Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 10/28/12
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 TAMPA BAY RUSKIN FL
835 PM EDT SAT OCT 27 2012
.UPDATE (REST OF TONIGHT AND SUNDAY)...
00Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A SLOWLY AMPLIFYING UPPER
LEVEL PATTERN ACROSS THE CONUS THIS EVENING...DOMINATED BY LONGWAVE
TROUGHING OVER THE CENTRAL PORTION OF THE CONTINENT. OTHER BIG
FEATURE OF NOTE IS HURRICANE SANDY SPINNING TO THE EAST OF THE SOUTH
CAROLINA COAST. MODEL GUIDANCE SUITE CONTINUES TO PROG THAT THESE 2
FEATURES WILL INTERACT OVER THE NEXT SEVERAL DAYS TO BRING A
SIGNIFICANT STORM TO A WIDE SWATH OF THE MID-ATLANTIC AND NORTHEAST
COAST OF THE CONUS. WHILE THE INCLEMENT IMPACTS OF THIS STORM WILL
BE FAR REMOVED FROM OUR REGION...THE RESULTING DEEP TROUGH OVER THE
EASTERN CONUS IS EXPECTED TO DELIVER A SHOT OF MUCH COOLER AIR TO
THE FL PENINSULA FOR THE EARLY AND MIDDLE PORTION OF NEXT WEEK. AS
IT LOOKS NOW...THIS WILL BE A TRUE "FALL-LIKE" AIRMASS. MIGHT WE SEE
A FEW EARLY MORNING LOW TEMPS IN THE UPPER 30S FROM BROOKSVILLE
NORTHWARD EARLY NEXT WEEK?
BACK TO THE PRESENT...UPPER LEVEL CIRRUS SHIELD ASSOCIATED WITH
OUTFLOW ON THE WESTERN PERIPHERY OF SANDY BACKED INTO THE NORTHERN
HALF OF THE FORECAST AREA TODAY...BUT IS NOW BEGINNING TO MAKE SOME
PROGRESS BACK TO THE NORTHEAST ON WV IMAGERY. A SWATH OF VERY DRY
AIR ALOFT OVER THE EASTERN GULF OF MEXICO IS POISED TO EXPAND OVER
OUR REGION IN ITS WAKE. 00Z KTBW SOUNDING ALREADY SHOWS A FAIRLY DRY
COLUMN THROUGH THE EXTENT OF THE TROPOSPHERE THIS EVENING WITH A PW
VALUE UNDER 1".
AT THE SURFACE...PRESSURE GRADIENT REMAINS TIGHT OVER THE FLORIDA
PENINSULA BETWEEN HURRICANE SANDY TO THE NORTHEAST AND HIGH PRESSURE
WELL OFF TO THE NORTHWEST. BREEZY NW FLOW WILL BE THE RULE OVERNIGHT
WITH THE STRONGEST GUSTS 20-25 MPH ALONG THE IMMEDIATE COAST.
LOOKING FOR A SEASONABLE NIGHT IN TERMS OF TEMPERATURES WITH WARMEST
READINGS ALONG THE SUNCOAST DUE TO THE FLOW OFF THE WATER. DEEP
LAYER SYNOPTIC SUBSIDENCE/Q-VECTOR DIVERGENCE IN THE WAKE OF SANDY
WILL HELP KEEP OUR RAIN CHANCES NEAR ZERO.
FOR SUNDAY...UPPER LEVEL CIRRUS SHIELD SHOULD CONTINUE ITS EXIT TO
THE NORTHEAST. EXPECTING ANOTHER BREEZY DAY...BUT LIKELY NOT QUITE
AS GUSTY AS THE PAST COUPLE OF DAYS. WILL HAVE TO KEEP AN EYE ON A
DECK OF LOW LEVEL STRATOCU OVER THE NORTH-CENTRAL GULF THIS EVENING.
SOME OF THE GUIDANCE SUGGESTS AN EXPANSION OF THIS BKN DECK EASTWARD
TOWARD OUR COASTAL WATERS AND COASTAL ZONES FROM TAMPA BAY SOUTHWARD
DURING THE DAY TOMORROW. NOT GOING TO SEE ANY PRECIPITATION OUT OF
THESE CLOUDS...BUT IT THEY DO MIGRATE ONSHORE...THEN IT MIGHT BE
ENOUGH TO KEEP TEMPS DOWN A FEW DEGREES FROM WHAT IS CURRENTLY
FORECAST. OTHERWISE...THE END OF THE WEEKEND WILL FEATURE FAIR AND
DRY WEATHER WITH SEASONABLE...TO SLIGHTLY BELOW AVERAGE
TEMPERATURES.
&&
.AVIATION...
VFR NEXT 24 HOURS. CONTINUED GUSTY NORTHWEST WINDS THROUGH SUNDAY.
&&
.MARINE...
A TIGHT PRESSURE GRADIENT REMAINS IN PLACE OVER THE EASTERN GULF OF
MEXICO. NORTH TO NORTHWEST WINDS TO ADVISORY LEVELS AND ROUGH SEAS
WILL CONTINUE THROUGH THE WEEKEND AND INTO THE EARLY PORTION OF NEXT
WEEK. WINDS AND SEAS ARE CURRENTLY EXPECTED TO START RELAXING LATER
MONDAY NIGHT INTO TUESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 66 77 53 72 / 0 0 0 0
FMY 67 81 56 74 / 0 0 0 0
GIF 62 81 53 71 / 0 0 0 0
SRQ 66 75 55 73 / 0 0 0 0
BKV 58 77 47 70 / 0 0 0 0
SPG 69 76 59 71 / 0 0 0 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...BEACH HAZARDS STATEMENT THROUGH SUNDAY EVENING FOR
CHARLOTTE-HILLSBOROUGH-LEE-MANATEE-PINELLAS-SARASOTA.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT MONDAY FOR PINELLAS.
GULF WATERS...SMALL CRAFT ADVISORY UNTIL 8 AM EDT MONDAY FOR BONITA
BEACH TO ENGLEWOOD OUT 20 NM-BONITA BEACH TO
ENGLEWOOD OUT 20 TO 60 NM-ENGLEWOOD TO TARPON SPRINGS
OUT 20 NM-ENGLEWOOD TO TARPON SPRINGS OUT 20 TO 60 NM-
TAMPA BAY WATERS-TARPON SPRINGS TO SUWANNEE RIVER OUT
20 NM-TARPON SPRINGS TO SUWANNEE RIVER OUT 20 TO 60
NM.
&&
$$
UPDATE/MARINE...MROCZKA
AVIATION...JILLSON
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1038 PM EDT SAT OCT 27 2012
.SYNOPSIS...
TROPICAL SYSTEM SANDY CONTINUES TO MOVE NORTH OFFSHORE TONIGHT
AND SUNDAY. THE PRESSURE GRADIENT ASSOCIATED WITH THE SYSTEM WILL
RESULT IN BREEZY CONDITIONS IN THE FORECAST AREA. MOST OF THE RAIN
ASSOCIATED WITH SANDY WILL REMAIN NEAR THE COAST. AN APPROACHING
COLD FRONT WILL MOVE THROUGH THE AREA SUNDAY. THE COLDEST AIR OF
THE SEASON SO FAR WILL FOLLOW THIS FRONT.
&&
.NEAR TERM /OVERNIGHT/...
CURRENT FORECAST REMAINS ON TRACK. REGIONAL RADARS CONTINUE TO
SHOW THE PRECIP ASSOCIATED WITH SANDY REMAINING GENERALLY RIGHT
ALONG THE COAST...THEN EXTENDING OFFSHORE. THE SHOWERS WILL REMAIN WELL
TO THE EAST. BIGGEST ISSUE TONIGHT WILL REVOLVE AROUND THE WINDS.
SURFACE OBSERVATIONS FROM AREA SITES STILL SHOWING WINDS 5 TO 10
MPH ACROSS THE WEST...AND 10-15 MPH WITH GUSTS TO 25 MPH ACROSS
THE EAST. HAVE ADJUSTED WINDS TO BETTER ACCOUNT FOR CURRENT
CONDITIONS...AND TWEAKED WINDS FOR THE OVERNIGHT PERIOD. A LAKE
WIND ADVISORY REMAINS IN EFFECT THROUGH THE NIGHT. MOS LOW
TEMPERATURE GUIDANCE WITH LOWS IN THE LOWER 50S STILL OK.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
THE NAM AND GFS CONTINUE TO SHOW DEEP MOISTURE REMAINING
NORTHEAST OF THE FORECAST AREA AS SANDY MOVES NORTH-NORTHEASTWARD.
THE COLD FRONT SUNDAY STILL APPEARS DRY BECAUSE OF A LACK OF
SIGNIFICANT CONVERGENCE. THE PRESSURE GRADIENT WILL CONTINUE TO
SUPPORT BREEZY CONDITIONS AND WE HAVE MAINTAINED THE LAKE WIND
ADVISORY INTO SUNDAY NIGHT. MODEL GUIDANCE CONSENSUS STILL LOOKED
GOOD FOR THE TEMPERATURE FORECAST.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
STRONG LOW PRESSURE IN THE MIDDLE ATLANTIC AND NORTHEAST STATES
AND RIDGING IN THE MIDDLE OF THE NATION WILL MAINTAIN NORTHWEST
FLOW INTO THE FORECAST AREA DURING THE EXTENDED PERIOD. IT WILL BE
A DRY AND COOL PERIOD. MOSTLY CLEAR SKIES EXCEPT FOR TUESDAY AS
MODELS BRING A DECENT SHORT WAVE AND CLOUDS TO THE REGION. DECIDED
TO USE A MODEL BLEND WITH HIGHS ONLY IN THE LOWER 50S FOR TUESDAY.
OTHERWISE...THE GFS ENSEMBLE MEANS SUPPORT LOWS IN THE 30S.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
VFR EXPECTED THROUGH THE 24 HOUR TAF PERIOD WITH BREEZY CONDITIONS.
THE CENTER OF HURRICANE SANDY IS OVER THE OFFSHORE ATLANTIC WATERS
ABOUT 400 MILES SE OF CAE...PROVIDING OUR FA WITH BREEZY N WINDS AND
A BLANKET OF HIGH LEVEL CLOUDINESS. ASSOCIATED RAIN AREAS ARE ALONG
THE COAST. SLOW MOVING COLD FRONT STILL TO OUR W. SANDY IS FORECAST
TO CONTINUE MOVING TO THE NE...WITH ASSOCIATED RAIN REMAINING EAST
OF THE TERMINALS. LOWER MVFR CIGS ARE CURRENTLY ALONG THE NORTH
COAST...PEE DEE...AND E NC. AS SANDY TRACKS TO THE NE...MODEL
PROJECT LOW LEVEL FLOW OVER OUR FA TO BACK SLIGHTLY TO NNW. THIS
WILL WORK TO KEEP LOWER MVFR CIGS JUST EAST OF THE TERMINALS...PER
LATEST RAP GUIDANCE.
EXTENDED AVIATION OUTLOOK...BREEZY CONDITIONS MAY CONTINUE THROUGH
WEDNESDAY...OTHERWISE NO MAJOR RESTRICTIONS FOR AVIATION INTERESTS
EXPECTED.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...LAKE WIND ADVISORY UNTIL 10 PM EDT SUNDAY FOR SCZ015-016-018-
020>022-025>031-035>038-041.
GA...LAKE WIND ADVISORY UNTIL 10 PM EDT SUNDAY FOR GAZ040-063>065-
077.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
803 PM EDT SAT OCT 27 2012
.SYNOPSIS...
TROPICAL SYSTEM SANDY CONTINUES TO MOVE NORTH OFFSHORE TONIGHT
AND SUNDAY. THE PRESSURE GRADIENT ASSOCIATED WITH THE SYSTEM WILL
RESULT IN BREEZY CONDITIONS IN THE FORECAST AREA. MOST OF THE RAIN
ASSOCIATED WITH SANDY WILL REMAIN NEAR THE COAST. AN APPROACHING
COLD FRONT WILL MOVE THROUGH THE AREA SUNDAY. THE COLDEST AIR OF
THE SEASON SO FAR WILL FOLLOW THIS FRONT.
&&
.NEAR TERM /OVERNIGHT/...
CURRENT FORECAST REMAINS ON TRACK. REGIONAL RADARS CONTINUE TO
SHOW THE PRECIP ASSOCIATED WITH SANDY REMAINING GENERALLY RIGHT
ALONG THE COAST...THEN EXTENDING OFFSHORE. THE SHOWERS ARE
FORECAST TO REMAIN WELL TO THE EAST...SO HAVE GONE WITH A DRY
FORECAST OVERNIGHT FOR ALL AREAS. BIGGEST ISSUE TONIGHT WILL
REVOLVE AROUND THE WINDS. SURFACE OBSERVATIONS FROM AREA SITES
STILL SHOWING WINDS 10 TO 15 MPH ACROSS THE WEST...AND 15-20 MPH
WITH GUSTS TO 30 MPH ACROSS THE EAST. WOULD EXPECT THIS WIND FIELD
TO DOMINATE ALL NIGHT. HAVE ADJUSTED WINDS TO BETTER ACCOUNT FOR
CURRENT CONDITIONS...AND TWEAKED WINDS FOR THE OVERNIGHT PERIOD.
DUE TO THE STRONG WINDS...THE LAKE WIND ADVISORY REMAINS IN EFFECT
THROUGH THE NIGHT. MOS LOW TEMPERATURE GUIDANCE WITH LOWS IN THE
LOWER 50S STILL OK.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
THE NAM AND GFS CONTINUE TO SHOW DEEP MOISTURE REMAINING
NORTHEAST OF THE FORECAST AREA AS SANDY MOVES NORTH-NORTHEASTWARD.
THE COLD FRONT SUNDAY STILL APPEARS DRY BECAUSE OF A LACK OF
SIGNIFICANT CONVERGENCE. THE PRESSURE GRADIENT WILL CONTINUE TO
SUPPORT BREEZY CONDITIONS AND WE HAVE MAINTAINED THE LAKE WIND
ADVISORY INTO SUNDAY NIGHT. MODEL GUIDANCE CONSENSUS STILL LOOKED
GOOD FOR THE TEMPERATURE FORECAST.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
STRONG LOW PRESSURE IN THE MIDDLE ATLANTIC AND NORTHEAST STATES
AND RIDGING IN THE MIDDLE OF THE NATION WILL MAINTAIN NORTHWEST
FLOW INTO THE FORECAST AREA DURING THE EXTENDED PERIOD. IT WILL BE
A DRY AND COOL PERIOD. MOSTLY CLEAR SKIES EXCEPT FOR TUESDAY AS
MODELS BRING A DECENT SHORT WAVE AND CLOUDS TO THE REGION. DECIDED
TO USE A MODEL BLEND WITH HIGHS ONLY IN THE LOWER 50S FOR TUESDAY.
OTHERWISE...THE GFS ENSEMBLE MEANS SUPPORT LOWS IN THE 30S.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
VFR EXPECTED THROUGH THE 24 HOUR TAF PERIOD WITH BREEZY CONDITIONS.
THE CENTER OF HURRICANE SANDY IS OVER THE OFFSHORE ATLANTIC WATERS
ABOUT 400 MILES SE OF CAE...PROVIDING OUR FA WITH BREEZY N WINDS AND
A BLANKET OF HIGH LEVEL CLOUDINESS. ASSOCIATED RAIN AREAS ARE ALONG
THE COAST. SLOW MOVING COLD FRONT STILL TO OUR W. SANDY IS FORECAST
TO CONTINUE MOVING TO THE NE...WITH ASSOCIATED RAIN REMAINING EAST
OF THE TERMINALS. LOWER MVFR CIGS ARE CURRENTLY ALONG THE NORTH
COAST...PEE DEE...AND E NC. AS SANDY TRACKS TO THE NE...MODEL
PROJECT LOW LEVEL FLOW OVER OUR FA TO BACK SLIGHTLY TO NNW. THIS
WILL WORK TO KEEP LOWER MVFR CIGS JUST EAST OF THE TERMINALS...PER
LATEST RAP GUIDANCE.
EXTENDED AVIATION OUTLOOK...BREEZY CONDITIONS MAY CONTINUE THROUGH
WEDNESDAY...OTHERWISE NO MAJOR RESTRICTIONS FOR AVIATION INTERESTS
EXPECTED.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...LAKE WIND ADVISORY UNTIL 10 PM EDT SUNDAY FOR SCZ015-016-018-
020>022-025>031-035>038-041.
GA...LAKE WIND ADVISORY UNTIL 10 PM EDT SUNDAY FOR GAZ040-063>065-
077.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
720 PM EDT SAT OCT 27 2012
.SYNOPSIS...
TROPICAL SYSTEM SANDY CONTINUES TO MOVE NORTH OFFSHORE TONIGHT
AND SUNDAY. THE PRESSURE GRADIENT ASSOCIATED WITH THE SYSTEM WILL
RESULT IN BREEZY CONDITIONS IN THE FORECAST AREA. MOST OF THE RAIN
ASSOCIATED WITH SANDY WILL REMAIN NEAR THE COAST. AN APPROACHING
COLD FRONT WILL MOVE THROUGH THE AREA SUNDAY. THE COLDEST AIR OF
THE SEASON SO FAR WILL FOLLOW THIS FRONT.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
REGIONAL RADARS CONTINUE TO SHOW THE PRECIP ASSOCIATED WITH
SANDY REMAINING GENERALLY RIGHT ALONG THE COAST...THEN EXTENDING
OFFSHORE. THE SHOWERS ARE FORECAST TO REMAIN WELL TO THE EAST...SO
HAVE GONE WITH A DRY FORECAST OVERNIGHT FOR ALL AREAS. BIGGEST
ISSUE TONIGHT WILL REVOLVE AROUND THE WINDS. SURFACE OBSERVATIONS
FROM AREA SITES STILL SHOWING WINDS 10 TO 15 MPH ACROSS THE
WEST...AND 15-20 MPH WITH GUSTS TO 30 MPH ACROSS THE EAST. WOULD
EXPECT THIS WIND FIELD TO DOMINATE ALL NIGHT. HAVE ADJUSTED WINDS
TO BETTER ACCOUNT FOR CURRENT CONDITIONS...AND TWEAKED WINDS FOR
THE OVERNIGHT PERIOD. DUE TO THE STRONG WINDS...THE LAKE WIND
ADVISORY REMAINS IN EFFECT THROUGH THE NIGHT. MOS LOW TEMPERATURE
GUIDANCE WITH LOWS IN THE LOWER 50S STILL OK.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
THE NAM AND GFS CONTINUE TO SHOW DEEP MOISTURE REMAINING
NORTHEAST OF THE FORECAST AREA AS SANDY MOVES NORTH-NORTHEASTWARD.
THE COLD FRONT SUNDAY STILL APPEARS DRY BECAUSE OF A LACK OF
SIGNIFICANT CONVERGENCE. THE PRESSURE GRADIENT WILL CONTINUE TO
SUPPORT BREEZY CONDITIONS AND WE HAVE MAINTAINED THE LAKE WIND
ADVISORY INTO SUNDAY NIGHT. MODEL GUIDANCE CONSENSUS STILL LOOKED
GOOD FOR THE TEMPERATURE FORECAST.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
STRONG LOW PRESSURE IN THE MIDDLE ATLANTIC AND NORTHEAST STATES
AND RIDGING IN THE MIDDLE OF THE NATION WILL MAINTAIN NORTHWEST
FLOW INTO THE FORECAST AREA DURING THE EXTENDED PERIOD. IT WILL BE
A DRY AND COOL PERIOD. MOSTLY CLEAR SKIES EXCEPT FOR TUESDAY AS
MODELS BRING A DECENT SHORT WAVE AND CLOUDS TO THE REGION. DECIDED
TO USE A MODEL BLEND WITH HIGHS ONLY IN THE LOWER 50S FOR TUESDAY.
OTHERWISE...THE GFS ENSEMBLE MEANS SUPPORT LOWS IN THE 30S.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
VFR EXPECTED THROUGH THE 24 HOUR TAF PERIOD WITH BREEZY CONDITIONS.
THE CENTER OF HURRICANE SANDY IS OVER THE OFFSHORE ATLANTIC WATERS
ABOUT 400 MILES SE OF CAE...PROVIDING OUR FA WITH BREEZY N WINDS AND
A BLANKET OF HIGH LEVEL CLOUDINESS. ASSOCIATED RAIN AREAS ARE ALONG
THE COAST. SLOW MOVING COLD FRONT STILL TO OUR W. SANDY IS FORECAST
TO CONTINUE MOVING TO THE NE...WITH ASSOCIATED RAIN REMAINING EAST
OF THE TERMINALS. LOWER MVFR CIGS ARE CURRENTLY ALONG THE NORTH
COAST...PEE DEE...AND E NC. AS SANDY TRACKS TO THE NE...MODEL
PROJECT LOW LEVEL FLOW OVER OUR FA TO BACK SLIGHTLY TO NNW. THIS
WILL WORK TO KEEP LOWER MVFR CIGS JUST EAST OF THE TERMINALS...PER
LATEST RAP GUIDANCE.
EXTENDED AVIATION OUTLOOK...BREEZY CONDITIONS MAY CONTINUE THROUGH
WEDNESDAY...OTHERWISE NO MAJOR RESTRICTIONS FOR AVIATION INTERESTS
EXPECTED.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...LAKE WIND ADVISORY UNTIL 10 PM EDT SUNDAY FOR SCZ015-016-018-
020>022-025>031-035>038-041.
GA...LAKE WIND ADVISORY UNTIL 10 PM EDT SUNDAY FOR GAZ040-063>065-
077.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
659 PM CDT SAT OCT 27 2012
.DISCUSSION...
330 PM CDT
MAIN FORECAST CONCERNS/CHALLENGES ARE WITH PERSISTENT LAKE EFFECT
CLOUD COVER AND LIGHT SHOWERS WITH COOL DRY CONDITIONS EXPECTED
FOR THE REMAINDER OF THE CWA...WITH EVENTUALLY OUR WEATHER TO BE
DICTATED BY LARGE SCALE PATTERN OWING TO SANDY.
WITH THE LAKE EFFECT CLOUD COVER AND ISOLATED LIGHT SHOWERS
AFFECTING AREAS NEAR THE LAKE IN NORTHWEST INDIANA AND EVENTUALLY
NORTHEAST ILLINOIS TONIGHT...HAVE MADE ONLY MINOR TWEAKS TO THE
POP/WX THROUGH THE REMAINDER OF THE WEEKEND. LATEST SATELLITE
IMAGERY STILL DEPICTING AXIS OF CONVERGENCE ALONG THE EASTERN SIDE
OF THE LAKE AS WELL AS WITH BOTH SURFACE OBS AND RAP ANALYSIS
PAINTING A SIMILAR PICTURE. ALTHOUGH...THIS AXIS OF CONVERGENCE
HAS WEAKENED SOMEWHAT EARLY THIS AFTERNOON WITH THE LOSS OF
SYNOPTIC AND LAND BREEZE INTERACTION...WITH DIURNAL TRENDS AIDING
FOR MORE SYNOPTIC NORTH TO NORTHWEST FLOW ALONG THE EASTERN
PORTIONS OF THE LAKE. NONETHELESS...WITH SUFFICIENT DELTA TS AND
WEAK CONVERGENCE...CLOUD COVER CONTINUES TO DEVELOP AND SPILL
INLAND THIS AFTERNOON. HAD MAINTAINED ISOLATED LIGHT SHOWERS FOR
AREAS ACROSS THE SOUTHEAST PORTION OF THE LAKE AND PORTER COUNTY
WHERE BETTER CONVERGENCE RESIDED...BUT HAVE NOT SEEN MUCH
DEVELOPMENT IF ANY AT ALL THIS AFTERNOON. ALTHOUGH...COULD NOT
RULE OUT SOME SPRINKLES OR LIGHT SHOWERS TO DEVELOP UNDER THIS
BEST AXIS OF CONVERGENCE THROUGH THE REMAINDER OF THE AFTERNOON.
