Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 10/26/12
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1000 PM MDT THU OCT 25 2012
.UPDATE...
SHORT TERM...SNOW CONTINUES TO FALL OVER AND ALONG THE FRONT
RANGE. HAVE WITNESSED AN MODEST INCREASE IN SNOWFALL COVERAGE
AND INTENSITY GENERALLY NORTH OF THE DENVER METRO AREA IN THE
PAST HOUR WITH BIT OF ENHANCEMENT IN THE SOUTHEASTERLY FLOW ON THE
PLAINS AND WITH INCREASING QG ASCENT AS PER THE RUC AND NAM.
MODELS SNOW FIELDS INDICATE A BULLS EYE OF 3-7 INCH SNOW
ACCUMULATION BY 09Z OVER NORTHERN PORTIONS OF THE FRONT RANGE
FOOTHILLS...INCLUDING THE FOOTHILLS OF LARIMER AND BOULDER
COUNTIES. THIS MAY BE A BIT OVERDONE BECAUSE WE HAVEN/T SEEN
ANYTHING LIKE THAT THUS FAR THIS EVENING. MEANWHILE SOUTHERN
PORTIONS OF THE I-25 CORRIDOR INCLUDING THE DENVER METRO AREA MAY
HAVE SEEN MOST OF THE SNOW ACCUMULATION THEY/RE GOING TO SEE
TONIGHT AS SOUTHEAST LOW LEVEL FLOW NOT ALL THAT FAVORABLE FOR
SNOW PRODUCTION IN THESE AREAS. PROBABLY ANOTHER 1-2 INCHES BY 1
AM. FARTHER OUT ON THE PLAINS...PARTICULARLY IN THE ELBERT AND
LINCOLN COUNTY AREA...SNOWFALL LOOKS CONVECTIVE ON RADAR WITH THE
OCCASIONAL LIGHTNING STRIKE. SNOW AMOUNTS IN THIS AREA GENERALLY
NO MORE THAN AN INCH OR TWO...BUT CANNOT RULE OUT A QUICK 2-3
INCH SNOWFALL WITH THE ISOLATED CONVECTION. HAVE ADJUSTED THE
CURRENT FORECAST GRIDS TO ACCOUNT FOR ALL THIS. STILL LOOKS AS
THOUGH CLEARING SHOULD COMMENCE DURING THE MORNING HOURS AS DRIER
AIR SPREADS IN FROM THE NORTHWEST. YET IN MAY TAKE MOST OF THE DAY
FOR SKIES TO CLEAR ON THE FAR EASTERN PLAINS AND WEST FACING
MOUNTAINS WHERE WE MAY SEE ISOLATED SNOW SHOWERS LINGERING THROUGH
THE AFTERNOON.
&&
.AVIATION...THUS FAR THIS EVENING SNOW HAS BEEN NORTH OF DIA AND
SOUTH OF DIA. ONE REASON FOR THIS IS SOUTHEAST FLOW IS NOT A GOOD
UPSLOPE DIRECTION FOR DIA. THE UPPER TROUGH IN WESTERN COLORADO
WILL CONTINUE MOVING EAST AND PROVIDE LIFT TO THE FRONT RANGE...
AND SO WE SHOULD SEE RADAR ECHOES FILLING IN HOUR OR SO IN THE
DENVER AREA. EXPECT LIGHT SNOW TO CONTINUE...AND OCCASIONAL SNOW
SHOWERS TO PERSIST PAST MIDNIGHT. AREA AIRPORTS CAN EXPECT MVFR
CEILINGS AND VISIBILITIES...WITH SHORT LIVED PERIODS OF IFR IN
HEAVIER SNOW SHOWERS. AFTER 12Z FRIDAY VFR CONDITIONS WILL RETURN.
&&
.PREV DISCUSSION... /ISSUED 306 PM MDT THU OCT 25 2012/
SHORT TERM...THE NEXT STORM SYSTEM HAS MOVED INTO WESTERN
COLORADO SPARKING OFF WIDESPREAD SNOW SHOWERS AND A FEW LIGHTNING
STRIKES OVER EASTERN UTAH. SNOW SHOWERS HAVE ALSO FORMED OVER THE
NORTHERN AND CENTRAL MOUNTAINS IN OUR FORECAST AREA WITH SLIGHTLY
MORE COVERAGE OVER PARK COUNTY AND THE SOUTHERN FOOTHILLS. THESE
SHOWERS WILL BE COME MORE WIDESPREAD IN THE NEXT COUPLE HOURS AND
SPREAD ONTO THE PLAINS. A FEW THUNDERSTORMS WILL BE POSSIBLE AS
THE LIFT AHEAD OF THIS SYSTEM IS INCREASING CAPES. EVEN THOUGH THE
UPSLOPE FLOW WILL BE QUITE LIGHT...UPWARD QG VERTICAL VELOCITY
FROM THE SURFACE UP PAST 400 MB WILL MOVE OVERHEAD BETWEEN 6 PM
AND MIDNIGHT TO HELP SNOW PRODUCTION. SNOW AMOUNTS ARE EXPECTED TO
BE BETWEEN 1-4 INCHES FORECAST AREA WIDE WITH MOST AMOUNTS AROUND
THE PALMER DIVIDE AND THE LEAST AMOUNTS OVER THE NORTHEAST CORNER.
DUE TO THE CONVECTIVE NATURE OF THE FIRST PART OF THIS STORM
HOWEVER...THERE COULD BE ISOLATED POCKETS OF HIGHER AMOUNTS.
COMPARED TO LAST NIGHT...THE SNOW WILL STICK TO THE ROADS THIS
EVENING MORE AS TEMPERATURES ALL DAY TODAY HAVE BEEN IN THE UPPER
20S TO MID 30S.
THE UPPER TROUGH AXIS WILL MOVE EAST OF THE AREA FRIDAY MORNING
WITH SUBSIDENCE SPREADING OVERHEAD STARTING MIDNIGHT TONIGHT. SNOW
WILL TAPER OFF AFTER MIDNIGHT AND SHOULD BE ALL BUT DONE BY LATE
MORNING. TEMPERATURES WILL REMAIN CHILLY TOMORROW EVEN THOUGH
SKIES SHOULD BE BREAKING UP IN THE AFTERNOON. HIGHS IN THE MID
30S OVER THE PLAINS AND IN THE UPPER 20S TO MID 30S FOR THE
MOUNTAINS ARE EXPECTED.
LONG TERM...A DRIER AND WARMER PERIOD IS EXPECTED FOR THIS LONG
RANGE FORECAST FOR COLORADO. FOLLOWING EARLY FRIDAYS STORM...A
STRONG NORTHWEST FLOW PATTERN WILL PERSIST THROUGH THE WEEKEND.
THERE WILL BE GUSTY WINDS AT TIMES OVER THE HIGHER MOUNTAINS WITH
SOME LINGERING ISOLATED SNOW SHOWERS IN THE OROGRAPHIC FLOW.
LOWER ELEVATIONS WILL BE DRY WITH MODERATING TEMPERATURES THROUGH
THE WEEKEND. FOR MONDAY THROUGH WEDNESDAY...THE NORTHWEST FLOW
WILL WEAKEN AS BROAD HIGH PRESSURE ALOFT SHIFTS TOWARDS COLORADO
WITH TEMPERATURES RETURNING TO SEASONABLE NORMALS.
AVIATION...SOME AREAS OF STRATUS STILL ALONG THE FOOTHILLS...BUT
MAINLY HAVE BROKEN UP WITH CONVECTIVE CLOUDS REPLACING THEM AS THE
NEXT SYSTEM PROVIDES LIFT OVERHEAD. CLOUDS BEGINNING TO FILL IN
AGAIN RAPIDLY HOWEVER AS SHOWERS HAVE ALREADY FORMED OVER THE
MOUNTAINS AND FOOTHILLS. KAPA AND KBJC SHOULD SEE AREAS OF SNOW
WITHIN AN HOUR OR SO...WITH KDEN FOLLOWING SOON AFTER. BEST
CHANCE OF ACCUMULATING SNOW ALONG WITH IFR/LIFR CONDITIONS IS
STILL FROM 01Z TO 06Z AT TERMINALS...WITH THE SNOW TAPERING DOWN
FROM WEST TO EAST THROUGH 12Z. SKIES WILL BE CLEARING AFTER 12Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BAKER
LONG TERM....ENTREKIN
AVIATION...RTG
AREA FORECAST DISCUSSION...UPDATED
NWS PUEBLO CO
156 PM MDT WED OCT 24 2012
.UPDATE...
UPDATED KPUB TAF AND AVIATION DISCUSSION TO KEEP SURFACE WINDS AT
KPUB EASTERLY THROUGH THE AFTERNOON INSTEAD OF BECOMING
SOUTHWESTERLY.
&&
.AVIATION...
GUSTY SOUTH TO SOUTHWEST WINDS HAVE REDEVELOPED AT COS AND ALS
AND WILL PERSIST THROUGH THE EARLY EVENING. WINDS WILL LIKELY
REMAIN EASTERLY AT PUB THROUGH THE AFTERNOON. STRONG COLD FRONT TO
MOVE ACROSS THE PLAINS THIS EVENING WITH GUSTY NORTH WINDS AND
MVFR AND LOCAL IFR CIGS SPREADING SOUTH BEHIND FRONT. FRONT LOOKS
TO CROSS THE PALMER DVD AROUND 00Z...COS AROUND 01Z...PUB AROUND
03Z AND ALL THE WAY TO THE NEW MEXICO LINE 04-05Z. COULD SEE SOME
LIGHT SNOW DEVELOPING COS AND NORTHWARD AFT 06Z. APPEARS FRONT
WILL SHOW LITTLE PENETRATION WEST OF THE SANGRE DE CRISTOS AT THE
PRESENT TIME.
&&
.PREV DISCUSSION... /ISSUED 1126 AM MDT WED OCT 24 2012/
AVIATION...
GUSTY SOUTH TO SOUTHWEST WINDS HAVE REDEVELOPED AT COS AND ALS
THIS MORNING AND WILL PERSIST THROUGH THE EARLY EVENING. SW WINDS
AT PUB LIKELY TO REDEVELOP BY MID AFTERNOON. STRONG COLD FRONT TO
MOVE ACROSS THE PLAINS THIS EVENING WITH GUSTY NORTH WINDS AND
MVFR AND LOCAL IFR CIGS SPREADING SOUTH BEHIND FRONT. FRONT LOOKS
TO CROSS THE PALMER DVD AROUND 00Z...COS AROUND 01Z...PUB AROUND
03Z AND ALL THE WAY TO THE NEW MEXICO LINE 04-05Z. COULD SEE SOME
LIGHT SNOW DEVELOPING COS AND NORTHWARD AFT 06Z. APPEARS FRONT WILL
SHOW LITTLE PENETRATION WEST OF THE SANGRE DE CRISTOS AT THE PRESENT
TIME.
PREV DISCUSSION... /ISSUED 957 AM MDT WED OCT 24 2012/
UPDATE...
UPDATED TO EXTEND THE HIGH WIND WARNING OVER THE SOUTHERN SANGRE
DE CRISTO MOUNTAINS AND SOUTHERN I-25 CORRIDOR WEST OF THE
INTERSTATE THROUGH 8 PM THIS EVENING. MOST OBSERVATIONS THIS
MORNING HAVE SHOWED WEAKER WINDS ACROSS THE WHOLE CWA WITH THE
STRONGEST WINDS CURRENTLY OVER THE LA VETA PASS REGION WHERE
WESTERLY WINDS CONTINUE TO BLOW OVER 50 MPH. LATEST MODEL AND
SATELLITE ANALYSIS INDICATES AN UPPER LEVEL JET EDGING EASTWARD
INTO COLORADO FOR THIS AFTERNOON AND WE ARE ALREADY STARTING TO
SEE TRAPPED WAVES IN THE LEE OF THE SOUTHERN MOUNTAINS. WRF CROSS
SECTIONS OVER THE SOUTHERN SANGRES ARE INDICATING WINDS STARTING
TO DUCT BACK TO THE SURFACE AFTER 18Z WITH 60 KT FLOW INTO THE
LOWER ELEVATIONS ON THE LEE SLOPES. THE WRF HAS THIS DUCTING OF
STRONG WINDS THROUGH AROUND 01Z WHEN THE MAIN JET CORE ELIMINATES
THE CRITICAL LAYER. FEEL WINDS WILL REALLY PICK UP BY NOON AND
PERSIST THROUGH THE AFTERNOON INTO THE EVENING OVER THIS REGION
WHERE GUSTS OVER 70 MPH ARE POSSIBLE IN THE MOUNTAINS AND OVER 60
MPH ALONG THE LEE SLOPES. EXTREMELY LOW HUMIDITY VALUES IN THIS
AREA WILL LEAD TO EXTREMELY DANGEROUS FIRE WEATHER CONCERNS.
ELSEWHERE...CROSS SECTIONAL ANALYSIS FURTHER NORTH ARE NOT AS
IMPRESSIVE AND INDICATE THAT MOSTLY BRUTE FORCE WINDS WILL BE THE
MAIN THREAT OVER THE NORTHERN SANGRES...WET MOUNTAINS AND VALLEY
AND LEE SLOPES NEAR THE WETMORE AREA. WINDS WILL GUST IN THIS AREA
THIS AFTERNOON...HOWEVER IT DOES NOT APPEAR AT THIS TIME THAT
STRONG MOUNTAIN WAVE ACTIVITY WILL DUCT DOWN TO THE SURFACE. FEEL
THAT THIS AREA COULD SEE A FEW GUSTS IN THE 40-50 MPH RANGE THIS
AFTERNOON BUT SHOULD REMAIN BELOW HIGH WIND WARNING CRITERIA AT
THIS TIME. EXTREME CAUTION IS ALSO ADVISED HERE AS WELL GIVEN THE
LOW HUMIDITY VALUES AND DANGEROUS FIRE WEATHER CONDITIONS. 88
PREV DISCUSSION... /ISSUED 736 AM MDT WED OCT 24 2012/
UPDATE...
UPDATED TO CANCEL HIGH WIND WARNING FOR THE WET MTS THOUGH HAVE
KEPT FOR THE SOUTHERN SANGRE DE CRISTO MTS AND IMMEDIATE ADJACENT
TERRAIN ACROSS THE SOUTHERN I-25 CORRIDOR WITH OBS STILL
INDICATING WINDS GUSTING TO 50-60 MPH AND MODELS INDICATING H7
WINDS OF 50 KTS SLOWLY DIMINISHING THROUGH 16Z. FRONT HAS MADE
IT TO THE NEW MEXICO BORDER WITH LATEST HRRR INDICATING FRONT
LIFTING BACK NORTH AND EAST SOUTH OF THE ARKANSAS RIVER THROUGH
THE LATE AFTERNOON WITH SFC LOW DEVELOPING ACROSS EASTERN LAS
ANIMAS COUNTY. THIS WOULD ALLOW FOR GUSTY SOUTHWEST WINDS AND
CRITICAL FIRE WEATHER CONDITIONS TO REDEVELOP ACROSS THE
SOUTHEASTERN MTS AND IMMEDIATE ADJACENT PLAINS LATER THIS
MORNING AND PERSISTING THROUGH THE EARLY EVENING. WILL LEAVE
CURRENT RED FLAG WARNING INTACT...HOWEVER...IF CURRENT MODELS
ARE CORRECT...MAY NOT SEE CRITICAL CONDITIONS ACROSS OTERO COUNTY
AND EASTERN PORTIONS OF PUEBLO COUNTY.
PREV DISCUSSION... /ISSUED 529 AM MDT WED OCT 24 2012/
SHORT TERM...
(TODAY AND TONIGHT)
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS CONTINUES TO
INDICATE MODERATE TO STRONG SOUTHWEST FLOW ALOFT ACROSS THE REGION
WITH BROAD UPPER TROUGH ACROSS THE WEST COAST AND GREAT BASIN. WATER
VAPOR IMAGERY ALSO INDICATING ONE EMBEDDED SHORT WAVE LIFTING OUT
ACROSS THE NORTHERN ROCKIES WITH ANOTHER WAVE TRANSLATING ACROSS THE
WEST COAST AND INTO THE GREAT BASIN. AT THE SURFACE...A WEAK FRONT
MOVED ACROSS THE EASTERN PLAINS THROUGH THE OVERNIGHT HOURS AND IS
CURRENTLY JUST NORTH OF A TRINIDAD TO SPRINGFIELD LINE. BRIEF GUSTY
NORTH WINDS HAVE BEEN NOTED BEHIND THE FRONT ALONG WITH INCREASING
LOW LEVEL MOISTURE...WITH RED CREEK RAWS INDICATING THE GUSTY
SOUTHWEST WINDS OF UP TO 60 MPH LAST EVENING BECOMING MORE EASTERLY
AND HAVE WEAKENED OVER THE PAST 2 HOURS. SW WINDS 20 TO 30 MPH WITH
GUSTS TO 60 MPH HAVE PERSISTED ACROSS THE HIGHER TERRAIN OF THE
SOUTHERN MTS WITH KPUX RADAR STILL INDICATING A HIGH WIND SIGNATURE
THROUGH THE OVERNIGHT HOURS.
TODAY...00Z MODELS HAVING A HARD TIME WITH THIS FRONT BUT 06Z AND
HIGHER RES MODELS INDICATING FRONT STALLING ACROSS THE COLORADO AND
NEW MEXICO BORDER LATER THIS MORNING AND THEN SLOWLY LIFTING BACK
NORTH AND EAST WITH A DEVELOPING SFC LOW ACROSS THE EASTERN PLAINS
AHEAD SHORT WAVE TRANSLATING ACROSS THE GREAT BASIN. SOUNDINGS STILL
INDICATING THE POTENTIAL FOR STRONG DOWNSLOPE FLOW WITH MT WAVE
ACROSS THE SOUTHERN MTS THROUGH THE EARLY MORNING AND HAVE KEPT HIGH
WIND WARNING IN PLACE THROUGH 9AM ACROSS THE WET MTS...THE SOUTHERN
SANGRE DE CRISTO MTS AND IMMEDIATE ADJACENT PLAINS OF THE SOUTHERN
I-25 CORRIDOR AND HAVE CANCELED FOR NORTHERN PORTIONS. EXPECTING
GUSTY SOUTHWEST WINDS TO REDEVELOP ACROSS ALL OF THE HIGHER
TERRAIN AND IMMEDIATE ADJACENT PLAINS THROUGH THE LATE MORNING AND
AFTERNOON WITH CRITICAL FIRE WEATHER CONDITIONS EXPECTED ONCE
AGAIN ACROSS THE SOUTHERN MTS AND SOUTHERN TIER ZONES ALONG THE
EASTERN NEW MEXICO BORDER AND HAVE KEPT CURRENT RED FLAG WARNING
IN PLACE FROM NOON TIL 7PM FOR THESE AREAS. HAVE CANCELED THE RED
FLAG WARNING FOR BENT...PROWERS AND CROWLEY COUNTIES WITH THE
INCREASED LOW LEVEL MOISTURE AND UPSLOPE FLOW EXPECTED TO DEVELOP
BEHIND THE FRONT. INCREASING MOISTURE AND LIFT AHEAD OF GREAT
BASIN SHORT WAVE AND ASSOCIATED FRONT WILL ALLOW FOR SCATTERED
SHOWERS TO DEVELOP ACROSS THE HIGHER TERRAIN OF THE CENTRAL MTS
THIS AFTERNOON.
TONIGHT...SHORT WAVE AND ASSOCIATED FRONT MARCHES ACROSS THE STATE
THIS EVENING WITH FRONT EXPECTED TO HIT THE PALMER DVD BETWEEN 00Z
AND 03Z WHICH CONTINUES ACROSS THE REST OF THE SOUTHEAST PLAINS
THROUGH EARLY THURSDAY MORNING. GUSTY NORTH WINDS OF 20-40 MPH AND
MUCH COOLER AIR TO BE USHERED INTO THE AREA BEHIND FRONT ALONG WITH
SOME GENERALLY LIGHT SNOWFALL...MAINLY TO THE HIGHER TERRAIN OF THE
PIKES PEAK REGION. -MW
LONG TERM...
(THURSDAY THROUGH NEXT TUESDAY)
LOW AND MID LEVEL FLOW GRADUALLY BECOME MORE UPSLOPE DURING THE
DAY THURSDAY AS SURFACE HIGH PRESSURE BUILDS INTO THE PLAINS BY
AFTERNOON. AREA WILL ALSO SEE INCREASING UPWARD MOTION AHEAD OF
MAIN UPPER TROUGH MOVING INTO WRN COLORADO BY THU EVENING. EXPECT
-SHRA/-SHSN TO INCREASE THROUGH THE DAY OVER THE CENTRAL MOUNTAINS
AND ACROSS THE EASTERN MOUNTAINS/PALMER DIVIDE AS UPSLOPE DEEPENS
AND LIFT INCREASES. MAX TEMPS WILL BE COLD AREA-WIDE...THOUGH
AGAIN MAV GUIDANCE LOOKS TOO COLD FOR KCOS AND KPUB. BEST WINDOW
FOR PRECIP DEVELOPS THU NIGHT AS UPPER TROUGH MOVES
ACROSS...THOUGH WEAK SURFACE/MID LEVEL UPSLOPE WILL TEMPER SNOW
AMOUNTS SOMEWHAT. STILL APPEARS BEST BET FOR ACCUMULATING SNOW
WILL BE OVER TELLER COUNTY AND ACROSS THE PALMER DIVIDE...WHERE A
FEW SPOTS COULD SEE 6 PLUS INCHES BY MIDDAY FRI. MAY NEED A WINTER
WEATHER ADVISORY HERE EVENTUALLY...THOUGH WARM GROUND MAY LIMIT
SNOW ACCUMS SOMEWHAT. REMAINDER OF THE EASTERN MOUNTAINS AND I-25
CORRIDOR WILL LIKELY SEE AT LEAST A BRIEF PERIOD OF SNOW AND SOME
LIGHT ACCUMS...WHILE PLAINS SEE ONLY SPOTTY SNOW SHOWERS WITH
LITTLE OR NO ACCUMULATION. SNOW SHOULD DIMINISH FAIRLY QUICKLY
FRIDAY AS UPPER TROUGH IS WELL EAST OF THE STATE BY MIDDAY...AND
EXPECT ONLY FLURRIES/LIGHT -SHSN BY AFTERNOON. MAX TEMPS WILL
CONTINUE ON THE COLD SIDE WITH MANY AREAS STAYING WITHIN A FEW
DEGREES OF FREEZING.
ONCE UPPER SYSTEM EXITS THE AREA FRIDAY...WEATHER BECOMES VERY
QUIET AS UPPER LEVEL RIDGE BUILDS OVER THE WEEKEND BEFORE GIVING
WAY TO WARMER WESTERLY FLOW EARLY NEXT WEEK. TEMPS WILL REMAIN
BELOW NORMAL BOTH SATURDAY AND SUNDAY AS LOW/MID LEVELS WARM ONLY
SLOWLY UNDER WEAK FLOW ALOFT. MORE SUBSTANTIAL WARMING DEVELOPS
EARLY NEXT WEEK AS WESTERLY FLOW DEVELOPS AND PUSHES WARMER AIR
BACK INTO THE STATE.
AVIATION...WEAK FRONT MOVED ACROSS THE EASTERN PLAINS OVERNIGHT
WITH NORTH WINDS TO PERSIST BEHIND SYSTEM THROUGH THE MORNING.
GUSTY SOUTH TO SOUTHWEST WINDS TO REDEVELOP AT COS AND ALS LATE
THIS MORNING AND PERSISTING THROUGH THE EARLY EVENING. SW WINDS AT
PUB LIKELY TO REDEVELOP THROUGH THE EARLY AFTERNOON AS THIS
MORNINGS FRONT SLOWLY LIFTING BACK NORTH AND EAST ACROSS THE
PLAINS. STRONGER COLD FRONT TO MOVE ACROSS THE PLAINS THIS EVENING
WITH GUSTY NORTH WINDS AND MVFR AND LOCAL IFR CIGS DEVELOPING
BEHIND FRONT. FRONT LOOKS TO HIT THE PALMER DVD AND COS BETWEEN
03Z AND 06Z AND CONTINUING ACROSS THE REST OF THE EASTERN PLAINS
THROUGH THE EARLY MORNING. COULD SEE SOME LIGHT SNOW DEVELOPING AT
COS AFT 06Z. -MW
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ074-075-087-
088.
RED FLAG WARNING UNTIL 7 PM MDT THIS EVENING FOR COZ222-225-
228>230-232-233-237.
&&
$$
50/88
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1126 AM MDT WED OCT 24 2012
.AVIATION...
GUSTY SOUTH TO SOUTHWEST WINDS HAVE REDEVELOPED AT COS AND ALS
THIS MORNING AND WILL PERSIST THROUGH THE EARLY EVENING. SW WINDS
AT PUB LIKELY TO REDEVELOP BY MID AFTERNOON. STRONG COLD FRONT TO
MOVE ACROSS THE PLAINS THIS EVENING WITH GUSTY NORTH WINDS AND
MVFR AND LOCAL IFR CIGS SPREADING SOUTH BEHIND FRONT. FRONT LOOKS
TO CROSS THE PALMER DVD AROUND 00Z...COS AROUND 01Z...PUB AROUND
03Z AND ALL THE WAY TO THE NEW MEXICO LINE 04-05Z. COULD SEE SOME
LIGHT SNOW DEVELOPING COS AND NORTHWARD AFT 06Z. APPEARS FRONT WILL
SHOW LITTLE PENETRATION WEST OF THE SANGRE DE CRISTOS AT THE PRESENT
TIME.
&&
.PREV DISCUSSION... /ISSUED 957 AM MDT WED OCT 24 2012/
UPDATE...
UPDATED TO EXTEND THE HIGH WIND WARNING OVER THE SOUTHERN SANGRE
DE CRISTO MOUNTAINS AND SOUTHERN I-25 CORRIDOR WEST OF THE
INTERSTATE THROUGH 8 PM THIS EVENING. MOST OBSERVATIONS THIS
MORNING HAVE SHOWED WEAKER WINDS ACROSS THE WHOLE CWA WITH THE
STRONGEST WINDS CURRENTLY OVER THE LA VETA PASS REGION WHERE
WESTERLY WINDS CONTINUE TO BLOW OVER 50 MPH. LATEST MODEL AND
SATELLITE ANALYSIS INDICATES AN UPPER LEVEL JET EDGING EASTWARD
INTO COLORADO FOR THIS AFTERNOON AND WE ARE ALREADY STARTING TO
SEE TRAPPED WAVES IN THE LEE OF THE SOUTHERN MOUNTAINS. WRF CROSS
SECTIONS OVER THE SOUTHERN SANGRES ARE INDICATING WINDS STARTING
TO DUCT BACK TO THE SURFACE AFTER 18Z WITH 60 KT FLOW INTO THE
LOWER ELEVATIONS ON THE LEE SLOPES. THE WRF HAS THIS DUCTING OF
STRONG WINDS THROUGH AROUND 01Z WHEN THE MAIN JET CORE ELIMINATES
THE CRITICAL LAYER. FEEL WINDS WILL REALLY PICK UP BY NOON AND
PERSIST THROUGH THE AFTERNOON INTO THE EVENING OVER THIS REGION
WHERE GUSTS OVER 70 MPH ARE POSSIBLE IN THE MOUNTAINS AND OVER 60
MPH ALONG THE LEE SLOPES. EXTREMELY LOW HUMIDITY VALUES IN THIS
AREA WILL LEAD TO EXTREMELY DANGEROUS FIRE WEATHER CONCERNS.
ELSEWHERE...CROSS SECTIONAL ANALYSIS FURTHER NORTH ARE NOT AS
IMPRESSIVE AND INDICATE THAT MOSTLY BRUTE FORCE WINDS WILL BE THE
MAIN THREAT OVER THE NORTHERN SANGRES...WET MOUNTAINS AND VALLEY
AND LEE SLOPES NEAR THE WETMORE AREA. WINDS WILL GUST IN THIS AREA
THIS AFTERNOON...HOWEVER IT DOES NOT APPEAR AT THIS TIME THAT
STRONG MOUNTAIN WAVE ACTIVITY WILL DUCT DOWN TO THE SURFACE. FEEL
THAT THIS AREA COULD SEE A FEW GUSTS IN THE 40-50 MPH RANGE THIS
AFTERNOON BUT SHOULD REMAIN BELOW HIGH WIND WARNING CRITERIA AT
THIS TIME. EXTREME CAUTION IS ALSO ADVISED HERE AS WELL GIVEN THE
LOW HUMIDITY VALUES AND DANGEROUS FIRE WEATHER CONDITIONS. 88
PREV DISCUSSION... /ISSUED 736 AM MDT WED OCT 24 2012/
UPDATE...
UPDATED TO CANCEL HIGH WIND WARNING FOR THE WET MTS THOUGH HAVE
KEPT FOR THE SOUTHERN SANGRE DE CRISTO MTS AND IMMEDIATE ADJACENT
TERRAIN ACROSS THE SOUTHERN I-25 CORRIDOR WITH OBS STILL
INDICATING WINDS GUSTING TO 50-60 MPH AND MODELS INDICATING H7
WINDS OF 50 KTS SLOWLY DIMINISHING THROUGH 16Z. FRONT HAS MADE
IT TO THE NEW MEXICO BORDER WITH LATEST HRRR INDICATING FRONT
LIFTING BACK NORTH AND EAST SOUTH OF THE ARKANSAS RIVER THROUGH
THE LATE AFTERNOON WITH SFC LOW DEVELOPING ACROSS EASTERN LAS
ANIMAS COUNTY. THIS WOULD ALLOW FOR GUSTY SOUTHWEST WINDS AND
CRITICAL FIRE WEATHER CONDITIONS TO REDEVELOP ACROSS THE
SOUTHEASTERN MTS AND IMMEDIATE ADJACENT PLAINS LATER THIS
MORNING AND PERSISTING THROUGH THE EARLY EVENING. WILL LEAVE
CURRENT RED FLAG WARNING INTACT...HOWEVER...IF CURRENT MODELS
ARE CORRECT...MAY NOT SEE CRITICAL CONDITIONS ACROSS OTERO COUNTY
AND EASTERN PORTIONS OF PUEBLO COUNTY.
PREV DISCUSSION... /ISSUED 529 AM MDT WED OCT 24 2012/
SHORT TERM...
(TODAY AND TONIGHT)
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS CONTINUES TO
INDICATE MODERATE TO STRONG SOUTHWEST FLOW ALOFT ACROSS THE REGION
WITH BROAD UPPER TROUGH ACROSS THE WEST COAST AND GREAT BASIN. WATER
VAPOR IMAGERY ALSO INDICATING ONE EMBEDDED SHORT WAVE LIFTING OUT
ACROSS THE NORTHERN ROCKIES WITH ANOTHER WAVE TRANSLATING ACROSS THE
WEST COAST AND INTO THE GREAT BASIN. AT THE SURFACE...A WEAK FRONT
MOVED ACROSS THE EASTERN PLAINS THROUGH THE OVERNIGHT HOURS AND IS
CURRENTLY JUST NORTH OF A TRINIDAD TO SPRINGFIELD LINE. BRIEF GUSTY
NORTH WINDS HAVE BEEN NOTED BEHIND THE FRONT ALONG WITH INCREASING
LOW LEVEL MOISTURE...WITH RED CREEK RAWS INDICATING THE GUSTY
SOUTHWEST WINDS OF UP TO 60 MPH LAST EVENING BECOMING MORE EASTERLY
AND HAVE WEAKENED OVER THE PAST 2 HOURS. SW WINDS 20 TO 30 MPH WITH
GUSTS TO 60 MPH HAVE PERSISTED ACROSS THE HIGHER TERRAIN OF THE
SOUTHERN MTS WITH KPUX RADAR STILL INDICATING A HIGH WIND SIGNATURE
THROUGH THE OVERNIGHT HOURS.
TODAY...00Z MODELS HAVING A HARD TIME WITH THIS FRONT BUT 06Z AND
HIGHER RES MODELS INDICATING FRONT STALLING ACROSS THE COLORADO AND
NEW MEXICO BORDER LATER THIS MORNING AND THEN SLOWLY LIFTING BACK
NORTH AND EAST WITH A DEVELOPING SFC LOW ACROSS THE EASTERN PLAINS
AHEAD SHORT WAVE TRANSLATING ACROSS THE GREAT BASIN. SOUNDINGS STILL
INDICATING THE POTENTIAL FOR STRONG DOWNSLOPE FLOW WITH MT WAVE
ACROSS THE SOUTHERN MTS THROUGH THE EARLY MORNING AND HAVE KEPT HIGH
WIND WARNING IN PLACE THROUGH 9AM ACROSS THE WET MTS...THE SOUTHERN
SANGRE DE CRISTO MTS AND IMMEDIATE ADJACENT PLAINS OF THE SOUTHERN
I-25 CORRIDOR AND HAVE CANCELED FOR NORTHERN PORTIONS. EXPECTING
GUSTY SOUTHWEST WINDS TO REDEVELOP ACROSS ALL OF THE HIGHER
TERRAIN AND IMMEDIATE ADJACENT PLAINS THROUGH THE LATE MORNING AND
AFTERNOON WITH CRITICAL FIRE WEATHER CONDITIONS EXPECTED ONCE
AGAIN ACROSS THE SOUTHERN MTS AND SOUTHERN TIER ZONES ALONG THE
EASTERN NEW MEXICO BORDER AND HAVE KEPT CURRENT RED FLAG WARNING
IN PLACE FROM NOON TIL 7PM FOR THESE AREAS. HAVE CANCELED THE RED
FLAG WARNING FOR BENT...PROWERS AND CROWLEY COUNTIES WITH THE
INCREASED LOW LEVEL MOISTURE AND UPSLOPE FLOW EXPECTED TO DEVELOP
BEHIND THE FRONT. INCREASING MOISTURE AND LIFT AHEAD OF GREAT
BASIN SHORT WAVE AND ASSOCIATED FRONT WILL ALLOW FOR SCATTERED
SHOWERS TO DEVELOP ACROSS THE HIGHER TERRAIN OF THE CENTRAL MTS
THIS AFTERNOON.
TONIGHT...SHORT WAVE AND ASSOCIATED FRONT MARCHES ACROSS THE STATE
THIS EVENING WITH FRONT EXPECTED TO HIT THE PALMER DVD BETWEEN 00Z
AND 03Z WHICH CONTINUES ACROSS THE REST OF THE SOUTHEAST PLAINS
THROUGH EARLY THURSDAY MORNING. GUSTY NORTH WINDS OF 20-40 MPH AND
MUCH COOLER AIR TO BE USHERED INTO THE AREA BEHIND FRONT ALONG WITH
SOME GENERALLY LIGHT SNOWFALL...MAINLY TO THE HIGHER TERRAIN OF THE
PIKES PEAK REGION. -MW
LONG TERM...
(THURSDAY THROUGH NEXT TUESDAY)
LOW AND MID LEVEL FLOW GRADUALLY BECOME MORE UPSLOPE DURING THE
DAY THURSDAY AS SURFACE HIGH PRESSURE BUILDS INTO THE PLAINS BY
AFTERNOON. AREA WILL ALSO SEE INCREASING UPWARD MOTION AHEAD OF
MAIN UPPER TROUGH MOVING INTO WRN COLORADO BY THU EVENING. EXPECT
-SHRA/-SHSN TO INCREASE THROUGH THE DAY OVER THE CENTRAL MOUNTAINS
AND ACROSS THE EASTERN MOUNTAINS/PALMER DIVIDE AS UPSLOPE DEEPENS
AND LIFT INCREASES. MAX TEMPS WILL BE COLD AREA-WIDE...THOUGH
AGAIN MAV GUIDANCE LOOKS TOO COLD FOR KCOS AND KPUB. BEST WINDOW
FOR PRECIP DEVELOPS THU NIGHT AS UPPER TROUGH MOVES
ACROSS...THOUGH WEAK SURFACE/MID LEVEL UPSLOPE WILL TEMPER SNOW
AMOUNTS SOMEWHAT. STILL APPEARS BEST BET FOR ACCUMULATING SNOW
WILL BE OVER TELLER COUNTY AND ACROSS THE PALMER DIVIDE...WHERE A
FEW SPOTS COULD SEE 6 PLUS INCHES BY MIDDAY FRI. MAY NEED A WINTER
WEATHER ADVISORY HERE EVENTUALLY...THOUGH WARM GROUND MAY LIMIT
SNOW ACCUMS SOMEWHAT. REMAINDER OF THE EASTERN MOUNTAINS AND I-25
CORRIDOR WILL LIKELY SEE AT LEAST A BRIEF PERIOD OF SNOW AND SOME
LIGHT ACCUMS...WHILE PLAINS SEE ONLY SPOTTY SNOW SHOWERS WITH
LITTLE OR NO ACCUMULATION. SNOW SHOULD DIMINISH FAIRLY QUICKLY
FRIDAY AS UPPER TROUGH IS WELL EAST OF THE STATE BY MIDDAY...AND
EXPECT ONLY FLURRIES/LIGHT -SHSN BY AFTERNOON. MAX TEMPS WILL
CONTINUE ON THE COLD SIDE WITH MANY AREAS STAYING WITHIN A FEW
DEGREES OF FREEZING.
ONCE UPPER SYSTEM EXITS THE AREA FRIDAY...WEATHER BECOMES VERY
QUIET AS UPPER LEVEL RIDGE BUILDS OVER THE WEEKEND BEFORE GIVING
WAY TO WARMER WESTERLY FLOW EARLY NEXT WEEK. TEMPS WILL REMAIN
BELOW NORMAL BOTH SATURDAY AND SUNDAY AS LOW/MID LEVELS WARM ONLY
SLOWLY UNDER WEAK FLOW ALOFT. MORE SUBSTANTIAL WARMING DEVELOPS
EARLY NEXT WEEK AS WESTERLY FLOW DEVELOPS AND PUSHES WARMER AIR
BACK INTO THE STATE.
AVIATION...WEAK FRONT MOVED ACROSS THE EASTERN PLAINS OVERNIGHT
WITH NORTH WINDS TO PERSIST BEHIND SYSTEM THROUGH THE MORNING.
GUSTY SOUTH TO SOUTHWEST WINDS TO REDEVELOP AT COS AND ALS LATE
THIS MORNING AND PERSISTING THROUGH THE EARLY EVENING. SW WINDS AT
PUB LIKELY TO REDEVELOP THROUGH THE EARLY AFTERNOON AS THIS
MORNINGS FRONT SLOWLY LIFTING BACK NORTH AND EAST ACROSS THE
PLAINS. STRONGER COLD FRONT TO MOVE ACROSS THE PLAINS THIS EVENING
WITH GUSTY NORTH WINDS AND MVFR AND LOCAL IFR CIGS DEVELOPING
BEHIND FRONT. FRONT LOOKS TO HIT THE PALMER DVD AND COS BETWEEN
03Z AND 06Z AND CONTINUING ACROSS THE REST OF THE EASTERN PLAINS
THROUGH THE EARLY MORNING. COULD SEE SOME LIGHT SNOW DEVELOPING AT
COS AFT 06Z. -MW
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ074-075-087-
088.
RED FLAG WARNING UNTIL 7 PM MDT THIS EVENING FOR COZ222-225-
228>230-232-233-237.
&&
$$
50/88
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1058 AM MDT WED OCT 24 2012
.UPDATE...
ISSUED AT 1058 AM MDT WED OCT 24 2012
A WINTRY MIX OF RAIN...WET SNOW AND SNOW OVER NORTHEAST UTAH WILL
BE SPREADING ACROSS MOFFAT COUNTY OF NW COLORADO TODAY. THIS
ACTIVITY WILL CONTINUE TO PROGRESS SOUTH AND EAST THIS EVENING.
PROGRESSIVE SHORT WAVE PUSHES THE BAROCLINIC ZONE EAST THIS
AFTERNOON AND EVENING ACROSS NW COLORADO. RAPIDLY CHANGING WEATHER
FROM RELATIVELY MILD CONDITIONS TO MIXTURE OF RAIN AND WET
SNOW...TURNING TO ALL SNOW AS COLDER AIR ADVECTS ACROSS THE REGION
WARRANTS EXPANSION OF WINTER WEATHER ADVISORY. TO COMPOUND THE
FAVORABLE DYNAMICAL FORCING...CONDITIONAL INSTABILITY ADDS THE
CONVECTIVE POTENTIAL FOR ISOLATED THUNDERSTORMS AND POSSIBLY
ENHANCE SNOWFALL RATES ALONG THE LEADING EDGE OF THE BAROCLINIC
ZONE. IF CURRENT TREND HOLDS...WILL BE ADDING THE GRAND MESA AND
THE TAVAPUTS/ROAN PLATEAU TO THE WINTER WEATHER ADVISORY. WILL
WATCH HOW THE SNOW EVOLVES INTO EARLY AFTERNOON AND WAIT FOR THE
FULL 12Z MODEL SUITE BEFORE EXPANDING OR EXTENDING ANY WINTER
WEATHER ADVISORIES.
FOR SOUTHEAST UTAH AND SOUTHWEST COLORADO...THE HRRR MODELS
INDICATE STRONG GUSTY WINDS ACROSS THIS AREA. CANNOT ARGUE WITH
THIS GIVEN INTREPRETATION OF THE WATER VAPOR LOOP THAT SHOWS
DARKENING AREA OF PACIFIC JET THAT PUNCHES OVERHEAD. COMBINED WITH
PRONOUNCED FALLING SURFACE PRESSURE OVER ERN COLORADO AND THEREBY
INCREASING THE WEST TO EAST GRADIENT FLOW...HOISTED WIND ADVISORY
FOR MUCH OF THE SOUTHERN AREA. SOME MOUNTAIN WAVE ACTIVITY IS
POSSIBLE AND HAVE INCLUDED THE UNCOMPAHGRE PLATEAU AND NWRN SAN
JUAN MOUNTAINS WHERE STRONG WINDS MAY IMPACT RED MOUNTAIN
PASS...CERRO SUMMIT...AND RIDGWAY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 416 AM MDT WED OCT 24 2012
A SURFACE FRONT LAY STALLED ALONG A 20N KCNY TO JUST SOUTH OF KCAG
LINE EARLY THIS MORNING. MOISTURE OVERRUNNING THE FRONT IN
SOUTHWESTERLY FLOW RESULTED IN A BROAD MID AND HIGH LEVEL CLOUD
SHIELD OVER NORTHEAST UTAH AND NORTHWEST COLORADO. KGJX RADAR WAS
PICKING UP SOME LIGHT PRECIPITATION JUST NORTH OF THE FRONT THOUGH
SUSPECT MUCH OF WHAT HAS BEEN DETECTED IS VIRGA. SUSPECT SNOW IS
FALLING OVER THE EASTERN UINTA MOUNTAINS THOUGH DATA FROM THE
SNOTEL SITES TOO NOISY TO ASCERTAIN THIS FOR CERTAIN.
TODAY: A VIGOROUS SHORTWAVE WILL EJECT EASTWARD THROUGH THE BASE
OF THE BROAD WEST COAST TROUGH LATER IN THE DAY. THIS WILL DRIVE
THE COLD FRONT DEEP INTO SOUTHEAST UTAH AND ABOUT TWO THIRDS OF
THE WAY THROUGH WESTERN COLORADO. FRONTOGENETIC FORCING ALONG THE
FRONT COMBINED WITH NEGATIVE DIV-Q ALOFT WILL PROVIDE LIFT FOR
MORE WIDESPREAD SHOWER ACTIVITY...ESPECIALLY ACROSS THE NORTH THIS
MORNING...SPREADING SOUTHWARD INTO THE CENTRAL PORTION OF THE
FORECAST AREA DURING THE AFTERNOON. MODELS INDICATED ATMOSPHERE
ALONG THE FRONTAL BOUNDARY WILL BE CONDITIONALLY UNSTABLE SO ADDED
MENTION OF ISOLATED STORMS IN ITS VICINITY. SNOW...ALREADY ONGOING
OVER THE EASTERN UINTA MOUNTAINS...WILL BECOME WIDESPREAD OVER THE
NORTHERN COLORADO MOUNTAINS AS WELL THE GORE AND ELK MOUNTAINS OF
CENTRAL COLORADO. IN NORTHERN COLORADO...SNOW LEVELS BEGIN AROUND
9000 FEET INITIALLY...FALLING TO AROUND 8000 FEET BEHIND THE FRONT
DURING THE AFTERNOON. SNOW LEVELS WERE ALREADY AT THE BASE OF THE
EASTERN UINTAS. SOUTHWEST WINDS WILL CONTINUE TO BE STRONG AHEAD
OF THE FRONT BUT SHOULD REMAIN BELOW ADVISORY CRITERIA. MOISTURE
WILL BE SLOW TO REACH THE SOUTHERN MOUNTAINS TODAY...SO KEPT POPS
TO ISOLATED AND LOW END SCATTERED AND LEFT OUT ANY REAL CHANCES
FOR THE LOWER ELEVATIONS. WINTER WEATHER ADVISORIES APPEARED ON
TRACK SO MADE NO CHANGES.
TEMPERATURES WILL BE MARKEDLY COOLER TODAY IN RESPONSE TO COLD
AIR ADVECTION...INCREASED CLOUD COVER AND SHOWER ACTIVITY. FAVORED
THE COLDER MET GUIDANCE ACROSS THE NORTH.
TONIGHT-FRIDAY: THE STORM WILL BE WELL UNDERWAY ACROSS THE
FORECAST AREA THIS EVENING AS THE COLD FRONT PASSES OVER THE
SOUTHERN THIRD AND EXITS THE CWA BEFORE MIDNIGHT. THE FRONT WILL
BRING THE BEST CHANCE OF SHOWERS TO THE SAN JUANS THROUGH THE
EVENING. HOWEVER WITH LIMITED MOISTURE THAT FAR SOUTH...DO NOT
EXPECT MUCH MORE THAN SCATTERED ACTIVITY MAINLY TIMED WITH THE
FRONT...AND MAINLY OVER THE HIGHER PEAKS. OTHERWISE THE STORM WILL
TRANSITION INTO THE COLD PHASE AS THE MAIN TROUGH AND THE COLD
POOL ALOFT MOVE OVERHEAD. HOWEVER WE WILL SEE SOME DRIER AIR
BEGINNING TO FILTER IN FROM THE WEST BY EARLY THIS EVENING. SO
ACTIVITY WILL BEGIN TO DIMINISH OVER NORTHEAST AND EAST-CENTRAL UT
INITIALLY...AND THEN OVER FAR WESTERN CO MID TO LATE EVENING. THIS
TREND WILL CONTINUE OVERNIGHT WITH PRECIPITATION BECOMING
CONCENTRATED OVER THE NORTHERN AND CENTRAL MOUNTAINS...ESPECIALLY
ALONG THE DIVIDE. ALSO OROGRAPHIC SHOWERS WILL FAVOR NORTHWEST
FACING SLOPES. SNOW LEVELS WILL QUICKLY FALL AS THE SUN SETS...
DROPPING INTO THE VALLEYS. HOWEVER FOR THE LOWER VALLEYS...
PRECIPITATION WILL HAVE GREATLY DIMINISHED OR ENDED BY THE TIME IT
WILL BE COLD ENOUGH FOR SNOW. A COLD NIGHT IS EXPECTED BEHIND THE
FRONT WITH VALUES AROUND 6-12 COOLER THAN THIS MORNING`S LOWS.
ACTIVITY WILL WIND DOWN LATE TONIGHT AND EARLY THURSDAY BEFORE THE
UPPER JET CARRIES ANOTHER REINFORCING COLD SHOT INTO THE BASE OF
THE TROUGH THU AFTERNOON/EVENING. AS THIS WAVE OF COLDER AIR MOVES
OVER THE AREA INSTABILITY WILL INCREASE...KEEPING SHOWERS LIKELY
OVER THE FAVORED NORTHERN MOUNTAINS. AT 500 MB THE GFS BRINGS THE
-28C ISOTHERM OVER GRAND JUNCTION BY MIDNIGHT. THE NAM IS EVEN
COLDER WITH AN AREA OF -31C DIPPING ACROSS OUR NORTHERN EDGE.
HOWEVER ON THE LIMITING SIDE...MOISTURE WILL CONTINUE TO DIMINISH
THROUGH THE AFTERNOON SO ONLY LIGHT ACCUMULATIONS WILL BE EXPECTED
THROUGH THU/THU NIGHT. THE COOLING TREND CONTINUES FOR ANOTHER
DROP IN BOTH THE HIGH LOW TEMPERATURES.
A DRIER NORTHWEST FLOW WILL DOMINATE ON FRIDAY. CONDITIONS WILL BE
COLD AND DRY OTHER THAN SOME OROGRAPHIC SHOWERS OVER THE NORTHWEST
SLOPES OF THE NORTHERN AND CENTRAL MOUNTAINS.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 416 AM MDT WED OCT 24 2012
NORTHWEST FLOW CONTINUES ACROSS THE AREA THIS WEEKEND BEFORE FLAT
RIDGING FORMS OVER THE REGION EARLY NEXT WEEK. SIGNIFICANT WEATHER
IS NOT EXPECTED DURING THIS PERIOD THOUGH BOTH MODELS INDICATED
THERE MAY BE A FEW DISTURBANCES BRUSHING NORTHERN COLORADO DURING
THIS PERIOD POSSIBLY BRINGING SOME LIGHT SHOWERS TO THE MOUNTAINS.
HOWEVER...TIMING BETWEEN THE MODELS WAS POOR AND ITS UNLIKELY THAT
THE MODELS HAVE THE SKILL TO RESOLVE THESE FAST MOVING MINOR
PERTURBATIONS THAT FAR OUT. THEREFORE...LEFT THE LOW POP VALUES
GENERATED FROM BLENDED MODELS ACROSS THE NORTHERN MOUNTAINS DURING
MUCH OF THE PERIOD.
SEASON ENDING FREEZE FOR SOUTHEAST UTAH...THE GRAND VALLEY AND THE
LOWER ELEVATIONS OF MONTEZUMA AND DOLORES COUNTIES REMAINS A
POSSIBILITY SATURDAY MORNING. A WARMING TREND TAKES OVER THIS
WEEKEND WITH TEMPERATURES CLIMBING BACK TO SEASONAL NORMS EARLY
NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1058 AM MDT WED OCT 24 2012
MECHANICAL TURBULENCE...LOCAL LOW LEVEL WIND SHEAR...AND
WIDESPREAD WINDS OF 25KT WITH OCCASIONAL GUSTS TO 35-40KT WILL
IMPACT AIRFIELDS SOUTH OF INTERSTATE 70. THESE WINDS WILL TAPER
OFF AFTER 01Z THIS EVENING.
FOR NORTHEAST UTAH AND NORTHWEST COLORADO...WIDESPREAD RASN CIGS
AOB OVC030 WITH LOCAL CIGS AOB BKN010 VIS BLO 3SM WILL SPREAD EAST
AND SOUTH AND IMPACT THE FOLLOWING AIRFIELDS...KVEL...KCAG...KEEO...KHDN
AND KSBS. ICING WILL BE A DISTINCT POSSIBILITY AS TEMPERATURES
WILL FALL BELOW FREEZING TONIGHT...ALLOWING FOR ANY MELTED PRECIPITATION
TO FREEZE.
IMPROVING CONDITIONS ARE EXPECTED AFTER 06Z TONIGHT...BUT EXPECT
LINGERING FLURRIES AND PARTIAL MOUNTAIN OBSCURATIONS TO PERSIST
ACROSS THE NRN MOUNTAINS THROUGH THURSDAY MORNING.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WIND ADVISORY UNTIL 7 PM MDT THIS EVENING FOR COZ011-014-017-018-
020>023.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR COZ001-
002-005.
WINTER WEATHER ADVISORY UNTIL 6 AM MDT THURSDAY FOR COZ004-010-
013.
UT...WIND ADVISORY UNTIL 7 PM MDT THIS EVENING FOR UTZ022-027-029.
WINTER WEATHER ADVISORY UNTIL 9 PM MDT THIS EVENING FOR UTZ023.
&&
$$
UPDATE...PF
SHORT TERM...NL/EH
LONG TERM...NL
AVIATION...PF
AREA FORECAST DISCUSSION...UPDATED
NWS PUEBLO CO
957 AM MDT WED OCT 24 2012
.UPDATE...
UPDATED TO EXTEND THE HIGH WIND WARNING OVER THE SOUTHERN SANGRE
DE CRISTO MOUNTAINS AND SOUTHERN I-25 CORRIDOR WEST OF THE
INTERSTATE THROUGH 8 PM THIS EVENING. MOST OBSERVATIONS THIS
MORNING HAVE SHOWED WEAKER WINDS ACROSS THE WHOLE CWA WITH THE
STRONGEST WINDS CURRENTLY OVER THE LA VETA PASS REGION WHERE
WESTERLY WINDS CONTINUE TO BLOW OVER 50 MPH. LATEST MODEL AND
SATELLITE ANALYSIS INDICATES AN UPPER LEVEL JET EDGING EASTWARD
INTO COLORADO FOR THIS AFTERNOON AND WE ARE ALREADY STARTING TO
SEE TRAPPED WAVES IN THE LEE OF THE SOUTHERN MOUNTAINS. WRF CROSS
SECTIONS OVER THE SOUTHERN SANGRES ARE INDICATING WINDS STARTING
TO DUCT BACK TO THE SURFACE AFTER 18Z WITH 60 KT FLOW INTO THE
LOWER ELEVATIONS ON THE LEE SLOPES. THE WRF HAS THIS DUCTING OF
STRONG WINDS THROUGH AROUND 01Z WHEN THE MAIN JET CORE ELIMINATES
THE CRITICAL LAYER. FEEL WINDS WILL REALLY PICK UP BY NOON AND
PERSIST THROUGH THE AFTERNOON INTO THE EVENING OVER THIS REGION
WHERE GUSTS OVER 70 MPH ARE POSSIBLE IN THE MOUNTAINS AND OVER 60
MPH ALONG THE LEE SLOPES. EXTREMELY LOW HUMIDITY VALUES IN THIS
AREA WILL LEAD TO EXTREMELY DANGEROUS FIRE WEATHER CONCERNS.
ELSEWHERE...CROSS SECTIONAL ANALYSIS FURTHER NORTH ARE NOT AS
IMPRESSIVE AND INDICATE THAT MOSTLY BRUTE FORCE WINDS WILL BE THE
MAIN THREAT OVER THE NORTHERN SANGRES...WET MOUNTAINS AND VALLEY
AND LEE SLOPES NEAR THE WETMORE AREA. WINDS WILL GUST IN THIS AREA
THIS AFTERNOON...HOWEVER IT DOES NOT APPEAR AT THIS TIME THAT
STRONG MOUNTAIN WAVE ACTIVITY WILL DUCT DOWN TO THE SURFACE. FEEL
THAT THIS AREA COULD SEE A FEW GUSTS IN THE 40-50 MPH RANGE THIS
AFTERNOON BUT SHOULD REMAIN BELOW HIGH WIND WARNING CRITERIA AT
THIS TIME. EXTREME CAUTION IS ALSO ADVISED HERE AS WELL GIVEN THE
LOW HUMIDITY VALUES AND DANGEROUS FIRE WEATHER CONDITIONS. MOZLEY
&&
.PREV DISCUSSION... /ISSUED 736 AM MDT WED OCT 24 2012/
UPDATE...
UPDATED TO CANCEL HIGH WIND WARNING FOR THE WET MTS THOUGH HAVE
KEPT FOR THE SOUTHERN SANGRE DE CRISTO MTS AND IMMEDIATE ADJACENT
TERRAIN ACROSS THE SOUTHERN I-25 CORRIDOR WITH OBS STILL
INDICATING WINDS GUSTING TO 50-60 MPH AND MODELS INDICATING H7
WINDS OF 50 KTS SLOWLY DIMINISHING THROUGH 16Z. FRONT HAS MADE
IT TO THE NEW MEXICO BORDER WITH LATEST HRRR INDICATING FRONT
LIFTING BACK NORTH AND EAST SOUTH OF THE ARKANSAS RIVER THROUGH
THE LATE AFTERNOON WITH SFC LOW DEVELOPING ACROSS EASTERN LAS
ANIMAS COUNTY. THIS WOULD ALLOW FOR GUSTY SOUTHWEST WINDS AND
CRITICAL FIRE WEATHER CONDITIONS TO REDEVELOP ACROSS THE
SOUTHEASTERN MTS AND IMMEDIATE ADJACENT PLAINS LATER THIS
MORNING AND PERSISTING THROUGH THE EARLY EVENING. WILL LEAVE
CURRENT RED FLAG WARNING INTACT...HOWEVER...IF CURRENT MODELS
ARE CORRECT...MAY NOT SEE CRITICAL CONDITIONS ACROSS OTERO COUNTY
AND EASTERN PORTIONS OF PUEBLO COUNTY.
PREV DISCUSSION... /ISSUED 529 AM MDT WED OCT 24 2012/
SHORT TERM...
(TODAY AND TONIGHT)
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS CONTINUES TO
INDICATE MODERATE TO STRONG SOUTHWEST FLOW ALOFT ACROSS THE REGION
WITH BROAD UPPER TROUGH ACROSS THE WEST COAST AND GREAT BASIN. WATER
VAPOR IMAGERY ALSO INDICATING ONE EMBEDDED SHORT WAVE LIFTING OUT
ACROSS THE NORTHERN ROCKIES WITH ANOTHER WAVE TRANSLATING ACROSS THE
WEST COAST AND INTO THE GREAT BASIN. AT THE SURFACE...A WEAK FRONT
MOVED ACROSS THE EASTERN PLAINS THROUGH THE OVERNIGHT HOURS AND IS
CURRENTLY JUST NORTH OF A TRINIDAD TO SPRINGFIELD LINE. BRIEF GUSTY
NORTH WINDS HAVE BEEN NOTED BEHIND THE FRONT ALONG WITH INCREASING
LOW LEVEL MOISTURE...WITH RED CREEK RAWS INDICATING THE GUSTY
SOUTHWEST WINDS OF UP TO 60 MPH LAST EVENING BECOMING MORE EASTERLY
AND HAVE WEAKENED OVER THE PAST 2 HOURS. SW WINDS 20 TO 30 MPH WITH
GUSTS TO 60 MPH HAVE PERSISTED ACROSS THE HIGHER TERRAIN OF THE
SOUTHERN MTS WITH KPUX RADAR STILL INDICATING A HIGH WIND SIGNATURE
THROUGH THE OVERNIGHT HOURS.
TODAY...00Z MODELS HAVING A HARD TIME WITH THIS FRONT BUT 06Z AND
HIGHER RES MODELS INDICATING FRONT STALLING ACROSS THE COLORADO AND
NEW MEXICO BORDER LATER THIS MORNING AND THEN SLOWLY LIFTING BACK
NORTH AND EAST WITH A DEVELOPING SFC LOW ACROSS THE EASTERN PLAINS
AHEAD SHORT WAVE TRANSLATING ACROSS THE GREAT BASIN. SOUNDINGS STILL
INDICATING THE POTENTIAL FOR STRONG DOWNSLOPE FLOW WITH MT WAVE
ACROSS THE SOUTHERN MTS THROUGH THE EARLY MORNING AND HAVE KEPT HIGH
WIND WARNING IN PLACE THROUGH 9AM ACROSS THE WET MTS...THE SOUTHERN
SANGRE DE CRISTO MTS AND IMMEDIATE ADJACENT PLAINS OF THE SOUTHERN
I-25 CORRIDOR AND HAVE CANCELED FOR NORTHERN PORTIONS. EXPECTING
GUSTY SOUTHWEST WINDS TO REDEVELOP ACROSS ALL OF THE HIGHER
TERRAIN AND IMMEDIATE ADJACENT PLAINS THROUGH THE LATE MORNING AND
AFTERNOON WITH CRITICAL FIRE WEATHER CONDITIONS EXPECTED ONCE
AGAIN ACROSS THE SOUTHERN MTS AND SOUTHERN TIER ZONES ALONG THE
EASTERN NEW MEXICO BORDER AND HAVE KEPT CURRENT RED FLAG WARNING
IN PLACE FROM NOON TIL 7PM FOR THESE AREAS. HAVE CANCELED THE RED
FLAG WARNING FOR BENT...PROWERS AND CROWLEY COUNTIES WITH THE
INCREASED LOW LEVEL MOISTURE AND UPSLOPE FLOW EXPECTED TO DEVELOP
BEHIND THE FRONT. INCREASING MOISTURE AND LIFT AHEAD OF GREAT
BASIN SHORT WAVE AND ASSOCIATED FRONT WILL ALLOW FOR SCATTERED
SHOWERS TO DEVELOP ACROSS THE HIGHER TERRAIN OF THE CENTRAL MTS
THIS AFTERNOON.
TONIGHT...SHORT WAVE AND ASSOCIATED FRONT MARCHES ACROSS THE STATE
THIS EVENING WITH FRONT EXPECTED TO HIT THE PALMER DVD BETWEEN 00Z
AND 03Z WHICH CONTINUES ACROSS THE REST OF THE SOUTHEAST PLAINS
THROUGH EARLY THURSDAY MORNING. GUSTY NORTH WINDS OF 20-40 MPH AND
MUCH COOLER AIR TO BE USHERED INTO THE AREA BEHIND FRONT ALONG WITH
SOME GENERALLY LIGHT SNOWFALL...MAINLY TO THE HIGHER TERRAIN OF THE
PIKES PEAK REGION. -MW
LONG TERM...
(THURSDAY THROUGH NEXT TUESDAY)
LOW AND MID LEVEL FLOW GRADUALLY BECOME MORE UPSLOPE DURING THE
DAY THURSDAY AS SURFACE HIGH PRESSURE BUILDS INTO THE PLAINS BY
AFTERNOON. AREA WILL ALSO SEE INCREASING UPWARD MOTION AHEAD OF
MAIN UPPER TROUGH MOVING INTO WRN COLORADO BY THU EVENING. EXPECT
-SHRA/-SHSN TO INCREASE THROUGH THE DAY OVER THE CENTRAL MOUNTAINS
AND ACROSS THE EASTERN MOUNTAINS/PALMER DIVIDE AS UPSLOPE DEEPENS
AND LIFT INCREASES. MAX TEMPS WILL BE COLD AREA-WIDE...THOUGH
AGAIN MAV GUIDANCE LOOKS TOO COLD FOR KCOS AND KPUB. BEST WINDOW
FOR PRECIP DEVELOPS THU NIGHT AS UPPER TROUGH MOVES
ACROSS...THOUGH WEAK SURFACE/MID LEVEL UPSLOPE WILL TEMPER SNOW
AMOUNTS SOMEWHAT. STILL APPEARS BEST BET FOR ACCUMULATING SNOW
WILL BE OVER TELLER COUNTY AND ACROSS THE PALMER DIVIDE...WHERE A
FEW SPOTS COULD SEE 6 PLUS INCHES BY MIDDAY FRI. MAY NEED A WINTER
WEATHER ADVISORY HERE EVENTUALLY...THOUGH WARM GROUND MAY LIMIT
SNOW ACCUMS SOMEWHAT. REMAINDER OF THE EASTERN MOUNTAINS AND I-25
CORRIDOR WILL LIKELY SEE AT LEAST A BRIEF PERIOD OF SNOW AND SOME
LIGHT ACCUMS...WHILE PLAINS SEE ONLY SPOTTY SNOW SHOWERS WITH
LITTLE OR NO ACCUMULATION. SNOW SHOULD DIMINISH FAIRLY QUICKLY
FRIDAY AS UPPER TROUGH IS WELL EAST OF THE STATE BY MIDDAY...AND
EXPECT ONLY FLURRIES/LIGHT -SHSN BY AFTERNOON. MAX TEMPS WILL
CONTINUE ON THE COLD SIDE WITH MANY AREAS STAYING WITHIN A FEW
DEGREES OF FREEZING.
ONCE UPPER SYSTEM EXITS THE AREA FRIDAY...WEATHER BECOMES VERY
QUIET AS UPPER LEVEL RIDGE BUILDS OVER THE WEEKEND BEFORE GIVING
WAY TO WARMER WESTERLY FLOW EARLY NEXT WEEK. TEMPS WILL REMAIN
BELOW NORMAL BOTH SATURDAY AND SUNDAY AS LOW/MID LEVELS WARM ONLY
SLOWLY UNDER WEAK FLOW ALOFT. MORE SUBSTANTIAL WARMING DEVELOPS
EARLY NEXT WEEK AS WESTERLY FLOW DEVELOPS AND PUSHES WARMER AIR
BACK INTO THE STATE.
AVIATION...WEAK FRONT MOVED ACROSS THE EASTERN PLAINS OVERNIGHT
WITH NORTH WINDS TO PERSIST BEHIND SYSTEM THROUGH THE MORNING.
GUSTY SOUTH TO SOUTHWEST WINDS TO REDEVELOP AT COS AND ALS LATE
THIS MORNING AND PERSISTING THROUGH THE EARLY EVENING. SW WINDS AT
PUB LIKELY TO REDEVELOP THROUGH THE EARLY AFTERNOON AS THIS
MORNINGS FRONT SLOWLY LIFTING BACK NORTH AND EAST ACROSS THE
PLAINS. STRONGER COLD FRONT TO MOVE ACROSS THE PLAINS THIS EVENING
WITH GUSTY NORTH WINDS AND MVFR AND LOCAL IFR CIGS DEVELOPING
BEHIND FRONT. FRONT LOOKS TO HIT THE PALMER DVD AND COS BETWEEN
03Z AND 06Z AND CONTINUING ACROSS THE REST OF THE EASTERN PLAINS
THROUGH THE EARLY MORNING. COULD SEE SOME LIGHT SNOW DEVELOPING AT
COS AFT 06Z. -MW
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ074-075-087-
088.
RED FLAG WARNING UNTIL 7 PM MDT THIS EVENING FOR COZ222-225-
228>230-232-233-237.
&&
$$
88/50
AREA FORECAST DISCUSSION...UPDATED
NWS PUEBLO CO
736 AM MDT WED OCT 24 2012
.UPDATE...
UPDATED TO CANCEL HIGH WIND WARNING FOR THE WET MTS THOUGH HAVE
KEPT FOR THE SOUTHERN SANGRE DE CRISTO MTS AND IMMEDIATE ADJACENT
TERRAIN ACROSS THE SOUTHERN I-25 CORRIDOR WITH OBS STILL
INDICATING WINDS GUSTING TO 50-60 MPH AND MODELS INDICATING H7
WINDS OF 50 KTS SLOWLY DIMININISHING THROUGH 16Z. FRONT HAS MADE
IT TO THE NEW MEXICO BORDER WITH LATEST HRRR INDICATING FRONT
LIFTING BACK NORTH AND EAST SOUTH OF THE ARKANSAS RIVER THROUGH
THE LATE AFTERNOON WITH SFC LOW DEVELOPING ACROSS EASTERN LAS
ANIMAS COUNTY. THIS WOULD ALLOW FOR GUSTY SOUTHWEST WINDS AND
CRITCIAL FIRE WEATHER CONDITIONS TO REDEVELOP ACROSS THE
SOUTHEASTERN MTS AND IMMEDIATE ADJACENT PLAINS LATER THIS
MORNING AND PERSISTING THROUGH THE EARLY EVENING. WILL LEAVE
CURRENT RED FLAG WARNING INTACT...HOWEVER...IF CURRENT MODELS
ARE CORRECT...MAY NOT SEE CRITICAL CONDITIONS ACROSS OTERO COUNTY
AND EASTERN PORTIONS OF PUEBLO COUNTY.
&&
.PREV DISCUSSION... /ISSUED 529 AM MDT WED OCT 24 2012/
SHORT TERM...
(TODAY AND TONIGHT)
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS CONTINUES TO
INDICATE MODERATE TO STRONG SOUTHWEST FLOW ALOFT ACROSS THE REGION
WITH BROAD UPPER TROUGH ACROSS THE WEST COAST AND GREAT BASIN. WATER
VAPOR IMAGERY ALSO INDICATING ONE EMBEDDED SHORT WAVE LIFTING OUT
ACROSS THE NORTHERN ROCKIES WITH ANOTHER WAVE TRANSLATING ACROSS THE
WEST COAST AND INTO THE GREAT BASIN. AT THE SURFACE...A WEAK FRONT
MOVED ACROSS THE EASTERN PLAINS THROUGH THE OVERNIGHT HOURS AND IS
CURRENTLY JUST NORTH OF A TRINIDAD TO SPRINGFIELD LINE. BRIEF GUSTY
NORTH WINDS HAVE BEEN NOTED BEHIND THE FRONT ALONG WITH INCREASING
LOW LEVEL MOISTURE...WITH RED CREEK RAWS INDICATING THE GUSTY
SOUTHWEST WINDS OF UP TO 60 MPH LAST EVENING BECOMING MORE EASTERLY
AND HAVE WEAKENED OVER THE PAST 2 HOURS. SW WINDS 20 TO 30 MPH WITH
GUSTS TO 60 MPH HAVE PERSISTED ACROSS THE HIGHER TERRAIN OF THE
SOUTHERN MTS WITH KPUX RADAR STILL INDICATING A HIGH WIND SIGNATURE
THROUGH THE OVERNIGHT HOURS.
TODAY...00Z MODELS HAVING A HARD TIME WITH THIS FRONT BUT 06Z AND
HIGHER RES MODELS INDICATING FRONT STALLING ACROSS THE COLORADO AND
NEW MEXICO BORDER LATER THIS MORNING AND THEN SLOWLY LIFTING BACK
NORTH AND EAST WITH A DEVELOPING SFC LOW ACROSS THE EASTERN PLAINS
AHEAD SHORT WAVE TRANSLATING ACROSS THE GREAT BASIN. SOUNDINGS STILL
INDICATING THE POTENTIAL FOR STRONG DOWNSLOPE FLOW WITH MT WAVE
ACROSS THE SOUTHERN MTS THROUGH THE EARLY MORNING AND HAVE KEPT HIGH
WIND WARNING IN PLACE THROUGH 9AM ACROSS THE WET MTS...THE SOUTHERN
SANGRE DE CRISTO MTS AND IMMEDIATE ADJACENT PLAINS OF THE SOUTHERN
I-25 CORRIDOR AND HAVE CANCELED FOR NORTHERN PORTIONS. EXPECTING
GUSTY SOUTHWEST WINDS TO REDEVELOP ACROSS ALL OF THE HIGHER
TERRAIN AND IMMEDIATE ADJACENT PLAINS THROUGH THE LATE MORNING AND
AFTERNOON WITH CRITICAL FIRE WEATHER CONDITIONS EXPECTED ONCE
AGAIN ACROSS THE SOUTHERN MTS AND SOUTHERN TIER ZONES ALONG THE
EASTERN NEW MEXICO BORDER AND HAVE KEPT CURRENT RED FLAG WARNING
IN PLACE FROM NOON TIL 7PM FOR THESE AREAS. HAVE CANCELED THE RED
FLAG WARNING FOR BENT...PROWERS AND CROWLEY COUNTIES WITH THE
INCREASED LOW LEVEL MOISTURE AND UPSLOPE FLOW EXPECTED TO DEVELOP
BEHIND THE FRONT. INCREASING MOISTURE AND LIFT AHEAD OF GREAT
BASIN SHORT WAVE AND ASSOCIATED FRONT WILL ALLOW FOR SCATTERED
SHOWERS TO DEVELOP ACROSS THE HIGHER TERRAIN OF THE CENTRAL MTS
THIS AFTERNOON.
TONIGHT...SHORT WAVE AND ASSOCIATED FRONT MARCHES ACROSS THE STATE
THIS EVENING WITH FRONT EXPECTED TO HIT THE PALMER DVD BETWEEN 00Z
AND 03Z WHICH CONTINUES ACROSS THE REST OF THE SOUTHEAST PLAINS
THROUGH EARLY THURSDAY MORNING. GUSTY NORTH WINDS OF 20-40 MPH AND
MUCH COOLER AIR TO BE USHERED INTO THE AREA BEHIND FRONT ALONG WITH
SOME GENERALLY LIGHT SNOWFALL...MAINLY TO THE HIGHER TERRAIN OF THE
PIKES PEAK REGION. -MW
LONG TERM...
(THURSDAY THROUGH NEXT TUESDAY)
LOW AND MID LEVEL FLOW GRADUALLY BECOME MORE UPSLOPE DURING THE
DAY THURSDAY AS SURFACE HIGH PRESSURE BUILDS INTO THE PLAINS BY
AFTERNOON. AREA WILL ALSO SEE INCREASING UPWARD MOTION AHEAD OF
MAIN UPPER TROUGH MOVING INTO WRN COLORADO BY THU EVENING. EXPECT
-SHRA/-SHSN TO INCREASE THROUGH THE DAY OVER THE CENTRAL MOUNTAINS
AND ACROSS THE EASTERN MOUNTAINS/PALMER DIVIDE AS UPSLOPE DEEPENS
AND LIFT INCREASES. MAX TEMPS WILL BE COLD AREA-WIDE...THOUGH
AGAIN MAV GUIDANCE LOOKS TOO COLD FOR KCOS AND KPUB. BEST WINDOW
FOR PRECIP DEVELOPS THU NIGHT AS UPPER TROUGH MOVES
ACROSS...THOUGH WEAK SURFACE/MID LEVEL UPSLOPE WILL TEMPER SNOW
AMOUNTS SOMEWHAT. STILL APPEARS BEST BET FOR ACCUMULATING SNOW
WILL BE OVER TELLER COUNTY AND ACROSS THE PALMER DIVIDE...WHERE A
FEW SPOTS COULD SEE 6 PLUS INCHES BY MIDDAY FRI. MAY NEED A WINTER
WEATHER ADVISORY HERE EVENTUALLY...THOUGH WARM GROUND MAY LIMIT
SNOW ACCUMS SOMEWHAT. REMAINDER OF THE EASTERN MOUNTAINS AND I-25
CORRIDOR WILL LIKELY SEE AT LEAST A BRIEF PERIOD OF SNOW AND SOME
LIGHT ACCUMS...WHILE PLAINS SEE ONLY SPOTTY SNOW SHOWERS WITH
LITTLE OR NO ACCUMULATION. SNOW SHOULD DIMINISH FAIRLY QUICKLY
FRIDAY AS UPPER TROUGH IS WELL EAST OF THE STATE BY MIDDAY...AND
EXPECT ONLY FLURRIES/LIGHT -SHSN BY AFTERNOON. MAX TEMPS WILL
CONTINUE ON THE COLD SIDE WITH MANY AREAS STAYING WITHIN A FEW
DEGREES OF FREEZING.
ONCE UPPER SYSTEM EXITS THE AREA FRIDAY...WEATHER BECOMES VERY
QUIET AS UPPER LEVEL RIDGE BUILDS OVER THE WEEKEND BEFORE GIVING
WAY TO WARMER WESTERLY FLOW EARLY NEXT WEEK. TEMPS WILL REMAIN
BELOW NORMAL BOTH SATURDAY AND SUNDAY AS LOW/MID LEVELS WARM ONLY
SLOWLY UNDER WEAK FLOW ALOFT. MORE SUBSTANTIAL WARMING DEVELOPS
EARLY NEXT WEEK AS WESTERLY FLOW DEVELOPS AND PUSHES WARMER AIR
BACK INTO THE STATE.
AVIATION...WEAK FRONT MOVED ACROSS THE EASTERN PLAINS OVERNIGHT
WITH NORTH WINDS TO PERSIST BEHIND SYSTEM THROUGH THE MORNING.
GUSTY SOUTH TO SOUTHWEST WINDS TO REDEVELOP AT COS AND ALS LATE
THIS MORNING AND PERSISTING THROUGH THE EARLY EVENING. SW WINDS AT
PUB LIKELY TO REDEVELOP THROUGH THE EARLY AFTERNOON AS THIS
MORNINGS FRONT SLOWLY LIFTING BACK NORTH AND EAST ACROSS THE
PLAINS. STRONGER COLD FRONT TO MOVE ACROSS THE PLAINS THIS EVENING
WITH GUSTY NORTH WINDS AND MVFR AND LOCAL IFR CIGS DEVELOPING
BEHIND FRONT. FRONT LOOKS TO HIT THE PALMER DVD AND COS BETWEEN
03Z AND 06Z AND CONTINUING ACROSS THE REST OF THE EASTERN PLAINS
THROUGH THE EARLY MORNING. COULD SEE SOME LIGHT SNOW DEVELOPING AT
COS AFT 06Z. -MW
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 9 AM MDT THIS MORNING FOR COZ074-075-087-
088.
RED FLAG WARNING FROM NOON TODAY TO 7 PM MDT THIS EVENING FOR
COZ222-225-228>230-232-233-237.
&&
$$
23/23
AREA FORECAST DISCUSSION
NWS NEW YORK NY
213 AM EDT WED OCT 24 2012
.SYNOPSIS...
A STATIONARY FRONT WILL REMAIN JUST SOUTH OF LONG ISLAND INTO
WEDNESDAY AS A LOW PRESSURE WAVE SLIDES TO THE SOUTH. HIGH
PRESSURE THEN NOSES DOWN FROM THE NORTH WEDNESDAY NIGHT. THE HIGH
WILL WORK SLOWLY EASTWARD THROUGH THE UPCOMING WEEKEND...WHILE A
COLD FRONT APPROACHES FROM THE WEST.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
FOR THE REST OF THE OVERNIGHT PERIOD...STILL HAVE SOME WIDELY
SCATTERED SHOWERS WITH LIGHT NE WINDS. A STATIONARY FRONT IS
OVERLAID ACROSS THE REGION. FROM CURRENT DOPPLER RADAR REFLECTIVITY
FIELDS...SHOWER ACTIVITY IS LOWERING IN COVERAGE WITH TIME AND THIS
TREND IS REFLECTED WITHIN THE LAST FEW RUNS OF THE HRRR MODEL AS
WELL.
HOWEVER...DID NOT LOWER POPS TOO MUCH TOWARDS EARLY WEDNESDAY
MORNING WITH AN EMBEDDED SHORTWAVE ALONG THE NW FLOW ALOFT MOVING
CLOSER TO THE REGION. THE ASSOCIATED POSITIVE VORTICITY ADVECTION
WITH REMAINING LOW LEVEL MOISTURE SHOULD PROVIDE SOME FORCING FOR
MORE SHOWERS TO DEVELOP. THE MODELS SEEMS TO HAVE MUCH OF THIS
TOWARDS THE NORTHERN AND EASTERN PORTIONS OF THE CWA.
OTHERWISE...MIN TEMPS SLIGHTLY ADJUSTED FROM RECENT OBSERVATIONS AND
STILL EXPECTED TO BE CLOSE TO 10 DEGREES ABOVE CLIMATOLOGICAL NORMAL
LOWS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/...
FOR WEDNESDAY...LOOKING FOR THE FRONTAL BOUNDARY TO STAY WITHIN THE
REGION. IN THE MORNING...BEHIND THE SHORTWAVE ALOFT...POSITIVE
VORTICITY ADVECTION WILL BE LOWERING AND LOW LEVEL MOISTURE WILL
REMAIN ABUNDANT. HOWEVER...NOTED THAT SOME DRIER AIR WILL BE
STARTING TO MOVE IN ALOFT...GENERALLY ABOVE 700MB ON AVERAGE. THIS
SHOULD LOWER THE AMOUNT OF COLLISION COALESCENCE...RESULTING IN A
TRANSITION TO DRIZZLE. THE FLOW WILL BE MOSTLY NORTHEASTERLY TO
EASTERLY AROUND 5 TO 10 MPH.
THERE IS A PRETTY DECENT INVERSION FROM 950 TO 900 MB TOO...WHICH
SHOULD HELP TRAP THE LOW LEVEL MOISTURE AND KEEP DRIZZLE IN PLACE.
RAIN AMOUNTS LIKEWISE ARE VERY SMALL AND ON THE ORDER OF A FEW
HUNDREDTHS OF AN INCH.
TEMPERATURES WERE TAKEN FROM A BLEND OF THE NAM12 AND MET GUIDANCE
WHICH LEANS TOWARDS THE COOLER SIDE OF THE GUIDANCE. HIGH TEMPS
MOSTLY AROUND NORMAL LEVELS FOR MOST LOCATIONS.
UPPER RIDGING GRADUALLY BUILDS IN FROM THE WEST WED NIGHT...WHILE
SURFACE HIGH PRESSURE CONTINUES TO NOSE DOWN FROM QUEBEC.
CONTINUED ONSHORE FLOW UNDER A STRONG SUBSIDENCE INVERSION WILL
LIKELY MAINTAIN STRATUS OVER MUCH OF THE REGION. BASED ON LOW
LEVEL MOISTURE PROFILES...NE ZONES COULD HAVE A CHANCE OF SEEING
SOME CLEARING LATE...BUT CONFIDENCE NOT HIGH. ONCE AGAIN UPSLOPE
FLOW WILL BRING INCREASING CHANCES FOR DRIZZLE ACROSS
WESTERN/INTERIOR SECTIONS. TEMPS WILL REMAIN ABOVE SEASONABLE WED
NIGHT IN ONSHORE FLOW AND CLOUD COVER...GENERALLY LOWER/MID 50S
CITY/COAST AND MID TO UPPER 40S INTERIOR.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
FORECAST COMPLEXITIES ARISE EARLY NEXT WEEK...SPECIFICALLY WITH THE
HANDLING OF THE POST-TROPICAL PHASE OF TROPICAL STORM SANDY EARLY
NEXT WEEK. NHC FORECASTS SANDY TO MOVE NEARLY DUE NORTH TOWARD THE
BAHAMAS THROUGH FRI MORNING AND THEN NORTHEAST THEREAFTER...BECOMING
A POST-TROPICAL CYCLONE UPON REACHING 31N 70.5W BY SUNDAY MORNING.
ITS INTERACTION WITH A DEVELOPING OMEGA BLOCK CONSISTING OF A
BLOCKING UPPER HIGH OVER THE NORTH ATLANTIC...AN OCEAN STORM OVER
THE CENTRAL NORTH ATLANTIC...AND A DIGGING...NEGATIVELY TILTED UPPER
TROUGH FROM THE NORTHERN PLAINS TO THE OHIO VALLEY...IS CRITICAL IN
DETERMINING THE FUTURE EVOLUTION OF THIS STORM. THERE COULD STILL BE
A WINDOW OF OPPORTUNITY FOR THE STORM TO UNDERCUT THE BLOCK AND HEAD
EAST INTO THE OPEN ATLANTIC PER THE OPERATIONAL GFS...SOME GFS
ENSEMBLE MEMBERS AND THE GLOBAL GEM...BUT AT THE SAME TIME A GROWING
NUMBER OF GFS ENSEMBLE MEMBERS ARE SIDING WITH THE MORE CONSISTENT
ECMWF SOLUTION OF TAKING THE STORM NORTHWARD ALONG 70W
THEREAFTER...AND MAKING A NW TURN BACK TOWARD THE EAST COAST BY
MON-TUE AS THE STORM PHASES WITH AND/OR UNDERGOES FUJIWARA
INTERACTION WITH THE DIGGING UPPER TROUGH...AND AS THE DOWNSTREAM
BLOCKING HIGH OFFERS LITTLE CHANCE OF AN OUT-TO-SEA PATH. WHERE AND
WHEN ANY SUCH NW TURN OF THE STORM WOULD TAKE PLACE...AND AT WHAT
INTENSITY...ARE HIGHLY UNCERTAIN...AS THE ECMWF COULD BE TOO PHASED/
AMPLIFIED AND TOO FAR WEST...AND AS THE NW-BENDING GFS ENSEMBLE
MEMBERS DISAGREE ON THE POINT OF ANY NW RE-CURVATURE...OCCURRING
ANYWHERE FROM 55W TO 70W. FORECAST DETAILS NECESSARILY REMAIN
SKETCHY AT THIS POINT. WINDY CONDITIONS...HEAVY RAIN AND SOME COASTAL
FLOODING COULD EVENTUALLY BECOME LIKELY...WITH A WORST CASE
SCENARIO OF FLOODING RAINS...DAMAGING WINDS...AND SIGNIFICANT
COASTAL FLOODING...FOR PARTS OF THE AREA. STAY TUNED.
PRIOR TO THIS TIME...THE REGION WILL BE UNDER A DOME OF HIGH
PRESSURE ALOFT AND A SURFACE HIGH ALONG THE NEW ENGLAND COAST.
THIS WILL GENERALLY SPELL A CONTINUATION OF ONSHORE FLOW AND A
SLIGHT CHANCE OF LIGHT RAIN/DRIZZLE THU INTO EARLY FRI MORNING...
VIA RESIDUAL MOISTURE TRAPPED BENEATH A STRENGTHENING LOW LEVEL
INVERSION AND THE CLOSE PROXIMITY OF A DISSIPATING FRONTAL BOUNDARY.
TEMPS ON FRI COULD RISE WELL INTO THE 70S FROM NYC NORTH/WEST IF LOW
LEVEL FLOW IS MORE SW THAN S...BUT EXPECT COOLER CONDITIONS ON SAT
DESPITE SUNSHINE AS FLOW AGAIN TURNS ONSHORE.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
A STATIONARY FRONT REMAINS SOUTH OF LONG ISLAND INTO TONIGHT.
AFTER A VFR START...EXPECT CONDITIONS TO VARY FROM VFR AND MVFR
TOWARDS SUNRISE...THEN BECOME MAINLY MVFR THIS MORNING AND
AFTERNOON WITH AREAS OF DRIZZLE. CONFIDENCE IN MVFR IS
MODERATE...WITH A CHANCE THAT IT COULD REMAIN MAINLY VFR. MAINLY
VFR WITH POSSIBLY POCKETS OF MVFR THIS EVENING...AS POTENTIAL FOR
DRIZZLE WANES. EXCEPTION TO THIS KSWF WHICH STARTS OUT
LIFR...IMPROVING TO MVFR AROUND MID MORNING. SHOULD SEE AREA OF
DRIZZLE AT KSWF THROUGHOUT THE TAF PERIOD.
.OUTLOOK FOR 06Z THURSDAY THROUGH SUNDAY...
.LATE WEDNESDAY NIGHT...VARIABLE CIGS RANGING FROM MVFR TO VFR.
.THURSDAY...GRADUAL IMPROVEMENT TO VFR.
.THURSDAY NIGHT...MVFR POSSIBLE.
.FRIDAY-SATURDAY...VFR.
.SUNDAY...SUB-VFR CONDITIONS AND GUSTY NE WINDS POSSIBLE.
&&
.MARINE...
SUB-ADVISORY CONDITIONS EXPECTED THROUGH WED NIGHT. A WEAK LOW
PRESSURE WAVE WILL PASS SOUTH OF THE REGION TONIGHT INTO
WEDNESDAY...WITH HIGH PRESSURE BUILDING IN FROM THE NORTH WED
NIGHT.
QUIET CONDITIONS WILL BE IN PLACE THU THROUGH SAT WITH A DISSIPATING
FRONTAL BOUNDARY THU INTO THU NIGHT...FOLLOWED BY HIGH PRESSURE
BUILDING IN FROM OFF THE NEW ENGLAND COAST.
OCEAN SEAS COULD BEGIN TO REACH SCA CONDITIONS AS EARLY AS SAT
AFTERNOON OR NIGHT VIA SWELLS FROM TROPICAL STORM SANDY. A
STRENGTHENING EASTERLY FLOW SHOULD DEVELOP ON SUNDAY AS SANDY
BECOMES POST-TROPICAL AND BEGINS INTERACTING WITH HIGH PRESSURE TO
THE NORTH...WITH GUSTS UP TO 25 KT POSSIBLE ON THE OCEAN AND THE
EASTERN SOUND/BAYS.
WAVEWATCH SEAS GENERALLY ACCEPTED...EXCEPT MAINTAINED A BUILDING
TREND FOR OCEAN SEAS INTO SUNDAY...AS HIGH AS 10 FT SUNDAY MORNING
AND AS HIGH AS 15 FT BY MON MORNING.
&&
.HYDROLOGY...
NO SIGNIFICANT RAIN IS EXPECTED THROUGH THE WEEK...WITH A BASIN
AVERAGE OF AROUND A TENTH OF AN INCH OR LESS EXPECTED THROUGH
WEDNESDAY.
THEN POTENTIAL FOR VERY HEAVY RAIN EXISTS FOR EARLY NEXT
WEEK...EITHER DIRECTLY FROM SANDY OR FROM INFLUX OF ATLANTIC
MOISTURE ON A STRENGTHENING DEEP LAYER EASTERLY FLOW...AND LIFT
VIA AN APPROACHING COLD FRONT AND/OR AN INVERTED LOW PRESSURE
TROUGH EXTENDING WELL TO THE NORTH OF SANDY.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...NV
NEAR TERM...JM
SHORT TERM...JM/NV
LONG TERM...GOODMAN
AVIATION...MALOIT
MARINE...NV/GOODMAN
HYDROLOGY...NV/GOODMAN
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
638 AM EDT WED OCT 24 2012
.SYNOPSIS...
A FRONTAL BOUNDARY DRAPED ACROSS THE REGION WILL GRADUALLY PROGRESS
SOUTHWARD THROUGH TODAY. HIGH PRESSURE FROM SOUTHEASTERN CANADA AND
NORTHERN NEW ENGLAND WILL SPREAD SOUTH ALONG THE EASTERN SEABOARD
DURING THURSDAY AND FRIDAY. OVER THE WEEKEND, A COLD FRONT IS
FORECAST TO APPROACH THE REGION FROM THE WEST ON SATURDAY AS A
TROPICAL SYSTEM ADVANCES NORTH IN THE ATLANTIC FROM THE CARIBBEAN.
UNCERTAINTY REMAINS WITH THE TRACK OF THIS TROPICAL SYSTEM. PLEASE
REFERENCE THE LATEST INFORMATION FROM THE NATIONAL HURRICANE CENTER.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE NEXT MID LEVEL SHORT WAVE IS TAKING ADVANTAGE OF THE MOISTURE
IN PLACE ACROSS NORTH CENTRAL PENNSYLVANIA AND SPARKING UP SHOWERS
AHEAD OF IT. EXTRAPOLATION PLACES THIS FEATURE EAST OF THE AREA
AROUND 1500 UTC. BASED ON THE RADAR COVERAGE AND THE TIMING
MENTIONED ABOVE...THE SHOWER CHANCES WERE INCREASED ACROSS ROUGHLY
THE NORTHERN THIRD OF THE AREA. THE TIMING AND COVERAGE IS MORE OR
LESS IN LINE WITH THE LATEST HRRR OUTPUT...WHICH SEEMS TO HAVE A
GOOD HANDLE ON THE SITUATION.
THE FOG HAS EASED ACROSS SOUTHEAST AND SOUTH CENTRAL PENNSYLVANIA
AS THE MID CLOUDS CUT OFF THE RADIATIONAL COOLING AT THE TOP OF
THE MOIST BOUNDARY LAYER. A MENTION OF PATCHY FOG WAS LEFT IN
PLACE FOR MOST AREAS THIS MORNING TO ACCOUNT FOR THE PATCHY FOG IN
PLACE NOW.
SINCE THERE IS SOME MOISTURE LEFT IN THE GREAT LAKES LINK (PRECIPITABLE
WATER VALUES ARE NEAR 1.30 INCHES IN THE SOURCE OF THE MOISTURE)...
SCATTERED SHOWERS ARE POSSIBLE MOST OF THE DAY ACROSS NORTHERN
AREAS. FURTHER SOUTH...THE FOCUS FOR PRECIPITATION BECOMES MORE
NEBULOUS...AND A SLIGHT CHANCE OF SHOWERS MAY NEED TO BE CARRIED
THROUGH THE DELAWARE VALLEY.
SHORT MODELS ARE SHOWING SOME INSTABILITY IN THE VICINITY OF THE
FRONT (WHICH SHOULD STRETCH FROM DELAWARE THROUGH CENTRAL
PENNSYLVANIA DURING THE MID TO LATE AFTERNOON). MODIFIED MODEL
SOUNDINGS IN THIS AREA SHOW THAT THE INSTABILITY IS SHALLOW AT
BEST...AND FOR SOUTHERNMOST AREAS THE FORECAST WILL REMAIN DRY FOR
TODAY.
IT REMAINS TO BE SEEN JUST HOW MUCH LOW CLOUDINESS CAN FORM ACROSS
NORTHERN AREAS EARLY THIS MORNING. IT IS NOT FAR AWAY...AS SURFACE
OBSERVATIONS AND THE GEOCAT IFR PROBABILITY PRODUCT SHOW STRATUS
STRETCHING ACROSS THE SOUTHERN POCONOS AND NORTHWEST NEW JERSEY. IN
THIS AREA...ANY SUNSHINE LOOKS DOUBTFUL...SO HIGH WERE BASED MAINLY
ON THE SLIGHTLY COOLER NAM MOS NUMBERS.
FURTHER SOUTH...ROUGHLY SOUTH OF A KRDG-KPHL-KMJX LINE...AND
ESPECIALLY SOUTH OF THAT LINE...SOME SUNSHINE THROUGH HIGH
CLOUDINESS IS POSSIBLE THIS AFTERNOON. 850 MB TEMPERATURES NEAR 12
CELSIUS COULD SUPPORT HIGHS IN THE UPPER 70S WITH FULL SUN. SINCE
FULL SUN LOOKS UNLIKELY...HIGHS CLOSER TO THE MOS BLEND LOOKS
OK...SINCE THE COLUMN IS WARM TO BEGIN WITH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
WHILE THERE COULD BE SOME SHOWERS ACROSS NORTHER AREAS AS WEAK SHORT
WAVE RIPPLE THROUGH THE RISING MID LEVEL FLOW...MOST PLACES SHOULD
BE RAIN FREE. THE MAIN FORECAST PROBLEM FOR TONIGHT SHOULD BE THE
EXPANSION OF LOW CLOUDS AND FOG.
NAM MODEL SOUNDINGS SUGGEST THAT THE STRATUS SHOULD FORM IN PLACE
DURING THE EVENING HOURS...AND SPREAD OUT TO JUST ABOUT ALL AREAS
(EXCEPT PERHAPS PORTIONS OF NORTHEAST MARYLAND AND SOUTHERN
DELAWARE. THE 0000 UTC GFS IS NOT AS BULLISH WITH RESPECT TO
TIMING...BUT EVENTUALLY SATURATES THE TOP OF THE INVERSION FOR
STRATUS. BASED ON THE ABOVE...ALL AREAS EXCEPT THE FAR SOUTH SHOULD
BECOME CLOUDY.
THE NEXT PROBLEM IS FOG AND DRIZZLE. A MOIST BOUNDARY LAYER WITH AN
EASTERLY FLOW SHOULD PROMOTE FOG DEVELOPMENT...ESPECIALLY IN THE
SOUTHERN POCONOS AND LEHIGH VALLEY...WHERE THE FLOW IS MODESTLY
UPSLOPE. ELSEWHERE...FOG DEVELOPMENT SHOULD OCCUR...BUT DENSITY IS
IN QUESTION. THE DEVELOPMENT OF STRATUS COULD MITIGATE THE POTENTIAL
TO COOL THE TOP OF THE INVERSION AND INDUCE DENSER FOG TO FORM.
FOR NOW...WILL INCLUDE THE MENTION OF FOG...BUT NOT HIT IT TOO HARD.
IT IS INTERESTING TO NOTE THAT...SYNOPTICALLY...HAVING HIGH PRESSURE
TO THE NORTHEAST IS A FAVORED PATTERN FOR DENSE FOG TO DEVELOP. THIS
POTENTIAL WILL NEED TO BE REASSESSED BY LATER SHIFTS.
THE LATER DEVELOPMENT OF THE LOW CLOUDS BY THE 0000 UTC GFS ALLOWS
FOR SOME RADIATIONAL COOLING...AND LOWER LOW TEMPERATURES. SINCE
STRATUS IS EXPECTED TO FORM BEFORE THE GFS TIMING...LOWS WERE BASED
MORE ON A MOS BLEND.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
TO START THE LONG TERM, SURFACE HIGH PRESSURE AND A MID-LEVEL RIDGE
WILL EXTEND FROM SOUTHEASTERN CANADA AND THE NEW ENGLAND STATES DOWN
ALONG THE MID-ATLANTIC TO SOUTHEASTERN SEABOARDS. WITH MAINLY LIGHT
EAST WINDS OFF OF THE ATLANTIC, A FAIR AMOUNT OF CLOUD COVER IS
EXPECTED BOTH DAYS ACROSS THE AREA. 850MB MODEL TEMPS STILL YIELD
MILD CONDITIONS ACROSS THE REGION THURSDAY AND FRIDAY, WITH HIGH
TEMPS RANGING FROM THE MID 60S NORTH TO THE LOWER 70S SOUTH. WITH
THE LIGHT EAST FLOW, THE GFS AND EURO HINT AT THE POSSIBILITY OF
LIGHT PRECIP/DRIZZLE, ESPECIALLY THURSDAY NIGHT TO EARLY MORNING
FRIDAY, AND SLIGHT CHANCE POPS HAVE BEEN RETAINED. SKY COVER WAS
INCREASED IN THIS TIMEFRAME AS MODEL SOUNDINGS POINT TOWARD
INCREASING LOW CLOUDS.
GOING INTO THE WEEKEND AND EARLY NEXT WEEK, MUCH UNCERTAINTY REMAINS
WITH REGARDS TO THE TIMING OF AN APPROACHING COLD FRONT FROM THE
WEST AND ALSO THE TRACK OF TROPICAL SYSTEM SANDY. THE ECMWF
CONTINUES TO HAVE THE MOST WESTWARD TRACK OF SANDY, BUT SOME GFS
ENSEMBLE MEMBERS ARE ALSO SHOWING A SIMILAR SOLUTION. STILL, OTHER
MODEL DATA RECURVES SANDY MORE SHARPLY AND TAKES THE SYSTEM MORE
EAST AND OUT TO SEA. IN COLLABORATING WITH NEIGHBORING OFFICES AND
WITH THIS MUCH UNCERTAINTY AT THIS LONG RANGE PERIOD, WE HAVE MADE
SMALL CHANGES TO THE END OF THE EXTENDED FCST. AS MODEL SOLUTIONS
COME TO CLOSER AGREEMENT, ADDITIONAL ADJUSTMENTS CAN BE MADE TO THIS
TIMEFRAME. FOR NOW, THE INTERACTION OF THE SLOW MOVING COLD FRONT
AND THE TROPICAL OR POST-TROPICAL SYSTEM HAS THE POTENTIAL TO
PRODUCE HIGH WINDS, HEAVY RAIN, RIVER/STREAM FLOODING, AND COASTAL
FLOODING. AS THIS IS A POTENTIALLY HIGH IMPACT EVENT, WE WILL
CONTINUE TO HIGHLIGHT THIS SYSTEM IN OUR HAZARDOUS WEATHER OUTLOOK.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
VFR CONDITIONS CONTINUE EARLY THIS MORNING. THE EXCEPTION IS
KTTN...WHICH NOW HAS AN IFR CEILING. THE EXTENT OF THE STRATUS IS
BEING PORTRAYED WELL BY SATELLITE. AT THIS POINT...IT APPEARS AS
THOUGH KTTN WILL BE THE ONLY TERMINAL SITE THAT WILL BE AFFECT BY
THE STRATUS. AS IT STANDS NOW...THE STRATUS LOOKS TO LIFT AS THE
BOUNDARY LAYER MOISTURE EASES BEFORE 1500 UTC.
OTHERWISE...THE KPHL METRO AIRPORTS SHOULD HAVE A MAINLY VFR FORECAST
THROUGH 1400 UTC...WITH A DECK NEAR 1000 FEET AS AN INDICATOR OF
POSSIBLY LOWER CONDITIONS. IF THE LOWER CLOUDS ACROSS EAST CENTRAL
NEW JERSEY EXPAND...IFR CONDITIONS ARE POSSIBLE AFTER 1000 UTC.
LOWER CLOUDS (IF THEY FORM) SHOULD TEND TO BREAK AFTER 1400-1500
UTC...AND MAINLY VFR CONDITIONS ARE EXPECTED FOR THE REMAINDER OF
THE MORNING. LOWER CLOUDS MAY LINGER NEAR KACY DURING THE
AFTERNOON...AND COME BACK ACROSS THE REGION TONIGHT. SOME OF THE
STATISTICAL GUIDANCE IS SHOWING IFR CONDITIONS RETURNING AFTER
0100 UTC THURSDAY. SINCE LOWER CLOUDS ARE PRESENT...IFR CONDITIONS
ARE FORECAST AFTER THIS TIME FOR MOST PLACES FOR TONIGHT.
OUTLOOK...
THURSDAY...MVFR CONDITIONS IN LOWER CLDS TO START THE DAY, THEN
EXPECTED IMPROVEMENT TO VFR BY AFTERNOON.
FRIDAY...MAINLY VFR. HOWEVER, A MAINLY EASTERLY FLOW COULD RESULT IN
MVFR CONDITIONS AND POSSIBLE FOG IN THE FIRST PART OF THE DAY.
SATURDAY...FOR MUCH OF THE DAY, VFR CONDITIONS. HOWEVER, CONFIDENCE
IS BELOW AVERAGE AS THERE IS MUCH MODEL SPREAD ON THE TIMING AND
PLACEMENT OF UPCOMING WEATHER SYSTEMS.
SUNDAY...MVFR CONDITIONS WITH AREAS OF RAIN POSSIBLE.
&&
.MARINE...
A WEAK SURFACE FRONT DROPPING SOUTH ACROSS THE WATER THIS MORNING
WILL EITHER CONTINUE TO DROP SOUTH OF THE AREA...OR PERHAPS EVEN
DISSIPATE. THE NET EFFECT OF THE FRONTAL PASSAGE WILL BE A WIND
DIRECTION SHIFT...WITH ONLY THE SOUTHERNMOST OCEAN WATERS NOT SEEING
THE SHIFT DURING THE DAY. AS HIGH PRESSURE BUILDS SOUTH FROM
QUEBEC...THE GRADIENT MAY TIGHTEN A BIT LATER THIS AFTERNOON AND
THIS EVENING. HOWEVER...WINDS SPEEDS AS ARE EXPECTED TO REMAIN BELOW
12 KNOTS TODAY.
AS THE HIGH BUILDS DOWN THE COAST FROM NORTHERN NEW ENGLAND...WINDS
WILL SNAP TO THE SYNOPTIC WIND DIRECTION (NORTH NORTHEAST). THE
GRADIENT COULD TIGHTEN ENOUGH LATE THIS EVENING TO ALLOW WINDS TO
INCREASE TO 10 TO 15 KNOTS ON THE OCEAN WATERS LATE TONIGHT.
HOWEVER...SEAS PROBABLY DO NOT HAVE TIME TO RESPOND TO THE
DEVELOPING FETCH...SO WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW
SMALL CRAFT LIMITS TONIGHT.
OUTLOOK...
OVERALL, GENERALLY QUIET CONDITIONS ARE EXPECTED FOR THE WATERS IN
THE THURSDAY TO FRIDAY TIMEFRAME WITH AN AREA OF HIGH PRESSURE
EXTENDING ALONG THE EASTERN SEABOARD. THUS, CONDITIONS ARE EXPECTED
TO BE SUB-SCA CRITERIA. MARINE FLAGS MAY BE NEEDED LATER IN THE
WEEKEND, HOWEVER, DEPENDING ON THE TRACK AND STRENGTH OF TROPICAL
SYSTEM SANDY AND ALSO A COLD FRONT APPROACHING FROM THE WEST. SEAS
WILL BE INCREASING LATE SATURDAY THROUGH SUNDAY WITH THE APPROACH OF
SANDY, AND A TIGHTENING GRADIENT WILL ALSO LEAD TO WINDS INCREASING
AS WELL.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KLINE
NEAR TERM...HAYES
SHORT TERM...HAYES
LONG TERM...KLINE
AVIATION...HAYES/KLINE
MARINE...HAYES/KLINE
AREA FORECAST DISCUSSION
NWS LINCOLN IL
851 PM CDT THU OCT 25 2012
.DISCUSSION...
ISSUED 845 PM CDT THU OCT 25 2012
THE STRONG COLD FRONT HAS PUSHED INTO SOUTHEAST ILLINOIS THIS
EVENING WITH TEMPERATURES DROPPING SOME 25 TO 30 DEGREES BEHIND
THE BOUNDARY. BAND OF RAIN AND ISOLATED CONVECTION CONTINUES TO
SLOWLY MARCH NORTHEAST BEHIND THE SHARP COLD FRONT IN ZONE OF
STRONG 850-700 MB FRONTOGENESIS. THIS STRONG LIFT IS FORECAST TO
SLOWLY LIFT OFF TO THE NORTH AND EAST LATE THIS EVENING TAKING THE
RAIN CHANCES WITH IT...EXCEPT FOR THE FAR EAST AND ESPECIALLY
SOUTHEAST AREAS WHERE THE FRONT WILL TEND TO SLOW DOWN SOME AS A
SECONDARY WAVE SHIFTS EAST ACRS THE PLAINS RESULTING IN RAIN
CHANCES CONTINUING THRU AT LEAST FRIDAY MORNING ACRS THE FAR
SOUTHEAST.
