Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/23/12

AREA FORECAST DISCUSSION

NWS EUREKA CA

935 AM PST WED NOV 21 2012

.UPDATE...
UPDATED SKY/WX/POP/QPF GRIDS TO ACCOUNT FOR LATEST SHORT-TERM
SATELLITE AND RADAR TRENDS. WV IMAGERY AND RUC ANALYSIS DEPICT
MAIN SHORTWAVE TROUGH AXIS PAST THE COAST AND ALREADY BEGINNING TO
PUSH EAST OF OUR CWA. THERE IS ALSO ANOTHER VORT MAX ROUNDING THE
BASE OF THE TROUGH AS IT LIFTS OUT AND HEIGHTS QUICKLY RISE THIS
AFTERNOON. RAPIDLY INCREASING SUBSIDENCE AND THE AMOUNT OF
CLEARING OCCURRING ON AND OFF THE COAST ON VISIBLE IMAGERY SUPPORT
CUTTING SHOWER CHANCES ALTOGETHER THERE...BUT THE LAST DISTURBANCE
LEAVES A SHRED OF DOUBT FOR SOME ISOLATED/WIDELY SCATTERED SHOWER
ACTIVITY LINGERING ACROSS THE MTS OF THE NORTHCOAST INTERIOR AND
MAINLY DEL NORTE COUNTY THIS AFTERNOON. OTHERWISE EXPECT CLEARING
SKIES HEADING INTO TONIGHT WITH VALLEY FOG AND CHILLY TEMPS BY
THANKSGIVING MORNING. SUNNY BUT SEASONABLY COOL THANKSGIVING STILL
ON TAP. AAD

.PREV DISCUSSION... /ISSUED 350 AM PST WED NOV 21 2012/

SYNOPSIS...SHOWERS WILL DIMINISH THROUGH THE DAY TODAY WITH DRY
WEATHER RETURNING FOR THANKSGIVING DAY. RAIN CHANCES WILL RETURN
FOR AREAS PRIMARILY NORTH OF MENDOCINO COUNTY FRIDAY NIGHT INTO
SATURDAY.

SHORT TERM...A SHORTWAVE TROUGH WILL MOVE EAST OF THE REGION THIS
MORNING BRINGING AN END TO THE STRONGEST CONVECTION. HOWEVER WITH
COLD AIR ALOFT TODAY...SHOWER CHANCES WILL CONTINUE THROUGH THE
AFTERNOON. BY THIS EVENING UPPER LEVEL RIDGING WILL BEGIN TO BUILD
OVER THE WEST COAST. THIS SHOULD BRING ANY SHOWER ACTIVITY TO AN END
QUICKLY THIS EVENING...BUT WITH LINGERING LOW LEVEL MOISTURE
INTERIOR AND COASTAL VALLEYS WILL LIKELY FOG OVER TONIGHT INTO THE
MORNING HOURS ON THANKSGIVING. ONCE THE FOG MIXES OUT IN THE MORNING
TO EARLY AFTERNOON...GENERALLY CLEAR SKIES CAN BE EXPECTED FOR THE
REMAINDER OF THANKSGIVING WITH TEMPERATURES WARMING ABOVE NORMAL
WITH THE REGION IN THE HEART OF AN UPPER LEVEL RIDGE. RIDGING WILL
GENERALLY BE MAINTAINED THROUGH MUCH OF FRIDAY BEFORE A TROUGH AND
COLD FRONT DIVE SOUTH INTO THE NORTHERN HALF OF THE CWA FRIDAY NIGHT
INTO SATURDAY. THIS WILL BRING ANOTHER SHOT OF RAIN TO LOCATIONS
PRIMARILY NORTH OF MENDOCINO COUNTY THROUGH SATURDAY. RPA

LONG TERM...SUNDAY INTO WEDNESDAY. MODELS CONTINUE TO INDICATE A
BUILDING RIDGE OFFSHORE WHICH WILL MAINTAIN THE POSSIBILITY OF A
BACK DOOR FRONT CLIPPING THE AREA SUN OR MON. THE RIDGE IS FORECAST
TO SHIFT EAST MON INTO TUE WHICH WILL ALLOW FOR GENERALLY FAIR
WEATHER THROUGHOUT NW CALIFORNIA. AS SUCH, HAVE CONTINUED TO KEEP
POPS LOW LATE WEEKEND THROUGH MON. DESPITE A POSSIBLE BACKDOOR
FRONT, WEAK OFFSHORE FLOW IS LIKELY TO DEVELOP HELPING TO KEEP THE
LOWER ATMOSPHERE DRY. THIS WILL ALSO ALLOW FOR TEMPS TO WARM A BIT
ALONG THE COAST. KEPT TEMPS IN THE MID TO UPPER 50S DURING THIS
TIME, BUT MAY REACH INTO THE LOW 60S IF THE OFFSHORE FLOW DEVELOPS
WELL. BEYOND EARLY NEXT WEEK, BEGAN TO TREND THE POPS UPWARD TOWARD
CLIMO AS A LARGE UPPER TROUGH LOOKS TO BE APPROACHING BY LATE NEXT
WEEK. BFG

AVIATION...THE MOST ROBUST SHOWER ACTIVITY WILL COME TO AN END THIS
MORNING ACROSS NORTHWEST CALIFORNIA AS AN UPPER LEVEL SHORTWAVE
MOVES EAST OF THE AREA. HOWEVER A FEW LINGERING SHOWERS WILL
CONTINUE THROUGH THE DAY TODAY BEFORE FINALLY DIMINISHING THIS
EVENING AS UPPER LEVEL RIDGING BUILDS OVERHEAD. EXPECT MVFR
CONDITIONS AT THE COASTAL TAF SITES THIS MORNING...IMPROVING TO VFR
LATER THIS MORNING OR IN THE EARLY AFTERNOON. FARTHER
INLAND...TRAPPED LOW LEVEL MOISTURE IN INTERIOR VALLEYS MAY RESULT
IN PERIODS OF IFR THIS MORNING BEFORE IMPROVING TO VFR. VALLEY FOG
WILL DEVELOP TONIGHT AS SKIES CLEAR AND TEMPERATURES DROP. RPA

MARINE...AS OF 330AM A POST FRONTAL TROUGH IS NEARLY THROUGH THE
NRN WATERS AND CUTTING ACROSS WATERS S OF CAPE MENDOCINO ON ITS WAY
TO THE ENE. WINDS AHEAD OF THIS TROUGH ARE GENERALLY OUT OF THE SW
WITH THE HIGHEST WINDS N OF THE CAPE. BEHIND THIS TROUGH WINDS ARE
SHIFTING TO THE W AND NW AS A WEAK RIDGE BUILDS OVER THE REGION. A
WEAK SFC PRESSURE GRADIENT WILL PREVAIL THE NEXT FEW DAYS WITH LIGHT
TO MODERATE WINDS. MODELS SEEM TO BE FAIRLY CONSISTENT WITH A FRONT
COMING IN OVER THE WEEKEND THEN A SURGE OF HIGH PRESSURE BEHIND IT.
THUS NORTHERLY WINDS ARE FORECAST TO INCREASE ON SUN ALONG WITH
STEEP NORTHERLY WAVES. SEAS LOOK TO BE THE LARGEST IMPACT TODAY WITH
SOME SHORT PERIOD CHOP EARLY THIS MORNING AND A BUILDING W WAVE
GROUP. THE SHORT PERIOD CHOP IS EXPECTED TO DECAY QUICKLY THIS
MORNING AND MAY BE GONE BY SUNRISE. HOWEVER, THE W WAVES WILL
CONTINUE INTO LATE MORNING THEN SLOWLY SUBSIDE INTO EARLY THU
MORNING. SEAS WILL BOTTOM OUT ON THANKSGIVING AND MAY DROP AS LOW AS
4 TO 6 FT AT 11 SECONDS RIGHT UP NEAR THE COAST. SEAS WILL BUILD
AGAIN ON FRI AS ANOTHER WNW WAVE GROUP DEVELOPS. OVERALL, EASING
CONDITIONS THIS AFTERNOON THROUGH TURKEY DAY. BFG

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
NORTHWEST CALIFORNIA COASTAL WATERS...SMALL CRAFT ADVISORY UNTIL 3 AM PST THURSDAY PZZ450-455-470-475.

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AREA FORECAST DISCUSSION

NWS DENVER/BOULDER CO

1009 AM MST WED NOV 21 2012

.UPDATE...CURRENT FORECASTS STILL LOOKING ON TRACK. ANOTHER WARM
DAY EXPECTED WITH READINGS ABOVE NORMAL. WAVE CLOUD FORMING ALONG
NORTHERN FOOTHILLS WHICH MODELS AS WELL AS WRF SYNTHETIC SATELLITE
IMAGERY KEEP ALONG FOOTHILLS THROUGH THE AFTERNOON. SHOULD NOT BE
A FACTOR IN KEEPING TEMPS FROM REACHING THE 70S ACROSS THE
PLAINS. LOOKING LIKE DENVER MAY END UP A FEW DEGREES SHY OF THE
RECORD OF 73 DEGREES SET BACK IN 1974. WINDS TO INCREASE ACROSS
MOUNTAINS THROUGH THE DAY AS SOUTHWEST FLOW ALOFT INCREASES. COULD
STILL SEE SOME GUSTS AROUND 50 MPH TONIGHT. ACROSS PLAINS...LATEST
MODELS CONTINUE TO SHOW WEAK GRADIENT INTO THE EVENING. COLD FRONT
STILL ON TRACK TO MOVE ACROSS THE AREA AFTER MIDNIGHT. WINDS COULD
GET A BIT GUSTY ALONG FOOTHILLS AND ADJACENT PLAINS.

.AVIATION...CURRENT TAF TRENDS STILL LOOKING ON TRACK. LATEST NAM
AND RUC SHOWING WEAK ANTICYCLONE ACROSS THE DENVER AREA AFTER 21Z
WITH WEAK EASTERLIES ACROSS AREA AIRPORTS. DRAINAGE WINDS TO
REDEVELOP DURING THE EVENING. COLD FRONT STILL ON TRACK TO MOVE
ACROSS THE AREA AFTER MIDNIGHT WITH WINDS SHIFTING TO THE
NORTHWEST AND BECOMING NORTHERLY BY 12Z. VFR TO CONTINUE WITH
UNLIMITED CEILINGS.

.PREV DISCUSSION... /ISSUED 403 AM MST WED NOV 21 2012/

SHORT TERM...SOUTHWEST FLOW ALOFT WILL INCREASE TODAY AND TONIGHT
AS A TROUGH MOVES FROM THE PACIFIC NORTHWEST TO THE NORTHERN
ROCKIES. THIS PATTERN WILL BRING ONE MORE WARM DAY. AIRMASS WILL
WARM A COUPLE OF DEGREES FROM YESTERDAY. THERE IS A WAVE CLOUD OVER
FAR NORTHERN COLORADO AND WYOMING. MODELS SHOWING MOISTURE WILL HOLD
OFF FROM INCREASING UNTIL LATE THIS AFTERNOON AND EVENING. DO EXPECT
SOME WAVE CLOUDS THEN. DO NOT EXPECT MUCH FOR CLOUDS THIS MORNING OR
EARLY AFTERNOON...SO WE SHOULD GET GOOD HEATING. HIGHS WILL LIKELY
SURPASS YESTERDAY`S READINGS BY A COUPLE OF DEGREES...WHICH WILL PUT
A FEW LOCATIONS IN THE LOWER 70S.

COLD FRONT WILL PUSH THROUGH NORTHEAST COLORADO AFTER MIDNIGHT
TONIGHT. THIS WILL HELP TO KEEP THE AIRMASS MIXED...THUS LOW LYING
AREAS WILL NOT BE AS COLD AS PAST NIGHTS. WINDS WILL INCREASE OVER
THE MOUNTAINS AND HIGHER FOOTHILLS WITH GUSTS TO 50 MPH POSSIBLE.
MAY SEE SOME OF THE GUSTY WINDS MIX DOWN THE FOOTHILLS AND ACROSS
AREAS WEST OF I-25.

LONG TERM...OPERATIONAL MODELS STILL MARCH AN UPPER TROUGH
ACROSS THE NORTHERN ROCKY MTN STATES ON THURSDAY AND SLIDE A COLD
FRONT SOUTH ACROSS N-CENTRAL AND NERN COLORADO THURSDAY MORNING. A
RELATIVELY STG JET MAXIMA ROUNDING THE SOUTH SIDE OF THIS TROUGH
IS PROGGED TO PASS OVER THE COLORADO FRONT RANGE IN THE MORNING
AND BE OVER NERN COLORADO BY THE AFTERNOON. SHOULD SEE SOME OF
THIS HIGH ALTITUDE MOMENTUM MIXING DOWN TO THE GROUND DURING THE
DAY AS COLD AIR CONTINUES TO FUNNEL IN BEHIND THE COLD FRONT. THIS
FRONTAL SYSTEM LOOKS DRY...HOWEVER MAY STILL SEE A FEW LIGHT
OROGRAPHIC SNOW SHOWERS OVER THE PARK AND GORE RANGES WITH PASSAGE
OF THE 700-500 TROUGH AXIS IN THE MORNING. SHOULD ALSO SEE A
PERIOD OF STG W-NWLY BORA WINDS OVER THE HIGH MTN RIDGES AND EAST
FACING SLOPES OF THE FRONT RANGE DURING MAX COLD AIR ADVECTION
DURING THE MORNING AND EARLY AFTERNOON HRS. COULD SEE GUSTS IN THE
40-50 MPH RANGE. STRONG AND GUSTY N-NWLY WINDS ALSO A GOOD BET ON
THE PLAINS FOR MUCH OF THE DAY. BEST CHANCE FOR THESE WINDS
ROUGHLY EAST OF A FORT COLLINS TO LIMON LINE WHERE WINDS COULD
GUST 35-40 MPH. WIND SPEEDS IN BOTH AREAS ARE BELOW HIGH WIND
CRITERIA. OTHERWISE A COLDER DAY WITH TEMPERATURES SOME 15-20 DEG
F BELOW THOSE EXPECTED TODAY. HOWEVER THE 55 DEG F FCST FOR DENVER
IS STILL 6 DEG F ABOVE AVERAGE FOR THE DATE.

FOR FRIDAY...TEMPERATURES SLOW TO WARM EVEN THOUGH TEMPERATURE BEGIN
TO WARM ALOFT WITH AN UPPER RIDGE BUILDING IN OVER THE STATE. WITH
DOWNSLOPE FLOW DEVELOPING ALONG THE FRONT RANGE SHOULD SEE WARMEST
READINGS IN THIS AREA..BUT STILL NEAR TO SLIGHTLY ABOVE AVERAGE. MTN
RIDGE WILL ALSO CONTINUE TO DEAL WITH GUSTY W-NWLY WINDS WITH FAST
NWLY FLOW ALOFT.

FOR SATURDAY...A LARGE UPPER RIDGE WITH ITS ABOVE AVERAGE
TEMPERATURES AND LOW HUMIDITIES MOVES ACROSS THE STATE. ACCORDING TO
MODELS SHOULD SEE A 8-12 DEG F WARMUP IN SFC TEMPERATURES ON THE
PLAINS...AND NEARLY AS MUCH WARMING IN THE HIGH COUNTRY WITH LIGHTER
WINDS.

FOR SUNDAY THROUGH TUESDAY...THE WARM UPPER RIDGE OVER THE REGION
QUICKLY FLATTENS AND MOVES EAST OF THE AREA ON SUNDAY AS AN UPPER
LEVEL WAVE AMPLIFIES AS IT RACES SOUTHEAST OUT OF THE PACIFIC
NORTHWEST. OPERATIONAL MODELS SHOW THIS PROGRESSIVE UPPER AIR
SYSTEM REACHING COLORADO BY LATE ON SUNDAY. GFS MODEL EVEN SHOWS A
WEAK COLD FRONT DROPPING SOUTH INTO NERN COLORADO BEFORE ITS
ARRIVAL WHICH HELPS TO ELEVATE BNDRY LAYER MOISTURE ON THE PLAINS.
WHEREAS THE OTHER MODELS ABOUT 6-9 HOURS BEHIND THE GFS. ITS ON
MONDAY WHEN ESSENTIALLY ALL MODELS SHOW THE TROUGH HAVING THE
GREATEST IMPACT ON THE FORECAST AREA. TEMPERATURES AT THEIR
COLDEST UNDER MOSTLY CLOUDY TO OVERCAST SKIES. SINCE THE MAIN
BUNDLE OF ENERGY WITH THIS SYSTEM REMAINS NORTH OF COLORADO...DO
NOT SEE THIS SYSTEM BEING A BIG PRECIP PRODUCER FOR US. MONDAY
AFTERNOON NOW APPEARS TO BE TIME WHEN WE/LL SEE OUR BEST CHANCE
FOR PRECIP...I.E SNOW IN THE HIGH COUNTRY AND RAIN/SNOW AT LOWER
ELEVATIONS. COULD SEE LIGHT ACCUMULATION IN THE HIGH COUNTRY AND
POSSIBLY IN SPOTS ON THE PLACES...BUT TOO EARLY TO PIN DOWN.
SYSTEM MOVES OUT MONDAY NIGHT WITH DRIER AND SLIGHT WARMER
CONDITIONS EXPECTED FOR TUESDAY WITH A RETURN TO HIGH PRESSURE.

AVIATION...VFR CONDITIONS WILL PREVAIL TODAY WITH ONLY SOME HIGH
CLOUDS. SOUTHERLY WINDS THIS MORNING WILL WEAKEN AND SHIFT EASTERLY
THIS AFTERNOON. NORMAL DRAINAGE WINDS WILL DEVELOP THIS EVENING.
AFTER MIDNIGHT TONIGHT...A COLD FRONT WILL PUSH THROUGH THE AREA
BRINGING NORTHERLY WINDS BY 12Z.

.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM...D-L
LONG TERM....BAKER
AVIATION...D-L

AREA FORECAST DISCUSSION

NWS NEW YORK NY

935 AM EST WED NOV 21 2012

.SYNOPSIS...
HIGH PRESSURE ALONG THE EASTERN SEABOARD WILL REMAIN IN CONTROL OF
OUR WEATHER INTO FRIDAY. A COLD FRONT WILL MOVE ACROSS THE AREA
LATE FRIDAY NIGHT FOLLOWED BY HIGH PRESSURE BUILDING IN FROM THE
WEST THIS WEEKEND INTO EARLY NEXT WEEK. A COMPLEX STORM SYSTEM
APPROACHES THE AREA ON TUESDAY.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MINOR ADJUSTMENTS MADE THIS MORNING TO ACCOUNT FOR LATEST OBS.
FORECAST REMAINS ON TRACK.

CIRRUS FROM UPPER SHORTWAVE IS PROGRESSING EAST. HAVE FOLLOWED
LATEST RAP TIME-LAGGED ENSEMBLE FOR CLOUD GRIDS WHICH IS VERY
CLOSE TO OBSERVED TREND. THIS RESULTS IN A SUNNY OR BECOMING SUNNY
NORTH AND EAST FCST.

TEMPS TODAY ARE CLOSE TO GFS MOS. WHILE MAVS HAVE BEEN TOO WARM OF
LATE AND BIAS CORRECTED GRIDDED GFS MOS IS 3 DEGREES
COOLER...BELIEVE NEARLY FULL SUN WILL ALLOW THE 50 TO 55 FCST TO
VERIFY.

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
HIGH PRESSURE PERSISTS. THUS...CONTINUED WITH A PERSISTENCE FCST.
STRATUS DECK FROM GULF OF MAINE CLIPS SE CT AND LONG ISLAND
OVERNIGHT AS SEEN IN GFS LOW LEVEL RH FIELDS.

THANKSGIVING FINDS LIGHT NE WINDS AND MOSTLY SUNNY SKIES - A FINE
DAY FOR A PARADE...TRAVEL AND GIVING THANKS.

TEMPS ARE FCST JUST A TAD ABOVE NORMAL AND CLOSE TO GFS MOS.

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THE NAM IS A FAST OUTLIER WITH THE COLD FRONT FRIDAY AND FRIDAY
NIGHT...SO DISCARDED ITS GENERAL SOLUTION. USED A GFS/ECMWF/CMC-
GLOBAL BLEND THURSDAY NIGHT-MONDAY. THE GFS QUITE LIKELY...GIVEN
ITS KNOWN BIAS TO ERODE HIGHS OVER THE CANADIAN MARITIMES/NORTH
ATLANTIC TO QUICKLY...A BIT FAR N/W AND TOO FAST WITH THE SYSTEM
APPROACHING BY TUESDAY...SO LEANED TOWARDS TO THE ECMWF THERE
AFTER...NOTING SUPPORT FROM THE CMC-GLOBAL THROUGH 144 HOURS.

A DEEP LAYERED RIDGE CROSSES THE AREA THURSDAY NIGHT...GIVING WAY
TO AN APPROACHING FULL LATITUDE TROUGH FRIDAY AND FRIDAY NIGHT. THIS
TROUGH THEN CROSSES THE AREA SATURDAY AND SATURDAY NIGHT.

IN TERMS OF SENSIBLE WEATHER...THURSDAY NIGHT SHOULD BE DRY DUE TO
SUBSIDENCE UNDER THE RIDGE. HAVE SLIGHT CHANCE POPS IN FAR WESTERN
ZONES FRIDAY (CHANCE FAR W ORANGE) FRIDAY AFTERNOON...THEN CHANCE
POPS FOR ALL BUT FAR SW ZONES FRIDAY NIGHT WITH THE PASSAGE OF THE
SURFACE COLD FRONT. ALL GUIDANCE SUGGESTS THAT PRECIPITATION COULD
HAVE TROUBLE GETTING INTO NYC METRO FRIDAY NIGHT...SO ONLY SLIGHT
CHANCE POPS THERE. SLIGHT CHANCE POPS WEST/CHANCE POPS EVERYWHERE
SATURDAY DUE TO INSTABILITY AND LINGERING POST-FRONTAL SHOWERS.
APPEARS SHOULD HAVE ENOUGH LOW LEVEL COLD AIR WORK IN LATE FRIDAY
NIGHT THAT NW ZONES COULD SEE A -SHRA/-SHSN MIX AND POSSIBLE
CHANGE TO ALL SNOW SHOWERS SATURDAY MORNING. EXPECT SUFFICIENT
BOUNDARY LAYER WARMING THAT SHOULD SEE ONLY -SHRA IN THE
AFTERNOON. EXPECT GUSTY NW WINDS IN RESPONSE TO STRONG LOW LEVEL
COLD ADVECTION SATURDAY. SHOULD SEE SUFFICIENT DRYING BY SATURDAY
NIGHT WITH CONTINUING GUSTY NW WINDS TO GO WITH A DRY FORECAST
THEN.

NW FLOW ALOFT SUNDAY AND SUNDAY NIGHT GIVES WAY TO RIDGING
BUILDING IN MONDAY...WITH DRY CONDITIONS ACROSS THE REGION.

THE RIDGE SLIDES TO THE EAST MONDAY NIGHT. SW FLOW ALOFT ON
TUESDAY AHEAD OF A FULL LATITUDE TROUGH BUILDING INTO THE GREAT
LAKES AND MID- SOUTH. A SURFACE LOW SHOULD TRACK TO THE EASTERN
GREAT LAKES BY TUESDAY NIGHT. WITH ITS ASSOCIATED WARM FRONT
LIKELY STAYING TO OUR S MONDAY NIGHT AND TUESDAY...WENT WITH
STRATIFORM PRECIPITATION IN RESPONSE TO OVER RUNNING WITH SLIGHT
CHANCE POPS MONDAY NIGHT AND CHANCE POPS TUESDAY. FOR NOW HAVE A
WINTRY MIX CHANGING TO RAIN ACROSS NORTHERN INTERIOR ZONES...AND
JUST RAIN OVER SOUTHERN ZONES MONDAY NIGHT AND TUESDAY.

FOR TEMPERATURES THURSDAY NIGHT AND FRIDAY...USED A BLEND OF MAV/MET
GUIDANCE...MIXING IN NAM 2-METER TEMPERATURES AND MIXING DOWN FROM
950 HPA FOR HIGHS TUESDAY...WITH TEMPERATURES SLIGHTLY ABOVE
NORMAL IN BOTH PERIODS.

FROM FRIDAY NIGHT THROUGH TUESDAY USED A BLEND OF MEX/MEX ENSEMBLE
MEAN/HPC GUIDANCE...WEIGHING MORE AND MORE TOWARDS ECE GUIDANCE
TOWARDS THE END OF THE PERIOD. EXCEPT FOR NEAR NORMAL LOWS FRIDAY
NIGHT...EXPECT BELOW NORMAL TEMPERATURES IN THIS TIME FRAME.

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
HIGH PRES WILL MOVE SLOWLY SOUTHEAST ACROSS THE AREA THROUGH THANKSGIVING
DAY.

WIND FORECAST TODAY...NE WIND SPEEDS WERE INCREASED BY A FEW KTS
TO 10-12 KT.

VFR WEATHER IS FORECAST THROUGH SUNSET. THERE IS A LOW POTENTIAL FOR
CIGS AROUND 3K FT TO DEVELOP KISP-KGON AFT 16-18Z. MVFR STRATUS LIKELY
TO DEVELOP TNGT. THIS SHOULD OVERSPREAD THE AREA FROM THE E. MVFR HAS
BEEN INCLUDED IN THE TAFS. POTENTIAL EXISTS FOR THIS STRATUS TO REMAIN
OFFSHORE...BUT THE PROB IS HIGHER THAT IT WILL IMPACT THE AREA TERMINALS
ATTM.

BAND OF MVFR EXPECTED TO ERODE DURING THE DAY ON THU...WITH VFR BY
AFTN.

NY METRO ENHANCED AVIATION WEATHER SUPPORT...

DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)

KEWR FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.

KJFK FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

KLGA FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

KTEB FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

KHPN FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

KISP FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

.OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY...
.THURSDAY...MVFR IN THE MRNG. VFR IN THE AFTN. NE FLOW AROUND 10KT.
.THURSDAY NIGHT-FRIDAY...VFR.
.FRIDAY NIGHT...COLD FROPA...ACCOMPANIED BY SCT RAIN SHOWERS WITH
POSSIBLE BRIEF MVFR CONDS. NW WINDS G25-30KT BEHIND FROPA.
.SATURDAY...SOME SNOW FLURRIES POSSIBLE NW OF CITY TERMINALS. NW
WINDS G25-30KT.
.SUNDAY...GUSTY NW WINDS G15-20KT.

.MARINE...
FORECAST REMAINS ON TRACK.

PERSISTENT NE FLOW CONTINUES THROUGH EARLY FRIDAY BETWEEN INLAND
HIGH PRESSURE AND A DISTANT OCEAN LOW. WINDS REMAIN BELOW SCA
LEVELS...BUT OCEAN SEAS WILL REMAIN IN THE 5-7 FT RANGE VIA SE
SWELL FROM THE OFFSHORE LOW.

SEAS WILL REMAIN RATHER ROUGH ON THE OCEAN WATERS THURSDAY INTO
FRIDAY DUE TO EASTERLY SWELL.

LINGERING SE SWELLS SHOULD KEEP SEAS AT SCA LEVEL FRIDAY
NIGHT...WITH SUB-SCA CONDITIONS ELSEWHERE. GALE FORCE GUSTS LIKELY
ON ALL WATERS SATURDAY...DUE TO STRONG LOW LEVEL COLD ADVECTION.
THESE GUSTS COULD LINGER INTO EARLY SUNDAY. AT LEAST SCA
CONDITIONS EXPECTED ON SUNDAY.

.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION EXPECTED THROUGH MONDAY.

.EQUIPMENT...
THE KOKX WSR-88D IS OUT OF SERVICE DUE TO A MAJOR NON STORM
RELATED MECHANICAL FAILURE. THE RADAR IS EXPECTED TO RETURN TO
SERVICE BY THE FIRST WEEK OF DECEMBER.

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EST FRIDAY
FOR ANZ350-353-355.

$$
SYNOPSIS...MALOIT/TONGUE
NEAR TERM...MALOIT/TONGUE
SHORT TERM...TONGUE
LONG TERM...MALOIT
AVIATION...GC
MARINE...MALOIT/TONGUE
HYDROLOGY...MALOIT/TONGUE
EQUIPMENT...

AREA FORECAST DISCUSSION

NWS NEW YORK NY

622 AM EST WED NOV 21 2012

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MINOR UPDATES TO THE GRIDS TO REFLECT THE LATEST TRENDS IN
OBSERVATIONS AND GUIDANCE. FORECAST APPEARS ON TRACK.

TEMPS TODAY ARE CLOSE TO GFS MOS. WHILE MAVS HAVE BEEN TOO WARM OF
LATE AND BIAS CORRECTED GRIDDED GFS MOS IS 3 DEGREES
COOLER...BELIEVE NEARLY FULL SUN WILL ALLOW THE 50 TO 55 FCST TO
VERIFY.

THANKSGIVING FINDS LIGHT NE WINDS AND MOSTLY SUNNY SKIES - A FINE
DAY FOR A PARADE...TRAVEL AND GIVING THANKS.

TEMPS ARE FCST JUST A TAD ABOVE NORMAL AND CLOSE TO GFS MOS.

A DEEP LAYERED RIDGE CROSSES THE AREA THURSDAY NIGHT...GIVING WAY
TO AN APPROACHING FULL LATITUDE TROUGH FRIDAY AND FRIDAY NIGHT. THIS
TROUGH THEN CROSSES THE AREA SATURDAY AND SATURDAY NIGHT.

NW FLOW ALOFT SUNDAY AND SUNDAY NIGHT GIVES WAY TO RIDGING
BUILDING IN MONDAY...WITH DRY CONDITIONS ACROSS THE REGION.

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
HIGH PRES WILL BUILD SWD OVER THE REGION THRU THANKSGIVING.

LGT NE WINDS THRU THE TAF PERIOD. SPEEDS AROUND 10KT DURING THE
DAYTIME HRS.

MAINLY VFR TODAY WITH MID AND HIGH CLOUDS. LOW POTENTIAL FOR CIGS
AROUND 3K FT TO DEVELOP KISP-KGON AFT 16-18Z. MVFR STRATUS LIKELY TO
DEVELOP TNGT. THIS SHOULD OVERSPREAD THE AREA FROM THE E. MVFR HAS
BEEN INCLUDED IN THE TAFS. POTENTIAL EXISTS FOR THIS STRATUS TO
REMAIN OFFSHORE...BUT THE PROB IS HIGHER THAT IT WILL IMPACT THE
AREA TERMINALS ATTM.

BAND OF MVFR EXPECTED TO ERODE DURING THE DAY ON THU...WITH VFR BY
AFTN.

NY METRO ENHANCED AVIATION WEATHER SUPPORT...

DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)

KEWR FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.

KJFK FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

KLGA FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

KTEB FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

KHPN FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

KISP FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

.OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY...
.THURSDAY...MVFR IN THE MRNG. VFR IN THE AFTN. NE FLOW AROUND 10KT.
.THURSDAY NIGHT-FRIDAY...VFR.
.FRIDAY NIGHT...COLD FROPA...ACCOMPANIED BY SCT SHOWERS WITH
POSSIBLE BRIEF MVFR CONDS. NW WINDS G25-30KT BEHIND FROPA.
.SATURDAY...SOME SNOW FLURRIES POSSIBLE NW OF CITY TERMINALS. NW
WINDS G25-30KT.
.SUNDAY...GUSTY NW WINDS G15-20KT.

.MARINE...
MINOR CHANGES TO THE GRIDS TO REFLECT THE LATEST TRENDS IN
OBSERVATIONS AND GUIDANCE. FORECAST APPEARS ON TRACK.

SEAS WILL REMAIN RATHER ROUGH ON THE OCEAN WATERS THURSDAY INTO
FRIDAY DUE TO EASTERLY SWELL.

.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION EXPECTED THROUGH MONDAY.

.EQUIPMENT...
THE KOKX WSR-88D IS OUT OF SERVICE DUE TO A MAJOR NON STORM
RELATED MECHANICAL FAILURE. THE RADAR IS EXPECTED TO RETURN TO
SERVICE BY THE FIRST WEEK OF DECEMBER.

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EST FRIDAY
FOR ANZ350-353-355.

