Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/30/13

AREA FORECAST DISCUSSION

NWS TUCSON AZ

157 PM MST MON JAN 28 2013

.SYNOPSIS...A WEATHER SYSTEM WILL CONTINUE TO BRING GUSTY WINDS AS
WELL AS A CHANCE OF VALLEY RAIN AND MOUNTAIN SNOW THROUGH TONIGHT.
COLD TUESDAY MORNING AND WEDNESDAY MORNING. EXPECT DRY CONDITIONS TO
RETURN THE SECOND HALF OF THE WEEK ALONG WITH WARMER TEMPERATURES.

.DISCUSSION...THE SURFACE COLD FRONT WAS MOVING THROUGH COCHISE AND
GRAHAM COUNTIES AS OF EARLY THIS AFTERNOON. THE SNOW LEVEL WAS STILL
BETWEEN 6000 AND 7000 FEET MOST AREAS...BUT WILL LOWER AS THE
EVENING GOES ON AND ESPECIALLY OVERNIGHT DOWN TO NEAR 3500 FEET.
SHOWERS HAD NOT BEEN TOO WIDESPREAD AS EXPECTED...SO WILL MAINTAIN
THE SCATTERED TYPE WORDING AND POP VALUES FOR THIS EVENING AND
TONIGHT. ALREADY SEEING SKIES PARTIALLY CLEARING BEHIND THE SURFACE
COLD FRONT ACROSS WESTERN PIMA COUNTY...BUT LATEST RAP AND HRRR
GUIDANCE SHOWING A FEW SHOWERS EVEN ACROSS THE CENTRAL/WESTERN
DESERTS AS THE TROUGH AXIS MOVES THROUGH TONIGHT. SKIES SHOULD
GRADUALLY BEGIN TO CLEAR LATE TONIGHT. THE GUSTY WINDS WILL BE
DIMINISHING THROUGH THE EVENING HOURS ONCE THE SURFACE FRONT PASSES
BY. CLEARING SKIES LATE TONIGHT...ALONG WITH COLDER AIR FILTERING
INTO THE AREA WILL RESULT IN COLDER OVERNIGHT LOWS TUESDAY MORNING.
WITH STRONG NORTHWEST FLOW ALOFT...GUSTY WINDS ARE EXPECTED
ESPECIALLY FOR THE UPPER GILA RIVER VALLEY TUESDAY AND LATER SHIFTS
MAY NEED TO CONSIDER A WIND ADVISORY. BY WEDNESDAY AND THURSDAY
MORNINGS...A SEASONABLE LIGHT FREEZE FOR THE LOWER DESERTS WILL BE
POSSIBLE. OTHERWISE...A RIDGE OF HIGH PRESSURE WILL BRING DRY
CONDITIONS AND A RAPID REBOUND IN AFTERNOON TEMPERATURES THE SECOND
HALF OF THE WEEK. THEREAFTER... MEDIUM RANGE MODELS SHOWED A SYSTEM
AFFECTING THE AREA AROUND SUNDAY INTO EARLY MONDAY WITH
PRECIPITATION POSSIBLE.

.AVIATION...BKN-OVC CLOUDS 5-8K FT AGL AND MTNS OBSCD...WITH SCT
-SHRA/SHSN THRU TONIGHT...THEN SKIES GRADUALLY CLEARING TUESDAY
MORNING. WINDS GENERALLY WLY-SWLY 12-22 KTS WITH HIGHER GUSTS EAST
OF TUCSON THROUGH 06Z TUESDAY...THEN MAINLY LESS THAN 10 KTS THROUGH
TUESDAY MORNING FROM KTUS WESTWARD AND 10-20 KTS ACROSS EASTERN
AREAS. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

.FIRE WEATHER...NO FIRE WEATHER CONCERNS. SCATTERED SHOWERS AND
BREEZY CONDITIONS INTO THIS EVENING. STRONGEST WINDS WILL BE FOR
EASTERN COCHISE COUNTY WHERE GUSTS ABOVE 35 MPH ARE POSSIBLE THROUGH
LATE AFTERNOON. DRY WEATHER TUESDAY BUT WINDY ESPECIALLY IN THE
UPPER GILA RIVER VALLEY. TEMPERATURES WILL BEGIN TO MODERATE
WEDNESDAY WITH DRY CONDITIONS CONTINUING.

.TWC WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY TIL 11 PM TONIGHT FOR AZZ510

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON

AREA FORECAST DISCUSSION

NWS TUCSON AZ

240 AM MST MON JAN 28 2013

.SYNOPSIS...ANOTHER WEATHER SYSTEM WILL BRING GUSTY WINDS AS WELL AS
A CHANCE OF VALLEY RAIN AND MOUNTAIN SNOW TODAY AND TONIGHT. COLD
TUESDAY MORNING AND WEDNESDAY MORNING. EXPECT DRY CONDITIONS TO
RETURN THE SECOND HALF OF THE WEEK ALONG WITH WARMER TEMPERATURES.

.DISCUSSION...COLD FRONT PUSHING INTO FAR WESTERN PIMA COUNTY AS OF
2AM. SOUTHWESTERLY FLOW INCREASING JUST AHEAD OF IT WITH BANDS AHEAD
OF THE FRONT STILL MAINLY NORTH. NAM12 AND HRRR CONTINUE TO SHOW
ADDITIONAL SHOWER DEVELOPMENT AHEAD OF AND WITH THE FRONT AS IT
PUSHES THROUGH OUR CWA TODAY. CONSIDERING NARROW WINDOW WITH PRECIP
ASSOCIATED WITH THE FRONT AND FAIRLY RAPID CLEARING BEHIND IT THE
EVENING SHIFT INDICATED THIS WITH 3 HR INCREMENTS TO THE POP GRIDS.
WE TWEAKED THIS BASED ON 06Z NAM...HRRR TRENDS AND LATEST ECMWF
INPUT...BUT HAVE LARGELY KEPT THESE INTACT.

SNOW LEVELS CURRENTLY NEAR 7-8K FEET WILL FALL QUICKLY WITH THE
FRONT TO 4500 FEET THIS AFTERNOON AND LOWER THIS EVENING...HOWEVER
BY THEN THE BEST MOISTURE WILL BE EAST OF OUR AREA. STILL UNABLE TO
SQUEEZE OUT WIDESPREAD ADVISORY LEVEL SNOWS WITH 3 TO 6 INCHES
EXPECTED ABOVE 7000 FEET TODAY AND TONIGHT...1 TO 3 INCHES BETWEEN
5000 AND 7000 FEET...AND A LIGHT DUSTING TO 1 INCH POSSIBLE BETWEEN
3500 AND 5000 FEET. WE`LL MONITOR PRECIP TRENDS CLOSELY TO VERIFY
THIS WHILE ALSO WATCHING FOR ANY MODERATE TO HEAVY PRECIP THAT MAY
BRING LOCALIZED FLOODING CONCERNS WHEN ADDED TO SATURDAY`S HEAVY
PRECIP TOTALS.

GUSTY WINDS TODAY MAINLY AHEAD OF THE FRONT BUT SHOULD REMAIN BELOW
ADVISORY LEVELS THERE AS WELL...WITH THE POSSIBLE EXCEPTION BEING
OUR MOST WIND PRONE EASTERN ZONE LOCATIONS WHICH ALSO HAPPEN TO BE
FAR ENOUGH AHEAD OF THE FRONT FOR STRONGER WINDS TO MIX DOWN DURING
THE DAY...WE`LL HAVE TO KEEP AN EYE ON THAT.

CLEARING FROM THE WEST TONIGHT...WIDESPREAD FREEZE WEST TO HARD
FREEZE EAST TUESDAY MORNING AND WEDNESDAY MORNING BUT NOTHING
UNUSUAL FOR LATE JANUARY.

DRY CONDITIONS WITH TEMPERATURES JUMPING BACK ABOVE CLIMO THE SECOND
HALF OF THE WEEK INTO THIS COMING WEEKEND...TO START FEBRUARY WITH
RELATIVELY MILD CONDITIONS.

.AVIATION...BKN-OVC CLOUDS 5-8K FT AGL AND MTNS OBSCD THROUGH THIS
AFTERNOON. ISOLD -SHRA EARLY THIS MORNING BECOMING SCT -SHRA AFTER
11Z MONDAY. SFC WINDS GENERALLY 8 TO 12 KTS THROUGH 14Z...THEN SWLY
10-20 KTS WITH HIGHER GUSTS EAST OF TUCSON THROUGH 00Z TUESDAY.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

.FIRE WEATHER...NO FIRE WEATHER CONCERNS. SCATTERED SHOWERS AND
BREEZY CONDITIONS TODAY. STRONGEST WINDS WILL BE FOR EASTERN
COCHISE COUNTY WHERE GUSTS ABOVE 35 MPH ARE POSSIBLE. DRY WEATHER
TUESDAY BUT WINDY ESPECIALLY IN THE UPPER GILA RIVER VALLEY.
TEMPERATURES WILL BEGIN TO MODERATE WEDNESDAY WITH DRY CONDITIONS
CONTINUING.

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON

M/M

AREA FORECAST DISCUSSION

NWS TAMPA BAY RUSKIN FL

850 PM EST TUE JAN 29 2013

.UPDATE (TONIGHT THROUGH WEDNESDAY)...
01Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A NOW HIGHLY AMPLIFIED
UPPER LEVEL PATTERN IN PLACE ACROSS THE CONUS. MAIN FEATURE OF NOTE
IS A SHARP AND DEEP TROUGH TRAVERSING THE CENTRAL PORTION OF THE
COUNTRY AND FORCING A SIGNIFICANT SEVERE WEATHER OUTBREAK ACROSS THE
CENTRAL AND LOWER MS VALLEY. IMPRESSIVE HEIGHT FALLS SPREADING
EASTWARD HELPED TO AMPLIFY THE DOWNSTREAM RIDGE ALONG THE EASTERN
SEABOARD DURING THE PAST 24 HOURS AND GAVE US YET ANOTHER
UNSEASONABLY WARM DAY. IN FACT...IT WAS WARM ENOUGH TO FORCE A
DECENT SEA-BREEZE CIRCULATION BY LATE TODAY...AND THIS FOCUS HAS
ACTUALLY BEEN STRONG ENOUGH TO SUPPORT A FEW LIGHT SHOWERS ACROSS
WESTERN MANATEE AND WESTERN HILLSBOROUGH COUNTIES THE PAST COUPLE
HOURS (JANUARY?).

AS WE COOL INTO THE LATE EVENING AND THE LOW LEVEL FOCUS
RELAXES...THESE ISOLATED SHOWERS SHOULD END AND GENERALLY ANTICIPATE
A DRY AND WARM OVERNIGHT PERIOD.

STACKED RIDGING PATTERN WE HAVE ENJOYED FOR SEVERAL DAYS WILL
QUICKLY EXIT DURING WEDNESDAY AS THE LARGE SCALE TROUGH AND
ASSOCIATED HEIGHT FALLS SPREAD ACROSS THE SOUTHEAST CONUS.
ASSOCIATED SURFACE COLD FRONT WILL ALSO BE PROGRESSING EASTWARD
ACROSS THE GULF AND FL PANHANDLE THROUGH THE DAY. STILL APPEARS AS
THOUGH THE BEST SYNOPTIC FORCING AND LOW LEVEL FOCUS FOR
SHOWERS/ISOLATED STORMS WILL HOLD OFF UNTIL WEDNESDAY EVENING FOR
THE NATURE COAST...AND MAINLY TOWARD OR AFTER MIDNIGHT FOR THE I-4
CORRIDOR SOUTHWARD. THEREFORE...FORECAST FOR WEDNESDAY WILL FEATURE
MORE WARM TEMPERATURES AND ALSO INCREASING DEWPOINTS WITHIN A DEEP
SOUTHERLY FLOW. AS MENTIONED ABOVE...WILL KEEP RAIN OUT OF THE
FORECAST FOR THE DAYLIGHT HOURS...WITH THE EXCEPTION OF POTENTIALLY
LEVY AND CITRUS COUNTIES WHERE INITIAL LEADING SHOWERS COULD START
AS EARLY AS THE LATE AFTERNOON HOURS.

AS THE HIGHER DEWPOINT AIR BEGINS TO MOVE NORTHWARD AHEAD OF THE
FRONT...WILL NEED TO WATCH FOR THE POTENTIAL DEVELOPMENT OF SOME
ADVECTION SEA-FOG LATE WEDNESDAY/WEDNESDAY EVENING. BEST CHANCES TO
SEE THIS FOG DEVELOPMENT WOULD BE FROM TAMPA BAY NORTHWARD ALONG THE
NATURE COAST WHERE SHELF WATERS ARE CURRENTLY COOLEST.

.AVIATION...
SIMILAR TO LAST NIGHT...LOW CLOUDS AND MAYBE SOME FOG WILL DEVELOP
BETWEEN 06-08Z. BEST CHANCES AT SEEING IFR CONDITIONS WILL BE LAL...
TPA AND PIE. VFR AFTER 15Z BUT GUSTY SOUTHERLY WINDS POSSIBLY TO 30
KNOTS.

.MARINE...
HIGH PRESSURE THAT HAS BEEN DOMINATING WATERS WILL BEGIN TO SLIDE
AWAY TONIGHT AS A COLD FRONT MOVES INTO THE WESTERN GULF AND TRACKS
EASTWARD...REACHING THE EAST GULF WED NIGHT/EARLY THU THEN SWEEPING
OUT OF THE STATE DURING THU. HIGH PRESSURE BUILDS IN OVER THE GULF
REGION FRI THEN MOVES EAST DURING THE WEEKEND.

BOATING CONDITIONS BEGIN TO DETERIORATE TONIGHT AS WINDS INCREASE TO
EXERCISE CAUTION SPEEDS LATER AND WILL HEADLINE THAT WITH THE
AFTERNOON FORECAST. WINDS MOST LIKELY REACH SMALL CRAFT ADVISORY
CRITERIA WED MORNING AND CONTINUE INTO FRI.

THE ARRIVAL OF HIGHER DEWPOINT AIR BY LATE WEDNESDAY AFTERNOON/WED
EVENING WILL LEAD TO SOME POTENTIAL DEVELOPMENT OF ADVECTION
SEA-FOG. BEST CHANCES TO SEE THIS FOG DEVELOPMENT WOULD BE FROM
TAMPA BAY NORTHWARD ALONG THE NATURE COAST WHERE SHELF WATERS ARE
CURRENTLY COOLEST. THE WINDOW FOR ANY SEA-FOG IS BRIEF AS THE
PASSAGE OF THE COLD FRONT WEDNESDAY NIGHT WILL END THIS POTENTIAL.

.PRELIMINARY POINT TEMPS/POPS...
TPA 66 80 60 67 / 10 0 60 10
FMY 65 83 65 73 / 10 0 60 20
GIF 63 83 59 68 / 10 0 60 10
SRQ 65 78 62 68 / 10 0 60 10
BKV 63 82 57 65 / 10 10 60 10
SPG 66 77 61 67 / 10 0 60 10

.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.

UPDATE...MROCZKA
AVIATION...JILLSON

AREA FORECAST DISCUSSION

NWS COLUMBIA SC

647 AM EST MON JAN 28 2013

.SYNOPSIS...
HIGH PRESSURE WILL HOLD ACROSS THE AREA THROUGH TUESDAY. A STRONG
COLD FRONT CROSS THE AREA LATE WEDNESDAY BRINGING SHOWERS AND
POSSIBLE THUNDERSTORMS. COOL AND DRY HIGH PRESSURE WILL RETURN
FOR THE END OF THE WEEK.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THIS MORNING...DEVELOPING IN-SITU WEDGE OVER AREA. LIGHT EAST TO
NORTHEAST SURFACE WINDS. RUC SHOWS WEAK SHORT WAVE WHICH WILL
TRAVERSE THE AREA DURING THE DAY. THIS COMBINED WITH WEAK
ISENTROPIC LIFT AS SOUTHERLY WINDS ABOVE SURFACE BASED WEDGE BRING
WARMER AIR ALOFT...THUS PROVIDING CONDITIONS FAVORABLE FOR WEAK
ISENTROPIC LIFT. WILL KEEP THE SLIGHT CHANCE OF LIGHT RAIN THIS
MORNING. BUT ISENTROPIC LIFT APPEARS TO BE STRONGER JUST TO THE
WEST OF CAE...SO INCLUDED AN CHANCE AREA (30-40 PERCENT) OF LIGHT
RAIN MAINLY DURING THE MORNING. TEMPERATURES IN THE UPPER 30S
SHOULD RISE INTO THE 40S.

THIS AFTERNOON...WEDGE WEAKENS. NOT SURE IT WILL COMPLETELY BREAK
DOWN BUT SURFACE WINDS ARE EXPECTED TO BECOME MORE SOUTHERLY. WILL
GRADUALLY DECREASE POPS TO ABOUT 10 PERCENT BY LATE AFTERNOON.
WENT WITH HIGHS IN THE 50S WITH SORT OF A BLEND BETWEEN MODEL DATA
AND THE MAX WEDGE TEMPERATURE TOOL. WITH MORE RAIN IN THE MORNING
DECIDED TO LOWER HIGHS ABOUT 2 DEGREES...FROM UPPER 40S FAR NORTH
THE UPPER 50S FAR SOUTH.

.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
WEDGE IS EXPECTED TO HAVE ERODED BY TONIGHT. IN THE ABSENCE OF
ISENTROPIC LIFT...WILL GO WITH POPS 10 PERCENT OR LESS TONIGHT
THROUGH EARLY TUESDAY NIGHT. LATER TUESDAY NIGHT...A WEATHER SYSTEM
WITH AN APPROACHING COLD FRONT WILL BEGIN TO PULL MOISTURE TO THE
REGION. WILL INCREASE POPS TO 20-30 PERCENT AFTER TUESDAY NIGHT
AFTER MIDNIGHT. LOWS TONIGHT INT HE 40S. HIGHS TUESDAY IN THE
LOWER TO MIDDLE 70S AND LOWS TUESDAY NIGHT UP IN THE UPPER 50S.