MODELS WERE CLUELESS WITH RESPECT TO THE MOISTURE/CLOUDS UP TO
OUR NORTHWEST WELL BEHIND THE COLD FRONT LATE TODAY AND THIS
EVENING. FORECAST SOUNDINGS FROM THE HIGH RES SHORT TERM MODELS
WERE STARTING TO TREND SLOWER WITH ANY CLEARING ACRS THE AREA
OVERNIGHT AND BASED ON WHAT I AM SEEING UPSTREAM ON SATELLITE
DATA...WE PROBABLY WON`T BE SEEING MUCH IN THE WAY OF CLEARING
AROUND HERE UNTIL LATER FRIDAY MORNING OR DURING THE AFTERNOON.
LOOKING AT UPSTREAM 00Z SOUNDING DATA SUGGESTS CLOUD LAYER
IN THE 2500-3500 FOOT RANGE WITH A FAIRLY DECENT INVERSION JUST
ABOVE THAT TO TRAP A LOT OF THE MOISTURE THAT WOULD HAVE NORMALLY
BEEN SWEPT OUT OF THE AREA WITH THE AMOUNT OF SUBSIDENCE NOTED
IN THE WAKE OF THE UPPER WAVE ACRS THE REGION. NOT SEEING ANY
EVIDENCE OF ANY BREAKS IN THE CLOUD COVER WITH THE CLOUDS EXTENDING
NW INTO SOUTHERN CANADA.
AS A RESULT...WILL HAVE TO MAKE SOME SIGNIFICANT CHANGES TO THE
CLOUD COVER OVER THE FORECAST AREA FOR THE OVERNIGHT HOURS AND
INTO FRIDAY MORNING...WITH CONFIDENCE ON ANY CLEARING LATE FRIDAY
MORNING NOT THAT HIGH AT THIS POINT EITHER. HAVE BUMPED LOWS UP
FOR TONIGHT A DEGREE OR TWO AND WE MAY NEED TO MAKE SOME ADJUSTMENTS
TO THE EXPECTED HIGH TEMPS ON FRIDAY IF CLOUDS HANG ON THRU THE
DAY. ZONE UPDATE SHOULD BE OUT BY 900 PM.
SMITH
&&
.AVIATION...
ISSUED 635 PM CDT THU OCT 25 2012
MAIN FORECAST CONCERN WILL BE WITH THE MVFR CIGS OVERNIGHT AND
HOW QUICKLY THEY WILL CLEAR OUT OF OUR AREA...IF AT ALL. THE
COLD FRONT HAS SHIFTED EAST OF CMI WITH AREAS SEEING GUSTY
NORTHWEST WINDS WHICH SHOULD CONTINUE THRU THE EVENING HOURS.
ONE MORE BAND OF RAIN WITH ISOLD THUNDER WILL PUSH ACRS THE
AREA OVER THE NEXT SEVERAL HOURS ACCOMPANIED BY OCCASIONAL
IFR CIGS WITH SOME OF THE HEAVIER DOWNPOURS. ONCE THIS LAST
BAND OF PRECIP CLEARS OUR AREA...WE WILL HAVE TO WAIT TO SEE
JUST WHAT HAPPENS WITH THE LARGE AREA OF MVFR CIGS OUT TO OUR
WEST WHICH MODELS HAVE NOT HANDLED VERY WELL. RAP FORECAST
SOUNDINGS SEEM TO BE THE ONLY MODEL SUGGESTING THE LOW LEVEL
MOISTURE WILL HANG AROUND OUR AREA A BIT LONGER THAN WHAT WAS
EARLIER THOUGHT...SO WILL TREND IN ITS DIRECTION THRU FRIDAY
MORNING. WILL GRADUALLY BRING CIGS UP BUT KEEP THEM IN THE MVFR
CAT INTO FRIDAY MORNING AND THEN SCATTER THEM OUT AT OR JUST AFTER
17Z. NORTHWEST TO NORTH WINDS WILL CONTINUE THRU THE DAY ON
FRIDAY AND MAY BECOME GUSTY AGAIN DURING THE AFTN...ESPECIALLY IF
WE CAN GET SOME SUNSHINE.
SMITH
&&
.PREV DISCUSSION...
ISSUED 258 PM CDT THU OCT 25 2012
SHORT TERM...TONIGHT THROUGH SUNDAY
19Z/2PM SURFACE ANALYSIS INDICATES STRONG COLD FRONT HAS PUSHED
EAST OF THE MISSISSIPPI RIVER...WITH WINDS TURNING NORTHWESTERLY
AT BOTH KMQB AND KGBG. LATEST SATELLITE/RADAR IMAGERY IS SHOWING
INCREASING COVERAGE OF POST-FRONTAL PRECIP ACROSS EASTERN IOWA AND
NORTHERN MISSOURI. AS FRONT MOVES FURTHER EAST...SHOWERS AND
THUNDERSTORMS WILL SPREAD INTO WEST-CENTRAL ILLINOIS OVER THE NEXT
COUPLE OF HOURS...THEN FURTHER EAST TOWARD THE INDIANA BORDER
BETWEEN 03Z AND 06Z. WILL CARRY CATEGORICAL POPS ACROSS THE BOARD
THIS EVENING...THEN WILL LINGER RAIN CHANCES ONLY ACROSS THE E/SE
KILX CWA AFTER MIDNIGHT. TOTAL RAINFALL WILL GENERALLY RANGE FROM
ONE QUARTER TO ONE HALF AN INCH...WITH ISOLATED HIGHER AMOUNTS
WITHIN STORMS. ONCE FRONT PASSES...MUCH COLDER AIRMASS WILL SPILL
INTO THE AREA ON GUSTY W/NW WINDS. WINDS MAY GUST AS HIGH AS 30 MPH
AT TIMES IMMEDIATELY BEHIND THE BOUNDARY BEFORE SLOWLY DIMINISHING
LATER. OVERNIGHT LOW TEMPERATURES WILL RANGE FROM THE MIDDLE 30S
ACROSS THE ILLINOIS RIVER VALLEY...TO THE UPPER 40S NEAR THE
INDIANA BORDER.
12Z OCT 25 MODELS ARE A BIT FASTER WITH FROPA THAN PREVIOUS
RUNS...WITH BOUNDARY WELL EAST INTO INDIANA BY 12Z FRI. AS A
RESULT...HAVE ONLY LINGERED CHANCE POPS FOR SHOWERS ACROSS THE FAR
E/SE CWA INTO FRIDAY MORNING...WITH DRY CONDITIONS EXPECTED ACROSS
THE BOARD BY AFTERNOON. MAIN STORY ON FRIDAY WILL BE THE MUCH
COOLER WEATHER...WITH HIGH TEMPS REMAINING IN THE LOWER TO MIDDLE
50S. AS HIGH PRESSURE BUILDS IN FROM THE WEST...WINDS WILL DIMINISH TO
LESS THAN 10 MPH FRIDAY NIGHT. GIVEN CLEAR SKIES AND LIGHT
WINDS...EXCELLENT RADIATIONAL COOLING CONDITIONS WILL ALLOW LOW
TEMPS TO BOTTOM OUT IN THE UPPER 20S AND LOWER 30S ACROSS MUCH OF
THE AREA. LIGHTEST WINDS AND THUS COLDEST TEMPS ARE EXPECTED ACROSS
THE WESTERN CWA...WHILE SLIGHTLY STRONGER WINDS WILL KEEP TEMPS A
BIT WARMER FURTHER EAST. WILL ISSUE A FREEZE WATCH FOR ALL LOCATIONS
ALONG AND WEST OF I-55...WHERE SEVERAL HOURS OF SUB-FREEZING
CONDITIONS ARE EXPECTED LATE FRIDAY NIGHT INTO SATURDAY MORNING.
COOL/DRY WEATHER WILL PERSIST THROUGH THE WEEKEND...AS SURFACE
HIGH PRESSURE REMAINS OVER THE REGION. DAYTIME HIGHS WILL ONLY
REACH THE LOWER 50S BOTH DAYS...WHILE OVERNIGHT LOWS DIP INTO THE
UPPER 20S AND LOWER 30S.
LONG TERM...MONDAY THROUGH THURSDAY
QUIET WEATHER IS EXPECTED THROUGH THE ENTIRE EXTENDED PERIOD...AS
THE REMNANTS OF HURRICANE SANDY CREATE A BLOCKING PATTERN ACROSS
THE CONUS. CENTRAL ILLINOIS WILL REMAIN IN THE SUBSIDENCE REGION
ON THE BACK SIDE OF THE POWERFUL EAST COAST SYSTEM...RESULTING IN
COOL/DRY WEATHER THROUGH THURSDAY. AS PRESSURE GRADIENT TIGHTENS
EARLY NEXT WEEK...MAY SEE SOME INCREASE IN NORTHEASTERLY WINDS
AND A SUBSEQUENT RE-ENFORCING OF THE COOL AIRMASS ACROSS THE AREA.
AS A RESULT...AM EXPECTING A COOL WEEK AHEAD...WITH HIGHS IN THE
50S AND LOWS IN THE 30S.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE FRIDAY NIGHT THROUGH SATURDAY MORNING FOR
ILZ027>031-036>038-040>043-047>051.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
652 PM CDT THU OCT 25 2012
.DISCUSSION...
336 PM CDT
PREVIOUS DISCUSSION...
1251 PM CDT
THIS UPDATE STILL VALID FOR REST OF AFTERNOON AND EARLY
EVENING...
NO BIG CHANGES IN OVERALL FORECAST THINKING THIS AFTERNOON. WE
DID SLOW FRONTAL TIMING SLIGHTLY...NOW EXPECT FRONT THROUGH THE
ROCKFORD AREA AROUND 4PM CDT AND ACROSS THE CHICAGO METRO BETWEEN
6PM AND 8PM DEPENDING ON YOUR LOCATION. LATEST RAP GUIDANCE
SUGGESTS 300-500 J/KG MUCAPE IMMEDIATELY ALONG THE FRONT WITH
50-60KT DEEP LAYER SHEAR. EXPECT CONVECTIVE COVERAGE TO INCREASE
ALONG THE FRONT OVER NEXT FEW HOURS AS A SHORTWAVE TROUGH BEGINS
TO LIFT NORTHEAST ACROSS IOWA EARLY THIS AFTERNOON. WITH INTENSE
SHEAR NOTED IMMEDIATELY ALONG AND JUST BEHIND THE FRONT...WILL
HAVE TO MONITOR FOR A MARGINAL SEVERE WEATHER THREAT THROUGH THE
AFTERNOON AND EARLY EVENING AS FAST MOVING THUNDERSTORMS ARE
EXPECTED TO DEVELOP.
BMD
DISCUSSION...LATE TONIGHT AND BEYOND...
300 PM CDT
SHARP COLD FRONT TO HAVE MOVED TO NORTH CENTRAL AND WEST CENTRAL
IN BY MIDNIGHT...WITH ONLY SOME LINGERING POST FRONTAL LIGHT
SHOWERS INTO THE OVERNIGHT HOURS FROM NORTHWEST IN TO E CENTRAL
IL. WITH THE FRONT AND THE POST FRONTAL SHOWERS HAVING MOVED EAST
OF THE LOCAL FORECAST AREA DURING THE PREDAWN HOURS THE CLEARING
SEEN UPSTREAM OVER SOUTHERN NE AND MUCH OF KS IS EXPECTED TO
SPREAD INTO NORTHWEST AND WEST CENTRAL IL BY LATE
EVENING...CONTINUING EASTWARD TO FAR NORTHEASTERN IL BY DAWN
FRIDAY.
THIS MORNING/S 12Z RAOBS SHOWED THAT BEHIND THE FRONT THAT COLD
AIR HAD PENETRATED AS FAR SOUTH AS SOUTHERN NE WITH KLBF
MEASURING AN 850 HPA TEMPERATURE OF -5C. THIS IS IN CONTRAST TO
+15C REPORTED AT BOTH KTOP AND KDVN. THIS AIR WAS COLD ENOUGH TO
SUPPORT SNOW THIS MORNING IN PARTS OF MN...IA AND NE.
WHILE THE FRONTAL PASSAGE SHIFTS LOW LEVEL WINDS TO OUT OF THE
NORTH-NORTHWEST AND NORTHWEST AND DROPS SURFACE TEMPERATURES
SIGNIFICANTLY TONIGHT...THE FLOW LOCALLY 850 AND 800 HPA IS
EXPECTED TO BACK TO WEST AND THE SOUTHWEST AT INCREASING HEIGHTS.
THIS IS IN RESPONSE TO THERE ONLY VERY SLIGHT MID AND UPPER
VEERING OF THE FLOW INDICATED DUE TO ANOTHER STRONG JET MAX AND
SHORT WAVE TROUGH TO ROTATE NORTHEASTWARD FROM THEE CENTRAL
PLAINS TO THE UPPER MIDWEST DURING THE NIGHT. THIS WEST TO
SOUTHWEST FLOW ABOVE THE BOUNDARY LAYER KEEPS THE COOL AIR
OVER THE LOCAL AREA RATHER SHALLOW AND ANY PRECIPITATION
LINGERING INTO THE NIGHT IS EXPECTED TO REMAIN LIQUID...ENDING
BEFORE THE COLD AIR DEEPENS WITH THE PASSAGE OF THE UPSTREAM
SHORT WAVE.
WITH 850 HPA TEMPERATURE PROGS AVERAGING ABOUT +1 TO -2C OVER THE
FORECAST AREA DURING THE DAY FRIDAY AFTERNOON TEMPERATURES SHOULD
ONLY RECOVER TO UPPER 40S AND LOWER 50S IN THE AFTERNOON. ANOTHER
SHORT WAVE TO MOVE ACROSS THE REGION LATE FRIDAY NIGHT AND EARLY
SATURDAY REINFORCES THE LOW LEVEL COLD AIR...WHICH IS EXPECTED TO
LIMIT MAX TEMPS FOR SATURDAY TO GENERALLY THE 45-50 DEG F
RANGE...WITH SIMILAR HIGHS FOR SUNDAY AND MONDAY.
NORTHWEST WINDS GRADUALLY VEER TO NORTH FRIDAY NIGHT AND
NORTH-NORTHEAST SATURDAY BEFORE BACKING A BIT TO NORTH DURING
SUNDAY AND INTO MONDAY. WHILE TEMPERATURE DIFFERENTIAL BETWEEN
THE LAKE AND THE COLD LOW LEVEL AIR IS SUFFICIENT FOR LAKE EFFECT
INITIATION PER MODEL FORECAST TEMPERATURE PROFILES ANY
SIGNIFICANTLY VERTICAL GROWTH IS TO BE CAPPED BY AN OVERLYING
INVERSION. THUS...ONLY EXPECT SOME LAKE EFFECT CLOUDS SATURDAY
NIGHT AND SUNDAY NEAR THE LAKE AND INLAND TO THE KANKAKEE RIVER
VALLEY OF NORTHWEST IN AND FAR NORTHEAST IL...ALONG AND NEAR THE
IL-IN STATE LINE. BY SUNDAY NIGHT THIS INVERSION LESSENED AND
EVENTUALLY ELIMINATED ALLOWING A SMALL CHANCE OF LAKE EFFECT SNOW
AND RAIN SHOWERS SUNDAY NIGHT INTO MONDAY NIGHT.
HOW LONG THE REGION REMAINS UNDER DEEP NORTH TO NORTHWEST FLOW
AND THE VERY COOL AIR MASS DEPENDS ON HOW THE HURRICANE SANDY
INTERACTS WITH THE UPPER TROUGH TO BE LOCATED FROM WESTERN HUDSON
BAY ACROSS ONTARIO AND THE UPPER GREAT LAKES MONDAY. MODELS IN
PRETTY GOOD AGREEMENT IN TURNING SANDY NORTH-NORTHWESTWARD TO
OVER THE MID ATLANTIC AND SOUTHERN NEW ENGLAND COASTS LATE
TUESDAY AND TUESDAY NIGHT. MODELS THEN CONTINUE TO MOVE THE
EXTRA- TROPICAL SYSTEM NORTH-NORTHWEST OVER THE LOWER GREAT LAKES
DURING LATER TUESDAY AND TUESDAY NIGHT...AND TO FAR SOUTHERN
QUEBEC BY THURSDAY MORNING. THIS SUGGESTS THAT THE VERY COOL AIR
MASS WILL BE LOCKED IN PLACE OVER THE REGION UNTIL AT LEAST LATE
INTO NEXT WEEK KEEPING THE STRING OF BELOW NORMAL TEMPERATURE
CONDITIONS GOING.
SOME INDICATION THAT AS THE SYSTEM MOVES TO THE LOWER GREAT LAKES
AND SOUTHERN QUEBEC THAT MOISTURE WILL BE WRAPPED WEST AND
SOUTHWESTWARD TO THE UPPER GREAT LAKES FOR LATER TUESDAY AND
WEDNESDAY WHICH BRINGS A SLIGHT CHANCE RAIN OR RAIN AND SNOW
ALMOST TO THE WESTERN SHORE OF LAKE MI. HAVE SLIGHT CHANCES INTO
NORTHWEST IN WHILE HAVE KEPT NORTHEAST IL BELOW THE SLIGHT CHANCE
POP THRESHOLD AS WAY TOO MUCH UNCERTAINTY AT THIS POINT.
TRS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* RAIN AND SLIGHT CHC OF TSRA EARLY THIS EVENING
* GUSTY WEST WINDS VEERING NORTHWEST WITH SLOWLY EASING GUSTS
* MVFR CIGS LIKELY INTO FRIDAY MORNING
IZZI
//DISCUSSION...UPDATED 00Z...
STRONG COLD FRONT HAS MOVED EAST OF THE TERMINALS EARLY THIS
EVENING HOWEVER BAND OF RAIN LAGGING BEHIND THE FRONT STILL POISED
TO AFFECT THE TERMINALS EARLY THIS EVENING. IFR CIGS UPSTREAM HAVE
BEEN BRIEF AND VERY ISOLATED SO HAVE OPTED TO REMOVE MENTION OF
IFR CIGS IN THE TAFS EARLY THIS EVENING. MODELS STRONGLY SUGGEST
SKIES WILL CLEAR OUT BY LATE EVENING...HOWEVER OUR FRIEND MR.
SATELLITE SEEMS TO SAY OTHERWISE SHOWING EXTENSIVE OVC STRATUS
DECK EXTENDING FROM HERE NORTHWESTWARD TO ALBERTA CANADA. GIVEN
THE CONTINUED COLD AIR ADVECTION AND STRATUS APPARENTLY TRAPPED
BENEATH INVERSION HAVE OPTED TO GO MUCH MORE PESSIMISTIC WITH
THIS TAF ISSUANCE WITH MVFR CIGS INTO FRIDAY MORNING. CLOUD COVER
SHOULD PREVENT DECOUPLING ALLOW WINDS TO MAINTAIN SOME GUSTINESS
THROUGH THE NIGHT.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* HIGH CONFIDENCE IN FORECAST THROUGH TONIGHT
* LOW-MEDIUM CONFIDENCE ON CIGS FRIDAY
IZZI
//OUTLOOK FOR ORD/MDW FOR 12Z SATURDAY-12Z THURSDAY...UPDATED 00Z...
SATURDAY THROUGH MONDAY...GENERALLY VFR. SMALL THREAT OF
LOCALIZED LAKE EFFECT MVFR CIGS AND SLIGHT CHANCE OF SHRA.
TUESDAY AND WEDNESDAY...VFR.
IZZI
&&
.MARINE...
347 AM...THE GRADIENT WILL CONTINUE TO TIGHTEN THIS MORNING AS
LOW LEVEL WINDS STRENGTHEN AHEAD OF AN APPROACHING COLD FRONT.
ALREADY HAD A SHIP WEST OF BEAVER ISLAND OF 32 KTS AT 07Z.
CONTINUED THE OCCASIONAL GALE GUST WORDING BUT DESPITE A VERY
STRONG MARINE LAYER/INVERSION...ITS POSSIBLE THAT MORE PREVAILING
GALES MAY DEVELOP LATER THIS MORNING AND CONTINUE THIS
AFTERNOON...MAINLY OVER THE NORTHERN THIRD/HALF OF THE LAKE. THIS
WILL NEED TO BE MONITORED FOR A POSSIBLE GALE WARNING. THE COLD
FRONT WILL MOVE ACROSS THE LAKE LATE THIS AFTERNOON INTO EARLY
THIS EVENING... SHIFTING WINDS TO THE NORTHWEST AND STRONG GUSTS
MAY ACCOMPANY THE PASSAGE OF THE FRONT. NORTHWEST WINDS WILL
SLOWLY DIMINISH TO 15-25 KTS FRIDAY AS HIGH PRESSURE BUILDS ACROSS
THE PLAINS. THIS HIGH WILL SPREAD EAST ACROSS THE WESTERN LAKES
FRIDAY NIGHT INTO SATURDAY WITH WINDS DIMINISHING FURTHER BUT THE
HIGH THEN BECOMES STATIONARY ACROSS THE WESTERN LAKES AS THE
STRONG REMNANTS OF SANDY MOVE NORTH ALONG THE EAST COAST SUNDAY
AND MONDAY. THERE REMAINS QUITE A BIT OF UNCERTAINTY EARLY/MID
NEXT WEEK BUT IF CURRENT TRENDS CONTINUE...THERE COULD BE A
PROLONGED PERIOD OF NORTHERLY WINDS. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ669-LMZ868-LMZ870 UNTIL 10 PM THURSDAY.
SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM SATURDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
642 PM CDT THU OCT 25 2012
.DISCUSSION...
ISSUED 258 PM CDT THU OCT 25 2012
SHORT TERM...TONIGHT THROUGH SUNDAY
19Z/2PM SURFACE ANALYSIS INDICATES STRONG COLD FRONT HAS PUSHED
EAST OF THE MISSISSIPPI RIVER...WITH WINDS TURNING NORTHWESTERLY
AT BOTH KMQB AND KGBG. LATEST SATELLITE/RADAR IMAGERY IS SHOWING
INCREASING COVERAGE OF POST-FRONTAL PRECIP ACROSS EASTERN IOWA AND
NORTHERN MISSOURI. AS FRONT MOVES FURTHER EAST...SHOWERS AND
THUNDERSTORMS WILL SPREAD INTO WEST-CENTRAL ILLINOIS OVER THE NEXT
COUPLE OF HOURS...THEN FURTHER EAST TOWARD THE INDIANA BORDER
BETWEEN 03Z AND 06Z. WILL CARRY CATEGORICAL POPS ACROSS THE BOARD
THIS EVENING...THEN WILL LINGER RAIN CHANCES ONLY ACROSS THE E/SE
KILX CWA AFTER MIDNIGHT. TOTAL RAINFALL WILL GENERALLY RANGE FROM
ONE QUARTER TO ONE HALF AN INCH...WITH ISOLATED HIGHER AMOUNTS
WITHIN STORMS. ONCE FRONT PASSES...MUCH COLDER AIRMASS WILL SPILL
INTO THE AREA ON GUSTY W/NW WINDS. WINDS MAY GUST AS HIGH AS 30 MPH
AT TIMES IMMEDIATELY BEHIND THE BOUNDARY BEFORE SLOWLY DIMINISHING
LATER. OVERNIGHT LOW TEMPERATURES WILL RANGE FROM THE MIDDLE 30S
ACROSS THE ILLINOIS RIVER VALLEY...TO THE UPPER 40S NEAR THE
INDIANA BORDER.
12Z OCT 25 MODELS ARE A BIT FASTER WITH FROPA THAN PREVIOUS
RUNS...WITH BOUNDARY WELL EAST INTO INDIANA BY 12Z FRI. AS A
RESULT...HAVE ONLY LINGERED CHANCE POPS FOR SHOWERS ACROSS THE FAR
E/SE CWA INTO FRIDAY MORNING...WITH DRY CONDITIONS EXPECTED ACROSS
THE BOARD BY AFTERNOON. MAIN STORY ON FRIDAY WILL BE THE MUCH
COOLER WEATHER...WITH HIGH TEMPS REMAINING IN THE LOWER TO MIDDLE
50S. AS HIGH PRESSURE BUILDS IN FROM THE WEST...WINDS WILL DIMINISH TO
LESS THAN 10 MPH FRIDAY NIGHT. GIVEN CLEAR SKIES AND LIGHT
WINDS...EXCELLENT RADIATIONAL COOLING CONDITIONS WILL ALLOW LOW
TEMPS TO BOTTOM OUT IN THE UPPER 20S AND LOWER 30S ACROSS MUCH OF
THE AREA. LIGHTEST WINDS AND THUS COLDEST TEMPS ARE EXPECTED ACROSS
THE WESTERN CWA...WHILE SLIGHTLY STRONGER WINDS WILL KEEP TEMPS A
BIT WARMER FURTHER EAST. WILL ISSUE A FREEZE WATCH FOR ALL LOCATIONS
ALONG AND WEST OF I-55...WHERE SEVERAL HOURS OF SUB-FREEZING
CONDITIONS ARE EXPECTED LATE FRIDAY NIGHT INTO SATURDAY MORNING.
COOL/DRY WEATHER WILL PERSIST THROUGH THE WEEKEND...AS SURFACE
HIGH PRESSURE REMAINS OVER THE REGION. DAYTIME HIGHS WILL ONLY
REACH THE LOWER 50S BOTH DAYS...WHILE OVERNIGHT LOWS DIP INTO THE
UPPER 20S AND LOWER 30S.
LONG TERM...MONDAY THROUGH THURSDAY
QUIET WEATHER IS EXPECTED THROUGH THE ENTIRE EXTENDED PERIOD...AS
THE REMNANTS OF HURRICANE SANDY CREATE A BLOCKING PATTERN ACROSS
THE CONUS. CENTRAL ILLINOIS WILL REMAIN IN THE SUBSIDENCE REGION
ON THE BACK SIDE OF THE POWERFUL EAST COAST SYSTEM...RESULTING IN
COOL/DRY WEATHER THROUGH THURSDAY. AS PRESSURE GRADIENT TIGHTENS
EARLY NEXT WEEK...MAY SEE SOME INCREASE IN NORTHEASTERLY WINDS
AND A SUBSEQUENT RE-ENFORCING OF THE COOL AIRMASS ACROSS THE AREA.
AS A RESULT...AM EXPECTING A COOL WEEK AHEAD...WITH HIGHS IN THE
50S AND LOWS IN THE 30S.
&&
.AVIATION...
ISSUED 635 PM CDT THU OCT 25 2012
MAIN FORECAST CONCERN WILL BE WITH THE MVFR CIGS OVERNIGHT AND
HOW QUICKLY THEY WILL CLEAR OUT OF OUR AREA...IF AT ALL. THE
COLD FRONT HAS SHIFTED EAST OF CMI WITH AREAS SEEING GUSTY
NORTHWEST WINDS WHICH SHOULD CONTINUE THRU THE EVENING HOURS.
ONE MORE BAND OF RAIN WITH ISOLD THUNDER WILL PUSH ACRS THE
AREA OVER THE NEXT SEVERAL HOURS ACCOMPANIED BY OCCASIONAL
IFR CIGS WITH SOME OF THE HEAVIER DOWNPOURS. ONCE THIS LAST
BAND OF PRECIP CLEARS OUR AREA...WE WILL HAVE TO WAIT TO SEE
JUST WHAT HAPPENS WITH THE LARGE AREA OF MVFR CIGS OUT TO OUR
WEST WHICH MODELS HAVE NOT HANDLED VERY WELL. RAP FORECAST
SOUNDINGS SEEM TO BE THE ONLY MODEL SUGGESTING THE LOW LEVEL
MOISTURE WILL HANG AROUND OUR AREA A BIT LONGER THAN WHAT WAS
EARLIER THOUGHT...SO WILL TREND IN ITS DIRECTION THRU FRIDAY
MORNING. WILL GRADUALLY BRING CIGS UP BUT KEEP THEM IN THE MVFR
CAT INTO FRIDAY MORNING AND THEN SCATTER THEM OUT AT OR JUST AFTER
17Z. NORTHWEST TO NORTH WINDS WILL CONTINUE THRU THE DAY ON
FRIDAY AND MAY BECOME GUSTY AGAIN DURING THE AFTN...ESPECIALLY IF
WE CAN GET SOME SUNSHINE.
SMITH
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE FRIDAY NIGHT THROUGH SATURDAY MORNING FOR
ILZ027>031-036>038-040>043-047>051.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
237 AM CDT WED OCT 24 2012
.DISCUSSION...
ISSUED 235 AM CDT WED OCT 24 2012
2 AM TEMPERATURES ACROSS CENTRAL AND SOUTHEAST ILLINOIS ARE STILL
AT OR ABOVE THE NORMAL HIGHS FOR TODAY. HAVE SEEN MAINLY CLEAR
SKIES OVER THE AREA THE LAST FEW HOURS. HOWEVER...REGIONAL RADAR
HAS SHOWN SOME SHOWERS DEVELOPING OVER EASTERN IOWA...ALONG A
SUBTLE SHORTWAVE TRACKING INTO NORTHWEST ILLINOIS. BROADER SURFACE
MAP SHOWING SURFACE LOW PRESSURE ORGANIZING OVER WESTERN KANSAS...
WITH A WARM FRONT ARCHING NORTHEAST INTO WISCONSIN.
FORECAST CONCERNS FOR THIS PACKAGE INVOLVE NEAR RECORD HIGH
TEMPERATURES TODAY...THE RAIN ASSOCIATED WITH A STRONG COLD FRONT
ON THURSDAY/FRIDAY...AND THE MUCH COLDER CONDITIONS BEHIND THE
FRONT FOR THE WEEKEND.
SHORT TERM...TODAY THROUGH FRIDAY...
HIGH TEMPERATURES HAVE BEEN A REAL STRUGGLE THE LAST COUPLE DAYS
DUE TO THE RAIN...BUT DRY CONDITIONS EXPECTED TODAY. SOUTHERLY
WINDS GUSTING TO AROUND 25 MPH WILL HELP BRING DOWN SOME OF THE
MILDER AIR UPSTAIRS...AND MIXING DOWN FROM 850 MB WOULD SUPPORT
HIGHS JUST ABOVE 80 DEGREES. SEVERAL AREAS WILL SEE TEMPERATURES
APPROACH RECORD HIGHS AS A RESULT.
UPPER TROUGHING ALONG THE PACIFIC COAST WILL PUSH ACROSS THE
ROCKIES TONIGHT...HELPING TO PUSH THE FRONTAL BOUNDARY EASTWARD
WITH SIGNIFICANT COLD AIR ADVECTION BEHIND IT. THE NAM...ECMWF AND
CANADIAN MODELS BRING THE FRONT ACROSS MUCH OF THE CWA IN THE
AFTERNOON...REACHING THE I-57 CORRIDOR TOWARD SUNSET...BUT THE GFS
LAGS BEHIND A BIT. HAVE MAINTAINED LIKELY POPS IN THE AFTERNOON
WEST OF I-55 AND SPREAD THEM INTO THE EASTERN CWA AFTER SUNSET.
SOME WEAK CAPES AROUND 500-800 J/KG IMMEDIATELY AHEAD OF THE FRONT
WILL HELP PRODUCE SOME THUNDER DURING THE AFTERNOON AND EARLY
EVENING. WIDESPREAD SEVERE WEATHER NOT EXPECTED...BUT LOW
PROBABILITIES AROUND 5 PERCENT INDICATED IN LATEST SPC DAY2
OUTLOOK. MUCH OF THE RAIN IS POST-FRONTAL...THUS RAIN CHANCES
CONTINUE INTO FRIDAY DESPITE THE FRONT BEING WELL TO THE EAST AND
SOUTH. AN UPPER WAVE SWINGING THROUGH THE CENTRAL AND SOUTHERN
PLAINS WILL HELP ENHANCE THIS RAIN. MODELS THE LAST FEW DAYS HAVE
BEEN STRUGGLING WITH THIS SCENARIO...BUT LIKELY POPS REMAIN
JUSTIFIED ACROSS THE SOUTHEAST CWA THROUGH FRIDAY...BEFORE QUICKLY
DIMINISHING EARLY EVENING.
SIGNIFICANT COLD AIR ADVECTION BEHIND THE FRONT WILL DROP 850 MB
TEMPERATURES FROM THE MID TEENS CELSIUS TO BELOW ZERO IN LESS THAN
24 HOURS. THUS...HIGH TEMPERATURES ON FRIDAY WILL ONLY BE IN THE
LOWER 50S. HAVE SOME CONCERNS THAT THE SOUTHEAST MAY BE EVEN
COOLER DUE TO THE RAIN.
LONG TERM...SATURDAY THROUGH TUESDAY...
HIGHS IN THE UPPER 40S OR LOWER 50S WILL CONTINUE THROUGH THE
WEEKEND...AS BROAD UPPER TROUGHING REMAINS IN PLACE OVER MUCH OF
THE MISSISSIPPI VALLEY.
MAIN FOCUS THIS PERIOD WILL REMAIN WITH THE UPPER PATTERN
PROGRESSION AS TROPICAL CYCLONE SANDY MOVES NORTHWARD OFF THE EAST
COAST. A NORTHEAST CURVE IS FAVORED BY THE GFS AND CANADIAN MODELS
ON SUNDAY AND MONDAY...ALLOWING A FASTER EXIT OF THE UPPER
TROUGH. HOWEVER...THE LAST TWO RUNS OF THE ECMWF MODEL CONTINUE TO
FAVOR A CONTINUED NORTHWARD PROGRESSION AND THE STORM TAKING A
HARD LEFT TURN INTO THE NEW YORK CITY/NEW JERSEY AREA LATE MONDAY.
THAT KIND OF SCENARIO WOULD BOTTLE UP THE UPPER PATTERN PROGRESSION
INTO LATE WEEK. DRY WEATHER CURRENTLY EXPECTED EARLY NEXT WEEK
WITH A HIGH PRESSURE AXIS EXTENDING OVER THE MIDWEST...BUT WHEN
IT WILL EXIT IS STILL UP FOR GRABS.
GEELHART
&&
.AVIATION...
ISSUED 1149 PM CDT TUE OCT 23 2012
MVFR CIGS ARE EXPECTED TO DEVELOP AT MOST OF THE CENTRAL AND
EASTERN IL TAF SITES IN THE 10-13Z RANGE. A WEAK SHORTWAVE ON
WATER VAPOR IMAGERY IN CENTRAL/SRN MO WILL MOVE INTO SOUTH CENTRAL
IL THE NEXT FEW HOURS...PROVIDING ENOUGH LIFT TO PRODUCE LOW LEVEL
CLOUDS IN THE MVFR RANGE. THE O0Z NAM SOUNDINGS AND HRRR CLOUD
BASE FORECASTS BOTH POINT TO THIS AFTER 09Z. THEY ARE BOTH
INDICATING SOME ISOLATED RAIN SHOWERS...MAINLY SOUTH OF THE TAF
SITES TOWARD DAYBREAK. WILL HOLD OFF ON MENTION OF THIS LOW
COVERAGE/LOW POP PRECIP POSSIBILITY FOR NOW.
PLENTY OF MIXING AND LOW/MID LEVEL SUBSIDENCE SHOULD PRODUCE A
BREAK IN THE MVFR CIGS TOWARD EARLY AFTERNOON IN ALL OF CENTRAL
AND EASTERN IL. LOW LEVEL MOISTURE IN FORECAST SOUNDINGS...THOUGH...
SHOULD BE SUFFICIENT TO RESULT IN AT LEAST SCT CUMULUS DURING THE
AFTERNOON. THE AFOREMENTIONED MIXING AND A TIGHTENING PRESSURE
GRADIENT IS ALSO EXPECTED TO RESULT IN SOUTH WINDS GUSTING AROUND
20 TO 25 KTS FROM LATE MORNING THROUGH THE AFTERNOON.
MILLER
&&
.CLIMATE...
ISSUED 235 AM CDT WED OCT 24 2012
RECORD HIGHS FOR TODAY...
BLOOMINGTON..... 82 IN 1902
CHAMPAIGN....... 80 IN 1991+
CHARLESTON...... 83 IN 1927
EFFINGHAM....... 84 IN 1934+
JACKSONVILLE.... 84 IN 1940
LINCOLN......... 87 IN 1992
PEORIA.......... 81 IN 1963
RUSHVILLE....... 82 IN 1927+
SPRINGFIELD..... 83 IN 1963
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1149 PM CDT TUE OCT 23 2012
.DISCUSSION...
ISSUED 838 PM CDT TUE OCT 23 2012
UPDATED THE FORECAST TO REMOVE THE MENTION OF EVENING SHOWERS IN
SOUTHEAST IL...AND TO MAKE MINOR TWEAKS TO TEMPERATURES AND SKY
COVER IN THE GRIDDED FORECAST.
TEMPERATURES EARLY THIS EVENING WERE MAINLY IN THE MID 60S...WITH
A FEW LOWER 60S IN EAST CENTRAL IL. READINGS WILL ONLY FALL A FEW
MORE DEGREES AS DEW POINTS ARE FORECAST TO REMAIN IN THE UPPER 50S
TO LOWER 60S ALL NIGHT.
CLOUDS WERE MAINLY NORTH OF I-74 ACCORDING TO THE LATEST IR
SATELLITE LOOP...AND THEY WILL CONTINUE TO LIFT TO THE NORTHEAST.
AM EXPECTING A CLEAR SKY TO THEN PERSIST FOR THE NEXT SEVERAL
HOURS BEFORE LOW LEVEL CLOUDS START TO DEVELOP. THE LOWER
ATMOSPHERE IS PRIMED FOR FOG OVERNIGHT. HOWEVER...A SOUTH WIND
AROUND 10 MPH WILL KEEP FOG FROM FORMING AND INSTEAD WE SHOULD SEE
SOME LOW LEVEL CLOUDS FORM...MAINLY AFTER MIDNIGHT IN MOST
LOCATIONS. THESE ANTICIPATED CLOUDS WILL ALSO ACT TO KEEP
TEMPERATURES FAIRLY STEADY AND MILD THROUGH THE NIGHT.
&&
.AVIATION...
ISSUED 1149 PM CDT TUE OCT 23 2012
MVFR CIGS ARE EXPECTED TO DEVELOP AT MOST OF THE CENTRAL AND
EASTERN IL TAF SITES IN THE 10-13Z RANGE. A WEAK SHORTWAVE ON
WATER VAPOR IMAGERY IN CENTRAL/SRN MO WILL MOVE INTO SOUTH CENTRAL
IL THE NEXT FEW HOURS...PROVIDING ENOUGH LIFT TO PRODUCE LOW LEVEL
CLOUDS IN THE MVFR RANGE. THE O0Z NAM SOUNDINGS AND HRRR CLOUD
BASE FORECASTS BOTH POINT TO THIS AFTER 09Z. THEY ARE BOTH
INDICATING SOME ISOLATED RAIN SHOWERS...MAINLY SOUTH OF THE TAF
SITES TOWARD DAYBREAK. WILL HOLD OFF ON MENTION OF THIS LOW
COVERAGE/LOW POP PRECIP POSSIBILITY FOR NOW.
PLENTY OF MIXING AND LOW/MID LEVEL SUBSIDENCE SHOULD PRODUCE A
BREAK IN THE MVFR CIGS TOWARD EARLY AFTERNOON IN ALL OF CENTRAL
AND EASTERN IL. LOW LEVEL MOISTURE IN FORECAST SOUNDINGS...THOUGH...
SHOULD BE SUFFICIENT TO RESULT IN AT LEAST SCT CUMULUS DURING THE
AFTERNOON. THE AFOREMENTIONED MIXING AND A TIGHTENING PRESSURE
GRADIENT IS ALSO EXPECTED TO RESULT IN SOUTH WINDS GUSTING AROUND
20 TO 25 KTS FROM LATE MORNING THROUGH THE AFTERNOON.
MILLER
&&
.PREV DISCUSSION...
ISSUED 255 PM CDT TUE OCT 23 2012
SHORT TERM...TODAY THROUGH FRIDAY NIGHT
USED A BLEND OF THE 12Z MODELS FOR THIS FORECAST PACKAGE WHICH DID
NOT CHANGE THINGS TOO MUCH FROM THE PREVIOUS FORECAST PACKAGE. MAV
AND MET GUIDANCE TEMPS SIMILAR THROUGH THU NIGHT AND FOLLOWED
EXPECT LEANED ON THE WARM MAV FOR HIGHS THU...AS MODELS HAVE BEEN
TRENDING SLOWER WITH ARRIVAL OF STRONG COLD FRONT THU AFTERNOON/EVENING.
SHORT WAVE EXITING INTO INDIANA LATE THIS AFTERNOON WILL END THE
SHOWERS AND ISOLATED THUNDERSTORMS IN SE IL WITH DRY WEATHER
EXPECTED TONIGHT. DID INCREASE THE CLOUD COVER A BIT MORE TONIGHT
ESPECIALLY NORTHERN AREAS WITH MILD LOWS IN THE UPPER 50S AND
LOWER 60S...COOLEST FROM I-57 EAST.
UNSEASONABLY WARM HIGHS IN THE LOWER 80S EXPECTED WEDNESDAY AS SKIES
BECOME MOSTLY SUNNY BY MIDDAY. WILL LIKELY SEE WARM HIGHS AROUND 80F
OVER EAST CENTRAL AND LOWER 80S IN SOUTHEAST IL THU WHILE AREAS NW
OF THE IL RIVER ARE IN THE LOW TO MID 70S. MODELS DRIVE A STRONG
COLD FRONT INTO NW IL BY 18Z/THU AND GETTING TO THE WABASH RIVER
BY MIDNIGHT THU NIGHT. MOST OF THE SHOWERS AND THUNDERSTORMS ARE
ALONG AND BEHIND THE COLD FRONT. SO KEPT EASTERN IL DRY THU WITH
AREAS FROM I-55 SEEING INCREASING CHANCES OF SHOWERS/THUNDERSTORMS
DURING THU AFTERNOON AND SPREADING INTO EASTERN/SE IL THU EVENING.
SPC HAS 5% RISK OF HAIL AND WIND THU AFTERNOON WEST OF I-55 AND
INTO EASTERN IL TOO THU EVENING.
HIGH PRESSURE TO BUILD IN FROM THE CENTRAL PLAINS LATE THIS WEEK
AND MODELS HAVE DIMINISHED THE CHANCES OF RAIN SHOWER QUICKER LATE
THIS WEEK...SO TRENDED THE FORECAST IN THAT DIRECTION. MUCH COLDER
AIR FILTERS INTO THE REGION BEHIND THE COLD FRONT FRI AND THIS
WEEKEND WITH LOWS IN THE LOW TO MID 30S THIS WEEKEND.
LONG TERM...SATURDAY THROUGH TUESDAY
AS STATED EARLIER...MUCH COLDER AIR EXPECTED THIS WEEKEND AND
BELOW NORMAL TEMPS EXPECTED TO LINGER THROUGH AT LEAST EARLY NEXT
WEEK. TROPICAL SYSTEM (SANDY) TO MOVE UP THE EAST COAST EARLY NEXT
WEEK AND THIS TO BE A BLOCKING PATTERN OVER IL AND SLOWING UP THE
WARM UP NEXT WEEK. GENERALLY DRY CONDITIONS EXPECTED DURING THIS TIME
AND NEAR FREEZING TEMPERATURES ARE POSSIBLE EARLY SUNDAY AND MONDAY
MORNING OVER PARTS OF CENTRAL IL ESPECIALLY NORTH OF I-70.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
159 AM EDT WED OCT 24 2012
.AVIATION...
KEPT MAINLY VFR CONDITIONS EXCEPT FOR A TEMPO MVFR GROUP EARLY.
VERY WARM AIR ALOFT WAS OVER THE AREA ALONG WITH MOIST CONDITIONS.
THE WARM AND MOIST FLOW SHOULD PERSIST AHEAD OF A COLD FRONT. EVEN
WARMER AIR WILL SPREAD NORTHEAST IN THE LOW LEVEL...WITH ANY SC
DECK EVENTUALLY BECOMING SCATTERED BY LATE MORNING. OTHERWISE...
THE FLOW WILL REMAIN FROM THE SOUTH AROUND OR UNDER 10 KNOTS.
&&
.PREV DISCUSSION... /ISSUED 351 PM EDT TUE OCT 23 2012/
SHORT TERM... /TONIGHT THROUGH WEDNESDAY NIGHT/
ONGOING PRECIP CHANCES THROUGH THIS EVENING AND CONTINUED MODERATING
TREND INTO WEDNESDAY WILL BE THE MAIN FORECAST ISSUES FOR THE SHORT
TERM.
CONVECTIVE COMPLEX AIDED BY MCV THIS MORNING HAS DIMINISHED...BUT
HAS LEFT SOME RESIDUAL COOL/STABLE LOW LEVELS. RAP INITIALIZATION
SOUNDINGS THIS AFTERNOON DO DEPICT SOME WEAK ELEVATED INSTABILITY
PERSISTING FOR 850 HPA BASED PARCELS HOWEVER. REMAINING SCATTERED
SHOWER ACTIVITY APPEARS TO BE FAIRLY WELL ALIGNED WITH WEAK DPVA
ZONE IN ADVANCE OF REMNANTS OF DAMPENING BAJA OF CALIFORNIA SHORT
WAVE. A STRONGER VORT MAX ASSOCIATED WITH THIS DECAYING TROUGH
APPEARS TO BE WORKING ACROSS SOUTHERN ILLINOIS THIS AFTERNOON AND
SHOULD REMAIN SOUTH OF FORECAST AREA. WILL CARRY SOME CHANCE POPS
LATE AFTERNOON INTO EARLY THIS EVENING IN ASSOCIATION WITH THE LEAD
SHORT WAVE...WITH PRECIP CHANCES DIMINISHING FROM WEST TO EAST THIS
EVENING. STILL CANNOT COMPLETELY RULE OUT AN ISOLD THUNDERSTORM
THROUGH 00Z GIVEN WEAK ELEVATED INSTABILITY AND PERIOD OF STRONGEST
FORCING WITH THIS SHORT WAVE. OTHERWISE...MILD CONDITIONS IN STORE
TONIGHT WITH LOCAL AREA REMAINING IN WARM SECTOR. SOME SCATTERING OF
LOW CLOUDS EXPECTED TONIGHT...AND RELATIVELY WEAK SFC GRADIENT
SHOULD ALLOW FOR MINS FROM THE MID TO UPPER 50S EAST...TO AROUND 60
FAR WEST. IF LOW CLOUDS DO SCATTER THIS EVENING...GRADIENT SHOULD
REMAIN WEAK ENOUGH FOR SOME PATCHY RADIATIONAL FOG TO DEVELOP BUT
STRENGTHENING LOW LEVEL HEIGHT GRADIENT LATE TONIGHT LENDS SOME LOW
CONFIDENCE IN THIS SCENARIO.
UNSEASONABLY WARM CONDITIONS IN STORE FOR TOMORROW AS REINFORCING
LOW LEVEL THERMAL RIDGE IN THE LEE OF THE ROCKIES ADVECTS NORTHEAST
INTO THE SOUTHERN GREAT LAKES. SOME LINGERING STRATUS IS POSSIBLE
MAINLY ACROSS FAR NORTH AND FAR EAST WEDNESDAY MORNING...BUT MOST
LOCATIONS SHOULD HAVE PLENTY OF AFTERNOON SUNSHINE. DESPITE LIMITED
MIXING HEIGHTS...MIXING TO 900 HPA SHOULD SUPPORT HIGHS IN THE UPPER
70S WHICH IS INLINE WITH PREVIOUS FORECAST. THE RECORD HIGH AT KSBN
FOR OCTOBER 24TH IS 79 SET BACK IN 1975 WHICH DOES APPEAR TO BE AT
RISK OF BEING REACHED. DRY...MILD CONDITIONS TO CONTINUE THROUGH
WEDNESDAY NIGHT AS AREA REMAINS IN WARM SECTOR. SOME DRIER LOW LEVEL
AIR WILL ADVECT NORTHWARD IN ADVANCE OF NEXT SIGNIFICANT UPPER
LEVEL TROUGH DIGGING ACROSS THE ROCKIES WHICH MAY TEND TO OFFSET THE
STRONGER GRADIENT WEDNESDAY NIGHT FOR LOWS SIMILAR TO THAT OF
TONIGHT.
LONG TERM... /THURSDAY THROUGH TUESDAY/
ENERGY FROM CLOSED LOW OFF THE WEST COAST WILL BEGIN TO TRANSLATE
EASTWARD WITH TIME AND BRING A CONTINUATION OF ACTIVE WEATHER AND
MUCH COOLER TEMPERATURES TO THE REGION.
THURSDAY THROUGH FRIDAY...
EFFECTS OF LARGE TROUGH DIGGING INTO THE PLAINS WILL FURTHER IMPACT
THE REGION WITH WARMEST AIR ARRIVING JUST AHEAD OF APPROACHING COLD
FRONT. MODEL SOUNDINGS SUGGEST MOSTLY SUNNY SKIES SHOULD ALLOW
MIXING THROUGH AT LEAST 900 MB AND POSSIBLY 850 MB YIELDING HIGHS
WELL INTO THE 70S WITH A FEW SPOTS RUNNING TOWARDS 80
POSSIBLE...ESPECIALLY SE. COLD FRONT WILL MOVE TOWARDS THE AREA BY
LATE AFTERNOON...INCREASING CLOUDS JUST AHEAD OF IT WITH EASTWARD
TREND EXPECTED IN TERMS OF MSTR THROUGH THURS NGT. MINOR DIFFERENCES
IN EXACT TIMING OF WIND SHIFT (GIVE OR TAKE A FEW HOURS) WITH ALL
MODELS GENERALLY AGREEING OF A SLOW PUSH AS WAVES MOVE ALONG THE
FRONT. AREA OF POST FRONTAL SHOWERS/STORMS ARE EXPECTED TO DEVELOP
TO THE WEST AND ENTER WESTERN AREAS DURING THE EVENING. COMBINATION
OF SOME DRY AIR ENTRAINMENT AND LESS OPTIMAL TIME FRAME FOR FROPA
MAY ALLOW FOR A DECREASE IN COVERAGE OF PRECIP INTO THE OVERNIGHT
HOURS. MODELS THEN REFIRE SHOWERS IN MAINLY EASTERN AREAS ON FRIDAY
AS MAIN ENERGY FINALLY DIGS IN AND PUSHES FRONT OUT OF THE AREA.
WITH INCREASED CLOUD COVER AND CAA UNDERWAY HIGHS ON FRIDAY WILL BE
A GOOD 15 TO 25 DEGREES COLDER THAN THURSDAY.
SATURDAY THROUGH TUESDAY...
CONFIDENCE IN FORECAST BEGINS TO WANE DURING THIS TIME FRAME WITH
MODEL CAMP GENERALLY SPLIT ON HANDLING ON INTERACTION BETWEEN
LONGWAVE TROUGH OVER THE GREAT LAKES AND TROPICAL CYCLONE SANDY OVER
THE WEEKEND INTO NEXT WEEK. INITIALLY...CONTINUED NW TO N FLOW OVER
THE LAKES WILL LIKELY KEEP LAKE EFFECT CLOUD COVER AND SOME CHANCES
FOR SHOWERS AROUND...POSSIBLY MIXED WITH SNOW. EXACT TRAJECTORIES
AND AMOUNT OF RESIDENT MSTR REMAIN IN QUESTION THIS FAR OUT.
GENERALLY WENT WITH COMBO OF PREV AND CONSALL TO HANDLE THIS TIME
FRAME.
RAN PRETTY MUCH WITH EITHER ALLBLEND OF GUIDANCE OR CONSALL FOR MANY
PARAMETERS INTO TUESDAY AS EXACT DETAILS OF EVOLUTION OF EAST COAST
SYSTEM REMAIN IN FLUX. ECMWF/GEM HAVE REMAINED CONSISTENT ON A
STRONG WESTWARD PULL OF THE TROPICAL SYSTEM INTO THE EASTERN STATES
VS GFS/GEFS SENDING IT OUT TO SEA. GIVEN THE PATTERN OF LATE NOD
GIVEN TO ECMWF/GEM...RESULTING IN ADDITION OF LOW END POPS TUESDAY
WHEN PROXIMITY OF ANY WRAP AROUND MSTR WOULD BE MOST FAVORABLE.
ALLBLEND RAN A BIT TOO HIGH SO WAS TEMPERED SOMEWHAT TO REMAIN
CONSERVATIVE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SHORT TERM...MARSILI
LONG TERM...FISHER
AVIATION...SKIPPER
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
259 PM CDT WED OCT 24 2012
...UPDATED LONG TERM DISCUSSION...
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 328 AM CDT WED OCT 24 2012
THE MAIN FORECAST CHALLENGES ARE, AREAS OF STRATUS AND DENSE FOG
THIS MORNING IN THE NORTH FA, FIRE WEATHER CONDITIONS IN FAR
SOUTHWESTERN KANSAS THIS AFTERNOON, HIGH TEMPERATURES ALONG A
FRONTAL BOUNDARY THIS AFTERNOON, CHANCES FOR THUNDERSTORMS THIS
EVENING, AND STRONG WINDS TONIGHT WITH A COLD FRONT.
A STRONG UPPER LEVEL JET WILL MOVE THROUGH THE NORTHERN PLAINS THIS
MORNING WITH A COLD FRONT TRAILING SOUTHWARD FROM NORTHEASTERN
NEBRASKA AND INTO CENTRAL AND WEST CENTRAL KANSAS. THIS FRONTAL
BOUNDARY MAY PUSH TO NEAR A GARDEN CITY TO DODGE CITY AND HAYS LINE
BY THIS MORNING, THEN BEGIN TO STALL AND LIFT SLOWLY NORTH AHEAD OF
A RE-DEVELOPING SURFACE LOW IN SOUTHEASTERN COLORADO. THE HRRR IS
DEPICTING AN AREA OF STRATUS AND DENSE FOG ALONG AND NORTH OF THE
FRONTAL BOUNDARY THIS MORNING. WILL GO AHEAD AND ISSUE A DENSE FOG
ADVISORY UNTIL 10 AM FROM SCOTT TO RUSH COUNTY AND NORTH. THIS
AREA IS ALSO DEPICTED BY THE HRRR MODEL FOR DENSE FOG. THEN THE
NEXT FORECAST CHALLENGE IS THE POSITION OF THE FRONTAL BOUNDARY BY
MAX HEATING THIS AFTERNOON. THE NAM IS IN LINE WITH OTHER MODELS
SHOWING THE BOUNDARY NEAR A SYRACUSE TO GARDEN CITY TO JUST NORTH
OF DODGE CITY TO A LACROSSE LINE BY 4 TO 7 PM. HAVE COOLED DAYTIME
HIGHS DOWN INTO THE LOW TO MID 70S NORTH OF THE FRONT WITH MID TO
UPPER 80S SOUTH. SOME HIGH LEVEL CIRRUS IS ALSO FORECAST TO MOVE
ACROSS WESTERN KANSAS INTO MID AFTERNOON WHICH MAY HELP TO HOLD
TEMPS DOWN FROM HITTING 90 ALONG OUR BORDER WITH OKLAHOMA. SOUTH
TO SOUTHWEST WINDS OF 15 TO 25 MPH WILL BE THE STRONGEST, WITH THE
DEEPEST MIXING, FROM JOHNSON CITY TO ULYSSES TO PRATT AND SOUTH TO
THE OKLAHOMA BORDER. A DRYLINE IS FORECAST TO PUSH EAST TO THE
AREA JUST EAST OF DODGE CITY TO ASHLAND THIS AFTERNOON THEN
RETREAT AGAIN TONIGHT.
FOR TONIGHT A STRONG UPPER LEVEL JET STREAK AND UPPER LEVEL
SHORTWAVE TROUGH WILL MOVE OUT OF THE COLORADO ROCKIES AND GREAT
BASIN AND INTO THE PLAINS. THIS SYSTEM WILL PUSH A STRONG COLD FRONT
ACROSS WESTERN KANSAS TONIGHT WITH NORTH WINDS INCREASING TO 25 TO
35 MPH AND GUSTY. WILL LET DAY SHIFT TAKE ANOTHER LOOK FOR A
POSSIBLE WIND ADVISORY. THE FRONT IS FORECAST TO MOVE THROUGH
HAYS BY 9 PM, THEN THROUGH GARDEN CITY AND DODGE CITY JUST BEFORE
MIDNIGHT AND FINALLY ACROSS MEDICINE LODGE BY 3 AM. THE MID LEVEL
COLD POOL IS FORECAST TO STAY JUST NORTH INTO NORTHERN KANSAS SO
THE CHANCES FOR PRE-FRONTAL THUNDERSTORMS LOOK LOW FOR TONIGHT.
HOWEVER JUST BEHIND THE FRONT THE MODELS ARE BREAKING OUT SOME
ELEVATED SHOWERS AND THUNDERSTORMS MAINLY IN THE WAKEENEY TO HAYS
AREA AND SOUTH TO LARNED AND MEDICINE LODGE. WILL MAINTAIN A 20-30
POP TO COVER. THE MAIN HAZARD WOULD BE LIGHTNING AS THE REGION OF
HIGHER CAPE SHIFTS EAST OF THE COLD FRONT. WITH GOOD MIXING
TONIGHT OUR OVERNIGHT LOWS SHOULD BE DOMINATED BY COLD AIR
ADVECTION AND NOT BY RADIATIONAL COOLING. SOME STRATUS WILL LIKELY
FOLLOW THE COLD FRONT WITH INCREASING CLOUDS INTO THE MORNING.
OVERNIGHT LOWS WILL BE IN THE UPPER 30S WEST AND NORTH TO THE MID
TO UPPER 40S SOUTHEAST FA FROM LARNED TO DODGE CITY AND ASHLAND
AND SOUTH.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 256 PM CDT WED OCT 24 2012
THE EARLY PART OF THE EXTENDED PERIOD WILL BE CHARACTERIZED BY A
BROAD LONGWAVE UPPER LEVEL TROUGH OVER CENTRAL NORTH AMERICA WITH
SHORTWAVE IMPULSES MOVING THROUGH THE MAIN TROUGH. FOLLOWING THE
FIRST SHORTWAVE TROUGH LATER TONIGHT...ANOTHER SHORTWAVE WILL BE
MOVING OUT OVER THE CENTRAL HIGH PLAINS LATE THURSDAY NIGHT INTO
FRIDAY. THE ATMOSPHERE OVER WESTERN KANSAS WILL BE CONSIDERABLY
DRIER AND THE MODELS ARE ONLY INDICATING SOME MID LEVEL MOISTURE
OVER THE AREA. THE PAST SEVERAL RUNS OF THE VARIOUS MODELS HAVE BEEN
SHOWING SOME QPF BREAKING OUT WITH THIS WAVE. THIS APPEARS TO BE
PARTIALLY UPSLOPE DRIVEN AS IT IS CONFINED TO THE HIGHER TERRAIN
ALONG THE EASTERN SLOPES OF THE ROCKIES. THE 12Z ECMWF TRIES TO
BRING SOME VERY LIGHT PRECIPITATION OUT ACROSS SOUTHWEST KANSAS WITH
THE WAVE DURING THE MORNING HOURS ON FRIDAY. SOUNDING PROFILES ARE
COLD ENOUGH THAT THIS COULD BE IN THE FORM OF FLURRIES. THE MODELS
CONTINUE TO SHOW FAIRLY DRY AIR BELOW 700 MILLIBARS SO FOR NOW WILL
LEAN AWAY FROM ANY MENTION OF LIGHT PRECIP.
STRONG SURFACE HIGH PRESSURE WILL CONTINUE TO BUILD SOUTHWARD INTO
THE CENTRAL HIGH PLAINS THURSDAY NIGHT INTO FRIDAY. LOW TEMPERATURES
BY FRIDAY MORNING COULD DIP INTO THE UPPER 20S TO LOW 30S. MANY
AREAS ACROSS SOUTHWEST INTO SOUTH CENTRAL KANSAS HAVE NOT
EXPERIENCED A HARD FREEZE YET SO A FREEZE WATCH SEEMS APPROPRIATE AT
THIS TIME. THERE IS SOME UNCERTAINTY AS TO HOW COLD IT WILL GET AS
THERE WILL BE A CONSIDERABLE AMOUNT OF MID LEVEL CLOUDS OVER THE
AREA BUT GIVEN THE COLDER DRIER AIR MOVING IN, WILL GO AHEAD WITH A
WATCH.
THE SHORTWAVE WILL MOVE EAST OF THE HIGH PLAINS ON FRIDAY WITH SKIES
CLEARING IN ITS WAKE. WITH SURFACE HIGH PRESSURE DOMINATING THE
CENTRAL HIGH PLAINS FRIDAY NIGHT INTO SATURDAY, THE THREAT FOR A
HARD FREEZE LOOKS BETTER GIVEN THE ADDED RADIATIONAL COOLING.
ANOTHER SHORTWAVE WILL BE APPROACHING THE CENTRAL PLAINS FROM THE
NORTHWEST FRIDAY NIGHT. THIS COULD SPREAD SOME HIGH CLOUDS INTO
WESTERN KANSAS DURING THE NIGHT WHICH COULD IMPACT THE OVERNIGHT
LOWS AS WELL. OBVIOUSLY SOME UNCERTAINTY IS INVOLVED BUT A WATCH
SEEMS APPROPRIATE FOR FRIDAY NIGHT AS WELL.
LATER IN THE EXTENDED PERIOD, UPPER LEVEL RIDGING IS FORECAST TO
BUILD INTO THE WESTERN AND CENTRAL PART OF THE COUNTRY. DRY WEATHER
CAN BE EXPECTED ALONG WITH A SLOW WARMING TREND AS THICKNESS VALUES
INCREASE OVER THE CENTRAL HIGH PLAINS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 600 AM CDT WED OCT 24 2012
VFR CONDITIONS EXPECTED FOR KGCK/KDDC. LIFR CIGS POSSIBLE FOR KHYS IN
ASSOCIATION WITH FG THIS MORNING. N WINDS WILL INCREASE 20-30 KT LATE
TONIGHT IN THE WAKE OF A PASSING COLD FRONT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 43 53 30 47 / 10 10 10 10
GCK 39 52 29 47 / 10 10 10 10
EHA 39 52 28 47 / 10 10 10 10
LBL 40 53 29 48 / 10 10 10 10
HYS 40 52 29 49 / 30 10 10 10
P28 50 56 34 50 / 20 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KRUSE
LONG TERM...GERARD
AVIATION...SUGDEN
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1131 AM CDT WED OCT 24 2012
...UPDATED FOR FIRE WEATHER...
.UPDATE...
ISSUED AT 1124 AM CDT WED OCT 24 2012
LOW STRATUS CLOUDS THIS MORNING WERE FAR MORE EXTENSIVE THAN
PREVIOUSLY FORECAST, AND ARE LIKELY GOING TO HAVE A MAJOR IMPACT
ON AFTERNOON TEMPERATURES. AS A RESULT, THE FORECAST WAS UPDATED TO
REFLECT A MUCH CLOSER SOLUTION TO THE RAPID REFRESH MODEL WITH
RESPECT TO SURFACE TEMPERATURES. LOW STRATUS WILL PERSIST FOR MUCH
OF THE AFTERNOON RELEGATING TEMPERATURES TO THE UPPER 50`S AND LOW
60S. WARM TEMPERATURES ARE STILL EXPECTED AHEAD OF THE FRONT.
HOWEVER, CIRRUS OVERSPREADING THE AREA MAY ALSO TEMPER MAXIMUM
TEMPERATURES ON THOSE REGIONS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 328 AM CDT WED OCT 24 2012
THE MAIN FORECAST CHALLENGES ARE, AREAS OF STRATUS AND DENSE FOG
THIS MORNING IN THE NORTH FA, FIRE WEATHER CONDITIONS IN FAR
SOUTHWESTERN KANSAS THIS AFTERNOON, HIGH TEMPERATURES ALONG A
FRONTAL BOUNDARY THIS AFTERNOON, CHANCES FOR THUNDERSTORMS THIS
EVENING, AND STRONG WINDS TONIGHT WITH A COLD FRONT.
A STRONG UPPER LEVEL JET WILL MOVE THROUGH THE NORTHERN PLAINS THIS
MORNING WITH A COLD FRONT TRAILING SOUTHWARD FROM NORTHEASTERN
NEBRASKA AND INTO CENTRAL AND WEST CENTRAL KANSAS. THIS FRONTAL
BOUNDARY MAY PUSH TO NEAR A GARDEN CITY TO DODGE CITY AND HAYS LINE
BY THIS MORNING, THEN BEGIN TO STALL AND LIFT SLOWLY NORTH AHEAD OF
A RE-DEVELOPING SURFACE LOW IN SOUTHEASTERN COLORADO. THE HRRR IS
DEPICTING AN AREA OF STRATUS AND DENSE FOG ALONG AND NORTH OF THE
FRONTAL BOUNDARY THIS MORNING. WILL GO AHEAD AND ISSUE A DENSE FOG
ADVISORY UNTIL 10 AM FROM SCOTT TO RUSH COUNTY AND NORTH. THIS
AREA IS ALSO DEPICTED BY THE HRRR MODEL FOR DENSE FOG. THEN THE
NEXT FORECAST CHALLENGE IS THE POSITION OF THE FRONTAL BOUNDARY BY
MAX HEATING THIS AFTERNOON. THE NAM IS IN LINE WITH OTHER MODELS
SHOWING THE BOUNDARY NEAR A SYRACUSE TO GARDEN CITY TO JUST NORTH
OF DODGE CITY TO A LACROSSE LINE BY 4 TO 7 PM. HAVE COOLED DAYTIME
HIGHS DOWN INTO THE LOW TO MID 70S NORTH OF THE FRONT WITH MID TO
UPPER 80S SOUTH. SOME HIGH LEVEL CIRRUS IS ALSO FORECAST TO MOVE
ACROSS WESTERN KANSAS INTO MID AFTERNOON WHICH MAY HELP TO HOLD
TEMPS DOWN FROM HITTING 90 ALONG OUR BORDER WITH OKLAHOMA. SOUTH
TO SOUTHWEST WINDS OF 15 TO 25 MPH WILL BE THE STRONGEST, WITH THE
DEEPEST MIXING, FROM JOHNSON CITY TO ULYSSES TO PRATT AND SOUTH TO
THE OKLAHOMA BORDER. A DRYLINE IS FORECAST TO PUSH EAST TO THE
AREA JUST EAST OF DODGE CITY TO ASHLAND THIS AFTERNOON THEN
RETREAT AGAIN TONIGHT.
FOR TONIGHT A STRONG UPPER LEVEL JET STREAK AND UPPER LEVEL
SHORTWAVE TROUGH WILL MOVE OUT OF THE COLORADO ROCKIES AND GREAT
BASIN AND INTO THE PLAINS. THIS SYSTEM WILL PUSH A STRONG COLD FRONT
ACROSS WESTERN KANSAS TONIGHT WITH NORTH WINDS INCREASING TO 25 TO
35 MPH AND GUSTY. WILL LET DAY SHIFT TAKE ANOTHER LOOK FOR A
POSSIBLE WIND ADVISORY. THE FRONT IS FORECAST TO MOVE THROUGH
HAYS BY 9 PM, THEN THROUGH GARDEN CITY AND DODGE CITY JUST BEFORE
MIDNIGHT AND FINALLY ACROSS MEDICINE LODGE BY 3 AM. THE MID LEVEL
COLD POOL IS FORECAST TO STAY JUST NORTH INTO NORTHERN KANSAS SO
THE CHANCES FOR PRE-FRONTAL THUNDERSTORMS LOOK LOW FOR TONIGHT.
HOWEVER JUST BEHIND THE FRONT THE MODELS ARE BREAKING OUT SOME
ELEVATED SHOWERS AND THUNDERSTORMS MAINLY IN THE WAKEENEY TO HAYS
AREA AND SOUTH TO LARNED AND MEDICINE LODGE. WILL MAINTAIN A 20-30
POP TO COVER. THE MAIN HAZARD WOULD BE LIGHTNING AS THE REGION OF
HIGHER CAPE SHIFTS EAST OF THE COLD FRONT. WITH GOOD MIXING
TONIGHT OUR OVERNIGHT LOWS SHOULD BE DOMINATED BY COLD AIR
ADVECTION AND NOT BY RADIATIONAL COOLING. SOME STRATUS WILL LIKELY
FOLLOW THE COLD FRONT WITH INCREASING CLOUDS INTO THE MORNING.
OVERNIGHT LOWS WILL BE IN THE UPPER 30S WEST AND NORTH TO THE MID
TO UPPER 40S SOUTHEAST FA FROM LARNED TO DODGE CITY AND ASHLAND
AND SOUTH.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 408 AM CDT WED OCT 24 2012
THURSDAY:
WINDY CONDITIONS ARE EXPECTED IN THE WAKE OF A TRAVERSING COLD FRONT
THURSDAY MORNING WITH WIND MAGNITUDES IN THE 20 TO 30 MPH RANGE. THESE
SURFACE WINDS WILL WEAKEN BY THURSDAY AFTERNOON AS THE AXIS OF HIGHER
850 HPA WINDS SHIFTS OFF TO THE EAST AND AS SUBSIDENCE & HIGH PRESSURE
BUILDS IN. TEMPERATURES THURSDAY WILL BE BELOW NORMAL AND IN THE LOWER
50S DEG F AS COLD AIR ADVECTION CONTINUES. THE 00Z ECMWF SHOWS A 400
HPA POTENTIAL VORTICITY ANOMALY TRAVERSING ACROSS THE HIGH PLAINS LATE
THURSDAY INTO FRIDAY MORNING. NOT TOO IMPRESSED WITH PRECIPITATION CHANCES
WITH THIS AS THE BEST FORCING/POST-FRONTAL UPSLOPE FLOW LOOKS TO REMAIN
NW OF THE REGION. WILL CONTINUE SILENT POPS NOW AND GO WITH THE MORE
CONSERVATIVE ECMWF. EVEN THE 00Z GFS HAS TONED DOWN ON QPF AND KEEPS
HIGHER AMOUNTS ACROSS COLORADO.
FRIDAY:
THERE IS SOME UNCERTAINTY IN THE MINIMUM TEMPERATURES FRIDAY MORNING.
HAVE GONE WITH THE ECMWF MOS GUIDANCE. THINKING THAT THERE COULD BE
SOME MID TO HIGH LEVEL CLOUDS TRAVERSING ACROSS THE REGION IN ASSOCIATION
WITH A PASSING 90-100 KT 250 HPA JET STREAK. IN ADDITION, WINDS LOOK
TO BE AROUND 10 KT FRIDAY MORNING AND RESULTANT MIXING COULD PREVENT
TEMPS FOR RADIATING DOWN FURTHER. WILL GO WITH LOWS AROUND 30 DEG F
FOR NOW. HIGHS FRIDAY WILL BE IN THE 40S DEG F AS COOL MID TO LOW LEVEL
TEMPERATURES CONTINUE IN ASSOCIATION WITH COOL HIGH PRESSURE.
SATURDAY AND BEYOND:
SATURDAY MORNING LOOKS TO BE THE BEST SHOT FOR A FREEZE FOR MUCH OF
THE REGION. WILL GO WITH THE COOLER TEMPERATURES FROM THE ECMWF MOS
VERSUS THE WARMER ALLBLEND SOLUTION. A RIDGE OF HIGH PRESSURE WILL BUILD
ACROSS KANSAS SATURDAY MORNING. WINDS SHOULD BE FAIRLY CALM AND THE
ATMOSPHERIC COLUMN SHOULD BE FAIRLY DRY SO THIS WILL LIKELY PROVIDE
THE IDEAL ENVIRONMENT FOR RADIATIONAL COOLING. HAVE HIGHLIGHTED THIS
CONCERN IN A SPECIAL WEATHER STATEMENT. HIGHS SATURDAY WILL MODERATE
BACK INTO THE 50S.
THE REST OF THE FORECAST PERIOD FEATURES NORTHWESTERLY FLOW ALOFT AND
A GRADUAL STRENGTHENING OF A LEE SURFACE TROF/RESULTANT WAA PATTERN.
EXPECT HIGHS TO INCREASE TO THE 60S WITH LOWS IN THE 30S/40S. NO PRECIPITATION
IS EXPECTED FOR THE WEEKEND INTO THE BEGINNING OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 600 AM CDT WED OCT 24 2012
VFR CONDITIONS EXPECTED FOR KGCK/KDDC. LIFR CIGS POSSIBLE FOR KHYS IN
ASSOCIATION WITH FG THIS MORNING. N WINDS WILL INCREASE 20-30 KT LATE
TONIGHT IN THE WAKE OF A PASSING COLD FRONT.
&&
.FIRE WEATHER...
ISSUED AT 1129 AM CDT WED OCT 24 2012
EXTENSIVE LOW STRATUS IS SPREADING FARTHER SOUTHWEST OVER THE REGION
THAN PREVIOUSLY EXPECTED. AS A RESULT, IT IS LIKELY THIS LOW STRATUS
AND COOLER AIRMASS WILL MAKE A SIGNIFICANT IMPACT ON AFTERNOON HIGHS
AND WIND FIELDS. THE RED FLAG WARNING WAS CANCELED FOR THE 4
SOUTHWEST KANSAS COUNTIES IT WAS IN EFFECT FOR. NO FURTHER FIRE
WEATHER HEADLINES ARE EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 64 43 53 30 / 0 10 10 10
GCK 56 39 52 29 / 0 10 10 10
EHA 64 39 52 28 / 0 10 10 10
LBL 66 40 53 29 / 0 10 10 10
HYS 57 40 52 29 / 0 30 10 10
P28 87 50 56 34 / 0 20 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...RUSSELL
SHORT TERM...KRUSE
LONG TERM...SUGDEN
AVIATION...SUGDEN
FIRE WEATHER...RUSSELL
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1126 AM CDT WED OCT 24 2012
...UPDATED FOR CURRENT TRENDS...
.UPDATE...
ISSUED AT 1124 AM CDT WED OCT 24 2012
LOW STRATUS CLOUDS THIS MORNING WERE FAR MORE EXTENSIVE THAN
PREVIOUSLY FORECAST, AND ARE LIKELY GOING TO HAVE A MAJOR IMPACT
ON AFTERNOON TEMPERATURES. AS A RESULT, THE FORECAST WAS UPDATED TO
REFLECT A MUCH CLOSER SOLUTION TO THE RAPID REFRESH MODEL WITH
RESPECT TO SURFACE TEMPERATURES. LOW STRATUS WILL PERSIST FOR MUCH
OF THE AFTERNOON RELEGATING TEMPERATURES TO THE UPPER 50`S AND LOW
60S. WARM TEMPERATURES ARE STILL EXPECTED AHEAD OF THE FRONT.
HOWEVER, CIRRUS OVERSPREADING THE AREA MAY ALSO TEMPER MAXIMUM
TEMPERATURES ON THOSE REGIONS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 328 AM CDT WED OCT 24 2012
THE MAIN FORECAST CHALLENGES ARE, AREAS OF STRATUS AND DENSE FOG
THIS MORNING IN THE NORTH FA, FIRE WEATHER CONDITIONS IN FAR
SOUTHWESTERN KANSAS THIS AFTERNOON, HIGH TEMPERATURES ALONG A
FRONTAL BOUNDARY THIS AFTERNOON, CHANCES FOR THUNDERSTORMS THIS
EVENING, AND STRONG WINDS TONIGHT WITH A COLD FRONT.
A STRONG UPPER LEVEL JET WILL MOVE THROUGH THE NORTHERN PLAINS THIS
MORNING WITH A COLD FRONT TRAILING SOUTHWARD FROM NORTHEASTERN
NEBRASKA AND INTO CENTRAL AND WEST CENTRAL KANSAS. THIS FRONTAL
BOUNDARY MAY PUSH TO NEAR A GARDEN CITY TO DODGE CITY AND HAYS LINE
BY THIS MORNING, THEN BEGIN TO STALL AND LIFT SLOWLY NORTH AHEAD OF
A RE-DEVELOPING SURFACE LOW IN SOUTHEASTERN COLORADO. THE HRRR IS
DEPICTING AN AREA OF STRATUS AND DENSE FOG ALONG AND NORTH OF THE
FRONTAL BOUNDARY THIS MORNING. WILL GO AHEAD AND ISSUE A DENSE FOG
ADVISORY UNTIL 10 AM FROM SCOTT TO RUSH COUNTY AND NORTH. THIS
AREA IS ALSO DEPICTED BY THE HRRR MODEL FOR DENSE FOG. THEN THE
NEXT FORECAST CHALLENGE IS THE POSITION OF THE FRONTAL BOUNDARY BY
MAX HEATING THIS AFTERNOON. THE NAM IS IN LINE WITH OTHER MODELS
SHOWING THE BOUNDARY NEAR A SYRACUSE TO GARDEN CITY TO JUST NORTH
OF DODGE CITY TO A LACROSSE LINE BY 4 TO 7 PM. HAVE COOLED DAYTIME
HIGHS DOWN INTO THE LOW TO MID 70S NORTH OF THE FRONT WITH MID TO
UPPER 80S SOUTH. SOME HIGH LEVEL CIRRUS IS ALSO FORECAST TO MOVE
ACROSS WESTERN KANSAS INTO MID AFTERNOON WHICH MAY HELP TO HOLD
TEMPS DOWN FROM HITTING 90 ALONG OUR BORDER WITH OKLAHOMA. SOUTH
TO SOUTHWEST WINDS OF 15 TO 25 MPH WILL BE THE STRONGEST, WITH THE
DEEPEST MIXING, FROM JOHNSON CITY TO ULYSSES TO PRATT AND SOUTH TO
THE OKLAHOMA BORDER. A DRYLINE IS FORECAST TO PUSH EAST TO THE
AREA JUST EAST OF DODGE CITY TO ASHLAND THIS AFTERNOON THEN
RETREAT AGAIN TONIGHT.
FOR TONIGHT A STRONG UPPER LEVEL JET STREAK AND UPPER LEVEL
SHORTWAVE TROUGH WILL MOVE OUT OF THE COLORADO ROCKIES AND GREAT
BASIN AND INTO THE PLAINS. THIS SYSTEM WILL PUSH A STRONG COLD FRONT
ACROSS WESTERN KANSAS TONIGHT WITH NORTH WINDS INCREASING TO 25 TO
35 MPH AND GUSTY. WILL LET DAY SHIFT TAKE ANOTHER LOOK FOR A
POSSIBLE WIND ADVISORY. THE FRONT IS FORECAST TO MOVE THROUGH
HAYS BY 9 PM, THEN THROUGH GARDEN CITY AND DODGE CITY JUST BEFORE
MIDNIGHT AND FINALLY ACROSS MEDICINE LODGE BY 3 AM. THE MID LEVEL
COLD POOL IS FORECAST TO STAY JUST NORTH INTO NORTHERN KANSAS SO
THE CHANCES FOR PRE-FRONTAL THUNDERSTORMS LOOK LOW FOR TONIGHT.
HOWEVER JUST BEHIND THE FRONT THE MODELS ARE BREAKING OUT SOME
ELEVATED SHOWERS AND THUNDERSTORMS MAINLY IN THE WAKEENEY TO HAYS
AREA AND SOUTH TO LARNED AND MEDICINE LODGE. WILL MAINTAIN A 20-30
POP TO COVER. THE MAIN HAZARD WOULD BE LIGHTNING AS THE REGION OF
HIGHER CAPE SHIFTS EAST OF THE COLD FRONT. WITH GOOD MIXING
TONIGHT OUR OVERNIGHT LOWS SHOULD BE DOMINATED BY COLD AIR
ADVECTION AND NOT BY RADIATIONAL COOLING. SOME STRATUS WILL LIKELY
FOLLOW THE COLD FRONT WITH INCREASING CLOUDS INTO THE MORNING.
OVERNIGHT LOWS WILL BE IN THE UPPER 30S WEST AND NORTH TO THE MID
TO UPPER 40S SOUTHEAST FA FROM LARNED TO DODGE CITY AND ASHLAND
AND SOUTH.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 408 AM CDT WED OCT 24 2012
THURSDAY:
WINDY CONDITIONS ARE EXPECTED IN THE WAKE OF A TRAVERSING COLD FRONT
THURSDAY MORNING WITH WIND MAGNITUDES IN THE 20 TO 30 MPH RANGE. THESE
SURFACE WINDS WILL WEAKEN BY THURSDAY AFTERNOON AS THE AXIS OF HIGHER
850 HPA WINDS SHIFTS OFF TO THE EAST AND AS SUBSIDENCE & HIGH PRESSURE
BUILDS IN. TEMPERATURES THURSDAY WILL BE BELOW NORMAL AND IN THE LOWER
50S DEG F AS COLD AIR ADVECTION CONTINUES. THE 00Z ECMWF SHOWS A 400
HPA POTENTIAL VORTICITY ANOMALY TRAVERSING ACROSS THE HIGH PLAINS LATE
THURSDAY INTO FRIDAY MORNING. NOT TOO IMPRESSED WITH PRECIPITATION CHANCES
WITH THIS AS THE BEST FORCING/POST-FRONTAL UPSLOPE FLOW LOOKS TO REMAIN
NW OF THE REGION. WILL CONTINUE SILENT POPS NOW AND GO WITH THE MORE
CONSERVATIVE ECMWF. EVEN THE 00Z GFS HAS TONED DOWN ON QPF AND KEEPS
HIGHER AMOUNTS ACROSS COLORADO.
FRIDAY:
THERE IS SOME UNCERTAINTY IN THE MINIMUM TEMPERATURES FRIDAY MORNING.
HAVE GONE WITH THE ECMWF MOS GUIDANCE. THINKING THAT THERE COULD BE
SOME MID TO HIGH LEVEL CLOUDS TRAVERSING ACROSS THE REGION IN ASSOCIATION
WITH A PASSING 90-100 KT 250 HPA JET STREAK. IN ADDITION, WINDS LOOK
TO BE AROUND 10 KT FRIDAY MORNING AND RESULTANT MIXING COULD PREVENT
TEMPS FOR RADIATING DOWN FURTHER. WILL GO WITH LOWS AROUND 30 DEG F
FOR NOW. HIGHS FRIDAY WILL BE IN THE 40S DEG F AS COOL MID TO LOW LEVEL
TEMPERATURES CONTINUE IN ASSOCIATION WITH COOL HIGH PRESSURE.
SATURDAY AND BEYOND:
SATURDAY MORNING LOOKS TO BE THE BEST SHOT FOR A FREEZE FOR MUCH OF
THE REGION. WILL GO WITH THE COOLER TEMPERATURES FROM THE ECMWF MOS
VERSUS THE WARMER ALLBLEND SOLUTION. A RIDGE OF HIGH PRESSURE WILL BUILD
ACROSS KANSAS SATURDAY MORNING. WINDS SHOULD BE FAIRLY CALM AND THE
ATMOSPHERIC COLUMN SHOULD BE FAIRLY DRY SO THIS WILL LIKELY PROVIDE
THE IDEAL ENVIRONMENT FOR RADIATIONAL COOLING. HAVE HIGHLIGHTED THIS
CONCERN IN A SPECIAL WEATHER STATEMENT. HIGHS SATURDAY WILL MODERATE
BACK INTO THE 50S.
THE REST OF THE FORECAST PERIOD FEATURES NORTHWESTERLY FLOW ALOFT AND
A GRADUAL STRENGTHENING OF A LEE SURFACE TROF/RESULTANT WAA PATTERN.
EXPECT HIGHS TO INCREASE TO THE 60S WITH LOWS IN THE 30S/40S. NO PRECIPITATION
IS EXPECTED FOR THE WEEKEND INTO THE BEGINNING OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 600 AM CDT WED OCT 24 2012
VFR CONDITIONS EXPECTED FOR KGCK/KDDC. LIFR CIGS POSSIBLE FOR KHYS IN
ASSOCIATION WITH FG THIS MORNING. N WINDS WILL INCREASE 20-30 KT LATE
TONIGHT IN THE WAKE OF A PASSING COLD FRONT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 64 43 53 30 / 0 10 10 10
GCK 56 39 52 29 / 0 10 10 10
EHA 64 39 52 28 / 0 10 10 10
LBL 66 40 53 29 / 0 10 10 10
HYS 57 40 52 29 / 0 30 10 10
P28 87 50 56 34 / 0 20 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...RUSSELL
SYNOPSIS...RUSSELL
SHORT TERM...KRUSE
LONG TERM...SUGDEN
AVIATION...SUGDEN
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
600 AM CDT WED OCT 24 2012
...UPDATE TO AVIATION FOR 12Z TAFS...
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 328 AM CDT WED OCT 24 2012
THE MAIN FORECAST CHALLENGES ARE, AREAS OF STRATUS AND DENSE FOG
THIS MORNING IN THE NORTH FA, FIRE WEATHER CONDITIONS IN FAR
SOUTHWESTERN KANSAS THIS AFTERNOON, HIGH TEMPERATURES ALONG A
FRONTAL BOUNDARY THIS AFTERNOON, CHANCES FOR THUNDERSTORMS THIS
EVENING, AND STRONG WINDS TONIGHT WITH A COLD FRONT.
A STRONG UPPER LEVEL JET WILL MOVE THROUGH THE NORTHERN PLAINS THIS
MORNING WITH A COLD FRONT TRAILING SOUTHWARD FROM NORTHEASTERN
NEBRASKA AND INTO CENTRAL AND WEST CENTRAL KANSAS. THIS FRONTAL
BOUNDARY MAY PUSH TO NEAR A GARDEN CITY TO DODGE CITY AND HAYS LINE
BY THIS MORNING, THEN BEGIN TO STALL AND LIFT SLOWLY NORTH AHEAD OF
A RE-DEVELOPING SURFACE LOW IN SOUTHEASTERN COLORADO. THE HRRR IS
DEPICTING AN AREA OF STRATUS AND DENSE FOG ALONG AND NORTH OF THE
FRONTAL BOUNDARY THIS MORNING. WILL GO AHEAD AND ISSUE A DENSE FOG
ADVISORY UNTIL 10 AM FROM SCOTT TO RUSH COUNTY AND NORTH. THIS
AREA IS ALSO DEPICTED BY THE HRRR MODEL FOR DENSE FOG. THEN THE
NEXT FORECAST CHALLENGE IS THE POSITION OF THE FRONTAL BOUNDARY BY
MAX HEATING THIS AFTERNOON. THE NAM IS IN LINE WITH OTHER MODELS
SHOWING THE BOUNDARY NEAR A SYRACUSE TO GARDEN CITY TO JUST NORTH
OF DODGE CITY TO A LACROSSE LINE BY 4 TO 7 PM. HAVE COOLED DAYTIME
HIGHS DOWN INTO THE LOW TO MID 70S NORTH OF THE FRONT WITH MID TO
UPPER 80S SOUTH. SOME HIGH LEVEL CIRRUS IS ALSO FORECAST TO MOVE
ACROSS WESTERN KANSAS INTO MID AFTERNOON WHICH MAY HELP TO HOLD
TEMPS DOWN FROM HITTING 90 ALONG OUR BORDER WITH OKLAHOMA. SOUTH
TO SOUTHWEST WINDS OF 15 TO 25 MPH WILL BE THE STRONGEST, WITH THE
DEEPEST MIXING, FROM JOHNSON CITY TO ULYSSES TO PRATT AND SOUTH TO
THE OKLAHOMA BORDER. A DRYLINE IS FORECAST TO PUSH EAST TO THE
AREA JUST EAST OF DODGE CITY TO ASHLAND THIS AFTERNOON THEN
RETREAT AGAIN TONIGHT.
FOR TONIGHT A STRONG UPPER LEVEL JET STREAK AND UPPER LEVEL
SHORTWAVE TROUGH WILL MOVE OUT OF THE COLORADO ROCKIES AND GREAT
BASIN AND INTO THE PLAINS. THIS SYSTEM WILL PUSH A STRONG COLD FRONT
ACROSS WESTERN KANSAS TONIGHT WITH NORTH WINDS INCREASING TO 25 TO
35 MPH AND GUSTY. WILL LET DAY SHIFT TAKE ANOTHER LOOK FOR A
POSSIBLE WIND ADVISORY. THE FRONT IS FORECAST TO MOVE THROUGH
HAYS BY 9 PM, THEN THROUGH GARDEN CITY AND DODGE CITY JUST BEFORE
MIDNIGHT AND FINALLY ACROSS MEDICINE LODGE BY 3 AM. THE MID LEVEL
COLD POOL IS FORECAST TO STAY JUST NORTH INTO NORTHERN KANSAS SO
THE CHANCES FOR PRE-FRONTAL THUNDERSTORMS LOOK LOW FOR TONIGHT.
HOWEVER JUST BEHIND THE FRONT THE MODELS ARE BREAKING OUT SOME
ELEVATED SHOWERS AND THUNDERSTORMS MAINLY IN THE WAKEENEY TO HAYS
AREA AND SOUTH TO LARNED AND MEDICINE LODGE. WILL MAINTAIN A 20-30
POP TO COVER. THE MAIN HAZARD WOULD BE LIGHTNING AS THE REGION OF
HIGHER CAPE SHIFTS EAST OF THE COLD FRONT. WITH GOOD MIXING
TONIGHT OUR OVERNIGHT LOWS SHOULD BE DOMINATED BY COLD AIR
ADVECTION AND NOT BY RADIATIONAL COOLING. SOME STRATUS WILL LIKELY
FOLLOW THE COLD FRONT WITH INCREASING CLOUDS INTO THE MORNING.
OVERNIGHT LOWS WILL BE IN THE UPPER 30S WEST AND NORTH TO THE MID
TO UPPER 40S SOUTHEAST FA FROM LARNED TO DODGE CITY AND ASHLAND
AND SOUTH.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 408 AM CDT WED OCT 24 2012
THURSDAY:
WINDY CONDITIONS ARE EXPECTED IN THE WAKE OF A TRAVERSING COLD FRONT
THURSDAY MORNING WITH WIND MAGNITUDES IN THE 20 TO 30 MPH RANGE. THESE
SURFACE WINDS WILL WEAKEN BY THURSDAY AFTERNOON AS THE AXIS OF HIGHER
850 HPA WINDS SHIFTS OFF TO THE EAST AND AS SUBSIDENCE & HIGH PRESSURE
BUILDS IN. TEMPERATURES THURSDAY WILL BE BELOW NORMAL AND IN THE LOWER
50S DEG F AS COLD AIR ADVECTION CONTINUES. THE 00Z ECMWF SHOWS A 400
HPA POTENTIAL VORTICITY ANOMALY TRAVERSING ACROSS THE HIGH PLAINS LATE
THURSDAY INTO FRIDAY MORNING. NOT TOO IMPRESSED WITH PRECIPITATION CHANCES
WITH THIS AS THE BEST FORCING/POST-FRONTAL UPSLOPE FLOW LOOKS TO REMAIN
NW OF THE REGION. WILL CONTINUE SILENT POPS NOW AND GO WITH THE MORE
CONSERVATIVE ECMWF. EVEN THE 00Z GFS HAS TONED DOWN ON QPF AND KEEPS
HIGHER AMOUNTS ACROSS COLORADO.
FRIDAY:
THERE IS SOME UNCERTAINTY IN THE MINIMUM TEMPERATURES FRIDAY MORNING.
HAVE GONE WITH THE ECMWF MOS GUIDANCE. THINKING THAT THERE COULD BE
SOME MID TO HIGH LEVEL CLOUDS TRAVERSING ACROSS THE REGION IN ASSOCIATION
WITH A PASSING 90-100 KT 250 HPA JET STREAK. IN ADDITION, WINDS LOOK
TO BE AROUND 10 KT FRIDAY MORNING AND RESULTANT MIXING COULD PREVENT
TEMPS FOR RADIATING DOWN FURTHER. WILL GO WITH LOWS AROUND 30 DEG F
FOR NOW. HIGHS FRIDAY WILL BE IN THE 40S DEG F AS COOL MID TO LOW LEVEL
TEMPERATURES CONTINUE IN ASSOCIATION WITH COOL HIGH PRESSURE.
SATURDAY AND BEYOND:
SATURDAY MORNING LOOKS TO BE THE BEST SHOT FOR A FREEZE FOR MUCH OF
THE REGION. WILL GO WITH THE COOLER TEMPERATURES FROM THE ECMWF MOS
VERSUS THE WARMER ALLBLEND SOLUTION. A RIDGE OF HIGH PRESSURE WILL BUILD
ACROSS KANSAS SATURDAY MORNING. WINDS SHOULD BE FAIRLY CALM AND THE
ATMOSPHERIC COLUMN SHOULD BE FAIRLY DRY SO THIS WILL LIKELY PROVIDE
THE IDEAL ENVIRONMENT FOR RADIATIONAL COOLING. HAVE HIGHLIGHTED THIS
CONCERN IN A SPECIAL WEATHER STATEMENT. HIGHS SATURDAY WILL MODERATE
BACK INTO THE 50S.
THE REST OF THE FORECAST PERIOD FEATURES NORTHWESTERLY FLOW ALOFT AND
A GRADUAL STRENGTHENING OF A LEE SURFACE TROF/RESULTANT WAA PATTERN.
EXPECT HIGHS TO INCREASE TO THE 60S WITH LOWS IN THE 30S/40S. NO PRECIPITATION
IS EXPECTED FOR THE WEEKEND INTO THE BEGINNING OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 600 AM CDT WED OCT 24 2012
VFR CONDITIONS EXPECTED FOR KGCK/KDDC. LIFR CIGS POSSIBLE FOR KHYS IN
ASSOCIATION WITH FG THIS MORNING. N WINDS WILL INCREASE 20-30 KT LATE
TONIGHT IN THE WAKE OF A PASSING COLD FRONT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 85 43 53 30 / 0 10 10 10
GCK 79 39 52 29 / 0 10 10 10
EHA 87 39 52 28 / 0 10 10 10
LBL 87 40 53 29 / 0 10 10 10
HYS 73 40 52 29 / 0 30 10 10
P28 87 50 56 34 / 0 20 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR KSZ030-031-
043>046.
RED FLAG WARNING FROM 1 PM THIS AFTERNOON TO 7 PM CDT THIS
EVENING FOR KSZ074-075-084-085.
&&
$$
SHORT TERM...KRUSE
LONG TERM...SUGDEN
AVIATION...SUGDEN
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
408 AM CDT WED OCT 24 2012
...UPDATE TO LONG TERM DISCUSSION...
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 328 AM CDT WED OCT 24 2012
THE MAIN FORECAST CHALLENGES ARE, AREAS OF STRATUS AND DENSE FOG
THIS MORNING IN THE NORTH FA, FIRE WEATHER CONDITIONS IN FAR
SOUTHWESTERN KANSAS THIS AFTERNOON, HIGH TEMPERATURES ALONG A
FRONTAL BOUNDARY THIS AFTERNOON, CHANCES FOR THUNDERSTORMS THIS
EVENING, AND STRONG WINDS TONIGHT WITH A COLD FRONT.
A STRONG UPPER LEVEL JET WILL MOVE THROUGH THE NORTHERN PLAINS THIS
MORNING WITH A COLD FRONT TRAILING SOUTHWARD FROM NORTHEASTERN
NEBRASKA AND INTO CENTRAL AND WEST CENTRAL KANSAS. THIS FRONTAL
BOUNDARY MAY PUSH TO NEAR A GARDEN CITY TO DODGE CITY AND HAYS LINE
BY THIS MORNING, THEN BEGIN TO STALL AND LIFT SLOWLY NORTH AHEAD OF
A RE-DEVELOPING SURFACE LOW IN SOUTHEASTERN COLORADO. THE HRRR IS
DEPICTING AN AREA OF STRATUS AND DENSE FOG ALONG AND NORTH OF THE
FRONTAL BOUNDARY THIS MORNING. WILL GO AHEAD AND ISSUE A DENSE FOG
ADVISORY UNTIL 10 AM FROM SCOTT TO RUSH COUNTY AND NORTH. THIS
AREA IS ALSO DEPICTED BY THE HRRR MODEL FOR DENSE FOG. THEN THE
NEXT FORECAST CHALLENGE IS THE POSITION OF THE FRONTAL BOUNDARY BY
MAX HEATING THIS AFTERNOON. THE NAM IS IN LINE WITH OTHER MODELS
SHOWING THE BOUNDARY NEAR A SYRACUSE TO GARDEN CITY TO JUST NORTH
OF DODGE CITY TO A LACROSSE LINE BY 4 TO 7 PM. HAVE COOLED DAYTIME
HIGHS DOWN INTO THE LOW TO MID 70S NORTH OF THE FRONT WITH MID TO
UPPER 80S SOUTH. SOME HIGH LEVEL CIRRUS IS ALSO FORECAST TO MOVE
ACROSS WESTERN KANSAS INTO MID AFTERNOON WHICH MAY HELP TO HOLD
TEMPS DOWN FROM HITTING 90 ALONG OUR BORDER WITH OKLAHOMA. SOUTH
TO SOUTHWEST WINDS OF 15 TO 25 MPH WILL BE THE STRONGEST, WITH THE
DEEPEST MIXING, FROM JOHNSON CITY TO ULYSSES TO PRATT AND SOUTH TO
THE OKLAHOMA BORDER. A DRYLINE IS FORECAST TO PUSH EAST TO THE
AREA JUST EAST OF DODGE CITY TO ASHLAND THIS AFTERNOON THEN
RETREAT AGAIN TONIGHT.
FOR TONIGHT A STRONG UPPER LEVEL JET STREAK AND UPPER LEVEL
SHORTWAVE TROUGH WILL MOVE OUT OF THE COLORADO ROCKIES AND GREAT
BASIN AND INTO THE PLAINS. THIS SYSTEM WILL PUSH A STRONG COLD FRONT
ACROSS WESTERN KANSAS TONIGHT WITH NORTH WINDS INCREASING TO 25 TO
35 MPH AND GUSTY. WILL LET DAY SHIFT TAKE ANOTHER LOOK FOR A
POSSIBLE WIND ADVISORY. THE FRONT IS FORECAST TO MOVE THROUGH
HAYS BY 9 PM, THEN THROUGH GARDEN CITY AND DODGE CITY JUST BEFORE
MIDNIGHT AND FINALLY ACROSS MEDICINE LODGE BY 3 AM. THE MID LEVEL
COLD POOL IS FORECAST TO STAY JUST NORTH INTO NORTHERN KANSAS SO
THE CHANCES FOR PRE-FRONTAL THUNDERSTORMS LOOK LOW FOR TONIGHT.
HOWEVER JUST BEHIND THE FRONT THE MODELS ARE BREAKING OUT SOME
ELEVATED SHOWERS AND THUNDERSTORMS MAINLY IN THE WAKEENEY TO HAYS
AREA AND SOUTH TO LARNED AND MEDICINE LODGE. WILL MAINTAIN A 20-30
POP TO COVER. THE MAIN HAZARD WOULD BE LIGHTNING AS THE REGION OF
HIGHER CAPE SHIFTS EAST OF THE COLD FRONT. WITH GOOD MIXING
TONIGHT OUR OVERNIGHT LOWS SHOULD BE DOMINATED BY COLD AIR
ADVECTION AND NOT BY RADIATIONAL COOLING. SOME STRATUS WILL LIKELY
FOLLOW THE COLD FRONT WITH INCREASING CLOUDS INTO THE MORNING.
OVERNIGHT LOWS WILL BE IN THE UPPER 30S WEST AND NORTH TO THE MID
TO UPPER 40S SOUTHEAST FA FROM LARNED TO DODGE CITY AND ASHLAND
AND SOUTH.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 408 AM CDT WED OCT 24 2012
THURSDAY:
WINDY CONDITIONS ARE EXPECTED IN THE WAKE OF A TRAVERSING COLD FRONT
THURSDAY MORNING WITH WIND MAGNITUDES IN THE 20 TO 30 MPH RANGE. THESE
SURFACE WINDS WILL WEAKEN BY THURSDAY AFTERNOON AS THE AXIS OF HIGHER
850 HPA WINDS SHIFTS OFF TO THE EAST AND AS SUBSIDENCE & HIGH PRESSURE
BUILDS IN. TEMPERATURES THURSDAY WILL BE BELOW NORMAL AND IN THE LOWER
50S DEG F AS COLD AIR ADVECTION CONTINUES. THE 00Z ECMWF SHOWS A 400
HPA POTENTIAL VORTICITY ANOMALY TRAVERSING ACROSS THE HIGH PLAINS LATE
THURSDAY INTO FRIDAY MORNING. NOT TOO IMPRESSED WITH PRECIPITATION CHANCES
WITH THIS AS THE BEST FORCING/POST-FRONTAL UPSLOPE FLOW LOOKS TO REMAIN
NW OF THE REGION. WILL CONTINUE SILENT POPS NOW AND GO WITH THE MORE
CONSERVATIVE ECMWF. EVEN THE 00Z GFS HAS TONED DOWN ON QPF AND KEEPS
HIGHER AMOUNTS ACROSS COLORADO.
FRIDAY:
THERE IS SOME UNCERTAINTY IN THE MINIMUM TEMPERATURES FRIDAY MORNING.
HAVE GONE WITH THE ECMWF MOS GUIDANCE. THINKING THAT THERE COULD BE
SOME MID TO HIGH LEVEL CLOUDS TRAVERSING ACROSS THE REGION IN ASSOCIATION
WITH A PASSING 90-100 KT 250 HPA JET STREAK. IN ADDITION, WINDS LOOK
TO BE AROUND 10 KT FRIDAY MORNING AND RESULTANT MIXING COULD PREVENT
TEMPS FOR RADIATING DOWN FURTHER. WILL GO WITH LOWS AROUND 30 DEG F
FOR NOW. HIGHS FRIDAY WILL BE IN THE 40S DEG F AS COOL MID TO LOW LEVEL
TEMPERATURES CONTINUE IN ASSOCIATION WITH COOL HIGH PRESSURE.
SATURDAY AND BEYOND:
SATURDAY MORNING LOOKS TO BE THE BEST SHOT FOR A FREEZE FOR MUCH OF
THE REGION. WILL GO WITH THE COOLER TEMPERATURES FROM THE ECMWF MOS
VERSUS THE WARMER ALLBLEND SOLUTION. A RIDGE OF HIGH PRESSURE WILL BUILD
ACROSS KANSAS SATURDAY MORNING. WINDS SHOULD BE FAIRLY CALM AND THE
ATMOSPHERIC COLUMN SHOULD BE FAIRLY DRY SO THIS WILL LIKELY PROVIDE
THE IDEAL ENVIRONMENT FOR RADIATIONAL COOLING. HAVE HIGHLIGHTED THIS
CONCERN IN A SPECIAL WEATHER STATEMENT. HIGHS SATURDAY WILL MODERATE
BACK INTO THE 50S.
THE REST OF THE FORECAST PERIOD FEATURES NORTHWESTERLY FLOW ALOFT AND
A GRADUAL STRENGTHENING OF A LEE SURFACE TROF/RESULTANT WAA PATTERN.
EXPECT HIGHS TO INCREASE TO THE 60S WITH LOWS IN THE 30S/40S. NO PRECIPITATION
IS EXPECTED FOR THE WEEKEND INTO THE BEGINNING OF NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1224 AM CDT WED OCT 24 2012
A STRONG UPPER LEVEL JET AND ASSOCIATED UPPER LEVEL SHORTWAVE
TROUGH WILL MOVE INTO THE COLORADO ROCKIES BY LATE THIS AFTERNOON
THEN MOVE ACROSS THE PLAINS TONIGHT. THIS SYSTEM WILL FORCE A
STRONG COLD FRONT THROUGH WESTERN KANSAS TONIGHT. AHEAD OF THE
COLD FRONT EXPECT VFR CONDITIONS WITH SOUTH WINDS AROUND 10-15KT
THIS MORNING IN THE KGCK TO KDDC AREA AND LIGHT AND VARIABLE
AROUND KHYS. COULD HAVE SOME LOW STRATUS FOR A TIME IN THE KHYS
AREA BUT THERE IS SOME UNCERTAINTY. A SURFACE LOW AHEAD OF THE
COLD FRONT WILL MOVE INTO NEBRASKA WITH A WEAK FRONTAL BOUNDARY
THROUGH HAYS TO NEAR DODGE CITY AND GARDEN CITY. WINDS AT KGCK AND
KDDC MAY GO VARIABLE ALONG THIS BOUNDARY BY 13-16Z THIS MORNING.
THE STRONG COLD FRONT WILL THEN RAPIDLY SPILL SOUTHWARD ACROSS THE
TAF SITES AROUND 02Z AT KHYS, O4Z AT KGCK, AND 05Z AT KDDC AS A
FIRST GUESS OF THE NAM12. WINDS BEHIND THE COLD FRONT WILL
INCREASE RAPIDLY TO 20-35KT WITH CIGS LOWERING TO MVFR. THERE
COULD ALSO BE AN ELEVATED THUNDERSTORM IN THE KHYS AREA BETWEEN
02-06Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 85 43 53 30 / 0 10 10 10
GCK 79 39 52 29 / 0 10 10 10
EHA 87 39 52 28 / 0 10 10 10
LBL 87 40 53 29 / 0 10 10 10
HYS 73 40 52 29 / 0 30 10 10
P28 87 50 56 34 / 0 20 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR KSZ030-031-
043>046.
RED FLAG WARNING FROM 1 PM THIS AFTERNOON TO 7 PM CDT THIS
EVENING FOR KSZ074-075-084-085.
&&
$$
SHORT TERM...KRUSE
LONG TERM...SUGDEN
AVIATION...KRUSE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
336 AM CDT WED OCT 24 2012
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 328 AM CDT WED OCT 24 2012
THE MAIN FORECAST CHALLENGES ARE, AREAS OF STRATUS AND DENSE FOG
THIS MORNING IN THE NORTH FA, FIRE WEATHER CONDITIONS IN FAR
SOUTHWESTERN KANSAS THIS AFTERNOON, HIGH TEMPERATURES ALONG A
FRONTAL BOUNDARY THIS AFTERNOON, CHANCES FOR THUNDERSTORMS THIS
EVENING, AND STRONG WINDS TONIGHT WITH A COLD FRONT.