SYNOPSIS...TONGUE/MALOIT
NEAR TERM...MALOIT/TONGUE
SHORT TERM...TONGUE
LONG TERM...MALOIT
AVIATION...12
MARINE...MALOIT/TONGUE
HYDROLOGY...TONGUE/MALOIT
EQUIPMENT...

AREA FORECAST DISCUSSION

NWS NEW YORK NY

347 AM EST WED NOV 21 2012

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CIRRUS FROM UPPER SHORTWAVE IS PROGRESSING EAST. HAVE FOLLOWED
LATEST RAP TIME-LAGGED ENSEMBLE FOR CLOUD GRIDS WHICH IS VERY
CLOSE TO OBSERVED TREND. THIS RESULTS IN A SUNNY OR BECOMING SUNNY
NORTH AND EAST FCST.

TEMPS TODAY ARE CLOSE TO GFS MOS. WHILE MAVS HAVE BEEN TOO WARM OF
LATE AND BIAS CORRECTED GRIDDED GFS MOS IS 3 DEGREES
COOLER...BELIEVE NEARLY FULL SUN WILL ALLOW THE 50 TO 55 FCST TO
VERIFY.

THANKSGIVING FINDS LIGHT NE WINDS AND MOSTLY SUNNY SKIES - A FINE
DAY FOR A PARADE...TRAVEL AND GIVING THANKS.

TEMPS ARE FCST JUST A TAD ABOVE NORMAL AND CLOSE TO GFS MOS.

A DEEP LAYERED RIDGE CROSSES THE AREA THURSDAY NIGHT...GIVING WAY
TO AN APPROACHING FULL LATITUDE TROUGH FRIDAY AND FRIDAY NIGHT. THIS
TROUGH THEN CROSSES THE AREA SATURDAY AND SATURDAY NIGHT.

NW FLOW ALOFT SUNDAY AND SUNDAY NIGHT GIVES WAY TO RIDGING
BUILDING IN MONDAY...WITH DRY CONDITIONS ACROSS THE REGION.

.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
HIGH PRES WILL BUILD SWD OVER THE REGION THRU THANKSGIVING.

LGT NE WINDS THRU THE TAF PERIOD. SPEEDS AROUND 10KT DURING THE
DAYTIME HRS.

NY METRO ENHANCED AVIATION WEATHER SUPPORT...

DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP://WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)

KEWR FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.

KJFK FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

KLGA FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

KTEB FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

KHPN FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

KISP FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

.OUTLOOK FOR 06Z THURSDAY THROUGH SUNDAY...
.THURSDAY...MVFR IN THE MRNG. VFR IN THE AFTN. NE FLOW AROUND 10KT.
.THURSDAY NIGHT-FRIDAY...VFR.
.FRIDAY NIGHT...COLD FROPA...ACCOMPANIED BY SCT SHOWERS WITH
POSSIBLE BRIEF MVFR CONDS. NW WINDS G25-30KT BEHIND FROPA.
.SATURDAY...SOME SNOW FLURRIES POSSIBLE NW OF CITY TERMINALS. NW
WINDS G25-30KT.
.SUNDAY...GUSTY NW WINDS G15-20KT.

.MARINE...
PERSISTENT NE FLOW CONTINUES THROUGH EARLY FRIDAY BETWEEN INLAND
HIGH PRESSURE AND A DISTANT OCEAN LOW. WINDS REMAIN BELOW SCA
LEVELS...BUT OCEAN SEAS WILL REMAIN IN THE 5-7 FT RANGE VIA SE
SWELL FROM THE OFFSHORE LOW.

THE HIGH SHOULD EVENTUALLY GIVE WAY TO A COLD FRONT FRIDAY NIGHT.
WINDS WILL INCREASE BEHIND THIS FRONT...AND SHOULD BE AT THEIR
STRONGEST SAT AFTERNOON AND SAT NIGHT. IN FACT...GUSTS COULD
APPROACH GALE FORCE DURING THIS TIME AS MUCH COLDER AIR RUSHES IN.

WINDS ABATE SOMEWHAT SUNDAY...BUT WILL REMAIN GUSTY AS HIGH PRESSURE
BUILDS WELL TO THE SOUTH.

SEAS WILL REMAIN RATHER ROUGH ON THE OCEAN WATERS THURSDAY INTO
FRIDAY DUE TO EASTERLY SWELL.

.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION EXPECTED THROUGH MONDAY.

.EQUIPMENT...
THE KOKX WSR-88D IS OUT OF SERVICE DUE TO A MAJOR NON STORM
RELATED MECHANICAL FAILURE. THE RADAR IS EXPECTED TO RETURN TO
SERVICE BY THE FIRST WEEK OF DECEMBER.

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EST FRIDAY
FOR ANZ350-353-355.

SYNOPSIS...TONGUE/MALOIT
NEAR TERM...TONGUE
SHORT TERM...TONGUE
LONG TERM...MALOIT
AVIATION...12
MARINE...TONGUE/MALOIT
HYDROLOGY...TONGUE/MALOIT
EQUIPMENT...

AREA FORECAST DISCUSSION

NWS TAMPA BAY RUSKIN FL

610 PM EST THU NOV 22 2012

...PATCHY FROST EXPECTED OVER INTERIOR NATURE COAST ZONES LATE
TONIGHT...

...LIGHT FREEZE POSSIBLE SATURDAY NIGHT FOR INTERIOR NATURE COAST
ZONES...

.UPDATE...
23Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS MID/UPPER LEVEL HEIGHTS
CONTINUING TO RISE OVER THE FL PENINSULA AS SHARP TROUGHING PULLS
EAST INTO THE WESTERN ATLANTIC AND IS REPLACED BY LONGWAVE RIDGING
ALONG THE EASTERN SEABOARD. A POTENT NORTHERN STREAM SHORTWAVE CAN
BE SEEN DIGGING SOUTH AND EAST OVER THE UPPER MIDWEST THIS EVENING.
THIS ENERGY WILL REPLACE THE CURRENT UPPER RIDGE AS IT EVOLVE INTO
A LONGWAVE EAST COAST TROUGH FOR THE FIRST HALF OF THE UPCOMING
WEEKEND. MOMENTUM ASSOCIATED WITH THIS TROUGH WILL ALSO HELP PUSH
ANOTHER REINFORCING COLD FRONT THROUGH THE REGION ON SATURDAY.

AT THE SURFACE...1020+MB HIGH PRESSURE EXTENDS FROM THE CENTRAL GULF
OF MEXICO TO GA/AL AND THEN NORTHEASTWARD TO THE MID-ATLANTIC
STATES. THIS RIDGE HAS MADE SOME PROGRESS EASTWARD TODAY AND THE
RESULTING LOCAL GRADIENT HAS WEAKENED. THE GRADIENT IS WEAKEST TO
THE NORTH OF I-4...AND IT WILL BE ACROSS THESE ZONES WHERE THE BEST
CHANCES FOR COMPLETE BOUNDARY LAYER DE-COUPLING WILL OCCUR AFTER
MIDNIGHT. THESE GOOD RADIATIONAL COOLING CONDITIONS SHOULD ALLOW
NORMALLY COLDER SECTION OF THE NATURE COAST ZONES TO BRIEFLY DROP
INTO THE MIDDLE 30S LATE TONIGHT. TEMPS IN THE MID 30S...SMALL
DEWPOINT DEPRESSION AND THE LIGHT/CALM WINDS SHOULD SUPPORT PATCHY
FROST TOWARD SUNRISE. THOSE WITH SENSITIVE OUTDOOR VEGETATION TO THE
NORTH OF THE I-4 CORRIDOR...ESPECIALLY FROM BROOKSVILLE TO CHIEFLAND
SHOULD TAKE NECESSARY FROST PRECAUTIONS. ELSEWHERE...TEMPERATURES
WIDESPREAD IN THE 40S ARE EXPECTED AWAY FROM THE COAST. IF WINDS CAN
DIMINISH ENOUGH...THEN A FEW READINGS IN THE UPPER 30S WILL ALSO BE
POSSIBLE FOR NORMALLY COLDER LOCATIONS OF HARDEE...DESOTO...AND
HIGHLANDS COUNTIES.

STACKED RIDGING/SYNOPTIC SUBSIDENCE WILL PROVIDE THE LOCAL AREA WITH
A DRY AND PLEASANT FRIDAY. PLENTY OF SUNSHINE WILL YIELD THE
INSOLATION FOR TEMPS TO REBOUND INTO THE LOWER 70S NORTH AND
LOWER/MID 70S SOUTH.

NEXT COLD FRONT WILL BE APPROACHING THE I-10 CORRIDOR FRIDAY
EVENING...AND THEN CROSS OUR REGION LATE FRIDAY NIGHT AND SATURDAY.
VERY LITTLE IN THE WAY OF COLUMN MOISTURE SHOULD RESULT IN THIS
BEING A DRY FRONTAL PASSAGE...AND RAIN CHANCES ARE BELOW 10%. A
REINFORCING SHOT OF COOL/DRY AIR WILL QUICKLY ADVECT ACROSS THE
PENINSULA IN THE WAKE OF THIS FRONT. SURFACE HIGH PRESSURE WILL ALSO
QUICKLY BUILD EASTWARD ALONG THE NORTHERN GULF COAST. IF CURRENT NWP
GUIDANCE HOLDS...THEN THE RIDGE WILL LIKELY BE CLOSE ENOUGH TO ALLOW
ANOTHER GOOD RADIATIONAL COOLING SETUP TO THE NORTH OF TAMPA BAY.
CURRENT MOS NUMBERS FROM BROOKSVILLE NORTHWARD TO CHIEFLAND AND
CROSS CITY SUGGEST WE MAY BE DEALING WITH A POTENTIAL LIGHT FREEZE
LATE SATURDAY NIGHT/EARLY SUNDAY MORNING. THOSE WITH AGRICULTURAL
INTERESTS TO THE NORTH OF I-4 SHOULD MONITOR FUTURE FORECASTS
CLOSELY. FROM I-4 SOUTHWARD...FREEZING TEMPERATURES ARE UNLIKELY...
HOWEVER WIDESPREAD UPPER 30S AND 40S ARE IN THE FORECAST.

.AVIATION...
VFR CONDITIONS ARE EXPECTED FOR THE NEXT 24 HOURS.

.MARINE...
A RIDGE OF HIGH PRESSURE OVER THE GULF AND AN AREA OF LOW PRESSURE
IN THE ATLANTIC WILL CREATE A STRONG NORTHERLY WIND OVER THE WATERS
OFF WEST CENTRAL AND SOUTHWEST FLORIDA TODAY. WINDS WILL CONTINUE TO
REACH CAUTIONARY CRITERIA AT TIMES THROUGH THIS EVENING. HIGH
PRESSURE BUILDING INTO THE NORTHEAST GULF WILL DIMINISH WINDS BELOW
HEADLINE CRITERIA BY LATE TONIGHT AND THROUGH THE DAY ON FRIDAY.
ANOTHER COLD FRONT WILL CROSS THE FORECAST WATERS LATE FRIDAY NIGHT
AND SATURDAY FOLLOWED BY ANOTHER PERIOD OF NEAR CAUTIONARY LEVEL
NORTHERLY WINDS.

.PRELIMINARY POINT TEMPS/POPS...
TPA 48 73 54 72 / 0 0 10 0
FMY 47 74 51 76 / 0 0 0 0
GIF 42 74 47 74 / 0 0 10 0
SRQ 47 73 52 72 / 0 0 10 10
BKV 34 73 45 71 / 0 0 10 0
SPG 55 71 59 71 / 0 0 10 10

.TBW WATCHES/WARNINGS/ADVISORIES...
FL...FIRE WEATHER WATCH FROM FRIDAY MORNING THROUGH FRIDAY
AFTERNOON FOR LEE-PINELLAS-SARASOTA.

GULF WATERS...NONE.

UPDATE...MROCZKA
AVIATION...CLOSE

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

353 AM CST WED NOV 21 2012

.DISCUSSION...
922 PM CST

HAVE EXPANDED THE DENSE FOG ADVISORY TO INCLUDE THE REMAINDER OF
THE FORECAST AREA...INCLUDING ALL OF CHICAGO...AS OBSERVATIONAL
GUIDANCE CONTINUES TO FALL IN LINE WITH THE IDEAL SYNOPTIC AND
MESOSCALE PATTERNS FOR DENSE FOG.

NOT MUCH TO ADD FROM PREVIOUS REASONING IN DISCUSSIONS BELOW. THE
00Z DVN SOUNDING REVEALED A CLASSIC FOG SOUNDING GOING INTO THE
EVENING. THE AREA OF PERSISTENT DENSE FOG CENTERED ON THE
MISSISSIPPI RIVER CONTINUES TO EXPAND EASTWARD...LINING UP WITH
THE SURFACE RIDGE AXIS PERFECTLY. OFF OF LAKE MICHIGAN INTO
NORTHWEST IN/SOUTHWEST MI...DENSE FOG HAS DEVELOPED/EXPANDED
INLAND DUE LIKELY TO SLIGHTLY HIGHER MOISTURE...ALTHOUGH IT SEEMS
PATCHY TO AREAS AT TIMES BASED ON WEBCAMS AND REPORTS. AS FOR
IN-BETWEEN THESE TWO PRONOUNCED AREAS...THE ATMOSPHERE SHOULD
CONTINUE TO SATURATE AND FORECAST SOUNDINGS INDICATE DENSE FOG
FOR MUCH OF THE OVERNIGHT AND INTO WEDNESDAY MORNING. SOME CONCERN
THIS FOG COULD LAST ALL THE WAY TO NOON. NO MATTER WHAT...THIS
WILL HAVE IMPACTS ON ANY EARLY TO MID MORNING HOLIDAY TRAVELERS.
IN ADDITION...HAVE FURTHER STIFLED THE TYPICAL DIURNAL TEMPERATURE
INCREASE WEDNESDAY MORNING...AND LOWERED HIGH TEMPERATURES BY 2-3
DEGREES. THESE MAY END UP NEEDING TO BE LOWERED MORE...AS THE LATE
NOVEMBER LOW SUN ANGLE WILL HAVE SOME DIFFICULTY ERODING THIS FOG.

MTF

//PREV DISCUSSION...
628 PM CST

HAVE SPED UP THE START TIME OF THE DENSE FOG IN THE FORECAST...AND
WITH FURTHER INCREASED CONFIDENCE ON THE AREA TO MOST LIKELY BE
IMPACTED...HAVE GONE AHEAD AND ISSUED A DENSE FOG ADVISORY FOR
NORTH CENTRAL ILLINOIS AND FAR WESTERN AND NORTHERN AREAS OF THE
CHICAGO METROPOLITAN AREA. THIS MAY VERY WELL NEED TO BE EXPANDED
IN TWO TO THREE HOURS.

WINDS HAVE BECOME CALM OR LIGHT AND VARIABLE ACROSS THE ENTIRE
AREA EARLY THIS EVENING AS THE RIDGE AXIS HAS EXPANDED INTO
NORTHERN IL. DEW POINTS REMAIN ANOMALOUSLY HIGH WITH MID 40S...AND
TEMPERATURE DROPS AT A HANDFUL OF SITES HAVE BEEN AROUND OR EVEN
HIGHER THAN 10F SINCE 4 PM. THIS HAS RESULTED IN T/TD SPREADS OF
LESS THAN 5F ALREADY ACROSS NORTH CENTRAL IL. IN ADDITION..THE
AREAS OF FOG THAT PERSISTED THROUGH TODAY IN EASTERN IA/FAR
SOUTHWEST WI THAT WERE MENTIONED IN THE PRIOR DISCUSSION HAVE ONLY
BLOSSOMED SINCE SUNDOWN. VISIBILITY OBSERVATIONS IN THESE AREAS
ARE ALMOST ALL AT ONE QUARTER MILE OR LESS. SO WITH THE RIDGE AXIS
ONLY FURTHER TRANSITIONING OVER THE AREA THROUGH LATE
EVENING...WOULD EXPECT VISIBILITY TO DROP AND ESPECIALLY RAPID IN
THOSE AREAS WHERE THE PERSISTING FOG EXPANDS IN /WESTERN WINNEBAGO
AND OGLE COUNTIES BY 830 PM/. THE HRRR FORECAST VISIBILITY AGREES
WITH THIS IDEA OF EASTWARD EXPANSION THROUGH LATE EVENING AND
OVERNIGHT.

AS FOR AREAS TO THE EAST...INCLUDING MUCH OF
CHICAGOLAND...WIDESPREAD 3-6 SM VISIBILITIES EXIST. THESE
VISIBILITIES AND WEBCAMS HAVE INDICATED VERY GRADUAL VISIBILITY
REDUCTION SINCE SUNDOWN. LINGERING CLOUDS AND ASSOCIATED MOIST
LAYER AROUND 3K FT ARE LIKELY IMPAIRING FULL RADIATIONAL COOLING
SOMEWHAT...BUT DO FULLY EXPECT THESE AREAS TO COOL MORE QUICKLY
AND DENSE FOG AT LEAST IN PLACES TO DEVELOP. AREAS NEAR THE LAKE
MAY ACTUALLY BECOME MORE FAVORED TO SEE THE FOG MORE QUICKLY DUE
TO A LIGHT BUT MOIST ONSHORE COMPONENT.

IMPROVEMENT IN THE FOG ON WEDNESDAY MORNING MAY BE EXTREMELY
SLOW...WITH SOME AREAS OF FOG LASTING INTO THE EARLY AFTERNOON
GIVEN WHAT OCCURRED UPSTREAM IN EASTERN IOWA TODAY AND JUST THE
CLIMATOLOGY OF THIS TIME OF YEAR. WILL FURTHER ASSESS THIS WITH
00Z GUIDANCE.

MTF

//PREV DISCUSSION...
256 PM CST

TONIGHT THROUGH WEDNESDAY...
GREATEST CONCERN FOR TONIGHT RESIDES WITH THE EXPECTED DEVELOPMENT
OF FOG...TRANSITIONING INTO AREAS OF DENSE FOG OVERNIGHT. THE
OTHER CONCERN IS THAT ONE OF THE BUSIEST TRAVEL DAYS OF THE YEAR
WILL HAVE A SLOW START GIVEN THE EXPECTED DEVELOPMENT OF FOG.

LOOKING UPSTREAM ACROSS EASTERN IOWA FOG HAS LINGERED INTO THIS
AFTERNOON...WITH A FEW LOCATIONS STILL SEEING VSBYS DOWN AROUND 1 TO
2 MILES. THIS AFTN HAS SEEN ALMOST NO MIXING WITH LGT WINDS
GENERALLY LESS THAN 5 MPH...AND DEW POINTS HOLDING UP IN THE MID 40S
FOR MANY LOCATIONS OF NORTHERN IL/NORTHWEST IN. HIGH PRESSURE WILL
REMAIN OVERHEAD TONIGHT...WHICH WILL AID IN DECENT RADIATIONAL
COOLING SHORTLY AFTER SUNSET. THIS ALL POINTS TOWARDS A REPEAT NIGHT
OF AREAS OF FOG AND POTENTIALLY AREAS OF DENSE FOG. OVERNIGHT LOWS
WILL COOL INTO THE LOW 40S...WITH THE EXCEPTION OF AREAS ADJACENT TO
LAKE MICHIGAN WHERE TEMPS MAY HOLD IN THE MID 40S.

ONCE THE FOG DOES DEVELOP IT WILL MOST LIKELY LINGER INTO WED
MORNING...POSSIBLY THROUGH MIDDAY. GIVEN THE SCENARIO OF WHAT HAS
TRANSPIRED ACROSS EASTERN IOWA...COULD SEE THE DENSE FOG LIFT BY
MID-MORNING THEN PATCHY FOG THROUGH NOON. THIS WILL RESULT IN
TEMPERATURES BEING SLOW TO WARM...THUS HAVE SLOWED THE RATE OF CLIMB
UNTIL MIDDAY. THROUGHOUT THE MORNING HOURS TEMPS WILL REMAIN IN THE
LOW/MID 40S...THEN BY MIDDAY AND IMPROVING VSBYS OR BURNING OFF
FOG...TEMPS WILL BEGIN TO CLIMB RAPIDLY INTO THE UPR 50S AND
POSSIBLY 60 DEG IN A FEW LOCATIONS. OTHERWISE SKIES WILL BECOME
MOSTLY CLEAR IN THE AFTERNOON HOURS.

CONFIDENCE...HIGH.
CONFIDENCE ON AREAS OF DENSE FOG...MEDIUM/HIGH.

THANKSGIVING...
500MB RIDGE REMAINS OVERHEAD...WITH A POTENT THERMAL RIDGE AT 850MB
OF 10 TO 12 DEG C. A FEW ENSEMBLE MEMBERS SUGGEST THAT 850MB TEMPS
COULD BE SLIGHTLY WARMER TO 14 DEG C. THE BETTER PRESSURE GRADIENT
REMAINS DISPLACED TO THE NORTHWEST OF THE REGION...WHICH IS THE AREA
THAT WILL SEE THE STRONGEST WARM AIR ADVECTION. EITHER WAY...IT
APPEARS THANKSGIVING WILL END UP BEING A RATHER WARM DAY WITH TEMPS
LIKELY TO REACH THE LOW 60S. PLUMES CONTINUE TO INDICATE A HIGH
CONFIDENCE THAT TEMPS WILL EASILY PUSH TO 60 DEGREES BY NOON. THE
LARGEST CAVEAT COULD BE THAT INCREASED MOISTURE APPEARS TO BE
PROGGED TO POOL ALONG THE BOUNDARY INTO THE MID-MISSISSIPPI
VALLEY...WHICH COULD PUSH CLOUDS OVERHEAD BY LATE MORNING. THIS
MAINLY WILL AFFECT THE WESTERN HALF OF THE CWFA. IN ADDITION HAVE
OVERSPREAD A SLIGHT CHC OF PRECIP BY MIDDAY ALONG AND NORTH OF A LA
SALLE TO CRYSTAL LAKE LINE. THEN ADDITIONAL MOISTURE CONTINUES TO
POUR INTO THE CWFA BY MID-AFTERNOON/EVENING...SO HAVE MAINTAINED
MENTION OF SLT CHC OF RA.

CONFIDENCE IN TEMPS...HIGH.
CONFIDENCE IN PRECIP...LOW.

FRIDAY THROUGH MONDAY...
ENSEMBLES THROUGH THE EXTENDED PERIODS CONTINUE TO SHOW MINIMAL
SPREAD IN ENVELOPE OF SOLUTIONS...LEADING TO THE INCREASED
CONFIDENCE THAT A PATTERN CHANGE IS UPON US. FRIDAY WILL KICK OFF
THE EXTENDED WITH A TASTE OF COLDER AIR...HOWEVER WHAT APPEARS TO BE
TAKING SHAPE FOR MID/LATE NEXT WEEK WILL BE MUCH MORE SIGNIFICANT AS
THE CALENDAR APPROACHES THE FIRST OF DECEMBER.

GUIDANCE CONTINUES TO PROG FRONTAL PASSAGE FOR THE FIRST HALF OF
FRI...POSSIBLY PRIOR TO DAYBREAK. VERY TIGHT PRESSURE GRADIENT IS
ALSO POISED TO ARRIVE BEHIND THE FRONTAL PASSAGE FRI...RESULTING IN
BREEZY CONDITIONS. WITH COOLER AIR STEADILY ADVECTING IN FROM THE
NORTHWEST AS A RESULT OF AN 850MB THERMAL TROUGH OF -10 TO -14 DEG
C...MAX TEMPS FRI COULD BE ACHIEVED PRIOR TO MID-MORNING. THEN IT
APPEARS FALLING TEMPS WILL OCCUR EARLY IN THE AFTERNOON. AT THIS
TIME IT APPEARS A DRY WEDGE WILL OCCUR FRI...SHIFTING ANY MOISTURE
EAST OF THE CWFA. THEN THE TRANSITION TOWARDS LAKE EFFECT PRECIP
DEVELOPS FRI AFTERNOON THROUGH SATURDAY EVENING...WHICH FORTUNATELY
WITH A STRONG WEST/NORTHWEST FLOW THIS PRECIP WILL BE DISPLACED
DOWNSTREAM ACROSS LOWER MICHIGAN AND PERHAPS PORTIONS OF NORTHWEST
INDIANA.

SAT/SUN WILL SEE ANTI-CYCLONIC FLOW PUSH BACK OVERHEAD WITH DRY
WEATHER EXPECTED THROUGH THE WEEKEND INTO EARLY MON. 500MB TROUGH
PIVOTS EAST WITH A RELATIVELY FLAT OR SEMI-ZONAL FLOW SUN/MON. SAT
HIGH TEMPS WILL STRUGGLE TO WARM INTO THE MID/UPR 30S. SUN/MON WILL
BEGIN TO WARM MARGINALLY INTO THE LOW 40S. THIS ALL APPEARS TO BE
TEMPORARY AS THE DEVELOPMENT OF A BLOCKING PATTERN BEGINS TO TAKE
SHAPE OVER ALASKA AND THE NORTH ATLANTIC...WHICH WILL ULTIMATELY
ALLOW MUCH COLDER AIR TO ARRIVE INTO CENTRAL CANADA MID/LATE NEXT
WEEK FROM SIBERIA.

CONFIDENCE...HIGH.

BEACHLER

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 09Z...

* DENSE FOG THROUGH THE MORNING...IMPROVING TO MVFR VSBY BY NOON.

* REDUCED VERTICAL VISIBILITIES OF 100 FT THROUGH MID MORNING
BECOMING 100 FT CIGS THROUGH NOON.

JEE

//DISCUSSION...UPDATED 09Z...
DENSE FOG HAS FINALLY ARRIVED AT ORD AND MDW LEADING TO SLIGHTLY
GREATER CONFIDENCE ABOUT THIS MORNINGS FORECAST. FOG HAS BECOME
THICKER VERTICALLY WHICH SHOULD MAKE IT HARDER TO MIX OUT IN THE
MORNING. WINDS STILL LOOK LIKE THEY WILL BE SLOW TO COME UP AND
THERE IS THE POSSIBILITY THAT AS THEY COME UP DENSE FOG COULD BE
ADVECTED INTO THE EASTERN TERMINALS THROUGH MID MORNING OR PERHAPS
LATER. GOING TO STAY WITH 06Z TAF TIMING AS FAR AS HOW QUICKLY
VSBY AND CIGS IMPROVE. ONE EXCEPTION IS AT RFD WHERE TIMING WAS
PUSHED AN HOUR BACK DUE TO THE THICKNESS OF THE FOG AND HOW LARGE
OF AN AREA IS COVERED BY DENSE FOG IN CENTRAL IL.

PREVIOUS DISCUSSION...06Z...
BROAD HIGH PRESSURE HAS SETTLED OVER THE REGION WITH WEAK TO CALM
WINDS. CLEAR SKIES HAVE ALLOWED FOR EFFICIENT RADIATIONAL COOLING
AND DENSE FOG DEVELOPMENT. MONITORING TWO AREAS OF DENSE FOG. THE
FIRST IS WEST OF A JVL TO RFD TO PIA LINE. THE SECOND IS EAST OF A
GYY TO IKK LINE. AT ITS CURRENT SPEED...THE WESTERN REGION OF
DENSE FOG WILL MOVE OVER ORD AND MDW BY 17Z. STATIONS UPSTREAM
HAVE SUDDENLY DROPPED FROM 2 SM TO 1/4 SM OR LESS AS THE AREA OF
DENSE FOG MOVES OVERHEAD. THINKING ORD AND MDW WILL NOT DROP TO
LESS THAN 1/4 SM. AS VSBY SETTLES IN ALSO EXPECTING VERTICAL
VISIBILITIES TO BE REDUCED TO 100 FT OR LESS.

SOUTHWEST FLOW WILL SLOWLY INCREASE TOMORROW MORNING...SLOWER THAN
PREVIOUSLY INDICATED. AS SUCH MOVED TIME OF MVFR VSBY IMPROVEMENT
BACK TO NOON. THE FOG WILL NOT DISSIPATE OR IMPROVE UNTIL BOUNDARY
LAYER MIXING GETS GOING. AS FOG MIXES OUT...EXPECTING IT TO RISE
RESULTING IN A PERIOD OF BKN001 CIGS MID WEDNESDAY MORNING THROUGH
ABOUT NOON. EXPECTING TO RETURN TO VFR BY MID WEDNESDAY AFTERNOON.

JEE

//ORD AND MDW CONFIDENCE...UPDATED 09Z...

* HIGH CONFIDENCE IN CIG VALUES.

* MEDIUM-HIGH CONFIDENCE IN VSBY...1/4SM LIKELY...M1/4SM PSBL.

* MEDIUM-HIGH CONFIDENCE OF TIMING OF VSBY/CIG IMPROVEMENT.

* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.

JEE

//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...

THURSDAY...GUSTY SOUTHERLY WINDS AND CHANCE OF SHRA...OTHERWISE
VFR.

FRIDAY...MVFR POSSIBLY EARLY...GUSTY NW WINDS...OTHERWISE VFR.

SATURDAY...VFR.

SUNDAY...VFR.

MONDAY...SLIGHT CHANCE SHRA...OTHERWISE VFR.

RODRIGUEZ

.MARINE...
343 AM CST

HIGH PRESSURE IS STRETCHED ACROSS THE MIDWEST THIS MORNING WITH
LIGHT SOUTHWEST WINDS ACROSS THE LAKE. THE HIGH WILL DRIFT EAST
TODAY WHILE THE NEXT LOW PRESSURE SYSTEM MOVES INTO THE NORTHERN
PLAINS. AS SUCH THE PRESSURE GRADIENT OVERHEAD WILL TIGHTEN WITH
WINDS BECOMING SOUTH AND INCREASING TO 30 KT. THE LOW PASSES TO THE
NORTH TOMORROW AND ITS COLD FRONT SLIDES THROUGH THURSDAY NIGHT.

FOR THE NEARSHORE WATERS...GOING WITH A SMALL CRAFT ADVISORY
BEGINNING THURSDAY MORNING FOR WINDS 20 TO 30 KT. GUIDANCE
INDICATES WINDS WILL DIMINISH TO BELOW 25 KT THURSDAY NIGHT AS THE
COLD FRONT MOVES THROUGH. WAVES WILL ALSO DIMINISH WITH THE FRONTAL
PASSAGE AND WESTERLY WIND SHIFT SO ENDED THE SMALL CRAFT THURSDAY
EVENING. HOWEVER EXPECTING WINDS TO INCREASE BACK TO AT LEAST 20
TO 30 KT AGAIN FRIDAY MORNING. SOME GUIDANCE MEMBERS INDICATE
GALES TO 35 KT MAY BE POSSIBLE...BUT THINKING TO 30 KT IS THE
BETTER BET RIGHT NOW. AS SUCH EXPECTING ANOTHER SMALL CRAFT
ADVISORY FOR FRIDAY MORNING THROUGH SATURDAY AFTERNOON/EVENING
DEPENDING HOW LONG IT TAKES THE WAVES TO SUBSIDE.

FOR THE OPEN WATERS...OCCASIONAL GALES ARE POSSIBLE OVER THE
NORTHERN HALF OF THE LAKE THURSDAY AS STRONG WARM AIR ADVECTION WILL
BE IN FULL SWING. THINKING THE AIR DIRECTLY ABOVE THE LAKE WILL BE
STABLE ENOUGH THAT A GALE HEADLINE WILL NOT BE NEEDED...HOWEVER A
FEW GALE GUSTS MAY REACH THE SURFACE. THE BETTER BET FOR GALES IS
BEHIND THE COLD FRONT BEGINNING THURSDAY NIGHT. GALES WILL BE
STRONGEST OVER THE NORTHERN HALF OF THE LAKE CLOSER TO THE LOW.
EXPECTING GALES TO DIMINISH QUICKLY FRIDAY NIGHT AS HIGH PRESSURE
APPROACHES FROM THE WEST. WINDS WILL BECOME WEAK WITH HIGH PRESSURE
OVER THE REGION SATURDAY NIGHT. ANOTHER LOW PRESSURE SYSTEM WITH
SOUTHWEST WINDS IS EXPECTED TO PASS NORTH OF THE AREA ON
SUNDAY...BUT GUIDANCE DIFFERS ON HOW STRONG THE LOW WILL DEEPEN AND
ITS PATH SO WENT WITH 15 TO 20 KT SOUTHWEST WINDS FOR NOW.

JEE

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...DENSE FOG ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 10 AM WEDNESDAY.

