Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 10/12/12
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
624 PM PDT THU OCT 11 2012
.UPDATE...
LARGE BAND OF SHOWERS AND ISOLATED THUNDERSTORMS IS NOW MOVING
INTO MINERAL COUNTY AND SOON INTO MONO COUNTY. HRRR SEEMS TO BE
HANDLING THIS FAIRLY WELL RIGHT NOW AND LIKE ITS IDEAS OF
WIDESPREAD SHOWERS THIS EVENING DOWN THERE. HAVE UPDATED TO
INCREASE POPS AND SHOWER COVERAGE FOR MOST OF MONO AND MINERAL
COUNTIES. ALSO BOOSTED QPF A BIT AVERAGE AMOUNTS LIKELY TO BE A
TENTH TO QUARTER INCH.
FURTHER NORTH, SOME SHOWERS ARE MOVING INTO EASTERN CHURCHILL AND
PERSHING COUNTIES AND APPEAR TO BE MORE SCATTERED AT THIS TIME.
WILL CONTINUE TO MONITOR CENTRAL NV DEVELOPMENT THIS EVENING AS A
SECOND BAND IS FORECAST TO DEVELOP FOR PORTIONS OF WEST CENTRAL
NEVADA. EXPECT TO BE UPDATING AGAIN WHEN THE HARDEST HIT AREAS
BECOME CLEARER. MOST LIKELY IT IS LOOKING LIKE THE LOVELOCK-
FERNLEY-MINDEN AREAS TO GET THE BRUNT OF IT RIGHT NOW. COULD SEE A
QUARTER INCH OF RAIN IN THIS SECOND BAND WITH LOCALLY HIGHER
AMOUNTS. WALLMANN
&&
.PREVIOUS DISCUSSION... /ISSUED 246 PM PDT THU OCT 11 2012/
SHORT TERM...
UPPER LOW OVER SOCAL TODAY CONTINUES TO SLING ANOMALOUS AMOUNTS
OF MOISTURE UP INTO NV, WITH GEFS PRECIP WATER ANOMALIES 3-4
STANDARD DEVIATIONS ABOVE NORMAL. DEFORMATION ZONE HELPED PRODUCE
WIDESPREAD AREA OF SHOWERS SOUTH OF HWY 50 EARLIER TODAY WITH
SNOW DOWN TO ~7 KFT FROM TIME TO TIME NEAR MAMMOTH. RECENT HRRR
HIGH RESOLUTION RUNS SHOW SHOWER ACTIVITY CONTINUING THIS EVENING
MAINLY SOUTH OF HWY 50, WITH EVEN SOME TSTM POTENTIAL. WILL
FOLLOW THIS GUIDANCE AND ALSO KEEP CHC OF SHOWERS INTO RENO/GREAT
BASIN AREAS BASED ON UPSTREAM RADAR TRENDS OVER CENTRAL NV.
PRIMARY CHALLENGE IS FOR LATE TONIGHT AND TOMORROW, AS ALL MODELS
DEVELOP A ROUGHLY N-S ORIENTED FRONTOGENETIC BAND OF PRECIP OVER
THE FORECAST AREA BUT POSITION IT IN A VARIETY OF LOCATIONS.
SHOULD NAM/SREF VERIFY THEN RENO/CARSON AREAS COULD GET A BURST OF
APPRECIABLE RAIN (SREF HAS 15-25% CHC OF 0.25" 6-12Z TONIGHT),
WHILE GFS/EC IS FURTHER EAST OVER GREAT BASIN. HAVE ATTEMPTED TO
INCORPORATE BOTH THESE POSSIBILITIES SINCE I HAVE NO REASON TO
FAVOR ONE OVER THE OTHER AT THIS TIME. SO FORECAST CONFIDENCE IS
SOMEWHAT LOW TO MODERATE FOR THIS PERIOD.
LOW EXPECTED TO TRANSLATE EASTWARD LATE FRI, WITH SHORTWAVE
RIDGING BUILDING IN OVER THE AREA SAT/SUN WITH WARMING TEMPS.
IMPRESSIVE 185KT JET AND ATMOSPHERIC RIVER EXPECTED TO CRASH
ONSHORE INTO THE PAC NW STARTING SUN/MON. MODELS HAVE TRENDED
DRIER FOR NE CA AND NW NV SO HAVE BACKED DOWN ON SHOWERS THERE,
BUT WITH PROXIMITY TO ACTIVE JET A FEW LIGHT SHOWERS CANNOT BE
RULED OUT SUN NIGHT.
CS
LONG TERM...MONDAY THROUGH THURSDAY...
SHORTWAVE AND PACIFIC JET MOVING ACROSS THE NORTHWEST US ON
MONDAY WILL KEEP NEARLY ALL PRECIP NORTH OF THE OREGON BORDER,
EXCEPT FOR A FEW LIGHT RAIN SHOWERS POSSIBLE IN FAR NORTHWEST NV
AND THE SURPRISE VALLEY. OTHERWISE, DRY CONDITIONS WILL PREVAIL
WITH SOME INCREASE IN WEST WINDS MONDAY AFTERNOON-EVENING AS THE
SHORTWAVE BRUSHES ACROSS NORTHERN NV. FOR THE REMAINDER OF NEXT
WEEK, MEDIUM RANGE GUIDANCE IS IN GOOD AGREEMENT WITH REBUILDING
FLAT RIDGE OVER CA-NV, KEEPING THE REGION DRY WITH LIGHTER WINDS
AND LESS CLOUD COVERAGE. MAX TEMPS FOR MON-THURS WILL BE ABOUT
5-10 DEGREES ABOVE NORMAL, WITH MID 70S TO NEAR 80 DEGREES IN
WESTERN NV AND MID-UPPER 60S IN THE TAHOE BASIN. MJD
AVIATION...
FOR KRNO-KTVL-KTRK, VFR CONDS WITH WIDESPREAD CIGS OF 4000-8000
FT AGL ARE EXPECTED THRU 06Z THIS EVE WITH ISOLD BANDS OF LIGHT
RAIN AND SHOWERS THIS EVE PRODUCING BRIEF MVFR CIGS. A LARGER BAND
OF STEADY MODERATE RAIN IS POSSIBLE LATE TONIGHT THRU FRI MORNING.
THE LOCATION OF THIS BAND REMAINS UNCERTAIN BUT IS MOST LIKELY TO
AFFECT WEST CENTRAL NV. SOME GUIDANCE DATA DOES EXTEND THIS BAND
WEST INTO KRNO AND THE TAHOE BASIN SO WILL KEEP SOME PROB30/TEMPO
MENTION FOR A FEW HOURS AROUND 12Z.
FOR KMMH, ADDITIONAL WRAP AROUND RAIN BANDS ARE POSSIBLE THIS
EVENING AND AGAIN ON FRIDAY PRODUCING MVFR CIGS AT TIMES, BUT SNOW
IS UNLIKELY DURING THE OPERATIONAL HOURS AT KMMH THIS EVENING AND
FRIDAY. MJD
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
810 PM MDT THU OCT 11 2012
.UPDATE...WILL CONTINUE FOG INTO MORNING HOURS AND EXTEND IT
ALONG PLATTE TO GREELEY AREA. OTHERWISE FORECAST LOOKS GOOD.
&&
.AVIATION...THE MAIN CONCERN WILL BE POTENTIAL FOG EARLY FRIDAY
MORNING THAT MAY IMPACT DIA AND BJC. THERE IS A HIGH PROBABILITY
OF FOG ALONG THE SOUTH PLATTE RIVER NORTH OF DENVER...IF THE FOG
SPREADS SOUTH AND MOVES ACROSS THE AIRPORTS CIGS AND VSBYS WILL
DROP INTO IFR CATEGORIES. THE MAIN THREAT OF FOG WILL BE 10Z TO
15Z. LATER IN THE DAY ISOLATED THUNDERSTORMS WILL BE POSSIBLE
BEGINNING AROUND NOON AND CONTINUING UNTIL EARLY EVENING.
&&
.PREV DISCUSSION... /ISSUED 347 PM MDT THU OCT 11 2012/
SHORT TERM... FRONT PASSED ACROSS PLAINS DURING THE MORNING HOURS
WITH NORTHEAST WINDS PERSISTING THOUGH SLOWING DECREASING. HIGH
LEVEL MOISTURE IN PLACE OVER AREA WITH SOME CUMULUS ACROSS MOUNTAINS
ABOVE WEAK INVERSION. RADAR SHOWING SOME WEAK ECHOES OVER ZONE 34
WHERE LAPS SURFACE ANALYSIS INDICATING SOME CAPE. LATEST RUC KEEPS
SOME CAPE IN THIS AREA DURING THE EVENING...AND WILL CONTINUE WITH A
SLIGHT CHANCE OF THUNDERSTORMS THERE. OTHERWISE...SHOULD CONTINUE TO
SEE AN INCREASE IN MID AND HIGH LEVEL MOISTURE TONIGHT AS UPPER LOW
MOVES INTO THE DESERT SOUTHWEST. MODEL CROSS SECTIONS SHOW A GRADUAL
LOWERING OF THE MOISTURE AFTER MIDNIGHT ALONG WITH SOME INCREASE IN
MID LEVEL QG ASCENT. SOME SHOWERS POSSIBLE ACROSS THE MOUNTAINS
OVERNIGHT. AIRMASS STILL FAIRLY WARM SO SNOW LEVEL WILL BE RATHER
HIGH WITH NO ACCUMULATION. ACROSS PLAINS...WINDS TO BECOME SOUTHEAST
AND WEAKEN DURING THE EVENING WITH ONLY A SLIGHT INCREASE IN LOW
LEVEL MOISTURE AFTER MIDNIGHT. WITH THE LIGHT WINDS AND COOLER
AIRMASS...DECIDED TO KEEP THE MENTION OF PATCHY FOG ACROSS THE
NORTHERN SECTIONS OF THE URBAN CORRIDOR. ON FRIDAY...MODELS SHOW
UPPER LOW MOVING INTO SOUTHERN ARIZONA BY 18Z AND OVER SOUTHEAST
UTAH LATE IN THE AFTERNOON. SOUTHWEST FLOW ALOFT TO BECOME SOUTHERLY
WHICH WILL BRING MORE MOISTURE ACROSS THE AREA. THOUGH FLOW NOT
FAVORABLE FOR GOOD MOUNTAIN OROGRAPHICS...DECENT MOISTURE ALONG WITH
INCREASING QG VERTICAL MOTION AND INSTABILITY SUFFICIENT SHOULD BE
SUFFICIENT TO GENERATE NUMEROUS SHOWERS ALONG WITH SOME
THUNDERSTORMS ACROSS THE MOUNTAINS DURING THE AFTERNOON. AIRMASS
STILL FAIRLY WARM THROUGH THE AFTERNOON AND DESPITE THE POTENTIAL
FOR SOME EVAPORATIVE COOLING...SNOW LEVEL SHOULD REMAIN FAIRLY HIGH.
ANY ACCUMULATION TO BE CONFINED TO ELEVATIONS ABOVE 12000 FEET. AS
FOR PLAINS...SURFACE WINDS TO BECOME SOUTHEAST BY THE AFTERNOON WITH
THE POSSIBLE DEVELOPMENT OF A DENVER CYCLONE. THE SOUTHERLY FLOW
WILL ADVECT LOW LEVEL MOISTURE NORTHWARD. MODELS GENERATE CAPES OF
AROUND 300 J/KG ACROSS PALMER DIVIDE DURING THE AFTERNOON...LESS
FURTHER NORTH. SO BEST CHANCE OF STORMS TO BE ALONG PALMER DIVIDE
NORTHEAST INTO SOUTHERN WASHINGTON COUNTY. GUIDANCE TEMPERATURES
FAIRLY CLOSE ACROSS THE AREA THOUGH COULD BE A BIT TOO WARM BASED ON
POTENTIAL CLOUD COVER.
LONG TERM...THE UPPER CLOSED LOW IS OVER THE NORTHEAST CORNER OF
COLORADO AT 12Z SATURDAY. THE UPPER TROUGH AXIS GETS EAST OF THE
CWA BY EARLY SATURDAY AFTERNOON. NORTHWESTERLY FLOW ALOFT WILL
DOMINATE AFTER TROUGH PASSAGE THROUGH SUNDAY NIGHT. THERE IS PRETTY
DECENT UPWARD SYNOPTIC SCALE ENERGY PROGGED ON THE QG VERTICAL
VELOCITY FIELDS FRIDAY NIGHT INTO SATURDAY MORNING. BY 18Z...PRETTY
STRONG DOWNWARD MOTION IS EXPECTED. BY 06Z SATURDAY NIGHT THROUGH
SUNDAY NIGHT...THERE IS BENIGN ENERGY IN THE SYNOPTIC SCALE. THE
BOUNDARY LAYER FLOW IS PROGGED TO BE DOWNSLOPING AS THE TROUGH
PASSES SATURDAY MORNING. THERE IS A BRIEF SHOT OF FAIRLY STRONG
NORTHWESTERLIES SATURDAY MORNING. THE DOWNSLOPING RELAXES BY
SATURDAY EVENING...WITH NORMAL DIURNAL PATTERNS EXPECTED THE REST OF
THE NIGHT THROUGH SUNDAY NIGHT. FOR MOISTURE...IT IS DEEP OVER THE
MOUNTAINS FRIDAY NIGHT THROUGH SATURDAY. EVEN SATURDAY NIGHT IT IS
PRETTY GOOD...BUT DECREASES SUNDAY MORNING. FOR THE PLAINS...
MOISTURE IS ONLY FAIR FRIDAY NIGHT...THAT AREA IS IN THE DRY SLOT OF
THE MID LATITUDE CYCLONE. MOISTURE GETS BETTER ON SATURDAY ON THE
BACKSIDE OF THE CLOSED LOW...AND IT LINGERS AROUND SATURDAY EVEN
OVER THE EASTERN HALF OF THE PLAINS. ON SUNDAY...MOISTURE DECREASES
OVER ALL THE CWA...SUNDAY NIGHT TOO. PRECIPITABLE WATER VALUES ARE
IN THE 0.40 TO 0.60 INCH RANGE LATER FRIDAY NIGHT AND SATURDAY
..THEN THEY DECREASE ON SUNDAY. THERE IS SOME CAPE OVER THE
EASTERN HALF OF THE PLAINS FRIDAY EVENING...VALUES ARE UP TO 500
J/KG. THAT IS IT FOR CAPE...THERE IS NONE SATURDAY OR SUNDAY FOR
THE CWA. FOR MOUNTAIN POPS...PRECIPITATION IS A VERY GOOD BET
FRIDAY NIGHT INTO SATURDAY EVENING...INITIALLY WITH THE SYNOPTIC
SCALE ENERGY OF THE CLOSED LOW...THEN WITH ORTHOGRAPHIC ENHANCEMENT
BY SATURDAY AFTERNOON. SO WILL GO WITH 60-80%S FRIDAY NIGHT INTO
SATURDAY EVENING. THEN DECREASE THEM DOWN TO NOTHING BY SUNDAY
MORNING SOMETIME. FOR THE PLAINS...THE FRONT RANGE AREA WILL HAVE
DRY SLOTTING...THEN PRETTY DECENT DRYING FROM DOWNSLOPING...SO POPS
WILL BE MINIMAL. BETTER POPS ARE EXPECTED FURTHER EAST...BUT NO
"LIKELY"S. WILL KEEP POPS GOING OVER THE FAR EAST INTO SATURDAY
NIGHT. SUNDAY AND SUNDAY NIGHT ARE DRY. WILL NOT GO WITH ANY
HIGHLIGHTS RIGHT NOW. NOT SURE IF THERE WILL BE ENOUGH MOISTURE FOR
ADVISORY AMOUNTS. FOR TEMPERATURES...SATURDAY`S HIGHS ARE SIMILAR
TO FRIDAY`S. SUNDAY`S HIGHS ARE 1-3 C WARMER THAN SATURDAY`S. FOR
THE LATER DAYS...MONDAY THROUGH THURSDAY...NORTHWESTERLY FLOW ALOFT
WILL CONTINUE OVER THE CWA ALL FOUR DAYS. FROM 12Z TUESDAY THROUGH
WEDNESDAY AFTERNOON...THE FLOW ALOFT IS WELL OVER 100 KNOTS. A COLD
FRONT IS PROGGED TO MOVE IN TUESDAY NIGHT AS WELL. MOISTURE IS VERY
SPARSE.
AVIATION...NORTHEAST SURFACE WINDS TO WEAKEN AND SHIFT TO THE
SOUTHEAST DURING THE EVENING TRANSITIONING TO DRAINAGE FLOW
OVERNIGHT. SLIGHT CHANCE FOR SOME PATCHY FOG DEVELOPING IN THE
15Z-18Z TIME FRAME NORTH OF THE DENVER AREA...SHOULD NOT AFFECT AREA
AIRPORTS. WINDS TO SHIFT TO THE SOUTHEAST BY 18Z FRIDAY WITH THE
POTENTIAL FOR THE DEVELOPMENT OF A DENVER CYCLONE ACROSS SOUTHERN
WELD COUNTY. THUS WINDS COULD BE NORTHWEST AT KBJC AND SOUTHERLY AT
KDEN AND KAPA. HIGH LEVEL MOISTURE WILL INCREASE OVERNIGHT ALONG
WITH SOME MID LEVEL MOISTURE. BY 18Z FRIDAY...LOW LEVEL MOISTURE TO
SPREAD ACROSS PLAINS WITH A SLIGHT CHANCE FOR RAIN SHOWERS. VFR
CONDITIONS TO PREVAIL...WITH POTENTIAL FOR CEILINGS AROUND 6000 FEET
AGL.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...99
LONG TERM....99
AVIATION...RTG
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1240 PM CDT WED OCT 10 2012
.DISCUSSION...
ISSUED 1055 AM CDT WED OCT 10 2012
NO MAJOR CHANGES MADE TO THE FORECAST LATE THIS MORNING. HIGH
PRESSURE CENTERED IN EASTERN KS CONTINUED TO ADVECT LOW LEVEL DRY
AIR FROM THE WEST INTO CENTRAL AND EASTERN IL. THE VISIBLE
SATELLITE INDICATES A FEW CUMULUS DEVELOPING IN EASTERN IL...BUT
THE LOW LEVEL MOISTURE PROJECTIONS ON THE NAM...GFS AND HRRR ALL
POINT TO CONTINUED DRYING AND NO INCREASE IN AREAL EXTENT OF
CLOUDS.
TEMPERATURES IN THE 45-50 RANGE ARE ONLY EXPECTED TO CLIMB ANOTHER
5-10 DEGREES WITH HIGHS MAINLY IN THE MID 50S ANTICIPATED. THE
SURFACE WIND IS NOT EXPECTED TO BACK TO THE SOUTH AND INCREASE UNTIL
LATER THIS EVENING/TONIGHT. THIS SHOULD KEEP PATCHY FROST CONFINED
TO EASTERN IL EARLY THURSDAY MORNING.
&&
.AVIATION...
ISSUED 1240 PM CDT WED OCT 10 2012
VFR CONDITIONS CAN BE EXPECTED IN ALL OF CENTRAL AND EASTERN IL
TAF SITES THE NEXT 24 HOURS.
HIGH PRESSURE IN WEST CENTRAL MO WILL SLIDE TO THE EAST SOUTHEAST
THIS AFTERNOON AND EVENING. LOW LEVEL MOISTURE IS RATHER SPARSE...
SO ONLY A FEW LOW TOPPED CU ARE ANTICIPATED THIS AFTERNOON. THE
PRESSURE GRADIENT WILL BE STRONG ENOUGH THIS AFTERNOON TO PRODUCE
GUSTY WEST-NORTHWEST WINDS.
THE SURFACE RIDGE AXIS WILL BE ACROSS CENTRAL IL AROUND
SUNSET...SO THIS WILL COMBINE WITH THE DIURNAL DECOUPLING OF THE
LOW ATMOSPHERE TO DROP THE WINDS OFF SIGNIFICANTLY PRIOR TO 00Z.
AFTER THE RIDGE AXIS PASSES TO THE EAST AROUND 04-06Z...THE WIND
WILL CONTINUE BACKING TO THE SOUTH-SOUTHWEST AND INCREASE A BIT.
AN INCREASING PRESSURE GRADIENT WEST OF THE DEPARTING HIGH WILL
RESULT IN RAPIDLY INCREASING WIND BY LATE THURSDAY MORNING. THE
NAM BUFKIT IS INDICATING PLENTY OF MOMENTUM TRANSFER IN THE LOWER
ATMOSPHERE...SO AM EXPECTING A SOUTHWEST WIND GUSTING AROUND 25
MPH AFTER 15Z.
MILLER
&&
.PREV DISCUSSION...
ISSUED 320 AM CDT WED OCT 10 2012
00Z MODELS ARE IN FAIR AGREEMENT NEXT FEW DAYS AND GENERALLY ARE
TRENDING SLOWER WITH STRONG LOW PRESSURE MOVING NE INTO THE
WESTERN GREAT LAKES BY SUNDAY MORNING. WILL USE A BLEND OF
GFS AND ECMWF MODELS FOR HANDLING STRONG STORM SYSTEM THIS WEEKEND.
MET AND MAV TEMPS SIMILAR THROUGH FRIDAY AND STAYED CLOSE TO.
SHORT TERM...TODAY THROUGH FRIDAY
STRONG 995 MB LOW PRESSURE ALONG THE WESTERN SHORES OF JAMES BAY
CANADA HAD A COLD FRONT THROUGH CENTRAL INDIANA INTO EXTREME SE IL/MO
AND HAS RECENTLY WENT THROUGH LAWRENCEVILLE AND MOUNT CARMEL
AIRPORTS OVER SOUTHEAST LAWRENCE COUNTY. COLD FRONTAL PASSAGE IS
MARKED BY GUSTY NW WINDS WITH GUSTS 20 TO 25 MPH AND MOST OF THE
VERY LIGHT RAIN SHOWERS BEHIND THE COLD FRONT OVER EASTERN IL HAVE
DISSIPATED. SHARP CLEARING LINE PROGESSING SE TOWARD A CHAMPAIGN
TO SHELBYVILLE LINE EARLY THIS MORNING. THIS CLEARING LINE SHOULD
REACH LAWRENCEVILLE BY SUNRISE (12Z/7 AM).
1025 MB HIGH PRESSURE OVER NEBRASKA/KS TO SETTLE EAST INTO THE MID
MS VALLEY BY SUNSET BRINGING PLENTY OF SUNSHINE TODAY ALONG WITH
COOLER HIGHS IN THE MID 50S...EXCEPT UPPER 50S IN SE IL WITH BREEZY
NW WINDS. HIGH PRESSURE RIDGE STRENGTHENS TO 1027 MB OVER EASTERN
KY AND WV BY DAWN THU AND TO BRING CHILLY LOWS IN THE MID TO UPPER
30S TONIGHT WITH CLEAR SKIES. COOLEST READINGS IN EASTERN IL WHERE
LIGHTER WINDS AND PATCHY FROST LIKELY TO DEVELOP DURING OVERNIGHT
INTO EARLY THU MORNING.
MODELS HAVE TRENDED FURTHER SOUTH WITH 1031 MB HIGH PRESSURE
MOVING INTO THE UPPER MS VALLEY OVERNIGHT THU NIGHT ALONG WITH A
WEAK FRONTAL BOUNDARY SETTLING INTO THE MID MS VALLEY THU NIGHT.
QPF FIELDS HAVE SHIFTED A BIT SOUTHWARD AS WELL WITH AREAS NORTH
OF I-72 LIKELY STAYING DRY WITH CHANCE OF SHOWERS AND ISOLATED
THUNDERSTORMS SOUTH OF I-72 AND BEST CHANCES SSW OF A TAYLORVILLE
TO ROBINSON LINE.
HIGH PRESSURE DRIFTS EAST ACROSS THE GREAT LAKES REGION FRIDAY AND
PUSHING THE FRONT AND ITS PRECIPITION CHANCES FURTHER SOUTH SO
EXPECT DRY CONDITIONS ACROSS CENTRAL/SE IL FRIDAY WITH MORE SUNSHINE
OVER NORTHERN/NE AREAS. HIGHS THU AND FRI IN THE LOW TO MID 60S.
LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
STRONG 560 DM 500 MB LOW STILL SPINNING OFF THE CENTRAL CA COAST
TO DIVE INTO SOUTHERN CA BY MIDNIGHT THU NIGHT AND THEN EJECT NE
INTO THE CENTRAL ROCKIES BY MIDNIGHT FRI NIGHT AND INTO THE
WESTERN GREAT LAKES SUNDAY MORNING. SURFACE LOW PRESSURE DEVELOPS
OVER EASTERN CO FRI AND DEEPENS NE INTO THE WESTERN GREAT LAKES BY
SUNDAY MORNING. MODELS HAVE TRENDED SLOWER WITH THIS STRONG LOW
PRESSURE SYSTEM WITH ECMWF AND GEM MODELS SLOWER THAN THE GFS
MODEL. FRIDAY EVENING SHOULD STILL BE DRY WITH WARM AIR ADVECTION
DRIVEN CONVECTION DEVELOPING FROM THE WEST AFTER MIDNIGHT FRI
NIGHT INTO SAT MORNING WITH HIGHEST CHANCES OVER THE IL RIVER
VALLEY. LIKELY TO BE A LULL IN CONVECTION CHANCES LATER SAT
MORNING AND AFTERNOON. THEN INCREASING CHANCES OF SHOWERS AND
THUNDERSTORMS FROM WEST TO EAST DURING SAT NIGHT AND LINGERING
OVER EASTERN IL SUNDAY MORNING. SEVERE RISK STILL SEEMS POSSIBLE
SAT NIGHT WHILE HEAVIEST RAINS APPEAR TO BE NW OF CENTRAL IL OVER
IA/WI AND NW IL CLOSER TO LOW PRESSURE TRACK. MODELS HAVE TRENDED
DRIER MONDAY AND MONDAY NIGHT WITH NEXT CHANCE OF SHOWERS AND
POSSIBLE THUNDERSTORMS ARRIVING LATER TUE INTO WED AS ANOTHER COLD
FRONT APPROACHES IL.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1055 AM CDT WED OCT 10 2012
.DISCUSSION...
ISSUED 1055 AM CDT WED OCT 10 2012
NO MAJOR CHANGES MADE TO THE FORECAST LATE THIS MORNING. HIGH
PRESSURE CENTERED IN EASTERN KS CONTINUED TO ADVECT LOW LEVEL DRY
AIR FROM THE WEST INTO CENTRAL AND EASTERN IL. THE VISIBLE
SATELLITE INDICATES A FEW CUMULUS DEVELOPING IN EASTERN IL...BUT
THE LOW LEVEL MOISTURE PROJECTIONS ON THE NAM...GFS AND HRRR ALL
POINT TO CONTINUED DRYING AND NO INCREASE IN AREAL EXTENT OF
CLOUDS.
TEMPERATURES IN THE 45-50 RANGE ARE ONLY EXPECTED TO CLIMB ANOTHER
5-10 DEGREES WITH HIGHS MAINLY IN THE MID 50S ANTICIPATED. THE
SURFACE WIND IS NOT EXPECTED TO BACK TO THE SOUTH AND INCREASE UNTIL
LATER THIS EVENING/TONIGHT. THIS SHOULD KEEP PATCHY FROST CONFINED
TO EASTERN IL EARLY THURSDAY MORNING.
MILLER
&&
.AVIATION...
ISSUED 630 AM CDT WED OCT 10 2012
VFR CONDITIONS WILL PREVAIL THRU THIS FORECAST PERIOD. THE COLD
FRONT THAT BROUGHT THE LIGHT RAINFALL AND BRIEF MVFR CIGS HAS
SHIFTED WELL OFF TO OUR EAST THIS MORNING. ANOTHER COOL CANADIAN
HIGH WILL BUILD ACRS THE MIDWEST TODAY RESULTING IN SOME GUSTY
WEST TO NORTHWEST WINDS. FORECAST SOUNDINGS SHOWING JUST ENOUGH
MOISTURE BETWEEN 3500-5000 FEET FOR SOME SCATTERED CU TO FORM
LATER THIS MORNING. WIND GUSTS TO 20 KTS POSSIBLE LATE THIS
MORNING INTO EARLY THIS AFTERNOON BEFORE SFC WINDS START TO
BACK MORE INTO A WEST DIRECTION AFTR 20Z...AND THEN INTO THE
SOUTH AT 5 TO 10 KTS THIS EVENING.
SMITH
&&
.PREV DISCUSSION...
ISSUED 320 AM CDT WED OCT 10 2012
00Z MODELS ARE IN FAIR AGREEMENT NEXT FEW DAYS AND GENERALLY ARE
TRENDING SLOWER WITH STRONG LOW PRESSURE MOVING NE INTO THE
WESTERN GREAT LAKES BY SUNDAY MORNING. WILL USE A BLEND OF
GFS AND ECMWF MODELS FOR HANDLING STRONG STORM SYSTEM THIS WEEKEND.
MET AND MAV TEMPS SIMILAR THROUGH FRIDAY AND STAYED CLOSE TO.
SHORT TERM...TODAY THROUGH FRIDAY
STRONG 995 MB LOW PRESSURE ALONG THE WESTERN SHORES OF JAMES BAY
CANADA HAD A COLD FRONT THROUGH CENTRAL INDIANA INTO EXTREME SE IL/MO
AND HAS RECENTLY WENT THROUGH LAWRENCEVILLE AND MOUNT CARMEL
AIRPORTS OVER SOUTHEAST LAWRENCE COUNTY. COLD FRONTAL PASSAGE IS
MARKED BY GUSTY NW WINDS WITH GUSTS 20 TO 25 MPH AND MOST OF THE
VERY LIGHT RAIN SHOWERS BEHIND THE COLD FRONT OVER EASTERN IL HAVE
DISSIPATED. SHARP CLEARING LINE PROGESSING SE TOWARD A CHAMPAIGN
TO SHELBYVILLE LINE EARLY THIS MORNING. THIS CLEARING LINE SHOULD
REACH LAWRENCEVILLE BY SUNRISE (12Z/7 AM).
1025 MB HIGH PRESSURE OVER NEBRASKA/KS TO SETTLE EAST INTO THE MID
MS VALLEY BY SUNSET BRINGING PLENTY OF SUNSHINE TODAY ALONG WITH
COOLER HIGHS IN THE MID 50S...EXCEPT UPPER 50S IN SE IL WITH BREEZY
NW WINDS. HIGH PRESSURE RIDGE STRENGTHENS TO 1027 MB OVER EASTERN
KY AND WV BY DAWN THU AND TO BRING CHILLY LOWS IN THE MID TO UPPER
30S TONIGHT WITH CLEAR SKIES. COOLEST READINGS IN EASTERN IL WHERE
LIGHTER WINDS AND PATCHY FROST LIKELY TO DEVELOP DURING OVERNIGHT
INTO EARLY THU MORNING.
MODELS HAVE TRENDED FURTHER SOUTH WITH 1031 MB HIGH PRESSURE
MOVING INTO THE UPPER MS VALLEY OVERNIGHT THU NIGHT ALONG WITH A
WEAK FRONTAL BOUNDARY SETTLING INTO THE MID MS VALLEY THU NIGHT.
QPF FIELDS HAVE SHIFTED A BIT SOUTHWARD AS WELL WITH AREAS NORTH
OF I-72 LIKELY STAYING DRY WITH CHANCE OF SHOWERS AND ISOLATED
THUNDERSTORMS SOUTH OF I-72 AND BEST CHANCES SSW OF A TAYLORVILLE
TO ROBINSON LINE.
HIGH PRESSURE DRIFTS EAST ACROSS THE GREAT LAKES REGION FRIDAY AND
PUSHING THE FRONT AND ITS PRECIPITION CHANCES FURTHER SOUTH SO
EXPECT DRY CONDITIONS ACROSS CENTRAL/SE IL FRIDAY WITH MORE SUNSHINE
OVER NORTHERN/NE AREAS. HIGHS THU AND FRI IN THE LOW TO MID 60S.
LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
STRONG 560 DM 500 MB LOW STILL SPINNING OFF THE CENTRAL CA COAST
TO DIVE INTO SOUTHERN CA BY MIDNIGHT THU NIGHT AND THEN EJECT NE
INTO THE CENTRAL ROCKIES BY MIDNIGHT FRI NIGHT AND INTO THE
WESTERN GREAT LAKES SUNDAY MORNING. SURFACE LOW PRESSURE DEVELOPS
OVER EASTERN CO FRI AND DEEPENS NE INTO THE WESTERN GREAT LAKES BY
SUNDAY MORNING. MODELS HAVE TRENDED SLOWER WITH THIS STRONG LOW
PRESSURE SYSTEM WITH ECMWF AND GEM MODELS SLOWER THAN THE GFS
MODEL. FRIDAY EVENING SHOULD STILL BE DRY WITH WARM AIR ADVECTION
DRIVEN CONVECTION DEVELOPING FROM THE WEST AFTER MIDNIGHT FRI
NIGHT INTO SAT MORNING WITH HIGHEST CHANCES OVER THE IL RIVER
VALLEY. LIKELY TO BE A LULL IN CONVECTION CHANCES LATER SAT
MORNING AND AFTERNOON. THEN INCREASING CHANCES OF SHOWERS AND
THUNDERSTORMS FROM WEST TO EAST DURING SAT NIGHT AND LINGERING
OVER EASTERN IL SUNDAY MORNING. SEVERE RISK STILL SEEMS POSSIBLE
SAT NIGHT WHILE HEAVIEST RAINS APPEAR TO BE NW OF CENTRAL IL OVER
IA/WI AND NW IL CLOSER TO LOW PRESSURE TRACK. MODELS HAVE TRENDED
DRIER MONDAY AND MONDAY NIGHT WITH NEXT CHANCE OF SHOWERS AND
POSSIBLE THUNDERSTORMS ARRIVING LATER TUE INTO WED AS ANOTHER COLD
FRONT APPROACHES IL.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
225 PM MDT WED OCT 10 2012
.UPDATE...
ISSUED AT 225 PM MDT WED OCT 10 2012
MADE MINOR ADJUSTMENT TO WX/SKY GRIDS FOR TONIGHT PERIOD...TO
INCREASE SKY COVER AND ADD PATCHY FOG. NAM/RUC BOTH SHOWING DECENT
BL MOISTURE ADVECTING NORTH. WITH BETTER CLEARING SOUTH
COULDNT RULE OUT STRATUS/FOG DEVELOPING AND THEN ADVECTING NORTH
OUT OF SE CO AND SW KS. NOT SURE HOW FAR NORTH THIS WILL GET...SO
I ONLY LIMITED IT TO THE FAR SOUTHERN TIER OF COUNTIES.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 1203 PM MDT WED OCT 10 2012
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOW SIMILAR PATTERN AS THE
LAST FEW DAYS...WITH BROAD TROUGH ACROSS CANADA EXTENDING SOUTH
ACROSS THE EASTERN US. A REX BLOCK IS ALSO STILL IN PLACE OFF THE
WESTERN US...WITH A CLOSED UPPER LOW BEGINNING TO MOVE OVER THE
CENTRAL CALIFORNIA COAST. A SHORTWAVE RIDGE EXTENDS NORTH OVER
WESTERN COLORADO AND TOWARDS THE GREAT BASIN. AT THE SURFACE HIGH
PRESSURE EXTENDS FROM THE CENTRAL MISSISSIPPI VALLEY WEST INTO
CENTRAL KANSAS. A LEE TROUGH IS DEEPENING OVER EASTERN
COLORADO...WITH INCREASING PRESSURE GRADIENT OVER WESTERN KS BETWEEN
THESE FEATURES.
GOOD WAA OVERNIGHT TONIGHT...COMBINED WITH MID-HIGH CLOUD COVER
COMPLICATES THE LOW TEMPERATURE. WINDS SHOULD DIMINISH AROUND
SUNSET AS DAYTIME HEATING COMES TO AN END...AND THE LEE TROUGH
AXIS SHIFTS EAST OVER THE CWA...SO WINDS SHOULD NOT BE AS MUCH OF
AN ISSUE. TEMPERATURES CURRENTLY EXPECTED TO BE IN THE 40S ACROSS
MOST OF THE AREA. IF CLOUD COVER WERE TO BE MORE EXTENSIVE WE
MAY SEE OVERNIGHT TEMPS CLOSER TO 50F AT SOME LOCATIONS.
A COLD FRONT WILL PUSH SOUTH OVER THE CWA AS A SHORTWAVE TROUGH
MOVES FROM SOUTHERN CANADA INTO NORTHERN MINNESOTA THURSDAY. WITH
VERY LITTLE IN MOISTURE IN PLACE AND BEST LARGE SCALE ASCENT WELL TO
THE NORTH AND EAST...NO PRECIP IS EXPECTED. LATEST GUIDANCE FAVORS
FRONTAL PASSAGE AROUND 15Z ACROSS MOST OF THE CWA...AND AROUND 18Z
ACROSS THE SOUTHERN HALF OF THE CWA. I HAVE TRENDED TEMPS DOWN
ACCORDINGLY...WITH HIGHS IN THE UPPER 50S/LOW 60S ACROSS THE
NORTH...AND NEAR 70 ACROSS THE SOUTH.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 1251 PM MDT WED OCT 10 2012
SYSTEM CURRENTLY OVER SOUTHERN CALIFORNIA WILL LIFT OUT ACROSS THE
SOUTHERN AND CENTRAL ROCKIES FRIDAY AND SATURDAY. BEST LIFT LOCALLY
WILL OCCUR FRIDAY AFTERNOON THROUGH FRIDAY NIGHT. COOL AND STABLE
CONDITIONS ARE FORECAST FOR FRIDAY WHICH WILL RESULT IN SURFACE
INSTABILITY OF ZERO. HOWEVER...THERE IS WEAK ELEVATED INSTABILITY
AND DEEP LAYER SHEAR IS UP TO 40KTS. THERE IS SOME WEAK SURFACE
BASED INSTABILITY FORECAST LATE FRIDAY NIGHT...SO CANNOT RULE OUT
THE POSSIBILITY OF A SEVERE STORM MOVING INTO AREAS SOUTH OF INTERSTATE
70 FROM SOUTHWEST KANSAS FRIDAY NIGHT. AFTER MIDNIGHT A MASSIVE
MID LEVEL DRY SLOT WILL OVERSPREAD THE FORECAST AREA...ENDING THE
PRECIPITATION CHANCES FOR ALL BUT THE FAR NORTHWEST CORNER WHICH
COULD RECEIVE SOME LIGHT WRAPAROUND PRECIPITATION THROUGH SATURDAY
MORNING. CLEARING IS EXPECTED BY SATURDAY AFTERNOON FOR THE ENTIRE
AREA.
RIDGING IS FORECAST FOR SUNDAY AND MONDAY WITH ABOVE NORMAL
TEMPERATURES AND DRY CONDITIONS. NEXT SHORTWAVE TROUGH WILL
APPROACH THE NORTHERN ROCKIES MONDAY NIGHT AND MOVE ACROSS THE
AREA TUESDAY OR WEDNESDAY. HOWEVER...MOISTURE APPEARS TO BE
LACKING FOR PRECIPITATION CHANCES. ASSOCIATED SURFACE COLD FRONT
COULD PRODUCE WINDY CONDITIONS TUESDAY NIGHT AND WEDNESDAY GIVEN
STRONG UPPER JET IN THE VICINITY. ONLY SLIGHT COOLING IS EXPECTED
WITH FRONTAL PASSAGE GIVEN PACIFIC ORIGIN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1124 AM MDT WED OCT 10 2012
VFR CONDITIONS WILL CONTINUE THROUGH THE PERIOD AT BOTH KGLD AND
MCK TERMINALS. SOUTH WINDS 15 TO 20 KTS ARE EXPECTED AT BOTH
TERMINALS THROUGH THIS AFTERNOON...WITH GUSTS AROUND 30 KTS. THESE
WINDS WILL DECREASE AROUND SUNSET AND BECOME LIGHT AND VARIABLE AS
THE SURFACE TROUGH OVER EASTERN COLORADO SHIFTS EAST. WINDS WILL
SHIFT TO THE NORTH AND INCREASE BETWEEN 14-15Z THURSDAY AS A COLD
FRONT DROPS SOUTH OVER BOTH TERMINALS. WIND GUSTS AROUND 25 KTS
ARE EXPECTED IMMEDIATELY BEHIND THE FRONT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...DR
SHORT TERM...DR
LONG TERM...024
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
111 PM MDT WED OCT 10 2012
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 1203 PM MDT WED OCT 10 2012
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOW SIMILAR PATTERN AS THE
LAST FEW DAYS...WITH BROAD TROUGH ACROSS CANADA EXTENDING SOUTH
ACROSS THE EASTERN US. A REX BLOCK IS ALSO STILL IN PLACE OFF THE
WESTERN US...WITH A CLOSED UPPER LOW BEGINNING TO MOVE OVER THE
CENTRAL CALIFORNIA COAST. A SHORTWAVE RIDGE EXTENDS NORTH OVER
WESTERN COLORADO AND TOWARDS THE GREAT BASIN. AT THE SURFACE HIGH
PRESSURE EXTENDS FROM THE CENTRAL MISSISSIPPI VALLEY WEST INTO
CENTRAL KANSAS. A LEE TROUGH IS DEEPENING OVER EASTERN
COLORADO...WITH INCREASING PRESSURE GRADIENT OVER WESTERN KS BETWEEN
THESE FEATURES.
GOOD WAA OVERNIGHT TONIGHT...COMBINED WITH MID-HIGH CLOUD COVER
COMPLICATES THE LOW TEMPERATURE. WINDS SHOULD DIMINISH AROUND
SUNSET AS DAYTIME HEATING COMES TO AN END...AND THE LEE TROUGH
AXIS SHIFTS EAST OVER THE CWA...SO WINDS SHOULD NOT BE AS MUCH OF
AN ISSUE. TEMPERATURES CURRENTLY EXPECTED TO BE IN THE 40S ACROSS
MOST OF THE AREA. IF CLOUD COVER WERE TO BE MORE EXTENSIVE WE
MAY SEE OVERNIGHT TEMPS CLOSER TO 50F AT SOME LOCATIONS.
A COLD FRONT WILL PUSH SOUTH OVER THE CWA AS A SHORTWAVE TROUGH
MOVES FROM SOUTHERN CANADA INTO NORTHERN MINNESOTA THURSDAY. WITH
VERY LITTLE IN MOISTURE IN PLACE AND BEST LARGE SCALE ASCENT WELL TO
THE NORTH AND EAST...NO PRECIP IS EXPECTED. LATEST GUIDANCE FAVORS
FRONTAL PASSAGE AROUND 15Z ACROSS MOST OF THE CWA...AND AROUND 18Z
ACROSS THE SOUTHERN HALF OF THE CWA. I HAVE TRENDED TEMPS DOWN
ACCORDINGLY...WITH HIGHS IN THE UPPER 50S/LOW 60S ACROSS THE
NORTH...AND NEAR 70 ACROSS THE SOUTH.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 1251 PM MDT WED OCT 10 2012
SYSTEM CURRENTLY OVER SOUTHERN CALIFORNIA WILL LIFT OUT ACROSS THE
SOUTHERN AND CENTRAL ROCKIES FRIDAY AND SATURDAY. BEST LIFT LOCALLY
WILL OCCUR FRIDAY AFTERNOON THROUGH FRIDAY NIGHT. COOL AND STABLE
CONDITIONS ARE FORECAST FOR FRIDAY WHICH WILL RESULT IN SURFACE
INSTABILITY OF ZERO. HOWEVER...THERE IS WEAK ELEVATED INSTABILITY
AND DEEP LAYER SHEAR IS UP TO 40KTS. THERE IS SOME WEAK SURFACE
BASED INSTABILITY FORECAST LATE FRIDAY NIGHT...SO CANNOT RULE OUT
THE POSSIBILITY OF A SEVERE STORM MOVING INTO AREAS SOUTH OF INTERSTATE
70 FROM SOUTHWEST KANSAS FRIDAY NIGHT. AFTER MIDNIGHT A MASSIVE
MID LEVEL DRY SLOT WILL OVERSPREAD THE FORECAST AREA...ENDING THE
PRECIPITATION CHANCES FOR ALL BUT THE FAR NORTHWEST CORNER WHICH
COULD RECEIVE SOME LIGHT WRAPAROUND PRECIPITATION THROUGH SATURDAY
MORNING. CLEARING IS EXPECTED BY SATURDAY AFTERNOON FOR THE ENTIRE
AREA.
RIDGING IS FORECAST FOR SUNDAY AND MONDAY WITH ABOVE NORMAL
TEMPERATURES AND DRY CONDITIONS. NEXT SHORTWAVE TROUGH WILL
APPROACH THE NORTHERN ROCKIES MONDAY NIGHT AND MOVE ACROSS THE
AREA TUESDAY OR WEDNESDAY. HOWEVER...MOISTURE APPEARS TO BE
LACKING FOR PRECIPITATION CHANCES. ASSOCIATED SURFACE COLD FRONT
COULD PRODUCE WINDY CONDITIONS TUESDAY NIGHT AND WEDNESDAY GIVEN
STRONG UPPER JET IN THE VICINITY. ONLY SLIGHT COOLING IS EXPECTED
WITH FRONTAL PASSAGE GIVEN PACIFIC ORIGIN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1124 AM MDT WED OCT 10 2012
VFR CONDITIONS WILL CONTINUE THROUGH THE PERIOD AT BOTH KGLD AND
MCK TERMINALS. SOUTH WINDS 15 TO 20 KTS ARE EXPECTED AT BOTH
TERMINALS THROUGH THIS AFTERNOON...WITH GUSTS AROUND 30 KTS. THESE
WINDS WILL DECREASE AROUND SUNSET AND BECOME LIGHT AND VARIABLE AS
THE SURFACE TROUGH OVER EASTERN COLORADO SHIFTS EAST. WINDS WILL
SHIFT TO THE NORTH AND INCREASE BETWEEN 14-15Z THURSDAY AS A COLD
FRONT DROPS SOUTH OVER BOTH TERMINALS. WIND GUSTS AROUND 25 KTS
ARE EXPECTED IMMEDIATELY BEHIND THE FRONT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...024
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1203 PM MDT WED OCT 10 2012
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 1203 PM MDT WED OCT 10 2012
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOW SIMILAR PATTERN AS THE
LAST FEW DAYS...WITH BROAD TROUGH ACROSS CANADA EXTENDING SOUTH
ACROSS THE EASTERN US. A REX BLOCK IS ALSO STILL IN PLACE OFF THE
WESTERN US...WITH A CLOSED UPPER LOW BEGINNING TO MOVE OVER THE
CENTRAL CALIFORNIA COAST. A SHORTWAVE RIDGE EXTENDS NORTH OVER
WESTERN COLORADO AND TOWARDS THE GREAT BASIN. AT THE SURFACE HIGH
PRESSURE EXTENDS FROM THE CENTRAL MISSISSIPPI VALLEY WEST INTO
CENTRAL KANSAS. A LEE TROUGH IS DEEPENING OVER EASTERN
COLORADO...WITH INCREASING PRESSURE GRADIENT OVER WESTERN KS BETWEEN
THESE FEATURES.
GOOD WAA OVERNIGHT TONIGHT...COMBINED WITH MID-HIGH CLOUD COVER
COMPLICATES THE LOW TEMPERATURE. WINDS SHOULD DIMINISH AROUND
SUNSET AS DAYTIME HEATING COMES TO AN END...AND THE LEE TROUGH
AXIS SHIFTS EAST OVER THE CWA...SO WINDS SHOULD NOT BE AS MUCH OF
AN ISSUE. TEMPERATURES CURRENTLY EXPECTED TO BE IN THE 40S ACROSS
MOST OF THE AREA. IF CLOUD COVER WERE TO BE MORE EXTENSIVE WE
MAY SEE OVERNIGHT TEMPS CLOSER TO 50F AT SOME LOCATIONS.
A COLD FRONT WILL PUSH SOUTH OVER THE CWA AS A SHORTWAVE TROUGH
MOVES FROM SOUTHERN CANADA INTO NORTHERN MINNESOTA THURSDAY. WITH
VERY LITTLE IN MOISTURE IN PLACE AND BEST LARGE SCALE ASCENT WELL TO
THE NORTH AND EAST...NO PRECIP IS EXPECTED. LATEST GUIDANCE FAVORS
FRONTAL PASSAGE AROUND 15Z ACROSS MOST OF THE CWA...AND AROUND 18Z
ACROSS THE SOUTHERN HALF OF THE CWA. I HAVE TRENDED TEMPS DOWN
ACCORDINGLY...WITH HIGHS IN THE UPPER 50S/LOW 60S ACROSS THE
NORTH...AND NEAR 70 ACROSS THE SOUTH.
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 250 AM MDT WED OCT 10 2012
A RATHER POTENT UPPER LEVEL CLOSED LOW WILL MOVE ACROSS NORTHEASTERN
COLORADO AND UP THROUGH WESTERN NEBRASKA SATURDAY. RAPID
CYCLOGENESIS WILL OCCUR AS IT MOVES INTO THE CENTRAL HIGH PLAINS
CAPE AXIS WILL EXTEND THROUGH TEXAS AND UP INTO CENTRAL NEBRASKA
EARLY SATURDAY MORNING AND ACROSS EASTERN KANSAS AND NEBRASKA
LATER ON...SETTING THE STAGE FOR SEVERE WEATHER ACROSS PORTIONS OF
KANSAS AND NEBRASKA LATER IN THE DAY. DRY SLOT LOOKS TO DEVELOP
ACROSS CWA BY EARLY AFTERNOON WITH THE SYSTEM COMPLETELY CLEARED
OUT BY EARLY EVENING AS THE TROUGH QUICKLY LIFTS INTO THE UPPER
MISSOURI RIVER VALLEY. THE SYSTEM DOES NOT LOOK OVERLY COLD AND
TEMPERATURES WILL QUICKLY BOUNCE BACK INTO THE 70S BY SUNDAY
AFTERNOON. AS THE TROUGH CONTINUES TO MOVE TOWARDS NEW ENGLAND...A
RIDGE WILL BUILD INTO THE WESTERN STATES PUTTING THE HIGH PLAINS
UNDER NORTHWEST FLOW ALOFT. THIS WILL ALLOW FOR MILD TEMPERATURES
AND DRY CONDITIONS INTO EARLY NEXT WEEK.
THE NEXT COLD FRONT WILL MOVE ACROSS THE REGION TUESDAY AS THE
ASSOCIATED SHORTWAVE TROUGH MOVES ACROSS THE PLAINS.
ATTM...PRECIPITATION CHANCES LOOK TO REMAIN WELL NORTH OF THE AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1124 AM MDT WED OCT 10 2012
VFR CONDITIONS WILL CONTINUE THROUGH THE PERIOD AT BOTH KGLD AND
MCK TERMINALS. SOUTH WINDS 15 TO 20 KTS ARE EXPECTED AT BOTH
TERMINALS THROUGH THIS AFTERNOON...WITH GUSTS AROUND 30 KTS. THESE
WINDS WILL DECREASE AROUND SUNSET AND BECOME LIGHT AND VARIABLE AS
THE SURFACE TROUGH OVER EASTERN COLORADO SHIFTS EAST. WINDS WILL
SHIFT TO THE NORTH AND INCREASE BETWEEN 14-15Z THURSDAY AS A COLD
FRONT DROPS SOUTH OVER BOTH TERMINALS. WIND GUSTS AROUND 25 KTS
ARE EXPECTED IMMEDIATELY BEHIND THE FRONT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...PMM
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1148 PM MDT TUE OCT 9 2012
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 233 PM MDT TUE OCT 9 2012
EARLY AFTERNOON WV IMAGERY AND RUC H5 ANALYSIS SHOW BROAD TROUGH IN
STILL IN PLACE ACROSS THE US. A POSITIVELY TILTED LONGWAVE TROUGH
AXIS CURRENTLY EXTENDS SOUTHWEST ALONG THE UPPER MISSISSIPPI VALLEY
ACROSS CENTRAL KANSAS. REX BLOCK IS STILL IN PLACE OFF THE
WESTERN...WITH ASSOCIATED CLOSED LOW CENTERED JUST OFF THE
CALIFORNIA COAST. AT THE SURFACE HIGH PRESSURE IS CURRENTLY IN PLACE
ACROSS THE NORTHERN AND HIGH PLAINS REGIONS BEHIND A COLD FRONT THAT
MOVED THROUGH WESTERN KANSAS THIS MORNING.
SKIES SHOULD CLEAR ACROSS THE CWA AS STRATUS ACROSS THE WESTERN
CWA SHIFTS WEST AND DISSIPATES. THE REMAINDER OF THE NIGHT SHOULD
BE MOSTLY CLEAR WITH ONLY PASSING HIGH CLOUDS. THERE IS SOME
INDICATION OF STRATUS/FOG DEVELOPMENT OVER EASTERN
COLORADO...HOWEVER THIS LOOKS TO REMAIN JUST WEST OF OUR CWA...SO
NO MENTION IS INCLUDED IN THE FORECAST AT THIS TIME.
WINDS WILL DECREASE LATE THIS AFTERNOON AND EARLY THIS EVENING AS
HIGH PRESSURE CONTINUES TO BUILD SOUTH. WITH A COOL AIRMASS IN PLACE
MOST OF THE CWA SHOULD SEE TEMPS DROP TO THE 30-35F RANGE...WITH THE
COLDEST TEMPS IN THE EAST. WINDS WILL INCREASE FROM THE SOUTHWEST IN
THE WEST TOWARDS SUNRISE...WHICH WILL ALSO HELP BRING TEMPS BACK UP
ABOVE FREEZING. DESPITE THIS...THERE IS STILL A WINDOW IN THE WEST
BETWEEN 06-09Z WHEN MANY LOCATIONS WILL BE WITHIN FROST ADVISORY
CRITERIA. LOCATIONS NORTH AND EAST HAVE ALREADY SEEN A HARD
FREEZE...SO I ONLY ISSUED A FROST ADVISORY FOR THE SOUTHWEST
QUADRANT OF MY CWA.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 233 PM MDT TUE OCT 9 2012
UPPER FLOW WILL BE NORTHWEST WEDNESDAY NIGHT TRANSITIONING TO A MORE
WESTERLY FLOW AS A RIDGE BUILDS INTO THE CENTRAL ROCKIES ON
THURSDAY. FLOW BECOMES SOUTHWESTERLY THURSDAY NIGHT AHEAD OF AN
UPPER THAT MOVES TO A POSITION WEST OF THE FOUR CORNERS REGION
FRIDAY. SURFACE HIGH PRESSURE WILL CONTINUE OVER THE CENTRAL PLAINS
WEDNESDAY NIGHT. LOW PRESSURE WILL MOVE INTO EASTERN COLORADO
THURSDAY. A COLD FRONT WILL MOVE INTO NORTHWEST KANSAS THURSDAY
AFTERNOON/NIGHT FOLLOWED BY HIGH PRESSURE FRIDAY.
DRY CONDITIONS WILL CONTINUE THROUGH THURSDAY WITH LACK OF FORCING
AND MOISTURE. LATE THURSDAY NIGHT/EARLY FRIDAY MORNING DYNAMICS
APPROACH THE FA FROM THE SOUTHWEST. PLAN TO KEEP A SMALL AREA OF
SLIGHT CHANCE/CHANCE POPS ACROSS THE EXTREME SOUTHERN FA.
PRECIPITATION APPEARS MORE LIKELY FRIDAY SO HAVE INCREASED POPS TO
HIGHER CHANCE POPS.
MIN TEMPERATURES WILL RANGE FROM THE LOWER 40S WEDNESDAY NIGHT
COOLING TO THE UPPER 30S THURSDAY NIGHT. MAX TEMPERATURES THURSDAY
WILL BE AROUND 70. CLOUDS AND PRECIPITATION WILL KEEP HIGH
TEMPERATURES FRIDAY IN THE UPPER 50S
FOR FRIDAY NIGHT THROUGH MONDAY...THE UPPER TROUGH WILL BE OVER THE
CENTRAL ROCKIES FRIDAY NIGHT AND LIFT NORTHEAST INTO NORTHCENTRAL
NEBRASKA SATURDAY. NORTHWEST FLOW WILL RESUME SUNDAY AND CONTINUE
THROUGH TUESDAY. A SURFACE TROUGH WILL BE OVER EASTERN COLORADO
FRIDAY NIGHT. THIS AREA OF LOW PRESSURE WILL MOVE INTO NORTHEAST
NEBRASKA SATURDAY FOLLOWED BY HIGH PRESSURE SATURDAY NIGHT AND
SUNDAY. ANOTHER TROUGH WILL DEVELOP IN EASTERN COLORADO MONDAY
REPLACED BY HIGH PRESSURE TUESDAY.
GOOD DYNAMICS AND MOISTURE WILL SUPPORT HIGH CHANCE AND LIKELY POPS
FRIDAY NIGHT. PRECIPITATION CHANCES LOWER TO SLIGHT CHANCE OVER THE
FAR NORTHWEST FA SATURDAY AS THE SYSTEM MOVES INTO NEBRASKA.
SUBSIDENCE MOVES IN BEHIND THIS SYSTEM. POPS WILL BE NIL FROM
SATURDAY THROUGH TUESDAY. MIN TEMPERATURES WILL BE IN THE MID 40S
FOR THIS PART OF THE FORECAST. MAX TEMPERATURES WILL RISE TO AROUND
70 EACH DAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1134 PM MDT TUE OCT 9 2012
VFR CONDITIONS WILL PREVAIL ACROSS THE CENTRAL HIGH PLAINS REGION
THROUGH THE TAF PERIOD. WINDS WILL START OUT LIGHT AND VARIABLE
AND TURN MORE SOUTHWESTERLY BETWEEN 09-12Z AS THE SURFACE HIGH
CENTER MOVES FURTHER INTO THE PLAINS SATES. SOUTHWEST WIND WILL
INCREASE AND BECOME GUSTY AS THE SURFACE PRESSURE GRADIENT
INCREASES THROUGH THE DAY WITH THE APPROACHING SURFACE TROUGH.
WINDS WILL SLACKEN SOMEWHAT AND TURN MORE SOUTHERLY AFTER 00Z AS
THE OVERNIGHT INVERSION SETS UP AND HIGH CLOUDS BEGIN TO STREAM
ACROSS THE REGION.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...FROST ADVISORY UNTIL 9 AM MDT /10 AM CDT/ WEDNESDAY FOR KSZ013-
014-027-028-041-042.
CO...FROST ADVISORY UNTIL 9 AM MDT WEDNESDAY FOR COZ091-092.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...FS
AVIATION...LOCKHART
AREA FORECAST DISCUSSION
NWS JACKSON KY
915 PM EDT THU OCT 11 2012
.UPDATE...
ISSUED AT 915 PM EDT THU OCT 11 2012
UPDATED FORECAST TO REMOVE THUNDER CHANCES. MODELS ARE REALLY LACKING
ANY INSTABILITY TONIGHT. THUS...DO NOT SEE ANY SUPPORT FOR THUNDER.
AS FAR AS THE FROST POTENTIAL...COOP MOS GUIDANCE HAS THE COLDEST
OVERNIGHT LOW AT 36 WHICH IS PROBABLY THE ABSOLUTE MINIMUM
TEMPERATURES COULD REACH TONIGHT GIVEN THE INCREASING CLOUD COVER
LATE. THUS...GOING TO REMOVE THE MENTION OF FROST. AS FAR AS
PRECIPITATION CHANCES...THE RUC AND HRRR ARE BOTH INDICATING
SCATTERED SHOWERS SPREADING INTO OUR SOUTHWEST TOWARDS DAWN.
THUS...PLAN TO BRING THE CHANCE OF RAIN UP TO BETWEEN 30 AND 40
PERCENT. IT LOOKS LIKE THE THREAT FOR RAIN WILL BE SHORT LIVED AND
WILL BE ON THE WAY OUT BY MID MORNING. THE ZFP...HWO AND NDFD HAVE
ALREADY BEEN UPDATED.
UPDATE ISSUED AT 729 PM EDT THU OCT 11 2012
STILL A BIT OF UNCERTAINTY WITH EXACTLY HOW MUCH AREAL COVERAGE THERE
WILL BE TONIGHT. LATEST HRRR (20Z) SHOWS A BIT MORE PRECIPITATION
COMING ACROSS OUR SOUTHWEST ZONES AFTER 08Z. HOWEVER...PREVIOUS RUNS
HAD ALMOST NOTHING. IT WILL BE INTERESTING TO SEE IF THE NEW RUN OF
THE HRRR TAKES HOLD OR IF IT BACKS OFF WITH THE NEXT RUN.
REGARDLESS...GOING TO BE WATCHING THINGS UPSTREAM AS CONVECTION IS
EXPECTED TO DEVELOP ACROSS SOUTHERN MISSOURI AND WESTERN
KENTUCKY...THEN SPREAD INTO THE AREA LATE. IF THE CONVECTION DOES NOT
MATERIALIZE...THIS WOULD OBVIOUSLY LEND ITSELF TO A DRIER FORECAST.
ITS GOING TO BE A WAITING GAME OVER THE NEXT 3 TO 5 HOURS. BASED ON
THE LACK OF SIGNIFICANT FORCING AND PRESENT ACTIVITY UPSTREAM...MY
GUT FEELING IS THAT WE WILL PROBABLY END UP ON THE DRIER SIDE OF
THINGS. HOWEVER...PLAN TO WAIT THINGS OUT AND PERHAPS SEE WHAT SOME
OF THE NEW 00Z MODELS COME IN WITH. FOR NOW...MADE SIGNIFICANT HOURLY
TWEAKS TO TEMPERATURES AND DEWPOINTS TO REPRESENT THE QUICKLY FALLING
VALLEY TEMPS THIS EVENING. PLAN TO REWORK TEMPERATURES FURTHER TO
SHOW MORE STEADY OR SLOWLY FALLING TEMPS IN THE SOUTHWEST WITH THE
INCREASING CLOUD COVER. GRIDS HAVE BEEN SAVED AND SENT TO NDFD.
&&
.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 322 PM EDT THU OCT 11 2012
A WARM FRONT WILL APPROACH FROM THE SOUTHWEST WHILE A WEAKENING COLD
FRONT ENTERS THE REGION FROM THE NORTHWEST LATE TONIGHT. ELEVATED
WARM AIR ADVECTION NORTH OF THE WARM FRONT IS FORECAST TO PRODUCE A
SATURATED WARM LAYER AROUND 800-850 MB OVER OUR SW COUNTIES LATE
TONIGHT AND FRIDAY MORNING...RESULTING IN INCREASING CLOUDS. FORECAST
SOUNDINGS SHOW A CONVECTIVE CAP OVER TOP OF THIS LAYER ACROSS MOST OF
THE FORECAST AREA. HOWEVER...THERE IS ONLY A THIN CAP AROUND 650 MB
AT 12Z FRIDAY IN OUR FAR SW...AND WILL CONTINUE TO USE 20 PERCENT
POPS FOR TSRA THERE LATE TONIGHT AND EARLY FRIDAY.
DRIER AIR WILL WORK IN FROM THE NORTH BEHIND THE DECAYING COLD FRONT
DURING THE DAY FRIDAY AND BRING A RETURN TO CLEAR SKIES FOR MOST OF
FRIDAY NIGHT...AS SURFACE HIGH PRESSURE CONTROLLING OUR WEATHER
PASSES BY TO OUR NE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 322 PM EDT THU OCT 11 2012
AN ACTIVE AND SOMEWHAT PROGRESSIVE PATTERN LOOKS TO BE IN PLACE FOR
THE EXTENDED PERIOD. THE UPPER LEVEL PATTERN THROUGH THE EARLY PART
OF THE EXTENDED IS HIGHLIGHTED BY A BROAD TROUGH OVER THE UPPER
GREAT LAKES WITH SUCCESSIVE SHORTWAVES MOVING THROUGH THE NORTHERN
PLAINS AND INTO THE GREATER LAKES. BY SUNDAY...THE BROAD TROUGH OVER
THE GREAT LAKES FINALLY SHIFTS EAST INTO THE ATLANTIC AS THE NEXT
WAVE MOVES THROUGH THE PLAINS INTO THE UPPER MS VALLEY. RECENT RUNS
OF THIS WAVE HAVE SHOWN A GENERAL INCREASE IN STRENGTH AS THE RECENT
RUN OF THE GFS SHOWS A NEGATIVELY TILTED TROUGH MOVING INTO THE OHIO
VALLEY SUNDAY EVENING. GIVEN THE FLOW...WILL WAIT FOR SOME LATER
RUNS TO GAUGE THE LEVEL OF CONVECTION AS RIGHT NOW...INSTABILITY
LOOKS TO BE IN QUESTION. 12Z RUNS ALONG WITH THE ALL BLEND ARE
COMING IN WITH A BIT OF INSTABILITY SO WILL THROW IN CHANCE THUNDER
FOR SUNDAY.
BY MONDAY NIGHT...HIGH PRESSURE FILTERS IN BEHIND THE FRONT WITH
ANOTHER EARLY FALL LIKE AIR MASS POISED TO ADVECT IN. HOWEVER...THE
PATTERN SUGGESTS THE FRONT TO SLOW OVER THE APPALACHIAN CHAIN FOR
MONDAY NIGHT AND INTO TUESDAY. THIS COULD SLOW THE IMPACT OF THE AIR
MASS BEHIND THE FRONT AND KEEP TEMPS FROM BOTTOMING OUT AT THE
SURFACE. WILL ADDRESS THESE FORECAST PROBLEMS BASED ON THE ALL
MODELS BLEND SOLUTION. ALSO WILL KEEP CLOUD COVER LINGERING IN THE
EASTERN RANGES THROUGH MONDAY NIGHT AS THE FRONT WILL LIKELY HANG UP
ALONG THE APPALACHIAN RANGE.
HIGH PRESSURE WILL SETTLE FINALLY BY TUESDAY BEFORE THE NEXT WAVE
BEGINS TO IMPACT THE AREA LATE WEDNESDAY. THE SOMEWHAT PROGRESSIVE
PATTERN IN THE EXTENDED AND LACK OF AMPLITUDE WILL LEAD TO MORE
SEASONAL LOWS FOR EASTERN KENTUCKY IN THE MID TO UPPER 40S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 729 PM EDT THU OCT 11 2012
VFR CONDITIONS WILL CONTINUE OVER THE NEXT 24 HOURS. THE ONLY CHANCE
TO TEMPORARILY GO TO MVFR WILL BE AROUND DAYBREAK...AS CIGS LOWER TO
AROUND 3.5KFT. THIS CIGS COULD TEMPORARILY DROP SLIGHTLY UNDER
3KFT...BUT TOO MUCH UNCERTAINTY TO GO THAT LOW AT THIS TIME.
OTHERWISE...CIG HEIGHTS WILL AGAIN BE ON THE INCREASE TOMORROW BEFORE
SKIES CLEAR FROM THE NORTH IN THE AFTERNOON AND EVENING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...HAL
LONG TERM...SHALLENBERGER
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
729 PM EDT THU OCT 11 2012
.UPDATE...
ISSUED AT 729 PM EDT THU OCT 11 2012
STILL A BIT OF UNCERTAINTY WITH EXACTLY HOW MUCH AREAL COVERAGE THERE
WILL BE TONIGHT. LATEST HRRR (20Z) SHOWS A BIT MORE PRECIPITATION
COMING ACROSS OUR SOUTHWEST ZONES AFTER 08Z. HOWEVER...PREVIOUS RUNS
HAD ALMOST NOTHING. IT WILL BE INTERESTING TO SEE IF THE NEW RUN OF
THE HRRR TAKES HOLD OR IF IT BACKS OFF WITH THE NEXT RUN.
REGARDLESS...GOING TO BE WATCHING THINGS UPSTREAM AS CONVECTION IS
EXPECTED TO DEVELOP ACROSS SOUTHERN MISSOURI AND WESTERN
KENTUCKY...THEN SPREAD INTO THE AREA LATE. IF THE CONVECTION DOES NOT
MATERIALIZE...THIS WOULD OBVIOUSLY LEND ITSELF TO A DRIER FORECAST.
ITS GOING TO BE A WAITING GAME OVER THE NEXT 3 TO 5 HOURS. BASED ON
THE LACK OF SIGNIFICANT FORCING AND PRESENT ACTIVITY UPSTREAM...MY
GUT FEELING IS THAT WE WILL PROBABLY END UP ON THE DRIER SIDE OF
THINGS. HOWEVER...PLAN TO WAIT THINGS OUT AND PERHAPS SEE WHAT SOME
OF THE NEW 00Z MODELS COME IN WITH. FOR NOW...MADE SIGNIFICANT HOURLY
TWEAKS TO TEMPERATURES AND DEWPOINTS TO REPRESENT THE QUICKLY FALLING
VALLEY TEMPS THIS EVENING. PLAN TO REWORK TEMPERATURES FURTHER TO
SHOW MORE STEADY OR SLOWLY FALLING TEMPS IN THE SOUTHWEST WITH THE
INCREASING CLOUD COVER. GRIDS HAVE BEEN SAVED AND SENT TO NDFD.
&&
.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 322 PM EDT THU OCT 11 2012
A WARM FRONT WILL APPROACH FROM THE SOUTHWEST WHILE A WEAKENING COLD
FRONT ENTERS THE REGION FROM THE NORTHWEST LATE TONIGHT. ELEVATED
WARM AIR ADVECTION NORTH OF THE WARM FRONT IS FORECAST TO PRODUCE A
SATURATED WARM LAYER AROUND 800-850 MB OVER OUR SW COUNTIES LATE
TONIGHT AND FRIDAY MORNING...RESULTING IN INCREASING CLOUDS. FORECAST
SOUNDINGS SHOW A CONVECTIVE CAP OVER TOP OF THIS LAYER ACROSS MOST OF
THE FORECAST AREA. HOWEVER...THERE IS ONLY A THIN CAP AROUND 650 MB
AT 12Z FRIDAY IN OUR FAR SW...AND WILL CONTINUE TO USE 20 PERCENT
POPS FOR TSRA THERE LATE TONIGHT AND EARLY FRIDAY.
DRIER AIR WILL WORK IN FROM THE NORTH BEHIND THE DECAYING COLD FRONT
DURING THE DAY FRIDAY AND BRING A RETURN TO CLEAR SKIES FOR MOST OF
FRIDAY NIGHT...AS SURFACE HIGH PRESSURE CONTROLLING OUR WEATHER
PASSES BY TO OUR NE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 322 PM EDT THU OCT 11 2012
AN ACTIVE AND SOMEWHAT PROGRESSIVE PATTERN LOOKS TO BE IN PLACE FOR
THE EXTENDED PERIOD. THE UPPER LEVEL PATTERN THROUGH THE EARLY PART
OF THE EXTENDED IS HIGHLIGHTED BY A BROAD TROUGH OVER THE UPPER
GREAT LAKES WITH SUCCESSIVE SHORTWAVES MOVING THROUGH THE NORTHERN
PLAINS AND INTO THE GREATER LAKES. BY SUNDAY...THE BROAD TROUGH OVER
THE GREAT LAKES FINALLY SHIFTS EAST INTO THE ATLANTIC AS THE NEXT
WAVE MOVES THROUGH THE PLAINS INTO THE UPPER MS VALLEY. RECENT RUNS
OF THIS WAVE HAVE SHOWN A GENERAL INCREASE IN STRENGTH AS THE RECENT
RUN OF THE GFS SHOWS A NEGATIVELY TILTED TROUGH MOVING INTO THE OHIO
VALLEY SUNDAY EVENING. GIVEN THE FLOW...WILL WAIT FOR SOME LATER
RUNS TO GAUGE THE LEVEL OF CONVECTION AS RIGHT NOW...INSTABILITY
LOOKS TO BE IN QUESTION. 12Z RUNS ALONG WITH THE ALL BLEND ARE
COMING IN WITH A BIT OF INSTABILITY SO WILL THROW IN CHANCE THUNDER
FOR SUNDAY.
BY MONDAY NIGHT...HIGH PRESSURE FILTERS IN BEHIND THE FRONT WITH
ANOTHER EARLY FALL LIKE AIR MASS POISED TO ADVECT IN. HOWEVER...THE
PATTERN SUGGESTS THE FRONT TO SLOW OVER THE APPALACHIAN CHAIN FOR
MONDAY NIGHT AND INTO TUESDAY. THIS COULD SLOW THE IMPACT OF THE AIR
MASS BEHIND THE FRONT AND KEEP TEMPS FROM BOTTOMING OUT AT THE
SURFACE. WILL ADDRESS THESE FORECAST PROBLEMS BASED ON THE ALL
MODELS BLEND SOLUTION. ALSO WILL KEEP CLOUD COVER LINGERING IN THE
EASTERN RANGES THROUGH MONDAY NIGHT AS THE FRONT WILL LIKELY HANG UP
ALONG THE APPALACHIAN RANGE.
HIGH PRESSURE WILL SETTLE FINALLY BY TUESDAY BEFORE THE NEXT WAVE
BEGINS TO IMPACT THE AREA LATE WEDNESDAY. THE SOMEWHAT PROGRESSIVE
PATTERN IN THE EXTENDED AND LACK OF AMPLITUDE WILL LEAD TO MORE
SEASONAL LOWS FOR EASTERN KENTUCKY IN THE MID TO UPPER 40S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 729 PM EDT THU OCT 11 2012
VFR CONDITIONS WILL CONTINUE OVER THE NEXT 24 HOURS. THE ONLY CHANCE
TO TEMPORARILY GO TO MVFR WILL BE AROUND DAYBREAK...AS CIGS LOWER TO
AROUND 3.5KFT. THIS CIGS COULD TEMPORARILY DROP SLIGHTLY UNDER
3KFT...BUT TOO MUCH UNCERTAINTY TO GO THAT LOW AT THIS TIME.
OTHERWISE...CIG HEIGHTS WILL AGAIN BE ON THE INCREASE TOMORROW BEFORE
SKIES CLEAR FROM THE NORTH IN THE AFTERNOON AND EVENING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...HAL
LONG TERM...SHALLENBERGER
AVIATION...KAS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
800 AM EDT WED OCT 10 2012
.UPDATE...
ISSUED AT 635 AM EDT WED OCT 10 2012
UPDATED THE FORECAST TO REFLECT THE MULTI-LAYER OF CLOUDS THAT HAVE
SPREAD INTO...AND DEVELOPED OVER...EAST KENTUCKY EARLY THIS MORNING.
ALSO EXPANDED THE SPRINKLES THROUGH 8 AM FOR FAR SOUTHEAST PARTS OF
THE CWA. OTHERWISE...TOOK THIS OPPORTUNITY TO TWEAK THE HOURLY T
AND TD GRIDS WITH RESPECT TO THE CURRENT CONDITIONS AND TRENDS.
UPDATES HAVE BEEN SENT TO THE WEB AND NDFD SERVERS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 340 AM EDT WED OCT 10 2012
...FROST ADVISORY AND A NW FREEZE WARNING TONIGHT...
06Z SFC ANALYSIS SHOWS A COLD FRONT...EXTENDING FROM A LOW CENTERED
NORTH OF MICHIGAN...ENTERING THE STATE OF KENTUCKY. THIS BOUNDARY IS
MAINLY A DRY ONE ATTM WITH JUST SOME LIGHT RAIN/SPRINKLES SHOWING UP
ON RADAR OVER CENTRAL AND NORTHERN INDIANA ALONG WITH SOME TO THE
EAST OF THE FRONT MOVING THROUGH NORTH CENTRAL TENNESSEE. A
SMATTERING OF LOW CLOUDS REMAIN OVER FAR EASTERN KENTUCKY...BUT FOR
THE MOST PART SKIES ARE CLEAR. THIS HAS ALLOWED THE VALLEYS TO DROP
OFF INTO THE UPPER 30S IN MANY CASE WHILE THE RIDGES HOLD IN THE LOWER
AND MIDDLE 40S. PATCHY FOG IS ALSO NOTED IN THE DEEPER VALLEYS OF THE
EAST. THIS WILL ALL CLEAR OUT TOWARD DAWN AS THE CLOUDS OF THE FRONT
MOVES IN ALONG WITH A STIRRING OF THE WIND FROM THE SOUTH. THE PICK
UP IN WINDS SHOULD ALSO MIX THE AIR MORE EFFECTIVELY AND ALLOW VALLEY
TEMPS TO RISE TOWARD DAWN.
THE MODELS REMAIN IN GOOD AGREEMENT ALOFT WITH THE TROUGH SWINGING
THROUGH THE GREAT LAKES AND OHIO VALLEY TODAY. THIS TROUGH AND ITS
EFFECTS WILL LIFT OUT OF THE REGION QUICKLY LATER TODAY AND SET UP A
REGIME OF SLOWLY RISING HEIGHTS...BUT ALSO FAST AND SLIGHTLY
NORTHWEST FLOW OVER THE AREA INTO THURSDAY EVENING.
THE MODEL DIFFERENCES...SLIGHT THAT THEY ARE...IN SENSIBLE WEATHER
WITH THIS SYSTEM REVOLVE PRIMARILY AROUND THE RESOLUTION AND INTERNAL
MECHANICS OF THE MODELS THEMSELVES. ACCORDINGLY...THE HIGHER
RESOLUTION HRRR AND DOWNSCALE NAMDNG SHOW ENOUGH OOMPH WITH THIS
FRONT TO PRINT OUT SMALL POPS LATER THIS MORNING AND INTO EARLY
AFTERNOON. MEANWHILE ALL THE OTHER MODELS...ASIDE FROM THE ECMWF...
ARE DRY...INCLUDING THE RUC13. PLAN ON FOLLOWING THE IDEAS OF THE
HRRR WITH SOME ECMWF SUPPORT FOR POPS TODAY. AS THERE ARE SOME SIGNS
OF PCPN SHOWING UP ON RADAR ALONG THIS BOUNDARY ATTM...SOME EXTRA
LIFT AVAILABLE COMING THROUGH THE HIGHER TERRAIN HERE...AND DECENT
DYNAMICS TO THE NORTH WILL CONTINUE A SMALL CHANCE/ISOLATED POPS
SCENARIO FOR EAST KENTUCKY TODAY...BUT CERTAINLY THE MAJORITY OF THE
AREA WILL STAY DRY. THE CLOUDS AND ANY LIGHT PCPN FROM THIS BOUNDARY
WILL MOVE OUT BY EVENING AND ALLOW FOR A CHILLY NIGHT...ESPECIALLY
ONCE THE WINDS GO LIGHT AND CALM AFTER SUNSET.
THE CLEARING SKIES AND LIGHT WINDS WILL SET THE STAGE FOR THE
COLDEST NIGHT...ACROSS ALL OF EAST KENTUCKY...OF THE YOUNG FALL
SEASON WITH WIDESPREAD AND POTENTIALLY RATHER THICK FROST A GOOD BET.
THE FROST ON TUESDAY MORNING ONLY REALLY AFFECTED LOCALIZED AREAS TO
OUR NORTHWEST WHILE FOG MANAGED TO PROTECT THE COLDER SPOTS IN THE
WESTERN PORTION OF THE CUMBERLAND VALLEY. THEREFORE FOR THE MAJORITY
OF EAST KENTUCKY FROST WILL BE THE LARGER THREAT TONIGHT AS
TEMPERATURES ARE ONLY EXPECTED TO DIP DOWN JUST BELOW FREEZING IN
ABOUT HALF THE AREA AND FOR A JUST BRIEF PERIOD TOWARDS DAWN. AS A
RESULT...WILL ISSUE A FREEZE WARNING IN THE NORTHWEST THAT SAW MORE
FROST YESTERDAY MORNING AND KICK OFF A FROST ADVISORY OVER THE REST
OF THE CWA. WILL START THESE AT MIDNIGHT AS THE DEEPER VALLEYS SHOULD
DROP OFF FAST FOLLOWING SUNSET AND A SETTLING OF THE WINDS.
HOWEVER...FREEZING TEMPERATURES WILL NOT OCCUR UNTIL CLOSER TOWARD
DAWN OVER THE NORTHWEST...BUT WIDESPREAD FROST CAN BE EXPECTED MUCH
EARLIER IN THE NIGHT. TO EASE ANY CONFUSION WITH THE TWO
FROST/FREEZE HEADLINES FOR OUR AREA...BUT VERY SIMILAR EFFECTS
EXPECTED...WILL ISSUE THEM FOR THE SAME VALID TIMES FROM MIDNIGHT
THROUGH 9 AM EDT. THURSDAY WILL BE A NICE DAY AFTER A CHILLY START
WITH PLENTY OF SUNSHINE AND ONLY A SMALL INCREASE IN CLOUDS FROM THE
WEST LATE IN THE DAY.
HAVE FOLLOWED A MIX OF THE INHERITED GRIDS...MAV GUIDANCE...AND
TERRAIN BASED EDITING FOR THE TEMPERATURES TONIGHT AND OTHERWISE. AS
FOR POPS...AGAIN RAN HIGHER THAN THE GUIDANCE FOR TODAY/S SLIGHT
CHANCES.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 355 AM EDT WED OCT 10 2012
THE FIRST ISSUE TO CONTEND WITH IN THE EXTENDED CENTERS AROUND A
SHORT WAVE CURRENTLY DROPPING SOUTH OUT OF THE FRONT RANGE OF THE
CANADIAN ROCKIES...WITH AN ASSOCIATED SFC LOW TAKING SHAPE ALONG THE
U.S./CANADIAN BORDER. MODELS REMAIN IN RELATIVELY GOOD AGREEMENT
WITH THIS DUO...BRINGING THEIR ASSOCIATED ENERGY INTO THE GREAT
LAKES LATE THURSDAY INTO FRIDAY MORNING.
HIGH PRESSURE BUILDING OVER THE COMMONWEALTH TODAY WILL BE SHIFTING
TO THE EAST BY TOMORROW NIGHT...INVOKING SOUTHERLY RETURN FLOW BACK
INTO THE AREA AHEAD OF A COLD FRONT ASSOCIATED WITH THE SFC LOW AS
IT TREKS THROUGH THE GREAT LAKES. MOISTURE PROFILES ARE LOOKING A
LITTLE BETTER THIS MORNING...AND HAVE BOOSTED POPS A BIT ACROSS THE
BOARD FOR THURSDAY NIGHT AND FRIDAY MORNING. INSTABILITY STILL DOES
NOT LOOK ALL THAT IMPRESSIVE...BUT WILL CONTINUE TO ADVERTISE
THUNDER THROUGH THIS WINDOW. HOWEVER...ATTM...IT WOULD APPEAR THAT
ANY TSTMS WOULD BE ISOLATED AND WELL BELOW SEVERE THRESHOLDS.
HIGH PRESSURE LOOKS TO TRAVERSE THE GREAT LAKES FRIDAY NIGHT THROUGH
SATURDAY IN CONJUNCTION WITH SHORT WAVE RIDGING OVERHEAD YIELDING
QUIETER WEATHER TO START THE WEEKEND. DURING THIS TIME...A CUTOFF
LOW STILL PARKED OFF THE COAST OF CA IS EXPECTED TO DIG INTO THE
DESERT SW BEFORE EVOLVING INTO MORE OF AN OPEN WAVE AS IT LIFTS
ACROSS THE PLAINS. MODELS REMAIN IN GOOD AGREEMENT WITH BRINGING
THIS FEATURE INTO THE GREAT LAKES SATURDAY NIGHT INTO SUNDAY WITH
THE ACCOMPANYING SFC REFLECTION USHERING AN ASSOCIATED COLD FRONT
INTO THE OHIO VALLEY.