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS THE HIGH BECOMES CENTERED OFFSHORE AND SOUTHERLY FLOW BRINGS
WARM AIR TO REGION WEDNESDAY. A STRONG COLD FRONT WILL MOVE
QUICKLY THROUGH THE REGION ON WEDNESDAY BRINGING PRECIPITATION TO
THE AREA. HAVE INCLUDED THUNDER DUE TO THE STRONG DYNAMICS OF THE
SYSTEM EVEN THOUGH INSTABILITY APPEARS LIMITED AT THIS TIME. THE
CWA WILL BE IN THE RIGHT ENTRANCE REGION OF A LLJ AND UPPER LEVEL
JET AND PWAT VALUES ARE RELATIVELY HIGH FOR THIS TIME OF YEAR. THE
FRONTAL BOUNDARY WILL PROVIDE ADDITIONAL LIFT. THE JET SETUP AND
TIGHT PRESSURE GRADIENT WILL CREATE BREEZY CONDITIONS ON
WEDNESDAY. MODELS AGREE ON PRECIP BEING OUT OF THE AREA BY 06Z ON
THURSDAY SO LOWERED POPS ACCORDINGLY. BY THURSDAY MORNING THE
FRONT WILL BE OFF THE COAST AND HIGH PRESSURE CENTERED IN THE GULF
WILL DOMINATE THE PATTERN. STRONG CAA ADVECTION BEHIND THE FRONTAL
SYSTEM WILL RETURN MAX TEMPS TO THE MID TO UPPER 50S. LOW TEMPS
WILL BE MUCH COOLER UNDER HIGH PRESSURE AND RADIATIONAL COOLING
THROUGH THE END OF THE WEEK. FRIDAY THE ECMWF AND GFS SHOW A
SHORTWAVE SHIFTING TOWARD THE EAST COAST FROM THE OHIO VALLEY BUT
PRECIP REMAINS WELL NORTH OF THE AREA. COOL HIGH PRESSURE WILL BE
CENTERED OVER THE SOUTHEAST ON SATURDAY.

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
SATELLITE AND OBS INDICATE IFR/MVFR CONDITIONS ACROSS MUCH OF THE
AREA THIS MORNING. THIS WAS EXPECTED...BUT CEILINGS HAVE BEEN LOWER
THAN EXPECTED. RADAR LOOP ALSO SHOWS SOME ISENTROPIC LIFT INDUCED
LIGHT RAIN DEVELOPING ACROSS THE CSRA AND SPREADING NORTHEAST THIS
MORNING.

INCREASING MOISTURE AND ISENTROPIC LIFT WILL OCCUR WITH LIGHT
EAST/NORTHEAST WINDS AT THE SURFACE AND INCREASING SOUTHWEST WINDS
ALOFT THIS MORNING. THIS WEDGE-TYPE PATTERN WILL CONTINUE THROUGH
THE TAF PERIOD. MODELS TRY TO WEAKEN THE WEDGE ACROSS THE EASTERN
CWA THIS AFTERNOON...BUT THEN TRIES TO SETTLE BACK TONIGHT. IFR/MVFR
CONDITIONS WILL PERSIST FOR MUCH OF THE DAY. THE NAM INDICATES LLWS
TOWARD MORNING...BUT BELOW THE CRITERIA FOR INCLUSION IN THE
TERMINAL FORECASTS. CEILINGS ARE EXPECTED TO RISE SOME DURING THE
LATE AFTERNOON...BUT CONDITIONS ARE EXPECTED TO ONCE AGAIN
DETERIORATE DURING THE LATE EVENING/OVERNIGHT HOURS RETURNING TO
MAINLY IFR CONDITIONS UNTIL THE END OF THE TAF PERIOD.

EXTENDED AVIATION OUTLOOK...
PERIODS OF IFR/MVFR CONDITIONS WILL OCCUR DURING TUESDAY MORNING
BECAUSE OF HIGH LOW-LEVEL MOISTURE ASSOCIATED WITH THE SOUTHERLY
FLOW WEST OF OFFSHORE HIGH PRESSURE. A COLD FRONT AND ASSOCIATED
RESTRICTIONS...INCLUDING THUNDER...ARE POSSIBLE WEDNESDAY. STRONG
AND GUSTY SOUTHERLY WINDS ARE EXPECTED WEDNESDAY AHEAD OF THE COLD
FRONT.

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

AREA FORECAST DISCUSSION

NWS COLUMBIA SC

427 AM EST MON JAN 28 2013

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
SATELLITE AND OBS INDICATE IFR/MVFR CONDITIONS ACROSS MUCH OF THE
AREA THIS MORNING. THIS WAS EXPECTED...BUT CEILINGS HAVE BEEN LOWER
THAN EXPECTED.

INCREASING MOISTURE AND ISENTROPIC LIFT WILL OCCUR WITH LIGHT
EAST/NORTHEAST WINDS AT THE SURFACE AND INCREASING SOUTHWEST WINDS
ALOFT. THIS WEDGE-TYPE PATTERN SHOULD CONTINUE THROUGH THE TAF
PERIOD. IFR/MVFR CONDITIONS WILL PERSIST FOR MUCH OF THE DAY. THE
NAM INDICATES LLWS TOWARD MORNING...JUST BELOW THE CRITERIA FOR
INCLUSION IN THE TERMINAL FORECASTS. CEILINGS ARE EXPECTED TO RISE
SOME DURING THE LATE AFTERNOON...BUT CONDITIONS COULD ONCE AGAIN
DETERIORATE TOWARD THE END OF THE TAF PERIOD RETURNING TO IFR/MVFR.

EXTENDED AVIATION OUTLOOK...
PERIODS OF MVFR OR LOWER CONDITIONS MAY OCCUR DURING THE REST OF
MONDAY NIGHT INTO TUESDAY BECAUSE OF HIGH LOW-LEVEL MOISTURE
ASSOCIATED WITH THE SOUTHERLY FLOW WEST OF OFFSHORE HIGH PRESSURE.
A COLD FRONT AND ASSOCIATED RESTRICTIONS...INCLUDING THUNDER...
ARE POSSIBLE WEDNESDAY. STRONG AND GUSTY SOUTHERLY WINDS ARE
EXPECTED WEDNESDAY AHEAD OF THE COLD FRONT.

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

AREA FORECAST DISCUSSION

NWS COLUMBIA SC

151 AM EST MON JAN 28 2013

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
DEVELOPING IN-SITU WEDGE OVER AREA. WEAK ISENTROPIC LIFT TO
THE NORTH HAS CAUSED SOME LIGHT RAIN TO DEVELOP AND MAY AFFECT
NORTHERN COUNTIES OF LANCASTER AND CHESTERFIELD NEXT COUPLE OF
HOURS. GENERALLY...MOST PRECIPITATION SHOULD REMAIN TO THE NORTH
AS UPPER RIDGE AXIS MOVES EAST ACROSS THE REGION. EXPECT ONLY WEAK
FORCING ABOVE WEDGE BUT RUC13 BRINGS WEAK SHORT WAVE THROUGH EARLY
THIS MORNING TO COINCIDE WITH LIGHT RAIN TO THE NORTH.

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
WEDGE IS PRESENTING A CHALLENGING FORECAST FOR MONDAY. RUC13 HAS
A STRONGER BUT STILL WEAK SHORT WAVE RIDING ACROSS UPPER RIDGE BY
THE AFTERNOON. WE HAVE A 20 PERCENT CHANCE OF LIGHT RAIN MUCH OF
THE DAY. LOWERED HIGH TEMPERATURES ABOUT 2-3 DEGREES WITH CLOUD
COVER AND EXPECTED WEDGE CONDITIONS. DID SORT OF A MODEL BLEND
WITH WEDGE HIGH TEMPERATURE TOOL AND MODEL DATA. THIS GAVE HIGHS
AROUND 50 FAR NORTH TO UPPER 50S FAR SOUTH. MONDAY NIGHT WILL
NOT BE AS COLD AS WINDS BECOME SOUTH...LOWS WILL BE IN THE 40S.

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
AS THE HIGH BECOMES CENTERED OFFSHORE AND FLOW BECOMES MORE
SOUTHERLY TEMPS WILL WARM TUESDAY AND WEDNESDAY TO ABOVE NORMAL.
CLOUD COVER WILL INCREASE TUESDAY AHEAD OF AN APPROACHING UPPER
TROUGH. THE ASSOCIATED STRONG COLD FRONT WILL MOVE QUICKLY
THROUGH THE REGION ON WEDNESDAY BRINGING PRECIPITATION TO THE AREA.
HAVE INCLUDED THUNDER DUE TO THE STRONG DYNAMICS OF THE SYSTEM
EVEN THOUGH INSTABILITY APPEARS LIMITED AT THIS TIME. THE CWA WILL
BE IN THE RIGHT ENTRANCE REGION OF A LLJ AND UPPER LEVEL JET AND
PWAT VALUES ARE RELATIVELY HIGH FOR THIS TIME OF YEAR. THE FRONTAL
BOUNDARY WILL PROVIDE ADDITIONAL LIFT. THE JET SETUP AND TIGHT
PRESSURE GRADIENT WILL CREATE BREEZY CONDITIONS ON WEDNESDAY.
MODELS AGREE ON PRECIP BEING OUT OF THE AREA BY 06Z ON THURSDAY SO
LOWERED POPS ACCORDINGLY. BY THURSDAY MORNING THE FRONT WILL BE
OFF THE COAST AND HIGH PRESSURE CENTERED IN THE GULF WILL DOMINATE
THE PATTERN. STRONG CAA ADVECTION BEHIND THE FRONTAL SYSTEM WILL
RETURN MAX TEMPS TO THE MID TO UPPER 50S. LOW TEMPS WILL BE MUCH
COOLER UNDER HIGH PRESSURE AND RADIATIONAL COOLING THROUGH THE END
OF THE WEEK. FRIDAY THE ECMWF AND GFS SHOW A SHORTWAVE SHIFTING
TOWARD THE EAST COAST FROM THE OHIO VALLEY BUT PRECIP REMAINS
WELL NORTH OF THE AREA. COOL HIGH PRESSURE WILL BE CENTERED OVER
THE SOUTHEAST ON SATURDAY.

.AVIATION /07Z MONDAY THROUGH FRIDAY/...
EXPECT VFR CONDITIONS EARLY IN THE TAF PERIOD WITH MVFR CONDITIONS
DEVELOPING TOWARD SUNRISE.

INCREASING MOISTURE AND ISENTROPIC LIFT WILL OCCUR WITH LIGHT WINDS
AT THE SURFACE AND INCREASING SOUTHWEST WINDS ALOFT. THIS WEDGE-TYPE
PATTERN SHOULD CONTINUE THROUGH THE TAF PERIOD. VFR CONDITIONS
SHOULD CONTINUE FOR MUCH OF TONIGHT BECAUSE OF THE INITIAL DRYNESS
BUT EXPECT LOW CLOUDINESS WILL EVENTUALLY DEVELOP. FORECAST
SOUNDINGS INDICATE MVFR OR POSSIBLY IFR CEILINGS DEVELOPING IN THE
09Z-12Z TIME FRAME. AN AVERAGE OF THE GFS AND NAM MOS SUPPORTS MVFR
CEILINGS. BOUNDARY LAYER WINDS SUGGEST STRATUS IS FAVORED OVER FOG.
THE NAM INDICATES LLWS JUST BELOW THE CRITERIA FOR INCLUSION IN THE
TERMINAL FORECASTS.

EXTENDED AVIATION OUTLOOK...
PERIODS OF MVFR OR LOWER CONDITIONS MAY OCCUR DURING THE REST OF
MONDAY NIGHT INTO TUESDAY BECAUSE OF HIGH LOW-LEVEL MOISTURE
ASSOCIATED WITH THE SOUTHERLY FLOW WEST OF OFFSHORE HIGH PRESSURE. A
COLD FRONT AND ASSOCIATED RESTRICTIONS...INCLUDING THUNDER...ARE
POSSIBLE WEDNESDAY. STRONG AND GUSTY SOUTHERLY WINDS ARE EXPECTED
WEDNESDAY AHEAD OF THE COLD FRONT.

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

AREA FORECAST DISCUSSION

NWS LINCOLN IL

906 PM CST TUE JAN 29 2013

.DISCUSSION...
ISSUED 905 PM CST TUE JAN 29 2013

INITIAL WIND SHIFT HAS PUSHED THROUGH ABOUT 3/4 OF THE CWA...
CURRENTLY EXTENDING FROM ABOUT EFFINGHAM TO DANVILLE. TEMPERATURES
STILL IN THE 60-65 RANGE AHEAD OF THIS AREA...WITH SOME GRADIENT
WIND GUSTS OF 35-40 MPH. THE MAIN COLD FRONT WAS LOCATED JUST EAST
OF THE IOWA BORDER...WHERE TEMPERATURES FALL INTO THE 30S. HAVE
HAD SOME WAVES OF LOW PRESSURE RIDING ALONG THE FRONT...WHICH HAS
SLOWED DOWN ITS PASSAGE SOMEWHAT...BUT LATEST MODEL GUIDANCE STILL
INDICATES IT SHOULD START MOVING THROUGH THE WESTERN CWA LATE
TONIGHT.

MAIN CONCERN REMAINS WITH THE RAIN TONIGHT AND THE FLOOD WATCH.
EVENING UPPER AIR SOUNDING FROM LINCOLN HAD PRECIPITABLE WATER
VALUES OF 1.43 INCHES...WHICH LOCAL RESEARCH INDICATES IS A RECORD
FOR JANUARY IN THIS AREA. SO FAR...HAVE SEEN LITTLE OR NO RAIN IN
THE FAR SOUTHEAST CWA...BUT THAT SHOULD BE INCREASING SHORTLY AS A
NARROW CONVECTIVE LINE FROM SALEM SOUTHWEST INTO MISSOURI MOVES
QUICKLY EASTWARD. RAP MODEL SHOWS THE SAME HIGH PWAT VALUES
AFFECTING SOUTHEAST ILLINOIS OVER THE NEXT SEVERAL HOURS...SO SOME
HEAVY RAIN THERE IS STILL LIKELY. THE WESTERN HALF OF THE CWA HAS
SEEN AMOUNTS OVER AN INCH COMMON WEST OF A BLOOMINGTON TO
JACKSONVILLE LINE...WITH SOME 1.5 TO 2 INCH TOTALS TOWARD THE
ILLINOIS RIVER VALLEY. HAVE KEPT THE FLOOD WATCH IN PLACE FOR
NOW OVER THE ENTIRE AREA...BUT HAVE SOME CONCERNS ABOUT THE
NORTHWEST CWA...AS REGIONAL RADAR MOSAICS SHOW THE HEAVIEST AXIS
OF RAIN FURTHER TO THE EAST. WILL WATCH THIS FOR A COUPLE MORE
HOURS BEFORE DECIDING WHETHER OR NOT TO TRIM DOWN THE WATCH AREA.

UPDATED ZONES/GRIDS HAVE BEEN SENT.

GEELHART

.AVIATION...
ISSUED 545 PM CST TUE JAN 29 2013

NARROW LINE OF THUNDERSTORMS EXPECTED TO MOVE INTO KBMI/KDEC OVER
THE NEXT HOUR OR SO...AND REACH KCMI AROUND 0230Z. HAVE SEEN SOME
GUSTS OF 30-40 KNOTS WITH THE LINE...WITH WINDS TRENDING TO THE
NORTHWEST IN THE LARGER RAIN SHIELD THAT EXTENDS FURTHER WEST.
CEILINGS HAVE RISEN INTO THE VFR RANGE IN A NARROW AREA BEHIND THE
LINE TO NEAR THE MISSISSIPPI RIVER...BUT ARE EXPECTED TO DROP BACK
DOWN TO IFR LEVELS LATER THIS EVENING. A PERIOD OF MORE SHOWERY
PRECIPITATION IS EXPECTED BETWEEN MIDNIGHT AND 12Z WORKING ITS WAY
WEST TO EAST. HOWEVER...ANOTHER AREA OF PRECIPITATION WILL SET UP
OVER MISSOURI/IOWA LATE IN THE NIGHT AND LIFT NORTHEAST. FORECAST
SOUNDINGS SHOWING RAIN SWITCHING TO SNOW WEDNESDAY...WITH SOME
POTENTIAL FOR SLEET FOR AN HOUR OR TWO AROUND KSPI/KDEC. NORTHWEST
WINDS EXPECTED TO RAMP UP WEDNESDAY MORNING AND GUST FROM 25-30
KNOTS OR SO FROM LATE MORNING THROUGH MUCH OF THE AFTERNOON.

GEELHART

.PREV DISCUSSION...
ISSUED 320 PM CST TUE JAN 29 2013

MAIN CONCERN THIS FORECAST PACKAGE CONTINUES TO INVOLVE THE
POTENTIAL HEAVY RAIN/FLOOD WATCH EVENT FOR TONIGHT...WHEN RAIN
WILL CHANGE OVER TO SNOW...AND FALLING TEMPS IN THE SHORT TERM.

ALL MODELS IN GOOD AGREEMENT WITH OVERALL UPPER LEVEL PATTERN
THROUGH THE SHORT TERM...AND WITH THE SFC FEATURES AND MOVEMENTS
THROUGH FRIDAY. EXTENDED MODELS HAVE TRENDED INTO BETTER AGREEMENT
IN THE EXTENDED WITH SFC FEATURES AS WELL. THEREFORE CONFIDENCE IS
ABOVE AVERAGE FOR THIS FORECAST PACKAGE.