IN...DENSE FOG ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 10
AM WEDNESDAY.

LM...DENSE FOG ADVISORY...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-
LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-
LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-
LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 10 AM WEDNESDAY.

SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...9 AM THURSDAY TO 9 PM THURSDAY.

AREA FORECAST DISCUSSION

NWS LINCOLN IL

335 AM CST WED NOV 21 2012

.DISCUSSION...
ISSUED 315 AM CST WED NOV 21 2012
WEAK...BUT EXPANSIVE HIGH PRESSURE STRETCHING FROM THE SOUTHERN
PLAINS INTO THE NERN CONUS. LIGHT TO NON EXISTENT WINDS AND A POOL
OF LLVL MOISTURE BOTH LED TO A STUBBORN FOG BANK AND STRATUS DECK
PERSISTING THROUGHOUT MUCH OF THE DAY YESTERDAY IN IA. THIS
MORNING...THE FOG HAS SPREAD INTO ILLINOIS AND REDUCED
VISIBILITIES FOR THE MAJORITY OF THE STATE. AREAS IN THE SE ARE
RADIATING OUT RATHER EFFECTIVELY IN MOST LOCATIONS AND SOME VIS
ARE BEGINNING TO DROP AS WELL...IF NOT INTO DENSE FOG CAT. FIRST
ISSUE FOR THE FORECAST IS THE HANDLING OF THE FOG THIS
MORNING. ON THE OTHER SIDE OF THAT...THE FORECAST REMAINS THE
SAME...WITH CHANCE POPS ACCOMPANYING A SYSTEM PUSHING A FRONT
THROUGH THE MIDWEST ON THURSDAY...AND TEMPS ON THE BACKSIDE OF
THAT FRONT AS THE WARM AIR IS PUSHED BACK OUT OF THE MIDWEST.
ANOTHER SYSTEM COMING TOGETHER FOR THE FIRST PART OF THE WORK WEEK
AFTER THE HOLIDAY...WITH THE BETTER CHANCES FOR RAIN IN THE REGION
TO THE SOUTH ALONG THE OHIO RIVER VALLEY.

SHORT TERM...TODAY AND TONIGHT...
FOG IS A RATHER DIFFICULT FORECAST AS MODELS WERE NOT PICKING UP
ON THE STRATUS/FOG LAST NIGHT. A FORECAST OF PERSISTENCE WOULD
KEEP THE FOG AND CLOUDS OVER THE FA AT LEAST THROUGH MIDDAY. HAVE
EXPANDED AND EXTENDED THE DENSE FOG ADVISORY AS THE FORECAST
SOUNDINGS ARE NOT SHOWING MUCH IN THE WAY OF POTENTIAL FOR MIX OUT
UNTIL LATER IN THE DAY. TEMPERATURES GOING TO BE NEGATIVELY
IMPACTED FOR THE DAY AS THE LACK OF SUNSHINE AND MIXING GOING TO
PRECLUDE THE CHANCES TO GET UP INTO THE LOWER 60S. EXCEPTION WILL
BE ON THE EDGES OF THE STRATUS...TO THE EAST AND TO THE
SOUTH...WHERE SOME SUNSHINE MIGHT LAST MORE THAN A COUPLE HOURS
AND BOOST TEMPS A BIT HIGHER. IF THERES SUN...MIGHT GET INTO THE
UPPER 50S/LOWER 60S. WHERE THERES PERSISTENT CLOUDS AND
FOG...TEMPS WILL LIKELY STRUGGLE TO GET TO THE LOWER 50S.

LONG TERM...THURSDAY THROUGH TUESDAY...
LIGHT SOUTHERLY FLOW KICKS UP A NOTCH OR TWO TOMORROW...ASSISTING
IN WARMING THE REGION BACK UP AHEAD OF THE APPROACHING FRONT.
CLOUDS ALONG AND AHEAD OF THE FRONT WILL COUNTER THE LLVL
WAA...BUT MOS IS STILL PUSHING THE MAX TEMPS INTO THE LOW 60S.
FROPA IN THE OVERNIGHT HOURS WILL BRING THE BEST CHANCES FOR
WIDESPREAD PRECIP THU NIGHT. FRIDAY WILL START TO SEE COOLER
TEMPS...WITH DAYTIME HIGHS LOWER THAN THE PREVIOUS FEW NIGHTS
LOWS. FRIDAY WILL BE SOMEWHAT CHILLY WITH TEMPS IN THE 40S...BUT
SATURDAY WILL BE SIGNIFICANTLY COOLER WITH MAX TEMPS IN THE 30S AS
850 TEMPS DROP FROM ROUGHLY 10C ON WED AFTERNOON...TO -8C TO -10C
ON FRI NIGHT. TEMPS HAVE A CHANCE TO MODERATE SOMEWHAT FOR SUN AND
MON AS THE FLOW BECOMES QUASI ZONAL UNTIL ANOTHER SHOT OF
REINFORCING COLD AIR DROPS IN BEHIND A FRONT ON MON/MON NIGHT.
PRECIP ACCOMPANIES THE FRONT MON/MON NIGHT... AND BACK TO COOLER
TEMPS ON TUES.

HJS
&&

.AVIATION...
ISSUED 1124 PM CST TUE NOV 20 2012

PERSISTENT CLOUD COVER HAS BEEN SLOW TO CLEAR ACROSS EAST-CENTRAL
ILLINOIS THIS EVENING...HOWEVER SATELLITE LOOPS SUGGEST SKIES WILL
BE MOSTLY CLEAR AT ALL TERMINALS BY 06Z. MAIN AVIATION CONCERN
OVERNIGHT WILL BE THE DEVELOPMENT OF DENSE FOG. CURRENT
OBS/SATELLITE SHOW FOG DEVELOPING/EXPANDING EASTWARD ACROSS THE
ILLINOIS RIVER VALLEY TOWARD THE I-55 CORRIDOR. HRRR HAS HAD AN
EXCELLENT HANDLE ON THE FOG...AND SHOWS IT CONTINUING TO SPREAD
EASTWARD OVERNIGHT. STILL SOME UNCERTAINTY WHETHER DENSE FOG CAN
DEVELOP AS FAR EAST AS KCMI...SO HAVE ONLY REDUCED VISBYS THERE TO
AROUND 1SM AFTER 09Z. ELSEWHERE...HAVE BROUGHT VISBYS DOWN TO
1/4SM THROUGH 14Z. AFTER THAT...FOG WILL SLOWLY DISSIPATE
WEDNESDAY MORNING...WITH UNRESTRICTED VISBYS RETURNING AFTER 16Z.
AS HIGH PRESSURE AXIS SLIDES OFF TO THE EAST...WINDS WILL BECOME
S/SW AT 5 TO 10 KT WEDNESDAY AFTERNOON. 00Z NAM FORECAST SOUNDINGS
INDICATE THE POTENTIAL FOR MORE FOG WEDNESDAY NIGHT...HOWEVER
THINK SOUTHERLY FLOW ON THE BACK SIDE OF THE DEPARTING HIGH WILL
BE STRONG ENOUGH TO KEEP THE ATMOSPHERE SUFFICIENTLY MIXED.

BARNES
&&

.ILX WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR ILZ027>031-036>038-
040>057-061.

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

1131 PM CST TUE NOV 20 2012

.DISCUSSION...
922 PM CST

MTF

//PREV DISCUSSION...
628 PM CST

MTF

//PREV DISCUSSION...
256 PM CST

CONFIDENCE...HIGH.
CONFIDENCE ON AREAS OF DENSE FOG...MEDIUM/HIGH.

CONFIDENCE IN TEMPS...HIGH.
CONFIDENCE IN PRECIP...LOW.

CONFIDENCE...HIGH.

BEACHLER

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 06Z...

* DENSE FOG THROUGH THE MORNING...IMPROVING TO MVFR VSBY BY NOON.

* REDUCED VERTICAL VISIBILITIES OF 100 FT THROUGH MID MORNING
BECOMING 100 FT CIGS THROUGH NOON.

JEE

//DISCUSSION...UPDATED 06Z...

BROAD HIGH PRESSURE HAS SETTLED OVER THE REGION WITH WEAK TO CALM
WINDS. CLEAR SKIES HAVE ALLOWED FOR EFFICIENT RADIATIONAL COOLING
AND DENSE FOG DEVELOPMENT. MONITORING TWO AREAS OF DENSE FOG. THE
FIRST IS WEST OF A JVL TO RFD TO PIA LINE. THE SECOND IS EAST OF A
GYY TO IKK LINE. AT ITS CURRENT SPEED...THE WESTERN REGION OF
DENSE FOG WILL MOVE OVER ORD AND MDW BY 17Z. STATIONS UPSTREAM
HAVE SUDDENLY DROPPED FROM 2 SM TO 1/4 SM OR LESS AS THE AREA OF
DENSE FOG MOVES OVERHEAD. THINKING ORD AND MDW WILL NOT DROP TO
LESS THAN 1/4 SM. AS VSBY SETTLES IN ALSO EXPECTING VERTICAL
VISIBILITIES TO BE REDUCED TO 100 FT OR LESS.

JEE

//ORD AND MDW CONFIDENCE...UPDATED 06Z...

* HIGH CONFIDENCE IN CIG VALUES.

* MEDIUM-HIGH CONFIDENCE IN VSBY...1/4SM LIKELY...M1/4SM PSBL.

* MEDIUM-HIGH CONFIDENCE OF TIMING OF VSBY/CIG IMPROVEMENT.

* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.

JEE

//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...

THURSDAY...GUSTY SOUTHERLY WINDS AND CHANCE OF SHRA...OTHERWISE
VFR.

FRIDAY...MVFR POSSIBLY EARLY...GUSTY NW WINDS...OTHERWISE VFR.

SATURDAY...VFR.

SUNDAY...VFR.

MONDAY...SLIGHT CHANCE SHRA...OTHERWISE VFR.

RODRIGUEZ

.MARINE...
228 PM CST

A VERY WEAK GRADIENT IS IN PLACE ACROSS THE WESTERN GREAT LAKES
REGION THIS AFTERNOON RESULTING IN LIGHT AND VARIABLE WINDS ACROSS
LAKE MICHIGAN. AREAS OF FOG ARE EXPECTED ACROSS PORTIONS OF THE LAKE
TONIGHT INTO EARLY WEDNESDAY. WINDS SHOULD GRADUALLY MOVE TOWARDS A
SOUTHERLY DIRECTION OVERNIGHT AS LOW PRESSURE MOVES ACROSS THE
CANADIAN PRAIRIES AND OVER HUDSON BAY. THE GRADIENT TIGHTENS
PARTICULARLY ACROSS THE NORTHERN HALF OF THE LAKE WHERE WINDS WILL
INCREASE TO AROUND 30 KT BY WEDNESDAY EVENING. WEDNESDAY NIGHT INTO
THURSDAY...ANOTHER AREA OF LOW PRESSURE DEVELOPS OVER THE NORTHERN
PLAINS AND MOVES EAST TOWARDS LAKE SUPERIOR BY THURSDAY EVENING.
WINDS IN ADVANCE OF THIS SYSTEM WILL CONTINUE AROUND 30 KT THROUGH
THE DAY THURSDAY. AFTER A COLD FRONT SWEEPS ACROSS THE LAKE THURSDAY
NIGHT...STRONG COLD ADVECTION WILL ALLOW NORTHWEST WINDS TO INCREASE
TO GALES OF 35 TO 40 KT FRIDAY. RIDGING SHOULD MOVE ACROSS THE LAKE
EARLY IN THE WEEKEND ALLOWING WINDS TO DIMINISH...BUT BEYOND
SATURDAY...MODELS CONTINUE TO HAVE SIGNIFICANT DIFFERENCES LEADING
TO VERY LOW CONFIDENCE IN THE FORECAST LATE THIS WEEKEND INTO EARLY
NEXT WEEK. BMD

IN...DENSE FOG ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 10
AM WEDNESDAY.

AREA FORECAST DISCUSSION

NWS LINCOLN IL

1124 PM CST TUE NOV 20 2012

.DISCUSSION...
ISSUED 605 PM CST TUE NOV 20 2012

CLOUDS WILL CONTINUE TO SLOWLY CLEAR FROM NORTHWEST TO SOUTHEAST
THIS EVENING...WITH MOSTLY CLEAR SKIES EXPECTED ACROSS THE
BOARD AFTER MIDNIGHT. WITH CLEAR SKIES AND NEARLY CALM WINDS
BENEATH A SURFACE RIDGE AXIS...EXCELLENT RADIATIONAL COOLING
CONDITIONS WILL ALLOW SURFACE-BASED SATURATION TO OCCUR OVERNIGHT.
00Z/6PM IR SATELLITE IMAGERY SHOWS A PERSISTENT AREA OF DENSE FOG
ALONG THE MISSISSIPPI RIVER BEGINNING TO SLOWLY SPREAD EASTWARD.
20Z HRRR HAS AN EXCELLENT HANDLE ON THE FOG AREA...AND SHOWS IT
EXPANDING FURTHER EASTWARD INTO THE ILLINOIS RIVER VALLEY BETWEEN
03Z/9PM AND 06Z/12AM...THEN FURTHER EAST TO THE I-55 CORRIDOR
AFTER MIDNIGHT. HAVE THEREFORE ISSUED A DENSE FOG ADVISORY FOR ALL
LOCATIONS ALONG AND WEST OF A BLOOMINGTON-NORMAL TO TAYLORVILLE
LINE TONIGHT INTO WEDNESDAY MORNING. AM EXPECTING VISBYS TO DROP
TO LESS THAN 1/4 MILE AT TIMES...IMPACTING THE EARLY MORNING
COMMUTE. FURTHER EAST...FORECAST SOUNDINGS SHOW SLIGHTLY DRIER AIR
AT LOW-LEVELS...SUGGESTING FOG WITH VISBYS GENERALLY IN THE 1 TO 3
MILE RANGE TOWARD DAWN. UPDATED ZONE FORECAST HAS ALREADY BEEN
ISSUED.

BARNES
&&

.AVIATION...
ISSUED 1124 PM CST TUE NOV 20 2012

BARNES
&&

.PREV DISCUSSION...
ISSUED 307 PM CST TUE NOV 20 2012

MAIN CONCERNS THIS FORECAST PACKAGE INVOLVE PCPN CHANCES FOR
THURSDAY AND THURSDAY NIGHT WITH MILD TEMPS...AND CHC PCPN FOR
MONDAY THROUGH TUESDAY...ALONG WITH COOLER TEMPS THROUGH THE
EXTENDED PERIOD. MODELS REMAIN RELATIVELY SIMILAR IN THE SHORT
TERM BUT DIFFER SLIGHTLY WITH THE TIMING AND INTENSITY OF THE
SHORT WAVE COMING THROUGH THE AREA THUR AND THUR NIGHT...ALONG
WITH AMOUNT OF PCPN EXPECTED WITH THE FRONT. BELIEVE A BLEND OF
THE MODELS LOOKS BEST IN THE SHORT TERM. MODELS IN THE EXTENDED
PERIOD ALSO LOOK SIMILAR WITH DIFFERENCES BETWEEN THE ECMWF AND
THE GFS BEING WITH THE LOCATION AND STRENGTH OF A SFC LOW MOVING
NORTHEAST OUT OF THE SOUTHERN PLAINS EARLY NEXT WEEK.

SHORT TERM...TONIGHT THROUGH FRIDAY

HIGH PRSS WILL DRIFT ACROSS THE AREA TONIGHT...BRINGING VERY LIGHT
WINDS. DEWPOINTS HAVE INCREASED DURING THE DAY AND WITH AN
INVERSION EXPECTED TO SETUP THIS EVENING...DENSE FOG SEEMS
POSSIBLE. HOWEVER...MOST OF CWA HAS HAD LOTS OF SUNSHINE THIS
AFTERNOON AND BELIEVE THE SUN HAS BEEN ABLE TO BURN OFF SOME OF
THE LOW LEVEL MOISTURE. MODELS DIFFER ON WHAT RESULTING DEWPOINTS
WILL BE IN THE MORNING AS TEMPS FALL. BECAUSE OF SUNSHINE THIS
AFTERNOON AM NOT CONVINCED THAT DENSE FOG WILL OCCUR...BUT DO
THINK THERE WILL BE FOG OVERNIGHT. SO WILL HAVE AREAS OF FOG IN
THE FORECAST FOR OVERNIGHT AND MORNING HOURS TILL ABOUT 15Z. COULD
BE SOME ISOLATED/LOCALIZED AREAS WHERE FOG BECOMES DENSE...BUT NOT
ASSURED ENOUGH TO ADD TO FORECAST. WILL LET EVENING SHIFT EVALUATE.

AS HIGH PRSS MOVES TO THE SOUTHEAST TOMORROW...AM EXPECTING DRY
AND WARM WEATHER TOMORROW AND THURSDAY. THEN A FRONT WILL MOVE
INTO THE AREA LATE THURSDAY AND INTO THURSDAY NIGHT. BELIEVE
MOISTURE WILL STILL BE LIMITED BUT ENOUGH THAT PCPN CHANCES WILL
HAVE TO BE INCREASED FOR THURSDAY NIGHT. NAM IS DRY THROUGH THE
PERIOD...WHILE GFS HAS LOTS OF PCPN. SO WILL LIMITED POPS TO JUST
UNDER LIKELY GIVEN DIFFERENCES AND LIMIT MOISTURE EXPECTED. CLOUDS
AND PCPN MAY LINGER IN SOUTHEAST FRIDAY SO HAVE INCLUDED SLIGHT
CHC IN SOUTHEAST FOR FRI...MAINLY IN THE MORNING.

TEMPS WILL REMAIN ABOVE NORMAL FOR TWO MORE DAY AHEAD OF THE FRONT
BUT THEN FALL BEHIND THE FRONT. TEMPS FRIDAY EXPECTED TO BE IN THE
40S WITH AROUND 50 IN THE SOUTHEAST. THESE TEMPS WILL BE SLIGHTLY
BELOW NORMAL.

LONG TERM...FRIDAY NIGHT THROUGH TUESDAY

COOLER HIGH PRSS WILL BUILD INTO THE REGION FOR THE WEEKEND AND
TEMPS WILL BE COOLER THAN NORMAL THROUGH THE EXTENDED PERIOD.
ANOTHER FRONTAL SYSTEM WILL MOVE INTO THE AREA FOR BEGINNING OF
NEXT WEEK BUT MODELS DIFFER ON TIMING/POSITION/STRENGTH OF THE
FRONT/SYSTEM. HOWEVER...MODELS DO HAVE SOME PCPN FORECAST FOR MON
THROUGH TUE. SO REAL QUESTION WOULD BE PRECIP TYPE THROUGH THAT
TIME FRAME. BASED ON TRACK OF THE LOW PRSS AREA...MOST PCPN SHOULD
REMAIN ACROSS THE SOUTHERN TWO THIRDS OF THE CWA. WITH TEMPS
FALLING TO BELOW FREEZING AT NIGHT...WILL HAVE PCPN TYPE OF
RAIN OR SNOW AND THEN ALL SNOW OVER PARTS OF THE AREA. THIS COULD
CHANGE IF FURTHER NORTH TRACK FROM ECMWF FORECAST HOLDS TRUE
THROUGH REST OF THE WEEK. LOTS OF TIME TO WATCH AND SEE.

.ILX WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM CST WEDNESDAY FOR ILZ027>031-
036>038-040>043-047>053.

AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

929 AM EST WED NOV 21 2012

.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.

.SYNOPSIS...
ISSUED AT 302 AM EST WED NOV 21 2012

HIGH PRESSURE WILL REMAIN IN CONTROL UNTIL THURSDAY NIGHT...WHEN A
COLD FRONT IS EXPECTED TO PASS THROUGH THE AREA. IN THE WAKE OF
FRONT...HIGH PRESSURE WILL BUILD IN FOR THE WEEKEND. A LOW PRESSURE
SYSTEM MAY MOVE INTO THE AREA EARLY NEXT WEEK.

.NEAR TERM /TODAY/...

ISSUED AT 754 AM EST WED NOV 21 2012

HAVE EXPANDED THE DENSE FOG ADVISORY IN AREAL COVERAGE AND IN TIME
BASED ON RECENT SATELLITE TRENDS...OBS AND AREA WEBCAMS. THE MORE
WIDESPREAD FOG HAS EXPANDED INTO THE NORTHERN INDY METRO AND SHOULD
CONTINUE TO ADVANCE SOUTHEAST OVER THE NEXT HOUR OR TWO. RAP 975MB
RH PROGS SUGGEST THAT WIDESPREAD FOG SHOULD EXPAND SOUTH THROUGH THE
ENTIRE WABASH VALLEY TO VINCENNES AND ACROSS THE ENTIRE INDY METRO.
PERSISTENT DRY EASTERLY FLOW IN THE NEAR SURFACE LEVEL SHOULD KEEP
MORE WIDESPREAD FOG OUT OF THE SOUTHEAST COUNTIES BUT WILL NEED TO
MONITOR THROUGH THE MORNING.

ALSO EXTENDED THE ADVISORY OUT THROUGH 18Z WITH THE RIDGE AXIS ALOFT
NOT EXPECTED TO ARRIVE ACROSS THE REGION UNTIL THIS AFTERNOON. WIND
FLOW THROUGHOUT THE LOW LEVELS REMAINS LIGHT...AND POTENTIAL
CERTAINLY EXISTS THAT ADVISORY MAY NEED TO BE EXTENDED OUT EVEN
FURTHER IN TIME BASED ON COVERAGE AND EXTENT OF DENSE FOG BY MIDDAY.
ON TUESDAY...WIDESPREAD FOG/STRATUS THAT DEVELOPED ON THE LEE
SIDE OF THE UPPER RIDGE AXIS ACROSS EASTERN IOWA AND EXTREME WESTERN
ILLINOIS TOOK INTO THE MID AFTERNOON TO BREAK FOR MUCH OF THE AREA.

ZONE AND GRID UPDATES OUT. PREVIOUS DISCUSSION FOLLOWS.

IMMEDIATE CONCERN THIS MORNING WILL BE THE FOG. SATELLITE LOOPS
AND SURFACE OBSERVATIONS INDICATE AN AREA OF DENSE FOG OVER
NORTHEAST ILLINOIS AND NORTHWEST INDIANA HAS BEEN DRIFTING SOUTH
OVER THE PAST COUPLE OF HOURS. LEADING EDGE IS MOVING INTO THE FAR
NORTHWEST ZONES. PLANNING ON A DENSE FOG ADVISORY FOR SOME OF THE
NORTHWEST ZONES INTO THE LATE MORNING HOURS. UNCLEAR EXACTLY HOW FAR
SOUTH FOG BANK WILL GET THIS MORNING DUE TO SOME LINGERING CLOUD
COVER...BUT MAY NEED TO EXPAND IT FARTHER SOUTH IF CONDITIONS
WARRANT LATER THIS MORNING.

MODEL DATA SUGGEST NOCTURNAL INVERSION WILL BEGIN TO BREAK AFTER
211500Z...SO EXPECTING THE FOG TO BEGIN DISSIPATING BY THE LATE
MORNING HOURS. MIXING APPEARS LIMITED TODAY...SO IF THE FOG BECOMES
MORE WIDESPREAD THAN CURRENTLY THINKING...IT MAY LINGER LONGER INTO
THE DAY.

OTHERWISE...DRY WEATHER EXPECTED TODAY WITH HIGH PRESSURE IN
CONTROL. PROGGED LOW LEVEL THICKNESSES GENERALLY SUPPORT THE GFS MOS
HIGHS FOR TODAY. IF THE FOG HOLDS ON LONGER INTO THE DAY...THE HIGHS
WILL BE TOO WARM.

.SHORT TERM /TONIGHT THROUGH FRIDAY/...

ISSUED AT 302 AM EST WED NOV 21 2012

MODELS INDICATE THE MAIN ITEM OF INTEREST DURING THIS PERIOD WILL BE
THE UPPER TROUGH CURRENTLY MOVING INTO THE PACIFIC NORTHWEST. THIS
TROUGH IS EXPECTED TO MOVE EAST...PASSING THOUGH THE GREAT LAKES
AROUND FRIDAY. AN ASSOCIATED COLD FRONT IS EXPECTED TO MOVE THROUGH
THE LOCAL AREA THURSDAY NIGHT. APPEARS THERE IS A DECENT AMOUNT OF
LIFT ASSOCIATED WITH THE FRONT...HOWEVER MODELS SUGGEST THERE MAY BE
ONLY A RELATIVELY NARROW AREA OF NEAR SATURATION IN THE
PRECIPITATION BEARING LAYERS. BASED ON THE ABOVE...WILL KEEP POPS IN
THE CHANCE CATEGORY FOR NOW WITH RESPECT TO THIS EVENT. WILL GO WITH
SMALL CHANCE POPS OVER THE FAR NORTHWEST FOR LATE IN THE DAY
THURSDAY...AND CHANCE POPS ALL AREAS THURSDAY NIGHT.

MODELS SUGGEST THE LIFT/DEEPER MOISTURE WILL BE WELL OFF THE
SOUTHEAST BY SUNRISE FRIDAY...SO WILL TAKE OUT THE POPS FOR FRIDAY.

PROGGED LOW LEVEL THICKNESSES GENERALLY SUPPORT THE GFS MOS THROUGH
THE PERIOD...SO WILL NOT STRAY TOO FAR FROM THEM. ONLY EXCEPTION
WILL BE THE THURSDAY NIGHT LOWS. GIVEN THE STRONG COLD
ADVECTION...DECIDED TO TRIM A FEW DEGREES OFF OF THE GUIDANCE
LOWS...ESPECIALLY IN THE NORTHWEST.

.LONG TERM /SATURDAY THROUGH TUESDAY/...

ISSUED AT 330 AM EST WED NOV 21 2012

TEMPERATURES WILL BE QUITE COLD THIS WEEKEND...ESPECIALLY SATURDAY
AS A STRONG UPPER TROUGH OVER THE EASTERN GREAT LAKES MOVES
EASTWARD. HIGH PRESSURE OVER THE PLAINS AND MID MISSISSIPPI VALLEY
WILL MOVE EAST ACROSS OUR REGION OVER THE WEEKEND BRINGING DRY
WEATHER AND A SLIGHT MODERATION IN TEMPERATURES SUNDAY.

MODELS DIG ANOTHER UPPER TROUGH INTO THE NORTHERN PLAINS MONDAY AND
MOVE IT INTO THE GREAT LAKES TUESDAY. THEY ALSO DEVELOP A SURFACE
LOW OVER THE SOUTH CENTRAL PLAINS MONDAY AND TRACK IT ACROSS OUR
REGION TUESDAY.

MODELS THIS RUN HAVE TRENDED WARMER AND WILL ADJUST ADJUST
TEMPERATURES UP A LITTLE AND MOVE THE RAIN SNOW LINE NORTH AS WELL
MONDAY AND MONDAY NIGHT. AFTER THE LOW TRACKS BY EARLY
TUESDAY...THERE COULD BE FALLING TEMPERATURES LATER TUESDAY...BUT IT
IS TOO FAR OUT TO MENTION THAT AT THIS TIME.

ACCEPTED ALL BLEND TEMPERATURES AND POPS MOST PERIODS. ADDED A
LITTLE MORE GRADIENT IN TEMPERATURES MONDAY AND TUESDAY AS THERE
WILL BE A STRONG FRONT ACROSS OUR REGION.

.AVIATION /DISCUSSION FOR 15Z TAF UPDATE/...

ISSUED AT 929 AM EST WED NOV 21 2012

FOG AND LOWER VISIBILITIES CONTINUE TO IMPACT ALL TERMINALS AT
14Z...WITH GREATEST IMPACTS AT KHUF AND KLAF. ADJUSTED TIMING JUST A
BIT ON IMPROVEMENT OF VISIBILITIES...BUT OVERALL DO NOT EXPECT A
RETURN TO VFR CONDITIONS UNTIL 18Z OR BEYOND.

12Z DISCUSSION FOLLOWS.

SATELLITE INDICATES AREA OF FOG ACROSS ILLINOIS AND NORTHWEST
INDIANA HAS BEEN EXPANDING SOUTHEAST INTO CENTRAL INDIANA. EXPECT
CONDITIONS TO WORSEN THROUGH ABOUT 14-15Z ESPECIALLY AREAS NORTH AND
WEST OF KIND. KHUF AND KLAF WILL BE PREDOMINATELY LIFR WHILE KBMG
AND KIND LIFR OR IFR THROUGH ABOUT 16Z. AFTER THAT THERE SHOULD BE
SOME IMPROVEMENT WITH DAYTIME HEATING. KLAF MORE IN THE FOG AREA MAY
BREAK OUT LATER.

WILL GRADUALLY IMPROVE TAFS TO VFR BY MID AFTERNOON. HIGH PRESSURE
CURRENTLY ACROSS THE AREA WILL MOVE TO THE EAST. WINDS WILL BE
LIGHT THIS AFTERNOON AND BECOMING SOUTHERLY 5 KNOTS OR LESS
TONIGHT. SOME LIGHT FOG POSSIBLE TONIGHT. BUT INCREASING SOUTHERLY
GRADIENT SHOULD LIMIT FOG OVERNIGHT. WILL KEEP TAFS MOSTLY VFR FOR
NOW AFTER FOG CLEAR THIS AFTERNOON.

.IND WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
INZ021-028>031-035>049-051>055-060-061-067.

SYNOPSIS...JAS
NEAR TERM...JAS/RYAN
SHORT TERM...JAS
LONG TERM....JEH
AVIATION...JEH/RYAN

AREA FORECAST DISCUSSION...CORRECTED

NWS INDIANAPOLIS IN

754 AM EST WED NOV 21 2012

.UPDATE...
NEAR TERM SECTION HAS BEEN UPDATED BELOW.

.SYNOPSIS...
ISSUED AT 302 AM EST WED NOV 21 2012

.NEAR TERM /TODAY/...

ISSUED AT 754 AM EST WED NOV 21 2012

ZONE AND GRID UPDATES OUT. PREVIOUS DISCUSSION FOLLOWS.

.SHORT TERM /TONIGHT THROUGH FRIDAY/...

ISSUED AT 302 AM EST WED NOV 21 2012

MODELS SUGGEST THE LIFT/DEEPER MOISTURE WILL BE WELL OFF THE
SOUTHEAST BY SUNRISE FRIDAY...SO WILL TAKE OUT THE POPS FOR FRIDAY.

.LONG TERM /SATURDAY THROUGH TUESDAY/...

ISSUED AT 330 AM EST WED NOV 21 2012

ACCEPTED ALL BLEND TEMPERATURES AND POPS MOST PERIODS. ADDED A
LITTLE MORE GRADIENT IN TEMPERATURES MONDAY AND TUESDAY AS THERE
WILL BE A STRONG FRONT ACROSS OUR REGION.

.AVIATION /DISCUSSION FOR 12Z TAF ISSUANCE/...

ISSUED AT 600 AM EST WED NOV 21 2012

.IND WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
INZ021-028>031-035>049-051>055-060-061-067.

SYNOPSIS...JAS
NEAR TERM...JAS/RYAN
SHORT TERM...JAS
LONG TERM....JEH
AVIATION...JEH

AREA FORECAST DISCUSSION

NWS NORTHERN INDIANA

616 AM EST WED NOV 21 2012

.UPDATE/AVIATION...
EWD CREEP OF DEEPER FOG REFLECTED IN LATEST SAT IMAGERY THIS MORNING
W/PRIOR UPDATE CONCENTRATING ON SLIGHT EWD EXPANSION. THIS MAY YET
NEED TO BE CARRIED FURTHER INCLUDING FORT WAYNE AREA BUT FOR NOW IS
HOLDING. OTHERWISE 09Z RUC CONTS TREND SEEN IN 06Z RUN DEPICTING
STAUNCH LL THERMAL INVERSION HOLDING FOG/STRATUS IN PLACE UNTIL
EARLY AFTN AND SIMILAR IN SCOPE TO WHAT WAS OBSVD OVR ERN IA YDA
AFTN. THUS LAMP IMPLIED TREND OF HOLDING ONTO DENSE FOG UNTIL 17-18Z
LIKELY CORRECT.

