS ALONG THE CANADIAN BORDER. THE
H30-H20 JET PATTERN OVER THE ERN PAC IS ALMOST PERFECTLY ZONAL...
WITH A 150KT MAX THAT WILL SERVE TO STRENGTHEN THE NEW SFC LOW AS IT
CROSSES THE CANADIAN ROCKIES. THE JET STREAK WILL AMPLIFY AS PUSHES
INTO THE PAC NW...BUT EXISTING ZONAL FLOW WILL PUSH THE STORM SYSTEM
TOO FAR TO THE EAST TOO QUICKLY FOR IT TO DROP MUCH BELOW THE NRN
PLAINS BEFORE IT GETS CAUGHT UP BY THE LIFTING SIDE OF THE UPR LVL
SHORT WAVE AND BOMBS OUT OVER THE GREAT LAKES BY DAYBREAK MON. BY
THEN...THE AFOREMENTIONED HI PRES RIDGE WILL HAVE ANCHORED ITSELF
OVER THE W ATLC...WHERE IT WILL DEFLECT THE STORM SYSTEM INTO ERN
CANADA BY DAYBREAK TUE. THE SRN EXTENT OF THE TRAILING COLD FRONT
WILL BE LEFT TO ITS OWN MOMENTUM FOR FORWARD PROGRESS...WHICH WILL
BE SLOW GIVEN THE POSITION OF THE ATLC RIDGE.
H100-H70 WINDS WILL VEER TO THE S/SW THRU THE DAY ON SUN AS THE
RIDGE BUILDS OFFSHORE...WHILE AN H85-H50 ANTICYCLONE OVER THE NRN
BAHAMAS WILL MAINTAIN AN EXISTING W/SW FLOW THRU THE MID LYRS. THIS
WILL RESULT IN STRONG LOW/MID LVL ISENTROPIC LIFT IN THE PRESENCE OF
LOW LVL MOISTURE ADVECTION. MID LVL MOISTURE...HOWEVER...WILL BE ON
THE WANE AS LATEST RUC ANALYSIS SHOWS H85-H50 MEAN RH VALUES
DECREASING FROM 60-70PCT OVER CENTRAL/SOUTH FL...TO BLO 50PCT OVER
THE NW CARIB.
THE COMBINATION OF LOW LVL MOISTURE AND MID LVL DRY AIR WILL SET THE
STAGE FOR TSTM DEVELOPMENT THRU MON...ESPECIALLY AS THE STORM SYSTEM
DVLPS AND TRIES TO CRANK A NEW COLD FRONT THROUGH THE DEEP SOUTH.
HOWEVER...PROGRESS OF THE FRONT WILL BE SLOW AS THE ATLC RIDGE
BLOCKS ITS ADVANCE WHILE THE THE STORM SYSTEM LIFTS INTO CANADA AND
ABANDONS THE SRN EXTENT OF ITS TROF. A BRISK S/SW BREEZE WILL
PREVAIL THRU THE H100-H70...ADDING WARM AIR ADVECTION TO THE
PICTURE. ONE MAJOR FACTOR THAT WILL WORK AGAINST A STRONG/SVR WX
EVENT WILL BE THE THERMAL PROFILE. THE -10C H50 ISOTHERM IS
CURRENTLY LOCATED N OF THE I-4 CORRIDOR AND WILL ONLY LIFT FURTHER
NORTH IN THE FACE OF THE MID LVL SWRLY FLOW. H70-H50 LAPSE RATES
OVER THE CENTRAL GOMEX ARE RUNNING A RESPECTABLE 6.5-7.0C/KM...BUT A
PALTRY AOB 5C/KM THRU THE H85-H70 LYR.
WILL OPT FOR CHC/LIKELY SHRAS AND A SLGT CHC OF TSTMS ON SUN...
HIGHEST OVER THE NRN CWA DUE TO A DEEPER MOISTURE PROFILE. POPS
DECREASING TO CHC/SLGT CHC SUN NIGHT AS DRIER AIR AND THE LOSS OF
DIURNAL HEATING SHOULD CHOKE OFF MOST OF ANY STORM ACTIVITY. AS THE
FRONT STALLS OVER THE FL BIG BEND/ERN PANHANDLE...THE DEEPEST
MOISTURE WILL POOL TO THE N...WHILE MID/UPR LVL DEBRIS CLOUDS
DISTURB SFC HEATING/LOW LVL DESTABILIZATION. POPS WILL RANGE FROM
40PCT FROM SRN LAKE/ORANGE/NRN BREVARD NWD...TO 20PCT N/E FROM LAKE
OKEECHOBEE. SRLY FLOW WILL PUSH TEMPS WELL ABV AVG...MAXES INTO THE
L/M80S AND MIN IN THE M/U60S.
TUE-FRI...
WET WX PATTERN WILL CONTINUE THRU MID WEEK AS THE UPR LVL JET
PATTERN BECOMES HIGHLY AMPLIFIED ACRS THE CONUS. JET ENERGY OVER THE
W PAC IS PLENTIFUL WITH H25 WINDS ARND 150KTS ENCROACHING ON THE
OREGON COAST. AS THIS JET DIGS INTO THE NW CONUS AND ITS ENERGY IS
TRANSLATED DOWNSTREAM...THE LIFTING JET OVER THE ERN CONUS WILL
STRENGTHEN CONSIDERABLY...THE 00Z GFS MODEL SUGGESTING MAX SPEEDS
ARND 200KTS DVLPG OVER NEW ENGLAND LATE TUE NIGHT WITH THE 150KT
ISOTACH TRAILING INTO THE DEEP SOUTH. THE STRONG UPR LVL DIVERGENCE
GENERATED BY THIS JET WILL INDUCE A NEW AREA OF LOW PRESSURE N OF
THE BAHAMA BANK DAYBREAK WED ALONG OR JUST AHEAD OF THE STALLED
FRONTAL BNDRY.
AS THE LOW DLVPS AND LIFTS UP THE ERN SEABOARD...IT WILL DRAG THE
FRONT CLEAR OF THE STATE...ALLOWING A DRY WX PD TO PREVAIL THRU THE
LATTER HALF OF THE WEEK. THE 22/00Z ECMWF INDICATES THIS HAPPENING
BY 00Z THU...22/00Z GFS ABOUT 12HRS SLOWER. WITH THE FRONT SAGGING
INTO CENTRAL FL ON TUE...WILL NEED TO PAINT THE AREA WITH LKLY POPS.
POPS DIMINISHING FROM THE W ON WED BUT REMAINING BTWN 30-50PCT...
20-30PCT...LINGERING ALONG THE COAST/LAKE OKEECHOBEE THRU WED NIGHT.
DRY WX FCST THU-FRI.
TUE TEMPS WILL REFLECT THE POSITION OF THE FRONT...MAXES RANGING
FROM THE L70S N OF I-4 TO THE L80S E OF LAKE OKEECHOBEE...MINS FROM
THE L50S TO L60S RESPECTIVELY. COOL/DRY AIR ADVECTION BEHIND THE
FRONT WILL DROP MAX TEMPS INTO THE 60S AREAWIDE ON WED...MINS INTO
THE L40S-L50S WED NIGHT. LITTLE TEMP CHANGE EXPECTED THRU FRI AS A
SLOW MOVING HI PRES BEHIND THE FRONT WILL MAINTAIN A STEADY N/NW
FLOW.
&&
.AVIATION...
VFR WITH CIGS OVC-BKN040-060 MLB-SUA AND OVC080-110 KTIX-KMCO NWD.
CIGS WILL LOWER/THICKEN WITH MVFR CONDS DEVELOPING/SPREADING NWD
FROM SUA-FPR. EVENTUALLY EXPECT TO SEE SOME IFR TO LOW END MVFR CIGS
BKN-OVC007-015 BECOME PREVALENT STARTING IN THE 22Z-02Z TIME FRAME.
&&
.MARINE...
TODAY/TONIGHT...THE STRONG HIGH TO THE NORTH WILL MAINTAIN THE TIGHT
LOCAL PGRAD WITH WINDS 20-25KT AND SEAS ALREADY A SOLID 7-9FT ACROSS
THE ENTIRETY OF THE MAOR. WNAWAVE GUIDANCE IS UNDERDOING CURRENT
CONDITIONS BY A GOOD 1-2FT...AND THE NWPS LOOKS MUCH CLOSER TO
REALITY. SEAS UP TO 8FT NEAR SHORE AND 10FT OFFSHORE. HEIGHT OF THE
BREAKERS IN THE SURF ZONE LOOK TO BE A LITTLE SHORT OF HIGH SURF ADV
CRITERIA...NEVERTHELESS LARGE BREAKING WAVES/HIGH SEAS WILL PRODUCE
VERY HAZARDOUS CONDITIONS FOR SMALL CRAFT...AND DANGEROUS SWIMMING/
SURF FOR BEACH GOERS...WITH NUMEROUS STRONG RIPS AND POSSIBLE MINOR
EROSION AROUND THE TIME OF HIGH TIMES.
SUN-MON...UNFAVORABLE CONDITIONS TO START THE WEEK AS A MODERATE TO
FRESH S/SE BREEZE CONTINUES THRU THE DAY ON SUN...SEAS 5-7FT
NEARSHORE AND 8-10FT OFFSHORE. SFC/BNDRY LYR WINDS BCMG GENTLE TO
MODERATE S/SW ON MON AS A COLD FRONT STALLS OVER THE FL PANHANDLE...
SEAS SUBSIDING TO 3-4FT NEARSHORE AND 5-7FT OFFSHORE.
TUE-TUE NIGHT...COLD FRONT WILL SAG INTO CENTRAL FL...RESULTING IN
VRBL WINDS ACRS THE LCL ATLC...S/SE 10-15KTS AHEAD OF THE FRONT...
N/NW 5-10KTS BEHIND IT. WINDS WILL FRESHEN OUT OF THE N/NW AFT
SUNSET AS A WEAK LOW PRES SYSTEM DVLPS N OF THE BAHAMAS...MODERATE
TO FRESH N OF SEBASTIAN INLET...GENTLE TO MODERATE S OF THE INLET.
SEAS 3-5FT N OF THE INLET AND 2-4FT S OF THE INLET THRU THE
DAY...BUILDING TO 5-7FT N OF THE INLET AND 3-5FT S OF THE INLET AFT
SUNSET.
WED-WED NIGHT...FRESH TO STRONG NW BREEZE WILL DVLP SHORTLY AFT
SUNRISE AS THE LOW PRES SYSTEM LIFTS N AND DRAGS THE COLD FRONT THRU
THE ATLC WATERS. SEAS BUILDING TO 6-8FT NEARSHORE AND 7-9FT OFFSHORE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 73 69 81 68 / 50 60 60 40
MCO 76 67 83 68 / 50 60 60 40
MLB 76 73 82 70 / 50 50 50 30
VRB 77 74 82 70 / 50 50 50 30
LEE 75 66 83 68 / 50 60 60 40
SFB 75 67 83 67 / 50 60 60 40
ORL 76 68 83 68 / 50 60 60 40
FPR 78 74 82 70 / 50 50 40 30
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 4 PM EST SUNDAY FOR COASTAL WATERS
FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE OUT 20 NM-
COASTAL WATERS FROM SEBASTIAN INLET TO JUPITER INLET OUT 20
NM-COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO
SEBASTIAN INLET OUT 20 NM-WATERS FROM FLAGLER BEACH TO
VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS
FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE-
WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET
20 TO 60 NM OFFSHORE.
&&
$$
SHORT TERM/AVIATION...CRISTALDI
LONG TERM/IMPACT WX...BRAGAW
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
350 AM EST SAT NOV 22 2014
.DISCUSSION...
...ROUGH BOATING/BEACH CONDITIONS WITH INCREASING RAIN CHANCES...
CURRENT...
LARGE/STRONG HIGH PRESSURE RIDGE CENTERED OVER THE MIDDLE ATLC
REGION CONTINUES TO PRODUCE STOUT ONSHORE FLOW ACROSS ECFL AND THE
ADJCT ATLC. OLD FRONTAL BOUNDARY REMAINS QSTNRY TO OUR SOUTH...OVER
THE FL STRAITS. A WEAK MID LEVEL SHEAR AXIS EXTENDING FROM THE GOMEX
ACROSS THE CTRL PENINSULA IS SLOWLY LIFTING NWD. RAOB/PROFILER DATA
SHOW SWRLY FLOW AOA 6-7KFT PRODUCING WAA/ISENTROPIC UPGLIDE AND
EXTENSIVE MID LEVEL CLOUDS...ALONG WITH PASSING SPRINKLES OF LIGHT
RAIN. THERE REMAINS SOME RESIDUAL DRY AIR ABOVE H60 AND BELOW H80...
WITH HIGH MEAN RH VALUES IN BETWEEN.
TODAY/TONIGHT...
THE LARGE SURFACE HIGH TO THE NORTH WILL SHIFT EAST AND OFFSHORE
INTO THE ATLC OVER THE NEXT H24 AS THE BASE OF A MID LEVEL SHORT
WAVE TROUGH UPSTREAM MOVES OVER THE NERN GOMEX/GULF COAST...WITH
SOME MID LEVEL VORTICITY REACHING THE BIG BEND AREA. COMBINATION OF
THESE TWO FEATURES WILL CAUSE GRADUAL VEERING OF WINDS IN THE
SFC-H85 FROM ENE-E TO SE AND S...WITH BACKING OF THE H70-H50 FLOW
FROM WSW TO SW. THIS WILL CAUSE THE OLD BOUNDARY TO LIFT BACK NWD AS
A WARM FRONT....ADVECTING THE HIGHER MEAN PWAT AIR MASS LURKING TO
OUR SOUTH BACK NWD ACROSS OUR AREA. EXPECT ALREADY CLOUDY SKIES TO
REMAIN SO...THICKENING IN THE PROCESS. AREAS OF LIGHT RAIN WITH
EMBEDDED MODERATE TO HEAVIER SHOWERS WILL DEVELOP...WITH SOME BANDED
MARINE ACTIVITY ALSO LIKELY TO FACTOR INTO THE SENSIBLE WX ALONG THE
SPACE/TREASURE COASTS BY THIS AFTERNOON. BEST LIFT AND BETTER RAIN
CHANCES WILL LIFT NWD WITH THE FRONT...REACHING NORTH FL BY SUNDAY
MORNING.
OVERALL...CONDITIONS LOOK CLOUDY/DAMP BUT WARM. NOT A HUGE DIURNAL
RANGE GIVEN THE EXTENSIVE CLOUD COVER. MAXES GENERALLY IN THE M-U70S
WITH LOWS IN THE U60S-L70S.
SUN-MON...
AN UNSETTLED WX PD TO START THE UPCOMING WEEK. THE LARGE HI PRES
RIDGE BLANKETING THE ERN CONUS WILL PUSH INTO THE ATLC AS A DVLPG
STORM SYSTEM OVER THE PAC NW DRIFTS ALONG THE CANADIAN BORDER. THE
H30-H20 JET PATTERN OVER THE ERN PAC IS ALMOST PERFECTLY ZONAL...
WITH A 150KT MAX THAT WILL SERVE TO STRENGTHEN THE NEW SFC LOW AS IT
CROSSES THE CANADIAN ROCKIES. THE JET STREAK WILL AMPLIFY AS PUSHES
INTO THE PAC NW...BUT EXISTING ZONAL FLOW WILL PUSH THE STORM SYSTEM
TOO FAR TO THE EAST TOO QUICKLY FOR IT TO DROP MUCH BELOW THE NRN
PLAINS BEFORE IT GETS CAUGHT UP BY THE LIFTING SIDE OF THE UPR LVL
SHORT WAVE AND BOMBS OUT OVER THE GREAT LAKES BY DAYBREAK MON. BY
THEN...THE AFOREMENTIONED HI PRES RIDGE WILL HAVE ANCHORED ITSELF
OVER THE W ATLC...WHERE IT WILL DEFLECT THE STORM SYSTEM INTO ERN
CANADA BY DAYBREAK TUE. THE SRN EXTENT OF THE TRAILING COLD FRONT
WILL BE LEFT TO ITS OWN MOMENTUM FOR FORWARD PROGRESS...WHICH WILL
BE SLOW GIVEN THE POSITION OF THE ATLC RIDGE.
H100-H70 WINDS WILL VEER TO THE S/SW THRU THE DAY ON SUN AS THE
RIDGE BUILDS OFFSHORE...WHILE AN H85-H50 ANTICYCLONE OVER THE NRN
BAHAMAS WILL MAINTAIN AN EXISTING W/SW FLOW THRU THE MID LYRS. THIS
WILL RESULT IN STRONG LOW/MID LVL ISENTROPIC LIFT IN THE PRESENCE OF
LOW LVL MOISTURE ADVECTION. MID LVL MOISTURE...HOWEVER...WILL BE ON
THE WANE AS LATEST RUC ANALYSIS SHOWS H85-H50 MEAN RH VALUES
DECREASING FROM 60-70PCT OVER CENTRAL/SOUTH FL...TO BLO 50PCT OVER
THE NW CARIB.
THE COMBINATION OF LOW LVL MOISTURE AND MID LVL DRY AIR WILL SET THE
STAGE FOR TSTM DEVELOPMENT THRU MON...ESPECIALLY AS THE STORM SYSTEM
DVLPS AND TRIES TO CRANK A NEW COLD FRONT THROUGH THE DEEP SOUTH.
HOWEVER...PROGRESS OF THE FRONT WILL BE SLOW AS THE ATLC RIDGE
BLOCKS ITS ADVANCE WHILE THE THE STORM SYSTEM LIFTS INTO CANADA AND
ABANDONS THE SRN EXTENT OF ITS TROF. A BRISK S/SW BREEZE WILL
PREVAIL THRU THE H100-H70...ADDING WARM AIR ADVECTION TO THE
PICTURE. ONE MAJOR FACTOR THAT WILL WORK AGAINST A STRONG/SVR WX
EVENT WILL BE THE THERMAL PROFILE. THE -10C H50 ISOTHERM IS
CURRENTLY LOCATED N OF THE I-4 CORRIDOR AND WILL ONLY LIFT FURTHER
NORTH IN THE FACE OF THE MID LVL SWRLY FLOW. H70-H50 LAPSE RATES
OVER THE CENTRAL GOMEX ARE RUNNING A RESPECTABLE 6.5-7.0C/KM...BUT A
PALTRY AOB 5C/KM THRU THE H85-H70 LYR.
WILL OPT FOR CHC/LIKELY SHRAS AND A SLGT CHC OF TSTMS ON SUN...
HIGHEST OVER THE NRN CWA DUE TO A DEEPER MOISTURE PROFILE. POPS
DECREASING TO CHC/SLGT CHC SUN NIGHT AS DRIER AIR AND THE LOSS OF
DIURNAL HEATING SHOULD CHOKE OFF MOST OF ANY STORM ACTIVITY. AS THE
FRONT STALLS OVER THE FL BIG BEND/ERN PANHANDLE...THE DEEPEST
MOISTURE WILL POOL TO THE N...WHILE MID/UPR LVL DEBRIS CLOUDS
DISTURB SFC HEATING/LOW LVL DESTABILIZATION. POPS WILL RANGE FROM
40PCT FROM SRN LAKE/ORANGE/NRN BREVARD NWD...TO 20PCT N/E FROM LAKE
OKEECHOBEE. SRLY FLOW WILL PUSH TEMPS WELL ABV AVG...MAXES INTO THE
L/M80S AND MIN IN THE M/U60S.
TUE-FRI...
UPDATE TO FOLLOW.
&&
.AVIATION...
VFR WITH CIGS OVC-BKN040-060 MLB-SUA AND OVC080-110 KTIX-KMCO NWD.
CIGS WILL LOWER/THICKEN WITH MVFR CONDS DEVELOPING/SPREADING NWD
FROM SUA-FPR. EVENTUALLY EXPECT TO SEE SOME IFR TO LOW END MVFR CIGS
BKN-OVC007-015 BECOME PREVALENT STARTING IN THE 22Z-02Z TIME FRAME.
&&
.MARINE...
TODAY/TONIGHT...THE STRONG HIGH TO THE NORTH WILL MAINTAIN THE TIGHT
LOCAL PGRAD WITH WINDS 20-25KT AND SEAS ALREADY A SOLID 7-9FT ACROSS
THE ENTIRETY OF THE MAOR. WNAWAVE GUIDANCE IS UNDERDOING CURRENT
CONDITIONS BY A GOOD 1-2FT...AND THE NWPS LOOKS MUCH CLOSER TO
REALITY. SEAS UP TO 8FT NEAR SHORE AND 10FT OFFSHORE. HEIGHT OF THE
BREAKERS IN THE SURF ZONE LOOK TO BE A LITTLE SHORT OF HIGH SURF ADV
CRITERIA...NEVERTHELESS LARGE BREAKING WAVES/HIGH SEAS WILL PRODUCE
VERY HAZARDOUS CONDITIONS FOR SMALL CRAFT...AND DANGEROUS SWIMMING/
SURF FOR BEACH GOERS...WITH NUMEROUS STRONG RIPS AND POSSIBLE MINOR
EROSION AROUND THE TIME OF HIGH TIMES.
SUN-MON...UNFAVORABLE CONDITION TO START THE WEEK AS A MODERATE TO
FRESH S/SE BREEZE CONTINUES THRU THE DAY ON SUN...SEAS 5-7FT
NEARSHORE AND 8-10FT OFFSHORE. SFC/BNDRY LYR WINDS BCMG GENTLE TO
MODERATE S/SW ON MON AS A COLD FRONT STALLS OVER THE FL PANHANDLE...
SEAS SUBSIDING TO 3-4FT NEARSHORE AND 5-7FT OFFSHORE.
TUE-WED...UPDATE TO FOLLOW.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 73 69 81 68 / 50 60 60 40
MCO 76 67 83 68 / 50 60 60 40
MLB 76 73 82 70 / 50 50 50 30
VRB 77 74 82 70 / 50 50 50 30
LEE 75 66 83 68 / 50 60 60 40
SFB 75 67 83 67 / 50 60 60 40
ORL 76 68 83 68 / 50 60 60 40
FPR 78 74 82 70 / 50 50 40 30
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 4 PM EST SUNDAY FOR COASTAL WATERS
FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE OUT 20 NM-
COASTAL WATERS FROM SEBASTIAN INLET TO JUPITER INLET OUT 20
NM-COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO
SEBASTIAN INLET OUT 20 NM-WATERS FROM FLAGLER BEACH TO
VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS
FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE-
WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET
20 TO 60 NM OFFSHORE.
&&
$$
SHORT TERM/AVIATION...CRISTALDI
LONG TERM/IMPACT WX...BRAGAW
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
252 AM CST SAT NOV 22 2014
.UPDATE...
746 PM CST
MINOR CHANGES TO THE GOING FORECAST THIS EVENING...MAINLY SLOWING
TIMING OF PRECIP INTO THE REGION. DEWPOINTS REMAIN PRETTY DRY
ACROSS THE REGION WITH SINGLE DIGITS STILL IN PLACE NORTH OF I-80
AND LOW/MID TEENS TO THE SOUTH. REGIONAL RADAR MOSAIC SHOWS
SCATTERED SHOWERS MOVING ACROSS NE MO/SE IA INTO WEST CENTRAL IL
THIS EVENING AND SHOULD START TO OVERSPREAD OUR SOUTHWESTERN
COUNTIES BY AROUND 04Z OR SO...AND INTO THE CHICAGO AREA CLOSER TO
THE 06-07Z HOUR. LOWERED POPS A LITTLE MAINLY DUE TO LIMITED
COVERAGE NOTED UPSTREAM. WHILE TEMPERATURES HAVE SOME DOWNWARD
POTENTIAL FROM WET BULBING THIS EVENING...CLOUDS HAVE STARTED TO
MOVE OVERHEAD WITH A FEW SITES SHOWING TEMPS REBOUNDING A DEGREE
OR TWO...WITH MID/UPPER 30S NOT TOO FAR AWAY. LATEST RAP GUIDANCE
ACTUALLY HAS AIR TEMPERATURES RISING ABOVE FREEZING AROUND THE
ONSET OF PRECIP...SO IT APPEARS THE WINDOW OF POTENTIAL FREEZING
RAIN WILL REMAIN FAIRLY SHORT. WILL MAINTAIN CURRENT ADVISORY
TIMING AS EVEN A LIGHT GLAZE OF ICE CAN BE HAZARDOUS...BUT IF
ANYTHING WE MAY BE ABLE TO LET IT GO A LITTLE EARLY.
BMD
&&
.SHORT TERM...
352 PM CST
THROUGH TONIGHT...
CONDITIONS WILL REMAIN QUIET FOR THE REMAINDER OF THE AFTERNOON
UNDER MOSTLY CLEAR SKIES. LATEST SATELLITE IMAGERY SHOWS A DENSE
MASS OF CLOUD COVER ASSOCIATED WITH A SURGE OF MOISTURE CROSSING THE
MISSOURI VALLEY AND APPROACHING WRN IL. AT THE SURFACE...LATEST OBS
INDICATE DEWPOINTS RAPIDLY INCREASING INTO THE 40S AND 50S WITH THE
MOISTURE SURGE...WHILE DEWPOINTS OVER NRN IL/NWRN IN UNDER THE
MOSTLY CLEAR SKIES REMAIN IN THE SINGLE DIGITS TO THE LOWER TEENS.
THE PCPN SHIELD ASSOCIATED WITH THE APPROACHING SYSTEM WILL TAKE A
LITTLE TIME TO OVERCOME THE VERY DRY AIR IN PLACE...BUT UPSTREAM
TRENDS AND THE SHORT TERM MODEL GUIDANCE ALIGN WELL WITH THE TREND
TO BRING INCREASING POPS INTO THE FAR SWRN PORTIONS OF THE CWA AFTER
SUNSET AND THEN QUICKLY SPREADING TO THE NORTH AND EAST THROUGH THE
EVENING AND OVERNIGHT. THERE WILL BE A SLOW INCREASE IN SFC TEMPS
THROUGH THE NIGHT UNDER STRONG WARM ADVECTION DRIVEN BY A SWLY LOW
LEVEL JET TO 45KT. AVAILABLE DEEP LAYER MOISTURE WITH SYSTEM IS
LIMITED...SO ACTUAL QPF AMOUNTS EXPECTED SHOULD BE RELATIVELY
LIGHT. WILL MAINTAIN AND MAKE NO CHANGES TO THE GOING FREEZING RAIN
ADVISORY. WITH LIGHT QPF AMOUNTS EXPECTED...ANY ICE ACCUMULATION
SHOULD RANGE FROM A LIGHT GLAZING TO A LITTLE OVER A TENTH OF AN
INCH. THERE IS ALSO A CHANCE FOR SOME GLAZING AS EARLY AS 23Z-00Z
OVER THE PONTIAC AREA...WITH SOME LIGHT DRIZZLE OR LIGHT RAIN COMING
IN CONTACT WITH ROAD SURFACES AND WALKWAYS THAT ARE CURRENTLY BELOW
FREEZING DUE TO THE RECENT UNSEASONABLY COLD WEATHER. THROUGH THE
LATE EVENING AND INTO THE OVERNIGHT HOURS...THE FREEZING PCPN WILL
GRADUALLY CHANGE OVER TO A MIX OF FREEZING OR LIQUID TO ALL LIQUID
PCPN AS THE WARMER AIR SURGES INTO THE REGION LATE THIS EVENING AND
OVERNIGHT TONIGHT. THE FREEZING PCPN POTENTIAL SHOULD DIMINISH FROM
SOUTHWEST TO NORTHEAST AS THE WARMER AIR OVERSPREAD THE
REGION...WITH THE FREEZING PCPN POTENTIAL ENDING OVER THE FAR NERN
PORTIONS OF THE CWA...INCLUDING THE FAR NORTHERN PORTIONS OF THE
CHICAGO AREA BY DAYBREAK SATURDAY MORNING.
KREIN
&&
.LONG TERM...
352 PM CST
SATURDAY THROUGH FRIDAY...
FOR THE REMAINDER OF THE DAY ON SATURDAY...WITH LOW PRESSURE
DEEPENING OVER THE NRN PLAINS WHILE HIGH PRESSURE MOVES OFF THE
SOUTH EAST ATLANTIC COAST...THE PERSISTENT FETCH OF WARM...MOIST AIR
WILL CONTINUE TO STREAM OVER THE AREA...WITH LIGHT RAIN PERSISTING
THROUGH THE DAY. TEMPERATURES WILL CONTINUE TO INCREASE THROUGH THE
DAY ON SATURDAY WITH HIGHS RANGING FROM AROUND 50F OVER THE PONTIAC
AREA TO THE MIDDLE 40S OVER THE REMAINDER OF THE CWA. DEWPOINTS ARE
ALSO EXPECTED TO CONTINUE TO RISE THROUGH SATURDAY...REACHING INTO
THE MIDDLE 40S...WHICH WILL BE A STARK CONTRAST TO THE UNSEASONABLY
COLD...DRY AIR THAT HAS BEEN THE PREVAILING CONDITION FOR THE PAST
SEVERAL DAYS. WITH THE MAIN FOCUSING MECHANISM TO MAINTAIN THE PCPN
BEING WIDESPREAD...BUT GRADUAL...ISENTROPIC LIFT...RAINFALL AMOUNTS
WILL CONTINUE TO BE RELATIVELY LIGHT THROUGH SATURDAY NIGHT...WITH
WIDESPREAD AMOUNTS OF A COUPLE TENTHS OF AN INCH.
MORE SIGNIFICANT RAINFALL IS SETTING UP FOR SUNDAY AND INTO SUNDAY
NIGHT AS A STRONG SRN STREAM SHORTWAVE LIFTS OUT OF THE SOUTH HIGH
PLAINS PHASES WITH ANOTHER SHORTWAVE LIFTING FROM THE SOUTHWEST GULF
COAST REGION. THESE SYSTEM WILL RESULT IN A DEEPENING SFC LOW OVER
SRN IL BY SUNDAY EVENING AS A NRN STREAM SHORTWAVE TRACKS ACROSS THE
NRN PLAINS TO THE WRN GREAT LAKE REGION. THE SRN STREAM SYSTEM WILL
BE THE PRIMARY FOCUS FOR HEAVIER RAIN. THE MODELS CONTINUE TO
INDICATE ALMOST UNPRECEDENTED LEVELS OF DEEP LAYER MOISTURE FOR LATE
NOVEMBER...WITH PWATS INCREASING TO IN EXCESS OF 1 INCH THROUGH THE
DAY ON SUNDAY. WHILE ANY THUNDER REMAINS UNLIKELY DUE TO A LACK OF
INSOLATION UNDER PERSISTENT CLOUD COVER...THE UNUSUALLY HIGH
MOISTURE CONTENT SHOULD BRING AREAS OF FOG THROUGH SUNDAY AS WELL AS
SOME LOCALLY HEAVY RAINFALL. WIDESPREAD RAINFALL OF 1 TO 1.5 INCHES
IS POSSIBLE FOR SUNDAY THROUGH SUNDAY NIGHT WITH LOCALIZED AREAS OF
EVEN HEAVIER RAIN POSSIBLE IS SOME CONVECTIVE ELEMENTS CAN DEVELOP.
CONDITIONS WILL REMAIN MUCH WARMER/MOISTER THAN RECENT DAYS THROUGH
SUNDAY WITH HIGHS ONCE AGAIN EXPECTED TO BE IN THE UPPER 40S TO
AROUND 50F.
THE MODELS HAVE SETTLED INTO A RELATIVELY CONSISTENT SOLUTION OF
PHASING THE NRN AND SRN STREAM SHORTWAVES OVER THE ERN GREAT LAKES
BY MONDAY MORNING WITH A SFC LOW ARND 980MB DEVELOPING. AS THE LOW
DEEPENS FURTHER ON MONDAY...STRONG WEST WINDS WILL DEVELOP OVER THE
AREA WITH WINDS INCREASING TO ARND 25 MPH WITH 35MPH GUSTS.
CONSIDERING A POSSIBILITY THAT THE MODELS COULD EVEN BE UNDER
FORECASTING THE POTENTIAL DEEPENING OF THIS LOW...WHICH IS A
POSSIBILITY GIVEN THE LATE FALL CONTRAST OF WARM...MOIST GULF AIR
ASSOCIATED WITH THE SRN STREAM SYSTEM AND MUCH COLDER AIR WITH THE
NRN STREAM SYSTEM...THERE IS THE CHANCE THAT WIND ADVISORY CRITERIA
WINDS OF SUSTAINED 30 MPH WINDS WITH 45 MPH GUSTS MAY OCCUR ON
MONDAY.
THE DEEP SFC LOW IS EXPECTED TO LIFT OUT TO THE NORTHEAST MONDAY
NIGHT AND TUESDAY...WEAK HIGH PRESSURE WILL BUILD ACROSS THE PLAINS
AS THE SFC WHILE BROAD UPPER TROUGHING DEVELOPS OVER THE CNTRL
CONUS. THE UPPER LEVEL PATTERN IS EXPECTED TO BECOME MORE
AMPLIFIED...BUT SLOWLY PROGRESSIVE BY MIDWEEK THROUGH THE END OF NEXT
WEEK...THE AREA REMAINING UNDER PERSISTENT NWLY FLOW AND COLD
ADVECTION ALOFT. SO THE WEEKEND WARMUP SHOULD COME TO AN ABRUPT END
BY MONDAY AS A STRONG COLD FRONT PASSES THROUGH THE REGION AND
TEMPERATURES DROP BACK INTO THE UPPER 30S TO ARND 40F ON MONDAY WITH
HIGHS ONLY IN THE UPPER 20S TO LOWER 30S FOR TUESDAY. THROUGH THE
REMAINDER OF NEXT WEEK...THE TEMPERATURE TREND WILL GO BACK TO WELL
BELOW NORMAL...WITH HIGHS ON THANKSGIVING ONLY IN THE LOWER TO
MIDDLE 20S. A WEAK CLIPPER-TYPE SYSTEM DROPPING OUT OF THE NRN
ROCKIES ON TUESDAY IS EXPECTED TO DIVE INTO THE LOWER MISSISSIPPI
VALLEY BY WEDNESDAY AS ANOTHER WEAK SHORTWAVE DROPS THROUGH THE
UPPER GREAT LAKES. THIS COULD BRING SOME LIGHT SNOW FOR
WEDNESDAY...BUT THEN STRONG HIGH PRESSURE SHOULD BUILD ACROSS THE
MIDDLE MISSISSIPPI VALLEY THROUGH THE GREAT LAKES. THIS COULD SET
UP A WEAK PRESSURE GRADIENT PATTERN OVER THE REGION...BRINGING THE
POSSIBILITY FOR A LAKE EFFECT PLUME TO DEVELOP OVER LAKE MICHIGAN.
WHILE IT IS STILL WAY TOO EARLY TO CONSIDER THE FINER DETAILS OF
LAKE EFFECT SNOW ASSOCIATED WITH MESOSCALE BANDING OF A LAKE
PLUME...THE PATTERN WOULD BE CONDUCIVE FOR SUCH TYPE OF DEVELOPMENT.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* A SMALL CHANCE OF TEMPORARY LIGHT FZRA POSSIBLE PRIOR TO
11Z...THOUGH BASED ON PAVEMENT TEMPERATURES THIS SEEMS MORE
UNLIKELY.
* CIGS LOWERING TO IFR BY DAYBREAK AND THEN POTENTIALLY PERSISTING
AT THAT LEVEL THROUGH THE REMAINDER OF THE TAF.
* IFR VISIBILITY IN DRIZZLE THIS MORNING WITH INTERMITTENT
SHOWERS...ESPECIALLY THE MORNING AND EARLY AFTERNOON.
//DISCUSSION...UPDATED 06Z...
SCATTERED SHOWERS WILL MOVE NORTHEAST OVER THE REGION THROUGH 10Z-
12Z. COVERAGE OF THESE WILL LIKELY INCREASE SOME BUT OVERALL
REMAIN SCATTERED AND GIVEN THE FORCING...WILL ALSO REMAIN MAINLY
LIGHT IN INTENSITY. SOUTHERLY WINDS ARE CONTINUING TO STEER IN
GRADUALLY WARMING TEMPERATURES AS WE PASS THE MIDNIGHT HOUR. IT IS
LIKELY MOST OF THE AIRFIELDS AIR TEMPERATURES WILL REMAIN ABOVE
FREEZING AS SHOWER INTENSITY SHOULD NOT BE ENOUGH TO BRING
TEMPERATURES DOWN TO WET BULB VALUES. HOWEVER...PAVEMENT
TEMPERATURES ARE SLIGHTLY SLOWER TO RESPOND. THIS MAY LEAD TO
LIGHT FREEZING ON SURFACES BEFORE THEY WARM TO OVER 32. BY
DAYBREAK...THE SHOWER ACTIVITY SHOULD HAVE FURTHER DIMINISHED IN
COVERAGE WITH THE PASSAGE OF AN UPPER LEVEL DISTURBANCE...HOWEVER
MOISTENING LOW-LEVELS SHOULD PROVIDE AREAS OF DRIZZLE. IN
TANDEM...CIGS WILL BE FURTHER LOWERING INTO THE IFR CATEGORY AND
VISIBILITY MAY FOLLOW. IFR CIGS MAY PERSIST THROUGH ALL OF SATURDAY
AND EVEN IF THEY DO NOT THEY ARE LIKELY TO RETURN SATURDAY NIGHT.
RAIN SHOULD BE SPREADING NORTHWARD OVER THE AREA DURING OVERNIGHT
SATURDAY NIGHT.
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* HIGH IN SHOWERS...AT TIMES MODERATE IN INTENSITY...THROUGH 11Z
WITH INTERMITTENT SHOWERS IN DRIZZLE AFTER. CONFIDENCE IS HIGH
THAT FREEZING RAIN THREAT HAS DIMINISHED BASED ON WARMED
PAVEMENT TEMPERATURES.
* HIGH IN IFR CIGS THIS MORNING AND THAT THEY WILL FALL TO AT
LEAST 700 FT. LOW ON JUST HOW FAR THEY WILL DROP AND HOW LONG
THEY WILL PERSIST...WITH THE POTENTIAL IT COULD BE THE ENTIRE
TAF DURATION.
* MEDIUM IN DRIZZLE OCCURRING TODAY BUT LOW IN HOW FAR VISIBILITY
WILL DROP WITH IFR POSSIBLE.
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY...RAIN. HEAVY AT TIMES. IFR LIKELY. GUSTY S TO SE WINDS.
MONDAY...CHANCE -RASN EARLY AND -SN LATER. MVFR CIGS POSSIBLE.
GUSTY W TO SW WINDS.
TUESDAY...CHANCE OF FLURRIES. MVFR CIGS PSBL. BREEZY WEST WINDS.
WEDNESDAY...LIGHT SNOW POSSIBLE. MVFR CIGS/VIS POSSIBLE. WEST TO
SOUTHWEST WINDS 10 KT OR LESS.
THANKSGIVING DAY...VFR LIKELY.
MTF
&&
.MARINE...
242 PM...HIGH PRESSURE OVER THE SOUTHERN LAKES AND OHIO VALLEY
WILL MOVE SOUTHEAST TONIGHT REACHING THE CAROLINA COAST ON
SATURDAY AS LOW PRESSURE MOVES ACROSS NORTHERN ONTARIO AND JAMES
BAY TONIGHT. THE GRADIENT BETWEEN THESE TWO SYSTEMS WILL STEADILY
INCREASE OVER LAKE MICHIGAN TONIGHT WITH GALE FORCE WINDS
EXPECTED...POSSIBLY GUSTING AS HIGH AS 45KTS ACROSS THE NORTHERN
PORTION OF THE LAKE. THE GRADIENT WILL BEGIN TO WEAKEN LATER
SATURDAY AFTERNOON INTO SATURDAY EVENING...BUT ANOTHER LOW MOVING
ACROSS THE NORTHERN PLAINS SATURDAY NIGHT INTO SUNDAY WILL TIGHTEN
THE SOUTHERLY GRADIENT AGAIN. THIS LOW WILL BEGIN TO WEAKEN SUNDAY
EVENING AND THEN BE ABSORBED BY ANOTHER STRONGER LOW WHICH WILL
DEVELOP OVER THE SOUTHERN PLAINS SATURDAY NIGHT INTO SUNDAY...THEN
MOVE NORTH ACROSS LAKE MICHIGAN SUNDAY NIGHT INTO MONDAY MORNING.
THIS LOW HAS BEEN FORECAST TO DEEPEN TO AS LOW AS 975MB NEAR LAKE
SUPERIOR FOR SEVERAL DAYS. IF THIS OCCURS...WESTERLY HIGH END
GALES TO 45 KTS WOULD LIKELY DEVELOP MONDAY WITH THE POTENTIAL FOR
SOME STORM FORCE WINDS OR GUSTS. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FREEZING RAIN ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-
ILZ010-ILZ011-ILZ012 UNTIL 9 AM SATURDAY.
FREEZING RAIN ADVISORY...ILZ019-ILZ020 UNTIL 6 AM SATURDAY.
IN...FREEZING RAIN ADVISORY...INZ002-INZ011 UNTIL 6 AM SATURDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM SATURDAY.
SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 3 PM SATURDAY.
&&
$$
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WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1143 PM CST FRI NOV 21 2014
.UPDATE...
746 PM CST
MINOR CHANGES TO THE GOING FORECAST THIS EVENING...MAINLY SLOWING
TIMING OF PRECIP INTO THE REGION. DEWPOINTS REMAIN PRETTY DRY
ACROSS THE REGION WITH SINGLE DIGITS STILL IN PLACE NORTH OF I-80
AND LOW/MID TEENS TO THE SOUTH. REGIONAL RADAR MOSAIC SHOWS
SCATTERED SHOWERS MOVING ACROSS NE MO/SE IA INTO WEST CENTRAL IL
THIS EVENING AND SHOULD START TO OVERSPREAD OUR SOUTHWESTERN
COUNTIES BY AROUND 04Z OR SO...AND INTO THE CHICAGO AREA CLOSER TO
THE 06-07Z HOUR. LOWERED POPS A LITTLE MAINLY DUE TO LIMITED
COVERAGE NOTED UPSTREAM. WHILE TEMPERATURES HAVE SOME DOWNWARD
POTENTIAL FROM WET BULBING THIS EVENING...CLOUDS HAVE STARTED TO
MOVE OVERHEAD WITH A FEW SITES SHOWING TEMPS REBOUNDING A DEGREE
OR TWO...WITH MID/UPPER 30S NOT TOO FAR AWAY. LATEST RAP GUIDANCE
ACTUALLY HAS AIR TEMPERATURES RISING ABOVE FREEZING AROUND THE
ONSET OF PRECIP...SO IT APPEARS THE WINDOW OF POTENTIAL FREEZING
RAIN WILL REMAIN FAIRLY SHORT. WILL MAINTAIN CURRENT ADVISORY
TIMING AS EVEN A LIGHT GLAZE OF ICE CAN BE HAZARDOUS...BUT IF
ANYTHING WE MAY BE ABLE TO LET IT GO A LITTLE EARLY.
BMD
&&
.SHORT TERM...
352 PM CST
THROUGH TONIGHT...
CONDITIONS WILL REMAIN QUIET FOR THE REMAINDER OF THE AFTERNOON
UNDER MOSTLY CLEAR SKIES. LATEST SATELLITE IMAGERY SHOWS A DENSE
MASS OF CLOUD COVER ASSOCIATED WITH A SURGE OF MOISTURE CROSSING THE
MISSOURI VALLEY AND APPROACHING WRN IL. AT THE SURFACE...LATEST OBS
INDICATE DEWPOINTS RAPIDLY INCREASING INTO THE 40S AND 50S WITH THE
MOISTURE SURGE...WHILE DEWPOINTS OVER NRN IL/NWRN IN UNDER THE
MOSTLY CLEAR SKIES REMAIN IN THE SINGLE DIGITS TO THE LOWER TEENS.
THE PCPN SHIELD ASSOCIATED WITH THE APPROACHING SYSTEM WILL TAKE A
LITTLE TIME TO OVERCOME THE VERY DRY AIR IN PLACE...BUT UPSTREAM
TRENDS AND THE SHORT TERM MODEL GUIDANCE ALIGN WELL WITH THE TREND
TO BRING INCREASING POPS INTO THE FAR SWRN PORTIONS OF THE CWA AFTER
SUNSET AND THEN QUICKLY SPREADING TO THE NORTH AND EAST THROUGH THE
EVENING AND OVERNIGHT. THERE WILL BE A SLOW INCREASE IN SFC TEMPS
THROUGH THE NIGHT UNDER STRONG WARM ADVECTION DRIVEN BY A SWLY LOW
LEVEL JET TO 45KT. AVAILABLE DEEP LAYER MOISTURE WITH SYSTEM IS
LIMITED...SO ACTUAL QPF AMOUNTS EXPECTED SHOULD BE RELATIVELY
LIGHT. WILL MAINTAIN AND MAKE NO CHANGES TO THE GOING FREEZING RAIN
ADVISORY. WITH LIGHT QPF AMOUNTS EXPECTED...ANY ICE ACCUMULATION
SHOULD RANGE FROM A LIGHT GLAZING TO A LITTLE OVER A TENTH OF AN
INCH. THERE IS ALSO A CHANCE FOR SOME GLAZING AS EARLY AS 23Z-00Z
OVER THE PONTIAC AREA...WITH SOME LIGHT DRIZZLE OR LIGHT RAIN COMING
IN CONTACT WITH ROAD SURFACES AND WALKWAYS THAT ARE CURRENTLY BELOW
FREEZING DUE TO THE RECENT UNSEASONABLY COLD WEATHER. THROUGH THE
LATE EVENING AND INTO THE OVERNIGHT HOURS...THE FREEZING PCPN WILL
GRADUALLY CHANGE OVER TO A MIX OF FREEZING OR LIQUID TO ALL LIQUID
PCPN AS THE WARMER AIR SURGES INTO THE REGION LATE THIS EVENING AND
OVERNIGHT TONIGHT. THE FREEZING PCPN POTENTIAL SHOULD DIMINISH FROM
SOUTHWEST TO NORTHEAST AS THE WARMER AIR OVERSPREAD THE
REGION...WITH THE FREEZING PCPN POTENTIAL ENDING OVER THE FAR NERN
PORTIONS OF THE CWA...INCLUDING THE FAR NORTHERN PORTIONS OF THE
CHICAGO AREA BY DAYBREAK SATURDAY MORNING.
KREIN
&&
.LONG TERM...
352 PM CST
SATURDAY THROUGH FRIDAY...
FOR THE REMAINDER OF THE DAY ON SATURDAY...WITH LOW PRESSURE
DEEPENING OVER THE NRN PLAINS WHILE HIGH PRESSURE MOVES OFF THE
SOUTH EAST ATLANTIC COAST...THE PERSISTENT FETCH OF WARM...MOIST AIR
WILL CONTINUE TO STREAM OVER THE AREA...WITH LIGHT RAIN PERSISTING
THROUGH THE DAY. TEMPERATURES WILL CONTINUE TO INCREASE THROUGH THE
DAY ON SATURDAY WITH HIGHS RANGING FROM AROUND 50F OVER THE PONTIAC
AREA TO THE MIDDLE 40S OVER THE REMAINDER OF THE CWA. DEWPOINTS ARE
ALSO EXPECTED TO CONTINUE TO RISE THROUGH SATURDAY...REACHING INTO
THE MIDDLE 40S...WHICH WILL BE A STARK CONTRAST TO THE UNSEASONABLY
COLD...DRY AIR THAT HAS BEEN THE PREVAILING CONDITION FOR THE PAST
SEVERAL DAYS. WITH THE MAIN FOCUSING MECHANISM TO MAINTAIN THE PCPN
BEING WIDESPREAD...BUT GRADUAL...ISENTROPIC LIFT...RAINFALL AMOUNTS
WILL CONTINUE TO BE RELATIVELY LIGHT THROUGH SATURDAY NIGHT...WITH
WIDESPREAD AMOUNTS OF A COUPLE TENTHS OF AN INCH.
MORE SIGNIFICANT RAINFALL IS SETTING UP FOR SUNDAY AND INTO SUNDAY
NIGHT AS A STRONG SRN STREAM SHORTWAVE LIFTS OUT OF THE SOUTH HIGH
PLAINS PHASES WITH ANOTHER SHORTWAVE LIFTING FROM THE SOUTHWEST GULF
COAST REGION. THESE SYSTEM WILL RESULT IN A DEEPENING SFC LOW OVER
SRN IL BY SUNDAY EVENING AS A NRN STREAM SHORTWAVE TRACKS ACROSS THE
NRN PLAINS TO THE WRN GREAT LAKE REGION. THE SRN STREAM SYSTEM WILL
BE THE PRIMARY FOCUS FOR HEAVIER RAIN. THE MODELS CONTINUE TO
INDICATE ALMOST UNPRECEDENTED LEVELS OF DEEP LAYER MOISTURE FOR LATE
NOVEMBER...WITH PWATS INCREASING TO IN EXCESS OF 1 INCH THROUGH THE
DAY ON SUNDAY. WHILE ANY THUNDER REMAINS UNLIKELY DUE TO A LACK OF
INSOLATION UNDER PERSISTENT CLOUD COVER...THE UNUSUALLY HIGH
MOISTURE CONTENT SHOULD BRING AREAS OF FOG THROUGH SUNDAY AS WELL AS
SOME LOCALLY HEAVY RAINFALL. WIDESPREAD RAINFALL OF 1 TO 1.5 INCHES
IS POSSIBLE FOR SUNDAY THROUGH SUNDAY NIGHT WITH LOCALIZED AREAS OF
EVEN HEAVIER RAIN POSSIBLE IS SOME CONVECTIVE ELEMENTS CAN DEVELOP.
CONDITIONS WILL REMAIN MUCH WARMER/MOISTER THAN RECENT DAYS THROUGH
SUNDAY WITH HIGHS ONCE AGAIN EXPECTED TO BE IN THE UPPER 40S TO
AROUND 50F.
THE MODELS HAVE SETTLED INTO A RELATIVELY CONSISTENT SOLUTION OF
PHASING THE NRN AND SRN STREAM SHORTWAVES OVER THE ERN GREAT LAKES
BY MONDAY MORNING WITH A SFC LOW ARND 980MB DEVELOPING. AS THE LOW
DEEPENS FURTHER ON MONDAY...STRONG WEST WINDS WILL DEVELOP OVER THE
AREA WITH WINDS INCREASING TO ARND 25 MPH WITH 35MPH GUSTS.
CONSIDERING A POSSIBILITY THAT THE MODELS COULD EVEN BE UNDER
FORECASTING THE POTENTIAL DEEPENING OF THIS LOW...WHICH IS A
POSSIBILITY GIVEN THE LATE FALL CONTRAST OF WARM...MOIST GULF AIR
ASSOCIATED WITH THE SRN STREAM SYSTEM AND MUCH COLDER AIR WITH THE
NRN STREAM SYSTEM...THERE IS THE CHANCE THAT WIND ADVISORY CRITERIA
WINDS OF SUSTAINED 30 MPH WINDS WITH 45 MPH GUSTS MAY OCCUR ON
MONDAY.
THE DEEP SFC LOW IS EXPECTED TO LIFT OUT TO THE NORTHEAST MONDAY
NIGHT AND TUESDAY...WEAK HIGH PRESSURE WILL BUILD ACROSS THE PLAINS
AS THE SFC WHILE BROAD UPPER TROUGHING DEVELOPS OVER THE CNTRL
CONUS. THE UPPER LEVEL PATTERN IS EXPECTED TO BECOME MORE
AMPLIFIED...BUT SLOWLY PROGRESSIVE BY MIDWEEK THROUGH THE END OF NEXT
WEEK...THE AREA REMAINING UNDER PERSISTENT NWLY FLOW AND COLD
ADVECTION ALOFT. SO THE WEEKEND WARMUP SHOULD COME TO AN ABRUPT END
BY MONDAY AS A STRONG COLD FRONT PASSES THROUGH THE REGION AND
TEMPERATURES DROP BACK INTO THE UPPER 30S TO ARND 40F ON MONDAY WITH
HIGHS ONLY IN THE UPPER 20S TO LOWER 30S FOR TUESDAY. THROUGH THE
REMAINDER OF NEXT WEEK...THE TEMPERATURE TREND WILL GO BACK TO WELL
BELOW NORMAL...WITH HIGHS ON THANKSGIVING ONLY IN THE LOWER TO
MIDDLE 20S. A WEAK CLIPPER-TYPE SYSTEM DROPPING OUT OF THE NRN
ROCKIES ON TUESDAY IS EXPECTED TO DIVE INTO THE LOWER MISSISSIPPI
VALLEY BY WEDNESDAY AS ANOTHER WEAK SHORTWAVE DROPS THROUGH THE
UPPER GREAT LAKES. THIS COULD BRING SOME LIGHT SNOW FOR
WEDNESDAY...BUT THEN STRONG HIGH PRESSURE SHOULD BUILD ACROSS THE
MIDDLE MISSISSIPPI VALLEY THROUGH THE GREAT LAKES. THIS COULD SET
UP A WEAK PRESSURE GRADIENT PATTERN OVER THE REGION...BRINGING THE
POSSIBILITY FOR A LAKE EFFECT PLUME TO DEVELOP OVER LAKE MICHIGAN.
WHILE IT IS STILL WAY TOO EARLY TO CONSIDER THE FINER DETAILS OF
LAKE EFFECT SNOW ASSOCIATED WITH MESOSCALE BANDING OF A LAKE
PLUME...THE PATTERN WOULD BE CONDUCIVE FOR SUCH TYPE OF DEVELOPMENT.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* TEMPORARY LIGHT FZRA POSSIBLE PRIOR TO 09Z-10Z...WITH GRADUALLY
WARMING TEMPERATURES LIKELY YIELDING TEMPORARY -SHRA AFTER THAT
POINT THROUGH DAYBREAK.
* CIGS GRADUALLY LOWERING TO IFR BY DAYBREAK AND POTENTIALLY
PERSISTING THROUGH THE REMAINDER OF THE TAF.
* IFR VISIBILITY IN DRIZZLE POSSIBLE SATURDAY...ESPECIALLY THE
MORNING AND EARLY AFTERNOON.
//DISCUSSION...UPDATED 06Z...
SCATTERED SHOWERS WILL MOVE NORTHEAST OVER THE REGION THROUGH 10Z-
12Z. COVERAGE OF THESE WILL LIKELY INCREASE SOME BUT OVERALL
REMAIN SCATTERED AND GIVEN THE FORCING...WILL ALSO REMAIN MAINLY
LIGHT IN INTENSITY. SOUTHERLY WINDS ARE CONTINUING TO STEER IN
GRADUALLY WARMING TEMPERATURES AS WE PASS THE MIDNIGHT HOUR. IT IS
LIKELY MOST OF THE AIRFIELDS AIR TEMPERATURES WILL REMAIN ABOVE
FREEZING AS SHOWER INTENSITY SHOULD NOT BE ENOUGH TO BRING
TEMPERATURES DOWN TO WET BULB VALUES. HOWEVER...PAVEMENT
TEMPERATURES ARE SLIGHTLY SLOWER TO RESPOND. THIS MAY LEAD TO
LIGHT FREEZING ON SURFACES BEFORE THEY WARM TO OVER 32. BY
DAYBREAK...THE SHOWER ACTIVITY SHOULD HAVE FURTHER DIMINISHED IN
COVERAGE WITH THE PASSAGE OF AN UPPER LEVEL DISTURBANCE...HOWEVER
MOISTENING LOW-LEVELS SHOULD PROVIDE AREAS OF DRIZZLE. IN
TANDEM...CIGS WILL BE FURTHER LOWERING INTO THE IFR CATEGORY AND
VISIBILITY MAY FOLLOW. IFR CIGS MAY PERSIST THROUGH ALL OF SATURDAY
AND EVEN IF THEY DO NOT THEY ARE LIKELY TO RETURN SATURDAY NIGHT.
RAIN SHOULD BE SPREADING NORTHWARD OVER THE AREA DURING OVERNIGHT
SATURDAY NIGHT.
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH IN LIGHT SHOWERS OCCURRING AND TIMING BUT LOW IN WHETHER IT
WILL FREEZE AS AIR TEMPERATURES WILL LIKELY BE ABOVE 32 AND ANY
FREEZING WILL DEPEND HEAVILY ON PAVEMENT TEMPERATURES.
* HIGH IN IFR CIGS SATURDAY MORNING AND MEDIUM IN HOW FAR THEY
WILL DROP.
* MEDIUM IN DRIZZLE OCCURRING SATURDAY BUT LOW IN HOW FAR
VISIBILITY WILL DROP WITH IFR POSSIBLE.
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY...RAIN. HEAVY AT TIMES. IFR LIKELY. GUSTY S TO SE WINDS.
MONDAY...CHANCE -RASN EARLY AND -SN LATER. MVFR CIGS POSSIBLE.
GUSTY W TO SW WINDS.
TUESDAY...CHANCE OF FLURRIES. MVFR CIGS PSBL. BREEZY WEST WINDS.
WEDNESDAY...LIGHT SNOW POSSIBLE. MVFR CIGS/VIS POSSIBLE. WEST TO
SOUTHWEST WINDS 10 KT OR LESS.
THANKSGIVING DAY...VFR LIKELY.
MTF
&&
.MARINE...
242 PM...HIGH PRESSURE OVER THE SOUTHERN LAKES AND OHIO VALLEY
WILL MOVE SOUTHEAST TONIGHT REACHING THE CAROLINA COAST ON
SATURDAY AS LOW PRESSURE MOVES ACROSS NORTHERN ONTARIO AND JAMES
BAY TONIGHT. THE GRADIENT BETWEEN THESE TWO SYSTEMS WILL STEADILY
INCREASE OVER LAKE MICHIGAN TONIGHT WITH GALE FORCE WINDS
EXPECTED...POSSIBLY GUSTING AS HIGH AS 45KTS ACROSS THE NORTHERN
PORTION OF THE LAKE. THE GRADIENT WILL BEGIN TO WEAKEN LATER
SATURDAY AFTERNOON INTO SATURDAY EVENING...BUT ANOTHER LOW MOVING
ACROSS THE NORTHERN PLAINS SATURDAY NIGHT INTO SUNDAY WILL TIGHTEN
THE SOUTHERLY GRADIENT AGAIN. THIS LOW WILL BEGIN TO WEAKEN SUNDAY
EVENING AND THEN BE ABSORBED BY ANOTHER STRONGER LOW WHICH WILL
DEVELOP OVER THE SOUTHERN PLAINS SATURDAY NIGHT INTO SUNDAY...THEN
MOVE NORTH ACROSS LAKE MICHIGAN SUNDAY NIGHT INTO MONDAY MORNING.
THIS LOW HAS BEEN FORECAST TO DEEPEN TO AS LOW AS 975MB NEAR LAKE
SUPERIOR FOR SEVERAL DAYS. IF THIS OCCURS...WESTERLY HIGH END
GALES TO 45 KTS WOULD LIKELY DEVELOP MONDAY WITH THE POTENTIAL FOR
SOME STORM FORCE WINDS OR GUSTS. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FREEZING RAIN ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-
ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ020-ILZ022 UNTIL 9 AM
SATURDAY.
FREEZING RAIN ADVISORY...ILZ019-ILZ021-ILZ023-ILZ032-ILZ033-
ILZ039 UNTIL 6 AM SATURDAY.
IN...FREEZING RAIN ADVISORY...INZ001-INZ002 UNTIL 9 AM SATURDAY.
FREEZING RAIN ADVISORY...INZ010-INZ011-INZ019 UNTIL 6 AM
SATURDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM SATURDAY.
SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 3 PM SATURDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1205 AM EST SAT NOV 22 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 332 PM EST FRI NOV 21 2014
HIGH PRESSURE WILL PUSH OFF TO THE EAST AS A WARM FRONT AND A STRONG
LOW PRESSURE SYSTEM ENTER FROM THE SOUTHWEST TONIGHT. THIS SYSTEM
WILL KEEP PRECIPITATION IN THE FORECAST THROUGH THE WEEKEND. IN ITS
WAKE...COLDER AND DRIER WEATHER WILL RETURN...THEN A UPPER LEVEL
SYSTEM WILL BRING CHANCES FOR SNOW TO THE AREA NEXT WEDNESDAY
THROUGH THURSDAY.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 953 PM EST FRI NOV 21 2014
PRECIP CONTINUES TO BE SLOW TO MOVE INTO THE AREA AND IS SPOTTY AT
BEST FOR THE MOMENT. HRRR DOES INDICATE AN EXPANSION IN COVERAGE
OVER THE NEXT SEVERAL HOURS BUT CONCURRENTLY BRINGS TEMPERATURES UP
AS IT MOVES THE PRECIP IN. HAVE ADJUSTED MIN TEMPS AND HOURLY TEMPS
AS THE WARM ADVECTION CONTINUES...MANY SITES IN THE SOUTHWEST HAVE
LIKELY ALREADY HIT THEIR MINS FOR THE NIGHT.
WILL CONTINUE TO CARRY FREEZING RAIN IN THE GRIDS WHERE THE HOURLY
TEMPS ARE AT OR BELOW 32 WITH A SMALL MARGIN OF RAIN OR FREEZING
RAIN OWING TO UNCERTAINTY...BUT THIS WILL RESULT IN A VERY SHORT
WINDOW OF ICING THREAT AT ANY ONE LOCATION...LIKELY 2-3 HOURS AT
MOST...MAYBE 4 HOURS IN THE NORTH OR NORTHEAST WHICH HAS A BIT
FURTHER TO GO TO THE FREEZING MARK.
PREVIOUS DISCUSSIONS FOLLOW.
ISSUED AT 657 PM EST FRI NOV 21 2014
WITH REGIONAL RADAR TRENDS VERY SLOW TO SHOW ANY ECHOES AT
ALL AND DEWPOINTS REMAINING VERY DRY ACROSS THE AREA...HAVE PUSHED
BACK POPS AT LEAST A FEW HOURS WITH THIS UPDATE...AND MAY NEED TO
PUSH THEM BACK EVEN MORE DEPENDING ON HOW THINGS EVOLVE OVER THE
NEXT FEW HOURS. HRRR DOES HAVE SOME PRECIP IN THE FAR SOUTHWEST BY
04Z. IT IS A RACE BETWEEN WARM ADVECTION AND PRECIP ONSET AT THIS
POINT TO DETERMINE WHETHER ANY FREEZING PRECIP WILL FALL. PREVIOUS
DISCUSSION FOLLOWS.
ISSUED AT 332 PM EST FRI NOV 21 2014
FOR THE REST OF THIS AFTERNOON AND EARLY EVENING EXPECT INCREASING
CLOUD COVER FROM SOUTHWEST TO NORTHEAST AS A FRONTAL SYSTEM DRAPED
MOVES CLOSER TO THE FORECAST AREA. MODELS ARE TIMING THE MOISTURE
FROM THIS SYSTEM TO ARRIVE EVEN SLOWER THAN EXPECTED WHICH WILL
IMPACT PRECIP TYPE OVERNIGHT WHERE ONCE WIDESPREAD FREEZING RAIN WAS
EXPECTED. THIS PERIOD OF LIGHT FREEZING RAIN LOOKS LIKE A MUCH
SMALLER WINDOW FOR CENTRAL INDIANA AS WARM AIR ADVECTION REALLY
KICKS IN LATER THIS EVENING AND SURFACE TEMPERATURES BEGIN TO RISE
TO ABOVE FREEZING. THIS COMBINED WITH THE MUCH SLOWER ONSET OF
PRECIP. THE MAIN WINDOW FOR -FZRA RAIN IS 9PM THROUGH 5AM...QUICKLY
CHANGING OVER TO RAIN FROM SW TO NE AS THE WARMER AIR ARRIVES. QPF
AMOUNTS STILL LOOK EXTREMELY LOW...ONLY A FEW HUNDREDTHS OF AN INCH.
OPTED NOT TO ISSUE ANY STATEMENTS NOR HEADLINES FOR THE -FZRA RAIN
BASED ON THIS LATEST GUIDANCE AND WILL CONTINUE TO MONITOR
CONDITIONS UPSTREAM TO SEE IF A SPECIAL WEATHER STATEMENT IS NEEDED.
IN COORDINATION WITH SURROUNDING OFFICES WILL CONTINUE TO MENTION
THE LIGHT FREEZING RAIN AND POTENTIALLY SLICK/ICY ROADS FOR A BRIEF
PERIOD OVERNIGHT IN THE HWO AND WX STORY.
LOW TEMPS WILL OCCUR EARLY THIS EVENING (RANGING FROM MID 20S TO MID
30S) AND QUICKLY INCREASE TO MID 30S TO LOW 40S BY 12Z SAT!
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
ISSUED AT 332 PM EST FRI NOV 21 2014
BY 10-12Z SATURDAY MORNING ALL THE POTENTIAL -FZRA WILL HAVE CHANGED
OVER TO RAIN. AND WARM AIR ADVECTION WILL CONTINUE TO FILTER INTO
THE AREA IN EARNEST THROUGH SATURDAY WITH HIGH TEMPERATURES COMING
IN EVEN WARMER THIS MODEL RUN WITH HIGHS RANGING FROM MID 40S
(NORTH) TO NEARLY THE MID 50S (FAR SOUTH COUNTIES) BY SAT 12Z
THE SURFACE LOW WILL CONTINUE ITS TRACK ACROSS THE MISSISSIPPI
VALLEY ON SATURDAY INTO SATURDAY NIGHT AND THERE CONTINUES TO LOOKS
LIKE A LULL DURING A GOOD PORTION OF THE DAY SATURDAY...SO BACK OFF
ON POPS OVER THE ENTIRE AREA. THE HIGHEST CHANCES FOR RAIN WILL BE
ON SUNDAY AS BEST LIFT FROM WARM FRONT AND LOW PRESSURE MOVES ACROSS
THE AREA. WILL CONTINUE WITH 100 PERCENT POPS...ESPECIALLY FOR THE
SECOND HALF OF SUNDAY.
IN TERMS OF TEMPS...AS MENTIONED ABOVE EXPECT HIGHS TO CLIMB INTO
THE 50S WITH DECENT WARM ADVECTION...AND LOWS TO BE IN THE 40S.
RAIN WILL SLOWLY BEGIN TO TAPER OFF ON MONDAY AS THE SYSTEM SLOWLY
MOST OFF TO THE EAST. COLD AIR WILL THEN MOVE BACK IN MONDAY
NIGHT IN THE WAKE OF THE FRONTAL PASSAGE. COULD SEE A FEW SNOW
SHOWERS IN THE NORTH AS WEAK WAVE MOVES THROUGH. FOR NOW INDICATED
A MIX OF -RA/SN LATE MONDAY AFTERNOON AND SLIGHT CHANCES FOR SNOW
SHOWERS OR FLURRIES ACROSS THE FAR NORTHERN TIER OF COUNTIES
MONDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 255 PM EST FRI NOV 21 2014
COLD AIR WILL MOVE BACK IN MONDAY NIGHT IN THE WAKE OF THE FRONTAL
PASSAGE. COULD SEE A FEW SNOW SHOWERS IN THE NORTH AS WEAK WAVE
MOVES THROUGH. KEPT CHANCE FOR FLURRIES GOING TUESDAY IN THE
NORTHERN HALF OR SO AS WELL WITH CYCLONIC UPPER FLOW. WEDNESDAY ON
MODELS ARE SHOWING SOME DECENT DIFFERENCES IN THE UPPER PATTERN AND
ENSEMBLES ARE PRETTY VARIABLE SO WILL JUST GO WITH INITIALIZATION.
TEMPERATURES DO SEEM TO BE COMING TOGETHER A LITTLE COOLER FOR THAT
TIME SO STUCK WITH SMALL CHANCES FOR SNOW FOR PRECIP TYPE. THERE IS
SOME HINT OF A WARMUP OUT BEYOND FRIDAY BUT THAT REMAINS TO BE SEEN.
&&
.AVIATION /DISCUSSION FOR THE 22/06Z TAFS/...
ISSUED AT 1205 AM EST SAT NOV 22 2014
VFR EXPECTED INITIALLY. A BRIEF PERIOD OF MVFR WILL BE
POSSIBLE FROM 08Z-12Z...BEFORE VFR CONDITIONS RETURN.
LIGHT FREEZING RAIN WILL BE POSSIBLE OVERNIGHT AT LAF.
ELSEWHERE...TEMPERATURES SHOULD WARM TO NEAR OR ABOVE FREEZING NEAR
PRECIP ONSET...SO ANY FREEZING PRECIP WILL LIKELY BE VERY BRIEF.
TIME HEIGHTS THEN CONTINUE TO SHOW PLENTIFUL LOWER LEVEL MOISTURE
THROUGH THE FORECAST PERIOD AMID WARM AIR ADVECTION WITHIN THE
COLUMN. THUS A RETURN TO VFR WILL BE EXPECTED AFT 12Z WITH SCT
SHOWERS IN THE AREA. A STRONG LLJ OF 50KT WORKING ACROSS THE AREA
MAY RESULT IN SOME LLWS WHICH HAS BEEN INCLUDED.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF/NIELD
SHORT TERM...SMF
LONG TERM...CP
AVIATION...JP/NIELD/JH
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AREA FORECAST DISCUSSION
NWS GOODLAND KS
1050 PM MST FRI NOV 21 2014
.UPDATE...
ISSUED AT 1050 PM MST FRI NOV 21 2014
REPORTS OF DENSE FOG WITH LOW VISIBILITY IN EASTERN ZONES HAS
PROMPTED ISSUANCE OF DENSE FOG ADVISORY FROM NOW INTO SATURDAY
MORNING AROUND 900 AM CST. NO OTHER CHANGES MADE.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 138 PM MST FRI NOV 21 2014
MAIN CONCERNS ARE EXTENT OF FOG TONIGHT FOLLOWED BY HOW MUCH TO
WARM UP THE TEMPERATURES ON SATURDAY. LARGE AREA OF STRATUS AND
SOME FOG TO OUR SOUTH AND SOUTHEAST AT THIS TIME. RETURN FLOW WILL
BE IN PLACE BY THE TIME SUN GOES DOWN AND THE LOW LEVEL INVERSION
STRENGTHENS. SO WOULD EXPECT THIS MOISTURE TO BE ABLE TO RETURN
NORTH AND MOVE INTO THE AREA BEFORE THE WINDS SHIFT TO A WEST TO
SOUTHWEST DIRECTION BY LATER TONIGHT AS A SURFACE TROUGH MOVES
THROUGH.
HRRR FOLLOWED BY RAP HAVE BEEN DOING VERY WELL IN THE DEPICTION OF
THIS LOW LEVEL MOISTURE FIELD. BASED ON THAT AND THE OBSERVATIONS
TO OUR SOUTH...WENT AHEAD AND FOLLOWED THE HRRR/RAP VERY CLOSELY
FOR THE CLOUD COVER AND FOG FOR TONIGHT. FOG/LOW CLOUDS SHOULD
STAY IN THE EASTERN HALF TO TWO THIRDS OF THE AREA. IF HRRR ENDS
UP BEING RIGHT THERE COULD BE SOME DENSE FOG POSSIBLE IN THE FAR
EASTERN PORTION.
FOG AND STRATUS DECREASE LATE TONIGHT AND EARLY TOMORROW AS
SURFACE TROUGH MOVES THROUGH AND SHIFTS/INCREASES THE WINDS FROM
THE WEST. AT THIS TIME THE FOG SHOULD END BY MID MORNING. ONCE THE
FOG/CLOUDS CLEAR OFF THERE WILL BE PLENTIFUL SUNSHINE AND
DOWNSLOPE WINDS THROUGH 700 MB. COMBINATION OF DRY AIR MASS AND
GROUND COMBINED WITH THE ABUNDANT SUNSHINE AND DOWNSLOPE WINDS
WILL ALLOW FOR A GOOD WARMUP.