CURRENT SHORT WAVE TROUGH OVER THE ROCKIES/PLAINS WILL QUICKLY
WORK ITS WAY EAST/SOUTHEAST...AS THE LARGE UPPER LEVEL TROUGH DIGS
SOUTH ACROSS THE REGION TONIGHT. AS THIS OCCURS...LOW LEVEL FLOW
WILL RESPOND AND SHIFT MORE NORTHERLY/NORTHEASTERLY. THIS SHIFT IN
FLOW WILL BRING THIS CONVERGENT AXIS WEST ORIENTING ITSELF SUCH
THAT I EXPECT CURRENT CLOUD COVER TO BEGIN SPILLING ONTO NORTHEAST
ILLINOIS. THE PRESENCE OF SIMILAR DELTA TS WITH ONCE
AGAIN...INCREASING LOW LEVEL CONVERGENCE TONIGHT...EXPECT LAKE
EFFECT CLOUD COVER TO PERSIST WITH SLIGHTLY BETTER CHANCES FOR
SOME ISOLATED LIGHT SHOWERS. A LONGER FETCH EXTENDING FROM THE FAR
NORTHERN PORTIONS OF THE LAKE SHOULD AID IN A BETTER ENVIRONMENT
FOR THIS LIGHT PRECIP TO DEVELOP. HIRES DATA DOES SUPPORT THIS
SCENARIO WITH GUIDANCE SHOWING A NARROW AXIS DEVELOPING FROM MID
LAKE AND THEN EXTENDING SOUTHWEST INTO FAR NORTHEAST ILLINOIS AND
FAR NORTHWEST INDIANA. WITH PREVIOUSLY MENTIONED CONDITIONS IN
PLACE...CANNOT REALLY ARGUE THIS POSSIBILITY. ALTHOUGH...I WONDER
HOW MUCH MOISTURE WILL BE AVAILABLE FOR THIS WEAK FORCING TO WORK
WITH. THIS WILL OF COURSE PLAY A BIG PART WITH OVERALL
DEVELOPMENT...BUT MORE IMPORTANTLY COVERAGE. HAVE TRIED TO ADD
SOME ADDED DETAIL TO THE POP/WX GRID TRYING TO SHOW A MORE NARROW
AXIS OF DEVELOPMENT....KEEPING ISOLATED LIGHT SHOWERS TONIGHT AS
WELL AS FOR MOST OF SUNDAY. ALTHOUGH THIS LIGHT PRECIP WILL BE
SOMEWHAT IN QUESTION...CLOUD COVER WILL NOT AND SHOULD SPAN MOST
OF NORTHEAST ILLINOIS AND NORTHWEST INDIANA LATE TONIGHT INTO
SUNDAY. EXPECT BOUNDARY LAYER FLOW THEN TO SHIFT MORE NORTHERLY
SUNDAY NIGHT INTO MONDAY WITH THIS CLOUD COVER AND ISOLATED
SHOWERS TO SHIFT BACK PRIMARILY INTO NORTHWEST INDIANA. MOISTURE
WILL THEN BE LACKING GOING INTO MONDAY...WITH PRECIP REALLY NOT
BECOMING LIKELY.
DRY CONDITIONS WILL TAKE PLACE FOR THE ENTIRE CWA MONDAY NIGHT
AND THROUGH MOST OF TUESDAY...AS SIGNIFICANT LARGE SCALE
INTERACTION WILL TAKE PLACE ACROSS THE EAST COAST. THIS CURRENT
LARGE SCALE TROUGH OVERHEAD WILL EVENTUALLY INTERACT WITH SANDY
OVER THE EAST COAST DURING THE START OF NEXT WEEK. WHAT THIS WILL
MEAN FOR AREAS IN OUR LOCATION...IS A LARGE STRONG UPPER LEVEL
SYSTEM THAT WILL SPAN MUCH OF THE EASTERN HALF OF THE US. MOISTURE
WRAPPING AROUND THIS SYSTEM WILL THEN WORK ITS WAY NEAR THE CWA
BUT PRIMARILY OVER THE EASTERN PORTION OF LAKE MICHIGAN THROUGH
MID WEEK. ALTHOUGH THERE IS STILL SOME UNCERTAINTY AS TO THE
OVERALL EVOLUTION WITH THIS LARGE SYSTEM AS WELL AS
MOISTURE/PRECIP REACHING THE CWA...IT DOES APPEAR AS THE BEST AXIS
OF PRECIP SHOULD STAY EAST. WHAT IS NOT IN QUESTION MONDAY THROUGH
WEDNESDAY IS THE STRONG NORTHERLY FLOW THAT WILL TAKE PLACE OVER
THE CWA AND MORE IMPORTANTLY OVER THE LAKE. THIS STRONG FLOW WILL
BRING LARGE WAVES CRASHING SOUTH OVER THE SOUTHERN END OF THE LAKE
AND ONTO AREAS NEAR THE LAKE...WITH HIGH WAVES ON BOTH THE
ILLINOIS AND INDIANA NEARSHORE WATERS EXPECTED BUT WITH THE
HIGHEST WAVES EXPECTED OVER INDIANA. WILL CONTINUE TO WATCH THIS
SITUATION CLOSELY AS HIGH WINDS AND EVEN SOME LAKE SHORE FLOODING
COULD EVENTUALLY BE ISSUES FOR AREAS IMMEDIATELY NEAR THE LAKE.
RODRIGUEZ
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* POTENTIAL FOR MVFR CEILING DEVELOPMENT 2500-3000 FT LATER
TONIGHT INTO SUNDAY MORNING.
* SPOTTY LAKE-EFFECT SHOWERS POSSIBLE MAINLY EARLY SUNDAY.
* NORTH-NORTHEAST WINDS WITH GUSTS AROUND 15 KT AGAIN SUNDAY.
RATZER
//DISCUSSION...UPDATED 00Z...
THE MAIN SURFACE WEATHER FEATURE REMAINS AN AREA OF HIGH PRESSURE
LIFTING NORTHEAST FROM IA INTO WI THIS EVENING...WITH NORTH-
NORTHEAST WINDS AROUND THE SOUTHEASTERN PERIPHERY OF THE SURFACE
HIGH. DEVELOPMENT OF NOCTURNAL INVERSION AFTER SUNSET HAS ALLOWED
GUSTS TO DIMINISH...AND CHICAGO AREA TERMINALS DPA/ORD/MDW SHOULD
SEE WINDS BACK TO 340-350 DEG AS WEAK LAND BREEZE DEVELOPS BY LATE
EVENING. GYY...FARTHER TO THE SOUTHEAST AND MUCH CLOSER TO THE
LAKE...WILL SEE SOMEWHAT GUSTY NORTH-NORTHEAST WINDS CONTINUE
THROUGH THE NIGHT.
COOLER AIR ON NORTH-NORTHEAST WINDS ALOFT HAD RESULTED IN SOME
FLAT MVFR-VFR STRATOCU ACROSS THE LAKE EARLIER TODAY...WHICH
AFFECTED GYY FOR A TIME. WINDS ALOFT ARE EXPECTED TO SHIFT A BIT
MORE NORTHEASTERLY TONIGHT/SUNDAY...WHICH SHOULD ALLOW FAVORABLE
CONVERGENT AXIS TO SHIFT WEST AND MOVE LAKE-INDUCED CLOUDS INTO
SOME OF THE CHICAGO AREA TERMINALS LATE THIS EVENING INTO SUNDAY.
THUS BKN-OVC CEILINGS ARE EXPECTED TO DEVELOP DURING THE LATE
EVENING AND OVERNIGHT HOURS...WITH CIGS LIKELY IN THE MVFR RANGE
CLOSER TO THE LAKE SHORE. THIS IS EXPECTED TO CONTINUE INTO SUNDAY
WITH NORTHEAST WINDS AGAIN BECOMING SOMEWHAT GUSTY AGAIN. VARIOUS
MODELS DO INDICATE SOME RAISING OF CIGS THROUGH THE AFTERNOON
HOURS...WITH CONDITIONS IMPROVING TO VFR LATER IN THE DAY.
SOME SCATTERED LAKE-EFFECT RAIN SHOWERS WILL BE POSSIBLE LATE
TONIGHT THROUGH MIDDAY SUNDAY AS WELL...AS THE DEPTH OF
MOIST/UNSTABLE AIR OVER THE WATER INCREASES. TIMING/PLACEMENT OF
THESE SHOWERS WITH RESPECT TO INDIVIDUAL POINT LOCATIONS REMAINS A A
BIT SUSPECT AT THIS TIME AND HAVE HELD TAFS DRY FOR NOW...BUT MAY
HAVE TO HAD VCSH OR A TEMPO SHRA MENTION IN LATER UPDATES IF
SHOWERS INDEED FORM.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* MEDIUM CONFIDENCE IN CEILING TRENDS AND MVFR CONDITIONS
DEVELOPING TONIGHT/EARLY SUNDAY.
* HIGH CONFIDENCE IN WIND TRENDS.
RATZER
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...GENERALLY VFR. SMALL THREAT OF LOCALIZED LAKE EFFECT
MVFR CIGS AND SLIGHT CHANCE OF SHRA.
TUESDAY THROUGH THURSDAY...GENERALLY VFR. LOW PROBABILITY OF
LOCALIZED SHOWERS WITH GUSTY NNW WINDS TUES-WED.
RATZER
&&
.MARINE...
423 PM CDT
HIGH PRESSURE HAS MOVED OVER THE NORTHERN MISSISSIPPI RIVER VALLEY
THIS AFTERNOON AND THE AXIS OF THE SURFACE RIDGE WILL REMAIN
CENTERED JUST WEST OF LAKE MICHIGAN THROUGH MID NEXT WEEK. NORTH
WINDS ARE ALSO EXPECTED THROUGH MID NEXT WEEK. AS SUCH...CONTINUED
THE SMALL CRAFT ADVISORY FOR HIGH WAVES. WINDS WILL ALSO PICK UP
TO 20 TO 25 KT TONIGHT.
THE REMNANTS OF HURRICANE SANDY MOVE ASHORE LATE MONDAY INTO MONDAY
NIGHT AND GUIDANCE DIFFERS ON HOW FAR WEST THE TIGHTENED PRESSURE
GRADIENT WILL EXTEND. GALES WILL DEVELOP ACROSS THE LAKE LATE
MONDAY AFTERNOON...AND HAVE ISSUED A GALE WATCH FOR THE OPEN WATERS.
GALES ARE ALSO LIKELY ALONG THE NEARSHORE ZONES...DEVELOPING FIRST
SOUTH AND EAST OF NORTHERLY ISLAND...THEN SPREADING INTO THE
NORTHERN INDIANA NEARSHORE WATERS.
WINDS WILL PROBABLY INCREASE TO STORM FORCE GUSTS TO 50 KT FOR A
TIME ON TUESDAY ACROSS THE LAKE AND NEARSHORE WATERS SOUTH AND EAST
OF NORTHERLY ISLAND. WHILE CONFIDENCE IS HIGH THAT THERE WILL BE AN
EXTENDED PERIOD OF GALES...ONLY HAVE MODERATE CONFIDENCE IN STORM
FORCE GUSTS. MULTIPLE GUIDANCE MEMBERS INDICATE THE PRESSURE
GRADIENT WILL TIGHTEN TUESDAY AND SUSTAINED GUSTS UP TO 50 KT ARE
POSSIBLE...BUT WANT TO SEE IF NEXT SET OF MODEL RUNS REMAIN
CONSISTENT. THEREFORE WILL HOLD OFF ON ISSUING A STORM FORCE
WATCH NOW.
IT CURRENTLY LOOKS LIKE WINDS WILL DIMINISH TO BELOW GALES LATE
WEDNESDAY EVENING/EARLY WEDNESDAY NIGHT. WINDS WILL SLOWLY BECOME
MORE NORTHWEST AND DIMINISH AS THE LOW OVER THE EAST COAST WEAKENS
AND LIFTS TO THE NORTHEAST. RELIEF FROM THE PERSISTENT NORTH WINDS
LOOKS LIKE IT MAY ARRIVE NEXT SATURDAY.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE NORTHERLY IS TO MICHIGAN CITY IN UNTIL 1 PM
MONDAY.
GALE WATCH...LMZ742-LMZ743-LMZ744-LMZ745...1 PM MONDAY TO 4 PM
WEDNESDAY.
SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO NORTHERLY IS UNTIL 10 PM MONDAY.
GALE WATCH...LMZ740-LMZ741...10 PM MONDAY TO 10 PM TUESDAY.
GALE WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...1 PM MONDAY TO 9 PM
WEDNESDAY.
&&
$$
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 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 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.
&&
$$
UPDATE...DLF
SHORT TERM...DR
LONG TERM...JTL
AVIATION...DLF
AREA FORECAST DISCUSSION
NWS TOPEKA KS
639 AM CDT FRI OCT 26 2012
...UPDATE TO AVIATION...
.DISCUSSION...
SHORTWAVE TROUGH WAS LOCATED OVER COLORADO AND THE NEBRASKA
PANHANDLE WITHIN A BROADER TROUGH MOVING INTO THE CENTRAL STATES.
COLD HIGH PRESSURE WAS CENTERED OVER NORTH CENTRAL NEBRASKA THIS
MORNING. LOW CLOUD DECK WAS DISSIPATING OVER NORTHEAST KANSAS WITH
MOST AREAS NORTH OF INTERSTATE 70 CLEAR. OUT WEST HIGH AND MID
LEVEL CLOUDS WERE SPILLING INTO NORTH CENTRAL KANSAS AS WELL.
TEMPERATURES WILL START OFF NEAR FREEZING THEN WARM ONLY INTO THE
MID AND UPPER 40S TODAY.
TONIGHT SKIES WILL CLEAR OUT AS THE SHORTWAVE TROUGH EXITS THE AREA
AND HIGH PRESSURE RIDGE SETTLES OVER THE NORTHEAST KANSAS. WITH THE
LIGHT WINDS AND CLEAR SKIES EXPECT GOOD RADIATIONAL COOLING WITH
TEMPS FALLING INTO THE LOW TO MID 20S.
THE COLD TEMPERATURES WILL CONTINUE THROUGH SUNDAY WITH NORTHWEST
FLOW ALOFT AND THE SURFACE HIGH PRESSURE RIDGE REMAINING IN THE
AREA. LOWS IN THE MID AND UPPER 20S SUNDAY MORNING WITH HIGHS IN THE
LOWER 50S.
FOR MONDAY THROUGH THURSDAY...A GRADUAL WARM UP IS EXPECTED AS
HEIGHTS RISE OVER THE CENTRAL PLAINS AND ROCKIES. TEMPERATURES WILL
RANGE FROM THE MID AND UPPER 50S FOR MONDAYS HIGHS TO THE UPPER 50S
TO LOWER 60S TUESDAY THROUGH THURSDAY. LOWS WILL RANGE FROM THE 30S
MONDAY TO THE UPPER 30S TO LOWER 40S FOR THE REST OF THE PERIOD.
53
&&
.AVIATION...
VFR CONDITIONS EXPECTED. STRATUS JUST ABOVE MVFR LINGERS IN THE
TOP/FOE AREA THIS MORNING AND MODELS HAVE BEEN STRUGGLING TO KEEP
UP WITH THE STRATUS OVERNIGHT. LATEST RAP AND HRRR RUNS...WHICH
HAVE BEEN DOING THE BEST...KEEP LIMITING CLOUDS OUT AND WILL
CAUTIOUSLY GO THIS ROUTE.
65
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
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 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
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 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 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...UPDATED
NWS PITTSBURGH PA
930 PM EDT SAT OCT 27 2012
.SYNOPSIS...
A STALLED COLD FRONT NEAR THE MOUNTAINS...COMBINED WITH NORTHBOUND
HURRICANE SANDY...WILL PROVIDE PERIODS OF CHILLY RAIN DURING THE
UPCOMING DAYS. FOR MONDAY INTO TUESDAY...RAIN MAY BECOME HEAVY
MAKING FLOODING A POSSIBILITY...PLUS IT CAN BE WINDY. THERE MAY
EVEN BE SOME SNOWFALL...WITH POSSIBLE ACCUMULATION ON THE RIDGES.
&&
.NEAR TERM /THROUGH SUNDAY/...
LINE OF SHOWERS CONTINUES TO DISSIPATE AS THE MID-LEVEL MOISTURE
MOVES EASTWARD. EXPECT SHOWERS TO REDEVELOP LATE TONIGHT AS THE
MID-LEVEL MOISTURE SWINGS BACK TO THE WEST AND A WEAK SHORTWAVE
MOVES THROUGH. MINOR ADJUSTMENTS TO OVERNIGHT TEMPS.
PREVIOUS DISCUSSION...
PER RECENT HRRR AND WRF-NAM MODEL OUTPUT...EXPECT BAND OF LIGHT
RAIN TO MEANDER ACROSS THE UPPER OHIO VALLEY THIS PERIOD. THE RAIN
BAND IS ASSOCIATED WITH STALLED COLD FRONT NEAR THE APPALACHIAN
MOUNTAINS.
FORECASTED TEMPERATURES TO REMAIN MAINLY IN THE 40S PER BLEND OF
RECENT GFS AND NAM MOS.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
PER BLEND OF RECENT MODEL OUTPUT...SREF ECMWF CMC AND GFS...EXPECT
HURRICANE SANDY TO TURN NORTHWESTWARD TOWARD PENNSYLVANIA
MONDAY...WITH THE COLD FRONT STILL STALLED ACROSS THE APPALACHIAN
MOUNTAINS. INTERACTION BETWEEN THE SYSTEMS WILL FURTHER INCREASE
THE JET STREAM ALOFT...AND CAN CAUSE STRONG FRONTOGENETICAL LIFT.
HENCE FORESEE THE POTENTIAL FOR HEAVY RAIN AND STRONG WIND GUSTS
MONDAY INTO TUESDAY. HENCE HAVE ISSUED A FLOOD WATCH AND HIGH WIND
WATCH MONDAY INTO TUESDAY.
SURFACE LAYER COOLING MAY CAUSE COLD ENOUGH TEMPERATURES ACROSS
THE HIGHER WV-MD MOUNTAINS FOR THERE TO BE A PERIOD OF
ACCUMULATING SNOW. ELSEWHERE TEMPERATURES WILL BE MAINLY IN THE
40S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE STRONG LOW RESULTING FROM THE PHASING OF HURRICANE SANDY AND
THE COLD UPPER TROUGH WILL BE SLOW TO EXIT NORTH THIS PERIOD. DUE
TO ALL THE UNCERTAINTY HAVE CONTINUED MENTION OF A CHANCE OF
RAIN SHOWERS INTO FRIDAY WITH SNOW SHOWERS POSSIBLE ACROSS THE
HIGHER WV-MD MOUNTAINS.
FORECASTED CONTINUED COLDER THAN NORMAL TEMPERATURES BASED ON
RECENT GFS AND ECMWF MODEL OUTPUT. ONCE THE COLD LOW CENTER
EXITS...DRYING WILL BEGIN AND TEMPERATURES COULD REBOUND TOWARD
NORMAL VALUES NEXT WEEKEND.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
WITH THE SLOW EASTBOUND COLD FRONT HAVING BARELY REACHED THE WESTERN
SLOPES OF THE APPALACHIAN MOUNTAINS...STRATUS CEILINGS TO BE IN
THE IFR RANGE WITH PERIODS OF LIGHT RAIN TONIGHT.
VISIBILITIES WITH THE FRONTAL BAND OF RAIN MAY BECOME MVFR AT TIMES.
SURFACE WINDS WILL BE MAINLY FROM THE NORTH AT 6 TO 12 KTS INTO
TONIGHT.
.OUTLOOK.../SUNDAY THROUGH WEDNESDAY/...
REMNANT MOISTURE FROM SANDY COMBINED WITH A COLD CANADIAN UPPER
TROUGH WILL BRING FREQUENT MVFR TO IFR RESTRICTIONS DUE TO RAIN
THROUGH THIS PERIOD. WITH THE REMNANTS OF HURRICANE SANDY FORECAST
TO PUSH DUE WEST ACROSS SOUTHERN PA MONDAY NIGHT INTO TUESDAY
PERIODS OF STRONG WINDS MONDAY NIGHT AND TUESDAY COULD BE
SUSTAINED NEAR 35 KNOTS WITH GUSTS OF 55 TO 60 KNOTS POSSIBLE
BEFORE THE STORM WEAKENS TUESDAY. PERIODS OF INTENSE RAINFALL
CAN ALSO BE EXPECTED DURING THE MONDAY NIGHT INTO TUESDAY
PERIOD. AS THE STORM WEAKENS AND MOVE NORTH TUESDAY NIGHT
INTO WEDNESDAY. WINDS WILL DIMINISH BUT GUSTS OF 25 TO 35 KNOTS
ARE POSSIBLE EVEN INTO WEDNESDAY AFTERNOON. RAINFALL WILL DIMINISH
RAPIDLY WEDNESDAY.
&&
.HYDROLOGY...
AS MENTIONED ABOVE...RAINFALL TOTALS THROUGH EARLY WEDNESDAY ARE
FORECAST IN THE 2 TO 4.5 INCH RANGE FOR THE MONONGAHELA AND
ALLEGHENY RIVER BASINS. FORECAST MODELS IN THE HANDLING OF THIS
SYSTEMS ACTUAL TRACK. GUIDANCE FROM THE HYDROMETEOROLOGICAL
PREDICTION CENTER HAS GENERALLY THE SAME AREA IN EXCESS OF THREE
INCHES ACROSS THOSE SAME AREAS.
SHOULD EITHER OF THESE TOTAL BE REALIZED ON A WIDESPREAD BASIS...THEN
SMALL STREAM FLOODING WOULD OCCUR BY LATER ON MONDAY AND INTO
TUESDAY...WITH RIVER RISES LATE TUESDAY AND WEDNESDAY...WITH FLOODING
FOLLOWING IF MAXIMUM AMOUNTS ARE REALIZED.
FOR NOW...A MENTION OF SUCH POTENTIAL WILL BE INCLUDED IN THE
HAZARDOUS WEATHER OUTLOOK. ADDITIONAL PRODUCTS WILL FOLLOW DURING
THE NEXT FEW DAYS SHOULD THE SITUATION MATERIALIZE FURTHER.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
MDZ001.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR MDZ001.
OH...FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
OHZ039>041-048>050-057>059-068-069.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR OHZ039>041-048>050-057>059-068-069.
PA...FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
PAZ007>009-013>016-020>023-029-031-073>076.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR PAZ007>009-013>016-020>023-029-031-073>076.
WV...FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
WVZ001>004-012-021>023-041.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR WVZ001>004-012-021>023-041.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
823 PM EDT SAT OCT 27 2012
.SYNOPSIS...
A STALLED COLD FRONT NEAR THE MOUNTAINS...COMBINED WITH NORTHBOUND
HURRICANE SANDY...WILL PROVIDE PERIODS OF CHILLY RAIN DURING THE
UPCOMING DAYS. FOR MONDAY INTO TUESDAY...RAIN MAY BECOME HEAVY
MAKING FLOODING A POSSIBILITY...PLUS IT CAN BE WINDY. THERE MAY
EVEN BE SOME SNOWFALL...WITH POSSIBLE ACCUMULATION ON THE RIDGES.
&&
.NEAR TERM /THROUGH SUNDAY/...
HAVE MADE MINOR CHANGES TO POPS AND TEMPS FOR LATEST UPDATE. THIN
LINE OF SHOWERS HAS NOT MADE AS MUCH EASTWARD PROGRESSION AS
PREVIOUS FORECAST INDICATED...ADDITIONALLY THE SOUTHERN PORTION OF
THE LINE IS DECAYING.
PREVIOUS DISCUSSION...
PER RECENT HRRR AND WRF-NAM MODEL OUTPUT...EXPECT BAND OF LIGHT
RAIN TO MEANDER ACROSS THE UPPER OHIO VALLEY THIS PERIOD. THE RAIN
BAND IS ASSOCIATED WITH STALLED COLD FRONT NEAR THE APPALACHIAN
MOUNTAINS.
FORECASTED TEMPERATURES TO REMAIN MAINLY IN THE 40S PER BLEND OF
RECENT GFS AND NAM MOS.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
PER BLEND OF RECENT MODEL OUTPUT...SREF ECMWF CMC AND GFS...EXPECT
HURRICANE SANDY TO TURN NORTHWESTWARD TOWARD PENNSYLVANIA
MONDAY...WITH THE COLD FRONT STILL STALLED ACROSS THE APPALACHIAN
MOUNTAINS. INTERACTION BETWEEN THE SYSTEMS WILL FURTHER INCREASE
THE JET STREAM ALOFT...AND CAN CAUSE STRONG FRONTOGENETICAL LIFT.
HENCE FORESEE THE POTENTIAL FOR HEAVY RAIN AND STRONG WIND GUSTS
MONDAY INTO TUESDAY. HENCE HAVE ISSUED A FLOOD WATCH AND HIGH WIND
WATCH MONDAY INTO TUESDAY.