KSBN WILL HOLD AT AIRPORT MINIMUMS THROUGH AT LEAST 16Z IF NOT A BIT
LONGER ESP IN LIGHT OF WIDESPREAD UPSTREAM STRETCH OF ZERO FOG
EXTENDING ALL THE WAY BACK TO ERN IA. KFWA HOLDING IN IFR CAT BUT
CONCEDE FURTHER DETERIORATION LIKELY TWD/AFT DAYBREAK AS NOCTURNAL
COOLING MAXIMIZES AND WILL TEMPO A FURTHER REDUCTION TO LIFR VSBYS
THROUGH MID MORNING W/12Z ISSUANCE.

.SHORT TERM...
DIFFICULT NR TERM PD DUE TO OVERNIGHT DVLPMNT OF WIDESPREAD
EXTREMELY DENSE FOG ACRS NW IN/SW MI WITHIN POST FNTL LK MSTR PLUME
AND RAPID CLRG ALOFT. ALTHOUGH FG LYR LOOKS THIN PER SAT OBS BELIEVE
LT NOV SUN AND WK BNDRY LYR MIXING/FLW WILL MAKE IT QUITE DIFFICULT TO
BURN OFF UNTIL LT MORNING-EARLY AFTN. THUS FEEL ITS PRUDENT TO SIGLY
UNDERCUT TEMPS IN THIS AREA.

OTHERWISE WK WAA DVLPG THROUGH AFTN AS FLW BACKS SWRLY AHD OF
IMPULSE EJECTING QUICKLY EWD OUT OF THE NEPAC. FAIRLY VIGOROUS HGT
FALLS ALOFT XPCD AS MID LVL TROF DEEPENS INTO THE WRN LAKES AND XPC
A COHESIVE AREA OF RAIN TO DVLP ALG SWWD TRAILING CDFNT THU NIGHT
AND BUMPED POPS TO HIGH CHC CWA WIDE. MUCH MORE VIGOROUS MIXING XPCD
WITHIN SHARP LL THERMAL RIDGE THU AFTN AND BUMPED TEMPS HIGHER IN
MOST AREAS.

.LONG TERM...FRIDAY THROUGH TUESDAY.

STRETCH OF ABOVE NORMAL TEMPS WILL BE COMING RAPIDLY TO AN END AS
COLD AIR INFILTRATES THE REGION BEHIND A STRONG COLD FRONT WHICH
WILL HAVE CLEARED THE FORECAST AREA BY LATE FRIDAY AFTERNOON. HIGH
TEMPS WILL OCCUR EARLY IN THE DAY WITH NON-DIURNAL TREND IN TEMPS
EXPECTED WITH FALLING READINGS THROUGH THE AFTERNOON. PRECIP
ASSOCIATED WITH THE FRONT LOOK TO DEPART JUST FAST ENOUGH TO KEEP
SNOW FROM MIXING FRIDAY MORNING...BUT COULD BE A CLOSE CALL. AS COLD
AIR SETTLES ACROSS THE LAKE AND ANOTHER WAVE DROPS SE...LAKE EFFECT
POTENTIAL WILL RAMP UP WITH SFC-850 MB DELTA T STILL PROGGED FOR 20
C OR GREATER WITH INVERSION HGTS AROUND 5-6 KFT. BUFKIT SOUNDINGS
FOR NAM12 FRIDAY NIGHT INDICATE LAKE INDUCED CAPE OVER 750 J/KG.
ALLBLEND JUST NOT ABLE TO CAPTURE LAKE EFFECT POTENTIAL WELL SO HAVE
KEPT WITH PREV SHIFT ALIGNMENT AND SLGT INCREASE IN POPS. NW FLOW
OF 20 KNOTS OR SO MAY ALLOW FOR DECENT INLAND PENETRATION OF LAKE
EFFECT SHOWERS WHICH MAY WARRANT EXPANDING BEYOND WHAT IS DEPICTED.

SATURDAY LOOKS TO BE A COOL...DAMP DAY WITH HIGHS LIKELY STRUGGLING
TO MOVE THROUGH THE 30S WITH LINGERING LAKE EFFECT CLOUDS IN NE
AREAS. SKIES WILL CLEAR OUT SATURDAY NIGHT INTO SUNDAY AS UPPER
LEVEL RIDGING BUILDS INTO THE AREA. TEMPS WILL HEAD BACK CLOSER TO
NORMAL. REST OF THE FORECAST REMAINS MUDDLED WITH MODELS INDICATING
LOW PRESSURE TAKING SHAPE IN THE PANHANDLE AREA OF TX/OK AND THEN
TRACK TOWARDS THE GREAT LAKES/OHIO VALLEY BY TUESDAY. NEW ECMWF RUN
BRINGS A MORE FAVORABLE SOUTHERN TRACK TO THE SFC LOW MOVING OVER
CLEVELAND TUES AFTERNOON. THIS WOULD PLACE THE NW AREAS INTO A MORE
FAVORABLE LOCATION FOR SNOW FALL WITH COLD AIR ESTABLISHED IN THESE
AREAS. SEVERAL DAYS REMAIN TO MONITOR TRENDS BUT POPS LEFT UNTOUCHED
TOWARDS THE END WITH RAIN/SNOW MENTION CONTINUED.

.AVIATION...
LT POST FNTL NW BNDRY LYR FLW AND RAPID CLRG HAD LED TO DENSE BUT
SHALLOW FG DVLPMNT ACRS NW IN/SW MI AND POSES CONSIDERABLE
UNCERTAINTY GOING FWD THROUGH LT MORNING IN TERMS OF PERVASIVENESS
AND EXTENT. GIVEN WK LL WAA ALOFT AND LIKELY POOR MIXING XPC LIFR
CONDS IN DENSE FOG TO CONT AT KSBN TERMINAL THROUGH AT LEAST MID
MORNING AND LIKELY LONGER W/GUIDANCE IMPLIED WK TO NON-EXISTENT
BNDRY LYR MIXING. DOWNSTREAM AREAS XPCD TO DUMP TO MVFR CONDS YET
LACK DEGREE OF LL MOISTENING HWVR LOW STRATUS MAY REDVLP INLINE
W/MODEL BASED RH CROSS SECTIONS AT KFWA AND WILL CONT TO MONITOR
CLOSELY THROUGH DAYBREAK.

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...DENSE FOG ADVISORY UNTIL NOON EST /11 AM CST/ TODAY FOR
INZ003>008-012>017-020-022>024.

MI...DENSE FOG ADVISORY UNTIL NOON EST TODAY FOR MIZ077>080.

OH...NONE.
LM...DENSE FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR LMZ043-046.

SMALL CRAFT ADVISORY FROM 10 AM THURSDAY TO 4 PM EST SATURDAY
FOR LMZ043-046.

SHORT TERM...T
LONG TERM...FISHER
UPDATE/AVIATION...T

AREA FORECAST DISCUSSION

NWS DES MOINES IA

902 PM CST THU NOV 22 2012

.UPDATE...
NO CHANGES TO WIND ADVISORY OVERNIGHT. ISOLATED SITES CONTINUE TO
HIT SUSTAINED AND GUST ADVISORY CRITERIA...30 AND 45 MPH
RESPECTIVELY. AIRMASS WILL REMAIN MIXED OVERNIGHT ESPECIALLY WITH
PASSAGE OF ANOTHER COLD ADVECTION MAX AFTER 06Z ASSOCIATED WITH
SECONDARY FRONT CURRENTLY DEPICTED FROM SD INTO MN. 01Z RAP 0-500M
LAYER WINDS REMAIN FAIRLY STEADY...BUT INCREASING SLIGHTLY 06Z-13Z.

.SHORT TERM /TONIGHT/...
A STRONG COLD FRONT IS PLOWING ACROSS IOWA FROM NORTHWEST TO
SOUTHEAST. THE WIND SHIFT HAS JUST PASSED THROUGH GRINNELL AND
CHARITON...AND WILL REACH OTTUMWA AND THE REST OF OUR SOUTHEASTERN
COUNTIES WITHIN THE NEXT COUPLE OF HOURS. HOWEVER...THE STRONGER
WINDS AND COLDER AIR ARE DELAYED A COUPLE OF COUNTIES BEHIND THE
WIND SHIFT...WITH TEMPERATURES ALREADY FALLING PRECIPITOUSLY ACROSS
OUR NORTHERN AREAS. LOW CLOUDS HAVE ALSO SPREAD INTO NORTHERN
IOWA...BUT FURTHER SOUTH SKIES ARE MOSTLY CLEAR.

THE AFOREMENTIONED TEMPERATURE...CLOUD...AND WIND FIELDS NECESSITATE
A PRE FIRST PERIOD IN THE AFTERNOON FORECAST ISSUANCE. WINDS SHOULD
DECREASE A LITTLE BIT WITH SUNSET AS MIXING DIMINISHES...HOWEVER
ANOTHER SHORTWAVE MOVING AROUND THE 500 MB LOW WILL TRANSLATE AT THE
SURFACE INTO AN EFFECTIVE REINFORCING COOL FRONT SWEEPING ACROSS THE
AREA OVERNIGHT. THIS FEATURE SHOULD ENTER OUR NORTHWEST A LITTLE
BEFORE MIDNIGHT AND CROSS THE AREA BEFORE SUNRISE...ACCOMPANIED BY A
SECOND WIND SURGE AND ADDITIONAL LOW CLOUDS. AT THIS TIME IT APPEARS
BASED ON FORECAST SOUNDINGS THAT THE STRATUS LAYER WILL BE FAIRLY
SHALLOW AND WITH NOT MUCH LIFT IN THE LAYER...SO HAVE LEFT FLURRIES
OUT OF THE FORECAST. OF GREATER CONCERN IS WHETHER OR NOT THE SECOND
WIND SURGE WILL ALLOW SPEEDS OR GUSTS TO REACH ADVISORY CRITERIA
OVERNIGHT. THERE APPEARS TO BE A GOOD POSSIBILITY OF THIS AND WITH
THE ADVISORY ALREADY IN EFFECT...HAVE OPTED NOT TO MAKE ANY CHANGES
TO THE HAZARD/HEADLINE AT THIS TIME. IN ANY EVENT WINDY CONDITIONS
WILL PERSIST THROUGH THE NIGHT AND INTO THE MORNING WITH RAPIDLY
FALLING TEMPERATURES AFTER SUNSET. WENT WITH A NON DIURNAL CURVE IN
AN ATTEMPT TO APPROXIMATE THE EFFECTS OF THE STRONG COLD AIR
ADVECTION BEHIND THE FRONT THIS EVENING AND WITH THE SECOND PUSH
OVERNIGHT.

.LONG TERM /FRIDAY THROUGH THURSDAY/...
LOW LEVEL COLD ADVECTION WILL CONTINUE TO PREVAIL ON FRIDAY LEADING
TO A COLD AND BLUSTERY DAY. HIGH TEMPERATURES WILL RANGE FROM THE
UPPER 20S NORTH TO THE MID TO UPPER 30S SOUTH. A WELL MIXED BOUNDARY
LAYER TO NEAR 875 MB WILL KEEP BREEZY TO GUSTY NORTHWEST WINDS IN
PLACE. THE WINDS COMBINED WITH THE TEMPERATURES WILL RESULT IN
APPARENT TEMPERATURE VALUES IN THE SINGLE DIGITS TO TEENS NORTH AND
TEENS TO MID 20S SOUTH. STRATUS DECK IS EXPECTED OVER THE NORTHEAST
TO BEGIN THE DAY BEFORE DIMINISHING THROUGH THE DAY. RIDGE OF HIGH
PRESSURE WILL MOVE INTO CENTRAL IOWA FRIDAY NIGHT WITH WINDS
DROPPING OFF. CLOUD COVER SHOULD INCREASE ACROSS THE WEST WITH MID
LEVEL THETA-E ADVECTION DEVELOPING. THE INCREASING MID LEVEL
TEMPERATURES WILL ENHANCE THE LOW LEVEL VERSION. THE STEEP INVERSION
AND DIMINISHING WINDS SHOULD LEAD TEMPERATURES WELL INTO THE TEENS.
CERTAINLY DEPENDENT ON CLOUDS AND HOW QUICKLY THEY MOVE IN. THE
STRONG LOW LEVEL INVERSION WILL CONTINUE ON SATURDAY AND WILL TEMPER
THE POTENTIAL FOR WARMING ON SATURDAY DESPITE RETURN SOUTHERLY FLOW.
HIGHS WILL RANGE FROM THE MID 30S TO LOWER 40S THE A LITTLE WARMER
ON SUNDAY.

A SHORT WAVE WILL DROP DOWN THROUGH THE NORTHWEST FLOW SUNDAY NIGHT
AND FOLLOWED BY ANOTHER MONDAY NIGHT AND TUESDAY. THIS WILL HELP
DRIVE COLDER AIR BACK INTO THE STATE. THE GEM REMAINS AN OVERLY
AGGRESSIVE OUTLIER DURING THE PERIOD COMBINING THE TWO WAVES AND
DEVELOPING A LOW PRESSURE SYSTEM THROUGH MISSOURI AND SOUTHERN
ILLINOIS WITH POTENTIAL OF MODERATE SNOWFALL THROUGH THE STATE.
STILL A VERY UNLIKELY SCENARIO WITH CANADIAN HIGH PRESSURE DROPPING
INTO THE UPPER MIDWEST AND SUPPRESSING THE SYSTEM WELL TO THE SOUTH.
POSSIBLE TO HAVE LIGHT RAIN OR SNOW WITH THE FRONTAL PASSAGE ON
MONDAY AND MONDAY NIGHT AND HAVE MAINTAINED LOW POPS. HIGH PRESSURE
WILL PREVAIL THROUGH THE REMAINDER OF THE EXTENDED WITH NEAR TO
BELOW CLIMATOLOGY TEMPERATURES AND NO PRECIPITATION EXPECTED.

.AVIATION...23/00Z
MVFR STRATUS HAS ADVANCED DOWN TO KSHL-KSLB-KFOD-KIFA-KFXY LINE AT
2330Z AND WILL CONTINUE TO AFFECT MUCH OF NRN IA INTO FRI MORNING.
CIGS ARE EXPECTED TO DIP BELOW 2KFT AT KMCW AS WELL. ALTHOUGH GUSTY
NW WINDS WILL DIMINISH SLIGHTLY EARLY THIS EVENING...SECONDARY PUSH
OF COLD AIR AND MIXING WILL BOOST GUSTS ONCE AGAIN 06Z-09Z WITH
GUSTS WELL INTO THE 30S NORTH. MVFR CIGS SHOULD EXIT BY LATE FRI
MORNING FOLLOWED BY VERY GRADUALLY DECREASING WINDS INTO THE
AFTERNOON...AND EVENTUALLY DECOUPLING INTO SUNSET.

.DMX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY THROUGH 6 AM CST FRIDAY FOR CALHOUN-CERRO GORDO-EMMET-
HANCOCK-HUMBOLDT-KOSSUTH-PALO ALTO-POCAHONTAS-SAC-WEBSTER-WINNEBAGO-
WORTH-WRIGHT

UPDATE/AVIATION...SMALL
SHORT TERM...LEE
LONG TERM...DONAVON

AREA FORECAST DISCUSSION

NWS DES MOINES IA

1141 PM CST TUE NOV 20 2012

.UPDATE...
VIS/FOG SATELLITE IMAGERY SHOWS LOW STRATUS AND FOG HAS ENTERED
FORECAST AREA FROM THE EAST WITH OBS INDICATING VISIBILITIES QUICKLY
DROPPING TO NEAR ZERO ONCE IT BEGINS. HAVE ONLY INCLUDED TWO TIERS
OF ERN COUNTIES FOR A START EXPECTING WESTWARD PROGRESSION TO
EVENTUALLY CEASE WHERE IT ENCOUNTERS DRIER AIRMASS. LATEST RAP
1000-950MB RH DROPS QUICKLY TO AROUND 50 PERCENT ALONG THE I35
CORRIDOR.

.SHORT TERM /TONIGHT/...
SFC HIGH CENTERED FROM SRN IA SOUTHWESTWARD TO SLIDE EAST SOUTHEAST
TONIGHT...WITH SOUTHERLY FLOW AND WAA KICKING IN ALOFT. MOSTLY CLEAR
SKIES EXPECTED TONIGHT WITH THE EXCEPTION OF THE FAR EAST...WHERE
LOW STRATUS/FOG THAT IS CURRENTLY ACROSS SOUTHEASTERN IOWA EXPECTED
TO BUILD BACK WEST/NORTHWARD THIS EVENING. THEREFORE LOW CLOUDS/FOG
POSSIBLE FROM WATERLOO TO MARSHALLTOWN TO OTTUMWA OVERNIGHT...BASED
ON THE HRRR OUTPUT FOR LOW CLOUDS. AS SFC RIDGE AXIS PUSHES THROUGH
THE AREA AND WAA/SOUTHERLY FLOW INCREASES EXPECT MIN TEMPS TO START
LEVELING OFF/POSSIBLY WARMING TOWARD SUNRISE.

.LONG TERM /WEDNESDAY THROUGH TUESDAY/...
HIGH PRESSURE WILL SHIFT OFF TO THE SOUTHEAST ON WEDNESDAY AS A
BROAD AREA OF HIGH PRESSURE MOVES INTO THE DAKOTAS. THIS WILL
INCREASE THE SOUTHERLY FLOW INTO IOWA AS THE THERMAL RIDGE LEANS
INTO THE STATE. THESE CONDITIONS ALONG WITH VERY DRY AIR WILL BE
CONDUCIVE TO GOOD WARMING. AN INVERSION NEAR 900 MB APPEARS TO BE A
LIMITING FACTOR FROM ACHIEVING RECORD HIGH TEMPERATURES IN THE LOWER
70S HOWEVER EVEN IF THE INVERSION HOLDS...SUPER ADIABATIC LAPSE NEAR
SURFACE SHOULD PUSH READINGS INTO THE MID TO UPPER 60S. THE THERMAL
RIDGE STRENGTHENS WEDNESDAY NIGHT WITH SOUTHERLY WINDS CONTINUING.
LOWS WILL BE WELL INTO THE 40S AT MOST LOCATIONS. THURSDAY WILL HAVE
A WARM START WITH A COLD FRONT EXPECTED TO PASS THROUGH CENTRAL IOWA
DURING THE AFTERNOON. AN SHORT WAVE WILL LIFT UP THROUGH THE
SOUTHWEST FLOW AHEAD OF THE BOUNDARY AND WILL BRING THE CHANCE FOR A
FEW SHOWERS OVER THE FAR SOUTHEAST. THE NMM AND ARW BASED MODELS ARE
FARTHER SOUTHEAST WITH THIS SYSTEM THOUGH THE ECMWF AND GFS AFFECT
IOWA MORE. GENERALLY ANY PRECIPITATION WILL BE LIGHT. THIS SYSTEM
COULD BRING AN INCREASE IN CLOUDS AND MAY LIMIT TEMPERATURES A BIT.
CENTRAL AND SOUTHEAST IOWA SHOULD REACH THE 60S BEFORE THE COLD
FRONT PASSES THROUGH. STRONGER COLD ADVECTION NEAR 850 MB WILL
ENHANCE MIXING BEHIND THE FRONTAL BOUNDARY WITH INCREASING
SUBSIDENCE AIDING MOMENTUM TRANSFER OF WINDS TO THE SURFACE. MIXED
LAYER WINDS OF 25 TO 35 KTS SHOULD PUSH SUSTAINED WINDS TO NEAR WIND
ADVISORY CRITERIA MAINLY OVER THE NORTH AND WEST.

ANOTHER SURGE OF COLD ADVECTION WILL DROP SOUTH THURSDAY NIGHT.
FRIDAY WILL BE BLUSTERY AND COLD WITH BREEZY NORTHWEST WINDS. HIGHS
WILL GENERALLY BE IN THE LOW TO MID 30S. HIGH PRESSURE MOVES ACROSS
FRIDAY NIGHT. CURRENTLY HAVE LOWS A FEW DEGREES ABOVE MOS GUIDANCE
FOR POTENTIAL MID TO HIGH LEVEL CLOUDS WITH INCREASING THETA-E
ADVECTION THROUGH THOSE LEVELS. MINOR MODERATION SATURDAY INTO
SUNDAY. A STRONGER COLD FRONT IS DUE TO ARRIVE MONDAY AND LEAD TO A
COLD START TO NEXT WEEK. THE EXTENDED WILL BE MOSTLY DRY WITH THE
POTENTIAL FOR VERY LIGHT RAIN OR SNOW EARLY NEXT WEEK.

.AVIATION...21/06Z
LIFR STRATUS AND FOG IS CURRENT ALONG AND EAST OF AN KALO-KOOA-KOTM
LINE AND HAS MOVED LITTLE RECENTLY. CIRRUS MOVING ACROSS FORECAST
AREA HAS DECREASE RATE OF SURFACE COOLING. 21Z HRRR IS DEPICTING
REALITY QUITE WELL AND ONLY SPREADS LIFR A BIT FARTHER WESTWARD
OVERNIGHT. KEPT IT OUT OF KDSM AND KMCW FOR THE TIME WITH 04Z RAP
SHOWING LOWER 50MB RH IN THESE AREAS. CONDITIONS WILL LIKELY EITHER
BE VFR OR LIFR WITH LITTLE IN BETWEEN. REGARDLESS EXPECT VFR
RETURNING TO ALL SITES BY 15-16Z WED AS SLY WINDS CONTINUE TO
GRADUALLY INCREASE WITH MIXING.

.DMX WATCHES/WARNINGS/ADVISORIES...DENSE FOG ADVISORY UNTIL 900 AM
BUTLER-BREMER-GRUNDY-BLACK HAWK-MARSHALL-TAMA-JASPER-POWESHIEK-
MARION-MAHASKA-MONROE-WAPELLO-APPANOOSE-DAVIS

SHORT TERM...MJB
LONG TERM...DONAVON
AVIATION...SMALL

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

345 PM CST WED NOV 21 2012

...UPDATED SYNOPSIS AND SHORT TERM SECTIONS...

.SYNOPSIS...
ISSUED AT 343 PM CST WED NOV 21 2012

THE PERSISTENT LONGWAVE TROUGH CONTINUED TO BE THE PREVAILING
METEOROLOGICAL FEATURE ACROSS THE PACIFIC-NORTH AMERICA SECTOR. ON
THE SYNOPTIC SCALE, A FAIRLY INTENSE STORM SYSTEM WAS MOVING INLAND
WASHINGTON/SOUTHERN BRITISH COLUMBIA. BY WEDNESDAY AFTERNOON, THE
PRIMARY CIRCULATION CENTER WAS MOVING ACROSS THE CANADIAN ROCKIES.
THE STRONG CROSS-MOUNTAIN FLOW WAS KEEPING MSLP FAIRLY LOW ACROSS
ALL OF THE NORTHERN HIGH PLAINS (1001MB SURFACE LOW NEAR ALZADA,
MONTANA AT 21Z). A SUBSTANTIAL WARM SECTOR ENCOMPASSED MUCH OF THE
GREAT PLAINS FROM TEXAS TO SOUTH DAKOTA WITH WIDESPREAD 70S OBSERVED
THIS AFTERNOON. MSLP GRADIENT WAS STRONGEST FROM WESTERN IOWA INTO
SOUTHWESTERN KANSAS WHERE WINDS RANGED FROM 22 TO 27 KNOTS SUSTAINED
DURING THE AFTERNOON HOURS. OF NOTE AS WELL (WHICH WILL PLAY INTO
TONIGHTS FORECAST), WAS A SUBTROPICAL DISTURBANCE FROM NEW MEXICO TO
SOUTHWEST TEXAS WHICH YIELDED QUITE A BIT OF MID AND HIGH LEVEL
CLOUD COVER AND EVEN A FEW LIGHTNING STRIKES FROM SHOWERS AND
ISOLATED THUNDERSTORMS.

.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 343 PM CST WED NOV 21 2012

FOR THE TIME PERIOD TONIGHT AND TOMORROW, THE GREATEST CHALLENGE IN
THE FORECAST WILL BE LOWS TONIGHT AND HOW MUCH CLOUD COVER AND WIND
WILL INFLUENCE OVERNIGHT TEMPERATURES. THE PREVIOUS FORECAST
ALREADY HAD A FAIRLY TIGHT GRADIENT IN LOW TEMPERATURES TONIGHT
(FROM 33F ACROSS FAR WEST CENTRAL KANSAS TO AROUND 51F ACROSS FAR
SOUTH CENTRAL KANSAS). THESE LOOK GOOD FOR THE MOST PART, BUT THE
LATEST RAP AND NAM12 MODELS SUGGEST TEMPERATURES WILL NOT GET MUCH
BELOW 60F SOUTHEAST OF A GREAT BEND TO ASHLAND LINE, AND GIVEN THE
SEMI OPAQUE SKY COVER FROM 300-500MB CLOUD (FROM THE SUBTROPICAL
SHORTWAVE TROUGH) AND THE SOUTHWEST WINDS CONTINUING 12 TO 16 KNOTS
IN THESE AREAS, REALLY CANNOT ARGUE AGAINST THESE WARM TEMPERATURES
TONIGHT. AS A RESULT, I HAVE BUMPED UP MIN TEMPS ABOUT 2 TO 4
DEGREES AND MOVED THE GRADIENT WESTWARD ABOUT 30 MILES OR SO
(EFFECTIVELY WARMING UP DODGE CITY LOW QUITE A BIT).

THE FORECAST FOR THANKSGIVING DAY WILL BE A LITTLE LESS COMPLICATED
AS MID-HIGH LEVEL CLOUD COVER WILL BE MOVING EAST OF THE AREA WITH
SURFACE WINDS BECOMING NORTHWESTERLY. WHILE COLD ADVECTION WILL
EXIST BEHIND THE FRONT, THE AIRMASS WILL BE MODIFIED BY DOWNSLOPE
AND INSOLATION WILL ALSO COUNTER THE COLD ADVECTION. HIGHS WILL
STILL BE ABOVE AVERAGE FOR THE DATE WITH TEMPERATURES WARMING INTO
THE 60S (LOWER 70S SOUTH CENTRAL KS). WITH THE INITIAL ISALLOBARIC
WIND SURGE/PRESSURE RISE WITH THE PASSAGE OF THE FRONT, WIND SPEEDS
WILL BE 22 TO 26 KNOTS MUCH LIKE TODAY, BUT THESE SPEEDS SHOULD ONLY
OCCUR DURING ABOUT A 3 OR 4 HOUR PERIOD BEFORE WINDS GRADUALLY
DECREASE BACK DOWN TO THE 18 TO 22 KT RANGE LATE IN THE DAY.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 248 PM CST WED NOV 21 2012

BY THE BEGINNING OF THE EXTENDED PERIOD ON THURSDAY NIGHT, A STRONG
UPPER LEVEL SHORTWAVE TROUGH WILL BE MOVING OUT OF THE NORTHERN
PLAINS INTO THE MIDWESTERN STATES AND GREAT LAKES REGION. A COLD
FRONT WILL BE LOCATED OVER SOUTHEAST KANSAS INTO WEST TEXAS. HIGH
PRESSURE WILL BE BUILDING INTO WESTERN KANSAS BEHIND THE FRONT
THURSDAY NIGHT THROUGH FRIDAY. THE 12Z MODEL TEMPERATURE FORECASTS
ARE COMING IN COOLER THAN PREVIOUS RUNS WHICH SEEMS REASONABLE GIVEN
THE ONGOING COLD AIR ADVECTION.

INTO THIS WEEKEND, FLAT UPPER LEVEL RIDGING WILL SPREAD EAST ACROSS
THE WESTERN AND CENTRAL PART OF THE COUNTRY. ANOTHER SHORTWAVE
TROUGH WILL MOVE INTO THE PACIFIC NORTHWEST ON SATURDAY BEHIND THE
RIDGE AND THIS FEATURE WILL BE DIGGING SOME AS IT MOVES INTO THE
CENTRAL HIGH PLAINS BY MONDAY NIGHT. THROUGH THIS WEEKEND THE DRY
FORECAST WILL CONTINUE WITH TEMPERATURES WILL MODERATE BACK INTO THE
60S. LEE SIDE TROUGHING WILL DEVELOP ON SATURDAY. THIS WILL DEVELOP
INTO A LOW PRESSURE AREA THAT MOVES INTO THE OKLAHOMA AND TEXAS
PANHANDLES BY SUNDAY EVENING AS THE NEXT UPPER TROUGH APPROACHES.
THIS WILL BRING A SWITCH IN THE SURFACE WINDS BACK AROUND TO THE
EAST TO NORTHEAST ON SUNDAY. THIS WAVE WILL MOVE OUT ACROSS THE
CENTRAL AND NORTHERN PLAINS MONDAY NIGHT. THERE DOES NOT APPEAR TO
BE SUFFICIENT MOISTURE AVAILABLE FOR THIS SYSTEM TO WORK WITH. THE
BEST CHANCES FOR MEASURABLE PRECIPITATION WILL BE ALONG THE EASTERN
SLOPES OF THE ROCKIES AND OVER EASTERN KANSAS INTO THE MID
MISSISSIPPI VALLEY. HIGH TEMPERATURES WILL DROP BACK INTO THE 40S ON
MONDAY AND TUESDAY.

THE REMAINDER OF THE EXTENDED PERIOD WILL SEE AN UPPER LEVEL RIDGE
BUILDING OVER THE CENTRAL PART OF THE COUNTRY. THIS WILL RESULT IN
TEMPERATURES MODERATING BACK INTO THE 60S LATER NEXT WEEK.

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1254 PM CST WED NOV 21 2012

STRONG SOUTHWEST WINDS OF 20 TO 25 KNOTS WILL CONTINUE THROUGH
SUNSET, AT WHICH POINT A DECREASE TO TO AROUND 15 KNOTS IS
EXPECTED. DURING THE OVERNIGHT HOURS...THERE WILL BE A GRADUAL
WIND SHIFT TO THE WEST THEN NORTHWEST WITH SPEEDS AROUND 6 TO 9
KNOTS. A COLD FRONT WILL MOVE ACROSS WESTERN KANSAS EARLY
THURSDAY WHICH WILL RESULT IN AN INCREASE IN WIND SPEEDS ONCE
AGAIN AFTER 15Z...TO THE 22-25 KNOT RANGE BY MIDDAY.

.PRELIMINARY POINT TEMPS/POPS...
DDC 53 66 24 53 / 0 0 0 0
GCK 36 64 22 53 / 0 0 0 0
EHA 39 65 23 53 / 0 0 0 0
LBL 48 67 24 55 / 0 0 0 0
HYS 43 63 21 51 / 0 0 0 0
P28 56 72 28 53 / 10 10 0 0

.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SYNOPSIS...UMSCHEID
SHORT TERM...UMSCHEID
LONG TERM...GERARD
AVIATION...UMSCHEID

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

438 PM EST WED NOV 21 2012

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 437 PM EST WED NOV 21 2012

12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR RDG EXTENDING
NEWD FM THE SRN PLAINS INTO THE GRT LKS BTWN A TROF ALONG THE E
COAST AND ANOTHER ALONG THE W COAST. THE AIRMASS ALOFT IS QUITE WARM
AND DRY OVER THE UPR GRT LKS...BUT LO CLDS ENHANCED BY RADIATIONAL
COOLING LAST NGT THAT FORMED UNDER SHARP LLVL INVRN SHOWN ON LOCAL
12Z RAOBS ARE PROVING TO BE QUITE RESILIENT OVER THE SCENTRAL AND
ERN CWA WITH ADDED MOISTENING OFF LK MI IN SSW FLOW BTWN HI PRES IN
THE MID ATLANTIC AND LOWER PRES IN THE PLAINS. THERE IS NO FOG/ST
NOTED TO THE W...BUT PLENTY OF HI CLDS ARE STREAMING ENEWD FM THE
PLAINS INTO THE UPR LKS IN THE WSW FLOW ALF. A POTENT SHRTWV IS
COMING ASHORE IN THE PAC NW.

LATE THIS AFTN...LO CLDS PRESENT EARLY THIS AFTN OVER THE SCENTRAL
AND E WILL BREAK UP THRU THE AFTN IN THE PRESENCE OF SOME DIURNAL
HEATING. THESE CLDS WL BE MOST RESILIENT OVER THE FAR E DOWNWIND OF
LK MI AS STLT IMAGERY SHOWS ST DECK EXTENDING ALMOST THE ENTIRE
LENGTH OF THE LK.