QUESTION IS HOW MUCH. THE NWP AND ESPECIALLY THE 2 METER GUIDANCE
HAS BEEN RUNNING COOL DURING THE LAST WEEK. AT THIS TIME WENT
ABOVE GUIDANCE IN MOST PLACES WITH 60S...MOSTLY MIDDLE AND UPPER
60S....ACROSS THE ENTIRE AREA.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 210 PM MST FRI NOV 21 2014
FOR THE EXTENDED FORECAST PERIOD...VARIABLE WEATHER CONDITIONS ARE
EXPECTED THROUGHOUT DUE TO PASSING COLD FRONTS UNDER A NORTHWEST
FLOW REGIME. OVERALL...THE PATTERN REMAINS FAIRLY CONSISTENT WITH
LITTLE CHANCE OF MAJOR PRECIPITATION-PRODUCING SYSTEMS REACHING THE
REGION. PRIMARY CHANGE TO THIS EXTENDED PACKAGE WAS TO REMOVE
PRECIPITATION CHANCES FOR THANKSGIVING. MORE DETAILS ON THIS BELOW.
FOR SATURDAY NIGHT INTO SUNDAY MORNING...A STRONG COLD FRONT PASSAGE
IS ANTICIPATED. TEMPERATURES WILL BE SLOW TO FALL SATURDAY NIGHT DUE
TO INCREASING CLOUD COVER. THEN...A QUICK DROP IN TEMPERATURES AND
GUSTY NORTH WINDS ARE LIKELY IMMEDIATELY BEHIND THE FRONT. AS THE
FRONT PASSES THROUGH...THE ATMOSPHERE MOISTENS AT LOW LEVELS WHEN
THE COOLER AIR INTRUDES. THERE SHOULD BE ENOUGH MID-LEVEL LIFT AND
MOISTURE FOR RAIN/SNOW SHOWERS DEVELOPMENT BUT THE QUESTION OVER THE
PAST FEW FORECAST RUNS HAS BEEN WHETHER OR NOT THIS PRECIPITATION
REACHES THE GROUND. BASED ON LATEST GUIDANCE...THERE SHOULD BE A
SMALL WINDOW OF OPPORTUNITY FOR MEASURABLE PRECIPITATION TO REACH
THE GROUND AHEAD OF INCOMING POST-FRONTAL DRY AIR. THEREFORE...
PLACED A SLIGHT CHANCE FOR MEASURABLE PRECIPITATION INTO THE
FORECAST AND MAINTAINED SPRINKLES/FLURRIES MENTION SURROUNDING THE
SLIGHT CHANCE POPS.
MAIN STORY FOR THE REST OF SUNDAY THROUGH MONDAY SHOULD BE
BREEZY/WINDY CONDITIONS AND COOL TEMPERATURES. WITH PERSISTENT COLD
AIR ADVECTION AND POSSIBLE CLOUD COVER OVERHEAD...HAVE A HARD TIME
BELIEVING THAT THE REGION WILL BE ABLE TO REACH MEX/MET/ECE GUIDANCE
TEMPERATURES. WENT BELOW GUIDANCE FOR HIGH TEMPERATURES DUE TO THIS
THINKING. REGARDING THE WINDS...MODELS ARE NOT IN STRONG AGREEMENT
WITH RESPECT TO HOW STRONG THE WINDS WILL BE AND WHEN THE STRONGEST
WINDS WILL OCCUR. ANY POSSIBLE CLOUD COVER ALSO MESSES WITH
ANTICIPATED MIXING HEIGHTS SO HARD TO TELL HOW STRONG THE MIXED DOWN
GUSTS WILL BE AT THIS TIME. WITHOUT A STRONG CUT-OFF LOW PRESSURE
SYSTEM PRESENT...CURRENTLY DO NOT BELIEVE THAT THIS WILL BE A MAJOR
WIND EVENT. TYPICAL COLD/WINDY HIGH PLAINS DAYS ARE FORECAST WITH
NORTH WINDS 20-30 MPH...GUSTING TO 45 MPH AND HIGH TEMPERATURES IN
THE LOW TO UPPER 40S.
BEYOND MONDAY...A WEAK UPPER LEVEL DISTURBANCE MOVES THROUGH THE
HIGH PLAINS TUESDAY INTO TUESDAY NIGHT. THE CR INITIALIZATION
PROCEDURE DID NOT INCLUDE POPS AND WITH A DRY LAYER OF AIR AT THE
SURFACE...THOUGHT THIS WAS APPROPRIATE. POPS MAY NEED TO BE INCLUDED
AT A LATER TIME BUT MODEL CONSISTENCY WAS NOT STRONG ENOUGH FOR
INCLUSION WITH THIS RUN.
ANOTHER STRONG UPPER LEVEL DISTURBANCE SWINGS SOUTH OVER THE PLAINS
AND INTO THE MID-MISSISSIPPI VALLEY BY THURSDAY. THIS SYSTEM SHOULD
FORCE A BACKDOOR COLD FRONT INTO THE HIGH PLAINS. IT IS HARD TO TELL
HOW FAR SOUTHWEST THIS FRONT WILL REACH AND THERE IS A STRONG CHANCE
FOR A LARGE TEMPERATURE GRADIENT ACROSS THE REGION. CURRENT
THANKSGIVING FORECAST CALLS FOR A HIGH OF 38 DEGREES AT MCCOOK
NEBRASKA...44 AT GOODLAND KANSAS AND 52 AT KIT CARSON COLORADO.
MODELS TRENDED PRECIPITATION CHANCES FOR THANKSGIVING DOWN AND
BELIEVE THIS IS ACCURATE CONSIDERING A RIDGE OF HIGH PRESSURE WILL
BUILD IN FROM THE WEST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1024 PM MST FRI NOV 21 2014
FOR KGLD...VFR CONDITIONS WITH MIX OF SKC AND SCT-BKN150 AFT 12Z
SATURDAY. WINDS WSW AROUND 10KTS.
FOR KMCK...MAINLY VFR CONDITIONS WITH MIX OF SKC AND SCT-BKN150
AFT 14Z SATURDAY. MVFR FOG POSSIBLE DOWN TO 4SM AT TIMES FROM
08Z-12Z SATURDAY. WINDS WSW AROUND 10KTS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY UNTIL 9 AM CST SATURDAY FOR KSZ002>004-
014>016-028-029.
CO...NONE.
NE...DENSE FOG ADVISORY UNTIL 9 AM CST SATURDAY FOR NEZ080-081.
&&
$$
UPDATE...JN
SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...JN
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1024 PM MST FRI NOV 21 2014
.UPDATE...
ISSUED AT 926 PM MST FRI NOV 21 2014
UPDATE TO ZONES SENT OUT TO ACCOMMODATE LATEST TEMP TRENDS FROM
AREA OBS. LOW LEVEL CLOUDS COVER STILL LINGERING OVER EASTERN
EDGES OF THE FORECAST AREA AND SHOULD CONTINUE TREK EASTWARD
OVERNIGHT. THIS WILL GIVE WAY TO MID LEVEL CLOUDS WHICH ARE
CURRENTLY CENTRAL/WESTERN AREAS. LATEST EASTERN ZONES OBS ARE
STARTING TO SHOW FOG DEVELOPING...SO HAVE LEFT THAT IN OVERNIGHT.
REST OF FORECAST ON TRACK.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 138 PM MST FRI NOV 21 2014
MAIN CONCERNS ARE EXTENT OF FOG TONIGHT FOLLOWED BY HOW MUCH TO
WARM UP THE TEMPERATURES ON SATURDAY. LARGE AREA OF STRATUS AND
SOME FOG TO OUR SOUTH AND SOUTHEAST AT THIS TIME. RETURN FLOW WILL
BE IN PLACE BY THE TIME SUN GOES DOWN AND THE LOW LEVEL INVERSION
STRENGTHENS. SO WOULD EXPECT THIS MOISTURE TO BE ABLE TO RETURN
NORTH AND MOVE INTO THE AREA BEFORE THE WINDS SHIFT TO A WEST TO
SOUTHWEST DIRECTION BY LATER TONIGHT AS A SURFACE TROUGH MOVES
THROUGH.
HRRR FOLLOWED BY RAP HAVE BEEN DOING VERY WELL IN THE DEPICTION OF
THIS LOW LEVEL MOISTURE FIELD. BASED ON THAT AND THE OBSERVATIONS
TO OUR SOUTH...WENT AHEAD AND FOLLOWED THE HRRR/RAP VERY CLOSELY
FOR THE CLOUD COVER AND FOG FOR TONIGHT. FOG/LOW CLOUDS SHOULD
STAY IN THE EASTERN HALF TO TWO THIRDS OF THE AREA. IF HRRR ENDS
UP BEING RIGHT THERE COULD BE SOME DENSE FOG POSSIBLE IN THE FAR
EASTERN PORTION.
FOG AND STRATUS DECREASE LATE TONIGHT AND EARLY TOMORROW AS
SURFACE TROUGH MOVES THROUGH AND SHIFTS/INCREASES THE WINDS FROM
THE WEST. AT THIS TIME THE FOG SHOULD END BY MID MORNING. ONCE THE
FOG/CLOUDS CLEAR OFF THERE WILL BE PLENTIFUL SUNSHINE AND
DOWNSLOPE WINDS THROUGH 700 MB. COMBINATION OF DRY AIR MASS AND
GROUND COMBINED WITH THE ABUNDANT SUNSHINE AND DOWNSLOPE WINDS
WILL ALLOW FOR A GOOD WARMUP.
QUESTION IS HOW MUCH. THE NWP AND ESPECIALLY THE 2 METER GUIDANCE
HAS BEEN RUNNING COOL DURING THE LAST WEEK. AT THIS TIME WENT
ABOVE GUIDANCE IN MOST PLACES WITH 60S...MOSTLY MIDDLE AND UPPER
60S....ACROSS THE ENTIRE AREA.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 210 PM MST FRI NOV 21 2014
FOR THE EXTENDED FORECAST PERIOD...VARIABLE WEATHER CONDITIONS ARE
EXPECTED THROUGHOUT DUE TO PASSING COLD FRONTS UNDER A NORTHWEST
FLOW REGIME. OVERALL...THE PATTERN REMAINS FAIRLY CONSISTENT WITH
LITTLE CHANCE OF MAJOR PRECIPITATION-PRODUCING SYSTEMS REACHING THE
REGION. PRIMARY CHANGE TO THIS EXTENDED PACKAGE WAS TO REMOVE
PRECIPITATION CHANCES FOR THANKSGIVING. MORE DETAILS ON THIS BELOW.
FOR SATURDAY NIGHT INTO SUNDAY MORNING...A STRONG COLD FRONT PASSAGE
IS ANTICIPATED. TEMPERATURES WILL BE SLOW TO FALL SATURDAY NIGHT DUE
TO INCREASING CLOUD COVER. THEN...A QUICK DROP IN TEMPERATURES AND
GUSTY NORTH WINDS ARE LIKELY IMMEDIATELY BEHIND THE FRONT. AS THE
FRONT PASSES THROUGH...THE ATMOSPHERE MOISTENS AT LOW LEVELS WHEN
THE COOLER AIR INTRUDES. THERE SHOULD BE ENOUGH MID-LEVEL LIFT AND
MOISTURE FOR RAIN/SNOW SHOWERS DEVELOPMENT BUT THE QUESTION OVER THE
PAST FEW FORECAST RUNS HAS BEEN WHETHER OR NOT THIS PRECIPITATION
REACHES THE GROUND. BASED ON LATEST GUIDANCE...THERE SHOULD BE A
SMALL WINDOW OF OPPORTUNITY FOR MEASURABLE PRECIPITATION TO REACH
THE GROUND AHEAD OF INCOMING POST-FRONTAL DRY AIR. THEREFORE...
PLACED A SLIGHT CHANCE FOR MEASURABLE PRECIPITATION INTO THE
FORECAST AND MAINTAINED SPRINKLES/FLURRIES MENTION SURROUNDING THE
SLIGHT CHANCE POPS.
MAIN STORY FOR THE REST OF SUNDAY THROUGH MONDAY SHOULD BE
BREEZY/WINDY CONDITIONS AND COOL TEMPERATURES. WITH PERSISTENT COLD
AIR ADVECTION AND POSSIBLE CLOUD COVER OVERHEAD...HAVE A HARD TIME
BELIEVING THAT THE REGION WILL BE ABLE TO REACH MEX/MET/ECE GUIDANCE
TEMPERATURES. WENT BELOW GUIDANCE FOR HIGH TEMPERATURES DUE TO THIS
THINKING. REGARDING THE WINDS...MODELS ARE NOT IN STRONG AGREEMENT
WITH RESPECT TO HOW STRONG THE WINDS WILL BE AND WHEN THE STRONGEST
WINDS WILL OCCUR. ANY POSSIBLE CLOUD COVER ALSO MESSES WITH
ANTICIPATED MIXING HEIGHTS SO HARD TO TELL HOW STRONG THE MIXED DOWN
GUSTS WILL BE AT THIS TIME. WITHOUT A STRONG CUT-OFF LOW PRESSURE
SYSTEM PRESENT...CURRENTLY DO NOT BELIEVE THAT THIS WILL BE A MAJOR
WIND EVENT. TYPICAL COLD/WINDY HIGH PLAINS DAYS ARE FORECAST WITH
NORTH WINDS 20-30 MPH...GUSTING TO 45 MPH AND HIGH TEMPERATURES IN
THE LOW TO UPPER 40S.
BEYOND MONDAY...A WEAK UPPER LEVEL DISTURBANCE MOVES THROUGH THE
HIGH PLAINS TUESDAY INTO TUESDAY NIGHT. THE CR INITIALIZATION
PROCEDURE DID NOT INCLUDE POPS AND WITH A DRY LAYER OF AIR AT THE
SURFACE...THOUGHT THIS WAS APPROPRIATE. POPS MAY NEED TO BE INCLUDED
AT A LATER TIME BUT MODEL CONSISTENCY WAS NOT STRONG ENOUGH FOR
INCLUSION WITH THIS RUN.
ANOTHER STRONG UPPER LEVEL DISTURBANCE SWINGS SOUTH OVER THE PLAINS
AND INTO THE MID-MISSISSIPPI VALLEY BY THURSDAY. THIS SYSTEM SHOULD
FORCE A BACKDOOR COLD FRONT INTO THE HIGH PLAINS. IT IS HARD TO TELL
HOW FAR SOUTHWEST THIS FRONT WILL REACH AND THERE IS A STRONG CHANCE
FOR A LARGE TEMPERATURE GRADIENT ACROSS THE REGION. CURRENT
THANKSGIVING FORECAST CALLS FOR A HIGH OF 38 DEGREES AT MCCOOK
NEBRASKA...44 AT GOODLAND KANSAS AND 52 AT KIT CARSON COLORADO.
MODELS TRENDED PRECIPITATION CHANCES FOR THANKSGIVING DOWN AND
BELIEVE THIS IS ACCURATE CONSIDERING A RIDGE OF HIGH PRESSURE WILL
BUILD IN FROM THE WEST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1024 PM MST FRI NOV 21 2014
FOR KGLD...VFR CONDITIONS WITH MIX OF SKC AND SCT-BKN150 AFT 12Z
SATURDAY. WINDS WSW AROUND 10KTS.
FOR KMCK...MAINLY VFR CONDITIONS WITH MIX OF SKC AND SCT-BKN150
AFT 14Z SATURDAY. MVFR FOG POSSIBLE DOWN TO 4SM AT TIMES FROM
08Z-12Z SATURDAY. WINDS WSW AROUND 10KTS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JN
SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...JN
AREA FORECAST DISCUSSION
NWS GOODLAND KS
926 PM MST FRI NOV 21 2014
.UPDATE...
ISSUED AT 926 PM MST FRI NOV 21 2014
UPDATE TO ZONES SENT OUT TO ACCOMMODATE LATEST TEMP TRENDS FROM
AREA OBS. LOW LEVEL CLOUDS COVER STILL LINGERING OVER EASTERN
EDGES OF THE FORECAST AREA AND SHOULD CONTINUE TREK EASTWARD
OVERNIGHT. THIS WILL GIVE WAY TO MID LEVEL CLOUDS WHICH ARE
CURRENTLY CENTRAL/WESTERN AREAS. LATEST EASTERN ZONES OBS ARE
STARTING TO SHOW FOG DEVELOPING...SO HAVE LEFT THAT IN OVERNIGHT.
REST OF FORECAST ON TRACK.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 138 PM MST FRI NOV 21 2014
MAIN CONCERNS ARE EXTENT OF FOG TONIGHT FOLLOWED BY HOW MUCH TO
WARM UP THE TEMPERATURES ON SATURDAY. LARGE AREA OF STRATUS AND
SOME FOG TO OUR SOUTH AND SOUTHEAST AT THIS TIME. RETURN FLOW WILL
BE IN PLACE BY THE TIME SUN GOES DOWN AND THE LOW LEVEL INVERSION
STRENGTHENS. SO WOULD EXPECT THIS MOISTURE TO BE ABLE TO RETURN
NORTH AND MOVE INTO THE AREA BEFORE THE WINDS SHIFT TO A WEST TO
SOUTHWEST DIRECTION BY LATER TONIGHT AS A SURFACE TROUGH MOVES
THROUGH.
HRRR FOLLOWED BY RAP HAVE BEEN DOING VERY WELL IN THE DEPICTION OF
THIS LOW LEVEL MOISTURE FIELD. BASED ON THAT AND THE OBSERVATIONS
TO OUR SOUTH...WENT AHEAD AND FOLLOWED THE HRRR/RAP VERY CLOSELY
FOR THE CLOUD COVER AND FOG FOR TONIGHT. FOG/LOW CLOUDS SHOULD
STAY IN THE EASTERN HALF TO TWO THIRDS OF THE AREA. IF HRRR ENDS
UP BEING RIGHT THERE COULD BE SOME DENSE FOG POSSIBLE IN THE FAR
EASTERN PORTION.
FOG AND STRATUS DECREASE LATE TONIGHT AND EARLY TOMORROW AS
SURFACE TROUGH MOVES THROUGH AND SHIFTS/INCREASES THE WINDS FROM
THE WEST. AT THIS TIME THE FOG SHOULD END BY MID MORNING. ONCE THE
FOG/CLOUDS CLEAR OFF THERE WILL BE PLENTIFUL SUNSHINE AND
DOWNSLOPE WINDS THROUGH 700 MB. COMBINATION OF DRY AIR MASS AND
GROUND COMBINED WITH THE ABUNDANT SUNSHINE AND DOWNSLOPE WINDS
WILL ALLOW FOR A GOOD WARMUP.
QUESTION IS HOW MUCH. THE NWP AND ESPECIALLY THE 2 METER GUIDANCE
HAS BEEN RUNNING COOL DURING THE LAST WEEK. AT THIS TIME WENT
ABOVE GUIDANCE IN MOST PLACES WITH 60S...MOSTLY MIDDLE AND UPPER
60S....ACROSS THE ENTIRE AREA.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 210 PM MST FRI NOV 21 2014
FOR THE EXTENDED FORECAST PERIOD...VARIABLE WEATHER CONDITIONS ARE
EXPECTED THROUGHOUT DUE TO PASSING COLD FRONTS UNDER A NORTHWEST
FLOW REGIME. OVERALL...THE PATTERN REMAINS FAIRLY CONSISTENT WITH
LITTLE CHANCE OF MAJOR PRECIPITATION-PRODUCING SYSTEMS REACHING THE
REGION. PRIMARY CHANGE TO THIS EXTENDED PACKAGE WAS TO REMOVE
PRECIPITATION CHANCES FOR THANKSGIVING. MORE DETAILS ON THIS BELOW.
FOR SATURDAY NIGHT INTO SUNDAY MORNING...A STRONG COLD FRONT PASSAGE
IS ANTICIPATED. TEMPERATURES WILL BE SLOW TO FALL SATURDAY NIGHT DUE
TO INCREASING CLOUD COVER. THEN...A QUICK DROP IN TEMPERATURES AND
GUSTY NORTH WINDS ARE LIKELY IMMEDIATELY BEHIND THE FRONT. AS THE
FRONT PASSES THROUGH...THE ATMOSPHERE MOISTENS AT LOW LEVELS WHEN
THE COOLER AIR INTRUDES. THERE SHOULD BE ENOUGH MID-LEVEL LIFT AND
MOISTURE FOR RAIN/SNOW SHOWERS DEVELOPMENT BUT THE QUESTION OVER THE
PAST FEW FORECAST RUNS HAS BEEN WHETHER OR NOT THIS PRECIPITATION
REACHES THE GROUND. BASED ON LATEST GUIDANCE...THERE SHOULD BE A
SMALL WINDOW OF OPPORTUNITY FOR MEASURABLE PRECIPITATION TO REACH
THE GROUND AHEAD OF INCOMING POST-FRONTAL DRY AIR. THEREFORE...
PLACED A SLIGHT CHANCE FOR MEASURABLE PRECIPITATION INTO THE
FORECAST AND MAINTAINED SPRINKLES/FLURRIES MENTION SURROUNDING THE
SLIGHT CHANCE POPS.
MAIN STORY FOR THE REST OF SUNDAY THROUGH MONDAY SHOULD BE
BREEZY/WINDY CONDITIONS AND COOL TEMPERATURES. WITH PERSISTENT COLD
AIR ADVECTION AND POSSIBLE CLOUD COVER OVERHEAD...HAVE A HARD TIME
BELIEVING THAT THE REGION WILL BE ABLE TO REACH MEX/MET/ECE GUIDANCE
TEMPERATURES. WENT BELOW GUIDANCE FOR HIGH TEMPERATURES DUE TO THIS
THINKING. REGARDING THE WINDS...MODELS ARE NOT IN STRONG AGREEMENT
WITH RESPECT TO HOW STRONG THE WINDS WILL BE AND WHEN THE STRONGEST
WINDS WILL OCCUR. ANY POSSIBLE CLOUD COVER ALSO MESSES WITH
ANTICIPATED MIXING HEIGHTS SO HARD TO TELL HOW STRONG THE MIXED DOWN
GUSTS WILL BE AT THIS TIME. WITHOUT A STRONG CUT-OFF LOW PRESSURE
SYSTEM PRESENT...CURRENTLY DO NOT BELIEVE THAT THIS WILL BE A MAJOR
WIND EVENT. TYPICAL COLD/WINDY HIGH PLAINS DAYS ARE FORECAST WITH
NORTH WINDS 20-30 MPH...GUSTING TO 45 MPH AND HIGH TEMPERATURES IN
THE LOW TO UPPER 40S.
BEYOND MONDAY...A WEAK UPPER LEVEL DISTURBANCE MOVES THROUGH THE
HIGH PLAINS TUESDAY INTO TUESDAY NIGHT. THE CR INITIALIZATION
PROCEDURE DID NOT INCLUDE POPS AND WITH A DRY LAYER OF AIR AT THE
SURFACE...THOUGHT THIS WAS APPROPRIATE. POPS MAY NEED TO BE INCLUDED
AT A LATER TIME BUT MODEL CONSISTENCY WAS NOT STRONG ENOUGH FOR
INCLUSION WITH THIS RUN.
ANOTHER STRONG UPPER LEVEL DISTURBANCE SWINGS SOUTH OVER THE PLAINS
AND INTO THE MID-MISSISSIPPI VALLEY BY THURSDAY. THIS SYSTEM SHOULD
FORCE A BACKDOOR COLD FRONT INTO THE HIGH PLAINS. IT IS HARD TO TELL
HOW FAR SOUTHWEST THIS FRONT WILL REACH AND THERE IS A STRONG CHANCE
FOR A LARGE TEMPERATURE GRADIENT ACROSS THE REGION. CURRENT
THANKSGIVING FORECAST CALLS FOR A HIGH OF 38 DEGREES AT MCCOOK
NEBRASKA...44 AT GOODLAND KANSAS AND 52 AT KIT CARSON COLORADO.
MODELS TRENDED PRECIPITATION CHANCES FOR THANKSGIVING DOWN AND
BELIEVE THIS IS ACCURATE CONSIDERING A RIDGE OF HIGH PRESSURE WILL
BUILD IN FROM THE WEST.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 433 PM MST FRI NOV 21 2014
KGLD WILL SEE VFR CONDITIONS THROUGH THE FORECAST PERIOD WITH A
MIX OF SKC-SCT150. WINDS SSW AROUND 10KTS.
KMCK WILL SEE MOSTLY VFR CONDITIONS WITH A MIX OF SKC AND
SCT150-250. BKN020 IS POSSIBLE FROM 02Z-04Z SAT. WINDS SOUTH
AROUND 10KTS...BECOMING WSW AROUND 10KTS BY 06Z SAT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JN
SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...JN
AREA FORECAST DISCUSSION
NWS JACKSON KY
337 AM EST SAT NOV 22 2014
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 337 AM EST SAT NOV 22 2014
THE LATEST SURFACE MAP FEATURES A LARGE AREA OF HIGH PRESSURE ACROSS
THE EASTERN CONUS...WITH LOW PRESSURE CRUISING THROUGH ONTARIO.
ALOFT...FAIRLY PROGRESSIVE FLOW IS IN PLACE...WITH A WEAKER SHORT
WAVE MOVING THROUGH THE OHIO VALLEY. A STRONGER VORT IS ROTATING
ALONG NORTHERN MEXICO...WHILE ADDITIONAL SHORT WAVE ENERGY IS MOVING
ACROSS THE PACIFIC NORTHWEST.
ANOTHER CHILLY NIGHT HAS BEEN ON TAP FOR EASTERN KENTUCKY...ALTHOUGH
NOT AS COLD AS LAST NIGHT. THERE ARE A FEW VALLEYS IN THE FAR EAST
REMAINING IN THE UPPER TEENS...WHILE LOW TO MID 20S ARE COMMON IN THE
BROADER VALLEYS. RIDGETOPS ARE IN THE 30S THANKS TO LIGHT SOUTH TO
SOUTHEAST WINDS. A DECENT 850 MB JET HAS DEVELOPED ACROSS THE OHIO VALLEY
OVERNIGHT...WITH LIGHT PRECIPITATION BREAKING OUT ACROSS MOST OF
INDIANA AND DOWN INTO WESTERN KENTUCKY. THE LATEST HRRR MAY SUPPORT A
FEW SPRINKLES ACROSS THE I-64 CORRIDOR TOWARDS DAWN...HOWEVER GIVEN
THE DRY AIR IN PLACE CHANCES OF MEASURABLE PRECIPITATION LOOK LOW.
ONCE THE SPRINKLES SKIRT BY TO THE NORTH EARLY THIS MORNING...DRY
CONDITIONS WILL REMAIN IN PLACE THANKS TO LOW LEVEL SOUTHEASTERLY
FLOW. HIGHS TODAY WILL APPROACH THE 60 DEGREE MARK IN
PLACES...TEMPERATURES THAT WE HAVE NOT SEEN IN ABOUT A WEEK AND A
HALF. MEANWHILE...NORTHERN STREAM SHORT WAVE ENERGY WILL TRAVERSE THE
U.S./CANADIAN BORDER...WHILE THE SOUTHERN STREAM VORT CONTINUES TO
SLIDE EAST. THE VORT WILL THEN SWING MORE NORTHEAST...REACHING THE
TENNESSEE VALLEY BY LATE IN THE DAY ON SUNDAY. THIS WILL RESULT IN
SURFACE LOW PRESSURE ORGANIZING ACROSS THE PLAINS...EVENTUALLY
CONGLOMERATING ACROSS THE OHIO VALLEY LATE IN THE PERIOD.
EASTERN KENTUCKY WILL ENJOY A MILDER NIGHT TONIGHT...AS WARM AIR
ADVECTION CONTINUES OUT AHEAD OF THE APPROACHING SYSTEM FROM THE
WEST. LOWS WILL BOTTOM OUT IN THE LOWER 30S IN THE MORE SHELTERED
VALLEYS IN THE EAST...WHILE OTHER LOCATIONS WILL SEE UPPER 30S AND
LOWER 40S. A WARM FRONT/MID-LEVEL SHORT WAVE WILL APPROACH THE AREA
FROM THE SOUTHWEST ON SUNDAY...WITH WIDESPREAD SHOWER ACTIVITY
BREAKING OUT ACROSS EASTERN KENTUCKY IN THE AFTERNOON. HAVE CONTINUED
TO DOWNPLAY THE QPF AMOUNTS IN THE FAR EAST WITH DOWNSLOPE FLOW IN
PLACE. DESPITE THE SHOWERS MOVING IN...HIGHS WILL MAKE IT BACK INTO
THE UPPER 50S AND LOWER 60S.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 337 AM EST SAT NOV 22 2014
STILL SOME QUESTION AS TO HOW FAST THE TROUGH AXIS SHIFTS TO THE
NORTH SUNDAY EVENING. GFS IS MUCH MORE PROGRESSIVE ON BRINGING THE
DRY SLOT IN QUICKLY SUNDAY EVENING...WHILE THE ECMWF HOLDS IT BACK
EARLY ON. BASIC THINKING IS THAT EVEN IF THE DRY SLOT MOVES IN
FASTER...WE MAY STILL GET DEVELOPMENT INTO THE WARM SECTOR THROUGH
THE NIGHT OR POSSIBLY EVEN SOME MEASURABLE DRIZZLE. THUS...WILL
MAINTAIN HIGH CHANCE TO LIKELY POPS THROUGH THE FIRST HALF OF THE
NIGHT...WITH DRIZZLE BECOMING MORE LIKELY AS THE NIGHT PROGRESSES.
ON MONDAY...A SHARP COLD FRONT WILL PUSH INTO AND CROSS THE AREA.
THIS SHOULD AGAIN BRING HIGHER CHANCES FOR SHOWERS AS IT CROSSES THE
AREA THROUGH EARLY TO MID AFTERNOON. IN THE WAKE OF THE
FRONT...TEMPERATURES WILL TAKE A TUMBLE IN THE AFTERNOON AND EVENING
HOURS. AFTER CLIMBING INTO THE LOW 60S...TEMPERATURES BY THE EVENING
SHOULD SETTLE BACK INTO THE 40S. STILL LOOKS LIKE A WINDY DAY...WITH
925MB WINDS TOPPING 35 KNOTS AS THE FRONT CROSSES THE AREA. ANY
SHOWER ACTIVITY MAY ACTUALLY HELP TO MIX DOWN SOME ISOLATED HIGHER
GUSTS TO 40 OR 45 MPH.
SURFACE HIGH PRESSURE SHOULD MOVE INTO THE OHIO RIVER VALLEY MONDAY
NIGHT WITH DRY WEATHER RETURNING. ATTENTION WILL THEN TURN TO A
POSSIBLE NOREASTER AS AN AREA OF LOW PRESSURE MOVES UP THE EASTERN
US COAST. 00Z ECMWF HAS SHIFTED THE TRACK OF THIS LOW BACK TO THE
WEST...BRINGING MOISTURE INTO THE APPALACHIAN MOUNTAINS. GOING TO
MAINTAIN THE DRY FORECAST...BUT IF THIS SYSTEM TRENDS ANY FARTHER
WEST...MAY NEED TO INSERT SOME POPS BY WEDNESDAY.
MODELS REALLY DIVERGE THEREAFTER AS WE HEAD INTO THANKSGIVING DAY.
GFS BUILDS A RIDGE OVER THE OHIO RIVER VALLEY...SUGGESTING
TEMPERATURES MAY REACH INTO THE 50S...WHILE THE ECMWF DIGS OUT
ANOTHER SHARP TROUGH AND WOULD PUT TEMPERATURES MORE INTO THE 30S
WITH A GOOD CHANCE FOR SNOW. CLEARLY THIS IS A LARGE DIFFERENCE IN
THE MODELS...AND PUTS LOTS OF UNCERTAINTY ON THE THANKSGIVING
FORECAST AND BEYOND. FOR NOW...WILL GO WITH A COMPROMISED
FORECAST...WITH A SLIGHT EDGE TOWARDS THE COLDER ECMWF AS IT HAS
BEEN VERY CONSISTENT ON THE COLDER SOLUTION. WILL ALSO MAINTAIN LOW
POPS WEDNESDAY NIGHT INTO THURSDAY NIGHT...AND GO WITH A MIXTURE OF
RAIN/SNOW THROUGH THIS PERIOD. IT DOES LOOK REGARDLESS OF
THANKSGIVING DAY...MODELS POINT TO A MUCH COLDER END TO THE
WEEK...WITH TEMPERATURES STAYING WELL BELOW NORMAL INTO FRIDAY AND
SATURDAY. WE SHOULD SEE DRIER WEATHER FOR FRIDAY AND SATURDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 105 AM EST SAT NOV 22 2014
BESIDES SOME PASSING CLOUD COVER FROM TIME TO TIME...MAINLY AT OR ABOVE
10K FEET AGL...VFR CONDITIONS WILL REIGN THROUGH THE PERIOD. WINDS
WILL REMAIN OUT OF THE SOUTH AND SOUTHEAST...REMAINING AT OR AROUND 5
KTS THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GEOGERIAN
LONG TERM...KAS
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1243 AM EST SAT NOV 22 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 406 PM EST FRI NOV 21 2014
WV IMAGERY AND RUC ANALYSIS INDICATED ZONAL MID/UPPER LEVEL FLOW
THROUGH THE NW AND N CNTRL CONUS WITH A WEAK SHORTWAVE TROUGH OVER
NORTH DAKOTA. A VIGOROUS SRN STREAM SHRTWV WAS SLIDING THROUGH SW
ARIZONA. AT THE SFC...SW FLOW WAS INCREASING FROM THE UPPER MS VALLEY
INTO THE NRN LAKES AS THE PRES GRADIENT TIGHTENS BETWEEN A 995 MB LOW
OVER MANITOBA AND 1034 MB HIGH OVER THE OH VALLEY. WAA INTO THE
REGION HAS BROUGHT AN INCREASE IN MID CLOUDS ACROSS UPPER MI WITH
ANOTHER BATCH UPSTREAM FROM MN INTO CNTRL WI. THE LOWER CLOUDS
REMAINED WELL TO THE SOUTH OVER MO AND SRN IA.
TONIGHT...EXPECT THAT THE STRONG SSW LOW LEVEL WAA PATTERN WILL
RAPIDLY BRING LOW LEVEL MOISTURE TOWARD THE AREA TO SUPPORT LOWER
CLOUDS INTO THE CWA. ALTHOUGH THE LOW LEVEL ISENTROPIC LIFT WILL BE
MARGINAL TO PRODUCE PCPN...UPSLOPE FLOW INTO MUCH OF THE AREA SHOULD
BE ENOUGH TO SUPPORT SOME LIGHT PCPN...ESPECIALLY OVER THE EAST HALF
WHERE ADDITIONAL MOISTURE FROM LAKE MICHIGAN IS AVAILABLE. MODEL
SOUNDINGS SUGGEST THAT THE 3K-8K DRY/WARM LAYER WILL BE STRONG ENOUGH
TO LIMIT/PREVENT ICE CRYSTAL AVAILABILITY INTO THE LOWER MOIST LAYER.
SO...EXPECT -FZDZ WILL BE THE PREDOMINANT PCPN TYPE. EVEN THOUGH
LITTLE IF ANY MEASURABLE PCPN IS EXPECTED...EVEN A VERY THIN COATING
OF -FZDZ COULD RESULT IN HAZARDOUS CONDITIONS ON UNTREATED ROADS.
SAT...THE COMBINATION OF DAYTIME HEATING AND ADDITIONAL WAA WILL
PUSH TEMPS ABOVE FREEZING IN MOST AREAS BY NOON CHANGING ANY
LINGERING FREEZING DRIZZLE TO DRIZZLE. EXPECT THE PCPN CHANCES TO
DIMINISH AS THE LOW LEVEL WAA WEAKENS DURING THE LATE MORNING AND
AFTERNOON. OTHERWISE...TEMPS SHOULD CLIMB TO READINGS AT OR ABOVE
NORMAL IN THE MID TO UPPER 30S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 430 PM EST FRI NOV 21 2014
A VERY ACTIVE WEEK IS IN STORE ACROSS THE UPPER GREAT LAKES AS A
POTENT MID-LEVEL SYSTEM DIGS INTO THE NORTHERN ROCKIES/PLAINS. THIS
WILL BRING A DECENT SURGE OF WARM AIR ACROSS THE AREA BY LATE
WEEKEND...BRINGING THE AREA BACK INTO ABOVE-AVERAGE TEMPERATURES FOR
A SHORT PERIOD. WITH THIS WILL COME A DECENT ROUND OF RAIN ACROSS
MAINLY CENTRAL AND EASTERN UPPER MI SUNDAY NIGHT INTO MONDAY. A
QUICK TRANSITION BACK TO WINTER WILL THEN TAKE PLACE ON MONDAY AS
THE TROUGH AND ASSOCIATED STRONG SURFACE LOW MOVE NORTHEAST OF THE
REGION...BRINGING STRONG CAA AND THE POTENTIAL FOR A DECENT SNOWFALL
ACROSS THE WESTERN CWA.
SATURDAY NIGHT...AS WEAK MID-LEVEL RIDGING WORKS ACROSS THE UPPER
GREAT LAKES...THIS LOOKS TO BE THE QUIETEST PERIOD THROUGH AT LEAST
TUESDAY. SIGNIFICANTLY DRY AIR ABOVE 900 HPA AND THE LACK OF ANY
APPRECIABLE MID/UPPER-LEVEL FORCING SHOULD LIMIT ANY DEEPER PRECIP
POTENTIAL. THE ONLY CONCERN IS A CHANCE FOR DZ/FZDZ ASSOCIATED WITH
WEAK LOW-LEVEL WAA SOUTH LATE IN THE NIGHT.
SUNDAY AND MONDAY...SIGNIFICANT CHANGES ARE SET TO BEGIN SUNDAY AS
AN ACTIVE NORTHERN AND SOUTHERN STREAM TAKE AIM ON THE UPPER GREAT
LAKES. FIRST...A LOOK AT THE LARGE SCALE PICTURE. AS THE
AFOREMENTIONED TROUGH OVER THE NORTHERN ROCKIES TRACKS ESE TOWARD
THE UPPER MS VALLEY...ANOTHER TROUGH ACROSS TX SATURDAY EVENING WILL
EJECT NE INTO THE UPPER GREAT LAKES. THE MERGING PIECES OF ENERGY
COMBINED WITH A QUICKLY DEVELOPING 120KT UPPER JET STREAK WILL
INDUCE A SFC LOW SOMEWHERE FROM EASTERN UPPER MI TO NORTHERN LOWER
MI BY 12Z MONDAY.
UPPER MI FINDS ITSELF CAUGHT IN A CONVOLUTED PATTERN SUNDAY MORNING
BEFORE THE TWO SYSTEMS CONSOLIDATE OVER THE AREA. OVERALL SYNOPTIC
FORCING REMAINS LIMITED TO START THE DAY...BUT LOW-LEVEL MOISTURE
TRANSPORT RESULTING IN A DEEPENING MOIST LAYER WILL ALLOW FOR
INCREASING CHANCES OF FZDZ/DZ IN THE MORNING...AND RAIN THROUGHOUT
THE AFTERNOON. BEST CHANCES DURING THE DAY LOOK TO BE ACROSS THE
CENTRAL AND EASTERN CWA WITH UPSLOPE AND MOISTURE INFLUENCES FROM SE
WINDS OFF LAKE MI. TEMPS THROUGH THE MOIST LAYER WILL REMAIN WARM
ENOUGH FOR SUPER-COOLED LIQUID...INTRODUCING CONTINUED CONCERN FOR
FZDZ/FZRA IN THE MORNING. GIVEN OUR RECENT SUB-FREEZING
STRETCH...CLEARED ROADS MAY SEE SOME ICING EVEN AS TEMPS WARM INTO
THE 30S TO LOW 40S DURING THE DAY SUNDAY. LATEST MDOT ROAD SENSORS
ARE SHOWING SUB-FREEZING TEMPS DOWN AT LEAST 24 INCHES BELOW THE
ROAD AND SUB-20F TEMPS DOWN TO AT LEAST 6 INCHES FOR NEARLY ALL
UPPER MI HIGHWAYS. WILL THEREFORE EXTEND THE FZDZ/FZRA POTENTIAL
THROUGH SUNDAY MORNING UNTIL AIR TEMPS WARM WELL-ABOVE FREEZING
SUNDAY AFTERNOON.
SIGNIFICANT MOISTURE TRANSPORT/ISENTROPIC LIFT WILL FOCUS ACROSS THE
EAST HALF OF THE CWA LATE SUNDAY AFTERNOON THROUGH MUCH OF THE
NIGHT. MEANWHILE...DECENT LIFT UNDER THE RIGHT ENTRANCE OF THE UPPER
JET WILL SPREAD ACROSS THE AREA. THIS SHOULD BRING WIDESPREAD PRECIP
OVER THE ENTIRE CWA THROUGHOUT THE NIGHT. WARMING TEMPS THROUGHOUT
THE COLUMN WILL RESULT IN A PTYPE OF ALL RAIN FOR THE ENTIRE CWA
SUNDAY AFTERNOON AND EVENING...AND ALL BUT THE WESTERN CWA LATE
SUNDAY NIGHT. WITH THE DECENT FORCING AND SUFFICIENT
MOISTURE...RAINFALL AMOUNTS LATE SUNDAY AFTERNOON THROUGH MONDAY
MORNING ARE EXPECTED TO SURPASS 0.75IN ACROSS THE EAST HALF. THIS
MAY BE A LITTLE CONSERVATIVE...BUT WOULD LIKE TO SEE BETTER
MID-LEVEL SUPPORT IN CONJUNCTION WITH THE UPPER JET BEFORE
INCREASING PRECIP AMOUNTS ANY FURTHER.
LATE SUNDAY NIGHT INTO MONDAY STARTS THE TRANSITION BACK TO SNOW AS
THE SFC LOW REACHES EASTERN UPPER MI LATE SUNDAY NIGHT. AS THE
SOUTHERN AND NORTHERN STREAM MERGE...THE NEW DEEPER TROUGH NEARLY
STALLS OVER THE UPPER GREAT LAKES. AN IMPRESSIVE 140KT UPPER JET
OVER THE MID MS VALLEY COMBINED WITH THE DEPARTING 120KT JET MOVING
OVER QUEBEC WILL BE ENOUGH TO KEEP A DEEPER SFC LOW OVER
ONTARIO/QUEBEC. MEANWHILE...A COMPACT TROUGH NEAR SEATTLE SUNDAY
AFTERNOON WILL DIG INTO THE DEPARTING THE TROUGH...FURTHER SLOWING
ITS MOVEMENT. ALL OF THIS COMES TOGETHER TO PRODUCE A LAGGING
LOW-LEVEL TROUGH AND DEFORMATION ZONE OVER UPPER MI ON MONDAY AND
MONDAY NIGHT. WITH LAKE ENHANCEMENT KICKING IN WITH N/NNW
WINDS...THERE IS INCREASING POTENTIAL FOR MODERATE TO POSSIBLY HEAVY
SNOW ACROSS THE NORTHWEST HALF OF UPPER MI. THE 12Z NAM AND 12Z GFS
HAVE BOTH COME IN WITH MUCH HIGHER QPF ACROSS THE WESTERN AND
CENTRAL CWA ON MONDAY. THOUGH THE ECMWF TAKES THE LOW ACROSS
NORTHERN LOWER MI...THE MID/UPPER-LEVEL SUPPORT PAINTS HIGHER QPF
AMOUNTS ACROSS THE WESTERN CWA AS WELL. THE TRANSITION TO SNOW
SHOULD BE UNDERWAY ACROSS THE FAR WEST BY DAYBREAK MONDAY...THEN
CONTINUE PRESSING EASTWARD. BY EARLY AFTERNOON...ALL BUT SOME OF THE
SHORELINE LOCATIONS OF THE WEST HALF SHOULD CHANGE OVER TO SNOW.
WHILE THERE IS SOME UNCERTAINTY IN HOW QUICK SNOW RATIOS INCREASE
DURING THE DAY...SEVERAL INCHES OF SNOW SHOULD FALL FOR MOST OF THE
NW HALF OF THE CWA MONDAY AFTERNOON. DO NOT WANT TO COMPLETELY JUMP
ON BOARD WITH THE NEW GUIDANCE QUITE YET...BUT THERE IS ENOUGH
EVIDENCE TO AT LEAST INCREASE SNOW AMOUNTS A BIT. THE EASTERN CWA
SHOULD SEE AT LEAST SOME ACCUMULATIONS...BUT A LATER TRANSITION TO
ALL SNOW COMBINED WITH A LESS FAVORABLE LOCATION OF THE FORCING WILL
KEEP AMOUNTS LOWER. WILL NEED TO MONITOR THIS OVER THE NEXT COUPLE
DAYS AS AT LEAST SOME WINTER WX HEADLINES MAY BE NEEDED.
MONDAY NIGHT AND TUESDAY...MOISTURE CONTINUING TO WRAP AROUND
THE BACKSIDE OF THE DEPARTING LOW COMBINED WITH UPSLOPE AND LAKE
INFLUENCE WILL GENERATE SNOW FOR THE N TO NNW WIND SNOW BELTS.
ANOTHER SEVERAL INCHES OF SNOW WILL BE POSSIBLE MONDAY NIGHT. BY
TUESDAY...SOME DRIER AIR WILL BEGIN TO WORK IN FROM THE WEST AS
INVERSION HEIGHTS FALL BELOW 5KFT...CUTTING OFF MUCH OF THE RESIDUAL
LAKE EFFECT PRECIP.
WEDNESDAY THROUGH FRIDAY...ANOTHER TROUGH DIGGING OUT OF
NORTH-CENTRAL CANADA WILL MOVE SE ACROSS THE UPPER GREAT LAKES
TUESDAY NIGHT INTO WEDNESDAY. ACCUMULATING SNOW WILL BE POSSIBLE
WEDNESDAY WITH THIS SYSTEM...BUT ITS TRACK AND STRENGTH ARE TOO
VARIABLE IN THE MODELS TO PIN DOWN LOCATIONS AT THIS TIME. MUCH
COLDER AIR ARRIVES BEHIND THE LOW AND INDUCES LES FOR THE NNW WIND
SNOW BELTS WEDNESDAY NIGHT THROUGH THANKSGIVING. A SLOWLY MODERATING
850 HPA AIRMASS WITH TEMPS -15 TO -20C WILL RESULT IN THE WEATHER
FEELING MORE LIKE CHRISTMAS THAN THANKSGIVING AS HIGHS STRUGGLE TO
GET OUT OF THE TEENS FOR AT LEAST THE WEST AND CENTRAL. BY
FRIDAY...ANOTHER PATTERN CHANGE WILL BRING MODERATING CONDITIONS TO
END THE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1243 AM EST SAT NOV 22 2014
LLWS IS EXPECTED AS THE LOW LEVEL JET REALLY INCREASES 1-2KFT ABOVE
THE SURFACE...ESPECIALLY AT KSAW OVERNIGHT. HAVE LEFT GUSTS UP TO
ACCOUNT FOR THIS. MVFR CLOUDS WILL BE PUSHING NORTH-NORTHEAST INTO
THE AREA TONIGHT. THIS WILL LEAD TO A QUICK DROP IN CEILINGS LATE
TONIGHT...WITH KSAW HAVING THE LOWEST VALUES THAT SHOULD FALL INTO
THE IFR RANGE LATE. WITH THESE LOW CLOUDS...THERE IS THE POTENTIAL
FOR LIGHT FREEZING DRIZZLE LATE TONIGHT...ESPECIALLY AT KSAW.
CURRENT SFC DEWPOINT DEPRESSIONS REMAIN HIGH THOUGH AT 10-15F...SO
WILL NOT MENTION FZDZ ATTM. CONDITIONS AT ALL SITES ON SAT WILL BE
LOW MVFR OR IFR AT ALL SITES AS LOW CLOUDS REMAIN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 406 PM EST FRI NOV 21 2014
WINDS WILL CONTINUE TO INCREASE WITH A TIGHT PRES GRADIENT BETWEEN
LOW PRES OVER THE PLAINS AND A RIDGE OVER THE OH VALLEY.
WINDS TOT 30KTS WITH FREQUENT GALE FORCE GUSTS TO 35 KNOTS ARE
EXPECTED TONIGHT. THE PRESSURE GRADIENT WILL DECREASE SATURDAY INTO
SATURDAY NIGHT AS A TROUGH TRAILING THE CANADIAN LOW DROPS SOUTHEAST
OVER LAKE SUPERIOR. A DEVELOPING LOW IN THE CENTRAL/SOUTHERN PLAINS
ON SATURDAY NIGHT WILL LIFT NORTHEAST THROUGH THE GREAT LAKES REGION
TO NEAR THE STRAITS MONDAY MORNING AT AROUND 28.9 INCHES. AS THE LOW
LIFTS TO THE NORTHEAST ON MONDAY NORTHERLY GALES ARE LIKELY WHICH
COULD PERSIST THROUGH MONDAY NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 AM EST /6 AM CST/ THIS MORNING FOR LSZ162-
263-264-266-267.
LAKE MICHIGAN...
GALE WARNING UNTIL 10 AM EST THIS MORNING FOR LMZ248.
&&
$$
SHORT TERM...JLB
LONG TERM...KLUBER
AVIATION...07/JLA
MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1137 PM CST FRI NOV 21 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 422 PM CST FRI NOV 21 2014
THERE ARE A COUPLE FORECAST CHALLENGES OVER THE NEXT FEW DAYS. THE
FIRST: IS THE SLIGHT CHANCE FOR LIGHT FREEZING RAIN OR FREEZING
DRIZZLE IN FAR EASTERN MN AND WEST CENTRAL WI TONIGHT. THE SECOND:
IS THE MIXED P-TYPE AND WIND EVENT SUNDAY INTO MONDAY.
THERE HAS BEEN A STEADY STREAM OF HIGH CLOUDS TODAY...BUT THERE IS A
LOW STRATUS DECK STREAMING NORTH ACROSS SOUTHERN NE/IA THIS
AFTERNOON. THESE CLOUDS ARE TIED TO LOW LEVEL MOISTURE ADVECTION OUT
AHEAD OF AN ADVANCING SHORTWAVE CURRENTLY TRANSVERSE THE NORTHERN
PLAINS THIS AFTERNOON. WE THINK THERE WILL BE DEEPER SATURATION AND
BETTER OMEGA TO THE SOUTH AND WEST OF THE FORECAST AREA THIS EVENING
AND TONIGHT /BASICALLY INN AREAS CURRENTLY UNDER A FREEZING RAIN
ADVISORY/. THE SREF PROBABILITIES OF FREEZING RAIN/DRIZZLE ARE ON
THE ORDER OF 40-80% IN THESE AREAS. LOCALLY...WE`RE NOT CONFIDENT IN
MUCH ELSE BESIDES A HEALTHY STRATUS DECK AND PERHAPS SOME LIGHT FOG
AS THE STRATUS LOWERS. WE MAINTAINED LOW PROBS OF PRECIP IN EASTERN
PORTIONS OF THE FORECAST AREA WITH A MIX...AND IT ONLY TAKES A SMALL
AMOUNT OF FREEZING RAIN/DRIZZLE TO CAUSE PROBLEMS...BUT AS OF RIGHT
NOW THE BETTER LIFT AND DEEPER MOISTURE IS SOUTHEAST OF THE FORECAST
AREA. WE FOLLOWED THE LATEST REFLECTIVITY TRENDS OF THE HRRR...WHICH
MATCH UP REASONABLY WELL WITH THE 0.5KM CONDENSATION PRESSURE
DEFICITS OFF THE 20Z-22Z RAP.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 422 PM CST FRI NOV 21 2014
SPLIT FLOW WILL KEEP THE AREA LARGELY DRY INTO SUNDAY AFTERNOON
AS THE SOUTHERN STREAM LIFTS A TROUGH NORTHWARD FROM THE SOUTHERN
PLAINS INTO THE MID MISSISSIPPI VALLEY ON SUNDAY WHILE A TROUGH
DIGS INTO THE NORTHERN HIGH PLAINS ALONG THE NORTHERN STREAM.
THE NEXT MOIST SURGE MOVES IN WITH A STRONG WARM FRONT SATURDAY
EVENING AND OVERNIGHT. MODEL SIGNALS OF WARM FRONTAL
LIFT...850MB MOISTURE TRANSPORT CONVERGENCE...AND MOISTURE
ADVECTION INDICATE A FAIRLY HIGH LIKELIHOOD OF RAIN...PROBABLY
HIGHER THAN GUIDANCE INDICATES. AT THIS TIME...IT APPEARS THE
MODEL CONSENSUS AGREES THAT ONLY MINOR PRECIPITATION WOULD GO INTO
SNOW SUNDAY NIGHT AS COLDER AIR MOVES IN. THE FORECAST
SOUNDINGS...ESPECIALLY OFF THE NAM SHOW 35-40KTS AT THE TOP OF THE
MIXED LAYER WITH STEEP LOW LEVEL LAPSE RATES FOR 12-15 HOURS
SUNDAY NIGHT AND MONDAY. THE CONDITION OF THE SNOWPACK WILL BE IN
QUESTION IN THE EAST WITH THE SLIGHTLY WARMER TEMPS AND CHANCE FOR
RAIN...BUT WESTERN MN WILL REMAIN MUCH COOLER AND WE COULD ALSO
PICK UP A HIGH RATIO 0.5-2.0" IN SPOTS...SO THE THREAT FOR BLOWING
SNOW IS STILL A CONCERN IN WESTERN MN. WINTER HEADLINES ARE STILL
POSSIBLE FOR THIS PERIOD. ANOTHER COLD PERIOD BEGINS MONDAY AND
CURRENT THANKSGIVING HIGHS ARE IN THE TEENS AS A COLD AIR MASS
SETTLES IN AFTER A WEAK SYSTEM WEDNESDAY. THIS AIR MASS IN THE
NAEFS AND GEFS IS ABOUT 2 STANDARD DEVIATIONS BELOW NORMAL FOR
THURSDAY. THE OPERATIONAL RUNS ARE ALSO QUITE COLD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1046 PM CST FRI NOV 21 2014
LOW CLOUDS ARE CURRENTLY BEING ADVECTED NORTHWARD THROUGH SOUTHEAST
MN AND WESTERN WI. THIS STRATUS DECK WILL CONTINUE TO OVERSPREAD
EASTERN TERMINALS...WHERE IFR CIGS WILL DEVELOP WITHIN THE NEXT
COUPLE HOURS. THE LOW STRATUS DECK OVER EASTERN TERMINALS SHOULD
BUILD NORTHWESTWARD BY SATURDAY MORNING...AND IFR/LIFR CIGS COULD
DEVELOP OVER ALL TERMINALS BY THIS TIME. THE POTENTIAL FOR PATCHY
FOG ALSO EXISTS...AS THE HRRR AND HOPWRF SHOW VISIBILITIES LESS THAN
A MILE ACROSS THE REGION SATURDAY MORNING. WHILE THERE IS STILL SOME
DISAGREEMENT...MOST MODELS SHOW THE POTENTIAL FOR A PROLONGED PERIOD
OF IFR/LIFR CIGS AT ALL TERMINALS THROUGH SATURDAY EVENING AS WARM
MOIST AIR IS ADVECTED OVER THE SNOW PACK.
KMSP...IFR CIGS WILL DEVELOP WITHIN THE NEXT COUPLE HOURS AS A LOW
CLOUD DECK DEVELOPS. IFR/LIFR CIGS AND REDUCED VISIBILITIES ARE
LIKELY SATURDAY MORNING THROUGH THE EVENING AS LOW CLOUDS AND
POSSIBLY PATCHY FOG PERSIST. MEASURABLE PRECIP SHOULD REMAIN TO THE
SOUTHEAST ON SATURDAY WITH SOME PATCHY DRIZZLE POSSIBLE IN THE
EVENING...THOUGH CHANCES OF PRECIPITATION REMAIN LOW.
/OUTLOOK FOR KMSP/
SUN...MVFR/IFR WITH FZDZ/-RA POSSIBLE. WINDS SE 10 KT.
MON...MVFR/IFR WITH -SN/BLSN POSSIBLE. WINDS NW 25G30 KT.
TUES...VFR/MVFR WITH -SN POSSIBLE EARLY. WINDS NW 10 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...CLF
LONG TERM...CLF
AVIATION...ADL
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1210 AM CST Sat Nov 22 2014
.UPDATE:
Issued at 1008 PM CST Fri Nov 21 2014
Weak lift and mid level moisture associated with a low-amplitude shortwave
currently located in western MO combined with lift via a southwesterly
LLJ has generated some showers this evening. These showers were
currenly located to the west of the MS river across southwest and
south central IL, moving to the northeast at 30-35 kts. The showers
should exit the CWA by midnight as the shortwave continues to
migrate eastward in the west-southwest flow aloft, also taking the
mid level moisture with it. In its wake during the overnight
hours, the atmosphere will be bottom heavy with moisture confined
to the low levels. This moisture stratification along with continued
weak ascent via low level WAA would support patchy light rain or
drizzle. Accordingly I have lowered pops a bit and refined the
precipitation mode.
Glass
&&
.SHORT TERM: (Through Late Tonight)
Issued at 349 PM CST Fri Nov 21 2014
Will continue the chance of light rain as low level moisture
convergence and large scale ascent increases ahead of shortwave
trough currently moving towards us across the central Plains. There
are two small areas of rain that have developed ahead of this
system...one over west central Missouri which will move into central
and northeast Missouri later this afternoon and a second over
northern Arkansas which will move into southeast Missouri. Rain
chances will increase areawide this evening as aforementioned trough
moves across Missouri and Illinois. Chances will continue through
the night as a 50kt low level jet sets up over the region which will
provide more low level moisture convergence. At this time it still
appears that precipitation from this event will be mostly liquid as
dewpoints are steadily rising as rain moves into the area. Both the
HRRR and RUC are showing that the surface wet-bulb temperatures will
be at or above freezing during the onset of precipitation through
early this evening with temperatures continuing to rise through the
late evening hours.
Britt
.LONG TERM: (Saturday through Next Friday)
Issued at 349 PM CST Fri Nov 21 2014
At least scattered light showers can be expected Saturday and
Saturday night due to low-mid level warm air advection and as a
southwesterly low level jet continues to bring low level moisture
into the area. The best chance of rain along with the highest
rainfall amounts should occur on Sunday as a southern stream
negatively tilted shortwave moves through the southern Plains and
into the TN Valley region, while an upper level low moves
southeastward into the northern Plains. There will be upper level
divergence over our area between an upper level jet streak across
the southern Plains and another upper level jet streak across the
Great Lakes region. A surface low will develop and deepen as it
moves northeastward through the St Louis area around 00z Monday.
There should be at least isolated thunderstorms across portion sof
central and southeast MO and southwest IL. Temperatures will be
much warmer this weekend and above normal for a change. Much of the
precipitation should shift east of our forecast area Sunday night as
colder and drier air filters southeastward into the region behind
the surface low and trailing cold front. There may be some
lingering precipitation Sunday night into Monday morning as
shortwaves move through the area south of the upper level low which
will progress slowly eastward into the Great Lakes region. The rain
may change over to some light snow across northeast MO and west
central IL late Sunday night and Monday as colder air continues to
advect into the region. Temperatures will return to below normal
values beginning Monday with both the GFS and ECMWF models dropping
the -8 degree C 850 mb isotherm down to STL by 18z Monday. Below
normal temperatures are expected from Monday through Thanksgiving
with little if any precipitation as a deep upper level trough moves
slowly eastward through the central US. The ECMWF model does drop a
northwest flow, clipper type shortwave and associated weak surface
low southeastward through our area which could bring the potential
for a brief period of snow on Wednesday, but the GFS is much weaker
with this feature and only has very light QPF. A strong surface
ridge will build southeastward into MO for Wednesday night and
Thanksgiving Day with unseasonably cold temperatures expected.
GKS
&&
.AVIATION: (For the 06z TAFs through 06z Saturday Night)
Issued at 1134 PM CST Fri Nov 21 2014
MVFR conditions are expected to prevail overnight and for most of
tomorrow. Some improvement is possible at KCOU between 22/21z and
23/06z before conditions deteriorate again. Light drizzle is
possible overnight. Widespread rain is likely just beyond the end
of the 24-hr TAF period.
Specifics for KSTL: Although conditions may occasionally lift to
VFR for brief periods overnight, MVFR cigs are expected to prevail
until mid to late morning. Light drizzle is also possible.
Widespread rain is likely towards the end of the 30-hr TAF period
and beyond.
Kanofsky
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1131 PM CST Fri Nov 21 2014
.UPDATE...
Issued at 912 PM CST FRI NOV 21 2014
Trimmed back overnight PoPs as deeper moisture as noted in IR
satellite imagery and radar returns is peeling off to the northeast.
00z NAM and RUC h7 condensation pressure deficit progs support this
as does the miniscuel reflectivity returns on the HRRR. Bufr
soundings are more supportive of drizzle forming overnight. Will
stratify PoPs with best chances for rain over the southeast 1/3 of
the CWA. Deeper moisture doesn`t arrive from teh southwest until
later Saturday afternoon so until then think low chance PoPs the best
one can do.
&&
.DISCUSSION...
Issued at 309 PM CST FRI NOV 21 2014
Main concern in the short term will be fog, stratus, and light
showers as a broad area of warm air advection continues across the
region. Without a strong focus for lift, any precipitation tonight
into Saturday should be fairly light throughout the region. Dense
fog looks likely mainly across eastern Kansas and northwest MO where
moisture will remain fairly shallow; farther to the southeast, low
stratus and continued isolated showers seem more likely. May need a
dense fog advisory in far western and northwestern portions of the
CWA tonight, but will wait to see how efficiently fog develops later
this evening. Another round of dense fog looks possible on Saturday
night across far northern MO and especially further to the north in
IA, with continued stratus to the south.
Rain will become more widespread for Sunday as a shortwave trough
lifts out of the southern Plains and into eastern MO, and a surface
low tightens up over central portions of the state. Rain is most
likely and potential precipitation totals are highest across far
eastern portions of the CWA, but at least some rainfall is likely as
far west as the KC metro during the daylight hours. Timing for the
exit of this system is still a little uncertain, but rain should be
tapering off by late Sunday evening into the early morning hours
Monday. A second system is still also expected to sweep in from the
northern Plains on Sunday, bringing colder air into northern MO by
late Sunday and into the remainder of the state on Monday. Rain may
briefly mix with or change over to snow in northern MO late Sunday
night or early Monday as the first system departs and cold air
surges in, but warm/wet ground and depleted moisture will prevent
any snow accumulation.
Colder temperatures are expected Monday and Tuesday as the second
system continues to dive southeast and allows Canadian air to filter
into the central CONUS; then some brief warming is possible
Wednesday as that system departs. The latest 2 runs of both the EC
and GFS have finally come into much better alignment for Thursday
and Friday, indicating a rather cold but dry Thanksgiving, but a
quick warm up for Friday beyond the end of the period. Have removed
all PoPs beyond the weekend system, leaving the long-range forecast
period dry.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday Night)
Issued at 1118 PM CST FRI NOV 21 2014
Surface conditions beginning to degrade as moisture from the south
continues to work its way north. Will see the onset of fog
development during the overnight hours initiating IFR ceilings with
a period of LIFR ceiling heights shortly thereafter. Not much anticipated
in the way of precipitation other than light drizzle coupled with the
fog. IFR ceilings expected to persist throughout the morning while
increased chances of precipitation will commence in the afternoon.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
UPDATE...MJ
DISCUSSION...Laflin
AVIATION...Welsh
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1013 PM CST Fri Nov 21 2014
.UPDATE:
Issued at 1008 PM CST Fri Nov 21 2014
Weak lift and mid level moisture associated with a low-amplitude shortwave
currently located in western MO combined with lift via a southwesterly
LLJ has generated some showers this evening. These showers were
currenly located to the west of the MS river across southwest and
south central IL, moving to the northeast at 30-35 kts. The showers
should exit the CWA by midnight as the shortwave continues to
migrate eastward in the west-southwest flow aloft, also taking the
mid level moisture with it. In its wake during the overnight
hours, the atmosphere will be bottom heavy with moisture confined
to the low levels. This moisture stratification along with continued
weak ascent via low level WAA would support patchy light rain or
drizzle. Accordingly I have lowered pops a bit and refined the
precipitation mode.
Glass
&&
.SHORT TERM: (Through Late Tonight)
Issued at 349 PM CST Fri Nov 21 2014
Will continue the chance of light rain as low level moisture
convergence and large scale ascent increases ahead of shortwave
trough currently moving towards us across the central Plains. There
are two small areas of rain that have developed ahead of this
system...one over west central Missouri which will move into central
and northeast Missouri later this afternoon and a second over
northern Arkansas which will move into southeast Missouri. Rain
chances will increase areawide this evening as aforementioned trough
moves across Missouri and Illinois. Chances will continue through
the night as a 50kt low level jet sets up over the region which will
provide more low level moisture convergence. At this time it still
appears that precipitation from this event will be mostly liquid as
dewpoints are steadily rising as rain moves into the area. Both the
HRRR and RUC are showing that the surface wet-bulb temperatures will
be at or above freezing during the onset of precipitation through
early this evening with temperatures continuing to rise through the
late evening hours.
Britt
.LONG TERM: (Saturday through Next Friday)
Issued at 349 PM CST Fri Nov 21 2014
At least scattered light showers can be expected Saturday and
Saturday night due to low-mid level warm air advection and as a
southwesterly low level jet continues to bring low level moisture
into the area. The best chance of rain along with the highest
rainfall amounts should occur on Sunday as a southern stream
negatively tilted shortwave moves through the southern Plains and
into the TN Valley region, while an upper level low moves
southeastward into the northern Plains. There will be upper level
divergence over our area between an upper level jet streak across
the southern Plains and another upper level jet streak across the
Great Lakes region. A surface low will develop and deepen as it
moves northeastward through the St Louis area around 00z Monday.
There should be at least isolated thunderstorms across portion sof
central and southeast MO and southwest IL. Temperatures will be
much warmer this weekend and above normal for a change. Much of the
precipitation should shift east of our forecast area Sunday night as
colder and drier air filters southeastward into the region behind
the surface low and trailing cold front. There may be some
lingering precipitation Sunday night into Monday morning as
shortwaves move through the area south of the upper level low which
will progress slowly eastward into the Great Lakes region. The rain
may change over to some light snow across northeast MO and west
central IL late Sunday night and Monday as colder air continues to
advect into the region. Temperatures will return to below normal
values beginning Monday with both the GFS and ECMWF models dropping
the -8 degree C 850 mb isotherm down to STL by 18z Monday. Below
normal temperatures are expected from Monday through Thanksgiving
with little if any precipitation as a deep upper level trough moves
slowly eastward through the central US. The ECMWF model does drop a
northwest flow, clipper type shortwave and associated weak surface
low southeastward through our area which could bring the potential
for a brief period of snow on Wednesday, but the GFS is much weaker
with this feature and only has very light QPF. A strong surface
ridge will build southeastward into MO for Wednesday night and
Thanksgiving Day with unseasonably cold temperatures expected.
GKS
&&
.AVIATION: (For the 00z TAFs through 00z Saturday Evening)
Issued at 522 PM CST Fri Nov 21 2014
MVFR cigs are expected to prevail overnight, however there may be
occasional brief periods of low-end VFR ceilings. Widely scattered
rain showers are possible through the period, especially at KCOU and
KUIN. A 50kt southwesterly LLJ will likely produce LLWS conditions
at all terminals between 05-14z.
Specifics for KSTL: MVFR cigs are expected to prevail overnight,
however there may be occasional brief periods of low-end VFR
ceilings. Widely scattered rain showers are possible through the
period. The highest rain chances at KSTL are expected beyond the
end of the 30-hr TAF period. A 50kt southwesterly low level jet
will likely produce LLWS conditions between 05-14z.
Kanofsky
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1200 AM CST SAT NOV 22 2014
.UPDATE...
ISSUED AT 1058 PM CST FRI NOV 21 2014
UPDATED THE FORECAST TONIGHT TO HIT THE FOG HEAVIER AND ADD A
LITTLE DRIZZLE TO MOST OF THE CWA. STRATUS HAS MADE IT FARTHER
NORTH THAN ORIGINALLY FORECAST. HRRR SEEMS TO HAVE A GOOD GRIP ON
THIS AND BEGINS TO MOVE THE STRATUS SOUTHEAST LATE TONIGHT BUT
HANGS ONTO IT IN OUR FAR SOUTHEAST INTO THE MORNING HOURS. THIS
WILL HOLD TEMPS UP DOWN THERE AND I HAVE RAISED LOWS. ANY
DRIZZLE/STRATUS WILL BE ABOVE FREEZING ACCORDING TO THE DEPENDABLE
HRRR AND I HAVE NO REASON TO DOUBT THIS...SO FREEZING DRIZZLE
SHOULD NOT BE A PROBLEM.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM CST FRI NOV 21 2014
HAVE SEEN QUIET CONDITIONS ACROSS THE CWA TODAY...WITH UPPER AIR
AND SATELLITE IMAGERY SHOWING A WEAK UPPER LEVEL DISTURBANCE
MAKING ITS WAY ACROSS THE REGION...WHILE A STRONGER LOW PRESSURE
SYSTEM SPINS OVER THE DESERT SW. AT THE SFC...THE CWA IS SET UP
BETWEEN HIGH PRESSURE CENTERED OVER THE ERN THIRD OF THE CONUS AND
A TROUGH OF LOW PRESSURE DRAPED THROUGH THE HIGH
PLAINS...RESULTING IN CONTINUED SRLY WINDS. VISIBLE SATELLITE
IMAGERY SHOWS A EXPANSIVE AREA OF LOW LEVEL STRATUS WHICH HAS BEEN
GRADUALLY MAKING ITS WAY NORTH THROUGH THE DAY...AND IN THE PAST
FEW HOURS HAS FINALLY MADE IT INTO THE SRN PORTIONS OF THE CWA.
THE LOWER LEVEL RH FIELDS OF THE RAP/NAM HAVE BEEN HANDLING ITS
PROGRESSION WELL TODAY. TEMPS HAVE WARMED A BIT MORE THAN EXPECTED
TODAY...3 PM OBS RANGE FROM THE LOWER 50S IN THE ODX/LXN/PHG
AREAS...MID TO UPPER 40S CENTRAL AND LOCATIONS EAST ALONG THE
STATE LINE...STILL SOME UPPER 30S IN THE NORTHEAST CORNER.
THROUGH THE OVERNIGHT HOURS TONIGHT INTO THE FIRST PART OF
SATURDAY MORNING...THE MAIN CONCERN IS GOING TO LIE WITH THIS
CLOUD COVER...AND FOG POTENTIAL. WILL STICK CLOSE TO THE NAM/RAP
FOR THE EVOLUTION OF THE LL STRATUS...WHICH KEEPS CREEPING IT
NORTH...THEN GIVES IT A SHOVE OFF TO THE EAST THROUGH THE EVENING
HOURS. EXPECTING LITTLE CHANGE WITH THE OVERALL SFC
PATTERN...WINDS REMAINING SRLY WITH SPEEDS ARND 10 MPH. MODELS
THIS MORNING STARTING SHOWING BETTER POTENTIAL FOR THE DEVELOPMENT
OF FOG...MAINLY ACROSS THE ERN HALF OF THE CWA...AREAS AFFECTED BY
STRATUS TODAY OR ON THE EDGE OF THE STRATUS TONIGHT. MET/MAV/LAV
NOT LENDING MUCH SUPPORT TO LOWER VISIBILITIES OR CEILINGS...BUT
DID INSERT A MENTION OF PATCHY AND AREAS OF FOG...MAINLY AFTER
MIDNIGHT. EVENING CREW WILL BE MONITORING TRENDS CLOSELY...AS
MODELS DEPICTED LOCATIONS OUTSIDE OF THE CWA BEING AFFECT
FIRST...WILL SEE HOW THINGS PLAY OUT.