SURFACE LAYER COOLING MAY CAUSE COLD ENOUGH TEMPERATURES ACROSS
THE HIGHER WV-MD MOUNTAINS FOR THERE TO BE A PERIOD OF
ACCUMULATING SNOW. ELSEWHERE TEMPERATURES WILL BE MAINLY IN THE
40S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE STRONG LOW RESULTING FROM THE PHASING OF HURRICANE SANDY AND
THE COLD UPPER TROUGH WILL BE SLOW TO EXIT NORTH THIS PERIOD. DUE
TO ALL THE UNCERTAINTY HAVE CONTINUED MENTION OF A CHANCE OF
RAIN SHOWERS INTO FRIDAY WITH SNOW SHOWERS POSSIBLE ACROSS THE
HIGHER WV-MD MOUNTAINS.
FORECASTED CONTINUED COLDER THAN NORMAL TEMPERATURES BASED ON
RECENT GFS AND ECMWF MODEL OUTPUT. ONCE THE COLD LOW CENTER
EXITS...DRYING WILL BEGIN AND TEMPERATURES COULD REBOUND TOWARD
NORMAL VALUES NEXT WEEKEND.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
WITH THE SLOW EASTBOUND COLD FRONT HAVING BARELY REACHED THE WESTERN
SLOPES OF THE APPALACHIAN MOUNTAINS...STRATUS CEILINGS TO BE IN
THE IFR RANGE WITH PERIODS OF LIGHT RAIN TONIGHT.
VISIBILITIES WITH THE FRONTAL BAND OF RAIN MAY BECOME MVFR AT TIMES.
SURFACE WINDS WILL BE MAINLY FROM THE NORTH AT 6 TO 12 KTS INTO
TONIGHT.
.OUTLOOK.../SUNDAY THROUGH WEDNESDAY/...
REMNANT MOISTURE FROM SANDY COMBINED WITH A COLD CANADIAN UPPER
TROUGH WILL BRING FREQUENT MVFR TO IFR RESTRICTIONS DUE TO RAIN
THROUGH THIS PERIOD. WITH THE REMNANTS OF HURRICANE SANDY FORECAST
TO PUSH DUE WEST ACROSS SOUTHERN PA MONDAY NIGHT INTO TUESDAY
PERIODS OF STRONG WINDS MONDAY NIGHT AND TUESDAY COULD BE
SUSTAINED NEAR 35 KNOTS WITH GUSTS OF 55 TO 60 KNOTS POSSIBLE
BEFORE THE STORM WEAKENS TUESDAY. PERIODS OF INTENSE RAINFALL
CAN ALSO BE EXPECTED DURING THE MONDAY NIGHT INTO TUESDAY
PERIOD. AS THE STORM WEAKENS AND MOVE NORTH TUESDAY NIGHT
INTO WEDNESDAY. WINDS WILL DIMINISH BUT GUSTS OF 25 TO 35 KNOTS
ARE POSSIBLE EVEN INTO WEDNESDAY AFTERNOON. RAINFALL WILL DIMINISH
RAPIDLY WEDNESDAY.
&&
.HYDROLOGY...
AS MENTIONED ABOVE...RAINFALL TOTALS THROUGH EARLY WEDNESDAY ARE
FORECAST IN THE 2 TO 4.5 INCH RANGE FOR THE MONONGAHELA AND
ALLEGHENY RIVER BASINS. FORECAST MODELS IN THE HANDLING OF THIS
SYSTEMS ACTUAL TRACK. GUIDANCE FROM THE HYDROMETEOROLOGICAL
PREDICTION CENTER HAS GENERALLY THE SAME AREA IN EXCESS OF THREE
INCHES ACROSS THOSE SAME AREAS.
SHOULD EITHER OF THESE TOTAL BE REALIZED ON A WIDESPREAD BASIS...THEN
SMALL STREAM FLOODING WOULD OCCUR BY LATER ON MONDAY AND INTO
TUESDAY...WITH RIVER RISES LATE TUESDAY AND WEDNESDAY...WITH FLOODING
FOLLOWING IF MAXIMUM AMOUNTS ARE REALIZED.
FOR NOW...A MENTION OF SUCH POTENTIAL WILL BE INCLUDED IN THE
HAZARDOUS WEATHER OUTLOOK. ADDITIONAL PRODUCTS WILL FOLLOW DURING
THE NEXT FEW DAYS SHOULD THE SITUATION MATERIALIZE FURTHER.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
MDZ001.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR MDZ001.
OH...FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
OHZ039>041-048>050-057>059-068-069.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR OHZ039>041-048>050-057>059-068-069.
PA...FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
PAZ007>009-013>016-020>023-029-031-073>076.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR PAZ007>009-013>016-020>023-029-031-073>076.
WV...FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
WVZ001>004-012-021>023-041.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR WVZ001>004-012-021>023-041.
&&
$$
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 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 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
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
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 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 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
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 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 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 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
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
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 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 PITTSBURGH PA
427 AM EDT SUN OCT 28 2012
.SYNOPSIS...
THE INTERACTION BETWEEN THE FRONT STALLED OVER THE UPPER OHIO
VALLEY REGION AND POST HURRICANE SANDY WILL LEAD TO WIND...RAIN
WITH THE POSSIBILITY OF FLOODING...AND ACCUMULATING SNOW FOR THE
RIDGES.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY MORNING POPS WERE INITIALLY ADJUSTED DOWNWARD BASED ON THE
LATEST RADAR TRENDS...HOWEVER...RAIN CHANCES ARE EXPECTED TO
INCREASE STEADILY AS MOISTURE CONTINUES TO CONVERGE INTO THE DEEP
BAROCLINIC ZONE IN PLACE OVER THE REGION. PERI DAWN POPS WERE
STRUCTURED USING A BLEND OF THE HRRR AND NAM MODELS AND COMBINED
WITH ONGOING AREAS OF DRIZZLE WITH FOG ON THE RIDGES.
THE FORECAST FOR THE REST OF THE DAY BASICALLY FEATURES A CONTINUED
ESCALATION OF PCPN CHANCES. TEMPERATURE ADJUSTMENTS WERE MINIMAL
AND THAT PROGNOSIS WAS BASED ON A BLEND OF THE LATEST SREF MEANS
WITH PERSISTENCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
ADJUSTMENTS TO THE SHORT TERM PERIOD...FEATURING THE DEVELOPMENT
OF POST HURRICANE/TROPICAL STORM SANDY ACRS PENNSYLVANIA...WERE
PRIMARILY COSMETIC.
PERIODS OF RAIN MAY BECOME HEAVY BY MONDAY AND WIND WILL INCREASE
AS THE PRESSURE GRADIENT TIGHTENS. THE FLOOD AND HIGH WIND WATCHES
HAVE BEEN MAINTAINED. IN ADDITION...THE LATEST GFS...NAM...AND
ECMWF SOLUTIONS ARE WRAPPING SUFFICIENTLY COLD AIR FOR A CHANGE
TO SNOW LATER ON MONDAY OVER THE RIDGES OF WEST VIRGINIA AND
MARYLAND. SIGNIFICANT SNOW ACCUMULATIONS ARE POSSIBLE THERE
THROUGH TUESDAY NIGHT AND A WINTER STORM WATCH WAS ISSUED...AND
WORDED FOR HIGHER ELEVATIONS IN THE TRI COUNTY AREA TO THE SOUTH
OF OAKLAND OF GARRETT COUNTY.
ELSEWHERE...BOUNDARY LAYER TEMPERATURES WILL PROBABLY REMAIN
SUFFICIENTLY WARM TO PRECLUDE SNOW...OR ACCUMULATION FOR AREAS
WHERE SNOW MIXES WITH THE RAIN.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
THE STRONG LOW RESULTING FROM THE PHASING OF POST TROPICAL STORM
SANDY AND THE COLD UPPER TROUGH WILL BE SLOW TO EXIT NORTH THIS
PERIOD. DUE TO ALL THE UNCERTAINTY...HAVE CONTINUED MENTION OF A
CHANCE OF RAIN SHOWERS INTO FRIDAY WITH SNOW SHOWERS POSSIBLE
ACROSS THE HIGHER WV-MD MOUNTAINS.
FORECASTED CONTINUED COLDER THAN NORMAL TEMPERATURES BASED ON
RECENT GFS AND ECMWF MODEL OUTPUT. ONCE THE COLD LOW CENTER
EXITS...DRYING WILL BEGIN AND TEMPERATURES COULD REBOUND TOWARD
NORMAL VALUES NEXT WEEKEND.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
A FRONTAL BOUNDARY WILL REMAIN JUST EAST OF A KLBE-KDUJ LINE THROUGH
THE TAF PERIOD. IN THE VICINITY OF THE FRONT...IFR AND LOWER
CEILINGS WILL PREVAIL EVERYWHERE EXCEPT KZZV THIS MORNING. MVFR
CEILINGS WILL CONTINUE TO PREVAIL AT KZZV. INTERMITTENT SHOWERS WITH
MVFR VISIBILITIES WILL PUSH SLOWLY NORTHWESTWARD OF KPIT THIS
MORNING.
AFTER 14Z...CEILINGS WILL BEGIN TO LIFT BACK TO MVFR. SCATTERED
SHOWERS WITH MVFR VISIBILITY RESTRICTIONS WILL CONTINUE THROUGH
THE REMAINDER OF THE TAF PERIOD AS THE FRONT REMAINS STALLED AND
MOISTURE FROM SANDY BEGINS TO PUSH INTO THE AREA FROM THE EAST.
WINDS WILL BE NORTHERLY AROUND 10KTS THROUGH THE TAF PERIOD.
.OUTLOOK.../MONDAY THROUGH THURSDAY/...
THE REMNANTS OF SANDY WILL MERGE WITH AN UPPER TROUGH...BRINGING
FREQUENT MVFR TO IFR RESTRICTIONS WITH RAIN THROUGH THIS PERIOD.
WHEN THE REMNANT SURFACE LOW FROM SANDY NEARS THE AREA LATE MONDAY
INTO TUESDAY...WINDS WILL INCREASE TO 20-25KTS WITH GUSTS TO 40KTS
POSSIBLE. IN ADDITION...STRONG LOW-LEVEL WIND SHEAR WILL OCCUR
MONDAY NIGHT INTO EARLY TUESDAY. THE STORM WILL WEAKEN AND MOVE
NORTH TUESDAY NIGHT INTO WEDNESDAY...WITH MORE SCATTERED SHOWERS
INTO THURSDAY.
&&
.HYDROLOGY...
RAINFALL TOTALS THROUGH EARLY WEDNESDAY WERE BASED ON THE LATEST
ECMWF...NAM...AND GFS GUIDANCE...AND ARE CONSERVATIVELY FORECAST
IN THE 2 TO 3 INCH RAIN FOR THE MONONGAHELA AND ALLEGHENY RIVER
BASINS. GUIDANCE FROM THE HYDROMETEOROLOGICAL PREDICTION CENTER
REMAINS IN EXCESS OF THREE INCHES ACROSS THOSE SAME AREAS.
SHOULD EITHER OF THESE TOTAL BE REALIZED ON A WIDESPREAD BASIS...THEN
SMALL STREAM FLOODING WOULD OCCUR BY LATER ON MONDAY AND INTO
TUESDAY...WITH RIVER RISES LATE TUESDAY AND WEDNESDAY. RIVER
FLOODING WOULD FOLLOW DURING THE LATTER HALF OF THE WEEK IF THE
HIGHER AMOUNTS OCCUR.
FOR NOW...A FLOOD WATCH FOR SMALL STREAM FLOODING IS IN EFFECT
THROUGH TUESDAY...AND THE POTENTIAL FOR RIVER FLOODING WILL BE
INCLUDED IN THE HAZARDOUS WEATHER OUTLOOK. ADDITIONAL PRODUCTS
WILL FOLLOW DURING THE NEXT FEW DAYS AS THE SITUATION MATURES.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
MDZ001.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR MDZ001.
WINTER STORM WATCH FROM MONDAY EVENING THROUGH WEDNESDAY
MORNING FOR MDZ001.
OH...FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
OHZ039>041-048>050-057>059-068-069.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR OHZ039>041-048>050-057>059-068-069.
PA...FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
PAZ007>009-013>016-020>023-029-031-073>076.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR PAZ007>009-013>016-020>023-029-031-073>076.
WV...FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
WVZ001>004-012-021>023-041.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR WVZ001>004-012-021>023-041.
WINTER STORM WATCH FROM MONDAY EVENING THROUGH WEDNESDAY
MORNING FOR WVZ023-041.
&&
$$
15/02
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
114 AM EDT SUN OCT 28 2012
.SYNOPSIS...
THE INTERACTION BETWEEN THE FRONT STALLED OVER THE UPPER OHIO
VALLEY REGION AND THE NORTHBOUND HURRICANE SANDY WILL LEAD TO
WINDY CONDITIONS...RAIN WITH THE POSSIBILITY OF FLOODING...AND
ACCUMULATING SNOW FOR THE RIDGES.
&&
.NEAR TERM /THROUGH TODAY/...
OVERNIGHT POPS WERE INITIALLY ADJUSTED DOWNWARD BASED ON THE
LATEST RADAR TRENDS...HOWEVER RAIN CHANCES ARE EXPECTED TO
INCREASE AS MOISTURE CONTINUES TO CONVERGE INTO THE DEEP
BAROCLINIC ZONE IN PLACE OVER THE REGION. PERI DAWN POPS WERE
STRUCTURED USING A BLEND OF THE HRRR AND NAM MODELS...AND
BASICALLY FEATURE A REESCALATION OF PCPN CHANCES AS THE MRNG...AND
AS THE DAY PROGRESS.
TEMPERATURE ADJUSTMENTS WERE MINIMAL AND FORECAST IS BASED ON A
BLEND OF THE LATEST SREF MEANS WITH PERSISTENCE.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
ADJUSTMENTS TO THE SHORT TERM PERIOD...FEATURING THE DEVELOPMENT
OF POST TROPICAL STORM SANDY ACRS PENNSYLVANIA...WERE PRIMARILY COSMETIC.
PERIODS OF RAIN MAY BECOME HEAVY BY MONDAY AND WIND WILL INCREASE
AS THE PRESSURE GRADIENT TIGHTENS. THE FLOOD AND HIGH WIND WATCHES
HAVE BEEN MAINTAINED. IN ADDITION...THE LATEST GFS AND NAM
SOLUTIONS ARE WRAPPING SUFFICIENTLY COLD AIR FOR A CHANGE TO SNOW
LATER ON MONDAY OVER THE RIDGES OF WEST VIRGINIA AND MARYLAND.
ACCUMULATING SNOW SHOULD BE ANTICIPATED THERE THROUGH TUESDAY AND
FURTHER ATTENTION TO THAT SITUATION WILL BE FORTHCOMING.
ELSEWHERE...BOUNDARY LAYER TEMPERATURES WILL PROBABLY REMAIN
SUFFICIENTLY WARM TO PRECLUDE SNOW...OR ACCUMULATION FOR AREAS
WHERE SNOW MIXES WITH THE RAIN.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE STRONG LOW RESULTING FROM THE PHASING OF HURRICANE SANDY AND
THE COLD UPPER TROUGH WILL BE SLOW TO EXIT NORTH THIS PERIOD. DUE
TO ALL THE UNCERTAINTY HAVE CONTINUED MENTION OF A CHANCE OF
RAIN SHOWERS INTO FRIDAY WITH SNOW SHOWERS POSSIBLE ACROSS THE
HIGHER WV-MD MOUNTAINS.
FORECASTED CONTINUED COLDER THAN NORMAL TEMPERATURES BASED ON
RECENT GFS AND ECMWF MODEL OUTPUT. ONCE THE COLD LOW CENTER
EXITS...DRYING WILL BEGIN AND TEMPERATURES COULD REBOUND TOWARD
NORMAL VALUES NEXT WEEKEND.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
A FRONTAL BOUNDARY WILL REMAIN JUST EAST OF A KLBE-KDUJ LINE THROUGH
THE TAF PERIOD. IN THE VICINITY OF THE FRONT...IFR AND LOWER
CEILINGS WILL PREVAIL AT KLBE-KMGW-KDUJ INTO THE EARLY AFTERNOON
TODAY. CEILINGS WILL LOWER TO IFR THROUGH DAWN AT THE REMAINING
TERMINALS OTHER THAN KZZV. MVFR CEILINGS WILL CONTINUE TO PREVAIL AT
KZZV. IN ADDITION...PERIODS OF DRIZZLE WITH MVFR VISIBILITIES AT
TIMES WILL BE POSSIBLE EVERYWHERE EXCEPT KZZV.
AFTER 14Z...CEILINGS WILL BEGIN TO LIFT BACK TO MVFR. SCATTERED
SHOWERS WITH BRIEF MVFR VISIBILITIES RESTRICTIONS WILL CONTINUE
THROUGH THE REMAINDER OF THE TAF PERIOD AS THE FRONT REMAINS STALLED
AND MOISTURE FROM SANDY BEGINS TO PUSH INTO THE AREA FROM THE
EAST.
WINDS WILL BE NORTHERLY AROUND 10KTS THROUGH THE TAF PERIOD.
.OUTLOOK.../MONDAY THROUGH THURSDAY/...
THE REMNANTS OF SANDY WILL MERGE WITH AN UPPER TROUGH...BRINGING
FREQUENT MVFR TO IFR RESTRICTIONS WITH RAIN THROUGH THIS PERIOD.
WHEN THE REMNANT SURFACE LOW FROM SANDY NEARS THE AREA LATE MONDAY
INTO TUESDAY...WINDS WILL INCREASE TO 20-25KTS WITH GUSTS TO 40KTS
POSSIBLE. IN ADDITION...STRONG LOW-LEVEL WIND SHEAR WILL OCCUR
MONDAY NIGHT INTO EARLY TUESDAY. THE STORM WILL WEAKEN AND MOVE
NORTH TUESDAY NIGHT INTO WEDNESDAY...WITH MORE SCATTERED SHOWERS
INTO THURSDAY.
&&
.HYDROLOGY...
AS MENTIONED ABOVE...RAINFALL TOTALS THROUGH EARLY WEDNESDAY ARE
FORECAST IN THE 2 TO 4.5 INCH RANGE FOR THE MONONGAHELA AND
ALLEGHENY RIVER BASINS. GUIDANCE FROM THE HYDROMETEOROLOGICAL
PREDICTION CENTER IS IN EXCESS OF THREE INCHES ACROSS THOSE SAME
AREAS.
SHOULD EITHER OF THESE TOTAL BE REALIZED ON A WIDESPREAD BASIS...THEN
SMALL STREAM FLOODING WOULD OCCUR BY LATER ON MONDAY AND INTO
TUESDAY...WITH RIVER RISES LATE TUESDAY AND WEDNESDAY...WITH FLOODING
FOLLOWING IF MAXIMUM AMOUNTS ARE REALIZED.
FOR NOW...A FLOOD WATCH FOR SMALL STREAM FLOODING IS IN EFFECT
THROUGH TUESDAY...AND THE POTENTIAL FOR LATER RIVER FLOODING WILL
BE INCLUDED IN THE HAZARDOUS WEATHER OUTLOOK. ADDITIONAL PRODUCTS
WILL FOLLOW DURING THE NEXT FEW DAYS AS THE SITUATION MATURES.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
MDZ001.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR MDZ001.
OH...FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
OHZ039>041-048>050-057>059-068-069.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR OHZ039>041-048>050-057>059-068-069.
PA...FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
PAZ007>009-013>016-020>023-029-031-073>076.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR PAZ007>009-013>016-020>023-029-031-073>076.
WV...FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
WVZ001>004-012-021>023-041.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY EVENING
FOR WVZ001>004-012-021>023-041.
&&
$$
15/02
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
448 AM EDT SUN OCT 28 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 446 AM EDT SUN OCT 28 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF EXTENDING FROM
MANITOBA S THRU THE MISSISSIPPI VALLEY. MINOR SHORTWAVE AND
ASSOCIATED INVERTED SFC TROF ACROSS SD INTO NRN MN IS AIDING AN
AREA OF SNOW OVER NRN MN. OTHERWISE...IT`S A QUIET NIGHT WEATHER
WISE ACROSS THE UPPER GREAT LAKES. SFC HIGH PRES IS COVERING THE
AREA FROM SRN SASKATCHEWAN/MANITOBA INTO THE UPPER GREAT LAKES...
RESULTING IN LIGHT/CALM WIND ACROSS UPPER MI EARLY THIS MORNING.
WITH 850MB TEMPS AROUND -9C...OVERWATER INSTABILITY IS SUFFICIENT
FOR LES...BUT SFC BASED WELL-MIXED LAYER EVIDENT ON UPSTREAM 00Z
KINL SOUNDING IS A BIG NEGATIVE. AS A RESULT...KMQT RADAR HAS ONLY
HINTED AT SOME SPRINKLES/FLURRIES OVER ERN LAKE SUPERIOR INTO NE
UPPER MI DURING THE OVERNIGHT. NOTHING MORE THAN SOME HIGH CLOUDS
ACROSS PORTIONS OF THE W AND CNTRL FCST AREA HAS ALLOWED TEMPS TO
PLUMMET INTO THE UPPER TEENS IN SOME OF THE TRADITIONAL COLD SPOTS.
QUIET WEATHER WILL BE THE RULE IN THE SHORT TERM HAS SFC HIGH PRES
DOMINATES THE AREA. THE AREA OF SNOW IN NRN MN WILL WEAKEN AND LIFT
NE TODAY...PASSING W OF THE FCST AREA. MEANWHILE...IF THERE ARE ANY
SPRINKLES/FLURRIES MOVING ONSHORE TO THE E OF MARQUETTE...THOSE WILL
DISSIPATE BY AFTN AS AIRMASS MODIFIES SLIGHTLY. IN THE END...EXPECT
A MIX OF CLOUDS AND SUN WITH TEMPERATURES RISING TO 40-45...WARMEST
SCNTRL.
WITH ANOTHER NIGHT OF LIGHT/CALM WIND...FAVORED THE LOWER SIDE OF
GUIDANCE TONIGHT FOR MINS. TEMPS SHOULD FALL BACK TO THE MID/UPPER
TEENS IN THE TRADITIONAL COLDS SPOTS OVER THE W HALF INTERIOR.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 446 AM EDT SUN OCT 28 2012
MAIN SHOW FOR THE LONG TERM IS WITH REMNANTS OF HURRICANE SANDY
MOVING INTO THE CWA TUE AND WED...WITH LITTLE TO NO SIGNIFICANT
CHANGES TO FORECAST THINKING FROM THE LAST COUPLE OF SHIFTS.
STARTING WITH MON...THINGS LOOKS PRETTY QUIET OVER THE CWA AS A SFC
RIDGE SITS OVER UPPER MI. NO SIGNIFICANT PRECIP IS EXPECTED MON AND
MON NIGHT.
SANDY MAKES LANDFALL LATE MON INTO MON NIGHT OVER OR NEAR NJ...THE
SYSTEM THEN SPINS OVER SE PA THROUGH 06Z WED BEFORE SHIPPING N TO
FAR SRN QUEBEC BY 12Z THU. MOISTURE WILL WRAP AROUND THE SYSTEM AS
THE SYSTEM PUSHES THE SFC RIDGE AXIS FROM OVER THE CWA TO JUST NW OF
THE CWA. BEING BETWEEN THE LOW AND THE RIDGE WILL KEEP WINDS
GENERALLY NLY/NELY TUE AND WED AS THE PRESSURE GRADIENT INCREASES.
THE TRICKIEST PART OF THE FORECAST WITH THIS SYSTEM WILL BE THE
PRECIP CUT OFF OVER THE W CLOSER TO THE SFC RIDGE AND AN UPPER
RIDGE...AND PRECIP TYPE AS MODELS SHOW A RIBBON OF COLDER AIR OVER
THE CENTRAL CWA THAT WOULD BE SUPPORTIVE OF SNOW. WILL FOCUS IN A
BIT MORE ON THESE DETAILS.