A STRONG UPPER LEVEL JET WILL MOVE THROUGH THE NORTHERN PLAINS THIS
MORNING WITH A COLD FRONT TRAILING SOUTHWARD FROM NORTHEASTERN
NEBRASKA AND INTO CENTRAL AND WEST CENTRAL KANSAS. THIS FRONTAL
BOUNDARY MAY PUSH TO NEAR A GARDEN CITY TO DODGE CITY AND HAYS LINE
BY THIS MORNING, THEN BEGIN TO STALL AND LIFT SLOWLY NORTH AHEAD OF
A RE-DEVELOPING SURFACE LOW IN SOUTHEASTERN COLORADO. THE HRRR IS
DEPICTING AN AREA OF STRATUS AND DENSE FOG ALONG AND NORTH OF THE
FRONTAL BOUNDARY THIS MORNING. WILL GO AHEAD AND ISSUE A DENSE FOG
ADVISORY UNTIL 10 AM FROM SCOTT TO RUSH COUNTY AND NORTH. THIS
AREA IS ALSO DEPICTED BY THE HRRR MODEL FOR DENSE FOG. THEN THE
NEXT FORECAST CHALLENGE IS THE POSITION OF THE FRONTAL BOUNDARY BY
MAX HEATING THIS AFTERNOON. THE NAM IS IN LINE WITH OTHER MODELS
SHOWING THE BOUNDARY NEAR A SYRACUSE TO GARDEN CITY TO JUST NORTH
OF DODGE CITY TO A LACROSSE LINE BY 4 TO 7 PM. HAVE COOLED DAYTIME
HIGHS DOWN INTO THE LOW TO MID 70S NORTH OF THE FRONT WITH MID TO
UPPER 80S SOUTH. SOME HIGH LEVEL CIRRUS IS ALSO FORECAST TO MOVE
ACROSS WESTERN KANSAS INTO MID AFTERNOON WHICH MAY HELP TO HOLD
TEMPS DOWN FROM HITTING 90 ALONG OUR BORDER WITH OKLAHOMA. SOUTH
TO SOUTHWEST WINDS OF 15 TO 25 MPH WILL BE THE STRONGEST, WITH THE
DEEPEST MIXING, FROM JOHNSON CITY TO ULYSSES TO PRATT AND SOUTH TO
THE OKLAHOMA BORDER. A DRYLINE IS FORECAST TO PUSH EAST TO THE
AREA JUST EAST OF DODGE CITY TO ASHLAND THIS AFTERNOON THEN
RETREAT AGAIN TONIGHT.
FOR TONIGHT A STRONG UPPER LEVEL JET STREAK AND UPPER LEVEL
SHORTWAVE TROUGH WILL MOVE OUT OF THE COLORADO ROCKIES AND GREAT
BASIN AND INTO THE PLAINS. THIS SYSTEM WILL PUSH A STRONG COLD FRONT
ACROSS WESTERN KANSAS TONIGHT WITH NORTH WINDS INCREASING TO 25 TO
35 MPH AND GUSTY. WILL LET DAY SHIFT TAKE ANOTHER LOOK FOR A
POSSIBLE WIND ADVISORY. THE FRONT IS FORECAST TO MOVE THROUGH
HAYS BY 9 PM, THEN THROUGH GARDEN CITY AND DODGE CITY JUST BEFORE
MIDNIGHT AND FINALLY ACROSS MEDICINE LODGE BY 3 AM. THE MID LEVEL
COLD POOL IS FORECAST TO STAY JUST NORTH INTO NORTHERN KANSAS SO
THE CHANCES FOR PRE-FRONTAL THUNDERSTORMS LOOK LOW FOR TONIGHT.
HOWEVER JUST BEHIND THE FRONT THE MODELS ARE BREAKING OUT SOME
ELEVATED SHOWERS AND THUNDERSTORMS MAINLY IN THE WAKEENEY TO HAYS
AREA AND SOUTH TO LARNED AND MEDICINE LODGE. WILL MAINTAIN A 20-30
POP TO COVER. THE MAIN HAZARD WOULD BE LIGHTNING AS THE REGION OF
HIGHER CAPE SHIFTS EAST OF THE COLD FRONT. WITH GOOD MIXING
TONIGHT OUR OVERNIGHT LOWS SHOULD BE DOMINATED BY COLD AIR
ADVECTION AND NOT BY RADIATIONAL COOLING. SOME STRATUS WILL LIKELY
FOLLOW THE COLD FRONT WITH INCREASING CLOUDS INTO THE MORNING.
OVERNIGHT LOWS WILL BE IN THE UPPER 30S WEST AND NORTH TO THE MID
TO UPPER 40S SOUTHEAST FA FROM LARNED TO DODGE CITY AND ASHLAND
AND SOUTH.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 328 PM CDT TUE OCT 23 2012
THE FIRST PART OF THE EXTENDED PERIOD WILL BE CHARACTERIZED BY A
COUPLE OF FAST MOVING SHORTWAVE TROUGHS MOVING OUT OVER THE CENTRAL
AND NORTHERN PLAINS. THE FIRST ONE OF THESE WILL BE MOVING OUT OF
COLORADO ACROSS NEBRASKA AND NORTHERN KANSAS WEDNESDAY NIGHT INTO
EARLY THURSDAY. THIS SYSTEM WILL PUSH A STRONG COLD FRONT SOUTH
ACROSS WESTERN AND CENTRAL KANSAS WEDNESDAY NIGHT. THE MODELS SHOW
THAT THE UPPER LEVEL DYNAMICS WITH THIS WAVE WILL MOVE OVER NORTH
CENTRAL KANSAS DURING THE NIGHT. THE MODELS SPIT OUT SOME LIGHT QPF
OVER NORTHERN AND CENTRAL KANSAS. THE GFS MODEL APPEARS TO BE THE
MOST AGGRESSIVE WITH THIS AND HAS SOME LIGHT PRECIPITATION IN THE
HAYS/LACROSSE AREA DURING THE NIGHT. MODEL SOUNDINGS ARE NOT REAL
CONDUCIVE TO PRECIPITATION AS FAIRLY WARM AIR IN THE MID LEVELS WILL
BE OVER THE FRONTAL BOUNDARY LEADING TO STABLE CONDITIONS. THE GOING
FORECAST HAS SLIGHT CHANCE POPS IN THAT AREA SO WILL LEAVE IT AS IS
FOR NOW.
ANOTHER FAST MOVING SHORTWAVE TROUGH WILL FOLLOW THE FIRST ONE AND
SHOULD BE PASSING OVER WESTERN KANSAS BY FRIDAY MORNING. THERE WON`T
BE A LOT OF MOISTURE FOR THIS SYSTEM TO WORK WITH SO ONLY SOME MID
LEVEL CLOUDINESS IS EXPECTED. AT THE SURFACE, HIGH PRESSURE WILL BE
BUILDING SOUTH INTO THE CENTRAL HIGH PLAINS BEHIND THE FRONT. THE
CENTER OF THE HIGH SHOULD MOVE INTO WESTERN KANSAS OVERNIGHT FRIDAY
NIGHT. WITH THE DRY COOL IN PLACE AND GOOD RADIATIONAL COOLING
FRIDAY NIGHT, OVERNIGHT LOWS COULD PLUMMET WELL DOWN INTO THE MID
20S WITH A HARD FREEZE IN STORE FOR MUCH OF WESTERN KANSAS
BY THE END OF THE WEEKEND INTO EARLY NEXT WEEK WE SHOULD SEE WEST
NORTHWESTERLY FLOW ALOFT AND INCREASING HEIGHTS OVER THE WESTERN AND
CENTRAL UNITED STATES. THIS WILL ALLOW FOR A SLOW WARMING TREND BACK
INTO THE 60S AND LOWER 70S BY THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1224 AM CDT WED OCT 24 2012
A STRONG UPPER LEVEL JET AND ASSOCIATED UPPER LEVEL SHORTWAVE
TROUGH WILL MOVE INTO THE COLORADO ROCKIES BY LATE THIS AFTERNOON
THEN MOVE ACROSS THE PLAINS TONIGHT. THIS SYSTEM WILL FORCE A
STRONG COLD FRONT THROUGH WESTERN KANSAS TONIGHT. AHEAD OF THE
COLD FRONT EXPECT VFR CONDITIONS WITH SOUTH WINDS AROUND 10-15KT
THIS MORNING IN THE KGCK TO KDDC AREA AND LIGHT AND VARIABLE
AROUND KHYS. COULD HAVE SOME LOW STRATUS FOR A TIME IN THE KHYS
AREA BUT THERE IS SOME UNCERTAINTY. A SURFACE LOW AHEAD OF THE
COLD FRONT WILL MOVE INTO NEBRASKA WITH A WEAK FRONTAL BOUNDARY
THROUGH HAYS TO NEAR DODGE CITY AND GARDEN CITY. WINDS AT KGCK AND
KDDC MAY GO VARIABLE ALONG THIS BOUNDARY BY 13-16Z THIS MORNING.
THE STRONG COLD FRONT WILL THEN RAPIDLY SPILL SOUTHWARD ACROSS THE
TAF SITES AROUND 02Z AT KHYS, O4Z AT KGCK, AND 05Z AT KDDC AS A
FIRST GUESS OF THE NAM12. WINDS BEHIND THE COLD FRONT WILL
INCREASE RAPIDLY TO 20-35KT WITH CIGS LOWERING TO MVFR. THERE
COULD ALSO BE AN ELEVATED THUNDERSTORM IN THE KHYS AREA BETWEEN
02-06Z.
&&
.FIRE WEATHER...
ISSUED AT 328 AM CDT WED OCT 24 2012
WILL KEEP A RED FLAG WARNING FOR STANTON, GRANT, MORTON, AND
STEVENS COUNTIES THIS AFTERNOON WITH POSSIBLE MIXDOWN WINDS NEAR
25 TO 30 MPH FROM THE SOUTH TO SOUTHWEST AND RELATIVE HUMIDITIES
BELOW 15 PERCENT. THE OTHER COUNTIES OF HAMILTON TO FINNEY AND
SOUTH TO HASKELL AND SEWARD COUNTIES THAT WERE IN A FIRE WEATHER
WATCH WILL GO AHEAD AND CANCEL FOR LESS WINDS AND HIGHER RELATIVE
HUMIDITIES.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 85 43 53 30 / 0 10 10 10
GCK 79 39 52 29 / 0 10 10 10
EHA 87 39 52 28 / 0 10 10 10
LBL 87 40 53 29 / 0 10 10 10
HYS 73 40 52 29 / 0 30 10 10
P28 87 50 56 34 / 0 20 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR KSZ030-031-
043>046.
RED FLAG WARNING FROM 1 PM THIS AFTERNOON TO 7 PM CDT THIS
EVENING FOR KSZ074-075-084-085.
&&
$$
SHORT TERM...KRUSE
LONG TERM...GERARD
AVIATION...KRUSE
FIRE WEATHER...KRUSE
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
838 AM EDT WED OCT 24 2012
.SYNOPSIS...
ISOLATED LIGHT SHOWERS CAN BE EXPECTED THIS MORNING AS AN UPPER
DISTURBANCE CROSSES THE UPPER OHIO VALLEY REGION. OTHERWISE...WARM
AND DRY WEATHER WILL CONTINUE UNTIL THE APPROACH AND PASSAGE OF A
STRONG COLD FRONT THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A QUICK UPDATE HAS BEEN ISSUED THIS MORNING TO REDUCE THE COVERAGE
OF SHOWERS TO ISOLATED EARLY TODAY AS A WEAK SHORT WAVE SHIFTS
SOUTHEAST OF THE AREA.
THE LATEST RAP MID-LEVEL ANALYSIS INDICATES A SHORT WAVE SLIDING
SOUTHEASTWARD ACROSS WESTERN PA. A WARM FRONT REMAINS NORTH OF THE
AREA WITH A WARM SOUTHWESTERLY FLOW ACROSS THE FORECAST AREA. A
WARM DAY IS IN STORE WITH THE 12Z KPIT SOUNDING 850 TEMP AT 11C.
SURFACE TEMPS ARE RANGING FROM THE MID 50S TO LOWER 60S ALREADY
THIS MORNING.
THE SHORT WAVE WILL SLIDE SOUTHEAST OF THE FORECAST AREA
TODAY...WITH ISOLATED SHOWERS MOSTLY COMING TO AN END THIS
MORNING. ISOLATED SHOWERS ARE FORECAST TO LINGER THE LONGEST ALONG
THE I-80 CORRIDOR WITH ITS CLOSER PROXIMITY TO THE WARM FRONT.
MID-LEVEL MOISTURE WILL SHIFT EAST OF THE AREA WITH THE WAVE AND
BREAKS IN CLOUD COVERAGE CAN BE EXPECTED THIS AFTERNOON. WEAK
WARM AIR ADVECTION WILL CONTINUE TODAY AS A THERMAL RIDGE BUILDS
IN FROM THE WEST AND 850 TEMPS WARM TO 12-14C BY 00Z. WITH WAA AND
MORE BREAKS IN CLOUD COVERAGE IN MIND...FORECAST TEMPS TODAY ARE
AROUND A DEGREE WARMER THAN LAMP GUIDANCE. HIGHS TODAY WILL BE
AROUND 15 DEGREES ABOVE NORMAL FOR THIS DATE...RANGING FROM THE
LOWER 70S ACROSS THE EASTERN RIDGES TO THE UPPER 70S IN EASTERN
OHIO.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
BUILDING SHORTWAVE RIDGE IN THE WAKE OF THE AFTERNOON DISTURBANCE
WILL SNUFF ANY RESIDUAL SHOWERS BY THIS EVE...WITH WARM ADVECTION
PREVENTING A SIGNIFICANT TEMPERATURE DROP OVERNIGHT. THAT REGIME
IS EXPECTED TO RESULT IN A TEMPERATURE PROFILE THAT MAY SUPPORT
NEAR 80F TEMPERATURES AT SOME LOCATIONS ON THURSDAY.
ANOTHER WARM DAY IS FORECAST FOR FRIDAY...BUT FALLING HEIGHTS
ALOFT AND INCREASED CLOUD COVER IN THE AFTERNOON...ALL IN
RESPONSE TO THE APPROACH OF A STRONG COLD FRONT...SHOULD KEEP
TEMPERATURE READINGS A FEW DEGREES UNDER THE THURSDAY NUMBERS.
ALTHOUGH SLIGHT...TO CHANCE POP NUMBERS WERE MAINTAINED ON FRIDAY
AFTERNOON...CURRENT TIMING OF FRONT-PROGRESS SUGGESTS THE BETTER
CHANCE FOR PRECIP WILL BE FRIDAY NIGHT AND SATURDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
POPS FOR SHOWERS WERE GRADUALLY ESCALATED TO LIKELY NUMBERS FOR
THE ACTUAL FRONTAL ENCROACHMENT...CURRENTLY FORECAST FOR SATURDAY.
THEREAFTER...CONFIDENCE IN THE FORECAST FALTERS AS MODELS ARE NOT
IN AGREEMENT IN RESOLUTIONS OF THE COASTAL TROPICAL SYSTEM AND
INTERACTION WITH THE NORTHERN STREAM TROUGH/COLD FRONT.
FORECAST IS THUS BASED ON THE ENSEMBLE MEAN AND IS OF CHANCE POPS
IN THE IMMEDIATE WAKE OF THE FRONT ACCOMPANIED BY MUCH COLDER
TEMPERATURES...WHICH MAY SUPPORT SNOW SHOWERS ON THE RIDGES BY
EARLY MONDAY. COLD ADVECTION UNDER THE DEVELOPING EASTERN CONUS
TROUGH IS EXPECTED TO RESULT IN READINGS TO ABOUT 15 DEGREES BELOW
NORMAL BY TUESDAY.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS ARE FORECAST THROUGH THE PERIOD WITH ANY LINGERING
ISOLATED SHOWERS DIMINISHING THIS AFTERNOON AS A MID-LEVEL
DISTURBANCE SHIFTS EAST OF THE AREA.
CLOUD COVERAGE WILL DECREASE FROM THE WEST LATE THIS MORNING INTO
THE EARLY AFTERNOON AT ALL PORTS. WINDS WILL BE SOUTHERLY
TODAY...INCREASING TO AROUND 10KTS WITH GUSTS TO 20KTS THIS
AFTERNOON...AND THEN DIMINISHING TO NEAR CALM TONIGHT.
.OUTLOOK.../THURSDAY THROUGH SUNDAY/...
VFR CONDITIONS WILL CONTINUE TO PREVAIL UNTIL SATURDAY WHEN A COLD
FRONT APPROACHES FROM THE WEST AND RETURN SHOWERS WITH RESTRICTIONS.
CEILING RESTRICTIONS WILL BE POSSIBLE IN THE WAKE OF THE FRONT ON
SATURDAY NIGHT INTO SUNDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
417 PM EDT WED OCT 24 2012
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 416 PM EDT WED OCT 24 2012
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW SW FLOW ALF OVER
THE PLAINS BTWN DEEP TROF OFF THE PACIFIC COAST AND AN UPR RDG AXIS
ALIGNED FM HUDSON BAY THRU THE CENTRAL GRT LKS INTO THE SE CONUS.
DESPITE THE PRESENCE OF AN UNSEASONABLY WARM...MOIST LLVL AIRMASS
/PWATS UP TO 250 PCT OF NORMAL/ OVER THE UPR GRT LKS...THERE ARE
ONLY A FEW -SHRA NOTED ON THE MQT RADAR DUE TO STRONG CAPPING INVRN
BTWN H75-8 AS NOTED ON THE LOCAL 12Z RAOBS EVEN THOUGH A SHALLOW...
WEAK COLD FNT ATTENDANT TO CLOSED LO OVER SASKATCHEWAN HAS LIMPED
INTO THE FAR WRN CWA. A DISTURBANCE WITH 70KT H5 WINDS LIFTING NEWD
THRU THE DAKOTAS IS CAUSING AN AREA OF -SHRA UNDER SHARP H7 TEMP
GRADIENT OVER THE NRN PLAINS INTO NW MN WELL WELL W OF THE SFC COLD
FNT AND THE AREA INFLUENCED BY THE SHARP MID LVL CAP. THE SHRTWV IN
THE NRN PLAINS AND ANOTHER MORE VIGOROUS DISTURBANCE MOVING THRU THE
CNTRL ROCKIES HAVE CONSPIRED TO CAUSE A LO PRES TO DVLP FARTHER S ON
THE COLD FNT IN KANSAS. OVER UPR MI... AREAS OF FOG LINGER
ESPECIALLY OVER THE CENTRAL ZNS WHERE LLVL SSE FLOW IS UPSLOPING.
THE LOWERING SUN ANGLE AND PERSISTENT FOG AND LO CLDS HAVE LIMITED
SFC WARMING. FARTHER TO THE S...MORE BREAKS IN THE LO CLDS HAVE
ALLOWED FOR MORE SFC WARMING OVER ERN IOWA AND SRN WI.
TNGT...MAIN FCST CONCERNS ARE SHRA/TS CHCS AND POTENTIAL FOR SVR WX
AS DISTURBANCES LIFT TO THE NE OUT OF MEAN WRN TROF. SPC HAS PLACED
WRN UPR MI IN A SLGT RISK FOR SVR STORMS TNGT. GIVEN ABSENCE OF ANY
SGNFT SFC WARMING OVER UPR MI THIS AFTN AND SHARP INVRN...ANY
CONVECTION SHUD BE ELEVATED AND DEPENDENT ON WHETHER/HOW QUICKLY THE
SHARP H8-75 INVRN WEAKENS. 12Z GFS/NAM HAVE TRENDED TO SHIFT FOCUS
FOR MOST SGNFT DEEP LYR QVECTOR CNVGC ASSOCIATED WITH DISTURBANCE
NOW IN THE NRN PLAINS INTO MN AT 00Z...A LOGICAL SHIFT GIVEN HI
AMPLITUDE PATTERN IN PLACE AND SHIFT OF SECOND SHRTWV FARTHER W INTO
THE UPR TROF AXIS. HIER RES NAM RUN SHOWS THE SHARPEST/SLOPED H85-7
FGEN/UVV IMPACTING WRN LK SUP AT 00Z BEFORE SHIFTING TO THE NE AS
THE DEEP LYR QVECTOR CNVGC ASSOCIATED WITH THE FIRST SHRTWV FADES AS
THE UPR TROF DEEPENS FARTHER W WITH CLOSER APRCH OF 2ND SHRTWV.
GIVEN THE STRENTH OF THE CAPPING ILLUSTRATED BY THE 12Z RAOBS...
SUSPECT MOST WDSPRD AND INTENSE SHRA/TS THIS EVNG WL MISS THE LAND
CWA TO THE W...WITH ALL BUT THE FAR W SEEING NOTHING MORE THAN
ISOLD-SCT -SHRA/TS OR -DZ IN THIS SCENARIO AS WEAKER FORCING HERE
LIMITS THE WEAKENING OF THE CAP. EVEN THE NAM DOES SHOW A SECOND
AREA OF HIER QPF OVER THE SE ZNS...AND THIS MIGHT DEPEND ON IF SOME
SHRA DVLP WITH THE CLRG OVER SE WI AND MOVE TO THE N. ALTHOUGH THE
GFS SHOWS SIMILAR UPR FORCING...THIS MODEL...WITH THE SUPPORT OF THE
12Z CNDN GEM MODEL...SHOWS AXIS OF HIER QPF OVER WRN UPR MI NEAR THE
SFC COLD FNT. GIVEN THE PLACEMENT OF THE SHARPER DYNAMICS AND
PATTERN RECOGNITION... THINK THE NAM FCST IS THE BEST BET. GIVEN
IMPRESSIVE DEEP LYR SHEAR ABV THE MORE STABLE LYR NEAR THE SFC...ANY
TS THAT MIGHT IMPACT THE WRN ZNS COULD TURN SVR WITH HAIL THE MAIN
THREAT GIVEN SFC BASED STABILITY. WITH THE UNSEASONABLY WARM...MOIST
AIRMASS IN PLACE AND HI FRZG LVL...ANY SHRA COULD DUMP HEAVY RA EVEN
IF THEY ARE FAST MOVING UNDER THE STEADY FLOW ALF. AS THE SECOND
SHRTWV RIDES NEWD LATER TNGT...ANOTHER AREA OF VIGOROUS H85-5
QVECTOR CNVGC/UPR DVGC IS PROGGED TO IMPACT MAINLY MN TOWARD 12Z. SO
AFT INITIAL ROUND OF HIER POPS LIFTS TO THE NE...SUSPECT ANOTHER
ROUND OF HEAVIER SHRA/SOME TS WL INVADE THE WRN CWA LATER. WITH ONLY
MODEST DIURNAL COOLING...EXPECT FOG TO REDVLP... ESPECIALLY IN AREAS
OVER THE ECNTRL EXPERIENCING UPSLOPE SSE WINDS.
THU...AS DISTURBANCE/ACCOMPANYING H3 JET MAX AND DEEP LYR QVECTOR
CNVGC/UPR DVGC RIDE TO THE NNE WITH ASSOCIATED SFC LO MOVING UP THE
STALLED COLD FNT OVER THE W...EXPECT AN AREA OF SHRA/EMBEDDED TS TO
IMPACT MAINLY THE W HALF IN THE MRNG BEFORE THE SHRTWV MOVES FAR
ENUF TO THE N AND DEEP LYR QVECTOR DVGC DVLPS WITH DNVA/STRONG CAD
IN THE WAKE OF COLD FROPA AS SFC LO MOVES INTO ONTARIO IN THE AFTN.
THINK CATEGORICAL POPS ARE APPROPRIATE OVER THE W IN THE MRNG...WITH
THE HIER POPS FOLLOWING THE COLD FROPA TO THE E. ALTHOUGH SFC BASED
STABILITY WL LIMIT THE INCRS IN WIND SPEED BLO ADVY LVL...S WINDS
NEAR LK MI MAY BECOME QUITE GUSTY IN ADVANCE OF THE COLD FROPA UNDER
H925 WINDS UP TO 50 KTS AND WITH SHARP PRES FALL CENTER MOVING INTO
ONTARIO AHEAD OF THE SFC LO PROVIDING ENHANCEMENT TO THE S GRADIENT
FLOW. COMBINATION OF STRONG CAD AND W H925 WINDS INCRSG UP TO 35-40
KT IN THE WAKE OF THE FROPA MIGHT CAUSE WIND GUSTS OVER THE EXPOSED
KEWEENAW TO AT LEAST APRCH ADVY LVL IN THE AFTN. ENUF COLD AIR MAY
ARRIVE TO AT LEAST MIX LINGERING USPLOPE LK ENHANCED -SHRA WITH SN
OVER THE FAR W IF THE COLDER NAM SHOWING H85 TEMPS FALLING TOWARD
-5C AT 00Z FRI VERIFIES. THE SHARP COLD FROPA WARRANTS A NON DIURNAL
TEMP TREND...WITH TEMPS FALLING BEHIND THE FROPA ESPECIALLY OVER THE
W.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 416 PM EDT WED OCT 24 2012
BY EARLY THURSDAY EVENING...THE MAIN SFC LOW SHOULD BE OVER NE
ONTARIO...WITH THE COLD FRONT JUST E OF UPPER MI...AND A SECONDARY
TROUGH SET UP E-W FROM THE LOW ACROSS LAKE WINNIPEG. THE 500MB LOW
OVER LAKE WINNIPEG WILL SLIDE NNE OUT OF THE AREA.
W FLOW AND 850MB TEMPS AROUND -8C SHOULD HELP KEEP SOME LAKE
ENHANCED SHOWER ACTIVITY GOING ACROSS W UPPER MI. HOWEVER...THE LOW
LEVEL MOISTURE WILL BE QUITE A BIT LESS DURING THAT TIME...WITH
PLENTY OF CLOUDS BUT JUST LIGHT SNOW SHOWERS OR FLURRIES POSSIBLE.
EXPECT THE SECONDARY TROUGH TO PUSH ACROSS THE KEWEENAW PENINSULA
FRIDAY EVENING...BUT HAVE LITTLE WITH IT AS MUCH OF THE ENERGY
REMAINS CLOSER TO THE SFC LOW ITSELT OVER N HUDSON BAY BY THAT TIME.
ANOTHER ROUND OF CLOUDS AND LIGHT SNOW SHOWERS. NO SIGNIFICANT
ACCUMULATION IS EXPECTED...AS THE BEST SNOW GROWTH REGION /AOA
800MB/ REMAINS WELL ABOVE THE MOISTURE.
THE LARGE SCALE TROUGH WILL DOMINATE MUCH OF THE NATION FRIDAY NIGHT
THROUGH AT LEAST SATURDAY. AN ELONGATED AREA OF HIGH PRESSURE
STRETCHING FROM THE MAIN HIGH OVER CENTRAL CANADA TO THE CENTRAL
PLAINS FRIDAY NIGHT WILL SLOWLY BUILD ACROSS THE UPPER GREAT
LAKES...THROUGH AT LEAST SUNDAY.
HIGH PRESSURE WILL REMAIN STRONG OVER ONTARIO THROUGH THE MID MS
VALLEY...EVEN AS THE STRONG SYSTEM PUSHES TOWARDS THE EAST COAST. AS
A RESULT OF THE NEARING STORM SYSTEM...THE SFC HIGH SHOULD MAINTAIN
ITS INFLUENCE OVER THE W HALF OF UPPER MI. HOWEVER...N FLOW WILL
LIKELY DOMINATE FAR E UPPER MI FROM SUNDAY NIGHT THROUGH THE END OF
THE FCST PERIOD /WEDNESDAY/ AS THE LOW RETROGRADES .
UNLIKE THE ECMWF WHICH CONTINUES TO SHOW GOOD RUN TO RUN CONSISTANCY
ON THE POTENTIAL STORM SYSTEM SLIDING TOWARDS THE E COAST...THE GFS
IS A BIT MORE JUMPY. THE MODEL IS SPLIT ON WHETHER TO BRING THE LOW
OFF TO SEE...OR EVEM MORE ONSHORE BY WEDNESDAY MORNING /NEAR LAKE
HURON/ IF THE 24/06Z RUN IS CORRECT. THE 24/12Z GFS SHIFTED THE
500MB LOW APPROX 300-350MI W OF ITS PREVIOUS MORE OUT TO SEA
LOCATION MONDAY MORNING. WILL CONTINUE TO HEDGE THE FCST A BIT
CLOSER TO THE MORE STABLE ECMWF SOLUTION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 204 PM EDT WED OCT 24 2012
QUITE A PESSIMISTIC FORECAST IN THE MAKING AS ABUNDANT MOISTURE AND
AN OVERALL STAGNANT AIRMASS ALONG A SURFACE BOUNDARY WILL KEEP CIGS
AND VIS QUITE LOW AT ALL SITES THROUGH MUCH OF THE TAF PERIOD. A
SURFACE BOUNDARY SLOWLY MOVING EASTWARD HAS JUST PASSED THROUGH IWD.
GIVEN GENERAL FLOW FROM THE NE...HAVE LOWERED CIGS AND VIS
THROUGHOUT THE REMAINDER OF THE AFTERNOON. RECENT OBS WITH VIS
M1/4SM HAVE LED TO SOME CONCERN THAT VIS/CIGS MAY END UP EVEN LOWER
THAN FORECAST...SO THIS WILL BE MONITORED CLOSELY. DO NOT EXPECT
MUCH IMPROVEMENT AT IWD WITH FLOW OUT OF THE NORTH TO NE THROUGH
EARLY THURSDAY MORNING.
AS FOR CMX...THE BOUNDARY IS EXPECTED TO EASE ACROSS THE KEWEENAW
OVERNIGHT. UPSLOPE INFLUENCE SHOULD DECREASE AS FLOW BECOMES MORE
NORTHERLY INSTEAD OF NORTHEASTERLY...SO A GRADUAL IMPROVEMENT IN VIS
AND CIGS SHOULD OCCUR. A SECONDARY...STRONG COLD FRONT SHOULD REACH
CMX BY 18Z THURSDAY...WITH A QUICK WIND SHIFT TO THE WNW AND WIND
SPEED INCREASE WELL ABOVE 12KTS.
SSE UPSLOPE FLOW AT SAW IS KEEPING CIGS BELOW LANDING MINS THIS
AFTERNOON. THE WINDOW FOR CIGS TO RISE AT OR ABOVE LANDING MINS IS
DWINDLING AS SUNSET APPROACHES. HAVE THUS KEPT CIGS AT OR BELOW
LANDING MINS THROUGH TONIGHT UNTIL WINDS SHIFT MORE TO THE SSW AND
REDUCE UPSLOPE FLOW AHEAD OF THE APPROACHING COLD FRONT.
LASTLY...MARGINAL LLWS OF ABOUT 30-40KTS OVER THE LOWEST 1.5KFT IS
POSSIBLE AS WINDS ALOFT INCREASE AHEAD OF THE FRONT
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 416 PM EDT WED OCT 24 2012
EXPECT DENSE FOG OVER THE W HALF OF LAKE SUPERIOR TO LINGER THRU
THIS EVENING BEFORE THE ARRIVAL OF SOMEWHAT DRIER LOW LEVEL AIR IS
ABLE TO DISSIPATE THE FOG. THE DENSER FOG WILL LINGER LONGEST NEAR
THE W SHORE OF UPPER MI. OTHERWISE...EXPECT S WINDS TO INCREASE TO
30 KTS OVER THE E HALF OF THE LAKE ON THU AS A STRONG COLD FRONT
APPROACHES. RELATIVELY LIGHT WINDS OVER THE W AND CENTRAL WILL SHIFT
TO THE W FOLLOWING THE COLD FROPA ON THU AND INCREASE UP TO 30 KTS
IN THE AFTERNOON...WITH HIGH PRESSURE DEVELOPING OVER THE NORTHERN
AND CENTRAL PLAINS. THERE MAY BE SOME GALE FORCE WINDS NEAR THE KEWEENAW
LATE IN THE DAY. THESE MARGINAL GALES WILL LIKELY IMPACT PORTIONS OF
THE CENTRAL LAKE ON THU EVENING...SO HOISTED A GALE WATCH FOR NOW IN
THIS AREA. LIGHTER WINDS WITH HIGH PRESSURE WILL SLOWLY PUSH OVER
THE UPPER GREAT LAKES THROUGH MONDAY...WITH THE STRONGEST WINDS OVER
E LAKE SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM THURSDAY EVENING THROUGH LATE THURSDAY NIGHT FOR
LSZ265-266.
DENSE FOG ADVISORY UNTIL 11 PM EDT /10 PM CDT/ THIS EVENING FOR
LSZ162-263-264.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL 6 PM EDT THIS EVENING FOR LMZ221-250.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...TK
MARINE...KC/KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
140 AM EDT WED OCT 24 2012
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 447 PM EDT TUE OCT 23 2012
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW SW FLOW ALF OVER
THE CENTRAL CONUS BTWN DEEP TROF ALONG THE PACIFIC COAST AND UPR RDG
OVER ERN NAMERICA. THERE IS AN AREA OF SHRA/SOME TS OVER MAINLY THE
WRN CWA ASSOCIATED WITH A DISTURBANCE MOVING NEWD TO THE N OF H85
WARM FNT STRETCHING FM THE NRN PLAINS INTO THE UPR MIDWEST AND
ACCOMPANYING SHARPER H85-5 QVECTOR CNVGC/ISENTROPIC ASCENT BEST
SHOWN ON THE 300K SFC IN THE PRESENCE OF STEEP H85-5 LAPSE RATES
SHOWN ON THE 12Z MPX RAOB. SMALL HAIL FELL FM A FEW OF THE STRONGER
CELLS OVER THE WRN CWA/NW WI EARLIER. THE E HALF OF THE CWA HAS BEEN
MAINLY PCPN FREE WITH A DRIER/MORE STABLE PROFILE SHOWN ON THE 12Z
APX RAOB. EXCEPT FOR A CLUSTER OF SHRA/EMBEDDED TS OVER SCNTRL
WI...AREAS TO THE SW OF H85 WARM FNT ARE GENERALLY DRY WITH STRONG
CAP SHOWN ON THE 12Z ABERDEEN SDAKOTA RAOB DOMINATING. HOWEVER...
THERE IS QUITE A BIT OF LO CLD AND FOG WITH ABUNDANT LLVL MSTR/SFC
DEWPTS AN UNSEASONABLY HI 55 TO 60.
LATE THIS AFTN...AS AREA OF SHARPER ISENTROPIC ASCENT/DEEP LYR
QVECTOR CNVGC SUPPORTING THE NMRS SHRA/ISOLD TS OVER THE WRN CWA
EARLY THIS AFTN SHIFTS TO THE N...EXPECT DIMINISHING POPS S-N OVER
THE W. WITH ABSENCE OF UPR SUPPORT FOR PCPN OVER THE E HALF...
EXPECT ONLY ISOLD-SCT -SHRA IN THIS AREA. THE ONLY EXCEPTION MIGHT
BE THE SCNTRL...WHERE AREA OF SHRA NOW OVER WI AND DRIFTING TO THE
NE WILL BRUSH THE AREA.
TONIGHT...AS MAIN SHRTWV IN THE NRN PLAINS MOVG NEWD WELL TO THE W
LIFTS INTO SCNTRL CAN...UPR HGTS ARE FCST TO RISE SLOWLY OVER THE
CWA WITH AREA OF DEEP LYR QVECTOR CNVGC LIFTING TO THE N AND AWAY FM
UPR MI. WITH LACK OF DYANMIC SUPPORT AND FCST SDNGS HINTING AT MID
LVL DRYING/CAPPING AS SHOWN ON THE ABERDEEN RAOB...SUSPECT THERE WL
BE NOTHING MORE THAN ISOLD-SCT -SHRA WITH THE GREATER POPS THIS EVNG
OVER THE KEWEENAW INTO NCNTRL LK SUP. OTRW...INFLUX OF LLVL MSTR
WITH FLOW VEERING MORE TO THE S WL SUPPORT AREAS OF FOG...
ESPECIALLY OVER THE CNTRL CWA WITH UPSLOPE SE VEERING S FLOW. FOG IN
THIS AREA MIGHT BECOME DENSE. EXPECT LTL DIURNAL FALL OF TEMP WITH
INFLUX OF LLVL MSTR.
WED...COLD FNT ATTENDANT TO SHRTWV LIFTING TO THE NE THRU CNTRL
CANADA WL LIMP INTO THE WRN ZNS IN THE MRNG. SINCE THERE WL BE LTL
IN THE WAY OF LARGE SCALE FORCING AT THAT TIME...EXPECT NOTHING MORE
THAN SCT -SHRA TO ACCOMPANY ITS ARRIVAL. HOWEVER...APRCH OF MORE
SGNFT SHRTWV LIFTING OUT OF WRN TROF IN THE AFTN WL SUPPORT HIER
POPS THERE IN THE AFTN...WITH LOWER POPS TO THE E TOWARD HIER H5
HGTS AND AWAY FM INCOMING DEEP LYR QVECTOR CVNGC/FGEN/MSTR CNVGC
ALONG BNDRY. STEEP H7-5 LAPSE RATES SUPPORT MENTION OF TS. AREAS OF
FOG WL LIKELY PERSIST MUCH OF THE DAY UNDER CONSIDERABLE CLD
COVER...ESPECIALLY OVER THE CNTRL WITH PERSISTENT UPSLOPE LLVL FLOW.
ALTHOUGH TEMPS WL BE WELL ABV NORMAL...TENDED TO LOWER GOING FCST
MAX TEMPS A BIT TO ACCOUNT FOR EXPECTED FOG/CLD COVER.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 447 PM EDT TUE OCT 23 2012
THE 500MB RIDGE WILL BE JUST TO OUR EAST /STRETCHING THROUGH THE
LOWER GREAT LAKES AND HUDSON BAY...WITH A WELL FORECASTED LOW
PUSHING IN FROM CENTRAL CANADA. SW FLOW ALOFT WILL REMAIN OVERHEAD
THROUGH SATURDAY NIGHT AS THE 500MB LOW SHIFTS FROM AROUND LAKE
WINNIPEG AT 00Z FRIDAY TO S HUDSON BAY FRIDAY...BEFORE EJECTING N
SATURDAY.
THE BEST CHANCE OF SHOWERS THROUGH THE ENTIRE EXTENDED LOOKS TO BE
WEDNESDAY NIGHT...THEN PUSHING W TO E DURING THE DAY THURSDAY AS THE
ELONGATED SFC LOW STRETCHING FROM THE KEWEENAW THROUGH N TX AT 06Z
THURSDAY DEEPENS SLIGHTLY AS IT PUSHES ACROSS LAKE SUPERIOR DURING
THE AFTERNOON HOURS...AND INTO NE ONTARIO BY 00Z FRIDAY. A FEW
THUNDERSTORMS WILL BE POSSIBLE MAINLY OVER THE W HALF WEDNESDAY
NIGHT...THEN CENTRAL AND E THURSDAY. THE SWATH OF HEAVIEST RAIN
/OVER AN INCH FROM WEDNESDAY EVENING THROUGH THURSDAY EVENING/ LOOKS
TO HAVE SHIFTED SLIGHTLY WESTWARD. THIS INCLUDES AREAS FROM IWD
THROUGH CRYSTAL FALLS...AND N THROUGH THE KEWEENAW PENINSULA. THE
FAR EAST THIRD OF THE CWA MAY BE LUCKY TO RECEIVE HALF AN INCH BY
THE TIME IT IS DONE. A FEW SNOWFLAKES COULD MIX IN OVER INTERIOR W
LOCATIONS THURSDAY NIGHT AS COLD AIR WRAPS IN.
THE 23/00Z CANADIAN BRINGS A SECONDARY WAVE THAT LINGERED OVER LAKE
WINNIPEG AT 06Z FRIDAY...SLOWLY PUSHING IT TO JUST NW OF LAKE
SUPERIOR BY DAYBREAK SATURDAY...AND STILL JUST N OF THE LAKE SUNDAY
AFTERNOON. WHILE A TROUGH WILL LIKELY RESIDE NEAR LAKE SUPERIOR
THROUGH MUCH OF THIS TIME PERIOD...THE CANADIAN LOOKS TO BE A BIT
TOO STRONG/DEEP WITH THE FEATURE /AT LEAST A LITTLE TOO EARLY/. AS A
RESULT...WITH LEAN CLOSER TO THE ECMWF...AND UTILIZE A LITTLE LESS
OF THE CANADIAN OUTPUT FROM FRIDAY AFTERNOON ON.
THE 500MB TROUGH WILL LINGER OVERHEAD FROM SATURDAY THROUGH AT LEAST
SUNDAY NIGHT...AS A SFC HIGH PUSHES IN FROM THE W. BY SUNDAY NIGHT
THE GFS AND ECMWF SPLIT WAYS...ESPECIALLY WITH THE HANDLING OF THE
SYSTEM OFF THE EAST COAST. A MIX OF RAIN AND MOSTLY SNOW WILL BE
POSSIBLE SATURDAY...WITH ONSHORE ENHANCEMENT SATURDAY NIGHT OVER
THE KEWEENAW PENINSULA AS 850MB TEMPS COOL TO AROUND -9C. LOOKING AT
THE FCST MODELS CLOSER TO HOME THE GFS REMAINS MORE PROGRESSIVE...AS
AN ADDITIONAL 500MB LOW NEARS FROM S CENTRAL CANADA MONDAY NIGHT.
THE RESULT WOULD BE BRIEF RIDGING OVER THE UPPER GREAT LAKES MONDAY.
THE ECMWF ON THE OTHER HAND SINKS/WRAPS UP A LOW OVER THE OHIO
VALLEY. WILL NOT GET TOO SPECIFIC...BUT WILL LIMIT THE QUICKER
INFLUENCE OF THE NORTHERN LOW NEARING THE CWA ON DAY 6/7.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 139 AM EDT WED OCT 24 2012
WITH A VERY MOIST AIR MASS ADVECTING N...IFR/LIFR CONDITIONS WILL
GENERALLY PREVAIL THRU THE FCST PERIOD AT KIWD/KCMX/KSAW. FAVORABLE
SE-S UPSLOPE WIND SHOULD LEAD TO LIFR PREVAILING AT KSAW THRU THE
MORNING. AT KCMX...AS WINDS VEER MORE TO THE SE OR S OVERNIGHT...
DOWNSLOPING OFF THE HURON MTNS SHOULD LEAD TO CIGS AT KCMX RISING TO
MVFR FOR A TIME OVERNIGHT. LIKEWISE...COULD SEE CIGS AT KIWD ALSO
RISE TO MVFR AT TIMES OVERNIGHT DUE TO DOWNSLOPE COMPONENT TO WIND.
WEAKENING WINDS WITH ARRIVAL OF LOW PRES TROF THIS MORNING SHOULD
RESULT IN LIFR CIGS AGAIN SETTING IN AT KIWD/KCMX. DEVELOPING WAVE
OF LOW PRES LIFTING N ALONG TROF WILL BRING SHRA INTO THE AREA LATER
IN THIS FCST PERIOD...PROLONGING IFR/LIFR CONDITIONS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 447 PM EDT TUE OCT 23 2012
EXPECT E WINDS UP TO 30 KTS THIS EVENING...WITH A FEW GALE FORCE
GUSTS TO 35 KTS WHERE TERRAIN ENHANCES THESE WINDS OVER THE
NCENTRAL. ALTHOUGH THE STRONGER SE FLOW WILL PERSIST OVER THE E HALF
OVERNIGHT...THE WINDS WILL DIMINISH OVER THE W AFTER MIDNIGHT AS
SHARPER PRES GRADIENT SHIFTS TO THE NE IN ADVANCE OF AN APPROACHING
COLD FRONT. THIS WEAKER PRES GRADIENT WILL OVERSPREAD THE ENTIRE
LAKE ON WED...RESULTING IN DIMINISHING WINDS EVEN OVER THE E HALF.
SOME FOG IS LIKELY TO DEVELOP OVER THE W FOLLOWING THE COLD FROPA. A
NEW LOW WILL ORGANIZE ACROSS THE CENTRAL PLAINS WEDNESDAY AND LIFT
NORTHEASTWARD ACROSS LAKE SUPERIOR THURSDAY...WITH A FEW GALE FORCE
GUSTS OF 35KTS POSSIBLE OVER MAINLY CENTRAL LAKE SUPERIOR THURSDAY
NIGHT. A RIDGE OF HIGH PRESSURE WILL THEN BUILD INTO THE REGION
FRIDAY THROUGH SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
927 PM CDT THU OCT 25 2012
.UPDATE...
ISSUED AT 851 PM CDT THU OCT 25 2012
COLD FRONT HAS PUSHED SE OF OUR FORECAST AREA EARLY THIS EVNG.
POST FRONTAL BAND OF SHOWERS AND A FEW THUNDERSTORMS HAS
TRANSLATED EWD INTO SERN MO AND SWRN IL...MAINLY FROM STL S AND
E. THIS BAND OF PRECIPITATION WAS IN A REGION OF 850 MB MOISTURE
CONVERGENCE ALONG THE 850 MB FRONT...AND APPEARED TO BE SHIFTING
EWD A LITTLE FASTER THAN THE MODELS HAD FORECAST WHICH WILL LIKELY
LEAD TO A QUICKER ENDING OF THE RAIN TGT. SLOWED THE CLEARING OF
THE CLOUD COVER LATE TGT AND SAT WITH PLENTY OF LOW LEVEL
CLOUDINESS ACROSS ERN NEBRASKA AND IA WHICH WILL ADVECT SEWD
THROUGH OUR AREA. THERE MAY BE SOME BREAKS OR HOLES IN THE
OVERCAST BUT THESE SHOULD BE SHORT LIVED. THE RUC OR RAP MODEL
SEEMS TO HAVE THE BEST HANDLE ON THE CLOUD FORECAST. WITH CLOUDY
SKIES CONTINUING THROUGH THE NIGHT ALONG WITH STRONG AND GUSTY
NWLY SFC WINDS THE LOW TEMPERATURES MAY NOT BE QUITE AS COLD AS
PREVIOUSLY THOUGHT...ALTHOUGH STILL WELL BELOW NORMAL DUE TO THE
STRONG CAA TGT.
GKS
&&
.SHORT TERM...
ISSUED AT 239 PM CDT THU OCT 25 2012
(TONIGHT)
A STRONG COLD FRONT WILL CONTINUE MOVING SEWD THROUGH THE CWA
TONIGHT WITH POSTFRONTAL SHRA SPREADING ACROSS THE AREA. PCPN
COVERAGE SHOULD DIMINISH OVER MOST OF THE AREA AFTER 06Z BASED ON
MODEL FCSTS OF FRONTOGENETICAL FORCING FROM THE SFC THROUGH 700MB.
AN ISOLATED THUNDERSTORM ALONG THE SLOPED FRONTAL SFC IS POSSIBLE
THIS AFTN BUT OVERALL INSTABILITY PROFILES SUGGEST ONLY LIMITED
TSRA POTENTIAL. THE STRONG WIND GUSTS ONGOING AT AFD ISSUANCE
SHOULD SUBSIDE AFTER SUNSET HOWEVER SUSTAINED WINDS ARE EXPECTED
TO REMAIN BETWEEN 10-15 KTS FOR MOST OF THE NIGHT DUE TO THE TIGHT
SFC PRESSURE GRADIENT. TEMPERATURES WILL CONTINUE FALLING THROUGH
THE NIGHT DUE TO STRONG CAA AT LOW LEVELS WITH OVERNIGHT LOWS IN
THE 30S AND 40S...AN IMPRESSIVE SWING FROM THE WIDESPREAD 70S AND
80S NOTED THIS AFTN.
KANOFSKY
&&
.LONG TERM...
ISSUED AT 323 PM CDT THU OCT 25 2012
(FRIDAY THROUGH SATURDAY)
MODEL GUIDANCE HAS TRENDED JUST A BIT FASTER WITH TIMING OF
FROPA/ASSOCIATED WEATHER IMPACTS AFFECTING FAR SE CWA TOMORROW
MORNING. CURRENTLY HAVE SKIES SCATTERING/CLEARING OUT QUICKLY EARLY
TOMORROW WHICH IS SUPPORTED BY MODEL RH PLOTS. HOWEVER...AM A BIT
CONCERNED LOOKING UPSTREAM IN CENTRAL PLAINS WHICH IS CURRENTLY
EXPERIENCING BKN-OVC MVFR CEILINGS. IF LOW CLOUDS HANG ON A BIT
LATER THAN ANTICIPATED...HIGH TEMPERATURES MAY BE A BIT COOLER.
REGARDLESS...EXPECT HIGHS NEARLY 30 DEGREES COOLER TOMORROW IN SOME
AREAS AS STRONG CAA REIGNS THROUGH THE DAY WITH THE 0C 850-HPA
ISOTHERM ADVANCING TO THE CENTRAL PORTION OF THE CWA BY 0000 UTC
SATURDAY.
MAIN CONCERN FOR THE SHORT-TERM PERIOD WILL BE LOW TEMPERATURES ON
FRIDAY NIGHT/EARLY SATURDAY MORNING. WITH CLEAR SKIES...SFC RIDGE
AXIS DRAPED FROM C MO TO NE MO...LIGHT WINDS...AND L/M 20S DEWPOINTS
ADVECTING IN FROM THE NW...EXCELLENT RADIATIONAL COOLING
CONDITIONS SHOULD BE PREVALENT. WITH LOW TEMPERATURES RANGING FROM
27-32...WILL BE ISSUING A FREEZE WATCH THOSE COUNTIES ALONG AND
WEST OF MISSISSIPPI RIVER. THE WATCH VERY WELL MAY NEED TO BE
UPGRADED TO A WARNING IF FORECAST CONFIDENCE INCREASES WITH TIME.
(SUNDAY THROUGH THURSDAY)
DRY WEATHER WITH BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE
REST OF THE PERIOD. NIGHTTIME LOWS WILL BE QUITE CHILLY...WITH THE
COLDEST NIGHT EXPECTED TO BE MONDAY MORNING WHICH MAY BRING ANOTHER
WIDESPREAD FREEZE TO MOST OF THE AREA. A BIT MORE UNCERTAINTY WITH
REGARDS TO SUBFREEZING TEMPERATURES ON SATURDAY NIGHT/SUNDAY MORNING
DUE TO EXPECTED CLOUD COVER. SFC WINDS WILL REMAIN LIGHT/NORTHERLY
THROUGH THE EXTENDED AS SFC RIDGE AXIS REMAINS QUASI-STATIONARY. AT
MID/UPPER LEVELS OF THE ATMOSPHERE...INITIALLY NW FLOW WILL VEER TO
A MORE NORTHERLY COMPONENT AS HURRICANE SANDY PHASES WITH A NORTHERN
STREAM SHORTWAVE TROUGH SOMETIME LATE MONDAY/EARLY TUESDAY OVER THE
EASTERN SEABOARD. THIS LARGE AND POWERFUL SYSTEM WILL ACT TO BLOCK
UPSTREAM FLOW...KEEPING THE LSX CWA COOL AND DRY THROUGH NEXT
THURSDAY.
GOSSELIN
&&
.AVIATION...
ISSUED AT 605 PM CDT THU OCT 25 2012
COLD FRONT HAS CLEARED THE TERMINALS. GUSTY NORTHWEST WIND AND
MVFR CEILINGS TO CONTINUE. BAND OF POST FRONTAL RAIN...WITH IFR
CONDITIONS...WILL MOVE ACROSS STL METRO TERMINALS THROUGH 03Z.
CLEARING ADVERTISED BY MODEL GUIDANCE LOOKS DOUBTFUL GIVEN
UPSTREAM OBS AND SATELLITE IMAGERY. DO NOT SCT OUT CLOUDS UNTIL
LATE FRIDAY AFTERNOON.
SPECIFICS FOR KSTL...
MVFR CEILING AND GUSTY NORTHWEST WIND TO CONTINUE THROUGH FRIDAY
AFTERNOON. BRIEF IFR CONDITIONS POSSIBLE THIS EVENING WITH BAND OF
POST FRONTAL RAIN THAT SHOULD CLEAR TERMINAL COMPLEX BY 02Z.
CLEARING POSSIBLE BY FRIDAY AFTERNOON AS HIGH PRESSURE BUILDS INTO
THE REGION.
CVKING
&&
.PRELIMINARY POINT TEMPS/POPS...
ST LOUIS 40 54 34 54 / 60 10 0 5
QUINCY 33 51 29 51 / 10 5 0 5
COLUMBIA 33 52 28 53 / 10 5 0 5
JEFFERSON CITY 34 53 28 53 / 10 5 0 5
SALEM 43 53 34 54 / 80 30 10 0
FARMINGTON 39 53 31 53 / 80 20 5 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...FREEZE WATCH FROM LATE FRIDAY NIGHT THROUGH SATURDAY MORNING FOR
AUDRAIN MO-BOONE MO-CALLAWAY MO-COLE MO-CRAWFORD MO-
FRANKLIN MO-GASCONADE MO-IRON MO-JEFFERSON MO-KNOX MO-LEWIS
MO-LINCOLN MO-MADISON MO-MARION MO-MONITEAU MO-MONROE MO-
MONTGOMERY MO-OSAGE MO-PIKE MO-RALLS MO-REYNOLDS MO-SHELBY
MO-ST. CHARLES MO-ST. FRANCOIS MO-ST. LOUIS CITY MO-ST.
LOUIS MO-STE. GENEVIEVE MO-WARREN MO-WASHINGTON MO.
IL...FREEZE WATCH FROM LATE FRIDAY NIGHT THROUGH SATURDAY MORNING FOR
ADAMS IL-BROWN IL-CALHOUN IL-GREENE IL-JERSEY IL-MACOUPIN
IL-MADISON IL-MONROE IL-PIKE IL-ST. CLAIR IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
802 PM CDT Thu Oct 25 2012
.UPDATE...
/756 PM CDT Thu Oct 25 2012/
Low cloud deck has become quite extensive upstream and stretches from
western MO all the way into Canada. With trajectories taking this
cloud cover straight into the forecast area, it is hard to see these
clouds clearing out any time soon. RAP has been the only model to
resolve this cloud cover and it keeps the entire area cloudy all
night long. It also maintains some weak gusts through the night with
clouds and ongoing CAA keeping us somewhat mixed. Given the ongoing
CAA and BL moisture that is obviously thicker than other models
think (per 00Z OAX/ABR/UNR soundings), the RAP is likely correct in
keeping us cloudy and breezy through the night and probably well into
tomorrow morning as well. Therefore made significant changes to
clouds and winds overnight. These cloudy and breezy conditions will
also keep temperatures from getting as cold as previously forecast,
though extent of CAA should still let them drop into the lower and
middle 30s which are already on the doorstep.
Hawblitzel
&&
.DISCUSSION...
Tonight through Saturday...
As precipitation exits the forecast area this afternoon, the main
focus for the short term will be temperatures, particularly tonight
and Friday night lows. Models don`t seem to have a good handle on
the widespread stratus building southward across portions of eastern
Nebraska and Iowa, which has the potential to strongly impact the
low temperature forecast tonight. Current water vapor imagery shows
some signs of developing subsidence behind the departing upper-level
jet streak in the eastern Dakotas; however, it is yet to be seen
whether this will translate to erosion of the low-level cloud field
this evening. Both the NAM and RAP do dry out first the midlevels
and eventually the low levels by 06z across southeast Nebraska and
into the forecast area, so have still continued a decreasing trend
in cloudiness tonight, leading to a cooler low temperature forecast
across the area. However, with some near-surface moisture remaining
and a more rapid temperature fall after 06z, do not think that a
freeze will be likely across the region even if clouds clear out
completely.
The setup on Friday night looks much more prototypical for a hard
freeze, with a 1032 mb surface high filtering into the central
Plains, pushing the surface ridge axis over northwest Missouri
shortly after midnight. Temperatures could easily drop into the mid
to upper 20`s across the majority of the region Saturday morning,
and would likely remain below freezing for several hours. If the
forecast remains on track, a freeze warning will be needed for areas
that have not already experienced a hard freeze this fall. The ridge
axis will remain over the region through early afternoon on
Saturday, keeping daytime temperatures 10 to 15 degrees below normal
in the upper 40s to lower 50s.
Laflin
Medium Range (Sunday through Thursday):
High forecast confidence this period as upper level flow remains
stagnant in the wake of a large downstream block formed by the
merging of an eastern trough and Hurricane Sandy into a potential
superstorm. This will maintain a steady northwest upper flow regime
over the regime which further amplify late in the period as
additional troughing builds into the Pacific Northwest.
All in all, precipitation chances are near zero through the period
and the effects of negative thermal advection vs. insolation will
generally offset each other. This will keep temperatures steady
through much of the week with highs in the low-mid 50s and lows in
the low-mid 30s.
Bookbinder
&&
.AVIATION...
For the 00Z TAFs...extensive stratus deck encompasses much of
Nebraska and the Northern Plains with trajectories that point that
moisture straight into western MO overnight. The RAP model is the
only model that has picked up on this cloud deck, and it keeps the KC
area with a persistent MVFR deck through mid Friday morning. Given
some modest low level cold air advection and thick moisture, see no
reason to stray from the RAP solution, so kept MVFR conditions going
all night long for all terminals. These clouds and CAA should keep
the airmass mixed enough to allow some off and on weak gusts to
continue much of the night.
Hawblitzel
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
618 PM CDT Thu Oct 25 2012
...UPDATED AVIATION DISCUSSION...
.DISCUSSION...
Tonight through Saturday...
As precipitation exits the forecast area this afternoon, the main
focus for the short term will be temperatures, particularly tonight
and Friday night lows. Models don`t seem to have a good handle on
the widespread stratus building southward across portions of eastern
Nebraska and Iowa, which has the potential to strongly impact the
low temperature forecast tonight. Current water vapor imagery shows
some signs of developing subsidence behind the departing upper-level
jet streak in the eastern Dakotas; however, it is yet to be seen
whether this will translate to erosion of the low-level cloud field
this evening. Both the NAM and RAP do dry out first the midlevels
and eventually the low levels by 06z across southeast Nebraska and
into the forecast area, so have still continued a decreasing trend
in cloudiness tonight, leading to a cooler low temperature forecast
across the area. However, with some near-surface moisture remaining
and a more rapid temperature fall after 06z, do not think that a
freeze will be likely across the region even if clouds clear out
completely.
The setup on Friday night looks much more prototypical for a hard
freeze, with a 1032 mb surface high filtering into the central
Plains, pushing the surface ridge axis over northwest Missouri
shortly after midnight. Temperatures could easily drop into the mid
to upper 20`s across the majority of the region Saturday morning,
and would likely remain below freezing for several hours. If the
forecast remains on track, a freeze warning will be needed for areas
that have not already experienced a hard freeze this fall. The ridge
axis will remain over the region through early afternoon on
Saturday, keeping daytime temperatures 10 to 15 degrees below normal
in the upper 40s to lower 50s.
Laflin
Medium Range (Sunday through Thursday):
High forecast confidence this period as upper level flow remains
stagnant in the wake of a large downstream block formed by the
merging of an eastern trough and Hurricane Sandy into a potential
superstorm. This will maintain a steady northwest upper flow regime
over the regime which further amplify late in the period as
additional troughing builds into the Pacific Northwest.
All in all, precipitation chances are near zero through the period
and the effects of negative thermal advection vs. insolation will
generally offset each other. This will keep temperatures steady
through much of the week with highs in the low-mid 50s and lows in
the low-mid 30s.
Bookbinder
&&
.AVIATION...
For the 00Z TAFs...extensive stratus deck encompasses much of
Nebraska and the Northern Plains with trajectories that point that
moisture straight into western MO overnight. The RAP model is the
only model that has picked up on this cloud deck, and it keeps the KC
area with a persistent MVFR deck through mid Friday morning. Given
some modest low level cold air advection and thick moisture, see no
reason to stray from the RAP solution, so kept MVFR conditions going
all night long for all terminals. These clouds and CAA should keep
the airmass mixed enough to allow some off and on weak gusts to
continue much of the night.
Hawblitzel
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
402 PM CDT Wed Oct 24 2012
.DISCUSSION...
Today through Saturday...
In the short term, the primary focus will be precipitation chances
with a dynamic cold front approaching from the northwest. Although
most model solutions continue to indicate light, warm sector
precipitation across northwest Missouri this afternoon and evening,
and low level moisture is evident in the scattered to broken MVFR
deck, the weak forcing resulting from slight isentropic lift has not
been enough to produce rain showers ahead of the surface cold front.
Short range hi-res models have caught onto the lack of precipitation
this afternoon, and keep rainfall out of Missouri prior to 06z. Have
hedged a bit earlier than the latest HRRR forecasts in bringing a
chance of precipitation into far northwestern portions of the CWA
for the potential that storms could develop on the boundary and move
into the far northwest before 06z; however, the better chances for
showers and thunderstorms will be Thursday as the main trough axis
dips into southeast Nebraska and begins driving the surface front
more quickly to the southeast.
Both the NAM and GFS produce convective precipitation along the low
level boundary tonight as frontogenesis increases and midlevel
cooling supports temporarily higher lapse rates, mainly above 925mb.
The best chance for any robust storms to develop will likely be
confined to the period between 06z-09z when storms can be rooted
more closely to the surface; afterward, the low-level inversion will
be compounded by surface frontal passage, and the focus for
precipitation will shift a bit closer to the 850mb front. Most
precipitation during the daylight hours on Thursday should occur
mainly along the 850 front, with a small chance for some isolated
development along the surface front in far eastern portions of the
forecast area early Thursday afternoon. Rain chances will linger a
bit across the southeast as midlevel forcing broadens early Friday
evening, with any remaining showers expected to move out shortly
between 00z-06z Friday.
Temperatures will drop significantly behind the cold front, and in
general, highs will be reached just prior to frontal passage on
Thursday. Highs for Friday and Saturday will be well below average
as cold surface high pressure settles into the region, and lows
Friday night could drop a few degrees below freezing across areas
that have not previously received a hard freeze.
Laflin
Medium Range (Saturday Night through Wednesday)...
As the Canadian surface ridge remains settled over the area this
weekend...temperatures will dip to around 30 degrees Sunday morning.
The northern zones have experienced a hard freeze so will have to
make some decisions tomorrow about headlines for the southern three
quarters of the area for Sunday and possibly Monday mornings. The
500-1000mb thicknesses are around 537-540DM by Sunday morning with
very light winds and clear skies.
Lows on Monday morning may be a few degrees warmer as the surface
ridge slides further east. Not much in the way of advection at this
time though and the dry conditions with light winds...may require a
downward tweak of the lows for Monday morning. By Tuesday...we will
see the winds finally swing around to the south as the ridge moves
further east so there will be an increase in the thicknesses and 850
mb temps...therefore we should see above freezing temperatures on
Tuesday and Wednesday mornings.
Daytime highs through the extended will show a gradual warming trend
as well from the 40s on Sunday to the around 60 degrees F by Tuesday
and Wednesday.
Storm track remains well to the north so no precipitation is
expected through the period. Adolphson
&&
.AVIATION...
For the 18z TAFs, MVFR ceilings are expected to mix out during the
next hour, to be replaced by primarily VFR conditions through the
remainder of the period. Southerly winds will gust in the 25-30 kt
range this afternoon, then will gradually decrease to around 10 kts
after sunset. A cold front will bring winds around to the northwest
between 10-14z Thursday, with a chance for showers and thunderstorms
mainly behind the frontal boundary.
Laflin
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION...UPDATED
NWS HASTINGS NE
948 PM CDT THU OCT 25 2012
.UPDATE...LOW CLOUDS HAVE CONTINUED TO ADVANCE SOUTHWARD THROUGH
THE EVENING AND EXPECT THIS TREND WILL CONTINUE WITH LOW CLOUDS
EVENTUALLY COVERING OUR ENTIRE FORECAST AREA BY LATER TONIGHT.
SO THIS UPDATE WAS TO INCREASE CLOUD COVER AND SUBSEQUENTLY
INCREASE LOW TEMPERATURES BY A FEW DEGREES ACROSS NEBRASKA ZONES. THE
EXTENSIVE CLOUD COVER WILL CUT BACK ON THE RADIATIONAL COOLING
TONIGHT...SO ALTHOUGH IT WILL STILL BE COLD...IT WILL NOT BE AS
COLD AS IT COULD BE IF WE WOULD HAVE SEEN SOME BREAKS IN THE
CLOUDS.
&&
.PREV DISCUSSION... /ISSUED 641 PM CDT THU OCT 25 2012/
AVIATION...00Z KGRI TAF. THIS WILL BE ANOTHER VERY COMPLEX
CEILING FORECAST WITH BIG QUESTIONS ON HOW LONG THE LOW CLOUDS
WILL REMAIN OVER THE AREA. THE RUC MODEL SEEMS TO ACTUALLY HAVE A
HANDLE ON THE LOW CLOUDS THAT SEVERAL OF THE OTHER MODELS ARE
TOTALLY MISSING RIGHT NOW. THE RUC KEEPS THESE LOW CLOUDS IN PLACE
THROUGH THE NIGHT AND THUS WE WILL DO LIKEWISE IN OUR KGRI TAF.
THE NAM HAS NO CLOUDS IN KGRI THIS EVENING OR TONIGHT...WHICH IS
ALREADY STARTING OFF ON A VERY WRONG FOOT. HOWEVER...IT DOES HINT
AT HAVING AT LEAST SCATTERED LOW CLOUDS DURING THE DAY TOMORROW.
DECIDED TO REMAIN PESSIMISTIC AND WILL KEEP LOW CEILINGS OF AT
LEAST MVFR CATEGORY IN PLACE THROUGH THE DURATION OF THE TAF
PERIOD...INCLUDING TOMORROW...BUT CONFIDENCE IS WEAK.
PREV DISCUSSION... /ISSUED 336 PM CDT THU OCT 25 2012/
SHORT TERM...
UNSEASONABLE COLD IS NOW ESTABLISHED. THIS AIR MASS HAS ARCTIC
ORIGINS WITH A 1042 MB HIGH OVER AK/NRN CANADA. HIGH TEMPS TDY
ARE 20F BELOW NORMAL!
LOW STRATUS MOVED IN AND KEPT ORD CAPPED AT 34F.
OVERVIEW: ARCTIC HIGH PRES WILL CONT OOZING SWD INTO THE CNTRL
PLAINS UNTIL A PIECE BREAKS OFF FRI AND IS OVERHEAD 00Z/SAT. IN
THE MEANTIME...THE UPSTREAM SHRTWV TROF WILL SLIDE THRU TOMORROW
WITH A POTENT SHOT OF QG FORCING...BUT NO LOW-LEVEL MSTR. SO THE
FCST IS DRY.
UPPER-AIR: 6-HRLY SOUNDINGS BEGAN AT 18Z AND PROBABLY CONT THRU MON
IN SUPPORT OF SANDY. SO EXTRA UA DATA AVAILABLE!
SATL/UPPER-AIR DATA SHOW THE NEXT SHRTWV TROF OVER ID/UT/WY WITH
COLD CLOUDTOPS AND SOME SN. THIS WILL NOT BE THE BIGGEST PLAYER IN
THE FCST. THE STRATUS ON SATL HAS TROUBLE WRITTEN ALL OVER IT WITH
POTENTIAL FOR A FCST BUST.
AN EASY FCST THIS IS NOT. CLOUDS ARE A MAJOR HEADACHE AND THE ENTIRE
FCST HINGES ON THEM TNGT-FRI.
THIS IS AN OLD FASHION FCST AS NO GUIDANCE IS HANDLING THIS LOW OVC.
STRATUS IS EXTENSIVE UPSTREAM AND PROGRESSING SWD. BELIEVE THE
WISEST COURSE OF ACTION TO FCST PERSISTENCE. WHILE BOUNDARY LAYER
MIXING HAS SLOWED ITS FWD PROGRESS...CANNOT SEE ANY REASON FOR
STRATUS TO DISSIPATE...AND ONCE IT COMES IN...SEE NO REASON FOR IT
TO LEAVE. EXTENT UP TO SRN CANADA SUGGESTS ITS TRAPPED UNDERNEATH
FRONTAL/SUBSIDENCE INVERSION. 18Z UNR SOUNDING CONFIRMS.
TNGT: INCREASING CLOUDS AND PROBABLY BECOMING CLOUDY. KEPT LOW
TEMPS FROM 4 AM GID FCST AND ADDED 2-3F. WE`RE WARMER THAN MOST
GUIDANCE. NW WINDS DIMINISH AROUND SUNSET TO 5-10 KTS.
FRI: EVEN IF STRATUS DOES ONLY PARTIALLY COVER THE FCST AREA...MID-
HIGH CLOUDS WILL STILL RESULT IN M/CLOUDY DAY. MAINTAINED TEMPS FROM
4 AM GID FCST AND LOWERED THEM 3F. THIS IS TOWARD THE COLDER END OF
THE GUIDANCE ENVELOPE. NW WINDS AROUND 5 KTS BECOMING LIGHT AND VAR.
POSSIBLE FCST SHORTCOMINGS:
1) FCST IS NOT AS CLOUDY AS I WOULD LIKE. EXPECT EVNG UPDATE TO GO
CLOUDIER.
2) THIS MEANS WE`RE PROBABLY TOO COLD BY 3-5F ON OVERNIGHT LOWS...
FOR AREAS THAT CLOUD-OVER.
3) WOULD`VE LIKED TO GO CLOUDIER. IF LOW OVC HANGS AROUND MUCH OF
FRI AS I EXPECT...OUR HIGH TEMPS MAY BE IN JEOPARDY...WARM BY 5F.
INTERESTING TO NOTE THAT SVRL DAYS AGO...THE GFS 2M TEMPS WERE
CONSISTENTLY FCSTG HIGH IN THE 30S FOR TOMORROW. IF IT REMAINS OVC
AS WE CURRENTLY THINK IT WILL...THE GFS MAY END UP BEING RIGHT.
LONG TERM...SATURDAY THROUGH THURSDAY. THE WEATHER ACROSS THE
CENTRAL PLAINS WILL GENERALLY BE PRETTY QUIET...ESPECIALLY COMPARED
TO THE MID-ATLANTIC AND NEW ENGLAND STATES. FOR US...THIS FORECAST
PERIOD BEGINS PRETTY COOL...WELL BELOW NORMAL THROUGH THE WEEKEND...
FOLLOWED BY SOME WARMING NEXT WEEK.
IN GENERAL...UPPER BLOCK IN NORTH ATLANTIC AND DEVELOPMENT OF SANDY
INTO A LARGE EXTRA-TROPICAL CYCLONE...WILL REALLY BOG THINGS DOWN
FLOW-WISE. KS/NE WILL REMAIN IN THE CYCLONIC...COOL NORTHWEST FLOW
INTO MONDAY/TUESDAY. THAT IMPACTS TEMPERATURES QUITE A BIT...AND
PLAYS IN SLOWING WARMER AIR TRYING TO PUSH INTO THE AREA NEXT WEEK.
OVER THE WEEKEND...MAINLY SATURDAY...A WEAK MID-LEVEL SYSTEM SLIDES
EAST ACROSS NEBRASKA/SOUTH DAKOTA. ASSOCIATED WEAK SURFACE LOW WILL
KICK UP SOUTHERLY WINDS BY AFTERNOON. PLENTY OF MID/HIGH LEVEL CLOUDS
EXPECTED AS THE WARM ADVECTION INCREASES. NORTHERN NEBRASKA REGION
IS LOCATED IN FAVORABLE LEFT FRONT QUADRANT OF H25 JET NOSING IN
FROM THE NORTHWEST. THINK THERE WILL BE SOME PRECIPITATION ASSOCIATED
WITH THIS SYSTEM...BUT AM NOT COMFORTABLE WITH INTRODUCING SOMETHING
MEASURABLE IN THE FORECAST. IF ANYTHING..THERE MAY BE SOME SPRINKLES
OR FLURRIES IN NEBRASKA NORTH OF HIGHWAY 92 SATURDAY. SUBSEQUENT
FORECASTS WILL WANT TO WATCH THIS. THIS SYSTEM CLEARS THE AREA
SUNDAY...AND BELIEVE SUNSHINE WILL OFFSET ANY WEAKISH COLD ADVECTION
SUGGESTED IN THE MODELS.
AS WARM ADVECTION STARTS TO SPREAD ONTO THE PLAINS...CLOUDS MAY POSE
SOME ISSUES FOR TEMPERATURES EARLY IN THE WEEK. TOO EARLY EARLY TO
PUT ANY PRECIPITATION INTO THE FORECAST FROM THAT WARM ADVECTION BUT
ITS CERTAINLY NOT OUT OF THE QUESTION EARLY TUESDAY. AFTER THAT WE
SHOULD START TO SEE WARMING TEMPERATURES BACK TO AROUND NORMAL BY
HALLOWEEN. GHOSTS AND GOBLINS SHOULD HAVE PRETTY NICE TRICK OR TREAT
WEATHER...AND NO ISSUES ARE EXPECTED AS WE WRAP UP OCTOBER AND START
NOVEMBER.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...WESELY
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
928 PM CDT THU OCT 25 2012
.UPDATE...
UPDATED TO INCREASE OVERNIGHT LOWS AND CLOUDS
&&
.DISCUSSION...
LATEST IR IMAGERY CONTS TO INDC A FAIRLY EXPANSIVE STRATUS DECK
ACROSS THE REGION THIS EVENING. MODELS CONT TO STRUGGLE WITH THIS
DECK AND THE ONLY MODEL THAT APPEARS TO HAVE SOME HANDLE ON THE
SITUATION IS THE RAP. THE RAP INDCS THAT THE CLOUDS WILL CONT
THRU THE NIGHT AND ACTUALLY INTO FRI MRNG /ESPECIALLY IN THE WRN
FA/. THE IR IMAGERY DOES INDC SOME HOLES IN THIS DECK AROUND KYKN
AND KSUX THOUGH AND THIS WILL NEED TO BE MONITORED FOR THE CNTRL
AND ERN CWA OVERNIGHT. NEVERTHELESS WITH THE AMOUNT OF CLOUDS IT
APPEARS THAT OVERNIGHT LOWS NEED ADJUSTING UPWARD IN MOST
LOCATIONS WITH UPPER 20S TO LOWER 30S APPEARING REASONABLE.
OTHERWISE THE FORECAST APPEARED TO BE IN GOOD SHAPE.
THE UPDATES WILL BE OUT BY 930 PM.
BOUSTEAD
&&
.PREV DISCUSSION... /ISSUED 559 PM CDT THU OCT 25 2012/
AVIATION...
00Z TAF FOR KOMA...KOFK...KLNK
MODELS ARE HAVING A VERY DIFFICULT TIME WITH THE CLOUD FORECAST
OVERNIGHT. MOST MODELS WOULD INDC GENERALLY CLEAR SKIES WITH
DECREASING WINDS...BUT THIS APPEARS UNLIKELY GIVEN THE LARGE SC
DECK ACROSS...AND UPSTREAM FM THE AREA CURRENTLY. THUS WE WILL GO
WITH A PERSISTENCE FORECAST AT THIS TIME UNTIL MODEL FORECASTS
IMPROVE...OR CLEAR TRENDS IN OBSERVATION DATA DEVELOP. THUS WE
WILL HAVE MVFR CIGS AT ALL SITES THROUGH THE NIGHT. NORTHWEST
WINDS WILL BE DIMINISHING THROUGH THE NIGHT THOUGH AS THE PRESSURE
GRADIENT DECREASES.
BOUSTEAD
PREV DISCUSSION... /ISSUED 313 PM CDT THU OCT 25 2012/
SHORT TERM...TONIGHT THROUGH SUNDAY. MAIN FORECAST PROBLEM IN
THE VERY NEAR TERM IS AN EXPANDING DECK OF STRATUS THAT NO MODEL
EXCEPT THE RAP SEEMS TO BE HANDLING ALL THAT WELL. THUS...HAVE
TRENDED CLOUD GRIDS UPWARD TONIGHT...BUT AM STILL THINKING THAT
SOME OF THIS MAY DISSIPATE THIS EVENING AS MORE ANTICYCLONIC FLOW
CONTINUES TO TAKE HOLD ACROSS THE REGION. IT WILL PROBABLY BE A
COLD NIGHT WITH LOWS IN THE 20S AS SKIES SCATTER OUT. GIVEN THE
RECENT RAINS...THERE COULD BE PATCHY FOG OVERNIGHT...BUT PROBABLY
NOT A BIG ENOUGH OF CONCERN TO ADD TO THE GRIDS.
HIGH PRESSURE CONTINUES TO MOVE OFF THE HIGH PLAINS ON FRIDAY WITH
NORTHWESTERLY FLOW AND SOME MID AND HIGH CLOUDS. HIGH PRESSURE
DRIFTS OVER THE FORECAST AREA FRIDAY EVENING WITH A RETURN FLOW
SETTING UP ON SATURDAY.
A NEW AREA OF LOW PRESSURE DEVELOPS ACROSS SOUTHWEST SOUTH DAKOTA
THROUGH THE DAY SATURDAY WHILE AN UPPER WAVE MOVES THROUGH THE
NORTHERN PLAINS. WARM AIR ADVECTION COULD RESULT IN A FEW SHOWERS
NEAR THE SD/NE BORDER SATURDAY AFTERNOON...THEN SLIDING EAST
SOUTHEAST DOWN THE MISSOURI RIVER VALLEY SATURDAY NIGHT. THE NAM
IS CONSIDERABLY WARMER...WHICH IS PROBABLY TOO WARM. BUT...THERE
COULD BE A FEW RAIN SHOWER OR EVEN A SNOW FLAKE MIXED IN MAINLY
NORTH OF OMAHA SATURDAY NIGHT. DRY WEATHER IS EXPECTED ON SUNDAY.
LONG TERM...SUNDAY NIGHT THROUGH THURSDAY. MEDIUM RANGE MODELS
NOT SHOWING MUCH POTENTIAL FOR ANY PCPN THRU MOST OF NEXT WEEK.
OTHERWISE...LATEST GFS BLOCKING INDICES ADVERTISING UPSTREAM
BLOCKAGE DEVELOPING THRU DAY 7...ALLOWING FOR AMPLIFIED RIDGING
OVER THE ROCKIES/WRN HIGH PLAINS WITH 2 TROFS FLANKING THE CONUS.
THIS THEN LEADING TO THRUST OF COLD AIR DOWN THRU THE UPPER
MIDWEST/GREAT LAKES REGION REACHING ALL THE WAY DOWN TO THE SERN
STATES. AT THIS POINT THEN THE MAIN INTEREST IS HOW FAR WILL THE
WRN PERIPHERY OF CAA PUSH IT INTO THE CWA BEFORE AFOREMENTIONED
ROCKIES/WRN HIGH PLAINS RIDGE BUILDS IN. COMPARISON OF 1000-500MB
THKNS DAYS 5-7...ECM DETERMINIST PROGS CLEARLY SHOW IT TO BE THE
WARMER OF THE TWO. THIS ALSO REFLECTED THRU WARMER ECM MOS MAX/MIN
TEMPS RELATIVE TO THE MEX. GOING FCST APPEAR TO BE IN ACCORDANCE
WITH THE WARMER ECM SOLUTION...THUS SEE NO REASON TO MAKE ANY
CHANGE DEPICTING WARMING TREND IN THE EXTEND PDS.
DEE
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
641 PM CDT THU OCT 25 2012
.AVIATION...00Z KGRI TAF. THIS WILL BE ANOTHER VERY COMPLEX
CEILING FORECAST WITH BIG QUESTIONS ON HOW LONG THE LOW CLOUDS
WILL REMAIN OVER THE AREA. THE RUC MODEL SEEMS TO ACTUALLY HAVE A
HANDLE ON THE LOW CLOUDS THAT SEVERAL OF THE OTHER MODELS ARE
TOTALLY MISSING RIGHT NOW. THE RUC KEEPS THESE LOW CLOUDS IN PLACE
THROUGH THE NIGHT AND THUS WE WILL DO LIKEWISE IN OUR KGRI TAF.
THE NAM HAS NO CLOUDS IN KGRI THIS EVENING OR TONIGHT...WHICH IS
ALREADY STARTING OFF ON A VERY WRONG FOOT. HOWEVER...IT DOES HINT
AT HAVING AT LEAST SCATTERED LOW CLOUDS DURING THE DAY TOMORROW.
DECIDED TO REMAIN PESSIMISTIC AND WILL KEEP LOW CEILINGS OF AT
LEAST MVFR CATEGORY IN PLACE THROUGH THE DURATION OF THE TAF
PERIOD...INCLUDING TOMORROW...BUT CONFIDENCE IS WEAK.
&&
.PREV DISCUSSION... /ISSUED 336 PM CDT THU OCT 25 2012/
SHORT TERM...
UNSEASONABLE COLD IS NOW ESTABLISHED. THIS AIR MASS HAS ARCTIC
ORIGINS WITH A 1042 MB HIGH OVER AK/NRN CANADA. HIGH TEMPS TDY
ARE 20F BELOW NORMAL!
LOW STRATUS MOVED IN AND KEPT ORD CAPPED AT 34F.
OVERVIEW: ARCTIC HIGH PRES WILL CONT OOZING SWD INTO THE CNTRL
PLAINS UNTIL A PIECE BREAKS OFF FRI AND IS OVERHEAD 00Z/SAT. IN
THE MEANTIME...THE UPSTREAM SHRTWV TROF WILL SLIDE THRU TOMORROW
WITH A POTENT SHOT OF QG FORCING...BUT NO LOW-LEVEL MSTR. SO THE
FCST IS DRY.
UPPER-AIR: 6-HRLY SOUNDINGS BEGAN AT 18Z AND PROBABLY CONT THRU MON
IN SUPPORT OF SANDY. SO EXTRA UA DATA AVAILABLE!
SATL/UPPER-AIR DATA SHOW THE NEXT SHRTWV TROF OVER ID/UT/WY WITH
COLD CLOUDTOPS AND SOME SN. THIS WILL NOT BE THE BIGGEST PLAYER IN
THE FCST. THE STRATUS ON SATL HAS TROUBLE WRITTEN ALL OVER IT WITH
POTENTIAL FOR A FCST BUST.
AN EASY FCST THIS IS NOT. CLOUDS ARE A MAJOR HEADACHE AND THE ENTIRE
FCST HINGES ON THEM TNGT-FRI.
THIS IS AN OLD FASHION FCST AS NO GUIDANCE IS HANDLING THIS LOW OVC.
STRATUS IS EXTENSIVE UPSTREAM AND PROGRESSING SWD. BELIEVE THE
WISEST COURSE OF ACTION TO FCST PERSISTENCE. WHILE BOUNDARY LAYER
MIXING HAS SLOWED ITS FWD PROGRESS...CANNOT SEE ANY REASON FOR
STRATUS TO DISSIPATE...AND ONCE IT COMES IN...SEE NO REASON FOR IT
TO LEAVE. EXTENT UP TO SRN CANADA SUGGESTS ITS TRAPPED UNDERNEATH
FRONTAL/SUBSIDENCE INVERSION. 18Z UNR SOUNDING CONFIRMS.
TNGT: INCREASING CLOUDS AND PROBABLY BECOMING CLOUDY. KEPT LOW
TEMPS FROM 4 AM GID FCST AND ADDED 2-3F. WE`RE WARMER THAN MOST
GUIDANCE. NW WINDS DIMINISH AROUND SUNSET TO 5-10 KTS.
FRI: EVEN IF STRATUS DOES ONLY PARTIALLY COVER THE FCST AREA...MID-
HIGH CLOUDS WILL STILL RESULT IN M/CLOUDY DAY. MAINTAINED TEMPS FROM
4 AM GID FCST AND LOWERED THEM 3F. THIS IS TOWARD THE COLDER END OF
THE GUIDANCE ENVELOPE. NW WINDS AROUND 5 KTS BECOMING LIGHT AND VAR.
POSSIBLE FCST SHORTCOMINGS:
1) FCST IS NOT AS CLOUDY AS I WOULD LIKE. EXPECT EVNG UPDATE TO GO
CLOUDIER.
2) THIS MEANS WE`RE PROBABLY TOO COLD BY 3-5F ON OVERNIGHT LOWS...
FOR AREAS THAT CLOUD-OVER.
3) WOULD`VE LIKED TO GO CLOUDIER. IF LOW OVC HANGS AROUND MUCH OF
FRI AS I EXPECT...OUR HIGH TEMPS MAY BE IN JEOPARDY...WARM BY 5F.
INTERESTING TO NOTE THAT SVRL DAYS AGO...THE GFS 2M TEMPS WERE
CONSISTENTLY FCSTG HIGH IN THE 30S FOR TOMORROW. IF IT REMAINS OVC
AS WE CURRENTLY THINK IT WILL...THE GFS MAY END UP BEING RIGHT.
LONG TERM...SATURDAY THROUGH THURSDAY. THE WEATHER ACROSS THE
CENTRAL PLAINS WILL GENERALLY BE PRETTY QUIET...ESPECIALLY COMPARED
TO THE MID-ATLANTIC AND NEW ENGLAND STATES. FOR US...THIS FORECAST
PERIOD BEGINS PRETTY COOL...WELL BELOW NORMAL THROUGH THE WEEKEND...
FOLLOWED BY SOME WARMING NEXT WEEK.
IN GENERAL...UPPER BLOCK IN NORTH ATLANTIC AND DEVELOPMENT OF SANDY
INTO A LARGE EXTRA-TROPICAL CYCLONE...WILL REALLY BOG THINGS DOWN
FLOW-WISE. KS/NE WILL REMAIN IN THE CYCLONIC...COOL NORTHWEST FLOW
INTO MONDAY/TUESDAY. THAT IMPACTS TEMPERATURES QUITE A BIT...AND
PLAYS IN SLOWING WARMER AIR TRYING TO PUSH INTO THE AREA NEXT WEEK.
OVER THE WEEKEND...MAINLY SATURDAY...A WEAK MID-LEVEL SYSTEM SLIDES
EAST ACROSS NEBRASKA/SOUTH DAKOTA. ASSOCIATED WEAK SURFACE LOW WILL
KICK UP SOUTHERLY WINDS BY AFTERNOON. PLENTY OF MID/HIGH LEVEL CLOUDS
EXPECTED AS THE WARM ADVECTION INCREASES. NORTHERN NEBRASKA REGION
IS LOCATED IN FAVORABLE LEFT FRONT QUADRANT OF H25 JET NOSING IN
FROM THE NORTHWEST. THINK THERE WILL BE SOME PRECIPITATION ASSOCIATED
WITH THIS SYSTEM...BUT AM NOT COMFORTABLE WITH INTRODUCING SOMETHING
MEASURABLE IN THE FORECAST. IF ANYTHING..THERE MAY BE SOME SPRINKLES
OR FLURRIES IN NEBRASKA NORTH OF HIGHWAY 92 SATURDAY. SUBSEQUENT
FORECASTS WILL WANT TO WATCH THIS. THIS SYSTEM CLEARS THE AREA
SUNDAY...AND BELIEVE SUNSHINE WILL OFFSET ANY WEAKISH COLD ADVECTION
SUGGESTED IN THE MODELS.
AS WARM ADVECTION STARTS TO SPREAD ONTO THE PLAINS...CLOUDS MAY POSE
SOME ISSUES FOR TEMPERATURES EARLY IN THE WEEK. TOO EARLY EARLY TO
PUT ANY PRECIPITATION INTO THE FORECAST FROM THAT WARM ADVECTION BUT
ITS CERTAINLY NOT OUT OF THE QUESTION EARLY TUESDAY. AFTER THAT WE
SHOULD START TO SEE WARMING TEMPERATURES BACK TO AROUND NORMAL BY
HALLOWEEN. GHOSTS AND GOBLINS SHOULD HAVE PRETTY NICE TRICK OR TREAT
WEATHER...AND NO ISSUES ARE EXPECTED AS WE WRAP UP OCTOBER AND START
NOVEMBER.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
104 PM CDT WED OCT 24 2012
.UPDATE...ONE LAST UPDATE TO DECREASE TEMPERATURES ACROSS OUR
SOUTHEAST. THE TEMPERATURE AT KHJH AND KK61 HAVE REMAINED NEARLY
STEADY IF NOT FALLEN THROUGH THE PAST FEW HOURS...AND WITH
CONTINUED CLOUD COVER AND LOW LEVEL COLD AIR ADVECTION THERE IS
LITTLE REASON TO BELIEVE TEMPERATURES ARE GOING TO REBOUND. WENT
AHEAD AND KEPT AFTERNOON TEMPERATURES IN THE 50S ACROSS MOST ALL
OF THE CWA AS A RESULT. ALSO TWEAKED HOURLY SKY...DEWPOINT AND
WIND GRIDS TO BETTER REFLECT CURRENT TRENDS.
&&
.PREV DISCUSSION... /ISSUED 1234 PM CDT WED OCT 24 2012/
AVIATION...18Z KGRI TAF. PREVAILING IFR CONDITIONS FORECAST
THROUGH 04Z...WITH LIFR CONDITIONS EXPECTED 04Z-09Z...AND
IMPROVING CONDITIONS THEREAFTER. CEILINGS NEAR 600FT AGL ARE
EXPECTED TO PERSIST THROUGH MUCH OF THIS AFTERNOON INTO THIS
EVENING. ALTHOUGH PERIODIC MVFR CEILINGS CANNOT BE RULED OUT THIS
AFTERNOON THROUGH EARLY THIS EVENING...THE PREDOMINANT CEILING
WILL PRESENT IFR CONDITIONS AND SUCH AS BEEN FORECAST IN THE TAF.
-RA STILL APPEARS TO BE A GOOD BET AT THE TERMINAL
TONIGHT...PRIMARILY 04Z-09Z. -RA SHOULD DIMINISH TOWARDS
09Z...WITH -DZ THEN POSSIBLE 09Z-15Z. THE SURFACE WIND WILL REMAIN
FROM THE NORTH...INCREASING IN INTENSITY DURING THE TAF
PERIOD...SUSTAINED NEAR 18KTS AND GUSTING NEAR 25KTS BY THE END OF
THE TAF PERIOD.
PREV DISCUSSION... /ISSUED 1112 AM CDT WED OCT 24 2012/
UPDATE...MORNING UPPER AIR ANALYSIS INDICATES LONG WAVE TROUGHING
OVER THE WESTERN CONUS AND RIDGING OVER THE EAST. MID AND UPPER
LEVEL JET ENERGY EXTENDS FROM CALIFORNIA...NORTHEAST ACROSS THE
CENTRAL ROCKY MOUNTAIN RANGE AND THE NORTHERN PLAINS...EAST ACROSS
ONTARIO AND QUEBEC AND THEN SOUTHEAST ACROSS THE NORTHEASTERN
CONUS. MUCH OF THIS UPPER LEVEL JET ENERGY REMAINS RELEGATED TO
THE NORTHWEST OF OUR AREA...WITH TROPOSPHERIC FLOW OVER OUR AREA
REMAINING FAIRLY WEAK AS A RESULT...MAXING OUT AT AROUND 90KTS
NEAR 150MB PER 12Z SOUNDING DATA FROM KLBF. WATER VAPOR IMAGERY
INDICATES INCREASED VALUES OF MID LEVEL MOISTURE FLOWING IN FROM
THE PACIFIC VIA THE MID LEVEL JET AXIS BUT LIKE THE JET
AXIS...MUCH OF THIS MID LEVEL MOISTURE ALSO REMAINS RELEGATED TO
OUR NORTHWEST. WATER VAPOR IMAGERY ALSO INDICATES A MID LEVEL LOW
OVER SASKATCHEWAN...ANOTHER MID LEVEL LOW OVER THE PACIFIC JUST
OFF THE WASHINGTON COAST...AND A MID LEVEL SHORT WAVE OVER
CALIFORNIA AND NEVADA. AT THE SURFACE A COLD FRONT IS NOTED
EXTENDING FROM SOUTHWESTERN IOWA...SOUTHWEST ACROSS SOUTHEASTERN
NEBRASKA...AS WELL AS NORTHEASTERN TO SOUTHWESTERN KANSAS. THE LOW
LEVEL WIND FIELD ACROSS OUR AREA REMAINS FROM THE NORTH/NORTHEAST
AS A RESULT. SATELLITE IMAGERY INDICATES PLENTY OF CLOUD OVER
NEBRASKA AND NORTHERN KANSAS WITH CEILINGS GENERALLY IN THE
200-600FT AGL RANGE ACROSS OUR CWA. OBSERVATIONS FROM ACROSS OUR
AREA ALSO SUGGEST FOG AND/OR DRIZZLE PERSISTS ACROSS THE
AREA...WITH VISIBILITY RESTRICTIONS GENERALLY IN THE 1-5SM RANGE.
VISIBILITIES CONTINUE TO IMPROVE ACROSS THE AREA AS DRIER LOW
LEVEL AIR ADVECTS IN BEHIND THE LOW LEVEL BAROCLINIC ZONE. ALL
SITES ACROSS THE CWA ARE NOW ABOVE 1/4SM AND AS A RESULT...THE
DENSE FOG ADVISORY WAS ALLOWED TO EXPIRE. CURRENT SATELLITE TRENDS
SUGGEST THE CLOUDS ARE HERE TO STAY FOR MUCH OF THE DAY...WHICH
WILL LIKELY PREVENT TEMPERATURES FROM GOING MUCH OF
ANYWHERE...ESPECIALLY WITH WEAK LOW LEVEL COLD AIR ADVECTION ALSO
SETTLING IN POST-FROPA. GIVEN THIS...WENT AHEAD AND DECREASED
AFTERNOON TEMPERATURES A TOUCH...BUT EVEN THEN MAJOR CHANGES WERE
NOT REQUIRED AS THE GOING FORECAST ALREADY HAD THIS WELL IN HAND.
BY FAR THE GREATEST DECREASE IN TEMPERATURES WERE PRESENTED TO OUR
SOUTHEASTERN CWA WHERE IT WAS EARLIER BELIEVED SLOWER FROPA WOULD
PRESENT WARMER TEMPERATURES ACROSS THAT AREA...BUT NOW THAT THE
FRONT HAS CLEARED AND STRATUS HAS SET IN...FEEL CONFIDENT
TEMPERATURES WILL STRUGGLE THROUGH THE 60S EVEN DOWN THAT WAY.
ALSO WENT AHEAD AND TWEAKED HOURLY DATA TO BETTER REFLECT CURRENT
OBSERVATIONS.
PREV DISCUSSION... /ISSUED 709 AM CDT WED OCT 24 2012/
UPDATE...BASED ON LATEST REPORTS OF 1/4 VISIBILITY AT AUTOMATED
AWOS SITES NEAR STOCKTON...OSBORNE AND BELOIT KS...WENT AHEAD AND
ADDED OSBORNE/MITCHELL COUNTIES TO THE ONGOING DENSE FOG HEADLINE
AND ALLOWED SEVERAL COUNTIES ON THE NEBRASKA SIDE TO DROP. THAT
BEING SAID...LOCALIZED VSBY RESTRICTIONS TO WELL UNDER 1 MILE WILL
STILL BE POSSIBLE WELL OUTSIDE OF THE REMAINING ADVISORY
AREA...JUST NOT WIDESPREAD DENSE. MADE NO OTHER CHANGES TO
PREVIOUS FORECAST AT THIS TIME...BUT LATEST HRRR/RAP RUNS CONTINUE
TO SUGGEST THAT HIGH TEMPS MAY STILL BE 10+ DEGREES TOO HIGH IN
THE SOUTHEASTERN CWA DESPITE EARLIER CUTS...AS MOST
MODELS/GUIDANCE CONTINUE TO PERFORM INCREDIBLY POORLY ON DAYTIME
TEMPS EVEN JUST 12-24 HOURS OUT THANKS TO DOMINANT STRATUS TRENDS.
PREV DISCUSSION... /ISSUED 546 AM CDT WED OCT 24 2012/
SHORT TERM...THROUGH FRIDAY NIGHT. CERTAINLY THE VAST MAJORITY OF
WEATHER CHALLENGES DURING THESE NEXT 72 HOURS OCCUR DURING THE
FIRST 24...AS LOCALLY DENSE FOG THIS MORNING EVENTUALLY GIVES WAY
TO WHAT SHOULD BE FAR THE BEST 6-12 HOUR WINDOW FOR MEASURABLE
PRECIP DURING THE NEXT WEEK.
09Z OBJECTIVE SURFACE ANALYSIS PLACED A SLOW MOVING TO NEARLY
STATIONARY COLD FRONT ALONG AN AXIS FROM WEST CENTRAL KS TO
NORTHEAST KS/SOUTHEAST NE...OR BARELY CUTTING ACROSS THE FAR
SOUTHERN CWA AROUND MITCHELL COUNTY KS. AN ELONGATED LOW PRESSURE
AREA AROUND 1003MB EXTENDED ALONG THIS BOUNDARY FROM CENTRAL KS TO
SOUTHEAST CO. NORTH OF THIS BOUNDARY...THE MAJORITY OF THE CWA WAS
EXPERIENCING STEADY NORTH-NORTHEAST BREEZES OF 10-15 MPH...EXCEPT
FOR LIGHTER SPEEDS IN CLOSEST PROXIMITY TO THE BOUNDARY. JUST
AHEAD OF THE SOUTHWARD SINKING INCREASE IN NORTH WINDS...DENSE FOG
DEVELOPMENT WAS MUCH MORE WIDESPREAD TONIGHT THAN EXPECTED 24
HOURS AGO...ALTHOUGH THIS FAIRLY NARROW SOUTHWEST-NORTHEAST
CORRIDOR OF DENSE FOG CONTINUES SINKING SOUTHEAST...RESULTING IN
IMPROVING CONDITIONS IN NORTHERN COUNTIES AND DETERIORATING
CONDITIONS IN SOUTHERN COUNTIES. ALOFT...WATER VAPOR SATELLITE AND
SHORT TERM MODEL DATA CONFIRM INCREASINGLY DIFFLUENT SOUTHWESTERLY
FLOW OVER THE CENTRAL PLAINS...DOWNSTREAM FROM A BROAD LARGE SCALE
TROUGH OVER THE WESTERN CONUS THAT IS ANCHORED BY DUAL 500MB
CLOSED LOWS...ONE OFF THE WASHINGTON COAST...AND ANOTHER OVER
SOUTHERN SASKATCHEWAN.
EARLY THIS MORNING...THE MOST IMMEDIATE ISSUE IS DENSE FOG
TRENDS...AND THE HANDLING OF THE ONGOING DENSE FOG ADVISORY
THROUGH 15Z FOR MUCH OF THE CENTRAL/SOUTHERN CWA. EARLIER LET
SEVERAL OF THE NORTHERN-MOST COUNTIES EXPIRE...AS INCREASING NORTH
WINDS HAD SUFFICIENTLY MIXED VISIBILITIES WELL ABOVE 1/4
MILE...AND A GLANCE AT LATEST OBS AND VISIBILITY PROGS FROM THE
LATEST HRRR SUGGEST THAT ANOTHER FEW TIERS OF COUNTIES ON THE
NORTHERN EDGE OF THE ADVISORY COULD PROBABLY BE EXPIRED SHORTLY AS
WELL...SO STAY TUNED FOR MORE UPDATES PRIOR TO 1130Z.
OTHERWISE...THE GENERAL EXPECTATION FOR TODAY REMAINS MUCH THE
SAME AS 24 HOURS AGO...AS THE COLD FRONT WILL CONTINUE MAKING SLOW
PROGRESS TOWARD THE SOUTHEAST CORNER OF THE CWA...BUT WILL ALSO
REMAIN SOMEWHAT STATIONARY THROUGH THE DAY AS IT GETS HUNG UP IN
RESPONSE TO THE DEVELOPMENT OF AN INCREASINGLY STRONGER SURFACE
LOW CENTER OVER EASTERN CO...WHICH DEVELOPS IN RESPONSE TO THE
STEADY APPROACH OF A STRONG MID LEVEL SHORTWAVE MOVING INTO THE
CENTRAL ROCKIES. THROUGH THE OFFICIAL DAYTIME PERIOD THROUGH
00Z...HAVE CONTINUED TO LEAVE ALL MENTION OF MEASURABLE PRECIP OUT
OF THE CWA...ALTHOUGH DO HAVE A MENTION OF GENERALLY NON-
MEASURABLE PATCHY LIGHT DRIZZLE ACROSS ROUGHLY THE NORTHWEST 1/2
CORRESPONDING TO THE MOST CONCENTRATED AREA OF LOW LEVEL
SATURATION UP TO OR IN EXCESS OF 850MB...AND ALSO SUGGESTED BY THE
TELLTALE BLOTCHY LIGHT QPF FIELDS EVIDENT IN BOTH THE NAM/GFS. ANY
POSSIBLE THREAT FOR SURFACE-BASED THUNDERSTORMS THIS AFTERNOON
APPEARS TO FOCUS JUST SOUTHEAST OF THE CWA...AND WOULD MOST LIKELY
NOT EVEN FORM AT ALL BEFORE SUNSET. TEMP-WISE...AFTER BIG BUSTS
THE PAST FEW DAYS IN MOST AREAS...YET ANOTHER VERY DICEY SETUP
PRESENTS ITSELF TODAY...AS WIDESPREAD STRATUS SHOULD DOMINATE ALL
BUT MAYBE A FEW FAR SOUTHEASTERN COUNTIES ESSENTIALLY ALL DAY
LONG...WHICH COMBINED WITH NORTHERLY BREEZES SHOULD KEEP TEMPS
FROM GOING MUCH OF ANYWHERE. BASED HEAVILY ON 00Z MET/00Z NAM
GUIDANCE...DECIDED TO SLASH PREVIOUS FORECAST HIGHS AT LEAST 7-10
DEGREES IN MOST AREAS...NOW AIMING FOR A RANGE FROM UPPER 40S
NORTH...ONLY LOW-MID 50S TRI-CITIES AND A MIX OF 60S AND 70S
ACROSS ROUGHLY THE SOUTHEAST 1/3 OF THE CWA. THAT BEING
SAID...STAY TUNED FOR UPDATES...AS THE LATEST HRRR VALID THROUGH
20Z SUGGESTS THAT EVEN THESE SOUTHEAST AREAS MAY STILL BE AIMED
WAY TOO WARM. IT MIGHT VERY WELL TURN OUT THAT THE MAJORITY OF THE
CWA STRUGGLES TO RISE MORE THAN 5-8 DEGREES FROM CURRENT VALUES
EARLY THIS MORNING.
TONIGHT...THE MAIN STORY CONTINUES TO BE INCREASING PRECIP
CHANCES...AS LARGE SCALE FORCING RAMPS UP CONSIDERABLY AS THE MID
LEVEL VORT MAX AND UPPER LEVEL JET STREAK SWING INTO THE CENTRAL
PLAINS. WHILE THERE IS AN OUTSIDE CHANCE THAT A FEW NEAR-SURFACE
BASED STORMS COULD FIRE EARLY THIS EVENING VERY NEAR THE SOUTHEAST
CORNER OF THE CWA...THE MUCH MORE LIKELY SCENARIO FOR THE LOCAL
AREA WILL BE A STEADY IGNITION OF ELEVATED SHOWERS/STORMS
STREAMING FROM SOUTHWEST-NORTHEAST ACROSS VARIOUS PARTS OF THE
CWA...BUT ESPECIALLY FOR NORTHERN AND EASTERN COUNTIES WHERE
LIKELY 60-70 POPS WERE MAINTAINED. WITH THE 06Z NAM ADVERTISING
ELEVATED INSTABILITY OF AT LEAST 500-1000 J/KG ACROSS SEVERAL
SOUTHEAST COUNTIES AND ESPECIALLY IN NORTH CENTRAL KANSAS...HAVE
CONTINUED STRONG TO MARGINALLY SEVERE HAIL-STORM WORDING IN THE
HWO...WHICH IS RIGHT IN LINE WITH THE 5 PERCENT HAIL PROBS ON THE
SPC DAY 1 OUTLOOK. NOT EXPECTING THIS TO BE A WIDESPREAD OR LONG-
LASTING STRONG/SEVERE EVENT THOUGH. TURNING TO OTHER OVERNIGHT
ELEMENTS...HAVE INTRODUCED A SLIGHT CHANCE OF LIGHT SNOW TO THE
EXTREME NORTHWEST CWA IN PARTS OF VALLEY/DAWSON COUNTIES COUNTIES
AFTER MIDNIGHT...BUT WOULD BE VERY SURPRISED TO SEE MORE THAN A
VERY LIGHT DUSTING...IF IT EVEN ACCUMULATES AT ALL...AS MUCH
BETTER POTENTIAL FOR 1+ INCHES OF WET SNOW WILL FOCUS 50+ MILES
WEST-NORTHWEST OF THE CWA. ALSO...ALTHOUGH NOT EXPECTING THE NEED
FOR A FORMAL WIND ADVISORY...A WELL-DEFINED PRESSURE RISE SURGE
OVERNIGHT COULD EASILY BRING A FEW HOURS OF NEAR-30 MPH SUSTAINED
NORTH WINDS WITH GUSTS TO AROUND 40 MPH...AND THIS HAS BEEN ADDED
TO THE HAZARDOUS WEATHER OUTLOOK. CHANGED LOW TEMPS LITTLE RANGING
FROM MID 30S NORTHWEST TO LOW 40S SOUTHEAST. RAINFALL AMOUNTS
TONIGHT FOR THE MAJORITY OF THE AREA WILL LIKELY AVERAGE UNDER
0.25-INCH...EXCEPT FOR LOCALLY HIGHER THUNDERSTORM-ENHANCED
CORRIDORS.