SHORT TERM...TONIGHT THROUGH FRIDAY

A SFC LOW IN CENTRAL OKLAHOMA IS FORECAST TO CONTINUE TO MOVE
NORTHEAST ALONG A FRONTAL SYSTEM STRETCHING FROM WI...THROUGH
NORTHWESTERN IL...THROUGH MO AND INTO OK. THIS LOW WILL MOVE
ACROSS CENTRAL ILLINOIS THIS EVENING AND INTO SOUTHERN MICH JUST
AFTER MIDNIGHT. THE UPPER LEVEL TROUGH ASSOCIATED WITH THIS SFC
SYSTEM WILL REMAIN BACK IN THE CENTRAL US AND NOT MOVE INTO AND
THROUGH THE CWA UNTIL TOMORROW EVENING. THE TROUGH MOVES
THROUGH...BUT THEN BROADENS AS ANOTHER SMALLER AND LESS INTENSE SFC
LOW MOVES OUT OF THE PLAINS AND THROUGH SOUTHERN IL THURSDAY. THIS
WILL PUSH THROUGH QUICKLY AND THEN COLD HIGH PRSS MOVES BACK INTO
THE AREA FOR THUR NIGHT AND FRIDAY. SHOWERS AND THUNDERSTORMS WITH
HEAVY RAINFALL ARE FORECAST TO CONTINUE TO MOVE ACROSS THE CWA
TONIGHT. STORMS WILL BE MOVING VERY QUICKLY TO THE NORTHEAST THIS
EVENING AND COULD BE SEVERE AT TIMES WITH DAMAGING WINDS. TORNADO
WATCHES ARE ONGOING TO THE SOUTHWEST OF THE AREA...AND OUR CWA MAY
HAVE TO BE INCLUDED LATER THIS AFTERNOON AND INTO THIS EVENING IF
THE STORMS SOUTHWEST OF THE AREA MAINTAIN THEIR STRENGTH AS THEY
MOVE NORTHEAST. TOMORROW...THE PCPN WILL BEGIN TO CHANGE TO ALL
SNOW AS MUCH COLDER AIR ADVECTS INTO THE AREA. MODELS ARE FORECASTING
AN AREA OF DEFORMATION SNOW TO SETUP WEST OF THE TRACK OF THE SFC
LOW TOMORROW WITH THE HIGHEST ACCUMULATING SNOW STAYING NORTHWEST
OF THE IL RIVER. LOOKING FOR ABOUT AN INCH ALONG A RUSHVILLE TO
BLOOMINGTON LINE WITH UP TO AROUND 1.5 INCHES AROUND GALESBURG.
AMOUNTS OF A HALF AN INCH OR LESS WILL BE ALONG I-72. AS THIS
SYSTEM PULLS EAST AND NORTHEAST...A SLIGHT CHANCE OF SNOW WILL
CONTINUE ACROSS THE EXTREME NORTHEAST OF THE CWA WED NIGHT.

WITH THE TROUGH BROADENING...A SFC LOW WILL MOVE OUT OF THE PLAINS
AND THROUGH SOUTHERN IL THURSDAY. THIS WILL BRING A SLIGHT CHANCE
OF MORE SNOW TO THE WHOLE CWA...MAINLY THUR AFTERNOON. BEYOND
THIS...COLD ARCTIC HIGH PRSS WILL DROP INTO THE REGION WITH DRY
AND VERY COLD WEATHER FOR THUR NIGHT AND FRIDAY.

LOWS TONIGHT WILL BE CLOSE TO MIDNIGHT AND HIGHS TOMORROW WILL
PROBABLY BE JUST AFTER MIDNIGHT TONIGHT. TEMPS WILL THEN GRADUALLY
FALL TOMORROW THROUGH TOMORROW NIGHT. THEN COLDER AIR WILL ADVECT
INTO THE REGION FOR THUR NIGHT AND FRIDAY...WITH TEMPS AROUND ZERO
IN THE NORTHWEST TO IN THE LOWER TEENS IN THE SOUTHEAST...FOR THUR
NIGHT. FRI TEMPS WILL BE WELL BELOW NORMAL FOR FRIDAY AS
WELL...NOT REACHING ABOVE FREEZING ANYWHERE IN THE CWA.

LONG TERM...FRIDAY NIGHT THROUGH TUESDAY

MODELS HAVE ANOTHER SFC LOW DROPPING ACROSS NORTHERN IL FRIDAY
NIGHT...SPREADING SOME LIGHT SNOW ACROSS THE NORTHEASTERN HALF OF
THE CWA. THIS CLIPPER SYSTEM WILL BE QUICK SO ACCUMULATIONS WILL
BE VERY LIGHT. BEYOND THIS...ANOTHER WEAK SYSTEM IS FORECAST TO
MOVE ACROSS THE AREA WITH LIGHT PCPN MON AND MONDAY NIGHT. FOR NOW
WILL KEEP ONLY SLIGHT CHC OF POPS IN THE FORECAST...WHICH WILL NOT
BE MENTIONED IN THE WORDED FORECAST. OTHER THAN THESE TWO
SYSTEMS...REMAINDER OF THE LONG TERM PERIODS WILL BE DRY.

TEMPS WILL START COLD BUT THEN WARM QUICKLY FOR THE WEEKEND AND
INTO THE BEGINNING OF NEXT WEEK. WARMEST DAY LOOKS TO BE MONDAY
WITH TEMPS 5+ DEGREES ABOVE NORMAL.

AUTEN

.ILX WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH UNTIL 6 AM CST WEDNESDAY FOR ILZ027>031-036>038-
040>057-061>063-066>068-071>073.

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

902 PM CST TUE JAN 29 2013

.MESOSCALE DISCUSSION...
240 PM CST

THE THREAT FOR HEAVY RAIN DEVELOPING AND POSSIBLY A COUPLE SEVERE
STORMS CONTINUES.

THE LATEST HAND ANALYSIS PLACES THE COLD FRONT JUST PAST THE
MISSISSIPPI RIVER IN NORTHWEST IL WITH A SUBTLE PRE-FRONTAL
TROUGH FROM JUST EAST OF ROCKFORD SOUTH TOWARD PEORIA. THIS PRE-
FRONTAL TROUGH DOES HAVE AN INSTABILITY PLUME AIDED BY LOW TO MID
60S TEMPERATURES...AND LOW-LEVEL CAPE IS ANALYZED NEAR 100 J/KG
WITH AROUND 300-500 J/KG OF SURFACE-BASED CAPE. THIS INSTABILITY
THOUGH IS NOT LINING UP WITH ANY GREAT STORM ACTIVITY.

SATELLITE AND RADAR TRENDS SHOW THAT A LARGE SWATH OF RAIN HAS
EXPANDED FROM MO NORTHEAST THROUGH WESTERN IL AND SOUTHERN
WI...STABILIZING MUCH OF THAT AREA. AT THE FRONT EDGE OF
THIS...NEAR THE PRE-FRONTAL TROUGH...MORE CONVECTIVE-LIKE SHOWERS
ARE PRESENT. THAT CONVECTION ON THE ILX RADAR HAS STRUGGLED TO
BECOME WELL-DEFINED AND HAS MORE OF A QUASI-LINEAR MUSHY LOOK
RIGHT NOW. LIGHTNING HAS BEEN SOMEWHAT SPORADIC AND REALLY HAS
ONLY BEEN SEEN IN THE CLUSTER THAT IS NEARING CHICAGO...POSSIBLY
ASSOCIATED WITH A WARM AIR ADVECTION FLANK AHEAD OF THE SYSTEM.
OVERALL THE TREND HAS BEEN SLIGHTLY DOWN WITH NO LOCAL STORMS
APPROACHING SEVERE LIMITS...AND A FEW 30-37 KT GUSTS OBSERVED. AT
THIS TIME...IT REMAINS QUITE MARGINAL FOR SEVERE WEATHER AND MAY
CONTINUE TO THROUGH MUCH OF THE AFTERNOON AS NO IMMEDIATE STRONG
IMPULSES UPSTREAM ARE EVIDENT.

TOWARD SUNSET AND INTO THIS EVENING...AREAS ALONG AND EAST OF I-55
WILL REMAIN FAVORED FOR STORM ACTIVITY ON THE NOSE OF AN
INCREASING LOW LEVEL JET AND JUST MORE IMPROVED OVERALL FORCING.
EXPLICIT CONVECTIVE MODELS AGREE THIS AREA WILL BE UNDER SOME
STRONGER ACTIVITY THIS EVENING...BUT WHETHER THAT IS TO THE
LIMITS TO FLIRT WITH SEVERE IS LOW CONFIDENCE. THE FORECAST DCAPE
DOES INCREASE TO AROUND 400-500 J/KG ON THE NAM AND THE LOW-LEVEL
SHEAR/HELICITY REMAINS HIGH IN THE STRONG ATMOSPHERIC WINDS. THIS
MAY END UP BEING OUR BEST...ALBEIT NARROW WINDOW FOR SEVERE
WEATHER.

HEAVY RAIN REMAINS THE PRIMARY POTENTIAL HAZARD. WHILE IT IS A
QUASI- LINEAR MUSHY LOOK RIGHT NOW...RAINFALL RATES ARE LIKELY
VERY EFFICIENT IN ANY ACTIVITY AND WILL CONTINUE AS SUCH LATE THIS
AFTERNOON INTO TONIGHT. A PERSISTENT FOCUS IS SEEN IN THE RAP AND
NAM FORECASTS AS DEEP LAYER MOISTURE CONVERGENCE FURTHER INCREASES
TONIGHT AS THE UPPER TROUGH INCHES EASTWARD. WIDESPREAD RAINFALL
AMOUNTS OF ONE TO TWO AND A HALF INCHES LOOK LIKELY...WITH
POTENTIALLY THE HIGHER END AMOUNTS BEING WIDESPREAD. WITH MUCH OF
THIS GOING TOWARD RUNOFF...AT LEAST LOCALIZED PONDING TO POSSIBLE
FLOODING WILL BE LIKELY.

MTF

.DISCUSSION...
318 PM CST

SHORT TERM...REST OF TODAY THROUGH WEDNESDAY NIGHT...
FOR HEADLINES...KEPT FLOOD WATCH AS IS AND NO WINTER HEADLINES ARE
EXPECTED AT THIS TIME.

A DEEP TROUGH LIES ACROSS THE WESTERN US WITH ITS AXIS OVER THE
GREAT PLAINS...WHILE A SURFACE LOW IS OVER ONTARIO. THE SURFACE
LOWS COLD FRONT EXTENDS FROM THE LOW THROUGH CENTRAL WI TO ALONG THE
MISSISSIPPI RIVER...AND IT IS SLOWLY MAKING ITS WAY INTO WESTERN
IL. THE TEMPERATURE GRADIENT ACROSS THE FRONT IS RATHER IMPRESSIVE
WITH 60 DEGREES IN PERU IL AND 38 DEGREES IN OTTUMWA IA...WITH JUST
176 MILES BETWEEN THE TWO CITIES. SHOWERS AND THUNDERSTORMS HAVE
SPREAD INTO NORTHERN IL AHEAD OF THE COLD FRONT AND WILL CONTINUE TO
SPREAD ACROSS THE CWA THIS AFTERNOON/EARLY EVENING. INDIVIDUAL CELLS
HAVE BEEN CLOCKED AT 50-60 KT MOVING FROM THE SOUTHWEST TO THE
NORTHEAST. SEVERE STORMS ARE STILL POSSIBLE THIS AFTERNOON...FOR
MORE INFORMATION ON THE SEVERE WEATHER OUTLOOK AND RELATED
PARAMETERS PLEASE SEE THE MESOSCALE DISCUSSION ABOVE.

PWAT VALUES WILL BE IN EXCESS OF 1-1.5 INCHES THIS AFTERNOON/EVENING
WITH DEWPOINTS CURRENTLY IN THE UPPER 50S TO LOW 60S FALLING
OVERNIGHT. FLOW THROUGHOUT THE ATMOSPHERIC COLUMN IS ROUGHLY
PARALLEL TO THE FRONT WHICH WILL INHIBIT THE FRONT FROM RAPIDLY
PROGRESSING THROUGH THE CWA. TRAINING WILL ALSO BECOME AN ISSUE
ALONG THE FRONT ALLOWING FOR IMPRESSIVE RAIN TOTALS. THE UPPER
LEVEL JET STRETCHES FROM TEXAS THROUGH MINNESOTA BEFORE CURVING
TOWARD QUEBEC. THE RIGHT JET ENTRANCE REGION LIES OVER SOUTHWEST
WI/NORTHWEST IL ALMOST COLLOCATED WITH THE FRONT WHICH WILL CONTINUE
TO SUPPORT THUNDERSTORM AND SHOWER FORMATION. BASED ON WHAT HAS
PASSED OVER THE OFFICE THIS AFTERNOON...SOME OF THESE SHOWERS/STORMS
WILL PRODUCE BRIEF INTENSE DOWNPOURS. THE JET AND FRONT CONTINUE
ACROSS THE CWA TONIGHT WITH THE SOUTHERN JET STREAKS LEFT EXIT
REGION POSSIBLY COUPLING WITH THE FRONT. AS SUCH EXPECTING PERIODS
OF HEAVY RAIN TO CONTINUE OVERNIGHT. WHEN ALL IS SAID AND
DONE...THINKING 1.5-2.5 INCHES OF RAIN ARE POSSIBLE ACROSS THE
AREA. LOCALLY HIGHER AMOUNTS ARE CERTAINLY POSSIBLE.

QUICKLY CHECKING THE OFFICES SOIL TEMPS...2 AND 4 INCHES BELOW THE
SURFACE ARE ABOVE FREEZING AT 35 DEGREES WHILE 8 INCHES IS STILL
FROZEN AT 27 DEGREES. AS SUCH EXPECTING PONDING OF WATER IN THE
TYPICAL LOW LYING SPOTS...SINCE THE SOIL WILL NOT BE ABLE TO TAKE IN
AS MUCH WATER AS USUAL. THEREFORE MADE NO ADJUSTMENTS TO THE FLOOD
WATCH.

TEMPS WILL BEGIN TO FALL OVERNIGHT WITH LOWS IN THE LOW 30S NEAR RFD
TO ARND 50 NEAR RENSSELAER.

WEDNESDAY...
TEMPS WILL CONTINUE TO FALL WEDNESDAY MORNING WITH PRECIP
TRANSITIONING TO SNOW AS A SWATH OF MOISTURE ASSOCIATED WITH THE 700
MB LOW SURGES NORTH. SOUNDINGS INDICATE A BRIEF PERIOD OF SLEET IS
POSSIBLE DURING THE TRANSITION BUT NOT EXPECTING ANY SIGNIFICANT
SLEET ACCUMULATION. EXPECTING AREAS AROUND RFD TO CHANGE OVER TO
SNOW BEFORE 8AM...CHICAGO AROUND 3PM...AND NW INDIANA 4-6PM.

FOR SNOW TOTALS...EXPECTING THE HIGHEST TOTALS IN FAR NW IL IN
WINNEBAGO AND OGLE COUNTIES. THE NAM IS MUCH MORE EXCITED THAN THE
GFS ABOUT THE SNOW POTENTIAL BUT BOTH MODELS SHOW THE SAME SET UP
THAT IS FAVORABLE FOR MESOSCALE SNOW BANDS. 850-700 MB
FRONTOGENESIS MOVES OVER NW IL/E IA EARLY WEDNESDAY MORNING WITH EPV
VALUES BELOW 0 JUST ABOVE IT...INDICATING LOCALIZED INTENSE FORCING
AND SYMMETRIC INSTABILITY. HOWEVER EXPECTING TEMPS TO BE ABOVE
FREEZING AT THIS POINT. THE FRONTOGENESIS AND INSTABILITY SHIFT
EASTWARD THROUGH THE MORNING AND THEN WEAKEN AFTER NOON. THE LEFT
JET EXIT REGION OF THE UPPER LEVEL JET WILL ALSO BE OVER NORTHERN IL
THROUGH WEDNESDAY AFTERNOON SO SYNOPTIC-SCALE LIFT SHOULD NOT BE AN
ISSUE.

WHILE MESOSCALE BANDS OF RAIN OR SNOW ARE VERY LIKELY
TOMORROW...THESE FEATURES ARE HARD TO PINPOINT EVEN THIS FAR OUT.
THEREFORE WENT WITH 3-5 INCHES OF SNOW OVER WINNEBAGO AND OGLE
COUNTIES TOMORROW...BUT THIS NUMBER COULD EASILY BE HIGHER IF A BAND
OF SNOW SETS UP. THE BIG QUESTIONS ARE WILL THE BEST FORCING ALIGN
WITH SNOW OR RAIN...HOW LONG WILL THE FORCING LAST...AND WHERE WILL
THE MESOSCALE BAND SET UP.

AS MENTIONED BEFORE...THE FRONTOGENESIS WEAKENS AND STABILITY
INCREASES IN THE AFTERNOON AS THE SNOW SPREADS ACROSS THE REST OF
THE CWA. SO INTENSE MESOSCALE BANDS ARE NOT AS LIKELY...BUT FORCING
FROM THE UPPER LEVEL JET STILL LOOKS FAVORABLE FOR A LITTLE SNOW. AS
SUCH EXPECTING 1 TO 3 INCHES OF SNOW ACROSS BOONE AND MCHENRY
COUNTIES...AND THEN AN INCH OR LESS EVERYWHERE ELSE. SNOW ENDS FROM
WEST TO EAST...WITH NO SNOW EXPECTED AFTER MIDNIGHT ON WEDNESDAY.

TEMPS CONTINUE TO TUMBLE TO THE TEENS OR SINGLE DIGITS WEDNESDAY
NIGHT. WINDS 20-25 MPH WITH GUSTS UP TO 30 MPH SLOWLY WEAKEN
OVERNIGHT...BUT EXPECTING WINDCHILLS TO BE BTWN 1 AND -10.

JEE

EXTENDED PERIOD...THURSDAY THROUGH TUESDAY...

MAIN FORECAST CONCERN IN EXTENDED PERIOD DEALS WITH REINFORCEMENT OF
ARCTIC COLD THURSDAY NIGHT/FRIDAY...AND THE POTENTIAL FOR LIGHT SNOW
FRIDAY NIGHT/SATURDAY WITH A COUPLE CLIPPER-TYPE SYSTEMS ON THE BACK
SIDE OF THE RETREATING LOW LEVEL COLD AIR.