TNGT...ALTHOUGH THE ST SHOULD BE GONE THIS EVNG EXCEPT OVER THE FAR
E...SUSPECT THIS LO CLD WL FORM AGAIN TNGT WITH NOCTURNAL COOLING
AND PERSISTENT SSW FLOW/LO INVRN SHOWN ON FCST SDNGS. CONFIDENCE IN
THIS SCENARIO IS HIER SINCE THE 12Z NAM/LOCAL WRF-ARW SHOW HIER
H95-9 SPECIFIC HUMIDITY ADVECTING INTO THE AREA OVERNGT IN THE
STRENGTHENING LLVL SSW FLOW. H925 WINDS AS HI AS 30-40KTS BY LATE
TNGT SHOULD LIMIT THE POTENTIAL FOR DENSER FOG...BUT STILL ADDED
SOME PATCHY FOG OVER THE SCENTRAL AND E AWAY FM MORE PRONOUNCED
DOWNSLOPE WARMING OVER THE NW AND NCENTRAL AS MODELS HINT AT A
PERIOD OF LIGHTER WINDS THIS EVNG THAT MIGHT AUGMENT A PERIOD OF
QUICK COOLING. MIN TEMPS WL REMAIN WELL ABV NORMAL WITH INCRSG
WINDS/ QUITE A BIT OF HI CLD...ESPECIALLY IN THE DOWNSLOPE AREAS
OVER THE W AND NCENTRAL NEAR LK SUP.

THANKSGIVING DAY...WITH DIURNAL HEATING...EXPECT LO CLDS/FOG IN THE
MRNG TO BREAK UP BY NOON. BUT WITH PERSISTENT SSW FLOW...THE ST WL
MOST LIKELY LINGER LONGER INTO THE AFTN OVER THE E DOWNSTREAM OF LK
MI. ATTENTION THEN TURNS TO TIMING/IMPACT OF SHRTWV NOW MOVING INTO
THE PAC NW. MODELS SHOW THIS DISTURBANCE MOVING EWD TO OVER MN BY
00Z FRI. ALTHOUGH ASSOCIATED SFC LO PRES IS FCST TO MOVE INTO
ONTARIO JUST N OF LK SUP WITH ATTENDANT COLD FNT PROGGED TO REACH
CENTRAL UPR MI BY 00Z...DEEP LARGER SCALE FORCING IS FCST TO HANG TO
THE W THRU THAT TIME. WITH LINGERING MID LVL DRY AIR...ANY
ACCOMPANYING PCPN SHOULD PUSH NO FARTHER THAN WRN LK SUP UNTIL AFT
00Z. OTRW... LOOK FOR ANOTHER DAY OF WELL ABV NORMAL TEMPS UNDER H85
THERMAL RDG UP TO 11C RIGHT AHEAD OF THE FNT. BUT TEMPS OVER THE W
SHOULD FALL IN THE AFTN FOLLOWING THE COLD FROPA WITH H85 TEMPS
PROGGED TO TUMBLE TOWARD 0C AT IWD BY 00Z FRI.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 437 PM EST WED NOV 21 2012

MODEL HAVE COME INTO MUCH BETTER OVERALL AGREEMENT RELATING TO THE
SYSTEM THAT WILL BRING SNOW TO MUCH OF THE AREA THU NIGHT INTO
SAT...WITH MAINLY SMALLER SCALE/TIMING DIFFERENCES THAT ARE NOT OUT
OF THE NORM FOR THE TIME FRAME OF THE EVENT. A GENERAL MODEL
CONSENSUS WAS USED...WITH MOST FORECAST ALIGNMENT WITH THE 12Z/21
NAM/GFS AND TO A SOMEWHAT LESSER DEGREE THE 00Z/21 ECMWF

FOCUSED MAJORITY OF ATTENTION ON THE SYSTEM THU NIGHT INTO SAT GIVEN
HIGHER IMPACTS FROM POST THANKSGIVING TRAVEL/ACTIVITIES.

AT 00Z FRI...MODELS SHOW THE 500MB SHORTWAVE IN THE BEGINNING STAGES
OF BEING CLOSED OFF OVER NW MN WITH A 1000MB SFC LOW OVER CENTRAL
LAKE SUPERIOR...AND A SFC COLD FRONT FROM THE HURON MOUNTAINS TO
IRON OR DICKINSON COUNTY. 850MB TEMPS WILL BE JUST FALLING BELOW 0C
OVER FAR WRN UPPER MI...BUT WILL STILL BY AROUND 6C OVER THE ERN
CWA. THE MID LEVEL LOW WILL CONTINUE TO STRENGTHEN AS IT MOVES TO
THE CENTRAL CWA BY 12Z FRI /AVG LOCATION AMONG PREFERRED
MODELS...THERE WERE MINOR TIMING DIFFERENCES/...WITH HEIGHT FALLS OF
7-10DAM FROM 12 HOURS PREVIOUS. BY 12Z FRI THE BULK OF THE SFC LOW
WILL HAVE SHIFTED NE INTO ONTARIO...BUT PREFER THE NAM/GEM/ECMWF
SOLUTIONS THAT PIN A 998MB SFC LOW OVER NE LAKE SUPERIOR AS OFTEN
HAPPENS DUE TO THE WARM LAKE TEMPS. 850MB TEMPS FALL TO -10C TO -12C
OVER WRN LAKE SUPERIOR BY 12Z FRI...AND WILL WELL BELOW 0C OVER THE
REST OF THE CWA. THE COMBINATION OF THE DEEPENING SFC LOW...COLD AIR
OVER THE WARM LAKE AND SHARP PRESSURE GRADIENT LEAD TO STRONG WINDS.
THE STRONGEST WINDS LOOK TO BE OVER THE KEWEENAW AND NEAR LAKE
SUPERIOR E OF THE HURON MOUNTAINS...ESPECIALLY ALONG THE SHORELINES
OF ALGER AND LUCE COUNTIES. IN THESE AREAS...MODELS SHOW 925MB WINDS
IN EXCESS OF 40KTS...SO GUSTS AS HIGH AS 40KTS SEEM APPROPRIATE FOR
THE FORECAST IN THESE MORE EXPOSED LOCATIONS FROM THE NW WINDS LATE
THU NIGHT AND THROUGH MUCH OF FRI. A SHORT SWATH OF DRY LOW AND MID
LEVEL AIR ROTATES THROUGH THE WRN CWA LATE FRI MORNING...WHICH WILL
DIMINISH SNOWFALL TO SOME EXTENT. MODELS THEN INDICATE ANOTHER
SHORTWAVE PUSHING THROUGH SOMETIME SAT EVENING AS 850MB TEMPS FALL
TO -14C OVER MUCH OF LAKE SUPERIOR...WHICH WILL ACT TO ENHANCE
SNOWFALL RATES. AFTER THIS SHORTWAVE...SNOWFALL SHOULD GENERALLY
SLOWLY DIMINISH IN INTENSITY/COVERAGE UNTIL SFC AND UPPER RIDGING
MOVES IN FROM THE W SAT...REACHING IWD BY 18Z SAT AND THE FAR ERN
CWA AROUND 00Z SUN.

GIVEN HOW QUICKLY TEMPS GET COLD AS THE UPPER LOW IS MOVING
OVER...SNOW TO LIQUID RATIOS WILL JUMP UP PRETTY QUICKLY TO AROUND
18 TO 1 RATIOS. THIS WILL INCREASE SNOWFALL ACCUMULATIONS AND WILL
ALLOW THE SNOW TO BE BLOW AROUND MORE FROM GUSTY WINDS. EXPECT TWO
MAIN BURSTS OF SNOW THAT SHOULD BE ESPECIALLY UNTACTFUL...ONE AS THE
UPPER LOW PUSHES IN WITH LAKE ENHANCEMENT ADDING TO SNOW INTENSITY.
THIS WILL HAPPEN THU NIGHT INTO EARLY FRI MORNING OVER THE WRN
CWA...AND FRI MORNING TO AROUND NOON FRI OVER THE ERN CWA. THE
SECOND BURST LOOKS TO BE WITH THE SECOND SHORTWAVE FRI EVENING TO
EARLY SAT NIGHT WITH ENHANCEMENT OF THE LES. THE FIRST BURST OF SNOW
LOOKS TO BE THE WORST GIVEN THE INCREASED FORCING FROM THE 500MB
LOW...WHICH WILL ALSO BE AT THE WORST TIMES GIVEN MUCH INCREASED
POST THANKSGIVING TRAVEL/ACTIVITY AS FAR A SOCIETAL IMPACTS GO. THIS
IS COMPOUNDED BY THE FACT THAT NO SIGNIFICANT SNOWFALL HAS OCCURRED
IN A WHILE...WHICH LOCAL STUDIES SUGGEST LEADS TO A LARGE INCREASE
IN TRAFFIC ACCIDENTS ONCE SNOW DOES FALL.

AS FAR AS SNOWFALL AMOUNTS GO...HAVE HIGHEST CONFIDENCE IN SNOWFALL
AMOUNTS OF PORTIONS OF ALGER...LUCE AND NRN SCHOOLCRAFT COUNTIES
WHERE MOISTURE WILL LINGER LONGER AND THE FETCH ACROSS LAKE SUPERIOR
WILL BE BETTER AND NW WINDS WILL NOT CHANGE DIRECTIONS MUCH THROUGH
THE EVENT. OVER THESE ERN AREAS...THE NAM SHOWS STORM TOTAL QPF
/WHICH SHOULD BE ALMOST ALL SNOW/ OF JUST UNDER 0.80 INCHES...WHICH
MAY BE A BIT ON THE HIGH SIDE BUT CAN NOT BE RULED OUT.
OVERALL...THINK 6-10 INCHES /WITH SOME POTENTIAL FOR UP TO A FOOT/
TOTAL SNOWFALL SEEMS REASONABLE FOR THE ERN AREAS. LOWEST CONFIDENCE
IS OVER THE NRN HURON MOUNTAINS IN NW MARQUETTE AND NE BARAGA
COUNTIES...AS THIS AREA IS ALWAYS HARD TO FORECAST IN NW WINDS...BUT
WOULD THINK 3-5 INCHES STORM TOTAL SNOW IS REASONABLE. THE HIGHER
TERRAIN OF WRN UPPER MI FROM IWD TO CMX AND COPPER HARBOR SHOULD SEE
4-8 INCHES STORM TOTAL SNOW /HIGHEST OVER PORTION OF NRN HOUGHTON
COUNTY AND WRN ONTONAGON/NRN GOGEBIC COUNTIES/...BUT WITH MORE
UNCERTAINTY THAT THE ERN CWA AND MORE HIGHER POSSIBILITIES OF HIGHER
OR LOWER AMOUNTS. NCENTRAL PARTS OF THE CWA /GENERALLY IN THE
MARQUETTE-NEGAUNEE AREA/ LOOK TO SEE 1-3 INCHES OF SNOW THROUGH THE
ENTIRE PERIOD. SCENTRAL PORTIONS OF THE CWA SHOULD SEE LITTLE TO NO
SNOW.

HEADLINES FOR THIS EVENT ARE SOMEWHAT TRICKY IN THAT TRADITIONAL
SNOWFALL AMOUNT BASED CRITERIA WILL NEED TO BE RELAXED GIVEN A
VARIETY OF PREVIOUSLY DISCUSSED SOCIETAL IMPACTS AND OTHER
CONTRIBUTING FACTORS /SUCH AS GUSTY WINDS/. GIVEN HIGHER CONFIDENCE
OVER THE ERN CWA /ALGER...LUCE AND NRN SCHOOLCRAFT COUNTIES/ DECIDED
TO ISSUE A WINTER STORM WATCH FOR THESE AREAS. ELSEWHERE ALONG THE
LAKE SUPERIOR SHORE...ISSUED AN SPS HIGHLIGHTING POOR TRAVEL
CONDITIONS SINCE IT IS TOO FAR OUT FOR AN ADVISORY.

NEXT SYSTEM OF INTEREST MOVES OVERHEAD ON SAT NIGHT INTO EARLY SUN
AS A CLIPPER SYSTEM PUSHES THROUGH. BEST MOISTURE IS CO-LOCATED WITH
UPPER SUPPORT IN LEFT EXIT REGION OF UPPER JET OVER NRN PORTIONS OF
THE AREA. INCREASED CONSENSUS GUIDANCE TO MID RANGE CHANCE POPS. AT
THIS TIME A COUPLE OF INCHES OF SNOW APPEARS POSSIBLE...MAINLY IN
THE HIGHER TERRAIN OVER THE NRN CWA.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1226 PM EST WED NOV 21 2012

EXPECT VFR CONDITIONS TO PREDOMINATE AT ALL 3 SITES INTO THIS EVNG.
BUT WITH RADIATIONAL COOLING TNGT...EXPECT SOME FOG AND LO CLDS/IFR
CONDITIONS TO DEVELOP AT SAW. WITH INCRSG SSW WINDS OVERNGT ABOVE
RADIATION INVRN...LLWS WL DVLP AT ALL 3 LOCATIONS. DOWNSLOPE NATURE
OF THIS SSW FLOW SHOULD LIMIT THE POTENTIAL FOR LO CLDS/FOG AT CMX
AND IWD. DAYTIME HEATING/MIXING SHOULD END LLWS/DISSIPATE ANY LO
CLDS AND FOG BY LATE THU MRNG.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 437 PM EST WED NOV 21 2012

EXPECT S WINDS UP TO 20 KTS THRU THIS EVENING TO INCREASE UP TO 25
KTS LATE TONIGHT AND THU UNDER TIGHTENING PRES GRADIENT AHEAD OF
COLD FRONT ASSOCIATED WITH POWERFUL DISTURBANCE MOVING ACROSS THE
NORTHERN CONUS. ONCE THE COLD FRONT MOVES WEST TO EAST THU AFTERNOON
AND NIGHT...EXPECT A SHARP WIND SHIFT TO THE NW. AS THE PRES
GRADIENT TIGHTENS CONSIDERABLY AND MUCH COLDER AIR MOVES OVER THE
UPPER LAKES...EXPECT A HI END GALE EVENT EXCEPT OVER THE FAR W WITH
THE COLDER AIR ENHANCING THE MIXING OF STRONGER WINDS ALOFT TO THE
LAKE SURFACE. GIVEN THE CONSISTENT FORECAST TIMING AND STRENGTH OF
THIS EVENT...OPTED TO UPGRADE GOING GALE WATCHES TO WARNINGS FOR THE
LATE THU NIGHT INTO FRI NIGHT PERIOD. SOME STORM FORCE WIND GUSTS
WILL ALSO BE POSSIBLE ON FRI...ESPECIALLY OVER THE E HALF OF THE
LAKE. THE APPROACH OF A HI PRES RIDGE LATE FRI NIGHT WILL CAUSE THE
GALES TO DIMINISH W-E THEN. ANOTHER LO PRES TROF WILL IMPACT THE
UPPER GREAT LAKES OVER THE WEEKEND...BUT A WEAKER PRES GRADIENT WILL
LIKELY HOLDS WINDS TO NO HIER THAN 25 KTS.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM LATE THURSDAY NIGHT THROUGH LATE FRIDAY
NIGHT FOR MIZ006-007-085.

LAKE SUPERIOR...
GALE WARNING FROM 1 AM FRIDAY TO 1 AM EST SATURDAY FOR
LSZ264>267.

GALE WARNING FROM 1 AM TO 7 PM EST FRIDAY FOR LSZ263.

LAKE MICHIGAN...
NONE.
&&

SHORT TERM...KC
LONG TERM...TITUS
AVIATION...KC
MARINE...KC

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

1227 PM EST WED NOV 21 2012

.UPDATE...
ISSUED AT 1052 AM EST WED NOV 21 2012

LO CLDS ARE PROVING TO BE QUITE RESILIENT OVER THE E HALF OF THE CWA
WITH SSW FLOW OFF LK MI ENHANCING THE MOISTENING UNDER SHARP LLVL
INVRN DEPICTED ON THE 12Z GRB/APX RAOBS. TENDED TO HOLD ON TO FOG
FOR A COUPLE HRS LONGER AND LOWERED MAX TEMPS A COUPLE OF DEGREES
WHERE THE ST WL LINGER LONGEST.
&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 608 AM EST WED NOV 21 2012

WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL RIDGE
FROM THE SOUTHERN AND CENTRAL PLAINS INTO THE WESTERN GREAT LAKES
AND A TROUGH FROM THE GULF OF ALASKA INTO THE PACIFIC NORTHWEST. A
VIGOROUS SHORTWAVE TROUGH WAS MOVING ONSHORE INTO OR AND SOUTHERN
WA. AT THE SURFACE...SOUTHERLY FLOW WAS INCREASING BETWEEN HIGH PRES
BUILDING INTO THE EASTERN GREAT LAKES AND A TROUGH FROM NW ONTARIO
INTO EASTERN NORTH DAKOTA.

WITH ABUNDANT LOW LEVEL MOISTURE OVER THE AREA...DEWPOINTS INTO THE
MID AND UPPER 30S...AREAS OF DENSE FOG HAVE DEVELOPED OVER INTERIOR
PORTIONS OF CENTRAL UPPER MICHIGAN AND OVER THE HIGHER TERRAIN OF
THE KEWEENAW. INCREASING WINDS AND DRY ADVECTION HAS HELPED REDUCE
FOG COVERAGE/DENSITY.

TODAY...EXPECT ANY LINGERING FOG TO DISSIPATE EARLY WITH THE DRY
ADVECTION FROM THE WEST AND THE ONSET OF DAYTIME HEATING LEAVING
CLEARING SKIES. WAA WILL PUSH 850 MB TEMPERATURES ARE EXPECTED TO
REACH TO AROUND 10C...HOWEVER THE WEAK NOVEMBER SUNSHINE WILL LIMIT
TEMPERATURES TO THE MID TO UPPER 50S...WITH THE WARMER TEMPERATURES
OVER THE DOWNSLOPE LOCATIONS FAVORED BY A SOUTHERLY WIND. SOUTHERLY
WINDS WILL CONTINUE TO INCREASE OVER THE REGION AS THE PRESSURE
GRADIENT INCREASES BETWEEN LOW PRESSURE APPROACHING FROM THE
NORTHWEST AND THE HIGH TO THE SOUTHEAST.

TONIGHT...LOW PRES WILL MOVE TO NORTH OF KINL KEEPING BREEZY SOUTH
WINDS GOING. SO...LOW TEMPS WILL NOT FALL OF MUCH WITH MIN READINGS
ONLY IN THE LOWER TO MID 40S. THIS COULD AGAIN RESULT IN RECORD HIGH
LOW MINS FOR MANY LOCATIONS. THE WIND AND MIXING SHOULD ALSO
MINIMIZE POTENTIAL FOR FOG FORMATION EVEN THOUGH DEWPOINTS REMAIN
AROUND 40.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 608 AM EST WED NOV 21 2012

THANKSGIVING WILL MARK THE LAST DAY OF UNSEASONABLY WARM WEATHER FOR
AWHILE AS A SW FLOW CONTINUES TO BRING WARM AIR OVER THE GREAT LAKES
REGION AHEAD OF A FAST-APPROACHING STRONG SHORTWAVE MOVING IN FM THE
NRN PLAINS. DESPITE INCREASING WAA CLOUDS IN THE AFTERNOON AHEAD OF
THE INCOMING SHORTWAVE...MIXING TO JUST 900 MB AS INDICATED ON NAM
FCST SNDGS WOULD EASILY YIELD HIGH TEMPS IN THE MID 50S ACROSS MUCH
OF THE AREA. UPPER 50S COULD EVEN BE REACHED FOR WEST HALF LOCATIONS
ALONG LAKE SUPERIOR IN DOWNSLOPE SSW FLOW. RECORD TEMP OF 54F ON THE
22ND MAY BE IN JEOPARDY AT THE MQT NWS OFFICE. TEMPS WILL STAY A BIT
COOLER (LOW 50S) ALONG LAKE MICHIGAN SHORE IN SSW FLOW. INCREASING
MID-LVL MOISTURE AND DPVA TOWARD EVENING COULD BRING IN SOME ISOLD
SHRA LATE INTO THE WESTERN CWA SO HAVE KEPT IN SLIGHT CHC
POPS.

THURSDAY NIGHT AND FRIDAY...FOLLOWED ALONG NCEP PREFERRED BLEND OF
00Z GFS AND ECMWF WHICH ADVERTISES A SLOWER AND MORE AMPLIFIED SOLN
WITH THE NRN PLAINS SHORTWAVE AND ASSOC FRONTAL SYSTEM THAN THE NAM
OR THE CANADIAN MODELS. THE GFS AND ECMWF BLENDED SOLN ALSO HAS
SUPPORT FM THE 00Z UKMET RUN. COMPROMISE SOLN WOULD TAKE
SHORTWAVE/5H CLOSED LOW ACROSS NRN WI/CENTRAL UPR MI WITH WINDS
SHIFTING FROM WEST BEHIND INITIAL COLD FROPA IN THE EVENING TO THE
NORTHWEST OVERNIGHT BEHIND PASSAGE OF MAIN SHORTWAVE/5H TROUGH AND
SECONDARY COLD FRONT. IT IS BEHIND THIS SECONDARY COLD FRONT AND
ADVECTION OF -10 TO -12C 8H AIR OVER WRN LAKE SUPERIOR THAT LAKE
EFFECT PCPN WL QUICKLY CHANGEOVER TO SNOW LATE THU NIGHT INTO EARLY
FRIDAY. THERE COULD ALSO BE SEVERAL HOUR PERIOD OF ENHANCEMENT AS
SHORTWAVE AND ASSOC DEEP LYR Q-VECT CONV SPREADS QUICKLY ACROSS THE
AREA. ENHANCEMENT WILL BE LOST BY LATE FRI AFTERNOON AS SHORTWAVE
EXITS EAST OF THE AREA AND EVENT WILL TRANSITION TO PURE LAKE EFFECT
SNOW AS 8H TEMPS LOWER TO AROUND -15C.

FRIDAY NIGHT INTO SATURDAY...THERE MAY BE A BRIEF PERIOD FOR
ADDITIONAL ENHANCEMENT TO SNOW FRI EVENING WITH MODELS HINTING AT
ANOTHER WEAK CLIPPER SHORTWAVE MOVING ACROSS THE AREA BUT AFTER THAT
MODELS ARE IN GOOD AGREEMENT WITH STRONG RDG BUILDING IN FM NW OF
LAKE SUPERIOR. STRONG SUBSIDENCE ASSOC WITH THIS RDG WILL SHARPLY
LOWER INVERSION HGTS TO BLO 4KFT OVER THE WEST BY 12Z SAT WHICH
SHOULD QUICKLY DIMINISH LES TO FLURRIES EARLY SATURDAY. LONGER FETCH
IN NW FLOW ACROSS ERN LAKE SUPERIOR WILL ALLOW SOME LES TO
ACCUMULATE INTO SAT MORNING BUT THEN STRONG SUBSIDENCE AND DRYING
SHOULD DIMINISH ANY REMAINING LES TO FLURRIES BY AFTERNOON.

TOTAL SNOW ACCUMULATION DURING THE EVENT FM THU NIGHT INTO EARLY
SATURDAY WILL LIKELY REACH 3-7 INCHES WITH THE HIGHEST AMOUNTS OVER
HIGHER NW FACING TERRAIN OF WRN AND ERN SECTIONS OF THE CWA DOWNWIND
OF LAKE SUPERIOR. AN ADVISORY HEADLINE MAY EVENTUALLY BE NEEDED
DURING THIS TIME FRAME BUT FOR NOW WILL CONTINUE WORDING OF SEVERAL
INCHES OF ACCUMULATING SNOW IN THE HWO.

SUNDAY THROUGH TUESDAY...MODELS IN GENERAL AGREEMENT WITH A
TRANSITION TOWARD A MORE ZONAL FLOW PATTERN FOR EARLY NEXT WEEK. A
WEAK WNW FLOW SHORTWAVE MOVING THROUGH SAT NIGHT INTO SUNDAY COULD
BRING SOME LIGHT SNOW TO MAINLY THE NRN AND ERN PORTIONS OF THE CWA.
A WEAK N-NE FLOW SETTING UP FOR MON INTO TUE BTWN HIGH PRESSURE OVER
SCNTRL CANADA/NRN PLAINS AND LOW PRESSURE DVLPG OVER THE SRN/CENTRAL
PLAINS WILL CONTINUE TO WARRANT LOW CHC POPS FOR LIGHT LES WITH 8H
TEMPS LINGERING AROUND -14C.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1226 PM EST WED NOV 21 2012

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 608 AM EST WED NOV 21 2012

WINDS SHOULD REMAIN BELOW 20 KNOTS THROUGH THURSDAY MORNING AS HIGH
PRESSURE REMAINS IN CONTROL OF THE REGION. WINDS WILL SHIFT FROM THE
SOUTH THURSDAY AFTERNOON TO THE NORTHWEST AND INCREASE TO GALES TO
35 KNOTS BY FRIDAY MORNING AS THE PRESSURE GRADIENT INCREASES ACROSS
THE AREA. GALES ARE ARE EXPECTED TO DIMINISH BY FRIDAY EVENING OVER
WESTERN LAKE SUPERIOR AND OVER THE EAST LATE FRIDAY NIGHT. WINDS
SHOULD REMAIN BELOW 20 KNOTS FROM SATURDAY AFTERNOON THROUGH THE
REMAINDER OF THE PERIOD.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM LATE THURSDAY NIGHT THROUGH LATE FRIDAY NIGHT
FOR LSZ264>267.

GALE WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY EVENING FOR
LSZ263.

LAKE MICHIGAN...
NONE.
&&

UPDATE...KC
SHORT TERM...JLB
LONG TERM...VOSS
AVIATION...KC
MARINE...JLB

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

1053 AM EST WED NOV 21 2012

.UPDATE...
ISSUED AT 1052 AM EST WED NOV 21 2012

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 608 AM EST WED NOV 21 2012

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 608 AM EST WED NOV 21 2012

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 711 AM EST WED NOV 21 2012

VLIFG STATUS AND FOG AT CMX AND SAW IS EXPECTED LIFT TO VFR
CONDITIONS BY MID TO LATE MORNING WITH THE ONSET OF DAYTIME HEATING
AND AS DRIER AIR MOVES IN FROM THE WEST. OTHERWISE...VFR CONDITIONS
SHOULD PREVAIL INTO THIS EVENING. AN INCREASING SW LOW LEVEL JET
THIS EVENING WILL RESULT IN LOW LEVEL WIND SHEAR. THE STRONGER WINDS
SHOULD PROVIDE ENOUGH MIXING TO REDUCE THREAT FOR ADDITIONAL FOG
FORMATION. HOWEVER...THERE MAY BE ENOUGH UPSLOPE COMPONENT WITH SRLY
SFC WINDS FOR MVFR BR AT SAW. ALTHOUGH IFR CONDITIONS CANNOT BE
RULET OUT...CONFIDENCE WAS LOWR THAT ANY LOWER STRATUS DECK OR
THICKER FOG WOULD DEVELOP.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 608 AM EST WED NOV 21 2012

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM LATE THURSDAY NIGHT THROUGH LATE FRIDAY NIGHT
FOR LSZ264>267.

GALE WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY EVENING FOR
LSZ263.

LAKE MICHIGAN...
NONE.
&&

UPDATE...KC
SHORT TERM...JLB
LONG TERM...VOSS
AVIATION...JLB
MARINE...JLB

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

714 AM EST WED NOV 21 2012

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 608 AM EST WED NOV 21 2012

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 608 AM EST WED NOV 21 2012

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 711 AM EST WED NOV 21 2012

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 608 AM EST WED NOV 21 2012

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
DENSE FOG ADVISORY UNTIL 8 AM EST /7 AM CST/ THIS MORNING FOR
MIZ001-003>005-010>013-084.

LAKE SUPERIOR...
GALE WATCH FROM LATE THURSDAY NIGHT THROUGH LATE FRIDAY NIGHT
FOR LSZ264>267.

GALE WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY EVENING FOR
LSZ263.

LAKE MICHIGAN...
NONE.
&&

SHORT TERM...JLB
LONG TERM...VOSS
AVIATION...JLB
MARINE...JLB

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

610 AM EST WED NOV 21 2012

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 608 AM EST WED NOV 21 2012

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 608 AM EST WED NOV 21 2012

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1234 AM EST WED NOV 21 2012

TOUGH FORECAST OVERNIGHT FOR ALL TAF SITES AND CONFIDENCE IS LOW.
LOW LEVEL MOISTURE IS TRAPPED UNDER AN INVERSION AND THIS IS CAUSING
FOG WITH LOW VIS AND LOW CLOUDS. KIWD IS ON EDGE OF THIS AND HAS
MANAGED TO DOWNSLOPE THE FOG AND STRATUS OUT AND EXPECT THAT TO
CONTINUE OVERNIGHT. CMX AND SAW WILL CONTINUE WITH LOWER VIS AND FOG
OVERNIGHT. THIS MIXES OUT IN THE MORNING AND VFR CONDITIONS WILL
THEN CONTINUE. UPSLOPE FOG AND STRATUS WILL DEVELOP AGAIN WED
EVENING FOR SAW FROM LAKE MICHIGAN. LLWS IS ALSO POSSIBLE WED
EVENING AT SAW AND IWD.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 608 AM EST WED NOV 21 2012

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
DENSE FOG ADVISORY UNTIL 8 AM EST /7 AM CST/ THIS MORNING FOR
MIZ001-003>005-010>013-084.

LAKE SUPERIOR...
GALE WATCH FROM LATE THURSDAY NIGHT THROUGH LATE FRIDAY NIGHT
FOR LSZ264>267.

GALE WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY EVENING FOR
LSZ263.

LAKE MICHIGAN...
NONE.
&&

SHORT TERM...JLB
LONG TERM...VOSS
AVIATION...07
MARINE...JLB

AREA FORECAST DISCUSSION...UPDATED

NWS TWIN CITIES/CHANHASSEN MN

610 PM CST THU NOV 22 2012

.AVIATION.../18Z TAF ISSUANCE/

LIGHT...TO AT TIMES MODERATE SNOW HAS BEEN FALLING FOR THE PAST
FEW HOURS GENERALLY NEAR AND NORTHEAST OF AXN/STC/MSP/RNH.
SATELLITE INDICATES THE ENHANCED CLOUD TOPS HAVE BEEN PIVOTING
NORTHEAST ACROSS SRN MN...BUT HAVE BEEN SLOWING AND COULD STALL
THIS EVENING JUST SOUTH OF AXN/STC AND SOMEWHERE IN THE VICINITY
OF MSP AS ANOTHER DISTURBANCE OVER NCTRL SD TRACKS SOUTHEAST.
THUS...EXPECT ANOTHER SEVERAL HOURS OF LIGHT SNOW AT THESE TAF
SITES WITH VIS IN THE 1-3 MILE RANGE AT TIMES. COULD SEE SOME OF
THIS SNOW REACH EAU AS WELL BY 02Z.

OTHERWISE...MVFR CIGS TO CONTINUE INTO FRIDAY MORNING BEFORE
LIFTING AND SCATTERING OUT BY AFTERNOON. NORTHWEST WINDS WILL
REMAIN STRONG THROUGH FRIDAY MORNING WITH GUSTS BETTER THAN 30
KNOTS OCCASIONALLY.

KMSP...LIGHT SNOW CONTINUES TO FALL WITH THE BACK EDGE OF THE
STEADY SNOW 40SM WEST OF THE TERMINAL. GIVEN SATELLITE TRENDS...IT
APPEARS THIS BACK EDGE WILL SLOW SOME AS IT APPROACHES SO KEPT
MVFR VIS UNTIL 02Z. THEREAFTER...THERE MAY BE A BREAK FOR A FEW
HOURS BEFORE ANOTHER BATCH OF LIGHT SNOW ARRIVES OVERNIGHT. MVFR
CIGS WILL PERSIST UNTIL LATE FRIDAY MORNING BEFORE SCATTERING OUT
FOR AFTERNOON AND EVENING. WINDS WILL REMAIN STRONG TONIGHT...THEN
GRADUALLY SUBSIDE FRIDAY.

/OUTLOOK FOR KMSP/
SAT...VFR. WINDS S AT 5-10KTS.
SUN...VFR. WINDS WNW AT 5-10KTS.
MON...MAINLY VFR...POSSIBLE MVFR CIGS LATE WITH -SN. WINDS N 5 KTS.