TURNING TO THE THURSDAY/THURSDAY NIGHT...CONSENSUS OF VARIOUS
MODELS SUGGESTS MOST IF NOT ALL OF THE CWA WILL BE PRECIP-FREE BY
SUNRISE THURSDAY MORNING AS FORCING QUICKLY DEPARTS TO THE EAST.
AS A RESULT...PULLED NEARLY ALL POPS FROM THE MORNING PERIOD...BUT
DID LEAVE A SLIGHT CHANCE OF A LIGHT RAIN/SNOW MIX IN SOME FAR
NORTHERN AREAS THROUGH 15Z TO ACCOUNT FOR THE PRESENCE OF A
QUICKLY DEPARTING MID-LEVEL DEFORMATION ZONE. OTHERWISE...THURS
WILL REMAIN QUITE BREEZY WITH SUSTAINED SPEEDS 20-25 MPH AND
HIGHER GUSTS AS INCREASING SUNSHINE RESULTS IN INCREASED MIXING.
MADE LITTLE CHANGE TO HIGH TEMPS WITH A CHILLY DAY IN STORE
RANGING MID 40S NORTH TO LOW 50S SOUTH. THURS NIGHT...A TRAILING
REINFORCING SHORTWAVE WILL BRING SOME LIGHT SNOW AS CLOSE AS
EXTREME NORTHWEST KS/SOUTHWEST NEB...BUT ONLY PASSING MID LEVEL
CLOUDS ARE EXPECTED LOCALLY AS NORTH WINDS DECREASE. LOWERED LOWS
2-4 DEGREES FROM PREVIOUS FORECAST ESPECIALLY NORTHWEST...NOW
PUTTING MOST AREAS IN THE MID-UPPER 20S WHICH FOR MUCH OF THE AREA
COULD BE THE FIRST HARD FREEZE SINCE OCT. 7TH.
FRIDAY/FRIDAY NIGHT...A DRY AND SEASONABLY CHILLY FORECAST
CONTINUES...ALTHOUGH A FEW MOISTURE-STARVED PASSING SHORTWAVES
COULD BRING A FEW BATCHES OF PASSING MID LEVEL CLOUDS. BREEZES
FRIDAY WILL AVERAGE NO MORE THAN 5-10 MPH AS SURFACE HIGH PRESSURE
SETTLES DIRECTLY OVER THE AREA...AND ONLY MADE A VERY SLIGHT
UPWARD NUDGE TO HIGH TEMPS...WITH NEARLY ALL AREAS TOPPING OUT NO
BETTER THAN MID-UPPER 40S. FRIDAY NIGHT...LOW TEMPS COULD REALLY
BOTTOM OUT IN SOME AREAS OR POSSIBLY BE HELD UP BY PLENTY OF
PASSING MID LEVEL CLOUDS. AS A RESULT...GENERALLY PLAYED CLOSE TO
PREVIOUS FORECAST WITH VALUES SIMILAR TO THURS NIGHT IN THE MID-
UPPER 20S FOR MOST AREAS.
LONG TERM...STARTING 12Z SATURDAY...A FAIRLY QUIET WEATHER PATTERN
APPEARS TO BE IN STORE FOR THE LOCAL AREA THROUGH THE EXTENDED
PERIODS AS THE LONGWAVE TROUGH MOVING ONSHORE ACROSS THE WEST
COAST THIS MORNING IS EXPECTED TO BEGIN EXITING THE PLAINS BY
SATURDAY. LATEST GLOBAL SCALE MODELS ARE IN GOOD AGREEMENT
SWINGING THE AXIS OF THIS UPPER TROUGH INTO THE OHIO VALLEY BY
SUNDAY MORNING... KEEPING THE LOCAL AREA IN A GENERALLY
NORTHWESTERLY FLOW PATTERN ALOFT THROUGH EARLY NEXT WEEK. WITH NO
NOTABLE DISTURBANCES EMBEDDED IN THIS FLOW...EXPECT DRY CONDITIONS
TO PREVAIL ACROSS THE LOCAL AREA SATURDAY THROUGH TUESDAY. IN
FACT...WITH HEIGHTS RISING AHEAD OF AN UPPER LEVEL RIDGE OF HIGH
PRESSURE EXPECTED TO TRANSITION FROM THE INTERMOUNTAIN WEST INTO
THE PLAINS BY TUESDAY...EXPECT A SLOW WARMING TREND TO START OFF
THE NEW WEEK...AS 850MB TEMPS CLIMB APPROXIMATELY 10C BETWEEN
SATURDAY AND TUESDAY. THIS INCREASE IN TEMPERATURES ALOFT SHOULD
ALLOW AFTERNOON TEMPS TO CLIMB FROM THE 40S ON SATURDAY...TO THE
LOWER 60S IN SPOTS BY TUESDAY AFTERNOON...WHICH IS ACTUALLY A FEW
DEGREES ABOVE CLIMATOLOGY FOR LATE OCTOBER. ADDITIONALLY...IF THE
CURRENT PATTERN PANS OUT...CONTINUED PLEASANT AND DRY WEATHER
LOOKS PLAUSIBLE FOR HALLOWEEN...WHICH LIES JUST BEYOND THE EXTENT
OF THE CURRENT FORECAST...WITH HIGH TEMPERATURES POTENTIALLY
CLIMBING IN THE MID 60S NEXT WEDNESDAY AFTERNOON.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
104 PM UPDATE/AVIATION/1112 AM UPDATE...BRYANT
709 AM UPDATE/SHORT TERM...PFANNKUCH
LONG TERM...ROSSI
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1234 PM CDT WED OCT 24 2012
.AVIATION...18Z KGRI TAF. PREVAILING IFR CONDITIONS FORECAST
THROUGH 04Z...WITH LIFR CONDITIONS EXPECTED 04Z-09Z...AND
IMPROVING CONDITIONS THEREAFTER. CEILINGS NEAR 600FT AGL ARE
EXPECTED TO PERSIST THROUGH MUCH OF THIS AFTERNOON INTO THIS
EVENING. ALTHOUGH PERIODIC MVFR CEILINGS CANNOT BE RULED OUT THIS
AFTERNOON THROUGH EARLY THIS EVENING...THE PREDOMINANT CEILING
WILL PRESENT IFR CONDITIONS AND SUCH AS BEEN FORECAST IN THE TAF.
-RA STILL APPEARS TO BE A GOOD BET AT THE TERMINAL
TONIGHT...PRIMARILY 04Z-09Z. -RA SHOULD DIMINISH TOWARDS
09Z...WITH -DZ THEN POSSIBLE 09Z-15Z. THE SURFACE WIND WILL REMAIN
FROM THE NORTH...INCREASING IN INTENSITY DURING THE TAF
PERIOD...SUSTAINED NEAR 18KTS AND GUSTING NEAR 25KTS BY THE END OF
THE TAF PERIOD.
&&
.PREV DISCUSSION... /ISSUED 1112 AM CDT WED OCT 24 2012/
UPDATE...MORNING UPPER AIR ANALYSIS INDICATES LONG WAVE TROUGHING
OVER THE WESTERN CONUS AND RIDGING OVER THE EAST. MID AND UPPER
LEVEL JET ENERGY EXTENDS FROM CALIFORNIA...NORTHEAST ACROSS THE
CENTRAL ROCKY MOUNTAIN RANGE AND THE NORTHERN PLAINS...EAST ACROSS
ONTARIO AND QUEBEC AND THEN SOUTHEAST ACROSS THE NORTHEASTERN
CONUS. MUCH OF THIS UPPER LEVEL JET ENERGY REMAINS RELEGATED TO
THE NORTHWEST OF OUR AREA...WITH TROPOSPHERIC FLOW OVER OUR AREA
REMAINING FAIRLY WEAK AS A RESULT...MAXING OUT AT AROUND 90KTS
NEAR 150MB PER 12Z SOUNDING DATA FROM KLBF. WATER VAPOR IMAGERY
INDICATES INCREASED VALUES OF MID LEVEL MOISTURE FLOWING IN FROM
THE PACIFIC VIA THE MID LEVEL JET AXIS BUT LIKE THE JET
AXIS...MUCH OF THIS MID LEVEL MOISTURE ALSO REMAINS RELEGATED TO
OUR NORTHWEST. WATER VAPOR IMAGERY ALSO INDICATES A MID LEVEL LOW
OVER SASKATCHEWAN...ANOTHER MID LEVEL LOW OVER THE PACIFIC JUST
OFF THE WASHINGTON COAST...AND A MID LEVEL SHORT WAVE OVER
CALIFORNIA AND NEVADA. AT THE SURFACE A COLD FRONT IS NOTED
EXTENDING FROM SOUTHWESTERN IOWA...SOUTHWEST ACROSS SOUTHEASTERN
NEBRASKA...AS WELL AS NORTHEASTERN TO SOUTHWESTERN KANSAS. THE LOW
LEVEL WIND FIELD ACROSS OUR AREA REMAINS FROM THE NORTH/NORTHEAST
AS A RESULT. SATELLITE IMAGERY INDICATES PLENTY OF CLOUD OVER
NEBRASKA AND NORTHERN KANSAS WITH CEILINGS GENERALLY IN THE
200-600FT AGL RANGE ACROSS OUR CWA. OBSERVATIONS FROM ACROSS OUR
AREA ALSO SUGGEST FOG AND/OR DRIZZLE PERSISTS ACROSS THE
AREA...WITH VISIBILITY RESTRICTIONS GENERALLY IN THE 1-5SM RANGE.
VISIBILITIES CONTINUE TO IMPROVE ACROSS THE AREA AS DRIER LOW
LEVEL AIR ADVECTS IN BEHIND THE LOW LEVEL BAROCLINIC ZONE. ALL
SITES ACROSS THE CWA ARE NOW ABOVE 1/4SM AND AS A RESULT...THE
DENSE FOG ADVISORY WAS ALLOWED TO EXPIRE. CURRENT SATELLITE TRENDS
SUGGEST THE CLOUDS ARE HERE TO STAY FOR MUCH OF THE DAY...WHICH
WILL LIKELY PREVENT TEMPERATURES FROM GOING MUCH OF
ANYWHERE...ESPECIALLY WITH WEAK LOW LEVEL COLD AIR ADVECTION ALSO
SETTLING IN POST-FROPA. GIVEN THIS...WENT AHEAD AND DECREASED
AFTERNOON TEMPERATURES A TOUCH...BUT EVEN THEN MAJOR CHANGES WERE
NOT REQUIRED AS THE GOING FORECAST ALREADY HAD THIS WELL IN HAND.
BY FAR THE GREATEST DECREASE IN TEMPERATURES WERE PRESENTED TO OUR
SOUTHEASTERN CWA WHERE IT WAS EARLIER BELIEVED SLOWER FROPA WOULD
PRESENT WARMER TEMPERATURES ACROSS THAT AREA...BUT NOW THAT THE
FRONT HAS CLEARED AND STRATUS HAS SET IN...FEEL CONFIDENT
TEMPERATURES WILL STRUGGLE THROUGH THE 60S EVEN DOWN THAT WAY.
ALSO WENT AHEAD AND TWEAKED HOURLY DATA TO BETTER REFLECT CURRENT
OBSERVATIONS.
PREV DISCUSSION... /ISSUED 709 AM CDT WED OCT 24 2012/
UPDATE...BASED ON LATEST REPORTS OF 1/4 VISIBILITY AT AUTOMATED
AWOS SITES NEAR STOCKTON...OSBORNE AND BELOIT KS...WENT AHEAD AND
ADDED OSBORNE/MITCHELL COUNTIES TO THE ONGOING DENSE FOG HEADLINE
AND ALLOWED SEVERAL COUNTIES ON THE NEBRASKA SIDE TO DROP. THAT
BEING SAID...LOCALIZED VSBY RESTRICTIONS TO WELL UNDER 1 MILE WILL
STILL BE POSSIBLE WELL OUTSIDE OF THE REMAINING ADVISORY
AREA...JUST NOT WIDESPREAD DENSE. MADE NO OTHER CHANGES TO
PREVIOUS FORECAST AT THIS TIME...BUT LATEST HRRR/RAP RUNS CONTINUE
TO SUGGEST THAT HIGH TEMPS MAY STILL BE 10+ DEGREES TOO HIGH IN
THE SOUTHEASTERN CWA DESPITE EARLIER CUTS...AS MOST
MODELS/GUIDANCE CONTINUE TO PERFORM INCREDIBLY POORLY ON DAYTIME
TEMPS EVEN JUST 12-24 HOURS OUT THANKS TO DOMINANT STRATUS TRENDS.
PREV DISCUSSION... /ISSUED 546 AM CDT WED OCT 24 2012/
SHORT TERM...THROUGH FRIDAY NIGHT. CERTAINLY THE VAST MAJORITY OF
WEATHER CHALLENGES DURING THESE NEXT 72 HOURS OCCUR DURING THE
FIRST 24...AS LOCALLY DENSE FOG THIS MORNING EVENTUALLY GIVES WAY
TO WHAT SHOULD BE FAR THE BEST 6-12 HOUR WINDOW FOR MEASURABLE
PRECIP DURING THE NEXT WEEK.
09Z OBJECTIVE SURFACE ANALYSIS PLACED A SLOW MOVING TO NEARLY
STATIONARY COLD FRONT ALONG AN AXIS FROM WEST CENTRAL KS TO
NORTHEAST KS/SOUTHEAST NE...OR BARELY CUTTING ACROSS THE FAR
SOUTHERN CWA AROUND MITCHELL COUNTY KS. AN ELONGATED LOW PRESSURE
AREA AROUND 1003MB EXTENDED ALONG THIS BOUNDARY FROM CENTRAL KS TO
SOUTHEAST CO. NORTH OF THIS BOUNDARY...THE MAJORITY OF THE CWA WAS
EXPERIENCING STEADY NORTH-NORTHEAST BREEZES OF 10-15 MPH...EXCEPT
FOR LIGHTER SPEEDS IN CLOSEST PROXIMITY TO THE BOUNDARY. JUST
AHEAD OF THE SOUTHWARD SINKING INCREASE IN NORTH WINDS...DENSE FOG
DEVELOPMENT WAS MUCH MORE WIDESPREAD TONIGHT THAN EXPECTED 24
HOURS AGO...ALTHOUGH THIS FAIRLY NARROW SOUTHWEST-NORTHEAST
CORRIDOR OF DENSE FOG CONTINUES SINKING SOUTHEAST...RESULTING IN
IMPROVING CONDITIONS IN NORTHERN COUNTIES AND DETERIORATING
CONDITIONS IN SOUTHERN COUNTIES. ALOFT...WATER VAPOR SATELLITE AND
SHORT TERM MODEL DATA CONFIRM INCREASINGLY DIFFLUENT SOUTHWESTERLY
FLOW OVER THE CENTRAL PLAINS...DOWNSTREAM FROM A BROAD LARGE SCALE
TROUGH OVER THE WESTERN CONUS THAT IS ANCHORED BY DUAL 500MB
CLOSED LOWS...ONE OFF THE WASHINGTON COAST...AND ANOTHER OVER
SOUTHERN SASKATCHEWAN.
EARLY THIS MORNING...THE MOST IMMEDIATE ISSUE IS DENSE FOG
TRENDS...AND THE HANDLING OF THE ONGOING DENSE FOG ADVISORY
THROUGH 15Z FOR MUCH OF THE CENTRAL/SOUTHERN CWA. EARLIER LET
SEVERAL OF THE NORTHERN-MOST COUNTIES EXPIRE...AS INCREASING NORTH
WINDS HAD SUFFICIENTLY MIXED VISIBILITIES WELL ABOVE 1/4
MILE...AND A GLANCE AT LATEST OBS AND VISIBILITY PROGS FROM THE
LATEST HRRR SUGGEST THAT ANOTHER FEW TIERS OF COUNTIES ON THE
NORTHERN EDGE OF THE ADVISORY COULD PROBABLY BE EXPIRED SHORTLY AS
WELL...SO STAY TUNED FOR MORE UPDATES PRIOR TO 1130Z.
OTHERWISE...THE GENERAL EXPECTATION FOR TODAY REMAINS MUCH THE
SAME AS 24 HOURS AGO...AS THE COLD FRONT WILL CONTINUE MAKING SLOW
PROGRESS TOWARD THE SOUTHEAST CORNER OF THE CWA...BUT WILL ALSO
REMAIN SOMEWHAT STATIONARY THROUGH THE DAY AS IT GETS HUNG UP IN
RESPONSE TO THE DEVELOPMENT OF AN INCREASINGLY STRONGER SURFACE
LOW CENTER OVER EASTERN CO...WHICH DEVELOPS IN RESPONSE TO THE
STEADY APPROACH OF A STRONG MID LEVEL SHORTWAVE MOVING INTO THE
CENTRAL ROCKIES. THROUGH THE OFFICIAL DAYTIME PERIOD THROUGH
00Z...HAVE CONTINUED TO LEAVE ALL MENTION OF MEASURABLE PRECIP OUT
OF THE CWA...ALTHOUGH DO HAVE A MENTION OF GENERALLY NON-
MEASURABLE PATCHY LIGHT DRIZZLE ACROSS ROUGHLY THE NORTHWEST 1/2
CORRESPONDING TO THE MOST CONCENTRATED AREA OF LOW LEVEL
SATURATION UP TO OR IN EXCESS OF 850MB...AND ALSO SUGGESTED BY THE
TELLTALE BLOTCHY LIGHT QPF FIELDS EVIDENT IN BOTH THE NAM/GFS. ANY
POSSIBLE THREAT FOR SURFACE-BASED THUNDERSTORMS THIS AFTERNOON
APPEARS TO FOCUS JUST SOUTHEAST OF THE CWA...AND WOULD MOST LIKELY
NOT EVEN FORM AT ALL BEFORE SUNSET. TEMP-WISE...AFTER BIG BUSTS
THE PAST FEW DAYS IN MOST AREAS...YET ANOTHER VERY DICEY SETUP
PRESENTS ITSELF TODAY...AS WIDESPREAD STRATUS SHOULD DOMINATE ALL
BUT MAYBE A FEW FAR SOUTHEASTERN COUNTIES ESSENTIALLY ALL DAY
LONG...WHICH COMBINED WITH NORTHERLY BREEZES SHOULD KEEP TEMPS
FROM GOING MUCH OF ANYWHERE. BASED HEAVILY ON 00Z MET/00Z NAM
GUIDANCE...DECIDED TO SLASH PREVIOUS FORECAST HIGHS AT LEAST 7-10
DEGREES IN MOST AREAS...NOW AIMING FOR A RANGE FROM UPPER 40S
NORTH...ONLY LOW-MID 50S TRI-CITIES AND A MIX OF 60S AND 70S
ACROSS ROUGHLY THE SOUTHEAST 1/3 OF THE CWA. THAT BEING
SAID...STAY TUNED FOR UPDATES...AS THE LATEST HRRR VALID THROUGH
20Z SUGGESTS THAT EVEN THESE SOUTHEAST AREAS MAY STILL BE AIMED
WAY TOO WARM. IT MIGHT VERY WELL TURN OUT THAT THE MAJORITY OF THE
CWA STRUGGLES TO RISE MORE THAN 5-8 DEGREES FROM CURRENT VALUES
EARLY THIS MORNING.
TONIGHT...THE MAIN STORY CONTINUES TO BE INCREASING PRECIP
CHANCES...AS LARGE SCALE FORCING RAMPS UP CONSIDERABLY AS THE MID
LEVEL VORT MAX AND UPPER LEVEL JET STREAK SWING INTO THE CENTRAL
PLAINS. WHILE THERE IS AN OUTSIDE CHANCE THAT A FEW NEAR-SURFACE
BASED STORMS COULD FIRE EARLY THIS EVENING VERY NEAR THE SOUTHEAST
CORNER OF THE CWA...THE MUCH MORE LIKELY SCENARIO FOR THE LOCAL
AREA WILL BE A STEADY IGNITION OF ELEVATED SHOWERS/STORMS
STREAMING FROM SOUTHWEST-NORTHEAST ACROSS VARIOUS PARTS OF THE
CWA...BUT ESPECIALLY FOR NORTHERN AND EASTERN COUNTIES WHERE
LIKELY 60-70 POPS WERE MAINTAINED. WITH THE 06Z NAM ADVERTISING
ELEVATED INSTABILITY OF AT LEAST 500-1000 J/KG ACROSS SEVERAL
SOUTHEAST COUNTIES AND ESPECIALLY IN NORTH CENTRAL KANSAS...HAVE
CONTINUED STRONG TO MARGINALLY SEVERE HAIL-STORM WORDING IN THE
HWO...WHICH IS RIGHT IN LINE WITH THE 5 PERCENT HAIL PROBS ON THE
SPC DAY 1 OUTLOOK. NOT EXPECTING THIS TO BE A WIDESPREAD OR LONG-
LASTING STRONG/SEVERE EVENT THOUGH. TURNING TO OTHER OVERNIGHT
ELEMENTS...HAVE INTRODUCED A SLIGHT CHANCE OF LIGHT SNOW TO THE
EXTREME NORTHWEST CWA IN PARTS OF VALLEY/DAWSON COUNTIES COUNTIES
AFTER MIDNIGHT...BUT WOULD BE VERY SURPRISED TO SEE MORE THAN A
VERY LIGHT DUSTING...IF IT EVEN ACCUMULATES AT ALL...AS MUCH
BETTER POTENTIAL FOR 1+ INCHES OF WET SNOW WILL FOCUS 50+ MILES
WEST-NORTHWEST OF THE CWA. ALSO...ALTHOUGH NOT EXPECTING THE NEED
FOR A FORMAL WIND ADVISORY...A WELL-DEFINED PRESSURE RISE SURGE
OVERNIGHT COULD EASILY BRING A FEW HOURS OF NEAR-30 MPH SUSTAINED
NORTH WINDS WITH GUSTS TO AROUND 40 MPH...AND THIS HAS BEEN ADDED
TO THE HAZARDOUS WEATHER OUTLOOK. CHANGED LOW TEMPS LITTLE RANGING
FROM MID 30S NORTHWEST TO LOW 40S SOUTHEAST. RAINFALL AMOUNTS
TONIGHT FOR THE MAJORITY OF THE AREA WILL LIKELY AVERAGE UNDER
0.25-INCH...EXCEPT FOR LOCALLY HIGHER THUNDERSTORM-ENHANCED
CORRIDORS.
TURNING TO THE THURSDAY/THURSDAY NIGHT...CONSENSUS OF VARIOUS
MODELS SUGGESTS MOST IF NOT ALL OF THE CWA WILL BE PRECIP-FREE BY
SUNRISE THURSDAY MORNING AS FORCING QUICKLY DEPARTS TO THE EAST.
AS A RESULT...PULLED NEARLY ALL POPS FROM THE MORNING PERIOD...BUT
DID LEAVE A SLIGHT CHANCE OF A LIGHT RAIN/SNOW MIX IN SOME FAR
NORTHERN AREAS THROUGH 15Z TO ACCOUNT FOR THE PRESENCE OF A
QUICKLY DEPARTING MID-LEVEL DEFORMATION ZONE. OTHERWISE...THURS
WILL REMAIN QUITE BREEZY WITH SUSTAINED SPEEDS 20-25 MPH AND
HIGHER GUSTS AS INCREASING SUNSHINE RESULTS IN INCREASED MIXING.
MADE LITTLE CHANGE TO HIGH TEMPS WITH A CHILLY DAY IN STORE
RANGING MID 40S NORTH TO LOW 50S SOUTH. THURS NIGHT...A TRAILING
REINFORCING SHORTWAVE WILL BRING SOME LIGHT SNOW AS CLOSE AS
EXTREME NORTHWEST KS/SOUTHWEST NEB...BUT ONLY PASSING MID LEVEL
CLOUDS ARE EXPECTED LOCALLY AS NORTH WINDS DECREASE. LOWERED LOWS
2-4 DEGREES FROM PREVIOUS FORECAST ESPECIALLY NORTHWEST...NOW
PUTTING MOST AREAS IN THE MID-UPPER 20S WHICH FOR MUCH OF THE AREA
COULD BE THE FIRST HARD FREEZE SINCE OCT. 7TH.
FRIDAY/FRIDAY NIGHT...A DRY AND SEASONABLY CHILLY FORECAST
CONTINUES...ALTHOUGH A FEW MOISTURE-STARVED PASSING SHORTWAVES
COULD BRING A FEW BATCHES OF PASSING MID LEVEL CLOUDS. BREEZES
FRIDAY WILL AVERAGE NO MORE THAN 5-10 MPH AS SURFACE HIGH PRESSURE
SETTLES DIRECTLY OVER THE AREA...AND ONLY MADE A VERY SLIGHT
UPWARD NUDGE TO HIGH TEMPS...WITH NEARLY ALL AREAS TOPPING OUT NO
BETTER THAN MID-UPPER 40S. FRIDAY NIGHT...LOW TEMPS COULD REALLY
BOTTOM OUT IN SOME AREAS OR POSSIBLY BE HELD UP BY PLENTY OF
PASSING MID LEVEL CLOUDS. AS A RESULT...GENERALLY PLAYED CLOSE TO
PREVIOUS FORECAST WITH VALUES SIMILAR TO THURS NIGHT IN THE MID-
UPPER 20S FOR MOST AREAS.
LONG TERM...STARTING 12Z SATURDAY...A FAIRLY QUIET WEATHER PATTERN
APPEARS TO BE IN STORE FOR THE LOCAL AREA THROUGH THE EXTENDED
PERIODS AS THE LONGWAVE TROUGH MOVING ONSHORE ACROSS THE WEST
COAST THIS MORNING IS EXPECTED TO BEGIN EXITING THE PLAINS BY
SATURDAY. LATEST GLOBAL SCALE MODELS ARE IN GOOD AGREEMENT
SWINGING THE AXIS OF THIS UPPER TROUGH INTO THE OHIO VALLEY BY
SUNDAY MORNING... KEEPING THE LOCAL AREA IN A GENERALLY
NORTHWESTERLY FLOW PATTERN ALOFT THROUGH EARLY NEXT WEEK. WITH NO
NOTABLE DISTURBANCES EMBEDDED IN THIS FLOW...EXPECT DRY CONDITIONS
TO PREVAIL ACROSS THE LOCAL AREA SATURDAY THROUGH TUESDAY. IN
FACT...WITH HEIGHTS RISING AHEAD OF AN UPPER LEVEL RIDGE OF HIGH
PRESSURE EXPECTED TO TRANSITION FROM THE INTERMOUNTAIN WEST INTO
THE PLAINS BY TUESDAY...EXPECT A SLOW WARMING TREND TO START OFF
THE NEW WEEK...AS 850MB TEMPS CLIMB APPROXIMATELY 10C BETWEEN
SATURDAY AND TUESDAY. THIS INCREASE IN TEMPERATURES ALOFT SHOULD
ALLOW AFTERNOON TEMPS TO CLIMB FROM THE 40S ON SATURDAY...TO THE
LOWER 60S IN SPOTS BY TUESDAY AFTERNOON...WHICH IS ACTUALLY A FEW
DEGREES ABOVE CLIMATOLOGY FOR LATE OCTOBER. ADDITIONALLY...IF THE
CURRENT PATTERN PANS OUT...CONTINUED PLEASANT AND DRY WEATHER
LOOKS PLAUSIBLE FOR HALLOWEEN...WHICH LIES JUST BEYOND THE EXTENT
OF THE CURRENT FORECAST...WITH HIGH TEMPERATURES POTENTIALLY
CLIMBING IN THE MID 60S NEXT WEDNESDAY AFTERNOON.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AVIATION/1112 AM UPDATE...BRYANT
709 AM UPDATE/SHORT TERM...PFANNKUCH
LONG TERM...ROSSI
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1112 AM CDT WED OCT 24 2012
.UPDATE...MORNING UPPER AIR ANALYSIS INDICATES LONG WAVE TROUGHING
OVER THE WESTERN CONUS AND RIDGING OVER THE EAST. MID AND UPPER
LEVEL JET ENERGY EXTENDS FROM CALIFORNIA...NORTHEAST ACROSS THE
CENTRAL ROCKY MOUNTAIN RANGE AND THE NORTHERN PLAINS...EAST ACROSS
ONTARIO AND QUEBEC AND THEN SOUTHEAST ACROSS THE NORTHEASTERN
CONUS. MUCH OF THIS UPPER LEVEL JET ENERGY REMAINS RELEGATED TO
THE NORTHWEST OF OUR AREA...WITH TROPOSPHERIC FLOW OVER OUR AREA
REMAINING FAIRLY WEAK AS A RESULT...MAXING OUT AT AROUND 90KTS
NEAR 150MB PER 12Z SOUNDING DATA FROM KLBF. WATER VAPOR IMAGERY
INDICATES INCREASED VALUES OF MID LEVEL MOISTURE FLOWING IN FROM
THE PACIFIC VIA THE MID LEVEL JET AXIS BUT LIKE THE JET
AXIS...MUCH OF THIS MID LEVEL MOISTURE ALSO REMAINS RELEGATED TO
OUR NORTHWEST. WATER VAPOR IMAGERY ALSO INDICATES A MID LEVEL LOW
OVER SASKATCHEWAN...ANOTHER MID LEVEL LOW OVER THE PACIFIC JUST
OFF THE WASHINGTON COAST...AND A MID LEVEL SHORT WAVE OVER
CALIFORNIA AND NEVADA. AT THE SURFACE A COLD FRONT IS NOTED
EXTENDING FROM SOUTHWESTERN IOWA...SOUTHWEST ACROSS SOUTHEASTERN
NEBRASKA...AS WELL AS NORTHEASTERN TO SOUTHWESTERN KANSAS. THE LOW
LEVEL WIND FIELD ACROSS OUR AREA REMAINS FROM THE NORTH/NORTHEAST
AS A RESULT. SATELLITE IMAGERY INDICATES PLENTY OF CLOUD OVER
NEBRASKA AND NORTHERN KANSAS WITH CEILINGS GENERALLY IN THE
200-600FT AGL RANGE ACROSS OUR CWA. OBSERVATIONS FROM ACROSS OUR
AREA ALSO SUGGEST FOG AND/OR DRIZZLE PERSISTS ACROSS THE
AREA...WITH VISIBILITY RESTRICTIONS GENERALLY IN THE 1-5SM RANGE.
VISIBILITIES CONTINUE TO IMPROVE ACROSS THE AREA AS DRIER LOW
LEVEL AIR ADVECTS IN BEHIND THE LOW LEVEL BAROCLINIC ZONE. ALL
SITES ACROSS THE CWA ARE NOW ABOVE 1/4SM AND AS A RESULT...THE
DENSE FOG ADVISORY WAS ALLOWED TO EXPIRE. CURRENT SATELLITE TRENDS
SUGGEST THE CLOUDS ARE HERE TO STAY FOR MUCH OF THE DAY...WHICH
WILL LIKELY PREVENT TEMPERATURES FROM GOING MUCH OF
ANYWHERE...ESPECIALLY WITH WEAK LOW LEVEL COLD AIR ADVECTION ALSO
SETTLING IN POST-FROPA. GIVEN THIS...WENT AHEAD AND DECREASED
AFTERNOON TEMPERATURES A TOUCH...BUT EVEN THEN MAJOR CHANGES WERE
NOT REQUIRED AS THE GOING FORECAST ALREADY HAD THIS WELL IN HAND.
BY FAR THE GREATEST DECREASE IN TEMPERATURES WERE PRESENTED TO OUR
SOUTHEASTERN CWA WHERE IT WAS EARLIER BELIEVED SLOWER FROPA WOULD
PRESENT WARMER TEMPERATURES ACROSS THAT AREA...BUT NOW THAT THE
FRONT HAS CLEARED AND STRATUS HAS SET IN...FEEL CONFIDENT
TEMPERATURES WILL STRUGGLE THROUGH THE 60S EVEN DOWN THAT WAY.
ALSO WENT AHEAD AND TWEAKED HOURLY DATA TO BETTER REFLECT CURRENT
OBSERVATIONS.
&&
.PREV DISCUSSION... /ISSUED 709 AM CDT WED OCT 24 2012/
UPDATE...BASED ON LATEST REPORTS OF 1/4 VISIBILITY AT AUTOMATED
AWOS SITES NEAR STOCKTON...OSBORNE AND BELOIT KS...WENT AHEAD AND
ADDED OSBORNE/MITCHELL COUNTIES TO THE ONGOING DENSE FOG HEADLINE
AND ALLOWED SEVERAL COUNTIES ON THE NEBRASKA SIDE TO DROP. THAT
BEING SAID...LOCALIZED VSBY RESTRICTIONS TO WELL UNDER 1 MILE WILL
STILL BE POSSIBLE WELL OUTSIDE OF THE REMAINING ADVISORY
AREA...JUST NOT WIDESPREAD DENSE. MADE NO OTHER CHANGES TO
PREVIOUS FORECAST AT THIS TIME...BUT LATEST HRRR/RAP RUNS CONTINUE TO
SUGGEST THAT HIGH TEMPS MAY STILL BE 10+ DEGREES TOO HIGH IN THE
SOUTHEASTERN CWA DESPITE EARLIER CUTS...AS MOST MODELS/GUIDANCE
CONTINUE TO PERFORM INCREDIBLY POORLY ON DAYTIME TEMPS EVEN JUST
12-24 HOURS OUT THANKS TO DOMINANT STRATUS TRENDS.
PREV DISCUSSION... /ISSUED 604 AM CDT WED OCT 24 2012/
AVIATION...12Z KGRI TAF...GENERALLY POOR AVIATION CONDITIONS ARE
EXPECTED AT THE TERMINAL TODAY...AS ALTHOUGH LIFR VSBYS ASSOCIATED
WITH DENSE FOG EARLY THIS MORNING ARE EXPECTED TO IMPROVE BY
24/12Z-24/16Z...IFR STRATUS DECK IS EXPECTED TO CONTINUE THROUGH
MUCH OF THE DAY. IN ADDITION...SOME SHRAS AND TSRAS WILL BE
POSSIBLE AT THE TERMINAL THIS EVENING...AND INCLUDED A PROB30
GROUP TO COVER THIS POSSIBILITY. WINDS TODAY WILL GENERALLY BE
NORTHERLY AT 15-18KTS...GUSTING AS HIGH AS 25KTS AT TIMES.
PREV DISCUSSION... /ISSUED 546 AM CDT WED OCT 24 2012/
SHORT TERM...THROUGH FRIDAY NIGHT. CERTAINLY THE VAST MAJORITY OF
WEATHER CHALLENGES DURING THESE NEXT 72 HOURS OCCUR DURING THE
FIRST 24...AS LOCALLY DENSE FOG THIS MORNING EVENTUALLY GIVES WAY
TO WHAT SHOULD BE FAR THE BEST 6-12 HOUR WINDOW FOR MEASURABLE
PRECIP DURING THE NEXT WEEK.
09Z OBJECTIVE SURFACE ANALYSIS PLACED A SLOW MOVING TO NEARLY
STATIONARY COLD FRONT ALONG AN AXIS FROM WEST CENTRAL KS TO
NORTHEAST KS/SOUTHEAST NE...OR BARELY CUTTING ACROSS THE FAR
SOUTHERN CWA AROUND MITCHELL COUNTY KS. AN ELONGATED LOW PRESSURE
AREA AROUND 1003MB EXTENDED ALONG THIS BOUNDARY FROM CENTRAL KS TO
SOUTHEAST CO. NORTH OF THIS BOUNDARY...THE MAJORITY OF THE CWA WAS
EXPERIENCING STEADY NORTH-NORTHEAST BREEZES OF 10-15 MPH...EXCEPT
FOR LIGHTER SPEEDS IN CLOSEST PROXIMITY TO THE BOUNDARY. JUST
AHEAD OF THE SOUTHWARD SINKING INCREASE IN NORTH WINDS...DENSE FOG
DEVELOPMENT WAS MUCH MORE WIDESPREAD TONIGHT THAN EXPECTED 24
HOURS AGO...ALTHOUGH THIS FAIRLY NARROW SOUTHWEST-NORTHEAST
CORRIDOR OF DENSE FOG CONTINUES SINKING SOUTHEAST...RESULTING IN
IMPROVING CONDITIONS IN NORTHERN COUNTIES AND DETERIORATING
CONDITIONS IN SOUTHERN COUNTIES. ALOFT...WATER VAPOR SATELLITE AND
SHORT TERM MODEL DATA CONFIRM INCREASINGLY DIFFLUENT SOUTHWESTERLY
FLOW OVER THE CENTRAL PLAINS...DOWNSTREAM FROM A BROAD LARGE SCALE
TROUGH OVER THE WESTERN CONUS THAT IS ANCHORED BY DUAL 500MB
CLOSED LOWS...ONE OFF THE WASHINGTON COAST...AND ANOTHER OVER
SOUTHERN SASKATCHEWAN.
EARLY THIS MORNING...THE MOST IMMEDIATE ISSUE IS DENSE FOG
TRENDS...AND THE HANDLING OF THE ONGOING DENSE FOG ADVISORY
THROUGH 15Z FOR MUCH OF THE CENTRAL/SOUTHERN CWA. EARLIER LET
SEVERAL OF THE NORTHERN-MOST COUNTIES EXPIRE...AS INCREASING NORTH
WINDS HAD SUFFICIENTLY MIXED VISIBILITIES WELL ABOVE 1/4
MILE...AND A GLANCE AT LATEST OBS AND VISIBILITY PROGS FROM THE
LATEST HRRR SUGGEST THAT ANOTHER FEW TIERS OF COUNTIES ON THE
NORTHERN EDGE OF THE ADVISORY COULD PROBABLY BE EXPIRED
SHORTLY AS WELL...SO STAY TUNED FOR MORE UPDATES PRIOR TO 1130Z.
OTHERWISE...THE GENERAL EXPECTATION FOR TODAY REMAINS MUCH THE
SAME AS 24 HOURS AGO...AS THE COLD FRONT WILL CONTINUE MAKING SLOW
PROGRESS TOWARD THE SOUTHEAST CORNER OF THE CWA...BUT WILL ALSO
REMAIN SOMEWHAT STATIONARY THROUGH THE DAY AS IT GETS HUNG UP IN
RESPONSE TO THE DEVELOPMENT OF AN INCREASINGLY STRONGER SURFACE
LOW CENTER OVER EASTERN CO...WHICH DEVELOPS IN RESPONSE TO THE
STEADY APPROACH OF A STRONG MID LEVEL SHORTWAVE MOVING INTO THE
CENTRAL ROCKIES. THROUGH THE OFFICIAL DAYTIME PERIOD THROUGH
00Z...HAVE CONTINUED TO LEAVE ALL MENTION OF MEASURABLE PRECIP OUT
OF THE CWA...ALTHOUGH DO HAVE A MENTION OF GENERALLY NON-
MEASURABLE PATCHY LIGHT DRIZZLE ACROSS ROUGHLY THE NORTHWEST 1/2
CORRESPONDING TO THE MOST CONCENTRATED AREA OF LOW LEVEL
SATURATION UP TO OR IN EXCESS OF 850MB...AND ALSO SUGGESTED BY THE
TELLTALE BLOTCHY LIGHT QPF FIELDS EVIDENT IN BOTH THE NAM/GFS. ANY
POSSIBLE THREAT FOR SURFACE-BASED THUNDERSTORMS THIS AFTERNOON
APPEARS TO FOCUS JUST SOUTHEAST OF THE CWA...AND WOULD MOST LIKELY
NOT EVEN FORM AT ALL BEFORE SUNSET. TEMP-WISE...AFTER BIG BUSTS
THE PAST FEW DAYS IN MOST AREAS...YET ANOTHER VERY DICEY SETUP
PRESENTS ITSELF TODAY...AS WIDESPREAD STRATUS SHOULD DOMINATE ALL
BUT MAYBE A FEW FAR SOUTHEASTERN COUNTIES ESSENTIALLY ALL DAY
LONG...WHICH COMBINED WITH NORTHERLY BREEZES SHOULD KEEP TEMPS
FROM GOING MUCH OF ANYWHERE. BASED HEAVILY ON 00Z MET/00Z NAM
GUIDANCE...DECIDED TO SLASH PREVIOUS FORECAST HIGHS AT LEAST 7-10
DEGREES IN MOST AREAS...NOW AIMING FOR A RANGE FROM UPPER 40S
NORTH...ONLY LOW-MID 50S TRI-CITIES AND A MIX OF 60S AND 70S
ACROSS ROUGHLY THE SOUTHEAST 1/3 OF THE CWA. THAT BEING
SAID...STAY TUNED FOR UPDATES...AS THE LATEST HRRR VALID THROUGH
20Z SUGGESTS THAT EVEN THESE SOUTHEAST AREAS MAY STILL BE AIMED
WAY TOO WARM. IT MIGHT VERY WELL TURN OUT THAT THE MAJORITY OF THE
CWA STRUGGLES TO RISE MORE THAN 5-8 DEGREES FROM CURRENT VALUES
EARLY THIS MORNING.
TONIGHT...THE MAIN STORY CONTINUES TO BE INCREASING PRECIP
CHANCES...AS LARGE SCALE FORCING RAMPS UP CONSIDERABLY AS THE MID
LEVEL VORT MAX AND UPPER LEVEL JET STREAK SWING INTO THE CENTRAL
PLAINS. WHILE THERE IS AN OUTSIDE CHANCE THAT A FEW NEAR-SURFACE
BASED STORMS COULD FIRE EARLY THIS EVENING VERY NEAR THE SOUTHEAST
CORNER OF THE CWA...THE MUCH MORE LIKELY SCENARIO FOR THE LOCAL
AREA WILL BE A STEADY IGNITION OF ELEVATED SHOWERS/STORMS
STREAMING FROM SOUTHWEST-NORTHEAST ACROSS VARIOUS PARTS OF THE
CWA...BUT ESPECIALLY FOR NORTHERN AND EASTERN COUNTIES WHERE
LIKELY 60-70 POPS WERE MAINTAINED. WITH THE 06Z NAM ADVERTISING
ELEVATED INSTABILITY OF AT LEAST 500-1000 J/KG ACROSS SEVERAL
SOUTHEAST COUNTIES AND ESPECIALLY IN NORTH CENTRAL KANSAS...HAVE
CONTINUED STRONG TO MARGINALLY SEVERE HAIL-STORM WORDING IN THE
HWO...WHICH IS RIGHT IN LINE WITH THE 5 PERCENT HAIL PROBS ON THE
SPC DAY 1 OUTLOOK. NOT EXPECTING THIS TO BE A WIDESPREAD OR LONG-
LASTING STRONG/SEVERE EVENT THOUGH. TURNING TO OTHER OVERNIGHT
ELEMENTS...HAVE INTRODUCED A SLIGHT CHANCE OF LIGHT SNOW TO THE
EXTREME NORTHWEST CWA IN PARTS OF VALLEY/DAWSON COUNTIES COUNTIES
AFTER MIDNIGHT...BUT WOULD BE VERY SURPRISED TO SEE MORE THAN A
VERY LIGHT DUSTING...IF IT EVEN ACCUMULATES AT ALL...AS MUCH
BETTER POTENTIAL FOR 1+ INCHES OF WET SNOW WILL FOCUS 50+ MILES
WEST-NORTHWEST OF THE CWA. ALSO...ALTHOUGH NOT EXPECTING THE NEED
FOR A FORMAL WIND ADVISORY...A WELL-DEFINED PRESSURE RISE SURGE
OVERNIGHT COULD EASILY BRING A FEW HOURS OF NEAR-30 MPH SUSTAINED
NORTH WINDS WITH GUSTS TO AROUND 40 MPH...AND THIS HAS BEEN ADDED
TO THE HAZARDOUS WEATHER OUTLOOK. CHANGED LOW TEMPS LITTLE RANGING
FROM MID 30S NORTHWEST TO LOW 40S SOUTHEAST. RAINFALL AMOUNTS
TONIGHT FOR THE MAJORITY OF THE AREA WILL LIKELY AVERAGE UNDER
0.25-INCH...EXCEPT FOR LOCALLY HIGHER THUNDERSTORM-ENHANCED
CORRIDORS.
TURNING TO THE THURSDAY/THURSDAY NIGHT...CONSENSUS OF VARIOUS
MODELS SUGGESTS MOST IF NOT ALL OF THE CWA WILL BE PRECIP-FREE BY
SUNRISE THURSDAY MORNING AS FORCING QUICKLY DEPARTS TO THE EAST.
AS A RESULT...PULLED NEARLY ALL POPS FROM THE MORNING PERIOD...BUT
DID LEAVE A SLIGHT CHANCE OF A LIGHT RAIN/SNOW MIX IN SOME FAR
NORTHERN AREAS THROUGH 15Z TO ACCOUNT FOR THE PRESENCE OF A
QUICKLY DEPARTING MID-LEVEL DEFORMATION ZONE. OTHERWISE...THURS
WILL REMAIN QUITE BREEZY WITH SUSTAINED SPEEDS 20-25 MPH AND
HIGHER GUSTS AS INCREASING SUNSHINE RESULTS IN INCREASED MIXING.
MADE LITTLE CHANGE TO HIGH TEMPS WITH A CHILLY DAY IN STORE
RANGING MID 40S NORTH TO LOW 50S SOUTH. THURS NIGHT...A TRAILING
REINFORCING SHORTWAVE WILL BRING SOME LIGHT SNOW AS CLOSE AS
EXTREME NORTHWEST KS/SOUTHWEST NEB...BUT ONLY PASSING MID LEVEL
CLOUDS ARE EXPECTED LOCALLY AS NORTH WINDS DECREASE. LOWERED LOWS
2-4 DEGREES FROM PREVIOUS FORECAST ESPECIALLY NORTHWEST...NOW
PUTTING MOST AREAS IN THE MID-UPPER 20S WHICH FOR MUCH OF THE AREA
COULD BE THE FIRST HARD FREEZE SINCE OCT. 7TH.
FRIDAY/FRIDAY NIGHT...A DRY AND SEASONABLY CHILLY FORECAST
CONTINUES...ALTHOUGH A FEW MOISTURE-STARVED PASSING SHORTWAVES
COULD BRING A FEW BATCHES OF PASSING MID LEVEL CLOUDS. BREEZES
FRIDAY WILL AVERAGE NO MORE THAN 5-10 MPH AS SURFACE HIGH PRESSURE
SETTLES DIRECTLY OVER THE AREA...AND ONLY MADE A VERY SLIGHT
UPWARD NUDGE TO HIGH TEMPS...WITH NEARLY ALL AREAS TOPPING OUT NO
BETTER THAN MID-UPPER 40S. FRIDAY NIGHT...LOW TEMPS COULD REALLY
BOTTOM OUT IN SOME AREAS OR POSSIBLY BE HELD UP BY PLENTY OF
PASSING MID LEVEL CLOUDS. AS A RESULT...GENERALLY PLAYED CLOSE TO
PREVIOUS FORECAST WITH VALUES SIMILAR TO THURS NIGHT IN THE MID-
UPPER 20S FOR MOST AREAS.
LONG TERM...STARTING 12Z SATURDAY...A FAIRLY QUIET WEATHER PATTERN
APPEARS TO BE IN STORE FOR THE LOCAL AREA THROUGH THE EXTENDED
PERIODS AS THE LONGWAVE TROUGH MOVING ONSHORE ACROSS THE WEST COAST
THIS MORNING IS EXPECTED TO BEGIN EXITING THE PLAINS BY SATURDAY.
LATEST GLOBAL SCALE MODELS ARE IN GOOD AGREEMENT SWINGING THE AXIS
OF THIS UPPER TROUGH INTO THE OHIO VALLEY BY SUNDAY MORNING...
KEEPING THE LOCAL AREA IN A GENERALLY NORTHWESTERLY FLOW PATTERN
ALOFT THROUGH EARLY NEXT WEEK. WITH NO NOTABLE DISTURBANCES EMBEDDED
IN THIS FLOW...EXPECT DRY CONDITIONS TO PREVAIL ACROSS THE LOCAL
AREA SATURDAY THROUGH TUESDAY. IN FACT...WITH HEIGHTS RISING AHEAD
OF AN UPPER LEVEL RIDGE OF HIGH PRESSURE EXPECTED TO TRANSITION FROM
THE INTERMOUNTAIN WEST INTO THE PLAINS BY TUESDAY...EXPECT A SLOW
WARMING TREND TO START OFF THE NEW WEEK...AS 850MB TEMPS CLIMB
APPROXIMATELY 10C BETWEEN SATURDAY AND TUESDAY. THIS INCREASE IN
TEMPERATURES ALOFT SHOULD ALLOW AFTERNOON TEMPS TO CLIMB FROM THE
40S ON SATURDAY...TO THE LOWER 60S IN SPOTS BY TUESDAY
AFTERNOON...WHICH IS ACTUALLY A FEW DEGREES ABOVE CLIMATOLOGY FOR
LATE OCTOBER. ADDITIONALLY...IF THE CURRENT PATTERN PANS
OUT...CONTINUED PLEASANT AND DRY WEATHER LOOKS PLAUSIBLE FOR
HALLOWEEN...WHICH LIES JUST BEYOND THE EXTENT OF THE CURRENT
FORECAST...WITH HIGH TEMPERATURES POTENTIALLY CLIMBING IN THE MID
60S NEXT WEDNESDAY AFTERNOON.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
1112 AM UPDATE...BRYANT
709 AM UPDATE/SHORT TERM...PFANNKUCH
LONG TERM/AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS HASTINGS NE
709 AM CDT WED OCT 24 2012
.UPDATE...BASED ON LATEST REPORTS OF 1/4 VISIBILITY AT AUTOMATED
AWOS SITES NEAR STOCKTON...OSBORNE AND BELOIT KS...WENT AHEAD AND
ADDED OSBORNE/MITCHELL COUNTIES TO THE ONGOING DENSE FOG HEADLINE
AND ALLOWED SEVERAL COUNTIES ON THE NEBRASKA SIDE TO DROP. THAT
BEING SAID...LOCALIZED VSBY RESTRICTIONS TO WELL UNDER 1 MILE WILL
STILL BE POSSIBLE WELL OUTSIDE OF THE REMAINING ADVISORY
AREA...JUST NOT WIDESPREAD DENSE. MADE NO OTHER CHANGES TO
PREVIOUS FORECAST AT THIS TIME...BUT LATEST HRRR/RAP RUNS CONTINUE TO
SUGGEST THAT HIGH TEMPS MAY STILL BE 10+ DEGREES TOO HIGH IN THE
SOUTHEASTERN CWA DESPITE EARLIER CUTS...AS MOST MODELS/GUIDANCE
CONTINUE TO PERFORM INCREDIBLY POORLY ON DAYTIME TEMPS EVEN JUST
12-24 HOURS OUT THANKS TO DOMINANT STRATUS TRENDS.
&&
.PREV DISCUSSION... /ISSUED 604 AM CDT WED OCT 24 2012/
AVIATION...12Z KGRI TAF...GENERALLY POOR AVIATION CONDITIONS ARE
EXPECTED AT THE TERMINAL TODAY...AS ALTHOUGH LIFR VSBYS ASSOCIATED
WITH DENSE FOG EARLY THIS MORNING ARE EXPECTED TO IMPROVE BY
24/12Z-24/16Z...IFR STRATUS DECK IS EXPECTED TO CONTINUE THROUGH
MUCH OF THE DAY. IN ADDITION...SOME SHRAS AND TSRAS WILL BE
POSSIBLE AT THE TERMINAL THIS EVENING...AND INCLUDED A PROB30
GROUP TO COVER THIS POSSIBILITY. WINDS TODAY WILL GENERALLY BE
NORTHERLY AT 15-18KTS...GUSTING AS HIGH AS 25KTS AT TIMES.
PREV DISCUSSION... /ISSUED 546 AM CDT WED OCT 24 2012/
SHORT TERM...THROUGH FRIDAY NIGHT. CERTAINLY THE VAST MAJORITY OF
WEATHER CHALLENGES DURING THESE NEXT 72 HOURS OCCUR DURING THE
FIRST 24...AS LOCALLY DENSE FOG THIS MORNING EVENTUALLY GIVES WAY
TO WHAT SHOULD BE FAR THE BEST 6-12 HOUR WINDOW FOR MEASURABLE
PRECIP DURING THE NEXT WEEK.
09Z OBJECTIVE SURFACE ANALYSIS PLACED A SLOW MOVING TO NEARLY
STATIONARY COLD FRONT ALONG AN AXIS FROM WEST CENTRAL KS TO
NORTHEAST KS/SOUTHEAST NE...OR BARELY CUTTING ACROSS THE FAR
SOUTHERN CWA AROUND MITCHELL COUNTY KS. AN ELONGATED LOW PRESSURE
AREA AROUND 1003MB EXTENDED ALONG THIS BOUNDARY FROM CENTRAL KS TO
SOUTHEAST CO. NORTH OF THIS BOUNDARY...THE MAJORITY OF THE CWA WAS
EXPERIENCING STEADY NORTH-NORTHEAST BREEZES OF 10-15 MPH...EXCEPT
FOR LIGHTER SPEEDS IN CLOSEST PROXIMITY TO THE BOUNDARY. JUST
AHEAD OF THE SOUTHWARD SINKING INCREASE IN NORTH WINDS...DENSE FOG
DEVELOPMENT WAS MUCH MORE WIDESPREAD TONIGHT THAN EXPECTED 24
HOURS AGO...ALTHOUGH THIS FAIRLY NARROW SOUTHWEST-NORTHEAST
CORRIDOR OF DENSE FOG CONTINUES SINKING SOUTHEAST...RESULTING IN
IMPROVING CONDITIONS IN NORTHERN COUNTIES AND DETERIORATING
CONDITIONS IN SOUTHERN COUNTIES. ALOFT...WATER VAPOR SATELLITE AND
SHORT TERM MODEL DATA CONFIRM INCREASINGLY DIFFLUENT SOUTHWESTERLY
FLOW OVER THE CENTRAL PLAINS...DOWNSTREAM FROM A BROAD LARGE SCALE
TROUGH OVER THE WESTERN CONUS THAT IS ANCHORED BY DUAL 500MB
CLOSED LOWS...ONE OFF THE WASHINGTON COAST...AND ANOTHER OVER
SOUTHERN SASKATCHEWAN.
EARLY THIS MORNING...THE MOST IMMEDIATE ISSUE IS DENSE FOG
TRENDS...AND THE HANDLING OF THE ONGOING DENSE FOG ADVISORY
THROUGH 15Z FOR MUCH OF THE CENTRAL/SOUTHERN CWA. EARLIER LET
SEVERAL OF THE NORTHERN-MOST COUNTIES EXPIRE...AS INCREASING NORTH
WINDS HAD SUFFICIENTLY MIXED VISIBILITIES WELL ABOVE 1/4
MILE...AND A GLANCE AT LATEST OBS AND VISIBILITY PROGS FROM THE
LATEST HRRR SUGGEST THAT ANOTHER FEW TIERS OF COUNTIES ON THE
NORTHERN EDGE OF THE ADVISORY COULD PROBABLY BE EXPIRED
SHORTLY AS WELL...SO STAY TUNED FOR MORE UPDATES PRIOR TO 1130Z.
OTHERWISE...THE GENERAL EXPECTATION FOR TODAY REMAINS MUCH THE
SAME AS 24 HOURS AGO...AS THE COLD FRONT WILL CONTINUE MAKING SLOW
PROGRESS TOWARD THE SOUTHEAST CORNER OF THE CWA...BUT WILL ALSO
REMAIN SOMEWHAT STATIONARY THROUGH THE DAY AS IT GETS HUNG UP IN
RESPONSE TO THE DEVELOPMENT OF AN INCREASINGLY STRONGER SURFACE
LOW CENTER OVER EASTERN CO...WHICH DEVELOPS IN RESPONSE TO THE
STEADY APPROACH OF A STRONG MID LEVEL SHORTWAVE MOVING INTO THE
CENTRAL ROCKIES. THROUGH THE OFFICIAL DAYTIME PERIOD THROUGH
00Z...HAVE CONTINUED TO LEAVE ALL MENTION OF MEASURABLE PRECIP OUT
OF THE CWA...ALTHOUGH DO HAVE A MENTION OF GENERALLY NON-
MEASURABLE PATCHY LIGHT DRIZZLE ACROSS ROUGHLY THE NORTHWEST 1/2
CORRESPONDING TO THE MOST CONCENTRATED AREA OF LOW LEVEL
SATURATION UP TO OR IN EXCESS OF 850MB...AND ALSO SUGGESTED BY THE
TELLTALE BLOTCHY LIGHT QPF FIELDS EVIDENT IN BOTH THE NAM/GFS. ANY
POSSIBLE THREAT FOR SURFACE-BASED THUNDERSTORMS THIS AFTERNOON
APPEARS TO FOCUS JUST SOUTHEAST OF THE CWA...AND WOULD MOST LIKELY
NOT EVEN FORM AT ALL BEFORE SUNSET. TEMP-WISE...AFTER BIG BUSTS
THE PAST FEW DAYS IN MOST AREAS...YET ANOTHER VERY DICEY SETUP
PRESENTS ITSELF TODAY...AS WIDESPREAD STRATUS SHOULD DOMINATE ALL
BUT MAYBE A FEW FAR SOUTHEASTERN COUNTIES ESSENTIALLY ALL DAY
LONG...WHICH COMBINED WITH NORTHERLY BREEZES SHOULD KEEP TEMPS
FROM GOING MUCH OF ANYWHERE. BASED HEAVILY ON 00Z MET/00Z NAM
GUIDANCE...DECIDED TO SLASH PREVIOUS FORECAST HIGHS AT LEAST 7-10
DEGREES IN MOST AREAS...NOW AIMING FOR A RANGE FROM UPPER 40S
NORTH...ONLY LOW-MID 50S TRI-CITIES AND A MIX OF 60S AND 70S
ACROSS ROUGHLY THE SOUTHEAST 1/3 OF THE CWA. THAT BEING
SAID...STAY TUNED FOR UPDATES...AS THE LATEST HRRR VALID THROUGH
20Z SUGGESTS THAT EVEN THESE SOUTHEAST AREAS MAY STILL BE AIMED
WAY TOO WARM. IT MIGHT VERY WELL TURN OUT THAT THE MAJORITY OF THE
CWA STRUGGLES TO RISE MORE THAN 5-8 DEGREES FROM CURRENT VALUES
EARLY THIS MORNING.
TONIGHT...THE MAIN STORY CONTINUES TO BE INCREASING PRECIP
CHANCES...AS LARGE SCALE FORCING RAMPS UP CONSIDERABLY AS THE MID
LEVEL VORT MAX AND UPPER LEVEL JET STREAK SWING INTO THE CENTRAL
PLAINS. WHILE THERE IS AN OUTSIDE CHANCE THAT A FEW NEAR-SURFACE
BASED STORMS COULD FIRE EARLY THIS EVENING VERY NEAR THE SOUTHEAST
CORNER OF THE CWA...THE MUCH MORE LIKELY SCENARIO FOR THE LOCAL
AREA WILL BE A STEADY IGNITION OF ELEVATED SHOWERS/STORMS
STREAMING FROM SOUTHWEST-NORTHEAST ACROSS VARIOUS PARTS OF THE
CWA...BUT ESPECIALLY FOR NORTHERN AND EASTERN COUNTIES WHERE
LIKELY 60-70 POPS WERE MAINTAINED. WITH THE 06Z NAM ADVERTISING
ELEVATED INSTABILITY OF AT LEAST 500-1000 J/KG ACROSS SEVERAL
SOUTHEAST COUNTIES AND ESPECIALLY IN NORTH CENTRAL KANSAS...HAVE
CONTINUED STRONG TO MARGINALLY SEVERE HAIL-STORM WORDING IN THE
HWO...WHICH IS RIGHT IN LINE WITH THE 5 PERCENT HAIL PROBS ON THE
SPC DAY 1 OUTLOOK. NOT EXPECTING THIS TO BE A WIDESPREAD OR LONG-
LASTING STRONG/SEVERE EVENT THOUGH. TURNING TO OTHER OVERNIGHT
ELEMENTS...HAVE INTRODUCED A SLIGHT CHANCE OF LIGHT SNOW TO THE
EXTREME NORTHWEST CWA IN PARTS OF VALLEY/DAWSON COUNTIES COUNTIES
AFTER MIDNIGHT...BUT WOULD BE VERY SURPRISED TO SEE MORE THAN A
VERY LIGHT DUSTING...IF IT EVEN ACCUMULATES AT ALL...AS MUCH
BETTER POTENTIAL FOR 1+ INCHES OF WET SNOW WILL FOCUS 50+ MILES
WEST-NORTHWEST OF THE CWA. ALSO...ALTHOUGH NOT EXPECTING THE NEED
FOR A FORMAL WIND ADVISORY...A WELL-DEFINED PRESSURE RISE SURGE
OVERNIGHT COULD EASILY BRING A FEW HOURS OF NEAR-30 MPH SUSTAINED
NORTH WINDS WITH GUSTS TO AROUND 40 MPH...AND THIS HAS BEEN ADDED
TO THE HAZARDOUS WEATHER OUTLOOK. CHANGED LOW TEMPS LITTLE RANGING
FROM MID 30S NORTHWEST TO LOW 40S SOUTHEAST. RAINFALL AMOUNTS
TONIGHT FOR THE MAJORITY OF THE AREA WILL LIKELY AVERAGE UNDER
0.25-INCH...EXCEPT FOR LOCALLY HIGHER THUNDERSTORM-ENHANCED
CORRIDORS.
TURNING TO THE THURSDAY/THURSDAY NIGHT...CONSENSUS OF VARIOUS
MODELS SUGGESTS MOST IF NOT ALL OF THE CWA WILL BE PRECIP-FREE BY
SUNRISE THURSDAY MORNING AS FORCING QUICKLY DEPARTS TO THE EAST.
AS A RESULT...PULLED NEARLY ALL POPS FROM THE MORNING PERIOD...BUT
DID LEAVE A SLIGHT CHANCE OF A LIGHT RAIN/SNOW MIX IN SOME FAR
NORTHERN AREAS THROUGH 15Z TO ACCOUNT FOR THE PRESENCE OF A
QUICKLY DEPARTING MID-LEVEL DEFORMATION ZONE. OTHERWISE...THURS
WILL REMAIN QUITE BREEZY WITH SUSTAINED SPEEDS 20-25 MPH AND
HIGHER GUSTS AS INCREASING SUNSHINE RESULTS IN INCREASED MIXING.
MADE LITTLE CHANGE TO HIGH TEMPS WITH A CHILLY DAY IN STORE
RANGING MID 40S NORTH TO LOW 50S SOUTH. THURS NIGHT...A TRAILING
REINFORCING SHORTWAVE WILL BRING SOME LIGHT SNOW AS CLOSE AS
EXTREME NORTHWEST KS/SOUTHWEST NEB...BUT ONLY PASSING MID LEVEL
CLOUDS ARE EXPECTED LOCALLY AS NORTH WINDS DECREASE. LOWERED LOWS
2-4 DEGREES FROM PREVIOUS FORECAST ESPECIALLY NORTHWEST...NOW
PUTTING MOST AREAS IN THE MID-UPPER 20S WHICH FOR MUCH OF THE AREA
COULD BE THE FIRST HARD FREEZE SINCE OCT. 7TH.
FRIDAY/FRIDAY NIGHT...A DRY AND SEASONABLY CHILLY FORECAST
CONTINUES...ALTHOUGH A FEW MOISTURE-STARVED PASSING SHORTWAVES
COULD BRING A FEW BATCHES OF PASSING MID LEVEL CLOUDS. BREEZES
FRIDAY WILL AVERAGE NO MORE THAN 5-10 MPH AS SURFACE HIGH PRESSURE
SETTLES DIRECTLY OVER THE AREA...AND ONLY MADE A VERY SLIGHT
UPWARD NUDGE TO HIGH TEMPS...WITH NEARLY ALL AREAS TOPPING OUT NO
BETTER THAN MID-UPPER 40S. FRIDAY NIGHT...LOW TEMPS COULD REALLY
BOTTOM OUT IN SOME AREAS OR POSSIBLY BE HELD UP BY PLENTY OF
PASSING MID LEVEL CLOUDS. AS A RESULT...GENERALLY PLAYED CLOSE TO
PREVIOUS FORECAST WITH VALUES SIMILAR TO THURS NIGHT IN THE MID-
UPPER 20S FOR MOST AREAS.
LONG TERM...STARTING 12Z SATURDAY...A FAIRLY QUIET WEATHER PATTERN
APPEARS TO BE IN STORE FOR THE LOCAL AREA THROUGH THE EXTENDED
PERIODS AS THE LONGWAVE TROUGH MOVING ONSHORE ACROSS THE WEST COAST
THIS MORNING IS EXPECTED TO BEGIN EXITING THE PLAINS BY SATURDAY.
LATEST GLOBAL SCALE MODELS ARE IN GOOD AGREEMENT SWINGING THE AXIS
OF THIS UPPER TROUGH INTO THE OHIO VALLEY BY SUNDAY MORNING...
KEEPING THE LOCAL AREA IN A GENERALLY NORTHWESTERLY FLOW PATTERN
ALOFT THROUGH EARLY NEXT WEEK. WITH NO NOTABLE DISTURBANCES EMBEDDED
IN THIS FLOW...EXPECT DRY CONDITIONS TO PREVAIL ACROSS THE LOCAL
AREA SATURDAY THROUGH TUESDAY. IN FACT...WITH HEIGHTS RISING AHEAD
OF AN UPPER LEVEL RIDGE OF HIGH PRESSURE EXPECTED TO TRANSITION FROM
THE INTERMOUNTAIN WEST INTO THE PLAINS BY TUESDAY...EXPECT A SLOW
WARMING TREND TO START OFF THE NEW WEEK...AS 850MB TEMPS CLIMB
APPROXIMATELY 10C BETWEEN SATURDAY AND TUESDAY. THIS INCREASE IN
TEMPERATURES ALOFT SHOULD ALLOW AFTERNOON TEMPS TO CLIMB FROM THE
40S ON SATURDAY...TO THE LOWER 60S IN SPOTS BY TUESDAY
AFTERNOON...WHICH IS ACTUALLY A FEW DEGREES ABOVE CLIMATOLOGY FOR
LATE OCTOBER. ADDITIONALLY...IF THE CURRENT PATTERN PANS
OUT...CONTINUED PLEASANT AND DRY WEATHER LOOKS PLAUSIBLE FOR
HALLOWEEN...WHICH LIES JUST BEYOND THE EXTENT OF THE CURRENT
FORECAST...WITH HIGH TEMPERATURES POTENTIALLY CLIMBING IN THE MID
60S NEXT WEDNESDAY AFTERNOON.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR NEZ084>087.
KS...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR KSZ005>007-
017>019.
&&
$$
UPDATE/SHORT TERM...PFANNKUCH
LONG TERM/AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS HASTINGS NE
604 AM CDT WED OCT 24 2012
.AVIATION...12Z KGRI TAF...GENERALLY POOR AVIATION CONDITIONS ARE
EXPECTED AT THE TERMINAL TODAY...AS ALTHOUGH LIFR VSBYS ASSOCIATED
WITH DENSE FOG EARLY THIS MORNING ARE EXPECTED TO IMPROVE BY
24/12Z-24/16Z...IFR STRATUS DECK IS EXPECTED TO CONTINUE THROUGH
MUCH OF THE DAY. IN ADDITION...SOME SHRAS AND TSRAS WILL BE
POSSIBLE AT THE TERMINAL THIS EVENING...AND INCLUDED A PROB30
GROUP TO COVER THIS POSSIBILITY. WINDS TODAY WILL GENERALLY BE
NORTHERLY AT 15-18KTS...GUSTING AS HIGH AS 25KTS AT TIMES.
&&
.PREV DISCUSSION... /ISSUED 546 AM CDT WED OCT 24 2012/
SHORT TERM...THROUGH FRIDAY NIGHT. CERTAINLY THE VAST MAJORITY OF
WEATHER CHALLENGES DURING THESE NEXT 72 HOURS OCCUR DURING THE
FIRST 24...AS LOCALLY DENSE FOG THIS MORNING EVENTUALLY GIVES WAY
TO WHAT SHOULD BE FAR THE BEST 6-12 HOUR WINDOW FOR MEASURABLE
PRECIP DURING THE NEXT WEEK.
09Z OBJECTIVE SURFACE ANALYSIS PLACED A SLOW MOVING TO NEARLY
STATIONARY COLD FRONT ALONG AN AXIS FROM WEST CENTRAL KS TO
NORTHEAST KS/SOUTHEAST NE...OR BARELY CUTTING ACROSS THE FAR
SOUTHERN CWA AROUND MITCHELL COUNTY KS. AN ELONGATED LOW PRESSURE
AREA AROUND 1003MB EXTENDED ALONG THIS BOUNDARY FROM CENTRAL KS TO
SOUTHEAST CO. NORTH OF THIS BOUNDARY...THE MAJORITY OF THE CWA WAS
EXPERIENCING STEADY NORTH-NORTHEAST BREEZES OF 10-15 MPH...EXCEPT
FOR LIGHTER SPEEDS IN CLOSEST PROXIMITY TO THE BOUNDARY. JUST
AHEAD OF THE SOUTHWARD SINKING INCREASE IN NORTH WINDS...DENSE FOG
DEVELOPMENT WAS MUCH MORE WIDESPREAD TONIGHT THAN EXPECTED 24
HOURS AGO...ALTHOUGH THIS FAIRLY NARROW SOUTHWEST-NORTHEAST
CORRIDOR OF DENSE FOG CONTINUES SINKING SOUTHEAST...RESULTING IN
IMPROVING CONDITIONS IN NORTHERN COUNTIES AND DETERIORATING
CONDITIONS IN SOUTHERN COUNTIES. ALOFT...WATER VAPOR SATELLITE AND
SHORT TERM MODEL DATA CONFIRM INCREASINGLY DIFFLUENT SOUTHWESTERLY
FLOW OVER THE CENTRAL PLAINS...DOWNSTREAM FROM A BROAD LARGE SCALE
TROUGH OVER THE WESTERN CONUS THAT IS ANCHORED BY DUAL 500MB
CLOSED LOWS...ONE OFF THE WASHINGTON COAST...AND ANOTHER OVER
SOUTHERN SASKATCHEWAN.
EARLY THIS MORNING...THE MOST IMMEDIATE ISSUE IS DENSE FOG
TRENDS...AND THE HANDLING OF THE ONGOING DENSE FOG ADVISORY
THROUGH 15Z FOR MUCH OF THE CENTRAL/SOUTHERN CWA. EARLIER LET
SEVERAL OF THE NORTHERN-MOST COUNTIES EXPIRE...AS INCREASING NORTH
WINDS HAD SUFFICIENTLY MIXED VISIBILITIES WELL ABOVE 1/4
MILE...AND A GLANCE AT LATEST OBS AND VISIBILITY PROGS FROM THE
LATEST HRRR SUGGEST THAT ANOTHER FEW TIERS OF COUNTIES ON THE
NORTHERN EDGE OF THE ADVISORY COULD PROBABLY BE EXPIRED
SHORTLY AS WELL...SO STAY TUNED FOR MORE UPDATES PRIOR TO 1130Z.
OTHERWISE...THE GENERAL EXPECTATION FOR TODAY REMAINS MUCH THE
SAME AS 24 HOURS AGO...AS THE COLD FRONT WILL CONTINUE MAKING SLOW
PROGRESS TOWARD THE SOUTHEAST CORNER OF THE CWA...BUT WILL ALSO
REMAIN SOMEWHAT STATIONARY THROUGH THE DAY AS IT GETS HUNG UP IN
RESPONSE TO THE DEVELOPMENT OF AN INCREASINGLY STRONGER SURFACE
LOW CENTER OVER EASTERN CO...WHICH DEVELOPS IN RESPONSE TO THE
STEADY APPROACH OF A STRONG MID LEVEL SHORTWAVE MOVING INTO THE
CENTRAL ROCKIES. THROUGH THE OFFICIAL DAYTIME PERIOD THROUGH
00Z...HAVE CONTINUED TO LEAVE ALL MENTION OF MEASURABLE PRECIP OUT
OF THE CWA...ALTHOUGH DO HAVE A MENTION OF GENERALLY NON-
MEASURABLE PATCHY LIGHT DRIZZLE ACROSS ROUGHLY THE NORTHWEST 1/2
CORRESPONDING TO THE MOST CONCENTRATED AREA OF LOW LEVEL
SATURATION UP TO OR IN EXCESS OF 850MB...AND ALSO SUGGESTED BY THE
TELLTALE BLOTCHY LIGHT QPF FIELDS EVIDENT IN BOTH THE NAM/GFS. ANY
POSSIBLE THREAT FOR SURFACE-BASED THUNDERSTORMS THIS AFTERNOON
APPEARS TO FOCUS JUST SOUTHEAST OF THE CWA...AND WOULD MOST LIKELY
NOT EVEN FORM AT ALL BEFORE SUNSET. TEMP-WISE...AFTER BIG BUSTS
THE PAST FEW DAYS IN MOST AREAS...YET ANOTHER VERY DICEY SETUP
PRESENTS ITSELF TODAY...AS WIDESPREAD STRATUS SHOULD DOMINATE ALL
BUT MAYBE A FEW FAR SOUTHEASTERN COUNTIES ESSENTIALLY ALL DAY
LONG...WHICH COMBINED WITH NORTHERLY BREEZES SHOULD KEEP TEMPS
FROM GOING MUCH OF ANYWHERE. BASED HEAVILY ON 00Z MET/00Z NAM
GUIDANCE...DECIDED TO SLASH PREVIOUS FORECAST HIGHS AT LEAST 7-10
DEGREES IN MOST AREAS...NOW AIMING FOR A RANGE FROM UPPER 40S
NORTH...ONLY LOW-MID 50S TRI-CITIES AND A MIX OF 60S AND 70S
ACROSS ROUGHLY THE SOUTHEAST 1/3 OF THE CWA. THAT BEING
SAID...STAY TUNED FOR UPDATES...AS THE LATEST HRRR VALID THROUGH
20Z SUGGESTS THAT EVEN THESE SOUTHEAST AREAS MAY STILL BE AIMED
WAY TOO WARM. IT MIGHT VERY WELL TURN OUT THAT THE MAJORITY OF THE
CWA STRUGGLES TO RISE MORE THAN 5-8 DEGREES FROM CURRENT VALUES
EARLY THIS MORNING.
TONIGHT...THE MAIN STORY CONTINUES TO BE INCREASING PRECIP
CHANCES...AS LARGE SCALE FORCING RAMPS UP CONSIDERABLY AS THE MID
LEVEL VORT MAX AND UPPER LEVEL JET STREAK SWING INTO THE CENTRAL
PLAINS. WHILE THERE IS AN OUTSIDE CHANCE THAT A FEW NEAR-SURFACE
BASED STORMS COULD FIRE EARLY THIS EVENING VERY NEAR THE SOUTHEAST
CORNER OF THE CWA...THE MUCH MORE LIKELY SCENARIO FOR THE LOCAL
AREA WILL BE A STEADY IGNITION OF ELEVATED SHOWERS/STORMS
STREAMING FROM SOUTHWEST-NORTHEAST ACROSS VARIOUS PARTS OF THE
CWA...BUT ESPECIALLY FOR NORTHERN AND EASTERN COUNTIES WHERE
LIKELY 60-70 POPS WERE MAINTAINED. WITH THE 06Z NAM ADVERTISING
ELEVATED INSTABILITY OF AT LEAST 500-1000 J/KG ACROSS SEVERAL
SOUTHEAST COUNTIES AND ESPECIALLY IN NORTH CENTRAL KANSAS...HAVE
CONTINUED STRONG TO MARGINALLY SEVERE HAIL-STORM WORDING IN THE
HWO...WHICH IS RIGHT IN LINE WITH THE 5 PERCENT HAIL PROBS ON THE
SPC DAY 1 OUTLOOK. NOT EXPECTING THIS TO BE A WIDESPREAD OR LONG-
LASTING STRONG/SEVERE EVENT THOUGH. TURNING TO OTHER OVERNIGHT
ELEMENTS...HAVE INTRODUCED A SLIGHT CHANCE OF LIGHT SNOW TO THE
EXTREME NORTHWEST CWA IN PARTS OF VALLEY/DAWSON COUNTIES COUNTIES
AFTER MIDNIGHT...BUT WOULD BE VERY SURPRISED TO SEE MORE THAN A
VERY LIGHT DUSTING...IF IT EVEN ACCUMULATES AT ALL...AS MUCH
BETTER POTENTIAL FOR 1+ INCHES OF WET SNOW WILL FOCUS 50+ MILES
WEST-NORTHWEST OF THE CWA. ALSO...ALTHOUGH NOT EXPECTING THE NEED
FOR A FORMAL WIND ADVISORY...A WELL-DEFINED PRESSURE RISE SURGE
OVERNIGHT COULD EASILY BRING A FEW HOURS OF NEAR-30 MPH SUSTAINED
NORTH WINDS WITH GUSTS TO AROUND 40 MPH...AND THIS HAS BEEN ADDED
TO THE HAZARDOUS WEATHER OUTLOOK. CHANGED LOW TEMPS LITTLE RANGING
FROM MID 30S NORTHWEST TO LOW 40S SOUTHEAST. RAINFALL AMOUNTS
TONIGHT FOR THE MAJORITY OF THE AREA WILL LIKELY AVERAGE UNDER
0.25-INCH...EXCEPT FOR LOCALLY HIGHER THUNDERSTORM-ENHANCED
CORRIDORS.
TURNING TO THE THURSDAY/THURSDAY NIGHT...CONSENSUS OF VARIOUS
MODELS SUGGESTS MOST IF NOT ALL OF THE CWA WILL BE PRECIP-FREE BY
SUNRISE THURSDAY MORNING AS FORCING QUICKLY DEPARTS TO THE EAST.
AS A RESULT...PULLED NEARLY ALL POPS FROM THE MORNING PERIOD...BUT
DID LEAVE A SLIGHT CHANCE OF A LIGHT RAIN/SNOW MIX IN SOME FAR
NORTHERN AREAS THROUGH 15Z TO ACCOUNT FOR THE PRESENCE OF A
QUICKLY DEPARTING MID-LEVEL DEFORMATION ZONE. OTHERWISE...THURS
WILL REMAIN QUITE BREEZY WITH SUSTAINED SPEEDS 20-25 MPH AND
HIGHER GUSTS AS INCREASING SUNSHINE RESULTS IN INCREASED MIXING.
MADE LITTLE CHANGE TO HIGH TEMPS WITH A CHILLY DAY IN STORE
RANGING MID 40S NORTH TO LOW 50S SOUTH. THURS NIGHT...A TRAILING
REINFORCING SHORTWAVE WILL BRING SOME LIGHT SNOW AS CLOSE AS
EXTREME NORTHWEST KS/SOUTHWEST NEB...BUT ONLY PASSING MID LEVEL
CLOUDS ARE EXPECTED LOCALLY AS NORTH WINDS DECREASE. LOWERED LOWS
2-4 DEGREES FROM PREVIOUS FORECAST ESPECIALLY NORTHWEST...NOW
PUTTING MOST AREAS IN THE MID-UPPER 20S WHICH FOR MUCH OF THE AREA
COULD BE THE FIRST HARD FREEZE SINCE OCT. 7TH.
FRIDAY/FRIDAY NIGHT...A DRY AND SEASONABLY CHILLY FORECAST
CONTINUES...ALTHOUGH A FEW MOISTURE-STARVED PASSING SHORTWAVES
COULD BRING A FEW BATCHES OF PASSING MID LEVEL CLOUDS. BREEZES
FRIDAY WILL AVERAGE NO MORE THAN 5-10 MPH AS SURFACE HIGH PRESSURE
SETTLES DIRECTLY OVER THE AREA...AND ONLY MADE A VERY SLIGHT
UPWARD NUDGE TO HIGH TEMPS...WITH NEARLY ALL AREAS TOPPING OUT NO
BETTER THAN MID-UPPER 40S. FRIDAY NIGHT...LOW TEMPS COULD REALLY
BOTTOM OUT IN SOME AREAS OR POSSIBLY BE HELD UP BY PLENTY OF
PASSING MID LEVEL CLOUDS. AS A RESULT...GENERALLY PLAYED CLOSE TO
PREVIOUS FORECAST WITH VALUES SIMILAR TO THURS NIGHT IN THE MID-
UPPER 20S FOR MOST AREAS.
LONG TERM...STARTING 12Z SATURDAY...A FAIRLY QUIET WEATHER PATTERN
APPEARS TO BE IN STORE FOR THE LOCAL AREA THROUGH THE EXTENDED
PERIODS AS THE LONGWAVE TROUGH MOVING ONSHORE ACROSS THE WEST COAST
THIS MORNING IS EXPECTED TO BEGIN EXITING THE PLAINS BY SATURDAY.
LATEST GLOBAL SCALE MODELS ARE IN GOOD AGREEMENT SWINGING THE AXIS
OF THIS UPPER TROUGH INTO THE OHIO VALLEY BY SUNDAY MORNING...
KEEPING THE LOCAL AREA IN A GENERALLY NORTHWESTERLY FLOW PATTERN
ALOFT THROUGH EARLY NEXT WEEK. WITH NO NOTABLE DISTURBANCES EMBEDDED
IN THIS FLOW...EXPECT DRY CONDITIONS TO PREVAIL ACROSS THE LOCAL
AREA SATURDAY THROUGH TUESDAY. IN FACT...WITH HEIGHTS RISING AHEAD
OF AN UPPER LEVEL RIDGE OF HIGH PRESSURE EXPECTED TO TRANSITION FROM
THE INTERMOUNTAIN WEST INTO THE PLAINS BY TUESDAY...EXPECT A SLOW
WARMING TREND TO START OFF THE NEW WEEK...AS 850MB TEMPS CLIMB
APPROXIMATELY 10C BETWEEN SATURDAY AND TUESDAY. THIS INCREASE IN
TEMPERATURES ALOFT SHOULD ALLOW AFTERNOON TEMPS TO CLIMB FROM THE
40S ON SATURDAY...TO THE LOWER 60S IN SPOTS BY TUESDAY
AFTERNOON...WHICH IS ACTUALLY A FEW DEGREES ABOVE CLIMATOLOGY FOR
LATE OCTOBER. ADDITIONALLY...IF THE CURRENT PATTERN PANS
OUT...CONTINUED PLEASANT AND DRY WEATHER LOOKS PLAUSIBLE FOR
HALLOWEEN...WHICH LIES JUST BEYOND THE EXTENT OF THE CURRENT
FORECAST...WITH HIGH TEMPERATURES POTENTIALLY CLIMBING IN THE MID
60S NEXT WEDNESDAY AFTERNOON.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR NEZ048-049-
061>064-073>077-082>087.
KS...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR KSZ005>007-
017.
&&
$$
SHORT TERM...PFANNKUCH
LONG TERM/AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS HASTINGS NE
546 AM CDT WED OCT 24 2012
.SHORT TERM...THROUGH FRIDAY NIGHT. CERTAINLY THE VAST MAJORITY OF
WEATHER CHALLENGES DURING THESE NEXT 72 HOURS OCCUR DURING THE
FIRST 24...AS LOCALLY DENSE FOG THIS MORNING EVENTUALLY GIVES WAY
TO WHAT SHOULD BE FAR THE BEST 6-12 HOUR WINDOW FOR MEASURABLE
PRECIP DURING THE NEXT WEEK.
09Z OBJECTIVE SURFACE ANALYSIS PLACED A SLOW MOVING TO NEARLY
STATIONARY COLD FRONT ALONG AN AXIS FROM WEST CENTRAL KS TO
NORTHEAST KS/SOUTHEAST NE...OR BARELY CUTTING ACROSS THE FAR
SOUTHERN CWA AROUND MITCHELL COUNTY KS. AN ELONGATED LOW PRESSURE
AREA AROUND 1003MB EXTENDED ALONG THIS BOUNDARY FROM CENTRAL KS TO
SOUTHEAST CO. NORTH OF THIS BOUNDARY...THE MAJORITY OF THE CWA WAS
EXPERIENCING STEADY NORTH-NORTHEAST BREEZES OF 10-15 MPH...EXCEPT
FOR LIGHTER SPEEDS IN CLOSEST PROXIMITY TO THE BOUNDARY. JUST
AHEAD OF THE SOUTHWARD SINKING INCREASE IN NORTH WINDS...DENSE FOG
DEVELOPMENT WAS MUCH MORE WIDESPREAD TONIGHT THAN EXPECTED 24
HOURS AGO...ALTHOUGH THIS FAIRLY NARROW SOUTHWEST-NORTHEAST
CORRIDOR OF DENSE FOG CONTINUES SINKING SOUTHEAST...RESULTING IN
IMPROVING CONDITIONS IN NORTHERN COUNTIES AND DETERIORATING
CONDITIONS IN SOUTHERN COUNTIES. ALOFT...WATER VAPOR SATELLITE AND
SHORT TERM MODEL DATA CONFIRM INCREASINGLY DIFFLUENT SOUTHWESTERLY
FLOW OVER THE CENTRAL PLAINS...DOWNSTREAM FROM A BROAD LARGE SCALE
TROUGH OVER THE WESTERN CONUS THAT IS ANCHORED BY DUAL 500MB
CLOSED LOWS...ONE OFF THE WASHINGTON COAST...AND ANOTHER OVER
SOUTHERN SASKATCHEWAN.
EARLY THIS MORNING...THE MOST IMMEDIATE ISSUE IS DENSE FOG
TRENDS...AND THE HANDLING OF THE ONGOING DENSE FOG ADVISORY
THROUGH 15Z FOR MUCH OF THE CENTRAL/SOUTHERN CWA. EARLIER LET
SEVERAL OF THE NORTHERN-MOST COUNTIES EXPIRE...AS INCREASING NORTH
WINDS HAD SUFFICIENTLY MIXED VISIBILITIES WELL ABOVE 1/4
MILE...AND A GLANCE AT LATEST OBS AND VISIBILITY PROGS FROM THE
LATEST HRRR SUGGEST THAT ANOTHER FEW TIERS OF COUNTIES ON THE
NORTHERN EDGE OF THE ADVISORY COULD PROBABLY BE EXPIRED
SHORTLY AS WELL...SO STAY TUNED FOR MORE UPDATES PRIOR TO 1130Z.
OTHERWISE...THE GENERAL EXPECTATION FOR TODAY REMAINS MUCH THE
SAME AS 24 HOURS AGO...AS THE COLD FRONT WILL CONTINUE MAKING SLOW
PROGRESS TOWARD THE SOUTHEAST CORNER OF THE CWA...BUT WILL ALSO
REMAIN SOMEWHAT STATIONARY THROUGH THE DAY AS IT GETS HUNG UP IN
RESPONSE TO THE DEVELOPMENT OF AN INCREASINGLY STRONGER SURFACE
LOW CENTER OVER EASTERN CO...WHICH DEVELOPS IN RESPONSE TO THE
STEADY APPROACH OF A STRONG MID LEVEL SHORTWAVE MOVING INTO THE
CENTRAL ROCKIES. THROUGH THE OFFICIAL DAYTIME PERIOD THROUGH
00Z...HAVE CONTINUED TO LEAVE ALL MENTION OF MEASURABLE PRECIP OUT
OF THE CWA...ALTHOUGH DO HAVE A MENTION OF GENERALLY NON-
MEASURABLE PATCHY LIGHT DRIZZLE ACROSS ROUGHLY THE NORTHWEST 1/2
CORRESPONDING TO THE MOST CONCENTRATED AREA OF LOW LEVEL
SATURATION UP TO OR IN EXCESS OF 850MB...AND ALSO SUGGESTED BY THE
TELLTALE BLOTCHY LIGHT QPF FIELDS EVIDENT IN BOTH THE NAM/GFS. ANY
POSSIBLE THREAT FOR SURFACE-BASED THUNDERSTORMS THIS AFTERNOON
APPEARS TO FOCUS JUST SOUTHEAST OF THE CWA...AND WOULD MOST LIKELY
NOT EVEN FORM AT ALL BEFORE SUNSET. TEMP-WISE...AFTER BIG BUSTS
THE PAST FEW DAYS IN MOST AREAS...YET ANOTHER VERY DICEY SETUP
PRESENTS ITSELF TODAY...AS WIDESPREAD STRATUS SHOULD DOMINATE ALL
BUT MAYBE A FEW FAR SOUTHEASTERN COUNTIES ESSENTIALLY ALL DAY
LONG...WHICH COMBINED WITH NORTHERLY BREEZES SHOULD KEEP TEMPS
FROM GOING MUCH OF ANYWHERE. BASED HEAVILY ON 00Z MET/00Z NAM
GUIDANCE...DECIDED TO SLASH PREVIOUS FORECAST HIGHS AT LEAST 7-10
DEGREES IN MOST AREAS...NOW AIMING FOR A RANGE FROM UPPER 40S
NORTH...ONLY LOW-MID 50S TRI-CITIES AND A MIX OF 60S AND 70S
ACROSS ROUGHLY THE SOUTHEAST 1/3 OF THE CWA. THAT BEING
SAID...STAY TUNED FOR UPDATES...AS THE LATEST HRRR VALID THROUGH
20Z SUGGESTS THAT EVEN THESE SOUTHEAST AREAS MAY STILL BE AIMED
WAY TOO WARM. IT MIGHT VERY WELL TURN OUT THAT THE MAJORITY OF THE
CWA STRUGGLES TO RISE MORE THAN 5-8 DEGREES FROM CURRENT VALUES
EARLY THIS MORNING.
TONIGHT...THE MAIN STORY CONTINUES TO BE INCREASING PRECIP
CHANCES...AS LARGE SCALE FORCING RAMPS UP CONSIDERABLY AS THE MID
LEVEL VORT MAX AND UPPER LEVEL JET STREAK SWING INTO THE CENTRAL
PLAINS. WHILE THERE IS AN OUTSIDE CHANCE THAT A FEW NEAR-SURFACE
BASED STORMS COULD FIRE EARLY THIS EVENING VERY NEAR THE SOUTHEAST
CORNER OF THE CWA...THE MUCH MORE LIKELY SCENARIO FOR THE LOCAL
AREA WILL BE A STEADY IGNITION OF ELEVATED SHOWERS/STORMS
STREAMING FROM SOUTHWEST-NORTHEAST ACROSS VARIOUS PARTS OF THE
CWA...BUT ESPECIALLY FOR NORTHERN AND EASTERN COUNTIES WHERE
LIKELY 60-70 POPS WERE MAINTAINED. WITH THE 06Z NAM ADVERTISING
ELEVATED INSTABILITY OF AT LEAST 500-1000 J/KG ACROSS SEVERAL
SOUTHEAST COUNTIES AND ESPECIALLY IN NORTH CENTRAL KANSAS...HAVE
CONTINUED STRONG TO MARGINALLY SEVERE HAIL-STORM WORDING IN THE
HWO...WHICH IS RIGHT IN LINE WITH THE 5 PERCENT HAIL PROBS ON THE
SPC DAY 1 OUTLOOK. NOT EXPECTING THIS TO BE A WIDESPREAD OR LONG-
LASTING STRONG/SEVERE EVENT THOUGH. TURNING TO OTHER OVERNIGHT
ELEMENTS...HAVE INTRODUCED A SLIGHT CHANCE OF LIGHT SNOW TO THE
EXTREME NORTHWEST CWA IN PARTS OF VALLEY/DAWSON COUNTIES COUNTIES
AFTER MIDNIGHT...BUT WOULD BE VERY SURPRISED TO SEE MORE THAN A
VERY LIGHT DUSTING...IF IT EVEN ACCUMULATES AT ALL...AS MUCH
BETTER POTENTIAL FOR 1+ INCHES OF WET SNOW WILL FOCUS 50+ MILES
WEST-NORTHWEST OF THE CWA. ALSO...ALTHOUGH NOT EXPECTING THE NEED
FOR A FORMAL WIND ADVISORY...A WELL-DEFINED PRESSURE RISE SURGE
OVERNIGHT COULD EASILY BRING A FEW HOURS OF NEAR-30 MPH SUSTAINED
NORTH WINDS WITH GUSTS TO AROUND 40 MPH...AND THIS HAS BEEN ADDED
TO THE HAZARDOUS WEATHER OUTLOOK. CHANGED LOW TEMPS LITTLE RANGING
FROM MID 30S NORTHWEST TO LOW 40S SOUTHEAST. RAINFALL AMOUNTS
TONIGHT FOR THE MAJORITY OF THE AREA WILL LIKELY AVERAGE UNDER
0.25-INCH...EXCEPT FOR LOCALLY HIGHER THUNDERSTORM-ENHANCED
CORRIDORS.
TURNING TO THE THURSDAY/THURSDAY NIGHT...CONSENSUS OF VARIOUS
MODELS SUGGESTS MOST IF NOT ALL OF THE CWA WILL BE PRECIP-FREE BY
SUNRISE THURSDAY MORNING AS FORCING QUICKLY DEPARTS TO THE EAST.
AS A RESULT...PULLED NEARLY ALL POPS FROM THE MORNING PERIOD...BUT
DID LEAVE A SLIGHT CHANCE OF A LIGHT RAIN/SNOW MIX IN SOME FAR
NORTHERN AREAS THROUGH 15Z TO ACCOUNT FOR THE PRESENCE OF A
QUICKLY DEPARTING MID-LEVEL DEFORMATION ZONE. OTHERWISE...THURS
WILL REMAIN QUITE BREEZY WITH SUSTAINED SPEEDS 20-25 MPH AND
HIGHER GUSTS AS INCREASING SUNSHINE RESULTS IN INCREASED MIXING.
MADE LITTLE CHANGE TO HIGH TEMPS WITH A CHILLY DAY IN STORE
RANGING MID 40S NORTH TO LOW 50S SOUTH. THURS NIGHT...A TRAILING
REINFORCING SHORTWAVE WILL BRING SOME LIGHT SNOW AS CLOSE AS
EXTREME NORTHWEST KS/SOUTHWEST NEB...BUT ONLY PASSING MID LEVEL
CLOUDS ARE EXPECTED LOCALLY AS NORTH WINDS DECREASE. LOWERED LOWS
2-4 DEGREES FROM PREVIOUS FORECAST ESPECIALLY NORTHWEST...NOW
PUTTING MOST AREAS IN THE MID-UPPER 20S WHICH FOR MUCH OF THE AREA
COULD BE THE FIRST HARD FREEZE SINCE OCT. 7TH.
FRIDAY/FRIDAY NIGHT...A DRY AND SEASONABLY CHILLY FORECAST
CONTINUES...ALTHOUGH A FEW MOISTURE-STARVED PASSING SHORTWAVES
COULD BRING A FEW BATCHES OF PASSING MID LEVEL CLOUDS. BREEZES
FRIDAY WILL AVERAGE NO MORE THAN 5-10 MPH AS SURFACE HIGH PRESSURE
SETTLES DIRECTLY OVER THE AREA...AND ONLY MADE A VERY SLIGHT
UPWARD NUDGE TO HIGH TEMPS...WITH NEARLY ALL AREAS TOPPING OUT NO
BETTER THAN MID-UPPER 40S. FRIDAY NIGHT...LOW TEMPS COULD REALLY
BOTTOM OUT IN SOME AREAS OR POSSIBLY BE HELD UP BY PLENTY OF
PASSING MID LEVEL CLOUDS. AS A RESULT...GENERALLY PLAYED CLOSE TO
PREVIOUS FORECAST WITH VALUES SIMILAR TO THURS NIGHT IN THE MID-
UPPER 20S FOR MOST AREAS.
.LONG TERM...STARTING 12Z SATURDAY...A FAIRLY QUIET WEATHER PATTERN
APPEARS TO BE IN STORE FOR THE LOCAL AREA THROUGH THE EXTENDED
PERIODS AS THE LONGWAVE TROUGH MOVING ONSHORE ACROSS THE WEST COAST
THIS MORNING IS EXPECTED TO BEGIN EXITING THE PLAINS BY SATURDAY.
LATEST GLOBAL SCALE MODELS ARE IN GOOD AGREEMENT SWINGING THE AXIS
OF THIS UPPER TROUGH INTO THE OHIO VALLEY BY SUNDAY MORNING...
KEEPING THE LOCAL AREA IN A GENERALLY NORTHWESTERLY FLOW PATTERN
ALOFT THROUGH EARLY NEXT WEEK. WITH NO NOTABLE DISTURBANCES EMBEDDED
IN THIS FLOW...EXPECT DRY CONDITIONS TO PREVAIL ACROSS THE LOCAL
AREA SATURDAY THROUGH TUESDAY. IN FACT...WITH HEIGHTS RISING AHEAD
OF AN UPPER LEVEL RIDGE OF HIGH PRESSURE EXPECTED TO TRANSITION FROM
THE INTERMOUNTAIN WEST INTO THE PLAINS BY TUESDAY...EXPECT A SLOW
WARMING TREND TO START OFF THE NEW WEEK...AS 850MB TEMPS CLIMB
APPROXIMATELY 10C BETWEEN SATURDAY AND TUESDAY. THIS INCREASE IN
TEMPERATURES ALOFT SHOULD ALLOW AFTERNOON TEMPS TO CLIMB FROM THE
40S ON SATURDAY...TO THE LOWER 60S IN SPOTS BY TUESDAY
AFTERNOON...WHICH IS ACTUALLY A FEW DEGREES ABOVE CLIMATOLOGY FOR
LATE OCTOBER. ADDITIONALLY...IF THE CURRENT PATTERN PANS
OUT...CONTINUED PLEASANT AND DRY WEATHER LOOKS PLAUSIBLE FOR
HALLOWEEN...WHICH LIES JUST BEYOND THE EXTENT OF THE CURRENT
FORECAST...WITH HIGH TEMPERATURES POTENTIALLY CLIMBING IN THE MID
60S NEXT WEDNESDAY AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 1242 AM CDT WED OCT 24 2012/
AVIATION...06Z KGRI TAF...GENERALLY POOR AVIATION CONDITIONS
ARE EXPECTED THROUGH THE MORNING HOURS WEDNESDAY AS DENSE FOG HAS
ENCOMPASSED MUCH OF THE REGION EARLY THIS MORNING. EXPECT LIFR
CIGS AND VSBYS TO CONTINUE FOR THE NEXT SEVERAL HOURS IN ADVANCE
OF AN APPROACHING COLD FRONT...WITH SOME IMPROVEMENT POSSIBLE
DURING THE MORNING HOURS AROUND THE PASSAGE OF THIS BOUNDARY. IN
GENERAL...EXPECT A RETURN TO IFR CIGS AND VSBYS NEAR 24/16Z...
WITH CONDITIONS EVENTUALLY BECOMING VFR BY LATE AFTERNOON. WINDS
WILL EVENTUALLY INCREASE OUT OF THE NORTH DURING THE EARLY MORNING
HOURS BEHIND THE FRONT...GUSTING TO 16+KTS THIS AFTERNOON...AND
20+KTS LATER THIS EVENING AS RAPID PRESSURE RISES ARE REALIZED...AS
THE FRONT FINALLY GETS PUSHED SOUTHEAST LATE TONIGHT. KEPT PRECIP
OUT OF THE END OF TAF FOR THE TIME BEING...BUT WILL LIKELY
EVENTUALLY NEED TO ADD A TSRA OR SHRA AROUND OR AFTER 24/06Z IN
SUBSEQUENT TAFS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR NEZ048-049-
061>064-073>077-082>087.
KS...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR KSZ005>007-
017.
&&
$$
SHORT TERM...PFANNKUCH
LONG TERM/AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
205 PM EDT WED OCT 24 2012
.SYNOPSIS...
OFF AND ON SHOWERS WILL CONTINUE TODAY AS A STALLED FRONTAL BOUNDARY
REMAINS IN THE VICINITY. HIGH PRESSURE WILL RULE ON THURSDAY AND
FRIDAY WITH A SOUTHERLY FLOW AND MODERATING TEMPERATURES EXPECTED. A
COLD FRONT WILL MOVE THROUGH FOR THE WEEKEND BRINGING ANOTHER CHANCE
FOR RAIN.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
930 AM UPDATE...
OVERALL FORECAST IN GOOD SHAPE. MUCH OF THE MODEL
GUIDANCE...INCLUDING THE HIGHER RESOLUTION HRRR AND 4KM NAM...ARE
NOT CAPTURING THE RAIN CURRENTLY OVER THE NORTHERN TIER OF PA AND
THE CENTRAL SOUTHERN TIER OF PA. THROUGH THE NEXT 4 HOURS WILL DO
A STRIPE OF LIKELY POPS FROM NEAR ELMIRA SOUTHWEST TO NEAR
BINGHAMTON...DOWN THROUGH SAYRE...MONTROSE...SCRANTON...AND
DINGMANS FERRY. OTHERWISE WITH THE WARM FRONTAL BOUNDARY REMAINING
STALLED OR JUST A SLIGHT JOG NORTH BY LATE TODAY...CHANCE POPS
TODAY LOOK GOOD IN THE GENERAL AREA SEEING RAIN NOW. BEST CHANCE
FOR A DRY DAY WILL BE ACROSS THE FAR NORTH.
3 AM UPDATE... WMFNT HAS WASHED OUT JUST SOUTH OF THE FA
EXTNDG ACRS CNTRL PA AND TWD PHILLY PA. VORT MAX IS ROTATING ALONG
THE STATE LINE AND DROPPING SOUTH AND EAST AS THE NIGHT WEARS ON.
THIS IS RESULTING IN -SHRAS RIGHT ALONG THE TWIN TIERS. WITH VRY
MINIMAL DWPT DEPRESSIONS CWA-WIDE FOG HAS DEVELOPED ACRS CNTRL NY
AND NEPA. LOCALES IN THE HIGHER TERRAIN ARE DENSE AT TIMES WITH
AVG VSBYS GNRLY RANGING FM 1/2 TO 3 MILES. THUS HV ISSUED SPS TO
COVER THIS AS A DENSE FOG ADVISORY SEEMS TO BE OVERKILL.
AS THE DAY WEARS ON SCTD SHOWERS WL SLOWLY COME TO AN END BY LATE
AFTN. TO ACCNT FOR ANY -SHRAS THAT MAY POP UP HV GNRLY GONE 30-40
POPS IN MOIST ENVIRONMENT. WL BE HARD-PRESSED TO BREAK OUT IN MOIST
ATMOSPHERE AND CANNOT FORESEE MAX TEMPS RISING INTO THE MAV/MET
GUIDANCE RANGE OF THE MID-60S, ESPECIALLY AFTER YDAS POOR
PERFORMANCE UNDER CLDY CONDS. THUS HV GONE WITH HRLY TEMPS FM THE
LAV AND HV LOWERED THESE MAX TEMPS 1-2 DEGREES WITH PLACES IN THE
SOUTH AND WEST IN THE LWR 60S AND ELSEWHERE RMNG IN THE U50S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
3 AM UPDATE... ISOLD SHOWERS WL CONT THRU MIDNIGHT BFR
TRANSITIONING TO PATCHY DRIZZLE ACRS THE FAR SRN ZONES. SFC HIPRES
OVR WRN QUEBEC WL BUILD SOUTH INTO NEW ENGLAND WITH SRLY SFC FLOW
RESULTING IN OROGRAPHIC LIFT. THO QPF AMNTS WL BE MINIMAL THRU 12Z
THURSDAY WITH ONLY A FEW HUNDREDTHS OF AN INCH EXPECTED. THO SRLY
FLOW DOES NOT EXTND MUCH ABV THE SFC TO ANY SIGNIFICANT DEPTH ENUF
MOISTURE WL BE PRESENT DUE TO THE WASHED OUT WMFNT TO KEEP DRIZZLE
GOING THRU PORTIONS OF THE DAY ON THUR.
BY THUR AFTN, SKIES WL CLR FM WEST TO EAST AND WITH SRLY FLOW ACRS
THE REGION H8 TEMPS WL SOAR TO BTWN 12C TO 14C. THIS WL YIELD HIGHS
IN THE LWR 70S FOR THE LK PLAIN WITH SERN ZONES STUCK IN THE 60S
UNDER CLD CVR.
AS HIPRES BUILDS EAST OF NEW ENGLAND ON FRIDAY OCCLUDED FNT WL APPCH
FM THE WEST. NAM BRINGS PCPN INTO WRN AND CNTRL ZONES BY 00Z SAT,
WHILE EURO IS SLIGHTLY DELAYED BRINGING PCPN JUST INTO WRN NY BY
THIS TIME, GFS IS THE SLOWEST WITH QPF STILL BACK IN NWRN OH. THUS
WL MAKE VRY FEW CHGS TO FRI/FRI NGT FCST WITH SLGT CHC POPS EXPECTED
THRU 12Z SAT.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
CONTD WITH MAJOR UNCERTAINTY IN THE LONG TERM WITH THE MODELS
STILL TRYING TO RESOLVE SANDY AND THE WEATHER WITH THE STORM. 12Z
OPERATIONAL GFS NOW DOES INDEED CAPTURE THE TROPICAL STORM AND SLAM
IT INTO THE NEW ENGLAND CST ONLY TO STALL IT OVER THE NRN
ADIRONDACKS WED. PRVS 00Z ECMWF DOWNRIGHT SCARY...ESP FOR CSTL NY/NJ
WITH THE STORM LEFT TURNING A CPL HNDRD MILES FURTHER SOUTH INTO
CNTRL NJ BEFORE STALLING AS EARLY AS TUE. GFS ENSEMBLE MEMBERS
HAVE TRENDED TWRD A MORE WWRD TRACK...SO THE BOTTOMLINE IT IS
LOOKING MORE AND MORE LIKE THIS SIGNIFICANT STORM WILL BE
IMPACTING CNTRL NEW YORK AND NE PENNSYLVANIA IN THE XTNDD PD.