FOR TOMORROW...OUTSIDE OF THE POSSIBILITY OF SOME LINGERING FOG IN
THE MORNING...DRY CONDITIONS ARE EXPECTED. THAT MAIN UPPER LEVEL
LOW PRESSURE SYSTEM SHIFTS OUT OF THE DESERT SW...BUT BY THE END
OF THE DAY STILL REMAINS WELL SOUTH OF THE CWA IN TX. AM BEING
OPTIMISTIC WITH THE CLOUD COVER DIMINISHING IN THE MORNING...WITH
MOSTLY CLEAR/PARTLY CLOUDY SKIES IN THE AFTERNOON. MODELS REMAIN
IN GOOD AGREEMENT SHOWING WARMER TEMPS /5+ DEGREES/ ALOFT MOVING
INTO THE REGION...AND WINDS ARE EXPECTED TO CONTINUE FROM THE
SOUTH /PERHAPS A TOUCH OF A WRLY COMPONENT/...SATURDAY STILL
LOOKING TO BE THE WARMEST DAY OF THE NEXT SEVERAL. WITH MANY
LOCATIONS EXCEEDING EXPECTATIONS TODAY...DID TREND HIGHS UP A
BIT...NEAR THE MAV GUIDANCE...WHICH BRINGS WIDESPREAD MID
50S...AND READINGS NEAR 60 IN THE FAR S/SWRN PORTIONS OF THE AREA.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM CST FRI NOV 21 2014
CONTINUED DRY WEATHER IS EXPECTED THROUGH THE EXTENDED PERIODS WITH
TEMPERATURES FLUCTUATING NEAR OR JUST BELOW CLIMATOLOGY THROUGH
NEXT WEDNESDAY...FOLLOWED BY A BRIEF SHOT OF UNSEASONABLY COLD
AIR NEXT THURSDAY...WHICH WILL LIKELY HOLD DOWN HIGH TEMPERATURES
JUST BELOW FREEZING THANKSGIVING AFTERNOON.
LOOKING AT THE BIGGER PICTURE...AN UPPER LEVEL TROUGH CROSSING THE
NORTHERN ROCKIES SATURDAY NIGHT WILL STEER A COLD FRONT ACROSS THE
REGION ON SUNDAY...BRINGING GUSTY NORTHERLY WINDS AND COOLER
TEMPERATURES TO THE AREA TO FINISH OFF THE WEEKEND. WHILE THERE
WILL LIKELY BE SOME MOISTURE POOLING AHEAD OF THIS FRONT ACROSS
SOUTHEASTERN NEBRASKA AND PORTIONS OF KANSAS OVERNIGHT SATURDAY
THROUGH SUNDAY MORNING...OPTED TO KEEP THE FORECAST DRY AS THE NAM
WAS TOO AGGRESSIVE TRYING TO SQUEEZE OUT SOME LIGHT DRIZZLE THIS
MORNING ACROSS OUR LOCAL AREA...AND THINK THAT THIS IS ALSO THE
CASE FOR LATE SATURDAY NIGHT/EARLY SUNDAY MORNING...ESPECIALLY
SINCE THE AXIS OF THIS ACTIVITY IS EVEN FURTHER EAST THAN WHAT WAS
MODELED FOR TODAY. OTHERWISE...DO EXPECT AN INCREASE IN CLOUDS
FROM THE NORTHWEST SUNDAY MORNING WITH THE FRONT...WITH ANY POST
FRONTAL PRECIP EXPECTED TO REMAIN TO THE NORTH AND EAST OF THE
LOCAL AREA.
THE WARMEST DAY OF THE EXTENDED PERIODS IS EXPECTED TO BE SUNDAY
AFTERNOON...WHEN TEMPERATURES ARE EXPECTED TO CLIMB TO NEAR OR JUST
ABOVE CLIMATOLOGY. THEREAFTER...EXPECT PERSISTENT NORTHWESTERLY
FLOW TO CONTINUE ACROSS THE REGION THROUGH MID WEEK AS A RIDGE
OF HIGH PRESSURE STRENGTHENS ALONG THE WEST COAST...WITH THIS
GENERALLY COOL WEATHER PATTERN EXPECTED TO HOLD DOWN TEMPERATURES
IN THE MID 30S TO MID 40S ACROSS THE MUCH OF THE FORECAST AREA
THROUGH WEDNESDAY. AFTER THAT...TEMPERATURES ARE EXPECTED TO TAKE
A BRIEF PLUNGE ON THANKSGIVING DAY AS MODELS ARE KEYING IN ON A
REINFORCING SHOT OF COLD AIR WHICH WILL PLUNGE TEMPERATURES DOWN
10-15F FROM EARLIER IN THE WEEK. THANKFULLY...THE BRUNT OF THIS
COOLER AIRMASS WILL BE FOCUSED FURTHER EAST OF THE LOCAL
AREA...AND TEMPERATURES SHOULD MODERATE AFTER A DAY OR TWO...AS
THE RIDGE OF HIGH PRESSURE ACROSS THE WEST COAST BREAKS DOWN AND
MORE ZONAL FLOW BECOMES ESTABLISHED ALOFT. WHILE INITIALLY WE HAD
SOME SMALL CHANCES FOR SNOW WITH THIS SECONDARY SHOT OF COLD AIR
ON THANKSGIVING DAY...MODELS ARE NOW KEEPING THE AREA DRY AND
COMING INTO BETTER AGREEMENT...AND NO SIGNIFICANT CHANCE OF PRECIP
IS NOW ANTICIPATED THROUGH THE EXTENDED PERIODS.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1155 PM CST FRI NOV 21 2014
THE AVIATION FORECAST IS LOADED WITH CHALLENGES IN THE SHORT TERM
DUE TO A LOW STRATUS BANK THAT JUST PRIOR TO MIDNIGHT HAS BEEN
MEANDERING AROUND BETWEEN KGRI AND KEAR. KGRI IS SOCKED IN UNDER THE
LOW CLOUDS WHILE KEAR IS JUST WEST OF THE CLOUD SHIELD. THESE LOW
CLOUDS WILL CONTINUE TO MEANDER AROUND THE AREA TONIGHT AND THEN
SLIDE FURTHER EAST OF THE AREA...ESPECIALLY AFTER DAY BREAK. IN
ADDITION TO THE LOW CLOUDS...KGRI COULD ALSO SEE VISIBILITY
REDUCTIONS. THE WIND WILL NOT CHANGE MUCH AND WILL GENERALLY RANGE
FROM SOUTH TO SOUTHWEST THROUGH THE PERIOD.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HEINLEIN
SHORT TERM...ADP
LONG TERM...ROSSI
AVIATION...WESELY
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1100 PM CST FRI NOV 21 2014
.UPDATE...
ISSUED AT 1058 PM CST FRI NOV 21 2014
UPDATED THE FORECAST TONIGHT TO HIT THE FOG HEAVIER AND ADD A
LITTLE DRIZZLE TO MOST OF THE CWA. STRATUS HAS MADE IT FARTHER
NORTH THAN ORIGINALLY FORECAST. HRRR SEEMS TO HAVE A GOOD GRIP ON
THIS AND BEGINS TO MOVE THE STRATUS SOUTHEAST LATE TONIGHT BUT
HANGS ONTO IT IN OUR FAR SOUTHEAST INTO THE MORNING HOURS. THIS
WILL HOLD TEMPS UP DOWN THERE AND I HAVE RAISED LOWS. ANY
DRIZZLE/STRATUS WILL BE ABOVE FREEZING ACCORDING TO THE DEPENDABLE
HRRR AND I HAVE NO REASON TO DOUBT THIS...SO FREEZING DRIZZLE
SHOULD NOT BE A PROBLEM.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM CST FRI NOV 21 2014
HAVE SEEN QUIET CONDITIONS ACROSS THE CWA TODAY...WITH UPPER AIR
AND SATELLITE IMAGERY SHOWING A WEAK UPPER LEVEL DISTURBANCE
MAKING ITS WAY ACROSS THE REGION...WHILE A STRONGER LOW PRESSURE
SYSTEM SPINS OVER THE DESERT SW. AT THE SFC...THE CWA IS SET UP
BETWEEN HIGH PRESSURE CENTERED OVER THE ERN THIRD OF THE CONUS AND
A TROUGH OF LOW PRESSURE DRAPED THROUGH THE HIGH
PLAINS...RESULTING IN CONTINUED SRLY WINDS. VISIBLE SATELLITE
IMAGERY SHOWS A EXPANSIVE AREA OF LOW LEVEL STRATUS WHICH HAS BEEN
GRADUALLY MAKING ITS WAY NORTH THROUGH THE DAY...AND IN THE PAST
FEW HOURS HAS FINALLY MADE IT INTO THE SRN PORTIONS OF THE CWA.
THE LOWER LEVEL RH FIELDS OF THE RAP/NAM HAVE BEEN HANDLING ITS
PROGRESSION WELL TODAY. TEMPS HAVE WARMED A BIT MORE THAN EXPECTED
TODAY...3 PM OBS RANGE FROM THE LOWER 50S IN THE ODX/LXN/PHG
AREAS...MID TO UPPER 40S CENTRAL AND LOCATIONS EAST ALONG THE
STATE LINE...STILL SOME UPPER 30S IN THE NORTHEAST CORNER.
THROUGH THE OVERNIGHT HOURS TONIGHT INTO THE FIRST PART OF
SATURDAY MORNING...THE MAIN CONCERN IS GOING TO LIE WITH THIS
CLOUD COVER...AND FOG POTENTIAL. WILL STICK CLOSE TO THE NAM/RAP
FOR THE EVOLUTION OF THE LL STRATUS...WHICH KEEPS CREEPING IT
NORTH...THEN GIVES IT A SHOVE OFF TO THE EAST THROUGH THE EVENING
HOURS. EXPECTING LITTLE CHANGE WITH THE OVERALL SFC
PATTERN...WINDS REMAINING SRLY WITH SPEEDS ARND 10 MPH. MODELS
THIS MORNING STARTING SHOWING BETTER POTENTIAL FOR THE DEVELOPMENT
OF FOG...MAINLY ACROSS THE ERN HALF OF THE CWA...AREAS AFFECTED BY
STRATUS TODAY OR ON THE EDGE OF THE STRATUS TONIGHT. MET/MAV/LAV
NOT LENDING MUCH SUPPORT TO LOWER VISIBILITIES OR CEILINGS...BUT
DID INSERT A MENTION OF PATCHY AND AREAS OF FOG...MAINLY AFTER
MIDNIGHT. EVENING CREW WILL BE MONITORING TRENDS CLOSELY...AS
MODELS DEPICTED LOCATIONS OUTSIDE OF THE CWA BEING AFFECT
FIRST...WILL SEE HOW THINGS PLAY OUT.
FOR TOMORROW...OUTSIDE OF THE POSSIBILITY OF SOME LINGERING FOG IN
THE MORNING...DRY CONDITIONS ARE EXPECTED. THAT MAIN UPPER LEVEL
LOW PRESSURE SYSTEM SHIFTS OUT OF THE DESERT SW...BUT BY THE END
OF THE DAY STILL REMAINS WELL SOUTH OF THE CWA IN TX. AM BEING
OPTIMISTIC WITH THE CLOUD COVER DIMINISHING IN THE MORNING...WITH
MOSTLY CLEAR/PARTLY CLOUDY SKIES IN THE AFTERNOON. MODELS REMAIN
IN GOOD AGREEMENT SHOWING WARMER TEMPS /5+ DEGREES/ ALOFT MOVING
INTO THE REGION...AND WINDS ARE EXPECTED TO CONTINUE FROM THE
SOUTH /PERHAPS A TOUCH OF A WRLY COMPONENT/...SATURDAY STILL
LOOKING TO BE THE WARMEST DAY OF THE NEXT SEVERAL. WITH MANY
LOCATIONS EXCEEDING EXPECTATIONS TODAY...DID TREND HIGHS UP A
BIT...NEAR THE MAV GUIDANCE...WHICH BRINGS WIDESPREAD MID
50S...AND READINGS NEAR 60 IN THE FAR S/SWRN PORTIONS OF THE AREA.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM CST FRI NOV 21 2014
CONTINUED DRY WEATHER IS EXPECTED THROUGH THE EXTENDED PERIODS WITH
TEMPERATURES FLUCTUATING NEAR OR JUST BELOW CLIMATOLOGY THROUGH
NEXT WEDNESDAY...FOLLOWED BY A BRIEF SHOT OF UNSEASONABLY COLD
AIR NEXT THURSDAY...WHICH WILL LIKELY HOLD DOWN HIGH TEMPERATURES
JUST BELOW FREEZING THANKSGIVING AFTERNOON.
LOOKING AT THE BIGGER PICTURE...AN UPPER LEVEL TROUGH CROSSING THE
NORTHERN ROCKIES SATURDAY NIGHT WILL STEER A COLD FRONT ACROSS THE
REGION ON SUNDAY...BRINGING GUSTY NORTHERLY WINDS AND COOLER
TEMPERATURES TO THE AREA TO FINISH OFF THE WEEKEND. WHILE THERE
WILL LIKELY BE SOME MOISTURE POOLING AHEAD OF THIS FRONT ACROSS
SOUTHEASTERN NEBRASKA AND PORTIONS OF KANSAS OVERNIGHT SATURDAY
THROUGH SUNDAY MORNING...OPTED TO KEEP THE FORECAST DRY AS THE NAM
WAS TOO AGGRESSIVE TRYING TO SQUEEZE OUT SOME LIGHT DRIZZLE THIS
MORNING ACROSS OUR LOCAL AREA...AND THINK THAT THIS IS ALSO THE
CASE FOR LATE SATURDAY NIGHT/EARLY SUNDAY MORNING...ESPECIALLY
SINCE THE AXIS OF THIS ACTIVITY IS EVEN FURTHER EAST THAN WHAT WAS
MODELED FOR TODAY. OTHERWISE...DO EXPECT AN INCREASE IN CLOUDS
FROM THE NORTHWEST SUNDAY MORNING WITH THE FRONT...WITH ANY POST
FRONTAL PRECIP EXPECTED TO REMAIN TO THE NORTH AND EAST OF THE
LOCAL AREA.
THE WARMEST DAY OF THE EXTENDED PERIODS IS EXPECTED TO BE SUNDAY
AFTERNOON...WHEN TEMPERATURES ARE EXPECTED TO CLIMB TO NEAR OR JUST
ABOVE CLIMATOLOGY. THEREAFTER...EXPECT PERSISTENT NORTHWESTERLY
FLOW TO CONTINUE ACROSS THE REGION THROUGH MID WEEK AS A RIDGE
OF HIGH PRESSURE STRENGTHENS ALONG THE WEST COAST...WITH THIS
GENERALLY COOL WEATHER PATTERN EXPECTED TO HOLD DOWN TEMPERATURES
IN THE MID 30S TO MID 40S ACROSS THE MUCH OF THE FORECAST AREA
THROUGH WEDNESDAY. AFTER THAT...TEMPERATURES ARE EXPECTED TO TAKE
A BRIEF PLUNGE ON THANKSGIVING DAY AS MODELS ARE KEYING IN ON A
REINFORCING SHOT OF COLD AIR WHICH WILL PLUNGE TEMPERATURES DOWN
10-15F FROM EARLIER IN THE WEEK. THANKFULLY...THE BRUNT OF THIS
COOLER AIRMASS WILL BE FOCUSED FURTHER EAST OF THE LOCAL
AREA...AND TEMPERATURES SHOULD MODERATE AFTER A DAY OR TWO...AS
THE RIDGE OF HIGH PRESSURE ACROSS THE WEST COAST BREAKS DOWN AND
MORE ZONAL FLOW BECOMES ESTABLISHED ALOFT. WHILE INITIALLY WE HAD
SOME SMALL CHANCES FOR SNOW WITH THIS SECONDARY SHOT OF COLD AIR
ON THANKSGIVING DAY...MODELS ARE NOW KEEPING THE AREA DRY AND
COMING INTO BETTER AGREEMENT...AND NO SIGNIFICANT CHANCE OF PRECIP
IS NOW ANTICIPATED THROUGH THE EXTENDED PERIODS.
&&
.AVIATION...(FOR THE 00Z KGRI/KEAR TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 539 PM CST FRI NOV 21 2014
MVFR STATUS WILL BE ON THE BRINK OF REACHING THE
TERMINALS...ESPECIALLY GRI. NUMERICAL MODELS INDICATE THAT STRATUS
WILL STOP JUST SHORT OF THE TERMINALS...COMING UP FROM THE
SOUTH...AND THEN SHOVE OFF TO THE EAST LATE TONIGHT AND INTO
SATURDAY. WIND MAY START WITH AN EAST COMPONENT...BUT VEER SOUTH
TONIGHT...AND WILL STAY LIGHT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HEINLEIN
SHORT TERM...ADP
LONG TERM...ROSSI
AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS RALEIGH NC
300 AM EST SAT NOV 22 2014
.SYNOPSIS...HIGH PRESSURE REMAINS OVER THE REGION TODAY INTO
TONIGHT. A STRONG LOW PRESSURE MOVING FROM THE SOUTHERN PLAINS INTO
THE GREAT LAKES SUNDAY WILL SPREAD MOISTURE OVER THE REGION DURING
THE DAY ON SUNDAY. ANOTHER COLD FRONT WILL MOVE EAST ACROSS MUCH OF
THE AREA MONDAY...WITH LOW PRESSURE MOVING ALONG THE SOUTHEAST COAST
TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM SATURDAY...
THE LATEST SURFACE ANALYSIS SHOWED SURFACE HIGH PRESSURE OVER
CENTRAL NORTH CAROLINA...AND THE 00Z UPPER-AIR ANALYSIS NOTED VERY
DRY AIR AT 850MB WITH DEW POINT DEPRESSIONS WELL ABOVE 40C. THE
TEMPERATURE HAD FALLEN INTO THE UPPER TEENS AT LEAST AT KTDF...AND
WATCHING THE KRDU OVERNIGHT LOW SO FAR THE LOW WAS 25 AS OF THIS
WRITING. FOR TODAY...BUFR SOUNDINGS ARE CONTINUED DRY AND STABLE.
THE HRRR WRF FORECASTS NOTICEABLE HIGH CLOUDS TODAY...BUT OTHER
GUIDANCE SUCH AS THE CANADIAN CLOUD COVER MODEL...AND WHAT ONE WOULD
CONSIDER LOOKING AT THE UPPER-LEVEL RELATIVE HUMIDITY FORECASTS AND
BUFR SOUNDINGS...SUGGEST LESS. SATELLITE DATA UPSTREAM SUGGEST LESS
AS WELL...ALONG WITH THE JET LIFTING NORTH. UNDER EXPECTED SUNSHINE
HIGHS SHOULD BE 50 TO 55.
OVERNIGHT...CLOUDS SHOULD GRADUALLY INCREASE...BUT IT MAY BE A SLOW
INCREASE AS THE AIR MASS REMAINS DRY IN THE MEAN AT LEAST THROUGH
06Z MONDAY...AND MOISTURE ALOFT DOES NOT SHOW A STRONG INCREASE ON
BUFR SOUNDINGS UNTIL LATE TONIGHT. THE CANADIAN CLOUD COVER MODEL
ALSO SHOWS A SLOW AND GRADUAL INCREASE...AND EVEN A FEW AREAS OF
MOSTLY CLEAR TO PARTLY CLOUDY CONDITIONS ESPECIALLY NORTHEAST EVEN
LATE TONIGHT. OVERNIGHT LOWS WILL BE FORECAST ON THE COLD SIDE OF
GUIDANCE AND A FEW OF THESE LOWS MAY EVEN BE TOO HIGH IF LESS CLOUDS
OCCUR FOR LONGER PERIODS IN THE OVERNIGHT. UNDER THE WESTWARD
EXTENSION OF THE RIDGE...WINDS SHOULD BE LIGHT FOR MUCH OF THE NIGHT.
WILL KEEP A DRY FORECAST AS BOTH THE GFS AND NAM SEEM TO BE A LITTLE
SLOWER WITH THE APPROACH OF DEEPER MOISTURE. BY 12Z SUNDAY...THE NAM
IS FAIRLY MOIST ALOFT...BUT THE SUB-CLOUD LAYER REMAINS VERY DRY.
THE 850MB THETA-E GRADIENT IS JUST BEGINNING TO APPROACH CENTRAL
NORTH CAROLINA ON BOTH THE NAM AND GFS AT 12Z SUNDAY...AND THOSE
MODELS ARE ALSO SUBSIDENT AT THAT LAYER AT THAT TIME. DESPITE THE
DRY SUB-CLOUD LAYER...IF ANY PRECIPITATION WOULD OCCUR OVER THE FAR
SOUTHWEST PIEDMONT...FOR EXAMPLE...SUFFICIENT WARMING ALOFT PUSHES
THICKNESSES WELL INTO THE LIQUID CATEGORY...AND SURFACE WET BULB
TEMPERATURES ARE ABOVE FREEZING. IF ANYTHING DOES OCCUR...IT WOULD
BE VERY CLOSE TO 12Z SUNDAY AND THEN ALMOST CERTAINLY IN THE FORM OF
SPRINKLES.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...
THE NAM AND THE GFS ARE SLOW TO BRING IN GOOD LIFT TO CENTRAL NORTH
CAROLINA SUNDAY. HOWEVER...NUMEROUS PARAMETERS...INCLUDING 850MB
THETA-E...K INDICES...GENERAL 850MB LIFT...700MB VORTICITY...AMONG
OTHERS SUGGEST THAT PRECIPITATION WILL MOVE IN FROM THE SOUTHWEST
WITH THE GREATEST LIKELIHOOD OF RAIN IN CENTRAL NORTH CAROLINA FROM
ABOUT 18Z TO 05Z. HAVE CONFINED THE HIGHEST CHANCES IN THE GRIDDED
FORECAST FROM 20Z TO 04Z...AND SOME OF THE WRF GUIDANCE IS EVEN
SLOWER THAN THAT WITH THE ONSET PARTICULARLY FROM THE TRIANGLE NORTH
AND EAST. FUTURE FORECASTS MAY END UP TRENDING A LITTLE SLOWER...BUT
FOR PLANNING PURPOSES ANTICIPATE HIGH PROBABILITIES OF RAIN DURING
THE AFOREMENTIONED WINDOW.
CLOUDS SHOULD INCREASE...THOUGH THE UNCERTAINTY WITH THE ONSET OF
RAIN MAKES THE TEMPERATURE FORECAST CHALLENGING. EXCEPT IN THE
TRIAD...GUIDANCE HIGHS ARE RELATIVELY CLOSE...AND WILL PLAN TO GO
BETWEEN THERE. IF RAIN WOULD MOVE IN EARLIER...WOULD ALMOST
CERTAINLY LEAN TOWARD THE COOLER NAM BUT WITH SOME WRF GUIDANCE VOID
OF MUCH PRECIPITATION EVEN TO 18Z SUNDAY THINK AT LEAST A BLEND IS
WISE. IN TERMS OF THUNDER...BUFR SOUNDINGS PROVIDE FOR GREATEST
LAPSE RATES VERY LATE SUNDAY AFTERNOON THROUGH THE EVENING IN
ADVANCE OF A DRY SLOT WHICH BOTH THE NAM AND GFS BUFR SOUNDINGS
FORECAST MOVING IN FROM THE SOUTHWEST DURING THE NIGHT WITH
INCREASING 850MB SUBSIDENCE. 1000-500MB MUCAPE ON THE GFS IS LESS
THAN 200J/KG AND THE SHERBS3 IS LESS THAN ONE...BUT THE NAM IS
NOTICEABLY MORE UNSTABLE...ALTHOUGH IT IS DIFFICULT TO SEE SURFACE-
BASED CONCERNS ON THE NAM BUFR SOUNDINGS WITH A SLIGHT INVERSION
JUST OFF OF THE SURFACE. 0-3KM SHEAR AND HELICITY...AS EXPECTED...
ARE VERY HIGH AS WINDS JUST OFF OF THE SURFACE INCREASE GREATLY.
ADDED A SLIGHT CHANCE OF THUNDER DURING SUNDAY EVENING TO THE
FORECAST FOR THE INTERSTATE 95 CORRIDOR AS AT LEAST THERE IS A
SLIGHT CHANCE OF AT LEAST ELEVATED THUNDER...AND FOR THE HWO WILL
LIKELY ADD A MENTION OF AT LEAST WIND GUSTS TO 40MPH OR A LITTLE
HIGHER AS EVEN SHOWERS IN A RAPIDLY TIGHTENING SURFACE GRADIENT...
WITH 925MB WINDS APPROACHING 50KT...SHOULD RESULT IN A FEW QUITE
NOTICEABLE WIND GUSTS SIMPLY WITH PRECIPITATION. SPC HAS NOTED A
SLIGHT RISK OF SEVERE WEATHER WHERE THUNDER WILL BE ADDED TO THE
FORECAST AND WILL CERTAINLY NEED TO BE WATCHFUL OF INSTABILITY
TRENDS IN LATER FORECASTS...AS OTHER PARAMETERS ARE PLENTY HIGH
ENOUGH FOR ISOLATED SEVERE WEATHER. OVERNIGHT LOWS SUNDAY NIGHT NOT
MUCH DIFFERENT FROM THE HIGHS SUNDAY...STEADY TO RISING IN THE TRIAD
AND MAYBE A DIFFERENCE OF A DEGREE OR TWO ELSEWHERE IN GENERAL. -DJF
MONDAY AND MONDAY NIGHT...MID-LEVEL DRY AIR INTRUSION AND SUBSIDENCE
IN THE WAKE OF THE EXITING SHORTWAVE LIFTING OFF TO THE NORTH WILL
RESULT IN MOSTLY DRY CONDITIONS DURING THE DAY ON MONDAY. THE
TRAILING COLD FRONT WILL TRAVERSE THE AREA MONDAY EVENING/NIGHT BUT
AIRMASS IS JUST TOO DRY WITH LITTLE TO NO FORCING/LIFT ALOFT TO
SUPPORT POPS. TEMPERATURES MONDAY AFTERNOON IN THE PRE-FRONTAL WARM
SECTOR WILL WARM INTO THE UPPER 60S/NEAR 70 NW TO MID 70S SE. LOWS
MONDAY NIGHT WILL RANGE FROM LOWER 40S NW TO LOWER 50S SE AS CAA
SPREADS WEST TO EAST. -CBL
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 300 AM SATURDAY...
TUESDAY THROUGH WEDNESDAY: SOUTHERN STREAM TROUGH EMBEDDED AT THE
BASE OF THE AMPLIFYING LONG WAVE TROUGH WILL TRAVERSE THE GULF COAST
REGION ON TUESDAY AND THEN ACROSS THE SOUTHEAST ON WEDNESDAY. AFTER
A DRY START TO THE DAY ON TUESDAY...RAIN CHANCES WILL RETURN TUESDAY
EVENING/NIGHT AND INTO THE DAY ON WEDNESDAY AS WESTERN EDGE OF
DEEPER MOISTURE AXIS ATTENDANT TO OFFSHORE FRONTAL ZONE RETREATS
INLAND IN RESPONSE TO STRONG DPVA AND UPPER LEVEL DIVERGENCE WITHIN
THE RIGHT ENTRANCE REGION OF A 140-150KT JETSTREAK. BOTH THE GFS AND
EC CONTINUE TO TREND WETTER DURING THIS PERIOD WITH THE POTENTIAL
FOR CENTRAL AND EASTERN PORTIONS OF THE STATE TO RECEIVE SIGNIFICANT
RAINFALL. AS SUCH... WILL RAISE POPS TO CHANCE IN THE WEST TO LIKELY
IN THE EAST. NO P-TYPE ISSUES HERE WITH JUST A COLD RAIN FOR CENTRAL
NC. LOWS TUESDAY NIGHT IN THE MID/UPPER 30 NW TO LOWER 40S SE. HIGHS
WEDNESDAY IN THE 40S. PRECIP AND CLOUDS PULL OUT WEDNESDAY
EVENING/NIGHT WITH LOWS BACK DOWN INTO THE 30S.
THURSDAY AND FRIDAY: UNCERTAINTY REMAINS HIGH REGARDING THE APPROACH
OF THE NEXT BATCH OF SHORTWAVE ENERGY ROTATING EASTWARD WITHIN THE
BASE OF THE LONGWAVE TROUGH...WITH SOME GUIDANCE SUGGESTING A MID-
LEVEL SHORT WAVE MAY TRY TO CLOSE OFF OVER THE MID-ATLANTIC OR
CAROLINAS. ITS WORTH NOTING THAT NORTHERN STREAM SYSTEMS LIKE THIS
ARE OFTEN MOISTURE-STARVED... ESPECIALLY EAST OF THE MOUNTAINS.
GIVEN THERE HAS BEEN LITTLE CONTINUITY AMONG THE DETERMINISTIC
GUIDANCE ALONG WITH LARGE SPREAD AMONG THE ENSEMBLE MEMBERS...WILL
PLAY THE CONSERVATIVE APPROACH AND MAINTAIN A DRY FORECAST FOR
THURSDAY AND FRIDAY. IT LOOKS ALMOST CERTAIN HOWEVER THAT THIS
SYSTEM WILL DELIVER ANOTHER SHOT OF COLD ARCTIC AIR INTO THE
SOUTHEAST BY THE LATE WEEK AND INTO NEXT WEEKEND.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 1250 AM SATURDAY...
FOR THE 06Z VALID TAF PERIOD...VFR CONDITIONS CONTINUE. LIGHT WINDS
THIS MORNING GRADUALLY VEER WITH A SLIGHT INCREASE IN WIND SPEEDS
AFTER SUNRISE...WITH SUSTAINED VALUES EXPECTED TO BE UNDER 10KT.
SURFACE WINDS UNDER HIGH PRESSURE BECOME LIGHT OR CALM AGAIN THIS
EVENING BACKING SLIGHTLY.
BEYOND THE 06Z VALID TAF PERIOD...CONDITIONS DETERIORATE SUNDAY AND
AS AREAS OF RAIN MOVE IN TO CENTRAL NORTH CAROLINA NUMEROUS AREAS OF
SUB-VFR...LIKELY IFR...CONDITIONS DEVELOP DURING THE DAY CONTINUING
AT LEAST INTO SUNDAY EVENING. WINDS OFF OF THE SURFACE WILL ALSO
INCREASE SUNDAY AND REACH OR EVEN EXCEED 50KT BY 2000FT WHICH COULD
MAKE LOW-LEVEL WIND SHEAR A PROBLEM BY LATE IN THE DAY INTO THE
OVERNIGHT HOURS. IMPROVING AVIATION CONDITIONS ARE POSSIBLE MONDAY
AND WHILE SOUTHWEST WINDS OFF THE SURFACE WILL NOT BE AS STRONG...A
GUSTY CHARACTER TO THE SURFACE WINDS CONTINUES. AS LOW PRESSURE
MOVES ALONG THE SOUTHEAST COAST TUESDAY INTO WEDNESDAY...UNCERTAINTY
INCREASES IN TERMS OF THE POTENTIAL FOR A RETURN TO A PERIOD OF SUB-
VFR CONDITIONS AND PRECIPITATION...ESPECIALLY EAST OF THE TRIAD. THE
NAM MODEL RETURNS THESE CONDITIONS MUCH FASTER TUESDAY...WHILE THE
GFS AND ECMWF ARE SLOWER...MORE OVERNIGHT TUESDAY INTO WEDNESDAY.
THE CURRENT THINKING IS TOWARD THE SLOWER SOLUTIONS.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF
SHORT TERM...DJF/CBL
LONG TERM...CBL
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1153 PM CST FRI NOV 21 2014
.UPDATE...
ISSUED AT 1153 PM CST FRI NOV 21 2014
MADE SOME FURTHER TWEAKS TO CLOUDS AS MOST OF THE STRATUS MOVING
INTO THE NORTH HAS NOT HAD A HUGE SOUTHWARD PUSH AS OF YET. TEMPS
HAVE STAYED MILD AND SOME SPOTS ARE EVEN SEEING SOME DOWNSLOPE
WARMING. THIS INFLUENCE SHOULD WANE AS WINDS LIGHTEN.
UPDATE ISSUED AT 956 PM CST FRI NOV 21 2014
ADJUSTED CLOUD COVER A BIT FOR TIMING OF STRATUS COMING DOWN OUT
OF CANADA. MODEL SOUNDINGS FOR OUR NORTHEASTERN COUNTIES SHOW SOME
FAVORABLY FOR FREEZING DRIZZLE WITH A LOW LEVEL SATURATED LAYER
AND DRY AIR ALOFT. ON THE OTHER HAND...NOT MUCH RISING MOTION IN
SAID SATURATED LAYER AND LOOKING AT THE CLOUD LEVELS OBSERVED
UPSTREAM IN CANADA MOST ARE ABOVE 1000 FT. WOULD LIKE TO HAVE SOME
CLOSER DEW POINT DEPRESSIONS AND LOWER CEILINGS FOR DRIZZLE
FORMATION SO WILL KEEP MENTION OUT FOR NOW. WILL KEEP THE PATCHY
FOG MENTION IN THE NORTHWEST HOWEVER AS WINDS BEGIN TO GO LIGHT
AHEAD OF THE CLOUDS COMING IN AND THERE COULD BE SOME RADIATING
OUT A JUST SOME PATCHES OF FOG IN AREAS WHERE THERE WAS SNOW MELT
TODAY. ADJUSTED TEMPS UP A BIT AS MANY LOCATIONS HAVE BEEN STAYING
IN THE UPPER 20S TO 30S. THINK THERE WILL BE SOME FALLING BUT WITH
A FAIRLY WARM AIR MASS AND CLOUDS COMING IN LOWS WILL STAY IN THE
20S OVERNIGHT.
UPDATE ISSUED AT 644 PM CST FRI NOV 21 2014
WINDS WILL CONTINUE TO DIMINISH MAINLY IN THE NORTHWESTERN
COUNTIES WHERE THE TROUGH AXIS WILL ARRIVE LATER TONIGHT. WITH
LIGHT WINDS AND SOME DECENT RADIATING OUT...THINK SOME PATCHY FOG
IN SOME AREAS IS POSSIBLE. RAP HAS SOME LOW VIS IN THE NORTHWEST
SO KEPT A MENTION FOR THE DEVILS LAKE BASIN INTO THE NORTHERN RED
RIVER VALLEY.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 323 PM CST FRI NOV 21 2014
SYSTEM TRACKING ACROSS SOUTHERN CANADA WILL CONTINUE EASTWARD
OVERNIGHT...RESULTING IN A WEAK COLD FRONT TO NEAR THE
INTERNATIONAL BORDER (MAIN RESULT WILL BE INCREASED CLOUD COVER).
THIS FEATURE WILL QUICKLY BE WASHED OUT AS THE NEXT SYSTEM
APPROACHES AND SOUTHERLY RETURN FLOW AGAIN DEVELOPS ON SATURDAY.
TEMPERATURES WILL BE THE MAIN CHALLENGE...WITH SATURDAY MAX TEMPS
SIMILAR OR EVEN SLIGHTLY WARMER (ESPECIALLY ACROSS THE SOUTHERN
FA) THAN TODAYS...BUT NOT SURE HOW MUCH WARMER.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 323 PM CST FRI NOV 21 2014
SATURDAY NIGHT-MONDAY...CONFIDENCE REMAINS LOW DURING THIS PERIOD
REGARDING HOW THE UPPER LOW WILL EVOLVE. MODELS ALL AGREE THAT THE
SOUTHERN SYSTEM WILL BE WELL EAST OF THE REGION...BUT COULD STILL
ACT TO SLOW DOWN THE NORTHERN WAVE THAT WILL AFFECT THIS REGION.
THE GFS IS SLIGHTLY QUICKER SATURDAY NIGHT AND INDICATES A BAND OF
PRECIP ASSOCIATED WITH 700MB CONVERGENCE/DEFORMATION. IF PRECIP
DOES OCCUR...IT COULD BE FREEZING RAIN/SLEET GIVEN THE WARM
TEMPERATURES ALOFT. DID INCLUDE A SCHC FOR MIXED PRECIP...BUT WITH
OTHER MODELS DRY (SLOWER) CANNOT GO WITH HIGHER POPS. THE UPPER
LOW THEN MOVES ACROSS THE REGION LATER SUNDAY INTO MONDAY. AS
THIS OCCURS...ANTICIPATE STRONG N/NW WINDS ALONG WITH SNOW
SHOWERS. AS OF NOW...WINDS ALONG AND WEST OF THE VALLEY SHOULD BE
30-40 MPH WITH HIGHER GUSTS (GIVEN EXPECTED COLD AIR
ADVECTION...SFC PRESSURE GRADIENT...AND WIND SPEEDS ALOFT). THESE
WINDS COMBINED WITH SNOW SHOWERS WOULD RESULT IN BRIEF PERIODS OF
SIGNIFICANTLY REDUCED VISIBILITY. ANY SNOW-PACK CURRENTLY ON THE
GROUND WILL NOT BE BLOW-ABLE WITH TEMPERATURES ABOVE FREEZING
DURING THE DAY TODAY...SATURDAY...AND POSSIBLY SUNDAY. SO...HOW
MUCH SNOW ACTUALLY FALLS WILL DETERMINE HOW WIDESPREAD THE BLOWING
SNOW IS DURING THIS PERIOD. STRONGEST FORCING WILL BE NORTH OF THE
INTERNATIONAL BORDER...AND GIVEN THE EXPECTED FORCING OVER THIS
REGION THINKING 1-2 INCHES AT MOST SOUTH OF THE INTERNATIONAL
BORDER (ALTHOUGH GFS INDICATES A STRONGER SYSTEM AND HIGHER QPF).
WILL CONTINUE TO MONITOR...BUT THE CURRENT MENTION IN THE HWO AND
WEATHER STORY SEEMS LIKE THE APPROPRIATE PRODUCTS AT THIS MOMENT
IN TIME.
MONDAY NIGHT-FRIDAY...500 MB TROUGH OVER THE GREAT LAKES REGION
MONDAY NIGHT INTO THURSDAY WITH FCST AREA ON THE COLD SIDE. CLOUDS
AND A CHANCE FOR SOME LIGHT SNOW WILL OCCUR TUESDAY INTO TUESDAY
NIGHT AHEAD OF A WEAK UPPER DISTURBANCE WHICH WILL MOVE THROUGH.
COLDEST AIRMASS AND HIGH PRESSURE SYSTEM TO ARRIVE WEDNESDAY-
THURSDAY. MODERATION OCCURS FRIDAY BUT LONG RANGE MODELS KEEP AREA
NEAR THE TIGHT BAROCLINIC ZONE BETWEEN COLD NORTH AND WARMER
SOUTHWEST. 12Z GFS/ECMWF SEEM IN GOOD AGREEMENT AND BLENDS WELL
WITH BLENDED MODEL DATA PROCEDURE. GOOD NEWS IS NO SIGNIFICANT
STORM SYSTEM FOR THE THANKSGIVING DAY TRAVEL PERIOD LOCALLY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1153 PM CST FRI NOV 21 2014
STRATUS HAS STARTED TO CROSS THE CANADIAN BORDER BUT HAS STAYED
NORTH OF THE TAF SITES SO FAR. THE MODELS HAVE BEEN KEEPING THE
FRONTAL BOUNDARY AND LOWER CIGS FURTHER NORTH THAN PREVIOUS
RUNS...STAYING NORTH OF KGFK AND KBJI. THINK THAT THE MVFR STRATUS
MAY SEEP INTO KDVL AND KTVF FOR A WHILE THIS MORNING...BUT SHOULD
GO BACK TO VFR FOR A WHILE AS THE FRONT WASHES OUT SATURDAY
AFTERNOON. MORE MOISTURE COMING IN LATE IN THE PERIOD SHOULD BRING
CIGS BACK DOWN TO MVFR.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...TG
LONG TERM...TG/RIDDLE
AVIATION...JR
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
458 AM EST SAT NOV 22 2014
.SYNOPSIS...
FLOW BECOMES SOUTHWESTERLY TODAY...INCREASING SUNDAY FOR A WARMER
BUT WET WEEKEND. LOW PRESSURE BRINGS A WARM FRONT SUNDAY NIGHT...
FOLLOWED BY A COLD FRONT MONDAY WITH GOOD CHANCES FOR RAIN SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
LATEST RADAR TRENDS HAVE A SLUG OF MOISTURE MOVING TOWARDS WV AND
TEMPS ARE STILL IN THE MID TEENS. HRRR HAS THE SLUG DRYING OUT
EXCEPT FOR PORTIONS OF SE OHIO...SO WENT WITH A FREEZING RAIN
ADVISORY FOR A BRIEF PERIOD WHERE PRECIP WILL BE FALLING INTO A
COLD AIR MASS. OBSERVATION IN PERRY COUNTY AT 27 SO OPTED TO LEAVE
THEM OUT AS THE WARM AIR EXTENDS TO ABOUT PERRY CNTY. AFTER 9 AM
TEMPS SHOULD WARM ABOVE FREEZING AND THE FZRA THREAT WILL BE
GONE.
THEN A PLEASANT DRY...DAY WHERE TEMPERATURES REBOUND TO NORMAL.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
AN APPROACHING LOW PRESSURE SYSTEM WILL LIFT FROM THE MISSISSIPPI
VALLEY...NORTH NORTHEAST INTO THE OH VALLEY AND WV SUNDAY AND
MONDAY. MODELS INDICATE WIND FLOW WILL TURN DEEP FROM THE SOUTH
SOUTHWEST...TO BRING MOIST AND WARM AIR MASS ON SUNDAY. A WARM
FRONT WILL MERGE FROM THIS FLOW TO PRODUCE AREAS OF RAIN SPREADING
FROM SOUTH TO NORTH.
WIND FLOW WILL INCREASE BY 00Z MONDAY...AS SUGGESTED BY H850 WINDS
FROM THE GFS/ECMWF OF ABOUT 65-70 KNOTS. UNDER ISENTROPIC
UP GLIDING...IT WILL BE MORE LIKELY FOR SOME OF THESE WINDS TO
CREATE GUSTY CONDITIONS OVER HIGHER ELEVATIONS.
AN ASSOCIATED COLD FRONT WILL CROSS WEST TO EAST EARLY MONDAY. WITH H850
TEMPERATURES AROUND 10C...EXPECT ALL PCPN TO FALL AS LIQUID.
THEREFORE...EXPECT ROUNDS OF SCATTERED TO NUMEROUS RAIN SHOWERS.
PW AROUND 1.25 INCHES AND STRONG DEEP LAYERED SHEAR COULD PRODUCE
A LOW CHANCE FOR THUNDER...BUT WILL KEEP MENTION OUT OF FORECAST.
COLDER AIR RUSHES IN BEHIND THE COLD FRONT DROPPING TO MINUS 6C BY
06 TUESDAY.
WENT CLOSE TO PREVIOUS TEMPERATURES...PERHAPS A LITTLE WARMER
SUNDAY INTO MONDAY DUE TO STRONG DEEP SOUTH SOUTHWESTERLY FLOW.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
SHOWERS WILL BEGIN TO END ON MONDAY NIGHT AS THE TROUGH WEAKENS AND
MOVES EAST. MODEL TRENDS HAVE WAFFLED A BIT WITH NEITHER THE GFS
AND ECMWF STAYING WITH A GREAT SOLUTION. SHORTWAVES ARE MORE
EVIDENT IN DEEPER TROUGH EXHIBITED BY THE ECMWF...BUT THE GFS
CURRENTLY SHOWS A MORE WESTERN FLOW. TOOK A BLEND OF THE TWO MODELS
TO RESOLVE SOME OF THE DISAGREEMENT IN THE HOPES THE SOLUTIONS WILL
CONVERGE AS WE MOVE CLOSER IN TIME.
TEMPERATURES WILL COOL SIGNIFICANTLY BY TUESDAY WITH THE PASSAGE OF
A COLD FRONT. THESE COOLER TEMPERATURES COMBINED WITH LOW PRESSURE
MOVING EAST FROM THE GREAT LAKES WILL PROVIDE SOME OPPORTUNITY FOR
SOME SNOW SHOWERS ALONG THE OHIO RIVER EARLY
THURSDAY...TRANSITIONING TO RAIN BY AFTERNOON FOR THE LOWLANDS. THE
MOUNTAINS WILL CONTINUE TO HAVE A SLIGHT CHANCE OF SOME SNOW SHOWERS
THROUGH THE NIGHT.
&&
.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
QUIET VFR WEATHER. A BRIEF PERIOD OF FREEZING RAIN IS POSSIBLE IN
INTERIOR SE OHIO SAT MORNING.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SUNDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: LOW CHANCE OF MVFR CIGS ACROSS INTERIOR SE OHIO
SAT MORNING AND THE NRN WV MOUNTAINS SAT MIDDAY AND AFTERNOON.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SAT 11/22/14
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EST 1HRLY 03 04 05 06 07 08 09 10 11 12 13 14
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z SUNDAY...
IFR POSSIBLE ON EASTERN MOUNTAIN SLOPES AND ACROSS THE MIDDLE OHIO
VALLEY IN RAIN AND STRATUS LATE SUN INTO MON MORNING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR WVZ009.
OH...FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR OHZ067-
075-076-083>086.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/JW
NEAR TERM...JW
SHORT TERM...ARJ
LONG TERM...LS
AVIATION...JW
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1053 PM CST FRI NOV 21 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 400 PM CST FRI NOV 21 2014
DIFFICULT LOW CONFIDENCE FORECAST IN THE NEAR TERM. TEMPERATURES
HAVE FINALLY RISEN ABOVE FREEZING IN MOST LOCATIONS ACROSS THE AREA.
THIS HAS PROMOTED AT LEAST A LITTLE BIT OF SNOW MELT. AREA OF
STRATUS THAT HAS BEEN CONTAINED ACROSS MISSOURI AND KANSAS IS NOW
CREEPING NORTHWARD...AND COULD IMPACT PORTIONS OF NORTHWEST IOWA
MAINLY EAST OF THE TAF SITES. ON THE BACK EDGE OF THE STRATUS...
HRRR...RAP AND SREF SUGGEST FOG WILL DEVELOP AFTER 06Z. TRIED TO
KEEP MENTION OF FOG SOUTH OF THE BUFFALO RIDGE WITH STRONG WINDS
LINGERING IN ELEVATED LOCATIONS. KEPT LOWS MILD NORTH OF THE BUFFALO
RIDGE WITH DOWNSLOPE EFFECT. ACROSS THE REST OF THE AREA...SIDED
FAIRLY CLOSE TO CONSENSUS.
STRONG WARMING ALOFT IS EXPECTED THROUGHOUT THE DAY ON
SATURDAY...THE QUESTION REMAINS THOUGH AS TO HOW MUCH OF THAT
WARMING WILL SURFACE. 925 HPA TEMPS WARM THROUGHOUT THE
DAY...STARTING NEAR 3 TO 5 C AND WARMING TO 5 TO 7C BY 00Z SUNDAY.
FOG AND/OR STRATUS MAY LINGER THROUGH THE MORNING HOURS...LIMITING
THE POTENTIAL TO WARM. WHERE THERE IS A VOID OF LOW CLOUDS...SHOULD
SEE SOME NICE WARMING WITH SOUTHWEST FLOW ACROSS THE AREA. STILL
WILL BE FAR FROM FULL MIXOUT...BUT LOOKS TO BE A RELATIVELY MILD DAY
WITH TEMPERATURES ABOVE NORMAL. EXPECT SNOW PACK TO CONTINUE TO
DWINDLE.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 400 PM CST FRI NOV 21 2014
CLOUDS BUILD BACK INTO THE AREA SATURDAY EVENING AND NIGHT AHEAD OF
THE NEXT STORM SYSTEM EXPECTED TO IMPACT THE REGION SUNDAY THROUGH
MONDAY EVENING. SPLIT FLOW WILL KEEP THE AREA LARGELY DRY INTO
SUNDAY AFTERNOON AS THE SOUTHERN STREAM LIFTS A TROUGH NORTHWARD
FROM THE SOUTHERN PLAINS INTO THE MID MISSISSIPPI VALLEY ON SUNDAY
WHILE A TROUGH DIGS INTO THE NORTHERN HIGH PLAINS ALONG THE NORTHERN
STREAM. WITH THE FORECAST AREA STATIONED BETWEEN THESE TWO
AREAS...DRIER CONDITIONS WILL PREVAIL UNDER SOME MID TO HIGH CLOUDS.
A LITTLE LIGHT RAIN POSSIBLY MIXED WITH SOME NORTH IN THE NORTHEAST
MAY CREEP INTO OUR FAR EASTERN BORDER DURING THE DAY. IT LOOKS LIKE
THE BEST SUPPORT FOR ANY WET WEATHER WILL REMAIN EAST OF OF THE
FORECAST AREA. WITH SOMEWHAT BREEZY SOUTHWEST WINDS AND WARMER AIR
ALOFT SATURDAY NIGHT...TEMPERATURES WILL STAY MILD OVERNIGHT WITH
LOWS IN THE 30S. SUNDAY WILL REMAIN MILD AS WINDS TURN NORTHWESTERLY
AND BECOME WINDY BY AFTERNOON. TEMPERATURES WARM INTO THE MID 30S TO
MID 40S BEFORE THE COLD AIR BEGINS LEAKING BACK INTO THE REGION
SUNDAY NIGHT INTO MONDAY.
WITH THE NORTHERN STREAM WAVE SLIDING ACROSS THE NORTHERN PLAINS
SUNDAY EVENING THROUGH MONDAY...SOME LIGHT SNOW WILL SPREAD EAST
ACROSS THE AREA. MOISTURE DOES NOT LOOK TOO IMPRESSIVE WITH THIS
WAVE...HOWEVER SOME DECENT FRONTOGENESIS AND MODEST QG FORCING
SLIDING THROUGH THE AREA WILL ALLOW FOR SOME ISOLATED TO SCATTERED
LIGHT TO FALL. MOST AREAS WILL SEE LESS THAN HALF INCH...BUT COULD
BE A LITTLE HIGHER IN PARTS OF SOUTHWEST MINNESOTA. WITH BLUSTERY
WINDS...ANY SNOW THAT DOES FALL WILL BLOW AROUND...BUT ANY EXISTING
SNOW PACK SHOULD HAVE ENOUGH OF A CRUST TO NOT CAUSE ANY BLOWING
SNOW ISSUES.
MODELS SHOWING BETTER AGREEMENT HEADING INTO THE MIDDLE OF NEXT
WEEK. LEFT A LOW CHANCE FOR LIGHT SNOW MAINLY ACROSS OUR NORTHERN
HALF ON TUESDAY NIGHT AS ANOTHER FRONT DROPS THROUGH THE REGION. DRY
AND COLD WEATHER PERSISTS WEDNESDAY AND THURSDAY...WITH HIGHS
COOLING FURTHER INTO THE MID TEENS TO MID 20S. SHARP RIDGING OVER
THE INTERMOUNTAIN WEST EASES INTO THE PLAINS AND FLATTENS OUT...BUT
TEMPERATURES LOOK MUCH MILDER ON FRIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY EVENING)
ISSUED AT 1052 PM CST FRI NOV 21 2014
FORECAST CONTINUES TO REMAIN A CHALLENGE TONIGHT INTO TOMORROW.
PRETTY CONFIDENT KHON REMAINS VFR...BUT STRATUS AND FOG CONCERNS
REMAIN EAST OF THE JAMES RIVER. WATCHING LARGE AREA OF LOW STRATUS
CONTINUE TO PUSH NORTH TOWARDS THE REGION...WITH MVFR CIGS INTO
KSUX. BASED ON MODEL SOUNDINGS AND UPSTREAM OBS...THINK THEY WILL
EVENTUALLY GET CIGS BELOW 500 FEET...AND COULD POSSIBLY ALSO SEE
DENSE FOG. LESS CERTAIN ABOUT KFSD...WHICH WILL LIKELY BE NEAR THE
WEST EDGE OF ANY STRATUS AND FOG. BASED ON THE LATEST RAP AND HRRR
WILL KEEP IFR CIGS INTO KFSD LATER TONIGHT...ALTHOUGH AGAIN
CONFIDENCE IS LOW. WHAT IS ALSO UNCERTAIN IS HOW QUICKLY THE STRATUS
AND FOG EXITS TOMORROW. STAYED ON THE OPTIMISTIC SIDE FOR NOW GIVEN
LOW CONFIDENCE...BUT WOULD NOT BE SURPRISED IF LOW CIGS AND VIS
STICK AROUND LONGER THAN CURRENTLY FORECAST...AS WINDS WILL STAY OUT
OF THE SOUTH SOUTHEAST THROUGH THE DAY.
SO IN SUMMARY...AT THE LEAST THINK NORTHWEST IOWA AND PORTIONS OF
SOUTHWEST MINNESOTA WILL SEE LOW STRATUS AND POTENTIALLY DENSE FOG
TONIGHT INTO EARLY TOMORROW. THIS COULD EXTEND AS FAR WEST AS THE
INTERSTATE 29 CORRIDOR. FOR NOW HAVE IMPROVEMENTS BY MID
MORNING...BUT THE POSSIBILITY IS DEFINITELY THERE THAT THESE
CONDITIONS LINGER INTO LATE MORNING OR EVEN EARLY AFTERNOON...WITH
CONDITIONS SLOWLY IMPROVING TO VFR FROM WEST TO EAST.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...
LONG TERM...
AVIATION...CHENARD
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
214 AM CST SAT NOV 22 2014
.SHORT TERM...
MAIN FOCUS FOR THE SHORT TERM PERIOD CONTINUES TO BE THE UA LOW
DIGGING ESE ACROSS NWRN OLD MEXICO EARLY THIS MORNING...WHICH WILL
AID TO INCREASE PRECIP CHANCES LATER THIS MORNING.
AN AREA OF STRATUS AND FOGGY CONDITIONS ONCE AGAIN DEVELOPED ACROSS
ERN TEXAS AND OKLAHOMA PER 08Z METARS...THUS COINCIDING WITH THE
BEST SFC MOISTURE /DEWPOINTS IN THE 50S AND 60S/. LOW CLOUDS AND FOG
HAVE IMPACTED THE FAR SERN TX PANHANDLE...WHICH IS NOT SURPRISING
GIVEN A LOW TEMP-DEWPOINT SPREAD. THE HRRR SOLUTION HANDLED THE
EVOLUTION OF THE LOW CLOUDS AND FOG QUITE WELL YESTERDAY...AND SINCE
IT SHOWS A CONTINUAL WESTWARD DEVELOPMENT FOR THE NEXT SEVERAL HOURS
UNTIL MID-MORNING WHERE THEREAFTER CONDITIONS WILL IMPROVE...THIS
FORECAST PACKAGE WILL REFLECT THAT PROGRESSION.
AS PREVIOUSLY STATED...THE BEST MOISTURE AXIS WAS NOTED EAST OF THE
FA AND WITH THE AID OF A BIT OF UL SUPPORT FROM THE UA LOW ACROSS
NWRN OLD MEXICO...RADAR ANALYSIS DEPICTED SCATTERED SHOWERS
DEVELOPING ACROSS THE LOW ROLLING PLAINS AND BIG COUNTRY AREAS. WITH
THE LLJ PROGGED TO INCREASE TO 30-40 KTS ACROSS THE ROLLING PLAINS
WITHIN THE NEXT FEW HOURS COUPLED WITH INCREASING LARGE SCALE ASCENT
AND A MOISTENING ATMOSPHERE /PWATS INCREASING TO AOA 1.10
INCHES/...CHANCES FOR ADDITIONAL SHOWERS AND THUNDERSTORMS WILL BE
ON THE INCREASE PARTICULARLY ACROSS THE ROLLING PLAINS. SOME OF THIS
ACTIVITY COULD POSE A THREAT FOR MODERATE TO HEAVY RAINFALL AS
PWATS INCREASE TO ABOVE 1.00 INCH THROUGHOUT THIS MORNING.
FURTHERMORE...MID-LEVEL CAPE VALUES OF 1000-1500 J/KG COMBINED WITH
0-6 KM BULK SHEAR VALUES AOA 40 KTS...SUGGEST SOME OF THE ACTIVITY
COULD APPROACH STRONG LEVELS WITH HAIL BEING THE PRIMARY THREAT
/PARTICULARLY ACROSS THE LOW ROLLING PLAINS/. STORMS WILL LINGER INTO
EARLY AFTN WHERE THEREAFTER...MODEL SOUNDINGS EXHIBITING A DRYING
PROFILE AND THE UA LOW MOVING EAST TOWARDS SE TX WILL RESULT IN
PRECIP EXITING THE REGION. BY LATE THIS EVENING/EARLY TONIGHT...A
DEEPENING SFC LOW PROGRESSING EAST ACROSS THE CENTRAL PLAINS WILL
PROMOTE W-SW SFC WINDS TO BECOME SLIGHTLY BREEZY BY THE END OF THE
SHORT TERM PERIOD.
TEMPS WILL BE A FEW DEGREES ABOVE NORM TODAY /MIDDLE TO UPPER 60S/
FOLLOWED BY A RELATIVELY MILD NIGHT /UPPER 30S TO MIDDLE 40S/.
&&
.LONG TERM...
NO SIGNFICANT CHANGES TO THE FCST THIS MORNING. MODELS REMAIN
CONSISTENT IN KEEPING THE SRN HIGH PLAINS UNDERNEATH NORTHWESTERLY
FLOW ALOFT. A COUPLE OF SHORT WAVE TROUGHS MOVING THROUGH THIS
UPPER FLOW WILL PRODUCE A COUPLE PERIODS OF BREEZY TO WINDY
CONDITIONS SUNDAY AND MONDAY...THE STRONGEST WINDS COMING SUNDAY
ACROSS THE SWRN HALF OF THE FCST AREA...POSSIBLY MEETING ADVISORY
CRITERIA FOR A PERIOD OF TIME DURING THE AFTERNOON HOURS. TEMPS
NEAR OR JUST BELOW SEASONAL NORMS WITH THE WARMEST DAYS LIKELY
BEING WEDNESDAY AND THURSDAY. STILL SOME MODEL SOLUTIONS SHOWING
A BRIEF INCURSION OF COLD AIR TOWARD FRIDAY...BUT CERTAINLY NOW
CONSENSUS IN THAT REGARD ATTM.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 66 38 53 26 48 / 10 0 10 10 0
TULIA 66 40 56 30 50 / 20 10 10 10 0
PLAINVIEW 66 42 58 31 51 / 20 10 10 10 0
LEVELLAND 65 43 60 31 51 / 20 10 10 10 0
LUBBOCK 66 44 61 32 52 / 30 10 10 10 0
DENVER CITY 65 42 63 31 52 / 20 10 10 10 0
BROWNFIELD 66 43 63 31 53 / 30 10 10 10 0
CHILDRESS 65 45 63 37 56 / 60 10 10 10 0
SPUR 67 48 65 37 56 / 60 10 0 10 0
ASPERMONT 67 49 67 39 57 / 80 20 0 10 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
29/07
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1135 PM CST FRI NOV 21 2014
.UPDATE...
06Z TAF DISCUSSION IN AVIATION SECTION.
&&
.DISCUSSION...
MAIN CONCERN NEXT 6 HRS FOR SE TX TERMINALS WILL BE CIGS. CIG
RANGE FROM IFR TO VFR FOR AREA AIRPORTS. THINK ALL AREAS WILL HAVE
AT LEST MVFR CIGS AND POSSIBLY A FEW SHOWERS IN THE MORNING. THE
00Z NAM/GFS STILL SUPPORT 2 TIME FRAMES FOR CONVECTION WHICH THE
TAFS CAPTURE. THERE WILL BE SOME ADJUSTMENTS TO THE TAFS FOR
TIMING OF THE CONVECTION. FIRST ROUND STILL LOOKS ON TRACK FOR THE
LATER AFTERNOON HOURS. SECOND ROUND WILL BE ASSOCIATED WITH THE
UPPER LOW MOVING ACROSS THE AREA. LOOK FOR STORMS TO BE OUT OF THE
AREA BY 09Z SUN MORNING. CIGS SHOULD IMPROVE QUITE A BIT AFTER
PACIFIC FRONT PUSHES ACROSS THE AREA.
39
&&
.PREV DISCUSSION... /ISSUED 936 PM CST FRI NOV 21 2014/
DISCUSSION...
NO CHANGES TO THIS UPDATE. THE BEST WARM AIR AND MOISTURE
ADVECTION WAS TO THE WEST OF THE FORECAST AREA...GENERALLY ACROSS
THE CENTRAL PART OF THE STATE. THE 00Z NAM12 AND THE HRRR BOTH
KEEP ISOLATED TO SCATTERED RAIN CHANCES OVER THE FAR WESTERN
COUNTIES THROUGH ABOUT 3 AM. CHANCES RETURN BY LATE MORNING ON
SATURDAY.
THE MAIN EVENT STILL LOOKS TO OCCUR SATURDAY AFTERNOON AND
EVENING. THE 00Z NAM12 AND HRRR ARE A BIT SLOWER THAN THE 18Z
TEXAS TECH WRF. THE NAM12 AND HRRR PUSH AN INITIAL LINE OF STORMS
INTO SE TX DURING THE LATE AFTERNOON TO EARLY EVENING TIME PERIOD.
A SQUALL LINE THEN DEVELOPS AND MOVES OVERHEAD LATE EVENING INTO
THE OVERNIGHT PERIOD SATURDAY NIGHT. THE TEXAS TECH WRF IS ABOUT 3
HOURS OR SO QUICKER WITH THE TIMING. AFTER LOOKING OVER THE 00Z
NAMBUFR MODEL SOUNDINGS...THE CURRENT THINKING IS STILL IN LINE
WITH THE PREVIOUS REGARDING THE SEVERE THREAT -- A SLIGHT RISK
FOR SEVERE STORMS WITH DAMAGING WINDS AND HAIL THE MAIN THREATS
AND ISOLATED TORNADOES POSSIBLE.
40
PREV DISCUSSION... /ISSUED 554 PM CST FRI NOV 21 2014/
DISCUSSION...
00Z TAF DISCUSSION IN AVIATION SECTION.
AVIATION...
COMPLICATED FORECAST FOR AVIATION CONCERNS THE NEXT 24-30HRS.
CIGS TONIGHT SHOULD MOSTLY BE MVFR FOR SE TX TERMINALS. THERE IS
SOME VFR CIGS ALONG THE COAST BUT THOSE SHOULD FILL BACK IN AT
MVFR LEVELS. ONLY QUESTION WILL BE IFR CIGS WHICH LOOK MORE
POSSIBLE OVER KCLL/KUTS/KCXO BUT COULD EASILY DEVELOP OVER THE
HOUSTON AREA IN THE MORNING. MAY NEED TO ADD A TEMPO GROUP FOR IFR
WITH 06Z TAFS SHOULD THERE BE MORE CONFIDENCE IN IFR DEVELOPING.
MVFR CIGS SHOULD REMAIN AND MAY BECOME VFR IN THE AFTERNOON BUT
NOT AS LIKELY. WILL STICK WITH NAM/GFS SOLUTIONS FOR CONVECTIVE
TRENDS AT THIS MOMENT. UPPER LOW OVER AZ SHOULD BE OVER RIO GRANDE
VALLEY NEAR DRT BY 00Z SUN. LEAD SHORTWAVE SHOULD MOVE OVER SE TX
BY THIS TIME OR END OF CURRENT TAF. WAVE MAY INITIATE ONE ROUND OF
TSRA FOR THE AREA. MAIN UPPER LOW THEN MOVES TO ACT/AUS BY 06Z BY
WHICH A 2ND ROUND OF CONVECTION MAY AFFECT THE AREA. ADDED PROB30
GROUP FOR IAH TO ACCOUNT FOR THIS TIMING. OBVIOUSLY TAFS WILL
UNDERGO SEVERAL CHANGES AS THIS SYSTEM EVOLVES BUT THE MAIN
HIGHLIGHT IS TO EXPECT CONVECTION TOMORROW AFTERNOON AND NIGHT TO
DISRUPT AIRPORT OPERATIONS.
39
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 62 74 58 78 47 / 30 90 80 0 0
HOUSTON (IAH) 62 76 61 79 51 / 20 80 90 0 0
GALVESTON (GLS) 65 74 66 78 56 / 20 70 90 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH SATURDAY AFTERNOON
FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL 4 AM CST SUNDAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO
60 NM.
&&
$$
DISCUSSION...40
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
926 AM EST SAT NOV 22 2014
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 337 AM EST SAT NOV 22 2014
A SERIES OF DISTURBANCES WILL PASS OVER CENTRAL INDIANA DURING THE
FORECAST PERIOD. THE FIRST SYSTEM AND ITS ASSOCIATED WARM FRONT
WILL IMPACT THE FORECAST AREA THROUGH MONDAY NIGHT WITH MAINLY
RAIN. AFTER A LULL IN ACTIVITY...ANOTHER UPPER LEVEL TROUGH WILL
BRING SNOW SHOWERS FOR WEDNESDAY AND THURSDAY WITH A COLDER AIR
MASS IN PLACE.
&&
.NEAR TERM /THIS AFTERNOON/...
ISSUED AT 920 AM EST SAT NOV 22 2014
SURFACE ANALYSIS LATE THIS MORNING SHOWS WARMER...SOUTHERLY FLOW
IN PLACE ACROSS INDIANA AS HIGH PRESSURE WAS CENTERED OVER THE
CAROLINAS. ABUNDANT CLOUD COVER WAS STREAMING NORTHEAST FROM THE
SOUTHERN PLAINS AND INTO THE OHIO VALLEY. HRRR CONTINUES TO
SUGGEST SCT LIGHT RAIN SHOWERS CONTINUING THROUGH THE DAY...BUILD
LESSENING IN COVERAGE BY LATE THIS AFTERNOON. UPPER SUPPORT IS
MINIMAL. 290K ISENTROPIC SURFACE CONTINUES TO SHOW BROAD
ISENTROPIC LIFT AMID ONGOING WARM AIR ADVECTION. SPECIFIC
HUMIDITIES CONTINUE TO RUN OVER 6 G/KG. THUS WILL KEEP ONGOING LOW
CHANCES FOR PRECIP THIS AFTERNOON AS COVER LOOKS TO REMAIN
SPOTTY. ONGOING FORECAST HANDLES THIS WELL AND ONLY MINOR CHANGES
HAVE BEEN MADE.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
ISSUED AT 405 AM EST SAT NOV 22 2014
THE MAIN FOCUS OF THE SHORT TERM PERIOD WILL BE THE HIGH PRECIP
CHANCES AS A SURFACE LOW TRAVERSES THE AREA.
PRECIP CHANCES WILL ONLY CONTINUE TO INCREASE TONIGHT THROUGH
TOMORROW AS SURFACE LOW PROVIDES BETTER LIFT. AS A RESULT...WILL
GO WITH POPS OF 100 PERCENT STARTING TOMORROW AFTERNOON THROUGH
TOMORROW NIGHT.
AS SYSTEM MOVES NORTH INTO THE GREAT LAKES REGION ON
MONDAY...PRECIP CHANCES WILL DECREASE FROM WEST TO EAST ACROSS
CENTRAL INDIANA...ALMOST COMPLETELY OUT OF THE AREA BY TUE 00Z. A
FEW LIGHT SNOW SHOWERS CAN BE EXPECTED OVER THE NORTHERN COUNTIES
SINCE COLDER AIR WILL HAVE ALREADY FILTERED IN BY THAT POINT...BUT
NO ACCUMULATIONS ARE EXPECTED SINCE MOST OF THE MOISTURE WILL HAVE
ALREADY EXITED THE AREA.
THE ABOVE NORMAL TEMPERATURES WILL CONTINUE THROUGH THE WEEKEND WITH
HIGHS TOPPING OFF IN THE 50S ON SUNDAY. BUT THE COOLING TREND WILL
COMMENCE ON MONDAY AS HIGHS ONLY TOP OFF IN THE 40S OVER THE WESTERN
TIER OF COUNTIES.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
ISSUED AT 337 AM EST SAT NOV 22 2014
MODELS INDICATE A BROAD UPPER TROUGH WILL BE ACROSS CENTRAL AND
EASTERN CANADA AS WELL AS THE UPPER MIDWEST AND GREAT LAKES. A
SURFACE LOW OVER SOUTHEAST CANADA TUESDAY WILL MOVE ON TO THE EAST
AND HIGH PRESSURE WILL MOVE EAST ACROSS OUR REGION TUESDAY NIGHT AND
EARLY WEDNESDAY. ANOTHER AREA OF LOW PRESSURE WILL AFFECT OUR
WEATHER AS IT MOVES EAST ACROSS THE NORTHERN PORTIONS OF ILLINOIS
AND INDIANA WEDNESDAY NIGHT AND THURSDAY. WILL MENTION A SLIGHT
CHANCE OF SNOW NORTHWEST LATE WEDNESDAY AND A CHANCE OF SNOW NORTH
AND CENTRAL AND A SLIGHT CHANCE OF SNOW OR MIXED PRECIPITATION FAR
SOUTH. DRY WEATHER WILL RETURN FRIDAY AS HIGH PRESSURE OVER THE
UPPER MIDWEST BUILDS OUR WAY.
IN REGARDS TO TEMPERATURES...MODELS HAVE TRENDED A LITTLE WARMER
LATE WEDNESDAY AND THURSDAY. HOWEVER THE GFS IS OVERDOING THIS AS
IT KEEPS THE ARCTIC AIR BOTTLED ACROSS SOUTHERN CANADA AND GREAT
LAKES. THE 00Z EURO AND GEMNH MODELS PULL MORE OF THIS COLD AIR
SOUTH INTO OUR ALL REGION ESPECIALLY THURSDAY. WITH THE GFS BEING SO
WARM...CUT MOS BLEND TEMPERATURES A LITTLE AROUND THURSDAY.
OTHERWISE...ONLY MINOR TWEAKS MADE TO TEMPERATURES IN MOST OTHER
PERIODS.
&&
.AVIATION /DISCUSSION FOR THE 22/15 TAF ISSUANCE/...
ISSUED AT 910 AM EST SAT NOV 22 2014
TWEAKED CURRENT CONDITIONS ONLY. PREVIOUS DISCUSSION FOLLOWS...
MOSTLY VFR CEILINGS WITH SCATTERED LIGHT SHOWERS WILL BE THE RULE.
HIGH PRESSURE OFF THE MID ATLANTIC COAST AND LOW PRESSURE MOVING
EAST ACROSS THE NORTHERN PLAINS WILL PRODUCE A BRISK SOUTHERLY FLOW.
TIME HEIGHT CHARTS INDICATE PLENTY OF LOW LEVEL MOISTURE. HOWEVER
CEILINGS UPSTREAM ARE MOSTLY ABOVE 3 THOUSAND FEET AND CEILINGS
AROUND 4 THOUSAND FEET SHOULD BE THE RULE UNTIL SUNDAY MORNING WITH
MVFR CEILINGS BEING THE RULE SUNDAY MORNING ON.
SCATTERED LIGHT SHOWERS WILL BE THE RULE THROUGH THE PERIODS AS GULF
MOISTURE CONTINUES TO FEED NORTH INTO OUR REGION.
A STRONG LOW LEVEL JET OF 50KT WORKING ACROSS THE AREA WILL RESULT
IN SOME LLWS WHICH HAS BEEN INCLUDED. THIS LOW LEVEL JET SHOULD
WEAKEN SOME BY LATE AFTERNOON.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...TDUD
NEAR TERM...PUMA
SHORT TERM...TDUD
LONG TERM....JH
AVIATION...JH/CP
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AREA FORECAST DISCUSSION
NWS JACKSON KY
1053 AM EST SAT NOV 22 2014
.UPDATE...
