Forecast Discussions mentioning any of
"HRRR" "RR" "RUC13" "RUC" received at GSD on 11/27/11
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
241 PM PST FRI NOV 25 2011
.DISCUSSION...AS OF 2:35 PM PST FRIDAY...RATHER MUNDANE WEATHER
PATTERN SETTING UP OVER THE REGION THROUGH NEXT WEEK WITH A
WARMING TREND.
DESPITE A SOMEWHAT DAMP START THIS MORNING WITH LIGHT
RAIN...PRECIP ENDED BY MORNING WITH SOME SCATTERED OF CLOUDS.
HOWEVER...SAN FRANCISCO BAY NORTHWARD CONTINUES TO STRUGGLE FOR
SUNSHINE. AS A RESULT...MANY LOCATIONS ARE REMAINING RATHER COOL.
DO EXPECT SOME THINNING OF THE CLOUD COVER OVER THE NEXT FEW HOURS
WITH AN UPTICK IN TEMPERATURE. MOUNTAIN VIEW SOUTHWARD ON THE THE
OTHER HAND IS CURRENTLY EXPERIENCING WALL TO WALL SUNSHINE WITH
TEMPERATURES IN THE 60S.
SHORT TERM(TONIGHT-MONDAY)...
THE FRONTAL BOUNDARY FROM THIS MORNING WILL CONTINUE TO DISSIPATE
THIS EVENING. THE MAIN WEATHER CONCERN FOR TONIGHT WILL BE RESIDUAL
BOUNDARY LAYER MOISTURE AIDING IN FOG DEVELOPMENT. FOR NOW...WILL
KEEP PATCHY DENSE FOG POSS FOR PORTIONS OF THE EAST BAY AND INTO
THE DELTA AS A RESULT OF POSS CENTRAL VALLEY FOG. NORTH BAY WILL
HAVE A CHANCE FOR PATCHY FOG AS WELL...BUT PROBABLY NOT AS DENSE.
IF THE CLOUD COVER CURRENTLY OVER THE NORTH BAY DOES NOT DISSIPATE
FOG DEVELOPMENT MAY BE HAMPERED. LOCATIONS OVER THE SOUTHERN
PORTION OF THE CWA ARE LESS LIKELY TO SEE VALLEY FOG. FLOW OVER
THIS REGION APPEARS TO BE SLIGHTLY OFFSHORE AT 925 MB AND BOUNDARY
LAYER MOISTURE IS LESS.
OTHERWISE...LITTLE CHANGE WAS MADE TO THE SHORT TERM FORECAST. THE
LONG WAVE PATTERN CONTINUES TO SHOW A DECENT RIDGE OF HIGH PRESSURE
BUILDING OVER THE REGION. A GRADUAL WARMING AND DRYING TREND CAN
BE EXPECTED. BY SUNDAY AND MONDAY...MODEL GUIDANCE EVEN INDICATES
850 TEMPS 16.5-18 C. THEREFORE HAVE RAISED TEMPERATURES SLIGHT FOR
MAX TEMPS. HOWEVER...DO NOT EXPECT FULL POTENTIAL OF 18C TO
REALIZED GIVEN THE REDUCE AMOUNT OF INSOLATION THIS TIME OF YEAR.
LONG TERM(TUESDAY-FRIDAY)...
THE MILD WEATHER HOLDS ON FOR TUESDAY AND PART OF WEDNESDAY AS
HIGH PRESSURE REMAIN. MEDIUM RANGE MODELS BREAK DOWN THE RIDGE AS
A LOW BEGINS TO DROP S OVER THE PAC NW. THERE ARE DIFFERENCE
AMONGST THE MODELS...BUT ALL SUGGEST COOLER WEATHER. THE REAL
QUESTION WILL BE IF THERE IS ANY PRECIP WITH THE PASSING UPPER LOW
FROM THE N OR THE CUT OFF LOW OFF THE COAST? CURRENT FORECAST WILL
REMAIN DRY BUT THE ECMWF DOES INDICATE A FEW HUNDREDTHS POSS NEXT THURSDAY.
&&
.AVIATION...AS OF 9:35 AM PST FRIDAY...A LARGE AREA OF STRATUS
WILL CONTINUE TO IMPACT KSJC NORTHWARD THROUGH AT LEAST 19Z. THE
NAM...WRF...AND HRRR INDICATE CLEARING AT THE AIRPORTS ANYWHERE
FROM 19Z TO 21Z...SO THERE IS AN INCREASED CONFIDENCE THAT THERE
WILL BE SUNNY SKIES THIS AFTERNOON. OTHERWISE...NEARLY STAGNANT
FLOW OVER THE REGION WILL BRING LIGHT AND VARIABLE WINDS. A FEW OF
THE SHORT TERM MODELS ARE HINTING AT GROUND FOG FORMING
OVERNIGHT...LOW CONFIDENCE.
VICINITY OF KSFO...MVFR CIGS AROUND 1500 FEET WILL PREVAIL THROUGH
AT LEAST 19Z. MODERATE CONFIDENCE. LIGHT AND VARIABLE WINDS THIS
AFTERNOON. POSSIBLE LOW CLOUDS OR GROUND FOG OVERNIGHT AT BOTH
TERMINALS. LOW CONFIDENCE.
KSFO BRIDGE APPROACH...MVFR CIGS THROUGH 20Z. OTHERWISE...SIMILAR
TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR CONDITIONS WILL PREVAIL THROUGH
AT LEAST 01Z. SHORT TERM MODELS INDICATE PATCHY GROUND FOG WILL
DEVELOP LATE THIS EVENING INTO THE OVERNIGHT HOURS. LOW CONFIDENCE.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...PT ARENA TO PIGEON PT 10-60 NM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM
SCA...ROUGH BAR ADVISORY FOR SF BAR
&&
$$
PUBLIC FORECAST: MM
AVIATION/MARINE: RILEY
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
939 AM PST FRI NOV 25 2011
.DISCUSSION...AS OF 8:33 AM PST FRIDAY...THE MAIN WEATHER FEATURE
OF NOTE THIS MORNING IS A WEAK DISSIPATING COLD FRONT CURRENTLY
DRAPED OVER THE BAY AREA. AS NOTED EARLIER THIS MORNING...THERE IS
LITTLE FANFARE ASSOCIATED WITH THE COLD FRONT OTHER THAN VERY
LIGHT RAIN. IN FACT...THE PRECIP IS VERY SHALLOW WITH NO RADAR
RETURNS. HOWEVER...AUTOMATED GAUGES INDICATE A FEW HUNDREDTHS OVER
THE LAST SIX HOURS AND A HUNDREDTH OR TWO OVER THE LAST HOUR. ALL
RAINFALL HAS BE OBSERVED NORTH OF GILROY. THE COLD FRONT ALSO
HELPED TO INCREASE THE BOUNDARY LAYER RH WHICH HAS RESULTED IN
SOME PATCHY FOG AROUND SF BAY AND THE N BAY VALLEYS. WILL DO A
MORNING UPDATE TO FRESHEN UP THE WORDING WITH VALLEY FOG AND TO
REMOVE IT IN THE SALINAS VALLEY.
OTHERWISE...THE COLD FRONT WILL CONTINUE TO WASH OUT OVER THE CWA
WITH A GRADUAL CLEARING THROUGH THE AFTERNOON. TEMPERATURES WILL
REMAIN SEASONABLE COOL AND IN THE LOWER 60S. THERE AFTER...A
RATHER BENIGN WEATHER PATTERN WILL BE ESTABLISHED ACROSS MUCH OF
CALIFORNIA AS STRONG HIGH PRESSURE BUILDS IN THROUGH NEXT WEEK. A
GRADUAL WARMING TREND CAN BE EXPECT THROUGH WEEKEND WITH NIGHT AND
MORNING VALLEY FOG.
&&
.AVIATION...AS OF 9:35 AM PST FRIDAY...A LARGE AREA OF STRATUS
WILL CONTINUE TO IMPACT KSJC NORTHWARD THROUGH AT LEAST 19Z. THE
NAM...WRF...AND HRRR INDICATE CLEARING AT THE AIRPORTS ANYWHERE
FROM 19Z TO 21Z...SO THERE IS AN INCREASED CONFIDENCE THAT THERE
WILL BE SUNNY SKIES THIS AFTERNOON. OTHERWISE...NEARLY STAGNANT
FLOW OVER THE REGION WILL BRING LIGHT AND VARIABLE WINDS. A FEW OF
THE SHORT TERM MODELS ARE HINTING AT GROUND FOG FORMING
OVERNIGHT...LOW CONFIDENCE.
VICINITY OF KSFO...MVFR CIGS AROUND 1500 FEET WILL PREVAIL THROUGH
AT LEAST 19Z. MODERATE CONFIDENCE. LIGHT AND VARIABLE WINDS THIS
AFTERNOON. POSSIBLE LOW CLOUDS OR GROUND FOG OVERNIGHT AT BOTH
TERMINALS. LOW CONFIDENCE.
KSFO BRIDGE APPROACH...MVFR CIGS THROUGH 20Z. OTHERWISE...SIMILAR
TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR CONDITIONS WILL PREVAIL THROUGH
AT LEAST 01Z. SHORT TERM MODELS INDICATE PATCHY GROUND FOG WILL
DEVELOP LATE THIS EVENING INTO THE OVERNIGHT HOURS. LOW CONFIDENCE.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...PT ARENA TO PIGEON PT 10-60 NM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM
SCA...ROUGH BAR ADVISORY FOR SF BAR UNTIL 3 PM
&&
$$
PUBLIC FORECAST: MM
AVIATION/MARINE: RILEY
AREA FORECAST DISCUSSION
NWS ALBANY NY
133 AM EST FRI NOV 25 2011
.SYNOPSIS...
THE WEATHER PATTERN WILL BE TRANQUIL FOR THIS HOLIDAY WEEKEND WITH
HIGH PRESSURE REMAINING IN CONTROL ALONG THE EASTERN SEABOARD.
TEMPERATURES WILL SLOWLY MODERATE TO ABOVE NORMAL AS SOUTHERLY WINDS
INCREASE. THE NEXT CHANCE FOR SHOWERS ARRIVES LATE SUNDAY INTO
MONDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 1 AM...ONLY SOME MINOR ADJUSTMENTS BASED ON OBSERVATIONAL
DATA...FORECAST ON TRACK.
AS OF 1000 PM EST...THE IR SATELLITE PICTURE SHOWS SOME THIN CIRRUS
MOVING ACROSS ERN NY. NORTH AND WEST OF THE CAPITAL REGION... SOME
STRATUS IS STILL LINGERING OVER THE ADIRONDACKS. THE MOSTLY CLEAR
SKIES AND LIGHT TO CALM WINDS HAVE ALLOWED SOME PATCHY RADIATIONAL
FOG FORMATION OVER MUCH OF THE FCST AREA. THE SFC SOILS ARE STILL
A BIT WET FROM THE HVY RAINFALL ON TUESDAY NIGHT-WED. THE FOG IS
MOST ROBUST OVER THE LAKE GEORGE REGION...AND EAST OF THE SRN
GREEN MTNS. WE HAVE ADDED PATCHY FOG OVERNIGHT FOR LOCATIONS LESS
THAN 1000 FEET ACROSS ERN NY AND WRN NEW ENGLAND. TEMPS VARY
WIDELY ACROSS THE REGION WITH MINS REACHED OR EXCEEDED OVER THE
LAKE GEORGE REGION...AND THE BERKSHIRES. WE HAVE BROUGHT MINS DOWN
A FEW DEGREES WHERE IT RADIATED QUICKLY OVER THE LAKE GEORGE
REGION...NRN AND CNTRL TACONICS...AND THE BERKSHIRES. EXPECT LOWS
TO RANGE FROM THE M20S TO M30S ACROSS THE REGION. A WEAK THERMAL
TROUGH WILL MOVE THROUGH THE REGION OVERNIGHT...AND WE ARE SEEING
WINDS INCREASE FROM THE S/SW OVER W-CNTRL NY. TEMPS MAY ACTUALLY
CREEP UP A FEW DEGREES TOWARD SUNRISE.
PREVIOUS NEAR TERMS...
AS OF 630 PM EST...HAPPY THANKSGIVING TO ALL ! HIGH PRESSURE AT
THE SFC CONTINUES TO RIDGE IN FROM THE TN VALLEY AND THE MID
ATLANTIC REGION. A WEAK IMPULSE IN THE H500 W/NW FLOW ALOFT
CONTINUES TO MOVE ACROSS THE ERN GREAT LAKES REGION...AND UPSTATE
NY. THE STRATUS IS HANGING TOUGH ON THE 11-3.9 MICRON SATELLITE
LOOP NORTH AND WEST OF THE CAPITAL REGION. WE INCREASED THE CLOUD
COVER THROUGH MIDNIGHT OVER THE SRN AND WRN DACKS. THE NAM12 MODEL
SOUNDINGS...AND RH PROFILES INDICATE THIS STRATUS WILL HANG ON.
THE OTHER ISSUE TO DEAL WITH IS THE SKIES CLEARING...AND THE WINDS
GOING LIGHT TO CALM FROM THE HUDSON RIVER VALLEY EASTWARD. KGFL HAS
DROPPED TO ABOUT 30F WITH SOME PATCHY FOG FORMING. WE ADDED SOME
PATCHY FOG TO THE KGFL GENERAL AREA...AND TO THE CT RIVER VALLEY
EAST OF THE SRN GREEN MTNS. HOURLY TRENDS WERE REDONE BASED ON
OBSERVATIONS FOR T/TD/RH/APPARENT TEMPS. ASIDE FOR A FEW CIRRUS
FROM THE CAPITAL REGION SOUTH AND EAST OVERNIGHT...EXPECT TEMPS TO
COOL INTO THE U20S TO M30S.
PREVIOUS NEAR TERM...
STRATUS DECK WAS ALONG THE I90 CORRIDOR AS OF 19Z. THIS CLOUD DECK
CONTINUES TO SLOWLY ERODE AND MIGRATE NORTHWARD THIS AFTERNOON.
NCEP MODEL SUITE AND HOURLY RUC13 LOW LEVEL RH FIELDS SUGGEST THIS
STRATUS DECK SHOULD CONTINUE TO LIFT NORTHWARD AND ERODE FURTHER.
MEANWHILE...WARM ADVECTION ALOFT AND ITS ASSOCIATED HIGH AND SOME
MID LEVEL CLOUDS ARE QUICKLY MOVING ACROSS NEW ENGLAND AND
PORTIONS OF UPSTATE NEW YORK. THIS TOO IS EXPECTED TO SLIDE
OFFSHORE TONIGHT LEAVING BEHIND A PTCLOUDY-MOCLEAR SKIES.
BASED ON CURRENT DEWPOINTS...MOS TEMPERATURES LOOK A BIT COOL AND
HAVE FOLLOWED WARMER OVERNIGHT TRENDS WITHIN THE LAV/LAMP
GUIDANCE.
LARGE AREA OF HIGH PRESSURE...CENTERED OVER THE SOUTHEAST
CONUS...WILL BE THE DOMINANT PLAYER FOR THIS NEAR TERM AND INTO
THE SHORT TERM.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
THIS LARGE AREA OF HIGH PRESSURE WILL KEEP THE WEATHER QUIET EAST
OF THE MISSISSIPPI RIVER THROUGH THIS SHORT TERM PERIOD. IN
FACT...RATHER PRONOUNCED WEST-SOUTHWEST FLOW ALONG WITH MILD MID
LEVEL TEMPS WILL RESULT IN TEMPERATURES CLIMBING TOWARD OR
EXCEEDING 10 DEGREES ABOVE CLIMATOLOGY /IN ADDITION...DOWNSLOPING
MAY ENHANCE THESE TEMPS INTO THE VALLEY LOCATIONS/. THE ONLY
COMPLICATION COULD BE SOME OVERNIGHT SHALLOW BR/FG AND A POTENTIAL
FOR SOME LOW LEVEL STRATUS DEVELOPMENT. IN ADDITION...WITH THE
ONGOING WARM ADVECTION...SOME HIGH AND MID LEVEL CLOUD COVER MAY
MOVE ACROSS THE SKY THOUGH THIS PERIOD. EITHER WAY...THE WEATHER
SHOULD HAVE MINIMAL IMPACT TO HOLIDAY WEEKEND TRAVELS.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
ACTIVE WEATHER PATTERN EXPECTED THROUGH THE LONG TERM...BUT MODEL
GUIDANCE HAS DIFFERING SOLUTIONS...SO CONFIDENCE IS LOW. WENT WITH
HPC GUIDANCE.
SFC LOW APPROACHING FROM THE GREAT LAKES REGION SUNDAY MORNING. 12Z
GFS...ECMWF AND GFSENSEMBLE MEMBERS HAVE NOT AGREED UPON A
TRACK...SPEED...OR QPF AMOUNTS. ECMWF HAS THE MORE PROGRESSIVE AND
NORTHERLY TRACK OF SFC LOW...WITH THE COLD FRONT AND PRECIP
ASSOCIATED WITH THE LOW MOVING THROUGH THE FA LATE SUNDAY THROUGH
LATE MONDAY...WITH QPF AMOUNTS AROUND HALF AN INCH OR LESS.
ASSOCIATED UPPER LEVEL POSITIVELY TILTED TROUGH REMAINS OPEN IN
ECMWF.
MEANWHILE...GFS DEVELOPS A CLOSE LOW WITHIN THE UPPER LEVEL TROUGH.
AS THIS TROUGH APPEARS TO HAVE A NEUTRAL TILT...GFS KEEPS IT SLOW
MOVING OVER THE GREAT LAKES REGION...WHERE THE UPPER LEVEL LOW
PRESSURE CENTER REFORMS FURTHER NORTH SUNDAY NIGHT. THE TROUGH
BECOMES NEGATIVELY TILTED BEFORE A PIECE OF SOUTHERLY ENERGY BREAKS
OFF...TRAVELING TOWARDS THE OBX AHEAD OF THE MAIN TROUGH...BY
TUESDAY NIGHT. QPF AMOUNTS UP TO 2 INCHES WITH THE GFS.
CHANCE FOR PRECIP POSSIBLE THROUGH TUESDAY NIGHT/WEDNESDAY WITH GFS
ENSEMBLE MEMBERS SLOWLY MOVE SFC LOW NORTHWARD TOWARDS JAMES BAY.
ALL GUIDANCE SHOW HIGH PRESSURE BUILDING IN JUST SOUTH OF THE
REGION...BUT NO AGREEMENT ON WHEN OR FOR HOW LONG. HPC HAS HIGH
PRESSURE WEDNESDAY INTO THURSDAY.
TEMPS ABOUT 10 DEGREES ABOVE NORMAL TO START THE PERIOD...TRENDING
COOLER TO ABOUT NORMAL BY THE END OF THE PERIOD.
&&
.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
IFR/LIFR CONDITIONS OCCURRING AT KGFL...KAQW...KDDH...KPOU...
AND KRME AT PRESENT...MVFR AT KPSF...AND VFR AT KALB.
LOW STRATUS DECK CONTINUES ACROSS MUCH OF THE ADIRONDACK REGION
INCLUDING SOME OF THE UPPER MOHAWK VALLEY WHILE FARTHER SOUTH
SKIES WERE MOSTLY CLEAR WITH SOME SCTD CIRRIFORM CLOUDS.
RADIATIONAL COOLING AND CALM WINDS WAS CAUSING FOG TO FORM IN
MANY LOCATIONS ACROSS THE REGION.
LOOKS LIKE KGFL WILL BE SOCKED IN FOR THE REST OF THE PREDAWN
PERIOD...DEAD CALM WITH IFR/LIFR CIG AND VSBY FOR THE LAST TWO
HOURS.
KALB...GOOD BET TO DETERIORATE TO MVFR BY 06Z...AND AT THIS
POINT CANNOT RULE OUT IFR DUE TO FOG OR STRATUS. WINDS DEAD
CALM...AND TEMP/DEWPT SPREAD ONLY 1 TO 2 DEGREES...THUS WILL
TEMPO TO IFR BETWEEN 07Z AND 11Z.
KPOU...SKY CURRENTLY CLEAR ASIDE FROM CIRRIFORM CLOUDS...AGAIN
DEAD CALM WINDS AND A 2 DEGREE TEMP/DEWPT SPREAD...SO LOOKING
AT MVFR A GOOD BET AND AGAIN A POSSIBILITY OF IFR DURING THE
PREDAWN PERIOD.
THE GOOD NEWS...SKIES SHOULD BE MOSTLY CLEAR ABOVE THE FOG AND
LOW STRATUS ASIDE FROM SOME STRANDS OF CIRRUS BY SUNRISE. THUS
THE FOG AND LOW STRATUS SHOULD MIX OUT BY 13Z-14Z. A FINE DAY
FOR VFR FLIGHT FOLLOWS WITH STRANDS OF CIRRUS STREAMING IN FROM
A FRONTAL SYSTEM IN THE MISSISSIPPI VALLEY AROUND THE NORTH SIDE
OF A HIGH PRESSURE SYSTEM CENTERED IN THE DEEP SOUTH.
WINDS WILL BE CALM...OR NEARLY SO...DURING THE PREDAWN PERIOD.
THEY WILL BECOME SOUTHERLY 3 TO 6 KNOTS SHORTLY AFTER SUNRISE
AND INCREASE TO AROUND 8 TO 12 KNOTS DURING THE MIDDAY PERIOD.
WINDS WILL THEN SLACKEN THIS EVENING TO LESS THAN 5 KNOTS.
OUTLOOK...
TONIGHT...MOSTLY VFR...SOME MVFR DUE TO LIGHT FOG POSSIBLE LATE.
SAT-SAT NIGHT...VFR. NO SIG WX.
SUN...MAINLY VFR. INCREASING CLDS. CHC PM -SHRAS.
SUN NIGHT-TUE...MVFR/IFR WITH CHC -SHRAS.
&&
.HYDROLOGY...
DRY WEATHER IS EXPECTED THROUGH MOST OF THE LONG HOLIDAY WEEKEND
AS HIGH PRESSURE DOMINATES. OUR NEXT CHANCES FOR WET WEATHER WILL
RETURN LATE IN THE WEEKEND INTO EARLY NEXT WEEK AS A LOW PRESSURE
SYSTEM APPROACHES AND MOVES ACROSS THE REGION. THERE IS A LOT OF
UNCERTAINTY DUE TO DIFFERENCES IN THE MODELS...BUT THERE IS A
POTENTIAL FOR SIGNIFICANT RAINFALL STARTING SUNDAY NIGHT...WITH
ONE TO TWO INCH AMOUNTS NOT OUT OF THE QUESTION. THE LATEST MMEFS
INDICATES SIGNIFICANT WITHIN-BANK RISES ON THE RIVERS BUT STOPPING
SHORT OF REACHING FLOOD.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.CLIMATE...
2011 HAS MOVED UP INTO FIFTH PLACE FOR WETTEST YEARS ON RECORD
FOR ALBANY NEW YORK.
WETTEST YEARS - ALBANY NY - SINCE 1820
1) 55.78 INCHES 1871
2) 55.81 INCHES 1870
3) 51.83 INCHES 1850
4) 49.80 INCHES 1827
5) 49.75 INCHES THROUGH NOVEMBER 23ND
6) 49.37 INCHES 1878
7) 48.35 INCHES 1843
8) 48.22 INCHES 1848
9) 47.79 INCHES 2008
10) 47.72 INCHES 2005
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM/WASULA
NEAR TERM...IAA/BGM/WASULA
SHORT TERM...BGM
LONG TERM...KGM
AVIATION...RCK
HYDROLOGY...RCK/BGM
CLIMATE...IAA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1245 AM EST FRI NOV 25 2011
.SYNOPSIS...
THE WEATHER PATTERN WILL BE TRANQUIL FOR THIS HOLIDAY WEEKEND WITH
HIGH PRESSURE REMAINING IN CONTROL ALONG THE EASTERN SEABOARD.
TEMPERATURES WILL SLOWLY MODERATE TO ABOVE NORMAL AS SOUTHERLY WINDS
INCREASE. THE NEXT CHANCE FOR SHOWERS ARRIVES LATE SUNDAY INTO
MONDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 1000 PM EST...THE IR SATELLITE PICTURE SHOWS SOME THIN
CIRRUS MOVING ACROSS ERN NY. NORTH AND WEST OF THE CAPITAL REGION...
SOME STRATUS IS STILL LINGERING OVER THE ADIRONDACKS. THE MOSTLY
CLEAR SKIES AND LIGHT TO CALM WINDS HAVE ALLOWED SOME PATCHY
RADIATIONAL FOG FORMATION OVER MUCH OF THE FCST AREA. THE SFC
SOILS ARE STILL A BIT WET FROM THE HVY RAINFALL ON TUESDAY NIGHT-WED.
THE FOG IS MOST ROBUST OVER THE LAKE GEORGE REGION...AND EAST OF
THE SRN GREEN MTNS. WE HAVE ADDED PATCHY FOG OVERNIGHT FOR
LOCATIONS LESS THAN 1000 FEET ACROSS ERN NY AND WRN NEW ENGLAND.
TEMPS VARY WIDELY ACROSS THE REGION WITH MINS REACHED OR EXCEEDED
OVER THE LAKE GEORGE REGION...AND THE BERKSHIRES. WE HAVE BROUGHT
MINS DOWN A FEW DEGREES WHERE IT RADIATED QUICKLY OVER THE LAKE
GEORGE REGION...NRN AND CNTRL TACONICS...AND THE BERKSHIRES.
EXPECT LOWS TO RANGE FROM THE M20S TO M30S ACROSS THE REGION. A
WEAK THERMAL TROUGH WILL MOVE THROUGH THE REGION OVERNIGHT...AND
WE ARE SEEING WINDS INCREASE FROM THE S/SW OVER W-CNTRL NY. TEMPS
MAY ACTUALLY CREEP UP A FEW DEGREES TOWARD SUNRISE.
PREVIOUS NEAR TERMS...
AS OF 630 PM EST...HAPPY THANKSGIVING TO ALL ! HIGH PRESSURE AT
THE SFC CONTINUES TO RIDGE IN FROM THE TN VALLEY AND THE MID
ATLANTIC REGION. A WEAK IMPULSE IN THE H500 W/NW FLOW ALOFT
CONTINUES TO MOVE ACROSS THE ERN GREAT LAKES REGION...AND UPSTATE
NY. THE STRATUS IS HANGING TOUGH ON THE 11-3.9 MICRON SATELLITE
LOOP NORTH AND WEST OF THE CAPITAL REGION. WE INCREASED THE CLOUD
COVER THROUGH MIDNIGHT OVER THE SRN AND WRN DACKS. THE NAM12 MODEL
SOUNDINGS...AND RH PROFILES INDICATE THIS STRATUS WILL HANG ON.
THE OTHER ISSUE TO DEAL WITH IS THE SKIES CLEARING...AND THE WINDS
GOING LIGHT TO CALM FROM THE HUDSON RIVER VALLEY EASTWARD. KGFL HAS
DROPPED TO ABOUT 30F WITH SOME PATCHY FOG FORMING. WE ADDED SOME
PATCHY FOG TO THE KGFL GENERAL AREA...AND TO THE CT RIVER VALLEY
EAST OF THE SRN GREEN MTNS. HOURLY TRENDS WERE REDONE BASED ON
OBSERVATIONS FOR T/TD/RH/APPARENT TEMPS. ASIDE FOR A FEW CIRRUS
FROM THE CAPITAL REGION SOUTH AND EAST OVERNIGHT...EXPECT TEMPS TO
COOL INTO THE U20S TO M30S.
PREVIOUS NEAR TERM...
STRATUS DECK WAS ALONG THE I90 CORRIDOR AS OF 19Z. THIS CLOUD DECK
CONTINUES TO SLOWLY ERODE AND MIGRATE NORTHWARD THIS AFTERNOON.
NCEP MODEL SUITE AND HOURLY RUC13 LOW LEVEL RH FIELDS SUGGEST THIS
STRATUS DECK SHOULD CONTINUE TO LIFT NORTHWARD AND ERODE FURTHER.
MEANWHILE...WARM ADVECTION ALOFT AND ITS ASSOCIATED HIGH AND SOME
MID LEVEL CLOUDS ARE QUICKLY MOVING ACROSS NEW ENGLAND AND
PORTIONS OF UPSTATE NEW YORK. THIS TOO IS EXPECTED TO SLIDE
OFFSHORE TONIGHT LEAVING BEHIND A PTCLOUDY-MOCLEAR SKIES.
BASED ON CURRENT DEWPOINTS...MOS TEMPERATURES LOOK A BIT COOL AND
HAVE FOLLOWED WARMER OVERNIGHT TRENDS WITHIN THE LAV/LAMP
GUIDANCE.
LARGE AREA OF HIGH PRESSURE...CENTERED OVER THE SOUTHEAST
CONUS...WILL BE THE DOMINANT PLAYER FOR THIS NEAR TERM AND INTO
THE SHORT TERM.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
THIS LARGE AREA OF HIGH PRESSURE WILL KEEP THE WEATHER QUIET EAST
OF THE MISSISSIPPI RIVER THROUGH THIS SHORT TERM PERIOD. IN
FACT...RATHER PRONOUNCED WEST-SOUTHWEST FLOW ALONG WITH MILD MID
LEVEL TEMPS WILL RESULT IN TEMPERATURES CLIMBING TOWARD OR
EXCEEDING 10 DEGREES ABOVE CLIMATOLOGY /IN ADDITION...DOWNSLOPING
MAY ENHANCE THESE TEMPS INTO THE VALLEY LOCATIONS/. THE ONLY
COMPLICATION COULD BE SOME OVERNIGHT SHALLOW BR/FG AND A POTENTIAL
FOR SOME LOW LEVEL STRATUS DEVELOPMENT. IN ADDITION...WITH THE
ONGOING WARM ADVECTION...SOME HIGH AND MID LEVEL CLOUD COVER MAY
MOVE ACROSS THE SKY THOUGH THIS PERIOD. EITHER WAY...THE WEATHER
SHOULD HAVE MINIMAL IMPACT TO HOLIDAY WEEKEND TRAVELS.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
ACTIVE WEATHER PATTERN EXPECTED THROUGH THE LONG TERM...BUT MODEL
GUIDANCE HAS DIFFERING SOLUTIONS...SO CONFIDENCE IS LOW. WENT WITH
HPC GUIDANCE.
SFC LOW APPROACHING FROM THE GREAT LAKES REGION SUNDAY MORNING. 12Z
GFS...ECMWF AND GFSENSEMBLE MEMBERS HAVE NOT AGREED UPON A
TRACK...SPEED...OR QPF AMOUNTS. ECMWF HAS THE MORE PROGRESSIVE AND
NORTHERLY TRACK OF SFC LOW...WITH THE COLD FRONT AND PRECIP
ASSOCIATED WITH THE LOW MOVING THROUGH THE FA LATE SUNDAY THROUGH
LATE MONDAY...WITH QPF AMOUNTS AROUND HALF AN INCH OR LESS.
ASSOCIATED UPPER LEVEL POSITIVELY TILTED TROUGH REMAINS OPEN IN
ECMWF.
MEANWHILE...GFS DEVELOPS A CLOSE LOW WITHIN THE UPPER LEVEL TROUGH.
AS THIS TROUGH APPEARS TO HAVE A NEUTRAL TILT...GFS KEEPS IT SLOW
MOVING OVER THE GREAT LAKES REGION...WHERE THE UPPER LEVEL LOW
PRESSURE CENTER REFORMS FURTHER NORTH SUNDAY NIGHT. THE TROUGH
BECOMES NEGATIVELY TILTED BEFORE A PIECE OF SOUTHERLY ENERGY BREAKS
OFF...TRAVELING TOWARDS THE OBX AHEAD OF THE MAIN TROUGH...BY
TUESDAY NIGHT. QPF AMOUNTS UP TO 2 INCHES WITH THE GFS.
CHANCE FOR PRECIP POSSIBLE THROUGH TUESDAY NIGHT/WEDNESDAY WITH GFS
ENSEMBLE MEMBERS SLOWLY MOVE SFC LOW NORTHWARD TOWARDS JAMES BAY.
ALL GUIDANCE SHOW HIGH PRESSURE BUILDING IN JUST SOUTH OF THE
REGION...BUT NO AGREEMENT ON WHEN OR FOR HOW LONG. HPC HAS HIGH
PRESSURE WEDNESDAY INTO THURSDAY.
TEMPS ABOUT 10 DEGREES ABOVE NORMAL TO START THE PERIOD...TRENDING
COOLER TO ABOUT NORMAL BY THE END OF THE PERIOD.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
IFR/LIFR CONDITIONS OCCURRING AT KGFL...KAQW...KDDH...KPOU...
AND KRME AT PRESENT...MVFR AT KPSF...AND VFR AT KALB.
LOW STRATUS DECK CONTINUES ACROSS MUCH OF THE ADIRONDACK REGION
INCLUDING SOME OF THE UPPER MOHAWK VALLEY WHILE FARTHER SOUTH
SKIES WERE MOSTLY CLEAR WITH SOME SCTD CIRRIFORM CLOUDS.
RADIATIONAL COOLING AND CALM WINDS WAS CAUSING FOG TO FORM IN
MANY LOCATIONS ACROSS THE REGION.
LOOKS LIKE KGFL WILL BE SOCKED IN FOR THE REST OF THE PREDAWN
PERIOD...DEAD CALM WITH IFR/LIFR CIG AND VISBY FOR THE LAST
TWO HOURS.
KALB...GOOD BET TO DETERIORATE TO MVFR BY 06Z...AND AT THIS
POINT CANNOT RULE OUT IFR DUE TO FOG OR STRATUS. WINDS DEAD
CALM...AND TEMP/DEWPT SPREAD ONLY 1 TO 2 DEGREES...THUS WILL
TEMPO TO IFR BETWEEN 07Z AND 11Z.
KPOU...SKY CURRENTLY CLEAR ASIDE FROM CIRRIFORM CLOUDS...AGAIN
DEAD CALM WINDS AND A 2 DEGREE TEMP/DEWPT SPREAD...SO LOOKING
AT MVFR A GOOD BET AND AGAIN A POSSIBILITY OF IFR DURING THE
PREDAWN PERIOD.
THE GOOD NEWS...SKIES SHOULD BE MOSTLY CLEAR ABOVE THE FOG AND
LOW STRATUS ASIDE FROM SOME STRANDS OF CIRRUS BY SUNRISE. THUS
THE FOG AND LOW STRATUS SHOULD MIX OUT BY 13Z-14Z. A FINE DAY
FOR VFR FLIGHT FOLLOWS WITH STRANDS OF CIRRUS STREAMING IN FROM
A FRONTAL SYSTEM IN THE MISSISSIPPI VALLEY AROUND THE NORTH SIDE
OF A HIGH PRESSURE SYSTEM CENTERED IN THE DEEP SOUTH.
WINDS WILL BE CALM...OR NEARLY SO...DURING THE PREDAWN PERIOD.
THEY WILL BECOME SOUTHERLY 3 TO 6 KNOTS SHORTLY AFTER SUNRISE
AND INCREASE TO AROUND 8 TO 12 KNOTS DURING THE MIDDAY PERIOD.
WINDS WILL THEN SLACKEN THIS EVENING TO LESS THAN 5 KNOTS.
OUTLOOK...
TONIGHT...MOSTLY VFR...SOME MVFR DUE TO LIGHT FOG POSSIBLE LATE.
SAT-SAT NIGHT...VFR. NO SIG WX.
SUN...MAINLY VFR. INCREASING CLDS. CHC PM -SHRAS.
SUN NIGHT-TUE...MVFR/IFR WITH CHC -SHRAS.
&&
.HYDROLOGY...
DRY WEATHER IS EXPECTED THROUGH MOST OF THE LONG HOLIDAY WEEKEND
AS HIGH PRESSURE DOMINATES. OUR NEXT CHANCES FOR WET WEATHER WILL
RETURN LATE IN THE WEEKEND INTO EARLY NEXT WEEK AS A LOW PRESSURE
SYSTEM APPROACHES AND MOVES ACROSS THE REGION. THERE IS A LOT OF
UNCERTAINTY DUE TO DIFFERENCES IN THE MODELS...BUT THERE IS A
POTENTIAL FOR SIGNIFICANT RAINFALL STARTING SUNDAY NIGHT...WITH
ONE TO TWO INCH AMOUNTS NOT OUT OF THE QUESTION. THE LATEST MMEFS
INDICATES SIGNIFICANT WITHIN-BANK RISES ON THE RIVERS BUT STOPPING
SHORT OF REACHING FLOOD.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.CLIMATE...
2011 HAS MOVED UP INTO FIFTH PLACE FOR WETTEST YEARS ON RECORD
FOR ALBANY NEW YORK.
WETTEST YEARS - ALBANY NY - SINCE 1820
1) 55.78 INCHES 1871
2) 55.81 INCHES 1870
3) 51.83 INCHES 1850
4) 49.80 INCHES 1827
5) 49.75 INCHES THROUGH NOVEMBER 23ND
6) 49.37 INCHES 1878
7) 48.35 INCHES 1843
8) 48.22 INCHES 1848
9) 47.79 INCHES 2008
10) 47.72 INCHES 2005
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM/WASULA
NEAR TERM...BGM/WASULA
SHORT TERM...BGM
LONG TERM...KGM
AVIATION...RCK
HYDROLOGY...RCK/BGM
CLIMATE...IAA
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1110 PM CST THU NOV 24 2011
.DISCUSSION...
ISSUED 852 PM CST THU NOV 24 2011
LOW STRATUS IS COMING BACK NORTH...AIDED BY STRONG SOUTHERLY
WINDS. THIS AREA OF CLOUDS IS NOT VERY WIDE SO SOME AREAS IN THE
SOUTHEAST COULD SEE SOME CLEARING OVERNIGHT...WHILE OTHER AREAS
BECOME CLOUDY AGAIN. CURRENT FORECAST SEEMS TO HAVE A GOOD HANDLE
ON THE GOING TRENDS SO NO UPDATE REQUIRED AT THIS TIME.
HOWEVER...HAVE BEEN MAKING ADJUSTMENTS TO THE GRIDS TO BETTER
REFLECT THE CLOUD COVER TRENDS.
AUTEN
&&
.AVIATION...
ISSUED 1110 PM CST THU NOV 24 2011
IFR CIGS/VIS ARE ONCE AGAIN ADVECTING NORTHWARD OVER THE TAF
SITES. DEC/CMI ALREADY DOWN AND EXPECT SPI AND BMI TO BE IFR
AROUND ISSUANCE TIME. UNSURE IF PIA WILL SEE IT GIVEN THE FACT
THAT THE SATELLITE LOOP SEEMS TO INDICATE A SLOWING TREND IN THE
MOVEMENT NORTH. SATELLITE ALSO SHOWS SOME HOLES IN THE STRATUS.
ONCE STRATUS DISSIPATES TOMORROW MORNING VFR CONDITIONS WILL
PREVAIL FOR REMAINDER OF TAF PERIOD. SCATTERED CIRRUS BECOMING
BROKEN AROUND 18Z IS ALL THAT IS EXPECTED. MODELS AND BUFKIT
SOUNDING CONTINUE TO INDICATE LOW LEVEL WIND SHEAR AROUND 1.5KFT
TONIGHT SO WILL KEEP MENTION. ONCE STRATUS CLEARS...EXPECTING
SOUTHERLY WINDS TO INCREASE AND BE GUSTY DURING THE
AFTERNOON...THEN DECREASING AROUND SUNSET. SOUTHERLY WINDS WILL
PREVAIL THROUGH THE PERIOD.
AUTEN
&&
.PREV DISCUSSION...
ISSUED 300 PM CST THU NOV 24 2011
INITIAL CONCERN WILL BE POSSIBLE REDEVELOPMENT OF LOW STRATUS
CLOUDS TONIGHT INTO FRIDAY MORNING. THEN ATTENTION TURNS TO THE
ONSET OF RAIN LATE FRIDAY NIGHT THROUGH SATURDAY AND THE ARRIVAL
OF COLDER AIR FOR MUCH OF THE EXTENDED FORECAST.
SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT.
CHALLENGING FORECAST FOR TONIGHT IN TERMS OF CLOUDS AND RESULTANT
LOW TEMPS. THE ONLY MODELS THAT SEEM TO HAVE A DECENT HANDLE ON
THE LOW LEVEL MOISTURE ARE THE HRRR AND SPC 4KM WRF. BOTH OF THEM
ARE INDICATING CLOUD REDEVELOPMENT ACROSS CENTRAL IL AND EVEN
SURROUNDING PORTIONS OF IL. THE NAM AND GFS SOUNDINGS SHOW A LOW
LEVEL SATURATION AS WELL...BUT SHALLOW. FORECAST WIND TRAJECTORY
FLOWS INDICATE WE SHOULD SEE THE SW RETURN FLOW ORIGINATING WHERE
STRATUS CLOUDS ARE LINGERING THIS AFTERNOON IN MO/AR. A TIGHTER
PRESSURE GRADIENT WOULD TYPICALLY KEEP WINDS UP AT NIGHT...BUT THE
LOW LEVEL INVERSION LOOKS TO BE PLENTY STRONG ENOUGH TO PREVENT
MIXING OVERNIGHT. WILL FORECAST CLOUDS TO REFORM...AND KEEP LOW
TEMPS A COUPLE DEGREES WARMER THAN GUIDANCE.
CLEARING SHOULD COME QUICKER ON FRIDAY AS MORE PROMINENT MIXING
WILL OCCUR UNDER A MUCH STRONGER SFC PRESSURE GRADIENT. PLENTY OF
DRY AIR ALOFT WILL AID IN CLOUD EROSION. WINDY CONDITIONS ARE
EXPECTED WITH SSW GUSTS OVER 30 MPH. TEMPS WILL RESPOND IN KIND AS
WAA FLOWS PUSH 850 MB TEMPS UP NEAR 12C. THAT COUPLED WITH ADDITIONAL
SUNSHINE SHOULD PUT HIGHS INTO THE L-M 60S.
BROAD SCALE ISENTROPIC LIFT AHEAD OF THE NEXT COLD FRONT WILL HELP
PRIME THE ATMOSPHERE FOR RAIN TO DEVELOP W OF THE IL RIVER AFTER
MIDNIGHT FRIDAY NIGHT. HOWEVER...BASED ON FORECAST CONDENSATION
PRESSURE DEFICITS /CPD/...IT STILL APPEARS WE WILL HAVE A 5-7 HOUR
WINDOW OF STEADY RAINS AS THE FRONT PROGRESSES EASTWARD DURING THE
DAY ON SATURDAY. WE WILL CONTINUE WITH CATEGORICAL POPS WEST IN
THE MORNING AND EAST IN THE AFTERNOON. SOME SHOWERS MAY LINGER IN
THE EVENING ACROSS THE EAST...SO WILL CONTINUE WITH CHANCE POPS AS
SUBSIDENT FLOWS BEGIN TO SHUT DOWN MEASURABLE PRECIP.
COLD AIR WILL RETURN ON BRISK NW WINDS SAT NIGHT. MOST OF THE
PRECIP SHOULD COME TO AN END BEFORE THE AIR COLUMN GETS COLD
ENOUGH FOR SNOW. HOWEVER...WE CAN NOT RULE OUT SOME FLURRIES
POSSIBLE AFTER MIDNIGHT SAT NIGHT. BY 12Z SUNDAY...ANOTHER WAVE OF
ISENTROPIC LIFT AND LOW CPD/S IS INDICATED AS THE UPPER TROUGH MOVES
ACROSS IL. ENOUGH RESIDUAL MOISTURE MAY BE PRESENT FOR A FEW LIGHT
RAIN/SNOW SHOWERS AFTER MIDNIGHT...AND FLURRIES NORTH/SPRINKLES
SOUTH ON SUNDAY.
BY SUNDAY NIGHT...ALL PRECIP SHOULD COME TO AN END FROM THIS
SYSTEM...AS THE UPPER TROUGH AXIS FINALLY SLIDES EAST.
LONG TERM...MONDAY THROUGH THURSDAY.
THE EXTENDED FORECAST SHOWS PERSISTENT COLD CONDITIONS AS A CUT
OFF LOW POSSIBLY DEVELOPS ACROSS THE SOUTHERN OHIO RIVER VALLEY.
THERE HAS BEEN A WIDE VARIETY OF SOLUTIONS FROM THE MODELS ON THIS
CUT OFF FEATURE...WITH THE ECMWF AND THE CANADIAN THE MAIN ONES
SHOWING THIS FEATURE. THE ECMWF BEING A BIT MORE PRONOUNCED AND
SLOWER THAN THE CANADIAN. THE GFS KEEPS A PROGRESSIVE PATTERN WITH
NORTHWEST FLOW AND A DRY FRONTAL PASSAGE ON MONDAY NIGHT/TUESDAY
ACROSS IL. DESPITE THE DIFFERING SOLUTIONS...THE OVERALL SENSIBLE
WEATHER LOOKS TO BE ON THE CHILLY SIDE WITH PERIODICALLY BREEZY
CONDITIONS.
SHIMON
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
635 PM CST SAT NOV 26 2011
.UPDATE 27/00Z AVIATION DISCUSSION...
.SHORT TERM /TONIGHT/...
MAIN CONCERN TONIGHT WILL BE TEMP AND WIND TRENDS...AND PRECIP TO A
LESSER EXTENT. PRIMARY PRECIP SHIELD ASSOCIATED WITH CENTRAL CONUS
LONG WAVE TROUGH CURRENTLY EXTENDS FROM SRN PLAINS INTO GREAT LAKES
AND HAS ALL BUT EXITED FORECAST AREA. FORCING WITH THIS IS MAINLY
MID/UPPER LEVEL BASED IN THE FORM OF DPVA AND RIGHT ENTRANCE REGION
DIVERGENCE OF GREAT LAKES JET SEGMENT. RADAR AND SATELLITE TRENDS
DO NOT LOOK PROMISING FOR ADDITIONAL PRECIP THIS EVENING...HOWEVER
MODELS DO SUSTAIN SOME MID LEVEL KINEMATIC FORCING WITH BRIEF SURGE
OF DEEPER MOISTURE SWINGING THROUGH AROUND 00Z OR SHORTLY
THEREAFTER. THUS HAVE KEPT MENTION OF SPRINKLES OR FLURRIES NE
THIRD DURING THE EVENING.
POTENTIAL FOR ADVISORY LEVEL WINDS HAS DECREASED AS WELL...BOTH
SPATIALLY AND TEMPORALLY...WITH ONLY A SITE OR TWO WEST CURRENTLY
VERIFYING. ISALLOBARIC MAX...MAX MSLP GRADIENT...AND MAGNITUDE OF
MIXED LAYER WINDS ALL DECREASE THIS EVENING AS THEY APPROACH THE MO
RIVER SO DO NOT EXPECT ADVISORY CRITERIA WINDS TO CONTINUE AS LONG
OR AS FAR EAST AS PREVIOUSLY ANTICIPATED. THUS HEADLINE NOW ENDS AT
03Z WITH SEVERAL TIERS OF ERN COUNTIES REMOVED.
OUTSIDE OF THE RUC...RAW MODEL TEMPS ARE BEHIND THE CURVE IN TERMS
OF COOLING. HOWEVER EVEN THE COOLER NAM WHICH EVENTUALLY CATCHES UP
TO THE RUC SUGGESTS CLOUDS AND WINDS KEEPING TEMPS ABOVE GUIDANCE.
.LONG TERM /SUNDAY THROUGH SATURDAY/...
IN THE LONG TERM...IT WILL BE FAIRLY QUIET WITH A DRY FORECAST
THROUGH DAY SEVEN. UPPER LEVEL LOW PRESSURE SYSTEM FORECAST BY ALL
MODELS OVER THE SOUTHEAST UNITED STATES HEADS NORTH INTO THE OHIO
VALLEY BY TUESDAY. MEANWHILE...A WEAK NORTHERN STREAM SHORTWAVE
SHOULD CROSS THE NORTHERN PLAINS AND UPPER MIDWEST. UPSTREAM QG
FORCING OVER THE NORTHERN PLAINS SHOULD WEAKEN AS THE WAVE
APPROACHES THE MISSISSIPPI VALLEY AND INTERACTS WITH UPPER LOW
MOVING NORTH INTO THE OHIO VALLEY. THE LACK OF SUSTAINED VERTICAL
MOTION AND LIMITED MOISTURE SHOULD KEEP THE ASSOCIATED COLD FRONT
DRY WITH SOME CLOUDS AS IT CROSSES IOWA. ON MONDAY...AHEAD OF THE
FRONT...WEAK HIGH PRESSURE OVER CENTRAL IOWA BETWEEN THE SYSTEM OVER
THE OHIO VALLEY AND THE APPROACHING COLD FRONT. ONLY MODEST MIXING
SHOULD KEEP TEMPERATURES RELATIVELY COOL CONSIDERING THE THERMAL
CHARACTERISTICS OF THE AIRMASS. GIVEN THE EXPECTED COOL TEMPERATURES
ON MONDAY...ONLY MODEST COOLING IS FORECAST BEHIND THE FRONT ON
TUESDAY. THIS IS PROBABLY DUE TO BETTER MIXING EVEN THOUGH THE
AIRMASS WILL BE COOLER.
MODELS AGREE IN DIGGING AN UPPER LOW OVER THE SOUTHWEST UNITED
STATES DURING THE EXTENDED. THE 12Z ECMWF/GFS SUGGEST NORTHWEST
FLOW OVER THE NORTH CENTRAL UNITED STATES BUT THEY HAVE TIMING
DIFFERENCES WITH SHORTWAVES AND FRONTAL PASSAGES LATE NEXT WEEK.
ALTHOUGH ALL SOLUTIONS LOOK MAINLY DRY FOR CENTRAL IOWA...DAY TO DAY
TEMPERATURE FORECASTS HAVE ONLY MODEST CONFIDENCE AT THIS POINT.
&&
.AVIATION...27/00Z
STORY TONIGHT REMAINS WINDS AND CIGS. MVFR CIGS TO HOLD PAT FOR MUCH
OF THE NIGHT THROUGH 12Z WITH POCKETS OF VFR RETURNING AFT 12Z.
WINDS TO REMAIN STRONG...WITH GUSTS APPROACHING 40KTS AT TIMES
OVERNIGHT BEFORE 06Z...THEN SLOWLY DIMINISHING. MIXING TO CONTINUE
AFT 15Z SUN BEFORE GRADIENT RELAXES ENOUGH TO ALLOW FOR WINDS UNDER
12KTS AT 18-22Z. CIGS GIVE WAY TO SCT-FEW030-045 BY 19Z MOST AREAS
AND GO SKC TOWARD 00Z/28. WILL UPDATE TRENDS WITH NEXT PACKAGE AT
06Z./REV
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR
AUDUBON-CALHOUN-CARROLL-CASS-CRAWFORD-EMMET-PALO ALTO-POCAHONTAS-SAC.
&&
$$
SHORT TERM...SMALL
LONG TERM...JOHNSON
AVIATION...REV
AREA FORECAST DISCUSSION...UPDATED
NWS DES MOINES IA
1145 AM CST FRI NOV 25 2011
...UPDATED FOR 18Z AVIATION DISCUSSION...
.SHORT TERM /TODAY/...
STRATUS FIELD IS LIFTING THROUGH EASTERN KS AS LOW LEVEL MOISTURE
CONTINUES TO ADVECT NORTHWARD TOWARD IOWA. THE MOISTURE IS CENTERED
NEAR 950 MB. THE LATEST RUC 950 MB CONDENSATION PRESSURE DEFICITS
ARE HANDLING THE STRATUS PLACEMENT WELL AND SUGGESTS IT WILL SPREAD
NORTHEAST OVER MUCH OF CNTRL IA THIS MORNING. CIRRUS WILL ALSO BE
THICKENING OVER THE STATE TODAY AND IN COMBINATION WITH THE
STRATUS...WILL RESULT IN MOSTLY CLOUDY CONDITIONS. THIS WILL HAVE AN
IMPACT ON HIGH TEMPERATURES. READINGS AT 3 AM REMAIN QUITE MILD IN
THE MID TO UPPER 40S. ANY SUNSHINE THIS MORNING COULD QUICKLY PUSH
READINGS WELL INTO THE 50S. EXPECT CLOUDS TO BECOME PREVALENT BY MID
MORNING AND WILL LIMIT TEMPERATURES...THEREFORE HAVE TEMPERED HIGHS
FOR TODAY BACK A FEW DEGREES AND MORE INTO THE MID TO UPPER 50S.
THIS WILL BE TOO WARM IF THE STRATUS LINGERS ALL DAY.
THE INITIAL SHORT WAVE WILL REACH WESTERN IA BY THIS AFTERNOON WITH
INCREASING QG FORCING AND THE MID LEVEL DRY AIR SLOWLY ERODING AS
EVAPORATING PRECIPITATION FALLS INTO THIS LAYER. POSSIBLE BY VERY
LATE AFTERNOON THAT A FEW SPRINKLES OR LIGHT RAIN COULD REACH THE
SFC OVER THE FAR WEST CENTRAL AND SOUTHWEST. THEREFORE HAVE ADDED
LOW POPS.
.LONG TERM /TONIGHT THROUGH THURSDAY/...
FORECAST PROBLEM IN THE LONG TERM CONTINUES TO BE THE UPPER TROUGH
MOVING THROUGH THE UPPER MIDWEST THIS WEEKEND. A NORTHERN STREAM
SHORTWAVE WAS MOVING EAST THROUGH THE NORTHERN ROCKIES THIS MORNING
WHILE A WEAKER SOUTHERN STREAM WAVE WAS MOVING THROUGH THE DESERT
SOUTHWEST. THE NORTHERN SYSTEM IS FORECAST TO MOVE SOUTHEAST INTO
THE CENTRAL UNITED STATES AND DEEPEN BY SATURDAY. THE 00Z GFS/NAM
PHASE THE TWO WAVES IN THE CENTRAL STATE AND SIGNIFICANTLY DEEPEN
THE TROUGH INTO A CLOSED 500 MB LOW. THE 00Z ECMWF REMAINS
CONSISTENT WITH IT/S PREVIOUS RUN KEEPING THE SHORT WAVE ENERGY
SEPARATE. AS A RESULT...THE NORTHERN SHORTWAVE REMAINS A POSITIVE
TILTED OPEN WAVE. THE GFS/NAM SOLUTIONS HAVE A MUCH DEEPER SURFACE
LOW WHICH DEVELOPS NORTHEAST OF CENTRAL IOWA. WITH THE DEEPER
SYSTEM...THE WIND FIELDS ARE STRONG. IF THE GFS/NAM SOLUTIONS
VERIFY...AT A MINIMUM CENTRAL IOWA SHOULD HAVE A DECENT WIND EVENT
AND SOME LIGHT SNOW DUE TO THE STRONGER FORCING. IF THE WEAKER
LOOKING ECMWF VERIFIES...IT WOULD BE WINDY...BUT PROBABLY BELOW
ADVISORY CRITERIA AND LESS SNOW CHANCES. BASED THE FORECAST ON A
COMPROMISE BETWEEN THESE VARIED SOLUTIONS. NO HEADLINES FOR WIND AT
THIS POINT...BUT WILL MENTION WINDY CONDITIONS IN THE HWO. WILL
ALSO MENTION THE POSSIBILITY OF LIGHT SNOW...ESPECIALLY NORTH...BUT
ACCUMULATIONS SHOULD BE LIGHT.
MOISTURE STEAMING NORTHEAST AHEAD OF THE FRONT TONIGHT ALONG WITH A
LARGE AREA OF UPWARD FORCING AHEAD OF THE UPPER TROUGH SUPPORTS HIGH
POPS FOR RAIN TONIGHT.
ANOTHER COLD FRONT SHOULD MOVE THROUGH THE STATE LATE MONDAY. LACK
OF SIGNIFICANT FORCING AND MOISTURE SHOULD KEEP IT DRY. THE 00Z
ECMWF IS ADVERTISING A STRONGER COLD FRONT LATE NEXT WEEK.
CONFIDENCE ON THE TIMING OF THE FRONTS IS LOW DUE TO MODEL
DIFFERENCES NEXT WEEK BETWEEN THE ECMWF AND THE OPERATIONAL GFS.
&&
.AVIATION...25/18Z
STRATUS SHIELD HAS ADVANCED TO EVERYWHERE ACROSS THE TAF FORECAST
AREA AND WILL REMAIN IN PLACE THROUGH THE FORECAST PERIOD. CIGS MAY
VACILLATE BETWEEN 008 AND 015 THROUGH 00Z BUT NO PCPN EXPECTED.