FOR PRECIP CHANCES...DEEP MOISTURE WILL FIRST ROTATE INTO THE CWA
FROM E TO W AROUND 12Z TUE AND WILL REACH PEAK DEPTH INTO THE CWA
WED EVENING. QUESTION IS HOW FAR W WILL THE MOISTURE GO. ALL MODELS
SHOW A SHARP CUT OFF FROM NEAR 100 PERCENT 1000-700MB RH EAST TO
LESS THAN 20 PERCENT RH WEST. THE 00Z/28 GFS IS THE FARTHEST W WITH
THE CUT OFF...BRINGING HIGHER RH VALUES OVER ALL OF THE CWA...WHILE
THE 12Z/27 ECMWF IS ON THE E SIDE OF GUIDANCE WITH THE TRANSITION
FROM MOIST TO DRY OVER THE CENTRAL CWA. THE 00Z/28 NAM IS MORE IN
BETWEEN THE GFS AND ECMWF WITH THE CUT OFF CLOSER TO THE ECMWF THAN
THE GFS. LIKE THE PREVIOUS FORECAST POPS THAT COVER WRN UPPER MI IN
SLIGHT CHANCE POPS AND HAVE LIKELY POPS OVER NCENTRAL AND ERN UPPER
MI. GIVEN THE GOOD MOISTURE OVER AT LEAST THE ERN HALF OF THE
CWA...STRONG CYCLONIC NNELY FLOW /AND RESULTING UPSLOPE FLOW IN
HIGHER TERRAIN AREAS/ AND COOL 900-850MB TEMPS THAT WILL RESULT IN
DELTA T VALUES AROUND 7-10C THESE LIKELY POPS ARE CERTAINLY
JUSTIFIED...AND WILL INCREASE THESE SOME.
BEST CHANCES FOR MIXED PRECIP WILL BE TUE NIGHT AS NEAR SFC TEMPS
COOL INTO THE LOW TO MID 30S UNDER THE SUB-FREEZING LAYERS ABOVE
OVER THE NCENTRAL CWA. OVER THE E...WARMER AIR WILL WRAP AROUND THE
SYSTEM AT AROUND 800MB...AND SHOULD BE DEEP AND WARM ENOUGH TO KEEP
MOST PRECIP RAIN. HOWEVER...OVER THE ERN CWA...SOME OF THE PRECIP
COULD FALL AS SLEET BEFORE THE DEEPER WARM AIR ARRIVES SINCE 900MB
TEMPS WILL BE AROUND -3C. BACK TO THE NCENTRAL...ESPECIALLY THE
HIGHER TERRAIN...IT APPEARS PRECIP WILL LIKELY BE ALL SNOW TUE NIGHT
INTO EARLY WED. AGREE THAT BEST BET FOR SNOWFALL AMOUNTS LOOKS TO BE
ON THE LOW SIDE IN THE 1-3 INCH RANGE GIVEN THAT THE SNOW GROWTH
ZONE WILL BE AT 550-500MB AND OUT OF THE BEST LIFT FROM UPSLOPE/LAKE
ENHANCEMENT AND THAT SFC TEMPS WILL BE NEAR OR ABOVE FREEZING.
STILL...THERE IS POTENTIAL FOR INCREASED SNOWFALL AMOUNTS IF ALL
FACTORS LINE UP. THIS WOULD LIKELY CAUSE SOME SLOPPY DRIVING
CONDITIONS FOR THE WED MORNING COMMUTE SO WILL KEEP MENTION IN THE
HWO.
WINDS WILL BE ANOTHER IMPORTANT ASPECT WITH THIS SYSTEM. 925MB WINDS
GREATER THAN 30KTS MOVES IN FROM E TO W LATE MON INTO MON
NIGHT...WITH 925MB WINDS OF 40-45KTS OVER ERN UPPER MI FROM AROUND
09Z TUE TO AROUND 06Z WED. THESE HIGHER WINDS SHOULD HAVE A BETTER
CHANCE AT MIXING TO THE SFC OVER LAND DURING THE DAY ON TUE BUT
EXPECT MOST GUSTS TO BE 40MPH OR LESS...WITH POTENTIAL FOR SOME
50MPH GUSTS. OVER LAKE SUPERIOR AND NW LAKE MI...EXPECT GUSTS TO
REMAIN BELOW 40KTS SINCE WE WILL SEE WARM ADVECTION AND THE SYSTEM
WILL BE WEAKENING...NOT THE TYPICAL SIGNAL FOR STRONG LAKE WINDS.
ECMWF MOVES THE PRECIP OUT BY LATE WED NIGHT WHILE THE GFS KEEP
PRECIP INTO EARLY THU AFTERNOON. WILL GO CLOSER TO THE PREVIOUS
FORECAST AND THE ECMWF FOR POPS ON THU.
UNCERTAINTY INCREASES FOR FRI AND SAT...AND WITH HIGHER IMPACT
EARLIER IN THE WEEK...JUST USED CONSENSUS OF MODELS FOR THE LATER
PERIODS OF THE FORECAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 122 AM EDT SUN OCT 28 2012
WITH WEAK HIGH PRESSURE IN PLACE THROUGH THE FORECAST...VFR CEILINGS
AND VISIBILITIES WILL REMAIN THE RULE. WEAK ENERGY ROTATING AROUND
LOW PRESSURE ALOFT WEST OF THE AREA WILL BRING IN CLOUD COVER...BUT
CIGS WILL STAY AOA MVFR CONDITION. EXPECT WINDS TO REMAIN LIGHT
THROUGH THE FORECAST WITH SPEEDS BELOW 10 KNOTS...WITH THE HIGHEST
SPEEDS AT KSAW WHERE NORTH WINDS PICK UP SLIGHTLY AS PRESSURE
GRADIENT BEGINS TO TIGHTEN BETWEEN THE SYSTEM APPROACHING THE EAST
COAST AND THE HIGH PRESSURE OVERHEAD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 446 AM EDT SUN OCT 28 2012
HIGH PRES RIDGE EXTENDING S THRU CNTRL LAKE SUPERIOR TODAY/TONIGHT
AND THEN DRIFTING W TO WRN LAKE SUPERIOR MON WILL LEAD TO LIGHT
WINDS UNDER 20KT. PRES GRADIENT WILL TIGHTEN A BIT OVER THE FAR E
MON...SO WINDS THERE SHOULD RISE UP TO 15-25KT. MON NIGHT THRU
THU...THE HIGH PRES RIDGE WILL DRIFT A LITTLE FARTHER W.
MEANWHILE...POWERFUL LOW PRESSURE MOVING ONSHORE OVER THE MID
ATLANTIC STATES MONDAY NIGHT WILL WEAKEN AS IT MOVES TO THE LOWER
GREAT LAKES LATE WEDNESDAY AND INTO SOUTHERN QUEBEC THURSDAY.
ALTHOUGH WEAKENING...TIGHTENING PRES GRADIENT AND EXPANDING WIND
FIELD AROUND STORM SYSTEM WILL LIKELY LEAD TO NORTHERLY GALES OVER
ROUGHLY THE E HALF OF LAKE SUPERIOR MON NIGHT THRU EARLY WED. A FEW
FACTORS WILL KEEP WINDS IN CHECK. FIRST...SYSTEM WILL BE WEAKENING
QUICKLY AFTER IT MOVES ONSHORE OVER THE MID ATLANTIC STATES.
SECOND...THERE ARE NO STRONG DYNAMICS AFFECTING THE UPPER GREAT
LAKES...AND THIRD THERE IS NO CAA. SO...PROBABLY WON`T SEE GALES
OVER 35-40KT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM MONDAY EVENING THROUGH WEDNESDAY MORNING FOR
LSZ251-267.
GALE WATCH FROM LATE MONDAY NIGHT THROUGH WEDNESDAY MORNING FOR
LSZ249-250-266.
LAKE MICHIGAN...
GALE WATCH FROM MONDAY EVENING THROUGH WEDNESDAY MORNING FOR
LMZ221-248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...KEC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
359 AM EDT SUN OCT 28 2012
.SYNOPSIS...
HURRICANE SANDY WILL MOVE ONSHORE OVER NEW JERSEY ON MONDAY NIGHT
AND THEN TRACK ACROSS CENTRAL PENNSYLVANIA TO NEW YORK TUESDAY AND
WEDNESDAY. THIS LARGE STORM WILL DOMINATE THE WEATHER ACROSS
NORTHERN OHIO AND NORTHWEST PENNSYLVANIA FOR MUCH OF THE COMING
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
DRIZZLE AND PATCHY LIGHT RAIN ACROSS NERN OHIO AND NWRN PA
OVERNIGHT HOWEVER RADAR SHOWS DEVELOPING SHOWERS ACROSS SOUTHEAST
OHIO MOVING NORTH. THIS AREA OF SHOWERS CONNECTS TO DEVELOPING
SHOWERS FROM PITTSBURGH NORTHEAST INTO NEW YORK. THE HRRR SHOWS
THIS ENTIRE LINE CONTINUING TO EXPAND THROUGH THE EARLY MORNING
HOURS...FILLING IN ACROSS NORTHEAST OHIO AND NWRN PA ESPECIALLY
AROUND OR JUST AFTER DAWN. THIS WILL THEN EXPAND/DRIFT WEST INTO
NORTH CENTRAL OHIO BY 18Z. WILL HAVE THE FAR NWRN CORNER
DRY...UNLESS THE FORMATTER GRABS ONTO A PIXEL OF SLIGHT
CHANCE...AND THEN QUICKLY RAMP UP TO CAT POPS ALONG AND EAST OF A
LORAIN TO MFD LINE. HIGH TEMPS UPPER 40S TO AROUND 50.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
SHORT TERM PERIOD WILL BE QUITE ACTIVE WITH THE REMNANTS OF SANDY
MOVING THROUGH PA INTO NEW YORK MONDAY NIGHT THROUGH WEDNESDAY
ALTHOUGH BY WEDNESDAY THE WIND FIELD WEAKENS CONSIDERABLY.
FOLLOWED THE NAM12 THROUGH MUCH OF THE SHORT TERM PERIOD. TO BE
BRIEF...POPS WILL BE CATEGORICAL FOR MOST OF THE SHORT TERM PERIOD
ACROSS THE EASTERN TWO THIRDS OF THE AREA. THE WESTERN THIRD WILL
BE CLOSER TO THE DRY AIR AND WILL WAVER BETWEEN SLIGHT CHANCE AND
LIKELY DEPENDING ON MOISTURE DEPTH ON THE NAM. BIG PROBLEM WILL BE
OF COURSE THE WIND AND FLOOD POTENTIAL WITH THE STORM. WILL
CONTINUE WITH THE HIGH WIND WATCH AS GUIDANCE CONTINUES TO SUPPORT
WINDS OF 30 TO 30 MPH WITH GUSTS TO /OVER 50 KNOTS. AREA WHERE NO
HIGH WIND WATCH IS IN EFFECT COULD STILL SEE WIND ADVISORY
CRITERIA SO WILL NEED TO CONTINUE TO MONITOR FOR THE POSSIBILITY.
BASED ON NUMERICAL GUIDANCE...HIGHEST WIND TIMING WOULD BE MONDAY
NIGHT THROUGH TUESDAY MID/LATE AFTERNOON. ALSO CONTINUE TO LIKE THE
FLOOD WATCH PLACEMENT. 5 DAY FORECAST FROM HPC IS 3 TO 4+ INCHES
ACROSS NORTHEAST OHIO AND NWRN PA. SIMILAR TO THE WIND
TIMING...BEST POTENTIAL FOR HEAVY RAIN WILL COME MONDAY NIGHT AND
POSSIBLY INTO EARLY TUESDAY. ALSO GIVEN THE WAVES EXPECTED ON LAKE
ERIE COMBINED WITH THE FACT THAT WINDS WILL BE FROM THE NORTH FOR
A GOOD PORTION OF THE STORM...WILL ISSUE A LAKESHORE FLOOD WATCH.
HIGH TEMPS IN THE 40S TO NEAR 50. LOWS IN THE 30S. JUST AN ASIDE
HERE...850MB TEMPS DO DROP TO -3C OR SO ACROSS THE WESTERN
COUNTIES LATE SUNDAY NIGHT AND AGAIN MONDAY NIGHT BUT
REALLY...THIS TIME OF YEAR...WOULD PREFER LOWER 850MB TEMPS BEFORE
FORECASTING SNOW. SO FOR NOW WILL KEEP PRECIP ALL RAIN.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
BEGINNING THURSDAY...THE REMNANT LOW FROM SANDY WILL BEGIN MOVING
AWAY TO THE NORTHEAST...BUT CYCLONIC FLOW WITH TROUGH STILL OVER THE
AREA WILL ALLOW FOR CLOUDS AND SCATTERED SHOWERS...BEST CHANCE
ACROSS NE OH/NW PA...TO CONTINUE. KEPT LIKELY POPS ACROSS THE
NORTHEAST WITH CHC TRENDING BACK TO THE SOUTH AND WEST. LOOKS LIKE
FRIDAY WILL BEGIN THE TRANSITION LOSING THE INFLUENCE OF THE LOW AND
UPPER TROUGH WITH RIDGING ALOFT BUILDING IN. DIDN/T WANT TO GET TOO
SPECIFIC GIVEN HOW FAR OUT...BUT THINKING POPS MENTIONED IN THE
FORECAST FOR FRIDAY...ESPECIALLY ACROSS THE EAST MAY BE MORE DURING
THE MORNING WITH IMPROVING IN THE AFTERNOON. CLOUDS BUILD BACK INTO
THE AREA FRIDAY NIGHT WITH A WARM FRONT MOVING ACROSS THE AREA. WENT
WITH DRY CONDITIONS FOR SAT AT THIS POINT...BUT LOOKS LIKE PRECIP
WILL BE QUICKLY BUILDING TOWARD THE AREA LATE IN THE DAY. OVERALL
MADE ADJUSTMENTS TO PREVIOUS FORECAST TEMPS COMPARED TO MEX GUIDANCE.
&&
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
RADAR NOT SHOWING MUCH BUT OBS INDICATING SOME AREAS OF DZ OR -RA
ACROSS SITES. WESTERN SITES WILL REMAIN MAINLY VFR...BUT BRING
CIGS DOWN AROUND 035 LATE IN AFTERNOON. MODELS SHOWING VFR THERE
THROUGH THE PERIOD...BUT LOOKS LIKE IT WILL BE A SHARP CUTOFF
ACROSS THE WEST BETWEEN VFR AND MVFR.
FURTHER EAST...MVFR AND IFR CONDITIONS WILL PERSIST THROUGH
TONIGHT WITH SOME SCATTERED DRIZZLE OR SHOWERS. MVFR AND IFR WILL
CONTINUE THROUGH SUNDAY WITH CONDITIONS DETERIORATING LATE MORNING
AND AFTERNOON AS MOISTURE BUILDS BACK WEST INTO NRN OH. MVFR SITES
WILL EVENTUALLY DROP TO IFR WITH RAIN ALSO BUILDING BACK WESTWARD.
WINDS WILL CONTINUE TO BE GUSTY FROM THE N AND NE THROUGH SUNDAY.
SUSTAINED WINDS AROUND 15KT WITH GUSTS TO 25KT LIKELY.
.OUTLOOK...NON-VFR NRN OH/NW PA SUNDAY NIGHT INTO MONDAY. NON-VFR
MOST AREAS TUESDAY AND WEDNESDAY.
&&
.MARINE...
NORTHERLY WINDS ARE EXPECTED TO GRADUALLY INCREASE TOWARD 30 KNOTS
BY LATE TODAY. WINDY CONDITIONS WITH HIGH WAVES WILL CONTINUE
THROUGH THE FORECAST PERIOD. NO CHANGES TO HEADLINES WITH THIS
FORECAST ISSUANCE WITH MODELS CONTINUING TO SHOW THE POSSIBILITY FOR
STORM FORCE WINDS ON THE LAKE MONDAY NIGHT THROUGH EARLY TUESDAY
AFTERNOON. OVERALL MADE ONLY SMALL ADJUSTMENTS TO WINDS...BUT NEW
GUIDANCE CONSISTENT WITH PREVIOUS FORECAST AND SEE LITTLE REASON TO
ADJUST IN EITHER DIRECTION. WAVES WILL BE SIGNIFICANT ACROSS THE
LAKE FROM LATE MONDAY THROUGH MIDDAY TUESDAY...WITH 18 FEET A STRONG
POSSIBILITY. WINDS ARE EXPECTED TO SUBSIDE BELOW GALE FORCE THROUGH
TUESDAY NIGHT AND EARLY WEDNESDAY WHILE SHIFTING TO THE NORTHWEST.
WINDS WILL TURN TO THE WEST THROUGH WEDNESDAY. SMALL CRAFT
CONDITIONS ARE EXPECTED TO DIMINISH FROM WEST TO EAST ON FRIDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...FLOOD WATCH FROM LATE TONIGHT THROUGH TUESDAY EVENING FOR
OHZ010>014-020>023-031>033-038-089.
LAKESHORE FLOOD WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY
EVENING FOR OHZ003-007>012-089.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING
FOR OHZ009>014-019>023-029>033-038-089.
PA...FLOOD WATCH FROM LATE TONIGHT THROUGH TUESDAY EVENING FOR
PAZ001>003.
LAKESHORE FLOOD WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY
EVENING FOR PAZ001.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING
FOR PAZ001>003.
MARINE...STORM WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING FOR
LEZ061-142>149-162>169.
SMALL CRAFT ADVISORY UNTIL NOON EDT MONDAY FOR LEZ142>149.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK
SHORT TERM...TK
LONG TERM...ABE
AVIATION...ABE
MARINE...ABE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
222 AM CDT SUN OCT 28 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
222 AM CDT SUN OCT 28 2012
MAIN FORECAST CONCERNS REMAIN ON CLOUDS AND TEMPERATURES WITH THE
BLOCKED WEATHER PATTERN IN PLACE.
CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING ALONG THE WEST COAST OF THE U.S....TROUGHING FROM
MANITOBA SOUTH THROUGH THE FORECAST AREA AND INTO ARKANSAS...STRONG
RIDGING OVER NEWFOUNDLAND AND HURRICANE SANDY OFF THE SOUTH CAROLINA
COASTLINE. WITHIN THE TROUGHING...MAIN SHORTWAVES OF NOTE ARE ONE
CROSSING THE FORECAST AREA AND THE OTHER AT THE BASE OF THE TROUGH
IN ARKANSAS. THE SHORTWAVE CROSSING THE FORECAST AREA HAS BEEN
PRODUCING SCATTERED CIRRUS CLOUD COVER...WITH DRY AIR ON 00Z
SOUNDINGS FROM MPX AND GRB PREVENTING ANY OTHER CLOUDS. TO THE WEST
OF THE SHORTWAVE...A COLLECTION OF LOW TO MID CLOUDS ARE PRESENT
OVER THE EASTERN DAKOTAS AND WESTERN MINNESOTA...ASSOCIATED WITH
ISENTROPIC LIFT SITUATED AROUND 285K. AIRMASS REMAINS COOL UNDER THE
UPPER TROUGHING WITH 00Z SOUNDINGS AT MPX...GRB AND DVN ALL NEAR
-7C. AT THE SURFACE...A RIDGE OF HIGH PRESSURE ENCOMPASSES MUCH OF
THE UPPER MISSISSIPPI RIVER VALLEY REGION AND SOUTH INTO THE KANSAS
CITY AREA.
TODAY THROUGH MONDAY...THE WEATHER PATTERN OVER THE FORECAST AREA
WILL GET BLOCKED UP...DUE TO:
1. RIDGING NEAR THE WEST COAST MOVING INTO MUCH OF THE WESTERN U.S.
2. HURRICANE SANDY PHASING AND STRENGTHENING NEAR NEW JERSEY WITH
THE UPPER TROUGHING CURRENTLY IN MISSOURI AND ARKANSAS.
AS A RESULT...THE SURFACE HIGH PRESSURE RIDGE OVER THE AREA WILL GO
NOWHERE. IN ADDITION...THE LOW TO MID-LEVEL DRY AIR SEEN ON 00Z
SOUNDINGS WILL GO NOWHERE TOO...PREVENTING PRECIPITATION. NOTE...
THERE MAY BE SOME MID CLOUDS TRYING TO ENTER WESTERN SECTIONS OF THE
FORECAST AREA ON MONDAY...BUT THESE LOOK TO THIN AS THEY RUN INTO
SUBSIDENCE AND BLOCKING PRODUCED ON THE WEST SIDE OF SANDY. A FEW
MID CLOUDS MAY ENTER WESTERN SECTIONS OF THE FORECAST AREA THIS
MORNING...BUT THESE LOOK TO DISSIPATE THIS AFTERNOON AS THE
ISENTROPIC LIFT AIDING THEM SHIFTS OFF TO THE NORTH. 500MB HEIGHTS
ARE FORECAST TO RISE DURING THE NEXT 48 HOURS WHICH SHOULD HELP TO
GET A LITTLE WARMER AIR INTO THE AREA. 850MB TEMPS REFLECT THIS BY
CLIMBING TO -4 TO -6C AT 18Z TODAY AND TO -1 TO -4C AT 18Z MONDAY.
THUS...HIGHS SHOULD WARM A FEW DEGREES EACH DAY...TOPPING OUT IN THE
MID 40S TODAY AND MID TO UPPER 40S ON MONDAY. LOWS TONIGHT HAVE THE
POTENTIAL TO BE QUITE COOL GIVEN MOSTLY CLEAR SKIES...LIGHT WINDS
AND DRY AIR IN PLACE. THUS...STAYED ON THE COOL SIDE OF
GUIDANCE...ESPECIALLY FOR THE TYPICAL COLD SPOTS IN WISCONSIN.
MONDAY NIGHT THROUGH TUESDAY NIGHT...THE FIGHT LOOKS TO CONTINUE
BETWEEN THE UPPER RIDGING OVER THE WESTERN U.S. TRYING TO PUSH
EASTWARD...BUT KEEPS RUNNING INTO DEEP CLOSED OFF UPPER TROUGHING
OVER THE EASTERN U.S. CONTAINING THE EXTRATROPICAL STATE OF SANDY.
THUS...THE SURFACE RIDGE OVER THE AREA THROUGH MONDAY STILL LOOKS TO
REMAIN OVERHEAD OR NEARBY. THERE ARE SUGGESTIONS THAT THE RIDGE
COULD RETROGRADE WEST SLIGHTLY...DEPENDING ON THE EXACT EVOLUTION OF
SANDY...RESULTING IN AN INCREASE OF NORTHERLY WINDS OVER EASTERN
PORTIONS OF THE FORECAST AREA ON TUESDAY. AGAIN WITH THE BLOCKING IN
PLACE...NOT ANTICIPATING ANY PRECIPITATION. CLOUD COVER LOOKS
LIMITED TOO...WITH JUST SOME PERIODS OF MID OR HIGH CLOUDS CROSSING
WESTERN PORTIONS OF THE FORECAST AREA. DUE TO THE BLOCKED UP
PATTERN...850MB TEMPS CONTINUE TO RISE JUST SLOWLY...CLIMBING TO +1
TO -2C AT 18Z TUESDAY. THEREFORE...HIGHS ON TUESDAY WILL ONLY END UP
A COUPLE DEGREES AT MOST WARMER THAN MONDAY. LOWS ON THE OTHER HAND
HAVE THE POTENTIAL TO BE QUITE COOL BOTH NIGHTS...AGAIN DUE TO LIGHT
WINDS AND DRY AIR. LOCATIONS WEST OF THE MISSISSIPPI RIVER SHOULD
HAVE SOME PASSING CLOUDS TO LIMIT THE COOLING. IN GENERAL...STAYED
NEAR GUIDANCE FOR LOWS WEST OF THE MISSISSIPPI RIVER AND TOWARDS THE
COLD SIDE OF GUIDANCE EAST OF THE MISSISSIPPI RIVER.
.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT
222 AM CDT SUN OCT 28 2012
28.00Z ECMWF/CANADIAN/GFS AND GFS ENSEMBLES HAVE THE SAME GENERAL
THEME THROUGH THE LONG TERM PERIOD ON THE UPPER LEVEL PATTERN...BUT
THERE ARE MAJOR TIMING ISSUES. MUCH OF THE PROBLEM IN THE LONG TERM
PERIOD IS HOW AND WHEN THE DEEP EASTERN U.S. TROUGHING AND
EXTRATROPICAL SANDY LIFTS OUT. ALL MODELS KEEP STRONG RIDGING IN THE
DAVIS STRAIGHT AREA INTO THE WEEKEND...SO ANY EJECTION OF THAT DEEP
EASTERN U.S. TROUGHING SHOULD BE SLOW TO OCCUR. AT THE SAME TIME
THERE IS SUBTROPICAL RIDGING OVER THE WESTERN U.S. GETTING PUSHED
EASTWARD BY TROUGHING COMING INTO CALIFORNIA OFF THE PACIFIC. IT IS
THIS TROUGH WHICH WE HAVE TO WATCH FOR POTENTIAL PRECIPITATION
TOWARDS THE WEEKEND. MODELS DIFFER GREATLY ON HOW FAR EAST THAT
TROUGHING MAKES IT...WITH THE 28.00Z GFS MUCH MORE AGGRESSIVE THAN
THE 27.12Z/28.00Z ECMWF...SUGGESTING IT LIFTS INTO OUR AREA FOR THE
WEEKEND. FOR NOW...HAVE STAYED TOWARDS THE ECMWF WHICH HAS SUPPORT
FROM SOME OF THE GFS ENSEMBLE MEMBERS.