ISSUED AT 1050 AM EST SAT NOV 22 2014
TEMPERATURES IN THE NORTHERN PART OF THE CWA NEAR THE BLUEGRASS
CONTINUE TO WARM INTO THE LOWER 50S WHILE A FEW VALLEY SPOTS ACROSS
THE CWA CONTINUE TO STRUGGLE UP INTO THE LOWER 40S. THEREFORE DID
FRESHEN TEMPS/DEWPOINTS ACROSS THE REGION TO MATCH CURRENT
OBS. GIVEN ABUNDANT SUNSHINE AND RETURN FLOW FROM SURFACE HIGH
TEMPERATURES ARE STILL EXPECTED TO REACH THE UPPER 50S TO LOWER 60S
AREA WIDE TODAY. WSR-88D RADAR CONTINUES TO INDICATE SOME SPRINKLES
ACROSS THE FAR NORTH CWA/BLUEGRASS REGIONS THIS MORNING. THESE
RETURNS HAVE BEEN LIGHT IN MOST CASES AND EXPECT MUCH OF THE RETURNS
SEEN ON RADAR ARE PROBABLY NOT REACHING THE GROUND. HOWEVER DID OPT
TO KEEP SPRINKLES JUST A BIT LONGER IN THE NORTHERN TIP OF THE CWA
THIS MORNING INTO AROUND THE NOON TIME FRAME GIVEN THAT REGION WOULD
LIKELY SEE THE HIGHEST RADAR RETURNS.
UPDATE ISSUED AT 747 AM EST SAT NOV 22 2014
TEMPERATURES CONTINUE TO WARM ACROSS THE AREA...ESPECIALLY OUT IN THE
WEST...WHERE EKQ IS CURRENTLY REPORTING IN THE MID 40S. FURTHER
EAST...VALLEYS STILL REMAIN DECOUPLED...WITH THE PAINTSVILLE MESONET
STILL REPORTING 20 DEGREES AND OUR COOP IN INEZ REPORTING AT 21
DEGREES. THE RADAR CONTINUES TO SHOW LIGHT RETURNS SKIMMING BY THE
BLUEGRASS COUNTIES. FORTUNATELY...TEMPERATURES HAVE WARMED ABOVE
FREEZING FOR THE MAJORITY OF THE AREA...AND THE LATEST RADAR AND
SHORT RANGE MODEL GUIDANCE CONTINUES TO SUGGEST ONLY SPRINKLES FOR
THE NEXT FEW HOURS. AS SUCH...HAVE MERELY FRESHENED UP THE
HOURLY TEMPERATURE AND DEW POINT TRENDS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 337 AM EST SAT NOV 22 2014
THE LATEST SURFACE MAP FEATURES A LARGE AREA OF HIGH PRESSURE ACROSS
THE EASTERN CONUS...WITH LOW PRESSURE CRUISING THROUGH ONTARIO.
ALOFT...FAIRLY PROGRESSIVE FLOW IS IN PLACE...WITH A WEAKER SHORT
WAVE MOVING THROUGH THE OHIO VALLEY. A STRONGER VORT IS ROTATING
ALONG NORTHERN MEXICO...WHILE ADDITIONAL SHORT WAVE ENERGY IS MOVING
ACROSS THE PACIFIC NORTHWEST.
ANOTHER CHILLY NIGHT HAS BEEN ON TAP FOR EASTERN KENTUCKY...ALTHOUGH
NOT AS COLD AS LAST NIGHT. THERE ARE A FEW VALLEYS IN THE FAR EAST
REMAINING IN THE UPPER TEENS...WHILE LOW TO MID 20S ARE COMMON IN THE
BROADER VALLEYS. RIDGETOPS ARE IN THE 30S THANKS TO LIGHT SOUTH TO
SOUTHEAST WINDS. A DECENT 850 MB JET HAS DEVELOPED ACROSS THE OHIO VALLEY
OVERNIGHT...WITH LIGHT PRECIPITATION BREAKING OUT ACROSS MOST OF
INDIANA AND DOWN INTO WESTERN KENTUCKY. THE LATEST HRRR MAY SUPPORT A
FEW SPRINKLES ACROSS THE I-64 CORRIDOR TOWARDS DAWN...HOWEVER GIVEN
THE DRY AIR IN PLACE CHANCES OF MEASURABLE PRECIPITATION LOOK LOW.
ONCE THE SPRINKLES SKIRT BY TO THE NORTH EARLY THIS MORNING...DRY
CONDITIONS WILL REMAIN IN PLACE THANKS TO LOW LEVEL SOUTHEASTERLY
FLOW. HIGHS TODAY WILL APPROACH THE 60 DEGREE MARK IN
PLACES...TEMPERATURES THAT WE HAVE NOT SEEN IN ABOUT A WEEK AND A
HALF. MEANWHILE...NORTHERN STREAM SHORT WAVE ENERGY WILL TRAVERSE THE
U.S./CANADIAN BORDER...WHILE THE SOUTHERN STREAM VORT CONTINUES TO
SLIDE EAST. THE VORT WILL THEN SWING MORE NORTHEAST...REACHING THE
TENNESSEE VALLEY BY LATE IN THE DAY ON SUNDAY. THIS WILL RESULT IN
SURFACE LOW PRESSURE ORGANIZING ACROSS THE PLAINS...EVENTUALLY
CONGLOMERATING ACROSS THE OHIO VALLEY LATE IN THE PERIOD.
EASTERN KENTUCKY WILL ENJOY A MILDER NIGHT TONIGHT...AS WARM AIR
ADVECTION CONTINUES OUT AHEAD OF THE APPROACHING SYSTEM FROM THE
WEST. LOWS WILL BOTTOM OUT IN THE LOWER 30S IN THE MORE SHELTERED
VALLEYS IN THE EAST...WHILE OTHER LOCATIONS WILL SEE UPPER 30S AND
LOWER 40S. A WARM FRONT/MID-LEVEL SHORT WAVE WILL APPROACH THE AREA
FROM THE SOUTHWEST ON SUNDAY...WITH WIDESPREAD SHOWER ACTIVITY
BREAKING OUT ACROSS EASTERN KENTUCKY IN THE AFTERNOON. HAVE CONTINUED
TO DOWNPLAY THE QPF AMOUNTS IN THE FAR EAST WITH DOWNSLOPE FLOW IN
PLACE. DESPITE THE SHOWERS MOVING IN...HIGHS WILL MAKE IT BACK INTO
THE UPPER 50S AND LOWER 60S.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 337 AM EST SAT NOV 22 2014
STILL SOME QUESTION AS TO HOW FAST THE TROUGH AXIS SHIFTS TO THE
NORTH SUNDAY EVENING. GFS IS MUCH MORE PROGRESSIVE ON BRINGING THE
DRY SLOT IN QUICKLY SUNDAY EVENING...WHILE THE ECMWF HOLDS IT BACK
EARLY ON. BASIC THINKING IS THAT EVEN IF THE DRY SLOT MOVES IN
FASTER...WE MAY STILL GET DEVELOPMENT INTO THE WARM SECTOR THROUGH
THE NIGHT OR POSSIBLY EVEN SOME MEASURABLE DRIZZLE. THUS...WILL
MAINTAIN HIGH CHANCE TO LIKELY POPS THROUGH THE FIRST HALF OF THE
NIGHT...WITH DRIZZLE BECOMING MORE LIKELY AS THE NIGHT PROGRESSES.
ON MONDAY...A SHARP COLD FRONT WILL PUSH INTO AND CROSS THE AREA.
THIS SHOULD AGAIN BRING HIGHER CHANCES FOR SHOWERS AS IT CROSSES THE
AREA THROUGH EARLY TO MID AFTERNOON. IN THE WAKE OF THE
FRONT...TEMPERATURES WILL TAKE A TUMBLE IN THE AFTERNOON AND EVENING
HOURS. AFTER CLIMBING INTO THE LOW 60S...TEMPERATURES BY THE EVENING
SHOULD SETTLE BACK INTO THE 40S. STILL LOOKS LIKE A WINDY DAY...WITH
925MB WINDS TOPPING 35 KNOTS AS THE FRONT CROSSES THE AREA. ANY
SHOWER ACTIVITY MAY ACTUALLY HELP TO MIX DOWN SOME ISOLATED HIGHER
GUSTS TO 40 OR 45 MPH.
SURFACE HIGH PRESSURE SHOULD MOVE INTO THE OHIO RIVER VALLEY MONDAY
NIGHT WITH DRY WEATHER RETURNING. ATTENTION WILL THEN TURN TO A
POSSIBLE NOREASTER AS AN AREA OF LOW PRESSURE MOVES UP THE EASTERN
US COAST. 00Z ECMWF HAS SHIFTED THE TRACK OF THIS LOW BACK TO THE
WEST...BRINGING MOISTURE INTO THE APPALACHIAN MOUNTAINS. GOING TO
MAINTAIN THE DRY FORECAST...BUT IF THIS SYSTEM TRENDS ANY FARTHER
WEST...MAY NEED TO INSERT SOME POPS BY WEDNESDAY.
MODELS REALLY DIVERGE THEREAFTER AS WE HEAD INTO THANKSGIVING DAY.
GFS BUILDS A RIDGE OVER THE OHIO RIVER VALLEY...SUGGESTING
TEMPERATURES MAY REACH INTO THE 50S...WHILE THE ECMWF DIGS OUT
ANOTHER SHARP TROUGH AND WOULD PUT TEMPERATURES MORE INTO THE 30S
WITH A GOOD CHANCE FOR SNOW. CLEARLY THIS IS A LARGE DIFFERENCE IN
THE MODELS...AND PUTS LOTS OF UNCERTAINTY ON THE THANKSGIVING
FORECAST AND BEYOND. FOR NOW...WILL GO WITH A COMPROMISED
FORECAST...WITH A SLIGHT EDGE TOWARDS THE COLDER ECMWF AS IT HAS
BEEN VERY CONSISTENT ON THE COLDER SOLUTION. WILL ALSO MAINTAIN LOW
POPS WEDNESDAY NIGHT INTO THURSDAY NIGHT...AND GO WITH A MIXTURE OF
RAIN/SNOW THROUGH THIS PERIOD. IT DOES LOOK REGARDLESS OF
THANKSGIVING DAY...MODELS POINT TO A MUCH COLDER END TO THE
WEEK...WITH TEMPERATURES STAYING WELL BELOW NORMAL INTO FRIDAY AND
SATURDAY. WE SHOULD SEE DRIER WEATHER FOR FRIDAY AND SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 747 AM EST SAT NOV 22 2014
EXPECT VFR CONDITIONS TO HOLD ON THROUGH THE PERIOD. SOME PASSING LOW
CLOUDS BETWEEN 4 AND 5K FEET AGL WILL BE SEEN THIS MORNING...AND THEN
ONCE AGAIN BETWEEN 06 AND 12Z. OTHERWISE MOST CLOUD COVER WILL BE AT
OR ABOVE 10K FEET AGL. WINDS WILL REMAIN OUT OF THE SOUTH AND
SOUTHEAST...AT OR AROUND 5 KTS THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...GEOGERIAN
LONG TERM...KAS
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
747 AM EST SAT NOV 22 2014
.UPDATE...
ISSUED AT 747 AM EST SAT NOV 22 2014
TEMPERATURES CONTINUE TO WARM ACROSS THE AREA...ESPECIALLY OUT IN THE
WEST...WHERE EKQ IS CURRENTLY REPORTING IN THE MID 40S. FURTHER
EAST...VALLEYS STILL REMAIN DECOUPLED...WITH THE PAINTSVILLE MESONET
STILL REPORTING 20 DEGREES AND OUR COOP IN INEZ REPORTING AT 21
DEGREES. THE RADAR CONTINUES TO SHOW LIGHT RETURNS SKIMMING BY THE
BLUEGRASS COUNTIES. FORTUNATELY...TEMPERATURES HAVE WARMED ABOVE
FREEZING FOR THE MAJORITY OF THE AREA...AND THE LATEST RADAR AND
SHORT RANGE MODEL GUIDANCE CONTINUES TO SUGGEST ONLY SPRINKLES FOR
THE NEXT FEW HOURS. AS SUCH...HAVE MERELY FRESHENED UP THE
HOURLY TEMPERATURE AND DEW POINT TRENDS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 337 AM EST SAT NOV 22 2014
THE LATEST SURFACE MAP FEATURES A LARGE AREA OF HIGH PRESSURE ACROSS
THE EASTERN CONUS...WITH LOW PRESSURE CRUISING THROUGH ONTARIO.
ALOFT...FAIRLY PROGRESSIVE FLOW IS IN PLACE...WITH A WEAKER SHORT
WAVE MOVING THROUGH THE OHIO VALLEY. A STRONGER VORT IS ROTATING
ALONG NORTHERN MEXICO...WHILE ADDITIONAL SHORT WAVE ENERGY IS MOVING
ACROSS THE PACIFIC NORTHWEST.
ANOTHER CHILLY NIGHT HAS BEEN ON TAP FOR EASTERN KENTUCKY...ALTHOUGH
NOT AS COLD AS LAST NIGHT. THERE ARE A FEW VALLEYS IN THE FAR EAST
REMAINING IN THE UPPER TEENS...WHILE LOW TO MID 20S ARE COMMON IN THE
BROADER VALLEYS. RIDGETOPS ARE IN THE 30S THANKS TO LIGHT SOUTH TO
SOUTHEAST WINDS. A DECENT 850 MB JET HAS DEVELOPED ACROSS THE OHIO VALLEY
OVERNIGHT...WITH LIGHT PRECIPITATION BREAKING OUT ACROSS MOST OF
INDIANA AND DOWN INTO WESTERN KENTUCKY. THE LATEST HRRR MAY SUPPORT A
FEW SPRINKLES ACROSS THE I-64 CORRIDOR TOWARDS DAWN...HOWEVER GIVEN
THE DRY AIR IN PLACE CHANCES OF MEASURABLE PRECIPITATION LOOK LOW.
ONCE THE SPRINKLES SKIRT BY TO THE NORTH EARLY THIS MORNING...DRY
CONDITIONS WILL REMAIN IN PLACE THANKS TO LOW LEVEL SOUTHEASTERLY
FLOW. HIGHS TODAY WILL APPROACH THE 60 DEGREE MARK IN
PLACES...TEMPERATURES THAT WE HAVE NOT SEEN IN ABOUT A WEEK AND A
HALF. MEANWHILE...NORTHERN STREAM SHORT WAVE ENERGY WILL TRAVERSE THE
U.S./CANADIAN BORDER...WHILE THE SOUTHERN STREAM VORT CONTINUES TO
SLIDE EAST. THE VORT WILL THEN SWING MORE NORTHEAST...REACHING THE
TENNESSEE VALLEY BY LATE IN THE DAY ON SUNDAY. THIS WILL RESULT IN
SURFACE LOW PRESSURE ORGANIZING ACROSS THE PLAINS...EVENTUALLY
CONGLOMERATING ACROSS THE OHIO VALLEY LATE IN THE PERIOD.
EASTERN KENTUCKY WILL ENJOY A MILDER NIGHT TONIGHT...AS WARM AIR
ADVECTION CONTINUES OUT AHEAD OF THE APPROACHING SYSTEM FROM THE
WEST. LOWS WILL BOTTOM OUT IN THE LOWER 30S IN THE MORE SHELTERED
VALLEYS IN THE EAST...WHILE OTHER LOCATIONS WILL SEE UPPER 30S AND
LOWER 40S. A WARM FRONT/MID-LEVEL SHORT WAVE WILL APPROACH THE AREA
FROM THE SOUTHWEST ON SUNDAY...WITH WIDESPREAD SHOWER ACTIVITY
BREAKING OUT ACROSS EASTERN KENTUCKY IN THE AFTERNOON. HAVE CONTINUED
TO DOWNPLAY THE QPF AMOUNTS IN THE FAR EAST WITH DOWNSLOPE FLOW IN
PLACE. DESPITE THE SHOWERS MOVING IN...HIGHS WILL MAKE IT BACK INTO
THE UPPER 50S AND LOWER 60S.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 337 AM EST SAT NOV 22 2014
STILL SOME QUESTION AS TO HOW FAST THE TROUGH AXIS SHIFTS TO THE
NORTH SUNDAY EVENING. GFS IS MUCH MORE PROGRESSIVE ON BRINGING THE
DRY SLOT IN QUICKLY SUNDAY EVENING...WHILE THE ECMWF HOLDS IT BACK
EARLY ON. BASIC THINKING IS THAT EVEN IF THE DRY SLOT MOVES IN
FASTER...WE MAY STILL GET DEVELOPMENT INTO THE WARM SECTOR THROUGH
THE NIGHT OR POSSIBLY EVEN SOME MEASURABLE DRIZZLE. THUS...WILL
MAINTAIN HIGH CHANCE TO LIKELY POPS THROUGH THE FIRST HALF OF THE
NIGHT...WITH DRIZZLE BECOMING MORE LIKELY AS THE NIGHT PROGRESSES.
ON MONDAY...A SHARP COLD FRONT WILL PUSH INTO AND CROSS THE AREA.
THIS SHOULD AGAIN BRING HIGHER CHANCES FOR SHOWERS AS IT CROSSES THE
AREA THROUGH EARLY TO MID AFTERNOON. IN THE WAKE OF THE
FRONT...TEMPERATURES WILL TAKE A TUMBLE IN THE AFTERNOON AND EVENING
HOURS. AFTER CLIMBING INTO THE LOW 60S...TEMPERATURES BY THE EVENING
SHOULD SETTLE BACK INTO THE 40S. STILL LOOKS LIKE A WINDY DAY...WITH
925MB WINDS TOPPING 35 KNOTS AS THE FRONT CROSSES THE AREA. ANY
SHOWER ACTIVITY MAY ACTUALLY HELP TO MIX DOWN SOME ISOLATED HIGHER
GUSTS TO 40 OR 45 MPH.
SURFACE HIGH PRESSURE SHOULD MOVE INTO THE OHIO RIVER VALLEY MONDAY
NIGHT WITH DRY WEATHER RETURNING. ATTENTION WILL THEN TURN TO A
POSSIBLE NOREASTER AS AN AREA OF LOW PRESSURE MOVES UP THE EASTERN
US COAST. 00Z ECMWF HAS SHIFTED THE TRACK OF THIS LOW BACK TO THE
WEST...BRINGING MOISTURE INTO THE APPALACHIAN MOUNTAINS. GOING TO
MAINTAIN THE DRY FORECAST...BUT IF THIS SYSTEM TRENDS ANY FARTHER
WEST...MAY NEED TO INSERT SOME POPS BY WEDNESDAY.
MODELS REALLY DIVERGE THEREAFTER AS WE HEAD INTO THANKSGIVING DAY.
GFS BUILDS A RIDGE OVER THE OHIO RIVER VALLEY...SUGGESTING
TEMPERATURES MAY REACH INTO THE 50S...WHILE THE ECMWF DIGS OUT
ANOTHER SHARP TROUGH AND WOULD PUT TEMPERATURES MORE INTO THE 30S
WITH A GOOD CHANCE FOR SNOW. CLEARLY THIS IS A LARGE DIFFERENCE IN
THE MODELS...AND PUTS LOTS OF UNCERTAINTY ON THE THANKSGIVING
FORECAST AND BEYOND. FOR NOW...WILL GO WITH A COMPROMISED
FORECAST...WITH A SLIGHT EDGE TOWARDS THE COLDER ECMWF AS IT HAS
BEEN VERY CONSISTENT ON THE COLDER SOLUTION. WILL ALSO MAINTAIN LOW
POPS WEDNESDAY NIGHT INTO THURSDAY NIGHT...AND GO WITH A MIXTURE OF
RAIN/SNOW THROUGH THIS PERIOD. IT DOES LOOK REGARDLESS OF
THANKSGIVING DAY...MODELS POINT TO A MUCH COLDER END TO THE
WEEK...WITH TEMPERATURES STAYING WELL BELOW NORMAL INTO FRIDAY AND
SATURDAY. WE SHOULD SEE DRIER WEATHER FOR FRIDAY AND SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 747 AM EST SAT NOV 22 2014
EXPECT VFR CONDITIONS TO HOLD ON THROUGH THE PERIOD. SOME PASSING LOW
CLOUDS BETWEEN 4 AND 5K FEET AGL WILL BE SEEN THIS MORNING...AND THEN
ONCE AGAIN BETWEEN 06 AND 12Z. OTHERWISE MOST CLOUD COVER WILL BE AT
OR ABOVE 10K FEET AGL. WINDS WILL REMAIN OUT OF THE SOUTH AND
SOUTHEAST...AT OR AROUND 5 KTS THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...GEOGERIAN
LONG TERM...KAS
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
555 AM CST SAT NOV 22 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 440 AM CST SAT NOV 22 2014
WARM AIR ADVECTION REGIME IS THE MAIN STORY OF THE SHORT TERM
PERIOD. BRISK SOUTHERLY WINDS HAVE ALLOWED TEMPERATURES TO CLIMB
ABOVE FREEZING /FOR THE FIRST TIME IN NEARLY TWO WEEKS/ OVERNIGHT
ACROSS SOUTHERN MN AND WESTERN WI. SURFACE DEW POINTS IN THE LOW
TO MID 30S CONTINUE TO PUSH NORTHWARD THROUGH IOWA AND WILL
CONTINUE FILLING IN ACROSS EASTERN MN AND WESTERN WI. WENT WITH A
PESSIMISTIC CLOUD/FOG FORECAST COMPARED TO MUCH OF THE GUIDANCE
WITH THE RELATIVE WARM AND MOIST AIR STREAMING NORTHWARD OVER THE
CURRENT SNOW PACK. DEW POINTS ACROSS WESTERN MN WILL LIKELY REMAIN
BELOW FREEZING THROUGH THE DAY AS THE BEST MOISTURE ADVECTION
STREAMING NORTHWARD TAKES AN EASTWARD TURN. MUCH OF SOUTHEASTERN
MN AND WESTERN WI ARE CURRENTLY SOCKED IN WITH LOW STRATUS AND
FOG...BUT MOSTLY CLEAR SKIES CAN BE FOUND TO THE WEST. THE HRRR
HAS PERFORMED WELL WITH THE COVERAGE OF THE CLOUDS/FOG...SO
WEIGHTED HEAVILY WITH THE HRRR IN THE SHORT RANGE FORECAST. THE
STRATUS DECK IS EXPECTED TO EXPAND SOME TO THE WEST THROUGH THE
MORNING...AND KEEP EASTERN MN AND WESTERN WI SOCKED IN THROUGH THE
DAY.
A COMPLICATED EVOLUTION OF THE FORECAST FOR TONIGHT THROUGH EARLY
SUNDAY MORNING. A NORTHERN STREAM SHORTWAVE WILL MOVE ACROSS
SOUTHERN CANADA TODAY AND MAKE IT TO MANITOBA TONIGHT.
MEANWHILE...THE SOUTHERN STREAM WAVE WILL BE PIVOTING OVER THE
SOUTHERN CONUS. THE BEST AREA OF LIFT WILL LARGELY REMAIN SOUTH OF
OUR AREA TONIGHT...BUT SOME MARGINAL LIFT ARRIVES TONIGHT AND WITH
SATURATED LOW LEVELS...DRIZZLE/LIGHT RAIN WILL BE POSSIBLE ACROSS
EASTERN MN AND WESTERN WI. WITH MODEL SOUNDINGS ALSO INDICATING A
VERY SATURATED NEAR SURFACE ENVIRONMENT...EXPANDED MENTION OF FOG IN
THE FORECAST...ESPECIALLY FOR WESTERN WI.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 440 AM CST SAT NOV 22 2014
A MILD START TO THE LONG TERM PERIOD PRIOR TO THE MERGING OF
NORTHERN AND SOUTHERN STREAM WAVES...AND THEN ANOTHER SURGE OF
ARCTIC AIR BLASTS THE REGION.
00Z MODEL SOLUTIONS WERE FAIRLY SIMILAR IN THEIR DEPICTION OF POPS
FOR SUNDAY...WITH THE FORECAST AREA BEING SOMEWHAT CAUGHT BETWEEN
THE TWO MAIN AREAS OF FORCING ASSOCIATED WITH THE AFOREMENTIONED
WAVES. THIS WILL MEAN SUNDAY WILL BE A FOGGY DAY WITH OVERCAST
SKIES...BUT THE BULK OF THE MEASURABLE PRECIP WILL REMAIN OUTSIDE
OF THE AREA ON SUNDAY. THE EXCEPTION WILL BE THE EASTERN FORECAST
AREA TOWARD EAU CLAIRE...WHICH WILL BE ON THE WESTERN EDGE OF THE
H85 MOISTURE TRANSPORT.
ON SUNDAY NIGHT...COLDER AIR BEGINS TO INFILTRATE THE AREA AS THE
PARENT SURFACE LOW LIFTS TO LAKE SUPERIOR. THE TWO PRIMARY
CONCERNS AS THIS OCCURS WILL BE VERY STRONG WINDS AND SNOW/BLOWING
SNOW. THE HIGHEST WINDS ARE FORECAST IN THE TYPICAL WEST/SOUTH
CENTRAL MN AREAS...WHERE MODELS INDICATE 40-45KTS AT THE TOP OF
THE CHANNEL. THE STRONGER FORCING FOR SNOW IS FORECAST TO BE A BIT
REMOVED FROM THE STRONGER WINDS /NORTHERN MN/WI/...SO IT REMAINS
TO BE SEEN HOW SIGNIFICANT VISIBILITY REDUCTIONS WILL BE GIVEN THE
SNOWPACK WILL HAVE ENDURED MELTING/RE-FREEZING/DRIZZLE.
WINDS SETTLE DOWN ON TUESDAY...THEN 850 MB TEMPS REDUCE TO AROUND
-15C LATE WEDNESDAY. ANOTHER WEAK WAVE CLIPS THE AREA ON
WEDNESDAY...BRINGING 20-30 PERCENT SNOW CHANCES. THESE VALUES
ARE AROUND 2 STANDARD DEVIATIONS BELOW NORMAL...AND TRANSLATE TO A
CHILLY THANKSGIVING DAY WITH HIGHS IN THE UPPER SINGLE DIGITS TO
MID TEENS. TEMPS REBOUND NICELY ON FRIDAY HOWEVER...WHEN HIGHS ARE
EXPECTED TO WARM INTO THE LOW/MID 20S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 542 AM CST SAT NOV 22 2014
WARM AND MOIST AIR CONTINUES ADVECTING NORTHWARD THIS MORNING AND
WILL PERSIST THROUGH THE PERIOD. WIDESPREAD LOW STRATUS AND FOG
WILL BE THE RULE AS LOW LEVEL SATURATION IS ONLY AIDED BY A
MELTING SNOW PACK AND SOUTHERLY MOISTURE ADVECTION. CHALLENGES LIE
IN TIMING OF IFR AND LIFR IMPACTS FOR EACH SITE...BUT OVERALL
EXPECT LOW CIGS TO REMAIN FOR THE EASTERN HALF TODAY...AS LOW
STRATUS SPREADS TO THE WEST SLOWLY AND WILL EVENTUALLY IMPACT ALL
TAF SITES. WESTERN SITES WILL SEE IMPROVEMENT FIRST AS DRIER AIR
LOOKS TO PUSH IN FROM THE DAKOTAS. THE FURTHER EAST YOU GO...THE
CONDITIONS WILL BE WORSE AND LAST LONGER. INCLUDED -DZ AT EAU
CLAIRE FOR TONIGHT AS MODEST LIFT MOVES THROUGH WESTERN WI. THE
ENTIRE ARE WILL BE SUSCEPTIBLE TO LOW VISIBILITIES IN FOG TONIGHT.
KMSP...IFR OR LOWER WILL BE COMMON...BUT CEILINGS MIGHT BE ABLE TO
SNEAK UP TO 1K FT THIS AFTERNOON BEFORE LOWERING AGAIN TONIGHT.
NOT TOO CONFIDENT IN THE VSBY FORECAST...ESPECIALLY TONIGHT. BUT
WANTED TO ADVERTISE THAT VIS COULD FALL QUITE LOW BY EARLY SUNDAY
MORNING. -DZ IS POSSIBLE TONIGHT BUT LOOKS MORE PROMISING
EAST...SO LEFT IT OUT OF THE TAF FOR NOW.
/OUTLOOK FOR KMSP/
SUN...MVFR/IFR WITH FZDZ/-RA POSSIBLE. WINDS SE 10 KT.
MON...MVFR/IFR WITH -SN/BLSN POSSIBLE. WINDS NW 25G30 KT.
TUES...VFR/MVFR WITH -SN POSSIBLE EARLY. WINDS NW 10 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...SPD
LONG TERM...LS
AVIATION...SPD
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
440 AM CST SAT NOV 22 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 440 AM CST SAT NOV 22 2014
WARM AIR ADVECTION REGIME IS THE MAIN STORY OF THE SHORT TERM
PERIOD. BRISK SOUTHERLY WINDS HAVE ALLOWED TEMPERATURES TO CLIMB
ABOVE FREEZING /FOR THE FIRST TIME IN NEARLY TWO WEEKS/ OVERNIGHT
ACROSS SOUTHERN MN AND WESTERN WI. SURFACE DEW POINTS IN THE LOW
TO MID 30S CONTINUE TO PUSH NORTHWARD THROUGH IOWA AND WILL
CONTINUE FILLING IN ACROSS EASTERN MN AND WESTERN WI. WENT WITH A
PESSIMISTIC CLOUD/FOG FORECAST COMPARED TO MUCH OF THE GUIDANCE
WITH THE RELATIVE WARM AND MOIST AIR STREAMING NORTHWARD OVER THE
CURRENT SNOW PACK. DEW POINTS ACROSS WESTERN MN WILL LIKELY REMAIN
BELOW FREEZING THROUGH THE DAY AS THE BEST MOISTURE ADVECTION
STREAMING NORTHWARD TAKES AN EASTWARD TURN. MUCH OF SOUTHEASTERN
MN AND WESTERN WI ARE CURRENTLY SOCKED IN WITH LOW STRATUS AND
FOG...BUT MOSTLY CLEAR SKIES CAN BE FOUND TO THE WEST. THE HRRR
HAS PERFORMED WELL WITH THE COVERAGE OF THE CLOUDS/FOG...SO
WEIGHTED HEAVILY WITH THE HRRR IN THE SHORT RANGE FORECAST. THE
STRATUS DECK IS EXPECTED TO EXPAND SOME TO THE WEST THROUGH THE
MORNING...AND KEEP EASTERN MN AND WESTERN WI SOCKED IN THROUGH THE
DAY.
A COMPLICATED EVOLUTION OF THE FORECAST FOR TONIGHT THROUGH EARLY
SUNDAY MORNING. A NORTHERN STREAM SHORTWAVE WILL MOVE ACROSS
SOUTHERN CANADA TODAY AND MAKE IT TO MANITOBA TONIGHT.
MEANWHILE...THE SOUTHERN STREAM WAVE WILL BE PIVOTING OVER THE
SOUTHERN CONUS. THE BEST AREA OF LIFT WILL LARGELY REMAIN SOUTH OF
OUR AREA TONIGHT...BUT SOME MARGINAL LIFT ARRIVES TONIGHT AND WITH
SATURATED LOW LEVELS...DRIZZLE/LIGHT RAIN WILL BE POSSIBLE ACROSS
EASTERN MN AND WESTERN WI. WITH MODEL SOUNDINGS ALSO INDICATING A
VERY SATURATED NEAR SURFACE ENVIRONMENT...EXPANDED MENTION OF FOG IN
THE FORECAST...ESPECIALLY FOR WESTERN WI.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 440 AM CST SAT NOV 22 2014
A MILD START TO THE LONG TERM PERIOD PRIOR TO THE MERGING OF
NORTHERN AND SOUTHERN STREAM WAVES...AND THEN ANOTHER SURGE OF
ARCTIC AIR BLASTS THE REGION.
00Z MODEL SOLUTIONS WERE FAIRLY SIMILAR IN THEIR DEPICTION OF POPS
FOR SUNDAY...WITH THE FORECAST AREA BEING SOMEWHAT CAUGHT BETWEEN
THE TWO MAIN AREAS OF FORCING ASSOCIATED WITH THE AFOREMENTIONED
WAVES. THIS WILL MEAN SUNDAY WILL BE A FOGGY DAY WITH OVERCAST
SKIES...BUT THE BULK OF THE MEASURABLE PRECIP WILL REMAIN OUTSIDE
OF THE AREA ON SUNDAY. THE EXCEPTION WILL BE THE EASTERN FORECAST
AREA TOWARD EAU CLAIRE...WHICH WILL BE ON THE WESTERN EDGE OF THE
H85 MOISTURE TRANSPORT.
ON SUNDAY NIGHT...COLDER AIR BEGINS TO INFILTRATE THE AREA AS THE
PARENT SURFACE LOW LIFTS TO LAKE SUPERIOR. THE TWO PRIMARY
CONCERNS AS THIS OCCURS WILL BE VERY STRONG WINDS AND SNOW/BLOWING
SNOW. THE HIGHEST WINDS ARE FORECAST IN THE TYPICAL WEST/SOUTH
CENTRAL MN AREAS...WHERE MODELS INDICATE 40-45KTS AT THE TOP OF
THE CHANNEL. THE STRONGER FORCING FOR SNOW IS FORECAST TO BE A BIT
REMOVED FROM THE STRONGER WINDS /NORTHERN MN/WI/...SO IT REMAINS
TO BE SEEN HOW SIGNIFICANT VISIBILITY REDUCTIONS WILL BE GIVEN THE
SNOWPACK WILL HAVE ENDURED MELTING/RE-FREEZING/DRIZZLE.
WINDS SETTLE DOWN ON TUESDAY...THEN 850 MB TEMPS REDUCE TO AROUND
-15C LATE WEDNESDAY. ANOTHER WEAK WAVE CLIPS THE AREA ON
WEDNESDAY...BRINGING 20-30 PERCENT SNOW CHANCES. THESE VALUES
ARE AROUND 2 STANDARD DEVIATIONS BELOW NORMAL...AND TRANSLATE TO A
CHILLY THANKSGIVING DAY WITH HIGHS IN THE UPPER SINGLE DIGITS TO
MID TEENS. TEMPS REBOUND NICELY ON FRIDAY HOWEVER...WHEN HIGHS ARE
EXPECTED TO WARM INTO THE LOW/MID 20S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1046 PM CST FRI NOV 21 2014
LOW CLOUDS ARE CURRENTLY BEING ADVECTED NORTHWARD THROUGH SOUTHEAST
MN AND WESTERN WI. THIS STRATUS DECK WILL CONTINUE TO OVERSPREAD
EASTERN TERMINALS...WHERE IFR CIGS WILL DEVELOP WITHIN THE NEXT
COUPLE HOURS. THE LOW STRATUS DECK OVER EASTERN TERMINALS SHOULD
BUILD NORTHWESTWARD BY SATURDAY MORNING...AND IFR/LIFR CIGS COULD
DEVELOP OVER ALL TERMINALS BY THIS TIME. THE POTENTIAL FOR PATCHY
FOG ALSO EXISTS...AS THE HRRR AND HOPWRF SHOW VISIBILITIES LESS THAN
A MILE ACROSS THE REGION SATURDAY MORNING. WHILE THERE IS STILL SOME
DISAGREEMENT...MOST MODELS SHOW THE POTENTIAL FOR A PROLONGED PERIOD
OF IFR/LIFR CIGS AT ALL TERMINALS THROUGH SATURDAY EVENING AS WARM
MOIST AIR IS ADVECTED OVER THE SNOW PACK.
KMSP...IFR CIGS WILL DEVELOP WITHIN THE NEXT COUPLE HOURS AS A LOW
CLOUD DECK DEVELOPS. IFR/LIFR CIGS AND REDUCED VISIBILITIES ARE
LIKELY SATURDAY MORNING THROUGH THE EVENING AS LOW CLOUDS AND
POSSIBLY PATCHY FOG PERSIST. MEASURABLE PRECIP SHOULD REMAIN TO THE
SOUTHEAST ON SATURDAY WITH SOME PATCHY DRIZZLE POSSIBLE IN THE
EVENING...THOUGH CHANCES OF PRECIPITATION REMAIN LOW.
/OUTLOOK FOR KMSP/
SUN...MVFR/IFR WITH FZDZ/-RA POSSIBLE. WINDS SE 10 KT.
MON...MVFR/IFR WITH -SN/BLSN POSSIBLE. WINDS NW 25G30 KT.
TUES...VFR/MVFR WITH -SN POSSIBLE EARLY. WINDS NW 10 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...SPD
LONG TERM...LS
AVIATION...ADL
AREA FORECAST DISCUSSION
NWS RALEIGH NC
705 AM EST SAT NOV 22 2014
.SYNOPSIS...HIGH PRESSURE REMAINS OVER THE REGION TODAY INTO
TONIGHT. A STRONG LOW PRESSURE MOVING FROM THE SOUTHERN PLAINS INTO
THE GREAT LAKES SUNDAY WILL SPREAD MOISTURE OVER THE REGION DURING
THE DAY ON SUNDAY. ANOTHER COLD FRONT WILL MOVE EAST ACROSS MUCH OF
THE AREA MONDAY...WITH LOW PRESSURE MOVING ALONG THE SOUTHEAST COAST
TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM SATURDAY...
THE LATEST SURFACE ANALYSIS SHOWED SURFACE HIGH PRESSURE OVER
CENTRAL NORTH CAROLINA...AND THE 00Z UPPER-AIR ANALYSIS NOTED VERY
DRY AIR AT 850MB WITH DEW POINT DEPRESSIONS WELL ABOVE 40C. THE
TEMPERATURE HAD FALLEN INTO THE UPPER TEENS AT LEAST AT KTDF...AND
WATCHING THE KRDU OVERNIGHT LOW SO FAR THE LOW WAS 25 AS OF THIS
WRITING. FOR TODAY...BUFR SOUNDINGS ARE CONTINUED DRY AND STABLE.
THE HRRR WRF FORECASTS NOTICEABLE HIGH CLOUDS TODAY...BUT OTHER
GUIDANCE SUCH AS THE CANADIAN CLOUD COVER MODEL...AND WHAT ONE WOULD
CONSIDER LOOKING AT THE UPPER-LEVEL RELATIVE HUMIDITY FORECASTS AND
BUFR SOUNDINGS...SUGGEST LESS. SATELLITE DATA UPSTREAM SUGGEST LESS
AS WELL...ALONG WITH THE JET LIFTING NORTH. UNDER EXPECTED SUNSHINE
HIGHS SHOULD BE 50 TO 55.
OVERNIGHT...CLOUDS SHOULD GRADUALLY INCREASE...BUT IT MAY BE A SLOW
INCREASE AS THE AIR MASS REMAINS DRY IN THE MEAN AT LEAST THROUGH
06Z MONDAY...AND MOISTURE ALOFT DOES NOT SHOW A STRONG INCREASE ON
BUFR SOUNDINGS UNTIL LATE TONIGHT. THE CANADIAN CLOUD COVER MODEL
ALSO SHOWS A SLOW AND GRADUAL INCREASE...AND EVEN A FEW AREAS OF
MOSTLY CLEAR TO PARTLY CLOUDY CONDITIONS ESPECIALLY NORTHEAST EVEN
LATE TONIGHT. OVERNIGHT LOWS WILL BE FORECAST ON THE COLD SIDE OF
GUIDANCE AND A FEW OF THESE LOWS MAY EVEN BE TOO HIGH IF LESS CLOUDS
OCCUR FOR LONGER PERIODS IN THE OVERNIGHT. UNDER THE WESTWARD
EXTENSION OF THE RIDGE...WINDS SHOULD BE LIGHT FOR MUCH OF THE NIGHT.
WILL KEEP A DRY FORECAST AS BOTH THE GFS AND NAM SEEM TO BE A LITTLE
SLOWER WITH THE APPROACH OF DEEPER MOISTURE. BY 12Z SUNDAY...THE NAM
IS FAIRLY MOIST ALOFT...BUT THE SUB-CLOUD LAYER REMAINS VERY DRY.
THE 850MB THETA-E GRADIENT IS JUST BEGINNING TO APPROACH CENTRAL
NORTH CAROLINA ON BOTH THE NAM AND GFS AT 12Z SUNDAY...AND THOSE
MODELS ARE ALSO SUBSIDENT AT THAT LAYER AT THAT TIME. DESPITE THE
DRY SUB-CLOUD LAYER...IF ANY PRECIPITATION WOULD OCCUR OVER THE FAR
SOUTHWEST PIEDMONT...FOR EXAMPLE...SUFFICIENT WARMING ALOFT PUSHES
THICKNESSES WELL INTO THE LIQUID CATEGORY...AND SURFACE WET BULB
TEMPERATURES ARE ABOVE FREEZING. IF ANYTHING DOES OCCUR...IT WOULD
BE VERY CLOSE TO 12Z SUNDAY AND THEN ALMOST CERTAINLY IN THE FORM OF
SPRINKLES.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...
THE NAM AND THE GFS ARE SLOW TO BRING IN GOOD LIFT TO CENTRAL NORTH
CAROLINA SUNDAY. HOWEVER...NUMEROUS PARAMETERS...INCLUDING 850MB
THETA-E...K INDICES...GENERAL 850MB LIFT...700MB VORTICITY...AMONG
OTHERS SUGGEST THAT PRECIPITATION WILL MOVE IN FROM THE SOUTHWEST
WITH THE GREATEST LIKELIHOOD OF RAIN IN CENTRAL NORTH CAROLINA FROM
ABOUT 18Z TO 05Z. HAVE CONFINED THE HIGHEST CHANCES IN THE GRIDDED
FORECAST FROM 20Z TO 04Z...AND SOME OF THE WRF GUIDANCE IS EVEN
SLOWER THAN THAT WITH THE ONSET PARTICULARLY FROM THE TRIANGLE NORTH
AND EAST. FUTURE FORECASTS MAY END UP TRENDING A LITTLE SLOWER...BUT
FOR PLANNING PURPOSES ANTICIPATE HIGH PROBABILITIES OF RAIN DURING
THE AFOREMENTIONED WINDOW.
CLOUDS SHOULD INCREASE...THOUGH THE UNCERTAINTY WITH THE ONSET OF
RAIN MAKES THE TEMPERATURE FORECAST CHALLENGING. EXCEPT IN THE
TRIAD...GUIDANCE HIGHS ARE RELATIVELY CLOSE...AND WILL PLAN TO GO
BETWEEN THERE. IF RAIN WOULD MOVE IN EARLIER...WOULD ALMOST
CERTAINLY LEAN TOWARD THE COOLER NAM BUT WITH SOME WRF GUIDANCE VOID
OF MUCH PRECIPITATION EVEN TO 18Z SUNDAY THINK AT LEAST A BLEND IS
WISE. IN TERMS OF THUNDER...BUFR SOUNDINGS PROVIDE FOR GREATEST
LAPSE RATES VERY LATE SUNDAY AFTERNOON THROUGH THE EVENING IN
ADVANCE OF A DRY SLOT WHICH BOTH THE NAM AND GFS BUFR SOUNDINGS
FORECAST MOVING IN FROM THE SOUTHWEST DURING THE NIGHT WITH
INCREASING 850MB SUBSIDENCE. 1000-500MB MUCAPE ON THE GFS IS LESS
THAN 200J/KG AND THE SHERBS3 IS LESS THAN ONE...BUT THE NAM IS
NOTICEABLY MORE UNSTABLE...ALTHOUGH IT IS DIFFICULT TO SEE SURFACE-
BASED CONCERNS ON THE NAM BUFR SOUNDINGS WITH A SLIGHT INVERSION
JUST OFF OF THE SURFACE. 0-3KM SHEAR AND HELICITY...AS EXPECTED...
ARE VERY HIGH AS WINDS JUST OFF OF THE SURFACE INCREASE GREATLY.
ADDED A SLIGHT CHANCE OF THUNDER DURING SUNDAY EVENING TO THE
FORECAST FOR THE INTERSTATE 95 CORRIDOR AS AT LEAST THERE IS A
SLIGHT CHANCE OF AT LEAST ELEVATED THUNDER...AND FOR THE HWO WILL
LIKELY ADD A MENTION OF AT LEAST WIND GUSTS TO 40MPH OR A LITTLE
HIGHER AS EVEN SHOWERS IN A RAPIDLY TIGHTENING SURFACE GRADIENT...
WITH 925MB WINDS APPROACHING 50KT...SHOULD RESULT IN A FEW QUITE
NOTICEABLE WIND GUSTS SIMPLY WITH PRECIPITATION. SPC HAS NOTED A
SLIGHT RISK OF SEVERE WEATHER WHERE THUNDER WILL BE ADDED TO THE
FORECAST AND WILL CERTAINLY NEED TO BE WATCHFUL OF INSTABILITY
TRENDS IN LATER FORECASTS...AS OTHER PARAMETERS ARE PLENTY HIGH
ENOUGH FOR ISOLATED SEVERE WEATHER. OVERNIGHT LOWS SUNDAY NIGHT NOT
MUCH DIFFERENT FROM THE HIGHS SUNDAY...STEADY TO RISING IN THE TRIAD
AND MAYBE A DIFFERENCE OF A DEGREE OR TWO ELSEWHERE IN GENERAL. -DJF
MONDAY AND MONDAY NIGHT...MID-LEVEL DRY AIR INTRUSION AND SUBSIDENCE
IN THE WAKE OF THE EXITING SHORTWAVE LIFTING OFF TO THE NORTH WILL
RESULT IN MOSTLY DRY CONDITIONS DURING THE DAY ON MONDAY. THE
TRAILING COLD FRONT WILL TRAVERSE THE AREA MONDAY EVENING/NIGHT BUT
AIRMASS IS JUST TOO DRY WITH LITTLE TO NO FORCING/LIFT ALOFT TO
SUPPORT POPS. TEMPERATURES MONDAY AFTERNOON IN THE PRE-FRONTAL WARM
SECTOR WILL WARM INTO THE UPPER 60S/NEAR 70 NW TO MID 70S SE. LOWS
MONDAY NIGHT WILL RANGE FROM LOWER 40S NW TO LOWER 50S SE AS CAA
SPREADS WEST TO EAST. -CBL
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 300 AM SATURDAY...
TUESDAY THROUGH WEDNESDAY: SOUTHERN STREAM TROUGH EMBEDDED AT THE
BASE OF THE AMPLIFYING LONG WAVE TROUGH WILL TRAVERSE THE GULF COAST
REGION ON TUESDAY AND THEN ACROSS THE SOUTHEAST ON WEDNESDAY. AFTER
A DRY START TO THE DAY ON TUESDAY...RAIN CHANCES WILL RETURN TUESDAY
EVENING/NIGHT AND INTO THE DAY ON WEDNESDAY AS WESTERN EDGE OF
DEEPER MOISTURE AXIS ATTENDANT TO OFFSHORE FRONTAL ZONE RETREATS
INLAND IN RESPONSE TO STRONG DPVA AND UPPER LEVEL DIVERGENCE WITHIN
THE RIGHT ENTRANCE REGION OF A 140-150KT JETSTREAK. BOTH THE GFS AND
EC CONTINUE TO TREND WETTER DURING THIS PERIOD WITH THE POTENTIAL
FOR CENTRAL AND EASTERN PORTIONS OF THE STATE TO RECEIVE SIGNIFICANT
RAINFALL. AS SUCH... WILL RAISE POPS TO CHANCE IN THE WEST TO LIKELY
IN THE EAST. NO P-TYPE ISSUES HERE WITH JUST A COLD RAIN FOR CENTRAL
NC. LOWS TUESDAY NIGHT IN THE MID/UPPER 30 NW TO LOWER 40S SE. HIGHS
WEDNESDAY IN THE 40S. PRECIP AND CLOUDS PULL OUT WEDNESDAY
EVENING/NIGHT WITH LOWS BACK DOWN INTO THE 30S.
THURSDAY AND FRIDAY: UNCERTAINTY REMAINS HIGH REGARDING THE APPROACH
OF THE NEXT BATCH OF SHORTWAVE ENERGY ROTATING EASTWARD WITHIN THE
BASE OF THE LONGWAVE TROUGH...WITH SOME GUIDANCE SUGGESTING A MID-
LEVEL SHORT WAVE MAY TRY TO CLOSE OFF OVER THE MID-ATLANTIC OR
CAROLINAS. ITS WORTH NOTING THAT NORTHERN STREAM SYSTEMS LIKE THIS
ARE OFTEN MOISTURE-STARVED... ESPECIALLY EAST OF THE MOUNTAINS.
GIVEN THERE HAS BEEN LITTLE CONTINUITY AMONG THE DETERMINISTIC
GUIDANCE ALONG WITH LARGE SPREAD AMONG THE ENSEMBLE MEMBERS...WILL
PLAY THE CONSERVATIVE APPROACH AND MAINTAIN A DRY FORECAST FOR
THURSDAY AND FRIDAY. IT LOOKS ALMOST CERTAIN HOWEVER THAT THIS
SYSTEM WILL DELIVER ANOTHER SHOT OF COLD ARCTIC AIR INTO THE
SOUTHEAST BY THE LATE WEEK AND INTO NEXT WEEKEND.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AS OF 705 AM SATURDAY...
FOR THE 12Z VALID TAF PERIOD...VFR CONDITIONS CONTINUE. LIGHT WINDS
THIS MORNING GRADUALLY VEER WITH A SLIGHT INCREASE IN WIND SPEEDS
AFTER SUNRISE...WITH SUSTAINED VALUES EXPECTED TO BE UNDER 10KT.
SURFACE WINDS UNDER HIGH PRESSURE BECOME LIGHT OR CALM AGAIN THIS
EVENING BACKING SLIGHTLY.
BEYOND THE 12Z VALID TAF PERIOD...CONDITIONS DETERIORATE SUNDAY AND
AS AREAS OF RAIN MOVE IN TO CENTRAL NORTH CAROLINA NUMEROUS AREAS OF
SUB-VFR...LIKELY IFR...CONDITIONS DEVELOP DURING THE DAY...
ESPECIALLY LATER IN THE DAY...CONTINUING AT LEAST INTO SUNDAY
EVENING. WINDS OFF OF THE SURFACE WILL ALSO INCREASE SUNDAY AND BY
SUNDAY NIGHT REACH OR EVEN EXCEED 50KT BY 2000FT WHICH COULD MAKE
LOW-LEVEL WIND SHEAR A PROBLEM BY LATE IN THE DAY INTO THE OVERNIGHT
HOURS. IMPROVING AVIATION CONDITIONS ARE POSSIBLE MONDAY AND WHILE
SOUTHWEST WINDS OFF THE SURFACE WILL NOT BE AS STRONG...A GUSTY
CHARACTER TO THE SURFACE WINDS CONTINUES. AS LOW PRESSURE MOVES
ALONG THE SOUTHEAST COAST TUESDAY INTO WEDNESDAY...UNCERTAINTY
INCREASES IN TERMS OF THE POTENTIAL FOR A RETURN TO A PERIOD OF SUB-
VFR CONDITIONS AND PRECIPITATION...ESPECIALLY EAST OF THE TRIAD. THE
NAM MODEL RETURNS THESE CONDITIONS MUCH FASTER TUESDAY...WHILE THE
GFS AND ECMWF ARE SLOWER...MORE OVERNIGHT TUESDAY INTO WEDNESDAY.
THE CURRENT THINKING IS TOWARD THE SLOWER SOLUTIONS.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF
SHORT TERM...DJF/CBL
LONG TERM...CBL
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1103 AM EST SAT NOV 22 2014
.SYNOPSIS...
FLOW BECOMES SOUTHWESTERLY TODAY...INCREASING SUNDAY FOR A WARMER
BUT WET WEEKEND. LOW PRESSURE BRINGS A WARM FRONT SUNDAY NIGHT...
FOLLOWED BY A COLD FRONT MONDAY WITH GOOD CHANCES FOR RAIN SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
11AM UPDATE...ALLOWED FREEZING RAIN ADVISORY TO EXPIRE AS TEMPS
ARE QUICKLY CLIMBING ABOVE FREEZING.
PREVIOUS DISCUSSION...
LATEST RADAR TRENDS HAVE A SLUG OF MOISTURE MOVING TOWARDS WV AND
TEMPS ARE STILL IN THE MID TEENS. HRRR HAS THE SLUG DRYING OUT
EXCEPT FOR PORTIONS OF SE OHIO...SO WENT WITH A FREEZING RAIN
ADVISORY FOR A BRIEF PERIOD WHERE PRECIP WILL BE FALLING INTO A
COLD AIR MASS. OBSERVATION IN PERRY COUNTY AT 27 SO OPTED TO LEAVE
THEM OUT AS THE WARM AIR EXTENDS TO ABOUT PERRY CNTY. AFTER 9 AM
TEMPS SHOULD WARM ABOVE FREEZING AND THE FZRA THREAT WILL BE
GONE.
THEN A PLEASANT DRY...DAY WHERE TEMPERATURES REBOUND TO NORMAL.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
AN APPROACHING LOW PRESSURE SYSTEM WILL LIFT FROM THE MISSISSIPPI
VALLEY...NORTH NORTHEAST INTO THE OH VALLEY AND WV SUNDAY AND
MONDAY. MODELS INDICATE WIND FLOW WILL TURN DEEP FROM THE SOUTH
SOUTHWEST...TO BRING MOIST AND WARM AIR MASS ON SUNDAY. A WARM
FRONT WILL MERGE FROM THIS FLOW TO PRODUCE AREAS OF RAIN SPREADING
FROM SOUTH TO NORTH.
WIND FLOW WILL INCREASE BY 00Z MONDAY...AS SUGGESTED BY H850 WINDS
FROM THE GFS/ECMWF OF ABOUT 65-70 KNOTS. UNDER ISENTROPIC
UP GLIDING...IT WILL BE MORE LIKELY FOR SOME OF THESE WINDS TO
CREATE GUSTY CONDITIONS OVER HIGHER ELEVATIONS.
AN ASSOCIATED COLD FRONT WILL CROSS WEST TO EAST EARLY MONDAY. WITH H850
TEMPERATURES AROUND 10C...EXPECT ALL PCPN TO FALL AS LIQUID.
THEREFORE...EXPECT ROUNDS OF SCATTERED TO NUMEROUS RAIN SHOWERS.
PW AROUND 1.25 INCHES AND STRONG DEEP LAYERED SHEAR COULD PRODUCE
A LOW CHANCE FOR THUNDER...BUT WILL KEEP MENTION OUT OF FORECAST.
COLDER AIR RUSHES IN BEHIND THE COLD FRONT DROPPING TO MINUS 6C BY
06 TUESDAY.
WENT CLOSE TO PREVIOUS TEMPERATURES...PERHAPS A LITTLE WARMER
SUNDAY INTO MONDAY DUE TO STRONG DEEP SOUTH SOUTHWESTERLY FLOW.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
SHOWERS WILL BEGIN TO END ON MONDAY NIGHT AS THE TROUGH WEAKENS AND
MOVES EAST. MODEL TRENDS HAVE WAFFLED A BIT WITH NEITHER THE GFS
AND ECMWF STAYING WITH A GREAT SOLUTION. SHORTWAVES ARE MORE
EVIDENT IN DEEPER TROUGH EXHIBITED BY THE ECMWF...BUT THE GFS
CURRENTLY SHOWS A MORE WESTERN FLOW. TOOK A BLEND OF THE TWO MODELS
TO RESOLVE SOME OF THE DISAGREEMENT IN THE HOPES THE SOLUTIONS WILL
CONVERGE AS WE MOVE CLOSER IN TIME.
TEMPERATURES WILL COOL SIGNIFICANTLY BY TUESDAY WITH THE PASSAGE OF
A COLD FRONT. THESE COOLER TEMPERATURES COMBINED WITH LOW PRESSURE
MOVING EAST FROM THE GREAT LAKES WILL PROVIDE SOME OPPORTUNITY FOR
SOME SNOW SHOWERS ALONG THE OHIO RIVER EARLY
THURSDAY...TRANSITIONING TO RAIN BY AFTERNOON FOR THE LOWLANDS. THE
MOUNTAINS WILL CONTINUE TO HAVE A SLIGHT CHANCE OF SOME SNOW SHOWERS
THROUGH THE NIGHT.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
QUIET VFR WEATHER. A BRIEF PERIOD OF FREEZING RAIN IS POSSIBLE IN
INTERIOR SE OHIO SAT MORNING.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SUNDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: LOW CHANCE OF MVFR CIGS ACROSS INTERIOR SE OHIO
SAT MORNING AND THE NRN WV MOUNTAINS SAT MIDDAY AND AFTERNOON.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EST 1HRLY 09 10 11 12 13 14 15 16 17 18 19 20
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z SUNDAY...
IFR POSSIBLE ON EASTERN MOUNTAIN SLOPES AND ACROSS THE MIDDLE OHIO
VALLEY IN RAIN AND STRATUS LATE SUN INTO MON MORNING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/JW
NEAR TERM...MZ/JW
SHORT TERM...ARJ
LONG TERM...LS
AVIATION...JW
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
828 AM EST SAT NOV 22 2014
.SYNOPSIS...
FLOW BECOMES SOUTHWESTERLY TODAY...INCREASING SUNDAY FOR A WARMER
BUT WET WEEKEND. LOW PRESSURE BRINGS A WARM FRONT SUNDAY NIGHT...
FOLLOWED BY A COLD FRONT MONDAY WITH GOOD CHANCES FOR RAIN SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
820 AM UPDATE...WARM ADVECTION A BIT SLOWER TO PICK UP THAN
PREVIOUSLY THOUGHT...SO LOWERED TEMPS FOR THE NEXT COUPLE HOURS.
THIS ALSO PROMPTED AN EXTENSION OF THE FREEZING RAIN ADVISORY
UNTIL 11 AM. HAVE RECEIVED A COUPLE CALLS FROM MORGAN COUNTY OHIO OF
FREEZING RAIN WITH ICE ON ROADS.
PREVIOUS DISCUSSION...
LATEST RADAR TRENDS HAVE A SLUG OF MOISTURE MOVING TOWARDS WV AND
TEMPS ARE STILL IN THE MID TEENS. HRRR HAS THE SLUG DRYING OUT
EXCEPT FOR PORTIONS OF SE OHIO...SO WENT WITH A FREEZING RAIN
ADVISORY FOR A BRIEF PERIOD WHERE PRECIP WILL BE FALLING INTO A
COLD AIR MASS. OBSERVATION IN PERRY COUNTY AT 27 SO OPTED TO LEAVE
THEM OUT AS THE WARM AIR EXTENDS TO ABOUT PERRY CNTY. AFTER 9 AM
TEMPS SHOULD WARM ABOVE FREEZING AND THE FZRA THREAT WILL BE
GONE.
THEN A PLEASANT DRY...DAY WHERE TEMPERATURES REBOUND TO NORMAL.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
AN APPROACHING LOW PRESSURE SYSTEM WILL LIFT FROM THE MISSISSIPPI
VALLEY...NORTH NORTHEAST INTO THE OH VALLEY AND WV SUNDAY AND
MONDAY. MODELS INDICATE WIND FLOW WILL TURN DEEP FROM THE SOUTH
SOUTHWEST...TO BRING MOIST AND WARM AIR MASS ON SUNDAY. A WARM
FRONT WILL MERGE FROM THIS FLOW TO PRODUCE AREAS OF RAIN SPREADING
FROM SOUTH TO NORTH.
WIND FLOW WILL INCREASE BY 00Z MONDAY...AS SUGGESTED BY H850 WINDS
FROM THE GFS/ECMWF OF ABOUT 65-70 KNOTS. UNDER ISENTROPIC
UP GLIDING...IT WILL BE MORE LIKELY FOR SOME OF THESE WINDS TO
CREATE GUSTY CONDITIONS OVER HIGHER ELEVATIONS.
AN ASSOCIATED COLD FRONT WILL CROSS WEST TO EAST EARLY MONDAY. WITH H850
TEMPERATURES AROUND 10C...EXPECT ALL PCPN TO FALL AS LIQUID.
THEREFORE...EXPECT ROUNDS OF SCATTERED TO NUMEROUS RAIN SHOWERS.
PW AROUND 1.25 INCHES AND STRONG DEEP LAYERED SHEAR COULD PRODUCE
A LOW CHANCE FOR THUNDER...BUT WILL KEEP MENTION OUT OF FORECAST.
COLDER AIR RUSHES IN BEHIND THE COLD FRONT DROPPING TO MINUS 6C BY
06 TUESDAY.
WENT CLOSE TO PREVIOUS TEMPERATURES...PERHAPS A LITTLE WARMER
SUNDAY INTO MONDAY DUE TO STRONG DEEP SOUTH SOUTHWESTERLY FLOW.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
SHOWERS WILL BEGIN TO END ON MONDAY NIGHT AS THE TROUGH WEAKENS AND
MOVES EAST. MODEL TRENDS HAVE WAFFLED A BIT WITH NEITHER THE GFS
AND ECMWF STAYING WITH A GREAT SOLUTION. SHORTWAVES ARE MORE
EVIDENT IN DEEPER TROUGH EXHIBITED BY THE ECMWF...BUT THE GFS
CURRENTLY SHOWS A MORE WESTERN FLOW. TOOK A BLEND OF THE TWO MODELS
TO RESOLVE SOME OF THE DISAGREEMENT IN THE HOPES THE SOLUTIONS WILL
CONVERGE AS WE MOVE CLOSER IN TIME.
TEMPERATURES WILL COOL SIGNIFICANTLY BY TUESDAY WITH THE PASSAGE OF
A COLD FRONT. THESE COOLER TEMPERATURES COMBINED WITH LOW PRESSURE
MOVING EAST FROM THE GREAT LAKES WILL PROVIDE SOME OPPORTUNITY FOR
SOME SNOW SHOWERS ALONG THE OHIO RIVER EARLY
THURSDAY...TRANSITIONING TO RAIN BY AFTERNOON FOR THE LOWLANDS. THE
MOUNTAINS WILL CONTINUE TO HAVE A SLIGHT CHANCE OF SOME SNOW SHOWERS
THROUGH THE NIGHT.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
QUIET VFR WEATHER. A BRIEF PERIOD OF FREEZING RAIN IS POSSIBLE IN
INTERIOR SE OHIO SAT MORNING.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SUNDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: LOW CHANCE OF MVFR CIGS ACROSS INTERIOR SE OHIO
SAT MORNING AND THE NRN WV MOUNTAINS SAT MIDDAY AND AFTERNOON.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EST 1HRLY 09 10 11 12 13 14 15 16 17 18 19 20
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z SUNDAY...
IFR POSSIBLE ON EASTERN MOUNTAIN SLOPES AND ACROSS THE MIDDLE OHIO
VALLEY IN RAIN AND STRATUS LATE SUN INTO MON MORNING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FREEZING RAIN ADVISORY UNTIL 11 AM EST THIS MORNING FOR WVZ009.
OH...FREEZING RAIN ADVISORY UNTIL 11 AM EST THIS MORNING FOR OHZ066-
067-075-076-083>086.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/JW
NEAR TERM...MZ/JW
SHORT TERM...ARJ
LONG TERM...LS
AVIATION...JW
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
648 AM EST SAT NOV 22 2014
.SYNOPSIS...
FLOW BECOMES SOUTHWESTERLY TODAY...INCREASING SUNDAY FOR A WARMER
BUT WET WEEKEND. LOW PRESSURE BRINGS A WARM FRONT SUNDAY NIGHT...
FOLLOWED BY A COLD FRONT MONDAY WITH GOOD CHANCES FOR RAIN SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
ADDED PERRY COUNTY UNDER FREEZING RAIN ADVISORY UNTIL 9 AM.
LATEST RADAR TRENDS HAVE A SLUG OF MOISTURE MOVING TOWARDS WV AND
TEMPS ARE STILL IN THE MID TEENS. HRRR HAS THE SLUG DRYING OUT
EXCEPT FOR PORTIONS OF SE OHIO...SO WENT WITH A FREEZING RAIN
ADVISORY FOR A BRIEF PERIOD WHERE PRECIP WILL BE FALLING INTO A
COLD AIR MASS. OBSERVATION IN PERRY COUNTY AT 27 SO OPTED TO LEAVE
THEM OUT AS THE WARM AIR EXTENDS TO ABOUT PERRY CNTY. AFTER 9 AM
TEMPS SHOULD WARM ABOVE FREEZING AND THE FZRA THREAT WILL BE
GONE.
THEN A PLEASANT DRY...DAY WHERE TEMPERATURES REBOUND TO NORMAL.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
AN APPROACHING LOW PRESSURE SYSTEM WILL LIFT FROM THE MISSISSIPPI
VALLEY...NORTH NORTHEAST INTO THE OH VALLEY AND WV SUNDAY AND
MONDAY. MODELS INDICATE WIND FLOW WILL TURN DEEP FROM THE SOUTH
SOUTHWEST...TO BRING MOIST AND WARM AIR MASS ON SUNDAY. A WARM
FRONT WILL MERGE FROM THIS FLOW TO PRODUCE AREAS OF RAIN SPREADING
FROM SOUTH TO NORTH.
WIND FLOW WILL INCREASE BY 00Z MONDAY...AS SUGGESTED BY H850 WINDS
FROM THE GFS/ECMWF OF ABOUT 65-70 KNOTS. UNDER ISENTROPIC
UP GLIDING...IT WILL BE MORE LIKELY FOR SOME OF THESE WINDS TO
CREATE GUSTY CONDITIONS OVER HIGHER ELEVATIONS.
AN ASSOCIATED COLD FRONT WILL CROSS WEST TO EAST EARLY MONDAY. WITH H850
TEMPERATURES AROUND 10C...EXPECT ALL PCPN TO FALL AS LIQUID.
THEREFORE...EXPECT ROUNDS OF SCATTERED TO NUMEROUS RAIN SHOWERS.
PW AROUND 1.25 INCHES AND STRONG DEEP LAYERED SHEAR COULD PRODUCE
A LOW CHANCE FOR THUNDER...BUT WILL KEEP MENTION OUT OF FORECAST.
COLDER AIR RUSHES IN BEHIND THE COLD FRONT DROPPING TO MINUS 6C BY
06 TUESDAY.
WENT CLOSE TO PREVIOUS TEMPERATURES...PERHAPS A LITTLE WARMER
SUNDAY INTO MONDAY DUE TO STRONG DEEP SOUTH SOUTHWESTERLY FLOW.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
SHOWERS WILL BEGIN TO END ON MONDAY NIGHT AS THE TROUGH WEAKENS AND
MOVES EAST. MODEL TRENDS HAVE WAFFLED A BIT WITH NEITHER THE GFS
AND ECMWF STAYING WITH A GREAT SOLUTION. SHORTWAVES ARE MORE
EVIDENT IN DEEPER TROUGH EXHIBITED BY THE ECMWF...BUT THE GFS
CURRENTLY SHOWS A MORE WESTERN FLOW. TOOK A BLEND OF THE TWO MODELS
TO RESOLVE SOME OF THE DISAGREEMENT IN THE HOPES THE SOLUTIONS WILL
CONVERGE AS WE MOVE CLOSER IN TIME.
TEMPERATURES WILL COOL SIGNIFICANTLY BY TUESDAY WITH THE PASSAGE OF
A COLD FRONT. THESE COOLER TEMPERATURES COMBINED WITH LOW PRESSURE
MOVING EAST FROM THE GREAT LAKES WILL PROVIDE SOME OPPORTUNITY FOR
SOME SNOW SHOWERS ALONG THE OHIO RIVER EARLY
THURSDAY...TRANSITIONING TO RAIN BY AFTERNOON FOR THE LOWLANDS. THE
MOUNTAINS WILL CONTINUE TO HAVE A SLIGHT CHANCE OF SOME SNOW SHOWERS
THROUGH THE NIGHT.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
QUIET VFR WEATHER. A BRIEF PERIOD OF FREEZING RAIN IS POSSIBLE IN
INTERIOR SE OHIO SAT MORNING.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SUNDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: LOW CHANCE OF MVFR CIGS ACROSS INTERIOR SE OHIO
SAT MORNING AND THE NRN WV MOUNTAINS SAT MIDDAY AND AFTERNOON.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22
EST 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z SUNDAY...
IFR POSSIBLE ON EASTERN MOUNTAIN SLOPES AND ACROSS THE MIDDLE OHIO
VALLEY IN RAIN AND STRATUS LATE SUN INTO MON MORNING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR WVZ009.
OH...FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR OHZ066-
067-075-076-083>086.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/JW
NEAR TERM...JW
SHORT TERM...ARJ
LONG TERM...LS
AVIATION...JW
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
419 AM CST SAT NOV 22 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM CST SAT NOV 22 2014
FOG AND STRATUS SHOULD PERSIST FROM NW IA INTO PART OF SW MN
INTO THE LATE MORNING WHEN LOW LEVEL SWRLY FLOW AND SOME
WARMING WILL BE SWEEPING IT OUT. FOG WILL CONTINUE TO GET
MARGINALLY DENSE IN SOME AREAS BUT WIDESPREAD DENSE FOG HAD NOT
DEVELOPED...AND WITH A CONTINUING DECENT LOW LEVEL FLOW IN THAT AREA
SUSPECT WE WILL NOT NEED A DENSE FOG ADVISORY...BUT OF COURSE WILL
MONITOR NEXT FEW HOURS. SOME VERY PATCHY SHALLOW FOG WILL
CONTINUE TO DEVELOP FURTHER WEST BUT DRIER AIR NOT MUCH ABOVE THE
SURFACE SHOULD PREVENT MUCH. ASIDE FROM SOME STRATUS LINGERING
FAR EAST INTO PERHAPS THE EARLY AFTERNOON...THE FORECAST AREA IS
EXPECTED TO BE MOSTLY SUNNY TODAY. TEMPERATURES OF COURSE WILL BE
MILD WITH A DECENT ROUND OF SNOWMELT. UPPER 30S NORTHEAST TO THE
LOWER 50S SOUTHWEST LOOKS GOOD FOR HIGHS.
TONIGHT WE EXPECT THAT THE STRATUS WILL REDEVELOP SOUTHEAST AS
HIGHER CLOUDS BEGIN TO INCREASE FROM THE WEST WITH APPROACHING
SYSTEM. THERE SEEMS TO BE ENOUGH MID LEVEL LIFT FOR A FEW LIGHT
SHOWERS TO SPREAD IN FROM THE WEST BUT MODELS ARE SHOWING FAIRLY DRY
AND WILL CONTINUE TO PLAY THE AIR BEING DRY ENOUGH TO PRECLUDE
PRECIPITATION THIS WAY THROUGH THE NIGHTTIME HOURS. THE INCREASE IN
LOW CLOUDS AND THEIR DEPTH OVER NORTHWEST IOWA SUGGESTS SOME DRIZZLE
POSSIBLE LATE TONIGHT...BUT THAT INCREASED DEPTH ALSO SUGGESTS
DROPLETS COULD BE BIG ENOUGH FOR MINIMALLY MEASURABLE LIGHT
RAIN...AND SINCE WE HAVE BEEN CARRYING LOW POPS...WILL CONTINUE
THEM FOR LATE TONIGHT...EVEN THOUGH MID LEVEL SUPPORT FOR RAIN
SEEMS FURTHER SOUTHEAST. TEMPERATURES WILL BE MILD WITH AREAS IN
SOUTHEAST SD NORTH OF INTERSTATE 90 MAYBE COOLING A DEGREE OR TWO
BELOW FREEZING. UNSURE OF THE DEGREE OF LATE NIGHT MIXING WITH
APPROACHING SYSTEM SO WILL NOT GET CUTE WITH ANY SUDDEN TEMPERATURE
JUMPS...BUT THEY COULD HAPPEN.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 415 AM CST SAT NOV 22 2014
DOMINANT FOCUS OF THE START OF THE LONGER TERM IS EVOLUTION OF THE
STRONG SYSTEM TO THE EAST HEADING INTO SUNDAY NIGHT AND MONDAY. AS
THE NORTHERN STREAM ENERGY COMPONENT APPROACHES ON SUNDAY...AT
LEAST A MINIMAL THREAT FOR SOME EARLY DAY PRECIPITATION AS VARIOUS
DEGREE OF SHARPNESS TO TROUGH BEGINS TO SLIDE ACROSS THE DAKOTAS.