ABOUT THIS TIME...MODELS BEGIN TO DIVERGE WITH THE EVOLUTION OF THE
UPPER LEVEL PATTERN. A VERY LOOSE CONSENSUS THIS MORNING SUGGESTS
SOME STALLING OF THE COLD FRONT AS IT MOVES INTO ERN KY WITH THE
PARENT UPPER LEVEL TROF PAUSING OVER THE LENGTH OF THE MS VALLEY
WHILE A SECONDARY SHORT WAVE DROPS DOWN THE BACKSIDE...DEEPENING THE
UPPER TROF BEFORE ULTIMATELY KICKING THE FRONT AND THE BULK OF ANY
LINGERING PRECIP TO THE EAST OF THE AREA BY LATE IN THE DAY MONDAY.
THEREAFTER...A SOLID CONSENSUS BECOMES NEARLY IMPOSSIBLE TO COME BY.
WITH MUCH UNCERTAINTY THIS FAR OUT...HAVE OPTED TO KEEP POPS LIMITED
TO 20 PERCENT OR LESS THROUGH THE MIDDLE OF NEXT WEEK UNTIL BETTER
MODEL AGREEMENT CAN BE ACHIEVED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 800 AM EDT WED OCT 10 2012
MID AND LOW LEVEL CLOUDS HAVE PUSHED OVER THE FORECAST AREA FROM THE
WEST AS A MAINLY DRY COLD FRONT APPROACHES. THESE CLOUDS AND THE ODD
CHANCE OF A SHOWER OR SPRINKLE WILL BE THE MAIN EFFECTS OF THE FRONT
AND WILL EXIT WEST TO EAST DURING THE AFTERNOON AND EVENING. ALSO...
THERE WILL BE A SOLID WIND SHIFT WITH THE FRONT. LIGHT SOUTHWEST
WINDS WILL BECOME WESTERLY AND PICK UP A NOTCH JUST AHEAD OF THE
FRONT DURING THE DAY WITH WINDS BECOMING MORE WESTERLY AND STAYING
UP BEHIND THE BOUNDARY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM EDT THURSDAY FOR
KYZ044-050>052-058>060-104.
FROST ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EDT THURSDAY FOR
KYZ068-069-079-080-083>088-106>120.
&&
$$
UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM....MB
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
635 AM EDT WED OCT 10 2012
.UPDATE...
ISSUED AT 635 AM EDT WED OCT 10 2012
UPDATED THE FORECAST TO REFLECT THE MULTI-LAYER OF CLOUDS THAT HAVE
SPREAD INTO...AND DEVELOPED OVER...EAST KENTUCKY EARLY THIS MORNING.
ALSO EXPANDED THE SPRINKLES THROUGH 8 AM FOR FAR SOUTHEAST PARTS OF
THE CWA. OTHERWISE...TOOK THIS OPPORTUNITY TO TWEAK THE HOURLY T
AND TD GRIDS WITH RESPECT TO THE CURRENT CONDITIONS AND TRENDS.
UPDATES HAVE BEEN SENT TO THE WEB AND NDFD SERVERS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 340 AM EDT WED OCT 10 2012
...FROST ADVISORY AND A NW FREEZE WARNING TONIGHT...
06Z SFC ANALYSIS SHOWS A COLD FRONT...EXTENDING FROM A LOW CENTERED
NORTH OF MICHIGAN...ENTERING THE STATE OF KENTUCKY. THIS BOUNDARY IS
MAINLY A DRY ONE ATTM WITH JUST SOME LIGHT RAIN/SPRINKLES SHOWING UP
ON RADAR OVER CENTRAL AND NORTHERN INDIANA ALONG WITH SOME TO THE
EAST OF THE FRONT MOVING THROUGH NORTH CENTRAL TENNESSEE. A
SMATTERING OF LOW CLOUDS REMAIN OVER FAR EASTERN KENTUCKY...BUT FOR
THE MOST PART SKIES ARE CLEAR. THIS HAS ALLOWED THE VALLEYS TO DROP
OFF INTO THE UPPER 30S IN MANY CASE WHILE THE RIDGES HOLD IN THE LOWER
AND MIDDLE 40S. PATCHY FOG IS ALSO NOTED IN THE DEEPER VALLEYS OF THE
EAST. THIS WILL ALL CLEAR OUT TOWARD DAWN AS THE CLOUDS OF THE FRONT
MOVES IN ALONG WITH A STIRRING OF THE WIND FROM THE SOUTH. THE PICK
UP IN WINDS SHOULD ALSO MIX THE AIR MORE EFFECTIVELY AND ALLOW VALLEY
TEMPS TO RISE TOWARD DAWN.
THE MODELS REMAIN IN GOOD AGREEMENT ALOFT WITH THE TROUGH SWINGING
THROUGH THE GREAT LAKES AND OHIO VALLEY TODAY. THIS TROUGH AND ITS
EFFECTS WILL LIFT OUT OF THE REGION QUICKLY LATER TODAY AND SET UP A
REGIME OF SLOWLY RISING HEIGHTS...BUT ALSO FAST AND SLIGHTLY
NORTHWEST FLOW OVER THE AREA INTO THURSDAY EVENING.
THE MODEL DIFFERENCES...SLIGHT THAT THEY ARE...IN SENSIBLE WEATHER
WITH THIS SYSTEM REVOLVE PRIMARILY AROUND THE RESOLUTION AND INTERNAL
MECHANICS OF THE MODELS THEMSELVES. ACCORDINGLY...THE HIGHER
RESOLUTION HRRR AND DOWNSCALE NAMDNG SHOW ENOUGH OOMPH WITH THIS
FRONT TO PRINT OUT SMALL POPS LATER THIS MORNING AND INTO EARLY
AFTERNOON. MEANWHILE ALL THE OTHER MODELS...ASIDE FROM THE ECMWF...
ARE DRY...INCLUDING THE RUC13. PLAN ON FOLLOWING THE IDEAS OF THE
HRRR WITH SOME ECMWF SUPPORT FOR POPS TODAY. AS THERE ARE SOME SIGNS
OF PCPN SHOWING UP ON RADAR ALONG THIS BOUNDARY ATTM...SOME EXTRA
LIFT AVAILABLE COMING THROUGH THE HIGHER TERRAIN HERE...AND DECENT
DYNAMICS TO THE NORTH WILL CONTINUE A SMALL CHANCE/ISOLATED POPS
SCENARIO FOR EAST KENTUCKY TODAY...BUT CERTAINLY THE MAJORITY OF THE
AREA WILL STAY DRY. THE CLOUDS AND ANY LIGHT PCPN FROM THIS BOUNDARY
WILL MOVE OUT BY EVENING AND ALLOW FOR A CHILLY NIGHT...ESPECIALLY
ONCE THE WINDS GO LIGHT AND CALM AFTER SUNSET.
THE CLEARING SKIES AND LIGHT WINDS WILL SET THE STAGE FOR THE
COLDEST NIGHT...ACROSS ALL OF EAST KENTUCKY...OF THE YOUNG FALL
SEASON WITH WIDESPREAD AND POTENTIALLY RATHER THICK FROST A GOOD BET.
THE FROST ON TUESDAY MORNING ONLY REALLY AFFECTED LOCALIZED AREAS TO
OUR NORTHWEST WHILE FOG MANAGED TO PROTECT THE COLDER SPOTS IN THE
WESTERN PORTION OF THE CUMBERLAND VALLEY. THEREFORE FOR THE MAJORITY
OF EAST KENTUCKY FROST WILL BE THE LARGER THREAT TONIGHT AS
TEMPERATURES ARE ONLY EXPECTED TO DIP DOWN JUST BELOW FREEZING IN
ABOUT HALF THE AREA AND FOR A JUST BRIEF PERIOD TOWARDS DAWN. AS A
RESULT...WILL ISSUE A FREEZE WARNING IN THE NORTHWEST THAT SAW MORE
FROST YESTERDAY MORNING AND KICK OFF A FROST ADVISORY OVER THE REST
OF THE CWA. WILL START THESE AT MIDNIGHT AS THE DEEPER VALLEYS SHOULD
DROP OFF FAST FOLLOWING SUNSET AND A SETTLING OF THE WINDS.
HOWEVER...FREEZING TEMPERATURES WILL NOT OCCUR UNTIL CLOSER TOWARD
DAWN OVER THE NORTHWEST...BUT WIDESPREAD FROST CAN BE EXPECTED MUCH
EARLIER IN THE NIGHT. TO EASE ANY CONFUSION WITH THE TWO
FROST/FREEZE HEADLINES FOR OUR AREA...BUT VERY SIMILAR EFFECTS
EXPECTED...WILL ISSUE THEM FOR THE SAME VALID TIMES FROM MIDNIGHT
THROUGH 9 AM EDT. THURSDAY WILL BE A NICE DAY AFTER A CHILLY START
WITH PLENTY OF SUNSHINE AND ONLY A SMALL INCREASE IN CLOUDS FROM THE
WEST LATE IN THE DAY.
HAVE FOLLOWED A MIX OF THE INHERITED GRIDS...MAV GUIDANCE...AND
TERRAIN BASED EDITING FOR THE TEMPERATURES TONIGHT AND OTHERWISE. AS
FOR POPS...AGAIN RAN HIGHER THAN THE GUIDANCE FOR TODAY/S SLIGHT
CHANCES.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 355 AM EDT WED OCT 10 2012
THE FIRST ISSUE TO CONTEND WITH IN THE EXTENDED CENTERS AROUND A
SHORT WAVE CURRENTLY DROPPING SOUTH OUT OF THE FRONT RANGE OF THE
CANADIAN ROCKIES...WITH AN ASSOCIATED SFC LOW TAKING SHAPE ALONG THE
U.S./CANADIAN BORDER. MODELS REMAIN IN RELATIVELY GOOD AGREEMENT
WITH THIS DUO...BRINGING THEIR ASSOCIATED ENERGY INTO THE GREAT
LAKES LATE THURSDAY INTO FRIDAY MORNING.
HIGH PRESSURE BUILDING OVER THE COMMONWEALTH TODAY WILL BE SHIFTING
TO THE EAST BY TOMORROW NIGHT...INVOKING SOUTHERLY RETURN FLOW BACK
INTO THE AREA AHEAD OF A COLD FRONT ASSOCIATED WITH THE SFC LOW AS
IT TREKS THROUGH THE GREAT LAKES. MOISTURE PROFILES ARE LOOKING A
LITTLE BETTER THIS MORNING...AND HAVE BOOSTED POPS A BIT ACROSS THE
BOARD FOR THURSDAY NIGHT AND FRIDAY MORNING. INSTABILITY STILL DOES
NOT LOOK ALL THAT IMPRESSIVE...BUT WILL CONTINUE TO ADVERTISE
THUNDER THROUGH THIS WINDOW. HOWEVER...ATTM...IT WOULD APPEAR THAT
ANY TSTMS WOULD BE ISOLATED AND WELL BELOW SEVERE THRESHOLDS.
HIGH PRESSURE LOOKS TO TRAVERSE THE GREAT LAKES FRIDAY NIGHT THROUGH
SATURDAY IN CONJUNCTION WITH SHORT WAVE RIDGING OVERHEAD YIELDING
QUIETER WEATHER TO START THE WEEKEND. DURING THIS TIME...A CUTOFF
LOW STILL PARKED OFF THE COAST OF CA IS EXPECTED TO DIG INTO THE
DESERT SW BEFORE EVOLVING INTO MORE OF AN OPEN WAVE AS IT LIFTS
ACROSS THE PLAINS. MODELS REMAIN IN GOOD AGREEMENT WITH BRINGING
THIS FEATURE INTO THE GREAT LAKES SATURDAY NIGHT INTO SUNDAY WITH
THE ACCOMPANYING SFC REFLECTION USHERING AN ASSOCIATED COLD FRONT
INTO THE OHIO VALLEY.
ABOUT THIS TIME...MODELS BEGIN TO DIVERGE WITH THE EVOLUTION OF THE
UPPER LEVEL PATTERN. A VERY LOOSE CONSENSUS THIS MORNING SUGGESTS
SOME STALLING OF THE COLD FRONT AS IT MOVES INTO ERN KY WITH THE
PARENT UPPER LEVEL TROF PAUSING OVER THE LENGTH OF THE MS VALLEY
WHILE A SECONDARY SHORT WAVE DROPS DOWN THE BACKSIDE...DEEPENING THE
UPPER TROF BEFORE ULTIMATELY KICKING THE FRONT AND THE BULK OF ANY
LINGERING PRECIP TO THE EAST OF THE AREA BY LATE IN THE DAY MONDAY.
THEREAFTER...A SOLID CONSENSUS BECOMES NEARLY IMPOSSIBLE TO COME BY.
WITH MUCH UNCERTAINTY THIS FAR OUT...HAVE OPTED TO KEEP POPS LIMITED
TO 20 PERCENT OR LESS THROUGH THE MIDDLE OF NEXT WEEK UNTIL BETTER
MODEL AGREEMENT CAN BE ACHIEVED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 225 AM EDT WED OCT 10 2012
ALMOST ALL OF THE MVFR STRATOCU HAS DISSIPATED OVER OUR EAST...WITH
JUST SOME LINGERING PATCHES ALONG THE SPINE OF THE APPALACHIANS.
EXPECT THESE TO CONTINUE TO ERODE OVER THE NEXT COUPLE OF HOURS.
ACCORDINGLY...THE VAST MAJORITY OF EASTERN KENTUCKY WILL SEE VFR
CONDITIONS THROUGH THE REMAINDER OF THE NIGHT WITH ANY FOG FOUND ONLY
IN THE DEEPER VALLEYS. TOWARD DAWN...MID AND LOW LEVEL CLOUDS WILL
PUSH BACK ACROSS THE FORECAST AREA FROM THE WEST AS A MAINLY DRY COLD
FRONT APPROACHES. THESE CLOUDS AND THE ODD CHANCE OF A SHOWER OR
SPRINKLE WILL BE THE MAIN EFFECTS OF THE FRONT AND WILL EXIT WEST TO
EAST DURING THE AFTERNOON AND EVENING. ALSO...THERE WILL BE A SOLID
WIND SHIFT WITH THE FRONT. LIGHT SOUTHERLY WINDS WILL BECOME
SOUTHWESTERLY AND PICK UP A NOTCH JUST AHEAD OF THE FRONT DURING THE
DAY...TODAY...WITH WINDS BECOMING MORE WESTERLY AND STAYING UP BEHIND
THE BOUNDARY. LIGHT WINDS AT THE SFC EARLY THIS MORNING WILL CREATE A
MINOR SHEAR CONCERN AS THEY ARE RUNNING IN THE 20 TO 25 KT RANGE FROM
THE SOUTHWEST AT ABOUT 2K FEET OFF THE SFC.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM EDT THURSDAY FOR
KYZ044-050>052-058>060-104.
FROST ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EDT THURSDAY FOR
KYZ068-069-079-080-083>088-106>120.
&&
$$
UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM....MB
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS JACKSON KY
355 AM EDT WED OCT 10 2012
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 340 AM EDT WED OCT 10 2012
...FROST ADVISORY AND A NW FREEZE WARNING TONIGHT...
06Z SFC ANALYSIS SHOWS A COLD FRONT...EXTENDING FROM A LOW CENTERED
NORTH OF MICHIGAN...ENTERING THE STATE OF KENTUCKY. THIS BOUNDARY IS
MAINLY A DRY ONE ATTM WITH JUST SOME LIGHT RAIN/SPRINKLES SHOWING UP
ON RADAR OVER CENTRAL AND NORTHERN INDIANA ALONG WITH SOME TO THE
EAST OF THE FRONT MOVING THROUGH NORTH CENTRAL TENNESSEE. A
SMATTERING OF LOW CLOUDS REMAIN OVER FAR EASTERN KENTUCKY...BUT FOR
THE MOST PART SKIES ARE CLEAR. THIS HAS ALLOWED THE VALLEYS TO DROP
OFF INTO THE UPPER 30S IN MANY CASE WHILE THE RIDGES HOLD IN THE LOWER
AND MIDDLE 40S. PATCHY FOG IS ALSO NOTED IN THE DEEPER VALLEYS OF THE
EAST. THIS WILL ALL CLEAR OUT TOWARD DAWN AS THE CLOUDS OF THE FRONT
MOVES IN ALONG WITH A STIRRING OF THE WIND FROM THE SOUTH. THE PICK
UP IN WINDS SHOULD ALSO MIX THE AIR MORE EFFECTIVELY AND ALLOW VALLEY
TEMPS TO RISE TOWARD DAWN.
THE MODELS REMAIN IN GOOD AGREEMENT ALOFT WITH THE TROUGH SWINGING
THROUGH THE GREAT LAKES AND OHIO VALLEY TODAY. THIS TROUGH AND ITS
EFFECTS WILL LIFT OUT OF THE REGION QUICKLY LATER TODAY AND SET UP A
REGIME OF SLOWLY RISING HEIGHTS...BUT ALSO FAST AND SLIGHTLY
NORTHWEST FLOW OVER THE AREA INTO THURSDAY EVENING.
THE MODEL DIFFERENCES...SLIGHT THAT THEY ARE...IN SENSIBLE WEATHER
WITH THIS SYSTEM REVOLVE PRIMARILY AROUND THE RESOLUTION AND INTERNAL
MECHANICS OF THE MODELS THEMSELVES. ACCORDINGLY...THE HIGHER
RESOLUTION HRRR AND DOWNSCALE NAMDNG SHOW ENOUGH OOMPH WITH THIS
FRONT TO PRINT OUT SMALL POPS LATER THIS MORNING AND INTO EARLY
AFTERNOON. MEANWHILE ALL THE OTHER MODELS...ASIDE FROM THE ECMWF...
ARE DRY...INCLUDING THE RUC13. PLAN ON FOLLOWING THE IDEAS OF THE
HRRR WITH SOME ECMWF SUPPORT FOR POPS TODAY. AS THERE ARE SOME SIGNS
OF PCPN SHOWING UP ON RADAR ALONG THIS BOUNDARY ATTM...SOME EXTRA
LIFT AVAILABLE COMING THROUGH THE HIGHER TERRAIN HERE...AND DECENT
DYNAMICS TO THE NORTH WILL CONTINUE A SMALL CHANCE/ISOLATED POPS
SCENARIO FOR EAST KENTUCKY TODAY...BUT CERTAINLY THE MAJORITY OF THE
AREA WILL STAY DRY. THE CLOUDS AND ANY LIGHT PCPN FROM THIS BOUNDARY
WILL MOVE OUT BY EVENING AND ALLOW FOR A CHILLY NIGHT...ESPECIALLY
ONCE THE WINDS GO LIGHT AND CALM AFTER SUNSET.
THE CLEARING SKIES AND LIGHT WINDS WILL SET THE STAGE FOR THE
COLDEST NIGHT...ACROSS ALL OF EAST KENTUCKY...OF THE YOUNG FALL
SEASON WITH WIDESPREAD AND POTENTIALLY RATHER THICK FROST A GOOD BET.
THE FROST ON TUESDAY MORNING ONLY REALLY AFFECTED LOCALIZED AREAS TO
OUR NORTHWEST WHILE FOG MANAGED TO PROTECT THE COLDER SPOTS IN THE
WESTERN PORTION OF THE CUMBERLAND VALLEY. THEREFORE FOR THE MAJORITY
OF EAST KENTUCKY FROST WILL BE THE LARGER THREAT TONIGHT AS
TEMPERATURES ARE ONLY EXPECTED TO DIP DOWN JUST BELOW FREEZING IN
ABOUT HALF THE AREA AND FOR A JUST BRIEF PERIOD TOWARDS DAWN. AS A
RESULT...WILL ISSUE A FREEZE WARNING IN THE NORTHWEST THAT SAW MORE
FROST YESTERDAY MORNING AND KICK OFF A FROST ADVISORY OVER THE REST
OF THE CWA. WILL START THESE AT MIDNIGHT AS THE DEEPER VALLEYS SHOULD
DROP OFF FAST FOLLOWING SUNSET AND A SETTLING OF THE WINDS.
HOWEVER...FREEZING TEMPERATURES WILL NOT OCCUR UNTIL CLOSER TOWARD
DAWN OVER THE NORTHWEST...BUT WIDESPREAD FROST CAN BE EXPECTED MUCH
EARLIER IN THE NIGHT. TO EASE ANY CONFUSION WITH THE TWO
FROST/FREEZE HEADLINES FOR OUR AREA...BUT VERY SIMILAR EFFECTS
EXPECTED...WILL ISSUE THEM FOR THE SAME VALID TIMES FROM MIDNIGHT
THROUGH 9 AM EDT. THURSDAY WILL BE A NICE DAY AFTER A CHILLY START
WITH PLENTY OF SUNSHINE AND ONLY A SMALL INCREASE IN CLOUDS FROM THE
WEST LATE IN THE DAY.
HAVE FOLLOWED A MIX OF THE INHERITED GRIDS...MAV GUIDANCE...AND
TERRAIN BASED EDITING FOR THE TEMPERATURES TONIGHT AND OTHERWISE. AS
FOR POPS...AGAIN RAN HIGHER THAN THE GUIDANCE FOR TODAY/S SLIGHT
CHANCES.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 355 AM EDT WED OCT 10 2012
THE FIRST ISSUE TO CONTEND WITH IN THE EXTENDED CENTERS AROUND A
SHORT WAVE CURRENTLY DROPPING SOUTH OUT OF THE FRONT RANGE OF THE
CANADIAN ROCKIES...WITH AN ASSOCIATED SFC LOW TAKING SHAPE ALONG THE
U.S./CANADIAN BORDER. MODELS REMAIN IN RELATIVELY GOOD AGREEMENT
WITH THIS DUO...BRINGING THEIR ASSOCIATED ENERGY INTO THE GREAT
LAKES LATE THURSDAY INTO FRIDAY MORNING.
HIGH PRESSURE BUILDING OVER THE COMMONWEALTH TODAY WILL BE SHIFTING
TO THE EAST BY TOMORROW NIGHT...INVOKING SOUTHERLY RETURN FLOW BACK
INTO THE AREA AHEAD OF A COLD FRONT ASSOCIATED WITH THE SFC LOW AS
IT TREKS THROUGH THE GREAT LAKES. MOISTURE PROFILES ARE LOOKING A
LITTLE BETTER THIS MORNING...AND HAVE BOOSTED POPS A BIT ACROSS THE
BOARD FOR THURSDAY NIGHT AND FRIDAY MORNING. INSTABILITY STILL DOES
NOT LOOK ALL THAT IMPRESSIVE...BUT WILL CONTINUE TO ADVERTISE
THUNDER THROUGH THIS WINDOW. HOWEVER...ATTM...IT WOULD APPEAR THAT
ANY TSTMS WOULD BE ISOLATED AND WELL BELOW SEVERE THRESHOLDS.
HIGH PRESSURE LOOKS TO TRAVERSE THE GREAT LAKES FRIDAY NIGHT THROUGH
SATURDAY IN CONJUNCTION WITH SHORT WAVE RIDGING OVERHEAD YIELDING
QUIETER WEATHER TO START THE WEEKEND. DURING THIS TIME...A CUTOFF
LOW STILL PARKED OFF THE COAST OF CA IS EXPECTED TO DIG INTO THE
DESERT SW BEFORE EVOLVING INTO MORE OF AN OPEN WAVE AS IT LIFTS
ACROSS THE PLAINS. MODELS REMAIN IN GOOD AGREEMENT WITH BRINGING
THIS FEATURE INTO THE GREAT LAKES SATURDAY NIGHT INTO SUNDAY WITH
THE ACCOMPANYING SFC REFLECTION USHERING AN ASSOCIATED COLD FRONT
INTO THE OHIO VALLEY.
ABOUT THIS TIME...MODELS BEGIN TO DIVERGE WITH THE EVOLUTION OF THE
UPPER LEVEL PATTERN. A VERY LOOSE CONSENSUS THIS MORNING SUGGESTS
SOME STALLING OF THE COLD FRONT AS IT MOVES INTO ERN KY WITH THE
PARENT UPPER LEVEL TROF PAUSING OVER THE LENGTH OF THE MS VALLEY
WHILE A SECONDARY SHORT WAVE DROPS DOWN THE BACKSIDE...DEEPENING THE
UPPER TROF BEFORE ULTIMATELY KICKING THE FRONT AND THE BULK OF ANY
LINGERING PRECIP TO THE EAST OF THE AREA BY LATE IN THE DAY MONDAY.
THEREAFTER...A SOLID CONSENSUS BECOMES NEARLY IMPOSSIBLE TO COME BY.
WITH MUCH UNCERTAINTY THIS FAR OUT...HAVE OPTED TO KEEP POPS LIMITED
TO 20 PERCENT OR LESS THROUGH THE MIDDLE OF NEXT WEEK UNTIL BETTER
MODEL AGREEMENT CAN BE ACHIEVED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 225 AM EDT WED OCT 10 2012
ALMOST ALL OF THE MVFR STRATOCU HAS DISSIPATED OVER OUR EAST...WITH
JUST SOME LINGERING PATCHES ALONG THE SPINE OF THE APPALACHIANS.
EXPECT THESE TO CONTINUE TO ERODE OVER THE NEXT COUPLE OF HOURS.
ACCORDINGLY...THE VAST MAJORITY OF EASTERN KENTUCKY WILL SEE VFR
CONDITIONS THROUGH THE REMAINDER OF THE NIGHT WITH ANY FOG FOUND ONLY
IN THE DEEPER VALLEYS. TOWARD DAWN...MID AND LOW LEVEL CLOUDS WILL
PUSH BACK ACROSS THE FORECAST AREA FROM THE WEST AS A MAINLY DRY COLD
FRONT APPROACHES. THESE CLOUDS AND THE ODD CHANCE OF A SHOWER OR
SPRINKLE WILL BE THE MAIN EFFECTS OF THE FRONT AND WILL EXIT WEST TO
EAST DURING THE AFTERNOON AND EVENING. ALSO...THERE WILL BE A SOLID
WIND SHIFT WITH THE FRONT. LIGHT SOUTHERLY WINDS WILL BECOME
SOUTHWESTERLY AND PICK UP A NOTCH JUST AHEAD OF THE FRONT DURING THE
DAY...TODAY...WITH WINDS BECOMING MORE WESTERLY AND STAYING UP BEHIND
THE BOUNDARY. LIGHT WINDS AT THE SFC EARLY THIS MORNING WILL CREATE A
MINOR SHEAR CONCERN AS THEY ARE RUNNING IN THE 20 TO 25 KT RANGE FROM
THE SOUTHWEST AT ABOUT 2K FEET OFF THE SFC.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM EDT THURSDAY FOR
KYZ044-050>052-058>060-104.
FROST ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EDT THURSDAY FOR
KYZ068-069-079-080-083>088-106>120.
&&
$$
SHORT TERM...GREIF
LONG TERM....MB
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
340 AM EDT WED OCT 10 2012
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 340 AM EDT WED OCT 10 2012
...FROST ADVISORY AND A NW FREEZE WARNING TONIGHT...
06Z SFC ANALYSIS SHOWS A COLD FRONT...EXTENDING FROM A LOW CENTERED
NORTH OF MICHIGAN...ENTERING THE STATE OF KENTUCKY. THIS BOUNDARY IS
MAINLY A DRY ONE ATTM WITH JUST SOME LIGHT RAIN/SPRINKLES SHOWING UP
ON RADAR OVER CENTRAL AND NORTHERN INDIANA ALONG WITH SOME TO THE
EAST OF THE FRONT MOVING THROUGH NORTH CENTRAL TENNESSEE. A
SMATTERING OF LOW CLOUDS REMAIN OVER FAR EASTERN KENTUCKY...BUT FOR
THE MOST PART SKIES ARE CLEAR. THIS HAS ALLOWED THE VALLEYS TO DROP
OFF INTO THE UPPER 30S IN MANY CASE WHILE THE RIDGE HOLD IN THE LOWER
AND MIDDLE 40S. PATCHY FOG IS ALSO NOTED IN THE DEEPER VALLEYS OF THE
EAST. THIS WILL ALL CLEAR OUT TOWARD DAWN AS THE CLOUDS OF THE FRONT
MOVES IN ALONG WITH A STIRRING OF THE WIND FROM THE SOUTH. THE PICK
UP IN WINDS SHOULD ALSO MIX THE AIR MORE EFFECTIVELY AND ALLOW VALLEY
TEMPS TO RISE TOWARD DAWN.
THE MODELS REMAIN IN GOOD AGREEMENT ALOFT WITH THE TROUGH SWINGING
THROUGH THE GREAT LAKES AND OHIO VALLEY TODAY. THIS TROUGH AND ITS
EFFECTS WILL LIFT OUT OF THE REGION QUICKLY LATER TODAY AND SET UP A
REGIME OF SLOWLY RISING HEIGHTS...BUT ALSO FAST AND SLIGHTLY
NORTHWEST FLOW OVER THE AREA INTO THURSDAY EVENING.
THE MODEL DIFFERENCES...SLIGHT THAT THEY ARE...IN SENSIBLE WEATHER
WITH THIS SYSTEM REVOLVE PRIMARILY AROUND THE RESOLUTION AND INTERNAL
MECHANICS OF THE MODELS THEMSELVES. ACCORDINGLY...THE HIGHER
RESOLUTION HRRR AND DOWNSCALE NAMDNG SHOW ENOUGH OOMPH WITH THIS
FRONT TO PRINT OUT SMALL POPS LATER THIS MORNING AND INTO EARLY
AFTERNOON. MEANWHILE ALL THE OTHER MODELS...ASIDE FROM THE ECMWF...
ARE DRY...INCLUDING THE RUC13. PLAN ON FOLLOWING THE IDEAS OF THE
HRRR WITH SOME ECMWF SUPPORT FOR POPS TODAY. AS THERE ARE SOME SIGNS
OF PCPN SHOWING UP ON RADAR ALONG THIS BOUNDARY ATTM...SOME EXTRA
LIFT AVAILABLE COMING THROUGH THE HIGHER TERRAIN HERE...AND DECENT
DYNAMICS TO THE NORTH WILL CONTINUE A SMALL CHANCE/ISOLATED POPS
SCENARIO FOR EAST KENTUCKY TODAY...BUT CERTAINLY THE MAJORITY OF THE
AREA WILL STAY DRY. THE CLOUDS AND ANY LIGHT PCPN FROM THIS BOUNDARY
WILL MOVE OUT BY EVENING AND ALLOW FOR A CHILLY NIGHT...ESPECIALLY
ONCE THE WINDS GO LIGHT AND CALM AFTER SUNSET.
THE CLEARING SKIES AND LIGHT WINDS WILL SET THE STAGE FOR THE
COLDEST NIGHT...ACROSS ALL OF EAST KENTUCKY...OF THE YOUNG FALL
SEASON WITH WIDESPREAD AND POTENTIALLY RATHER THICK FROST A GOOD BET.
THE FROST ON TUESDAY MORNING ONLY REALLY AFFECTED LOCALIZED AREAS TO
OUR NORTHWEST WHILE FOG MANAGED TO PROTECT THE COLDER SPOTS IN THE
WESTERN PORTION OF THE CUMBERLAND VALLEY. THEREFORE FOR THE MAJORITY
OF EAST KENTUCKY FROST WILL BE THE LARGER THREAT TONIGHT AS
TEMPERATURES ARE ONLY EXPECTED TO DIP DOWN JUST BELOW FREEZING IN
ABOUT HALF THE AREA AND FOR A JUST BRIEF PERIOD TOWARDS DAWN. AS A
RESULT...WILL ISSUE A FREEZE WARNING IN THE NORTHWEST THAT SAW MORE
FROST YESTERDAY MORNING AND KICK OFF A FROST ADVISORY OVER THE REST
OF THE CWA. WILL START THESE AT MIDNIGHT AS THE DEEPER VALLEYS SHOULD
DROP OFF FAST FOLLOWING SUNSET AND A SETTLING OF THE WINDS. HOWEVER...
FREEZING TEMPERATURES WILL NOT OCCUR UNTIL CLOSER TOWARD DAWN OVER
THE NORTHWEST...BUT WIDESPREAD FROST CAN BE EXPECTED MUCH EARLIER IN
THE NIGHT. TO EASE ANY CONFUSION WITH THE TWO FROST/FREEZE HEADLINES
FOR OUR AREA...BUT VERY SIMILAR EFFECTS EXPECTED...WILL ISSUE THEM
FOR THE SAME VALID TIMES FROM MIDNIGHT THROUGH 9 AM EDT. THURSDAY
WILL BE A NICE DAY AFTER A CHILLY START WITH PLENTY OF SUNSHINE AND
ONLY A SMALL INCREASE IN CLOUDS FROM THE WEST LATE IN THE DAY.
HAVE FOLLOWED A MIX OF THE INHERITED GRIDS...MAV GUIDANCE...AND
TERRAIN BASED EDITING FOR THE TEMPERATURES TONIGHT AND OTHERWISE. AS
FOR POPS...AGAIN RAIN HIGHER THAN THE GUIDANCE FOR TODAY/S SLIGHT
CHANCES.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 304 PM EDT TUE OCT 9 2012
THE GFS AND ECMWF ARE IN REASONABLE AGREEMENT THROUGH SUNDAY.
SURFACE HIGH PRESSURE WILL DRIFT FROM THE CENTRAL APPALACHIANS TO
THE EAST COAST ON THURSDAY...PROVIDING THE LOCAL AREA WITH MOSTLY
SUNNY SKIES AND CONTINUED WARMING TEMPERATURES. A COLD FRONT WILL
DROP SOUTH INTO THE OHIO VALLEY ON THURSDAY NIGHT AND THEN SOUTH OF
KENTUCKY ON FRIDAY. MODELS SHOW WARM AIR ADVECTION BRINGING A QUICK
SURGE OF MOISTURE IN THE 850-700MB LAYER ALONG THE FRONT...BUT LARGE
SCALE SUPPORT ALOFT FOR PRECIP LOOKS MEAGER. THE NAM DOES SHOWS MORE
SIGNIFICANT CONVECTION WITH THE MOISTURE SURGE...BUT IS NOT
CONSISTENT IN ITS PLACEMENT. ITS GENERAL CONSENSUS IN THE LAST
COUPLE RUNS WOULD BE FOR HIGHER POPS IN OUR SOUTHERN COUNTIES. WILL
USE 20-30 PERCENT POPS THURSDAY NIGHT AND FRIDAY...WITH THE HIGHEST
POPS IN THE SOUTH.
BY FRIDAY NIGHT WHAT IS LEFT OF THE FRONT WILL BE TO OUR SOUTH AND
HIGH PRESSURE PASSING BY TO OUR NORTHEAST WILL BRING DRIER AIR AND
DECREASING CLOUDS. THE HIGH WILL BE TO OUR EAST BY SATURDAY
MORNING...WITH LOW LEVEL WARM AIR ADVECTION ALREADY UNDERWAY. A DEEP
AREA OF LOW PRESSURE TRAVELING FROM THE CENTRAL PLAINS TO THE GREAT
LAKES ON SATURDAY AND SATURDAY NIGHT WILL RESULT IN A TIGHTENING
PRESSURE GRADIENT AND A POTENTIAL FOR BREEZY MILD WINDS. MOISTURE
OFF THE GULF IS LIKELY TO REMAIN TO OUR NORTHWEST ALONG AN ADVANCING
COLD FRONT DURING THIS TIME.
THIS COLD FRONT IS SLATED TO ARRIVE ON SUNDAY...BUT WILL BE LOSING
ITS DEFINITION AND ITS PUNCH OF COOLER AND DRIER AIR BY THE TIME IT
ARRIVES. THIS WOULD LEAVE US WITHOUT ANY SIGNIFICANT CHANGE IN AIR
MASS. EVEN SO...THE AIR MASS ALREADY IN PLACE MAY BE WARM AND MOIST
ENOUGH TO SUPPORT SHOWERS OR THUNDERSTORMS...ESPECIALLY IF WE GET A
BIT OF SUPPORT FROM AN UPPER JET AS MODELS SHOW BEING POSSIBLE. WILL
CARRY LOW CHANCE POPS SUNDAY INTO SUNDAY NIGHT.
AT THIS POINT...MODEL SOLUTIONS BEGIN TO DIVERGE. THE 12Z GFS HAS
ANOTHER COLD FRONT PIVOTING AROUND THE LARGE STORM SYSTEM AS IT
HEADS THROUGH QUEBEC SUNDAY NIGHT AND MONDAY. THE FRONT APPROACHES
THE LOCAL AREA SUNDAY NIGHT AND PASSES ON MONDAY. MEANWHILE...THE
LATEST AVAILABLE ECMWF FROM 00Z SHOWS NO SECONDARY FRONT AND HAS
WARM AIR ADVECTION PERSISTING...AND AN UPPER LEVEL IMPULSE PASSING
OVER ON MONDAY NIGHT. THE GFS ENSEMBLE IS MUCH LESS DISTINCTIVE WITH
THE SECOND FRONT THAN THE OPERATIONAL GFS...BUT DOES LOOK LIKE THE
OPERATIONAL RUN WITH A SURFACE RIDGE PASSING OVER ON TUESDAY...AS
OPPOSED TO THE WARM AIR ADVECTION OF THE ECMWF. NEEDLESS TO
SAY...CONFIDENCE TAKES A HIT WITH THE CONFLICTING SOLUTIONS. WILL
USE LOW CHANCE POPS AGAIN ON MONDAY...ALTHOUGH FOR VARYING REASONS
DEPENDING ON THE MODEL SOLUTION. WILL USE ONLY SLIGHT CHANCE POPS
FOR MONDAY NIGHT AND TUESDAY AND A COMPROMISE ON TEMPS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 225 AM EDT WED OCT 10 2012
ALMOST ALL OF THE MVFR STRATOCU HAS DISSIPATED OVER OUR EAST...WITH
JUST SOME LINGERING PATCHES ALONG THE SPINE OF THE APPALACHIANS.
EXPECT THESE TO CONTINUE TO ERODE OVER THE NEXT COUPLE OF HOURS.
ACCORDINGLY...THE VAST MAJORITY OF EASTERN KENTUCKY WILL SEE VFR
CONDITIONS THROUGH THE REMAINDER OF THE NIGHT WITH ANY FOG FOUND ONLY
IN THE DEEPER VALLEYS. TOWARD DAWN...MID AND LOW LEVEL CLOUDS WILL
PUSH BACK ACROSS THE FORECAST AREA FROM THE WEST AS A MAINLY DRY COLD
FRONT APPROACHES. THESE CLOUDS AND THE ODD CHANCE OF A SHOWER OR
SPRINKLE WILL BE THE MAIN EFFECTS OF THE FRONT AND WILL EXIT WEST TO
EAST DURING THE AFTERNOON AND EVENING. ALSO...THERE WILL BE A SOLID
WIND SHIFT WITH THE FRONT. LIGHT SOUTHERLY WINDS WILL BECOME
SOUTHWESTERLY AND PICK UP A NOTCH JUST AHEAD OF THE FRONT DURING THE
DAY...TODAY...WITH WINDS BECOMING MORE WESTERLY AND STAYING UP BEHIND
THE BOUNDARY. LIGHT WINDS AT THE SFC EARLY THIS MORNING WILL CREATE A
MINOR SHEAR CONCERN AS THEY ARE RUNNING IN THE 20 TO 25 KT RANGE FROM
THE SOUTHWEST AT ABOUT 2K FEET OFF THE SFC.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM EDT THURSDAY FOR
KYZ044-050>052-058>060-104.
FROST ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EDT THURSDAY FOR
KYZ068-069-079-080-083>088-106>120.
&&
$$
SHORT TERM...GREIF
LONG TERM....HAL
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
455 PM EDT WED OCT 10 2012
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 450 PM EDT WED OCT 10 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS CONTINUE TO SHOW A TROF OVER
CNTRL NAMERICA. NEXT SHORTWAVE DROPPING INTO THE TROF IS CURRENTLY
HEADING SE THRU SASKATCHEWAN TOWARD SRN MANITOBA. THIS WAVE WILL BE
THE MAIN FCST ISSUE IN THE SHORT TERM. OTHERWISE...ALTHOUGH 850MB
THERMAL TROF (TEMPS OF -6 TO -8C) IS STILL CROSSING THE AREA...LAKE
EFFECT PCPN HAS BEEN GRADUALLY WINDING DOWN FROM W TO E DUE TO
SOMEWHAT DRIER AIR ADVECTING INTO THE AREA AND FLOW BECOMING MORE
ANTICYCLONIC. MORE IMPORTANT NEGATIVE FACTOR IS PROBABLY DAYTIME
HEATING DISRUPTING LAKE EFFECT PROCESSES.
LINGERING LAKE EFFECT PCPN WILL CONTINUE TO DIMINISH AND SHIFT MORE
OFFSHORE AS WINDS BACK WITH SFC HIGH PRES RIDGE PASSING. LAST OF THE
PCPN SHOULD EXIT NRN LUCE COUNTY AROUND 06Z. ATTENTION THEN TURNS TO
APPROACHING SHORTWAVE. THERE ISN`T MUCH DIFFERENCE IN MODELS...BUT
WILL FAVOR THE REGIONAL GEM WHICH HAS BEEN VERY CONSISTENT SHOWING
MORE PCPN WITH THIS SYSTEM. FAIRLY ROBUST DEEP LAYER FORCING PER
QVECTORS ALONG WITH DECENT ISENTROPIC ASCENT (285-290K SFCS)
SUGGESTS PCPN IS A GOOD BET...ESPECIALLY ACROSS THE N AND E...CLOSER
TO SHORTWAVE TRACK. PCPN SHOULD SPREAD INTO THE W LATE EVENING AND
REACH THE E OVERNIGHT. 1000-850MB THICKNESSES IN THE 1302-1310M
RANGE SUGGEST A MIX OF RAIN/SNOW WILL OCCUR. HIGH TERRAIN SHOULD BE
PREDOMINANTLY SNOW...TRANSITIONING TO MAINLY RAIN NEAR THE GREAT
LAKES. WITH 0.1 TO 0.3 INCHES OF PCPN...MAY SEE A SLUSHY INCH OR TWO
OF SNOW ACCUMULATION IN THE HIGH TERRAIN. WINDS MAY BACK JUST ENOUGH
FOR SOME LAKE ENHANCEMENT OFF LAKE MICHIGAN INTO THE FAR ERN FCST
AREA...SO PCPN AMOUNTS MAY BE HIGHER THERE. WITH LOW-LEVELS SLIGHTLY
WARMER...LAKE ENHANCED PCPN OVER THE E SHOULD BE MOSTLY IN THE FORM
OF RAIN. TEMPS WILL HAVE A BRIEF OPPORTUNITY TO FALL THIS EVENING
(SHOULD FALL BLO FREEZING IN MANY AREAS)...BUT THICKENING CLOUDS
WILL RESULT IN TEMPS RISING A LITTLE AFTER EARLY LOWS.
THERE MAY BE A BRIEF PERIOD OF NW FLOW LAKE ENHANCEMENT THU MORNING
BEFORE FORCING EXITS AND STRONG DEEP LAYER QVECTOR DIVERGENCE AND
MID LEVEL DRYING ARRIVE. THAT WILL HELP MORE WIDESPREAD PCPN LINGER
A BIT LONGER IN THE AREAS AFFECTED BY NW FLOW OFF LAKE SUPERIOR. CAA
DROPS 850MB TEMPS TO -5 TO -7C DURING THE DAY...WHICH WILL SUPPORT
SOME LAKE EFFECT PCPN. GIVEN EARLY SEASON/DIURNAL HEATING...IT WILL
BE MORE OF A HYBRID TYPE PCPN PATTERN WITH NOT SO MUCH BANDING OFF
THE LAKE...BUT ISOLD/SCT SHOWERS EXTENDING WELL INLAND.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 450 PM EDT WED OCT 10 2012
THURSDAY NIGHT...THE SHORTWAVE TROUGH WILL EXIT THE NRN GREAT LAKES
WITH STRONG STRONG 700-300 MB QVECTOR CONV IN ITS WAKE. AS SFC HIGH
PRES BUILDS FROM THE NRN PLAINS INTO THE UPPER MS VALLEY NW FLOW WILL
CONTINUE ACROSS LAKE SUPERIOR WITH 850 MB TEMPS INTO THE -7C TO -8C
RANGE. WITH WATER TEMPS FROM 7C TO 12C...THERE WILL BE MORE THAN
ENOUGH INSTABILITY TO SUSTAIN LAKE EFFECT PCPN. EVEN THROUGH OVERALL
WINDS WILL BE NORTHWEST...EXPECT THEAT LAKE INDUCED TROUGHING WILL
HELP TO FOCUS LOW LEVEL CONV INTO AREAS NEAR P53 AND GRAND MARAIS.
ALTHOUGH THE LONG FETCH ACROSS THE LAKE WILL KEEP TEMPS RELATIVELY
WARM OVER THE EAST...EXPECT MAINLY SNOW WITH A COATING TO HALF AN
INCH OF ACCUMULATION IN SOME LOCATIONS. OVER THE WEST...THE PCPN WILL
TAPER OFF SOONER AS THE RIDGE AND BUILDS TOWARD THE AREA WITH LIGHT
ACYC FLOW.
FRI...ANY LINGERING LAKE EFFECT PCPN INTO THE NORTHEAST CWA WILL
TAPER OFF QUICKLY IN THE MORNING AS WINDS BACK WITH THE RIDGE
BUILDING INTO THE AREA. SUNSHINE AND DEVELOPING WAA WITH SW FLOW
SHOULD HELP PUSH TEMPS INTO THE MID AND UPPER 40S...PER FCST
SOUNDINGS.
FRI NIGHT AND SAT...MODELS WERE IN GOOD AGREEMENT WITH THE OVERALL
PATTERN RESULTING IN STRONG WAA AND MOISTURE ADVECTION INTO THE
UPPER GREAT LAKES AS A STRONG SHRTWV MOVES THROUGH THE CNTRL PLAINS.
300K-310K ISENTROPIC LIFT SUPPORTED BY UPPER LEVEL DIV WITH THE
RIGHT EXIT REGION OF THE 250-300 JET OVER NRN ONTARIO WILL SUPPORT
WIDESPREAD RAIN FROM WI SPREADING INTO UPPER MI. THE NAM/SREF WAS
PREFERRED IN WITH A LATER ONSET OF PCPN AND KEEPING THE GREATER QPF
A BIT FARTHER SOUTH...CLOSER TO THE 850 MB WARM FRONT AND GREATER
ELEVATED CAPE.
SAT NIGHT INTO SUN...THE GFS...12Z GEFS AND GEM REMAINED A BIT
FARTHER NORTH WITH THE TRACK OF THE MID LEVEL SHORTWAVE AND SFC LOW
COMPARED TO THE ECMWF. SO...THERE IS GREATER UNCERTAINTY WITH THE
POSITION AND POTENTIAL FOR HEAVY PCPN ASSOCIATED WITH THE STRONG
FGEN/DEF AS THE 700 MB LOW MOVES THROUGH. WITH EITHER SCENARIO...A
COLD WIND DRIVEN RAIN MAY LINGER INTO SUNDAY WITH WRAP-AROUND PCPN
AND SOME LAKE ENHANCEMENT OFF OF LAKE SUPERIOR AS 850 MB TEMPS DROP
TO AROUND 0C.
MON-WED...MODELS WERE SIMILAR WITH A PROGRESSIVE PATTERN EARLY NEXT
WEEK BUT SHOW EXPECTED DIFFERENCES WITH DETAILS. A WAA PATTERN WITH
THE POTENTIAL FOR MORE RAIN...ESPECIALLY FROM TUE NIGHT INTO
WED...PER MDLS CONSENSUS. TEMPS ARE EXPECTED CLIMB BACK VALUES AOA
SEASONAL AVERAGES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 132 PM EDT WED OCT 10 2012
VFR CONDITIONS SHOULD BE THE RULE AT KIWD/KCMX/KSAW THRU THE AFTN
HRS AS INFLUX OF SOMEWHAT DRIER AIR HELPS TO KEEP CLOUD BASES ABOVE
3KFT. AT KSAW...SCT -SHRASN MAY STILL OCCUR BRIEFLY AT TIMES FOR THE
NEXT HR OR TWO. GUSTY WNW WILL CONTINUE THIS AFTN...ESPECIALLY AT THE
MORE EXPOSED KCMX SITE. DISTURBANCE WILL QUICKLY MOVE INTO THE AREA
TONIGHT. EXPECT A PERIOD OF MVFR CONDITIONS AS -SN/-RA SPREAD ACROSS
THE AREA. PCPN SHOULD BE MAINLY SN AT KCMX/KSAW. PCPN WILL
DIMINISH/END LATE TONIGHT/THU MORNING...BUT MVFR CIGS MAY LINGER
THRU THE MORNING AT KCMX/KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 450 PM EDT WED OCT 10 2012
ATTENTION OVER THE NEXT 24HRS IS ON LOW PRES WHICH WILL BE MOVING
ACROSS OR JUST N OF LAKE SUPERIOR LATE TONIGHT AND THU MORNING.
STRONGEST WINDS THRU EARLY THIS EVENING WILL BE OVER ERN LAKE
SUPERIOR WHERE NW WINDS WILL BE GUSTING TO 30KT WITH A FEW GUSTS TO
GALE FORCE. WINDS WILL BRIEFLY BE IN THE 15-25KT RANGE FOR A TIME
TONIGHT BEFORE INCREASING AGAIN LATE AS THE LOW ARRIVES IN THE UPPER
LAKES. SW WINDS MAY GUST TO NEAR 30KT LATE TONIGHT. OF MORE CONCERN
WILL BE THE NW WINDS DEVELOPING THU AS THE LOW SHIFTS E OF THE LAKE.
AIDED BY INCREASINGLY COLDER AIR AND PRES RISES APPROACHING FROM THE
NW...A PERIOD OF NW GALES IS A POSSIBILITY OVER THE E HALF OF LAKE
SUPERIOR. MAY NEED TO HOIST A GALE WARNING IF NEW GUIDANCE ARRIVING
THIS EVENING MORE SOLIDLY SUPPORTS GALES.
A MODERATELY STRONG LOW PRESSURE SYSTEM IS EXPECTED TO TRACK THROUGH
THE WESTERN GREAT LAKES. SOUTH WINDS OF 15 TO 25 KNOTS ARE EXPECTED
AHEAD OF THE SYSTEM SATURDAY WHILE NORTHERLY 15 TO 25 KNOT WINDS ARE
WILL DEVELOP AS THE LOW PULLS AWAY SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLB
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS DULUTH MN
1226 AM CDT WED OCT 10 2012
.AVIATION...06Z TAFS.
VFR EXPECTED THROUGH MUCH OF THE FORECAST. SFC LOW STILL PROGGED TO
MOVE ALONG THE INTERNATIONAL BORDER PUSHING A COLD FRONT THROUGH THE
TERMINALS. BEST OPPORTUNITY FOR LIGHT RAIN WILL AFFECT HIB AND INL
WITH MVFR VSBYS AT INL BETWEEN 18Z AND 22Z. DLH/BRD/HYR MAY BE FAR
ENOUGH S OF THE LOW CENTER WHERE THE LIGHT RAIN WILL BE MORE SPARSE
AND HAVE A VCSH MENTION. THE DRY SLOT MOVES THROUGH AFTER 00Z
BRINGING AND END TO THE LIGHT RAIN.
&&
.PREV DISCUSSION... /ISSUED 940 PM CDT TUE OCT 9 2012/
UPDATE...
COVERAGE OF RAIN/SNOW/SLEET SHOWERS HAVE DIMINISHED THIS
EVENING...WITH A FEW REPORTS OF SNOW SHOWERS OR LIGHT RAIN OVER THE
PAST HOUR OR TWO. LOSS OF HEATING HAS HELPED DIMINISH THE
SHOWERS...AND WE SHOULD CONTINUE TO SEE A DIMINISHING TREND
OVERNIGHT. THE EXCEPTION MAY BE ALONG A PORTION OF THE SOUTH
SHORE. COLD AIR...850MB TEMPS OF -7 TO -8C AND NORTHWEST WINDS MAY
COMBINE TO PRODUCE SOME LAKE EFFECT SHOWERS ALONG THE SOUTH SHORE.
THE FETCH DOES APPEAR TO BE TOO WEST OF NORTH IN THE 1000-850MB
LAYER FOR SIGNIFICANT PRECIP. WE WILL KEEP SOME HIGHER POPS OVER
THE SNOWBELT OF IRON COUNTY...TO PORTIONS OF ASHLAND COUNTY TONIGHT.
PREV DISCUSSION... /ISSUED 610 PM CDT TUE OCT 9 2012/
AVIATION...00Z TAFS
COLD AIR OVER THE NORTHLAND AND CYCLONIC FLOW ALOFT HAVE COMBINED
TO PRODUCE RAIN...SNOW...AND SLEET SHOWERS THIS AFTERNOON AND
EVENING. SOME OF THE SHOWERS HAVE REDUCED VISIBILITY TO 3
MILES...AND PRODUCED GUSTY WINDS. THE SHOWERS SHOULD DIMINISH IN
MOST PLACES AS THE EVENING PROGRESSES...BUT PERSIST LONGER IN THE
SNOWBELT OF IRON AND PERHAPS INTO ASHLAND COUNTY AS WELL.
A MIXTURE OF MVFR AND VFR CEILINGS WERE OCCURRING...EVEN DIPPING
BRIEFLY TO IFR WITH THE STRONGER SHOWERS. WE EXPECT THIS TO
CONTINUE INTO THE EVENING HOURS...THEN WE COULD SEE SOME REDUCTION
IN CEILING OVERNIGHT. THE HRRR SHOWS LOWER CEILINGS DEVELOPING
AFTER 04Z OR SO. THERE WILL BE BREAKS IN THE CLOUDS IN SPOTS...AS
SUGGESTED BY VISIBLE SATELLITE IMAGERY. WE DO LOWER CEILINGS TO
MVFR FOR MOST SPOTS TONIGHT. THE CEILINGS WILL COME UP ON
WEDNESDAY.
PREV DISCUSSION... /ISSUED 337 PM CDT TUE OCT 9 2012/
SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT.
AT 330 PM...SCATTERED RAIN AND SNOW SHOWERS CONTINUED TO MOVE
THROUGH THE NORTHLAND. THERE HAVE BEEN SOME RAIN AND SNOW MIX RAIN
SHOWERS AT TIMES...BUT A CHECK WITH SOME OBSERVERS AND AREA
WEB CAMS REVEALS NO ACCUMULATION. TEMPS WERE GENERALLY NEAR 40
NORTH AND IN THE 40S SOUTH. WINDS WERE A BIT GUSTY...ESPECIALLY
NEAR LAKE SUPERIOR...WHERE SOME 25 KNOT WINDS WERE FOUND.
TONIGHT...THE RAIN AND SNOW SHOWERS SHOULD CONTINUE INTO THE
EVENING ACROSS MUCH OF THE AREA...BUT THEN DECREASE CONSIDERABLY
AS THE NIGHT WEARS ON. NOT REALLY EXPECTING ANY ACCUMULATION...BUT
THE DLH LOCAL RUN OF THE WRF WAS INDICATING SOME STREAMERS FROM
MANY LARGER INLAND LAKES...ESPECIALLY LAKE OF THE WOODS. THIS
COULD RESULT IN SOME LIGHT ACCUMULATION DOWNWIND OF SOME OF THE
INTERIOR LAKES OVERNIGHT. OVERNIGHT LOWS SHOULD DROP TO THE 20S.
WEDNESDAY...THE DAY WILL START DRY FOR MOST AREAS...WITH A MIX OF
SUN AND CLOUDS. CLOUDS WILL THEN INCREASE BY AFTERNOON AS A
VIGOROUS ALBERTA CLIPPER SLIDES INTO CENTRAL NORTH DAKOTA BY MID
AFTERNOON. THE RESULT SHOULD BE A SWATH OF WIDESPREAD SNOW...MIXED
WITH SOME RAIN...FOR AT LEAST THE NORTHERN HALF OF THE CWA. LOOKS
LIKE THE BEST CHANCE FOR SEEING SOME ACCUMULATION WOULD BE THE
WESTERN IRON RANGE THROUGH WEDNESDAY AFTERNOON.
WEDNESDAY NIGHT...ACCUMULATING SNOW SHOULD SPREAD ACROSS THE
INTERNATIONAL BORDER AND IRON RANGE AREAS THROUGHOUT THE EVENING.
A COUPLE INCHES OF SNOW IS NOT OUT OF THE QUESTION...BUT THE BIG
QUESTION WILL BE HOW MUCH OF THE PRECIPITATION FALLS IN THE FORM
OF RAIN. THINK THE STRONG WAA WILL RESULT IN ENOUGH DYNAMIC
COOLING TO OVERCOME LOW LEVEL WARM AIR...RESULTING IN ACCUMULATING
SNOWFALL. THE BEST CHANCE FOR A LIGHT RAIN/SNOW MIX WOULD COME
SOUTH OF THE STRONGEST FORCING...NAMELY THE AREA JUST SOUTH OF THE
IRON RANGE.
LONG TERM...THURSDAY THROUGH MONDAY.
NORTHLANDERS WILL WAKE UP THURSDAY MORNING IN THE WAKE OF A WEAK
CLIPPER SYSTEM THAT WILL HAVE PASSED THROUGH THE REGION OVERNIGHT.
IT WILL BE ANOTHER COLD DAY WITH GUSTY NORTHWEST WINDS. THERE MAY BE
SOME LINGERING SNOW OR RAIN SHOWERS ACROSS NORTHERN MINNESOTA...AND
POSSIBLY NEAR IRONWOOD IN IRON COUNTY DUE TO LAKE EFFECT SHOWERS.
HIGH PRESSURE SHOULD THEN MOVE INTO THE FA THURSDAY NIGHT AND
FRIDAY...PROVIDING A WINDOW OF DRY WEATHER AND CLEARER SKIES.
HOWEVER...THE WEEKEND WILL TAKE A BIG CHANGE WHEN A STRONG LOW
PRESSURE SYSTEM MOVES OUT OF THE PLAINS TOWARDS THE UPPER MIDWEST.
THIS SYSTEM WILL BRING RELATIVELY WARM AND MOISTURE RICH AIR TO THE
FA...SO POPS DRAMATICALLY INCREASE OVER THE WEEKEND. IT APPEARS MUCH
OF THE FA COULD GET AT LEAST A QUARTER INCH OF RAIN. THERE MAY EVEN
BE SOME THUNDER ACROSS NORTHWESTERN WISCONSIN ON SATURDAY. PERIODS
OF SHOWERS COULD CONTINUE PAST THE WEEKEND INTO MONDAY.
&&
.POINT TEMPS/POPS...
DLH 31 43 25 46 / 40 10 0 10
INL 28 41 23 45 / 60 20 0 10
BRD 33 46 24 49 / 30 0 0 10
HYR 33 47 23 48 / 30 10 0 10
ASX 34 47 28 48 / 30 10 10 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 11 AM CDT THIS MORNING FOR LSZ121-
146>148.
&&
$$
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1215 AM CDT WED OCT 10 2012
.AVIATION...06Z TAF. WIND SHEAR AN EARLY CONCERN WITH LIGHT WESTERLY
WINDS AT THE SURFACE...BUT A HOWLING NORTHWEST WIND OF 40KTS AT THE
TOP OF THE 2K LAYER PER VAD WIND PROFILES. RUC SUGGESTS THIS WILL
LAST THROUGH 10Z AND THEN ABATE QUICKLY. BEYOND THAT...VFR CONDITIONS
ARE EXPECTED WITH NO VISIBILITY RESTRICTIONS. HIGH PRESSURE SLIDING
SOUTHEAST OF THE KGRI AREA BY MIDDAY...WITH RESULT IN TIGHTENING
SURFACE PRESSURE GRADIENT AND GUSTY SOUTHWEST WINDS THIS AFTERNOON...
POSSIBLY UP TO 20KTS AT TIMES.
&&
.PREV DISCUSSION... /ISSUED 700 PM CDT TUE OCT 9 2012/
AVIATION...00Z KGRI TAF. MOSTLY CLEAR BUT SOME WIND FOR AFTERNOON
WEDNESDAY WITH INCREASED LOW-LEVEL LAPSE RATES.
PREV DISCUSSION... /ISSUED 331 PM CDT TUE OCT 9 2012/
SHORT TERM...THROUGH WEDNESDAY AFTERNOON...GUSTY NORTHERLY WINDS
WILL CONTINUE THROUGH THE LATE AFTERNOON HOURS BEHIND THIS MORNINGS
COLD FRONT...WHICH AS OF 20Z...IS DRAPED FROM SOUTHWESTERN KANSAS
NORTHEASTWARD ACROSS IOWA AND INTO WISCONSIN. AS THE SURFACE HIGH
BUILDING IN BEHIND THIS FRONT TRANSITIONS SOUTHWARD ACROSS NEBRASKA
OVERNIGHT...EXPECT CLEARING SKIES AND LIGHT WINDS TO MAKE FOR AN
UNSEASONABLY COOL NIGHT ACROSS THE LOCAL AREA...WITH MORNING LOWS
WEDNESDAY EXPECTED TO RANGE FROM THE LOWER TO MID 20S ACROSS OUR
NORTH...TO NEAR FREEZING ACROSS PORTIONS OF NORTH CENTRAL KANSAS.
OTHER THAN THESE COOLER TEMPERATURES...NO OTHER SIGNIFICANT WEATHER
CONCERNS THROUGH THE MORNING HOURS WEDNESDAY ARE ANTICIPATED AT THIS
TIME.
THEREAFTER...EXPECT THE SURFACE HIGH ACROSS THE CENTRAL PLAINS TO
CONTINUE TO RAPIDLY SINK SOUTHWARD DURING THE DAY ON
WEDNESDAY...WITH RETURN FLOW AROUND THE HIGH AND INCREASING 850 MB
TEMPS TO RESULT IN A FAIRLY PLEASANT FALL DAY ACROSS THE REGION.
WHILE AFTERNOON HIGH TEMPERATURES WILL CLIMB TO VERY NEAR SEASONAL
NORMS...FOCUS WILL SHIFT TO ELEVATED FIRE WEATHER CONDITIONS AS
DEWPOINTS WILL REMAIN DEPRESSED AND SOUTHERLY WINDS COULD BECOME A
BIT GUSTY DURING THE AFTERNOON HOURS. AT THIS TIME...BOTH WINDS AND
RHS APPEAR TO BE JUST SHY OF CRITICAL LEVELS...BUT WILL NEED TO
CONTINUE TO MONITOR...ESPECIALLY WESTERN AREAS AND ACROSS
KANSAS...WHERE AFTERNOON WIND SPEEDS ON THE BACKSIDE OF THE HIGH
WILL BE THE STRONGEST. AS A RESULT...WILL CONTINUE TO MENTION
ELEVATED FIRE WEATHER DANGER FOR WEDNESDAY IN HWO.
LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
.ONE MORE MINOR/BARELY NOTICEABLE REINFORCEMENT TO THE COOL TEMPS
THU THEN CONCERN TURNS TO TSTM POTENTIAL FRI NIGHT AS WE TRANSITION
TO A WARMER PATTERN...
PATTERN: SOME HIGH LATITUDE LONGWAVE RETROGRESSION WILL RESULT IN A
PATTERN SHIFT OVER THE NEXT 10 DAYS...WHICH WILL FAVOR TEMPS AT OR
ABOVE NORMAL. THIS BEGINS AS EARLY AS SAT. THE LAST CANADIAN AIR TO
SPILL DOWN THE PLAINS WILL BE THU`S COOL FRONT. THE MULTI-DAY GFS
ENSEMBLE MEANS SUGGESTS A COMPLETE REVERSAL OF N AMERICA HGT
ANOMALIES OVER THE NEXT 10 DAYS...WHICH WILL TRANSLATE TO LESS NW
FLOW HERE AND MORE SW FLOW. 6-10/8-14 DAY OUTLOOKS ARE NOW BACK TO
HIGHER PROBABILITIES FOR ABOVE NORMAL TEMPS.
QPF: THE ONLY OPPORTUNITY FOR SOME MEANINGFUL RAINFALL WILL OCCUR
FRI NIGHT /POSSIBLY LINGERING INTO SAT MORNING E OF HWY 281?/. GEFS
SPAGHETTI PLOTS FOR 0.5" QPF IN 24 HRS SUGGESTS SOME "SPOTTY" HALF
INCH AMTS ARE POSSIBLE...WITH THE HIGHEST PROBABILITIES OVER OUR KS
COUNTIES. THE BEST PROBS FOR MORE WIDESPREAD 0.5" WILL BE JUST E OF
OUR FCST AREA.
UPPER-LEVELS: WNW FLOW WILL CONTINUE THRU THU. SHORTWAVE RIDGE
ARRIVES FRI IN ADVANCE OF UPPER LOW /CURRENT OFF OF CA/ HEADING E
THRU THE 4-CORNERS. THIS LOW WILL MOVE THRU SAT...INITIATING LEE
CYCLOGENESIS FRI NIGHT. THEREAFTER THE FLOW REMAINS ZONAL WHICH
FAVORS SEASONABLE TEMPS.
AFTER SATURDAY`S SFC LOW DEPARTS...NO REAL COOL-DOWN AS SERN USA
HIGH PRES MAINTAINS S FLOW IN COMBINATION WITH A LEE TROF TO THE W.
THE DAILY DETAILS:
WED NIGHT: INCREASING CLOUDS IN THE WARM SECTOR. LOW TEMPS ARE BIAS
CORRECTED GFS 2M TEMPS /32-46F/. THE LOW-MID 30S NEAR ORD ARE
DEPENDENT ON THE TIMING OF THE FRONT AND ARE THEREFORE BELOW
AVERAGE. COULD SEE LOW TEMPS ONLY DROP TO AROUND 40F IF FRONT
DOESN`T MOVE THRU UNTIL DAYBREAK.
IN COORDINATION WITH NEIGHBORING OFFICES...SKY COVER HAS BEEN
INCREASED FROM PREVIOUS FCSTS FOR WED NIGHT-FRI TIME FRAMES...BUT
NOT AS MUCH AS WOULD HAVE PREFERRED.
THU: MORNING COLD FRONTAL PASSAGE. TEMPS ARE BELOW AVERAGE
CONFIDENCE. TOUGH TO GET A READ ON WHAT THEY WILL DO AND EXTENSIVE
CLOUD COVER COMPLICATES. LOW-LEVEL THERMAL RIDGE WILL STILL REMAIN
OVER THE FCST AREA IN THE MRNG. SO DESPITE CAA BELIEVE WE COULD SEE
QUICK WARM-UP "IF" THERE ARE SUBSTANTIVE BREAKS IN THE CLOUDS. AS OF
NOW WE HAVE 60-75F IN THE FCST.
THU NIGHT: P/CLOUDY ON AVERAGE BUT MAY BE M/CLOUDY AT TIMES. LOW
TEMPS ARE BIAS CORRECTED BLEND OF ALL GUIDANCE WARMED A COUPLE DEG
/29-46F/. THIS COULD STILL BE 3-5F TOO COLD IF LOW CLOUDS DEVELOP/
THICKEN AS HINTED IN CROSS SECTIONS/SOUNDINGS.
FRI: BUST POTENTIAL IS LARGE FOR TEMPS. THU`S COOL FRONT STALLS NEAR
KS-OK BORDER AND BEGINS ACTING AS A WARM FRONT WITH THE APPROACH OF
THE UPPER LOW. OVERALL...EXPECT CLOUDY SKIES. 09Z/SREF PROBS FOR
01" QPF INCREASE ABOVE 60% OVER OUR KS COUNTIES 15-18Z AND OVER OUR
NEB COUNTIES AFTER 18Z. SO MAINTAINED CHANCE POPS FOR SHWRS AND
POSSIBLE THUNDER...ESPECIALLY AFTER 18Z. THE NAEFS SHOWS SOME SPREAD
E OF THE MEAN AT 00Z/SAT SUGGESTIVE OF SOME MEMBERS FAVORING A BIT
FASTER SCENARIO. THESE POPS WILL COVER POTENTIALLY FASTER START TO
THE RAIN.
TEMPS ARE CONSENSUS OF ALL 2M GUIDANCE WHICH OFFERS 52-65F. DEPENDENT
ON CLOUDS/PCPN THOSE TEMPS IN THE 60S S/E OF GRI COULD END UP BEING
JAMMED IN THE 50S.
FRI NIGHT: SFC LOW EJECTS OUT OF CO...PROBABLY JUST N OF THE FCST
AREA. RICH MSTR WILL BRIEFLY NOSE IN WITH 1" PW ENCOMPASSING THE
ENTIRE FCST AREA...AND MAX VALUE AROUND 1.50". THE 06Z GFS ENSEMBLE
MEAN OF 1.42" IS 3 STANDARD DEVIATION ABOVE NORMAL!
BOTH EC/GFS SHOWALTER -3 WITH MUCAPE APPROACHING 1000 J/KG. LOTS OF
TIME FOR THESE NUMBERS TO CHANGE. MOST OF THE INSTABILITY IS ALOFT
BUT THERE COULD BE A BRIEF WINDOW FOR SFC-BASED INSTABILITY NEAR
TIME OF COOL FRONTAL PASSAGE. EFFECTIVE SHEAR /1-6 KM/ IS CURRENTLY
FCST BELOW 20 KTS. SFC BASED SHEAR 35-40 KTS.
SAT: POSSIBLY SOME LEFTOVER SHWRS/TSTMS E OF HWY 281 IN THE MRNG?
OTHERWISE...CLEARING AND WINDY IN THE DRY SLOT! WE COULD FLIRT WITH
ADVISORY LEVEL WIND GUSTS /45 MPH/. TEMPS ARE 66-76F.
THE 12Z/EC HAS COME IN 230 MILES SW OF ITS 00Z CYCLE AT H5. THIS IS
ON THE SLOW SIDE OF THE GUIDANCE ENVELOPE/CLUSTERING SO IT`S BEEN
DISCOUNTED FOR NOW.
SUN: VERY NICE FOR OUTDOOR ACTIVITIES! SUNNY WITH SEASONABLE TEMPS
/71-77F/ AND LIGHT WINDS.
SUN NGT: UNCERTAINTY BUT PROBABLY DRY. WE`VE SEEN THE 00Z/EC AND
12Z/GEM WHICH HAVE A SHORTWAVE TROF AND SOME MEASURABLE QPF. THE 12Z
EC/GFS SAY NO.
MON-WED: P/CLOUDY. COULD BE WARMER THAN WE`VE CURRENT FCST WITH SOME
80S POSSIBLE AS LOW PRES EJECTS THRU THE NRN PLAINS.
THE HGT GRADIENT WILL TIGHTEN OVER THE E PAC BEGINNING SUN AS HGTS
FALL OVER THE GULF OF AK AND SUBTROPICAL HIGH PRES STRENGTHENS OFF
CA. THE PAST 2 CYCLES OF THE EC/GFS HAVE A 160-180 KT UPPER JET
WHICH WILL EVENTUALLY SHOULD INITIATE LEE CYCLOGENESIS SOMETIME
TOWARD THE MIDDLE OF NEXT WEEK...AS THE JET SPILLS OVER THE ROCKIES.
THE GEFS MEAN IS SUPPORTIVE WITH ITS 150 KTS ON DAY 7!
BY TUE 10/16...THE NAEFS HAS 100M OF SPREAD OVER THE NRN ROCKIES AT
500 MB. SO WHILE WE KNOW SOMETHING WILL BECOMING OUR WAY...ITS
INTENSITY AND TIMING REMAIN UNCERTAIN. EITHER WAY LOW AMPLITUDE FLOW
WILL LIKELY CAP THE REGION WITH WARM TEMPS ALOFT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAY ME
911 AM EDT WED OCT 10 2012
.SYNOPSIS...
LOW PRESSURE WILL EXIT OFFSHORE TODAY WELL EAST OF THE REGION. A
COLD FRONT WILL CROSS THE AREA TONIGHT WITH COOL HIGH PRESSURE
BEHIND IT. ANOTHER FRONT WILL CROSS THE REGION ON FRIDAY WITH EVEN
COLDER AIR BEHIND IT. HIGH PRESSURE WILL SETTLE OVER THE MID
ATLANTIC REGION EARLY IN THE WEEKEND. LOW PRESSURE WILL TRACK
FROM THE UPPER GREAT LAKES ON SUNDAY TO THE SAINT LAWRENCE VALLEY
ON MONDAY, PULLING ITS ASSOCIATED WARM AND COLD FRONTS ACROSS THE
AREA. HIGH PRESSURE FOLLOWS FOR TUESDAY.
&&
.NEAR TERM /TODAY/...
9AM UPDATE... RAIN CONTINUES TO SPREAD NORTHWARD OUT OF SOUTHERN
NEW ENGLAND THIS MORNING. THIS IS IN ASSOCIATION WITH ANOTHER
SHORTWAVE TROUGH IN THE SOUTHERLY FLOW AHEAD OF THE TROUGH MOVING
OUT OF THE GREAT LAKES. WEAK SURFACE LOW PRESSURE IS ALSO
CONTRIBUTING TO THE SHOWERS. THIS WILL TRACK NORTHWARD TODAY AND
LIKELY MAKE FOR A RAINY DAY FOR A GOOD PART OF THE AREA. ONLY
CHANGES WERE TO POP FORECAST TO BETTER REFLECT TIMING OF
PRECIPITATION ARRIVAL AND BETTER RAIN CHANCES.
UPDATE...LOW CLOUDS CONTINUE TO ROLL NORTHWARD AS A SOUTHERLY
FLOW DEVELOPS JUST ABOVE THE SURFACE AND AN APPROACHING TROUGH
MOVES EAST. SHOWERS HAVE DEVELOP OVER LONG ISLAND NEW YORK AND
PORTIONS OF SOUTHERN NEW ENGLAND. BASED ON THESE TRENDS...HAVE
INCREASED POPS FOR TODAY...ESPECIALLY OVER FAR SOUTHWEST
MAINE...AS WELL AS SOUTHERN AND WESTERN NEW HAMPSHIRE. THIS TREND
IS SIMILAR TO THE GFS SOLUTION...WHICH HAS MUCH HIGHER POPS FOR
TODAY THAN THE NAM. LATEST HRRR RUN INDICATES THAT MOST OF THE
SHOWER ACTIVITY WILL REACH SOUTHERN NEW HAMPSHIRE AROUND 13Z-
14Z...WHICH APPEARS TO BE TOO SLOW.
HAVE ADJUSTED TEMPS...DEW POINTS AND CLOUD COVER BASED ON LATEST
OBSERVATIONS THIS MORNING.
HAVE UPDATED MARINE SECTION BELOW. STRONG COLD ADVECTION AND
INCREASING GRADIENT MAY ALLOW FOR A COUPLE GUSTS INTO GALE FORCE
BY EARLY THURSDAY MORNING.
PREVIOUS DISCUSSION...
CEILINGS AROUND 6 KFT WILL BE STUBBORN TO EXIT THE REGION
CONSIDERING THE PASSAGE OF A SLOW MOVING AREA OF LOW PRESSURE WELL
OFF THE COAST. IN ADDITION...WARM AIR ADVECTION WILL CONSOLIDATE
MOISTURE IN OUR REGION...TRIGGERING A FEW SCATTERED SHOWERS DURING
THE DAY.
BLENDED THE MUCH WARMER MET NUMBERS WITH THE COOLER MAVS FOR
DAYTIME HIGHS.
&&
.SHORT TERM /TONIGHT AND THURSDAY/...
THERE WILL BE SCATTERED SHOWERS THIS EVENING WITH THE
APPROACH...THEN PASSAGE OF A STRONG COLD FRONT. HIGHEST POPS ONCE
AGAIN WILL BE OVER NORTHERN SECTIONS. IT IS THESE AREAS THAT WILL
ALSO HAVE THE MOST CLOUD COVER...AND THE LINGERING THREAT OF A
SHOWER...DUE TO THE UPSLOPING CONDITIONS. A COUPLE OF THESE
SHOWERS MAY TURN TO SNOW SHOWERS OVER THE HIGHER TERRAIN LATER IN
THE NIGHT.
BY THURSDAY...SOME MID AND HIGH LEVEL CLOUDS WILL ALREADY BE
APPROACHING FROM THE WEST AS A FAST MOVING SYSTEM RACES TOWARDS
NEW ENGLAND. HOWEVER...EXPECT THE GUSTY WINDS TO GRADUALLY SUBSIDE
DURING THE DAY.
MODELS ARE QUITE CONSISTENT IN THE TIMING OF THIS SYSTEM FOR LATE
IN THE WEEK.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
WE BEGIN THE PERIOD WITH AN IMPULSE RIDING EAST-SOUTHEAST ALONG
THE INTERNATIONAL BORDER INTO NEW ENGLAND...WITH A SURFACE
REFLECTION A WEAK LOW AND COLD FRONTAL PASSAGE EARLY ON FRIDAY.
SURFACE HIGH PRESSURE WITH DRY AIR AND BELOW NORMAL TEMPERATURES
FOLLOWS THIS SYSTEM FOR FRIDAY NIGHT THROUGH EARLY SUNDAY. A
SHORT WAVE ARRIVES FROM THE UPPER MIDWEST ON SUNDAY. AN ASSOCIATED
SURFACE LOW TRACKS FROM THE UPPER GREAT LAKES ON SUNDAY TO THE
SAINT LAWRENCE VALLEY ON MONDAY PULLING ITS ASSOCIATED WARM AND
COLD FRONTS ACROSS THE AREA. HIGH PRESSURE FOLLOWS FOR TUESDAY.
&&
.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM...CIGS AND VSBYS WILL IMPROVE TODAY. HOWEVER...A STRONG
COLD FRONT WILL ALLOW FOR SCATTERED SHOWERS LATER TONIGHT AND AN
ABRUPT WIND SHIFT TO THE WEST BY THURSDAY. ANOTHER STRONG COLD
FRONT WILL FOLLOW EARLY FRIDAY MORNING.
LONG TERM...
FRI...AREAS OF MVFR IN SHOWERS.
SUN...AREAS OF MVFR IN SHOWERS.
&&
.MARINE...
SHORT TERM...SEAS STILL RUNNING HIGH ALONG THE OUTER WATERS THIS
MORNING...HENCE THE SCA CONTINUES. SCAS WILL BE REQUIRED ONCE
AGAIN FOR LATER TONIGHT AND THURSDAY AS WINDS AND SEAS INCREASE
ALONG AND WITH THE PASSAGE OF THE STRONG COLD FRONT. THERE MAY
BE A FEW GUSTS INTO GALE...WITH STRONG COLD ADVECTION AND STRONG
GRADIENT.
LONG TERM...
FRI...A SMALL CRAFT FOR WINDS AND SEAS IS POSSIBLE.
SUN...A SMALL CRAFT FOR WINDS AND SEAS IS POSSIBLE.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EDT THURSDAY FOR ANZ150-152-
154.
&&
$$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
954 PM EDT THU OCT 11 2012
.SYNOPSIS...
A COLD FRONT WILL DROP SOUTHEAST TONIGHT...AND BRING A CHANCE FOR
RAIN SHOWERS...MAINLY OVER CENTRAL NEW YORK. HIGH PRESSURE WILL
BUILD INTO THE REGION BEHIND THIS FRONT ON FRIDAY...AND BRING
CLEAR SKIES AND COLD AIR FRIDAY NIGHT ENDING THE GROWING SEASON.
DRY AND MILDER CONDITIONS ARE EXPECTED ON SATURDAY. THE NEXT
CHANCE FOR SHOWERS WILL COME SATURDAY NIGHT AND SUNDAY AS A WARM
FRONT MOVES THROUGH THE REGION.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
10 PM UPDATE...
FNT AND ASSOCIATED PCPN SEEMS TO BE HOLDING UP A BIT JUST NORTH OF
THE FCST AREA...AWAITING THE WV MVG THRU THE CNTRL LAKES. XPCT THE
FNT AND PCPN TO BEGIN TO MVE SEWRD ONCE AGAIN LTR TNGT AS THE WV
APRCHS. HRRR SEEMS TO HAVE A GOOD HANDLE ON THE ADVANCE OF THE
PCPN SHIELD. FCSTD TEMPS IN GOOD SHAPE...JUST SOME MINOR
ADJUSTMENTS FOR THE UNEQUAL COOLING OF THE HILLS AND VLYS IN THE
AREA. TWEEKED THE MINS DOWN JUST A BIT...CLSR IN LINE WITH THE
BLENDED MOS GUID. PRVS DISC CONTS BLO.
CDFNT WILL DROP SEWD TNGT WITH A BAND OF CLDS AND -SHRA. THE
-SHRA MAY DIMINISH AS THE FNT HEADS INTO E PA TWDS DAYBREAK...AND
WE`VE KEPT THE HIEST POPS ACRS CNTRL NY TNGT (LOW LIKELY/HI CHC
POPS). TNGT`S FCST MINS INDICATE BEST POTNL FOR ISOLD FROST WILL
ACRS THE CATSKILLS AND PORTIONS OF THE POCONOS WHERE CLDS WILL BE
LATER TO MOV IN...BUT TEMPS ARE MARGINAL AND WITH CLD DECK FCST TO
MOV IN LATER TNGT THINK POTNL IS MARGINAL (IN ADDN...MUCH COLDER
TEMPS ARE IN THE CARDS FOR FRI NGT). WE LEANED TWDS THE WARMER
SIDE OF GDNC FOR TNGT`S MINS GIVEN EXPECTATION OF SOME WIND AND
XPCTD INCRS IN CLD CVR LATER TNGT.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
RESIDUAL MSTR BEHIND THE FNT..AIDED BY LAKE ONTARIO...IS XPCTD TO
PERSIST TMRW MRNG ACRS CNTRL NY...WITH MAYBE A FEW -SHRA. WE CAN`T
TOTALLY RULE OUT A FEW FLAKES MIXING IN OVER THE HIEST TRRN TMRW
MRNG BUT IT LOOKS VERY MARGINAL AND THEREFORE WON`T ADD TO THE WX
GRIDS.
STRONG DEEP SUBSIDENCE BEHIND THE FNT VERY EVIDENT IN THE OMEGA
T-H XSXNS AFTER 18Z WHICH WILL HELP ERODE/DSPT THE CLD CVR. THERE
COULD BE A FEW STRAY CLDS ACRS OUR FAR NW/NRN ZONES...BUT ALL IN
ALL AN XCLNT RADIATIONAL COOLING SITUATION WILL SET UP. ISSUED A
FROST WATCH FOR FRI NGT AS IT APEARS THIS WILL BE THE END OF THE
GROWING SEASON.
THE HIGH MOVS OFFSHORE ALLOWING A SW FLOW TO DVLP ON SAT. WE`LL
LIKELY SEE AN INCRS IN MID/UPR CLDS SAT AFTN IN ADVANCE OF THE NXT
S/WV. NON-DIURNAL TEMP TRENDS...OR STEADY TEMPS APPEAR LIKELY SAT
NGT IN ADVANCE OF THE WMFNT MAINLY ALONG THE LAKE PLAIN DUE TO
INCRSNG SW FLOW ON SAT NGT. XPCT SHRA TO OVERSPREAD THE RGN AS THE
WMFNT APRCHS...WITH THE BEST CHCS ACRS CNTRL AND NRN ZONES WHERE
ISEN LIFT IS STRONGEST.