IN SUMMARY...THE AREA LOOKS TO STAY DRY WITH HIGH PRESSURE MOSTLY
DOMINATING AT THE SURFACE. FOR THE WEEKEND...THERE MAY BE A CHANCE
OF HAVING SOME WARM ADVECTION PRECIPITATION...BUT THE SIGNAL IS VERY
WEAK AND MOSTLY SOUTH OF THE AREA. THUS...A DRY FORECAST CONTINUES.
TEMPERATURES SHOULD CONTINUE TO GRADUALLY WARM DUE TO BOTH AIRMASS
MODIFICATION AND THEN WARM ADVECTION TOWARDS THE WEEKEND. NOTE THAT
THERE IS POTENTIAL FOR A COLD FRONT TO COME THROUGH THE AREA ON
SATURDAY FROM THE NORTHWEST...AS INDICATED IN THE 27.12Z/28.00Z
ECMWF. THIS FRONT COULD DEFLECT SOME OF THE WARMER AIR TRYING TO
COME UP INTO THE AREA ON FRIDAY. FOLLOWED THE CONSENSUS FOR
TEMPERATURES WHICH BRINGS HIGHS BACK TO NEAR NORMAL BY THURSDAY THEN
HOLDS THEM STEADY INTO THE WEEKEND.
&&
.AVIATION...THROUGH 06Z MONDAY
1142 PM CDT SAT OCT 27 2012
VFR CONDITIONS TO CONTINUE AT LSE/RST THROUGH SUNDAY NIGHT AS A
RIDGE OF HIGH PRESSURE REMAINS PARKED OVER THE REGION. WINDS WILL
BE LIGHT THROUGHOUT THE PERIOD AS THE RIDGE AXIS SLOWLY TRACKS TO
THE EAST ON SUNDAY. BROKEN HIGH LEVEL CLOUD COVER WILL ALSO
PERSIST OVERNIGHT WITH SOME MID LEVEL 4-6KFT CIGS POSSIBLE SUNDAY
AS A STORM SYSTEM DISSOLVES AS IT RUNS INTO THE DRY RIDGE ALREADY
IN PLACE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
222 AM CDT SUN OCT 28 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
727 AM EDT SUN OCT 28 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 446 AM EDT SUN OCT 28 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF EXTENDING FROM
MANITOBA S THRU THE MISSISSIPPI VALLEY. MINOR SHORTWAVE AND
ASSOCIATED INVERTED SFC TROF ACROSS SD INTO NRN MN IS AIDING AN
AREA OF SNOW OVER NRN MN. OTHERWISE...IT`S A QUIET NIGHT WEATHER
WISE ACROSS THE UPPER GREAT LAKES. SFC HIGH PRES IS COVERING THE
AREA FROM SRN SASKATCHEWAN/MANITOBA INTO THE UPPER GREAT LAKES...
RESULTING IN LIGHT/CALM WIND ACROSS UPPER MI EARLY THIS MORNING.
WITH 850MB TEMPS AROUND -9C...OVERWATER INSTABILITY IS SUFFICIENT
FOR LES...BUT SFC BASED WELL-MIXED LAYER EVIDENT ON UPSTREAM 00Z
KINL SOUNDING IS A BIG NEGATIVE. AS A RESULT...KMQT RADAR HAS ONLY
HINTED AT SOME SPRINKLES/FLURRIES OVER ERN LAKE SUPERIOR INTO NE
UPPER MI DURING THE OVERNIGHT. NOTHING MORE THAN SOME HIGH CLOUDS
ACROSS PORTIONS OF THE W AND CNTRL FCST AREA HAS ALLOWED TEMPS TO
PLUMMET INTO THE UPPER TEENS IN SOME OF THE TRADITIONAL COLD SPOTS.
QUIET WEATHER WILL BE THE RULE IN THE SHORT TERM HAS SFC HIGH PRES
DOMINATES THE AREA. THE AREA OF SNOW IN NRN MN WILL WEAKEN AND LIFT
NE TODAY...PASSING W OF THE FCST AREA. MEANWHILE...IF THERE ARE ANY
SPRINKLES/FLURRIES MOVING ONSHORE TO THE E OF MARQUETTE...THOSE WILL
DISSIPATE BY AFTN AS AIRMASS MODIFIES SLIGHTLY. IN THE END...EXPECT
A MIX OF CLOUDS AND SUN WITH TEMPERATURES RISING TO 40-45...WARMEST
SCNTRL.
WITH ANOTHER NIGHT OF LIGHT/CALM WIND...FAVORED THE LOWER SIDE OF
GUIDANCE TONIGHT FOR MINS. TEMPS SHOULD FALL BACK TO THE MID/UPPER
TEENS IN THE TRADITIONAL COLDS SPOTS OVER THE W HALF INTERIOR.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 446 AM EDT SUN OCT 28 2012
MAIN SHOW FOR THE LONG TERM IS WITH REMNANTS OF HURRICANE SANDY
MOVING INTO THE CWA TUE AND WED...WITH LITTLE TO NO SIGNIFICANT
CHANGES TO FORECAST THINKING FROM THE LAST COUPLE OF SHIFTS.
STARTING WITH MON...THINGS LOOKS PRETTY QUIET OVER THE CWA AS A SFC
RIDGE SITS OVER UPPER MI. NO SIGNIFICANT PRECIP IS EXPECTED MON AND
MON NIGHT.
SANDY MAKES LANDFALL LATE MON INTO MON NIGHT OVER OR NEAR NJ...THE
SYSTEM THEN SPINS OVER SE PA THROUGH 06Z WED BEFORE SHIPPING N TO
FAR SRN QUEBEC BY 12Z THU. MOISTURE WILL WRAP AROUND THE SYSTEM AS
THE SYSTEM PUSHES THE SFC RIDGE AXIS FROM OVER THE CWA TO JUST NW OF
THE CWA. BEING BETWEEN THE LOW AND THE RIDGE WILL KEEP WINDS
GENERALLY NLY/NELY TUE AND WED AS THE PRESSURE GRADIENT INCREASES.
THE TRICKIEST PART OF THE FORECAST WITH THIS SYSTEM WILL BE THE
PRECIP CUT OFF OVER THE W CLOSER TO THE SFC RIDGE AND AN UPPER
RIDGE...AND PRECIP TYPE AS MODELS SHOW A RIBBON OF COLDER AIR OVER
THE CENTRAL CWA THAT WOULD BE SUPPORTIVE OF SNOW. WILL FOCUS IN A
BIT MORE ON THESE DETAILS.
FOR PRECIP CHANCES...DEEP MOISTURE WILL FIRST ROTATE INTO THE CWA
FROM E TO W AROUND 12Z TUE AND WILL REACH PEAK DEPTH INTO THE CWA
WED EVENING. QUESTION IS HOW FAR W WILL THE MOISTURE GO. ALL MODELS
SHOW A SHARP CUT OFF FROM NEAR 100 PERCENT 1000-700MB RH EAST TO
LESS THAN 20 PERCENT RH WEST. THE 00Z/28 GFS IS THE FARTHEST W WITH
THE CUT OFF...BRINGING HIGHER RH VALUES OVER ALL OF THE CWA...WHILE
THE 12Z/27 ECMWF IS ON THE E SIDE OF GUIDANCE WITH THE TRANSITION
FROM MOIST TO DRY OVER THE CENTRAL CWA. THE 00Z/28 NAM IS MORE IN
BETWEEN THE GFS AND ECMWF WITH THE CUT OFF CLOSER TO THE ECMWF THAN
THE GFS. LIKE THE PREVIOUS FORECAST POPS THAT COVER WRN UPPER MI IN
SLIGHT CHANCE POPS AND HAVE LIKELY POPS OVER NCENTRAL AND ERN UPPER
MI. GIVEN THE GOOD MOISTURE OVER AT LEAST THE ERN HALF OF THE
CWA...STRONG CYCLONIC NNELY FLOW /AND RESULTING UPSLOPE FLOW IN
HIGHER TERRAIN AREAS/ AND COOL 900-850MB TEMPS THAT WILL RESULT IN
DELTA T VALUES AROUND 7-10C THESE LIKELY POPS ARE CERTAINLY
JUSTIFIED...AND WILL INCREASE THESE SOME.
BEST CHANCES FOR MIXED PRECIP WILL BE TUE NIGHT AS NEAR SFC TEMPS
COOL INTO THE LOW TO MID 30S UNDER THE SUB-FREEZING LAYERS ABOVE
OVER THE NCENTRAL CWA. OVER THE E...WARMER AIR WILL WRAP AROUND THE
SYSTEM AT AROUND 800MB...AND SHOULD BE DEEP AND WARM ENOUGH TO KEEP
MOST PRECIP RAIN. HOWEVER...OVER THE ERN CWA...SOME OF THE PRECIP
COULD FALL AS SLEET BEFORE THE DEEPER WARM AIR ARRIVES SINCE 900MB
TEMPS WILL BE AROUND -3C. BACK TO THE NCENTRAL...ESPECIALLY THE
HIGHER TERRAIN...IT APPEARS PRECIP WILL LIKELY BE ALL SNOW TUE NIGHT
INTO EARLY WED. AGREE THAT BEST BET FOR SNOWFALL AMOUNTS LOOKS TO BE
ON THE LOW SIDE IN THE 1-3 INCH RANGE GIVEN THAT THE SNOW GROWTH
ZONE WILL BE AT 550-500MB AND OUT OF THE BEST LIFT FROM UPSLOPE/LAKE
ENHANCEMENT AND THAT SFC TEMPS WILL BE NEAR OR ABOVE FREEZING.
STILL...THERE IS POTENTIAL FOR INCREASED SNOWFALL AMOUNTS IF ALL
FACTORS LINE UP. THIS WOULD LIKELY CAUSE SOME SLOPPY DRIVING
CONDITIONS FOR THE WED MORNING COMMUTE SO WILL KEEP MENTION IN THE
HWO.
WINDS WILL BE ANOTHER IMPORTANT ASPECT WITH THIS SYSTEM. 925MB WINDS
GREATER THAN 30KTS MOVES IN FROM E TO W LATE MON INTO MON
NIGHT...WITH 925MB WINDS OF 40-45KTS OVER ERN UPPER MI FROM AROUND
09Z TUE TO AROUND 06Z WED. THESE HIGHER WINDS SHOULD HAVE A BETTER
CHANCE AT MIXING TO THE SFC OVER LAND DURING THE DAY ON TUE BUT
EXPECT MOST GUSTS TO BE 40MPH OR LESS...WITH POTENTIAL FOR SOME
50MPH GUSTS. OVER LAKE SUPERIOR AND NW LAKE MI...EXPECT GUSTS TO
REMAIN BELOW 40KTS SINCE WE WILL SEE WARM ADVECTION AND THE SYSTEM
WILL BE WEAKENING...NOT THE TYPICAL SIGNAL FOR STRONG LAKE WINDS.
ECMWF MOVES THE PRECIP OUT BY LATE WED NIGHT WHILE THE GFS KEEP
PRECIP INTO EARLY THU AFTERNOON. WILL GO CLOSER TO THE PREVIOUS
FORECAST AND THE ECMWF FOR POPS ON THU.
UNCERTAINTY INCREASES FOR FRI AND SAT...AND WITH HIGHER IMPACT
EARLIER IN THE WEEK...JUST USED CONSENSUS OF MODELS FOR THE LATER
PERIODS OF THE FORECAST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 725 AM EDT SUN OCT 28 2012
WITH HIGH PRES RIDGE OVER THE AREA AND RELATIVELY DRY LOW-LEVELS
THRU THIS FCST PERIOD...EXPECT VFR CONDITIONS AND LIGHT WINDS AT
KIWD/KCMX/KSAW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 446 AM EDT SUN OCT 28 2012
HIGH PRES RIDGE EXTENDING S THRU CNTRL LAKE SUPERIOR TODAY/TONIGHT
AND THEN DRIFTING W TO WRN LAKE SUPERIOR MON WILL LEAD TO LIGHT
WINDS UNDER 20KT. PRES GRADIENT WILL TIGHTEN A BIT OVER THE FAR E
MON...SO WINDS THERE SHOULD RISE UP TO 15-25KT. MON NIGHT THRU
THU...THE HIGH PRES RIDGE WILL DRIFT A LITTLE FARTHER W.
MEANWHILE...POWERFUL LOW PRESSURE MOVING ONSHORE OVER THE MID
ATLANTIC STATES MONDAY NIGHT WILL WEAKEN AS IT MOVES TO THE LOWER
GREAT LAKES LATE WEDNESDAY AND INTO SOUTHERN QUEBEC THURSDAY.
ALTHOUGH WEAKENING...TIGHTENING PRES GRADIENT AND EXPANDING WIND
FIELD AROUND STORM SYSTEM WILL LIKELY LEAD TO NORTHERLY GALES OVER
ROUGHLY THE E HALF OF LAKE SUPERIOR MON NIGHT THRU EARLY WED. A FEW
FACTORS WILL KEEP WINDS IN CHECK. FIRST...SYSTEM WILL BE WEAKENING
QUICKLY AFTER IT MOVES ONSHORE OVER THE MID ATLANTIC STATES.
SECOND...THERE ARE NO STRONG DYNAMICS AFFECTING THE UPPER GREAT
LAKES...AND THIRD THERE IS NO CAA. SO...PROBABLY WON`T SEE GALES
OVER 35-40KT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM MONDAY EVENING THROUGH WEDNESDAY MORNING FOR
LSZ251-267.
GALE WATCH FROM LATE MONDAY NIGHT THROUGH WEDNESDAY MORNING FOR
LSZ249-250-266.
LAKE MICHIGAN...
GALE WATCH FROM MONDAY EVENING THROUGH WEDNESDAY MORNING FOR
LMZ221-248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
923 AM EDT SUN OCT 28 2012
.SYNOPSIS...
HURRICANE SANDY WILL MOVE ONSHORE OVER NEW JERSEY ON MONDAY NIGHT
AND THEN TRACK ACROSS CENTRAL PENNSYLVANIA TO NEW YORK TUESDAY AND
WEDNESDAY. THIS LARGE STORM WILL DOMINATE THE WEATHER ACROSS
NORTHERN OHIO AND NORTHWEST PENNSYLVANIA FOR MUCH OF THE COMING
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CONTINUING WITH THEME OF PREVIOUS UPDATE...WILL ENHANCE POPS MORE
FURTHER TO THE WEST AS BEST ENHANCED BAND HAS SET UP FROM NEAR
MADISON SW TO NEAR MT VERNON AND IS MAKING STEADY PROGRESS TO THE
NW. BOTH RUC AND HRRR SEEM TO BE ON TOP OF THIS SO WILL GENERALLY
USE AVERAGE OF THEIR QPF FIELDS TO DETERMINE POPS FOR REST OF TODAY.
SOME SMALL BREAKS IN CLOUDS OVER WEST THIRD OF THE AREA BUT SHOULD
FILL BACK IN FROM EAST TO WEST. TEMPS NOT LIKELY TO RISE MUCH FOR
EAT HALF OF THE AREA SO WILL ADJUST DOWN A LITTLE THERE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
SHORT TERM PERIOD WILL BE QUITE ACTIVE WITH THE REMNANTS OF SANDY
MOVING THROUGH PA INTO NEW YORK MONDAY NIGHT THROUGH WEDNESDAY
ALTHOUGH BY WEDNESDAY THE WIND FIELD WEAKENS CONSIDERABLY.
FOLLOWED THE NAM12 THROUGH MUCH OF THE SHORT TERM PERIOD. TO BE
BRIEF...POPS WILL BE CATEGORICAL FOR MOST OF THE SHORT TERM PERIOD
ACROSS THE EASTERN TWO THIRDS OF THE AREA. THE WESTERN THIRD WILL
BE CLOSER TO THE DRY AIR AND WILL WAVER BETWEEN SLIGHT CHANCE AND
LIKELY DEPENDING ON MOISTURE DEPTH ON THE NAM. BIG PROBLEM WILL BE
OF COURSE THE WIND AND FLOOD POTENTIAL WITH THE STORM. WILL
CONTINUE WITH THE HIGH WIND WATCH AS GUIDANCE CONTINUES TO SUPPORT
WINDS OF 30 TO 30 MPH WITH GUSTS TO /OVER 50 KNOTS. AREA WHERE NO
HIGH WIND WATCH IS IN EFFECT COULD STILL SEE WIND ADVISORY
CRITERIA SO WILL NEED TO CONTINUE TO MONITOR FOR THE POSSIBILITY.
BASED ON NUMERICAL GUIDANCE...HIGHEST WIND TIMING WOULD BE MONDAY
NIGHT THROUGH TUESDAY MID/LATE AFTERNOON. ALSO CONTINUE TO LIKE THE
FLOOD WATCH PLACEMENT. 5 DAY FORECAST FROM HPC IS 3 TO 4+ INCHES
ACROSS NORTHEAST OHIO AND NWRN PA. SIMILAR TO THE WIND
TIMING...BEST POTENTIAL FOR HEAVY RAIN WILL COME MONDAY NIGHT AND
POSSIBLY INTO EARLY TUESDAY. ALSO GIVEN THE WAVES EXPECTED ON LAKE
ERIE COMBINED WITH THE FACT THAT WINDS WILL BE FROM THE NORTH FOR
A GOOD PORTION OF THE STORM...WILL ISSUE A LAKESHORE FLOOD WATCH.
HIGH TEMPS IN THE 40S TO NEAR 50. LOWS IN THE 30S. JUST AN ASIDE
HERE...850MB TEMPS DO DROP TO -3C OR SO ACROSS THE WESTERN
COUNTIES LATE SUNDAY NIGHT AND AGAIN MONDAY NIGHT BUT
REALLY...THIS TIME OF YEAR...WOULD PREFER LOWER 850MB TEMPS BEFORE
FORECASTING SNOW. SO FOR NOW WILL KEEP PRECIP ALL RAIN.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
BEGINNING THURSDAY...THE REMNANT LOW FROM SANDY WILL BEGIN MOVING
AWAY TO THE NORTHEAST...BUT CYCLONIC FLOW WITH TROUGH STILL OVER THE
AREA WILL ALLOW FOR CLOUDS AND SCATTERED SHOWERS...BEST CHANCE
ACROSS NE OH/NW PA...TO CONTINUE. KEPT LIKELY POPS ACROSS THE
NORTHEAST WITH CHC TRENDING BACK TO THE SOUTH AND WEST. LOOKS LIKE
FRIDAY WILL BEGIN THE TRANSITION LOSING THE INFLUENCE OF THE LOW AND
UPPER TROUGH WITH RIDGING ALOFT BUILDING IN. DIDN/T WANT TO GET TOO
SPECIFIC GIVEN HOW FAR OUT...BUT THINKING POPS MENTIONED IN THE
FORECAST FOR FRIDAY...ESPECIALLY ACROSS THE EAST MAY BE MORE DURING
THE MORNING WITH IMPROVING IN THE AFTERNOON. CLOUDS BUILD BACK INTO
THE AREA FRIDAY NIGHT WITH A WARM FRONT MOVING ACROSS THE AREA. WENT
WITH DRY CONDITIONS FOR SAT AT THIS POINT...BUT LOOKS LIKE PRECIP
WILL BE QUICKLY BUILDING TOWARD THE AREA LATE IN THE DAY. OVERALL
MADE ADJUSTMENTS TO PREVIOUS FORECAST TEMPS COMPARED TO MEX GUIDANCE.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
WATER VAPOR SHOWING UPPER TROUGH SWINGING NORTHEAST TOWARD THE
OHIO VALLEY THIS MORNING WITH RAIN QUICKLY DEVELOPING ACROSS
EASTERN OHIO AND SLOWLY BACK WESTWARD. EXPECTING A SLOW WESTWARD
PUSH WITH THE RAIN GOING THROUGH THE MORNING AND AFTERNOON WITH
INTENSIFYING RAIN ACROSS THE EAST. ATTEMPTED SOME TIMING TO BRING
RAIN INTO CLE AND MFD...WITH RAIN AT ERI YNG AND CAK EXPECTED TO
BE ONGOING FOR MUCH OF TODAY. WESTERN SITES MAY NOT SEE ANY RAIN
AT ALL THROUGH TODAY BUT THINKING THEY MAY HOLD ONTO CIGS JUST
INTO VFR CATEGORY.
FOR ALL EXCEPT THE WESTERN SITES MVFR AND PERIODS OF IFR WILL
PERSIST. WINDS WILL ALSO BE GUSTY TODAY FROM THE NORTH. SUSTAINED
WINDS 14-20KT WITH GUSTS TO 30KT POSSIBLE. HIGHEST VALUES MAINLY
AT CLE AND ERI.
.OUTLOOK...NON-VFR NRN OH/NW PA MONDAY. NON-VFR MOST AREAS
TUESDAY AND WEDNESDAY.
&&
.MARINE...
NORTHERLY WINDS ARE EXPECTED TO GRADUALLY INCREASE TOWARD 30 KNOTS
BY LATE TODAY. WINDY CONDITIONS WITH HIGH WAVES WILL CONTINUE
THROUGH THE FORECAST PERIOD. NO CHANGES TO HEADLINES WITH THIS
FORECAST ISSUANCE WITH MODELS CONTINUING TO SHOW THE POSSIBILITY FOR
STORM FORCE WINDS ON THE LAKE MONDAY NIGHT THROUGH EARLY TUESDAY
AFTERNOON. OVERALL MADE ONLY SMALL ADJUSTMENTS TO WINDS...BUT NEW
GUIDANCE CONSISTENT WITH PREVIOUS FORECAST AND SEE LITTLE REASON TO
ADJUST IN EITHER DIRECTION. WAVES WILL BE SIGNIFICANT ACROSS THE
LAKE FROM LATE MONDAY THROUGH MIDDAY TUESDAY...WITH 18 FEET A STRONG
POSSIBILITY. WINDS ARE EXPECTED TO SUBSIDE BELOW GALE FORCE THROUGH
TUESDAY NIGHT AND EARLY WEDNESDAY WHILE SHIFTING TO THE NORTHWEST.
WINDS WILL TURN TO THE WEST THROUGH WEDNESDAY. SMALL CRAFT
CONDITIONS ARE EXPECTED TO DIMINISH FROM WEST TO EAST ON FRIDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...FLOOD WATCH FROM LATE TONIGHT THROUGH TUESDAY EVENING FOR
OHZ010>014-020>023-031>033-038-089.
LAKESHORE FLOOD WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY
EVENING FOR OHZ003-007>012-089.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING
FOR OHZ009>014-019>023-029>033-038-089.
PA...FLOOD WATCH FROM LATE TONIGHT THROUGH TUESDAY EVENING FOR
PAZ001>003.
LAKESHORE FLOOD WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY
EVENING FOR PAZ001.
HIGH WIND WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING
FOR PAZ001>003.
MARINE...STORM WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING FOR
LEZ061-142>149-162>169.
SMALL CRAFT ADVISORY UNTIL NOON EDT MONDAY FOR LEZ142>149.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK/ADAMS
SHORT TERM...TK
LONG TERM...ABE
AVIATION...ABE
MARINE...ABE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
556 AM CDT SUN OCT 28 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
222 AM CDT SUN OCT 28 2012
MAIN FORECAST CONCERNS REMAIN ON CLOUDS AND TEMPERATURES WITH THE
BLOCKED WEATHER PATTERN IN PLACE.
CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING ALONG THE WEST COAST OF THE U.S....TROUGHING FROM
MANITOBA SOUTH THROUGH THE FORECAST AREA AND INTO ARKANSAS...STRONG
RIDGING OVER NEWFOUNDLAND AND HURRICANE SANDY OFF THE SOUTH CAROLINA
COASTLINE. WITHIN THE TROUGHING...MAIN SHORTWAVES OF NOTE ARE ONE
CROSSING THE FORECAST AREA AND THE OTHER AT THE BASE OF THE TROUGH
IN ARKANSAS. THE SHORTWAVE CROSSING THE FORECAST AREA HAS BEEN
PRODUCING SCATTERED CIRRUS CLOUD COVER...WITH DRY AIR ON 00Z
SOUNDINGS FROM MPX AND GRB PREVENTING ANY OTHER CLOUDS. TO THE WEST
OF THE SHORTWAVE...A COLLECTION OF LOW TO MID CLOUDS ARE PRESENT
OVER THE EASTERN DAKOTAS AND WESTERN MINNESOTA...ASSOCIATED WITH
ISENTROPIC LIFT SITUATED AROUND 285K. AIRMASS REMAINS COOL UNDER THE
UPPER TROUGHING WITH 00Z SOUNDINGS AT MPX...GRB AND DVN ALL NEAR
-7C. AT THE SURFACE...A RIDGE OF HIGH PRESSURE ENCOMPASSES MUCH OF
THE UPPER MISSISSIPPI RIVER VALLEY REGION AND SOUTH INTO THE KANSAS
CITY AREA.