IF NOT FOR A FEW MODELS/RUNS INDICATING THE MID LEVEL FRONTAL ZONE
ACTUALLY UNDERGOING WEAKENING HEADING ACROSS THE CWA DURING THE
MORNING...WOULD JUSTIFY PERHAPS STRONGER ON THE POPS FOR THE MORNING
AND EARLY AFTERNOON. THERE IS A BIT OF CONCERN ON PRECIPITATION
TYPE POTENTIAL WITH FAIRLY WARM TEMPS ALOFT BATTLING WHAT IS
CERTAIN TO BE A FAIRLY DECENT WET BULB IMPACT. PROBABLY A MIX OF
RAIN OR SNOW...OR EVEN ALL LIGHT SNOW IF CAN GET A BIT MORE
INTENSE OR BANDED PER NAM TYPE SOLUTION. FURTHER SOUTHEAST...
AHEAD OF THE LOW LEVEL WIND SHIFT...WILL LIKELY FIND A MURKY MESS
OF LOWER CLOUDS...SOME FOG...AND CHANCE OF DRIZZLE/LIGHT RAIN IN
THE EARLY MORNING. THIS WILL GET QUICKLY SHOVED ASIDE BY SHIFT IN
WINDS TO THE NORTHWEST. INITIALLY NOT A VERY STRONG COLD PUSH...
WHICH SHOULD ALLOW TEMPS TO RETURN TO THE LOWER 40S ACROSS THE
SOUTHEAST HALF. HOWEVER...COLDER AIR WILL REALLY START TO SURGE
INTO THE AREA DURING THE AFTERNOON...WITH A 6-8C DROP IN 925 HPA
TEMPS LIMITING MIXING BY MIDDAY NORTHWEST...MID AFTERNOON CENTRAL...
AND LATE DAY SOUTHEAST CWA...AND MOST CERTAINLY ENDING WITH A MORE
THAN TYPICAL LATE DAY DROP. WINDS WILL ALSO INCREASE TO 20 TO 30
MPH BY LATE DAY OVER MUCH OF SE SD.
OVERNIGHT IS WHEN THE MERGING OF THE SOUTHERN STREAM AND NORTHERN
STREAM ENERGY OCCURS...BUT WILL BE TO THE EAST...AND IMPACT WILL
BE MAINLY TO THE WIND FIELDS ACROSS THE AREA. GFS IS FAR STRONGER
WITH CYCLOGENESIS...SOMEWHAT FURTHER EASTWARD. WHATEVER SOLUTION
IS MORE CORRECT IN THE END...OUR AREA IS SURE TO EXPERIENCE VERY
STRONG AND GUSTY WINDS FROM 25 TO 45 MPH...AND A TENDENCY FOR THE
SUNDAY NIGHT INTO MONDAY PERIOD FOR SOME LIGHTER SNOWFALL TO CYCLE
SOUTHEASTWARD ACROSS THE AREA...ESPECIALLY SW MN. APPEARS THAT
TOTALS WILL CERTAINLY BE LIGHT AS DEEPER FORCING CONTINUES TO THE
EAST...BUT COULD SEE SOME HALF INCH OR BIT MORE AMOUNTS ACROSS
SOUTHWEST MINNESOTA BY THE TIME IT ENDS ON MONDAY EVENING.
DESPITE THE WINDS...DO NOT EXPECT ENOUGH NEW SNOWFALL TO CREATE
ANY BLOWING SNOW ISSUES...AND THE OLDER SNOW WILL BE WELL CRUSTED
FROM WARMING ABOVE FREEZING FOR A COUPLE DAYS.
FOR THE CRITICAL THANKSGIVING TRAVEL TIME...BY TUESDAY AND
WEDNESDAY...THE AGREEMENT IN THE LONGER WAVE PATTERN IS THERE IN
A GENERAL SENSE...BUT THE IMPORTANT DETAILS ARE VASTLY DIFFERENT.
MOST SOLUTIONS INDICATE A FAIRLY DISTINCT CLIPPER SYSTEM MOVING
FROM NORTH DAKOTA TOWARD CENTRAL MINNESOTA...BUT GFS IS ABOUT 6-9
HOURS QUICKER THAN EC/CANADIAN. TUESDAY WILL PUT CWA INTO A WARMER
SECTOR OF WAVE...AND WILL LIKELY SEE TEMPS PUSH INTO THE 35 TO 40
DEGREE RANGE OVER THE SOUTHWEST HALF OF THE AREA. HAVE PUSHED UP
TIMING FOR A BURST OF SNOWFALL WITHIN THE WARM AIR ADVECTION ZONE
TUESDAY NIGHT... BUT WITH THE STRONGER AND DEEPER FORCING
REMAINING JUST NORTHEAST OF THE AREA...HAVE KEPT THINGS AS A
CHANCE POP FOR THE TIME. THIS IS WHERE THINGS START TO DIVERGE
SIGNIFICANTLY...WITH EC SO AMPLIFIED WITH THIS CLIPPER WAVE THAT
THE THERMAL BOUNDARY IS DRIVEN SO FAR SOUTHWARD THAT ARCTIC RIDGE
TAKES OVER AND IS SIMPLY COLD AND DRY THROUGH THE END OF THE WEEK.
THE GFS/CANADIAN ARE NOT AS AMPLIFIED...GFS LEAST SO...AND THEN
FIND APPROACH OF THE NEXT SUBTLE NORTHERN STREAM WAVE IN A
FAVORABLE LOCATION TO INTERACT WITH THERMAL RIBBON...RESULTING IN
A BAND OF LIGHT PRECIPITATION ACROSS THE AREA...EITHER MAINLY
NORTH PER 00Z GFS...OR THROUGH THE HEART PER 06Z GFS...OR THE
MISSOURI VALLEY PER CANADIAN. QPF/SNOW RATIOS OF 18-20/1 WOULD
BRING PERHAPS 1 TO 3 INCHES OF SNOWFALL IN A WORST CASE AT THIS
POINT. COULD NOT GET A REGIONAL CONSENSUS ON INTRODUCING POPS WITH
INITIALIZATION GRIDS SUB MEASURABLE FOR MOST ON WEDNESDAY INTO
WEDNESDAY EVENING...SO HAVE DEFERRED TO LATER FORECASTS IN HOPES
GUIDANCE CONVERGES ENOUGH TO SUPPORT MORE REASONABLE POPS. ARCTIC
HIGH SETTLES SOUTHWARD THROUGH THANKSGIVING TO GIVE TEMPS WELL
BELOW NORMAL ONCE AGAIN...WITH A LITTLE RECOVERY EXPECTED FRIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY EVENING)
ISSUED AT 1052 PM CST FRI NOV 21 2014
FORECAST CONTINUES TO REMAIN A CHALLENGE TONIGHT INTO TOMORROW.
PRETTY CONFIDENT KHON REMAINS VFR...BUT STRATUS AND FOG CONCERNS
REMAIN EAST OF THE JAMES RIVER. WATCHING LARGE AREA OF LOW STRATUS
CONTINUE TO PUSH NORTH TOWARDS THE REGION...WITH MVFR CIGS INTO
KSUX. BASED ON MODEL SOUNDINGS AND UPSTREAM OBS...THINK THEY WILL
EVENTUALLY GET CIGS BELOW 500 FEET...AND COULD POSSIBLY ALSO SEE
DENSE FOG. LESS CERTAIN ABOUT KFSD...WHICH WILL LIKELY BE NEAR THE
WEST EDGE OF ANY STRATUS AND FOG. BASED ON THE LATEST RAP AND HRRR
WILL KEEP IFR CIGS INTO KFSD LATER TONIGHT...ALTHOUGH AGAIN
CONFIDENCE IS LOW. WHAT IS ALSO UNCERTAIN IS HOW QUICKLY THE STRATUS
AND FOG EXITS TOMORROW. STAYED ON THE OPTIMISTIC SIDE FOR NOW GIVEN
LOW CONFIDENCE...BUT WOULD NOT BE SURPRISED IF LOW CIGS AND VIS
STICK AROUND LONGER THAN CURRENTLY FORECAST...AS WINDS WILL STAY OUT
OF THE SOUTH SOUTHEAST THROUGH THE DAY.
SO IN SUMMARY...AT THE LEAST THINK NORTHWEST IOWA AND PORTIONS OF
SOUTHWEST MINNESOTA WILL SEE LOW STRATUS AND POTENTIALLY DENSE FOG
TONIGHT INTO EARLY TOMORROW. THIS COULD EXTEND AS FAR WEST AS THE
INTERSTATE 29 CORRIDOR. FOR NOW HAVE IMPROVEMENTS BY MID
MORNING...BUT THE POSSIBILITY IS DEFINITELY THERE THAT THESE
CONDITIONS LINGER INTO LATE MORNING OR EVEN EARLY AFTERNOON...WITH
CONDITIONS SLOWLY IMPROVING TO VFR FROM WEST TO EAST.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...
LONG TERM...CHAPMAN
AVIATION...CHENARD
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
933 AM CST SAT NOV 22 2014
.UPDATE...
LATEST RADAR IMAGERY SHOWS A FEW LIGHT RAIN SHOWERS AND SPRINKLES
CONTINUE ACROSS NORTHWEST PARTS OF THE MID STATE. HRRR INDICATES
THIS ACTIVITY WILL CONTINUE THROUGH AROUND 18Z...SO EXPANDED
SLIGHT CHANCE POPS A BIT EASTWARD AND EXTENDED THROUGH THAT TIME.
PRECIP SHOULD MOVE OUT BY AFTERNOON WITH PARTLY CLOUDY SKIES AND
MUCH WARMER TEMPERATURES WITH HIGHS IN THE LOWER 60S. REST OF
FORECAST LOOKS GOOD AND ONLY MINOR TWEAKS WERE MADE.
SHAMBURGER
&&
.PREV DISCUSSION... /ISSUED 537 AM CST SAT NOV 22 2014/
UPDATE...FOR 12Z AVIATION FORECASTS.
AVIATION...
A FEW MORNING SPRINKLES IN NORTHWEST COUNTIES/CKV...OTHERWISE NO
PRECIPITATION TODAY. EXTENSIVE MID AND HIGH CLOUDS WILL CONTINUE
STREAMING ACROSS MIDDLE TN AHEAD OF A UPPER LEVEL STORM SYSTEM
THAT WILL APPROACH LATE TONIGHT AND SUNDAY. SFC WINDS WILL PICK UP
A LITTLE TODAY AS GRADIENTS TIGHTEN.
INCREASING MOISTURE WILL HELP DEVELOP LOW CLOUDS AFTER 00Z TONIGHT.
MVFR CIGS POSSIBLE AT BNA AND CKV TOWARD 12Z SUNDAY. HIGH CHANCE OF
RAIN AND MVFR/IFR CIGS SHORTLY AFTER THIS FORECAST CYCLE ENDS AT
12Z SUNDAY.
PREV DISCUSSION... /ISSUED 416 AM CST SAT NOV 22 2014/
DISCUSSION...
THE SURFACE RIDGE THAT HAS KEPT US DRY ACROSS THE MID-STATE THE LAST
COUPLE OF DAYS HAS MOVED OFF TO THE EAST. NOW SITTING OVER THE
MID-ATLANTIC STATES...IT HAS PUT THE SOUTHEAST U.S. INTO A
SOUTHEASTERLY BOUNDARY LAYER FLOW. COUPLED WITH A WEAK MID-LEVEL
DISTURBANCE MOVING ENE THROUGH THE MID-MISSISSIPPI/TN/OHIO
VALLEYS...THERE ARE A FEW SHOWERS ON THE RADAR. THE CATCH IS...IT`S
BEEN SO DRY AND THE ATMOSPHERE IS TAKING SO LONG TO SATURATE THAT
NOT MUCH OF THIS RAIN IS REACHING THE GROUND. KCKV SHOWED LIGHT
RAIN A COUPLE OF HOURS AGO...BUT THEY ONLY MEASURED A TRACE. THESE
RADAR REFLECTIVITIES SHOULD MOVE OFF TO THE NE THROUGH THE MORNING
HOURS...LEAVING PARTLY TO MOSTLY CLOUDY CONDITIONS ACROSS THE
STATE. THE MOST INTERESTING PART OF THE DAY WILL BE THE WINDS AS
THE PRESSURE GRADIENT TIGHTENS ACROSS MIDDLE TN. IT WILL BE BREEZY
AND MOST EVERYONE WILL WARM INTO THE 60S TODAY WITH MIDDLE TO UPPER
50S ON THE PLATEAU.
ALREADY IN ITS BEGINNING STAGES...AN INTENSE SHORTWAVE TROUGH IS
EXPECTED TO DEVELOP OVER THE DESERT SOUTHWEST TODAY. THIS SYSTEM
WILL BE OUR WEATHER MAKER ON SUNDAY. IN RESPONSE TO THIS SYSTEM
ROUNDING THE BASE OF THE LONGWAVE PATTERN...A SURFACE LOW WILL
DEVELOP OVER E TEXAS TONIGHT...MOVING NEWD...AND PASSING JUST TO THE
WEST OF US. UNFORTUNATELY...THIS PUTS US IN A PRECARIOUS POSITION.
THE UPPER LEVEL TROUGH SWINGS INTO A NEGATIVE TILT SUNDAY MORNING
AND BECAUSE OF THIS...THE SURFACE LOW DEEPENS PRETTY RAPIDLY. THIS
WILL RESULT IN A COUPLE OF THINGS...FIRST...IT WILL BE WINDY
SUNDAY. WHILE TODAY`S BREEZY CONDITIONS WILL RELAX A BIT TONIGHT...
THE SURFACE PRESSURE GRADIENT TIGHTENS BACK UP SIGNIFICANTLY AND WE
COULD SEE SUSTAINED WINDS OF 15-25 MPH WITH GUSTS TO 35 OR 40 MPH
ON SUNDAY. THIS WILL PUT US ON THE BRINK OF A WIND ADVISORY...
BUT THIS LIKELY WON`T BE ISSUED UNTIL LATER TODAY OR EVEN TONIGHT.
A SECOND RESULT OF THE QUICK INTENSIFICATION OF THIS SYSTEM IS THE
AMOUNT OF WIND SHEAR THAT WILL ENSUE. DEEP LAYER SHEAR OF 50-70
KTS IS LIKELY AND 0-3KM SRH VALUES OF 800-1000 M^2/S^2 MAY ALSO
OCCUR. THIS AMOUNT OF WIND SHEAR MIGHT ACTUALLY BE OUR SAVING
GRACE. BECAUSE OF THE SOUTHEAST BOUNDARY LAYER FLOW OVER THE NEXT
24-36 HOURS...RETURN MOISTURE SHOULD BE FAIRLY MODERATE AHEAD OF
THIS SYSTEM THIS FAR NORTH. IN FACT...THE 60 DEGREE DEW POINT LINE
SHOULD REMAIN SOUTH OF US. WITH SO MUCH WIND SHEAR AND RELATIVELY
LITTLE INSTABILITY...WE SHOULD REMAIN NORTH OF ANY WIDESPREAD
SEVERE WEATHER THREAT. WHAT WILL BE OF CONCERN IS THE 850MB JET
THAT IS PROGGED TO DEVELOP SUNDAY MORNING THAT COULD BE AS STRONG
AS 50 TO 75 KTS. THIS MEANS WE CAN`T RULE OUT THE POTENTIAL FOR AN
ISOLATED STRAIGHT LINE WIND THREAT WITH ANY THUNDERSTORMS THAT
DEVELOP. I WILL GO AHEAD AND HIGHLIGHT THIS ISOLATED WIND THREAT
IN THE HAZARDOUS WEATHER OUTLOOK THIS MORNING FOR SUNDAY...BUT
THIS SHOULD NOT BE A WIDESPREAD SEVERE WEATHER EVENT.
FROPA WILL BE A LITTLE DELAYED WITH THIS SYSTEM...OCCURRING THROUGH
THE MORNING HOURS ON MONDAY. SOME LIGHT RAIN MAY RESULT...BUT THE
BULK OF THE ACTIVITY SHOULD BE ON SUNDAY.
BELOW NORMAL TEMPERATURES WILL RETURN FOR THE REMAINDER OF THE
WEEK. DAYTIME HIGHS IN THE 40S ARE EXPECTED BY TUESDAY...WITH
OVERNIGHT LOWS IN THE 20S AND 30S...BUT WE SHOULD REMAIN DRY
THROUGHOUT THE WEEK.
UNGER
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
55
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
906 AM CST SAT NOV 22 2014
.UPDATE...
WATER VAPOR IMAGERY SHOWED AN AREA OF LIFT IN AN UPPER LEVEL
DIFFLUENT AREA MOVING OUT OF EXTREME SOUTHEASTERN NEW MEXICO INTO
THE SOUTHWESTERN SOUTH PLAINS. THIS LIFT WAS RESULTING IN SOME
THUNDERSTORM ACTIVITY WHERE SHORT TERM MODELS CURRENTLY SHOW NO
DEVELOPMENT. POPS HAVE BEEN RAISED FOR THE REMAINDER OF THE
MORNING IN ANTICIPATION FOR THIS ACTIVITY TO AFFECT THE SOUTHERN
SOUTH PLAINS. THIS LIFT IS THEN EXPECTED TO QUICKLY MOVE EAST THIS
AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 524 AM CST SAT NOV 22 2014/
AVIATION...
VLIFR FOG AND LIFR CLOUD DECKS HAVE DEVELOPED AT KCDS THIS
MORNING...WITH KLBB VIS DROPPING BELOW 10 SM AND FEW DECKS BELOW
2000 FT AGL. WILL EXPECT KLBB TO FURTHER DETERIORATE LATER THIS
MORNING TO MVFR FOG AND IFR DECKS. CONDITIONS WILL IMPROVE TO VFR
CATEGORY BY MID-MORNING. LIGHT AND VARIABLE WINDS WILL VEER TO THE
WEST SOUTHWEST THIS AFTN AND BECOME SLIGHTLY BREEZY TOWARDS THE
END OF TAF PERIOD.
PREV DISCUSSION... /ISSUED 214 AM CST SAT NOV 22 2014/
SHORT TERM...
MAIN FOCUS FOR THE SHORT TERM PERIOD CONTINUES TO BE THE UA LOW
DIGGING ESE ACROSS NWRN OLD MEXICO EARLY THIS MORNING...WHICH WILL
AID TO INCREASE PRECIP CHANCES LATER THIS MORNING.
AN AREA OF STRATUS AND FOGGY CONDITIONS ONCE AGAIN DEVELOPED ACROSS
ERN TEXAS AND OKLAHOMA PER 08Z METARS...THUS COINCIDING WITH THE
BEST SFC MOISTURE /DEWPOINTS IN THE 50S AND 60S/. LOW CLOUDS AND FOG
HAVE IMPACTED THE FAR SERN TX PANHANDLE...WHICH IS NOT SURPRISING
GIVEN A LOW TEMP-DEWPOINT SPREAD. THE HRRR SOLUTION HANDLED THE
EVOLUTION OF THE LOW CLOUDS AND FOG QUITE WELL YESTERDAY...AND SINCE
IT SHOWS A CONTINUAL WESTWARD DEVELOPMENT FOR THE NEXT SEVERAL HOURS
UNTIL MID-MORNING WHERE THEREAFTER CONDITIONS WILL IMPROVE...THIS
FORECAST PACKAGE WILL REFLECT THAT PROGRESSION.
AS PREVIOUSLY STATED...THE BEST MOISTURE AXIS WAS NOTED EAST OF THE
FA AND WITH THE AID OF A BIT OF UL SUPPORT FROM THE UA LOW ACROSS
NWRN OLD MEXICO...RADAR ANALYSIS DEPICTED SCATTERED SHOWERS
DEVELOPING ACROSS THE LOW ROLLING PLAINS AND BIG COUNTRY AREAS. WITH
THE LLJ PROGGED TO INCREASE TO 30-40 KTS ACROSS THE ROLLING PLAINS
WITHIN THE NEXT FEW HOURS COUPLED WITH INCREASING LARGE SCALE ASCENT
AND A MOISTENING ATMOSPHERE /PWATS INCREASING TO AOA 1.10
INCHES/...CHANCES FOR ADDITIONAL SHOWERS AND THUNDERSTORMS WILL BE
ON THE INCREASE PARTICULARLY ACROSS THE ROLLING PLAINS. SOME OF THIS
ACTIVITY COULD POSE A THREAT FOR MODERATE TO HEAVY RAINFALL AS
PWATS INCREASE TO ABOVE 1.00 INCH THROUGHOUT THIS MORNING.
FURTHERMORE...MID-LEVEL CAPE VALUES OF 1000-1500 J/KG COMBINED WITH
0-6 KM BULK SHEAR VALUES AOA 40 KTS...SUGGEST SOME OF THE ACTIVITY
COULD APPROACH STRONG LEVELS WITH HAIL BEING THE PRIMARY THREAT
/PARTICULARLY ACROSS THE LOW ROLLING PLAINS/. STORMS WILL LINGER INTO
EARLY AFTN WHERE THEREAFTER...MODEL SOUNDINGS EXHIBITING A DRYING
PROFILE AND THE UA LOW MOVING EAST TOWARDS SE TX WILL RESULT IN
PRECIP EXITING THE REGION. BY LATE THIS EVENING/EARLY TONIGHT...A
DEEPENING SFC LOW PROGRESSING EAST ACROSS THE CENTRAL PLAINS WILL
PROMOTE W-SW SFC WINDS TO BECOME SLIGHTLY BREEZY BY THE END OF THE
SHORT TERM PERIOD.
TEMPS WILL BE A FEW DEGREES ABOVE NORM TODAY /MIDDLE TO UPPER 60S/
FOLLOWED BY A RELATIVELY MILD NIGHT /UPPER 30S TO MIDDLE 40S/.
LONG TERM...
NO SIGNIFICANT CHANGES TO THE FCST THIS MORNING. MODELS REMAIN
CONSISTENT IN KEEPING THE SRN HIGH PLAINS UNDERNEATH NORTHWESTERLY
FLOW ALOFT. A COUPLE OF SHORT WAVE TROUGHS MOVING THROUGH THIS
UPPER FLOW WILL PRODUCE A COUPLE PERIODS OF BREEZY TO WINDY
CONDITIONS SUNDAY AND MONDAY...THE STRONGEST WINDS COMING SUNDAY
ACROSS THE SWRN HALF OF THE FCST AREA...POSSIBLY MEETING ADVISORY
CRITERIA FOR A PERIOD OF TIME DURING THE AFTERNOON HOURS. TEMPS
NEAR OR JUST BELOW SEASONAL NORMS WITH THE WARMEST DAYS LIKELY
BEING WEDNESDAY AND THURSDAY. STILL SOME MODEL SOLUTIONS SHOWING
A BRIEF INCURSION OF COLD AIR TOWARD FRIDAY...BUT CERTAINLY NOW
CONSENSUS IN THAT REGARD ATTM.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 67 38 53 23 49 / 10 0 10 10 0
TULIA 67 40 53 25 52 / 20 10 10 10 0
PLAINVIEW 67 41 56 26 53 / 20 10 10 10 0
LEVELLAND 66 42 60 27 53 / 20 0 0 10 0
LUBBOCK 66 43 61 27 54 / 50 10 0 10 0
DENVER CITY 65 41 62 28 53 / 30 0 0 10 0
BROWNFIELD 65 42 61 28 54 / 50 10 0 10 0
CHILDRESS 67 45 62 32 56 / 60 10 0 10 0
SPUR 67 45 63 35 58 / 60 10 0 10 0
ASPERMONT 69 46 66 34 58 / 80 10 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
01
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
658 AM CST SAT NOV 22 2014
.UPDATE...
THE KDRT UPPER AIR SOUNDING JUST CAME IN AND IS SHOWING
SUBSTANTIAL MID-LEVEL LAPSE RATES ABOVE A LIFTING CAP. THIS CAP
SHOULD COMPLETELY ERODE SHORTLY AS LIFT CONTINUES TO OVERSPREAD
THE AREA. THE 700-500MB LAPSE RATES ON THE SOUNDING ARE PUSHING 9
C/KM. THE 500 TEMPERATURE COOLED FROM -12C TO -17C IN JUST 12
HOURS. WE ARE GETTING MORE CONCERNED WITH THE SEVERE HAIL
POTENTIAL FROM ANY STORMS WHICH ARE ABLE TO BECOME ROOTED AND
SUSTAINED. ANOTHER CONCERNING CHANGE IS REDEVELOPMENT SHOWING UP
ON THE HRRR. THE HRRR IS OUT NOW TO 1Z AND IS SHOWING
REDEVELOPMENT OF WHAT IS MOST LIKELY TO BE STRONG TO SEVERE
THUNDERSTORMS ALONG THE I-35 CORRIDOR BY 23-00Z. THIS WAS SHOWN
THE PAST SEVERAL DAYS FROM THE NAM...BUT NOW THAT THERE IS SUPPORT
FROM THE HRRR THERE MAY BE SOMETHING TO IT. UPDATED THE GRIDS TO
INCREASE POPS AFTER 00Z FOR AREAS NEAR THE I-35 CORRIDOR. ANOTHER
ASPECT TO THIS IS IF WE GET ANOTHER ROUND OF STORMS...FORECASTED
RAIN TOTALS WILL INCREASE AS WELL. UPDATED THE HWO TO MENTION
ISOLATED 5 INCH TOTALS AND LOCALIZED FLASH FLOODING.
HAMPSHIRE
&&
.PREV DISCUSSION... /ISSUED 529 AM CST SAT NOV 22 2014/
AVIATION DISCUSSION...FOR 12Z TAF PACKAGE...
SCATTERED TO POTENTIALLY WIDESPREAD THUNDERSTORMS WILL BE POSSIBLE
FOR MAINLY THE I35 CORRIDOR TERMINALS THROUGHOUT MUCH OF THE TAF
PERIOD. SHORT TERM MODELS SUGGEST THAT STORM DEVELOPMENT WILL
OCCUR LATE MORNING IN THE VICINITY OF ALL TERMINALS BUT THE
MAJORITY OF THE DEVELOPMENT SHOULD BE ABOUT 50 MILES WEST OF THE
I35 CORRIDOR AND EAST.
BEGINNING 18Z AND LASTING THROUGH 03Z...POTENTIALLY SEVERE
THUNDERSTORMS WILL IMPACT TERMINALS OFF AND ON. INCLUDED +TSRA
WITH IFR VIS TO ENCOMPASS THE MAIN IMPACTS TO THE TERMINALS. CIGS
SHOULD REMAIN AT MVFR LEVELS DURING THE DAY BUT MAY DIP TO IFR
DURING THE MORE SIGNIFICANT STORMS. EXPECT THESE IMPACTS TO EXIT
QUICKLY FROM THE AREA AFTER 03Z. THEN VFR SHOULD PREVAIL DURING
THE REMAINDER OF THE PERIOD.
NOTE FOR KDRT...MODELS SUGGEST A SECOND ROUND OF TSRA TO DEVELOP
IN THE VICINITY NEAR 00Z. THIS IS A RECENT BUT CONSISTENT
DEVELOPMENT IN THE MODELS SO INCLUDED PROB30 MENTION TO ACCOUNT
FOR THIS.
PREV DISCUSSION... /ISSUED 342 AM CST SAT NOV 22 2014/
SHORT TERM (TODAY THROUGH SUNDAY)...
LIGHT SHOWER ACTIVITY REMAINS SCATTERED AROUND THE AREA IN
RESPONSE TO CONTINUED WEAK LIFT ASSOCIATED WITH THE LOW-LEVEL JET.
THE JET IS STRONGEST ACROSS THE CENTRAL AND WESTERN ZONES AND THIS
IS WHERE THE HIGHEST CONCENTRATION OF ACTIVITY IS LOCATED. THE
POTENT UPPER LEVEL LOW IS CURRENTLY LOCATED OVER NORTHERN MEXICO
AND IT CONTINUES TO MOVE EAST. THE LARGE SCALE FORCING FOR ASCENT
CAN EASILY BE SEEN ON IR/WV SATELLITE IMAGERY AT THE PRESENT TIME.
THE FORCING IS SHOWN BY THE INCREASING MID-HIGH LEVEL CLOUDS THAT
ARE OVERSPREADING WEST TEXAS. THE MAIN UPPER FORCING SHOULD ARRIVE
TO SOUTH CENTRAL TEXAS LATER THIS MORNING AND CONTINUE THROUGH THE
AFTERNOON AND EVENING HOURS. UNTIL THE MAIN UPPER FOCUS FOR LIFT
ARRIVES...WE SHOULD ONLY CONTINUE TO SEE THIS ISOLATED TO
SCATTERED SHOWER ACTIVITY WITH PERHAPS AN ISOLATED THUNDERSTORM.
THUNDERSTORMS WILL MOST LIKELY BEGIN TO INCREASE IN COVERAGE IN
THE MID TO LATE MORNING HOURS AS THE UPPER LIFT ARRIVES. INITIALLY
THERE WILL BE ABOUT 1500 J/KG OF CAPE ACROSS THE WESTERN HALF OF
THE CWA WITH 30-35 KNOTS OF 0-6 KM SHEAR. CAPE VALUES WILL DROP
OFF TO 1000 J/KG OR LESS ACROSS THE EASTERN ZONES. THE INITIAL
DEVELOPMENT OF STORMS COULD LEAD TO WEAK SUPERCELLS IN THE WESTERN
HALF OF THE CWA IN THE AREA OF BEST INSTABILITY. HOWEVER...ONCE
ACTIVITY BECOMES MORE WIDESPREAD THIS AFTERNOON...THERE MAY END UP
BEING TOO MUCH ACTIVITY TO REALIZE THE PEAK CAPE VALUES. HIGH-RES
GUIDANCE IS CONSISTENTLY SHOWING A LARGE AREA OF PRECIP OVER THE
CWA THAT MOVES FROM WEST TO EAST AND OUT OF THE CWA BY 03Z. THE
SHERB PARAMETER WHICH IS DECENT IN PICKING UP SEVERE POTENTIAL FOR
THESE LOW CAPE/HIGH SHEAR ENVIRONMENTS /EASTERN ZONES/ IS LESS
THAN WHAT WAS FORECASTED YESTERDAY...BUT IS STILL NEAR THE
THRESHOLD TO SUPPORT THE NOTION FOR SOME POSSIBLE SEVERE WIND
GUSTS OUT OF ANY LINE SEGMENTS WHICH FORM WITHIN THE LARGE MASS OF
THUNDERSTORMS. CURRENT THINKING IS THAT INITIALLY...SOME
THUNDERSTORMS COULD PRODUCE MARGINALLY SEVERE HAIL MAINLY ACROSS
THE WESTERN HALF OF THE AREA DURING THE LATE MORNING AND INTO THE
EARLY AFTERNOON. THEN...SOME MARGINALLY SEVERE WIND GUSTS WOULD
BE THE MAIN MODE OF SEVERE CONVECTION FROM ANY POSSIBLE LINE
SEGMENTS IN THE EASTERN ZONES. THE RISK FOR TORNADOES IS NON-
ZERO...BUT LOW WITH THE BEST POTENTIAL BEING IN THE SOUTHEAST
ZONES...WHERE THE BEST LOW-LEVEL SHEAR IS LOCATED.
PW VALUES WILL RISE UP TO 1.5 INCHES ACROSS THE EASTERN AND
NORTHERN ZONES. THIS IS ABOUT 2 STANDARD DEVIATIONS ABOVE NORMAL
FOR THIS TIME OF THE YEAR. THEREFORE...WE COULD SEE LOCALLY HEAVY
RAINFALL...MAINLY ACROSS THESE MENTIONED AREAS. WPC DAY 1 QPF
VALUES RANGE FROM NEAR 1/4 OF AN INCH NEAR THE RIO GRANDE TO NEAR
2 INCHES IN OUR NORTHERN ZONES. THIS SEEMS REASONABLE...BUT SOME
ISOLATED LOCATIONS COULD RECEIVE UP TO 4 INCHES OF RAIN.
ALL ACTIVITY IS EXPECTED TO BE EAST OF THE AREA BY 3Z OR 9 PM.
WEST WINDS AT THE SURFACE WILL CONTINUE ON SUNDAY GIVING US A
DOWNSLOPE COMPONENT FROM WEST TO EAST. THIS USUALLY LEADS TO WARM
TEMPERATURES AND HIGHS SUNDAY WILL REACH THE MID 70S TO NEAR 80
DEGREES.
LONG TERM (SUNDAY NIGHT THROUGH FRIDAY)...
THE WEATHER IN THE EXTENDED IS EXPECTED TO BE FAIRLY QUIET. A WEAK
FRONT WILL MOVE THROUGH THE AREA OVERNIGHT SUNDAY. THIS FRONT IS IN
RESPONSE TO AN UPPER LEVEL TROUGH MOVING THROUGH THE PLAINS. THIS
FRONT WILL BE DRY AS MOISTURE WILL REMAIN SHUNTED OFF TO THE EAST.
THE REST OF THE WEEK WILL REMAIN DRY AND THE NEXT FRONT SHOULD
MOVE INTO THE AREA AROUND FRIDAY. THE WEATHER FOR THANKSGIVING
SHOULD BE PRETTY SEASONAL WITH HIGHS IN THE 60S AND LOWS IN THE
30S/40S.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 69 56 80 46 64 / 100 60 0 - -
AUSTIN BERGSTROM INTL AIRPORT 71 56 80 46 64 / 100 70 0 - -
NEW BRAUNFELS MUNI AIRPORT 75 56 81 46 65 / 90 60 0 - -
BURNET MUNI AIRPORT 67 53 77 42 62 / 100 50 0 - -
DEL RIO INTL AIRPORT 73 51 80 46 65 / 40 20 0 - -
GEORGETOWN MUNI AIRPORT 68 55 78 44 62 / 100 60 0 - -
HONDO MUNI AIRPORT 73 53 78 45 64 / 70 50 0 - -
SAN MARCOS MUNI AIRPORT 70 56 80 45 64 / 90 70 0 - -
LA GRANGE - FAYETTE REGIONAL 73 57 79 46 64 / 90 90 0 - -
SAN ANTONIO INTL AIRPORT 75 55 80 46 65 / 80 60 0 - -
STINSON MUNI AIRPORT 76 56 81 47 66 / 80 60 0 - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...03
SYNOPTIC/GRIDS...29
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
524 AM CST SAT NOV 22 2014
.AVIATION...
VLIFR FOG AND LIFR CLOUD DECKS HAVE DEVELOPED AT KCDS THIS
MORNING...WITH KLBB VIS DROPPING BELOW 10 SM AND FEW DECKS BELOW
2000 FT AGL. WILL EXPECT KLBB TO FURTHER DETERIORATE LATER THIS
MORNING TO MVFR FOG AND IFR DECKS. CONDITIONS WILL IMPROVE TO VFR
CATEGORY BY MID-MORNING. LIGHT AND VARIABLE WINDS WILL VEER TO THE
WEST SOUTHWEST THIS AFTN AND BECOME SLIGHTLY BREEZY TOWARDS THE
END OF TAF PERIOD.
&&
.PREV DISCUSSION... /ISSUED 214 AM CST SAT NOV 22 2014/
SHORT TERM...
MAIN FOCUS FOR THE SHORT TERM PERIOD CONTINUES TO BE THE UA LOW
DIGGING ESE ACROSS NWRN OLD MEXICO EARLY THIS MORNING...WHICH WILL
AID TO INCREASE PRECIP CHANCES LATER THIS MORNING.
AN AREA OF STRATUS AND FOGGY CONDITIONS ONCE AGAIN DEVELOPED ACROSS
ERN TEXAS AND OKLAHOMA PER 08Z METARS...THUS COINCIDING WITH THE
BEST SFC MOISTURE /DEWPOINTS IN THE 50S AND 60S/. LOW CLOUDS AND FOG
HAVE IMPACTED THE FAR SERN TX PANHANDLE...WHICH IS NOT SURPRISING
GIVEN A LOW TEMP-DEWPOINT SPREAD. THE HRRR SOLUTION HANDLED THE
EVOLUTION OF THE LOW CLOUDS AND FOG QUITE WELL YESTERDAY...AND SINCE
IT SHOWS A CONTINUAL WESTWARD DEVELOPMENT FOR THE NEXT SEVERAL HOURS
UNTIL MID-MORNING WHERE THEREAFTER CONDITIONS WILL IMPROVE...THIS
FORECAST PACKAGE WILL REFLECT THAT PROGRESSION.
AS PREVIOUSLY STATED...THE BEST MOISTURE AXIS WAS NOTED EAST OF THE
FA AND WITH THE AID OF A BIT OF UL SUPPORT FROM THE UA LOW ACROSS
NWRN OLD MEXICO...RADAR ANALYSIS DEPICTED SCATTERED SHOWERS
DEVELOPING ACROSS THE LOW ROLLING PLAINS AND BIG COUNTRY AREAS. WITH
THE LLJ PROGGED TO INCREASE TO 30-40 KTS ACROSS THE ROLLING PLAINS
WITHIN THE NEXT FEW HOURS COUPLED WITH INCREASING LARGE SCALE ASCENT
AND A MOISTENING ATMOSPHERE /PWATS INCREASING TO AOA 1.10
INCHES/...CHANCES FOR ADDITIONAL SHOWERS AND THUNDERSTORMS WILL BE
ON THE INCREASE PARTICULARLY ACROSS THE ROLLING PLAINS. SOME OF THIS
ACTIVITY COULD POSE A THREAT FOR MODERATE TO HEAVY RAINFALL AS
PWATS INCREASE TO ABOVE 1.00 INCH THROUGHOUT THIS MORNING.
FURTHERMORE...MID-LEVEL CAPE VALUES OF 1000-1500 J/KG COMBINED WITH
0-6 KM BULK SHEAR VALUES AOA 40 KTS...SUGGEST SOME OF THE ACTIVITY
COULD APPROACH STRONG LEVELS WITH HAIL BEING THE PRIMARY THREAT
/PARTICULARLY ACROSS THE LOW ROLLING PLAINS/. STORMS WILL LINGER INTO
EARLY AFTN WHERE THEREAFTER...MODEL SOUNDINGS EXHIBITING A DRYING
PROFILE AND THE UA LOW MOVING EAST TOWARDS SE TX WILL RESULT IN
PRECIP EXITING THE REGION. BY LATE THIS EVENING/EARLY TONIGHT...A
DEEPENING SFC LOW PROGRESSING EAST ACROSS THE CENTRAL PLAINS WILL
PROMOTE W-SW SFC WINDS TO BECOME SLIGHTLY BREEZY BY THE END OF THE
SHORT TERM PERIOD.
TEMPS WILL BE A FEW DEGREES ABOVE NORM TODAY /MIDDLE TO UPPER 60S/
FOLLOWED BY A RELATIVELY MILD NIGHT /UPPER 30S TO MIDDLE 40S/.
LONG TERM...
NO SIGNFICANT CHANGES TO THE FCST THIS MORNING. MODELS REMAIN
CONSISTENT IN KEEPING THE SRN HIGH PLAINS UNDERNEATH NORTHWESTERLY
FLOW ALOFT. A COUPLE OF SHORT WAVE TROUGHS MOVING THROUGH THIS
UPPER FLOW WILL PRODUCE A COUPLE PERIODS OF BREEZY TO WINDY
CONDITIONS SUNDAY AND MONDAY...THE STRONGEST WINDS COMING SUNDAY
ACROSS THE SWRN HALF OF THE FCST AREA...POSSIBLY MEETING ADVISORY
CRITERIA FOR A PERIOD OF TIME DURING THE AFTERNOON HOURS. TEMPS
NEAR OR JUST BELOW SEASONAL NORMS WITH THE WARMEST DAYS LIKELY
BEING WEDNESDAY AND THURSDAY. STILL SOME MODEL SOLUTIONS SHOWING
A BRIEF INCURSION OF COLD AIR TOWARD FRIDAY...BUT CERTAINLY NOW
CONSENSUS IN THAT REGARD ATTM.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 67 38 53 23 49 / 10 0 10 10 0
TULIA 67 40 53 25 52 / 10 10 10 10 0
PLAINVIEW 67 41 56 26 53 / 20 10 10 10 0
LEVELLAND 66 42 60 27 53 / 20 0 0 10 0
LUBBOCK 66 43 61 27 54 / 20 10 0 10 0
DENVER CITY 65 41 62 28 53 / 20 0 0 10 0
BROWNFIELD 65 42 61 28 54 / 20 10 0 10 0
CHILDRESS 67 45 62 32 56 / 30 10 0 10 0
SPUR 67 45 63 35 58 / 50 10 0 10 0
ASPERMONT 69 46 66 34 58 / 80 10 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
29
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
258 PM CST SAT NOV 22 2014
.SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT
WARM FNT WAS SITUATED WELL TO THE N OF AR THIS AFTN...WITH S/SELY
WINDS NOTED ACRS THE FA. WIDESPREAD SHRA/ISOLD TSRA HAS CONTD TO
AFFECT MUCH OF W-CNTRL AND NRN AR AS ANOTHER UPR LVL IMPULSE LIFTS
THRU THE REGION. PARTLY CLOUDY SKIES WERE NOTED OVR THE SERN HALF OF
THE AREA....WITH MID AFTN TEMPS IN THE 60S TO ARND 70.
THE PRIMARY WX MAKER OVR THE NEXT 24 TO 36 HRS WL BE THE MAIN UPR
LVL STORM SYS THAT WL CONT TO TRACK EWD INTO CNTRL TX TNGT AND
EVENTUALLY LIFT NEWD THRU AR ON SUN. SHRA/EMBEDDED TSRA WL BCM MORE
WIDESPREAD FM THE SW OVERNIGHT AND CONT ON SUN.
ONE FCST ISSUE CONTS TO BE THE ONSET/PROGRESS WITH THE MAIN WAVE OF
RAINFALL LATER TNGT AND SUN. THE HRRR MODEL HAS STAYED CONSISTENT
TODAY INDCG THE BULK OF THE RAIN WL NOT AFFECT THE FA FM THE SW
UNTIL AFT MIDNIGHT TNGT AND HAVE TRENDED POPS TOWARD THIS SOLUTION.
EXPECT WIDESPREAD SHRA/ISOLD TSRA SUN MRNG...SLOLY DCRSG FM THE SW
SUN AFTN AND EVENING AS THE STORM SYS LIFTS OUT OF THE AREA. LEFT
SOME SMALL RAIN CHCS IN FOR NRN AR SUN NGT AS THE MAIN UPR LVL TROF
SWINGS THRU THE AREA.
BREEZY WLY WINDS WL BRING COOLER AND MUCH DRIER AIR BACK TO THE MID
SOUTH FOR THE REST OF THE PD. SECONDARY CDFNT WL PASS THRU THE AREA
ON TUE...WITH A REINFORCING SHOT OF COOLER AIR.
&&
.LONG TERM...WEDNESDAY THROUGH SATURDAY
NEXT WEAK COLD FRONT IS DUE ON WEDNESDAY. AT THIS POINT...MOISTURE
LOOKS TOO LIMITED TO INCLUDE ANY POPS. ANOTHER WEAK FRONT IN THE
THURSDAY/FRIDAY TIME FRAME. WITH THESE REINFORCING SHOTS OF COOL
AIR...TEMPERATURES WILL REMAIN QUITE A BIT BELOW NORMAL THROUGH THE
END OF THE WEEK. JUST BEYOND THIS FORECAST PERIOD...THERE SHOULD BE
MORE CLOUDS AND PROBABLY SOME LOW POPS FOR AT LEAST A COUPLE OF DAYS.
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...44 / LONG TERM...28
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
302 PM CST SAT NOV 22 2014
.SHORT TERM...THIS AFTERNOON AND TONIGHT...
258 PM CST
FOR THE REMAINDER OF THIS AFTERNOON AND THROUGH TONIGHT...AN
INFLUX OF WARM...MOIST AIR WILL CONTINUE TO STREAM INTO THE UPPER
MIDWEST. LATEST SFC ANALYSIS SHOWS DEWPOINTS IN THE 50S OVER
MISSOURI WHILE DEWPOINTS ACROSS NRN IL. NWRN IN HAVE CLIMBED INTO
THE MIDDLE TO UPPER 40S. TEMPERATURES HAVE ALSO BEEN ON THE RISE
THROUGH THE DAY WITH TEMPERATURES AT OR IN EXCESS OF 50F AS FAR
NORTH AS MIDWAY AIRPORT AND AURORA AS OF 230PM CST. TEMPERATURES
ARE EXPECTED TO CONTINUE TO RISE INTO THE EARLY EVENING UNDER THE
PERSISTENT WARM...MOIST ADVECTION UNDER A STRONG SWLY LOW LEVEL
JET WITH 850MB WINDS UP TO 45KT...TEMPERATURES WILL LIKELY HOVER
AROUND THE 50 DEGREE MARK THROUGH THE NIGHT. ADDITIONAL LIGHT RAIN
OR DRIZZLE WILL PERSIST THROUGH THE EVENING AND OVERNIGHT...WITH
AREAS OF FOG POSSIBLE.
KREIN
&&
.LONG TERM...SUNDAY THROUGH FRIDAY...
258 PM CST
MORE SIGNIFICANT RAINFALL IS SETTING UP FOR SUNDAY AND INTO
SUNDAY NIGHT AS A STRONG SRN STREAM SHORTWAVE LIFTING OUT OF THE
SOUTH HIGH PLAINS PHASES WITH ANOTHER SHORTWAVE LIFTING FROM THE
SOUTHWEST GULF COAST REGION. THESE SYSTEM WILL RESULT IN A
DEEPENING SFC LOW OF 984MB NEAR ST LOUIS BY SUNDAY EVENING. THE
MODELS CONTINUE TO ADVERTISE PWAT VALUES AROUND 1.2 INCHES...WHICH
IS AT THE 99TH PERCENTILE FOR PWATS FOR THE REGION. THIS PHASING
OF THE TWO SRN STREAM SYSTEMS COMBINED WITH THE UNUSUALLY HIGH
PWAT AIRMASS WILL COMBINE TO FOCUS STEADY RAINFALL ACROSS THE
REGION THROUGH THE DAY ON SUNDAY AND INTO SUNDAY EVENING...WITH A
CORRIDOR OF THE HEAVIEST RAIN OVER THE NWRN PORTIONS OF THE
CWA...GENERALLY NORTH OF A LINE FROM PERU TO MCHENRY...WHERE
UPWARDS OF A HALF INCH PER 3 HOUR PERIOD IS POSSIBLE. LATER SUNDAY
NIGHT...THE PHASED SRN STREAM SYSTEM WILL BEGIN TO PHASE WITH A
NRN STREAM SHORTWAVE...WITH LOW PRESSURE RAPIDLY DEEPENING AS IT
LIFTS THROUGH THE UPPER GREAT LAKES. WHILE THE GUIDANCE IS
RELATIVELY CONSISTENT ON THE TRACK AND TIMING OF THE DEEPENING
LOW...THE GFS IS A MUCH STRONGER OUTLIER IN THE GUIDANCE
ENVELOPE...DEEPENING THE CENTRAL PRESSURE TO ARND 966MB BY MIDDAY
MONDAY...WHILE MUCH OF THE OTHER GUIDANCE ONLY DEEPENS THE LOW TO
ARND 980MB. WHILE THE GFS SOLUTION MAY BE TOO DEEP...LIKELY
DRAWING COLDER AIR INTO THE SYSTEM FASTER THAN THE OTHER
MODELS...OR TAPPING MORE NRN STREAM ENERGY...THERE WILL STILL
LIKELY BE A DEEP LOW DEVELOPING OVER THE UPPER GREAT LAKES SUNDAY
NIGHT INTO MONDAY...WHOSE CIRCULATION PATTERN WILL COVER A LARGE
EXPANSE FROM THE EAST-CENTRAL PLAINS TO NERN QUEBEC. A STRONG WLY-
NWLY GRADIENT WILL SET UP ON THE SWRN PERIPHERY OF THE
SYSTEM...LEADING TO STRONG...GUSTY WINDS ACROSS THE CWA FROM EARLY
MONDAY MORNING THROUGH LATE MONDAY EVENING. THE STRONGEST WINDS
SHOULD OCCUR FROM LATE MORNING THROUGH LATE EVENING...WITH
SUSTAINED WINDS OF 25-30 MPH AND PEAK GUSTS OF 35-40 MPH.
HOWEVER...IF THE SYSTEM EVOLVES A LITTLE DEEPER THAT THE CONSENSUS
GUIDANCE AND DEEPENS CLOSER TO THE OUTLIER GFS SOLUTION...WINDS
ACROSS THE AREA COULD REACH WIND ADVISORY LEVELS OF SUSTAINED
WINDS OF 30 MPH OR HIGHER OR GUSTS OF 45 MPH OR GREATER.
ALSO...AS THE SFC LOW BEGINS TO LIFT OUT TO THE NORTHEAST MONDAY
AFTERNOON...MUCH COOLER AIR WILL BEGIN TO FILTER ACROSS THE REGION.
AS THE PATTERN TRANSITIONS FROM ONE OF STRONG WARM ADVECTION SUNDAY
NIGHT TO STRONG COLD ADVECTION BY MONDAY MORNING...FOLLOWING THE
PASSAGE OF A STRONG ASSOCIATED COLD FRONT...LINGERING PCPN WILL
BEGIN TO TRANSITION FROM RAIN TO SNOW. SINCE THE COLD AIR SHOULD
EXTEND THROUGH THE ENTIRE ATMOSPHERE...THERE SHOULD BE A MORE
STRAIGHTFORWARD TRANSITION FROM RAIN TO SNOW WITH LITTLE CHANCE FOR
ANY FREEZING RAIN OR SLEET. THERE COLD BE SOME ISSUES WITH WATER
FLASH FREEZING ON ELEVATED SURFACES AS SUB-FREEZING AIR QUICKLY
FILTERS ACROSS THE REGION BY LATE MONDAY AFTERNOON.
THE STRONG COLD ADVECTION WILL PERSIST THROUGH THE NIGHT WITH
TEMPERATURES DROPPING TO THE LOWER TO MIDDLE 20S BY DAYBREAK TUESDAY
MORNING. THE PERSISTENT COLD ADVECTION WILL ALLOW FOR LITTLE
DIURNAL WARMING WITH HIGHS ON TUESDAY EXPECTED TO BE IN THE UPPER
20S TO ARND 30F OVER THE FAR SERN PORTIONS OF THE CWA. THERE BE SOME
MODERATION TO TEMPERATURES ON WEDNESDAY AS WEAK SFC RIDGING CROSSES
THE AREA ALLOWING TEMPERATURES TO RISE INTO THE MIDDLE 30S.
WEDNESDAY SHOULD BE THE WARMEST OF THE EXTENDED PERIOD. A SERIES OF
STRONG NORTHERN STREAM SHORTWAVES IS EXPECTED TO CARVE OUT A BROAD
LONGWAVE TROUGH OVER ERN CONUS FROM THE MISSISSIPPI VALLEY TO THE
EAST COAST. THE UPPER LEVEL PATTERN SHOULD DECREASE IN AMPLITUDE
THROUGH THE EXTENDED PERIOD...BUT THE LOCAL AREA IS EXPECTED TO
REMAIN UNDER GENERAL NWLY FLOW ALOFT...KEEPING A PERSISTENT FETCH OF
COLD AIR ACROSS THE AREA. BY LATE NEXT WEEK...HIGH TEMPERATURES WILL
STRUGGLE INTO THE LOWER TO MIDDLE 20S...WHILE OVERNIGHT LOWS DROP
INTO THE LOWER TO MIDDLE TEENS...WITH THE POSSIBILITY OF THE NWRN
PORTIONS OF THE CWA...INCLUDING THE ROCKFORD AREA DROPPING INTO THE
SINGLE DIGITS FRIDAY AND SATURDAY MORNING. THE SERIES OF SHORTWAVES
RIPPLING THROUGH THE NORTHWEST FLOW SHOULD BRING PERIODIC CHANCES
FOR SOME LIGHT SNOW...BUT CONFIDENCE IS LOW ON THE EXACT TIMING.
CONFIDENCE IS A LITTLE HIGHER THAT ANY SNOW THAT DOES OCCUR SHOULD
BE LIGHT AS THERE WILL BE LITTLE ENVIRONMENTAL MOISTURE OR SFC
FORCING. ANY SNOW GENERATION WILL HAVE TO RELY ON MID-LEVEL FORCING
AND MEAGER MOISTURE CONTENT.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* PATCHY IFR CIGS...TO LOW END MVFR CIGS THIS AFTN. LIKELY
TRENDING BACK TOWARDS IFR OVERNIGHT THRU SUN MORNING.
* VSBY WILL HOVER BETWEEN 3-6SM THIS AFTN...POSSIBLY FALLING TO
JUST UNDER 3SM OVERNIGHT THRU SUN MORNING.
* LOW-LEVEL WIND SHEAR DEVELOPING TONIGHT. ARND 2KFT AGL FROM THE
SOUTHWEST NEARING 45KT.
* RAIN SHOWERS DEVELOPING EARLY SUN MORNING...INCREASING IN
COVERAGE CLOSER TO MIDDAY.
BEACHLER
//DISCUSSION...UPDATED 18Z...
VERY MOIST AIR MASS CONTINUES TO FEED NORTHEAST ACROSS NORTHERN
IL/NORTHWEST IN AIRFIELDS THIS AFTERNOON. LITTLE IMPROVEMENT TO
THE CIGS IS EXPECTED...AS A RESULT HAVE HELD CIGS DOWN ARND LOW
END MVFR THIS AFTN AND WILL LIKELY TREND BACK TOWARDS IFR CONDS
OVERNIGHT. GENERALLY EXPECT CIGS ARND 500-900FT AGL THRU THE
OVERNIGHT HOURS. WIND DIR WILL NOT CHANGE MUCH THIS
AFTN/EVE/OVERNIGHT...MAINLY FROM THE SOUTH WITH SPEEDS ALSO NOT
CHANGING MUCH ARND 10-12KT. GIVEN HOW MOIST THE ATMOSPHERE
IS...PERIODIC ROUNDS OF DRIZZLE CAN BE EXPECTED THRU THIS
AFTN/EARLY EVE WILL A LULL LATE THIS EVE. WIND SHEAR IS ALSO
POISED TO DEVELOP THIS EVENING...WITH WINDS ARND 2KFT AGL FROM THE
SOUTHWEST INCREASING TO 40-45KT.
GUIDANCE HAS CONTINUED TO SUGGEST DEVELOPING RAIN SHOWERS AFT
MIDNIGHT/EARLY SUN...SO HAVE HELD ONTO THE MENTION OF LGT RAIN
EARLY SUN. THEN IT APPEARS THE BETER COVERAGE FOR PERHAPS MORE
STEADY RAIN WILL OCCUR LATE SUN MORNING...AND COULD PERSIST THRU
SUN AFTN.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN CIGS HOLDING AT LOW END MVFR...AND MEDIUM
CONFIDENCE ON TIMING CIGS TRENDING BACK TOWARDS IFR.
* HIGH CONFIDENCE IN WIND DIR/SPEED.
* MEDIUM CONFIDENCE IN LOW-LEVEL WIND SHEAR.
* HIGH CONFIDENCE IN DRIZZLE THRU THIS AFTN...THEN MEDIUM
CONFIDENCE IN TIMING OF ENDING THE MENTION OF DRIZZLE.
* HIGH CONFIDENCE IN LIGHT RAIN DEVELOPING EARLY SUN WITH BETTER
COVERAGE LATE SUN MORNING/AFTN. MEDIUM CONFIDENCE IN PRECISE
TIMING OF RAIN IMPACTING TAF SITES.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...RAIN AND IFR PROBABLE. SOUTHERLY WINDS.
MONDAY...CHANCE OF RAIN AND SNOW. STRONG WEST TO SOUTHWEST WINDS.
TUESDAY...MVFR CIGS POSSIBLE. WESTERLY WINDS.
WEDNESDAY...CHANCE OF SNOW AND MVFR. SOUTHWEST WINDS.
THURSDAY...FLURRIES AND MVFR POSSIBLE. NORTHWEST WINDS.
FRIDAY...VFR PROBABLE. SOUTHWEST WINDS.
MTF
&&
.MARINE...
231 PM...STRONG LOW PRESSURE WILL MOVE ALONG THE U.S. CANADIAN
BORDER TONIGHT AND BEGIN TO WEAKEN AS IT REACHES WESTERN LAKE
SUPERIOR SUNDAY AFTERNOON. ANOTHER LOW WILL DEVELOP OVER THE
SOUTHERN PLAINS TONIGHT AND MOVE NORTH TO SOUTHERN LAKE MICHIGAN
AS IT DEEPENS AND ABSORBS THE LOW OVER WESTERN LAKE SUPERIOR. THIS
LOW WILL THEN DEEPEN FURTHER AS IT REACHES EASTERN LAKE SUPERIOR
MONDAY MORNING. THERE STILL REMAINS SOME DIFFERENCES AMONG THE
MODELS REGARDING HOW STRONG THIS LOW WILL BECOME. THE DEEPEST OF
THE MODELS HAS A PRESSURE OF 28.5 INCHES MIDDAY MONDAY. CONFIDENCE
IS INCREASING FOR MID/HIGH END GALES SO WILL BE GOING WITH A GALE
WATCH FOR MONDAY AND MONDAY NIGHT. STORM FORCE GUSTS OR PREVAILING
WINDS ALSO REMAIN POSSIBLE. WINDS STEADILY DIMINISH TUESDAY AS
HIGH PRESSURE MOVES ACROSS THE SOUTHERN LAKES AND OHIO VALLEY.
ANOTHER LOW IS EXPECTED TO MOVE ACROSS THE LAKES REGION WEDNESDAY
INTO THURSDAY...BRINGING NORTHWEST WINDS TO 30KT ON THURSDAY. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 3 PM SATURDAY.
GALE WATCH...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-
LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878...6 AM MONDAY TO 3 AM TUESDAY.
GALE WATCH...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ868...NOON MONDAY TO 3 AM TUESDAY.
&&
$$
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[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
252 PM CST Sat Nov 22 2014
.SHORT TERM...(Tonight)
ISSUED AT 252 PM CST SAT NOV 22 2014
Weakening 1031 mb high pressure drifting off eastern NC shore while
strong and deepening 985 mb low moving east into sw Sasketchewan.
This was giving a tight pressure gradient over central and southeast IL
this afternoon with very breezy ssw winds 12 to 22 mph and gusts of
25 to 30 mph. SSW winds advecting in much milder and more moist air
from western Gulf of Mexico with temperatures in the mid 50s to lower 60s
(warmest sw areas with Mount Carmel airport at 64F) and dewpoints in
the middle to upper 40s. Cloudy skies across much of central IL with
some breaks in clouds se of I-70 in southeast IL. Isolated light
rain showers over eastern IL this afternoon while showers more
numerous over sw IL from I-64 south into southern MO along and se of
I-44 where a few thunderstorm were a few hours ago. Mid level
moisture spreads northward tonight across areas se of the IL river
and this to increase chances of light rain showers though rainfall
amounts will be light due to weak lift/forcing. Also have patchy
drizzle with lower clouds over IL river valley tonight and areas of
fog overnight (currently getting fog over parts of nw IL and se IA).
Went a few degrees above similar MET/MAV guidance for lows tonight
in the mid to upper 40s due to cloud cover and southerly winds of
10-15 mph and gusts to 20 mph especially this evening.
&&
.LONG TERM...(Sunday through Saturday)
ISSUED AT 252 PM CST SAT NOV 22 2014
The vigorous short wave, lifting out of the southern plains will
phase with a northern stream system tomorrow; The related surface
system will strengthen over the CWA and lift northeast east tomorrow
night through Monday. The associated cold front with this system
will move through the area Monday night and bring the return to
colder air in the region for the beginning of the coming week. This
system is the main challenge with this forecast package this
afternoon. The resulting weather with this system will be for mostly
rain across the whole area tomorrow with the possibility of isolated
thunderstorms in southeastern IL, along and south of I-70, for
tomorrow afternoon through tomorrow evening. The dynamics of this
system do not look very strong, so severe storms are not expected in
southeast Illinois tomorrow afternoon or evening. Areas across the
north will see the areas of fog continuing through tomorrow and
tomorrow night. The fog will dissipate in the north once the low
pressure area moves northeast and the cold front moves through the
area, tomorrow night. The colder air that moves in Sunday night and
Monday, as the system deepens and moves northeast, will bring a
change to the p-type, resulting in rain mixing with snow in the west
Sunday night, and then becoming all snow by Monday. Snowfall
accumulations will be a half inch or less; since the pcpn will be
ending as the system moves northeast.
Temps will remain warm tomorrow but then fall from tomorrow night
through Monday night. Temps on Monday will be steady or slowly
falling in the afternoon, with the 24hr highs likely being around
midnight tomorrow night, and lows late Monday evening.
The remainder of the forecast period, through Saturday, will be
relatively dry. However, the models are bringing in a weak clipper
system Wed through Thur, that will bring a chance of snow to the
northern third of the CWA. Models are fairly consistent with the
location of the track of the low pressure area, but differ on
timing. So will still with a blend of the two models and keep the
chance of snow Wed and Wed night, as with previous forecast; and
then have a chance in the northeast parts for Thur to accommodate
the slower timing of the ECMWF.
Temps will warm some on Wed, ahead of the clipper system, but then
turn cold again after the system moves through and colder air
advects into the region again.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 1155 AM CST SAT NOV 22 2014
MVFR ceilings at PIA and BMI most of this morning (just lifted to
VFR at PIA) while VFR ceilings along I-72 at midday. Meanwhile
isolated to scattered showers had shifted se of the central IL
airports at late morning. HRRR shows MVFR ceilings 2-3k ft
possible at times over central IL this afternoon especially at PIA
and BMI, and this model shifts these lower ceilings along with fog
further north of central IL this evening. Was more pestimistic
with keeping MVFR ceilings and vsbys around tonight and even lower
IFR ceilings at PIA and BMI Sunday morning. Rain showers to become
more likely later this evening/overnight with best chances
shifting into IL river valley by PIA late tonight and Sunday
morning. Breezy ssw winds 12-17 kts with gusts 18-25 kts into this
evening to veer sse Sunday morning and still gust again to 18-23
kts. Kept LLWS in TAFs again tonight until mid morning Sunday
with 2k ft sw winds of 40 kts.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...07
LONG TERM...Auten
AVIATION...07
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
146 PM CST SAT NOV 22 2014
.UPDATE...
917 AM...MORNING UPDATE...TEMPERATURES HAVE WARMED INTO THE UPPER
30S AND LOWER 40S WITH THE THREAT OF FREEZING RAIN OVER AND LET
ADVISORY EXPIRE AT 9 AM.
FOCUS NOW SHIFTS TO THE POTENTIAL FOR DENSE FOG ACROSS THE FAR
NORTHERN AND NORTHWEST PORTIONS OF THE CWA TODAY AND TONIGHT.
VISIBILITIES CURRENTLY BETWEEN 1/2SM AND 2SM. NOT EXPECTING MUCH
IMPROVEMENT IN THESE AREAS TODAY SO ADDED FOG TO THE FORECAST...
GENERALLY NORTH OF I-80 BUT CONFIDENCE REGARDING HOW SOON DENSE
FOG MAY BECOME PREVAILING AND THEN HOW LONG IT WILL LAST IS STILL
LOW. BUT A DENSE FOG ADVISORY FOR PORTIONS OF THE NORTHERN CWA MAY
BE NEEDED LATER TODAY OR THIS EVENING. CMS
&&
.SHORT TERM...
315 AM CST
THROUGH TONIGHT...
THE PRIMARY CONCERNS WITH THE FORECAST CENTER ON FREEZING RAIN
THREAT EARLY THIS MORNING...THEN RAIN POTENTIAL AND AMOUNTS THROUGH
THE REST OF THE WEEKEND.
AN AREA OF SHOWERS IS MOVING QUICKLY NORTHEAST OVER THE IMMEDIATE
REGION AS OF 315 AM. THIS IS WITHIN STRENGTHENING FORCING FROM A
SHORT WAVE TROUGH...AND THIS GREATER LIFT IS COINCIDENT ON THE NOSE
OF A 45 KT LOW-LEVEL JET PER VAD WIND PROFILERS. OVERALL MUCH OF
THIS FORCING AND MODEST SHOWER ACTIVITY WILL CONTINUE TO SHIFT EAST
THROUGH SUNRISE. STEADILY RISING TEMPERATURES HAD LEVELED OFF SOME
VERY EARLY THIS MORNING WITH THE HEAVIER PRECIP INTENSITY...ALTHOUGH
A SLOW INCREASE SHOULD RESTART PRIOR TO DAYBREAK AND PERSIST THROUGH
TODAY AS WARM ADVECTION WINS OUT. TEMPERATURES OF 31 TO 33 AS OF
315 AM MAINLY REMAINED IN THE NORTHERN FORECAST AREA...INCLUDING
ROCKFORD AND THE NORTH CHICAGO METRO...AND PARTS OF NORTHWEST
INDIANA INCLUDING VALPARAISO. PAVEMENT TEMPERATURES FROM A HANDFUL
OF SOURCES VARIED SOME...BUT FOR THE MOST PART WERE ABOVE FREEZING
IN CHICAGO AND SOUTHWARD FROM THERE. SO WILL CONTINUE ADVISORY AS
IS FOR NOW AND MAKE A REASSESSMENT JUST PRIOR TO 6 AM TO SEE IF
ANY PARTS NEED TO CONTINUE TO 9 AM.
WHILE MUCH OF THE MODEST PRECIP SHOULD SHIFT EASTWARD EARLY THIS
MORNING...BROAD ASCENT IN THE MID-LEVELS WILL REMAIN WITH AN UPPER
SPEED MAXIMUM MOVING OVERHEAD. THIS PROBABLY WILL BE ENOUGH FOR
SCATTERED/INTERMITTENT SHOWERS ESPECIALLY THROUGH EARLY AFTERNOON.
IN THE LOWER-LEVELS...HIGH DEW POINT AIR WILL CONTINUE TO BE
ADVECTED NORTHWARD ESTABLISHING THE LOW CLOUDS. ISENTROPIC OMEGA
WITHIN THESE LOWEST LEVELS LOOKS TO SUPPORT AREAS OF DRIZZLE...AND
ALREADY SEEING INDICATIONS OF THIS NEAR THE DVN RDA. SO CONTINUE
AREAS OF DRIZZLE WORDING. TEMPERATURES WILL BE THE WARMEST THEY HAVE
BEEN SINCE LATE ON THE NIGHT OF NOVEMBER 10TH...WITH 40S EXPECTED
AREAWIDE AND EVEN 50 TAGGED SOUTH OF INTERSTATE 80 IN SOME
LOCATIONS. TONIGHT TEMPERATURES SHOULD BASICALLY HOLD STEADY AND
MAYBE EVEN RISE SOME. IF TEMPERATURES ARE ABLE TO DROP A FEW
DEGREES...THE THREAT FOR FOG BECOMES HIGHER...ALTHOUGH FORECAST
SOUNDINGS GENERALLY DO NOT LOOK TO SUPPORT ANYTHING DENSE GIVEN
THE ALREADY PRESENT LOW CLOUD DECK.
RAIN SHOULD BEGIN TO DEVELOP WITHIN GREATER MOISTURE ADVECTION AND
CONVERGENCE ACROSS CENTRAL ILLINOIS LATER TONIGHT AND SPREAD
NORTHWARD INTO THE FORECAST AREA. GREATER INTENSITY LOOKS TO BE
SEEN BEYOND TONIGHT INTO SUNDAY.
MTF
&&
.LONG TERM...
315 AM CST
SUNDAY ONWARD...
SUNDAY THE REGION WILL REMAIN IN A BROAD WARM AIR ADVECTION REGIME
AHEAD OF A PAIR OF TROUGHS APPROACHING FROM THE WEST. BROAD DEEP
SOUTHERLY FLOW WILL CONTINUE TO USHER WARMER AND INCREASINGLY MORE
MOIST AIR INTO THE REGION. BROAD ISENTROPIC ASCENT WILL CONTINUE TO
SUPPORT AT LEAST SOME OCNL SHOWERS OR DRIZZLE EARLY BEFORE BUILDING
INTO A STEADIER/HEAVIER RAIN LATER IN THE DAY AS THE STRONG SOUTHERN
STREAM SHORTWAVE BEGINS LIFTING NORTHEAST INTO THE REGION. IF EARLY
PORTION OF THE DAY ISNT TOO WET/SHOWERY THEN HIGHS COULD REACH WELL
INTO THE 50S...ESPECIALLY SOUTHERN CWA AS GUIDANCE IS FOCUSING THE
BETTER FORCING NORTH EARLY.
THE NORTHERN AND SOUTHERN STREAK SHORTWAVES ARE STILL PROGGED TO
BEGIN PHASING OVER THE WESTERN GREAT LAKES REGION SUNDAY NIGHT INTO
MONDAY. GUIDANCE CONTINUES TO SUGGEST THAT AN IMPRESSIVELY MOIST AIR
MASS WILL BE TRANSPORTED NORTH INTO THE REGION SUNDAY INTO SUNDAY.
GIVEN THE MAGNITUDE OF FORCING AND AMPLE MOISTURE WITH PWATS NEARING
2 STANDARD DEVIATIONS ABOVE AVERAGE SOME HEALTHY RAINFALL TOTALS
LOOK LIKELY...WITH AMOUNTS SUNDAY INTO SUNDAY NIGHT PROBABLY ENDING
UP CLOSE TO AN INCH. LONG DURATION OF THE PRECIP SHOULD RESULT IN
LITTLE MORE THAN MAYBE SOME MINOR PONDING OF WATER IN LOW SPOTS. RFC
CONTINGENCY FORECASTS DO SUGGEST SOME RESPECTABLE RISES ON AREA
RIVERS...THOUGH IF CURRENT QPF VERIFIES RIVERS WILL REMAIN BELOW
FLOOD STAGE.
AS NORTHERN AND SOUTHERN STREAM SYSTEMS PHASE GUIDANCE IS IN
AGREEMENT THAT THE SURFACE LOW WILL RAPIDLY...AND POTENTIALLY
EXPLOSIVELY IF THE GFS VERIFIES. THERE IS A FAIRLY LARGE SPREAD IN
MODEL GUIDANCE WRT JUST HOW DEEP THE LOW GETS MONDAY AFTERNOON WITH
THE GFS AND SEVERAL OF ITS ENSEMBLE MEMBERS IN THE BETWEEN 961 AND
966MB...WHILE THE ECMWF IS A STILL IMPRESSIVE BUT LESS EXTREME 979.
LACK OF STRONG HIGH PRESSURE IN THE WAKE OF THIS SYSTEM WILL
MITIGATE THE MAGNITUDE OF THE WINDS SOME...BUT LATEST GUIDANCE HAS
TRENDED STRONGER WITH WINDS AGAIN MONDAY. STILL POSSIBLE THERE WILL
BE SOME WAFFLING IN GUIDANCE FOR THE MONDAY TIME RANGE AS MODELS
OFTEN STRUGGLE WITH PHASING SYSTEMS...BUT HAVE FOLLOWED THE TREND
FROM THE DAY SHIFT OF STRONGER WINDS MONDAY WITH GUSTS OF 35-40 MPH
POSSIBLE. IF THE MORE EXTREME GFS MODEL CAMP VERIFIES THEN GUSTS
COULD NEAR ADVISORY CRITERIA MONDAY...A TREND WORTH WATCHING THE
NEXT COUPLE DAYS.