MEDIUM RANGE GUIDANCE APPEARS TO BE IN GOOD AGREEMENT AT THE START
OF THE PERIOD THURSDAY MORNING...WITH DEEP SURFACE LOW LIFTING
NORTHEAST ACROSS EASTERN QUEBEC AND DEEP UPPER LEVEL TROUGH ACROSS
MUCH OF EASTERN NORTH AMERICA. ALL OF THE GLOBAL MODELS DEPICT
ANOTHER STRONG SHORT WAVE DIGGING SOUTHEAST ACROSS THE UPPER
MISSISSIPPI VALLEY AND WESTERN GREAT LAKES REGION THROUGH THE DAY...
ACCOMPANIED BY A STRONG PUSH OF COLD ARCTIC AIR WITH 850 MB TEMPS OF
-22 TO -24 C MOVING INTO THE CWA BY THURSDAY EVENING. MODEL
SOUNDINGS AND TIME/HEIGHT SERIES INDICATE DRY MID/UPPER LEVELS AHEAD
OF THIS DIGGING SHORT WAVE...WITH MODEL GENERATED QPF LIMITED TO THE
MID/LOWER MISSOURI RIVER VALLEY INTO THE LOWER OHIO VALLEY THURSDAY
AFTERNOON AND EVENING...THE COMBINATION OF DIGGING VORT...COLD
ADVECTION WITH VERY COLD ARCTIC AIR...AND RELATIVELY MOIST LOW
LEVELS ALL POINT TO THE POTENTIAL FOR AT LEAST SOME FLURRIES ACROSS
THE FORECAST AREA THURSDAY AFTERNOON/EVENING. TEMPS...WHICH SHOULD
ONLY TOP OUT IN THE MID TEENS NORTH AND LOWER 20S SOUTH AFTER
WEDNESDAYS COLD FRONT...SHOULD EASILY FALL TO AROUND/BELOW ZERO
ACROSS NORTH CENTRAL IL BY SUNRISE FRIDAY AND TO PERHAPS THE LOW
POSITIVE SINGLE DIGITS ACROSS THE SOUTH WITH STRONG LOW LEVEL COLD
ADVECTION THURSDAY NIGHT. HAVE TRENDED COLDER TOWARD THE 00Z GEFS
MOS...AND A FEW DEGREES BELOW THAT AROUND ROCKFORD. THIS MAY NOT BE
COLD ENOUGH ESPECIALLY IF SIGNIFICANT SNOW PACK IS IN PLACE AFTER
WEDNESDAY. WINDS SHOULD REMAIN BLUSTERY ESPECIALLY IN THE EVENING
WITH THE ENHANCED GRADIENT TO THE EAST OF THE CANADIAN HIGH BUILDING
SOUTHEAST THROUGH THE PLAINS...SUPPORTING WIND CHILLS -10 TO -20 F
OVERNIGHT.

THE MID-LEVEL SHORT WAVE TROUGH AXIS IS PROGGED TO MOVE OFF TO THE
SOUTHEAST OF THE FORECAST AREA EARLY FRIDAY MORNING...WITH FAIRLY
STRONG HEIGHT RISES DEVELOPING IN ITS WAKE. COLD SURFACE HIGH
PRESSURE CENTER WILL CONTINUE TO PUSH SOUTHEAST THROUGH THE LOWER
OHIO VALLEY INTO TENNESSEE BY EVENING. CORE OF THE COLDEST AIR WILL
SHIFT OFF TO THE EAST/SOUTHEAST BY AFTERNOON...THOUGH COLD MORNING
START AND SHALLOW MIXED LAYER BENEATH SUBSIDENCE INVERSION WILL
ALLOW ONLY MARGINAL MODERATION OF TEMPS AT THE SURFACE. HAVE ALSO
TRENDED COLDER WITH MAXES FRIDAY TOWARD COLDER GFS/GEFS MOS NUMBERS.

NORTHERN EXTENT OF SURFACE RIDGE AXIS MOVES ACROSS THE CWA FRIDAY
EVENING...WITH WARM ADVECTION ALREADY DEVELOPING ON THE WESTERN
PERIPHERY OF THE RETREATING LOW LEVEL COLD AIR DOME. WITH NORTHWEST
FLOW ALOFT ON THE BACK SIDE OF THE DEPARTING LONG-WAVE UPPER TROUGH
THIS SETS THE STAGE FOR A COUPLE OF MODEST SHORT WAVES TO BRING A
COUPLE POTENTIAL PERIODS OF LIGHT SNOW TO THE REGION FRIDAY NIGHT
AND SATURDAY. ECMWF/GFS 12Z RUNS REMAIN IN FAIRLY GOOD AGREEMENT IN
DEVELOPING LIGHT QPF ACROSS THE AREA WITH A WEAK SURFACE LOW MOVING
ACROSS NORTHERN ILLINOIS SATURDAY. UPPER JET CORE THEN SHIFTS SLOWLY
EAST/NORTHEAST ACROSS THE NORTHERN/CENTRAL GREAT LAKES SATURDAY
NIGHT...AS HIGH PRESSURE RIDGE MOVES ACROSS THE REGION THROUGH
SUNDAY. WITH COLD CORE OF UPPER TROUGH OFF TO THE EAST...TEMPS
MODERATE BACK TO MORE SEASONABLE LEVELS SATURDAY (MID-UPPER 20S) AND
PERHAPS A BIT ABOVE (30S) SUNDAY AS WINDS SHIFT SOUTH IN THE
AFTERNOON WEST OF THE RIDGE AXIS. MODERATION LOOKS TO CONTINUE
MONDAY AS ECMWF/GFS REMAIN IN GOOD AGREEMENT IN TAKING AN AREA OF
SURFACE LOW PRESSURE NORTH OF THE CWA ACROSS MN/WI. DRY HIGH
PRESSURE BLOCKS MOISTURE RETURN FROM THE SOUTH FOR THE MOST PART...
WITH NEXT CHANCE OF ORGANIZED PRECIP OCCURRING WITH THE COLD FRONT
ASSOCIATED WITH THIS LOW MONDAY/MONDAY NIGHT...AND MAINLY ACROSS THE
SOUTHEASTERN CWA. GEM MEANWHILE DURING THIS PERIOD BECOMES A COLD
OUTLIER...WITH CONSISTENT ECMWF/GFS SOLUTIONS FAVORED AT THIS
DISTANCE. THIS WOULD INDICATE COOLER/SEASONAL TEMPS RETURN TUESDAY.

RATZER

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 03Z...

* PERSISTENT LIGHT TO OCCASIONALLY MODERATE RAIN THROUGH LATE
TOMORROW MORNING.

* PREVAILING IFR CIGS/VIS FROM LATE EVENING THROUGH EARLY TOMORROW
AFTERNOON.

* WIND SHIFT TO NLY-NNELY ARND 04Z THEN BCCKING TO NWLY TOMORROW
MORNING.

KREIN

//DISCUSSION...UPDATED 00Z...

THE LINE OF HEAVIEST RAIN AND SCATTERED THUNDERSTORMS HAS PUSHED
EAST OF ALL TERMINALS EXCEPT GYY...WHICH WILL BE IMPACTED
SHORTHLY. WHILE THE HEAVIEST RAIN AND THUNDERSTORM POTENTIAL IS
ALONG THIS LINE...THERE IS STILL A SMALL LINGERING CHANCE OF SOME
ISOLATED THUNDER FOR A SHORT TIME FOLLOWING THE PASSAGE OF THIS LINE.

FOR THE REMAINDER OF THE EVENING AND OVERNIGHT...WIDESPREAD RAIN
AND IFR CIGS WILL COVER THE AREA AND IMPACT ALL TERMINALS. WINDS
WILL SHIFT TO NLY-NNELY EARLY THIS EVENING FOLLOWING THE PASSAGE
OF THE COLD FRONT...BUT IT WILL BE QUITE SOME TIME UNTIL THE
COOLER...DRIER AIR FILTERS OVER THE REGION. RAIN SHOULD BEGIN TO
TAPER OFF TOMORROW MORNING AND TRANSITION OVER TO LIGHT SNOW BY
EARLY AFTERNOON. THE IFR CIGS WILL PERSIST UNTIL THE DRIER AIR
ASSOCIATED WITH THE COOLER AIRMASS OVERSPREADS THE REGION. SO...BY
EARLY TOMORROW AFTERNOON...EXPECT THE BIGGEST IMPROVEMENT TO
FLIGHT CONDITIONS...IMPROVING TO MVFR...BUT AT THAT POINT...LIGHT
SNOW SHOULD BEGIN WITH SOME ACCUMULATION POSSIBLE.

KREIN

//ORD AND MDW CONFIDENCE...UPDATED 03Z...

* HIGH CONFIDENCE IN PCPN TRENDS.

* MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS.

* MEDIUM TO HIGH CONFIDENCE IN CIG/VIS TRENDS...BUT LOWER
CONFIDENCE IN EXACT TIMING OF IMPROVEMENT.

KREIN

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

THURSDAY...CHANCE OF FLURRIES IN THE AFTERNOON/EVENING. MVFR CIGS
POSSIBLE. WEST WINDS GUSTING TO 25-30KT.

FRIDAY...VFR EARLY. CHANCE OF SNOW WITH MVFR CIGS/VIS OVERNIGHT.

SATURDAY...CHANCE OF SNOW WITH MVFR CIGS/VIS EARLY...THE VFR
OVERNIGHT.

SUNDAY...VFR. WX NIL.

MONDAY...SLIGHT CHANCE RAIN/SNOW. MVFR CIGS/VIS POSSIBLE.

KREIN

.MARINE...
1248 PM CST

SEVERAL WAVES OF LOW PRESSURE WILL RIDE UP A SLOW MOVING COLD
FRONT TONIGHT THROUGH WEDNESDAY AFTERNOON...AS THE FRONT TRAVERSES
LAKE MICHIGAN. STRONG SOUTH TO SOUTHWEST WINDS AHEAD OF THE
FRONT HAVE PROMPTED A SMALL CRAFT ADVISORY FOR THE IL AND IN
NEARSHORE. WINDS WILL SUBSIDE AS THE FRONT APPROACHES THE ILLINOIS
WATERS LATE THIS AFTERNOON...AND THE INDIANA WATERS THIS EVENING.
AREAS OF DENSE FOG ARE POSSIBLE INTO THIS EVENING...MAINLY OVER
THE SOUTH HALF OF THE LAKE...AS UNSEASONABLY MILD AND HUMID AIR
MOVES OVER THE CHILLY WATER.

BEHIND THE COLD FRONT...NORTHWEST WINDS WILL RAMP UP AS THE FINAL
WAVE OF LOW PRESSURE MOVES INTO EASTERN CANADA AND
INTENSIFIES...WHILE STRONG HIGH PRESSURE BUILDS INTO THE NORTHERN
PLAINS. GALE FORCE WINDS WILL DEVELOP BY MID MORNING WEDNESDAY AND
SLOWLY DIMINISH BELOW GALE FORCE THURSDAY MORNING. THE GALE WATCH
WILL BE UPGRADED TO A GALE WARNING WITH THE 300 PM GLFLM ISSUANCE.

STRONG WEST TO NORTHWEST WINDS WILL CONTINUE THROUGH FRIDAY BEFORE
DIMINISHING THIS WEEKEND AS THE HIGH PRESSURE SETTLES OVER THE
SOUTHEAST. FREEZING SPRAY IS LIKELY WEDNESDAY NIGHT AND THURSDAY
DUE TO THE COMBINATION OF STRONG WINDS...LARGE WAVES...AND ARCTIC
AIR OVER THE LAKE.

ALLSOPP

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-ILZ011-
ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-ILZ023-
ILZ032-ILZ033-ILZ039 UNTIL 4 AM WEDNESDAY.

IN...FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 4 AM
WEDNESDAY.

LM...DENSE FOG ADVISORY...LMZ080-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-
LMZ740-LMZ741-LMZ742-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878 UNTIL 10 PM TUESDAY.

GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...9 AM WEDNESDAY TO 6 AM
THURSDAY.

SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 4 AM WEDNESDAY.

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

613 PM CST TUE JAN 29 2013

.MESOSCALE DISCUSSION...
240 PM CST

THE THREAT FOR HEAVY RAIN DEVELOPING AND POSSIBLY A COUPLE SEVERE
STORMS CONTINUES.

MTF

.DISCUSSION...
318 PM CST

SHORT TERM...REST OF TODAY THROUGH WEDNESDAY NIGHT...
FOR HEADLINES...KEPT FLOOD WATCH AS IS AND NO WINTER HEADLINES ARE
EXPECTED AT THIS TIME.

TEMPS WILL BEGIN TO FALL OVERNIGHT WITH LOWS IN THE LOW 30S NEAR RFD
TO ARND 50 NEAR RENSSELAER.

TEMPS CONTINUE TO TUMBLE TO THE TEENS OR SINGLE DIGITS WEDNESDAY
NIGHT. WINDS 20-25 MPH WITH GUSTS UP TO 30 MPH SLOWLY WEAKEN
OVERNIGHT...BUT EXPECTING WINDCHILLS TO BE BTWN 1 AND -10.

JEE

EXTENDED PERIOD...THURSDAY THROUGH TUESDAY...

RATZER

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 00Z...

* CHANCE OF THUNDERSTORMS FOR ANOTHER HOUR OR SO AS LEADING EDGE
OF WIDESPREAD RAIN PUSHES THROUGH THE AREA.

* PERSISTENT MODERATE TO OCCASIONALLY HEAVY RAIN UNTIL AROUND 03Z.

* CIGS LOWERING TO PREVAILING IFR FROM LATE EVENING THROUGH EARLY
TOMORROW AFTERNOON.

* WIND SHIFT TO NLY-NNELY ARND 03Z FOLLOWING FRONTAL PASSAGE,

KREIN

//DISCUSSION...UPDATED 00Z...

KREIN

//ORD AND MDW CONFIDENCE...UPDATED 00Z...

* HIGH CONFIDENCE IN PCPN TRENDS.

* MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS.

* MEDIUM CONFIDENCE IN CIG/VIS TRENDS...BUT LOWER CONFIDENCE IN
EXACT TIMING OF IMPROVEMENT.

KREIN

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

THURSDAY...CHANCE OF FLURRIES IN THE AFTERNOON/EVENING. MVFR CIGS
POSSIBLE. WEST WINDS GUSTING TO 25-30KT.

FRIDAY...VFR EARLY. CHANCE OF SNOW WITH MVFR CIGS/VIS OVERNIGHT.

SATURDAY...CHANCE OF SNOW WITH MVFR CIGS/VIS EARLY...THE VFR
OVERNIGHT.

SUNDAY...VFR. WX NIL.

MONDAY...SLIGHT CHANCE RAIN/SNOW. MVFR CIGS/VIS POSSIBLE.

KREIN

.MARINE...
1248 PM CST

ALLSOPP

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLOOD WATCH...ILZ003-ILZ004-ILZ008-ILZ010-ILZ011-ILZ019 UNTIL 4
AM WEDNESDAY.

FLOOD WATCH...ILZ005-ILZ006-ILZ012-ILZ013-ILZ014-ILZ020-ILZ021-
ILZ022-ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 4 AM WEDNESDAY.

IN...FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 4 AM
WEDNESDAY.

LM...DENSE FOG ADVISORY...LMZ080-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-
LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878
UNTIL 10 PM TUESDAY.

GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...9 AM WEDNESDAY TO 6 AM
THURSDAY.

SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 4 AM WEDNESDAY.

AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

959 PM EST TUE JAN 29 2013

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

.SYNOPSIS...
ISSUED AT 337 PM EST TUE JAN 29 2013

NUMEROUS WEATHER HAZARDS WILL ACCOMPANY AN EXTREMELY POTENT SYSTEM
IMPACTING THE REGION THROUGH TOMORROW. VERY UNSEASONABLY WARM AND
MOIST CONDITIONS WILL BE IN PLACE THROUGH TONIGHT. AHEAD OF A
STRONG COLD FRONT SWEEPING THROUGH THE REGION...THE POTENTIAL WILL
EXIST FOR THUNDERSTORMS...HEAVY RAINFALL...FLOODING AND DAMAGING
WINDS. POTENTIAL FOR STRONG WINDS WILL CONTINUE BEHIND THE FRONTAL
BOUNDARY ON WEDNESDAY...AND FLOODING MAY LAST FOR SEVERAL DAYS OR
MORE.

.NEAR TERM /REST OF TONIGHT/...

ISSUED AT 942 PM EST TUE JAN 29 2013

UPDATE...
LINE OF STRONG TO SEVERE THUNDERSTORMS IS WELL OUT AHEAD OF THE
COLD FRONT AND CURRENTLY PUSHING EASTWARD THROUGH ILLINOIS AND
WESTERN KENTUCKY. TEMPS ACROSS CENTRAL INDIANA HAVE BEEN SLOWLY
RISING A FEW DEGREES OVER THE LAST FEW HOURS AS STRONG LOW LEVEL
JET ADVECTS WARM AIR AHEAD OF IT. SO...LOSS OF DIURNAL HEATING
HAS HAD LITTLE AFFECT ON ENVIRONMENT. INSTABILITY LOOKS MOST
FAVORABLE FOR SEVERE STORMS ACROSS THE SOUTHERN PORTIONS OF
FORECAST AREA PER LATEST LAPS ANALYSES.

PREVIOUS DISCUSSION... FOCUS OF THE NEAR TERM REMAINS ON SEVERE
WEATHER CHANCES AS WELL AS POSSIBLE HEAVY RAINFALL/FLOODING
POSSIBILITIES TONIGHT. THE PERIOD BEGINS WITH GOOD SHORT TERM
MODEL AGREEMENT AS TO THE LOCATION OF KEY FEATURES THAT MAY BRING
POSSIBLE SEVERE TO PORTIONS OF THE FORECAST AREA TONIGHT. AT
00Z/WED...THE LOW PRESSURE CENTER IS PROGGED TO BE OVER CENTRAL
MISSOURI...WITH ONGOING CONVECTION POSSIBLY ALREADY IN THE FORM OF
A SQUALL LINE ALONG A STRONG COLD FRONT STRETCHED FROM NORTHWEST
ILLINOIS...DOWN THROUGH CENTRAL MISSOURI...INTO EASTERN
OKLAHOMA/WESTERN ARKANSAS.

THERE DOES APPEAR TO BE SOME DIFFERENCES IN SPEED/TIMING OF THE
FRONT INTO THE FORECAST AREA...WITH THE HRRR AND RAP INTO THE AREA A
BIT QUICKER THE THE NAM AND GFS. PERSONAL EXPERIENCE HAS SHOWN THAT
THESE COLD FRONT/SQUALL LINE FEATURES TEND TO COME IN A BIT QUICKER
THAN SOMETIMES EXPECTED. THEREFORE...DECIDED TO TREND TOWARD THE
HRRR/RUC SOLNS.