AFT 00Z UPPER LEVEL LOW PRESSURE ACROSS THE HIGH PLAINS WILL ADVANCE
EAST WHILE A COLD FRONT AT THE SURFACE ENTERS FROM THE WEST. RAIN
WILL BEGIN BETWEEN 03Z AND 06Z THEN ADVANCE EAST OVERNIGHT. THE COLD
FRONT WILL BE EAST OF THE TAF LOCATIONS BY 15Z SAT AND WE WILL
LIKELY SEE FALLING TEMPS AFTER THAT TIME BUT TEMPS SHOULD REMAIN
WARM ENOUGH THROUGH 18Z FOR REMAINING PRECIP TO STAY AS RAIN.
BEYOND THE FCST PD...PRECIP WILL CHANGE OVER TO A MIX AND THEN LIGHT
SNOW AFT 18Z. A NORTHWEST WIND WILL ALSO BE ON THE INCREASE AFT 12Z
AS THE COLD AIR MOVING IN DEEPENS.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...DONAVON
LONG TERM...JOHNSON
AVIATION...FAB
AREA FORECAST DISCUSSION
NWS DES MOINES IA
552 AM CST FRI NOV 25 2011
...UPDATED FOR 12Z AVIATION DISCUSSION...
.SHORT TERM /TODAY/...
STRATUS FIELD IS LIFTING THROUGH EASTERN KS AS LOW LEVEL MOISTURE
CONTINUES TO ADVECT NORTHWARD TOWARD IOWA. THE MOISTURE IS CENTERED
NEAR 950 MB. THE LATEST RUC 950 MB CONDENSATION PRESSURE DEFICITS
ARE HANDLING THE STRATUS PLACEMENT WELL AND SUGGESTS IT WILL SPREAD
NORTHEAST OVER MUCH OF CNTRL IA THIS MORNING. CIRRUS WILL ALSO BE
THICKENING OVER THE STATE TODAY AND IN COMBINATION WITH THE
STRATUS...WILL RESULT IN MOSTLY CLOUDY CONDITIONS. THIS WILL HAVE AN
IMPACT ON HIGH TEMPERATURES. READINGS AT 3 AM REMAIN QUITE MILD IN
THE MID TO UPPER 40S. ANY SUNSHINE THIS MORNING COULD QUICKLY PUSH
READINGS WELL INTO THE 50S. EXPECT CLOUDS TO BECOME PREVALENT BY MID
MORNING AND WILL LIMIT TEMPERATURES...THEREFORE HAVE TEMPERED HIGHS
FOR TODAY BACK A FEW DEGREES AND MORE INTO THE MID TO UPPER 50S.
THIS WILL BE TOO WARM IF THE STRATUS LINGERS ALL DAY.
THE INITIAL SHORT WAVE WILL REACH WESTERN IA BY THIS AFTERNOON WITH
INCREASING QG FORCING AND THE MID LEVEL DRY AIR SLOWLY ERODING AS
EVAPORATING PRECIPITATION FALLS INTO THIS LAYER. POSSIBLE BY VERY
LATE AFTERNOON THAT A FEW SPRINKLES OR LIGHT RAIN COULD REACH THE
SFC OVER THE FAR WEST CENTRAL AND SOUTHWEST. THEREFORE HAVE ADDED
LOW POPS.
.LONG TERM /FRIDAY THROUGH THURSDAY/...
FORECAST PROBLEM IN THE LONG TERM CONTINUES TO BE THE UPPER TROUGH
MOVING THROUGH THE UPPER MIDWEST THIS WEEKEND. A NORTHERN STREAM
SHORTWAVE WAS MOVING EAST THROUGH THE NORTHERN ROCKIES THIS MORNING
WHILE A WEAKER SOUTHERN STREAM WAVE WAS MOVING THROUGH THE DESERT
SOUTHWEST. THE NORTHERN SYSTEM IS FORECAST TO MOVE SOUTHEAST INTO
THE CENTRAL UNITED STATES AND DEEPEN BY SATURDAY. THE 00Z GFS/NAM
PHASE THE TWO WAVES IN THE CENTRAL STATE AND SIGNIFICANTLY DEEPEN
THE TROUGH INTO A CLOSED 500 MB LOW. THE 00Z ECMWF REMAINS
CONSISTENT WITH IT/S PREVIOUS RUN KEEPING THE SHORT WAVE ENERGY
SEPARATE. AS A RESULT...THE NORTHERN SHORTWAVE REMAINS A POSITIVE
TILTED OPEN WAVE. THE GFS/NAM SOLUTIONS HAVE A MUCH DEEPER SURFACE
LOW WHICH DEVELOPS NORTHEAST OF CENTRAL IOWA. WITH THE DEEPER
SYSTEM...THE WIND FIELDS ARE STRONG. IF THE GFS/NAM SOLUTIONS
VERIFY...AT A MINIMUM CENTRAL IOWA SHOULD HAVE A DECENT WIND EVENT
AND SOME LIGHT SNOW DUE TO THE STRONGER FORCING. IF THE WEAKER
LOOKING ECMWF VERIFIES...IT WOULD BE WINDY...BUT PROBABLY BELOW
ADVISORY CRITERIA AND LESS SNOW CHANCES. BASED THE FORECAST ON A
COMPROMISE BETWEEN THESE VARIED SOLUTIONS. NO HEADLINES FOR WIND AT
THIS POINT...BUT WILL MENTION WINDY CONDITIONS IN THE HWO. WILL
ALSO MENTION THE POSSIBILITY OF LIGHT SNOW...ESPECIALLY NORTH...BUT
ACCUMULATIONS SHOULD BE LIGHT.
MOISTURE STEAMING NORTHEAST AHEAD OF THE FRONT TONIGHT ALONG WITH A
LARGE AREA OF UPWARD FORCING AHEAD OF THE UPPER TROUGH SUPPORTS HIGH
POPS FOR RAIN TONIGHT.
ANOTHER COLD FRONT SHOULD MOVE THROUGH THE STATE LATE MONDAY. LACK
OF SIGNIFICANT FORCING AND MOISTURE SHOULD KEEP IT DRY. THE 00Z
ECMWF IS ADVERTISING A STRONGER COLD FRONT LATE NEXT WEEK.
CONFIDENCE ON THE TIMING OF THE FRONTS IS LOW DUE TO MODEL
DIFFERENCES NEXT WEEK BETWEEN THE ECMWF AND THE OPERATIONAL GFS.
&&
.AVIATION...25/12Z
MVFR TO IFR STRATUS HAS BEEN RAPIDLY ADVANCING NORTHEAST THROUGH
EASTERN KANSAS OVERNIGHT. THIS BAND SHOULD OVERSPREAD ALL SITES
THROUGH 15Z. SOME UNCERTAINTY IF THE STRATUS WILL MAINTAIN THROUGH
THE AFTERNOON ESPECIALLY OVER THE WRN AND SRN SITES. HAVE OPTED TO
HOLD IT THROUGH THE DAY. EVEN IF IT BREAKS...THE STRATUS SHOULD
REDEVELOP EARLY THIS EVENING. RAIN SHOULD DEVELOP OVERNIGHT AS WELL.
A COLD FRONT WILL ARRIVE THROUGH THE WESTERN SITES AFTER 09Z
BRINGING GUSTY NORTHWEST WINDS.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...DONAVON
LONG TERM...JOHNSON
AVIATION...DONAVON
AREA FORECAST DISCUSSION
NWS DES MOINES IA
315 AM CST FRI NOV 25 2011
...UPDATED FOR 06Z AVIATION DISCUSSION...
.SHORT TERM /TODAY/...
STRATUS FIELD IS LIFTING THROUGH EASTERN KS AS LOW LEVEL MOISTURE
CONTINUES TO ADVECT NORTHWARD TOWARD IOWA. THE MOISTURE IS CENTERED
NEAR 950 MB. THE LATEST RUC 950 MB CONDENSATION PRESSURE DEFICITS
ARE HANDLING THE STRATUS PLACEMENT WELL AND SUGGESTS IT WILL SPREAD
NORTHEAST OVER MUCH OF CNTRL IA THIS MORNING. CIRRUS WILL ALSO BE
THICKENING OVER THE STATE TODAY AND IN COMBINATION WITH THE
STRATUS...WILL RESULT IN MOSTLY CLOUDY CONDITIONS. THIS WILL HAVE AN
IMPACT ON HIGH TEMPERATURES. READINGS AT 3 AM REMAIN QUITE MILD IN
THE MID TO UPPER 40S. ANY SUNSHINE THIS MORNING COULD QUICKLY PUSH
READINGS WELL INTO THE 50S. EXPECT CLOUDS TO BECOME PREVALENT BY MID
MORNING AND WILL LIMIT TEMPERATURES...THEREFORE HAVE TEMPERED HIGHS
FOR TODAY BACK A FEW DEGREES AND MORE INTO THE MID TO UPPER 50S.
THIS WILL BE TOO WARM IF THE STRATUS LINGERS ALL DAY.
THE INITIAL SHORT WAVE WILL REACH WESTERN IA BY THIS AFTERNOON WITH
INCREASING QG FORCING AND THE MID LEVEL DRY AIR SLOWLY ERODING AS
EVAPORATING PRECIPITATION FALLS INTO THIS LAYER. POSSIBLE BY VERY
LATE AFTERNOON THAT A FEW SPRINKLES OR LIGHT RAIN COULD REACH THE
SFC OVER THE FAR WEST CENTRAL AND SOUTHWEST. THEREFORE HAVE ADDED
LOW POPS.
.LONG TERM /FRIDAY THROUGH THURSDAY/...
FORECAST PROBLEM IN THE LONG TERM CONTINUES TO BE THE UPPER TROUGH
MOVING THROUGH THE UPPER MIDWEST THIS WEEKEND. A NORTHERN STREAM
SHORTWAVE WAS MOVING EAST THROUGH THE NORTHERN ROCKIES THIS MORNING
WHILE A WEAKER SOUTHERN STREAM WAVE WAS MOVING THROUGH THE DESERT
SOUTHWEST. THE NORTHERN SYSTEM IS FORECAST TO MOVE SOUTHEAST INTO
THE CENTRAL UNITED STATES AND DEEPEN BY SATURDAY. THE 00Z GFS/NAM
PHASE THE TWO WAVES IN THE CENTRAL STATE AND SIGNIFICANTLY DEEPEN
THE TROUGH INTO A CLOSED 500 MB LOW. THE 00Z ECMWF REMAINS
CONSISTENT WITH IT/S PREVIOUS RUN KEEPING THE SHORT WAVE ENERGY
SEPARATE. AS A RESULT...THE NORTHERN SHORTWAVE REMAINS A POSITIVE
TILTED OPEN WAVE. THE GFS/NAM SOLUTIONS HAVE A MUCH DEEPER SURFACE
LOW WHICH DEVELOPS NORTHEAST OF CENTRAL IOWA. WITH THE DEEPER
SYSTEM...THE WIND FIELDS ARE STRONG. IF THE GFS/NAM SOLUTIONS
VERIFY...AT A MINIMUM CENTRAL IOWA SHOULD HAVE A DECENT WIND EVENT
AND SOME LIGHT SNOW DUE TO THE STRONGER FORCING. IF THE WEAKER
LOOKING ECMWF VERIFIES...IT WOULD BE WINDY...BUT PROBABLY BELOW
ADVISORY CRITERIA AND LESS SNOW CHANCES. BASED THE FORECAST ON A
COMPROMISE BETWEEN THESE VARIED SOLUTIONS. NO HEADLINES FOR WIND AT
THIS POINT...BUT WILL MENTION WINDY CONDITIONS IN THE HWO. WILL
ALSO MENTION THE POSSIBILITY OF LIGHT SNOW...ESPECIALLY NORTH...BUT
ACCUMULATIONS SHOULD BE LIGHT.
MOISTURE STEAMING NORTHEAST AHEAD OF THE FRONT TONIGHT ALONG WITH A
LARGE AREA OF UPWARD FORCING AHEAD OF THE UPPER TROUGH SUPPORTS HIGH
POPS FOR RAIN TONIGHT.
ANOTHER COLD FRONT SHOULD MOVE THROUGH THE STATE LATE MONDAY. LACK
OF SIGNIFICANT FORCING AND MOISTURE SHOULD KEEP IT DRY. THE 00Z
ECMWF IS ADVERTISING A STRONGER COLD FRONT LATE NEXT WEEK.
CONFIDENCE ON THE TIMING OF THE FRONTS IS LOW DUE TO MODEL
DIFFERENCES NEXT WEEK BETWEEN THE ECMWF AND THE OPERATIONAL GFS.
&&
.AVIATION...25/06Z
STRONG SOUTHERLY FLOW WILL CONTINUE OVERNIGHT INTO FRIDAY AHEAD OF
APPROACHING SYSTEM. MOISTURE ADVECTING NORTHWARD IN LOW LEVEL JET
WILL ARRIVE IN IOWA TOWARD DAYBREAK WITH 950-900MB CDEFS DROPPING
QUICKLY. HAVE INCLUDED BROKEN STRATUS IN MOST TAFS BETWEEN 11Z AND
13Z WITH THE RAPID NORTHWARD EXPANSION. THE STATUS SHOULD PERSIST
FOR MUCH OF THE MORNING BUT MAY SEE SOME BREAKUP TOWARD AFTERNOON
WITH SOME HEATING...ALTHOUGH THE MAY BE OPTIMISTIC GIVEN THE CLIMO
THIS TIME OF YEAR. NEXT CONCERN WOULD BE WITH THE DEVELOPMENT OF
RAINFALL FRIDAY EVENING AS FRONT ENTERS THE STATE AND LARGE SCALE
ASCENT INCREASES.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...DONAVON
LONG TERM...JOHNSON
AVIATION...COGIL
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1251 PM EST FRI NOV 25 2011
UPDATED AVIATION DISCUSSION FOR 18Z TAFS
.SYNOPSIS...
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW PERSISTENT UPR
RDGING IN PLACE OVER NAMERICA DOWNSTREAM OF TROFFING OVER THE PAC NW
AND WRN CAN. CLOSER TO THE SFC...THE UPR GRT LKS ARE DOMINATED BY A
STRONG SW FLOW BTWN HI PRES IN THE MID ATLANTIC STATES AND LO PRES
OVER NRN ONTARIO. GRAND MARAIS IN ALGER COUNTY REPORTED SW WIND
GUSTS UP TO 37 MPH AT 0330Z. THE 00Z INL AND MPX RAOBS ARE QUITE DRY
/IN FACT...THE 00Z H7 DEWPT DEPRESSION AT ABERDEEN SDAKOTA WAS
42C/...SO NOTHING BUT HI CLDS ARE PRESENT ALONG AND AHEAD OF
ATTENDANT COLD FNT EXTENDING FM THE ONTARIO LO THRU NW MN INTO
NDAKOTA. MORE EXTENSIVE LO CLDS FOLLOW THE FROPA OVER NW NDAKOTA AND
SCNTRL CAN WITH SHALLOW COLD AIR INFUSION. OVER THE E HALF OF THE
CWA...LLVL MSTR DEPICTED ON THE 00Z GRB RAOB BLO SHARP INVRN BASE
NEAR H95 HAS RESULTED IN EXTENSIVE LO CLD. OTRW TEMPS ARE WELL ABV
NORMAL FOR THE SEASON...WITH 00Z H85 TEMPS RANGING FM 13C AT GRB AND
INL TO 15C AT MPX. SFC TEPS ARE STILL WELL INTO THE 40S AT MANY
PLACES EARLY THIS MRNG...10 TO 15 DEGREES ABV THE NORMAL HI TEMPS
FOR THE DATE. WELL TO THE W... WV IMAGERY INDICATES A STRONGER
SHRTWV IS APRCHG THE PAC NW...WHERE 12Z-24Z H3 FALLS UP TO 100M
OCCURRED.
&&
.DISCUSSION...
MAIN FCST CONCERNS SHIFT FM LO CLDS/WELL ABV NORMAL TEMPS TDAY TO
PCPN CHCS TNGT THRU THE WEEKEND.
TDAY...SFC HI PRES OVER THE MID ATLANTIC IS PROGGED TO DRIFT OFF THE
SE COAST WHILE LO PRES NOW OVER NRN ONTARIO WL DRIFT ACRS QUEBEC...
DRAGGING ATTENDANT COLD FNT INTO THE CWA DURING THE AFTN. ALTHOUGH
SFC TEMPS WL BE HELD DOWN ESPECIALLY OVER THE NW WITH THE ARRIVAL OF
LLVL COLDER AIR/ARRIVAL OF MORE LO CLDS BEHIND THE FROPA...READINGS
WL STILL BE WELL ABV NORMAL...ESPECIALLY OVER THE SCNTRL WHERE THE
LO CLDS ARE MORE LIKELY TO BREAK UP. THE SW FLOW OFF LK MI THRU THE
DAY AND LO SUN ANGLE WL LIKELY RESULT IN A PERSISTENCE OF THE LO CLD
OVER THE E EVEN THOUGH THE STRONGER SW WINDS OBSVD EARLY THIS MRNG
WL DIMINISH QUICKLY AS THE PRES GRADIENT SLACKENS. ALTHOUGH SOME
MODELS GENERATE LGT PCPN OVER THE CWA WITH THE COLD FROPA...PREFER
THE DRY NAM GIVEN THE EXCESSIVE MID LVL DRYNESS OBSVD UPSTREAM.
TNGT...STRONGER SHRTWV NOW MOVING INTO THE PAC NW IS FCST TO DEEPEN
UPR TROF IN THE PLAINS...WITH SFC LO PRES DVLPG OVER NW WI ON
STALLED FNT THAT WL REMAIN ACRS THE CWA. ALTHOUGH LINGERING MID LVL
DRY AIR WL LIMIT PCPN CHCS IN THE EVNG...EXPANDING DEEP LYR QVECTOR
CNVGC/UPR DVGC/SHARPENING H85-7 FGEN ASSOCIATED WITH APRCHG SHRTWV/
EXIT REGION OF ACCOMPANYING 120KT H3 JET MAX WL INCRS RA CHCS
ESPECIALLY OVER THE SW HALF LATER. TENDED TOWARD THE SOMEWHAT WETTER
00Z GFS/12Z ECMWF GIVEN APPARENT STRENGTH OF SHRTWV NOW APRCHG THE
PAC NW.
SAT...MODEL DISCREPANCIES BECOME MORE PRONOUNCED WITH THE HANDLING
OF THE DVLPG LO...SO CONFIDENCE IN THE FCST WL DIMINISH. GIVEN
APPARENT STRENGHT OF INCOMING SHRTWV AS MENTIONED ABOVE...TENDED
TOWARD THE DEEPER 00Z NAM/GFS SCENARIOS THAT SHOW CUTOFF H5 LO
FORMING SOMEWHERE OVER THE UPR MS RIVER VALLEY/UPR MIDWEST.
HOWEVER...NCEP PREFERENCE FOR THE WEAKER SOLNS SHOWN BY THE 12Z
ECMWF AND 00Z CNDN LOWER CONFIDENCE FURTHER. FORTUNATELY...THERE IS
RELATIVELY LTL DIFFERENCE IN THE SFC LO PLACEMENT AMONG THE VARIOUS
MODELS DESPITE THE DIFFERENCES IN INTENSITY. MODELS SHOW SFC LO
MOVING TO NEAR MQT BY 00Z SUN. ALTHOUGH DRY SLOTTING TO THE E OF THE
H5 LO WL LIKELY RESULT IN A DIMINISHING TREND OF THE PCPN OVER
MAINLY THE CNTRL AND E...EXPECT HEAVIER PCPN TO LINGER OVER THE W FM
IWD-CMX THRU THE DAY CLOSER TO THE TRACK OF THE ACCOMPANYING H85 LO.
PER GFS FCST WBLB ZERO HGT FCST TO FALL NEAR 1K FT AGL BY 00Z
SUN...EXPECT ENUF COLD AIR TO ARRIVE LATE IN THE DAY TO RESULT IN AT
LEAST A MIX OF RA/SN NEAR IWD UNDER THE SHARPER CYC NLY FLOW.
SAT NGT THRU SUN...VARIOUS MODELS SHOW SFC LO DRIFTING SLOWLY TO THE
NE TO SSE OF JAMES BAY BY LATE IN THE DAY SUN. THE NAM BECOMES A
PARTICULAR OUTLIER SHOWING THE LO LINGERING NEAR UPR MI...SO
REJECTED THIS FCST. THE OTHER PREFERRED MODELS SUG PCPN WITHIN COMMA
HEAD MSTR UNDER SHARPER NNW CYC FLOW/H85 THERMAL TROFFING WL IMPACT
MAINLY THE NW HALF AND SLOWLY CHG TO SN AS COLDER AIR MOVES OVHD...
WITH BOTH THE 00Z GFS/12Z ECMWF INDICATING H85 TEMPS FALLING TO ARND
-9C...LO ENUF FOR LK EFFECT PCPN CONSIDERING LK SUP TEMPS ARND 5C.
HOWEVER...EVEN THE DEEPER GFS SUGS SN GROWTH MICROPHYSICS WL NOT BE
VERY FVRBL GIVEN FCST WEAK UVV IN THE DENDRITIC SN GROWTH ZN. EVEN
SO...SOME LO END ADVY SN AMNTS MAY BE PSBL OVER THE W WITH LK
ENHANCEMENT AS THE SN SHOULD BE WET AND HEAVY. THE NEW 00Z ECMWF
INDICATES GOOD CONTINUITY WITH THE 12Z RUN...BUT SHOWS QUICKER
DRYING ON SUN WITH A WEAKER CYC FLOW/FASTER EXIT THAN INDICATED BY
THE DEEPER GFS. TENDED TOWARD HIER POPS OVER THE W TO THE HURON MTNS
WHERE THE UPSLOPE NNW FLOW WOULD HAVE A MORE SGNFT IMPACT AS HINTED
BY THE 00Z CNDN MODEL. EXPECT A DRYING TREND W-E ON SUN NGT WITH THE
ARRIVAL OF A HI PRES RDG.
EXTENDED RANGE...EXPECT A MORE SEASONABLY CHILLY PATTERN WITH NW
FLOW ALF ALLOWING FOR FREQUENT SHRTWV PASSAGES/POTENTIAL LES
EPISODES. MADE FEW CHGS TO ALL BLEND FCST NUMBERS.
&&
.AVIATION /FOR THE 18Z TAF ISSUANCE/...
ANOTHER DIFFICULT TAF FCST. LOW CLOUDS/VSBY HAVE EXITED KSAW BUT
SHOULD RETURN BY LATE AFTN AS LOW CLOUDS OVR WI STREAM NORTHWARD.
MAY SEE YET ANOTHER NIGHT OF CONDITIONS NEAR AIRFIELD MINS BUT SINCE
ESE WINDS ARE NOT AS FAVORABLE FOR LOWER CONDITIONS...KEPT CIGS/VSBY
LIFR. AT KCMX...LOW CLOUDS HAVE JUST RECENTLY DEVELOPED AS MOISTURE
FM ONTARIO DROPS IN ON DEVELOPING N/NE WINDS. CLOUDS MAY BE MORE
VARIABLE THIS AFTN...BUT OVERALL THE PREVAILING TREND WILL BE FOR
THE LOW CLOUDS TO STICK AROUND THROUGH TONIGHT. ONCE WINDS BECOME
MORE EASTERLY...HAVE LOWERED CIGS/VSBY TO IFR OVERNIGHT TONIGHT...BUT
THIS MAY NOT BE LOW ENOUGH GIVEN FAVORABLE EAST WIND DIRECTION. AS
FOR KIWD...JUST MID-HIGH CLOUDS THUS FAR...BUT EXPECT LOWER CIGS TO
DEVELOP LATE TODAY AS THE LOW-CLOUDS IN WESTERN AND CNTRL WI PUSH
NORTHWARD. EXPECT RAIN TO DEVELOP LATE TONIGHT AT ALL THREE SITES AS
LOW PRESSURE SYSTEM LIFTS TOWARD AREA. MAINLY LIFR CONDITIONS
EXPECTED FOR ALL SITES SATURDAY MORNING...WITH ONLY SLOW IMPROVEMENT
SATURDAY AFTN. &&
.MARINE /FOR THE 4AM LAKE SUPERIOR FORECAST ISSUANCE/...
A SURFACE TROUGH STALLING OVER LAKE SUPERIOR TODAY WILL BRING A
DIMINISHING TREND TO THE WINDS THROUGH MUCH OF THE DAY. A LOW
DEVELOPING ALONG THE SURFACE TROUGH IN THE CENTRAL PLAINS
TODAY...WILL BEGIN TO MOVE NORTHEAST TONIGHT AND OVER CENTRAL UPPER
MICHIGAN ON SATURDAY. EXPECT INCREASING EAST TO NORTHEAST WINDS LATE
THIS AFTERNOON OVER THE WEST AND THE REST OVER THE AREA
TONIGHT...WITH GUSTS UP TO 30KTS OVER THE NORTH HALF OF THE LAKE
TONIGHT. AS THE LOW MOVES EAST ON SATURDAY NIGHT...NORTH GALES OF
35KTS ARE EXPECTED OVER WEST CENTRAL LAKE SUPERIOR. THE GALES SHOULD
SPREAD EAST ON SUNDAY AS WINDS SHIFT TO THE NORTHWEST...BEFORE
DIMINISHING BELOW 20KTS ON SUNDAY NIGHT AS HIGH PRESSURE MOVES OVER
LAKE SUPERIOR. A SURFACE TROUGH MOVING ACROSS LAKE SUPERIOR ON
MONDAY AFTERNOON AND EVENING WILL PROVIDE ANOTHER PERIOD OF STRONG
SOUTHWEST WINDS...WITH THE POTENTIAL OF NORTHWEST GALES TO 35KTS
BEHIND THE TROUGH MONDAY NIGHT AND TUESDAY MORNING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM SATURDAY EVENING THROUGH SUNDAY AFTERNOON FOR
LSZ263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...KC
DISCUSSION...KC
AVIATION...JLA
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
652 AM EST FRI NOV 25 2011
UPDATED AVIATION DISCUSSION FOR 12Z TAFS
.SYNOPSIS...
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW PERSISTENT UPR
RDGING IN PLACE OVER NAMERICA DOWNSTREAM OF TROFFING OVER THE PAC NW
AND WRN CAN. CLOSER TO THE SFC...THE UPR GRT LKS ARE DOMINATED BY A
STRONG SW FLOW BTWN HI PRES IN THE MID ATLANTIC STATES AND LO PRES
OVER NRN ONTARIO. GRAND MARAIS IN ALGER COUNTY REPORTED SW WIND
GUSTS UP TO 37 MPH AT 0330Z. THE 00Z INL AND MPX RAOBS ARE QUITE DRY
/IN FACT...THE 00Z H7 DEWPT DEPRESSION AT ABERDEEN SDAKOTA WAS
42C/...SO NOTHING BUT HI CLDS ARE PRESENT ALONG AND AHEAD OF
ATTENDANT COLD FNT EXTENDING FM THE ONTARIO LO THRU NW MN INTO
NDAKOTA. MORE EXTENSIVE LO CLDS FOLLOW THE FROPA OVER NW NDAKOTA AND
SCNTRL CAN WITH SHALLOW COLD AIR INFUSION. OVER THE E HALF OF THE
CWA...LLVL MSTR DEPICTED ON THE 00Z GRB RAOB BLO SHARP INVRN BASE
NEAR H95 HAS RESULTED IN EXTENSIVE LO CLD. OTRW TEMPS ARE WELL ABV
NORMAL FOR THE SEASON...WITH 00Z H85 TEMPS RANGING FM 13C AT GRB AND
INL TO 15C AT MPX. SFC TEPS ARE STILL WELL INTO THE 40S AT MANY
PLACES EARLY THIS MRNG...10 TO 15 DEGREES ABV THE NORMAL HI TEMPS
FOR THE DATE. WELL TO THE W... WV IMAGERY INDICATES A STRONGER
SHRTWV IS APRCHG THE PAC NW...WHERE 12Z-24Z H3 FALLS UP TO 100M
OCCURRED.
&&
.DISCUSSION...
MAIN FCST CONCERNS SHIFT FM LO CLDS/WELL ABV NORMAL TEMPS TDAY TO
PCPN CHCS TNGT THRU THE WEEKEND.
TDAY...SFC HI PRES OVER THE MID ATLANTIC IS PROGGED TO DRIFT OFF THE
SE COAST WHILE LO PRES NOW OVER NRN ONTARIO WL DRIFT ACRS QUEBEC...
DRAGGING ATTENDANT COLD FNT INTO THE CWA DURING THE AFTN. ALTHOUGH
SFC TEMPS WL BE HELD DOWN ESPECIALLY OVER THE NW WITH THE ARRIVAL OF
LLVL COLDER AIR/ARRIVAL OF MORE LO CLDS BEHIND THE FROPA...READINGS
WL STILL BE WELL ABV NORMAL...ESPECIALLY OVER THE SCNTRL WHERE THE
LO CLDS ARE MORE LIKELY TO BREAK UP. THE SW FLOW OFF LK MI THRU THE
DAY AND LO SUN ANGLE WL LIKELY RESULT IN A PERSISTENCE OF THE LO CLD
OVER THE E EVEN THOUGH THE STRONGER SW WINDS OBSVD EARLY THIS MRNG
WL DIMINISH QUICKLY AS THE PRES GRADIENT SLACKENS. ALTHOUGH SOME
MODELS GENERATE LGT PCPN OVER THE CWA WITH THE COLD FROPA...PREFER
THE DRY NAM GIVEN THE EXCESSIVE MID LVL DRYNESS OBSVD UPSTREAM.
TNGT...STRONGER SHRTWV NOW MOVING INTO THE PAC NW IS FCST TO DEEPEN
UPR TROF IN THE PLAINS...WITH SFC LO PRES DVLPG OVER NW WI ON
STALLED FNT THAT WL REMAIN ACRS THE CWA. ALTHOUGH LINGERING MID LVL
DRY AIR WL LIMIT PCPN CHCS IN THE EVNG...EXPANDING DEEP LYR QVECTOR
CNVGC/UPR DVGC/SHARPENING H85-7 FGEN ASSOCIATED WITH APRCHG SHRTWV/
EXIT REGION OF ACCOMPANYING 120KT H3 JET MAX WL INCRS RA CHCS
ESPECIALLY OVER THE SW HALF LATER. TENDED TOWARD THE SOMEWHAT WETTER
00Z GFS/12Z ECMWF GIVEN APPARENT STRENGTH OF SHRTWV NOW APRCHG THE
PAC NW.
SAT...MODEL DISCREPANCIES BECOME MORE PRONOUNCED WITH THE HANDLING
OF THE DVLPG LO...SO CONFIDENCE IN THE FCST WL DIMINISH. GIVEN
APPARENT STRENGHT OF INCOMING SHRTWV AS MENTIONED ABOVE...TENDED
TOWARD THE DEEPER 00Z NAM/GFS SCENARIOS THAT SHOW CUTOFF H5 LO
FORMING SOMEWHERE OVER THE UPR MS RIVER VALLEY/UPR MIDWEST.
HOWEVER...NCEP PREFERENCE FOR THE WEAKER SOLNS SHOWN BY THE 12Z
ECMWF AND 00Z CNDN LOWER CONFIDENCE FURTHER. FORTUNATELY...THERE IS
RELATIVELY LTL DIFFERENCE IN THE SFC LO PLACEMENT AMONG THE VARIOUS
MODELS DESPITE THE DIFFERENCES IN INTENSITY. MODELS SHOW SFC LO
MOVING TO NEAR MQT BY 00Z SUN. ALTHOUGH DRY SLOTTING TO THE E OF THE
H5 LO WL LIKELY RESULT IN A DIMINISHING TREND OF THE PCPN OVER
MAINLY THE CNTRL AND E...EXPECT HEAVIER PCPN TO LINGER OVER THE W FM
IWD-CMX THRU THE DAY CLOSER TO THE TRACK OF THE ACCOMPANYING H85 LO.
PER GFS FCST WBLB ZERO HGT FCST TO FALL NEAR 1K FT AGL BY 00Z
SUN...EXPECT ENUF COLD AIR TO ARRIVE LATE IN THE DAY TO RESULT IN AT
LEAST A MIX OF RA/SN NEAR IWD UNDER THE SHARPER CYC NLY FLOW.
SAT NGT THRU SUN...VARIOUS MODELS SHOW SFC LO DRIFTING SLOWLY TO THE
NE TO SSE OF JAMES BAY BY LATE IN THE DAY SUN. THE NAM BECOMES A
PARTICULAR OUTLIER SHOWING THE LO LINGERING NEAR UPR MI...SO
REJECTED THIS FCST. THE OTHER PREFERRED MODELS SUG PCPN WITHIN COMMA
HEAD MSTR UNDER SHARPER NNW CYC FLOW/H85 THERMAL TROFFING WL IMPACT
MAINLY THE NW HALF AND SLOWLY CHG TO SN AS COLDER AIR MOVES OVHD...
WITH BOTH THE 00Z GFS/12Z ECMWF INDICATING H85 TEMPS FALLING TO ARND
-9C...LO ENUF FOR LK EFFECT PCPN CONSIDERING LK SUP TEMPS ARND 5C.
HOWEVER...EVEN THE DEEPER GFS SUGS SN GROWTH MICROPHYSICS WL NOT BE
VERY FVRBL GIVEN FCST WEAK UVV IN THE DENDRITIC SN GROWTH ZN. EVEN
SO...SOME LO END ADVY SN AMNTS MAY BE PSBL OVER THE W WITH LK
ENHANCEMENT AS THE SN SHOULD BE WET AND HEAVY. THE NEW 00Z ECMWF
INDICATES GOOD CONTINUITY WITH THE 12Z RUN...BUT SHOWS QUICKER
DRYING ON SUN WITH A WEAKER CYC FLOW/FASTER EXIT THAN INDICATED BY
THE DEEPER GFS. TENDED TOWARD HIER POPS OVER THE W TO THE HURON MTNS
WHERE THE UPSLOPE NNW FLOW WOULD HAVE A MORE SGNFT IMPACT AS HINTED
BY THE 00Z CNDN MODEL. EXPECT A DRYING TREND W-E ON SUN NGT WITH THE
ARRIVAL OF A HI PRES RDG.
EXTENDED RANGE...EXPECT A MORE SEASONABLY CHILLY PATTERN WITH NW
FLOW ALF ALLOWING FOR FREQUENT SHRTWV PASSAGES/POTENTIAL LES
EPISODES. MADE FEW CHGS TO ALL BLEND FCST NUMBERS.
&&
.AVIATION /FOR THE 12Z TAF ISSUANCE/...
ANOTHER DIFFICULT TAF FORECAST...AS LOW CLOUDS HAVE SPREAD OVER
CENTRAL AND EASTERN UPPER MICHIGAN. WITH THE LIGHT UPSLOPE FLOW AT
KSAW...EXPECT THE VLIFR CIGS/VSBYS TO CONTINUE THROUGH THE MORNING.
DIURNAL TRENDS WILL TRY TO RAISE CIGS...BUT WITH WINDS WEAKENING
THROUGH THE DAY...HAVE A TOUGH TIME BELIEVING THEY WILL EXIT LIKE
YESTERDAY. AS FOR KIWD/KCMX...EXPECT JUST HIGH CLOUDS TO AFFECT BOTH
SITES THIS MORNING. LIMITED CONFIDENCE ON MVFR CIGS MOVING IN...BUT
THINK IT WILL BE IN THE AFTN WITH SFC TROUGH PUSHING THROUGH. ALL
SITES SHOULD SEE LOWERING CIGS/VSBYS DURING THE NIGHT...WITH -RA AT
KIWD/KCMX...AS A LOW PRESSURE SYSTEM APPROACHES.
&&
.MARINE /FOR THE 4AM LAKE SUPERIOR FORECAST ISSUANCE/...
A SURFACE TROUGH STALLING OVER LAKE SUPERIOR TODAY WILL BRING A
DIMINISHING TREND TO THE WINDS THROUGH MUCH OF THE DAY. A LOW
DEVELOPING ALONG THE SURFACE TROUGH IN THE CENTRAL PLAINS
TODAY...WILL BEGIN TO MOVE NORTHEAST TONIGHT AND OVER CENTRAL UPPER
MICHIGAN ON SATURDAY. EXPECT INCREASING EAST TO NORTHEAST WINDS LATE
THIS AFTERNOON OVER THE WEST AND THE REST OVER THE AREA
TONIGHT...WITH GUSTS UP TO 30KTS OVER THE NORTH HALF OF THE LAKE
TONIGHT. AS THE LOW MOVES EAST ON SATURDAY NIGHT...NORTH GALES OF
35KTS ARE EXPECTED OVER WEST CENTRAL LAKE SUPERIOR. THE GALES SHOULD
SPREAD EAST ON SUNDAY AS WINDS SHIFT TO THE NORTHWEST...BEFORE
DIMINISHING BELOW 20KTS ON SUNDAY NIGHT AS HIGH PRESSURE MOVES OVER
LAKE SUPERIOR. A SURFACE TROUGH MOVING ACROSS LAKE SUPERIOR ON
MONDAY AFTERNOON AND EVENING WILL PROVIDE ANOTHER PERIOD OF STRONG
SOUTHWEST WINDS...WITH THE POTENTIAL OF NORTHWEST GALES TO 35KTS
BEHIND THE TROUGH MONDAY NIGHT AND TUESDAY MORNING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM SATURDAY EVENING THROUGH SUNDAY AFTERNOON FOR
LSZ263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...KC
DISCUSSION...KC
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
405 AM EST FRI NOV 25 2011
.SYNOPSIS...
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW PERSISTENT UPR
RDGING IN PLACE OVER NAMERICA DOWNSTREAM OF TROFFING OVER THE PAC NW
AND WRN CAN. CLOSER TO THE SFC...THE UPR GRT LKS ARE DOMINATED BY A
STRONG SW FLOW BTWN HI PRES IN THE MID ATLANTIC STATES AND LO PRES
OVER NRN ONTARIO. GRAND MARAIS IN ALGER COUNTY REPORTED SW WIND
GUSTS UP TO 37 MPH AT 0330Z. THE 00Z INL AND MPX RAOBS ARE QUITE DRY
/IN FACT...THE 00Z H7 DEWPT DEPRESSION AT ABERDEEN SDAKOTA WAS
42C/...SO NOTHING BUT HI CLDS ARE PRESENT ALONG AND AHEAD OF
ATTENDANT COLD FNT EXTENDING FM THE ONTARIO LO THRU NW MN INTO
NDAKOTA. MORE EXTENSIVE LO CLDS FOLLOW THE FROPA OVER NW NDAKOTA AND
SCNTRL CAN WITH SHALLOW COLD AIR INFUSION. OVER THE E HALF OF THE
CWA...LLVL MSTR DEPICTED ON THE 00Z GRB RAOB BLO SHARP INVRN BASE
NEAR H95 HAS RESULTED IN EXTENSIVE LO CLD. OTRW TEMPS ARE WELL ABV
NORMAL FOR THE SEASON...WITH 00Z H85 TEMPS RANGING FM 13C AT GRB AND
INL TO 15C AT MPX. SFC TEPS ARE STILL WELL INTO THE 40S AT MANY
PLACES EARLY THIS MRNG...10 TO 15 DEGREES ABV THE NORMAL HI TEMPS
FOR THE DATE. WELL TO THE W... WV IMAGERY INDICATES A STRONGER
SHRTWV IS APRCHG THE PAC NW...WHERE 12Z-24Z H3 FALLS UP TO 100M
OCCURRED.
&&
.DISCUSSION...
MAIN FCST CONCERNS SHIFT FM LO CLDS/WELL ABV NORMAL TEMPS TDAY TO
PCPN CHCS TNGT THRU THE WEEKEND.
TDAY...SFC HI PRES OVER THE MID ATLANTIC IS PROGGED TO DRIFT OFF THE
SE COAST WHILE LO PRES NOW OVER NRN ONTARIO WL DRIFT ACRS QUEBEC...
DRAGGING ATTENDANT COLD FNT INTO THE CWA DURING THE AFTN. ALTHOUGH
SFC TEMPS WL BE HELD DOWN ESPECIALLY OVER THE NW WITH THE ARRIVAL OF
LLVL COLDER AIR/ARRIVAL OF MORE LO CLDS BEHIND THE FROPA...READINGS
WL STILL BE WELL ABV NORMAL...ESPECIALLY OVER THE SCNTRL WHERE THE
LO CLDS ARE MORE LIKELY TO BREAK UP. THE SW FLOW OFF LK MI THRU THE
DAY AND LO SUN ANGLE WL LIKELY RESULT IN A PERSISTENCE OF THE LO CLD
OVER THE E EVEN THOUGH THE STRONGER SW WINDS OBSVD EARLY THIS MRNG
WL DIMINISH QUICKLY AS THE PRES GRADIENT SLACKENS. ALTHOUGH SOME
MODELS GENERATE LGT PCPN OVER THE CWA WITH THE COLD FROPA...PREFER
THE DRY NAM GIVEN THE EXCESSIVE MID LVL DRYNESS OBSVD UPSTREAM.
TNGT...STRONGER SHRTWV NOW MOVING INTO THE PAC NW IS FCST TO DEEPEN
UPR TROF IN THE PLAINS...WITH SFC LO PRES DVLPG OVER NW WI ON
STALLED FNT THAT WL REMAIN ACRS THE CWA. ALTHOUGH LINGERING MID LVL
DRY AIR WL LIMIT PCPN CHCS IN THE EVNG...EXPANDING DEEP LYR QVECTOR
CNVGC/UPR DVGC/SHARPENING H85-7 FGEN ASSOCIATED WITH APRCHG SHRTWV/
EXIT REGION OF ACCOMPANYING 120KT H3 JET MAX WL INCRS RA CHCS
ESPECIALLY OVER THE SW HALF LATER. TENDED TOWARD THE SOMEWHAT WETTER
00Z GFS/12Z ECMWF GIVEN APPARENT STRENGTH OF SHRTWV NOW APRCHG THE
PAC NW.
SAT...MODEL DISCREPANCIES BECOME MORE PRONOUNCED WITH THE HANDLING
OF THE DVLPG LO...SO CONFIDENCE IN THE FCST WL DIMINISH. GIVEN
APPARENT STRENGHT OF INCOMING SHRTWV AS MENTIONED ABOVE...TENDED
TOWARD THE DEEPER 00Z NAM/GFS SCENARIOS THAT SHOW CUTOFF H5 LO
FORMING SOMEWHERE OVER THE UPR MS RIVER VALLEY/UPR MIDWEST.
HOWEVER...NCEP PREFERENCE FOR THE WEAKER SOLNS SHOWN BY THE 12Z
ECMWF AND 00Z CNDN LOWER CONFIDENCE FURTHER. FORTUNATELY...THERE IS
RELATIVELY LTL DIFFERENCE IN THE SFC LO PLACEMENT AMONG THE VARIOUS
MODELS DESPITE THE DIFFERENCES IN INTENSITY. MODELS SHOW SFC LO
MOVING TO NEAR MQT BY 00Z SUN. ALTHOUGH DRY SLOTTING TO THE E OF THE
H5 LO WL LIKELY RESULT IN A DIMINISHING TREND OF THE PCPN OVER
MAINLY THE CNTRL AND E...EXPECT HEAVIER PCPN TO LINGER OVER THE W FM
IWD-CMX THRU THE DAY CLOSER TO THE TRACK OF THE ACCOMPANYING H85 LO.
PER GFS FCST WBLB ZERO HGT FCST TO FALL NEAR 1K FT AGL BY 00Z
SUN...EXPECT ENUF COLD AIR TO ARRIVE LATE IN THE DAY TO RESULT IN AT
LEAST A MIX OF RA/SN NEAR IWD UNDER THE SHARPER CYC NLY FLOW.
SAT NGT THRU SUN...VARIOUS MODELS SHOW SFC LO DRIFTING SLOWLY TO THE
NE TO SSE OF JAMES BAY BY LATE IN THE DAY SUN. THE NAM BECOMES A
PARTICULAR OUTLIER SHOWING THE LO LINGERING NEAR UPR MI...SO
REJECTED THIS FCST. THE OTHER PREFERRED MODELS SUG PCPN WITHIN COMMA
HEAD MSTR UNDER SHARPER NNW CYC FLOW/H85 THERMAL TROFFING WL IMPACT
MAINLY THE NW HALF AND SLOWLY CHG TO SN AS COLDER AIR MOVES OVHD...
WITH BOTH THE 00Z GFS/12Z ECMWF INDICATING H85 TEMPS FALLING TO ARND
-9C...LO ENUF FOR LK EFFECT PCPN CONSIDERING LK SUP TEMPS ARND 5C.
HOWEVER...EVEN THE DEEPER GFS SUGS SN GROWTH MICROPHYSICS WL NOT BE
VERY FVRBL GIVEN FCST WEAK UVV IN THE DENDRITIC SN GROWTH ZN. EVEN
SO...SOME LO END ADVY SN AMNTS MAY BE PSBL OVER THE W WITH LK
ENHANCEMENT AS THE SN SHOULD BE WET AND HEAVY. THE NEW 00Z ECMWF
INDICATES GOOD CONTINUITY WITH THE 12Z RUN...BUT SHOWS QUICKER
DRYING ON SUN WITH A WEAKER CYC FLOW/FASTER EXIT THAN INDICATED BY
THE DEEPER GFS. TENDED TOWARD HIER POPS OVER THE W TO THE HURON MTNS
WHERE THE UPSLOPE NNW FLOW WOULD HAVE A MORE SGNFT IMPACT AS HINTED
BY THE 00Z CNDN MODEL. EXPECT A DRYING TREND W-E ON SUN NGT WITH THE
ARRIVAL OF A HI PRES RDG.
EXTENDED RANGE...EXPECT A MORE SEASONABLY CHILLY PATTERN WITH NW
FLOW ALF ALLOWING FOR FREQUENT SHRTWV PASSAGES/POTENTIAL LES
EPISODES. MADE FEW CHGS TO ALL BLEND FCST NUMBERS.
&&
.AVIATION /FOR THE 06Z TAF ISSUANCE/...
IR SATELLITE IMAGERY SHOWS STRATUS/FOG EXPANDING FROM ERN UPR MI
INTO CENTRAL UPR MI THIS EVENING AS LOW-LVL MOISTURE BCMS TRAPPED
UNDER STRENGTHENING INVERSION. KSAW HAS ALREADY GOTTEN INTO STRATUS
AND PATCHY FOG AND WOULD EXPECT THIS TO LINGER INTO THE LATE MORNING
AS SOUTHWEST WINDS PUSH MOISTURE BACK INTO THE REGION TONIGHT AND
INVERSION STRENGTHENS...EXPECT LOW CLOUDS TO REDEVELOP AND PUSH INTO
THE TAF SITES. GREATEST CHANCE OF LOW CLOUDS FORMING TONIGHT WILL BE
AT KSAW...BUT THERE SHOULD BE IFR/LOWER MVFR CLOUDS AT ALL SITES BY
MID MORNING ON FRIDAY. LLWS IS EXPECTED AGAIN TONIGHT AHEAD OF AN
APPROACHING SURFACE TROUGH THAT MOVES THROUGH ON FRIDAY.
&&
.MARINE /FOR THE 4AM LAKE SUPERIOR FORECAST ISSUANCE/...
A SURFACE TROUGH STALLING OVER LAKE SUPERIOR TODAY WILL BRING A
DIMINISHING TREND TO THE WINDS THROUGH MUCH OF THE DAY. A LOW
DEVELOPING ALONG THE SURFACE TROUGH IN THE CENTRAL PLAINS
TODAY...WILL BEGIN TO MOVE NORTHEAST TONIGHT AND OVER CENTRAL UPPER
MICHIGAN ON SATURDAY. EXPECT INCREASING EAST TO NORTHEAST WINDS LATE
THIS AFTERNOON OVER THE WEST AND THE REST OVER THE AREA
TONIGHT...WITH GUSTS UP TO 30KTS OVER THE NORTH HALF OF THE LAKE
TONIGHT. AS THE LOW MOVES EAST ON SATURDAY NIGHT...NORTH GALES OF
35KTS ARE EXPECTED OVER WEST CENTRAL LAKE SUPERIOR. THE GALES SHOULD
SPREAD EAST ON SUNDAY AS WINDS SHIFT TO THE NORTHWEST...BEFORE
DIMINISHING BELOW 20KTS ON SUNDAY NIGHT AS HIGH PRESSURE MOVES OVER
LAKE SUPERIOR. A SURFACE TROUGH MOVING ACROSS LAKE SUPERIOR ON
MONDAY AFTERNOON AND EVENING WILL PROVIDE ANOTHER PERIOD OF STRONG
SOUTHWEST WINDS...WITH THE POTENTIAL OF NORTHWEST GALES TO 35KTS
BEHIND THE TROUGH MONDAY NIGHT AND TUESDAY MORNING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM SATURDAY EVENING THROUGH SUNDAY AFTERNOON FOR
LSZ263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...KC
DISCUSSION...KC
AVIATION...VOSS
MARINE...SRF
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
254 PM MST FRI NOV 25 2011
.DISCUSSION...
VERY DRY COLD AIR ADVECTION IS TAKING HOLD OF THE REGION LATE THIS
AFTERNOON BEHIND OUR THANKSGIVING STORM SYSTEM. A THIN BAND OF
RAIN AND STORMS IS LINGERING ALONG THE PACIFIC FRONTAL BNDRY OVER
THE EAST CENTRAL PLAINS. ANOTHER AREA OF RAIN/SNOW IS SLIDING
EAST ACROSS THE NE PLAINS ALONG AND BEHIND THE HIGH PLAINS COLD
FRONT. REMOVED POPS FROM ALL AREAS EXCEPT THE NE PLAINS WHERE THE
GFS...EURO AND RUC HOLD ON TO SOME QPF THROUGH 11PM. OTHERWISE...
WINDS WILL BE ON THE BREEZY SIDE THROUGH THE EVENING ACROSS THE
STATE AS LAMINAR NW FLOW REMAINS FIRMLY IN PLACE.
THE MEDIUM RANGE FORECAST THROUGH MONDAY WILL BE TRANQUIL AND
COOL WITH LIGHT WINDS AND MOSTLY CLEAR SKIES. THE 12Z GFS/NAM
SOLUTIONS PUSH THE UPPER TROUGH AXIS WELL EAST INTO THE OHIO
RIVER VALLEY AND DEEPEN IT TO A CLOSED LOW THROUGH MONDAY...WHILE
THEIR ENSEMBLE COUNTERPARTS ARE MUCH SLOWER AND DEVELOP THE CLOSED
LOW OVER THE LOWER MS RIVER VALLEY. THE ECMWF AND CANADIAN SOLUTIONS
ARE CLOSER TO THE GFS AND SREF ENSEMBLES SO THIS FORECAST IS MUCH
CLOSER TO THE ECMWF...WHICH IS COOLER FOR THE EASTERN HALF OF NM
THROUGH EARLY NEXT WEEK.
A 587DM H5 UPPER HIGH WILL STILL DEVELOP OVER SOUTHERN CALIFORNIA IN
THE MEANTIME...HOWEVER ITS MAIN ROLE WILL BE TO DEVELOP SURFACE HIGH
PRESSURE OVER THE CENTRAL ROCKIES AND ALLOW FOR A DECENT COLD FRONT
TO MOVE SOUTH DOWN THE PLAINS TUESDAY. SKIES WILL REMAIN MOSTLY
SUNNY WITH THIN HIGH CLOUDS TRAVERSING SE OVER THE EASTERN PERIPHERY
OF THE RIDGE.
DESPITE MODEL DIFFERENCES IN THE MEDIUM RANGE...THE EXTENDED GFS...
ECMWF AND CANADIAN GUIDANCE COME INTO EXCEPTIONALLY GOOD AGREEMENT
FOR LATE NEXT WEEK. THE 587DM H5 RIDGE SLIDES WEST OFF THE CALIFORNIA
COAST THEN SHARPENS TO THE NORTHWEST INTO THE GULF OF ALASKA THROUGH
THURSDAY. THIS ALLOWS A POWERFUL 1050MB SURFACE HIGH TO SLIDE DOWN
THE FRONT RANGE WHILE AN UPPER WAVE BEGINS TO DIG INTO THE GREAT
BASIN. THE COLDEST AIR OF THE SEASON IS POSSIBLE WITH THIS SYSTEM
BY THE END OF THE WEEK. THE UPPER WAVE THEN DEEPENS AND SLIDES EAST
ACROSS NM WITH ABUNDANT MOIST ADVECTION AND THE POTENTIAL FOR OUR
FIRST BIG WINTER STORM.
GUYER
&&
.AVIATION...
UPPER TROUGH AXIS STRETCHED NORTH TO SOUTH ALONG THE EAST SLOPES OF
THE CENTRAL MOUNTAIN CHAIN AT 20Z WILL CONTINUE TO TRACK EASTWARD
AND EXIT NEW MEXICO BY 26/06Z. ISOLD TSRA WILL BE FOUND ALONG
THE AXIS...WITH -SHRA AND MOUNTAIN -SHRASN ELSEWHERE. CONVECTION
WILL OCCASIONALLY OBSCURE HIGHER TERRAIN WITH MAINLY MVFR VSBYS/CIGS.
SURFACE WIND SHIFT TO NW/N OVER ERN HALF OF STATE BEFORE 26/00Z WITH
OCCASIONAL GUSTS TO AROUND 35KT.
DRYING EXPECTED IN THE WAKE OF THE TROUGH FROM THE FAR NW AND WEST
CENTRAL SPREADING EASTWARD THROUGH 26/12Z BUT SOME LINGERING LOW
LEVEL MOISTURE MAY RESULT IN ISOLD IFR CIGS/VSBYS MAINLY IN VALLEYS
OF THE NORTHERN MOUNTAINS. AT LEAST ONE SHORT WAVE IN THE NORTHWEST
FLOW ALOFT WILL PLUNGE INTO EASTERN NEW MEXICO LATE TONIGHT/SATURDAY
TO KEEP A STRONG GRADIENT BOTH ALOFT AND AT THE SURFACE...LEADING TO
GUSTY WINDS PERSISTING IN THAT REGION.
NEXT AVIATION DISCUSSION SCHEDULED FOR 10Z.
&&
.FIRE WEATHER...
WETTING PRECIPITATION WILL CONTINUE TO TAPER OFF FOR THE REST OF THE
AFTERNOON AS THE UPPER TROUGH AXIS TRACKS EAST AND OUT OF NEW
MEXICO. HOWEVER...A FEW THUNDERSTORMS WILL BE FOUND OVER THE EASTERN
PLAINS IMMEDIATELY ALONG THE TROUGH AXIS THIS AFTERNOON. IN
ADDITION...GUSTY NORTHWEST TO NORTH WINDS WILL RAKE A GOOD PART OF
NORTHERN AND CENTRAL NEW MEXICO. THESE WINDS WILL HELP DRY THE
BOUNDARY LAYER TONIGHT FROM NORTHWEST TO SOUTHEAST...BUT SOME
LINGERING LOW LEVEL MOISTURE MAY RESULT IN PATCHY LOW CLOUDS IN
SOME NORTHERN AND/OR SOUTHWEST MOUNTAIN VALLEYS.
THEREFORE...HUMIDITY RECOVERIES SHOULD BE AT LEAST GOOD.
GUSTY NORTHWEST TO NORTH WINDS WILL PERSIST SATURDAY MAINLY OVER THE
EASTERN PLAINS AS THE UPPER RIDGE BUILDS FROM THE WEST AND AT LEAST
ONE MORE SHORT WAVE DIVES SOUTH OUT OF COLORADO. IT SHOULD BE DRY
AREA WIDE WITH TEMPERATURES SLOW TO WARM...ESPECIALLY IN THE
NORTHEAST. VENTILATION WILL BE FAIR TO POOR OVER ALL BUT THE
NORTHEAST PLAINS AND ALONG THE TEXAS BORDER.
NOT MUCH CHANGE IN THE UPPER AIR PATTERN IS ANTICIPATED ON SUNDAY AS
THE RIDGE BUILDS SHARPLY OVER ARIZONA AND WESTERN NEW MEXICO. THE
GRADIENT RELAXES...RESULTING IN LESS WIND OVERALL AND POOR
VENTILATION AREA WIDE. DAYTIME TEMPERATURES SHOULD REBOUND TO WITHIN
A FEW DEGREES OF NORMAL.