THE WMFNT RAINS SHUD LIFT NWD ON SUNDAY MRNG...AND WOULD NOT BE
SUPRISED TO SEE MOST OF THE CWA REMAIN DRY ON SUNDAY...BUT WE LEFT
LOW CHC POPS IN FOR SUNDAY AFTN FOR CONSISTENCY. 925 TEMPS ON SUNDAY
ACRS THE FINGER LAKES AND CNTRL SRN TIER WOULD SUPPORT MAXES WELL
INTO THE U70S WE HAD FULL SUN...BUT IT APPEARS THAT AT A MINIMUM
WE`LL HAVE A BKN-OVC MID/UPR DECK WHICH WILL TEMPER MAXES. SO
STAYED CLOSE TO MOS GDNC WITH MAXES APRCHNG 70 WRN ZONES...WITH
MAXES IN THE L60S FAR SE ZONES.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
2 PM UPDATE...LONG TERM GUIDANCE REMAINS IN GOOD AGREEMENT THAT
THE BEST SHOT AT PRECIPITATION WILL COME SUNDAY NIGHT INTO EARLY
MONDAY WITH A COLD FRONT. TEMPS WILL BE MILD SUNDAY NIGHT AHEAD OF
THE FRONT...WITH 40S TO LOWER 50S EXPECTED. DRIER AIR WILL BUILD
IN BEHIND THE FRONT MONDAY BUT WILL MAINTAIN CHANCE POPS DURING
THE DAY...ESPECIALLY UP NORTH...WITH AN H5 TROF STILL MOVING THROUGH.
WEAK RIDING BUILDS IN TUESDAY AND WEDNESDAY AND WITH A DEVELOPING
SOUTHERLY FLOW...WE WILL ONCE AGAIN TURN MILD. HIGHS BY WEDNESDAY
LOOK TO BE BACK INTO THE 60S AS 850 TEMPS CLIMB TOWARD +6C ON THE
0Z EURO. WITH THE NEW 12Z GFS NUMBERS COMING IN CLOSER TO +10...WE
MAY EVEN BE A TAD TOO COOL RIGHT NOW IN OUR GRIDS. NEXT SHOT AT
RAIN COMES THURSDAY WITH THE NEXT FRONT.
&&
.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
A HIGH DECK WILL THICKEN AND LOWER OVERNIGHT. HOWEVER VFR
CONDITIONS WILL HOLD FOR MOST OF THE NIGHT ACROSS THE SOUTHERN
TERMINALS, AND AT LEAST THROUGH 6Z TO THE NORTH.
A FRONTAL SYSTEM WILL DIP SOUTHEASTWARD OVERNIGHT, PUSHING HIGHER
RELATIVE HUMIDITIES OVER NY/PA. THIS SHOULD MANIFEST ITSELF IN A
2000-3000 FOOT DECK WITH WIDELY SCATTERED LIGHT SHOWERS. THE
MOISTURE WILL ARRIVE IN RME/SYR AROUND 6Z-7Z, IN ITH/BGM/ELM AROUND
8Z-9Z, AND AVP BETWEEN 10Z-12Z.
A PUSH OF DRIER AIR DURING THE LATE MORNING WILL BREAK UP LOW
CLOUDS, AND CAUSE WINDS TO BECOME GUSTY. WEST-NORTHWEST WINDS WILL
GUST TO 20-25 KNOTS DURING THE AFTERNOON.
OUTLOOK...
FRI NGT/SAT/SUN...VFR.
SUN NGT/MON...MVFR IN SHRA.
TUE...VFR.
&&
.CLIMATE...
NEAR RECORD LOW TEMPERATURES POSSIBLE SATURDAY MORNING OCTOBER
13TH. A COLD HIGH PRESSURE SYSTEM IS EXPECTED TO COVER THE REGION
BY SATURDAY MORNING AND COULD BRING WIDESPREAD FROST AND FREEZING
CONDITIONS TO THE REGION. RECORD LOWS THAT COULD BE CHALLENGED ARE
AS FOLLOWS: RECORD (YEAR) SAT AM FORECAST LOW
GREATER BINGHAMTON AIRPORT 28 (1993) 27
SCRANTON/WILKES BARRE AIRPORT 29 (1993) 28
SYRACUSE AIRPORT 29 (2006) 28
ITHACA AIRPORT 25 (1964) 26
ELMIRA/CORNING AIRPORT 25 (1951) 24
ROME/GRIFFIS AIRPORT 26 (1993) 26
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...FREEZE WATCH FROM FRIDAY EVENING THROUGH SATURDAY MORNING FOR
PAZ038>040-043-044-047-048-072.
NY...FREEZE WATCH FROM FRIDAY EVENING THROUGH SATURDAY MORNING FOR
NYZ009-015>018-022>025-036-037-044>046-055>057-062.
&&
$$
SYNOPSIS...
NEAR TERM...DGM
SHORT TERM...
LONG TERM...HEDEN
AVIATION...DJP
CLIMATE...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
209 PM EDT WED OCT 10 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA THIS AFTERNOON...BRINGING ANOTHER CHANCE OF SHOWERS.
BEHIND THE FRONT...LAKE EFFECT SHOWERS AND MUCH COOLER AIR WILL
AFFECT THE REGION TONIGHT AND THURSDAY MORNING FOR AREAS EAST OF
LAKE ONTARIO. OTHERWISE FOR THE REST OF THE AREA CHILLIER FALL
LIKE CONDITIONS WILL PREVAIL FOR THE REMAINDER OF THE WEEK. A
LARGE HIGH PRESSURE SYSTEM WILL SETTLE OVER THE REGION SATURDAY
MORNING WITH A CHANCE FOR WIDESPREAD FROST AND FREEZING
CONDITIONS.
&&
.NEAR TERM /THROUGH TONIGHT/...
10 AM UPDATE...
DRIZZLE AND OCNL PATCHY FOG IN THE HIGHER TERRAIN RMNS TO THE
EAST OF THE I-81 CORRIDOR THIS MRNG UNDER MARINE LAYER. 12Z MODEL
GUIDANCE INDICATES THIS MARINE LYR WL HANG IN UNTIL 17Z-18Z BFR H9
WINDS SHIFT ARND TO THE SW AHD OF THE APPCHG CDFNT. THIS SFC BNDRY
IS RAPIDLY MVG THRU OH AT THIS HR WITH AN AREA OF ISOLD SHOWERS
AND/OR VIRGA WORKING INTO WRN NY AHD OF IT. CUD SEE A SPRINKLE OR
TWO OUT OF THIS DECK AS THE LATEST HRRR IS NOT INSISTENT ON THIS
AREA OF PCPN, THUS HV TWEAKED POP/WX GRIDS TO ACCNT FOR THIS.
THIS FNT WL WORK THRU A GOOD CHUNK OF THE CWA LTR THIS
AFTN...MAINLY ACRS NY STATE BUT WITH A FEW SHOWERS REACHING DOWN
INTO NEPA. MIDNIGHT SHIFT ACCNTD FOR THIS IN THE POPS GRIDS SO NO
NEED TO CHG THE LATER HRS TDA AND WL LET THEM RIDE.
PREV DISCUSSION BLO...
KBGM 88D VWP SHOWS A LAYER OF SOUTH TO SOUTHWEST FLOW BETWEEN 2
AND 7 THOUSAND FEET ABOVE GROUND LEVEL IN ASSOCIATION WITH THE
SOUTHERLY FLOW AHEAD OF THE NEXT SIGNIFICANT UPPER LEVEL WAVE AND
SURFACE FRONT MOVING THROUGH THE GREAT LAKES REGION. THIS
SOUTHERLY FLOW WAS ADVECTING MOISTURE ABOVE A COOLER LAYER FROM
THE SFC TO 925 MB WHICH WAS SEEN WELL IN THE OBSERVATIONS AS A
LOW- LEVEL SOUTHEASTERLY SFC FLOW. SFC TEMPERATURES AND DEWPOINTS
WERE IN THE UPPER 40S AND LOWER 50S WITH DEWPOINTS A COUPLE
DEGREES LOWER. THE LATEST RAP MODEL ALSO HAD DEWPOINTS IN THE
UPPER 40S AT 925 MB. IN CONTRAST...ABOVE THIS LAYER...THERE WERE
DEWPOINTS RUNNING IN THE LOWER 50S AS PER MODEL SOUNDINGS. THIS
WAS LEADING TO SATURATION AND LO AND BEHOLD THE RADAR WAS SHOWG
PATCHY DRIZZLE MAINLY E OF A SYR-TOWANDA LINE FLOWING NORTH TO
NORTHEAST IN ASSOCIATION WITH THIS S-SW FLOW. IN ADDTN...CLOUD
CIGS SUGGESTS THAT THE MOUNTAINS IN THE POCONOS...CATSKILLS AND
HIGHLANDS OF NORTHERN PA ABOVE 1800 FEET WERE SOCKED IN WITH FOG.
MOUNT POCONO WAS 1/2SM FG...SO I SUSPECT FOG IS VERY PATCHY IN THE
HIGH TERRAIN. PUT PATCHY DENSE FOG IN ERN PART OF CWA IN GRIDS
ABOVE 1800 FEET WHICH IS NOT MUCH...EXCEPT IN CATSKILLS. SINCE THE
LOW- LEVEL FLOW HAS WEAKENED WEST OF THIS CLOUD AND DRIZZLE LAYER
(W OF SYR-TOW) SKIES HAVE CLEARED. FOG PRODUCT SATELLITE IMAGE
SUGGESTS COOLER MARINE-LIKE CLOUD LAYER WILL STAY TO THE E OF
THESE AREAS OVERNIGHT. THIS IS SUPPORTED BY MODEL GUIDC FOR THE
MOST PART. THUS I WILL KEEP CLDS AND DRIZZLY/PATCHY HIGH ELEVATION
FOG OUT FINGER LAKES AND WEST OVERNIGHT
THE LOW-LEVEL SFC TO 925 MB FLOW PATTERN WILL RESPOND TO THE
APPROACHING GREAT LAKES SYSTEM THIS AM BY TURNING THE WINDS MORE
SWRLY WHICH WILL ADVECT THE DRIZZLY/LOW MOISTURE TO THE EAST INTO
ERN NY BY 18Z. THUS I MOVE THE PATCHY DRIZZLE AND FOG EAST OF THE
CATSKILLS BY LATE MORNING.
THEN WE BEGIN TO FEEL THE EFFECT OF THE SIGNIFICANT UPPER LEVEL
GREAT LAKE TROUGH AND ASSOCIATED LOW-LEVEL FRNT. THE PV LOVE
ASSOCIATED WITH THE UPPER LEVEL WAVE REACHES INTO NY AND NRN PA BY
18Z AND ACTUALLY DIGS INTO NY AND PA BY 03Z THIS EVENING. THIS IS
A REFLECTION OF THE STRONG LL COLD AIR ADVECTION. THIS PUSHES THE
850 MB FRONT TO ABT ROC-ELZ BY 18Z. THE 850 MB FRNT WILL THEN MOVE
EAST AND REACH UCA-BGM-TOW BY 21Z AND CATSKILLS/POCONOS BY 00Z
AND CLEAR ALL OF NE PA AND SE NY BY 03Z OR SO.
MODELS SEEM TO HAVE MOST OF THE PRECIP ALONG THE 850 MB FRONT
TODAY. THE PRECIP THEN FIZZLES AS IT WORKS E OF C NY AND NE PA. THEN
THE STRG COLD AIR ADVECTION BEHIND THE 850 MB FRNT TAKES OVER AND
LEADS TO PLENTY OF SC AND A SHARP DROP IN 850 MB TEMPS TO -4C
BTWN 6Z AND 12Z THU. LAKE ONTARIO TEMPERATURES ARE RUNNING ARND
16Z...WHICH GIVES A 20C DIFFERENTIAL. THIS IS EXTREME INSTABILITY.
THE LOW-LEVELS APPEAR TOO WARM ESPECIALLY IF ENUF SENSIBLE AND
LATENT HEATING TAKES PLACE FROM THE LAKE WATERS WHICH IS ASSUMED.
IN THIS CASE...IT WUD BE TOO WARM FOR ANY EARLY LAKE SNOWS AT THIS
POINT IN NC NY. HOWEVER...WILL HAVE LAKE EFFECT RAIN SHOWERS
DOWNWIND OF LAKE ONTARIO ON A 280 DEGREE FLOW TONIGHT.
COLLABORATED WITH KBUF WFO ON LAKE RAIN SHOWERS POSITIONING
TONIGHT VIA ISC GRIDS. REST OF CWA WILL SEE SOME LAKE CLOUDS BUT
LIKELY IT WILL REMAIN MOSTLY DRY TONIGHT.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY NIGHT/...
FOR THURSDAY...LAKE EFFECT SHOWERS RAPIDLY LIFT NORTHWARD INTO NRN
NY AS THE LOW-LEVEL FLOW BACKS TO MORE W-SW IN ADVANCE OF THE NEXT
SHORT WAVE AS ASSOCIATED SFC FRNT REACHES THE ERN GREAT LAKES
THURSDAY. SINCE THE FLOW WILL BE MORE W-SW IT WILL DRY OUT SO I
SEE A LOT OF SUNSHINE DEVELOPING WITH SEASONABLY CHILLY FALL
TEMPERATURES IN THE 50S MOST AREAS.
LATER THURSDAY AND THURSDAY NIGHT...GFS...EURO...CMC AND NAM ALL
BRING DOWN A COLD FRONT FROM THE NORTH ASSOCIATED WITH THE
PASSAGE OF AN UPPER LEVEL WAVE ACROSS SOUTHEASTERN CANADA. THE
MODELS DIFFER IN TIMING A BIT WITH THE GFS THE FASTEST BRINGING THE
CLDS AND SHOWERS DOWN...THE NAM IS SLOWEST WITH THE EURO AND CMC A
COMPROMISE. WILL GO WITH THE COMPROMISE FOR NOW AS THERE IS
UNCERTAINTY. HAVE CHC TO LIKELY POPS FOR RAIN SHOWERS WITH AND
BEHIND FROPA THU NGT AND FRI AM. THEN I CAN SEE SOME LAKE EFFECT
RAIN SHOWERS AND CLOUDS LINGERING DOWNWIND FROM LAKE ONTARIO AT
LEAST THRU FRI AM. BY FRI PM AND FRI NGT...LARGE COLD HIGH
PRESSURE COVERS THE REGION. SKIES WILL CLEAR...WINDS WILL GO LIGHT
AND MANY OF OUR TREES ARE EITHER AT PEAK COLORS WITH QUITE A FEW
ALREADY DROPPED ALREADY. THEREFORE LITTLE TO NO EVAPOTRANSPIRATION.
THIS WILL KEEP DEWPOINTS DOWN SO I COULD SEE WIDESPREAD FREEZING
TEMPERATURES ENTIRE CWA SAT AM...MANY AREAS POTENTIALLY IN THE 20S.
COLDEST VALLEYS POSSIBLY EVEN FLIRTING WITH UPPER TEENS. KELM MEX
GUIDC SHOWING MIN OF 23 SAT WITH THE EURO GUIDC GOING FOR 25 AT
KELM. WE HAVE RURAL SPOTS THAT GET EVEN LOWER THAN ELM. ONLY FLY
IN THE OINTMENT IS IF THERE IS SOME PATCHY LAKE EFFECT CLOUDS
WHICH WUD HOLD TEMPS UP. IF IT HOLDS CLEAR WE LIKELY WILL HAVE A
WIDESPREAD FREEZE OR EVEN HARD FREEZE. RECORD MINIMUMS COULD BE
CHALLENGED. WILL HIGHLIGHT FREEZE POTENTIAL IN HWO FOR SATURDAY
AM.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
AGAIN FOLLOWED HPC GUIDANCE FOR THE MED RNG...WHICH DOES NOT BUY INTO
THE 00Z EURO DEPCTION OF AN AMPLIFYING S/WV OVER THE MID ATLC BY
NXT TUE/WED. 12Z CANADIAN SUPPORTS THE 12Z GFS IN THIS REGARD. SO
THE MAIN THEME IS A CONTINUATION OF THE PROGRESSIVE FLOW REGIME.
SYSTEM CRNTLY OVER CA IS FCST TO EJECT OUT AND TRACK
ENEWD...APRCHNG THE FCST AREA ON SUN. THIS WILL ALLOW LOW PRES TO
TRACK NEWD FROM THE WRN GTLAKES INTO QUEBEC ON SUN NGT WHICH WILL
BRING A CHC OF SHRA. ANOTHER S/WV DROPS SEWD RIGHT BEHIND IT
KEEPING IN A CHC FOR SHRA ON MON AND PSBLY MON NGT. BRIEF RIDGING
SHUD BRING A NICE DAY ON TUE...AND DRY WX COULD PERSIST INTO WED
BEFORE THE NXT IN THE SERIES OF WAVES APRCHS. NO CHGS TO HPC TEMPS
WHICH ARE A LTL COOLER THAN YDA`S GDNC AND THIS TREND LOOKS GOOD.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 2 PM...CDFNT IS PASSING THRU THE FCST AREA. A BAND OF SCT
-SRHA AND MVFR/IFR CIGS WILL ACCOMPANY THE FRONT THIS
AFTN...MAINLY IN THE 18-21Z TIME FRAME. OVRNGT...WRLY TO NW FLOW
WILL ALLOW BAND OF LAKE-ENHANCED SHRA TO DVLP E OF LAKE ONTARIO.
WE XPCT THIS BAND TO GET INTO THE RME AREA ARND 06Z...SLOWLY
DROPPING TIL ARND 12Z WHEN IT`S SRN PERIPHERY COULD BRUSH SYR. AT
RME...WE PLAYED MVFR CONDITIONS AFTER 06Z...AND INTRODUCED THE
POTNL AT SYR IN THE 09-12Z TIME FRAME. ELSEWHERE...PATCHY MVFR
APPEARS PSBL AT OTHER SITES UNTIL EARLY THIS EVNG DUE TO DIURNALLY
ENHANCED STRATO-CU BEHIND THE FNT...BUT THESE CLDS SHUD DIMINISH
LATER THIS EVNG. COULD SEE SOME BKN CLDS FROM LAKE ERIE AT ELM FOR
A WHILE THIS EVNG BUT XPCT THEY`LL REMAIN VFR. AT THIS POINT WE
DID NOT BUY INTO THE VLY FOG THE MOS GUIDANCE WAS SUGESTING AT
ELM...BUT LATER SHIFTS WILL HAVE TO MONITOR. BAND LIFTS NWD TMRW
MRNG...WITH VFR ALL SITES...BUT MVFR WIL LIKELY LINGER AT RME TIL
LATE MRNG.
WINDS BECMG W TO NW BEHIND THE FNT 15-20 KTS...DIMINSHING A BIT
LATER THIS EVNG...THEN WRLY 10-20 KTS ON THU.
OUTLOOK...
THU NGT...CONDITIONS DETERIORATING TO MVFR IN SHRA WITH CDFNT.
FRI...MVFR EARLY SRN NY AND NE PA NEAR THE CDFNT...WITH SCT MVFR
CNTRL NY IN THE AFTN.
FRI NGT/SAT/SUN...VFR.
SUN NGT/MON...MVFR IN SHRA.
&&
.CLIMATE...
NEAR RECORD LOW TEMPERATURES POSSIBLE SATURDAY MORNING OCTOBER
13TH. A COLD HIGH PRESSURE SYSTEM IS EXPECTED TO COVER THE REGION
BY SATURDAY MORNING AND COULD BRING WIDESPREAD FROST AND FREEZING
CONDITIONS TO THE REGION. RECORD LOWS THAT COULD BE CHALLENGED ARE
AS FOLLOWS:
RECORD (YEAR) SAT AM FORECAST LOW
GREATER BINGHAMTON AIRPORT 28 (1993) 30
SCRANTON/WILKES BARRE AIRPORT 29 (1993) 30
SYRACUSE AIRPORT 29 (2006) 31
ITHACA AIRPORT 25 (1964) 28
ELMIRA/CORNING AIRPORT 25 (1951) 26
ROME/GRIFFIS AIRPORT 26 (1993) 27
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN/PVN
SHORT TERM...DJN
CLIMATE...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1008 AM EDT WED OCT 10 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA THIS AFTERNOON...BRINGING ANOTHER CHANCE OF SHOWERS.
BEHIND THE FRONT...LAKE EFFECT SHOWERS AND MUCH COOLER AIR WILL
AFFECT THE REGION TONIGHT AND THURSDAY MORNING FOR AREAS EAST OF
LAKE ONTARIO. OTHERWISE FOR THE REST OF THE AREA CHILLIER FALL
LIKE CONDITIONS WILL PREVAIL FOR THE REMAINDER OF THE WEEK. A
LARGE HIGH PRESSURE SYSTEM WILL SETTLE OVER THE REGION SATURDAY
MORNING WITH A CHANCE FOR WIDESPREAD FROST AND FREEZING
CONDITIONS.
&&
.NEAR TERM /THROUGH TONIGHT/...
10 AM UPDATE...
DRIZZLE AND OCNL PATCHY FOG IN THE HIGHER TERRAIN RMNS TO THE
EAST OF THE I-81 CORRIDOR THIS MRNG UNDER MARINE LAYER. 12Z MODEL
GUIDANCE INDICATES THIS MARINE LYR WL HANG IN UNTIL 17Z-18Z BFR H9
WINDS SHIFT ARND TO THE SW AHD OF THE APPCHG CDFNT. THIS SFC BNDRY
IS RAPIDLY MVG THRU OH AT THIS HR WITH AN AREA OF ISOLD SHOWERS
AND/OR VIRGA WORKING INTO WRN NY AHD OF IT. CUD SEE A SPRINKLE OR
TWO OUT OF THIS DECK AS THE LATEST HRRR IS NOT INSISTENT ON THIS
AREA OF PCPN, THUS HV TWEAKED POP/WX GRIDS TO ACCNT FOR THIS.
THIS FNT WL WORK THRU A GOOD CHUNK OF THE CWA LTR THIS
AFTN...MAINLY ACRS NY STATE BUT WITH A FEW SHOWERS REACHING DOWN
INTO NEPA. MIDNIGHT SHIFT ACCNTD FOR THIS IN THE POPS GRIDS SO NO
NEED TO CHG THE LATER HRS TDA AND WL LET THEM RIDE.
PREV DISCUSSION BLO...
KBGM 88D VWP SHOWS A LAYER OF SOUTH TO SOUTHWEST FLOW BETWEEN 2
AND 7 THOUSAND FEET ABOVE GROUND LEVEL IN ASSOCIATION WITH THE
SOUTHERLY FLOW AHEAD OF THE NEXT SIGNIFICANT UPPER LEVEL WAVE AND
SURFACE FRONT MOVING THROUGH THE GREAT LAKES REGION. THIS
SOUTHERLY FLOW WAS ADVECTING MOISTURE ABOVE A COOLER LAYER FROM
THE SFC TO 925 MB WHICH WAS SEEN WELL IN THE OBSERVATIONS AS A
LOW- LEVEL SOUTHEASTERLY SFC FLOW. SFC TEMPERATURES AND DEWPOINTS
WERE IN THE UPPER 40S AND LOWER 50S WITH DEWPOINTS A COUPLE
DEGREES LOWER. THE LATEST RAP MODEL ALSO HAD DEWPOINTS IN THE
UPPER 40S AT 925 MB. IN CONTRAST...ABOVE THIS LAYER...THERE WERE
DEWPOINTS RUNNING IN THE LOWER 50S AS PER MODEL SOUNDINGS. THIS
WAS LEADING TO SATURATION AND LO AND BEHOLD THE RADAR WAS SHOWG
PATCHY DRIZZLE MAINLY E OF A SYR-TOWANDA LINE FLOWING NORTH TO
NORTHEAST IN ASSOCIATION WITH THIS S-SW FLOW. IN ADDTN...CLOUD
CIGS SUGGESTS THAT THE MOUNTAINS IN THE POCONOS...CATSKILLS AND
HIGHLANDS OF NORTHERN PA ABOVE 1800 FEET WERE SOCKED IN WITH FOG.
MOUNT POCONO WAS 1/2SM FG...SO I SUSPECT FOG IS VERY PATCHY IN THE
HIGH TERRAIN. PUT PATCHY DENSE FOG IN ERN PART OF CWA IN GRIDS
ABOVE 1800 FEET WHICH IS NOT MUCH...EXCEPT IN CATSKILLS. SINCE THE
LOW- LEVEL FLOW HAS WEAKENED WEST OF THIS CLOUD AND DRIZZLE LAYER
(W OF SYR-TOW) SKIES HAVE CLEARED. FOG PRODUCT SATELLITE IMAGE
SUGGESTS COOLER MARINE-LIKE CLOUD LAYER WILL STAY TO THE E OF
THESE AREAS OVERNIGHT. THIS IS SUPPORTED BY MODEL GUIDC FOR THE
MOST PART. THUS I WILL KEEP CLDS AND DRIZZLY/PATCHY HIGH ELEVATION
FOG OUT FINGER LAKES AND WEST OVERNIGHT
THE LOW-LEVEL SFC TO 925 MB FLOW PATTERN WILL RESPOND TO THE
APPROACHING GREAT LAKES SYSTEM THIS AM BY TURNING THE WINDS MORE
SWRLY WHICH WILL ADVECT THE DRIZZLY/LOW MOISTURE TO THE EAST INTO
ERN NY BY 18Z. THUS I MOVE THE PATCHY DRIZZLE AND FOG EAST OF THE
CATSKILLS BY LATE MORNING.
THEN WE BEGIN TO FEEL THE EFFECT OF THE SIGNIFICANT UPPER LEVEL
GREAT LAKE TROUGH AND ASSOCIATED LOW-LEVEL FRNT. THE PV LOVE
ASSOCIATED WITH THE UPPER LEVEL WAVE REACHES INTO NY AND NRN PA BY
18Z AND ACTUALLY DIGS INTO NY AND PA BY 03Z THIS EVENING. THIS IS
A REFLECTION OF THE STRONG LL COLD AIR ADVECTION. THIS PUSHES THE
850 MB FRONT TO ABT ROC-ELZ BY 18Z. THE 850 MB FRNT WILL THEN MOVE
EAST AND REACH UCA-BGM-TOW BY 21Z AND CATSKILLS/POCONOS BY 00Z
AND CLEAR ALL OF NE PA AND SE NY BY 03Z OR SO.
MODELS SEEM TO HAVE MOST OF THE PRECIP ALONG THE 850 MB FRONT
TODAY. THE PRECIP THEN FIZZLES AS IT WORKS E OF C NY AND NE PA. THEN
THE STRG COLD AIR ADVECTION BEHIND THE 850 MB FRNT TAKES OVER AND
LEADS TO PLENTY OF SC AND A SHARP DROP IN 850 MB TEMPS TO -4C
BTWN 6Z AND 12Z THU. LAKE ONTARIO TEMPERATURES ARE RUNNING ARND
16Z...WHICH GIVES A 20C DIFFERENTIAL. THIS IS EXTREME INSTABILITY.
THE LOW-LEVELS APPEAR TOO WARM ESPECIALLY IF ENUF SENSIBLE AND
LATENT HEATING TAKES PLACE FROM THE LAKE WATERS WHICH IS ASSUMED.
IN THIS CASE...IT WUD BE TOO WARM FOR ANY EARLY LAKE SNOWS AT THIS
POINT IN NC NY. HOWEVER...WILL HAVE LAKE EFFECT RAIN SHOWERS
DOWNWIND OF LAKE ONTARIO ON A 280 DEGREE FLOW TONIGHT.
COLLABORATED WITH KBUF WFO ON LAKE RAIN SHOWERS POSITIONING
TONIGHT VIA ISC GRIDS. REST OF CWA WILL SEE SOME LAKE CLOUDS BUT
LIKELY IT WILL REMAIN MOSTLY DRY TONIGHT.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
FOR THURSDAY...LAKE EFFECT SHOWERS RAPIDLY LIFT NORTHWARD INTO NRN
NY AS THE LOW-LEVEL FLOW BACKS TO MORE W-SW IN ADVANCE OF THE NEXT
SHORT WAVE AS ASSOCIATED SFC FRNT REACHES THE ERN GREAT LAKES
THURSDAY. SINCE THE FLOW WILL BE MORE W-SW IT WILL DRY OUT SO I
SEE A LOT OF SUNSHINE DEVELOPING WITH SEASONABLY CHILLY FALL
TEMPERATURES IN THE 50S MOST AREAS.
LATER THURSDAY AND THURSDAY NIGHT...GFS...EURO...CMC AND NAM ALL
BRING DOWN A COLD FRONT FROM THE NORTH ASSOCIATED WITH THE
PASSAGE OF AN UPPER LEVEL WAVE ACROSS SOUTHEASTERN CANADA. THE
MODELS DIFFER IN TIMING A BIT WITH THE GFS THE FASTEST BRINGING THE
CLDS AND SHOWERS DOWN...THE NAM IS SLOWEST WITH THE EURO AND CMC A
COMPROMISE. WILL GO WITH THE COMPROMISE FOR NOW AS THERE IS
UNCERTAINTY. HAVE CHC TO LIKELY POPS FOR RAIN SHOWERS WITH AND
BEHIND FROPA THU NGT AND FRI AM. THEN I CAN SEE SOME LAKE EFFECT
RAIN SHOWERS AND CLOUDS LINGERING DOWNWIND FROM LAKE ONTARIO AT
LEAST THRU FRI AM. BY FRI PM AND FRI NGT...LARGE COLD HIGH
PRESSURE COVERS THE REGION. SKIES WILL CLEAR...WINDS WILL GO LIGHT
AND MANY OF OUR TREES ARE EITHER AT PEAK COLORS WITH QUITE A FEW
ALREADY DROPPED ALREADY. THEREFORE LITTLE TO NO EVAPOTRANSPIRATION.
THIS WILL KEEP DEWPOINTS DOWN SO I COULD SEE WIDESPREAD FREEZING
TEMPERATURES ENTIRE CWA SAT AM...MANY AREAS POTENTIALLY IN THE 20S.
COLDEST VALLEYS POSSIBLY EVEN FLIRTING WITH UPPER TEENS. KELM MEX
GUIDC SHOWING MIN OF 23 SAT WITH THE EURO GUIDC GOING FOR 25 AT
KELM. WE HAVE RURAL SPOTS THAT GET EVEN LOWER THAN ELM. ONLY FLY
IN THE OINTMENT IS IF THERE IS SOME PATCHY LAKE EFFECT CLOUDS
WHICH WUD HOLD TEMPS UP. IF IT HOLDS CLEAR WE LIKELY WILL HAVE A
WIDESPREAD FREEZE OR EVEN HARD FREEZE. RECORD MINIMUMS COULD BE
CHALLENGED. WILL HIGHLIGHT FREEZE POTENTIAL IN HWO FOR SATURDAY
AM.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
2 AM UPDATE...
LONG TERM LOOKS GOOD. MODELS SIMILAR. HIGH PRESSURE AND DRY
SATURDAY BUT BELOW NORMAL TEMPERATURES. WARMING SUNDAY BUT SHOWERS
WITH A WARM FRONT. COLD FRONT ON MONDAY WITH SHOWERS THEN A RIDGE
OF HIGH PRESSURE FOR TUESDAY AND WEDNESDAY. SLOW WARMING AS UPPER
LEVEL HEIGHTS RISE. ONLY MINOR CHANGES TO THE GRIDS.
PREVIOUS DISCUSSION...
PROGRESSIVE PTRN OVER THE MEDIUM RNG WITH S/WV`S PASSING EVERY
COUPLE OF DAYS W/ASSCD FNTL SYSTEMS. HIGH PRESSURE XPCTD TO BE
CNTRD OVER THE FCST AREA BY LATER FRI NGT...AND CLEARING SKIES MAY
ALLOW FOR AN AREA-WIDE FROST/FREEZE AND AN OFFICIAL END TO THE
GROWING SEASON. THE HIGH WILL SLIDE EWD TO THE CST BY SUNDAY
EVNG...WITH A VERY NICE DAY ANTICIPATED ON SAT. THE NXT S/WVS
APRCH FROM THE GTLAKES/OH VLY ON SUNDAY/SUN NGT WITH MORE -SHRA.
MON AND TUE LOOK DRY AT THIS TIME ALTHO A STRAY -SHRA CAN`T BE
RULED OUT SO WE RETAINED THE SLGT CHC POPS FOR THIS TIME. HPC
GUIDANCE LOOKED GOOD AND USED WITH ONLY MINOR TWEEKS.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
630 AM UPDATE...
A SOLID MARINE LAYER IS ACROSS THE SOUTHEAST TWO THIRDS OF THE
CWA. MORE LOW VFR CLOUDS APPROACHING FROM THE SW AND HIGH CLOUDS
FROM THE WEST. SOME SPOTTY DRIZZLE AND RAIN SHOWERS ALSO BEING
REPORTED AVP AND BGM EAST. RME...BGM...AVP WILL STAY UNDER A
IFR/MVFR DECK UNTIL AROUND 16Z. AVP JUST ABOVE 1K FT AND COULD
FALL FOR AN HOUR OR TWO 12 TO 14Z. BGM ALREADY VERY LOW IFR AND AT
FLIGHT MINIMUMS...ALSO EXPECTED SOME MVFR OR MAYBE IFR VSBY FOG.
RME MVFR CIGS AND EXPECTED TO REMAIN THERE. ELM AND ITH HAVE A 5K
FT CIG WHICH SHOULD STAY MOST OF THE MORNING. COULD SCATTER
BRIEFLY MIDDAY. THIS MARINE DECK SHOULD PUSH EAST LATE MORNING
AHEAD OF A COLD FRONT WITH WINDS SHIFTING TO SW. SHOWERS WITH THE
COLD FRONT IN THE LATE AFTN BUT MOSTLY VFR. THIS EVENING LAKE
EFFECT SETS UP WITH A 280 FLOW. THIS MOSTLY AFFECTS RME AND MAYBE
SYR WITH SHOWERS AND MVFR. ITH AND BGM MAY ALSO HAVE MVFR CIGS
WITH THE CLOUDS OFF OF LAKE ERIE. THIS LAKE EFFECT LASTS MOST OF
THE NIGHT.
SE TO S WINDS AT 7 KTS OR LESS EARLY THIS MORNING. AROUND 14Z
WINDS SHIFT TO S TO SW AT AROUND 10 KTS. COULD BE SOME HIGHER
GUSTS TO 20 KTS IN THE AFTN. AROUND 21Z THE FRONT COMES THROUGH
SHIFTING WINDS TO W. WEST WINDS TONIGHT 5 TO 10 KTS.
OUTLOOK...
THU...VFR...BUT MVFR PSBL THU MRNG AT RME.
THU NGT...CONDITIONS DETERIORATING TO MVFR IN SHRA WITH CDFNT.
FRI...MVFR POSSIBLE EARLY MAINLY SRN NY AND NE PA...OTRW IMPRVMNT
TO VFR LATE OR FRIDAY EVE.
SAT...VFR.
SUN...MVFR IN SHRA.
&&
.CLIMATE...
NEAR RECORD LOW TEMPERATURES POSSIBLE SATURDAY MORNING OCTOBER
13TH. A COLD HIGH PRESSURE SYSTEM IS EXPECTED TO COVER THE REGION
BY SATURDAY MORNING AND COULD BRING WIDESPREAD FROST AND FREEZING
CONDITIONS TO THE REGION. RECORD LOWS THAT COULD BE CHALLENGED ARE
AS FOLLOWS:
RECORD (YEAR) SAT AM FORECAST LOW
GREATER BINGHAMTON AIRPORT 28 (1993) 30
SCRANTON/WILKES BARRE AIRPORT 29 (1993) 30
SYRACUSE AIRPORT 29 (2006) 31
ITHACA AIRPORT 25 (1964) 28
ELMIRA/CORNING AIRPORT 25 (1951) 26
ROME/GRIFFIS AIRPORT 26 (1993) 27
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN/PVN
SHORT TERM...DJN
LONG TERM...TAC
AVIATION...TAC
CLIMATE...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
652 AM EDT WED OCT 10 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA THIS AFTERNOON...BRINGING ANOTHER CHANCE OF SHOWERS.
BEHIND THE FRONT...LAKE EFFECT SHOWERS AND MUCH COOLER AIR WILL
AFFECT THE REGION TONIGHT AND THURSDAY MORNING FOR AREAS EAST OF
LAKE ONTARIO. OTHERWISE FOR THE REST OF THE AREA CHILLIER FALL
LIKE CONDITIONS WILL PREVAIL FOR THE REMAINDER OF THE WEEK. A
LARGE HIGH PRESSURE SYSTEM WILL SETTLE OVER THE REGION SATURDAY
MORNING WITH A CHANCE FOR WIDESPREAD FROST AND FREEZING
CONDITIONS.
&&
.NEAR TERM /THROUGH TONIGHT/...
KBGM 88D VWP SHOWS A LAYER OF SOUTH TO SOUTHWEST FLOW BETWEEN 2
AND 7 THOUSAND FEET ABOVE GROUND LEVEL IN ASSOCIATION WITH THE
SOUTHERLY FLOW AHEAD OF THE NEXT SIGNIFICANT UPPER LEVEL WAVE AND
SURFACE FRONT MOVING THROUGH THE GREAT LAKES REGION. THIS
SOUTHERLY FLOW WAS ADVECTING MOISTURE ABOVE A COOLER LAYER FROM
THE SFC TO 925 MB WHICH WAS SEEN WELL IN THE OBSERVATIONS AS A LOW-
LEVEL SOUTHEASTERLY SFC FLOW. SFC TEMPERATURES AND DEWPOINTS WERE
IN THE UPPER 40S AND LOWER 50S WITH DEWPOINTS A COUPLE DEGREES
LOWER. THE LATEST RAP MODEL ALSO HAD DEWPOINTS IN THE UPPER 40S
AT 925 MB. IN CONTRAST...ABOVE THIS LAYER...THERE WERE DEWPOINTS
RUNNING IN THE LOWER 50S AS PER MODEL SOUNDINGS. THIS WAS LEADING
TO SATURATION AND LO AND BEHOLD THE RADAR WAS SHOWG PATCHY DRIZZLE
MAINLY E OF A SYR-TOWANDA LINE FLOWING NORTH TO NORTHEAST IN
ASSOCIATION WITH THIS S-SW FLOW. IN ADDTN...CLOUD CIGS SUGGESTS
THAT THE MOUNTAINS IN THE POCONOS...CATSKILLS AND HIGHLANDS OF
NORTHERN PA ABOVE 1800 FEET WERE SOCKED IN WITH FOG. MOUNT POCONO
WAS 1/2SM FG...SO I SUSPECT FOG IS VERY PATCHY IN THE HIGH
TERRAIN. PUT PATCHY DENSE FOG IN ERN PART OF CWA IN GRIDS ABOVE
1800 FEET WHICH IS NOT MUCH...EXCEPT IN CATSKILLS. SINCE THE LOW-
LEVEL FLOW HAS WEAKENED WEST OF THIS CLOUD AND DRIZZLE LAYER (W OF
SYR-TOW) SKIES HAVE CLEARED. FOG PRODUCT SATELLITE IMAGE SUGGESTS
COOLER MARINE-LIKE CLOUD LAYER WILL STAY TO THE E OF THESE AREAS
OVERNIGHT. THIS IS SUPPORTED BY MODEL GUIDC FOR THE MOST PART.
THUS I WILL KEEP CLDS AND DRIZZLY/PATCHY HIGH ELEVATION FOG OUT
FINGER LAKES AND WEST OVERNIGHT
THE LOW-LEVEL SFC TO 925 MB FLOW PATTERN WILL RESPOND TO THE
APPROACHING GREAT LAKES SYSTEM THIS AM BY TURNING THE WINDS MORE
SWRLY WHICH WILL ADVECT THE DRIZZLY/LOW MOISTURE TO THE EAST INTO
ERN NY BY 18Z. THUS I MOVE THE PATCHY DRIZZLE AND FOG EAST OF THE
CATSKILLS BY LATE MORNING.
THEN WE BEGIN TO FEEL THE EFFECT OF THE SIGNIFICANT UPPER LEVEL
GREAT LAKE TROUGH AND ASSOCIATED LOW-LEVEL FRNT. THE PV LOVE
ASSOCIATED WITH THE UPPER LEVEL WAVE REACHES INTO NY AND NRN PA BY
18Z AND ACTUALLY DIGS INTO NY AND PA BY 03Z THIS EVENING. THIS IS
A REFLECTION OF THE STRONG LL COLD AIR ADVECTION. THIS PUSHES THE
850 MB FRONT TO ABT ROC-ELZ BY 18Z. THE 850 MB FRNT WILL THEN MOVE
EAST AND REACH UCA-BGM-TOW BY 21Z AND CATSKILLS/POCONOS BY 00Z
AND CLEAR ALL OF NE PA AND SE NY BY 03Z OR SO.
MODELS SEEM TO HAVE MOST OF THE PRECIP ALONG THE 850 MB FRONT
TODAY. THE PRECIP THEN FIZZLES AS IT WORKS E OF C NY AND NE PA. THEN
THE STRG COLD AIR ADVECTION BEHIND THE 850 MB FRNT TAKES OVER AND
LEADS TO PLENTY OF SC AND A SHARP DROP IN 850 MB TEMPS TO -4C
BTWN 6Z AND 12Z THU. LAKE ONTARIO TEMPERATURES ARE RUNNING ARND
16Z...WHICH GIVES A 20C DIFFERENTIAL. THIS IS EXTREME INSTABILITY.
THE LOW-LEVELS APPEAR TOO WARM ESPECIALLY IF ENUF SENSIBLE AND
LATENT HEATING TAKES PLACE FROM THE LAKE WATERS WHICH IS ASSUMED.
IN THIS CASE...IT WUD BE TOO WARM FOR ANY EARLY LAKE SNOWS AT THIS
POINT IN NC NY. HOWEVER...WILL HAVE LAKE EFFECT RAIN SHOWERS
DOWNWIND OF LAKE ONTARIO ON A 280 DEGREE FLOW TONIGHT.
COLLABORATED WITH KBUF WFO ON LAKE RAIN SHOWERS POSITIONING
TONIGHT VIA ISC GRIDS. REST OF CWA WILL SEE SOME LAKE CLOUDS BUT
LIKELY IT WILL REMAIN MOSTLY DRY TONIGHT.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
FOR THURSDAY...LAKE EFFECT SHOWERS RAPIDLY LIFT NORTHWARD INTO NRN
NY AS THE LOW-LEVE FLOW BACKS TO MORE W-SW IN ADVANCE OF THE NEXT
SHORT WAVE AS ASSOCIATED SFC FRNT REACHES THE ERN GREAT LAKES
THURSDAY. SINCE THE FLOW WILL BE MORE W-SW IT WILL DRY OUT SO I
SEE A LOT OF SUNSHINE DEVELOPING WITH SEASONABLY CHILLY FALL
TEMPERATURES IN THE 50S MOST AREAS.
LATER THURSDAY AND THURSDAY NIGHT...GFS...EURO...CMC AND NAM ALL
BRING DOWN A COLD FRONT FROM THE NORTH ASSOCIATED WITH THE
PASSAGE OF AN UPPER LEVEL WAVE ACROSS SOUTHEASTERN CANADA. THE
MODELS DIFFER IN TIMING A BIT WITH THE GFS THE FASTEST BRINGING THE
CLDS AND SHOWERS DOWN...THE NAM IS SLOWEST WITH THE EURO AND CMC A
COMPRIMISE. WILL GO WITH THE COMPRIMISE FOR NOW AS THERE IS
UNCERTAINTY. HAVE CHC TO LIKELY POPS FOR RAIN SHOWERS WITH AND
BEHIND FROPA THU NGT AND FRI AM. THEN I CAN SEE SOME LAKE EFFECT
RAIN SHOWERS AND CLOUDS LINGERING DOWNWIND FROM LAKE ONTARIO AT
LEAST THRU FRI AM. BY FRI PM AND FRI NGT...LARGE COLD HIGH
PRESSURE COVERS THE REGION. SKIES WILL CLEAR...WINDS WILL GO LIGHT
AND MANY OF OUR TREES ARE EITHER AT PEAK COLORS WITH QUITE A FEW
ALREADY DROPPED ALREADY. THEREFORE LITTLE TO NO EVAPOTRANSPIRATION.
THIS WILL KEEP DEWPOINTS DOWN SO I COULD SEE WIDESPREAD FREEZING
TEMPERATURES ENTIRE CWA SAT AM...MANY AREAS POTENTIALLY IN THE 20S.
COLDEST VALLEYS POSSIBLY EVEN FLIRTING WITH UPPER TEENS. KELM MEX
GUIDC SHOWING MIN OF 23 SAT WITH THE EURO GUIDC GOING FOR 25 AT
KELM. WE HAVE RURAL SPOTS THAT GET EVEN LOWER THAN ELM. ONLY FLY
IN THE OINTMENT IS IF THERE IS SOME PATCHY LAKE EFFECT CLOUDS
WHICH WUD HOLD TEMPS UP. IF IT HOLDS CLEAR WE LIKELY WILL HAVE A
WIDESPREAD FREEZE OR EVEN HARD FREEZE. RECORD MINIMUMS COULD BE
CHALLENGED. WILL HIGHLIGHT FREEZE POTENTIAL IN HWO FOR SATURDAY
AM.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
2 AM UPDATE...
LONG TERM LOOKS GOOD. MODELS SIMILAR. HIGH PRESSURE AND DRY
SATURDAY BUT BELOW NORMAL TEMPERATURES. WARMING SUNDAY BUT SHOWERS
WITH A WARM FRONT. COLD FRONT ON MONDAY WITH SHOWERS THEN A RIDGE
OF HIGH PRESSURE FOR TUESDAY AND WEDNESDAY. SLOW WARMING AS UPPER
LEVEL HEIGHTS RISE. ONLY MINOR CHANGES TO THE GRIDS.
PREVIOUS DISCUSSION...
PROGRESSIVE PTRN OVER THE MEDIUM RNG WITH S/WV`S PASSING EVERY
COUPLE OF DAYS W/ASSCD FNTL SYSTEMS. HIGH PRESSURE XPCTD TO BE
CNTRD OVER THE FCST AREA BY LATER FRI NGT...AND CLEARING SKIES MAY
ALLOW FOR AN AREA-WIDE FROST/FREEZE AND AN OFFICIAL END TO THE
GROWING SEASON. THE HIGH WILL SLIDE EWD TO THE CST BY SUNDAY
EVNG...WITH A VERY NICE DAY ANTICIPATED ON SAT. THE NXT S/WVS
APRCH FROM THE GTLAKES/OH VLY ON SUNDAY/SUN NGT WITH MORE -SHRA.
MON AND TUE LOOK DRY AT THIS TIME ALTHO A STRAY -SHRA CAN`T BE
RULED OUT SO WE RETAINED THE SLGT CHC POPS FOR THIS TIME. HPC
GUIDANCE LOOKED GOOD AND USED WITH ONLY MINOR TWEEKS.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
630 AM UPDATE...
A SOLID MARINE LAYER IS ACROSS THE SOUTHEAST TWO THIRDS OF THE
CWA. MORE LOW VFR CLOUDS APPROACHING FROM THE SW AND HIGH CLOUDS
FROM THE WEST. SOME SPOTTY DRIZZLE AND RAIN SHOWERS ALSO BEING
REPORTED AVP AND BGM EAST. RME...BGM...AVP WILL STAY UNDER A
IFR/MVFR DECK UNTIL AROUND 16Z. AVP JUST ABOVE 1K FT AND COULD
FALL FOR AN HOUR OR TWO 12 TO 14Z. BGM ALREADY VERY LOW IFR AND AT
FLIGHT MINIMUMS...ALSO EXPECTED SOME MVFR OR MAYBE IFR VSBY FOG.
RME MVFR CIGS AND EXPECTED TO REMAIN THERE. ELM AND ITH HAVE A 5K
FT CIG WHICH SHOULD STAY MOST OF THE MORNING. COULD SCATTER
BRIEFLY MIDDAY. THIS MARINE DECK SHOULD PUSH EAST LATE MORNING
AHEAD OF A COLD FRONT WITH WINDS SHIFTING TO SW. SHOWERS WITH THE
COLD FRONT IN THE LATE AFTN BUT MOSTLY VFR. THIS EVENING LAKE
EFFECT SETS UP WITH A 280 FLOW. THIS MOSTLY AFFECTS RME AND MAYBE
SYR WITH SHOWERS AND MVFR. ITH AND BGM MAY ALSO HAVE MVFR CIGS
WITH THE CLOUDS OFF OF LAKE ERIE. THIS LAKE EFFECT LASTS MOST OF
THE NIGHT.
SE TO S WINDS AT 7 KTS OR LESS EARLY THIS MORNING. AROUND 14Z
WINDS SHIFT TO S TO SW AT AROUND 10 KTS. COULD BE SOME HIGHER
GUSTS TO 20 KTS IN THE AFTN. AROUND 21Z THE FRONT COMES THROUGH
SHIFTING WINDS TO W. WEST WINDS TONIGHT 5 TO 10 KTS.
OUTLOOK...
THU...VFR...BUT MVFR PSBL THU MRNG AT RME.
THU NGT...CONDITIONS DETERIORATING TO MVFR IN SHRA WITH CDFNT.
FRI...MVFR POSSIBLE EARLY MAINLY SRN NY AND NE PA...OTRW IMPRVMNT
TO VFR LATE OR FRIDAY EVE.
SAT...VFR.
SUN...MVFR IN SHRA.
&&
.CLIMATE...
NEAR RECORD LOW TEMPERATURES POSSIBLE SATURDAY MORNING OCTOBER
13TH. A COLD HIGH PRESSURE SYSTEM IS EXPECTED TO COVER THE REGION
BY SATURDAY MORNING AND COULD BRING WIDESPREAD FROST AND FREEZING
CONDITIONS TO THE REGION. RECORD LOWS THAT COULD BE CHALLENGED ARE
AS FOLLOWS:
RECORD (YEAR) SAT AM FORECAST LOW
GREATER BINGHAMTON AIRPORT 28 (1993) 30
SCRANTON/WILKE BARRE AIRPORT 29 (1993) 30
SYRACUSE AIRPORT 29 (2006) 31
ITHACA AIRPORT 25 (1964) 28
ELMIRA/CORNING AIRPORT 25 (1951) 26
ROME/GRIFFIS AIRPORT 26 (1993) 27
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...TAC
AVIATION...TAC
CLIMATE...DJN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
505 AM EDT WED OCT 10 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA THIS AFTERNOON...BRINGING ANOTHER CHANCE OF SHOWERS.
BEHIND THE FRONT...LAKE EFFECT SHOWERS AND MUCH COOLER AIR WILL
AFFECT THE REGION TONIGHT AND THURSDAY MORNING FOR AREAS EAST OF
LAKE ONTARIO. OTHERWISE FOR THE REST OF THE AREA CHILLIER FALL
LIKE CONDITIONS WILL PREVAIL FOR THE REMAINDER OF THE WEEK. A
LARGE HIGH PRESSURE SYSTEM WILL SETTLE OVER THE REGION SATURDAY
MORNING WITH A CHANCE FOR WIDESPREAD FROST AND FREEZING
CONDITIONS.
&&
.NEAR TERM /THROUGH TONIGHT/...
KBGM 88D VWP SHOWS A LAYER OF SOUTH TO SOUTHWEST FLOW BETWEEN 2
AND 7 THOUSAND FEET ABOVE GROUND LEVEL IN ASSOCIATION WITH THE
SOUTHERLY FLOW AHEAD OF THE NEXT SIGNIFICANT UPPER LEVEL WAVE AND
SURFACE FRONT MOVING THROUGH THE GREAT LAKES REGION. THIS
SOUTHERLY FLOW WAS ADVECTING MOISTURE ABOVE A COOLER LAYER FROM
THE SFC TO 925 MB WHICH WAS SEEN WELL IN THE OBSERVATIONS AS A LOW-
LEVEL SOUTHEASTERLY SFC FLOW. SFC TEMPERATURES AND DEWPOINTS WERE
IN THE UPPER 40S AND LOWER 50S WITH DEWPOINTS A COUPLE DEGREES
LOWER. THE LATEST RAP MODEL ALSO HAD DEWPOINTS IN THE UPPER 40S
AT 925 MB. IN CONTRAST...ABOVE THIS LAYER...THERE WERE DEWPOINTS
RUNNING IN THE LOWER 50S AS PER MODEL SOUNDINGS. THIS WAS LEADING
TO SATURATION AND LO AND BEHOLD THE RADAR WAS SHOWG PATCHY DRIZZLE
MAINLY E OF A SYR-TOWANDA LINE FLOWING NORTH TO NORTHEAST IN
ASSOCIATION WITH THIS S-SW FLOW. IN ADDTN...CLOUD CIGS SUGGESTS
THAT THE MOUNTAINS IN THE POCONOS...CATSKILLS AND HIGHLANDS OF
NORTHERN PA ABOVE 1800 FEET WERE SOCKED IN WITH FOG. MOUNT POCONO
WAS 1/2SM FG...SO I SUSPECT FOG IS VERY PATCHY IN THE HIGH
TERRAIN. PUT PATCHY DENSE FOG IN ERN PART OF CWA IN GRIDS ABOVE
1800 FEET WHICH IS NOT MUCH...EXCEPT IN CATSKILLS. SINCE THE LOW-
LEVEL FLOW HAS WEAKENED WEST OF THIS CLOUD AND DRIZZLE LAYER (W OF
SYR-TOW) SKIES HAVE CLEARED. FOG PRODUCT SATELLITE IMAGE SUGGESTS
COOLER MARINE-LIKE CLOUD LAYER WILL STAY TO THE E OF THESE AREAS
OVERNIGHT. THIS IS SUPPORTED BY MODEL GUIDC FOR THE MOST PART.
THUS I WILL KEEP CLDS AND DRIZZLY/PATCHY HIGH ELEVATION FOG OUT
FINGER LAKES AND WEST OVERNIGHT
THE LOW-LEVEL SFC TO 925 MB FLOW PATTERN WILL RESPOND TO THE
APPROACHING GREAT LAKES SYSTEM THIS AM BY TURNING THE WINDS MORE
SWRLY WHICH WILL ADVECT THE DRIZZLY/LOW MOISTURE TO THE EAST INTO
ERN NY BY 18Z. THUS I MOVE THE PATCHY DRIZZLE AND FOG EAST OF THE
CATSKILLS BY LATE MORNING.
THEN WE BEGIN TO FEEL THE EFFECT OF THE SIGNIFICANT UPPER LEVEL
GREAT LAKE TROUGH AND ASSOCIATED LOW-LEVEL FRNT. THE PV LOVE
ASSOCIATED WITH THE UPPER LEVEL WAVE REACHES INTO NY AND NRN PA BY
18Z AND ACTUALLY DIGS INTO NY AND PA BY 03Z THIS EVENING. THIS IS
A REFLECTION OF THE STRONG LL COLD AIR ADVECTION. THIS PUSHES THE
850 MB FRONT TO ABT ROC-ELZ BY 18Z. THE 850 MB FRNT WILL THEN MOVE
EAST AND REACH UCA-BGM-TOW BY 21Z AND CATSKILLS/POCONOS BY 00Z
AND CLEAR ALL OF NE PA AND SE NY BY 03Z OR SO.
MODELS SEEM TO HAVE MOST OF THE PRECIP ALONG THE 850 MB FRONT
TODAY. THE PRECIP THEN FIZZLES AS IT WORKS E OF C NY AND NE PA. THEN
THE STRG COLD AIR ADVECTION BEHIND THE 850 MB FRNT TAKES OVER AND
LEADS TO PLENTY OF SC AND A SHARP DROP IN 850 MB TEMPS TO -4C
BTWN 6Z AND 12Z THU. LAKE ONTARIO TEMPERATURES ARE RUNNING ARND
16Z...WHICH GIVES A 20C DIFFERENTIAL. THIS IS EXTREME INSTABILITY.
THE LOW-LEVELS APPEAR TOO WARM ESPECIALLY IF ENUF SENSIBLE AND
LATENT HEATING TAKES PLACE FROM THE LAKE WATERS WHICH IS ASSUMED.
IN THIS CASE...IT WUD BE TOO WARM FOR ANY EARLY LAKE SNOWS AT THIS
POINT IN NC NY. HOWEVER...WILL HAVE LAKE EFFECT RAIN SHOWERS
DOWNWIND OF LAKE ONTARIO ON A 280 DEGREE FLOW TONIGHT.
COLLABORATED WITH KBUF WFO ON LAKE RAIN SHOWERS POSITIONING
TONIGHT VIA ISC GRIDS. REST OF CWA WILL SEE SOME LAKE CLOUDS BUT
LIKELY IT WILL REMAIN MOSTLY DRY TONIGHT.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
FOR THURSDAY...LAKE EFFECT SHOWERS RAPIDLY LIFT NORTHWARD INTO NRN
NY AS THE LOW-LEVE FLOW BACKS TO MORE W-SW IN ADVANCE OF THE NEXT
SHORT WAVE AS ASSOCIATED SFC FRNT REACHES THE ERN GREAT LAKES
THURSDAY. SINCE THE FLOW WILL BE MORE W-SW IT WILL DRY OUT SO I
SEE A LOT OF SUNSHINE DEVELOPING WITH SEASONABLY CHILLY FALL
TEMPERATURES IN THE 50S MOST AREAS.
LATER THURSDAY AND THURSDAY NIGHT...GFS...EURO...CMC AND NAM ALL
BRING DOWN A COLD FRONT FROM THE NORTH ASSOCIATED WITH THE
PASSAGE OF AN UPPER LEVEL WAVE ACROSS SOUTHEASTERN CANADA. THE
MODELS DIFFER IN TIMING A BIT WITH THE GFS THE FASTEST BRINGING THE
CLDS AND SHOWERS DOWN...THE NAM IS SLOWEST WITH THE EURO AND CMC A
COMPRIMISE. WILL GO WITH THE COMPRIMISE FOR NOW AS THERE IS
UNCERTAINTY. HAVE CHC TO LIKELY POPS FOR RAIN SHOWERS WITH AND
BEHIND FROPA THU NGT AND FRI AM. THEN I CAN SEE SOME LAKE EFFECT
RAIN SHOWERS AND CLOUDS LINGERING DOWNWIND FROM LAKE ONTARIO AT
LEAST THRU FRI AM. BY FRI PM AND FRI NGT...LARGE COLD HIGH
PRESSURE COVERS THE REGION. SKIES WILL CLEAR...WINDS WILL GO LIGHT
AND MANY OF OUR TREES ARE EITHER AT PEAK COLORS WITH QUITE A FEW
ALREADY DROPPED ALREADY. THEREFORE LITTLE TO NO EVAPOTRANSPIRATION.
THIS WILL KEEP DEWPOINTS DOWN SO I COULD SEE WIDESPREAD FREEZING
TEMPERATURES ENTIRE CWA SAT AM...MANY AREAS POTENTIALLY IN THE 20S.
COLDEST VALLEYS POSSIBLY EVEN FLIRTING WITH UPPER TEENS. KELM MEX
GUIDC SHOWING MIN OF 23 SAT WITH THE EURO GUIDC GOING FOR 25 AT
KELM. WE HAVE RURAL SPOTS THAT GET EVEN LOWER THAN ELM. ONLY FLY
IN THE OINTMENT IS IF THERE IS SOME PATCHY LAKE EFFECT CLOUDS
WHICH WUD HOLD TEMPS UP. IF IT HOLDS CLEAR WE LIKELY WILL HAVE A
WIDESPREAD FREEZE OR EVEN HARD FREEZE. RECORD MINIMUMS COULD BE
CHALLENGED. WILL HIGHLIGHT FREEZE POTENTIAL IN HWO FOR SATURDAY
AM.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
2 AM UPDATE...
LONG TERM LOOKS GOOD. MODELS SIMILAR. HIGH PRESSURE AND DRY
SATURDAY BUT BELOW NORMAL TEMPERATURES. WARMING SUNDAY BUT SHOWERS
WITH A WARM FRONT. COLD FRONT ON MONDAY WITH SHOWERS THEN A RIDGE
OF HIGH PRESSURE FOR TUESDAY AND WEDNESDAY. SLOW WARMING AS UPPER
LEVEL HEIGHTS RISE.
PREVIOUS DISCUSSION...
PROGRESSIVE PTRN OVER THE MEDIUM RNG WITH S/WV`S PASSING EVERY
COUPLE OF DAYS W/ASSCD FNTL SYSTEMS. HIGH PRESSURE XPCTD TO BE
CNTRD OVER THE FCST AREA BY LATER FRI NGT...AND CLEARING SKIES MAY
ALLOW FOR AN AREA-WIDE FROST/FREEZE AND AN OFFICIAL END TO THE
GROWING SEASON. THE HIGH WILL SLIDE EWD TO THE CST BY SUNDAY
EVNG...WITH A VERY NICE DAY ANTICIPATED ON SAT. THE NXT S/WVS
APRCH FROM THE GTLAKES/OH VLY ON SUNDAY/SUN NGT WITH MORE -SHRA.
MON AND TUE LOOK DRY AT THIS TIME ALTHO A STRAY -SHRA CAN`T BE
RULED OUT SO WE RETAINED THE SLGT CHC POPS FOR THIS TIME. HPC
GUIDANCE LOOKED GOOD AND USED WITH ONLY MINOR TWEEKS.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
130 AM UPDATE...
A SOLID MARINE LAYER IS ACROSS THE SOUTHEAST TWO THIRDS OF THE
CWA. SOME SPOTTY DRIZZLE ALSO BEING REPORTED. RME...BGM...AVP
WILL STAY UNDER A IFR/MVFR DECK UNTIL AROUND 14Z. AVP JUST ABOVE
1K FT AND WILL PROBABY FALL FOR AN HOUR OR TWO EITHER SIDE OF 12Z.
BGM ALREADY VERY LOW IFR AND AT FLIGHT MINIMUMS...ALSO EXPECTED TO
ADD SOME MVFR OR MAYBE IFR VSBY FOG TO THAT. RME MVFR CIGS AND
EXPECTED TO REMAIN THERE. LITTLE MOVEMENT TO THE CLOUD EDGE
EXPECTED BUT ITH ON THIS EDGE SO COULD HAVE A MVFR CIG OR BE
CLEAR. ELM HAVING CLEAR SKIES AND CALM SURFACE WINDS COULD DROP TO
IFR IN VALLEY FOG. CONFIDENCE LOW SO HEDGED WITH MVFR CIGS AND
VSBY 8 TO 12Z. THIS MARINE DECK SHOULD PUSH EAST LATE MORNING
AHEAD OF A COLD FRONT WITH WINDS SHIFTING TO SW. SHOWERS WITH THE
COLD FRONT IN THE LATE AFTN BUT MOSTLY VFR. THIS EVENING LAKE
EFFECT SETS UP WITH A 280 FLOW. THIS MOSTLY AFFECTS RME AND MAYBE
SYR WITH SHOWERS AND MVFR. ITH AND BGM MAY ALSO HAVE MVFR CIGS
WITH THE CLOUDS OFF OF LAKE ERIE.
SE TO S WINDS AT 7 KTS OR LESS EARLY THIS MORNING. AROUND 14Z
WINDS SHIFT TO S TO SW AT AROUND 10 KTS. COULD BE SOME HIGHER
GUSTS TO 20 KTS IN THE AFTN. AROUND 21Z THE FRONT COMES THROUGH
SHIFTING WINDS TO W.
OUTLOOK...
WED NGT...VFR...XCPT PSBL MVFR AT RME/SYR DUE TO LAKE CLDS/SHRA.
THU...VFR...BUT MVFR PSBL THU MRNG AT RME.
THU NGT...CONDITIONS DETERIORATING TO MVFR IN SHRA WITH CDFNT.
FRI...MVFR POSSIBLE EARLY MAINLY SRN NY AND NE PA...OTRW IMPRVMNT
TO VFR LATE OR FRIDAY EVE.
SAT...VFR.
SUN...MVFR IN SHRA.
&&
.CLIMATE...
NEAR RECORD LOW TEMPERATURES POSSIBLE SATURDAY MORNING OCTOBER
13TH. A COLD HIGH PRESSURE SYSTEM IS EXPECTED TO COVER THE REGION
BY SATURDAY MORNING AND COULD BRING WIDESPREAD FROST AND FREEZING
CONDITIONS TO THE REGION. RECORD LOWS THAT COULD BE CHALLENGED ARE
AS FOLLOWS:
RECORD (YEAR) SAT AM FORECAST LOW
GREATER BINGHAMTON AIRPORT 28 (1993) 30
SCRANTON/WILKE BARRE AIRPORT 29 (1993) 30
SYRACUSE AIRPORT 29 (2006) 31
ITHACA AIRPORT 25 (1964) 28
ELMIRA/CORNING AIRPORT 25 (1951) 26
ROME/GRIFFIS AIRPORT 26 (1993) 27
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...TAC
AVIATION...TAC
CLIMATE...DJN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
426 AM EDT WED OCT 10 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA THIS AFTERNOON...BRINGING ANOTHER CHANCE OF SHOWERS.
BEHIND THE FRONT...LAKE EFFECT SHOWERS AND MUCH COOLER AIR WILL
AFFECT THE REGION TONIGHT AND THURSDAY MORNING FOR AREAS EAST OF
LAKE ONTARIO. OTHERWISE FOR THE REST OF THE AREA CHILLIER FALL
LIKE CONDITIONS WILL PREVAIL FOR THE REMAINDER OF THE WEEK. A
LARGE HIGH PRESSURE SYSTEM WILL SETTLE OVER THE REGION SATURDAY
MORNING WITH A CHANCE FOR WIDESPREAD FROST AND FREEZING
CONDITIONS.
&&
.NEAR TERM /THROUGH TONIGHT/...
KBGM 88D VWP SHOWS A LAYER OF SOUTH TO SOUTHWEST FLOW BETWEEN 2
AND 7 THOUSAND FEET ABOVE GROUND LEVEL IN ASSOCIATION WITH THE
SOUTHERLY FLOW AHEAD OF THE NEXT SIGNIFICANT UPPER LEVEL WAVE AND
SURFACE FRONT MOVING THROUGH THE GREAT LAKES REGION. THIS
SOUTHERLY FLOW WAS ADVECTING MOISTURE ABOVE A COOLER LAYER FROM
THE SFC TO 925 MB WHICH WAS SEEN WELL IN THE OBSERVATIONS AS A LOW-
LEVEL SOUTHEASTERLY SFC FLOW. SFC TEMPERATURES AND DEWPOINTS WERE
IN THE UPPER 40S AND LOWER 50S WITH DEWPOINTS A COUPLE DEGREES
LOWER. THE LATEST RAP MODEL ALSO HAD DEWPOINTS IN THE UPPER 40S
AT 925 MB. IN CONTRAST...ABOVE THIS LAYER...THERE WERE DEWPOINTS
RUNNING IN THE LOWER 50S AS PER MODEL SOUNDINGS. THIS WAS LEADING
TO SATURATION AND LO AND BEHOLD THE RADAR WAS SHOWG PATCHY DRIZZLE
MAINLY E OF A SYR-TOWANDA LINE FLOWING NORTH TO NORTHEAST IN
ASSOCIATION WITH THIS S-SW FLOW. IN ADDTN...CLOUD CIGS SUGGESTS
THAT THE MOUNTAINS IN THE POCONOS...CATSKILLS AND HIGHLANDS OF
NORTHERN PA ABOVE 1800 FEET WERE SOCKED IN WITH FOG. MOUNT POCONO
WAS 1/2SM FG...SO I SUSPECT FOG IS VERY PATCHY IN THE HIGH
TERRAIN. PUT PATCHY DENSE FOG IN ERN PART OF CWA IN GRIDS ABOVE
1800 FEET WHICH IS NOT MUCH...EXCEPT IN CATSKILLS. SINCE THE LOW-
LEVEL FLOW HAS WEAKENED WEST OF THIS CLOUD AND DRIZZLE LAYER (W OF
SYR-TOW) SKIES HAVE CLEARED. FOG PRODUCT SATELLITE IMAGE SUGGESTS
COOLER MARINE-LIKE CLOUD LAYER WILL STAY TO THE E OF THESE AREAS
OVERNIGHT. THIS IS SUPPORTED BY MODEL GUIDC FOR THE MOST PART.
THUS I WILL KEEP CLDS AND DRIZZLY/PATCHY HIGH ELEVATION FOG OUT
FINGER LAKES AND WEST OVERNIGHT
THE LOW-LEVEL SFC TO 925 MB FLOW PATTERN WILL RESPOND TO THE
APPROACHING GREAT LAKES SYSTEM THIS AM BY TURNING THE WINDS MORE
SWRLY WHICH WILL ADVECT THE DRIZZLY/LOW MOISTURE TO THE EAST INTO
ERN NY BY 18Z. THUS I MOVE THE PATCHY DRIZZLE AND FOG EAST OF THE
CATSKILLS BY LATE MORNING.
THEN WE BEGIN TO FEEL THE EFFECT OF THE SIGNIFICANT UPPER LEVEL
GREAT LAKE TROUGH AND ASSOCIATED LOW-LEVEL FRNT. THE PV LOVE
ASSOCIATED WITH THE UPPER LEVEL WAVE REACHES INTO NY AND NRN PA BY
18Z AND ACTUALLY DIGS INTO NY AND PA BY 03Z THIS EVENING. THIS IS
A REFLECTION OF THE STRONG LL COLD AIR ADVECTION. THIS PUSHES THE
850 MB FRONT TO ABT ROC-ELZ BY 18Z. THE 850 MB FRNT WILL THEN MOVE
EAST AND REACH UCA-BGM-TOW BY 21Z AND CATSKILLS/POCONOS BY 00Z
AND CLEAR ALL OF NE PA AND SE NY BY 03Z OR SO.
MODELS SEEM TO HAVE MOST OF THE PRECIP ALONG THE 850 MB FRONT
TODAY. THE PRECIP THEN FIZZLES AS IT WORKS E OF C NY AND NE PA. THEN
THE STRG COLD AIR ADVECTION BEHIND THE 850 MB FRNT TAKES OVER AND
LEADS TO PLENTY OF SC AND A SHARP DROP IN 850 MB TEMPS TO -4C
BTWN 6Z AND 12Z THU. LAKE ONTARIO TEMPERATURES ARE RUNNING ARND
16Z...WHICH GIVES A 20C DIFFERENTIAL. THIS IS EXTREME INSTABILITY.
THE LOW-LEVELS APPEAR TOO WARM ESPECIALLY IF ENUF SENSIBLE AND
LATENT HEATING TAKES PLACE FROM THE LAKE WATERS WHICH IS ASSUMED.
IN THIS CASE...IT WUD BE TOO WARM FOR ANY EARLY LAKE SNOWS AT THIS
POINT IN NC NY. HOWEVER...WILL HAVE LAKE EFFECT RAIN SHOWERS
DOWNWIND OF LAKE ONTARIO ON A 280 DEGREE FLOW TONIGHT.
COLLABORATED WITH KBUF WFO ON LAKE RAIN SHOWERS POSITIONING
TONIGHT VIA ISC GRIDS. REST OF CWA WILL SEE SOME LAKE CLOUDS BUT
LIKELY IT WILL REMAIN MOSTLY DRY TONIGHT.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
FOR THURSDAY...LAKE EFFECT SHOWERS RAPIDLY LIFT NORTHWARD INTO NRN
NY AS THE LOW-LEVE FLOW BACKS TO MORE W-SW IN ADVANCE OF THE NEXT
SHORT WAVE AS ASSOCIATED SFC FRNT REACHES THE ERN GREAT LAKES
THURSDAY. SINCE THE FLOW WILL BE MORE W-SW IT WILL DRY OUT SO I
SEE A LOT OF SUNSHINE DEVELOPING WITH SEASONABLY CHILLY FALL
TEMPERATURES IN THE 50S MOST AREAS.
LATER THURSDAY AND THURSDAY NIGHT...GFS...EURO...CMC AND NAM ALL
BRING DOWN A COLD FRONT FROM THE NORTH ASSOCIATED WITH THE
PASSAGE OF AN UPPER LEVEL WAVE ACROSS SOUTHEASTERN CANADA. THE
MODELS DIFFER IN TIMING A BIT WITH THE GFS THE FASTEST BRINGING THE
CLDS AND SHOWERS DOWN...THE NAM IS SLOWEST WITH THE EURO AND CMC A
COMPRIMISE. WILL GO WITH THE COMPRIMISE FOR NOW AS THERE IS
UNCERTAINTY. HAVE CHC TO LIKELY POPS FOR RAIN SHOWERS WITH AND
BEHIND FROPA THU NGT AND FRI AM. THEN I CAN SEE SOME LAKE EFFECT
RAIN SHOWERS AND CLOUDS LINGERING DOWNWIND FROM LAKE ONTARIO AT
LEAST THRU FRI AM. BY FRI PM AND FRI NGT...LARGE COLD HIGH
PRESSURE COVERS THE REGION. SKIES WILL CLEAR...WINDS WILL GO LIGHT
AND MANY OF OUR TREES ARE EITHER AT PEAK COLORS WITH QUITE A FEW
ALREADY DROPPED ALREADY. THEREFORE LITTLE TO NO EVAPOTRANSPIRATION.
THIS WILL KEEP DEWPOINTS DOWN SO I COULD SEE WIDESPREAD FREEZING
TEMPERATURES ENTIRE CWA SAT AM...MANY AREAS POTENTIALLY IN THE 20S.
COLDEST VALLEYS POSSIBLY EVEN FLIRTING WITH UPPER TEENS. KELM MEX
GUIDC SHOWING MIN OF 23 SAT WITH THE EURO GUIDC GOING FOR 25 AT
KELM. WE HAVE RURAL SPOTS THAT GET EVEN LOWER THAN ELM. ONLY FLY
IN THE OINTMENT IS IF THERE IS SOME PATCHY LAKE EFFECT CLOUDS
WHICH WUD HOLD TEMPS UP. IF IT HOLDS CLEAR WE LIKELY WILL HAVE A
WIDESPREAD FREEZE OR EVEN HARD FREEZE. RECORD MINIMUMS COULD BE
CHALLENGED. WILL HIGHLIGHT FREEZE POTENTIAL IN HWO FOR SATURDAY
AM.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
2 AM UPDATE...
LONG TERM LOOKS GOOD. MODELS SIMILAR. HIGH PRESSURE AND DRY
SATURDAY BUT BELOW NORMAL TEMPERATURES. WARMING SUNDAY BUT SHOWERS
WITH A WARM FRONT. COLD FRONT ON MONDAY WITH SHOWERS THEN A RIDGE
OF HIGH PRESSURE FOR TUESDAY AND WEDNESDAY. SLOW WARMING AS UPPER
LEVEL HEIGHTS RISE.
PREVIOUS DISCUSSION...
PROGRESSIVE PTRN OVER THE MEDIUM RNG WITH S/WV`S PASSING EVERY
COUPLE OF DAYS W/ASSCD FNTL SYSTEMS. HIGH PRESSURE XPCTD TO BE
CNTRD OVER THE FCST AREA BY LATER FRI NGT...AND CLEARING SKIES MAY
ALLOW FOR AN AREA-WIDE FROST/FREEZE AND AN OFFICIAL END TO THE
GROWING SEASON. THE HIGH WILL SLIDE EWD TO THE CST BY SUNDAY
EVNG...WITH A VERY NICE DAY ANTICIPATED ON SAT. THE NXT S/WVS
APRCH FROM THE GTLAKES/OH VLY ON SUNDAY/SUN NGT WITH MORE -SHRA.
MON AND TUE LOOK DRY AT THIS TIME ALTHO A STRAY -SHRA CAN`T BE
RULED OUT SO WE RETAINED THE SLGT CHC POPS FOR THIS TIME. HPC
GUIDANCE LOOKED GOOD AND USED WITH ONLY MINOR TWEEKS.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
130 AM UPDATE...
A SOLID MARINE LAYER IS ACROSS THE SOUTHEAST TWO THIRDS OF THE
CWA. SOME SPOTTY DRIZZLE ALSO BEING REPORTED. RME...BGM...AVP
WILL STAY UNDER A IFR/MVFR DECK UNTIL AROUND 14Z. AVP JUST ABOVE
1K FT AND WILL PROBABY FALL FOR AN HOUR OR TWO EITHER SIDE OF 12Z.
BGM ALREADY VERY LOW IFR AND AT FLIGHT MINIMUMS...ALSO EXPECTED TO
ADD SOME MVFR OR MAYBE IFR VSBY FOG TO THAT. RME MVFR CIGS AND
EXPECTED TO REMAIN THERE. LITTLE MOVEMENT TO THE CLOUD EDGE
EXPECTED BUT ITH ON THIS EDGE SO COULD HAVE A MVFR CIG OR BE
CLEAR. ELM HAVING CLEAR SKIES AND CALM SURFACE WINDS COULD DROP TO
IFR IN VALLEY FOG. CONFIDENCE LOW SO HEDGED WITH MVFR CIGS AND
VSBY 8 TO 12Z. THIS MARINE DECK SHOULD PUSH EAST LATE MORNING
AHEAD OF A COLD FRONT WITH WINDS SHIFTING TO SW. SHOWERS WITH THE
COLD FRONT IN THE LATE AFTN BUT MOSTLY VFR. THIS EVENING LAKE
EFFECT SETS UP WITH A 280 FLOW. THIS MOSTLY AFFECTS RME AND MAYBE
SYR WITH SHOWERS AND MVFR. ITH AND BGM MAY ALSO HAVE MVFR CIGS
WITH THE CLOUDS OFF OF LAKE ERIE.
SE TO S WINDS AT 7 KTS OR LESS EARLY THIS MORNING. AROUND 14Z
WINDS SHIFT TO S TO SW AT AROUND 10 KTS. COULD BE SOME HIGHER
GUSTS TO 20 KTS IN THE AFTN. AROUND 21Z THE FRONT COMES THROUGH
SHIFTING WINDS TO W.
OUTLOOK...
WED NGT...VFR...XCPT PSBL MVFR AT RME/SYR DUE TO LAKE CLDS/SHRA.
THU...VFR...BUT MVFR PSBL THU MRNG AT RME.
THU NGT...CONDITIONS DETERIORATING TO MVFR IN SHRA WITH CDFNT.
FRI...MVFR POSSIBLE EARLY MAINLY SRN NY AND NE PA...OTRW IMPRVMNT
TO VFR LATE OR FRIDAY EVE.
SAT...VFR.
SUN...MVFR IN SHRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...TAC
AVIATION...TAC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
246 AM EDT WED OCT 10 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA THIS AFTERNOON...BRINGING ANOTHER CHANCE OF SHOWERS.
BEHIND THE FRONT...LAKE EFFECT SHOWERS AND MUCH COOLER AIR WILL
AFFECT THE REGION TONIGHT AND THURSDAY MORNING FOR AREAS EAST OF
LAKE ONTARIO. OTHERWISE FOR THE REST OF THE AREA CHILLIER FALL
LIKE CONDITIONS WILL PREVAIL FOR THE REMAINDER OF THE WEEK. A
LARGE HIGH PRESSURE SYSTEM WILL SETTLE OVER THE REGION SATURDAY
MORNING WITH A CHANCE FOR WIDESPREAD FROST AND FREEZING
CONDITIONS.
&&
.NEAR TERM /THROUGH TONIGHT/...
KBGM 88D VWP SHOWS A LAYER OF SOUTH TO SOUTHWEST FLOW BETWEEN 2
AND 7 THOUSAND FEET ABOVE GROUND LEVEL IN ASSOCIATION WITH THE
SOUTHERLY FLOW AHEAD OF THE NEXT SIGNIFICANT UPPER LEVEL WAVE AND
SURFACE FRONT MOVING THROUGH THE GREAT LAKES REGION. THIS
SOUTHERLY FLOW WAS ADVECTING MOISTURE ABOVE A COOLER LAYER FROM
THE SFC TO 925 MB WHICH WAS SEEN WELL IN THE OBSERVATIONS AS A LOW-
LEVEL SOUTHEASTERLY SFC FLOW. SFC TEMPERATURES AND DEWPOINTS WERE
IN THE UPPER 40S AND LOWER 50S WITH DEWPOINTS A COUPLE DEGREES
LOWER. THE LATEST RAP MODEL ALSO HAD DEWPOINTS IN THE UPPER 40S
AT 925 MB. IN CONTRAST...ABOVE THIS LAYER...THERE WERE DEWPOINTS
RUNNING IN THE LOWER 50S AS PER MODEL SOUNDINGS. THIS WAS LEADING
TO SATURATION AND LO AND BEHOLD THE RADAR WAS SHOWG PATCHY DRIZZLE
MAINLY E OF A SYR-TOWANDA LINE FLOWING NORTH TO NORTHEAST IN
ASSOCIATION WITH THIS S-SW FLOW. IN ADDTN...CLOUD CIGS SUGGESTS
THAT THE MOUNTAINS IN THE POCONOS...CATSKILLS AND HIGHLANDS OF
NORTHERN PA ABOVE 1800 FEET WERE SOCKED IN WITH FOG. MOUNT POCONO
WAS 1/2SM FG...SO I SUSPECT FOG IS VERY PATCHY IN THE HIGH
TERRAIN. PUT PATCHY DENSE FOG IN ERN PART OF CWA IN GRIDS ABOVE
1800 FEET WHICH IS NOT MUCH...EXCEPT IN CATSKILLS. SINCE THE LOW-
LEVEL FLOW HAS WEAKENED WEST OF THIS CLOUD AND DRIZZLE LAYER (W OF
SYR-TOW) SKIES HAVE CLEARED. FOG PRODUCT SATELLITE IMAGE SUGGESTS
COOLER MARINE-LIKE CLOUD LAYER WILL STAY TO THE E OF THESE AREAS
OVERNIGHT. THIS IS SUPPORTED BY MODEL GUIDC FOR THE MOST PART.
THUS I WILL KEEP CLDS AND DRIZZLY/PATCHY HIGH ELEVATION FOG OUT
FINGER LAKES AND WEST OVERNIGHT
THE LOW-LEVEL SFC TO 925 MB FLOW PATTERN WILL RESPOND TO THE
APPROACHING GREAT LAKES SYSTEM THIS AM BY TURNING THE WINDS MORE
SWRLY WHICH WILL ADVECT THE DRIZZLY/LOW MOISTURE TO THE EAST INTO
ERN NY BY 18Z. THUS I MOVE THE PATCHY DRIZZLE AND FOG EAST OF THE
CATSKILLS BY LATE MORNING.
THEN WE BEGIN TO FEEL THE EFFECT OF THE SIGNIFICANT UPPER LEVEL
GREAT LAKE TROUGH AND ASSOCIATED LOW-LEVEL FRNT. THE PV LOVE
ASSOCIATED WITH THE UPPER LEVEL WAVE REACHES INTO NY AND NRN PA BY
18Z AND ACTUALLY DIGS INTO NY AND PA BY 03Z THIS EVENING. THIS IS
A REFLECTION OF THE STRONG LL COLD AIR ADVECTION. THIS PUSHES THE
850 MB FRONT TO ABT ROC-ELZ BY 18Z. THE 850 MB FRNT WILL THEN MOVE
EAST AND REACH UCA-BGM-TOW BY 21Z AND CATSKILLS/POCONOS BY 00Z
AND CLEAR ALL OF NE PA AND SE NY BY 03Z OR SO.