AS WAS MENTIONED IN PREVIOUS DISCUSSIONS...DYNAMICS WILL NOT BE AN
ISSUE WITH THIS SYSTEM AS THE FRONT APPROACHES. A LOW LEVEL JET AOA
80 KTS AT 850 MB IS EXPECTED TO DEVELOP OUT AHEAD OF THE FRONT THIS
EVENING AND WILL TRANSLATE INTO OUR AREA TONIGHT. WITH 50 KT WINDS
LOCATED APPROXIMATELY 1000-1500 FEET ABOVE THE SURFACE
TONIGHT...DAMAGING WINDS MAY BECOME A REAL THREAT WITH ANY STORMS
THAT ARE ABLE TO REMAIN ORGANIZED AS THEY PUSH INTO THE FORECAST
AREA. ONE LIMITING FACTOR FOR CONVECTION REMAINING ORGANIZED INTO
THE OVERNIGHT HOURS IS INSTABILITY. SFC-BASED CAPE LOOKS TO BE IN
THE UNDER 200 J/KG RANGE...WHILE MUCAPE GIVES SLIGHTLY HIGHER
VALUES OF 200-400 J/KG AS THE FRONT MOVES INTO THE AREA. WITH THE
STRONG DYNAMICS AVAILABLE...WILL CONTINUE DAMAGING WINDS REFERENCE
IN THE GRIDS. ALSO KEEP IN MIND THAT WITH AMPLE LOW LEVEL
SHEAR...0-1 HELICITIES AOA 400-500 M2/S2...AN ISOLATED TORNADO
CANNOT BE RULED OUT.

THE BEST TIMING FOR SEVERE LOOKS TO START AT APPROXIMATELY 04-05Z
ACROSS WESTERN PORTIONS OF THE FORECAST AREA...TO ABOUT 10-11Z OVER
THE EAST. JUST ONE OTHER NOTE TO MENTION...THE HRRR ILLUSTRATES A
LINE OF CONVECTION DEVELOPING OUT AHEAD OF THE MAIN SQUALL LINE. TO
A LESSER EXTENT...THE RAP ALSO DEPICTS A SIMILAR SCENARIO. WHILE
THIS FORECAST HAS TAKEN THIS INTO CONSIDERATION...IT COULD STILL
ALLOW FOR AN EARLIER ONSET THAN FORECAST.

HEAVY RAINFALL IS ALSO IN PLAY TONIGHT AS MOISTURE HAS CONTINUED TO
STREAM NORTH INTO THE AREA. A PACIFIC TROPICAL PLUME OF MOISTURE HAS
BEEN EVIDENT ALL DAY ON WATER VAPOR IMAGERY STREAMING NORTHWEST INTO
LOWER MISSOURI/MID MISSISSIPPI/OHIO RIVER VALLEY STATES. COUPLE THAT
WITH 60 DEGREE DEWPOINTS CURRENTLY ON THE SOUTHWESTERN DOORSTEP OF
THE FORECAST AREA. PWATS TONIGHT AHEAD OF THE FRONT LOOK TO REACH
UPWARDS OF 1.40-1.50 INCHES...YIELDING A PERCENT OF NORMAL OF AROUND
300 PERCENT. WOULD NOT BE SURPRISED TO SEE A WIDESPREAD 1 TO 1.5
INCH RAINFALL...WITH SOME LOCALLY HIGHER AMOUNTS POSSIBLE.

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...

ISSUED AT 337 PM EST TUE JAN 29 2013

SHORT TERM PERIOD SEES A DIFFERENT SET OF CHALLENGES. ONE OF THE
INITIAL CHALLENGES WILL BE STRONG WINDS AFTER THE COLD FRONT SWEEPS
THROUGH THE AREA AND A DRY SLOT APPROACHES THE FORECAST AREA DURING
THE AFTERNOON HOURS. SUSTAINED WINDS AROUND 20-25 KTS...WITH THE
POSSIBILITY TO TAP 40 KT WINDS FROM APPROX 850 MB AS BOUNDARY LAYER
MIXES OUT. A WIND ADVISORY MAY BE NEED FOR A TIME IN THE LATE
MORNING TO EARLY EVENING HOURS ON WEDNESDAY.

ADDITIONALLY...SOME LIGHT SNOW SHOWERS MAY WRAP AROUND AND AFFECT
MAINLY NORTHERN PORTIONS OF THE FORECAST AREA WEDNESDAY NIGHT AS THE
UPPER TROUGH FINALLY PASSES THROUGH. NOT CURRENTLY EXPECTING MUCH IN
THE WAY OF ACCUMULATION.

ANOTHER UPPER TROUGH AND COLD FRONT PUSHES INTO THE THROUGH THE AREA
LATE THURSDAY INTO THURSDAY NIGHT...BRINGING AN ADDITIONAL CHANCE
FOR SNOW AND FALLING TEMPS.

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

ISSUED AT 144 PM EST TUE JAN 29 2013

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

THE EXTENDED PERIOD WILL NOT BE NEARLY AS ACTIVE AS THE FIRST FEW
DAYS OF THE FORECAST. FIRST OFF A SHORT WAVE TROUGH MOVING THROUGH
THE GREAT LAKES REGION MAY BRING A FEW SNOW SHOWERS TO CENTRAL
INDIANA AT THE BEGINNING OF THIS PERIOD. TEMPS/THICKNESS ALL LOOK
COLD ENOUGH FOR PLAIN SNOW DURING THIS TIME. ATTM ACCUMULATIONS
APPEAR TO BE AN INCH OR LESS. AFTER A COLD SHOT OF AIR THU AND
FRIDAY...TEMPERATURES WILL GRADUALLY MODERATE TO CLIMO OVER THE
WEEKEND AND INTO NEXT WEEK. SECOND HALF OF THE WEEKEND LOOKS DRY
AND INTO EARLY NEXT WEEK. ENSEMBLES SHOW SOME PRECIP BY NEXT
MONDAY/MONDAY NIGHT. TEMPERATURES LOOK WARM ENOUGH FOR A
SNOW/RAIN MIX ACROSS A GOOD PORTION OF THE AREA. HAVE SMALL
MINIMAL PRECIP CHANCES IN DURING THIS TIME.

.AVIATION /DISCUSSION FOR THE 30/03Z IND TAF UPDATE/...

ISSUED AT 920 PM EST TUE JAN 29 2013

PULLED THE SHOWERS AT IND BASED ON RADAR...OTHERWISE NO CHANGES.

PREVIOUS DISCUSSION FOLLOWS...

POTENT SPRING-LIKE WEATHER SYSTEM IS EXPECTED TO BRING STRONG TO
SEVERE THUNDERSTORMS TO CENTRAL INDIANA LATE THIS EVENING AND EARLY
OVERNIGHT. THE RAPID REFRESH REFLECTIVITY PROGS AND AWIPS-DISTANCE
SPEED TOOL SUGGEST A LINE OF STORMS SHOULD REACH HUF AND LAF AROUND
04Z AND IND AND BMG AROUND 06Z WITH PLENTY OF TRAILING RAIN. BASED
ON LIGHTNING DATA AND EXPECTED TIMING...WENT WITH IFR TEMPO
THUNDERSTORM GROUP AS THE ACTIVITY REACHES THE TERMINALS ALONG WITH
SOUTHWEST WINDS TO 30 KNOTS AND WIND GUSTS TO 40 KNOTS. HIGHER GUSTS
ARE POSSIBLE WITH THE AREA IN A SLIGHT RISK TONIGHT...SO MAY NEED TO
EVENTUALLY UP THOSE GUSTS TO SEVERE CRITERIA. FLIGHT CONDITIONS WILL
START AS MVFR AND COULD DROP TO IFR OVERNIGHT BEFORE COMING UP TO
VFR BY TOMORROW AFTERNOON BEHIND THE FRONTAL SYSTEM. WOULD NOT RULE
OUT A FEW RAIN SHOWERS TOMORROW AFTERNOON EVEN MIXING WITH
SNOW...BUT COVERAGE SHOULD BE ON THE LOW SIDE...SO LEFT THEM OUT FOR
NOW.

BASED ON VWP PROFILE DATA ALONG WITH BUFKIT...MOVED THE LOW LEVEL
WIND SHEAR UP A FEW HOURS. WINDS SHOULD STAY UP TOMORROW WITH GUSTS
TO 30 KNOTS OR MORE WITH DIRECTION SHIFTING TO WEST BEHIND THE
FRONTAL SYSTEM.

.IND WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH THROUGH WEDNESDAY MORNING FOR INZ021-028>031-035>049-
051>057-060>065-067>072.

SYNOPSIS...MRD
NEAR TERM...MRD/TDUD
SHORT TERM...MRD
LONG TERM....SMF
AVIATION...MK

AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

820 PM EST TUE JAN 29 2013

.UPDATE...

THE AVIATION SECTION HAS BEEN UPDATED BELOW.

.SYNOPSIS...
ISSUED AT 337 PM EST TUE JAN 29 2013

.NEAR TERM /TONIGHT/...

ISSUED AT 337 PM EST TUE JAN 29 2013

FOCUS OF THE NEAR TERM REMAINS ON SEVERE WEATHER CHANCES AS WELL AS
POSSIBLE HEAVY RAINFALL/FLOODING POSSIBILITIES TONIGHT. THE PERIOD
BEGINS WITH GOOD SHORT TERM MODEL AGREEMENT AS TO THE LOCATION OF
KEY FEATURES THAT MAY BRING POSSIBLE SEVERE TO PORTIONS OF THE
FORECAST AREA TONIGHT. AT 00Z/WED...THE LOW PRESSURE CENTER IS
PROGGED TO BE OVER CENTRAL MISSOURI...WITH ONGOING CONVECTION
POSSIBLY ALREADY IN THE FORM OF A SQUALL LINE ALONG A STRONG COLD
FRONT STRETCHED FROM NORTHWEST ILLINOIS...DOWN THROUGH CENTRAL
MISSOURI...INTO EASTERN OKLAHOMA/WESTERN ARKANSAS.

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...

ISSUED AT 337 PM EST TUE JAN 29 2013

ANOTHER UPPER TROUGH AND COLD FRONT PUSHES INTO THE THROUGH THE AREA
LATE THURSDAY INTO THURSDAY NIGHT...BRINGING AN ADDITIONAL CHANCE
FOR SNOW AND FALLING TEMPS.

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

ISSUED AT 144 PM EST TUE JAN 29 2013

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

.AVIATION /DISCUSSION FOR THE 30/03Z IND TAF UPDATE/...

ISSUED AT 920 PM EST TUE JAN 29 2013

PULLED THE SHOWERS AT IND BASED ON RADAR...OTHERWISE NO CHANGES.

PREVIOUS DISCUSSION FOLLOWS...

.IND WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH FROM 7 PM EST THIS EVENING THROUGH WEDNESDAY MORNING
FOR INZ021-028>031-035>049-051>057-060>065-067>072.

SYNOPSIS...MRD
NEAR TERM...MRD
SHORT TERM...MRD
LONG TERM....SMF
AVIATION...MK

AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

610 PM EST TUE JAN 29 2013

.UPDATE...

THE AVIATION SECTION HAS BEEN UPDATED BELOW.

.SYNOPSIS...
ISSUED AT 337 PM EST TUE JAN 29 2013

.NEAR TERM /TONIGHT/...

ISSUED AT 337 PM EST TUE JAN 29 2013

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...

ISSUED AT 337 PM EST TUE JAN 29 2013

ANOTHER UPPER TROUGH AND COLD FRONT PUSHES INTO THE THROUGH THE AREA
LATE THURSDAY INTO THURSDAY NIGHT...BRINGING AN ADDITIONAL CHANCE
FOR SNOW AND FALLING TEMPS.

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

ISSUED AT 144 PM EST TUE JAN 29 2013

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

.AVIATION /DISCUSSION FOR THE 30/00Z TAF ISSUANCE/...

ISSUED AT 610 PM EST TUE JAN 29 2013

.IND WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH FROM 7 PM EST THIS EVENING THROUGH WEDNESDAY MORNING
FOR INZ021-028>031-035>049-051>057-060>065-067>072.

SYNOPSIS...MRD
NEAR TERM...MRD
SHORT TERM...MRD
LONG TERM....SMF
AVIATION...MK

AREA FORECAST DISCUSSION

NWS DES MOINES IA

912 PM CST TUE JAN 29 2013

.UPDATE...
THERE WILL BE LITTLE CHANGE IN THINKING WITH A TOKEN EVENING UPDATE
TO FIT CURRENT OBS. WAS ORIGINALLY THINKING THAT FORECAST AMOUNTS
MAY BE TOO HIGH ON NW FRINGE OF FORECAST PRECIP SHIELD...HOWEVER 00Z
NAM IS NOW PLACING HEAVIEST SNOWFALL AXIS SW-NE RIGHT THROUGH DES
MOINES. FAR NW FRINGE OF ADVISORY MAY BE OVERDONE...BUT STILL LOOKS
LIKE FORT DODGE AND MASON CITY AREAS MAY BE BRUSHED...ESPECIALLY SRN
PORTIONS OF THOSE COUNTIES. NO CHANGES IN HEADLINES WHICH
CONFIDENCE IN ANY PARTICULAR SOLUTION NOT GREAT ENOUGH TO CHANGE
THINGS. LOOKED TO THE RAP FOR GUIDANCE BUT PAST SEVERAL RUNS ARE
LITTLE HELP AS THEY HAVE BEEN CONSISTENTLY TOO AGGRESSIVE IN TIMING
AND STRENGTH WITH PRECIP ONSET INTO IA.

00Z H85 ANALYSIS SHOWS STRONG WARM/MOIST ADVECTION INTO ST
JOESPH/KC METRO AREAS AND TOPS ARE COOLING THERE SO SEE LITTLE
REASON TO DOUBT PREVIOUS THINKING WITH PRECIP BLOSSOMING SHORTLY AND
THAT APPEARS TO BE THE CASE. RADAR ECHOES ARE STRENGTHENING AND
VIRGA DONUT SHRINKING. DUAL POL RADAR PRODUCTS SHOW RAIN/SNOW
LINE ROUGHLY ALONG BEDFORD-OSCEOLA-NEWTON LINE SO SHOULD SEE ONLY
SNOW TO N AND W OF THESE AREAS.

PREVIOUS 00Z UPDATE...ADJUSTED FORECAST AND HEADLINES TO NOT START
UNTIL 03Z BASED ON LATEST MODEL GUIDANCE AND OBSERVATIONAL TRENDS.
WILL OBVIOUSLY RE-EXAMINE FORECAST FURTHER AFTER 00Z MODELS COME IN
AND SYSTEM STARTS TO SHOW ITS HAND MORE UPSTREAM INTO NE AND KS.
ADDED 00Z TAF DISCUSSION.

.SHORT TERM /TONIGHT/...
UPPER WAVE EVIDENT ON WATER VAPOR DIGGING ALONG THE US/MEXICO BORDER
AND STARTING TO LIFT NORTHEASTWARD INTO THE TEX PANHANDLE...TO
CONTINUE ITS CURRENT TRAJECTORY NORTHEASTWARD THROUGH THE CENTRAL
PLAINS AND INTO THE MID MISSISSIPPI VALLEY BY EARLY WEDNESDAY. THE
STATE BECOMES SANDWICHED BETWEEN COUPLED JET STREAKS ALOFT...WITH
STRONGEST FRONTOGENETICAL LIFT SHOWING UP ACROSS THE SOUTHEASTERN
HALF OF THE CWA LATE THIS EVENING INTO THE OVERNIGHT HOURS. TROWAL
FEATURE TO ROTATE EASTWARD THROUGH CENTRAL/SOUTHEASTERN CWA...WITH
INCREASING MOISTURE IN THE LOW/MID LEVELS. DRIER AIR WORKING ITS WAY
INTO THE NORTH SHOULD YIELD A SHARP CUTOFF IN THE SNOW FIELD TO THE
NORTHWEST...WITH THE NORTHWESTERN CUTOFF TO THE HEAVIER SNOW FROM
NEAR CORNING NORTHEASTWARD TO WAVERLY. HEAVIEST AMOUNTS EXPECTED
ACROSS THE FAR SOUTHEASTERN CWA...WHERE QPF WILL BE GREATER AND
COULD SEE SOME WEAK INSTABILITY ALOFT ENHANCE SNOWFALL RATES AT
TIMES LATE TONIGHT. OVERALL THREE TO FOUR INCHES OF SNOW EXPECTED
TO FALL ACROSS THE SOUTHEASTERN HALF OF THE CWA BY 12Z WEDNESDAY.
SFC PRES GRADIENT TO TIGHTEN ON THE BACKSIDE OF THIS SYSTEM...WITH
STRONG CAA. 925MB TO 850MB WINDS EXPECTED TO BE IN THE 30 TO 35KT
RANGE BY LATE TONIGHT...WITH THESE WINDS TRANSLATING TO THE SURFACE
WITH THE STRONG CAA. THEREFORE EXPECTING SUSTAINED WINDS IN THE 20
TO 30 MPH RANGE...WITH GUSTS TO 35 MPH OR HIGHER BY LATE TONIGHT
ACROSS THE AREA. THIS WILL LEAD TO CONSIDERABLE BLOWING SNOW IN OPEN
AREAS. ADDITIONALLY WITH THE RESIDUAL SURFACE MOISTURE AROUND...AND
POSSIBILITY OF HEAVY WET SNOW INITIALLY BEFORE THE DRIER AIR WORKS
INTO THE AREA RESULTING IN A LIGHTER FLUFFIER SNOW...SOME ICING MAY
OCCUR ON ROADWAYS...TREES BRANCHES...AND POWER LINES. THEREFORE WILL
CONTINUE THE WINTER HEADLINES AS THEY ARE FOR TONIGHT INTO WEDNESDAY
MORNING.

.LONG TERM /WEDNESDAY THROUGH TUESDAY/...
RAPIDLY DEEPENING LOW PRESSURE WILL BE OVER CENTRAL ILLINOIS BY 12Z
AND WILL SHIFT NORTHEAST INTO LOWER MICHIGAN BY 18Z. PV ANOMALY
CURRENTLY OVER WEST CENTRAL TEXAS WILL BE ENTERING SOUTHEAST IOWA AS
WELL BY 12Z WITH STRONG QG FORCING CONTINUING THROUGH MID TO LATE
MORNING OVER THE SOUTHEAST. A PORTION OF THE WARM CONVEYOR WILL
CONTINUE TO SUPPLY MOISTURE INTO THE SOUTHEAST EARLY IN THE PERIOD
BEFORE DRIER AIR ADVECTS IN BY MID TO LATE MORNING. BEST SNOW
ACCUMULATIONS WILL OCCUR THROUGH 15Z THEN DIMINISHING AFTER THAT
TIME. THE MOST DIFFICULT PORTION OF THE SNOW FORECAST REMAINS THE
NORTHWEST EDGE. ANY SHIFT SOUTHEAST OF THE STORM TRACK WOULD REDUCE
SNOWFALL AMOUNT IN THESE REGIONS.