.PREV DISCUSSION...
/ISSUED 222 PM CST THU NOV 22 2012/

THERE IS ABOUT A 30 DEGREE DIFFERENCE IN THE TEMPERATURE EARLY
THIS AFTERNOON ACROSS THE CWA FROM WEST TO EAST. THE STRONG COLD
FRONT IS NEAR A RICE LAKE-MENOMINEE LINE AND WILL BE EAST OF OUR
CWA BY 22Z. IN THE WAKE OF THE FRONT...NORTHWEST WINDS OF 20 TO 25
MPH WITH GUSTS WELL INTO THE 30 MPH RANGE ARE COMMON. A BAND OF RAIN
AND SNOW EXISTS AS WELL BEHIND THE FRONT FROM SOUTHWEST MN THROUGH
CENTRAL AREAS OF THE STATE AND INTO THE ARROWHEAD. THIS IS AHEAD
OF AN AXIS OF MID LEVEL FRONTOGENESIS ALONG WITH A SUBSTANTIAL PV
BOOT AIMED AT KDLH. WEB CAMS THIS AFTERNOON HAVE INDICATED A QUICK
COATING OF SNOW AS THE BAND MOVES THROUGH.

OUR LOCAL WRF AND THE HRRR HAVE A PRETTY GOOD HANDLE ON THE
PRECIPITATION PATTERN. THE BAND OF FRONTOGENESIS WILL MOVE THROUGH
THE EASTERN MN...INCLUDING THE TWIN CITIES...IN THE 21Z-24Z TIME
FRAME AND ACROSS WEST CENTRAL WI IN THE 00Z-03Z PERIOD. OUR WRF
AND THE HRRR SUGGEST THE BEST CHANCES FOR PRECIPITATION DURING THE
LATE AFTERNOON AND EARLY EVENING HOURS ARE FROM THE NORTH METRO ON
NORTH AND EAST. THIS IS WHERE LIKELY POPS EXIST FOR A TIME WITH
DIMINISHING POPS TO THE SOUTH. A QUICK HALF INCH OF SNOW IS NOT
OUT OF THE QUESTION.

DURING THE LATE EVENING THROUGH OVERNIGHT HOURS...A SECONDARY
TROUGH WILL ROTATE SOUTHEAST ACROSS THE FA. SOME LIGHT SNOW IS
LIKELY...ESPECIALLY OVER OUR FAR NORTHERN TIER OF COUNTIES WITH
PERHAPS A HALF INCH OF SNOW. THEREFORE...RAISED POPS INTO THE LIKELY
CATEGORY FOR THIS AREA WITH CHANCE POPS FOR A FEW ROWS OF COUNTIES
TO THE SOUTH. ADDED FLURRIES ELSEWHERE OVERNIGHT AND FRIDAY
MORNING WITH THE COLD...MOIST...CYCLONIC FLOW.

DEBATED ON WHAT TO DO WITH THE WIND ADVISORY IN EFFECT THROUGH THE
NIGHT. I WOULD PREFER TO SEE AT LEAST A 10 MB PRESSURE GRADIENT
FROM KMSP TO THE SD BORDER. WE ARE CURRENTLY RUNNING AT 8 MB AND
MOST SOLUTIONS KEEP IT THIS WAY THROUGH THE NIGHT. HOWEVER...
EXAMINATION OF THE VERTICAL PROFILES FROM THE NAM THROUGH BUFKIT
INDICATE WEST CENTRAL THROUGH SOUTH CENTRAL MN AS HAVING PRETTY
GOOD POTENTIAL FOR SEEING 30 MPH SUSTAINED WINDS DURING THE
EVENING HOURS. IN ADDITION...TOP OF THE CHANNEL MOMENTUM TRANSFER
INDICATES THE POTENTIAL FOR EAST CENTRAL MN...INCLUDING THE TWIN
CITIES...TO HAVE GUSTS POTENTIAL NEAR 45 MPH DURING THE EVENING AS
WELL. LOOKING AT THE SREF...SEVERAL NMMB MEMBERS WERE BETWEEN 42
AND 45 KNOTS ADDING CONFIDENCE TO THE NAM SOLUTION. EVEN THE
FAVORITE ARW KF MEMBER WAS AT 42 KNOTS. HENCE...WILL NOT MESS WITH
THE ADVISORY AT THIS TIME WITH PLENTY OF POTENTIAL FOR
VERIFICATION OVER THE NEXT 8 TO 12 HOURS.

IT WILL BE BLUSTERY AND COLD OVER THE AREA TOMORROW AS BRISK
NORTHWEST WINDS CONTINUE. HIGHS WILL ONLY BE IN THE 20S. FACTOR IN
THE WIND AND THE APPARENT TEMPERATURE IS ONLY IN THE SINGLE DIGITS
AND TEENS. THERE SHOULD BE SOME FLURRIES AS WELL OVER EASTERN
AREAS IN THE MORNING.

NOTHING TOO EXCITING DURING THE WEEKEND OR NEXT WEEK. HIGH PRESSURE
WILL PASS BY ON SATURDAY WITH A LITTLE MODERATION IN TEMPERATURE
FOR SUNDAY BEFORE ANOTHER COLD FRONT PUSHES THROUGH ON MONDAY.
THERE ARE SOME DIFFERENCES BETWEEN THE GFS/GEM AND THE ECMWF
REGARDING A LOW PRESSURE SYSTEM PASSING SOUTH OF US MONDAY NIGHT
AND TUESDAY. THE GFS/GEM HAVE IT FARTHER NORTH WITH SNOW INTO FAR
SOUTHERN MN WHILE THE ECMWF HAS HIGH PRESSURE OVER IA WITH THE LOW
WAY SOUTHEAST. COLLABORATION WAS TO LEAVE THE SMALL POPS IN THE
FAR SOUTH PART OF MN DUE TO THE DIFFERENCES.

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WIND ADVISORY UNTIL 6 AM CST FRIDAY FOR ANOKA-BLUE EARTH-BROWN-
CARVER-CHIPPEWA-DAKOTA-DOUGLAS-FARIBAULT-FREEBORN-GOODHUE-
HENNEPIN-KANDIYOHI-LAC QUI PARLE-LE SUEUR-MARTIN-MCLEOD-
MEEKER-NICOLLET-POPE-RAMSEY-REDWOOD-RENVILLE-RICE-SCOTT-
SHERBURNE-SIBLEY-STEARNS-STEELE-STEVENS-SWIFT-TODD-WASECA-
WASHINGTON-WATONWAN-WRIGHT-YELLOW MEDICINE.

WI...NONE.
&&

RAH/BORGHOFF

AREA FORECAST DISCUSSION

NWS NORTH PLATTE NE

602 PM CST THU NOV 22 2012

.AVIATION...WINDS WILL DIMINISH FOR A PERIOD EARLY THIS
EVENING...THEN EXPECT ANOTHER INCREASE IN WINDS LATER IN THE
EVENING AND OVERNIGHT /ROUGHLY 03Z TO 08Z/ AS AN ARCTIC COLD FRONT
MOVES THROUGH THE REGION FROM NORTH TO SOUTH. THE STRONGEST WINDS
ARE EXPECTED OVER NORTH CENTRAL NEBRASKA...INCLUDING THE KVTN TAF
SITE. WINDS IN THESE AREAS COULD AGAIN GUST UP TO 40 MPH. WINDS
WILL DIMINISH BY MORNING WITH BENIGN AVIATION WEATHER CONDITIONS
FOR FRIDAY.

.PREV DISCUSSION... /ISSUED 238 PM CST THU NOV 22 2012/

DISCUSSION...
THE ARCTIC FRONT APPEARS TO BE ENTERING NWRN SD THIS AFTN. THE
LATEST NAM AND RAP SOLNS SHOW THIS FRONT DROPPING THRU NCNTL NEB
THIS EVENING WITH WINDS ALOFT INCREASING TO 65KT AT 700MB...50KT
AT 850MB AND 25 TO 30KT AT 500M AGL. SO SFC WINDS COULD RUN 25 TO
30 MPH ALONG THE FRONT AND POTENTIAL GUSTS TO 45 MPH. THUS THE
WIND ADVISORY WILL BE EXTENDED ACROSS PARTS OF NCNTL NEB TONIGHT
IN ANTICIPATION OF THIS FRONTAL PASSAGE.

ARCTIC HIGH PRESSURE SLIDES THROUGH THE MISSOURI BASIN FRIDAY AND
INTO THE MID SOUTH BY SATURDAY MORNING. WITH THE ARCTIC HIGH
BUILDING THROUGH THE MISSOURI BASIN...THE COLD CORE NEVER REACHES
FAR WESTERN NEB SO A QUICK TEMPERATURE REBOUND CAN OCCUR SATURDAY
AS NEW LOW PRESSURE TRACKS THROUGH SRN SASKATCHEWAN AND MANITOBA
TURNING TO THE WEST ACROSS THE FCST AREA.

THIS LOW THEN DROPS ANOTHER ARCTIC FRONT INTO SOUTH DAKOTA SUNDAY
WITH NW FLOW ALOFT MAINTAINING A BAROCLINIC ZONE AND WEAK MID
LEVEL FRONTOGENESIS DEVELOPING. THE SFC FRONT IS FCST TO DROP
THROUGH NRN NEB SUNDAY AFTERNOON AND THE MODELS SUGGEST
SUFFICIENT LOW LEVEL MOISTURE FOR A CHANCE OF LIGHT RAIN OR SNOW
SUNDAY AFTERNOON CHANGING TO SNOW SUNDAY NIGHT AND ENDING MONDAY
MORNING. LIGHT ACCUMULATIONS WOULD DEVELOP GIVEN THE FLEETING
NATURE OF THE MID LEVEL FRONT...THE OPEN WAVE AT 700MB SHOWN BY
ALL MODELS AND 250 MB JET MAX MOVING THROUGH SRN NEB.

WEAK ARCTIC HIGH PRESSURE MOVES QUICKLY THROUGH THE FCST AREA TUESDAY
FOLLOWED BY ANOTHER LOW PRESSURE SYSTEM TRACKING ALONG THE
CANADIAN BORDER WEDNESDAY. THIS SYSTEM WILL PULL ANOTHER FAST
MOVING ARCTIC HIGH PRESSURE SYSTEM INTO THE FCST AREA FOR NEXT THURSDAY.

SAVE FOR ISOLATED FLURRIES WITH THE ARCTIC FRONT TONIGHT AND LIGHT
SNOW POSSIBLE LATE SUNDAY AND MONDAY MORNING...THE FORECAST IS
DRY. TEMPERATURES RANGE FROM 30S AND 40S NORTHEAST TO 40S AND 50S
SOUTHWEST.

FIRE WEATHER...

OBSERVATIONS ACROSS WESTERN NEBRASKA HAVE GOTTEN NEAR RED FLAG
CRITERIA THIS AFTERNOON AS WINDS GUSTED BETWEEN 35 AND 45
MPH...WHILE DEW POINTS DROPPING INTO THE SINGLE DIGITS AND LOW TEENS
LOWERED RELATIVE HUMIDITY INTO THE UPPER TEENS AND LOW 20S.
HOWEVER...COLDER AIR WAS IN PLACE...WITH TEMPERATURES ONLY IN THE
MID AND UPPER 40S. ALTHOUGH CONDITIONS ARE CLOSE...AND MAY EVEN HIT
CRITERIA IN LOCALIZED SPOTS FOR A FEW HOURS...THESE LOWER
TEMPERATURES WILL KEEP FROM ISSUING A SHORT FUSED RED FLAG WARNING
FOR THE REMAINDER OF THE AFTERNOON. THAT BEING SAID...WITH THE
STRONG WINDS...ANY FIRES WILL STILL HAVE THE POTENTIAL TO SPREAD
RAPIDLY THIS AFTERNOON.

BEYOND TODAY...SATURDAY COULD SEE ELEVATED FIRE WEATHER CONDITIONS
WITH RELATIVE HUMIDITY DROPPING INTO THE UPPER TEENS AND
20S...HOWEVER WINDS ARE ONLY FORECAST AT 15 TO 20 MPH AT THE PEAK.
OTHERWISE THE REMAINDER OF THE NEXT 7 DAYS SHOULD BE QUIET FOR FIRE
CONCERNS.

.LBF WATCHES/WARNINGS/ADVISORIES...WIND ADVISORY UNTIL 4 AM CST
FRIDAY FOR NEZ005>010-025>029-038.

SHORT TERM/EXTENDED...WFO LBF
AVIATION...TAYLOR

AREA FORECAST DISCUSSION

NWS RALEIGH NC

1256 PM EST WED NOV 21 2012

.SYNOPSIS...
HIGH PRESSURE REMAINS OVER THE REGION THROUGH THE THANKSGIVING
HOLIDAY. A COLD FRONT MOVES THROUGH FRIDAY NIGHT. WHILE THE COLD
FRONT WILL MOVE THROUGH THE AREA DRY...THE FRONT WILL PROVIDE FOR
NOTICEABLY COLDER AND BREEZY CONDITIONS SATURDAY.

.NEAR TERM /THROUGH THURSDAY/...
AS OF 950 AM WEDNESDAY...

AS THE SHORTWAVE TROUGH ALOFT OVER THE SOUTHEAST CONTINUES TO DIG
SOUTHEAST...THE PATCHY CLOUDS ASSOCIATED WITH THE WAVE...MAINLY
OVER THE SOUTHWEST PIEDMONT INTO SOUTH CAROLINA...HAVE ALSO MOVED
SOUTHEAST AND ERODED SOMEWHAT WITH TIME ON SATELLITE IMAGERY. THE
LATEST NAM AND RUC GUIDANCE ARE FAIRLY SIMILAR IN SHOWING SOME
UPPER-LEVEL MOISTURE ESPECIALLY TOWARD KFAY INTO THIS AFTERNOON...
WITH DRYING EVEN IN THE UPPER LEVELS THERE DURING THE AFTERNOON.
PATCHY LOW CLOUDS WERE ERODING AS WELL...AND WITH A DRY AND STABLE
OVERALL AIR MASS...ANTICIPATE CONSIDERABLE SUNSHINE WITH MOSTLY
SCATTERED CLOUDS MOVING EAST FROM THE SOUTHWEST PIEDMONT ACROSS THE
SANDHILLS. AREAS ALONG AND SOUTH OF A LINE FROM ABOUT KAFP TO KCTZ
INCLUDING KFAY COULD HAVE A PERIOD OF BROKEN MID-LEVEL CLOUDS...BUT
THE DAY SHOULD STILL AVERAGE MOSTLY SUNNY. MORNING 1000-850MB
THICKNESSES WHEN COMBINED WITH ANTICIPATED VALUES IN THE AFTERNOON
CORRESPOND WELL WITH MOS GUIDANCE AND ONGOING HIGHS...AND ALTHOUGH
MIXING WILL STRUGGLE TO REACH TO 850MB...GIVEN THE BETTER INSOLATION
OF TODAY AS COMPARED TO TUESDAY...WILL ANTICIPATE SIMILAR HIGHS...
AROUND 60. THERE WILL BE SOME WIND GUSTS IN THE TEENS KNOTS...
HIGHEST TOWARD INTERSTATE 95 WHERE ALREADY KCTZ NOTED A GUST IN THE
UPPER TEENS KNOTS JUST AFTER 1430Z. THIS WOULD BE ABOUT THE MAXIMUM
GUST ANTICIPATED BASED ON THE CONSENSUS OF THE LATEST GFS AND NAM
BUFR SOUNDINGS. -DJF

TONIGHT...RIDGING AND HEIGHT RISES ALOFT IN THE WAKE OF THE TROUGH
AXIS WILL YIELD CLEAR AND ASSOCIATED CHILLY CONDITIONS TONIGHT.
PERSISTENCE LOWS IN THE LOWER 30S TO NEAR 40 DEGREES...HIGHEST
AMIDST NORTHERLY STIRRING WITHIN THE TIGHTEST PRESSURE GRADIENT OVER
THE COASTAL PLAIN.

THANKSGIVING DAY...CONTINUED RIDGING AND HEIGHT RISES ALOFT AND
ASSOCIATED SUBSIDENCE WILL YIELD SUNNY AND CONTINUED MILD WEATHER
FOR THANKSGIVING...WITH HIGH TEMPERATURES AGAIN IN THE UPPER 50S TO
LOWER 60S. FURTHER DEEPENING OF THE WESTERN ATLANTIC LOW AND...AN
ASSOCIATED CONTINUED RELATIVE MAXIMUM IN THE PRESSURE GRADIENT OVER
EASTERN NC...WILL RESULT IN A NOTICEABLE NNE 10-15 MPH BREEZE AGAIN
WITH GUSTS TO NEAR 20 MPH INVOF AND ESPECIALLY EAST OF I-95...WITH
LIGHTER WIND TO THE WEST.

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
AS OF 130 AM WEDNESDAY...

HIGH PRESSURE IN PLACE TO START THE PERIOD DAMPENS QUICKLY ON FRIDAY
AS A LOW PRESSURE SYSTEM AND ASSOCIATED SURFACE COLD FRONT APPROACH
THE AREA. ALTHOUGH WARM AIR WILL BE ADVECTING INTO CENTRAL NC OUT
AHEAD OF THE FRONT...ITS SOURCE IS A DRY CONTINENTAL AIRMASS WITHOUT
MUCH MOISTURE ADVECTION FROM THE GULF. THE GFS CONTINUES TO SHOW
WESTERLY FLOW ABOVE THE BOUNDARY LAYER WEST OF THE MTNS...WHICH
SUPPORTS DOWNSLOPE FLOW. THUS...EXPECT A DRY FRONTAL PASSAGE FRIDAY
AFTERNOON. GIVEN THE MOISTURE IN THE UPPER LEVELS THERE WILL LIKELY
BE HIGH CLOUDS OUT AHEAD OF THE FRONT AND WITH THE MOISTURE
CONVERGENCE ALONG THE FRONT...EXPECT A LAYER OF CLOUDS NEAR 850 MB
ALONG THE FRONT WITH DRYING FROM THE TOP DOWN BEHIND IT. LOW TEMPS
THURSDAY NIGHT IN THE MID TO UPPER 30S. WITH THE WARM ADVECTION
AHEAD OF THE FRONT HAVE HIGHS IN THE MID 60S FRIDAY...AND WITH
CURRENT TIMING OF THE FRONT EXPECT FRIDAY NIGHT LOWS IN THE MID 30S
NW TO LOW 40S SE.

.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 255 AM WEDNESDAY...

SATURDAY THROUGH MONDAY:
SKIES WILL CONTINUE CLEARING FROM NW TO SE ON SATURDAY AS THE COLD
FRONT PUSHES OFFSHORE. FORECAST 1000-850 MB THICKNESS VALUES
DECREASE BY APPROX 70 METERS FROM 00Z SATURDAY TO 00Z SUNDAY. WHILE
THIS IS LIKELY A LITTLE OVER DONE AND MAY NOT ACCOUNT FOR THE
ADIABATIC WARMING WITH THE STRONG NW WINDS OFF THE MTNS BEHIND THE
FRONT ON SATURDAY...TEMPS WILL STILL BE SIGNIFICANTLY COLDER THAN
FRIDAY...WITH HIGHS IN THE UPPER 40S NW TO MID 50S SE AND OVERNIGHT
LOWS IN THE UPPER 20S TO LOW 30S. AS SURFACE HIGH PRESSURE BUILDS
INTO THE AREA OVERNIGHT...THE MAIN UPPER LEVEL TROUGH AXIS WILL
SHIFT OFFSHORE. AS THE HIGH MOVES OVER CENTRAL NC AND OFF THE NC
COAST SUNDAY NIGHT...WINDS SPEEDS WILL DECREASE AT THE SURFACE AND
ALOFT WHILE SURFACE WINDS SHIFT FROM NW TO SW. WILL CONTINUE TO HAVE
WEST TO NORTHWEST WINDS ABOVE THE BOUNDARY LAYER WITH GOOD
SUBSIDENCE AND ADIABATIC WARMING...YIELDING A STRONG SUBSIDENCE
INVERSION AT THE TOP OF THE MIXED LAYER. LOW LEVEL THICKNESSES WILL
RECOVER SOME IN THE NW ON SUNDAY RESULTING IN TEMPS A COUPLE DEGREES
WARMER...LOW 50S... WHILE HIGHS ELSEWHERE WILL BE ABOUT THE SAME TO
A LITTLE COOLER THAN SATURDAY...LOW TO MID 50S. ALTHOUGH THE LOW
LEVEL THICKNESSES GRADUALLY INCREASE ACROSS THE AREA SUNDAY
NIGHT...CLEAR SKIES AND LIGHT WINDS NEAR THE SURFACE UNDER THE HIGH
WILL YIELD OVERNIGHT LOWS ONLY SLIGHTLY WARMER IN THE NW TO SIMILAR
TO THE PREVIOUS NIGHT ACROSS THE SE...MAINLY IN THE LOW 30S. IN
ADDITION TO THE INCREASING THICKNESSES...RELATIVELY WARM AIR WILL
BEGIN ADVECTING INTO CENTRAL NC FROM THE SSW ON MONDAY. AS SKIES
WILL REMAIN CLEAR TO PARTLY CLOUDY FOR MUCH OF THE DAY EXPECT HIGHS
IN THE MID 50S TO NEAR 60.

MONDAY NIGHT AND TUESDAY:
SURFACE LOW OVER THE TX PANHANDLE 00Z TUESDAY WILL MOVE EAST AND
THEN NE OVER THE MS RIVER VALLEY BY DAYBREAK TUESDAY. WILL SEE
INCREASING HIGH CLOUDS BEGINNING MONDAY EVENING. THIS LOW PRESSURE
SYSTEM WILL HAVE GOOD MOISTURE FEED INTO IT FROM THE GULF OF MEXICO
AS IT MOVES EASTWARD. AS THE WARM MOIST AIR ADVECTS INTO THE AREA ON
TUESDAY SKIES WILL QUICKLY BECOME OVERCAST AND AS THE TROUGH
APPROACHES SSW SURFACE WINDS WILL INCREASE. AS OF THE MOST RECENT
MODEL RUNS...COULD SEE PRECIP REACHING THE WESTERN PARTS OF OUR AREA
AROUND 18Z AND PROGRESSING EASTWARD THROUGH THE END OF THE PERIOD.
AS SUCH...WILL CARRY A SLIGHT CHANCE OF PRECIP ACROSS THE NW PRIOR
TO 12Z TUESDAY...INCREASING TO CHANCE IN THE NW TO SLIGHT CHANCE IN
THE SE BY 00Z WEDNESDAY. EXPECT MONDAY NIGHT LOWS IN THE UPPER 30S
TO LOW 40S WITH HIGHS ON TUESDAY IN THE MID 50S NW TO LOW 60S SE.
HOWEVER...TEMPS ON TUESDAY MAY CHANGE IF CHANGES IN TIMING OF PRECIP
OCCUR. GIVEN THAT THIS SYSTEM IS COMING IN AT THE END OF THE
FORECAST PERIOD AND THERE ARE STILL SOME DIFFERENCES IN TIMING
BETWEEN THE MODELS...CONFIDENCE IN EITHER PARAMETER IS NOT
PARTICULARLY HIGH AT THIS POINT IN TIME.

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 1255 PM WEDNESDAY...

VFR CONDITIONS WILL PERSIST THROUGH THE 18Z VALID TAF PERIOD. A FEW
NORTH TO NORTHEAST WIND GUSTS IN THE TEENS KNOTS WILL CONTINUE
THROUGH MID-AFTERNOON...AND MORE OF THE SAME WITH GUSTS A COUPLE OF
KNOTS HIGHER WILL OCCUR THURSDAY. LIGHTEST WINDS WILL BE TOWARD THE
TRIAD THIS AFTERNOON THROUGH THURSDAY. OVERNIGHT...AVIATION
INTERESTS SHOULD BE PREPARED FOR NORTH-TO-NORTHEAST WINDS INCREASING
TO BETWEEN 25 AND 30KT BY 2000FT. GIVEN THE EXPECTED AVERAGE SURFACE
WIND...LOW-LEVEL WIND SHEAR WAS ON THE LOW MARGINS AND WAS NOT
INCLUDED IN THE 18Z VALID TAF FOR LOCATIONS LIKE KFAY AND KRWI...
WHERE WINDS NEAR 2000FT AND JUST ABOVE SHOULD BE THE HIGHEST IN
CENTRAL NORTH CAROLINA OVERNIGHT.

BEYOND THE 18Z VALID TAF PERIOD...A DRY COLD FRONT MOVES THROUGH
FRIDAY NIGHT. UNDER VFR CONDITIONS...A NORTHWEST WIND GUSTING TO THE
MID TO UPPER 20S KNOTS CAN BE EXPECTED SATURDAY. THE NEXT THREAT
FOR SUB-VFR CONDITIONS...DEPENDING ON THE AMOUNT OF MOISTURE RETURN
INTO CENTRAL NORTH CAROLINA ON AN INCREASING SOUTHWEST FLOW...WILL
BE LATE MONDAY NIGHT.

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

SYNOPSIS...DJF
NEAR TERM...DJF/MWS
SHORT TERM...KC
LONG TERM...KC
AVIATION...DJF

AREA FORECAST DISCUSSION

NWS RALEIGH NC

950 AM EST WED NOV 21 2012

.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER THE EASTERN US THROUGH THANKSGIVING.
A PAIR OF MOISTURE-STARVED COLD FRONTS WILL CROSS THE MIDDLE
ATLANTIC REGION FRIDAY NIGHT.

.NEAR TERM /THROUGH THURSDAY/...
AS OF 950 AM WEDNESDAY...

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
AS OF 130 AM WEDNESDAY...

.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 255 AM WEDNESDAY...

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
AS OF 950 AM WEDNESDAY...

CONTINUED HIGH PRESSURE WILL RESULT IN VFR CONDITIONS THROUGH THE
TAF PERIOD. A NNE BREEZE WILL INCREASE INTO THE 8-12KT RANGE WITH
OCCASIONAL GUSTINESS INTO THE MID TEENS KTS AT EASTERN TERMINALS...
WITH LIGHTER WINDS TO THE WEST. WHILE NEAR SURFACE WINDS WILL BECOME
GENERALLY LIGHT (LESS THAN 5 KTS) TO CALM OVERNIGHT...NNE WINDS JUST
ABOVE THE SURFACE ARE FORECAST TO STRENGTHEN TO AROUND 30 KTS...AND
THIS MAY RESULT IN MARGINAL LOW LEVEL WIND SHEAR CONDITIONS BETWEEN
03-12Z...MAINLY EAST OF TRIAD TERMINALS.

LOOKING AHEAD: GENERALLY VFR CONDITIONS WILL PREVAIL IN HIGH
PRESSURE THROUGH THE END OF THE WORK WEEK. A PAIR OF DRY/VFR COLD
FRONTS WILL CROSS OUR REGION FRIDAY NIGHT...THE SECOND AND STRONGER
OF WHICH WILL USHER IN MUCH COOLER AIR WITH BREEZY/WINDY NW SURFACE
WINDS ON SATURDAY.

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

SYNOPSIS...MWS
NEAR TERM...DJF/MWS
SHORT TERM...KC
LONG TERM...KC
AVIATION...DJF/MWS

AREA FORECAST DISCUSSION

NWS NASHVILLE TN

722 PM CST THU NOV 22 2012

.UPDATE...
BAND OF SHOWERS STRETCHES FROM CENTRAL IL SW THROUGH THE ARKLATEX
REGION. LATEST HRRR DATA STILL SHOWS THE SOLID LINE OF SHOWERS
REACHING INTO THE NW THIRD OF MIDDLE TN BETWEEN MIDNIGHT AND 6
AM...THEN POINTS SW AROUND AND JUST AFTER SUNRISE. FOR THE MOST
PART...MOSTLY CLOUDY SKIES IS CURRENTLY THE RULE ACROSS THE MID
STATE. WILL GO AHEAD AND ADJUST THE SKY GRIDS TOWARD A LITTLE MORE
IN THE WAY OF CLOUDINESS OVERNIGHT. ADDITIONALLY...WILL GO AHEAD
AND EXPAND THE SLIGHT CHANCE OVERNIGHT A LITTLE FURTHER EASTWARD.
WILL BUMP POPS UP SOME AS WELL. REMAINDER OF FCST IN GOOD SHAPE.

.PREV DISCUSSION... /ISSUED 552 PM CST THU NOV 22 2012/

UPDATE...FOR 00Z AVIATION DISCUSSION.

AVIATION...00Z AVIATION DISCUSSION.
VEIL OF BKN CI EXPECTED TO CONTINUE ACROSS MID STATE THRU AT LEAST
23/10Z...WITH A WEAK FRONTAL PASSAGE EXPECTED ACROSS THE MID
STATE FROM 23/10Z-23/18Z. SFC WIND SHIFT LINE STILL LOOKING TO
PASS CKV AROUND 23/12Z...BNA AROUND 23/14Z...AND CSV AROUND
23/18Z. FRONTAL PASSAGE WILL BRING WITH IT ONLY LIGHT PCPN.
VFR VSBYS WITH VFR CEILINGS...HIGH MVFR CEILINGS CSV...EXPECTED
BEFORE FRONTAL PASSAGE. CLRING SKIES EXPECTED BEHIND FRONTAL
PASSAGE WITH SFC GUSTS TO 20KTS POSSIBLE CKV/BNA.

PREV DISCUSSION.../ISSUED 234 PM CST THU NOV 22 2012/

DISCUSSION...HIGH PRESSURE STILL HANGING IN ACROSS MIDDLE
TENNESSEE, BUT WILL SLIDE OFF FURTHER TO THE EAST AS A STRONG
COLD FRONT APPROACHES THE MID STATE. FRONT CURRENTLY STRETCHES
FROM THE UPPER MIDWEST INTO THE SOUTHERN PLAINS. WARM AIR PILING
UP AHEAD OF THE FRONT, WITH AFTERNOON TEMPERATURES RUNNING A FEW
DEGREES ABOVE EARLIER FORECAST. LOW-LEVEL AIR REMAINS VERY DRY,
WITH DEW POINT DEPRESSIONS RUNNING CLOSE TO 30 DEGREES. EXPECT
MOISTURE ADVECTION TO INCREASE THIS EVENING AND OVERNIGHT AS THE
PRESSURE GRADIENT STRENGTHENS, WITH SHOWERS CREEPING INTO
NORTHWEST MIDDLE TENNESSEE AFTER MIDNIGHT, AND SCATTERED SHOWERS
SPREADING ACROSS THE MID STATE FRIDAY MORNING. THIS WILL BE A LOW-
QPF EVENT, WITH PRECIPITATION EXPECT TO END BY NOON, THEN MUCH
COLDER AIR MOVING IN FRIDAY EVENING AND EARLY SATURDAY MORNING.
LOOK FOR A QUICK WARM-UP SUNDAY AND MONDAY AS WE GET RETURN FLOW
AHEAD OF THE NEXT ACTIVE SYSTEM.

.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS AMARILLO TX

415 PM CST WED NOV 21 2012

.DISCUSSION...
CONTINUED DRY CONDITIONS AND PERIODIC FRONTAL PASSAGES HIGHLIGHT THE
FORECAST PERIOD.

SOUTHWESTERLY WINDS AND CLOUD COVER HAVE INCREASED TODAY IN ADVANCE
OF A SHORTWAVE TROUGH NOW EJECTING THROUGH THE AMBIENT SOUTHWESTERLY
FLOW ALOFT. WHILE MOST OF THE FORCING/ASCENT AND MEANINGFUL RAIN
CHANCES ASSOCIATED WITH THIS FEATURE WILL REMAIN WELL SOUTH OF THE
AREA...SOME ENHANCED VORTICITY/DEEPENING OF THE TROUGH HAS EMERGED THIS
AFTERNOON OVER CENTRAL NEW MEXICO. ISOLATED HIGH-BASED CONVECTION HAS
DEVELOPED NEAR ROSWELL. ALL NWP SOLUTIONS MINIMIZE PROSPECTS FOR
PRECIPITATION IN THE PANHANDLES AS THIS TRANSLATES OVER THE REGION
TONIGHT. ONLY THE RAP DEPICTS THE SMALLEST HINT OF QPF OVER THE
SOUTHWESTERN PANHANDLE. THUS WE HAVE MAINTAINED A DRY FORECAST WITH
GRIDDED POPS AT/BELOW 10 PERCENT.