THE UPPER RIDGE FLATTENS SLIGHTLY ON MONDAY...ALLOWING A SURFACE
FRONT TO APPROACH THE NORTHEAST CORNER OF NEW MEXICO IN THE
AFTERNOON. CONSEQUENTLY...VENTILATION IMPROVES SOMEWHAT IN THE EAST
BUT REMAINS POOR IN THE WEST. THE FRONT MOVES THROUGH THE PLAINS
MONDAY NIGHT BUT SHOULD BE DRY.
IT SHOULD BE A LITTLE COOLER IN THE EAST TUESDAY...BUT VENTILATION
WILL REMAIN POOR TO FAIR AREA WIDE. EXTENDED FORECAST MODELS ARE
INDICATING AN IMPRESSIVE WINTER STORM SYSTEM COULD DEVELOP IN SPLIT
FLOW OVER THE WESTERN U.S. SOMETIME MID TO LATE NEXT WEEK. THIS
COULD IMPACT NEW MEXICO NEXT THURSDAY THROUGH SATURDAY...BUT THAT
COULD CHANGE.
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 26 49 22 53 / 0 0 0 0
DULCE........................... 19 46 15 52 / 0 0 0 0
CUBA............................ 21 48 19 54 / 0 0 0 0
GALLUP.......................... 20 48 14 55 / 0 0 0 0
EL MORRO........................ 19 45 14 52 / 0 0 0 0
GRANTS.......................... 18 48 13 55 / 0 0 0 0
QUEMADO......................... 19 49 16 56 / 0 0 0 0
GLENWOOD........................ 30 61 28 61 / 0 0 0 0
CHAMA........................... 20 42 19 48 / 0 0 0 0
LOS ALAMOS...................... 31 43 29 50 / 0 0 0 0
PECOS........................... 27 42 26 49 / 0 0 0 0
CERRO/QUESTA.................... 21 39 16 48 / 0 0 0 0
RED RIVER....................... 17 33 4 44 / 5 0 0 0
ANGEL FIRE...................... 19 37 5 46 / 5 0 0 0
TAOS............................ 19 43 14 52 / 0 0 0 0
MORA............................ 25 41 23 50 / 0 0 0 0
ESPANOLA........................ 23 49 20 55 / 0 0 0 0
SANTA FE........................ 26 44 24 52 / 0 0 0 0
SANTA FE AIRPORT................ 25 47 21 53 / 0 0 0 0
ALBUQUERQUE FOOTHILLS........... 29 48 30 53 / 0 0 0 0
ALBUQUERQUE HEIGHTS............. 33 50 29 53 / 0 0 0 0
ALBUQUERQUE VALLEY.............. 31 52 24 54 / 0 0 0 0
ALBUQUERQUE WEST MESA........... 28 52 24 54 / 0 0 0 0
LOS LUNAS....................... 27 52 20 55 / 0 0 0 0
RIO RANCHO...................... 26 51 25 54 / 0 0 0 0
SOCORRO......................... 31 54 28 58 / 0 0 0 0
SANDIA PARK/CEDAR CREST......... 27 47 26 51 / 0 0 0 0
TIJERAS......................... 27 48 24 52 / 0 0 0 0
MORIARTY/ESTANCIA............... 23 43 18 49 / 0 0 0 0
CLINES CORNERS.................. 26 43 25 48 / 5 0 0 0
GRAN QUIVIRA.................... 28 48 26 52 / 0 0 0 0
CARRIZOZO....................... 30 51 26 53 / 0 0 0 0
RUIDOSO......................... 26 46 24 48 / 5 0 0 0
CAPULIN......................... 24 38 20 51 / 20 0 0 0
RATON........................... 25 45 19 61 / 5 0 0 0
SPRINGER........................ 24 43 20 59 / 5 0 0 0
LAS VEGAS....................... 26 42 23 54 / 5 0 0 0
CLAYTON......................... 28 42 28 58 / 30 0 0 0
ROY............................. 27 42 24 55 / 10 0 0 0
CONCHAS......................... 32 48 25 60 / 5 0 0 0
SANTA ROSA...................... 31 47 27 60 / 0 0 0 0
TUCUMCARI....................... 32 46 26 58 / 10 0 0 0
CLOVIS.......................... 32 46 27 54 / 0 0 0 0
PORTALES........................ 32 47 25 56 / 5 0 0 0
FORT SUMNER..................... 34 49 26 59 / 0 0 0 0
ROSWELL......................... 36 51 25 59 / 0 0 0 0
PICACHO......................... 33 48 25 57 / 0 0 0 0
ELK............................. 30 47 24 52 / 0 0 0 0
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
GUYER
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
909 PM CST SAT NOV 26 2011
.UPDATE...
FORECAST CHALLENGE FOR THE NIGHT IS EASTWARD MOVEMENT OF
CLOUD DECK AND TEMPS. LATEST SAT IMAGERY HAS SHOWN THE CLEARING
LINE ACROSS THE FAR WESTERN ZONES OF THE FCST AREA...MAKING LITTLE
PROGRESS TO THE EAST SINCE 22Z. LOOKING AT THE THE RUC MODEL 925-850
RH LAYER...THE MOISTURE IN THE LOWER LAYERS WILL NOT BEGIN MAKING
SIGNIFICANT EASTWARD PROGRESSION UNTIL AFTER 06Z. ADJUSTMENTS TO
THE TEMP GRIDS HAVE BEEN MADE FOR THE EASTERN ZONES TO REFLECT THE
DELAY IN CLEARING. WINDS SHOULD BEGIN TO SUBSIDE IN THE 06-09Z
TIME PERIOD AS HIGH PRESSURE BUILDS INTO THE AREA LATER TONIGHT.
OTHERWISE REST OF FCST LOOKS GOOD SO NO CHANGES WERE MADE.
&&
.AVIATION...
CIGS GENERALLY MVFR EAST OF THE RIVER VALLEY THIS EVENING AND MVFR
TO VFR WEST OF THE VALLEY. WINDS WILL CONTINUE FROM THE NORTHWEST
IN THE 10 TO 20 KT RANGE. EXPECT IMPROVING SKY CONDS THROUGH THE
NIGHT WITH WINDS DIMINISHING TOWARD SUNRISE. WIND WILL TURN WSW
SUN AFTN DECREASING TO BELOW 10 KTS. EXPECT SCATTERED CU DECK AOB
4K FT.
&&
.PREV DISCUSSION... /ISSUED 302 PM CST SAT NOV 26 2011/
SHORT TERM...TONIGHT THROUGH TUESDAY
PRIMARY FORECAST CHALLENGES CONCERN CLOUD TRENDS...TEMPERATURES...
PRECIPITATION AND WIND OVER THE NEXT 12 TO 18 HOURS. GFS/NAM/
ECMWF/GEM HEIGHT/PRESSURE FIELDS ARE IN GOOD AGREEMENT...BUT ALL
MODELS ARE OVERDONE ON QPF. FOR PRECIPITATION...WILL USE CURRENT
RADAR TRENDS AND RUC MODEL DATA FOR GUIDANCE.
20 UTC SURFACE OBSERVATIONS SHOW LIGHT SNOW FROM ROSEAU TO FOSSTON
TO ALEXANDRIA AND POINTS EAST. RADAR ECHOES ARE WEAK TO NON-
EXISTENT...SO ANY NEW SNOW ACCUMULATION SHOULD BE MINIMAL. THE
SURFACE LOW HAS MOVED INTO THE UPPER PENINSULA OF MI WITH AN
INVERTED TROUGH INTO SOUTHWEST ONTARIO. KEPT SOME SLIGHT CHANCE
POPS OR FLURRIES ACROSS THE FAR EASTERN FORECAST AREA THIS EVENING
AND OVERNIGHT...BUT ALL AREAS SHOULD DRY OUT BY 12 UTC SUNDAY
MORNING.
OVERCAST SKIES HAVE PLAGUED THE FORECAST AREA ALL DAY WITH THE
CLEARING LINE NOW FROM RUGBY TO ABERDEEN. IT IS THESE CLOUDS THAT
HAVE LIKELY LIMITED BOUNDARY LAYER MIXING AND HIGHER WIND SPEEDS
THIS AFTERNOON. A FEW SPOTS FROM COOPERSTOWN TO VALLEY CITY HAVE
BRIEFLY TOUCHED WIND ADVISORY CRITERIA THIS AFTERNOON. FOR NOW...
WILL LEAVE ADVISORY IN PLACE AS SOME CLEARING WEST OF THE VALLEY
BEFORE SUNSET SHOULD ENCOURAGE 35 KT WINDS NEAR 2000 FT TO MIX TO
THE SURFACE.
TEMPERATURES TONIGHT WILL BE HIGHLY DEPENDENT ON CLOUD COVER. WITH
CLEARING SKIES ALONG AND WEST OF THE VALLEY FOR MUCH OF THE NIGHT
AND CURRENT DEW POINT TEMPERATURES ACROSS CENTRAL ND IN THE SINGLE
DIGITS TO TEENS ABOVE ZERO...EXPECT LOWS TO DIP DOWN INTO THE LOW
TEENS TONIGHT ACROSS EASTERN ND. DEPENDING ON THE FULL EXTENT OF
NEAR SURFACE DRYING THAT TAKES PLACE...TEMPERATURES MAY DROP EVEN
FURTHER. TO THE EAST WHERE CLOUD COVER WILL BE SLOWER TO ERODE...
UPPER TEENS TO LOW 20S SEEM REASONABLE AT THIS TIME.
SUNDAY WILL BE DRY AND SLIGHTLY WARMER AS SURFACE HIGH PRESSURE
NOSES INTO THE NORTHERN PLAINS. A DRY COLD FRONT WILL DROP SOUTH
ACROSS THE FORECAST AREA MONDAY AFTERNOON...BUT TEMPERATURES IN
THE 925 TO 850 HPA LAYER FROM +2 TO +8 C AHEAD OF THE FRONT SHOULD
ALLOW HIGHS TO CLIMB INTO THE MID 30S TO LOWER 40S. SURFACE HIGH
PRESSURE RE-ESTABLISHES ITSELF ON TUESDAY...BUT FULL EXTENT OF
COOLING AFTER FRONTAL PASSAGE WILL TAKE AFFECT WITH HIGHS ONLY IN
THE LOWER TO MID 30S.
LONG TERM...TUESDAY NIGHT THROUGH SATURDAY
MODELS INITIALIZED WELL THIS RUN AND REMAIN IN RELATIVELY GOOD
AGREEMENT...SO WENT WITH A BLENDED SOLN ATTM. BROAD UPPER RIDGE IS
IN PLACE EARLY IN THE PERIOD SO LOOKING AT SLIGHTLY ABOVE NORMAL
TEMPS AND LITTLE PCPN. A VIGOROUS SHORT WAVE IS EXPECTED TO CROSS
THE AREA LATE WED BRINGING A COLD FRONT...SLIGHTLY COOLER
TEMPS...AND A SLIGHT CHANCE FOR MEASURABLE PCPN. OTHERWISE...THE
UPPER RIDGE QUICKLY REBOUNDS...AND RETURN FLOW AT THE SURFACE WILL
BRING A RETURN TO A BIT WARMER TEMPS BY THE END OF THE PERIOD.
AVIATION...
VFR CIGS ARE WORKING THEIR WAY ACROSS THE DEVILS LAKE BASIN. OTHER
TAF SITES REMAIN MVFR OR IFR. AS SURFACE LOW PRESSURE CONTINUES TO
MOVE EAST ACROSS THE GREAT LAKES...A SFC RIDGE AND RETURN FLOW WILL
HELP DRY OUT THE BOUNDARY LAYER. CLEARING SHOULD SPREAD FROM WEST TO
EAST OVERNIGHT AND IS REFLECTED IN THE TAFS...WITH THE LAST SITES
SCATTERING OUT BY 09Z.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
FRAZIER
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1230 AM EST FRI NOV 25 2011
.SYNOPSIS...
HIGH PRESSURE WITH DRY WEATHER CONTINUES THROUGH SATURDAY. MORE RAIN
SUNDAY WITH THE NEXT LOW PRESSURE SYSTEM. TURNING COLDER WITH RAIN
AND SNOW SHOWERS EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
UPDATE...
HAVE MADE SOME SIGNIFICANT ADJUSTMENTS TO THE OVERNIGHT LOW
TEMPERATURES WITH THIS UPDATE. COOL SPOTS/VALLEYS HAVE DROPPED
QUICKLY...WHILE ELEVATED SITES IN THE WARMER BOUNDARY LAYER AIR
STILL REMAIN IN THE 40S IN SOME LOCATIONS. THIS INCLUDES SNOWSHOE.
LOCAL COOP MOS GUIDANCE IS BULLISH ON SOME OF THE LOWS GETTING
DOWN INTO THE MID 20S TONIGHT FOR PLACES LIKE NORTHEAST KENTUCKY
AND NORTHEAST OF PKB. SAME GUIDANCE ALSO SUGGESTS TEENS IN THE
GREENBRIER VALLEY OF POCAHONTAS COUNTY.
STILL ON BOARD WITH THE RUC AND THE LOW LEVEL STRATUS DECK
REDEVELOPING NEAR THE OHIO RIVER VALLEY INTO SOUTHEAST OHIO. EXTENT
OF THE OVERALL CLEARING CURRENTLY TAKING PLACE IS DECREASING
CONFIDENCE AT THE TIME OF THIS ISSUANCE.
PREVIOUS DISCUSSION...
NO SMELL OF TURKEY HERE. EVEN UNDER THE HIGH PRESSURE...THERE ARE
ISSUES. STRATUS UNDER THE TEMPERATURE INVERSION CONTINUES TO ERODE
FROM THE SOUTH. BY 22Z SUNSET...FIGURING THE STRATUS ONLY LEFT IN
OHIO.
WILL TRY TO REFORM...OR ADVECT...SOME OF THAT STRATUS 06Z TO 12Z
FRIDAY BACK IN SOUTHEAST OHIO AND MAYBE REACHING INTO NORTHWESTERN
WEST VIRGINIA INCLUDING THE PKB VCNTY. WITH WARMER BOUNDARY LAYER
TEMPERATURES...DO NOT THINK THE STRATUS WILL REFORM IN SOUTHERN WEST
VIRGINIA. SO CAN NOT RULE OUT SOME LOCAL VALLEY FOG IN THE DEEPER
VALLEYS THERE...UNDER THE CLEAR SKY 06Z TO 13Z.
HAVE NOT REEVALUATED TEMPERATURES...BUT DO NOT FORESEE ANY MAJOR
CHANGES THROUGH FRIDAY.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY/...
HIGH PRESSURE RIDGE ALOFT...AND A SURFACE HIGH PRESSURE WILL
PROVIDE CLEAR SKIES...AND DRY WEATHER CONDITIONS INTO THE DAY
SATURDAY.
THIS SCENARIO MEANS WARM AFTERNOON DUE TO HEATING...AND CHILLY
NIGHTS DUE TO RADIATIONAL COOLING AND STRONG SUBSIDENCE.
A LARGE DIURNAL RANGE IN TEMPERATURES WITH NEAR NORMAL LOWS BUT
ABOVE NORMAL HIGHS INTO THE 60S IS EXPECTED.
A COLD FRONT CROSS THE AREA EARLY SUNDAY. MODEL CONSENSUS SUGGEST
TEMPERATURES AT H850 REACHING MINUS 3 BY 12Z SUNDAY.
THEREFORE...EXPECT LIQUID PRECIPITATION WITH THE COLD FRONT ON
SUNDAY...PERHAPS MIXING WITH SNOW LATE OVER THE NORTHEAST
MOUNTAINS.
PEOPLE COMING BACK FROM THANKSGIVING WEEKEND COULD ENCOUNTER WET
ROADS ON SUNDAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
LOW CONFIDENCE CONTINUES IN THE LONG TERM PERIOD AS MODELS CONTINUE
TO DIFFER WITH THE HANDLING OF NEXT STORM SYSTEM...PROGGED TO MOVE
INTO THE REGION ON SUNDAY. 12Z RUN OF THE GFS INDICATES BULK OF
PRECIPITATION AND COLD FRONTAL BOUNDARY WILL BE ON THE WAY OUT OF
THE CWA BY THE START OF THE PERIOD...WITH COLDER AIR FILTERING IN
OVERNIGHT AS UPPER TROUGH CONTINUES TO PUSH EAST...WITH CAA PATTERN
FOR MONDAY. GFS THEN INDICATES A CLOSED LOW FORMING OVER THE
CAROLINAS...BEFORE TREKKING OFF TO THE EAST OVER THE ATLANTIC AS
SHORTWAVE RIDGING BUILDS INTO THE REGION. ECMWF CONTINUES TO
INDICATE A CLOSED LOW FORMING NEAR GULF STATES...BEFORE TREKKING
NORTHEAST TOWARDS THE REGION. THIS SCENARIO WOULD CREATE A PROLONGED
PERIOD OF WET WEATHER...AND WARMER TEMPERATURES THAT WOULD ALLOW FOR
THE BULK OF PRECIPITATION TO BE IN THE FORM OF RAIN. FOLLOWED HPC
THINKING...WHICH IS MORE PROGRESSIVE...AND FOLLOWS GFS MEAN SOLUN.
VERY TRICKY FORECAST IN TERMS OF PRECIPITATION TYPE ON SUNDAY
NIGHT/EARLY MONDAY. TEMPERATURES ARE EXPECTED TO BE COLD ENOUGH FOR
MUCH OF THE PRECIPITATION TO CHANGE OVER TO ALL SNOW...OR A
RAIN/SNOW MIX SUNDAY NIGHT...HOWEVER...DRIER AIR WILL ALSO BE
WORKING ITS WAY INTO UPPER AND MID LEVELS. AS A RESULT...REALLY NO
MOISTURE EXPECTED IN THE CRYSTAL GROWTH ZONE...AND IT IS
POSSIBLE...SOME OF THE PRECIPITATION MAY BE IN THE FORM OF A
FREEZING DRIZZLE...PARTICULARLY OVER THE LOWLAND COUNTIES. WITH THE
WARM GROUND TEMPERATURES HOWEVER...THIS WILL LIKELY MITIGATE ANY
MAJOR ISSUES TRAVEL WISE. FOR NOW...TO KEEP IN LINE WITH NEIGHBORS AND
DUE TO THE FACT THAT THE EVENT IS SEVERAL DAYS AWAY...KEPT
PRECIPITATION MAINLY AS SNOW OR A RAIN/SNOW MIX IN THE GRIDS. BEST
PLACE FOR ANY SNOWFALL ACCUMULATIONS SUNDAY NIGHT/MONDAY WILL BE
OVER THE NORTHERN MOUNTAIN ZONES...WHERE MODELS INDICATE AROUND 4
INCHES OR SO POSSIBLE. KEPT AMOUNTS GENERALLY LESS THAN THAT FOR
NOW...BUT WILL CONTINUE TO MONITOR FOR FUTURE FORECASTS.
PATTERN CONTINUES TO REMAIN PROGRESSIVE FOR THE REMAINDER OF THE
EXTENDED PERIOD WITH LOW FORECAST CONFIDENCE.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
DENSE RIVER VALLEY FOG FORMING ACROSS THE REGION. AFTER THE FOG
LIFTS THIS MORNING...EXPECT VFR CONDITIONS FOR THE REMAINDER OF THE
PERIOD.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z SATURDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: TIMING OF FOG FORMING AND DISSIPATING COULD
VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE FRI 11/25/11
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EST 1HRLY 01 02 03 04 05 06 07 08 09 10 11 12
CRW CONSISTENCY M L L L L L L L M H H H
HTS CONSISTENCY M L L L L L L L M H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY L L L L L L L L M H H H
PKB CONSISTENCY M M M L L M M L H H H H
CKB CONSISTENCY L L L L L L M L M H H H
AFTER 06Z SATURDAY...
IFR POSSIBLE IN RAIN AND SNOW SUNDAY INTO MONDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/ARJ/SL
NEAR TERM...KTB/26
SHORT TERM...ARJ
LONG TERM...SL
AVIATION...RPY
AREA FORECAST DISCUSSION
NWS NORMAN OK
1053 PM CST THU NOV 24 2011
.AVIATION...
/06Z TAFS/
IFR STRATUS DECK THAT HAS OVERSPREAD CENTRAL AND PARTS OF SW OK
WILL CONTINUE TO ADVANCE NORTH AND WEST OVERNIGHT AFFECTING ALL
TERMINALS WITH THE POSSIBLE EXCEPTION OF KGAG AND KWWR. AREAS OF
LIGHT FOG WILL ALSO OCCUR. LLWS EXPECTED DURING THE NIGHT AS THE
LOW LEVEL JET INCREASES. LOW CLOUDS SHOULD GRADUALLY BREAK UP DURING THE
MORNING. A COLD FRONT MOVING INTO NW OK FRIDAY EVENING WILL BRING
A CHANCE OF SHOWERS TO THE AREA... WITH GREATEST COVERAGE BEING
ACROSS NORTH CENTRAL OK.
&&
.PREV DISCUSSION... /ISSUED 816 PM CST THU NOV 24 2011/
UPDATE...
STRATUS HAS SPREAD NORTH/NORTHWEST QUICKLY THIS EVENING AND HRRR
SUGGESTS THAT THIS TREND WILL CONTINUE THROUGH THE NIGHT WITH
BROKEN TO OVERCAST SKIES LIKELY ENVELOPING THE EASTERN TWO-THIRDS
OR SO OF THE FORECAST AREA BY SUNRISE. HAVE MADE A MAJOR OVERHAUL
TO THE SKY GRIDS. ALTHOUGH THERE MAY BE SOME LOCATIONS WITH
RESTRICTED VISIBILITY... EXPECT WINDS TO REMAIN STRONG ENOUGH THAT
DO NOT EXPECT VERY MUCH DENSE FOG... ALTHOUGH THE HRRR DISAGREES
WITH THIS AND WILL CONTINUE TO WATCH TRENDS OVERNIGHT. HAVE ALSO
MADE BIG CHANGES TO THE HOURLY TEMPERATURE GRIDS DUE TO THE QUICK
DROP OF TEMPERATURES THIS EVENING AND USED THE RUC AS THE PRIMARY
SOURCE FOR THE TEMPERATURES. THIS ALSO REQUIRED SOME ADJUSTMENT TO
THE OVERNIGHT MINIMUM TEMPERATURE FORECAST ALTHOUGH IT APPEARS
THAT THESE CHANGES ARE MINOR IN MOST LOCATIONS.
PREV DISCUSSION... /ISSUED 600 PM CST THU NOV 24 2011/
AVIATION...
/00Z TAFS/
MAIN AVIATION ISSUE WILL OCCUR TONIGHT IN REGARDS TO THE
EVOLUTION AND MOVEMENT OF THE STRATUS DECK CURRENTLY IN SE OK.
BELIEVE IT WILL MOVE INTO PORTIONS OF CENTRAL AND SW OK... AND
WESTERN N-TX LATER TONIGHT... AND GIVEN MOST RECENT SATELLITE
TRENDS... IT MAY SPREAD FASTER THAN PREVIOUSLY EXPECTED. ALSO
MENTIONED LIKELIHOOD OF LLWS LATER TONIGHT IN SEVERAL LOCATIONS
AS THE LOW LEVEL JET STRENGTHENS. LOW CLOUDS EXPECTED TO SCATTER
OUT THURSDAY MORNING. MEANWHILE... A FEW SHOWERS MAY BEGIN TO
SPREAD INTO NW OK BY LATE IN THE DAY.
PREV DISCUSSION... /ISSUED 156 PM CST THU NOV 24 2011/
DISCUSSION...
CLOUDS CONTINUE TO ERODE IN SE PORTIONS OF THE FA THIS AFTERNOON.
HOWEVER... THEY ARE SLOW TO DO SO WHICH MEANS CLOUDS COULD LINGER
INTO THE EVENING. OTHERWISE... QUIET NIGHT TONIGHT WITH ONLY SOME
HIGH CLOUDS STREAMING INTO THE REGION AS UPPER TROUGH MOVING ACROSS
THE SW U.S. APPROACHES THE AREA. SHOWERS AND THUNDERSTORMS WILL BE
POSSIBLE FRIDAY AS THE STORM SYSTEM APPROACHES WITH CHANCES
EXPANDING EAST AND RAIN BECOMING MORE WIDESPREAD FRIDAY NIGHT. HEAVY
RAIN IS NOT EXPECTED WITH THIS SYSTEM. THE UPPER SYSTEM WILL EXIT
THE REGION SATURDAY WITH RAIN CHANCES ENDING FOR THE FA BY AROUND
THE MIDDLE OF THE DAY SATURDAY. A COLD FRONT WILL ALSO MOVE ACROSS
THE REGION FRIDAY NIGHT INTO SATURDAY. STRONG NORTH WINDS ARE
EXPECTED BEHIND THE FRONT SATURDAY MAKING CONDITIONS FEEL MUCH
COOLER THAN THEY ARE.
TEMPERATURES WILL WARM SUNDAY INTO MONDAY BEFORE ANOTHER COLD FRONT
MOVES ACROSS THE REGION LATE MONDAY INTO TUESDAY. THIS FRONTAL
PASSAGE IS EXPECTED TO BE DRY BUT WILL BRING A COOLER AIRMASS TO THE
REGION. MODELS SHOW ANOTHER UPPER SYSTEM AND COLD FRONT AFFECTING
THE REGION TOWARDS THE END OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 46 64 45 51 / 0 20 70 10
HOBART OK 50 64 40 50 / 0 30 50 10
WICHITA FALLS TX 51 65 46 55 / 0 20 70 10
GAGE OK 47 65 36 45 / 0 40 40 0
PONCA CITY OK 46 65 43 49 / 0 20 70 10
DURANT OK 47 65 51 56 / 0 10 70 40
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
26/25/32
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
535 PM CST SAT NOV 26 2011
.SHORT TERM...TONIGHT THROUGH TUESDAY
219 PM CST SAT NOV 26 2011
MAIN FORECAST CONCERNS ARE WITH PRECIPITATION TONIGHT AND THEN
TEMPERATURES THROUGH THE REST OF THE SHORT TERM PERIOD.
CURRENTLY AS OF 21Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED RIDGES OVER BOTH THE WEST AND EAST COASTS OF THE U.S. AND
TROUGHING IN-BETWEEN FROM MANITOBA SOUTHWARD THROUGH TEXAS. BULK OF
THE ENERGY ASSOCIATED WITH THE UPPER TROUGHING HAS BEEN DROPPING
SOUTH INTO TEXAS PER PRESSURE VALUES ON THE 1.5 PV SURFACE. STILL...
GRADUAL HEIGHT FALLS ON THE EAST SIDE OF THE UPPER TROUGH AND
SHORTWAVES MOVING THROUGH THE SOUTHWEST FLOW...COMBINED WITH LOW
LEVEL MOISTURE TRANSPORT...HELPED BRING THE LIGHT TO MODERATE RAIN
TO MUCH OF THE FORECAST AREA THIS MORNING. THIS PRECIPITATION IS
NOW ONLY AFFECTING THE FAR SOUTHEASTERN PORTION OF THE FORECAST
AREA DUE TO A DRY SLOT IN THE MID TO UPPER LEVELS PUNCHING IN
ELSEWHERE. MEANWHILE...VERY WEAK COLD CONVEYOR BELT AROUND A
1006MB SURFACE LOW IN NORTHEAST WISCONSIN IS REFLECTED BY LIGHT
RADAR RETURNS ACROSS CENTRAL MN INTO NORTHWEST WI. A MIX OF LIGHT
RAIN AND SNOW HAS BEEN REPORTED WITH THESE RADAR RETURNS...THANKS
TO SURFACE TEMPERATURES THAT HAVE BEEN FALLING ON GUSTY NORTHWEST
WINDS. OFF TO THE WEST... EVEN COLDER AIR WAS EVIDENT OVER THE
DAKOTAS INTO MONTANA WHERE 12Z 850MB TEMPS WERE OBSERVED AT -5 TO
-7C. COMPARE THIS TO OBSERVED 4-6C OVER THE AREA AT 12Z TODAY.
SKIES DO CLEAR OUT OVER THE WESTERN DAKOTAS...THOUGH...THANKS TO A
DRY 12Z GLASGOW MT SOUNDING.
TONIGHT AND SUNDAY...UPPER TROUGH OVER THE PLAINS IS FORECAST TO
GRADUALLY TRACK EAST DURING THIS PERIOD...WITH THE 500MB AXIS
SITUATED OVER LA CROSSE AT 12Z SUNDAY AND THEN OVER EASTERN
WISCONSIN AT 00Z MONDAY. SINCE THIS UPPER TROUGH IS COMING THROUGH
POSITIVELY TILTED AND AGAIN MOST OF THE ENERGY DROPPING SOUTH INTO
THE SOUTHERN PLAINS...VERY LITTLE IN THE WAY OF FORCING IS EXPECTED.
MAIN PRECIPITATION LOOKS TO BE THE CURRENT WEAK COLD CONVEYOR BELT
OVER CENTRAL MINNESOTA WHICH SHOULD SLIDE THROUGH MUCH OF THE
FORECAST AREA THIS EVENING. CANNOT RULE OUT A FEW HUNDREDTHS OF
QPF...AS INDICATED BY THE 26.12Z NAM/26.00Z ECMWF...BUT THE
PROBABILITY SEEMS TOO LOW TO GO MORE THAN A 50 PERCENT CHANCE GIVEN
NEARLY DRY 26.09Z SREF MEAN/26.12Z GFS AND GIVEN WEAK APPEARANCE OF
CONVEYOR BELT ON RADAR. PRECIPITATION TYPE WILL BE DETERMINED BY THE
SURFACE TEMPERATURE GIVEN THE WARMEST LAYER AT THE SURFACE...MAKING
IT A RAIN/SNOW SCENARIO. HOWEVER...THERE ARE SOME HINTS OF LOSS OF
ICE DUE TO SOME DRIER AIR IN THE 10000-15000 FT LAYER...WHICH COULD
ALLOW FOR JUST A LITTLE MORE LIQUID VS SNOW. NOT ENOUGH CONFIDENCE
EXISTS TO MENTION ANY FREEZING PRECIPITATION...THOUGH...DUE TO
QUESTION MARKS ON AMOUNT OF PRECIPITATION IN GENERAL AND SURFACE
TEMPERATURES LIKELY TAKING AWHILE TO FALL BELOW FREEZING. ANY
SNOW ACCUMULATION LIKELY TO BE VERY LIGHT IF AT ALL TOO. OVERNIGHT
HOURS THROUGH SUNDAY LOOK MOSTLY DRY AS THE UPPER TROUGH PUSHES
EAST AND SUBSIDENCE COMES IN. CERTAINLY MUCH COOLER WEATHER DURING
THIS PERIOD AS 850MB TEMPS TANK TO -4 TO -8C BY 12Z SUNDAY...ALONG
WITH THE BLUSTERY NORTHWEST WINDS. NOT A WHOLE LOT OF MODIFICATION
EXPECTED TOMORROW WITH CLEARING NOT COMING IN UNTIL LATE AND 850MB
TEMPS STAYING BELOW -2C. IN FACT...ANY CLEARING MAY ONLY OCCUR IN
THE FAR WESTERN FORECAST AREA.
SUNDAY NIGHT THROUGH TUESDAY...QUIET WEATHER LOOKS TO DOMINATE THE
FORECAST AREA DESPITE A FRONTAL PASSAGE LIKELY TO MOVE THROUGH VERY
LATE MONDAY. THINGS WILL BE MORE ACTIVE TO OUR SOUTHEAST AS AN UPPER
LOW FORMS OVER THE SOUTHEASTERN U.S....BUT ANY PRECIPITATION
WRAPPING BACK AROUND THIS UPPER LOW LOOKS TO STAY EAST AND SOUTH OF
CHICAGO. REGARDING THE FRONTAL PASSAGE...A NORTHERN STREAM UPPER
LEVEL TROUGH CURRENTLY OVER THE EASTERN PACIFIC IS FORECAST TO CROSS
THE DAKOTAS ON MONDAY...BRINGING A SURGE OF DOWNSLOPED WARMED AIR
INTO THE FORECAST AREA. 850MB TEMPS ACTUALLY CLIMB UP TO 4-6C BY 00Z
TUESDAY. PROBLEM IS THAT A LOT OF THE WARMING TAKES PLACE ALOFT AND
WE WILL NOT BE ABLE TO MIX UP TO IT...DUE TO THE LOW SUN ANGLE AND
LIGHT WINDS FORECAST. STILL...MIXING UP TO 925MB IS LIKELY WITH FULL
SUNSHINE RESULTING IN HIGHS IN THE UPPER 30S TO LOW 40S. THIS SHOULD
BE A NICE REBOUND AFTER SUNDAY NIGHT LOWS LIKELY IN THE MID TEENS TO
MID 20S...COLDEST IN THE TYPICAL COLD SPOTS. DRY WEATHER EXPECTED
WITH THE FRONTAL PASSAGE DUE TO LACK OF MOISTURE...THEN COOLER
TEMPERATURES COME IN AGAIN AS HIGH PRESSURE BUILDS BACK OVER THE
PLAINS FOR MONDAY NIGHT AND TUESDAY. 850MB TEMPS THIS TIME DO NOT
FALL AS MUCH...ONLY TO -2 TO -4C...SO TUESDAY SHOULD END UP A LITTLE
WARMER THAN SUNDAY. MAY HAVE SOME THICKER HIGH CLOUDS TO DEAL WITH
IN THE MORNING COMING OFF THE SOUTHEASTERN UPPER LOW TO LIMIT
FIXING...BUT THESE LOOK TO START CLEARING OUT IN THE AFTERNOON.
.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY
219 PM CST SAT NOV 26 2011
SIMILAR TO THE SUNDAY NIGHT THROUGH TUESDAY TIME PERIOD...MUCH OF
THE EXTENDED LOOKS QUIET...THOUGH PLENTY OF UNCERTAINTY EXISTS WITH
THE UPPER LEVEL PATTERN HEADING INTO NEXT WEEKEND. LONGWAVE PATTERN
FEATURES UPPER RIDGING BUILDING INTO THE AREA ON WEDNESDAY BETWEEN
THE UPPER LOW LIFTING UP THE EAST COAST AND TROUGHING DIGGING DOWN
THE WEST COAST. SHOULD SEE WARMER TEMPERATURES ON WEDNESDAY
ASSOCIATED WITH THE UPPER RIDGING...THOUGH NOT MUCH ABOVE NORMAL
GIVEN 850MB TEMPS ONLY 2-4C. THIS TROUGHING LOOKS TO SPLIT INTO
TWO...WITH THE NORTHERN STREAM PORTION CROSSING THE FORECAST AREA
THURSDAY NIGHT. MODELS HAVE BEEN SPLIT WHETHER OR NOT FRONTOGENESIS
AND DPVA FORCING AHEAD OF THE NORTHERN STREAM TROUGH CAN PRODUCE
LIGHT SNOW...MOSTLY DUE TO LACK OF MOISTURE WITH IT. CONSENSUS OF
GUIDANCE SUGGESTS JUST A 10-15 PERCENT CHANCE FOR BOTH THURSDAY AND
THURSDAY NIGHT...WHICH RESULTS IN A DRY FORECAST. MORE IMPORTANTLY
IS THE 850MB TEMPS ACCOMPANYING THE TROUGH. MODELS HAVE BEEN
INCONSISTENT INCLUDING RUN TO RUN ON HOW COLD THE AIR IS WITH IT.
CURRENT CONSENSUS IS BETWEEN -8 TO -12C...BUT HAVE SEEN MODELS BOTH
WARMER AND COLDER. THIS SHOULD SET UP TEMPERATURES BELOW NORMAL FOR
FRIDAY AS AN AREA OF HIGH PRESSURE BUILDS IN. HEADING INTO THE
WEEKEND...MODELS ARE IN AGREEMENT OF RIDGING BUILDING UP IN THE
EASTERN PACIFIC. QUESTION IS WHERE SHORTWAVES DIG DOWN TO ON THE
EAST SIDE OF THIS RIDGE. THE 26.12Z GFS AND SOME GFS ENSEMBLE
MEMBERS ALLOW SHORTWAVES TO DIG DOWN INTO THE WESTERN U.S....
RESULTING IN DOWNSTREAM RIDGING OVER THE FORECAST AREA. OTHERS LIKE
THE 26.00Z/26.12Z ECMWF AND OTHER GFS ENSEMBLE MEMBERS DIG THE
SHORTWAVES DOWN MORE OVER THE NORTHERN PLAINS INTO OUR REGION BY
MAINTAINING NORTHWEST FLOW. FOLLOWED A SOMEWHAT OF CONSENSUS
APPROACH WHICH JUST PLACES SOME 10-20 PERCENT CHANCES OVER THE AREA
ON SATURDAY...MAINLY NORTH OF I-90 WITH A SHORTWAVE TROUGH GOING
THROUGH THERE. SLIGHTLY WARMER TEMPERATURES WOULD OCCUR ON SATURDAY
AS WELL WITH WARM ADVECTION ASSOCIATED WITH THE SHORTWAVE TROUGH.
IN SUMMARY...EXTENDED LOOKS AROUND NORMAL ON TEMPERATURES WITH
MAINLY DRY CONDITIONS.
&&
.AVIATION...TONIGHT AND SUNDAY
535 PM CST SAT NOV 26 2011
AT 23Z...COLD FRONT WAS PUSHING INTO EASTERN WISCONSIN. STRONG
COLD ADVECTION IN ITS WAKE HAD OVERSPREAD BOTH TAF SITES...WITH
PRESSURE GRADIENT TIGHTENING BEHIND THE FRONT. NORTHWEST WINDS
HAVE BEEN GUSTING TO NEARLY 30 KNOTS AT KRST. EXPECT THESE GUSTY
WINDS TO CONTINUE THROUGH THE EVENING HOURS...WITH ONLY A SLOW
DECREASE AFTER 06Z. WINDS WILL PICK UP AT KLSE AS GRADIENT
TIGHTENS WITH GUSTS TO AROUND 20 KNOTS EXPECTED OVERNIGHT. DRIER
AIR WAS FILTERING INTO THE REGION FROM THE NORTHWEST...AND
CEILINGS HAVE RISEN A LITTLE AT KRST. EXPECT A SLOW RISE INTO THE
LOWER MVFR CATEGORY THROUGH THE EVENING. THESE MVFR CEILINGS WILL
THEN CONTINUE THROUGH AT LEAST 18Z SUNDAY. BIGGEST QUESTION TIS
HOW QUICKLY THE CLOUDS SCATTERED OUT AFTER 18Z SUNDAY. BUFKIT
SOUNDING FROM BOTH THE 26.18Z NAM AND GFS BOTH INDICATE CLOUDS
SCATTERING OUT BETWEEN 18Z-21Z AND THUS HAVE TRENDED THIS WAY IN
THE TAFS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
219 PM CST SAT NOV 26 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1147 AM CST FRI NOV 25 2011
.SHORT TERM...TODAY THROUGH MONDAY
301 AM CST FRI NOV 25 2011
BIG CHANGES COMING OVER THE NEXT FEW DAYS AS RAIN STARTS UP
TONIGHT AHEAD OF A COLD FRONT WHICH WILL KNOCK TEMPERATURES DOWN
ON SATURDAY. BEYOND THIS...THERE IS MUCH UNCERTAINTY FOR SATURDAY
NIGHT INTO SUNDAY WITH WHETHER AN ACCUMULATING SNOW WILL OCCUR.
CURRENTLY...MILD CONDITIONS WERE OBSERVED ACROSS THE REGION DUE
TO GUSTY SOUTH TO SOUTHWEST WINDS AT THE SURFACE AHEAD OF A COLD
FRONT THAT EXTENDS FROM SOUTHWEST ONTARIO THROUGH NORTHERN
MINNESOTA ON INTO CENTRAL SOUTH DAKOTA. FURTHER ALOFT...GENERAL
SOUTHWEST FLOW AHEAD OF TROUGHING DUE TO A NORTHERN AND SOUTHERN
STREAM LOW WAS HELPING TO ADVECT MID TO HIGH LEVEL CLOUDS INTO THE
REGION. AS THE SOUTHERN STREAM TROUGH PROPAGATES EAST INTO THE
SOUTHERN PLAINS THIS MORNING...LOW LEVEL MOISTURE ADVECTION WILL
BE ON THE INCREASE AS A SURFACE LOW DEEPENS ACROSS THE NORTHERN
PLAINS. AS A RESULT...ANOTHER LOW LEVEL STRATUS DECK IS EXPECTED
TO DEVELOP NORTHWARD THIS MORNING FROM THE SOUTHERN PLAINS. THE
LATEST IR SCANS AT 8Z SHOWS THE LEADING EDGE OF THIS STRATUS NEAR
EMPORIA KANSAS...WHICH CORRELATES WELL TO THE 25.07Z RUC
950-900MB LAYER RH. THIS RUN OF THE RUC SHOWS THE HIGHER RH VALUES
INCREASING RAPIDLY THIS MORNING ACROSS THE SOUTHEASTERN HALF OF
IOWA TOWARD THE NORTHERN HALF OF LAKE MICHIGAN BY 18Z TODAY.
25.07Z RUC AND 25.00Z NAM/GFS SOUNDINGS FROM ACROSS THE REGION
SHOW THIS HIGHER RH BEING TRAPPED UNDER A STOUT 900-850MB
INVERSION AND THEREFORE HAVE GONE WITH A MORE PESSIMISTIC CLOUD
FORECAST TODAY. THIS CLOUD COVER WILL LIMIT HOW MUCH WARMING
CAN OCCUR INTO THE AFTERNOON WITH THE HIGHS LIKELY COMING THIS
MORNING.
AFTER THE STRATUS FILLS IN...THE NEXT QUESTION IS WHEN WILL THE
RAIN START UP TONIGHT. 25.00Z NAM AND GFS SOUNDINGS SHOW A DECENT
DRY LAYER CENTERED ON 800MB THAT WILL NEED TO BE OVERCOME FOR ANY
PRECIPITATION TO MAKE IT DOWN TO THE GROUND. BASED ON THESE
SOUNDINGS AND MID LEVEL QG FORCING FIELDS...IT APPEARS THAT THE
DEEP MOISTURE AND FORCING COMES TOGETHER LATER TONIGHT AHEAD OF
THE SURFACE COLD FRONT AND MID LEVEL TROUGH. THE THERMAL PROFILE
WILL BE WARM ENOUGH FOR THIS PRECIPITATION TO BE IN ALL LIQUID
FORM THROUGH SATURDAY MORNING BEFORE THE FRONT COMES THROUGH.
AFTER THE FRONT COMES THROUGH THE REGION SATURDAY MORNING INTO
EARLY SATURDAY AFTERNOON...UNCERTAINTY TAKES OVER WITH WHAT WILL
OCCUR SATURDAY NIGHT INTO SUNDAY. THE ONE THING THAT APPEARS TO
BE CERTAIN IS THAT COLDER AIR WILL ADVECT INTO THE REGION IN THE
LOW LEVELS BRINGING MUCH OF THE THERMAL PROFILE TO BELOW FREEZING
AND SUPPORTIVE OF SNOW BEING THE PRECIPITATION TYPE.
THE MAIN UNCERTAINTY LIES WITH THE DIFFERENCES BETWEEN THE US AND
NON-US MODEL SOLUTIONS WITH THE STRENGTH AND TRACK OF THE TROUGH.
BASED ON INPUT FROM HPC/S MODEL DIAGNOSTICS DESK...THE UNFAVORED
SOLUTION IS THE 25.00Z NAM/GFS AND 24.21Z SREF MEAN WHICH PRODUCE
A DEEPER...CLOSED OFF MID LEVEL LOW WHICH BRINGS THE DEFORMATION
AXIS THROUGH THE HEART OF THE FORECAST AREA. THESE SOLUTIONS WOULD
LIKELY LEAD TO AN ACCUMULATING SNOW ACROSS MUCH OF THE REGION.
THESE MODELS ALSO DEVELOPS A VERY TIGHT PRESSURE GRADIENT IN THE
LOW LEVEL COLD AIR ADVECTION POCKET ON THE SOUTHWEST SIDE OF THE
SURFACE LOW WHICH WOULD BRING GUSTS UP NEAR ADVISORY CRITERIA.
HOWEVER...AT THIS POINT THE FAVORED SOLUTION FOR SATURDAY NIGHT
INTO SUNDAY IS WITH THE 25.00Z ECMWF/UKMET/CANADIAN MODELS. THESE
FORMS OF GUIDANCE ALL SHOW A MUCH LESS AMPLIFIED...OPEN MID LEVEL
WAVE WITH HARDLY ANY SNOW COMING THROUGH SATURDAY NIGHT.
BASED ON THIS INPUT FROM HPC ...HAVE BACKED OFF ON THE PROBABILITY
FOR PRECIPITATION AND THE WIND GUSTS JUST A TAD ON SATURDAY NIGHT.
FOR ADDITIONAL INFORMATION ON THIS FAVORED TREND...PLEASE SEE THE
LATEST PMDHMD FROM HPC.
COLD AIR WILL REMAIN IN PLACE UNTIL MONDAY WHEN A BRIEF SHOT OF
LOW LEVEL WARM AIR ADVECTION COMES THROUGH THE REGION.
.LONG TERM...MONDAY NIGHT THROUGH THURSDAY NIGHT
301 AM CST FRI NOV 25 2011
NOT A WHOLE LOT OF CONFIDENCE GOING INTO THE EXTENDED PERIOD DUE
TO THE ISSUES THIS WEEKEND...BUT HAVE TRENDED TOWARD THE 25.00Z
ECMWF/GEM/UKMET FORECAST WHICH CUT OFF A MID LEVEL LOW ALONG THE
GULF COAST EARLY NEXT WEEK AND SLOWLY BRINGS IT TOWARD THE
NORTHEASTERN US INTO MID WEEK. THIS SETUP WILL KEEP THE REGION IN
A COOL NORTHWESTERLY FLOW ALOFT AND LIMIT ANY KIND OF WARMING
TRENDS. NOT MUCH IN THE WAY OF PRECIPITATION CHANCES EXCEPT FOR AN
OPEN MID LEVEL TROUGH THAT DIVES SOUTHEAST TOWARD THE GREAT LAKES
ON THURSDAY WHICH COULD BRING SOME PRECIPITATION WITH IT.
&&
.AVIATION...THROUGH 18Z SATURDAY
1147 AM CST FRI NOV 25 2011
STRATUS HAS MOVED IN FROM THE SOUTHWEST INTO BOTH TAF SITES...WITH
MVFR CEILINGS AT KLSE AND IFR CEILINGS AT KRST. THESE CEILINGS ARE
LIKELY TO PERSIST INTO EARLY THIS EVENING...AND THEN GRADUALLY
START FALLING WITH NOCTURNAL COOLING AND MORESO AFTER MIDNIGHT
WHEN RAIN IS FORECAST TO OCCUR. ANTICIPATING BOTH SITES AT IFR AT
08Z WITH LIFR CONDITIONS LIKELY AS WELL. VFR VISIBILITIES SHOULD
REMAIN THE RULE THROUGH THE EVENING...THOUGH CANNOT RULE OUT BRIEF
TIMES OF KRST DROPPING TO MVFR BEFORE THEN GIVEN THE 6SM VISIBILITY
AT 17Z. BETTER SHOT OF MVFR VISIBILITIES COMES AFTER 06Z TONIGHT
AND EVEN IFR VISIBILITIES TOWARDS 12Z WITH THE RAIN. THE RAIN THAT
IS FORECAST IS DUE TO A TROUGH OF LOW PRESSURE MOVING INTO THE TAF
SITES. PLAN ON THIS TROUGH TO MOVE THROUGH THE TAF SITES BETWEEN
12-15Z SATURDAY. IN ITS WAKE...PRECIPITATION WILL END ALLOWING
VISIBILITIES AND CEILINGS TO CLIMB. STILL HAVE CEILINGS ONLY
CLIMBING TO IFR AT BOTH TAF SITES LEADING UP TO 18Z...BUT IT
CERTAINLY POSSIBLE THAT THEY COULD REACH MVFR AROUND 18Z. IN
ADDITION...LOOK FOR WINDS TO TURN FROM SOUTHERLY TO WEST BEHIND
THE TROUGH. GUSTS TO 20 KT OR SO ARE POSSIBLE AT KRST AFTER 15Z
AND SHOULD INCREASE FURTHER AFTER 18Z WHEN COLD AIR FLOWS IN.
&&
.CLIMATE...FOR TODAY
301 AM CST FRI NOV 25 2011
RECORD HIGHEST LOWS MAY BE BROKEN TODAY AT BOTH ROCHESTER AND LA
CROSSE WITH TEMPERATURES THIS MORNING FAIRLY MILD IN THE UPPER 40S
TO AROUND 50. THE RECORD HIGHEST LOW TEMPERATURE FOR ROCHESTER
TODAY IS 37 FROM 1915. THE RECORD HIGHEST LOW TEMPERATURE FOR LA
CROSSE TODAY IS 42 IN 1998. FORECAST TEMPERATURES AT MIDNIGHT
TONIGHT ARE EXPECTED TO BE ABOVE THESE VALUES.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
301 AM CST FRI NOV 25 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...AJ
CLIMATE...HALBACH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
551 AM CST FRI NOV 25 2011
.SHORT TERM...TODAY THROUGH MONDAY
301 AM CST FRI NOV 25 2011
BIG CHANGES COMING OVER THE NEXT FEW DAYS AS RAIN STARTS UP
TONIGHT AHEAD OF A COLD FRONT WHICH WILL KNOCK TEMPERATURES DOWN
ON SATURDAY. BEYOND THIS...THERE IS MUCH UNCERTAINTY FOR SATURDAY
NIGHT INTO SUNDAY WITH WHETHER AN ACCUMULATING SNOW WILL OCCUR.
CURRENTLY...MILD CONDITIONS WERE OBSERVED ACROSS THE REGION DUE
TO GUSTY SOUTH TO SOUTHWEST WINDS AT THE SURFACE AHEAD OF A COLD
FRONT THAT EXTENDS FROM SOUTHWEST ONTARIO THROUGH NORTHERN
MINNESOTA ON INTO CENTRAL SOUTH DAKOTA. FURTHER ALOFT...GENERAL
SOUTHWEST FLOW AHEAD OF TROUGHING DUE TO A NORTHERN AND SOUTHERN
STREAM LOW WAS HELPING TO ADVECT MID TO HIGH LEVEL CLOUDS INTO THE
REGION. AS THE SOUTHERN STREAM TROUGH PROPAGATES EAST INTO THE
SOUTHERN PLAINS THIS MORNING...LOW LEVEL MOISTURE ADVECTION WILL
BE ON THE INCREASE AS A SURFACE LOW DEEPENS ACROSS THE NORTHERN
PLAINS. AS A RESULT...ANOTHER LOW LEVEL STRATUS DECK IS EXPECTED
TO DEVELOP NORTHWARD THIS MORNING FROM THE SOUTHERN PLAINS. THE
LATEST IR SCANS AT 8Z SHOWS THE LEADING EDGE OF THIS STRATUS NEAR
EMPORIA KANSAS...WHICH CORRELATES WELL TO THE 25.07Z RUC
950-900MB LAYER RH. THIS RUN OF THE RUC SHOWS THE HIGHER RH VALUES
INCREASING RAPIDLY THIS MORNING ACROSS THE SOUTHEASTERN HALF OF
IOWA TOWARD THE NORTHERN HALF OF LAKE MICHIGAN BY 18Z TODAY.
25.07Z RUC AND 25.00Z NAM/GFS SOUNDINGS FROM ACROSS THE REGION
SHOW THIS HIGHER RH BEING TRAPPED UNDER A STOUT 900-850MB
INVERSION AND THEREFORE HAVE GONE WITH A MORE PESSIMISTIC CLOUD
FORECAST TODAY. THIS CLOUD COVER WILL LIMIT HOW MUCH WARMING
CAN OCCUR INTO THE AFTERNOON WITH THE HIGHS LIKELY COMING THIS
MORNING.
AFTER THE STRATUS FILLS IN...THE NEXT QUESTION IS WHEN WILL THE
RAIN START UP TONIGHT. 25.00Z NAM AND GFS SOUNDINGS SHOW A DECENT
DRY LAYER CENTERED ON 800MB THAT WILL NEED TO BE OVERCOME FOR ANY
PRECIPITATION TO MAKE IT DOWN TO THE GROUND. BASED ON THESE
SOUNDINGS AND MID LEVEL QG FORCING FIELDS...IT APPEARS THAT THE
DEEP MOISTURE AND FORCING COMES TOGETHER LATER TONIGHT AHEAD OF
THE SURFACE COLD FRONT AND MID LEVEL TROUGH. THE THERMAL PROFILE
WILL BE WARM ENOUGH FOR THIS PRECIPITATION TO BE IN ALL LIQUID
FORM THROUGH SATURDAY MORNING BEFORE THE FRONT COMES THROUGH.
AFTER THE FRONT COMES THROUGH THE REGION SATURDAY MORNING INTO
EARLY SATURDAY AFTERNOON...UNCERTAINTY TAKES OVER WITH WHAT WILL
OCCUR SATURDAY NIGHT INTO SUNDAY. THE ONE THING THAT APPEARS TO
BE CERTAIN IS THAT COLDER AIR WILL ADVECT INTO THE REGION IN THE
LOW LEVELS BRINGING MUCH OF THE THERMAL PROFILE TO BELOW FREEZING
AND SUPPORTIVE OF SNOW BEING THE PRECIPITATION TYPE.
THE MAIN UNCERTAINTY LIES WITH THE DIFFERENCES BETWEEN THE US AND
NON-US MODEL SOLUTIONS WITH THE STRENGTH AND TRACK OF THE TROUGH.
BASED ON INPUT FROM HPC/S MODEL DIAGNOSTICS DESK...THE UNFAVORED
SOLUTION IS THE 25.00Z NAM/GFS AND 24.21Z SREF MEAN WHICH PRODUCE
A DEEPER...CLOSED OFF MID LEVEL LOW WHICH BRINGS THE DEFORMATION
AXIS THROUGH THE HEART OF THE FORECAST AREA. THESE SOLUTIONS WOULD
LIKELY LEAD TO AN ACCUMULATING SNOW ACROSS MUCH OF THE REGION.
THESE MODELS ALSO DEVELOPS A VERY TIGHT PRESSURE GRADIENT IN THE
LOW LEVEL COLD AIR ADVECTION POCKET ON THE SOUTHWEST SIDE OF THE
SURFACE LOW WHICH WOULD BRING GUSTS UP NEAR ADVISORY CRITERIA.
HOWEVER...AT THIS POINT THE FAVORED SOLUTION FOR SATURDAY NIGHT
INTO SUNDAY IS WITH THE 25.00Z ECMWF/UKMET/CANADIAN MODELS. THESE
FORMS OF GUIDANCE ALL SHOW A MUCH LESS AMPLIFIED...OPEN MID LEVEL
WAVE WITH HARDLY ANY SNOW COMING THROUGH SATURDAY NIGHT.
BASED ON THIS INPUT FROM HPC ...HAVE BACKED OFF ON THE PROBABILITY
FOR PRECIPITATION AND THE WIND GUSTS JUST A TAD ON SATURDAY NIGHT.
FOR ADDITIONAL INFORMATION ON THIS FAVORED TREND...PLEASE SEE THE
LATEST PMDHMD FROM HPC.
COLD AIR WILL REMAIN IN PLACE UNTIL MONDAY WHEN A BRIEF SHOT OF
LOW LEVEL WARM AIR ADVECTION COMES THROUGH THE REGION.
.LONG TERM...MONDAY NIGHT THROUGH THURSDAY NIGHT
301 AM CST FRI NOV 25 2011
NOT A WHOLE LOT OF CONFIDENCE GOING INTO THE EXTENDED PERIOD DUE
TO THE ISSUES THIS WEEKEND...BUT HAVE TRENDED TOWARD THE 25.00Z
ECMWF/GEM/UKMET FORECAST WHICH CUT OFF A MID LEVEL LOW ALONG THE
GULF COAST EARLY NEXT WEEK AND SLOWLY BRINGS IT TOWARD THE
NORTHEASTERN US INTO MID WEEK. THIS SETUP WILL KEEP THE REGION IN
A COOL NORTHWESTERLY FLOW ALOFT AND LIMIT ANY KIND OF WARMING
TRENDS. NOT MUCH IN THE WAY OF PRECIPITATION CHANCES EXCEPT FOR AN
OPEN MID LEVEL TROUGH THAT DIVES SOUTHEAST TOWARD THE GREAT LAKES
ON THURSDAY WHICH COULD BRING SOME PRECIPITATION WITH IT.