WARM CONVEYOR BELT PRECIP SHOULD GET SHUNTED NORTH OF THE AREA LATER
SUNDAY NIGHT...HOWEVER MODELS SUGGEST THAT DEFORMATION PRECIP COULD
POTENTIALLY WRAP AS FAR SOUTH AS OUR CWA MONDAY...ESPECIALLY
NORTHERN CWA. COLDER AIR WILL COME FLOODING IN ON THE STRONG
WESTERLY WINDS MEANING ANY DEFO PRECIP THAT DOES FALL WOULD
TRANSITION TO SNOW/SNOW SHOWERS MONDAY MORNING. FAR TOO SOON TO HAVE
MUCH CONFIDENCE IN ANY POTENTIAL ACCUMS...BUT BETTER THREAT OF SNOW
ACCUMS LOOKS TO REMAIN NORTH OF THE AREA WITH ACCUMS...IF
ANY...PROBABLY ON THE LIGHT SIDE IN OUR AREA.
STRATUS DECK LIKELY GETS LOCKED IN MONDAY NIGHT TEMPERING THE LOW
TEMPS A BIT BUT MAGNITUDE OF THE COLD AIR ADVECTION SHOULD STILL
ALLOW 20S ACROSS THE AREA. CLOUD COVER MAY STICK AROUND INTO A GOOD
CHUNK OF THE DAY TUESDAY AS THE HEART OF THE COLD AIR MASS TRAVERSES
THE AREA WHICH LOOKS TO RESULT IN VERY LITTLE TEMP RECOVERY FROM
OVERNIGHT LOWS TUESDAY MORNING.
BRIEF AND SOMEWHAT MUTED SHOT OF WARM AIR ADVECTION TUESDAY NIGHT
INTO WEDNESDAY SHOULD OCCUR AHEAD OF A CLIPPER SYSTEM...POTENTIALLY
BRINGING SOME LIGHT SNOW TO THE AREA WEDNESDAY. MEDIUM RANGE
GUIDANCE VARIES WITH RESPECT TO THE TRACK OF THIS SYSTEM SO
MAINTAINING POPS IN THE LOWER END OF THE CHANCE SPECTRUM FOR NOW.
APPEARS LIKELY THAT ANOTHER BLAST OF UNSEASONABLY COLD AIR WILL
FOLLOW THIS CLIPPER IN TIME FOR THANKSGIVING AND THE START OF THE
LONG HOLIDAY WEEKEND WITH HIGHS ONCE AGAIN HEADING BACK DOWN INTO
THE 20S.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* PATCHY IFR CIGS...TO LOW END MVFR CIGS THIS AFTN. LIKELY
TRENDING BACK TOWARDS IFR OVERNIGHT THRU SUN MORNING.
* VSBY WILL HOVER BETWEEN 3-6SM THIS AFTN...POSSIBLY FALLING TO
JUST UNDER 3SM OVERNIGHT THRU SUN MORNING.
* LOW-LEVEL WIND SHEAR DEVELOPING TONIGHT. ARND 2KFT AGL FROM THE
SOUTHWEST NEARING 45KT.
* RAIN SHOWERS DEVELOPING EARLY SUN MORNING...INCREASING IN
COVERAGE CLOSER TO MIDDAY.
BEACHLER
//DISCUSSION...UPDATED 18Z...
VERY MOIST AIR MASS CONTINUES TO FEED NORTHEAST ACROSS NORTHERN
IL/NORTHWEST IN AIRFIELDS THIS AFTERNOON. LITTLE IMPROVEMENT TO
THE CIGS IS EXPECTED...AS A RESULT HAVE HELD CIGS DOWN ARND LOW
END MVFR THIS AFTN AND WILL LIKELY TREND BACK TOWARDS IFR CONDS
OVERNIGHT. GENERALLY EXPECT CIGS ARND 500-900FT AGL THRU THE
OVERNIGHT HOURS. WIND DIR WILL NOT CHANGE MUCH THIS
AFTN/EVE/OVERNIGHT...MAINLY FROM THE SOUTH WITH SPEEDS ALSO NOT
CHANGING MUCH ARND 10-12KT. GIVEN HOW MOIST THE ATMOSPHERE
IS...PERIODIC ROUNDS OF DRIZZLE CAN BE EXPECTED THRU THIS
AFTN/EARLY EVE WILL A LULL LATE THIS EVE. WIND SHEAR IS ALSO
POISED TO DEVELOP THIS EVENING...WITH WINDS ARND 2KFT AGL FROM THE
SOUTHWEST INCREASING TO 40-45KT.
GUIDANCE HAS CONTINUED TO SUGGEST DEVELOPING RAIN SHOWERS AFT
MIDNIGHT/EARLY SUN...SO HAVE HELD ONTO THE MENTION OF LGT RAIN
EARLY SUN. THEN IT APPEARS THE BETER COVERAGE FOR PERHAPS MORE
STEADY RAIN WILL OCCUR LATE SUN MORNING...AND COULD PERSIST THRU
SUN AFTN.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN CIGS HOLDING AT LOW END MVFR...AND MEDIUM
CONFIDENCE ON TIMING CIGS TRENDING BACK TOWARDS IFR.
* HIGH CONFIDENCE IN WIND DIR/SPEED.
* MEDIUM CONFIDENCE IN LOW-LEVEL WIND SHEAR.
* HIGH CONFIDENCE IN DRIZZLE THRU THIS AFTN...THEN MEDIUM
CONFIDENCE IN TIMING OF ENDING THE MENTION OF DRIZZLE.
* HIGH CONFIDENCE IN LIGHT RAIN DEVELOPING EARLY SUN WITH BETTER
COVERAGE LATE SUN MORNING/AFTN. MEDIUM CONFIDENCE IN PRECISE
TIMING OF RAIN IMPACTING TAF SITES.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...RAIN AND IFR PROBABLE. SOUTHERLY WINDS.
MONDAY...CHANCE OF RAIN AND SNOW. STRONG WEST TO SOUTHWEST WINDS.
TUESDAY...MVFR CIGS POSSIBLE. WESTERLY WINDS.
WEDNESDAY...CHANCE OF SNOW AND MVFR. SOUTHWEST WINDS.
THURSDAY...FLURRIES AND MVFR POSSIBLE. NORTHWEST WINDS.
FRIDAY...VFR PROBABLE. SOUTHWEST WINDS.
MTF
&&
.MARINE...
325 AM CST
AN ACTIVE PATTERN OVER THE LAKE IS EXPECTED TO CONTINUE THROUGH THE
UPCOMING WEEK. THE SOUTHWEST GALES SEEN OVER THE LAKE EARLY THIS
MORNING WILL DIMINISH BY MID-LATE MORNING AS THE PRESSURE GRADIENT
SOMEWHAT DIMINISHES. SMALL CRAFT ADVISORY CRITERIA WINDS WILL
CONTINUE THOUGH ACROSS THE IL AND IN NEARSHORES A GOOD PART OF
THE DAY. IT DOES LOOK LIKE WIND SPEEDS WILL DIMINISH TO MORE 15-25
KT FOR THE EVENING AND THEN RE-INCREASE OVERNIGHT WHERE ANOTHER
ADVISORY MAY BE NEEDED.
MODERATELY STRONG SOUTHERLY FLOW WILL CONTINUE SUNDAY IN ADVANCE OF
THE COMPLEX LOW PRESSURE SYSTEM ORGANIZING TO OUR WEST. BY SUNDAY
NIGHT...LOW PRESSURE TRACKING EAST FROM THE NORTHERN PLAINS WILL
BEGIN TO MERGE WITH LOW PRESSURE TRACKING NORTHEAST FROM THE
SOUTHERN PLAINS. MODELS SUGGEST THIS PHASING OF THE TWO LOWS WILL
TAKE PLACE VERY NEAR LAKE MICHIGAN SUNDAY NIGHT WITH A BRIEF PERIOD
OF LIGHTER WINDS NEAR THE CENTER OF THE DEVELOPING STORM SYSTEM. THE
LOW IS FORECAST TO CONTINUE TO RAPIDLY INTENSIFY AS IT MOVES NORTH
MONDAY ALLOWING FOR WESTERLY GALES TO DEVELOP ON THE LAKE IN ITS
WAKE MONDAY. WHILE MODEL AGREE IN THE GENERAL IDEA OF A STRONG LOW
NORTH OF LAKE SUPERIOR BY MIDDAY MONDAY...THEY VARY CONSIDERABLY ON
HOW STRONG THE LOW WILL BE RANGING FROM 28.5 INCHES TO AROUND 29.0
INCHES. IF THE STRONGER SOLUTIONS WERE TO VERIFY THEN A PERIOD OF
STORM FORCE WEST WINDS COULD OCCUR MONDAY...DESPITE THE LACK OF ANY
STRONG HIGH PRESSURE MOVING IN BEHIND THE STORM. IF THE WEAKER
SOLUTIONS PAN OUT THEN LOWER END GALES WOULD STILL LIKELY OCCUR
MONDAY. IT IS LIKELY THAT A GALE WATCH WILL BE ISSUED FOR THE
MONDAY/MONDAY NIGHT TIME FRAME LATER TODAY. WINDS WILL EASE TUESDAY
AND BACK TO SOUTHERLY TUESDAY NIGHT INTO WEDNESDAY AHEAD OF A
CLIPPER BEFORE ANOTHER SHOT OF STRONG AND POSSIBLY GALE FORCE NORTH
OR NORTHWEST WINDS DEVELOP THURSDAY-ISH TIME FRAME.
MTF/IZZI
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 3 PM SATURDAY.
&&
$$
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1154 AM CST Sat Nov 22 2014
.UPDATE...
ISSUED AT 1045 AM CST SAT NOV 22 2014
Will update the forecast for warmer highs this afternoon as
temperatures running warmer, especially in far southeast IL with
Mount Carmel airport up to 61F at 10 am and Lawrenceville at 57F.
Much milder highs in the mid 50s to lower 60s, and mildest day
since Veterans Day Nov 11. Isolated to scattered rain showers to
occur mainly se of the IL river rest of today.
Breaks in low clouds by late morning especially along and south of
a Rushville to Lincoln to Champaign line. Isolated showers were
east of I-57 in eastern IL and lifting ne into Indiana. A few
showers and isolated thunderstorms was over southern MO and these
could lift ne into sw counties and southeast IL by this evening.
SPC has general risk of thunder later today sw of a Quincy to
Springfield to Taylorville line. Breezy ssw winds 12-18 mph and
gusts 18-25 mph bringing milder air in the upper 40s to mid 50s
(coolest readings ne counties), with Mount Carmel airport up to 61F.
Modified 1034 MB Canadian high pressure over the Carolinas and
strong 986 mb low pressure over southeast Alberta was giving a
breezy ssw winds gusting 20-30 mph with much milder and more
moist air over IL today. Streamflow originating from the western
gulf of Mexico has brought dewpoints up into the low to mid 40s
late this morning over central/se IL, a big jump from dewpoints in
the single digits and teens yesterday. Deeper mid level moisture
has shunted off to the east of IL this morning but models return
deeper mid level moisture into areas se of the IL river this
evening, so rain showers should increase in coverage tonight.
&&
.SHORT TERM...(Today)
ISSUED AT 318 AM CST SAT NOV 22 2014
Widespread showers associated with a passing short-wave have now
lifted N/NE into northern Illinois, leaving behind only isolated
showers across the KILX CWA early this morning. Central Illinois
will remain between the departing wave and a much stronger upstream
system today, resulting in limited synoptic lift and overall low
rain chances. In addition, forecast soundings indicate quite a bit
of mid-level drying in the wake of the initial short-wave, so
deep-layer moisture will be lacking for precip development as well.
As a result, have reduced PoPs into the chance category, with mainly
just very light showers or drizzle noted. Brisk southerly winds
will continue to bring warmer air into the region. Based on current
rate of temp rise, have gone at or above the warmest guidance
numbers, with afternoon highs reaching the lower to middle 50s.
&&
.LONG TERM...(Tonight through Friday)
ISSUED AT 318 AM CST SAT NOV 22 2014
After a lull in the precip today, rain chances will once again begin
to increase tonight as another short-wave approaches from the
southwest. After a full day of southerly flow, much deeper moisture
profiles will be in place by the time this particular feature
arrives. As a result, think showers will become likely across the
board overnight.
Main forecast challenges continue to revolve around the phasing of a
vigorous southern stream wave currently evident on water vapor
imagery over northwest Mexico and an approaching northern stream
system. The NAM is the only model that tends to keep the two
systems separate, so have rejected its solution in favor of the
GFS/ECMWF/GEM consensus. End result will be the development of
surface low pressure over Texas Saturday night that lifts
northeastward into Michigan by Monday morning. This particular
track will take the low along/east of the I-57 corridor Sunday
night. After the Saturday night wave exits the region, another
brief lull in precip chances may occur early Sunday morning before
much stronger lift arrives with the main system Sunday afternoon.
Given strong upper dynamics and copious amounts of atmospheric
moisture, will go with categorical PoPs across the board Sunday into
Sunday evening. While the strongest surface-based instability will
remain well to the S/SE from the Tennessee River Valley southward to
the Gulf Coast, think marginal elevated instability in the vicinity
of the deepening low pressure will be sufficient to mention isolated
thunder along/south of I-70 Sunday afternoon and evening.
Once low moves into the southern Great Lakes, strong CAA will spill
into the region late Sunday night into Monday. Most model solutions
agree that the cold air will arrive before the precip has a chance
to depart, so will continue to feature rain/snow-showers mainly
along/west of I-55 late Sunday night into Monday morning before the
low lifts further to the northeast and precip comes to an end.
After that, cold and generally dry weather will be on tap for the
remainder of the week. The only potential fly in the ointment is a
weak clipper system expected to come through by mid-week. Models
still show some minor timing discrepancies: however, signs are
pointing to Wednesday as the most favored time period for light
precip. WAA ahead of the approaching wave will likely boost temps
into the middle to upper 30s across much of the area, with lower 40s
possible far southeast. Given cold air aloft, will carry low chance
PoPs for light snow across the western half of the CWA Wednesday,
then across the east Wednesday night. Due to the weak/fast-moving
nature of this system and the marginally warm temps, am not
expecting much in the way of snow accumulation, with perhaps a
couple tenths of an inch at best. Thanksgiving Day still looks
cold and dry with highs ranging from the upper 20s north to the
middle 30s far south.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 1155 AM CST SAT NOV 22 2014
MVFR ceilings at PIA and BMI most of this morning (just lifted to
VFR at PIA) while VFR ceilings along I-72 at midday. Meanwhile
isolated to scattered showers had shifted se of the central IL
airports at late morning. HRRR shows MVFR ceilings 2-3k ft
possible at times over central IL this afternoon especially at PIA
and BMI, and this model shifts these lower ceilings along with fog
further north of central IL this evening. Was more pestimistic
with keeping MVFR ceilings and vsbys around tonight and even lower
IFR ceilings at PIA and BMI Sunday morning. Rain showers to become
more likely later this evening/overnight with best chances
shifting into IL river valley by PIA late tonight and Sunday
morning. Breezy ssw winds 12-17 kts with gusts 18-25 kts into this
evening to veer sse Sunday morning and still gust again to 18-23
kts. Kept LLWS in TAFs again tonight until mid morning Sunday
with 2k ft sw winds of 40 kts.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...07
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...07
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1235 PM EST SAT NOV 22 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 337 AM EST SAT NOV 22 2014
A SERIES OF DISTURBANCES WILL PASS OVER CENTRAL INDIANA DURING THE
FORECAST PERIOD. THE FIRST SYSTEM AND ITS ASSOCIATED WARM FRONT
WILL IMPACT THE FORECAST AREA THROUGH MONDAY NIGHT WITH MAINLY
RAIN. AFTER A LULL IN ACTIVITY...ANOTHER UPPER LEVEL TROUGH WILL
BRING SNOW SHOWERS FOR WEDNESDAY AND THURSDAY WITH A COLDER AIR
MASS IN PLACE.
&&
.NEAR TERM /THIS AFTERNOON/...
ISSUED AT 920 AM EST SAT NOV 22 2014
SURFACE ANALYSIS LATE THIS MORNING SHOWS WARMER...SOUTHERLY FLOW
IN PLACE ACROSS INDIANA AS HIGH PRESSURE WAS CENTERED OVER THE
CAROLINAS. ABUNDANT CLOUD COVER WAS STREAMING NORTHEAST FROM THE
SOUTHERN PLAINS AND INTO THE OHIO VALLEY. HRRR CONTINUES TO
SUGGEST SCT LIGHT RAIN SHOWERS CONTINUING THROUGH THE DAY...BUILD
LESSENING IN COVERAGE BY LATE THIS AFTERNOON. UPPER SUPPORT IS
MINIMAL. 290K ISENTROPIC SURFACE CONTINUES TO SHOW BROAD
ISENTROPIC LIFT AMID ONGOING WARM AIR ADVECTION. SPECIFIC
HUMIDITIES CONTINUE TO RUN OVER 6 G/KG. THUS WILL KEEP ONGOING LOW
CHANCES FOR PRECIP THIS AFTERNOON AS COVER LOOKS TO REMAIN
SPOTTY. ONGOING FORECAST HANDLES THIS WELL AND ONLY MINOR CHANGES
HAVE BEEN MADE.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
ISSUED AT 405 AM EST SAT NOV 22 2014
THE MAIN FOCUS OF THE SHORT TERM PERIOD WILL BE THE HIGH PRECIP
CHANCES AS A SURFACE LOW TRAVERSES THE AREA.
PRECIP CHANCES WILL ONLY CONTINUE TO INCREASE TONIGHT THROUGH
TOMORROW AS SURFACE LOW PROVIDES BETTER LIFT. AS A RESULT...WILL
GO WITH POPS OF 100 PERCENT STARTING TOMORROW AFTERNOON THROUGH
TOMORROW NIGHT.
AS SYSTEM MOVES NORTH INTO THE GREAT LAKES REGION ON
MONDAY...PRECIP CHANCES WILL DECREASE FROM WEST TO EAST ACROSS
CENTRAL INDIANA...ALMOST COMPLETELY OUT OF THE AREA BY TUE 00Z. A
FEW LIGHT SNOW SHOWERS CAN BE EXPECTED OVER THE NORTHERN COUNTIES
SINCE COLDER AIR WILL HAVE ALREADY FILTERED IN BY THAT POINT...BUT
NO ACCUMULATIONS ARE EXPECTED SINCE MOST OF THE MOISTURE WILL HAVE
ALREADY EXITED THE AREA.
THE ABOVE NORMAL TEMPERATURES WILL CONTINUE THROUGH THE WEEKEND WITH
HIGHS TOPPING OFF IN THE 50S ON SUNDAY. BUT THE COOLING TREND WILL
COMMENCE ON MONDAY AS HIGHS ONLY TOP OFF IN THE 40S OVER THE WESTERN
TIER OF COUNTIES.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
ISSUED AT 337 AM EST SAT NOV 22 2014
MODELS INDICATE A BROAD UPPER TROUGH WILL BE ACROSS CENTRAL AND
EASTERN CANADA AS WELL AS THE UPPER MIDWEST AND GREAT LAKES. A
SURFACE LOW OVER SOUTHEAST CANADA TUESDAY WILL MOVE ON TO THE EAST
AND HIGH PRESSURE WILL MOVE EAST ACROSS OUR REGION TUESDAY NIGHT AND
EARLY WEDNESDAY. ANOTHER AREA OF LOW PRESSURE WILL AFFECT OUR
WEATHER AS IT MOVES EAST ACROSS THE NORTHERN PORTIONS OF ILLINOIS
AND INDIANA WEDNESDAY NIGHT AND THURSDAY. WILL MENTION A SLIGHT
CHANCE OF SNOW NORTHWEST LATE WEDNESDAY AND A CHANCE OF SNOW NORTH
AND CENTRAL AND A SLIGHT CHANCE OF SNOW OR MIXED PRECIPITATION FAR
SOUTH. DRY WEATHER WILL RETURN FRIDAY AS HIGH PRESSURE OVER THE
UPPER MIDWEST BUILDS OUR WAY.
IN REGARDS TO TEMPERATURES...MODELS HAVE TRENDED A LITTLE WARMER
LATE WEDNESDAY AND THURSDAY. HOWEVER THE GFS IS OVERDOING THIS AS
IT KEEPS THE ARCTIC AIR BOTTLED ACROSS SOUTHERN CANADA AND GREAT
LAKES. THE 00Z EURO AND GEMNH MODELS PULL MORE OF THIS COLD AIR
SOUTH INTO OUR ALL REGION ESPECIALLY THURSDAY. WITH THE GFS BEING SO
WARM...CUT MOS BLEND TEMPERATURES A LITTLE AROUND THURSDAY.
OTHERWISE...ONLY MINOR TWEAKS MADE TO TEMPERATURES IN MOST OTHER
PERIODS.
&&
.AVIATION /DISCUSSION FOR 221800Z TAF ISSUANCE/...
ISSUED AT 1234 PM EST SAT NOV 22 2014
VFR CONDITIONS WITH SCATTERED VERY LIGHT SHOWERS AND LOW LEVEL WIND
SHEAR SHOULD CONTINUE THROUGH THE AFTERNOON. LOW LEVEL JET SHOULD
WEAKEN SOME LATER THIS AFTERNOON ENOUGH TO DROP MENTION OF LLWS BY
AROUND 23Z. TIME HEIGHTS SHOW LOW LEVEL MOISTURE INCREASING DURING
THE OVERNIGHT AND EXPECT TO SEE MVFR CLOUD DECK DEVELOP BETWEEN
AROUND 9-12Z AND MORE RAIN TO DEVELOP AFTER THAT. RIGHT NOW WILL GO
WITH LOW END MVFR BUT WILL NEED TO WATCH FOR LOWER CEILINGS AS
SYSTEM APPROACHES.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...TDUD
NEAR TERM...PUMA
SHORT TERM...TDUD
LONG TERM....JH
AVIATION...CP
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AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
255 PM EST SAT NOV 22 2014
.UPDATE...
ISSUED AT 150 PM EST SAT NOV 22 2014
FRESHENED UP TEMPS WITH LATEST OBS IN MANY LOCATIONS IN THE UPPER 50S
TO LOWER 60S THIS AFTERNOON. OTHER THAN THAT NO MAJOR CHANGES PLANNED
THIS UPDATE.
UPDATE ISSUED AT 1050 AM EST SAT NOV 22 2014
TEMPERATURES IN THE NORTHERN PART OF THE CWA NEAR THE BLUEGRASS
CONTINUE TO WARM INTO THE LOWER 50S WHILE A FEW VALLEY SPOTS ACROSS
THE CWA CONTINUE TO STRUGGLE UP INTO THE LOWER 40S. THEREFORE DID
FRESHEN TEMPS/DEWPOINTS ACROSS THE REGION TO MATCH CURRENT
OBS. GIVEN ABUNDANT SUNSHINE AND RETURN FLOW FROM SURFACE HIGH
TEMPERATURES ARE STILL EXPECTED TO REACH THE UPPER 50S TO LOWER 60S
AREA WIDE TODAY. WSR-88D RADAR CONTINUES TO INDICATE SOME SPRINKLES
ACROSS THE FAR NORTH CWA/BLUEGRASS REGIONS THIS MORNING. THESE
RETURNS HAVE BEEN LIGHT IN MOST CASES AND EXPECT MUCH OF THE RETURNS
SEEN ON RADAR ARE PROBABLY NOT REACHING THE GROUND. HOWEVER DID OPT
TO KEEP SPRINKLES JUST A BIT LONGER IN THE NORTHERN TIP OF THE CWA
THIS MORNING INTO AROUND THE NOON TIME FRAME GIVEN THAT REGION WOULD
LIKELY SEE THE HIGHEST RADAR RETURNS.
UPDATE ISSUED AT 747 AM EST SAT NOV 22 2014
TEMPERATURES CONTINUE TO WARM ACROSS THE AREA...ESPECIALLY OUT IN THE
WEST...WHERE EKQ IS CURRENTLY REPORTING IN THE MID 40S. FURTHER
EAST...VALLEYS STILL REMAIN DECOUPLED...WITH THE PAINTSVILLE MESONET
STILL REPORTING 20 DEGREES AND OUR COOP IN INEZ REPORTING AT 21
DEGREES. THE RADAR CONTINUES TO SHOW LIGHT RETURNS SKIMMING BY THE
BLUEGRASS COUNTIES. FORTUNATELY...TEMPERATURES HAVE WARMED ABOVE
FREEZING FOR THE MAJORITY OF THE AREA...AND THE LATEST RADAR AND
SHORT RANGE MODEL GUIDANCE CONTINUES TO SUGGEST ONLY SPRINKLES FOR
THE NEXT FEW HOURS. AS SUCH...HAVE MERELY FRESHENED UP THE
HOURLY TEMPERATURE AND DEW POINT TRENDS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 337 AM EST SAT NOV 22 2014
THE LATEST SURFACE MAP FEATURES A LARGE AREA OF HIGH PRESSURE ACROSS
THE EASTERN CONUS...WITH LOW PRESSURE CRUISING THROUGH ONTARIO.
ALOFT...FAIRLY PROGRESSIVE FLOW IS IN PLACE...WITH A WEAKER SHORT
WAVE MOVING THROUGH THE OHIO VALLEY. A STRONGER VORT IS ROTATING
ALONG NORTHERN MEXICO...WHILE ADDITIONAL SHORT WAVE ENERGY IS MOVING
ACROSS THE PACIFIC NORTHWEST.
ANOTHER CHILLY NIGHT HAS BEEN ON TAP FOR EASTERN KENTUCKY...ALTHOUGH
NOT AS COLD AS LAST NIGHT. THERE ARE A FEW VALLEYS IN THE FAR EAST
REMAINING IN THE UPPER TEENS...WHILE LOW TO MID 20S ARE COMMON IN THE
BROADER VALLEYS. RIDGETOPS ARE IN THE 30S THANKS TO LIGHT SOUTH TO
SOUTHEAST WINDS. A DECENT 850 MB JET HAS DEVELOPED ACROSS THE OHIO VALLEY
OVERNIGHT...WITH LIGHT PRECIPITATION BREAKING OUT ACROSS MOST OF
INDIANA AND DOWN INTO WESTERN KENTUCKY. THE LATEST HRRR MAY SUPPORT A
FEW SPRINKLES ACROSS THE I-64 CORRIDOR TOWARDS DAWN...HOWEVER GIVEN
THE DRY AIR IN PLACE CHANCES OF MEASURABLE PRECIPITATION LOOK LOW.
ONCE THE SPRINKLES SKIRT BY TO THE NORTH EARLY THIS MORNING...DRY
CONDITIONS WILL REMAIN IN PLACE THANKS TO LOW LEVEL SOUTHEASTERLY
FLOW. HIGHS TODAY WILL APPROACH THE 60 DEGREE MARK IN
PLACES...TEMPERATURES THAT WE HAVE NOT SEEN IN ABOUT A WEEK AND A
HALF. MEANWHILE...NORTHERN STREAM SHORT WAVE ENERGY WILL TRAVERSE THE
U.S./CANADIAN BORDER...WHILE THE SOUTHERN STREAM VORT CONTINUES TO
SLIDE EAST. THE VORT WILL THEN SWING MORE NORTHEAST...REACHING THE
TENNESSEE VALLEY BY LATE IN THE DAY ON SUNDAY. THIS WILL RESULT IN
SURFACE LOW PRESSURE ORGANIZING ACROSS THE PLAINS...EVENTUALLY
CONGLOMERATING ACROSS THE OHIO VALLEY LATE IN THE PERIOD.
EASTERN KENTUCKY WILL ENJOY A MILDER NIGHT TONIGHT...AS WARM AIR
ADVECTION CONTINUES OUT AHEAD OF THE APPROACHING SYSTEM FROM THE
WEST. LOWS WILL BOTTOM OUT IN THE LOWER 30S IN THE MORE SHELTERED
VALLEYS IN THE EAST...WHILE OTHER LOCATIONS WILL SEE UPPER 30S AND
LOWER 40S. A WARM FRONT/MID-LEVEL SHORT WAVE WILL APPROACH THE AREA
FROM THE SOUTHWEST ON SUNDAY...WITH WIDESPREAD SHOWER ACTIVITY
BREAKING OUT ACROSS EASTERN KENTUCKY IN THE AFTERNOON. HAVE CONTINUED
TO DOWNPLAY THE QPF AMOUNTS IN THE FAR EAST WITH DOWNSLOPE FLOW IN
PLACE. DESPITE THE SHOWERS MOVING IN...HIGHS WILL MAKE IT BACK INTO
THE UPPER 50S AND LOWER 60S.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 255 PM EST SAT NOV 22 2014
THE MODELS ARE IN REASONABLE AGREEMENT ALOFT AT THE START OF THE
EXTENDED PORTION OF THE FORECAST AND CARRY ON THAT WAY THROUGH
TUESDAY BEFORE THE ECMWF BREAKS RANK. IT TAKES A STRONG SHORTWAVE
FROM THE NORTHERN PLAINS INTO THE LOWER OHIO VALLEY IN CONTRAST TO
THE GFS VERSION THAT KEEP ITS ENERGY COINCIDENT WITH THE MAIN TROUGH
SWEEPING THROUGH THE AREA ON TUESDAY. THE GEM SORT OF SPLITS THE
DIFFERENCE WITH A SLOWER MAIN TROUGH BUT WITH LOWER HEIGHTS THROUGH
THE UPPER MIDWEST AND NORTHERN PLAINS. BY FRIDAY THE MODELS ARE QUITE
OUT OF SYNC WITH THE GEM/S LOW HEIGHTS HANGING BACK OVER THE MID
SECTION OF THE NATION WHILE THE ECMWF BODILY MOVES ITS SECONDARY
TROUGH TO THE EAST COAST AND THE GFS HAS A FLATTER TROUGH OVER THE
OHIO VALLEY. INTERESTINGLY ENOUGH THE GFS AND ECMWF DO GET BACK IN
STEP WITH EACH OTHER FOR THE WEEKEND AS THEY BOTH DEPICT NEARLY FLAT
NORTHWEST FLOW OVER THE AREA ALONG WITH WEAK ENERGY APPROACHING FROM
THE WEST COAST. GIVEN THE UNCERTAINTY WITH THE MID TO LATE PORTION OF
THE EXTENDED WILL FAVOR A BLENDED SOLUTION FOR WEATHER DETAILS.
SENSIBLE WEATHER WILL FEATURE A GRADUAL COOL DOWN IN THE WAKE OF A
LARGE SYSTEM ROLLING INTO QUEBEC. A MOSTLY DRY COLD FRONT DOES CROSS
THE STATE ON MONDAY WITH A BKN BAND OF SHOWERS EXPECTED. THE DEEPER
MOISTURE FROM THIS SYSTEM/S WRAP AROUND SHOULD STAY OFF TO THE NORTH
AND EAST LEAVING MAINLY JUST SOME EXTRA CLOUDS AND LOW POPS BEHIND.
THE ECMWF AND GFS TAKE A WAVE UP THE SOUTHEAST COAST EARLY WEDNESDAY
BRUSHING BY EAST KENTUCKY TO THE EAST. AT THIS POINT...CANNOT RULE
OUT A FEW STRAY SHOWERS OF RAIN OR SNOW...MAINLY AT THE HIGHER
ELEVATIONS...SLIPPING INTO THE CWA AS THE LOW PASSES. BOTH THE GFS
AND ECMWF THEN TAKE A SFC LOW THROUGH THE GREAT LAKES WITH THE FORMER
MORE NORTHEAST AND STRONGER THAN THE LATTER. IT IS IN THE WAKE OF
THIS LOW...AND ITS RE-ENFORCING COLD FRONT...THAT THE COLDER AIR
FINALLY SURGES INTO EAST KENTUCKY...IN THE ECMWF...ALONG WITH SOME
UPSLOPE AND GREAT LAKES ENHANCED PCPN. THE GFS KEEPS THE WORST OF THE
COLD AIR TO THE NORTH OF THE AREA THROUGH THE END OF THE WEEK ALONG
WITH JUST SPOTTY PCPN CHANCES ALONG THE NEARBY BOUNDARY. SPLITTING
THE DIFFERENCE HERE MAKES FOR A COMPLICATED FORECAST...BUT THAT IS
THE BEST WE CAN DO WITHOUT A MODEL BREAK TOWARD ONE SOLUTION OR
THE OTHER. FOR THE START OF THE WEEKEND...HIGH PRESSURE WILL MOST
LIKELY KEEP THE PCPN AT BAY...GENERALLY OFF TO THE NORTH AND WEST BUT
IT DOES START TO PULL OFF TO THE SOUTHEAST AND MAY ALLOW SOMETHING TO
SLIP IN LATE.
THE CR GRID LOAD PROVIDED A GOOD START THROUGH THE EXTENDED FORECAST
WITH CHANGES MAINLY MADE TO FINE TUNE THE POPS EARLY ON. DID ALSO
MAKE SOME MINOR CHANGES TO THE LOWS BASED ON TERRAIN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 747 AM EST SAT NOV 22 2014
EXPECT VFR CONDITIONS TO HOLD ON THROUGH THE PERIOD. SOME PASSING LOW
CLOUDS BETWEEN 4 AND 5K FEET AGL WILL BE SEEN THIS MORNING...AND THEN
ONCE AGAIN BETWEEN 06 AND 12Z. OTHERWISE MOST CLOUD COVER WILL BE AT
OR ABOVE 10K FEET AGL. WINDS WILL REMAIN OUT OF THE SOUTH AND
SOUTHEAST...AT OR AROUND 5 KTS THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...GEOGERIAN
LONG TERM...GREIF
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS JACKSON KY
153 PM EST SAT NOV 22 2014
.UPDATE...
ISSUED AT 150 PM EST SAT NOV 22 2014
FRESHENED UP TEMPS WITH LATEST OBS IN MANY LOCATIONS IN THE UPPER 50S
TO LOWER 60S THIS AFTERNOON. OTHER THAN THAT NO MAJOR CHANGES PLANNED
THIS UPDATE.
UPDATE ISSUED AT 1050 AM EST SAT NOV 22 2014
TEMPERATURES IN THE NORTHERN PART OF THE CWA NEAR THE BLUEGRASS
CONTINUE TO WARM INTO THE LOWER 50S WHILE A FEW VALLEY SPOTS ACROSS
THE CWA CONTINUE TO STRUGGLE UP INTO THE LOWER 40S. THEREFORE DID
FRESHEN TEMPS/DEWPOINTS ACROSS THE REGION TO MATCH CURRENT
OBS. GIVEN ABUNDANT SUNSHINE AND RETURN FLOW FROM SURFACE HIGH
TEMPERATURES ARE STILL EXPECTED TO REACH THE UPPER 50S TO LOWER 60S
AREA WIDE TODAY. WSR-88D RADAR CONTINUES TO INDICATE SOME SPRINKLES
ACROSS THE FAR NORTH CWA/BLUEGRASS REGIONS THIS MORNING. THESE
RETURNS HAVE BEEN LIGHT IN MOST CASES AND EXPECT MUCH OF THE RETURNS
SEEN ON RADAR ARE PROBABLY NOT REACHING THE GROUND. HOWEVER DID OPT
TO KEEP SPRINKLES JUST A BIT LONGER IN THE NORTHERN TIP OF THE CWA
THIS MORNING INTO AROUND THE NOON TIME FRAME GIVEN THAT REGION WOULD
LIKELY SEE THE HIGHEST RADAR RETURNS.
UPDATE ISSUED AT 747 AM EST SAT NOV 22 2014
TEMPERATURES CONTINUE TO WARM ACROSS THE AREA...ESPECIALLY OUT IN THE
WEST...WHERE EKQ IS CURRENTLY REPORTING IN THE MID 40S. FURTHER
EAST...VALLEYS STILL REMAIN DECOUPLED...WITH THE PAINTSVILLE MESONET
STILL REPORTING 20 DEGREES AND OUR COOP IN INEZ REPORTING AT 21
DEGREES. THE RADAR CONTINUES TO SHOW LIGHT RETURNS SKIMMING BY THE
BLUEGRASS COUNTIES. FORTUNATELY...TEMPERATURES HAVE WARMED ABOVE
FREEZING FOR THE MAJORITY OF THE AREA...AND THE LATEST RADAR AND
SHORT RANGE MODEL GUIDANCE CONTINUES TO SUGGEST ONLY SPRINKLES FOR
THE NEXT FEW HOURS. AS SUCH...HAVE MERELY FRESHENED UP THE
HOURLY TEMPERATURE AND DEW POINT TRENDS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 337 AM EST SAT NOV 22 2014
THE LATEST SURFACE MAP FEATURES A LARGE AREA OF HIGH PRESSURE ACROSS
THE EASTERN CONUS...WITH LOW PRESSURE CRUISING THROUGH ONTARIO.
ALOFT...FAIRLY PROGRESSIVE FLOW IS IN PLACE...WITH A WEAKER SHORT
WAVE MOVING THROUGH THE OHIO VALLEY. A STRONGER VORT IS ROTATING
ALONG NORTHERN MEXICO...WHILE ADDITIONAL SHORT WAVE ENERGY IS MOVING
ACROSS THE PACIFIC NORTHWEST.
ANOTHER CHILLY NIGHT HAS BEEN ON TAP FOR EASTERN KENTUCKY...ALTHOUGH
NOT AS COLD AS LAST NIGHT. THERE ARE A FEW VALLEYS IN THE FAR EAST
REMAINING IN THE UPPER TEENS...WHILE LOW TO MID 20S ARE COMMON IN THE
BROADER VALLEYS. RIDGETOPS ARE IN THE 30S THANKS TO LIGHT SOUTH TO
SOUTHEAST WINDS. A DECENT 850 MB JET HAS DEVELOPED ACROSS THE OHIO VALLEY
OVERNIGHT...WITH LIGHT PRECIPITATION BREAKING OUT ACROSS MOST OF
INDIANA AND DOWN INTO WESTERN KENTUCKY. THE LATEST HRRR MAY SUPPORT A
FEW SPRINKLES ACROSS THE I-64 CORRIDOR TOWARDS DAWN...HOWEVER GIVEN
THE DRY AIR IN PLACE CHANCES OF MEASURABLE PRECIPITATION LOOK LOW.
ONCE THE SPRINKLES SKIRT BY TO THE NORTH EARLY THIS MORNING...DRY
CONDITIONS WILL REMAIN IN PLACE THANKS TO LOW LEVEL SOUTHEASTERLY
FLOW. HIGHS TODAY WILL APPROACH THE 60 DEGREE MARK IN
PLACES...TEMPERATURES THAT WE HAVE NOT SEEN IN ABOUT A WEEK AND A
HALF. MEANWHILE...NORTHERN STREAM SHORT WAVE ENERGY WILL TRAVERSE THE
U.S./CANADIAN BORDER...WHILE THE SOUTHERN STREAM VORT CONTINUES TO
SLIDE EAST. THE VORT WILL THEN SWING MORE NORTHEAST...REACHING THE
TENNESSEE VALLEY BY LATE IN THE DAY ON SUNDAY. THIS WILL RESULT IN
SURFACE LOW PRESSURE ORGANIZING ACROSS THE PLAINS...EVENTUALLY
CONGLOMERATING ACROSS THE OHIO VALLEY LATE IN THE PERIOD.
EASTERN KENTUCKY WILL ENJOY A MILDER NIGHT TONIGHT...AS WARM AIR
ADVECTION CONTINUES OUT AHEAD OF THE APPROACHING SYSTEM FROM THE
WEST. LOWS WILL BOTTOM OUT IN THE LOWER 30S IN THE MORE SHELTERED
VALLEYS IN THE EAST...WHILE OTHER LOCATIONS WILL SEE UPPER 30S AND
LOWER 40S. A WARM FRONT/MID-LEVEL SHORT WAVE WILL APPROACH THE AREA
FROM THE SOUTHWEST ON SUNDAY...WITH WIDESPREAD SHOWER ACTIVITY
BREAKING OUT ACROSS EASTERN KENTUCKY IN THE AFTERNOON. HAVE CONTINUED
TO DOWNPLAY THE QPF AMOUNTS IN THE FAR EAST WITH DOWNSLOPE FLOW IN
PLACE. DESPITE THE SHOWERS MOVING IN...HIGHS WILL MAKE IT BACK INTO
THE UPPER 50S AND LOWER 60S.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 337 AM EST SAT NOV 22 2014
STILL SOME QUESTION AS TO HOW FAST THE TROUGH AXIS SHIFTS TO THE
NORTH SUNDAY EVENING. GFS IS MUCH MORE PROGRESSIVE ON BRINGING THE
DRY SLOT IN QUICKLY SUNDAY EVENING...WHILE THE ECMWF HOLDS IT BACK
EARLY ON. BASIC THINKING IS THAT EVEN IF THE DRY SLOT MOVES IN
FASTER...WE MAY STILL GET DEVELOPMENT INTO THE WARM SECTOR THROUGH
THE NIGHT OR POSSIBLY EVEN SOME MEASURABLE DRIZZLE. THUS...WILL
MAINTAIN HIGH CHANCE TO LIKELY POPS THROUGH THE FIRST HALF OF THE
NIGHT...WITH DRIZZLE BECOMING MORE LIKELY AS THE NIGHT PROGRESSES.
ON MONDAY...A SHARP COLD FRONT WILL PUSH INTO AND CROSS THE AREA.
THIS SHOULD AGAIN BRING HIGHER CHANCES FOR SHOWERS AS IT CROSSES THE
AREA THROUGH EARLY TO MID AFTERNOON. IN THE WAKE OF THE
FRONT...TEMPERATURES WILL TAKE A TUMBLE IN THE AFTERNOON AND EVENING
HOURS. AFTER CLIMBING INTO THE LOW 60S...TEMPERATURES BY THE EVENING
SHOULD SETTLE BACK INTO THE 40S. STILL LOOKS LIKE A WINDY DAY...WITH
925MB WINDS TOPPING 35 KNOTS AS THE FRONT CROSSES THE AREA. ANY
SHOWER ACTIVITY MAY ACTUALLY HELP TO MIX DOWN SOME ISOLATED HIGHER
GUSTS TO 40 OR 45 MPH.
SURFACE HIGH PRESSURE SHOULD MOVE INTO THE OHIO RIVER VALLEY MONDAY
NIGHT WITH DRY WEATHER RETURNING. ATTENTION WILL THEN TURN TO A
POSSIBLE NOREASTER AS AN AREA OF LOW PRESSURE MOVES UP THE EASTERN
US COAST. 00Z ECMWF HAS SHIFTED THE TRACK OF THIS LOW BACK TO THE
WEST...BRINGING MOISTURE INTO THE APPALACHIAN MOUNTAINS. GOING TO
MAINTAIN THE DRY FORECAST...BUT IF THIS SYSTEM TRENDS ANY FARTHER
WEST...MAY NEED TO INSERT SOME POPS BY WEDNESDAY.
MODELS REALLY DIVERGE THEREAFTER AS WE HEAD INTO THANKSGIVING DAY.
GFS BUILDS A RIDGE OVER THE OHIO RIVER VALLEY...SUGGESTING
TEMPERATURES MAY REACH INTO THE 50S...WHILE THE ECMWF DIGS OUT
ANOTHER SHARP TROUGH AND WOULD PUT TEMPERATURES MORE INTO THE 30S
WITH A GOOD CHANCE FOR SNOW. CLEARLY THIS IS A LARGE DIFFERENCE IN
THE MODELS...AND PUTS LOTS OF UNCERTAINTY ON THE THANKSGIVING
FORECAST AND BEYOND. FOR NOW...WILL GO WITH A COMPROMISED
FORECAST...WITH A SLIGHT EDGE TOWARDS THE COLDER ECMWF AS IT HAS
BEEN VERY CONSISTENT ON THE COLDER SOLUTION. WILL ALSO MAINTAIN LOW
POPS WEDNESDAY NIGHT INTO THURSDAY NIGHT...AND GO WITH A MIXTURE OF
RAIN/SNOW THROUGH THIS PERIOD. IT DOES LOOK REGARDLESS OF
THANKSGIVING DAY...MODELS POINT TO A MUCH COLDER END TO THE
WEEK...WITH TEMPERATURES STAYING WELL BELOW NORMAL INTO FRIDAY AND
SATURDAY. WE SHOULD SEE DRIER WEATHER FOR FRIDAY AND SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 747 AM EST SAT NOV 22 2014
EXPECT VFR CONDITIONS TO HOLD ON THROUGH THE PERIOD. SOME PASSING LOW
CLOUDS BETWEEN 4 AND 5K FEET AGL WILL BE SEEN THIS MORNING...AND THEN
ONCE AGAIN BETWEEN 06 AND 12Z. OTHERWISE MOST CLOUD COVER WILL BE AT
OR ABOVE 10K FEET AGL. WINDS WILL REMAIN OUT OF THE SOUTH AND
SOUTHEAST...AT OR AROUND 5 KTS THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...GEOGERIAN
LONG TERM...KAS
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
603 PM EST SAT NOV 22 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 420 PM EST SAT NOV 22 2014
WV IMAGERY AND RUC ANALYSIS INDICATED ZONAL FLOW ACROSS THE NRN
CONUS WITH A STRONG 170 KNOT 250 MB JET MOVING INTO THE PAC NW. A
SHORTWAVE TROUGH WAS MOVING THROUGH SRN SASK AND NRN MT. A VIGOROUS
SRN SHORTWAVE TROUGH WAS LOCATED OVER WRN TEXAS. AT THE SFC...SRLY
FLOW PREVAILED FROM THE GULF TOWARD THE UPPER MS VALLEY AND NRN
LAKES BTWN HIGH PRES OVER THE MID ATLANTIC AND A 984 MB LOW INTO SRN
SASK. WAA HAS PUSHED TEMPS INTO THE MID AND UPPER 30S ACROSS UPPER
MI. ALTHOUGH THE LOW LEVEL MOISTURE THINNED OUT ENOUGH FOR SOME
SUNSHINE THIS AFTERNOON...ESPECIALLY IN DOWNSLOPE LOCATIONS...CLOUDS
OVER NRN WI AND WRN UPPER MI WERE FILLING IN AGAIN ACROSS THE AREA.
TONIGHT...ANY LINGERING DRY LOW LEVEL AIR WILL FILL IN TONIGHT WITH
STRONG LOW LEVEL MOISTURE ADVECTION THIS EVENING. SO...EXPECT BETTER
CHANCES FOR PCPN AS DRIZZLE OR POSSIBLY FREEZING DRIZZLE AS A
SUBSTANTIAL DRY LAYER REMAINS ABOVE 900 MB. SOME FOG WILL BE POSSIBLE
AS WELL AS DEWPOINTS CLIMB TO AROUND FREEZING OR SLIGHTLY ABOVE BY
LATE TONIGHT. EXPECT THE BEST CHANCE FOR DRIZZLE OVER CNTRL UPPER MI
WITH AN UPSLOPE LOW LEVEL WIND COMPONENT SUPPORT...AND OVER THE EAST
CWA WITH ADDED MOISTURE OFF OF LAKE MICHIGAN. TEMPS MAY DROP OFF TO
NEAR FREEZING THIS EVENING AND SLOWLY CLIMB OVERNIGHT.
HOWEVER...SINCE MANY ROAD SURFACES MAY STILL BE BELOW FREEZING...ANY
DRIZZLE THAT FALLS COULD CREATE ICY/SLIPPERY CONDITIONS ON UNTREATED
ROADS.
SUN...EXPECT PCPN CHANCES TO GRADUALLY INCREASE THROUGH THE DAY AS
THE STRONG MOISTURE ADVECTION CONTINUES AND 850-700 MB FGEN
INCREASES. THE GREATEST CHANCE IS EXPECTED OVER THE EAST IN
PROXIMITY TO THE STRONGER DYNAMICS AND BEST MOISTURE. AS THE DRY
LAYER FILLS IN ANY DRIZZLE WILL CHANGE OVER TO RAIN BY MID TO LATE
AFTERNOON. TEMPS WILL CLIMB ABOVE NORMAL INTO THE LOW TO MID 40S.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 426 PM EST SAT NOV 22 2014
QUITE AN ACTIVE START TO THE PERIOD AS THE PHASING OF NORTHERN AND
SOUTHERN ENERGY WILL BE UNDERWAY ACROSS THE UPPER GREAT LAKES.
MODERATE RAINFALL SUNDAY NIGHT WILL GIVE WAY TO A TRANSITION TO SNOW
ON MONDAY AS THE SYSTEM MOVES NE OF THE REGION. THE INGREDIENTS ARE
STILL THERE FOR MODERATE TO POSSIBLY HEAVY SNOW ACROSS AT LEAST THE
WESTERN CWA MONDAY AFTERNOON AND NIGHT. AFTER A REPRIEVE LATE
TUESDAY...A CLIPPER SYSTEM LOOKS TO BRING LIGHT TO POSSIBLY MODERATE
SNOWFALL WEDNESDAY AFTERNOON INTO THANKSGIVING.
SUNDAY NIGHT THROUGH MONDAY NIGHT...FIRST A LOOK AT THE OVERALL
SYNOPTIC PATTERN. TWO POTENT MID-LEVEL SHORTWAVES...ONE TRACKING
EASTWARD OVER THE NORTHERN PLAINS AND THE OTHER MOVING NORTHEASTWARD
NEAR SOUTHERN IL AT 00Z MONDAY WILL BEGIN TO MERGE ACROSS THE UPPER
GREAT LAKES. THE NORTHERN STREAM IS A BIT SLOWER REACHING THE REGION
THAN THE SOUTHERN STREAM...RESULTING IN A BROADENING OF THE TROUGH
BY MONDAY MORNING. MEANWHILE...A DEVELOPING MODEST COUPLED JET
PATTERN WILL DEVELOP OVER THE UPPER GREAT LAKES. THE SOUTHERN WAVE
WILL BE OF MOST INTEREST INITIALLY AS IT INDUCES A RAPIDLY DEEPENING
LOW OVER ILLINOIS AT THE START OF THE PERIOD. WITH THE 12/18Z NAM
RUNS COMING INTO BETTER AGREEMENT WITH THE OTHER MODELS...CONFIDENCE
IS NOW HIGHER REGARDING THE OVERALL EVOLUTION OF THE SYSTEM. THE SFC
LOW IS PROGGED TO TRACK NEAR THE STRAITS OF MACKINAC AROUND 12Z
MONDAY. THE GEM/NAM/ECMWF HINT AT A SLIGHT DEVIATION TO THE LEFT/NW
MONDAY MORNING...WITH THE LOW CROSSING NEAR SAULT STE MARIE. THIS
LOOKS REASONABLE AS THE INFLUENCE OF THE NORTHERN TROUGH APPROACHES.
A LINGERING TROUGH WILL THEN REMAIN ACROSS UPPER MI ON MONDAY AS THE
MID-LEVEL TROUGH AXIS REACHES THE REGION AND THE SFC LOW MOVES TO
JUST SE OF JAMES BAY.
NOW A LOOK AT THE OVERALL PRECIP TYPE AND INTENSITY. MID/UPPER-LEVEL
DYNAMICS AND LOW-LEVEL THERMODYNAMICS SUPPORT MODERATE RAIN ACROSS
MAINLY CENTRAL AND EASTERN UPPER MI SUNDAY NIGHT. THE RIGHT ENTRANCE
OF A DEVELOPING...ALBEIT ANTICYCLONICALLY CURVED...UPPER JET WILL
MAXIMIZE UPPER DIVERGENCE OVER CENTRAL AND EASTERN UPPER MI WHILE
MID-LEVEL Q-VECTOR CONVERGENCE PEAKS OVER NORTHERN LOWER MI.
MEANWHILE...LOW-LEVEL MOISTURE TRANSPORT WILL BE RATHER IMPRESSIVE
ACROSS THE EASTERN CWA...THEN QUICKLY DIMINISH TOWARD THE WESTERN
CWA. A SUFFICIENTLY DEEP LOW-LEVEL WARM LAYER WILL KEEP PRECIP ALL
RAIN ACROSS THE CWA...THOUGH A TRANSITION TO SNOW WILL BE UNDERWAY
LATE SUNDAY NIGHT ACROSS THE WEST AS CAA BEGINS BEHIND THE LOW. ALL
THIS TOGETHER FAVORS MODERATE RAIN ACROSS THE EAST HALF SUNDAY
NIGHT...WITH AN INITIALLY SHARP CUTOFF TO THE WEST BEFORE THE
NORTHERN WAVE APPROACHES OVERNIGHT.
CAA TAKING HOLD ON MONDAY WILL QUICKLY TRANSITION THE RAIN TO SNOW
FROM WEST TO EAST THROUGHOUT THE DAY. THERE ARE SOME INDICATIONS
THAT A LOW-LEVEL WARM LAYER MAY TRY TO WRAP AROUND THE BACK SIDE OF
THE LOW LATE MORNING MORNING INTO THE AFTERNOON. SOME SLEET MAY MIX
IN WITH THE RAIN/SNOW...BUT THE TRANSITION FROM ALL RAIN SNOW SHOULD
NOT TAKE MORE THAN AN HOUR OR TWO. THINK THAT EVEN THE SHORELINE
LOCATIONS SHOULD TRANSITION QUICKLY GIVEN THEN COLDER THAN AVERAGE
LAKE TEMPS. TRANSITION TIMES LOOK TO BE AROUND 09Z FOR IWD...12Z FOR
A LINE FROM HOUGHTON TO IRON RIVER...AND 15Z FOR A LINE FROM
MARQUETTE TO IMT. BY 21Z...ALL BUT POSSIBLY LUCE COUNTY SHOULD
TRANSITION TO SNOW.
A FAIRLY IMPRESSIVE MID-LEVEL FGEN/DEFORMATION ZONE WILL SET UP OVER
THE WESTERN CWA BY MONDAY AFTERNOON. WITH SOME SNOWFLAKE FRACTURING
FROM THE HIGHER WINDS AND THE MAX LIFT INITIALLY OCCURRING AT TEMPS
JUST A BIT WARMER THAN THE DGZ...SNOW RATIOS MAY REMAIN LOW /10 TO
1/ THROUGH MONDAY MORNING. AS TEMPS CONTINUE TO FALL IN TO THE
AFTERNOON SNOW RATIOS WILL BE ON THE RISE ACROSS THE WEST. LOW-LEVEL
WINDS AVERAGING OUT THE NORTH COMBINED WITH LAKE-850MB DELTA TEMPS
SURPASSING 10C SUPPORT DECENT LAKE-ENHANCEMENT FOR THE NORTH WIND
SNOW BELTS THROUGHOUT MONDAY. THIS PATTERN WILL CONTINUE INTO MONDAY
EVENING AS THE CONSOLIDATED TROUGH SLOWS OVER THE AREA AND KEEPS A
SFC TROUGH EXTENDED ACROSS MUCH OF EASTERN UPPER MI. ON TOP OF THE
SNOW...THE CAA WITH A STRONG WNW TO ESE ISALLOBARIC COMPONENT FROM
THE RAPIDLY DEEPENING LOW WILL YIELD A QUICK INCREASE IN WIND FROM
THE N/NNW.
WHEN ALL IS SAID AND DONE...SNOWFALL MONDAY AND MONDAY NIGHT IS
EXPECTED TO BE 6 TO 10 INCHES BASICALLY NORTH OF M-28 AND WEST OF
MARQUETTE. ELSEWHERE ACROSS THE CWA...2-4 INCHES IS EXPECTED.
HOWEVER...HIGHER AMOUNTS OF UP TO 6 INCHES WILL BE POSSIBLE FOR THE
NNW WIND SNOW BELTS FROM SHOT POINT TO GRAND MARAIS. THREW AROUND
THE IDEA OF A WINTER STORM WATCH FOR THE NW HALF...BUT DECIDED
AGAINST IT GIVEN SOME DETAILS IN QPF AND PLACEMENT OF FORCING THAT
NEED TO BE IRONED OUT. HOWEVER...WINTER WX ADVISORY CRITERIA SHOULD
BE MET. HAVE OPTED TO ISSUE A SPECIAL WX STATEMENT AT THIS TIME TO
HIGHLIGHT THE POTENTIAL...BUT ALSO NOTE THE UNCERTAINTY IN AMOUNTS.
MAIN IMPACTS WILL BE RATHER SLUSHY ROADS IN THE AFTERNOON FOLLOWED
BY BLOWING AND DRIFTING OF THE SNOW OVERNIGHT AS SNOW RATIOS
INCREASE.
TUESDAY THROUGH WEDNESDAY NIGHT...WEAK MID-LEVEL RIDGING...LOW-LEVEL
WAA AND INVERSION HEIGHTS FALLING BELOW 3KFT WILL PUT A QUICK END TO
THE LES FROM WEST TO EAST THROUGHOUT THE DAY. A CLIPPER SHORTWAVE
WILL TRACK SE INTO THE UPPER MS VALLEY LATE TUESDAY. THE SHORTWAVE
LOOKS TO GET CAUGHT UP IN A LARGER-SCALE TROUGH OVER HUDSON
BAY...ULTIMATELY SLOWING ITS PROGRESSING AND SHIFTING IT TO A ENE
TRACK. WHERE THIS TAKES PLACE WILL BE CRUCIAL FOR DETERMINING SNOW
PROBABILITY/AMOUNTS FOR THE CWA. THE GFS IS THE FASTEST...BRINGING
WIDESPREAD ACCUMULATING SNOW TO THE AREA LATE TUESDAY NIGHT INTO
WEDNESDAY AFTERNOON. THE ECMWF TAKES AN INITIALLY MORE AGGRESSIVE
EVOLUTION...RESULTING THE THE TROUGH DIGGING FARTHER SOUTHEAST
BEFORE PIVOTING ACROSS SOUTHERN LAKE/LOWER MI. WITH THIS
SCENARIO...MOST OF THE SNOW HOLDS OFF UNTIL WEDNESDAY NIGHT. THE GEM
FOLLOWS A SOLUTION IN THE MIDDLE...BUT LEANS MORE IN LINE WITH THE
GFS. ATTM...CANNOT REALLY PIN DOWN AMOUNTS AND EXACT TIMING...THOUGH
THE PROSPECTS FOR SEVERAL INCHES OF ACCUMULATING SNOW SOMETIME LATE
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT ARE GROWING.
THANKSGIVING...DEPENDING ON WHAT MODEL SOLUTION PANS
OUT...WIDESPREAD SNOW MAY LINGER THROUGH THE MORNING OR END BEFORE
DAYBREAK. EITHER WAY...CAA BEHIND THE CLIPPER SHOULD YIELD LES FOR
THE N/NNW WIND BELTS DURING THE DAY. IT STILL LOOKS COLD...WITH
TEMPS MORE IN LINE WITH CHRISTMAS RATHER THAN THANKSGIVING.
HOWEVER...WITH THE SLOWER SOLUTION...THE ECMWF HAS A HARDER TIME
BRINGING THE COLDEST AIR INTO THE REGION.
FRIDAY AND SATURDAY...LONG RANGE MODELS HAVE BACKED OFF SOMEWHERE ON
A TRANSITION TO A MORE ZONAL AND MILD PATTERN BEGINNING FRIDAY AND
DELAY IT UNTIL LATE IN THE WEEKEND. THE OVERALL PATTERN LOOKS QUIET
BESIDE SOME LES FOR THE WNW WIND SNOW BELTS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 603 PM EST SAT NOV 22 2014
LOW CLOUDS ARE THE MAIN FORECAST ISSUE INTO SUNDAY. CONTINUING
MOISTURE FLOWING INTO THE AREA SHOULD RESULT IN LOWERING OF CIGS
TONIGHT. BASED ON UPSTREAM CIGS THIS MORNING OVER IA/MN/WI...EXPECT
CIGS TO FALL TO IFR LATE TONIGHT...OR EVEN LIFR...AS THE MOIST
LOW-LEVELS WILL BE ONLY BE ADDED TO BY ADDITIONAL MOISTURE AND
HELPED ALONG BY DEVELOPING UPSLOPE FLOW AT KCMX AND KSAW. AT THESE
SITES....PROBABLY WILL SEE DRIZZLE AND FOG AS WELL WITH VSBY LIKELY
REACHING IFR LATE TONIGHT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 420 PM EST SAT NOV 22 2014
SOUTH WINDS WILL INCREASE ON SUNDAY...ESPECIALLY OVER EASTERN
SECTIONS...BUT SHOULD REMAIN 30 KTS OR LESS. WINDS WILL BE VARIABLE
SUNDAY NIGHT AS TROUGH CROSSES LAKE SUPERIOR. A DEEPENING LOW WILL MOVE
TO EAST OF LAKE SUPERIOR ON MONDAY. NORTHERLY WINDS WILL INCREASE TO
GALES 40-45 KTS MONDAY AFTN INTO MONDAY NIGHT. WINDS DIMINISH TO 25
KTS OR LESS LATER TUESDAY INTO WEDNESDAY...THEN INCREASE TO 30 KTS
ON THURSDAY AS COLD AIR POURS ACROSS LAKE SUPERIOR BETWEEN HIGH PRESSURE
BUILDING OVER THE NORTHERN PLAINS AND LOW PRESSURE CROSSING THE
LOWER GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM MONDAY AFTERNOON THROUGH LATE MONDAY NIGHT FOR
LSZ248>250-265-266.
GALE WATCH FROM MONDAY MORNING THROUGH LATE MONDAY NIGHT FOR
LSZ242>245-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KLUBER
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
427 PM EST SAT NOV 22 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 420 PM EST SAT NOV 22 2014
WV IMAGERY AND RUC ANALYSIS INDICATED ZONAL FLOW ACROSS THE NRN
CONUS WITH A STRONG 170 KNOT 250 MB JET MOVING INTO THE PAC NW. A
SHORTWAVE TROUGH WAS MOVING THROUGH SRN SASK AND NRN MT. A VIGOROUS
SRN SHORTWAVE TROUGH WAS LOCATED OVER WRN TEXAS. AT THE SFC...SRLY
FLOW PREVAILED FROM THE GULF TOWARD THE UPPER MS VALLEY AND NRN
LAKES BTWN HIGH PRES OVER THE MID ATLANTIC AND A 984 MB LOW INTO SRN
SASK. WAA HAS PUSHED TEMPS INTO THE MID AND UPPER 30S ACROSS UPPER
MI. ALTHOUGH THE LOW LEVEL MOISTURE THINNED OUT ENOUGH FOR SOME
SUNSHINE THIS AFTERNOON...ESPECIALLY IN DOWNSLOPE LOCATIONS...CLOUDS
OVER NRN WI AND WRN UPPER MI WERE FILLING IN AGAIN ACROSS THE AREA.
TONIGHT...ANY LINGERING DRY LOW LEVEL AIR WILL FILL IN TONIGHT WITH
STRONG LOW LEVEL MOISTURE ADVECTION THIS EVENING. SO...EXPECT BETTER
CHANCES FOR PCPN AS DRIZZLE OR POSSIBLY FREEZING DRIZZLE AS A
SUBSTANTIAL DRY LAYER REMAINS ABOVE 900 MB. SOME FOG WILL BE POSSIBLE
AS WELL AS DEWPOINTS CLIMB TO AROUND FREEZING OR SLIGHTLY ABOVE BY
LATE TONIGHT. EXPECT THE BEST CHANCE FOR DRIZZLE OVER CNTRL UPPER MI
WITH AN UPSLOPE LOW LEVEL WIND COMPONENT SUPPORT...AND OVER THE EAST
CWA WITH ADDED MOISTURE OFF OF LAKE MICHIGAN. TEMPS MAY DROP OFF TO
NEAR FREEZING THIS EVENING AND SLOWLY CLIMB OVERNIGHT.
HOWEVER...SINCE MANY ROAD SURFACES MAY STILL BE BELOW FREEZING...ANY
DRIZZLE THAT FALLS COULD CREATE ICY/SLIPPERY CONDITIONS ON UNTREATED
ROADS.
SUN...EXPECT PCPN CHANCES TO GRADUALLY INCREASE THROUGH THE DAY AS
THE STRONG MOISTURE ADVECTION CONTINUES AND 850-700 MB FGEN
INCREASES. THE GREATEST CHANCE IS EXPECTED OVER THE EAST IN
PROXIMITY TO THE STRONGER DYNAMICS AND BEST MOISTURE. AS THE DRY
LAYER FILLS IN ANY DRIZZLE WILL CHANGE OVER TO RAIN BY MID TO LATE
AFTERNOON. TEMPS WILL CLIMB ABOVE NORMAL INTO THE LOW TO MID 40S.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 426 PM EST SAT NOV 22 2014
QUITE AN ACTIVE START TO THE PERIOD AS THE PHASING OF NORTHERN AND
SOUTHERN ENERGY WILL BE UNDERWAY ACROSS THE UPPER GREAT LAKES.
MODERATE RAINFALL SUNDAY NIGHT WILL GIVE WAY TO A TRANSITION TO SNOW
ON MONDAY AS THE SYSTEM MOVES NE OF THE REGION. THE INGREDIENTS ARE
STILL THERE FOR MODERATE TO POSSIBLY HEAVY SNOW ACROSS AT LEAST THE
WESTERN CWA MONDAY AFTERNOON AND NIGHT. AFTER A REPRIEVE LATE
TUESDAY...A CLIPPER SYSTEM LOOKS TO BRING LIGHT TO POSSIBLY MODERATE
SNOWFALL WEDNESDAY AFTERNOON INTO THANKSGIVING.
SUNDAY NIGHT THROUGH MONDAY NIGHT...FIRST A LOOK AT THE OVERALL
SYNOPTIC PATTERN. TWO POTENT MID-LEVEL SHORTWAVES...ONE TRACKING
EASTWARD OVER THE NORTHERN PLAINS AND THE OTHER MOVING NORTHEASTWARD
NEAR SOUTHERN IL AT 00Z MONDAY WILL BEGIN TO MERGE ACROSS THE UPPER
GREAT LAKES. THE NORTHERN STREAM IS A BIT SLOWER REACHING THE REGION
THAN THE SOUTHERN STREAM...RESULTING IN A BROADENING OF THE TROUGH
BY MONDAY MORNING. MEANWHILE...A DEVELOPING MODEST COUPLED JET
PATTERN WILL DEVELOP OVER THE UPPER GREAT LAKES. THE SOUTHERN WAVE
WILL BE OF MOST INTEREST INITIALLY AS IT INDUCES A RAPIDLY DEEPENING
LOW OVER ILLINOIS AT THE START OF THE PERIOD. WITH THE 12/18Z NAM
RUNS COMING INTO BETTER AGREEMENT WITH THE OTHER MODELS...CONFIDENCE
IS NOW HIGHER REGARDING THE OVERALL EVOLUTION OF THE SYSTEM. THE SFC
LOW IS PROGGED TO TRACK NEAR THE STRAITS OF MACKINAC AROUND 12Z
MONDAY. THE GEM/NAM/ECMWF HINT AT A SLIGHT DEVIATION TO THE LEFT/NW
MONDAY MORNING...WITH THE LOW CROSSING NEAR SAULT STE MARIE. THIS
LOOKS REASONABLE AS THE INFLUENCE OF THE NORTHERN TROUGH APPROACHES.
A LINGERING TROUGH WILL THEN REMAIN ACROSS UPPER MI ON MONDAY AS THE
MID-LEVEL TROUGH AXIS REACHES THE REGION AND THE SFC LOW MOVES TO
JUST SE OF JAMES BAY.
NOW A LOOK AT THE OVERALL PRECIP TYPE AND INTENSITY. MID/UPPER-LEVEL
DYNAMICS AND LOW-LEVEL THERMODYNAMICS SUPPORT MODERATE RAIN ACROSS
MAINLY CENTRAL AND EASTERN UPPER MI SUNDAY NIGHT. THE RIGHT ENTRANCE
OF A DEVELOPING...ALBEIT ANTICYCLONICALLY CURVED...UPPER JET WILL
MAXIMIZE UPPER DIVERGENCE OVER CENTRAL AND EASTERN UPPER MI WHILE
MID-LEVEL Q-VECTOR CONVERGENCE PEAKS OVER NORTHERN LOWER MI.
MEANWHILE...LOW-LEVEL MOISTURE TRANSPORT WILL BE RATHER IMPRESSIVE
ACROSS THE EASTERN CWA...THEN QUICKLY DIMINISH TOWARD THE WESTERN
CWA. A SUFFICIENTLY DEEP LOW-LEVEL WARM LAYER WILL KEEP PRECIP ALL
RAIN ACROSS THE CWA...THOUGH A TRANSITION TO SNOW WILL BE UNDERWAY
LATE SUNDAY NIGHT ACROSS THE WEST AS CAA BEGINS BEHIND THE LOW. ALL
THIS TOGETHER FAVORS MODERATE RAIN ACROSS THE EAST HALF SUNDAY
NIGHT...WITH AN INITIALLY SHARP CUTOFF TO THE WEST BEFORE THE
NORTHERN WAVE APPROACHES OVERNIGHT.
CAA TAKING HOLD ON MONDAY WILL QUICKLY TRANSITION THE RAIN TO SNOW
FROM WEST TO EAST THROUGHOUT THE DAY. THERE ARE SOME INDICATIONS
THAT A LOW-LEVEL WARM LAYER MAY TRY TO WRAP AROUND THE BACK SIDE OF
THE LOW LATE MORNING MORNING INTO THE AFTERNOON. SOME SLEET MAY MIX
IN WITH THE RAIN/SNOW...BUT THE TRANSITION FROM ALL RAIN SNOW SHOULD
NOT TAKE MORE THAN AN HOUR OR TWO. THINK THAT EVEN THE SHORELINE
LOCATIONS SHOULD TRANSITION QUICKLY GIVEN THEN COLDER THAN AVERAGE
LAKE TEMPS. TRANSITION TIMES LOOK TO BE AROUND 09Z FOR IWD...12Z FOR
A LINE FROM HOUGHTON TO IRON RIVER...AND 15Z FOR A LINE FROM
MARQUETTE TO IMT. BY 21Z...ALL BUT POSSIBLY LUCE COUNTY SHOULD
TRANSITION TO SNOW.
A FAIRLY IMPRESSIVE MID-LEVEL FGEN/DEFORMATION ZONE WILL SET UP OVER
THE WESTERN CWA BY MONDAY AFTERNOON. WITH SOME SNOWFLAKE FRACTURING
FROM THE HIGHER WINDS AND THE MAX LIFT INITIALLY OCCURRING AT TEMPS
JUST A BIT WARMER THAN THE DGZ...SNOW RATIOS MAY REMAIN LOW /10 TO
1/ THROUGH MONDAY MORNING. AS TEMPS CONTINUE TO FALL IN TO THE
AFTERNOON SNOW RATIOS WILL BE ON THE RISE ACROSS THE WEST. LOW-LEVEL
WINDS AVERAGING OUT THE NORTH COMBINED WITH LAKE-850MB DELTA TEMPS
SURPASSING 10C SUPPORT DECENT LAKE-ENHANCEMENT FOR THE NORTH WIND
SNOW BELTS THROUGHOUT MONDAY. THIS PATTERN WILL CONTINUE INTO MONDAY
EVENING AS THE CONSOLIDATED TROUGH SLOWS OVER THE AREA AND KEEPS A
SFC TROUGH EXTENDED ACROSS MUCH OF EASTERN UPPER MI. ON TOP OF THE
SNOW...THE CAA WITH A STRONG WNW TO ESE ISALLOBARIC COMPONENT FROM
THE RAPIDLY DEEPENING LOW WILL YIELD A QUICK INCREASE IN WIND FROM
THE N/NNW.