THE STRONG WIND POTENTIAL WITH THIS SYSTEM WEDNESDAY MORNING REMAINS
HIGH. IN ADDITION TO A TIGHT PRESSURE GRADIENT OF 30 TO 40
UBARS/KM...THE STRONG COLD ADVECTION WILL KEEP WINDS MIXED UP TO 900
MB WITH 35 TO 40 KTS AVAILABLE IN THAT MIXED LAYER. THE COLD
ADVECTION WILL LEAD TO GOOD MOMENTUM TRANSFER OF THE WINDS WITH
STRONGEST WINDS OCCURRING 12-18Z. AREAS WITH 2-3 INCHES OF SNOW OR
MORE WILL HAVE SIGNIFICANT BLOWING SNOW WEDNESDAY MORNING THAT COULD
APPROACH BLIZZARD CRITERIA. IN ADDITION...WITH WARMER NEAR SFC
TEMPERATURES...THE SNOW FALL COULD HAVE SIMILAR PROPERTIES TO THAT
OF THE DECEMBER BLIZZARD INITIALLY IN THAT IT WILL MELT THEN FREEZE
UNDER THE FALLING SNOW RESULTING IN AN ICY SUB LAYER. THIS WOULD
MAKE TRAVEL EXTREMELY HAZARDOUS THROUGH THIS EVENT.

THE ACCUMULATING SNOW WILL END BY NOON WITH STEADY OR FALLING
TEMPERATURES THE REMAINDER OF THE DAY. TEMPERATURES WILL BE COLD
WEDNESDAY NIGHT WITH LOWS BELOW ZERO NORTH THOUGH LINGERING CLOUDS
COULD HOLD TEMPERATURES UP OVERALL. ANOTHER UPPER WAVE WILL PUSH
THROUGH WEDNESDAY NIGHT AND THURSDAY MORNING WITH AN ARCTIC BOUNDARY
MOVING THROUGH THURSDAY AS WELL. WIND CHILL VALUES BY WEDNESDAY
NIGHT AND THURSDAY WILL APPROACH 25 BELOW OVER NORTHERN IOWA DURING
THIS PERIOD. CURRENTLY HAVE FLURRIES IN THE FORECAST FOR THURSDAY
BUT THIS WILL NEED TO BE REEVALUATED FOR POTENTIAL OF VERY LIGHT
SNOWFALL WITH A BRIEF PERIOD OF SATURATION AND LIFT THROUGH THE
DENDRITIC LAYER. ARCTIC HIGH PRESSURE WILL DROP SOUTHEAST INTO THE
STATE THURSDAY NIGHT. OVERNIGHT LOW TEMPERATURE WELL BELOW ZERO ARE
EXPECTED. POSSIBLE TO BE WELL BELOW GUIDANCE WHERE THE NEW SNOW PACK
IS.

ANOTHER UPPER LEVEL SYSTEM WILL FOLLOW THE HIGH PRESSURE DEPARTURE
BY FRIDAY AFTERNOON. ANOTHER PERIOD OF VERY LIGHT SNOW MAY OCCUR
WITH THE SYSTEM PASSAGE. GRADUAL WARMING INTO THE WEEKEND WITH
TEMPERATURES PUSHING INTO THE 20S AND 30S. THE NEXT UPPER WAVE
DROPPING THROUGH NORTHWEST FLOW WILL ARRIVE MONDAY AND WILL DROP
ANOTHER PUSH OF COLD AIR INTO THE STATE. THE COLD AIR WILL BE SHORT
LIVED WITH RIDGING BUILDING INTO FROM THE WEST BY TUESDAY.

.AVIATION...30/00Z
MVFR/IFR CIGS IN PLACE ACROSS MUCH OF FORECAST AREA AND CONDITIONS
ARE EXPECTED TO WORSEN LATER TONIGHT AS UPSTREAM KS/NE PRECIP
EXPANDS AS IT REACHES IA OVERNIGHT. CONDITIONS SHOULD DETERIORATE
TO IFR/LIFR BY MIDNIGHT OVER SE HALF OF STATE MAINLY AFFECTING
KALO/KDSM/KOTM TAF SITES. NW WINDS WILL CONTINUE TO INCREASE...AND
WITH MOD/HEAVY SNOW DEVELOPING BY EARLY WED MORNING...EXPECT
SIGNIFICANT REDUCTIONS IN VSBY DUE TO SNOW AND BLOWING SNOW BY THAT
TIME. NW WINDS WILL REMAIN STRONG INTO WED WITH SOME GUSTS OVER
30KTS...BUT VSBYS SHOULD IMPROVE LATER IN THE DAY.

.DMX WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING FROM 9 PM THIS EVENING TO NOON CST WED
ADAIR-ADAMS-BLACK HAWK-BOONE-BREMER-BUTLER-CLARKE-DALLAS-DECATUR-
GRUNDY-HARDIN-JASPER-MADISON-MARSHALL-POLK-RINGGOLD-STORY-TAMA-
TAYLOR-UNION-WARREN-APPANOOSE-DAVIS-LUCAS-MAHASKA-MARION-MONROE-
POWESHIEK-WAPELLO-WAYNE

WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON CST WED
AUDUBON-CARROLL-CASS-CERRO GORDO-FRANKLIN-GREENE-GUTHRIE-HAMILTON-
WEBSTER-WRIGHT

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

AREA FORECAST DISCUSSION

NWS DES MOINES IA

120 AM CST MON JAN 28 2013

...UPDATED AVIATION DISCUSSION...

.UPDATE...
DENSE FOG HAS DEVELOPED ACROSS MUCH OF THE CWA...ESPECIALLY AREAS
WHICH RECEIVED PRECIPITATION SUNDAY. WHILE AREAS ACROSS THE SOUTH
NEAR BOUNDARY AREA NOT EXPERIENCING WIDESPREAD DENSE FOG...EXPECT
FOG TO DEVELOP OVERNIGHT AS MOISTURE INCREASES AND WINDS DECREASE.
HAVE EXPANDED DENSE FOG ADVISORY TO INCLUDE ENTIRE CWA THROUGH 15Z
MONDAY MORNING. AREAS OF DENSE FOG IN SOME COUNTIES MAY BE PATCHY.
IN ADDITION...ACROSS THE NORTH WITH TEMPERATURES NEAR OR BELOW
FREEZING...COULD SEE REFREEZING OF ROADWAYS OR FOG DEPOSITS ON
ROADWAYS CREATING DANGEROUS TRAVEL CONDITIONS.

.SHORT TERM /TONIGHT/...
UPPER LEVEL FORCING CONTINUES TO WANE WITH DEPARTING KINEMATIC AND
THERMODYNAMIC FORCING AS SHORT WAVE CROSSES SRN MN/WI BORDER.
POCKET OF WEAK INSTABILITY WITH A FEW HUNDRED MUCAPES IS ALSO
EXITING INTO IL. THIS HAD ENDED OUR THREAT OF SHOWERS AND
SUBSTANTIAL PRECIP. HOWEVER WEAK FORCING AND CERTAINLY MOISTURE
LINGERS 2KM AND BELOW AND WILL RESULT IN PERSISTENT DRIZZLE OR
FREEZING DRIZZLE. THIS SENSIBLE WEATHER IS DEPICTED NICELY BY THE
LOW LEVEL RAP 285-295K ISENT LAYER WHICH SHOWS MODERATE MOISTURE
TRANSPORT AND LIFT THROUGH THE EVENING. THIS WILL ALSO KEEP LOW
CLOUDS AND FOG LOCKED IN PLACE. FOG MAY BE DENSE AT TIMES...BUT
CONFIDENCE IN WIDESPREAD 1/4SM OR LESS VSBYS IS NOT GREAT ENOUGH TO
HEADLINE QUITE YET WITH MOISTURE TRANSPORT ENDING LATE AND LITTLE
RADIATIONAL COOLING. ALTHOUGH ONLY TOKEN ADDITIONAL ICE
ACCUMULATIONS ARE ANTICIPATED...HAVE LEFT HEADLINES UNCHANGED
NORTH. LITTLE IMPROVEMENT IS ANTICIPATED THERE WITH TEMPS HOVERING
AROUND 32F ALONG WITH THE DRIZZLE AND FOG. ADVISORY CANCELED
FARTHER SOUTH WHERE TEMPS SHOULD REMAIN ABOVE FREEZING.

.LONG TERM /MONDAY THROUGH SUNDAY/...
FAIRLY ACTIVE MID/LONG RANGE ACROSS THE AREA WITH MAJOR FOCUS ON
MONDAY INTO TUESDAY. LARGE UPPER LEVEL TROUGH THAT HAS BEEN SLOWLY
PROGRESSING THROUGH THE INTERMOUNTAIN WEST...WILL CONTINUE TO
TRANSLATE EASTWARD ACROSS THE CENTRAL PLAINS INTO THE OHIO VALLEY
THROUGH WEDNESDAY. INITIALLY THE STATE WILL REMAIN IN SOUTHWEST FLOW
ALOFT...WITH CONTINUE LOW LEVEL MOISTURE PUMPING NORTHWARD FROM THE
GULF OF MEXICO. SFC LOW PRESSURE DEVELOPING IN LEE OF THE
ROCKIES...BEGINS TO SHIFT EAST AND ELONGATE INTO CENTRAL KS/SC
NEBRASKA TOWARD MONDAY AFTERNOON. AN ASSOCIATED WARM FRONT WILL LIFT
NORTHWARD THROUGH THE STATE LATE MONDAY INTO MONDAY NIGHT. MOISTURE
OVERRUNNING THE AREA TO THE NORTH OF THIS WARM FRONT WILL LEAD TO
LOW STRATUS AND FOG LINGERING ACROSS THE CWA MONDAY. ISENTROPIC LIFT
EVIDENT ON THE 285K TO 290K SURFACES BEGINS TO SHOW UP ACROSS THE
SOUTHERN CWA BY LATE MONDAY MORNING WITH LIFT SPREADING NORTHWARD
INTO THE AFTERNOON HOURS. THIS WILL BRING THE CHANCE FOR DRIZZLE OR
LIGHT RAIN TO MUCH OF THE SOUTHERN HALF OF IOWA BY MONDAY AFTERNOON
IN ADDITION TO THE LOW CLOUDS/FOG. VISIBILITIES EXPECTED TO BE QUITE
LOW WITH THE FOG THROUGHOUT THE MORNING HOURS...WITH SOME
IMPROVEMENT IN THE AFTERNOON. POSSIBILITY OF NEEDING A DENSE FOG
ADVISORY FOR THE MORNING HOURS...BUT WILL NOT ISSUE NOW DUE TO
WINTER HEADLINES ALREADY IN EFFECT FOR SIMPLICITY. GREATER PUSH OF
MOISTURE...WITH DEEPER SATURATION EXPECTED AND CONTINUE WAA INTO
MONDAY NIGHT AS WARM FRONT LIFTS NORTHWARD THROUGH THE STATE. HAVE A
NON-DIURNAL TEMPERATURE TREND MONDAY NIGHT AS AREAS EXPECTED TO WARM
OR REMAIN STEADY BEHIND THE WARM FRONT. FOG COULD CONTINUE TO BE AN
ISSUE INTO MONDAY NIGHT WITH ABUNDANT LOW LEVEL MOISTURE.
ADDITIONALLY NAM/GFS BOTH ADVERTISE SOME ELEVATED INSTABILITY
SPREADING NORTHWARD INTO THE CWA...WITH THE NAM MOST AGGRESSIVE.
THEREFORE CONTINUED THE THUNDER MENTION ACROSS THE SOUTHERN
HALF/EASTERN HALF OF THE CWA.

AS THE SFC LOW LIFTS NORTHEASTWARD THROUGH THE STATE INTO TUESDAY
MORNING...ASSOCIATED COLD FRONT TO PUSH THROUGH CWA TUESDAY. THIS
WILL LEAD TO PRECIPITATION TRANSITIONING TO A MIX OF RAIN/SNOW TO
ALL SNOW/FLURRIES ACROSS THE NORTHERN CWA BEFORE PRECIPITATION
TAPERS OFF LATER THAT DAY. POSSIBILITY STILL EXISTS THAT COULD SEE A
MIX OF FREEZING RAIN AS WELL...AS DEPENDS ON HOW DEEP SATURATION IS
AND IF ICE CAN BE INTRODUCED INTO THE COLUMN. CURRENT NAM SOUNDINGS
SUGGEST DEEP ENOUGH SATURATION WITH ICE INTRODUCED WHICH WOULD ALLOW
FOR SNOW...WHILE GFS SUGGEST DRIER AIR ALOFT WITH NO ICE
INTRODUCTION LEADING TO RAIN/FZRA/FZDZ DEPENDING ON SURFACE TEMPS.
FOR NOW HAVE TRENDED FORECAST TOWARD THE NAM SOLUTION. BROAD UPPER
LEVEL TROUGH THEN REMAINS ACROSS THE EASTERN US...WITH NORTHWESTERLY
FLOW ALOFT FOR THE REMAINDER OF THE PERIOD. THIS WILL ALLOW FOR A
SERIES OF WEAK SHORTWAVES TO TRAVEL THROUGH THE MAIN UPPER LEVEL
TROUGH AND DROP SOUTH THROUGH THE CWA. THIS WILL BRING CONTINUED
PUSHES OF ARCTIC AIR FOR LATE THIS WEEK INTO THE WEEKEND...WITH H85
TEMPS DROPPING INTO THE NEGATIVE TEENS TO 20S CELSIUS. THIS WILL
SEND TEMPERATURES TO BELOW AVERAGE BY THE END OF THE WEEK INTO THE
WEEKEND. WITH EACH WAVE PASSAGE...SOME FLURRIES OR LIGHT SNOW MAY BE
POSSIBLE BUT HAVE LEFT THE FORECAST MAINLY DRY FOR NOW WITH THE
UNCERTAINTY IN THE TIMING OF EACH IMPULSE. BROAD UPPER LEVEL RIDGING
BEGINS TO NUDGE INTO THE CENTRAL US TOWARD THE END OF THE WEEKEND
INTO EARLY NEXT WEEK...SUGGESTING A WARMING TREND AS H85 TEMPS CLIMB
BACK ABOVE FREEZING.

.AVIATION...28/06Z
NO MAJOR CHANGES FROM PREVIOUS FORECAST AS CONFIDENCE IS HIGH WITH
LIFR/IFR CONDITIONS THROUGH THE CRITICAL TAF PERIOD AND INTO MONDAY
MORNING. CIGS LOOK TO REMAIN BELOW 500 FEET AND VIS WILL BOUNCE
AROUND BELOW 1SM. CURRENT DRIZZLE WILL COME TO AN END BY AROUND 08Z
AT ALO/OTM...AND A BIT SOONER AT DSM. CIGS/VIS MAY IMPROVE TO MVFR
LATE MONDAY MORNING INTO THE AFTERNOON HOURS...BUT ANTICIPATED TO
REDEVELOP MONDAY NIGHT. HAVE INTRODUCED IFR/LIFR CONDITIONS PAST 00Z
TUESDAY.

.DMX WATCHES/WARNINGS/ADVISORIES...

DENSE FOG ADVISORY IN EFFECT UNTIL 9 AM CST MONDAY MORNING FOR ALL
OF CENTRAL IOWA.

SHORT TERM...SMALL
LONG TERM...BEERENDS
AVIATION...PODRAZIK
UPDATE...AWB

AREA FORECAST DISCUSSION

NWS DES MOINES IA

1155 PM CST SUN JAN 27 2013

...UPDATED AVIATION DISCUSSION...

.DMX WATCHES/WARNINGS/ADVISORIES...

DENSE FOG ADVISORY IN EFFECT UNTIL 9 AM CST MONDAY MORNING FOR ALL
OF CENTRAL IOWA EXCEPT FOR PORTIONS OF NORTH CENTRAL IOWA.

SHORT TERM...SMALL
LONG TERM...BEERENDS
AVIATION...PODRAZIK

AREA FORECAST DISCUSSION

NWS TOPEKA KS

556 PM CST TUE JAN 29 2013

.DISCUSSION...
21Z RAP AND 18Z NAM HAVE STARTED TO SHOW SOME INDICATION OF A DECENT
FRONTOGENETICAL BAND DEVELOPING MAINLY DURING THE 06Z TO 12Z TIME
FRAME. WITH RECENT RADAR TRENDS SHOWING A BAND STARTING TO FORM
ACROSS WESTERN KS...AM BEGINNING TO THINK THAT MODELS ARE DOING A
REASONABLE JOB DEPICTING THE SYSTEM AS IT LIFTS OUT OVERNIGHT.
CONFIDENCE IS INCREASING THAT THERE WILL BE SNOW. SNOW AMOUNTS SEEM
TO BE IN THE BALLPARK INITIALLY. WITH SOME UNCERTAINTY FROM THE PREV
FORECAST ABOUT MESOSCALE FORCING...THINK THAT FORECAST SNOW AMOUNTS
ARE PROBABLY NOT ON THE LOW SIDE. THERE ARE STILL SOME QUESTIONS
WITH SOME INDICATIONS OF MID LEVEL DRY AIR COMING IN AT THE
DENDRITIC GROWTH ZONE AND A GENERAL LACK OF INSTABILITY OF
CONDITIONAL INSTABILITY THAT COULD ACT TO KEEP SNOW AMOUNT ON WITHIN
THE FORECASTED VALUES. IF ANYTHING WILL NEED TO WATCH THINGS
PROGRESS AND POTENTIALLY EXPAND THE ADVISORY IF INDEED A BAND OF
MODERATE SNOW MOVES ACROSS THE AREA. MODELS CONTINUE TO SHOW A
STRENGTHENING PRESSURE GRADIENT WITH NORTH AND NORTHWEST WINDS
GUSTING UP TO 35 MPH.

WOLTERS

.AVIATION...
WITH INCREASING CONFIDENCE IN SNOW MOVING IN FROM THE WEST...THERE
IS INCREASED CONFIDENCE IN IFR AND LIFR CONDITIONS FORMING
OVERNIGHT. AT THIS TIME...THE BEST GUESS FOR WHEN THE HEAVIER SNOW
WILL OCCUR IS BETWEEN 04Z AND 11Z AT THE TERMINALS. BY 15Z THE
FORCING LOOKS TO MOVE TO THE EAST OF THE AREA WITH CONDITIONS
IMPROVING.