&&
.AVIATION...THROUGH 12Z SATURDAY
551 AM CST FRI NOV 25 2011
IMMEDIATE CONCERN THIS MORNING DEALS WITH LLWS AT KLSE WITH WINDS
AROUND 35-45KT AROUND 2000FT AGL AND WINDS BELOW 5KT AT THE SURFACE
AS OF 12Z. LOW LEVEL JET AND THUS LLWS EXPECTED TO SLACKEN THIS
MORNING BY 14Z. CONCERN THEN SHIFTS TO SOUTHERLY FLOW ADVECTING
MVFR/IFR STRATUS INTO THE AREA LATER THIS MORNING FROM THE CENTRAL
PLAINS. HAVE CIGS GOING BKN AROUND 800 FEET AT KRST BY 16Z AND
AROUND 1200 FEET AT KLSE AT THE SAME TIME.
FOR TONIGHT...WILL BE WATCHING A LOW PRESSURE SYSTEM AND COLD FRONT
PUSHING EASTWARD INTO THE AREA...SPREADING SCATTERED SHOWERS IN THIS
EVENING...AND MORE WIDESPREAD RAIN/AREAS OF FOG IN AFTER MIDNIGHT. IFR
CONDITIONS EXPECTED TO CONTINUE AT KRST WHILE MVFR CONDITIONS AT
KLSE EXPECTED TO DETERIORATE INTO IFR AFTER 08Z.
&&
.CLIMATE...FOR TODAY
301 AM CST FRI NOV 25 2011
RECORD HIGHEST LOWS MAY BE BROKEN TODAY AT BOTH ROCHESTER AND LA
CROSSE WITH TEMPERATURES THIS MORNING FAIRLY MILD IN THE UPPER 40S
TO AROUND 50. THE RECORD HIGHEST LOW TEMPERATURE FOR ROCHESTER
TODAY IS 37 FROM 1915. THE RECORD HIGHEST LOW TEMPERATURE FOR LA
CROSSE TODAY IS 42 IN 1998. FORECAST TEMPERATURES AT MIDNIGHT
TONIGHT ARE EXPECTED TO BE ABOVE THESE VALUES.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
301 AM CST FRI NOV 25 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...RABERDING
CLIMATE...HALBACH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
301 AM CST FRI NOV 25 2011
.SHORT TERM...TODAY THROUGH MONDAY
301 AM CST FRI NOV 25 2011
BIG CHANGES COMING OVER THE NEXT FEW DAYS AS RAIN STARTS UP
TONIGHT AHEAD OF A COLD FRONT WHICH WILL KNOCK TEMPERATURES DOWN
ON SATURDAY. BEYOND THIS...THERE IS MUCH UNCERTAINTY FOR SATURDAY
NIGHT INTO SUNDAY WITH WHETHER AN ACCUMULATING SNOW WILL OCCUR.
CURRENTLY...MILD CONDITIONS WERE OBSERVED ACROSS THE REGION DUE
TO GUSTY SOUTH TO SOUTHWEST WINDS AT THE SURFACE AHEAD OF A COLD
FRONT THAT EXTENDS FROM SOUTHWEST ONTARIO THROUGH NORTHERN
MINNESOTA ON INTO CENTRAL SOUTH DAKOTA. FURTHER ALOFT...GENERAL
SOUTHWEST FLOW AHEAD OF TROUGHING DUE TO A NORTHERN AND SOUTHERN
STREAM LOW WAS HELPING TO ADVECT MID TO HIGH LEVEL CLOUDS INTO THE
REGION. AS THE SOUTHERN STREAM TROUGH PROPAGATES EAST INTO THE
SOUTHERN PLAINS THIS MORNING...LOW LEVEL MOISTURE ADVECTION WILL
BE ON THE INCREASE AS A SURFACE LOW DEEPENS ACROSS THE NORTHERN
PLAINS. AS A RESULT...ANOTHER LOW LEVEL STRATUS DECK IS EXPECTED
TO DEVELOP NORTHWARD THIS MORNING FROM THE SOUTHERN PLAINS. THE
LATEST IR SCANS AT 8Z SHOWS THE LEADING EDGE OF THIS STRATUS NEAR
EMPORIA KANSAS...WHICH CORRELATES WELL TO THE 25.07Z RUC
950-900MB LAYER RH. THIS RUN OF THE RUC SHOWS THE HIGHER RH VALUES
INCREASING RAPIDLY THIS MORNING ACROSS THE SOUTHEASTERN HALF OF
IOWA TOWARD THE NORTHERN HALF OF LAKE MICHIGAN BY 18Z TODAY.
25.07Z RUC AND 25.00Z NAM/GFS SOUNDINGS FROM ACROSS THE REGION
SHOW THIS HIGHER RH BEING TRAPPED UNDER A STOUT 900-850MB
INVERSION AND THEREFORE HAVE GONE WITH A MORE PESSIMISTIC CLOUD
FORECAST TODAY. THIS CLOUD COVER WILL LIMIT HOW MUCH WARMING
CAN OCCUR INTO THE AFTERNOON WITH THE HIGHS LIKELY COMING THIS
MORNING.
AFTER THE STRATUS FILLS IN...THE NEXT QUESTION IS WHEN WILL THE
RAIN START UP TONIGHT. 25.00Z NAM AND GFS SOUNDINGS SHOW A DECENT
DRY LAYER CENTERED ON 800MB THAT WILL NEED TO BE OVERCOME FOR ANY
PRECIPITATION TO MAKE IT DOWN TO THE GROUND. BASED ON THESE
SOUNDINGS AND MID LEVEL QG FORCING FIELDS...IT APPEARS THAT THE
DEEP MOISTURE AND FORCING COMES TOGETHER LATER TONIGHT AHEAD OF
THE SURFACE COLD FRONT AND MID LEVEL TROUGH. THE THERMAL PROFILE
WILL BE WARM ENOUGH FOR THIS PRECIPITATION TO BE IN ALL LIQUID
FORM THROUGH SATURDAY MORNING BEFORE THE FRONT COMES THROUGH.
AFTER THE FRONT COMES THROUGH THE REGION SATURDAY MORNING INTO
EARLY SATURDAY AFTERNOON...UNCERTAINTY TAKES OVER WITH WHAT WILL
OCCUR SATURDAY NIGHT INTO SUNDAY. THE ONE THING THAT APPEARS TO
BE CERTAIN IS THAT COLDER AIR WILL ADVECT INTO THE REGION IN THE
LOW LEVELS BRINGING MUCH OF THE THERMAL PROFILE TO BELOW FREEZING
AND SUPPORTIVE OF SNOW BEING THE PRECIPITATION TYPE.
THE MAIN UNCERTAINTY LIES WITH THE DIFFERENCES BETWEEN THE US AND
NON-US MODEL SOLUTIONS WITH THE STRENGTH AND TRACK OF THE TROUGH.
BASED ON INPUT FROM HPC/S MODEL DIAGNOSTICS DESK...THE UNFAVORED
SOLUTION IS THE 25.00Z NAM/GFS AND 24.21Z SREF MEAN WHICH PRODUCE
A DEEPER...CLOSED OFF MID LEVEL LOW WHICH BRINGS THE DEFORMATION
AXIS THROUGH THE HEART OF THE FORECAST AREA. THESE SOLUTIONS WOULD
LIKELY LEAD TO AN ACCUMULATING SNOW ACROSS MUCH OF THE REGION.
THESE MODELS ALSO DEVELOPS A VERY TIGHT PRESSURE GRADIENT IN THE
LOW LEVEL COLD AIR ADVECTION POCKET ON THE SOUTHWEST SIDE OF THE
SURFACE LOW WHICH WOULD BRING GUSTS UP NEAR ADVISORY CRITERIA.
HOWEVER...AT THIS POINT THE FAVORED SOLUTION FOR SATURDAY NIGHT
INTO SUNDAY IS WITH THE 25.00Z ECMWF/UKMET/CANADIAN MODELS. THESE
FORMS OF GUIDANCE ALL SHOW A MUCH LESS AMPLIFIED...OPEN MID LEVEL
WAVE WITH HARDLY ANY SNOW COMING THROUGH SATURDAY NIGHT.
BASED ON THIS INPUT FROM HPC ...HAVE BACKED OFF ON THE PROBABILITY
FOR PRECIPITATION AND THE WIND GUSTS JUST A TAD ON SATURDAY NIGHT.
FOR ADDITIONAL INFORMATION ON THIS FAVORED TREND...PLEASE SEE THE
LATEST PMDHMD FROM HPC.
COLD AIR WILL REMAIN IN PLACE UNTIL MONDAY WHEN A BRIEF SHOT OF
LOW LEVEL WARM AIR ADVECTION COMES THROUGH THE REGION.
.LONG TERM...MONDAY NIGHT THROUGH THURSDAY NIGHT
301 AM CST FRI NOV 25 2011
NOT A WHOLE LOT OF CONFIDENCE GOING INTO THE EXTENDED PERIOD DUE
TO THE ISSUES THIS WEEKEND...BUT HAVE TRENDED TOWARD THE 25.00Z
ECMWF/GEM/UKMET FORECAST WHICH CUT OFF A MID LEVEL LOW ALONG THE
GULF COAST EARLY NEXT WEEK AND SLOWLY BRINGS IT TOWARD THE
NORTHEASTERN US INTO MID WEEK. THIS SETUP WILL KEEP THE REGION IN
A COOL NORTHWESTERLY FLOW ALOFT AND LIMIT ANY KIND OF WARMING
TRENDS. NOT MUCH IN THE WAY OF PRECIPITATION CHANCES EXCEPT FOR AN
OPEN MID LEVEL TROUGH THAT DIVES SOUTHEAST TOWARD THE GREAT LAKES
ON THURSDAY WHICH COULD BRING SOME PRECIPITATION WITH IT.
&&
.AVIATION...THROUGH 06Z SATURDAY
1135 PM CST THU NOV 24 2011
CONCERNS CONTINUE TO BE CENTERED ON LOW LEVEL WIND SHEAR IN THE
NEAR TERM AND THEN STRATUS AFTER 12Z FRIDAY. LOW LEVEL JET
CONTINUES QUITE STRONG WITH THE KARX VAD WIND PROFILE SHOWING 40
TO 50 KNOTS BETWEEN 2K-3K FEET. WITH SURFACE WINDS ONLY AROUND 10
KNOTS AT KLSE HAVE KEPT THE LOW LEVEL WIND SHEAR IN THE FORECAST
THROUGH 15Z FRIDAY AS THE JET THEN DIMINISHES. WINDS CONTINUE TO
GUST TO 25 KNOTS AT KRST AND EXPECT THESE TO CONTINUE THROUGH MUCH
OF THE NIGHT...BUT GRADIENT DOES RELAX AFTER 12Z AND DID DROP THE
GUSTS...BUT SUSTAINED WINDS WILL REMAIN ABOVE 12 KNOTS.
AS FOR THE STRATUS AND CEILINGS HEIGHTS. STRATUS WAS CURRENTLY OVER
OKLAHOMA ADVECTING NORTHWARD. 25.04Z RUC 1000MB-900MB RELATIVE
HUMIDITY PROG HAS A DECENT HANDLE ON THIS MOISTURE...BUT IS A
LITTLE TO FAR NORTH WITH IT INITIALLY. BOTH THE RUC AND THE 25.00Z
NAM BOTH SHOW THIS MOISTURE ADVECTING NORTHWARD...BUT NOT ARRIVING
UNTIL THE 13Z-15Z TIME FRAME. WITH CONSISTENT SIGNAL DID INCLUDE A
BROKEN CEILING AT BOTH TAF SITES...BUT FOR NOW KEPT THEM IN THE
010K-015K FOOT RANGE. NEXT SHIFT SHOULD HAVE A BETTER HANDLE ON
TIMING AND EXTENT OF THESE CLOUDS.
WITH THE COLD FRONT PUSHING CLOSER TO THE AREA BETWEEN 00Z-06Z
SATURDAY...DID MENTION VCSH AT BOTH SITES AFTER 03Z WITH A
CONTINUATION OF THE MVFR CEILINGS.
&&
.CLIMATE...FOR TODAY
301 AM CST FRI NOV 25 2011
RECORD HIGHEST LOWS MAY BE BROKEN TODAY AT BOTH ROCHESTER AND LA
CROSSE WITH TEMPERATURES THIS MORNING FAIRLY MILD IN THE UPPER 40S
TO AROUND 50. THE RECORD HIGHEST LOW TEMPERATURE FOR ROCHESTER
TODAY IS 37 FROM 1915. THE RECORD HIGHEST LOW TEMPERATURE FOR LA
CROSSE TODAY IS 42 IN 1998. FORECAST TEMPERATURES AT MIDNIGHT
TONIGHT ARE EXPECTED TO BE ABOVE THESE VALUES.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
301 AM CST FRI NOV 25 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...RABERDING
CLIMATE...HALBACH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1136 PM CST THU NOV 24 2011
.SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT
236 PM CST THU NOV 24 2011
MAIN FORECAST CONCERNS THIS PACKAGE...RAIN CHANCES FRI NIGHT/SAT...
WINDS SAT...RAIN/SNOW CHANCES SAT NIGHT...TEMPERATURES THRU THE
PERIOD.
DATA ANALYSIS AT 18Z HAD TIGHTER PRESSURE GRADIENT BETWEEN HIGH
PRESSURE OVER THE SOUTHEAST CONUS AND LOW PRESSURE EAST OF LK
WINNIPEG OVER THE AREA. BRISK SOUTH WINDS ACROSS MUCH OF MN/IA/WI AT
MID-DAY. THESE WINDS...COMBINED WITH DIURNAL WARMING AND SOUTHWEST-
WEST FLOW IN THE 925-700MB LAYERS HELPING TO ERODE/ADVECT THE LOW
STRATUS CLOUDS EAST AND OUT OF THE FCST AREA. TEMPS RESPONDING TO
THE WARM ADVECTION/MOSTLY SUNNY SKIES WITH NOONTIME READINGS IN THE
MID 40S TO MID 60S FROM NORTHEAST WI TO SOUTHWEST IA...SOME 10-20F
ABOVE NORMAL AND NEAR RECORD HIGHS AT SOME LOCATIONS ON THIS
THANKSGIVING DAY.
24.12Z MODELS LOOK TO HAVE INITIALIZED WELL AND OFFER RATHER SIMILAR
SOLUTIONS FOR TONIGHT INTO SAT. MODELS GRADUALLY CONVERGING ON A
COMMON/TIGHTER CONSENSUS SOLUTION WITH THE TROUGH/LOW TO MOVE ACROSS
THE REGION FRI NIGHT THRU SAT NIGHT. DPROG/DT OF 500MB HGTS AT
24.12Z SHOWED MODEL RUNS OF 22.12Z AND 23.12Z VERIFIED QUITE WELL
ACROSS NOAM/EASTERN PAC WITH BETTER RUN-TO-RUN CONSISTENCY BY ECMWF.
TREND IS TOWARD A COMPROMISE OF THE EARLIER RUNS. MODELS CONTINUE TO
CONVERGE TOWARD A COMMON SOLUTION TONIGHT THRU SAT AS THE TROUGH/
ENERGY MOVES FROM NEAR THE WEST COAST TO THE WESTERN PLAINS BY 00Z
SAT THEN TO THE MID/UPPER MS VALLEY BY 00Z SUN. TREND GENERALLY
FAVORS THE SLOWER OF THE EARLIER RUNS WITH A COMPROMISE ON THE
STRENGTH OF THE TROUGH. DIFFERENCES REMAIN BETWEEN THE MODELS FOR
SAT NIGHT INTO SUN NIGHT WITH A MORE CONSOLIDATED LOW/TROUGH OVER
THE CENTRAL GREAT LAKES /GFS/NAM/ VS. A MORE NORTHERN/SOUTHERN
STREAM...OPEN TROUGH SPLIT OF THE ENERGY /ECMWF/GEM/UKMET/. GFS
ENSEMBLE MEAN SPLITS THE DIFFERENCE OF THE 2 GROUPS SAT NIGHT/SUN.
ECMWF LOOKS TO HAVE SLIGHTLY BETTER RUN-TO-RUN CONSISTENCY IN THE
LATER PART OF THE SHORT-TERM PERIOD. CHECK OF OBS VS. MODEL DATA AT
18Z SHOWED MODELS ALL REASONABLE WITH THE SFC MASS FIELDS OVER THE
CENTRAL CONUS. PER WV IMAGERY...ALL APPEARED REASONABLE WITH THE
SHORTWAVE DETAILS OVER NOAM/EASTERN PAC. THUS AGAIN NO CLEAR
DETERMINISTIC MODEL FAVORITE. WITH THE TRENDS TOWARD A COMPROMISE
SOLUTION...AT LEAST THRU 60HRS...FAVORED THE MODEL/ENSEMBLE
COMPROMISE SOLUTION. GIVEN THE CONTINUED DETAIL DIFFERENCES...SHORT-
TERM FCST CONFIDENCE AVERAGE AT BEST THIS CYCLE.
IN THE SHORT TERM...FIRST CONCERN IS RETURN OF MOISTURE IN 950-900MB
LAYER TONIGHT AND IF IT WILL MANIFEST AS ANOTHER LOW STRATUS DECK
OR NOT. SEE AVIATION DISCUSSION BELOW FOR MORE DETAILS ON POTENTIAL
LOW CLOUDS/BR TONIGHT AS THE LOWER LEVEL MOISTURE RETURNS. DID SHOW
INCREASING CLOUDS IN THE GRIDS LATER TONIGHT AS MOISTURE/BROAD LIFT
ABOVE 500MB AHEAD OF THE TROUGH ADVANCING THRU THE ROCKIES INCREASE
OVER THE AREA. BRISK WINDS TONIGHT AND THESE CLOUDS TO MAKE FOR A
SEASONABLY MILD NIGHT ACROSS THE AREA TONIGHT...WITH LOWS ABOVE THE
NORMAL HIGHS FOR THE DATE. MOISTURE/LIFT CONTINUE TO INCREASE OVER
THE AREA FRI WITH THICKENING CLOUDS. QUESTION REMAINS WILL A SMALL
-RA CHANCE BE NEEDED ACROSS THE SOUTH END OF THE FCST AREA LATE IN
THE AFTERNOON. MODELS MAINTAIN A DRY LAYER BETWEEN 850-650MB OVER
THE SOUTH END OF THE FCST AREA FRI AFTERNOON...WITH MODEST LIFT AT
BEST AT OR ABOVE 500MB. WILL MAINTAIN THE DRY FRI AFTERNOON FCST FOR
NOW. MOISTURE/850-500MB THERMO-DYNAMIC FORCING/LIFT INCREASE QUICKLY
FRI EVENING...MAXIMIZING OVER THE FCST AREA LATE FRI NIGHT INTO
EARLY SAT MORNING. THIS WITH INCREASING 500-300MB PV ADVECTION AND
300MB AGEOSTROPHIC FLOW/DIVERGENCE IN RIGHT ENTRANCE REGION OF A
110KT JET AHEAD OF THE TROUGH AXIS. PW VALUES INCREASE INTO THE 0.75
TO 1 INCH RANGE OVER THE SOUTHEAST 3/4 OF THE FCST AREA AS WELL BY
12Z SAT. THUS RAISED RAIN CHANCE THRU FRI NIGHT...INTO THE 60-85
PERCENT RANGE AFTER MIDNIGHT. RAISED RAIN CHANCES SAT MORNING INTO
THE 60-80 PERCENT RANGE OVER THE EAST HALF OF THE FCST AREA. LEFT
RAIN CHANCES IN THE 30-50 PERCENT RANGE OVER THE WEST THIRD OF THE
FCST AREA SAT MORNING AS BETTER CONSENSUS FOR THE COLD FRONT AND
925-850MB TROUGH AXIS TO BE MOVING EAST OF THE MS RIVER DURING THE
MORNING. DRIER AIR AND COLD ADVECTION/SUBSIDENCE TO BE SPREADING
INTO THE AREA BEHIND THE SFC-850MB FRONT. QUESTION FOR SAT
AFTERNOON BECOMES HOW QUICKLY WILL THE COLUMN COOL ENOUGH FOR ANY
PRECIP TO MIX WITH/CHANGE TO SNOW. NAM MOST ROBUST BRINGING IN THE
COLD AIR. TEMPS DO FALL DURING THE DAY SAT IN THE STRONG POST
FRONTAL COLD ADVECTION BUT MODEL CONSENSUS KEEPS THE BOUNDARY LAYER
TEMPS DURING THE AFTERNOON IN THE UPPER 30S/AROUND 40. THIS A BIT
WARM FOR A COMPLETE CHANGE TO -SN OR ACCUMULATIONS...GIVEN BULK OF
FORCING/LIFT IS NORTH/EAST OF THE AREA AND PRECIP RATES EXPECTED TO
BE ON THE LIGHT SIDE BY SAT AFTERNOON. CONTINUED A -RA/-SN MIX FOR
MUCH OF THE AREA SAT AFTERNOON. STRONGEST OF SFC-850MB COLD
ADVECTION MOVES ACROSS THE AREA SAT MORNING WHILE STRONGEST OF SFC-
925MB GRADIENT WINDS MOVE ACROSS THE AREA CENTERED ON SAT NIGHT.
STRONG/GUSTY NORTHWEST WINDS TO SPREAD ACROSS THE AREA SAT/SAT NIGHT
BUT AT THIS TIME LOOK TO REMAIN BELOW ADVISORY CRITERIA. DID
INCREASE WINDS SAT NIGHT INTO SUN WITH GRADIENT REMAINING TIGHT AND
CONTINUING LOW LEVEL COLD ADVECTION OVER THE AREA. BOUNDARY LAYER
COOLS ENOUGH FOR ALL SNOW SAT EVENING. NAM/GFS SHOWING MORE WRAP
AROUND/DEFORMATION BAND PRECIP ON THE BACK SIDE OF THE SYSTEM WITH A
500MB LOW OVER EASTERN WI/LK MI WHILE MORE OPEN/POSITIVE TILT WAVE
SOLUTION OF ECMWF/GEM/UKMET MUCH WEAKER WITH FORCING/LIFT/PRECIP
PRODUCTION BEHIND THE TROUGH AXIS SAT NIGHT/SUN MORNING. LEFT BULK
OF -SN/-RA CHANCES SAT NIGHT IN THE 20-50 PERCENT RANGE FOR NOW...
ONLY CARRYING LIKELY ALONG/NORTH OF HIGHWAY 29 ACROSS CENTRAL WI.
DID LINGER A 20 PERCENT -SN CHANCE OVER THE EAST HALF OF THE FCST
AREA SUN MORNING TO HONOR NAM/GFS SOLUTIONS. HIGH PRESSURE/SHORTWAVE
RIDGING ALOFT BUILD IN FOR LATER SUN/SUN NIGHT.
FAVORED A BLEND OF THE NUMERICAL TEMP GUIDANCE FOR MOST LOWS/HIGHS
TONIGHT THRU SUN NIGHT. DID FAVOR WARMER OF GUIDANCE LOWS TONIGHT
WITH BRISK SOUTH WINDS AND INCREASE OF HIGH CLOUDS AFTER MIDNIGHT.
CONTINUED THE TREND OF HIGHS SAT AROUND 15Z THEN FALLING TEMPS
BEHIND THE COLD FRONT THE REST OF THE DAY. WITH SFC RIDGE AXIS OVER
THE AREA SUN NIGHT FAVORED COOLER OF GUIDANCE LOWS.
.LONG TERM...MONDAY THROUGH THURSDAY
236 PM CST THU NOV 24 2011
24.00Z MEDIUM RANGE MODELS SHOW QUITE A BIT OF VARIABILITY ALREADY
MONDAY WITH THE PROGRESSIVENESS OF THE TROUGHING OVER THE EASTERN
CONUS. RUN-TO-RUN CONSISTENCY LEAVES QUITE A BIT TO BE DESIRED TOO.
MODELS BETTER/MORE CONSISTENT WITH THE NEXT TROUGH DROPPING INTO
THE NORTHERN PLAINS BUT TREND IS A BIT FLATTER/FASTER WITH THIS
FEATURE. MODELS REMAIN FASTER/FLATTER WITH THIS FEATURE TUE WITH A
TREND TOWARD MORE ZONAL FLOW OVER THE NORTH-CENTRAL AND NORTHWEST
CONUS. STILL PLENTY OF DIFFERENCES WITH EAST/SOUTHEAST CONUS LOW.
GFS/ECMWF SOLUTIONS DIVERGE FOR WED WITH TIMING ISSUES OF A
STRONGER SHORTWAVE THRU BROAD NORTHWEST FLOW OVER WESTERN NOAM.
SOLUTIONS TREND MORE SIMILAR WITH A SHORTWAVE TROUGH MOVING ACROSS
THE WESTERN GREAT LAKES THU. RUN-TO-RUN CONSISTENCY REMAINS BELOW
AVERAGE WED/THU...TIED TO GLOBAL FLOW FORCING MECHANISMS AS
DISCUSSED BY MID SHIFT FORECASTER. UNTIL THIS SETTLES DOWN...RUN-TO-
RUN CONSISTENCY BEYOND ABOUT DAY 5 CAN BE EXPECTED TO REMAIN BELOW
AVERAGE. LONG-TERM FCST CONFIDENCE AGAIN BELOW AVERAGE WITH ALL THE
BETWEEN MODEL AND RUN-TO-RUN VARIABILITY...THUS WILL LEAVE DAY 4-7
GRIDS CLOSE TO A THE MODEL/ENSEMBLE CONSENSUS. WITH A DRIER WEST TO
NORTHWEST FLOW ALOFT AND MAIN SHORTWAVE ENERGY LOOKING TO PASS NORTH
OF THE AREA...DAYS 4-7 TRENDING TO BE A MOSTLY DRY PERIOD.
REASONABLE MODEL CONSENSUS FOR A FRONT TO PUSH ACROSS THE AREA MON
BUT MOISTURE LIMITED AND SFC FRONT PASSES WELL AHEAD OF THE MID
LEVEL TROUGH. CONSENSUS FOR SFC HIGH PRESSURE TO BUILD OVER THE
REGION FOR TUE. MAIN SHORTWAVE ENERGY WED OR THU /DEPENDS ON WHICH
MODEL WOULD BE MORE CORRECT WITH TIMING/ PASSES NORTH OF THE AREA
WITH ANOTHER FRONT TO PUSH ACROSS THE UPPER MIDWEST ONE OF THE DAYS.
24.12Z GFS/ECMWF PUSH A STRONGER TROUGH/FRONT TOWARD/ACROSS THE
REGION THU...WITH A SMALL -RA/-SN CHANCE THAT DAY REASONABLE FOR
NOW. TEMPERATURES FOR DAYS 4-7 LOOKING TO BE NEAR/A BIT ABOVE NORMAL
AND THIS WELL TRENDED WITH THE MODEL CONSENSUS GRIDS.
&&
.AVIATION...THROUGH 06Z SATURDAY
1135 PM CST THU NOV 24 2011
CONCERNS CONTINUE TO BE CENTERED ON LOW LEVEL WIND SHEAR IN THE
NEAR TERM AND THEN STRATUS AFTER 12Z FRIDAY. LOW LEVEL JET
CONTINUES QUITE STRONG WITH THE KARX VAD WIND PROFILE SHOWING 40
TO 50 KNOTS BETWEEN 2K-3K FEET. WITH SURFACE WINDS ONLY AROUND 10
KNOTS AT KLSE HAVE KEPT THE LOW LEVEL WIND SHEAR IN THE FORECAST
THROUGH 15Z FRIDAY AS THE JET THEN DIMINISHES. WINDS CONTINUE TO
GUST TO 25 KNOTS AT KRST AND EXPECT THESE TO CONTINUE THROUGH MUCH
OF THE NIGHT...BUT GRADIENT DOES RELAX AFTER 12Z AND DID DROP THE
GUSTS...BUT SUSTAINED WINDS WILL REMAIN ABOVE 12 KNOTS.
AS FOR THE STRATUS AND CEILINGS HEIGHTS. STRATUS WAS CURRENTLY OVER
OKLAHOMA ADVECTING NORTHWARD. 25.04Z RUC 1000MB-900MB RELATIVE
HUMIDITY PROG HAS A DECENT HANDLE ON THIS MOISTURE...BUT IS A
LITTLE TO FAR NORTH WITH IT INITIALLY. BOTH THE RUC AND THE 25.00Z
NAM BOTH SHOW THIS MOISTURE ADVECTING NORTHWARD...BUT NOT ARRIVING
UNTIL THE 13Z-15Z TIME FRAME. WITH CONSISTENT SIGNAL DID INCLUDE A
BROKEN CEILING AT BOTH TAF SITES...BUT FOR NOW KEPT THEM IN THE
010K-015K FOOT RANGE. NEXT SHIFT SHOULD HAVE A BETTER HANDLE ON
TIMING AND EXTENT OF THESE CLOUDS.
WITH THE COLD FRONT PUSHING CLOSER TO THE AREA BETWEEN 00Z-06Z
SATURDAY...DID MENTION VCSH AT BOTH SITES AFTER 03Z WITH A
CONTINUATION OF THE MVFR CEILINGS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
236 PM CST THU NOV 24 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1130 PM CST SAT NOV 26 2011
.UPDATE 27/06Z AVIATION DISCUSSION...
.SHORT TERM /TONIGHT/...
WIND ADVISORY DROPPED AT 9 PM...BUT WINDS WILL REMAIN BRISK
OVERNIGHT. CLOUDS TO HOLD ON AS WELL. RAISED MINS A BIT OVER THE
REGION WITH CLOUDS AND MIXING HOLDING ON.
.PREVIOUS SHORT TERM /TONIGHT/...
MAIN CONCERN TONIGHT WILL BE TEMP AND WIND TRENDS...AND PRECIP TO A
LESSER EXTENT. PRIMARY PRECIP SHIELD ASSOCIATED WITH CENTRAL CONUS
LONG WAVE TROUGH CURRENTLY EXTENDS FROM SRN PLAINS INTO GREAT LAKES
AND HAS ALL BUT EXITED FORECAST AREA. FORCING WITH THIS IS MAINLY
MID/UPPER LEVEL BASED IN THE FORM OF DPVA AND RIGHT ENTRANCE REGION
DIVERGENCE OF GREAT LAKES JET SEGMENT. RADAR AND SATELLITE TRENDS
DO NOT LOOK PROMISING FOR ADDITIONAL PRECIP THIS EVENING...HOWEVER
MODELS DO SUSTAIN SOME MID LEVEL KINEMATIC FORCING WITH BRIEF SURGE
OF DEEPER MOISTURE SWINGING THROUGH AROUND 00Z OR SHORTLY
THEREAFTER. THUS HAVE KEPT MENTION OF SPRINKLES OR FLURRIES NE
THIRD DURING THE EVENING.
POTENTIAL FOR ADVISORY LEVEL WINDS HAS DECREASED AS WELL...BOTH
SPATIALLY AND TEMPORALLY...WITH ONLY A SITE OR TWO WEST CURRENTLY
VERIFYING. ISALLOBARIC MAX...MAX MSLP GRADIENT...AND MAGNITUDE OF
MIXED LAYER WINDS ALL DECREASE THIS EVENING AS THEY APPROACH THE MO
RIVER SO DO NOT EXPECT ADVISORY CRITERIA WINDS TO CONTINUE AS LONG
OR AS FAR EAST AS PREVIOUSLY ANTICIPATED. THUS HEADLINE NOW ENDS AT
03Z WITH SEVERAL TIERS OF ERN COUNTIES REMOVED.
OUTSIDE OF THE RUC...RAW MODEL TEMPS ARE BEHIND THE CURVE IN TERMS
OF COOLING. HOWEVER EVEN THE COOLER NAM WHICH EVENTUALLY CATCHES UP
TO THE RUC SUGGESTS CLOUDS AND WINDS KEEPING TEMPS ABOVE GUIDANCE.
.LONG TERM /SUNDAY THROUGH SATURDAY/...
IN THE LONG TERM...IT WILL BE FAIRLY QUIET WITH A DRY FORECAST
THROUGH DAY SEVEN. UPPER LEVEL LOW PRESSURE SYSTEM FORECAST BY ALL
MODELS OVER THE SOUTHEAST UNITED STATES HEADS NORTH INTO THE OHIO
VALLEY BY TUESDAY. MEANWHILE...A WEAK NORTHERN STREAM SHORTWAVE
SHOULD CROSS THE NORTHERN PLAINS AND UPPER MIDWEST. UPSTREAM QG
FORCING OVER THE NORTHERN PLAINS SHOULD WEAKEN AS THE WAVE
APPROACHES THE MISSISSIPPI VALLEY AND INTERACTS WITH UPPER LOW
MOVING NORTH INTO THE OHIO VALLEY. THE LACK OF SUSTAINED VERTICAL
MOTION AND LIMITED MOISTURE SHOULD KEEP THE ASSOCIATED COLD FRONT
DRY WITH SOME CLOUDS AS IT CROSSES IOWA. ON MONDAY...AHEAD OF THE
FRONT...WEAK HIGH PRESSURE OVER CENTRAL IOWA BETWEEN THE SYSTEM OVER
THE OHIO VALLEY AND THE APPROACHING COLD FRONT. ONLY MODEST MIXING
SHOULD KEEP TEMPERATURES RELATIVELY COOL CONSIDERING THE THERMAL
CHARACTERISTICS OF THE AIRMASS. GIVEN THE EXPECTED COOL TEMPERATURES
ON MONDAY...ONLY MODEST COOLING IS FORECAST BEHIND THE FRONT ON
TUESDAY. THIS IS PROBABLY DUE TO BETTER MIXING EVEN THOUGH THE
AIRMASS WILL BE COOLER.
MODELS AGREE IN DIGGING AN UPPER LOW OVER THE SOUTHWEST UNITED
STATES DURING THE EXTENDED. THE 12Z ECMWF/GFS SUGGEST NORTHWEST
FLOW OVER THE NORTH CENTRAL UNITED STATES BUT THEY HAVE TIMING
DIFFERENCES WITH SHORTWAVES AND FRONTAL PASSAGES LATE NEXT WEEK.
ALTHOUGH ALL SOLUTIONS LOOK MAINLY DRY FOR CENTRAL IOWA...DAY TO DAY
TEMPERATURE FORECASTS HAVE ONLY MODEST CONFIDENCE AT THIS POINT.
&&
.AVIATION...27/06Z
MAIN FOCUS ON STRATUS AND WINDS OVERNIGHT. WINDS WILL REMAIN BRISK
WITH NW 20 TO 30 GUST 40 MPH AT TIMES. STRATUS IN THE MVFR CATEGORY
WITH EASTERN AREAS SEEING CIGS JUST AT OR UNDER 2000` AT TIMES
THROUGH 12Z. EXPECT PBL CLOUDS TO LIFT AFT 15Z SUNDAY WITH SCT-BKN
GIVING WAY TO VFR CIGS AFT 16-19Z EAST. WINDS TO RELAX AND REMAIN
LIGHT FROM 00Z THROUGH END OF FORECAST PERIOD.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE
&&
$$
SHORT TERM...SMALL/REV
LONG TERM...JOHNSON
AVIATION...REV
AREA FORECAST DISCUSSION
NWS GOODLAND KS
220 AM MST SUN NOV 27 2011
.SHORT TERM (TODAY-TUESDAY)...
220 AM MST SUN NOV 27 2011
EARLY MORNING WV IMAGERY AND RUC H5 ANALYSIS SHOW UPPER LEVEL
PATTERN DOMINATED BY HIGHLY AMPLIFIED RIDGE-TROUGH PATTERN. H5
RIDGE CURRENTLY CENTERED OFF SOUTHERN CALIFORNIA COAST...WITH AXIS
EXTENDING NORTH TO SASKATCHEWAN CANADA. TROUGH AXIS CURRENTLY
EXTENDS FROM WESTERN GREAT LAKES REGION TO SOUTHERN TEXAS. BETWEEN
THESE FEATURES NORTHERLY FLOW AND LARGE SCALE SUBSIDENCE IS IN
PLACES ACROSS PLAINS.
H5 RIDGE WILL DOMINATE PATTERN OVER CWA THROUGH MON...WITH MILD
TEMPS AND DRY CONDITIONS EXPECTED. SHORTWAVE TROUGH PASSES OVER
CWA MONDAY NIGHT...WITH ASSOCIATED COLD FRONT MOVING THROUGH
DURING 18-00Z TIME PERIOD. SHOULD SEE DECENT WARMING AHEAD OF
FRONTAL PASSAGE WITH HIGHS WARMING TO NEAR 60 OVER MOST OF CWA
MIDDAY MONDAY...AND TO MID 60S ACROSS SOUTHERN EXTENT OF CWA.
WHILE GUIDANCE SHOWS TD VALUES INCREASING AHEAD OF FROPA TO LOW
20S...RH VALUES NEAR 18-20% STILL FORECAST ACROSS SOUTHERN PART OF
CWA. WITH GUSTY WINDS DEVELOPING DURING THE AFTERNOON...COULD SEE
A BRIEF WINDOW OF OVERLAP OF NEAR RED FLAG CONDITIONS BEFORE RH
VALUES INCREASE. LOOKS MARGINAL...SO NOT PLANNING ANY HIGHLIGHTS
THIS FORECAST CYCLE.
COULDNT RULE OUT A FEW SPRINKLES/FLURRIES DURING A BRIEF WINDOW
MONDAY NIGHT. HOWEVER...DUE TO THE PROGRESSIVE NATURE OF THIS WAVE
SUBSIDENCE WILL BE QUICK TO BUILD BACK OVER CWA...AND LARGE SCALE
ACSENT IS SOUTHEAST OF CWA BY TIME GUIDANCE SHOWS MID LEVELS
SATURATING. WILL KEEP MENTION OUT OF FORECAST FOR NOW.
SHORTWAVE RIDGING QUICKLY BUILDS BACK OVER CWA BEHIND DEPARTING
TROUGH...WITH DRY CONDITIONS AND SEASONAL TEMPS IN THE MID-UPPER
40S ON TUESDAY.
DR
.LONG TERM (WEDNESDAY-SATURDAY)...
220 AM MST SUN NOV 27 2011
THE UPPER LEVEL RIDGE WILL REMAIN OVER THE CWA WEDNESDAY BEFORE THE
UPPER LEVEL FLOW TRANSITIONS TO MORE OF A SPLIT FLOW PATTERN
THURSDAY THROUGH SATURDAY...WITH A CLOSED LOW OVER THE WESTERN CONUS
AND AN UPPER LEVEL TROUGH OVER THE NORTH AND NORTHEAST CONUS.
MODELS ARE COMING INTO BETTER AGREEMENT WITH THE SPLIT FLOW PATTERN
AND THE FRONTAL TIMING FOR THURSDAY. CURRENTLY THE STRONG COLD
FRONT LOOKS TO MOVE THROUGH DURING THE OVERNIGHT OR EARLY MORNING
HOURS. MODELS CONTINUE TO SHOW PRECIP. AND WINDY CONDITIONS BEHIND
THE FRONT THURSDAY. HOWEVER MOST OF THE PRECIP. AND FORCING IS
DEPICTED WEST OF THE CWA.
FROM FRIDAY THROUGH THE WEEKEND THE MODELS ARE MUCH LESS
CONFIDENT WITH THE UPPER LEVEL FLOW. GENERALLY THE CLOSED LOW OVER
THE SOUTHWEST CONUS MERGES WITH AN UPPER LEVEL TROUGH THAT MOVES
DOWN FROM CANADA DURING THE WEEKEND. THE PLACEMENT OF THE UPPER
LEVEL FEATURES ONCE THE CLOSED LOW IS ABSORBED INTO THE MAIN FLOW IS
STILL IN QUESTION. GENERALLY THE CLOSED LOW WILL MERGE WITH THE
MAIN FLOW OVER THE WESTERN HIGH PLAINS...PLACING AN UPPER LEVEL
TROUGH OVER THE CENTRAL CONUS. AHEAD OF THE UPPER LEVEL TROUGH
ANOTHER COLD FRONT WILL MOVE THROUGH THE CWA. NOT TOO CONFIDENT
WITH PRECIP. CHANCES BEHIND THE FRONT AS THIS WILL DEPEND ON
WHETHER THE UPPER LEVEL FLOW WILL MERGE BEFORE MOVING OVER THE CWA
SENDING MOISTURE OUR WAY...OR REMAIN SPLIT WHICH WOULD SEND THE
MOISTURE TO OUR NORTH AND SOUTH.
TEMPERATURES THROUGH THE PERIOD WILL BE WARMEST ON WEDNESDAY BEFORE
THE COLD FRONT MOVES THROUGH. THROUGH THE REST OF THE WEEK
TEMPERATURES WILL BE ROUGHLY 10 DEGREES BELOW NORMAL AS THE COLD AIR
REMAINS OVER THE CWA. A BRIEF WARM UP WILL OCCUR SATURDAY...WITH
NEAR NORMAL TEMPERATURES BEFORE THE NEXT COLD FRONT MOVES
THROUGH.
JTL
&&
.AVIATION...
940 PM MST SAT NOV 26 2011
FOR THE 06Z TAFS...VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD.
WINDS WILL BE LIGHT AND NORTHWESTERLY UNDER CLEAR SKIES AS HIGH
PRESSURE BUILDS OVER THE REGION.
CJS
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
442 AM EST SUN NOV 27 2011
.SYNOPSIS...
WV IMAGERY AND RUC ANALYSIS INDICATED A HIGH AMPLITUDE PATTERN WITH
A MID/UPPER LEVEL RIDGE OVER THE WRN CONUS AND A TROUGH OVER THE
CNTRL CONUS FROM NW ONTARIO TO CNTRL TX. THE BACK EDGE OF THE DEEPER
MOISTURE WAS MOVING STEADILY EASTWARD AND WAS NEAR A INL-MSP LINE.
AT THE SFC...LOW PRES NE OF LAKE SUPERIOR CONTINUED TO LIFT OFF TO
THE NE THROUGH NRN ONTARIO. CAA IN THE WAKE OF THE LOW HAD DROPPED
850 MB TEMPS TO NEAR -10C OVER WRN LAKE SUPERIOR. EVEN THOUGH
KINL/CYPL SOUNDINGS INDICATED A MOISTURE PROFILE THROUGH LOW AND MID
LEVELS FAVORABLE FOR LAKE EFFECT SNOW...WITH ONLY MARGINAL
INSTABILITY (LK-H8 DELTA/T TO 15C)AND THE CLOUD LAYER BLO THE DGZ
LAYER (10K-14K FT) SNOW HAS BEEN RELATIVELY LIGHT. BRIEF PERIODS OF
LAKE ENHANCED SNOW AT IWD AND AT NWS MQT HAVE RESULTED IN A LIGHT
COATING OF SNOW. IR LOOP SHOWED THE BACK EDGE OF THE LOW CLOUDS TO
NEAR THE MN/DAKOTAS BORDER.
&&
.DISCUSSION...
TODAY AND TONIGHT...EXPECT SCT/NMRS LIGHT LAKE EFFECT SNOW SHOWERS TO
CONTINUE FOR LOCATIONS FAVORED BY NNW FLOW. THE RELATIVELY SHORT
FETCH LENGTH INTO THE WEST WILL LIMIT ACCUMULATION POTENTIAL.
THE LOCAL HIGH RES WRF/ARW SUGGESTS THAT UPSTREAM CONDITIONING FROM
LAKE NIPIGON AND SLIGHTLY MORE N THAN NNW FLOW MAY SUPPORT LES BANDS
INTO NORTH CENTRAL UPPER MI. THE LATER ARRIVAL OF THE COLD AIR
INTO THE EAST TIL THE AFTER THE MOISTURE DEPARTS WILL ALSO BE
UNFAVORABLE FOR ANY SIGNIFICANT ACCUMULATIONS. THE LES SHOULD
DIMINISH DURING THE AFTERNOON AS 800-700 MB DRYING MOVE IN.
OVERALL...GIVEN THE LACK OF SYNOPTIC SCALE UPWARD MOTION WITH THE
MARGINAL INSTABILITY...ONLY MINOR ACCUMULATIONS OF AN INCH OR LESS
ARE EXPECTED.
TONIGHT...ANY REMAINING LES WILL GRADUALLY END AS SFC AND MID LEVEL
RIDGING BUILD INTO THE THE REGION WITH ACYC FLOW AND INVERSION
HEIGHTS FALLING TO AROUND 3K FT. WITH FAVORABLE RADIATIONAL COOLING
CONDITIONS INLAND OVERNIGHT...MIN TEMPS WILL FALL INTO THE MID TEENS
WHILE LAKE CLOUDS KEEP TEMPS INT THE MID 20S EAST.
MONDAY INTO TUE...MDLS WERE IN REASONABLE AGREEMENT WITH A NRN
STREAM SHORTWAVE TROUGH MOVING INTO MANITOBA MON AND THROUGH NRN
ONTARIO EARLY TUE WHICH WILL DRAG A COLD FRONT THROUGH LAKE
SUPERIOR. WITH LITTLE MOISTURE AVAILABLE ONLY WEAK DYNAMICS ON
THE SRN TAIL OF THE SHRTWV...NO MEASURABLE PCPN IS EXPECTED. WITH SW
LOW LEVEL WAA AND SUNSHINE AHEAD OF THE TROUGH ON MON...TEMPS WILL
REBOUND INTO THE UPPER 30S TO AROUND 40. WITH ONLY MODERATE CAA
BEHIND THE FRONT AND A RELATIVELY DRY AIRMASS 850 MB TEMPS TO AROUND
-6C WILL NOT BE LOW ENOUGH TO PRODUCE LES. PCPN ASSOCIATED WITH THE
CUTOFF LOW ALSO WILL REMAIN EAST OF THE AREA TUE AS DRY NRLY FLOW
(PWAT DOWN TO NEAR 0.10 INCH) DOMINATES THE AREA.
WED THROUGH SAT...THE GFS/ECMWF/GEM WERE CONSISTENT IN SHOWING TREND
TOWARD TROUGHING INTO THE CNTRL CONUS AS A RIDGE BUILDS OVER THE ERN
PACIFIC. WITH THIS PATTERN...COLDER WILL MOVE INTO THE GREAT LAKES
WITH POTENTIAL FOR SOME LES. TIMING IS UNCERTAIN...BUT GFS/ECMWF
CONSENSUS SUGGESTS THAT A SHORTWAVE WILL MOVE THROUGH THU WITH 850 MB
TEMPS FALLING TO NEAR -13C BY LATE THU INTO THU NIGHT. EVEN THOUGH
THIS SHOULD PROVIDE ENOUGH INSTABILITY FOR LES...FCST DRY 850-700 MB
MOISTURE WILL BE UNFAVORABLE FOR SIGNIFICANT ACCUMULATIONS. A
PROGRESSIVE NRN STREAM FLOW WOULD LEAD TO WAA FRI INTO SAT WITH
RECOVERING TEMPS AND MAINLY DRY WEATHER. &&
.AVIATION /FOR THE 06Z TAF ISSUANCE/...
LOW PRESSURE OVER EASTERN LAKE SUPERIOR WILL CONTINUE TO LIFT NE
REACHING ONTARIO LATER TONIGHT. THE ADVECTION OF COLDER/DRIER LOW
LEVEL AIR INTO THE AREA IN THE WAKE OF THIS SYSTEM SHOULD ALLOW FOR
SLOW IMPROVEMENT TO MVFR CONDITIONS AT ALL SITES LATER TONIGHT INTO
SUNDAY. THE COLDER AIR WILL ALSO CAUSE ANY LIGHT RAIN TO CHANGE OVER
SNOW OVERNIGHT AT KCMX AND KIWD. INCREASED MIXING WILL ALLOW N-NW
WINDS TO GUST AOA 25 KTS AT TIMES ON SUNDAY.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
EXPECT N TO NW WINDS UP TO 30 KTS WITH A FEW GALE FORCE GUSTS TO 35
KTS TO DIMINISH THIS AFTERNOON WITH THE APPROACH OF HI PRES FROM
MINNESOTA. LIGHT WINDS TONIGHT WITH THE PASSAGE OF THE HI WILL GIVE
WAY TO A STRONGER SW FLOW ON MON AS THE PRES GRADIENT SHARPENS
BETWEEN THE HI DRIFTING INTO THE LOWER LAKES AND ANOTHER APPROACHING
COLD FRONT. LOOK FOR A WSHFT TO THE N BEHIND THIS FRONT ON MON NIGHT
AND STRENGTHENING WINDS MAINLY OVER THE E HALF INTO TUE ON THE NW
FLANK OF A DEEP LO PRES MOVING THRU THE LOWER GREAT LAKES INTO
ONTARIO. DEPENDING ON HOW FAR W THIS LO DRIFTS...N GALES TO 35 KTS
ARE POSSIBLE OVER PORTIONS OF THE E HALF. THE STRONGER WINDS WILL
DIMINISH TUE NIGHT THRU WED WITH THE APPROACH OF ANOTHER HI PRES
SYSTEM...BUT A STRONGER NW FLOW WILL DEVELOP ON THU IN THE WAKE OF
ANOTHER COLD FROPA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
DISCUSSION...JLB
AVIATION...VOSS
MARINE...KC
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
311 AM CST Sun Nov 27 2011
.DISCUSSION...
Main challenges for the next few days will be temperatures with an
upper pattern that remains fairly complex across the CONUS.
Today - Tonight:
Temperatures today will likely be slow to recover from their minimal
diurnal range due to cloud cover from moisture trapped underneath a
slow moving upper wave. Low to mid level stratus should hang on
across the area through the mid to late morning hours and then
begin to shift east with the axis of the upper wave, allowing
stronger subsidence and drier air can move in and help to clear
things out. Couple the slower retreat of cloud cover with continued
northerly/northwesterly winds advecting slightly cooler air and
temperatures today look to be stuck in the lower 40s/near 40 for most
areas.
For tonight, skies are expected to clear out with a weak surface
ridge nosing into northwestern Missouri. With dewpoints likely to
fall into the teens overnight, decent radiational cooling should
occur and parts of far northwestern Missouri should be able to fall
into the mid to upper teens. Elsewhere across the forecast area,
winds that don`t completely go calm may keep the boundary layer
mixed enough to keep lows in the low to mid 20s.
Monday - Tuesday:
The upper low will continue to spin to our south and east as another
wave begins to move southeast out of the northern Rockies and Plains
Monday evening/night. With this wave moving through the upper ridge
it leads to a brief raising of thicknesses and heights across the
area. This should allow for temperatures to warm back to more
seasonal readings, especially across the western forecast area. High
temperatures will range from the upper 40s across our west to the
lower 40s in our east as result. This secondary wave will send a
reinforcing shot of cooler air into the region. Fortunately the
airmasses associated with these recent waves have been of a maritime
origin and as a result we really only cool back down into the
lower 40s for Tuesday.
Wednesday - Saturday:
Another wave will move overtop the eastern Pacific upper ridge
Wednesday and Thursday. Models are actually somewhat consistent in
breaking this wave apart and sending the northern portion across the
Great Lakes and pinching off the southern portion into the
Southwestern CONUS. This pretty much leaves our area dry, although
we may see increased cloud cover as there is fair amount of
vorticity that remains between the two main waves. Strong maritime
high pressure reinforces the airmass already in place and as a
result we continue to see a good likelihood of below normal
temperatures through the end of the week. By Saturday however, that
high pressure should have moved to our southeast with winds
returning to southerly/southwesterly direction. This should result
in another modest warm with temperatures returning to near seasonal
levels by Saturday afternoon.
CDB
&&
.AVIATION...
There has been no net eastward movement to the VFR stratus deck this
evening as deep cyclonic flow persists ahead of elongated upper
trough axis. Based on RUC 875mb RH progs, have pushed back clearing
all the way until 15Z.
Winds will remain gusty from the north-northwest, peaking at 25 to
30 knots for the next several hours with only the slightest of
diminishing trends through the day with a general 15G25KT character.
Winds will rapidly diminish between 23 and 00Z with sunset and a
building high pressure ridge.
Bookbinder
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1124 PM CST SAT NOV 26 2011
...UPDATED AVIATION DISCUSSION...
.DISCUSSION...
Short Range (Tonight through Monday)...
Radar and surface observations this afternoon show that the cold
front, that was moving through the region this morning, has cleared
the eastern boundary of our forecast area, with showers still
lingering across central Missouri. The cooler air behind the front
did not waste anytime surging south, as temperatures have continued
to wallow around in the 40s across the region this afternoon. Cloud
cover has been slow to clear behind the front due to the amount of
moisture trapped in the base of the parent trough that is the driving
force behind the cold front. Despite clear skies in central Kansas,
thoughts are that we will have to wait till sometime Sunday morning
for clouds to begin clearing out given the progress of the trough.
Conditions Sunday will be more typical of late November weather than
what we experienced over the past work week. The cooler air behind
the front will stay in place across the region even as the clouds
clear. Pressure gradient wind, and boundary layer mixing after
sunrise Sunday, will keep winds rather gusty through much of the
day. The breezy conditions should abate by the evening hours as a
surface ridge slides east across Kansas and Missouri, allowing the
wind to go light and variable late Sunday night into Monday morning.
Have pushed Sunday night/Monday morning lows down as a result as
guidance numbers look too warm given clear skies, light winds, and
forecast 850mb temperatures around -2C.
For the rest of Monday, the trough that moved through earlier this
weekend will have bombed out into a cutoff low across the lower half
of the Mississippi River Valley. Much of the activity related to
this features will be to our south and east though, leaving clear
skies and slightly warmer -near normal- temperatures prevailing
through the day.
Cutter
Medium Range (Tuesday through Saturday)...
Not much in the way of forecast concerns in the extended period as
temperatures are expected to be seasonable during the period with
the next chance of precipitation not until Saturday.
Tuesday, a weak cold front will push through the forecast area.
Although fropa will be dry, the front will drop high temperatures to
around 40 to the mid 40s. A surface ridge of high pressure will move
through the region on Wednesday. This will bring a return to
southwest flow across the forecast area and warm highs a few
degrees. On Thursday another weak and dry cold front will move
through the area. However, a more interesting feature of note is an
upper level trough digging southward along the west coast. In
response to the digging trough, a ridge will develop in the Plains
and Midwest states. On Friday a cut off low develops in the base of
the west coast trough. Meanwhile another upper level trough moving
from the Northern Plains into the Great Lakes region will flatten
the ridge across the forecast area. At the surface a Canadian high
builds into the region keeping temperatures slightly below average
on Friday with highs ranging from the mid 30s to the lower 40s.
Model solutions diverge as to the evolution of the cut off low in
the southwest on Saturday. The GFS is much more progressive bringing
the cut off upper low out into the Southern Plains developing
showers across the forecast area out ahead of it. The ECMWF is
slower with the upper low keeping it over the southwestern CONUS. To
account for the more progressive GFS solution have include slight
chance pops for Saturday.
73
&&
.AVIATION...
There has been no net eastward movement to the VFR stratus deck this
evening as deep cyclonic flow persists ahead of elongated upper
trough axis. Based on RUC 875mb RH progs, have pushed back clearing
all the way until 15Z.
Winds will remain gusty from the north-northwest, peaking at 25 to
30 knots for the next several hours with only the slightest of
diminishing trends through the day with a general 15G25KT character.
Winds will rapidly diminish between 23 and 00Z with sunset and a
building high pressure ridge.
Bookbinder
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
224 AM EST SUN NOV 27 2011
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO MIGRATE OFFSHORE THROUGH THE
REMAINDER OF THE WEEKEND. A STORM SYSTEM WILL SLOWLY APPROACH THE
AREA FROM THE GULF COAST STATES...CREATING UNSETTLED WEATHER
MONDAY THROUGH EARLY TUESDAY. COOLER AND DRIER AIR WILL FIND ITS
WAY INTO THE REGION MID THROUGH LATE WEEK AS HIGH PRESSURE BUILDS
ACROSS THE EASTERN CAROLINAS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 2:30 AM SUNDAY...DEEP...NEARLY CUT-OFF H/5 LONG WAVE TROUGH
PUSHING EAST ACROSS THE DEEP SOUTH WILL DRIVE A FRONTAL SYSTEM
CLOSER TO THE FORECAST AREA AS HIGH PRESSURE CENTERED EAST OF CAPE
HATTERAS MOVES FURTHER OFFSHORE. GUIDANCE SUGGESTS A WARM FRONT
WILL BE ALIGNED ALONG THE COASTAL CAROLINAS BY DAYBREAK SUNDAY.