WHEN ALL IS SAID AND DONE...SNOWFALL MONDAY AND MONDAY NIGHT IS
EXPECTED TO BE 6 TO 10 INCHES BASICALLY NORTH OF M-28 AND WEST OF
MARQUETTE. ELSEWHERE ACROSS THE CWA...2-4 INCHES IS EXPECTED.
HOWEVER...HIGHER AMOUNTS OF UP TO 6 INCHES WILL BE POSSIBLE FOR THE
NNW WIND SNOW BELTS FROM SHOT POINT TO GRAND MARAIS. THREW AROUND
THE IDEA OF A WINTER STORM WATCH FOR THE NW HALF...BUT DECIDED
AGAINST IT GIVEN SOME DETAILS IN QPF AND PLACEMENT OF FORCING THAT
NEED TO BE IRONED OUT. HOWEVER...WINTER WX ADVISORY CRITERIA SHOULD
BE MET. HAVE OPTED TO ISSUE A SPECIAL WX STATEMENT AT THIS TIME TO
HIGHLIGHT THE POTENTIAL...BUT ALSO NOTE THE UNCERTAINTY IN AMOUNTS.
MAIN IMPACTS WILL BE RATHER SLUSHY ROADS IN THE AFTERNOON FOLLOWED
BY BLOWING AND DRIFTING OF THE SNOW OVERNIGHT AS SNOW RATIOS
INCREASE.
TUESDAY THROUGH WEDNESDAY NIGHT...WEAK MID-LEVEL RIDGING...LOW-LEVEL
WAA AND INVERSION HEIGHTS FALLING BELOW 3KFT WILL PUT A QUICK END TO
THE LES FROM WEST TO EAST THROUGHOUT THE DAY. A CLIPPER SHORTWAVE
WILL TRACK SE INTO THE UPPER MS VALLEY LATE TUESDAY. THE SHORTWAVE
LOOKS TO GET CAUGHT UP IN A LARGER-SCALE TROUGH OVER HUDSON
BAY...ULTIMATELY SLOWING ITS PROGRESSING AND SHIFTING IT TO A ENE
TRACK. WHERE THIS TAKES PLACE WILL BE CRUCIAL FOR DETERMINING SNOW
PROBABILITY/AMOUNTS FOR THE CWA. THE GFS IS THE FASTEST...BRINGING
WIDESPREAD ACCUMULATING SNOW TO THE AREA LATE TUESDAY NIGHT INTO
WEDNESDAY AFTERNOON. THE ECMWF TAKES AN INITIALLY MORE AGGRESSIVE
EVOLUTION...RESULTING THE THE TROUGH DIGGING FARTHER SOUTHEAST
BEFORE PIVOTING ACROSS SOUTHERN LAKE/LOWER MI. WITH THIS
SCENARIO...MOST OF THE SNOW HOLDS OFF UNTIL WEDNESDAY NIGHT. THE GEM
FOLLOWS A SOLUTION IN THE MIDDLE...BUT LEANS MORE IN LINE WITH THE
GFS. ATTM...CANNOT REALLY PIN DOWN AMOUNTS AND EXACT TIMING...THOUGH
THE PROSPECTS FOR SEVERAL INCHES OF ACCUMULATING SNOW SOMETIME LATE
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT ARE GROWING.
THANKSGIVING...DEPENDING ON WHAT MODEL SOLUTION PANS
OUT...WIDESPREAD SNOW MAY LINGER THROUGH THE MORNING OR END BEFORE
DAYBREAK. EITHER WAY...CAA BEHIND THE CLIPPER SHOULD YIELD LES FOR
THE N/NNW WIND BELTS DURING THE DAY. IT STILL LOOKS COLD...WITH
TEMPS MORE IN LINE WITH CHRISTMAS RATHER THAN THANKSGIVING.
HOWEVER...WITH THE SLOWER SOLUTION...THE ECMWF HAS A HARDER TIME
BRINGING THE COLDEST AIR INTO THE REGION.
FRIDAY AND SATURDAY...LONG RANGE MODELS HAVE BACKED OFF SOMEWHERE ON
A TRANSITION TO A MORE ZONAL AND MILD PATTERN BEGINNING FRIDAY AND
DELAY IT UNTIL LATE IN THE WEEKEND. THE OVERALL PATTERN LOOKS QUIET
BESIDE SOME LES FOR THE WNW WIND SNOW BELTS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1244 PM EST SAT NOV 22 2014
LOW CLOUDS ARE THE MAIN FORECAST ISSUE INTO SUNDAY. ALTHOUGH THERE
WERE SOME BREAKS IN THE OVERECAST IN DOWNSLOPE AREAS IN CNTRL UPPER
MI EXPECT MVFR CIGS TO PERSIST AT THE TAF SITES THIS AFTERNOON.
CONTINUING MOISTURE FLOWING INTO THE AREA SHOULD RESULT IN LOWERING
OF CIGS TONIGHT. BASED ON UPSTREAM CIGS THIS MORNING OVER
IA/MN/WI...EXPECT CIGS TO FALL TO IFR LATE TONIGHT...OR EVEN
LIFR...AS THE MOIST LOW-LEVELS WILL BE ONLY BE ADDED TO BY
ADDITIONAL MOISTURE AND HELPED ALONG BY DEVELOPING UPSLOPE FLOW AT
KCMX AND KSAW. AT THESE SITES....PROBABLY WILL SEE DRIZZLE AND FOG
AS WELL WITH VSBY LIKELY REACHING IFR LATE TONIGHT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 420 PM EST SAT NOV 22 2014
SOUTH WINDS WILL INCREASE ON SUNDAY...ESPECIALLY OVER EASTERN
SECTIONS...BUT SHOULD REMAIN 30 KTS OR LESS. WINDS WILL BE VARIABLE
SUNDAY NIGHT AS TROUGH CROSSES LAKE SUPERIOR. A DEEPENING LOW WILL MOVE
TO EAST OF LAKE SUPERIOR ON MONDAY. NORTHERLY WINDS WILL INCREASE TO
GALES 40-45 KTS MONDAY AFTN INTO MONDAY NIGHT. WINDS DIMINISH TO 25
KTS OR LESS LATER TUESDAY INTO WEDNESDAY...THEN INCREASE TO 30 KTS
ON THURSDAY AS COLD AIR POURS ACROSS LAKE SUPERIOR BETWEEN HIGH PRESSURE
BUILDING OVER THE NORTHERN PLAINS AND LOW PRESSURE CROSSING THE
LOWER GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM MONDAY AFTERNOON THROUGH LATE MONDAY NIGHT FOR
LSZ248>250-265-266.
GALE WATCH FROM MONDAY MORNING THROUGH LATE MONDAY NIGHT FOR
LSZ242>245-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KLUBER
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
421 PM EST SAT NOV 22 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 420 PM EST SAT NOV 22 2014
WV IMAGERY AND RUC ANALYSIS INDICATED ZONAL FLOW ACROSS THE NRN
CONUS WITH A STRONG 170 KNOT 250 MB JET MOVING INTO THE PAC NW. A
SHORTWAVE TROUGH WAS MOVING THROUGH SRN SASK AND NRN MT. A VIGOROUS
SRN SHORTWAVE TROUGH WAS LOCATED OVER WRN TEXAS. AT THE SFC...SRLY
FLOW PREVAILED FROM THE GULF TOWARD THE UPPER MS VALLEY AND NRN
LAKES BTWN HIGH PRES OVER THE MID ATLANTIC AND A 984 MB LOW INTO SRN
SASK. WAA HAS PUSHED TEMPS INTO THE MID AND UPPER 30S ACROSS UPPER
MI. ALTHOUGH THE LOW LEVEL MOISTURE THINNED OUT ENOUGH FOR SOME
SUNSHINE THIS AFTERNOON...ESPECIALLY IN DOWNSLOPE LOCATIONS...CLOUDS
OVER NRN WI AND WRN UPPER MI WERE FILLING IN AGAIN ACROSS THE AREA.
TONIGHT...ANY LINGERING DRY LOW LEVEL AIR WILL FILL IN TONIGHT WITH
STRONG LOW LEVEL MOISTURE ADVECTION THIS EVENING. SO...EXPECT BETTER
CHANCES FOR PCPN AS DRIZZLE OR POSSIBLY FREEZING DRIZZLE AS A
SUBSTANTIAL DRY LAYER REMAINS ABOVE 900 MB. SOME FOG WILL BE POSSIBLE
AS WELL AS DEWPOINTS CLIMB TO AROUND FREEZING OR SLIGHTLY ABOVE BY
LATE TONIGHT. EXPECT THE BEST CHANCE FOR DRIZZLE OVER CNTRL UPPER MI
WITH AN UPSLOPE LOW LEVEL WIND COMPONENT SUPPORT...AND OVER THE EAST
CWA WITH ADDED MOISTURE OFF OF LAKE MICHIGAN. TEMPS MAY DROP OFF TO
NEAR FREEZING THIS EVENING AND SLOWLY CLIMB OVERNIGHT.
HOWEVER...SINCE MANY ROAD SURFACES MAY STILL BE BELOW FREEZING...ANY
DRIZZLE THAT FALLS COULD CREATE ICY/SLIPPERY CONDITIONS ON UNTREATED
ROADS.
SUN...EXPECT PCPN CHANCES TO GRADUALLY INCREASE THROUGH THE DAY AS
THE STRONG MOISTURE ADVECTION CONTINUES AND 850-700 MB FGEN
INCREASES. THE GREATEST CHANCE IS EXPECTED OVER THE EAST IN
PROXIMITY TO THE STRONGER DYNAMICS AND BEST MOISTURE. AS THE DRY
LAYER FILLS IN ANY DRIZZLE WILL CHANGE OVER TO RAIN BY MID TO LATE
AFTERNOON. TEMPS WILL CLIMB ABOVE NORMAL INTO THE LOW TO MID 40S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 559 AM EST SAT NOV 22 2014
A VERY ACTIVE WEEK IS IN STORE ACROSS THE UPPER GREAT LAKES AS A
POTENT PACIFIC SHORTWAVE DIGS SE AND CARVES OUT A MID-LVL TROUGH
OVER THE PLAINS. THIS WILL BRING A DECENT SURGE OF WARM AIR ACROSS
THE AREA THIS WEEKEND...RESULTING IN ABOVE-AVERAGE TEMPERATURES FOR
A SHORT PERIOD. FORCING AHEAD OF THE ASSOCIATED SFC LOW PRESSURE
SYSTEM WILL ALSO BRING A BATCH OF MODERATE RAIN ACROSS MAINLY
CENTRAL AND EASTERN UPPER MI SUNDAY NIGHT INTO MONDAY. A QUICK
TRANSITION BACK TO WINTER WILL THEN TAKE PLACE ON MONDAY INTO MONDAY
NIGHT AS THE TROUGH AND ASSOCIATED STRONG SURFACE LOW MOVE NORTHEAST
OF THE REGION...BRINGING STRONG CAA AND THE POTENTIAL FOR A MODERATE
TO HEAVY SNOWFALL ACROSS THE WESTERN CWA.
SUN INTO SUNDAY NIGHT...MODELS CONTINUE TO INDICATE LOW PRES RAPIDLY
DEVELOPING OVER THE SRN PLAINS LATE TONIGHT AND SUN IN RESPONSE TO
THE STRONG PACIFIC SHORTWAVE DIGGING INTO THE BASE OF THE SRN STREAM
TROUGH. MEANWHILE...ADDITIONAL ENERGY MOVING OUT OVER THE NRN PLAINS
WILL HELP PULL THIS SYSTEM NORTH AND WITH THE SUBSEQUENT PHASING THE
SFC LOW IS EXPECTED TO RAPIDLY DEEPEN BASICALLY BOMBING OUT INTO THE
970S MB BY THE TIME IT REACHES THE UPPER LAKES MON MORNING. THE
GFS/GEM-NH AND ECMWF ARE NOW ALL IN FAIRLY AGREEMENT SHOWING A SFC
LOW TRACK TOWARD THE MACKINAC STRAITS BY MON MORNING. THE 00Z RUNS
OF THE GEM-NH AND GFS SHOW A DEEPER LOW (IN THE LOW 970S) WHILE THE
ECMWF SHOWS A LOW PRES CENTER IN HIGH 970S. ALL MODELS SUGGEST THAT
PCPN ON THE FRONT SIDE OF THIS SYSTEM WILL BE ALL RAIN FOR UPPER MI
SUNDAY AFTERNOON INTO SUNDAY NIGHT. PCPN WILL LIKELY BE MORE IN THE
FORM OF DRIZZLE SUN MORNING AS SFC-BASED MOIST LAYER STAYS ABOVE
FREEZING WITH DRY AIR ALOFT IN THE DGZ REGION. MODELS FAIRLY
CONSISTENT SHOWING BEST SURGE OF RAIN INTO UPPER MI LATE SUNDAY INTO
SUN NIGHT. COUPLED UPPER JET STRUCTURE SUPPORTING THE RAPID
DEEPENING OF THE SFC LOW AND DEEP LAYER Q-VECT CONVERGENCE WILL
SUPPORT WIDESPREAD RAIN ACROSS THE CWA ON SUNDAY NIGHT. LOOK FOR THE
GREATEST PCPN...PERHAPS MORE THAN ONE INCH...TO OCCUR OVER THE ERN
COUNTIES WHERE THE BEST 850-700 MB MOISTURE TRANSPORT IS EXPECTED
CLOSER TO THE TRACK OF THE SFC LOW.
MON INTO MON NIGHT...AS THE SYSTEM LIFTS NNE AND THE COLUMN COOLS
UNDER FALLING HEIGHTS...MODELS INDICATE DEFORMATION/COMMA HEAD PCPN
SHIELD DEVELOPING. THE FCST CHALLENGE WILL BE DETERMINING THE
STRENGTH AND PERSISTENCE OF THIS DEFORMATION PCPN SHIELD AND WHERE
IT WILL SET UP. 00Z MODELS NOW HINTING THAT BEST DEFORMATION/MOST
PERSISTENT 700 MB FGEN FORCING WILL BE OVER THE WRN COUNTIES WHERE
PCPN WILL BE CHANGING OVER TO SNOW MON MORNING. WITH 850MB TEMPS
COOLING TO AROUND -12C LATE MON...LAKE ENHANCEMENT WILL ALSO COME
INTO PLAY. STILL HAVE THE WRN CWA PEGGED FOR THE POTENTIAL OF
MODERATE TO POTENTIALLY HEAVY SNOW MON INTO MON NIGHT ALONG WITH
BLUSTERY NW WINDS DEVELOPING BEHIND THE SYSTEM AND WILL CONTINUE TO
HIGHLIGHT IN HWO AND EHWO GRIDS. WITH MODEL AVERAGED QPF OF .5-.7
AND SNOW/WATER RATIOS NEAR 10/1 MON MORNING RAISING TO 20/1 LATE MON
NIGHT...HAVE COME UP WITH 24 HR SNOW TOTALS OF 7-9 INCHES OVER SOME
HIGHER TERRAIN LOCATIONS OF WEST FROM KIWD UP TO KCMX. THE SNOW/WIND
WILL SPREAD INTO THE ERN FCST AREA AS WELL...BUT WITH DEFORMATION
PCPN TENDING TO LIFT NE...SNOWFALL WILL LIKELY BE LIGHTER THAN OVER
THE W.
WITH 850MB TEMPS FM -12C TO -14C TUE...NW FLOW LAKE ENHANCEMENT WILL
TRANSITION TO PURE LES AS TROF SHIFTS E AND DEEP MOISTURE DEPARTS.
WITH A TREND TOWARD MORE ANTICYCLONIC FLOW...THERE WILL BE A
DIMINISHING OF NW FLOW LES THRU THE DAY NEAR THE LAKE...BUT WILL
MAINTAIN LIKELY TO CATEGORICAL POPS AT LEAST FOR THE MORNING OVER
THESE AREAS.
HEADING INTO WED/THU...AFTER A BRIEF BREAK FROM THE SNOW TUE NIGHT
...IT LOOKS LIKE THERE MAY BE A POTENTIAL FOR SOME MORE SNOW WED
INTO THANKSGIVING AS MEDIUM RANGE MODELS SHOW INDICATIONS OF A
CLIPPER SHORTWAVE DIVING THROUGH THE MIDWEST/GREAT LAKES REGION.
GFS IS QUITE A BIT QUICKER THAN THE ECMWF/GEM-NH/UKMET WITH THIS
WAVE AND SEEMS TO BE AN OUTLIER AT THIS POINT. THE ECMWF SOLN SHOWS
A BIT DEEPER SYSTEM AND MORE PROLONGED TROFFING INTO THE UPPER GREAT
LAKES WHICH WOULD LIKELY YIELD MORE SNOW. WILL HIGHLIGHT IN EHWO
GRIDS AT LEAST A LIMITED POTENTIAL FOR MODERATE SNOW ALONG THE LAKE
SUPERIOR COUNTIES.
BOTH THE ECMWF AND GEM-NH SHOW RIDGING WORKING IN FROM THE WEST BY
NEXT FRIDAY WHICH SHOULD ALLOW FOR A DIMINISHING TREND TO LES FOR NW
FLOW AREAS ALONG LAKE SUPERIOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1244 PM EST SAT NOV 22 2014
LOW CLOUDS ARE THE MAIN FORECAST ISSUE INTO SUNDAY. ALTHOUGH THERE
WERE SOME BREAKS IN THE OVERECAST IN DOWNSLOPE AREAS IN CNTRL UPPER
MI EXPECT MVFR CIGS TO PERSIST AT THE TAF SITES THIS AFTERNOON.
CONTINUING MOISTURE FLOWING INTO THE AREA SHOULD RESULT IN LOWERING
OF CIGS TONIGHT. BASED ON UPSTREAM CIGS THIS MORNING OVER
IA/MN/WI...EXPECT CIGS TO FALL TO IFR LATE TONIGHT...OR EVEN
LIFR...AS THE MOIST LOW-LEVELS WILL BE ONLY BE ADDED TO BY
ADDITIONAL MOISTURE AND HELPED ALONG BY DEVELOPING UPSLOPE FLOW AT
KCMX AND KSAW. AT THESE SITES....PROBABLY WILL SEE DRIZZLE AND FOG
AS WELL WITH VSBY LIKELY REACHING IFR LATE TONIGHT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 420 PM EST SAT NOV 22 2014
SOUTH WINDS WILL INCREASE ON SUNDAY...ESPECIALLY OVER EASTERN
SECTIONS...BUT SHOULD REMAIN 30 KTS OR LESS. WINDS WILL BE VARIABLE
SUNDAY NIGHT AS TROUGH CROSSES LAKE SUPERIOR. A DEEPENING LOW WILL MOVE
TO EAST OF LAKE SUPERIOR ON MONDAY. NORTHERLY WINDS WILL INCREASE TO
GALES 40-45 KTS MONDAY AFTN INTO MONDAY NIGHT. WINDS DIMINISH TO 25
KTS OR LESS LATER TUESDAY INTO WEDNESDAY...THEN INCREASE TO 30 KTS
ON THURSDAY AS COLD AIR POURS ACROSS LAKE SUPERIOR BETWEEN HIGH PRESSURE
BUILDING OVER THE NORTHERN PLAINS AND LOW PRESSURE CROSSING THE
LOWER GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM MONDAY AFTERNOON THROUGH LATE MONDAY NIGHT FOR
LSZ248>250-265-266.
GALE WATCH FROM MONDAY MORNING THROUGH LATE MONDAY NIGHT FOR
LSZ242>245-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...VOSS
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
353 PM CST SAT NOV 22 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 238 PM CST SAT NOV 22 2014
MAIN CONCERN DURING THE SHORT TERM PERIOD IS THE TREND OF STRATUS
AND THE POTENTIAL EXTENT OF FOG TONIGHT. A SECONDARY CONCERN IS WITH
PRECIP POTENTIAL TONIGHT INTO SUNDAY...THOUGH MODELS CONTINUE TO
SHOW PRECIP AMOUNTS BEING PRETTY UNDERWHELMING THROUGH SUNDAY ACROSS
THE ENTIRE MPX AREA...WITH DEEPER MOISTURE GOING ACROSS ERN WI AND
MICHIGAN.
EXTENSIVE STRATUS ACROSS ALL BUT THE NW PORTION OF THE MPX CWA HAS
HELD TEMPERATURES IN CHECK ALL DAY. LOOKING TO THE SOUTH...THERE ARE
A COUPLE OF MOISTURE SURGES HEADING OUR WAY. THE FIRST IS QUICKLY
MOVING INTO NRN IA AND WILL LIKELY BE TO THE I-90 CORRIDOR BY 00Z
THIS EVENING. IT IS CHARACTERIZED BY DEWPS IN THE 40S AND MORE
CONCERNING FOR THE CLOUD FORECAST TONIGHT...CLEAR SKIES. THE SECOND
MOISTURE SURGE IS JUST NOW GETTING TO I-80 AND IT IS ASSOCIATED WITH
DEWPS IN THE 50S...AND A RETURN TO LIFR STRATUS AND FOG. THE
ECMWF/GEM SHOW THIS SECOND MOISTURE SURGE AND ITS ASSOCIATED LOWER
50 DEWPS GETTING CLEAR UP TO I-90 SUNDAY MORNING BEFORE GETTING
SHUNTED OFF TO THE EAST. CERTAINLY DEWPS IN THE 40S WITH SNOW ON THE
GROUND FAVORS STRATUS CONTINUING THROUGH THE NIGHT AND THE CURRENT
FORECAST CERTAINLY READS THAT WAY...BUT WE WILL HAVE WATCH HOW THAT
CLEARING EVOLVES.
FOR FOG...ONE THING WE ARE POSITIVE ABOUT IS IT WILL BE HAZY TROUGH
THE NIGHT GIVEN DEWPS ABOVE FREEZING WITH SNOW ON THE GROUND. THERE
WAS TALK OF A DENSE FOG ADVISORY...BUT NOT CONFIDENT ENOUGH ON WHERE
TO PUT ONE OTHER THAN ANYONE UNDER STRATUS NOW...WHICH IS JUST ABOUT
OUR ENTIRE CWA AND DID NOT WANT TO ISSUE SUCH A LARGE ADVY AT THIS
POINT. ON TOP OF THAT...WE WILL BE MAINTAINING 8-12 KT WINDS THROUGH
THE NIGHT...SO THAT WILL SUPPLY A CERTAIN DEGREE OF MIXING AS WELL.
NOT TO MENTION WE HAVE THAT CLEARING RACING NORTH OUT OF IA. AT THIS
POINT...HIGHEST CONFIDENCE IN DENSE FOG IS WHERE OUR DEEPEST SNOW
RESIDES ACROSS THE NRN MPX CWA. THE HRRR WOULD SUPPORT THIS IDEA AS
IT DOES SHOW VSBYS IMPROVING THROUGH THE NIGHT ACROSS SRN MN AS THAT
SLUG OF SLIGHTLY DRIER AIR ACROSS IA WORKS INTO MN.
FOR TEMPERATURES...THEY MAY GO NOTHING BUT UP THROUGH THE NIGHT.
FIRST RUN OF THE HOURLY TEMPERATURE TOOL WITH THE LOCAL SUPERBLEND
BROUGHT A TEMPERATURE OF 53 TO ALBERT LEA BY 7Z TONIGHT. DID NOT GO
QUITE THAT AGGRESSIVE...BUT DO THINK MUCH OF THE AREA EAST OF A NEW
ULM TO MORA LINE WILL RISE INTO THE 40S OVERNIGHT. GIVEN THE MILD
START...ALSO GAVE HIGHS SUNDAY A BIT OF AN UPWARD NUDGE TO ABOUT A
50/50 BLEND BETWEEN THE PREVIOUS FORECAST AND THE 22.12 GEM/ECMWF.
THE GEM/ECMWF SHOW HIGHS IN THE LOW 50S FOR SE MN/WRN WI TOMORROW.
GIVEN THE EXTENSIVE CLOUD COVER...DO NOT THINK WE WILL GET THAT
HIGH...BUT DO HAVE HIGHS INTO THE MID/UPPER 40S FOR ALL BUT WRN AND
CENTRAL MN.
FOR PRECIP...THAT CONTINUES TO LOOK UNDERWHELMING. OUR BIGGEST
PROBLEM THROUGH TONIGHT CONTINUES TO BE THE FACT THAT THE ATMO CAN
NOT TAKE ON MUCH MORE MOISTURE BELOW 900 MB...BUT ABOVE THAT...ITS
BONE DRY. CONTINUED TO RUN WITH HIGHEST POPS SUNDAY OUT IN ERN AREAS
AS THEY WILL BE CLOSER TO THE H85 MOISTURE TRANSPORT...BUT LIKING
THE IDEA THE GFS/SREF/NMM/ARW SHOW OF A NARROW BAND OF RAIN CENTERED
ON FGEN IN THE H7-H6 LAYER COMING OUT OF SODAK TONIGHT AND WORKING
ACROSS SRN MN THROUGH SUNDAY MORNING. THE 22.18 HOPWRF MEMBERS ALSO
SHOW THIS BAND OF PRECIP BY 9Z /THE END OF THOSE RUNS/ MOVING INTO
THE WRN PORTION OF THE FSD FORECAST AREA...SIMILAR TO WHAT THE
MODELS MENTIONED ABOVE SHOW. DID BOOST POPS IN SW MN INTO THE HIGH
CHANCE CATEGORY SUNDAY MORNING FOR NOW. THIS MAY VERY WILL END UP
BEING THE BEST CHANCE AT SEEING MEASURABLE PRECIP WITH THIS SYSTEM
FOR MUCH OF OUR MN FORECAST AREA.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 238 PM CST SAT NOV 22 2014
SUNDAY NIGHT THROUGH MONDAY WILL BRING A PERIOD OF STRONG WINDS
AND LIGHT PRECIPITATION TO THE FORECAST AREA...IN THE WAKE OF A
DEEPENING MID LATITUDE CYCLONE. THE STRONGEST WINDS ARE EXPECTED
ACROSS THE WESTERN FORECAST AREA AND THE HIGHEST POTENTIAL FOR
ACCUMULATING SNOW REMAINS ACROSS FAR EASTERN MN...BUT ESPECIALLY
IN WEST CENTRAL WI.
BY 00Z MONDAY...RAPID CYCLOGENESIS WILL BE ONGOING IN THE MID
MISSISSIPPI RIVER VALLEY IN RESPONSE TO A DEEP TROUGH DIGGING IN
ACROSS THE CENTRAL CONUS AND A LARGE AREA OF 120-150M 500MB 12-HR
HEIGHTS FALLS MOVING ACROSS THE AREA. THE AMOUNT OF DEEPENING IS
STILL QUITE VARIABLE DEPENDING ON WHICH 12Z SOLUTION ONE CHOOSES TO
FOLLOW. THE 22.12Z GFS IS BY FAR AND AWAY THE MOST AGGRESSIVE IN
STRENGTHENING THE LOW OVER THE SOUTHERN HALF OF LAKE MICHIGAN BY
06Z MONDAY TO 975MB...969MB OVER NORTHERN MICHIGAN BY 12Z...AND
966MB AS IT MOVES NORTH OF THE GREAT LAKES BY 18Z. THE NAM AND
ECMWF SEEM MORE REASONABLE WITH A BIT MORE MODEST DEEPENING.
TYPICALLY...THE KIND OF DEEPENING THE GFS IS SHOWING ONLY OCCURS
WITH VERY STRONG BAROCLINICITY AND/OR A NEGATIVELY TILTED UPPER
TROUGH. WE REALLY DON`T HAVE EITHER. THERE IS STRONG COLD
ADVECTION AND A DECENT TEMPERATURE GRADIENT ACROSS THE MID/UPPER
MISSISSIPPI VALLEY...BUT THEY SEEM MORE IN LINE WITH THE NAM/ECMWF
THAT ARE BIT MORE PROGRESSIVE WITH THE LOW AND NOT AS WOUND UP.
THEREFORE...WE DID NOT JUMP ON THE GFS SNOWFALL FORECAST THAT
WOULD GIVE 6-8" TO PORTIONS OF WEST CENTRAL WI. WE THINK THE
HEAVIEST PRECIP SHOULD BE EAST OF THE FORECAST AREA AND THE
DYNAMIC COOLING ON THE BACK SIDE OF THE LOW WILL BE WEAKER THAN
THE GFS INDICATES. IT IS NOTABLE THAT THE 22.15Z SREF AND GEM ALSO
SHOW THE POTENTIAL FOR SEVERAL INCHES OF SNOW NEAR OR JUST EAST OF
THE FORECAST AREA. THIS IS SOMETHING TO FOLLOW OVER THE NEXT 12-18
HOURS...BUT WE SIMPLY DIDN`T HAVE ENOUGH CONFIDENCE TO ISSUE A
WINTER STORM WATCH AT THIS POINT. FURTHERMORE...EVEN WITH THE
EXPECTED STRONG WINDS...THE WARM TODAY HAS LIKELY LIMITED THE
AMOUNT OF SNOW AVAILABLE FOR BLOWING AND DRIFTING. THERE WERE A
LOT OF HIGHS IN THE UPPER 30S AND LOWER 40S IN WESTERN MN TODAY.
THE NEXT SYSTEM TO WATCH ARRIVES ON WEDNESDAY AND THERE IS AGAIN
SIGNIFICANT DIFFERENCES BETWEEN THE GFS AND ECMWF. THE ECMWF HAS A
POTENT CLIPPER SYSTEM WITH 1-4" OF SNOW...IMPRESSIVE COLD
ADVECTION AND A TIGHT PRESSURE GRADIENT ON THE BACK SIDE OF THE
SYSTEM. THE 22.12Z ECMWF HAS SUSTAINED 25-30KTS NEAR THE ND/SD/MN
BORDER EARLY WEDNESDAY MORNING - QUITE IMPRESSIVE GIVEN ITS
COARSER RESOLUTION. THE GFS HAS A WEAK SURFACE TROUGH AND MUCH
LESS LIFT. THIS MID WEEK SYSTEM PRETTY MUCH LOCKS IN OUR CHANCE
FOR A WELL BELOW NORMAL THANKSGIVING. IT LOOKS VERY COLD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1148 AM CST SAT NOV 22 2014
IFR AND LOWER STRATUS CONTINUES TO SLOWLY CRAWL NW ACROSS
MN...STILL QUESTIONABLE WHETHER OR NOT IT REACHES AXN...BUT WITH
12Z TAF HAVING IT GETTING THERE...KEPT THAT TREND GOING. THESE
CIGS WILL ONLY MARGINALLY IMPROVE THROUGH THE AFTERNOON...LIKELY
JUST GOING FROM LIFR TO IFR BEFORE GOING BACK TO LIFR TONIGHT.
GIVEN CONTINUED SOUTH WINDS AND INCREASING MOISTURE OVER THE SNOW
THROUGH THE NIGHT...KEPT THE TREND FOR FG TONIGHT FROM 12Z TAFS
GOING. UNCERTAINTY STARTS TO INCREASE TOMORROW WITH THE POTENTIAL
FOR CIGS TO QUICKLY GO VFR. FOR NOW...TIMED IMPROVEMENT IN CIGS TO
WHEN WINDS ARE FORECAST TO SWING AROUND TO 240 DEGS OR GREATER.
SREF MVFR CIG PROBABILITY DROPS TO NEAR ZERO SUNDAY MORNING OUT
WEST...SO WE COULD VERY WELL SEE CIGS IMPROVE FASTER THAN
CURRENTLY INDICATED ACROSS MN. FOR PRECIP...LOOKING LIKE OUR BEST
CHANCE THIS TAF PERIOD WILL BE WITH A NARROW BAND OF RAIN THE
NMM/ARW/GFS/SREF SHOW COMING OUT OF SODAK LATE TONIGHT AND WORKING
ACROSS MN DURING THE MORNING.
KMSP...CONFIDENCE IS HIGH IN MINIMAL IMPROVEMENTS TO CIGS/VIS
THROUGH THE DAY. CONTINUED MOIST SRLY FLOW WILL ALSO LEAD TO A
LOWERING IN CONDITIONS TONIGHT...THOUGH THERE IS LESS CONFIDENCE
IN THE TIMING ON WHEN CIGS DROP BACK BELOW 005. 50/50 CONFIDENCE
ON THE FOG TEMPO GROUP...BUT WITH IT ALREADY IN THE TAF...LEFT IT
THERE. CONFIDENCE IS CONSIDERABLY LOWER THIS FAR OUT WITH
IMPROVEMENTS IN THE TAF BY SUNDAY AFTERNOON...BUT FOLLOWED THE
IDEA OF THE NAM/SREF ON THAT FOR NOW.
/OUTLOOK FOR KMSP/
MON...MVFR/IFR CIGS CHC -SN. WINDS NW 20G30 KT.
TUE...VFR. WINDS W 5-10 KT.
WED...MVFR/IFR CHC -SN. WINDS NW 10KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...CLF
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1245 PM CST SAT NOV 22 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 440 AM CST SAT NOV 22 2014
WARM AIR ADVECTION REGIME IS THE MAIN STORY OF THE SHORT TERM
PERIOD. BRISK SOUTHERLY WINDS HAVE ALLOWED TEMPERATURES TO CLIMB
ABOVE FREEZING /FOR THE FIRST TIME IN NEARLY TWO WEEKS/ OVERNIGHT
ACROSS SOUTHERN MN AND WESTERN WI. SURFACE DEW POINTS IN THE LOW
TO MID 30S CONTINUE TO PUSH NORTHWARD THROUGH IOWA AND WILL
CONTINUE FILLING IN ACROSS EASTERN MN AND WESTERN WI. WENT WITH A
PESSIMISTIC CLOUD/FOG FORECAST COMPARED TO MUCH OF THE GUIDANCE
WITH THE RELATIVE WARM AND MOIST AIR STREAMING NORTHWARD OVER THE
CURRENT SNOW PACK. DEW POINTS ACROSS WESTERN MN WILL LIKELY REMAIN
BELOW FREEZING THROUGH THE DAY AS THE BEST MOISTURE ADVECTION
STREAMING NORTHWARD TAKES AN EASTWARD TURN. MUCH OF SOUTHEASTERN
MN AND WESTERN WI ARE CURRENTLY SOCKED IN WITH LOW STRATUS AND
FOG...BUT MOSTLY CLEAR SKIES CAN BE FOUND TO THE WEST. THE HRRR
HAS PERFORMED WELL WITH THE COVERAGE OF THE CLOUDS/FOG...SO
WEIGHTED HEAVILY WITH THE HRRR IN THE SHORT RANGE FORECAST. THE
STRATUS DECK IS EXPECTED TO EXPAND SOME TO THE WEST THROUGH THE
MORNING...AND KEEP EASTERN MN AND WESTERN WI SOCKED IN THROUGH THE
DAY.
A COMPLICATED EVOLUTION OF THE FORECAST FOR TONIGHT THROUGH EARLY
SUNDAY MORNING. A NORTHERN STREAM SHORTWAVE WILL MOVE ACROSS
SOUTHERN CANADA TODAY AND MAKE IT TO MANITOBA TONIGHT.
MEANWHILE...THE SOUTHERN STREAM WAVE WILL BE PIVOTING OVER THE
SOUTHERN CONUS. THE BEST AREA OF LIFT WILL LARGELY REMAIN SOUTH OF
OUR AREA TONIGHT...BUT SOME MARGINAL LIFT ARRIVES TONIGHT AND WITH
SATURATED LOW LEVELS...DRIZZLE/LIGHT RAIN WILL BE POSSIBLE ACROSS
EASTERN MN AND WESTERN WI. WITH MODEL SOUNDINGS ALSO INDICATING A
VERY SATURATED NEAR SURFACE ENVIRONMENT...EXPANDED MENTION OF FOG IN
THE FORECAST...ESPECIALLY FOR WESTERN WI.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 440 AM CST SAT NOV 22 2014
A MILD START TO THE LONG TERM PERIOD PRIOR TO THE MERGING OF
NORTHERN AND SOUTHERN STREAM WAVES...AND THEN ANOTHER SURGE OF
ARCTIC AIR BLASTS THE REGION.
00Z MODEL SOLUTIONS WERE FAIRLY SIMILAR IN THEIR DEPICTION OF POPS
FOR SUNDAY...WITH THE FORECAST AREA BEING SOMEWHAT CAUGHT BETWEEN
THE TWO MAIN AREAS OF FORCING ASSOCIATED WITH THE AFOREMENTIONED
WAVES. THIS WILL MEAN SUNDAY WILL BE A FOGGY DAY WITH OVERCAST
SKIES...BUT THE BULK OF THE MEASURABLE PRECIP WILL REMAIN OUTSIDE
OF THE AREA ON SUNDAY. THE EXCEPTION WILL BE THE EASTERN FORECAST
AREA TOWARD EAU CLAIRE...WHICH WILL BE ON THE WESTERN EDGE OF THE
H85 MOISTURE TRANSPORT.
ON SUNDAY NIGHT...COLDER AIR BEGINS TO INFILTRATE THE AREA AS THE
PARENT SURFACE LOW LIFTS TO LAKE SUPERIOR. THE TWO PRIMARY
CONCERNS AS THIS OCCURS WILL BE VERY STRONG WINDS AND SNOW/BLOWING
SNOW. THE HIGHEST WINDS ARE FORECAST IN THE TYPICAL WEST/SOUTH
CENTRAL MN AREAS...WHERE MODELS INDICATE 40-45KTS AT THE TOP OF
THE CHANNEL. THE STRONGER FORCING FOR SNOW IS FORECAST TO BE A BIT
REMOVED FROM THE STRONGER WINDS /NORTHERN MN/WI/...SO IT REMAINS
TO BE SEEN HOW SIGNIFICANT VISIBILITY REDUCTIONS WILL BE GIVEN THE
SNOWPACK WILL HAVE ENDURED MELTING/RE-FREEZING/DRIZZLE.
WINDS SETTLE DOWN ON TUESDAY...THEN 850 MB TEMPS REDUCE TO AROUND
-15C LATE WEDNESDAY. ANOTHER WEAK WAVE CLIPS THE AREA ON
WEDNESDAY...BRINGING 20-30 PERCENT SNOW CHANCES. THESE VALUES
ARE AROUND 2 STANDARD DEVIATIONS BELOW NORMAL...AND TRANSLATE TO A
CHILLY THANKSGIVING DAY WITH HIGHS IN THE UPPER SINGLE DIGITS TO
MID TEENS. TEMPS REBOUND NICELY ON FRIDAY HOWEVER...WHEN HIGHS ARE
EXPECTED TO WARM INTO THE LOW/MID 20S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1148 AM CST SAT NOV 22 2014
IFR AND LOWER STRATUS CONTINUES TO SLOWLY CRAWL NW ACROSS
MN...STILL QUESTIONABLE WHETHER OR NOT IT REACHES AXN...BUT WITH
12Z TAF HAVING IT GETTING THERE...KEPT THAT TREND GOING. THESE
CIGS WILL ONLY MARGINALLY IMPROVE THROUGH THE AFTERNOON...LIKELY
JUST GOING FROM LIFR TO IFR BEFORE GOING BACK TO LIFR TONIGHT.
GIVEN CONTINUED SOUTH WINDS AND INCREASING MOISTURE OVER THE SNOW
THROUGH THE NIGHT...KEPT THE TREND FOR FG TONIGHT FROM 12Z TAFS
GOING. UNCERTAINTY STARTS TO INCREASE TOMORROW WITH THE POTENTIAL
FOR CIGS TO QUICKLY GO VFR. FOR NOW...TIMED IMPROVEMENT IN CIGS TO
WHEN WINDS ARE FORECAST TO SWING AROUND TO 240 DEGS OR GREATER.
SREF MVFR CIG PROBABILITY DROPS TO NEAR ZERO SUNDAY MORNING OUT
WEST...SO WE COULD VERY WELL SEE CIGS IMPROVE FASTER THAN
CURRENTLY INDICATED ACROSS MN. FOR PRECIP...LOOKING LIKE OUR BEST
CHANCE THIS TAF PERIOD WILL BE WITH A NARROW BAND OF RAIN THE
NMM/ARW/GFS/SREF SHOW COMING OUT OF SODAK LATE TONIGHT AND WORKING
ACROSS MN DURING THE MORNING.
KMSP...CONFIDENCE IS HIGH IN MINIMAL IMPROVEMENTS TO CIGS/VIS
THROUGH THE DAY. CONTINUED MOIST SRLY FLOW WILL ALSO LEAD TO A
LOWERING IN CONDITIONS TONIGHT...THOUGH THERE IS LESS CONFIDENCE
IN THE TIMING ON WHEN CIGS DROP BACK BELOW 005. 50/50 CONFIDENCE
ON THE FOG TEMPO GROUP...BUT WITH IT ALREADY IN THE TAF...LEFT IT
THERE. CONFIDENCE IS CONSIDERABLY LOWER THIS FAR OUT WITH
IMPROVEMENTS IN THE TAF BY SUNDAY AFTERNOON...BUT FOLLOWED THE
IDEA OF THE NAM/SREF ON THAT FOR NOW.
/OUTLOOK FOR KMSP/
MON...MVFR/IFR CIGS CHC -SN. WINDS NW 20G30 KT.
TUE...VFR. WINDS W 5-10 KT.
WED...MVFR/IFR CHC -SN. WINDS NW 10KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...SPD
LONG TERM...LS
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
347 PM CST Sat Nov 22 2014
.SHORT TERM: (Through Late Tonight)
Issued at 347 PM CST Sat Nov 22 2014
Scattered showers are already moving across the southern half the
CWA this afternoon in an area of modest 925-850mb moisture
convergence ahead of the trough currently over the southern High
Plains. Expect rain to become more widespread late this afternoon
into the early evening hours over the southern two thirds of the CWA
as the showers currently over southwest Missouri continue to move
northeast into the area. This is being forced by an area of
stronger low level moisture convergence that the HRRR shows moving
across the area between 22-03Z. While there will still continue to
be scattered showers elsewhere behind this area through late
evening, it still appears that better chances for more widespread
rain will move in from the west after midnight. By that time, large
scale ascent and moisture convergence will be increasing ahead of the
aforementioned southern Plains trough that will be ejecting
northeastward ahead of longwave trough. With clouds and warm air
advection tonight, stayed with lows that were close to going
temperatures and MOS guidance.
Britt
.LONG TERM: (Sunday through Next Saturday)
Issued at 347 PM CST Sat Nov 22 2014
Rain and a few thunderstorms are expected on Sunday as a southern
stream, negatively tilted shortwave moves from eastern TX
northeastward into the TN and OH Valley regions, while a northern
stream upper level trough/low moves slowly east southeastward
through the northern Plains. The models were depicting upper level
divergence over our area between a strong upper level jet streak
across the southern Plains and a weaker upper level jet streak over
the Great Lakes region. The models have some discrepencies as to
the exact track of the deepening surface low, but at this time it
appears that it will move northeastward through or just north of the
STL area around 00z Monday. There will be ample instability for at
least isolated thunderstorms on Sunday into Sunday evening,
especially across southeast MO and southwest IL. Strong low level
cold air advection can be expected Sunday night after the passage of
the low and trailing cold front. The threat for precipitation will
continue Sunday night as shortwaves rotate through our area south of
the main upper level low/trough over the northern Plains. As the
colder air filters southeastward into the region the rain may change
over to light snow before ending late Sunday night/early Monday
morning across portions of northeast and central MO as well as west
central IL. Most of the precipitation will shift east of our
forecast area by Monday, although there may be some lingering light
snow or flurries mainly across west central IL. Much colder
temperatures can be expected for Monday, with nearly steady
temperatures, mainly in the middle 30s to lower 40s as the NAM and
ECMWF models drop the -8 degree C 850 mb isotherm southward to STL.
The GFS model is even colder and quicker bringing the colder air
southeastward into our forecast area. An unseasonably cold period
is expected through Tuesday night as a large amplitude positively
tilted upper level trough moves eastward through the central US.
The GFS and ECMWF models are still hinting at the possibility of a
northwest flow shortwave and associated weak surface low to bring a
quick shot of rain/snow to our area late Tuesday night and
Wednesday. The models, particularly the GFS are not as cold for
Thanksgiving Day with the coldest air remaining just north of our
forecast area, although a strong surface ridge is still forecast to
build southeastward into the region from the northern Plains on
Thanksgiving.
GKS
&&
.AVIATION: (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1235 PM CST Sat Nov 22 2014
Have added tempo groups for showers later this afternoon and early
this evening at the STL metro TAF sites as an area of showers over
southwest Missouri moves northeast. MVFR ceilings are expected
through 10-15Z when a steadier rain is expected to develop. Once
this steady rain moves into the area, IFR conditions are expected
on Sunday at all TAF sites.
Specifics for KSTL: Expect ceilings between 2000-3000ft through
22Z. Then an area of showers will move into the terminal from the
southwest which may cause ceilings to fall below 2000ft into the
early evening hours. Then expect most of the night to be dry with
just scattered showers in the area before lower ceilings and more
widespread showers move into the area after 09Z, with steady rain
and IFR conditions moving into the area by mid morning Sunday.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1235 PM CST Sat Nov 22 2014
.UPDATE:
Issued at 1234 PM CST Sat Nov 22 2014
Have updated forecast to include area of showers and isolated
thunderstorms that have moved into southeast Missouri as well as
far southwest Illinois. HRRR is also showing that area of showers
over far southwest Missouri will move into east central Missouri
and adjacent parts of Illinois late this afternoon and early this
evening. Increased chances to likely in both these locations.
Temperatures have already climbed into upper 50s and lower 60s in
most areas, so have increased high temperatures accordingly.
Britt
&&
.SHORT TERM: (Through Late This Afternoon)
Issued at 322 AM CST Sat Nov 22 2014
Main area of precipitation has moved out of region, though there is
some widely scattered activity as well as drizzle over northern
portions of forecast area early this morning. Next shortwave to
slide northeast through forecast area today, but precipitation will
continue to be scattered in nature. Some elevated instability over
southern portions of region this afternoon, so still could see
isolated thunder in this area. Otherwise, just scattered showers
under cloudy skies. Temperatures to be near normal or just above
normal in the mid 50s to low 60s.
Byrd
.LONG TERM: (Tonight through Friday)
Issued at 322 AM CST Sat Nov 22 2014
(Tonight-Monday)
Overall forecast trends still looking pretty good, and main
changes will be an attempt to fine-tune these trends.
This afternoon`s expected scattered coverage will likely linger into
this evening, but precipitation threat should ramp up considerably
late tonight and into Sunday as dynamics from strong upper system
working northeast from the southern plains and increasing moisture
begin to come into phase over the region. Like the trends suggested
by 00z model QPFs that by Sunday morning main focus of rain will
stretch from southwest into northeast Missouri, with this band of
rain then expanding and working east during the day. With the above
trends in mind, I`ve also attempted to minimize PoPs in our far e
counties until Sunday afternoon, as moisture and lift will be
somewhat limited in this part of the FA until then. Although
instability is progged by all models to remain quite limited due to
saturated AMS I`ve continued a mention of thunder over the Ozarks
tonight and into the southeast half of the CWA on Sunday.
All of the 00z output is continuing to suggest that as dynamics with
the first system pushes into the Ohio Valley on Sunday evening, a
secondary area of precip should develop in its wake as another
shortwave drops into the base of the longwave trof. Ptypes could
become an issue by late Sunday night on the back edge of this round
of precip as southward surge of cold air will be causing the
freezing levels to drop; however at this time not expecting any
major issues as forecast soundings suggest ams will get cold enough
to support snow just as the precip begins to wind down. Threat of
measurable precip with this secondary shortwave should come to an
end on Monday morning, although we do anticipate that some flurries
will linger into the afternoon over northern sections of the CWA
where cold advection and cyclonic low level flow will be the
strongest.
Today`s moderation in temps will persist into Sunday, but return
of cold air will mean more below average temperatures for the
start of the new week.
(Tuesday-Friday)
Surface ridge is expected to work across the region on Tuesday,
giving the FA chilly but dry late November weather. It still
appears that another fast moving shortwave digging into
progressive longwave trof will produce a quick shot of lift across
the region by Wednesday, but strongest dynamics will be north of
our area and moisture will be quite limited, so going slight
chance/low chance PoPs still look good at midweek.
Medium range solutions still leaving questions regarding sensible
weather trends heading into the Thanksgiving holiday. GFS is now
supported by the GEM in suggesting much less deepening of the
longwave trof over the eastern CONUS. This keeps baroclinicity
further north and allows the next fast moving shortwave to interact
with this thermal gradient, which would suggest a threat of some
light precip on Thanksgiving over northern sections of the CWA.
ECMWF is still deeper with the trof to our east, but its interesting
that its not as deep as was suggested in yesterday`s guidance, and
in fact has trended a bit more towards a flatter mid level flow.
For now will maintain dry forecast, but this trend will be
interesting to watch over the next few forecast cycles.
With the reintensification of the trof over the eastern CONUS temps
will remain well below normal during the latter half of the
upcoming work week, although exact extent of the cold will
obviously depend on the intensity of the trof. Highs primarily in
the 30s heading into Thursday and Friday look like a good starting
point for now.
Truett
&&
.AVIATION: (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1235 PM CST Sat Nov 22 2014
Have added tempo groups for showers later this afternoon and early
this evening at the STL metro TAF sites as an area of showers over
southwest Missouri moves northeast. MVFR ceilings are expected
through 10-15Z when a steadier rain is expected to develop. Once
this steady rain moves into the area, IFR conditions are expected
on Sunday at all TAF sites.
Specifics for KSTL: Expect ceilings between 2000-3000ft through
22Z. Then an area of showers will move into the terminal from the
southwest which may cause ceilings to fall below 2000ft into the
early evening hours. Then expect most of the night to be dry with
just scattered showers in the area before lower ceilings and more
widespread showers move into the area after 09Z, with steady rain
and IFR conditions moving into the area by mid morning Sunday.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS GLASGOW MT
323 PM MST SAT NOV 22 2014
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH MONDAY...
THIS AFTERNOON...A STRONG SURFACE LOW PRESSURE SYSTEM HAS DRAWN A
COLD FRONT THROUGH NORTHEAST MONTANA. WEST WINDS BEHIND THE SYSTEM
HAVE BEEN QUITE STRONG...TOPPING 30 MPH IN PLACES NEAR THE WESTERN
EDGE OF THE CWA. 750MB WINDS ARE QUITE STRONG AND SOME CLEARING
SKIES OUT WEST HAVE ALLOWED SOMEWHAT BETTER MIXING IN THAT AREA.
WINDS SHOULD EASE A LITTLE BIT AFTER DARK...HOWEVER...STRONG
SURFACE PRESSURE GRADIENT WILL KEEP WINDS IN THE MODERATE TO
STRONG LEVEL TONIGHT AND THROUGH TOMORROW AFTERNOON. WINDS WILL
VEER MORE NORTHERLY TONIGHT WITH STRONGER COLD ADVECTION.
INITIAL ROUND OF LIGHT RAIN SHOWERS HAS MOVED OFF EAST OF THE
AREA WITH SNOW SHOWERS EXPECTED THIS EVENING COMING DOWN FROM THE
NORTH ALONG THE CANADIAN BORDER. CLEARING BEHIND THIS INITIAL WAVE
IS RELATED TO Q-VECTOR DIVERGENCE AND DRY SLOT BEHIND POSITIVE
VORTICITY ADVECTION AREA. SNOW SHOWERS ARE IN WRAP AROUND AREA
AND OCCUR WITH COLD AIR ADVECTION TONIGHT. SNOW AMOUNTS ARE NOT
EXPECTED TO BE GREAT...WITH ANYWHERE FROM A HALF INCH TO 2 INCHES
EXPECTED THROUGH SUNDAY. HIGH RESOLUTION MODELS HAVE LESS SNOW
THAN THE SYNOPTIC MODELS. THE HRRR HAS ALMOST NONE. THE NAM...ON
THE OTHER HAND...HAS SOME LOCALIZED AREAS OF MODERATE SNOW. WITH
STRONG WINDS...AN INCH OF SNOW COULD BLOW AROUND ENOUGH TO CAUSE
TRAVEL DIFFICULTIES...SO ISSUED AN ADVISORY FOR BLOWING SNOW.
SYSTEM PROGRESSES FAIRLY QUICKLY EASTWARD AND SHOWERS LOOK TO END
LATE SUNDAY AFTERNOON. MARTIN
.LONG TERM...MONDAY NIGHT THROUGH SATURDAY...
THE EXTENDED PERIOD WILL SEE A LONG-WAVE TROUGHS OVER THE EAST HALF
OF THE NATION AND CANADA. THESE TROUGHS WILL BE ANCHORED BY THE
PERSISTENT ARCTIC LOW OVER THE NUNAVUT TERRITORY OF CANADA. THIS
LOW WILL SEE SHORT-WAVE TROUGH ROTATE AROUND THE MAIN LOW CENTER.
THESE SHORT-WAVES WILL LARGELY DETERMINE TEMPERATURES FOR NORTHEAST
MONTANA THROUGH THE EXTENDED PERIOD. OFF TO THE WEST THERE WILL BE
AN EQUALLY PERSISTENT RIDGE THAT WILL LARGELY MAINTAIN NORTHWEST
FLOW ALOFT FOR OUR REGION.
TUESDAY EVENING NORTHEAST MONTANA WILL BE ON THE COLD SIDE OF THE
BOUNDARY BETWEEN THE WESTERN AND EASTERN AIR-MASSES. THERE WILL BE
MOVEMENT OF A SHORT-WAVE EXTENDING FROM THE CANADIAN LOW. IN
COINCIDENCE WILL BE A DISTURBANCE RIDGING OVER THE TOP OF THE RIDGE.
THE ACTION BETWEEN THESE TWO DISTURBANCES WILL AT FIRST BE A
SIGNIFICANT AMOUNT OF MOISTURE OVERRIDING THE LENGTH OF THE
BOUNDARY. THIS WILL PRODUCE RAIN OF THE WARM SIDE AND WINTRY MIX
ON THE EAST SIDE. THE MAIN FORECAST CHALLENGE OF THE EXTENDED
PERIOD WILL BE THE LOCATION OF THE BOUNDARY IN RELATION TO
NORTHEAST MONTANA. A DIFFERENCE OF JUST A FEW HUNDRED MILES WILL
MAKE A LARGE DIFFERENCE IN TEMPERATURES.
TUESDAY...BOTH THE GFS AND EC PLACE THE BOUNDARY JUST TO OUR WEST
WHICH WILL LEAD TO SLIGHTLY COOLER THAN NORMAL TEMPERATURES. THE
OVERRUNNING MOISTURE ALSO APPEARS TO BE RUNNING PRECIPITATION TO
OUR WEST.
TUESDAY NIGHT AND WEDNESDAY...THE BOUNDARY DRIFTS EAST AND
TIGHTENS PRECIPITATION SPREADS ACROSS NEMONT. THE PRECIPITATION
TYPE WILL BE DIFFICULT TO DETERMINE THIS FAR OUT...BUT IT WILL
LIKELY BE RAIN IN THE WEST AND SNOW IN THE NORTHEAST...WITH A
WINTRY MIX IN THE MIDDLE.
KEEPING IN MIND THAT THE MODELS HAVE BEEN GOING IN AND OUT OF
AGREEMENT...TEMPERATURES AND WX HAVE SOME UNCERTAINTY. BUT FOR
NOW SNOW AMOUNTS SUGGEST WINTER HEADLINES FOR THE MIDDLE OF NEXT
WEEK... WITH SNOW AMOUNTS RANGING FROM 1 TO 4 INCHES BY
THANKSGIVING MORNING.
THANKSGIVING DAY...BOTH MODELS SUGGEST ANOTHER COLD WAVE ROUNDING
THE ARCTIC LOW THAT WILL BACKDOOR ANOTHER COLD FRONT INTO NEMONT.
THIS WILL TURN THE PRECIPITATION TO ALL SNOW...MAINLY IN THE
SOUTHWEST PORTION OF THE CWA AND BRING ABOUT COLDER TEMPERATURES.
FRIDAY AND SATURDAY...THE BOUNDARY CONTINUES TO FLUCTUATE BUT WILL
LIKELY KEEP THE MAJORITY OF THE CWA IN THE COLD SECTION. THERE
WILL ALSO BE LESSOR AMOUNTS OF OVERRUNNING MOISTURE FOR ADDITIONAL
LIGHT SNOW.
SCT
PREVIOUS DISCUSSION...
MONDAY NIGHT THROUGH FRIDAY...PERSISTENT UPPER LOW OVER HUDSON
BAY AREA DURING PERIOD. UPPER LEVEL RIDGE OVER PACIFIC NW MONDAY
SLOWLY MOVES INTO NORTHERN ROCKIES AND FLATTENS OUT BY SATURDAY.
RIDGE AND ACCOMPANYING WEST WINDS PROVIDE SEASONABLY PLEASANT
TEMPERATURES TUESDAY.
WEDNESDAY SHORT WAVES SWEEPING DOWN THROUGH NORTHWEST FLOW WILL
BRING CHANCE OF RAIN AND SNOW TO NORTHEAST MONTANA. GFS40 AND
ECMWF/GFS13 BEGIN TO DIVERGE LATER WEDNESDAY HOWEVER. GFS40 DIGS
TROUGH SOUTHWARD ACROSS STATE WHILE ECMWF AND GFS13 TAKE SHORT WAVE
FURTHER EAST. WILL LEAN TOWARD MORE CONSISTENT AND DRIER ECMWF/GFS13
SOLUTIONS. BY THANKSGIVING DAY A RIDGE DEVELOPS OVER MONTANA WITH
A NORTHWEST FLOW ALOFT. EXPECT ONLY SLIGHT CHANCE RAIN AND SNOW
THROUGH REMAINDER OF PERIOD BENEATH WEAK RIDGE. TEMPERATURES WILL BE
SOMEWHAT COOLER AFTER TUESDAY AND WELL BELOW SEASONAL NORMALS.
EXPECT WINDS TO BE RELATIVELY LIGHT THROUGH THE PERIOD. BRITTON
&&
.AVIATION...
A FAST MOVING CLIPPER WILL SWEEP ACROSS THE REGION TONIGHT AND
SUNDAY MORNING. BOTH THE UPPER AND LOWER LEVEL LOWS CLOSE OFF
AND STACK UP OVER SOUTHERN SASKATCHEWAN. THE RESULTING COMPACT
CYCLONE WILL BECOME RATHER EFFICIENT IN PRODUCING VERY STRONG
WINDS TONIGHT AND SUNDAY MORNING OVER NORTHEAST MONTANA. THESE
NORTHWEST WINDS COULD RANGE FROM 20KT TO 30KT WITH GUSTS TO 45KT.
WITH LIGHT SNOW EXPECTED AND EXISTING SNOW ON THE GROUND...
BLOWING SNOW COULD BECOME AN ANOTHER ISSUE AFFECTING VISIBILITY...
ALONG WITH SNOW DRIFTS ACROSS RUNWAYS. WIND WILL TAPER OFF TO
AROUND 15KT SUNDAY AFTERNOON.
THE OTHER FEATURE OF THIS STORM WILL BE LOW-LEVEL OVERCAST...
PRODUCING MVFR/IFR CEILINGS...WITH LIGHT SNOW AT TIMES. WRAP-
AROUND SNOW COULD INCREASE THE CHANCES FOR HEAVIER...MEASURABLE
SNOW ON SUNDAY MORNING...TAPERING OFF IN THE AFTERNOON. ANY
TERMINAL WITH FALLING SNOW COULD TEMPORARILY SEE MVFR/IFR
VISIBILITIES.
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...
LAKE WIND ADVISORY UNTIL 5 PM MST SUNDAY FOR CENTRAL AND
SOUTHEAST PHILLIPS...CENTRAL AND SOUTHERN VALLEY...GARFIELD...
MCCONE...PETROLEUM.
WINTER WEATHER ADVISORY FROM 11 PM THIS EVENING TO 2 PM MST
SUNDAY FOR CENTRAL AND SOUTHEAST PHILLIPS...CENTRAL AND SOUTHERN
VALLEY...DANIELS...DAWSON...EASTERN ROOSEVELT...GARFIELD...
MCCONE...NORTHERN PHILLIPS...NORTHERN VALLEY...PRAIRIE...
RICHLAND...SHERIDAN...SOUTHWEST PHILLIPS...WESTERN ROOSEVELT...
WIBAUX.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1201 PM EST SAT NOV 22 2014
.SYNOPSIS...
FLOW BECOMES SOUTHWESTERLY TODAY...INCREASING SUNDAY FOR A WARMER
BUT WET WEEKEND. LOW PRESSURE BRINGS A WARM FRONT SUNDAY NIGHT...
FOLLOWED BY A COLD FRONT MONDAY WITH GOOD CHANCES FOR RAIN SHOWERS.
&&
.NEAR TERM /THROUGH SUNDAY/...
11AM UPDATE...ALLOWED FREEZING RAIN ADVISORY TO EXPIRE AS TEMPS
ARE QUICKLY CLIMBING ABOVE FREEZING.
PREVIOUS DISCUSSION...
LATEST RADAR TRENDS HAVE A SLUG OF MOISTURE MOVING TOWARDS WV AND
TEMPS ARE STILL IN THE MID TEENS. HRRR HAS THE SLUG DRYING OUT
EXCEPT FOR PORTIONS OF SE OHIO...SO WENT WITH A FREEZING RAIN
ADVISORY FOR A BRIEF PERIOD WHERE PRECIP WILL BE FALLING INTO A
COLD AIR MASS. OBSERVATION IN PERRY COUNTY AT 27 SO OPTED TO LEAVE
THEM OUT AS THE WARM AIR EXTENDS TO ABOUT PERRY CNTY. AFTER 9 AM
TEMPS SHOULD WARM ABOVE FREEZING AND THE FZRA THREAT WILL BE
GONE.
THEN A PLEASANT DRY...DAY WHERE TEMPERATURES REBOUND TO NORMAL.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
SHOWERS WILL CONTINUE THROUGH TO MONDAY MORNING WITH A WARM FRONT
LIFTING NORTH OVERNIGHT SUNDAY. THE WARM TEMPERATURES WILL BE SHORT
LIVED AS THE ASSOCIATED COLD FRONT MOVES EAST THROUGH THE FORECAST
AREA EARLY MONDAY. THE COLD FRONT WILL BRING ONLY A SLIGHT CHANCE
OF SHOWERS BEFORE EXITING MONDAY NIGHT. BEHIND THE FRONT...EXPECT
MOSTLY DRY BUT MUCH COOLER WEATHER.
WINDS ON MONDAY AND INTO TUESDAY WILL BE STRONG...PARTICULARLY ALONG
THE OHIO RIVER VALLEY AND AT HIGHER ELEVATIONS...WITH THE GFS
SHOWING 925MB WINDS OF UP TO 60 KTS OVER THE OHIO
VALLEY...HOWEVER...NOT CURRENTLY EXPECTING TO REACH ADVISORY
CRITERIA. WINDS SHOULD DIMINISH THROUGH THE PERIOD AS THE STRONGER
WINDS LIFT NORTH.
THE CONSRAW APPEARS TO HAVE A GOOD HANDLE ON THE NONDIURNAL
TEMPERATURES FOR MONDAY SO USED IT WITH JUST A FEW TWEAKS. LOWS
MONDAY MORNING WILL ONLY DIP INTO THE MID 50S BEFORE REACHING THE
HIGH BY AROUND 16Z.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
SHOWERS WILL BEGIN TO END ON MONDAY NIGHT AS THE TROUGH WEAKENS AND
MOVES EAST. MODEL TRENDS HAVE WAFFLED A BIT WITH NEITHER THE GFS
AND ECMWF STAYING WITH A GREAT SOLUTION. SHORTWAVES ARE MORE
EVIDENT IN DEEPER TROUGH EXHIBITED BY THE ECMWF...BUT THE GFS
CURRENTLY SHOWS A MORE WESTERN FLOW. TOOK A BLEND OF THE TWO MODELS
TO RESOLVE SOME OF THE DISAGREEMENT IN THE HOPES THE SOLUTIONS WILL
CONVERGE AS WE MOVE CLOSER IN TIME.
TEMPERATURES WILL COOL SIGNIFICANTLY BY TUESDAY WITH THE PASSAGE OF
A COLD FRONT. THESE COOLER TEMPERATURES COMBINED WITH LOW PRESSURE
MOVING EAST FROM THE GREAT LAKES WILL PROVIDE SOME OPPORTUNITY FOR
SOME SNOW SHOWERS ALONG THE OHIO RIVER EARLY
THURSDAY...TRANSITIONING TO RAIN BY AFTERNOON FOR THE LOWLANDS. THE
MOUNTAINS WILL CONTINUE TO HAVE A SLIGHT CHANCE OF SOME SNOW SHOWERS
THROUGH THE NIGHT.
&&
.AVIATION /17Z SATURDAY THROUGH WEDNESDAY/...
QUIET VFR WEATHER. A BRIEF PERIOD OF FREEZING RAIN IS POSSIBLE IN
INTERIOR SE OHIO SAT MORNING.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SUNDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: LOW CHANCE OF MVFR CIGS ACROSS INTERIOR SE OHIO
SAT MORNING AND THE NRN WV MOUNTAINS SAT MIDDAY AND AFTERNOON.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EST 1HRLY 09 10 11 12 13 14 15 16 17 18 19 20
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z SUNDAY...
IFR POSSIBLE ON EASTERN MOUNTAIN SLOPES AND ACROSS THE MIDDLE OHIO
VALLEY IN RAIN AND STRATUS LATE SUN INTO MON MORNING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/MZ
NEAR TERM...MZ
SHORT TERM...ARJ
LONG TERM...LS
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS TULSA OK
312 PM CST SAT NOV 22 2014
.DISCUSSION...
ROUND 2 OF THE PRECIP IS ONGOING OVER THE REGION TODAY...WITHIN
THE WARM CONVEYOR OF THE UPPER CYCLONE CENTERED OVER THE RIO
GRANDE VALLEY ATTM. THE LATEST HRRR MAINTAINS THIS BAND OF RAIN
FROM SE/E CNTRL OK UP INTO NW AR THIS EVENING SO POPS HAVE BEEN
ADJUSTED FOR THE 00Z TO 06Z TIME FRAME. THERE SHOULD BE ANOTHER
ROUND OF PRECIP MAINLY IN THE EAST AFTER MIDNIGHT INTO SUNDAY AS
THE UPPER SYSTEM OPENS UP AND LIFTS NORTHEAST. MODEL SOUNDINGS
SHOW VERY LITTLE INSTABILITY...MORE OR LESS MOIST ADIABATIC THRU
THE ENTIRE TROPOSPHERE. THIS HAS VERIFIED IN CURRENT
OBSERVATIONS...THE LIGHTNING ACTIVITY THAT PEAKED THIS MORNING HAS
WANED COMPLETELY OVER E OK/NW AR. WHILE I CAN`T RULE OUT AN
ISOLATED LIGHTNING STRIKE OR TWO...NOT SURE IT IS WORTHY OF
ISOLATED STORM MENTION AND THUS HAVE LEFT IT OUT FOR TONIGHT.
THE NORTHERN AND SOUTHERN STREAMS OF THE WESTERLIES ARE FORECAST
TO MERGE OVER THE NEXT 24 TO 48 HOURS...AS A DEEP LONGWAVE TROUGH
DEVELOPS OVER THE CENTRAL CONUS. AS THIS EVOLUTION IS UNDERWAY...A
STRONG SHORTWAVE TROUGH WILL DIVE SOUTHEAST OVER THE
CENTRAL/SOUTHERN PLAINS SUNDAY AFTERNOON AND EVENING. STRONG LOW-
MID LEVEL COLD FRONTOGENESIS AND QG LIFT WILL FOCUS A BAND OF
PRECIP FROM NE OK INTO NW AR...WITH THE BEST CHANCES NEAR THE KS
AND MO BORDERS. LOW TO MID LEVEL LAPSE RATES STEEPEN DURING THE
AFTERNOON...WITH THE NAM SHOWING 500-800 J/KG OF MUCAPE. HAVE
THROWN IN THUNDER MENTION FOR SUNDAY AFTERNOON AND EVENING BASED
ON THIS DATA. ONCE THIS SYSTEM PASSES US BY...THE FORECAST WILL BE
DRY THRU DAY 7.
MILD TONIGHT AND TOMORROW THEN TEMPS WILL TAIL OFF TO NEAR OR
SLIGHTLY BELOW AVERAGE EARLY NEXT WEEK. SHOULD SEE ANOTHER WARMING
TREND MIDWEEK AHEAD OF A SHALLOW COLD SURGE BY THE END OF NEXT
WEEK. THANKSGIVING WEEKEND TRAVEL STILL LOOKS OK BASED ON TODAY`S
DATA.
LACY
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 56 64 35 55 / 50 50 20 10
FSM 55 71 39 55 / 80 50 10 10
MLC 57 68 37 58 / 80 20 10 10
BVO 55 64 34 54 / 50 70 20 10
FYV 54 66 34 49 / 80 70 50 10
BYV 53 65 35 49 / 80 80 50 10
MKO 55 67 35 54 / 70 40 30 10
MIO 54 65 34 51 / 70 80 50 10
F10 55 66 36 56 / 80 30 20 10
HHW 57 71 38 59 / 80 10 10 10
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
LONG TERM....30
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1149 AM CST SAT NOV 22 2014
.UPDATE...
18Z TAF DISCUSSION.
&&
.AVIATION...
VFR CONDITIONS EXPECTED TODAY WITH SCT STRATOCU AND BRISK SOUTH
WINDS WITH GUSTS TO AROUND 20 KTS IN AFTERNOON. CIGS BECOME MVFR
BY 23/10Z AND IFR BY 23/15Z AS STRONG MOISTURE ADVECTION
COMMENCES DUE TO POWERFUL SURFACE LOW TAKING SHAPE TO OUR WEST.
-SHRA NOT ANTICIPATED UNTIL AROUND 15Z AT ALL AIRPORTS...WITH
STRONG SE WINDS WITH GUSTS UP TO 30 KTS DEVELOPING BY END OF TAF
PERIOD.
SHAMBURGER
&&
.PREV DISCUSSION... /ISSUED 933 AM CST SAT NOV 22 2014/
UPDATE...
LATEST RADAR IMAGERY SHOWS A FEW LIGHT RAIN SHOWERS AND SPRINKLES
CONTINUE ACROSS NORTHWEST PARTS OF THE MID STATE. HRRR INDICATES
THIS ACTIVITY WILL CONTINUE THROUGH AROUND 18Z...SO EXPANDED
SLIGHT CHANCE POPS A BIT EASTWARD AND EXTENDED THROUGH THAT TIME.
PRECIP SHOULD MOVE OUT BY AFTERNOON WITH PARTLY CLOUDY SKIES AND
MUCH WARMER TEMPERATURES WITH HIGHS IN THE LOWER 60S. REST OF
FORECAST LOOKS GOOD AND ONLY MINOR TWEAKS WERE MADE.
SHAMBURGER
PREV DISCUSSION... /ISSUED 537 AM CST SAT NOV 22 2014/
UPDATE...FOR 12Z AVIATION FORECASTS.
AVIATION...
A FEW MORNING SPRINKLES IN NORTHWEST COUNTIES/CKV...OTHERWISE NO
PRECIPITATION TODAY. EXTENSIVE MID AND HIGH CLOUDS WILL CONTINUE
STREAMING ACROSS MIDDLE TN AHEAD OF A UPPER LEVEL STORM SYSTEM
THAT WILL APPROACH LATE TONIGHT AND SUNDAY. SFC WINDS WILL PICK UP
A LITTLE TODAY AS GRADIENTS TIGHTEN.