MODELS SEEM TO HAVE MOST OF THE PRECIP ALONG THE 850 MB FRONT
TODAY. THE PRECIP THEN FIZZLES AS IT WORKS E OF C NY AND NE PA. THEN
THE STRG COLD AIR ADVECTION BEHIND THE 850 MB FRNT TAKES OVER AND
LEADS TO PLENTY OF SC AND A SHARP DROP IN 850 MB TEMPS TO -4C
BTWN 6Z AND 12Z THU. LAKE ONTARIO TEMPERATURES ARE RUNNING ARND
16Z...WHICH GIVES A 20C DIFFERENTIAL. THIS IS EXTREME INSTABILITY.
THE LOW-LEVELS APPEAR TOO WARM ESPECIALLY IF ENUF SENSIBLE AND
LATENT HEATING TAKES PLACE FROM THE LAKE WATERS WHICH IS ASSUMED.
IN THIS CASE...IT WUD BE TOO WARM FOR ANY EARLY LAKE SNOWS AT THIS
POINT IN NC NY. HOWEVER...WILL HAVE LAKE EFFECT RAIN SHOWERS
DOWNWIND OF LAKE ONTARIO ON A 280 DEGREE FLOW TONIGHT.
COLLABORATED WITH KBUF WFO ON LAKE RAIN SHOWERS POSITIONING
TONIGHT VIA ISC GRIDS. REST OF CWA WILL SEE SOME LAKE CLOUDS BUT
LIKELY IT WILL REMAIN MOSTLY DRY TONIGHT.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
330 PM UPDATE...CDFNT WL COME RACING THRU ON WED WITH SCTD
SHOWERS ACCOMPANYING THE BNDRY THRU THE CWA. H8 TEMPS RISE AHD OF
THIS FNT TO +5C WITH WAA AHD OF THE BNDRY WHICH WUD YIELD HIGHS IN
THE LWR 60S. WINDS WILL GUST OUT OF THE WEST BHND THE FNT.
LK EFFECT SHOWERS WL KICK IN ON WED NGT WITH INSTABILITY PRESENT
BHND THE FNT. STEERING LAYER FLOW OF 270-290 DEGREES WL SPREAD SCTD
SHOWERS INTO NWRN ONEIDA/NRN MADISON AND NRN ONONDAGA COUNTIES WITH
QPF AMNTS OF 0.10-0.20 INCHES. AFT 06Z WINDS WL WEAKEN AND VARY FM
WRLY TO NWRLY AND AREA OF SHOWERS MAY EXTND INTO NRN OTSEGO CNTYS BY
MRNG.
DRG THE DAY THURSDAY, WINDS SHIFT ARND TO A SWRLY DIRECTION BRINGING
LINGERING LK EFFECT SHOWERS OUT OF THE CWA. NEXT IN A SERIES OF
CDFNTS WL APPCH THE AREA THUR NGT INTO FRI MRNG. EXTENSIVE CLD CVR
WL BE PRESENT AHD OF THE FNT...KEEPING OVRNT MINS ARND 40F. CHC POPS
WL MV INTO THE NRN ZONES BY 12Z FRI...CONTG IN NY STATE THRU 18Z BFR
FADING OUT AS UL WV WEAKENS AND MOST OF THE LIFT GOES OFF TO THE
NORTH IN CANADA AND SHEARS ITSELF OUT. SKIES WL CLR DRG THE AFTN AS
SFC HIPRES BUILDS OVR TOP OF THE AREA ON FRIDAY.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
2 AM UPDATE...
LONG TERM LOOKS GOOD. MODELS SIMILAR. HIGH PRESSURE AND DRY
SATURDAY BUT BELOW NORMAL TEMPERATURES. WARMING SUNDAY BUT SHOWERS
WITH A WARM FRONT. COLD FRONT ON MONDAY WITH SHOWERS THEN A RIDGE
OF HIGH PRESSURE FOR TUESDAY AND WEDNESDAY. SLOW WARMING AS UPPER
LEVEL HEIGHTS RISE.
PREVIOUS DISCUSSION...
PROGRESSIVE PTRN OVER THE MEDIUM RNG WITH S/WV`S PASSING EVERY
COUPLE OF DAYS W/ASSCD FNTL SYSTEMS. HIGH PRESSURE XPCTD TO BE
CNTRD OVER THE FCST AREA BY LATER FRI NGT...AND CLEARING SKIES MAY
ALLOW FOR AN AREA-WIDE FROST/FREEZE AND AN OFFICIAL END TO THE
GROWING SEASON. THE HIGH WILL SLIDE EWD TO THE CST BY SUNDAY
EVNG...WITH A VERY NICE DAY ANTICIPATED ON SAT. THE NXT S/WVS
APRCH FROM THE GTLAKES/OH VLY ON SUNDAY/SUN NGT WITH MORE -SHRA.
MON AND TUE LOOK DRY AT THIS TIME ALTHO A STRAY -SHRA CAN`T BE
RULED OUT SO WE RETAINED THE SLGT CHC POPS FOR THIS TIME. HPC
GUIDANCE LOOKED GOOD AND USED WITH ONLY MINOR TWEEKS.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
130 AM UPDATE...
A SOLID MARINE LAYER IS ACROSS THE SOUTHEAST TWO THIRDS OF THE
CWA. SOME SPOTTY DRIZZLE ALSO BEING REPORTED. RME...BGM...AVP
WILL STAY UNDER A IFR/MVFR DECK UNTIL AROUND 14Z. AVP JUST ABOVE
1K FT AND WILL PROBABY FALL FOR AN HOUR OR TWO EITHER SIDE OF 12Z.
BGM ALREADY VERY LOW IFR AND AT FLIGHT MINIMUMS...ALSO EXPECTED TO
ADD SOME MVFR OR MAYBE IFR VSBY FOG TO THAT. RME MVFR CIGS AND
EXPECTED TO REMAIN THERE. LITTLE MOVEMENT TO THE CLOUD EDGE
EXPECTED BUT ITH ON THIS EDGE SO COULD HAVE A MVFR CIG OR BE
CLEAR. ELM HAVING CLEAR SKIES AND CALM SURFACE WINDS COULD DROP TO
IFR IN VALLEY FOG. CONFIDENCE LOW SO HEDGED WITH MVFR CIGS AND
VSBY 8 TO 12Z. THIS MARINE DECK SHOULD PUSH EAST LATE MORNING
AHEAD OF A COLD FRONT WITH WINDS SHIFTING TO SW. SHOWERS WITH THE
COLD FRONT IN THE LATE AFTN BUT MOSTLY VFR. THIS EVENING LAKE
EFFECT SETS UP WITH A 280 FLOW. THIS MOSTLY AFFECTS RME AND MAYBE
SYR WITH SHOWERS AND MVFR. ITH AND BGM MAY ALSO HAVE MVFR CIGS
WITH THE CLOUDS OFF OF LAKE ERIE.
SE TO S WINDS AT 7 KTS OR LESS EARLY THIS MORNING. AROUND 14Z
WINDS SHIFT TO S TO SW AT AROUND 10 KTS. COULD BE SOME HIGHER
GUSTS TO 20 KTS IN THE AFTN. AROUND 21Z THE FRONT COMES THROUGH
SHIFTING WINDS TO W.
OUTLOOK...
WED NGT...VFR...XCPT PSBL MVFR AT RME/SYR DUE TO LAKE CLDS/SHRA.
THU...VFR...BUT MVFR PSBL THU MRNG AT RME.
THU NGT...CONDITIONS DETERIORATING TO MVFR IN SHRA WITH CDFNT.
FRI...MVFR POSSIBLE EARLY MAINLY SRN NY AND NE PA...OTRW IMPRVMNT
TO VFR LATE OR FRIDAY EVE.
SAT...VFR.
SUN...MVFR IN SHRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...PVN
LONG TERM...TAC
AVIATION...TAC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
212 AM EDT WED OCT 10 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA TODAY AND THIS EVENING...BRINGING ANOTHER CHANCE OF SHOWERS.
BEHIND THE FRONT...LAKE EFFECT SHOWERS AND MUCH COOLER AIR WILL
AFFECT THE REGION THURSDAY MORNING FOR AREAS EAST OF LAKE ONTARIO.
OTHERWISE THE REST OF THE AREA CHILLIER FALL-LIKE CONDITIONS WILL
PREVAIL FOR THE REMAINDER OF THE WEEK. A LARGE HIGH PRESSURE
SYSTEM WILL SETTLE OVER THE REGION BY SATURDAY MORNING WITH A
CHANCE FOR WIDESPREAD FROST AND FREEZING CONDITIONS.
&&
.NEAR TERM /THROUGH TONIGHT/...
KBGM 88D VWP SHOWS A LAYER OF SOUTH TO SOUTHWEST FLOW BETWEEN 2
AND 7 THOUSAND FEET ABOVE GROUND LEVEL IN ASSOCIATION WITH THE
SOUTHERLY FLOW AHEAD OF THE NEXT SIGNIFICANT UPPER LEVEL WAVE AND
SURFACE FRONT MOVING THROUGH THE GREAT LAKES REGION. THIS
SOUTHERLY FLOW WAS ADVECTING MOISTURE ABOVE A COOLER LAYER FROM
THE SFC TO 925 MB WHICH WAS SEEN WELL IN THE OBSERVATIONS AS A LOW-
LEVEL SOUTHEASTERLY SFC FLOW. SFC TEMPERATURES AND DEWPOINTS WERE
IN THE UPPER 40S AND LOWER 50S WITH DEWPOINTS A COUPLE DEGREES
LOWER. THE LATEST RAP MODEL ALSO HAD DEWPOINTS IN THE UPPER 40S
AT 925 MB. IN CONTRAST...ABOVE THIS LAYER...THERE WERE DEWPOINTS
RUNNING IN THE LOWER 50S AS PER MODEL SOUNDINGS. THIS WAS LEADING
TO SATURATION AND LO AND BEHOLD THE RADAR WAS SHOWG PATCHY DRIZZLE
MAINLY E OF A SYR-TOWANDA LINE FLOWING NORTH TO NORTHEAST IN
ASSOCIATION WITH THIS S-SW FLOW. IN ADDTN...CLOUD CIGS SUGGESTS
THAT THE MOUNTAINS IN THE POCONOS...CATSKILLS AND HIGHLANDS OF
NORTHERN PA ABOVE 1800 FEET WERE SOCKED IN WITH FOG. MOUNT POCONO
WAS 1/2SM FG...SO I SUSPECT FOG IS VERY PATCHY IN THE HIGH
TERRAIN. PUT PATCHY DENSE FOG IN ERN PART OF CWA IN GRIDS ABOVE
1800 FEET WHICH IS NOT MUCH...EXCEPT IN CATSKILLS. SINCE THE LOW-
LEVEL FLOW HAS WEAKENED WEST OF THIS CLOUD AND DRIZZLE LAYER (W OF
SYR-TOW) SKIES HAVE CLEARED. FOG PRODUCT SATELLITE IMAGE SUGGESTS
COOLER MARINE-LIKE CLOUD LAYER WILL STAY TO THE E OF THESE AREAS
OVERNIGHT. THIS IS SUPPORTED BY MODEL GUIDC FOR THE MOST PART.
THUS I WILL KEEP CLDS AND DRIZZLY/PATCHY HIGH ELEVATION FOG OUT
FINGER LAKES AND WEST OVERNIGHT
THE LOW-LEVEL SFC TO 925 MB FLOW PATTERN WILL RESPOND TO THE
APPROACHING GREAT LAKES SYSTEM THIS AM BY TURNING THE WINDS MORE
SWRLY WHICH WILL ADVECT THE DRIZZLY/LOW MOISTURE TO THE EAST INTO
ERN NY BY 18Z. THUS I MOVE THE PATCHY DRIZZLE AND FOG EAST OF THE
CATSKILLS BY LATE MORNING.
THEN WE BEGIN TO FEEL THE EFFECT OF THE SIGNIFICANT UPPER LEVEL
GREAT LAKE TROUGH AND ASSOCIATED LOW-LEVEL FRNT. THE PV LOVE
ASSOCIATED WITH THE UPPER LEVEL WAVE REACHES INTO NY AND NRN PA BY
18Z AND ACTUALLY DIGS INTO NY AND PA BY 03Z THIS EVENING. THIS IS
A REFLECTION OF THE STRONG LL COLD AIR ADVECTION. THIS PUSHES THE
850 MB FRONT TO ABT ROC-ELZ BY 18Z. THE 850 MB FRNT WILL THEN MOVE
EAST AND REACH UCA-BGM-TOW BY 21Z AND CATSKILLS/POCONOS BY 00Z
AND CLEAR ALL OF NE PA AND SE NY BY 03Z OR SO.
MODELS SEEM TO HAVE MOST OF THE PRECIP ALONG THE 850 MB FRONT
TODAY. THE PRECIP THEN FIZZLES AS IT WORKS E OF C NY AND NE PA. THEN
THE STRG COLD AIR ADVECTION BEHIND THE 850 MB FRNT TAKES OVER AND LEADS
TO PLENTY OF SC AND A SHARP DROP IN 850 MB TEMPS TO -4C BTWN 6Z
AND 12Z THU. LAKE ONTARIO TEMPERATURES ARE RUNNING ARND
16Z...WHICH GIVES A 20C DIFFERENTIAL. THIS IS EXTREME INSTABILITY.
THE LOW-LEVELS APPEAR TOO WARM ESPECIALLY IF ENUF SENSIBLE AND
LATENT HEATING TAKES PLACE FROM THE LAKE WATERS WHICH IS ASSUMED.
IN THIS CASE...IT WUD BE TOO WARM FOR ANY EARLY LAKE SNOWS AT THIS
POINT IN NC NY. HOWEVER...WILL HAVE LAKE EFFECT RAIN SHOWERS
DOWNWIND OF LAKE ONTARIO ON A 280 DEGREE FLOW TONIGHT.
COLLABORATED WITH KBUF WFO ON LAKE RAIN SHOWERS POSITIONING
TONIGHT VIA ISC GRIDS. REST OF CWA WILL SEE SOME LAKE CLOUDS BUT
LIKELY IT WILL REMAIN MOSTLY DRY TONIGHT.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
330 PM UPDATE...CDFNT WL COME RACING THRU ON WED WITH SCTD
SHOWERS ACCOMPANYING THE BNDRY THRU THE CWA. H8 TEMPS RISE AHD OF
THIS FNT TO +5C WITH WAA AHD OF THE BNDRY WHICH WUD YIELD HIGHS IN
THE LWR 60S. WINDS WILL GUST OUT OF THE WEST BHND THE FNT.
LK EFFECT SHOWERS WL KICK IN ON WED NGT WITH INSTABILITY PRESENT
BHND THE FNT. STEERING LAYER FLOW OF 270-290 DEGREES WL SPREAD SCTD
SHOWERS INTO NWRN ONEIDA/NRN MADISON AND NRN ONONDAGA COUNTIES WITH
QPF AMNTS OF 0.10-0.20 INCHES. AFT 06Z WINDS WL WEAKEN AND VARY FM
WRLY TO NWRLY AND AREA OF SHOWERS MAY EXTND INTO NRN OTSEGO CNTYS BY
MRNG.
DRG THE DAY THURSDAY, WINDS SHIFT ARND TO A SWRLY DIRECTION BRINGING
LINGERING LK EFFECT SHOWERS OUT OF THE CWA. NEXT IN A SERIES OF
CDFNTS WL APPCH THE AREA THUR NGT INTO FRI MRNG. EXTENSIVE CLD CVR
WL BE PRESENT AHD OF THE FNT...KEEPING OVRNT MINS ARND 40F. CHC POPS
WL MV INTO THE NRN ZONES BY 12Z FRI...CONTG IN NY STATE THRU 18Z BFR
FADING OUT AS UL WV WEAKENS AND MOST OF THE LIFT GOES OFF TO THE
NORTH IN CANADA AND SHEARS ITSELF OUT. SKIES WL CLR DRG THE AFTN AS
SFC HIPRES BUILDS OVR TOP OF THE AREA ON FRIDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
PROGRESSIVE PTRN OVER THE MEDIUM RNG WITH S/WV`S PASSING EVERY
COUPLE OF DAYS W/ASSCD FNTL SYSTEMS. HIGH PRESSURE XPCTD TO BE
CNTRD OVER THE FCST AREA BY LATER FRI NGT...AND CLEARING SKIES
MAY ALLOW FOR AN AREA-WIDE FROST/FREEZE AND AN OFFICIAL END TO THE
GROWING SEASON. THE HIGH WILL SLIDE EWD TO THE CST BY SUNDAY
EVNG...WITH A VERY NICE DAY ANTICIPATED ON SAT. THE NXT S/WVS
APRCH FROM THE GTLAKES/OH VLY ON SUNDAY/SUN NGT WITH MORE -SHRA.
MON AND TUE LOOK DRY AT THIS TIME ALTHO A STRAY -SHRA CAN`T BE
RULED OUT SO WE RETAINED THE SLGT CHC POPS FOR THIS TIME. HPC
GUIDANCE LOOKED GOOD AND USED WITH ONLY MINOR TWEEKS.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
A SOLID MARINE LAYER CONTINUES TO OVERSPREAD THE REGION EARLY THIS
EVENING WITH OVERCAST SKIES PREVAILING OVER MOST TERMINALS. MAIN
QUESTION AS WE PROGRESS INTO THE OVERNIGHT PERIOD IS JUST HOW LOW
CIGS WILL GO AFTER 06Z. NEAR SFC WINDS SHOULD REMAIN FROM THE
SOUTHEAST OVERNIGHT WHICH WILL LIKELY ALLOW BGM TO FALL BELOW IFR
THRESHOLDS THE SOONEST. AT AVP...SOUTHWEST WINDS TRADITIONALLY RESULT
IN LOW-END MVFR CIGS AND HAVE MAINTAINED THAT SUGGESTION WITH THE
00Z ISSUANCE. THE POTENTIAL FLY IN THE OINTMENT FOR BOTH BGM AND
AVP HINGES ON POSSIBLE -DZ ACTIVITY WHICH MAY RESULT IN LOWER CIGS
THAN CURRENTLY FCST. MEANWHILE AT BOTH ITH AND RME...SOUTHEAST
WINDS TRADITIONALLY FAVOR LITTLE IFR AT BOTH SITES AND HAVE
DECIDED TO MAINTAIN MVFR MENTION AT BOTH SITES. MARINE DECK SHOULD
CONTINUE TO OVERSPREAD BOTH SYR AND ELM OVERNIGHT HOWEVER WE
CURRENTLY ONLY EXPECT MVFR CONDITIONS FOR THE TIME BEING.
WINDS WILL INCREASE OUT OF THE SOUTHWEST AFTER 12Z AS THE PRESSURE
GRADIENT INCREASES AHEAD OF AN APPROACHING COLD FRONT. FRONT
EXPECTED TO PASS AFTER 18Z WHICH WILL LEAD TO REDEVELOPING SHWRS
DURING THE MID/LATE AFTERNOON HRS.
OUTLOOK...
WED NGT...VFR...XCPT PSBL MVFR AT RME/SYR DUE TO LAKE CLDS/SHRA.
THU...VFR...BUT MVFR PSBL THU MRNG AT RME.
THU NGT...CONDITIONS DETERIORATING TO MVFR IN SHRA WITH CDFNT.
FRI...MVFR POSSIBLE EARLY MAINLY SRN NY AND NE PA...OTRW IMPRVMNT
TO VFR.
SAT...VFR.
SUN...MVFR IN SHRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...PVN
LONG TERM...
AVIATION...CMG
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
154 AM EDT WED OCT 10 2012
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL SHIFT INTO EASTERN CANADA
TONIGHT...AS A SURFACE COLD FRONT APPROACHES THE SAINT LAWRENCE
VALLEY BY WEDNESDAY. THIS COLD FRONT WILL PRODUCE A BRIEF PERIOD OF
SHOWERS FROM WEST TO EAST ACROSS THE AREA ON WEDNESDAY INTO
WEDNESDAY EVENING...ALONG WITH BREEZY SOUTHERLY WINDS. THESE WINDS
WILL SHIFT TO THE WEST AND COOLER TEMPERATURES WILL ARRIVE BY
THURSDAY. A SECONDARY COLD FRONT WILL PRODUCE MORE LIGHT SHOWERS ON
FRIDAY...WITH SOME HIGH ELEVATION SNOW SHOWERS POSSIBLE...WITH EVEN
COOLER TEMPERATURES AND WIDESPREAD FROST EXPECTED ON SATURDAY
MORNING.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1031 PM EDT TUESDAY...GOING FORECAST REMAINS IN GOOD SHAPE
WITH GENERALLY QUIET WX THROUGH THE OVERNIGHT. CONTINUE TO
MONITOR NWD MOVEMENT AND EVOLUTION OF PATCHY STRATUS LAYER ACROSS
THE NORTH COUNTRY AT 02Z AND HAVE ADJUSTED CLOUD COVER
ACCORDINGLY. GENERALLY OVC FROM MPV SOUTHWARD...BUT MOSTLY CLEAR
SKIES PREVAIL FROM THE CHAMPLAIN VALLEY WWD ACROSS THE NRN
ADIRONDACKS AND IS CAUSING LARGE TEMPERATURE VARIATIONS. CLEAR
SKIES AT KSLK HAS ALLOWED THE TEMPERATURE TO FALL TO 34F AT
02Z...MEANWHILE REMAINS 51F AT BTV WITH SE WINDS AND 51F AT VSF
WITH LOW OVERCAST IN PLACE THERE. OVERALL TREND SHOULD BE TOWARD
INCREASING CLOUDS...BUT OCCASIONAL BINOVC WILL CONTINUE. LOW TEMPS
GENERALLY IN THE 40S OVERNIGHT...EXCEPT LOCALLY NEAR FREEZING AT
KSLK. LIGHT SOUTH TO SE WINDS WILL ALSO HELP KEEP THE TEMPERATURES
IN THE 40S IN THE CHAMPLAIN VALLEY OVERNIGHT. SOME WEAK
REFLECTIVITY RETURNS MVG NWD FROM NERN PA INTO S-CENTRAL NY PER
MOSAIC COMPOSITE REFLECTIVITY...AND INCLUDED A SLIGHT CHANCE OF A
SHOWER OR SPRINKLE ACROSS THE NRN ADIRONDACKS TOWARD DAYBREAK.
PREVIOUS DISCUSSION...FCST CHALLENGE WL BE TIMING OF FROPA AND
ASSOCIATED POPS/QPF ON WEDS AFTN/EVENING. WATER VAPOR SHOWS SMALL
ENVELOPE OF DRY AIR ACRS OUR CWA THIS AFTN...ASSOCIATED WITH
SUBSIDENCE FROM SYSTEM WELL OFF THE COAST..WITH NEXT RIBBON OF
ENHANCED MOISTURE/VORT DIVING TWD THE CENTRAL GREAT LAKES ATTM.
WEAK PRE-FRNTAL VORT AND RIBBON OF MOISTURE WL LIFT ACRS OUR
WESTERN/CENTRAL CWA THIS EVENING...WITH LLVL ATLANTIC MOISTURE
ADVECTING AROUND HIGH PRES IMPACTING OUR CENTRAL/EASTERN CWA.
PATCHY DRIZZLE/VERY LIGHT RAIN WL BE POSSIBLE ACRS OUR EASTERN ZNS
MTNS TONIGHT. CLOUD GRIDS AND ASSOCIATED TEMPS WL BE TRICKY
TONIGHT. RUC13 925MB TO 700MB RH PROGS SHOW PLENTY OF MOISTURE
ALONG AND EAST OF THE GREEN MTNS THRU THIS EVENING...THEREFORE WL
MENTION MOSTLY CLOUDY SKIES AND KEEP TEMPS IN THE 40S...MAYBE A
FEW 30S NORTHERN ZNS. ELSEWHERE...SKIES SHOULD BE PC WITH TEMPS IN
U30S DACKS TO 40S CPV/SLV.
FOR WEDNESDAY...POTENT S/W ENERGY AND ASSOCIATED ENHANCED RIBBON OF
MID LVL RH WL ENTER THE SLV AROUND 16Z...BE ACRS THE DACKS BTWN
18Z-20Z...CPV AROUND 21Z...AND THRU VT BY 02Z THURS. NAM12 SHOWS
GOOD 925MB FGEN FORCING...GOOD 850 TO 700MB RH/OMEGA FIELDS...AND
PWS VALUES NEAR 0.75"...WHICH WL RESULT IN A 1 TO 3 HR WINDOW OF
SHOWERS. FAST MOVEMENT OF SYSTEM AND LIMITED DEEP LAYER MOISTURE
ADVECTION WL KEEP QPF AMOUNT GENERALLY <0.25"...WITH HIGHEST VALUES
ACRS THE MTNS. HIGH RESOLUTION MODELS SHOW SOME CHANNELING EFFECTS
ACRS THE SLV/CPV WITH LOCALIZED WIND GUSTS BTWN 30 AND 35 MPH
POSSIBLE. PROGGED 85H SOUTHWEST FLW OF 35 TO 40 KNTS AHEAD OF SYSTEM
WL LIMIT QPF/POP CHCS ACRS THE CPV ON WEDS. WL TREND TEMPS SEVERAL
DEGREES ABOVE GUIDANCE GIVEN SOUTHERLY FLW AND PROGGED 925MB TEMPS
NEAR 11C. THINKING M50S MTNS TO M60S VALLEYS...WITH WARMEST READINGS
AT VSF.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
AS OF 350 PM EDT TUESDAY...MID/UPPER LVL TROF DEEPENS BEHIND SFC
COLD FRNT...BUT STRONG SFC PRES GRADIENT BTWN HIGH PRES ACRS THE
OHIO VALLEY AND DEPARTING LOW PRES WL KEEP TEMPS FROM DROPPING TOO
FAR. GIVEN...A WEST TO NORTHWEST FLW BTWN 925MB AND
850MB...THINKING BEST LAKE EFFECT MOISTURE WL STAY SOUTH OF OUR
CWA ON WEDS NIGHT. THE COMBINATION OF UPSLOPE NW FLW AND LEFTOVER
850 TO 700MB RH...MAY PRODUCE A FEW MTN FLURRIES/SNOW SHOWERS ON
WEDS NIGHT...AS 85H TEMPS COOL BLW 0C. GFS SOUNDINGS AT JAY PEAK
SHOW THIS POTENTIAL...WITH A DUSTING OF SNOW POSSIBLE BY THURS
MORNING FROM SUGARBUSH TO MOUNT MANSFIELD TO JAY PEAK. SOUNDINGS
SHOW WELL MIXED BL WITH CAA ACRS OUR CWA...WL MENTION LOWS FROM
THE U20S MTNS TO U30S VALLEYS AND L40S NEAR LAKE CHAMPLAIN.
ON THURSDAY...SFC RIDGE AXIS MOVES ACRS OUR CWA BY 18Z...WITH RETURN
SOUTHWEST FLW DEVELOPING BY 00Z FRIDAY. BOTH GFS/NAM SHOW ENHANCED
850 TO 500MB RH IMPACTING THE SLV BY 18Z THURS AND SPREADING TWD THE
CPV BY 00Z FRIDAY...ASSOCIATED WITH LOW TO MID WAA AHEAD OF NEXT
SYSTEM. THIS FAST MOVING CLIPPER LIKE SYSTEM WL PUSH ACRS OUR CWA
THUR NIGHT INTO FRIDAY MORNING. THIS NORTHERN STREAM SYSTEM WL HAVE
LIMITED MOISTURE...BUT GIVEN STRONG DYNAMICS AND GOOD SFC
CONVERGENCE...EXPECT ANOTHER BRIEF PERIOD OF SHOWERS OVERNIGHT INTO
FRIDAY MORNING..WITH HIGHEST POPS/QPF CONCENTRATED ACRS THE MTNS.
MUCH COOLER TEMPS ARRIVE ON FRIDAY INTO SATURDAY BEHIND THIS SYSTEM.
FOR THURSDAY...PROGGED 85H TEMPS WARM TO NEAR 0C...BUT INCREASE
CLOUDS MAY LIMIT SFC HEATING/MIXING...THINKING U40S NEK TO NEAR 60F
CPV/SLV. THE COMBINATION OF SOUTHERLY SFC WINDS FROM APPROACHING
BOUNDARY...INCREASING CLOUDS/PRECIP...AND WARMING LLVL THERMAL
PROFILES ON THURS NIGHT...WL MENTION LOWS ABOVE GUIDANCE AND MAINLY
IN THE 40S. HOWEVER...TWD FRIDAY MORNING LLVL CAA DEVELOPS AND
THERMAL PROFILES ABOVE 2000 FT WL BECM COLD ENOUGH TO SUPPORT SOME
SNOW. HAVE MENTION A MIX OF RAIN/SNOW WITH SOME LIGHT ACCUMULATION
POSSIBLE ABOVE 3000 FT AROUND 12Z FRIDAY.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 326 PM EDT TUESDAY...UPPER TROUGH SWINGS THRU THE CWA DURING
THE DAY ON FRIDAY. MDLS CONTINUE TO SHOW SFC RIDGE BUILDING OVER
THE NORTH COUNTRY FRI NGT INTO SATURDAY. SATURDAY NIGHT HAS WARM
FRNTL BOUNDARY SWING THRU THE WESTERN PORTIONS OF THE
CWA...OVERSPREADING THE ENTIRE CWA SLOWLY ON SUNDAY. SFC LOW
ASSOCIATED WITH FRNT LIFTS NORTH OF CWA TRAVELING EAST THRU QUEBEC
INTO MONDAY. TIMING ISSUES WITH EXITING SYSTEM ON MONDAY INTO
TUESDAY AS LATEST ECMWF DIGS UPPER TROUGH FURTHER SOUTH. THIS WILL
POTENTIALLY KEEP PRECIP LONGER OVER THE AREA...WHILE THE LATEST
GFS BRINGS DRIER AIR WITH RIDGE FROM GREAT LKS REGION.
IMPACTS FOR THE NORTH COUNTRY...
FRIDAY...MOST OF THE REGION WILL SEE LGT -RW...EMPHASIS WILL BE OVER
HIR TRRN AS PRECIP TAPERS OFF WITH WNW FLOW OVER THE AREA. SOME --SW
POSSIBLE AT 1500-2000` OR HIR FOR A FEW HRS IN THE MORNING...BECM
ALL -RW BFR ENDING.
FRIDAY NIGHT THRU SATURDAY...CWA WILL RADIATE OUT UNDER CLR SKIES
FRI NGT ALLOWING FOR TEMPS TO DROP INTO THE TEENS AND 20S CWA-WIDE.
COLDER TEMPS IN THE HILLS OF DACKS NE VT. RIDGE SHIFTS EAST DURING
THE DAY SATURDAY ALLOWING FOR WARM UP WITH HGHS INTO THE MID50S AS
SSW FLOW INCR AHEAD OF APPROACHING WARM FRNT.
SATURDAY NIGHT THRU TUESDAY...LGT PRECIP/CLDS INCR OVER N NY SAT NGT
OVERSPREADING CWA BY SUNDAY MORNING. POSITIONING OF WARM FRNT ON
GFS/ECMWF EXTENT OF ANY -SW THAT DEMELOP OVE RHIR TRRN BFR GOING TO
ALL -RW. SYSTEM SLIDES SLOWLY EAST THRU SUN/SUN NGT AS PARENT LOW
SHIFTS INTO SOUTHERN QUEBEC. WILL KEEP CHANCE FOR -RW OVER AREA
THRU PERIOD. LATE SUNDAY NIGHT INTO MONDAY W/ FRNT LIFTING N OF
CWA...PRECIP WILL SCT OUT SOME AS DRIER AIR WORKS INTO AREA. WILL BE
KEEPING CHANCE POPS FOR -RW TRANSITIONING TO LGT -SW OVER HIR AS CD
AIR FILTERS INTO AREA UNDER NW. FOR NOW WITH MDL UNCERTAINTY HAVE
KEPT SL CHANCE FOR TUESDAY FOR SHOWERS.
TEMPS FOR THE EXTENDED BLW NORMAL BY A FEW DEGREES WITH RIDGE
OVERHD...AND INCR TO AT OR ABV NORMAL CONDITIONS DUE TO WARMER
AIRMASS WORKING INTO AREA W/ FRNT.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
THROUGH 06Z THURSDAY...LOW LEVEL MOISTURE...PRODUCING A STRATUS
DECK WILL CONTINUE TO AFFECT MOST OF THE NORTH COUNTRY. THE
NORTHERN EXTENT OF THIS DECK WILL RESULT IN VARYING FLIGHT
CONDITIONS OVER THE AREA. KMPV AND KSLK EXPECTING TO EXPERIENCE
THE WORST...WITH LIFR AND VLIFR CIGS THROUGH SUNRISE. KRUT EXPECT
LOW LEVEL MOISTURE TO MOVE OVER THE TAF SITE...BUT DOWNSLOPING
WINDS WILL PROVIDE MOSTLY VFR CIGS...HAVE INCLUDED TEMPO AS
POSSIBILITY STILL EXISTS FOR MVFR CIGS. OTHERWISE VFR CONDITIONS
EXPECTED AT KBTV...KPBG...KMSS THROUGH THE AFTERNOON.
A COLD FRONT WILL PUSH ACROSS THE REGION DURING THE AFTERNOON AND
EVENING WITH GUSTY SOUTH TO SOUTHWEST WINDS OUT AHEAD OF IT.
GUSTS ARE EXPECTED TO REACH 20-25 KNOTS AT TIMES AT
BTV/PBG/MSS/SLK. BAND OF RAIN SHOWERS ASSOCIATED WITH THE FRONT
WILL PUSH EASTWARD LOWERING CIGS TO MVFR AT KMPV AND KSLK.
SHOWERS WILL ENTER THE ST LAWRENCE VALLEY AROUND 17Z AND PUSH
EAST TO KSLK AT 18Z...REACHING THE CHAMPLAIN VALLEY AND VT AROUND
20-21Z. VISIBILITIES WILL LIKELY LOWER TO MVFR/IFR AT
TIMES...ALTHOUGH TIMING OF HEAVIEST RAIN UNCERTAIN AT THIS TIME.
EXPECT PRECIP TO END WEST TO EAST WEDNESDAY EVENING. CIGS WILL
IMPROVE TO VFR RAPIDLY AS THE BACK EDGE OF THE CLOUD SHIELD MOVES
ACROSS THE NORTH COUNTRY OVERNIGHT. AT THAT TIME...WINDS WILL
SHIFT SW TO W...DECREASING IN SPEED AND GUSTS TO LESS THAN 12
KTS.
OUTLOOK 06Z THURSDAY THROUGH SUNDAY...
06Z THURSDAY THROUGH 12Z THURSDAY...PRIMARILY VFR EXPECTED...WITH
PERIODS OF MVFR FG/BR POSSIBLE...ESPECIALLY SLK/MPV.
12Z THURSDAY THROUGH 00Z FRIDAY...MAINLY VFR AS WEAK RIDGE OF
HIGH PRESSURE WILL BE OVER THE REGION.
00Z FRIDAY THROUGH 18Z FRIDAY...MAINLY VFR WITH PERIOD OF MVFR
POSSIBLE IN RAIN SHOWERS WITH COLD FRONT.
18Z FRIDAY THROUGH 06Z SUNDAY...PREDOMINANTLY VFR AS A RIDGE OF
HIGH PRESSURE BUILDS INTO THE REGION.
06Z SUNDAY ONWARD...VFR TRENDING MVFR IN PERIODS OF RAIN SHOWERS
WITH LOW PRESSURE SYSTEM.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...TABER
NEAR TERM...BANACOS/TABER
SHORT TERM...TABER
LONG TERM...JN
AVIATION...KGM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
715 AM EDT WED OCT 10 2012
.SYNOPSIS...
DRIER AIR WILL SPREAD INTO THE AREA FROM THE WEST TODAY...LEADING TO
ABUNDANT SUNSHINE AND MUCH WARMER TEMPERATURES. A DRY COLD FRONT
WILL THEN SWEEP THROUGH THE AREA LATE THIS EVENING AND BRING
TEMPERATURES BACK DOWN BELOW SEASONAL NORMALS FOR THURSDAY.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 245 AM WEDNESDAY...
STRATUS REMAINS LOCKED IN BELOW THE INVERSION AT 850MB THIS
MORNING...ALTHOUGH THERE IS A WEST-SOUTHWESTERLY PUSH OF DRIER LOW
LEVEL AIR BEGINNING TO WORK ITS WAY UP FROM SC ND SOUTHWESTERN
NC WHERE STRATUS IS BEGINNING TO CLEAR. IMMEDIATELY BEHIND THE
CLEARING LINE...WHICH CURRENTLY STRETCHES FROM KEHO TO KFLO...LIGHT
SURFACE WINDS AND COOLING MAY PROMOTE SOME LOCALIZED FOG AND LOW
CLOUDS JUST PRIOR TO SUNRISE. MEANWHILE...DEEP WESTERLY FLOW WILL
BECOME ESTABLISHED OVER AREA AS A LOW PRESSURE SYSTEM CROSSES THE
NORTHERN GREAT LAKES REGION AND THE UPPER TROUGH AXIS SHIFTS EAST
THE OH VALLEY REGION. RAP SOUNDINGS SHOW A RELATIVELY RAPID
CLEARING OF LOW CLOUDS ACROSS THE PIEDMONT AND COASTAL PLAIN BY
AROUND 14-16Z. THUS... MUCH OF THE DAY WILL FEATURE MOSTLY SUNNY
SKIES. A PLUME OF PREFRONTAL MOISTURE AHEAD OF A COLD FRONT
CURRENTLY CROSSING IL/MO IS FORECAST UNDERGO QUITE A BIT OF DRYING
AS IT ENCOUNTERS THE MOUNTAINS THIS AFTERNOON. HOWEVER...
CROSS-SECTIONS SUGGEST THERE MAY BE ENOUGH MOISTURE FOR A SCATTERED
CUMULUS FIELD TO DEVELOP IN THE LEE TROUGH OVER THE WESTERN PIEDMONT
THIS AFTERNOON. OTHERWISE...UNDER FULL SUN AND A WEAK WESTERLY
DOWNSLOPE WIND COMPONENT...DRY ADIABATIC MIXING TO NEAR 850MB YIELDS
HIGHS IN THE LOW TO MID 70S FROM WEST TO EAST.
TONIGHT...
THE AFOREMENTIONED DRY COLD FRONT WILL CROSS THE AREA BETWEEN 00Z
AND 06Z THIS EVENING...WITH ONLY A FEW CLOUDS ACCOMPANYING THE
FROPA. POST-FRONTAL COLD ADVECTION WILL DRIVE LOWS INTO THE LOW TO
MID 40S...THOUGH THE MAV MOS SHOWS UPPER 30S ACROSS THE NORTHERN
PIEDMONT. HOWEVER...A LIGHT WIND AND DRYING THROUGH 12Z SHOULD
PRECLUDE ANY FROST.
THURSDAY...
HIGH PRESSURE WILL SETTLE ACROSS WV AND WEAKEN OVER VA/NC THURSDAY
AFTERNOON...WHILE ANOTHER WEAK COLD FRONT MOVES INTO THE OH VALLEY.
1000-850MB THICKNESSES ARE FORECAST TO BE AROUND 1335M AT 12Z
THURSDAY...WHICH YIELDS MOST MID AND UPPER 60S BASED ON CLIMATOLOGY.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
AS OF 240 AM WEDNESDAY...
FOR THURSDAY NIGHT: FAIR AND CALM WITH A SURFACE HIGH PRESSURE RIDGE
SITTING OVERHEAD. A MID LEVEL PERTURBATION MOVING THROUGH THE
LONGWAVE TROUGH BASE WILL MOVE INTO KY/TN OVERNIGHT... LIKELY
ACCOMPANIED BY A MATURE MCS TRACKING ALONG THE LOW LEVEL FRONTAL
ZONE. THE ASSOCIATED UPPER LEVEL ACCELERATION FROM THE OH VALLEY
TOWARD VA/NC AND THE RESULTANT AGEOSTROPHIC RESPONSE WILL BRING
ABOUT INCREASING UPPER DIVERGENCE IN THE JET`S LEFT EXIT REGION OVER
NC... WHICH SHOULD SUPPORT A MAINTENANCE OF HIGH CLOUDS BLOWN OFF
FROM THE UPSTREAM CONVECTION SPREADING INTO NC OVERNIGHT. THE NEARLY
CALM SURFACE AIR AND GOOD RADIATIONAL COOLING WILL BE JUST SLIGHTLY
OFFSET BY THE VEIL OF HIGH CLOUDS OVERNIGHT... AND EXPECT LOWS ON
THE LOW END OF STATISTICAL GUIDANCE... 40-45... BUT WITH THE MILDER
TEMPS IN THE WEST WHERE THE HIGH CLOUDS WILL BE FIRST TO ARRIVE.
WHILE A FEW UPPER 30S ARE CERTAINLY POSSIBLE PRIMARILY IN THE LOW
SHELTERED AREAS OF THE COASTAL PLAIN AND NE PIEDMONT... A WIDESPREAD
FROST THREAT IS NOT EXPECTED.
FOR FRIDAY/FRIDAY NIGHT: THE SURFACE HIGH CENTERED OVER NC LATE
THURSDAY NIGHT WILL CONTINUE SINKING TO THE SW FRIDAY. MEANWHILE...
THE SURFACE FRONT EXPECTED TO STRETCH ACROSS THE OH VALLEY TO NJ
FRIDAY MORNING WILL SLOWLY SINK TO THE SE AND S... DROPPING THROUGH
NC FRIDAY NIGHT... PROPELLED BY THE COOL DENSE POST-FRONT AIR MASS
MOVING FROM THE UPPER MIDWEST TO PA... AND BY THE STRONG MID LEVEL
SHORTWAVE TROUGH CROSSING QUEBEC AND THE CANADIAN MARITIMES AND
NORTHEAST STATES. THE FRONT SHOULD COME THROUGH DRY GIVEN THE LACK
OF DEEP MOISTURE AND LIFT AND THE PRECEDING DOWNSLOPE NORTHWESTERLY
925 MB FLOW. THE KY/TN CONVECTIVE COMPLEX IS LIKELY TO DISSIPATE
CROSSING THE SRN APPALACHIANS EARLY FRIDAY AS THE MID LEVEL
PERTURBATION DAMPENS OUT AND SKIRTS TO OUR SW... BUT WE SHOULD STILL
SEE A PERIOD OF THICKER CLOUDS PARTICULARLY OVER THE WRN AND SRN CWA
FRIDAY AS THE REMNANT CLOUDS PASS OVER NC... THUS EXPECT PARTLY
SUNNY TO MOSTLY CLOUDY SKIES FOR A PORTION OF THE DAY AS MODELS
DEPICT INCREASING LOW LEVEL THETA-E BENEATH THE WARM/STABLE LAYER
ALOFT (AROUND 700 MB). HAVE TRIMMED A COUPLE OF DEGREES OFF FORECAST
HIGHS... TO 71-76. AS THE FRONT DROPS THROUGH THE AREA IN THE
EVENING... SURFACE WINDS WILL VEER AROUND TO NORTHEASTERLY AND COULD
BE RATHER GUSTY IMMEDIATELY BEHIND THE FRONT. THE STABILIZATION IN
THE LOWEST 200 MB (AROUND 2 KM) CAPPED BY MID LEVEL
SUBSIDENCE/WARMING AND THE HIGH THETA-E TRAPPED IN THE UPPER
PORTIONS OF THIS STABLE LAYER SHOULD RESULT IN SCATTERED TO BROKEN
CLOUDS FOR MUCH OF THE NIGHT. LOWS FROM 41 NORTH TO 47 SOUTH WITH
STRONG LOW LEVEL COLD AIR ADVECTION OVERNIGHT. -GIH
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 250 AM WEDNESDAY...
FOR SATURDAY/SATURDAY NIGHT: DRY AND COOL. NORTHWESTERLY MID LEVEL
FLOW DIMINISHES AND BACKS TO WSW AS RIDGING BUILDS OVER THE
SOUTHEAST... IN RESPONSE TO THE CLOSED LOW NOW OFF THE CENTRAL CA
COAST EJECTING NORTHEASTWARD AS AN OPEN WAVE THROUGH THE PLAINS. AT
THE SURFACE... THE CHILLY SURFACE HIGH TO OUR NORTH CONTINUES TO
NOSE INTO NC AS IT PROGRESSES STEADILY EASTWARD OFF THE MIDATLANTIC
COAST. THE COLUMN REMAINS DRY AND SUBSIDING... AND EXPECT ONLY A FEW
FLAT STRATOCUMULUS CLOUDS. THE SHALLOW MIXED LAYER SUPPORTS
BELOW-NORMAL HIGHS OF 65-71. AS THE SURFACE HIGH CENTER SHIFTS
FURTHER OUT OVER THE ATLANTIC WITH THE RIDGE STILL EXTENDING BACK
INTO NC... THE RETURN FLOW AND INCREASING FETCH OF LOW LEVEL
ATLANTIC MOISTURE COMBINED WITH THE NIGHTTIME COOLING/STABILIZATION
SUPPORTS POCKETS OF FOG AND STRATUS DEVELOPMENT SATURDAY NIGHT. LOWS
48-52.
FOR SUNDAY THROUGH TUESDAY: THE AFOREMENTIONED OPEN WAVE DAMPENS A
BIT MORE AS IT MOVES EAST OVER NRN SECTIONS OF THE GREAT LAKES
SUNDAY... ALTHOUGH AN INJECTION OF POLAR STREAM ENERGY FROM
SASKATCHEWAN IS APT TO RESTRENGTHEN THE SHORTWAVE TROUGH SOMEWHERE
OVER THE ST LAWRENCE VALLEY BY LATE MONDAY. MODELS DISAGREE ON
EXACTLY WHERE THE SHORTWAVE TROUGH WILL MOVE AND HOW DEEP IT WILL BE
(THE ECMWF IS SLOWER/DEEPER THAN THE LAST TWO RUNS OF THE GFS).
WE`LL FIRST SEE THE LEE TROUGH DEEPEN OVER CENTRAL NC SUNDAY WITH
WARMING THICKNESSES... THEN A COLD FRONT WILL LIKELY APPROACH NC
FROM THE NNW... EARLY MONDAY ON THE GFS AND NOT UNTIL EARLY TUESDAY
ON THE ECMWF. GIVEN THIS STARK DIFFERENCE IN SOLUTIONS WITH REDUCED
CONFIDENCE GIVEN THE FAST MID LEVEL FLOW TO OUR NORTH... WILL MAKE
FEW CHANGES... HOLDING ONTO ABOVE-NORMAL TEMPS. WILL INCLUDE A
MENTION OF AN ISOLATED SHOWER CHANCE ON MONDAY/MONDAY NIGHT WITH
FRONTAL PASSAGE AS LOW LEVEL MOISTURE WILL HAVE INCREASED
SUFFICIENTLY DUE TO THE ATLANTIC INFLOW. WHICHEVER MODEL SOLUTION
ENDS UP MORE CORRECT (IF EITHER)... THE TRUE POLAR AIR WILL BE
LOCKED UP IN THE FAR NRN TIER AND CANADA... THUS NO WIDE SWINGS IN
TEMPS ARE EXPECTED EITHER WAY... AND THE LIMITED GULF MOISTURE WILL
FAVOR LOW PRECIP CHANCES. -GIH
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 715 AM WEDNESDAY...
LOW STRATUS IS CLEARING RAPIDLY FROM SOUTHWEST TO NORTHEAST THIS
MORNING. THE BACK EDGE OF THE CLEARING HAS PASSED BY
KFAY/KINT/KGSO...THOUGH A FEW PATCHES OF 2500 FT STRATUS MAY LINGER
THROUGH 14Z. CLEARING WILL TAKE PLACE AT KRDU BETWEEN 12Z-13Z AND
AT KRWI BY 15Z. STEADY 8-12KT WESTERLY WIND WILL DEVELOP THIS
AFTERNOON...BACKING SLIGHTLY TO SOUTHWESTERLY THIS EVENING AS A DRY
COLD FRONT MOVES INTO THE AREA FROM THE NORTHWEST AFTER 00Z. FROPA
SHOULD OCCUR FROM WEST TO EAST BETWEEN 00Z-04Z...WITH ONLY A FEW
HIGH BASED CLOUDS ACCOMPANYING THE FRONT.
OUTLOOK...
VFR CONDITIONS ARE EXPECTED THROUGH THIS WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BLS
NEAR TERM...BLS
SHORT TERM...HARTFIELD
LONG TERM...HARTFIELD
AVIATION...BLS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
303 AM EDT WED OCT 10 2012
.SYNOPSIS...
DRIER AIR WILL SPREAD INTO THE AREA FROM THE WEST TODAY...LEADING TO
ABUNDANT SUNSHINE AND MUCH WARMER TEMPERATURES. A DRY COLD FRONT
WILL THEN SWEEP THROUGH THE AREA LATE THIS EVENING AND BRING
TEMPERATURES BACK DOWN BELOW SEASONAL NORMALS FOR THURSDAY.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 245 AM WEDNESDAY...
STRATUS REMAINS LOCKED IN BELOW THE INVERSION AT 850MB THIS
MORNING...ALTHOUGH THERE IS A WEST-SOUTHWESTERLY PUSH OF DRIER LOW
LEVEL AIR BEGINNING TO WORK ITS WAY UP FROM SC ND SOUTHWESTERN
NC WHERE STRATUS IS BEGINNING TO CLEAR. IMMEDIATELY BEHIND THE
CLEARING LINE...WHICH CURRENTLY STRETCHES FROM KEHO TO KFLO...LIGHT
SURFACE WINDS AND COOLING MAY PROMOTE SOME LOCALIZED FOG AND LOW
CLOUDS JUST PRIOR TO SUNRISE. MEANWHILE...DEEP WESTERLY FLOW WILL
BECOME ESTABLISHED OVER AREA AS A LOW PRESSURE SYSTEM CROSSES THE
NORTHERN GREAT LAKES REGION AND THE UPPER TROUGH AXIS SHIFTS EAST
THE OH VALLEY REGION. RAP SOUNDINGS SHOW A RELATIVELY RAPID
CLEARING OF LOW CLOUDS ACROSS THE PIEDMONT AND COASTAL PLAIN BY
AROUND 14-16Z. THUS... MUCH OF THE DAY WILL FEATURE MOSTLY SUNNY
SKIES. A PLUME OF PREFRONTAL MOISTURE AHEAD OF A COLD FRONT
CURRENTLY CROSSING IL/MO IS FORECAST UNDERGO QUITE A BIT OF DRYING
AS IT ENCOUNTERS THE MOUNTAINS THIS AFTERNOON. HOWEVER...
CROSS-SECTIONS SUGGEST THERE MAY BE ENOUGH MOISTURE FOR A SCATTERED
CUMULUS FIELD TO DEVELOP IN THE LEE TROUGH OVER THE WESTERN PIEDMONT
THIS AFTERNOON. OTHERWISE...UNDER FULL SUN AND A WEAK WESTERLY
DOWNSLOPE WIND COMPONENT...DRY ADIABATIC MIXING TO NEAR 850MB YIELDS
HIGHS IN THE LOW TO MID 70S FROM WEST TO EAST.
TONIGHT...
THE AFOREMENTIONED DRY COLD FRONT WILL CROSS THE AREA BETWEEN 00Z
AND 06Z THIS EVENING...WITH ONLY A FEW CLOUDS ACCOMPANYING THE
FROPA. POST-FRONTAL COLD ADVECTION WILL DRIVE LOWS INTO THE LOW TO
MID 40S...THOUGH THE MAV MOS SHOWS UPPER 30S ACROSS THE NORTHERN
PIEDMONT. HOWEVER...A LIGHT WIND AND DRYING THROUGH 12Z SHOULD
PRECLUDE ANY FROST.
THURSDAY...
HIGH PRESSURE WILL SETTLE ACROSS WV AND WEAKEN OVER VA/NC THURSDAY
AFTERNOON...WHILE ANOTHER WEAK COLD FRONT MOVES INTO THE OH VALLEY.
1000-850MB THICKNESSES ARE FORECAST TO BE AROUND 1335M AT 12Z
THURSDAY...WHICH YIELDS MOST MID AND UPPER 60S BASED ON CLIMATOLOGY.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
AS OF 240 AM WEDNESDAY...
FOR THURSDAY NIGHT: FAIR AND CALM WITH A SURFACE HIGH PRESSURE RIDGE
SITTING OVERHEAD. A MID LEVEL PERTURBATION MOVING THROUGH THE
LONGWAVE TROUGH BASE WILL MOVE INTO KY/TN OVERNIGHT... LIKELY
ACCOMPANIED BY A MATURE MCS TRACKING ALONG THE LOW LEVEL FRONTAL
ZONE. THE ASSOCIATED UPPER LEVEL ACCELERATION FROM THE OH VALLEY
TOWARD VA/NC AND THE RESULTANT AGEOSTROPHIC RESPONSE WILL BRING
ABOUT INCREASING UPPER DIVERGENCE IN THE JET`S LEFT EXIT REGION OVER
NC... WHICH SHOULD SUPPORT A MAINTENANCE OF HIGH CLOUDS BLOWN OFF
FROM THE UPSTREAM CONVECTION SPREADING INTO NC OVERNIGHT. THE NEARLY
CALM SURFACE AIR AND GOOD RADIATIONAL COOLING WILL BE JUST SLIGHTLY
OFFSET BY THE VEIL OF HIGH CLOUDS OVERNIGHT... AND EXPECT LOWS ON
THE LOW END OF STATISTICAL GUIDANCE... 40-45... BUT WITH THE MILDER
TEMPS IN THE WEST WHERE THE HIGH CLOUDS WILL BE FIRST TO ARRIVE.
WHILE A FEW UPPER 30S ARE CERTAINLY POSSIBLE PRIMARILY IN THE LOW
SHELTERED AREAS OF THE COASTAL PLAIN AND NE PIEDMONT... A WIDESPREAD
FROST THREAT IS NOT EXPECTED.
FOR FRIDAY/FRIDAY NIGHT: THE SURFACE HIGH CENTERED OVER NC LATE
THURSDAY NIGHT WILL CONTINUE SINKING TO THE SW FRIDAY. MEANWHILE...
THE SURFACE FRONT EXPECTED TO STRETCH ACROSS THE OH VALLEY TO NJ
FRIDAY MORNING WILL SLOWLY SINK TO THE SE AND S... DROPPING THROUGH
NC FRIDAY NIGHT... PROPELLED BY THE COOL DENSE POST-FRONT AIR MASS
MOVING FROM THE UPPER MIDWEST TO PA... AND BY THE STRONG MID LEVEL
SHORTWAVE TROUGH CROSSING QUEBEC AND THE CANADIAN MARITIMES AND
NORTHEAST STATES. THE FRONT SHOULD COME THROUGH DRY GIVEN THE LACK
OF DEEP MOISTURE AND LIFT AND THE PRECEDING DOWNSLOPE NORTHWESTERLY
925 MB FLOW. THE KY/TN CONVECTIVE COMPLEX IS LIKELY TO DISSIPATE
CROSSING THE SRN APPALACHIANS EARLY FRIDAY AS THE MID LEVEL
PERTURBATION DAMPENS OUT AND SKIRTS TO OUR SW... BUT WE SHOULD STILL
SEE A PERIOD OF THICKER CLOUDS PARTICULARLY OVER THE WRN AND SRN CWA
FRIDAY AS THE REMNANT CLOUDS PASS OVER NC... THUS EXPECT PARTLY
SUNNY TO MOSTLY CLOUDY SKIES FOR A PORTION OF THE DAY AS MODELS
DEPICT INCREASING LOW LEVEL THETA-E BENEATH THE WARM/STABLE LAYER
ALOFT (AROUND 700 MB). HAVE TRIMMED A COUPLE OF DEGREES OFF FORECAST
HIGHS... TO 71-76. AS THE FRONT DROPS THROUGH THE AREA IN THE
EVENING... SURFACE WINDS WILL VEER AROUND TO NORTHEASTERLY AND COULD
BE RATHER GUSTY IMMEDIATELY BEHIND THE FRONT. THE STABILIZATION IN
THE LOWEST 200 MB (AROUND 2 KM) CAPPED BY MID LEVEL
SUBSIDENCE/WARMING AND THE HIGH THETA-E TRAPPED IN THE UPPER
PORTIONS OF THIS STABLE LAYER SHOULD RESULT IN SCATTERED TO BROKEN
CLOUDS FOR MUCH OF THE NIGHT. LOWS FROM 41 NORTH TO 47 SOUTH WITH
STRONG LOW LEVEL COLD AIR ADVECTION OVERNIGHT. -GIH
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 250 AM WEDNESDAY...
FOR SATURDAY/SATURDAY NIGHT: DRY AND COOL. NORTHWESTERLY MID LEVEL
FLOW DIMINISHES AND BACKS TO WSW AS RIDGING BUILDS OVER THE
SOUTHEAST... IN RESPONSE TO THE CLOSED LOW NOW OFF THE CENTRAL CA
COAST EJECTING NORTHEASTWARD AS AN OPEN WAVE THROUGH THE PLAINS. AT
THE SURFACE... THE CHILLY SURFACE HIGH TO OUR NORTH CONTINUES TO
NOSE INTO NC AS IT PROGRESSES STEADILY EASTWARD OFF THE MIDATLANTIC
COAST. THE COLUMN REMAINS DRY AND SUBSIDING... AND EXPECT ONLY A FEW
FLAT STRATOCUMULUS CLOUDS. THE SHALLOW MIXED LAYER SUPPORTS
BELOW-NORMAL HIGHS OF 65-71. AS THE SURFACE HIGH CENTER SHIFTS
FURTHER OUT OVER THE ATLANTIC WITH THE RIDGE STILL EXTENDING BACK
INTO NC... THE RETURN FLOW AND INCREASING FETCH OF LOW LEVEL
ATLANTIC MOISTURE COMBINED WITH THE NIGHTTIME COOLING/STABILIZATION
SUPPORTS POCKETS OF FOG AND STRATUS DEVELOPMENT SATURDAY NIGHT. LOWS
48-52.
FOR SUNDAY THROUGH TUESDAY: THE AFOREMENTIONED OPEN WAVE DAMPENS A
BIT MORE AS IT MOVES EAST OVER NRN SECTIONS OF THE GREAT LAKES
SUNDAY... ALTHOUGH AN INJECTION OF POLAR STREAM ENERGY FROM
SASKATCHEWAN IS APT TO RESTRENGTHEN THE SHORTWAVE TROUGH SOMEWHERE
OVER THE ST LAWRENCE VALLEY BY LATE MONDAY. MODELS DISAGREE ON
EXACTLY WHERE THE SHORTWAVE TROUGH WILL MOVE AND HOW DEEP IT WILL BE
(THE ECMWF IS SLOWER/DEEPER THAN THE LAST TWO RUNS OF THE GFS).
WE`LL FIRST SEE THE LEE TROUGH DEEPEN OVER CENTRAL NC SUNDAY WITH
WARMING THICKNESSES... THEN A COLD FRONT WILL LIKELY APPROACH NC
FROM THE NNW... EARLY MONDAY ON THE GFS AND NOT UNTIL EARLY TUESDAY
ON THE ECMWF. GIVEN THIS STARK DIFFERENCE IN SOLUTIONS WITH REDUCED
CONFIDENCE GIVEN THE FAST MID LEVEL FLOW TO OUR NORTH... WILL MAKE
FEW CHANGES... HOLDING ONTO ABOVE-NORMAL TEMPS. WILL INCLUDE A
MENTION OF AN ISOLATED SHOWER CHANCE ON MONDAY/MONDAY NIGHT WITH
FRONTAL PASSAGE AS LOW LEVEL MOISTURE WILL HAVE INCREASED
SUFFICIENTLY DUE TO THE ATLANTIC INFLOW. WHICHEVER MODEL SOLUTION
ENDS UP MORE CORRECT (IF EITHER)... THE TRUE POLAR AIR WILL BE
LOCKED UP IN THE FAR NRN TIER AND CANADA... THUS NO WIDE SWINGS IN
TEMPS ARE EXPECTED EITHER WAY... AND THE LIMITED GULF MOISTURE WILL
FAVOR LOW PRECIP CHANCES. -GIH
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 150 AM AM WEDNESDAY...
24-HR TAF PERIOD:
MVFR/IFR CEILINGS CONTINUE TO PLAGUE A LARGE PORTION OF CENTRAL NC
AS OF 05Z. SOME SCATTERING OF LOW CLOUDS HAS ALREADY TAKEN PLACE
AROUND KINT/KGSO...WITH CEILINGS HOVERING JUST ABOVE 3K FT.
HOWEVER...SHOULD WINDS REMAIN VERY LIGHT...THE DRYING JUST ABOVE THE
SURFACE MAY LEAD TO FOG AND/OR VERY LOW STRATUS BETWEEN 09Z-12Z.
FURTHER EAST...CONDITIONS WILL REMAIN AT LEAST MVFR THROUGH
12Z...WITH A PERIOD OF IFR CEILINGS/VSBYS ALSO POSSIBLE BETWEEN
09Z-12Z. DRIER AIR SURGING INTO THE AREA FROM THE SOUTH AND WEST
SHOULD THEN SCOUR OUT THE REMAINING LOW CLOUDS FAIRLY RAPIDLY AFTER
12Z...WITH VFR CONDITIONS EXPECTED BY 15Z.
A STEADY 8-12KT WESTERLY WIND WILL DEVELOP THIS AFTERNOON...BACKING
SLIGHTLY TO SOUTHWESTERLY THIS EVENING AS A DRY COLD FRONT MOVES
INTO THE AREA FROM THE NORTHWEST AFTER 00Z. VFR CONDITIONS WILL
PERSIST THROUGH THE FRONTAL PASSAGE AS WINDS TURN TO NORTHWESTERLY
BEHIND THE FRONT.
OUTLOOK...
VFR CONDITIONS ARE EXPECTED THROUGH THIS WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BLS
NEAR TERM...BLS
SHORT TERM...HARTFIELD
LONG TERM...HARTFIELD
AVIATION...BLS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
245 AM EDT WED OCT 10 2012
.SYNOPSIS...
DRIER AIR WILL SPREAD INTO THE AREA FROM THE WEST TODAY...LEADING TO
ABUNDANT SUNSHINE AND MUCH WARMER TEMPERATURES. A DRY COLD FRONT
WILL THEN SWEEP THROUGH THE AREA LATE THIS EVENING AND BRING
TEMPERATURES BACK DOWN BELOW SEASONAL NORMALS FOR THURSDAY.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 245 AM WEDNESDAY...
STRATUS REMAINS LOCKED IN BELOW THE INVERSION AT 850MB THIS
MORNING...ALTHOUGH THERE IS A WEST-SOUTHWESTERLY PUSH OF DRIER LOW
LEVEL AIR BEGINNING TO WORK ITS WAY UP FROM SC ND SOUTHWESTERN
NC WHERE STRATUS IS BEGINNING TO CLEAR. IMMEDIATELY BEHIND THE
CLEARING LINE...WHICH CURRENTLY STRETCHES FROM KEHO TO KFLO...LIGHT
SURFACE WINDS AND COOLING MAY PROMOTE SOME LOCALIZED FOG AND LOW
CLOUDS JUST PRIOR TO SUNRISE. MEANWHILE...DEEP WESTERLY FLOW WILL
BECOME ESTABLISHED OVER AREA AS A LOW PRESSURE SYSTEM CROSSES THE
NORTHERN GREAT LAKES REGION AND THE UPPER TROUGH AXIS SHIFTS EAST
THE OH VALLEY REGION. RAP SOUNDINGS SHOW A RELATIVELY RAPID
CLEARING OF LOW CLOUDS ACROSS THE PIEDMONT AND COASTAL PLAIN BY
AROUND 14-16Z. THUS... MUCH OF THE DAY WILL FEATURE MOSTLY SUNNY
SKIES. A PLUME OF PREFRONTAL MOISTURE AHEAD OF A COLD FRONT
CURRENTLY CROSSING IL/MO IS FORECAST UNDERGO QUITE A BIT OF DRYING
AS IT ENCOUNTERS THE MOUNTAINS THIS AFTERNOON. HOWEVER...
CROSS-SECTIONS SUGGEST THERE MAY BE ENOUGH MOISTURE FOR A SCATTERED
CUMULUS FIELD TO DEVELOP IN THE LEE TROUGH OVER THE WESTERN PIEDMONT
THIS AFTERNOON. OTHERWISE...UNDER FULL SUN AND A WEAK WESTERLY
DOWNSLOPE WIND COMPONENT...DRY ADIABATIC MIXING TO NEAR 850MB YIELDS
HIGHS IN THE LOW TO MID 70S FROM WEST TO EAST.
TONIGHT...
THE AFOREMENTIONED DRY COLD FRONT WILL CROSS THE AREA BETWEEN 00Z
AND 06Z THIS EVENING...WITH ONLY A FEW CLOUDS ACCOMPANYING THE
FROPA. POST-FRONTAL COLD ADVECTION WILL DRIVE LOWS INTO THE LOW TO
MID 40S...THOUGH THE MAV MOS SHOWS UPPER 30S ACROSS THE NORTHERN
PIEDMONT. HOWEVER...A LIGHT WIND AND DRYING THROUGH 12Z SHOULD
PRECLUDE ANY FROST.
THURSDAY...
HIGH PRESSURE WILL SETTLE ACROSS WV AND WEAKEN OVER VA/NC THURSDAY
AFTERNOON...WHILE ANOTHER WEAK COLD FRONT MOVES INTO THE OH VALLEY.
1000-850MB THICKNESSES ARE FORECAST TO BE AROUND 1335M AT 12Z
THURSDAY...WHICH YIELDS MOST MID AND UPPER 60S BASED ON CLIMATOLOGY.
&&
.SHORT TERM /THURSDAY NIGHT/...
AS OF 115 PM TUESDAY...
THE SURFACE RIDGING IS FORECAST TO LINGER INTO THURSDAY NIGHT...
ESPECIALLY IN THE NE ZONES. HOWEVER... THE NEXT COLD FRONT WILL
APPROACH EARLY FRIDAY. THIS FRONT WILL BE DRIVEN BY A DECENT VORT
MAX IN THE WNW FLOW ALOFT WHICH IS EXPECTED TO BE APPROACHING THE
CENTRAL APPALACHIANS LATE THURSDAY NIGHT. SOME HIGH AND MID CLOUDS
SHOULD ARRIVE IN THE PRE-DAWN HOURS ESPECIALLY ACROSS THE WEST AND
NORTH. THIS ALONG WITH A LIGHT RETURN SW FLOW JUST ABOVE THE SURFACE
SHOULD KEEP THE TEMPERATURES FROM FALLING TO THE FROST POINT IN THE
NW AND N PIEDMONT. IT APPEARS THAT THE COLDEST READINGS SHOULD BE
FOUND IN THE NE ZONES WHERE IT MAY REMAIN CLEAR AND CALM ALL NIGHT.
THERE MAY BE SOME VERY PATCHY FROST MAINLY IN THE NE ZONES FROM
ROXBORO TO ROANOKE RAPIDS WITH LOWS IN THE MID TO UPPER 30S THERE.
ELSEWHERE... LOWS SHOULD BE AROUND 40... WITH A SLOW RISE LATE AT
NIGHT DUE TO THE INCREASE IN CLOUDS ACROSS THE WESTERN PIEDMONT.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 100 PM TUESDAY...
FRIDAY THROUGH SATURDAY...
ANOTHER DRY COLD FRONT IS SLATED TO PUSH ACROSS NC FRIDAY. WAA WILL
BE OFFSET BY AT LEAST SOME MID/UPPER CLOUDINESS. STILL... HIGHS
SHOULD REBOUND BACK INTO THE LOWER TO MID 70S. WINDS WILL GRADUALLY
SHIFT FROM W TO NNE BY LATE IN THE DAY. THE SURFACE HIGH IS FORECAST
TO DELIVER DRY/COOL ADVECTION FRI NIGHT AND SATURDAY AS IT MOVES
FROM THE MIDWEST TO THE MID-ATLANTIC REGION BY SATURDAY. MOSTLY
CLEAR/MOSTLY SUNNY WEATHER IS EXPECTED. LOWS 40-45. HIGHS 67-72.
SUNDAY THROUGH TUESDAY...
A DECIDED WARMING TREND IS FORECAST AS THE MID-UPPER FLOW BECOMES
MORE ZONAL AND THE HIGH PRESSURE RETREATS QUICKLY OFFSHORE SAT NIGHT
AND SUNDAY. MOSTLY CLEAR/MOSTLY SUNNY SKIES ARE FORECAST THROUGH
SUNDAY WITH LOWS 45-50. HIGHS SUNDAY 75-80. MILD TO WARM CONDITIONS
SHOULD PERSIST MONDAY AND TUESDAY UNDER FLAT MID-UPPER RIDGING AND A
SW LOW LEVEL FLOW. THE BEST CHANCE OF SHOWERS SHOULD REMAIN WEST OF
THE MOUNTAINS WITH THE MAIN STORM TRACK WELL TO OUR WEST AND NORTH
THROUGH EARLY WEEK. LOWS 55-60 MONDAY AND TUESDAY. HIGHS 75-82.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 150 AM AM WEDNESDAY...
24-HR TAF PERIOD:
MVFR/IFR CEILINGS CONTINUE TO PLAGUE A LARGE PORTION OF CENTRAL NC
AS OF 05Z. SOME SCATTERING OF LOW CLOUDS HAS ALREADY TAKEN PLACE
AROUND KINT/KGSO...WITH CEILINGS HOVERING JUST ABOVE 3K FT.
HOWEVER...SHOULD WINDS REMAIN VERY LIGHT...THE DRYING JUST ABOVE THE
SURFACE MAY LEAD TO FOG AND/OR VERY LOW STRATUS BETWEEN 09Z-12Z.
FURTHER EAST...CONDITIONS WILL REMAIN AT LEAST MVFR THROUGH
12Z...WITH A PERIOD OF IFR CEILINGS/VSBYS ALSO POSSIBLE BETWEEN
09Z-12Z. DRIER AIR SURGING INTO THE AREA FROM THE SOUTH AND WEST
SHOULD THEN SCOUR OUT THE REMAINING LOW CLOUDS FAIRLY RAPIDLY AFTER
12Z...WITH VFR CONDITIONS EXPECTED BY 15Z.
A STEADY 8-12KT WESTERLY WIND WILL DEVELOP THIS AFTERNOON...BACKING
SLIGHTLY TO SOUTHWESTERLY THIS EVENING AS A DRY COLD FRONT MOVES
INTO THE AREA FROM THE NORTHWEST AFTER 00Z. VFR CONDITIONS WILL
PERSIST THROUGH THE FRONTAL PASSAGE AS WINDS TURN TO NORTHWESTERLY
BEHIND THE FRONT.
OUTLOOK...
VFR CONDITIONS ARE EXPECTED THROUGH THIS WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BSD/BLS
NEAR TERM...BLS
SHORT TERM...VINCENT/BADGETT
LONG TERM...BADGETT
AVIATION...BLS
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
145 PM CDT WED OCT 10 2012
.DISCUSSION...
REGIONAL RADAR RETURNS SEEM TO BE DIMINISHING A BIT AND UPSTREAM
WEB CAMS SHOW LITTLE TO NOTHING OTHER THAN WET GROUND. WILL
THEREFORE UPDATE AGAIN AND REMOVE ANY SNOW ACCUMULATIONS IN THE
FAR NORTH. COULD STILL BE SOME RAIN/SNOW MIX BUT OVERALL EVEN PCPN
AMOUNTS SHOULD BE LESS THAN PREVIOUSLY EXPECTED.
&&
.AVIATION...
MOSTLY VFR CONDITIONS ARE EXPECTED FOR TODAY. COULD BE SOME MVFR
CONDITIONS WITH THE RAIN/SNOW MOVING THROUGH THE AREA THIS
AFTERNOON INTO THE EVENING.
&&
.PREV DISCUSSION... /ISSUED 1011 AM CDT WED OCT 10 2012/
DISCUSSION...
WILL BE WATCHING PCPN HEADING INTO THE FA LATE THIS MORNING AND
CONTINUING INTO THE AFTERNOON. MAIN QUESTIONS WILL BE PCPN TYPE
AND WHETHER THE SNOW WILL ACCUMULATE. RIGHT NOW HAVE A MIX OF
LIGHT RAIN AND LIGHT SNOW FALLING AT MINOT WITH LIGHT SNOW UP IN
THE FAR NORTHWEST CORNER OF ND AND IN THE SOUTHEAST CORNER OF
SASKATCHEWAN. SHORT TERM MODELS HAVE STRUGGLED A LITTLE WITH
EXACTLY WHERE THE MOST PCPN WILL FALL AND THIS IS ALWAYS TOUGH
WHEN IT COULD BE SUCH A THIN BAND. LATEST NAM AND RAP DO NOT
DEVIATE TOO MUCH FROM WHAT THE FORECAST HAS GOING...KEEPING THE
MAIN BAND KIND OF ALONG THE HIGHWAY 2 CORRIDOR. SEEING A LITTLE
SUNSHINE NOW AND HOPEFULLY THIS WILL HELP WARM THINGS UP ENOUGH
FOR MOST OF THE FA SO IT WILL STAY AS RAIN. TEMPS WILL BE THE
COLDEST UP ALONG THE CANADIAN BORDER WHERE THICKER CLOUDS WILL
PROBABLY KEEP TEMPS FROM WARMING MUCH. WILL KEEP THE MENTION OF A
MIX OF RAIN/SNOW IN THIS AREA AND MONITOR IF ANY EXPANDING OF THE
SNOW AREA NEEDS TO BE MADE. COULD BE SOME WHITE ACCUMULATION IN
GRASSY AREAS IN THIS AREA TOO. IF PCPN BAND GOES FURTHER SOUTH
WOULD ALSO HAVE TO ADJUST THE FORECAST LATER.
PREV DISCUSSION... /ISSUED 430 AM CDT WED OCT 10 2012/
SHORT TERM...TODAY THROUGH FRIDAY NIGHT.
GFS HAS SHIFTED SOUTH WITH PRECIP SINCE YESTERDAYS RUN. THE NAM AND
AND ECMWF HAVE SHIFTED TO A NORTHERN SOLUTION SINCE YESTERDAY. WILL
USE A CONSENSUS OF THE MODELS FOR TODAY. WATER VAPOR LOOP INDICATED
UPPER LEVEL JET EXTENDED FROM AK TO IA. UPPER LEVEL JET WILL MOVE
ACROSS THE FORECAST AREA FOR TODAY THROUGH THU BEFORE SHIFTING EAST
OF THE AREA. UPPER AIR PATTERN FLATTENS THIS PERIOD.
MOST OF THE MODEL SOUNDINGS ARE UNDER ZERO CELSIUS FOR TODAY.
WILL KEEP A MIX OF RAIN AND SNOW FOR TODAY WITH SOME DYNAMIC
COOLING. WILL GO FOR AN INCH OR SO OF WET SNOW FOR TODAY. LIGHT RAIN
OR SNOW MOVES MOSTLY INTO MN THIS EVENING. SOME WRAP AROUND
PRECIPITATION IN THE FAR NORTHEAST ZONES ON THU. THE NEXT OF
PRECIPITATION IS EXPECTED LATE FRI NIGHT IN THE SOUTHEAST ZONES.
LONG TERM (SAT-TUE)...
MODELS CONTINUE TO BE IN SOMEWHAT FAIR AGREEMENT WITH THE LONG TERM
AND THE CENTRAL PLAINS STORM SYSTEM FOR THE WEEKEND. BOTH YESTERDAYS
12Z AND NOW TODAYS 00Z MODEL RUNS HAVE LESSENED THE QPF ON SATURDAY
IN THE SOUTHEAST PORTIONS OF THE AREA. MODELS HAVE REALLY TRENDED TO
THE SE WITH PCPN PLACEMENT ENOUGH SO THAT THE SE ZONES MAY BE
COMPLETELY DRY...WILL REDUCE LIKELY POPS DOWN TO CHC AND CONTINUE TO
MONITOR PLACEMENT TRENDS. WITH THE MORE SOUTHERLY TRACK OF THE
SYSTEM MORE SUN EXPECTED SATURDAY AND HIGHS A BIT WARMER AS A
RESULT...ESPECIALLY IN THE WEST AND NORTH.
ON SUNDAY 00Z MODELS DIVERGE A BIT WITH TIMING AND PLACEMENT OF WEAK
SHORT WAVES IN THE FAST QUASI ZONAL 500MB FLOW THRU TUESDAY. KEPT
WEAK POPS IN THE FORECAST FROM SUN NIGHT TO TUESDAY...WITH TEMPS
CONTINUING TO BE NEAR NORMAL FOR MID OCTOBER.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
GODON
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
1011 AM CDT WED OCT 10 2012
.DISCUSSION...
WILL BE WATCHING PCPN HEADING INTO THE FA LATE THIS MORNING AND
CONTINUING INTO THE AFTERNOON. MAIN QUESTIONS WILL BE PCPN TYPE
AND WHETHER THE SNOW WILL ACCUMULATE. RIGHT NOW HAVE A MIX OF
LIGHT RAIN AND LIGHT SNOW FALLING AT MINOT WITH LIGHT SNOW UP IN
THE FAR NORTHWEST CORNER OF ND AND IN THE SOUTHEAST CORNER OF
SASKATCHEWAN. SHORT TERM MODELS HAVE STRUGGLED A LITTLE WITH
EXACTLY WHERE THE MOST PCPN WILL FALL AND THIS IS ALWAYS TOUGH
WHEN IT COULD BE SUCH A THIN BAND. LATEST NAM AND RAP DO NOT
DEVIATE TOO MUCH FROM WHAT THE FORECAST HAS GOING...KEEPING THE
MAIN BAND KIND OF ALONG THE HIGHWAY 2 CORRIDOR. SEEING A LITTLE
SUNSHINE NOW AND HOPEFULLY THIS WILL HELP WARM THINGS UP ENOUGH
FOR MOST OF THE FA SO IT WILL STAY AS RAIN. TEMPS WILL BE THE
COLDEST UP ALONG THE CANADIAN BORDER WHERE THICKER CLOUDS WILL
PROBABLY KEEP TEMPS FROM WARMING MUCH. WILL KEEP THE MENTION OF A
MIX OF RAIN/SNOW IN THIS AREA AND MONITOR IF ANY EXPANDING OF THE
SNOW AREA NEEDS TO BE MADE. COULD BE SOME WHITE ACCUMULATION IN
GRASSY AREAS IN THIS AREA TOO. IF PCPN BAND GOES FURTHER SOUTH
WOULD ALSO HAVE TO ADJUST THE FORECAST LATER.
&&
.AVIATION...
MOSTLY VFR CONDITIONS ARE EXPECTED FOR TODAY. SOME MVFR
CONDITIONS POSSIBLE WITH RAIN/SNOW MOVING THROUGH THE AREA THIS
AFTERNOON INTO THE EVENING.
&&
.PREV DISCUSSION... /ISSUED 430 AM CDT WED OCT 10 2012/
SHORT TERM...TODAY THROUGH FRIDAY NIGHT.
GFS HAS SHIFTED SOUTH WITH PRECIP SINCE YESTERDAYS RUN. THE NAM AND
AND ECMWF HAVE SHIFTED TO A NORTHERN SOLUTION SINCE YESTERDAY. WILL
USE A CONSENSUS OF THE MODELS FOR TODAY. WATER VAPOR LOOP INDICATED
UPPER LEVEL JET EXTENDED FROM AK TO IA. UPPER LEVEL JET WILL MOVE
ACROSS THE FORECAST AREA FOR TODAY THROUGH THU BEFORE SHIFTING EAST
OF THE AREA. UPPER AIR PATTERN FLATTENS THIS PERIOD.
MOST OF THE MODEL SOUNDINGS ARE UNDER ZERO CELSIUS FOR TODAY.
WILL KEEP A MIX OF RAIN AND SNOW FOR TODAY WITH SOME DYNAMIC
COOLING. WILL GO FOR AN INCH OR SO OF WET SNOW FOR TODAY. LIGHT RAIN
OR SNOW MOVES MOSTLY INTO MN THIS EVENING. SOME WRAP AROUND
PRECIPITATION IN THE FAR NORTHEAST ZONES ON THU. THE NEXT OF
PRECIPITATION IS EXPECTED LATE FRI NIGHT IN THE SOUTHEAST ZONES.
LONG TERM (SAT-TUE)...
MODELS CONTINUE TO BE IN SOMEWHAT FAIR AGREEMENT WITH THE LONG TERM
AND THE CENTRAL PLAINS STORM SYSTEM FOR THE WEEKEND. BOTH YESTERDAYS
12Z AND NOW TODAYS 00Z MODEL RUNS HAVE LESSENED THE QPF ON SATURDAY
IN THE SOUTHEAST PORTIONS OF THE AREA. MODELS HAVE REALLY TRENDED TO
THE SE WITH PCPN PLACEMENT ENOUGH SO THAT THE SE ZONES MAY BE
COMPLETELY DRY...WILL REDUCE LIKELY POPS DOWN TO CHC AND CONTINUE TO
MONITOR PLACEMENT TRENDS. WITH THE MORE SOUTHERLY TRACK OF THE
SYSTEM MORE SUN EXPECTED SATURDAY AND HIGHS A BIT WARMER AS A
RESULT...ESPECIALLY IN THE WEST AND NORTH.
ON SUNDAY 00Z MODELS DIVERGE A BIT WITH TIMING AND PLACEMENT OF WEAK
SHORT WAVES IN THE FAST QUASI ZONAL 500MB FLOW THRU TUESDAY. KEPT
WEAK POPS IN THE FORECAST FROM SUN NIGHT TO TUESDAY...WITH TEMPS
CONTINUING TO BE NEAR NORMAL FOR MID OCTOBER.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
GODON
AREA FORECAST DISCUSSION
NWS BISMARCK ND
700 AM CDT WED OCT 10 2012
.DISCUSSION...SURFACE LOW PRESSURE CURRENTLY OVER SOUTHWEST
SASKATCHEWAN WILL MOVE SOUTHEAST ACROSS WESTERN AND SOUTH CENTRAL
NORTH DAKOTA TODAY BRINGING RAIN AND SNOW SHOWERS TO MAINLY
NORTHWEST AND NORTH CENTRAL PORTIONS OF THE LOCAL AREA. LATEST NAM
AND RUC MODELS...ALONG WITH THE ECMWF INDICATE A MORE NORTHWARD
POSITION OF THE SURFACE LOW AS IT TRACKS ACROSS THE STATE. THE GFS
IS FARTHER SOUTH WITH ITS POSITION. THE DIFFERENCES ARE MINIMAL
AND WOULD RESULT IN A BIT MORE SOUTHWARD PLACEMENT OF
PRECIPITATION WITH A GFS SOLUTION. WILL LEAN TOWARD THE
NAM/ECMWF/RUC SOLUTION FOR NOW WHICH IS SIMILAR TO THE GOING
FORECAST. ONLY MINIMAL CHANGES TO THE CURRENT FORECAST...MAINLY TO
LOWER CLOUD COVER OVER THE FAR SOUTHWEST AND POPULATE WITH THE
LATEST CURRENT OBSERVATIONS.
&&
.AVIATION...A LOW PRESSURE SYSTEM OVER SOUTHWEST SASKATCHEWAN WILL
MOVE SOUTHEAST INTO WESTERN NORTH DAKOTA TODAY...THEN EXIT SOUTH
CENTRAL NORTH DAKOTA THIS EVENING. WEST TO SOUTHWEST SURFACE FLOW
AHEAD OF THE SYSTEM WILL SHIFT NORTH IN THE WAKE OF THE LOW.
MAINLY MID LEVEL VFR CLOUDINESS IS EXPECTED WITH THIS SYSTEM.