SOUTHERLY FLOW AND MOISTURE ADVECTION WILL INCREASE AS GRADIENT
TIGHTENS IN ADVANCE OF FRONTAL SYSTEM...KEEPING TEMPERATURES UP
ABOVE NORMAL TODAY AND TONIGHT. LOOKING FOR HIGHS IN THE LOWER TO
MID 70S TODAY...WITH LOWS IN THE MID 50S OVERNIGHT. MOISTURE
INCREASE WILL BE LIMITED TO THE LOWER LEVELS WITH MID LEVELS
REMAINING QUITE DRY. SATELLITE LOOPS AND MODEL SOUNDINGS SHOW
THERE WILL BE ENOUGH UPPER LEVEL MOISTURE FOR AN INCREASE IN
CIRRUS. HOWEVER...MOST NOTICEABLE INCREASE IN CLOUDS WILL BE AT THE
LOWEST LEVELS AS THE NEAR TERM WEARS ON. PRECIP CHANCES LIMITED TO
SLIGHT CHANCE OR LOW CHANCE FOR SHOWERS EARLY MONDAY MORNING DUE
TO LIMITED DEEP MOISTURE AND WEAK FORCING.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 2:30 AM SUNDAY...A DEEP AND FAIRLY COLD/-25C/ 500MB CUTOFF
LOW WILL PROGRESS SLOWLY ACROSS THE GULF STATES ON MONDAY. AHEAD
OF THIS SYSTEM IN THE LOW LEVELS A NARROW BUT STRONG/INTENSE BAND
OF WARM AND MOIST ADVECTION WILL DEVELOP. THE EXACT TIMING THAT
THIS WAA ZONE CROSSES OUR LONGITUDE HAS BEEN UNCERTAIN FOR DAYS
NOW BUT FINALLY APPEARS TO HAVE CONGEALED INTO A WINDOW A FEW
HOURS EITHER SIDE OF 06Z TUESDAY. THE SURFACE AIRMASS WILL REMAIN
QUITE DRY UNTIL THIS RIBBON OF MOISTURE AND FORCING ARRIVES TO
PRECIP CHANCES LOOK PRETTY SLIM. THE NIGHTTIME PASSAGE OF THE RAIN
WILL MEAN THAT INSTABILITY WILL BE AT A MINIMUM. THIS IS FORTUNATE
SINCE MID AND UPPER WIND FIELDS WILL GROW VERY STRONG AND DEEP
CONVECTION WOULD READILY TURN SEVERE. LOW LEVEL WIND FIELDS WILL
ALSO BE QUITE STRONG MEANING MONDAY NIGHT WILL PROBABLY BRING A
LINE OF MODERATE TO OCCASIONALLY HEAVY RAINFALL ACROSS THE REGION.
EMBEDDED IN THIS LINE WILL BE SOME SHALLOW CONVECTIVE ELEMENTS
THAT MAY CONTAIN STRONG BUT MAINLY SUB-SEVERE WIND GUSTS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 2:30 AM SUNDAY...WEAK HIGH BUILDS IN FROM THE WEST WED AND
THUR WHILE AN UPPER LOW MOVES ACROSS AS WELL ON THURS. THIS
FEATURE WILL BE MOISTURE DEPRIVED AND THUS OF LITTLE CONSEQUENCE.
TEMPERATURES A LITTLE BLOW CLIMO THROUGHOUT. MORE WEAK COOL
ADVECTION IN A SPLIT UPPER FLOW REGIME WILL ROUND OUT THE LONG
TERM. TEMPS WILL STAY ON THE COOL SIDE OF CLIMO AND RAIN FREE
CONDITIONS CONTINUE.
&&
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
AS OF 06Z...MODERATE CONFIDENCE FORECAST OVERNIGHT DUE TO CIGS AND
FOG POTENTIAL. WIDESPREAD CLOUDINESS IS LIKELY ALL DAY SUNDAY...BUT
WITH VFR.
NAM BUFR PROFILES ARE STILL ERRONEOUSLY FORECASTING IFR...SO WILL
CONTINUE TO DISREGARD THEM. LATEST HRRR APPEARS TO BE INITIALIZING
QUITE WELL THE CIGS...SO WILL BLEND WITH GFS FORECAST SOUNDINGS AND
OBS FOR THIS TAF PACKAGE.
WIDESPREAD STRATUS/STRATOCU OVERSPREADING MUCH OF THE SOUTHEAST
ATTM...AND EXPECT THIS TO CONTINUE OVERNIGHT AS LIGHT SOUTHERLY FLOW
ADVECTS MOISTURE INTO THE COLUMN. 00Z SOUNDINGS FROM CHS SHOWED A
PRONOUNCED INVERSION AT AROUND 4500 FT...SO EXPECT MOST OF THE
STRATUS TO REMAIN IN THE 4-5 KFT LEVEL OVERNIGHT...WHICH MATCHES
WELL WITH CURRENT OBS. STILL SOME CONCERN FOR FOG IF CIGS DO NOT
FILL IN AS RAPIDLY AS ANTICIPATED...BUT FOG THREAT HAS DECREASED
ENOUGH THAT MENTION OF VSBY RESTRICTIONS HAS BEEN REMOVED. EXPECT
BKN/OVC 4-5 KFT CIGS THROUGH THE OVERNIGHT.
WIDESPREAD STRATUS/STRATOCU WILL PERSIST ALL DAY SUNDAY WITH LOW-VFR
CIGS. WINDS WILL REMAIN SOUTHERLY ON RETURN FLOW...INCREASING TO
AROUND 10 KTS IN THE AFTN. NO SIGNIFICANT CHANGES AFTER NIGHTFALL
SUNDAY EITHER...AS CIGS WILL PERSIST AND WINDS WILL REMAIN ELEVATED
DUE TO TIGHTENING PG AHEAD OF AN APPROACHING STORM SYSTEM.
EXTENDED OUTLOOK...LOW CONFIDENCE IN STRATUS OVERNIGHT SUNDAY.
SHOWERS/TEMPO MVFR/IFR LIKELY MONDAY AND TUESDAY. VFR WEDNESDAY AND
THURSDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 2:30 AM SUNDAY...SELY WINDS WILL GRADUALLY INCREASE IN
ADVANCE OF A FRONTAL SYSTEM TODAY AND TONIGHT...WITH 15 TO 20 KTS
DEVELOPING BY DAYBREAK MONDAY. SEAS WILL SLOWLY BUILD AS A
RESULT...WITH SOME 6 FOOTERS APPEARING BY THE END OF THE NEAR
TERM...ALTHOUGH INITIALLY SEAS IN THE 3 TO 5 FT RANGE WILL BE
MORE COMMON. HAVE HOISTED SMALL CRAFT ADVISORY DUE TO ONSET OF 6
FT SEAS STARTING LATE TONIGHT.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 2:30 AM SUNDAY...SMALL CRAFT ADVISORY WILL BE IN EFFECT ON
MONDAY IN STRONG PREFRONTAL REGIME AHEAD OF VERY DEEP UPPER LOW
AND SURFACE CYCLONE CROSSING THE NRN GULF STATES. THE COLD FRONT
ASSOCIATED WITH THESE SYSTEMS WILL CROSS THE WATERS JUST AFTER
MIDNIGHT MONDAY NIGHT. WIND WILL VEER BUT NOT SO ABRUPTLY AS ONE
MIGHT EXPECTED. RATHER THAN THE USUAL `CLEAN` FROPA CYCLONIC FLOW
WILL LINGER AS THE SURFACE WAVE ROTATES AROUND THE CENTER OF THE
LOW ALOFT...PINWHEELING IT N ACROSS GA AND ERN TN AND THEN
WESTWARD FROM THERE. THIS WILL TRANSLATE INTO AN EROSION OF
FORECAST CONFIDENCE INTO TUESDAY. NOT ONLY IS THIS EVOLUTION A
LITTLE ON THE UNCOMMON SIDE BUT IT WILL ALSO LEAD TO SEVERAL HOURS
OF LIGHTER WINDS (AND THUS DIMINISHING SEAS) FOLLOWED ONCE AGAIN
BY AN INCREASE IN WINDS AS THE COLD SURGE ENSUES. THE COMPLICATION
WILL HAVE TO DO WITH THE EXPIRATION OF ANY HEADLINES...WHICH MAY
NOT BE WARRANTED NOW THROUGH THE SPAN OF THE SHORT TERM PERIOD.
LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 2:30 AM SUNDAY...MUCH LIGHTER WINDS ON TAP FOR THE LONG TERM
AS HIGH PRESSURE SETTLES IN FROM THE WEST. NOT BEING A VERY STRONG
HIGH THERE WILL ONLY BE A MODERATE GRADIENT IN PLACE ON ITS
EASTERN PERIPHERY. THIS HIGH WILL STAY TO OUR WEST ON THURSDAY AS
AN UPPER DISTURBANCE CROSSES THE AREA. THIS COULD YIELD JUST
ENOUGH LOWERING OF PRESSURE WELL OFF THE COAST TO TIGHTEN THE
GRADIENT SLIGHTLY ACROSS THE FORECAST AREA.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 3 AM MONDAY TO 7 AM EST TUESDAY FOR
AMZ250-252-254-256.
&&
$$
SYNOPSIS...REK
NEAR TERM...REK
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...JDW
MARINE...REK/MBB
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
236 AM CST SUN NOV 27 2011
.SHORT TERM...TODAY THROUGH WEDNESDAY
236 AM CST SUN NOV 27 2011
THE MAIN FOCUS OF THE NEAR TERM IS WITH WHEN THE STRATUS WILL
CLEAR ALONG WITH WHETHER SOME SCATTERED FLURRIES WILL LINGER THIS
MORNING BEFORE DRY CONDITIONS TAKE OVER FOR THE REST OF THE WEEK.
AN ELONGATED MID TO UPPER LEVEL TROUGH THAT EXTENDS FROM WESTERN
ONTARIO SOUTH THROUGH MINNESOTA TO TEXAS CONTINUES TO SLOWLY
PROPAGATE EASTWARD THIS MORNING. THE 500-300MB PV ADVECTION IS
JUST STRONG ENOUGH TO PROVIDE SOME LIFT TO PRODUCE SOME SCATTERED
SNOW FLURRIES ACROSS PARTS OF THE REGION. THERMAL PROFILES FROM
THE 27.05Z RUC AND THE LATEST IR SATELLITE TEMPERATURE SCANS SHOW
THAT THE STRATUS DECK IS IN THE -10 TO -12C RANGE...WHICH WOULD BE
CONDUCIVE TO ICE DEVELOPMENT IN THE CLOUD. THUS...SCATTERED
FLURRIES WILL BE POSSIBLE THROUGH LATE MORNING WHEN THE MID LEVEL
TROUGH AND PV ADVECTION MOVES INTO CENTRAL TO EASTERN WISCONSIN.
EVEN THOUGH THE FLURRIES APPEAR THAT THEY SHOULD COME TO AN END
LATER THIS MORNING...THE STRATUS DECK IS ANOTHER STORY.
CURRENTLY THIS DECK EXTENDS WEST THROUGH MINNESOTA INTO THE EASTERN
PARTS OF NORTH AND SOUTH DAKOTA WITH NO BREAKS EVIDENT WITH IT.
THE 27.00Z NAM AND GFS APPEAR TO BE TOO AGGRESSIVE WITH CLEARING
THESE CLOUDS OUT THIS MORNING WHILE THE 27.05Z RUC ALONG WITH PREVIOUS
RUNS SEEM TO HAVE A BETTER GRIP ON REALITY AND KEEPS THE HIGHER RH
VALUES AROUND UNDER THE 850MB INVERSION INTO EVENING. THE BACK
EDGE OF THE STRATUS APPEARS TO BE LOOSELY TIED TO BEING JUST AHEAD
OF THE MAIN SURFACE TO 925MB RIDGE AXIS...WHICH DOES NOT GET INTO
THE REGION UNTIL TONIGHT. THUS...HAVE GONE WITH A MORE PESSIMISTIC
CLOUD FORECAST FOR TODAY WITH AN EVENTUAL CLEARING TONIGHT AS THE
RIDGE MOVES IN.
AFTER THE RIDGE MOVES THROUGH...LOW LEVEL WINDS WILL SWING AROUND
TO THE SOUTHWEST AHEAD OF THE NEXT DISTURBANCE DROPPING OUT OF
SOUTHERN CANADA. MID LEVEL QG FORCING AND LOW LEVEL FRONTOGENESIS
WEAKENS QUITE A BIT AS THE COLD FRONT DROPS DOWN INTO THE REGION.
MOISTURE DOES REACH SATURATION IN THE MID TO HIGH LEVELS MONDAY
NIGHT INTO TUESDAY MORNING BASED ON 27.00Z NAM AND GFS FORECAST
SOUNDINGS AND RH FIELDS...SO THERE SHOULD BE AN INCREASE IN CLOUD
COVER OVER THIS TIME FRAME. THE LOW LEVEL MOISTURE FEED APPEARS TO
BE TAKEN OVER BY THE CUT OFF LOW IN THE OHIO RIVER VALLEY.
THUS...ANY PRECIPITATION OUT OF THIS SYSTEM LOOKS UNLIKELY AS THIS
FRONT PASSES THROUGH. ANOTHER RIDGE OF HIGH PRESSURE WILL MOVE
INTO THE REGION BEHIND THIS FRONT AS THE CUT OFF LOW TO THE EAST
TRACKS THROUGH THE EASTERN GREAT LAKES REGION.
.LONG TERM...WEDNESDAY NIGHT THROUGH SATURDAY NIGHT
236 AM CST SUN NOV 27 2011
FAIRLY QUIET EXTENDED PERIOD WITH TWO SYSTEMS OF NOTE TO KEEP AN
EYE ON. SOME UNCERTAINTY EXISTS WITH A COLD FRONT THAT DROPS DOWN
THROUGH THE REGION ON THURSDAY WITH SOME OF THE PREVIOUS MODELS
SUGGESTING THAT SOME POST-FRONTAL SNOW COULD FORM. THE LATEST
TREND IS TO GO AWAY FROM THIS THOUGH WITH DRIER AIR IN LOW LEVELS
RESTRICTING ANY PRECIPITATION FROM MAKING IT TO THE GROUND. THE
NEXT CHANCES FOR ANY PRECIPITATION WILL BE ON SATURDAY NIGHT AS
ANOTHER COLD FRONT DROPS DOWN INTO THE REGION.
&&
.AVIATION...THROUGH 06Z MONDAY
1135 PM CST SAT NOV 26 2011
MAIN CONCERN IS ON HOW QUICKLY STRATUS DEPARTS THE AREA SUNDAY. AT 05Z
INFRARED SATELLITE IMAGERY SHOWING LARGE STRATUS DECK IN THE WAKE
OF THE COLD FRONT. BACK EDGE WAS OVER THE EASTERN DAKOTAS AND HAS
SHOWN NO EASTWARD MOVEMENT THROUGH THE EVENING HOURS. 27.00Z NAM
MOST ROBUST IN WANTING TO PUSH THE STRATUS OUT ON SUNDAY MORNING. HOWEVER
BASED ON CURRENT SATELLITE TRENDS THIS APPEARS TO BE TOO FAST.
27.02Z RUC BUFKIT SOUNDING HOLDS ONTO THE LOW LEVEL MOISTURE BELOW
THE INVERSION UNTIL AT LEAST 21Z AT KLSE AND KRST. WILL TREND
TOWARDS THE SLOWER SOLUTION...WITH CEILINGS SCATTERING OUT AT 01Z
AT KLSE AND 23Z AT KRST. UNTIL THEN EXPECT CEILINGS IN THE
015-025K FOOT RANGE AT BOTH SITES. PRESSURE GRADIENT REMAINS TIGHT
AND THUS EXPECT SOME GUSTS TO CONTINUE THROUGH 18Z...AFTER WHICH
THE GRADIENT DOES RELAX SOMEWHAT. ONCE CLOUDS SCATTER OUT...EXPECT
LIGHTER WINDS AND VFR CONDITIONS AFTER 01Z MONDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
236 AM CST SUN NOV 27 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1135 PM CST SAT NOV 26 2011
.SHORT TERM...TONIGHT THROUGH TUESDAY
219 PM CST SAT NOV 26 2011
MAIN FORECAST CONCERNS ARE WITH PRECIPITATION TONIGHT AND THEN
TEMPERATURES THROUGH THE REST OF THE SHORT TERM PERIOD.
CURRENTLY AS OF 21Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED RIDGES OVER BOTH THE WEST AND EAST COASTS OF THE U.S. AND
TROUGHING IN-BETWEEN FROM MANITOBA SOUTHWARD THROUGH TEXAS. BULK OF
THE ENERGY ASSOCIATED WITH THE UPPER TROUGHING HAS BEEN DROPPING
SOUTH INTO TEXAS PER PRESSURE VALUES ON THE 1.5 PV SURFACE. STILL...
GRADUAL HEIGHT FALLS ON THE EAST SIDE OF THE UPPER TROUGH AND
SHORTWAVES MOVING THROUGH THE SOUTHWEST FLOW...COMBINED WITH LOW
LEVEL MOISTURE TRANSPORT...HELPED BRING THE LIGHT TO MODERATE RAIN
TO MUCH OF THE FORECAST AREA THIS MORNING. THIS PRECIPITATION IS
NOW ONLY AFFECTING THE FAR SOUTHEASTERN PORTION OF THE FORECAST
AREA DUE TO A DRY SLOT IN THE MID TO UPPER LEVELS PUNCHING IN
ELSEWHERE. MEANWHILE...VERY WEAK COLD CONVEYOR BELT AROUND A
1006MB SURFACE LOW IN NORTHEAST WISCONSIN IS REFLECTED BY LIGHT
RADAR RETURNS ACROSS CENTRAL MN INTO NORTHWEST WI. A MIX OF LIGHT
RAIN AND SNOW HAS BEEN REPORTED WITH THESE RADAR RETURNS...THANKS
TO SURFACE TEMPERATURES THAT HAVE BEEN FALLING ON GUSTY NORTHWEST
WINDS. OFF TO THE WEST... EVEN COLDER AIR WAS EVIDENT OVER THE
DAKOTAS INTO MONTANA WHERE 12Z 850MB TEMPS WERE OBSERVED AT -5 TO
-7C. COMPARE THIS TO OBSERVED 4-6C OVER THE AREA AT 12Z TODAY.
SKIES DO CLEAR OUT OVER THE WESTERN DAKOTAS...THOUGH...THANKS TO A
DRY 12Z GLASGOW MT SOUNDING.
TONIGHT AND SUNDAY...UPPER TROUGH OVER THE PLAINS IS FORECAST TO
GRADUALLY TRACK EAST DURING THIS PERIOD...WITH THE 500MB AXIS
SITUATED OVER LA CROSSE AT 12Z SUNDAY AND THEN OVER EASTERN
WISCONSIN AT 00Z MONDAY. SINCE THIS UPPER TROUGH IS COMING THROUGH
POSITIVELY TILTED AND AGAIN MOST OF THE ENERGY DROPPING SOUTH INTO
THE SOUTHERN PLAINS...VERY LITTLE IN THE WAY OF FORCING IS EXPECTED.
MAIN PRECIPITATION LOOKS TO BE THE CURRENT WEAK COLD CONVEYOR BELT
OVER CENTRAL MINNESOTA WHICH SHOULD SLIDE THROUGH MUCH OF THE
FORECAST AREA THIS EVENING. CANNOT RULE OUT A FEW HUNDREDTHS OF
QPF...AS INDICATED BY THE 26.12Z NAM/26.00Z ECMWF...BUT THE
PROBABILITY SEEMS TOO LOW TO GO MORE THAN A 50 PERCENT CHANCE GIVEN
NEARLY DRY 26.09Z SREF MEAN/26.12Z GFS AND GIVEN WEAK APPEARANCE OF
CONVEYOR BELT ON RADAR. PRECIPITATION TYPE WILL BE DETERMINED BY THE
SURFACE TEMPERATURE GIVEN THE WARMEST LAYER AT THE SURFACE...MAKING
IT A RAIN/SNOW SCENARIO. HOWEVER...THERE ARE SOME HINTS OF LOSS OF
ICE DUE TO SOME DRIER AIR IN THE 10000-15000 FT LAYER...WHICH COULD
ALLOW FOR JUST A LITTLE MORE LIQUID VS SNOW. NOT ENOUGH CONFIDENCE
EXISTS TO MENTION ANY FREEZING PRECIPITATION...THOUGH...DUE TO
QUESTION MARKS ON AMOUNT OF PRECIPITATION IN GENERAL AND SURFACE
TEMPERATURES LIKELY TAKING AWHILE TO FALL BELOW FREEZING. ANY
SNOW ACCUMULATION LIKELY TO BE VERY LIGHT IF AT ALL TOO. OVERNIGHT
HOURS THROUGH SUNDAY LOOK MOSTLY DRY AS THE UPPER TROUGH PUSHES
EAST AND SUBSIDENCE COMES IN. CERTAINLY MUCH COOLER WEATHER DURING
THIS PERIOD AS 850MB TEMPS TANK TO -4 TO -8C BY 12Z SUNDAY...ALONG
WITH THE BLUSTERY NORTHWEST WINDS. NOT A WHOLE LOT OF MODIFICATION
EXPECTED TOMORROW WITH CLEARING NOT COMING IN UNTIL LATE AND 850MB
TEMPS STAYING BELOW -2C. IN FACT...ANY CLEARING MAY ONLY OCCUR IN
THE FAR WESTERN FORECAST AREA.
SUNDAY NIGHT THROUGH TUESDAY...QUIET WEATHER LOOKS TO DOMINATE THE
FORECAST AREA DESPITE A FRONTAL PASSAGE LIKELY TO MOVE THROUGH VERY
LATE MONDAY. THINGS WILL BE MORE ACTIVE TO OUR SOUTHEAST AS AN UPPER
LOW FORMS OVER THE SOUTHEASTERN U.S....BUT ANY PRECIPITATION
WRAPPING BACK AROUND THIS UPPER LOW LOOKS TO STAY EAST AND SOUTH OF
CHICAGO. REGARDING THE FRONTAL PASSAGE...A NORTHERN STREAM UPPER
LEVEL TROUGH CURRENTLY OVER THE EASTERN PACIFIC IS FORECAST TO CROSS
THE DAKOTAS ON MONDAY...BRINGING A SURGE OF DOWNSLOPED WARMED AIR
INTO THE FORECAST AREA. 850MB TEMPS ACTUALLY CLIMB UP TO 4-6C BY 00Z
TUESDAY. PROBLEM IS THAT A LOT OF THE WARMING TAKES PLACE ALOFT AND
WE WILL NOT BE ABLE TO MIX UP TO IT...DUE TO THE LOW SUN ANGLE AND
LIGHT WINDS FORECAST. STILL...MIXING UP TO 925MB IS LIKELY WITH FULL
SUNSHINE RESULTING IN HIGHS IN THE UPPER 30S TO LOW 40S. THIS SHOULD
BE A NICE REBOUND AFTER SUNDAY NIGHT LOWS LIKELY IN THE MID TEENS TO
MID 20S...COLDEST IN THE TYPICAL COLD SPOTS. DRY WEATHER EXPECTED
WITH THE FRONTAL PASSAGE DUE TO LACK OF MOISTURE...THEN COOLER
TEMPERATURES COME IN AGAIN AS HIGH PRESSURE BUILDS BACK OVER THE
PLAINS FOR MONDAY NIGHT AND TUESDAY. 850MB TEMPS THIS TIME DO NOT
FALL AS MUCH...ONLY TO -2 TO -4C...SO TUESDAY SHOULD END UP A LITTLE
WARMER THAN SUNDAY. MAY HAVE SOME THICKER HIGH CLOUDS TO DEAL WITH
IN THE MORNING COMING OFF THE SOUTHEASTERN UPPER LOW TO LIMIT
FIXING...BUT THESE LOOK TO START CLEARING OUT IN THE AFTERNOON.
.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY
219 PM CST SAT NOV 26 2011
SIMILAR TO THE SUNDAY NIGHT THROUGH TUESDAY TIME PERIOD...MUCH OF
THE EXTENDED LOOKS QUIET...THOUGH PLENTY OF UNCERTAINTY EXISTS WITH
THE UPPER LEVEL PATTERN HEADING INTO NEXT WEEKEND. LONGWAVE PATTERN
FEATURES UPPER RIDGING BUILDING INTO THE AREA ON WEDNESDAY BETWEEN
THE UPPER LOW LIFTING UP THE EAST COAST AND TROUGHING DIGGING DOWN
THE WEST COAST. SHOULD SEE WARMER TEMPERATURES ON WEDNESDAY
ASSOCIATED WITH THE UPPER RIDGING...THOUGH NOT MUCH ABOVE NORMAL
GIVEN 850MB TEMPS ONLY 2-4C. THIS TROUGHING LOOKS TO SPLIT INTO
TWO...WITH THE NORTHERN STREAM PORTION CROSSING THE FORECAST AREA
THURSDAY NIGHT. MODELS HAVE BEEN SPLIT WHETHER OR NOT FRONTOGENESIS
AND DPVA FORCING AHEAD OF THE NORTHERN STREAM TROUGH CAN PRODUCE
LIGHT SNOW...MOSTLY DUE TO LACK OF MOISTURE WITH IT. CONSENSUS OF
GUIDANCE SUGGESTS JUST A 10-15 PERCENT CHANCE FOR BOTH THURSDAY AND
THURSDAY NIGHT...WHICH RESULTS IN A DRY FORECAST. MORE IMPORTANTLY
IS THE 850MB TEMPS ACCOMPANYING THE TROUGH. MODELS HAVE BEEN
INCONSISTENT INCLUDING RUN TO RUN ON HOW COLD THE AIR IS WITH IT.
CURRENT CONSENSUS IS BETWEEN -8 TO -12C...BUT HAVE SEEN MODELS BOTH
WARMER AND COLDER. THIS SHOULD SET UP TEMPERATURES BELOW NORMAL FOR
FRIDAY AS AN AREA OF HIGH PRESSURE BUILDS IN. HEADING INTO THE
WEEKEND...MODELS ARE IN AGREEMENT OF RIDGING BUILDING UP IN THE
EASTERN PACIFIC. QUESTION IS WHERE SHORTWAVES DIG DOWN TO ON THE
EAST SIDE OF THIS RIDGE. THE 26.12Z GFS AND SOME GFS ENSEMBLE
MEMBERS ALLOW SHORTWAVES TO DIG DOWN INTO THE WESTERN U.S....
RESULTING IN DOWNSTREAM RIDGING OVER THE FORECAST AREA. OTHERS LIKE
THE 26.00Z/26.12Z ECMWF AND OTHER GFS ENSEMBLE MEMBERS DIG THE
SHORTWAVES DOWN MORE OVER THE NORTHERN PLAINS INTO OUR REGION BY
MAINTAINING NORTHWEST FLOW. FOLLOWED A SOMEWHAT OF CONSENSUS
APPROACH WHICH JUST PLACES SOME 10-20 PERCENT CHANCES OVER THE AREA
ON SATURDAY...MAINLY NORTH OF I-90 WITH A SHORTWAVE TROUGH GOING
THROUGH THERE. SLIGHTLY WARMER TEMPERATURES WOULD OCCUR ON SATURDAY
AS WELL WITH WARM ADVECTION ASSOCIATED WITH THE SHORTWAVE TROUGH.
IN SUMMARY...EXTENDED LOOKS AROUND NORMAL ON TEMPERATURES WITH
MAINLY DRY CONDITIONS.
&&
.AVIATION...THROUGH 06Z MONDAY
1135 PM CST SAT NOV 26 2011
MAIN CONCERN IS ON HOW QUICKLY STRATUS DEPARTS THE AREA SUNDAY. AT 05Z
INFRARED SATELLITE IMAGERY SHOWING LARGE STRATUS DECK IN THE WAKE
OF THE COLD FRONT. BACK EDGE WAS OVER THE EASTERN DAKOTAS AND HAS
SHOWN NO EASTWARD MOVEMENT THROUGH THE EVENING HOURS. 27.00Z NAM
MOST ROBUST IN WANTING TO PUSH THE STRATUS OUT ON SUNDAY MORNING. HOWEVER
BASED ON CURRENT SATELLITE TRENDS THIS APPEARS TO BE TOO FAST.
27.02Z RUC BUFKIT SOUNDING HOLDS ONTO THE LOW LEVEL MOISTURE BELOW
THE INVERSION UNTIL AT LEAST 21Z AT KLSE AND KRST. WILL TREND
TOWARDS THE SLOWER SOLUTION...WITH CEILINGS SCATTERING OUT AT 01Z
AT KLSE AND 23Z AT KRST. UNTIL THEN EXPECT CEILINGS IN THE
015-025K FOOT RANGE AT BOTH SITES. PRESSURE GRADIENT REMAINS TIGHT
AND THUS EXPECT SOME GUSTS TO CONTINUE THROUGH 18Z...AFTER WHICH
THE GRADIENT DOES RELAX SOMEWHAT. ONCE CLOUDS SCATTER OUT...EXPECT
LIGHTER WINDS AND VFR CONDITIONS AFTER 01Z MONDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
219 PM CST SAT NOV 26 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS GOODLAND KS
530 AM MST SUN NOV 27 2011
.SHORT TERM (TODAY-TUESDAY)...
220 AM MST SUN NOV 27 2011
EARLY MORNING WV IMAGERY AND RUC H5 ANALYSIS SHOW UPPER LEVEL
PATTERN DOMINATED BY HIGHLY AMPLIFIED RIDGE-TROUGH PATTERN. H5
RIDGE CURRENTLY CENTERED OFF SOUTHERN CALIFORNIA COAST...WITH AXIS
EXTENDING NORTH TO SASKATCHEWAN CANADA. TROUGH AXIS CURRENTLY
EXTENDS FROM WESTERN GREAT LAKES REGION TO SOUTHERN TEXAS. BETWEEN
THESE FEATURES NORTHERLY FLOW AND LARGE SCALE SUBSIDENCE IS IN
PLACES ACROSS PLAINS.
H5 RIDGE WILL DOMINATE PATTERN OVER CWA THROUGH MON...WITH MILD
TEMPS AND DRY CONDITIONS EXPECTED. SHORTWAVE TROUGH PASSES OVER
CWA MONDAY NIGHT...WITH ASSOCIATED COLD FRONT MOVING THROUGH
DURING 18-00Z TIME PERIOD. SHOULD SEE DECENT WARMING AHEAD OF
FRONTAL PASSAGE WITH HIGHS WARMING TO NEAR 60 OVER MOST OF CWA
MIDDAY MONDAY...AND TO MID 60S ACROSS SOUTHERN EXTENT OF CWA.
WHILE GUIDANCE SHOWS TD VALUES INCREASING AHEAD OF FROPA TO LOW
20S...RH VALUES NEAR 18-20% STILL FORECAST ACROSS SOUTHERN PART OF
CWA. WITH GUSTY WINDS DEVELOPING DURING THE AFTERNOON...COULD SEE
A BRIEF WINDOW OF OVERLAP OF NEAR RED FLAG CONDITIONS BEFORE RH
VALUES INCREASE. LOOKS MARGINAL...SO NOT PLANNING ANY HIGHLIGHTS
THIS FORECAST CYCLE.
COULDNT RULE OUT A FEW SPRINKLES/FLURRIES DURING A BRIEF WINDOW
MONDAY NIGHT. HOWEVER...DUE TO THE PROGRESSIVE NATURE OF THIS WAVE
SUBSIDENCE WILL BE QUICK TO BUILD BACK OVER CWA...AND LARGE SCALE
ASCENT IS SOUTHEAST OF CWA BY TIME GUIDANCE SHOWS MID LEVELS
SATURATING. WILL KEEP MENTION OUT OF FORECAST FOR NOW.
SHORTWAVE RIDGING QUICKLY BUILDS BACK OVER CWA BEHIND DEPARTING
TROUGH...WITH DRY CONDITIONS AND SEASONAL TEMPS IN THE MID-UPPER
40S ON TUESDAY.
DR
.LONG TERM (WEDNESDAY-SATURDAY)...
220 AM MST SUN NOV 27 2011
THE UPPER LEVEL RIDGE WILL REMAIN OVER THE CWA WEDNESDAY BEFORE THE
UPPER LEVEL FLOW TRANSITIONS TO MORE OF A SPLIT FLOW PATTERN
THURSDAY THROUGH SATURDAY...WITH A CLOSED LOW OVER THE WESTERN CONUS
AND AN UPPER LEVEL TROUGH OVER THE NORTH AND NORTHEAST CONUS.
MODELS ARE COMING INTO BETTER AGREEMENT WITH THE SPLIT FLOW PATTERN
AND THE FRONTAL TIMING FOR THURSDAY. CURRENTLY THE STRONG COLD
FRONT LOOKS TO MOVE THROUGH DURING THE OVERNIGHT OR EARLY MORNING
HOURS. MODELS CONTINUE TO SHOW PRECIP. AND WINDY CONDITIONS BEHIND
THE FRONT THURSDAY. HOWEVER MOST OF THE PRECIP. AND FORCING IS
DEPICTED WEST OF THE CWA.
FROM FRIDAY THROUGH THE WEEKEND THE MODELS ARE MUCH LESS
CONFIDENT WITH THE UPPER LEVEL FLOW. GENERALLY THE CLOSED LOW OVER
THE SOUTHWEST CONUS MERGES WITH AN UPPER LEVEL TROUGH THAT MOVES
DOWN FROM CANADA DURING THE WEEKEND. THE PLACEMENT OF THE UPPER
LEVEL FEATURES ONCE THE CLOSED LOW IS ABSORBED INTO THE MAIN FLOW IS
STILL IN QUESTION. GENERALLY THE CLOSED LOW WILL MERGE WITH THE
MAIN FLOW OVER THE WESTERN HIGH PLAINS...PLACING AN UPPER LEVEL
TROUGH OVER THE CENTRAL CONUS. AHEAD OF THE UPPER LEVEL TROUGH
ANOTHER COLD FRONT WILL MOVE THROUGH THE CWA. NOT TOO CONFIDENT
WITH PRECIP. CHANCES BEHIND THE FRONT AS THIS WILL DEPEND ON
WHETHER THE UPPER LEVEL FLOW WILL MERGE BEFORE MOVING OVER THE CWA
SENDING MOISTURE OUR WAY...OR REMAIN SPLIT WHICH WOULD SEND THE
MOISTURE TO OUR NORTH AND SOUTH.
TEMPERATURES THROUGH THE PERIOD WILL BE WARMEST ON WEDNESDAY BEFORE
THE COLD FRONT MOVES THROUGH. THROUGH THE REST OF THE WEEK
TEMPERATURES WILL BE ROUGHLY 10 DEGREES BELOW NORMAL AS THE COLD AIR
REMAINS OVER THE CWA. A BRIEF WARM UP WILL OCCUR SATURDAY...WITH
NEAR NORMAL TEMPERATURES BEFORE THE NEXT COLD FRONT MOVES
THROUGH.
JTL
&&
.AVIATION...
528 AM MST SUN NOV 27 2011
VFR CONDITIONS WILL PREVAIL FOR THE 12Z TAFS. UPPER LEVEL RIDGE
WILL CONTINUE TO BUILD OVER THE AREA TODAY. LIGHT NORTH TO NORTH
NORTHWEST WINDS CAN BE EXPECTED AND SKIES WILL BE CLEAR.
JTL
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1022 AM EST SUN NOV 27 2011
.UPDATE...
IT HAS BEEN A STRUGGLE TO SEE LES DEVELOPMENT THIS MORNING...MOST
LIKELY DUE TO THE VERY STRONG SUBSIDENCE INVERSION NOTED ON THE 12Z
INL SOUNDING AND NEUTRAL TO JUST SLIGHTLY CYCLONIC PBL FLOW. HAVE
SEEN SOME BETTER BANDING BETWEEN MARQUETTE AND MUNISING IN THE LAST
FEW HOURS MOST LIKELY OWED TO SLIGHT ENHANCEMENT FROM LAKE NIPIGON
AND FROM BEING ON THE WESTERN EDGE OF THE MID LEVEL CLOUDS. WITH
THAT BEING SAID...HAVE RAISED POPS THIS MORNING IN WESTERN ALGER
COUNTY TO CATEGORICAL AND ALSO RAISED ACCUMULATIONS TO UP TO 3
INCHES WELL INLAND OF LAKE SUPERIOR. IF NOTHING ELSE...SOME
UNTREATED ROADS WILL BECOME A LITTLE SLIPPERY IN THIS AREA ALONG THE
M-94 CORRIDOR BETWEEN SKANDIA AND WETMORE.
OTHERWISE...WITH THE DRY AIR AND BUILDING HEIGHTS MOVING INTO
WESTERN UPPER MI BY THIS AFTN...HAVE OPTED TO JUST GO WITH SCATTERED
SNOW SHOWERS FOR THE REMAINDER OF THE DAY IN THIS AREA.
IN ADDITION...TEMPS WILL STRUGGLE TO RISE MUCH TODAY DUE TO CLOUD
COVER AND COLD ADVECTION. WILL GENERALLY GO WITH STEADY TEMPS IN THE
UPPER 20S WEST AND MID 30S EAST.
&&
PREV DISCUSSION...ISSUED AT 625 AM EST SUN NOV 27 2011...
.SYNOPSIS /ISSUED AT 442 AM/...
WV IMAGERY AND RUC ANALYSIS INDICATED A HIGH AMPLITUDE PATTERN WITH
A MID/UPPER LEVEL RIDGE OVER THE WRN CONUS AND A TROUGH OVER THE
CNTRL CONUS FROM NW ONTARIO TO CNTRL TX. THE BACK EDGE OF THE DEEPER
MOISTURE WAS MOVING STEADILY EASTWARD AND WAS NEAR A INL-MSP LINE.
AT THE SFC...LOW PRES NE OF LAKE SUPERIOR CONTINUED TO LIFT OFF TO
THE NE THROUGH NRN ONTARIO. CAA IN THE WAKE OF THE LOW HAD DROPPED
850 MB TEMPS TO NEAR -10C OVER WRN LAKE SUPERIOR. EVEN THOUGH
KINL/CYPL SOUNDINGS INDICATED A MOISTURE PROFILE THROUGH LOW AND MID
LEVELS FAVORABLE FOR LAKE EFFECT SNOW...WITH ONLY MARGINAL
INSTABILITY (LK-H8 DELTA/T TO 15C)AND THE CLOUD LAYER BLO THE DGZ
LAYER (10K-14K FT) SNOW HAS BEEN RELATIVELY LIGHT. BRIEF PERIODS OF
LAKE ENHANCED SNOW AT IWD AND AT NWS MQT HAVE RESULTED IN A LIGHT
COATING OF SNOW. IR LOOP SHOWED THE BACK EDGE OF THE LOW CLOUDS TO
NEAR THE MN/DAKOTAS BORDER.
&&
.DISCUSSION...
TODAY AND TONIGHT...EXPECT SCT/NMRS LIGHT LAKE EFFECT SNOW SHOWERS
TO CONTINUE FOR LOCATIONS FAVORED BY NNW FLOW. THE RELATIVELY SHORT
FETCH LENGTH INTO THE WEST WILL LIMIT ACCUMULATION POTENTIAL. THE
LOCAL HIGH RES WRF/ARW SUGGESTS THAT UPSTREAM CONDITIONING FROM LAKE
NIPIGON AND SLIGHTLY MORE N THAN NNW FLOW MAY SUPPORT LES BANDS INTO
NORTH CENTRAL UPPER MI. THE LATER ARRIVAL OF THE COLD AIR INTO THE
EAST TIL THE AFTER THE MOISTURE DEPARTS WILL ALSO BE UNFAVORABLE FOR
ANY SIGNIFICANT ACCUMULATIONS. THE LES SHOULD DIMINISH DURING THE
AFTERNOON AS 800-700 MB DRYING MOVE IN. OVERALL...GIVEN THE LACK OF
SYNOPTIC SCALE UPWARD MOTION WITH THE MARGINAL INSTABILITY...ONLY
MINOR ACCUMULATIONS OF AN INCH OR LESS ARE EXPECTED.
TONIGHT...ANY REMAINING LES WILL GRADUALLY END AS SFC AND MID LEVEL
RIDGING BUILD INTO THE THE REGION WITH ACYC FLOW AND INVERSION
HEIGHTS FALLING TO AROUND 3K FT. WITH FAVORABLE RADIATIONAL COOLING
CONDITIONS INLAND OVERNIGHT...MIN TEMPS WILL FALL INTO THE MID TEENS
WHILE LAKE CLOUDS KEEP TEMPS INT THE MID 20S EAST.
MONDAY INTO TUE...MDLS WERE IN REASONABLE AGREEMENT WITH A NRN
STREAM SHORTWAVE TROUGH MOVING INTO MANITOBA MON AND THROUGH NRN
ONTARIO EARLY TUE WHICH WILL DRAG A COLD FRONT THROUGH LAKE
SUPERIOR. WITH LITTLE MOISTURE AVAILABLE ONLY WEAK DYNAMICS ON
THE SRN TAIL OF THE SHRTWV...NO MEASURABLE PCPN IS EXPECTED. WITH SW
LOW LEVEL WAA AND SUNSHINE AHEAD OF THE TROUGH ON MON...TEMPS WILL
REBOUND INTO THE UPPER 30S TO AROUND 40. WITH ONLY MODERATE CAA
BEHIND THE FRONT AND A RELATIVELY DRY AIRMASS 850 MB TEMPS TO AROUND
-6C WILL NOT BE LOW ENOUGH TO PRODUCE LES. PCPN ASSOCIATED WITH THE
CUTOFF LOW ALSO WILL REMAIN EAST OF THE AREA TUE AS DRY NRLY FLOW
(PWAT DOWN TO NEAR 0.10 INCH) DOMINATES THE AREA.
WED THROUGH SAT...THE GFS/ECMWF/GEM WERE CONSISTENT IN SHOWING TREND
TOWARD TROUGHING INTO THE CNTRL CONUS AS A RIDGE BUILDS OVER THE ERN
PACIFIC. WITH THIS PATTERN...COLDER WILL MOVE INTO THE GREAT LAKES
WITH POTENTIAL FOR SOME LES. TIMING IS UNCERTAIN...BUT GFS/ECMWF
CONSENSUS SUGGESTS THAT A SHORTWAVE WILL MOVE THROUGH THU WITH 850 MB
TEMPS FALLING TO NEAR -13C BY LATE THU INTO THU NIGHT. EVEN THOUGH
THIS SHOULD PROVIDE ENOUGH INSTABILITY FOR LES...FCST DRY 850-700 MB
MOISTURE WILL BE UNFAVORABLE FOR SIGNIFICANT ACCUMULATIONS. A
PROGRESSIVE NRN STREAM FLOW WOULD LEAD TO WAA FRI INTO SAT WITH
RECOVERING TEMPS AND MAINLY DRY WEATHER.
&&
.AVIATION /FOR THE 12Z TAF ISSUANCE/...
EXPECT MVFR CIGS TO PREDOMINATE THRU THE DAY ALONG WITH SOME -SHSN
AS GUSTY NW WINDS BLOW COLDER AIR ACROSS THE RELATIVELY WARM WATERS
OF LK SUP AND MAINTAIN MOIST LYR UNDER LLVL INVERSION. THE APRCH OF
HI PRES TNGT AND MUCH DRIER LLVL AIR WILL ALLOW AN IMPROVEMENT TO
VFR CONDITIONS AND CAUSE THE GUSTY WINDS TO DIMINISH.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
EXPECT N TO NW WINDS UP TO 30 KTS WITH A FEW GALE FORCE GUSTS TO 35
KTS TO DIMINISH THIS AFTERNOON WITH THE APPROACH OF HI PRES FROM
MINNESOTA. LIGHT WINDS TONIGHT WITH THE PASSAGE OF THE HI WILL GIVE
WAY TO A STRONGER SW FLOW ON MON AS THE PRES GRADIENT SHARPENS
BETWEEN THE HI DRIFTING INTO THE LOWER LAKES AND ANOTHER APPROACHING
COLD FRONT. LOOK FOR A WSHFT TO THE N BEHIND THIS FRONT ON MON NIGHT
AND STRENGTHENING WINDS MAINLY OVER THE E HALF INTO TUE ON THE NW
FLANK OF A DEEP LO PRES MOVING THRU THE LOWER GREAT LAKES INTO
ONTARIO. DEPENDING ON HOW FAR W THIS LO DRIFTS...N GALES TO 35 KTS
ARE POSSIBLE OVER PORTIONS OF THE E HALF. THE STRONGER WINDS WILL
DIMINISH TUE NIGHT THRU WED WITH THE APPROACH OF ANOTHER HI PRES
SYSTEM...BUT A STRONGER NW FLOW WILL DEVELOP ON THU IN THE WAKE OF
ANOTHER COLD FROPA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MRD
SYNOPSIS...JLB
DISCUSSION...JLB
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
625 AM EST SUN NOV 27 2011
UPDATED AVIATION DISCUSSION FOR 12Z TAFS
.SYNOPSIS /ISSUED AT 442 AM/...
WV IMAGERY AND RUC ANALYSIS INDICATED A HIGH AMPLITUDE PATTERN WITH
A MID/UPPER LEVEL RIDGE OVER THE WRN CONUS AND A TROUGH OVER THE
CNTRL CONUS FROM NW ONTARIO TO CNTRL TX. THE BACK EDGE OF THE DEEPER
MOISTURE WAS MOVING STEADILY EASTWARD AND WAS NEAR A INL-MSP LINE.
AT THE SFC...LOW PRES NE OF LAKE SUPERIOR CONTINUED TO LIFT OFF TO
THE NE THROUGH NRN ONTARIO. CAA IN THE WAKE OF THE LOW HAD DROPPED
850 MB TEMPS TO NEAR -10C OVER WRN LAKE SUPERIOR. EVEN THOUGH
KINL/CYPL SOUNDINGS INDICATED A MOISTURE PROFILE THROUGH LOW AND MID
LEVELS FAVORABLE FOR LAKE EFFECT SNOW...WITH ONLY MARGINAL
INSTABILITY (LK-H8 DELTA/T TO 15C)AND THE CLOUD LAYER BLO THE DGZ
LAYER (10K-14K FT) SNOW HAS BEEN RELATIVELY LIGHT. BRIEF PERIODS OF
LAKE ENHANCED SNOW AT IWD AND AT NWS MQT HAVE RESULTED IN A LIGHT
COATING OF SNOW. IR LOOP SHOWED THE BACK EDGE OF THE LOW CLOUDS TO
NEAR THE MN/DAKOTAS BORDER.
&&
.DISCUSSION...
TODAY AND TONIGHT...EXPECT SCT/NMRS LIGHT LAKE EFFECT SNOW SHOWERS
TO CONTINUE FOR LOCATIONS FAVORED BY NNW FLOW. THE RELATIVELY SHORT
FETCH LENGTH INTO THE WEST WILL LIMIT ACCUMULATION POTENTIAL. THE
LOCAL HIGH RES WRF/ARW SUGGESTS THAT UPSTREAM CONDITIONING FROM LAKE
NIPIGON AND SLIGHTLY MORE N THAN NNW FLOW MAY SUPPORT LES BANDS INTO
NORTH CENTRAL UPPER MI. THE LATER ARRIVAL OF THE COLD AIR INTO THE
EAST TIL THE AFTER THE MOISTURE DEPARTS WILL ALSO BE UNFAVORABLE FOR
ANY SIGNIFICANT ACCUMULATIONS. THE LES SHOULD DIMINISH DURING THE
AFTERNOON AS 800-700 MB DRYING MOVE IN. OVERALL...GIVEN THE LACK OF
SYNOPTIC SCALE UPWARD MOTION WITH THE MARGINAL INSTABILITY...ONLY
MINOR ACCUMULATIONS OF AN INCH OR LESS ARE EXPECTED.
TONIGHT...ANY REMAINING LES WILL GRADUALLY END AS SFC AND MID LEVEL
RIDGING BUILD INTO THE THE REGION WITH ACYC FLOW AND INVERSION
HEIGHTS FALLING TO AROUND 3K FT. WITH FAVORABLE RADIATIONAL COOLING
CONDITIONS INLAND OVERNIGHT...MIN TEMPS WILL FALL INTO THE MID TEENS
WHILE LAKE CLOUDS KEEP TEMPS INT THE MID 20S EAST.
MONDAY INTO TUE...MDLS WERE IN REASONABLE AGREEMENT WITH A NRN
STREAM SHORTWAVE TROUGH MOVING INTO MANITOBA MON AND THROUGH NRN
ONTARIO EARLY TUE WHICH WILL DRAG A COLD FRONT THROUGH LAKE
SUPERIOR. WITH LITTLE MOISTURE AVAILABLE ONLY WEAK DYNAMICS ON
THE SRN TAIL OF THE SHRTWV...NO MEASURABLE PCPN IS EXPECTED. WITH SW
LOW LEVEL WAA AND SUNSHINE AHEAD OF THE TROUGH ON MON...TEMPS WILL
REBOUND INTO THE UPPER 30S TO AROUND 40. WITH ONLY MODERATE CAA
BEHIND THE FRONT AND A RELATIVELY DRY AIRMASS 850 MB TEMPS TO AROUND
-6C WILL NOT BE LOW ENOUGH TO PRODUCE LES. PCPN ASSOCIATED WITH THE
CUTOFF LOW ALSO WILL REMAIN EAST OF THE AREA TUE AS DRY NRLY FLOW
(PWAT DOWN TO NEAR 0.10 INCH) DOMINATES THE AREA.
WED THROUGH SAT...THE GFS/ECMWF/GEM WERE CONSISTENT IN SHOWING TREND
TOWARD TROUGHING INTO THE CNTRL CONUS AS A RIDGE BUILDS OVER THE ERN
PACIFIC. WITH THIS PATTERN...COLDER WILL MOVE INTO THE GREAT LAKES
WITH POTENTIAL FOR SOME LES. TIMING IS UNCERTAIN...BUT GFS/ECMWF
CONSENSUS SUGGESTS THAT A SHORTWAVE WILL MOVE THROUGH THU WITH 850 MB
TEMPS FALLING TO NEAR -13C BY LATE THU INTO THU NIGHT. EVEN THOUGH
THIS SHOULD PROVIDE ENOUGH INSTABILITY FOR LES...FCST DRY 850-700 MB
MOISTURE WILL BE UNFAVORABLE FOR SIGNIFICANT ACCUMULATIONS. A
PROGRESSIVE NRN STREAM FLOW WOULD LEAD TO WAA FRI INTO SAT WITH
RECOVERING TEMPS AND MAINLY DRY WEATHER.
&&
.AVIATION /FOR THE 12Z TAF ISSUANCE/...
EXPECT MVFR CIGS TO PREDOMINATE THRU THE DAY ALONG WITH SOME -SHSN
AS GUSTY NW WINDS BLOW COLDER AIR ACROSS THE RELATIVELY WARM WATERS
OF LK SUP AND MAINTAIN MOIST LYR UNDER LLVL INVERSION. THE APRCH OF
HI PRES TNGT AND MUCH DRIER LLVL AIR WILL ALLOW AN IMPROVEMENT TO
VFR CONDITIONS AND CAUSE THE GUSTY WINDS TO DIMINISH.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
EXPECT N TO NW WINDS UP TO 30 KTS WITH A FEW GALE FORCE GUSTS TO 35
KTS TO DIMINISH THIS AFTERNOON WITH THE APPROACH OF HI PRES FROM
MINNESOTA. LIGHT WINDS TONIGHT WITH THE PASSAGE OF THE HI WILL GIVE
WAY TO A STRONGER SW FLOW ON MON AS THE PRES GRADIENT SHARPENS
BETWEEN THE HI DRIFTING INTO THE LOWER LAKES AND ANOTHER APPROACHING
COLD FRONT. LOOK FOR A WSHFT TO THE N BEHIND THIS FRONT ON MON NIGHT
AND STRENGTHENING WINDS MAINLY OVER THE E HALF INTO TUE ON THE NW
FLANK OF A DEEP LO PRES MOVING THRU THE LOWER GREAT LAKES INTO
ONTARIO. DEPENDING ON HOW FAR W THIS LO DRIFTS...N GALES TO 35 KTS
ARE POSSIBLE OVER PORTIONS OF THE E HALF. THE STRONGER WINDS WILL
DIMINISH TUE NIGHT THRU WED WITH THE APPROACH OF ANOTHER HI PRES
SYSTEM...BUT A STRONGER NW FLOW WILL DEVELOP ON THU IN THE WAKE OF
ANOTHER COLD FROPA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
DISCUSSION...JLB
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION ...CORRECTION FOR AVIATION VALID TIME
NWS LA CROSSE WI
552 AM CST SUN NOV 27 2011
.SHORT TERM...TODAY THROUGH WEDNESDAY
236 AM CST SUN NOV 27 2011
THE MAIN FOCUS OF THE NEAR TERM IS WITH WHEN THE STRATUS WILL
CLEAR ALONG WITH WHETHER SOME SCATTERED FLURRIES WILL LINGER THIS
MORNING BEFORE DRY CONDITIONS TAKE OVER FOR THE REST OF THE WEEK.
AN ELONGATED MID TO UPPER LEVEL TROUGH THAT EXTENDS FROM WESTERN
ONTARIO SOUTH THROUGH MINNESOTA TO TEXAS CONTINUES TO SLOWLY
PROPAGATE EASTWARD THIS MORNING. THE 500-300MB PV ADVECTION IS
JUST STRONG ENOUGH TO PROVIDE SOME LIFT TO PRODUCE SOME SCATTERED
SNOW FLURRIES ACROSS PARTS OF THE REGION. THERMAL PROFILES FROM
THE 27.05Z RUC AND THE LATEST IR SATELLITE TEMPERATURE SCANS SHOW
THAT THE STRATUS DECK IS IN THE -10 TO -12C RANGE...WHICH WOULD BE
CONDUCIVE TO ICE DEVELOPMENT IN THE CLOUD. THUS...SCATTERED
FLURRIES WILL BE POSSIBLE THROUGH LATE MORNING WHEN THE MID LEVEL
TROUGH AND PV ADVECTION MOVES INTO CENTRAL TO EASTERN WISCONSIN.
EVEN THOUGH THE FLURRIES APPEAR THAT THEY SHOULD COME TO AN END
LATER THIS MORNING...THE STRATUS DECK IS ANOTHER STORY.
CURRENTLY THIS DECK EXTENDS WEST THROUGH MINNESOTA INTO THE EASTERN
PARTS OF NORTH AND SOUTH DAKOTA WITH NO BREAKS EVIDENT WITH IT.
THE 27.00Z NAM AND GFS APPEAR TO BE TOO AGGRESSIVE WITH CLEARING
THESE CLOUDS OUT THIS MORNING WHILE THE 27.05Z RUC ALONG WITH PREVIOUS
RUNS SEEM TO HAVE A BETTER GRIP ON REALITY AND KEEPS THE HIGHER RH
VALUES AROUND UNDER THE 850MB INVERSION INTO EVENING. THE BACK
EDGE OF THE STRATUS APPEARS TO BE LOOSELY TIED TO BEING JUST AHEAD
OF THE MAIN SURFACE TO 925MB RIDGE AXIS...WHICH DOES NOT GET INTO
THE REGION UNTIL TONIGHT. THUS...HAVE GONE WITH A MORE PESSIMISTIC
CLOUD FORECAST FOR TODAY WITH AN EVENTUAL CLEARING TONIGHT AS THE
RIDGE MOVES IN.
AFTER THE RIDGE MOVES THROUGH...LOW LEVEL WINDS WILL SWING AROUND
TO THE SOUTHWEST AHEAD OF THE NEXT DISTURBANCE DROPPING OUT OF
SOUTHERN CANADA. MID LEVEL QG FORCING AND LOW LEVEL FRONTOGENESIS
WEAKENS QUITE A BIT AS THE COLD FRONT DROPS DOWN INTO THE REGION.
MOISTURE DOES REACH SATURATION IN THE MID TO HIGH LEVELS MONDAY
NIGHT INTO TUESDAY MORNING BASED ON 27.00Z NAM AND GFS FORECAST
SOUNDINGS AND RH FIELDS...SO THERE SHOULD BE AN INCREASE IN CLOUD
COVER OVER THIS TIME FRAME. THE LOW LEVEL MOISTURE FEED APPEARS TO
BE TAKEN OVER BY THE CUT OFF LOW IN THE OHIO RIVER VALLEY.