WOLTERS

.PREV DISCUSSION... /328 PM CST TUE JAN 29 2013/
THE ABRUPT RETURN TO WINTER CONTINUES TODAY ACROSS THE FORECAST
AREA...AFTER A ROUND OF MORNING SHOWERS AND THUNDERSTORMS FOR
EASTERN PORTIONS OF THE STATE. THE DEEP LONGWAVE TROF CONTINUES TO
MOVE EASTWARD ACROSS THE ROCKY MOUNTAINS AND INTO THE HIGH PLAINS.
ENERGY ROTATING THROUGH THE TX PANHANDLES AIDING IN ENHANCING A
NEGATIVE TILT TO THE SOUTHERN STREAM AS IT LIFTS INTO OUR AREA
THIS EVENING AND OVERNIGHT.

HAVE EXPANDED THE WINTER WEATHER ADVISORY BOTH WEST AND SOUTH A
FEW COUNTIES. STILL APPEARS AS IF FAR NE COUNTIES WILL GET THE
HIGHER SNOW AMOUNTS WHERE BAND OF FRONTOGENESIS TRACKS WEST TO
EAST GENERALLY NORTH OF THE INTERSTATE...AS DOES THE MID LEVEL
DEFORMATION ZONE. HARD TO SEE A TIME WHEN ALL INGREDIENTS COME
TOGETHER FOR A BANDED HEAVY SNOW EVENT...ALTHOUGH AROUND 06Z
NORTH OF THE MHK AREA DO SEE SOME FRONTOGENETIC FORCING ALIGNED
WITH SOME NEGATIVE EPV...THEREFORE INCREASED SNOW TOTALS FOR THIS
AREA. 2-3 INCH LINE RUNS GENERALLY ALONG THE INTERSTATE WITH
DIMINISHING AMOUNTS SOUTH AND HIGHER NUMBERS NORTH AND EAST.
STARTED ADVISORY WEST AT 6PM FOLLOWED BY AN 11PM START FOR
COUNTIES FARTHER EAST. OF CONCERN ARE THE WINDS THAT ACCOMPANY THIS
SYSTEM AS THE SNOW FALLS OVERNIGHT AND INTO THE EARLY COMMUTE
TOMORROW MORNING. SNOW WILL REDUCE VISIBILITIES AND MAY MAKE ROADS
DIFFICULT TO KEEP CLEAR...SO THAT EVEN A FEW INCHES OF SNOW MAY
BRING TRAVEL PROBLEMS. SNOW SHOULD END BY 9AM AND WILL LIKELY END
A FEW HOURS SOONER OUT WEST AND CAN ADJUST ADVISORY ENDING AS
NEEDED.

THURSDAY THROUGH NEXT TUESDAY...DRY WEATHER WILL LIKELY CONTINUE
THROUGH THE REMAINDER OF THE FORECAST PERIOD AS COLD AND DRY AIR
PLUNGES SOUTHWARD INTO THE CENTRAL PLAINS. NORTHWEST FLOW ALOFT ON
THE EASTERN EDGE OF A STRONGLY AMPLIFIED RIDGE OVER THE WESTERN
CONUS WILL PREVENT THE FORMATION OF ANY STRONG SURFACE TROUGH AND
SUBSEQUENT WARM AIR ADVECTION THROUGH THE REST OF THE WORK WEEK. THE
FIRST PUSH OF COLD AIR WILL ALSO LIKELY BE REINFORCED BY A SECOND
PUSH OF COLD AIR ON THURSDAY NIGHT...WHICH MODELS CURRENTLY PROG TO
BE CHARACTERIZED BY 850 MB TEMPERATURES AROUND -15 DEGREES C. THE
COLDEST MORNING AT THIS TIME LOOKS TO BE FRIDAY MORNING...WHEN THE
SURFACE HIGH ASSOCIATED WITH THE ARCTIC AIRMASS BECOMES CENTERED
OVER NORTHEAST KANSAS. CURRENTLY THE FORECAST FOR FRIDAY MORNING
REFLECTS SLIGHTLY LOWER TEMPS THAN THE PREVIOUS FORECAST SUGGESTED
DUE TO THE FACT THAT SNOW FROM TUESDAY NIGHT/WED MORNING WILL LIKELY
LINGER PREVENTING THE POLAR AIR FROM MODIFYING MUCH. GIVEN THAT SNOW
WILL LIKELY STILL BE ON THE GROUND AND THAT SKIES WILL CLEAR AND
WINDS WILL BE CALM...IN RESPONSE TO THE SURFACE HIGH...EXPECT FRIDAY
MORNING TO BE VERY CHILLY...WITH LOWS IN THE SINGLE DIGITS TO LOWER
TEENS.

BY SATURDAY THE SURFACE HIGH WILL SLIDE EASTWARD AND SOUTHERLY
RETURN FLOW WILL COMMENCE ON THE BACKSIDE OF THE HIGH. CONCURRENTLY
THE AFOREMENTIONED WESTERN CONUS RIDGE MAY SHIFT EVER SO SLIGHTLY TO
THE EAST...ALLOWING THE COLD AIR ASSOCIATED WITH THE BROAD HUDSON
BAY LOW TO ALSO SHIFT EAST. THE BOTTOM LINE FOR THE WEEKEND AND INTO
NEXT WEEK IS A GRADUAL WARMING TREND AS SURFACE WINDS WILL BE
WESTERLY TO SOUTHWESTERLY...WHICH WILL INTRODUCE A SLIGHT DOWNSLOPE
COMPONENT...AIDING IN SURFACE TEMP WARMING. AT THIS POINT MAX TEMPS
LOOK TO RUN ABOUT 10 DEGREES ABOVE NORMAL FROM SUNDAY THROUGH
NEXT TUESDAY...BUT THIS COULD CHANGE A FEW DEGREES EITHER WAY
DEPENDING ON HOW FAST THE SNOW MELTS.

.TOP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 11 PM THIS EVENING TO 9 AM CST
WEDNESDAY FOR KSZ010>012-023-024-026-039-040.

WINTER WEATHER ADVISORY UNTIL 9 AM CST WEDNESDAY FOR KSZ008-009-
020>022.

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

520 PM CST TUE JAN 29 2013

...UPDATED AVIATION DISCUSSION...

.SYNOPSIS...
ISSUED AT 1131 AM CST TUE JAN 29 2013

A VERY SHARP UPPER TROUGH EXTENDED FROM THE EASTERN MONTANA PLAINS
THROUGH THE SOUTHERN ROCKIES THIS MORNING. ON THE EAST SIDE OF THE
TROUGH AS AN INTENSE 120KT JET EXTENDING FROM WESTERN MEXICO THROUGH
WEST TEXAS AND THE CENTRAL HIGH PLAINS REGION (INCLUDING WESTERN
KANSAS). A COLD FRONT AT 850 MB HAD EXTENDED AS FAR SOUTHEAST AS
DODGE CITY, AS WAS MARKED BY A TIGHT TEMPERATURE GRADIENT ACROSS
SOUTH CENTRAL KANSAS. DEFORMATION ZONE SNOW HAD DEVELOPED ACROSS THE
HIGH PLAINS OF COLORADO AND NORTHWEST KANSAS, AS WAS EVIDENT ON
REGIONAL RADAR COMPOSITES. METAR OBSERVATIONS AT LHX/LIC/ITR/GLD ALL
INDICATED PERSISTENT LIGHT SNOW INTENSITIES.

.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 245 PM CST TUE JAN 29 2013

THE IMMEDIATE CONCERN WILL BE NOW-CASTING A SNOW EPISODE ACROSS WEST
CENTRAL KANSAS AND DETERMINING THE EASTERN EXTENT OF IMPACT. THE
SNOW THAT WAS RAPIDLY EXPANDING ACROSS WEST CENTRAL KANSAS IN THE
AFTERNOON WAS DISTRIBUTING WEAKLY BANDED CHARACTERISTICS ON RADAR,
BUT NOTHING THAT WOULD INDICATE VERY INTENSE SNOW RATES FROM
STRONGLY BANDED ZONES. THE LATEST RAPID REFRESH TRENDS ARE NOT
AS OPTIMISTIC FOR ACCUMULATING SNOW ACROSS OUR EXTREME SOUTHWEST
COUNTIES THAT ARE IN THE WINTER WEATHER ADVISORY, BUT APPEARS TO
EXPANDS THE BEST ACCUMULATING SNOWFALL AMOUNTS TO AROUND 2 INCHES FROM
GARDEN CITY AND SCOTT CITY , NORTHWARD THROUGH WAKEENEY AND NORTH
CENTRAL KANSAS THROUGH LATE EVENING. THIS IS FAIRLY WELL
COINCIDENT WITH THE CURRENT WINTER HEADLINE THROUGH THAT REGION
AND TIME FRAME.

IT IS UNCERTAIN JUST HOW LONG LIGHT SNOW WILL PERSIST ACROSS
PORTIONS OF CENTRAL KANSAS THOUGH TONIGHT AND INTO THE OVERNIGHT.
HOWEVER, BASED ON THE MODEL RELATIVE HUMIDITY FIELDS, IT IS SAFE TO
SAY THAT LOW LEVEL STRATUS WILL LIKELY BE SLOW TO CLEAR FROM WEST TO
EAST. THIS WILL BE DUE TO THE COLD AIR UNDER THE UPPER TROUGH
ROTATING INTO THE UPPER MIDWEST BY LATE DAY WEDNESDAY. THE DEEP
NORTHWEST FLOW WILL AID IN INCREASING SUBSIDENCE THROUGH EARLY
WEDNESDAY MORNING. SCATTERED TO BROKEN MID LEVEL CLOUDS ARE STILL
LIKELY BY EARLY WEDNESDAY AFTERNOON. THERE IS A LOT OF MODEL
CONSENSUS FOR COLDER TEMPERATURES FALLING INTO THE TEENS IN THE
WESTERN COUNTIES, WHERE DRIER AIR WILL LIKELY BE LOCATED, NOT TO
MENTION POTENTIAL FOR SOME FRESH SNOW ON THE GROUND. CENTRAL
KANSAS IS GENERALLY MODELED AS WARMER WITH LOWS ONLY IN THE LOW
20S.

AS A RESULT OF THE PATTERN, WEDNESDAY WILL REMAIN LARGELY COLD AND
BREEZY. BETTER CHANCES FOR INSOLATION WILL BE FOUND ACROSS THE
WESTERN COUNTIES IN THE AFTERNOON. BY CONTRAST. COLD AIR SHOULD BE
ENTRENCHED ACROSS CENTRAL NEBRASKA INTO CENTRAL KANSAS. THE
GENERAL CONSENSUS IS FOR HIGHS TO ONLY REACH THE LOW TO MID 30`S
ACROSS CENTRAL KANSAS, AND TO AROUND 40 DEGREES IN THE WEST. THE
SURFACE PRESSURE GRADIENT WILL ALSO SLACKEN DURING THE DAY. AS A
RESULT BREEZY NORTHWEST WINDS IN THE MORNING WILL BECOME LIGHT
WESTERLY WITH TIME THROUGH THE DAY.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 328 PM CST TUE JAN 29 2013

WEDNESDAY NIGHT THROUGH FRIDAY:
DURING THIS PERIOD...A LONGWAVE TROUGH AXIS OVER THE CENTRAL PORTION
OF NORTH AMERICA WILL GRADUALLY SHIFT EAST AS AN UPPER LEVEL RIDGE
BUILDS EASTWARD ACROSS WESTERN NORTH AMERICA. THE BEGINNING OF THIS
TIME PERIOD WILL BE FAIRLY CHALLENGING FROM A TEMPERATURE FORECAST
STANDPOINT AS A BRUTALLY COLD ARCTIC AIRMASS PUSHES SOUTH INTO THE
NORTHERN GREAT PLAINS. THIS WILL LEAD TO A RATHER UNCERTAIN
TEMPERATURE FORECAST FOR THE DAY THURSDAY AS THE LEADING EDGE OF THE
ARCTIC AIRMASS WILL BE IMPINGING ON NORTHERN/CENTRAL KANSAS BY
MIDDAY. BOTH THE GFS AND ECMWF MODELS ARE IN FAIRLY GOOD AGREEMENT
OF THE ARCTIC FRONT EXTENDING FROM FAR NORTHEAST COLORADO INTO
CENTRAL KANSAS BY 18Z THURSDAY. BEFORE THE FRONT MOVES
IN...TEMPERATURES SHOULD WARM INTO THE UPPER 30S/LOWER 40S NORTHEAST
OF A DIGHTON TO LACROSSE LINE...BUT BY EARLY/MID AFTERNOON
TEMPERATURES WILL LIKELY BEGIN TO FALL BACK DOWN INTO THE LOWER 30S
OR EVEN UPPER 20S (ESPECIALLY IN ELLIS COUNTY). MEANWHILE SOUTH OF
THE FRONT THURSDAY...HIGHS SHOULD REACH THE LOWER TO MID 50S...WITH
THE MOST LIKELY LOCATION SEEING THESE TEMPERATURES SOUTH AND WEST OF
A JOHNSON TO MEADE LINE. WE WILL ONLY SEE A GLANCING BLOW FROM THIS
CANADIAN AIRMASS AS THE CENTER OF THE ARCTIC HIGH MOVES TO THE
KANSAS-MISSOURI BORDER BY 12Z FRIDAY. LOW TEMPERATURES WILL BE IN
THE TEENS ACROSS CENTRAL KANSAS TO THE LOWER/MID 20S
ELSEWHERE...WITH A WIND SHIFT BACK TO THE SOUTHEAST BY DAYBREAK
FRIDAY. FRIDAY WILL ALSO BE A CHALLENGING TEMPERATURE FORECAST AS
THE SURFACE WIND FLOW WILL BE RECIRCULATING MODIFIED COLD AIR AROUND
THE WESTERN PERIPHERY OF THE COLD HIGH. THE CHALLENGE LIES IN THE
FACT THAT AT THE SAME TIME...ANOTHER SHORTWAVE TROUGH WILL BE
APPROACHING THE HIGH PLAINS IN THE NORTHWEST FLOW PATTERN WHICH WILL
LEAD TO DOWNSLOPE WESTERLY MOMENTUM IN THE LOWER TROPOSPHERE. AT
SOME POINT DURING THE DAY FRIDAY...THIS WESTERLY MOMENTUM WILL MIX
DOWN TO THE SURFACE AND A FAIRLY IMPRESSIVE WARM-UP MAY RESULT.
HAVE KEPT HIGH TEMPERATURE FORECAST IN THE MID TO UPPER 40S
GENERALLY EAST OF HIGHWAY 283...WITH LOWER TO MID 50S EXPECTED
ACROSS FAR SOUTHWEST KANSAS WHERE THE PROBABILITY OF WESTERLY
MOMENTUM MIXING DOWN TO THE SURFACE IS BEST (LEADING TO WARMER
TEMPERATURES).

SATURDAY THROUGH TUESDAY:

THE MINOR NORTHWEST FLOW SHORTWAVE TROUGH FRIDAY/FRIDAY NIGHT WILL
MOVE RAPIDLY SOUTHEAST ACROSS THE PLAINS INTO THE MISSISSIPPI VALLEY
WITHOUT MUCH FANFARE AND UPPER RIDGING WILL DEVELOP ACROSS THE
ROCKIES AND INTERMOUNTAIN WEST. LEE TROUGH WILL DEVELOP SATURDAY
NIGHT INTO SUNDAY AS YET ANOTHER WEAK...LOW AMPLITUDE SHORTWAVE
TROUGH MOVES ACROSS THE ROCKIES. QUITE A BIT OF DOWNSLOPE MOMENTUM
IN THE 850-700MB LAYER SATURDAY AND SUNDAY WILL LEAD TO WARM SURFACE
TEMPERATURES IN THE MID TO UPPER 50S. ANY WIND SHIFT TO THE
NORTHWEST DURING THIS TIME FRAME WILL PROVIDE LITTLE OR NO
TEMPERATURE FLUCTUATION GIVEN THE DEGREE OF DOWNSLOPE MOMENTUM AND
HELPING KEEP THE TRUE CANADIAN/ARCTIC AIRMASS ACROSS THE
NORTHEASTERN PLAINS AND UPPER MIDWEST REGION. MEAN RIDGING EARLY
NEXT WEEK ACROSS THE INTERMOUNTAIN WEST/ROCKIES WILL KEEP THE
SENSIBLE WEATHER ACROSS WESTERN KANSAS MILD AND DRY (TEMPERATURES IN
THE UPPER 50S TO PERHAPS LOWER 60S DURING THE AFTERNOON).

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 514 PM CST TUE JAN 29 2013

MID LEVEL FORCING AHEAD OF AN UPPER LEVEL TROUGH CAN BE EXPECTED
ACROSS ALL OF WESTERN KANSAS EARLY THIS EVENING. THIS WILL PRODUCE
A PERIOD OF SNOW ALONG WITH IFR CEILING AND/OR VISIBILITIES EARLY
TONIGHT. LATEST HRRR AND RAP SUGGESTS THIS BAND OF STEADIER
PRECIPITATION WILL END AT GCK AROUND 02Z AND HYS/DDC AROUND 05Z.
LATEST 18Z BUFR SOUNDINGS INDICATED SOME SUBSIDENCE AND DRIER AIR
WILL DEVELOP AFTER MIDNIGHT AS THE UPPER LEVEL TROUGH MOVES INTO
CENTRAL KANSAS. MVFR CIGS CAN BE EXPECTED AFTER 03Z WITH VFR CIGS
LIKELY AT ALL THREE TAF SITES BY 09Z. GUSTY NORTHWEST WINDS WILL
CONTINUE IN THE 15 TO 20 KNOT RANGE OVERNIGHT.

.PRELIMINARY POINT TEMPS/POPS...
DDC 21 38 22 48 / 80 0 0 0
GCK 17 38 22 50 / 90 0 0 0
EHA 18 40 25 54 / 70 0 0 0
LBL 19 41 23 56 / 50 0 0 0
HYS 17 34 19 37 / 90 0 0 0
P28 21 39 23 48 / 80 0 0 0

.DDC WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 PM CST /8 PM MST/ THIS EVENING
FOR KSZ030-031-043>045-061>063-074-075.

SYNOPSIS...RUSSELL
SHORT TERM...RUSSELL
LONG TERM...UMSCHEID
AVIATION...BURGERT

AREA FORECAST DISCUSSION

NWS GOODLAND KS

1251 PM MST MON JAN 28 2013

.UPDATE...
ISSUED AT 1249 PM MST MON JAN 28 2013

REMOVED THOMAS...SHERIDAN AND GRAHAM COUNTIES FROM THE DENSE FOG
ADVISORY. WILL PROBABLY BE ABLE TO REMOVE RAWLINS...DECATUR AND
NORTON NEXT HOUR.