HOWEVER...AREAS OF MVFR CEILINGS AND VISIBILITIES ARE POSSIBLE
MAINLY NORTH OF A LINE FROM KISN TO KJMS. UPPER LEVEL SUPPORT IN
THIS REGION WILL PRODUCE A BAND OF RAIN/SNOW SHOWERS THAT TRACKS
FROM NORTHWEST NORTH DAKOTA THIS MORNING...INTO THE EAST CENTRAL
PORTION OF THE STATE BY LATE AFTERNOON. WILL HIT LOWER CEILINGS
AND VISIBILITIES HARDEST AT KMOT EARLY THIS AFTERNOON.
PRECIPITATION SHOULD EXIT THE AREA BY EARLY EVENING WITH
DECREASING CLOUDS AND WINDS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM NOON CDT /11 AM MDT/ TODAY TO 9 PM CDT /8
PM MDT/ THIS EVENING FOR NDZ040>045.
&&
$$
TWH
AREA FORECAST DISCUSSION
NWS NORMAN OK
335 PM CDT WED OCT 10 2012
.DISCUSSION...
STRATUS CONTINUES TO SPREAD NORTH ACROSS THE AREA AND EXPECT
OVERCAST SKIES AREAWIDE BY MID-LATE EVENING. HRRR HAS SOME SIGNAL
THAT CLEARING OVER CENTRAL TEXAS NOW MAY SPREAD INTO NORTH TEXAS
ZONES LATE TONIGHT... BUT MOST SIGNAL IS FOR STRATUS PERSISTANCE
OR REDEVELOPMENT WITH THIS LOW-LEVEL MOISTURE ADVECTION... SO WILL
JUST KEEP THE OVERCAST SKIES THROUGHOUT. MAY SEE SOME LIGHT
SHOWERS DEVELOP OVERNIGHT AS LOW-LEVEL MOISTURE INCREASES.
STORM CHANCES INCREASE THURSDAY NIGHT AND PERSIST THROUGH AT LEAST
SATURDAY AS EXPECTED WITH /A/ THE ARRIVAL OF A COLD FRONT MOVING
SOUTH THROUGH THE CENTRAL PLAINS IN RESPONSE TO A STORM SYSTEM
SWINGING THROUGH THE GREAT LAKES.. AND /B/ THE STORM SYSTEM
CURRENTLY ON THE SOUTHERN CALIFORNIA COAST MOVING TOWARD THE
PLAINS. NO REAL SIGNIFICANT CHANGE IN THE EXPECTATIONS FROM THE
PREVIOUS FORECAST WITH THIS SYSTEM... SO HAVE ONLY MADE MINOR
CHANGES TO THE FORECAST.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 55 80 65 83 / 20 20 40 50
HOBART OK 52 80 64 81 / 20 20 40 40
WICHITA FALLS TX 58 84 67 85 / 20 20 20 20
GAGE OK 50 84 58 75 / 10 20 40 50
PONCA CITY OK 54 81 61 76 / 20 20 60 50
DURANT OK 58 82 65 85 / 20 20 20 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AGREEMENT WITH MORNING FORECAST DISCUSSION THAT IT IS CERTAINLY NOT
OUT OF THE QUESTION THAT A SQUALL LINE COULD DEVELOP IN THE FRONTAL
VCNTY...ESPECIALLY DURING THE MORNING HRS ON SUN...WITH DAMAGING
WINDS BEING A CONCERN. MOISTURE RETURN ALSO LOOKS TO BE QUESTIONABLE
WITH THIS SYSTEM TOO...ALTHOUGH BRIEF HEAVY RAINFALL WITH THE
STRONGER SHWRS AND TSTMS THAT DEVELOP IS CERTAINLY ALSO NOT OUT OF
THE QUESTION. ACTUAL TIMING OF ALL THE FEATURES NEEDED FOR A
POTENTIAL SVR WX OUTBREAK TO DEVELOP WILL BE A KEY HERE...BUT AT
THIS TIME THERE CONTINUES TO BE TOO MUCH UNCERTAINTY OVERALL...AND
WILL THUS LEAN TOWARD THE REASONING OF THE LATEST SPC DAY 4-8
CONVECTIVE OUTLOOK...AS THEY CONTINUE TO NOT MENTION THE MID STATE
OR ANY OTHER AREA ACROSS THE ERN U.S. IN ANY REGIONAL WX OUTLOOK FOR
SUN.
OTHERWISE...WILL GO CLOSE TO FORECAST REASONING FROM THIS MORNING ALSO...
AND BELIEVE THAT SOME SHWRS WILL LINGER ACROSS THE PLATEAU REGION THRU
EARLY MON. MODELS COMING MORE INTO LINE WITH THE NEXT SIGNIFICANT COLD
FRONTAL PASSAGE MID TO LATE NEXT WEEK.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
01
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
959 PM CDT THU OCT 11 2012
.UPDATE...
9 PM SATELLITE AND RADAR DATA SHOW A BATCH OF SHOWERS AND ISOLD
TSTMS MOVING NEWD FROM EASTERN NM INTO THE WESTERN TX
PANHANDLE...BYPASSING OUR CWA EXCEPT PERHAPS FOR PARMER COUNTY.
SFC OBS SHOW A FRONT JUST MOVING INTO THE NRN TX PANHANDLE. AS THE
FRONT MOVES SOUTH...THE CURRENT ACTIVITY MAY GET A BIT OF A BOOST
FROM LIFT ALONG THE FRONT. MOST OF THIS ACTIVITY SHOULD REMAIN TO
OUR NORTH...BUT COULD SINK SWD INTO OUR NRN ZONES AFTER MIDNIGHT.
THE HRRR HAS BEEN ADVERTISING SCT TSTMS MOVING INTO OUR SW ZONES
AFTER MIDNIGHT FOR SEVERAL RUNS NOW...BUT IT/S DEPICTION OF CURRENT
ACTIVITY IN SE NM AND FAR WEST TEXAS SEEMS OVERDONE...LOWERING
CONFIDENCE IN IT/S FORECAST.
THE 0Z NAM HAS ARRIVED. IT HINTS THAT THERE COULD BE TWO ROUNDS OF
STORMS. THE FIRST ROUND OF STORMS FIRING OFF THE HIER TERRAIN OF
NM BY EARLY AFTERNOON...EVENTUALLY PASSING THROUGH MOST OF THE
CWA FRIDAY EVENING. THEN ANOTHER LINE OF STORMS LATE FRIDAY
NIGHT/SAT MORNING FORCED ALONG A PACIFIC-TYPE FRONT SWEEPING
ACROSS THE FA. FCST SNDGS STILL INDICATE POTENTIAL FOR SEVERE
WEATHER FRIDAY AFTERNOON AND EVENING. THE SOUNDING AT LUBBOCK
SUGGESTS THAT SKIES COULD VERY WELL PARTIALLY CLEAR OUT ALLOWING
SBCAPES TO RISE TO NEAR 2000 J/KG AND TEMPS TO SUFFICIENTLY WARM
FOR SURFACE-BASED CONVECTION. SHEAR APPEARS FAIRLY UNIDRECTIONAL
AT LUBBOCK...BUT WILL LIKELY EXHIBIT MORE TURNING ACROSS THE FAR
SRN TX PANHANDLE.
NO CHANGES IN FCST FOR NOW...WILL WAIT AND SEE WHAT THE 0Z GFS
BRINGS.
&&
.PREV DISCUSSION... /ISSUED 633 PM CDT THU OCT 11 2012/
AVIATION...
VFR CONDITIONS WILL PREVAIL AT BOTH TERMINALS DURING THE OVERNIGHT
HOURS. VIS SAT SHOWS A CLUSTER OF CLOUDS BEGINING TO MOVE INTO THE
KCDS AREA...WHICH SHOULD BRING THE CIGS FROM FEW TO BKN
SHORTLY...BUT WILL REMAIN IN THE VFR CATEGORY. ISOLATED TO
SCATTERED CONVECTION WILL MOVE INTO THE AREA LATE THIS EVENING
WHICH COULD IMPACT EITHER TERMINAL. AND STORMS AFFECTING A
TERMINAL COULD BRING CIGS TO MVFR...IFR AT WORST...FOR A SHORT
PERIOD OF TIME. WINDS WILL ALSO BE GUSTY TONIGHT WITH GUSTS TO 25
KTS. CIGS WILL BECOME LOW END MVFR TOWARDS MORNING IN RESPONSE TO
ABUDUNT LOW LEVEL MOISTURE MOVING INTO THE AREA. BIG AREA OF
CONCERN WILL BE TOMORROW AFTERNOON WITH THE POSSIBILITY OF STRONG
TO SEVERE THUNDERSTORMS AFFECTING THE FA. HAIL WILL BE THE PRIMARY
THREAT FOR THUNDERSTORMS...BUT MAY ALSO HAVE SEVERE WIND GUSTS AS
WELL.
PREV DISCUSSION... /ISSUED 350 PM CDT THU OCT 11 2012/
SHORT TERM...
ONGOING CONVECTION ORIGINATING DURING THE LATE AFTERNOON/EARLY
EVENING ACROSS THE EXTREME SOUTHWESTERN TEXAS PANHANDLE WILL PUSH
EAST OVERNIGHT AND LOSE INTENSITY AS IT TRIES TO MOVE INTO THE
SOUTHERN HALF OF THE ROLLING PLAINS. THIS IS DUE TO A MID-LEVEL
SHORTWAVE TROUGH INTERACTING WITH RICH BOUNDARY LAYER MOISTURE AS
EVIDENCED BY DEWPOINTS IN THE LOW 60S. DEEP LAYER INSTABILITY WILL
BE HIGHEST NEAR THE NEW MEXICO STATE LINE AS GREATER MIXING THIS
AFTERNOON SOMEWHAT ALLEVIATES A SHALLOW NEAR-SURFACE COLD POOL WHICH
WILL INHIBIT CONVECTION FARTHER SOUTH AND EAST. A 35 KNOT LOW-LEVEL
JET WILL STRENGTHEN WIND FIELDS AND PROMOTE THE CHANCE FOR CONTINUING
CONVECTION THROUGHOUT THE NIGHT. AREAS ACROSS THE SOUTHEASTERN
ROLLING PLAINS WILL SEE SOME PATCHY FOG FOR A FEW HOURS TOMORROW
MORNING NEAR SUNRISE AS ABUNDANT MOISTURE REMAINS TRAPPED IN A
FAIRLY STABLE NOCTURNAL BOUNDARY LAYER.
A MID-UPPER LEVEL LOW PRESSURE CENTER WILL EJECT NORTHEASTWARD FROM
OFF THE SOUTHERN CALIFORNIA COAST AND MOVE TOWARD THE ROCKY MOUNTAIN
REGION AND CENTRAL GREAT PLAINS. THIS FEATURE WILL BE THE FOCUS FOR
A REGIONAL SEVERE WEATHER OUTBREAK WHICH WILL ENCOMPASS WEST TEXAS.
THE MAIN CONCERN FOR ORGANIZED AND WIDESPREAD SEVERE CONVECTION
FRIDAY AFTERNOON/EVENING WILL BE INSTABILITY DUE TO CLOUD COVER AND
REMNANTS OF MORNING STORMS. DYNAMICS WILL BE FAVORABLE FOR
LARGE-SCALE ASCENT ACROSS THE ENTIRE AREA...WITH THE BEST LIFT
OCCURRING NORTH AND WEST AND DECREASING IN INTENSITY TO THE SOUTH
AND EAST.
AS HEIGHTS FALL AHEAD OF THIS LOW BY MID AFTERNOON...DISCRETE CELLS
WILL HAVE THE INITIAL CHANCE TO COMMENCE. BACKING LOW-LEVEL WINDS
AND INCREASINGLY CLOCKWISE-CURVED HODOGRAPHS WILL SUPPORT THE CHANCE
FOR AN ISOLATED TORNADO. WHILE A FEW SURFACE-BASED STORMS MAY BE
ABLE TO GENERATE TO THE WEST NEAR THE NEW MEXICO STATE LINE...WHERE
BETTER MIXING WILL TAKE PLACE...A RESIDUAL COOLER AND MORE STABLE
BOUNDARY LAYER WILL LIKELY CAUSE STORMS TO BE ELEVATED IN NATURE.
THIS WILL LEAD TO PRIMARILY A HAIL THREAT AS CONVECTIVE WIND GUSTS
MAY STRUGGLE TO REACH THE SURFACE. HEAVY RAIN WILL ALSO BE A
POSSIBILITY WHERE STORMS TRAIN.
LONG TERM...
CONVECTION IS EXPECTED TO CONTINUE THROUGHOUT THE EVENING AND
OVERNIGHT HOURS FRIDAY INTO SATURDAY. THE MOST WIDESPREAD COVERAGE
IS EXPECTED TO BE BETWEEN 00Z AND 06Z. MAXIMUM LIFT FROM THE CLOSED
LOW/TROUGH CONTINUES TO BE PROGGED NORTH OF THE AREA. THE BEST
THERMODYNAMIC PARAMETERS WILL BE CENTERED OVER THE SOUTHWESTERN
TEXAS PANHANDLE AND VERY IMPRESSIVE FOR OCTOBER STANDARDS. AS CLOUDS
CLEAR OUT...CAPES IN EXCESS OF 1000 J/KG WILL BE SEEN NEAR THE
TEXAS...NEW MEXICO STATE LINE. INSTABILITY WILL BE LESS AND CIN WILL
BE HIGHER EAST OF HERE WITH CLOUD COVER PERSISTING FOR A GOOD
PORTION OF THE DAYTIME. THE BEST LOW LEVEL HELICITY AND SHEAR
VECTORS WILL AGAIN BE LOCATED OVER THE SOUTHWESTERN TEXAS PANHANDLE.
MODEL HODOGRAPHS DO SHOW SOME LOW LEVEL TURNING BUT IS STILL RATHER
WEAK. THOUGH IT IS WEAK...IT IS ENOUGH TO NOT BE IGNORED FOR A
TORNADO THREAT. HOWEVER...ABOVE THIS LOW LAYER...STRONG SHEAR WILL
EXIST LENDING TO ORGANIZED SEVERE CONVECTION. LARGE HAIL IS STILL
THE PRIMARY THREAT FROM THIS CONVECTION. WOULD STILL EXPECT MORE
DISCRETE CELLS OVER THE SOUTHWESTERN PANHANDLE AND SOUTH PLAINS AND
MORE LINEAR FEATURES FARTHER NORTH IN THE WESTERN AND CENTRAL
PANHANDLE. STORM CHANCES WILL SHIFT EAST DURING THE EVENING AND
OVERNIGHT WITH THE DEVELOPMENT OF A LOW LEVEL JET. THIS LLJ WILL BE
MAXIMIZED OVER THE ROLLING PLAINS AT IMPRESSIVE SPEEDS NEAR 50KT.
ELEVATED INSTABILITY WILL ALSO CONTINUE THROUGH THE NIGHT WITH THIS
LLJ.
A CLOSED LOW SOLUTION PERSISTING INTO SATURDAY APPEARS MORE
PLAUSIBLE WITH THE LATEST MODEL RUNS. UPPER LEVEL LIFT FROM THIS LOW
WILL BE TRAILING OVER THE ROLLING PLAINS SATURDAY MORNING AND
AFTERNOON. STORM REDEVELOPMENT WILL BE POSSIBLE OVER THIS AREA
DURING THIS TIME PERIOD. A STRONG UPPER LEVEL JET WILL BE MOVING
DIRECTLY OVERHEAD ON SATURDAY. THIS LIFT MAY OBTAIN SOME ASSISTANCE
FROM A PACIFIC FRONT SWEEPING INTO THE ROLLING PLAINS. THIS FRONT IS
EXPECTED TO SIGNIFICANTLY SLOW OR EVEN STALL OUT BY THE AFTERNOON.
SUBSIDENCE AND DRYING OUT WILL OCCUR ON SATURDAY ACROSS THE REST OF
THE AREA AND THEN THROUGH THE ROLLING PLAINS ON SUNDAY. A COLD FRONT
IS STILL EXPECTED BY LATE TUESDAY OR WEDNESDAY. HOWEVER THE GFS IS
NOTABLY STRONGER WITH THIS FRONT THAN THE ECMWF. JDV
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 58 75 50 73 42 / 50 70 80 0 0
TULIA 58 76 58 75 46 / 40 50 70 0 0
PLAINVIEW 58 77 58 77 47 / 40 50 70 0 0
LEVELLAND 59 78 57 77 48 / 30 60 60 0 0
LUBBOCK 62 78 62 78 48 / 30 50 60 0 0
DENVER CITY 59 80 58 77 49 / 30 60 50 0 0
BROWNFIELD 59 79 59 78 49 / 30 60 60 0 0
CHILDRESS 64 83 66 82 52 / 30 30 60 20 0
SPUR 65 82 64 80 52 / 30 20 60 20 0
ASPERMONT 66 84 68 82 54 / 10 20 50 30 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
51/33
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1246 PM CDT WED OCT 10 2012
.UPDATE...
SEE AVIATION DISCUSSION BELOW.
&&
.AVIATION...
FRONTAL BOUNDARY HAS SAGGED TO NEAR A SAN ANGELO TO BRADY
LINE...WITH IFR CONDITIONS TOUGH TO GET RID OF NORTH OF THE FRONT ACROSS
THE BIG COUNTRY AND THE KABI TERMINAL. CONDITIONS SHOULD IMPROVE
SOMEWHAT DURING THE AFTERNOON...BUT WILL LIKELY STAY AT HIGH END
IFR TO LOW END MVFR THROUGH SUNSET. FARTHER SOUTH...MVFR CIGS HAVE
LIFTED ENOUGH TO REACH LOW EVEN VFR CIGS...AND THESE SHOULD
CONTINUE THROUGH THE AFTERNOON.
LOW LEVEL JET OF 35 TO 40KTS LIFTS PLENTIFUL MOISTURE UP AND OVER
THE FRONTAL BOUNDARY...GENERATING WIDE SPREAD IFR CIGS. WORST
CONDITIONS WILL BE NORTH OF THE FRONT AGAIN...KABI SPECIFICALLY
... WHERE LIFR WILL BE POSSIBLE WITH VERY LOW CIGS AND VSBYS.
&&
.PREV DISCUSSION... /ISSUED 847 AM CDT WED OCT 10 2012/
UPDATE...
QUICK UPDATE ON FORECAST HIGHS THIS AFTERNOON.
DISCUSSION...
COLD ADVECTION CONTINUES TO STRENGTHEN BEHIND A FRONTAL BOUNDARY
THAT HAS MOVED SOUTH OF INTERSTATE 20 THIS MORNING...WITH NORTH
WINDS GUSTING OVER 20 KTS AT TIMES. LATEST RUC AND MESOETA
SUGGESTS THAT WITH CLOUD COVER HOLDING IN PLACE...TEMPERATURES
NORTH OF THE BOUNDARY MAY STRUGGLE TO CLIMB VERY MUCH AT ALL TODAY.
HAVE LOWERED AFTERNOON HIGHS ABOUT 5 DEGREES FOR THOSE AREAS ALONG
AND NORTH OF INTERSTATE 20...WHICH IS STILL AS MUCH AS 10 DEGREES
WARMER THAN SOME OF THE DATA COMING IN WOULD SUGGEST. HOWEVER...
THIS WOULD BE HIGHLY DEPENDENT ON CLOUD COVER NOT BREAKING AT
ALL...SO WILL GET A FEEL ON THAT BEFORE DROPPING READINGS EVEN
MORE.
WILL WATCH THE SOUTHWARD EXTENT OF THE FRONTAL BOUNDARY HERE IN
THE NEXT FEW HOURS BEFORE THE BOUNDARY STALLS...AND FULLY EXPECT
TO SEE ADDITIONAL UPDATES AS WE GET A BETTER HANDLE ON THAT
POSITION AS WELL.
PREV DISCUSSION... /ISSUED 618 AM CDT WED OCT 10 2012/
DISCUSSION...
SEE 12Z AVIATION DISCUSSION BELOW.
AVIATION...
WATCHING AN AREA OF STRATUS MOVING SLOWLY WEST-NORTHWEST ACROSS
THE SOUTHERN HEARTLAND AND NORTHWEST HILL COUNTRY. LOOKS LIKE
MVFR/LOCAL IFR CIGS ACROSS THE SOUTHERN TERMINALS THIS MORNING.
SOME UNCERTAINTY FOR THE KSJT AND THE KABI TERMINALS. ANOTHER
AREA OF LOW CLOUDS DEVELOPING SOUTH ACROSS THE NORTHERN BIG
COUNTRY...AND WILL START KABI WITH MVFR CIGS...THEN RISING TO LOW
END VFR BY 16Z. MAINLY VFR CONDITIONS ARE EXPECTED BY MID
AFTERNOON ACROSS THE AREA...SOME LOW END VFR CIGS REMAINING ACROSS
THE SOUTHERN TERMINALS. LOW LEVEL SOUTHERLY FLOW WILL INCREASE
LATE TONIGHT(850MB JET OF 30 TO 40 KNOTS). EXPECT MVFR CIGS TO
RETURN TO THE TERMINALS AFTER 06Z THU.
21
PREV DISCUSSION... /ISSUED 437 AM CDT WED OCT 10 2012/
SHORT TERM...
COOLER TEMPERATURES AND THE POTENTIAL FOR RAIN HIGHLIGHT THE SHORT
TERM FORECAST. ANOTHER COLD FRONT HAS MOVED TO A POSITION NEAR OUR
INTERSTATE 20 CORRIDOR. BEHIND THE FRONT...SURFACE WINDS ARE NORTH
AT 15 MPH...WITH GUSTS AROUND 20 MPH. SOUTH OF THE FRONT...WINDS
ARE LIGHT AND VARIABLE ACROSS WEST CENTRAL TEXAS. MODELS STALL THE
FRONT NEAR OUR INTERSTATE 10 CORRIDOR THIS AFTERNOON. WITH SOME
SURFACE COLD AIR ADVECTION BEHIND THE FRONT...AFTERNOON HIGHS
ACROSS THE BIG COUNTRY WILL BE MUCH COOLER TODAY...AS COMPARED TO
YESTERDAY...WITH HIGHS MAINLY IN 70 TO 73 RANGE. FARTHER SOUTH
ACROSS WEST CENTRAL TEXAS TODAY...SURFACE COLD AIR ADVECTION WILL
NOT BE AS DOMINATE. THUS...HIGHS ELSEWHERE TODAY WILL BE MAINLY IN
THE 75 TO 80 RANGE. OVERNIGHT TONIGHT...MOIST UPGLIDE OVER THE
COLD AIR AT THE SURFACE WILL CREATE LIGHT RAIN...MAINLY AFTER
MIDNIGHT TONIGHT. I DO NOT EXPECT MUCH IF ANY ACCUMULATIONS. MOIST
UPGLIDE WILL CONTINUE INTO THURSDAY MORNING ACROSS WEST CENTRAL
TEXAS...AS THE FRONT BEGINS TO SLOWLY MOVE BACK NORTH ACROSS OUR
COUNTIES AS A WARM FRONT. SOME BREAKS IN THE LOW CLOUDS THURSDAY
AFTERNOON...ALONG WITH SURFACE WARM AIR ADVECTION...WILL HELP
PRODUCE AFTERNOON HIGHS CLOSER TO SEASONAL NORMALS. DOMINATE
SOUTHERLY LOW LEVEL FLOW WILL HELP MOISTURE RETURN TO THE BOUNDARY
LAYER THURSDAY NIGHT. BY SUNRISE FRIDAY...ANOTHER UPPER LOW WILL
BE MOVING EAST ACROSS SOUTHERN ARIZONA AND SETTING THE STAGE FOR
POSSIBLE SHOWERS AND THUNDERSTORMS ACROSS WEST CENTRAL TEXAS. THE
MAIN DYNAMICS WILL BE NORTH OF OUR AREA. THUS...I BELIEVE THE RISK
FOR SEVERE THUNDERSTORMS WILL BE LOW FRIDAY AND FRIDAY NIGHT.
HOWEVER...IF LATER MODEL RUNS MOVE THE FORECAST TRACK SOUTH...THE
RISK FOR SEVERE THUNDERSTORMS WILL INCREASE ACROSS OUR BIG COUNTRY
COUNTIES FOR FRIDAY AFTERNOON AND EVENING.
HUBER
LONG TERM...
RAIN CHANCES FOR THE LONG TERM STILL LOOK PROMISING. AS THE UPPER
LOW MOVES ACROSS THE CENTRAL ROCKIES FRIDAY NIGHT AND SATURDAY
INTO THE CENTRAL PLAINS...AN ASSOCIATED SURFACE LOW WILL DRAG
ANOTHER FRONTAL BOUNDARY ACROSS WEST CENTRAL TEXAS. THE BEST
CHANCE FOR SHOWERS AND THUNDERSTORMS WILL BE SATURDAY AND SATURDAY
NIGHT...WHEN SURFACE MOISTURE CONVERGENCE ALONG OR NEAR THE FRONT
WILL PEAK. ALSO...THIS FRONT WILL LIKELY STALL ACROSS WEST CENTRAL
SATURDAY NIGHT. THUS...THE POTENTIAL FOR SHOWERS AND
THUNDERSTORMS WILL LINGER INTO SUNDAY. IN ADDITION...SATURDAY AND
SATURDAY NIGHT LOOK TO BE THE BEST PERIODS FOR SEVERE
THUNDERSTORMS...WITH MODEL FORECAST SOUNDINGS INDICATING AN
INVERTED V SOUNDING ACROSS WEST CENTRAL TEXAS BY 18Z ON SATURDAY.
AGAIN...I DO NOT ANTICIPATE WIDESPREAD SEVERE THUNDERSTORMS.
HOWEVER...THE POSSIBILITY IS WORTH AT LEAST A MENTION AT THIS
TIME. FOR THE REMAINDER OF THE LONG TERM...INTO NEXT TUESDAY...DRY
CONDITIONS WILL DOMINATE AS HIGH PRESSURE BUILDS OVER THE REGION.
AS FOR TEMPERATURES...NUMBERS CLOSE TO MOS GUIDANCE LOOK ON
TRACK...WITH AFTERNOON HIGHS IN THE 80S AND OVERNIGHT LOWS IN THE
60S.
HUBER
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 67 60 84 66 82 / 10 10 10 10 10
SAN ANGELO 73 65 84 68 83 / 5 10 10 10 10
JUNCTION 80 68 85 70 82 / 5 10 10 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
847 AM CDT WED OCT 10 2012
.UPDATE...
QUICK UPDATE ON FORECAST HIGHS THIS AFTERNOON.
&&
.DISCUSSION...
COLD ADVECTION CONTINUES TO STRENGTHEN BEHIND A FRONTAL BOUNDARY
THAT HAS MOVED SOUTH OF INTERSTATE 20 THIS MORNING...WITH NORTH
WINDS GUSTING OVER 20 KTS AT TIMES. LATEST RUC AND MESOETA
SUGGESTS THAT WITH CLOUD COVER HOLDING IN PLACE...TEMPERATURES
NORTH OF THE BOUNDARY MAY STRUGGLE TO CLIMB VERY MUCH AT ALL TODAY.
HAVE LOWERED AFTERNOON HIGHS ABOUT 5 DEGREES FOR THOSE AREAS ALONG
AND NORTH OF INTERSTATE 20...WHICH IS STILL AS MUCH AS 10 DEGREES
WARMER THAN SOME OF THE DATA COMING IN WOULD SUGGEST. HOWEVER...
THIS WOULD BE HIGHLY DEPENDENT ON CLOUD COVER NOT BREAKING AT
ALL...SO WILL GET A FEEL ON THAT BEFORE DROPPING READINGS EVEN
MORE.
WILL WATCH THE SOUTHWARD EXTENT OF THE FRONTAL BOUNDARY HERE IN
THE NEXT FEW HOURS BEFORE THE BOUNDARY STALLS...AND FULLY EXPECT
TO SEE ADDITIONAL UPDATES AS WE GET A BETTER HANDLE ON THAT
POSITION AS WELL.
&&
.PREV DISCUSSION... /ISSUED 618 AM CDT WED OCT 10 2012/
DISCUSSION...
SEE 12Z AVIATION DISCUSSION BELOW.
AVIATION...
WATCHING AN AREA OF STRATUS MOVING SLOWLY WEST-NORTHWEST ACROSS
THE SOUTHERN HEARTLAND AND NORTHWEST HILL COUNTRY. LOOKS LIKE
MVFR/LOCAL IFR CIGS ACROSS THE SOUTHERN TERMINALS THIS MORNING.
SOME UNCERTAINTY FOR THE KSJT AND THE KABI TERMINALS. ANOTHER
AREA OF LOW CLOUDS DEVELOPING SOUTH ACROSS THE NORTHERN BIG
COUNTRY...AND WILL START KABI WITH MVFR CIGS...THEN RISING TO LOW
END VFR BY 16Z. MAINLY VFR CONDITIONS ARE EXPECTED BY MID
AFTERNOON ACROSS THE AREA...SOME LOW END VFR CIGS REMAINING ACROSS
THE SOUTHERN TERMINALS. LOW LEVEL SOUTHERLY FLOW WILL INCREASE
LATE TONIGHT(850MB JET OF 30 TO 40 KNOTS). EXPECT MVFR CIGS TO
RETURN TO THE TERMINALS AFTER 06Z THU.
21
PREV DISCUSSION... /ISSUED 437 AM CDT WED OCT 10 2012/
SHORT TERM...
COOLER TEMPERATURES AND THE POTENTIAL FOR RAIN HIGHLIGHT THE SHORT
TERM FORECAST. ANOTHER COLD FRONT HAS MOVED TO A POSITION NEAR OUR
INTERSTATE 20 CORRIDOR. BEHIND THE FRONT...SURFACE WINDS ARE NORTH
AT 15 MPH...WITH GUSTS AROUND 20 MPH. SOUTH OF THE FRONT...WINDS
ARE LIGHT AND VARIABLE ACROSS WEST CENTRAL TEXAS. MODELS STALL THE
FRONT NEAR OUR INTERSTATE 10 CORRIDOR THIS AFTERNOON. WITH SOME
SURFACE COLD AIR ADVECTION BEHIND THE FRONT...AFTERNOON HIGHS
ACROSS THE BIG COUNTRY WILL BE MUCH COOLER TODAY...AS COMPARED TO
YESTERDAY...WITH HIGHS MAINLY IN 70 TO 73 RANGE. FARTHER SOUTH
ACROSS WEST CENTRAL TEXAS TODAY...SURFACE COLD AIR ADVECTION WILL
NOT BE AS DOMINATE. THUS...HIGHS ELSEWHERE TODAY WILL BE MAINLY IN
THE 75 TO 80 RANGE. OVERNIGHT TONIGHT...MOIST UPGLIDE OVER THE
COLD AIR AT THE SURFACE WILL CREATE LIGHT RAIN...MAINLY AFTER
MIDNIGHT TONIGHT. I DO NOT EXPECT MUCH IF ANY ACCUMULATIONS. MOIST
UPGLIDE WILL CONTINUE INTO THURSDAY MORNING ACROSS WEST CENTRAL
TEXAS...AS THE FRONT BEGINS TO SLOWLY MOVE BACK NORTH ACROSS OUR
COUNTIES AS A WARM FRONT. SOME BREAKS IN THE LOW CLOUDS THURSDAY
AFTERNOON...ALONG WITH SURFACE WARM AIR ADVECTION...WILL HELP
PRODUCE AFTERNOON HIGHS CLOSER TO SEASONAL NORMALS. DOMINATE
SOUTHERLY LOW LEVEL FLOW WILL HELP MOISTURE RETURN TO THE BOUNDARY
LAYER THURSDAY NIGHT. BY SUNRISE FRIDAY...ANOTHER UPPER LOW WILL
BE MOVING EAST ACROSS SOUTHERN ARIZONA AND SETTING THE STAGE FOR
POSSIBLE SHOWERS AND THUNDERSTORMS ACROSS WEST CENTRAL TEXAS. THE
MAIN DYNAMICS WILL BE NORTH OF OUR AREA. THUS...I BELIEVE THE RISK
FOR SEVERE THUNDERSTORMS WILL BE LOW FRIDAY AND FRIDAY NIGHT.
HOWEVER...IF LATER MODEL RUNS MOVE THE FORECAST TRACK SOUTH...THE
RISK FOR SEVERE THUNDERSTORMS WILL INCREASE ACROSS OUR BIG COUNTRY
COUNTIES FOR FRIDAY AFTERNOON AND EVENING.
HUBER
LONG TERM...
RAIN CHANCES FOR THE LONG TERM STILL LOOK PROMISING. AS THE UPPER
LOW MOVES ACROSS THE CENTRAL ROCKIES FRIDAY NIGHT AND SATURDAY
INTO THE CENTRAL PLAINS...AN ASSOCIATED SURFACE LOW WILL DRAG
ANOTHER FRONTAL BOUNDARY ACROSS WEST CENTRAL TEXAS. THE BEST
CHANCE FOR SHOWERS AND THUNDERSTORMS WILL BE SATURDAY AND SATURDAY
NIGHT...WHEN SURFACE MOISTURE CONVERGENCE ALONG OR NEAR THE FRONT
WILL PEAK. ALSO...THIS FRONT WILL LIKELY STALL ACROSS WEST CENTRAL
SATURDAY NIGHT. THUS...THE POTENTIAL FOR SHOWERS AND
THUNDERSTORMS WILL LINGER INTO SUNDAY. IN ADDITION...SATURDAY AND
SATURDAY NIGHT LOOK TO BE THE BEST PERIODS FOR SEVERE
THUNDERSTORMS...WITH MODEL FORECAST SOUNDINGS INDICATING AN
INVERTED V SOUNDING ACROSS WEST CENTRAL TEXAS BY 18Z ON SATURDAY.
AGAIN...I DO NOT ANTICIPATE WIDESPREAD SEVERE THUNDERSTORMS.
HOWEVER...THE POSSIBILITY IS WORTH AT LEAST A MENTION AT THIS
TIME. FOR THE REMAINDER OF THE LONG TERM...INTO NEXT TUESDAY...DRY
CONDITIONS WILL DOMINATE AS HIGH PRESSURE BUILDS OVER THE REGION.
AS FOR TEMPERATURES...NUMBERS CLOSE TO MOS GUIDANCE LOOK ON
TRACK...WITH AFTERNOON HIGHS IN THE 80S AND OVERNIGHT LOWS IN THE
60S.
HUBER
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 68 62 83 66 82 / 5 10 20 10 20
SAN ANGELO 76 65 82 68 83 / 5 20 20 10 20
JUNCTION 80 69 80 70 82 / 5 20 20 10 20
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1025 PM CDT THU OCT 11 2012
.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
345 PM CDT THU OCT 11 2012
AT 3 PM...RADAR CONTINUES TO SHOW A BAND OF RAIN SHOWERS ACROSS
SOUTH CENTRAL AND SOUTHEAST MINNESOTA...NORTHERN IOWA...AND
SOUTHERN WISCONSIN. THERE WAS EVEN A REPORT OF A MIX OF RAIN AND
SLEET 7 MILES WEST OF CRESCO IN HOWARD COUNTY. THE KARX
CORRELATION COEFFICIENTS SHOW VALUES AS LOW 0.8 COLLOCATED WITH
THE HIGHEST REFLECTIVITIES...SO WOULD NOT BE SURPRISED THAT THERE
WILL BE OTHER REPORTS THIS AFTERNOON. THIS PRECIPITATION IS
ASSOCIATED WITH MODERATE TO STRONG 900-700 MB FRONTOGENESIS. THE
LATEST RAP CONTINUES TO SHOW THAT THIS FORCING WILL CONTINUE
TO MOVE SOUTH THIS AFTERNOON...AND BY 11.00Z IT SHOULD BE LOCATED
JUST SOUTH OF THE FORECAST AREA.
LIKE THE PAST SEVERAL DAYS...THE 11.12Z MODELS CONTINUE TO SHOW
THAT A CANADIAN HIGH PRESSURE SYSTEM WILL BUILD SOUTH INTO THE
UPPER MISSISSIPPI RIVER VALLEY TONIGHT...AND THEN MOVE QUICKLY
EAST THROUGH THE OHIO RIVER VALLEY AND INTO THE MID ATLANTIC ON
FRIDAY. WITH LIGHT WINDS...MAINLY CLEAR SKIES...AND LIGHT WINDS
OVERNIGHT...TEMPERATURES WILL FALL INTO THE 20S IN MOST LOCATIONS.
THERE MAY BE EVEN A FEW TEENS IN CENTRAL AND NORTH CENTRAL
WISCONSIN.
ON FRIDAY NIGHT...A SHORT WAVE TROUGH WILL EJECT OUT AHEAD OF A
CLOSED LOW PRESSURE SYSTEM OVER COLORADO. MODERATE TO STRONG
ISENTROPIC LIFT WILL DEVELOP AHEAD OF THIS WAVE. IN
ADDITION...THERE WILL BE STRONG 925 AND 850 MB MOISTURE TRANSPORT
INTO THE REGION. THE NAM QUICKLY GENERATES PRECIPITATION ON FRIDAY
EVENING. MEANWHILE THE OTHER MODELS SUGGEST THAT THE PRECIPITATION
WILL NOT DEVELOP UNTIL AFTER MIDNIGHT FRIDAY NIGHT. LOOKING AT THE
BUFKIT MODEL SOUNDINGS THERE IS VERY LITTLE DIFFERENCE BETWEEN THE
GFS AND NAM. BOTH MODELS SHOW THAT DURING THE EVENING THE AIR MASS
WILL MOISTEN RAPIDLY BETWEEN 800 AND 600 MB AND THERE IS SOME
MODERATE OMEGA IN THIS SAME LAYER. DESPITE THE NAM/WRF APPEARING
AS AN OUTLIER DECIDED THAT IT HAD A MUCH BETTER HANDLE OF THE
DEVELOPMENT OF INITIAL SHOWERS THAN THE OTHER MODELS. AFTER
MIDNIGHT...THE 0-3 KM MOST UNSTABLE CAPES CLIMB UP TO 1000 J/KG
MAINLY SOUTH OF THE INTERSTATE 94 CORRIDOR. AS A RESULT...WENT
WITH THE BEST CHANCES FOR THUNDERSTORMS IN THIS AREA. WITH 1-7 KM
SHEAR LESS THAN 25 KNOTS...NOT ANTICIPATING ANY OF THESE
THUNDERSTORMS TO BECOME SEVERE.
ON SATURDAY MORNING...THERE ARE SOME MODELS SUGGEST THAT THE BEST
MOISTURE TRANSPORT WILL MOVE EAST OF THE AREA BY LATE MORNING. AS
A RESULT STILL THINKING THAT THERE WILL BE A POSSIBILITY OF A
BREAK IN THE SHOWERS AND THUNDERSTORMS LATE SATURDAY MORNING AND
EARLY AFTERNOON. THE MAIN QUESTION FOR THE AFTERNOON WILL THERE BE
SOME CLEARING IN THE WARM SECTOR OF THIS SYSTEM TO HELP INCREASE
THE MEAN LAYER CAPES ALONG AND SOUTH OF THE INTERSTATE 90
CORRIDOR. BOTH THE GFS AND NAM CONTINUE TO HINT THAT THIS WILL
MORE LIKELY OCCUR ACROSS EASTERN IOWA...ILLINOIS...AND THE
SOUTHERN QUARTER OF WISCONSIN. HOWEVER THE 10.09Z SUGGEST THAT THE
MLCAPE WILL BE GREATER THAN 500 J/KG...THE 0-1 KM HELICITY WILL BE
GREATER THAN 100...AND BOTH THE 0-3 KM AND 0-6 KM SHEAR WILL BE
FAVORABLE FOR THE POSSIBILITY OF SEVERE WEATHER ALONG THE COLD
FRONT LATE SATURDAY AFTERNOON AND EVENING ALONG AND SOUTH OF THE
INTERSTATE 90 CORRIDOR.
.LONG TERM...SUNDAY THROUGH THURSDAY
345 PM CDT THU OCT 11 2012
ON SUNDAY MORNING...THE MODELS CONTINUE TO SHOW THAT THE
DEFORMATION BAND ON THE BACK SIDE OF THE LOW PRESSURE SYSTEM WILL
STILL LINGER ACROSS MUCH OF THE AREA. AS A RESULT...RAISED THE
PRECIPITATION CHANCES A BIT MORE.
BEYOND THIS TIME PERIOD...THE MODELS CONTINUE TO STRUGGLE ON THE
TIMING OF SYSTEMS AND THE UPPER FLOW. WITH THIS SAID...THERE
CONTINUES TO BE A SIGNAL FOR A STRONG LOW PRESSURE SYSTEM TO
MOVE THROUGH THE REGION ON WEDNESDAY. THIS SYSTEM IS EXPECTED TO
CARVE OUT A BROAD TROUGH ACROSS THE EASTERN CONUS WHICH WILL
RETURN COLDER AIR TO THE REGION.
&&
.AVIATION...
1025 PM CDT THU OCT 11 2012
HIGH PRESSURE BUILDS IN FROM THE NORTHERN PLAINS OVERNIGHT...WITH
THE HIGH OVERHEAD BY 12Z FRI. CLEAR SKIES WITH A LIGHT WIND WILL
RESULT. IT WOULD BE A GREAT SETUP FOR RIVER VALLEY FOG...EXCEPT THE
T/TD SPREAD IS LARGE /25 DEGREES AT 02Z/ AND WILL LIKELY REMAIN THAT
WAY OVERNIGHT. IN ADDITION...DRIER AIR IS ADVECTING IN FROM THE
NORTHWEST. SO...DON/T EXPECT A FG IMPACT AT KLSE FRI MORNING.
THE HIGH WILL EXIT QUICKLY EAST ON FRI...WITH THE WINDS GRADUALLY
SHIFTING TO THE SOUTH AND INCREASING LATER IN THE DAY. CLOUDS WILL
BE ON THE INCREASE FRIDAY NIGHT AS LOW LEVEL THERMODYNAMICS AND
INCREASING SATURATION PUSH IN FROM THE SOUTH/SOUTHWEST...AHEAD OF A
LOW PRESSURE SYSTEM/COLD FRONT APPROACHING FROM THE WEST. AREAS OF
-SHRA WILL LIKELY DEVELOP FROM THE FORCING OVERNIGHT FRI...WITH SAT
LOOKING LIKE A WET DAY. ENOUGH FORCING AND INSTABILITY THAT A FEW
THUNDERSTORMS WILL BE POSSIBLE. EXPECT CIGS TO DROP INTO THE MVFR
RANGE AROUND 12Z SAT OR SHORTLY AFTER...WITH SOME VSBY RESTRICTIONS
IN THE RAIN.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
345 PM CDT THU OCT 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM....BOYNE
AVIATION.....RIECK
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
915 PM PDT THU OCT 11 2012
.UPDATE...
BAND IS FORMING OVER CENTRAL NEVADA AND IS NOW MOVING WEST. NEW
NAM/GFS IN GOOD AGREEMENT HITTING CHURCHILL COUNTY HARD AND
WESTWARD INTO DOUGLAS COUNTY BY 12Z. LATEST HRRR REALLY DOES NOT
HAVE A SECOND BAND, BUT GIVEN THE CONSISTENCY OF THE GFS/NAM WILL
GO IN THEIR DIRECTION. HAVE INCREASED COVERAGE AGAIN FOR THE
OVERNIGHT HOURS SOUTH OF I-80 HITTING THE HWY 50 CORRIDOR HARDEST
WITH THE SECOND BAND. NOT SURE ABOUT THE AMOUNTS FROM THE NAM/GFS
SHOWING UP TO 1/2 INCH, BUT AMOUNTS OF A TENTH TO QUARTER INCH IN
THE BAND LOOK REASONABLE. ALSO INCREASED CLOUD COVER FOR THE
REMAINDER OF THE NIGHT FOR MOST AREAS.
ALSO MADE SOME SMALL CHANGES TO FRIDAY MORNING AS THE BAND
DISSIPATES. INCREASED COVERAGE FROM FERNLEY SOUTH-SOUTHWESTWARD TO
MARKLEEVILLE AND COLEVILLE. MODELS HOLD ONTO THE BAND UNTIL ALMOST
18Z AS IT WEAKENS. SNOW LEVELS REMAIN HIGH AND 8500 TO 9500 FEET
SO ONLY THE HIGHEST PEAKS WILL SEE ANY SNOW.
&&
.PREVIOUS DISCUSSION... /ISSUED 624 PM PDT THU OCT 11 2012/
UPDATE...
LARGE BAND OF SHOWERS AND ISOLATED THUNDERSTORMS IS NOW MOVING
INTO MINERAL COUNTY AND SOON INTO MONO COUNTY. HRRR SEEMS TO BE
HANDLING THIS FAIRLY WELL RIGHT NOW AND LIKE ITS IDEAS OF
WIDESPREAD SHOWERS THIS EVENING DOWN THERE. HAVE UPDATED TO
INCREASE POPS AND SHOWER COVERAGE FOR MOST OF MONO AND MINERAL
COUNTIES. ALSO BOOSTED QPF A BIT AVERAGE AMOUNTS LIKELY TO BE A
TENTH TO QUARTER INCH.
FURTHER NORTH, SOME SHOWERS ARE MOVING INTO EASTERN CHURCHILL AND
PERSHING COUNTIES AND APPEAR TO BE MORE SCATTERED AT THIS TIME.
WILL CONTINUE TO MONITOR CENTRAL NV DEVELOPMENT THIS EVENING AS A
SECOND BAND IS FORECAST TO DEVELOP FOR PORTIONS OF WEST CENTRAL
NEVADA. EXPECT TO BE UPDATING AGAIN WHEN THE HARDEST HIT AREAS
BECOME CLEARER. MOST LIKELY IT IS LOOKING LIKE THE LOVELOCK-
FERNLEY-MINDEN AREAS TO GET THE BRUNT OF IT RIGHT NOW. COULD SEE A
QUARTER INCH OF RAIN IN THIS SECOND BAND WITH LOCALLY HIGHER
AMOUNTS. WALLMANN
PREVIOUS DISCUSSION... /ISSUED 246 PM PDT THU OCT 11 2012/
SHORT TERM...
UPPER LOW OVER SOCAL TODAY CONTINUES TO SLING ANOMALOUS AMOUNTS
OF MOISTURE UP INTO NV, WITH GEFS PRECIP WATER ANOMALIES 3-4
STANDARD DEVIATIONS ABOVE NORMAL. DEFORMATION ZONE HELPED PRODUCE
WIDESPREAD AREA OF SHOWERS SOUTH OF HWY 50 EARLIER TODAY WITH
SNOW DOWN TO ~7 KFT FROM TIME TO TIME NEAR MAMMOTH. RECENT HRRR
HIGH RESOLUTION RUNS SHOW SHOWER ACTIVITY CONTINUING THIS EVENING
MAINLY SOUTH OF HWY 50, WITH EVEN SOME TSTM POTENTIAL. WILL
FOLLOW THIS GUIDANCE AND ALSO KEEP CHC OF SHOWERS INTO RENO/GREAT
BASIN AREAS BASED ON UPSTREAM RADAR TRENDS OVER CENTRAL NV.
PRIMARY CHALLENGE IS FOR LATE TONIGHT AND TOMORROW, AS ALL MODELS
DEVELOP A ROUGHLY N-S ORIENTED FRONTOGENETIC BAND OF PRECIP OVER
THE FORECAST AREA BUT POSITION IT IN A VARIETY OF LOCATIONS.
SHOULD NAM/SREF VERIFY THEN RENO/CARSON AREAS COULD GET A BURST OF
APPRECIABLE RAIN (SREF HAS 15-25% CHC OF 0.25" 6-12Z TONIGHT),
WHILE GFS/EC IS FURTHER EAST OVER GREAT BASIN. HAVE ATTEMPTED TO
INCORPORATE BOTH THESE POSSIBILITIES SINCE I HAVE NO REASON TO
FAVOR ONE OVER THE OTHER AT THIS TIME. SO FORECAST CONFIDENCE IS
SOMEWHAT LOW TO MODERATE FOR THIS PERIOD.
LOW EXPECTED TO TRANSLATE EASTWARD LATE FRI, WITH SHORTWAVE
RIDGING BUILDING IN OVER THE AREA SAT/SUN WITH WARMING TEMPS.
IMPRESSIVE 185KT JET AND ATMOSPHERIC RIVER EXPECTED TO CRASH
ONSHORE INTO THE PAC NW STARTING SUN/MON. MODELS HAVE TRENDED
DRIER FOR NE CA AND NW NV SO HAVE BACKED DOWN ON SHOWERS THERE,
BUT WITH PROXIMITY TO ACTIVE JET A FEW LIGHT SHOWERS CANNOT BE
RULED OUT SUN NIGHT.
CS
LONG TERM...MONDAY THROUGH THURSDAY...
SHORTWAVE AND PACIFIC JET MOVING ACROSS THE NORTHWEST US ON
MONDAY WILL KEEP NEARLY ALL PRECIP NORTH OF THE OREGON BORDER,
EXCEPT FOR A FEW LIGHT RAIN SHOWERS POSSIBLE IN FAR NORTHWEST NV
AND THE SURPRISE VALLEY. OTHERWISE, DRY CONDITIONS WILL PREVAIL
WITH SOME INCREASE IN WEST WINDS MONDAY AFTERNOON-EVENING AS THE
SHORTWAVE BRUSHES ACROSS NORTHERN NV. FOR THE REMAINDER OF NEXT
WEEK, MEDIUM RANGE GUIDANCE IS IN GOOD AGREEMENT WITH REBUILDING
FLAT RIDGE OVER CA-NV, KEEPING THE REGION DRY WITH LIGHTER WINDS
AND LESS CLOUD COVERAGE. MAX TEMPS FOR MON-THURS WILL BE ABOUT
5-10 DEGREES ABOVE NORMAL, WITH MID 70S TO NEAR 80 DEGREES IN
WESTERN NV AND MID-UPPER 60S IN THE TAHOE BASIN. MJD
AVIATION...
FOR KRNO-KTVL-KTRK, VFR CONDS WITH WIDESPREAD CIGS OF 4000-8000
FT AGL ARE EXPECTED THRU 06Z THIS EVE WITH ISOLD BANDS OF LIGHT
RAIN AND SHOWERS THIS EVE PRODUCING BRIEF MVFR CIGS. A LARGER BAND
OF STEADY MODERATE RAIN IS POSSIBLE LATE TONIGHT THRU FRI MORNING.
THE LOCATION OF THIS BAND REMAINS UNCERTAIN BUT IS MOST LIKELY TO
AFFECT WEST CENTRAL NV. SOME GUIDANCE DATA DOES EXTEND THIS BAND
WEST INTO KRNO AND THE TAHOE BASIN SO WILL KEEP SOME PROB30/TEMPO
MENTION FOR A FEW HOURS AROUND 12Z.
FOR KMMH, ADDITIONAL WRAP AROUND RAIN BANDS ARE POSSIBLE THIS
EVENING AND AGAIN ON FRIDAY PRODUCING MVFR CIGS AT TIMES, BUT SNOW
IS UNLIKELY DURING THE OPERATIONAL HOURS AT KMMH THIS EVENING AND
FRIDAY. MJD
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
513 AM EDT FRI OCT 12 2012
.UPDATE...
MCS TRACKING SOUTHEASTWARD ACROSS CENTRAL TN SHOULD BEGIN TO
INFLUENCE NORTHERN GEORGIA FROM THE NW AS EARLY AS 11Z. SCATTERED
THUNDERSTORM DEVELOPMENT HAS BEEN PERSISTENT OVERNIGHT AND BASED
ON RAP ANALYSIS OF MUCAPE...COMPLEX HAS BEEN RIDING ALONG AN
ELEVATED INSTABILITY AXIS. IT IS STILL EXPECTED TO BECOME LESS
ORGANIZED AND DISSIPATE MOSTLY AFTER 15Z...THOUGH HAVE INCLUDED
ISOLATED TO SCATTERED THUNDER ACROSS PARTS OF THE NORTH. BEST
CHANCE FOR ANY THUNDERSTORMS SHOULD STAY NORTH OF ATLANTA AND
EVENTUALLY BECOME MORE ISOLATED IN COVERAGE INTO MID MORNING. THE
MAIN THREATS WITH ANY THUNDERSTORM WILL BE OCCASIONAL
LIGHTNING...GUSTY WINDS...AND HEAVY RAINFALL. PREVIOUS DISCUSSION
FOLLOWS...
BAKER
&&
.PREV DISCUSSION... /ISSUED 420 AM EDT FRI OCT 12 2012/
.SHORT TERM /TODAY THROUGH SATURDAY/...
CLOUD DECK AND VERY ISOLATED SHOWER DEVELOPMENT ADVECTING INTO
NORTHERN GEORGIA EARLY THIS MORNING HAS LIMITED RADIATIONAL COOLING
SO HAVE THUS RAISED MIN TEMPS BY A FEW DEGREES. MCS CURRENTLY ACROSS
WESTERN KY AND FAR NORTHWESTERN TN IS TRACKING SOUTHEASTWARD IN
ASSOCIATION WITH SOUTHERN EXTENT OF LOW AMPLITUDE UPPER SHORTWAVE
TROUGH. THERE IS A SLIM CHANCE THAT SOME ISOLATED THUNDER COULD
REACH INTO THE FAR NORTHEASTERN PORTION OF THE AREA SHORTLY BEFORE
12Z WITH THE MCS REMNANTS...HOWEVER PROGGED MUCAPE STAYS LOW AND RAP
ANALYSIS HAS COMPLEX TRACKING INTO A MORE STABLE ENVIRONMENT SO WILL
LEAVE CHANCE POPS FOR SHOWERS THROUGH MORNING. HOWEVER...WILL
CLOSELY MONITOR PROGRESSION OF THIS SYSTEM AND UPDATE AS SEEN FIT.
SUITE OF SHORT RANGE MODEL SOLUTIONS GENERALLY AGREE WITH PRECIP
ACROSS NW GEORGIA MAINLY FROM 10-15Z...THOUGH LOOKS TO BE LIMITED IN
COVERAGE AND GREATLY TAPERS OFF INTO THE AFTERNOON AS THE BEST UPPER
LEVEL DYNAMICS STAY REMOVED FROM THE MOISTURE AND WELL NORTH OF THE
REGION. WILL THEREFORE CARRY CHANCE POPS INITIALLY NW TO SLIGHT POPS
BY AFTERNOON AND FURTHER SOUTH INTO WESTERN CENTRAL GEORGIA.
INSTABILITY CONTINUES TO BE LIMITED SO WILL STILL ONLY HAVE SHOWER
POTENTIAL THROUGH AFTERNOON.
CLASSIC CAD EVENT SETS UP FOR SATURDAY WITH 1033-MB PARENT SFC HIGH
PROGGED TO BE CENTERED OVER NEW ENGLAND/MID ATLANTIC REGION BY 12Z.
RESULTANT WEDGE SHOULD LIMIT MAX TEMPS FROM NEAR 70 DEGREES IN THE
NORTHEAST PORTION TO NEAR 80 IN THE SOUTH. GENERALLY A BLEND OF
BIASED CORRECTED MET AND MAV GUIDANCE LOOKED REASONABLE FOR PROGGED
TEMPS THROUGH PERIOD.
BAKER
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
EXTENDED PERIOD BEGINS WITH A SHORTWAVE MOVING THROUGH THE
MISSOURI VALLEY NORTHEAST INTO THE OHIO VALLEY. TRAILING RESIDUAL
ENERGY WILL PUSH INTO THE AREA SUNDAY NIGHT INTO MONDAY WITH A
BROKEN LINE OF SHOWERS AND EMBEDDED THUNDERSTORMS THE RESULT.
INSTABILITY SUFFICIENT FOR STORM DEVELOPMENT BUT MOST SIGNIFICANT
SHEAR LIFTS NORTH OF THE AREA SO EXPECTING NOTHING SIGNIFICANT
LOCALLY AT THIS POINT. HIGH PRESSURE WILL THEN BUILD IN BEHIND THE
FRONT BUT LARGELY ZONAL FLOW WILL KEEP TEMPS ELEVATED THROUGH MID WEEK.
EXTENDED GUIDANCE COMING INTO BETTER AGREEMENT WRT NEXT MAJOR
SYSTEM SLATED FOR THU. MAIN LOW TO LIFT WELL NORTH OVER THE GREAT
LAKES REGION BUT UPPER TROUGH EXTENDS WELL INTO THE GULF AND WITH
A SPLIT FLOW PATTERN AT THE JET STREAM LEVEL...MODELS HAVE NO
TROUBLE GENERATING PRECIP AREAWIDE. WILL HOLD AT HIGH END CHANCE
FOR NOW THIS FAR OUT AND THE FACT THAT THIS IS THE FIRST RUN
MODELS HAVE SHOWN THIS TYPE OF CONSENSUS.
DEESE
&&
.AVIATION...
06Z UPDATE... VFR CONDITIONS EXPECTED THROUGH PERIOD.
CIGS SHOULD GRADUALLY INCREASE IN COVERAGE AND LOWER TO NEAR
BKN040 EARLY THIS MORNING FROM NORTH TO SOUTH AND PERSIST INTO
MIDDAY FRIDAY. AFTER 18Z MOST SITES SHOULD TRANSITION TO AROUND
SCT040 AND BKN150...THEN REDUCE SOME IN COVERAGE BY EVENING. CALM
WINDS INITIALLY SHOULD BECOME NW BY 14Z AND AROUND 10KTS OR LESS
WITH SLIGHTLY HIGHER AT KATL BY EARLY AFTERNOON. LOOK TO SEE A
SHIFT TO NE WINDS NEAR 06Z SATURDAY CLOSER TO END OF FORECAST
PERIOD. THERE IS A SLIGHT CHANCE FOR SOME SHOWERS DURING THE
DAYTIME HOURS...HOWEVER GREATEST CHANCE SHOULD STAY NW OF TAF
SITES...THEREFORE DID NOT INCLUDE MENTION.
//ATL CONFIDENCE...06Z UPDATE...
HIGH CONFIDENCE ALL ELEMENTS.
BAKER
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 78 55 72 46 / 20 10 5 0
ATLANTA 79 57 74 52 / 20 10 5 10
BLAIRSVILLE 69 49 68 45 / 30 5 5 5
CARTERSVILLE 77 53 75 48 / 30 10 5 10
COLUMBUS 85 63 80 56 / 20 20 5 10
GAINESVILLE 74 56 70 49 / 30 5 5 10
MACON 83 59 80 49 / 10 10 5 0
ROME 76 54 77 48 / 30 10 5 10
PEACHTREE CITY 79 58 75 48 / 20 20 5 10
VIDALIA 84 63 79 55 / 5 5 5 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BAKER
LONG TERM....DEESE
AVIATION...BAKER
AREA FORECAST DISCUSSION...CORRECTION
NWS LINCOLN IL
330 AM CDT FRI OCT 12 2012
.DISCUSSION...
ISSUED 330 AM CDT FRI OCT 12 2012
SHORT TERM...TODAY THROUGH SUNDAY NIGHT
A FRONTAL BOUNDARY FROM CENTRAL INDIANA INTO SE IL JUST SE OF I-70
AND INTO SOUTHERN MO TO CONTINUE PRESSING SOUTHWARD THROUGH
SOUTHERN IL THIS MORNING AND KEEPING ITS CHANCES OF SHOWERS SOUTH
OF CENTRAL/SE IL. HAD A FEW SPRINKLES EARLIER TONIGHT IN PARTS OF
CENTRAL IL WITH A FEW LIGHT RAIN SHOWERS IN FAR SE IL AND THATS
ABOUT IT. 1032 MB HIGH PRESSURE OVER MN TO DRIFT EAST TOWARD LAKE MI
BY 18Z/1 PM TODAY AND TO LAKE ERIE BY 00Z/7 PM EARLY THIS EVENING.
SOME PATCHES OF MID LEVEL CLOUDS OVER SE IL AND THE IL RIVER
VALLEY TO DECREASE DURING THE MORNING GIVING WAY TO PARTLY TO
MOSTLY SUNNY SKIES TODAY. HIGHS TO BE IN THE UPPER 50S AND LOWER
60S WITH COOLEST READINGS FROM I-74 NORTH...THOUGH NEAR 65 BY
LAWRENCEVILLE.
STRONG 560 DM 500 MB LOW OVER SOUTHERN CA TO EJECT NE INTO THE
CENTRAL PLAINS BY MIDNIGHT SAT NIGHT AND TO LAKE MI BY SUNDAY
AFTERNOON. SURFACE LOW TO DEVELOP OVER EASTERN CO BY MIDNIGHT
TONIGHT AND MOVE INTO THE CENTRAL PLAINS BY MIDNIGHT SAT NIGHT
AND LIFT NE INTO THE WESTERN GREAT LAKES BY 18Z/1 PM SUNDAY.
MODELS CONTINUE SLOWER TREND WITH THIS STRONG STORM SYSTEM AND
SPC CONTINUES SLIGHT RISK OF SEVERE STORMS FROM I-55 NW OVERNIGHT
SAT NIGHT FOR MAINLY DAMAGING WIND GUSTS. STRONG WINDS AIDED BY
50-60KT LOW LEVEL JET AND DEEP MOISTURE AND STRONG WIND SHEAR.
CONTINUED HIGH POPS OVER NORTHERN/NW COUNTIES LATER FRI NIGHT AND
SAT WHILE AREAS SOUTH OF I-72 MAINLY DRY WITH SLIGHT CHANCE OF
CONVECTION AT BEST WHILE SE IL LIKELY REMAINS DRY UNTIL LATER
SAT NIGHT. BEST CHANCES OF CONVECTION WILL BE SAT NIGHT...THOUGH NOT
GETTING INTO SE IL UNTIL LATER SAT NIGHT INTO SUNDAY MORNING. SPC
ALSO HAS SLIGHT RISK OF SEVERE STORMS SE OF DECATUR SUNDAY FOR
MAINLY HAIL PER DAY3 OUTLOOK WHILE POSSIBLE SQUALL LINE SUNDAY WILL
BE EAST OF IL OVER INDIANA. MUCH WARMER HIGHS OF 75-80F SAT AND MORE
HUMID WITH MILDER LOWS 60-65F SAT NIGHT. HIGHS SUNDAY RANGE FROM
UPPER 60S NW OF THE IL RIVER TO THE UPPER 70S TO NEAR 80F IN FAR SE
IL BY LAWRENCEVILLE.
LONG TERM...MONDAY THROUGH FRIDAY
QUIET WEATHER EXPECTED MONDAY THROUGH TUESDAY WITH WEAK SURFACE
HIGH PRESSURE RIDGE BUILDING INTO AREA MONDAY AS UPPER LEVEL TROF
SHIFTS EAST OF IL...AND UPPER LEVEL RIDGE MOVING INTO IL TUE.
DEEPENING LOW PRESSURE BELOW 1000 MB MOVING EAST ACROSS THE
NORTHERN PLAINS TO NEAR NORTHERN LAKE SUPERIOR BY SUNRISE WED TO
SWING A COLD FRONT SE TOWARD NW IL. THIS TO SPREAD CHANCE OF
SHOWERS AND ISOLATED THUNDERSTORMS INTO CENTRAL IL TUE NIGHT AND
INTO CENTRAL AND SE IL WED AND WED NIGHT AS COLD FRONT AND FAIRLY
STRONG UPPER LEVEL TROF MOVES TRHOUGH IL. HIGHS 65 TO 70 MONDAY
CLIMB INTO THE LOWER 70S TUE...UPPER 60S AND LOWER 70S WED
(WARMEST IN SE IL) THEN COOLER INTO THE LOW TO MID 60S THU BEHIND
THE COLD FRONT AND UPPER 50S/LOWER 60S FRI.
07
&&
.AVIATION...
ISSUED 1155 PM CDT THU OCT 11 2012...FOR THE 06Z TAFS
REPORTS HAVE COME IN OF A FEW SPRINKLES REACHING THE GROUND FROM
SOME OF THE RADAR RETURNS THIS EVENING. THE HRRR MODELS IS
INDICATING A COUPLE MORE HOURS ISENTROPIC UPGLIDE AHEAD OF THE
COLD FRONT TO HELP FUEL A FEW MORE SPRINKLES THROUGH 07Z-08Z. NO
MEASURABLE RAIN IS EXPECTED AT ANY OF THE TERMINAL SITES...BUT WE
STILL INCLUDED VCSH FOR AN HOUR OR SO TO COVER THE POTENTIAL FOR
SLIGHTLY WET GROUND SURFACE.
WINDS HAVE BEEN GUSTING TO 16-18KT FROM THE NORTH-NORTHEAST AS THE
COLD FRONT PASSES. PIA IS THE ONLY TERMINAL TO HAVE SWITCHED
AROUND BY 0430Z...WITH BMI SHIFTING AT THIS TIME. WINDS SHOULD
REMAIN IN THE 08-12KT RANGE FROM THE NE FOR THE REST OF THE
NIGHT...THEN INCREASE INTO THE 14-16KT RANGE ON FRIDAY AS MIXING
HEIGHTS CLIMB TO AROUND 3-4K FT. WINDS SHOULD BECOME SOUTHEAST BY
LATE AFTERNOON AND DIMINISHING TO AROUND 8-10KT AHEAD OF THE NEXT
SYSTEM.
ANY PRECIP TOMORROW NIGHT SHOULD HOLD OFF UNTIL AFTER 06Z...BEYOND
THIS TAF PERIOD.
SHIMON
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1155 PM CDT THU OCT 11 2012
.DISCUSSION...
ISSUED 859 PM CDT THU OCT 11 2012
TWO MAIN WEATHER ISSUES ARE ON TAP THIS EVENING. A COLD FRONT
PUSHING ACROSS OUR AREA FROM NW TO SE IS EXPECTED TO BE A DRY
FRONTAL PASSAGE...WITH MID AND HIGH CLOUDS THE PRIMARY RESULT
ALONG WITH A WIND SHIFT FROM SW TO N.
THE OTHER ISSUE CENTERS ON ISENTROPIC LIFT AHEAD OF THE COLD FRONT
ACROSS SOUTHERN ILLINOIS INCLUDING THE SOUTHERN THIRD OF OUR
FORECAST AREA. INSTABILITY PARAMETERS SUPPORTIVE OF THUNDERSTORMS
WILL COME VERY CLOSE TO OUR SOUTHEASTERN COUNTIES...BUT SUFFICIENT
MOISTURE LEVELS APPEAR TO REMAIN SOUTH OF OUR AREA. RADAR RETURNS
WILL SHOW VIRGA ACROSS MOST OF OUR COUNTIES OVERNIGHT...BUT NO
PRECIP IS EXPECTED TO REACH THE GROUND. THEREFORE...WE WILL
CONTINUE WITH A DRY FORECAST THE REST OF THE NIGHT.
LOW TEMPS TONIGHT WILL VARY FROM UPPER 30S IN THE NW TO UPPER 40S
IN THE SE. VARYING CLOUD COVER WILL ALLOW FOR SOME COLDER SPOTS IN
THE EAST...BUT THE OVERALL COVERAGE LOOKS ON TRACK.
UPDATE FORECAST INFO WILL BE AVAILABLE SHORTLY.
SHIMON
&&
.AVIATION...
ISSUED 1155 PM CDT THU OCT 11 2012...FOR THE 06Z TAFS
REPORTS HAVE COME IN OF A FEW SPRINKLES REACHING THE GROUND FROM
SOME OF THE RADAR RETURNS THIS EVENING. THE HRRR MODELS IS
INDICATING A COUPLE MORE HOURS ISENTROPIC UPGLIDE AHEAD OF THE
COLD FRONT TO HELP FUEL A FEW MORE SPRINKLES THROUGH 07Z-08Z. NO
MEASURABLE RAIN IS EXPECTED AT ANY OF THE TERMINAL SITES...BUT WE
STILL INCLUDED VCSH FOR AN HOUR OR SO TO COVER THE POTENTIAL FOR
SLIGHTLY WET GROUND SURFACE.
WINDS HAVE BEEN GUSTING TO 16-18KT FROM THE NORTH-NORTHEAST AS THE COLD
FRONT PASSES. PIA IS THE ONLY TERMINAL TO HAVE SWITCHED AROUND BY
0430Z...WITH BMI SHIFTING AT THIS TIME. WINDS SHOULD REMAIN IN THE
08-12KT RANGE FROM THE NE FOR THE REST OF THE NIGHT...THEN
INCREASE INTO THE 14-16KT RANGE ON FRIDAY AS MIXING HEIGHTS CLIMB
TO AROUND 3-4K FT. WINDS SHOULD BECOME SOUTHEAST BY LATE AFTERNOON
AND DIMINISHING TO AROUND 8-10KT AHEAD OF THE NEXT SYSTEM.
ANY PRECIP TOMORROW NIGHT SHOULD HOLD OFF UNTIL AFTER 06Z...BEYOND
THIS TAF PERIOD.
SHIMON
&&
.PREV DISCUSSION...
ISSUED 304 PM CDT THU OCT 11 2012
MAIN CONCERN THIS PACKAGE INCLUDE TIMING OF PCPN FOR FRI NIGHT
THROUGH SUNDAY...WITH THE BIGGEST CHC OF PCPN BEING LATE SAT INTO
SAT NIGHT. THE OTHER CONCERNS WILL BE TEMPS AHEAD OF THIS WEEKEND
SYSTEM ALONG WITH ANOTHER CHC FOR PCPN TUE NIGHT THROUGH WED NIGHT
IN THE EXTENDED.
MODELS LOOK IN FAIRLY GOOD AGREEMENT WITH OVERALL UPPER LEVEL
PATTERN THROUGH THE PERIOD AND LOOK PRETTY SIMILAR WITH THE SFC
FEATURES IN THE SHORT TERM. HOWEVER...THE ECMWF AND GFS MODELS
DIFFER IN THE EXTENDED WITH HOW DEEP THE TROUGH WILL BE MIDDLE OF
THE WEEK AND THE SFC REFLECTION OF THAT ONCE THE FRONT MOVES
THROUGH ON WEDNESDAY.
SHORT TERM...TONIGHT THROUGH SUNDAY
A COLD FRONT....CURRENTLY LOCATED IN SOUTHERN IA/WI WILL DROP
THROUGH THE CWA THIS EVENING AND COME THROUGH DRY SINCE ALL
MOISTURE IS WELL SOUTH OF THE AREA. BEHIND THIS FRONT WILL BE ONE
MORE DRY DAY TOMORROW WITH BELOW NORMAL TEMPS. THIS HIGH PRSS WILL
QUICKLY MOVE EAST TOMORROW AND TOMORROW NIGHT AND A SOUTHERLY
RETURN FLOW WILL QUICKLY SETUP FOR FRI NIGHT AND BRING PCPN BACK
TO THE NORTHWESTERN PARTS OF THE CWA FOR LATE TOMORROW
NIGHT...AFTER MIDNIGHT. PCPN WILL NOT BE MUCH BUT IT WILL BE THE
START TO A COUPLE OF PERIODS OF SHOWERS AND THUNDERSTORMS OVER THE
AREA FOR THE WEEKEND. ONCE THIS FIRST ROUND OF PCPN MOVES THROUGH
EARLY SAT MORNING...MOST OF CWA SHOULD BE IN THE WARM SECTOR AND
DRY...HOWEVER...THERE IS STILL SOME CHANCES OF PCPN IN THE NORTH
AND NORTHWEST DURING THE DAY ON SATURDAY...AS THESE AREAS WILL BE
CLOSEST TO THE DYNAMICS AND WARM FRONTAL ZONE. THEN OCCASIONAL
THUNDERSTORMS WILL MOVE THROUGH THE CWA BEGINNING SAT EVENING AND
CONTINUE THROUGH THE ENTIRE CWA FOR OVERNIGHT SAT NIGHT. SVR WX
DYNAMICS LOOKS BEST OUT WEST FOR SAT AFTERNOON AND EVENING SO
EXPECTING STORMS TO DEVELOP OUT WEST AND THEN MOVE INTO THE AREA
SAT EVENING AND CONTINUE INTO OVERNIGHT SAT NIGHT. SVR WX WILL
CONTINUE TO BE POSSIBLE DURING THE STORMS MOVING THROUGH AND
POSSIBLE THAT STORMS WILL DEVELOP INTO A SQUALL LINE WITH DAMAGING
WINDS BEING MAIN SVR WX THREAT. ONCE THE MAIN EVENT MOVES THROUGH
THE COLD FRONT WILL STILL BE WEST OF THE AREA AND THEN MOVE
THROUGH THE CWA DURING THE DAY ON SATURDAY. HOWEVER...WILL ONLY BE
HOLDING ONTO A CHC OF PCPN SUNDAY IN THE EAST SINCE MOST OF THE
PCPN WILL BE WITH THE STORMS FROM OVERNIGHT.
TEMPS WILL START BELOW NORMAL TOMORROW BUT THEN WARM TO WELL ABOVE
NORMAL AHEAD OF THE FRONT COMING FOR SAT NIGHT/SUNDAY. TEMPS
SUNDAY SHOULD STILL BE AROUND NORMAL. BLEND OF GUIDANCE LOOKS TO BE
BEST FORECAST FOR TEMPS.
LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
PATTERN WILL THEN SHIFT TO MORE OF A ZONAL FLOW FOR MOST OF THE
EXTENDED PERIOD. MODELS HAVE ANOTHER TROUGH AND FRONTAL SYSTEM
MOVING THROUGH THE AREA DURING THE MIDDLE OF THE WEEK. THIS SYSTEM
WILL MOVE THROUGH QUICKLY AND BRING ANOTHER CHC OF THUNDERSTORMS
TO THE REGION FOR TUE NIGHT THROUGH WED NIGHT.
TEMPS WILL BE AROUND NORMAL THROUGH THE PERIOD EXCEPT AFTER THE
MIDWEEK FRONT...WHEN TEMPS WILL THEN FALL TO JUST BELOW NORMAL.
AUTEN
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1229 AM EDT FRI OCT 12 2012
.UPDATE...
ISSUED AT 1230 AM EDT FRI OCT 12 2012
BASIC CLEAR SKIES AND LIGHT WINDS. MAIN CONSIDERATION FOR THIS UPDATE
IS THE TEMPERATURES AND POSSIBILITY OF FOG/FROST. MINOR TWEAKS TO THE
GRIDS TO ALIGN WITH CURRENT OBS BUT NO CHANGES TO ZONE FORECAST.
UPDATE ISSUED AT 915 PM EDT THU OCT 11 2012
UPDATED FORECAST TO REMOVE THUNDER CHANCES. MODELS ARE REALLY LACKING
ANY INSTABILITY TONIGHT. THUS...DO NOT SEE ANY SUPPORT FOR THUNDER.
AS FAR AS THE FROST POTENTIAL...COOP MOS GUIDANCE HAS THE COLDEST
OVERNIGHT LOW AT 36 WHICH IS PROBABLY THE ABSOLUTE MINIMUM
TEMPERATURES COULD REACH TONIGHT GIVEN THE INCREASING CLOUD COVER
LATE. THUS...GOING TO REMOVE THE MENTION OF FROST. AS FAR AS
PRECIPITATION CHANCES...THE RUC AND HRRR ARE BOTH INDICATING
SCATTERED SHOWERS SPREADING INTO OUR SOUTHWEST TOWARDS DAWN.
THUS...PLAN TO BRING THE CHANCE OF RAIN UP TO BETWEEN 30 AND 40
PERCENT. IT LOOKS LIKE THE THREAT FOR RAIN WILL BE SHORT LIVED AND
WILL BE ON THE WAY OUT BY MID MORNING. THE ZFP...HWO AND NDFD HAVE
ALREADY BEEN UPDATED.
UPDATE ISSUED AT 729 PM EDT THU OCT 11 2012
STILL A BIT OF UNCERTAINTY WITH EXACTLY HOW MUCH AREAL COVERAGE THERE
WILL BE TONIGHT. LATEST HRRR (20Z) SHOWS A BIT MORE PRECIPITATION
COMING ACROSS OUR SOUTHWEST ZONES AFTER 08Z. HOWEVER...PREVIOUS RUNS
HAD ALMOST NOTHING. IT WILL BE INTERESTING TO SEE IF THE NEW RUN OF
THE HRRR TAKES HOLD OR IF IT BACKS OFF WITH THE NEXT RUN.
REGARDLESS...GOING TO BE WATCHING THINGS UPSTREAM AS CONVECTION IS
EXPECTED TO DEVELOP ACROSS SOUTHERN MISSOURI AND WESTERN
KENTUCKY...THEN SPREAD INTO THE AREA LATE. IF THE CONVECTION DOES NOT
MATERIALIZE...THIS WOULD OBVIOUSLY LEND ITSELF TO A DRIER FORECAST.
ITS GOING TO BE A WAITING GAME OVER THE NEXT 3 TO 5 HOURS. BASED ON
THE LACK OF SIGNIFICANT FORCING AND PRESENT ACTIVITY UPSTREAM...MY
GUT FEELING IS THAT WE WILL PROBABLY END UP ON THE DRIER SIDE OF
THINGS. HOWEVER...PLAN TO WAIT THINGS OUT AND PERHAPS SEE WHAT SOME
OF THE NEW 00Z MODELS COME IN WITH. FOR NOW...MADE SIGNIFICANT HOURLY
TWEAKS TO TEMPERATURES AND DEWPOINTS TO REPRESENT THE QUICKLY FALLING
VALLEY TEMPS THIS EVENING. PLAN TO REWORK TEMPERATURES FURTHER TO
SHOW MORE STEADY OR SLOWLY FALLING TEMPS IN THE SOUTHWEST WITH THE
INCREASING CLOUD COVER. GRIDS HAVE BEEN SAVED AND SENT TO NDFD.
&&
.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 322 PM EDT THU OCT 11 2012
A WARM FRONT WILL APPROACH FROM THE SOUTHWEST WHILE A WEAKENING COLD
FRONT ENTERS THE REGION FROM THE NORTHWEST LATE TONIGHT. ELEVATED
WARM AIR ADVECTION NORTH OF THE WARM FRONT IS FORECAST TO PRODUCE A
SATURATED WARM LAYER AROUND 800-850 MB OVER OUR SW COUNTIES LATE
TONIGHT AND FRIDAY MORNING...RESULTING IN INCREASING CLOUDS. FORECAST
SOUNDINGS SHOW A CONVECTIVE CAP OVER TOP OF THIS LAYER ACROSS MOST OF
THE FORECAST AREA. HOWEVER...THERE IS ONLY A THIN CAP AROUND 650 MB
AT 12Z FRIDAY IN OUR FAR SW...AND WILL CONTINUE TO USE 20 PERCENT
POPS FOR TSRA THERE LATE TONIGHT AND EARLY FRIDAY.
DRIER AIR WILL WORK IN FROM THE NORTH BEHIND THE DECAYING COLD FRONT
DURING THE DAY FRIDAY AND BRING A RETURN TO CLEAR SKIES FOR MOST OF
FRIDAY NIGHT...AS SURFACE HIGH PRESSURE CONTROLLING OUR WEATHER
PASSES BY TO OUR NE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 322 PM EDT THU OCT 11 2012
AN ACTIVE AND SOMEWHAT PROGRESSIVE PATTERN LOOKS TO BE IN PLACE FOR
THE EXTENDED PERIOD. THE UPPER LEVEL PATTERN THROUGH THE EARLY PART
OF THE EXTENDED IS HIGHLIGHTED BY A BROAD TROUGH OVER THE UPPER
GREAT LAKES WITH SUCCESSIVE SHORTWAVES MOVING THROUGH THE NORTHERN
PLAINS AND INTO THE GREATER LAKES. BY SUNDAY...THE BROAD TROUGH OVER
THE GREAT LAKES FINALLY SHIFTS EAST INTO THE ATLANTIC AS THE NEXT
WAVE MOVES THROUGH THE PLAINS INTO THE UPPER MS VALLEY. RECENT RUNS
OF THIS WAVE HAVE SHOWN A GENERAL INCREASE IN STRENGTH AS THE RECENT
RUN OF THE GFS SHOWS A NEGATIVELY TILTED TROUGH MOVING INTO THE OHIO
VALLEY SUNDAY EVENING. GIVEN THE FLOW...WILL WAIT FOR SOME LATER
RUNS TO GAUGE THE LEVEL OF CONVECTION AS RIGHT NOW...INSTABILITY
LOOKS TO BE IN QUESTION. 12Z RUNS ALONG WITH THE ALL BLEND ARE
COMING IN WITH A BIT OF INSTABILITY SO WILL THROW IN CHANCE THUNDER
FOR SUNDAY.
BY MONDAY NIGHT...HIGH PRESSURE FILTERS IN BEHIND THE FRONT WITH
ANOTHER EARLY FALL LIKE AIR MASS POISED TO ADVECT IN. HOWEVER...THE
PATTERN SUGGESTS THE FRONT TO SLOW OVER THE APPALACHIAN CHAIN FOR
MONDAY NIGHT AND INTO TUESDAY. THIS COULD SLOW THE IMPACT OF THE AIR
MASS BEHIND THE FRONT AND KEEP TEMPS FROM BOTTOMING OUT AT THE
SURFACE. WILL ADDRESS THESE FORECAST PROBLEMS BASED ON THE ALL
MODELS BLEND SOLUTION. ALSO WILL KEEP CLOUD COVER LINGERING IN THE
EASTERN RANGES THROUGH MONDAY NIGHT AS THE FRONT WILL LIKELY HANG UP
ALONG THE APPALACHIAN RANGE.
HIGH PRESSURE WILL SETTLE FINALLY BY TUESDAY BEFORE THE NEXT WAVE
BEGINS TO IMPACT THE AREA LATE WEDNESDAY. THE SOMEWHAT PROGRESSIVE
PATTERN IN THE EXTENDED AND LACK OF AMPLITUDE WILL LEAD TO MORE
SEASONAL LOWS FOR EASTERN KENTUCKY IN THE MID TO UPPER 40S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1230 AM EDT FRI OCT 12 2012
VFR CONDITIONS WILL CONTINUE OVER THE NEXT 24 HOURS. THE ONLY CHANCE
TO TEMPORARILY GO TO MVFR WILL BE AROUND DAYBREAK...AS CIGS LOWER TO
AROUND 3.5K FT WITH VCSH NEAR LOZ/SME/EKQ/1A6. THE CIGS COULD
TEMPORARILY DROP TO 3KFT OR SLIGHTLY LOWER...BUT TOO MUCH UNCERTAINTY
TO GO THAT LOW AT THIS TIME. OTHERWISE...CIG HEIGHTS WILL AGAIN BE ON
THE INCREASE TOMORROW BEFORE SKIES CLEAR FROM THE NORTH IN THE
AFTERNOON AND EVENING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DUSTY
SHORT TERM...HAL
LONG TERM...SHALLENBERGER
AVIATION...DUSTY
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
301 AM EDT FRI OCT 12 2012
.SYNOPSIS...
A COLD FRONT WILL DROP SOUTHEAST TONIGHT...AND BRING A CHANCE FOR
RAIN SHOWERS...MAINLY OVER CENTRAL NEW YORK. HIGH PRESSURE WILL
BUILD INTO THE REGION BEHIND THIS FRONT ON FRIDAY...AND BRING
CLEAR SKIES AND COLD AIR FRIDAY NIGHT ENDING THE GROWING SEASON.