A FRONT IS EXPECTED TO PUSH ACROSS THE PANHANDLES AFTER 12-15Z
THURSDAY IN WAKE OF THE PASSING SHORTWAVE TROUGH AXIS. 3-HR PRESSURE
RISES AROUND 4 MB OVER KANSAS WILL SUPPORT POST FRONTAL WINDS OF 15
TO 25 MPH...ESPECIALLY OVER THE OKLAHOMA PANHANDLE AND THE NORTHERN
TEXAS PANHANDLE. ALL INDICATIONS OF SUFFICIENT LIFT/MOISTURE TO
SUPPORT CONVECTION ALONG THE FRONT ARE DISPLACED WELL EAST AND SOUTH
OF THE REGION.

A 1035-1037 MB CONTINENTAL SURFACE HIGH WILL PUSH SOUTHWARD THROUGH
THE PLAINS IN WAKE OF THE FRONT. THIS WILL RESULT IN NOTABLY COOLER
TEMPERATURES /SOME 5 DEGREES BELOW SEASONAL AVERAGES/ BY FRIDAY. THE
COOL SURFACE RIDGE WILL TRANSLATE SOUTHEAST TOWARD THE LOWER
MISSISSIPPI VALLEY...LENDING TOWARD TEMPERATURE MODERATION OVER THE
PANHANDLES THROUGH THE WEEKEND. THIS AS LOW AMPLITUDE RIDGING OVER
THE WEST RESULTS IN MODEST NORTHWESTERLY FLOW OVER THE CENTRAL/SOUTHERN
PLAINS AND LEE TROUGHING.

ATTENTION THEN SHIFTS TOWARD A SHORTWAVE TROUGH AND ASSOCIATED FRONTAL
PASSAGE EARLY NEXT WEEK. THE INITIAL FRONTAL PASSAGE WILL OCCUR DURING
THE LATE SUNDAY/EARLY MONDAY TIMEFRAME...AND MAY RESULT IN PROBLEMATIC
TEMPERATURE FORECASTS INITIALLY. THE FRONT WILL FINALLY PUSH SOLIDLY
THROUGH BY LATE MONDAY AS THE APPROACHING SHORTWAVE TROUGH AMPLIFIES
IN NORTHWESTERLY FLOW. SOME SOLUTIONS GENERATE LIGHT QPF IN PROXIMITY
TO THE NORTHERN AND EASTERN PANHANDLES...BUT CONFIDENCE IN SUFFICIENT
FORCING/MOISTURE IS NOT HIGH AND THE CURRENT DRY FORECAST CONTINUES TO
APPEAR VALID.

.FIRE WEATHER...
ONGOING ELEVATED FIRE WEATHER OVER THE WESTERN AND CENTRAL OKLAHOMA
PANHANDLE AND NORTHWESTERN TEXAS PANHANDLE WILL DIMINISH BY EARLY
EVENING. CONCERNS FOR ELEVATED CONDITIONS WILL AGAIN EXIST THURSDAY...
AS POST FRONTAL WINDS INCREASE INTO THE 15 TO 20 MPH RANGE AND AFTERNOON
HUMIDITY MINIMA DROP TOWARDS 15 PERCENT AGAIN OVER THE WESTERN OKLAHOMA
PANHANDLE AND THE NORTHWESTERN TEXAS PANHANDLE. OTHERWISE...ELEVATED
OR CRITICAL CONDITIONS ARE NOT ANTICIPATED THROUGH THE REMAINDER OF THE
PERIOD.

.PRELIMINARY POINT TEMPS/POPS...
AMARILLO TX 46 68 30 53 27 / 5 0 0 0 0
BEAVER OK 47 63 27 52 26 / 5 0 0 0 0
BOISE CITY OK 39 64 24 51 27 / 5 0 0 0 0
BORGER TX 48 67 33 54 31 / 5 0 0 0 0
BOYS RANCH TX 44 65 29 53 26 / 5 0 0 0 0
CANYON TX 46 69 29 53 27 / 10 0 0 0 0
CLARENDON TX 50 73 34 55 30 / 5 5 0 0 0
DALHART TX 35 64 23 52 23 / 5 0 0 0 0
GUYMON OK 42 66 25 55 26 / 5 0 0 0 0
HEREFORD TX 45 71 28 55 26 / 10 0 0 0 0
LIPSCOMB TX 51 68 30 54 27 / 5 0 0 0 0
PAMPA TX 48 66 31 52 29 / 5 0 0 0 0
SHAMROCK TX 52 75 35 57 31 / 5 5 5 0 0
WELLINGTON TX 52 78 37 58 32 / 5 5 5 0 0

.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.

15/10

AREA FORECAST DISCUSSION

NWS LA CROSSE WI

522 AM CST WED NOV 21 2012

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
341 AM CST WED NOV 21 2012

AT 3 AM...DENSE FOG WAS REDUCING VISIBILITIES TO A QUARTER MILE OR
LESS GENERALLY EAST OF A LINE FROM MENOMINEE WISCONSIN TO OELWEIN
IOWA. WITH TEMPERATURES AT OR BELOW FREEZING ACROSS MONROE...
JUNEAU...ADAMS...JACKSON...AND CLARK COUNTIES THERE IS SOME
CONCERN THAT SOME LIGHT ICING IS OCCURRING. THIS COULD MAKE THE
MORNING COMMUTE HAZARDOUS. AS THE WINDS INCREASE THIS MORNING...THE
FOG WILL BEGIN TO DISSIPATE BETWEEN 15Z AND 17Z IN CENTRAL WISCONSIN
AND ON THE BLUFF TOPS OF SOUTHEAST MINNESOTA AND NORTHEAST IOWA.
MODEL SOUNDINGS SUGGEST THAT THE MISSISSIPPI AND WISCONSIN RIVER
VALLEYS WILL BE THE LAST TO CLEAR /BETWEEN 16Z AND 18Z/. FOR
SIMPLICITY...SET THE EXPIRATION TIME OF THE DENSE FOG ADVISORY AT
18Z. THIS WILL MAKE IT EASIER TO CLEAR OUT THE COUNTIES AS THE
VISIBILITIES IMPROVE THIS MORNING.

FOR THIS AFTERNOON...THE 21.00Z MODELS ARE IN GOOD AGREEMENT THAT
SKIES WILL BE MOSTLY SUNNY WHICH WILL ALLOW THE AREA TO MIX UP
INTO THE 950 TO 925 MB RANGE. THE DEEPEST MIXING WILL OCCUR
OUTSIDE OF THE MISSISSIPPI AND WISCONSIN RIVER VALLEYS. MANY AREAS
SOUTH OF THE INTERSTATE 94 CORRIDOR WILL WARM INTO THE LOWER AND
MID 60S...AND INTO THE MID AND UPPER 50S NORTH OF THIS INTERSTATE.
DUE TO THE FOG HOLDING ON LONGER /WHICH LEADS TO LESS MIXING/...THE
MISSISSIPPI AND WISCONSIN RIVER VALLEYS WILL LIKELY SEE THEIR HIGH
TEMPERATURES ONLY TOP OUT AROUND 60 DEGREES.

FOR TONIGHT...A TIGHT PRESSURE SURFACE GRADIENT WILL KEEP THE
SOUTH WINDS IN THE 10 TO 20 MPH RANGE. THIS WILL KEEP THE BOUNDARY
LAYER WELL MIXED...THUS PREVENTING A NOCTURNAL INVERSION FROM
FORMING. AS A RESULT...THE TEMPERATURES WILL ONLY FALL INTO THE
MID AND UPPER 40S.

ON THANKSGIVING DAY...A COLD FRONT WILL MOVE EAST THROUGH
SOUTHEAST MINNESOTA AND NORTHEAST IOWA DURING THE MORNING...AND
WESTERN WISCONSIN DURING THE AFTERNOON. THERE WILL BE ENOUGH
SUNSHINE FOR TEMPERATURES TO CLIMB INTO THE 55 TO 60 DEGREE RANGE...
AND THEN TEMPERATURES WILL FALL INTO THE MID AND UPPER 30S FOR
NORTHEAST IOWA AND SOUTHEAST MINNESOTA...AND IN THE LOWER AND
MID 40S FOR WESTERN WISCONSIN.

FOR THURSDAY NIGHT INTO FRIDAY...A STRONG SHORT WAVE TROUGH WILL
MOVE ACROSS NORTHERN MINNESOTA AND NORTHERN WISCONSIN. THIS SYSTEM
WILL PRODUCE MEASURABLE SNOW ACROSS THESE AREAS. THERE MAY BE EVEN
A DUSTING OF SNOW ACROSS TAYLOR COUNTY. WITH THE BUFKIT MODEL
SOUNDINGS SUGGESTING THAT THERE WILL BE STEEP 950 TO 850 MB LAPSE
RATES INCLUDED FLURRIES DURING THE OVERNIGHT AND ON FRIDAY FOR THE
REST OF THE AREA. EARLY RISERS FOR THE BLACK FRIDAY SALES WILL
ENCOUNTER WIND CHILLS RANGING FROM 10 TO 20 DEGREES.

.LONG TERM...SATURDAY THROUGH TUESDAY
341 AM CST WED NOV 21 2012

ON SATURDAY NIGHT...THE 21.00Z MODELS SUGGEST THAT A COLD FRONT
WILL MOVE EAST THROUGH THE FORECAST AREA. WITH THE 280 TO 270K
ISENTROPIC CONDENSATION PRESSURE DEFICITS RUNNING FROM 50 TO
100 MB AND THE SOUNDINGS SHOWING DRY AIR BELOW 8K FEET...KEPT THIS
PERIOD DRY FOR NOW.

FROM MONDAY NIGHT INTO TUESDAY...BOTH THE GFS AND ECMWF
DETERMINISTIC MODELS ARE SHOWING THE POTENTIAL FOR SOME MEASURABLE
SNOW TO FALL ACROSS THE AREA AS A LOW PRESSURE SYSTEM MOVES
FROM THE MID MISSISSIPPI RIVER VALLEY INTO THE EASTERN GREAT
LAKES. WHILE THESE MODELS ARE IN GOOD AGREEMENT THE 00Z GFS
ENSEMBLE MEMBERS SHOWED QUITE A FEW DIFFERENT SCENARIOS AMONG ITS
12 FAMILY MEMBERS. SOME OF THEM WERE IN AGREEMENT WITH THE
DETERMINISTIC GFS. MEANWHILE OTHERS SUGGESTED THAT THIS LOW WOULD
REMAIN WEAK AND STAY OVER THE SOUTHEAST UNITED STATES OR IT WOULD
TRACK FURTHER WEST WHICH WOULD RESULT IN MIXED PRECIPITATION. EVEN
THE 16 RUNS OF GEM SHOWED QUITE A FEW DIVERSE 500 MB PATTERNS. ALL
OF THIS LEADS TO LITTLE CONFIDENCE WITH THIS TIME PERIOD...SO KEPT
PRECIPITATION CHANCES AROUND 20 PERCENT.

.AVIATION...TODAY AND TONIGHT
522 AM CST WED NOV 21 2012

AT KLSE...INCREASING SOUTH WINDS AHEAD OF LOW PRESSURE IN THE
DAKOTAS HAS BEEN HELPING TO GRADUALLY IMPROVE CONDITIONS.
ALTHOUGH CEILINGS ARE STILL LIFR...VISIBILITIES HAVE IMPROVED TO
IFR. THE COMBINATION OF THE WINDS ALONG WITH DAYTIME HEATING WILL
MIX OUT THE FOG AND STRATUS IN THE MISSISSIPPI RIVER VALLEY...
EXPECTED TO BE COMPELTED DISSIPATED BY 18Z. THE RAP MODEL...WHICH
DID A GOOD JOB YESTERDAY SUGGESTING THE FOG WOULD STAY IN PLACE
THROUGH THE DAY...TODAY AGREES ABOUT THE FOG AND STRATUS
DISSIPATING BY 18Z. VFR CONDITIONS ARE THEN EXPECTED THROUGH
TONIGHT WITH A DEEP DRY AIRMASS IN PLACE ABOVE THE VALLEY.

AT KRST...PLAN ON VFR CONDITIONS TO CONTINUE THROUGH TONIGHT.

REGARDING THE WINDS...SOUTH WINDS SHOULD HOLD AROUND 10 KT AT KLSE
THROUGH TONIGHT...BUT COULD GUST UP TO 20 KT THIS AFTERNOON.
CONFIDENCE ON THE GUSTS IS NOT HIGH ENOUGH TO INCLUDE AT THIS
TIME. WITH 40 KT WINDS ABOVE THE SURFACE AT 1500 FT...HAVE
INCLUDED LOW LEVEL WIND SHEAR FOR THE AFTERNOON. THE WINDS AT 1500
FT ARE PROGGED TO INCREASE TONIGHT TO 50 KT AS THE LOW PRESSURE
AREA DEEPENS OFF TO OUR WEST. AT KRST...SOUTH WINDS SHOULD
INCREASE TOWARDS 15 KT BY NOON WITH GUSTS UP TO 25 KT...AND
PERSIST THROUGH TONIGHT. WITH THE 50 KT SOUTHWEST WINDS AT 1500
FT TONIGHT...ENOUGH WIND DIFFERENCE EXISTS FOR A NEED TO INCLUDE
LOW LEVEL WIND SHEAR AT KRST AS WELL.

.CLIMATE...
341 AM CST SUN NOV 18 2012

RECORD HIGH TEMPERATURES FOR TODAY/21ST AND THURSDAY/22ND. COOP
SITES ARE 7 AM-7 AM HIGHS...THUS 22ND HIGHS ARE 21.12Z TO 22.12Z.
LA CROSSE AND ROCHESTER ARE THE ONLY NON-COOP SITES.

FORECAST HIGH TEMPERATURES SUGGEST SOME OF THE RECORDS BELOW MAY
BE TIED OR BROKEN.

LOCATION TODAY/21ST THURSDAY/22ND

LA CROSSE WI 72/1990 59/1963
SPARTA WI 65/1990 70/1990
MEDFORD WI 59/1913 65/1990
LANCASTER WI 66/2003 66/1898
MAUSTON WI 67/2003 66/1990

ROCHESTER MN 69/1990 65/1913
AUSTIN MN 70/1990 58/1966
WINONA DAM 5A MN 60/2003 60/2001
WABASHA MN 61/1908 59/1908

CHARLES CITY IA 71/1990 62/1966
OELWEIN IA 71/1990 62/1966
DECORAH IA 71/1990 62/1908

.ARX WATCHES/WARNINGS/ADVISORIES...
522 AM CST WED NOV 21 2012

WI...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR WIZ017-029-032>034-
041>044-053>055-061.

MN...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR MNZ088-096.

IA...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR IAZ010-011-029-030.

SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...AJ
CLIMATE......JONES/DB/AJ/BOYNE

AREA FORECAST DISCUSSION

NWS LA CROSSE WI

342 AM CST WED NOV 21 2012

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
341 AM CST WED NOV 21 2012

.LONG TERM...SATURDAY THROUGH TUESDAY
341 AM CST WED NOV 21 2012

.AVIATION...THROUGH 06Z THURSDAY
1136 PM CST TUE NOV 20 2012

LATEST RAP CONTINUES TO SHOW THAT THE LOW LEVEL MOISTURE REMAINS
TRAPPED BELOW THE SUBSIDENCE INVERSION AT KLSE THROUGH MOST OF THE
MORNING...AND THEN THIS MOISTURE MIXES OUT QUICKLY AS THE GRADIENT
INCREASES. DUE TO THIS...EXTENDED THE LIFR CEILINGS AND
VISIBILITIES FROM 21.07Z TO 21.17Z. IN THE HIGHER ELEVATIONS
ALONG THE MISSISSIPPI AND WISCONSIN...AND IN CENTRAL WISCONSIN
EXPECT THAT THE DENSE FOG WILL DISSIPATE QUICKLY BETWEEN 21.16Z
AND 21.18Z. ONCE THE INVERSION BREAKS EXPECT VFR CEILINGS AND
VISIBILITIES FOR THE REMAINDER OF THIS TIME PERIOD.

ORIGINALLY THOUGHT THAT THE LOW CEILINGS AND VISIBILITIES MAY GET
INTO KRST...BUT WITH THE DENSE CIRRUS NOW OVERHEAD AND WINDS
NEAR 10 KNOTS EXPECT THAT THE RADIATIVE COOLING MAY HAVE SLOWED
ENOUGH TO PREVENT THIS FROM OCCURRING. WITH THIS SAID...THE
VISIBILITIES WILL LIKELY BECOME MVFR DUE TO HAZE BETWEEN 21.09Z
AND 21.17Z. OTHERWISE...BOTH THE CEILINGS AND VISIBILITIES SHOULD
BE VFR THROUGH THE REMAINDER OF THE PERIOD.

.CLIMATE...
341 AM CST SUN NOV 18 2012

RECORD HIGH TEMPERATURES FOR TODAY/21ST AND THURSDAY/22ND. COOP
SITES ARE 7 AM-7 AM HIGHS...THUS 22ND HIGHS ARE 21.12Z TO 22.12Z.
LA CROSSE AND ROCHESTER ARE THE ONLY NON-COOP SITES.

FORECAST HIGH TEMPERATURES SUGGEST SOME OF THE RECORDS BELOW MAY
BE TIED OR BROKEN.

LOCATION TODAY/21ST THURSDAY/22ND

LA CROSSE WI 72/1990 59/1963
SPARTA WI 65/1990 70/1990
MEDFORD WI 59/1913 65/1990
LANCASTER WI 66/2003 66/1898
MAUSTON WI 67/2003 66/1990

ROCHESTER MN 69/1990 65/1913
AUSTIN MN 70/1990 58/1966
WINONA DAM 5A MN 60/2003 60/2001
WABASHA MN 61/1908 59/1908

CHARLES CITY IA 71/1990 62/1966
OELWEIN IA 71/1990 62/1966
DECORAH IA 71/1990 62/1908

.ARX WATCHES/WARNINGS/ADVISORIES...
341 AM CST WED NOV 21 2012

WI...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR WIZ017-029-032>034-
041>044-053>055-061.

MN...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR MNZ079-088-096.

IA...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR IAZ010-011-029-030.

SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...BOYNE
CLIMATE......JONES/DB/AJ/BOYNE

AREA FORECAST DISCUSSION

NWS LA CROSSE WI

1137 PM CST TUE NOV 20 2012

.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT
601 PM CST TUE NOV 20 2012

MAIN FORECAST CONCERN IS ON CLOUDS/FOG POTENTIAL TONIGHT...
TEMPERATURES THROUGH THE PERIOD AND RAIN CHANCES FOR THANKSGIVING
DAY.

ALREADY GETTING REPORTS OF VSBYS NEAR ZERO IN FOG BETWEEN 23Z-00Z
LATE THIS AFTERNOON...AS MOISTURE/BR/LOW CLOUDS FROM TODAY PERSIST
ACROSS PORTIONS OF THE AREA. LIGHT WINDS...CLEAR/MOSTLY CLEAR SKIES
AND RADIATIONAL COOLING WILL ONLY ALLOW THE FOG TO BECOME MORE
WIDESPREAD AND VSBYS TO CONTINUE DROPPING THRU THE EVENING HOURS.
THUS HAVE HOISTED ANOTHER DENSE FOG ADVISORY FOR TONIGHT INTO
WEDNESDAY MORNING...STARTING AT 00Z IN THE AREAS WHERE THE FOG/LOW
CLOUDS PERSISTED TODAY. STARTED ADVISORY IN PORTIONS OF CENTRAL
WISCONSIN...WHERE SUNNY SKIES ALLOWED FOR PLENTY OF WARMING/MIXING
OF THE BOUNDARY LAYER TODAY...AT 03Z.

LEFT ANY FOG ADVISORY OUT OF THE NORTH END OF THE FCST AREA...WHERE
CIRRUS CLOUDS WILL SPREAD OVER DURING THE MID EVENING HOURS AND
LIMIT RADIATIONAL COOLING. LEFT FOG ADVISORY OUT OF THE HIGHER
ELEVATION PORTIONS OF NORTHEAST IA/SOUTHEAST MN...WHERE GRADIENT
WINDS EXPECTED TO INCREASE INTO THE 8-15KT RANGE AROUND MIDNIGHT AND
AFTER. THIS INCREASED BOUNDARY LAYER MIXING LATER TONIGHT SHOULD
LIMIT THE DENSE FOG POTENTIAL IN THOSE AREAS.

.LONG TERM...
301 PM CST TUE NOV 20 2012

MEDIUM RANGE MODELS DO SHOW SOME DIFFERENCES IN THIS TIME FRAME.
20.12Z ECMWF HAS BACKED OFF ON A NEGATIVELY TILTED TROUGH DEVELOPING
EARLY NEXT WEEK AND NOW HAS MAINLY A ZONAL FLOW REGIME. GFS AND
ECMWF DO DIFFER WITH SOME SUBTLE WAVES EXPECTED TO TRANSLATE THROUGH
THE FLOW FROM SUNDAY THROUGH TUESDAY. SURFACE HIGH PRESSURE WILL
DOMINATE THE PATTERN SATURDAY...BUT AFTER THAT CONFIDENCE IS RATHER
LOW IN ANY ONE SOLUTION AND THUS HAVE WENT WITH THE MODEL CONSENSUS.
TEMPERATURES LOOK TO REMAIN BELOW NORMAL THROUGH THE PERIOD...WITH
HIGHS MAINLY IN THE 30S WITH LOWS IN THE TEENS AND 20S.

.AVIATION...THROUGH 06Z THURSDAY
1136 PM CST TUE NOV 20 2012

.CLIMATE...
200 AM CST SUN NOV 18 2012

RECORD HIGH TEMPERATURES FOR WEDNESDAY/21ST AND THURSDAY/22ND. COOP
SITES ARE 7 AM-7 AM HIGHS...THUS 22ND HIGHS ARE 21.12Z TO 22.12Z.
LA CROSSE AND ROCHESTER ARE THE ONLY NON-COOP SITES.

FORECAST HIGH TEMPERATURES SUGGEST SOME OF THE RECORDS BELOW MAY
BE TIED OR BROKEN.

LOCATION WEDNESDAY/21ST THURSDAY/22ND

LA CROSSE WI 72/1990 59/1963
SPARTA WI 65/1990 70/1990
MEDFORD WI 59/1913 65/1990
LANCASTER WI 66/2003 66/1898
MAUSTON WI 67/2003 66/1990

ROCHESTER MN 69/1990 65/1913
AUSTIN MN 70/1990 58/1966
WINONA DAM 5A MN 60/2003 60/2001
WABASHA MN 61/1908 59/1908

CHARLES CITY IA 71/1990 62/1966
OELWEIN IA 71/1990 62/1966
DECORAH IA 71/1990 62/1908

.ARX WATCHES/WARNINGS/ADVISORIES...
601 PM CST TUE NOV 20 2012

WI...DENSE FOG ADVISORY UNTIL 10 AM CST WEDNESDAY FOR WIZ032-033-
041-053>055-061.

DENSE FOG ADVISORY FROM 9 PM THIS EVENING TO 10 AM CST
WEDNESDAY FOR WIZ034-042>044.

MN...DENSE FOG ADVISORY UNTIL 10 AM CST WEDNESDAY FOR MNZ079-088-
096.

IA...DENSE FOG ADVISORY UNTIL 10 AM CST WEDNESDAY FOR IAZ010-011-
029-030.

SHORT TERM...RABERDING/RRS
LONG TERM....RABERDING
AVIATION...BOYNE
CLIMATE......JONES/DB/AJ/BOYNE

AREA FORECAST DISCUSSION

NWS DES MOINES IA

124 AM CST FRI NOV 23 2012

.UPDATE...PUBLIC WEATHER DISCUSSION.

.SHORT TERM /TONIGHT/...
CLOUDS FOLLOWING SECONDARY STRONG COLD FRONT ADVANCING OVER ENTIRE
AREA FOR THE REMAINDER OF TONIGHT. FLURRIES WILL ACCOMPANY THE COLD
AIR ESPECIALLY NORTH SECTIONS THROUGH NIGHT AND MID MORNING
TOMORROW. STRONG NW WINDS ALSO EXPECTED. /REV

.PREVIOUS EVENING UPDATE SHORT TERM /TONIGHT/...
NO CHANGES TO WIND ADVISORY OVERNIGHT. ISOLATED SITES CONTINUE TO
HIT SUSTAINED AND GUST ADVISORY CRITERIA...30 AND 45 MPH
RESPECTIVELY. AIRMASS WILL REMAIN MIXED OVERNIGHT ESPECIALLY WITH
PASSAGE OF ANOTHER COLD ADVECTION MAX AFTER 06Z ASSOCIATED WITH
SECONDARY FRONT CURRENTLY DEPICTED FROM SD INTO MN. 01Z RAP 0-500M
LAYER WINDS REMAIN FAIRLY STEADY...BUT INCREASING SLIGHTLY 06Z-13Z.

.AFTERNOON SHORT TERM /TONIGHT/...
A STRONG COLD FRONT IS PLOWING ACROSS IOWA FROM NORTHWEST TO
SOUTHEAST. THE WIND SHIFT HAS JUST PASSED THROUGH GRINNELL AND
CHARITON...AND WILL REACH OTTUMWA AND THE REST OF OUR SOUTHEASTERN
COUNTIES WITHIN THE NEXT COUPLE OF HOURS. HOWEVER...THE STRONGER
WINDS AND COLDER AIR ARE DELAYED A COUPLE OF COUNTIES BEHIND THE
WIND SHIFT...WITH TEMPERATURES ALREADY FALLING PRECIPITOUSLY ACROSS
OUR NORTHERN AREAS. LOW CLOUDS HAVE ALSO SPREAD INTO NORTHERN
IOWA...BUT FURTHER SOUTH SKIES ARE MOSTLY CLEAR.

.AVIATION...23/06Z
VFR STRATUS COVERS PORTIONS OF NRN IA AT 0530Z WITH MVFR STRATUS
JUST UPSTREAM ACROSS THE MN BORDER. THESE MVFR CIGS ARE EXPECTED TO
AFFECT AT LEAST KFOD/KMCW/KALO INTO FRI MORNING. POTENTIAL IS THERE
FARTHER SOUTH TOO...BUT CONFIDENCE NOT GREAT ENOUGH TO INCLUDE AS OF
YET. A SECONDARY PUSH OF COLD AIR AND MIXING...ESSENTIALLY
COINCIDENT WITH THE MVFR CIGS...WILL BOOST GUSTS ONCE AGAIN EARLY
FRI MORNING WITH GUSTS OVER 30KTS NORTH. MVFR CIGS SHOULD EXIT BY
LATE FRI MORNING FOLLOWED BY VERY GRADUALLY DECREASING WINDS INTO
THE AFTERNOON...AND EVENTUALLY SHARPER DECOUPLING BY SUNSET.

.DMX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY THROUGH 6 AM CST FRIDAY FOR CALHOUN-CERRO GORDO-EMMET-
HANCOCK-HUMBOLDT-KOSSUTH-PALO ALTO-POCAHONTAS-SAC-WEBSTER-WINNEBAGO-
WORTH-WRIGHT

UPDATE PUBLIC DISCUSSION...REV
AVIATION...SMALL
SHORT TERM...LEE
LONG TERM...DONAVON

AREA FORECAST DISCUSSION

NWS DES MOINES IA

1134 PM CST THU NOV 22 2012

.UPDATE...
ADDED 06Z TAF DISCUSSION.

NO CHANGES TO WIND ADVISORY OVERNIGHT. ISOLATED SITES CONTINUE TO
HIT SUSTAINED AND GUST ADVISORY CRITERIA...30 AND 45 MPH
RESPECTIVELY. AIRMASS WILL REMAIN MIXED OVERNIGHT ESPECIALLY WITH
PASSAGE OF ANOTHER COLD ADVECTION MAX AFTER 06Z ASSOCIATED WITH
SECONDARY FRONT CURRENTLY DEPICTED FROM SD INTO MN. 01Z RAP 0-500M
LAYER WINDS REMAIN FAIRLY STEADY...BUT INCREASING SLIGHTLY 06Z-13Z.

.DMX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY THROUGH 6 AM CST FRIDAY FOR CALHOUN-CERRO GORDO-EMMET-
HANCOCK-HUMBOLDT-KOSSUTH-PALO ALTO-POCAHONTAS-SAC-WEBSTER-WINNEBAGO-
WORTH-WRIGHT

UPDATE/AVIATION...SMALL
SHORT TERM...LEE
LONG TERM...DONAVON

AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

1055 PM CST THU NOV 22 2012

.AVIATION.../00Z TAF ISSUANCE/

UPPER LOW STILL PROGGED TO MOVE ACROSS THE NORTHERN PORTION OF THE
AREA OVERNIGHT WITH FORCING SHIFTING TO THE NORTHEAST. STILL WILL
LIKELY DROP TO IFR AT TIMES AS THIS UPPER TROUGH MOVES THROUGH.
CONDITIONS SHOULD IMPROVE FROM WEST TO EAST ACROSS AT LEAST MN
PORTION OF THE AREA FRIDAY. WILL GO VFR AROUND 18Z OVER WESTERN
AREAS AND THEN INTO WESTERN WISCONSIN NOT UNTIL FRIDAY EVENING. GFS
APPEARS TO BE A BIT MORE PESSIMISTIC IN HOLDING LOWER LEVEL RH.
WILL HAVE TO MONITOR THIS IN LATER FORECASTS. NORTHWEST WINDS
REMAIN STRONG INTO THE MORNING BEFORE TAPERING BY LATE AFTERNOON.

KMSP...STILL WILL SEE SOME LIGHT SNOW PASS ACROSS THE AREA
OVERNIGHT. LESS THAN ONE HALF INCH ACCUMUALTION. WILL KEEP IT JUST
ABOVE IFR. SLOW CLEARING INTO THE AFTERNOON AS SURFACE RIDGE
APPROACHES FROM THE WEST. WILL SCATTER CLOUDS AFTER 21Z AND
DIMINISH WIND THROUGH 00Z/24.

/OUTLOOK FOR KMSP/
SAT...VFR. WINDS S AT 5-10KTS.
SUN...VFR. WINDS WNW AT 5-10KTS.
MON...MAINLY VFR...POSSIBLE MVFR CIGS LATE WITH -SN. WINDS N 5 KTS.

.PREV DISCUSSION...
/ISSUED 222 PM CST THU NOV 22 2012/

WI...NONE.
&&

RAH/BORGHOFF

AREA FORECAST DISCUSSION

NWS NORTH PLATTE NE

1143 PM CST THU NOV 22 2012

.AVIATION...WINDS WILL CONTINUE TO DIMINISH THE REST OF
TONIGHT...AND BE AROUND 10 KTS FROM THE NORTHWEST DURING THE DAY
FRIDAY. VFR CONDITIONS WILL RULE AS HIGH PRESSURE CONTINUES TO
BUILD INTO THE REGION.

.PREV DISCUSSION... /ISSUED 238 PM CST THU NOV 22 2012/

FIRE WEATHER...

.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&

SHORT TERM/EXTENDED...WFO LBF
AVIATION...TAYLOR

AREA FORECAST DISCUSSION...UPDATED

NWS NASHVILLE TN

1131 PM CST THU NOV 22 2012

.UPDATE...FOR 06Z AVIATION DISCUSSION.
&&

.AVIATION...06Z AVIATION DISCUSSION.
BKN VEIL CI TO CONTINUE ACROSS MID STATE EARLY PORTION...WITH
SHORT RANGE MODELS CONTINUING TO SHOW A WEAK FRONTAL PASSAGE
EXPECTED ACROSS MID STATE FROM 23/10Z-23/18Z. SFC WIND SHIFT
LINE STILL LOOKING TO PASS CKV AROUND 23/12Z...BNA AROUND
23/14Z...AND CSV AROUND 23/18Z. STILL LOOKS LIKE FRONTAL PASSAGE
WILL BRING WITH IT ONLY LIGHT PCPN. VFR VSBYS/VFR CEILINGS...HIGH
MVFR CEILINGS CSV...EXPECTED BEFORE FRONTAL PASSAGE. CLRING SKIES
BEHIND FRONTAL PASSAGE. SFC GUSTS TO 20KTS CKV/BNA THRU 24/00Z.
&&

.PREV DISCUSSION.../ISSUED 722 PM CST THU NOV 22 2012/

UPDATE...
BAND OF SHOWERS STRETCHES FROM CENTRAL IL SW THROUGH THE ARKLATEX
REGION. LATEST HRRR DATA STILL SHOWS THE SOLID LINE OF SHOWERS
REACHING INTO THE NW THIRD OF MIDDLE TN BETWEEN MIDNIGHT AND 6
AM...THEN POINTS SW AROUND AND JUST AFTER SUNRISE. FOR THE MOST
PART...MOSTLY CLOUDY SKIES IS CURRENTLY THE RULE ACROSS THE MID
STATE. WILL GO AHEAD AND ADJUST THE SKY GRIDS TOWARD A LITTLE MORE
IN THE WAY OF CLOUDINESS OVERNIGHT. ADDITIONALLY...WILL GO AHEAD
AND EXPAND THE SLIGHT CHANCE OVERNIGHT A LITTLE FURTHER EASTWARD.
WILL BUMP POPS UP SOME AS WELL. REMAINDER OF FCST IN GOOD SHAPE.