THUS...ANY PRECIPITATION OUT OF THIS SYSTEM LOOKS UNLIKELY AS THIS
FRONT PASSES THROUGH. ANOTHER RIDGE OF HIGH PRESSURE WILL MOVE
INTO THE REGION BEHIND THIS FRONT AS THE CUT OFF LOW TO THE EAST
TRACKS THROUGH THE EASTERN GREAT LAKES REGION.
.LONG TERM...WEDNESDAY NIGHT THROUGH SATURDAY NIGHT
236 AM CST SUN NOV 27 2011
FAIRLY QUIET EXTENDED PERIOD WITH TWO SYSTEMS OF NOTE TO KEEP AN
EYE ON. SOME UNCERTAINTY EXISTS WITH A COLD FRONT THAT DROPS DOWN
THROUGH THE REGION ON THURSDAY WITH SOME OF THE PREVIOUS MODELS
SUGGESTING THAT SOME POST-FRONTAL SNOW COULD FORM. THE LATEST
TREND IS TO GO AWAY FROM THIS THOUGH WITH DRIER AIR IN LOW LEVELS
RESTRICTING ANY PRECIPITATION FROM MAKING IT TO THE GROUND. THE
NEXT CHANCES FOR ANY PRECIPITATION WILL BE ON SATURDAY NIGHT AS
ANOTHER COLD FRONT DROPS DOWN INTO THE REGION.
&&
.AVIATION...THROUGH 12Z MONDAY
552 AM CST SUN NOV 27 2011
MORNING IR SATELLITE IMAGERY/SURFACE OBSERVATIONS SHOWING WIDESPREAD
MVFR STRATUS ENTRENCHED ACROSS THE UPPER MISSISSIPPI RIVER VALLEY
REGION INCLUDING KRST/KLSE TAF SITES. IN ADDITION...A FAIRLY TIGHT
PRESSURE GRADIENT WAS PRODUCING NORTHWEST WINDS IN THE 15 TO 25 KT
RANGE ACROSS THE AREA. MAIN CONCERN CONTINUES TO BE ON HOW LONG THE
STRATUS LINGERS AS HIGH PRESSURE BUILDS IN FROM THE PLAINS. LATEST
RUC MODELS SOUNDING/BUFKIT SHOWS MOISTURE/STRATUS REMAINING TRAPPED
BELOW THE SUBSIDENCE INVERSION ASSOCIATED WITH THE HIGH THROUGH
TODAY AND INTO THIS EVENING. TRENDED MORE ON THE PESSIMISTIC SIDE...
KEEPING THE BKN-OVC MVFR STRATUS IN AT KRST THROUGH 01Z...THEN
SCATTERING OUT AFTERWARDS AS THE RIDGE AXIS MOVES OVERHEAD. AT
KLSE...THINKING THAT STRATUS SHOULD BREAK UP SOMETIME AROUND 06Z.
WINDS SHOULD SUBSIDE THROUGH THIS AFTERNOON AS THE PRESSURE GRADIENT
RELAXES A BIT...THEN GOING LIGHT LESS THAN 5KT BY 03Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
236 AM CST SUN NOV 27 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS DES MOINES IA
315 PM CST SUN NOV 27 2011
.SHORT TERM /TONIGHT/...
PRIMARY CONCERN REMAINS LOW CLOUD TRENDS. MODELS HAVE HAD A POOR
TIME INITIALIZING AND RESOLVING STRATUS...BUT LATEST RUC SEEMS TO
HAVE THE BEST HANDLE ON THINGS BEING MORE PERSISTENT. THIS
GENERALLY AGREES WITH EXTRAPOLATION NUDGING CLEARING LINE SLOWLY
EASTWARD INTO CENTRAL IA TOWARD MIDNIGHT AND SUGGESTING CLEARING TO
OUR ERN FORECAST AREA BY MORNING BASED ON FURTHER EXTRAPOLATION.
LOW CONFIDENCE IN THESE TRENDS WILL ALSO SPILL OVER INTO MIN TEMPS.
HAVE GENERALLY FOLLOWED GUIDANCE WEST WHERE AIRMASS IS ADEQUATELY
REPRESENTED BY MODELS. HOWEVER NUDGED TEMPS UP ABOVE EVEN THE
WARMEST GUIDANCE EAST WHERE PROLONGED CLOUD COVER IS ANTICIPATED.
CLEARING PROGRESSION WILL MAKE ALL THE DIFFERENCE...SO EXPECT
CONSIDERABLE GRADIENT IN MIN TEMPS.
.LONG TERM /TONIGHT THROUGH SUNDAY/...
FAIRLY BENIGN MID/LONG RANGE WITH LITTLE IN THE WAY OF PRECIPITATION
CHANCES UNTIL THE NEXT WEEKEND. NEXT WEATHER SYSTEM TO IMPACT IOWA
WILL BE A POSITIVELY TILTED SHORTWAVE MOVING ONSHORE IN THE PACIFIC
NORTHWEST AT THIS TIME. THE BRUNT OF THE SHORTWAVE ENERGY
ASSOCIATED WITH THE WAVE WILL PASS TO THE EAST WELL NORTH OF IOWA.
THE SOUTHERN PART OF THE SHORTWAVE SHOULD MERGE WITH LARGE UPPER LOW
OVER THE OHIO VALLEY BY 18Z TUESDAY. THE COLD FRONT ASSOCIATED WITH
THE SHORTWAVE SHOULD CROSS IOWA MONDAY NIGHT. ONLY LIMITED FORCING
AND MOISTURE SHOULD KEEP THE SENSIBLE WEATHER IMPACT LIMITED TO
INCREASED WINDS...CLOUDS AND MODEST COOLING BUT NO PRECIPITATION.
ON MONDAY...THERE SHOULD BE VERY LITTLE BOUNDARY LAYER FLOW WITH THE
CENTER OF A WEAK SURFACE HIGH PRESSURE SYSTEM IN THE AREA. MODEL
SOUNDINGS SHOW A VERY STRONG INVERSION WITH MINIMAL MIXING.
THEREFORE...EXPECT COOL TEMPERATURES WITH LIGHT SURFACE WINDS.
FOR THURSDAY AND BEYOND INTO NEXT WEEKEND...THE GFS AND ECMWF ONCE
AGAIN DIVERGE IN THEIR SOLUTIONS OF THE WEATHER OVER THE UPPER
MIDWEST. THE ECMWF LIFTS OUT AND WEAKENS THE SOUTHWEST UNITED
STATES UPPER LOW INTO THE PLAINS BY NEXT SATURDAY EVENING. THIS
WILL BRING THE NEXT CHANCE OF PRECIPITATION TO IOWA. IT IS FAR TO
EARLY TO DETERMINE THE EXTENT OF THE PRECIPITATION CHANCES OR THE
PRECIPITATION TYPE. FOR NOW...INTRODUCED SMALL POPS SATURDAY NIGHT
INTO SUNDAY.
&&
.AVIATION...27/18Z
PRIMARY CONCERN IN THIS PERIOD WILL BE STRATUS TRENDS. ALTHOUGH THE
RUC IS DOING BETTER...NAM/GFS INITIALIZED THIS LOW LEVEL MOISTURE
POORLY AND WERE TOO AGGRESSIVE ON THE CLEARING. THE STRATUS HAS
MOVED LITTLE THIS MORNING SO HAVE PROLONGED THE SLOW CLEARING UNTIL
THIS EVENING...23Z-07Z WEST-EAST. 17Z SURFACE ANALYSIS PLACES RIDGE
FROM NEBRASKA TO ND/MN BORDER. CLEARING SKIES MAY ALSO LEAD TO FOG
DEVELOPMENT OVERNIGHT AS RIDGE SETTLES IN BEHIND EXITING LOW
CLOUDS. ALTHOUGH LOWER CONDITIONS ARE POSSIBLE...CONFIDENCE IN
THESE TRENDS HAS LEAD TO NO MORE THAN MVFR VSBYS FOR THE TIME BEING.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM/AVIATION...SMALL
LONG TERM...JOHNSON
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1007 AM MST SUN NOV 27 2011
.SHORT TERM (TODAY-TUESDAY)...
220 AM MST SUN NOV 27 2011
EARLY MORNING WV IMAGERY AND RUC H5 ANALYSIS SHOW UPPER LEVEL
PATTERN DOMINATED BY HIGHLY AMPLIFIED RIDGE-TROUGH PATTERN. H5
RIDGE CURRENTLY CENTERED OFF SOUTHERN CALIFORNIA COAST...WITH AXIS
EXTENDING NORTH TO SASKATCHEWAN CANADA. TROUGH AXIS CURRENTLY
EXTENDS FROM WESTERN GREAT LAKES REGION TO SOUTHERN TEXAS. BETWEEN
THESE FEATURES NORTHERLY FLOW AND LARGE SCALE SUBSIDENCE IS IN
PLACES ACROSS PLAINS.
H5 RIDGE WILL DOMINATE PATTERN OVER CWA THROUGH MON...WITH MILD
TEMPS AND DRY CONDITIONS EXPECTED. SHORTWAVE TROUGH PASSES OVER
CWA MONDAY NIGHT...WITH ASSOCIATED COLD FRONT MOVING THROUGH
DURING 18-00Z TIME PERIOD. SHOULD SEE DECENT WARMING AHEAD OF
FRONTAL PASSAGE WITH HIGHS WARMING TO NEAR 60 OVER MOST OF CWA
MIDDAY MONDAY...AND TO MID 60S ACROSS SOUTHERN EXTENT OF CWA.
WHILE GUIDANCE SHOWS TD VALUES INCREASING AHEAD OF FROPA TO LOW
20S...RH VALUES NEAR 18-20% STILL FORECAST ACROSS SOUTHERN PART OF
CWA. WITH GUSTY WINDS DEVELOPING DURING THE AFTERNOON...COULD SEE
A BRIEF WINDOW OF OVERLAP OF NEAR RED FLAG CONDITIONS BEFORE RH
VALUES INCREASE. LOOKS MARGINAL...SO NOT PLANNING ANY HIGHLIGHTS
THIS FORECAST CYCLE.
COULDNT RULE OUT A FEW SPRINKLES/FLURRIES DURING A BRIEF WINDOW
MONDAY NIGHT. HOWEVER...DUE TO THE PROGRESSIVE NATURE OF THIS WAVE
SUBSIDENCE WILL BE QUICK TO BUILD BACK OVER CWA...AND LARGE SCALE
ASCENT IS SOUTHEAST OF CWA BY TIME GUIDANCE SHOWS MID LEVELS
SATURATING. WILL KEEP MENTION OUT OF FORECAST FOR NOW.
SHORTWAVE RIDGING QUICKLY BUILDS BACK OVER CWA BEHIND DEPARTING
TROUGH...WITH DRY CONDITIONS AND SEASONAL TEMPS IN THE MID-UPPER
40S ON TUESDAY.
DR
.LONG TERM (WEDNESDAY-SATURDAY)...
220 AM MST SUN NOV 27 2011
THE UPPER LEVEL RIDGE WILL REMAIN OVER THE CWA WEDNESDAY BEFORE THE
UPPER LEVEL FLOW TRANSITIONS TO MORE OF A SPLIT FLOW PATTERN
THURSDAY THROUGH SATURDAY...WITH A CLOSED LOW OVER THE WESTERN CONUS
AND AN UPPER LEVEL TROUGH OVER THE NORTH AND NORTHEAST CONUS.
MODELS ARE COMING INTO BETTER AGREEMENT WITH THE SPLIT FLOW PATTERN
AND THE FRONTAL TIMING FOR THURSDAY. CURRENTLY THE STRONG COLD
FRONT LOOKS TO MOVE THROUGH DURING THE OVERNIGHT OR EARLY MORNING
HOURS. MODELS CONTINUE TO SHOW PRECIP. AND WINDY CONDITIONS BEHIND
THE FRONT THURSDAY. HOWEVER MOST OF THE PRECIP. AND FORCING IS
DEPICTED WEST OF THE CWA.
FROM FRIDAY THROUGH THE WEEKEND THE MODELS ARE MUCH LESS
CONFIDENT WITH THE UPPER LEVEL FLOW. GENERALLY THE CLOSED LOW OVER
THE SOUTHWEST CONUS MERGES WITH AN UPPER LEVEL TROUGH THAT MOVES
DOWN FROM CANADA DURING THE WEEKEND. THE PLACEMENT OF THE UPPER
LEVEL FEATURES ONCE THE CLOSED LOW IS ABSORBED INTO THE MAIN FLOW IS
STILL IN QUESTION. GENERALLY THE CLOSED LOW WILL MERGE WITH THE
MAIN FLOW OVER THE WESTERN HIGH PLAINS...PLACING AN UPPER LEVEL
TROUGH OVER THE CENTRAL CONUS. AHEAD OF THE UPPER LEVEL TROUGH
ANOTHER COLD FRONT WILL MOVE THROUGH THE CWA. NOT TOO CONFIDENT
WITH PRECIP. CHANCES BEHIND THE FRONT AS THIS WILL DEPEND ON
WHETHER THE UPPER LEVEL FLOW WILL MERGE BEFORE MOVING OVER THE CWA
SENDING MOISTURE OUR WAY...OR REMAIN SPLIT WHICH WOULD SEND THE
MOISTURE TO OUR NORTH AND SOUTH.
TEMPERATURES THROUGH THE PERIOD WILL BE WARMEST ON WEDNESDAY BEFORE
THE COLD FRONT MOVES THROUGH. THROUGH THE REST OF THE WEEK
TEMPERATURES WILL BE ROUGHLY 10 DEGREES BELOW NORMAL AS THE COLD AIR
REMAINS OVER THE CWA. A BRIEF WARM UP WILL OCCUR SATURDAY...WITH
NEAR NORMAL TEMPERATURES BEFORE THE NEXT COLD FRONT MOVES
THROUGH.
JTL
&&
.AVIATION...
1007 AM MST SUN NOV 27 2011
FOR THE 18Z TAFS...VFR THROUGH THE PERIOD. WINDS WILL BE LIGHT AND
FROM THE WEST/NORTHWEST AS HIGH PRESSURE BUILDS IN. A FEW HIGH
CLOUDS CAN BE EXPECTED...ESPECIALLY LATER IN THE PERIOD.
BAS
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
345 PM EST SUN NOV 27 2011
.SYNOPSIS...
HIGH PRESSURE SLOWLY EDGES OFF THE COAST THROUGH MONDAY. AN AREA OF
LOW PRESSURE WILL DEVELOP OVER THE DEEP SOUTH BY EARLY MONDAY AND WILL
AFFECT THE MID ATLANTIC STATES LATE MONDAY NIGHT AND TUESDAY. HIGH
PRESSURE RETURNS FOR THE MIDDLE AND LATER HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY NIGHT/...
SATELLITE CONTINUES TO SHOW BANDS OF CU TRYING TO LIFT NORTHWARD
AS THE LOW LEVEL MOISTURE CONTINUES TO INCREASE IN THE SOUTHERLY
FLOW. THIS PATTERN OF SOUTHERLY FLOW WILL CONTINUE THROUGH MONDAY
NIGHT AS THE SURFACE HIGH CONTINUES TO SLIDE OFF INTO THE WESTERN
ATLANTIC AND THE UPPER TROUGH DIGS INTO THE LOWER MISSISSIPPI
BEFORE CLOSING OFF. WITH THE INCREASING OF THE LOW LEVEL
MOISTURE...EXPECT TO SEE A GRADUAL INCREASE IN THE CLOUDS TONIGHT
THROUGH THE DAY ON MONDAY WITH THE MOST CLOUDS IN THE THE LEE OF
THE PIEDMONT WITH THE TURNING OF THE FLOW TO THE SE. THE MID LEVEL
REMAIN DRY SO DO NOT SEE ANY CHANCE OF RAIN TONIGHT OR MONDAY. ON
MONDAY NIGHT AS THE UPPER LOW BEGINS TO LIFT NEWD AND THE SURFACE
FRONT BEGINS ITS APPROACH...COULD BEGIN TO SEE SOME SHOWERS
DEVELOP IN ADVANCE OF THE FRONT...BUT NOT ANTICIPATING MUCH
ACTIVITY UNTIL AFTER 6Z TUES.
FOR TEMPERATURES...WITH THE MOIST SOUTHERLY FLOW
CONTINUING...SHOULD SEE THE MILD READINGS CONTINUE. DID ALLOW FOR
SOME RADIATIONAL COOLING TONIGHT...BUT AGAIN IT WILL NOT BE AS
COOL AS PREVIOUS NIGHTS SO LOWS IN THE UPPER 40S TO THE LOWER 50S
SHOULD BE THE NORM. HIGHS TOMORROW WILL BE WARM AGAIN IN THE UPPER
60S TO LOWER 70S. CLOUDS COULD LIMIT THE HEATING SOME...BUT BEING
IN THE WARM SECTOR...THERE SHOULD BE SOME SUN SHINE AROUND. WITH
THE APPROACH OF THE FRONT AND THICKENING CLOUDS TEMPS WILL STAY UP
IN THE MID 50 TO AROUND 60 MONDAY NIGHT AS THE MOISTURE CONTINUES
TO INCREASE.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
GOING WITH A COMBINATION OF THE 12Z GFS...NAM...AND ECMWF MDLS WITH
REGARD TO TIMING OF FRNTL BNDRY AND ASSOC SHOWERS MOVNG ACRS THE
REGION DURING TUE. ONLY VRY WEAK INSTABILITY EXPECTED DURING TUE
EVEN THO TEMPS CLIMB INTO THE MID 60S OVR ERN PORTIONS OF THE AREA.
SO...SLGT CHC OF THUNDER IS ENOUGH. BULK OF PCPN WILL END GENERALLY
FM W TO E LATER TUE AFTN INTO TUE EVENG...AS FRNTL BNDRY EVENTUALLY
SLIDES OFF THE CST. MOST AREAS CUD RECEIVE BETWEEN .25 TO .50 INCH
OF RAINFALL WITH THIS SYSTEM...WITH HIER AMTS ACRS THE NRN CNTIES.
SLGT OR SML CHC OF SHOWERS...MAINLY OVR NRN THIRD OF THE AREA...WILL
LINGER LATE TUE NGT THRU WED...AS UPR LO LIFTS FM W.VA NNE INTO SE
CANADA. OTHRWISE...SHUD SEE A PRTLY SNY SKY ON WED. HIGHS ON TUE IN
THE UPR 50S TO MID 60S. LOWS TUE NGT IN THE UPR 30S TO LWR 40S.
HIGHS ON WED IN THE LWR TO MID 50S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
FOLLOWED CLOSE TO HPC BUT USED SOME ELEMENTS OF THE GFS/EURO. ON THE
HEELS OF A POTENT STORM SYSTEM...THE LONG TERM LOOKS DRY AND COOL.
AN ACTIVE NORTHERN STREAM WILL SEND SHORT WAVES THROUGH THE AREA BUT
THEY LOOK TO BE DRY. UPPER LEVEL HIGH OVER THE GULF OF MEXICO REGION
WILL NUDGE TOWARD THE SOUTHEAST STATES TOWARD NEXT WEEKEND. AT THE
SURFACE...POLAR HIGH PRESSURE WILL SLOWLY BUILD INTO THE AREA...
INTERRUPTED BY A REINFORCING COLD FRONT LATE FRIDAY.
HIGH TEMPERATURES WILL GENERALLY BE IN THE LOW TO MID 50S BUT
COOL TO THE MID 40S TO AROUND 50 ON SATURDAY. LOW TEMPERATURES WILL
BE MAINLY IN THE 30S...WITH SOME MID TO UPPER 20S WELL INLAND BY
SUNDAY MORNING.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS CONTINUE...BUT WITH THE SFC HIGH SLIDING OFF THE SE
COAST AND THE FRONTAL BOUNDARY HAVING MOVED INTO THE OHIO
VALLEY...THE PRESSURE GRADIENT HAS TIGHTENED. THIS IS LEADING TO
INCREASING SOUTHERLY WINDS...WHICH ARE GUSTING 20 TO 25 KTS.
EXPECT THIS TO CONTINUE THROUGH THE AFTERNOON HOURS. LOW LEVEL
MOISTURE CONTINUES TO WRAP AROUND THE SFC HIGH AND HAS REACHED THE
NC/VA BORDER. IT IS PRODUCING A CU FIELD AROUND 4K FT. THIS
MOISTURE WILL CONTINUE TO SPREAD NORTHWARD THIS EVENING INTO
MONDAY. A LITTLE CONCERNED THAT AS THE WINDS TURN A BIT MORE SE
COULD SEE SOME MVFR CEILINGS...BUT FOR NOW HAVE HELD CEILINGS
ABOVE 3K FT.
AFTER 18Z MONDAY...WILL SEE AN AREA OF LOW PRESSURE FORM ALONG THE
COLD FRONT OVER THE GULF COAST STATES ON MONDAY. THIS LOW MOVES
NORTHWARD INTO THE OHIO VALLEY WITH THE COLD FRONT SWINGING
THROUGH THE SERN US INTO THE MID ATLANTIC STATES TUESDAY. THIS
WILL RESULT IN SHOWERS WITH POSSIBLE MVFR CONDITIONS. THE FLOW
TURNS SWRLY BEHIND THE FRONT WHICH SHOULD BEGIN THE CLEARING
PROCESS WITH VFR CONDITIONS RETURNING.
&&
.MARINE...
SOUTHERLY WINDS WERE AROUND 15 KNOTS SUNDAY AFTN. SENSORS THAT ARE
NOT ELEVATED AND ARE AWAY FROM THE WESTERN SHORE OF THE BAY ARE
HOLDING WELL BELOW SCA CRITERIA. THE 18Z NAM AND RUC ARE HANDLING
THIS WELL AND INDICATE A DECREASE IN WINDS TOWARDS MIDNIGHT.
WINDS AND SEAS SHOULD STAY BELOW SCA CRITERIA UNTIL THE EARLY
MORNING HOURS OF TUESDAY (LATE MONDAY NIGHT) WHEN A SOUTHEAST FETCH
OVER THE COASTAL WATERS IS EXPECTED TO BRING 5 FOOT SEAS TO WITHIN
20 MILES OF OUR SHORE. SE WINDS WILL RUN AROUND 20 KNOTS OVER THE
BAY AND POSSIBLY CURRITUCK SOUND ON TUESDAY RESULTING IN THE
LIKELIHOOD OF SCA HEADLINES. WINDS TURN TO SW BY TUESDAY NIGHT AND
MAY INCREASE TO 20-25 KNOTS OVER THE COASTAL WATERS...ESPECIALLY
OVER NORTHERN PORTIONS. WINDS AND SEAS SHOULD DECREASE TO BELOW SCA
CRITERIA BY LATE WEDNESDAY.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ESS
NEAR TERM...ESS
SHORT TERM...TMG
LONG TERM...LSA
AVIATION...ESS
MARINE...LSA
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
229 PM EST SUN NOV 27 2011
.SYNOPSIS...
A SLOW MOVING STORM SYSTEM WILL BRING PERIODS OF SHOWERS
THROUGH MIDWEEK. MILD TEMPERATURES EARLY IN THE WEEK WILL COOL
SIGNIFICANTLY FOR THE LAST HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
2:30 PM UPDATE: ADJUSTED POP AND TEMPS TO BETTER FIT CURRENT TRENDS...
A SLOW MOVING FRONTAL SYSTEM OVER EASTERN OHIO AT
17Z IS CREATING SHOWERS ACROSS THE AREA AS IT MOVES VERY SLOWLY
EASTWARD. BY 06 UTC THE SYSTEM WILL BE ORIENTED FROM NW PA TO SE
OH...WITH WIDESPREAD SHOWERS ALONG AND WEST OF THE FRONT...AND BY
12 UTC THE FRONT WILL BE STATIONARY ACROSS THE SAME AREA WITH
WIDESPREAD SHOWERS BACKING SLIGHTLY TO THE WEST. USED THE HRRR TO
CREATE POP FIRST SEVERAAL HOURS OF THE FORECAST...AND THE SREF
THEREAFTER TO ACCOUNT FOR UNCERTAINTY. PRECIP AMOUNTS THROUGH
TONIGHT WILL RANGE FROM VERY LITTLE SOUTHEAST OF PIT...AROUND A
QUARTER INCH FOR THE PIT METRO...TO 1-1.50 INCHES ACROSS PORTIONS
OF EASTERN OHIO. CLOUDS...PRECIP...AND SOUTHERLY FLOW WILL KEEP
TEMPERATURES VERY MILD...WITH LOWS IN THE UPPER 40S TO LOWER 50S
ACROSS THE AREA.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
LOW PRESSURE IS EXPECTED TO DEVELOP ALONG THE SOUTHERN PORTION OF
THE FRONT OVER NORTHERN GA MONDAY MORNING...THEN MOVE NORTHWARD TO
A POSITION OVER CNTRL OH BY 12 UTC TUESDAY. THIS WILL BRING
WIDESPREAD SHOWERS BACK ACROSS THE AREA TUESDAY INTO TUESDAY
NIGHT. LOW PRESSURE IS FORECAST TO EJECT TO THE NORTHEAST
TUESDAY NIGHT/WEDNESDAY WITH PRECIP COVERAGE BECOMING MORE
SCATTERED BY WEDNESDAY MORNING. USED THE SREF TO CREATE POP TO
ACCOUNT FOR UNCERTAINTY THIS PERIOD. ADDITIONAL RAINFALL AMOUNTS
THROUGH WEDNESDAY WILL RANGE FROM 0.50-1.00 INCH ACROSS SOUTHWEST
PA AND POINTS EAST TO AROUND AN INCH ACROSS EASTERN OHIO. VERY
MILD TEMPERATURES WILL CONTINUE THROUGH MONDAY NIGHT...WITH VERY
LITTLE TEMPERATURE RISE ON TUESDAY. SHARPLY COLDER TEMPERATURES
ARE EXPECTED WEDNESDAY WITH SOME ACCUMULATING SNOWS POSSIBLE ON
THE RIDGES AS WRAP AROUND MOISTURE MOVES UP THE SLOPES....BUT
MOISTURE SEEMS LIMITED AT THIS TIME. THIS POTENTIAL MAY BE
HIGHLIGHTED IN LATER FORECASTS AS CONFIDENCE INCREASES.
&&
AVIATION /18Z SUNDAY THROUGH FRIDAY/...
MODELS IN FAIRLY GOOD AGREEMENT THAT COLD FRONT INITIALLY IN WESTERN
OHIO WILL DRIFT SLOWLY EAST OVER NEXT 12-18 HOURS BEFORE STALLING IN
THE VICINITY OF PA-OH BORDER. RADAR SHOWS AREAS OF LIGHT RAIN IN
EASTERN OHIO AND WESTERN PENNSYLVANIA DRIFTING EAST WITH GENERAL VFR
CONDITIONS. AFTER 03Z CONDITIONS WILL DETERIORATE TO MVFR THROUGH
MID MORNING.
FRONT WILL RETREAT NORTH AS STRONG LOW DEVELOPS ALONG THE FRONT
TOMORROW AND MOVES SLOWLY NORTHEAST. EXPECT CONDITIONS TO IMPROVE
TO VFR AFTER MID MORNING MONDAY THROUGH 00Z TUESDAY. BULK OF RAIN
WILL MOVE ACROSS AREA WEDNESDAY WITH AND IFR CONDITIONS WITH
PERIODS OF MODERATE TO HEAVY RAIN AND FOG. COLD AIR WILL MOVE INTO
REGION FROM SOUTHWEST WITH RAIN CHANGING TO SNOW SHOWERS IN MOST
LOCATIONS BY WEDNESDAY MORNING WITH MIXED RAIN AND SNOW SHOWERS
WEDNESDAY.
CONDITIONS IMPROVE TO VFR BY THURSDAY MORNING WITH HIGH PRESSURE
BUILDING INTO REGION. COLD FRONT WITH LIMITED MOISTURE WILL MOVE
ACROSS REGION FROM THE GREAT LAKES WITH MVFR CONDITIONS POSSIBLE
FROM 18Z FRIDAY THROUGH 06Z SATURDAY.
BEHIND FRONT VFR CONDITIONS FORECAST THROUGH THE WEEKEND.
.LONG TERM WEDNESDAY NIGHT THROUGH SUNDAY.
BY WEDNESDAY EVENING NORTHERLY FLOW BEHIND EXITING STORM IN NEW
ENGLAND MAY KEEP A FEW SHOWERS/FLURRIES OVER REGION EARLY. HIGH
PRESSURE WILL BUILD NORTHEAST TO WV BY THURSDAY MORNING BRINGING
DRIER AIR AND SUNSHINE. MODELS CONSISTENT WITH COLD MOVING
SOUTHEAST FROM GREAT LAKES ON FRIDAY WITH LIMITED MOISTURE. CHANCE
OF SHOWERS FROM MID DAY FRIDAY ON. BY SATURDAY BROAD WESTERLY FLOW
WILL BRING COLDER TEMPERATURES WITH LOWS IN THE 20S AND HIGHS IN THE
30S AND LITTLE THREAT OF PRECIPITATION FOR THE WEEKEND.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
213 PM EST SUN NOV 27 2011
.SYNOPSIS...
A SLOW MOVING STORM SYSTEM WILL BRING PERIODS OF SHOWERS
THROUGH MIDWEEK. MILD TEMPERATURES EARLY IN THE WEEK WILL COOL
SIGNIFICANTLY FOR THE LAST HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
2:15 PM UPDATE: A SLOW MOVING FRONTAL SYSTEM OVER EASTERN OHIO AT
17Z IS CREATING SHOWERS ACROSS THE AREA AS IT MOVES VERY SLOWLY
EASTWARD. BY 06 UTC THE SYSTEM WILL BE ORIENTED FROM NW PA TO SE
OH...WITH WIDESPREAD SHOWERS ALONG AND WEST OF THE FRONT...AND BY
12 UTC THE FRONT WILL BE STATIONARY ACROSS THE SAME AREA WITH
WIDESPREAD SHOWERS BACKING SLIGHTLY TO THE WEST. USED THE HRRR TO
CREATE POP FIRST SEVERAAL HOURS OF THE FORECAST...AND THE SREF
THEREAFTER TO ACCOUNT FOR UNCERTAINTY. PRECIP AMOUNTS THROUGH
TONIGHT WILL RANGE FROM VERY LITTLE SOUTHEAST OF PIT...AROUND A
QUARTER INCH FOR THE PIT METRO...TO 1-1.50 INCHES ACROSS PORTIONS
OF EASTERN OHIO. CLOUDS...PRECIP...AND SOUTHERLY FLOW WILL KEEP
TEMPERATURES VERY MILD...WITH LOWS IN THE UPPER 40S TO LOWER 50S
ACROSS THE AREA.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
LOW PRESSURE IS EXPECTED TO DEVELOP ALONG THE SOUTHERN PORTION OF
THE FRONT OVER NORTHERN GA MONDAY MORNING...THEN MOVE NORTHWARD TO
A POSITION OVER CNTRL OH BY 12 UTC TUESDAY. THIS WILL BRING
WIDESPREAD SHOWERS BACK ACROSS THE AREA TUESDAY INTO TUESDAY
NIGHT. LOW PRESSURE IS FORECAST TO EJECT TO THE NORTHEAST
TUESDAY NIGHT/WEDNESDAY WITH PRECIP COVERAGE BECOMING MORE
SCATTERED BY WEDNESDAY MORNING. USED THE SREF TO CREATE POP TO
ACCOUNT FOR UNCERTAINTY THIS PERIOD. ADDITIONAL RAINFALL AMOUNTS
THROUGH WEDNESDAY WILL RANGE FROM 0.50-1.00 INCH ACROSS SOUTHWEST
PA AND POINTS EAST TO AROUND AN INCH ACROSS EASTERN OHIO. VERY
MILD TEMPERATURES WILL CONTINUE THROUGH MONDAY NIGHT...WITH VERY
LITTLE TEMPERATURE RISE ON TUESDAY. SHARPLY COLDER TEMPERATURES
ARE EXPECTED WEDNESDAY WITH SOME ACCUMULATING SNOWS POSSIBLE ON
THE RIDGES AS WRAP AROUND MOISTURE MOVES UP THE SLOPES. THIS
POTENTIAL WILL BE HIGHLIGHTED IN LATER FORECASTS AS CONFIDENCE
INCREASES.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
RESIDUAL SNOW SHOWERS WILL END WEDNESDAY EVENING AS THE LOW
EXITS TO THE EAST. MAINLY DRY CONDITIONS WILL PREVAIL THURSDAY
UNDER LOW AMPLITUDE RIDGING. A WEAK FRONTAL BOUNDARY IS PROGGED
TO CLIP THE AREA FRIDAY/FRIDAY NIGHT FOR A LOW CHANCE OF RAIN/SNOW
SHOWERS. SATURDAY LOOKS MAINLY DRY. TEMPERATURES 5-10 DEGREES
BELOW NORMAL WILL PREVAIL.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS EXPECTED AT ALL PORTS THROUGH THE MORNING HOURS. A
COLD FRONT WILL SLOWLY MOVE ACROSS OHIO THIS AFTERNOON. FRONT WILL
THEN STALL OVER THE UPPER OHIO VALLEY TONIGHT.
AN AREA OF BKN-OVC MIDDLE CLOUDS WILL MOVE AHEAD OF THE FRONT AND
OVERSPREAD THE REGION BY THIS AFTERNOON. SOUTHERLY SFC WINDS WILL
BECOME GUSTY BY LATE MORNING AND CONTINUE THROUGH THE AFTERNOON.
EXPECT GUSTS AROUND 20KTS AT MOST PORTS. LLWS IS POSSIBLE LATER
TODAY AS A STRONG LL JET WILL MOVE ACROSS THE REGION. FOR NOW,
WILL NOT MENTION IN THE FORECAST, BUT THIS WILL NEED TO BE
REASSESSED LATER TODAY.
THE DIFFICULT PART OF THE FORECAST BEGINS LATER THIS EVENING,
ATTEMPTING TO TIME THE ONSET OF RESTRICTIONS AND HOW FAR AND HOW
FAST THESE WILL SPREAD EASTWARD.
FOR CURRENT FORECAST, WILL BRING RESTRICTIONS TO ZZV WITH RAIN
SHOWERS THIS EVENING. RESTRICTIONS MAY REACH ALSO FKL JUST AFTER
00Z.
OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...
PERIODS OF SHOWERS AND RESTRICTIONS WILL BE POSSIBLE AT ALL PORTS
THROUGH WEDNESDAY. ON MONDAY, SHOWERS SHOULD GENERALLY BE FROM
PITTSBURGH WEST, WITH THE MAIN RAIN SHIELD MOVING IN ON TUESDAY AND
TUESDAY NIGHT. EXPECT RESTRICTIONS TO CONTINUE INTO WEDNESDAY,
ALTHOUGH MOST OF THE PRECIPITATION WILL SHIFT NORTHWARD. VFR
EXPECTED ON THURSDAY UNDER HIGH PRESSURE.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GAYLORD MI
207 PM EST SUN NOV 27 2011
.SYNOPSIS.../ISSUED AT 1126 AM/
A COLD FRONT HAS DELIVERED A COOLER AIR MASS TO NORTHERN MICHIGAN.
LIGHT RAIN AND SNOW WILL GRADUALLY END FROM WEST TO EAST THIS
AFTERNOON. SOME LIGHT LAKE EFFECT RAIN OR RAIN/SNOW MIX WILL
DEVELOP TONIGHT...BUT PRECIPITATION AMOUNTS WILL BE VERY LIGHT. THERE
WILL BE A BRIEF BREAK FROM PRECIPITATION MONDAY...BUT THEN
PRECIPITATION CHANCES WILL RETURN TUESDAY...MAINLY SOUTHEAST OF
GAYLORD. TEMPERATURES WILL BE SEASONABLY COLD THIS UPCOMING WEEK.
TL/JH
&&
.SHORT TERM.../ISSUED AT 207 PM/...THIS AFTERNOON
...LIGHT SYNOPTIC RAIN/SNOW WILL GRADUALLY END WITH A MUCH MORE
SEASONABLE AIR MASS NOW ESTABLISHED FOR THE UPCOMING WEEK...
MESOSCALE UPDATE 207 PM: LAKE INSTABILITY IS ARRIVING FASTER THAN
EXPECTED PER APX 88D. LIGHT R/S SHWRS HAVE DEVELOPED OVER MUCH OF NW
LOWER. WILL AMEND THE FCST TO ACCOUNT FOR THIS. SLOW MOVEMENT OF
UPPER TROF HAS DEPLAYED THE EXIT OF DEEPER MSTR. SO DGZ WILL BE
SATURATED FOR A WHILE LONGER THAN PREVIOUSLY EXPECTED. STILL PLAN TO
TRANSITION TO ALL LIQUID NRN LOWER LATE THIS AFTN INTO TNGT.
PLEASE SEE CLIMATE SECTION FOR RECORD WARM LOW TEMPS SAT 11/26.
HIGHLY AMPLIFIED BUT SLOWLY PROGRESSIVE FLOW IS OVER THE CONUS. THE
MERIDIONAL UPPER TROF /NESTLED BETWEEN 2 SUBTROPICAL RIDGES/ HAS
ADVANCED FROM THE PLAINS TOWARD THE MS RIVER VALLEY IN THE PAST 24
HRS...WITH ITS WAVELENGTH DECREASING. THIS TROF WILL BEGIN
BIFURCATING TODAY WITH THE PORTION AFFECTING THE GTLKS REMAINING
PROGRESSIVE.
THE ASSOCIATED ANABATIC COLD FRONT WAS E OF THE FCST AREA...
EXTENDING FROM A 1002 MB LOW S OF JAMES BAY...TO LAKE HURON...TO
THE THUMB. NNW WINDS UP TO 30 KTS WILL CONTINUE ADVECTING COOLER
SEASONABLE AIR IN THE AREA.
SYNOPTIC PCPN: BACK EDGE OF PCPN SHIELD HAS CHANGED OVER TO SNOW AND
WILL END FROM NW TO SE THIS AFTN WITH NO ACCUM.
88D CORRELATION COEFFICIENT SHOWS R/S LINE PROGRESSING SEWD...
CONFIRMED BY TRANSITION HERE AT OFFICE AND SPOTTER REPORTS.
BACK EDGE OF PCPN LINES UP WITH DEEP MSTR. SO ONCE -SN ENDS THE DGZ
DRIES OUT PER RUC FCST SOUNDINGS. SO EXPECT PCPN TO END OVER NRN
LOWER. SHOULD SEE CHANGOVER TO -SN ALL THE WAY TO LAKE HURON/SAGINAW
BAY. UPSTREAM PIREPS CONFIRM SATL AND 12Z 700 CHART MID-LEVEL
DRYING. CLOUD TOPS ARE 4-6K FT UPSTREAM.
LAKE EFFECT PCPN: THE MQT 88D IS ALREADY SHOWING LAKE DEVELOPMENT ON
SUPERIOR AS LOW-LEVEL THERMAL PROFILE /INSTABILITY/ IS SUPPORTIVE.
IT WILL TAKE UNTIL 21Z FOR CAA TO ADVECT FAVORABLE LAPSE RATES INTO
NW LOWER. HOWEVER...FRONTAL INVERSION WILL CAP LAKE CLOUDS TO 850 MB.
AM NOT EXPECTING MUCH MORE THAN WIDESPREAD CLOUDS AS THE DGZ NEVER
RE-SATURATES.
IT WILL BE MOIST UP TO 850. SO NW FLOW INTO HIGHER TERRAIN SHOULD
PRODUCE SOME DRIZZLE.
OVER THE EASTERN U.P. EXPECTED R SHWRS TO POSSIBLY MIX WITH SNOW
LATE...AS INVERSION DEEPENS JUST ENOUGH TO ICE CRYSTALS TO DEVELOP.
BUT IT MAY NOT BE ENUF FOR SNOW.
THIS HAS NECESSITATED CHANGES TO THE FCST ISSUED AT 403 AM. BROUGHT
SNOW TO AN END AS DEEP MSTR DEPARTS...AND CHANGED R TO S BEFORE
ENDING SE OF GAYLORD. ALL LAKE PCPN OVER THE U.P. HAS BEEN CHANGED
FROM S TO A R/S MIX. ALL SNOW HAS BEEN REMOVED FROM THE FCST FOR NRN
LOWER. WHAT MINISCULE SNOWFALL AMTS WERE FCST HAVE BEEN ZERO`D OUT.
TEMPS WILL CONTINUE FALLING ANOTHER 4-7F ALONG LAKE HURON/SAGINAW
BAY. ELSEWHERE...TEMPS WILL HOLD STEADY THE REST OF THE DAY.
DUAL POL PCPN ESTIMATES: THIS IS OUR FIRST PCPN EVENT SINCE
RETURNING TO SERVICE WITH DUAL POL. OVERALL PCPN ESTIMATES ARE
SUPERIOR TO THE LEGACY ALGORITHM. LEGACY WAS GENERALLY TOO LOW.
THE MAIN DISAGREEMENT WAS OVER BENZIE/MANISTEE COUNTIES WHERE AN
AVERAGE OF THE TWO WAS THE BEST. DUAL POL ACCUMULATION WAS WAY TO
HIGH BY UP TO 2 TIMES...MOST LIKELY DUE TO MELTING ISSUES.
HALBLAUB
&&
.LONG TERM.../ISSUED AT 417 AM/...TONIGHT AND BEYOND
SOME QUIETER WX FOR A DAY OR SO...AS HIGH PRESSURE WEDGES IN
OVERHEAD BETWEEN SYSTEMS IN THE DEEP SOUTH AND UP BY HUDSON BAY.
MODELS HAVE TRENDED WESTWARD WITH THE EJECTING SOUTHERN LOW BY
TUESDAY...AND AS THE PREVIOUS SHIFT NOTED WE MAY GET CLIPPED BY THE
BROAD PRECIP SHIELD NW OF THIS SYSTEM...PERHAPS AS SOON AS LATE
MONDAY NIGHT. PRECIP TRENDS (INCLUDING PRECIP TYPE) ARE THE MAIN
CONCERN.
MODELS...HEY...ANOTHER TWO-CAMP SOLUTION. THIS TIME THE GFS/UKMET
ARE IN A MORE NORTHERLY CAMP WITH THE EJECTING SOUTHERN UPPER LOW
(EASTERN OHIO TUESDAY EVENING)...WHICH WOULD RESULT IN WETTER WX
HERE. THE OPERATIONAL GFS OFFERS THE MOST DIRE SOLUTION.
MEANWHILE...THE NAM...ECMWF...AND GEM ARE MORE SOUTHERLY (TN/NC/VA
BORDER AREA) AND DRIER. HPC RECOMMENDS HEDGING OUR BETS WITH A
GFS/ECMWF COMPROMISE...WHICH SEEMS A REASONABLE APPROACH UNTIL
THINGS GETS FURTHER NAILED DOWN.
TONIGHT/MONDAY...MODELS HAVE TRENDED COLDER TONIGHT...WITH 850MB
TEMPS OF -9C LINGERING TO AROUND MIDNIGHT (DELTA T/S 15-16). WILL
ADJUST POPS TONIGHT HIGHER...WITH A SMALL AREA OF LIKELY POPS IN
BOTH PENINSULAS IN NW/NNW SNOWBELTS. AM A LITTLE CONCERNED WE COULD
MANAGE SOME SNEAKY 1-2 INCH ACCUMS...ESPECIALLY GIVEN THE SOLID
SUPERIOR CONNECTION INTO NW LOWER. BUT WE WON/T HAVE MUCH TIME FOR
CONVECTION TO RECOVER/REORGANIZE AFTER DIURNAL DISRUPTIONS...BEFORE
THE 850MB THERMAL TROF LIFTS OUT TO THE NE OVERNIGHT. BY 12Z...850MB
TEMPS WILL BE DOWN TO THE -4/-5C RANGE...AND THERE SHOULDN/T BE ANY
PRECIP LEFT FOR MONDAY. SKIES WILL TEND TO CLEAR MONDAY...WITH HIGH
PRESSURE OVERHEAD AND A NARROW WEDGE OF SHARP SUBSIDENCE (850-700MB
RH GOES BELOW 20 PERCENT). SOME MID/HIGH CLOUDS WILL LINGER NEAR
SAGINAW BAY.
MIN TEMPS IN THE 20S TONIGHT...WITH SOME UPPER TEENS POSSIBLE IN
INTERIOR SECTIONS OF NE LOWER MI. MAX TEMPS UPPER 30S TO AROUND 40F.
MONDAY NIGHT/TUESDAY...A NORTHERN STREAM SHORTWAVE WILL MAKE
EASTWARD PROGRESS ACROSS NORTHERN MN MONDAY NIGHT...AND THEN WILL
WASH OUT AS THE LARGER CIRCULATION TO THE SOUTH AND SE TAKES OVER.
BAND OF F-GEN AND ASSOCIATED MID CLOUDS AHEAD OF THIS WAVE WILL
REACH EASTERN UPPER MI BY DAWN TUESDAY...PRODUCING VIRGA AND MAYBE A
FLURRY.
THE BIGGER CONCERN IS THE DEEP LOW TO THE SOUTH. MODEL DIFFS ARE
RELATIVELY MINOR THRU 12Z TUESDAY...WITH RAIN DEFINITELY MOVING INTO
SE LOWER MI...AND NAM/GFS BOTH TRY TO BACK UP PRECIP TOWARD SAGINAW
BAY. WILL MAINTAIN A CHANCE OF RAIN IN THE SE ZONES (ALL PRECIP
LIQUID THERE...WITH 850MB TEMPS 3-4C...AND SURFACE TEMPS IN THE MID
30S. ALL MODELS CONTINUE TO SLOWLY EXPAND PRECIP NORTHWARD AS THE
UPPER LOW LOVES UP THE TN VALLEY AND CENTRAL APPALACHIANS. WILL
BOOST AND EXPAND POPS...WITH LIKELY POPS ALONG/SE OF HTL-APN...AND
CATEGORICAL NEAR TAWAS/STANDISH. THIS WILL ALMOST ALL LIQUID...WITH
ABOVE FREEZING 850MB AND SURFACE TEMPS IN MOST OF THE PRECIP AREA.
HOWEVER...ALONG THE OUTER EDGE OF THE PRECIP SHIELD...850MB TEMPS
WILL DROP SLIGHTLY BELOW ZERO...AND THE SURFACE-BASED WARM LAYER
WILL SHRINK BELOW 1K FEET. WILL MENTION A RAIN/SNOW MIX ALONG THE NW
EDGE (MANISTEE TO CHEBOYGAN).
MIN TEMPS UPPER 20S TO AROUND 30 IN MOST PLACES...EXCEPT LOW/MID 30S
FAR SE. MAX TEMPS MID 30S TO LOWER 40S.
REST OF THE FORECAST...FORECAST RAPIDLY TURNS MORE INTERESTING TUE
NIGHT. AS THE SURFACE LOW PASSES BY TO THE EAST...COLD
ADVECTION FROM 850MB ON DOWN WILL RAPIDLY TURN PRECIP FROM RAIN TO
SNOW. PRECIP WILL BE DWINDLING LATE TUE NIGHT AND OUT OF THE PICTURE
COMPLETELY BY MIDDAY WEDNESDAY. WILL INCREASE POPS TUESDAY
NIGHT...INCLUDING ADDING SOME LIKELY POPS IN NE LOWER (RAIN/SNOW MIX
IN THE EVENING...ALL SNOW OVERNIGHT). SNOW POTENTIAL VARIES GREATLY
FROM MODEL TO MODEL...AS THEY DIFFER ON BOTH PRECIP PRODUCTION (GFS
IS QUITE WET...UP TO AN INCH OF QPF TUE NIGHT IN NE LOWER)...AND ON
HOW QUICKLY TO TURN PRECIP TO SNOW. CERTAINLY POTENTIAL IS THERE FOR
MODERATE (ADVISORY-LEVEL) ACCUMS...PERHAPS EVEN MORE IN A WORST-CASE
SCENARIO.
JZ
&&
.MARINE.../ISSUED AT 1126 AM/
AT 11 AM...ADDED THE STRAITS TO THE SCA. OTHERWISE ALL OTHER SCA
HEADLINES REMAIN AS IS FROM 405 AM ISSUANCE.
COLD FRONT HAS EXITED THE WATERS SURROUDNING NRN MI. NW- NNW
GUSTS WILL CONTINUE 25-30KT IN MOST PLACES WELL.
HALBLAUB
WINDS WILL DIMINISH LATE TONIGHT INTO MONDAY AS HIGH PRESSURE
BRIEFLY SETTLES INTO THE LAKES REGION.
JZ
&&
.AVIATION.../ISSUED AT 207 PM/...VALID FOR 18Z TAFS
COLD FRONT HAS DEPARTED THE REGION AND COOLER AIR MASS NOW
ESTABLISHED. LARGE-SCALE LGT PCPN IS ENDING AND PATTERN IS
TRANSITIONING TO LGT LAKE EFFECT RA/SN SHWRS FOR TVC/PLN/MBL. LAKE
EFFECTS WILL END MON WITH CIGS IMPROVING TO LOW-END VFR. CONFIDENCE
IS HIGH ON OCCURRENCE BUT LOW ON TIMING OF TRANSITION TO VFR.
REST OF THIS AFTN: 1200-1500 FT MVFR CIGS WILL LIFT TO 2000-2800 FT.
VSBYS MOSTLY UNRESTRICTED BUT BRIEF REDUCTION TO MVFR POSSIBLE IN AN
HEAVIER RA/SN SHWRS. NW WINDS WILL AVERAGE 10-15 KTS WITH AN
OCCASIONAL G20.
TNGT: MVFR 2000-3000 FT CIGS. AN OCCASIONAL -SHRA OR -DZ WILL REMAIN
POSSIBLE PLN/TVC/MBL...ESPECIALLY BEFORE 06Z. NW WINDS WILL DIMINISH
BELOW 10 KTS AND PROBABLY TURN CALM OR VRB03 BY 09Z.
MON THRU 18Z: ANY LEFTOVER MVFR CIGS LIFT AND BECOME VFR SCT-BKN
3500 FT. LIGHT WINDS.
HALBLAUB
&&
.CLIMATE.../ISSUED AT 1126 AM/
RECORDS: ALL LONG-TERM CLIMATE SITES EXCEPT SSM SET/TIED THE WARMEST
LOW TEMPS ON RECORD YESTERDAY.
APN 45F (OLD RECORD 41 IN 1948)
GLR 46F (OLD RECORD 39 IN 2009)
HTL 48F (OLD RECORD 43 IN 2006)
TVC 50F (TIED OLD RECORD 50 IN 1915)
HALBLAUB
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 5 AM EST MONDAY FOR LHZ345-347-348.
LM...SMALL CRAFT ADVISORY UNTIL 5 AM EST MONDAY FOR LMZ323-342-
344>346.
LS...SMALL CRAFT ADVISORY UNTIL 5 AM EST MONDAY FOR LSZ321.
&&
$$
WFO APX
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1236 PM EST SUN NOV 27 2011
UPDATED AVIATION DISCUSSION FOR 18Z TAFS
.UPDATE...
IT HAS BEEN A STRUGGLE TO SEE LES DEVELOPMENT THIS MORNING...MOST
LIKELY DUE TO THE VERY STRONG SUBSIDENCE INVERSION NOTED ON THE 12Z
INL SOUNDING AND NEUTRAL TO JUST SLIGHTLY CYCLONIC PBL FLOW. HAVE
SEEN SOME BETTER BANDING BETWEEN MARQUETTE AND MUNISING IN THE LAST
FEW HOURS MOST LIKELY OWED TO SLIGHT ENHANCEMENT FROM LAKE NIPIGON
AND FROM BEING ON THE WESTERN EDGE OF THE MID LEVEL CLOUDS. WITH
THAT BEING SAID...HAVE RAISED POPS THIS MORNING IN WESTERN ALGER
COUNTY TO CATEGORICAL AND ALSO RAISED ACCUMULATIONS TO UP TO 3
INCHES WELL INLAND OF LAKE SUPERIOR. IF NOTHING ELSE...SOME
UNTREATED ROADS WILL BECOME A LITTLE SLIPPERY IN THIS AREA ALONG THE
M-94 CORRIDOR BETWEEN SKANDIA AND WETMORE.
OTHERWISE...WITH THE DRY AIR AND BUILDING HEIGHTS MOVING INTO
WESTERN UPPER MI BY THIS AFTN...HAVE OPTED TO JUST GO WITH SCATTERED
SNOW SHOWERS FOR THE REMAINDER OF THE DAY IN THIS AREA.
IN ADDITION...TEMPS WILL STRUGGLE TO RISE MUCH TODAY DUE TO CLOUD
COVER AND COLD ADVECTION. WILL GENERALLY GO WITH STEADY TEMPS IN THE
UPPER 20S WEST AND MID 30S EAST.
&&
.SYNOPSIS /ISSUED AT 442 AM/...
WV IMAGERY AND RUC ANALYSIS INDICATED A HIGH AMPLITUDE PATTERN WITH
A MID/UPPER LEVEL RIDGE OVER THE WRN CONUS AND A TROUGH OVER THE
CNTRL CONUS FROM NW ONTARIO TO CNTRL TX. THE BACK EDGE OF THE DEEPER
MOISTURE WAS MOVING STEADILY EASTWARD AND WAS NEAR A INL-MSP LINE.
AT THE SFC...LOW PRES NE OF LAKE SUPERIOR CONTINUED TO LIFT OFF TO
THE NE THROUGH NRN ONTARIO. CAA IN THE WAKE OF THE LOW HAD DROPPED
850 MB TEMPS TO NEAR -10C OVER WRN LAKE SUPERIOR. EVEN THOUGH
KINL/CYPL SOUNDINGS INDICATED A MOISTURE PROFILE THROUGH LOW AND MID
LEVELS FAVORABLE FOR LAKE EFFECT SNOW...WITH ONLY MARGINAL
INSTABILITY (LK-H8 DELTA/T TO 15C)AND THE CLOUD LAYER BLO THE DGZ
LAYER (10K-14K FT) SNOW HAS BEEN RELATIVELY LIGHT. BRIEF PERIODS OF
LAKE ENHANCED SNOW AT IWD AND AT NWS MQT HAVE RESULTED IN A LIGHT
COATING OF SNOW. IR LOOP SHOWED THE BACK EDGE OF THE LOW CLOUDS TO
NEAR THE MN/DAKOTAS BORDER.
&&
.DISCUSSION...
TODAY AND TONIGHT...EXPECT SCT/NMRS LIGHT LAKE EFFECT SNOW SHOWERS
TO CONTINUE FOR LOCATIONS FAVORED BY NNW FLOW. THE RELATIVELY SHORT
FETCH LENGTH INTO THE WEST WILL LIMIT ACCUMULATION POTENTIAL. THE
LOCAL HIGH RES WRF/ARW SUGGESTS THAT UPSTREAM CONDITIONING FROM LAKE
NIPIGON AND SLIGHTLY MORE N THAN NNW FLOW MAY SUPPORT LES BANDS INTO
NORTH CENTRAL UPPER MI. THE LATER ARRIVAL OF THE COLD AIR INTO THE
EAST TIL THE AFTER THE MOISTURE DEPARTS WILL ALSO BE UNFAVORABLE FOR
ANY SIGNIFICANT ACCUMULATIONS. THE LES SHOULD DIMINISH DURING THE
AFTERNOON AS 800-700 MB DRYING MOVE IN. OVERALL...GIVEN THE LACK OF
SYNOPTIC SCALE UPWARD MOTION WITH THE MARGINAL INSTABILITY...ONLY
MINOR ACCUMULATIONS OF AN INCH OR LESS ARE EXPECTED.
TONIGHT...ANY REMAINING LES WILL GRADUALLY END AS SFC AND MID LEVEL
RIDGING BUILD INTO THE THE REGION WITH ACYC FLOW AND INVERSION
HEIGHTS FALLING TO AROUND 3K FT. WITH FAVORABLE RADIATIONAL COOLING
CONDITIONS INLAND OVERNIGHT...MIN TEMPS WILL FALL INTO THE MID TEENS
WHILE LAKE CLOUDS KEEP TEMPS INT THE MID 20S EAST.