DRY AND MILDER CONDITIONS ARE EXPECTED ON SATURDAY. THE NEXT
CHANCE FOR SHOWERS WILL COME SATURDAY NIGHT AND SUNDAY AS A WARM
FRONT MOVES THROUGH THE REGION.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
10 PM UPDATE...
FNT AND ASSOCIATED PCPN SEEMS TO BE HOLDING UP A BIT JUST NORTH OF
THE FCST AREA...AWAITING THE WV MVG THRU THE CNTRL LAKES. XPCT THE
FNT AND PCPN TO BEGIN TO MVE SEWRD ONCE AGAIN LTR TNGT AS THE WV
APRCHS. HRRR SEEMS TO HAVE A GOOD HANDLE ON THE ADVANCE OF THE
PCPN SHIELD. FCSTD TEMPS IN GOOD SHAPE...JUST SOME MINOR
ADJUSTMENTS FOR THE UNEQUAL COOLING OF THE HILLS AND VLYS IN THE
AREA. TWEEKED THE MINS DOWN JUST A BIT...CLSR IN LINE WITH THE
BLENDED MOS GUID. PRVS DISC CONTS BLO.
CDFNT WILL DROP SEWD TNGT WITH A BAND OF CLDS AND -SHRA. THE
-SHRA MAY DIMINISH AS THE FNT HEADS INTO E PA TWDS DAYBREAK...AND
WE`VE KEPT THE HIEST POPS ACRS CNTRL NY TNGT (LOW LIKELY/HI CHC
POPS). TNGT`S FCST MINS INDICATE BEST POTNL FOR ISOLD FROST WILL
ACRS THE CATSKILLS AND PORTIONS OF THE POCONOS WHERE CLDS WILL BE
LATER TO MOV IN...BUT TEMPS ARE MARGINAL AND WITH CLD DECK FCST TO
MOV IN LATER TNGT THINK POTNL IS MARGINAL (IN ADDN...MUCH COLDER
TEMPS ARE IN THE CARDS FOR FRI NGT). WE LEANED TWDS THE WARMER
SIDE OF GDNC FOR TNGT`S MINS GIVEN EXPECTATION OF SOME WIND AND
XPCTD INCRS IN CLD CVR LATER TNGT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/...
RESIDUAL MSTR BEHIND THE FNT..AIDED BY LAKE ONTARIO...IS XPCTD TO
PERSIST TMRW MRNG ACRS CNTRL NY...WITH MAYBE A FEW -SHRA. WE CAN`T
TOTALLY RULE OUT A FEW FLAKES MIXING IN OVER THE HIEST TRRN TMRW
MRNG BUT IT LOOKS VERY MARGINAL AND THEREFORE WON`T ADD TO THE WX
GRIDS.
STRONG DEEP SUBSIDENCE BEHIND THE FNT VERY EVIDENT IN THE OMEGA
T-H XSXNS AFTER 18Z WHICH WILL HELP ERODE/DSPT THE CLD CVR. THERE
COULD BE A FEW STRAY CLDS ACRS OUR FAR NW/NRN ZONES...BUT ALL IN
ALL AN XCLNT RADIATIONAL COOLING SITUATION WILL SET UP. ISSUED A
FROST WATCH FOR FRI NGT AS IT APEARS THIS WILL BE THE END OF THE
GROWING SEASON.
THE HIGH MOVS OFFSHORE ALLOWING A SW FLOW TO DVLP ON SAT. WE`LL
LIKELY SEE AN INCRS IN MID/UPR CLDS SAT AFTN IN ADVANCE OF THE NXT
S/WV. NON-DIURNAL TEMP TRENDS...OR STEADY TEMPS APPEAR LIKELY SAT
NGT IN ADVANCE OF THE WMFNT MAINLY ALONG THE LAKE PLAIN DUE TO
INCRSNG SW FLOW ON SAT NGT. XPCT SHRA TO OVERSPREAD THE RGN AS THE
WMFNT APRCHS...WITH THE BEST CHCS ACRS CNTRL AND NRN ZONES WHERE
ISEN LIFT IS STRONGEST.
THE WMFNT RAINS SHUD LIFT NWD ON SUNDAY MRNG...AND WOULD NOT BE
SUPRISED TO SEE MOST OF THE CWA REMAIN DRY ON SUNDAY...BUT WE LEFT
LOW CHC POPS IN FOR SUNDAY AFTN FOR CONSISTENCY. 925 TEMPS ON SUNDAY
ACRS THE FINGER LAKES AND CNTRL SRN TIER WOULD SUPPORT MAXES WELL
INTO THE U70S WE HAD FULL SUN...BUT IT APPEARS THAT AT A MINIMUM
WE`LL HAVE A BKN-OVC MID/UPR DECK WHICH WILL TEMPER MAXES. SO
STAYED CLOSE TO MOS GDNC WITH MAXES APRCHNG 70 WRN ZONES...WITH
MAXES IN THE L60S FAR SE ZONES.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
3 AM UPDATE...CURRENT 00Z MEDIUM RANGE MODEL GUIDANCE REMAINS
CONSISTENT WITH PREVIOUS RUNS. CURRENT FORECAST IN GOOD SHAPE WITH
NO SIGNIFICANT CHANGES NEEDED.
PREVIOUS DISC...
2 PM UPDATE...LONG TERM GUIDANCE REMAINS IN GOOD AGREEMENT THAT
THE BEST SHOT AT PRECIPITATION WILL COME EARLY MONDAY WITH A COLD
FRONT. DRIER AIR WILL BUILD IN BEHIND THE FRONT MONDAY BUT WILL
MAINTAIN CHANCE POPS DURING THE DAY...ESPECIALLY UP NORTH...WITH
AN H5 TROF STILL MOVING THROUGH.
WEAK RIDING BUILDS IN TUESDAY AND WEDNESDAY AND WITH A DEVELOPING
SOUTHERLY FLOW...WE WILL ONCE AGAIN TURN MILD. HIGHS BY WEDNESDAY
LOOK TO BE BACK INTO THE 60S AS 850 TEMPS CLIMB TOWARD +6C ON THE
0Z EURO. WITH THE NEW 12Z GFS NUMBERS COMING IN CLOSER TO +10...WE
MAY EVEN BE A TAD TOO COOL RIGHT NOW IN OUR GRIDS. NEXT SHOT AT
RAIN COMES THURSDAY WITH THE NEXT FRONT.
&&
.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
A COLD FRONT CURRENTLY DROPPING SOUTH FROM LAKE ONTARIO WILL PASS
THROUGH THE TERMINALS EARLY THIS MORNING. OCCASIONAL MVFR SHOWERS
DUE TO CIGS WILL OCCUR NEAR THIS BOUNDARY. AT KRME/KSYR ACTIVITY
WILL OCCUR BETWEEN 08Z-12Z, FOR KITH/KBGM/KELM BETWEEN 09Z-14Z AND
AT KAVP BETWEEN 13-15Z. AT KITH/KBGM, MVFR CIGS WILL PREVAIL
DURING THIS PERIOD WITH OCCASIONAL LOW MVFR CIGS. BY LATE MORNING
SHOWERS WILL END BUT A BROKEN STRATO CU DECK AROUND 4K FT WILL
PERSIST UNTIL MID/LATE AFTERNOON WHEN SKIES WILL SCATTER OUT THEN
CLEAR FOR THE OVERNIGHT PERIOD.
SOUTHWEST WINDS AROUND 10 KNOTS BECOMING NORTHWEST WITH FROPA
AROUND 10 KNOTS THEN INCREASING LATER THIS MORNING TO 12-15 KNOTS
WITH GUSTS 20-25 KNOTS. WINDS WILL DIMINISH LATE THIS AFTERNOON
THEN BECOME LIGHT OVERNIGHT.
OUTLOOK...
SAT/SUN...VFR.
SUN NGT/MON...MVFR IN SHRA.
TUE...VFR.
&&
.CLIMATE...
NEAR RECORD LOW TEMPERATURES POSSIBLE SATURDAY MORNING OCTOBER
13TH. A COLD HIGH PRESSURE SYSTEM IS EXPECTED TO COVER THE REGION
BY SATURDAY MORNING AND COULD BRING WIDESPREAD FROST AND FREEZING
CONDITIONS TO THE REGION. RECORD LOWS THAT COULD BE CHALLENGED ARE
AS FOLLOWS: RECORD (YEAR) SAT AM FORECAST LOW
GREATER BINGHAMTON AIRPORT 28 (1993) 27
SCRANTON/WILKES BARRE AIRPORT 29 (1993) 28
SYRACUSE AIRPORT 29 (2006) 28
ITHACA AIRPORT 25 (1964) 26
ELMIRA/CORNING AIRPORT 25 (1951) 24
ROME/GRIFFIS AIRPORT 26 (1993) 26
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...FREEZE WATCH FROM THIS EVENING THROUGH SATURDAY MORNING FOR
PAZ038>040-043-044-047-048-072.
NY...FREEZE WATCH FROM THIS EVENING THROUGH SATURDAY MORNING FOR
NYZ009-015>018-022>025-036-037-044>046-055>057-062.
&&
$$
SYNOPSIS...
NEAR TERM...DGM
SHORT TERM...
LONG TERM...HEDEN/RRM
AVIATION...RRM
CLIMATE...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
144 AM EDT FRI OCT 12 2012
.SYNOPSIS...
A COLD FRONT WILL DROP SOUTHEAST TONIGHT...AND BRING A CHANCE FOR
RAIN SHOWERS...MAINLY OVER CENTRAL NEW YORK. HIGH PRESSURE WILL
BUILD INTO THE REGION BEHIND THIS FRONT ON FRIDAY...AND BRING
CLEAR SKIES AND COLD AIR FRIDAY NIGHT ENDING THE GROWING SEASON.
DRY AND MILDER CONDITIONS ARE EXPECTED ON SATURDAY. THE NEXT
CHANCE FOR SHOWERS WILL COME SATURDAY NIGHT AND SUNDAY AS A WARM
FRONT MOVES THROUGH THE REGION.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
10 PM UPDATE...
FNT AND ASSOCIATED PCPN SEEMS TO BE HOLDING UP A BIT JUST NORTH OF
THE FCST AREA...AWAITING THE WV MVG THRU THE CNTRL LAKES. XPCT THE
FNT AND PCPN TO BEGIN TO MVE SEWRD ONCE AGAIN LTR TNGT AS THE WV
APRCHS. HRRR SEEMS TO HAVE A GOOD HANDLE ON THE ADVANCE OF THE
PCPN SHIELD. FCSTD TEMPS IN GOOD SHAPE...JUST SOME MINOR
ADJUSTMENTS FOR THE UNEQUAL COOLING OF THE HILLS AND VLYS IN THE
AREA. TWEEKED THE MINS DOWN JUST A BIT...CLSR IN LINE WITH THE
BLENDED MOS GUID. PRVS DISC CONTS BLO.
CDFNT WILL DROP SEWD TNGT WITH A BAND OF CLDS AND -SHRA. THE
-SHRA MAY DIMINISH AS THE FNT HEADS INTO E PA TWDS DAYBREAK...AND
WE`VE KEPT THE HIEST POPS ACRS CNTRL NY TNGT (LOW LIKELY/HI CHC
POPS). TNGT`S FCST MINS INDICATE BEST POTNL FOR ISOLD FROST WILL
ACRS THE CATSKILLS AND PORTIONS OF THE POCONOS WHERE CLDS WILL BE
LATER TO MOV IN...BUT TEMPS ARE MARGINAL AND WITH CLD DECK FCST TO
MOV IN LATER TNGT THINK POTNL IS MARGINAL (IN ADDN...MUCH COLDER
TEMPS ARE IN THE CARDS FOR FRI NGT). WE LEANED TWDS THE WARMER
SIDE OF GDNC FOR TNGT`S MINS GIVEN EXPECTATION OF SOME WIND AND
XPCTD INCRS IN CLD CVR LATER TNGT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY/...
RESIDUAL MSTR BEHIND THE FNT..AIDED BY LAKE ONTARIO...IS XPCTD TO
PERSIST TMRW MRNG ACRS CNTRL NY...WITH MAYBE A FEW -SHRA. WE CAN`T
TOTALLY RULE OUT A FEW FLAKES MIXING IN OVER THE HIEST TRRN TMRW
MRNG BUT IT LOOKS VERY MARGINAL AND THEREFORE WON`T ADD TO THE WX
GRIDS.
STRONG DEEP SUBSIDENCE BEHIND THE FNT VERY EVIDENT IN THE OMEGA
T-H XSXNS AFTER 18Z WHICH WILL HELP ERODE/DSPT THE CLD CVR. THERE
COULD BE A FEW STRAY CLDS ACRS OUR FAR NW/NRN ZONES...BUT ALL IN
ALL AN XCLNT RADIATIONAL COOLING SITUATION WILL SET UP. ISSUED A
FROST WATCH FOR FRI NGT AS IT APEARS THIS WILL BE THE END OF THE
GROWING SEASON.
THE HIGH MOVS OFFSHORE ALLOWING A SW FLOW TO DVLP ON SAT. WE`LL
LIKELY SEE AN INCRS IN MID/UPR CLDS SAT AFTN IN ADVANCE OF THE NXT
S/WV. NON-DIURNAL TEMP TRENDS...OR STEADY TEMPS APPEAR LIKELY SAT
NGT IN ADVANCE OF THE WMFNT MAINLY ALONG THE LAKE PLAIN DUE TO
INCRSNG SW FLOW ON SAT NGT. XPCT SHRA TO OVERSPREAD THE RGN AS THE
WMFNT APRCHS...WITH THE BEST CHCS ACRS CNTRL AND NRN ZONES WHERE
ISEN LIFT IS STRONGEST.
THE WMFNT RAINS SHUD LIFT NWD ON SUNDAY MRNG...AND WOULD NOT BE
SUPRISED TO SEE MOST OF THE CWA REMAIN DRY ON SUNDAY...BUT WE LEFT
LOW CHC POPS IN FOR SUNDAY AFTN FOR CONSISTENCY. 925 TEMPS ON SUNDAY
ACRS THE FINGER LAKES AND CNTRL SRN TIER WOULD SUPPORT MAXES WELL
INTO THE U70S WE HAD FULL SUN...BUT IT APPEARS THAT AT A MINIMUM
WE`LL HAVE A BKN-OVC MID/UPR DECK WHICH WILL TEMPER MAXES. SO
STAYED CLOSE TO MOS GDNC WITH MAXES APRCHNG 70 WRN ZONES...WITH
MAXES IN THE L60S FAR SE ZONES.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
2 PM UPDATE...LONG TERM GUIDANCE REMAINS IN GOOD AGREEMENT THAT
THE BEST SHOT AT PRECIPITATION WILL COME SUNDAY NIGHT INTO EARLY
MONDAY WITH A COLD FRONT. TEMPS WILL BE MILD SUNDAY NIGHT AHEAD OF
THE FRONT...WITH 40S TO LOWER 50S EXPECTED. DRIER AIR WILL BUILD
IN BEHIND THE FRONT MONDAY BUT WILL MAINTAIN CHANCE POPS DURING
THE DAY...ESPECIALLY UP NORTH...WITH AN H5 TROF STILL MOVING THROUGH.
WEAK RIDING BUILDS IN TUESDAY AND WEDNESDAY AND WITH A DEVELOPING
SOUTHERLY FLOW...WE WILL ONCE AGAIN TURN MILD. HIGHS BY WEDNESDAY
LOOK TO BE BACK INTO THE 60S AS 850 TEMPS CLIMB TOWARD +6C ON THE
0Z EURO. WITH THE NEW 12Z GFS NUMBERS COMING IN CLOSER TO +10...WE
MAY EVEN BE A TAD TOO COOL RIGHT NOW IN OUR GRIDS. NEXT SHOT AT
RAIN COMES THURSDAY WITH THE NEXT FRONT.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
A COLD FRONT CURRENTLY DROPPING SOUTH FROM LAKE ONTARIO WILL PASS
THROUGH THE TERMINALS EARLY THIS MORNING. OCCASIONAL MVFR SHOWERS
DUE TO CIGS WILL OCCUR NEAR THIS BOUNDARY. AT KRME/KSYR ACTIVITY
WILL OCCUR BETWEEN 08Z-12Z, FOR KITH/KBGM/KELM BETWEEN 09Z-14Z AND
AT KAVP BETWEEN 13-15Z. AT KITH/KBGM, MVFR CIGS WILL PREVAIL
DURING THIS PERIOD WITH OCCASIONAL LOW MVFR CIGS. BY LATE MORNING
SHOWERS WILL END BUT A BROKEN STRATO CU DECK AROUND 4K FT WILL
PERSIST UNTIL MID/LATE AFTERNOON WHEN SKIES WILL SCATTER OUT THEN
CLEAR FOR THE OVERNIGHT PERIOD.
SOUTHWEST WINDS AROUND 10 KNOTS BECOMING NORTHWEST WITH FROPA
AROUND 10 KNOTS THEN INCREASING LATER THIS MORNING TO 12-15 KNOTS
WITH GUSTS 20-25 KNOTS. WINDS WILL DIMINISH LATE THIS AFTERNOON
THEN BECOME LIGHT OVERNIGHT.
OUTLOOK...
SAT/SUN...VFR.
SUN NGT/MON...MVFR IN SHRA.
TUE...VFR.
&&
.CLIMATE...
NEAR RECORD LOW TEMPERATURES POSSIBLE SATURDAY MORNING OCTOBER
13TH. A COLD HIGH PRESSURE SYSTEM IS EXPECTED TO COVER THE REGION
BY SATURDAY MORNING AND COULD BRING WIDESPREAD FROST AND FREEZING
CONDITIONS TO THE REGION. RECORD LOWS THAT COULD BE CHALLENGED ARE
AS FOLLOWS: RECORD (YEAR) SAT AM FORECAST LOW
GREATER BINGHAMTON AIRPORT 28 (1993) 27
SCRANTON/WILKES BARRE AIRPORT 29 (1993) 28
SYRACUSE AIRPORT 29 (2006) 28
ITHACA AIRPORT 25 (1964) 26
ELMIRA/CORNING AIRPORT 25 (1951) 24
ROME/GRIFFIS AIRPORT 26 (1993) 26
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...FREEZE WATCH FROM THIS EVENING THROUGH SATURDAY MORNING FOR
PAZ038>040-043-044-047-048-072.
NY...FREEZE WATCH FROM THIS EVENING THROUGH SATURDAY MORNING FOR
NYZ009-015>018-022>025-036-037-044>046-055>057-062.
&&
$$
SYNOPSIS...
NEAR TERM...DGM
SHORT TERM...
LONG TERM...HEDEN
AVIATION...RRM
CLIMATE...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
352 AM EDT FRI OCT 12 2012
.SYNOPSIS...
A COLD FRONT WILL SWEEP THROUGH THE STATE EARLY TODAY. A MASSIVE
ANTICYCLONE WILL PRODUCE CLEAR CALM CONDITIONS FOR A WIDESPREAD
FROST SATURDAY. A MOISTURE PLUME AND WARMER AIR COULD BRING
SHOWERS SATURDAY NIGHT INTO SUNDAY.
A TROUGH OVER THE EASTERN UNITED STATES NEXT WEEK WILL SET UP TO
OUR WEST. A RELATIVELY DRY AND SEASONABLY WARM PERIOD OF WEATHER
IS EXPECTED FOR MOST OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
SATELLITE IMAGERY...IR AND 11-3.9 MICRON SHOW CLOUDS OVER
NORTHWESTERN PA. THE FIRST SURGES INTO WEST CENTRAL AREAS HAVE
DISSIPATED. MOST OF CENTRAL AND SOUTHERN PA ARE SPOT ON CLEAR.
THE CLEAR AREAS WITH DEW POINTS IN THE LOWER 30S HAVE PRODUCED
SOME REMARKABLE TEMPERATURE GRADIENTS. READINGS IN THE UPPER 20S
LOWER 30S. INCREDIBLE RANGE 29 IN PARTS OF CAMBRIA COUNTY AND 31
IN PARTS OF BLAIR COUNTY. MUCH COLDER THAN THE REGIONAL AIRPORTS.
WHERE KJST IS 39 AND KAOO IS 43 AND 44 AT KUNV. SOME PASSING
CLOUDS KEPT SOUTHERN AREAS IN 40S. TEMPERATURES SHOULD BEGIN TO
REBOUND IN EXTREME NORTHWEST WHERE CLOUDS MOVING IN.
THE RURAL NON-AIRPORT OBS REFLECT PATCHY FROST IN RURAL AREAS.
KCLE AND KBUF SHOW VERY LITTLE PRECIPITATION TO OUR WEST. 4KM NAM
AND HRRR ARE NOT VERY AGGRESSIVE WITH RAINFALL EITHER. LOWERED POPS
IN EARLY AM IN NW TO CHANCE.
THE 4KM NAM AT 0000 UTC AND RECENT 0,1,2, 3 UTC RAP DATA IMPLY
SHOWERS IN THE 10-12Z RANGE IN NW PA. BUT THE WEAK SHOWERS SEEM TO
FALL APART AS THEY MOVE INTO THE DRY AIR TO THE SOUTH AND EAST.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM SATURDAY/...
THE COLD FRONT WILL PUSH SOUTH ACROSS THE REGION BTWN 09Z-16Z WITH
THE CHANCE OF SOME LINGERING SHOWERS DURING THE FIRST PART OF THE
MORNING...ESPECIALLY OVER THE NWRN HALF OR SO OF THE STATE.
FRONTAL TIMING IS GOOD WITH THE 13KM RAP.
SHORT RANGE MODELS AGREE IN QUICKLY MOVING THE SFC HIGH AND LOW
PWAT AIR OVERHEAD BY AFTN...WHICH SHOULD BRING CLEARING SKIES.
ENSEMBLE MEAN 850 TEMPS ARE SUPPORTIVE OF HIGH TEMPS FROM JUST THE
M40S OVER THE N MTNS...TO THE U50S ACROSS THE LOWER SUSQ VALLEY. A
FAIRLY TIGHT PRES GRADIENT BEHIND FRONT WILL RESULT IN A BREEZY
DAY. BUFKIT SOUNDINGS SUPPORT FREQUENT GUSTS TO ARND 20KT BY AFTN.
RAP AND MOST GUIDANCE SUGGEST HIGHS RANGE FROM LOWER 40S NW TO
AROUND 60 EXTREME SOUTHEAST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
SATURDAY SHOULD GET OFF TO A FROSTY START BUT WITH THE FLOW AROUND
THE RETREATING ANTICYCLONE LATE AFTERNOON TEMPERATURES SHOULD
REBOUND NICELY TO NEAR NORMAL. THE PW SURGE TO OUR WEST SHOULD
INCREASE OUR CLOUDS. BUT SHOULD BE A DRY DAY.
THE WARM AIR...ABOUT +1.5 SIGMA ABOVE NORMAL MOVES OVER SATURDAY
NIGHT INTO LATE SUNDAY...ALONG WITH A SURGE OF ABOVE NORMAL PW
IMPLYING A GOOD CHANCE AT RAIN OVERNIGHT SATURDAY OR INTO SUNDAY
AM. THIS IS THE BEST MOISTURE PLUME FOR THE NEXT 6-7 DAYS. IF WE
GET RAIN THIS SHOULD BE OUR BEST OF SOME RAINFALL. THE HIGH PW AIR
AND IMPLIED MOISTURE WILL KEEP TEMPERATURES UP SATURDAY NIGHT.
SUNDAY HAS A GOOD CHANCE OF RAIN IN THE NORTH THOUGH POPS NOT
IMPRESSIVE IN MOS...BETTER IN GEFS.
A WEAK COLD FRONT COULD TRIGGER SHOWERS MONDAY AS THE LAST OF THE
HIGH PW AIR IS PUSHED EAST BY A MORE N-S FRONT.
OUR PW VALUES STAY CLOSE TO NORMAL WHICH TYPICALLY MEANS LOW
CHANCE OF SIGNIFICANT RAINFALL. THE 850 HPA TEMPERATURES TOO ARE
NEAR NORMAL. ANY RAINFALL POTENTIAL WOULD BE LOW AND AMOUNTS
SCANT. THERE ARE IMPLIED WEAK FRONTAL BOUNDARIES IN THE ENSEMBLES
BUT NOTHING OF NOTE. TEMPERATURES SHOULD BE NEAR NORMAL WITH BELOW
NORMAL RAINFALL MOST OF THE WEEK. AT THIS TIME A TROUGH COULD
TRIGGER LIGHT SHOWERS THURS-FRI. BUT THIS WILL LIKELY CHANGE AS
VERY HIGH UNCERTAINTY.
INTERESTING TO WATCH SURGE OF HIGH PW WELL OFF THE ATLANTIC COAST AND
THE DEEP LOW PRESSURE IN THE GUIDANCE WITH THE LATE SEASON
TROPICAL STORM PATTY. NICE ATMOSPHERIC RIVER WHICH SHOULD STAY
WELL OUT TO SEA.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
HIGH PRESSURE MOVING EAST ACROSS THE STATE WILL KEEP THE REGION
VFR OVERNIGHT AND FRIDAY.
A COLD FRONT WILL MOVE IN FROM THE NORTH EARLY THIS MORNING AND
COULD PRODUCE SOME SHOWERS AND REDUCED CIGS/VSBYS OVER THE NWRN
MOUNTAINS /KBFD/ FRIDAY MORNING...BUT WIDESPREAD REDUCTIONS ARE
NOT EXPECTED AS THE FRONT WILL NOT BE ESPECIALLY STRONG.
LIGHT...GENERALLY SWRLY WINDS THROUGH THE OVERNIGHT PERIOD WILL TURN
NWRLY BEHIND THE FRONT DURING THE DAY ON FRIDAY...WITH GUSTS OF 15
TO 25MPH EXPECTED AT MOST AIRFIELDS.
OUTLOOK...
SAT...NO SIG WX.
SUN...VFR...BUT MVFR POSSIBLE IN SCATTERED SHOWERS.
MON...MAINLY VFR...SOME LOWER CONDITIONS POSSIBLE WITH A COLD
FRONT AND SCATTERED SHOWERS.
TUE...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR
PAZ010>012-017>019-025>028-034>037-041-045-046-049>053-056>059-
063>066.
&&
$$
SYNOPSIS...GRUMM
NEAR TERM...GRUMM/FITZGERALD
SHORT TERM...GRUMM/FITZGERALD
LONG TERM...GRUMM/MARTIN
AVIATION...CERU/GARTNER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
219 AM EDT FRI OCT 12 2012
.SYNOPSIS...
A COLD FRONT WILL SWEEP THROUGH THE STATE EARLY TODAY. A MASSIVE
ANTICYCLONE WILL PRODUCE CLEAR CALM CONDITIONS FOR A WIDESPREAD
FROST SATURDAY. A MOISTURE PLUME AND WARMER AIR COULD BRING
SHOWERS SATURDAY NIGHT INTO SUNDAY.
A TROUGH OVER THE EASTERN UNITED STATES NEXT WEEK WILL SET UP TO
OUR WEST. A RELATIVELY DRY AND SEASONABLY WARM PERIOD OF WEATHER
IS EXPECTED FOR MOST OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
SATELLITE IMAGERY...IR AND 11-3.9 MICRON SHOW CLOUDS OVER
NORTHWESTERN PA. THE FIRST SURGES INTO WEST CENTRAL AREAS HAVE
DISSIPATED. MOST OF CENTRAL AND SOUTHERN PA ARE SPOT ON CLEAR.
THE CLEAR AREAS WITH DEW POINTS IN THE LOWER 30S HAVE PRODUCED
SOME REMARKABLE TEMPERATURE GRADIENTS. READINGS IN THE UPPER 20S
LOWER 30S. INCREDIBLE RANGE 29 IN PARTS OF CAMBRIA COUNTY AND 31
IN PARTS OF BLAIR COUNTY. MUCH COLDER THAN THE REGIONAL AIRPORTS.
WHERE KJST IS 39 AND KAOO IS 43 AND 44 AT KUNV. SOME PASSING
CLOUDS KEPT SOUTHERN AREAS IN 40S. TEMPERATURES SHOULD BEGIN TO
REBOUND IN EXTREME NORTHWEST WHERE CLOUDS MOVING IN.
THE RURAL NON-AIRPORT OBS REFLECT PATCHY FROST IN RURAL AREAS.
KCLE AND KBUF SHOW VERY LITTLE PRECIPITATION TO OUR WEST. 4KM NAM
AND HRRR ARE NOT VERY AGGRESSIVE WITH RAINFALL EITHER. LOWERED POPS
IN EARLY AM IN NW TO CHANCE.
THE 4KM NAM AT 0000 UTC AND RECENT 0,1,2, 3 UTC RAP DATA IMPLY
SHOWERS IN THE 10-12Z RANGE IN NW PA. BUT THE WEAK SHOWERS SEEM TO
FALL APART AS THEY MOVE INTO THE DRY AIR TO THE SOUTH AND EAST.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM SATURDAY/...
THE COLD FRONT WILL PUSH SOUTH ACROSS THE REGION BTWN 09Z-16Z WITH
THE CHANCE OF SOME LINGERING SHOWERS DURING THE FIRST PART OF THE
MORNING...ESPECIALLY OVER THE NWRN HALF OR SO OF THE STATE.
FRONTAL TIMING IS GOOD WITH THE 13KM RAP.
SHORT RANGE MODELS AGREE IN QUICKLY MOVING THE SFC HIGH AND LOW
PWAT AIR OVERHEAD BY AFTN...WHICH SHOULD BRING CLEARING SKIES.
ENSEMBLE MEAN 850 TEMPS ARE SUPPORTIVE OF HIGH TEMPS FROM JUST THE
M40S OVER THE N MTNS...TO THE U50S ACROSS THE LOWER SUSQ VALLEY. A
FAIRLY TIGHT PRES GRADIENT BEHIND FRONT WILL RESULT IN A BREEZY
DAY. BUFKIT SOUNDINGS SUPPORT FREQUENT GUSTS TO ARND 20KT BY AFTN.
RAP AND MOST GUIDANCE SUGGEST HIGHS RANGE FROM LOWER 40S NW TO
AROUND 60 EXTREME SOUTHEAST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
NOT MUCH CHANGE FROM RECENT DAYS.
FRIDAY NIGHT LIKELY TO RESULT IN WIDESPREAD FROST...FREEZE
ISSUES...AS A SPRAWLING 1032 MB HIGH PRESSURE BECOMES CENTERED
RIGHT OVER CENTRAL PENN BY 12Z SATURDAY. CLEAR SKIES...LIGHT WINDS...
LOW PW VALUES...AND INVERSION WILL ALLOW TEMPS TO DROP QUICKLY.
EXPANDED THE FREEZE WATCH TO COVER THE LOWER SUSQUEHANNA VLY...
EVEN IF MDT DOES NOT FREEZE...MOST AREAS WILL...AND EVEN THOSE
SPOTS THAT STAY A DEGREE OR TWO ABOVE FREEZING...WILL SEE SOME
FROST.
A MODERATING TREND IS IN STORE FOR SAT...BUT THE REAL MILD TEMPS
WILL ARRIVE SUNDAY INTO MONDAY...AS A STRONG LOW LIFTS NE ACROSS
THE LAKES. TEMPS WILL SPRING BACK INTO THE 60S. 850 MB TEMPS OVER
12 DEGREES C...AND A STRONG SW FLOW...WOULD SUPPORT TEMPS WELL
INTO THE 70S.
SOME SHOWERS ARE POSSIBLE WITH A WARM FRONT SATURDAY NIGHT AND
MORE SHOWERS WITH COLD FRONT LATER SUNDAY INTO MONDAY...HIGHEST
CHC ACROSS THE FAR NORTH. OVERALL...MUCH OF THE TIME WILL BE ON
THE DRY SIDE.
SLIGHTLY COOLER FOR LATER MONDAY INTO WED. SOME CHC OF SHOWERS
BY LATE THU. 12Z GFS HAS UPPER LVL TROUGH GOING NEGATIVE...
THUS SHOWERS MAY BE SLOW TO MOVE OUT.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
HIGH PRESSURE MOVING EAST ACROSS THE STATE WILL KEEP THE REGION
VFR OVERNIGHT AND FRIDAY.
A COLD FRONT WILL MOVE IN FROM THE NORTH EARLY THIS MORNING AND
COULD PRODUCE SOME SHOWERS AND REDUCED CIGS/VSBYS OVER THE NWRN
MOUNTAINS /KBFD/ FRIDAY MORNING...BUT WIDESPREAD REDUCTIONS ARE
NOT EXPECTED AS THE FRONT WILL NOT BE ESPECIALLY STRONG.
LIGHT...GENERALLY SWRLY WINDS THROUGH THE OVERNIGHT PERIOD WILL TURN
NWRLY BEHIND THE FRONT DURING THE DAY ON FRIDAY...WITH GUSTS OF 15
TO 25MPH EXPECTED AT MOST AIRFIELDS.
OUTLOOK...
SAT...NO SIG WX.
SUN...VFR...BUT MVFR POSSIBLE IN SCATTERED SHOWERS.
MON...MAINLY VFR...SOME LOWER CONDITIONS POSSIBLE WITH A COLD
FRONT AND SCATTERED SHOWERS.
TUE...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR
PAZ010>012-017>019-025>028-034>037-041-045-046-049>053-056>059-
063>066.
&&
$$
SYNOPSIS...GRUMM
NEAR TERM...GRUMM/FITZGERALD
SHORT TERM...GRUMM/FITZGERALD
LONG TERM...MARTIN
AVIATION...CERU/GARTNER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
158 AM EDT FRI OCT 12 2012
.SYNOPSIS...
A COLD FRONT...NEAR THE NORTH SHORE OF LAKE ERIE THIS EVENING...WILL
PUSH THROUGH CENTRAL PENNSYLVANIA FRIDAY MORNING.
A LARGE...COLD AREA OF HIGH PRESSURE WILL BUILD IN FRIDAY NIGHT
FROM THE NORTHERN PLAINS AND BECOME CENTERED OVER THE COMMONWEALTH
AROUND DAYBREAK SATURDAY...BRINGING THE THREAT OF A WIDESPREAD
FROST AND FREEZE TO THE AREA.
THE HIGH WILL MOVE OFF THE MID ATLANTIC COAST BY SUNDAY ALLOWING A
SOUTHWEST FLOW OF MILDER AIR TO RETURN TO THE REGION.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
SATELLITE IMAGERY...IR AND 11-3.9 MICRON SHOW CLOUDS OVER
NORTHWESTERN PA. THE FIRST SURGES INTO WEST CENTRAL AREAS HAVE
DISSIPATED. MOST OF CENTRAL AND SOUTHERN PA ARE SPOT ON CLEAR.
THE CLEAR AREAS WITH DEW POINTS IN THE LOWER 30S HAVE PRODUCED
SOME REMARKABLE TEMPERATURE GRADIENTS. READINGS IN THE UPPER 20S
LOWER 30S. INCREDIBLE RANGE 29 IN PARTS OF CAMBRIA COUNTY AND 31
IN PARTS OF BLAIR COUNTY. MUCH COLDER THAN THE REGIONAL AIRPORTS.
WHERE KJST IS 39 AND KAOO IS 43 AND 44 AT KUNV. SOME PASSING
CLOUDS KEPT SOUTHERN AREAS IN 40S. TEMPERATURES SHOULD BEGIN TO
REBOUND IN EXTREME NORTHWEST WHERE CLOUDS MOVING IN.
THE RURAL NON-AIRPORT OBS REFLECT PATCHY FROST IN RURAL AREAS.
KCLE AND KBUF SHOW VERY LITTLE PRECIPITATION TO OUR WEST. 4KM NAM
AND HRRR ARE NOT VERY AGGRESSIVE WITH RAINFALL EITHER. LOWERED POPS
IN EARLY AM IN NW TO CHANCE.
THE 4KM NAM AT 0000 UTC AND RECENT 0,1,2, 3 UTC RAP DATA IMPLY
SHOWERS IN THE 10-12Z RANGE IN NW PA. BUT THE WEAK SHOWERS SEEM TO
FALL APART AS THEY MOVE INTO THE DRY AIR TO THE SOUTH AND EAST.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM SATURDAY/...
THE COLD FRONT WILL PUSH SOUTH ACROSS THE REGION BTWN 09Z-16Z WITH
THE CHANCE OF SOME LINGERING SHOWERS DURING THE FIRST PART OF THE
MORNING...ESPECIALLY OVER THE NWRN HALF OR SO OF THE STATE.
FRONTAL TIMING IS GOOD WITH THE 13KM RAP.
SHORT RANGE MODELS AGREE IN QUICKLY MOVING THE SFC HIGH AND LOW
PWAT AIR OVERHEAD BY AFTN...WHICH SHOULD BRING CLEARING SKIES.
ENSEMBLE MEAN 850 TEMPS ARE SUPPORTIVE OF HIGH TEMPS FROM JUST THE
M40S OVER THE N MTNS...TO THE U50S ACROSS THE LOWER SUSQ VALLEY. A
FAIRLY TIGHT PRES GRADIENT BEHIND FRONT WILL RESULT IN A BREEZY
DAY. BUFKIT SOUNDINGS SUPPORT FREQUENT GUSTS TO ARND 20KT BY AFTN.
RAP AND MOST GUIDANCE SUGGEST HIGHS RANGE FROM LOWER 40S NW TO
AROUND 60 EXTREME SOUTHEAST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
NOT MUCH CHANGE FROM RECENT DAYS.
FRIDAY NIGHT LIKELY TO RESULT IN WIDESPREAD FROST...FREEZE
ISSUES...AS A SPRAWLING 1032 MB HIGH PRESSURE BECOMES CENTERED
RIGHT OVER CENTRAL PENN BY 12Z SATURDAY. CLEAR SKIES...LIGHT WINDS...
LOW PW VALUES...AND INVERSION WILL ALLOW TEMPS TO DROP QUICKLY.
EXPANDED THE FREEZE WATCH TO COVER THE LOWER SUSQUEHANNA VLY...
EVEN IF MDT DOES NOT FREEZE...MOST AREAS WILL...AND EVEN THOSE
SPOTS THAT STAY A DEGREE OR TWO ABOVE FREEZING...WILL SEE SOME
FROST.
A MODERATING TREND IS IN STORE FOR SAT...BUT THE REAL MILD TEMPS
WILL ARRIVE SUNDAY INTO MONDAY...AS A STRONG LOW LIFTS NE ACROSS
THE LAKES. TEMPS WILL SPRING BACK INTO THE 60S. 850 MB TEMPS OVER
12 DEGREES C...AND A STRONG SW FLOW...WOULD SUPPORT TEMPS WELL
INTO THE 70S.
SOME SHOWERS ARE POSSIBLE WITH A WARM FRONT SATURDAY NIGHT AND
MORE SHOWERS WITH COLD FRONT LATER SUNDAY INTO MONDAY...HIGHEST
CHC ACROSS THE FAR NORTH. OVERALL...MUCH OF THE TIME WILL BE ON
THE DRY SIDE.
SLIGHTLY COOLER FOR LATER MONDAY INTO WED. SOME CHC OF SHOWERS
BY LATE THU. 12Z GFS HAS UPPER LVL TROUGH GOING NEGATIVE...
THUS SHOWERS MAY BE SLOW TO MOVE OUT.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
HIGH PRESSURE MOVING EAST ACROSS THE STATE WILL KEEP THE REGION
VFR OVERNIGHT AND FRIDAY.
A COLD FRONT WILL MOVE IN FROM THE NORTH EARLY THIS MORNING AND
COULD PRODUCE SOME SHOWERS AND REDUCED CIGS/VSBYS OVER THE NWRN
MOUNTAINS /KBFD/ FRIDAY MORNING...BUT WIDESPREAD REDUCTIONS ARE
NOT EXPECTED AS THE FRONT WILL NOT BE ESPECIALLY STRONG.
LIGHT...GENERALLY SWRLY WINDS THROUGH THE OVERNIGHT PERIOD WILL TURN
NWRLY BEHIND THE FRONT DURING THE DAY ON FRIDAY...WITH GUSTS OF 15
TO 25MPH EXPECTED AT MOST AIRFIELDS.
OUTLOOK...
SAT...NO SIG WX.
SUN...VFR...BUT MVFR POSSIBLE IN SCATTERED SHOWERS.
MON...MAINLY VFR...SOME LOWER CONDITIONS POSSIBLE WITH A COLD
FRONT AND SCATTERED SHOWERS.
TUE...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR
PAZ010>012-017>019-025>028-034>037-041-045-046-049>053-056>059-
063>066.
&&
$$
SYNOPSIS...FITZGERALD/LA CORTE
NEAR TERM...GRUMM/FITZGERALD
SHORT TERM...GRUMM/FITZGERALD
LONG TERM...MARTIN
AVIATION...CERU/GARTNER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
107 AM EDT FRI OCT 12 2012
.SYNOPSIS...
A COLD FRONT...NEAR THE NORTH SHORE OF LAKE ERIE THIS EVENING...WILL
PUSH THROUGH CENTRAL PENNSYLVANIA FRIDAY MORNING.
A LARGE...COLD AREA OF HIGH PRESSURE WILL BUILD IN FRIDAY NIGHT
FROM THE NORTHERN PLAINS AND BECOME CENTERED OVER THE COMMONWEALTH
AROUND DAYBREAK SATURDAY...BRINGING THE THREAT OF A WIDESPREAD
FROST AND FREEZE TO THE AREA.
THE HIGH WILL MOVE OFF THE MID ATLANTIC COAST BY SUNDAY ALLOWING A
SOUTHWEST FLOW OF MILDER AIR TO RETURN TO THE REGION.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
SATELLITE IMAGERY...IR AND 11-3.9 MICRON SHOW CLOUDS OVER
NORTHWESTERN PA. THE FIRST SURGES INTO WEST CENTRAL AREAS HAVE
DISSIPATED. MOST OF CENTRAL AND SOUTHERN PA ARE SPOT ON CLEAR.
THE CLEAR AREAS WITH DEW POINTS IN THE LOWER 30S HAVE PRODUCED
SOME REMARKABLE TEMPERATURE GRADIENTS. READINGS IN THE UPPER 20S
LOWER 30S. INCREDIBLE RANGE 29 IN PARTS OF CAMBRIA COUNTY AND 31
IN PARTS OF BLAIR COUNTY. MUCH COLDER THAN THE REGIONAL AIRPORTS.
WHERE KJST IS 39 AND KAOO IS 43 AND 44 AT KUNV. SOME PASSING
CLOUDS KEPT SOUTHERN AREAS IN 40S. TEMPERATURES SHOULD BEGIN TO
REBOUND IN EXTREME NORTHWEST WHERE CLOUDS MOVING IN.
THE RURAL NON-AIRPORT OBS REFLECT PATCHY FROST IN RURAL AREAS.
KCLE AND KBUF SHOW VERY LITTLE PRECIPITATION TO OUR WEST. 4KM NAM
AND HRRR ARE NOT VERY AGGRESSIVE WITH RAINFALL EITHER. LOWERED POPS
IN EARLY AM IN NW TO CHANCE.
THE 4KM NAM AT 0000 UTC AND RECENT 0,1,2, 3 UTC RAP DATA IMPLY
SHOWERS IN THE 10-12Z RANGE IN NW PA. BUT THE WEAK SHOWERS SEEM TO
FALL APART AS THEY MOVE INTO THE DRY AIR TO THE SOUTH AND EAST.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM SATURDAY/...
THE COLD FRONT WILL PUSH SOUTH ACROSS THE REGION BTWN 09Z-16Z WITH
THE CHANCE OF SOME LINGERING SHOWERS DURING THE FIRST PART OF THE
MORNING...ESPECIALLY OVER THE NWRN HALF OR SO OF THE STATE.
FRONTAL TIMING IS GOOD WITH THE 13KM RAP.
SHORT RANGE MODELS AGREE IN QUICKLY MOVING THE SFC HIGH AND LOW
PWAT AIR OVERHEAD BY AFTN...WHICH SHOULD BRING CLEARING SKIES.
ENSEMBLE MEAN 850 TEMPS ARE SUPPORTIVE OF HIGH TEMPS FROM JUST THE
M40S OVER THE N MTNS...TO THE U50S ACROSS THE LOWER SUSQ VALLEY. A
FAIRLY TIGHT PRES GRADIENT BEHIND FRONT WILL RESULT IN A BREEZY
DAY. BUFKIT SOUNDINGS SUPPORT FREQUENT GUSTS TO ARND 20KT BY AFTN.
RAP AND MOST GUIDANCE SUGGEST HIGHS RANGE FROM LOWER 40S NW TO
AROUND 60 EXTREME SOUTHEAST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
NOT MUCH CHANGE FROM RECENT DAYS.
FRIDAY NIGHT LIKELY TO RESULT IN WIDESPREAD FROST...FREEZE
ISSUES...AS A SPRAWLING 1032 MB HIGH PRESSURE BECOMES CENTERED
RIGHT OVER CENTRAL PENN BY 12Z SATURDAY. CLEAR SKIES...LIGHT WINDS...
LOW PW VALUES...AND INVERSION WILL ALLOW TEMPS TO DROP QUICKLY.
EXPANDED THE FREEZE WATCH TO COVER THE LOWER SUSQUEHANNA VLY...
EVEN IF MDT DOES NOT FREEZE...MOST AREAS WILL...AND EVEN THOSE
SPOTS THAT STAY A DEGREE OR TWO ABOVE FREEZING...WILL SEE SOME
FROST.
A MODERATING TREND IS IN STORE FOR SAT...BUT THE REAL MILD TEMPS
WILL ARRIVE SUNDAY INTO MONDAY...AS A STRONG LOW LIFTS NE ACROSS
THE LAKES. TEMPS WILL SPRING BACK INTO THE 60S. 850 MB TEMPS OVER
12 DEGREES C...AND A STRONG SW FLOW...WOULD SUPPORT TEMPS WELL
INTO THE 70S.
SOME SHOWERS ARE POSSIBLE WITH A WARM FRONT SATURDAY NIGHT AND
MORE SHOWERS WITH COLD FRONT LATER SUNDAY INTO MONDAY...HIGHEST
CHC ACROSS THE FAR NORTH. OVERALL...MUCH OF THE TIME WILL BE ON
THE DRY SIDE.
SLIGHTLY COOLER FOR LATER MONDAY INTO WED. SOME CHC OF SHOWERS
BY LATE THU. 12Z GFS HAS UPPER LVL TROUGH GOING NEGATIVE...
THUS SHOWERS MAY BE SLOW TO MOVE OUT.
&&
.AVIATION /05Z FRIDAY THROUGH TUESDAY/...
HIGH PRESSURE MOVING EAST ACROSS THE STATE WILL KEEP THE REGION
VFR OVERNIGHT AND FRIDAY.
A COLD FRONT WILL MOVE IN FROM THE NORTH LATE TONIGHT AND COULD
PRODUCE SOME SHOWERS AND REDUCED CIGS/VSBYS OVER THE NWRN
MOUNTAINS /KBFD/ FRIDAY MORNING...BUT WIDESPREAD REDUCTIONS ARE
NOT EXPECTED AS THE FRONT WILL NOT BE ESPECIALLY STRONG.
LIGHT...GENERALLY SWRLY WINDS THROUGH THE OVERNIGHT WILL TURN
NWRLY BEHIND THE FRONT DURING THE DAY ON FRIDAY...WITH GUSTS OF
15 TO 25MPH EXPECTED AT MOST AIRFIELDS.
OUTLOOK...
SAT...NO SIG WX.
SUN...VFR...BUT MVFR POSSIBLE IN SCATTERED SHOWERS.
MON...MAINLY VFR...SOME LOWER CONDITIONS POSSIBLE WITH A COLD
FRONT AND SCATTERED SHOWERS.
TUE...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR
PAZ010>012-017>019-025>028-034>037-041-045-046-049>053-056>059-
063>066.
&&
$$
SYNOPSIS...FITZGERALD/LA CORTE
NEAR TERM...GRUMM/FITZGERALD
SHORT TERM...GRUMM/FITZGERALD
LONG TERM...MARTIN
AVIATION...GARTNER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
104 AM EDT FRI OCT 12 2012
.SYNOPSIS...
A COLD FRONT...NEAR THE NORTH SHORE OF LAKE ERIE THIS EVENING...WILL
PUSH THROUGH CENTRAL PENNSYLVANIA FRIDAY MORNING.
A LARGE...COLD AREA OF HIGH PRESSURE WILL BUILD IN FRIDAY NIGHT
FROM THE NORTHERN PLAINS AND BECOME CENTERED OVER THE COMMONWEALTH
AROUND DAYBREAK SATURDAY...BRINGING THE THREAT OF A WIDESPREAD
FROST AND FREEZE TO THE AREA.
THE HIGH WILL MOVE OFF THE MID ATLANTIC COAST BY SUNDAY ALLOWING A
SOUTHWEST FLOW OF MILDER AIR TO RETURN TO THE REGION.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
SATELLITE IMAGERY...IR AND 11-3.9 MICRON SHOW CLOUDS OVER
NORTHWESTERN PA. THE FIRST SURGES INTO WEST CENTRAL AREAS HAVE
DISSIPATED. MOST OF CENTRAL AND SOUTHERN PA ARE SPOT ON CLEAR.
THE CLEAR AREAS WITH DEW POINTS IN THE LOWER 30S HAVE PRODUCED
SOME REMARKABLE TEMPERATURE GRADIENTS. READINGS IN THE UPPER 20S
LOWER 30S. INCREDIBLE RANGE 29 KJST AND 32 AT KAOO 44 AT STATE
COLLEGE. SOME PASSING CLOUDS KEPT SOUTHERN AREAS IN 40S.
TEMPERATURES SHOULD BEGIN TO REBOUND IN EXTREME NORTHWEST WHERE
CLOUDS MOVING IN.
KCLE AND KBUF SHOW VERY LITTLE PRECIPITATION TO OUR WEST. 4KM NAM
AND HRRR ARE NOT VERY AGGRESSIVE WITH RAINFALL EITHER. LOWERED POPS
IN EARLY AM IN NW TO CHANCE.
THE 4KM NAM AT 0000 UTC AND RECENT 0,1,2, 3 UTC RAP DATA IMPLY
SHOWERS IN THE 10-12Z RANGE IN NW PA. BUT THE WEAK SHOWERS SEEM TO
FALL APART AS THEY MOVE INTO THE DRY AIR TO THE SOUTH AND EAST.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM SATURDAY/...
THE COLD FRONT WILL PUSH SOUTH ACROSS THE REGION BTWN 09Z-16Z WITH
THE CHANCE OF SOME LINGERING SHOWERS DURING THE FIRST PART OF THE
MORNING...ESPECIALLY OVER THE NWRN HALF OR SO OF THE STATE.
FRONTAL TIMING IS GOOD WITH THE 13KM RAP.
SHORT RANGE MODELS AGREE IN QUICKLY MOVING THE SFC HIGH AND LOW
PWAT AIR OVERHEAD BY AFTN...WHICH SHOULD BRING CLEARING SKIES.
ENSEMBLE MEAN 850 TEMPS ARE SUPPORTIVE OF HIGH TEMPS FROM JUST THE
M40S OVER THE N MTNS...TO THE U50S ACROSS THE LOWER SUSQ VALLEY. A
FAIRLY TIGHT PRES GRADIENT BEHIND FRONT WILL RESULT IN A BREEZY
DAY. BUFKIT SOUNDINGS SUPPORT FREQUENT GUSTS TO ARND 20KT BY AFTN.
RAP AND MOST GUIDANCE SUGGEST HIGHS RANGE FROM LOWER 40S NW TO
AROUND 60 EXTREME SOUTHEAST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
NOT MUCH CHANGE FROM RECENT DAYS.
FRIDAY NIGHT LIKELY TO RESULT IN WIDESPREAD FROST...FREEZE
ISSUES...AS A SPRAWLING 1032 MB HIGH PRESSURE BECOMES CENTERED
RIGHT OVER CENTRAL PENN BY 12Z SATURDAY. CLEAR SKIES...LIGHT WINDS...
LOW PW VALUES...AND INVERSION WILL ALLOW TEMPS TO DROP QUICKLY.
EXPANDED THE FREEZE WATCH TO COVER THE LOWER SUSQUEHANNA VLY...
EVEN IF MDT DOES NOT FREEZE...MOST AREAS WILL...AND EVEN THOSE
SPOTS THAT STAY A DEGREE OR TWO ABOVE FREEZING...WILL SEE SOME
FROST.
A MODERATING TREND IS IN STORE FOR SAT...BUT THE REAL MILD TEMPS
WILL ARRIVE SUNDAY INTO MONDAY...AS A STRONG LOW LIFTS NE ACROSS
THE LAKES. TEMPS WILL SPRING BACK INTO THE 60S. 850 MB TEMPS OVER
12 DEGREES C...AND A STRONG SW FLOW...WOULD SUPPORT TEMPS WELL
INTO THE 70S.
SOME SHOWERS ARE POSSIBLE WITH A WARM FRONT SATURDAY NIGHT AND
MORE SHOWERS WITH COLD FRONT LATER SUNDAY INTO MONDAY...HIGHEST
CHC ACROSS THE FAR NORTH. OVERALL...MUCH OF THE TIME WILL BE ON
THE DRY SIDE.
SLIGHTLY COOLER FOR LATER MONDAY INTO WED. SOME CHC OF SHOWERS
BY LATE THU. 12Z GFS HAS UPPER LVL TROUGH GOING NEGATIVE...
THUS SHOWERS MAY BE SLOW TO MOVE OUT.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
HIGH PRESSURE MOVING EAST ACROSS THE STATE WILL KEEP THE REGION
VFR OVERNIGHT AND FRIDAY.
A COLD FRONT WILL MOVE IN FROM THE NORTH LATE TONIGHT AND COULD
PRODUCE SOME SHOWERS AND REDUCED CIGS/VSBYS OVER THE NWRN
MOUNTAINS /KBFD/ FRIDAY MORNING...BUT WIDESPREAD REDUCTIONS ARE
NOT EXPECTED AS THE FRONT WILL NOT BE ESPECIALLY STRONG.
LIGHT...GENERALLY SWRLY WINDS THROUGH THE OVERNIGHT WILL TURN
NWRLY BEHIND THE FRONT DURING THE DAY ON FRIDAY...WITH GUSTS OF
15 TO 25MPH EXPECTED AT MOST AIRFIELDS.
OUTLOOK...
SAT...NO SIG WX.
SUN...VFR...BUT MVFR POSSIBLE IN SCATTERED SHOWERS.
MON...MAINLY VFR...SOME LOWER CONDITIONS POSSIBLE WITH A COLD
FRONT AND SCATTERED SHOWERS.
TUE...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR
PAZ010>012-017>019-025>028-034>037-041-045-046-049>053-056>059-
063>066.
&&
$$
SYNOPSIS...FITZGERALD/LA CORTE
NEAR TERM...GRUMM/FITZGERALD
SHORT TERM...GRUMM/FITZGERALD
LONG TERM...MARTIN
AVIATION...GARTNER
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1147 PM CDT THU OCT 11 2012
.AVIATION...
WINDS HAVE DECREASED TO NEAR 5 KTS LATE THIS EVENING...WITH VFR
CONDITIONS PREVAILING FOR THE NEXT SEVERAL HOURS. TOWARDS THE
MORNING HOURS...LIGHT WINDS WITH DEW POINTS IN THE LOW TO MID 60S
WILL HELP LOWER CIGS TO THE LOW END MVFR CATEGORY UNTIL AROUND
15Z. MAIN HAZARD IN THE TAF PERIOD WILL BE THE POSSIBILITY FOR
STRONG TO SEVERE CONVECTION TOMORROW AFTERNOON...WITH THE PRIMARY
THREAT BEING HAIL...THOUGH SOME THUNDERSTORMS MAY HAVE THE
POTENTIAL TO PRODUCE HIGH WIND GUSTS IN EXCESS OF 40 KTS. GRADIENT
WINDS DURING THE AFTERNOON WILL BE GUSTY...WITH SUSTAINED WINDS
NEAR 14 KTS AND GUSTS UP TO 25 KTS.
&&
.PREV DISCUSSION... /ISSUED 959 PM CDT THU OCT 11 2012/
UPDATE...
9 PM SATELLITE AND RADAR DATA SHOW A BATCH OF SHOWERS AND ISOLD
TSTMS MOVING NEWD FROM EASTERN NM INTO THE WESTERN TX
PANHANDLE...BYPASSING OUR CWA EXCEPT PERHAPS FOR PARMER COUNTY.
SFC OBS SHOW A FRONT JUST MOVING INTO THE NRN TX PANHANDLE. AS THE
FRONT MOVES SOUTH...THE CURRENT ACTIVITY MAY GET A BIT OF A BOOST
FROM LIFT ALONG THE FRONT. MOST OF THIS ACTIVITY SHOULD REMAIN TO
OUR NORTH...BUT COULD SINK SWD INTO OUR NRN ZONES AFTER MIDNIGHT.
THE HRRR HAS BEEN ADVERTISING SCT TSTMS MOVING INTO OUR SW ZONES
AFTER MIDNIGHT FOR SEVERAL RUNS NOW...BUT IT/S DEPICTION OF CURRENT
ACTIVITY IN SE NM AND FAR WEST TEXAS SEEMS OVERDONE...LOWERING
CONFIDENCE IN IT/S FORECAST.
THE 0Z NAM HAS ARRIVED. IT HINTS THAT THERE COULD BE TWO ROUNDS OF
STORMS. THE FIRST ROUND OF STORMS FIRING OFF THE HIER TERRAIN OF
NM BY EARLY AFTERNOON...EVENTUALLY PASSING THROUGH MOST OF THE
CWA FRIDAY EVENING. THEN ANOTHER LINE OF STORMS LATE FRIDAY
NIGHT/SAT MORNING FORCED ALONG A PACIFIC-TYPE FRONT SWEEPING
ACROSS THE FA. FCST SNDGS STILL INDICATE POTENTIAL FOR SEVERE
WEATHER FRIDAY AFTERNOON AND EVENING. THE SOUNDING AT LUBBOCK
SUGGESTS THAT SKIES COULD VERY WELL PARTIALLY CLEAR OUT ALLOWING
SBCAPES TO RISE TO NEAR 2000 J/KG AND TEMPS TO SUFFICIENTLY WARM
FOR SURFACE-BASED CONVECTION. SHEAR APPEARS FAIRLY UNIDRECTIONAL
AT LUBBOCK...BUT WILL LIKELY EXHIBIT MORE TURNING ACROSS THE FAR
SRN TX PANHANDLE.
NO CHANGES IN FCST FOR NOW...WILL WAIT AND SEE WHAT THE 0Z GFS
BRINGS.
PREV DISCUSSION... /ISSUED 633 PM CDT THU OCT 11 2012/
AVIATION...
VFR CONDITIONS WILL PREVAIL AT BOTH TERMINALS DURING THE OVERNIGHT
HOURS. VIS SAT SHOWS A CLUSTER OF CLOUDS BEGINING TO MOVE INTO THE
KCDS AREA...WHICH SHOULD BRING THE CIGS FROM FEW TO BKN
SHORTLY...BUT WILL REMAIN IN THE VFR CATEGORY. ISOLATED TO
SCATTERED CONVECTION WILL MOVE INTO THE AREA LATE THIS EVENING
WHICH COULD IMPACT EITHER TERMINAL. AND STORMS AFFECTING A
TERMINAL COULD BRING CIGS TO MVFR...IFR AT WORST...FOR A SHORT
PERIOD OF TIME. WINDS WILL ALSO BE GUSTY TONIGHT WITH GUSTS TO 25
KTS. CIGS WILL BECOME LOW END MVFR TOWARDS MORNING IN RESPONSE TO
ABUDUNT LOW LEVEL MOISTURE MOVING INTO THE AREA. BIG AREA OF
CONCERN WILL BE TOMORROW AFTERNOON WITH THE POSSIBILITY OF STRONG
TO SEVERE THUNDERSTORMS AFFECTING THE FA. HAIL WILL BE THE PRIMARY
THREAT FOR THUNDERSTORMS...BUT MAY ALSO HAVE SEVERE WIND GUSTS AS
WELL.
PREV DISCUSSION... /ISSUED 350 PM CDT THU OCT 11 2012/
SHORT TERM...
ONGOING CONVECTION ORIGINATING DURING THE LATE AFTERNOON/EARLY
EVENING ACROSS THE EXTREME SOUTHWESTERN TEXAS PANHANDLE WILL PUSH
EAST OVERNIGHT AND LOSE INTENSITY AS IT TRIES TO MOVE INTO THE
SOUTHERN HALF OF THE ROLLING PLAINS. THIS IS DUE TO A MID-LEVEL
SHORTWAVE TROUGH INTERACTING WITH RICH BOUNDARY LAYER MOISTURE AS
EVIDENCED BY DEWPOINTS IN THE LOW 60S. DEEP LAYER INSTABILITY WILL
BE HIGHEST NEAR THE NEW MEXICO STATE LINE AS GREATER MIXING THIS
AFTERNOON SOMEWHAT ALLEVIATES A SHALLOW NEAR-SURFACE COLD POOL WHICH
WILL INHIBIT CONVECTION FARTHER SOUTH AND EAST. A 35 KNOT LOW-LEVEL
JET WILL STRENGTHEN WIND FIELDS AND PROMOTE THE CHANCE FOR CONTINUING
CONVECTION THROUGHOUT THE NIGHT. AREAS ACROSS THE SOUTHEASTERN
ROLLING PLAINS WILL SEE SOME PATCHY FOG FOR A FEW HOURS TOMORROW
MORNING NEAR SUNRISE AS ABUNDANT MOISTURE REMAINS TRAPPED IN A
FAIRLY STABLE NOCTURNAL BOUNDARY LAYER.
A MID-UPPER LEVEL LOW PRESSURE CENTER WILL EJECT NORTHEASTWARD FROM
OFF THE SOUTHERN CALIFORNIA COAST AND MOVE TOWARD THE ROCKY MOUNTAIN
REGION AND CENTRAL GREAT PLAINS. THIS FEATURE WILL BE THE FOCUS FOR
A REGIONAL SEVERE WEATHER OUTBREAK WHICH WILL ENCOMPASS WEST TEXAS.
THE MAIN CONCERN FOR ORGANIZED AND WIDESPREAD SEVERE CONVECTION
FRIDAY AFTERNOON/EVENING WILL BE INSTABILITY DUE TO CLOUD COVER AND
REMNANTS OF MORNING STORMS. DYNAMICS WILL BE FAVORABLE FOR
LARGE-SCALE ASCENT ACROSS THE ENTIRE AREA...WITH THE BEST LIFT
OCCURRING NORTH AND WEST AND DECREASING IN INTENSITY TO THE SOUTH
AND EAST.
AS HEIGHTS FALL AHEAD OF THIS LOW BY MID AFTERNOON...DISCRETE CELLS
WILL HAVE THE INITIAL CHANCE TO COMMENCE. BACKING LOW-LEVEL WINDS
AND INCREASINGLY CLOCKWISE-CURVED HODOGRAPHS WILL SUPPORT THE CHANCE
FOR AN ISOLATED TORNADO. WHILE A FEW SURFACE-BASED STORMS MAY BE
ABLE TO GENERATE TO THE WEST NEAR THE NEW MEXICO STATE LINE...WHERE
BETTER MIXING WILL TAKE PLACE...A RESIDUAL COOLER AND MORE STABLE
BOUNDARY LAYER WILL LIKELY CAUSE STORMS TO BE ELEVATED IN NATURE.
THIS WILL LEAD TO PRIMARILY A HAIL THREAT AS CONVECTIVE WIND GUSTS
MAY STRUGGLE TO REACH THE SURFACE. HEAVY RAIN WILL ALSO BE A
POSSIBILITY WHERE STORMS TRAIN.
LONG TERM...
CONVECTION IS EXPECTED TO CONTINUE THROUGHOUT THE EVENING AND
OVERNIGHT HOURS FRIDAY INTO SATURDAY. THE MOST WIDESPREAD COVERAGE
IS EXPECTED TO BE BETWEEN 00Z AND 06Z. MAXIMUM LIFT FROM THE CLOSED
LOW/TROUGH CONTINUES TO BE PROGGED NORTH OF THE AREA. THE BEST
THERMODYNAMIC PARAMETERS WILL BE CENTERED OVER THE SOUTHWESTERN
TEXAS PANHANDLE AND VERY IMPRESSIVE FOR OCTOBER STANDARDS. AS CLOUDS
CLEAR OUT...CAPES IN EXCESS OF 1000 J/KG WILL BE SEEN NEAR THE
TEXAS...NEW MEXICO STATE LINE. INSTABILITY WILL BE LESS AND CIN WILL
BE HIGHER EAST OF HERE WITH CLOUD COVER PERSISTING FOR A GOOD
PORTION OF THE DAYTIME. THE BEST LOW LEVEL HELICITY AND SHEAR
VECTORS WILL AGAIN BE LOCATED OVER THE SOUTHWESTERN TEXAS PANHANDLE.
MODEL HODOGRAPHS DO SHOW SOME LOW LEVEL TURNING BUT IS STILL RATHER
WEAK. THOUGH IT IS WEAK...IT IS ENOUGH TO NOT BE IGNORED FOR A
TORNADO THREAT. HOWEVER...ABOVE THIS LOW LAYER...STRONG SHEAR WILL
EXIST LENDING TO ORGANIZED SEVERE CONVECTION. LARGE HAIL IS STILL
THE PRIMARY THREAT FROM THIS CONVECTION. WOULD STILL EXPECT MORE
DISCRETE CELLS OVER THE SOUTHWESTERN PANHANDLE AND SOUTH PLAINS AND
MORE LINEAR FEATURES FARTHER NORTH IN THE WESTERN AND CENTRAL
PANHANDLE. STORM CHANCES WILL SHIFT EAST DURING THE EVENING AND
OVERNIGHT WITH THE DEVELOPMENT OF A LOW LEVEL JET. THIS LLJ WILL BE
MAXIMIZED OVER THE ROLLING PLAINS AT IMPRESSIVE SPEEDS NEAR 50KT.
ELEVATED INSTABILITY WILL ALSO CONTINUE THROUGH THE NIGHT WITH THIS
LLJ.
A CLOSED LOW SOLUTION PERSISTING INTO SATURDAY APPEARS MORE
PLAUSIBLE WITH THE LATEST MODEL RUNS. UPPER LEVEL LIFT FROM THIS LOW
WILL BE TRAILING OVER THE ROLLING PLAINS SATURDAY MORNING AND
AFTERNOON. STORM REDEVELOPMENT WILL BE POSSIBLE OVER THIS AREA
DURING THIS TIME PERIOD. A STRONG UPPER LEVEL JET WILL BE MOVING
DIRECTLY OVERHEAD ON SATURDAY. THIS LIFT MAY OBTAIN SOME ASSISTANCE
FROM A PACIFIC FRONT SWEEPING INTO THE ROLLING PLAINS. THIS FRONT IS
EXPECTED TO SIGNIFICANTLY SLOW OR EVEN STALL OUT BY THE AFTERNOON.
SUBSIDENCE AND DRYING OUT WILL OCCUR ON SATURDAY ACROSS THE REST OF
THE AREA AND THEN THROUGH THE ROLLING PLAINS ON SUNDAY. A COLD FRONT
IS STILL EXPECTED BY LATE TUESDAY OR WEDNESDAY. HOWEVER THE GFS IS
NOTABLY STRONGER WITH THIS FRONT THAN THE ECMWF. JDV
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 78 58 75 50 73 / 30 50 70 80 0
TULIA 78 58 76 58 75 / 20 40 50 70 0
PLAINVIEW 79 58 77 58 77 / 20 40 50 70 0
LEVELLAND 80 59 78 57 77 / 20 30 60 60 0
LUBBOCK 79 61 78 62 78 / 20 30 50 60 0
DENVER CITY 80 59 80 58 77 / 20 30 60 50 0
BROWNFIELD 79 59 79 59 78 / 20 30 60 60 0
CHILDRESS 81 64 83 66 82 / 10 30 30 60 20
SPUR 80 65 82 64 80 / 10 30 20 60 20
ASPERMONT 82 66 84 68 82 / 10 10 20 50 30
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
51/33/51
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
348 AM CDT FRI OCT 12 2012
.UPDATE...
REGARDING THE LATEST 12.06Z NAM HANDLING OF THE SATURDAY INTO SUNDAY
SYSTEM...THE MODEL IS DEFINITELY AN OUTLIER SHOWING A MUCH SLOWER
PROGRESS EJECTING THE UPPER LOW COMPARED TO ALL OTHER 12.00Z
GUIDANCE. THE REASON IT IS SLOWER IS THAT THE LOW MERGES WITH THE
POTENT SHORTWAVE ROTATING AROUND IT AS THE SHORTWAVE CROSSES NEW
MEXICO INTO THE OKLAHOMA AND TEXAS PANHANDLES. WILL NOT MAKE ANY
CHANGES TO THE FORECAST BECAUSE OF THIS MODEL....BUT...SHOULD IT
VERIFY THE SEVERE RISK FOR SATURDAY AFTERNOON AND EVENING WOULD BE
ELIMINATED. IN ADDITION...THE NORTHWEST HALF OF THE FORECAST AREA
WOULD RECEIVE A LOT LESS RAIN. OF INTEREST...THE 08.12Z CANADIAN RUN
WAS ALMOST IDENTICAL TO THE LATEST 12.06Z NAM. SOME SIMILARITIES TOO
WITH THE 12.00Z CANADIAN TO THE 12.06Z NAM...BUT THE CANADIAN IS
FASTER AND CLOSER TO OTHER GUIDANCE SUCH AS THE GFS/ECMWF/UKMET.
&&
.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
258 AM CDT FRI OCT 12 2012
MAIN FORECAST CONCERN IS ON SEVERE WEATHER POTENTIAL SATURDAY INTO
SATURDAY NIGHT.
CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A SPLIT FLOW PATTERN ACROSS NORTH AMERICA. IN THE NORTHERN
STREAM...WEAK RIDGING WAS NOTED OVER THE NORTHERN U.S. ROCKIES AND
THEN DOWNSTREAM TROUGHING OVER THE GREAT LAKES. IN THE SOUTHERN
STREAM...AN UPPER LOW WAS OVER SOUTHERN CALIFORNIA WITH RIDGING
BUILDING UP AHEAD OF IT ACROSS THE CENTRAL AND SOUTHERN PLAINS. OVER
THE FORECAST AREA...SATELLITE IMAGERY SHOWED SKIES HAVE CLEARED OUT
THANKS TO SUBSIDENCE AND DRYING IN THE WAKE OF THE GREAT LAKES
TROUGHING. ALSO REFLECTED OF THE SUBSIDENCE IS A 1030MB SURFACE HIGH
CENTERED NEAR MINNEAPOLIS. PRECIPITABLE WATER VALUES WERE QUITE DRY
ON THE 00Z MPX SOUNDING...0.17 INCHES OR 30 PERCENT NORMAL. SURFACE
DEWPOINTS ALSO REFLECTIVE OF THE DRYING...DOWN IN THE TEENS TO LOWER
20S. DECENT AMOUNT OF COLD AIR ACCOMPANYING THE SURFACE HIGH WITH
850MB TEMPS THAT DROPPED TO -4C AT MPX AT 00Z COMPARED TO +3C 12
HOURS EARLIER. TO THE SOUTH...A STATIONARY FRONTAL BOUNDARY WAS
POSITIONED FROM OKLAHOMA INTO THE OHIO RIVER VALLEY. SOUTH OF THIS
FRONT...PLENTIFUL MOISTURE WAS NOTED WITH SURFACE DEWPOINTS IN THE
MID 60S TO LOWER 70S ACROSS OKLAHOMA AND MUCH OF TEXAS. 00Z FORT
WORTH SOUNDING HAD A PRECIPITABLE WATER VALUE OF 1.6 INCHES OR 176
PERCENT OF NORMAL. 850MB PROFILER AND VWP DATA CURRENTLY SHOWS MUCH
OF THIS MOISTURE BEING ADVECTED INTO AND ALONG THE STATIONARY
FRONTAL BOUNDARY.
TODAY AND TONIGHT...MAJOR CHANGES LOOK TO OCCUR IN THE WEATHER
PATTERN ACROSS THE FORECAST AREA DURING THIS TIME. THE UPPER LOW IN
CALIFORNIA MODELS ARE ALL IN GOOD AGREEMENT LIFTING IT OUT INTO
NORTHEAST COLORADO BY 12Z SATURDAY. IN RESPONSE TO THIS EJECTION THE
SUBTROPICAL RIDGING BUILDING OVER THE CENTRAL AND SOUTHERN PLAINS
GETS PULLED NORTHWARD INTO THE FORECAST AREA. AS A RESULT...THIS
HIGH PRESSURE BUILDING INTO THE FORECAST AREA RIGHT NOW AT THE
SURFACE WILL NOT HANG AROUND LONG. IN FACT...BY 00Z...15-20
SOUTHERLY 925MB WINDS ARE PROGGED AS THE HIGH SHIFTS OVER LAKE ERIE.
WE SHOULD SEE PLENTY OF SUN TODAY BEING UNDER THE INFLUENCE OF DRY
AIR NOTED ON THE 00Z MPX SOUNDING. 850MB TEMPS AT 18Z AROUND 1C IN
NORTHEAST IOWA TO -4C IN TAYLOR COUNTY SUGGESTS HIGHS FROM THE UPPER
40S TO MID 50S...COOLEST AS EXPECTED IN TAYLOR COUNTY. THINGS GET A
LITTLE MORE INTERESTING TONIGHT AS 850MB MOISTURE TRANSPORT KICKS
INTO HIGH GEAR AHEAD OF THE EJECTING UPPER LOW. 850MB WINDS
THEMSELVES ARE PROGGED TO INCREASE TO 35 TO 50 KT FROM THE SOUTHERN
PLAINS INTO THE FORECAST AREA BY 06Z...HELPING TO BRING UP THE
MOISTURE CURRENTLY SEEN ACROSS OKLAHOMA AND TEXAS. THIS RAPID
INCREASE IN MOISTURE WILL LEAD TO PRECIPITATION DEVELOPMENT...
PERHAPS AS EARLY AS 03Z AS SUGGESTED BY THE 12.00Z NAM. MORE LIKELY
IS TO HAVE WIDESPREAD SHOWERS ACROSS THE FORECAST AREA AFTER 06Z.
THUNDERSTORMS ARE ALSO EXPECTED WITH THIS ACTIVITY WITH MODELS
SHOWING UPWARDS OF 600 J/KG OF MUCAPE...MOSTLY ROOTED AT OR ABOVE
850MB PER CROSS-SECTIONS...ACCOMPANYING THE MOISTURE TRANSPORT. IN
ADDITION TO THE MOISTURE ADVECTION...850MB TEMPS ARE GOING TO SHOOT
UP...REACHING AROUND 12C BY 12Z. AS SUCH...ANTICIPATING LOWS IN THE
EVENING WITH TEMPERATURES RISING THEREAFTER.
SATURDAY AND SATURDAY NIGHT...THIS PERIOD HAS BEEN INTERESTING TO
WATCH OVER THE PAST SEVERAL DAYS WITH RESPECT TO WHAT HAPPENS WITH
THE UPPER LOW. ALL MODELS EXCLUDING THE NAM HAVE HAD ISSUES WITH THE
TRACK AND SPEED. HOWEVER...THERE IS A STRONG CONSENSUS NOW THAT THIS
UPPER LOW IS GOING TO TRACK EAST INTO SOUTHERN IOWA BY 12Z SUNDAY
AND TAKE ON A NEGATIVE TILT. MUCH OF THIS IS CAUSED BY A POTENT
SHORTWAVE HANGING BACK FROM THE UPPER LOW CROSSING THE SOUTHERN
PLAINS. THIS HAS BIG IMPLICATIONS FOR THE FORECAST AREA AS IT
DICTATES THE TRACK OF THE BEST PV ADVECTION...WHICH NOW STAYS MOSTLY
SOUTH OF THE AREA UNTIL MAYBE 12Z SUNDAY SOUTH OF I-90. STILL...
THERE IS PLENTY OF FORCING FOR PRECIPITATION. ON SATURDAY...THE
FORCING REMAINS THAT PERSISTENT STRONG 850MB MOISTURE TRANSPORT ZONE
WITH THE NOSE INTO THE FORECAST AREA. NOTE THAT THE ZONE DOES SLOWLY
SHIFT EAST IN RESPONSE TO THE APPROACHING UPPER LOW. AS SUCH...
PRECIPITATION MAY DIMINISH IN THE AFTERNOON ACROSS MINNESOTA.
PERSISTENT ADVECTION OF INSTABILITY WITHIN THE MOISTURE TRANSPORT...
WHICH SHOULD INCREASE THROUGH THE DAY AS THE AIRMASS SOUTH OF THE
AREA HEATS UP...SUGGESTS QUITE A BIT OF THUNDERSTORM ACTIVITY. BY
21Z AND CONTINUING THROUGH THE EVENING...500-1000 J/KG OF MUCAPE IS
PROGGED OVER THE FORECAST AREA...HIGHEST SOUTH OF I-90.
PRECIPITATION OVERALL LOOKS PRETTY GOOD FOR MOST OF THE AREA
SATURDAY NIGHT TOO...DUE TO A COMBINATION OF INCREASING LOW TO MID
LEVEL FRONTOGENESIS AND RIGHT ENTRANCE REGION SUPPORT FROM AN UPPER
JET DEVELOPING OVER UPPER MICHIGAN. NORTHWEST SECTIONS OF THE AREA
COULD BE ON THE EDGE OF THE PRECIPITATION... THOUGH...AS INDICATED
BY THE 12.00Z NAM AND AS SUCH SLIGHT LOWER CHANCES ARE PRESENT
THERE. GENERALLY FOLLOWED A BLEND OF GUIDANCE FOR HIGHS AND LOWS.
ONE SIDE NOTE WHICH REFLECTS THE CHANGE IN AIRMASSES...MOST
LOCATIONS WILL SEE A DEWPOINT JUMP OF 30 TO 40 DEGREES IN 24 HOURS
BETWEEN 21Z TODAY AND 21Z SATURDAY.
SEVERE WEATHER POTENTIAL FOR SATURDAY INTO SATURDAY NIGHT...ALTHOUGH
THE 500-1000 J/KG OF CAPE IN THE AFTERNOON AND EVENING IS THIN...
EXTENDING UP TO AN EQUILIBRIUM LEVEL AROUND 250MB...THE
ENVIRONMENT FOR THE MOST PART IS UNCAPPED IN THE WARM SECTOR AHEAD
OF A SURFACE LOW COMING ACROSS NORTHERN IOWA. WARM SECTOR LOOKS TO
BE SITUATED MOSTLY SOUTH OF I-90. COMBINE THIS CAPE WITH A HIGHLY
SHEARED ENVIRONMENT NOTED BY 0-6KM SHEAR OF 40-50KT AND 0-1KM
SHEAR AROUND 25 KT YIELDS CONCERN OF DISCRETE TORNADIC SUPERCELLS
IN THE WARM SECTOR. HODOGRAPHS SUGGEST STRONGLY DOMINANT RIGHT
MOVING SUPERCELLS. DAMAGING WINDS WOULD BE A CONCERN TOO GIVEN THE
SHEAR. THIN CAPE PLUS RELATIVELY HIGH FREEZING LEVELS FOR THIS
TIME OF YEAR (AROUND 11000 FT) SHOULD PRECLUDE MUCH OF A LARGE
HAIL HAZARD. OVERALL...HIGHER SEVERE THREAT SHOULD EXIST SOUTH OF
THE FORECAST AREA WHERE CAPE AND DYNAMIC FORCING IS GREATER.
SWODY2 SEVERE WEATHER PROBABILITIES DEPICT THIS WELL. IT SHOULD BE
STRESSED THAT ANY UNEXPECTED SUNSHINE ON SATURDAY COULD
DRAMATICALLY INCREASE THE SEVERE WEATHER POTENTIAL. PRESENT
FORECASTS PORTRAY A MORE LIKELY CLOUDY SCENARIO.
SUNDAY AND SUNDAY NIGHT...MODELS ARE PRETTY QUICK IN EJECTING THE
NEGATIVE TILT SHORTWAVE AND THE ASSOCIATED SURFACE SYSTEM AWAY FROM
THE AREA. BY 00Z MONDAY...BOTH FEATURES SHOULD BE NEAR LAKE HURON.
THEREFORE...AFTER SOME DEFORMATION PRECIPITATION ON THE BACK SIDE OF
THE SYSTEM AFFECTS THE AREA IN THE MORNING...ESPECIALLY ACROSS
WISCONSIN...ANTICIPATING CONDITIONS TO DRY OUT FOR THE AFTERNOON.
UPPER TROUGHING DOES LINGER OVER THE AREA THROUGH SUNDAY NIGHT...
AIDED BY A FEW PACIFIC SHORTWAVES DROPPING IN BEHIND THE NEGATIVELY
TILTED SHORTWAVE. HOWEVER...AT MOST IT LOOKS LIKE THESE WOULD BRING
CLOUDS. DESPITE BEING IN COLD ADVECTION IN THE WAKE OF SUNDAYS
SYSTEM...850MB TEMPS ONLY FALL TO 2-4C. COMBINE THIS WITH SOME
AFTERNOON SUN SHOULD BOOST HIGHS INTO THE MID 50S TO LOW
60S...WARMEST WEST OF THE MISSISSIPPI RIVER WHERE THE MOST SUN IS
EXPECTED. COULD BE A COOL NIGHT SUNDAY NIGHT WITH A SURFACE RIDGE
BUILDING IN...BUT IT WILL ALL DEPEND ON THE CLOUDS. HAVE LEANED
TOWARDS A BLEND OF GUIDANCE WITH A KNOCK DOWN IN TEMPS FOR THE
TYPICAL COOLER SPOTS. MAY HAVE TO KEEP AN EYE ON VALLEY FOG
POTENTIAL IF THE SURFACE RIDGE BUILDS IN A LITTLE FASTER AND SKIES
STAY MOSTLY CLEAR.
.LONG TERM...MONDAY THROUGH THURSDAY NIGHT
258 AM CDT FRI OCT 12 2012
12.00Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES PORTRAY YET ANOTHER
PATTERN CHANGE DURING THE LONG TERM PERIOD...FORECASTING TROUGHING
ACROSS THE NORTHERN PLAINS INTO THE WESTERN GREAT LAKES BY THURSDAY.
THIS IS SIMILAR TO WHAT WE HAVE JUST EXPERIENCED FOR THE PAST
WEEK...THOUGH THE AIR IN THE TROUGH IS NOT NEARLY AS COOL.
THE PERIOD BEGINS WITH A FAST WEST-NORTHWEST FLOW FROM THE PACIFIC
NORTHWEST INTO THE NORTHERN PLAINS. THERE ARE INDICATIONS OF A
SHORTWAVE RIDING THROUGH THIS FLOW AND AMPLIFYING A TROUGH OVER THE
NORTHERN PLAINS ON TUESDAY...CAUSING RIDGING TO DEVELOP OVER THE
FORECAST AREA. THUS...IT WOULD APPEAR MONDAY AND IN PARTICULAR
TUESDAY SHOULD BE THE WARM DAYS OF THE WEEK. 850MB TEMPS CLIMB TO
6-9C BY 00Z TUESDAY AND 8-11C BY 00Z WEDNESDAY. MAY NOT BE ABLE TO
REALIZE THE FULL WARMTH ON TUESDAY...THOUGH...AS WARM ADVECTION AND
DPVA FORCED CLOUDS AND PRECIPITATION SPREAD INTO THE AREA AHEAD OF
THE NORTHERN PLAINS TROUGH. THE NORTHERN PLAINS TROUGH IS THEN
SUGGESTED TO SHIFT EAST OVER THE AREA FOR WEDNESDAY INTO THURSDAY.