TODAY THROUGH MONDAY...THE WEATHER PATTERN OVER THE FORECAST AREA
WILL GET BLOCKED UP...DUE TO:
1. RIDGING NEAR THE WEST COAST MOVING INTO MUCH OF THE WESTERN U.S.
2. HURRICANE SANDY PHASING AND STRENGTHENING NEAR NEW JERSEY WITH
THE UPPER TROUGHING CURRENTLY IN MISSOURI AND ARKANSAS.
AS A RESULT...THE SURFACE HIGH PRESSURE RIDGE OVER THE AREA WILL GO
NOWHERE. IN ADDITION...THE LOW TO MID-LEVEL DRY AIR SEEN ON 00Z
SOUNDINGS WILL GO NOWHERE TOO...PREVENTING PRECIPITATION. NOTE...
THERE MAY BE SOME MID CLOUDS TRYING TO ENTER WESTERN SECTIONS OF THE
FORECAST AREA ON MONDAY...BUT THESE LOOK TO THIN AS THEY RUN INTO
SUBSIDENCE AND BLOCKING PRODUCED ON THE WEST SIDE OF SANDY. A FEW
MID CLOUDS MAY ENTER WESTERN SECTIONS OF THE FORECAST AREA THIS
MORNING...BUT THESE LOOK TO DISSIPATE THIS AFTERNOON AS THE
ISENTROPIC LIFT AIDING THEM SHIFTS OFF TO THE NORTH. 500MB HEIGHTS
ARE FORECAST TO RISE DURING THE NEXT 48 HOURS WHICH SHOULD HELP TO
GET A LITTLE WARMER AIR INTO THE AREA. 850MB TEMPS REFLECT THIS BY
CLIMBING TO -4 TO -6C AT 18Z TODAY AND TO -1 TO -4C AT 18Z MONDAY.
THUS...HIGHS SHOULD WARM A FEW DEGREES EACH DAY...TOPPING OUT IN THE
MID 40S TODAY AND MID TO UPPER 40S ON MONDAY. LOWS TONIGHT HAVE THE
POTENTIAL TO BE QUITE COOL GIVEN MOSTLY CLEAR SKIES...LIGHT WINDS
AND DRY AIR IN PLACE. THUS...STAYED ON THE COOL SIDE OF
GUIDANCE...ESPECIALLY FOR THE TYPICAL COLD SPOTS IN WISCONSIN.
MONDAY NIGHT THROUGH TUESDAY NIGHT...THE FIGHT LOOKS TO CONTINUE
BETWEEN THE UPPER RIDGING OVER THE WESTERN U.S. TRYING TO PUSH
EASTWARD...BUT KEEPS RUNNING INTO DEEP CLOSED OFF UPPER TROUGHING
OVER THE EASTERN U.S. CONTAINING THE EXTRATROPICAL STATE OF SANDY.
THUS...THE SURFACE RIDGE OVER THE AREA THROUGH MONDAY STILL LOOKS TO
REMAIN OVERHEAD OR NEARBY. THERE ARE SUGGESTIONS THAT THE RIDGE
COULD RETROGRADE WEST SLIGHTLY...DEPENDING ON THE EXACT EVOLUTION OF
SANDY...RESULTING IN AN INCREASE OF NORTHERLY WINDS OVER EASTERN
PORTIONS OF THE FORECAST AREA ON TUESDAY. AGAIN WITH THE BLOCKING IN
PLACE...NOT ANTICIPATING ANY PRECIPITATION. CLOUD COVER LOOKS
LIMITED TOO...WITH JUST SOME PERIODS OF MID OR HIGH CLOUDS CROSSING
WESTERN PORTIONS OF THE FORECAST AREA. DUE TO THE BLOCKED UP
PATTERN...850MB TEMPS CONTINUE TO RISE JUST SLOWLY...CLIMBING TO +1
TO -2C AT 18Z TUESDAY. THEREFORE...HIGHS ON TUESDAY WILL ONLY END UP
A COUPLE DEGREES AT MOST WARMER THAN MONDAY. LOWS ON THE OTHER HAND
HAVE THE POTENTIAL TO BE QUITE COOL BOTH NIGHTS...AGAIN DUE TO LIGHT
WINDS AND DRY AIR. LOCATIONS WEST OF THE MISSISSIPPI RIVER SHOULD
HAVE SOME PASSING CLOUDS TO LIMIT THE COOLING. IN GENERAL...STAYED
NEAR GUIDANCE FOR LOWS WEST OF THE MISSISSIPPI RIVER AND TOWARDS THE
COLD SIDE OF GUIDANCE EAST OF THE MISSISSIPPI RIVER.
.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT
222 AM CDT SUN OCT 28 2012
28.00Z ECMWF/CANADIAN/GFS AND GFS ENSEMBLES HAVE THE SAME GENERAL
THEME THROUGH THE LONG TERM PERIOD ON THE UPPER LEVEL PATTERN...BUT
THERE ARE MAJOR TIMING ISSUES. MUCH OF THE PROBLEM IN THE LONG TERM
PERIOD IS HOW AND WHEN THE DEEP EASTERN U.S. TROUGHING AND
EXTRATROPICAL SANDY LIFTS OUT. ALL MODELS KEEP STRONG RIDGING IN THE
DAVIS STRAIGHT AREA INTO THE WEEKEND...SO ANY EJECTION OF THAT DEEP
EASTERN U.S. TROUGHING SHOULD BE SLOW TO OCCUR. AT THE SAME TIME
THERE IS SUBTROPICAL RIDGING OVER THE WESTERN U.S. GETTING PUSHED
EASTWARD BY TROUGHING COMING INTO CALIFORNIA OFF THE PACIFIC. IT IS
THIS TROUGH WHICH WE HAVE TO WATCH FOR POTENTIAL PRECIPITATION
TOWARDS THE WEEKEND. MODELS DIFFER GREATLY ON HOW FAR EAST THAT
TROUGHING MAKES IT...WITH THE 28.00Z GFS MUCH MORE AGGRESSIVE THAN
THE 27.12Z/28.00Z ECMWF...SUGGESTING IT LIFTS INTO OUR AREA FOR THE
WEEKEND. FOR NOW...HAVE STAYED TOWARDS THE ECMWF WHICH HAS SUPPORT
FROM SOME OF THE GFS ENSEMBLE MEMBERS.
IN SUMMARY...THE AREA LOOKS TO STAY DRY WITH HIGH PRESSURE MOSTLY
DOMINATING AT THE SURFACE. FOR THE WEEKEND...THERE MAY BE A CHANCE
OF HAVING SOME WARM ADVECTION PRECIPITATION...BUT THE SIGNAL IS VERY
WEAK AND MOSTLY SOUTH OF THE AREA. THUS...A DRY FORECAST CONTINUES.
TEMPERATURES SHOULD CONTINUE TO GRADUALLY WARM DUE TO BOTH AIRMASS
MODIFICATION AND THEN WARM ADVECTION TOWARDS THE WEEKEND. NOTE THAT
THERE IS POTENTIAL FOR A COLD FRONT TO COME THROUGH THE AREA ON
SATURDAY FROM THE NORTHWEST...AS INDICATED IN THE 27.12Z/28.00Z
ECMWF. THIS FRONT COULD DEFLECT SOME OF THE WARMER AIR TRYING TO
COME UP INTO THE AREA ON FRIDAY. FOLLOWED THE CONSENSUS FOR
TEMPERATURES WHICH BRINGS HIGHS BACK TO NEAR NORMAL BY THURSDAY THEN
HOLDS THEM STEADY INTO THE WEEKEND.
&&
.AVIATION...TODAY AND TONIGHT
556 AM CDT SUN OCT 28 2012
SCATTERED-BROKEN ALTOCUMULUS WITH BASES AOA 8KFT ASSOCIATED WITH A
WEAK MID-LEVEL TROUGH WILL BRUSH MAINLY KRST TODAY. THE TROUGH AND
CLOUDS WILL NORTH AWAY FROM THE AREA BY TONIGHT. A RIDGE OF HIGH
PRESSURE WILL THEN RE-ESTABLISH ITSELF OVER THE REGION THROUGH
MONDAY FOR CONTINUED QUIET/VFR CONDITIONS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
222 AM CDT SUN OCT 28 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
701 PM EDT SUN OCT 28 2012
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 332 PM EDT SUN OCT 28 2012
QUIET WEATHER UNDER HIGH PRESSURE RIDGE WILL GIVE WAY TO WINDY
CONDITIONS AND CHANCES FOR PRECIPITATION AS HURRICANE SANDY GETS
CLOSER. THE WINDIEST CONDITIONS CAN BE EXPECTED FROM MONDAY
EVENING THROUGH TUESDAY EVENING. CHANCES FOR RAIN WILL ARRIVE ON
TUESDAY AND REMAIN THROUGH WEDNESDAY WITH THE GREATEST CHANCES IN
THE NORTHEAST. THE WEATHER AFTER SANDY/S EXIT WILL BE DRY UNTIL
SATURDAY NIGHT WITH TEMPERATURES INCREASING TO NEAR NORMAL FOR THE
WEEKEND.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 622 PM EDT SUN OCT 28 2012
STRATOCU HAS BEEN STEADILY EXPANDING BACK WEST ACROSS CENTRAL
INDIANA FOR THE LAST FEW HOURS. NAM AND OP GFS GUIDANCE BOTH
CONTINUE TO BREAK UP THE LOWER CLOUDS ACROSS MUCH OF THE FORECAST
AREA TOWARDS MIDNIGHT AS SOME SUBSIDENCE DEVELOPS OVER THE REGION
WITH THE ONGOING CONSOLIDATION OF HURRICANE SANDY AND THE UPPER
LEVEL TROUGH OVER THE OHIO VALLEY. MOST RECENT RAP GUIDANCE HOWEVER
SUGGESTIVE THAT CLOUDS MAY LINGER BEYOND MIDNIGHT AND SATELLITE
TRENDS OVER THE LAST FEW HOURS WOULD TEND TO SUPPORT THAT IDEA AS
WELL. HAVE BUMPED UP CLOUD GRIDS EXTENSIVELY FOR THIS EVENING WITH
DECREASING CLOUDS THEREAFTER ALL BUT WESTERN PORTIONS OF THE
FORECAST AREA. WILL MONITOR CLOUD TRENDS OVER THE NEXT FEW HOURS AND
REVISIT POTENTIAL FOR ADDITIONAL CHANGES TO THE CLOUD FORECAST LATER
THIS EVENING.
REST UNCHANGED...PREVIOUS DISCUSSION FOLLOWS.
FORECAST FOCUS TONIGHT IS ON TEMPERATURES. COULD FLIRT WITH FREEZING
IN THE WEST WITH LESS CLOUD COVER THAN LAST NIGHT BUT THINK WINDS
STAYING UP WILL KEEP SIGNIFICANT DECOUPLING FROM OCCURRING AND KEEP
TEMPERATURES FROM FALLING TOO FAR. MORE CLOUDS EXPECTED IN THE EAST
WITH CLOUD BANDS ASSOCIATED WITH SANDY MAKING THEIR WAY HERE AND
HIGH PRESSURE STILL TO OUR WEST. WIND GUSTS OF THE AFTERNOON SHOULD
DROP OFF SUNSET BUT SUSTAINED WINDS SHOULD STAY UP AROUND 10 MPH OR
MORE OVERNIGHT WITH AN INCREASING PRESSURE GRADIENT.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
ISSUED AT 332 PM EDT SUN OCT 28 2012
FORECAST FOCUS IS ON WINDS MONDAY THROUGH TUESDAY AND POPS TUESDAY
THROUGH WEDNESDAY. AS SANDY TREKS NORTHWESTWARD AND GETS CLOSER TO
INDIANA WITH HIGH PRESSURE STILL ENTRENCHED OVER THE CENTRAL AND
WESTERN U.S. THE PRESSURE GRADIENT ACROSS THE AREA WILL TIGHTEN
CONSIDERABLY. GUIDANCE FROM THE MET IS SHOWING SUSTAINED WINDS OF
25-30 MPH ACROSS THE NORTHERN AND EASTERN COUNTIES. NAM SOUNDINGS
SHOW POTENTIAL FOR WIND GUSTS OF 40-50 MPH AS WELL. IN THE NAM THESE
BEGIN AROUND 18Z MONDAY...IN THE GFS AROUND 0Z TUESDAY. THE NAM
STARTS WEAKENING THE WINDS BY AS EARLY AS 18Z TUESDAY BUT THE GFS
DOESN/T BEGIN WEAKENING UNTIL AFTER 0Z WEDNESDAY AS THE NAM WEAKENS
SANDY FASTER THAN THE GFS OR THE ECMWF ONCE IT MAKES LANDFALL. SINCE
THE ECM IS ALSO FAVORING THE STRONGER SOLUTION WILL KEEP THE WINDS
UP THROUGH 0Z SIMILAR TO THE GFS BEFORE SLOWLY DECREASING THEM
TUESDAY NIGHT. THESE STRONGER WINDS ARE SHOWING UP ACROSS THE
NORTHEASTERN HALF TO TWO THIRDS OF CENTRAL INDIANA WHILE THE SOUTH
AND WEST WILL HAVE WINDS BUT NOT QUITE AS STRONG SINCE THEY ARE
FURTHER FROM THE LOW. THUS ISSUING A WIND ADVISORY FROM 21Z MONDAY
THROUGH 0Z WEDNESDAY FOR THE NORTHEASTERN HALF OR SO OF THE AREA.
MODELS ARE IN GOOD AGREEMENT ON KEEPING THE AREA DRY MONDAY AND MOST
OF MONDAY NIGHT. A LITTLE MOISTURE ARRIVES IN THE EASTERN COUNTIES
JUST PRIOR TO 12Z ON TUESDAY BUT ECMWF IS SLOWER WITH THIS. FORCING
IN NAM AND GFS LAGS THE MOISTURE SOME AND THUS THINK KEEPING DRY FOR
NOW PRIOR TO 12Z IS WAY TO GO. FROM TUESDAY THROUGH WEDNESDAY KEEP
POPS GOING WITH HIGHEST VALUES IN THE NORTHEAST CLOSEST TO SANDY AND
TAPERING TO DRY IN THE CENTRAL AND SOUTHWEST. BEST FORCING AND
CHANCE FOR PRECIP APPEARS TO BE IN NORTHEAST ON TUESDAY AND TUESDAY
NIGHT. LOWER CHANCES ON WEDNESDAY AS SANDY WEAKENS.
AS FAR AS TEMPERATURES ARE CONCERNED ALLBLEND CAPTURED 850 MB
TEMPERATURES AND SKY COVER TRENDS WELL WITH HIGHS IN THE MIDDLE 40S
TO LOWER 50S AND LOWS IN THE MIDDLE TO UPPER 30S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
ISSUED AT 224 PM EDT SUN OCT 28 2012
THE MAIN CHALLENGE TO THE LONG TERM WILL BE POPS FIRST WITH THE
REMNANTS OF SANDY WEDNESDAY NIGHT AND SECOND FROM A SOUTHERN SYSTEM
LATE IN THE WEEKEND.
THE 12Z GFS...GEFS AND 00Z ECMWF ARE MUCH CLOSER WITH THE CENTER OF
SURFACE LOW PRESSURE FROM THE REMNANTS OF SANDY THAN THE 12Z
CANADIAN AS IS PREFERRED. THE FORMER BLEND WHICH MATCHES UP WELL
WITH THE REGIONAL OUTPUT. THE BLEND HAS THE REMNANTS NEAR
SOUTHEASTERN ONTARIO AT 12Z THURSDAY WITH QPF ACROSS OUR FAR
NORTHEAST WEDNESDAY NIGHT WHICH LOOKS GOOD. SHOULD JUST BE RAIN
SHOWERS BASED ON MODEL SOUNDINGS. THEN...HIGH PRESSURE ACROSS THE
MISSISSIPPI VALLEY WILL FINALLY BE ABLE TO MOVE EAST ACROSS THE OHIO
VALLEY THROUGH THE FIRST HALF OF THE WEEKEND AS THE REMNANTS OF
SANDY LIFT NORTHEAST INTO NEW ENGLAND AND THE CANADIAN MARITIMES.
THE SECOND HALF OF THE WEEKEND WILL SEE TEMPERATURES WARM AGAIN TO
NEAR NORMAL WITH LITTLE CLOUD COVER AND SOUTHWEST FLOW AHEAD OF A
SOUTHERN SYSTEM THAT COULD BRING SOME MORE RAIN SHOWERS IN BY
SATURDAY NIGHT. FOR NOW...WITH THE UNCERTAINTY AND AFTER
COORDINATION...ONLY WENT WITH SLIGHT CHANCE POPS. REGIONAL OUTPUT
TEMPERATURES LOOK OK AND LEFT ALONE WITH AFTERNOON HIGHS WARMING TO
THE UPPER 50S NORTHEAST TO THE MID 60S SOUTHWEST AFTER STARTING OFF
ONLY IN THE UPPER 40S AND MID 50S THURSDAY.
&&
.AVIATION /DISCUSSION FOR THE 29/00Z TAFS/...
ISSUED AT 701 PM EDT SUN OCT 28 2012
VFR THROUGH THE PERIOD.
WINDS WILL BE THE MAJOR IMPACT DURING THIS TAF PERIOD AS THE
PRESSURE GRADIENT TIGHTENS SIGNIFICANTLY ACROSS THE AREA IN REPONSE
TO THE APPROACH OF HURRICANE SANDY TO THE EAST COAST. WINDS WILL
REMAIN UP OVERNIGHT TO AROUND 10KT...AND WILL STRENGTHEN FURTHER
TOMORROW WITH SUSTAINED WINDS PERHAPS PUSHING 20KT WITH GUSTS TO
30KT...AND PERHAPS EVEN SLIGHTLY HIGHER LATE IN THE PERIOD.
SKY COVER WILL GENERALLY CONSIST OF SCT-BKN STRATOCU ON THE WESTERN
EDGE OF MOISTURE SHIELD TO OUR EAST. MAY SCATTER OR EVEN CLEAR OUT
BRIEFLY LATE...BUT EXPECT ANY CLEARING TO ALLOW SOME REDEVELOPMENT
TOMORROW. BASES WILL REMAIN VFR THROUGHOUT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 5 PM MONDAY TO 8 PM EDT TUESDAY FOR INZ021-
029>031-036>042-045>049-054>057-063>065-072.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP/RYAN
SHORT TERM...CP
LONG TERM....MK
AVIATION...NIELD
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
622 PM EDT SUN OCT 28 2012
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 332 PM EDT SUN OCT 28 2012
QUIET WEATHER UNDER HIGH PRESSURE RIDGE WILL GIVE WAY TO WINDY
CONDITIONS AND CHANCES FOR PRECIPITATION AS HURRICANE SANDY GETS
CLOSER. THE WINDIEST CONDITIONS CAN BE EXPECTED FROM MONDAY
EVENING THROUGH TUESDAY EVENING. CHANCES FOR RAIN WILL ARRIVE ON
TUESDAY AND REMAIN THROUGH WEDNESDAY WITH THE GREATEST CHANCES IN
THE NORTHEAST. THE WEATHER AFTER SANDY/S EXIT WILL BE DRY UNTIL
SATURDAY NIGHT WITH TEMPERATURES INCREASING TO NEAR NORMAL FOR THE
WEEKEND.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 622 PM EDT SUN OCT 28 2012
STRATOCU HAS BEEN STEADILY EXPANDING BACK WEST ACROSS CENTRAL
INDIANA FOR THE LAST FEW HOURS. NAM AND OP GFS GUIDANCE BOTH
CONTINUE TO BREAK UP THE LOWER CLOUDS ACROSS MUCH OF THE FORECAST
AREA TOWARDS MIDNIGHT AS SOME SUBSIDENCE DEVELOPS OVER THE REGION
WITH THE ONGOING CONSOLIDATION OF HURRICANE SANDY AND THE UPPER
LEVEL TROUGH OVER THE OHIO VALLEY. MOST RECENT RAP GUIDANCE HOWEVER
SUGGESTIVE THAT CLOUDS MAY LINGER BEYOND MIDNIGHT AND SATELLITE
TRENDS OVER THE LAST FEW HOURS WOULD TEND TO SUPPORT THAT IDEA AS
WELL. HAVE BUMPED UP CLOUD GRIDS EXTENSIVELY FOR THIS EVENING WITH
DECREASING CLOUDS THEREAFTER ALL BUT WESTERN PORTIONS OF THE
FORECAST AREA. WILL MONITOR CLOUD TRENDS OVER THE NEXT FEW HOURS AND
REVISIT POTENTIAL FOR ADDITIONAL CHANGES TO THE CLOUD FORECAST LATER
THIS EVENING.
REST UNCHANGED...PREVIOUS DISCUSSION FOLLOWS.
FORECAST FOCUS TONIGHT IS ON TEMPERATURES. COULD FLIRT WITH FREEZING
IN THE WEST WITH LESS CLOUD COVER THAN LAST NIGHT BUT THINK WINDS
STAYING UP WILL KEEP SIGNIFICANT DECOUPLING FROM OCCURRING AND KEEP
TEMPERATURES FROM FALLING TOO FAR. MORE CLOUDS EXPECTED IN THE EAST
WITH CLOUD BANDS ASSOCIATED WITH SANDY MAKING THEIR WAY HERE AND
HIGH PRESSURE STILL TO OUR WEST. WIND GUSTS OF THE AFTERNOON SHOULD
DROP OFF SUNSET BUT SUSTAINED WINDS SHOULD STAY UP AROUND 10 MPH OR
MORE OVERNIGHT WITH AN INCREASING PRESSURE GRADIENT.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
ISSUED AT 332 PM EDT SUN OCT 28 2012
FORECAST FOCUS IS ON WINDS MONDAY THROUGH TUESDAY AND POPS TUESDAY
THROUGH WEDNESDAY. AS SANDY TREKS NORTHWESTWARD AND GETS CLOSER TO
INDIANA WITH HIGH PRESSURE STILL ENTRENCHED OVER THE CENTRAL AND
WESTERN U.S. THE PRESSURE GRADIENT ACROSS THE AREA WILL TIGHTEN
CONSIDERABLY. GUIDANCE FROM THE MET IS SHOWING SUSTAINED WINDS OF
25-30 MPH ACROSS THE NORTHERN AND EASTERN COUNTIES. NAM SOUNDINGS
SHOW POTENTIAL FOR WIND GUSTS OF 40-50 MPH AS WELL. IN THE NAM THESE
BEGIN AROUND 18Z MONDAY...IN THE GFS AROUND 0Z TUESDAY. THE NAM
STARTS WEAKENING THE WINDS BY AS EARLY AS 18Z TUESDAY BUT THE GFS
DOESN/T BEGIN WEAKENING UNTIL AFTER 0Z WEDNESDAY AS THE NAM WEAKENS
SANDY FASTER THAN THE GFS OR THE ECMWF ONCE IT MAKES LANDFALL. SINCE
THE ECM IS ALSO FAVORING THE STRONGER SOLUTION WILL KEEP THE WINDS
UP THROUGH 0Z SIMILAR TO THE GFS BEFORE SLOWLY DECREASING THEM
TUESDAY NIGHT. THESE STRONGER WINDS ARE SHOWING UP ACROSS THE
NORTHEASTERN HALF TO TWO THIRDS OF CENTRAL INDIANA WHILE THE SOUTH
AND WEST WILL HAVE WINDS BUT NOT QUITE AS STRONG SINCE THEY ARE
FURTHER FROM THE LOW. THUS ISSUING A WIND ADVISORY FROM 21Z MONDAY
THROUGH 0Z WEDNESDAY FOR THE NORTHEASTERN HALF OR SO OF THE AREA.
MODELS ARE IN GOOD AGREEMENT ON KEEPING THE AREA DRY MONDAY AND MOST
OF MONDAY NIGHT. A LITTLE MOISTURE ARRIVES IN THE EASTERN COUNTIES
JUST PRIOR TO 12Z ON TUESDAY BUT ECMWF IS SLOWER WITH THIS. FORCING
IN NAM AND GFS LAGS THE MOISTURE SOME AND THUS THINK KEEPING DRY FOR
NOW PRIOR TO 12Z IS WAY TO GO. FROM TUESDAY THROUGH WEDNESDAY KEEP
POPS GOING WITH HIGHEST VALUES IN THE NORTHEAST CLOSEST TO SANDY AND
TAPERING TO DRY IN THE CENTRAL AND SOUTHWEST. BEST FORCING AND
CHANCE FOR PRECIP APPEARS TO BE IN NORTHEAST ON TUESDAY AND TUESDAY
NIGHT. LOWER CHANCES ON WEDNESDAY AS SANDY WEAKENS.