SO...THE MILLION DOLLAR QUESTION IS WHAT WILL THAT IMPACT BE.
BOTH THE OPERATIONAL GFS AND ECMWF INDICATE THAT ANY "PRE" PCPN
WLD REMAIN MSTLY WEST OF THE FCST AREA ON LATE SUN AND EARLY
MON...GOOD NEWS FOR FLOODING CNCRNS FOR SURE. ECMWF THEN...WITH
IT/S SRN TRACK...WLD THEN PUT MUCH OF THE FCST AREA UNDER AND AREA
OF POTENTIALLY HEAVY RAIN FROM MON INTO EARLY TUE...ESP IN THE
UPSLOPE AREAS OF THE CATS AND POCONOS...AS THE PERSISTENT SELY
FLOW CONTS.
OTR DFRNCS INCLUDE THE PSBLTY OF ANY SNOW...AND WITH THE GFS/S
MORE NRN TRACK...PARTS OF THE FCST AREA...PARTICULARY ALONG AND
SOUTH OF THE NY/PA BRDR...MAY BE COLD ENUF LATE IN THE PD FOR SOME
FRZN PCPN. ALSO...MORE DIRECT TRACK OF THE ECMWF BRINGS THE PSBLTY
OF HIER WINDS AS EARLY AS MON...WHILE THE GFS IS AT LEAST 24 HRS
LTR.
FOR THE GRIDS...DECIDED THERE WAS TOO MUCH UNCERTAINTY TO STRAY
MUCH FROM THE HPC GUID...WHICH SEEMED TO BE A NICE COMPROMISE OF
THE DFRNT SOLNS.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
STALLED FNTL BNDRY WILL KEEP LOW CLDS AND VSBY WITH IFR CONDS THRU
THE TAF PD. TEMPOPRARY XCPTN IS AT AVP WHERE CLRG HAS BROKEN
OUT...BUT AS NGT FALLS...LL MOISTURE AND A VERY STABLE SNDG WILL
BRING LOW CLDS BACK TO THE STATION. ELSEWHERE...SOME BRIEF IMPRVMT
PSBL THIS AFTN AS LIMITED HHTG THRU A FEW BRLKS IN THE CLDS HELPS
TO MIX UP SOME OF THE CIGS AND VSBYS. TNGT...BNDRY REMAINS IN
PLACE ANS WITH PLENTY OF MOSITURE...XPCT CIGS AND VSBYS TO ONCE
AGAIN LWR TO LIFR IN SOME PLACES...ESP THE HIER STATIONS LIKE BGM
AND ITH. SOME IMPRVMT AGAIN AFT 12Z THU AS THE MODELS SOME DRYING
OF THE LL ALLOWING FOR SLOW INCREASES IN CIGS AND VSBYS.
LGT SELY FLOW ALONG THE BNDRY AND THRU THE AREA WILL CONT FOR THE
TAF PD.
OUTLOOK...
THU AFTN...IMPROVING TO VFR.
FRI...MAINLY VFR.
SAT/SUN/MON...MVFR/IFR POSSIBLE IN SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN
NEAR TERM...HEDEN/PVN
SHORT TERM...PVN
LONG TERM...DGM
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
941 AM EDT WED OCT 24 2012
.SYNOPSIS...
OFF AND ON SHOWERS WILL CONTINUE TODAY AS A STALLED FRONTAL BOUNDARY
REMAINS IN THE VICINITY. HIGH PRESSURE WILL RULE ON THURSDAY AND
FRIDAY WITH A SOUTHERLY FLOW AND MODERATING TEMPERATURES EXPECTED. A
COLD FRONT WILL MOVE THROUGH FOR THE WEEKEND BRINGING ANOTHER CHANCE
FOR RAIN.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
930 AM UPDATE...
OVERALL FORECAST IN GOOD SHAPE. MUCH OF THE MODEL
GUIDANCE...INCLUDING THE HIGHER RESOLUTION HRRR AND 4KM NAM...ARE
NOT CAPTURING THE RAIN CURRENTLY OVER THE NORTHERN TIER OF PA AND
THE CENTRAL SOUTHERN TIER OF PA. THROUGH THE NEXT 4 HOURS WILL DO
A STRIPE OF LIKELY POPS FROM NEAR ELMIRA SOUTHWEST TO NEAR
BINGHAMTON...DOWN THROUGH SAYRE...MONTROSE...SCRANTON...AND
DINGMANS FERRY. OTHERWISE WITH THE WARM FRONTAL BOUNDARY REMAINING
STALLED OR JUST A SLIGHT JOG NORTH BY LATE TODAY...CHANCE POPS
TODAY LOOK GOOD IN THE GENERAL AREA SEEING RAIN NOW. BEST CHANCE
FOR A DRY DAY WILL BE ACROSS THE FAR NORTH.
3 AM UPDATE... WMFNT HAS WASHED OUT JUST SOUTH OF THE FA
EXTNDG ACRS CNTRL PA AND TWD PHILLY PA. VORT MAX IS ROTATING ALONG
THE STATE LINE AND DROPPING SOUTH AND EAST AS THE NIGHT WEARS ON.
THIS IS RESULTING IN -SHRAS RIGHT ALONG THE TWIN TIERS. WITH VRY
MINIMAL DWPT DEPRESSIONS CWA-WIDE FOG HAS DEVELOPED ACRS CNTRL NY
AND NEPA. LOCALES IN THE HIGHER TERRAIN ARE DENSE AT TIMES WITH
AVG VSBYS GNRLY RANGING FM 1/2 TO 3 MILES. THUS HV ISSUED SPS TO
COVER THIS AS A DENSE FOG ADVISORY SEEMS TO BE OVERKILL.
AS THE DAY WEARS ON SCTD SHOWERS WL SLOWLY COME TO AN END BY LATE
AFTN. TO ACCNT FOR ANY -SHRAS THAT MAY POP UP HV GNRLY GONE 30-40
POPS IN MOIST ENVIRONMENT. WL BE HARD-PRESSED TO BREAK OUT IN MOIST
ATMOSPHERE AND CANNOT FORESEE MAX TEMPS RISING INTO THE MAV/MET
GUIDANCE RANGE OF THE MID-60S, ESPECIALLY AFTER YDAS POOR
PERFORMANCE UNDER CLDY CONDS. THUS HV GONE WITH HRLY TEMPS FM THE
LAV AND HV LOWERED THESE MAX TEMPS 1-2 DEGREES WITH PLACES IN THE
SOUTH AND WEST IN THE LWR 60S AND ELSEWHERE RMNG IN THE U50S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
3 AM UPDATE... ISOLD SHOWERS WL CONT THRU MIDNIGHT BFR
TRANSITIONING TO PATCHY DRIZZLE ACRS THE FAR SRN ZONES. SFC HIPRES
OVR WRN QUEBEC WL BUILD SOUTH INTO NEW ENGLAND WITH SRLY SFC FLOW
RESULTING IN OROGRAPHIC LIFT. THO QPF AMNTS WL BE MINIMAL THRU 12Z
THURSDAY WITH ONLY A FEW HUNDREDTHS OF AN INCH EXPECTED. THO SRLY
FLOW DOES NOT EXTND MUCH ABV THE SFC TO ANY SIGNIFICANT DEPTH ENUF
MOISTURE WL BE PRESENT DUE TO THE WASHED OUT WMFNT TO KEEP DRIZZLE
GOING THRU PORTIONS OF THE DAY ON THUR.
BY THUR AFTN, SKIES WL CLR FM WEST TO EAST AND WITH SRLY FLOW ACRS
THE REGION H8 TEMPS WL SOAR TO BTWN 12C TO 14C. THIS WL YIELD HIGHS
IN THE LWR 70S FOR THE LK PLAIN WITH SERN ZONES STUCK IN THE 60S
UNDER CLD CVR.
AS HIPRES BUILDS EAST OF NEW ENGLAND ON FRIDAY OCCLUDED FNT WL APPCH
FM THE WEST. NAM BRINGS PCPN INTO WRN AND CNTRL ZONES BY 00Z SAT,
WHILE EURO IS SLIGHTLY DELAYED BRINGING PCPN JUST INTO WRN NY BY
THIS TIME, GFS IS THE SLOWEST WITH QPF STILL BACK IN NWRN OH. THUS
WL MAKE VRY FEW CHGS TO FRI/FRI NGT FCST WITH SLGT CHC POPS EXPECTED
THRU 12Z SAT.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
4 AM WED UPDATE... ONLY MINOR TWEAKS MADE TO THE EXTENDED GRIDS
ATTM...AS A FAIR AMT OF UNCERTAINTY EXISTS WITHIN A POTENTIALLY ACTIVE
WX PD.
THE MAIN EMPHASIS CONTS TO BE ON SANDY...AND WHERE SHE TRACKS FROM
LTR THIS WEEKEND INTO NEXT WEEK. THE EC REMAINS NEAR THE WRN EDGE
OF THE GUIDANCE ENVELOPE...TRACKING THE LOW CENTER NWD TO JUST OFF
THE MID-ATL COAST BY MON/EARLY TUE...BEFORE ACTUALLY HOOKING THE
SYSTEM NWWD TO NEAR NY CITY THEREAFTER...AS AN AMPLIFIED UPR-LVL
TROUGH ESSENTIALLY CAPTURES IT. THIS SOLN...UNFORTUNATELY...HAS
BEEN THE MOST CONSISTENT RUN TO RUN OF ALL THE MODELS (GFS REMAINS
FARTHER E...ALTHOUGH THE OPERATIONAL RUN MAY ACTUALLY BE AN
OUTLIER...WITH MANY GFS ENSEMBLE MEMBERS MUCH CLOSER TO THE E
COAST...MORE LIKE THE EC). HPC PREFERENCE APPEARS TO STILL BE WITH THE
MORE CONSISTENT EC AT THIS PT...AND THUS WE`LL KEEP THE CHANCES
FOR RAIN GOING ACRS CNY/NE PA FROM SAT...RIGHT INTO EARLY NEXT
WEEK.
IT NEEDS TO BE EMPHASIZED AGN THAT LOTS OF UNCERTAINTY EXISTS...AS
MODEL TRACK ERRORS CAN BE QUITE LARGE AT SUCH TIME RANGES. SANDY
IS ALSO STILL IN THE CARIBBEAN SEA ATTM...WITH ANY POTENTIAL
IMPACTS IN OUR FA AT LEAST 3-5 DAYS AWAY.
ALL THAT BEING SAID...THOUGH...THERE ARE SYNOPTIC SIGNALS IN OUR
NWP GUIDANCE THAT WOULD IMPLY AN EVENTUAL HEAVY RAIN THREAT FOR THE MID-
ATL AND NERN STATES. THESE INCLUDE A HIGHLY AMPLIFIED PATN FOR
SANDY TO BECOME INCORPORATED INTO (DEEP UPR-LVL TROUGH IN THE
GREAT LKS/OH VLY AND UPR-LVL RIDGE IN THE N ATLANTIC)...A VERY STG
UPR-LVL JET STREAK TO OUR NW (170+ KT...WITH NY/PA IN THE ENTRANCE
RGN)...AND A FRNTL BNDRY/INVERTED TROUGH PRESENT FOR ANY TROP
MOIST TO OVERRUN. GIVEN THE POTENTIALLY DEEP ERLY FETCH FROM THE
VICINITY OF SANDY INTO THE ERN CONUS...AND THE JUST MENTIONED
FRNTL ZN/SFC TROUGH...PRE (PREDECESSOR RAIN EVENT) FORMATION COULD
EVEN BE IN THE CARDS SOMEWHERE ACRS THE ERN STATES...AS SOON AS
LTR SAT/EARLY SUN. TIME WILL CERTAINLY TELL...AND HOPEFULLY WE`LL
SEE IMPROVED MODEL CONSENSUS IN THE COMING DAYS.
WE`LL CONTINUE TO MONITOR THIS SITN CLOSELY...SO STAY TUNED FOR
THE LATEST UPDATES.
PREV DISC... 315 PM UPDATE...
DESPITE DIFFERENCES STILL BETWEEN THE 12Z MODELS
(EURO/CANADIAN/GFS) WITH REGARDS TO SANDY...THE IMPACT ON OUR AREA
AT THE START OF THE EXTENDED PERIOD HAS COME INTO BETTER FOCUS
OVER THE LAST 24 HOURS. THEREFORE THE HIGHEST CONFIDENCE IN THE
EXTENDED WILL BE IN THE SATURDAY THROUGH SUNDAY PERIOD...WHERE A
COLD FRONT ACROSS THE GREAT LAKES WILL GRADUALLY STALL ACROSS OUR
AREA PRODUCING RAIN. HIGH CHANCE POPS FROM HPC LOOK GOOD TO COVER
THIS. WITH THE INCREASED THREAT FOR CLOUDS AND PRECIP...TEMPS
WILL BE MUCH COOLER THAN WHAT WE WILL EXPERIENCE FOR THE END OF
THE WEEK.
MUCH UNCERTAINTY EXISTS FROM SUNDAY NIGHT AND BEYOND...WITH THE
12Z GFS AND CANADIAN STILL WELL OUT TO SEA WITH SANDY...WHILE THE
12Z EURO TAKES SANDY INTO EASTERN LI BY 12Z TUESDAY. HPC GUIDANCE
SEEMS TO LEAN WITH THE EURO FOR OUR AREA WITH HIGH CHANCE POPS
RIGHT THROUGH TUESDAY. AGREE CHANCE POPS SEEM WARRANTED WITH THE EURO
SOLUTION BEING CONSISTENT HOWEVER WITH MOST MODEL GUIDANCE NOT IN
AGREEMENT WITH THE EURO...WILL KNOCK US BACK TO LOW CHANCE DURING
THIS TIME. AGAIN MUCH TOO FAR OUT TO GET MORE SPECIFIC THAN THAT.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
12Z WED UPDATE... RESTRICTIVE CONDS ARE STILL (LOW CIGS/FOG/LGT
RAIN OR DRZL) ANTICIPATED THROUGHOUT MUCH OF THE VALID TAF PD. THE
WORST CONDS SHOULD BE THROUGH 15-16Z (LIFR/IFR AT
KBGM/KITH/KELM/KSYR...WITH MAINLY MVFR AT KRME).
THERE SHOULD BE SOME IMPROVEMENT THIS AFTN...AS CIG BASES/VSBYS
LIFT A LTL BIT. HOWEVER...FOR MOST SITES...ANY PROLONGED PDS OF VFR ARE
UNLIKELY...GIVEN THE DEGREE OF LOW-LVL MOIST...WEAK SFC FLOW...AND
DIMINISHING SUN ANGLE THIS TIME OF YEAR. THE MOST LIKELY SPOT TO
SEE ANY SUSTAINED VFR IS KAVP...WHERE THE MOIST LYR IS PROGGED TO
BE MORE SHALLOW.
SOMEWHAT UNCERTAIN THIS EVE (AFTER 00Z)...AS SOME DETERIORATION COULD
OCCUR AGAIN...INTRODUCING THE PSBLTY OF IFR RE-EMERGENCE. AT THIS
PT...WE FEEL IFR WOULD BE MORE LIKELY THE RESULT OF LWR CIGS...AS
OPPOSED TO RADIATION FOG...GIVEN THE ANTICIPATED LACK OF ANY SIG
CLEARING. THUS...WE HIT IFR CONDS THE HARDEST ON THE HILLTOPS AT
KBGM AND KITH. WE KEPT THE OTHER SITES MVFR FOR THE TIME BEING.
OUTLOOK...
THU...IMPROVING TO VFR...AFTER EARLY MVFR/IFR CIGS...AND PATCHY FOG.
FRI...MAINLY VFR.
SAT/SUN...MVFR POSSIBLE IN SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN
NEAR TERM...HEDEN/PVN
SHORT TERM...PVN
LONG TERM...HEDEN/MLJ
AVIATION...MLJ/MDP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
945 PM EDT THU OCT 25 2012
.SYNOPSIS...
HIGH PRESSURE CENTERED TO OUR NORTHEAST WILL EXTEND DOWN THE MID
ATLANTIC COAST THROUGH FRIDAY. TROPICAL CYCLONE SANDY WILL TRACK
TOWARD THE NORTH OR NORTH NORTHEAST OFF THE SOUTHEAST AND CAROLINA
COAST FRIDAY THROUGH SUNDAY.
&&
.NEAR TERM /THROUGH FRIDAY NIGHT/...
AS OF 945 PM THURSDAY...
OUTSIDE OF SOME THIN CIRRUS FROM THE OUTER BANDS OF HURRICANE SANDY
DRIFTING ACROSS THE SOUTHEAST CWA...SKIES ARE MOSTLY CLEAR FOR MUCH
OF THE AREA. THE DEEP LAYER RIDGE REMAINS CENTERED ALONG THE EAST
COAST...WITH SURFACE HIGH PRESSURE EXTENDING WEST FROM THE ATLANTIC
ACROSS NC. EASTERLY WINDS JUST ABOVE THE SURFACE ARE LEADING TO THE
REDEVELOPMENT OF A MARINE LAYER OVER SOUTHEAST VA AS MOISTURE
ADVECTS SOUTHWEST BELOW AN INVERSION NOTED NEAR 925MB ON THE 00Z
KWAL RAOB. STRATUS SHOULD BEGIN TO SPREAD SOUTHWEST ACROSS THE CWA
AFTER MIDNIGHT..AND HRRR MOISTURE FIELDS SUGGEST THE STRATUS WILL
SPREAD ACROSS ALL BUT THE SOUTHERN PIEDMONT BY 12Z. HAVE ADJUSTED
SKY GRIDS TO BE A LITTLE MORE AGGRESSIVE...WITH ALL BUT THE COUNTIES
BORDERING THE YADKIN MOSTLY CLOUDY BY 12Z. OUTSIDE OF THE
STRATUS...PATCHY FOG IS POSSIBLE UNDER MOSTLY CLEAR SKIES AND NEARLY
CALM CONDITIONS.
TEMPS ARE CURRENTLY IN THE LOW TO MID 60S MOST EVERYWHERE...THOUGH
COOLING WILL SLOW AS THE STRATUS ROLLS IN. THUS...THE CURRENT
FORECAST OF 53-57 LOOKS ON TRACK. -BLS
FOR FRIDAY/FRIDAY NIGHT: WEATHER CONDITIONS SLOWLY START TO
DETERIORATE DURING THIS TIME FRAME. NC IS WITHIN THE MID LEVEL COL
AREA FRIDAY MORNING... WITH RIDGING TO THE ENE AND SW... THE LARGE
POLAR TROUGH TO OUR NW... AND THE APPROACHING CIRCULATION OF SANDY
TO OUR SSE. SANDY`S CENTER IS EXPECTED TO MOVE GENERALLY NORTHWARD
OVER AND THEN NORTH OF THE BAHAMAS THROUGH FRIDAY NIGHT. (PLEASE SEE
THE VERY LATEST OFFICIAL FORECASTS FROM THE NHC REGARDING SANDY.)
ITS LARGE CIRCULATION WILL START TO AFFECT NC FRIDAY NIGHT AS THE
STORM`S APPROACH AGAINST THE NARROWING RIDGE NOSING FROM MAINE INTO
NW NC QUICKLY INCREASES THE MSLP GRADIENT PARTICULARLY OVER SRN AND
ERN NC AS WE HEAD INTO FRIDAY NIGHT. BACKING UP TO FRIDAY... THE
MORNING CLOUDS AND FOG SHOULD VERY SLOWLY LIFT THROUGH THE
MORNING... BUT OVERALL EXPECT VARIABLY TO MOSTLY CLOUDY SKIES FOR
MOST OF THE DAY FROM RALEIGH SOUTH AND EAST... WITH A BIT MORE
SUNSHINE TO THE NW OVER THE TRIAD AREA. TEMPS ARE QUITE TOUGH GIVEN
THAT ANY BREAK IN THE CLOUDS WILL ALLOW FOR POCKETS OF HEATING TO
PUSH TEMPS WELL UP THROUGH THE UPPER 70S GIVEN THICKNESSES THAT ARE
NEARLY 20 METERS ABOVE NORMAL... WHILE LOCALIZED PERSISTENT CLOUD
COVER THROUGHOUT THE DAY WILL HOLD TEMPS DOWN INTO THE LOWER 70S.
WILL GO WITH HIGHS OF 73 NORTH-CENTRAL TO 76-77 SOUTHEAST WITH LOWER
THAN USUAL CONFIDENCE. EXPECT SKIES TO TREND QUICKLY TO OVERCAST
FRIDAY EVENING... BOTH WITH THE PERSISTENT ONSHORE FLOW ENCOURAGING
GREATER AND THICKER STRATUS DEVELOPMENT AREAWIDE... AND FROM
INCREASING MID AND HIGH CLOUDS AS SANDY`S EXHAUST CLOUD SHIELD
APPROACHES FROM THE SSE. CLOUDS MAY ACTUALLY BE THICKEST AND MOST
EXTENSIVE OVER THE WRN PIEDMONT AS THE MOIST EASTERLY LOW LEVEL FLOW
RIDES UP AND OVER THE LINGERING VULNERABLE SURFACE RIDGE CREATING
LOCALLY DEEPER MOIST ISENTROPIC UPGLIDE. WHILE PW VALUES ARE
EXPECTED TO BE TRENDING STEADILY UPWARD... TO 1.25-1.5 INCHES WHICH
IS AT OR ABOVE 150% OF NORMAL... ANY TROPICAL SHOWERS SHOULD BE
PATCHY GIVEN THE LACK OF STRONG FORCING AND LINGERING MID LEVEL DRY
AIR. WILL SLOW DOWN AND SLIGHTLY REDUCE POPS... GOING WITH PRIMARILY
SLIGHT CHANCE POPS AFTER SUNSET. MILD LOWS IN THE UPPER 50S TO LOWER
60S WITH BREEZY CONDITIONS DEVELOPING OVERNIGHT. -GIH
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 255 PM THURSDAY...
MODEL GUIDANCE IN GOOD AGREEMENT WITH THE TRACK OF TROPICAL CYCLONE
SANDY PARALLELING THE SE U.S. COAST THROUGH SUNDAY MORNING. SINCE
SANDY HAS AN EXPANSIVE WIND FIELD...WILL START SEEING AN INCREASE IN
MOISTURE TRANSPORT OFF THE ATLANTIC INTO CENTRAL NC FRIDAY NIGHT
THROUGH SATURDAY NIGHT...ABATING ON SUNDAY. THIS INFLUX OF MOISTURE
COUPLED WITH CONVERGENCE ALONG A 700 MB TROUGH OVER THE COASTAL
PLAIN AND INCREASING UPPER DIVERGENCE ALOFT SUPPLIED BY A
STRENGTHENING UPPER JET OVER THE EASTERN GREAT LAKES SUGGEST
CATEGORICAL POPS NEEDED FOR AREAS OF CENTRAL NC...BASICALLY ALONG
AND EAST OF I-95...SATURDAY AFTERNOON INTO EARLY SUNDAY. WILL LIKELY
SEE AREAS OF LIGHT RAIN DEVELOP PRIOR TO DAYBREAK IN THE FAR
EAST...AND MORE SO DURING THE MORNING HOURS SATURDAY BEFORE THE
ABOVE PARAMETERS COME TOGETHER TO CAUSE WIDESPREAD RAIN ASSOCIATED
WITH SANDY. CURRENTLY ADVERTISING RAINFALL AMOUNTS SATURDAY UNTIL
EARLY SUNDAY ALONG AND EAST OF THE I-95 CORRIDOR BETWEEN 1-2 INCHES.
THIS MAY BE CONSERVATIVE AS 00Z ECMWF SUGGEST TOTALS CLOSER TO 3
INCHES. OVER THE PIEDMONT....EXPECT A DEFINITIVE DECREASE IN POPS
BEYOND THE TRIANGLE AREA AS MOISTURE WILL NOT BE AS DEEP AND LIFT
NOT AS STRONG OVER THE WESTERN AND SOUTHERN PIEDMONT.
STILL...OVERCAST SKIES AND BLUSTERY NLY WINDS AND SPOTS OF RAIN WILL
MAKE IT A RAW PERIOD.
AS SANDY MOVES NWD OFFSHORE OF SC-NC LATE SATURDAY THROUGH
EARLY SUNDAY...EXPECT TO SEE AN INCREASE IN THE WINDS...ESPECIALLY
AFTER MIDNIGHT SATURDAY NIGHT WHEN SANDY MAKES ITS CLOSEST APPROACH
TO THE NC COAST (THOUGH STILL QUITE A DISTANCE OFFSHORE). POPULATED
THE WIND GRIDS WITH TCM WINDS FROM THE LATEST NHC TCM PRODUCT THEN
USED A REDUCTION FACTOR OF 30 PERCENT DUE TO SURFACE FRICTION. GUSTS
ACHIEVED BY UTILIZING RESEARCH CURRENTLY BEING CONDUCTED BY THE
C*STAR INITIATIVE (COLLABORATION BETWEEN NWS AND LOCAL
UNIVERSITIES). CURRENTLY EXPECT MAX GUSTS IN OUR FAR EASTERN COASTAL
PLAIN COUNTIES EARLY SUNDAY MORNING 30-33KTS. WHILE CRITERIA WILL
LIKELY NOT BE MET...MAY STILL NEED A WIND ADVISORY BY SUNDAY AS
CONTINUED SUSTAINED WINDS AND AN INCREASINGLY MOIST/SATURATED TOP
SOIL MAY LEAD TO DOWNED TREES AND POWER OUTAGES.
MODEL GUIDANCE IN RELATIVELY GOOD AGREEMENT SUNDAY THROUGH SUNDAY
NIGHT...TAKING SANDY MORE TO THE NE IN RESPONSE TO A S/W ROUNDING
THE BASE OF A DEEP UPPER TROUGH OVER THE GREAT LAKES-OH VALLEY. DID
NOTE THAT THE ECMWF IS ABOUT 20-25MB DEEPER THAN THE GFS AND REMAINS
CLOSER TO THE COAST. THIS NE JOG OF SANDY SHOULD ALLOW THE RAIN AXIS
TO SHIFT MORE TO THE N NE ON SUNDAY. THUS SHOULD SEE RAIN
INTENSITY/COVERAGE BEGIN TO DROP OFF OVER OUR COASTAL PLAIN
COUNTIES...ESPECIALLY BY AFTERNOON. STILL EXPECT WINDS TO REMAIN
QUITE BREEZY DUE TO THE STRENGTH OF SANDY AND A STRONG CANADIAN HIGH
OVER ONTARIO. SUSTAINED WINDS 15-20KTS PROBABLE WITH GUSTS WELL INTO
THE 20S.
TEMPS THROUGH THE PERIOD WILL UNDERGO A COOLING TREND. MAX TEMPS
SATURDAY MAINLY IN THE 60S TO AROUND 70...COOLING INTO THE UPPER 50S
AND 60S SUNDAY. MIN TEMPS SATURDAY NIGHT MAINLY IN THE 50S...COOLING
INTO THE LOW-MID 40S BY EARLY MONDAY.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 250 PM THURSDAY...
SANDY WILL BE THE DOMINATE WEATHER FEATURE THIS PERIOD. MODEL
GUIDANCE STILL OFFERING VARYING SOLUTIONS. ECMWF HAS BEEN THE MOST
CONSISTENT WHILE THE GFS HAS SHOWN AN OVERALL TREND TOWARD THE
ECMWF. THUS WILL LEAN HEAVILY ON THE ECMWF THROUGH THE PERIOD.
S/W IN THE NORTHERN STREAM THAT INITIALLY PUSHES SANDY TO THE NE
WILL EVENTUALLY DRAW SANDY BACK TO THE NW AS IT ATTAINS A NEGATIVE
TILT. THE ECMWF MAKES THIS TURN A LOT SOONER/SHARPER COMPARED TO
THE GFS. THE TRUTH MAY LIE SOMEWHERE IN BETWEEN.
WITH SANDY PROJECTED TO LIE TO OUR NE-N...EXPECT CONTINUED WNW FLOW
ACROSS OUR REGION. DEEP CYCLONIC CURVATURE WILL LIKELY MAINTAIN
CLOUDINESS AND POSSIBLY PATCHES OF LIGHT RAIN OVER OUR FAR N-NE
COUNTIES MONDAY THROUGH EARLY TUESDAY. FARTHER SOUTH...DOWNSLOPE
COMPONENT OF THE LOW-MID LEVEL WINDS SHOULD AID TO SCOUR OUT THE
MOISTURE AND LEAD TO CLEARING SKIES. LOW LEVEL FLOW WILL ALSO
ADVECT MUCH COOLER AIR INTO CENTRAL NC. LOW LEVEL THICKNESSES
TUESDAY MORNING CLUSTER AROUND 1298-1303M...AND 1290-1295M WEDNESDAY
MORNING. HISTORICALLY...THESE VALUES CLUSTER IN THE UPPER 20S TO
AROUND 30. STRONG MIXING AND POSSIBILITY OF CLOUDINESS SHOULD KEEP
TEMPS UP A BIT. MAY SEE BETTER POTENTIAL FOR A LIGHT FREEZE
WEDNESDAY MORNING IN SECTIONS OF THE PIEDMONT. OTHERWISE WITH
THICKNESSES 30-35M BELOW NORMAL...EXPECT MAX TEMPS 10-15 DEGREES
BELOW NORMAL MONDAY-WEDNESDAY WITH SOME MODIFICATION BY THURSDAY.
AFTERNOON TEMPS IN THE 50S EXPECTED FOR MOST OF NEXT WEEK.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
AS OF 745 PM THURSDAY...
24 HOUR TAF PERIOD:
VFR CONDITIONS ARE EXPECTED TO CONTINUE THIS EVENING. HOWEVER... AN
INCREASE IN ATLANTIC MOISTURE WILL ALLOW FOR THE DEVELOPMENT OF
MVFR/IFR FOG AND/OR LOW STRATUS AT ALL TAF SITES AFTER MIDNIGHT...
WITH POSSIBLY SOME LIFR CONDITIONS ACROSS THE EASTERN TAF SITES
(KRDU/KFAY/KRWI). CIGS WILL BE SLOW TO LIFT AND BREAK UP FRIDAY
MORNING (WITH VFR VISBYS EXPECTED AT MOST AREAS BY 13Z)... THUS
EXPECT BKN CIGS AT ALL SITES TO BE MVFR FROM 15Z UNTIL NEAR 18Z...
WITH A TREND TOWARD VFR CIGS THEREAFTER.
OUTLOOK:
AVIATION CONDITIONS ARE EXPECTED TO DETERIORATE AS WHAT IS NOW
HURRICANE SANDY STARTS TO MOVE FROM THE BAHAMAS NORTHWARD OFF THE
SOUTHEAST COAST THROUGH FRIDAY NIGHT... THEN NORTHEASTWARD OFF THE
CAROLINA COAST SATURDAY THROUGH SUNDAY. MVFR/IFR CONDITIONS ARE
EXPECTED TO DOMINATE AT ALL SITES STARTING LATE FRIDAY NIGHT. THE
MOST ADVERSE AVIATION CONDITIONS WILL OCCUR FROM MIDDAY SATURDAY
THROUGH AT LEAST SUNDAY NIGHT... ALTHOUGH DURATION OF ADVERSE
CONDITIONS WILL DEPEND ON THE EVENTUAL TRACK OF SANDY. THE HIGHEST
CONFIDENCE IN POOR AVIATION WEATHER IS AT KRWI/KFAY WHERE HEAVY RAIN
IS POSSIBLE... AND THIS RAIN MAY EXPAND AS FAR WEST AS KRDU. STRONG
GUSTY WINDS FROM THE NNE ARE LIKELY AREAWIDE BUT ESPECIALLY AT
KRDU/KRWI/KFAY... AND LOW LEVEL WIND SHEAR AND/OR SIGNIFICANT
MECHANICAL TURBULENCE IS ALSO POSSIBLE. VFR CONDITIONS ARE EXPECTED
TO RETURN MONDAY... HOWEVER WINDY CONDITIONS MAY PERSIST.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD/BLS
SHORT TERM...WSS
LONG TERM...WSS
AVIATION...BSD/HARTFIELD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
249 PM CDT WED OCT 24 2012
.SHORT TERM...UNSEASONABLY COLD RIDGE OF HIGH PRESSURE FROM
EASTERN MONTANA TO WESTERN MINNESOTA. EXPANSIVE CLOUD SHIELD IN
DEEP CYCLONIC FLOW ALOFT. BAND OF VERY LIGHT PRECIPITATION
SOUTHEAST COUNTIES WITH NO MEASUREABLE REPORTS AT THIS TIME AND
LITTLE SHOWING UP ON REGIONAL WEBCAMS. LOWERED POPS OVER THE
SOUTHEAST FOR THE EVENING HOURS. BELOW NORMAL TEMPERATURES WILL
CONTINUE TONIGHT AND WEDNESDAY.
.LONG TERM...SATURDAY THROUGH WEDNESDAY...
THE HIGHLIGHT OF THE EXTENDED FORECAST WILL BE CONTINUED BELOW
NORMAL TEMPERATURES THROUGH THE WEEKEND.
AS HAS BEEN THE TREND WITH GOOD CONTINUITY...BELOW NORMAL
TEMPERATURES WITH HIGHS GENERALLY IN THE 30S WILL BEGIN THE EXTENDED
FORECAST PERIOD AND CONTINUE THROUGH THE WEEKEND UNDER CYCLONIC
NORTHWEST FLOW ALOFT. THEREAFTER...THE 12 UTC GUIDANCE CONSENSUS IS
TO MODERATE TEMPERATURES THROUGH NEXT WEEK AS BROAD UPPER LEVEL
RIDGE PROPAGATES INTO THE WESTERN AND CENTRAL CONUS. THAT
SAID...UNCERTAINTY DOES EXISTS IN HOW FAST THIS RIDGE WILL BE ABLE
TO BE PROPAGATE INTO THE NORTHERN PLAINS DUE TO DOWNSTREAM
INTERACTIONS WITH THE POTENTIAL LARGE STORM SYSTEM FOR THE EAST
COAST NEXT WEEK.
&&
.AVIATION...
THE SHORT TERM GUIDANCE SUITE HAS HAD A BIT OF TROUBLE HANDLING THE
LOW LEVEL STRATUS TODAY...AND WILL FOLLOW CLOSER TO THE HRRR WHICH
APPEARS TO HAVE THE MOST ACCURATE DEPICTION AS OF 19 UTC.
KISN...KDIK...KBIS AND POSSIBLY KMOT MAY BREAK OUT OF THE STRATUS
TEMPORARILY LATE THIS AFTERNOON AND EARLY EVENING. HOWEVER...DO
EXPECT THE STRATUS TO REDEVELOP ESPECIALLY AFTER THE 03-04 UTC
TIMEFRAME...WITH MVFR CEILINGS THE LIKELY FLIGHT CATEGORY. FLURRIES
ARE ALSO POSSIBLE OVERNIGHT AT KISN AND KMOT...HOWEVER...SIGNIFICANT
RESTRICTIONS TO VISIBILITY ARE NOT EXPECTED.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...HW
LONG TERM....AYD
AVIATION...AJ
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1100 PM CDT THU OCT 25 2012
.DISCUSSION.../ISSUED AT 926 PM CDT/
CLOUD COVER CONTINUES TO BE VERY EXTENSIVE ACROSS THE ENTIRE PLAINS
AND WITH LOW LEVEL WINDS STAYING FROM THE NW ALL NIGHT...NOT SURE
HOW THEY WILL DISAPPEAR. THEREFORE INCREASED SKY COVER ALL NIGHT TO
A CLOUDY OR MOSTLY CLOUDY...AND THEN DECREASED THE CLOUD COVER ON
FRIDAY. THERE IS SOME PATCHY CLEARING NOTED ACROSS SMALL PARTS OF
OUR SOUTHERN FORECAST AREA...NEAR YANKTON AND SIOUX CITY. BUT RIGHT
NOW THAT AREA OF PARTIAL CLEARING LOOKS LIKE IT IS IN NO HURRY TO
EXPLODE INTO A MAJOR CLEARING SCENARIO. SO WITH THE INCREASE IN
CLOUDS...RAISED LOW TEMPS A COUPLE OF CATEGORIES BUT EVEN THESE LOWS
MAY BE TOO COLD. UPDATES ARE ALREADY OUT.
&&
.AVIATION.../FOR THE 06Z TAF ISSUANCE/
VFR IS NOW EXPECTED THROUGH THE FORECAST PERIOD...OR THROUGH 27/06Z.
MODELS CONTINUE TO DO A POOR JOB OF HANDLING SHALLOW MOIST LAYER.
SUSPECT IT WILL BREAK UP SOME BY THE 12Z-15Z TIME PERIOD BUT MAY
PARTIALLY COME BACK AGAIN ACCORDING TO LATEST NAM/NAM12. PROBABLY
BETTER CLEARING BY 27/00Z. IN ANY EVENT LOOKS LIKE TO MANY CLOUDS
AND TOO MUCH OF A LINGERING NORTHWEST BREEZE FOR THE EARLY MORNING
FOG WE HAD MENTION OF EARLIER.
&&
.PREV DISCUSSION.../ISSUED AT 257 PM CDT/
PRECIPITATION HAS ENDED ACROSS THE ENTIRE CWA LATE THIS
AFTERNOON...LEAVING BEHIND A BROAD AREA OF STRATUS OVER THE REGION.
THESE CLOUDS WILL BE THE MAIN CHALLENGE FOR THE SHORTER TERM
PERIOD...WITH MODELS NOT HANDLING THE LOW CLOUDS WELL. RUC LOOKS TO
BE THE BEST WITH THE LOW LEVEL RH FIELD...AND KEEPS THE STRATUS OVER
OUR AREA THROUGH AT LEAST THE EARLY EVENING. AS HIGH PRESSURE BUILDS
INTO THE REGION FROM THE WEST OVERNIGHT...A LESSENING SURFACE
GRADIENT WILL ALLOW WINDS TO COME DOWN BY EARLY EVENING. WENT ON THE
LOW SIDE OF GUIDANCE WITH REGARD TO LOWS TONIGHT...GENERALLY UPPER
TEENS TO LOWER 20S...WITH RELATIVELY LIGHT WINDS...SOME POSSIBLE
SNOW COVER IN SOME AREAS...AND BANKING ON CLOUDS BEGINNING TO BREAK
UP OVERNIGHT. IF CLOUDS PERSIST...IT MAY NOT GET AS COLD AS
CURRENTLY IN THE FORECAST. ANOTHER CHALLENGE WILL BE WHETHER ANY FOG
IS ABLE TO DEVELOP TOWARD FRIDAY MORNING. WHILE NOT AN IDEAL SET UP
WITH LIGHT NORTHWESTERLY WINDS...THINKING IS IF CLOUDS CLEAR OUT AND
WINDS DROP OFF...IN CONJUNCTION WITH ABUNDANT NEAR SURFACE MOISTURE
FROM RECENT RAINFALL/SNOW MELT...FOG WILL DEVELOP IN SOME AREAS. DID
NOT INCLUDE IN THE FORECAST AT THIS POINT...HOWEVER EVENING SHIFT
MAY UPDATE IF IT LOOKS MORE LIKELY.
FRIDAY LOOKS TO BE ANOTHER COOL DAY WITH THE CENTER OF THE HIGH
PRESSURE SLIDING OVERHEAD BY AFTERNOON. THERMAL PROFILES ACTUALLY
COOL A BIT OVER TODAY...THOUGH MODELS HINT AT SOME MID CLOUDS
STREAMING INTO OUR WEST...THERE WILL GENERALLY BE MORE SUN THAN
TODAY WITH HIGHS REACHING INTO UPPER 30S TO LOWER 40S. /JM
FRIDAY NIGHT WILL SEE A WEAK RIDGE OF HIGH PRESSURE MOVE ACROSS THE
AREA...LOCATED NEAR NORTHWEST IOWA BY 12Z SATURDAY. TO THE WEST
SOUTHERLY FLOW AS WELL AS CLOUD COVER WILL INCREASE AS A SHORTWAVE
MOVES INTO THE NORTHERN AND CENTRAL ROCKIES. THIS WILL MAKE FOR
TRICKY LOW TEMPERATURES FORECASTING. WILL LEAN A LITTLE MORE TOWARD
THE CONSMOS IN NORTHWEST IA WHERE WINDS WILL BE LIGHTEST AND CLOSER
TO THE CONSRAW IN CENTRAL SD WHERE WINDS AND CLOUDS WILL LIKELY KEEP
TEMPERATURES A LITTLE MILDER.
LATE SATURDAY AFTERNOON AND SATURDAY NIGHT WILL PROVE TO BE THE NEXT
CHANCE FOR PRECIPITATION. THERE ARE SOME DIFFERENCES AMONGST THE
MODELS LEADING TOWARDS LOWER CONFIDENCE IN A SOLUTION. THE GFS IS
THE MOST BOISTEROUS LEAVING COLDER AIR IN PLACE AND BRINGING HEAVIER
QPF AMOUNTS TO THE NORTHERN CWA. THE NAM IS MUCH WARMER IN THE LOWER
LEVELS THAN THE GFS WHILE THE ECMWF IS A LITTLE BIT WARMER. BOTH
MODELS WOULD LIKELY SUPPORT SNOW HOWEVER AS THE LOW LEVELS ARE
FAIRLY DRY AND WOULD EASILY SWITCH TO SNOW. SREF SOUNDINGS ALL OVER
THE PLACE DURING THIS TIME FRAME AS WELL. DYNAMICALLY THERE IS
SUPPORT FOR SOME PRECIPITATION WITH ICE PROCESSES LIKELY AS THE -12
TO -18 DEGREE C LAYER IS FROM ABOUT 9000 TO 15000 FEET AND THERE
WOULD LIKELY BE A LITTLE BIT OF FRONTAL FORCING AROUND THIS LAYER.
HOWEVER...FRONTAL FORCING WEAK AND WAVE NOT VERY WELL DEFINED SO
BELIEVE THAT THE NAM AND GFS OVERDOING QPF AMOUNTS IN THE THIRD TO
HALF AN INCH RANGE. THE MUCH STRONGER AND BETTER DEFINED SYSTEM THAT
JUST MOVED THROUGH TODAY BARELY PRODUCED AMOUNTS THIS HIGH SO WILL
LOWER BY ABOUT TWO THIRDS. WILL INCREASE POPS INTO THE LIKELY
CATEGORY SATURDAY NIGHT ALONG THE HIGHWAY 14 CORRIDOR HOWEVER AS
SOME MEASURABLE SNOWFALL LOOKS POSSIBLE. WILL KEEP HIGHS THE COOLEST
OVER THE NORTHERN CWA WHERE A MIX OF POTENTIALLY THICKER CLOUD COVER
AND COOLER LOW LEVEL THERMAL FIELD WHILE THE SOUTH COULD MIX JUST A
BIT WITH A SOUTHERLY COMPONENT. LOOKING AT LOWER 40S NORTH TO NEAR
50 SOUTH.
MOST OF THE SNOWFALL WILL BE EAST OF THE AREA ON SUNDAY MORNING WITH
GRADUALLY CLEARING SKIES THROUGH THE DAY. WINDS WILL NOT BE VERY
STRONG SO COOL HIGH TEMPERATURES IN THE MID 40S TO AROUND 50 WILL
NOT FEEL TOO BAD.
IN THE LATTER PERIODS(MON/THU)...NOT MUCH CHANGE IN THIS PERIOD AS
MODELS CONTINUE TO CONVERGE ON THE ECMWF SOLUTION. WHICH HAS BEEN
VERY CONSISTENT THIS WEEK. BASICALLY LOOKING AT A RIDGE OF HIGH
PRESSURE AT THE SURFACE VARYING FROM ABOUT THE BIG SIOUX RIVER
VALLEY EAST INTO WESTERN MINNESOTA. THIS WILL KEEP COOL CONDITIONS
IN PLACE BUT WINDS WILL LIKELY REMAIN FAIRLY CALM. THE WESTERN CWA
WILL SEE THE BEST CHANCE FOR ABOVE NORMAL TEMPERATURES WHILE
SOUTHWEST MINNESOTA WILL HAVE THE BEST CHANCE AT NORMAL TO A BIT
BELOW NORMAL TEMPERATURES. /08
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
926 PM CDT THU OCT 25 2012
.DISCUSSION.../ISSUED AT 926 PM CDT/
CLOUD COVER CONTINUES TO BE VERY EXTENSIVE ACROSS THE ENTIRE PLAINS
AND WITH LOW LEVEL WINDS STAYING FROM THE NW ALL NIGHT...NOT SURE
HOW THEY WILL DISAPPEAR. THEREFORE INCREASED SKY COVER ALL NIGHT TO
A CLOUDY OR MOSTLY CLOUDY...AND THEN DECREASED THE CLOUD COVER ON
FRIDAY. THERE IS SOME PATCHY CLEARING NOTED ACROSS SMALL PARTS OF
OUR SOUTHERN FORECAST AREA...NEAR YANKTON AND SIOUX CITY. BUT RIGHT
NOW THAT AREA OF PARTIAL CLEARING LOOKS LIKE IT IS IN NO HURRY TO
EXPLODE INTO A MAJOR CLEARING SCENARIO. SO WITH THE INCREASE IN
CLOUDS...RAISED LOW TEMPS A COUPLE OF CATEGORIES BUT EVEN THESE LOWS
MAY BE TOO COLD. UPDATES ARE ALREADY OUT.
&&
.AVIATION.../FOR THE 18Z TAF ISSUANCE/
WITH MODEL DIFFERENCES...CONFIDENCE RATHER LOW WITH REGARD TO HOW
QUICKLY STRATUS DEPARTS THE REGION...BUT THINK CLOUDS WILL BEGIN TO
LIFT A BIT BY LATE THIS AFTERNOON. BY TONIGHT...NORTHWESTERLY WINDS
WILL BECOME RELATIVELY LIGHT. DEPENDENT ON ANY REMAINING CLOUD COVER
AND HOW LIGHT WINDS BECOME OVERNIGHT...WILL BE THE POSSIBILITY OF
FOG FORMATION OVER PORTIONS OF THE AREA VERY LATE TONIGHT INTO
FRIDAY MORNING WITH ABUNDANT NEAR SURFACE MOISTURE WITH MELTING SNOW.
&&
.PREV DISCUSSION.../ISSUED AT 257 PM CDT/
PRECIPITATION HAS ENDED ACROSS THE ENTIRE CWA LATE THIS
AFTERNOON...LEAVING BEHIND A BROAD AREA OF STRATUS OVER THE REGION.
THESE CLOUDS WILL BE THE MAIN CHALLENGE FOR THE SHORTER TERM
PERIOD...WITH MODELS NOT HANDLING THE LOW CLOUDS WELL. RUC LOOKS TO
BE THE BEST WITH THE LOW LEVEL RH FIELD...AND KEEPS THE STRATUS OVER
OUR AREA THROUGH AT LEAST THE EARLY EVENING. AS HIGH PRESSURE BUILDS
INTO THE REGION FROM THE WEST OVERNIGHT...A LESSENING SURFACE
GRADIENT WILL ALLOW WINDS TO COME DOWN BY EARLY EVENING. WENT ON THE
LOW SIDE OF GUIDANCE WITH REGARD TO LOWS TONIGHT...GENERALLY UPPER
TEENS TO LOWER 20S...WITH RELATIVELY LIGHT WINDS...SOME POSSIBLE
SNOW COVER IN SOME AREAS...AND BANKING ON CLOUDS BEGINNING TO BREAK
UP OVERNIGHT. IF CLOUDS PERSIST...IT MAY NOT GET AS COLD AS
CURRENTLY IN THE FORECAST. ANOTHER CHALLENGE WILL BE WHETHER ANY FOG
IS ABLE TO DEVELOP TOWARD FRIDAY MORNING. WHILE NOT AN IDEAL SET UP
WITH LIGHT NORTHWESTERLY WINDS...THINKING IS IF CLOUDS CLEAR OUT AND
WINDS DROP OFF...IN CONJUNCTION WITH ABUNDANT NEAR SURFACE MOISTURE
FROM RECENT RAINFALL/SNOW MELT...FOG WILL DEVELOP IN SOME AREAS. DID
NOT INCLUDE IN THE FORECAST AT THIS POINT...HOWEVER EVENING SHIFT
MAY UPDATE IF IT LOOKS MORE LIKELY.
FRIDAY LOOKS TO BE ANOTHER COOL DAY WITH THE CENTER OF THE HIGH
PRESSURE SLIDING OVERHEAD BY AFTERNOON. THERMAL PROFILES ACTUALLY
COOL A BIT OVER TODAY...THOUGH MODELS HINT AT SOME MID CLOUDS
STREAMING INTO OUR WEST...THERE WILL GENERALLY BE MORE SUN THAN
TODAY WITH HIGHS REACHING INTO UPPER 30S TO LOWER 40S. /JM
FRIDAY NIGHT WILL SEE A WEAK RIDGE OF HIGH PRESSURE MOVE ACROSS THE
AREA...LOCATED NEAR NORTHWEST IOWA BY 12Z SATURDAY. TO THE WEST
SOUTHERLY FLOW AS WELL AS CLOUD COVER WILL INCREASE AS A SHORTWAVE
MOVES INTO THE NORTHERN AND CENTRAL ROCKIES. THIS WILL MAKE FOR
TRICKY LOW TEMPERATURES FORECASTING. WILL LEAN A LITTLE MORE TOWARD
THE CONSMOS IN NORTHWEST IA WHERE WINDS WILL BE LIGHTEST AND CLOSER
TO THE CONSRAW IN CENTRAL SD WHERE WINDS AND CLOUDS WILL LIKELY KEEP
TEMPERATURES A LITTLE MILDER.
LATE SATURDAY AFTERNOON AND SATURDAY NIGHT WILL PROVE TO BE THE NEXT
CHANCE FOR PRECIPITATION. THERE ARE SOME DIFFERENCES AMONGST THE
MODELS LEADING TOWARDS LOWER CONFIDENCE IN A SOLUTION. THE GFS IS
THE MOST BOISTEROUS LEAVING COLDER AIR IN PLACE AND BRINGING HEAVIER
QPF AMOUNTS TO THE NORTHERN CWA. THE NAM IS MUCH WARMER IN THE LOWER
LEVELS THAN THE GFS WHILE THE ECMWF IS A LITTLE BIT WARMER. BOTH
MODELS WOULD LIKELY SUPPORT SNOW HOWEVER AS THE LOW LEVELS ARE
FAIRLY DRY AND WOULD EASILY SWITCH TO SNOW. SREF SOUNDINGS ALL OVER
THE PLACE DURING THIS TIME FRAME AS WELL. DYNAMICALLY THERE IS
SUPPORT FOR SOME PRECIPITATION WITH ICE PROCESSES LIKELY AS THE -12
TO -18 DEGREE C LAYER IS FROM ABOUT 9000 TO 15000 FEET AND THERE
WOULD LIKELY BE A LITTLE BIT OF FRONTAL FORCING AROUND THIS LAYER.
HOWEVER...FRONTAL FORCING WEAK AND WAVE NOT VERY WELL DEFINED SO
BELIEVE THAT THE NAM AND GFS OVERDOING QPF AMOUNTS IN THE THIRD TO
HALF AN INCH RANGE. THE MUCH STRONGER AND BETTER DEFINED SYSTEM THAT
JUST MOVED THROUGH TODAY BARELY PRODUCED AMOUNTS THIS HIGH SO WILL
LOWER BY ABOUT TWO THIRDS. WILL INCREASE POPS INTO THE LIKELY
CATEGORY SATURDAY NIGHT ALONG THE HIGHWAY 14 CORRIDOR HOWEVER AS
SOME MEASURABLE SNOWFALL LOOKS POSSIBLE. WILL KEEP HIGHS THE COOLEST
OVER THE NORTHERN CWA WHERE A MIX OF POTENTIALLY THICKER CLOUD COVER
AND COOLER LOW LEVEL THERMAL FIELD WHILE THE SOUTH COULD MIX JUST A
BIT WITH A SOUTHERLY COMPONENT. LOOKING AT LOWER 40S NORTH TO NEAR
50 SOUTH.
MOST OF THE SNOWFALL WILL BE EAST OF THE AREA ON SUNDAY MORNING WITH
GRADUALLY CLEARING SKIES THROUGH THE DAY. WINDS WILL NOT BE VERY
STRONG SO COOL HIGH TEMPERATURES IN THE MID 40S TO AROUND 50 WILL
NOT FEEL TOO BAD.
IN THE LATTER PERIODS(MON/THU)...NOT MUCH CHANGE IN THIS PERIOD AS
MODELS CONTINUE TO CONVERGE ON THE ECMWF SOLUTION. WHICH HAS BEEN
VERY CONSISTENT THIS WEEK. BASICALLY LOOKING AT A RIDGE OF HIGH
PRESSURE AT THE SURFACE VARYING FROM ABOUT THE BIG SIOUX RIVER
VALLEY EAST INTO WESTERN MINNESOTA. THIS WILL KEEP COOL CONDITIONS
IN PLACE BUT WINDS WILL LIKELY REMAIN FAIRLY CALM. THE WESTERN CWA
WILL SEE THE BEST CHANCE FOR ABOVE NORMAL TEMPERATURES WHILE
SOUTHWEST MINNESOTA WILL HAVE THE BEST CHANCE AT NORMAL TO A BIT
BELOW NORMAL TEMPERATURES. /08
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
852 PM EDT THU OCT 25 2012
.SYNOPSIS...
A STRONG RIDGE OF HIGH PRESSURE ALOFT WILL PERSIST THROUGH FRIDAY
BEFORE GIVING WAY TO A COLD FRONT WHICH WILL BRING A SLIGHT
CHANCE OF SHOWERS AND MUCH COOLER CONDITIONS TO THE REGION FOR THE
WEEKEND. MEANWHILE...HURRICANE SANDY IS CURRENTLY EXPECTED TO
MOVE NORTHWARD THROUGH THE ATLANTIC OCEAN THIS WEEKEND BEFORE
TRACKING TO NEAR THE MID ATLANTIC COAST EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 835 PM EDT THURSDAY...
ALTHOUGH 00Z SOUNDINGS REMAIN QUITE DRY ACROSS THE REGION...LOW
LEVEL SE FLOW STARTING TO GENERATE SOME LOW CLOUDS ALONG THE SRN
BLUE RIDGE/FOOTHILLS THIS EVENING WITH THIS STRATO-CU SLOWLY
PUSHING NORTH ACROSS PARTS OF NW NC. LATEST NAM ON TRACK WITH THIS
MOISTURE UNDER THE INVERSION AND SPREADS CLOUDS NORTHWARD ACROSS
SW VA BY MORNING. IN ADDITION...MORE EASTERLY FLOW DEVELOPING
ACROSS THE PIEDMONT LOOKS TO DRIVE LOW LEVEL ALTANTIC MOISTURE
WEST...WITH THIS MARINE LAYER TYPE CANOPY POSSIBLY PUSHING INTO
THE PIEDMONT AND NORTHERN AREAS LATE. GIVEN A BIT OF ADDED
UPSLOPE...BOTH THE RAP AND NAM DEVELOP FOG AND EVEN SOME DRIZZLE
OVERNIGHT OUT EAST DESPITE A VERY SHALLOW LAYER OF MOISTURE.
HOWEVER THIS LOOKS OVERDONE GIVEN CURRENT DEGREE OF DRYNESS AND
LOW DECK STILL WELL TO THE EAST/NE. THUS HAVE QUICKLY BEEFED UP
CLOUDS OVER THE SW THIS EVENING/OVERNIGHT AND ONLY INCLUDED MORE
FOG AND PERHAPS A BIT OF -DZ NEAR DAWN NE SECTIONS. ELSW EXPECT
SE WVA AND PERHAPS THE FAR SE COUNTIES TO REMAIN CLEAR WITH SKIES
BECOMING PARTLY/MOSTLY CLOUDY ELSW OVERNIGHT. BUMPED UP TEMPS A
CAT OR SO ALONG THE RIDGES...WHILE LOWERING VALLEYS AND EAST WHERE
ONSHORE FLOW SHOULD ALLOW THINGS TO COOL A LITTLE MORE AS DEWPOINTS
REMAIN RATHER LOW UNTIL FRIDAY.
PREVIOUS DISCUSSION AS OF 400 PM EDT THURSDAY...
SURFACE OBSERVATIONS AND SATELLITE IMAGERY INDICATE MAINLY CLEAR
SKIES ACROSS THE FORECAST REGION THIS AFTERNOON...AND WE CAN
EXPECT THESE CONDITIONS TO CONTINUE THROUGH THE REMAINDER OF
THURSDAY...UNDER LIGHT EASTERLY WINDS. DEFINITELY SET A NEW RECORD
HIGH TEMPERATURE TODAY FOR DANVILLE...AND AT LEAST TIED ONE FOR
BLUEFIELD. STILL MAY AT LEAST TIE A RECORD FOR BLACKSBURG WITH
ANOTHER HOUR OR TWO OF DAYTIME HEATING.
WINDS ARE EXPECTED TO BECOME MORE NORTHEASTERLY OVERNIGHT...
RESULTING IN INCREASED CLOUD COVER AS ATLANTIC MOISTURE MOVES IN
FROM THE WASHINGTON DC AREA...AND BECOMES WEDGED AGAINST THE BLUE
RIDGE BY SUNRISE TOMORROW. BELIEVE THESE LOW CLOUDS...ALONG WITH
PATCHY FOG...BUILDING ACROSS THE PIEDMONTS WILL KEEP OVERNIGHT
LOWS A LITTLE WARMER THAN LAST NIGHT...WITH MINIMUM TEMPERATURES
EXPECTED TO RANGE FROM THE MID/UPPER 40S ACROSS THE MOUNTAINS...TO
THE MID 50S FURTHER EAST.
CLOUD COVER WILL BE SLOW TO BREAK UP ON FRIDAY MORNING AND
AFTERNOON AS CIRRUS FROM HURRICANE SANDY BEGINS TO BUILD INTO THE
AREA. AS SUCH...EXPECT FRIDAY HIGH TEMPERATURES TO BE NOTICEABLY
COOLER...ALTHOUGH STILL WARM FOR THIS TIME OF YEAR...WITH AFTERNOON
HIGHS RANGING FROM THE UPPER 60S TO THE LOW 70S.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
AS OF 155 PM EDT THURSDAY...
AS SANDY PROGRESSES NORTH ALONG THE EAST COAST...ONSHORE EASTERLY
LOW LEVEL FLOW WILL INCREASE. ANTICIPATE AN INCREASE IN LOW LEVEL
CLOUD COVER AND THE ONSET OF SOME LIGHT RAIN THAT WILL INCREASE IN
COVERAGE FRIDAY NIGHT THROUGH SATURDAY. LATE IN THE DAY
SATURDAY...THE APPROACH OF A COLD FRONT WILL BRING RAIN SHOWERS TO
WESTERN PARTS OF THE AREA. AS WE CONTINUE INTO SUNDAY...SANDY WILL
BE LOCATED OFF THE COAST OF THE CAROLINAS AND THE ONSHORE FLOW
WILL TURN MORE NORTHEAST AND WE LOSE THE UPSLOPE COMPONENT SO THAT
PRECIPITATION WILL BECOME LIMITED IN THE EAST. COVERAGE OF SHOWERS
WILL INCREASE IN THE WEST AS THE COLD FRONT GETS CLOSER.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 515 PM EDT THURSDAY...
MADE UPDATES TO POPS/SKY AND WINDS TO REFLECT THE POTENTIAL TO SEE
MUCH MORE COVERAGE OF UPSLOPE PRECIP WEST INCLUDING SNOW ALONG
THE WESTERN SLOPES AND RAINFALL OVER THE NORTH UNDER THE CYCLONE
TO THE NE. ALSO WINDS COULD BE QUITE AN ISSUE BY TUESDAY WITH
GUSTS INTO ADVISORY OR WARNING LEVELS POSSIBLE ESPCLY MOUNTAINS.
WILL UPDATE THE HWO TO REFLECT THE WIND AND SNOW POTENTIAL FOR
EARLY NEXT WEEK.
AS OF 1145 AM EDT THURSDAY...
THE FOCUS ON THIS SECTION OF FORECAST CONTINUES TO BE WHAT TRACK
OF THE LOW THAT HAD BEEN NAMED SANDY TAKES...AND ITS IMPACT...OR
LACK THEREOF ON OUR WEATHER. WILL CONTINUE TO HAVE OUR FORECAST
REFLECT THAT OF HPC IN THIS TIME PERIOD. THIS SOLUTION LEANS
TOWARD THAT OF THE GFS THAT MAINTAINS THE LOW OFF THE COAST FOR A
LONGER PERIOD OF TIME BEFORE STARTING A WESTWARD TREND TOWARD NEW
ENGLAND...WITH THE MID-WEST UPPER TROUGH REMAINING A SEPARATE
ENTITY FOR A LONGER PERIOD OF TIME WITH ITS EASTERN FLANK AND
ASSOCIATED COLD FRONT OVER OUR REGION.
OUR FORECAST WILL REFLECT ONE THAT HAS ITS GREATEST FOCUS ON STRONG
NORTHWEST FLOW UPSLOPE RAIN/SNOW SHOWERS OCCURRING FROM SOUTHEAST
WEST VIRGINIA...SOUTH INTO THE NORTHERN MOUNTAINS OF NORTH CAROLINA.
AN ADDITIONAL AREA OF PRECIPITATION WILL BE ALONG AND NORTHEAST OF A
LINE FROM LEXINGTON VA TO HALIFAX VA. HERE THE WESTERN EXTENT OF
PRECIPITATION ASSOCIATED WITH THE REMNANTS OF SANDY IS EXPECTED TO
OCCUR ACROSS OUR REGION. GRANTED...AS WEATHER FORECAST MODELS
PROVIDE ADDITIONAL OUTPUT...THE PLACEMENT OF THIS AREA OF
PRECIPITATION MAY IN REALITY COVER MORE OR LESS OF THE FORECAST AREA.
REGARDLESS OF GFS OR ECMWF...THE MODELS HAVE BEEN TRENDING TOWARD
COLDER 850 MB AND SURFACE TEMPERATURES YIELDING A GREATER POTENTIAL
FOR SNOW TO BE IN THE FORECAST...ESPECIALLY FOR THE NORTHWEST FLOW
UPSLOPE ACTIVITY IN THE WEST. BOTH MONDAY NIGHT AND TUESDAY
NIGHT...UPPER 20S IN THE MOUNTAINS AND LOW TO MID 30S IN THE
PIEDMONT ARE CURRENTLY FORECAST. SO FAR...THE GROWING SEASON HAS
ENDED FOR ONLY GREENBRIER COUNTY WV AND BATH COUNTY VA. IF THESE
FORECAST LOWS ARE REALIZED...THE REMAINDER OF THE AREA SHOULD SEE AN
END TO ITS GROWING SEASON.
SURFACE WINDS MAY BE AT OR JUST A BIT BELOW WIND ADVISORY CRITERIA.
AGAIN...AS WE GET CLOSER TO THIS TIME PERIOD...WE WILL HAVE GREATER
CONFIDENCE IN SPEEDS. ALSO...WHILE NOT AT ADVISORY LEVELS...WIND
CHILLS IN THE MOUNTAINS WILL DROP INTO THE TEENS WITH 20S IN THE
PIEDMONT.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
AS OF 740 PM EDT THURSDAY...
GUIDANCE HAS BACKED OFF THE NOTION OF LOW CIGS/VIS ALONG THE BLUE
RIDGE OVERNIGHT. VERY DRY ATMOSPHERE WILL PROBABLY TAKE LONGER TO
MOISTEN UP AND THE EASTERLY COMPONENT MAY NOT BE STRONG ENOUGH OR
CONSISTENT ENOUGH CREATE A THICK ENOUGH LAYER OF SUFFICIENT RH. ALTHOUGH
THE SHIELD OF STRATUS OBSERVED LAST NIGHT MAY CREEP FURTHER SOUTH
AND WEST THAN LAST NIGHT...HARD TO FIGURE EXTENSIVE IFR CIG/VIS
WILL INVADE LYH/ROA/DAN CONSIDERING CURRENT CONDITIONS. THIS LOOKS
TO BE MORE OF A POSSIBILITY FRIDAY NIGHT. CAN`T RULE OUT SOME MVFR
VIS TONIGHT LWB/BCB. MORE SURFACE CONVERGENCE TOMORROW THANKS TO A
BETTER UPSLOPE COMPONENT MAY AD SOME MOUNTAIN CU TO THE SKIES
FRIDAY. LATE DAY HIGH CIRRUS MAY ARRIVE ACROSS LYH/DAN...FROM 15
TO 20 KFT.
EXTENDED AVIATION DISCUSSION...
THE WEATHER PICTURE FOR THIS WEEKEND AND THE EARLY PART OF NEXT
WEEK IS COMING A LITTLE INTO BETTER FOCUS AS THE WEATHER FORECAST
MODELS GRADUALLY RESOLVE THEIR DIFFERENCES CONCERNING THE TRACK
AND IMPACTS OF HURRICANE SANDY. SHOWER ACTIVITY...WITH A DECENT
POTENTIAL FOR MVFR/IFR CONDITIONS...IS EXPECTED TO PERSIST ACROSS
THE MOUNTAINS FROM SUNDAY THROUGH AT LEAST TUESDAY AS SANDY
CONTINUES TO MOVE NORTH ALONG THE COAST. AS OF THURSDAY
AFTERNOON...THE NHC PROJECTED PATH OF THE STORM CALLS FOR LANDFALL
TO OCCUR ANYWHERE FROM THE OUTER BANKS TO CAPE COD...WITH THE
LIKELIEST PATH TAKING THE STORM INTO NEW JERSEY. AS THE STORM
PASSES NORTHWARD ALONG THE COAST...EXPECT TO SEE WINDS BECOME
STRONG...POSSIBLY WITH +40KT GUSTS IN THE MOUNTAINS...FROM THE
NORTHWEST AS THE FORECAST AREA BECOMES PINCHED BETWEEN SANDY AND A
HIGH PRESSURE SYSTEM BUILDING IN FROM THE WEST. THERE ALSO IS THE
POSSIBLILITY OF GUSTY WINDS AND SNOW SHOWERS GREATLY REDUCING VIS
AND/OR CIG IN THE LWB/BLF CORRIDOR...ESPECIALLY ON TUESDAY. BECAUSE
SANDY IS SUCH A BROAD STORM...THESE GUSTY WINDS WILL LIKELY
PERSIST INTO TUESDAY BEFORE DIMINISHING. HOW STRONG THE WINDS
BECOME DEPENDS ON THE INTENSITY AND TRACK OF SANDY...WHICH REMAINS
UNCERTAIN.
&&
.FIRE WEATHER...
FIRE WEATHER CONDITIONS REMAIN A CONCERN AS WE APPROACH THE
WEEKEND. MANY PARTS OF THE CWA HAVE NOT EXPERIENCED MEANINGFUL
RAIN SINCE EARLY OCTOBER. 10-HR FUEL MOISTURES ARE DROPPING INTO
THE 8-10 PERCENT RANGE AT SEVERAL RAWS SITES DURING RECENT
AFTERNOONS. ALTHOUGH WE CURRENTLY DO NOT HAVE THE WIND OR RH
CRITERIA IN ANY STATE...CONDITIONS COULD CHANGE THIS WEEKEND AS A
TIGHT PRESSURE GRADIENT DEVELOPS BETWEEN THE HIGH PRESSURE
BUILDING SEWD FROM THE MIDWEST AND HURRICANE SANDY OFF THE EAST
COAST. SUBSIDENCE ON THE WEST SIDE OF THE HURRICANE AND
DOWNSLOPE...DRYING NW FLOW WILL COMBINE TO RESULT IN LOWERING RH
VALUES. WHAT MAY SAVE THE AREA FROM CRITICAL RH VALUES WILL BE
CLOUD COVER AND MUCH COOLER TEMPERATURES. FIRE DANGER OR RED FLAG
CRITERIA REMAINS A POSSIBILITY FOR THE WEEKEND.
&&
.CLIMATE...
RECORD HIGH TEMPERATURES WERE SET AT BLUEFIELD AND DANVILLE ON
THURSDAY.
RECORD HIGHS FOR FRIDAY...
| OCT 26TH |
BLACKSBURG VA.|75 IN 2004|
BLUEFIELD WV..|78 IN 2010|
DANVILLE VA...|81 IN 1989|
LYNCHBURG VA..|85 IN 1919|
ROANOKE VA....|86 IN 1939|
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/NF
NEAR TERM...JH/NF
SHORT TERM...DS
LONG TERM...DS/JH
AVIATION...KM/NF
FIRE WEATHER...
CLIMATE...
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1058 AM PDT Wed Oct 24 2012
.SYNOPSIS...A band of rain and mountain snow will move through the
area today and tonight. The weather will generally be quiet on
Thursday before the next weather system arrives Friday with
additional storms for the weekend. More precipitation is expected
into early next week.
&&
.DISCUSSION...
Updated the Winter Weather Advisory to increase the forecast snow
amounts a bit. Wentchee mountain sensors are reporting 4-5" at
this point. HRRR model suggests that the heaviest snow is
decreasing there right now and will end by about 2pm. Additionally
the METRo model shows road temps warming to near 40F so travel
should be much better this afternoon across Blewett Pass.
Further to the north the snow will continue into the evening but
Loup Loup road temps are road temps are already 35F and will
continue to melt any falling snow. The road temps are forecast to
fall to freezing by 7pm so we could see some re-accumulation there
if the snow is still falling by then.
Waterville cam continues to show snow, but roads are just wet so
no advisory needed there.
HRRR and NAM continue to show precip arriving in Spokane around
3pm and then ending in the evening as the band of rain/snow moves
into the northern/eastern mountains. The models actually show a
rotating spiral (i.e. vort max) in the reflectivity progs over
Wenatchee moving north to around Omak overnight but then changing
course and diving southeastward over Spokane area on Thursday for
more showers. RJ
&&
.AVIATION...
18Z TAFS: An area of rain and mountain snow will slowly move
across the area today and this evening. Expect widespread mtn
obscuration in the Cascades today and the northern/eastern
mountains this evening. METAR Ceilings in the rain will lower to
MVFR/IFR levels but should rebound to VFR after the rain ends.
However, as skies clear IFR fog and stratus will form overnight at
some of the TAF locations, mainly in the Basin and the Spokane
area. RJ
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 43 34 43 33 43 31 / 80 80 20 10 50 40
Coeur d`Alene 43 34 44 32 43 30 / 70 70 50 10 50 40
Pullman 42 32 42 30 42 30 / 70 40 40 10 60 40
Lewiston 47 36 48 35 47 36 / 70 60 30 10 60 30
Colville 44 34 47 30 46 28 / 60 90 50 10 50 40
Sandpoint 43 33 43 29 43 29 / 30 80 60 10 40 40
Kellogg 39 33 38 26 40 29 / 70 80 60 20 50 60
Moses Lake 46 31 48 34 47 31 / 40 10 10 10 40 20
Wenatchee 45 32 48 36 46 34 / 70 10 10 10 50 20
Omak 44 30 48 32 48 32 / 90 90 10 10 50 30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Winter Weather Advisory until 11 PM PDT this evening for East
Slopes Northern Cascades.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
1008 PM PDT THU OCT 25 2012
.SYNOPSIS...
WEAK HIGH PRESSURE HAS BEGUN TO MOVE OVER THE REGION. MOSTLY CLEAR
SKIES ARE EXPECTED THROUGH THE WEEKEND.TEMPERATURES WILL GRADUALLY
WARM TO A FEW DEGREES ABOVE AVERAGE BY THE WEEKEND.
&&
.UPDATE...
SOME REMNANT MID LEVEL CLOUDS SHIFTING FROM THE DIABLOS TOWARDS
THE TEMBLOR MOUNTAINS THIS EVENING DUE TO NORTHERLY OFFSHORE
WINDS. OTHERWISE CLEAR SKIES ACROSS THE DISTRICT. THE NORTH WINDS
WILL BE SHIFTING MORE NORTHEAST OVERNIGHT AS SURFACE HIGH BUILDS
AND STRENGTHENS FURTHER SOUTH OVER THE GREAT BASIN. 24 HOUR TRENDS
ARE HIGHER IN TEMPERATURES AND DEW POINTS OVER MOST OF THE
DISTRICT. THE ONE EXCEPTION IS TOWARDS THE INDIANS WELLS VALLEY.
THIS SHOULD BE A LEADING INDICATOR OF THE DRIER AIRMASS MOVING
DOWN FROM THE HIGH DESERT. MUCH OF THE INTERIOR VALLEY AREA IS
SHELTERED FROM THE STRONG NE OFFSHORE WINDS AND SHOULD SEE COOLER
LOWS WITH THE DRIER AIRMASS AND LESS WIND MIXING. THE STRONGER
OFFSHORE WINDS SHOULD REMAIN TOWARDS THE THE KERN COUNTY DESERT.
HAVE UPDATED FORECAST TO DECREASE CLOUDS IN THE SAN JOAQUIN VALLEY
AND ADJUST A FEW SPOT TEMPERATURES FOR TONIGHT ONLY. NO OTHER
CHANGES.
.DISCUSSION...
VISIBLE SATELLITE IMAGERY IS SHOWING LOW LEVEL CIRCULATION OFF THE
MONTEREY BAY COAST AND SLOWLY DRIFTING SOUTHWARD. HIGH-RES RAPID
REFRESH(HRRR) IS SHOWING DECREASING CLOUD COVER OVER THE VALLEY AS
THE LOW LEVEL CIRCULATION TRAVELS DUE SOUTH AND FURTHER OFFSHORE.
CURRENT TIMING HAS THE VALLEY CLEARING OUT JUST BEFORE SUNSET
BASED ON BOTH HRRR AND SREF SOLUTIONS. AT THIS POINT...THE BROAD
CYCLONIC CIRCULATION OVER THE WEST COAST CONTINUES TO SHIFT EAST
WITH A HIGH PRESSURE RIDGE AXIS MOVING CLOSER TO THE WEST COAST ON
FRIDAY. YET...SHORT RANGE MODELS DO NOT RELAX THE NORTHWESTERLY
FLOW ALOFT UNTIL AFTER FRIDAY AFTERNOON. THEREFORE...WITH LOCALLY
BREEZY WINDS ALOFT...FOG AND EXTREMELY COLD SURFACE TEMPERATURES
WILL NOT BE FAVORED OVER THE SAN JOAQUIN VALLEY FRIDAY MORNING.
HOWEVER...WILL KEEP A MENTION OF PATCHY FOG OVER THE SAN JOAQUIN
VALLEY FOR MORE RURAL AREAS THAT HAVE LESS OF A THRESHOLD TO FOG-
UP. IN ADDITION...TEMPERATURES WILL DROP OVERNIGHT...LOWER THEN
THURSDAY MORNING BUT NOT BY MUCH AS LOCAL WINDS WILL CONTINUE TO
BLOW FOR ONE MORE NIGHT.
AFTER FRIDAY...THE GENERAL TREND IS FOR CLEAR CONDITIONS WITH
WARMING TEMPERATURES THROUGH SUNDAY. GFS/ECMWF/UKMET/NOGAPS ALL
IN GOOD AGREEMENT WITH PLACING THE RIDGE AXIS OVER CALIFORNIA BY
SUNDAY AS THEY ALL FORM A REX BLOCKING PATTERN OVER THE NORTH-
CENTRAL PACIFIC. BY SUNDAY...GUIDANCE PLACES VALLEY MAX TEMP/S
SOME 3 TO 5 DEG-F ABOVE NORMAL BEFORE THE START OF ANOTHER COOLING
TREND. TOWARD NEXT WEEK...ALL LONGER RANGE MODELS ATTEMPT TO
BREAKDOWN THE REX BLOCK AND EJECT A TROF TOWARD THE PACIFIC
NORTHWEST/NOR- CAL BY TUESDAY NIGHT/WEDNESDAY. FEEL THAT MODELS
MAY BE PREMATURELY BREAKING DOWN THE REX BLOCK TOO SOON...WHICH
COULD LAST FOR A WEEK. DUE TO ALL MODELS DOING THIS BREAK DOWN...
CERTAINTY IS UP SLIGHTLY ON THE SOLUTION FOR EARLY NEXT WEEK. IF
THE TROF APPROACHES THE WEST COAST NEXT WEEK...IT WILL HAVE THE
DEAL WITH SANDY ALONG THE EAST COAST. EVEN WITH MODEL UNCERTAINTY
ON THE TROPICAL SYSTEM...SANDY...IT WILL EXIST OVER THE EAST COAST
EARLY NEXT WEEK. THEREFORE...THE RIDGE OVER THE MID-WEST WILL HAVE
TO AMPLIFY AS IT ADJUSTS TO THE APPROACHING TROF. MODELS DO
INDICATE THAT THE PRECIP BAND PUSHING ONTO CALIFORNIA WILL BE
FORCED TO SHIFT NORTHEAST AND POSSIBLY MISS CENTRAL CALIFORNIA.
THEREFORE...WILL ONLY MENTION A SLIGHT CHANCE OF PRECIP...STARTING
TUESDAY NIGHT...OVER THE NORTHERN THIRD OF THE DISTRICT FOR AREAS
FROM FRESNO COUNTY NORTHWARD.
&&
.AVIATION...
VFR ACROSS THE CENTRAL CA INTERIOR THRU 06Z SAT...EXCEPT PATCHY
MVFR HZ/BR IN THE SAN JOAQUIN VALLEY FROM 12Z-18Z FRI.
&&
.AIR QUALITY ISSUES...
NONE.
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM.
THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED
BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 10-25 91:1966 61:1998 62:1982 36:1971
KFAT 10-26 89:2003 57:2004 58:1927 35:1939
KFAT 10-27 89:2003 58:1896 61:1987 35:1970
KBFL 10-25 94:1917 62:1939 66:1982 35:1899
KBFL 10-26 92:2003 58:1996 61:1959 35:1939
KBFL 10-27 99:1906 56:2004 64:1987 34:1919
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...MV
AVN/FW...BINGHAM
SYNOPSIS...PJ
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS GOODLAND KS
236 AM MDT FRI OCT 26 2012
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 236 AM MDT FRI OCT 26 2012
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOW LARGE SCALE TROUGH ACROSS
THE NORTHERN PLAINS WITH A SHORTWAVE TROUGH OVER CENTRAL COLORADO.
RADAR COMPOSITE SHOWS LIGHT SNOW EXTENDING ACROSS EASTERN COLORADO
JUST ENTERING THE FAR WESTERN EXTENT OF OUR CWA. THIS HAS FORMED
ALONG AN AXIS OF H7 FRONTOGENESIS AHEAD OF H7 TROUGH AXIS. AS MEAN
H5/H7 TROUGH SHIFTS EAST LIGHT SNOW SHOULD CONTINUE TO SPREAD EAST
TOWARDS THE CO/KS STATE LINE. BEST FORCING/MID LEVEL MOISTURE SHOULD
REMAIN OVER THE WESTERN CWA. LATEST SHORT RANGE GUIDANCE GENERALLY
KEEPS LIGHT SNOW OVER OUR EASTERN COLORADO COUNTIES AND FAR WESTERN
KS THROUGH 15Z...WITH SUBSIDENCE AND ISENTROPIC DOWNGLIDE
OVERSPREADING THE CWA PUTTING AN END TO PRECIP CHANCES BY MIDDAY.
WE WILL CONTINUE TO SEE BELOW NORMAL TEMPERATURES TODAY AND TONIGHT
WITH THE SAME COLD AIR MASS STILL IN PLACE. HIGHS TODAY WILL BE
SIMILAR TO FRIDAY WITH AFTERNOON TEMPS IN THE UPPER 30S ACROSS THE
WEST AND MID 40S ACROSS THE EAST. CLOUD COVER COULD LIMIT
RADIATIONAL COOLING TONIGHT...HOWEVER WITH THE COLD AIR MASS STILL
IN PLACE LOWS SHOULD STILL DROP TO THE MID TO UPPER 20S FOR MOST
LOCATIONS...AND NEAR 20F WHERE CLOUDS CLEAR OUT.
NW FLOW DEVELOPS OVER THE CWA FRIDAY AS H5 RIDGE BUILDS OVER THE
WESTERN US AND BEGINS TO SHIFT TOWARDS THE CENTRAL ROCKIES THROUGH
THE WEEKEND. GFS HAS INDICATED A WEAK SHORTWAVE TROUGH WILL MOVE
JUST NORTH OF THE CWA IN NEBRASKA SATURDAY. MOST GUIDANCE
GENERALLY INDICATES STORM TRACK SHOULD REMAIN NORTH OF OUR
CWA...SO I KEPT DRY FORECAST IN PLACE. AIR MASS OVER THE CWA
SHOULD SLOWLY MODERATE WITH HIGHS IN THE LOW 50S SATURDAY...AND
UPPER 50S ON SUNDAY.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 236 AM MDT FRI OCT 26 2012
DRY CONDITIONS WILL CONTINUE THROUGH MOST OF NEXT WEEK AS THE UPPER
LEVEL RIDGE REMAINS OVER THE WESTERN HALF OF THE CONUS. MID WEEK AN
UPPER LEVEL TROUGH MOVES ONSHORE OVER THE PACIFIC NORTHWEST...MOVING
INTO THE CENTRAL PLAINS BY THE START OF THE WEEKEND. THE GEFS
MEMBERS DISAGREE WITH THE TRACK OF THE TROUGH...WITH MOST MEMBERS
KEEPING IT NORTH OF THE AREA. TEMPERATURES THROUGH THURSDAY WILL BE
NORMAL...WITH BELOW NORMAL TEMPERATURES IN STORE AS A COLD FRONT
MOVES THROUGH FRIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1108 PM MDT THU OCT 25 2012
VFR CONDITIONS WILL PREVAIL AT MCK AND GLD WITH A BRIEF PERIOD OF
MVFR CONDITIONS POSSIBLE BETWEEN 10-14Z AT GLD DUE TO LOWER
CEILINGS AND A LITTLE LIGHT SNOW MOVING INTO THE AREA FROM THE
WEST AS A WEAK TROUGH MOVES ACROSS THE REGION. WINDS WILL BE LIGHT
AND VARIABLE THROUGH THE PERIOD...BECOMING MORE SOUTHERLY BY LATE
IN THE AFTERNOON AND EVENING ON FRIDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JTL
AVIATION...LOCKHART
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
326 AM EDT FRI OCT 26 2012
.Short Term (Today through Saturday)...
Issued at 326 AM EDT Fri Oct 26 2012
...Sharp cold front moving through the region today will result in
falling temperatures...
Well advertised potent upper level trough and associated surface
cold front are heading through the region early this morning. The
models have been playing catch up with respect to the timing and the
latest HRRR and RAP guidance seems to have a good handle on things.
Based on WSR-88D velocity moments, the front is just west of a
KSDF-KFTK-KBWG line. The front should cross the I-65 corridor
within the next hour and then head toward the I-75 corridor towards
sunrise. A brief period of breezy, perhaps gusty winds will
accompany the front as it pushes through with winds shifting from
the south to the northwest. Precipitation is lagging behind the
front by a few hours, so in the near term, dry conditions are
expected. Based on upstream observations, we`re seeing a 12-15
degree drop behind the front, so while temperatures in the central
sections are still in the mid-upper 60s, those reading will fall
quickly over the next couple of hours.
For today, the frontal boundary is forecast to push eastward through
the day. Some pre-frontal warming may occur in the east just ahead
of the front, but temperatures by and large will fall throughout the
day. All of the deterministic and ensemble guidance continues to
show that post-frontal precipitation is very likely, so we have
bumped up the clouds and precipitation chances a bit for today.
Highest PoPs today will be in the west and central sections with
higher PoPs in the east holding off until later this afternoon and
evening. As for temperatures, highs today will range from the upper
40s to the lower 50s in the west and central sections. Upper 50s to
the lower 60s are likely in the east, but these will occur early as
temperatures fall into the upper 40s to lower 50s by evening.
For tonight, the aforementioned frontal boundary will continue to
surge eastward. Lagging post-frontal precipitation band will likely
continue to slowly move eastward through the forecast area. It
appears that a weak upper level wave will pass overhead tonight,
which may enhance our PoP chances for the evening and early
overnight hours. Will keep chance PoPs in for the far
west/northwest sections with likely PoPs in the central and eastern
sections. Overall, best chances of rain tonight look to be over our
eastern forecast area. Precipitation should generally be exiting
the forecast area by dawn and drier air will attempt to punch into
our west/northwest sections late. With this drier air coming in,
we`re likely to see some partial clearing toward sunrise which will
allow for a gradient of temperatures across the area. Overnight
lows should range from the upper 30s in the far west/northwest with
lower 40s in the central and lower-mid 40s in the east.
For Saturday, high pressure to the west will continue to slowly
build into the region. This will result in clearing working across
the forecast area from west to east. Typically the models are too
fast at clearing things out. In addition, cold air advection aloft
will likely result in a stratocumulus deck building in. Partly
cloudy conditions look reasonable for areas west of I-65 with mostly
cloudy conditions east of I-65...though skies will likely become
mostly clear by evening. As for temperatures, highs will be in the
upper 40s to around 50 in the east/northeast with lower-middle 50s
across the central and western sections.
.Long Term (Saturday Night through Thursday)
Issued at 305 AM EDT Fri Oct 26 2012
Across the country, the big weather story early next week will
concern the mid-Atlantic and our northeastern states. Hurricane
Sandy, now a category one hurricane east of Florida is increasingly
likely to begin developing into into an intense extra-tropical
cyclone by Sunday well east of North Carolina. The majority of the
most recent guidance shows a deep 500mb trough forming over the
Appalachians. Should this occur, this cyclone would be pulled
northwest towards New York or southern New England by late Monday
with an exceptionally deep surface low and gale force winds.
The unusual track of this storm is a result of strong blocking
across the entire Atlantic basin. Upstream from this, across the
Lower Ohio Valley and midwest, northerly flow already in place
Sunday will simply not budge, continuing through at least Thursday.
A lengthy period of cool weather is practically certain for the
Commonwealth and southern Indiana. Clearing is forecast to have
taken place across southern Illinois and western Kentucky by late
Saturday. However, cloud cover is likely to linger across eastern
Kentucky into Sunday morning. Across central Kentucky, cloud cover
will remain a tricky forecast through Sunday as the NAM and the GFS
have contrasting forecasts on how quickly clouds erode over eastern
Kentucky.
At the surface, a ridge of high pressure extending southward along
the Mississippi River on Sunday simply will not budge. Northerly
surface winds are likely for our region for all of the early portion
of next week as the afore-mentioned deep nor`easter creeps slowly
over southern New England.
Temperatures will remain pretty consistent Sunday through Wednesday
in this basically blocky weather pattern. Expect highs in the lower
to mid 50 each day, with Monday potentially a bit cooler. Lows will
bottom out in the lower to mid-30s.
Expect clear to partly cloudy skies Monday through Thursday. It is
possible that overcast skies associated with the western edge of the
New England storm may push as far west as central Kentucky late
Monday or Tuesday if some of more western model solutions verify.
&&
.Aviation (06Z TAF Issuance)...
Issued at 1258 AM EDT Fri Oct 26 2012
VFR conditions will continue for the next couple of hours as a cold
front approaches from the northwest early this morning. Utilizing
upstream WSR-88D velocity patterns, the wind shift line is very
evident in the base velocity moments. Utilizing our distance/speed
tool, this front looks to push through KSDF around 0715-0745Z,
through KBWG around 0815-0845Z, and through KLEX around 0915-0945Z.
Upstream observations also show a period of gusty winds just behind
the front. So will be carrying sustained winds of 12-15kts with
gusts up to 20-24kts for an hour or two behind the front. Winds out
ahead of the front will be out of the south and southeast, but
quickly shift to the northwest after the front pushes through the
terminals.
Ceilings are expected to gradually lower behind the front with
ceiling likely settling near 2000ft AGL by 26/12Z. Post frontal
rain band is lagging behind, so am not expecting precipitation into
KSDF and KBWG until 26/13-14Z and even then that looks to be pretty
scattered so the VCSH wording from the previous forecast will be
used. Better chances of precipitation will likely hold off until
26/17-18Z where MVFR vsbys/cigs will likely prevail through the
remainder of the afternoon.
VFR conditions tonight will end Friday behind a cold front forecast
to get through the KBWG and KSDF terminals around daybreak and KLEX
later in the morning. Expect at least MVFR clouds behind this front,
with showers starting a few hours later. These showers will persist
through the rest of the TAF period as the front slows down over the
Appalachians. Expect a west southwesterly shift in the winds just
ahead of the front before more steady north northwesterly winds kick
in.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Short Term.......MJ
Long Term........JSD
Aviation.........MJ
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
125 AM EDT FRI OCT 26 2012
.Forecast Update...
Updated at 125 AM EDT Fri Oct 26 2012
Did a quick update to better time the frontal passage through the
forecast area later this morning. Currently the cold front is
pushing into our northwest CWA. It should pass through the I-65
corridor by 26/0730-0800Z and then east of the I-75 corridor by
26/12Z. A brief period of breezy conditions is expected in the wake
of the frontal passage where winds may gust up to 25-28 MPH.
Expanding area of showers out across Missouri/southern Illinois, and
western KY will also shift eastward later this morning. For now,
have gone closer to the 26/02Z HRRR model run which has a good
handle on temps and wind shifts/speeds for the next few hours. Some
scattered shower activity will likely develop over the northwest CWA
toward dawn. We`ll address those details in the next
discussion/update around 330 AM EDT.
&&
.Short Term (Tonight through Friday Night)...
Issued at 310 PM EDT Thu Oct 25 2012
...Sharp cold front will bring falling temperatures Friday...
A potent upper-level trough and associated surface cold front will
arrive Friday morning. Models have sped up the cold front a bit,
which is currently plowing through Illinois and Missouri at this
time. It appears to cross the Ohio River in the Louisville area just
before daybreak Friday. It will continue to move southeast across
central Kentucky through the day. The system will be dominated by
post-frontal precipitation, so not expecting much of any convection
ahead of the front Friday. With models speeding up the front, any
daytime heating and frontal interaction would occur along or just
south and east of the forecast area border in east- and
south-central Kentucky. So, will drop thunder wording from the
forecast.
Otherwise, post-frontal showers will begin to overspread our
northwest forecast area Friday morning, slowly shift southeast
through the afternoon, and continue a slow east-southeast
progression overnight (dissipating some along the way). We should
start to see precip ending across the northwest Friday night.
Area-wide rainfall totals will range from 0.25-0.7 inches, with the
higher amounts being positioned along the Ohio River.
Lows tonight will be rather mild, with temperatures ranging from
generally the mid to upper 50s. The high temperature forecast for
Friday continues to be challenging with the front having sped up.
Given this, temperatures will not rise much, if any for some
locations, during the morning hours. Southwestern Indiana will
likely see steady or slowly falling temperatures toward 50 degrees
by mid-afternoon Friday. Only the Bluegrass and Lake Cumberland
Regions will see rebounding temperatures during the morning hours,
with highs possibly reaching the lower 70s before falling by late
afternoon. Winds will quickly shift from southwest to northwest and
increase into the 10-15 mph range with the frontal passage.
Temperatures will continue to fall through Friday night. Overnight
lows will range from the upper 30s in southwestern Indiana to mid
40s in east-central Kentucky. North winds will remain in the 10-15
mph range overnight.
.Long Term (Saturday through Thursday)
Issued at 305 PM EDT Thu Oct 25 2012
An extended period of unseasonably cool temperatures is in store as
a chunk of the polar vortex breaks off and parks itself over the
eastern CONUS.
Saturday will begin with plenty of cloud cover, and lingering rain
chances roughly east of I-65. Expect the rain to exit by early
afternoon, and at least partial clearing in most places by the end
of the day. Temps will be a bit tricky, especially in the east, due
to the dependence on how much sunshine we get. Look for highs in the
lower 50s over the Bluegrass, with upper 50s west of I-65 in
Kentucky.
Nighttime temps are a bit tricky due to the pressure gradient that
will persist over the Ohio Valley as Hurricane Sandy becomes
extratropical and gets absorbed into the deep mid-latitude upper
trough. North winds will stay up at 5-10 mph on Saturday night, so
even if a few locations dip into the mid 30s, frost will be hard to
come by. Could be a bit colder Sunday night and Monday night, and
the grids will show patchy frost, but nothing worthy of HWO mention
just yet.
By Tuesday and Wednesday there should be a fairly broad cyclonic
circulation, with N-NW winds coming off the Great Lakes. Expect at
least lake-effect clouds, but it is too soon to say if there will be
enough moisture available for precip. Both model agreement and
run-to-run consistency are lacking at this point, so will not
forecast precip.
Deep upper trough remains fairly well entrenched along the East
Coast through at least Thursday, with surface high pressure ridging
down the Mississippi Valley. Will maintain chilly northerly flow
over the Ohio Valley, with low temperatures near freezing and highs
struggling to crack 50, some 10-15 degrees below normal both day and
night.
&&
.Aviation (06Z TAF Issuance)...
Issued at 1258 AM EDT Fri Oct 26 2012
VFR conditions will continue for the next couple of hours as a cold
front approaches from the northwest early this morning. Utilizing
upstream WSR-88D velocity patterns, the wind shift line is very
evident in the base velocity moments. Utilizing our distance/speed
tool, this front looks to push through KSDF around 0715-0745Z,
through KBWG around 0815-0845Z, and through KLEX around 0915-0945Z.
Upstream observations also show a period of gusty winds just behind
the front. So will be carrying sustained winds of 12-15kts with
gusts up to 20-24kts for an hour or two behind the front. Winds out
ahead of the front will be out of the south and southeast, but
quickly shift to the northwest after the front pushes through the
terminals.
Ceilings are expected to gradually lower behind the front with
ceiling likely settling near 2000ft AGL by 26/12Z. Post frontal
rain band is lagging behind, so am not expecting precipitation into
KSDF and KBWG until 26/13-14Z and even then that looks to be pretty
scattered so the VCSH wording from the previous forecast will be
used. Better chances of precipitation will likely hold off until
26/17-18Z where MVFR vsbys/cigs will likely prevail through the
remainder of the afternoon.
VFR conditions tonight will end Friday behind a cold front forecast
to get through the KBWG and KSDF terminals around daybreak and KLEX
later in the morning. Expect at least MVFR clouds behind this front,
with showers starting a few hours later. These showers will persist
through the rest of the TAF period as the front slows down over the
Appalachians. Expect a west southwesterly shift in the winds just
ahead of the front before more steady north northwesterly winds kick
in.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........MJ
Short Term.......MJP
Long Term........RAS
Aviation.........MJ
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
243 AM CDT FRI OCT 26 2012
.DISCUSSION...
MAIN SHORT TERM CONCERN DEALS WITH CLD CVR TODAY WHICH WILL
CORRELATE TO SOME TEMPERATURE VARIATIONS IF MORE OR LESS STRATO-CU
DEVELOPS. OVER THE PAST TWO HRS...A LARGE CLEARING LINE HAS
DEVELOPED ACROSS CENTRAL AND SOUTHERN MN...ONLY THE FAR NW AND SW
HAD MOSTLY CLOUDY SKIES. LATEST RAP DOES HAVE THIS TYPE OF
SCENARIO OF CLEARING OUT FOR MOST OF THE FA DURING THE EARLY
MORNING HRS...BUT QUICKLY SATURATES UP TO ARND 90H BY 9 AM TO
NOON. WITH A LARGE AREA OF CLDS UPSTREAM...AND THE MEAN FLOW
CONTINUES FROM THE W/NW...WILL LEAD TOWARD CLOUDING UP AGAIN BY
NOON WITH TEMPERATURES CLOSE TO PREVIOUS FORECAST. SOME OF THE RAP
SOUNDINGS INDICATED VERY STEEP LAPSE RATES FROM THE SFC... UP TO
80H WITH CAPES 50 TO 100 J/KG. THE DEPTH OF THE MOISTURE AND
ASSOCIATED HIGHER CAPES OCCUR ACROSS MAINLY THE NE FA. ALTHOUGH
THE CRITICAL TEMPS THAT ARE ASSOCIATED WITH THE DEVELOPMENT OF ICE
CRYSTALS ARE LIMITED FOR MOST OF THE FA...SOME INDICATIONS THAT
THE DEPTH OF THE MOISTURE IN THE N/NE FA COULD ALLOW FOR SOME
-SNSH.
THE WEAK SYSTEM EXPECTED OVER THE WEEKEND HAS WEAKENED EVEN FURTHER
FOR THIS FORECAST PERIOD WHICH MEANS THAT THE CHC OF MEASURABLE
PRECIPITATION WILL BE VERY UNLIKELY. THE MAIN FACTOR IS THE VERY
DRY AIR MASS IN PLACE WHICH WILL TAKE TIME TO SATURATE THE THERMAL
COLUMN THIS WEEKEND. BEST CHC OF MEASURABLE PRECIPITATION WILL
OCCUR IN FAR SW/WC MN WHERE SLIGHTLY BETTER 85-70H DYNAMICS
EXISTS.
PAST THIS WEEKEND...THE OVERALL PATTERN WILL BE HIGHLY DEPENDENT
ON THE EVOLUTION OF HURRICANE SANDY AND HOW IT WILL TRANSLATE
ACROSS THE EASTERN U.S. CURRENT MODELS HAVE THIS SYSTEM MERGING
WITH A SECONDARY STORM SYSTEM MOVING SE ACROSS THE GREAT
LAKES/OHIO VALLEY OVER THE WEEKEND. CURRENT TRENDS HAVE THE
HURRICANE OR REMNANTS OF THIS TROPICAL SYSTEM...MOVING ONSHORE
NEAR THE NEW JERSEY/DELAWARE STATE LINE. AS THESE SYSTEMS
COMBINE...A VERY LARGE STORM IS EXPECTED TO SLOWLY MOVE FROM THE
MID ATLANTIC REGION...N/NW TO THE EASTERN GREAT LAKES. THIS WOULD
LEAD TO THE CONTINUED N/NW FLOW ACROSS THE UPPER MIDWEST.
BASICALLY THIS IS A DRY AND COOL PATTERN FOR OUR REGION. ..JLT..
&&
.AVIATION.../06Z TAF ISSUANCE/
WIDESPREAD STRATUS ACROSS MN AND WI TONIGHT IS SHOWING LITTLE SIGN
OF DISSIPATING SOON. WE HAVE BEEN TOO AGGRESSIVE IN CLEARING THESE
CLOUDS THIS EVENING...SO TOOK A MORE PESSIMISTIC APPROACH AND KEPT AT
LEAST BKN 4000-5000 THROUGH LATE THIS MORNING. THERE ARE A FEW
BREAKS OUT THERE...BUT THESE ARE MAINLY SOUTH OF THE TAF SITES.
WINDS WILL REMAIN BREEZY OUT OF THE W-NW THROUGH THE DAY.
KMSP...
VFR CONDITIONS EXPECTED FOR THE NEXT 30 HOURS. TIMING THE
CLEARING OF STRATUS IS STILL MAIN CONCERN FOR THIS TAF
ISSUANCE. KEPT THE CLOUDS THROUGH THE MORNING..VFR CEILINGS
THOUGH.
/OUTLOOK FOR KMSP/
SAT...VFR. WINDS LGT AND VRBL.
SUN...MVFR POSSIBLE. SLIM CHANCE OF IFR. CHC -SN IN THE MORNING. WINDS
SE AT 5 KTS.
MON...VFR. WINDS SE AT 5 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
JLT/CLF
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1152 PM CDT Thu Oct 25 2012
...UPDATED AVIATION DISCUSSION...
.UPDATE...
/756 PM CDT Thu Oct 25 2012/
Low cloud deck has become quite extensive upstream and stretches from
western MO all the way into Canada. With trajectories taking this
cloud cover straight into the forecast area, it is hard to see these
clouds clearing out any time soon. RAP has been the only model to
resolve this cloud cover and it keeps the entire area cloudy all
night long. It also maintains some weak gusts through the night with
clouds and ongoing CAA keeping us somewhat mixed. Given the ongoing
CAA and BL moisture that is obviously thicker than other models
think (per 00Z OAX/ABR/UNR soundings), the RAP is likely correct in
keeping us cloudy and breezy through the night and probably well into
tomorrow morning as well. Therefore made significant changes to
clouds and winds overnight. These cloudy and breezy conditions will
also keep temperatures from getting as cold as previously forecast,
though extent of CAA should still let them drop into the lower and
middle 30s which are already on the doorstep.
Hawblitzel
.DISCUSSION...
Tonight through Saturday...
As precipitation exits the forecast area this afternoon, the main
focus for the short term will be temperatures, particularly tonight
and Friday night lows. Models don`t seem to have a good handle on
the widespread stratus building southward across portions of eastern
Nebraska and Iowa, which has the potential to strongly impact the
low temperature forecast tonight. Current water vapor imagery shows
some signs of developing subsidence behind the departing upper-level
jet streak in the eastern Dakotas; however, it is yet to be seen
whether this will translate to erosion of the low-level cloud field
this evening. Both the NAM and RAP do dry out first the midlevels
and eventually the low levels by 06z across southeast Nebraska and
into the forecast area, so have still continued a decreasing trend
in cloudiness tonight, leading to a cooler low temperature forecast
across the area. However, with some near-surface moisture remaining
and a more rapid temperature fall after 06z, do not think that a
freeze will be likely across the region even if clouds clear out
completely.
The setup on Friday night looks much more prototypical for a hard
freeze, with a 1032 mb surface high filtering into the central
Plains, pushing the surface ridge axis over northwest Missouri
shortly after midnight. Temperatures could easily drop into the mid
to upper 20`s across the majority of the region Saturday morning,
and would likely remain below freezing for several hours. If the
forecast remains on track, a freeze warning will be needed for areas
that have not already experienced a hard freeze this fall. The ridge
axis will remain over the region through early afternoon on
Saturday, keeping daytime temperatures 10 to 15 degrees below normal
in the upper 40s to lower 50s.
Laflin
Medium Range (Sunday through Thursday):
High forecast confidence this period as upper level flow remains
stagnant in the wake of a large downstream block formed by the
merging of an eastern trough and Hurricane Sandy into a potential
superstorm. This will maintain a steady northwest upper flow regime
over the regime which further amplify late in the period as
additional troughing builds into the Pacific Northwest.
All in all, precipitation chances are near zero through the period
and the effects of negative thermal advection vs. insolation will
generally offset each other. This will keep temperatures steady
through much of the week with highs in the low-mid 50s and lows in
the low-mid 30s.
Bookbinder
&&
.AVIATION...
For the 06Z TAFs...MVFR deck remains widespread across the MO
Valley/Plains though there are some breaks showing up upstream across
NE/IA. Cigs across that area seem to be lifting slightly into VFR.
Timed this break into KC area around 09Z, at which point cigs may
scatter and/or lift into VFR at times. Clouds should gradually
scatter out through the day and remain VFR after mid morning.
06
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1128 PM CDT THU OCT 25 2012
.UPDATE...
ISSUED AT 851 PM CDT THU OCT 25 2012
COLD FRONT HAS PUSHED SE OF OUR FORECAST AREA EARLY THIS EVNG.
POST FRONTAL BAND OF SHOWERS AND A FEW THUNDERSTORMS HAS
TRANSLATED EWD INTO SERN MO AND SWRN IL...MAINLY FROM STL S AND
E. THIS BAND OF PRECIPITATION WAS IN A REGION OF 850 MB MOISTURE
CONVERGENCE ALONG THE 850 MB FRONT...AND APPEARED TO BE SHIFTING
EWD A LITTLE FASTER THAN THE MODELS HAD FORECAST WHICH WILL LIKELY
LEAD TO A QUICKER ENDING OF THE RAIN TGT. SLOWED THE CLEARING OF
THE CLOUD COVER LATE TGT AND SAT WITH PLENTY OF LOW LEVEL
CLOUDINESS ACROSS ERN NEBRASKA AND IA WHICH WILL ADVECT SEWD
THROUGH OUR AREA. THERE MAY BE SOME BREAKS OR HOLES IN THE
OVERCAST BUT THESE SHOULD BE SHORT LIVED. THE RUC OR RAP MODEL
SEEMS TO HAVE THE BEST HANDLE ON THE CLOUD FORECAST. WITH CLOUDY
SKIES CONTINUING THROUGH THE NIGHT ALONG WITH STRONG AND GUSTY
NWLY SFC WINDS THE LOW TEMPERATURES MAY NOT BE QUITE AS COLD AS
PREVIOUSLY THOUGHT...ALTHOUGH STILL WELL BELOW NORMAL DUE TO THE
STRONG CAA TGT.
GKS
&&
.SHORT TERM...
ISSUED AT 239 PM CDT THU OCT 25 2012
(TONIGHT)
A STRONG COLD FRONT WILL CONTINUE MOVING SEWD THROUGH THE CWA
TONIGHT WITH POSTFRONTAL SHRA SPREADING ACROSS THE AREA. PCPN
COVERAGE SHOULD DIMINISH OVER MOST OF THE AREA AFTER 06Z BASED ON
MODEL FCSTS OF FRONTOGENETICAL FORCING FROM THE SFC THROUGH 700MB.