MONDAY INTO TUE...MDLS WERE IN REASONABLE AGREEMENT WITH A NRN
STREAM SHORTWAVE TROUGH MOVING INTO MANITOBA MON AND THROUGH NRN
ONTARIO EARLY TUE WHICH WILL DRAG A COLD FRONT THROUGH LAKE
SUPERIOR. WITH LITTLE MOISTURE AVAILABLE ONLY WEAK DYNAMICS ON
THE SRN TAIL OF THE SHRTWV...NO MEASURABLE PCPN IS EXPECTED. WITH SW
LOW LEVEL WAA AND SUNSHINE AHEAD OF THE TROUGH ON MON...TEMPS WILL
REBOUND INTO THE UPPER 30S TO AROUND 40. WITH ONLY MODERATE CAA
BEHIND THE FRONT AND A RELATIVELY DRY AIRMASS 850 MB TEMPS TO AROUND
-6C WILL NOT BE LOW ENOUGH TO PRODUCE LES. PCPN ASSOCIATED WITH THE
CUTOFF LOW ALSO WILL REMAIN EAST OF THE AREA TUE AS DRY NRLY FLOW
(PWAT DOWN TO NEAR 0.10 INCH) DOMINATES THE AREA.
WED THROUGH SAT...THE GFS/ECMWF/GEM WERE CONSISTENT IN SHOWING TREND
TOWARD TROUGHING INTO THE CNTRL CONUS AS A RIDGE BUILDS OVER THE ERN
PACIFIC. WITH THIS PATTERN...COLDER WILL MOVE INTO THE GREAT LAKES
WITH POTENTIAL FOR SOME LES. TIMING IS UNCERTAIN...BUT GFS/ECMWF
CONSENSUS SUGGESTS THAT A SHORTWAVE WILL MOVE THROUGH THU WITH 850 MB
TEMPS FALLING TO NEAR -13C BY LATE THU INTO THU NIGHT. EVEN THOUGH
THIS SHOULD PROVIDE ENOUGH INSTABILITY FOR LES...FCST DRY 850-700 MB
MOISTURE WILL BE UNFAVORABLE FOR SIGNIFICANT ACCUMULATIONS. A
PROGRESSIVE NRN STREAM FLOW WOULD LEAD TO WAA FRI INTO SAT WITH
RECOVERING TEMPS AND MAINLY DRY WEATHER.
&&
.AVIATION...
GUSTY NORTH TO NORTHWEST FLOW WILL KEEP MVFR CIGS AT ALL TERMINALS
THROUGH THIS EVENING. ALTHOUGH THERE HAVE BEEN LAKE EFFECT SNOW
SHOWERS...THE BEST HAVE BEEN EAST OF SAWYER WITH VERY FEW AT CMX AND
IWD. WITH MVFR TYPE CIGS AS FAR WEST AS FARGO...IT WILL TAKE SOME
TIME FOR CLEARING TO MOVE INTO UPPER MICHIGAN. IN FACT...VFR CIGS
WILL PROBABLY NOT OCCUR UNTIL MIDNIGHT OR AFTER FOR THE REGION AS
THE HIGH BUILDS IN. THE HIGH SHIFTS SOUTHEAST OF THE AREA ON MONDAY
ALLOWING FOR SOUTHERLY WINDS TO DEVELOP AHEAD OF ANOTHER WEAK COLD
FRONT.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
EXPECT N TO NW WINDS UP TO 30 KTS WITH A FEW GALE FORCE GUSTS TO 35
KTS TO DIMINISH THIS AFTERNOON WITH THE APPROACH OF HI PRES FROM
MINNESOTA. LIGHT WINDS TONIGHT WITH THE PASSAGE OF THE HI WILL GIVE
WAY TO A STRONGER SW FLOW ON MON AS THE PRES GRADIENT SHARPENS
BETWEEN THE HI DRIFTING INTO THE LOWER LAKES AND ANOTHER APPROACHING
COLD FRONT. LOOK FOR A WSHFT TO THE N BEHIND THIS FRONT ON MON NIGHT
AND STRENGTHENING WINDS MAINLY OVER THE E HALF INTO TUE ON THE NW
FLANK OF A DEEP LO PRES MOVING THRU THE LOWER GREAT LAKES INTO
ONTARIO. DEPENDING ON HOW FAR W THIS LO DRIFTS...N GALES TO 35 KTS
ARE POSSIBLE OVER PORTIONS OF THE E HALF. THE STRONGER WINDS WILL
DIMINISH TUE NIGHT THRU WED WITH THE APPROACH OF ANOTHER HI PRES
SYSTEM...BUT A STRONGER NW FLOW WILL DEVELOP ON THU IN THE WAKE OF
ANOTHER COLD FROPA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MRD
SYNOPSIS...JLB
DISCUSSION...JLB
AVIATION...MRD
MARINE...KC
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1127 AM EST SUN NOV 27 2011
.SYNOPSIS.../ISSUED AT 1126 AM/
A COLD FRONT HAS DELIVERED A COOLER AIR MASS TO NORTHERN MICHIGAN.
LIGHT RAIN AND SNOW WILL GRADUALLY END FROM WEST TO EAST THIS
AFTERNOON. SOME LIGHT LAKE EFFECT RAIN OR RAIN/SNOW MIX WILL
DEVELOP TONIGHT...BUT PRECIPITATION AMOUNTS WILL BE VERY LIGHT. THERE
WILL BE A BRIEF BREAK FROM PRECIPITATION MONDAY...BUT THEN
PRECIPITATION CHANCES WILL RETURN TUESDAY...MAINLY SOUTHEAST OF
GAYLORD. TEMPERATURES WILL BE SEASONABLY COLD THIS UPCOMING WEEK.
TL/JH
&&
.SHORT TERM.../ISSUED AT 1126 AM/...THIS AFTERNOON
...LIGHT SYNOPTIC RAIN/SNOW WILL GRADUALLY END WITH A MUCH MORE
SEASONABLE AIR MASS NOW IN PLACE...
ALL UPDATED PUBLIC PRODUCTS AND RER`S HAVE POSTED. SEE CLIMATE
SECTION.
HIGHLY AMPLIFIED BUT SLOWLY PROGRESSIVE FLOW IS OVER THE CONUS. THE
MERIDIONAL UPPER TROF /NESTLED BETWEEN 2 SUBTROPICAL RIDGES/ HAS
ADVANCED FROM THE PLAINS TOWARD THE MS RIVER VALLEY IN THE PAST 24
HRS...WITH ITS WAVELENGTH DECREASING. THIS TROF WILL BEGIN
BIFURCATING TODAY WITH THE PORTION AFFECTING THE GTLKS REMAINING
PROGRESSIVE.
THE ASSOCIATED ANABATIC COLD FRONT WAS E OF THE FCST AREA...
EXTENDING FROM A 1002 MB LOW S OF JAMES BAY...TO LAKE HURON...TO
THE THUMB. NNW WINDS UP TO 30 KTS WILL CONTINUE ADVECTING COOLER
SEASONABLE AIR IN THE AREA.
SYNOPTIC PCPN: BACK EDGE OF PCPN SHIELD HAS CHANGED OVER TO SNOW AND
WILL END FROM NW TO SE THIS AFTN WITH NO ACCUM.
88D CORRELATION COEFFICIENT SHOWS R/S LINE PROGRESSING SEWD...
CONFIRMED BY TRANSITION HERE AT OFFICE AND SPOTTER REPORTS.
BACK EDGE OF PCPN LINES UP WITH DEEP MSTR. SO ONCE -SN ENDS THE DGZ
DRIES OUT PER RUC FCST SOUNDINGS. SO EXPECT PCPN TO END OVER NRN
LOWER. SHOULD SEE CHANGOVER TO -SN ALL THE WAY TO LAKE HURON/SAGINAW
BAY. UPSTREAM PIREPS CONFIRM SATL AND 12Z 700 CHART MID-LEVEL
DRYING. CLOUD TOPS ARE 4-6K FT UPSTREAM.
LAKE EFFECT PCPN: THE MQT 88D IS ALREADY SHOWING LAKE DEVELOPMENT ON
SUPERIOR AS LOW-LEVEL THERMAL PROFILE /INSTABILITY/ IS SUPPORTIVE.
IT WILL TAKE UNTIL 21Z FOR CAA TO ADVECT FAVORABLE LAPSE RATES INTO
NW LOWER. HOWEVER...FRONTAL INVERSION WILL CAP LAKE CLOUDS TO 850 MB.
AM NOT EXPECTING MUCH MORE THAN WIDESPREAD CLOUDS AS THE DGZ NEVER
RE-SATURATES.
IT WILL BE MOIST UP TO 850. SO NW FLOW INTO HIGHER TERRAIN SHOULD
PRODUCE SOME DRIZZLE.
OVER THE EASTERN U.P. EXPECTED R SHWRS TO POSSIBLY MIX WITH SNOW
LATE...AS INVERSION DEEPENS JUST ENOUGH TO ICE CRYSTALS TO DEVELOP.
BUT IT MAY NOT BE ENUF FOR SNOW.
THIS HAS NECESSITATED CHANGES TO THE FCST ISSUED AT 403 AM. BROUGHT
SNOW TO AN END AS DEEP MSTR DEPARTS...AND CHANGED R TO S BEFORE
ENDING SE OF GAYLORD. ALL LAKE PCPN OVER THE U.P. HAS BEEN CHANGED
FROM S TO A R/S MIX. ALL SNOW HAS BEEN REMOVED FROM THE FCST FOR NRN
LOWER. WHAT MINISCULE SNOWFALL AMTS WERE FCST HAVE BEEN ZERO`D OUT.
TEMPS WILL CONTINUE FALLING ANOTHER 4-7F ALONG LAKE HURON/SAGINAW
BAY. ELSEWHERE...TEMPS WILL HOLD STEADY THE REST OF THE DAY.
DUAL POL PCPN ESTIMATES: THIS IS OUR FIRST PCPN EVENT SINCE
RETURNING TO SERVICE WITH DUAL POL. OVERALL PCPN ESTIMATES ARE
SUPERIOR TO THE LEGACY ALGORITHM. LEGACY WAS GENERALLY TOO LOW.
THE MAIN DISAGREEMENT WAS OVER BENZIE/MANISTEE COUNTIES WHERE AN
AVERAGE OF THE TWO WAS THE BEST. DUAL POL ACCUMULATION WAS WAY TO
HIGH BY UP TO 2 TIMES...MOST LIKELY DUE TO MELTING ISSUES.
HALBLAUB
&&
.LONG TERM.../ISSUED AT 417 AM/...TONIGHT AND BEYOND
SOME QUIETER WX FOR A DAY OR SO...AS HIGH PRESSURE WEDGES IN
OVERHEAD BETWEEN SYSTEMS IN THE DEEP SOUTH AND UP BY HUDSON BAY.
MODELS HAVE TRENDED WESTWARD WITH THE EJECTING SOUTHERN LOW BY
TUESDAY...AND AS THE PREVIOUS SHIFT NOTED WE MAY GET CLIPPED BY THE
BROAD PRECIP SHIELD NW OF THIS SYSTEM...PERHAPS AS SOON AS LATE
MONDAY NIGHT. PRECIP TRENDS (INCLUDING PRECIP TYPE) ARE THE MAIN
CONCERN.
MODELS...HEY...ANOTHER TWO-CAMP SOLUTION. THIS TIME THE GFS/UKMET
ARE IN A MORE NORTHERLY CAMP WITH THE EJECTING SOUTHERN UPPER LOW
(EASTERN OHIO TUESDAY EVENING)...WHICH WOULD RESULT IN WETTER WX
HERE. THE OPERATIONAL GFS OFFERS THE MOST DIRE SOLUTION.
MEANWHILE...THE NAM...ECMWF...AND GEM ARE MORE SOUTHERLY (TN/NC/VA
BORDER AREA) AND DRIER. HPC RECOMMENDS HEDGING OUR BETS WITH A
GFS/ECMWF COMPROMISE...WHICH SEEMS A REASONABLE APPROACH UNTIL
THINGS GETS FURTHER NAILED DOWN.
TONIGHT/MONDAY...MODELS HAVE TRENDED COLDER TONIGHT...WITH 850MB
TEMPS OF -9C LINGERING TO AROUND MIDNIGHT (DELTA T/S 15-16). WILL
ADJUST POPS TONIGHT HIGHER...WITH A SMALL AREA OF LIKELY POPS IN
BOTH PENINSULAS IN NW/NNW SNOWBELTS. AM A LITTLE CONCERNED WE COULD
MANAGE SOME SNEAKY 1-2 INCH ACCUMS...ESPECIALLY GIVEN THE SOLID
SUPERIOR CONNECTION INTO NW LOWER. BUT WE WON/T HAVE MUCH TIME FOR
CONVECTION TO RECOVER/REORGANIZE AFTER DIURNAL DISRUPTIONS...BEFORE
THE 850MB THERMAL TROF LIFTS OUT TO THE NE OVERNIGHT. BY 12Z...850MB
TEMPS WILL BE DOWN TO THE -4/-5C RANGE...AND THERE SHOULDN/T BE ANY
PRECIP LEFT FOR MONDAY. SKIES WILL TEND TO CLEAR MONDAY...WITH HIGH
PRESSURE OVERHEAD AND A NARROW WEDGE OF SHARP SUBSIDENCE (850-700MB
RH GOES BELOW 20 PERCENT). SOME MID/HIGH CLOUDS WILL LINGER NEAR
SAGINAW BAY.
MIN TEMPS IN THE 20S TONIGHT...WITH SOME UPPER TEENS POSSIBLE IN
INTERIOR SECTIONS OF NE LOWER MI. MAX TEMPS UPPER 30S TO AROUND 40F.
MONDAY NIGHT/TUESDAY...A NORTHERN STREAM SHORTWAVE WILL MAKE
EASTWARD PROGRESS ACROSS NORTHERN MN MONDAY NIGHT...AND THEN WILL
WASH OUT AS THE LARGER CIRCULATION TO THE SOUTH AND SE TAKES OVER.
BAND OF F-GEN AND ASSOCIATED MID CLOUDS AHEAD OF THIS WAVE WILL
REACH EASTERN UPPER MI BY DAWN TUESDAY...PRODUCING VIRGA AND MAYBE A
FLURRY.
THE BIGGER CONCERN IS THE DEEP LOW TO THE SOUTH. MODEL DIFFS ARE
RELATIVELY MINOR THRU 12Z TUESDAY...WITH RAIN DEFINITELY MOVING INTO
SE LOWER MI...AND NAM/GFS BOTH TRY TO BACK UP PRECIP TOWARD SAGINAW
BAY. WILL MAINTAIN A CHANCE OF RAIN IN THE SE ZONES (ALL PRECIP
LIQUID THERE...WITH 850MB TEMPS 3-4C...AND SURFACE TEMPS IN THE MID
30S. ALL MODELS CONTINUE TO SLOWLY EXPAND PRECIP NORTHWARD AS THE
UPPER LOW LOVES UP THE TN VALLEY AND CENTRAL APPALACHIANS. WILL
BOOST AND EXPAND POPS...WITH LIKELY POPS ALONG/SE OF HTL-APN...AND
CATEGORICAL NEAR TAWAS/STANDISH. THIS WILL ALMOST ALL LIQUID...WITH
ABOVE FREEZING 850MB AND SURFACE TEMPS IN MOST OF THE PRECIP AREA.
HOWEVER...ALONG THE OUTER EDGE OF THE PRECIP SHIELD...850MB TEMPS
WILL DROP SLIGHTLY BELOW ZERO...AND THE SURFACE-BASED WARM LAYER
WILL SHRINK BELOW 1K FEET. WILL MENTION A RAIN/SNOW MIX ALONG THE NW
EDGE (MANISTEE TO CHEBOYGAN).
MIN TEMPS UPPER 20S TO AROUND 30 IN MOST PLACES...EXCEPT LOW/MID 30S
FAR SE. MAX TEMPS MID 30S TO LOWER 40S.
REST OF THE FORECAST...FORECAST RAPIDLY TURNS MORE INTERESTING TUE
NIGHT. AS THE SURFACE LOW PASSES BY TO THE EAST...COLD
ADVECTION FROM 850MB ON DOWN WILL RAPIDLY TURN PRECIP FROM RAIN TO
SNOW. PRECIP WILL BE DWINDLING LATE TUE NIGHT AND OUT OF THE PICTURE
COMPLETELY BY MIDDAY WEDNESDAY. WILL INCREASE POPS TUESDAY
NIGHT...INCLUDING ADDING SOME LIKELY POPS IN NE LOWER (RAIN/SNOW MIX
IN THE EVENING...ALL SNOW OVERNIGHT). SNOW POTENTIAL VARIES GREATLY
FROM MODEL TO MODEL...AS THEY DIFFER ON BOTH PRECIP PRODUCTION (GFS
IS QUITE WET...UP TO AN INCH OF QPF TUE NIGHT IN NE LOWER)...AND ON
HOW QUICKLY TO TURN PRECIP TO SNOW. CERTAINLY POTENTIAL IS THERE FOR
MODERATE (ADVISORY-LEVEL) ACCUMS...PERHAPS EVEN MORE IN A WORST-CASE
SCENARIO.
JZ
&&
.MARINE.../ISSUED AT 1126 AM/
AT 11 AM...ADDED THE STRAITS TO THE SCA. OTHERWISE ALL OTHER SCA
HEADLINES REMAIN AS IS FROM 405 AM ISSUANCE.
COLD FRONT HAS EXITED THE WATERS SURROUDNING NRN MI. NW- NNW
GUSTS WILL CONTINUE 25-30KT IN MOST PLACES WELL.
HALBLAUB
WINDS WILL DIMINISH LATE TONIGHT INTO MONDAY AS HIGH PRESSURE
BRIEFLY SETTLES INTO THE LAKES REGION.
JZ
&&
.AVIATION.../ISSUED AT 642 AM/...VALID FOR 12Z TAFS
LOW PRESSURE NE OF THE SAULT WILL CONTINUE TO MOVE NE AWAY FROM THE
REGION. THE ASSOCIATED COLD FRONT WAS MOVING OFF THE LAKE HURON
COAST. RAIN WILL DIMINISH TODAY...THOUGH SOME LAKE EFFECT SHRA/SHSN
COULD IMPACT THE TAF SITES NEAR LAKE MI (ESPECIALLY TVC) LATE THIS
AFTERNOON THRU THIS EVENING. CIGS WILL SLOWLY IMPROVE AS THE DAY
PROCEEDS...AND WILL BE LARGELY MVFR...THOUGH COULD DRIP IFR AT TIMES
EARLY THIS MORNING. CIGS WILL BECOME MAINLY VFR BY LATE TONIGHT...AS
HIGH PRESSURE BRIEFLY BUILDS IN.
JZ
&&
.CLIMATE.../ISSUED AT 1126 AM/
RECORDS: ALL LONG-TERM CLIMATE SITES EXCEPT SSM SET/TIED THE WARMEST
LOW TEMPS ON RECORD YESTERDAY.
APN 45F (OLD RECORD 41 IN 1948)
GLR 46F (OLD RECORD 39 IN 2009)
HTL 48F (OLD RECORD 43 IN 2006)
TVC 50F (TIED OLD RECORD 50 IN 1915)
HALBLAUB
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 5 AM EST MONDAY FOR LHZ345-347-348.
LM...SMALL CRAFT ADVISORY UNTIL 5 AM EST MONDAY FOR LMZ323-342-
344>346.
LS...SMALL CRAFT ADVISORY UNTIL 5 AM EST MONDAY FOR LSZ321.
&&
$$
WFO APX
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
346 PM CST SUN NOV 27 2011
.DISCUSSION...
SUMMARY...LARGELY DRY FORECAST WITH ONLY SMALL POPS IN THE
FORECAST FOR THURSDAY AND NEXT SUNDAY. THREE COLD FRONTS MOVE
THROUGH OVER THE NEXT 7 DAYS...MONDAY NIGHT...WEDNESDAY
NIGHT...AND SATURDAY NIGHT. SLIGHTLY ABOVE NORMAL TEMPS ARE
EXPECTED AHEAD OF THESE BOUNDARIES MONDAY...WEDNESDAY AND
SATURDAY. NEAR NORMAL OR SLIGHTLY BELOW NORMALS TEMPS ARE
EXPECTED BEHIND THE FRONTAL PASSAGES ON TUESDAY...
THURSDAY...FRIDAY AND SUNDAY.
TONIGHT AND TOMORROW...TRICKY TEMP FORECAST: STATUS DECK HAS BEEN
VERY SLOW TO CLEAR TODAY AND CONTINUES MOVING TO THE EAST AT JUST
7KTS. WITHIN THE LAST HOUR OR SO...WE`RE FINALLY SEEING SOME
THINNING OF THE DECK IN MN. THIS MIGHT BE A SIGN THAT THE CLEARING
IS A BIT FASTER THAN WHAT`S IN THE FORECAST FOR TONIGHT.
HOWEVER...WE WILL LOSE OUR SUN HERE IN THE NEXT COUPLE HOURS...SO
KEPT THE SLOW CLEARING TREND IN THE FORECAST TONIGHT. MIGHT HAVE
TO WAIT FOR THE RIDGE AXIS TO PASS OVERHEAD...WHICH WOULD MATCH UP
FAIRLY WELL WITH THE 925MB RH OFF THE RUC THIS EVENING. THE CLOUDS
WILL OBVIOUSLY HAVE LARGE IMPACT ON THE TEMPERATURES TONIGHT. KEPT
WEST CENTRAL WI IN THE MID 20S AND EVEN LEFT MOST OF THE METRO IN
THE LOWER TO MID 20S. AREAS THAT GET AT 3-4 HOURS OF CLEAR SKIES
TOMORROW MORNING...WILL LIKELY GET INTO THE TEENS FOR LOWS.
OTHERWISE...THE MERCURY WILL BE HEAD THE OTHER WAY TOMORROW WITH
WARM AIR ADVECTION KICKING IN BETWEEN 06-12Z TONIGHT. SOUTHWEST
WINDS WITH MIXING UP TO 975-925MB OFF THE FORECAST SOUNDINGS WOULD
GIVE US LOW TO MID 40S ALMOST EVERYWHERE TOMORROW. IN
FACT...DOWNSLOPING OFF THE BUFFALO RIDGE IN WESTERN MN SHOULD
YIELD 50S FOR HIGHS. COLD FRONT PASSES THROUGH FROM NW TO SE LATE
TOMORROW AFTERNOON AND TOMORROW EVENING. MIGHT BE A MID DECK OF
CLOUDS WITH THE FRONT BUT NO PRECIPITATION IS EXPECTED.
TUESDAY THROUGH THURSDAY...-4 TO -6 C AT 850MB INDICATING A COOL
DOWN FOR TUESDAY BEHIND THE FRONT BUT CERTAINLY NOTHING OUT OF THE
ORDINARY. THE COOL DOWN WILL BE BRIEF WITH 1000-500MB THICKNESS
ALREADY CLIMBING BETWEEN 540M-546M EARLY WEDNESDAY. ANOTHER FRONT
MOVES THROUGH WEDNESDAY NIGHT AND WITH THIS BOUNDARY THERE MIGHT
BE JUST ENOUGH FORCING AND MOISTURE TO SHAKE OUT A FEW SNOW FLAKES
IN THE STRATO CUMULUS IN THE WAKE OF THE FRONT ON THURSDAY. BOTH
THE 27.12Z GFS/ECMWF HAVE A FEW TENTHS OF SNOW ACCUMULATION ACROSS
CENTRAL MN AND WESTERN WI.
EXTENDED...NO MAJOR SYSTEMS OUT ON THE HORIZON. WOULDN`T BE
SURPRISED IF WE END UP WITH A LITTLE PRECIP NEXT SUNDAY BASED ON
THE PATTERN INDICATED BY THE ECMWF AND TO A LESSER DEGREE THE
LATEST GFS ENSEMBLE. CPC IS FORECASTING BELOW NORMAL TEMPERATURES
FOR MUCH OF THE COUNTRY IN THE 6-14 DAY OUTLOOKS. ALTHOUGH THE
SIGNAL ISN`T QUITE AS STRONG IN MN/WI...IT FINALLY APPEARS WE
SHOULD GET INTO A MORE WINTER-LIKE AIR MASS AFTER NEXT WEEKEND.
&&
.AVIATION.../18Z TAF ISSUANCE/
BACK EDGE OF MVFR CIGS MVG EAST PAINFULLY SLOW...LESS THAN 10 KTS.
PIREPS SHOWING CLOUDS 1500 TO 2000 FEET THICK. SLOWED DOWN CLEARING
FROM PRESENT TAFS A BIT..TYING CLEARING TREND TO THE SURFACE RIDGE
LINE. SEE SPECIFIC TAFS FOR TIMING. SURFACE PRESSURE GRADIENT
REMAINS FAIRLY TIGHT ...SHUD SEE GUSTS AROUND 20 KTS MSP AND WI TAFS
UNTIL AROUND 21Z. WINDS BECOMING LIGHT AS RIDGE MOVES ACROSS AND
THEN S TO SW FOR MONDAY AHEAD OF CDFNT.
KMSP...CIGS 2500 TO 3000 FEET THRU ABOUT 01Z AND THEN CLOUDS
BECOMING SCT AS SURFACE RIDGE MOVES INTO AREA. WINDS REMAINING NW
INTO THE EARLY EVENING WITH GUSTS 20 KTS UNTIL 21Z.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
BAP/CLF
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
303 PM CST SUN NOV 27 2011
.DISCUSSION...
Short Term (Tonight-Tuesday Night)...
A subtle northwest wind shift has helped dislodge the clearing line
which has been anchored over ern KS and ern NE since yesterday
afternoon. Eastward advancement has picked up the last several
hours, and should slow somewhat this evening, but ultimately clear
the eastern CWA before daybreak.
As winds diminish tonight, expect we`ll end up with one of the
coldest nights to date over the western half of the CWA where upper
teens are possible in the NW sheltered regions and the low-mid 20s
elsewhere.
It should be noted that some extremely dry boundary layer air exists
over central Kansas into Nebraska with dewpoints below zero in some
areas. This airmass will spread eastward tomorrow, and have manually
adjusted gridded dwpt/RH fields to account for anomalously low
readings during the afternoon. Light to calm winds should keep fire
danger to a minimum, especially after the rainfall on Friday.
Otherwise, a rather chilly day in store with limited mixing as an
elongated surface ridge axis shifts overhead.
Models continue to indicate a low level density surge pushing
southeast across the area early Tuesday morning, with a very strong
isobar packing in its wake, accentuated by strong cyclogenesis over
the southeast states. For lack of a better description, this
secondary cold front, trailed by a 1035mb surface high, will usher
in another reinforcing shot of cold air and strong winds for
Tuesday. Much like Saturday, it will feel pretty brutal with
temperatures struggling to reach 40 degrees with wind gusts
frequently reaching 30-35 mph.
Bookbinder
Medium Range (Wednesday through Sunday)...
The main forecast concern in the extended time frame will be the
chance for precipitation and precipitation type on Saturday night.
Wednesday-Friday...models in good agreement through the period.
Wednesday, a surface ridge of high pressure will dominate the region
keeping conditions dry. On Thursday, an upper level low will be
digging southward along the west coast. In response, upstream upper
level ridging will exist over the Southern Plains and into the
Midwest keeping conditions dry as a weak cold front drops through
the forecast area. On Friday, the upper level ridge flattens out as
a upper level trough drops down from the Northern Plains into the
Upper Midwest. Precipitation with this system however, will remain
north of the forecast area.
Saturday-Sunday...Model solutions begin to differ as to the
progression of the west coast trough. The 00Z EC has flip-flopped
with the 12Z GFS becoming the more progressive solution. On
Saturday, the EC takes a closed upper low over the extreme
southwestern CONUS and opens it into a upper trough as it moves out
into the central and southern Rockies by Saturday night. WAA will
draw moisture northward into the forecast area out ahead of a
associated surface cold front. The EC develops showers ahead of the
front with the chance for a mix of rain and snow showers behind the
front. The EC then moves this system east of the forecast area with
high pressure building in behind it on Sunday. The GFS is slower and
further south with the upper level low as it has it digging further
south than the EC into the Baja on Saturday. By Sunday, the closed
low moves into the southwestern CONUS with precipitation remaining
well south and west of the forecast area. To account for the EC
solution have chance pops for Saturday night across the forecast
area changing to a rain/snow mix behind the cold front.
73
&&
.AVIATION...
Borderline MVFR/VFR stratus deck hasn`t moved 5 miles from when I
arrived on shift at 4PM yesterday, and when I left at midnight this
morning. 900-875mb layered RH field in the RUC continues to have the
best handle on this deck, with a gradual expected improvement
between 21-23Z as a subtle 20 degree backing of the wind upstream
across ern Nebraska should result in a slight eastward nudge prior
to sunset.
Otherwise, northwest winds were beginning to lose their gusty
character and will slowly diminish toward sunset, and then rapidly
abate to a light northwest winds at less than 5 knots overnight into
the day Monday with clear skies.
Bookbinder
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1119 AM CST SUN NOV 27 2011
...UPDATED AVIATION DISCUSSION...
.DISCUSSION...
Main challenges for the next few days will be temperatures with an
upper pattern that remains fairly complex across the CONUS.
Today - Tonight:
Temperatures today will likely be slow to recover from their minimal
diurnal range due to cloud cover from moisture trapped underneath a
slow moving upper wave. Low to mid level stratus should hang on
across the area through the mid to late morning hours and then
begin to shift east with the axis of the upper wave, allowing
stronger subsidence and drier air can move in and help to clear
things out. Couple the slower retreat of cloud cover with continued
northerly/northwesterly winds advecting slightly cooler air and
temperatures today look to be stuck in the lower 40s/near 40 for most
areas.
For tonight, skies are expected to clear out with a weak surface
ridge nosing into northwestern Missouri. With dewpoints likely to
fall into the teens overnight, decent radiational cooling should
occur and parts of far northwestern Missouri should be able to fall
into the mid to upper teens. Elsewhere across the forecast area,
winds that don`t completely go calm may keep the boundary layer
mixed enough to keep lows in the low to mid 20s.
Monday - Tuesday:
The upper low will continue to spin to our south and east as another
wave begins to move southeast out of the northern Rockies and Plains
Monday evening/night. With this wave moving through the upper ridge
it leads to a brief raising of thicknesses and heights across the
area. This should allow for temperatures to warm back to more
seasonal readings, especially across the western forecast area. High
temperatures will range from the upper 40s across our west to the
lower 40s in our east as result. This secondary wave will send a
reinforcing shot of cooler air into the region. Fortunately the
airmasses associated with these recent waves have been of a maritime
origin and as a result we really only cool back down into the
lower 40s for Tuesday.
Wednesday - Saturday:
Another wave will move overtop the eastern Pacific upper ridge
Wednesday and Thursday. Models are actually somewhat consistent in
breaking this wave apart and sending the northern portion across the
Great Lakes and pinching off the southern portion into the
Southwestern CONUS. This pretty much leaves our area dry, although
we may see increased cloud cover as there is fair amount of
vorticity that remains between the two main waves. Strong maritime
high pressure reinforces the airmass already in place and as a
result we continue to see a good likelihood of below normal
temperatures through the end of the week. By Saturday however, that
high pressure should have moved to our southeast with winds
returning to southerly/southwesterly direction. This should result
in another modest warm with temperatures returning to near seasonal
levels by Saturday afternoon.
CDB
&&
.AVIATION...
Borderline MVFR/VFR stratus deck hasn`t moved 5 miles from when I
arrived on shift at 4PM yesterday, and when I left at midnight this
morning. 900-875mb layered RH field in the RUC continues to have the
best handle on this deck, with a gradual expected improvement
between 21-23Z as a subtle 20 degree backing of the wind upstream
across ern Nebraska should result in a slight eastward nudge prior
to sunset.
Otherwise, northwest winds were beginning to lose their gusty
character and will slowly diminish toward sunset, and then rapidly
abate to a light northwest winds at less than 5 knots overnight into
the day Monday with clear skies.
Bookbinder
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS BUFFALO NY
541 PM EST SUN NOV 27 2011
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL MOVE INTO THE REGION TONIGHT WITH A
PERIOD OF RAIN. THE RAIN WILL LINGER INTO MONDAY MORNING BEFORE
TAPERING TO WIDELY SCATTERED LIGHT SHOWERS BY AFTERNOON AS THE FRONT
WEAKENS IN PLACE. AN AREA OF LOW PRESSURE WILL THEN LIFT ACROSS THE
LOWER LAKES TUESDAY AND TUESDAY NIGHT WITH MORE RAIN...WHICH MAY END
AS A LITTLE WET SNOW ON WEDNESDAY AS COOLER AIR FILTERS INTO THE
REGION. DRY WEATHER WILL RETURN ON THURSDAY BEFORE COLDER AIR
ARRIVES FRIDAY INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH MONDAY/...
REGIONAL RADAR IMAGERY THIS AFTERNOON SHOWS AN INITIAL BATCH OF
SHOWERS LIFTING ACROSS WESTERN NEW YORK WITH A FEW SPRINKLES ALSO
CROSSING THE EASTERN LAKE ONTARIO REGION. THIS FIRST BATCH OF RAIN
WILL BE VERY LIGHT...AND THE HIGH RESOLUTION HRRR MODEL AND RADAR
TRENDS CONTINUE TO SUGGEST THERE WILL BE A RELATIVE LULL IN SHOWER
ACTIVITY THIS EVENING BETWEEN THIS INITIAL BATCH AND A MORE SOLID
AREA OF RAIN FORECAST TO DEVELOP BY MID TO LATE EVENING ACROSS
WESTERN NEW YORK. TEMPERATURES HAVE SOARED THIS AFTERNOON IN
RESPONSE TO DEEP SOUTHERLY FLOW...WITH UPPER 50S INLAND AND LOWER
60S ON THE LAKE PLAINS DUE TO ADDED COMPRESSIONAL WARMING FROM
DOWNSLOPE FLOW. TEMPS WILL ONLY SLOWLY PULL BACK THIS EVENING AS WE
REMAIN ON THE WARM SIDE OF THE FRONTAL BOUNDARY.
FOR TONIGHT...A COMPLEX TROUGH OVER THE MID SECTION OF THE NATION
WILL SPLIT OVERNIGHT...WITH NORTHERN STREAM ENERGY ACCELERATING EAST
ACROSS QUEBEC...WHILE THE SOUTHERN STREAM ENERGY IS LEFT BEHIND TO
EVOLVE INTO A CLOSED LOW OVER THE LOWER MISSISSIPPI VALLEY. AN
ASSOCIATED COLD FRONT WILL ADVANCE SLOWLY EASTWARD INTO THE REGION
OVERNIGHT...THEN STALL AND WASH OUT ON MONDAY AS THE LOW LEVEL FLOW
QUICKLY EVOLVES INTO A COL BETWEEN THE TWO MID LEVEL CLOSED LOWS.
PWAT OF 1-1.25 INCHES IS AVAILABLE ALONG AND AHEAD OF THIS FRONT...
WHICH IS 2-3 STANDARD DEVIATIONS ABOVE AVERAGE FOR LATE NOVEMBER.
MAIN FORCING MECHANISMS WILL BE FRONTOGENESIS AND CONVERGENCE IN THE
800-700MB LAYER ALONG THE ADVANCING FRONT...AND UPPER LEVEL
DIVERGENCE IN THE RIGHT ENTRANCE REGION OF A 140 KNOT UPPER LEVEL
JET.
WITH THE DEEP LAYER FRONTAL ASCENT AND AMPLE SUPPLY OF MOISTURE
WIDESPREAD RAIN ALONG THE FRONTAL BOUNDARY IS A CERTAINTY...THE MAIN
FORECAST CHALLENGE IS THE PLACEMENT AND TIMING WITH A SHARP EASTERN
CUTOFF TO THE STEADIER RAIN. EXPECT THE STEADIER RAIN TO MAKE IT
INTO WESTERN NY DURING THE MID TO LATE EVENING AND THE NORTH COUNTRY
AS WELL BY LATE EVENING...AFTER THAT IT WILL ONLY MAKE VERY SLOW
PROGRESS EASTWARD TOWARDS THE GENESEE VALLEY AND FINGER LAKES. MANY
AREAS IN CENTRAL NY ALONG THE BORDER WITH THE BGM CWA MAY REMAIN DRY
UNTIL LATE TONIGHT. AS FAR AS RAINFALL AMOUNTS GO...EXPECT BASIN
AVERAGE OF A QUARTER TO A THIRD OF AN INCH ACROSS WESTERN NY AND THE
NORTH COUNTRY...WITH MUCH LESS ACROSS THE FINGER LAKES.
MONDAY MORNING EXPECT RAIN TO STILL BE QUITE WIDESPREAD ACROSS MUCH
OF THE REGION AT SUNRISE. THE STEADIER RAIN WILL QUICKLY TAPER OFF
DURING THE MORNING AS FRONTAL CONVERGENCE BREAKS DOWN DUE TO THE
LOSS OF MID LEVEL FLOW WITHIN THE DEVELOPING COL REGION. THERE WILL
BE PLENTY OF LOW CLOUDS AROUND IN THE WEAK NORTHERLY UPSLOPE FLOW
BEHIND THE WASHING OUT FRONTAL BOUNDARY...SO THIS WILL LIKELY ALLOW
LIGHT SHOWERS AND DRIZZLE TO LINGER INTO THE EARLY AFTERNOON. LATER
IN THE DAY EXPECT MUCH OF THE AREA TO BE DRY...ALTHOUGH WITH THE
LINGERING FRONTAL BOUNDARY NEARBY CANNOT RULE OUT A FEW LIGHT
SHOWERS ESPECIALLY FROM THE SOUTHERN TIER INTO THE FINGER LAKES.
WESTERN AND CENTRAL NY WILL BE ON THE COOL SIDE OF THE BOUNDARY BY
MONDAY...AND THAT COMBINED WITH PLENTY OF LOW/THICK CLOUD COVER WILL
BRING MUCH COOLER TEMPS WITH THE NORTHERN HALF OF THE AREA LIKELY
NOT MAKING IT OUT OF THE UPPER 40S...WITH SOME LOWER 50S NEAR THE
PENNSYLVANIA STATE LINE AND IN CENTRAL NY.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
BY MONDAY EVENING...A DEVELOPING AREA OF LOW PRESSURE ASSOCIATED
WITH A CUT OFF 500 MB LOW WILL BE NEAR KENTUCKY. MEANWHILE...A
STALLED FRONTAL BOUNDARY WILL SIT SOMEWHERE ACROSS WESTERN NEW YORK.
ITS THIS BOUNDARY THAT SHOULD KEY ANY RAIN SHOWERS MONDAY NIGHT. AS THE
LOW LIFTS NORTHWARD...IT WILL FORCE THIS BOUNDARY NORTH AS
WELL...WITH AN INCREASING SOUTHERLY FLOW RESULTING IN WARM AIR
ADVECTION AND LIFT ALONG THIS FRONT. ON MONDAY EVENING EXPECT
SCATTERED SHOWERS ACROSS WESTERN NEW YORK TO ENHANCE AS IT LIFTS
ACROSS LAKE ERIE AND ONTARIO. WHILE MODELS DISAGREE SLIGHTLY ON THE
FRONTAL POSITION...A CONSENSUS BRINGS THE AXIS OF RAIN SHOWERS INTO
SOUTHERN ONTARIO BY DAYBREAK.
ON TUESDAY...THE LOW WILL SLOWLY LIFT INTO OHIO. AS THE SURFACE LOW
LIFTS NORTHWARD...A BROAD AREA OF RAIN WILL LIFT INTO THE REGION
FROM SOUTHWEST TO NORTHEAST. AGAIN...THERE ARE SOME MODEST TIMING
DIFFERENCES...WITH THE GFS ABOUT 6 HOURS FASTER THAN THE
NAM...HOWEVER BOTH MODELS AGREE ON THE GENERAL TREND HERE...SO CAN
JUST SPLIT THE DIFFERENCE. STEADY RAIN SHOULD MOVE IN TUESDAY
AFTERNOON AND EVENING...THEN GRADUALLY EXIT TO THE NORTH LATE
TUESDAY NIGHT.
AS THE LOW LIFTS INTO INTO QUEBEC WEDNESDAY...WINDS WILL SHIFT TO
THE SW AND TEMPERATURES WILL COOL DRAMATICALLY AT BOTH THE SURFACE
AND ALOFT. THIS WILL CAUSE LINGERING RAIN SHOWERS TO MIX WITH SNOW
ON WEDNESDAY. 850 MB TEMPS WILL BE MODESTLY COOL...AT ABOUT -3C. IT
APPEARS FOR MOST...IT WILL BE TOO WARM FOR SNOW SHOWERS TO
ACCUMULATE ON WEDNESDAY. HOWEVER...THE HIGHER TERRAIN OF THE
SOUTHERN TIER BEARS WATCHING. AS THE UPPER LOW PASSES...TEMPERATURES WILL
BE JUST COOL ENOUGH ALOFT FOR SOME MODEST LAKE ENHANCEMENT...AND
SOME UPSLOPING. THIS SAID...IT DOES NOT LOOK LIKE MUCH...PERHAPS A
WET INCH OR TWO ACROSS HIGHER TERRAIN.
WHILE THIS SYSTEM WILL LIKELY CAUSE AN AREA OF HEAVY RAINFALL IN
EXCESS OF TWO INCHES...THIS AREA WILL LIKELY BE TO OUR SOUTH AND
WEST. IT WOULD TAKE A SIGNIFICANT EASTWARD SHIFT IN THE TRACK OF THE
LOW TO CAUSE THIS AXIS TO SHIFT INTO WESTERN NEW YORK...WITH MMEFS
ENSEMBLES SHOWING ONLY A SLIGHT CHANCE OF THIS HAPPENING. IF THERE
WERE TO BE ISSUES...IT WOULD BE IN THE BUFFALO CREEKS. AT THIS
TIME...ABOUT AN INCH OF RAIN IS EXPECTED IN THE NIAGARA
FRONTIER...WITH BETWEEN A HALF INCH AND AN INCH ELSEWHERE. THIS
WOULD NOT BE ENOUGH TO CAUSE FLOODING.
GUSTY NE WINDS WILL DEVELOP ON LAKE ONTARIO AND THE NIAGARA FRONTIER
TUESDAY EVENING. WINDS WILL SHIFT TO THE SOUTHWEST LATE THAT NIGHT
AND WEDNESDAY...WITH BEST WINDS FOCUSING ON LAKE ERIE AND INTO THE
NIAGARA FRONTIER. IN EACH CASE...THE STRONGEST GUSTS LOOK TO BE IN
THE 40 MPH RANGE.
TEMPERATURES WILL CONTINUE TO BE UNSEASONABLY WARM THROUGH TUESDAY
NIGHT. WITH LITTLE DROP IN OVERNIGHT LOWS...ESPECIALLY IN THE
SOUTHERN TIER AND EAST OF LAKE ONTARIO REGIONS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
LINGERING SNOW SHOWERS EAST OF LAKE ONTARIO SHOULD TAPER OFF LATE
WEDNESDAY NIGHT. AFTER THIS...HIGH PRESSURE WILL BUILD INTO THE
REGION THROUGH THURSDAY...BRINGING FAIR WEATHER AND SEASONABLE
TEMPERATURES.
A CLIPPER LOW WILL APPROACH THURSDAY NIGHT...CROSSING THE REGION
FRIDAY. 12Z MODELS HAVE SLOWED A BIT WITH THIS SYSTEM...SO WILL
TREND BACK TIMING ACCORDINGLY. THIS WILL BRING A CHANCE OF SNOW
SHOWERS TO THE REGION FRIDAY...AND ALSO AT THE FIRST MEASURABLE
SNOW OF THE SEASON FOR BUFFALO. 850 MB TEMPS WITH THIS AREA ABOUT
-11C...SO IT SHOULD BE COLD ENOUGH TO PRODUCE LAKE ENHANCED SNOWS
WHERE WINDS ARE FAVORABLE. ITS UNLIKELY THE FAST MOVING WOULD BE
ABLE TO DROP TOO MUCH SNOW GIVEN HOW FAST ITS MOVING.
THE CLIPPER SHOULD EXIT EAST FRIDAY NIGHT...ALLOWING HIGH PRESSURE
TO ONCE AGAIN RIDGE ACROSS THE REGION. SATURDAY SHOULD BE ANOTHER
FAIR AND SEASONABLY COOL DAY.
FOR SUNDAY...THE 12Z GFS/EUROPEAN DIFFER QUITE A BIT. THE GFS DIGS A
TROF INTO THE NORTHEAST...WHICH WOULD BE FAVORABLE FOR SNOW
SHOWERS...WHILE THE EUROPEAN CONTOURS TO KEEP AN UPPER LEVEL RIDGE
ACROSS THE REGION. FOR NOW...LEAN SLIGHTLY TOWARD THE EUROPEAN...AND
KEEP ONLY SLIGHT CHANCE POPS IN FOR SUNDAY.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
THE FIRST BATCH OF SHOWERS IS SPREADING INTO WESTERN NY THIS
AFTERNOON. CIGS/VSBY WILL REMAIN VFR IN MOST LOCATIONS WITH
THIS...ALTHOUGH SOME MVFR WILL BE FOUND ACROSS THE HIGHER ELEVATIONS
OF THE SOUTHERN TIER INCLUDING KJHW...AND ALSO AT KIAG WITH LESS
DOWNSLOPE FLOW AND MORE FLOW OFF LAKE ERIE THAN NEARBY KBUF. MAY SEE
A BREAK IN THE SHOWERS FOR SEVERAL HOURS DURING THE LATE AFTERNOON
AND EARLY EVENING BEFORE A STEADIER RAIN DEVELOPS MID TO LATE
EVENING. ONCE THIS RAIN ARRIVES EXPECT CIGS TO STEADILY DETERIORATE
WITH MVFR GIVING WAY TO IFR OVERNIGHT AS WINDS SLOWLY VEER WITH THE
APPROACH AND PASSAGE OF A COLD FRONT...AND THE LOW LEVELS FULLY
SATURATE. SHOULD SEE WIDESPREAD IFR LASTING FROM LATER TONIGHT
THROUGH MONDAY MORNING. CIGS WILL MAINLY BE MVFR...ALTHOUGH SOME IFR
CIGS WILL ALSO DEVELOP ACROSS THE WESTERN SOUTHERN TIER AND IN ANY
AREAS OF MODERATE RAIN.
ON MONDAY EXPECT A SLOW IMPROVEMENT BACK TO MVFR BY MIDDAY WITH IFR
CIGS LINGERING ACROSS THE SOUTHERN TIER. SCATTERED LIGHT SHOWERS AND
DRIZZLE WILL CONTINUE THROUGH MIDDAY WITH A STALLED OUT FRONTAL
BOUNDARY NEARBY.
LOW LEVEL WIND SHEAR WILL CONTINUE THROUGH THIS EVENING WITH A 40-50
KNOT LOW LEVEL JET OVERHEAD. THIS QUICKLY BREAKS DOWN LATER THIS
EVENING AND WILL BRING AN END TO THE WIND SHEAR.
OUTLOOK...
TUESDAY...AREAS OF MVFR/IFR WITH SHOWERS LIKELY AT TIMES.
WEDNESDAY...MVFR WITH RAIN/SNOW SHOWERS.
THURSDAY...VFR.
FRIDAY...MVFR WITH A CHANCE OF SNOW SHOWERS.
&&
.MARINE...
MODERATE SOUTHERLY WINDS WILL CONTINUE INTO EARLY THIS EVENING
BEFORE DIMINISHING OVERNIGHT AS THE PRESSURE GRADIENT RELAXES. SMALL
CRAFT ADVISORIES WILL BE MAINTAINED THROUGH THIS EVENING ON LAKE
ERIE. LATER TONIGHT A COLD FRONT WILL MOVE SLOWLY SOUTHEAST ACROSS
THE LOWER LAKES REGION WITH WINDS VEERING WEST AND EVENTUALLY
NORTHWEST BY MONDAY MORNING. A BRIEF PERIOD OF 15 KNOT WEST WINDS
WILL OCCUR ON LAKE ONTARIO FROM LATE TONIGHT INTO MONDAY MORNING BUT
THIS WILL BE SHORT LIVED AND WINDS AND WAVES ARE EXPECTED TO REMAIN
JUST BELOW SMALL CRAFT ADVISORY CRITERIA.
LATER MONDAY INTO TUESDAY WINDS WILL DIMINISH AND EVENTUALLY BECOME
EAST TO NORTHEAST AND INCREASE AS LOW PRESSURE ORGANIZES OVER THE
OHIO VALLEY. NORTHEAST WINDS WILL INCREASE TUESDAY NIGHT ESPECIALLY
ON LAKE ONTARIO WITH SOLID SMALL CRAFT ADVISORY CONDITIONS AND AN
OUTSIDE CHANCE OF GALES. WINDS FLIP AROUND TO THE SOUTHWEST ON
WEDNESDAY AS LOW PRESSURE PULLS INTO THE SAINT LAWRENCE VALLEY WITH
ANOTHER PERIOD OF HIGH END SMALL CRAFT ADVISORY CONDITIONS ON BOTH
LAKES.
&&
.CLIMATE...
THE VERY WARM NOVEMBER CONTINUES WITH MANY AREAS ON THE LAKE
PLAINS CRACKING INTO THE LOWER 60S TODAY ON MILD SOUTHERLY WINDS.
HERE ARE SOME STATS THROUGH NOVEMBER 26TH...
AT BUFFALO...THE AVERAGE TEMPERATURE FOR THE MONTH IS 46.3 DEGREES
WHICH IS 4.7 DEGREES ABOVE AVERAGE. THIS RANKS AS THE 6TH WARMEST
ON RECORD. THERE ARE A FEW MORE WARM DAYS ON THE WAY...AND THIS
MAY ALLOW US TO COME UP A SLOT OR TWO BUT THE WARMEST NOVEMBER IS
OUT OF REACH. THERE HAS YET TO BE MEASURABLE SNOW AT THE BUFFALO
AIRPORT WITH A TRACE ON SEVERAL DAYS THIS MONTH. THE LATEST DATE
OF FIRST MEASURABLE SNOW IS DECEMBER 3RD...WITH 4 PREVIOUS YEARS
SEEING NO MEASURABLE SNOW IN THE MONTH OF NOVEMBER. ONE OF THESE
YEARS WAS JUST TWO YEARS AGO IN 2009 WHEN THE FIRST MEASURABLE
SNOW WAS ON DECEMBER 1ST. THERE IS A CHANCE OF SOME WET SNOW ON
WEDNESDAY BUT THIS MAY NOT MEASURE AS SURFACE TEMPERATURES REMAIN
ABOVE FREEZING.
AT ROCHESTER...THE AVERAGE TEMPERATURE FOR THE MONTH IS 45.5
DEGREES WHICH IS 4.2 DEGREES ABOVE AVERAGE. THIS RANKS AS THE 8TH
WARMEST ON RECORD. THERE ARE A FEW MORE WARM DAYS ON THE
WAY...AND THIS MAY ALLOW US TO COME UP A SLOT OR TWO BUT THE
WARMEST NOVEMBER IS OUT OF REACH. UNLIKE BUFFALO...THE ROCHESTER
AIRPORT RECEIVED ITS FIRST MEASURABLE SNOW ON NOVEMBER 17TH.
IT SHOULD BE NOTED THAT PAST RESEARCH SHOWS NO CORRELATION BETWEEN
A WARM FALL AND THE UPCOMING WINTER.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 9 PM EST THIS EVENING FOR LEZ040-
041.
&&
$$
SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...APFFEL
LONG TERM...APFFEL
AVIATION...HITCHCOCK
MARINE...HITCHCOCK/TJP
CLIMATE...HITCHCOCK
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
407 PM EST SUN NOV 27 2011
.SYNOPSIS...
WEAKENING FRONT AND INCREASING MOISTURE TONIGHT INTO MONDAY...WILL
RESULT IN THICKENING CLOUDS WITH SOME LIGHT SHOWERS OR PATCHY
DRIZZLE. HOWEVER...OUR MAIN BATCH OF RAIN WILL COME FROM A LOW
PRESSURE SYSTEM MOVING THROUGH THE REGION TUESDAY AFTERNOON
THROUGH TUESDAY NIGHT. SOME SHOWERS MAY LINGER INTO WEDNESDAY.
BEHIND THE SYSTEM...TEMPERATURES WILL COOL DOWN TO NEAR NORMAL
LEVELS DURING THE SECOND HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
4 PM UPDATE...TEMPERATURES TOPPED OUT ROUGHLY 13 TO 17 DEGREES
ABOVE NORMAL...BEING HELD BACK FROM GOING FURTHER ONLY BECAUSE OF
THICKENING HIGH CLOUDS. FRONT IS APPROACHING FROM THE WEST BUT
STRUGGLING...WITH MAINLY ONLY VIRGA SO FAR EXCEPT FOR EXTREME
WESTERN PA AND NY. ONE WEAK WAVE TRAVELING THROUGH THE BRISK
SOUTHWEST FLOW WILL MANAGE TO SKIM STEUBEN COUNTY AND SOME OF THE
WESTERN FINGER LAKES WITH LIGHT SHOWERS DURING THE NEXT FEW
HOURS...THE REST OF THE AREA WILL CONTINUE TO SEE THICKENING HIGH
TO MID LEVEL CLOUDS.
A BIT OF A SQUEEZE PLAY TONIGHT INTO MONDAY MORNING...AS FRONT
STALLS OUT IN OUR NORTHWESTERN ZONES WITH LIGHT SHOWERS COMING OUT
OF TOP-DOWN MOISTENING FROM UPPER LEVELS...YET ALSO SHALLOW MARINE
MOISTURE ATTEMPTS TO RIDE IN ON SOUTHERLY LOW LEVEL FLOW. RUC AND
18Z NAM HAVE BACKED OFF SOMEWHAT ON THIS IDEA HOWEVER...WITH LIGHT
SURFACE WIND VEERING TO INCLUDE SOME WESTERLY COMPONENT...WHICH IS
NOT AS FAVORABLE FOR MARINE MOISTURE TO REACH INTO THE AREA. I
HAVE LIMITED PATCHY DRIZZLE MENTION TO SOME OF THE
POCONOS/CATSKILLS REGION SUSCEPTIBLE TO UPSLOPE FLOW...LATER
TONIGHT INTO EARLY MONDAY MORNING. FARTHER NORTHWEST...NOT AS
MUCH LOW LEVEL MOISTURE...YET ENOUGH MOISTURE IN MID/HIGH LEVELS
FOR LIGHT SHOWERS. CLOUDS HANG AROUND THROUGH MONDAY
AFTERNOON...THOUGH WITH ANY SHOWERS DIMINISHING AS WEAK FRONT
BEGINS TO SLOWLY SHIFT NORTHWARD.
WITH AMOUNT OF CLOUD COVER...ESPECIALLY LATE TONIGHT THROUGH
MONDAY...WILL BE STAYING ON WARM SIDE OF GUIDANCE FOR LOWS
TONIGHT...AND COOLER THAN THE MODELS FOR HIGHS MONDAY.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
GOOD MODEL AGREEMENT ON BIG PICTURE FOR UPPER LOW TO PROGRESSIVELY
MOVE THROUGH THE AREA...WITH MODEL CONSENSUS GIVING US OUR MAIN
BATCH OF RAIN LATE TUESDAY INTO TUESDAY NIGHT. WHILE THERE WILL BE
AN ATLANTIC SUBTROPICAL FEED OF MOISTURE...SPEED OF SYSTEM WILL
MINIMIZE ANY THREAT FOR WATER PROBLEMS. AT THIS TIME WE ARE
EXPECTING AREAL AVERAGE OF LESS THAN AN INCH OF RAINFALL.
HOWEVER...SOME MARGINAL INSTABILITY EVIDENT AS NEGATIVELY TILTED
FRONT COMES THROUGH TUESDAY EVENING...TO THE POINT THAT LATER
SHIFTS MAY NEED TO CONSIDER ADDING MENTION OF THUNDER. WITH
DELAYED TIMING OF FRONT...TEMPERATURES LOOK TO GET QUITE WARM ON
TUESDAY.
COLD CORE OF UPPER LOW PASSES DIRECTLY OVERHEAD WEDNESDAY...AND
EXPECTING SCATTERED SHOWERS IN THE WRAP AROUND MOISTURE OF THE
COMMA HEAD. DESPITE STRONG COLD AIR ADVECTION...925-850MB
TEMPERATURES DO NOT SUPPORT SHOWERS CHANGING OVER TO SNOW DURING
THE DAY WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
PERIOD BEGINS WITH VIGOROUS STORM SYSTEM EXITING TO THE EAST, AND
HIGH PRESSURE BUILDING NORTHWARD FROM THE LOWER OHIO VALLEY.