INCREASING MOISTURE WILL HELP DEVELOP LOW CLOUDS AFTER 00Z TONIGHT.
MVFR CIGS POSSIBLE AT BNA AND CKV TOWARD 12Z SUNDAY. HIGH CHANCE OF
RAIN AND MVFR/IFR CIGS SHORTLY AFTER THIS FORECAST CYCLE ENDS AT
12Z SUNDAY.
PREV DISCUSSION... /ISSUED 416 AM CST SAT NOV 22 2014/
DISCUSSION...
THE SURFACE RIDGE THAT HAS KEPT US DRY ACROSS THE MID-STATE THE LAST
COUPLE OF DAYS HAS MOVED OFF TO THE EAST. NOW SITTING OVER THE
MID-ATLANTIC STATES...IT HAS PUT THE SOUTHEAST U.S. INTO A
SOUTHEASTERLY BOUNDARY LAYER FLOW. COUPLED WITH A WEAK MID-LEVEL
DISTURBANCE MOVING ENE THROUGH THE MID-MISSISSIPPI/TN/OHIO
VALLEYS...THERE ARE A FEW SHOWERS ON THE RADAR. THE CATCH IS...IT`S
BEEN SO DRY AND THE ATMOSPHERE IS TAKING SO LONG TO SATURATE THAT
NOT MUCH OF THIS RAIN IS REACHING THE GROUND. KCKV SHOWED LIGHT
RAIN A COUPLE OF HOURS AGO...BUT THEY ONLY MEASURED A TRACE. THESE
RADAR REFLECTIVITIES SHOULD MOVE OFF TO THE NE THROUGH THE MORNING
HOURS...LEAVING PARTLY TO MOSTLY CLOUDY CONDITIONS ACROSS THE
STATE. THE MOST INTERESTING PART OF THE DAY WILL BE THE WINDS AS
THE PRESSURE GRADIENT TIGHTENS ACROSS MIDDLE TN. IT WILL BE BREEZY
AND MOST EVERYONE WILL WARM INTO THE 60S TODAY WITH MIDDLE TO UPPER
50S ON THE PLATEAU.
ALREADY IN ITS BEGINNING STAGES...AN INTENSE SHORTWAVE TROUGH IS
EXPECTED TO DEVELOP OVER THE DESERT SOUTHWEST TODAY. THIS SYSTEM
WILL BE OUR WEATHER MAKER ON SUNDAY. IN RESPONSE TO THIS SYSTEM
ROUNDING THE BASE OF THE LONGWAVE PATTERN...A SURFACE LOW WILL
DEVELOP OVER E TEXAS TONIGHT...MOVING NEWD...AND PASSING JUST TO THE
WEST OF US. UNFORTUNATELY...THIS PUTS US IN A PRECARIOUS POSITION.
THE UPPER LEVEL TROUGH SWINGS INTO A NEGATIVE TILT SUNDAY MORNING
AND BECAUSE OF THIS...THE SURFACE LOW DEEPENS PRETTY RAPIDLY. THIS
WILL RESULT IN A COUPLE OF THINGS...FIRST...IT WILL BE WINDY
SUNDAY. WHILE TODAY`S BREEZY CONDITIONS WILL RELAX A BIT TONIGHT...
THE SURFACE PRESSURE GRADIENT TIGHTENS BACK UP SIGNIFICANTLY AND WE
COULD SEE SUSTAINED WINDS OF 15-25 MPH WITH GUSTS TO 35 OR 40 MPH
ON SUNDAY. THIS WILL PUT US ON THE BRINK OF A WIND ADVISORY...
BUT THIS LIKELY WON`T BE ISSUED UNTIL LATER TODAY OR EVEN TONIGHT.
A SECOND RESULT OF THE QUICK INTENSIFICATION OF THIS SYSTEM IS THE
AMOUNT OF WIND SHEAR THAT WILL ENSUE. DEEP LAYER SHEAR OF 50-70
KTS IS LIKELY AND 0-3KM SRH VALUES OF 800-1000 M^2/S^2 MAY ALSO
OCCUR. THIS AMOUNT OF WIND SHEAR MIGHT ACTUALLY BE OUR SAVING
GRACE. BECAUSE OF THE SOUTHEAST BOUNDARY LAYER FLOW OVER THE NEXT
24-36 HOURS...RETURN MOISTURE SHOULD BE FAIRLY MODERATE AHEAD OF
THIS SYSTEM THIS FAR NORTH. IN FACT...THE 60 DEGREE DEW POINT LINE
SHOULD REMAIN SOUTH OF US. WITH SO MUCH WIND SHEAR AND RELATIVELY
LITTLE INSTABILITY...WE SHOULD REMAIN NORTH OF ANY WIDESPREAD
SEVERE WEATHER THREAT. WHAT WILL BE OF CONCERN IS THE 850MB JET
THAT IS PROGGED TO DEVELOP SUNDAY MORNING THAT COULD BE AS STRONG
AS 50 TO 75 KTS. THIS MEANS WE CAN`T RULE OUT THE POTENTIAL FOR AN
ISOLATED STRAIGHT LINE WIND THREAT WITH ANY THUNDERSTORMS THAT
DEVELOP. I WILL GO AHEAD AND HIGHLIGHT THIS ISOLATED WIND THREAT
IN THE HAZARDOUS WEATHER OUTLOOK THIS MORNING FOR SUNDAY...BUT
THIS SHOULD NOT BE A WIDESPREAD SEVERE WEATHER EVENT.
FROPA WILL BE A LITTLE DELAYED WITH THIS SYSTEM...OCCURRING THROUGH
THE MORNING HOURS ON MONDAY. SOME LIGHT RAIN MAY RESULT...BUT THE
BULK OF THE ACTIVITY SHOULD BE ON SUNDAY.
BELOW NORMAL TEMPERATURES WILL RETURN FOR THE REMAINDER OF THE
WEEK. DAYTIME HIGHS IN THE 40S ARE EXPECTED BY TUESDAY...WITH
OVERNIGHT LOWS IN THE 20S AND 30S...BUT WE SHOULD REMAIN DRY
THROUGHOUT THE WEEK.
UNGER
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
55
AREA FORECAST DISCUSSION...CORRECTED
NWS AUSTIN/SAN ANTONIO TX
349 PM CST SAT NOV 22 2014
...THE RISK OF SEVERE WEATHER AND HEAVY RAIN CONTINUES
THROUGH THIS EVENING...
.SHORT TERM (TONIGHT THROUGH SUNDAY NIGHT)...
STRONG STORMS AND HEAVY RAIN WILL CONTINUE TO AFFECT MAINLY THE
EASTERN HALF OF SOUTH CENTRAL TEXAS FOR THE NEXT SEVERAL HOURS.
THE THREAT FOR STRONG TO SEVERE WEATHER STILL EXISTS THROUGH THIS
EVENING. A SECOND ROUND OF SHOWERS AND STORMS CURRENTLY ONGOING
ACROSS THE SERRANIAS DEL BURRO (NORTHEAST MEXICO) IS FORECAST TO
PUSH EASTWARD AND ACROSS MOST OF SOUTH CENTRAL TEXAS THIS EVENING.
THE HRRR AND TECH-TECH HIRES MODELS DEVELOP AN MCS AROUND 23Z/5 PM
THIS AFTERNOON WHILE A LINE OF SHOWERS AND STORMS FORM AHEAD OF A
SURFACE CONVERGENCE ZONE (WARM SECTOR). IF THIS SCENARIO PANS
OUT...STRONG TO SEVERE STORMS ARE POSSIBLE ACROSS THE RIO
GRANDE...ESPECIALLY ALONG AND WEST OF ROCKSPRINGS TO HONDO TO
PEARSALL LINE. A SEVERE THUNDERSTORM WATCH IS IN EFFECT THROUGH 10
PM TONIGHT FOR THE AREA ABOVE MENTIONED. MAIN WEATHER THREATS WILL
BE LARGE HAIL AND DAMAGING WINDS. CAN`T RULE OUT AN ISOLATED
TORNADO OR TWO. SOME OF THESE STRONG STORMS WILL PRODUCE HEAVY
DOWNSPOURS WITH RAINFALL ACCUMULATIONS UP TO ONE INCH PER HOUR.
THE MCS IS FORECAST TO COMBINE WITH THE SHOWERS AND STORMS
EXPECTED TO FORM ALONG THE CONVERGENCE ZONE AND MOVE EAST IN A
LINEAR FASHION...AFFECTING THE I-35 CORRIDOR AROUND 8 OR 9 PM THIS
EVENING. BY 9 PM...THE SYSTEM IS LIKELY TO TRANSITION TO A HEAVY
RAIN PRODUCER WITH STRONGER STORMS CAPABLE OF PRODUCING LARGE
HAIL. THE LINE OF STORMS WILL QUICKLY PUSH TO THE EAST BY MIDNIGHT
TONIGHT WITH RAIN CHANCES COMING TO AN END ACROSS THE ENTIRE AREA
BY 2 OR 3 AM SUNDAY. NEW RAINFALL AMOUNTS FOR THE TONIGHT PERIOD
COULD RANGE FROM 1 TO 2 INCHES AND UP TO 3 INCHES IN ISOLATED
PLACES.
ON SUNDAY...EXPECT MOSTLY SUNNY/CLEAR SKIES ACROSS SOUTH CENTRAL
TEXAS WITH BREEZY CONDITIONS. A PACIFIC COLD FRONT WILL PUSH
ACROSS THE REGION SUNDAY NIGHT INTO MONDAY.
&&
.LONG TERM (MONDAY THROUGH SATURDAY)...
THE WEATHER IS EXPECTED TO BE FAIRLY QUIET FOR MUCH OF NEXT WEEK. A
WEAK FRONT WILL MOVE THROUGH THE AREA OVERNIGHT SUNDAY. THIS FRONT
IS IN RESPONSE TO AN UPPER LEVEL TROUGH MOVING THROUGH THE PLAINS.
THE WEATHER FOR THANKSGIVING SHOULD BE PRETTY SEASONAL WITH HIGHS
IN THE 60S AND LOWS IN THE 30S/40S.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 55 78 45 64 40 / 60 0 - - -
AUSTIN BERGSTROM INTL AIRPORT 54 77 43 64 37 / 70 0 - - -
NEW BRAUNFELS MUNI AIRPORT 55 79 45 66 40 / 60 0 - - -
BURNET MUNI AIRPORT 52 75 42 62 38 / 50 0 - - -
DEL RIO INTL AIRPORT 50 78 46 65 38 / 20 0 - - -
GEORGETOWN MUNI AIRPORT 54 75 43 62 38 / 60 0 - - -
HONDO MUNI AIRPORT 49 77 42 65 37 / 50 0 - - -
SAN MARCOS MUNI AIRPORT 53 78 44 65 39 / 70 0 - - -
LA GRANGE - FAYETTE REGIONAL 57 78 46 64 40 / 90 0 - - -
SAN ANTONIO INTL AIRPORT 54 78 46 66 41 / 50 0 - - -
STINSON MUNI AIRPORT 54 79 46 66 41 / 60 0 - - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...24
SYNOPTIC/GRIDS...17
PUBLIC SERVICE/DATA COLLECTION...00
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
339 PM CST SAT NOV 22 2014
...THE RISK OF SEVERE WEATHER AND HEAVY RAIN CONTINUES
THROUGH THIS EVENING...
.SHORT TERM (TONIGHT THROUGH SUNDAY NIGHT)...
STRONG STORMS AND HEAVY RAIN WILL CONTINUE TO AFFECT MAINLY THE
EASTERN HALF OF SOUTH CENTRAL TEXAS FOR THE NEXT SEVERAL HOURS.
THE THREAT FOR STRONG TO SEVERE WEATHER STILL EXISTS THROUGH THIS
EVENING. A SECOND ROUND OF SHOWERS AND STORMS CURRENTLY ONGOING
ACROSS THE SERRANIAS DEL BURRO (NORTHEAST MEXICO) IS FORECAST TO
PUSH EASTWARD AND ACROSS MOST OF SOUTH CENTRAL TEXAS THIS EVENING.
THE HRRR AND TECH-TECH HIRES MODELS DEVELOP AN MCS AROUND 23Z/5 PM
THIS AFTERNOON WHILE A LINE OF SHOWERS AND STORMS FORM AHEAD OF A
SURFACE CONVERGENCE ZONE (WARM SECTOR). IF THIS SCENARIO PANS
OUT...STRONG TO SEVERE STORMS ARE POSSIBLE ACROSS THE RIO
GRANDE...ESPECIALLY ALONG AND WEST OF ROCKSPRINGS TO HONDO TO
PEARSALL LINE. A SEVERE THUNDERSTORM WARNING IS IN EFFECT THROUGH
10 PM TONIGHT FOR THE AREA ABOVE MENTIONED. MAIN WEATHER THREATS
WILL BE LARGE HAIL AND DAMAGING WINDS. CAN`T RULE OUT AN ISOLATED
TORNADO OR TWO. SOME OF THESE STRONG STORMS WILL PRODUCE HEAVY
DOWNSPOURS WITH RAINFALL ACCUMULATIONS UP TO ONE INCH PER HOUR.
THE MCS IS FORECAST TO COMBINE WITH THE SHOWERS AND STORMS
EXPECTED TO FORM ALONG THE CONVERGENCE ZONE AND MOVE EAST IN A
LINEAR FASHION...AFFECTING THE I-35 CORRIDOR AROUND 8 OR 9 PM THIS
EVENING. BY 9 PM...THE SYSTEM IS LIKELY TO TRANSITION TO A HEAVY
RAIN PRODUCER WITH STRONGER STORMS CAPABLE OF PRODUCING LARGE HAIL.
THE LINE OF STORMS WILL QUICKLY PUSH TO THE EAST BY MIDNIGHT
TONIGHT WITH RAIN CHANCES COMING TO AN END ACROSS THE ENTIRE AREA
BY 2 OR 3 AM SUNDAY. NEW RAINFALL AMOUNTS FOR THE TONIGHT PERIOD
COULD RANGE FROM 1 TO 2 INCHES AND UP TO 3 INCHES IN ISOLATED PLACES.
ON SUNDAY...EXPECT MOSTLY SUNNY/CLEAR SKIES ACROSS SOUTH CENTRAL
TEXAS WITH BREEZY CONDITIONS. A PACIFIC COLD FRONT WILL PUSH
ACROSS THE REGION SUNDAY NIGHT INTO MONDAY.
&&
.LONG TERM (MONDAY THROUGH SATURDAY)...
THE WEATHER IS EXPECTED TO BE FAIRLY QUIET FOR MUCH OF NEXT WEEK. A
WEAK FRONT WILL MOVE THROUGH THE AREA OVERNIGHT SUNDAY. THIS FRONT
IS IN RESPONSE TO AN UPPER LEVEL TROUGH MOVING THROUGH THE PLAINS.
THE WEATHER FOR THANKSGIVING SHOULD BE PRETTY SEASONAL WITH HIGHS
IN THE 60S AND LOWS IN THE 30S/40S.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 55 78 45 64 40 / 60 0 - - -
AUSTIN BERGSTROM INTL AIRPORT 54 77 43 64 37 / 70 0 - - -
NEW BRAUNFELS MUNI AIRPORT 55 79 45 66 40 / 60 0 - - -
BURNET MUNI AIRPORT 52 75 42 62 38 / 50 0 - - -
DEL RIO INTL AIRPORT 50 78 46 65 38 / 20 0 - - -
GEORGETOWN MUNI AIRPORT 54 75 43 62 38 / 60 0 - - -
HONDO MUNI AIRPORT 49 77 42 65 37 / 50 0 - - -
SAN MARCOS MUNI AIRPORT 53 78 44 65 39 / 70 0 - - -
LA GRANGE - FAYETTE REGIONAL 57 78 46 64 40 / 90 0 - - -
SAN ANTONIO INTL AIRPORT 54 78 46 66 41 / 50 0 - - -
STINSON MUNI AIRPORT 54 79 46 66 41 / 60 0 - - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...24
SYNOPTIC/GRIDS...17
PUBLIC SERVICE/DATA COLLECTION...00
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1223 PM CST SAT NOV 22 2014
.UPDATE...
PLEASE SEE THE 18Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ONGOING ACROSS
MUCH OF SOUTH CENTRAL TEXAS EARLY THIS AFTERNOON. THE MOST
CONCENTRATED ACTIVITY WILL BE ALONG AND EAST OF I-35 AND WE/LL
CONTINUE TO MENTION VCTS AND TEMPO TSRA THROUGH THE EARLY EVENING
HOURS. FARTHER WEST AT KDRT...THE BETTER CHANCE FOR TSRA WILL
LIKELY ARRIVE LATE AFTERNOON/EARLY EVENING. SHOWERS AND STORMS MAY
PERSIST ALONG THE I-35 CORRIDOR UNTIL MIDNIGHT...THEN CLEAR AS A
PACIFIC COLD FRONT MOVES THROUGH.
&&
.PREV DISCUSSION... /ISSUED 1052 AM CST SAT NOV 22 2014/
UPDATE...
A SLIGHT RISK OF STRONG TO SEVERE WEATHER CONTINUES ACROSS ALL OF
SOUTH CENTRAL TEXAS FOR THE REST OF TODAY INTO THE EVENING HOURS.
A POTENT UPPER LEVEL STORM SYSTEM LOCATED ACROSS NORTHEAST MEXICO
IS FORECAST TO PUSH EAST AND OVER CENTRAL TEXAS THIS AFTERNOON AND EVENING.
BEST LIFT/UPPER DYNAMIC IS TO THE SOUTHEAST OF THE SHEAR AXIS AND
ABOUT TO CROSS THE SERRANIAS DEL BURRIO MOUNTAINS(NORTHEAST
MEXICO). THIS AREA OF BEST UPPER FORCING WILL MOVE ACROSS THE RIO
GRANDE WITHIN THE NEXT FEW HOURS. LATEST SATELLITE IMAGES ARE
SHOWING SOME BREAKS IN THE CLOUDS OVER THE SOUTHWESTERN COUNTIES AND
THIS COULD ENHANCE STORMS DEVELOPMENT AND SEVERITY. FOR THE
EASTERN PART OF SOUTH CENTRAL TEXAS...CLOUDS ARE EXPECTED TO REMAIN
WITH NO BREAKS ANTICIPATED. THE MAIN WEATHER THREAT FOR ALL OF
SOUTH CENTRAL TEXAS TODAY....STILL LARGE HAIL AND DAMIGING GUST WINDS.
CAN`T RULE OUT AND ISOLATED TORNADO OR TWO MAINLY ACROSS THE
SOUTHWEST AND FAR SOUTHEASTERN COUNTIES. HOWEVER...LATEST HIRES MODELS
AND AREA FORECAST SOUNDINGS ARE INDICATING PWATS OF 1.37 TO 1.48
INCHES. THESE NUMBERS ARE ABOVE THE 2 STANDARD DEVIATIONS FOR THIS
TIME OF THE YEAR. THEREFORE...THE POTENTIAL FOR HEAVY RAIN IS
LIKELY OVER SOME AREAS MAINLY ALONG AND EAST OF A MOUNTAIN HOME TO
CASTROVILLE TO CAMPBELLTON LINE. AS OF NOW...ISOLATED RAIN RATES
OF 2 TO 4 INCHES PER HOURS ARE BEING DETECTED BY EWX RADAR OVER
GILLESPIE AND BLANCO COUNTIES. THIS TREND WILL CONTINUE THROUGH
THE AFTERNOON HOURS AS THE UPPER LEVEL STORM SYSTEM PUSHES TO THE
EAST. EXPECT LOCALIZED FLOODING ACROSS AREA
ROADS/HIGHWAYS/UNDERPASSES AND LOW LYING AND POOR DRAINAGE AREAS.
PREV DISCUSSION... /ISSUED 658 AM CST SAT NOV 22 2014/
UPDATE...
THE KDRT UPPER AIR SOUNDING JUST CAME IN AND IS SHOWING
SUBSTANTIAL MID-LEVEL LAPSE RATES ABOVE A LIFTING CAP. THIS CAP
SHOULD COMPLETELY ERODE SHORTLY AS LIFT CONTINUES TO OVERSPREAD
THE AREA. THE 700-500MB LAPSE RATES ON THE SOUNDING ARE PUSHING 9
C/KM. THE 500 TEMPERATURE COOLED FROM -12C TO -17C IN JUST 12
HOURS. WE ARE GETTING MORE CONCERNED WITH THE SEVERE HAIL
POTENTIAL FROM ANY STORMS WHICH ARE ABLE TO BECOME ROOTED AND
SUSTAINED. ANOTHER CONCERNING CHANGE IS REDEVELOPMENT SHOWING UP
ON THE HRRR. THE HRRR IS OUT NOW TO 1Z AND IS SHOWING
REDEVELOPMENT OF WHAT IS MOST LIKELY TO BE STRONG TO SEVERE
THUNDERSTORMS ALONG THE I-35 CORRIDOR BY 23-00Z. THIS WAS SHOWN
THE PAST SEVERAL DAYS FROM THE NAM...BUT NOW THAT THERE IS SUPPORT
FROM THE HRRR THERE MAY BE SOMETHING TO IT. UPDATED THE GRIDS TO
INCREASE POPS AFTER 00Z FOR AREAS NEAR THE I-35 CORRIDOR. ANOTHER
ASPECT TO THIS IS IF WE GET ANOTHER ROUND OF STORMS...FORECASTED
RAIN TOTALS WILL INCREASE AS WELL. UPDATED THE HWO TO MENTION
ISOLATED 5 INCH TOTALS AND LOCALIZED FLASH FLOODING.
HAMPSHIRE
PREV DISCUSSION... /ISSUED 529 AM CST SAT NOV 22 2014/
AVIATION DISCUSSION...FOR 12Z TAF PACKAGE...
SCATTERED TO POTENTIALLY WIDESPREAD THUNDERSTORMS WILL BE POSSIBLE
FOR MAINLY THE I35 CORRIDOR TERMINALS THROUGHOUT MUCH OF THE TAF
PERIOD. SHORT TERM MODELS SUGGEST THAT STORM DEVELOPMENT WILL
OCCUR LATE MORNING IN THE VICINITY OF ALL TERMINALS BUT THE
MAJORITY OF THE DEVELOPMENT SHOULD BE ABOUT 50 MILES WEST OF THE
I35 CORRIDOR AND EAST.
BEGINNING 18Z AND LASTING THROUGH 03Z...POTENTIALLY SEVERE
THUNDERSTORMS WILL IMPACT TERMINALS OFF AND ON. INCLUDED +TSRA
WITH IFR VIS TO ENCOMPASS THE MAIN IMPACTS TO THE TERMINALS. CIGS
SHOULD REMAIN AT MVFR LEVELS DURING THE DAY BUT MAY DIP TO IFR
DURING THE MORE SIGNIFICANT STORMS. EXPECT THESE IMPACTS TO EXIT
QUICKLY FROM THE AREA AFTER 03Z. THEN VFR SHOULD PREVAIL DURING
THE REMAINDER OF THE PERIOD.
NOTE FOR KDRT...MODELS SUGGEST A SECOND ROUND OF TSRA TO DEVELOP
IN THE VICINITY NEAR 00Z. THIS IS A RECENT BUT CONSISTENT
DEVELOPMENT IN THE MODELS SO INCLUDED PROB30 MENTION TO ACCOUNT
FOR THIS.
PREV DISCUSSION... /ISSUED 342 AM CST SAT NOV 22 2014/
SHORT TERM (TODAY THROUGH SUNDAY)...
LIGHT SHOWER ACTIVITY REMAINS SCATTERED AROUND THE AREA IN
RESPONSE TO CONTINUED WEAK LIFT ASSOCIATED WITH THE LOW-LEVEL JET.
THE JET IS STRONGEST ACROSS THE CENTRAL AND WESTERN ZONES AND THIS
IS WHERE THE HIGHEST CONCENTRATION OF ACTIVITY IS LOCATED. THE
POTENT UPPER LEVEL LOW IS CURRENTLY LOCATED OVER NORTHERN MEXICO
AND IT CONTINUES TO MOVE EAST. THE LARGE SCALE FORCING FOR ASCENT
CAN EASILY BE SEEN ON IR/WV SATELLITE IMAGERY AT THE PRESENT TIME.
THE FORCING IS SHOWN BY THE INCREASING MID-HIGH LEVEL CLOUDS THAT
ARE OVERSPREADING WEST TEXAS. THE MAIN UPPER FORCING SHOULD ARRIVE
TO SOUTH CENTRAL TEXAS LATER THIS MORNING AND CONTINUE THROUGH THE
AFTERNOON AND EVENING HOURS. UNTIL THE MAIN UPPER FOCUS FOR LIFT
ARRIVES...WE SHOULD ONLY CONTINUE TO SEE THIS ISOLATED TO
SCATTERED SHOWER ACTIVITY WITH PERHAPS AN ISOLATED THUNDERSTORM.
THUNDERSTORMS WILL MOST LIKELY BEGIN TO INCREASE IN COVERAGE IN
THE MID TO LATE MORNING HOURS AS THE UPPER LIFT ARRIVES. INITIALLY
THERE WILL BE ABOUT 1500 J/KG OF CAPE ACROSS THE WESTERN HALF OF
THE CWA WITH 30-35 KNOTS OF 0-6 KM SHEAR. CAPE VALUES WILL DROP
OFF TO 1000 J/KG OR LESS ACROSS THE EASTERN ZONES. THE INITIAL
DEVELOPMENT OF STORMS COULD LEAD TO WEAK SUPERCELLS IN THE WESTERN
HALF OF THE CWA IN THE AREA OF BEST INSTABILITY. HOWEVER...ONCE
ACTIVITY BECOMES MORE WIDESPREAD THIS AFTERNOON...THERE MAY END UP
BEING TOO MUCH ACTIVITY TO REALIZE THE PEAK CAPE VALUES. HIGH-RES
GUIDANCE IS CONSISTENTLY SHOWING A LARGE AREA OF PRECIP OVER THE
CWA THAT MOVES FROM WEST TO EAST AND OUT OF THE CWA BY 03Z. THE
SHERB PARAMETER WHICH IS DECENT IN PICKING UP SEVERE POTENTIAL FOR
THESE LOW CAPE/HIGH SHEAR ENVIRONMENTS /EASTERN ZONES/ IS LESS
THAN WHAT WAS FORECASTED YESTERDAY...BUT IS STILL NEAR THE
THRESHOLD TO SUPPORT THE NOTION FOR SOME POSSIBLE SEVERE WIND
GUSTS OUT OF ANY LINE SEGMENTS WHICH FORM WITHIN THE LARGE MASS OF
THUNDERSTORMS. CURRENT THINKING IS THAT INITIALLY...SOME
THUNDERSTORMS COULD PRODUCE MARGINALLY SEVERE HAIL MAINLY ACROSS
THE WESTERN HALF OF THE AREA DURING THE LATE MORNING AND INTO THE
EARLY AFTERNOON. THEN...SOME MARGINALLY SEVERE WIND GUSTS WOULD
BE THE MAIN MODE OF SEVERE CONVECTION FROM ANY POSSIBLE LINE
SEGMENTS IN THE EASTERN ZONES. THE RISK FOR TORNADOES IS NON-
ZERO...BUT LOW WITH THE BEST POTENTIAL BEING IN THE SOUTHEAST
ZONES...WHERE THE BEST LOW-LEVEL SHEAR IS LOCATED.
PW VALUES WILL RISE UP TO 1.5 INCHES ACROSS THE EASTERN AND
NORTHERN ZONES. THIS IS ABOUT 2 STANDARD DEVIATIONS ABOVE NORMAL
FOR THIS TIME OF THE YEAR. THEREFORE...WE COULD SEE LOCALLY HEAVY
RAINFALL...MAINLY ACROSS THESE MENTIONED AREAS. WPC DAY 1 QPF
VALUES RANGE FROM NEAR 1/4 OF AN INCH NEAR THE RIO GRANDE TO NEAR
2 INCHES IN OUR NORTHERN ZONES. THIS SEEMS REASONABLE...BUT SOME
ISOLATED LOCATIONS COULD RECEIVE UP TO 4 INCHES OF RAIN.
ALL ACTIVITY IS EXPECTED TO BE EAST OF THE AREA BY 3Z OR 9 PM.
WEST WINDS AT THE SURFACE WILL CONTINUE ON SUNDAY GIVING US A
DOWNSLOPE COMPONENT FROM WEST TO EAST. THIS USUALLY LEADS TO WARM
TEMPERATURES AND HIGHS SUNDAY WILL REACH THE MID 70S TO NEAR 80
DEGREES.
LONG TERM (SUNDAY NIGHT THROUGH FRIDAY)...
THE WEATHER IN THE EXTENDED IS EXPECTED TO BE FAIRLY QUIET. A WEAK
FRONT WILL MOVE THROUGH THE AREA OVERNIGHT SUNDAY. THIS FRONT IS IN
RESPONSE TO AN UPPER LEVEL TROUGH MOVING THROUGH THE PLAINS. THIS
FRONT WILL BE DRY AS MOISTURE WILL REMAIN SHUNTED OFF TO THE EAST.
THE REST OF THE WEEK WILL REMAIN DRY AND THE NEXT FRONT SHOULD
MOVE INTO THE AREA AROUND FRIDAY. THE WEATHER FOR THANKSGIVING
SHOULD BE PRETTY SEASONAL WITH HIGHS IN THE 60S AND LOWS IN THE
30S/40S.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 69 55 78 45 64 / 100 60 0 - -
AUSTIN BERGSTROM INTL AIRPORT 71 54 77 43 64 / 100 70 0 - -
NEW BRAUNFELS MUNI AIRPORT 75 55 79 45 66 / 90 60 0 - -
BURNET MUNI AIRPORT 67 52 75 42 62 / 100 50 0 - -
DEL RIO INTL AIRPORT 73 50 78 46 65 / 40 20 0 - -
GEORGETOWN MUNI AIRPORT 68 54 75 43 62 / 100 60 0 - -
HONDO MUNI AIRPORT 73 49 77 42 65 / 70 50 0 - -
SAN MARCOS MUNI AIRPORT 70 53 78 44 65 / 90 70 0 - -
LA GRANGE - FAYETTE REGIONAL 73 57 78 46 64 / 90 90 0 - -
SAN ANTONIO INTL AIRPORT 75 54 78 46 66 / 80 60 0 - -
STINSON MUNI AIRPORT 76 54 79 46 66 / 80 60 0 - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...24
SYNOPTIC/GRIDS...17
PUBLIC SERVICE/DATA COLLECTION...00
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1120 AM CST SAT NOV 22 2014
.AVIATION...
AN UPPER LEVEL STORM SYSTEM WILL CONTINUE TO AFFECT THE REGION
TODAY. ALTHOUGH SCATTERED THUNDERSTORMS CURRENTLY SOUTHEAST OF
KLBB WILL CONTINUE TO MOVE TOWARDS KCDS...THIS ACTIVITY IS
EXPECTED TO TAKE A MORE EASTERLY MOVEMENT AND MAY NOT AFFECT THE
KCDS TERMINAL. WIDESPREAD LOW CIGS AND VISBYS ARE NOT EXPECTED TO
RETURN BUT THERE MAY BE A BRIEF REDUCTION IN FLIGHT CONDITIONS
THIS EVENING BEFORE WINDS TURN TO THE WEST-NORTHWEST. STRONG WINDS
ON THE BACK SIDE OF THIS SYSTEM WILL BEGIN TO INCREASE SURFACE
WINDS BY LATE SUNDAY MORNING AT BOTH TAF SITES. GIVEN THE TIME OF
YEAR...IT IS UNCLEAR ON WHETHER THERE WILL BE ANY VISBY
RESTRICTIONS DUE TO BLDU.
&&
.PREV DISCUSSION... /ISSUED 906 AM CST SAT NOV 22 2014/
UPDATE...
WATER VAPOR IMAGERY SHOWED AN AREA OF LIFT IN AN UPPER LEVEL
DIFFLUENT AREA MOVING OUT OF EXTREME SOUTHEASTERN NEW MEXICO INTO
THE SOUTHWESTERN SOUTH PLAINS. THIS LIFT WAS RESULTING IN SOME
THUNDERSTORM ACTIVITY WHERE SHORT TERM MODELS CURRENTLY SHOW NO
DEVELOPMENT. POPS HAVE BEEN RAISED FOR THE REMAINDER OF THE
MORNING IN ANTICIPATION FOR THIS ACTIVITY TO AFFECT THE SOUTHERN
SOUTH PLAINS. THIS LIFT IS THEN EXPECTED TO QUICKLY MOVE EAST THIS
AFTERNOON.
PREV DISCUSSION... /ISSUED 524 AM CST SAT NOV 22 2014/
AVIATION...
VLIFR FOG AND LIFR CLOUD DECKS HAVE DEVELOPED AT KCDS THIS
MORNING...WITH KLBB VIS DROPPING BELOW 10 SM AND FEW DECKS BELOW
2000 FT AGL. WILL EXPECT KLBB TO FURTHER DETERIORATE LATER THIS
MORNING TO MVFR FOG AND IFR DECKS. CONDITIONS WILL IMPROVE TO VFR
CATEGORY BY MID-MORNING. LIGHT AND VARIABLE WINDS WILL VEER TO THE
WEST SOUTHWEST THIS AFTN AND BECOME SLIGHTLY BREEZY TOWARDS THE
END OF TAF PERIOD.
PREV DISCUSSION... /ISSUED 214 AM CST SAT NOV 22 2014/
SHORT TERM...
MAIN FOCUS FOR THE SHORT TERM PERIOD CONTINUES TO BE THE UA LOW
DIGGING ESE ACROSS NWRN OLD MEXICO EARLY THIS MORNING...WHICH WILL
AID TO INCREASE PRECIP CHANCES LATER THIS MORNING.
AN AREA OF STRATUS AND FOGGY CONDITIONS ONCE AGAIN DEVELOPED ACROSS
ERN TEXAS AND OKLAHOMA PER 08Z METARS...THUS COINCIDING WITH THE
BEST SFC MOISTURE /DEWPOINTS IN THE 50S AND 60S/. LOW CLOUDS AND FOG
HAVE IMPACTED THE FAR SERN TX PANHANDLE...WHICH IS NOT SURPRISING
GIVEN A LOW TEMP-DEWPOINT SPREAD. THE HRRR SOLUTION HANDLED THE
EVOLUTION OF THE LOW CLOUDS AND FOG QUITE WELL YESTERDAY...AND SINCE
IT SHOWS A CONTINUAL WESTWARD DEVELOPMENT FOR THE NEXT SEVERAL HOURS
UNTIL MID-MORNING WHERE THEREAFTER CONDITIONS WILL IMPROVE...THIS
FORECAST PACKAGE WILL REFLECT THAT PROGRESSION.
AS PREVIOUSLY STATED...THE BEST MOISTURE AXIS WAS NOTED EAST OF THE
FA AND WITH THE AID OF A BIT OF UL SUPPORT FROM THE UA LOW ACROSS
NWRN OLD MEXICO...RADAR ANALYSIS DEPICTED SCATTERED SHOWERS
DEVELOPING ACROSS THE LOW ROLLING PLAINS AND BIG COUNTRY AREAS. WITH
THE LLJ PROGGED TO INCREASE TO 30-40 KTS ACROSS THE ROLLING PLAINS
WITHIN THE NEXT FEW HOURS COUPLED WITH INCREASING LARGE SCALE ASCENT
AND A MOISTENING ATMOSPHERE /PWATS INCREASING TO AOA 1.10
INCHES/...CHANCES FOR ADDITIONAL SHOWERS AND THUNDERSTORMS WILL BE
ON THE INCREASE PARTICULARLY ACROSS THE ROLLING PLAINS. SOME OF THIS
ACTIVITY COULD POSE A THREAT FOR MODERATE TO HEAVY RAINFALL AS
PWATS INCREASE TO ABOVE 1.00 INCH THROUGHOUT THIS MORNING.
FURTHERMORE...MID-LEVEL CAPE VALUES OF 1000-1500 J/KG COMBINED WITH
0-6 KM BULK SHEAR VALUES AOA 40 KTS...SUGGEST SOME OF THE ACTIVITY
COULD APPROACH STRONG LEVELS WITH HAIL BEING THE PRIMARY THREAT
/PARTICULARLY ACROSS THE LOW ROLLING PLAINS/. STORMS WILL LINGER INTO
EARLY AFTN WHERE THEREAFTER...MODEL SOUNDINGS EXHIBITING A DRYING
PROFILE AND THE UA LOW MOVING EAST TOWARDS SE TX WILL RESULT IN
PRECIP EXITING THE REGION. BY LATE THIS EVENING/EARLY TONIGHT...A
DEEPENING SFC LOW PROGRESSING EAST ACROSS THE CENTRAL PLAINS WILL
PROMOTE W-SW SFC WINDS TO BECOME SLIGHTLY BREEZY BY THE END OF THE
SHORT TERM PERIOD.
TEMPS WILL BE A FEW DEGREES ABOVE NORM TODAY /MIDDLE TO UPPER 60S/
FOLLOWED BY A RELATIVELY MILD NIGHT /UPPER 30S TO MIDDLE 40S/.
LONG TERM...
NO SIGNIFICANT CHANGES TO THE FCST THIS MORNING. MODELS REMAIN
CONSISTENT IN KEEPING THE SRN HIGH PLAINS UNDERNEATH NORTHWESTERLY
FLOW ALOFT. A COUPLE OF SHORT WAVE TROUGHS MOVING THROUGH THIS
UPPER FLOW WILL PRODUCE A COUPLE PERIODS OF BREEZY TO WINDY
CONDITIONS SUNDAY AND MONDAY...THE STRONGEST WINDS COMING SUNDAY
ACROSS THE SWRN HALF OF THE FCST AREA...POSSIBLY MEETING ADVISORY
CRITERIA FOR A PERIOD OF TIME DURING THE AFTERNOON HOURS. TEMPS
NEAR OR JUST BELOW SEASONAL NORMS WITH THE WARMEST DAYS LIKELY
BEING WEDNESDAY AND THURSDAY. STILL SOME MODEL SOLUTIONS SHOWING
A BRIEF INCURSION OF COLD AIR TOWARD FRIDAY...BUT CERTAINLY NOW
CONSENSUS IN THAT REGARD ATTM.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 67 38 53 23 49 / 10 0 10 10 0
TULIA 67 40 53 25 52 / 20 10 10 10 0
PLAINVIEW 67 41 56 26 53 / 20 10 10 10 0
LEVELLAND 66 42 60 27 53 / 20 0 0 10 0
LUBBOCK 66 43 61 27 54 / 50 10 0 10 0
DENVER CITY 65 41 62 28 53 / 30 0 0 10 0
BROWNFIELD 65 42 61 28 54 / 50 10 0 10 0
CHILDRESS 67 45 62 32 56 / 60 10 0 10 0
SPUR 67 45 63 35 58 / 60 10 0 10 0
ASPERMONT 69 46 66 34 58 / 80 10 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
01
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1052 AM CST SAT NOV 22 2014
.UPDATE...
A SLIGHT RISK OF STRONG TO SEVERE WEATHER CONTINUES ACROSS ALL OF
SOUTH CENTRAL TEXAS FOR THE REST OF TODAY INTO THE EVENING HOURS.
A POTENT UPPER LEVEL STORM SYSTEM LOCATED ACROSS NORTHEAST MEXICO
IS FORECAST TO PUSH EAST AND OVER CENTRAL TEXAS THIS AFTERNOON AND EVENING.
BEST LIFT/UPPER DYNAMIC IS TO THE SOUTHEAST OF THE SHEAR AXIS AND
ABOUT TO CROSS THE SERRANIAS DEL BURRIO MOUNTAINS(NORTHEAST
MEXICO). THIS AREA OF BEST UPPER FORCING WILL MOVE ACROSS THE RIO
GRANDE WITHIN THE NEXT FEW HOURS. LATEST SATELLITE IMAGES ARE
SHOWING SOME BREAKS IN THE CLOUDS OVER THE SOUTHWESTERN COUNTIES AND
THIS COULD ENHANCE STORMS DEVELOPMENT AND SEVERITY. FOR THE
EASTERN PART OF SOUTH CENTRAL TEXAS...CLOUDS ARE EXPECTED TO REMAIN
WITH NO BREAKS ANTICIPATED. THE MAIN WEATHER THREAT FOR ALL OF
SOUTH CENTRAL TEXAS TODAY....STILL LARGE HAIL AND DAMIGING GUST WINDS.
CAN`T RULE OUT AND ISOLATED TORNADO OR TWO MAINLY ACROSS THE
SOUTHWEST AND FAR SOUTHEASTERN COUNTIES. HOWEVER...LATEST HIRES MODELS
AND AREA FORECAST SOUNDINGS ARE INDICATING PWATS OF 1.37 TO 1.48
INCHES. THESE NUMBERS ARE ABOVE THE 2 STANDARD DEVIATIONS FOR THIS
TIME OF THE YEAR. THEREFORE...THE POTENTIAL FOR HEAVY RAIN IS
LIKELY OVER SOME AREAS MAINLY ALONG AND EAST OF A MOUNTAIN HOME TO
CASTROVILLE TO CAMPBELLTON LINE. AS OF NOW...ISOLATED RAIN RATES
OF 2 TO 4 INCHES PER HOURS ARE BEING DETECTED BY EWX RADAR OVER
GILLESPIE AND BLANCO COUNTIES. THIS TREND WILL CONTINUE THROUGH
THE AFTERNOON HOURS AS THE UPPER LEVEL STORM SYSTEM PUSHES TO THE
EAST. EXPECT LOCALIZED FLOODING ACROSS AREA
ROADS/HIGHWAYS/UNDERPASSES AND LOW LYING AND POOR DRAINAGE AREAS.
&&
.PREV DISCUSSION... /ISSUED 658 AM CST SAT NOV 22 2014/
UPDATE...
THE KDRT UPPER AIR SOUNDING JUST CAME IN AND IS SHOWING
SUBSTANTIAL MID-LEVEL LAPSE RATES ABOVE A LIFTING CAP. THIS CAP
SHOULD COMPLETELY ERODE SHORTLY AS LIFT CONTINUES TO OVERSPREAD
THE AREA. THE 700-500MB LAPSE RATES ON THE SOUNDING ARE PUSHING 9
C/KM. THE 500 TEMPERATURE COOLED FROM -12C TO -17C IN JUST 12
HOURS. WE ARE GETTING MORE CONCERNED WITH THE SEVERE HAIL
POTENTIAL FROM ANY STORMS WHICH ARE ABLE TO BECOME ROOTED AND
SUSTAINED. ANOTHER CONCERNING CHANGE IS REDEVELOPMENT SHOWING UP
ON THE HRRR. THE HRRR IS OUT NOW TO 1Z AND IS SHOWING
REDEVELOPMENT OF WHAT IS MOST LIKELY TO BE STRONG TO SEVERE
THUNDERSTORMS ALONG THE I-35 CORRIDOR BY 23-00Z. THIS WAS SHOWN
THE PAST SEVERAL DAYS FROM THE NAM...BUT NOW THAT THERE IS SUPPORT
FROM THE HRRR THERE MAY BE SOMETHING TO IT. UPDATED THE GRIDS TO
INCREASE POPS AFTER 00Z FOR AREAS NEAR THE I-35 CORRIDOR. ANOTHER
ASPECT TO THIS IS IF WE GET ANOTHER ROUND OF STORMS...FORECASTED
RAIN TOTALS WILL INCREASE AS WELL. UPDATED THE HWO TO MENTION
ISOLATED 5 INCH TOTALS AND LOCALIZED FLASH FLOODING.
HAMPSHIRE
PREV DISCUSSION... /ISSUED 529 AM CST SAT NOV 22 2014/
AVIATION DISCUSSION...FOR 12Z TAF PACKAGE...
SCATTERED TO POTENTIALLY WIDESPREAD THUNDERSTORMS WILL BE POSSIBLE
FOR MAINLY THE I35 CORRIDOR TERMINALS THROUGHOUT MUCH OF THE TAF
PERIOD. SHORT TERM MODELS SUGGEST THAT STORM DEVELOPMENT WILL
OCCUR LATE MORNING IN THE VICINITY OF ALL TERMINALS BUT THE
MAJORITY OF THE DEVELOPMENT SHOULD BE ABOUT 50 MILES WEST OF THE
I35 CORRIDOR AND EAST.
BEGINNING 18Z AND LASTING THROUGH 03Z...POTENTIALLY SEVERE
THUNDERSTORMS WILL IMPACT TERMINALS OFF AND ON. INCLUDED +TSRA
WITH IFR VIS TO ENCOMPASS THE MAIN IMPACTS TO THE TERMINALS. CIGS
SHOULD REMAIN AT MVFR LEVELS DURING THE DAY BUT MAY DIP TO IFR
DURING THE MORE SIGNIFICANT STORMS. EXPECT THESE IMPACTS TO EXIT
QUICKLY FROM THE AREA AFTER 03Z. THEN VFR SHOULD PREVAIL DURING
THE REMAINDER OF THE PERIOD.
NOTE FOR KDRT...MODELS SUGGEST A SECOND ROUND OF TSRA TO DEVELOP
IN THE VICINITY NEAR 00Z. THIS IS A RECENT BUT CONSISTENT
DEVELOPMENT IN THE MODELS SO INCLUDED PROB30 MENTION TO ACCOUNT
FOR THIS.
PREV DISCUSSION... /ISSUED 342 AM CST SAT NOV 22 2014/
SHORT TERM (TODAY THROUGH SUNDAY)...
LIGHT SHOWER ACTIVITY REMAINS SCATTERED AROUND THE AREA IN
RESPONSE TO CONTINUED WEAK LIFT ASSOCIATED WITH THE LOW-LEVEL JET.
THE JET IS STRONGEST ACROSS THE CENTRAL AND WESTERN ZONES AND THIS
IS WHERE THE HIGHEST CONCENTRATION OF ACTIVITY IS LOCATED. THE
POTENT UPPER LEVEL LOW IS CURRENTLY LOCATED OVER NORTHERN MEXICO
AND IT CONTINUES TO MOVE EAST. THE LARGE SCALE FORCING FOR ASCENT
CAN EASILY BE SEEN ON IR/WV SATELLITE IMAGERY AT THE PRESENT TIME.
THE FORCING IS SHOWN BY THE INCREASING MID-HIGH LEVEL CLOUDS THAT
ARE OVERSPREADING WEST TEXAS. THE MAIN UPPER FORCING SHOULD ARRIVE
TO SOUTH CENTRAL TEXAS LATER THIS MORNING AND CONTINUE THROUGH THE
AFTERNOON AND EVENING HOURS. UNTIL THE MAIN UPPER FOCUS FOR LIFT
ARRIVES...WE SHOULD ONLY CONTINUE TO SEE THIS ISOLATED TO
SCATTERED SHOWER ACTIVITY WITH PERHAPS AN ISOLATED THUNDERSTORM.
THUNDERSTORMS WILL MOST LIKELY BEGIN TO INCREASE IN COVERAGE IN
THE MID TO LATE MORNING HOURS AS THE UPPER LIFT ARRIVES. INITIALLY
THERE WILL BE ABOUT 1500 J/KG OF CAPE ACROSS THE WESTERN HALF OF
THE CWA WITH 30-35 KNOTS OF 0-6 KM SHEAR. CAPE VALUES WILL DROP
OFF TO 1000 J/KG OR LESS ACROSS THE EASTERN ZONES. THE INITIAL
DEVELOPMENT OF STORMS COULD LEAD TO WEAK SUPERCELLS IN THE WESTERN
HALF OF THE CWA IN THE AREA OF BEST INSTABILITY. HOWEVER...ONCE
ACTIVITY BECOMES MORE WIDESPREAD THIS AFTERNOON...THERE MAY END UP
BEING TOO MUCH ACTIVITY TO REALIZE THE PEAK CAPE VALUES. HIGH-RES
GUIDANCE IS CONSISTENTLY SHOWING A LARGE AREA OF PRECIP OVER THE
CWA THAT MOVES FROM WEST TO EAST AND OUT OF THE CWA BY 03Z. THE
SHERB PARAMETER WHICH IS DECENT IN PICKING UP SEVERE POTENTIAL FOR
THESE LOW CAPE/HIGH SHEAR ENVIRONMENTS /EASTERN ZONES/ IS LESS
THAN WHAT WAS FORECASTED YESTERDAY...BUT IS STILL NEAR THE
THRESHOLD TO SUPPORT THE NOTION FOR SOME POSSIBLE SEVERE WIND
GUSTS OUT OF ANY LINE SEGMENTS WHICH FORM WITHIN THE LARGE MASS OF
THUNDERSTORMS. CURRENT THINKING IS THAT INITIALLY...SOME
THUNDERSTORMS COULD PRODUCE MARGINALLY SEVERE HAIL MAINLY ACROSS
THE WESTERN HALF OF THE AREA DURING THE LATE MORNING AND INTO THE
EARLY AFTERNOON. THEN...SOME MARGINALLY SEVERE WIND GUSTS WOULD
BE THE MAIN MODE OF SEVERE CONVECTION FROM ANY POSSIBLE LINE
SEGMENTS IN THE EASTERN ZONES. THE RISK FOR TORNADOES IS NON-
ZERO...BUT LOW WITH THE BEST POTENTIAL BEING IN THE SOUTHEAST
ZONES...WHERE THE BEST LOW-LEVEL SHEAR IS LOCATED.
PW VALUES WILL RISE UP TO 1.5 INCHES ACROSS THE EASTERN AND
NORTHERN ZONES. THIS IS ABOUT 2 STANDARD DEVIATIONS ABOVE NORMAL
FOR THIS TIME OF THE YEAR. THEREFORE...WE COULD SEE LOCALLY HEAVY
RAINFALL...MAINLY ACROSS THESE MENTIONED AREAS. WPC DAY 1 QPF
VALUES RANGE FROM NEAR 1/4 OF AN INCH NEAR THE RIO GRANDE TO NEAR
2 INCHES IN OUR NORTHERN ZONES. THIS SEEMS REASONABLE...BUT SOME
ISOLATED LOCATIONS COULD RECEIVE UP TO 4 INCHES OF RAIN.
ALL ACTIVITY IS EXPECTED TO BE EAST OF THE AREA BY 3Z OR 9 PM.
WEST WINDS AT THE SURFACE WILL CONTINUE ON SUNDAY GIVING US A
DOWNSLOPE COMPONENT FROM WEST TO EAST. THIS USUALLY LEADS TO WARM
TEMPERATURES AND HIGHS SUNDAY WILL REACH THE MID 70S TO NEAR 80
DEGREES.
LONG TERM (SUNDAY NIGHT THROUGH FRIDAY)...
THE WEATHER IN THE EXTENDED IS EXPECTED TO BE FAIRLY QUIET. A WEAK
FRONT WILL MOVE THROUGH THE AREA OVERNIGHT SUNDAY. THIS FRONT IS IN
RESPONSE TO AN UPPER LEVEL TROUGH MOVING THROUGH THE PLAINS. THIS
FRONT WILL BE DRY AS MOISTURE WILL REMAIN SHUNTED OFF TO THE EAST.
THE REST OF THE WEEK WILL REMAIN DRY AND THE NEXT FRONT SHOULD
MOVE INTO THE AREA AROUND FRIDAY. THE WEATHER FOR THANKSGIVING
SHOULD BE PRETTY SEASONAL WITH HIGHS IN THE 60S AND LOWS IN THE
30S/40S.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 69 56 80 46 64 / 100 60 0 - -
AUSTIN BERGSTROM INTL AIRPORT 71 56 80 46 64 / 100 70 0 - -
NEW BRAUNFELS MUNI AIRPORT 75 56 81 46 65 / 90 60 0 - -
BURNET MUNI AIRPORT 67 53 77 42 62 / 100 50 0 - -
DEL RIO INTL AIRPORT 73 51 80 46 65 / 40 20 0 - -
GEORGETOWN MUNI AIRPORT 68 55 78 44 62 / 100 60 0 - -
HONDO MUNI AIRPORT 73 53 78 45 64 / 70 50 0 - -
SAN MARCOS MUNI AIRPORT 70 56 80 45 64 / 90 70 0 - -
LA GRANGE - FAYETTE REGIONAL 73 57 79 46 64 / 90 90 0 - -
SAN ANTONIO INTL AIRPORT 75 55 80 46 65 / 80 60 0 - -
STINSON MUNI AIRPORT 76 56 81 47 66 / 80 60 0 - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...24
SYNOPTIC/GRIDS...17
PUBLIC SERVICE/DATA COLLECTION...00
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
324 PM CST SAT NOV 22 2014
.SHORT TERM...
TONIGHT...FORECAST CONFIDENCE MEDIUM.
MAIN CONCERN WILL BE ON TIMING OF PRECIP AND HANDLING FOG TRENDS.
MILD AND MOIST FLOW WILL PERSIST ALL NIGHT. ISODROSOTHERM ANALYSIS
SHOWS THE MOIST AXIS POINTING RIGHT INTO SRN WI WITH A GRADUAL
ADVECTION PATTERN NOTED. MID LEVEL ACROSS HERE IS ZONAL WITH THE
MAIN UPPER LOW WELL SOUTH IN TX. LOWS WILL BE ESTABLISHED EARLY
THIS EVENING WITH POSITIVE TEMP ADVECTION LIKELY FOR MUCH OF THE
NIGHT. GUIDANCE HAS BEEN SENDING MIXED SIGNALS ON HOW DENSE FOG
GETS TONIGHT. WINDS INCREASE OFF THE DECK AND THAT MAY LIMIT
THINGS FROM GETTING OUT OF HAND IN A WIDESPREAD FASHION.
NEVERTHELESS EXPECT IT TO REMAIN FOGGY BUT WILL ELECT TO NOT ISSUE
A HEADLINE AT THIS TIME. OVERALL LOOKS CLOUDY...MILD...FOGGY WITH
SOME DRIZZLE AND PERHAPS A FEW SHOWERS. LATEST HRRR BRINGS A BAND
OF SHRA THROUGH HERE IN THE 03-07Z RANGE BUT THEN NOT MUCH AFTER
THAT THROUGH 12Z.
SUNDAY...FORECAST CONFIDENCE MEDIUM.
GRADUAL PROGRESSION AND AMPLIFICATION OF WESTERN TROUGH. THIS
KEEPS SRN WI IN A BROAD SSW UPPER FLOW. SHORTWAVE ACTION IN THIS
FLOW INCREASES ESP AFTER 18Z. WILL HAVE DEFINITE POPS. THERMAL
PROFILE SUPPORTS RAIN CWA WIDE. CLOUDS/RAIN WILL LIMIT TEMPS BUT
STILL EXPECT ENOUGH TEMP ADVECTION TO REACH AT LEAST THE LOW 50S
IN MANY LOCALES.
SUNDAY NIGHT THROUGH TUESDAY...FORECAST CONFIDENCE MEDIUM.
STRONG CYCLOGENESIS IS EXPECTED FROM SW IL TO FAR ERN UPPER MI...AS
A SHORTWAVE TROUGH MOVES NORTH THROUGH THE GREAT LAKES AND A LARGER
SCALE UPPER TROUGH APPROACHES FROM THE PLAINS. A CONSENSUS OF
MODELS DEEPEN THE LOW TO 980 MB BY 12Z MON OVER FAR ERN UPPER MI
AND TAKE IT TO THE ONTARIO AND QUEBEC BORDER BY 00Z TUE. THE UPPER
WAVE AND WARM CONVEYOR BELT WILL BRING PWS OF ONE INCH AND
WIDESPREAD MDT RAINFALL SUN NT. RAINFALL FORECAST FOR SUN AFT
THROUGH THE NIGHT IS AROUND 1 INCH. 850-700 MB FRONTOGENESIS WILL
BE ON THE TRAILING END OF THE SYSTEM FOR MON AND MON NT AS THE
LARGE UPPER TROUGH SLOWLY MOVES ACROSS THE AREA. THUS EXPECT SOME
LIGHT SNOW ACCUM AS THE CHANGE TO SNOW OCCURS FROM WEST TO EAST
MON AM AND THE SNOW CONTINUES MON NT. ANY LINGERING LGT SNOW WILL
COME TO AN END TUE AM WITH POLAR HIGH PRESSURE BUILDING INTO WI
FOR THE AFT AND NIGHT. SFC TEMPS TO DROP THROUGHOUT THE DAY ON
MON ON BRISK WLY WINDS AND COLD ADVECTION. WELL BELOW NORMAL TEMPS
THEN RETURN FOR THE NEW WEEK.
.LONG TERM...WEDNESDAY THROUGH SATURDAY...FORECAST CONFIDENCE
MEDIUM.
A COUPLE SHORTWAVE TROUGHS WILL DIG SEWD FROM CANADA INTO THE
REGION FOR WED-THU AND ESTABLISH NW FLOW ALOFT FOR THE REMAINDER
OF THE WEEK. SFC LOW PRESSURE AND CHANCES OF LIGHT SNOW WILL
ACCOMPANY THE UPPER WAVES BUT THE TIMING IS UNCERTAIN. LIGHT SNOW
ACCUM IS LIKELY HOWEVER. VERY COLD TEMPS WILL CONTINUE DURING THIS
PERIOD.
&&
.AVIATION/00Z TAFS/...MAIN CONCERN WILL BE STRATUS/FOG TRENDS WITHIN
THE MILD AND MOIST REGIME THAT LASTS RIGHT INTO SUNDAY. PLENTY OF
WIND TAKES SHAPE UPSTAIRS WHICH RESULTS IN SOME LLWS CONDITIONS
OVERNIGHT. ATTM BELIEVE THIS WILL KEEP THE FOG FROM GETTING
PERSISTENTLY DENSE. BUT WILL HAVE SOME DENSE FOG POCKETS ACROSS THE
CWA...BUT CONFIDENCE LOW ON WIDESPREAD AT THIS TIME. LIFR CEILINGS
WILL PERSIST INTO SUNDAY AS RAIN BECOMES WIDESPREAD. THIS MAY HELP
TO FURTHER MIX VSBYS A BIT BUT STILL EXPECT IFR VSBYS WITH A FEW
LIFR VSBYS IN ANY DENSE FOG POCKETS.
&&
.MARINE...STILL LOOKING AT POTENTIAL FOR SOME HIGHER WAVES OFFSHORE
FROM SHEBOYGAN TOWARDS OPEN WATERS...SO WILL LET THE SMALL CRAFT GO
TIL THE 00Z END TIME THERE. NEXT CONCERN WILL BE INCREASING WINDS
FOR SUNDAY AND SUNDAY EVENING. APPEARS BORDERLINE SMALL CRAFT ATTM
AS SURFACE LOW MOVES INTO SRN IL BY 00Z. A SSE WIND DEVELOPS BUT
EXPECT WAVES/WINDS TO REMAIN JUST BELOW CRITERIA. MAIN CONCERN WILL
BE ONCE THE LOW STRENGTHENS AND LIFTS NORTH OF THE AREA MONDAY INTO
MONDAY EVENING. RATHER GUSTY WEST WINDS DEVELOP AND BUFKIT SOUNDINGS
SUPPORT SOME GALE CONDITIONS IN THIS REGIME. SO HAVE HOISTED A GALE
WATCH FROM MID MORNING MONDAY THOUGH MIDNIGHT MONDAY NIGHT. HIGHEST
WAVES TOWARDS OPEN WATERS.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...GALE WATCH FROM MONDAY MORNING THROUGH MONDAY EVENING FOR
LMZ643>646.
SMALL CRAFT ADVISORY UNTIL 6 PM CST THIS EVENING FOR LMZ643.
&&
$$
TONIGHT/SUNDAY AND AVIATION/MARINE...COLLAR
SUNDAY NIGHT THROUGH SATURDAY...GEHRING
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
313 PM CST SAT NOV 22 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 313 PM CST SAT NOV 22 2014
CURRENTLY AS OF 21Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A POWERFUL TROUGH OVER THE PACIFIC NORTHWEST...NOTED
BY A 155 KT JET NEAR 300MB ON THE 12Z MEDFORD OREGON RAOB. OTHER
FEATURES OF NOTE WERE AN UPPER LOW OVER THE BIG BEND REGION OF TEXAS
AND AN UPPER RIDGE OVER THE DAKOTAS AND MN. BELOW THE UPPER
RIDGE...WEST TO SOUTHWEST WINDS OF 20-30 KT FROM 925-850MB PER
PROFILER/VWP DATA HAS BEEN ADVECTING WARMER AIR INTO THE REGION.
925MB TEMPS HAVE RISEN FROM -1 TO 2C AT 12Z TO 2-6C AT 21Z.
HOWEVER...TAMDAR SOUNDINGS SHOW MUCH OF THIS WARMING HAS BEEN
STRENGTHENING A STRONG LOW LEVEL INVERSION...TRAPPING MOISTURE
ADVECTING NORTHWARD ON SOUTHERLY WINDS. DEWPOINTS PRESENTLY RANGE IN
THE 30S TO LOW 40S ACROSS THE FORECAST AREA...BUT 40S TO MID 50S
WERE LURKING ACROSS CENTRAL AND SOUTHERN IOWA. THE INCREASED
WARMING AND MOISTURE AT THE SURFACE HAS ALSO ALLOWED THE SNOWPACK TO
BEGIN TO WARM AND MELT...ADDING ADDITIONAL MOISTURE. WE HAVE SEEN
DENSE FOG EARLIER IN THE DAY...BUT DAYTIME MIXING PLUS WARMER AIR
COMING UP FROM THE SOUTH HAS HELPED TO RAISE VISIBILITIES FOR NOW.
FOR TONIGHT...IMPRESSIVE SURFACE TO 925MB WARM AND MOIST AIR
ADVECTION REMAINS PROGGED TO OCCUR ACROSS THE FORECAST AREA...AIDED
BY THE 925MB WINDS INCREASING TO 30-40 KT. 925MB TEMPS AND
DEWPOINTS BY 12Z SUNDAY CLIMB TO 8-10C...WITH MUCH OF THE JUMP
HAPPENING BETWEEN 00-06Z. THESE DEWPOINTS ARE 2-3 STANDARD
DEVIATIONS ABOVE NORMAL. HAD TO DO SOME MAJOR TEMP/DEWPOINT
ADJUSTMENTS TO HANDLE THIS WARM/MOIST AIR ADVECTION...FOLLOWING
MORE OF THE ECMWF/CANADIAN WHICH ARE NOT AFFECTED AS MUCH BY
SNOWPACK LIKE THE NAM IS. WITH ALL OF THIS WARMING AND MOISTURE
COMING ACROSS THE SNOWPACK...ANTICIPATE FAIRLY RAPID MELTING...
THROWING MORE MOISTURE INTO THE BOUNDARY LAYER. GIVEN AN
INVERSION HOLDING IN PLACE BETWEEN 850-900MB THIS EVENING...BELIEVE
WE SHOULD GET MORE FOG TO DEVELOP...POSSIBLY DENSE...SIMILAR TO WHAT
IS GOING ON RIGHT NOW IN SOUTH CENTRAL IA ON I-35 ON THE NOSE OF
THE MOISTURE SURGE. CONSIDERED GOING WITH AN ADVISORY...BUT
AFTERNOON TRENDS HAS REDUCED CONFIDENCE. ADVISORIES ARE STILL
POSSIBLE...THOUGH. OVERNIGHT...ALL THE FOG COULD DISSIPATE AS
THAT INVERSION WEAKENS...AS INDICATED IN RAP/HIRESARW VISIBILITY
FORECASTS. IN FACT...WE SHOULD HAVE THE AIRMASS OVER MISSOURI IN
PLACE WHICH FEATURES NO VISIBILITY RESTRICTION. SINCE THERE STILL
IS SNOWPACK...HAVE KEPT SOME FOG MENTION...BUT WE MAY NOT HAVE
MUCH SNOWPACK EXCEPT IN OUR NORTH BY THE TIME 12Z ROLLS AROUND.
ALONG WITH THE FOG...THE STRONG INCREASE OF LOW LEVEL MOISTURE IS
LIKELY TO LEAD TO AREAS- WIDESPREAD DRIZZLE...ESPECIALLY
OVERNIGHT.
ON SUNDAY...GOOD MODEL CONSENSUS EXISTS FOR DEEP TROUGHING TO FORM
ACROSS THE PLAINS BY 00Z...WHICH HELPS TO PULL NORTHEASTWARD THE
UPPER LOW NEAR TEXAS INTO SOUTHERN ILLINOIS. THE 22.12Z NAM IS THE
ONLY MODEL WHICH DOESNT PULL THE UPPER LOW NORTHEASTWARD...WHICH
APPEARS TO BE AN OUTLIER AND HAS BEEN DISCOUNTED. WITH THE APPROACH
OF BOTH THE UPPER TROUGH AND LOW IN THE AFTERNOON...DPVA FOR
VERTICAL MOTION INCREASES. THIS VERTICAL MOTION COMBINED WITH
PRECIPITABLE WATER CLIMBING TO 0.75-1 INCH...HIGHEST OVER THE
SOUTHEAST HALF OF THE FORECAST AREA...WILL LEAD TO AN INCREASE IN
SHOWER ACTIVITY...ESPECIALLY IN THE AFTERNOON. NOTE THAT THERE ARE
SIGNS FOR A FRONTOGENETIC BAND TO FORM STRETCHING SOUTHWEST TO
NORTHEAST ACROSS THE FORECAST AREA...WHICH MAY LEAD TO LESS
PRECIPITATION OVER THE FAR NORTHWEST SIDE OF THE FORECAST AREA.
OTHERWISE...ANY FOG FROM TONIGHT LOOKS TO DISSIPATE WEST TO EAST
THROUGH THE AFTERNOON...IN RESPONSE TO A COLD FRONT COMING INTO THE
WESTERN FORECAST AREA AND THE RAIN MOVING IN.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 313 PM CST SAT NOV 22 2014
SUNDAY NIGHT AND MONDAY...THIS PERIOD IS BECOMING MORE INTERESTING.
THERE ARE SIGNS IN THE 22.12Z GFS AND CANADIAN OF PHASING TAKING
PLACE...BETWEEN THE OVERALL UPPER TROUGH ACROSS THE PLAINS AND THE
CURRENT STRONG JET STREAK AT MEDFORD OREGON LIFTING INTO THE OHIO
VALLEY. THE GFS EVEN TAKES IT ONCE STEP FURTHER AND PHASES IN THE
TEXAS UPPER LOW. THE RESULT OF THE PHASING IS RAPID DEEPENING OF A
SURFACE LOW BETWEEN 00-12Z MONDAY MARCHING FROM MISSOURI TO NORTHERN
LAKE MICHIGAN. PRESSURES FALL FROM THE UPPER 980S TO LOW 970S OR
UPPER 960S MB. THE 22.09Z SREF NMMB MEMBERS AND SOME OF THE
CANADIAN ENSEMBLES ARE ALSO QUITE DEEP...EVEN MORESO THAN THE
GFS/CANADIAN. THESE DEEPER MODELS WOULD RESULT IN A TROWAL
OVER THE FORECAST AREA...LEADING TO A HEAVY SNOW BAND AND STRONG
WINDS. ALTHOUGH THERE HAS BEEN A TREND OF DEEPENING IN THE
AFOREMENTIONED MODELS...THE 22.12Z ECMWF REMAINS CONSISTENT IN A
MORE PROGRESSIVE/LESS PHASED SCENARIO. THE MODEL STILL HAS SNOW FOR
THE FORECAST AREA AFTER SOME EVENING RAIN...BUT THE F-GEN BAND IS
NOT NEARLY AS IMPRESSIVE. GIVEN THE CONSISTENCY IN THE ECMWF
AND THE MODEL BEING GENERALLY ONE OF THE BEST AT SYNOPTIC
VERIFICATION...FEEL IT IS DIFFICULT TO JUMP ON THE DEEP SCENARIOS
YET. THUS...THE FORECAST FOR SUNDAY NIGHT/MONDAY REMAINS LARGELY
UNCHANGED. DID BACK OFF THE BLOWING SNOW A BIT SINCE THE SNOWPACK
WILL BE GONE...ALLOWING ANY FALLING SNOW TO ACCUMULATE IN DITCHES
AND THUS LIMIT BLOWING. TEMPERATURE WISE...EXPECT A CONTINUOUS
FALLING TREND FROM SUNDAY NIGHT THROUGH MONDAY.
SNOW SHOULD GRADUALLY TAPER OFF MONDAY NIGHT AS THE LOW LIFTS
OFF TO THE NORTHEAST...BUT CONTINUED COLD AIR ADVECTION IS
ADVERTISED. 925MB TEMPS PLUNGE TO -10 TO -12C...WHICH SHOULD BRING
TEMPS DOWN INTO THE TEENS. TUESDAY FINALLY LOOKS LIKE A DRY
DAY...ASSOCIATED WITH SURFACE RIDGING COMING ACROSS AND AHEAD OF A
POTENT SHORTWAVE DROPPING INTO THE DAKOTAS. PRECIPITABLE WATER IS
QUITE DRY TOO...AROUND 0.2 OF AN INCH...WHICH SHOULD ALLOW ANY LOW
CLOUDS TO CLEAR TUESDAY MORNING. MORE HIGH CLOUDS ARE LIKELY TO
ARRIVE IN THE AFTERNOON...THOUGH. WITH 925MB TEMPS OF -8 TO -10C AT
18Z...HIGHS ONLY LOOK TO TOP OUT IN THE 20S.
TUESDAY NIGHT AND WEDNESDAY COULD BE INTERESTING AS WELL WITH THE
22.12Z ECMWF REMAINING CONSISTENT IN DRIVING A STORM SYSTEM
FROM THE DAKOTAS THROUGH THE REGION. THE 22.12Z/18Z NAM ARE SIMILAR
TOO...THOUGH THERE REALLY IS NO RESEMBLANCE OF THE SYSTEM IN THE
22.12Z GFS. THE 22.12Z CANADIAN IS LIKE A WEAKER NAM/ECMWF. SHOULD
THE ECMWF/NAM VERIFY...WE COULD BE LOOKING AT A 1-2 INCH
SNOWFALL...WHICH COULD IMPACT THANKSGIVING TRAVEL. FOR NOW HAVE TO
KEEP THE CHANCES LOWER...20-40...UNTIL BETTER MODEL AGREEMENT OCCURS.
HOWEVER WEDNESDAY PANS OUT...GOOD MODEL AGREEMENT EXISTS FOR ANOTHER
COLD SURGE TO DIVE INTO THE REGION FOR THANKSGIVING. 925MB TEMPS OF
-14 TO -16C ARE PROGGED...WHICH WOULD RESULT IN HIGHS ONLY IN THE
MID TEENS TO LOW 20S AT BEST. THIS COLD AIR LOOKS TO LINGER INTO THE
EARLY PART OF THE WEEKEND AS CANADIAN HIGH PRESSURE BUILDS IN.
GENERALLY CONDITIONS SHOULD BE DRY...THOUGH CANNOT RULE OUT A FEW
LIGHT SNOW PERIODS THAT DO NOT ACCUMULATE UP TO MUCH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1155 AM CST SAT NOV 22 2014
BIG PICTURE OF THIS FORECAST CYCLE FOR THE TAFS WAS ABUNDANT
MOISTURE AND SOUTHERLY WARM FLOW IN THE LOW LEVELS WILL PROMOTE
AN IFR FORECAST THROUGHOUT THE PERIOD. IT IS QUITE LIKELY WE WILL
SEE EXTENDED LIFR CONDITIONS IN THE OVERNIGHT AND MORNING SUNDAY.
WE WILL LIKELY SEE IFR CONDITIONS THROUGH COLD FRONT PASSAGE TIME
WHICH WILL COME SUNDAY NIGHT. HOWEVER...SHOULD SNOW OCCUR...IFR
CONDITIONS ARE EXPECTED SUNDAY NIGHT INTO MONDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BAUMGARDT