KEPT PRECIPITATION CHANCES GOING FOR WEDNESDAY INTO WEDNESDAY NIGHT
PER CONSENSUS...DUE TO A DECENT STRENGTH SHORTWAVE SUGGESTED TO DROP
INTO THE TROUGH. AS THE SHORTWAVE PUSHES OFF TO THE EAST FOR
THURSDAY...FOLLOWED A DRY FORECAST. AGAIN...TEMPERATURES WILL COOL
DOWN WEDNESDAY INTO THURSDAY AS 850MB TEMPS DROP TO 4-6C AND 2-4C
RESPECTIVELY. AFTER MONDAY THROUGH WEDNESDAY PROGGED TO MAINLY BE IN
THE 60S...THURSDAY LOOKS TO END UP THE 50S.
&&
.AVIATION...
1025 PM CDT THU OCT 11 2012
HIGH PRESSURE BUILDS IN FROM THE NORTHERN PLAINS OVERNIGHT...WITH
THE HIGH OVERHEAD BY 12Z FRI. CLEAR SKIES WITH A LIGHT WIND WILL
RESULT. IT WOULD BE A GREAT SETUP FOR RIVER VALLEY FOG...EXCEPT THE
T/TD SPREAD IS LARGE /25 DEGREES AT 02Z/ AND WILL LIKELY REMAIN THAT
WAY OVERNIGHT. IN ADDITION...DRIER AIR IS ADVECTING IN FROM THE
NORTHWEST. SO...DON/T EXPECT A FG IMPACT AT KLSE FRI MORNING.
THE HIGH WILL EXIT QUICKLY EAST ON FRI...WITH THE WINDS GRADUALLY
SHIFTING TO THE SOUTH AND INCREASING LATER IN THE DAY. CLOUDS WILL
BE ON THE INCREASE FRIDAY NIGHT AS LOW LEVEL THERMODYNAMICS AND
INCREASING SATURATION PUSH IN FROM THE SOUTH/SOUTHWEST...AHEAD OF A
LOW PRESSURE SYSTEM/COLD FRONT APPROACHING FROM THE WEST. AREAS OF
-SHRA WILL LIKELY DEVELOP FROM THE FORCING OVERNIGHT FRI...WITH SAT
LOOKING LIKE A WET DAY. ENOUGH FORCING AND INSTABILITY THAT A FEW
THUNDERSTORMS WILL BE POSSIBLE. EXPECT CIGS TO DROP INTO THE MVFR
RANGE AROUND 12Z SAT OR SHORTLY AFTER...WITH SOME VSBY RESTRICTIONS
IN THE RAIN.
&&
.HYDROLOGY...TONIGHT THROUGH SUNDAY
258 AM CDT FRI OCT 12 2012
QPF WISE FOR THE TONIGHT THROUGH SUNDAY MORNING SYSTEM...REALLY HARD
TO SAY. THE MAXIMUM AREA SHOULD BE OVER THE SOUTHEASTERN 1/3 OF THE
FORECAST AREA...WHERE THE LONGEST PERIOD OF 850MB MOISTURE TRANSPORT
NOSES IN AND THEN GETS HIT BY THE DEFORMATION ON THE BACK SIDE OF
THE SYSTEM. PRECIPITABLE WATER VALUES CLIMB TO AROUND 1.5 INCHES OR
200-250 PERCENT OF NORMAL TONIGHT AND HOVER AROUND THERE INTO SUNDAY
MORNING. POTENTIAL IS DEFINITELY THERE TO GET 1 TO 2 INCHES FOR THE
ENTIRE TIME PERIOD...AS SUGGESTED BY HPC FORECASTS AND SREF
PROBABILITIES...WITH LOCALLY HIGHER AMOUNTS DUE TO THE CONVECTIVE
NATURE. IN FACT...THE LATEST 12.00Z ECMWF HAS UPWARDS OF 3-3.5
INCHES. THE LANDSCAPE AND RIVERS REALLY COULD USE THIS RAIN GIVEN
THE SEVERE TO EXTREME DROUGHT CONDITIONS IN PLACE. THEREFORE...NO
FLOODING IS ANTICIPATED.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
258 AM CDT FRI OCT 12 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RIECK
HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
258 AM CDT FRI OCT 12 2012
.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
258 AM CDT FRI OCT 12 2012
MAIN FORECAST CONCERN IS ON SEVERE WEATHER POTENTIAL SATURDAY INTO
SATURDAY NIGHT.
CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A SPLIT FLOW PATTERN ACROSS NORTH AMERICA. IN THE NORTHERN
STREAM...WEAK RIDGING WAS NOTED OVER THE NORTHERN U.S. ROCKIES AND
THEN DOWNSTREAM TROUGHING OVER THE GREAT LAKES. IN THE SOUTHERN
STREAM...AN UPPER LOW WAS OVER SOUTHERN CALIFORNIA WITH RIDGING
BUILDING UP AHEAD OF IT ACROSS THE CENTRAL AND SOUTHERN PLAINS. OVER
THE FORECAST AREA...SATELLITE IMAGERY SHOWED SKIES HAVE CLEARED OUT
THANKS TO SUBSIDENCE AND DRYING IN THE WAKE OF THE GREAT LAKES
TROUGHING. ALSO REFLECTED OF THE SUBSIDENCE IS A 1030MB SURFACE HIGH
CENTERED NEAR MINNEAPOLIS. PRECIPITABLE WATER VALUES WERE QUITE DRY
ON THE 00Z MPX SOUNDING...0.17 INCHES OR 30 PERCENT NORMAL. SURFACE
DEWPOINTS ALSO REFLECTIVE OF THE DRYING...DOWN IN THE TEENS TO LOWER
20S. DECENT AMOUNT OF COLD AIR ACCOMPANYING THE SURFACE HIGH WITH
850MB TEMPS THAT DROPPED TO -4C AT MPX AT 00Z COMPARED TO +3C 12
HOURS EARLIER. TO THE SOUTH...A STATIONARY FRONTAL BOUNDARY WAS
POSITIONED FROM OKLAHOMA INTO THE OHIO RIVER VALLEY. SOUTH OF THIS
FRONT...PLENTIFUL MOISTURE WAS NOTED WITH SURFACE DEWPOINTS IN THE
MID 60S TO LOWER 70S ACROSS OKLAHOMA AND MUCH OF TEXAS. 00Z FORT
WORTH SOUNDING HAD A PRECIPITABLE WATER VALUE OF 1.6 INCHES OR 176
PERCENT OF NORMAL. 850MB PROFILER AND VWP DATA CURRENTLY SHOWS MUCH
OF THIS MOISTURE BEING ADVECTED INTO AND ALONG THE STATIONARY
FRONTAL BOUNDARY.
TODAY AND TONIGHT...MAJOR CHANGES LOOK TO OCCUR IN THE WEATHER
PATTERN ACROSS THE FORECAST AREA DURING THIS TIME. THE UPPER LOW IN
CALIFORNIA MODELS ARE ALL IN GOOD AGREEMENT LIFTING IT OUT INTO
NORTHEAST COLORADO BY 12Z SATURDAY. IN RESPONSE TO THIS EJECTION THE
SUBTROPICAL RIDGING BUILDING OVER THE CENTRAL AND SOUTHERN PLAINS
GETS PULLED NORTHWARD INTO THE FORECAST AREA. AS A RESULT...THIS
HIGH PRESSURE BUILDING INTO THE FORECAST AREA RIGHT NOW AT THE
SURFACE WILL NOT HANG AROUND LONG. IN FACT...BY 00Z...15-20
SOUTHERLY 925MB WINDS ARE PROGGED AS THE HIGH SHIFTS OVER LAKE ERIE.
WE SHOULD SEE PLENTY OF SUN TODAY BEING UNDER THE INFLUENCE OF DRY
AIR NOTED ON THE 00Z MPX SOUNDING. 850MB TEMPS AT 18Z AROUND 1C IN
NORTHEAST IOWA TO -4C IN TAYLOR COUNTY SUGGESTS HIGHS FROM THE UPPER
40S TO MID 50S...COOLEST AS EXPECTED IN TAYLOR COUNTY. THINGS GET A
LITTLE MORE INTERESTING TONIGHT AS 850MB MOISTURE TRANSPORT KICKS
INTO HIGH GEAR AHEAD OF THE EJECTING UPPER LOW. 850MB WINDS
THEMSELVES ARE PROGGED TO INCREASE TO 35 TO 50 KT FROM THE SOUTHERN
PLAINS INTO THE FORECAST AREA BY 06Z...HELPING TO BRING UP THE
MOISTURE CURRENTLY SEEN ACROSS OKLAHOMA AND TEXAS. THIS RAPID
INCREASE IN MOISTURE WILL LEAD TO PRECIPITATION DEVELOPMENT...
PERHAPS AS EARLY AS 03Z AS SUGGESTED BY THE 12.00Z NAM. MORE LIKELY
IS TO HAVE WIDESPREAD SHOWERS ACROSS THE FORECAST AREA AFTER 06Z.
THUNDERSTORMS ARE ALSO EXPECTED WITH THIS ACTIVITY WITH MODELS
SHOWING UPWARDS OF 600 J/KG OF MUCAPE...MOSTLY ROOTED AT OR ABOVE
850MB PER CROSS-SECTIONS...ACCOMPANYING THE MOISTURE TRANSPORT. IN
ADDITION TO THE MOISTURE ADVECTION...850MB TEMPS ARE GOING TO SHOOT
UP...REACHING AROUND 12C BY 12Z. AS SUCH...ANTICIPATING LOWS IN THE
EVENING WITH TEMPERATURES RISING THEREAFTER.
SATURDAY AND SATURDAY NIGHT...THIS PERIOD HAS BEEN INTERESTING TO
WATCH OVER THE PAST SEVERAL DAYS WITH RESPECT TO WHAT HAPPENS WITH
THE UPPER LOW. ALL MODELS EXCLUDING THE NAM HAVE HAD ISSUES WITH THE
TRACK AND SPEED. HOWEVER...THERE IS A STRONG CONSENSUS NOW THAT THIS
UPPER LOW IS GOING TO TRACK EAST INTO SOUTHERN IOWA BY 12Z SUNDAY
AND TAKE ON A NEGATIVE TILT. MUCH OF THIS IS CAUSED BY A POTENT
SHORTWAVE HANGING BACK FROM THE UPPER LOW CROSSING THE SOUTHERN
PLAINS. THIS HAS BIG IMPLICATIONS FOR THE FORECAST AREA AS IT
DICTATES THE TRACK OF THE BEST PV ADVECTION...WHICH NOW STAYS MOSTLY
SOUTH OF THE AREA UNTIL MAYBE 12Z SUNDAY SOUTH OF I-90. STILL...
THERE IS PLENTY OF FORCING FOR PRECIPITATION. ON SATURDAY...THE
FORCING REMAINS THAT PERSISTENT STRONG 850MB MOISTURE TRANSPORT ZONE
WITH THE NOSE INTO THE FORECAST AREA. NOTE THAT THE ZONE DOES SLOWLY
SHIFT EAST IN RESPONSE TO THE APPROACHING UPPER LOW. AS SUCH...
PRECIPITATION MAY DIMINISH IN THE AFTERNOON ACROSS MINNESOTA.
PERSISTENT ADVECTION OF INSTABILITY WITHIN THE MOISTURE TRANSPORT...
WHICH SHOULD INCREASE THROUGH THE DAY AS THE AIRMASS SOUTH OF THE
AREA HEATS UP...SUGGESTS QUITE A BIT OF THUNDERSTORM ACTIVITY. BY
21Z AND CONTINUING THROUGH THE EVENING...500-1000 J/KG OF MUCAPE IS
PROGGED OVER THE FORECAST AREA...HIGHEST SOUTH OF I-90.
PRECIPITATION OVERALL LOOKS PRETTY GOOD FOR MOST OF THE AREA
SATURDAY NIGHT TOO...DUE TO A COMBINATION OF INCREASING LOW TO MID
LEVEL FRONTOGENESIS AND RIGHT ENTRANCE REGION SUPPORT FROM AN UPPER
JET DEVELOPING OVER UPPER MICHIGAN. NORTHWEST SECTIONS OF THE AREA
COULD BE ON THE EDGE OF THE PRECIPITATION... THOUGH...AS INDICATED
BY THE 12.00Z NAM AND AS SUCH SLIGHT LOWER CHANCES ARE PRESENT
THERE. GENERALLY FOLLOWED A BLEND OF GUIDANCE FOR HIGHS AND LOWS.
ONE SIDE NOTE WHICH REFLECTS THE CHANGE IN AIRMASSES...MOST
LOCATIONS WILL SEE A DEWPOINT JUMP OF 30 TO 40 DEGREES IN 24 HOURS
BETWEEN 21Z TODAY AND 21Z SATURDAY.
SEVERE WEATHER POTENTIAL FOR SATURDAY INTO SATURDAY NIGHT...ALTHOUGH
THE 500-1000 J/KG OF CAPE IN THE AFTERNOON AND EVENING IS THIN...
EXTENDING UP TO AN EQUILIBRIUM LEVEL AROUND 250MB...THE
ENVIRONMENT FOR THE MOST PART IS UNCAPPED IN THE WARM SECTOR AHEAD
OF A SURFACE LOW COMING ACROSS NORTHERN IOWA. WARM SECTOR LOOKS TO
BE SITUATED MOSTLY SOUTH OF I-90. COMBINE THIS CAPE WITH A HIGHLY
SHEARED ENVIRONMENT NOTED BY 0-6KM SHEAR OF 40-50KT AND 0-1KM
SHEAR AROUND 25 KT YIELDS CONCERN OF DISCRETE TORNADIC SUPERCELLS
IN THE WARM SECTOR. HODOGRAPHS SUGGEST STRONGLY DOMINANT RIGHT
MOVING SUPERCELLS. DAMAGING WINDS WOULD BE A CONCERN TOO GIVEN THE
SHEAR. THIN CAPE PLUS RELATIVELY HIGH FREEZING LEVELS FOR THIS
TIME OF YEAR (AROUND 11000 FT) SHOULD PRECLUDE MUCH OF A LARGE
HAIL HAZARD. OVERALL...HIGHER SEVERE THREAT SHOULD EXIST SOUTH OF
THE FORECAST AREA WHERE CAPE AND DYNAMIC FORCING IS GREATER.
SWODY2 SEVERE WEATHER PROBABILITIES DEPICT THIS WELL. IT SHOULD BE
STRESSED THAT ANY UNEXPECTED SUNSHINE ON SATURDAY COULD
DRAMATICALLY INCREASE THE SEVERE WEATHER POTENTIAL. PRESENT
FORECASTS PORTRAY A MORE LIKELY CLOUDY SCENARIO.
SUNDAY AND SUNDAY NIGHT...MODELS ARE PRETTY QUICK IN EJECTING THE
NEGATIVE TILT SHORTWAVE AND THE ASSOCIATED SURFACE SYSTEM AWAY FROM
THE AREA. BY 00Z MONDAY...BOTH FEATURES SHOULD BE NEAR LAKE HURON.
THEREFORE...AFTER SOME DEFORMATION PRECIPITATION ON THE BACK SIDE OF
THE SYSTEM AFFECTS THE AREA IN THE MORNING...ESPECIALLY ACROSS
WISCONSIN...ANTICIPATING CONDITIONS TO DRY OUT FOR THE AFTERNOON.
UPPER TROUGHING DOES LINGER OVER THE AREA THROUGH SUNDAY NIGHT...
AIDED BY A FEW PACIFIC SHORTWAVES DROPPING IN BEHIND THE NEGATIVELY
TILTED SHORTWAVE. HOWEVER...AT MOST IT LOOKS LIKE THESE WOULD BRING
CLOUDS. DESPITE BEING IN COLD ADVECTION IN THE WAKE OF SUNDAYS
SYSTEM...850MB TEMPS ONLY FALL TO 2-4C. COMBINE THIS WITH SOME
AFTERNOON SUN SHOULD BOOST HIGHS INTO THE MID 50S TO LOW
60S...WARMEST WEST OF THE MISSISSIPPI RIVER WHERE THE MOST SUN IS
EXPECTED. COULD BE A COOL NIGHT SUNDAY NIGHT WITH A SURFACE RIDGE
BUILDING IN...BUT IT WILL ALL DEPEND ON THE CLOUDS. HAVE LEANED
TOWARDS A BLEND OF GUIDANCE WITH A KNOCK DOWN IN TEMPS FOR THE
TYPICAL COOLER SPOTS. MAY HAVE TO KEEP AN EYE ON VALLEY FOG
POTENTIAL IF THE SURFACE RIDGE BUILDS IN A LITTLE FASTER AND SKIES
STAY MOSTLY CLEAR.
.LONG TERM...MONDAY THROUGH THURSDAY NIGHT
258 AM CDT FRI OCT 12 2012
12.00Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES PORTRAY YET ANOTHER
PATTERN CHANGE DURING THE LONG TERM PERIOD...FORECASTING TROUGHING
ACROSS THE NORTHERN PLAINS INTO THE WESTERN GREAT LAKES BY THURSDAY.
THIS IS SIMILAR TO WHAT WE HAVE JUST EXPERIENCED FOR THE PAST
WEEK...THOUGH THE AIR IN THE TROUGH IS NOT NEARLY AS COOL.
THE PERIOD BEGINS WITH A FAST WEST-NORTHWEST FLOW FROM THE PACIFIC
NORTHWEST INTO THE NORTHERN PLAINS. THERE ARE INDICATIONS OF A
SHORTWAVE RIDING THROUGH THIS FLOW AND AMPLIFYING A TROUGH OVER THE
NORTHERN PLAINS ON TUESDAY...CAUSING RIDGING TO DEVELOP OVER THE
FORECAST AREA. THUS...IT WOULD APPEAR MONDAY AND IN PARTICULAR
TUESDAY SHOULD BE THE WARM DAYS OF THE WEEK. 850MB TEMPS CLIMB TO
6-9C BY 00Z TUESDAY AND 8-11C BY 00Z WEDNESDAY. MAY NOT BE ABLE TO
REALIZE THE FULL WARMTH ON TUESDAY...THOUGH...AS WARM ADVECTION AND
DPVA FORCED CLOUDS AND PRECIPITATION SPREAD INTO THE AREA AHEAD OF
THE NORTHERN PLAINS TROUGH. THE NORTHERN PLAINS TROUGH IS THEN
SUGGESTED TO SHIFT EAST OVER THE AREA FOR WEDNESDAY INTO THURSDAY.
KEPT PRECIPITATION CHANCES GOING FOR WEDNESDAY INTO WEDNESDAY NIGHT
PER CONSENSUS...DUE TO A DECENT STRENGTH SHORTWAVE SUGGESTED TO DROP
INTO THE TROUGH. AS THE SHORTWAVE PUSHES OFF TO THE EAST FOR
THURSDAY...FOLLOWED A DRY FORECAST. AGAIN...TEMPERATURES WILL COOL
DOWN WEDNESDAY INTO THURSDAY AS 850MB TEMPS DROP TO 4-6C AND 2-4C
RESPECTIVELY. AFTER MONDAY THROUGH WEDNESDAY PROGGED TO MAINLY BE IN
THE 60S...THURSDAY LOOKS TO END UP THE 50S.
&&
.AVIATION...
1025 PM CDT THU OCT 11 2012
HIGH PRESSURE BUILDS IN FROM THE NORTHERN PLAINS OVERNIGHT...WITH
THE HIGH OVERHEAD BY 12Z FRI. CLEAR SKIES WITH A LIGHT WIND WILL
RESULT. IT WOULD BE A GREAT SETUP FOR RIVER VALLEY FOG...EXCEPT THE
T/TD SPREAD IS LARGE /25 DEGREES AT 02Z/ AND WILL LIKELY REMAIN THAT
WAY OVERNIGHT. IN ADDITION...DRIER AIR IS ADVECTING IN FROM THE
NORTHWEST. SO...DON/T EXPECT A FG IMPACT AT KLSE FRI MORNING.
THE HIGH WILL EXIT QUICKLY EAST ON FRI...WITH THE WINDS GRADUALLY
SHIFTING TO THE SOUTH AND INCREASING LATER IN THE DAY. CLOUDS WILL
BE ON THE INCREASE FRIDAY NIGHT AS LOW LEVEL THERMODYNAMICS AND
INCREASING SATURATION PUSH IN FROM THE SOUTH/SOUTHWEST...AHEAD OF A
LOW PRESSURE SYSTEM/COLD FRONT APPROACHING FROM THE WEST. AREAS OF
-SHRA WILL LIKELY DEVELOP FROM THE FORCING OVERNIGHT FRI...WITH SAT
LOOKING LIKE A WET DAY. ENOUGH FORCING AND INSTABILITY THAT A FEW
THUNDERSTORMS WILL BE POSSIBLE. EXPECT CIGS TO DROP INTO THE MVFR
RANGE AROUND 12Z SAT OR SHORTLY AFTER...WITH SOME VSBY RESTRICTIONS
IN THE RAIN.
&&
.HYDROLOGY...TONIGHT THROUGH SUNDAY
258 AM CDT FRI OCT 12 2012
QPF WISE FOR THE TONIGHT THROUGH SUNDAY MORNING SYSTEM...REALLY HARD
TO SAY. THE MAXIMUM AREA SHOULD BE OVER THE SOUTHEASTERN 1/3 OF THE
FORECAST AREA...WHERE THE LONGEST PERIOD OF 850MB MOISTURE TRANSPORT
NOSES IN AND THEN GETS HIT BY THE DEFORMATION ON THE BACK SIDE OF
THE SYSTEM. PRECIPITABLE WATER VALUES CLIMB TO AROUND 1.5 INCHES OR
200-250 PERCENT OF NORMAL TONIGHT AND HOVER AROUND THERE INTO SUNDAY
MORNING. POTENTIAL IS DEFINITELY THERE TO GET 1 TO 2 INCHES FOR THE
ENTIRE TIME PERIOD...AS SUGGESTED BY HPC FORECASTS AND SREF
PROBABILITIES...WITH LOCALLY HIGHER AMOUNTS DUE TO THE CONVECTIVE
NATURE. IN FACT...THE LATEST 12.00Z ECMWF HAS UPWARDS OF 3-3.5
INCHES. THE LANDSCAPE AND RIVERS REALLY COULD USE THIS RAIN GIVEN
THE SEVERE TO EXTREME DROUGHT CONDITIONS IN PLACE. THEREFORE...NO
FLOODING IS ANTICIPATED.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
258 AM CDT FRI OCT 12 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RIECK
HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
905 AM PDT FRI OCT 12 2012
.DISCUSSION...AS OF 9:00 AM PDT FRIDAY...FEW LIGHT SHOWERS THIS
MORNING HAVE BASICALLY COME TO AN END. RAINFALL AMOUNTS HAVE BEEN
VERY LIGHT WITH SPOTS THAT PICKED UP ANY RAIN REPORTING LESS THAN
A TENTH OF AN INCH. PLENTY OF CLOUDS ACROSS OUR AREA ALTHOUGH
UNLIKE YESTERDAY CIG HEIGHTS ARE HIGHER AND MORE BREAKS NOTED...SO
HOPEFULLY WE WILL SEE MORE SUNSHINE BY THE AFTERNOON.
SYNOPTICALLY...THE MAIN STORY WILL BE A RIDGE OF HIGH PRESSURE
THAT WILL BUILD ACROSS CALIFORNIA STARTING THIS WEEKEND AND GOING
INTO NEXT WEEK AS A REX BLOCK. THIS WILL HELP TO BRING SEVERAL DAYS OF
GENERALLY SUNNY CONDITIONS WITH HIGHS GOING BACK TO ABOVE NORMAL
LEVELS. ONLY REAL FORECAST CONCERNS IS HOW MUCH OVERNIGHT
CLOUDS/PATCHY FOG WE WILL SEE PLUS HOW WARM IT WILL BECOME. AT
LEAST ONE DAY OF WIDESPREAD 80S AND 90S LOOK LIKELY FOR INTERIOR
SPOTS DURING THE SECOND HALF OF NEXT WEEK.
.PREVIOUS DISCUSSION...LIGHT RAIN SHOWERS CONTINUE MAINLY FROM
THE SAN FRANCISCO BAY SOUTHWARD THIS MORNING. IN THE LAST 3
HOURS...MUSTANG RIDGE IN MONTEREY COUNTY RECEIVED 0.08" WHILE THE
OAKLAND SOUTH RAWS RECEIVED 0.02" IN THAT SAME TIME FRAME. THE NAM
AND HRRR SEEM TO HAVE THE BEST HANDLE OF THE CURRENT SYNOPTIC
PATTERN...AND BOTH KEEP SCATTERED SHOWERS IN THE REGION THROUGH AT
LEAST 15Z. POPS WERE SIGNIFICANTLY INCREASED BETWEEN 12Z AND 18Z
TO ACCOUNT FOR THESE SHOWERS.
SKIES WERE CLOUDY OVERNIGHT...AS ABUNDANT MID AND LOW LEVEL
MOISTURE PREVAILED OVER THE REGION. TEMPERATURES SO FAR FELL INTO
THE 50S...SIMILAR TO THOSE OBSERVED LAST NIGHT. LOW CLOUDS WILL BE
LATE TO DISSIPATE AGAIN TODAY...AND A FEW PLACES MIGHT ONLY SEE
GLIMPSES OF BLUE SKY.
OTHERWISE...THE UPPER LEVEL LOW OVER SOUTHERN CALIFORNIA IS
FORECAST TO MOVE SLOWLY EAST NORTHEAST TOWARD SOUTHERN NV AND
NORTHERN AZ BY THIS AFTERNOON. THIS WILL RESULT IN DRY...BUT COOL
CONDITIONS OVER THE REGION. WHILE THE LOW MOVES EAST...AN UPPER
LEVEL SHORT WAVE WILL SKIRT NORTHERN CALIFORNIA...BRINGING A
SLIGHT CHANCE OF SHOWERS TO FAR NORTHERN SONOMA COUNTY.
HOWEVER...THE SHORT TERM MODELS KEEP BACKING OFF WITH REGARDS TO
PRECIPITATION WITH THIS DISTURBANCE...SO CONFIDENCE IS LOW THAT WE
WILL SEE ANY RAIN IN THIS REGION.
WEAK UPPER LEVEL RIDGING WILL BEGIN TO BUILD OVER THE REGION
DURING THE SECOND HALF OF THE WEEKEND. THIS WILL RESULT IN A
SIGNIFICANT WARMING TREND THROUGH THE AREA...WITH TEMPERATURES
NEARING NEAR NORMAL READINGS FOR THE MIDDLE OF OCTOBER.
EVEN MORE SIGNIFICANT WARMING IS FORECAST FOR THE MIDDLE OF NEXT
WEEK...WITH A 588 DM RIDGE NEARING CENTRAL CALIFORNIA. 850 MB
TEMPERATURES ARE FORECAST TO RISE OVER 11 DEGREES C BETWEEN THIS
AFTERNOON AND WEDNESDAY AFTERNOON. THIS WILL RESULT IN INLAND
TEMPERATURES REACHING THE 80S TO LOW 90S...WHILE THE COASTAL
LOCATIONS REACH THE UPPER 60S TO 70S.
THE CLIMATE PREDICTION CENTERS 6 TO 10 DAY OUTLOOK CALLS FOR
TEMPERATURES WELL ABOVE NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION...AS OF 4:45 AM FRIDAY...LIGHT SHOWERS CONTINUE THIS
MORNING...MOSTLY EAST OF THE TERMINALS THOUGH THERE HAVE BEEN
INTERMITTENT TRACES AT OAK AND SFO. SHOWERS WILL WIND DOWN LATER
THIS MORNING. CIGS MVFR NORTH OF SJC WHILE HOLDING ABOVE 3000
FROM THERE SOUTH. EXPECTING LATE CLEARING DUE TO LOW LEVEL
MOISTURE...LOW CONFIDENCE ON TIMING. LIGHT SEA BREEZE THIS AFTERNOON.
.VICINITY OF KSFO...MVFR CIGS THROUGH THE MORNING. LIGHT SHOWERS
POSSIBLE FOR THE NEXT FEW HOURS. CONDITIONS IMPROVE IN THE
AFTERNOON WITH SEA BREEZE TO AROUND 10 KT. EARLY RETURN POSSIBLE.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...CIGS 3000 TO 4000 FT THROUGH LATE
MORNING. LIGHT SEA BREEZE.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
&&
$$
PUBLIC FORECAST: BELL/RILEY
AVIATION/MARINE: AC
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
448 AM PDT FRI OCT 12 2012
.DISCUSSION...AS OF 3:35 AM PDT FRIDAY...LIGHT RAIN SHOWERS
CONTINUE MAINLY FROM THE SAN FRANCISCO BAY SOUTHWARD THIS
MORNING. IN THE LAST 3 HOURS...MUSTANG RIDGE IN MONTEREY COUNTY
RECEIVED 0.08" WHILE THE OAKLAND SOUTH RAWS RECEIVED 0.02" IN THAT
SAME TIME FRAME. THE NAM AND HRRR SEEM TO HAVE THE BEST HANDLE OF
THE CURRENT SYNOPTIC PATTERN...AND BOTH KEEP SCATTERED SHOWERS IN
THE REGION THROUGH AT LEAST 15Z. POPS WERE SIGNIFICANTLY INCREASED
BETWEEN 12Z AND 18Z TO ACCOUNT FOR THESE SHOWERS.
SKIES WERE CLOUDY OVERNIGHT...AS ABUNDANT MID AND LOW LEVEL
MOISTURE PREVAILED OVER THE REGION. TEMPERATURES SO FAR FELL INTO
THE 50S...SIMILAR TO THOSE OBSERVED LAST NIGHT. LOW CLOUDS WILL BE
LATE TO DISSIPATE AGAIN TODAY...AND A FEW PLACES MIGHT ONLY SEE
GLIMPSES OF BLUE SKY.
OTHERWISE...THE UPPER LEVEL LOW OVER SOUTHERN CALIFORNIA IS
FORECAST TO MOVE SLOWLY EAST NORTHEAST TOWARD SOUTHERN NV AND
NORTHERN AZ BY THIS AFTERNOON. THIS WILL RESULT IN DRY...BUT COOL
CONDITIONS OVER THE REGION. WHILE THE LOW MOVES EAST...AN UPPER
LEVEL SHORT WAVE WILL SKIRT NORTHERN CALIFORNIA...BRINGING A
SLIGHT CHANCE OF SHOWERS TO FAR NORTHERN SONOMA COUNTY.
HOWEVER...THE SHORT TERM MODELS KEEP BACKING OFF WITH REGARDS TO
PRECIPITATION WITH THIS DISTURBANCE...SO CONFIDENCE IS LOW THAT WE
WILL SEE ANY RAIN IN THIS REGION.
WEAK UPPER LEVEL RIDGING WILL BEGIN TO BUILD OVER THE REGION
DURING THE SECOND HALF OF THE WEEKEND. THIS WILL RESULT IN A
SIGNIFICANT WARMING TREND THROUGH THE AREA...WITH TEMPERATURES
NEARING NEAR NORMAL READINGS FOR THE MIDDLE OF OCTOBER.
EVEN MORE SIGNIFICANT WARMING IS FORECAST FOR THE MIDDLE OF NEXT
WEEK...WITH A 588 DM RIDGE NEARING CENTRAL CALIFORNIA. 850 MB
TEMPERATURES ARE FORECAST TO RISE OVER 11 DEGREES C BETWEEN THIS
AFTERNOON AND WEDNESDAY AFTERNOON. THIS WILL RESULT IN INLAND
TEMPERATURES REACHING THE 80S TO LOW 90S...WHILE THE COASTAL
LOCATIONS REACH THE UPPER 60S TO 70S.
THE CLIMATE PREDICTION CENTERS 6 TO 10 DAY OUTLOOK CALLS FOR
TEMPERATURES WELL ABOVE NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION...AS OF 4:45 AM FRIDAY...LIGHT SHOWERS CONTINUE THIS
MORNING...MOSTLY EAST OF THE TERMINALS THOUGH THERE HAVE BEEN
INTERMITTENT TRACES AT OAK AND SFO. SHOWERS WILL WIND DOWN LATER
THIS MORNING. CIGS MVFR NORTH OF SJC WHILE HOLDING ABOVE 3000
FROM THERE SOUTH. EXPECTING LATE CLEARING DUE TO LOW LEVEL
MOISTURE...LOW CONFIDENCE ON TIMING. LIGHT SEA BREEZE THIS AFTERNOON.
.VICINITY OF KSFO...MVFR CIGS THROUGH THE MORNING. LIGHT SHOWERS
POSSIBLE FOR THE NEXT FEW HOURS. CONDITIONS IMPROVE IN THE
AFTERNOON WITH SEA BREEZE TO AROUND 10 KT. EARLY RETURN POSSIBLE.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...CIGS 3000 TO 4000 FT THROUGH LATE
MORNING. LIGHT SEA BREEZE.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
&&
$$
PUBLIC FORECAST: RILEY
AVIATION/MARINE: AC
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
335 AM PDT FRI OCT 12 2012
.DISCUSSION...AS OF 3:35 AM PDT FRIDAY...LIGHT RAIN SHOWERS
CONTINUE MAINLY FROM THE SAN FRANCISCO BAY SOUTHWARD THIS
MORNING. IN THE LAST 3 HOURS...MUSTANG RIDGE IN MONTEREY COUNTY
RECEIVED 0.08" WHILE THE OAKLAND SOUTH RAWS RECEIVED 0.02" IN THAT
SAME TIME FRAME. THE NAM AND HRRR SEEM TO HAVE THE BEST HANDLE OF
THE CURRENT SYNOPTIC PATTERN...AND BOTH KEEP SCATTERED SHOWERS IN
THE REGION THROUGH AT LEAST 15Z. POPS WERE SIGNIFICANTLY INCREASED
BETWEEN 12Z AND 18Z TO ACCOUNT FOR THESE SHOWERS.
SKIES WERE CLOUDY OVERNIGHT...AS ABUNDANT MID AND LOW LEVEL
MOISTURE PREVAILED OVER THE REGION. TEMPERATURES SO FAR FELL INTO
THE 50S...SIMILAR TO THOSE OBSERVED LAST NIGHT. LOW CLOUDS WILL BE
LATE TO DISSIPATE AGAIN TODAY...AND A FEW PLACES MIGHT ONLY SEE
GLIMPSES OF BLUE SKY.
OTHERWISE...THE UPPER LEVEL LOW OVER SOUTHERN CALIFORNIA IS
FORECAST TO MOVE SLOWLY EAST NORTHEAST TOWARD SOUTHERN NV AND
NORTHERN AZ BY THIS AFTERNOON. THIS WILL RESULT IN DRY...BUT COOL
CONDITIONS OVER THE REGION. WHILE THE LOW MOVES EAST...AN UPPER
LEVEL SHORT WAVE WILL SKIRT NORTHERN CALIFORNIA...BRINGING A
SLIGHT CHANCE OF SHOWERS TO FAR NORTHERN SONOMA COUNTY.
HOWEVER...THE SHORT TERM MODELS KEEP BACKING OFF WITH REGARDS TO
PRECIPITATION WITH THIS DISTURBANCE...SO CONFIDENCE IS LOW THAT WE
WILL SEE ANY RAIN IN THIS REGION.
WEAK UPPER LEVEL RIDGING WILL BEGIN TO BUILD OVER THE REGION
DURING THE SECOND HALF OF THE WEEKEND. THIS WILL RESULT IN A
SIGNIFICANT WARMING TREND THROUGH THE AREA...WITH TEMPERATURES
NEARING NEAR NORMAL READINGS FOR THE MIDDLE OF OCTOBER.
EVEN MORE SIGNIFICANT WARMING IS FORECAST FOR THE MIDDLE OF NEXT
WEEK...WITH A 588 DM RIDGE NEARING CENTRAL CALIFORNIA. 850 MB
TEMPERATURES ARE FORECAST TO RISE OVER 11 DEGREES C BETWEEN THIS
AFTERNOON AND WEDNESDAY AFTERNOON. THIS WILL RESULT IN INLAND
TEMPERATURES REACHING THE 80S TO LOW 90S...WHILE THE COASTAL
LOCATIONS REACH THE UPPER 60S TO 70S.
THE CLIMATE PREDICTION CENTERS 6 TO 10 DAY OUTLOOK CALLS FOR
TEMPERATURES WELL ABOVE NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION...AS OF 10:30 PM THURSDAY...LARGE STRATUS FIELD
CONTINUES OVER THE AREA. MVFR CIGS ALL TERMINALS THROUGH THE
NIGHT.
.VICINITY OF KSFO...MVFR CIGS THROUGH FRIDAY MORNING. SOUTHWEST
WINDS TO 10 KT.
KSFO BRIDGE APPROACH...MVFR CIGS THROUGH FRIDAY MORNING.
MONTEREY BAY AREA TERMINALS...MVFR CIGS THROUGH EARLY FRIDAY
AFTERNOON.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
&&
$$
PUBLIC FORECAST: RILEY
AVIATION/MARINE: W PI
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AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
758 AM EDT FRI OCT 12 2012
.PREV DISCUSSION... /ISSUED 513 AM EDT FRI OCT 12 2012/
.UPDATE...
MCS TRACKING SOUTHEASTWARD ACROSS CENTRAL TN SHOULD BEGIN TO
INFLUENCE NORTHERN GEORGIA FROM THE NW AS EARLY AS 11Z. SCATTERED
THUNDERSTORM DEVELOPMENT HAS BEEN PERSISTENT OVERNIGHT AND BASED
ON RAP ANALYSIS OF MUCAPE...COMPLEX HAS BEEN RIDING ALONG AN
ELEVATED INSTABILITY AXIS. IT IS STILL EXPECTED TO BECOME LESS
ORGANIZED AND DISSIPATE MOSTLY AFTER 15Z...THOUGH HAVE INCLUDED
ISOLATED TO SCATTERED THUNDER ACROSS PARTS OF THE NORTH. BEST
CHANCE FOR ANY THUNDERSTORMS SHOULD STAY NORTH OF ATLANTA AND
EVENTUALLY BECOME MORE ISOLATED IN COVERAGE INTO MID MORNING. THE
MAIN THREATS WITH ANY THUNDERSTORM WILL BE OCCASIONAL
LIGHTNING...GUSTY WINDS...AND HEAVY RAINFALL. PREVIOUS DISCUSSION
FOLLOWS...
BAKER
&&
.PREV DISCUSSION... /ISSUED 420 AM EDT FRI OCT 12 2012/
.SHORT TERM /TODAY THROUGH SATURDAY/...
CLOUD DECK AND VERY ISOLATED SHOWER DEVELOPMENT ADVECTING INTO
NORTHERN GEORGIA EARLY THIS MORNING HAS LIMITED RADIATIONAL COOLING
SO HAVE THUS RAISED MIN TEMPS BY A FEW DEGREES. MCS CURRENTLY ACROSS
WESTERN KY AND FAR NORTHWESTERN TN IS TRACKING SOUTHEASTWARD IN
ASSOCIATION WITH SOUTHERN EXTENT OF LOW AMPLITUDE UPPER SHORTWAVE
TROUGH. THERE IS A SLIM CHANCE THAT SOME ISOLATED THUNDER COULD
REACH INTO THE FAR NORTHEASTERN PORTION OF THE AREA SHORTLY BEFORE
12Z WITH THE MCS REMNANTS...HOWEVER PROGGED MUCAPE STAYS LOW AND RAP
ANALYSIS HAS COMPLEX TRACKING INTO A MORE STABLE ENVIRONMENT SO WILL
LEAVE CHANCE POPS FOR SHOWERS THROUGH MORNING. HOWEVER...WILL
CLOSELY MONITOR PROGRESSION OF THIS SYSTEM AND UPDATE AS SEEN FIT.
SUITE OF SHORT RANGE MODEL SOLUTIONS GENERALLY AGREE WITH PRECIP
ACROSS NW GEORGIA MAINLY FROM 10-15Z...THOUGH LOOKS TO BE LIMITED IN
COVERAGE AND GREATLY TAPERS OFF INTO THE AFTERNOON AS THE BEST UPPER
LEVEL DYNAMICS STAY REMOVED FROM THE MOISTURE AND WELL NORTH OF THE
REGION. WILL THEREFORE CARRY CHANCE POPS INITIALLY NW TO SLIGHT POPS
BY AFTERNOON AND FURTHER SOUTH INTO WESTERN CENTRAL GEORGIA.
INSTABILITY CONTINUES TO BE LIMITED SO WILL STILL ONLY HAVE SHOWER
POTENTIAL THROUGH AFTERNOON.
CLASSIC CAD EVENT SETS UP FOR SATURDAY WITH 1033-MB PARENT SFC HIGH
PROGGED TO BE CENTERED OVER NEW ENGLAND/MID ATLANTIC REGION BY 12Z.
RESULTANT WEDGE SHOULD LIMIT MAX TEMPS FROM NEAR 70 DEGREES IN THE
NORTHEAST PORTION TO NEAR 80 IN THE SOUTH. GENERALLY A BLEND OF
BIASED CORRECTED MET AND MAV GUIDANCE LOOKED REASONABLE FOR PROGGED
TEMPS THROUGH PERIOD.
BAKER
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
EXTENDED PERIOD BEGINS WITH A SHORTWAVE MOVING THROUGH THE
MISSOURI VALLEY NORTHEAST INTO THE OHIO VALLEY. TRAILING RESIDUAL
ENERGY WILL PUSH INTO THE AREA SUNDAY NIGHT INTO MONDAY WITH A
BROKEN LINE OF SHOWERS AND EMBEDDED THUNDERSTORMS THE RESULT.
INSTABILITY SUFFICIENT FOR STORM DEVELOPMENT BUT MOST SIGNIFICANT
SHEAR LIFTS NORTH OF THE AREA SO EXPECTING NOTHING SIGNIFICANT
LOCALLY AT THIS POINT. HIGH PRESSURE WILL THEN BUILD IN BEHIND THE
FRONT BUT LARGELY ZONAL FLOW WILL KEEP TEMPS ELEVATED THROUGH MID
WEEK.
EXTENDED GUIDANCE COMING INTO BETTER AGREEMENT WRT NEXT MAJOR
SYSTEM SLATED FOR THU. MAIN LOW TO LIFT WELL NORTH OVER THE GREAT
LAKES REGION BUT UPPER TROUGH EXTENDS WELL INTO THE GULF AND WITH
A SPLIT FLOW PATTERN AT THE JET STREAM LEVEL...MODELS HAVE NO
TROUBLE GENERATING PRECIP AREAWIDE. WILL HOLD AT HIGH END CHANCE
FOR NOW THIS FAR OUT AND THE FACT THAT THIS IS THE FIRST RUN
MODELS HAVE SHOWN THIS TYPE OF CONSENSUS.
DEESE
&&
.AVIATION...
12Z UPDATE...
INITIAL MVFR CIGS NEAR 3 KFT IMPROVING TO VFR LEVELS AROUND 4 KFT AFTER
16Z FOR KATL AND OTHER NORTHERN SITES WITH SLIGHTLY HIGHER LEVELS
LIKELY NEAR KMCN AND KCSG. MCS REMNANTS LOOK TO CONTINUE WEAKENING SO
THERE COULD BE SOME VCSH NEAR KATL AND OTHER NORTHERN SITES FROM
14-16Z...THOUGH THUNDER THREAT LOOKS TO BE TOO LOW TO INCLUDE.
WINDS SHOULD STAY NW AT 10KTS OR LESS WITH SLIGHTLY HIGHER AT KATL
AFTER AROUND 18Z. WINDS SHOULD SHIFT TO NE NEAR 05Z SATURDAY AND
SOME CIG LOWERING IS POSSIBLE AS CAD WEDGE BUILDS IN...THOUGH WILL
INCLUDE SCT025 FOR NOW AND AMEND AS MORE INFORMATION BECOMES AVAILABLE.
//ATL CONFIDENCE...12Z UPDATE...
MEDIUM CONFIDENCE ON CIGS OVERNIGHT.
HIGH CONFIDENCE ALL ELSE.
BAKER
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 78 55 72 46 / 20 10 5 0
ATLANTA 79 57 74 52 / 20 10 5 10
BLAIRSVILLE 69 49 68 45 / 30 5 5 5
CARTERSVILLE 77 53 75 48 / 30 10 5 10
COLUMBUS 85 63 80 56 / 20 20 5 10
GAINESVILLE 74 56 70 49 / 30 5 5 10
MACON 83 59 80 49 / 10 10 5 0
ROME 76 54 77 48 / 30 10 5 10
PEACHTREE CITY 79 58 75 48 / 20 20 5 10
VIDALIA 84 63 79 55 / 5 5 5 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BAKER
LONG TERM....DEESE
AVIATION...BAKER
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
723 AM EDT FRI OCT 12 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 606 AM EDT FRI OCT 12 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW CONFLUENT NW FLOW
ALF OVER THE UPR GRT LKS BTWN TROFFING OVER ERN CANADA AND A RDG
OVER WRN CANADA. AT THE SFC...HI PRES IS CENTERED OVER WRN MN...WITH
CHILLY /H85 TEMPS -7C TO -8C/ NW FLOW DOMINATING THE CWA. DESPITE
RATHER MOIST LOOK TO 00Z INL/YPL RAOBS AND SUFFICIENT INSTABILITY
FOR LK EFFECT PCPN /LK SUP WATER TEMPS 8C OVER THE W TO 10C OVER THE
E/...THE BULK OF THE LK EFFECT SHRASN AND FOR THAT MATTER THE LO
CLDS ARE CONFINED TO AN AREA OVER THE ECNTRL PART OF THE LK...WHERE
THE SFC OBS INDICATE SOME LLVL CNVGC BTWN THE LARGER SCALE NW FLOW
AND A MORE NNE LAND BREEZE FLOW OFF SE ONTARIO ENHANCE BY DIURNAL
COOLING THERE. SEEMS LIKE INTENSE SUBIDENCE/DRYING ALF IN THE WAKE
OF SHRTWV THAT PASSED YDAY AS WELL AS LARGER SCALE ACYC FLOW
ASSOCIATED WITH MN HI PRES IS SUPPRESSING THE PCPN/CLD COVER.
HOWEVER...MQT RADAR DOES INDICATE SOME REFLECTIVIES OVER 30DBZ
WITHIN THE MORE INTENSE SHRASN STREAMING INTO ALGER/NRN SCHOOLCRAFT
COUNTIES.
MAIN FCST CONCERNS IN THE SHORT TERM ARE LK EFFECT SHRASN TRENDS
THIS MRNG. FOCUS FOR LATER TNGT SHIFTS TO CHC OF PCPN AS DVLPG SW
WIND ON THE WRN FLANK OF RETREATING HI PRES IS PROGGED TO ADVECT
MUCH MOISTER AIR NEWD INTO THE UPR LKS.
TODAY...WITH RISING H5 HGTS THRU THE DAY...SFC HI PRES CENTER IS
PROGGED TO MOVE STEADILY ESEWD TO OVER LAKE ERIE BY 00Z SAT. AS THE
LLVL FLOW BACKS TO THE SW THIS AFTN AND ADVECTS MUCH DRIER AIR SHOWN
ON THE 00Z MPX RAOB INTO THE UPR LKS...EXPECT LK EFFECT SHRASN OVER
THE E TO BECOME INCRSGLY CONFINED TO NEAR THE SHORE E OF GRAND
MARAIS AND THEN END COMPLETELY IN THE AFTN IN THE PRESENCE OF
DAYTIME HEATING. TO THE W...ANY LINGERING LK CLDS SHOULD GIVE WAY TO
MOSUNNY CONDITIONS/SCT CU WITH THE ARRIVAL OF THE DRIER AIR FM THE
SW. DIURNAL SC MIGHT BE MORE RESILIENT OVER THE E WITH LINGERING H85
THERMAL TROF/H85 TEMPS ARND -5C THRU 00Z. PER MIXING TO H85-8 ON NAM
FCST SDNGS AND HI TEMPS OBSVD UPSTREAM YDAY...EXPECT MAX TEMPS IN
THE 40S.
TNGT...AS THE SFC HI SHIFTS TOWARD THE MID ATLANTIC STATES AND A
SHRTWV/SFC LO SHIFT OUT OF THE CENTRAL ROCKIES INTO THE PLAINS...A
STRENGTHENING SW FLOW IS FCST TO DVLP OVER THE UPR LKS. MOST RECENT
MODEL RUNS HAVE BEEN CONSISTENT IN GENERATING SOME LGT PCPN OVER
MUCH OF THE W HALF OF THE CWA IN THIS WAD REGIME FEATURING
IMPRESSIVE ISENTROPIC ASCENT ON THE 295-305K SFCS THAT ADVECTS PWAT
UP TO 1 INCH /175-200 PCT OF NORMAL/ NEAR THE WI BORDER BY 12Z SAT.
ALTHOUGH THE BETTER HGT FALLS/DPVA/UPR DVGC LAG TO THE W CLOSER TO
THE SHRTWV IN THE PLAINS SO THAT THE LYR ABV H65-6 REMAINS
RELATIVELY DRY /INCLUDING THE DGZ/...THIS IMPRESSIVE WAD/MOISTENING
JUSTIFIES AT LEAST LO CHC POPS OVER THE W HALF NEAR THE WI BORDER.
INCRSG CLDS/WINDS WL LIMIT THE DIURNAL FALL OF TEMP...AND FCST
THERMAL PROFILES INDICATE ANY PCPN SHOULD BE IN THE FORM OF RA EVEN
THOUGH TEMPS AT SOME OF THE INTERIOR COLD SPOTS MIGHT FALL AOB 32
EARLY IN THE EVNG BEFORE THE THICKER CLDS ARRIVE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 606 AM EDT FRI OCT 12 2012
AS THE MID LEVEL TROUGH AND ASSOC SFC LOW MOVE OUT OVER THE CENTRAL
PLAINS ON SAT...STRONG WAA/ISENTROPIC ASCENT WILL CONTINUE OVER THE
FCST AREA...ESPECIALLY THRU MID DAY SAT. LIKELY TO CATEGORICAL POPS
ARE STILL WARRANTED ACROSS MUCH OF THE FCST AREA. SINCE MODELS ARE
INDICATING THE STRONGEST PUSH OF 295-300K ASCENT OVER SCNTRL AND ERN
UPPER MI...WILL MAINTAIN HIGHEST CATEGORICAL POPS 80-90 PCT OVER
THESE AREAS WHILE TAPERING POPS TO CHC 40-50 OVER NW AWAY FM BEST
WAA/ISNETROPIC ASCENT.
SAT NIGHT/SUN...MODELS SHOW SHORTWAVE TROUGH OVER THE PLAINS LIFTING
NE...CROSSING LWR MI SUN WITH ASSOCIATED SFC LOW TRACKING THRU NRN
LWR MI. THE GFS IS A BIT FASTER THAN THE ECMWF/CANADIAN SOLN BUT ALL
THESE MODELS HAVE THE SFC LOW TRACKING ACROSS NRN LOWER MI FM EITHER
EARLY SUN AFTERNOON (GFS) TO LATE SUN AFTERNOON (ECMWF/CANADIAN).
BASED ON THIS SFC LOW TRACK WHICH IS JUST SOUTH OF THE PROGGED TRACK
OF THE 850 MB...WOULD EXPECT DEFORMATION ZONE/HEAVIEST RAINFALL TO
CROSS THE S CENTRAL AND ERN PORTIONS OF THE FCST AREA. THESE AREAS
OF THE CWA ALSO LINE UP WITH MODEL INDICATED DEEP LAYER Q-VECT CONV
AND ARE CO-LOCATED WITH COUPLED UPPER JET STRUCTURE AND ALONG AND
SOUTH OF ASSOC 850 MB FGEN FORCING. AGAIN HAVE TAPERING POPS FROM
90-100 PCT SCNTRL AND EAST TO CHC POPS (30-40 PCT) FAR WEST FOR SAT
NIGHT AND SUNDAY. LOOKING AT MODEL AVG QPF...WOULD EXPECT TO SEE
RAINFALL AMOUNTS WELL OVER AN INCH OVER SCNTRL AND ERN PORTIONS OF
THE CWA WITH SOME LOCATIONS PERHAPS APPROACHING TWO INCHES. AS
SYSTEM CONTINUES TO LIFT NE...DRYING TREND WILL GET UNDERWAY FROM W
TO E LATE IN THE DAY SUN. THE DRYING TREND WILL CONTINUE SUNDAY
NIGHT AS HIGH PRES BUILDS IN FM THE WEST.
WITH SFC HIGH PRES RIDGE PASSING OVER THE AREA MON...EXPECT A DRY
DAY AFTER PERHAPS TO FEW LINGERING SHOWERS EARLY MORNING EAST.
STILL PLENTY OF MODEL UNCERTAINTY FOR NEXT WEEK. MORE ZONAL FLOW FOR
EARLY NEXT WEEK WITH WAA AND POTENTIAL FOR WEAK SHORTWAVES MOVING
THROUGH REGION COULD SUPPORT SOME LIGHT RAIN CHCS LATE MON NIGHT
INTO TUESDAY. MODELS THEN DIFFER ON HOW MUCH MID LVL TROF WILL
AMPLIFY OVER THE PLAINS FOR MID TO LATE NEXT WEEK. UNTIL MODELS COME
INTO BETTER AGREEMENT ON TROF EVOLUTION WILL MAINTAIN GOING CHC POPS
FOR MID TO LATE NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 722 AM EDT FRI OCT 12 2012
AS A DRY HI PRES RDG MOVES ACRS THE UPR LKS...EXPECT VFR CONDITIONS
TO PREDOMINATE INTO TNGT. THE ONE EXCEPTION WILL BE AT CMX THIS
MRNG...WHERE UPSLOPE WNW FLOW WL RESULT IN SOME MVFR CIGS AT TIMES.
A STRENGTHENING SSW FLOW TNGT BTWN THE DEPARTING HI AND LO PRES
TAKING SHAPE IN THE PLAINS WL RESULT IN SOME MARGINAL LLWS AS WELL AS
INCRSG CLDS. ENUF MSTR MAY ARRIVE LATE IN THE FCST PERIOD TO CAUSE
MVFR CIGS CLOSER TO THE WI BORDER AT IWD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 606 AM EDT FRI OCT 12 2012
EXPECT NW WINDS UP TO 25 KTS OVER THE HALF OF THE LAKE THIS MORNING
TO BACK STEADILY TO THE SW TODAY AS THE HI PRES CENTER OVER MN MOVES
STEADILY TO LAKE ERIE BY THIS EVENING. A STEADY SSW WIND UP TO 25
KTS WILL PREVAIL TONIGHT BETWEEN THE DEPARTING HI AND DEVELOPING LO
PRES IN THE PLAINS. AS THE LO PRES CENTER MOVES TO THE E JUST S OF
UPPER MI EARLY SUN...LOOK FOR THE WINDS TO BACK TO THE N AND
INCREASE UP TO 25 TO 30 KTS...ESPECIALLY OVER THE E HALF. MAY SEE A
FEW GALE FORCE GUSTS OVER PORTIONS OF EASTERN LAKE SUPERIOR SUN. THE
APPROACH OF HI PRES ON MON WILL CAUSE A STEADY DECREASE IN WIND
SPEED LATER SUN INTO MON. SOUTH WINDS WILL INCREASE TO 25 KTS OVER
MAINLY THE ERN HALF OF THE LAKE ON TUESDAY AHEAD OF A LOW PRESSURE
SYSTEM DEVELOPING OVER THE NRN PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...VOSS
AVIATION...KC
MARINE...KC/VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
608 AM EDT FRI OCT 12 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 606 AM EDT FRI OCT 12 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW CONFLUENT NW FLOW
ALF OVER THE UPR GRT LKS BTWN TROFFING OVER ERN CANADA AND A RDG
OVER WRN CANADA. AT THE SFC...HI PRES IS CENTERED OVER WRN MN...WITH
CHILLY /H85 TEMPS -7C TO -8C/ NW FLOW DOMINATING THE CWA. DESPITE
RATHER MOIST LOOK TO 00Z INL/YPL RAOBS AND SUFFICIENT INSTABILITY
FOR LK EFFECT PCPN /LK SUP WATER TEMPS 8C OVER THE W TO 10C OVER THE
E/...THE BULK OF THE LK EFFECT SHRASN AND FOR THAT MATTER THE LO
CLDS ARE CONFINED TO AN AREA OVER THE ECNTRL PART OF THE LK...WHERE
THE SFC OBS INDICATE SOME LLVL CNVGC BTWN THE LARGER SCALE NW FLOW
AND A MORE NNE LAND BREEZE FLOW OFF SE ONTARIO ENHANCE BY DIURNAL
COOLING THERE. SEEMS LIKE INTENSE SUBIDENCE/DRYING ALF IN THE WAKE
OF SHRTWV THAT PASSED YDAY AS WELL AS LARGER SCALE ACYC FLOW
ASSOCIATED WITH MN HI PRES IS SUPPRESSING THE PCPN/CLD COVER.
HOWEVER...MQT RADAR DOES INDICATE SOME REFLECTIVIES OVER 30DBZ
WITHIN THE MORE INTENSE SHRASN STREAMING INTO ALGER/NRN SCHOOLCRAFT
COUNTIES.
MAIN FCST CONCERNS IN THE SHORT TERM ARE LK EFFECT SHRASN TRENDS
THIS MRNG. FOCUS FOR LATER TNGT SHIFTS TO CHC OF PCPN AS DVLPG SW
WIND ON THE WRN FLANK OF RETREATING HI PRES IS PROGGED TO ADVECT
MUCH MOISTER AIR NEWD INTO THE UPR LKS.
TODAY...WITH RISING H5 HGTS THRU THE DAY...SFC HI PRES CENTER IS
PROGGED TO MOVE STEADILY ESEWD TO OVER LAKE ERIE BY 00Z SAT. AS THE
LLVL FLOW BACKS TO THE SW THIS AFTN AND ADVECTS MUCH DRIER AIR SHOWN
ON THE 00Z MPX RAOB INTO THE UPR LKS...EXPECT LK EFFECT SHRASN OVER
THE E TO BECOME INCRSGLY CONFINED TO NEAR THE SHORE E OF GRAND
MARAIS AND THEN END COMPLETELY IN THE AFTN IN THE PRESENCE OF
DAYTIME HEATING. TO THE W...ANY LINGERING LK CLDS SHOULD GIVE WAY TO
MOSUNNY CONDITIONS/SCT CU WITH THE ARRIVAL OF THE DRIER AIR FM THE
SW. DIURNAL SC MIGHT BE MORE RESILIENT OVER THE E WITH LINGERING H85
THERMAL TROF/H85 TEMPS ARND -5C THRU 00Z. PER MIXING TO H85-8 ON NAM
FCST SDNGS AND HI TEMPS OBSVD UPSTREAM YDAY...EXPECT MAX TEMPS IN
THE 40S.
TNGT...AS THE SFC HI SHIFTS TOWARD THE MID ATLANTIC STATES AND A
SHRTWV/SFC LO SHIFT OUT OF THE CENTRAL ROCKIES INTO THE PLAINS...A
STRENGTHENING SW FLOW IS FCST TO DVLP OVER THE UPR LKS. MOST RECENT
MODEL RUNS HAVE BEEN CONSISTENT IN GENERATING SOME LGT PCPN OVER
MUCH OF THE W HALF OF THE CWA IN THIS WAD REGIME FEATURING
IMPRESSIVE ISENTROPIC ASCENT ON THE 295-305K SFCS THAT ADVECTS PWAT
UP TO 1 INCH /175-200 PCT OF NORMAL/ NEAR THE WI BORDER BY 12Z SAT.
ALTHOUGH THE BETTER HGT FALLS/DPVA/UPR DVGC LAG TO THE W CLOSER TO
THE SHRTWV IN THE PLAINS SO THAT THE LYR ABV H65-6 REMAINS
RELATIVELY DRY /INCLUDING THE DGZ/...THIS IMPRESSIVE WAD/MOISTENING
JUSTIFIES AT LEAST LO CHC POPS OVER THE W HALF NEAR THE WI BORDER.
INCRSG CLDS/WINDS WL LIMIT THE DIURNAL FALL OF TEMP...AND FCST
THERMAL PROFILES INDICATE ANY PCPN SHOULD BE IN THE FORM OF RA EVEN
THOUGH TEMPS AT SOME OF THE INTERIOR COLD SPOTS MIGHT FALL AOB 32
EARLY IN THE EVNG BEFORE THE THICKER CLDS ARRIVE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 606 AM EDT FRI OCT 12 2012
AS THE MID LEVEL TROUGH AND ASSOC SFC LOW MOVE OUT OVER THE CENTRAL
PLAINS ON SAT...STRONG WAA/ISENTROPIC ASCENT WILL CONTINUE OVER THE
FCST AREA...ESPECIALLY THRU MID DAY SAT. LIKELY TO CATEGORICAL POPS
ARE STILL WARRANTED ACROSS MUCH OF THE FCST AREA. SINCE MODELS ARE
INDICATING THE STRONGEST PUSH OF 295-300K ASCENT OVER SCNTRL AND ERN
UPPER MI...WILL MAINTAIN HIGHEST CATEGORICAL POPS 80-90 PCT OVER
THESE AREAS WHILE TAPERING POPS TO CHC 40-50 OVER NW AWAY FM BEST
WAA/ISNETROPIC ASCENT.
SAT NIGHT/SUN...MODELS SHOW SHORTWAVE TROUGH OVER THE PLAINS LIFTING
NE...CROSSING LWR MI SUN WITH ASSOCIATED SFC LOW TRACKING THRU NRN
LWR MI. THE GFS IS A BIT FASTER THAN THE ECMWF/CANADIAN SOLN BUT ALL
THESE MODELS HAVE THE SFC LOW TRACKING ACROSS NRN LOWER MI FM EITHER
EARLY SUN AFTERNOON (GFS) TO LATE SUN AFTERNOON (ECMWF/CANADIAN).
BASED ON THIS SFC LOW TRACK WHICH IS JUST SOUTH OF THE PROGGED TRACK
OF THE 850 MB...WOULD EXPECT DEFORMATION ZONE/HEAVIEST RAINFALL TO
CROSS THE S CENTRAL AND ERN PORTIONS OF THE FCST AREA. THESE AREAS
OF THE CWA ALSO LINE UP WITH MODEL INDICATED DEEP LAYER Q-VECT CONV
AND ARE CO-LOCATED WITH COUPLED UPPER JET STRUCTURE AND ALONG AND
SOUTH OF ASSOC 850 MB FGEN FORCING. AGAIN HAVE TAPERING POPS FROM
90-100 PCT SCNTRL AND EAST TO CHC POPS (30-40 PCT) FAR WEST FOR SAT
NIGHT AND SUNDAY. LOOKING AT MODEL AVG QPF...WOULD EXPECT TO SEE
RAINFALL AMOUNTS WELL OVER AN INCH OVER SCNTRL AND ERN PORTIONS OF
THE CWA WITH SOME LOCATIONS PERHAPS APPROACHING TWO INCHES. AS
SYSTEM CONTINUES TO LIFT NE...DRYING TREND WILL GET UNDERWAY FROM W
TO E LATE IN THE DAY SUN. THE DRYING TREND WILL CONTINUE SUNDAY
NIGHT AS HIGH PRES BUILDS IN FM THE WEST.
WITH SFC HIGH PRES RIDGE PASSING OVER THE AREA MON...EXPECT A DRY
DAY AFTER PERHAPS TO FEW LINGERING SHOWERS EARLY MORNING EAST.
STILL PLENTY OF MODEL UNCERTAINTY FOR NEXT WEEK. MORE ZONAL FLOW FOR
EARLY NEXT WEEK WITH WAA AND POTENTIAL FOR WEAK SHORTWAVES MOVING
THROUGH REGION COULD SUPPORT SOME LIGHT RAIN CHCS LATE MON NIGHT
INTO TUESDAY. MODELS THEN DIFFER ON HOW MUCH MID LVL TROF WILL
AMPLIFY OVER THE PLAINS FOR MID TO LATE NEXT WEEK. UNTIL MODELS COME
INTO BETTER AGREEMENT ON TROF EVOLUTION WILL MAINTAIN GOING CHC POPS
FOR MID TO LATE NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 127 AM EDT FRI OCT 12 2012
PREDOMINATE NW WINDS OFF LAKE SUPERIOR WILL KEEP MOISTURE ENOUGH TO
PRODUCE SCT TO BKN CLOUD COVER WITH VFR CONDITIONS OVERNIGHT. BY
FRIDAY MORNING...A HIGH PRESSURE RIDGE WILL CAUSE A WIND SHIFT TO
THE WEST /AND EVENTUALLY TO THE SOUTHWEST BY 18Z/. IN DOING
SO...KCMX WILL SEE LINGERING MOISTURE AND RESULTING CLOUD COVER OFF
THE LAKE THROUGH THE AFTERNOON. HOWEVER THIS SHOULD CUT OFF MOISTURE
SOURCE FOR KIWD AND KSAW...SO EXPECT THESE SITES TO CLEAR OUT. PUT
IN SOME LLWS FOR ALL 3 SITES FRI EVENING AHEAD OF THE NEXT SYSTEM TO
AFFECT THE AREA.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 606 AM EDT FRI OCT 12 2012
EXPECT NW WINDS UP TO 25 KTS OVER THE HALF OF THE LAKE THIS MORNING
TO BACK STEADILY TO THE SW TODAY AS THE HI PRES CENTER OVER MN MOVES
STEADILY TO LAKE ERIE BY THIS EVENING. A STEADY SSW WIND UP TO 25
KTS WILL PREVAIL TONIGHT BETWEEN THE DEPARTING HI AND DEVELOPING LO
PRES IN THE PLAINS. AS THE LO PRES CENTER MOVES TO THE E JUST S OF
UPPER MI EARLY SUN...LOOK FOR THE WINDS TO BACK TO THE N AND
INCREASE UP TO 25 TO 30 KTS...ESPECIALLY OVER THE E HALF. MAY SEE A
FEW GALE FORCE GUSTS OVER PORTIONS OF EASTERN LAKE SUPERIOR SUN. THE
APPROACH OF HI PRES ON MON WILL CAUSE A STEADY DECREASE IN WIND
SPEED LATER SUN INTO MON. SOUTH WINDS WILL INCREASE TO 25 KTS OVER
MAINLY THE ERN HALF OF THE LAKE ON TUESDAY AHEAD OF A LOW PRESSURE
SYSTEM DEVELOPING OVER THE NRN PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...VOSS
AVIATION...07
MARINE...KC/VOSS
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
934 AM MDT FRI OCT 12 2012
.SHORT TERM...VALID FOR TDY AND SAT...
UPDATE TO ZFP AND WRKAFP. AREAS OF DENSE FOG WERE HOLDING IN
PLACE ALONG PORTIONS OF THE YELLOWSTONE AND MUSSELSHELL RIVER
VALLEYS THIS MORNING PER SPOTTER REPORTS...SATELLITE IMAGERY AND
THE KBIL SURFACE OBSERVATION. LATEST HRRR SHOWED THE FOG BURNING
OFF BETWEEN 16 AND 17Z. ADJUSTED GRIDS TO REFLECT INCREASED SKY
COVER AND FOG OVER THESE AREAS THIS MORNING. ALSO LOWERED
TEMPERATURES 5 TO 10 DEGREES IN THE FOG AREAS AS A FEW HOURS OF
GOOD DAYTIME HEATING WERE LOST THIS MORNING. WRF BUFKIT SOUNDINGS
CONTINUED TO ADVERTISE MIXING BETWEEN 600 MB W TO 800 MB E THIS
AFTERNOON...RESULTING IN TEMPERATURES IN THE 70S OVER MANY AREAS.
UPPER LOW OVER THE NV/CA BORDER IN WATER VAPOR IMAGERY THIS
MORNING WILL MOVE E THIS AFTERNOON. NEW WRF HAD ENERGY AND
MOISTURE FROM THE LOW REMAINING SOUTH OF THE FORECAST AREA.
REMAINDER OF FORECAST LOOKED FINE FOR NOW. ARTHUR
.LONG TERM...VALID FOR SUN...MON...TUE...WED...THU...
ONLY A FEW CHANGES AGAIN THIS MORNING TO THE EXTENDED
FORECAST...MAINLY CONTINUING TO TREND TEMPS SLIGHTLY
HIGHER...TOWARDS MEX GUIDANCE AND MIX DOWN NUMBERS. OVERALL...THE
EXTENDED FORECAST IS LOOKING WINDY AND MILD...WITH GOOD PRECIP
POTENTIAL IN THE HIGH TERRAIN...AND POTENTIAL FOR ISOLATED TO
SCATTERED SHOWERS ACROSS THE PLAINS AT TIMES.
ZONAL FLOW WITH A BIT OF HIGH PRESSURE RIDGING TO START THE
EXTENDED PERIOD...WILL BRING DOWNSLOPE FLOW ACROSS THE REGION
PUSHING HIGHS 5 TO 10 DEGREES ABOVE NORMAL FOR SUNDAY AND MONDAY.
THERE WILL BE A SLIGHT CHANCE FOR PRECIP IN THE HIGH TERRAIN OF
CENTRAL MONTANA AS FLOW IS FORCED UPWARD. MORE IMPORTANTLY...GUSTY
WINDS WILL BE A DAILY ISSUE AS 700MB WINDS WILL MIX DOWN TO THE
SFC...ESPECIALLY MONDAY AND TUESDAY...WITH SOME POTENTIAL 50KNOT
GUSTS APPROACHING GROUND LEVEL. A TROF AND ASSOCIATED COLD FRONT
WILL PUSH THROUGH SOUTH CENTRAL AND SOUTHEASTERN MONTANA
TUESDAY...BRINGING MUCH IMPROVED PRECIP POTENTIAL TO THE THE AREA
MOUNTAINS...AND A SLIGHT CHANCE ACROSS THE PLAINS. THIS SYSTEM
WILL ALSO BRING A STRONG PUSH OF WEST TO NORTHWEST WINDS BEHIND
THE FRONT. THIS SYSTEM WILL BRING A RETURN OF NORTHWEST FLOW
ALOFT...AND COOLER TEMPS ACROSS THE REGION. ANOTHER PACIFIC TROF
BEGINS PUSH INTO THE REGION LATE FRIDAY NIGHT...SWITCHING THE FLOW
MORE SOUTHWESTERLY...AND POINTING TOWARD ANOTHER CHANCE FOR PRECIP
ACROSS THE REGION. AAG
&&
.AVIATION...
AN AREA OF FOG THROUGH THE YELLOWSTONE RIVER VALLEY...PRODUCING
LIFR FLYING WEATHER...WILL LIFT BY 18Z. THIS WILL IMPACT KBIL.
SOUTHWEST WINDS WILL GUST TO 25KTS FROM KLVM TO KBIL BY THIS
AFTERNOON. TWH
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SAT SUN MON TUE WED THU
-------------------------------------------------------
BIL 065 046/066 048/070 050/073 052/064 042/058 040/061
0/B 00/B 11/N 11/N 22/W 22/W 11/B
LVM 075 039/066 039/069 048/068 043/059 033/053 032/054
0/U 01/B 21/N 12/W 33/W 22/W 21/B
HDN 069 043/070 045/072 044/075 046/066 040/059 038/061
0/U 00/B 11/B 11/B 22/W 22/W 11/B
MLS 070 044/070 043/070 047/075 047/066 041/060 040/062
0/U 00/U 11/B 11/B 22/W 22/W 11/B
4BQ 076 045/071 043/069 046/074 048/064 041/059 039/061
0/U 00/U 10/B 00/B 22/W 22/W 11/B
BHK 068 043/067 039/066 044/072 046/063 041/057 038/060
0/U 00/N 10/B 00/B 22/W 22/W 11/N
SHR 077 045/068 040/068 042/073 044/064 037/057 035/060
0/U 00/B 10/B 00/B 23/W 32/W 21/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
640 AM CDT FRI OCT 12 2012
.DISCUSSION.../ISSUED AT 415 AM CDT/
HIGH PRESSURE WILL SHIFT OFF TO THE EAST DURING THE DAY TODAY
ALLOWING FOR A DECENT SOUTHERLY RETURN FLOW TO DEVELOP. 900 MB WINDS
FORECAST TO INCREASE INTO THE 25 TO 30 KTS RANGE BY THIS AFTERNOON
WEST OF INTERSTATE 29...WITH SLIGHTLY LOWER VALUES TO THE EAST. THIS
SHOULD SUPPORT WIND GUSTS IN THE 25 TO 35 MPH RANGE BY THIS
AFTERNOON...WITH THE HIGHEST GUSTS WEST OF THE JAMES RIVER. MODELS
IN PRETTY GOOD AGREEMENT ON HIGH TEMPERATURES...GENERALLY EXPECTING
MID 50S SOUTHWEST MINNESOTA TO AROUND 60 ALONG THE MISSOURI RIVER.
DESPITE THE COOLER TEMPERATURES...AFTERNOON RELATIVE HUMIDITY VALUES
LIKELY TO BE IN THE 20 TO 25 PERCENT RANGE WITH DEWPOINTS ONLY IN
THE TEENS. THIS WILL CREATE ELEVATED FIRE DANGER ACROSS THE ENTIRE
CWA. ISSUES A RED FLAG WARNING FOR AREAS ALONG AND NORTH OF
INTERSTATE 90...AS THESE ZONES ARE MOST LIKELY TO EXCEED CRITERIA.
OTHER ZONES WILL BE CLOSE...BUT THINK WINDS WILL FALL JUST SHORT
ACROSS NORTHWEST IOWA AND FAR SOUTHEAST SOUTH DAKOTA.
OUR FIRST SIGNIFICANT STORM SYSTEM IN AWHILE WILL APPROACH THE AREA
TONIGHT INTO SATURDAY. FIRST ROUND OF LOW LEVEL THETAE ADVECTION
PUSHES IN PRETTY QUICKLY THIS AFTERNOON...RESULTING IN AN INCREASE
IN LOW LEVEL CLOUDS. LOOKS LIKE SOME INSTABILITY MIGHT EXIST ABOVE
THIS CLOUD DECK...THUS WOULD NOT BE SURPRISED TO SEE SOME ELEVATED
SCATTERED THUNDERSTORMS BY LATE THIS AFTERNOON INTO THIS
EVENING...MAINLY ACROSS NORTHWEST IOWA. MAIN BATCH OF LOW LEVEL
MOISTURE ADVECTION APPROACHES THE CWA AFTER 06Z AS THE LOW LEVEL JET
GETS GOING...AND THINK THE 06Z TO 12Z TIMEFRAME WILL FEATURE THE
MOST WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY. IT NOW APPEARS
LIKE MOST OF THE ACTIVITY WILL BE SOUTHEAST OF A MARSHALL TO TYNDALL
LINE...AS AREAS NORTHWEST OF THIS WILL HAVE TO DEAL WITH A DRIER
PUSH OF AIR FROM THE WEST. ELEVATED CAPE BETWEEN 500 AND 1000 J/KG
EXPECTED TONIGHT IN THE ABOVE MENTIONED AREAS. THUS THINK WE SHOULD
SEE QUITE A BIT OF THUNDER WITH THE SHOWERS...ALTHOUGH SEVERE
WEATHER IS NOT ANTICIPATED...AS STORMS WILL BE BASED ABOVE THE BEST
WIND SHEAR. PWATS STILL EXPECTED TO BE AROUND 3 STANDARD DEVIATIONS
ABOVE NORMAL...SO COULD SEE SOME HEAVY RAIN IN SOME OF THE
CONVECTION TONIGHT...ALTHOUGH ON AVERAGE MOST AREAS WILL PROBABLY
SEE BETWEEN A QUARTER AND A HALF AN INCH.
SATURDAY IS A BIT MORE TRICKY. ELEVATED ACTIVITY SHOULD EXIT
NORTHWEST IOWA DURING THE MORNING...WITH A DRY SLOT WORKING INTO THE
AREA. MAY EVEN SEE A PERIOD OF PARTLY SUNNY SKIES ALLOWING
TEMPERATURES TO REBOUND INTO THE 60S AND 70S...WARMEST IN OUR SOUTH.
TWO SHOTS FOR PRECIPITATION ON SATURDAY...ONE AHEAD OF THE COLD
FRONT ACROSS MAINLY NORTHWEST IOWA...AND THE OTHER ON THE BACKSIDE
OF THE DEEPENING LOW PRESSURE SYSTEM. MODELS IN DISAGREEMENT ON HOW
THEY HANDLE THE UPPER LEVEL LOW. NAM IS FURTHEST SOUTH AND KEEPS ANY
WRAPAROUND RAIN SATURDAY AFTERNOON AND EVENING WELL TO OUR
SOUTH...WHILE THE ECMWF IS FURTHEST NORTH AND STRONGEST WITH THE
WAVE...GIVING UP TO A HALF AN INCH OF RAIN ACROSS NORTHWEST IOWA
SATURDAY EVENING. FAVOR A SOLUTION IN BETWEEN...CLOSER TO THE GFS
AND GEM...WHICH WOULD KEEP MOST OF THE RAIN SOUTH AND EAST OF THE
AREA...ALTHOUGH WILL HAVE TO CONTINUE TO MONITOR TRENDS.
AS FAR AS SEVERE POTENTIAL WITH THE COLD FRONTAL PASSAGE...WILL
DEPEND ON HOW MUCH SUN WE CAN GET AND THUS HOW UNSTABLE WE GET AHEAD
OF THE FRONTAL PASSAGE. WILL NEED TO HEAT ENOUGH TO BREAK THE
INVERSION...WHICH WILL LIKELY ACT AS A CAP AND MAY INHIBIT
CONVECTION AHEAD OF THE FRONT. ONLY THREAT APPEARS TO BE FROM ABOUT
SIOUX CITY TO JACKSON MINNESOTA...WHERE THE GFS IS MOST UNSTABLE
WITH CAPES AROUND 1500 J/KG...WITH THE NAM AND SREF ARE CLOSER TO
500 J/KG. DEEP LAYER SHEAR SHOULD BE PRETTY IMPRESSIVE WITH VALUES
AROUND 40 TO 50 KTS. STRONGEST UPPER LEVEL SUPPORT SHOULD STAY TO
OUR SOUTH WITH THE MAIN UPPER WAVE...HOWEVER WITH THE TROUGH AXIS
PUSHING ACROSS AT THE SAME TIME AS THE FRONT...STILL SHOULD SEE
DECENT LIFT. SO IF STORMS CAN GET GOING ALONG THE FRONT...EVEN THE
MINIMAL CAPE MIGHT EB ENOUGH TO GET SOME OF THE STRONGER WINDS DOWN
TO THE SURFACE.
LOW PRESSURE PUSHES EAST...LEADING TO A DRY SUNDAY. LOOKS
WARM...ALTHOUGH SOME UNCERTAINTY ON HOW QUICKLY LOW LEVEL THERMAL
PROFILES RECOVER BEHIND THE TROUGH...WITH THE NAM SEVERAL DEGREES
WARMER THAN THE ECMWF AND GFS. EITHER WAY SHOULD SEE 60S OR 70S.
WILL STAY BREEZY BEHIND THE SYSTEM...WITH NORTHWESTERLY WINDS
GUSTING AROUND 20 TO 30 MPH. CURRENTLY EXPECTING RH AROUND 30
PERCENT...SO WHILE RED FLAG CONDITIONS PROBABLY WONT BE MET...FIRE
DANGER WILL STILL BE ELEVATED. /CHENARD
NOT MANY CHANGES NEEDED TO THE ON GOING EXTENDED FORECAST NEXT WEEK.
FAIRLY WAVY PATTERN IS EVIDENT WITH AN UPPER FLOW MOVING ON SHORE
ACROSS THE PACIFIC NORTHWEST. THIS WILL PROVIDE A MILD FLOW OF AIR
FOR OUR REGION ON MONDAY AND TUESDAY...WITH ABOVE NORMAL HIGHS IN
THE 70S. ON WEDNESDAY AND THURSDAY...THERE IS QUITE A BIT OF
DISCREPANCY BETWEEN THE VARIOUS DETERMINISTIC MODELS IN HOW THEY
HANDLE THE NEXT WAVE. THE GEM GLOBAL AND GFS ARE GENERALLY IN BETTER
AGREEMENT IN HOW THEY HANDLE THE MID WEEK SHORT WAVE...AS THEY DIG
IT INTO AN UPPER TROUGH AS IT MOVES EASTWARD ACROSS THE PLAINS. THE
ECMWF IS MORE OR LESS IN ITS OWN CAMP. LEFT SOME SMALL POPS IN FOR
TUESDAY NIGHT AND WEDNESDAY TO ACCOUNT FOR THIS PASSAGE...WITH
COOLER TEMPERATURES ON WEDNESDAY AND THURSDAY.
&&
.AVIATION.../FOR THE 12Z TAF ISSUANCE/
VFR CONDITIONS WILL PREVAIL THIS MORNING...THEN CLOUD CONDITIONS
WILL PROBABLY BEGIN TO DETERIORATE A BIT. ALREADY PLENTY OF STRATUS
IN THE MVFR TO LOWER VFR RANGE EXISTS FROM EXTREME SOUTHERN NEBRASKA
TO POINTS SOUTHWARD. ONCE OUR WINDS TURN TO THE SOUTH AND SOUTHEAST
TODAY...THE STRATUS WILL LIKELY BEGIN A RAPID PUSH NORTHWARD INTO
OUR AREA...PUTTING CONDITIONS INTO THE LOWER VFR TO UPPER END MVFR
CATEGORIES FROM SOUTH TO NORTH THIS AFTERNOON. INTERESTINGLY...A
COUPLE OF MODELS SUCH AS THE NAM AND HRRR STRONGLY SUGGEST THAT A
LOWER END VFR DECK WILL SHOOT NORTHWARD UP THE JAMES VALLEY...
AFFECTING THE KHON TAF SITE WITH SOME STRATUS BEFORE IT AFFECTS THE
KFSD TAF SITE. WILL MONITOR THIS. OTHERWISE MID LEVEL INSTABILITY
AND MOISTURE COULD GIVE AN ISOLATED SHOWER OR THUNDERSTORM IN THE
SIOUX CITY AREA LATE THIS AFTERNOON. BUT LATER TONIGHT IS WHEN THE
BETTER RAIN AND THUNDERSTORM CHANCES BEGIN DUE TO STRONG WARM AIR
ADVECTION AHEAD OF LOW PRESSURE. THE KHON TAF SITE MAY GET MISSED.
BUT MUCH BETTER CHANCES FOR THUNDERSTORMS AND MVFR CONDITIONS EXISTS
FOR THE KFSD AND KSUX TAF SITES LATE TONIGHT. FINALLY CONCERNING
WINDS...SOUTHERLY WINDS WITH GUSTS AT OR ABOVE 25 KNOTS WILL DEVELOP
BY MID TO LATE MORNING...WITH THE STRONGEST WINDS AFFECTING THE KHON
AREA DURING THE AFTERNOON.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
MN...RED FLAG WARNING FROM 1 PM THIS AFTERNOON TO 7 PM CDT THIS
EVENING FOR MNZ900.
NE...NONE.
SD...RED FLAG WARNING FROM 1 PM THIS AFTERNOON TO 7 PM CDT THIS
EVENING FOR SDZ256-257.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
603 AM CDT FRI OCT 12 2012
.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
258 AM CDT FRI OCT 12 2012
MAIN FORECAST CONCERN IS ON SEVERE WEATHER POTENTIAL SATURDAY INTO
SATURDAY NIGHT.
CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A SPLIT FLOW PATTERN ACROSS NORTH AMERICA. IN THE NORTHERN
STREAM...WEAK RIDGING WAS NOTED OVER THE NORTHERN U.S. ROCKIES AND
THEN DOWNSTREAM TROUGHING OVER THE GREAT LAKES. IN THE SOUTHERN
STREAM...AN UPPER LOW WAS OVER SOUTHERN CALIFORNIA WITH RIDGING
BUILDING UP AHEAD OF IT ACROSS THE CENTRAL AND SOUTHERN PLAINS. OVER
THE FORECAST AREA...SATELLITE IMAGERY SHOWED SKIES HAVE CLEARED OUT
THANKS TO SUBSIDENCE AND DRYING IN THE WAKE OF THE GREAT LAKES
TROUGHING. ALSO REFLECTED OF THE SUBSIDENCE IS A 1030MB SURFACE HIGH
CENTERED NEAR MINNEAPOLIS. PRECIPITABLE WATER VALUES WERE QUITE DRY
ON THE 00Z MPX SOUNDING...0.17 INCHES OR 30 PERCENT NORMAL. SURFACE
DEWPOINTS ALSO REFLECTIVE OF THE DRYING...DOWN IN THE TEENS TO LOWER
20S. DECENT AMOUNT OF COLD AIR ACCOMPANYING THE SURFACE HIGH WITH
850MB TEMPS THAT DROPPED TO -4C AT MPX AT 00Z COMPARED TO +3C 12
HOURS EARLIER. TO THE SOUTH...A STATIONARY FRONTAL BOUNDARY WAS
POSITIONED FROM OKLAHOMA INTO THE OHIO RIVER VALLEY. SOUTH OF THIS
FRONT...PLENTIFUL MOISTURE WAS NOTED WITH SURFACE DEWPOINTS IN THE
MID 60S TO LOWER 70S ACROSS OKLAHOMA AND MUCH OF TEXAS. 00Z FORT
WORTH SOUNDING HAD A PRECIPITABLE WATER VALUE OF 1.6 INCHES OR 176
PERCENT OF NORMAL. 850MB PROFILER AND VWP DATA CURRENTLY SHOWS MUCH
OF THIS MOISTURE BEING ADVECTED INTO AND ALONG THE STATIONARY
FRONTAL BOUNDARY.
TODAY AND TONIGHT...MAJOR CHANGES LOOK TO OCCUR IN THE WEATHER
PATTERN ACROSS THE FORECAST AREA DURING THIS TIME. THE UPPER LOW IN
CALIFORNIA MODELS ARE ALL IN GOOD AGREEMENT LIFTING IT OUT INTO
NORTHEAST COLORADO BY 12Z SATURDAY. IN RESPONSE TO THIS EJECTION THE
SUBTROPICAL RIDGING BUILDING OVER THE CENTRAL AND SOUTHERN PLAINS
GETS PULLED NORTHWARD INTO THE FORECAST AREA. AS A RESULT...THIS
HIGH PRESSURE BUILDING INTO THE FORECAST AREA RIGHT NOW AT THE
SURFACE WILL NOT HANG AROUND LONG. IN FACT...BY 00Z...15-20
SOUTHERLY 925MB WINDS ARE PROGGED AS THE HIGH SHIFTS OVER LAKE ERIE.
WE SHOULD SEE PLENTY OF SUN TODAY BEING UNDER THE INFLUENCE OF DRY
AIR NOTED ON THE 00Z MPX SOUNDING. 850MB TEMPS AT 18Z AROUND 1C IN
NORTHEAST IOWA TO -4C IN TAYLOR COUNTY SUGGESTS HIGHS FROM THE UPPER
40S TO MID 50S...COOLEST AS EXPECTED IN TAYLOR COUNTY. THINGS GET A
LITTLE MORE INTERESTING TONIGHT AS 850MB MOISTURE TRANSPORT KICKS
INTO HIGH GEAR AHEAD OF THE EJECTING UPPER LOW. 850MB WINDS
THEMSELVES ARE PROGGED TO INCREASE TO 35 TO 50 KT FROM THE SOUTHERN
PLAINS INTO THE FORECAST AREA BY 06Z...HELPING TO BRING UP THE
MOISTURE CURRENTLY SEEN ACROSS OKLAHOMA AND TEXAS. THIS RAPID
INCREASE IN MOISTURE WILL LEAD TO PRECIPITATION DEVELOPMENT...
PERHAPS AS EARLY AS 03Z AS SUGGESTED BY THE 12.00Z NAM. MORE LIKELY
IS TO HAVE WIDESPREAD SHOWERS ACROSS THE FORECAST AREA AFTER 06Z.
THUNDERSTORMS ARE ALSO EXPECTED WITH THIS ACTIVITY WITH MODELS
SHOWING UPWARDS OF 600 J/KG OF MUCAPE...MOSTLY ROOTED AT OR ABOVE
850MB PER CROSS-SECTIONS...ACCOMPANYING THE MOISTURE TRANSPORT. IN
ADDITION TO THE MOISTURE ADVECTION...850MB TEMPS ARE GOING TO SHOOT
UP...REACHING AROUND 12C BY 12Z. AS SUCH...ANTICIPATING LOWS IN THE
EVENING WITH TEMPERATURES RISING THEREAFTER.
SATURDAY AND SATURDAY NIGHT...THIS PERIOD HAS BEEN INTERESTING TO
WATCH OVER THE PAST SEVERAL DAYS WITH RESPECT TO WHAT HAPPENS WITH
THE UPPER LOW. ALL MODELS EXCLUDING THE NAM HAVE HAD ISSUES WITH THE
TRACK AND SPEED. HOWEVER...THERE IS A STRONG CONSENSUS NOW THAT THIS
UPPER LOW IS GOING TO TRACK EAST INTO SOUTHERN IOWA BY 12Z SUNDAY
AND TAKE ON A NEGATIVE TILT. MUCH OF THIS IS CAUSED BY A POTENT
SHORTWAVE HANGING BACK FROM THE UPPER LOW CROSSING THE SOUTHERN
PLAINS. THIS HAS BIG IMPLICATIONS FOR THE FORECAST AREA AS IT
DICTATES THE TRACK OF THE BEST PV ADVECTION...WHICH NOW STAYS MOSTLY
SOUTH OF THE AREA UNTIL MAYBE 12Z SUNDAY SOUTH OF I-90. STILL...
THERE IS PLENTY OF FORCING FOR PRECIPITATION. ON SATURDAY...THE
FORCING REMAINS THAT PERSISTENT STRONG 850MB MOISTURE TRANSPORT ZONE
WITH THE NOSE INTO THE FORECAST AREA. NOTE THAT THE ZONE DOES SLOWLY
SHIFT EAST IN RESPONSE TO THE APPROACHING UPPER LOW. AS SUCH...
PRECIPITATION MAY DIMINISH IN THE AFTERNOON ACROSS MINNESOTA.
PERSISTENT ADVECTION OF INSTABILITY WITHIN THE MOISTURE TRANSPORT...
WHICH SHOULD INCREASE THROUGH THE DAY AS THE AIRMASS SOUTH OF THE
AREA HEATS UP...SUGGESTS QUITE A BIT OF THUNDERSTORM ACTIVITY. BY
21Z AND CONTINUING THROUGH THE EVENING...500-1000 J/KG OF MUCAPE IS
PROGGED OVER THE FORECAST AREA...HIGHEST SOUTH OF I-90.
PRECIPITATION OVERALL LOOKS PRETTY GOOD FOR MOST OF THE AREA
SATURDAY NIGHT TOO...DUE TO A COMBINATION OF INCREASING LOW TO MID
LEVEL FRONTOGENESIS AND RIGHT ENTRANCE REGION SUPPORT FROM AN UPPER
JET DEVELOPING OVER UPPER MICHIGAN. NORTHWEST SECTIONS OF THE AREA
COULD BE ON THE EDGE OF THE PRECIPITATION... THOUGH...AS INDICATED
BY THE 12.00Z NAM AND AS SUCH SLIGHT LOWER CHANCES ARE PRESENT
THERE. GENERALLY FOLLOWED A BLEND OF GUIDANCE FOR HIGHS AND LOWS.
ONE SIDE NOTE WHICH REFLECTS THE CHANGE IN AIRMASSES...MOST
LOCATIONS WILL SEE A DEWPOINT JUMP OF 30 TO 40 DEGREES IN 24 HOURS
BETWEEN 21Z TODAY AND 21Z SATURDAY.
SEVERE WEATHER POTENTIAL FOR SATURDAY INTO SATURDAY NIGHT...ALTHOUGH
THE 500-1000 J/KG OF CAPE IN THE AFTERNOON AND EVENING IS THIN...
EXTENDING UP TO AN EQUILIBRIUM LEVEL AROUND 250MB...THE
ENVIRONMENT FOR THE MOST PART IS UNCAPPED IN THE WARM SECTOR AHEAD
OF A SURFACE LOW COMING ACROSS NORTHERN IOWA. WARM SECTOR LOOKS TO
BE SITUATED MOSTLY SOUTH OF I-90. COMBINE THIS CAPE WITH A HIGHLY
SHEARED ENVIRONMENT NOTED BY 0-6KM SHEAR OF 40-50KT AND 0-1KM
SHEAR AROUND 25 KT YIELDS CONCERN OF DISCRETE TORNADIC SUPERCELLS
IN THE WARM SECTOR. HODOGRAPHS SUGGEST STRONGLY DOMINANT RIGHT
MOVING SUPERCELLS. DAMAGING WINDS WOULD BE A CONCERN TOO GIVEN THE
SHEAR. THIN CAPE PLUS RELATIVELY HIGH FREEZING LEVELS FOR THIS
TIME OF YEAR (AROUND 11000 FT) SHOULD PRECLUDE MUCH OF A LARGE
HAIL HAZARD. OVERALL...HIGHER SEVERE THREAT SHOULD EXIST SOUTH OF
THE FORECAST AREA WHERE CAPE AND DYNAMIC FORCING IS GREATER.
SWODY2 SEVERE WEATHER PROBABILITIES DEPICT THIS WELL. IT SHOULD BE
STRESSED THAT ANY UNEXPECTED SUNSHINE ON SATURDAY COULD
DRAMATICALLY INCREASE THE SEVERE WEATHER POTENTIAL. PRESENT
FORECASTS PORTRAY A MORE LIKELY CLOUDY SCENARIO.
SUNDAY AND SUNDAY NIGHT...MODELS ARE PRETTY QUICK IN EJECTING THE
NEGATIVE TILT SHORTWAVE AND THE ASSOCIATED SURFACE SYSTEM AWAY FROM
THE AREA. BY 00Z MONDAY...BOTH FEATURES SHOULD BE NEAR LAKE HURON.
THEREFORE...AFTER SOME DEFORMATION PRECIPITATION ON THE BACK SIDE OF
THE SYSTEM AFFECTS THE AREA IN THE MORNING...ESPECIALLY ACROSS
WISCONSIN...ANTICIPATING CONDITIONS TO DRY OUT FOR THE AFTERNOON.
UPPER TROUGHING DOES LINGER OVER THE AREA THROUGH SUNDAY NIGHT...
AIDED BY A FEW PACIFIC SHORTWAVES DROPPING IN BEHIND THE NEGATIVELY
TILTED SHORTWAVE. HOWEVER...AT MOST IT LOOKS LIKE THESE WOULD BRING
CLOUDS. DESPITE BEING IN COLD ADVECTION IN THE WAKE OF SUNDAYS
SYSTEM...850MB TEMPS ONLY FALL TO 2-4C. COMBINE THIS WITH SOME
AFTERNOON SUN SHOULD BOOST HIGHS INTO THE MID 50S TO LOW
60S...WARMEST WEST OF THE MISSISSIPPI RIVER WHERE THE MOST SUN IS
EXPECTED. COULD BE A COOL NIGHT SUNDAY NIGHT WITH A SURFACE RIDGE
BUILDING IN...BUT IT WILL ALL DEPEND ON THE CLOUDS. HAVE LEANED
TOWARDS A BLEND OF GUIDANCE WITH A KNOCK DOWN IN TEMPS FOR THE
TYPICAL COOLER SPOTS. MAY HAVE TO KEEP AN EYE ON VALLEY FOG
POTENTIAL IF THE SURFACE RIDGE BUILDS IN A LITTLE FASTER AND SKIES
STAY MOSTLY CLEAR.
.LONG TERM...MONDAY THROUGH THURSDAY NIGHT
258 AM CDT FRI OCT 12 2012
12.00Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES PORTRAY YET ANOTHER
PATTERN CHANGE DURING THE LONG TERM PERIOD...FORECASTING TROUGHING
ACROSS THE NORTHERN PLAINS INTO THE WESTERN GREAT LAKES BY THURSDAY.
THIS IS SIMILAR TO WHAT WE HAVE JUST EXPERIENCED FOR THE PAST
WEEK...THOUGH THE AIR IN THE TROUGH IS NOT NEARLY AS COOL.
THE PERIOD BEGINS WITH A FAST WEST-NORTHWEST FLOW FROM THE PACIFIC
NORTHWEST INTO THE NORTHERN PLAINS. THERE ARE INDICATIONS OF A
SHORTWAVE RIDING THROUGH THIS FLOW AND AMPLIFYING A TROUGH OVER THE
NORTHERN PLAINS ON TUESDAY...CAUSING RIDGING TO DEVELOP OVER THE
FORECAST AREA. THUS...IT WOULD APPEAR MONDAY AND IN PARTICULAR
TUESDAY SHOULD BE THE WARM DAYS OF THE WEEK. 850MB TEMPS CLIMB TO
6-9C BY 00Z TUESDAY AND 8-11C BY 00Z WEDNESDAY. MAY NOT BE ABLE TO
REALIZE THE FULL WARMTH ON TUESDAY...THOUGH...AS WARM ADVECTION AND
DPVA FORCED CLOUDS AND PRECIPITATION SPREAD INTO THE AREA AHEAD OF
THE NORTHERN PLAINS TROUGH. THE NORTHERN PLAINS TROUGH IS THEN
SUGGESTED TO SHIFT EAST OVER THE AREA FOR WEDNESDAY INTO THURSDAY.
KEPT PRECIPITATION CHANCES GOING FOR WEDNESDAY INTO WEDNESDAY NIGHT
PER CONSENSUS...DUE TO A DECENT STRENGTH SHORTWAVE SUGGESTED TO DROP
INTO THE TROUGH. AS THE SHORTWAVE PUSHES OFF TO THE EAST FOR
THURSDAY...FOLLOWED A DRY FORECAST. AGAIN...TEMPERATURES WILL COOL
DOWN WEDNESDAY INTO THURSDAY AS 850MB TEMPS DROP TO 4-6C AND 2-4C
RESPECTIVELY. AFTER MONDAY THROUGH WEDNESDAY PROGGED TO MAINLY BE IN
THE 60S...THURSDAY LOOKS TO END UP THE 50S.
&&
.AVIATION...TODAY AND TONIGHT
603 AM CDT FRI OCT 12 2012
HIGH PRESSURE WILL BRING VFR CONDITIONS TO THE TAF SITES THROUGH
EARLY THIS EVENING. PLAN ON LIGHT AND VARIABLE WINDS THROUGH
MIDDAY...BEFORE THE HIGH SLIDES EAST AND LOW PRESSURE DEEPENS OVER
THE CENTRAL PLAINS. WINDS WILL BECOME SOUTH THIS AFTERNOON AT 8 TO
13 KTS. CLOUDS WILL BE ON THE INCREASE THIS EVENING AS A STRONG
LOW PRESSURE SYSTEM DEEPENS OVER THE CENTRAL PLAINS AND LIFTS
NORTHEAST INTO THE UPPER MISSISSIPPI RIVER VALLEY. SHOWERS AND
THUNDERSTORMS WILL OVERSPREAD THE TAF SITES AFTER 06Z TONIGHT.
PLAN ON CLOUD BASES LOWERING INTO THE 2 TO 3 KFT RANGE LATE
TONIGHT...WITH IFR CEILINGS POSSIBLE IN HEAVIER SHOWERS AND
STORMS. IN ADDITIONS...VISIBILITIES MAY BE REDUCED TO AROUND 4 SM
IN THE HEAVIER DOWNPOURS. WILL HAVE TO KEEP A CLOSE WATCH ON LOW
LEVEL WIND SHEAR TONIGHT. FORECAST SOUNDINGS SHOW WINDS
INCREASING TO AROUND 40 KTS AT 2KFT BY 03Z. IT APPEARS THAT
SURFACE WINDS WILL STAY IN THE 13 TO 17 KT RANGE OVERNIGHT...WITH
WINDS HOLDING JUST BELOW LOW LEVEL WIND SHEAR CRITERIA. PLAN ON
SHOWERS AND THUNDERSTORMS THROUGH MUCH OF THE DAY ON SATURDAY.
SOME OF THE STORMS MAY BECOME SEVERE WITH DAMAGING WINDS AND HEAVY
RAINFALL...MAINLY SOUTH OF INTERSTATE 90.
&&
.HYDROLOGY...TONIGHT THROUGH SUNDAY
258 AM CDT FRI OCT 12 2012
QPF WISE FOR THE TONIGHT THROUGH SUNDAY MORNING SYSTEM...REALLY HARD
TO SAY. THE MAXIMUM AREA SHOULD BE OVER THE SOUTHEASTERN 1/3 OF THE
FORECAST AREA...WHERE THE LONGEST PERIOD OF 850MB MOISTURE TRANSPORT
NOSES IN AND THEN GETS HIT BY THE DEFORMATION ON THE BACK SIDE OF
THE SYSTEM. PRECIPITABLE WATER VALUES CLIMB TO AROUND 1.5 INCHES OR
200-250 PERCENT OF NORMAL TONIGHT AND HOVER AROUND THERE INTO SUNDAY
MORNING. POTENTIAL IS DEFINITELY THERE TO GET 1 TO 2 INCHES FOR THE
ENTIRE TIME PERIOD...AS SUGGESTED BY HPC FORECASTS AND SREF
PROBABILITIES...WITH LOCALLY HIGHER AMOUNTS DUE TO THE CONVECTIVE
NATURE. IN FACT...THE LATEST 12.00Z ECMWF HAS UPWARDS OF 3-3.5
INCHES. THE LANDSCAPE AND RIVERS REALLY COULD USE THIS RAIN GIVEN
THE SEVERE TO EXTREME DROUGHT CONDITIONS IN PLACE. THEREFORE...NO
FLOODING IS ANTICIPATED.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
258 AM CDT FRI OCT 12 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...WETENKAMP
HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
1037 AM PDT FRI OCT 12 2012
.DISCUSSION...AS OF 9:00 AM PDT FRIDAY...FEW LIGHT SHOWERS THIS
MORNING HAVE BASICALLY COME TO AN END. RAINFALL AMOUNTS HAVE BEEN
VERY LIGHT WITH SPOTS THAT PICKED UP ANY RAIN REPORTING LESS THAN
A TENTH OF AN INCH. PLENTY OF CLOUDS ACROSS OUR AREA ALTHOUGH
UNLIKE YESTERDAY CIG HEIGHTS ARE HIGHER AND MORE BREAKS NOTED...SO
HOPEFULLY WE WILL SEE MORE SUNSHINE BY THE AFTERNOON.
SYNOPTICALLY...THE MAIN STORY WILL BE A RIDGE OF HIGH PRESSURE
THAT WILL BUILD ACROSS CALIFORNIA STARTING THIS WEEKEND AND GOING
INTO NEXT WEEK AS A REX BLOCK. THIS WILL HELP TO BRING SEVERAL DAYS OF
GENERALLY SUNNY CONDITIONS WITH HIGHS GOING BACK TO ABOVE NORMAL
LEVELS. ONLY REAL FORECAST CONCERNS IS HOW MUCH OVERNIGHT
CLOUDS/PATCHY FOG WE WILL SEE PLUS HOW WARM IT WILL BECOME. AT
LEAST ONE DAY OF WIDESPREAD 80S AND 90S LOOK LIKELY FOR INTERIOR
SPOTS DURING THE SECOND HALF OF NEXT WEEK.
.PREVIOUS DISCUSSION...LIGHT RAIN SHOWERS CONTINUE MAINLY FROM
THE SAN FRANCISCO BAY SOUTHWARD THIS MORNING. IN THE LAST 3
HOURS...MUSTANG RIDGE IN MONTEREY COUNTY RECEIVED 0.08" WHILE THE
OAKLAND SOUTH RAWS RECEIVED 0.02" IN THAT SAME TIME FRAME. THE NAM
AND HRRR SEEM TO HAVE THE BEST HANDLE OF THE CURRENT SYNOPTIC
PATTERN...AND BOTH KEEP SCATTERED SHOWERS IN THE REGION THROUGH AT
LEAST 15Z. POPS WERE SIGNIFICANTLY INCREASED BETWEEN 12Z AND 18Z
TO ACCOUNT FOR THESE SHOWERS.
SKIES WERE CLOUDY OVERNIGHT...AS ABUNDANT MID AND LOW LEVEL
MOISTURE PREVAILED OVER THE REGION. TEMPERATURES SO FAR FELL INTO
THE 50S...SIMILAR TO THOSE OBSERVED LAST NIGHT. LOW CLOUDS WILL BE
LATE TO DISSIPATE AGAIN TODAY...AND A FEW PLACES MIGHT ONLY SEE
GLIMPSES OF BLUE SKY.
OTHERWISE...THE UPPER LEVEL LOW OVER SOUTHERN CALIFORNIA IS
FORECAST TO MOVE SLOWLY EAST NORTHEAST TOWARD SOUTHERN NV AND
NORTHERN AZ BY THIS AFTERNOON. THIS WILL RESULT IN DRY...BUT COOL
CONDITIONS OVER THE REGION. WHILE THE LOW MOVES EAST...AN UPPER
LEVEL SHORT WAVE WILL SKIRT NORTHERN CALIFORNIA...BRINGING A
SLIGHT CHANCE OF SHOWERS TO FAR NORTHERN SONOMA COUNTY.
HOWEVER...THE SHORT TERM MODELS KEEP BACKING OFF WITH REGARDS TO
PRECIPITATION WITH THIS DISTURBANCE...SO CONFIDENCE IS LOW THAT WE
WILL SEE ANY RAIN IN THIS REGION.
WEAK UPPER LEVEL RIDGING WILL BEGIN TO BUILD OVER THE REGION
DURING THE SECOND HALF OF THE WEEKEND. THIS WILL RESULT IN A
SIGNIFICANT WARMING TREND THROUGH THE AREA...WITH TEMPERATURES
NEARING NEAR NORMAL READINGS FOR THE MIDDLE OF OCTOBER.
EVEN MORE SIGNIFICANT WARMING IS FORECAST FOR THE MIDDLE OF NEXT
WEEK...WITH A 588 DM RIDGE NEARING CENTRAL CALIFORNIA. 850 MB
TEMPERATURES ARE FORECAST TO RISE OVER 11 DEGREES C BETWEEN THIS
AFTERNOON AND WEDNESDAY AFTERNOON. THIS WILL RESULT IN INLAND
TEMPERATURES REACHING THE 80S TO LOW 90S...WHILE THE COASTAL
LOCATIONS REACH THE UPPER 60S TO 70S.
THE CLIMATE PREDICTION CENTERS 6 TO 10 DAY OUTLOOK CALLS FOR
TEMPERATURES WELL ABOVE NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION...AS OF 10:30 AM FRIDAY...DEFINITELY A LOW CONFIDENCE
FORECAST KINDA A DAY. BAY AREA OBS AND VISIBLE SATELLITE BOTH
INDICATE A MIX OF LOW STRATUS AND MID LEVEL CONVECTIVE CLOUDS.
THAT BEING SAID...GIVEN THE AMOUNT OF LINGERING MOISTURE AND
NEARBY SHOWERS(E OF CWA) HAVE KEEP MANY TERMINALS HIGH END MVFR TO
LOW END VFR THROUGH THE DAY. WOULD NOT BE SURPRISED IS SOME
TERMINALS FLIP FLOP FROM VFR TO MVFR AND VICE VS AROUND THE 3K FOOT
LEVEL. ONE INTERESTING THING TO MONITOR IS THE DRY SLOT SEEN ON
VIS OVER THE OCEAN. IF THIS AREA EXPANDS AND MOVES E TAFS WILL
NEED AMENDING. FOR TONIGHT...WILL BRING CIGS BACK IN THE 1-2K FOOT LEVEL.
.VICINITY OF KSFO...WILL KEEP MVFR CIGS THROUGH MUCH OF THE
AFTERNOON. WILL ALLOW FOR OCCASIONAL VFR CIGS COVERED BY TEMPO GROUPS.
EARLY RETURN POSSIBLE.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO WITH A MIX OF MVFR TO VFR
THROUGH THE DAY.
MONTEREY BAY AREA TERMINALS...MVFR CIGS THROUGH MUCH OF THE DAY.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
&&
$$
PUBLIC FORECAST: BELL/RILEY
AVIATION/MARINE: MM
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AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
236 PM EDT FRI OCT 12 2012
.PREV DISCUSSION... /ISSUED 758 AM EDT FRI OCT 12 2012/
PREV DISCUSSION... /ISSUED 513 AM EDT FRI OCT 12 2012/
UPDATE...
MCS TRACKING SOUTHEASTWARD ACROSS CENTRAL TN SHOULD BEGIN TO
INFLUENCE NORTHERN GEORGIA FROM THE NW AS EARLY AS 11Z. SCATTERED
THUNDERSTORM DEVELOPMENT HAS BEEN PERSISTENT OVERNIGHT AND BASED
ON RAP ANALYSIS OF MUCAPE...COMPLEX HAS BEEN RIDING ALONG AN
ELEVATED INSTABILITY AXIS. IT IS STILL EXPECTED TO BECOME LESS
ORGANIZED AND DISSIPATE MOSTLY AFTER 15Z...THOUGH HAVE INCLUDED
ISOLATED TO SCATTERED THUNDER ACROSS PARTS OF THE NORTH. BEST
CHANCE FOR ANY THUNDERSTORMS SHOULD STAY NORTH OF ATLANTA AND
EVENTUALLY BECOME MORE ISOLATED IN COVERAGE INTO MID MORNING. THE
MAIN THREATS WITH ANY THUNDERSTORM WILL BE OCCASIONAL
LIGHTNING...GUSTY WINDS...AND HEAVY RAINFALL. PREVIOUS DISCUSSION
FOLLOWS...
BAKER
PREV DISCUSSION... /ISSUED 420 AM EDT FRI OCT 12 2012/
SHORT TERM /TODAY THROUGH SATURDAY/...
CLOUD DECK AND VERY ISOLATED SHOWER DEVELOPMENT ADVECTING INTO
NORTHERN GEORGIA EARLY THIS MORNING HAS LIMITED RADIATIONAL COOLING
SO HAVE THUS RAISED MIN TEMPS BY A FEW DEGREES. MCS CURRENTLY ACROSS
WESTERN KY AND FAR NORTHWESTERN TN IS TRACKING SOUTHEASTWARD IN
ASSOCIATION WITH SOUTHERN EXTENT OF LOW AMPLITUDE UPPER SHORTWAVE
TROUGH. THERE IS A SLIM CHANCE THAT SOME ISOLATED THUNDER COULD
REACH INTO THE FAR NORTHEASTERN PORTION OF THE AREA SHORTLY BEFORE
12Z WITH THE MCS REMNANTS...HOWEVER PROGGED MUCAPE STAYS LOW AND RAP
ANALYSIS HAS COMPLEX TRACKING INTO A MORE STABLE ENVIRONMENT SO WILL
LEAVE CHANCE POPS FOR SHOWERS THROUGH MORNING. HOWEVER...WILL
CLOSELY MONITOR PROGRESSION OF THIS SYSTEM AND UPDATE AS SEEN FIT.
SUITE OF SHORT RANGE MODEL SOLUTIONS GENERALLY AGREE WITH PRECIP
ACROSS NW GEORGIA MAINLY FROM 10-15Z...THOUGH LOOKS TO BE LIMITED IN
COVERAGE AND GREATLY TAPERS OFF INTO THE AFTERNOON AS THE BEST UPPER
LEVEL DYNAMICS STAY REMOVED FROM THE MOISTURE AND WELL NORTH OF THE
REGION. WILL THEREFORE CARRY CHANCE POPS INITIALLY NW TO SLIGHT POPS
BY AFTERNOON AND FURTHER SOUTH INTO WESTERN CENTRAL GEORGIA.
INSTABILITY CONTINUES TO BE LIMITED SO WILL STILL ONLY HAVE SHOWER
POTENTIAL THROUGH AFTERNOON.
CLASSIC CAD EVENT SETS UP FOR SATURDAY WITH 1033-MB PARENT SFC HIGH
PROGGED TO BE CENTERED OVER NEW ENGLAND/MID ATLANTIC REGION BY 12Z.
RESULTANT WEDGE SHOULD LIMIT MAX TEMPS FROM NEAR 70 DEGREES IN THE
NORTHEAST PORTION TO NEAR 80 IN THE SOUTH. GENERALLY A BLEND OF
BIASED CORRECTED MET AND MAV GUIDANCE LOOKED REASONABLE FOR PROGGED
TEMPS THROUGH PERIOD.
BAKER
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
EXTENDED PERIOD BEGINS WITH A SHORTWAVE MOVING THROUGH THE
MISSOURI VALLEY NORTHEAST INTO THE OHIO VALLEY. TRAILING RESIDUAL
ENERGY WILL PUSH INTO THE AREA SUNDAY NIGHT INTO MONDAY WITH A
BROKEN LINE OF SHOWERS AND EMBEDDED THUNDERSTORMS THE RESULT.
INSTABILITY SUFFICIENT FOR STORM DEVELOPMENT BUT MOST SIGNIFICANT
SHEAR LIFTS NORTH OF THE AREA SO EXPECTING NOTHING SIGNIFICANT
LOCALLY AT THIS POINT. HIGH PRESSURE WILL THEN BUILD IN BEHIND THE
FRONT BUT LARGELY ZONAL FLOW WILL KEEP TEMPS ELEVATED THROUGH MID
WEEK.
EXTENDED GUIDANCE COMING INTO BETTER AGREEMENT WRT NEXT MAJOR
SYSTEM SLATED FOR THU. MAIN LOW TO LIFT WELL NORTH OVER THE GREAT
LAKES REGION BUT UPPER TROUGH EXTENDS WELL INTO THE GULF AND WITH
A SPLIT FLOW PATTERN AT THE JET STREAM LEVEL...MODELS HAVE NO
TROUBLE GENERATING PRECIP AREAWIDE. WILL HOLD AT HIGH END CHANCE
FOR NOW THIS FAR OUT AND THE FACT THAT THIS IS THE FIRST RUN
MODELS HAVE SHOWN THIS TYPE OF CONSENSUS.
DEESE
&&
.AVIATION...
18Z UPDATE...
MID TO HIGH LEVEL CLOUDS OVER THE AREA BUT THEY ARE SCT OUT AND
LIFTING THROUGH THIS EVENING. MAY SEE SOME SCT TO BKN CLOUDS
FORMING ACROSS THE AREA OVER NIGHT IN THE 4000FT RANGE BUT NOTHING
THAT WOULD CAUSE ANY AVIATION CONCERNS. WINDS ARE STILL OUT OF
THE NW BUT THEY WILL BE TURNING TO THE NE AND THEN EAST THROUGH
SAT AFTERNOON. WINDS SPEEDS ARE IN THE 8-12KT RANGE NOW BUT THEY
WILL DIMINISH AFTER SUNSET. WINDS WILL PICK BACK UP AGAIN SAT. NO
PRECIPITATION OR RESTRICTIONS TO VSBYS EXPECTED.
//ATL CONFIDENCE...18Z UPDATE...
CONFIDENCE HIGH ON ALL ELEMENTS.
01
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 78 53 73 50 / 20 5 5 0
ATLANTA 79 57 73 56 / 20 5 5 0
BLAIRSVILLE 69 48 69 47 / 30 0 0 5
CARTERSVILLE 77 52 74 52 / 30 5 0 5
COLUMBUS 85 60 81 60 / 20 5 0 0
GAINESVILLE 74 54 71 52 / 30 5 5 0
MACON 83 56 80 53 / 10 5 5 0
ROME 76 52 78 51 / 30 0 0 5
PEACHTREE CITY 79 55 77 51 / 20 5 5 0
VIDALIA 84 60 79 59 / 5 0 0 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...01
LONG TERM....31
AVIATION...01
AREA FORECAST DISCUSSION
NWS GOODLAND KS
244 PM MDT FRI OCT 12 2012
.SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY)
ISSUED AT 1245 PM MDT FRI OCT 12 2012
LATEST THINKING IS THERE WILL BE TWO POTENTIAL ROUNDS OF
PRECIPITATION ASSOCIATED WITH THE LARGE UPPER LOW OVER SOUTHERN
NEVADA THAT WILL AFFECT THE REGION IN THE NEXT 18 HOURS. FIRST...A
SHORT WAVE TROUGH CURRENTLY LIFTING NORTHEAST ACROSS THE OKLAHOMA
PANHANDLE WILL INITIATE SHOWERS AND ISOLATED THUNDERSTORMS THIS
AFTERNOON FROM SOUTHWEST TO NORTHEAST BETWEEN ABOUT 20Z AND 01Z.
THE NAM SHOWS DECENT ELEVATED CAPE AROUND 1000 J/KG HOWEVER 0-6 KM
BULK SHEAR IS ONLY ABOUT 25 KTS THIS AFTERNOON. SUB-SEVERE HAIL
AND C-G LIGHTNING ARE THOUGHT TO BE THE MAIN THREATS. THIS FIRST
ROUND OF PRECIP SHOULD BEGIN TO WEAK AND LOSE COVERAGE AS THE
UPPER TROUGH LIFTS FURTHER NORTHEAST AFTER 00Z. ONE MODULATING
INFLUENCE THIS AFTERNOON IS POSITION OF 250 MB JET. THE CURRENT
LOCATION PUTS OUR AREA IN THE RIGHT EXIT REGION WHICH MAY EXPLAIN
THE LOOK OF THE HRRR REFLECTIVITY FIELDS LATER THIS AFTERNOON
WITH PRECIPITATION SPLITTING AND WEAKENING.
THE BULK OF THE SYSTEM IS EXPECTED TO APPROACH THE AREA OVERNIGHT...
BUT THINK BETTER CHANCES OF SHOWERS AND THUNDERSTORMS WILL BE IN
THE SOUTHEAST COUNTIES IN THE 06-12Z TIME FRAME. THE NAM SHOWS
SOME CAPE IN THE -10 TO -20 C HAIL GROWTH REGION AT THAT TIME,
PLUS 0-6 KM SHEAR WILL INCREASE TO AROUND 70 KTS INDICATING A FEW
STORMS OVERNIGHT HAVE THE POTENTIAL TO PRODUCE SEVERE HAIL IF
THINGS COME TOGETHER AS PLANNED. ALSO KEPT MENTION OF AREAS OF FOG
OVERNIGHT WITH LOW LEVEL RH VALUES ABOVE 95 PERCENT.
ON SATURDAY...SOMEWHAT LESS CERTAIN REGARDING POTENTIAL FOR
SCATTERED SHOWERS DURING THE AFTERNOON. LAPSE RATES NOT ALL THAT
STEEP AS UPPER SYSTEM MOVES OVERHEAD...AND SUBSIDENCE BEHIND UPPER
TROUGH WITH RIDGING MOVING IN WILL COINCIDE WITH PEAK HEATING. KEPT
SLIGHT CHANCES FOR SHOWERS GOING FOR NOW BUT CONFIDENCE IS NOT THAT
HIGH FOR DECENT COVERAGE IF LATEST NAM-GFS VERIFY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 240 PM MDT FRI OCT 12 2012
THE CLOSED LOW THAT BROUGHT PRECIP WILL EXIT THE AREA EARLY SATURDAY
EVENING. MODELS PLACE PRECIP WELL WEST OF THE LOW WHERE A SHORT
WAVE RIDGE WILL BE. AM THINKING IF ANY PRECIP WILL DEVELOP IT
WILL BE JUST BEHIND THE CLOSED LOW. AM NOT TOO CONFIDENT THERE
WILL BE ANY PRECIP ACCOMPANYING THE CLOSED LOW AS IT MOVES EAST
DUE TO 700-500MB LAPSE RATES LESS THAN 6C/KM. HOWEVER WITH MODELS
SHOWING PRECIP FOLLOWING THE CLOSED LOW...WILL KEEP THE MENTION OF
SLIGHT CHANCES GOING DURING THE EARLY EVENING AS THE LOW EXITS THE
AREA.
SUNDAY AND SUNDAY NIGHT AN UPPER LEVEL RIDGE WILL BUILD OVER THE
INTERMOUNTAIN WEST...EXTENDING OVER THE TRI-STATE AREA. A MINOR
SHORT WAVE TROUGH WILL MOVE THROUGH THE FLOW OVER THE NORTHEAST PART
OF THE AREA. HOWEVER WITH LITLE MOISTURE TO WORK WITH...AM NOT
EXPECTING ANYTHING MORE THAN A FEW CLOUDS TO DEVELOP. BEHIND THE
SHORT WAVE TROUGH WINDS WILL INCREASE DURING THE AFTERNOON...WITH
GUSTS NEAR 30MPH AS STRONG WINDS ABOVE THE SURFACE MIX DOWN.
TEMPERATURES FOR SATURDAY THROUGH SUNDAY NIGHT WILL BE NEAR NORMAL.
FOR MONDAY THROUGH FRIDAY THE PERIOD WILL BE PRIMARILY DRY. TUESDAY
AND WEDNESDAY A SHORT WAVE TROUGH MOVES THROUGH THE FLOW OVER THE
AREA...WITH A COLD FRONT FOLLOWING THE FIRST SHORT WAVE TUESDAY
NIGHT. THERE IS SOME MOISTURE TO WORK WITH...SO HAVE INCLUDED
SLIGHT CHANCES FOR THE FAR NORTHEAST PART OF THE AREA TUESDAY
NIGHT. ANOTHER STRONGER COLD FRONT MOVES THROUGH WEDNESDAY NIGHT.
THERE IS LESS MODEL AGREEMENT WITH PRECIP DEVELOPING AS THE SECOND
COLD FRONT MOVES THROUGH...SO WILL CONTINUE WITH THE DRY FORECAST.
TEMPERATURES THROUGH THIS PERIOD WILL BE ABOVE NORMAL PRIOR TO THE
FIRST COLD FRONT THEN NEAR NORMAL THROUGH THE REST OF THE WEEK
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY MORNING) ISSUED
AT 1245 AM MDT FRI OCT 12 2012
MVFR CIGS EXPECTED TO CONTINUE THIS AFTERNOON AND OVERNIGHT WITH A
BRIEF PERIOD TO VFR POSSIBLE LATER THIS AFTERNOON IF LOWER DECK
SCATTERS OUT. IFR CEILINGS WILL REDEVELOP OVERNIGHT BEFORE DRIER
AIR SWEEPS IN THE FROM THE WEST AROUND 12Z. KEPT VCTS IN FOR KGLD
FROM 20Z-00Z BUT FEEL MOST PRECIPITATION WILL BE -SHRA. FOR NOW
KEPT MENTION OF PRECIPITATION OUT OF KMCK TAF WITH BETTER CHANCES
TO SOUTH.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DLF
LONG TERM...JTL
AVIATION...DLF
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1248 PM MDT FRI OCT 12 2012
.SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY)
ISSUED AT 1245 PM MDT FRI OCT 12 2012
LATEST THINKING IS THERE WILL BE TWO POTENTIAL ROUNDS OF
PRECIPITATION ASSOCIATED WITH THE LARGE UPPER LOW OVER SOUTHERN
NEVADA THAT WILL AFFECT THE REGION IN THE NEXT 18 HOURS. FIRST...A
SHORT WAVE TROUGH CURRENTLY LIFTING NORTHEAST ACROSS THE OKLAHOMA
PANHANDLE WILL INITIATE SHOWERS AND ISOLATED THUNDERSTORMS THIS
AFTERNOON FROM SOUTHWEST TO NORTHEAST BETWEEN ABOUT 20Z AND 01Z.
THE NAM SHOWS DECENT ELEVATED CAPE AROUND 1000 J/KG HOWEVER 0-6 KM
BULK SHEAR IS ONLY ABOUT 25 KTS THIS AFTERNOON. SUB-SEVERE HAIL
AND C-G LIGHTNING ARE THOUGHT TO BE THE MAIN THREATS. THIS FIRST
ROUND OF PRECIP SHOULD BEGIN TO WEAK AND LOSE COVERAGE AS THE
UPPER TROUGH LIFTS FURTHER NORTHEAST AFTER 00Z. ONE MODULATING
INFLUENCE THIS AFTERNOON IS POSITION OF 250 MB JET. THE CURRENT
LOCATION PUTS OUR AREA IN THE RIGHT EXIT REGION WHICH MAY EXPLAIN
THE LOOK OF THE HRRR REFLECTIVITY FIELDS LATER THIS AFTERNOON
WITH PRECIPITATION SPLITTING AND WEAKENING.
THE BULK OF THE SYSTEM IS EXPECTED TO APPROACH THE AREA OVERNIGHT...
BUT THINK BETTER CHANCES OF SHOWERS AND THUNDERSTORMS WILL BE IN
THE SOUTHEAST COUNTIES IN THE 06-12Z TIME FRAME. THE NAM SHOWS
SOME CAPE IN THE -10 TO -20 C HAIL GROWTH REGION AT THAT TIME,
PLUS 0-6 KM SHEAR WILL INCREASE TO AROUND 70 KTS INDICATING A FEW
STORMS OVERNIGHT HAVE THE POTENTIAL TO PRODUCE SEVERE HAIL IF
THINGS COME TOGETHER AS PLANNED. ALSO KEPT MENTION OF AREAS OF FOG
OVERNIGHT WITH LOW LEVEL RH VALUES ABOVE 95 PERCENT.
ON SATURDAY...SOMEWHAT LESS CERTAIN REGARDING POTENTIAL FOR
SCATTERED SHOWERS DURING THE AFTERNOON. LAPSE RATES NOT ALL THAT
STEEP AS UPPER SYSTEM MOVES OVERHEAD...AND SUBSIDENCE BEHIND UPPER
TROUGH WITH RIDGING MOVING IN WILL COINCIDE WITH PEAK HEATING. KEPT
SLIGHT CHANCES FOR SHOWERS GOING FOR NOW BUT CONFIDENCE IS NOT THAT
HIGH FOR DECENT COVERAGE IF LATEST NAM-GFS VERIFY.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 305 AM MDT FRI OCT 12 2012
NORTHWEST FLOW WILL BEGIN TO FLATTEN OUT OVER THE WESTERN HALF OF
THE COUNTRY AS A SHORTWAVE TROUGH CONTINUES TO MOVE EASTWARD THROUGH
THE OHIO RIVER VALLEY. LEE TROUGH WILL DEEPEN AHEAD OF A SHORTWAVE
TROUGH THAT WILL BEGIN TO DIG INTO THE ROCKIES BY LATE TUESDAY. THE
ASSOCIATED COLD FRONT WILL MOVE ACROSS THE AREA TUESDAY AND GIVEN A
STRONG 250 MB JET STREAK NOSING INTO THE NORTHERN CENTRAL
PLAINS...MAY HAVE A FEW SCATTERED SHOWERS ACROSS THE NORTH. GIVEN
THE UNCERTAINTY AND TIMING OF THIS SYSTEM...HAVE KEPT AREA DRY FOR
NOW. NORTHWEST FLOW RETURNS OVER THE AREA AND WILL HELP KEEP
TEMPERATURES MILD AND DRY THROUGH THE REMAINDER OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY MORNING) ISSUED
AT 1245 AM MDT FRI OCT 12 2012
MVFR CIGS EXPECTED TO CONTINUE THIS AFTERNOON AND OVERNIGHT WITH A
BRIEF PERIOD TO VFR POSSIBLE LATER THIS AFTERNOON IF LOWER DECK
SCATTERS OUT. IFR CEILINGS WILL REDEVELOP OVERNIGHT BEFORE DRIER
AIR SWEEPS IN THE FROM THE WEST AROUND 12Z. KEPT VCTS IN FOR KGLD
FROM 20Z-00Z BUT FEEL MOST PRECIPITATION WILL BE -SHRA. FOR NOW
KEPT MENTION OF PRECIPITATION OUT OF KMCK TAF WITH BETTER CHANCES
TO SOUTH.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DLF
LONG TERM...PMM
AVIATION...DLF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
407 PM EDT FRI OCT 12 2012
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 406 PM EDT FRI OCT 12 2012
WV IMAGERY AND RUC ANALYSIS INDICATED MAINLY ZONAL NRN STREAM
MID/UPPER LEVEL FLOW ACROSS THE NRN CONUS INTO THE WRN GREAT LAKES.
A VIGOROUS SRN STREAM LOW WAS LOCATED OVER NW AZ. AT THE SFC...SRLY
WINDS WERE INCREASING FROM THE PLAINS INTO THE UPPER MS VALLEY BTWN
HIGH PRES OVER LOWER MI AND A TROUGH DEVELOPING OVER THE WRN PLAINS.
VIS LOOP SHOWED DIURNAL CLOUDS OVER CNTRL UPPER MI THINNING AND
SHIFTING TO THE EAST AS SW WINDS DEVELOP. ANY LEFTOVER LAKE EFFECT
PCPN OVER ERN LAKE SUPERIOR HAD DISSIPATED
AS THE SFC HIGH SHIFTS TOWARD THE MID ATLANTIC STATES AND THE
SHRTWV/SFC LOW LIFTS OUT OF THE CENTRAL ROCKIES INTO THE PLAINS...A
STRENGTHENING SW FLOW WILL DEVELOP OVER THE WESTERN GREAT LAKES
TONIGHT. WITH STRONG WAA AND MOISTURE ADVECTION DEVELOPING WITH
MODERATE TO STRONG 295K-305K ISENTROPIC LIFT...RAIN WILL QUICKLY
DEVELOP AND SPREAD TO THE NORTHWEST. HOWEVER...WITH CONVECTION
LIKELY TO DEVELOP CLOSER TO THE SFC-850 MB WARM FRONT...MOISTURE
ADVECTION INTO UPPER MI MAY BE REDUCED. SO...THE NAM/ECMWF WHICH
INDICATES A SLIGHTLY LATER ARRIVAL(BTWN 09Z-12Z)OF THE PCPN WITH THE
HEAVIER PCPN MAINLY SOUTH OF UPPER MI WAS PREFERRED. EXPECT THE
STRONGER ISENTROPIC LIFT TO DIMINISH AND SHIFT TO THE EAST
DURING THE AFTERNOON AS THE SFC-850 MB WARM FRONT MOVES INTO NRN
LAKE MI AND NRN LWR MI. LIKELY TO CATEGORICAL POPS ARE STILL
WARRANTED ACROSS MUCH OF THE FCST AREA EVEN FOR PCPN AMOUNTS LESS
THAN 0.10 NORTHWEST...0.10 TO 0.25 INCH CNTRL TO NEAR 0.50 INCH EAST
AND FAR SOUTH.
INCREASING CLOUDS AND WIND WILL LIMIT THE DIURNAL FALL OF TEMP...AND
FCST THERMAL PROFILES INDICATE ANY PCPN SHOULD BE IN THE FORM OF
RAIN EVEN THOUGH TEMPS AT SOME OF THE INTERIOR COLD SPOTS MIGHT FALL
AOB 32 EARLY THIS EVENING BEFORE THE THICKER CLOUDS ARRIVE. EVEN
WITH THE STRONG WAA...PCPN AND CLOUDS WILL LIMIT HIGHS TO THE MID
AND UPPER 40S SATURDAY.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 406 PM EDT FRI OCT 12 2012
MOST ATTENTION IN LONG TERM ON SAT NIGHT THROUGH SUN WITH A SYSTEM
THAT MAY BRING A COUPLE INCHES OF RAIN TO PARTS OF THE REGION. THERE
IS SOME UNCERTAINTY WITH THIS SYSTEM DUE TO MODEL DISAGREEMENT.
DIFFERENCES BETWEEN MODELS INITIALLY ARE DUE TO DIFFERENCES IN UPPER
LEVEL MASS FIELDS AS A 250MB LOW MOVES FROM THE CURRENT POSITION
OVER SRN NV...TO WRN KS AS A SHORTWAVE TROUGH AT THE START OF THE
PERIOD 00Z SUN. AT 00Z SUN...THE 00Z/12 ECMWF IS ABOUT 50-60M DEEPER
AND ALSO MORE NEUTRALLY TILTED WITH 250MB HEIGHT TROUGH THAN THE
POSITIVELY TILTED GFS. THE 12Z/12 NAM IS AN OUTLIER THROUGH THE
PERIOD AS WAS RULES OUT. THE REG-GEM IS MORE OF A MIDDLE GROUND
SOLUTION THROUGH MUCH OF THE EVENT.. THE DIFFERENCES BETWEEN MODELS
CONTINUES AT 12Z SUN...WHEN THE GFS BECOMES NEUTRALLY TILED OVER THE
WRN MO BORDER WHILE THE ECMWF IS STRONGER...FASTER AND NEGATIVELY
TILTED WITH THE UPPER TROUGH OVER IA/NRN MO. EVENTUAL SFC LOW TRACK
DIFFERENCES ARE NOT DIFFERENT...ALTHOUGH THERE ARE STILL DIFFERENCES
IN SFC LOW STRENGTH...BUT SOME OF THE LARGER DIFFERENCES WITH PRECIP
AMOUNTS/PLACEMENT COME AROUND 850MB. WHILE THE STRONGER ECMWF
DEEPENS THE SYSTEM AND BRINGS A STRENGTHENING 850MB LOW FROM NE IA
12Z SUN TO NEAR THE STRAITS OF MACKINAW AROUND 00Z MON...THE GFS
BRINGS THE 850MB LOW FROM NRN LAKE SUPERIOR AT 00Z SUN TO NEAR THE
STRAITS AT 18Z SUN...THEN DEEPENS IT RAPIDLY OVER LAKE HURON BY 00Z
MON AS THE UPPER TROUGH BECOMES NEGATIVELY TILTED AND UPPER JETS
PHASE. WILL BE INTERESTED TO SEE WHAT THE 12Z/12 ECMWF COMES IN
WITH...BECAUSE THE GFS AND GEM HAVE BEEN TRENDING WEAKER /TOWARD
WHAT THEY HAVE NOW/ OVER THE LAST FEW RUNS. THE MAIN IMPACT FROM THE
WEAKER SCENARIO IS THAT THE STRONG DEFORMATION/FGEN ON THE LEFT SIDE
OF THE 850MB LOW TRACK ARE DISPLACES SE OF THE CWA...WHILE THE ECMWF
SOLUTION BRINGS A COUPLE OF INCHES OF RAIN SAT NIGHT INTO SUN.
OVERALL THINK THE BEST CHANCES OF PRECIP WILL BE OVER THE SERN CWA
CLOSER TO LAKE MICHIGAN...BOTH SAT NIGHT WITH THE WARM FRONT THAT
WILL BE JUST S OF THE CWA AND AS THE LOW PASSES SUN. WILL SHIFT POPS
SE FROM WHAT IS CURRENTLY IN THE FORECAST.
LINGERED SOME SLIGHT CHANCE POPS OVER NORTH CENTRAL AND E UPPER MI
INTO EARLY MON AS N WINDS OFF LAKE SUPERIOR MAY BRING IN SOME LAKE
EFFECT/UPSLOPE PRECIP WHILE 850MB TEMPS DECREASE TO AROUND -3C. ANY
PRECIP WILL BE LIGHT...AND SOME SOME LIGHT SNOW MAY MIX IN OVER THE
HIGHER TERRAIN LATE SUN NIGHT/EARLY MON MORNING. AS SFC RIDGE SLIDES
ACROSS THE CWA MON AFTERNOON/EVENING AHEAD OF AN UPPER RIDGE THAT
WILL MOVE OVERHEAD TUE NIGHT INTO EARLY TUE.
AFTER MON THERE IS CONSIDERABLE MODEL DISAGREEMENT...LIMITED
CONFIDENCE IN THE FORECAST...ESPECIALLY POPS. HOWEVER...IT DOES
APPEAR MORE CERTAIN THAT TUE AND WED WILL BE WARMER WITH HIGHS
GENERALLY IN THE 50S. USED CONSENSUS OF MODELS FOR MON NIGHT THROUGH
FRI.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 135 PM EDT FRI OCT 12 2012
AS A DRY HIGH PRES RIDGE MOVES ACROSS THE UPPER GREAT LAKES...EXPECT
VFR CONDITIONS TO PREDOMINATE INTO TONIGHT. A STRENGTHENING SSW FLOW
TONIGHT BTWN THE DEPARTING HI AND LOW PRES TAKING SHAPE IN THE PLAINS
WILL RESULT IN SOME MARGINAL LLWS AS WELL AS INCREASING CLOUDS.
ENOUGH MOISTURE MAY ARRIVE LATE IN THE FCST PERIOD TO CAUSE MVFR CIGS
CLOSER TO THE WI BORDER AT IWD. STRONGER MOISTURE INFLOW AHEAD OF
WARM FRONT OVER WI WILL BRING LOWER CIGS INTO THE MVFR RANGE. SRLY
LOW LEVEL FLOW FAVORS EVEN LOWER CIGS INTO THE IFR RANGE AT SAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 406 PM EDT FRI OCT 12 2012
A STEADY SSW WIND UP TO 25 KTS WILL PREVAIL TONIGHT BETWEEN THE
DEPARTING HI AND DEVELOPING LO PRES IN THE PLAINS. AS THE LO PRES
CENTER MOVES TO THE E JUST S OF UPPER MI EARLY SUN...LOOK FOR THE
WINDS TO BACK TO THE N AND INCREASE UP TO 25 TO 30 KTS...ESPECIALLY
OVER THE E HALF. MAY SEE A FEW GALE FORCE GUSTS OVER PORTIONS OF
EASTERN LAKE SUPERIOR SUN. THE APPROACH OF HIGH PRES ON MON WILL CAUSE
A STEADY DECREASE IN WIND SPEED LATER SUN INTO MON. SOUTH WINDS WILL
INCREASE TO 25 KTS OVER MAINLY THE ERN HALF OF THE LAKE ON TUESDAY
AHEAD OF A LOW PRESSURE SYSTEM DEVELOPING OVER THE NRN PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
139 PM EDT FRI OCT 12 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 606 AM EDT FRI OCT 12 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW CONFLUENT NW FLOW
ALF OVER THE UPR GRT LKS BTWN TROFFING OVER ERN CANADA AND A RDG
OVER WRN CANADA. AT THE SFC...HI PRES IS CENTERED OVER WRN MN...WITH
CHILLY /H85 TEMPS -7C TO -8C/ NW FLOW DOMINATING THE CWA. DESPITE
RATHER MOIST LOOK TO 00Z INL/YPL RAOBS AND SUFFICIENT INSTABILITY
FOR LK EFFECT PCPN /LK SUP WATER TEMPS 8C OVER THE W TO 10C OVER THE
E/...THE BULK OF THE LK EFFECT SHRASN AND FOR THAT MATTER THE LO
CLDS ARE CONFINED TO AN AREA OVER THE ECNTRL PART OF THE LK...WHERE
THE SFC OBS INDICATE SOME LLVL CNVGC BTWN THE LARGER SCALE NW FLOW
AND A MORE NNE LAND BREEZE FLOW OFF SE ONTARIO ENHANCE BY DIURNAL
COOLING THERE. SEEMS LIKE INTENSE SUBIDENCE/DRYING ALF IN THE WAKE
OF SHRTWV THAT PASSED YDAY AS WELL AS LARGER SCALE ACYC FLOW
ASSOCIATED WITH MN HI PRES IS SUPPRESSING THE PCPN/CLD COVER.
HOWEVER...MQT RADAR DOES INDICATE SOME REFLECTIVIES OVER 30DBZ
WITHIN THE MORE INTENSE SHRASN STREAMING INTO ALGER/NRN SCHOOLCRAFT
COUNTIES.
MAIN FCST CONCERNS IN THE SHORT TERM ARE LK EFFECT SHRASN TRENDS
THIS MRNG. FOCUS FOR LATER TNGT SHIFTS TO CHC OF PCPN AS DVLPG SW
WIND ON THE WRN FLANK OF RETREATING HI PRES IS PROGGED TO ADVECT
MUCH MOISTER AIR NEWD INTO THE UPR LKS.
TODAY...WITH RISING H5 HGTS THRU THE DAY...SFC HI PRES CENTER IS
PROGGED TO MOVE STEADILY ESEWD TO OVER LAKE ERIE BY 00Z SAT. AS THE
LLVL FLOW BACKS TO THE SW THIS AFTN AND ADVECTS MUCH DRIER AIR SHOWN
ON THE 00Z MPX RAOB INTO THE UPR LKS...EXPECT LK EFFECT SHRASN OVER
THE E TO BECOME INCRSGLY CONFINED TO NEAR THE SHORE E OF GRAND
MARAIS AND THEN END COMPLETELY IN THE AFTN IN THE PRESENCE OF
DAYTIME HEATING. TO THE W...ANY LINGERING LK CLDS SHOULD GIVE WAY TO
MOSUNNY CONDITIONS/SCT CU WITH THE ARRIVAL OF THE DRIER AIR FM THE
SW. DIURNAL SC MIGHT BE MORE RESILIENT OVER THE E WITH LINGERING H85
THERMAL TROF/H85 TEMPS ARND -5C THRU 00Z. PER MIXING TO H85-8 ON NAM
FCST SDNGS AND HI TEMPS OBSVD UPSTREAM YDAY...EXPECT MAX TEMPS IN
THE 40S.
TNGT...AS THE SFC HI SHIFTS TOWARD THE MID ATLANTIC STATES AND A
SHRTWV/SFC LO SHIFT OUT OF THE CENTRAL ROCKIES INTO THE PLAINS...A
STRENGTHENING SW FLOW IS FCST TO DVLP OVER THE UPR LKS. MOST RECENT
MODEL RUNS HAVE BEEN CONSISTENT IN GENERATING SOME LGT PCPN OVER
MUCH OF THE W HALF OF THE CWA IN THIS WAD REGIME FEATURING
IMPRESSIVE ISENTROPIC ASCENT ON THE 295-305K SFCS THAT ADVECTS PWAT
UP TO 1 INCH /175-200 PCT OF NORMAL/ NEAR THE WI BORDER BY 12Z SAT.
ALTHOUGH THE BETTER HGT FALLS/DPVA/UPR DVGC LAG TO THE W CLOSER TO
THE SHRTWV IN THE PLAINS SO THAT THE LYR ABV H65-6 REMAINS
RELATIVELY DRY /INCLUDING THE DGZ/...THIS IMPRESSIVE WAD/MOISTENING
JUSTIFIES AT LEAST LO CHC POPS OVER THE W HALF NEAR THE WI BORDER.
INCRSG CLDS/WINDS WL LIMIT THE DIURNAL FALL OF TEMP...AND FCST
THERMAL PROFILES INDICATE ANY PCPN SHOULD BE IN THE FORM OF RA EVEN
THOUGH TEMPS AT SOME OF THE INTERIOR COLD SPOTS MIGHT FALL AOB 32
EARLY IN THE EVNG BEFORE THE THICKER CLDS ARRIVE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 606 AM EDT FRI OCT 12 2012
AS THE MID LEVEL TROUGH AND ASSOC SFC LOW MOVE OUT OVER THE CENTRAL
PLAINS ON SAT...STRONG WAA/ISENTROPIC ASCENT WILL CONTINUE OVER THE
FCST AREA...ESPECIALLY THRU MID DAY SAT. LIKELY TO CATEGORICAL POPS
ARE STILL WARRANTED ACROSS MUCH OF THE FCST AREA. SINCE MODELS ARE
INDICATING THE STRONGEST PUSH OF 295-300K ASCENT OVER SCNTRL AND ERN
UPPER MI...WILL MAINTAIN HIGHEST CATEGORICAL POPS 80-90 PCT OVER
THESE AREAS WHILE TAPERING POPS TO CHC 40-50 OVER NW AWAY FM BEST
WAA/ISNETROPIC ASCENT.
SAT NIGHT/SUN...MODELS SHOW SHORTWAVE TROUGH OVER THE PLAINS LIFTING
NE...CROSSING LWR MI SUN WITH ASSOCIATED SFC LOW TRACKING THRU NRN
LWR MI. THE GFS IS A BIT FASTER THAN THE ECMWF/CANADIAN SOLN BUT ALL
THESE MODELS HAVE THE SFC LOW TRACKING ACROSS NRN LOWER MI FM EITHER
EARLY SUN AFTERNOON (GFS) TO LATE SUN AFTERNOON (ECMWF/CANADIAN).
BASED ON THIS SFC LOW TRACK WHICH IS JUST SOUTH OF THE PROGGED TRACK
OF THE 850 MB...WOULD EXPECT DEFORMATION ZONE/HEAVIEST RAINFALL TO
CROSS THE S CENTRAL AND ERN PORTIONS OF THE FCST AREA. THESE AREAS
OF THE CWA ALSO LINE UP WITH MODEL INDICATED DEEP LAYER Q-VECT CONV
AND ARE CO-LOCATED WITH COUPLED UPPER JET STRUCTURE AND ALONG AND
SOUTH OF ASSOC 850 MB FGEN FORCING. AGAIN HAVE TAPERING POPS FROM
90-100 PCT SCNTRL AND EAST TO CHC POPS (30-40 PCT) FAR WEST FOR SAT
NIGHT AND SUNDAY. LOOKING AT MODEL AVG QPF...WOULD EXPECT TO SEE
RAINFALL AMOUNTS WELL OVER AN INCH OVER SCNTRL AND ERN PORTIONS OF
THE CWA WITH SOME LOCATIONS PERHAPS APPROACHING TWO INCHES. AS
SYSTEM CONTINUES TO LIFT NE...DRYING TREND WILL GET UNDERWAY FROM W
TO E LATE IN THE DAY SUN. THE DRYING TREND WILL CONTINUE SUNDAY
NIGHT AS HIGH PRES BUILDS IN FM THE WEST.
WITH SFC HIGH PRES RIDGE PASSING OVER THE AREA MON...EXPECT A DRY
DAY AFTER PERHAPS TO FEW LINGERING SHOWERS EARLY MORNING EAST.
STILL PLENTY OF MODEL UNCERTAINTY FOR NEXT WEEK. MORE ZONAL FLOW FOR
EARLY NEXT WEEK WITH WAA AND POTENTIAL FOR WEAK SHORTWAVES MOVING
THROUGH REGION COULD SUPPORT SOME LIGHT RAIN CHCS LATE MON NIGHT
INTO TUESDAY. MODELS THEN DIFFER ON HOW MUCH MID LVL TROF WILL
AMPLIFY OVER THE PLAINS FOR MID TO LATE NEXT WEEK. UNTIL MODELS COME
INTO BETTER AGREEMENT ON TROF EVOLUTION WILL MAINTAIN GOING CHC POPS
FOR MID TO LATE NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 135 PM EDT FRI OCT 12 2012
AS A DRY HIGH PRES RIDGE MOVES ACROSS THE UPPER GREAT LAKES...EXPECT
VFR CONDITIONS TO PREDOMINATE INTO TONIGHT. A STRENGTHENING SSW FLOW
TONIGHT BTWN THE DEPARTING HI AND LOW PRES TAKING SHAPE IN THE PLAINS
WILL RESULT IN SOME MARGINAL LLWS AS WELL AS INCREASING CLOUDS.
ENOUGH MOISTURE MAY ARRIVE LATE IN THE FCST PERIOD TO CAUSE MVFR CIGS
CLOSER TO THE WI BORDER AT IWD. STRONGER MOISTURE INFLOW AHEAD OF
WARM FRONT OVER WI WILL BRING LOWER CIGS INTO THE MVFR RANGE. SRLY
LOW LEVEL FLOW FAVORS EVEN LOWER CIGS INTO THE IFR RANGE AT SAW. &&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 606 AM EDT FRI OCT 12 2012
EXPECT NW WINDS UP TO 25 KTS OVER THE HALF OF THE LAKE THIS MORNING
TO BACK STEADILY TO THE SW TODAY AS THE HI PRES CENTER OVER MN MOVES
STEADILY TO LAKE ERIE BY THIS EVENING. A STEADY SSW WIND UP TO 25
KTS WILL PREVAIL TONIGHT BETWEEN THE DEPARTING HI AND DEVELOPING LO
PRES IN THE PLAINS. AS THE LO PRES CENTER MOVES TO THE E JUST S OF
UPPER MI EARLY SUN...LOOK FOR THE WINDS TO BACK TO THE N AND
INCREASE UP TO 25 TO 30 KTS...ESPECIALLY OVER THE E HALF. MAY SEE A
FEW GALE FORCE GUSTS OVER PORTIONS OF EASTERN LAKE SUPERIOR SUN. THE
APPROACH OF HI PRES ON MON WILL CAUSE A STEADY DECREASE IN WIND
SPEED LATER SUN INTO MON. SOUTH WINDS WILL INCREASE TO 25 KTS OVER
MAINLY THE ERN HALF OF THE LAKE ON TUESDAY AHEAD OF A LOW PRESSURE
SYSTEM DEVELOPING OVER THE NRN PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...VOSS
AVIATION...JLB
MARINE...KC/VOSS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1230 PM CDT FRI OCT 12 2012
.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
258 AM CDT FRI OCT 12 2012
MAIN FORECAST CONCERN IS ON SEVERE WEATHER POTENTIAL SATURDAY INTO
SATURDAY NIGHT.
CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A SPLIT FLOW PATTERN ACROSS NORTH AMERICA. IN THE NORTHERN
STREAM...WEAK RIDGING WAS NOTED OVER THE NORTHERN U.S. ROCKIES AND
THEN DOWNSTREAM TROUGHING OVER THE GREAT LAKES. IN THE SOUTHERN
STREAM...AN UPPER LOW WAS OVER SOUTHERN CALIFORNIA WITH RIDGING
BUILDING UP AHEAD OF IT ACROSS THE CENTRAL AND SOUTHERN PLAINS. OVER
THE FORECAST AREA...SATELLITE IMAGERY SHOWED SKIES HAVE CLEARED OUT
THANKS TO SUBSIDENCE AND DRYING IN THE WAKE OF THE GREAT LAKES
TROUGHING. ALSO REFLECTED OF THE SUBSIDENCE IS A 1030MB SURFACE HIGH
CENTERED NEAR MINNEAPOLIS. PRECIPITABLE WATER VALUES WERE QUITE DRY
ON THE 00Z MPX SOUNDING...0.17 INCHES OR 30 PERCENT NORMAL. SURFACE
DEWPOINTS ALSO REFLECTIVE OF THE DRYING...DOWN IN THE TEENS TO LOWER
20S. DECENT AMOUNT OF COLD AIR ACCOMPANYING THE SURFACE HIGH WITH
850MB TEMPS THAT DROPPED TO -4C AT MPX AT 00Z COMPARED TO +3C 12
HOURS EARLIER. TO THE SOUTH...A STATIONARY FRONTAL BOUNDARY WAS
POSITIONED FROM OKLAHOMA INTO THE OHIO RIVER VALLEY. SOUTH OF THIS
FRONT...PLENTIFUL MOISTURE WAS NOTED WITH SURFACE DEWPOINTS IN THE
MID 60S TO LOWER 70S ACROSS OKLAHOMA AND MUCH OF TEXAS. 00Z FORT
WORTH SOUNDING HAD A PRECIPITABLE WATER VALUE OF 1.6 INCHES OR 176
PERCENT OF NORMAL. 850MB PROFILER AND VWP DATA CURRENTLY SHOWS MUCH
OF THIS MOISTURE BEING ADVECTED INTO AND ALONG THE STATIONARY
FRONTAL BOUNDARY.
TODAY AND TONIGHT...MAJOR CHANGES LOOK TO OCCUR IN THE WEATHER
PATTERN ACROSS THE FORECAST AREA DURING THIS TIME. THE UPPER LOW IN
CALIFORNIA MODELS ARE ALL IN GOOD AGREEMENT LIFTING IT OUT INTO
NORTHEAST COLORADO BY 12Z SATURDAY. IN RESPONSE TO THIS EJECTION THE
SUBTROPICAL RIDGING BUILDING OVER THE CENTRAL AND SOUTHERN PLAINS
GETS PULLED NORTHWARD INTO THE FORECAST AREA. AS A RESULT...THIS
HIGH PRESSURE BUILDING INTO THE FORECAST AREA RIGHT NOW AT THE
SURFACE WILL NOT HANG AROUND LONG. IN FACT...BY 00Z...15-20
SOUTHERLY 925MB WINDS ARE PROGGED AS THE HIGH SHIFTS OVER LAKE ERIE.
WE SHOULD SEE PLENTY OF SUN TODAY BEING UNDER THE INFLUENCE OF DRY
AIR NOTED ON THE 00Z MPX SOUNDING. 850MB TEMPS AT 18Z AROUND 1C IN
NORTHEAST IOWA TO -4C IN TAYLOR COUNTY SUGGESTS HIGHS FROM THE UPPER
40S TO MID 50S...COOLEST AS EXPECTED IN TAYLOR COUNTY. THINGS GET A
LITTLE MORE INTERESTING TONIGHT AS 850MB MOISTURE TRANSPORT KICKS
INTO HIGH GEAR AHEAD OF THE EJECTING UPPER LOW. 850MB WINDS
THEMSELVES ARE PROGGED TO INCREASE TO 35 TO 50 KT FROM THE SOUTHERN
PLAINS INTO THE FORECAST AREA BY 06Z...HELPING TO BRING UP THE
MOISTURE CURRENTLY SEEN ACROSS OKLAHOMA AND TEXAS. THIS RAPID
INCREASE IN MOISTURE WILL LEAD TO PRECIPITATION DEVELOPMENT...
PERHAPS AS EARLY AS 03Z AS SUGGESTED BY THE 12.00Z NAM. MORE LIKELY
IS TO HAVE WIDESPREAD SHOWERS ACROSS THE FORECAST AREA AFTER 06Z.
THUNDERSTORMS ARE ALSO EXPECTED WITH THIS ACTIVITY WITH MODELS
SHOWING UPWARDS OF 600 J/KG OF MUCAPE...MOSTLY ROOTED AT OR ABOVE
850MB PER CROSS-SECTIONS...ACCOMPANYING THE MOISTURE TRANSPORT. IN
ADDITION TO THE MOISTURE ADVECTION...850MB TEMPS ARE GOING TO SHOOT
UP...REACHING AROUND 12C BY 12Z. AS SUCH...ANTICIPATING LOWS IN THE
EVENING WITH TEMPERATURES RISING THEREAFTER.
SATURDAY AND SATURDAY NIGHT...THIS PERIOD HAS BEEN INTERESTING TO
WATCH OVER THE PAST SEVERAL DAYS WITH RESPECT TO WHAT HAPPENS WITH
THE UPPER LOW. ALL MODELS EXCLUDING THE NAM HAVE HAD ISSUES WITH THE
TRACK AND SPEED. HOWEVER...THERE IS A STRONG CONSENSUS NOW THAT THIS
UPPER LOW IS GOING TO TRACK EAST INTO SOUTHERN IOWA BY 12Z SUNDAY
AND TAKE ON A NEGATIVE TILT. MUCH OF THIS IS CAUSED BY A POTENT
SHORTWAVE HANGING BACK FROM THE UPPER LOW CROSSING THE SOUTHERN
PLAINS. THIS HAS BIG IMPLICATIONS FOR THE FORECAST AREA AS IT
DICTATES THE TRACK OF THE BEST PV ADVECTION...WHICH NOW STAYS MOSTLY
SOUTH OF THE AREA UNTIL MAYBE 12Z SUNDAY SOUTH OF I-90. STILL...
THERE IS PLENTY OF FORCING FOR PRECIPITATION. ON SATURDAY...THE
FORCING REMAINS THAT PERSISTENT STRONG 850MB MOISTURE TRANSPORT ZONE
WITH THE NOSE INTO THE FORECAST AREA. NOTE THAT THE ZONE DOES SLOWLY
SHIFT EAST IN RESPONSE TO THE APPROACHING UPPER LOW. AS SUCH...
PRECIPITATION MAY DIMINISH IN THE AFTERNOON ACROSS MINNESOTA.
PERSISTENT ADVECTION OF INSTABILITY WITHIN THE MOISTURE TRANSPORT...
WHICH SHOULD INCREASE THROUGH THE DAY AS THE AIRMASS SOUTH OF THE
AREA HEATS UP...SUGGESTS QUITE A BIT OF THUNDERSTORM ACTIVITY. BY
21Z AND CONTINUING THROUGH THE EVENING...500-1000 J/KG OF MUCAPE IS
PROGGED OVER THE FORECAST AREA...HIGHEST SOUTH OF I-90.
PRECIPITATION OVERALL LOOKS PRETTY GOOD FOR MOST OF THE AREA
SATURDAY NIGHT TOO...DUE TO A COMBINATION OF INCREASING LOW TO MID
LEVEL FRONTOGENESIS AND RIGHT ENTRANCE REGION SUPPORT FROM AN UPPER
JET DEVELOPING OVER UPPER MICHIGAN. NORTHWEST SECTIONS OF THE AREA
COULD BE ON THE EDGE OF THE PRECIPITATION... THOUGH...AS INDICATED
BY THE 12.00Z NAM AND AS SUCH SLIGHT LOWER CHANCES ARE PRESENT
THERE. GENERALLY FOLLOWED A BLEND OF GUIDANCE FOR HIGHS AND LOWS.
ONE SIDE NOTE WHICH REFLECTS THE CHANGE IN AIRMASSES...MOST
LOCATIONS WILL SEE A DEWPOINT JUMP OF 30 TO 40 DEGREES IN 24 HOURS
BETWEEN 21Z TODAY AND 21Z SATURDAY.
SEVERE WEATHER POTENTIAL FOR SATURDAY INTO SATURDAY NIGHT...ALTHOUGH
THE 500-1000 J/KG OF CAPE IN THE AFTERNOON AND EVENING IS THIN...
EXTENDING UP TO AN EQUILIBRIUM LEVEL AROUND 250MB...THE
ENVIRONMENT FOR THE MOST PART IS UNCAPPED IN THE WARM SECTOR AHEAD
OF A SURFACE LOW COMING ACROSS NORTHERN IOWA. WARM SECTOR LOOKS TO
BE SITUATED MOSTLY SOUTH OF I-90. COMBINE THIS CAPE WITH A HIGHLY
SHEARED ENVIRONMENT NOTED BY 0-6KM SHEAR OF 40-50KT AND 0-1KM
SHEAR AROUND 25 KT YIELDS CONCERN OF DISCRETE TORNADIC SUPERCELLS
IN THE WARM SECTOR. HODOGRAPHS SUGGEST STRONGLY DOMINANT RIGHT
MOVING SUPERCELLS. DAMAGING WINDS WOULD BE A CONCERN TOO GIVEN THE
SHEAR. THIN CAPE PLUS RELATIVELY HIGH FREEZING LEVELS FOR THIS
TIME OF YEAR (AROUND 11000 FT) SHOULD PRECLUDE MUCH OF A LARGE
HAIL HAZARD. OVERALL...HIGHER SEVERE THREAT SHOULD EXIST SOUTH OF
THE FORECAST AREA WHERE CAPE AND DYNAMIC FORCING IS GREATER.
SWODY2 SEVERE WEATHER PROBABILITIES DEPICT THIS WELL. IT SHOULD BE
STRESSED THAT ANY UNEXPECTED SUNSHINE ON SATURDAY COULD
DRAMATICALLY INCREASE THE SEVERE WEATHER POTENTIAL. PRESENT
FORECASTS PORTRAY A MORE LIKELY CLOUDY SCENARIO.
SUNDAY AND SUNDAY NIGHT...MODELS ARE PRETTY QUICK IN EJECTING THE
NEGATIVE TILT SHORTWAVE AND THE ASSOCIATED SURFACE SYSTEM AWAY FROM
THE AREA. BY 00Z MONDAY...BOTH FEATURES SHOULD BE NEAR LAKE HURON.
THEREFORE...AFTER SOME DEFORMATION PRECIPITATION ON THE BACK SIDE OF
THE SYSTEM AFFECTS THE AREA IN THE MORNING...ESPECIALLY ACROSS
WISCONSIN...ANTICIPATING CONDITIONS TO DRY OUT FOR THE AFTERNOON.
UPPER TROUGHING DOES LINGER OVER THE AREA THROUGH SUNDAY NIGHT...
AIDED BY A FEW PACIFIC SHORTWAVES DROPPING IN BEHIND THE NEGATIVELY
TILTED SHORTWAVE. HOWEVER...AT MOST IT LOOKS LIKE THESE WOULD BRING
CLOUDS. DESPITE BEING IN COLD ADVECTION IN THE WAKE OF SUNDAYS
SYSTEM...850MB TEMPS ONLY FALL TO 2-4C. COMBINE THIS WITH SOME
AFTERNOON SUN SHOULD BOOST HIGHS INTO THE MID 50S TO LOW
60S...WARMEST WEST OF THE MISSISSIPPI RIVER WHERE THE MOST SUN IS
EXPECTED. COULD BE A COOL NIGHT SUNDAY NIGHT WITH A SURFACE RIDGE
BUILDING IN...BUT IT WILL ALL DEPEND ON THE CLOUDS. HAVE LEANED
TOWARDS A BLEND OF GUIDANCE WITH A KNOCK DOWN IN TEMPS FOR THE
TYPICAL COOLER SPOTS. MAY HAVE TO KEEP AN EYE ON VALLEY FOG
POTENTIAL IF THE SURFACE RIDGE BUILDS IN A LITTLE FASTER AND SKIES
STAY MOSTLY CLEAR.
.LONG TERM...MONDAY THROUGH THURSDAY NIGHT
258 AM CDT FRI OCT 12 2012
12.00Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES PORTRAY YET ANOTHER
PATTERN CHANGE DURING THE LONG TERM PERIOD...FORECASTING TROUGHING
ACROSS THE NORTHERN PLAINS INTO THE WESTERN GREAT LAKES BY THURSDAY.
THIS IS SIMILAR TO WHAT WE HAVE JUST EXPERIENCED FOR THE PAST
WEEK...THOUGH THE AIR IN THE TROUGH IS NOT NEARLY AS COOL.
THE PERIOD BEGINS WITH A FAST WEST-NORTHWEST FLOW FROM THE PACIFIC
NORTHWEST INTO THE NORTHERN PLAINS. THERE ARE INDICATIONS OF A
SHORTWAVE RIDING THROUGH THIS FLOW AND AMPLIFYING A TROUGH OVER THE
NORTHERN PLAINS ON TUESDAY...CAUSING RIDGING TO DEVELOP OVER THE
FORECAST AREA. THUS...IT WOULD APPEAR MONDAY AND IN PARTICULAR
TUESDAY SHOULD BE THE WARM DAYS OF THE WEEK. 850MB TEMPS CLIMB TO
6-9C BY 00Z TUESDAY AND 8-11C BY 00Z WEDNESDAY. MAY NOT BE ABLE TO
REALIZE THE FULL WARMTH ON TUESDAY...THOUGH...AS WARM ADVECTION AND
DPVA FORCED CLOUDS AND PRECIPITATION SPREAD INTO THE AREA AHEAD OF
THE NORTHERN PLAINS TROUGH. THE NORTHERN PLAINS TROUGH IS THEN
SUGGESTED TO SHIFT EAST OVER THE AREA FOR WEDNESDAY INTO THURSDAY.
KEPT PRECIPITATION CHANCES GOING FOR WEDNESDAY INTO WEDNESDAY NIGHT
PER CONSENSUS...DUE TO A DECENT STRENGTH SHORTWAVE SUGGESTED TO DROP
INTO THE TROUGH. AS THE SHORTWAVE PUSHES OFF TO THE EAST FOR
THURSDAY...FOLLOWED A DRY FORECAST. AGAIN...TEMPERATURES WILL COOL
DOWN WEDNESDAY INTO THURSDAY AS 850MB TEMPS DROP TO 4-6C AND 2-4C
RESPECTIVELY. AFTER MONDAY THROUGH WEDNESDAY PROGGED TO MAINLY BE IN
THE 60S...THURSDAY LOOKS TO END UP THE 50S.
&&
.AVIATION...THROUGH 18Z SATURDAY
1230 PM CDT FRI OCT 12 2012
BIGGEST FORECAST CONCERN IS ON CONVECTION LATE TONIGHT INTO
SATURDAY AND CEILINGS HEIGHTS. HIGH PRESSURE DRIFTS EAST OF THE
AREA THIS AFTERNOON...WITH RATHER IMPRESSIVE MOISTURE RETURN THIS
EVENING. LOW LEVEL JET STRENGTHENS WITH MOISTURE TRANSPORT NOSING
INTO THE REGION AFTER 03Z THIS EVENING. EXPECT SHOWERS TO DEVELOP
OVER THE AREA BETWEEN 03Z-06Z AND THEN CONTINUE TO ERUPT THROUGH
THE OVERNIGHT HOURS. INSTABILITY DOES INCREASE THROUGH THE NIGHT
AND DID INCLUDE VCTS AT BOTH SITES. EXPECT CEILINGS TO DECREASE
AFTER 06Z INTO THE MVFR CATEGORY AND CANNOT RULE OUT SOME IFR
CEILINGS AFTER 10Z AND THEN CONTINUING THROUGH 18Z. WITH THE
INCREASING LOW LEVEL JET TONIGHT DID ADD MENTION OF LLWS AT KLSE
AS 2000 FOOT WINDS INCREASE TO 48 TO 50 KNOTS WHILE SURFACE WINDS
EXPECTED AROUND 10 TO 12 KNOTS.
&&
.HYDROLOGY...TONIGHT THROUGH SUNDAY
258 AM CDT FRI OCT 12 2012
QPF WISE FOR THE TONIGHT THROUGH SUNDAY MORNING SYSTEM...REALLY HARD
TO SAY. THE MAXIMUM AREA SHOULD BE OVER THE SOUTHEASTERN 1/3 OF THE
FORECAST AREA...WHERE THE LONGEST PERIOD OF 850MB MOISTURE TRANSPORT
NOSES IN AND THEN GETS HIT BY THE DEFORMATION ON THE BACK SIDE OF
THE SYSTEM. PRECIPITABLE WATER VALUES CLIMB TO AROUND 1.5 INCHES OR
200-250 PERCENT OF NORMAL TONIGHT AND HOVER AROUND THERE INTO SUNDAY
MORNING. POTENTIAL IS DEFINITELY THERE TO GET 1 TO 2 INCHES FOR THE
ENTIRE TIME PERIOD...AS SUGGESTED BY HPC FORECASTS AND SREF
PROBABILITIES...WITH LOCALLY HIGHER AMOUNTS DUE TO THE CONVECTIVE
NATURE. IN FACT...THE LATEST 12.00Z ECMWF HAS UPWARDS OF 3-3.5
INCHES. THE LANDSCAPE AND RIVERS REALLY COULD USE THIS RAIN GIVEN
THE SEVERE TO EXTREME DROUGHT CONDITIONS IN PLACE. THEREFORE...NO
FLOODING IS ANTICIPATED.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
258 AM CDT FRI OCT 12 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...JLR
HYDROLOGY...AJ