AN ISOLATED THUNDERSTORM ALONG THE SLOPED FRONTAL SFC IS POSSIBLE
THIS AFTN BUT OVERALL INSTABILITY PROFILES SUGGEST ONLY LIMITED
TSRA POTENTIAL. THE STRONG WIND GUSTS ONGOING AT AFD ISSUANCE
SHOULD SUBSIDE AFTER SUNSET HOWEVER SUSTAINED WINDS ARE EXPECTED
TO REMAIN BETWEEN 10-15 KTS FOR MOST OF THE NIGHT DUE TO THE TIGHT
SFC PRESSURE GRADIENT. TEMPERATURES WILL CONTINUE FALLING THROUGH
THE NIGHT DUE TO STRONG CAA AT LOW LEVELS WITH OVERNIGHT LOWS IN
THE 30S AND 40S...AN IMPRESSIVE SWING FROM THE WIDESPREAD 70S AND
80S NOTED THIS AFTN.
KANOFSKY
&&
.LONG TERM...
ISSUED AT 323 PM CDT THU OCT 25 2012
(FRIDAY THROUGH SATURDAY)
MODEL GUIDANCE HAS TRENDED JUST A BIT FASTER WITH TIMING OF
FROPA/ASSOCIATED WEATHER IMPACTS AFFECTING FAR SE CWA TOMORROW
MORNING. CURRENTLY HAVE SKIES SCATTERING/CLEARING OUT QUICKLY EARLY
TOMORROW WHICH IS SUPPORTED BY MODEL RH PLOTS. HOWEVER...AM A BIT
CONCERNED LOOKING UPSTREAM IN CENTRAL PLAINS WHICH IS CURRENTLY
EXPERIENCING BKN-OVC MVFR CEILINGS. IF LOW CLOUDS HANG ON A BIT
LATER THAN ANTICIPATED...HIGH TEMPERATURES MAY BE A BIT COOLER.
REGARDLESS...EXPECT HIGHS NEARLY 30 DEGREES COOLER TOMORROW IN SOME
AREAS AS STRONG CAA REIGNS THROUGH THE DAY WITH THE 0C 850-HPA
ISOTHERM ADVANCING TO THE CENTRAL PORTION OF THE CWA BY 0000 UTC
SATURDAY.
MAIN CONCERN FOR THE SHORT-TERM PERIOD WILL BE LOW TEMPERATURES ON
FRIDAY NIGHT/EARLY SATURDAY MORNING. WITH CLEAR SKIES...SFC RIDGE
AXIS DRAPED FROM C MO TO NE MO...LIGHT WINDS...AND L/M 20S DEWPOINTS
ADVECTING IN FROM THE NW...EXCELLENT RADIATIONAL COOLING
CONDITIONS SHOULD BE PREVALENT. WITH LOW TEMPERATURES RANGING FROM
27-32...WILL BE ISSUING A FREEZE WATCH THOSE COUNTIES ALONG AND
WEST OF MISSISSIPPI RIVER. THE WATCH VERY WELL MAY NEED TO BE
UPGRADED TO A WARNING IF FORECAST CONFIDENCE INCREASES WITH TIME.
(SUNDAY THROUGH THURSDAY)
DRY WEATHER WITH BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE
REST OF THE PERIOD. NIGHTTIME LOWS WILL BE QUITE CHILLY...WITH THE
COLDEST NIGHT EXPECTED TO BE MONDAY MORNING WHICH MAY BRING ANOTHER
WIDESPREAD FREEZE TO MOST OF THE AREA. A BIT MORE UNCERTAINTY WITH
REGARDS TO SUBFREEZING TEMPERATURES ON SATURDAY NIGHT/SUNDAY MORNING
DUE TO EXPECTED CLOUD COVER. SFC WINDS WILL REMAIN LIGHT/NORTHERLY
THROUGH THE EXTENDED AS SFC RIDGE AXIS REMAINS QUASI-STATIONARY. AT
MID/UPPER LEVELS OF THE ATMOSPHERE...INITIALLY NW FLOW WILL VEER TO
A MORE NORTHERLY COMPONENT AS HURRICANE SANDY PHASES WITH A NORTHERN
STREAM SHORTWAVE TROUGH SOMETIME LATE MONDAY/EARLY TUESDAY OVER THE
EASTERN SEABOARD. THIS LARGE AND POWERFUL SYSTEM WILL ACT TO BLOCK
UPSTREAM FLOW...KEEPING THE LSX CWA COOL AND DRY THROUGH NEXT
THURSDAY.
GOSSELIN
&&
.AVIATION...
ISSUED AT 1125 PM CDT THU OCT 25 2012
POST FRONTAL RAIN HAS MOVED SOUTHEAST OF THE TERMINALS. MVFR
CEILINGS AND GUSTY NORTHWEST WINDS TO CONTINUE OVERNIGHT. CEILING
WILL RISE TO VFR FRIDAY MORNING...SCT AND EVENTUALLY CLEAR BY
FRIDAY EVENING. WIND SHOULD DECREASE BY FRIDAY EVENING AS HIGH
PRESSURE BUILDS INTO THE REGION.
SPECIFICS FOR KSTL...
MVFR CEILING WILL LIFT TO VFR BY FRIDAY MORNING WITH CLEARING
TREND DURING THE AFTERNOON. GUSTY NORTHWEST WIND WILL DECREASE ON
FRIDAY AS HIGH PRESSURE BUILDS INTO THE AREA.
CVKING
&&
.PRELIMINARY POINT TEMPS/POPS...
ST LOUIS 40 54 34 54 / 50 10 5 0
QUINCY 34 51 29 50 / 10 5 0 0
COLUMBIA 34 52 29 52 / 10 5 0 0
JEFFERSON CITY 35 53 30 53 / 10 5 0 0
SALEM 42 53 34 54 / 80 30 5 0
FARMINGTON 40 53 32 53 / 70 20 5 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...FREEZE WATCH FROM LATE FRIDAY NIGHT THROUGH SATURDAY MORNING FOR
AUDRAIN MO-BOONE MO-CALLAWAY MO-COLE MO-CRAWFORD MO-
FRANKLIN MO-GASCONADE MO-IRON MO-JEFFERSON MO-KNOX MO-LEWIS
MO-LINCOLN MO-MADISON MO-MARION MO-MONITEAU MO-MONROE MO-
MONTGOMERY MO-OSAGE MO-PIKE MO-RALLS MO-REYNOLDS MO-SHELBY
MO-ST. CHARLES MO-ST. FRANCOIS MO-ST. LOUIS CITY MO-ST.
LOUIS MO-STE. GENEVIEVE MO-WARREN MO-WASHINGTON MO.
IL...FREEZE WATCH FROM LATE FRIDAY NIGHT THROUGH SATURDAY MORNING FOR
ADAMS IL-BROWN IL-CALHOUN IL-GREENE IL-JERSEY IL-MACOUPIN
IL-MADISON IL-MONROE IL-PIKE IL-ST. CLAIR IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
333 AM CDT FRI OCT 26 2012
.SHORT TERM...TODAY THROUGH SUNDAY NIGHT. A COOLER PATTERN WILL BE
IN PLACE ACROSS THE CENTRAL PLAINS INTO THE WEEKEND UNDER THE
INFLUENCE OF AN UPPER TROUGH FM MANITOBA/ONTARIO ACROSS THE
NORTHERN/CENTRAL PLAINS. A 1033MB SURFACE HIGH WILL BUILD
SOUTHEAST FM MT/WY INTO NEBRASKA TODAY WITH LITTLE CHANGE IN THE
COLDER AIRMASS IN PLACE ACROSS OUR AREA. STRATUS CLOUDS HAVE
EXPANDED ACROSS CENTRAL NEBRASKA/NORTHERN KANSAS DURING THE PRE
DAWN HOURS...AND THIS CLOUD COVER HAS NOT BEEN HANDLED WELL BY MODELS.
PER SATELLITE IMAGERY...SOME CLEARING HAS COMMENCED ACROSS EASTERN
NEBRASKA INTO FAR NORTHEAST KANSAS AND HRRR PROGS SUGGEST THE
CLEARING MAY REACH OUR EAST/NORTHEAST COUNTIES...WHILE THE LOWER
CLOUDS MIGRATE TO THE SOUTHWEST. HAVE TO ADMIT CONFIDENCE IS NOT
HIGH ON EXTENT OF CLOUD COVER TODAY WHICH WILL ULTIMATELY HAVE AN
IMPACT ON OUR HIGH TEMPERATURES. BELIEVE ITS BEST TO KEEP THINGS
CONSERVATIVE AND WILL PLACE MAX TEMPS AROUND 40F IN NEB/LOW 40S IN NC
KANSAS. THE CLOUDS LOOK TO SCATTER TONIGHT...BEFORE INCREASING
AGAIN ON SATURDAY AHEAD OF NEXT APPROACHING WAVE. IN DECREASING
CLOUDS...DRIER/COLD AIRMASS WE ARE LOOKING AT ANOTHER COLD NIGHT
WITH LOW TEMPS WELL BELOW FREEZING.
SATURDAY THE FORECAST TURNS A LITTLE MORE INTERESTING AS 125KT H3
JET PROGRESSES SOUTHEAST IN NORTHWEST FLOW/ON BACK SIDE OF TROUGH
WITH DIVERGENCE ALOFT INCREASING IN OUR NORTHERN CWA IN LFQ OF JET.
A DECENT H7 SHORTWAVE TROUGH CROSSES NORTHERN/CENTRAL NEBRASKA IN
THE AFTN. WAA INCREASES AHEAD OF APPROACHING WAVE WITH ISENTROPIC
LIFT NOTED IN AFTN ON THE 290K SFC ACROSS OUR NORTHERN ZONES.
FORECAST SOUNDINGS INDICATE MOISTURE LACKING BELOW H75 SO NOT
LOOKING FOR MUCH IN THE WAY PCPN ATTM...BUT CANNOT RULE OUT
SPRINKLES AND WILL ADD IN POTENTIAL FOR VALLEY/GREELEY COUNTIES.
MID LEVEL SHORTWAVE TROUGH AXIS PASSES SATURDAY NIGHT AND HEIGHTS
GRADUALLY BEGIN TO RISE ON SUNDAY. LLVL FLOW REMAINS WEAK AS SFC
RIDGE SLOWLY TREKS EAST AND MODELS INDICATE POTENTIAL FOR
INCREASING MID/HIGH CLOUDS. NOT LOOKING AT MUCH WARMING JUST
YET...WITH HIGHS IN THE MID/LOW 50S. THE COOLER AIRMASS SHIFTS
EAST OF THE MISSOURI RIVER SUNDAY NIGHT WITH TEMPS MODERATING MORE
SO HEADING INTO THE WORKWEEK.
.LONG TERM...MONDAY THROUGH THURSDAY. WHILE THE EVOLUTION OF
HURRICANE SANDY AND THE EXTENT OF EAST COAST IMPACTS WILL GARNER THE
BRUNT OF NATIONAL ATTENTION NEXT WEEK...IT STILL APPEARS THE CENTRAL
PLAINS WILL QUIETLY EXPERIENCE SEVERAL DAYS OF DRY...TRANQUIL...AND
SEASONABLY MILD CONDITIONS INCLUDING HALLOWEEN. ANY CHANGES TO THE
PREVIOUS FORECAST...IF ANY AT ALL DURING PERIODS...WERE VERY MINOR AND
PRIMARILY INVOLVED A VERY SLIGHT 1-2 DEGREE UPWARD NUDGE IN DAILY
HIGH TEMPERATURES. IN GENERAL...DAILY HIGHS ARE FORECAST TO BE
WITHIN A FEW DEGREES EITHER SIDE OF NORMALS...SO ALL IN ALL TYPICAL
MID-FALL WEATHER.
STARTING WITH MONDAY/MONDAY NIGHT...AGREEMENT BETWEEN THE 00Z
ECMWF/GFS SOLUTIONS IS FAIRLY SIMILAR...ALTHOUGH THE EC SUGGESTS A
BIT STRONGER MID LEVEL RIDGE WILL EDGE TOWARD THE AREA WHILE BECOMING
CENTERED ALONG AN AXIS FROM THE DESERT SOUTHWEST TO THE NORTHERN
ROCKIES...WHILE THE GFS WHICH IS FARTHER EAST WITH SANDY KEEPS MORE
OF A BROAD NORTHWEST FLOW INTACT OVER THE REGION. HOWEVER...EVEN THE
GFS SOLUTION KEEPS ANY CLIPPER-TYPE SHORTWAVE SYSTEMS AND ASSOCIATED
MINOR PRECIPITATION EVENTS NO CLOSER THAN A CORRIDOR FROM SOUTH
DAKOTA THROUGH IA. HIGH TEMPS ARE FORECAST TO RANGE MID 50S
NORTHEAST TO LOW 60S SOUTHWEST...WITH OVERNIGHT LOWS MAINLY
MID-UPPER 30S.
TUESDAY/TUESDAY NIGHT...OVERALL VERY LITTLE CHANGE AS THE DEEP
TROUGH ASSOCIATED WITH SANDY DOMINATES THE EASTERN CONUS...WHILE THE
CENTRAL PLAINS REMAINS UNDER NORTH-NORTHWEST FLOW ON THE EASTERN
PERIPHERY OF THE ROCKY MOUNTAINS RIDGE AXIS. HIGH TEMPS ARE
ADVERTISED VERY SIMILAR TO MONDAY...RANGING MID 50S NORTHEAST TO MID
60S SOUTHWEST.
WEDNESDAY/WEDNESDAY NIGHT...THE BLOCKING PATTERN REMAINS FIRMLY IN
PLACE...AS THE MID LEVEL RIDGE AMPLIFIES EVEN MORE OVER THE CENTRAL
CONUS IN BETWEEN THE EASTERN TROUGH AND THE NEXT UPSTREAM TROUGH
MOVING ONTO THE PACIFIC COAST. BARRING MAJOR CHANGES...HALLOWEEN
WEATHER CONDITIONS DON/T GET MUCH MORE TRANQUIL THAN THIS...WITH
AFTERNOON HIGHS RANGING UPPER 50S NORTHEAST TO MID 60S
SOUTHWEST...AND EVENING READINGS SETTLING INTO THE 40S FOR
TRICK-OR-TREATERS.
THURSDAY...THE HEART OF THE EXPANSIVE NORTH-SOUTH MID LEVEL RIDGE
AXIS SHOULD EDGE EAST A BIT MORE TOWARD THE CENTRAL PLAINS FROM THE
ROCKIES...AS THE UPSTREAM WEST COAST WAVE FINALLY STARTS MAKING A
BIT OF EASTWARD PROGRESS. YET AGAIN FORECAST HIGH TEMPS ARE ALMOST
IDENTICAL TO THE PREVIOUS DAY...RANGING UPPER 50S NORTHEAST TO MID
60S SOUTHWEST ACROSS THE CWA.
LOOKING BEYOND THE OFFICIAL FORECAST PERIOD...THE NEXT HALFWAY
DECENT CHANCE OF PRECIPITATION...AND LIKELY IN THE FORM OF RAIN AND
NOT SNOW...SHOULD ARRIVE GENERALLY DURING THE NEXT FRIDAY
NIGHT-SATURDAY TIME FRAME AS THE WESTERN TROUGH FINALLY TRACKS INTO
THE PLAINS.
&&
.AVIATION...06Z KGRI TAF. WILL SAY OFF THE TOP THAT WHILE
CONFIDENCE IS QUITE HIGH THAT VISIBILITY WILL REMAIN UNRESTRICTED
AND THAT WINDS WILL AVERAGE AROUND 10KT OR LESS THROUGH THE
PERIOD...THE CONFIDENCE IN CEILING TRENDS IS WELL BELOW AVERAGE
DUE TO THE EXTREMELY POOR HANDLING OF AN EXPANSIVE MVFR STRATUS
DECK BY SEVERAL FORECAST MODELS AND ASSOCIATED NUMERICAL GUIDANCE.
STARTING OUT THE PERIOD...KGRI SITS UNDER THIS STRATUS BASED
AROUND 2500 FT AGL...WHILE AREAS BOTH 60-70 MILES EAST AND
SOUTHWEST OF THE TERMINAL ARE CURRENTLY VFR AND FREE OF THIS
STRATUS. ALTHOUGH IT IS NOT OUT OF THE QUESTION THAT RAPID CLEARING
COULD TAKE PLACE SOMETIME DURING THE NEXT 12 HOURS...AM GOING TO
KEEP THE PESSIMISTIC TREND FROM PREVIOUS FORECASTS AND KEEP THIS
MVFR CEILING IN PLACE THROUGH MOST OF THE PERIOD...ALTHOUGH
SUPPOSE A SLIGHT RISING OF THIS CEILING TO LOW-END VFR LEVELS
BETWEEN 3-4 THOUSAND FEET IS CERTAINLY NOT OUT OF THE QUESTION.
WILL ADVERTISE A RETURN TO VFR CEILING BY EARLY FRIDAY
EVENING...BUT AGAIN CONFIDENCE IS EXTREMELY LOW EVEN FOR JUST THE
FIRST 6-12 HOURS SO STAY TUNED FOR MODIFICATIONS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
316 AM CDT FRI OCT 26 2012
.DISCUSSION...
HANDLING CLOUDS OVER THE NEXT SEVERAL DAYS AND THE AFFECT ON
TEMPERATURES IS THE PRIMARY FORECAST CONCERN...WITH LIGHT PRECIP
CHANCE SATURDAY NIGHT A SECONDARY ISSUE.
BROAD BUT DEEP UPPER TROUGH OVER THE MIDDLE OF THE COUNTRY WILL
GRADUALLY TRANSLATE EASTWARD OVER THE WEEKEND...WITH SHALLOW RIDGE
BUILDING OVER THE ROCKIES FOR ALL OF NEXT WEEK. THIS LEAVES OUR PART
OF THE COUNTRY UNDER NORTHWEST FLOW ALOFT FOR THE BULK OF THE 7-DAY
FORECAST. A COUPLE OF SHORTWAVES WILL SWING THROUGH MID AMERICA OVER
THE NEXT SEVERAL DAYS...BRINGING A SMALL CHANCE OF PRECIPITATION TO
OUR AREA SATURDAY OR SATURDAY NIGHT. A GRADUAL WARMING TREND ALSO
LOOKS ON TRACK...WITH TEMPERATURES APPROACHING NORMAL VALUES IN THE
UPPER 50S OR LOWER 60S BY MID NEXT WEEK.
FOR TODAY...HIGH PRESSURE IN THE HIGH PLAINS WILL WORK EAST THROUGH
THE DAY BRINGING LIGHTER WINDS AND LITTLE MIXING. THUS ANY CLOUD
COVER CURRENTLY IN THE AREA WILL LIKELY HANG AROUND. HOWEVER...A
LARGE AREA OF CLEARING SKIES WAS NOTED THIS MORNING SPREADING FROM
NORTH TO SOUTH ACROSS MUCH OF EASTERN NEBRASKA AND WESTERN IOWA.
CLOUDS TO THE WEST AND NORTH WERE STILL WIDESPREAD AND EXPECT THESE
TO EXPAND EAST AND SOUTH WITH TIME TODAY. SO WILL PLAY THE
PESSIMISTIC SIDE OF THINGS AND KEEP MORE CLOUDS AND LOWER
TEMPERATURES THAN PREVIOUS FORECAST. STILL SHOULD SEE HIGHS CLOSE
TO 40 NORTH TO THE LOW TO MID 40S SOUTH.
SURFACE HIGH WILL SLIDE EAST BY SATURDAY MORNING AS SHORTWAVE DIVES
INTO THE HIGH PLAINS AND GENERATING SURFACE LOW PRESSURE. SOUTH
WINDS WILL RETURN TO THE AREA...AND MID AND HIGH CLOUDS WILL BE ON
THE INCREASE IN BROAD WARM ADVECTION REGIME AHEAD OF THE LOW. THOUGH
MODELS AND MOS OUTPUT SUGGESTS LOWER CLOUDS WILL BE GONE BY
TONIGHT...SOUTH TO SOUTHEAST FLOW IS NOT CONDUCIVE TO THIS. SO IF
LOWER CLOUDS SPREAD BACK OVER OUR AREA TODAY...DO NOT EXPECT THEM
TO LEAVE AHEAD OF LOW PRESSURE SATURDAY. BUT IN SENSIBLE WEATHER
TERMS...MOSTLY CLOUDY SKIES SHOULD RULE SATURDAY...WHETHER HIGH OR
LOW CLOUDS...AND SIGNIFICANT WARMING IS NOT EXPECTED. WILL TRIM
HIGHS BACK INTO THE 40S FOR MOST OF THE AREA...CLOSER TO GFS MOS
NUMBERS.
DYNAMIC LIFT WITH APPROACHING LOW/UPPER WAVE WILL INCREASE MARKEDLY
SATURDAY EVENING ACROSS EASTERN SOUTH DAKOTA AND NORTHEAST NEBRASKA.
PRECIPITATION SHOULD COMMENCE EARLY IN THE EVENING IN OUR FAR
NORTHWEST COUNTIES...BUT DRY LAYER BETWEEN LOW AND MID CLOUDS COULD
DELAY ONSET SOMEWHAT. FORECAST SOUNDINGS AND PARTIAL THICKNESS
PROGS SUGGEST A WARM LAYER NEAR THE SURFACE WILL EVENTUALLY COOL AS
PRECIP FALLS...SO A RAIN TO SNOW TRANSITION LOOKS LIKELY.
ACCUMULATION OF SNOW APPEARS MINIMAL IN NEBRASKA...WITH BEST LIFT
OVER SOUTH DAKOTA. CURRENT FORECAST LOOKS ON TRACK.
WEST OR NORTHWEST FLOW ON BACK SIDE OF SYSTEM SHOULD BRING CLEARING
SKIES AND WARMER TEMPERATURES ON SUNDAY. SHOULD SEE HIGHS EXCEEDING
50.
A COUPLE MORE SHORTWAVES AND ASSOCIATED WINGS OF WARM ADVECTION WILL
MOVE THROUGH THE NORTHERN PLAINS SUNDAY NIGHT AND MONDAY
NIGHT...SPREADING MID AND HIGH CLOUDS THROUGH THE REGION. THE SECOND
WAVE MONDAY NIGHT LOOKS TO BE THE STRONGEST...DEVELOPING A SURFACE
LOW IN THE PLAINS AND TRIGGERING LIGHT PRECIPITATION TO OUR NORTH.
WILL KEEP OUR FORECAST DRY...BUT WOULD NOT BE SURPRISED TO SEE
LIGHT RAIN BREAK OUT OVER OUR EASTERN AREAS MONDAY NIGHT.
OTHERWISE MAINLY CLOUDY CONDITIONS AT NIGHT SHOULD KEEP LOWS ABOVE
FREEZING WITH SOME SUNSHINE EACH DAY PUSHING HIGHS ABOVE 50. WILL
NOT CHANGE WEDNESDAY AND THURSDAY FORECAST AS UPPER RIDGING PUSHES
CLOSE TO OUR AREA...SO HIGHS APPROACHING 60 LOOK ON TRACK.
DERGAN
&&
.AVIATION...
06Z TAFS FOR KOMA...KLNK...KOFK
LATEST IR SAT IMAGERY INDCS SOME CLEARING TAKING PLACE IN THE MVFR
DECK THIS EVNG. THE RUC AND HRRR APPEAR TO BE PICKING UP ON THIS
TREND AND WILL GENERALLY USE THIS GUIDANCE FOR THE NEXT 6-10 HOURS
OF THE TAF. THE CLEARING SHOULD MOV INTO LNK/OMA PRIOR TO 07Z AND
MODEL GUIDANCE INDCS THAT IT BACKS TO THE WEST AND GETS TO AROUND
OFK BY 08Z. OTHERWISE NW SFC WINDS AOB 12 KT WILL CONT FOR THE
REST OF THE NIGHT. REGARDLESS OF HOW MUCH CLEARING TAKES PLACE
TONIGHT WE SHOULD SEE SOME REDEVELOPMENT OF THE CLOUDS ON FRI
MORNING AS MIXING INCREASES. THIS COULD BE BKN AT OFK/LNK WHILE
OMA MAY STAY SCT. WINDS WILL GO LIGHT AND VARIABLE LATE IN THE
PERIOD AS THE SFC HIGH TO THE WEST DEVELOPS INTO THE AREA BY 03Z
SAT.
BOUSTEAD
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1154 PM CDT THU OCT 25 2012
.AVIATION...
00Z TAFS FOR KOMA...KLNK...KOFK
LATEST IR SAT IMAGERY INDCS SOME CLEARING TAKING PLACE IN THE MVFR
DECK THIS EVNG. THE RUC AND HRRR APPEAR TO BE PICKING UP ON THIS
TREND AND WILL GENERALLY USE THIS GUIDANCE FOR THE NEXT 6-10 HOURS
OF THE TAF. THE CLEARING SHOULD MOV INTO LNK/OMA PRIOR TO 07Z AND
MODEL GUIDANCE INDCS THAT IT BACKS TO THE WEST AND GETS TO AROUND
OFK BY 08Z. OTHERWISE NW SFC WINDS AOB 12 KT WILL CONT FOR THE
REST OF THE NIGHT. REGARDLESS OF HOW MUCH CLEARING TAKES PLACE
TONIGHT WE SHOULD SEE SOME REDEVELOPMENT OF THE CLOUDS ON FRI
MORNING AS MIXING INCREASES. THIS COULD BE BKN AT OFK/LNK WHILE
OMA MAY STAY SCT. WINDS WILL GO LIGHT AND VARIABLE LATE IN THE
PERIOD AS THE SFC HIGH TO THE WEST DEVELOPS INTO THE AREA BY 03Z
SAT.
BOUSTEAD
&&
.PREV DISCUSSION... /ISSUED 928 PM CDT THU OCT 25 2012/
UPDATE...
UPDATED TO INCREASE OVERNIGHT LOWS AND CLOUDS
DISCUSSION...
LATEST IR IMAGERY CONTS TO INDC A FAIRLY EXPANSIVE STRATUS DECK
ACROSS THE REGION THIS EVENING. MODELS CONT TO STRUGGLE WITH THIS
DECK AND THE ONLY MODEL THAT APPEARS TO HAVE SOME HANDLE ON THE
SITUATION IS THE RAP. THE RAP INDCS THAT THE CLOUDS WILL CONT
THRU THE NIGHT AND ACTUALLY INTO FRI MRNG /ESPECIALLY IN THE WRN
FA/. THE IR IMAGERY DOES INDC SOME HOLES IN THIS DECK AROUND KYKN
AND KSUX THOUGH AND THIS WILL NEED TO BE MONITORED FOR THE CNTRL
AND ERN CWA OVERNIGHT. NEVERTHELESS WITH THE AMOUNT OF CLOUDS IT
APPEARS THAT OVERNIGHT LOWS NEED ADJUSTING UPWARD IN MOST
LOCATIONS WITH UPPER 20S TO LOWER 30S APPEARING REASONABLE.
OTHERWISE THE FORECAST APPEARED TO BE IN GOOD SHAPE.
THE UPDATES WILL BE OUT BY 930 PM.
BOUSTEAD
PREV DISCUSSION... /ISSUED 313 PM CDT THU OCT 25 2012/
SHORT TERM...TONIGHT THROUGH SUNDAY. MAIN FORECAST PROBLEM IN
THE VERY NEAR TERM IS AN EXPANDING DECK OF STRATUS THAT NO MODEL
EXCEPT THE RAP SEEMS TO BE HANDLING ALL THAT WELL. THUS...HAVE
TRENDED CLOUD GRIDS UPWARD TONIGHT...BUT AM STILL THINKING THAT
SOME OF THIS MAY DISSIPATE THIS EVENING AS MORE ANTICYCLONIC FLOW
CONTINUES TO TAKE HOLD ACROSS THE REGION. IT WILL PROBABLY BE A
COLD NIGHT WITH LOWS IN THE 20S AS SKIES SCATTER OUT. GIVEN THE
RECENT RAINS...THERE COULD BE PATCHY FOG OVERNIGHT...BUT PROBABLY
NOT A BIG ENOUGH OF CONCERN TO ADD TO THE GRIDS.
HIGH PRESSURE CONTINUES TO MOVE OFF THE HIGH PLAINS ON FRIDAY WITH
NORTHWESTERLY FLOW AND SOME MID AND HIGH CLOUDS. HIGH PRESSURE
DRIFTS OVER THE FORECAST AREA FRIDAY EVENING WITH A RETURN FLOW
SETTING UP ON SATURDAY.
A NEW AREA OF LOW PRESSURE DEVELOPS ACROSS SOUTHWEST SOUTH DAKOTA
THROUGH THE DAY SATURDAY WHILE AN UPPER WAVE MOVES THROUGH THE
NORTHERN PLAINS. WARM AIR ADVECTION COULD RESULT IN A FEW SHOWERS
NEAR THE SD/NE BORDER SATURDAY AFTERNOON...THEN SLIDING EAST
SOUTHEAST DOWN THE MISSOURI RIVER VALLEY SATURDAY NIGHT. THE NAM
IS CONSIDERABLY WARMER...WHICH IS PROBABLY TOO WARM. BUT...THERE
COULD BE A FEW RAIN SHOWER OR EVEN A SNOW FLAKE MIXED IN MAINLY
NORTH OF OMAHA SATURDAY NIGHT. DRY WEATHER IS EXPECTED ON SUNDAY.
LONG TERM...SUNDAY NIGHT THROUGH THURSDAY. MEDIUM RANGE MODELS
NOT SHOWING MUCH POTENTIAL FOR ANY PCPN THRU MOST OF NEXT WEEK.
OTHERWISE...LATEST GFS BLOCKING INDICES ADVERTISING UPSTREAM
BLOCKAGE DEVELOPING THRU DAY 7...ALLOWING FOR AMPLIFIED RIDGING
OVER THE ROCKIES/WRN HIGH PLAINS WITH 2 TROFS FLANKING THE CONUS.
THIS THEN LEADING TO THRUST OF COLD AIR DOWN THRU THE UPPER
MIDWEST/GREAT LAKES REGION REACHING ALL THE WAY DOWN TO THE SERN
STATES. AT THIS POINT THEN THE MAIN INTEREST IS HOW FAR WILL THE
WRN PERIPHERY OF CAA PUSH IT INTO THE CWA BEFORE AFOREMENTIONED
ROCKIES/WRN HIGH PLAINS RIDGE BUILDS IN. COMPARISON OF 1000-500MB
THKNS DAYS 5-7...ECM DETERMINIST PROGS CLEARLY SHOW IT TO BE THE
WARMER OF THE TWO. THIS ALSO REFLECTED THRU WARMER ECM MOS MAX/MIN
TEMPS RELATIVE TO THE MEX. GOING FCST APPEAR TO BE IN ACCORDANCE
WITH THE WARMER ECM SOLUTION...THUS SEE NO REASON TO MAKE ANY
CHANGE DEPICTING WARMING TREND IN THE EXTEND PDS.
DEE
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS RALEIGH NC
132 AM EDT FRI OCT 26 2012
.SYNOPSIS...
HIGH PRESSURE CENTERED TO OUR NORTHEAST WILL EXTEND DOWN THE MID
ATLANTIC COAST THROUGH FRIDAY. TROPICAL CYCLONE SANDY WILL TRACK
TOWARD THE NORTH OR NORTH NORTHEAST OFF THE SOUTHEAST AND CAROLINA
COAST FRIDAY THROUGH SUNDAY.
&&
.NEAR TERM /THROUGH FRIDAY NIGHT/...
AS OF 945 PM THURSDAY...
OUTSIDE OF SOME THIN CIRRUS FROM THE OUTER BANDS OF HURRICANE SANDY
DRIFTING ACROSS THE SOUTHEAST CWA...SKIES ARE MOSTLY CLEAR FOR MUCH
OF THE AREA. THE DEEP LAYER RIDGE REMAINS CENTERED ALONG THE EAST
COAST...WITH SURFACE HIGH PRESSURE EXTENDING WEST FROM THE ATLANTIC
ACROSS NC. EASTERLY WINDS JUST ABOVE THE SURFACE ARE LEADING TO THE
REDEVELOPMENT OF A MARINE LAYER OVER SOUTHEAST VA AS MOISTURE
ADVECTS SOUTHWEST BELOW AN INVERSION NOTED NEAR 925MB ON THE 00Z
KWAL RAOB. STRATUS SHOULD BEGIN TO SPREAD SOUTHWEST ACROSS THE CWA
AFTER MIDNIGHT..AND HRRR MOISTURE FIELDS SUGGEST THE STRATUS WILL
SPREAD ACROSS ALL BUT THE SOUTHERN PIEDMONT BY 12Z. HAVE ADJUSTED
SKY GRIDS TO BE A LITTLE MORE AGGRESSIVE...WITH ALL BUT THE COUNTIES
BORDERING THE YADKIN MOSTLY CLOUDY BY 12Z. OUTSIDE OF THE
STRATUS...PATCHY FOG IS POSSIBLE UNDER MOSTLY CLEAR SKIES AND NEARLY
CALM CONDITIONS.
TEMPS ARE CURRENTLY IN THE LOW TO MID 60S MOST EVERYWHERE...THOUGH
COOLING WILL SLOW AS THE STRATUS ROLLS IN. THUS...THE CURRENT
FORECAST OF 53-57 LOOKS ON TRACK. -BLS
FOR FRIDAY/FRIDAY NIGHT: WEATHER CONDITIONS SLOWLY START TO
DETERIORATE DURING THIS TIME FRAME. NC IS WITHIN THE MID LEVEL COL
AREA FRIDAY MORNING... WITH RIDGING TO THE ENE AND SW... THE LARGE
POLAR TROUGH TO OUR NW... AND THE APPROACHING CIRCULATION OF SANDY
TO OUR SSE. SANDY`S CENTER IS EXPECTED TO MOVE GENERALLY NORTHWARD
OVER AND THEN NORTH OF THE BAHAMAS THROUGH FRIDAY NIGHT. (PLEASE SEE
THE VERY LATEST OFFICIAL FORECASTS FROM THE NHC REGARDING SANDY.)
ITS LARGE CIRCULATION WILL START TO AFFECT NC FRIDAY NIGHT AS THE
STORM`S APPROACH AGAINST THE NARROWING RIDGE NOSING FROM MAINE INTO
NW NC QUICKLY INCREASES THE MSLP GRADIENT PARTICULARLY OVER SRN AND
ERN NC AS WE HEAD INTO FRIDAY NIGHT. BACKING UP TO FRIDAY... THE
MORNING CLOUDS AND FOG SHOULD VERY SLOWLY LIFT THROUGH THE
MORNING... BUT OVERALL EXPECT VARIABLY TO MOSTLY CLOUDY SKIES FOR
MOST OF THE DAY FROM RALEIGH SOUTH AND EAST... WITH A BIT MORE
SUNSHINE TO THE NW OVER THE TRIAD AREA. TEMPS ARE QUITE TOUGH GIVEN
THAT ANY BREAK IN THE CLOUDS WILL ALLOW FOR POCKETS OF HEATING TO
PUSH TEMPS WELL UP THROUGH THE UPPER 70S GIVEN THICKNESSES THAT ARE
NEARLY 20 METERS ABOVE NORMAL... WHILE LOCALIZED PERSISTENT CLOUD
COVER THROUGHOUT THE DAY WILL HOLD TEMPS DOWN INTO THE LOWER 70S.
WILL GO WITH HIGHS OF 73 NORTH-CENTRAL TO 76-77 SOUTHEAST WITH LOWER
THAN USUAL CONFIDENCE. EXPECT SKIES TO TREND QUICKLY TO OVERCAST
FRIDAY EVENING... BOTH WITH THE PERSISTENT ONSHORE FLOW ENCOURAGING
GREATER AND THICKER STRATUS DEVELOPMENT AREAWIDE... AND FROM
INCREASING MID AND HIGH CLOUDS AS SANDY`S EXHAUST CLOUD SHIELD
APPROACHES FROM THE SSE. CLOUDS MAY ACTUALLY BE THICKEST AND MOST
EXTENSIVE OVER THE WRN PIEDMONT AS THE MOIST EASTERLY LOW LEVEL FLOW
RIDES UP AND OVER THE LINGERING VULNERABLE SURFACE RIDGE CREATING
LOCALLY DEEPER MOIST ISENTROPIC UPGLIDE. WHILE PW VALUES ARE
EXPECTED TO BE TRENDING STEADILY UPWARD... TO 1.25-1.5 INCHES WHICH
IS AT OR ABOVE 150% OF NORMAL... ANY TROPICAL SHOWERS SHOULD BE
PATCHY GIVEN THE LACK OF STRONG FORCING AND LINGERING MID LEVEL DRY
AIR. WILL SLOW DOWN AND SLIGHTLY REDUCE POPS... GOING WITH PRIMARILY
SLIGHT CHANCE POPS AFTER SUNSET. MILD LOWS IN THE UPPER 50S TO LOWER
60S WITH BREEZY CONDITIONS DEVELOPING OVERNIGHT. -GIH
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 255 PM THURSDAY...
MODEL GUIDANCE IN GOOD AGREEMENT WITH THE TRACK OF TROPICAL CYCLONE
SANDY PARALLELING THE SE U.S. COAST THROUGH SUNDAY MORNING. SINCE
SANDY HAS AN EXPANSIVE WIND FIELD...WILL START SEEING AN INCREASE IN
MOISTURE TRANSPORT OFF THE ATLANTIC INTO CENTRAL NC FRIDAY NIGHT
THROUGH SATURDAY NIGHT...ABATING ON SUNDAY. THIS INFLUX OF MOISTURE
COUPLED WITH CONVERGENCE ALONG A 700 MB TROUGH OVER THE COASTAL
PLAIN AND INCREASING UPPER DIVERGENCE ALOFT SUPPLIED BY A
STRENGTHENING UPPER JET OVER THE EASTERN GREAT LAKES SUGGEST
CATEGORICAL POPS NEEDED FOR AREAS OF CENTRAL NC...BASICALLY ALONG
AND EAST OF I-95...SATURDAY AFTERNOON INTO EARLY SUNDAY. WILL LIKELY
SEE AREAS OF LIGHT RAIN DEVELOP PRIOR TO DAYBREAK IN THE FAR
EAST...AND MORE SO DURING THE MORNING HOURS SATURDAY BEFORE THE
ABOVE PARAMETERS COME TOGETHER TO CAUSE WIDESPREAD RAIN ASSOCIATED
WITH SANDY. CURRENTLY ADVERTISING RAINFALL AMOUNTS SATURDAY UNTIL
EARLY SUNDAY ALONG AND EAST OF THE I-95 CORRIDOR BETWEEN 1-2 INCHES.
THIS MAY BE CONSERVATIVE AS 00Z ECMWF SUGGEST TOTALS CLOSER TO 3
INCHES. OVER THE PIEDMONT....EXPECT A DEFINITIVE DECREASE IN POPS
BEYOND THE TRIANGLE AREA AS MOISTURE WILL NOT BE AS DEEP AND LIFT
NOT AS STRONG OVER THE WESTERN AND SOUTHERN PIEDMONT.
STILL...OVERCAST SKIES AND BLUSTERY NLY WINDS AND SPOTS OF RAIN WILL
MAKE IT A RAW PERIOD.
AS SANDY MOVES NWD OFFSHORE OF SC-NC LATE SATURDAY THROUGH
EARLY SUNDAY...EXPECT TO SEE AN INCREASE IN THE WINDS...ESPECIALLY
AFTER MIDNIGHT SATURDAY NIGHT WHEN SANDY MAKES ITS CLOSEST APPROACH
TO THE NC COAST (THOUGH STILL QUITE A DISTANCE OFFSHORE). POPULATED
THE WIND GRIDS WITH TCM WINDS FROM THE LATEST NHC TCM PRODUCT THEN
USED A REDUCTION FACTOR OF 30 PERCENT DUE TO SURFACE FRICTION. GUSTS
ACHIEVED BY UTILIZING RESEARCH CURRENTLY BEING CONDUCTED BY THE
C*STAR INITIATIVE (COLLABORATION BETWEEN NWS AND LOCAL
UNIVERSITIES). CURRENTLY EXPECT MAX GUSTS IN OUR FAR EASTERN COASTAL
PLAIN COUNTIES EARLY SUNDAY MORNING 30-33KTS. WHILE CRITERIA WILL
LIKELY NOT BE MET...MAY STILL NEED A WIND ADVISORY BY SUNDAY AS
CONTINUED SUSTAINED WINDS AND AN INCREASINGLY MOIST/SATURATED TOP
SOIL MAY LEAD TO DOWNED TREES AND POWER OUTAGES.
MODEL GUIDANCE IN RELATIVELY GOOD AGREEMENT SUNDAY THROUGH SUNDAY
NIGHT...TAKING SANDY MORE TO THE NE IN RESPONSE TO A S/W ROUNDING
THE BASE OF A DEEP UPPER TROUGH OVER THE GREAT LAKES-OH VALLEY. DID
NOTE THAT THE ECMWF IS ABOUT 20-25MB DEEPER THAN THE GFS AND REMAINS
CLOSER TO THE COAST. THIS NE JOG OF SANDY SHOULD ALLOW THE RAIN AXIS
TO SHIFT MORE TO THE N NE ON SUNDAY. THUS SHOULD SEE RAIN
INTENSITY/COVERAGE BEGIN TO DROP OFF OVER OUR COASTAL PLAIN
COUNTIES...ESPECIALLY BY AFTERNOON. STILL EXPECT WINDS TO REMAIN
QUITE BREEZY DUE TO THE STRENGTH OF SANDY AND A STRONG CANADIAN HIGH
OVER ONTARIO. SUSTAINED WINDS 15-20KTS PROBABLE WITH GUSTS WELL INTO
THE 20S.
TEMPS THROUGH THE PERIOD WILL UNDERGO A COOLING TREND. MAX TEMPS
SATURDAY MAINLY IN THE 60S TO AROUND 70...COOLING INTO THE UPPER 50S
AND 60S SUNDAY. MIN TEMPS SATURDAY NIGHT MAINLY IN THE 50S...COOLING
INTO THE LOW-MID 40S BY EARLY MONDAY.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 250 PM THURSDAY...
SANDY WILL BE THE DOMINATE WEATHER FEATURE THIS PERIOD. MODEL
GUIDANCE STILL OFFERING VARYING SOLUTIONS. ECMWF HAS BEEN THE MOST
CONSISTENT WHILE THE GFS HAS SHOWN AN OVERALL TREND TOWARD THE
ECMWF. THUS WILL LEAN HEAVILY ON THE ECMWF THROUGH THE PERIOD.
S/W IN THE NORTHERN STREAM THAT INITIALLY PUSHES SANDY TO THE NE
WILL EVENTUALLY DRAW SANDY BACK TO THE NW AS IT ATTAINS A NEGATIVE
TILT. THE ECMWF MAKES THIS TURN A LOT SOONER/SHARPER COMPARED TO
THE GFS. THE TRUTH MAY LIE SOMEWHERE IN BETWEEN.
WITH SANDY PROJECTED TO LIE TO OUR NE-N...EXPECT CONTINUED WNW FLOW
ACROSS OUR REGION. DEEP CYCLONIC CURVATURE WILL LIKELY MAINTAIN
CLOUDINESS AND POSSIBLY PATCHES OF LIGHT RAIN OVER OUR FAR N-NE
COUNTIES MONDAY THROUGH EARLY TUESDAY. FARTHER SOUTH...DOWNSLOPE
COMPONENT OF THE LOW-MID LEVEL WINDS SHOULD AID TO SCOUR OUT THE
MOISTURE AND LEAD TO CLEARING SKIES. LOW LEVEL FLOW WILL ALSO
ADVECT MUCH COOLER AIR INTO CENTRAL NC. LOW LEVEL THICKNESSES
TUESDAY MORNING CLUSTER AROUND 1298-1303M...AND 1290-1295M WEDNESDAY
MORNING. HISTORICALLY...THESE VALUES CLUSTER IN THE UPPER 20S TO
AROUND 30. STRONG MIXING AND POSSIBILITY OF CLOUDINESS SHOULD KEEP
TEMPS UP A BIT. MAY SEE BETTER POTENTIAL FOR A LIGHT FREEZE
WEDNESDAY MORNING IN SECTIONS OF THE PIEDMONT. OTHERWISE WITH
THICKNESSES 30-35M BELOW NORMAL...EXPECT MAX TEMPS 10-15 DEGREES
BELOW NORMAL MONDAY-WEDNESDAY WITH SOME MODIFICATION BY THURSDAY.
AFTERNOON TEMPS IN THE 50S EXPECTED FOR MOST OF NEXT WEEK.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 130 AM FRIDAY...
24 HOUR TAF PERIOD:
LOW-LEVEL EAST-NORTHEASTERLY WINDS WILL CONTINUE TO ADVECT A MARINE
LAYER BELOW A NEAR SURFACE BASED INVERSION NOTED ON NEARBY
RAOBS. THIS IFR TO LIFR STRATUS HAS ALREADY MADE IT TO KRWI...AND
WILL CONTINUE TO SPREAD WEST...IMPACTING KRDU AND KFAY AOA 08 TO
09Z...AND QUITE POSSIBLY KINT AND KGSO JUST BEFORE DAYBREAK.
CIGS WILL BE SLOW TO LIFT AND BREAK UP THIS MORNING...WITH SUB-VFR
CONDITIONS THROUGH AT LEAST 15Z WITH VFR CONDITIONS EXPECTED BY
18Z...PERSISTING THROUGH THE AFTERNOON.
OUTLOOK:
AVIATION CONDITIONS ARE EXPECTED TO DETERIORATE AS WHAT IS NOW
HURRICANE SANDY STARTS TO MOVE FROM THE BAHAMAS NORTHWARD OFF THE
SOUTHEAST COAST THROUGH FRIDAY NIGHT... THEN NORTHEASTWARD OFF THE
CAROLINA COAST SATURDAY THROUGH SUNDAY. MVFR/IFR CONDITIONS ARE
EXPECTED TO DOMINATE AT ALL SITES STARTING LATE FRIDAY NIGHT. THE
MOST ADVERSE AVIATION CONDITIONS WILL OCCUR FROM MIDDAY SATURDAY
THROUGH AT LEAST SUNDAY NIGHT... ALTHOUGH DURATION OF ADVERSE
CONDITIONS WILL DEPEND ON THE EVENTUAL TRACK OF SANDY. THE HIGHEST
CONFIDENCE IN POOR AVIATION WEATHER IS AT KRWI/KFAY WHERE HEAVY RAIN
IS POSSIBLE... AND THIS RAIN MAY EXPAND AS FAR WEST AS KRDU. STRONG
GUSTY WINDS FROM THE NNE ARE LIKELY AREAWIDE BUT ESPECIALLY AT
KRDU/KRWI/KFAY... AND LOW LEVEL WIND SHEAR AND/OR SIGNIFICANT
MECHANICAL TURBULENCE IS ALSO POSSIBLE. VFR CONDITIONS ARE EXPECTED
TO RETURN MONDAY... HOWEVER WINDY CONDITIONS MAY PERSIST.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD/BLS
SHORT TERM...WSS
LONG TERM...WSS
AVIATION...CBL/HARTFIELD
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
150 AM EDT FRI OCT 26 2012
.SYNOPSIS...
A STRONG RIDGE OF HIGH PRESSURE ALOFT WILL PERSIST THROUGH FRIDAY
BEFORE GIVING WAY TO A COLD FRONT WHICH WILL BRING A SLIGHT
CHANCE OF SHOWERS AND MUCH COOLER CONDITIONS TO THE REGION FOR THE
WEEKEND. MEANWHILE...HURRICANE SANDY IS CURRENTLY EXPECTED TO
MOVE NORTHWARD THROUGH THE ATLANTIC OCEAN THIS WEEKEND BEFORE
TRACKING TO NEAR THE MID ATLANTIC COAST EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 835 PM EDT THURSDAY...
ALTHOUGH 00Z SOUNDINGS REMAIN QUITE DRY ACROSS THE REGION...LOW
LEVEL SE FLOW STARTING TO GENERATE SOME LOW CLOUDS ALONG THE SRN
BLUE RIDGE/FOOTHILLS THIS EVENING WITH THIS STRATO-CU SLOWLY
PUSHING NORTH ACROSS PARTS OF NW NC. LATEST NAM ON TRACK WITH THIS
MOISTURE UNDER THE INVERSION AND SPREADS CLOUDS NORTHWARD ACROSS
SW VA BY MORNING. IN ADDITION...MORE EASTERLY FLOW DEVELOPING
ACROSS THE PIEDMONT LOOKS TO DRIVE LOW LEVEL ATLANTIC MOISTURE
WEST...WITH THIS MARINE LAYER TYPE CANOPY POSSIBLY PUSHING INTO
THE PIEDMONT AND NORTHERN AREAS LATE. GIVEN A BIT OF ADDED
UPSLOPE...BOTH THE RAP AND NAM DEVELOP FOG AND EVEN SOME DRIZZLE
OVERNIGHT OUT EAST DESPITE A VERY SHALLOW LAYER OF MOISTURE.
HOWEVER THIS LOOKS OVERDONE GIVEN CURRENT DEGREE OF DRYNESS AND
LOW DECK STILL WELL TO THE EAST/NE. THUS HAVE QUICKLY BEEFED UP
CLOUDS OVER THE SW THIS EVENING/OVERNIGHT AND ONLY INCLUDED MORE
FOG AND PERHAPS A BIT OF -DZ NEAR DAWN NE SECTIONS. ELSW EXPECT
SE WVA AND PERHAPS THE FAR SE COUNTIES TO REMAIN CLEAR WITH SKIES
BECOMING PARTLY/MOSTLY CLOUDY ELSW OVERNIGHT. BUMPED UP TEMPS A
CAT OR SO ALONG THE RIDGES...WHILE LOWERING VALLEYS AND EAST WHERE
ONSHORE FLOW SHOULD ALLOW THINGS TO COOL A LITTLE MORE AS DEWPOINTS
REMAIN RATHER LOW UNTIL FRIDAY.
PREVIOUS DISCUSSION AS OF 400 PM EDT THURSDAY...
SURFACE OBSERVATIONS AND SATELLITE IMAGERY INDICATE MAINLY CLEAR
SKIES ACROSS THE FORECAST REGION THIS AFTERNOON...AND WE CAN
EXPECT THESE CONDITIONS TO CONTINUE THROUGH THE REMAINDER OF
THURSDAY...UNDER LIGHT EASTERLY WINDS. DEFINITELY SET A NEW RECORD
HIGH TEMPERATURE TODAY FOR DANVILLE...AND AT LEAST TIED ONE FOR
BLUEFIELD. STILL MAY AT LEAST TIE A RECORD FOR BLACKSBURG WITH
ANOTHER HOUR OR TWO OF DAYTIME HEATING.
WINDS ARE EXPECTED TO BECOME MORE NORTHEASTERLY OVERNIGHT...
RESULTING IN INCREASED CLOUD COVER AS ATLANTIC MOISTURE MOVES IN
FROM THE WASHINGTON DC AREA...AND BECOMES WEDGED AGAINST THE BLUE
RIDGE BY SUNRISE TOMORROW. BELIEVE THESE LOW CLOUDS...ALONG WITH
PATCHY FOG...BUILDING ACROSS THE PIEDMONTS WILL KEEP OVERNIGHT
LOWS A LITTLE WARMER THAN LAST NIGHT...WITH MINIMUM TEMPERATURES
EXPECTED TO RANGE FROM THE MID/UPPER 40S ACROSS THE MOUNTAINS...TO
THE MID 50S FURTHER EAST.
CLOUD COVER WILL BE SLOW TO BREAK UP ON FRIDAY MORNING AND
AFTERNOON AS CIRRUS FROM HURRICANE SANDY BEGINS TO BUILD INTO THE
AREA. AS SUCH...EXPECT FRIDAY HIGH TEMPERATURES TO BE NOTICEABLY
COOLER...ALTHOUGH STILL WARM FOR THIS TIME OF YEAR...WITH AFTERNOON
HIGHS RANGING FROM THE UPPER 60S TO THE LOW 70S.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
AS OF 155 PM EDT THURSDAY...
AS SANDY PROGRESSES NORTH ALONG THE EAST COAST...ONSHORE EASTERLY
LOW LEVEL FLOW WILL INCREASE. ANTICIPATE AN INCREASE IN LOW LEVEL
CLOUD COVER AND THE ONSET OF SOME LIGHT RAIN THAT WILL INCREASE IN
COVERAGE FRIDAY NIGHT THROUGH SATURDAY. LATE IN THE DAY
SATURDAY...THE APPROACH OF A COLD FRONT WILL BRING RAIN SHOWERS TO
WESTERN PARTS OF THE AREA. AS WE CONTINUE INTO SUNDAY...SANDY WILL
BE LOCATED OFF THE COAST OF THE CAROLINAS AND THE ONSHORE FLOW
WILL TURN MORE NORTHEAST AND WE LOSE THE UPSLOPE COMPONENT SO THAT
PRECIPITATION WILL BECOME LIMITED IN THE EAST. COVERAGE OF SHOWERS
WILL INCREASE IN THE WEST AS THE COLD FRONT GETS CLOSER.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 515 PM EDT THURSDAY...
MADE UPDATES TO POPS/SKY AND WINDS TO REFLECT THE POTENTIAL TO SEE
MUCH MORE COVERAGE OF UPSLOPE PRECIP WEST INCLUDING SNOW ALONG
THE WESTERN SLOPES AND RAINFALL OVER THE NORTH UNDER THE CYCLONE
TO THE NE. ALSO WINDS COULD BE QUITE AN ISSUE BY TUESDAY WITH
GUSTS INTO ADVISORY OR WARNING LEVELS POSSIBLE ESPCLY MOUNTAINS.
WILL UPDATE THE HWO TO REFLECT THE WIND AND SNOW POTENTIAL FOR
EARLY NEXT WEEK.
AS OF 1145 AM EDT THURSDAY...
THE FOCUS ON THIS SECTION OF FORECAST CONTINUES TO BE WHAT TRACK
OF THE LOW THAT HAD BEEN NAMED SANDY TAKES...AND ITS IMPACT...OR
LACK THEREOF ON OUR WEATHER. WILL CONTINUE TO HAVE OUR FORECAST
REFLECT THAT OF HPC IN THIS TIME PERIOD. THIS SOLUTION LEANS
TOWARD THAT OF THE GFS THAT MAINTAINS THE LOW OFF THE COAST FOR A
LONGER PERIOD OF TIME BEFORE STARTING A WESTWARD TREND TOWARD NEW
ENGLAND...WITH THE MID-WEST UPPER TROUGH REMAINING A SEPARATE
ENTITY FOR A LONGER PERIOD OF TIME WITH ITS EASTERN FLANK AND
ASSOCIATED COLD FRONT OVER OUR REGION.
OUR FORECAST WILL REFLECT ONE THAT HAS ITS GREATEST FOCUS ON STRONG
NORTHWEST FLOW UPSLOPE RAIN/SNOW SHOWERS OCCURRING FROM SOUTHEAST
WEST VIRGINIA...SOUTH INTO THE NORTHERN MOUNTAINS OF NORTH CAROLINA.
AN ADDITIONAL AREA OF PRECIPITATION WILL BE ALONG AND NORTHEAST OF A
LINE FROM LEXINGTON VA TO HALIFAX VA. HERE THE WESTERN EXTENT OF
PRECIPITATION ASSOCIATED WITH THE REMNANTS OF SANDY IS EXPECTED TO
OCCUR ACROSS OUR REGION. GRANTED...AS WEATHER FORECAST MODELS
PROVIDE ADDITIONAL OUTPUT...THE PLACEMENT OF THIS AREA OF
PRECIPITATION MAY IN REALITY COVER MORE OR LESS OF THE FORECAST AREA.
REGARDLESS OF GFS OR ECMWF...THE MODELS HAVE BEEN TRENDING TOWARD
COLDER 850 MB AND SURFACE TEMPERATURES YIELDING A GREATER POTENTIAL
FOR SNOW TO BE IN THE FORECAST...ESPECIALLY FOR THE NORTHWEST FLOW
UPSLOPE ACTIVITY IN THE WEST. BOTH MONDAY NIGHT AND TUESDAY
NIGHT...UPPER 20S IN THE MOUNTAINS AND LOW TO MID 30S IN THE
PIEDMONT ARE CURRENTLY FORECAST. SO FAR...THE GROWING SEASON HAS
ENDED FOR ONLY GREENBRIER COUNTY WV AND BATH COUNTY VA. IF THESE
FORECAST LOWS ARE REALIZED...THE REMAINDER OF THE AREA SHOULD SEE AN
END TO ITS GROWING SEASON.
SURFACE WINDS MAY BE AT OR JUST A BIT BELOW WIND ADVISORY CRITERIA.
AGAIN...AS WE GET CLOSER TO THIS TIME PERIOD...WE WILL HAVE GREATER
CONFIDENCE IN SPEEDS. ALSO...WHILE NOT AT ADVISORY LEVELS...WIND
CHILLS IN THE MOUNTAINS WILL DROP INTO THE TEENS WITH 20S IN THE
PIEDMONT.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 150 AM EDT FRIDAY...
DETERIORATING AVIATION CONDITIONS EXPECTED THIS TAF VALID PERIOD.
INCREASINGLY DEEP EASTERLY MARITIME FLOW DEVELOPING ACROSS EASTERN
VA AND PROGRESSING STEADILY TOWARD WESTERN VA THIS HOUR. EXTENSIVE
AREA OF LOW CLOUDS WITH MOSTLY MVFR CIGS AND MVFR VSBYS SPREADING
WEST. AT 06Z...THE LEADING EDGE OF THIS CLOUD COVER HAD MADE IT TO
JUST EAST OF THE BLUE RIDGE...ROUGHLY FROM MRB-CHO-FVX. USING THE
TIME/DISTANCE TOOL SHOWS THIS TO REACH ROA IN ABOUT FOUR HOURS...OR
ROUGHLY NEAR DAYBREAK. HAVE MADE SOME MAJOR CHANGES TO THE TAFS THIS
VALID PERIOD...SHOWING WIDESPREAD MVFR CIGS IN PLACE THROUGHOUT TAF
VALID PERIOD FOR ALL VA TAF SITES WITHIN THE RNK CWA...ONCE THE
CLOUDS SPREAD INTO THE SITE FROM THE EAST. THIS WILL REACH BCB
LAST...AND MAY ENCOUNTER SOME DIFFICULTY LIFTING UP THE HIGH TERRAIN
BETWEEN ROA AND BCB,,,BUT EXPECT AT LEAST BKN CONDITIONS THERE AS
WELL. FOR THE WV SITES...NOT AS CLEAR CUT A SITUATION. HOWEVER...LOW
CLOUDS HAVE CREPT FROM COVINGTON VA WEST THROUGH THE I-64 CORRIDOR
INTO LWB. HAVE PLAYED FOR MVFR CIGS FOR LWB LATE TONIGHT FORWARD IN
LIEU OF DENSE EARLY MORNING FOG. AS NOTED...NOT TOTALLY CONFIDENT
ABOUT THIS. FOR BLF...NOT EXPECTING ANY CIG/VSBY ISSUES THIS TAF
VALID PERIOD. THAT SHOULD HOLD OFF UNTIL AFT 06Z SAT. FOR
WINDS...EXPECT E-NE WINDS 5-7KTS...EXCEPT VRB FOR WV SITES.
AS OF 740 PM EDT THURSDAY...
GUIDANCE HAS BACKED OFF THE NOTION OF LOW CIGS/VIS ALONG THE BLUE
RIDGE OVERNIGHT. VERY DRY ATMOSPHERE WILL PROBABLY TAKE LONGER TO
MOISTEN UP AND THE EASTERLY COMPONENT MAY NOT BE STRONG ENOUGH OR
CONSISTENT ENOUGH CREATE A THICK ENOUGH LAYER OF SUFFICIENT RH. ALTHOUGH
THE SHIELD OF STRATUS OBSERVED LAST NIGHT MAY CREEP FURTHER SOUTH
AND WEST THAN LAST NIGHT...HARD TO FIGURE EXTENSIVE IFR CIG/VIS
WILL INVADE LYH/ROA/DAN CONSIDERING CURRENT CONDITIONS. THIS LOOKS
TO BE MORE OF A POSSIBILITY FRIDAY NIGHT. CAN`T RULE OUT SOME MVFR
VIS TONIGHT LWB/BCB. MORE SURFACE CONVERGENCE TOMORROW THANKS TO A
BETTER UPSLOPE COMPONENT MAY AD SOME MOUNTAIN CU TO THE SKIES
FRIDAY. LATE DAY HIGH CIRRUS MAY ARRIVE ACROSS LYH/DAN...FROM 15
TO 20 KFT.
EXTENDED AVIATION DISCUSSION...
THE WEATHER PICTURE FOR THIS WEEKEND AND THE EARLY PART OF NEXT
WEEK IS COMING A LITTLE INTO BETTER FOCUS AS THE WEATHER FORECAST
MODELS GRADUALLY RESOLVE THEIR DIFFERENCES CONCERNING THE TRACK
AND IMPACTS OF HURRICANE SANDY. SHOWER ACTIVITY...WITH A DECENT
POTENTIAL FOR MVFR/IFR CONDITIONS...IS EXPECTED TO PERSIST ACROSS
THE MOUNTAINS FROM SUNDAY THROUGH AT LEAST TUESDAY AS SANDY
CONTINUES TO MOVE NORTH ALONG THE COAST. AS OF THURSDAY
AFTERNOON...THE NHC PROJECTED PATH OF THE STORM CALLS FOR LANDFALL
TO OCCUR ANYWHERE FROM THE OUTER BANKS TO CAPE COD...WITH THE
LIKELIEST PATH TAKING THE STORM INTO NEW JERSEY. AS THE STORM
PASSES NORTHWARD ALONG THE COAST...EXPECT TO SEE WINDS BECOME
STRONG...POSSIBLY WITH +40KT GUSTS IN THE MOUNTAINS...FROM THE
NORTHWEST AS THE FORECAST AREA BECOMES PINCHED BETWEEN SANDY AND A
HIGH PRESSURE SYSTEM BUILDING IN FROM THE WEST. THERE ALSO IS THE
POSSIBILITY OF GUSTY WINDS AND SNOW SHOWERS GREATLY REDUCING VIS
AND/OR CIG IN THE LWB/BLF CORRIDOR...ESPECIALLY ON TUESDAY. BECAUSE
SANDY IS SUCH A BROAD STORM...THESE GUSTY WINDS WILL LIKELY
PERSIST INTO TUESDAY BEFORE DIMINISHING. HOW STRONG THE WINDS
BECOME DEPENDS ON THE INTENSITY AND TRACK OF SANDY...WHICH REMAINS
UNCERTAIN.
&&
.FIRE WEATHER...
FIRE WEATHER CONDITIONS REMAIN A CONCERN AS WE APPROACH THE
WEEKEND. MANY PARTS OF THE CWA HAVE NOT EXPERIENCED MEANINGFUL
RAIN SINCE EARLY OCTOBER. 10-HR FUEL MOISTURES ARE DROPPING INTO
THE 8-10 PERCENT RANGE AT SEVERAL RAWS SITES DURING RECENT
AFTERNOONS. ALTHOUGH WE CURRENTLY DO NOT HAVE THE WIND OR RH
CRITERIA IN ANY STATE...CONDITIONS COULD CHANGE THIS WEEKEND AS A
TIGHT PRESSURE GRADIENT DEVELOPS BETWEEN THE HIGH PRESSURE
BUILDING SEWD FROM THE MIDWEST AND HURRICANE SANDY OFF THE EAST
COAST. SUBSIDENCE ON THE WEST SIDE OF THE HURRICANE AND
DOWNSLOPE...DRYING NW FLOW WILL COMBINE TO RESULT IN LOWERING RH
VALUES. WHAT MAY SAVE THE AREA FROM CRITICAL RH VALUES WILL BE
CLOUD COVER AND MUCH COOLER TEMPERATURES. FIRE DANGER OR RED FLAG
CRITERIA REMAINS A POSSIBILITY FOR THE WEEKEND.
&&
.CLIMATE...
RECORD HIGH TEMPERATURES WERE SET AT BLUEFIELD AND DANVILLE ON
THURSDAY.
RECORD HIGHS FOR FRIDAY...
| OCT 26TH |
BLACKSBURG VA.|75 IN 2004|
BLUEFIELD WV..|78 IN 2010|
DANVILLE VA...|81 IN 1989|
LYNCHBURG VA..|85 IN 1919|
ROANOKE VA....|86 IN 1939|
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/NF
NEAR TERM...JH/NF
SHORT TERM...DS
LONG TERM...DS/JH
AVIATION...RAB/KM/NF
FIRE WEATHER...
CLIMATE...
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
301 AM CDT FRI OCT 26 2012
.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
301 AM CDT FRI OCT 26 2012
MAIN FORECAST CONCERNS ARE ON SKY COVER TODAY AND TEMPERATURES
THROUGHOUT.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING OVER THE EASTERN PACIFIC...TROUGHING OVER THE WESTERN
TWO THIRDS OF CANADA SOUTHWARD INTO THE CENTRAL PLAINS...RIDGING
ALONG THE EAST COAST INTO QUEBEC AND HURRICANE SANDY IN THE
NORTHWEST BAHAMAS. THE FORECAST AREA RESIDES IN THE WAKE OF A STRUNG
OUT SHORTWAVE FROM IOWA INTO EASTERN LAKE SUPERIOR...PROVIDING FOR
SUBSIDENCE AND DRYING ALOFT SEEN ON 00Z SOUNDINGS FROM MPX...ABR AND
BIS. THESE SAME SOUNDINGS SHOW A COLD FRONTAL/SUBSIDENCE INVERSION
AROUND 800MB WITH ABOUT A 50-75MB LAYER OF NEAR SATURATION BELOW IT.
THIS SATURATION WAS REFLECTED BY THE LARGE AMOUNT OF STRATUS
ENCOMPASSING THE NORTHERN PLAINS INTO THE UPPER MISSISSIPPI RIVER
VALLEY REGION LAST EVENING. HOWEVER...DURING THE LAST TWO HOURS A
LARGE AREA OF CLEARING HAS DEVELOPED ACROSS THE FORECAST AREA.
850MB TEMPS HAVE DROPPED CONSIDERABLY WITH THE 00Z MPX SOUNDING
REPORTING -7C...COMPARED TO 2C AT 12Z AND 9C 24 HOURS EARLIER. THIS
COLD AIR HAS BEEN RUSHING IN ON A STILL BREEZY NORTHWEST WIND...
CAUSED BY A TIGHT PRESSURE GRADIENT BETWEEN HIGH PRESSURE IN WESTERN
NEBRASKA AND LOW PRESSURE IN HUDSON BAY. THE WIND HAS KEPT
TEMPERATURES FROM TANKING WITH READINGS MAINLY IN THE 30S.
TODAY THROUGH SATURDAY...26.00Z MODEL GUIDANCE IS IN VERY GOOD
AGREEMENT THAT THE UPPER TROUGH AND ITS AXIS THROUGH THE CENTRAL
PLAINS STAYS NEARLY STATIONARY OR JUST SLOWLY SHIFTS EAST. THIS IS
MOSTLY DUE TO THE BLOCKING AHEAD OF IT...PRODUCED BY THE HIGHLY
AMPLIFIED RIDGING BUILDING UP THROUGH THE CANADIAN MARITIMES AND
HURRICANE SANDY PARALLELING THE SOUTHEAST U.S. COASTLINE. WITH
LITTLE MOVEMENT IN THE UPPER TROUGH...IT WILL BE VERY TOUGH TO GET
ANY PRECIPITATION PRODUCTION...OR WARM ADVECTION FOR THAT MATTER.
HOWEVER...THE HIGH PRESSURE AREA IN NEBRASKA IS PROGGED TO SHIFT
NORTHEAST INTO THE FORECAST AREA FOR LATE TONIGHT AND SATURDAY...
WHICH WILL ALLOW WINDS TO GRADUALLY DIMINISH. BIGGEST ISSUE IS SKY
COVER. WITH THE RECENT CLEARING THAT HAS OCCURRED...WENT WITH A MORE
OPTIMISTIC SCENARIO THAN WHAT THE PAST FEW RUNS OF THE RAP HAVE
SUGGESTED. IDEA HERE IS NOW THAT THE COMBINATION OF DIURNAL
HEATING...LINGERING SURFACE MOISTURE AND COOL AIR ALOFT SHOULD ALLOW
FOR SOME STRATOCUMULUS TO REDEVELOP. DIURNAL COOLING TONIGHT AND THE
HIGH PRESSURE AREA BUILDING IN WILL RESULT IN CLEARING SKIES. A GOOD
AMOUNT OF CIRRUS IS PROGGED TO ADVECT IN FROM THE NORTHWEST ON
SATURDAY...AHEAD OF A SHORTWAVE DROPPING INTO THE TROUGH OVER
NEBRASKA. WITH 850MB TEMPS OF -4 TO -8C BOTH TODAY AND
SATURDAY...TEMPERATURES WILL STRUGGLE TO GET MUCH ABOVE THE LOW TO
MID 40S. THE CLEARING SKIES TONIGHT AND THE COOL AIR IN PLACE SHOULD
EASILY ALLOW TEMPERATURES TO FALL INTO THE 20S...WHILE THE TYPICAL
COLD SPOTS COULD EVEN DROP INTO THE UPPER TEENS.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...THE SHORTWAVE MENTIONED ON
SATURDAY DROPPING INTO NEBRASKA WILL BE A NOTABLE FEATURE...
ESPECIALLY FOR BEING ABLE TO PICK UP SANDY AND HELP CURVE IT BACK
TOWARDS THE MID-ATLANTIC/NORTHEAST EARLY NEXT WEEK. FOR US...THE
SHORTWAVE DIGS DOWN INTO THE TENNESSEE VALLEY BY SUNDAY. ANY
PRECIPITATION ASSOCIATED WITH THIS SHORTWAVE LOOKS TO STAY SOUTH AND
WEST OF THE AREA...WHILE THE HIGH PRESSURE AREA REMAINS NEARLY
STATIONARY. THIS HOLDS TRUE RIGHT THROUGH SUNDAY NIGHT. WITH UPPER
TROUGHING AND HIGH PRESSURE STILL IN PLACE...850MB TEMPS ARE GOING
TO STRUGGLE TO CLIMB...WITH MAYBE A 1-2C RISE OFF OF SATURDAY.
THUS...ANTICIPATING SUNDAYS HIGHS TO BE SIMILAR TO SATURDAY...IN
THE LOW TO MID 40S. SOME CIRRUS AND PERHAPS EVEN MID CLOUD COVER ON
SATURDAY NIGHT SHOULD RESULT IN A SLIGHTLY WARMER NIGHT COMPARED TO
TONIGHT. SAME HOLDS TRUE FOR SUNDAY NIGHT WITH YET ANOTHER AREA OF
CIRRUS PROGGED TO DROP IN FROM THE NORTHWEST.
.LONG TERM...MONDAY THROUGH THURSDAY NIGHT
301 AM CDT FRI OCT 26 2012
26.00Z ECMWF/GFS/CANADIAN/UKMET AND GFS ENSEMBLES ARE ALL IN GOOD
AGREEMENT OF SHOWING A BLOCKED UP UPPER LEVEL PATTERN ACROSS NORTH
AMERICA NEXT WEEK. A LOT OF THIS BLOCKING IS DUE TO SUBTROPICAL
RIDGING STUCK OVER NEWFOUNDLAND...ALLOWING HURRICANE SANDY TO
PHASE WITH THE CURRENT UPPER TROUGH OVER THE CENTRAL PLAINS.
ALTHOUGH THERE ARE CERTAINLY PLENTY OF DETAIL DIFFERENCES ABOUT
THE POST-TROPICAL STATE AND TRACK OF HURRICANE SANDY...OUR AREA
STAYS ON THE WEST/SUBSIDENT SIDE OF THE PHASED SYSTEM. THIS SHOULD
MAINTAIN A RIDGE OF HIGH PRESSURE AT THE SURFACE NEAR OR JUST WEST
OF THE AREA...ALONG WITH DRY WEATHER. NOTE THAT THE 26.00Z ECMWF
DOES SHOW A LITTLE MORE WESTWARD TRACK OF POST-TROPICAL SANDY...
WHICH RESULTS IN A BREEZY TUESDAY AND TUESDAY NIGHT PERIOD. THE
MODEL IS EVEN SUGGESTING THE DEFORMATION BAND COULD GET CLOSE TO
CENTRAL WISCONSIN ON WEDNESDAY. THERE ARE HINTS TOWARDS THURSDAY
NIGHT OF UPPER RIDGING BUILDING OVER THE WESTERN U.S. GETTING
PUSHED EAST TOWARDS THE AREA...THOUGH PLENTY OF UNCERTAINTY EXISTS
ON THIS GIVEN THE ISSUES WITH THE EJECTION OF POST-TROPICAL SANDY.
850MB TEMPS WILL SLOWLY WARM THROUGH NEXT WEEK...WITH MOST AREAS
SEEING READINGS OF 0C OR HIGHER BY WEDNESDAY. THUS...ANTICIPATE A
GENERAL WARMING TREND. FOLLOWED A CONSENSUS SOLUTION FOR
TEMPERATURES.
&&
.AVIATION...THROUGH 06Z SATURDAY
1108 PM CDT THU OCT 25 2012
THE MAIN FOCUS OVERNIGHT INTO FRIDAY IS WITH CLOUD COVER AND HOW
PREVALENT IT WILL BE. MUCH OF THE MVFR CEILINGS HAVE GONE TO THE
SOUTHEAST OF RST/LSE WITH THE CLOUD COVER ACROSS
MINNESOTA/NORTHWEST WISCONSIN IN THE 4-5KFT RANGE. WITH DRIER AIR
TRYING TO MOVE IN AND NORTHWESTERLY LOW TO MID LEVEL FLOW...WOULD
EXPECT CONDITIONS TO STAY VFR THROUGH THE PERIOD. WINDS WILL
REMAIN OUT OF THE NORTHWEST AND SHOULD CONTINUE TO BE GUSTY
OVERNIGHT ON INTO FRIDAY THOUGH GRADUALLY DIMINISHING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
301 AM CDT FRI OCT 26 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1039 AM EDT FRI OCT 26 2012
.UPDATE...
BAND OF SHOWERS CONTINUES TO SHIFT EASTWARD ACROSS NW OHIO
COUNTIES THIS MORNING IN ASSOCIATION WITH LOW LEVEL FRONTAL ZONE
AND A WEAK SHORT WAVE LIFTING NORTHEAST OUT OF SOUTHEAST INDIANA.
LAGGING 800:700 HPA FRONTAL ZONE WILL BE VERY SLOW TO TRACK
ACROSS SOUTHEAST PORTIONS OF THE AREA THIS AFTERNOON. IN
ADDITION...WATER VAPOR IMAGERY SHOWING A FAIRLY PRONOUNCED
UPSTREAM TROUGH ACROSS THE CENTRAL PLAINS WITH 14Z RAP INITIALIZING
A SHEARED VORTICITY MAXIMUM FROM NORTHERN MISSOURI INTO NORTHWEST
ILLINOIS PRECEDING THIS SHORT WAVE. AS MID/UPPER LEVEL TROUGH AXIS
ACROSS THE PLAINS SHIFTS EASTWARD TODAY...WOULD SUSPECT THAT
RENEWED LIGHT SHOWER DEVELOPMENT WILL BE POSSIBLE ALONG LAGGING
MID LEVEL BAROCLINC ZONE ACROSS PRIMARILY SOUTHEAST PORTIONS OF
THE FORECAST AREA. HOWEVER...GIVEN TIMING OF AFOREMENTIONED MID
LEVEL FORCING...THIS ENHANCEMENT MAY NOT OCCUR UNTIL THE EVENING.
STARTING TO SEE SOME LIGHT RETURNS BEHIND THE INITIAL RAIN BAND
ACROSS SOUTHERN ILLINOIS AND WILL NEED TO WATCH TRENDS NORTHEAST
AND HOW THIS FILLS IN ALONG THE MID LEVEL FRONT THIS AFTERNOON.
HAVE OPTED TO STAY CLOSE TO PREVIOUS FORECAST AND JUST SHAVE POPS
SLIGHTLY ACROSS THE WESTERN EXTENT WHERE LOW LEVEL MOISTURE
AVAILABILITY BECOMES MORE IN QUESTION. NO CHANGE TO OTHER FORECAST
ELEMENTS ALTHOUGH RAOB/TAMDAR DATA SUGGESTS LOW LEVEL INVERSION
MAY BE A BIT STRONGER THAN MODEL DEPICTION...AND THUS LOW CLOUDS
MAY LINGER A BIT LONGER. HOWEVER...MAGNITUDE OF DRY AIR ADVECTION
LATER TODAY SHOULD TEND TO OVERWHELM INFLUENCES OF LOW LEVEL
INVERSION ALLOWING FOR AT LEAST PARTIAL SUNSHINE ACROSS AT LEAST MOST
OF WESTERN PORTIONS OF THE AREA. UPDATE FORECAST SENT EARLIER THIS
MORNING TO REFRESH EARLY MORNING WORDING AND TO ACCOUNT FOR
MORNING POP TRENDS.
&&
.PREV DISCUSSION... /ISSUED 657 AM EDT FRI OCT 26 2012/
AVIATION.../12Z TAFS/
BACK EDGE OF POST FRONTAL MVFR STRATO CU DECK MOVG INTO NW
INDIANA SHOULD CLEAR SBN BY MIDDAY WITH VFR CONDITIONS THE
REMAINDER OF THE PERIOD. AT FWA... POST-FRONTAL BAND OF SHOWERS IS
EXPECTED TO MOVE EAST OF THE TERMINAL AROUND MIDDAY WITH
CONDITIONS BECOMING VFR THIS AFTN... CONTG TONIGHT. NW SFC WINDS
12-18KT AT BOTH TERMINALS TODAY... VEERING NORTH AROUND 10KT
TONIGHT AS RIDGE BUILDS EAST FROM THE CENTRAL PLAINS INTO THE WRN
GRTLKS.
PREV DISCUSSION... /ISSUED 342 AM EDT FRI OCT 26 2012/
SHORT TERM...TODAY THROUGH SATURDAY NIGHT
STRONG SFC COLD FRONT WILL CLEAR OUR NW OH COUNTIES BY DAYBREAK WITH
TEMPS IN THE MID/UPPER 60S QUICKLY FALLING INTO THE 50S/40S.
TEMPS HAVE ALREADY DROPPED INTO THE 40S ACROSS OUR WESTERN ZONES
WITH LITTLE RECOVERY ANTICIPATED TODAY IN STRONG CAA REGIME...WITH
HIGHS NEARLY 30F COOLER THAN YESTERDAY. POST FRONTAL BAND OF RAIN
SHOWERS ORIENTED NW TO SW (NEARLY 50 MILES WIDE) WILL SLIDE EAST
THROUGH THE AREA TODAY...WITH OUR NW INDIANA AND SW LOWER MI
COUNTIES LIKELY SEEING A MAINLY DRY DAY AS RAIN BAND EXITS EAST
AROUND OR JUST AFTER DAYBREAK. THIS BAND OF RAIN IS SET UP IN
TYPICAL ANAFRONT FASHION, GETTING A BOOST FROM A WESTERN/NORTHERN
GREAT LAKES ~120 KT UPPER LEVEL JET IN ADVANCE OF A CENTRAL CONUS
UPPER TROUGH. THERE MAY BE A LULL IN SHOWER INTENSITY/COVERAGE FOR A
PERIOD TODAY AS THE FRONTAL SCALE CIRCULATION WEAKENS. THIS LULL WILL
BE BRIEF AS A MID LVL SHORTWAVE OVER THE CENTRAL HIGH PLAINS/ROCKIES
EJECTS NE INTO THE GREAT LAKES/OH VALLEY LATER TODAY INTO TONIGHT.
THE RESULTING MID LVL FRONTOGENETIC RESPONSE WILL LIKELY AID IN AN
INCREASE IN SHOWER COVERAGE DURING THIS TIME. HOWEVER...DRIER AIR
WILL HAVE WORKED INTO MOST OF OUR IN/MI COUNTIES BY THIS TIME WITH
THE BEST CHANCE FOR RAINFALL ALONG THE STALLING BAROCLINIC ZONE
ACROSS OUR FAR SOUTHEAST INTO CENTRAL OHIO (BEST CHANCES JAY COUNTY
INDIANA NE INTO VAN WERT/PUTNAM/ALLEN COUNTIES IN OHIO). RAINFALL
AMOUNTS GREATER THAN A HALF AN INCH WILL BE POSSIBLE HERE WITH
LIGHTER AMOUNTS CLOSER TO A QUARTER OF AN INCH ELSEWHERE.
OTHERWISE...COOL/DRY NORTHERLY FLOW IS STILL EXPECTED SATURDAY INTO
SATURDAY NIGHT WITH ONLY MINOR TWEAKS MADE.
LONG TERM.../SUN-THU/
GFS CONTS TO INDICATE TRACK OF HURRICANE SANDY WILL BE TO THE
RIGHT/EAST OF ECMWF`S FCST. ECMWF HAS BEEN MOST CONSISTENT OF THE
MEDIUM RANGE MODELS BUT CONSIDERABLE VARIABILITY ON TRACK CONTS FROM
RUN-RUN... ESPECIALLY FROM GFS/GEM. FOR SUN/SUN NGT LEANED TOWARD A
00Z GFS/12Z ECMWF COMPROMISE FOR FCST DETAILS AS NAM WAS AN OUTLIER
INDICATING MUCH FASTER NORTHERLY MOVEMENT OF THE WRN ATLANTIC
HURRICANE WHILE GEM WAS A FAR RIGHT TRACK OUTLIER. THUS... UPR LEVEL
TROF EXPECTED TO MOVE ACROSS THE GRTLKS SUN/SUN NGT WITH SFC RIDGE
OVER THE UPR MS VALLEY REMAINING NEARLY STNRY AS HURRICANE SANDY
MOVES NORTHWARD OFF THE EAST COAST. THIS SCENARIO SHOULD RESULT IN
DRY WX WITH BLO NORMAL TEMPS AND MODEST NORTHERLY GRADIENT FLOW
ACROSS OUR AREA FOR THE END OF THE WEEKEND.
SANDY IS EXPECTED TO CURVE NWWD MONDAY AND MOVE INLAND OVER THE
MID-ATLANTIC STATES TUE... WITH EXTRA-TROPICAL LOW THEN SLOWLY
CURVING BACK NE INTO SRN QUEBEC BY THU EVE. GIVEN THIS TRACK...
STILL APPEARS AS IF WRN EDGE OF PRECIP SHIELD ASSOCIATED WITH THIS
LOW WILL BE OVER OR JUST EAST OF OUR CWA. ALSO CONTS TO BE A CHC FOR
SOME LAKE EFFECT SHOWERS NEAR LAKE MICHIGAN MID-WEEK WITH NNW LOW
LEVEL FLOW AND DELTA T`S IN THE TEENS. THUS POPS GENERALLY RAMPED UP
A NOTCH THROUGH THIS PERIOD. TEMP PROFILES CONTG TO SUGGEST IT
COULD BE COLD ENOUGH AT TIMES FOR THE PRECIP IF IT OCCURS TO FALL AS
SNOW... MAINLY DURING THE OVERNIGHT HOURS.
HIGH TEMPS EXPECTED TO RANGE FROM 45-50 SUNDAY... GRDLY LOWERING TO
THE M40S ACROSS THE AREA BY TUE-WED WHICH SHOULD BE THE CLOUDIEST
DAYS OF THE PERIOD... AND THEN SLOWLY MODERATING BACK TO NEAR 50 BY
THU AS THE LOW PULLS AWAY. LOWS EXPECTED TO BE IN THE L-M30S THROUGH
THE PERIOD.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 5 AM EDT SUNDAY FOR LMZ043-046.
&&
$$
SHORT TERM...STEINWEDEL
LONG TERM...JT
AVIATION...JT
UPDATE...MARSILI
AREA FORECAST DISCUSSION
NWS TOPEKA KS
639 AM CDT FRI OCT 26 2012
...UPDATE TO AVIATION...
.DISCUSSION...
SHORTWAVE TROUGH WAS LOCATED OVER COLORADO AND THE NEBRASKA
PANHANDLE WITHIN A BROADER TROUGH MOVING INTO THE CENTRAL STATES.
COLD HIGH PRESSURE WAS CENTERED OVER NORTH CENTRAL NEBRASKA THIS
MORNING. LOW CLOUD DECK WAS DISSIPATING OVER NORTHEAST KANSAS WITH
MOST AREAS NORTH OF INTERSTATE 70 CLEAR. OUT WEST HIGH AND MID
LEVEL CLOUDS WERE SPILLING INTO NORTH CENTRAL KANSAS AS WELL.
TEMPERATURES WILL START OFF NEAR FREEZING THEN WARM ONLY INTO THE
MID AND UPPER 40S TODAY.
TONIGHT SKIES WILL CLEAR OUT AS THE SHORTWAVE TROUGH EXITS THE AREA
AND HIGH PRESSURE RIDGE SETTLES OVER THE NORTHEAST KANSAS. WITH THE
LIGHT WINDS AND CLEAR SKIES EXPECT GOOD RADIATIONAL COOLING WITH
TEMPS FALLING INTO THE LOW TO MID 20S.
THE COLD TEMPERATURES WILL CONTINUE THROUGH SUNDAY WITH NORTHWEST
FLOW ALOFT AND THE SURFACE HIGH PRESSURE RIDGE REMAINING IN THE
AREA. LOWS IN THE MID AND UPPER 20S SUNDAY MORNING WITH HIGHS IN THE
LOWER 50S.
FOR MONDAY THROUGH THURSDAY...A GRADUAL WARM UP IS EXPECTED AS
HEIGHTS RISE OVER THE CENTRAL PLAINS AND ROCKIES. TEMPERATURES WILL
RANGE FROM THE MID AND UPPER 50S FOR MONDAYS HIGHS TO THE UPPER 50S
TO LOWER 60S TUESDAY THROUGH THURSDAY. LOWS WILL RANGE FROM THE 30S
MONDAY TO THE UPPER 30S TO LOWER 40S FOR THE REST OF THE PERIOD.
53
&&
.AVIATION...
VFR CONDITIONS EXPECTED. STRATUS JUST ABOVE MVFR LINGERS IN THE
TOP/FOE AREA THIS MORNING AND MODELS HAVE BEEN STRUGGLING TO KEEP
UP WITH THE STRATUS OVERNIGHT. LATEST RAP AND HRRR RUNS...WHICH
HAVE BEEN DOING THE BEST...KEEP LIMITING CLOUDS OUT AND WILL
CAUTIOUSLY GO THIS ROUTE.
65
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
514 AM MDT FRI OCT 26 2012
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 236 AM MDT FRI OCT 26 2012
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOW LARGE SCALE TROUGH ACROSS
THE NORTHERN PLAINS WITH A SHORTWAVE TROUGH OVER CENTRAL COLORADO.
RADAR COMPOSITE SHOWS LIGHT SNOW EXTENDING ACROSS EASTERN COLORADO
JUST ENTERING THE FAR WESTERN EXTENT OF OUR CWA. THIS HAS FORMED
ALONG AN AXIS OF H7 FRONTOGENESIS AHEAD OF H7 TROUGH AXIS. AS MEAN
H5/H7 TROUGH SHIFTS EAST LIGHT SNOW SHOULD CONTINUE TO SPREAD EAST
TOWARDS THE CO/KS STATE LINE. BEST FORCING/MID LEVEL MOISTURE SHOULD
REMAIN OVER THE WESTERN CWA. LATEST SHORT RANGE GUIDANCE GENERALLY
KEEPS LIGHT SNOW OVER OUR EASTERN COLORADO COUNTIES AND FAR WESTERN
KS THROUGH 15Z...WITH SUBSIDENCE AND ISENTROPIC DOWNGLIDE
OVERSPREADING THE CWA PUTTING AN END TO PRECIP CHANCES BY MIDDAY.
WE WILL CONTINUE TO SEE BELOW NORMAL TEMPERATURES TODAY AND TONIGHT
WITH THE SAME COLD AIR MASS STILL IN PLACE. HIGHS TODAY WILL BE
SIMILAR TO FRIDAY WITH AFTERNOON TEMPS IN THE UPPER 30S ACROSS THE
WEST AND MID 40S ACROSS THE EAST. CLOUD COVER COULD LIMIT
RADIATIONAL COOLING TONIGHT...HOWEVER WITH THE COLD AIR MASS STILL
IN PLACE LOWS SHOULD STILL DROP TO THE MID TO UPPER 20S FOR MOST
LOCATIONS...AND NEAR 20F WHERE CLOUDS CLEAR OUT.
NW FLOW DEVELOPS OVER THE CWA FRIDAY AS H5 RIDGE BUILDS OVER THE
WESTERN US AND BEGINS TO SHIFT TOWARDS THE CENTRAL ROCKIES THROUGH
THE WEEKEND. GFS HAS INDICATED A WEAK SHORTWAVE TROUGH WILL MOVE
JUST NORTH OF THE CWA IN NEBRASKA SATURDAY. MOST GUIDANCE
GENERALLY INDICATES STORM TRACK SHOULD REMAIN NORTH OF OUR
CWA...SO I KEPT DRY FORECAST IN PLACE. AIR MASS OVER THE CWA
SHOULD SLOWLY MODERATE WITH HIGHS IN THE LOW 50S SATURDAY...AND
UPPER 50S ON SUNDAY.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 236 AM MDT FRI OCT 26 2012
DRY CONDITIONS WILL CONTINUE THROUGH MOST OF NEXT WEEK AS THE UPPER
LEVEL RIDGE REMAINS OVER THE WESTERN HALF OF THE CONUS. MID WEEK AN
UPPER LEVEL TROUGH MOVES ONSHORE OVER THE PACIFIC NORTHWEST...MOVING
INTO THE CENTRAL PLAINS BY THE START OF THE WEEKEND. THE GEFS
MEMBERS DISAGREE WITH THE TRACK OF THE TROUGH...WITH MOST MEMBERS
KEEPING IT NORTH OF THE AREA. TEMPERATURES THROUGH THURSDAY WILL BE
NORMAL...WITH BELOW NORMAL TEMPERATURES IN STORE AS A COLD FRONT
MOVES THROUGH FRIDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 513 AM MDT FRI OCT 26 2012
LOW STRATUS HAS MOVE OVER BOTH TERMINALS EARLY THIS MORNING. MVFR
CIGS AT KMCK ARE ASSOCIATED WITH STRATUS FIELD OVER CENTRAL KS/NE
SPREADING DRIFTING WEST...WHICH SHOULD IMPROVE TO VFR BY 15Z. IFR
CIGS HAVE DEVELOPED OVER KGLD WITH AREA OF LIGHT SNOW ACROSS
EASTERN COLORADO JUST NOW BEGINNING TO APPROACH THE TERMINAL FROM
THE WEST. IFR VIS/CIGS AND LIGHT SNOW WILL CONTINUE TO BE POSSIBLE
AT KGLD THROUGH 16Z AS THE PARENT SYSTEM SHIFTS EAST THROUGH MID
MORNING. CONDITIONS SHOULD RAPIDLY IMPROVE AFTER 16Z WITH A
DRY/STABLE AIR MASS MOVING BACK OVER KGLD. BASED ON LATEST SHORT
RANGE GUIDANCE IT APPEARS SNOW SHOULD STAY WEST OF KMCK...SO NO
MENTION INCLUDED. WILL NEED TO MONITOR TRENDS. AFTER CONDITIONS
IMPROVE THIS MORNING VFR SHOULD PREVAIL THROUGH THE REMAINING TAF
PERIOD ALONG WITH LIGHT WINDS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JTL
AVIATION...DR
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1049 AM EDT FRI OCT 26 2012
.Forecast Update...
Updated at 1045 AM EDT Fri Oct 26 2012
Front has pushed well into the Bluegrass already this morning. Rain
lagging well behind as it has yet to cross I-65. Did a quick update
to the forecast to better break down precip timing, as well as to
clip a few degrees off max temps in the Bluegrass. Still a bit
concerned that those high temps in the Bluegrass will need to be
trimmed back even further, but there is still a window for a little
bit of warming before precip arrives.
&&
.Short Term (Today through Saturday)...
Issued at 326 AM EDT Fri Oct 26 2012
...Sharp cold front moving through the region today will result in
falling temperatures...
Well advertised potent upper level trough and associated surface
cold front are heading through the region early this morning. The
models have been playing catch up with respect to the timing and the
latest HRRR and RAP guidance seems to have a good handle on things.
Based on WSR-88D velocity moments, the front is just west of a
KSDF-KFTK-KBWG line. The front should cross the I-65 corridor
within the next hour and then head toward the I-75 corridor towards
sunrise. A brief period of breezy, perhaps gusty winds will
accompany the front as it pushes through with winds shifting from
the south to the northwest. Precipitation is lagging behind the
front by a few hours, so in the near term, dry conditions are
expected. Based on upstream observations, we`re seeing a 12-15
degree drop behind the front, so while temperatures in the central
sections are still in the mid-upper 60s, those reading will fall
quickly over the next couple of hours.
For today, the frontal boundary is forecast to push eastward through
the day. Some pre-frontal warming may occur in the east just ahead
of the front, but temperatures by and large will fall throughout the
day. All of the deterministic and ensemble guidance continues to
show that post-frontal precipitation is very likely, so we have
bumped up the clouds and precipitation chances a bit for today.
Highest PoPs today will be in the west and central sections with
higher PoPs in the east holding off until later this afternoon and
evening. As for temperatures, highs today will range from the upper
40s to the lower 50s in the west and central sections. Upper 50s to
the lower 60s are likely in the east, but these will occur early as
temperatures fall into the upper 40s to lower 50s by evening.
For tonight, the aforementioned frontal boundary will continue to
surge eastward. Lagging post-frontal precipitation band will likely
continue to slowly move eastward through the forecast area. It
appears that a weak upper level wave will pass overhead tonight,
which may enhance our PoP chances for the evening and early
overnight hours. Will keep chance PoPs in for the far
west/northwest sections with likely PoPs in the central and eastern
sections. Overall, best chances of rain tonight look to be over our
eastern forecast area. Precipitation should generally be exiting
the forecast area by dawn and drier air will attempt to punch into
our west/northwest sections late. With this drier air coming in,
we`re likely to see some partial clearing toward sunrise which will
allow for a gradient of temperatures across the area. Overnight
lows should range from the upper 30s in the far west/northwest with
lower 40s in the central and lower-mid 40s in the east.
For Saturday, high pressure to the west will continue to slowly
build into the region. This will result in clearing working across
the forecast area from west to east. Typically the models are too
fast at clearing things out. In addition, cold air advection aloft
will likely result in a stratocumulus deck building in. Partly
cloudy conditions look reasonable for areas west of I-65 with mostly
cloudy conditions east of I-65...though skies will likely become
mostly clear by evening. As for temperatures, highs will be in the
upper 40s to around 50 in the east/northeast with lower-middle 50s
across the central and western sections.
.Long Term (Saturday Night through Thursday)
Issued at 305 AM EDT Fri Oct 26 2012
Across the country, the big weather story early next week will
concern the mid-Atlantic and our northeastern states. Hurricane
Sandy, now a category one hurricane east of Florida is increasingly
likely to begin developing into into an intense extra-tropical
cyclone by Sunday well east of North Carolina. The majority of the
most recent guidance shows a deep 500mb trough forming over the
Appalachians. Should this occur, this cyclone would be pulled
northwest towards New York or southern New England by late Monday
with an exceptionally deep surface low and gale force winds.
The unusual track of this storm is a result of strong blocking
across the entire Atlantic basin. Upstream from this, across the
Lower Ohio Valley and midwest, northerly flow already in place
Sunday will simply not budge, continuing through at least Thursday.
A lengthy period of cool weather is practically certain for the
Commonwealth and southern Indiana. Clearing is forecast to have
taken place across southern Illinois and western Kentucky by late
Saturday. However, cloud cover is likely to linger across eastern
Kentucky into Sunday morning. Across central Kentucky, cloud cover
will remain a tricky forecast through Sunday as the NAM and the GFS
have contrasting forecasts on how quickly clouds erode over eastern
Kentucky.
At the surface, a ridge of high pressure extending southward along
the Mississippi River on Sunday simply will not budge. Northerly
surface winds are likely for our region for all of the early portion
of next week as the afore-mentioned deep nor`easter creeps slowly
over southern New England.
Temperatures will remain pretty consistent Sunday through Wednesday
in this basically blocky weather pattern. Expect highs in the lower
to mid 50 each day, with Monday potentially a bit cooler. Lows will
bottom out in the lower to mid-30s.
Expect clear to partly cloudy skies Monday through Thursday. It is
possible that overcast skies associated with the western edge of the
New England storm may push as far west as central Kentucky late
Monday or Tuesday if some of more western model solutions verify.
&&
.Aviation (12Z TAF Issuance)...
Issued at 645 AM EDT Fri Oct 26 2012
Surface cold front continues to make steady progress eastward this
morning. The front has slowed down a bit and is located along a
line from near KCVG-KFFT to just east of KBWG. Surface winds are
picking up slightly ahead of the front out of the southwest, but
will quickly veer around to the northwest after frontal passage.
Ceilings have fallen into the MVFR category behind the front and
they will likely remain there for the remainder of the day.
Radar returns show a batch of post frontal showers moving into
western Kentucky and southwest Indiana. These showers will head
east and start to impact KSDF/KBWG by 26/14-15Z and eventually get
over into the KLEX terminal later this afternoon. MVFR visibilities
and ceilings are expected to prevail this afternoon and into this
evening. The latest data does suggest that ceilings may eventually
fall into the high end of the IFR range tonight. Surface winds will
remain out of the northwest at 10-14kts with occasional gusts up to
18-20kts at times. The gusts will level off tonight and winds are
expected to become more northerly.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........RAS
Short Term.......MJ
Long Term........JSD
Aviation.........MJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
937 AM EDT FRI OCT 26 2012
.UPDATE...
ISSUED AT 937 AM EDT FRI OCT 26 2012
BASED ON CURRENT RADAR TRENDS AND HRRR FORECAST IT APPEARS SHOWERS
SHOULD HOLD OFF UNTIL LATE AFTERNOON OR EVENING. THIS IS WELL HANDLED
IN CURRENT NDFD. MADE ONLY MINOR GRID CHANGES BASED ON CURRENT
OBSERVATIONS WITH NO CHANGES TO PRECIPITATION TIMING.
UPDATE ISSUED AT 805 AM EDT FRI OCT 26 2012
ONLY MINOR GRID CHANGES WERE NEEDED BASED ON LATEST OBSERVATIONS...
WITH NO SIGNIFICANT IMPACT ON THE FORECAST
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 400 AM EDT FRI OCT 26 2012
THERE IS GOOD MODEL AGREEMENT DURING THE PERIOD. A COLD FRONT
STRETCHED FROM WESTERN OH THROUGH WESTERN KY DURING THE PREDAWN
HOURS...AND IT WILL MOVE SE THROUGH OUR FORECAST AREA TODAY.
CONVECTION AHEAD OF THE FRONT SHOULD REMAIN CAPPED AROUND 10K FEET
TODAY...WITH CLOUD TOP TEMPS REMAINING TO WARM FOR ICE
FORMATION...AND HENCE LIMITING PRECIP POTENTIAL. HOWEVER...CLOUD
DEPTH SHOULD BE ENOUGH FOR SOME LIGHT SHOWERS...AND WILL USE 20-30
PERCENT POPS. THE BEST SHOT AT PRECIP WILL COME TONIGHT INTO SATURDAY
AS WARM AIR ADVECTION BRINGS ISENTROPIC LIFT ABOVE THE FRONTAL
INVERSION AND IS AIDED BY LIFT IN THE RIGHT ENTRANCE REGION OF AN
UPPER JET. DEEP MOISTURE WILL BE LOST LATER ON SATURDAY AND SATURDAY
NIGHT...WITH PRECIP BECOMING LIGHTER AND MORE SPARSE. IN
ADDITION...MUCH COOLER AIR MOVING IN BEHIND THE FRONT WILL PUT AN END
TO OUR MILD WEATHER.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 330 AM EDT FRI OCT 26 2012
THE LONG TERM PERIOD WILL BE DOMINATED BY DEEP TROUGHING OVER THE
EASTERN U.S. AS STRONG BLOCKING OVER THE NORTHERN ATLANTIC KEEPS
EVERYTHING LOCKED IN PLACE. THE BIG QUESTION CONTINUES TO REVOLVE
AROUND HOW HURRICANE SANDY BEHAVES EARLY NEXT WEEK. AFTER SOME
RELATIVE AGREEMENT SHOWED UP IN THE 25/12Z PROGS REGARDING SANDY/S
LANDFALL AND SUBSEQUENT PATH...THE 26/00Z RUNS HAVE SPREAD BACK OUT
AGAIN. LANDFALL NOW RANGES FROM MAINE IN THE GEM...THE NEW YORK CITY
VICINITY IN THE GFS AND UKMET...TO THE DELMARVA IN THE ECMWF. THE
ECMWF CONTINUES TO OFFER THE MOST IMPACT FOR EAST KENTUCKY WITH
SEVERAL INCHES OF WET SNOW AND GUSTY WINDS IN THE CARDS SHOULD THAT
SOLUTION PAN OUT. HOWEVER...WITH SO MUCH TIME REMAINING BEFORE
LANDFALL...STILL AT LEAST 4 DAYS...AND SO MANY VARIABLES TO
CONSIDER...WE WILL CONTINUE TO SIDE WITH A STRICT MODEL BLEND
APPROACH FOR FORECAST DETAILS AND STAY AWAY FROM SIDING WITH ANY ONE
MODEL.
A COLD FRONT WILL BE STATIONARY JUST TO OUR EAST ON SUNDAY.
CONSIDERABLE CLOUD COVER AND A FEW SHOWERS WILL LINGER BEHIND THIS
FRONT INTO SUNDAY NIGHT. WE WILL THEN CONTINUE TO MENTION A LOW
CHANCE OF PRECIPITATION FROM MONDAY THROUGH WEDNESDAY NIGHT FOR MOST
AREAS FACTORING IN THE POSSIBILITY OF SOME IMPACT FROM SANDY. TEMPS
WILL SUPPORT A MENTION OF SNOW AS WELL...ESPECIALLY DURING THE
OVERNIGHT AND EARLY MORNING HOURS.
TEMPERATURES WILL REMAIN IN THE 40S FOR MOST LOCATIONS EACH DAY
THROUGH THE PERIOD. OVERNIGHT LOWS ARE EXPECTED TO FALL INTO THE
30S...AND SHOULD SANDY TAKE A MORE NORTHERN ROUTE INLAND AND HAVE
LESS IMPACT ON OUR WEATHER...THEN 20S WILL BE POSSIBLE NEXT WEEK.
RIGHT NOW...OUR FORECAST CONTAINS A LITTLE TOO MUCH CLOUD COVER AND
WIND EACH NIGHT TO FORECAST TEMPS MUCH BELOW 32 DEGREES FOR ANY ONE
PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 756 AM EDT FRI OCT 26 2012
A COLD FRONT WILL MOVE THROUGH FROM NW TO SE DURING THE DAY TODAY...
BUT VFR IS EXPECTED TO PERSIST INTO TONIGHT. WELL BEHIND THE FRONT A
LOW OVERCAST WILL MOVE IN...RESULTING IN WIDESPREAD MVFR CONDITIONS
DEVELOPING FROM NW TO SE ACROSS THE FORECAST AREA BETWEEN 23Z AND
06Z...WITH LOCALIZED IFR. SHOWERS ARE ALSO FORECAST TO ARRIVE IN
WESTERN LOCATIONS FROM SOMERSET TO MOREHEAD NEAR AROUND 06Z...AND
THEN SLOWLY SPREAD SOUTHEAST OVERNIGHT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...HAL
LONG TERM....ABE
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
647 AM EDT FRI OCT 26 2012
...Updated Aviation Discussion...
.Short Term (Today through Saturday)...
Issued at 326 AM EDT Fri Oct 26 2012
...Sharp cold front moving through the region today will result in
falling temperatures...
Well advertised potent upper level trough and associated surface
cold front are heading through the region early this morning. The
models have been playing catch up with respect to the timing and the
latest HRRR and RAP guidance seems to have a good handle on things.
Based on WSR-88D velocity moments, the front is just west of a
KSDF-KFTK-KBWG line. The front should cross the I-65 corridor
within the next hour and then head toward the I-75 corridor towards
sunrise. A brief period of breezy, perhaps gusty winds will
accompany the front as it pushes through with winds shifting from
the south to the northwest. Precipitation is lagging behind the
front by a few hours, so in the near term, dry conditions are
expected. Based on upstream observations, we`re seeing a 12-15
degree drop behind the front, so while temperatures in the central
sections are still in the mid-upper 60s, those reading will fall
quickly over the next couple of hours.
For today, the frontal boundary is forecast to push eastward through
the day. Some pre-frontal warming may occur in the east just ahead
of the front, but temperatures by and large will fall throughout the
day. All of the deterministic and ensemble guidance continues to
show that post-frontal precipitation is very likely, so we have
bumped up the clouds and precipitation chances a bit for today.