AS FAR AS TEMPERATURES ARE CONCERNED ALLBLEND CAPTURED 850 MB
TEMPERATURES AND SKY COVER TRENDS WELL WITH HIGHS IN THE MIDDLE 40S
TO LOWER 50S AND LOWS IN THE MIDDLE TO UPPER 30S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
ISSUED AT 224 PM EDT SUN OCT 28 2012
THE MAIN CHALLENGE TO THE LONG TERM WILL BE POPS FIRST WITH THE
REMNANTS OF SANDY WEDNESDAY NIGHT AND SECOND FROM A SOUTHERN SYSTEM
LATE IN THE WEEKEND.
THE 12Z GFS...GEFS AND 00Z ECMWF ARE MUCH CLOSER WITH THE CENTER OF
SURFACE LOW PRESSURE FROM THE REMNANTS OF SANDY THAN THE 12Z
CANADIAN AS IS PREFERRED. THE FORMER BLEND WHICH MATCHES UP WELL
WITH THE REGIONAL OUTPUT. THE BLEND HAS THE REMNANTS NEAR
SOUTHEASTERN ONTARIO AT 12Z THURSDAY WITH QPF ACROSS OUR FAR
NORTHEAST WEDNESDAY NIGHT WHICH LOOKS GOOD. SHOULD JUST BE RAIN
SHOWERS BASED ON MODEL SOUNDINGS. THEN...HIGH PRESSURE ACROSS THE
MISSISSIPPI VALLEY WILL FINALLY BE ABLE TO MOVE EAST ACROSS THE OHIO
VALLEY THROUGH THE FIRST HALF OF THE WEEKEND AS THE REMNANTS OF
SANDY LIFT NORTHEAST INTO NEW ENGLAND AND THE CANADIAN MARITIMES.
THE SECOND HALF OF THE WEEKEND WILL SEE TEMPERATURES WARM AGAIN TO
NEAR NORMAL WITH LITTLE CLOUD COVER AND SOUTHWEST FLOW AHEAD OF A
SOUTHERN SYSTEM THAT COULD BRING SOME MORE RAIN SHOWERS IN BY
SATURDAY NIGHT. FOR NOW...WITH THE UNCERTAINTY AND AFTER
COORDINATION...ONLY WENT WITH SLIGHT CHANCE POPS. REGIONAL OUTPUT
TEMPERATURES LOOK OK AND LEFT ALONE WITH AFTERNOON HIGHS WARMING TO
THE UPPER 50S NORTHEAST TO THE MID 60S SOUTHWEST AFTER STARTING OFF
ONLY IN THE UPPER 40S AND MID 50S THURSDAY.
&&
.AVIATION /DISCUSSION FOR THE 28/21Z TAF UPDATE/...
ISSUED AT 442 PM EDT SUN OCT 28 2012
NO SIGNIFICANT CHANGES NECESSARY. PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 1146 AM EDT SUN OCT 28 2012
VFR CONDITIONS THROUGH THE TAF PERIOD. THE MAIN CONCERN WILL BE
WINDS AS AFTER 14Z TOMORROW AS SANDY GETS CLOSER TO SHORE RESULTING
IN A TIGHTENING PRESSURE GRADIENT ACROSS CENTRAL INDIANA. ONLY
CLOUDS WILL BE CIRRUS AND SCATTERED DIURNAL CU WITH BASES AROUND 4K
FEET.
WINDS WILL BE NORTH NEAR 15 KNOTS WITH GUSTS TO 20 KNOTS OR SO THIS
AFTERNOON AND NORTH AND NORTHWEST AROUND 10 KNOTS TONIGHT.
FINALLY...TOMORROW AFTER 14Z...WINDS WILL REALLY PICK UP FROM THE
NORTH AND NORTHWEST SUSTAINED TO AROUND 20 KNOTS WITH GUSTS TO
AROUND 30 KNOTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 5 PM MONDAY TO 8 PM EDT TUESDAY FOR INZ021-
029>031-036>042-045>049-054>057-063>065-072.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP/RYAN
SHORT TERM...CP
LONG TERM....MK
AVIATION...MK/NIELD
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
130 PM EDT SUN OCT 28 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 446 AM EDT SUN OCT 28 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF EXTENDING FROM
MANITOBA S THRU THE MISSISSIPPI VALLEY. MINOR SHORTWAVE AND
ASSOCIATED INVERTED SFC TROF ACROSS SD INTO NRN MN IS AIDING AN
AREA OF SNOW OVER NRN MN. OTHERWISE...IT`S A QUIET NIGHT WEATHER
WISE ACROSS THE UPPER GREAT LAKES. SFC HIGH PRES IS COVERING THE
AREA FROM SRN SASKATCHEWAN/MANITOBA INTO THE UPPER GREAT LAKES...
RESULTING IN LIGHT/CALM WIND ACROSS UPPER MI EARLY THIS MORNING.
WITH 850MB TEMPS AROUND -9C...OVERWATER INSTABILITY IS SUFFICIENT
FOR LES...BUT SFC BASED WELL-MIXED LAYER EVIDENT ON UPSTREAM 00Z
KINL SOUNDING IS A BIG NEGATIVE. AS A RESULT...KMQT RADAR HAS ONLY
HINTED AT SOME SPRINKLES/FLURRIES OVER ERN LAKE SUPERIOR INTO NE
UPPER MI DURING THE OVERNIGHT. NOTHING MORE THAN SOME HIGH CLOUDS
ACROSS PORTIONS OF THE W AND CNTRL FCST AREA HAS ALLOWED TEMPS TO
PLUMMET INTO THE UPPER TEENS IN SOME OF THE TRADITIONAL COLD SPOTS.
QUIET WEATHER WILL BE THE RULE IN THE SHORT TERM HAS SFC HIGH PRES
DOMINATES THE AREA. THE AREA OF SNOW IN NRN MN WILL WEAKEN AND LIFT
NE TODAY...PASSING W OF THE FCST AREA. MEANWHILE...IF THERE ARE ANY
SPRINKLES/FLURRIES MOVING ONSHORE TO THE E OF MARQUETTE...THOSE WILL
DISSIPATE BY AFTN AS AIRMASS MODIFIES SLIGHTLY. IN THE END...EXPECT
A MIX OF CLOUDS AND SUN WITH TEMPERATURES RISING TO 40-45...WARMEST
SCNTRL.
WITH ANOTHER NIGHT OF LIGHT/CALM WIND...FAVORED THE LOWER SIDE OF
GUIDANCE TONIGHT FOR MINS. TEMPS SHOULD FALL BACK TO THE MID/UPPER
TEENS IN THE TRADITIONAL COLDS SPOTS OVER THE W HALF INTERIOR.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 446 AM EDT SUN OCT 28 2012
MAIN SHOW FOR THE LONG TERM IS WITH REMNANTS OF HURRICANE SANDY
MOVING INTO THE CWA TUE AND WED...WITH LITTLE TO NO SIGNIFICANT
CHANGES TO FORECAST THINKING FROM THE LAST COUPLE OF SHIFTS.
STARTING WITH MON...THINGS LOOKS PRETTY QUIET OVER THE CWA AS A SFC
RIDGE SITS OVER UPPER MI. NO SIGNIFICANT PRECIP IS EXPECTED MON AND
MON NIGHT.
SANDY MAKES LANDFALL LATE MON INTO MON NIGHT OVER OR NEAR NJ...THE
SYSTEM THEN SPINS OVER SE PA THROUGH 06Z WED BEFORE SHIPPING N TO
FAR SRN QUEBEC BY 12Z THU. MOISTURE WILL WRAP AROUND THE SYSTEM AS
THE SYSTEM PUSHES THE SFC RIDGE AXIS FROM OVER THE CWA TO JUST NW OF
THE CWA. BEING BETWEEN THE LOW AND THE RIDGE WILL KEEP WINDS
GENERALLY NLY/NELY TUE AND WED AS THE PRESSURE GRADIENT INCREASES.
THE TRICKIEST PART OF THE FORECAST WITH THIS SYSTEM WILL BE THE
PRECIP CUT OFF OVER THE W CLOSER TO THE SFC RIDGE AND AN UPPER
RIDGE...AND PRECIP TYPE AS MODELS SHOW A RIBBON OF COLDER AIR OVER
THE CENTRAL CWA THAT WOULD BE SUPPORTIVE OF SNOW. WILL FOCUS IN A
BIT MORE ON THESE DETAILS.
FOR PRECIP CHANCES...DEEP MOISTURE WILL FIRST ROTATE INTO THE CWA
FROM E TO W AROUND 12Z TUE AND WILL REACH PEAK DEPTH INTO THE CWA
WED EVENING. QUESTION IS HOW FAR W WILL THE MOISTURE GO. ALL MODELS
SHOW A SHARP CUT OFF FROM NEAR 100 PERCENT 1000-700MB RH EAST TO
LESS THAN 20 PERCENT RH WEST. THE 00Z/28 GFS IS THE FARTHEST W WITH
THE CUT OFF...BRINGING HIGHER RH VALUES OVER ALL OF THE CWA...WHILE
THE 12Z/27 ECMWF IS ON THE E SIDE OF GUIDANCE WITH THE TRANSITION
FROM MOIST TO DRY OVER THE CENTRAL CWA. THE 00Z/28 NAM IS MORE IN
BETWEEN THE GFS AND ECMWF WITH THE CUT OFF CLOSER TO THE ECMWF THAN
THE GFS. LIKE THE PREVIOUS FORECAST POPS THAT COVER WRN UPPER MI IN
SLIGHT CHANCE POPS AND HAVE LIKELY POPS OVER NCENTRAL AND ERN UPPER
MI. GIVEN THE GOOD MOISTURE OVER AT LEAST THE ERN HALF OF THE
CWA...STRONG CYCLONIC NNELY FLOW /AND RESULTING UPSLOPE FLOW IN
HIGHER TERRAIN AREAS/ AND COOL 900-850MB TEMPS THAT WILL RESULT IN
DELTA T VALUES AROUND 7-10C THESE LIKELY POPS ARE CERTAINLY
JUSTIFIED...AND WILL INCREASE THESE SOME.
BEST CHANCES FOR MIXED PRECIP WILL BE TUE NIGHT AS NEAR SFC TEMPS
COOL INTO THE LOW TO MID 30S UNDER THE SUB-FREEZING LAYERS ABOVE
OVER THE NCENTRAL CWA. OVER THE E...WARMER AIR WILL WRAP AROUND THE
SYSTEM AT AROUND 800MB...AND SHOULD BE DEEP AND WARM ENOUGH TO KEEP
MOST PRECIP RAIN. HOWEVER...OVER THE ERN CWA...SOME OF THE PRECIP
COULD FALL AS SLEET BEFORE THE DEEPER WARM AIR ARRIVES SINCE 900MB
TEMPS WILL BE AROUND -3C. BACK TO THE NCENTRAL...ESPECIALLY THE
HIGHER TERRAIN...IT APPEARS PRECIP WILL LIKELY BE ALL SNOW TUE NIGHT
INTO EARLY WED. AGREE THAT BEST BET FOR SNOWFALL AMOUNTS LOOKS TO BE
ON THE LOW SIDE IN THE 1-3 INCH RANGE GIVEN THAT THE SNOW GROWTH
ZONE WILL BE AT 550-500MB AND OUT OF THE BEST LIFT FROM UPSLOPE/LAKE
ENHANCEMENT AND THAT SFC TEMPS WILL BE NEAR OR ABOVE FREEZING.
STILL...THERE IS POTENTIAL FOR INCREASED SNOWFALL AMOUNTS IF ALL
FACTORS LINE UP. THIS WOULD LIKELY CAUSE SOME SLOPPY DRIVING
CONDITIONS FOR THE WED MORNING COMMUTE SO WILL KEEP MENTION IN THE
HWO.
WINDS WILL BE ANOTHER IMPORTANT ASPECT WITH THIS SYSTEM. 925MB WINDS
GREATER THAN 30KTS MOVES IN FROM E TO W LATE MON INTO MON
NIGHT...WITH 925MB WINDS OF 40-45KTS OVER ERN UPPER MI FROM AROUND
09Z TUE TO AROUND 06Z WED. THESE HIGHER WINDS SHOULD HAVE A BETTER
CHANCE AT MIXING TO THE SFC OVER LAND DURING THE DAY ON TUE BUT
EXPECT MOST GUSTS TO BE 40MPH OR LESS...WITH POTENTIAL FOR SOME
50MPH GUSTS. OVER LAKE SUPERIOR AND NW LAKE MI...EXPECT GUSTS TO
REMAIN BELOW 40KTS SINCE WE WILL SEE WARM ADVECTION AND THE SYSTEM
WILL BE WEAKENING...NOT THE TYPICAL SIGNAL FOR STRONG LAKE WINDS.
ECMWF MOVES THE PRECIP OUT BY LATE WED NIGHT WHILE THE GFS KEEP
PRECIP INTO EARLY THU AFTERNOON. WILL GO CLOSER TO THE PREVIOUS
FORECAST AND THE ECMWF FOR POPS ON THU.
UNCERTAINTY INCREASES FOR FRI AND SAT...AND WITH HIGHER IMPACT
EARLIER IN THE WEEK...JUST USED CONSENSUS OF MODELS FOR THE LATER
PERIODS OF THE FORECAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 126 PM EDT SUN OCT 28 2012
HIGH PRES RIDGE OVER THE AREA WILL CONTINUE TO DOMINATE THRU THIS
FCST PERIOD MAINTAINING VFR CONDITIONS AND LIGHT WINDS AT
KIWD/KCMX/KSAW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 446 AM EDT SUN OCT 28 2012
HIGH PRES RIDGE EXTENDING S THRU CNTRL LAKE SUPERIOR TODAY/TONIGHT
AND THEN DRIFTING W TO WRN LAKE SUPERIOR MON WILL LEAD TO LIGHT
WINDS UNDER 20KT. PRES GRADIENT WILL TIGHTEN A BIT OVER THE FAR E
MON...SO WINDS THERE SHOULD RISE UP TO 15-25KT. MON NIGHT THRU
THU...THE HIGH PRES RIDGE WILL DRIFT A LITTLE FARTHER W.
MEANWHILE...POWERFUL LOW PRESSURE MOVING ONSHORE OVER THE MID
ATLANTIC STATES MONDAY NIGHT WILL WEAKEN AS IT MOVES TO THE LOWER
GREAT LAKES LATE WEDNESDAY AND INTO SOUTHERN QUEBEC THURSDAY.
ALTHOUGH WEAKENING...TIGHTENING PRES GRADIENT AND EXPANDING WIND
FIELD AROUND STORM SYSTEM WILL LIKELY LEAD TO NORTHERLY GALES OVER
ROUGHLY THE E HALF OF LAKE SUPERIOR MON NIGHT THRU EARLY WED. A FEW
FACTORS WILL KEEP WINDS IN CHECK. FIRST...SYSTEM WILL BE WEAKENING
QUICKLY AFTER IT MOVES ONSHORE OVER THE MID ATLANTIC STATES.
SECOND...THERE ARE NO STRONG DYNAMICS AFFECTING THE UPPER GREAT
LAKES...AND THIRD THERE IS NO CAA. SO...PROBABLY WON`T SEE GALES
OVER 35-40KT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM MONDAY EVENING THROUGH WEDNESDAY MORNING FOR
LSZ251-267.
GALE WATCH FROM LATE MONDAY NIGHT THROUGH WEDNESDAY MORNING FOR
LSZ249-250-266.
LAKE MICHIGAN...
GALE WATCH FROM MONDAY EVENING THROUGH WEDNESDAY MORNING FOR
LMZ221-248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
645 PM EDT SUN OCT 28 2012
.SYNOPSIS...
HURRICANE SANDY WILL COME ONSHORE ALONG THE THE NEW JERSEY SHORE
ON MONDAY AND MOVE INTO PENNSYLVANIA ON TUESDAY. THIS WILL SPREAD
HIGH WINDS AND HEAVY RAINS INTO OUR AREA INTO WEDNESDAY...WITH
LIGHTER WINDS AND RAIN THROUGH THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
630 PM UPDATE...OUTER EFFECTS FROM SANDY ALREADY BEING FELT ACROSS
LUZERENE CO PA WITH STEADY RAIN MOVING IN. LATEST HI RES MODELS
ARE DOING AN OK JOB CAPTURING THIS RAIN...WITH THE HRRR BEING THE
BEST...BUT IT IS STILL TOO FAR SOUTH AND WEST AND KEEPS IT MAINLY
CLOSE BUT JUST OUT OF OUR CWA. THINKING THAT THE TIMING AND
ORIENTATION LOOKS GOOD (SE TO NW BAND OF RAIN) BUT WILL BUMP IT
ABOUT 50 MILES FARTHER TO THE NORTHEAST THIS MEANS RAIN LIKELY
FROM LUZERENE...LACKAWANNA...WYOMING COUNTIES IN NEPA...THEN
MOVING TO THE NW INTO THE WESTERN FINGER LAKES LATER TONIGHT.
PREVIOUS AFD IS BELOW...
OLD BNDRY CONTS TO BE STALLED OVER WRN NY. THIS FEATURE HAS BEEN
WELL HANDLED BY THE MODELS AND HAS KEPT THE FCST AREA FROM BEING
INVOLVED IN THE PRE RAIN. XPCT THIS BNDRY TO STAY WELL WEST OF THE
AREA OVRNGT. MEANWHILE...BANDS OF LGT RAIN HAS PUSHED THRU THE CNTRL
AND SRN ZONES THRU THE DAY...BUT IT LOOKS LIKE DRIER AIR OVER THE
NE ZONES INTO NEW ENGLAND WILL HOLD FAST OR EVEN PUSH SWWRD OVRNGT
LIMITING THE RAINFALL TO THE XTRM SE ZONES THRY THE NEAR TERM. ANY
PCPN THAT FALLS SHD BE FAIRLY LGT.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
LTL DOUBT NOW IN THE TRACK OF SANDY WITH A NJ CST LANDFALL AND A
STALL IN SRN/CNTRL PA. THIS KEEPS THE FCST AREA IN THE RGT FNT
QUAD OF THE STORM...CREATING MORE CONCRN FOR WINDS BUT LESS FOR
RAINFALL.
WINDS ARE VERY STRONG WITH NAM MODEL SNDG FCSTS OF 70 KTS IN THE
UNSTABLE LYR NEAR THE GND DURING THE PK PD AFT 00Z TUE. THIS SHD
TRANSLATE TO 30 TO 40 MPH SUSTAINED AND A SOME GUSTS NEAR OR OVER
60 MPH. WITH THE ELY DIRECTION...TREES THAT HAVE GROWN TO
WITHSTAND WEST WIND MAY BE COMPROMISED BY THIS STRONG EAST FLOW.
LOW BEGINS TO FILL RAPIDLY WITH THE GRADIENT LOOSENING
CONSIDERABLY BY 00Z WED.
PCPN LOOKS TO PEAK OVER THE UPSLOPE AREAS OF THE WRN CATS AND
POCONOS...WITH SOME SHADOWING EVIDENT DOWNSTREAM...ESP OVER CNTRL
NY. ALSO...THERE/S SCNDRY PCPN PEAK OVER THE WRN ZONES. IN
GNRL...NOT ENUF FCSTD QPF TO CAUSE ANYTHING OTR THAN SOME MINOR
FLOODING..AT WORST. HWVR...WITH A TROPICAL SYSTEM...NEVER DEEL
COMPLETELY COMFORTABLE WITH ANY RAINFALL FCST. ALSO...IT/S DFCLT
TO FCST THE AMT OF EXTRA PCPN WILL BE GENERATED BY THE TERRAIN.
FLOOD WATCH WILL BE CONTD.
MON WILL START WITH A CONTD INFLOW OF MOISTURE JUST SOUTH OF THE
FCST AREA...WHICH WILL THEN LIFT NWRD AS SANDY APRCHS. THEN... STEADY
RAIN CONTS THRU TUE AS SANDY STALLS OVER PA. MODELS DO CONT TO
SHOW SOME DRIER AIR OVER THE NRN ZONES BUT IN GNRL...CAT POPS
JUSTIFIED THRU TUE WITH THE HIGHEST PCPN AMTS OVER THE PA ZONES
AND UPSLOPE AREAS.
LINGERING LGTR PCPN CONTS THRU WEDS SANDY CONTS TO FILL AND LIFT
NWRD. NOT ENUF COLD AIR AVBL ALOFT...AND CERTAINLY NOT AT THE
SFC...FOR ANY MENTION OF SNOW.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
SHORT DISCUSSION DUE TO NEAR TERM CONCERNS. USED HPC GUIDANCE
WITH LTL CHG. HPC FCSTS LOOKED VERY GOOD IN ADVERTISING THE WANING
INFLUENCE OF SANDY...WHICH WILL AFFECT OUR AREA INTO FRIDAY. FCST
TEMPS ARE A LTL WARMER REDUCING THE CHCS FOR SNOW TO MIX IN LATE IN
THE PD (THU NGT/FRI MRNG).
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
LOW CONFIDENCE IN THE FCST SPCLY W/RESPECT TO THE 18-24Z TIME
FRAME THIS AFTN. FNTL BNDRY IS SLOWLY PUSHING WWD. IFR/LIFR CIGS
PERSIST TO THE W OF THIS BNDRY...WITH IMPRVMNT TO VFR NOTED AT RME
AND ALSO AT NORWICH AND SIDNEY. THE BACKEDGE OF THESE LOWER CIGS
IS FCST TO RETROGRADE THIS AFTN...TO A PSN NEAR OR JUST WEST OF A
SYR/BGM LINE. LATER THIS AFTN...LOW LVL MSTR IS ALSO FCST TO INCRS
ACRS FAR SE ZONES.
BOTTOM LINE IS THAT IFR/MVFR CONDITIONS ARE FCST TO PERSIST...WITH
SOME BRIEF IMPRVMNT THIS AFTN AT BGM/SYR/RME. ON MON...SYR/RME
COULD STAY LOW END VFR THRU 18Z...BUT ELSEWHERE MVFR/IFR WITH RAIN
MOVG INTO SRN NY AND NE PA DURING THE MRNG AND EARLY AFTN AS SANDY
APRCHS.
WINDS TNGT N TO NE ARND 10 KTS...INCRNG TO NE 15-25 BY LATE MON
MRNG.
OUTLOOK...
MON NGT/TUE...IFR IN RAIN AND FOG.
WED/THU...MVFR IN SHRA.
FRI...MVFR IN -SHRA MAINLY ACRS CNTRL NY.
&&
.HYDROLOGY...
FLOOD WATCH CONTINUES FOR NE PA...AND OUR NY COUNTIES BELOW THE
THRUWAY.
GIVEN EXPECTED PATH OF SANDY THROUGH NJ/SRN PA DURG ITS STGST
PHASE...THE HEAVIEST RAIN (4+" BASIN AVG) SHOULD STAY MAINLY S OF
OUR FCST AREA...ALTHOUGH POINT TOTALS NEAR 4" ARE CERTAINLY PSBL.
BOTTOM LN...WE`RE LIKELY LOOKING AT MINOR RIVER FLOODING FOR
CERTAIN PTS...AND PERHAPS ISOLD FLASH FLOODING. FOR FURTHER
DETAILS...REFER TO THE SHORT-TERM SECTION ABV.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...HIGH WIND WARNING FROM 2 PM MONDAY TO 5 PM EDT TUESDAY FOR
PAZ038>040-043-044-047-048-072.
FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
PAZ038>040-043-044-047-048-072.
NY...HIGH WIND WARNING FROM 2 PM MONDAY TO 5 PM EDT TUESDAY FOR
NYZ009-015>018-022>025-036-037-044>046-055>057-062.
FLOOD WATCH FROM MONDAY MORNING THROUGH TUESDAY EVENING FOR
NYZ015>017-022>025-044>046-055>057-062.
&&
$$
SYNOPSIS...DGM
NEAR TERM...DGM/HEDEN
SHORT TERM...DGM
LONG TERM...MSE/RRM
AVIATION...
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
152 PM EDT SUN OCT 28 2012
.SYNOPSIS...