PREV DISCUSSION.../ISSUED 552 PM CST THU NOV 22 2012/

UPDATE...FOR 00Z AVIATION DISCUSSION.

PREV DISCUSSION.../ISSUED 234 PM CST THU NOV 22 2012/

.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$
31

AREA FORECAST DISCUSSION

NWS SAN ANGELO TX

1145 PM CST THU NOV 22 2012

.DISCUSSION...

LOOK FOR GUSTY NORTH SURFACE WINDS TO DEVELOP ACROSS WEST CENTRAL
TEXAS DURING THE NEXT 6 HOURS. AVIATION BELOW HAS ADDITIONAL
INFORMATION.

.AVIATION...

THE LATEST RUC SURFACE DATA INDICATE THE COLD FRONT WILL PUSH
SOUTH ACROSS WEST CENTRAL TEXAS DURING THE NEXT 6 HOURS. THE FRONT
IS CURRENTLY LOCATED NEAR A BIG SPRING TO HASKELL LINE. NORTH OF
THE FRONT...METAR DATA INDICATE WINDS ARE GUSTING NEAR 20 KNOTS.
ALSO...THE RUC 925 MB RELATIVE HUMIDITY FIELD INDICATES STRATUS
AND ASSOCIATED MVFR CEILINGS MAY RETURN TO OUR SOUTHERN COUNTIES
AS WE WERE PREVIOUSLY THINKING. SO...I CONTINUED MVFR CEILINGS FOR
THE SONORA AND JUNCTION TERMINALS. FOR TOMORROW...LOOK FOR NORTH
WINDS AROUND 15 KNOTS...WITH POSSIBLE GUSTS RANGING FROM 25 TO 30
KNOTS. AFTER SUNSET TOMORROW EVENING...PLAN FOR NORTH WINDS TO
DIMINISH TO AROUND 10 KNOTS...AS SURFACE HIGH PRESSURE BEGINS TO
BUILD OVER TEXAS.

HUBER

.PREV DISCUSSION... /ISSUED 1013 PM CST THU NOV 22 2012/

DISCUSSION...
MADE ONLY A MINOR ADJUSTMENT TO THE AREA OF SHOWERS TO OUR SOUTH
FOR TONIGHT...PUSHING THEM SLIGHTLY FARTHER SOUTH. EXPECT SHOWERS
TO BE HELD GENERALLY SOUTH OF A LINE FROM SAN SABA TO BARNHART AS
THE FRONT IS MOVING JUST SLIGHTLY FASTER THAN EARLIER MODEL RUNS
HAD PROJECTED. GRIDS ARE PUBLISHED AND TEXT PRODUCTS ARE OUT.

PREV DISCUSSION... /ISSUED 601 PM CST THU NOV 22 2012/

DISCUSSION...

LOOK FOR A STRONG COLD FRONT TO BRING GUSTY NORTH SURFACE WINDS
TO WEST CENTRAL TEXAS LATER TONIGHT. AVIATION BELOW HAS DETAILS.

AVIATION...

ANOTHER STRONG COLD FRONT WILL SWEEP ACROSS WEST CENTRAL TEXAS
TONIGHT AND BRING GUSTY NORTH SURFACE WINDS. THE FRONT...WHICH IS
CURRENTLY IN THE TEXAS PANHANDLE...WILL MOVE INTO THE NORTHERN BIG
COUNTRY AROUND MIDNIGHT. FROM MIDNIGHT THROUGH 12Z...EXPECT
SURFACE WINDS TO RAPIDLY BECOME NORTH...WITH INITIAL GUSTS NEAR 30
KNOTS POSSIBLE. MEANWHILE...STRATUS WILL RETURN TO OUR SOUTHERN
COUNTIES TONIGHT AND BRING MVFR TO AT LEAST SONORA AND JUNCTION.
AS THE FRONT MOVES THROUGH OUR SOUTHERN COUNTIES JUST AFTER
SUNRISE TOMORROW MORNING...CEILINGS WILL LIFT INTO THE VFR RANGE.
IN ADDITION...SOME SHOWERS ARE POSSIBLE WITH THE FRONT...MAINLY
ALONG AND SOUTH OF AN OZONA TO BROWNWOOD LINE. HOWEVER...WITH ONLY
A SLIGHT CHANCE FOR SHOWERS...I DECIDED NOT TO ADD ANY WEATHER TO
ANY OF OUR TERMINALS. DURING THE DAY TOMORROW...PLAN FOR VFR
CONDITIONS...WITH GUSTY NORTH SURFACE WINDS.

HUBER

PREV DISCUSSION... /ISSUED 337 PM CST THU NOV 22 2012/

SHORT TERM...
SHOWERS ACROSS THE BIG COUNTRY HAVE COME TO AN END...WITH REMNANT
MID LEVEL CLOUD COVER AND A SPARSE CU FIELD PRESENT OVER THE EASTERN
HALF OF THE CWA. RAINFALL AMOUNTS LEFT A LITTLE TO BE DESIRED BUT
BIG COUNTRY RESIDENTS CAN BE THANKFUL FOR THE ONE OR TWO HUNDREDTHS
OF AN INCH THAT FELL THIS MORNING. A COLD FRONT IS SITUATED FROM
NEAR CLOVIS /NM/...TO CANADIAN /TX/...TO HUTCHINSON /KS/ AND WILL
CONTINUE SOUTH OVERNIGHT...MAKING ITS WAY THROUGH THE CWA AFTER
MIDNIGHT. AHEAD OF THE FRONT...WE WILL SEE LIGHT SOUTH WINDS AND
CLEAR SKIES. ONCE THE BOUNDARY PASSES...WINDS WILL SHIFT ABRUPTLY TO
THE NORTH AND INCREASE TO 15-20 MPH SUSTAINED...WITH HIGHER GUSTS.

THERE IS A SLIGHT POTENTIAL FOR CONVECTION TO INITIATE ALONG THE
FRONTAL BOUNDARY BUT THIS WOULD LIKELY BE CONFINED TO THE SOUTHERN
HALF OF THE CWA. LOW POPS WERE MAINTAINED THROUGH FRIDAY MORNING
WITH LOW QPF ANTICIPATED. THIS FRONT SHOULD BE THROUGH THE CWA BY
/OR JUST AFTER/ 12Z FRIDAY MORNING AND GUSTY NORTH WINDS OF 15-25
MPH ARE EXPECTED THROUGHOUT MOST OF THE DAY. TEMPS WILL BE ON THE
ORDER OF 15-20 DEGREES COOLER TOMORROW WITH HIGHS FORECAST TO REMAIN
IN THE LOW/MID 60S. ENHANCED MOISTURE ABOVE THE COLD DOME...IN
CONJUNCTION WITH WEAK ISENTROPIC ASCENT...WILL SUPPORT THE FORMATION
OF A STRATO CUMULUS DECK OVER THE CWA AFTER SUNRISE. THIS CLOUD
COVER WILL CLEAR FROM NORTH TO SOUTH AS DRIER AIR ADVECTS INTO THE
AREA BUT SHOULD SERVE TO KEEP TEMPS DOWN A BIT IN THE SOUTHERN
ZONES.

JOHNSON

LONG TERM...
ENOUGH DRY AIR ADVECTION SHOULD ALLOW SKIES TO GRADUALLY CLEAR OVER
OUR SOUTHERN COUNTIES FRIDAY EVENING. WINDS WILL ALSO DIMINISH DURING
THE EVENING AND BECOME LIGHT FRIDAY NIGHT...AS SURFACE HIGH DROPS
SOUTHEAST ACROSS OKLAHOMA WITH A RIDGE EXTENSION SOUTHWEST ACROSS OUR
AREA. THIS SETUP WILL FACILITATE GOOD RADIATIONAL COOLING OVERNIGHT...
AND WE ARE GOING WITH LOWS NEAR THE COLDER MAV GUIDANCE.

A STRONG TEMPERATURE RECOVERY IS IN STORE SATURDAY...AIDED BY ABUNDANT
SUNSHINE WITH SOUTH WINDS DEVELOPING. WARMER STILL FOR SUNDAY WITH
AFTERNOON HIGHS EXPECTED TO BE MOSTLY IN THE MID 70S. SOUTH-SOUTHWEST
WINDS WILL BE INCREASE AND BECOME GUSTY BY SUNDAY WITH LEE SIDE
TROUGHING AND INCREASED SURFACE PRESSURE GRADIENT. TEMPERATURES MONDAY
EXPECTED TO BE 10-15 DEGREES ABOVE NORMAL...AS 850 MB THERMAL RIDGING
SHIFTS ACROSS OUR AREA WITH SOUTHWEST TO WEST LOW-LEVEL FLOW. GIVEN
THIS SETUP...GOING ABOVE GUIDANCE MONDAY WITH HIGHS IN THE UPPER
70S TO NEAR 80 ACROSS OUR CENTRAL AND SOUTHERN COUNTIES. TIMING
OF THE NEXT COLD FRONT COMES INTO PLAY MONDAY. IF THE FRONT ENTERS
THE BIG COUNTRY DURING THE AFTERNOON...COULD RESULT IN COOLER
HIGHS FOR OUR NORTHERN COUNTIES.

THE COLD FRONT WILL PUSH SOUTH THROUGH OUR AREA MONDAY NIGHT...WITH
NORTH WINDS FOLLOWING AND COOLER TEMPERATURES FOR TUESDAY. MODELS
HAVE BEEN TRENDING WEAKER WITH THIS FRONT DURING THE PAST FEW DAYS...
WITH LESS DIGGING OF THE UPPER TROUGH ACROSS THE PLAINS STATES. NOW
APPEARS THAT IT WILL BE MORE OF A PASSING SHOT OF COOLER AIR FOLLOWED
BY A QUICK MODERATION OF TEMPERATURES WEDNESDAY INTO THURSDAY.

.PRELIMINARY POINT TEMPS/POPS...
ABILENE 43 62 32 65 44 / 10 0 0 0 0
SAN ANGELO 46 63 32 69 42 / 10 5 0 0 0
JUNCTION 52 62 33 68 39 / 20 20 0 0 0

.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

HUBER

AREA FORECAST DISCUSSION

NWS TULSA OK

939 AM CST FRI NOV 23 2012

...UPDATE...

.DISCUSSION...
TEMP TRENDS HAVE BEEN RUNNING A BIT LOWER THAN FORECAST EARLY THIS
MORNING AND LATEST SHORT TERM HOURLY DATA SUGGESTS TEMPS WILL BE
SLOW TO RISE ESPECIALLY THIS AFTERNOON. GIVEN THE ONGOING STRONG
COLD ADVECTION AND THE POCKET OF SUB ZERO 850MB TEMPS YET TO SLIDE
INTO THE AREA PER LATEST RUC DATA...THIS SLOW WARMING TREND LOOKS
PLAUSIBLE. THIS WILL ALSO LOWER HIGH TEMPS A FEW DEGREES PRIMARILY
NORTH OF INTERSTATE 40. GUSTY WINDS WILL PERSIST THROUGH THE
AFTERNOON.

.PRELIMINARY POINT TEMPS/POPS...
TUL 52 26 56 38 / 0 0 0 0
FSM 60 27 56 33 / 10 0 0 0
MLC 57 26 59 37 / 10 0 0 0
BVO 49 20 57 32 / 0 0 0 0
FYV 50 21 52 32 / 0 0 0 0
BYV 49 24 50 35 / 0 0 0 0
MKO 54 23 56 34 / 0 0 0 0
MIO 49 22 55 37 / 0 0 0 0
F10 57 26 57 38 / 0 0 0 0
HHW 58 28 57 34 / 10 0 0 0

.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&

SHORT TERM...07

AREA FORECAST DISCUSSION

NWS GREENVILLE-SPARTANBURG SC

933 AM EST FRI NOV 23 2012

.SYNOPSIS...
HIGH PRESSURE WILL WEAKEN AND SHIFT EAST AHEAD OF A COLD FRONT
MOVING THROUGH THE AREA THIS AFTERNOON. THIS FRONT WILL USHER IN
COLDER AIR WHICH WILL LINGER OVER THE WEEKEND. ANOTHER COLD FRONT IS
EXPECTED TO APPROACH THE AREA BY THE MIDDLE OF NEXT WEEK.

.NEAR TERM /THROUGH TONIGHT/...
AS OF 910 AM EST...WATCHING PRECIP WITH FRONT OVER MIDDLE TENNESSEE.
THE SHOWERS HAVE SHOWN A SLIGHT DIMINISHING TREND AS THEY ENTER THE
DRIER AIR OVER THE EASTERN HALF OF THE STATE. LATEST RAP RUN
SUGGESTED THIS WOULD OCCUR THOUGH ITS PLACEMENT OF THE PRECIP IS A
LITTLE TOO FAR WEST. IT DOES SUGGEST SOME UPSLOPE ENHANCEMENT OR
REDEVELOPMENT OVER THE CUMBERLAND PLATEAU AND THEN AS THE FRONT
ENTERS THE SMOKIES...BUT FOLLOWING ITS TRENDS OUR CWFA WOULD SEE A
LATER START TO PRECIP THAN CURRENTLY FCST AND ONLY THE TN BORDER
COUNTIES WOULD BE AFFECTED AT ALL. EXTRAPOLATING THE CURRENT MOTION
ON RADAR WOULD BRING THE PRECIP TO THE BORDER AT ABOUT 18Z. ON THESE
NOTES...DELAYED THE ONSET OF PRECIP BY A COUPLE OF HOURS.

A MAJOR SHORT WAVE TROUGH TRAVERSING THE GREAT LAKES THIS MORNING
WILL INDUCE HEIGHT FALLS ACROSS MUCH OF THE EASTERN CONUS TODAY...
ALLOWING AN ASSOCIATED COLD FRONT TO SWEEP ACROSS OUR AREA THIS
AFTERNOON. THE FRONTAL BAND OF PRECIP MOVING ACROSS THE MISS RIVER
VALLEY EARLY THIS MORNING IS ALREADY FAIRLY MEAGER. IT APPEARS THAT
AS THE SHORT WAVE APPROACHES NEW ENGLAND LATER TODAY...PRE-FRONTAL
FLOW WILL VEER...AND WE WILL LOSE WHAT LITTLE LOW LEVEL FORCING
EXISTS WITH THE FRONT. IN FACT...MODEL QPF PROGS BARELY BRING EVEN
THE LIGHTEST OF PRECIP INTO THE FAR WESTERN MTNS OF NORTH CAROLINA
THIS AFTERNOON. AS SUCH...I/VE BACKED OFF EVER SO SLIGHTLY ON
POPS...FEATURING 40-50 PERCENT IN A NARROW CORRIDOR ALONG THE TENN
BORDER...TAPERING TO ONLY 20 PERCENT NEAR THE SOUTHERN ESCARPMENT OF
THE BLUE RIDGE. A DRY FORECAST WILL BE MAINTAINED IN THE PIEDMONT...
WITH PERHAPS A BRIEF PERIOD OF BKN/OVC MID/HIGH CLOUDS BEING THE
ONLY FANFARE.

THE BIGGER STORY WILL BE THE SHARP DROP IN TEMPS AND RELATIVELY
GUSTY WINDS BEHIND THE FRONT BEGINNING THIS EVENING...ESP ACROSS THE
MTNS. TEMPS WILL DROP QUICKLY INTO THE 40S AFTER SUNSET...WITH MOST
AREAS EXPECTED TO SEE BELOW NORMAL MIN TEMPS BY SUNRISE. WINDS WILL
BE QUITE GUSTY OVER THE MTNS IN THE NW FLOW COLD ADVECTION...BUT
PROGGED PRESSURE GRADIENT AND LOW LEVEL WIND FIELDS SUPPORT SPEEDS
WELL UNDER ADVISORY CRITERIA. THERE WILL BE SHALLOW LOW LEVEL
MOISTURE ALONG THE TENN BORDER IN A MODERATE NW FLOW REGIME WITH
QUICKLY FALLING SNOW LEVELS...SO A FEW HOURS OF FLURRIES OR LIGHT
SNOW SHOWERS WILL BE POSSIBLE...SUPPORTING SLIGHT TO LOW CHANCE
POPS.

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AT 230 AM EST FRIDAY...AN UPPER TROUGH WILL BE ALONG THE EAST COAST
ON SATURDAY. AS THIS TROUGH MOVES OFFSHORE...A SOUTHERN STREAM
SHORTWAVE WILL MOVE ACROSS THE SOUTHEAST...LEAVING THE CAROLINA
COAST LATE SATURDAY NIGHT. UPPER FLOW BECOMES ZONAL ON SUNDAY AND
SUNDAY NIGHT...WITH NO SIGNIFICANT UPPER SYSTEM CROSSING OUR AREA.

NW FLOW SNOW SHOWERS WILL DIMINISH IN THE NW NC MOUNTAINS ON
SATURDAY...WHILE A THE SURFACE PRESSURE GRADIENT GRADUALLY RELAXES
OVER OUR AREA. NO SIGNIFICANT SNOW ACCUMULATIONS ARE EXPECTED ALONG
THE NORTHERN TN BORDER SATURDAY. DRY HIGH PRESSURE WILL MOVE OVER
THE SOUTHEAST ON SATURDAY NIGHT AND SUNDAY...WHILE A SURFACE FRONT
STALLS OVER THE OH AND POTOMAC RIVER VALLEYS. ON SUNDAY NIGHT...
SOUTHERLY FLOW ON THE BACK SIDE OF THE HIGH PRESSURE WILL SPREAD
GULF MOISTURE NORTH IN THE MS RIVER VALLEY....BUT OUR AREA WILL
REMAIN DRY. TEMPERATURES WILL START OUT AROUND 10 DEGREES BELOW
NORMAL IN COLD ADVECTION ON SATURDAY AND SATURDAY NIGHT...THEN WILL
WARM TO AROUND 5 DEGREES BELOW NORMAL.

.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 240 AM FRIDAY...THE MODELS CONTINUE TO SHOW AN UPPER
CONFLUENCE ZONE ACROSS THE SRN M/ATL REGION TO BEGIN THE EXT PERIOD.
AN ASSOCIATED LLVL HIGH CENTER WILL BE SITUATED WELL OFFSHORE BY
THIS TIME ALLOWING A GOOD RETURN FLOW INTO THE CAROLINA REGION. THE
S/LY FLOW WILL BE MAINLY DRY AS DEEPER GOM MOISTURE WILL BE FLUXED
AHEAD OF A DEVELOPING CYCLONE AND SFC FRONT ACROSS THE LOWER MS
VALLEY. A GOOD AMOUNT FALL INSOL WILL HAVE TO COUNTER A LEFTOVER CP
AIRMASS HOWEVER...SO MAX TEMPS SHOULD REACH RIGHT AROUND OR A DEGREE
OR SO BELOW NORMAL. THIS WILL BE THE WARMEST DAY OF THE PERIOD AS
INCREASED CLOUD COVER AND ANOTHER CP SFC HIGH WORKS IN DURING THE
WEEK.

THE GFS AND THE ECMWF DIFFER WITH THE DEEPNESS OF THE UPPER
TROF WITH THE GFS BEING MORE ACUTE AND THUS MORE DYNAMIC WITH THE
UPPER JET AND DIV WHILE THE AXIS CROSSES TO THE NE TUE AFTERNOON.
EXPECT WIDESPREAD CLOUDINESS AND PRECIP DURING FROPA WITH VERY
LIMITED SFC BASED INSTABILITY. SHEAR LEVELS SHOULD BE MODERATE GIVEN
A BLEND OF THE OP MODELS...SO REALLY NOTHING MORE THAN -SHRA IS
EXPECTED BEFORE AND DURING THE BOUNDARY PASSAGE. SOME AREAS OF DIFF
HEATING MAY ALLOW THE FORMATION OF A LOW END QLCS...BUT NOTHING REAL
STRONG OR SEVERE IS PROBABLE AT THIS TIME. A PERIOD OF NW FLOW -SNSH
WILL LIKELY DEVELOP IN WRAP AROUND MOISTURE LATE TUE INTO EARLY
WED...WITH THE NC MTN HIGHER ELEVATIONS ABOVE 3.5 KFT RECEIVING ANY
MEASURABLE...YET SUB/ADVISORY LEVEL SNOWFALL.

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
15Z UPDATE...NO SIGNIFICANT CHANGES TO TAFS EXCEPT TO ADD A LOW
END GUST MENTION AT KCLT FOR POTENTIAL TO MIX DOWN STRONGER WINDS
THIS AFTERNOON. MEANWHILE...IN UPSTATE SC...SOME SPORADIC PATCHES
OF LAKE INDUCED FOG OCCURRED EARLY THIS MORNING NEAR KCEU AND
KAND...BRIEFLY CAUSING IFR CONDITIONS AT KCEU. A FEW LOW CLOUDS
MAY HANG OVER THE AREA FOR ANOTHER HOUR OR SO THIS MORNING BUT
OPERATIONAL IMPACTS ARE NOT EXPECTED.

AT KCLT AND ELSEWHERE...VFR CONDITIONS ARE EXPECTED THROUGH THE
PERIOD. SOME PATCHY FOG/LOW STRATUS HAS DEVELOPED NEAR AREA LAKES
THIS MORNING...WITH LIFR CONDITIONS RECENTLY NOTED AT KCEU. KAND
EVEN REPORTED FEW002 BRIEFLY. WE CANNOT RULE OUT A BRIEF PERIOD OF
RESTRICTIONS AT KAND OVER THE NEXT COUPLE OF HOURS...BUT CONFIDENCE
IS LOW ATTM.

A COLD FRONT APPROACHING FROM THE TENNESSEE VALLEY WILL CROSS THE
AREA THIS AFTERNOON. THIS FRONT WILL BE DRY FOR THE VAST MAJORITY OF
THE AREA...ALTHOUGH A FEW SHOWERS WILL BE POSSIBLE THIS AFTERNOON
AND EVENING NEAR THE TENNESSEE BORDER. SOME CLOUD COVER WILL ALSO
ACCOMPANY THE FRONT...BUT THESE SHOULD BE MAINLY OF THE MID AND HIGH
LEVEL VARIETY. CALM WINDS THIS MORNING WILL GIVE WAY TO S/SW WINDS
OF 5-10 KT BY EARLY AFTERNOON. WINDS WILL TURN TOWARD THE WEST AS
THE FRONT CROSSES THE AREA THIS AFTERNOON/EVENING...THEN BECOME NW
BY LATE EVENING. GUSTS IN THE 20S WILL BE POSSIBLE AT KAVL THIS
EVENING AND EVEN THROUGH THE OVERNIGHT.

OUTLOOK...DRY HIGH PRESSURE WILL CONTROL THE WEATHER OVER THE
REGION SATURDAY THROUGH MONDAY. ANOTHER COLD FRONT WILL CROSS THE
REGION ON TUE...POSSIBLY BRINGING FLT RESTRICTIONS AND RAINFALL.

AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...

WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.

$$
SYNOPSIS...SBK
NEAR TERM...JDL/WIMBERLEY
SHORT TERM...JAT
LONG TERM...SBK
AVIATION...JDL/WIMBERLEY

AREA FORECAST DISCUSSION

NWS TULSA OK

1042 AM CST FRI NOV 23 2012

.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
VFR CONDITIONS WILL CONTINUE WITH WINDS DIMINISHING AFTER SUNSET.

.PREV DISCUSSION... /ISSUED 939 AM CST FRI NOV 23 2012/

..UPDATE...

DISCUSSION...
TEMP TRENDS HAVE BEEN RUNNING A BIT LOWER THAN FORECAST EARLY THIS
MORNING AND LATEST SHORT TERM HOURLY DATA SUGGESTS TEMPS WILL BE
SLOW TO RISE ESPECIALLY THIS AFTERNOON. GIVEN THE ONGOING STRONG
COLD ADVECTION AND THE POCKET OF SUB ZERO 850MB TEMPS YET TO SLIDE
INTO THE AREA PER LATEST RUC DATA...THIS SLOW WARMING TREND LOOKS
PLAUSIBLE. THIS WILL ALSO LOWER HIGH TEMPS A FEW DEGREES PRIMARILY
NORTH OF INTERSTATE 40. GUSTY WINDS WILL PERSIST THROUGH THE
AFTERNOON.

.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&

AVIATION...07

AREA FORECAST DISCUSSION

NWS MILWAUKEE/SULLIVAN WI

1111 AM CST FRI NOV 23 2012

.AVIATION/18Z TAFS/...993 MILLIBAR SURFACE LOW EAST OF LAKE
SUPERIOR CONTINUES TO PULL AWAY. TIGHT PRESSURE GRADIENT LINGERS
WITH THE GUSTY NW WINDS. FLURRIES STILL HERE AND THERE THOUGH
VSBYS ARE STAYING UP. SOME CLEARING ACTUALLY WORKING IN FROM THE
LAKE AND THIS ALSO IN AN AREA RIGHT BEHIND A 30 UNIT RUC DEFINED
VORT MAX SO ENHANCED SUBSIDENCE IN THAT AREA IS PLAUSIBLE.
STRATUS DECK RIGHT AROUND MVFR THRESHOLDS AND THIS WILL PERSIST
INTO THE EVENING HOURS. SUBSTANTIAL REDUCTION IN 925-850 RH AS THE
NIGHT WEARS ON SO WILL GO WITH SOME CLEARING. HIGH PRESSURE RIDGE
TO BRING CONSIDERABLY LIGHT ER WINDS FOR SATURDAY ALONG WITH MORE
IN THE WAY OF SUNSHINE.

.PREV DISCUSSION... /ISSUED 304 AM CST FRI NOV 23 2012/

TODAY AND TONIGHT...FORECAST CONFIDENCE...HIGH

A VERY STRONG MID LEVEL SHORT WAVE WAS CENTERED OVER NORTHERN
WISCONSIN EARLY THIS MORNING...AND IS EXPECTED TO MOVE NORTH OF LAKE
HURON BY THE NOON HOUR. THE ASSOCIATED SURFACE LOW IS WELL OUT AHEAD
OF THIS UPPER LEVEL FEATURE...BUT TAKING A SIMILAR PATH. SNOW SHOWERS
WITH THE SHORT WAVE WERE OVER EASTERN MN AND NORTHWEST WISCONSIN AND
SHOULD STAY NORTH OF THE FORECAST AREA TODAY. A LARGE LOWER STRATUS
DECK HAS OVERSPREAD THE AREA...REACHING INTO NORTHERN ILLINOIS. WE
COULD SEE A FEW SNOW FLAKES OUT OF THAT...OTHERWISE NOT EXPECTED
ANYTHING MEASURABLE TODAY. IN FACT...ONCE THE SHORT WAVE EXITS TO
THE EAST...THE STRONG SUBSIDENCE IN ITS WAKE MAY START TO PUNCH A
DECENT HOLE IN THE STRATUS RESULTING IN SOME AFTERNOON SUNSHINE.
HOWEVER...THE COLD ADVECTION WILL GIVE US PRETTY STEEP LOW LEVEL
LAPSE RATES THAT MAY OVERRULE THE SUBSIDENCE FOR A TIME AND KEEP THE
CLOUDS LOCKED IN A LITTLE LONGER. WINDS TO REMAIN ELEVATED TODAY
WITH GUSTS TO 30 MPH CONTINUING UNTIL MID AFTERNOON...THAT WILL PUT
WIND CHILLS IN THE UPPER TEENS TO LOWER 20S.

HIGH PRESSURE NUDGES IN TONIGHT. WE SHOULD FINALLY SEE SOME CLEARING
AND THE WINDS WILL DIMINISH. TEMPS TO FALL INTO THE MID TEENS TO LOW
20S.

SATURDAY AND SUNDAY...FORECAST CONFIDENCE...MEDIUM TO HIGH

HIGH PRESSURE WILL BRING SUNNY SKIES SATURDAY...BUT WITH 925 MB
TEMPS OF -5C AT BEST...HIGHS WILL STRUGGLE INTO THE LOW 30S. A WEAK
SHORTWAVE WILL SLIDE THROUGH THE AREA SATURDAY NIGHT...BRINGING
INCREASED CLOUDS ALONG WITH THE POSSIBILITY OF A FEW SNOWFLAKES IN
THE NORTHERN FORECAST AREA. NOT THAT EXCITED ABOUT CHANCES...AS LOW
LEVEL MOISTURE NOT THAT IMPRESSIVE...ALONG WITH PRETTY MARGINAL
LIFT. STILL...ENOUGH DEPTH TO THE SATURATION AND LIFT IN THE NORTH
TO MENTION SLIGHT CHANCE FOR LIGHT SNOW AND ISOLATED FLURRIES.

THE NAM MOVES THE SHORTWAVE THROUGH A BIT LATER THAN OTHER
MODELS...LINGERING THE SNOW CHANCES INTO SUNDAY MORNING. OPTED TO
GO WITH BULK OF OTHER SOLUTIONS...WHICH SUGGEST DRY CONDITIONS BY
SUNDAY MORNING. LOOKS A BIT MILDER SUNDAY...WITH HIGH TEMPS BACK
TOWARD NORMAL FOR LATE NOVEMBER.

MONDAY THROUGH THURSDAY...FORECAST CONFIDENCE...MEDIUM

MODELS HAVE CONTINUED DRIER TREND FOR LOW PRESSURE SYSTEM MONDAY
NIGHT INTO TUESDAY. THE CANADIAN HAD BEEN THE LONE HOLDOUT FOR
KEEPING A DECENT PRECIP EVENT GOING FOR SOUTHERN WISCONSIN...BUT THE
LATEST RUN CAME IN FARTHER SOUTH. KEPT SOME LOW POPS GOING...AS THE
GFS AND CANADIAN STILL BRUSH THE FORECAST AREA WITH SOME LIGHT SNOW.

HIGH PRESSURE IS EXPECTED TO BRING A RETURN OF QUIET WEATHER TO
SOUTHERN WISCONSIN FOR WEDNESDAY AND THURSDAY.

LOOKS LIKE TEMPERATURES WILL BE NEAR TO A COUPLE DEGREES BELOW
NORMAL FOR MUCH OF NEXT WEEK...POSSIBLY MODERATING A BIT BY THE END
OF THE WEEK.

AVIATION/12Z TAFS/...
A LARGE MVFR STATUS DECK COVERS MUCH OF THE GREAT LAKES AND UPPER
MISSISSIPPI VALLEY REGION EARLY THIS MORNING. WE SHOULD START TO SEE
AN EROSION OF THESE CLOUDS FROM WEST TO EAST BY LATE THIS
MORNING...REACHING KMKE BY LATE AFTERNOON OR EARLY EVENING.

WINDS WILL REMAIN STRONG OUT OF THE NORTHWEST THROUGH MUCH OF THE
DAYLIGHT HOURS...FINALLY DIMINISHING WITH SUNSET AND THE ARRIVAL OF
HIGH PRESSURE AND A WEAKER PRESSURE GRADIENT.

MARINE...
A GALE WARNING REMAINS IN EFFECT UNTIL 10 PM THIS EVENING...
THEREAFTER A SMALL CRAFT ADVISORY WILL LIKELY REMAIN IN EFFECT
THROUGH THE MORNING ON SATURDAY. THE STRONG NORTHWEST WINDS TODAY
WILL GRADUALLY DIMINISH BY THE EVENING HOURS AS THE PRESSURE
GRADIENT RELAXES WITH HIGH PRESSURE PUSHING INTO THE REGION.

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...GALE WARNING UNTIL 10 PM CST THIS EVENING FOR LMZ643>646.

$$
TODAY/TONIGHT AND AVIATION/MARINE...DAVIS
SATURDAY THROUGH THURSDAY...DDV