Highest PoPs today will be in the west and central sections with
higher PoPs in the east holding off until later this afternoon and
evening. As for temperatures, highs today will range from the upper
40s to the lower 50s in the west and central sections. Upper 50s to
the lower 60s are likely in the east, but these will occur early as
temperatures fall into the upper 40s to lower 50s by evening.
For tonight, the aforementioned frontal boundary will continue to
surge eastward. Lagging post-frontal precipitation band will likely
continue to slowly move eastward through the forecast area. It
appears that a weak upper level wave will pass overhead tonight,
which may enhance our PoP chances for the evening and early
overnight hours. Will keep chance PoPs in for the far
west/northwest sections with likely PoPs in the central and eastern
sections. Overall, best chances of rain tonight look to be over our
eastern forecast area. Precipitation should generally be exiting
the forecast area by dawn and drier air will attempt to punch into
our west/northwest sections late. With this drier air coming in,
we`re likely to see some partial clearing toward sunrise which will
allow for a gradient of temperatures across the area. Overnight
lows should range from the upper 30s in the far west/northwest with
lower 40s in the central and lower-mid 40s in the east.
For Saturday, high pressure to the west will continue to slowly
build into the region. This will result in clearing working across
the forecast area from west to east. Typically the models are too
fast at clearing things out. In addition, cold air advection aloft
will likely result in a stratocumulus deck building in. Partly
cloudy conditions look reasonable for areas west of I-65 with mostly
cloudy conditions east of I-65...though skies will likely become
mostly clear by evening. As for temperatures, highs will be in the
upper 40s to around 50 in the east/northeast with lower-middle 50s
across the central and western sections.
.Long Term (Saturday Night through Thursday)
Issued at 305 AM EDT Fri Oct 26 2012
Across the country, the big weather story early next week will
concern the mid-Atlantic and our northeastern states. Hurricane
Sandy, now a category one hurricane east of Florida is increasingly
likely to begin developing into into an intense extra-tropical
cyclone by Sunday well east of North Carolina. The majority of the
most recent guidance shows a deep 500mb trough forming over the
Appalachians. Should this occur, this cyclone would be pulled
northwest towards New York or southern New England by late Monday
with an exceptionally deep surface low and gale force winds.
The unusual track of this storm is a result of strong blocking
across the entire Atlantic basin. Upstream from this, across the
Lower Ohio Valley and midwest, northerly flow already in place
Sunday will simply not budge, continuing through at least Thursday.
A lengthy period of cool weather is practically certain for the
Commonwealth and southern Indiana. Clearing is forecast to have
taken place across southern Illinois and western Kentucky by late
Saturday. However, cloud cover is likely to linger across eastern
Kentucky into Sunday morning. Across central Kentucky, cloud cover
will remain a tricky forecast through Sunday as the NAM and the GFS
have contrasting forecasts on how quickly clouds erode over eastern
Kentucky.
At the surface, a ridge of high pressure extending southward along
the Mississippi River on Sunday simply will not budge. Northerly
surface winds are likely for our region for all of the early portion
of next week as the afore-mentioned deep nor`easter creeps slowly
over southern New England.
Temperatures will remain pretty consistent Sunday through Wednesday
in this basically blocky weather pattern. Expect highs in the lower
to mid 50 each day, with Monday potentially a bit cooler. Lows will
bottom out in the lower to mid-30s.
Expect clear to partly cloudy skies Monday through Thursday. It is
possible that overcast skies associated with the western edge of the
New England storm may push as far west as central Kentucky late
Monday or Tuesday if some of more western model solutions verify.
&&
.Aviation (12Z TAF Issuance)...
Issued at 645 AM EDT Fri Oct 26 2012
Surface cold front continues to make steady progress eastward this
morning. The front has slowed down a bit and is located along a
line from near KCVG-KFFT to just east of KBWG. Surface winds are
picking up slightly ahead of the front out of the southwest, but
will quickly veer around to the northwest after frontal passage.
Ceilings have fallen into the MVFR category behind the front and
they will likely remain there for the remainder of the day.
Radar returns show a batch of post frontal showers moving into
western Kentucky and southwest Indiana. These showers will head
east and start to impact KSDF/KBWG by 26/14-15Z and eventually get
over into the KLEX terminal later this afternoon. MVFR visibilities
and ceilings are expected to prevail this afternoon and into this
evening. The latest data does suggest that ceilings may eventually
fall into the high end of the IFR range tonight. Surface winds will
remain out of the northwest at 10-14kts with occasional gusts up to
18-20kts at times. The gusts will level off tonight and winds are
expected to become more northerly.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Short Term.......MJ
Long Term........JSD
Aviation.........MJ
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
645 AM EDT FRI OCT 26 2012
.Short Term (Today through Saturday)...
Issued at 326 AM EDT Fri Oct 26 2012
...Sharp cold front moving through the region today will result in
falling temperatures...
Well advertised potent upper level trough and associated surface
cold front are heading through the region early this morning. The
models have been playing catch up with respect to the timing and the
latest HRRR and RAP guidance seems to have a good handle on things.
Based on WSR-88D velocity moments, the front is just west of a
KSDF-KFTK-KBWG line. The front should cross the I-65 corridor
within the next hour and then head toward the I-75 corridor towards
sunrise. A brief period of breezy, perhaps gusty winds will
accompany the front as it pushes through with winds shifting from
the south to the northwest. Precipitation is lagging behind the
front by a few hours, so in the near term, dry conditions are
expected. Based on upstream observations, we`re seeing a 12-15
degree drop behind the front, so while temperatures in the central
sections are still in the mid-upper 60s, those reading will fall
quickly over the next couple of hours.
For today, the frontal boundary is forecast to push eastward through
the day. Some pre-frontal warming may occur in the east just ahead
of the front, but temperatures by and large will fall throughout the
day. All of the deterministic and ensemble guidance continues to
show that post-frontal precipitation is very likely, so we have
bumped up the clouds and precipitation chances a bit for today.
Highest PoPs today will be in the west and central sections with
higher PoPs in the east holding off until later this afternoon and
evening. As for temperatures, highs today will range from the upper
40s to the lower 50s in the west and central sections. Upper 50s to
the lower 60s are likely in the east, but these will occur early as
temperatures fall into the upper 40s to lower 50s by evening.
For tonight, the aforementioned frontal boundary will continue to
surge eastward. Lagging post-frontal precipitation band will likely
continue to slowly move eastward through the forecast area. It
appears that a weak upper level wave will pass overhead tonight,
which may enhance our PoP chances for the evening and early
overnight hours. Will keep chance PoPs in for the far
west/northwest sections with likely PoPs in the central and eastern
sections. Overall, best chances of rain tonight look to be over our
eastern forecast area. Precipitation should generally be exiting
the forecast area by dawn and drier air will attempt to punch into
our west/northwest sections late. With this drier air coming in,
we`re likely to see some partial clearing toward sunrise which will
allow for a gradient of temperatures across the area. Overnight
lows should range from the upper 30s in the far west/northwest with
lower 40s in the central and lower-mid 40s in the east.
For Saturday, high pressure to the west will continue to slowly
build into the region. This will result in clearing working across
the forecast area from west to east. Typically the models are too
fast at clearing things out. In addition, cold air advection aloft
will likely result in a stratocumulus deck building in. Partly
cloudy conditions look reasonable for areas west of I-65 with mostly
cloudy conditions east of I-65...though skies will likely become
mostly clear by evening. As for temperatures, highs will be in the
upper 40s to around 50 in the east/northeast with lower-middle 50s
across the central and western sections.
.Long Term (Saturday Night through Thursday)
Issued at 305 AM EDT Fri Oct 26 2012
Across the country, the big weather story early next week will
concern the mid-Atlantic and our northeastern states. Hurricane
Sandy, now a category one hurricane east of Florida is increasingly
likely to begin developing into into an intense extra-tropical
cyclone by Sunday well east of North Carolina. The majority of the
most recent guidance shows a deep 500mb trough forming over the
Appalachians. Should this occur, this cyclone would be pulled
northwest towards New York or southern New England by late Monday
with an exceptionally deep surface low and gale force winds.
The unusual track of this storm is a result of strong blocking
across the entire Atlantic basin. Upstream from this, across the
Lower Ohio Valley and midwest, northerly flow already in place
Sunday will simply not budge, continuing through at least Thursday.
A lengthy period of cool weather is practically certain for the
Commonwealth and southern Indiana. Clearing is forecast to have
taken place across southern Illinois and western Kentucky by late
Saturday. However, cloud cover is likely to linger across eastern
Kentucky into Sunday morning. Across central Kentucky, cloud cover
will remain a tricky forecast through Sunday as the NAM and the GFS
have contrasting forecasts on how quickly clouds erode over eastern
Kentucky.
At the surface, a ridge of high pressure extending southward along
the Mississippi River on Sunday simply will not budge. Northerly
surface winds are likely for our region for all of the early portion
of next week as the afore-mentioned deep nor`easter creeps slowly
over southern New England.
Temperatures will remain pretty consistent Sunday through Wednesday
in this basically blocky weather pattern. Expect highs in the lower
to mid 50 each day, with Monday potentially a bit cooler. Lows will
bottom out in the lower to mid-30s.
Expect clear to partly cloudy skies Monday through Thursday. It is
possible that overcast skies associated with the western edge of the
New England storm may push as far west as central Kentucky late
Monday or Tuesday if some of more western model solutions verify.
&&
.Aviation (06Z TAF Issuance)...
Issued at 1258 AM EDT Fri Oct 26 2012
VFR conditions will continue for the next couple of hours as a cold
front approaches from the northwest early this morning. Utilizing
upstream WSR-88D velocity patterns, the wind shift line is very
evident in the base velocity moments. Utilizing our distance/speed
tool, this front looks to push through KSDF around 0715-0745Z,
through KBWG around 0815-0845Z, and through KLEX around 0915-0945Z.
Upstream observations also show a period of gusty winds just behind
the front. So will be carrying sustained winds of 12-15kts with
gusts up to 20-24kts for an hour or two behind the front. Winds out
ahead of the front will be out of the south and southeast, but
quickly shift to the northwest after the front pushes through the
terminals.
Ceilings are expected to gradually lower behind the front with
ceiling likely settling near 2000ft AGL by 26/12Z. Post frontal
rain band is lagging behind, so am not expecting precipitation into
KSDF and KBWG until 26/13-14Z and even then that looks to be pretty
scattered so the VCSH wording from the previous forecast will be
used. Better chances of precipitation will likely hold off until
26/17-18Z where MVFR vsbys/cigs will likely prevail through the
remainder of the afternoon.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Short Term.......MJ
Long Term........JSD
Aviation.........MJ
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
620 AM CDT FRI OCT 26 2012
.UPDATE...FOR 12Z AVIATION DISCUSSION BELOW
&&
.DISCUSSION.../ISSUED 243 AM CDT FRI OCT 26 2012/
MAIN SHORT TERM CONCERN DEALS WITH CLD CVR TODAY WHICH WILL
CORRELATE TO SOME TEMPERATURE VARIATIONS IF MORE OR LESS STRATO-CU
DEVELOPS. OVER THE PAST TWO HRS...A LARGE CLEARING LINE HAS
DEVELOPED ACROSS CENTRAL AND SOUTHERN MN...ONLY THE FAR NW AND SW
HAD MOSTLY CLOUDY SKIES. LATEST RAP DOES HAVE THIS TYPE OF
SCENARIO OF CLEARING OUT FOR MOST OF THE FA DURING THE EARLY
MORNING HRS...BUT QUICKLY SATURATES UP TO ARND 90H BY 9 AM TO
NOON. WITH A LARGE AREA OF CLDS UPSTREAM...AND THE MEAN FLOW
CONTINUES FROM THE W/NW...WILL LEAD TOWARD CLOUDING UP AGAIN BY
NOON WITH TEMPERATURES CLOSE TO PREVIOUS FORECAST. SOME OF THE RAP
SOUNDINGS INDICATED VERY STEEP LAPSE RATES FROM THE SFC... UP TO
80H WITH CAPES 50 TO 100 J/KG. THE DEPTH OF THE MOISTURE AND
ASSOCIATED HIGHER CAPES OCCUR ACROSS MAINLY THE NE FA. ALTHOUGH
THE CRITICAL TEMPS THAT ARE ASSOCIATED WITH THE DEVELOPMENT OF ICE
CRYSTALS ARE LIMITED FOR MOST OF THE FA...SOME INDICATIONS THAT
THE DEPTH OF THE MOISTURE IN THE N/NE FA COULD ALLOW FOR SOME
-SNSH.
THE WEAK SYSTEM EXPECTED OVER THE WEEKEND HAS WEAKENED EVEN FURTHER
FOR THIS FORECAST PERIOD WHICH MEANS THAT THE CHC OF MEASURABLE
PRECIPITATION WILL BE VERY UNLIKELY. THE MAIN FACTOR IS THE VERY
DRY AIR MASS IN PLACE WHICH WILL TAKE TIME TO SATURATE THE THERMAL
COLUMN THIS WEEKEND. BEST CHC OF MEASURABLE PRECIPITATION WILL
OCCUR IN FAR SW/WC MN WHERE SLIGHTLY BETTER 85-70H DYNAMICS
EXISTS.
PAST THIS WEEKEND...THE OVERALL PATTERN WILL BE HIGHLY DEPENDENT
ON THE EVOLUTION OF HURRICANE SANDY AND HOW IT WILL TRANSLATE
ACROSS THE EASTERN U.S. CURRENT MODELS HAVE THIS SYSTEM MERGING
WITH A SECONDARY STORM SYSTEM MOVING SE ACROSS THE GREAT
LAKES/OHIO VALLEY OVER THE WEEKEND. CURRENT TRENDS HAVE THE
HURRICANE OR REMNANTS OF THIS TROPICAL SYSTEM...MOVING ONSHORE
NEAR THE NEW JERSEY/DELAWARE STATE LINE. AS THESE SYSTEMS
COMBINE...A VERY LARGE STORM IS EXPECTED TO SLOWLY MOVE FROM THE
MID ATLANTIC REGION...N/NW TO THE EASTERN GREAT LAKES. THIS WOULD
LEAD TO THE CONTINUED N/NW FLOW ACROSS THE UPPER MIDWEST.
BASICALLY THIS IS A DRY AND COOL PATTERN FOR OUR REGION. ..JLT..
&&
.AVIATION.../12Z TAF ISSUANCE/
MODELS CONTINUE TO INADEQUATELY PORTRAY THE LLVL MOISTURE
FIELDS...WHICH COMPLICATES THE CLOUD FORECAST FOR TODAY.
THANKFULLY THE DECK IS VFR LEVEL /3500-4500 FT/. THE RAP WAS
ADEQUATELY HANDLING THE CLEARING THAT OCCURRED OVERNIGHT...BUT
SEEMED TO BE BEGINNING TO WAVER PER 11Z SATELLITE IMAGERY...WHICH
DEPICTED A FAIRLY SOLID OVERCAST DECK MARCHING FROM WESTERN INTO
CENTRAL MN. WHILE SOME EROSION MAY OCCUR ON THE EASTERN PERIPHERY
OF THIS DECK...STILL THINK THAT A BKN-OVC DECK WILL REACH KMSP
AROUND 13Z AND KRNH/KEAU BETWEEN 14Z AND 16Z. THEN ANTICIPATE A
MOSTLY CLOUDY DAY...WITH NOTABLE SCATTERING OF THE CLOUDS THIS
EVENING AND TONIGHT.
WESTERLY WINDS SUSTAINED AT 12-15 KNOTS WILL GUST TO BETWEEN 20
AND 25 KNOTS THIS AFTENROON...AND THEN DIMINISH TO AROUND OR BELOW
5 KNOTS FOR THE OVERNIGHT HOURS INTO SATURDAY MORNING.
KMSP...
VFR EXPECTED THROUGH THE PERIOD. EXPECT BKN-OVC CLOUDS AROUND 4K
FT TO REACH KMSP BY 14Z...WITH CLEARING OCCURRING BY 00Z SATURDAY.
WINDS OF 270-280 AT 12 KTS WILL UST TO AROUND 18 KTS DURING THE
AFTERNOON HOURS...AND THEN DECREASE TO AROUND OR SLIGHTLY BELOW
05 KTS OVERNIGHT INTO SATURDAY MORNING.
/OUTLOOK FOR KMSP/
SAT...VFR. WINDS LGT AND VRBL.
SUN...MVFR POSSIBLE. SLIM CHANCE OF IFR. CHC -SN IN THE MORNING.
WINDS SE AT 5 KTS.
MON...VFR. WINDS SE AT 5 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
JLT/LS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
714 AM CDT FRI OCT 26 2012
.AVIATION...12Z KGRI TAF. NOT MUCH CHANGE FROM PREVIOUS
THINKING...AS CONFIDENCE IN CEILING TRENDS DURING THE NEXT 24
HOURS CONTINUES TO RUN WELL BELOW NORMAL THANKS TO THE EXTREMELY
POOR HANDLING OF AN EXPANSIVE MVFR STRATUS DECK BY SEVERAL
FORECAST MODELS AND ASSOCIATED NUMERICAL GUIDANCE. SURE
ENOUGH...THIS STRATUS DECK BASED AROUND 2500 FT HAS HELD FIRM ALL
NIGHT LONG...AND DESPITE WHAT SOME MODELS ARE SUGGESTING HAVE
SERIOUS RESERVATIONS THAT THIS STRATUS WILL BE GOING ANYWHERE
ANYTIME SOON. THAT BEING SAID...ITS CERTAINLY POSSIBLE THAT THE
CEILING LEVEL COULD RISE TO LOW-END VFR LEVELS AT SOME POINT
TODAY...BUT EVEN IF THIS WERE TO OCCUR THERE IS REALLY NO WAY OF
TELLING WHEN IT MIGHT HAPPEN...SO WILL CONTINUE TO KEEP THE MVFR
CIG IN PLACE THROUGH THE DAYTIME HOURS. FOR THE LATTER HALF OF THE
PERIOD...HAVE RELUCTANTLY ADVERTISED A LOW-END VFR CEILING...BUT
ITS NOT OUT OF THE QUESTION THAT MVFR COULD STILL BE HANGING TOUGH
SO STAY TUNED FOR POSSIBLE UPDATES. FORTUNATELY...CONFIDENCE IS
MUCH HIGHER THAT VISIBILITY WILL REMAIN UNRESTRICTED THROUGH THE
NEXT 24 HOURS...AND THAT SURFACE WINDS WILL REMAIN FAIRLY
LIGHT...AVERAGING AROUND 11KT DURING THE DAY AND THEN BECOMING
LIGHT/VARIABLE AND THEN LIGHT SOUTHERLY OVERNIGHT AS A SURFACE
HIGH PRESSURE RIDGE SLIDES ACROSS THE AREA.
&&
.PREV DISCUSSION... /ISSUED 333 AM CDT FRI OCT 26 2012/
SHORT TERM...TODAY THROUGH SUNDAY NIGHT. A COOLER PATTERN WILL BE
IN PLACE ACROSS THE CENTRAL PLAINS INTO THE WEEKEND UNDER THE
INFLUENCE OF AN UPPER TROUGH FM MANITOBA/ONTARIO ACROSS THE
NORTHERN/CENTRAL PLAINS. A 1033MB SURFACE HIGH WILL BUILD
SOUTHEAST FM MT/WY INTO NEBRASKA TODAY WITH LITTLE CHANGE IN THE
COLDER AIRMASS IN PLACE ACROSS OUR AREA. STRATUS CLOUDS HAVE
EXPANDED ACROSS CENTRAL NEBRASKA/NORTHERN KANSAS DURING THE PRE
DAWN HOURS...AND THIS CLOUD COVER HAS NOT BEEN HANDLED WELL BY MODELS.
PER SATELLITE IMAGERY...SOME CLEARING HAS COMMENCED ACROSS EASTERN
NEBRASKA INTO FAR NORTHEAST KANSAS AND HRRR PROGS SUGGEST THE
CLEARING MAY REACH OUR EAST/NORTHEAST COUNTIES...WHILE THE LOWER
CLOUDS MIGRATE TO THE SOUTHWEST. HAVE TO ADMIT CONFIDENCE IS NOT
HIGH ON EXTENT OF CLOUD COVER TODAY WHICH WILL ULTIMATELY HAVE AN
IMPACT ON OUR HIGH TEMPERATURES. BELIEVE ITS BEST TO KEEP THINGS
CONSERVATIVE AND WILL PLACE MAX TEMPS AROUND 40F IN NEB/LOW 40S IN NC
KANSAS. THE CLOUDS LOOK TO SCATTER TONIGHT...BEFORE INCREASING
AGAIN ON SATURDAY AHEAD OF NEXT APPROACHING WAVE. IN DECREASING
CLOUDS...DRIER/COLD AIRMASS WE ARE LOOKING AT ANOTHER COLD NIGHT
WITH LOW TEMPS WELL BELOW FREEZING.
SATURDAY THE FORECAST TURNS A LITTLE MORE INTERESTING AS 125KT H3
JET PROGRESSES SOUTHEAST IN NORTHWEST FLOW/ON BACK SIDE OF TROUGH
WITH DIVERGENCE ALOFT INCREASING IN OUR NORTHERN CWA IN LFQ OF JET.
A DECENT H7 SHORTWAVE TROUGH CROSSES NORTHERN/CENTRAL NEBRASKA IN
THE AFTN. WAA INCREASES AHEAD OF APPROACHING WAVE WITH ISENTROPIC
LIFT NOTED IN AFTN ON THE 290K SFC ACROSS OUR NORTHERN ZONES.
FORECAST SOUNDINGS INDICATE MOISTURE LACKING BELOW H75 SO NOT
LOOKING FOR MUCH IN THE WAY PCPN ATTM...BUT CANNOT RULE OUT
SPRINKLES AND WILL ADD IN POTENTIAL FOR VALLEY/GREELEY COUNTIES.
MID LEVEL SHORTWAVE TROUGH AXIS PASSES SATURDAY NIGHT AND HEIGHTS
GRADUALLY BEGIN TO RISE ON SUNDAY. LLVL FLOW REMAINS WEAK AS SFC
RIDGE SLOWLY TREKS EAST AND MODELS INDICATE POTENTIAL FOR
INCREASING MID/HIGH CLOUDS. NOT LOOKING AT MUCH WARMING JUST
YET...WITH HIGHS IN THE MID/LOW 50S. THE COOLER AIRMASS SHIFTS
EAST OF THE MISSOURI RIVER SUNDAY NIGHT WITH TEMPS MODERATING MORE
SO HEADING INTO THE WORKWEEK.
LONG TERM...MONDAY THROUGH THURSDAY. WHILE THE EVOLUTION OF
HURRICANE SANDY AND THE EXTENT OF EAST COAST IMPACTS WILL GARNER THE
BRUNT OF NATIONAL ATTENTION NEXT WEEK...IT STILL APPEARS THE CENTRAL
PLAINS WILL QUIETLY EXPERIENCE SEVERAL DAYS OF DRY...TRANQUIL...AND
SEASONABLY MILD CONDITIONS INCLUDING HALLOWEEN. ANY CHANGES TO THE
PREVIOUS FORECAST...IF ANY AT ALL DURING PERIODS...WERE VERY MINOR AND
PRIMARILY INVOLVED A VERY SLIGHT 1-2 DEGREE UPWARD NUDGE IN DAILY
HIGH TEMPERATURES. IN GENERAL...DAILY HIGHS ARE FORECAST TO BE
WITHIN A FEW DEGREES EITHER SIDE OF NORMALS...SO ALL IN ALL TYPICAL
MID-FALL WEATHER.
STARTING WITH MONDAY/MONDAY NIGHT...AGREEMENT BETWEEN THE 00Z
ECMWF/GFS SOLUTIONS IS FAIRLY SIMILAR...ALTHOUGH THE EC SUGGESTS A
BIT STRONGER MID LEVEL RIDGE WILL EDGE TOWARD THE AREA WHILE BECOMING
CENTERED ALONG AN AXIS FROM THE DESERT SOUTHWEST TO THE NORTHERN
ROCKIES...WHILE THE GFS WHICH IS FARTHER EAST WITH SANDY KEEPS MORE
OF A BROAD NORTHWEST FLOW INTACT OVER THE REGION. HOWEVER...EVEN THE
GFS SOLUTION KEEPS ANY CLIPPER-TYPE SHORTWAVE SYSTEMS AND ASSOCIATED
MINOR PRECIPITATION EVENTS NO CLOSER THAN A CORRIDOR FROM SOUTH
DAKOTA THROUGH IA. HIGH TEMPS ARE FORECAST TO RANGE MID 50S
NORTHEAST TO LOW 60S SOUTHWEST...WITH OVERNIGHT LOWS MAINLY
MID-UPPER 30S.
TUESDAY/TUESDAY NIGHT...OVERALL VERY LITTLE CHANGE AS THE DEEP
TROUGH ASSOCIATED WITH SANDY DOMINATES THE EASTERN CONUS...WHILE THE
CENTRAL PLAINS REMAINS UNDER NORTH-NORTHWEST FLOW ON THE EASTERN
PERIPHERY OF THE ROCKY MOUNTAINS RIDGE AXIS. HIGH TEMPS ARE
ADVERTISED VERY SIMILAR TO MONDAY...RANGING MID 50S NORTHEAST TO MID
60S SOUTHWEST.
WEDNESDAY/WEDNESDAY NIGHT...THE BLOCKING PATTERN REMAINS FIRMLY IN
PLACE...AS THE MID LEVEL RIDGE AMPLIFIES EVEN MORE OVER THE CENTRAL
CONUS IN BETWEEN THE EASTERN TROUGH AND THE NEXT UPSTREAM TROUGH
MOVING ONTO THE PACIFIC COAST. BARRING MAJOR CHANGES...HALLOWEEN
WEATHER CONDITIONS DON/T GET MUCH MORE TRANQUIL THAN THIS...WITH
AFTERNOON HIGHS RANGING UPPER 50S NORTHEAST TO MID 60S
SOUTHWEST...AND EVENING READINGS SETTLING INTO THE 40S FOR
TRICK-OR-TREATERS.
THURSDAY...THE HEART OF THE EXPANSIVE NORTH-SOUTH MID LEVEL RIDGE
AXIS SHOULD EDGE EAST A BIT MORE TOWARD THE CENTRAL PLAINS FROM THE
ROCKIES...AS THE UPSTREAM WEST COAST WAVE FINALLY STARTS MAKING A
BIT OF EASTWARD PROGRESS. YET AGAIN FORECAST HIGH TEMPS ARE ALMOST
IDENTICAL TO THE PREVIOUS DAY...RANGING UPPER 50S NORTHEAST TO MID
60S SOUTHWEST ACROSS THE CWA.
LOOKING BEYOND THE OFFICIAL FORECAST PERIOD...THE NEXT HALFWAY
DECENT CHANCE OF PRECIPITATION...AND LIKELY IN THE FORM OF RAIN AND
NOT SNOW...SHOULD ARRIVE GENERALLY DURING THE NEXT FRIDAY
NIGHT-SATURDAY TIME FRAME AS THE WESTERN TROUGH FINALLY TRACKS INTO
THE PLAINS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AVIATION/LONG TERM...PFANNKUCH
AREA FORECAST DISCUSSION
NWS BUFFALO NY
735 AM EDT FRI OCT 26 2012
.SYNOPSIS...
RETREATING HIGH PRESSURE WILL MAINTAIN PLEASANTLY WARM CONDITIONS THIS
MORNING...BUT A COLD FRONT APPROACHING FROM THE WEST BRING
INCREASING CLOUDS THIS AFTERNOON. RAIN WILL FOLLOW THE FRONT...WITH
PERIODS OF RAIN AND COOLER TEMPERATURES FOR MOST OF THE WEEKEND.
EARLY NEXT WEEK THE REMNANTS OF HURRICANE SANDY MAY APPROACH THE
REGION BUT SIGNIFICANT FORECAST UNCERTAINTY LEAVES THE DETAILS YET
TO BE DETERMINED. WHAT IS MORE CERTAIN IS AN EXTENDED PERIOD OF RAIN
AND COOL TEMPERATURES FOR MUCH OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE MORNING WILL START OF WITH MOSTLY SUNNY SKIES ACROSS MOST OF
WESTERN NEW YORK AS A STRATUS CLOUD DECK REMAINS SOUTHEAST OF THE
CWA. CLOUDS WILL SPREAD IN FROM WEST TO EAST THIS AFTERNOON...BUT
THIS SHOULD PROVIDE AMPLE TIME FOR TEMPERATURES TO RISE AHEAD OF
THE FRONT. MOST GUIDANCE WAS TOO COOL ON HIGHS YESTERDAY AND LAST
NIGHT...AND EXPECT THIS TREND WILL CONTINUE TODAY. FORECAST IS
SEVERAL DEGREES ABOVE MOST GUIDANCE...EXPECTING HIGHS IN THE LOWER
70S IN MOST LOCATIONS...MID 70S IN THE GENESEE VALLEY AND
ROCHESTER METRO AREA. THIS SHOULD FALL SHY OF RECORDS...BUT NOT
FAR OFF WITH THE RECORD TODAY IN BUFFALO 77 AND IN ROCHESTER 79.
00Z MODEL GUIDANCE IS FAIRLY CONSISTENT IN BRINGING A COLD FRONT
INTO WESTERN NEW YORK EARLY THIS AFTERNOON...THEN STALLING THE
BOUNDARY ACROSS CENTRAL NEW YORK TONIGHT. NOTED THE HRRR AND THE
06Z RUN OF THE NAM ARE A TAD FASTER THAN PREVIOUS FORECASTS...AND
ARE WELL IN LINE WITH THE FRONTS CURRENT POSITION...SO WILL SPEED
UP THE TIMING OF THE FRONT TO MATCH THESE MODELS.
FOR THE MOST PART...EXPECT MOST OF THE PRECIPITATION WITH THIS
FRONT TO BE ANAFRONTAL OR BEHIND THE COLD FRONT. BOTH MODEL
GUIDANCE AND UPSTREAM OBSERVATIONS SUPPORT THIS. THERE IS SOME
CONVECTIVE GENERATED QPF OUT AHEAD OF THE FRONT THIS
AFTERNOON...WHICH SHOULD RESULT IN ONLY SCATTERED SHOWERS IN
WESTERN PORTIONS OF THE CWA. USING A BLEND OF THE LAST TWO RUNS OF
THE NAM/RGEM/SREF/GFS...A CONSENSUS QPF BRINGS STEADIER RAINS IN
FROM WEST TO EAST THIS EVENING AND LATER TONIGHT. WITH BUFKIT
SHOWING LIFT FROM THE MID- LEVELS ALONG A TIGHT 850MB TEMPERATURE
GRADIENT...FEEL CONFIDENT IN BRINGING CATEGORICAL POPS INTO FAR
WESTERN SECTIONS LATE TONIGHT...DESPITE ONLY MODEST QPFS.
MEANWHILE...TEMPERATURES WILL BE MARKEDLY COOLER TONIGHT...AS THE
FRONT USHERS IN COOLER AIR AT THE SURFACE...TEMPERATURES SHOULD DROP
TO MORE SEASONABLE LEVELS. LOWS TONIGHT WILL RANGE FROM THE MID 40S
IN WESTERN SECTIONS...TO THE LOWER 50S EAST OF LAKE ONTARIO. EXPECT
AREAS OF FOG TO DEVELOP TOO...AS MOISTURE INCREASES WITH THE FRONTAL
BOUNDARY.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
THIS TIME PERIOD WILL FEATURE COOL...DREARY...RAINY DAYS ACROSS WNY
AS A FRONTAL BOUNDARY WILL BE STALLING JUST TO OUR EAST. TOWARDS THE
NORTHERN FINGER LAKES AND EASTERN LAKE ONTARIO REGION RAIN CHCS WILL
BECOME INCREASINGLY LIKELY DEEPER INTO THE WEEKEND WITH A COOLER
SUNDAY IN STORE.
THE UPPER AIR PATTERN TO START THE WEEKEND FEATURES AN 500 HPA
TROUGH DIGGING INTO THE CENTRAL PLAINS...WITH A +2SD 500 RIDGE OVER
EASTERN ATLANTIC CANADA AND TOWARDS GREENLAND. A COLD FRONT ON
SATURDAY WILL BE STALLING JUST TO OUR EAST AS IT ENCOUNTERS THIS
UPPER LEVEL RIDGE TO OUR EAST. MOISTURE BEHIND THIS FRONT WILL SHAPE
AN ANA FRONTAL SIGNATURE WITH A 120 KNOT 250 HPA JET`S RIGHT
ENTRANCE REGION CENTERED OVER SOUTHERN ONTARIO CANADA PENINSULA
ALONG WITH A NEARING 500 HPA SHORT WAVE PROVIDING LIFT.
A PERIOD OF LIGHT RAIN IS EXPECTED ACROSS WNY ON SATURDAY...WHILE TO
THE EAST OF A TIGHT 850 HPA BAROCLINIC BOUNDARY CHANCES FOR RAIN WILL
BE LESS...AND WILL USE CHC WORDING. MOISTURE PROFILES SUGGEST
COPIOUS MOISTURE IN THE BOUNDARY LAYER WHICH WILL LEAD TO AREAS OF
HIGHER ELEVATION FOG WITH CLOUD CIGS LOWERING. ALOFT A TIGHT 850 HPA
BAROCLINIC BOUNDARY WILL BE SEPARATING A MILDER DAY TO THE EAST
WHERE AFTERNOON HIGHS MAY NEAR 60F...WHILE TO THE WEST 850 HPA
TEMPERATURES LOWERING TO 0 TO -1C WILL ALLOW FOR UPPER 40S AND LOWER
50S.
BY SATURDAY NIGHT RAIN WILL PUSH MARGINALLY DEEPER INTO THE CWA WITH
THE EASTWARD EXTEND OF THE RAIN ASSOCIATED WITH THE FRONTAL BOUNDARY
REACHING THE EASTERN LAKE ONTARIO REGION. RAINFALL SATURDAY AND
SATURDAY NIGHT WILL HOURLY BE ON THE LIGHT SIDE...BUT A PROLONGED
RAIN WILL LEAD TO 24 HOUR TOTALS OF AROUND HALF AN INCH TOWARDS THE
WEST...TO AROUND A TENTH OF AN INCH TO THE EAST. LOWS SATURDAY NIGHT
WILL FALL INTO THE UPPER 30S TO THE WEST...WHILE MID 40S WILL BE
FOUND TO THE EAST.
SUNDAY THE STALLED FRONTAL BOUNDARY WILL BEGIN TO BE SHOVED WESTWARD
AS TROPICAL SYSTEM SANDY RIDES NORTHWARD UP THE ATLANTIC COASTLINE.
ALOFT A 120 KNOT 250 HPA RIGHT ENTRANCE REGION WILL REMAIN ACROSS
WNY AND WITH PLENTIFUL MOISTURE IN THE LOWER LAYERS EXPECT A
CONTINUED PERIOD OF RAIN ACROSS WNY. THOUGH AREAS ACROSS EASTERN
PORTIONS OF THE CWA MAY START THE DAY SUNDAY DRY...MOISTURE FROM
SANDY WILL BEGIN TO INTERACT WITH THE UPPER LEVEL TROUGH AND WE
SHOULD SEE AN INCREASE IN RAIN ACROSS EASTERN ZONES WITH RAIN
ENTERING FROM THE SOUTHEAST.
BY SUNDAY A MORE UNIFORM SPREAD IN TEMPERATURES AT 850 HPA WILL BE
FOUND RANGING FROM -1 TO +4C ACROSS THE AREA. EXPECT COOL CONDITIONS
TO PERSIST UNDER CLOUDY SKIES WITH HIGHS LARGELY IN THE 40S. AREAS
THAT MAY TOP THE 50F MARK WILL BE TO THE EAST.
SUNDAY NIGHT HURRICANE SANDY WILL BE CHURNING OFF THE CAROLINA
COASTLINE HOWEVER MOISTURE WELL AHEAD OF THIS HURRICANE WILL BE
REACHING THE MID ATLANTIC STATES. AT THE SFC A COOL NORTHERLY FLOW
WILL CONTINUE...BUT ALOFT A WARM MOIST CONVEYOR BELT WILL BE FOUND
WITH EASTERLY MOIST ISENTROPIC LIFT FLOW THROUGH THE NIGHT. THIS
FLOW FROM THE EAST WILL SET THE STAGE FOR PERIODS OF LIGHT RAIN
ACROSS OUR REGION. HEAVIEST RAIN WILL LIKELY BE TO THE EAST THOUGH
AT THIS STAGE HOWEVER UNCERTAINTY WITH THE TRACK OF SANDY AND WHERE
DEEP MOISTURE PLUMES WILL BE FOUND OUR FORECAST UNCERTAINTY STARTS
TO INCREASE.
THOUGH WE WILL BE WARMING ALOFT...ESPECIALLY TOWARDS THE EAST...THE
BOUNDARY LAYER COOL NORTHERLY WINDS WILL CONTINUE. THIS WILL LEAD TO
OVERNIGHT LOWS SUNDAY NIGHT RANGING FROM THE LOW 30S ACROSS INTERIOR
SOUTHERN NEW YORK STATE...TO LOW 40S ACROSS THE NORTH COUNTRY. AT
THIS POINT WE STILL CANNOT RULE OUT HIGHER ELEVATION SNOW ACROSS
INTERIOR SOUTHERN TIER.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
THE FOCUS THIS TIME PERIOD WILL OBVIOUSLY BE ON SANDY AND ITS
IMPACTS UPON NOT ONLY WESTERN AND NORTH CENTRAL NEW YORK...BUT ALONG
THE ENTIRE EASTERN COASTLINE.
FIRST A LOOK AT THE MAJOR FEATURES FOR THIS TIME PERIOD. HURRICANE
SANDY IS CURRENTLY SPINNING ON A NORTHERN TRACK JUST NORTH OF THE
BAHAMAS THIS MORNING. ON WATER VAPOR IMAGERY A SHORT WAVE IS NEARING
BRITISH COLUMBIA...AND THIS FEATURE WILL CARVE A DEEPER CENTRAL US
TROUGH THAT WILL SLIDE EASTWARD AND CAPTURE SANDY. TO OUR EAST A
+2SD RIDGE AT 500 HPA IS LOCATED ACROSS EASTERN ATLANTIC CANADA AND
TOWARDS GREENLAND. THIS RIDGE OVER GREENLAND SUPPORTS THE NEGATIVE
PHASE OF THE NAO...AND A NEGATIVE PHASE OF THE NAO CAN ELUDE TO A
BLOCKING PATTERN. THIS BLOCKING PATTERN IS WHAT WILL ALLOW THE
TROUGH TO OUR WEST TO CAPTURE AND TURN SANDY WESTWARD ACROSS THE
EASTERN COASTLINE.
THE DETERMINISTIC 26/00Z MODEL OF THE ECMWF CONTINUES TO DRIVE SANDY
INTO THE DELMARVA PENINSULA MONDAY...WHILE THE DETERMINISTIC 26/00Z
GFS PUSHES SANDY WESTWARD ALONG THE SOUTHERN SHORELINE OF LONG
ISLAND THROUGH THE COURSE OF TUESDAY. THE GEFS MEMBERS SPREAD FROM
NEAR THE EUROPEAN SOLUTION...WHILE SOME MEMBERS BRING SANDY MUCH
FARTHER NORTHWARD MAKING LANDFALL IN NEW ENGLAND. THAT SAID WE ARE
FAIRLY CERTAIN SANDY WILL MAKE LANDFALL SOMETIME EARLY NEXT WEEK
WITH IMPLICATIONS NOW LEANING TOWARDS A PROLONGED RAIN WITH THE
POTENTIAL FOR RIVER AND URBAN FLOODING AND POSSIBLE HIGH WIND THREAT.
IT IS STILL TO EARLY AND TOO MUCH UNCERTAINTY FOR ANY
HEADLINES...BUT WE WILL CONTINUE TO MENTION THE THREATS IN OUR HWO
PRODUCT AS WELL AS HERE BELOW IN THE AFD.
RAIN AND FLOODING...BOTH THE ECMWF AND GFS LINGER A FRONTAL BOUNDARY
ACROSS WNY...AND MOISTURE SURGING WESTWARD TOWARDS THIS FRONT COULD
LEAD TO A PERIOD OF MODERATE TO HEAVY RAIN BEGINNING AS EARLY AS
MONDAY. AS SANDY MOVES INLAND EXPECT A PERIOD OF RAIN ASSOCIATED
WITH THE TROPICAL SYSTEM TO PASS ACROSS WESTERN AND NORTH CENTRAL
NEW YORK IN THE MONDAY THROUGH WEDNESDAY TIMEFRAME. IT IS STILL TOO
EARLY TO TIME WHEN THE HEAVIEST RAIN IS BASED ON UNCERTAINTY OF THE
TRACK BUT WE ARE FAIRLY CERTAIN THAT AT LEAST SOME RAIN WILL BE NEAR
US THROUGH THE TIME PERIOD.
A LOOK AT THE GEFS MODEL ENSEMBLE RIVER FORECASTS SHOWS THAT SOME OF
OUR CREEKS AND RIVERS...ESPECIALLY ACROSS WESTERN NEW YORK WILL NEED
TO BE WATCHED FOR RIVER HEIGHT RISES. A FEW MEMBERS OF THIS ENSEMBLE
DO BRING SEVERAL OF OUR CREEKS...BOTH QUICK AND SLOW RISERS INTO
MINOR FLOODING IN THE MONDAY THROUGH WEDNESDAY TIMEFRAME. WITH RAINFALL
SINCE SEPTEMBER 1ST AROUND AN INCH OR SO ABOVE NORMAL...AND COMBINED
WITH THE WEEKEND RAIN...OUR CREEKS AND RIVERS THAT WERE PRETTY LOW
OVER THE SUMMER HAVE LARGELY RECOVERED FROM THEIR LOW FLOW. THIS
INCREASE IN RIVER FLOW THIS AUTUMN WILL ONLY INCREASE THE
POSSIBILITIES OF ANY RIVER FLOODING NEXT WEEK...AS WELL AS SMALL
CREEKS.
THERE IS ALSO THE POTENTIAL FOR URBAN AND POOR DRAINAGE FLOODING.
AGAIN TOO EARLY TO PLACE QPF WITH THIS SYSTEM...BUT SEVERAL INCHES
OF RAIN IS POSSIBLE ACROSS THE FORECAST AREA.
WIND...THE SECOND CONCERN WITH SANDY FOR OUR AREA WILL BE WIND. AS
SANDY PUSHES INLAND AND NEARS OUR REGION AN INCREASE IN WIND
SPEED...LIKELY A NORTH TO NORTHEAST WIND... IS EXPECTED. AGAIN
MODELS WILL LIKELY FLUCTUATE ON WIND SPEED WITH THE TRACK OF THE
SYSTEM AND PINPOINTING SPEEDS AT THIS TIME IS UNCERTAIN. THE HIGHEST
WINDS SPEEDS WILL LIKELY COME MONDAY NIGHT AND INTO TUESDAY BASED
OFF BOTH THE CURRENT MODEL RUNS OF THE 00Z ECMWF AND GFS. WITH THIS
WIND DIRECTION THE AREA MOST LIKELY IMPACTED BY THE WINDS WILL BE
LAKE ONTARIO AND ITS SOUTHERN SHORELINES. PAST EVENTS HAVE SHOWN
EVEN SUBWARNING WIND SPEEDS CAN FALL TREES AS THE NORTHEAST WIND
DIRECTION IS NOT A COMMON HIGH SPEED DIRECTION.
SNOW...THIS IMPACT IS BECOMING LESS LIKELY AS WARM AIR WRAPPING
ACROSS OUR REGION WILL LEAVE THE BOUNDARY LAYER TOO WARM TO SUPPORT
SNOW. TEMPERATURES WILL COOL SOME AT NIGHT AND THERE IS STILL A CHC
FOR HIGHER ELEVATION SNOW MONDAY NIGHT ACROSS SOUTHWESTERN NEW YORK
STATE.
THOUGH THE REMNANT OF SANDY`S CIRCULATION WILL BE PULLING TO THE
NORTH AND EAST BY THURSDAY EXPECT CLOUDY SKIES WITH THE CHANCE FOR
RAIN SHOWERS TO CONTINUE. TEMPERATURES ALOFT AT 850 HPA REMAIN ABOVE
ZERO LEADING TO NO THREAT FOR SNOW THURSDAY AS THE SYSTEM PULLS AWAY
FROM THE AREA.
DAYTIME TEMPERATURES THROUGH THIS TIME PERIOD WILL START COOL AND
BELOW NORMAL TOWARDS THE WEST...WHILE WARMER AIR TOWARDS THE EAST
WILL ALLOW FOR NORMAL TO ABOVE NORMAL TEMPERATURES THROUGH THE
PERIOD. WITH THE TROPICAL SYSTEM AND CLOUDS THROUGH THE NIGHT
OVERNIGHT LOWS WILL AVERAGE A FEW DEGREES ABOVE NORMAL.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS WILL PREVAIL TODAY...WITH MOSTLY CLEAR SKIES
THROUGH AROUND 18Z. VFR LEVEL CLOUDS WILL INCREASE FROM WEST TO
EAST DURING THE AFTERNOON WITH THE PASSAGE OF A COLD FRONT. A FEW
SHOWERS MAY DEVELOP IN THE WESTERN SOUTHERN TIER LATE IN THE
DAY...AFTER 21Z. CIGS WILL LOWER BEHIND THE FRONT THIS EVENING...WITH
ANAFRONAL SHOWERS ALSO LIKELY. CONDITIONS WILL CONTINUE TO LOWER
THROUGH THE NIGHT AND MOISTURE TRAPPED BENEATH A SHALLOW INVERSION
INCREASES OVERNIGHT. ALSO...A WAVE WILL TRACK ALONG THE STALLED
BOUNDARY...WHICH WILL BRING STEADIER RAINS TO BUF/IAG/JHW LATE TONIGHT.
OUTLOOK...
SATURDAY AND SUNDAY...PERIODS OF RAIN WITH AREAS OF MVFR/IFR.
MONDAY AND TUESDAY...RAIN LIKELY WITH AREAS OF IFR. RAIN MAY MIX
WITH SOME WET SNOW AT TIMES ACROSS THE HIGHER TERRAIN OF THE
WESTERN SOUTHERN TIER.
&&
.MARINE...
WINDS HAVE TAPERED OFF JUST A BIT ACROSS LAKE ONTARIO...WITH WAVES
EXPECTED TO BE 4 FT OR LESS IN THE NEARSHORES. A COLD FRONT WILL
SLOWLY CROSS THE WATERS...ENTERING LAKE ONTARIO AROUND NOON...WITH
THE FRONT SLOWING AND STALLING OUT TONIGHT.
A WIND SHIFT TO NORTHERLY WILL SET UP BEHIND THE FRONT...LIKELY TO
LAST THROUGH THE WEEKEND. THE CURRENT WAVE FORECAST CALLS FOR
POSSIBLE SMALL CRAFT CONDITIONS DEVELOPING ON SATURDAY INTO SUNDAY.
THERE IS A POTENTIAL FOR STRONGER WINDS EARLY NEXT WEEK AS THE
REMNANTS OF SANDY MAY IMPACT THE REGION...BUT THERE CONTINUES TO BE
SIGNIFICANT UNCERTAINTY ON THE SPECIFICS.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...APFFEL
MARINE...APFFEL/THOMAS
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1040 AM CDT FRI OCT 26 2012
.DISCUSSION.../ISSUED AT 1040 AM CDT/
BIGGEST CHALLENGE TODAY REMAINS TO BE CLOUD COVER ACROSS THE AREA.
CURRENT SATELLITE IMAGE SHOWING MUCH OF THE REGION SOCKED IN WITH
STRATUS. THE RUC CONTINUES TO LOOK LIKE THE MODEL OF CHOICE WITH
REGARD TO LOW LEVEL RH FIELDS...SO FOLLOWED THIS IN KEEPING CLOUDS
OVER THE AREA THROUGH AT LEAST LATE THIS AFTERNOON OR EVENING. WITH
THE THOUGHT THAT LITTLE SUNSHINE WILL BE REALIZED...LOWERED HIGHS A
DEGREE OR TWO. UPDATES OUT.
&&
.PREV DISCUSSION.../ISSUED AT 336 AM CDT/
MAIN FORECAST PROBLEM TODAY WILL BE THE CLOUD COVER. MODELS HAVE
HANDLED THE LOW CLOUD COVER VERY POORLY. DRIER H85 AIR OVER MN AND
IOWA HAVE BROUGHT SOME CLEARING TO SECTIONS OF NORTHWEST IOWA AND
THIS DRIER AIR IS PROGGED TO BACK WEST TO NEAR I29 THIS
MORNING...AND THEN INCREASE AGAIN DURING THE AFTERNOON FROM THE
WEST. SO WILL LIKELY SEE MORE SUNSHINE EAST OF I29 TODAY WHILE
WESTERN CWA REMAINS MOSTLY CLOUDY. HOW FAR WEST ANY CLEARING GETS
TODAY IS AN ISSUE. AS FAR WEST AS I29 MAY BE OPTIMISTIC BASED ON
CURRENT TRENDS MOST AREAS WILL LIKELY STAY MOSTLY CLOUDY THROUGH THE
DAY WITH SOME CLEARING DURING THE NIGHT. WILL BE ANOTHER COLD DAY
WITH HIGHS ONLY IN THE UPPER 30S TO MID 40S.
FOCUS THEN SHIFTS TO SATURDAY AND WAVE DROPS SOUTHEAST IN NORTHWEST
FLOW ALOFT. ASSOCIATED WEAK INVERTED TROF MOVES INTO WESTERN CWA
SATURDAY AND THEN WEAKENS SATURDAY NIGHT. AM EXPECTING SOME LIGHT
PRECIPITATION TO DEVELOP ACROSS WESTERN CWA SATURDAY IN THE FORM OF
LIGHT RAIN OR LIGHT SNOW. THIS PRECIPITATION MAY HAVE A HARD TIME
GETTING MUCH FURTHER EAST OF I29 SATURDAY NIGHT AS SOMEWHAT OF A
KEEWATIN HIGH KEEPS LOWER LEVELS DRY TO THE EAST OF I29 AND THUS
WILL BE HARD TO SATURATE LOW LEVELS AS WEAK WAVE MOVES EAST OF I29
LATER SATURDAY NIGHT. SO WILL KEEP HIGHEST PRECIPITATION CHANCES
WEST OF I29 SATURDAY NIGHT WITH ONLY A CHANCE OF LIGHT SNOW TO THE
EAST. COULD SEE AN INCH OR SO OF SNOW WEST OF I29 SATURDAY LIGHT
WITH PERHAPS LITTLE IF ANY SNOW TO THE EAST. WITH INCREASING CLOUD
COVER AND LOW LEVEL COLD SOUTHEAST FLOW...HIGH TEMPERATURES WILL
STRUGGLE TO CLIMB THROUGH THE 40S...ALTHOUGH HIGHS COLD TOP NEAR 50
ALONG THE MISSOURI RIVER.
AS SYSTEM PULLS AWAY...CWA IS LEFT IN LOW LEVEL SOUTHEAST FLOW AND
CLOUD COVER ON SUNDAY MAY BE HARD TO CLEAR AS STRATUS MAY BE FAIRLY
WIDESPREAD AGAIN. DRIER AIR DOES MOVE INTO WESTERN CWA DURING THE
DAY...BUT THE QUESTION IS IF THIS WILL BE ENOUGH TO SCOUR OUT LOWER
CLOUDS. FOR NOW WILL BE A LITTLE MORE PESSIMISTIC AND ONLY HAVE
SKIES BECOME PARTLY CLOUDY ACROSS THE WEST. TEMPERATURES WILL REMAIN
COLD WITH HIGHS AGAIN ONLY IN THE 40S MOST PLACES.
BELOW NORMAL TEMPERATURES WILL PERSIST ON MONDAY WITH BLOCKING
PATTERN OFF EAST COAST KEEPS COOLER AIR FUNNELING SOUTHEAST ACROSS
CWA.
TUESDAY AND WEDNESDAY SHOULD BE A BIT WARMER...BUT THAT WILL BE
DEPENDENT ON HOW STORM OFF EAST COAST EVOLVES. WITH RETROGRADING
LOW...COOLER TEMPERATURES LIKELY TO REMAIN IN PLACE ACROSS THE CWA
AND NOT AS PROGRESSIVE EAST AS MODEL MAY INDICATE. SO NOT
SIGNIFICANTLY WARMER MONDAY TUESDAY THROUGH THURSDAY. WILL LEAVE
FORECAST DRY AFTER SATURDAY NIGHT...BUT A WEAK WAVE DROPPING
SOUTHEAST TUESDAY COULD PRODUCE SOME LIGHT RAIN...MAINLY OVER
WESTERN CWA AS HIGH PRESSURE OVER THE WESTERN GREAT LAKES REGION
BLOCKS PROGRESSION FURTHER EAST.
&&
.AVIATION.../FOR THE 12Z TAF ISSUANCE/
MAINLY VFR CONDITIONS EXPECTED THROUGH THE PERIOD. CLOUD DECK IS
HOLDING STRONG ACROSS THE AREA AND IS NOT BEING HANDLED WELL BY MOST
MODELS. THE RAP IS THE ONLY GUIDANCE THAT HAS THE CLOUD DECK...AND
IT KEEPS THE CLOUDS AROUND THROUGH THE DAY. THIS SEEMS
REASONABLE...AS EVEN THE NAM AND GFS SUGGEST CLOUDS WOULD REFORM AS
MIXING COMMENCED LATER THIS MORNING. THUS WILL KEEP CLOUDS IN
THROUGH THE DAY AND INTO THIS EVENING. THINK CIGS IN THESE CLOUDS
WILL STAY VFR AROUND 4K FEET...ALTHOUGH SOME ISOLATED MARGINAL MVFR
IS POSSIBLE THIS MORNING AND THEN AGAIN THIS EVENING. AS WE LOSE THE
NORTHWESTERLY FLOW AND WINDS GO CALM OR LIGHT SOUTHERLY
TONIGHT...THINK CLOUD DECK SHOULD FINALLY DISSIPATE. THIS COULD
ALLOW FOR SOME FOG FORMATION WITH MOIST LOW LEVELS REMAINING.
HOWEVER CURRENTLY THINK AN INCREASE IN HIGH CLOUDS MIGHT PREVENT
THIS...SO WILL LEAVE FOG OUT OF THE TAF FOR NOW. /CHENARD
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
626 AM CDT FRI OCT 26 2012
.DISCUSSION.../ISSUED AT 336 AM CDT/
MAIN FORECAST PROBLEM TODAY WILL BE THE CLOUD COVER. MODELS HAVE
HANDLED THE LOW CLOUD COVER VERY POORLY. DRIER H85 AIR OVER MN AND
IOWA HAVE BROUGHT SOME CLEARING TO SECTIONS OF NORTHWEST IOWA AND
THIS DRIER AIR IS PROGGED TO BACK WEST TO NEAR I29 THIS
MORNING...AND THEN INCREASE AGAIN DURING THE AFTERNOON FROM THE
WEST. SO WILL LIKELY SEE MORE SUNSHINE EAST OF I29 TODAY WHILE
WESTERN CWA REMAINS MOSTLY CLOUDY. HOW FAR WEST ANY CLEARING GETS
TODAY IS AN ISSUE. AS FAR WEST AS I29 MAY BE OPTIMISTIC BASED ON
CURRENT TRENDS MOST AREAS WILL LIKELY STAY MOSTLY CLOUDY THROUGH THE
DAY WITH SOME CLEARING DURING THE NIGHT. WILL BE ANOTHER COLD DAY
WITH HIGHS ONLY IN THE UPPER 30S TO MID 40S.
FOCUS THEN SHIFTS TO SATURDAY AND WAVE DROPS SOUTHEAST IN NORTHWEST
FLOW ALOFT. ASSOCIATED WEAK INVERTED TROF MOVES INTO WESTERN CWA
SATURDAY AND THEN WEAKENS SATURDAY NIGHT. AM EXPECTING SOME LIGHT
PRECIPITATION TO DEVELOP ACROSS WESTERN CWA SATURDAY IN THE FORM OF
LIGHT RAIN OR LIGHT SNOW. THIS PRECIPITATION MAY HAVE A HARD TIME
GETTING MUCH FURTHER EAST OF I29 SATURDAY NIGHT AS SOMEWHAT OF A
KEEWATIN HIGH KEEPS LOWER LEVELS DRY TO THE EAST OF I29 AND THUS
WILL BE HARD TO SATURATE LOW LEVELS AS WEAK WAVE MOVES EAST OF I29
LATER SATURDAY NIGHT. SO WILL KEEP HIGHEST PRECIPITATION CHANCES
WEST OF I29 SATURDAY NIGHT WITH ONLY A CHANCE OF LIGHT SNOW TO THE
EAST. COULD SEE AN INCH OR SO OF SNOW WEST OF I29 SATURDAY LIGHT
WITH PERHAPS LITTLE IF ANY SNOW TO THE EAST. WITH INCREASING CLOUD
COVER AND LOW LEVEL COLD SOUTHEAST FLOW...HIGH TEMPERATURES WILL
STRUGGLE TO CLIMB THROUGH THE 40S...ALTHOUGH HIGHS COLD TOP NEAR 50
ALONG THE MISSOURI RIVER.
AS SYSTEM PULLS AWAY...CWA IS LEFT IN LOW LEVEL SOUTHEAST FLOW AND
CLOUD COVER ON SUNDAY MAY BE HARD TO CLEAR AS STRATUS MAY BE FAIRLY
WIDESPREAD AGAIN. DRIER AIR DOES MOVE INTO WESTERN CWA DURING THE
DAY...BUT THE QUESTION IS IF THIS WILL BE ENOUGH TO SCOUR OUT LOWER
CLOUDS. FOR NOW WILL BE A LITTLE MORE PESSIMISTIC AND ONLY HAVE
SKIES BECOME PARTLY CLOUDY ACROSS THE WEST. TEMPERATURES WILL REMAIN
COLD WITH HIGHS AGAIN ONLY IN THE 40S MOST PLACES.
BELOW NORMAL TEMPERATURES WILL PERSIST ON MONDAY WITH BLOCKING
PATTERN OFF EAST COAST KEEPS COOLER AIR FUNNELING SOUTHEAST ACROSS
CWA.
TUESDAY AND WEDNESDAY SHOULD BE A BIT WARMER...BUT THAT WILL BE
DEPENDENT ON HOW STORM OFF EAST COAST EVOLVES. WITH RETROGRADING
LOW...COOLER TEMPERATURES LIKELY TO REMAIN IN PLACE ACROSS THE CWA
AND NOT AS PROGRESSIVE EAST AS MODEL MAY INDICATE. SO NOT
SIGNIFICANTLY WARMER MONDAY TUESDAY THROUGH THURSDAY. WILL LEAVE
FORECAST DRY AFTER SATURDAY NIGHT...BUT A WEAK WAVE DROPPING
SOUTHEAST TUESDAY COULD PRODUCE SOME LIGHT RAIN...MAINLY OVER
WESTERN CWA AS HIGH PRESSURE OVER THE WESTERN GREAT LAKES REGION
BLOCKS PROGRESSION FURTHER EAST.
&&
.AVIATION.../FOR THE 12Z TAF ISSUANCE/
MAINLY VFR CONDITIONS EXPECTED THROUGH THE PERIOD. CLOUD DECK IS
HOLDING STRONG ACROSS THE AREA AND IS NOT BEING HANDLED WELL BY MOST
MODELS. THE RAP IS THE ONLY GUIDANCE THAT HAS THE CLOUD DECK...AND
IT KEEPS THE CLOUDS AROUND THROUGH THE DAY. THIS SEEMS
REASONABLE...AS EVEN THE NAM AND GFS SUGGEST CLOUDS WOULD REFORM AS
MIXING COMMENCED LATER THIS MORNING. THUS WILL KEEP CLOUDS IN
THROUGH THE DAY AND INTO THIS EVENING. THINK CIGS IN THESE CLOUDS
WILL STAY VFR AROUND 4K FEET...ALTHOUGH SOME ISOLATED MARGINAL MVFR
IS POSSIBLE THIS MORNING AND THEN AGAIN THIS EVENING. AS WE LOSE THE
NORTHWESTERLY FLOW AND WINDS GO CALM OR LIGHT SOUTHERLY
TONIGHT...THINK CLOUD DECK SHOULD FINALLY DISSIPATE. THIS COULD
ALLOW FOR SOME FOG FORMATION WITH MOIST LOW LEVELS REMAINING.
HOWEVER CURRENTLY THINK AN INCREASE IN HIGH CLOUDS MIGHT PREVENT
THIS...SO WILL LEAVE FOG OUT OF THE TAF FOR NOW. /CHENARD
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
547 AM CDT FRI OCT 26 2012
.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
301 AM CDT FRI OCT 26 2012
MAIN FORECAST CONCERNS ARE ON SKY COVER TODAY AND TEMPERATURES
THROUGHOUT.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING OVER THE EASTERN PACIFIC...TROUGHING OVER THE WESTERN
TWO THIRDS OF CANADA SOUTHWARD INTO THE CENTRAL PLAINS...RIDGING
ALONG THE EAST COAST INTO QUEBEC AND HURRICANE SANDY IN THE
NORTHWEST BAHAMAS. THE FORECAST AREA RESIDES IN THE WAKE OF A STRUNG
OUT SHORTWAVE FROM IOWA INTO EASTERN LAKE SUPERIOR...PROVIDING FOR
SUBSIDENCE AND DRYING ALOFT SEEN ON 00Z SOUNDINGS FROM MPX...ABR AND
BIS. THESE SAME SOUNDINGS SHOW A COLD FRONTAL/SUBSIDENCE INVERSION
AROUND 800MB WITH ABOUT A 50-75MB LAYER OF NEAR SATURATION BELOW IT.
THIS SATURATION WAS REFLECTED BY THE LARGE AMOUNT OF STRATUS
ENCOMPASSING THE NORTHERN PLAINS INTO THE UPPER MISSISSIPPI RIVER
VALLEY REGION LAST EVENING. HOWEVER...DURING THE LAST TWO HOURS A
LARGE AREA OF CLEARING HAS DEVELOPED ACROSS THE FORECAST AREA.
850MB TEMPS HAVE DROPPED CONSIDERABLY WITH THE 00Z MPX SOUNDING
REPORTING -7C...COMPARED TO 2C AT 12Z AND 9C 24 HOURS EARLIER. THIS
COLD AIR HAS BEEN RUSHING IN ON A STILL BREEZY NORTHWEST WIND...
CAUSED BY A TIGHT PRESSURE GRADIENT BETWEEN HIGH PRESSURE IN WESTERN
NEBRASKA AND LOW PRESSURE IN HUDSON BAY. THE WIND HAS KEPT
TEMPERATURES FROM TANKING WITH READINGS MAINLY IN THE 30S.
TODAY THROUGH SATURDAY...26.00Z MODEL GUIDANCE IS IN VERY GOOD
AGREEMENT THAT THE UPPER TROUGH AND ITS AXIS THROUGH THE CENTRAL
PLAINS STAYS NEARLY STATIONARY OR JUST SLOWLY SHIFTS EAST. THIS IS
MOSTLY DUE TO THE BLOCKING AHEAD OF IT...PRODUCED BY THE HIGHLY
AMPLIFIED RIDGING BUILDING UP THROUGH THE CANADIAN MARITIMES AND
HURRICANE SANDY PARALLELING THE SOUTHEAST U.S. COASTLINE. WITH
LITTLE MOVEMENT IN THE UPPER TROUGH...IT WILL BE VERY TOUGH TO GET
ANY PRECIPITATION PRODUCTION...OR WARM ADVECTION FOR THAT MATTER.
HOWEVER...THE HIGH PRESSURE AREA IN NEBRASKA IS PROGGED TO SHIFT
NORTHEAST INTO THE FORECAST AREA FOR LATE TONIGHT AND SATURDAY...
WHICH WILL ALLOW WINDS TO GRADUALLY DIMINISH. BIGGEST ISSUE IS SKY
COVER. WITH THE RECENT CLEARING THAT HAS OCCURRED...WENT WITH A MORE
OPTIMISTIC SCENARIO THAN WHAT THE PAST FEW RUNS OF THE RAP HAVE
SUGGESTED. IDEA HERE IS NOW THAT THE COMBINATION OF DIURNAL
HEATING...LINGERING SURFACE MOISTURE AND COOL AIR ALOFT SHOULD ALLOW
FOR SOME STRATOCUMULUS TO REDEVELOP. DIURNAL COOLING TONIGHT AND THE
HIGH PRESSURE AREA BUILDING IN WILL RESULT IN CLEARING SKIES. A GOOD
AMOUNT OF CIRRUS IS PROGGED TO ADVECT IN FROM THE NORTHWEST ON
SATURDAY...AHEAD OF A SHORTWAVE DROPPING INTO THE TROUGH OVER
NEBRASKA. WITH 850MB TEMPS OF -4 TO -8C BOTH TODAY AND
SATURDAY...TEMPERATURES WILL STRUGGLE TO GET MUCH ABOVE THE LOW TO
MID 40S. THE CLEARING SKIES TONIGHT AND THE COOL AIR IN PLACE SHOULD
EASILY ALLOW TEMPERATURES TO FALL INTO THE 20S...WHILE THE TYPICAL
COLD SPOTS COULD EVEN DROP INTO THE UPPER TEENS.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...THE SHORTWAVE MENTIONED ON
SATURDAY DROPPING INTO NEBRASKA WILL BE A NOTABLE FEATURE...
ESPECIALLY FOR BEING ABLE TO PICK UP SANDY AND HELP CURVE IT BACK
TOWARDS THE MID-ATLANTIC/NORTHEAST EARLY NEXT WEEK. FOR US...THE
SHORTWAVE DIGS DOWN INTO THE TENNESSEE VALLEY BY SUNDAY. ANY
PRECIPITATION ASSOCIATED WITH THIS SHORTWAVE LOOKS TO STAY SOUTH AND
WEST OF THE AREA...WHILE THE HIGH PRESSURE AREA REMAINS NEARLY
STATIONARY. THIS HOLDS TRUE RIGHT THROUGH SUNDAY NIGHT. WITH UPPER
TROUGHING AND HIGH PRESSURE STILL IN PLACE...850MB TEMPS ARE GOING
TO STRUGGLE TO CLIMB...WITH MAYBE A 1-2C RISE OFF OF SATURDAY.
THUS...ANTICIPATING SUNDAYS HIGHS TO BE SIMILAR TO SATURDAY...IN
THE LOW TO MID 40S. SOME CIRRUS AND PERHAPS EVEN MID CLOUD COVER ON
SATURDAY NIGHT SHOULD RESULT IN A SLIGHTLY WARMER NIGHT COMPARED TO
TONIGHT. SAME HOLDS TRUE FOR SUNDAY NIGHT WITH YET ANOTHER AREA OF
CIRRUS PROGGED TO DROP IN FROM THE NORTHWEST.
.LONG TERM...MONDAY THROUGH THURSDAY NIGHT
301 AM CDT FRI OCT 26 2012
26.00Z ECMWF/GFS/CANADIAN/UKMET AND GFS ENSEMBLES ARE ALL IN GOOD
AGREEMENT OF SHOWING A BLOCKED UP UPPER LEVEL PATTERN ACROSS NORTH
AMERICA NEXT WEEK. A LOT OF THIS BLOCKING IS DUE TO SUBTROPICAL
RIDGING STUCK OVER NEWFOUNDLAND...ALLOWING HURRICANE SANDY TO
PHASE WITH THE CURRENT UPPER TROUGH OVER THE CENTRAL PLAINS.
ALTHOUGH THERE ARE CERTAINLY PLENTY OF DETAIL DIFFERENCES ABOUT
THE POST-TROPICAL STATE AND TRACK OF HURRICANE SANDY...OUR AREA
STAYS ON THE WEST/SUBSIDENT SIDE OF THE PHASED SYSTEM. THIS SHOULD
MAINTAIN A RIDGE OF HIGH PRESSURE AT THE SURFACE NEAR OR JUST WEST
OF THE AREA...ALONG WITH DRY WEATHER. NOTE THAT THE 26.00Z ECMWF
DOES SHOW A LITTLE MORE WESTWARD TRACK OF POST-TROPICAL SANDY...
WHICH RESULTS IN A BREEZY TUESDAY AND TUESDAY NIGHT PERIOD. THE
MODEL IS EVEN SUGGESTING THE DEFORMATION BAND COULD GET CLOSE TO
CENTRAL WISCONSIN ON WEDNESDAY. THERE ARE HINTS TOWARDS THURSDAY
NIGHT OF UPPER RIDGING BUILDING OVER THE WESTERN U.S. GETTING
PUSHED EAST TOWARDS THE AREA...THOUGH PLENTY OF UNCERTAINTY EXISTS
ON THIS GIVEN THE ISSUES WITH THE EJECTION OF POST-TROPICAL SANDY.
850MB TEMPS WILL SLOWLY WARM THROUGH NEXT WEEK...WITH MOST AREAS
SEEING READINGS OF 0C OR HIGHER BY WEDNESDAY. THUS...ANTICIPATE A
GENERAL WARMING TREND. FOLLOWED A CONSENSUS SOLUTION FOR
TEMPERATURES.
&&
.AVIATION...TODAY AND TONIGHT
547 AM CDT FRI OCT 26 2012
MAIN CONCERN WILL BE WINDS AND CLOUDS TODAY. SURFACE HIGH PRESSURE
WILL CONTINUE TO BUILD INTO THE AREA FROM THE PLAINS TODAY.
HOWEVER...A STEEPENING TEMPERATURE LAPSE RATE ASSOCIATED WITH
LINGERING COLD/CYCLONIC FLOW ALOFT EXPECTED TO PRODUCE SCATTERED
CUMULUS/STRATOCUMULUS WITH BASES AOA 3500 FEET AGL. SOMEWHAT
BREEZY CONDITIONS WILL ALSO BE SEEN WITH WINDS FROM THE WEST-
NORTHWEST IN THE 10-15KT RANGE WITH GUSTS AROUND 20KT. HIGH
PRESSURE WILL THEN BUILD OVER THE AREA TONIGHT FOR CLEARING SKIES
AND LIGHT WINDS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
301 AM CDT FRI OCT 26 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
137 PM EDT FRI OCT 26 2012
.AVIATION...
18Z TAFS...THIN LAYER OF SATURATION SHOULD GRADUALLY GIVE WAY TO
VERY DRY LOW LEVEL AIR MOVING IN FROM THE NORTHWEST TO AT LEAST
IMPROVE CIGS TO VFR BY THE 19Z-20Z TIME FRAME. SOME LAKE EFFECT
STRATOCU NOW EVIDENT ON VIS IMAGERY...BUT WITH LOW INVERSION
HEIGHTS AND LIMITED LAKE INDUCED INSTABILITY...THESE CLOUDS ARE
NOT EXPECTED TO HAVE A LARGE IMPACT AT KSBN. THE OTHER THING TO
WATCH FOR THIS AFTERNOON WILL BE THE POTENTIAL FOR ANY LIGHT
SHOWERS TO AFFECT KFWA. SOME REDEVELOPMENT OF POST FRONTAL RAIN
NOW NOTED ACROSS SOUTHEAST INDIANA AND THE TREND SHOULD BE FOR
EXPANSION OF THIS AREA INTO FAR NORTHEAST INDIANA. IT APPEARS AS
THOUGH BETTER CHANCE OF -RA WILL AFFECT AREAS SOUTHEAST OF KFWA
AND WILL KEEP TERMINAL DRY. OTHERWISE...VFR CONDITIONS THROUGH THE
REMAINDER OF THE PERIOD WITH LAKE EFFECT STRATOCU AFFECTING AREAS
WEST OF KSBN.
&&
.PREV DISCUSSION... /ISSUED 1039 AM EDT FRI OCT 26 2012/
UPDATE...
BAND OF SHOWERS CONTINUES TO SHIFT EASTWARD ACROSS NW OHIO
COUNTIES THIS MORNING IN ASSOCIATION WITH LOW LEVEL FRONTAL ZONE
AND A WEAK SHORT WAVE LIFTING NORTHEAST OUT OF SOUTHEAST INDIANA.
LAGGING 800:700 HPA FRONTAL ZONE WILL BE VERY SLOW TO TRACK
ACROSS SOUTHEAST PORTIONS OF THE AREA THIS AFTERNOON. IN
ADDITION...WATER VAPOR IMAGERY SHOWING A FAIRLY PRONOUNCED
UPSTREAM TROUGH ACROSS THE CENTRAL PLAINS WITH 14Z RAP INITIALIZING
A SHEARED VORTICITY MAXIMUM FROM NORTHERN MISSOURI INTO NORTHWEST
ILLINOIS PRECEDING THIS SHORT WAVE. AS MID/UPPER LEVEL TROUGH AXIS
ACROSS THE PLAINS SHIFTS EASTWARD TODAY...WOULD SUSPECT THAT
RENEWED LIGHT SHOWER DEVELOPMENT WILL BE POSSIBLE ALONG LAGGING
MID LEVEL BAROCLINIC ZONE ACROSS PRIMARILY SOUTHEAST PORTIONS OF
THE FORECAST AREA. HOWEVER...GIVEN TIMING OF AFOREMENTIONED MID
LEVEL FORCING...THIS ENHANCEMENT MAY NOT OCCUR UNTIL THE EVENING.
STARTING TO SEE SOME LIGHT RETURNS BEHIND THE INITIAL RAIN BAND
ACROSS SOUTHERN ILLINOIS AND WILL NEED TO WATCH TRENDS NORTHEAST
AND HOW THIS FILLS IN ALONG THE MID LEVEL FRONT THIS AFTERNOON.
HAVE OPTED TO STAY CLOSE TO PREVIOUS FORECAST AND JUST SHAVE POPS
SLIGHTLY ACROSS THE WESTERN EXTENT WHERE LOW LEVEL MOISTURE
AVAILABILITY BECOMES MORE IN QUESTION. NO CHANGE TO OTHER FORECAST
ELEMENTS ALTHOUGH RAOB/TAMDAR DATA SUGGESTS LOW LEVEL INVERSION
MAY BE A BIT STRONGER THAN MODEL DEPICTION...AND THUS LOW CLOUDS
MAY LINGER A BIT LONGER. HOWEVER...MAGNITUDE OF DRY AIR ADVECTION
LATER TODAY SHOULD TEND TO OVERWHELM INFLUENCES OF LOW LEVEL
INVERSION ALLOWING FOR AT LEAST PARTIAL SUNSHINE ACROSS AT LEAST MOST
OF WESTERN PORTIONS OF THE AREA. UPDATE FORECAST SENT EARLIER THIS
MORNING TO REFRESH EARLY MORNING WORDING AND TO ACCOUNT FOR
MORNING POP TRENDS.
PREV DISCUSSION... /ISSUED 342 AM EDT FRI OCT 26 2012/
SHORT TERM...TODAY THROUGH SATURDAY NIGHT
STRONG SFC COLD FRONT WILL CLEAR OUR NW OH COUNTIES BY DAYBREAK WITH
TEMPS IN THE MID/UPPER 60S QUICKLY FALLING INTO THE 50S/40S.
TEMPS HAVE ALREADY DROPPED INTO THE 40S ACROSS OUR WESTERN ZONES
WITH LITTLE RECOVERY ANTICIPATED TODAY IN STRONG CAA REGIME...WITH
HIGHS NEARLY 30F COOLER THAN YESTERDAY. POST FRONTAL BAND OF RAIN
SHOWERS ORIENTED NW TO SW (NEARLY 50 MILES WIDE) WILL SLIDE EAST
THROUGH THE AREA TODAY...WITH OUR NW INDIANA AND SW LOWER MI
COUNTIES LIKELY SEEING A MAINLY DRY DAY AS RAIN BAND EXITS EAST
AROUND OR JUST AFTER DAYBREAK. THIS BAND OF RAIN IS SET UP IN
TYPICAL ANAFRONT FASHION, GETTING A BOOST FROM A WESTERN/NORTHERN
GREAT LAKES ~120 KT UPPER LEVEL JET IN ADVANCE OF A CENTRAL CONUS
UPPER TROUGH. THERE MAY BE A LULL IN SHOWER INTENSITY/COVERAGE FOR A
PERIOD TODAY AS THE FRONTAL SCALE CIRCULATION WEAKENS. THIS LULL WILL
BE BRIEF AS A MID LVL SHORTWAVE OVER THE CENTRAL HIGH PLAINS/ROCKIES
EJECTS NE INTO THE GREAT LAKES/OH VALLEY LATER TODAY INTO TONIGHT.
THE RESULTING MID LVL FRONTOGENETIC RESPONSE WILL LIKELY AID IN AN
INCREASE IN SHOWER COVERAGE DURING THIS TIME. HOWEVER...DRIER AIR
WILL HAVE WORKED INTO MOST OF OUR IN/MI COUNTIES BY THIS TIME WITH
THE BEST CHANCE FOR RAINFALL ALONG THE STALLING BAROCLINIC ZONE
ACROSS OUR FAR SOUTHEAST INTO CENTRAL OHIO (BEST CHANCES JAY COUNTY
INDIANA NE INTO VAN WERT/PUTNAM/ALLEN COUNTIES IN OHIO). RAINFALL
AMOUNTS GREATER THAN A HALF AN INCH WILL BE POSSIBLE HERE WITH
LIGHTER AMOUNTS CLOSER TO A QUARTER OF AN INCH ELSEWHERE.
OTHERWISE...COOL/DRY NORTHERLY FLOW IS STILL EXPECTED SATURDAY INTO
SATURDAY NIGHT WITH ONLY MINOR TWEAKS MADE.
LONG TERM.../SUN-THU/
GFS CONTS TO INDICATE TRACK OF HURRICANE SANDY WILL BE TO THE
RIGHT/EAST OF ECMWF`S FCST. ECMWF HAS BEEN MOST CONSISTENT OF THE
MEDIUM RANGE MODELS BUT CONSIDERABLE VARIABILITY ON TRACK CONTS FROM
RUN-RUN... ESPECIALLY FROM GFS/GEM. FOR SUN/SUN NGT LEANED TOWARD A
00Z GFS/12Z ECMWF COMPROMISE FOR FCST DETAILS AS NAM WAS AN OUTLIER
INDICATING MUCH FASTER NORTHERLY MOVEMENT OF THE WRN ATLANTIC
HURRICANE WHILE GEM WAS A FAR RIGHT TRACK OUTLIER. THUS... UPR LEVEL
TROF EXPECTED TO MOVE ACROSS THE GRTLKS SUN/SUN NGT WITH SFC RIDGE
OVER THE UPR MS VALLEY REMAINING NEARLY STNRY AS HURRICANE SANDY
MOVES NORTHWARD OFF THE EAST COAST. THIS SCENARIO SHOULD RESULT IN
DRY WX WITH BLO NORMAL TEMPS AND MODEST NORTHERLY GRADIENT FLOW
ACROSS OUR AREA FOR THE END OF THE WEEKEND.
SANDY IS EXPECTED TO CURVE NWWD MONDAY AND MOVE INLAND OVER THE
MID-ATLANTIC STATES TUE... WITH EXTRA-TROPICAL LOW THEN SLOWLY
CURVING BACK NE INTO SRN QUEBEC BY THU EVE. GIVEN THIS TRACK...
STILL APPEARS AS IF WRN EDGE OF PRECIP SHIELD ASSOCIATED WITH THIS
LOW WILL BE OVER OR JUST EAST OF OUR CWA. ALSO CONTS TO BE A CHC FOR
SOME LAKE EFFECT SHOWERS NEAR LAKE MICHIGAN MID-WEEK WITH NNW LOW
LEVEL FLOW AND DELTA T`S IN THE TEENS. THUS POPS GENERALLY RAMPED UP
A NOTCH THROUGH THIS PERIOD. TEMP PROFILES CONTG TO SUGGEST IT
COULD BE COLD ENOUGH AT TIMES FOR THE PRECIP IF IT OCCURS TO FALL AS
SNOW... MAINLY DURING THE OVERNIGHT HOURS.
HIGH TEMPS EXPECTED TO RANGE FROM 45-50 SUNDAY... GRDLY LOWERING TO
THE M40S ACROSS THE AREA BY TUE-WED WHICH SHOULD BE THE CLOUDIEST
DAYS OF THE PERIOD... AND THEN SLOWLY MODERATING BACK TO NEAR 50 BY
THU AS THE LOW PULLS AWAY. LOWS EXPECTED TO BE IN THE L-M30S THROUGH
THE PERIOD.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 5 AM EDT SUNDAY FOR LMZ043-046.
&&
$$
SHORT TERM...STEINWEDEL
LONG TERM...JT
UPDATE...MARSILI
AVIATION...MARSILI
AREA FORECAST DISCUSSION
NWS DES MOINES IA
342 PM CDT FRI OCT 26 2012
.SHORT TERM /TONIGHT/...
HIGH PRESSURE CURRENTLY CENTERED OVER SW NE AND NW KS WILL TRANSLATE
EASTWARD TONIGHT. THIS WILL ALLOW WINDS TO DIMINISH WITH SUNSET.
STRATUS DECK THAT HAS BEEN IN PLACE MUCH OF THE DAY HAS BECOME MORE
CELLULAR ON THE SOUTH/EASTERN EDGES AND EXPECT THAT AREA AND POINTS
FURTHER SOUTH/EAST IN THE CWA TO CLEAR OFF OVERNIGHT. MODELS HAVE
BEEN HAVING A HARD TIME DEALING WITH THIS LOWER LEVEL MOISTURE THAT
IS TRAPPED BELOW THE INVERSION. THEREFORE TEMPERATURES A BIT TRICKY
TONIGHT DUE TO UNCERTAINTY WITH THE CLOUD COVER. RAP MODEL SEEMED TO
BE LINING UP THE BEST WITH ITS 925-850MB RH FIELD...THEREFORE
TRENDED SKY COVER TOWARD THAT MODEL. THIS SOLUTION ALSO SUGGESTS THE
CLEARING IN THE AFOREMENTIONED AREAS AND THE LOWER CLOUDS LINGERING
ACROSS THE WEST CENTRAL/NORTHWESTERN CWA THROUGH THE NIGHT.
THEREFORE HAVE KEPT TEMPS A LITTLE WARMER DUE TO THE CLOUD
COVER...BUT STILL A LITTLE COOLER FROM READINGS LAST NIGHT DUE TO
THE UNCERTAINTY WITH THE CLOUD COVER.
.LONG TERM /SATURDAY THROUGH FRIDAY/...
WITH ALL EYES ON THE EAST COAST AND EVOLUTION OF SANDY...IA WEATHER
WILL BE TRANQUIL WITH SEASONALLY COOL TEMPERATURES. ONLY NEAR TERM
WINDOW FOR PRECIP WILL BE WITH SHORT WAVE CURRENTLY OFF BC COAST
WHICH DROPS INTO MO VALLEY SAT NIGHT. MODELS HAVE TRENDED SLIGHTLY
NORTH AND WEST WITH ITS FORCING AND MOISTURE SO HAVE REMOVED
MEASURABLE POPS WITH NOTHING BEYOND FLURRY WORDING FAR NW 09-15Z SAT.
A SIMILAR SHORT WAVE EJECTING OUT OF THE PACIFIC NW THIS WEEKEND
WILL DROP INTO THE BASE OF THE MS/OH VALLEY LONG WAVE TROUGH AND
EVENTUALLY PHASE WITH SANDY. THIS IMPRESSIVE STORM...WHERE EVER ITS
LOCATION AND LANDFALL...WILL BE SLOW MOVING AND LOCK IN OUR PATTERN
KEEPING IA IN PERSISTENT RELATIVELY DRY NW FLOW AND NEAR NORMAL
TEMPERATURES. ALTHOUGH CONFIDENCE AND MODEL CONSENSUS IS NOT GREAT
ENOUGH TO INTRODUCE MEASURABLE POPS AT THIS POINT...TOKEN PRECIP
MENTION MAY EVENTUALLY BE NEEDED AROUND MON OR TUE...AND AGAIN
AROUND THU. TEMPERATURES WILL BE FAIRLY STEADY THROUGH THE ENTIRE
PERIOD WITH GENERALLY LIGHT WINDS AND LITTLE CHANGE IN AIRMASS.
&&
.AVIATION...26/18Z
LOW VFR STRATUS DECK EXPECTED TO SLOWLY EXPAND TO THE EAST AND
REMAIN IN PLACE MUCH OF THE FORECAST PERIOD...WILL MAINLY IMPACT
KDSM...KFOD...AND KMCW. SOME GUSTINESS WITH THE NORTHWEST WINDS
THROUGH EARLY EVENING...THEN WINDS EXPECTED TO DIMINISH OVERNIGHT.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM/AVIATION...BEERENDS
LONG TERM...SMALL
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
324 PM CDT FRI OCT 26 2012
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 302 PM CDT FRI OCT 26 2012
A FAST MOVING SHORTWAVE TROUGH WAS OVER EASTERN COLORADO AND WESTERN
KANSAS THIS MORNING. THIS SYSTEM BROUGHT SOME MEASURABLE SNOW TO FAR
WESTERN PORTIONS OF SOUTHWEST KANSAS. BY EARLY AFTERNOON THE
SHORTWAVE HAD MOVED INTO EASTERN KANSAS WITH CLEARING SKIES IN ITS
WAKE. THERE WAS SOME LINGERING STRATUS ALONG WITH LIGHT SNOW
FLURRIES OUT ALONG THE COLORADO BORDER BEING FORCED BY SOME WEAK PVA
AND LOW LEVEL UPSLOPE. RUC13 MODEL CROSS SECTIONS SHOW THIS AREA OF
CLOUDS/PRECIPITATION DECREASING THROUGH THE NEXT FEW HOURS. VISIBLE
SATELLITE LOOPS SHOW THE AREA OF STRATUS ALREADY STARTING TO
DIMINISH. SKIES SHOULD BE MOSTLY CLEAR ACROSS ALL OF SOUTHWEST
KANSAS BY THIS EVENING.
WITH THE COLD HIGH PRESSURE AIRMASS IN PLACE ACROSS WESTERN KANSAS,
CLEAR SKIES AND LIGHT WINDS THIS EVENING WILL RESULT IN TEMPERATURES
FALLING TO BELOW FREEZING FAIRLY SOON AFTER SUNSET. OVERNIGHT LOWS
WILL BE FALLING INTO THE LOWER TO MIDDLE 20S ACROSS THE ENTIRE AREA
OVERNIGHT. WITH THIS IN MIND, WILL CONVERT THE HARD FREEZE WATCH TO
A HARD FREEZE WARNING FOR THE AREA ALONG AND SOUTH OF A LINE FROM
JOHNSON TO JETMORE AND LARNED. THE AREA FROM SYRACUSE THROUGH
DIGHTON SAW A GOOD FREEZE LAST NIGHT SO THEY ARE DONE FOR THE YEAR
AS ARE AREAS UP TOWARD I-70. ANOTHER WEAK AND FAST MOVING SHORTWAVE
TROUGH WILL BE APPROACHING THE CENTRAL HIGH PLAINS LATER TONIGHT.
THIS COULD SPREAD SOME HIGH CLOUDINESS INTO PARTS OF WESTERN KANSAS.
IN ADDITION, THE SURFACE HIGH PRESSURE WILL BE MOVING INTO EASTERN
KANSAS LATER TONIGHT WHILE PRESSURE FALLS WILL ENSUE ALONG THE
EASTERN SLOPES OF THE ROCKIES. THIS COULD RESULT IN TEMPERATURES
RISING SOMEWHAT LATE TONIGHT.
SOUTHERLY WINDS WILL BECOME GUSTY FROM THE SOUTH ON SATURDAY AS THE
SURFACE PRESSURE GRADIENT INCREASES. ONLY SOME SCATTERED HIGH
CLOUDINESS IS EXPECTED DURING THE DAY. BASED ON MODEL 850
TEMPERATURE FORECASTS, HIGHS ON SATURDAY SHOULD ONLY CLIMB INTO THE
LOWER 50S IN MOST AREAS.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 321 PM CDT FRI OCT 26 2012
SOUTHERLY WINDS WILL BECOME ESTABLISHED BY OVERNIGHT SATURDAY, BUT
TEMPERATURES WILL LIKELY STILL FALL TO AROUND FREEZING WITH LIGHT
WINDS AND SUCH A DRY AIRMASS. THE ECMWF AND GFS ARE VERY SIMILAR IN
THE GENERAL MASS FIELDS FOR SUNDAY. SIMILARITIES ARE MOST
PRONOUNCED IN THE MID LEVEL RELATIVE HUMIDITY FIELDS, ASSOCIATED
WITH REMNANTS OF A NORTHERN PLAINS SHORTWAVE AND THE UPPER JET
DIVING THROUGH THE GREAT PLAINS FROM NORTH TO SOUTH. THIS COULD LEAD
TO CONSIDERABLE ALTOSTRATUS OR AT LEAST HIGH CIRRUS CLOUDS FOR
CENTRAL KANSAS FOR A GOOD PORTION OF THE DAY. THERMAL FIELDS DIFFER
CONSIDERABLE HOWEVER, ESPECIALLY WITH RESPECT TO HOW FAST THE GFS
WARMS THE BOUNDARY LAYER APPROXIMATED BY 850 MB TEMPERATURES. GFS IS
GENERALLY MUCH WARMER WHICH REFLECTS IN MODEL`S AFTERNOON HIGHS.
GIVEN HOW MUCH OF A WARM BIAS SEVERAL FORECAST DAYS HAVE BEEN
RECENTLY, WE`LL FOLLOW THE COOLER ECMWF IDEA, BUT USE GFS MOS
TEMPERATURES THAT ARE COOLER IN THE WEST.
A DRY PATTERN WILL BE ESTABLISHED THROUGH THE REMAINDER OF THE WEEK.
THE SYNOPTIC PATTERN INCLUDES A WEDGE OF RELATIVE SURFACE HIGH
PRESSURE ANCHORED FROM THE UPPER MIDWEST...SOUTHWEST ACROSS THE MID
MISSISSIPPI VALLEY INTO NORTHEAST TEXAS. WITH THE EXPECTED HURRICANE
OR TROPICAL STORM SPREADING WESTWARD INTO THE EASTERN TROUGH. THAT
PATTERN WILL MAINTAIN THE UPPER RIDGE FROM TUESDAY INTO THURSDAY
RIGHT OVER THE HIGH PLAINS REGIONS. LIGHT SOUTHERLY SURFACE WINDS
WILL BE THE PREVAILING WIND DIRECTION. HIGHS WILL INCREASE THROUGH
THE 60S, AND REACH THE LOW 70S WEDNESDAY OR THURSDAY. HIGHER
SURFACE DEW POINT INCREASING BACK INTO THE 30S WILL BRING OVERNIGHT
LOWS BACK ABOVE FREEZING THROUGH THE PERIOD AS WELL. BY FRIDAY, THE
UPPER FLOW BECOMES STRONGLY DIVERGENT ACROSS THE REGION AS A SHARP
TROUGH MOVES ACROSS THE WESTERN STATES, WHICH IS MODELED BY BOTH THE
GFS AND ECMWF. IN EITHER INSTANCE, THE WEATHER TYPE FOR THE REGION
APPEARS TO BE PRIMARILY WET - SHOWERS OR THUNDERSTORMS, BUT THE
MESOSCALE DETAILS ARE HIGHLY UNCERTAIN AT THIS TIME, AND COULD MISS
WESTERN KANSAS ALTOGETHER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1228 PM CDT FRI OCT 26 2012
MVFR CEILINGS ARE RAPIDLY ERODING ACROSS WEST CENTRAL AND SOUTHWEST
KANSAS LATE THIS MORNING. ALL THE TAF SITES SHOULD BE VFR AT THE
BEGINNING OF THIS TAF PERIOD. SOME LINGERING AREAS OF LOW CEILINGS
WEST OF GARDEN CITY AND SOUTH OF HAYS SHOULD BE DISSIPATING BY 21Z.
VFR CONDITIONS ALONG WITH LIGHT AND VARIABLE WINDS WILL PREVAIL THROUGH
12Z SATURDAY. ON SATURDAY, SURFACE HIGH PRESSURE WILL MOVE INTO EASTERN
KANSAS WHILE PRESSURES START TO LOWER IN THE LEE SLOPES OF THE ROCKIES.
SOUTHERLY WINDS WILL INCREASE INTO THE 10 TO 20 KNOT RANGE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 22 52 30 59 / 0 0 0 0
GCK 24 52 29 59 / 0 0 0 0
EHA 25 54 31 59 / 0 0 0 0
LBL 23 54 30 61 / 0 0 0 0
HYS 22 50 28 57 / 0 0 0 0
P28 23 52 29 59 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
HARD FREEZE WARNING FROM 10 PM THIS EVENING TO 9 AM CDT SATURDAY
FOR KSZ064>066-074>081-084>090.
&&
$$
SHORT TERM...GERARD
LONG TERM...RUSSELL
AVIATION...GERARD
AREA FORECAST DISCUSSION
NWS TOPEKA KS
322 PM CDT FRI OCT 26 2012
.DISCUSSION...
SHORT TERM FORECAST - TONIGHT AND SATURDAY...
AT 19Z RAP SURFACE ANALYSIS INDICATED A RIDGE OF HIGH PRESSURE
LOCATED ROUGHLY ACROSS WESTERN NEBRASKA AND WESTERN KANSAS...WITH
THE RIDGE AXIS RUNNING FROM KBBW SOUTHWESTWARD TO KGLD. ALONG THE
EASTERN EDGE OF THE AREA OF HIGH PRESSURE NORTHERLY WINDS CONTINUE
TO ALLOW COOLER AIR TO TRICKLE INTO EASTERN KANSAS. AS THE RIDGE
MOVES EASTWARD THE AXIS WILL BECOME CENTERED OVER THE FORECAST AREA
TONIGHT...WHICH WILL CAUSE WINDS TO BECOME CALM AND SKIES TO BECOME
MOSTLY CLEAR TO PARTLY CLOUDY. THE COMBINATION OF THE TWO EFFECTS
WILL BRING VERY CHILLY TEMPERATURES TO THE REGION FOR THE OVERNIGHT
HOURS. EXPECT TEMPS TO DROP INTO THE LOWER TO MID 20S ACROSS THE
ENTIRE AREA...WITH LOW LYING SUCH AS RIVER VALLEYS TO DROP INTO THE
UPPER TEENS TO LOWER 20S. AS THE SURFACE HIGH MOVES TO THE EAST
SOUTHERLY FLOW WILL GRADUALLY PICK UP ON THE BACK/WEST SIDE OF THE
DEPARTING RIDGE...WHICH WILL COMMENCE A SLOW WARM UP TREND...WHICH
WILL CONTINUE THROUGH THE WEEKEND. EXPECT HIGHS ON SATURDAY TO BE
SLIGHTLY WARMER THAN FRIDAY`S HIGHS...BUT WITH HIGH CLOUDS MOVING
THROUGH THE AMOUNT OF WARMING FOR SATURDAY WILL BE MARGINAL...SO
WILL EXPECT HIGHS TO GENERALLY BE IN THE LOWER TO MID 50S.
JL
LONG TERM - SATURDAY NIGHT THROUGH FRIDAY...
THE ENTIRE PERIOD IS FORECAST TO BE TRANQUIL AND ESSENTIALLY
PRECIPITATION FREE. NORTHWEST UPPER LEVEL FLOW WILL PERSIST ACROSS
THE REGION WITH INCREASED UPPER LEVEL RIDGING WITH TIME. MAY SEE
A FEW PERIODS OF INCREASED CLOUD COVER AS A SERIES OF VERY WEAK
DISTURBANCES MOVES THROUGH THE NORTHWEST FLOW BETWEEN NOW AND
WEDNESDAY...BUT NO PRECIPITATION IS EXPECTED WITH THESE SYSTEMS
GIVEN LACK OF MOISTURE AND ONLY WEAK ASCENT. EXPECT A GRADUAL WARM
UP WITH THE INCREASED RIDGING...PARTICULARLY DURING THE SECOND
HALF OF THE WEEK AS MODEL GUIDANCE IS CONSISTENT IN BRINGING A
FAIRLY STRONG SHORT WAVE TROUGH ACROSS THE ROCKIES BY NEXT
WEEKEND. ANY PRECIPITATION ASSOCIATED WITH THIS TROUGH WOULD
LIKELY HOLD OFF UNTIL FRIDAY NIGHT OR LATER...BUT WARMING
TEMPERATURES AND AN INCREASE IN LOW LEVEL MOISTURE IN ADVANCE OF
THE SYSTEM MAY BE NOTICED AS EARLY AS THURSDAY.
BARJENBRUCH
&&
.AVIATION...
VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. THERE HAS BEEN SOME
INTERMITTENT GUSTS REPORTED AT THE TAF SITES LATE THIS MORNING SO
KEPT THE POSSIBILITY OF GUSTS UNTIL SUNSET. THERE MAY BE A BRIEF
PERIOD OR TWO WHEN THE CIGS GO MVFR THIS AFTERNOON AND EVENING BUT
EXPECT MAINLY VFR CONDITIONS. HIGH CLOUDS EVENTUALLY MOVE INTO THE AREA
OVERNIGHT.
SANDERS / LEIGHTON
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
303 PM CDT FRI OCT 26 2012
...UPDATED SHORT TERM DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 302 PM CDT FRI OCT 26 2012
A FAST MOVING SHORTWAVE TROUGH WAS OVER EASTERN COLORADO AND WESTERN
KANSAS THIS MORNING. THIS SYSTEM BROUGHT SOME MEASURABLE SNOW TO FAR
WESTERN PORTIONS OF SOUTHWEST KANSAS. BY EARLY AFTERNOON THE
SHORTWAVE HAD MOVED INTO EASTERN KANSAS WITH CLEARING SKIES IN ITS
WAKE. THERE WAS SOME LINGERING STRATUS ALONG WITH LIGHT SNOW
FLURRIES OUT ALONG THE COLORADO BORDER BEING FORCED BY SOME WEAK PVA
AND LOW LEVEL UPSLOPE. RUC13 MODEL CROSS SECTIONS SHOW THIS AREA OF
CLOUDS/PRECIPITATION DECREASING THROUGH THE NEXT FEW HOURS. VISIBLE
SATELLITE LOOPS SHOW THE AREA OF STRATUS ALREADY STARTING TO
DIMINISH. SKIES SHOULD BE MOSTLY CLEAR ACROSS ALL OF SOUTHWEST
KANSAS BY THIS EVENING.
WITH THE COLD HIGH PRESSURE AIRMASS IN PLACE ACROSS WESTERN KANSAS,
CLEAR SKIES AND LIGHT WINDS THIS EVENING WILL RESULT IN TEMPERATURES
FALLING TO BELOW FREEZING FAIRLY SOON AFTER SUNSET. OVERNIGHT LOWS
WILL BE FALLING INTO THE LOWER TO MIDDLE 20S ACROSS THE ENTIRE AREA
OVERNIGHT. WITH THIS IN MIND, WILL CONVERT THE HARD FREEZE WATCH TO
A HARD FREEZE WARNING FOR THE AREA ALONG AND SOUTH OF A LINE FROM
JOHNSON TO JETMORE AND LARNED. THE AREA FROM SYRACUSE THROUGH
DIGHTON SAW A GOOD FREEZE LAST NIGHT SO THEY ARE DONE FOR THE YEAR
AS ARE AREAS UP TOWARD I-70. ANOTHER WEAK AND FAST MOVING SHORTWAVE
TROUGH WILL BE APPROACHING THE CENTRAL HIGH PLAINS LATER TONIGHT.
THIS COULD SPREAD SOME HIGH CLOUDINESS INTO PARTS OF WESTERN KANSAS.
IN ADDITION, THE SURFACE HIGH PRESSURE WILL BE MOVING INTO EASTERN
KANSAS LATER TONIGHT WHILE PRESSURE FALLS WILL ENSUE ALONG THE
EASTERN SLOPES OF THE ROCKIES. THIS COULD RESULT IN TEMPERATURES
RISING SOMEWHAT LATE TONIGHT.
SOUTHERLY WINDS WILL BECOME GUSTY FROM THE SOUTH ON SATURDAY AS THE
SURFACE PRESSURE GRADIENT INCREASES. ONLY SOME SCATTERED HIGH
CLOUDINESS IS EXPECTED DURING THE DAY. BASED ON MODEL 850
TEMPERATURE FORECASTS, HIGHS ON SATURDAY SHOULD ONLY CLIMB INTO THE
LOWER 50S IN MOST AREAS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 305 AM CDT FRI OCT 26 2012
MODELS THIS MORNING WERE SIMILAR TO PREVIOUS RUNS IN MOVING AN
UPPER RIDGE ACROSS THE WESTERN UNITED STATES LATE THIS WEEKEND AS
AN UPPER LEVEL TROUGH APPROACHES THE EASTERN UNITED STATES. AT THE
SURFACE AN AREA OF HIGH PRESSURE THAT WILL BE LOCATED ACROSS THE
CENTRAL PLAINS ON SATURDAY WILL START TO SLOWLY SLIDE EAST AS
SURFACE PRESSURES BEGIN TO FALL ALONG THE WESTERN HIGH PLAINS.
925MB AND 850MB LEVEL TEMPERATURE TRENDS FROM 00Z SATURDAY TO 00Z
SUNDAY DO INDICATE THAT TEMPERATURES WILL WARM FEW DEGREES AND
BASED ON THIS WARMING WILL LEARN TOWARDS THE CONSMOS FOR HIGHS
SATURDAY AFTERNOON.
FROM SUNDAY THROUGH THE FIRST HALF OF THE WORK WEEK A WARMING
TREND CAN BE EXPECTED AS THE WESTERN UNITED STATES UPPER LEVEL
RIDGE MOVES EAST ACROSS THE ROCKIES AND A UPPER LEVEL NORTHEAST
PACIFIC TROUGH/LOW BEGINS TO APPROACH THE WEST COAST. AT THIS TIME
THE CURRENT WARMING TREND WITH HIGHS REBOUNDING BACK INTO THE LOW
TO MID 60S BY MONDAY AND THEN EVEN A FEW 70S BECOMING POSSIBLE BY
TUESDAY STILL LOOKS ON TRACK. DID BUMP TEMPERATURES UP A FEW
DEGREES ON SUNDAY AND MONDAY BASED ON THE LATEST 00Z 850MB
TEMPERATURES AT 00Z MONDAY AND 00Z TUESDAY.
WEDNESDAY AND THURSDAY MODELS BEGIN TO DIVERGE ON HOW THEY
HANDLE OUR NEXT EASTERN PACIFIC UPPER LEVEL SYSTEM AS IT CROSSES
THE WESTERN UNITED STATES. AT THIS TIME CONFIDENCE IS NOT HIGH ON
WHICH SOLUTION WILL BE MORE CORRECT SO HAVE DECIDED TO STAY CLOSE
TO THE LATEST CREXTENDFCST_INIT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1228 PM CDT FRI OCT 26 2012
MVFR CEILINGS ARE RAPIDLY ERODING ACROSS WEST CENTRAL AND SOUTHWEST
KANSAS LATE THIS MORNING. ALL THE TAF SITES SHOULD BE VFR AT THE
BEGINNING OF THIS TAF PERIOD. SOME LINGERING AREAS OF LOW CEILINGS
WEST OF GARDEN CITY AND SOUTH OF HAYS SHOULD BE DISSIPATING BY 21Z.
VFR CONDITIONS ALONG WITH LIGHT AND VARIABLE WINDS WILL PREVAIL THROUGH
12Z SATURDAY. ON SATURDAY, SURFACE HIGH PRESSURE WILL MOVE INTO EASTERN
KANSAS WHILE PRESSURES START TO LOWER IN THE LEE SLOPES OF THE ROCKIES.
SOUTHERLY WINDS WILL INCREASE INTO THE 10 TO 20 KNOT RANGE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 22 52 29 60 / 0 0 0 0
GCK 24 52 28 61 / 0 0 0 0
EHA 25 54 31 61 / 0 0 0 0
LBL 23 54 28 62 / 0 0 0 0
HYS 22 50 26 58 / 0 0 0 0
P28 23 52 29 62 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
HARD FREEZE WARNING FROM 10 PM THIS EVENING TO 9 AM CDT SATURDAY
FOR KSZ064>066-074>081-084>090.
&&
$$
SHORT TERM...GERARD
LONG TERM...BURGERT
AVIATION...GERARD
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1144 AM MDT FRI OCT 26 2012
.UPDATE...
ISSUED AT 1140 AM MDT FRI OCT 26 2012
ONLY A FEW CHANGES MADE TO GOING FORECAST OTHER THAN TO TAPER OFF
POPS OVER EASTERN COLORADO THRU THE MORNING BASED ON RADAR TRENDS.
THE MID-LEVEL TROUGH HAS LIFTED OUT OF THE AREA AND WEAKENED AND
WILL CONTINUE TO LOSE ITS INFLUENCE ON THE AREA THIS AFTERNOON.
WEAK FLOW AND HIGH MOISTURE CONTENT IN THE LOWER ATMOSPHERE WILL
TRANSLATE TO MOSTLY CLOUDY SKIES THIS AFTERNOON WITH ONLY SLOW
CLEARING. BY LATE AFTERNOON ENOUGH MOISTURE SHOULD MIX OUT TO
ERODE LOWER CLOUD DECK.