HURRICANE SANDY WILL MOVE ONSHORE OVER NEW JERSEY ON MONDAY NIGHT
AND THEN TRACK ACROSS CENTRAL PENNSYLVANIA TO NEW YORK TUESDAY AND
WEDNESDAY. THIS LARGE STORM WILL DOMINATE THE WEATHER ACROSS
NORTHERN OHIO AND NORTHWEST PENNSYLVANIA FOR MUCH OF THE COMING
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CONTINUING WITH THEME OF PREVIOUS UPDATE...WILL ENHANCE POPS MORE
FURTHER TO THE WEST AS BEST ENHANCED BAND HAS SET UP FROM NEAR
MADISON SW TO NEAR MT VERNON AND IS MAKING STEADY PROGRESS TO THE
NW. BOTH RUC AND HRRR SEEM TO BE ON TOP OF THIS SO WILL GENERALLY
USE AVERAGE OF THEIR QPF FIELDS TO DETERMINE POPS FOR REST OF TODAY.
SOME SMALL BREAKS IN CLOUDS OVER WEST THIRD OF THE AREA BUT SHOULD
FILL BACK IN FROM EAST TO WEST. TEMPS NOT LIKELY TO RISE MUCH FOR
EAT HALF OF THE AREA SO WILL ADJUST DOWN A LITTLE THERE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
SHORT TERM PERIOD WILL BE QUITE ACTIVE WITH THE REMNANTS OF SANDY
MOVING THROUGH PA INTO NEW YORK MONDAY NIGHT THROUGH WEDNESDAY
ALTHOUGH BY WEDNESDAY THE WIND FIELD WEAKENS CONSIDERABLY.
FOLLOWED THE NAM12 THROUGH MUCH OF THE SHORT TERM PERIOD. TO BE
BRIEF...POPS WILL BE CATEGORICAL FOR MOST OF THE SHORT TERM PERIOD
ACROSS THE EASTERN TWO THIRDS OF THE AREA. THE WESTERN THIRD WILL
BE CLOSER TO THE DRY AIR AND WILL WAVER BETWEEN SLIGHT CHANCE AND
LIKELY DEPENDING ON MOISTURE DEPTH ON THE NAM. BIG PROBLEM WILL BE
OF COURSE THE WIND AND FLOOD POTENTIAL WITH THE STORM. WILL
CONTINUE WITH THE HIGH WIND WATCH AS GUIDANCE CONTINUES TO SUPPORT
WINDS OF 30 TO 30 MPH WITH GUSTS TO /OVER 50 KNOTS. AREA WHERE NO
HIGH WIND WATCH IS IN EFFECT COULD STILL SEE WIND ADVISORY
CRITERIA SO WILL NEED TO CONTINUE TO MONITOR FOR THE POSSIBILITY.
BASED ON NUMERICAL GUIDANCE...HIGHEST WIND TIMING WOULD BE MONDAY
NIGHT THROUGH TUESDAY MID/LATE AFTERNOON. ALSO CONTINUE TO LIKE THE
FLOOD WATCH PLACEMENT. 5 DAY FORECAST FROM HPC IS 3 TO 4+ INCHES
ACROSS NORTHEAST OHIO AND NWRN PA. SIMILAR TO THE WIND
TIMING...BEST POTENTIAL FOR HEAVY RAIN WILL COME MONDAY NIGHT AND
POSSIBLY INTO EARLY TUESDAY. ALSO GIVEN THE WAVES EXPECTED ON LAKE
ERIE COMBINED WITH THE FACT THAT WINDS WILL BE FROM THE NORTH FOR
A GOOD PORTION OF THE STORM...WILL ISSUE A LAKESHORE FLOOD WATCH.
HIGH TEMPS IN THE 40S TO NEAR 50. LOWS IN THE 30S. JUST AN ASIDE
HERE...850MB TEMPS DO DROP TO -3C OR SO ACROSS THE WESTERN
COUNTIES LATE SUNDAY NIGHT AND AGAIN MONDAY NIGHT BUT
REALLY...THIS TIME OF YEAR...WOULD PREFER LOWER 850MB TEMPS BEFORE
FORECASTING SNOW. SO FOR NOW WILL KEEP PRECIP ALL RAIN.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
BEGINNING THURSDAY...THE REMNANT LOW FROM SANDY WILL BEGIN MOVING
AWAY TO THE NORTHEAST...BUT CYCLONIC FLOW WITH TROUGH STILL OVER THE
AREA WILL ALLOW FOR CLOUDS AND SCATTERED SHOWERS...BEST CHANCE
ACROSS NE OH/NW PA...TO CONTINUE. KEPT LIKELY POPS ACROSS THE
NORTHEAST WITH CHC TRENDING BACK TO THE SOUTH AND WEST. LOOKS LIKE
FRIDAY WILL BEGIN THE TRANSITION LOSING THE INFLUENCE OF THE LOW AND
UPPER TROUGH WITH RIDGING ALOFT BUILDING IN. DIDN/T WANT TO GET TOO
SPECIFIC GIVEN HOW FAR OUT...BUT THINKING POPS MENTIONED IN THE
FORECAST FOR FRIDAY...ESPECIALLY ACROSS THE EAST MAY BE MORE DURING
THE MORNING WITH IMPROVING IN THE AFTERNOON. CLOUDS BUILD BACK INTO
THE AREA FRIDAY NIGHT WITH A WARM FRONT MOVING ACROSS THE AREA. WENT
WITH DRY CONDITIONS FOR SAT AT THIS POINT...BUT LOOKS LIKE PRECIP
WILL BE QUICKLY BUILDING TOWARD THE AREA LATE IN THE DAY. OVERALL
MADE ADJUSTMENTS TO PREVIOUS FORECAST TEMPS COMPARED TO MEX GUIDANCE.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY
RAIN ASSOCIATED WITH UPPER TROF OVER THE AREA...MOVING WEST BUT
SHOULD HAVE A TOUGH TIME REACHING TOL AND FDY. IFR CONDITIONS
INCREASING FROM EAST TO WEST AND MAINLY FOR CEILINGS WITH
VISIBILITIES MAINLY MVFR. RAIN FROM SANDY WILL START MONDAY. WINDS
WILL BE A LITTLE GUSTY AND START INCREASING MONDAY MORNING.
OUTLOOK...NON-VFR MONDAY AFTERNOON THROUGH WEDNESDAY.
&&
.MARINE...
NORTHERLY WINDS ARE EXPECTED TO GRADUALLY INCREASE TOWARD 30 KNOTS
BY LATE TODAY. WINDY CONDITIONS WITH HIGH WAVES WILL CONTINUE
THROUGH THE FORECAST PERIOD. NO CHANGES TO HEADLINES WITH THIS
FORECAST ISSUANCE WITH MODELS CONTINUING TO SHOW THE POSSIBILITY FOR
STORM FORCE WINDS ON THE LAKE MONDAY NIGHT THROUGH EARLY TUESDAY
AFTERNOON. OVERALL MADE ONLY SMALL ADJUSTMENTS TO WINDS...BUT NEW
GUIDANCE CONSISTENT WITH PREVIOUS FORECAST AND SEE LITTLE REASON TO
ADJUST IN EITHER DIRECTION. WAVES WILL BE SIGNIFICANT ACROSS THE
LAKE FROM LATE MONDAY THROUGH MIDDAY TUESDAY...WITH 18 FEET A STRONG
POSSIBILITY. WINDS ARE EXPECTED TO SUBSIDE BELOW GALE FORCE THROUGH
TUESDAY NIGHT AND EARLY WEDNESDAY WHILE SHIFTING TO THE NORTHWEST.
WINDS WILL TURN TO THE WEST THROUGH WEDNESDAY. SMALL CRAFT
CONDITIONS ARE EXPECTED TO DIMINISH FROM WEST TO EAST ON FRIDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...HIGH WIND WARNING FROM NOON MONDAY TO 4 PM EDT TUESDAY FOR
OHZ003-006>014-017>023-027>033-036>038-047-089.
LAKESHORE FLOOD WARNING FROM NOON MONDAY TO 8 PM EDT TUESDAY
FOR OHZ003-007>012-089.
FLOOD WATCH FROM LATE TONIGHT THROUGH TUESDAY EVENING FOR
OHZ009>014-019>023-029>033-038-047-089.
PA...HIGH WIND WARNING FROM NOON MONDAY TO 4 PM EDT TUESDAY FOR
PAZ001>003.
LAKESHORE FLOOD WARNING FROM NOON MONDAY TO 8 PM EDT TUESDAY
FOR PAZ001.
FLOOD WATCH FROM LATE TONIGHT THROUGH TUESDAY EVENING FOR
PAZ001>003.
MARINE...STORM WARNING FROM NOON MONDAY TO 10 AM EDT TUESDAY FOR LEZ061-
142>149-162>169.
SMALL CRAFT ADVISORY UNTIL NOON EDT MONDAY FOR LEZ142>149.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK
SHORT TERM...TK
LONG TERM...ABE
AVIATION...KIELTYKA
MARINE...ABE
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
233 PM CDT SUN OCT 28 2012
.SHORT TERM...TONIGHT AND MONDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SPRAWLING
AREA OF HIGH PRESSURE STRETCHING FROM TEXAS TO WISCONSIN TO HUDSON
BAY EARLY THIS AFTERNOON. LIGHT PRECIP IS OCCURRING OVER MINNESOTA
ALONG A WEAK SURFACE TROUGH...AND ASSOCIATED CLOUD COVER IS
STRUGGLING TO PUSH INTO NORTH-CENTRAL WISCONSIN AS IT RUNS INTO
DRIER AIR. IN ADDITION...LAKE CLOUDS ARE ALSO STRUGGLING TO MOVE
INLAND FROM THE LAKE MICHIGAN SHORELINE. SINCE HIGH PRESSURE IS
PROJECTED TO REMAIN NEARLY STATIONARY OVER THE NEXT 24 HOURS...TEMPS
AND CLOUD COVER REMAIN THE MAIN FORECAST CONCERNS.
TONIGHT...HIGH PRESSURE RIDGE AXIS WILL REMAIN STATIONARY OVER N-C
TO SW WISCONSIN TONIGHT. SHORTWAVE TROUGH OVER WESTERN ONTARIO WILL
BE LIFTING OFF TO THE NORTHEAST WHILE SUBSIDENCE INCREASES OVER
EASTERN WISCONSIN AND LAKE MICHIGAN. AS A RESULT...MID AND HIGH
CLOUDS OVER THE NORTHERN MISSISSIPPI VALLEY WILL STRUGGLE TO MOVE
EAST INTO THE AREA...AND ANTICIPATE THEM DISSIPATING/THINNING AS
THEY APPROACH CENTRAL WISCONSIN. WILL STILL HAVE BRISK NORTH WINDS
ALONG THE LAKE MICHIGAN SHORELINE THAT WILL KEEP TEMPS UP COMPARED
TO FARTHER WEST. SOME LAKE CLOUDS MAY BRUSH THE SHORELINE...THOUGH
DO TURN A BIT MORE NORTHERLY OVERNIGHT WHICH SHOULD KEEP THEM
CONFINED TO THE LAKESHORE. IN THE END...WENT WITH MOSTLY CLEAR
SKIES THOUGH WITH LOWS A COUPLE DEGREES WARMER THAN LAST NIGHT.
MONDAY...HIGH PRESSURE DOESNT MOVE MUCH ON MONDAY. SUBSIDENCE
CONTINUES TO INCREASE THROUGH THE DAY WHILE SANDY MOVES EAST...WHICH
WILL TIGHTEN THE PRESSURE GRADIENT OVER EASTERN WISCONSIN. NORTH
WINDS WILL BE MORE GUSTY OVER EASTERN WISCONSIN THAN TODAY AS A
RESULT. PERHAPS A FEW DIURNAL CLOUDS COULD POP UP OVER N-C
WISCONSIN THANKS TO ONSHORE FLOW OFF LAKE SUPERIOR...BUT ANTICIPATE
A MOSTLY SUNNY DAY WITH HIGHS A COUPLE DEGREES WARMER THAN TODAYS
READINGS.
.LONG TERM...MONDAY NIGHT THOUGH NEXT SUNDAY.
AGAIN THE AFFECTS FROM POST-TROPICAL CYCLONE SANDY ARE THE FOCUS
OF THIS FORECAST PERIOD. MODELS CONTINUE SAME TRENDS BRINGING
SANDY INLAND OVER NJ LATE MONDAY AFTN...THEN HAVE IT MEANDER INTO
WEST/CENTRAL MD/PA. MAIN CONCERN WITH WINDS...THEN PCPN CHANCES
OVER CWA AS "SANDY" PUSHES WEST .
HIGH PRESSURE OUT OF HUDSON BAY WITH ASSOCIATED DRY AIR MASS WILL
CONTINUE OVER WI INTO TUE NIGHT. GRADIENT BETWEEN HIGH AND "SANDY"
TO TIGHTEN MONDAY NIGHT WITH WINDS PICKING UP OVER THE EASTERN
PART OF THE STATE. AT THIS POINT...HAVE MARGINAL CONDITIONS FOR
WIND ADVISORY OVER DOOR CTY IN THE GRIDS AND THAT IS NOT REACHED
UNTIL 12Z TUE..THUS WILL PASS OFF ANY HEADLINES TO NEXT SHIFT.
HAVE BACKED OFF ON POPS/CLOUDS THROUGH THE TUE TO WED PERIOD AS
BOTH EC AND NAM CROSS SECTIONS RATHER DRY FROM 850-500 MB...WHILE
ALSO INDICATING SUBSIDENCE OVER WESTERN ZONES.
"SANDY" TO EXIT SLOWLY WED NIGHT...THU. HAVE TRENDED TOWARDS EC
LATER PERIODS WITH SLOWER SOLUTION WITH GFS BEING TO PROGRESSIVE
GIVEN CURRENT PATTERN IN THE ATLANTIC. STILL LOOKING AT TEMPS
WARMING TO NORMAL OR SLIGHTLY ABOVE FOR LATER HALF OF WEEK.
&&
.AVIATION...FOR THE 12Z TAF ISSUANCE. OTHER THAN THE POSSIBILITY
OF SOME MVFR CONDITIONS WITH LAKE CLDS NEAR LAKE MICHIGAN...VFR
CONDITIONS EXPECTED.
&&
.MARINE...NO CHANGE TO MARINE HEADLINES WITH GALE CONDITIONS
EXPECTED BY TUE MORNING ON THE LAKE. WAVES WILL LIKELY HIT SMALL
CRAFT CONDITIONS LATER MON AFTN...MAY NEED TO ISSUE SEPARATE SCA
IF START OF GALE PUSHED OFF LATER INTO MON NIGHT.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MPC/TE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1225 PM CDT SUN OCT 28 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
222 AM CDT SUN OCT 28 2012
MAIN FORECAST CONCERNS REMAIN ON CLOUDS AND TEMPERATURES WITH THE
BLOCKED WEATHER PATTERN IN PLACE.
CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING ALONG THE WEST COAST OF THE U.S....TROUGHING FROM
MANITOBA SOUTH THROUGH THE FORECAST AREA AND INTO ARKANSAS...STRONG
RIDGING OVER NEWFOUNDLAND AND HURRICANE SANDY OFF THE SOUTH CAROLINA
COASTLINE. WITHIN THE TROUGHING...MAIN SHORTWAVES OF NOTE ARE ONE
CROSSING THE FORECAST AREA AND THE OTHER AT THE BASE OF THE TROUGH
IN ARKANSAS. THE SHORTWAVE CROSSING THE FORECAST AREA HAS BEEN
PRODUCING SCATTERED CIRRUS CLOUD COVER...WITH DRY AIR ON 00Z
SOUNDINGS FROM MPX AND GRB PREVENTING ANY OTHER CLOUDS. TO THE WEST
OF THE SHORTWAVE...A COLLECTION OF LOW TO MID CLOUDS ARE PRESENT
OVER THE EASTERN DAKOTAS AND WESTERN MINNESOTA...ASSOCIATED WITH
ISENTROPIC LIFT SITUATED AROUND 285K. AIRMASS REMAINS COOL UNDER THE
UPPER TROUGHING WITH 00Z SOUNDINGS AT MPX...GRB AND DVN ALL NEAR
-7C. AT THE SURFACE...A RIDGE OF HIGH PRESSURE ENCOMPASSES MUCH OF
THE UPPER MISSISSIPPI RIVER VALLEY REGION AND SOUTH INTO THE KANSAS
CITY AREA.
TODAY THROUGH MONDAY...THE WEATHER PATTERN OVER THE FORECAST AREA
WILL GET BLOCKED UP...DUE TO:
1. RIDGING NEAR THE WEST COAST MOVING INTO MUCH OF THE WESTERN U.S.
2. HURRICANE SANDY PHASING AND STRENGTHENING NEAR NEW JERSEY WITH
THE UPPER TROUGHING CURRENTLY IN MISSOURI AND ARKANSAS.
AS A RESULT...THE SURFACE HIGH PRESSURE RIDGE OVER THE AREA WILL GO
NOWHERE. IN ADDITION...THE LOW TO MID-LEVEL DRY AIR SEEN ON 00Z
SOUNDINGS WILL GO NOWHERE TOO...PREVENTING PRECIPITATION. NOTE...
THERE MAY BE SOME MID CLOUDS TRYING TO ENTER WESTERN SECTIONS OF THE
FORECAST AREA ON MONDAY...BUT THESE LOOK TO THIN AS THEY RUN INTO
SUBSIDENCE AND BLOCKING PRODUCED ON THE WEST SIDE OF SANDY. A FEW
MID CLOUDS MAY ENTER WESTERN SECTIONS OF THE FORECAST AREA THIS
MORNING...BUT THESE LOOK TO DISSIPATE THIS AFTERNOON AS THE
ISENTROPIC LIFT AIDING THEM SHIFTS OFF TO THE NORTH. 500MB HEIGHTS
ARE FORECAST TO RISE DURING THE NEXT 48 HOURS WHICH SHOULD HELP TO
GET A LITTLE WARMER AIR INTO THE AREA. 850MB TEMPS REFLECT THIS BY
CLIMBING TO -4 TO -6C AT 18Z TODAY AND TO -1 TO -4C AT 18Z MONDAY.
THUS...HIGHS SHOULD WARM A FEW DEGREES EACH DAY...TOPPING OUT IN THE
MID 40S TODAY AND MID TO UPPER 40S ON MONDAY. LOWS TONIGHT HAVE THE
POTENTIAL TO BE QUITE COOL GIVEN MOSTLY CLEAR SKIES...LIGHT WINDS
AND DRY AIR IN PLACE. THUS...STAYED ON THE COOL SIDE OF
GUIDANCE...ESPECIALLY FOR THE TYPICAL COLD SPOTS IN WISCONSIN.
MONDAY NIGHT THROUGH TUESDAY NIGHT...THE FIGHT LOOKS TO CONTINUE
BETWEEN THE UPPER RIDGING OVER THE WESTERN U.S. TRYING TO PUSH
EASTWARD...BUT KEEPS RUNNING INTO DEEP CLOSED OFF UPPER TROUGHING
OVER THE EASTERN U.S. CONTAINING THE EXTRATROPICAL STATE OF SANDY.
THUS...THE SURFACE RIDGE OVER THE AREA THROUGH MONDAY STILL LOOKS TO
REMAIN OVERHEAD OR NEARBY. THERE ARE SUGGESTIONS THAT THE RIDGE
COULD RETROGRADE WEST SLIGHTLY...DEPENDING ON THE EXACT EVOLUTION OF
SANDY...RESULTING IN AN INCREASE OF NORTHERLY WINDS OVER EASTERN
PORTIONS OF THE FORECAST AREA ON TUESDAY. AGAIN WITH THE BLOCKING IN
PLACE...NOT ANTICIPATING ANY PRECIPITATION. CLOUD COVER LOOKS
LIMITED TOO...WITH JUST SOME PERIODS OF MID OR HIGH CLOUDS CROSSING
WESTERN PORTIONS OF THE FORECAST AREA. DUE TO THE BLOCKED UP
PATTERN...850MB TEMPS CONTINUE TO RISE JUST SLOWLY...CLIMBING TO +1
TO -2C AT 18Z TUESDAY. THEREFORE...HIGHS ON TUESDAY WILL ONLY END UP
A COUPLE DEGREES AT MOST WARMER THAN MONDAY. LOWS ON THE OTHER HAND
HAVE THE POTENTIAL TO BE QUITE COOL BOTH NIGHTS...AGAIN DUE TO LIGHT
WINDS AND DRY AIR. LOCATIONS WEST OF THE MISSISSIPPI RIVER SHOULD
HAVE SOME PASSING CLOUDS TO LIMIT THE COOLING. IN GENERAL...STAYED
NEAR GUIDANCE FOR LOWS WEST OF THE MISSISSIPPI RIVER AND TOWARDS THE
COLD SIDE OF GUIDANCE EAST OF THE MISSISSIPPI RIVER.
.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT
222 AM CDT SUN OCT 28 2012
28.00Z ECMWF/CANADIAN/GFS AND GFS ENSEMBLES HAVE THE SAME GENERAL
THEME THROUGH THE LONG TERM PERIOD ON THE UPPER LEVEL PATTERN...BUT
THERE ARE MAJOR TIMING ISSUES. MUCH OF THE PROBLEM IN THE LONG TERM
PERIOD IS HOW AND WHEN THE DEEP EASTERN U.S. TROUGHING AND
EXTRATROPICAL SANDY LIFTS OUT. ALL MODELS KEEP STRONG RIDGING IN THE
DAVIS STRAIGHT AREA INTO THE WEEKEND...SO ANY EJECTION OF THAT DEEP
EASTERN U.S. TROUGHING SHOULD BE SLOW TO OCCUR. AT THE SAME TIME
THERE IS SUBTROPICAL RIDGING OVER THE WESTERN U.S. GETTING PUSHED
EASTWARD BY TROUGHING COMING INTO CALIFORNIA OFF THE PACIFIC. IT IS
THIS TROUGH WHICH WE HAVE TO WATCH FOR POTENTIAL PRECIPITATION
TOWARDS THE WEEKEND. MODELS DIFFER GREATLY ON HOW FAR EAST THAT
TROUGHING MAKES IT...WITH THE 28.00Z GFS MUCH MORE AGGRESSIVE THAN
THE 27.12Z/28.00Z ECMWF...SUGGESTING IT LIFTS INTO OUR AREA FOR THE
WEEKEND. FOR NOW...HAVE STAYED TOWARDS THE ECMWF WHICH HAS SUPPORT
FROM SOME OF THE GFS ENSEMBLE MEMBERS.
IN SUMMARY...THE AREA LOOKS TO STAY DRY WITH HIGH PRESSURE MOSTLY
DOMINATING AT THE SURFACE. FOR THE WEEKEND...THERE MAY BE A CHANCE
OF HAVING SOME WARM ADVECTION PRECIPITATION...BUT THE SIGNAL IS VERY
WEAK AND MOSTLY SOUTH OF THE AREA. THUS...A DRY FORECAST CONTINUES.
TEMPERATURES SHOULD CONTINUE TO GRADUALLY WARM DUE TO BOTH AIRMASS
MODIFICATION AND THEN WARM ADVECTION TOWARDS THE WEEKEND. NOTE THAT
THERE IS POTENTIAL FOR A COLD FRONT TO COME THROUGH THE AREA ON
SATURDAY FROM THE NORTHWEST...AS INDICATED IN THE 27.12Z/28.00Z
ECMWF. THIS FRONT COULD DEFLECT SOME OF THE WARMER AIR TRYING TO
COME UP INTO THE AREA ON FRIDAY. FOLLOWED THE CONSENSUS FOR
TEMPERATURES WHICH BRINGS HIGHS BACK TO NEAR NORMAL BY THURSDAY THEN
HOLDS THEM STEADY INTO THE WEEKEND.
&&
.AVIATION...THIS AFTERNOON THROUGH MONDAY
1225 PM CDT SUN OCT 28 2012
VFR CONDITIONS TO PERSIST THRU MON AS THE SFC-700MB RIDGE AXIS
REMAINS OVER WI/IA. WINDS TO REMAIN QUITE LIGHT WITH THE LOW LEVEL
RIDGE AXIS OVER/NEAR THE AREA. MID LEVEL MOISTURE AHEAD OF THE NEXT
SHORTWAVE MOVING ACROSS THE NORTHERN ROCKIES SPREADS INTO THE AREA
LATER TONIGHT/MON...WITH AN INCREASE OF CLOUDS IN THE 7K-10K FT
RANGE EXPECTED OVER THE TAF SITES INTO MONDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
222 AM CDT SUN OCT 28 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....RRS