A WEAK LOW PRESSURE CENTER AND ASSOCIATED FRONT WILL MOVE OVER
LAKE ONTARIO EARLY FRIDAY, BRINGING WITH IT A CHANCE FOR A RAIN OR
SNOW SHOWER.
A TROF WILL DIG INTO ONTARIO PROVINCE SATURDAY INTO SUNDAY, WITH
SOME JET ACTIVITY ALONG THE US/CANADIAN BORDER. THIS WILL BRING
A BETTER CHANCE FOR SNOW SHOWERS, ESPECIALLY OVER NY STATE, THIS
WEEKEND.
TEMPERATURES WILL FLUCTUATE BETWEEN SYSTEMS, BUT OVERALL WILL BE
TRENDING BACK TOWARD SEASONABLY COOL READINGS.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
A STALLED FRONTAL SYSTEM STRETCHES FROM LOWER ONTARIO, DOWN LAKE
ERIE. SHOWERS ARE MOVING NORTHEASTWARD ALONG THE FRONT, AND WILL
AFFECT OUR TERMINALS LATER TONIGHT WHEN THE FRONT PUSHES EASTWARD.
THE EASTWARD PUSH OF THE FRONT WILL NOT LAST FOR LONG, AS IT IS
FORECAST TO RETROGRADE WESTWARD OVERNIGHT. HOWEVER SOME DRIZZLE
AND SCATTERED SHOWER ACTIVITY WILL AFFECT THE BGM, SYR, ITH, ELM,
AND RME TERMINALS WELL AFTER DARK. CEILINGS WILL SLOWLY DEGRADE TO
MVFR TERRITORY LATE TONIGHT, BEFORE RISING TO A MOSTLY CLOUDY VFR
DECK TOWARD NOON MONDAY.
AT AVP, THE TERMINAL WILL BE AFFECTED BY A MARINE LAYER OF
MOISTURE WHICH IS FORECAST TO MOVE NORTHWARD THROUGH THE WYOMING
VALLEY. MVFR CEILINGS AND VISIBILITIES WILL ARRIVE BETWEEN 4Z AND
6Z, WITH IFR CONDITIONS SOON TO FOLLOW. A COMBINATION OF FOG AND
DRIZZLE WILL KEEP IFR RESTRICTIONS AT AVP THROUGH MID MORNING.
OUTLOOK...
MON NGT...IFR/MVFR. PERIODS OF RAIN AND FOG.
TUE THRU THU...PATCHY MVFR IN SCT -SHRA. SCT -SHSN AND MVFR/BRIEF
IFR POSSIBLE BEGINNING WED.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...MDP
LONG TERM...DJP
AVIATION...DJP
AREA FORECAST DISCUSSION
NWS BUFFALO NY
332 PM EST SUN NOV 27 2011
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL MOVE INTO THE REGION TONIGHT WITH A
PERIOD OF RAIN. THE RAIN WILL LINGER INTO MONDAY MORNING BEFORE
TAPERING TO WIDELY SCATTERED LIGHT SHOWERS BY AFTERNOON AS THE FRONT
WEAKENS IN PLACE. AN AREA OF LOW PRESSURE WILL THEN LIFT ACROSS THE
LOWER LAKES TUESDAY AND TUESDAY NIGHT WITH MORE RAIN...WHICH MAY END
AS A LITTLE WET SNOW ON WEDNESDAY AS COOLER AIR FILTERS INTO THE
REGION. DRY WEATHER WILL RETURN ON THURSDAY BEFORE COLDER AIR
ARRIVES FRIDAY INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH MONDAY/...
REGIONAL RADAR IMAGERY THIS AFTERNOON SHOWS AN INITIAL BATCH OF
SHOWERS LIFTING ACROSS WESTERN NEW YORK WITH A FEW SPRINKLES ALSO
CROSSING THE EASTERN LAKE ONTARIO REGION. THIS FIRST BATCH OF RAIN
WILL BE VERY LIGHT...AND THE HIGH RESOLUTION HRRR MODEL AND RADAR
TRENDS CONTINUE TO SUGGEST THERE WILL BE A RELATIVE LULL IN SHOWER
ACTIVITY THIS EVENING BETWEEN THIS INITIAL BATCH AND A MORE SOLID
AREA OF RAIN FORECAST TO DEVELOP BY MID TO LATE EVENING ACROSS
WESTERN NEW YORK. TEMPERATURES HAVE SOARED THIS AFTERNOON IN
RESPONSE TO DEEP SOUTHERLY FLOW...WITH UPPER 50S INLAND AND LOWER
60S ON THE LAKE PLAINS DUE TO ADDED COMPRESSIONAL WARMING FROM
DOWNSLOPE FLOW. TEMPS WILL ONLY SLOWLY PULL BACK THIS EVENING AS WE
REMAIN ON THE WARM SIDE OF THE FRONTAL BOUNDARY.
FOR TONIGHT...A COMPLEX TROUGH OVER THE MID SECTION OF THE NATION
WILL SPLIT OVERNIGHT...WITH NORTHERN STREAM ENERGY ACCELERATING EAST
ACROSS QUEBEC...WHILE THE SOUTHERN STREAM ENERGY IS LEFT BEHIND TO
EVOLVE INTO A CLOSED LOW OVER THE LOWER MISSISSIPPI VALLEY. AN
ASSOCIATED COLD FRONT WILL ADVANCE SLOWLY EASTWARD INTO THE REGION
OVERNIGHT...THEN STALL AND WASH OUT ON MONDAY AS THE LOW LEVEL FLOW
QUICKLY EVOLVES INTO A COL BETWEEN THE TWO MID LEVEL CLOSED LOWS.
PWAT OF 1-1.25 INCHES IS AVAILABLE ALONG AND AHEAD OF THIS FRONT...
WHICH IS 2-3 STANDARD DEVIATIONS ABOVE AVERAGE FOR LATE NOVEMBER.
MAIN FORCING MECHANISMS WILL BE FRONTOGENESIS AND CONVERGENCE IN THE
800-700MB LAYER ALONG THE ADVANCING FRONT...AND UPPER LEVEL
DIVERGENCE IN THE RIGHT ENTRANCE REGION OF A 140 KNOT UPPER LEVEL
JET.
WITH THE DEEP LAYER FRONTAL ASCENT AND AMPLE SUPPLY OF MOISTURE
WIDESPREAD RAIN ALONG THE FRONTAL BOUNDARY IS A CERTAINTY...THE MAIN
FORECAST CHALLENGE IS THE PLACEMENT AND TIMING WITH A SHARP EASTERN
CUTOFF TO THE STEADIER RAIN. EXPECT THE STEADIER RAIN TO MAKE IT
INTO WESTERN NY DURING THE MID TO LATE EVENING AND THE NORTH COUNTRY
AS WELL BY LATE EVENING...AFTER THAT IT WILL ONLY MAKE VERY SLOW
PROGRESS EASTWARD TOWARDS THE GENESEE VALLEY AND FINGER LAKES. MANY
AREAS IN CENTRAL NY ALONG THE BORDER WITH THE BGM CWA MAY REMAIN DRY
UNTIL LATE TONIGHT. AS FAR AS RAINFALL AMOUNTS GO...EXPECT BASIN
AVERAGE OF A QUARTER TO A THIRD OF AN INCH ACROSS WESTERN NY AND THE
NORTH COUNTRY...WITH MUCH LESS ACROSS THE FINGER LAKES.
MONDAY MORNING EXPECT RAIN TO STILL BE QUITE WIDESPREAD ACROSS MUCH
OF THE REGION AT SUNRISE. THE STEADIER RAIN WILL QUICKLY TAPER OFF
DURING THE MORNING AS FRONTAL CONVERGENCE BREAKS DOWN DUE TO THE
LOSS OF MID LEVEL FLOW WITHIN THE DEVELOPING COL REGION. THERE WILL
BE PLENTY OF LOW CLOUDS AROUND IN THE WEAK NORTHERLY UPSLOPE FLOW
BEHIND THE WASHING OUT FRONTAL BOUNDARY...SO THIS WILL LIKELY ALLOW
LIGHT SHOWERS AND DRIZZLE TO LINGER INTO THE EARLY AFTERNOON. LATER
IN THE DAY EXPECT MUCH OF THE AREA TO BE DRY...ALTHOUGH WITH THE
LINGERING FRONTAL BOUNDARY NEARBY CANNOT RULE OUT A FEW LIGHT
SHOWERS ESPECIALLY FROM THE SOUTHERN TIER INTO THE FINGER LAKES.
WESTERN AND CENTRAL NY WILL BE ON THE COOL SIDE OF THE BOUNDARY BY
MONDAY...AND THAT COMBINED WITH PLENTY OF LOW/THICK CLOUD COVER WILL
BRING MUCH COOLER TEMPS WITH THE NORTHERN HALF OF THE AREA LIKELY
NOT MAKING IT OUT OF THE UPPER 40S...WITH SOME LOWER 50S NEAR THE
PENNSYLVANIA STATE LINE AND IN CENTRAL NY.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
BY MONDAY EVENING...A DEVELOPING AREA OF LOW PRESSURE ASSOCIATED
WITH A CUT OFF 500 MB LOW WILL BE NEAR KENTUCKY. MEANWHILE...A
STALLED FRONTAL BOUNDARY WILL SIT SOMEWHERE ACROSS WESTERN NEW YORK.
ITS THIS BOUNDARY THAT SHOULD KEY ANY RAIN SHOWERS MONDAY NIGHT. AS THE
LOW LIFTS NORTHWARD...IT WILL FORCE THIS BOUNDARY NORTH AS
WELL...WITH AN INCREASING SOUTHERLY FLOW RESULTING IN WARM AIR
ADVECTION AND LIFT ALONG THIS FRONT. ON MONDAY EVENING EXPECT
SCATTERED SHOWERS ACROSS WESTERN NEW YORK TO ENHANCE AS IT LIFTS
ACROSS LAKE ERIE AND ONTARIO. WHILE MODELS DISAGREE SLIGHTLY ON THE
FRONTAL POSITION...A CONSENSUS BRINGS THE AXIS OF RAIN SHOWERS INTO
SOUTHERN ONTARIO BY DAYBREAK.
ON TUESDAY...THE LOW WILL SLOWLY LIFT INTO OHIO. AS THE SURFACE LOW
LIFTS NORTHWARD...A BROAD AREA OF RAIN WILL LIFT INTO THE REGION
FROM SOUTHWEST TO NORTHEAST. AGAIN...THERE ARE SOME MODEST TIMING
DIFFERENCES...WITH THE GFS ABOUT 6 HOURS FASTER THAN THE
NAM...HOWEVER BOTH MODELS AGREE ON THE GENERAL TREND HERE...SO CAN
JUST SPLIT THE DIFFERENCE. STEADY RAIN SHOULD MOVE IN TUESDAY
AFTERNOON AND EVENING...THEN GRADUALLY EXIT TO THE NORTH LATE
TUESDAY NIGHT.
AS THE LOW LIFTS INTO INTO QUEBEC WEDNESDAY...WINDS WILL SHIFT TO
THE SW AND TEMPERATURES WILL COOL DRAMATICALLY AT BOTH THE SURFACE
AND ALOFT. THIS WILL CAUSE LINGERING RAIN SHOWERS TO MIX WITH SNOW
ON WEDNESDAY. 850 MB TEMPS WILL BE MODESTLY COOL...AT ABOUT -3C. IT
APPEARS FOR MOST...IT WILL BE TOO WARM FOR SNOW SHOWERS TO
ACCUMULATE ON WEDNESDAY. HOWEVER...THE HIGHER TERRAIN OF THE
SOUTHERN TIER BEARS WATCHING. AS THE UPPER LOW PASSES...TEMPERATURES WILL
BE JUST COOL ENOUGH ALOFT FOR SOME MODEST LAKE ENHANCEMENT...AND
SOME UPSLOPING. THIS SAID...IT DOES NOT LOOK LIKE MUCH...PERHAPS A
WET INCH OR TWO ACROSS HIGHER TERRAIN.
WHILE THIS SYSTEM WILL LIKELY CAUSE AN AREA OF HEAVY RAINFALL IN
EXCESS OF TWO INCHES...THIS AREA WILL LIKELY BE TO OUR SOUTH AND
WEST. IT WOULD TAKE A SIGNIFICANT EASTWARD SHIFT IN THE TRACK OF THE
LOW TO CAUSE THIS AXIS TO SHIFT INTO WESTERN NEW YORK...WITH MMEFS
ENSEMBLES SHOWING ONLY A SLIGHT CHANCE OF THIS HAPPENING. IF THERE
WERE TO BE ISSUES...IT WOULD BE IN THE BUFFALO CREEKS. AT THIS
TIME...ABOUT AN INCH OF RAIN IS EXPECTED IN THE NIAGARA
FRONTIER...WITH BETWEEN A HALF INCH AND AN INCH ELSEWHERE. THIS
WOULD NOT BE ENOUGH TO CAUSE FLOODING.
GUSTY NE WINDS WILL DEVELOP ON LAKE ONTARIO AND THE NIAGARA FRONTIER
TUESDAY EVENING. WINDS WILL SHIFT TO THE SOUTHWEST LATE THAT NIGHT
AND WEDNESDAY...WITH BEST WINDS FOCUSING ON LAKE ERIE AND INTO THE
NIAGARA FRONTIER. IN EACH CASE...THE STRONGEST GUSTS LOOK TO BE IN
THE 40 MPH RANGE.
TEMPERATURES WILL CONTINUE TO BE UNSEASONABLY WARM THROUGH TUESDAY
NIGHT. WITH LITTLE DROP IN OVERNIGHT LOWS...ESPECIALLY IN THE
SOUTHERN TIER AND EAST OF LAKE ONTARIO REGIONS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
LINGERING SNOW SHOWERS EAST OF LAKE ONTARIO SHOULD TAPER OFF LATE
WEDNESDAY NIGHT. AFTER THIS...HIGH PRESSURE WILL BUILD INTO THE
REGION THROUGH THURSDAY...BRINGING FAIR WEATHER AND SEASONABLE
TEMPERATURES.
A CLIPPER LOW WILL APPROACH THURSDAY NIGHT...CROSSING THE REGION
FRIDAY. 12Z MODELS HAVE SLOWED A BIT WITH THIS SYSTEM...SO WILL
TREND BACK TIMING ACCORDINGLY. THIS WILL BRING A CHANCE OF SNOW
SHOWERS TO THE REGION FRIDAY...AND ALSO AT THE FIRST MEASURABLE
SNOW OF THE SEASON FOR BUFFALO. 850 MB TEMPS WITH THIS AREA ABOUT
-11C...SO IT SHOULD BE COLD ENOUGH TO PRODUCE LAKE ENHANCED SNOWS
WHERE WINDS ARE FAVORABLE. ITS UNLIKELY THE FAST MOVING WOULD BE
ABLE TO DROP TOO MUCH SNOW GIVEN HOW FAST ITS MOVING.
THE CLIPPER SHOULD EXIT EAST FRIDAY NIGHT...ALLOWING HIGH PRESSURE
TO ONCE AGAIN RIDGE ACROSS THE REGION. SATURDAY SHOULD BE ANOTHER
FAIR AND SEASONABLY COOL DAY.
FOR SUNDAY...THE 12Z GFS/EUROPEAN DIFFER QUITE A BIT. THE GFS DIGS A
TROF INTO THE NORTHEAST...WHICH WOULD BE FAVORABLE FOR SNOW
SHOWERS...WHILE THE EUROPEAN CONTOURS TO KEEP AN UPPER LEVEL RIDGE
ACROSS THE REGION. FOR NOW...LEAN SLIGHTLY TOWARD THE EUROPEAN...AND
KEEP ONLY SLIGHT CHANCE POPS IN FOR SUNDAY.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
THE FIRST BATCH OF SHOWERS IS SPREADING INTO WESTERN NY THIS
AFTERNOON. CIGS/VSBY WILL REMAIN VFR IN MOST LOCATIONS WITH
THIS...ALTHOUGH SOME MVFR WILL BE FOUND ACROSS THE HIGHER ELEVATIONS
OF THE SOUTHERN TIER INCLUDING KJHW...AND ALSO AT KIAG WITH LESS
DOWNSLOPE FLOW AND MORE FLOW OFF LAKE ERIE THAN NEARBY KBUF. MAY SEE
A BREAK IN THE SHOWERS FOR SEVERAL HOURS DURING THE LATE AFTERNOON
AND EARLY EVENING BEFORE A STEADIER RAIN DEVELOPS MID TO LATE
EVENING. ONCE THIS RAIN ARRIVES EXPECT CIGS TO STEADILY DETERIORATE
WITH MVFR GIVING WAY TO IFR OVERNIGHT AS WINDS SLOWLY VEER WITH THE
APPROACH AND PASSAGE OF A COLD FRONT...AND THE LOW LEVELS FULLY
SATURATE. SHOULD SEE WIDESPREAD IFR LASTING FROM LATER TONIGHT
THROUGH MONDAY MORNING. CIGS WILL MAINLY BE MVFR...ALTHOUGH SOME IFR
CIGS WILL ALSO DEVELOP ACROSS THE WESTERN SOUTHERN TIER AND IN ANY
AREAS OF MODERATE RAIN.
ON MONDAY EXPECT A SLOW IMPROVEMENT BACK TO MVFR BY MIDDAY WITH IFR
CIGS LINGERING ACROSS THE SOUTHERN TIER. SCATTERED LIGHT SHOWERS AND
DRIZZLE WILL CONTINUE THROUGH MIDDAY WITH A STALLED OUT FRONTAL
BOUNDARY NEARBY.
LOW LEVEL WIND SHEAR WILL CONTINUE THROUGH THIS EVENING WITH A 40-50
KNOT LOW LEVEL JET OVERHEAD. THIS QUICKLY BREAKS DOWN LATER THIS
EVENING AND WILL BRING AN END TO THE WIND SHEAR.
OUTLOOK...
TUESDAY...AREAS OF MVFR/IFR WITH SHOWERS LIKELY AT TIMES.
WEDNESDAY...MVFR WITH RAIN/SNOW SHOWERS.
THURSDAY...VFR.
FRIDAY...MVFR WITH A CHANCE OF SNOW SHOWERS.
&&
.MARINE...
MODERATE SOUTHERLY WINDS WILL CONTINUE INTO EARLY THIS EVENING
BEFORE DIMINISHING OVERNIGHT AS THE PRESSURE GRADIENT RELAXES. SMALL
CRAFT ADVISORIES WILL BE MAINTAINED THROUGH EARLY EVENING ON LAKE
ERIE. LATER TONIGHT A COLD FRONT WILL MOVE SLOWLY SOUTHEAST ACROSS
THE LOWER LAKES REGION WITH WINDS VEERING WEST AND EVENTUALLY
NORTHWEST BY MONDAY MORNING. A BRIEF PERIOD OF 15 KNOT WEST WINDS
WILL OCCUR ON LAKE ONTARIO FROM LATE TONIGHT INTO MONDAY MORNING BUT
THIS WILL BE SHORT LIVED AND WINDS AND WAVES ARE EXPECTED TO REMAIN
JUST BELOW SMALL CRAFT ADVISORY CRITERIA.
LATER MONDAY INTO TUESDAY WINDS WILL DIMINISH AND EVENTUALLY BECOME
EAST TO NORTHEAST AND INCREASE AS LOW PRESSURE ORGANIZES OVER THE
OHIO VALLEY. NORTHEAST WINDS WILL INCREASE TUESDAY NIGHT ESPECIALLY
ON LAKE ONTARIO WITH SOLID SMALL CRAFT ADVISORY CONDITIONS AND AN
OUTSIDE CHANCE OF GALES. WINDS FLIP AROUND TO THE SOUTHWEST ON
WEDNESDAY AS LOW PRESSURE PULLS INTO THE SAINT LAWRENCE VALLEY WITH
ANOTHER PERIOD OF HIGH END SMALL CRAFT ADVISORY CONDITIONS ON BOTH
LAKES.
&&
.CLIMATE...
THE VERY WARM NOVEMBER CONTINUES WITH MANY AREAS ON THE LAKE
PLAINS CRACKING INTO THE LOWER 60S TODAY ON MILD SOUTHERLY WINDS.
HERE ARE SOME STATS THROUGH NOVEMBER 26TH...
AT BUFFALO...THE AVERAGE TEMPERATURE FOR THE MONTH IS 46.3 DEGREES
WHICH IS 4.7 DEGREES ABOVE AVERAGE. THIS RANKS AS THE 6TH WARMEST
ON RECORD. THERE ARE A FEW MORE WARM DAYS ON THE WAY...AND THIS
MAY ALLOW US TO COME UP A SLOT OR TWO BUT THE WARMEST NOVEMBER IS
OUT OF REACH. THERE HAS YET TO BE MEASURABLE SNOW AT THE BUFFALO
AIRPORT WITH A TRACE ON SEVERAL DAYS THIS MONTH. THE LATEST DATE
OF FIRST MEASURABLE SNOW IS DECEMBER 3RD...WITH 4 PREVIOUS YEARS
SEEING NO MEASURABLE SNOW IN THE MONTH OF NOVEMBER. ONE OF THESE
YEARS WAS JUST TWO YEARS AGO IN 2009 WHEN THE FIRST MEASURABLE
SNOW WAS ON DECEMBER 1ST. THERE IS A CHANCE OF SOME WET SNOW ON
WEDNESDAY BUT THIS MAY NOT MEASURE AS SURFACE TEMPERATURES REMAIN
ABOVE FREEZING.
AT ROCHESTER...THE AVERAGE TEMPERATURE FOR THE MONTH IS 45.5
DEGREES WHICH IS 4.2 DEGREES ABOVE AVERAGE. THIS RANKS AS THE 8TH
WARMEST ON RECORD. THERE ARE A FEW MORE WARM DAYS ON THE
WAY...AND THIS MAY ALLOW US TO COME UP A SLOT OR TWO BUT THE
WARMEST NOVEMBER IS OUT OF REACH. UNLIKE BUFFALO...THE ROCHESTER
AIRPORT RECEIVED ITS FIRST MEASURABLE SNOW ON NOVEMBER 17TH.
IT SHOULD BE NOTED THAT PAST RESEARCH SHOWS NO CORRELATION BETWEEN
A WARM FALL AND THE UPCOMING WINTER.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR LEZ040-
041.
&&
$$
SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...APFFEL
LONG TERM...APFFEL
AVIATION...HITCHCOCK
MARINE...HITCHCOCK
CLIMATE...HITCHCOCK
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1255 PM EST SUN NOV 27 2011
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL APPROACH THE REGION ON TODAY WITH
THICKENING CLOUDS AND INCREASING RAIN CHANCES FROM WEST TO EAST.
SHOWERS WILL LAST INTO TONIGHT BEFORE THE FRONT FALLS APART ON
MONDAY WITH JUST A SMALL CHANCE OF A LINGERING SHOWER. AN AREA OF
LOW PRESSURE WILL THEN LIFT ACROSS THE REGION TUESDAY AFTERNOON AND
TUESDAY NIGHT WITH ANOTHER ROUND OF SHOWERS WHICH MAY END AS SOME
WET SNOW ON WEDNESDAY AS SOMEWHAT COLDER AIR ARRIVES.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR IMAGERY EARLY THIS AFTERNOON SHOWS MAINLY LIGHT SHOWERS
ENTERING WESTERN NY. A BREAK IN THE RAIN HAS DEVELOPED IN THE PAST
FEW HOURS ACROSS MUCH OF NORTHEAST OHIO AND CENTRAL LAKE ERIE. THE
EXPERIMENTAL HIGH RESOLUTION 3KM HRRR MODEL SEEMS TO HAVE A GOOD
HANDLE ON THIS...WITH THE INITIAL BATCH OF SHOWERS MOVING THROUGH
THIS AFTERNOON FOLLOWED BY A SEVERAL HOUR BREAK...THEN A STEADIER
RAIN MOVING IN AGAIN BY MID EVENING. WILL CONTINUE TO MONITOR
UPSTREAM RADAR TRENDS...AND IF THIS APPEARS TO BE THE CASE WILL
ATTEMPT TO BUILD THIS TIMING INTO THE NEXT GRID UPDATE.
THIS FRONT IS SLOW MOVING AND WILL CONTINUE TO SLOW DOWN...SO
CENTRAL NY MAY REMAIN DRY FOR MOST IF NOT THE ENTIRE DAY WITH A
RATHER SHARP EASTERN GRADIENT IN PRECIP CHANCES.
850MB TEMPS OF AROUND +9C AND ONGOING DEEP SOUTHERLY FLOW WILL BRING
ANOTHER DAY OF WELL ABOVE AVERAGE TEMPS WITH SOUTHERLY DOWNSLOPE
FLOW BOOSTING THE LAKE PLAINS TO NEAR 60 ONCE AGAIN...WITH LOW 60S
FROM ROCHESTER OVER TOWARD SYRACUSE. FAR WESTERN NY WILL SEE TEMPS
DROP BACK A FEW DEGREES THIS AFTERNOON AS THE STEADIER RAIN MOVE IN.
HIGHER TERRAIN WILL REMAIN IN THE MID TO UPPER 50S WITHOUT THE
BENEFIT OF DOWNSLOPE COMPRESSIONAL WARMING.
EXPECT THE FRONT TO LOSE ALMOST ALL EASTWARD MOTION TONIGHT AND THE
PRECIP WILL WEAKEN SUBSTANTIALLY AS THE UPPER TROUGH LIFTS
NORTHWARD. TEMPS WILL STILL BE WELL ABOVE NORMAL FOR THE NIGHT WITH
LOWS IN THE MID 40S ACROSS THE WEST AND TO NEAR 50 FOR THE EASTERN
LAKE ONTARIO REGION.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
00Z MODELS CONTINUING TO COME INTO BETTER AGREEMENT TO THE OVERALL
SYNOPTIC PATTERN DURING THIS PORTION OF THE FORECAST...LEADING TO
INCREASED FORECASTER CONFIDENCE.
WEAK FRONTAL BOUNDARY WILL BE DROPPING DOWN ACROSS THE SAINT
LAWRENCE VALLEY AND FAR WESTERN NEW YORK AT THE START OF THE PERIOD.
THIS BOUNDARY LOOKS TO EVENTUALLY WASH OUT...AS HIGH PRESSURE
REMAINS ANCHORED OFF THE ATLANTIC COAST AND A CUTOFF LOW DEVELOPS
OVER THE SOUTHEAST STATES...RESULTING IN HEIGHT RISES ACROSS THE
NORTHEAST. WE THINK THAT THERE WILL BE ENOUGH MOISTURE ALONG THE
FRONTAL ZONE FOR THE LIKELIHOOD FOR SHOWERS MONDAY MORNING...THEN
TRENDING TOWARD A DRIER FORECAST AS WE GET INTO THE AFTERNOON AND
EVENING. TEMPERATURES WILL BE PROBLEMATIC FOR MONDAY WITH THE
FRONTAL AND PRECIPITATION POTENTIALLY RESULTING IN A LARGE NORTH
TO SOUTH TEMPERATURES VARIATION WITH HIGHS RANGING FROM THE UPPER
40S IN THE NIAGARA FRONTIER...TO NEAR 60 IN THE SOUTHERN TIER.
SUBTLE SHIFTS IN THE FRONT MAY REQUIRE SIGNIFICANT ADJUSTMENTS TO
TEMPERATURES IN THE FUTURE.
THE SOUTHEASTERN CLOSED LOW WILL LIFT NORTHEASTWARD MONDAY NIGHT
AND TUESDAY...EVENTUALLY REACHING CENTRAL NEW YORK BY TUESDAY NIGHT.
STILL SOME SLIGHT TIMING DIFFERENCES EXIST BETWEEN THE GFS AND ECMWF
ON THE TIMING OF THIS SYSTEM...WITH THE ECMWF BEING ABOUT 6 HOURS
SLOWER. MAJORITY OF THE RAIN SHOULD FALL IN THE TUESDAY THROUGH
TUESDAY NIGHT TIME FRAME AS THE LOW APPROACHES. WILL HAVE TO KEEP
ON EYE ON RAINFALL AMOUNTS WITH THIS SYSTEM AS THERE IS SOME
POTENTIAL FOR MODERATE TO HEAVY RAINFALL.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
COOLER AIR WILL BUILD BEHIND THE LOW WEDNESDAY...MARGINALLY COLD
ENOUGH TO SUPPORT SNOW. GIVEN 850 MB TEMPS WILL ONLY BE -2 TO -4C
ON WEDNESDAY...CHANCES FOR MEASURABLE SNOW WILL BE LIMITED.
BY THIS TIME...THERE IS ACTUALLY QUITE GOOD MODEL AGREEMENT...AS THE
12Z GGEM/EUROPEAN/GFS ALL LIFT THE LOW INTO THE CANADIAN MARITIMES.
EXPECT FAIR AND SEASONABLE WEATHER ON THURSDAY.
MODELS ALL BRING A RATHER SHARP BUT PROGRESSIVE UPPER LEVEL TROF
ACROSS THE REGION LATE THURSDAY NIGHT INTO FRIDAY. TEMPERATURES ARE
FAIRLY COLD WITH THIS...SO THIS WILL BRING A CHANCE OF SNOW SHOWERS
BOTH WITH THE UPPER TROF...AND CONSIDERING LAKE ENHANCEMENT. WHILE
THE SPEED OF THE TROF WILL LIMIT THE CHANCES FOR HEAVY
ACCUMULATIONS...THERE IS A CHANCE FOR MEASURABLE SNOW IN WESTERN NEW
YORK WITH THIS SYSTEM.
THE LOW WILL QUICKLY EXIT SATURDAY NIGHT...WITH ANOTHER FAIR BUT
SEASONABLE DAY EXPECTED ON SATURDAY... AS A ZONAL FLOW DEVELOPS.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
THE FIRST BATCH OF SHOWERS IS SPREADING INTO WESTERN NY THIS
AFTERNOON. CIGS/VSBY WILL REMAIN VFR IN MOST LOCATIONS WITH
THIS...ALTHOUGH SOME MVFR WILL BE FOUND ACROSS THE HIGHER ELEVATIONS
OF THE SOUTHERN TIER INCLUDING KJHW...AND ALSO AT KIAG WITH LESS
DOWNSLOPE FLOW AND MORE FLOW OFF LAKE ERIE THAN NEARBY KBUF. MAY SEE
A BREAK IN THE SHOWERS FOR SEVERAL HOURS DURING THE LATE AFTERNOON
AND EARLY EVENING BEFORE A STEADIER RAIN DEVELOPS MID TO LATE
EVENING. ONCE THIS RAIN ARRIVES EXPECT CIGS TO STEADILY DETERIORATE
WITH MVFR GIVING WAY TO IFR OVERNIGHT AS WINDS SLOWLY VEER WITH THE
APPROACH AND PASSAGE OF A COLD FRONT...AND THE LOW LEVELS FULLY
SATURATE. SHOULD SEE WIDESPREAD IFR LASTING FROM LATER TONIGHT
THROUGH MONDAY MORNING. CIGS WILL MAINLY BE MVFR...ALTHOUGH SOME IFR
CIGS WILL ALSO DEVELOP ACROSS THE WESTERN SOUTHERN TIER AND IN ANY
AREAS OF MODERATE RAIN.
ON MONDAY EXPECT A SLOW IMPROVEMENT BACK TO MVFR BY MIDDAY WITH IFR
CIGS LINGERING ACROSS THE SOUTHERN TIER. SCATTERED LIGHT SHOWERS AND
DRIZZLE WILL CONTINUE THROUGH MIDDAY WITH A STALLED OUT FRONTAL
BOUNDARY NEARBY.
LOW LEVEL WIND SHEAR WILL CONTINUE THROUGH THIS EVENING WITH A 40-50
KNOT LOW LEVEL JET OVERHEAD. THIS QUICKLY BREAKS DOWN LATER THIS
EVENING AND WILL BRING AN END TO THE WIND SHEAR.
OUTLOOK...
TUESDAY...AREAS OF MVFR/IFR WITH SHOWERS LIKELY AT TIMES.
WEDNESDAY...MVFR WITH RAIN/SNOW SHOWERS.
THURSDAY...VFR.
FRIDAY...MVFR WITH A CHANCE OF SNOW SHOWERS.
&&
.MARINE...
LIGHT SOUTHERLY WINDS WILL INCREASE AND BECOME SOUTH SOUTHWEST
TODAY IN ADVANCE OF A COLD FRONT PUSHING THROUGH THE CENTRAL GREAT
LAKES. WINDS WILL INCREASE ENOUGH TO BRING SMALL CRAFT ADVISORY
CONDITIONS ON LAKE ERIE STARTING EARLY THIS MORNING AND CONTINUING
THROUGH THE AFTERNOON. AT THE EAST END OF LAKE ONTARIO WINDS WILL
NOT INCREASE SUFFICIENTLY TO WARRANT A SMALL CRAFT ADVISORY.
LATER SUNDAY NIGHT AND MONDAY THE PRESSURE GRADIENT WILL RELAX AS
THE COLD FRONT FALLS APART OVERHEAD.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR LEZ040-
041.
&&
$$
SYNOPSIS...WCH
NEAR TERM...HITCHCOCK/WCH
SHORT TERM...TMA
LONG TERM...APFFEL
AVIATION...HITCHCOCK
MARINE...WCH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
255 PM CST SUN NOV 27 2011
.SHORT TERM...TONIGHT THROUGH WEDNESDAY
255 PM CST SUN NOV 27 2011
MAIN FORECAST CONCERN IS ON CLOUDS/TEMPERATURES TONIGHT INTO MONDAY.
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED TROUGHING OVER BRITISH COLUMBIA...RIDGING FROM SOUTHERN
CALIFORNIA NORTHEASTWARD INTO SOUTHERN MANITOBA...AND TROUGHING FROM
JAMES BAY SOUTHWEST THROUGH WISCONSIN AND DOWN INTO EASTERN TEXAS.
WITH THE FORECAST AREA ON THE WEST SIDE OF THIS LATTER UPPER
TROUGHING...MID TO UPPER LEVEL SUBSIDENCE IS OCCURRING. THIS CAN BE
SEEN ON 12Z SOUNDINGS FROM ABR...MPX AND DVN. ALSO OF NOTE ON THE
MPX AND DVN SOUNDINGS IS A NEAR TO FULLY SATURATED LAYER FROM 910MB
TO AT LEAST 850MB...REPRESENTATIVE OF THE STRATUS DECK IN PLACE AT
THE TIME. LATEST VISIBLE SATELLITE IMAGERY SHOWED THE STRATUS
COVERING THE ENTIRE FORECAST AREA AND EXTENDING WEST TO A
NORTH-SOUTH LINE THROUGH WINDOM MINNESOTA. GOING A LITTLE FARTHER
WEST...A SURFACE RIDGE IS PRESENT ALONG THE DAKOTAS/MINNESOTA
BORDER. NORTHWEST WINDS REMAIN GUSTY AHEAD OF THE RIDGE WITH GUSTS
OF 20-25 KT OVER THE FORECAST AREA. TEMPERATURES HAVE ALSO STRUGGLED
TO RISE MUCH TODAY...DUE TO A COMBINATION OF THE STRATUS LIMITING
DIURNAL HEATING AND 850MB TEMPS OF -9C OBSERVED AT MPX ON ITS 12Z
SOUNDING.
MUCH OF THE SHORT TERM PERIOD LOOKS QUIET FOR THE FORECAST AREA...
THOUGH THERE ARE A FEW FEATURES TO WATCH. FIRST IS THE SOUTHERN END
OF THE CURRENT UPPER TROUGH IN EAST TEXAS. ALL MODELS AGREE ON THE
SOUTHERN END CLOSING OFF INTO AN UPPER LOW OVER THE SOUTHEASTERN
U.S. MONDAY INTO MONDAY NIGHT...WHICH RESULTS IN SURFACE LOW
DEVELOPMENT ON ITS NORTH SIDE OVER KENTUCKY AND TENNESSEE. THE UPPER
AND SURFACE LOWS THEN GET LIFTED NORTHEAST THROUGH THE EASTERN U.S.
FOR TUESDAY INTO WEDNESDAY...IN RESPONSE TO THE CURRENT BRITISH
COLUMBIA TROUGH MOVING THROUGH THE FORECAST AREA ON TUESDAY. AS OF
NOW IT APPEARS ANY DEFORMATION PRECIPITATION ON THE NORTHWEST SIDE
OF THE UPPER AND SURFACE LOWS WILL STAY TO THE SOUTHEAST...THANKS TO
THAT BRITISH COLUMBIA UPPER TROUGH...PERHAPS REACHING AT MOST THE
ROCKFORD ILLINOIS AREA. OTHERWISE...MUCH OF THE REST OF THE TIME THE
FORECAST AREA SHOULD BE DOMINATED BY SUBSIDENCE AND DRY AIR...DUE TO
UPPER RIDGING COMING ACROSS ON MONDAY AND AGAIN TUESDAY NIGHT INTO
WEDNESDAY...RESULTING IN DRY CONDITIONS.
CLOUD COVER FORECAST IS PROBLEMATIC...ESPECIALLY TONIGHT WITH THE
STRATUS STUCK IN PLACE BELOW THE SUBSIDENCE INVERSION. TYPICALLY TO
GET RID OF STRATUS IN THESE CASES...ESPECIALLY THIS TIME OF YEAR
WITH THE VERY LOW SUN ANGLE...THE SURFACE RIDGE NEEDS TO MOVE IN
AND/OR THROUGH. 27.12Z NAM/GFS SEEM TOO AGGRESSIVE BY CLEARING
THINGS OUT BY 21Z IN OUR WESTERN FORECAST AREA TODAY...WHICH IS
ALREADY TOO FAST PER LATEST SATELLITE IMAGERY. FOLLOWED MORE OF AN
IDEA PRESENTED BY THE RUC AND 925MB WIND FORECASTS...WHICH WOULD
SUGGEST CLEARING MAINLY OCCURRING AFTER MIDNIGHT TONIGHT INTO
MID-DAY MONDAY...WORKING FROM NORTHWEST TO SOUTHEAST AS 925MB WINDS
TURN SOUTHWESTERLY. IT IS POSSIBLE GRANT COUNTY STAYS CLOUDY ALL DAY
MONDAY WITH 925MB WINDS STILL FORECAST NEAR CALM OR OUT OF THE
NORTHEAST...SOMETHING THAT WILL HAVE TO BE MONITORED. OTHERWISE...
SHOULD GET A BAND OF MID/HIGH CLOUDS TO COME ACROSS MONDAY NIGHT
INTO TUESDAY WITH THE BRITISH COLUMBIA UPPER TROUGH. MORE HIGH
CLOUDS LOOK TO MOVE THROUGH WEDNESDAY AFTERNOON AS THE UPPER RIDGE
AXIS CROSSES THE FORECAST AREA.
TEMPERATURES ARE ALSO TRICKY. RAISED LOW TEMPERATURES UP FOR MOST
AREAS TONIGHT INTO THE MID TO UPPER 20S...EXCEPT FOR THE FAR WEST
WHERE CLEARING AND LIGHTER WINDS SHOULD ALLOW TEMPS TO TANK INTO THE
UPPER TEENS TO AROUND 20. STILL SHOULD SEE A DECENT AMOUNT OF SUN ON
MONDAY TO ALLOW TEMPS TO CLIMB INTO THE MID 30S TO LOW 40S...AIDED
BY 850MB TEMPS REACHING 4-6C BY LATE AFTERNOON AHEAD OF THE UPPER
TROUGH. LOOK FOR A COOL DOWN ON TUESDAY AS THE UPPER TROUGH
CROSSES...DROPPING 850MB TEMPS DOWN TO -2 TO -4C AND THUS HIGHS INTO
THE LOW TO MID 30S. TUESDAY NIGHT COULD BE QUITE CHILLY WITH A
SURFACE RIDGE CROSSING AND CLEAR SKIES. STAYED WITH A BLEND OF
GUIDANCE THEN. MODERATION IN TEMPERATURES IS EXPECTED AGAIN ON
WEDNESDAY WITH THE UPPER RIDGE COMING IN...BRINGING 850MB TEMPS UP
TO 1-3C.
.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
255 PM CST SUN NOV 27 2011
SIMILAR TO YESTERDAY...MODELS AND GFS ENSEMBLES ARE IN PRETTY GOOD
AGREEMENT THROUGH FRIDAY ON THE UPPER AIR PATTERN...THEN BEGIN TO
DIVERGE ON HOW TO HANDLE THE WEEKEND. FIRST FEATURE OF INTEREST IS A
LONG WAVE TROUGH EXTENDING FROM SASKATCHEWAN INTO CALIFORNIA AT 00Z
THURSDAY. MODELS PROG THIS TROUGH TO SPLIT INTO TWO...WITH THE
NORTHERN PORTION CROSSING THE FORECAST AREA THURSDAY NIGHT. AHEAD OF
THE TROUGH...MODELS HAVE BECOME IN BETTER AGREEMENT ALL SHOWING SOME
LIGHT SNOW COMING THROUGH...THOUGH FOR THE 27.12Z ECMWF IT IS A
CHANGE FROM ITS PREVIOUS RUN WHICH HAD NO SNOW DUE TO DRY LOW
LEVELS. THEREFORE...ONLY HAVE 20 PERCENT CHANCES OF SNOW AT THE
MOMENT. LATER FORECASTS MAY NEED HIGHER CHANCES IF MODELS STAY IN
AGREEMENT. DRY AND COLDER CONDITIONS LOOK ON TAP FOR THURSDAY NIGHT
INTO FRIDAY AS 850MB TEMPS DROP TO -8 TO -10C AND SURFACE HIGH
PRESSURE BUILDS IN. THE WEEKEND FEATURES ISSUES REGARDING HANDLING
SHORTWAVES DROPPING DOWN OFF A BUILDING EASTERN PACIFIC RIDGE...AND
IF THESE SHORTWAVES CAN POSSIBLY PHASE WITH THE SOUTHERN END OF THE
LONG WAVE TROUGH THAT GOT CUT-OFF ON THURSDAY. THE 27.12Z GFS AND
SOME OF ITS ENSEMBLES SAY THE CUT-OFF LOW REMAINS...RESULTING IN A
DRY NORTHWEST FLOW PATTERN FOR THE WEEKEND. THE 27.12Z ECMWF AND
EXTRAPOLATION OF THE 27.12Z UKMET/CANADIAN SUGGEST A PHASING OR AT
LEAST THE UPPER LOW GETTING KICKED NORTHEAST TOWARDS THE FORECAST
AREA. HARD TO SAY WHICH ONE IS RIGHT AT THIS MOMENT...BUT SINCE
VERIFICATION WISE THE ECMWF TENDS TO A LITTLE BETTER AND DOES HAVE
SOME CONSISTENCY FROM ITS PREVIOUS RUN...TEND TO LEAN MORE TOWARDS
THE ECMWF/UKMET/CANADIAN CAMP. UNDER THIS SCENARIO...SATURDAY SHOULD
STILL END UP DRY WITH MODERATION AS RETURN FLOW SETS UP BEHIND
FRIDAYS SURFACE RIDGE. ISENTROPIC LIFT/WARM ADVECTION THEN SET UP
FOR SATURDAY NIGHT ACROSS FAR SOUTHERN AREAS OF THE CWA...AND ACROSS
THE REST OF THE FORECAST AREA ON SUNDAY AS THE UPPER LOW APPROACHES.
PLACED IN 20 PERCENT CHANCES AT THE PRESENT TIME...GIVEN THE
UNCERTAINTY PRESENT WITH THE GFS SCENARIO AND SOME OF THE GFS
ENSEMBLES.
&&
.AVIATION...THIS AFTERNOON THROUGH MONDAY
1130 AM CST SUN NOV 27 2011
MN/IA/WI REMAIN FIRMLY UNDER MVFR STATUS DECK AS OF MID-DAY.
CLOUDS/MOISTURE ARE TRAPPED UNDER/IN AN INVERSION IN THE 900-850MB
LAYER AND ARE 1500-2000FT DEEP...MAKING THE CLOUD DECK RATHER
RESISTANT TO EROSION/MIXING IN PLACE. DISTANCE-SPEED TOOL APPLIED
TO THE WESTERN EDGE OF THE CLOUDS HAS THE CLEARING LINE MOVING
15018KT. THIS TIMING WOULD PUT THE CLEARING TO KRST AROUND 14Z MON
AND KLSE AROUND 18Z MON. SFC RIDGE AXIS MOVES OVER THE FCST AREA
TONIGHT...WITH WINDS ACROSS CENTRAL/NORTHERN MN/NORTHWEST WI
BECOMING SOUTHWEST/WEST LATE TONIGHT AND FOR MON. THIS MAY
ACCELERATE THE CLOUDS/CLEARING EASTWARD...BUT THIS INCREASE OF
SOUTHWEST FLOW DOES NOT SPREAD OVER THE TAF SITES UNTIL MON MORNING.
HAVE USED THE DISTANCE-SPEED TOOL TIMING OF CLEARING THE MVFR STATUS
OUT OF THE TAFS SITES. SFC PRESSURE GRADIENT CONTINUES TO RELAX THIS
AFTERNOON/EVENING WITH RESULTING GRADUAL DECREASE OF SFC WINDS.
ONCE THE CLOUDS CLEAR THE TAF SITES MON...AN EXTENDED PERIOD OF VFR
CONDITIONS EXPECTED MUCH OF THE UPCOMING WORK WEEK.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
255 PM CST SUN NOV 27 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1130 AM CST SUN NOV 27 2011
.SHORT TERM...TODAY THROUGH WEDNESDAY
1030 AM CST SUN NOV 27 2011
IN THE PROCESS OF ISSUING AN UPDATE TO LINGER THE STRATUS DECK THRU
TONIGHT AND INTO MONDAY OVER MUCH OF THE FCST AREA.
STRATUS EXTENDS ALL THE WAY UP INTO CAN EAST OF LK WINNIPEG.
DISTANCE-SPEED TOOL APPLIED TO WEST EDGE OF THE STRATUS FOR THE PAST
20 HRS HAS IT MOVING 150 DEGREES AT 18KTS. MOISTURE IS 1500-2000 FT
DEEP OVER CENTRAL/EASTERN MN PER LAPS SOUNDINGS AND PILOT REPORTS.
MODEL SOUNDINGS SHOW THE MOISTURE UNDER THE 900-850MB INVERSION AS
WELL AS IN THE STABLE INVERSION LAYER. THIS PLUS THE INVERSION AND
DEPTH OF MOISTURE WILL MAKE THE CLOUDS VERY DIFFICULT TO ERODE/MIX
OUT. IT LOOKING LIKE WE WILL HAVE TO WAIT FOR THE CLOUDS TO ADVECT
OUT OF THE AREA TONIGHT/MON. BASED ON SATELLITE TRENDS WITH THE
DISTANCE-SPEED TOOL AND RUC LOW LEVEL MOISTURE FIELDS...CLEARING
EDGE OF THE CLOUDS DOES NOT REACH THE WEST EDGE OF THE FCST AREA
UNTIL 11Z MON. BULK OF OTHER MODELS MIX/ERODE THE TRAPPED LOW LEVEL
MOISTURE OUT OF MN/IA/WESTERN WI RATHER QUICKLY THIS
AFTERNOON/EVENING WHICH APPEARS VERY OPTIMISTIC. WINDS ACROSS
CENTRAL/NORTHERN MN DO BECOME SOUTHWEST LATE TONIGHT...WITH SOME
ACCELERATION OF THE EAST MOVEMENT OF THE CLOUDS EXPECTED NORTH OF
THE FCST AREA LATE TONIGHT AND ON MON. LAST TO SEE THE CLOUDS CLEAR
MON LOOKING TO BE THE SOUTHEAST END OF THE FCST AREA. THUS HAVE
UPDATED FCST GRIDS FOR MORE CLOUDS TONIGHT INTO MON. HAVE ALSO
RAISED LOWS TONIGHT WHERE SKIES EXPECTED TO REMAIN OVERCAST. HOWEVER
CONCERNED THAT MAY NOT HAVE RAISED THESE ENOUGH OVER THE SOUTHEAST
HALF OF THE FCST AREA WHERE CONFIDENCE IS PRETTY HIGH FOR CLOUDY
SKIES THRU THE NIGHT AND TO 15Z MON.
.LONG TERM...WEDNESDAY NIGHT THROUGH SATURDAY NIGHT
236 AM CST SUN NOV 27 2011
FAIRLY QUIET EXTENDED PERIOD WITH TWO SYSTEMS OF NOTE TO KEEP AN
EYE ON. SOME UNCERTAINTY EXISTS WITH A COLD FRONT THAT DROPS DOWN
THROUGH THE REGION ON THURSDAY WITH SOME OF THE PREVIOUS MODELS
SUGGESTING THAT SOME POST-FRONTAL SNOW COULD FORM. THE LATEST
TREND IS TO GO AWAY FROM THIS THOUGH WITH DRIER AIR IN LOW LEVELS
RESTRICTING ANY PRECIPITATION FROM MAKING IT TO THE GROUND. THE
NEXT CHANCES FOR ANY PRECIPITATION WILL BE ON SATURDAY NIGHT AS
ANOTHER COLD FRONT DROPS DOWN INTO THE REGION.
&&
.AVIATION...THIS AFTERNOON THROUGH MONDAY
1130 AM CST SUN NOV 27 2011
MN/IA/WI REMAIN FIRMLY UNDER MVFR STATUS DECK AS OF MID-DAY.
CLOUDS/MOISTURE ARE TRAPPED UNDER/IN AN INVERSION IN THE 900-850MB
LAYER AND ARE 1500-2000FT DEEP...MAKING THE CLOUD DECK RATHER
RESISTANT TO EROSION/MIXING IN PLACE. DISTANCE-SPEED TOOL APPLIED
TO THE WESTERN EDGE OF THE CLOUDS HAS THE CLEARING LINE MOVING
15018KT. THIS TIMING WOULD PUT THE CLEARING TO KRST AROUND 14Z MON
AND KLSE AROUND 18Z MON. SFC RIDGE AXIS MOVES OVER THE FCST AREA
TONIGHT...WITH WINDS ACROSS CENTRAL/NORTHERN MN/NORTHWEST WI
BECOMING SOUTHWEST/WEST LATE TONIGHT AND FOR MON. THIS MAY
ACCELERATE THE CLOUDS/CLEARING EASTWARD...BUT THIS INCREASE OF
SOUTHWEST FLOW DOES NOT SPREAD OVER THE TAF SITES UNTIL MON MORNING.
HAVE USED THE DISTANCE-SPEED TOOL TIMING OF CLEARING THE MVFR STATUS
OUT OF THE TAFS SITES. SFC PRESSURE GRADIENT CONTINUES TO RELAX THIS
AFTERNOON/EVENING WITH RESULTING GRADUAL DECREASE OF SFC WINDS.
ONCE THE CLOUDS CLEAR THE TAF SITES MON...AN EXTENDED PERIOD OF VFR
CONDITIONS EXPECTED MUCH OF THE UPCOMING WORK WEEK.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
236 AM CST SUN NOV 27 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RRS/AJ
LONG TERM....HALBACH
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1030 AM CST SUN NOV 27 2011
.SHORT TERM...TODAY THROUGH WEDNESDAY
1030 AM CST SUN NOV 27 2011
IN THE PROCESS OF ISSUING AN UPDATE TO LINGER THE STRATUS DECK THRU
TONIGHT AND INTO MONDAY OVER MUCH OF THE FCST AREA.
STRATUS EXTENDS ALL THE WAY UP INTO CAN EAST OF LK WINNIPEG.
DISTANCE-SPEED TOOL APPLIED TO WEST EDGE OF THE STRATUS FOR THE PAST
20 HRS HAS IT MOVING 150 DEGREES AT 18KTS. MOISTURE IS 1500-2000 FT
DEEP OVER CENTRAL/EASTERN MN PER LAPS SOUNDINGS AND PILOT REPORTS.
MODEL SOUNDINGS SHOW THE MOISTURE UNDER THE 900-850MB INVERSION AS
WELL AS IN THE STABLE INVERSION LAYER. THIS PLUS THE INVERSION AND
DEPTH OF MOISTURE WILL MAKE THE CLOUDS VERY DIFFICULT TO ERODE/MIX
OUT. IT LOOKING LIKE WE WILL HAVE TO WAIT FOR THE CLOUDS TO ADVECT
OUT OF THE AREA TONIGHT/MON. BASED ON SATELLITE TRENDS WITH THE
DISTANCE-SPEED TOOL AND RUC LOW LEVEL MOISTURE FIELDS...CLEARING
EDGE OF THE CLOUDS DOES NOT REACH THE WEST EDGE OF THE FCST AREA
UNTIL 11Z MON. BULK OF OTHER MODELS MIX/ERODE THE TRAPPED LOW LEVEL
MOISTURE OUT OF MN/IA/WESTERN WI RATHER QUICKLY THIS
AFTERNOON/EVENING WHICH APPEARS VERY OPTIMISTIC. WINDS ACROSS
CENTRAL/NORTHERN MN DO BECOME SOUTHWEST LATE TONIGHT...WITH SOME
ACCELERATION OF THE EAST MOVEMENT OF THE CLOUDS EXPECTED NORTH OF
THE FCST AREA LATE TONIGHT AND ON MON. LAST TO SEE THE CLOUDS CLEAR
MON LOOKING TO BE THE SOUTHEAST END OF THE FCST AREA. THUS HAVE
UPDATED FCST GRIDS FOR MORE CLOUDS TONIGHT INTO MON. HAVE ALSO
RAISED LOWS TONIGHT WHERE SKIES EXPECTED TO REMAIN OVERCAST. HOWEVER
CONCERNED THAT MAY NOT HAVE RAISED THESE ENOUGH OVER THE SOUTHEAST
HALF OF THE FCST AREA WHERE CONFIDENCE IS PRETTY HIGH FOR CLOUDY
SKIES THRU THE NIGHT AND TO 15Z MON.
.LONG TERM...WEDNESDAY NIGHT THROUGH SATURDAY NIGHT
236 AM CST SUN NOV 27 2011
FAIRLY QUIET EXTENDED PERIOD WITH TWO SYSTEMS OF NOTE TO KEEP AN
EYE ON. SOME UNCERTAINTY EXISTS WITH A COLD FRONT THAT DROPS DOWN
THROUGH THE REGION ON THURSDAY WITH SOME OF THE PREVIOUS MODELS
SUGGESTING THAT SOME POST-FRONTAL SNOW COULD FORM. THE LATEST
TREND IS TO GO AWAY FROM THIS THOUGH WITH DRIER AIR IN LOW LEVELS
RESTRICTING ANY PRECIPITATION FROM MAKING IT TO THE GROUND. THE
NEXT CHANCES FOR ANY PRECIPITATION WILL BE ON SATURDAY NIGHT AS
ANOTHER COLD FRONT DROPS DOWN INTO THE REGION.
&&
.AVIATION...THROUGH 12Z MONDAY
552 AM CST SUN NOV 27 2011
MORNING IR SATELLITE IMAGERY/SURFACE OBSERVATIONS SHOWING WIDESPREAD
MVFR STRATUS ENTRENCHED ACROSS THE UPPER MISSISSIPPI RIVER VALLEY
REGION INCLUDING KRST/KLSE TAF SITES. IN ADDITION...A FAIRLY TIGHT
PRESSURE GRADIENT WAS PRODUCING NORTHWEST WINDS IN THE 15 TO 25 KT
RANGE ACROSS THE AREA. MAIN CONCERN CONTINUES TO BE ON HOW LONG THE
STRATUS LINGERS AS HIGH PRESSURE BUILDS IN FROM THE PLAINS. LATEST
RUC MODELS SOUNDING/BUFKIT SHOWS MOISTURE/STRATUS REMAINING TRAPPED
BELOW THE SUBSIDENCE INVERSION ASSOCIATED WITH THE HIGH THROUGH
TODAY AND INTO THIS EVENING. TRENDED MORE ON THE PESSIMISTIC SIDE...
KEEPING THE BKN-OVC MVFR STRATUS IN AT KRST THROUGH 01Z...THEN
SCATTERING OUT AFTERWARDS AS THE RIDGE AXIS MOVES OVERHEAD. AT
KLSE...THINKING THAT STRATUS SHOULD BREAK UP SOMETIME AROUND 06Z.
WINDS SHOULD SUBSIDE THROUGH THIS AFTERNOON AS THE PRESSURE GRADIENT
RELAXES A BIT...THEN GOING LIGHT LESS THAN 5KT BY 03Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
236 AM CST SUN NOV 27 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RRS/AJ
LONG TERM....HALBACH
AVIATION.....DAS