THE SFC HIGH NOW OVER THE AREA NOW WILL MOVE OFF TO THE EAST
TONIGHT TURNING WINDS TO A LIGHT SOUTHEAST DIRECTION OVERNIGHT.
MID CLOUDS WILL MOVE IN AFTER MIDNIGHT AS A WEAK TROUGH ALOFT
SKIRTS THE AREA TO THE NORTH.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 236 AM MDT FRI OCT 26 2012
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOW LARGE SCALE TROUGH ACROSS
THE NORTHERN PLAINS WITH A SHORTWAVE TROUGH OVER CENTRAL COLORADO.
RADAR COMPOSITE SHOWS LIGHT SNOW EXTENDING ACROSS EASTERN COLORADO
JUST ENTERING THE FAR WESTERN EXTENT OF OUR CWA. THIS HAS FORMED
ALONG AN AXIS OF H7 FRONTOGENESIS AHEAD OF H7 TROUGH AXIS. AS MEAN
H5/H7 TROUGH SHIFTS EAST LIGHT SNOW SHOULD CONTINUE TO SPREAD EAST
TOWARDS THE CO/KS STATE LINE. BEST FORCING/MID LEVEL MOISTURE SHOULD
REMAIN OVER THE WESTERN CWA. LATEST SHORT RANGE GUIDANCE GENERALLY
KEEPS LIGHT SNOW OVER OUR EASTERN COLORADO COUNTIES AND FAR WESTERN
KS THROUGH 15Z...WITH SUBSIDENCE AND ISENTROPIC DOWNGLIDE
OVERSPREADING THE CWA PUTTING AN END TO PRECIP CHANCES BY MIDDAY.
WE WILL CONTINUE TO SEE BELOW NORMAL TEMPERATURES TODAY AND TONIGHT
WITH THE SAME COLD AIR MASS STILL IN PLACE. HIGHS TODAY WILL BE
SIMILAR TO FRIDAY WITH AFTERNOON TEMPS IN THE UPPER 30S ACROSS THE
WEST AND MID 40S ACROSS THE EAST. CLOUD COVER COULD LIMIT
RADIATIONAL COOLING TONIGHT...HOWEVER WITH THE COLD AIR MASS STILL
IN PLACE LOWS SHOULD STILL DROP TO THE MID TO UPPER 20S FOR MOST
LOCATIONS...AND NEAR 20F WHERE CLOUDS CLEAR OUT.
NW FLOW DEVELOPS OVER THE CWA FRIDAY AS H5 RIDGE BUILDS OVER THE
WESTERN US AND BEGINS TO SHIFT TOWARDS THE CENTRAL ROCKIES THROUGH
THE WEEKEND. GFS HAS INDICATED A WEAK SHORTWAVE TROUGH WILL MOVE
JUST NORTH OF THE CWA IN NEBRASKA SATURDAY. MOST GUIDANCE
GENERALLY INDICATES STORM TRACK SHOULD REMAIN NORTH OF OUR
CWA...SO I KEPT DRY FORECAST IN PLACE. AIR MASS OVER THE CWA
SHOULD SLOWLY MODERATE WITH HIGHS IN THE LOW 50S SATURDAY...AND
UPPER 50S ON SUNDAY.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 236 AM MDT FRI OCT 26 2012
DRY CONDITIONS WILL CONTINUE THROUGH MOST OF NEXT WEEK AS THE UPPER
LEVEL RIDGE REMAINS OVER THE WESTERN HALF OF THE CONUS. MID WEEK AN
UPPER LEVEL TROUGH MOVES ONSHORE OVER THE PACIFIC NORTHWEST...MOVING
INTO THE CENTRAL PLAINS BY THE START OF THE WEEKEND. THE GEFS
MEMBERS DISAGREE WITH THE TRACK OF THE TROUGH...WITH MOST MEMBERS
KEEPING IT NORTH OF THE AREA. TEMPERATURES THROUGH THURSDAY WILL BE
NORMAL...WITH BELOW NORMAL TEMPERATURES IN STORE AS A COLD FRONT
MOVES THROUGH FRIDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1125 AM MDT FRI OCT 26 2012
MVFR CEILINGS AROUND FL020-025 AT BOTH TERMINALS THIS AFTERNOON...
DISSIPATING BY 00Z. VFR CONDITIONS WITH INCREASING CLOUDS AT FL200
AFTER 06Z FOR REMAINDER OF TAF PERIOD. SURFACE WINDS WILL BE LIGHT
AND VARIABLE FOR THE AFTERNOON WITH A SFC HIGH CENTERED OVER THE
REGION. WINDS WILL GRADUALLY BECOME SOUTHEAST AT 5-10 KTS TONIGHT
AS THE HIGH MOVES OFF TO THE EAST.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...DLF
SHORT TERM...DR
LONG TERM...JTL
AVIATION...DLF
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
644 PM EDT FRI OCT 26 2012
.Forecast Update...
Updated at 640 PM EDT Fri Oct 26 2012
Updated the forecast to adjust POPs and temps. Latest radar imagery
depicts the most widespread rains over northern KY and southeast
Indiana. This area of rain will continue to slowly move NE out of
our region this evening. However, another area of steady showers is
blossoming over northwest TN which is predicted (by RR and HRRR high
res models) to move northeast over central and east central KY
through around midnight. Thus, have tried to better time these
areas of steady rains throughout the evening hours in the forecast
grids.
Also did a slight tweak to hourly temps for this evening. They
should hold steady in areas already in mid 40s or fall into the 40s
in areas over east central KY that were around 50 or the lower 50s
as of 2230Z. New forecast products out shortly.
&&
.Short Term (Tonight through Saturday Night)...
Issued at 325 PM EDT Fri Oct 26 2012
The strong cold front has pushed through central Kentucky, with the
leading edge of post-frontal precip extending from near Frankfort to
Glasgow to just east of Nashville, TN as of 19Z. Temps will quickly
drop into the upper 40s as the rain spreads into the Bluegrass and
Lake Cumberland, and the ZFP may need a pre-1st period to account
for this.
Otherwise expect high POPs to continue into the evening hours as
this rain shield takes its sweet time moving east. Precip really
thins out over western Kentucky and western Tennessee, which points
to rain shutting off from SW to NE across the area during the night.
Will cut back POPs but with broad SW flow over the top of a shallow
cold air mass, not confident enough to dry things out completely
overnight. Temps will continue to drop in cold air advection, but
plenty of wind and cloud cover will keep lows from really bottoming
out. Look for upper 30s over parts of southern Indiana, but mainly
lower to mid 40s elsewhere.
Still hanging on to some morning precip in the Bluegrass on
Saturday, but this could be too generous. While there will be some
clearing it is still a chilly Canadian air mass. Low-confidence temp
forecast as it will depend heavily on how much clearing occurs.
Split the difference between MOS guidance with highs in the mid-50s,
except some lower 50s in the Bluegrass. Saturday night will be a few
degrees cooler, with most locations dipping into the 30s. Will not
be quite ideal for radiational cooling given a modest amount of
cloud cover and north winds staying up around 6 or 7 kts. Therefore
will not include any frost and the spread in temps will be rather
small.
.Long Term (Sunday through Friday)
Issued at 250 PM EDT Fri Oct 26 2012
What a change from just 24 hours ago! The long term forecast will
feature temperatures at least 10-15 degrees below normal each day.
Winds early on will be from the north and gusty, with how gusty
depending on how close Sandy gets to our forecast area. Winds will
shift slowly through the period to more westerly by midweek, where
it looks to remain the rest of the week. Tuesday looks to be the
most breezy, again based on hurricane center`s forecast proximity of
Sandy to our region. The remnants of Sandy look to continue to
influence our flow through the end of the work week.
The eastern forecast area will have the best chance for light precip
Sunday through Wednesday. Temperatures may be cool enough for a mix
Monday night and Tuesday night as well. Have thrown in a slight
chance for rain or snow for those periods. Do not expect
accumulations, as the ground still will be too warm for that.
Only other concern for the forecast would be any freezing Sunday
night through Wednesday night. Right now do not have any solid
freeze on any of the nights, just right around the freezing mark.
The wind should stay up enough each night to keep temperatures
fairly uniform and also to reduce the threat for frost.
&&
.Aviation (18Z TAF Issuance)...
Issued at 105 PM EDT Fri Oct 26 2012
Surface cold front has pushed through central Kentucky, with a
respectable post-frontal rain shield that has brought IFR conditions
into SDF and almost to the doorstep of BWG. Ahead of this rain area,
ceilings are already into fuel-alternate MVFR.
Expect the rain to make its way into BWG by the valid time of the
TAF, and into LEX by about 19Z, with similar restrictions to what we
have already seen at SDF. METARs over western Kentucky and even as
close as FTK have shown enough fluctuation that we will carry MVFR,
with a TEMPO for IFR conditions for most of the afternoon.
Rain and low clouds will persist into the night but will be a close
call on IFR/MVFR conditions. Will keep it just barely MVFR to
reflect that uncertainty. Precip should taper off and ceilings
should improve from south to north, but will be mid to late morning
before the fuel-alternate threshold is exceeded. Otherwise will
maintain status quo with modest north winds.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........AMS
Short Term.......RAS
Long Term........RJS
Aviation.........RAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
115 PM EDT FRI OCT 26 2012
.UPDATE...
ISSUED AT 1216 PM EDT FRI OCT 26 2012
HAVE UPDATED THE NDFD AND ZFP. MAIN CHANGE WAS TO MAKE ADJUSTMENTS TO
TIMING OF OVERCAST CLOUD DECK WHICH WILL MOVE INTO THE WESTERN PART
OF THE FORECAST AREA. LOW CLOUDS BEHIND THE COLD FRONT WILL
OVERSPREAD THE FAR WESTERN PART OF THE AREA THIS AFTERNOON.
TEMPERATURES IN THIS AREA WILL BEGIN TO FALL AS COLD AIR ADVECTION
KICKS IN AND SOLAR HEATING DIMINISHES. COULD SEE SOME SCATTERED
SHOWERS OUT AHEAD OF THE COLD FRONT...SO WILL CARRY 20 TO 30 PERCENT
PROBABILITY OF SHOWERS EVEN IN THE EAST FOR THIS AFTERNOON. POST FRONTAL
RAINS CURRENTLY IN CENTRAL AND WEST KY WILL MOVE INTO THE JACKSON
FORECAST AREA TONIGHT...BUT EXPECT THE COVERAGE AND INTENSITY OF THIS
RAIN TO DECREASE WITH TIME.
UPDATE ISSUED AT 937 AM EDT FRI OCT 26 2012
BASED ON CURRENT RADAR TRENDS AND HRRR FORECAST IT APPEARS SHOWERS
SHOULD HOLD OFF UNTIL LATE AFTERNOON OR EVENING. THIS IS WELL HANDLED
IN CURRENT NDFD. MADE ONLY MINOR GRID CHANGES BASED ON CURRENT
OBSERVATIONS WITH NO CHANGES TO PRECIPITATION TIMING.
UPDATE ISSUED AT 805 AM EDT FRI OCT 26 2012
ONLY MINOR GRID CHANGES WERE NEEDED BASED ON LATEST OBSERVATIONS...
WITH NO SIGNIFICANT IMPACT ON THE FORECAST
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 400 AM EDT FRI OCT 26 2012
THERE IS GOOD MODEL AGREEMENT DURING THE PERIOD. A COLD FRONT
STRETCHED FROM WESTERN OH THROUGH WESTERN KY DURING THE PREDAWN
HOURS...AND IT WILL MOVE SE THROUGH OUR FORECAST AREA TODAY.
CONVECTION AHEAD OF THE FRONT SHOULD REMAIN CAPPED AROUND 10K FEET
TODAY...WITH CLOUD TOP TEMPS REMAINING TO WARM FOR ICE
FORMATION...AND HENCE LIMITING PRECIP POTENTIAL. HOWEVER...CLOUD
DEPTH SHOULD BE ENOUGH FOR SOME LIGHT SHOWERS...AND WILL USE 20-30
PERCENT POPS. THE BEST SHOT AT PRECIP WILL COME TONIGHT INTO SATURDAY
AS WARM AIR ADVECTION BRINGS ISENTROPIC LIFT ABOVE THE FRONTAL
INVERSION AND IS AIDED BY LIFT IN THE RIGHT ENTRANCE REGION OF AN
UPPER JET. DEEP MOISTURE WILL BE LOST LATER ON SATURDAY AND SATURDAY
NIGHT...WITH PRECIP BECOMING LIGHTER AND MORE SPARSE. IN
ADDITION...MUCH COOLER AIR MOVING IN BEHIND THE FRONT WILL PUT AN END
TO OUR MILD WEATHER.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 330 AM EDT FRI OCT 26 2012
THE LONG TERM PERIOD WILL BE DOMINATED BY DEEP TROUGHING OVER THE
EASTERN U.S. AS STRONG BLOCKING OVER THE NORTHERN ATLANTIC KEEPS
EVERYTHING LOCKED IN PLACE. THE BIG QUESTION CONTINUES TO REVOLVE
AROUND HOW HURRICANE SANDY BEHAVES EARLY NEXT WEEK. AFTER SOME
RELATIVE AGREEMENT SHOWED UP IN THE 25/12Z PROGS REGARDING SANDY/S
LANDFALL AND SUBSEQUENT PATH...THE 26/00Z RUNS HAVE SPREAD BACK OUT
AGAIN. LANDFALL NOW RANGES FROM MAINE IN THE GEM...THE NEW YORK CITY
VICINITY IN THE GFS AND UKMET...TO THE DELMARVA IN THE ECMWF. THE
ECMWF CONTINUES TO OFFER THE MOST IMPACT FOR EAST KENTUCKY WITH
SEVERAL INCHES OF WET SNOW AND GUSTY WINDS IN THE CARDS SHOULD THAT
SOLUTION PAN OUT. HOWEVER...WITH SO MUCH TIME REMAINING BEFORE
LANDFALL...STILL AT LEAST 4 DAYS...AND SO MANY VARIABLES TO
CONSIDER...WE WILL CONTINUE TO SIDE WITH A STRICT MODEL BLEND
APPROACH FOR FORECAST DETAILS AND STAY AWAY FROM SIDING WITH ANY ONE
MODEL.
A COLD FRONT WILL BE STATIONARY JUST TO OUR EAST ON SUNDAY.
CONSIDERABLE CLOUD COVER AND A FEW SHOWERS WILL LINGER BEHIND THIS
FRONT INTO SUNDAY NIGHT. WE WILL THEN CONTINUE TO MENTION A LOW
CHANCE OF PRECIPITATION FROM MONDAY THROUGH WEDNESDAY NIGHT FOR MOST
AREAS FACTORING IN THE POSSIBILITY OF SOME IMPACT FROM SANDY. TEMPS
WILL SUPPORT A MENTION OF SNOW AS WELL...ESPECIALLY DURING THE
OVERNIGHT AND EARLY MORNING HOURS.
TEMPERATURES WILL REMAIN IN THE 40S FOR MOST LOCATIONS EACH DAY
THROUGH THE PERIOD. OVERNIGHT LOWS ARE EXPECTED TO FALL INTO THE
30S...AND SHOULD SANDY TAKE A MORE NORTHERN ROUTE INLAND AND HAVE
LESS IMPACT ON OUR WEATHER...THEN 20S WILL BE POSSIBLE NEXT WEEK.
RIGHT NOW...OUR FORECAST CONTAINS A LITTLE TOO MUCH CLOUD COVER AND
WIND EACH NIGHT TO FORECAST TEMPS MUCH BELOW 32 DEGREES FOR ANY ONE
PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 114 PM EDT FRI OCT 26 2012
A COLD FRONT WILL MOVE ACROSS THE AREA THIS AFTERNOON AND EVENING. A
FEW ISOLATED LIGHT SHOWERS MAY OCCUR AHEAD OF THE FRONT...BUT MOST
OF THE POOR WEATHER CONDITIONS WILL BE BEHIND THE FRONT. AN EXTENSIVE
AREA OF LOW CLOUD WILL SPREAD ACROSS THE FORECAST AREA FROM THE
NORTHWEST TONIGHT WITH CEILINGS DROPPING TO IFR. IFR CONDITIONS
SHOULD PREVAIL WELL INTO THE DAY ON SATURDAY...WITH CEILINGS
THEN LIFTING TO MVFR. AN EXTENSIVE AREA OF RAIN CURRENTLY OVER
CENTRAL AND WESTERN KY WILL DECREASE IN COVERAGE AND INTENSITY AS IT
MOVES EAST...BUT EASTERN KY WILL STILL SEE SOME PERIODS OF LIGHT RAIN
TONIGHT. WINDS WILL SHIFT TO THE NORTH WITH THE FRONTAL PASSAGE AND NORTH
WINDS WILL CONTINUE ON SATURDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...HAL
LONG TERM....ABE
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
109 PM EDT FRI OCT 26 2012
...Updated Aviation Discussion...
.Forecast Update...
Updated at 1005 AM EDT Fri Oct 26 2012
Front has pushed well into the Bluegrass already this morning. Rain
lagging well behind as it has yet to cross I-65. Did a quick update
to the forecast to better break down precip timing, as well as to
clip a few degrees off max temps in the Bluegrass. Still a bit
concerned that those high temps in the Bluegrass will need to be
trimmed back even further, but there is still a window for a little
bit of warming before precip arrives.
&&
.Short Term (Today through Saturday)...
Issued at 326 AM EDT Fri Oct 26 2012
...Sharp cold front moving through the region today will result in
falling temperatures...
Well advertised potent upper level trough and associated surface
cold front are heading through the region early this morning. The
models have been playing catch up with respect to the timing and the
latest HRRR and RAP guidance seems to have a good handle on things.
Based on WSR-88D velocity moments, the front is just west of a
KSDF-KFTK-KBWG line. The front should cross the I-65 corridor
within the next hour and then head toward the I-75 corridor towards
sunrise. A brief period of breezy, perhaps gusty winds will
accompany the front as it pushes through with winds shifting from
the south to the northwest. Precipitation is lagging behind the
front by a few hours, so in the near term, dry conditions are
expected. Based on upstream observations, we`re seeing a 12-15
degree drop behind the front, so while temperatures in the central
sections are still in the mid-upper 60s, those reading will fall
quickly over the next couple of hours.
For today, the frontal boundary is forecast to push eastward through
the day. Some pre-frontal warming may occur in the east just ahead
of the front, but temperatures by and large will fall throughout the
day. All of the deterministic and ensemble guidance continues to
show that post-frontal precipitation is very likely, so we have
bumped up the clouds and precipitation chances a bit for today.
Highest PoPs today will be in the west and central sections with
higher PoPs in the east holding off until later this afternoon and
evening. As for temperatures, highs today will range from the upper
40s to the lower 50s in the west and central sections. Upper 50s to
the lower 60s are likely in the east, but these will occur early as
temperatures fall into the upper 40s to lower 50s by evening.
For tonight, the aforementioned frontal boundary will continue to
surge eastward. Lagging post-frontal precipitation band will likely
continue to slowly move eastward through the forecast area. It
appears that a weak upper level wave will pass overhead tonight,
which may enhance our PoP chances for the evening and early
overnight hours. Will keep chance PoPs in for the far
west/northwest sections with likely PoPs in the central and eastern
sections. Overall, best chances of rain tonight look to be over our
eastern forecast area. Precipitation should generally be exiting
the forecast area by dawn and drier air will attempt to punch into
our west/northwest sections late. With this drier air coming in,
we`re likely to see some partial clearing toward sunrise which will
allow for a gradient of temperatures across the area. Overnight
lows should range from the upper 30s in the far west/northwest with
lower 40s in the central and lower-mid 40s in the east.
For Saturday, high pressure to the west will continue to slowly
build into the region. This will result in clearing working across
the forecast area from west to east. Typically the models are too
fast at clearing things out. In addition, cold air advection aloft
will likely result in a stratocumulus deck building in. Partly
cloudy conditions look reasonable for areas west of I-65 with mostly
cloudy conditions east of I-65...though skies will likely become
mostly clear by evening. As for temperatures, highs will be in the
upper 40s to around 50 in the east/northeast with lower-middle 50s
across the central and western sections.
.Long Term (Saturday Night through Thursday)
Issued at 305 AM EDT Fri Oct 26 2012
Across the country, the big weather story early next week will
concern the mid-Atlantic and our northeastern states. Hurricane
Sandy, now a category one hurricane east of Florida is increasingly
likely to begin developing into into an intense extra-tropical
cyclone by Sunday well east of North Carolina. The majority of the
most recent guidance shows a deep 500mb trough forming over the
Appalachians. Should this occur, this cyclone would be pulled
northwest towards New York or southern New England by late Monday
with an exceptionally deep surface low and gale force winds.
The unusual track of this storm is a result of strong blocking
across the entire Atlantic basin. Upstream from this, across the
Lower Ohio Valley and midwest, northerly flow already in place
Sunday will simply not budge, continuing through at least Thursday.
A lengthy period of cool weather is practically certain for the
Commonwealth and southern Indiana. Clearing is forecast to have
taken place across southern Illinois and western Kentucky by late
Saturday. However, cloud cover is likely to linger across eastern
Kentucky into Sunday morning. Across central Kentucky, cloud cover
will remain a tricky forecast through Sunday as the NAM and the GFS
have contrasting forecasts on how quickly clouds erode over eastern
Kentucky.
At the surface, a ridge of high pressure extending southward along
the Mississippi River on Sunday simply will not budge. Northerly
surface winds are likely for our region for all of the early portion
of next week as the afore-mentioned deep nor`easter creeps slowly
over southern New England.
Temperatures will remain pretty consistent Sunday through Wednesday
in this basically blocky weather pattern. Expect highs in the lower
to mid 50 each day, with Monday potentially a bit cooler. Lows will
bottom out in the lower to mid-30s.
Expect clear to partly cloudy skies Monday through Thursday. It is
possible that overcast skies associated with the western edge of the
New England storm may push as far west as central Kentucky late
Monday or Tuesday if some of more western model solutions verify.
&&
.Aviation (18Z TAF Issuance)...
Issued at 105 PM EDT Fri Oct 26 2012
Surface cold front has pushed through central Kentucky, with a
respectable post-frontal rain shield that has brought IFR conditions
into SDF and almost to the doorstep of BWG. Ahead of this rain area,
ceilings are already into fuel-alternate MVFR.
Expect the rain to make its way into BWG by the valid time of the
TAF, and into LEX by about 19Z, with similar restrictions to what we
have already seen at SDF. METARs over western Kentucky and even as
close as FTK have shown enough fluctuation that we will carry MVFR,
with a TEMPO for IFR conditions for most of the afternoon.
Rain and low clouds will persist into the night but will be a close
call on IFR/MVFR conditions. Will keep it just barely MVFR to
reflect that uncertainty. Precip should taper off and ceilings
should improve from south to north, but will be mid to late morning
before the fuel-alternate threshold is exceeded. Otherwise will
maintain status quo with modest north winds.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........RAS
Short Term.......MJ
Long Term........JSD
Aviation.........RAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
1216 PM EDT FRI OCT 26 2012
.UPDATE...
ISSUED AT 1216 PM EDT FRI OCT 26 2012
HAVE UPDATED THE NDFD AND ZFP. MAIN CHANGE WAS TO MAKE ADJUSTMENTS TO
TIMING OF OVERCAST CLOUD DECK WHICH WILL MOVE INTO THE WESTERN PART
OF THE FORECAST AREA. LOW CLOUDS BEHIND THE COLD FRONT WILL
OVERSPREAD THE FAR WESTERN PART OF THE AREA THIS AFTERNOON.
TEMPERATURES IN THIS AREA WILL BEGIN TO FALL AS COLD AIR ADVECTION
KICKS IN AND SOLAR HEATING DIMINISHES. COULD SEE SOME SCATTERED
SHOWERS OUT AHEAD OF THE COLD FRONT...SO WILL CARRY 20 TO 30 PERCENT
PROBABILITY OF SHOWERS EVEN IN THE EAST FOR THIS AFTERNOON. POST FRONTAL
RAINS CURRENTLY IN CENTRAL AND WEST KY WILL MOVE INTO THE JACKSON
FORECAST AREA TONIGHT...BUT EXPECT THE COVERAGE AND INTENSITY OF THIS
RAIN TO DECREASE WITH TIME.
UPDATE ISSUED AT 937 AM EDT FRI OCT 26 2012
BASED ON CURRENT RADAR TRENDS AND HRRR FORECAST IT APPEARS SHOWERS
SHOULD HOLD OFF UNTIL LATE AFTERNOON OR EVENING. THIS IS WELL HANDLED
IN CURRENT NDFD. MADE ONLY MINOR GRID CHANGES BASED ON CURRENT
OBSERVATIONS WITH NO CHANGES TO PRECIPITATION TIMING.
UPDATE ISSUED AT 805 AM EDT FRI OCT 26 2012
ONLY MINOR GRID CHANGES WERE NEEDED BASED ON LATEST OBSERVATIONS...
WITH NO SIGNIFICANT IMPACT ON THE FORECAST
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 400 AM EDT FRI OCT 26 2012
THERE IS GOOD MODEL AGREEMENT DURING THE PERIOD. A COLD FRONT
STRETCHED FROM WESTERN OH THROUGH WESTERN KY DURING THE PREDAWN
HOURS...AND IT WILL MOVE SE THROUGH OUR FORECAST AREA TODAY.
CONVECTION AHEAD OF THE FRONT SHOULD REMAIN CAPPED AROUND 10K FEET
TODAY...WITH CLOUD TOP TEMPS REMAINING TO WARM FOR ICE
FORMATION...AND HENCE LIMITING PRECIP POTENTIAL. HOWEVER...CLOUD
DEPTH SHOULD BE ENOUGH FOR SOME LIGHT SHOWERS...AND WILL USE 20-30
PERCENT POPS. THE BEST SHOT AT PRECIP WILL COME TONIGHT INTO SATURDAY
AS WARM AIR ADVECTION BRINGS ISENTROPIC LIFT ABOVE THE FRONTAL
INVERSION AND IS AIDED BY LIFT IN THE RIGHT ENTRANCE REGION OF AN
UPPER JET. DEEP MOISTURE WILL BE LOST LATER ON SATURDAY AND SATURDAY
NIGHT...WITH PRECIP BECOMING LIGHTER AND MORE SPARSE. IN
ADDITION...MUCH COOLER AIR MOVING IN BEHIND THE FRONT WILL PUT AN END
TO OUR MILD WEATHER.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 330 AM EDT FRI OCT 26 2012
THE LONG TERM PERIOD WILL BE DOMINATED BY DEEP TROUGHING OVER THE
EASTERN U.S. AS STRONG BLOCKING OVER THE NORTHERN ATLANTIC KEEPS
EVERYTHING LOCKED IN PLACE. THE BIG QUESTION CONTINUES TO REVOLVE
AROUND HOW HURRICANE SANDY BEHAVES EARLY NEXT WEEK. AFTER SOME
RELATIVE AGREEMENT SHOWED UP IN THE 25/12Z PROGS REGARDING SANDY/S
LANDFALL AND SUBSEQUENT PATH...THE 26/00Z RUNS HAVE SPREAD BACK OUT
AGAIN. LANDFALL NOW RANGES FROM MAINE IN THE GEM...THE NEW YORK CITY
VICINITY IN THE GFS AND UKMET...TO THE DELMARVA IN THE ECMWF. THE
ECMWF CONTINUES TO OFFER THE MOST IMPACT FOR EAST KENTUCKY WITH
SEVERAL INCHES OF WET SNOW AND GUSTY WINDS IN THE CARDS SHOULD THAT
SOLUTION PAN OUT. HOWEVER...WITH SO MUCH TIME REMAINING BEFORE
LANDFALL...STILL AT LEAST 4 DAYS...AND SO MANY VARIABLES TO
CONSIDER...WE WILL CONTINUE TO SIDE WITH A STRICT MODEL BLEND
APPROACH FOR FORECAST DETAILS AND STAY AWAY FROM SIDING WITH ANY ONE
MODEL.
A COLD FRONT WILL BE STATIONARY JUST TO OUR EAST ON SUNDAY.
CONSIDERABLE CLOUD COVER AND A FEW SHOWERS WILL LINGER BEHIND THIS
FRONT INTO SUNDAY NIGHT. WE WILL THEN CONTINUE TO MENTION A LOW
CHANCE OF PRECIPITATION FROM MONDAY THROUGH WEDNESDAY NIGHT FOR MOST
AREAS FACTORING IN THE POSSIBILITY OF SOME IMPACT FROM SANDY. TEMPS
WILL SUPPORT A MENTION OF SNOW AS WELL...ESPECIALLY DURING THE
OVERNIGHT AND EARLY MORNING HOURS.
TEMPERATURES WILL REMAIN IN THE 40S FOR MOST LOCATIONS EACH DAY
THROUGH THE PERIOD. OVERNIGHT LOWS ARE EXPECTED TO FALL INTO THE
30S...AND SHOULD SANDY TAKE A MORE NORTHERN ROUTE INLAND AND HAVE
LESS IMPACT ON OUR WEATHER...THEN 20S WILL BE POSSIBLE NEXT WEEK.
RIGHT NOW...OUR FORECAST CONTAINS A LITTLE TOO MUCH CLOUD COVER AND
WIND EACH NIGHT TO FORECAST TEMPS MUCH BELOW 32 DEGREES FOR ANY ONE
PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 756 AM EDT FRI OCT 26 2012
A COLD FRONT WILL MOVE THROUGH FROM NW TO SE DURING THE DAY TODAY...
BUT VFR IS EXPECTED TO PERSIST INTO TONIGHT. WELL BEHIND THE FRONT A
LOW OVERCAST WILL MOVE IN...RESULTING IN WIDESPREAD MVFR CONDITIONS
DEVELOPING FROM NW TO SE ACROSS THE FORECAST AREA BETWEEN 23Z AND
06Z...WITH LOCALIZED IFR. SHOWERS ARE ALSO FORECAST TO ARRIVE IN
WESTERN LOCATIONS FROM SOMERSET TO MOREHEAD NEAR AROUND 06Z...AND
THEN SLOWLY SPREAD SOUTHEAST OVERNIGHT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...HAL
LONG TERM....ABE
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
359 PM EDT FRI OCT 26 2012
.SYNOPSIS...
A SLOWLY MOVING EASTBOUND COLD FRONT WILL HERALD WETTER AND COLDER
CONDITIONS FOR THE UPPER OHIO VALLEY THIS WEEKEND. INTERACTION
BETWEEN THIS STRONG COLD FRONT AND NORTHBOUND HURRICANE SANDY MAY
LEAD TO A PERIOD OF HEAVY RAIN AND WINDY CONDITIONS MONDAY INTO
WEDNESDAY...WITH PERHAPS EVEN SOME SNOWFALL AS WELL.
&&
.NEAR TERM /THROUGH TONIGHT/...
BASED ON RECENT WRF-NMM AND RAP MODEL OUTPUT...MADE SMALL ADJUSTMENTS
TO EARLIER FORECASTS...WHICH WERE MAINLY TO DELAY COLD FRONTAL
PASSAGE BY 1 OR 2 HOURS...AND TO DELAY ONSET OF POSTFRONTAL BAND
/ANAFRONT/ OF RAIN SHOWERS BY AS MUCH AS 4 HOURS...WITH MOST
PLACES EAST OF THE OHIO LINE NOT GETTING RAINFALL UNTIL LATE
TONIGHT.
STILL LOOKS AS THOUGH THE COLD FRONT WILL NOT REACH THE
APPALACHIAN WESTERN SLOPES UNTIL DAYTIME SATURDAY.
THIS CONTINUE TO
SHOW THE STRONG COLD FRONT AS THE MAIN WEATHER MAKER. DUE TO
RECENT MODEL OUTPUT...HAVE SLOWED PASSAGE OF THE STRONG COLD
FRONT INTO THE I-79 CORRIDOR BY AN HOUR OR SO LATE THIS AFTERNOON
INTO EARLY EVENING...WITH COLD FRONT NOT REACHING THE APPALACHIAN
MOUNTAINS BEFORE SATURDAY MORNING. STILL APPEARS THE BULK OF
SHOWERS WILL BE AFTER THE COLD FRONTAL PASSAGE.,,A S0-CALLED
ANA FRONT SCENARIO. CONTINUED CATEGORICAL RAIN CHANCES LATE TONIGHT
DUE TO EXPECTED
FORECASTED LOWS TO STILL BE 5 TO 10 DEGREES WARMER THAN NORMAL
BASED ON BLEND OF GFS LAMP...GFS MOS...NAM MOS...AND SREF MEAN
VALUES.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
CONCUR WITH RECENT SREF MODEL OUTPUT...WITH DETAILS FROM RECENT
WRF-NMM AND NAM MODEL OUTPUT...THAT THIS WILL BE A RAINY PERIOD
FOR MUCH OF THE UPPER OHIO VALLEY...DUE TO ENHANCED
FRONTOGENETICAL FORCING ASSOCIATED WITH INTERACTION BETWEEN THE
COLD FRONT AND A DEVELOPING JET STREAK ALOFT.
THE COLD FRONT ITSELF SHOULD REACH THE APPALACHIAN MOUNTAINS
DAYTIME SATURDAY...WITH THE ASSOCIATED POSTFRONTAL RAIN SHOWERS
LIKELY TO FINALLY REACH THE MOUNTAINS BY MIDDAY.
POSTFRONTAL COLD NORTHERLY WINDS PLUS CLOUDY SHOWERY CONDITIONS WILL
RESTRICT MUCH OF A TEMPERATURE WARM UP DAYTIME SATURDAY...WITH
ONLY THE MOUNTAINS HAVING WARMER THAN NORMAL HIGHS.
BASED ON BLEND OF GFS AND NAM MOS...FORECASTED LOWS SATURDAY NIGHT TO
BE NEAR OR SLIGHTLY WARMER THAN NORMAL DUE TO THICK CLOUDS AND
FREQUENT RAINFALL. HIGHS SUNDAY CAN BE 5 TO 8 DEGREES COLDER THAN
NORMAL.
THE NORTH WINDS GUSTING TO 20 TO 25 MPH WILL ADD TO THE WEEKEND
CHILL OR SO-CALLED RAW CONDITIONS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
MODEL AND ENSEMBLE SPREAD CONTINUES TO BE PROBLEMATIC FOR
FORECASTING THE WEATHER FOR THIS PERIOD.
TRENDS FROM THE GUIDANCE REALLY DO NOT SEEM TO BE FLOWING IN ONE
DIRECTION TODAY. THE 00Z ECMWF TRENDED HARD TO THE LEFT WITH
SANDY. THE GFS/GEFS MEMBERS GENERALLY MAINTAINED TRACK INTEGRITY
INTO BASICALLY NEW JERSEY. THE 12Z CANADIAN GLOBAL TRENDED WEST
AFTER THE 00Z FAILED TO EVEN PHASE SANDY AND THE EASTWARD MOVING
UPPER LEVEL SYSTEM FROM THE CENTER OF THE COUNTRY. THE SREF MEAN
FAVORED A SOLUTION NORTH OF THE ECMWF AND NEAR THE GEFS CONSENSUS.
A VERITABLE CORNUCOPIA OF SOLUTIONS FELL OUT OF ALL OF THE GLOBAL
GUIDANCE SUCH THAT A DETERMINISTIC FORECAST FEELS LIKE A BIT OF A
RISK MANAGEMENT EXERCISE...BUT TRY WE SHALL REGARDLESS.
YESTERDAY`S MODELS AND ENSEMBLE SOLUTIONS FELL IN A SIMILAR
ENVELOPE...HOWEVER AT THAT TIME...THE CANADIAN GLOBAL WAS AN
EASTERLY OUTLYING SOLUTION. TODAY THE CANADIAN TRENDED BACK TOWARD
THE SREF/GEFS TRACK CONSENSUS. HOWEVER...USING THE SREF IS
PROBLEMATIC IN THAT BY THE END OF THE SREF RUN...THE SREF MEAN
MSLP PLOTS ACTUALLY SHOW TWO CENTERS FOR SANDY...WHICH IS CLEARLY
INDICATIVE OF A BIMODAL SOLUTION DISTRIBUTION THAT YIELDS LESS
CONFIDENCE IN THE MEAN THAN WE WOULD OTHERWISE NORMALLY HAVE.
AS SUCH...WHILE CONFIDENCE IN THE SREF IS FAR FROM STELLAR...ITS
PROXIMITY TO THE CONSENSUS OF THE GEFS AND CANADIAN AS WELL AS THE
RECENT INSISTENCE OF THE GEFS ON LANDFALL INTO NEW JERSEY LEND
CREDENCE TO THESE SOLUTIONS. AS SUCH...THE FORECAST WILL CONTINUE
TO FAVOR A TRACK OF THE LOW LEVEL CIRCULATION FROM
SOUTHERN/CENTRAL NEW JERSEY TOWARD NORTH CENTRAL
PENNSYLVANIA...WITH ONLY A SLIGHT SOUTHWARD DEVIATION FROM THAT
FAVORED YESTERDAY.
THE NET RESULT IN THE FORECAST IS SOME NOMINAL WARMING OF THE
FORECAST AND ATTENDANT P-TYPE CHANGES GENERALLY FROM PITTSBURGH
NORTHWARD...WHILE COLDER AIR STILL LOOKS TO RULE THE ROOST ACROSS
THE SOUTHERN TIER OF THE FORECAST AREA. THERMAL PROFILES FROM
GUIDANCE CONTINUE TO SUGGEST NEARLY ISOTHERMAL PROFILES BELOW
ABOUT 5 KFT...SO EVEN WHERE THE ATMOSPHERE IS COLD ENOUGH TO
SUPPORT SNOW...A DEEP LAYER NEAR FREEZING AND GROUND TEMPERATURES
WELL ABOVE FREEZING WILL MAKE ACCUMULATION VERY DIFFICULT.
ADDITIONALLY...OMEGA PROFILES SUGGEST THE STRONGEST OMEGA AROUND
THE TROWAL REGION IS CENTERED FAR TOO LOW IN THE COLUMN...NEAR THE
-6 TO -8C RANGE...TO SUPPORT EFFICIENT ICE CRYSTAL GROWTH. AS
SUCH...EXCEPT WHERE OMEGA CAN BE EXTENDED UPWARD HIGHER INTO THE
COLUMN...SUCH AS OVER THE RIDGES WHERE OROGRAPHIC FORCING WILL
LIFT THE OMEGA PROFILE CLOSER TO THE -12C ISOTHERM...NOT ONLY WILL
SNOW ACCUMULATION BE PROBLEMATIC...BUT SNOW CRYSTAL GENERATION
WILL BE PROBLEMATIC. AS SUCH...IN THE COLDER SOUTHERN TIER OF THE
AREA...WHILE MIXING WITH SNOW SEEMS POSSIBLE...ACCUMULATING SNOWS
OUTSIDE OF THE RIDGES DO NOT.
AS FOR THE NOT-SO-COLD PART OF THE AREA AS THE EVENT UNFOLDS FROM
PITTSBURGH NORTHWARD...ENOUGH GUIDANCE HAS PUSHED AN ELEVATED WARM
LAYER OVER THIS AREA THAT THERE SHOULD LIKELY BE A WINDOW WHERE
THE WARM CONVEYOR BELT STRUCTURE BENDS BACK TOWARD THE NORTHERN
PART OF OUR CWA. WHILE IT WILL NOT BE WARM...ENHANCED MIXING
RATIOS AND LOW/MID-LEVEL FRONTOGENESIS OVERLAID WITH THE RIGHT
ENTRANCE OF AN ANTI-CYCLONICALLY CURVED SOUTH TO NORTH ORIENTED UPPER
JET RUNNING PARALLEL TO THE SURFACE FRONT MEAN THAT THIS IS
ESSENTIALLY A HEAVY PRECIPITATION EVENT THAT WOULD NORMAL OCCUR
IN THE MID-MISSISSIPPI VALLEY TURNED 90 DEGREES TO THE LEFT.
STRONG MOISTURE FLUX OFF THE ATLANTIC INTO A QUASI-STATIONARY
BOUNDARY WITH A BACKBUILDING JET AND STATIONARY UPPER DIVERGENCE
SIGNATURE SUGGEST THAT WITH SANDY`S PREFERRED TRACK TOWARD CENTRAL
PENNSYLVANIA...COPIOUS PRECIPITATION WILL BE LIKELY...PARTICULARLY
ACROSS THE NORTHERN HALF OF THE CWA...AND WITH A TRACK LIKE THE
ONE SUGGESTED ABOVE...THIS WOULD LIKELY BE A FAIRLY EFFICIENT RAIN
PRODUCER. AS SUCH...OCCASIONAL HEAVY RAIN WAS ADDED TO THE GRIDS
EARLY NEXT WEEK.
THE EVENTUAL PHASING OF THE MODIFIED TROPICAL MOISTURE AND UPPER
SYSTEM LOOKS TO SIT AND STEW OVER THE NORTHEAST FOR DAYS AFTER THE
WARM TONGUE EVOLUTION COMPLETES ITSELF...AND THE SYSTEM OCCLUDES
AND DECAYS. AS SUCH...BRISK NORTHWESTERLY FLOW CONTINUES THROUGH
NEXT WEEK...HOWEVER THE LINK TO CANADIAN COLD AIR BASICALLY
BECOMES WEAKER BY THE DAY AFTER MID-WEEK. AS SUCH...P-TYPE SLOWLY
TRENDS BACK TOWARD LIQUID EVERYWHERE EVEN THOUGH TEMPERATURES SEEM
SET TO REMAIN FAR BELOW NORMAL THROUGH THE END OF NEXT WEEK. FRIES
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
JUDGING FROM RECENT SURFACE AND RADAR DADA PLUS GFS LAMP AND RAP
MODEL OUTPUT...CONTINUE TO FORECAST VFR WITH NO LOWER THAN 4 KFT
STRATOCUMULUS CEILINGS THROUGH 00Z...EVEN THOUGH SURFACE WIND
SHIFT TO NORTHWEST DIRECTION COULD REACH KHLG-KPIT-KFKL BEFORE
22Z.
HAVE CONTINUED FORECAST OF ONSET OF MVFR RESTRICTIONS DUE TO POST
FRONTAL BAND OF LOWER BASED CLOUDS WITH SHOWERS DURING THE 00Z TO
06Z TIME FRAME FOR PORTS AS FAR EAST AS KDUJ-KPIT-KHLG.
THE POST FRONTAL MVFR CONDITIONS MAY NOT REACH KLBE AND KMGW UNTIL
DAYTIME SATURDAY.
THE POSTFRONTAL RAIN SHOWERS WILL LIKELY INCREASE IN INTENSITY AND
COVERAGE DAYTIME SATURDAY DUE TO DUE TO ENHANCED BETWEEN THE
COLD FRONT AND A DEVELOPING JET STREAK ALOFT.
SURFACE WINDS AHEAD OF THE COLD FRONT WILL BE FROM
SOUTHEAST...BEHIND THE COLD FRONT FROM THE NORTHWEST. MOST SPEEDS
ABOUT 10 KTS...AND LIKELY NO MORE THAN 15 KTS TONIGHT. WINDS MAY
GUST TO 20 TO 25 KTS SATURDAY AFTERNOON.
.OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
EXPECT FREQUENT IFR RESTRICTIONS DUE TO RAIN THIS PERIOD...AND
POSSIBLY PERIODS OF WET SNOW STARTING LATE MONDAY. WINDS CAN
ALSO IMPACT AVIATION WITH POSSIBLE GUSTS OVER 30 KTS MONDAY AND
TUESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1223 PM EDT FRI OCT 26 2012
.SYNOPSIS...
A SLOWLY MOVING EASTBOUND COLD FRONT WILL HERALD WETTER AND COLDER
CONDITIONS FOR THE UPPER OHIO VALLEY THIS WEEKEND. INTERACTION
BETWEEN THIS STRONG COLD FRONT AND NORTHBOUND HURRICANE SANDY MAY
LEAD TO A PERIOD OF HEAVY RAIN AND WINDY CONDITIONS MONDAY INTO
WEDNESDAY...WITH PERHAPS EVEN SOME SNOWFALL AS WELL.
&&
.NEAR TERM /THROUGH TONIGHT/...
BASED FORECAST THIS PERIOD ON BLEND OF RECENT SREF MODEL OUTPUT
WITH DETAILS FROM RECENT WRF-NMM AND RAP MODEL.
THIS CONTINUE TO
SHOW THE STRONG COLD FRONT AS THE MAIN WEATHER MAKER. DUE TO
RECENT MODEL OUTPUT...HAVE SLOWED PASSAGE OF THE STRONG COLD
FRONT INTO THE I-79 CORRIDOR BY AN HOUR OR SO LATE THIS AFTERNOON
INTO EARLY EVENING...WITH COLD FRONT NOT REACHING THE APPALACHIAN
MOUNTAINS BEFORE SATURDAY MORNING. STILL APPEARS THE BULK OF
SHOWERS WILL BE AFTER THE COLD FRONTAL PASSAGE.,,A S0-CALLED
ANA FRONT SCENARIO. CONTINUED CATEGORICAL RAIN CHANCES LATE TONIGHT
DUE TO EXPECTED ENHANCED FRONTOGENETICAL FORCING ASSOCIATED WITH
INTERACTION BETWEEN THE COLD FRONT AND A PASSING JETSTREAK ALOFT.
DUE TO COLD FRONT LOCATION...THERE CAN BE A 10 DEGREE WEST TO EAST
DIFFERENCE IN HIGH TEMPERATURES THIS AFTERNOON...AS INDICATED BY
RECENT GFS AND NAM MOS. THIS STILL MAKES HIGHS 10 TO 20 DEGREES
WARMER THAN NORMAL.
FORECASTED LOWS UP TO 2 DEGREES COLDER THAN EARLIER
PROJECTIONS...BUT THESE WILL STILL BE WARMER THAN NORMAL.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
THE MODELS CONTINUE TO DIFFER IN THE EVENTUAL INTERACTION OF THE
AFOREMENTIONED COLD CORE TROUGH AND THE ADVANCING SANDY. THIS
MORNINGS SHORT TERM PROGNOSIS WAS BASED ON A BLEND OF PERSISTENCE
WITH THE LATEST NAM...WHICH MOVES SANDY QUICKER UP THE COAST BY 84
HOURS...AND THE GFS...WHICH NOW BUMPS THE COAST ARND NEW YORK WITH
THE STORM ON TUESDAY BEFORE PHASING IT WITH THE TROUGH AND SENDING
IT ASHORE OVER NEW ENGLAND.
THE BOTTOM LINE FOR THE UPPER OHIO REGION IS THAT WIDESPREAD RAIN
IS ANTICIPATED OVER THE AREA AS THE TROUGH/STALLED FRONT IS FUELED
BY DEEP MOISTURE FUNNELED OFF THE ATLANTIC IN ADVANCE OF THE
HURRICANE.
FOR SUNDAY NIGHT AND MONDAY...SHOULD THE GFS TRACK BE CORRECT...COLDER
AIR WILL WRAP OVER THE REGION AND SPAWN A MIX WITH...OR CHANGE TO
SNOW...ESPECIALLY OVER THE HIGHER ELEVATIONS. GIVEN THE FORECAST
OF RELATIVELY WARM BOUNDARY LAYER TEMPERATURES...HAVE RESERVED ANY
INITIAL ACCUMULATION OVER THE RIDGES FOR MONDAY MORNING. THE
WEATHER GRIDS FOR THIS PERIOD WERE CONSTRUCTED USING GFS THICKNESS
PARAMETERS...ALTHOUGH CONFIDENCE IS SOMEWHAT SHAKEY GIVEN THE
REPUTATION OF THE ECMWF MODEL...LATEST SOLUTION OF WHICH STILL
INDICATES A MORE WESTWARD TRACK OF SANDY AND A TROUGH- PHASING
WHICH PLACES A MATURE...STACKED...AND POWERFUL LOW IMMEDIATELY
OVER THE REGION BY TUESDAY. THE RESULTING PROLONGED RAIN TOTALS
WOULD THUS HAVE TO BE ADDRESSED...ESPECIALLY AS THE LEAVES HAVE
DEPARTED AND ANTECEDENT CONDITIONS WILL MORE RAPIDLY SATURATE.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
AT ANY RATE...AS MENTIONED ABOVE...MODEL DISPARITY CONTINUES TO
HAMPER CONFIDENCE LEVELS AS THE LATEST GFS MOVES SANDY OVER NEW
ENGLAND LATER IN THE WEEK AS ITS FINAL SOLUTION. REGARDLESS...BY
MONDAY NIGHT...SUFFICIENTLY COLD AIR IS PROGGED OVER THE REGION
FOR A MIX-WITH OR CHANGE TO SNOW...AND SOME LIGHT ACCUMULATION HAS
BEEN INTRODUCED FOR THE HIGHER ELEVATIONS.
THEREAFTER...NO ALTERATIONS WERE ATTEMPTED TO THE LONG TERM AS AN
AMPLIFIED AND BROAD ERN CONUS UPPER TROUGH WILL MAINTAIN SUB
NORMAL TEMPERATURES ACCOMPANIED BY RAIN AND SNOW SHOWER CHANCES.
&&
.AVIATION /16Z FRIDAY THROUGH TUESDAY/...
VFR FORECAST THROUGH THE DAYLIGHT HOURS.
COLD FRONT IS EXPECTED TO MOVE THROUGH THE REGION LATE THIS
AFTERNOON...STALLING JUST TO THE EAST OF PIT. WINDS WILL SWING
FROM SOUTH TO NORTHWEST WITH THE FRONTAL PASSAGE...WITH SHOWERS
AND MVFR CONDITIONS TRAILING THE FRONT ITSELF. AT THIS
TIME...APPEARS RAIN AND MVFR BEGIN TO AFFECT KZZV THIS
AFTERNOON...BUT WILL HOLD OFF WILL HOLD OFF OR POINTS SUCH AS
KFKL-KPIT-KMGW UNTIL THE EVENING HOURS.
SURFACE WINDS AHEAD OF THE COLD FRONT WILL BE FROM
SOUTHEAST...BEHIND THE COLD FRONT FROM THE NORTHWEST. MOST SPEEDS
ABOUT 10 KTS...AND LIKELY NO MORE THAN 15 KTS.
.OUTLOOK.../SATURDAT THROUGH TUESDAY/...
IFR WEATHER IS LIKELY IN WAKE OF THE COLD FRONT SATURDAY. BRIEF
IFR RESTRICTIONS MAY CONTINUE IN RAIN OR SNOW SHOWERS THROUGH
TUESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
321 PM CDT FRI OCT 26 2012
.DISCUSSION...
TONIGHT AND SATURDAY...SFC HIGH PRES CENTERED OVER NE/KS WILL
CONTINUE TO SHIFT ENE OVERNIGHT THROUGH SATURDAY...CENTERING
ITSELF OVER ERN IA BY LATE DAY SATURDAY. ALOFT...A MODEST MIDLVL
TROUGH AXIS ROUNDING THE BASE OF THE MEAN LONGWAVE TROUGH SET UP
OVER CENTRAL NORTH AMERICA WILL SWING THROUGH THE REGION. AS THIS
TROUGH SWINGS THROUGH...IT WILL TAKE LINGERING STRATUS CLOUD COVER
WITH IT...MAKING FOR MOSTLY CLEAR SKIES DURG THE EARLY MORNING
HOURS. ALTHOUGH CAA IS LESSENING DUE TO A WEAKENING WLY FLOW...
THE CLEARING SKIES WILL ALLOW LOW TEMPS TONIGHT TO PLUMMET TO THE
LOWER 20S FOR MOST OF THE WFO MPX CWFA /WITH THE MAIN EXCEPTION
BEING MID 20S IN THE TWIN CITIES METRO/. AS THE HIGH PRES CENTER
SHIFTS E...A VRBL SFC FLOW WILL MAKE FOR NEGLIGIBLE TEMP
ADVECTION...LEAVING SLIGHTLY WARMER H85 TEMPS AND ADDITIONAL
SUNSHINE TO PRODUCE HIGHS IN THE UPPER 30S TO MID 40S. CLOUDS WILL
BE ON THE INCREASE LATE IN THE DAY AS ANOTHER WEAK TROUGH AXIS
SWINGS THROUGH THE NRN PLAINS ON ITS WAY TWD THE UPPER MISS RIVER
VALLEY.
SATURDAY NIGHT THROUGH MONDAY...THE AFOREMENTIONED TROUGH AXIS
ALOFT WILL BECOME DETACHED FROM A SFC LOW PRES SYSTEM OVER THE
SOUTHWEST...BUT STILL CARRY ENOUGH OF A MOISTURE SWATH TO PRODUCE
SOME -SNSH/-SN OVER NW PORTIONS OF THE CWFA LATE SAT NIGHT INTO
SUN MRNG. ACCUMS LOOK TO BE AROUND AN INCH FOR FAR WRN PORTIONS OF
THE AREA...TRENDING DOWN TO A TRACE WEST OF THE TWIN CITIES. POPS
ARE CAPPED IN THE 40S TO REFLECT ONLY SCATTERED COVERAGE. SOME
FLURRIES MAY LINGER BEYOND DAYBREAK FOR SWRN PORTIONS WHILE THE
CHC FOR -SN CONTINUES IN NW-N PORTIONS. THE TROUGH ALOFT QUICKLY
SHIFTS E BY MIDDAY SUNDAY...KEEPING PARTLY TO MOSTLY CLOUDY SKIES
IN PLACE LATE SUNDAY THRU MOST OF MONDAY. TEMPS WILL CONTINUE TO
RUN BELOW NORMAL THROUGH THE WEEKEND INTO MONDAY.
TUESDAY THROUGH THURSDAY...BENIGN CONDITIONS WITH FAIRLY
CONSISTENT TEMPERATURES WILL PREVAIL DURG THE MIDWEEK PERIOD AS
THE PATTERN WILL CONSIST OF A MASSIVE EAST COAST TROUGH /AS THE
RESULT OF THE MERGER OF HURCN SANDY AND THE ONGOING TROUGH/ AND A
WEST COAST RIDGE. RELATIVELY WEAK N-S ORIENTED HIGH PRESSURE WILL
KEEP WX SYSTEMS FROM AFFECTING THE AREA AND ALSO MITIGATE ANY
STRONG SWINGS IN TEMPERATURE.
&&
.AVIATION.../18Z TAF ISSUANCE/
MAIN PROBLEM REMAINS EXTENT OF CLOUD COVER THIS AFTERNOON/EVENING.
MODEL TRENDS NOW PICK UP ON HIGHER LEVEL HUMIDITY AROUND 4-5K FEET
BUT WITH THE RAP HOLDING ONTO CLOUDS THE LONGEST. WILL CONTINUE
PREVIOUS VFR TREND OF SCATTERING CLOUDS BY EARLY EVENING AS SURFACE
HIGH BUILDS OVER SOUTHERN MN. SOME HIGH CLOUDS THEN INTO SATURDAY
MORNING WEST...THEN LOWERING IN THE AFTERNOON. WESTERLY WINDS A BIT
GUSTY INTO THE AFTERNOON AS GRADIENT GRADUALLY RELAXES OVER THE
SOUTHWEST AREA. LIGHT SOUTHWEST WINDS TONIGHT AND REMAIN BELOW 10
KNOTS FOR SATURDAY.
KMSP...
VFR EXPECTED THROUGH THE PERIOD. EXPECT AT LEAST BKN CLOUDS AROUND
4-5K FT TO REMAIN OVER THE AREA THROUGH 00Z SAT. SHOULD SEE AT
LEAST SCT CLOUDS OVERNIGHT AND THEN HIGHER LEVEL CLOUDS MOVING IN ON
SATURDAY. WEST WINDS GUSTING 20-23KTS DIMINISHING BY EVENING. THEN
SOUTHWEST WINDS INTO SATURDAY...REMAINING LESS THAN 10 KNOTS AND
SLOWLY SHIFTING MORE SOUTHEAST BY LATE SATURDAY AFTERNOON...AHEAD OF
NEXT DEVELOPING TROUGH OVER THE DAKOTAS.
/OUTLOOK FOR KMSP/
SAT...VFR. WINDS LGT AND VRBL.
SUN...MVFR POSSIBLE. SLIM CHANCE OF IFR. CHC -SN IN THE MORNING.
WINDS SE AT 5 KTS.
MON...VFR. WINDS SE AT 5 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
JPC/DWE
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1205 PM CDT FRI OCT 26 2012
.UPDATE...FOR 18Z AVIATION DISCUSSION BELOW
&&
.DISCUSSION.../ISSUED 243 AM CDT FRI OCT 26 2012/
MAIN SHORT TERM CONCERN DEALS WITH CLD CVR TODAY WHICH WILL
CORRELATE TO SOME TEMPERATURE VARIATIONS IF MORE OR LESS STRATO-CU
DEVELOPS. OVER THE PAST TWO HRS...A LARGE CLEARING LINE HAS
DEVELOPED ACROSS CENTRAL AND SOUTHERN MN...ONLY THE FAR NW AND SW
HAD MOSTLY CLOUDY SKIES. LATEST RAP DOES HAVE THIS TYPE OF
SCENARIO OF CLEARING OUT FOR MOST OF THE FA DURING THE EARLY
MORNING HRS...BUT QUICKLY SATURATES UP TO ARND 90H BY 9 AM TO
NOON. WITH A LARGE AREA OF CLDS UPSTREAM...AND THE MEAN FLOW
CONTINUES FROM THE W/NW...WILL LEAD TOWARD CLOUDING UP AGAIN BY
NOON WITH TEMPERATURES CLOSE TO PREVIOUS FORECAST. SOME OF THE RAP
SOUNDINGS INDICATED VERY STEEP LAPSE RATES FROM THE SFC... UP TO
80H WITH CAPES 50 TO 100 J/KG. THE DEPTH OF THE MOISTURE AND
ASSOCIATED HIGHER CAPES OCCUR ACROSS MAINLY THE NE FA. ALTHOUGH
THE CRITICAL TEMPS THAT ARE ASSOCIATED WITH THE DEVELOPMENT OF ICE
CRYSTALS ARE LIMITED FOR MOST OF THE FA...SOME INDICATIONS THAT
THE DEPTH OF THE MOISTURE IN THE N/NE FA COULD ALLOW FOR SOME
-SNSH.
THE WEAK SYSTEM EXPECTED OVER THE WEEKEND HAS WEAKENED EVEN FURTHER
FOR THIS FORECAST PERIOD WHICH MEANS THAT THE CHC OF MEASURABLE
PRECIPITATION WILL BE VERY UNLIKELY. THE MAIN FACTOR IS THE VERY
DRY AIR MASS IN PLACE WHICH WILL TAKE TIME TO SATURATE THE THERMAL
COLUMN THIS WEEKEND. BEST CHC OF MEASURABLE PRECIPITATION WILL
OCCUR IN FAR SW/WC MN WHERE SLIGHTLY BETTER 85-70H DYNAMICS
EXISTS.
PAST THIS WEEKEND...THE OVERALL PATTERN WILL BE HIGHLY DEPENDENT
ON THE EVOLUTION OF HURRICANE SANDY AND HOW IT WILL TRANSLATE
ACROSS THE EASTERN U.S. CURRENT MODELS HAVE THIS SYSTEM MERGING
WITH A SECONDARY STORM SYSTEM MOVING SE ACROSS THE GREAT
LAKES/OHIO VALLEY OVER THE WEEKEND. CURRENT TRENDS HAVE THE
HURRICANE OR REMNANTS OF THIS TROPICAL SYSTEM...MOVING ONSHORE
NEAR THE NEW JERSEY/DELAWARE STATE LINE. AS THESE SYSTEMS
COMBINE...A VERY LARGE STORM IS EXPECTED TO SLOWLY MOVE FROM THE
MID ATLANTIC REGION...N/NW TO THE EASTERN GREAT LAKES. THIS WOULD
LEAD TO THE CONTINUED N/NW FLOW ACROSS THE UPPER MIDWEST.
BASICALLY THIS IS A DRY AND COOL PATTERN FOR OUR REGION. ..JLT..
&&
.AVIATION.../18Z TAF ISSUANCE/
MAIN PROBLEM REMAINS EXTENT OF CLOUD COVER THIS AFTERNOON/EVENING.
MODEL TRENDS NOW PICK UP ON HIGHER LEVEL HUMIDITY AROUND 4-5K FEET
BUT WITH THE RAP HOLDING ONTO CLOUDS THE LONGEST. WILL CONTINUE
PREVIOUS VFR TREND OF SCATTERING CLOUDS BY EARLY EVENING AS SURFACE
HIGH BUILDS OVER SOUTHERN MN. SOME HIGH CLOUDS THEN INTO SATURDAY
MORNING WEST...THEN LOWERING IN THE AFTERNOON. WESTERLY WINDS A BIT
GUSTY INTO THE AFTERNOON AS GRADIENT GRADUALLY RELAXES OVER THE
SOUTHWEST AREA. LIGHT SOUTHWEST WINDS TONIGHT AND REMAIN BELOW 10
KNOTS FOR SATURDAY.
KMSP...
VFR EXPECTED THROUGH THE PERIOD. EXPECT AT LEAST BKN CLOUDS AROUND
4-5K FT TO REMAIN OVER THE AREA THROUGH 00Z SAT. SHOULD SEE AT
LEAST SCT CLOUDS OVERNIGHT AND THEN HIGHER LEVEL CLOUDS MOVING IN ON
SATURDAY. WEST WINDS GUSTING 20-23KTS DIMINISHING BY EVENING. THEN
SOUTHWEST WINDS INTO SATURDAY...REMAINING LESS THAN 10 KNOTS AND
SLOWLY SHIFTING MORE SOUTHEAST BY LATE SATURDAY AFTERNOON...AHEAD OF
NEXT DEVELOPING TROUGH OVER THE DAKOTAS.
/OUTLOOK FOR KMSP/
SAT...VFR. WINDS LGT AND VRBL.
SUN...MVFR POSSIBLE. SLIM CHANCE OF IFR. CHC -SN IN THE MORNING.
WINDS SE AT 5 KTS.
MON...VFR. WINDS SE AT 5 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
JLT/DE
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1225 PM CDT FRI OCT 26 2012
.AVIATION...18Z TAF. FORECAST CONTINUES TO BE A CHALLENGE DUE TO
THE MODELS NOT HANDLING THE STRATUS VERY WELL. MOST OF THE MODELS
HAVE HAD LITTLE TO NO STRATUS AND THOSE THAT DO KEEP IT IN. HAVE
BASED THE LATEST FORECAST ON WHAT IS UP STREAM AT THIS TIME.
CURRENTLY THERE IS MID/HIGH LEVEL CLOUDS AROUND THE AREA BUT TO
THE NORTHWEST OF THE KGRI TERMINAL IN THE KODX AND KBBW AREAS
THERE IS SOME LOWER CLOUDS THAT ARE STILL VFR. FURTHER TO THE
NORTHWEST THERE ARE SOME MVFR CLOUDS AND WILL BRING THEM IN A
LITTLE LATER TONIGHT. BELIEVE THAT THESE WILL BE LIFTING SOME AS
MORNING APPROACHES. WITH A SURFACE HIGH ACROSS THE AREA WINDS WILL
BE LIGHT TONIGHT THEN TURN TO THE SOUTH TOMORROW.
&&
.PREV DISCUSSION... /ISSUED 333 AM CDT FRI OCT 26 2012/
SHORT TERM...TODAY THROUGH SUNDAY NIGHT. A COOLER PATTERN WILL BE
IN PLACE ACROSS THE CENTRAL PLAINS INTO THE WEEKEND UNDER THE
INFLUENCE OF AN UPPER TROUGH FM MANITOBA/ONTARIO ACROSS THE
NORTHERN/CENTRAL PLAINS. A 1033MB SURFACE HIGH WILL BUILD
SOUTHEAST FM MT/WY INTO NEBRASKA TODAY WITH LITTLE CHANGE IN THE
COLDER AIRMASS IN PLACE ACROSS OUR AREA. STRATUS CLOUDS HAVE
EXPANDED ACROSS CENTRAL NEBRASKA/NORTHERN KANSAS DURING THE PRE
DAWN HOURS...AND THIS CLOUD COVER HAS NOT BEEN HANDLED WELL BY MODELS.
PER SATELLITE IMAGERY...SOME CLEARING HAS COMMENCED ACROSS EASTERN
NEBRASKA INTO FAR NORTHEAST KANSAS AND HRRR PROGS SUGGEST THE
CLEARING MAY REACH OUR EAST/NORTHEAST COUNTIES...WHILE THE LOWER
CLOUDS MIGRATE TO THE SOUTHWEST. HAVE TO ADMIT CONFIDENCE IS NOT
HIGH ON EXTENT OF CLOUD COVER TODAY WHICH WILL ULTIMATELY HAVE AN
IMPACT ON OUR HIGH TEMPERATURES. BELIEVE ITS BEST TO KEEP THINGS
CONSERVATIVE AND WILL PLACE MAX TEMPS AROUND 40F IN NEB/LOW 40S IN NC
KANSAS. THE CLOUDS LOOK TO SCATTER TONIGHT...BEFORE INCREASING
AGAIN ON SATURDAY AHEAD OF NEXT APPROACHING WAVE. IN DECREASING
CLOUDS...DRIER/COLD AIRMASS WE ARE LOOKING AT ANOTHER COLD NIGHT
WITH LOW TEMPS WELL BELOW FREEZING.
SATURDAY THE FORECAST TURNS A LITTLE MORE INTERESTING AS 125KT H3
JET PROGRESSES SOUTHEAST IN NORTHWEST FLOW/ON BACK SIDE OF TROUGH
WITH DIVERGENCE ALOFT INCREASING IN OUR NORTHERN CWA IN LFQ OF JET.
A DECENT H7 SHORTWAVE TROUGH CROSSES NORTHERN/CENTRAL NEBRASKA IN
THE AFTN. WAA INCREASES AHEAD OF APPROACHING WAVE WITH ISENTROPIC
LIFT NOTED IN AFTN ON THE 290K SFC ACROSS OUR NORTHERN ZONES.
FORECAST SOUNDINGS INDICATE MOISTURE LACKING BELOW H75 SO NOT
LOOKING FOR MUCH IN THE WAY PCPN ATTM...BUT CANNOT RULE OUT
SPRINKLES AND WILL ADD IN POTENTIAL FOR VALLEY/GREELEY COUNTIES.
MID LEVEL SHORTWAVE TROUGH AXIS PASSES SATURDAY NIGHT AND HEIGHTS
GRADUALLY BEGIN TO RISE ON SUNDAY. LLVL FLOW REMAINS WEAK AS SFC
RIDGE SLOWLY TREKS EAST AND MODELS INDICATE POTENTIAL FOR
INCREASING MID/HIGH CLOUDS. NOT LOOKING AT MUCH WARMING JUST
YET...WITH HIGHS IN THE MID/LOW 50S. THE COOLER AIRMASS SHIFTS
EAST OF THE MISSOURI RIVER SUNDAY NIGHT WITH TEMPS MODERATING MORE
SO HEADING INTO THE WORKWEEK.
LONG TERM...MONDAY THROUGH THURSDAY. WHILE THE EVOLUTION OF
HURRICANE SANDY AND THE EXTENT OF EAST COAST IMPACTS WILL GARNER THE
BRUNT OF NATIONAL ATTENTION NEXT WEEK...IT STILL APPEARS THE CENTRAL
PLAINS WILL QUIETLY EXPERIENCE SEVERAL DAYS OF DRY...TRANQUIL...AND
SEASONABLY MILD CONDITIONS INCLUDING HALLOWEEN. ANY CHANGES TO THE
PREVIOUS FORECAST...IF ANY AT ALL DURING PERIODS...WERE VERY MINOR AND
PRIMARILY INVOLVED A VERY SLIGHT 1-2 DEGREE UPWARD NUDGE IN DAILY
HIGH TEMPERATURES. IN GENERAL...DAILY HIGHS ARE FORECAST TO BE
WITHIN A FEW DEGREES EITHER SIDE OF NORMALS...SO ALL IN ALL TYPICAL
MID-FALL WEATHER.
STARTING WITH MONDAY/MONDAY NIGHT...AGREEMENT BETWEEN THE 00Z
ECMWF/GFS SOLUTIONS IS FAIRLY SIMILAR...ALTHOUGH THE EC SUGGESTS A
BIT STRONGER MID LEVEL RIDGE WILL EDGE TOWARD THE AREA WHILE BECOMING
CENTERED ALONG AN AXIS FROM THE DESERT SOUTHWEST TO THE NORTHERN
ROCKIES...WHILE THE GFS WHICH IS FARTHER EAST WITH SANDY KEEPS MORE
OF A BROAD NORTHWEST FLOW INTACT OVER THE REGION. HOWEVER...EVEN THE
GFS SOLUTION KEEPS ANY CLIPPER-TYPE SHORTWAVE SYSTEMS AND ASSOCIATED
MINOR PRECIPITATION EVENTS NO CLOSER THAN A CORRIDOR FROM SOUTH
DAKOTA THROUGH IA. HIGH TEMPS ARE FORECAST TO RANGE MID 50S
NORTHEAST TO LOW 60S SOUTHWEST...WITH OVERNIGHT LOWS MAINLY
MID-UPPER 30S.
TUESDAY/TUESDAY NIGHT...OVERALL VERY LITTLE CHANGE AS THE DEEP
TROUGH ASSOCIATED WITH SANDY DOMINATES THE EASTERN CONUS...WHILE THE
CENTRAL PLAINS REMAINS UNDER NORTH-NORTHWEST FLOW ON THE EASTERN
PERIPHERY OF THE ROCKY MOUNTAINS RIDGE AXIS. HIGH TEMPS ARE
ADVERTISED VERY SIMILAR TO MONDAY...RANGING MID 50S NORTHEAST TO MID
60S SOUTHWEST.
WEDNESDAY/WEDNESDAY NIGHT...THE BLOCKING PATTERN REMAINS FIRMLY IN
PLACE...AS THE MID LEVEL RIDGE AMPLIFIES EVEN MORE OVER THE CENTRAL
CONUS IN BETWEEN THE EASTERN TROUGH AND THE NEXT UPSTREAM TROUGH
MOVING ONTO THE PACIFIC COAST. BARRING MAJOR CHANGES...HALLOWEEN
WEATHER CONDITIONS DON/T GET MUCH MORE TRANQUIL THAN THIS...WITH
AFTERNOON HIGHS RANGING UPPER 50S NORTHEAST TO MID 60S
SOUTHWEST...AND EVENING READINGS SETTLING INTO THE 40S FOR
TRICK-OR-TREATERS.
THURSDAY...THE HEART OF THE EXPANSIVE NORTH-SOUTH MID LEVEL RIDGE
AXIS SHOULD EDGE EAST A BIT MORE TOWARD THE CENTRAL PLAINS FROM THE
ROCKIES...AS THE UPSTREAM WEST COAST WAVE FINALLY STARTS MAKING A
BIT OF EASTWARD PROGRESS. YET AGAIN FORECAST HIGH TEMPS ARE ALMOST
IDENTICAL TO THE PREVIOUS DAY...RANGING UPPER 50S NORTHEAST TO MID
60S SOUTHWEST ACROSS THE CWA.
LOOKING BEYOND THE OFFICIAL FORECAST PERIOD...THE NEXT HALFWAY
DECENT CHANCE OF PRECIPITATION...AND LIKELY IN THE FORM OF RAIN AND
NOT SNOW...SHOULD ARRIVE GENERALLY DURING THE NEXT FRIDAY
NIGHT-SATURDAY TIME FRAME AS THE WESTERN TROUGH FINALLY TRACKS INTO
THE PLAINS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
333 PM CDT FRI OCT 26 2012
.DISCUSSION.../ISSUED AT 333 PM CDT/
BIGGEST CHALLENGE TONIGHT WILL AGAIN BE WHEN/IF STRATUS DISSIPATES
ACROSS THE AREA. PER LATEST SATELLITE IMAGE...PRESENTLY SEEING THE
ENTIRE CWA SOCKED IN WITH CLOUDS...WITH SOME BREAKS OVER NORTH
CENTRAL AND NORTHEASTERN SOUTH DAKOTA. MODELS STILL NOT HANDLING THE
LOW LEVEL RH FIELDS VERY WELL...ALTHOUGH THE RAP SEEMS TO HAVE BEEN
DOING THE BEST SINCE YESTERDAY AFTERNOON. IN LIGHT OF THAT...WENT
WITH THAT MODEL FOR LOW LEVEL CLOUDS THIS EVENING...WITH THEM
BEGINNING TO BREAK UP BY 06Z TONIGHT. THE CLOUD COVER WILL HAVE A
BIG IMPACT ON LOW TEMPERATURES...AND WITH WINDS GOING LIGHT AS A
SURFACE RIDGE SLIDES OVERHEAD...ANY CLEARING WILL ALLOW READINGS TO
DROP DOWN INTO THE LOWER 20S NORTH AND EAST. IT WILL REMAIN A LITTLE
WARMER IN THE SOUTHWEST HOWEVER...WITH MID AND HIGH CLOUDS EXPECTED
TO STREAM INTO THAT AREA LATER IN THE NIGHT OUT AHEAD OF THE NEXT
SYSTEM. HOWEVER...IF CLOUDS REMAIN THROUGHOUT MOST OF THE AREA
TONIGHT...LOWS WILL BE WARMER THAN CURRENTLY FORECASTED AND THE
EVENING SHIFT MAY HAVE TO UPDATE.
ON SATURDAY...CLOUDS WILL INCREASE ACROSS THE AREA EARLY IN THE
DAY...ASSUMING WE EVEN GET ANY CLEARING TONIGHT...AS A SHORTWAVE
APPROACHES FROM THE WEST BY AFTERNOON. DOES APPEAR NOW THAT MUCH OF
ANY PRECIPITATION THAT DEVELOPS WITH THE SYSTEM WILL HOLD OFF UNTIL
LATER AFTERNOON. WHILE PROGGED 850 MB TEMPS ARE PROGGED TO BE BELOW
0 C...BUFKIT SOUNDINGS SHOW A WARMER LAYER FROM AROUND 900 MB TO THE
SURFACE...AND THINK THAT EVEN COOLING TO WET BULB WILL KEEP A
RAIN/SNOW MIX IN THE AFTERNOON IF PRECIPITATION DEVELOPS. WITH
WARMING 925 MB TEMPERATURE PROFILES...HIGHS WILL BE A LITTLE WARMER
ON SATURDAY...THOUGH STILL WELL BELOW NORMAL FOR THIS TIME OF
YEAR...IN THE LOWER 40S NORTH TO MID/UPPER 40S FAR SOUTH.
SHORT WAVE TROUGH IS EXPECTED TO TRACK INTO THE EASTERN HALF OF THE
FORECAST AREA SATURDAY NIGHT WHILE THE WEAK INVERTED SURFACE TROUGH
LIFTS NORTH NORTHEAST INTO SOUTHERN MINNESOTA BY DAYBREAK SUNDAY.
LIGHT PRECIPITATION WILL BE LIKELY AS IT SPREADS EAST INTO OUR
WESTERN CWA IN THE EVENING. WITH TEMPERATURES DROPPING NEAR FREEZING
AROUND SUNSET...LIGHT RAIN AND SNOW WILL TRANSITION TO SNOW AND
BECOME SCATTERED AFTER MIDNIGHT AS THE INVERTED TROUGH LIFTS
NORTHEASTWARD AND ENCOUNTERS DRIER LOWER LEVELS. SNOWFALL AMOUNTS
WILL BE AROUND A HALF IN OR LESS FOR MOST AREAS...WITH POTENTIALLY
UP TO AN INCH IN EAST CENTRAL SOUTH DAKOTA AND LITTLE TO NO
ACCUMULATION IN NORTHWEST IOWA.
MODELS INDICATE THAT THE STRATUS COULD LINGER ACROSS THE AREA INTO
SUNDAY...PARTICULARLY IN THE EASTERN HALF WHERE MODELS HINT AT SOME
LINGERING FLURRIES NEAR OUR FAR EASTERN BORDER COULD STICK AROUND
INTO MID MORNING. CLOUDS MAY BE HARD TO CLEAR EVEN IN THE
AFTERNOON...SO HAVE LEFT MOSTLY OR PARTLY CLOUDY SKIES. HIGHS WILL
BE IN THE 40S. LOWS ON SUNDAY NIGHT WILL BE LARGELY DEPENDENT ON
WHETHER WE HOLD ONTO THE CLOUDS...BUT WITH SOME CLOUD COVERAGE
EXPECTED...WILL GO WITH SOME MIDDLE GROUND LOWS NEAR OR JUST BELOW
FREEZING.
FOR THE EXTENDED...IT LOOKS LIKE LARGE SCALE NORTHWEST FLOW WILL BE
LOCKED IN PLACE THROUGH MID TO LATE WEEK ACROSS THE NORTHERN AND
CENTRAL PLAINS AS HURRICANE SANDY HEADS INTO THE MID ATLANTIC AND
NEW ENGLAND STATES. TEMPERATURES WILL BE ON A VERY SLOW WARMING
TREND THROUGH THE PERIOD WITH THE RIDGE AXIS TO OUR WEST GRADUALLY
SHIFTING INTO THE PLAINS. MODELS STILL NOT IN TOTAL AGREEMENT WITH
THE TRACK OF SANDY...BUT FOR OUR NECK OF THE WOODS...THESE
DISCREPANCIES ONLY RESULT IN SOME SLIGHT WIND AND TEMPERATURE
DIFFERENCES. DID BUMP UP TEMPERATURES A FEW DEGREES FROM ALLBLEND
FOR WEDNESDAY THROUGH FRIDAY. THE OVERALL PATTERN STILL LOOKS DRY
INTO FRIDAY.
&&
.AVIATION.../FOR THE 18Z TAF ISSUANCE/
LOW CLOUD DECK LOOKS TO REMAIN ACROSS THE AREA AT LEAST INTO THIS
EVENING...AND EXPECT CEILINGS TO BE WITHIN THE LOWER VFR RANGE.
CONFIDENCE IS LOW WITH REGARD TO WHETHER CEILINGS WILL BREAK UP
TONIGHT WITH MODELS HANDLING LOW LEVEL RELATIVE HUMIDITY FIELDS
POORLY. SOMEWHAT GUSTY NORTHWESTERLY WINDS TODAY WILL DROP OFF THIS
EVENING...BECOMING VARIABLE TRENDING TOWARD SOUTHERLY OVERNIGHT.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1220 PM CDT FRI OCT 26 2012
.DISCUSSION.../ISSUED AT 1040 AM CDT/
BIGGEST CHALLENGE TODAY REMAINS TO BE CLOUD COVER ACROSS THE AREA.
CURRENT SATELLITE IMAGE SHOWING MUCH OF THE REGION SOCKED IN WITH
STRATUS. THE RUC CONTINUES TO LOOK LIKE THE MODEL OF CHOICE WITH
REGARD TO LOW LEVEL RH FIELDS...SO FOLLOWED THIS IN KEEPING CLOUDS
OVER THE AREA THROUGH AT LEAST LATE THIS AFTERNOON OR EVENING. WITH
THE THOUGHT THAT LITTLE SUNSHINE WILL BE REALIZED...LOWERED HIGHS A
DEGREE OR TWO. UPDATES OUT.
&&
.AVIATION.../FOR THE 18Z TAF ISSUANCE/
LOW CLOUD DECK LOOKS TO REMAIN ACROSS THE AREA AT LEAST INTO THIS
EVENING...AND EXPECT CEILINGS TO BE WITHIN THE LOWER VFR RANGE.
CONFIDENCE IS LOW WITH REGARD TO WHETHER CEILINGS WILL BREAK UP
TONIGHT WITH MODELS HANDLING LOW LEVEL RELATIVE HUMIDITY FIELDS
POORLY. SOMEWHAT GUSTY NORTHWESTERLY WINDS TODAY WILL DROP OFF THIS
EVENING...BECOMING VARIABLE TRENDING TOWARD SOUTHERLY OVERNIGHT.
&&
.PREV DISCUSSION.../ISSUED AT 336 AM CDT/
MAIN FORECAST PROBLEM TODAY WILL BE THE CLOUD COVER. MODELS HAVE
HANDLED THE LOW CLOUD COVER VERY POORLY. DRIER H85 AIR OVER MN AND
IOWA HAVE BROUGHT SOME CLEARING TO SECTIONS OF NORTHWEST IOWA AND
THIS DRIER AIR IS PROGGED TO BACK WEST TO NEAR I29 THIS
MORNING...AND THEN INCREASE AGAIN DURING THE AFTERNOON FROM THE
WEST. SO WILL LIKELY SEE MORE SUNSHINE EAST OF I29 TODAY WHILE
WESTERN CWA REMAINS MOSTLY CLOUDY. HOW FAR WEST ANY CLEARING GETS
TODAY IS AN ISSUE. AS FAR WEST AS I29 MAY BE OPTIMISTIC BASED ON
CURRENT TRENDS MOST AREAS WILL LIKELY STAY MOSTLY CLOUDY THROUGH THE
DAY WITH SOME CLEARING DURING THE NIGHT. WILL BE ANOTHER COLD DAY
WITH HIGHS ONLY IN THE UPPER 30S TO MID 40S.
FOCUS THEN SHIFTS TO SATURDAY AND WAVE DROPS SOUTHEAST IN NORTHWEST
FLOW ALOFT. ASSOCIATED WEAK INVERTED TROF MOVES INTO WESTERN CWA
SATURDAY AND THEN WEAKENS SATURDAY NIGHT. AM EXPECTING SOME LIGHT
PRECIPITATION TO DEVELOP ACROSS WESTERN CWA SATURDAY IN THE FORM OF
LIGHT RAIN OR LIGHT SNOW. THIS PRECIPITATION MAY HAVE A HARD TIME
GETTING MUCH FURTHER EAST OF I29 SATURDAY NIGHT AS SOMEWHAT OF A
KEEWATIN HIGH KEEPS LOWER LEVELS DRY TO THE EAST OF I29 AND THUS
WILL BE HARD TO SATURATE LOW LEVELS AS WEAK WAVE MOVES EAST OF I29
LATER SATURDAY NIGHT. SO WILL KEEP HIGHEST PRECIPITATION CHANCES
WEST OF I29 SATURDAY NIGHT WITH ONLY A CHANCE OF LIGHT SNOW TO THE
EAST. COULD SEE AN INCH OR SO OF SNOW WEST OF I29 SATURDAY LIGHT
WITH PERHAPS LITTLE IF ANY SNOW TO THE EAST. WITH INCREASING CLOUD
COVER AND LOW LEVEL COLD SOUTHEAST FLOW...HIGH TEMPERATURES WILL
STRUGGLE TO CLIMB THROUGH THE 40S...ALTHOUGH HIGHS COLD TOP NEAR 50
ALONG THE MISSOURI RIVER.
AS SYSTEM PULLS AWAY...CWA IS LEFT IN LOW LEVEL SOUTHEAST FLOW AND
CLOUD COVER ON SUNDAY MAY BE HARD TO CLEAR AS STRATUS MAY BE FAIRLY
WIDESPREAD AGAIN. DRIER AIR DOES MOVE INTO WESTERN CWA DURING THE
DAY...BUT THE QUESTION IS IF THIS WILL BE ENOUGH TO SCOUR OUT LOWER
CLOUDS. FOR NOW WILL BE A LITTLE MORE PESSIMISTIC AND ONLY HAVE
SKIES BECOME PARTLY CLOUDY ACROSS THE WEST. TEMPERATURES WILL REMAIN
COLD WITH HIGHS AGAIN ONLY IN THE 40S MOST PLACES.
BELOW NORMAL TEMPERATURES WILL PERSIST ON MONDAY WITH BLOCKING
PATTERN OFF EAST COAST KEEPS COOLER AIR FUNNELING SOUTHEAST ACROSS
CWA.
TUESDAY AND WEDNESDAY SHOULD BE A BIT WARMER...BUT THAT WILL BE
DEPENDENT ON HOW STORM OFF EAST COAST EVOLVES. WITH RETROGRADING
LOW...COOLER TEMPERATURES LIKELY TO REMAIN IN PLACE ACROSS THE CWA
AND NOT AS PROGRESSIVE EAST AS MODEL MAY INDICATE. SO NOT
SIGNIFICANTLY WARMER MONDAY TUESDAY THROUGH THURSDAY. WILL LEAVE
FORECAST DRY AFTER SATURDAY NIGHT...BUT A WEAK WAVE DROPPING
SOUTHEAST TUESDAY COULD PRODUCE SOME LIGHT RAIN...MAINLY OVER
WESTERN CWA AS HIGH PRESSURE OVER THE WESTERN GREAT LAKES REGION
BLOCKS PROGRESSION FURTHER EAST.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
245 PM CDT FRI OCT 26 2012
.SHORT TERM...TONIGHT THROUGH MONDAY NIGHT
245 PM CDT FRI OCT 26 2012
MAIN FORECAST CONCERNS THIS PACKAGE...OCCASIONAL CLOUDS AND
TEMPERATURES THROUGH THE PERIOD.
18Z DATA ANALYSIS HAD LOW PRESSURE CENTERED OVER HUDSONS BAY AND
HIGH PRESSURE CENTERED OVER NEB/KS. MDT PRESSURE GRADIENT OVER THE
REGION BETWEEN THE TWO WITH WEST TO NORTHWEST WINDS OF 10-20MPH AND
GUSTY COMMON ACROSS MN/IA/WI. VIS IMAGERY/SFC OBS SHOWING A BROAD
AREA OF STRATO-CU AROUND 4K FT ADVECTING EAST/SOUTHEAST ACROSS THE
REGION. DIURNAL WARMING/MIXING PRODUCING A SLOW THINNING/BREAKING OF
THE CLOUD DECK. THESE CLOUDS AND SFC-850MB NORTHWEST WINDS PRODUCING
CONTINUED WEAK TO MDT LOW LEVEL COLD ADVECTION ACROSS THE REGION
TODAY...WITH EARLY AFTERNOON TEMPS STRUGGLING TO REACH THE MID 30S
TO MID 40S OVER MOST OF THE REGION.
INITIALIZATIONS OF 26.12Z MODELS LOOKED GOOD. SOLUTIONS QUITE
SIMILAR FOR TONIGHT INTO MON NIGHT...EXCEPT FOR THE HANDLING OF A
WEAK SHORTWAVE TO MOVE ACROSS THE REGION ON SUN...NAM/GEM REMAIN
WETTER WITH THIS FEATURE. DIFFERENCES PERSIST TOWARD THE END OF THE
PERIOD WITH THE HANDLING OF TROPICAL SYSTEM SANDY...THOUGH MUCH
LESS SO THAN THE RUNS OF 25.12Z AND 26.00Z. DPROG/DT OF 500MB HGTS
AT 26.12Z SHOWED MODEL RUNS OF 24.12Z AND 25.12Z VERIFIED QUITE WELL
ACROSS NOAM/EASTERN PAC WITH GFS SHOWING THE BETTER RUN-TO-RUN
CONSISTENCY. RATHER TIGHT CONSENSUS SEEN AMONG THE MODELS THRU SUN
NIGHT...EVEN WITH SANDY AS IT LIFTS NORTH. ECMWF HAS TRENDED CLOSER
TO OTHER MODELS WITH SANDY SUN/SUN NIGHT...NOT APPEARING AS SO MUCH
OF A WESTERN OUTLIER. CONSENSUS IMPROVING MON/MON NIGHT WITH
EVOLUTION OF THE EASTERN CONUS TROUGH/LOW...TRENDING TOWARD A
COMPROMISE OF THE EARLIER RUNS AS SANDY AND THE EASTERN CONUS TROUGH
MERGE AND FORM A BROAD MID LEVEL LOW NEAR THE MID ATLANTIC COAST.
CHECK OF OBS VS. MODEL DATA AT 18Z SHOWED ALL MODELS QUITE GOOD WITH
THE SFC MASS FIELDS OVER THE CENTRAL CONUS. PER WV IMAGERY MODELS
APPEARED GOOD WITH THE SHORTWAVE DETAILS OVER NOAM AND WITH SANDY.
NO CLEAR MODEL FAVORITE AND WITH THE TREND TOWARD A COMPROMISE OF
THE EARLIER RUNS /EVEN ON SANDY IN THE 60-84HR TIME-FRAME/...FAVORED
THE MODEL/ENSEMBLE CONSENSUS. SHORT TERM FCST CONFIDENCE REMAINS
GOOD THIS CYCLE.
FOR THE SHORT TERM...STRATO-CU CLOUD DECK REMAINS PROBLEMATIC
TONIGHT WITH IMPACTS ON LOW TEMPS ACROSS THE AREA. MODELS HANG ONTO
60-80 PERCENT RH IN THE 925-850MB LAYER TONIGHT...TRAPPED UNDER AN
INVERSION NEAR 850MB. CLOUDS HAVE HELD TOUGH OVER MUCH OF MN...
NORTHWEST WI/IA TODAY. WITH NORTHWEST LOW LEVEL FLOW EXPECTED TO
ADVECT THESE CLOUDS SOUTHEAST TONIGHT. WEAK SUBSIDENCE INDICATED AT
850MB...BUT AGAIN A RATHER STRONG INVERSION NEAR 850MB. RAISED SKY
COVER IN GRIDS THRU THE NIGHT...HOLDING ONTO AT LEAST PARTLY CLOUDY
SKIES. SFC RIDGE AXIS BUILDS OVER THE AREA TONIGHT...FOR LIGHT/
VARIABLE WINDS BY MORNING. LOWS TONIGHT LIKELY TO BE QUITE
VARIABLE...QUITE COOL IN AREAS WERE SKIES END UP CLEAR AFTER
MIDNIGHT...TO AS MUCH AS 10-15F WARMER IN AREAS WERE CLOUDS REMAIN.
MODELS SHOW THE 925-850MB MOISTURE TO GRADUALLY DECREASE ON SAT...
BUT HIGH LEVEL MOISTURE/CLOUDS AHEAD OF THE NEXT SHORTWAVE DROPPING
SOUTHEAST THRU THE FLOW ALREADY SPREADS EAST ACROSS THE AREA DURING
THE AFTERNOON. INCREASED CLOUD COVER ON SAT. MID LEVEL MOISTURE WITH
THIS SHORTWAVE SPREADS ACROSS THE FCST AREA FOR SAT NIGHT/SUN AS THE
MAIN SHORTWAVE DROPS INTO THE MID MS VALLEY SAT NIGHT THEN THE
TROUGH AXIS MOVES ACROSS THE AREA SUNDAY. BULK OF THE STRONGER
FORCING/LIFT AND 925-700MB MOISTURE/SATURATION REMAIN WEST/NORTH OF
THE FCST AREA. GIVEN THIS...LEFT SAT NIGHT/SUN DRY BUT CONTINUED
PARTLY TO MOSTLY CLOUDY SKIES OVER THE AREA.
DECENT CONSISTENCY AMONG MODELS FOR ANOTHER WEAK SHORTWAVE AND SURGE
OF MID TO HIGH LEVEL MOISTURE/CLOUDS TO DROP SOUTHEAST ACROSS THE
REGION SUN NIGHT/MON. EVEN WITH THE SFC-850MB RIDGING TO REMAIN OVER
OR NEAR THE AREA INTO MON NIGHT...PARTLY CLOUDY SKIES LOOKING TO BE
THE RULE THRU MON NIGHT.
THROUGH ALL THIS...850MB TEMPS REMAIN BELOW OR NEAR 0C THRU MON
NIGHT..0.5 TO 1.5 STANDARD DEVIATIONS BELOW NORMAL. LOWS/HIGHS FOR
TONIGHT THRU MON NIGHT LOOKING TO BE 5-10F BELOW NORMAL. DUE TO THE
UNCERTAINTIES WITH CLOUD COVER ANY ONE PERIOD...DID NOT STRAY FAR
FROM THE MODEL/ENSEMBLE CONSENSUS FOR LOWS/HIGHS TONIGHT THRU MON
NIGHT...WHICH ALREADY LOOKED WELL TRENDED.
.LONG TERM...TUESDAY THROUGH FRIDAY
245 PM CDT FRI OCT 26 2012
MEDIUM RANGE MODEL RUNS OF 26.00Z/26.12Z IN REASONABLE AGREEMENT
ACROSS THE UPPER MIDWEST TUE...IMPACTED BY WHAT HAPPENS WITH THE
TIMING/PHASING OF SANDY INTO THE EASTERN CONUS TROUGH. 26.12Z ECMWF
FLINCHED AND IS NOW MORE IN LINE WITH CONSENSUS OF OTHER MODELS/
ENSEMBLES ON TUE. IMPACTS OF THE EASTERN CONUS SYSTEM ON THE UPPER
MIDWEST TUE ARE HOW CLOSE THE NORTH-CENTRAL CONUS RIDGING IS TO THE
REGION AND IF WESTERN FRINGES OF THE BROAD LOW WILL REACH THE AREA.
26.12Z GEM NOW THE MOST WESTERLY SOLUTION ON THE SFC-MID LEVEL LOW
TUE/WED. EVEN WITH THE DIFFERENCES TUE/WED...RATHER GOOD CONFIDENCE
THAT TUE-FRI WILL BE A COOL/DRY PERIOD. MODEL CONSENSUS HAS THE
UPPER MIDWEST REMAINING UNDER DRY/COOL NORTHWEST/NORTH FLOW ALOFT
AND A SFC HIGH PRESSURE RIDGE AXIS OVER OR JUST WEST OF THE AREA.
850MB TEMPS START OUT THE PERIOD 0.5 TO 1.5 STANDARD DEVIATIONS
BELOW NORMAL.../0C TO -5C/...SLOWLY WARMING TO AROUND NORMAL /-1C TO
+3C/ BY THE END OF THE PERIOD. PRECIPITABLE WATER VALUES REMAIN
BELOW TO NEAR NORMAL AS WELL. MODEL CONSENSUS DATA IN THE DAY 4-7
FCST GRIDS FOR MINIMAL RAIN/SNOW CHANCES AND TEMPS SLOWLY MODERATING
TOWARD NORMAL LOOK WELL TRENDED.
&&
.AVIATION...THROUGH 18Z SATURDAY
1210 PM CDT FRI OCT 26 2012
SATELLITE AND OBSERVATIONS SHOW A LARGE AREA OF STRATOCUMULUS
SPREADING ACROSS THE REGION. CLOUD DECK HAS ALREADY MOVED OVER
BOTH TAF SITES WITH VFR CEILINGS. LOOKING AT THE 26.15Z RAP AND
26.12Z NAM...IT APPEARS THESE CLOUDS WILL BE HERE FOR A WHILE. THE
BUFKIT SOUNDINGS FROM THE NAM SHOW THIS MOISTURE IS UNDERNEATH AN
INVERSION THAT STARTS AROUND 850 MB AND THIS INVERSION IS EXPECTED
TO REMAIN IN PLACE THROUGH 18Z SATURDAY. BASED ON THIS...WILL SHOW
BOTH TAF SITES KEEPING THE VFR CEILING THROUGH THE PERIOD. THE ONE
CHANCE FOR THE CLOUDS TO DISSIPATE OVERNIGHT RESTS WITH AN OPEN
AREA IN THE CLOUDS OVER NORTH DAKOTA. IF THIS AREA CAN START TO
EXPAND DURING THE NIGHT...IT MIGHT BE ABLE TO REACH THE REGION AND
CLEAR THINGS OUT AND THE EVENING SHIFT WILL NEED TO MONITOR THIS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
245 PM CDT FRI OCT 26 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RRS
LONG TERM....RRS
AVIATION.....04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1210 PM CDT FRI OCT 26 2012
.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
301 AM CDT FRI OCT 26 2012
MAIN FORECAST CONCERNS ARE ON SKY COVER TODAY AND TEMPERATURES
THROUGHOUT.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING OVER THE EASTERN PACIFIC...TROUGHING OVER THE WESTERN
TWO THIRDS OF CANADA SOUTHWARD INTO THE CENTRAL PLAINS...RIDGING
ALONG THE EAST COAST INTO QUEBEC AND HURRICANE SANDY IN THE
NORTHWEST BAHAMAS. THE FORECAST AREA RESIDES IN THE WAKE OF A STRUNG
OUT SHORTWAVE FROM IOWA INTO EASTERN LAKE SUPERIOR...PROVIDING FOR
SUBSIDENCE AND DRYING ALOFT SEEN ON 00Z SOUNDINGS FROM MPX...ABR AND
BIS. THESE SAME SOUNDINGS SHOW A COLD FRONTAL/SUBSIDENCE INVERSION
AROUND 800MB WITH ABOUT A 50-75MB LAYER OF NEAR SATURATION BELOW IT.
THIS SATURATION WAS REFLECTED BY THE LARGE AMOUNT OF STRATUS
ENCOMPASSING THE NORTHERN PLAINS INTO THE UPPER MISSISSIPPI RIVER
VALLEY REGION LAST EVENING. HOWEVER...DURING THE LAST TWO HOURS A
LARGE AREA OF CLEARING HAS DEVELOPED ACROSS THE FORECAST AREA.
850MB TEMPS HAVE DROPPED CONSIDERABLY WITH THE 00Z MPX SOUNDING
REPORTING -7C...COMPARED TO 2C AT 12Z AND 9C 24 HOURS EARLIER. THIS
COLD AIR HAS BEEN RUSHING IN ON A STILL BREEZY NORTHWEST WIND...
CAUSED BY A TIGHT PRESSURE GRADIENT BETWEEN HIGH PRESSURE IN WESTERN
NEBRASKA AND LOW PRESSURE IN HUDSON BAY. THE WIND HAS KEPT
TEMPERATURES FROM TANKING WITH READINGS MAINLY IN THE 30S.
TODAY THROUGH SATURDAY...26.00Z MODEL GUIDANCE IS IN VERY GOOD
AGREEMENT THAT THE UPPER TROUGH AND ITS AXIS THROUGH THE CENTRAL
PLAINS STAYS NEARLY STATIONARY OR JUST SLOWLY SHIFTS EAST. THIS IS
MOSTLY DUE TO THE BLOCKING AHEAD OF IT...PRODUCED BY THE HIGHLY
AMPLIFIED RIDGING BUILDING UP THROUGH THE CANADIAN MARITIMES AND
HURRICANE SANDY PARALLELING THE SOUTHEAST U.S. COASTLINE. WITH
LITTLE MOVEMENT IN THE UPPER TROUGH...IT WILL BE VERY TOUGH TO GET
ANY PRECIPITATION PRODUCTION...OR WARM ADVECTION FOR THAT MATTER.
HOWEVER...THE HIGH PRESSURE AREA IN NEBRASKA IS PROGGED TO SHIFT
NORTHEAST INTO THE FORECAST AREA FOR LATE TONIGHT AND SATURDAY...
WHICH WILL ALLOW WINDS TO GRADUALLY DIMINISH. BIGGEST ISSUE IS SKY
COVER. WITH THE RECENT CLEARING THAT HAS OCCURRED...WENT WITH A MORE
OPTIMISTIC SCENARIO THAN WHAT THE PAST FEW RUNS OF THE RAP HAVE
SUGGESTED. IDEA HERE IS NOW THAT THE COMBINATION OF DIURNAL
HEATING...LINGERING SURFACE MOISTURE AND COOL AIR ALOFT SHOULD ALLOW
FOR SOME STRATOCUMULUS TO REDEVELOP. DIURNAL COOLING TONIGHT AND THE
HIGH PRESSURE AREA BUILDING IN WILL RESULT IN CLEARING SKIES. A GOOD
AMOUNT OF CIRRUS IS PROGGED TO ADVECT IN FROM THE NORTHWEST ON
SATURDAY...AHEAD OF A SHORTWAVE DROPPING INTO THE TROUGH OVER
NEBRASKA. WITH 850MB TEMPS OF -4 TO -8C BOTH TODAY AND
SATURDAY...TEMPERATURES WILL STRUGGLE TO GET MUCH ABOVE THE LOW TO
MID 40S. THE CLEARING SKIES TONIGHT AND THE COOL AIR IN PLACE SHOULD
EASILY ALLOW TEMPERATURES TO FALL INTO THE 20S...WHILE THE TYPICAL
COLD SPOTS COULD EVEN DROP INTO THE UPPER TEENS.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...THE SHORTWAVE MENTIONED ON
SATURDAY DROPPING INTO NEBRASKA WILL BE A NOTABLE FEATURE...
ESPECIALLY FOR BEING ABLE TO PICK UP SANDY AND HELP CURVE IT BACK
TOWARDS THE MID-ATLANTIC/NORTHEAST EARLY NEXT WEEK. FOR US...THE
SHORTWAVE DIGS DOWN INTO THE TENNESSEE VALLEY BY SUNDAY. ANY
PRECIPITATION ASSOCIATED WITH THIS SHORTWAVE LOOKS TO STAY SOUTH AND
WEST OF THE AREA...WHILE THE HIGH PRESSURE AREA REMAINS NEARLY
STATIONARY. THIS HOLDS TRUE RIGHT THROUGH SUNDAY NIGHT. WITH UPPER
TROUGHING AND HIGH PRESSURE STILL IN PLACE...850MB TEMPS ARE GOING
TO STRUGGLE TO CLIMB...WITH MAYBE A 1-2C RISE OFF OF SATURDAY.
THUS...ANTICIPATING SUNDAYS HIGHS TO BE SIMILAR TO SATURDAY...IN
THE LOW TO MID 40S. SOME CIRRUS AND PERHAPS EVEN MID CLOUD COVER ON
SATURDAY NIGHT SHOULD RESULT IN A SLIGHTLY WARMER NIGHT COMPARED TO
TONIGHT. SAME HOLDS TRUE FOR SUNDAY NIGHT WITH YET ANOTHER AREA OF
CIRRUS PROGGED TO DROP IN FROM THE NORTHWEST.
.LONG TERM...MONDAY THROUGH THURSDAY NIGHT
301 AM CDT FRI OCT 26 2012
26.00Z ECMWF/GFS/CANADIAN/UKMET AND GFS ENSEMBLES ARE ALL IN GOOD
AGREEMENT OF SHOWING A BLOCKED UP UPPER LEVEL PATTERN ACROSS NORTH
AMERICA NEXT WEEK. A LOT OF THIS BLOCKING IS DUE TO SUBTROPICAL
RIDGING STUCK OVER NEWFOUNDLAND...ALLOWING HURRICANE SANDY TO
PHASE WITH THE CURRENT UPPER TROUGH OVER THE CENTRAL PLAINS.
ALTHOUGH THERE ARE CERTAINLY PLENTY OF DETAIL DIFFERENCES ABOUT
THE POST-TROPICAL STATE AND TRACK OF HURRICANE SANDY...OUR AREA
STAYS ON THE WEST/SUBSIDENT SIDE OF THE PHASED SYSTEM. THIS SHOULD
MAINTAIN A RIDGE OF HIGH PRESSURE AT THE SURFACE NEAR OR JUST WEST
OF THE AREA...ALONG WITH DRY WEATHER. NOTE THAT THE 26.00Z ECMWF
DOES SHOW A LITTLE MORE WESTWARD TRACK OF POST-TROPICAL SANDY...
WHICH RESULTS IN A BREEZY TUESDAY AND TUESDAY NIGHT PERIOD. THE
MODEL IS EVEN SUGGESTING THE DEFORMATION BAND COULD GET CLOSE TO
CENTRAL WISCONSIN ON WEDNESDAY. THERE ARE HINTS TOWARDS THURSDAY
NIGHT OF UPPER RIDGING BUILDING OVER THE WESTERN U.S. GETTING
PUSHED EAST TOWARDS THE AREA...THOUGH PLENTY OF UNCERTAINTY EXISTS
ON THIS GIVEN THE ISSUES WITH THE EJECTION OF POST-TROPICAL SANDY.
850MB TEMPS WILL SLOWLY WARM THROUGH NEXT WEEK...WITH MOST AREAS
SEEING READINGS OF 0C OR HIGHER BY WEDNESDAY. THUS...ANTICIPATE A
GENERAL WARMING TREND. FOLLOWED A CONSENSUS SOLUTION FOR
TEMPERATURES.
&&
.AVIATION...THROUGH 18Z SATURDAY
1210 PM CDT FRI OCT 26 2012
SATELLITE AND OBSERVATIONS SHOW A LARGE AREA OF STRATOCUMULUS
SPREADING ACROSS THE REGION. CLOUD DECK HAS ALREADY MOVED OVER
BOTH TAF SITES WITH VFR CEILINGS. LOOKING AT THE 26.15Z RAP AND
26.12Z NAM...IT APPEARS THESE CLOUDS WILL BE HERE FOR A WHILE. THE
BUFKIT SOUNDINGS FROM THE NAM SHOW THIS MOISTURE IS UNDERNEATH AN
INVERSION THAT STARTS AROUND 850 MB AND THIS INVERSION IS EXPECTED
TO REMAIN IN PLACE THROUGH 18Z SATURDAY. BASED ON THIS...WILL SHOW
BOTH TAF SITES KEEPING THE VFR CEILING THROUGH THE PERIOD. THE ONE
CHANCE FOR THE CLOUDS TO DISSIPATE OVERNIGHT RESTS WITH AN OPEN
AREA IN THE CLOUDS OVER NORTH DAKOTA. IF THIS AREA CAN START TO
EXPAND DURING THE NIGHT...IT MIGHT BE ABLE TO REACH THE REGION AND
CLEAR THINGS OUT AND THE EVENING SHIFT WILL NEED TO MONITOR THIS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
301 AM CDT FRI OCT 26 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04