TEMPERATURES ARE WARMING INTO THE 60S OUTSIDE OF THE FOG AREAS.
SOUTHWEST WINDS WILL INCREASE TO 20 TO 30 MPH WITH HIGHER
GUSTS. IT WILL BE MARGINAL FOR A WIND ADVISORY AND DO NOT PLAN ONE
UNLESS WINDS INCREASE MORE. RH VALUES ARE STAYING ABOVE 20 PERCENT
SO DO NOT THINK FIRE WEATHER WILL BE A CONCERN.

MEANWHILE...COLD FRONT IS APPROACHING NORTHWEST YUMA COUNTY
SLIGHTLY AHEAD OF SCHEDULE. PRECIPITATION IS HANGING BACK IN
WYOMING WELL BEHIND THE FRONT...BUT THERE IS FOG/STRATUS IN THE
NEBRASKA PANHANDLE AND THAT MIGHT REACH THE NORTHWEST FORECAST
AREA LATER THIS AFTERNOON.

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 401 AM MST MON JAN 28 2013

ONCE AGAIN THERE ARE NUMEROUS FORECAST PROBLEMS TO ADDRESS THROUGH
THE SHORT TERM. SATELLITE SHOWING A COMPLICATED AND AMPLIFIED FLOW
FROM THE PACIFIC INTO WESTERN NORTH AMERICA. RATHER STRONG/COLD AND
POSITIVELY TILTED TROUGH IS APPROACHING FROM THE WEST THIS MORNING.
COOL AND MOIST AIR MASS OVER THE AREA THIS MORNING IS EXPECTED TO
GIVE WAY TO A WARMER AIR MASS THAT IS NOT TOO FAR AWAY.

AT JET LEVEL...THE ECMWF AND CANADIAN WERE DOING A LITTLE BETTER
THAN THE OTHERS WITH THE JET SEGMENT THAT IS GETTING CLOSER TO US.
THAT OUTPUT WAS A LITTLE TOO FAR EAST. MODELS INITIALIZED WELL AT
MID LEVELS. AT THE SURFACE...THE MODELS TENDED TO HAVE THE FRONT TO
OUR SOUTH AND THE SURFACE TROUGH TO OUR WEST...TO FAR NORTH AND
EAST. THE SREF WAS DOING A LITTLE BETTER THAN THE ECMWF AND NAM. THE
RUC AND HRRR ARE CATCHING THE FOG WITH THE NAM NOT HAVING A CLUE
ABOUT IT LIKE LAST NIGHT. THE SREF IS DOING BEST ON THE LOW LEVEL
THERMAL FIELD AND IS A LITTLE BETTER THAN THE UKMET...ECMWF...AND
GFS.

TODAY/TONIGHT...FIRST CONCERN WHICH THE EVENING SHIFT ALREADY
ADDRESSED HAS BEEN DENSE FOG. WILL CONTINUE TO MONITOR TRENDS. AT
THIS TIME WILL KEEP THE CURRENT AREA OF THE ADVISORY BUT THERE ARE
INDICATIONS THAT THE ADVISORY MAY NEED TO BE EXPANDED. BIG KEYS ON
THE MAX TEMPERATURES IS HOW FAST THE STRATUS/FOG RETREATS/ENDS AND
WHEN THE COLD FRONT LOOKS TO START MOVING IN THE NORTH. THE MODELS
ARE SLOWER WITH THE FRONT. RUC/HRRR HAVE A GOOD HANDLE ON THE
STRATUS/FOG AREA. IT LOOKS LIKE THE FAR NORTHEAST CORNER COULD NOT
CLEAR UNTIL LATER THIS AFTERNOON. IF THAT IS THE CASE...THE
TEMPERATURES I HAVE UP THERE WILL BE TOO WARM. SUFFICE TO SAY THERE
COULD BE A HUGE GRADIENT IN TEMPERATURES TODAY.

AND IF THAT IS NOT BAD ENOUGH...SOME MID AND HIGH LEVEL CLOUD COVER
WILL START INCREASE IN THE WEST IN THE AFTERNOON. COMPARING THE
RUC/HRRR TO THE BETTER 850 MB TEMPERATURE GUIDANCE WOULD SUPPORT
60S OVER AREAS THAT GET A LOT OF SUN...MAYBE EVEN 70 DEGREE READING.
AS SURFACE RIDGE MOVES AWAY AND SURFACE LOW OVER EASTERN
STRENGTHENS...GRADIENT IS EXPECTED TO TIGHTEN ALONG WITH MODERATE 3
HOUR PRESSURE FALLS. SO OVER THE SOUTHWEST PORTION OF THE AREA IT
COULD GET BREEZY TO WINDY. THIS MAY CAUSE SOME FIRE WEATHER ISSUES.
REFER TO THE FIRE WEATHER SECTION BELOW.

BY LATE AFTERNOON...THE RIGHT REAR QUADRANT OF THE JET WILL BE
AFFECTING THE SOUTHEAST HALF OF THE AREA. BY LATE EVENING THIS HAS
MOVED EAST OF THE AREA. THIS JET LIFT IS OUT OF PHASE WITH THE
DEEPER MOISTURE AND OTHER LIFT. AT THIS TIME ONLY EXPECT CLOUDS IN
THE AFTERNOON FOR MOST OF THE AREA THIS AFTERNOON.

AFTER THAT...ABOVE MENTIONED UPPER TROUGH...WITH RATHER COLD AIR
ALOFT...IS EXPECTED TO START MOVE THROUGH DURING THE NIGHT. ON THE
SOUTHERN END OF THIS TROUGH SPORADIC LIGHTNING STRIKES HAVE BEEN
DETECTED. AM CONCERNED THIS SYSTEM IS COMING IN A LITTLE STRONGER
THAN 00Z MODELS SHOWED DESPITE BEING AN OPEN WAVE AND MOVING
THROUGH RATHER QUICKLY. NEWER DATA COME IN WITH A LITTLE BETTER
MOISTURE PROFILE. AT THIS TIME THE NORTHWEST PORTION OF THE AREA
CAME IN WITH THE BEST MOISTURE...INSTABILITY...AND LIFT SETUP. SO
MADE THE HIGHEST POPS IN THERE DURING THE NIGHT. THE BEST
PARAMETERS DO NOT REALLY START COMING INTO THE AREA UNTIL LATE IN
THE EVENING. GRADIENT AND 3 HOUR PRESSURE RISES SUPPORT BREEZY TO
MAYBE WINDY BEHIND THE FRONT.

TUESDAY/TUESDAY NIGHT...TROUGH IS STILL TO THE WEST OF THE AREA AT
12Z WITH A RATHER STRONG PV ANOMALY INDICATED WITH IT.
TROUGH/ANOMALY MOVE ACROSS DURING THE DAY. DESPITE WHAT APPEARS NOT
THE BEST OF MOISTURE PROFILES...THE INSTABILITY AND STRENGTH OF
THIS SYSTEM HAS ME CONCERNED ABOUT MEASURABLE SNOW/PRECIPITATION. SO
RAISED POPS INTO THE 20 TO 30 PERCENT RANGE BUT COULD SEE THE
POSSIBILITY OF NEEDING HIGHER POPS. ALSO IF THERE ENDS UP BEING
MORE SNOW THAN I THINK...THERE COULD BE SOME BLOWING SNOW DUE TO THE
STRONG AND GUSTY WINDS. IT IS POSSIBLE THAT THE WINDS COULD GET
CLOSE TO WIND ADVISORY CRITERIA.

MODELS ARE COMING IN COLDER AND MORE EXTENSIVE CLOUD COVER. SO
REDUCED MAXES AND IF THE COLDER MODELS WORK OUT...I MAY BE TOO WARM.
ANOTHER SHORTWAVE TROUGH...WEAK JET LIFT AND A REINFORCING SHORT OF
COLD AIR COULD KEEP FLURRIES GOING THROUGH THE NIGHT.

WEDNESDAY/WEDNESDAY NIGHT...SO HOW COLD DOES IT REMAIN BEHIND
EXITING SYSTEM. MODELS IN GOOD AGREEMENT IN BRINGING IN MUCH COLDER
ONCE THE TROUGH HAS MOVED TO THE EAST. ALSO AN INDICATION THAT
THERE MAY BE MORE CLOUD COVER THAN INDICATED. SO LOWERED MAXES AGAIN.
AGAIN WITH STRONG CYCLONIC FLOW WITH EMBEDDED SHORTWAVES...FLURRIES
COULD BE A POSSIBILITY. THIS FLURRY ACTIVITY ENDS DURING THE
EVENING.

.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 253 AM MST MON JAN 28 2013

MODELS ARE IN FAIRLY GOOD AGREEMENT THROUGH THE EXTENDED FORECAST
PERIOD. THE LARGE UPPER LEVEL TROUGH ACROSS THE CENTRAL AND EASTERN
UNITED STATES WILL CONTINUE MOVING SLOWLY TO THE EAST AND AN UPPER
LEVEL RIDGE OF HIGH PRESSURE SHOULD BUILD IN FROM THE WEST TOWARDS
THE END OF THE WEEK. A SURFACE HIGH PRESSURE WILL ALSO BECOME A
PERSISTENT FEATURE ACROSS THE PLAINS. WITH A RIDGE OF HIGH
PRESSURE BUILDING IN AND PERSISTENT SURFACE HIGH...PRECIPITATION
CHANCES THROUGH MOST OF THE EXTENDED FORECAST APPEAR MINIMAL. THE
ONLY CHANCE WOULD BE ON THURSDAY AS A WEAK SHORTWAVE ROTATES
AROUND THE EDGE OF THE UPPER LEVEL TROUGH. MODELS HAVE BACKED OFF
ON THE COVERAGE AND QPF AMOUNTS ACROSS THE TRI-STATE AREA SO HAVE
MADE CHANGES IN THE FORECAST TO REFLECT THIS. AT THE PRESENT
TIME...NO PRECIPITATION IS MENTIONED.

THE TRICKY PORTION OF THE EXTENDED FORECAST CONCERNS THE HIGH
TEMPERATURES. ON THURSDAY...MODELS INDICATE A TIGHT TEMPERATURE
GRADIENT ACROSS THE REGION AS THE COLD FRONT THAT MOVES THROUGH ON
MONDAY NIGHT LINGERS. THERE ARE SLIGHT DIFFERENCES IN THE GRADIENT
LOCATION BETWEEN THE GFS...CANADIAN AND EUROPEAN MODELS. THE GFS
IS COOLER THAN THE EUROPEAN SOLUTION BY 7 TO 8 DEGREES AS A
RESULT. FOR FRIDAY THROUGH SUNDAY...A WARMING TREND IS EXPECTED
AS ALL MODELS SHOW TEMPERATURES AT 850 MB WARMING. MODELS ARE IN
BETTER AGREEMENT IN THIS TIME FRAME WITH GUIDANCE WITHIN A FEW
DEGREES EACH DAY. THE GENERAL PATTERN THAT MODELS ARE PROJECTING
IS VERY SIMILAR TO THE WARM SCENARIO THAT PLAYED OUT LAST WEEK.
RAISED HIGH TEMPERATURES EACH DAY AS A RESULT OF LAST WEEKS
WEATHER AND CONTINUED DROUGHT CONDITIONS. BOTH THE GFS AND
EUROPEAN MODELS SHOW 850 MB TEMPERATURES CREEPING UP TO 10 DEGREES
CELSIUS FOR SUNDAY...SO HAVE MADE SUNDAY THE WARMEST DAY IN THE
EXTENDED WITH HIGHS APPROACHING 60 FOR MOST OF THE REGION.

THANKS TO ALL FOR THE COLLABORATION.

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 456 AM MST MON JAN 28 2013

HRRR CONTINUES TO HANDLE STRATUS AND FOG FIELD VERY WELL. FOR
KGLD...IT LOOKS LIKE IFR/LIFR CONDITIONS WILL STAY TO THE EAST OF
THE SITE THIS MORNING. KGLD MAY GET SOME BRIEF CONDITIONS BEFORE
IMPROVING BY MID MORNING. OTHERWISE AT KGLD...AN UPPER LEVEL STORM
SYSTEM AND ASSOCIATED COLD FRONT WILL MOVE INTO THE AREA TONIGHT.
THIS WILL SPREAD MVFR AND POSSIBLE IFR CONDITIONS INTO THE AREA
BEGINNING AROUND 04Z. MAY BE SOME SNOW AROUND HOWEVER CHOSE TO
HANDLE WITH VCSH SINCE TOWARD THE END OF THE PERIOD.

FOR KMCK...LIFR CONDITIONS WILL LAST THROUGH LATE MORNING BEFORE
IMPROVEMENT. IT IS POSSIBLE IFR/MVFR CONDITIONS COULD LAST A FEW
HOURS BEYOND THIS BUT LATER SHIFTS CAN ADDRESS WHEN IT BECOMES
MORE CLEAR. STORM SYSTEM AND COLD FRONT MOVE INTO THE AREA LATER
THIS EVENING. THIS WILL BRING IFR TO MVFR CEILINGS BACK TO THE
AREA WITH LIGHT SNOW SHOWERS POSSIBLE AS WELL.

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR KSZ002>004.

CO...NONE.
NE...DENSE FOG ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR NEZ080-081.

UPDATE...024
SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...BULLER

AREA FORECAST DISCUSSION

NWS GOODLAND KS

1216 PM MST MON JAN 28 2013

.UPDATE...
ISSUED AT 1208 PM MST MON JAN 28 2013

REMOVED LOGAN AND GOVE COUNTIES FROM THE DENSE FOG ADVISORY. THE
FOG AND STRATUS IS QUICKLY ERODING NORTH TO SOUTH...WILL PROBABLY
BE ABLE TO CANCEL THOMAS...SHERIDAN AND GRAHAM COUNTIES NEXT HOUR.

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 401 AM MST MON JAN 28 2013

.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 253 AM MST MON JAN 28 2013

THANKS TO ALL FOR THE COLLABORATION.

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 456 AM MST MON JAN 28 2013

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR KSZ002>004-
014>016.

CO...NONE.
NE...DENSE FOG ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR NEZ080-081.

UPDATE...024
SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...BULLER

AREA FORECAST DISCUSSION

NWS GOODLAND KS

1214 PM MST MON JAN 28 2013

.UPDATE...
ISSUED AT 1208 PM MST MON JAN 28 2013

REMOVED LOGAN AND GOVE COUNTIES FROM THE DENSE FOG ADVISORIES. THE
FOG AND STRATUS IS QUICKLY ERODING NORTH TO SOUTH...WILL PROBABLY
BE ABLE TO CANCEL THOMAS...SHERIDAN AND GRAHAM COUNTIES NEXT HOUR.

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 401 AM MST MON JAN 28 2013

.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 253 AM MST MON JAN 28 2013

THANKS TO ALL FOR THE COLLABORATION.

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 456 AM MST MON JAN 28 2013

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR KSZ002>004-
014>016.

CO...NONE.
NE...DENSE FOG ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR NEZ080-081.

UPDATE...024
SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...BULLER

AREA FORECAST DISCUSSION

NWS GOODLAND KS

1105 AM MST MON JAN 28 2013

.UPDATE...
ISSUED AT 1056 AM MST MON JAN 28 2013

EXTENDED DENSE FOG ADVISORY THROUGH 21Z FOR EASTERN AREAS. MAY BE
ABLE TO CANCEL A BIT EARLY ACROSS SOUTHERN TIER...LOGAN AND
GOVE...AS SATELLITE SHOWING FOG/STRATUS SLOWLY ERODING FROM NORTH
TO SOUTH.

ALSO ADJUSTED ALL WEATHER PARAMETERS IN NORTHEASTERN AREAS TO
ACCOUNT FOR LINGERING STRATUS/FOG. HIGH RESOLUTION SHORT TERM
MODELS SHOW THE CLEARING LINE WILL REACH THE KANSAS/NEBRASKA
BORDER SOME TIME LATE THIS AFTERNOON. MCCOOK TO NORTON AREAS MAY
NOT CLEAR OUT AT ALL AND CONSEQUENTLY SLASHED TEMPERATURES IN THE
NORTHEAST CORNER.

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 401 AM MST MON JAN 28 2013

.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 253 AM MST MON JAN 28 2013

THANKS TO ALL FOR THE COLLABORATION.

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 456 AM MST MON JAN 28 2013

.FIRE WEATHER...
ISSUED AT 401 AM MST MON JAN 28 2013

THE SOUTHWEST PORTION...ESPECIALLY FAR WESTERN CHEYENNE AND KIT
CARSON COULD REACH CRITICAL FIRE WEATHER CONDITIONS. AT THIS TIME
IT LOOKS LIKE THE RELATIVE HUMIDITIES STAY ABOVE 20 PERCENT WITH
ADEQUATE WINDS NOT LASTING THREE HOURS. SO ISSUED NO HIGHLIGHT FOR
THIS. BUT DAY SHIFT WILL NEED TO WATCH THIS.

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR KSZ002>004-
014>016-028-029.

CO...NONE.
NE...DENSE FOG ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR NEZ080-081.

UPDATE...024
SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...BULLER

AREA FORECAST DISCUSSION

NWS WICHITA KS

1150 AM CST MON JAN 28 2013

.AVIATION...18Z TAFS KRSL/KSLN/KHUT/KICT/KCNU

IFR CONDITIONS SHOULD RAPIDLY IMPROVE AROUND KRSL AT START OF THE
FORECAST. VISIBLE SATELLITE LOOP SHOWS BACK EDGE OF FOG/STRATUS
JUST SOUTH OF THE AIRPORT. LOW LEVEL MOISTURE WILL CONTINUE TO
ADVECT NORTH ACROSS SOUTHEAST KS AND SUSPECT MVFR OR POSSIBLY LOW
END VFR WILL PERSIST THROUGHOUT THE AFTERNOON AT KCNU. GUSTY WINDS
ARE EXPECTED MOST LOCATIONS THROUGH AT LEAST SUNSET. THE LOW
CLOUDS MAY BRIEFLY CLEAR AS DRY SLOT DEVELOPS AHEAD OF COLD FRONT.
THE COLD FRONT SHOULD MAKE IT THROUGH KRSL/KSLN ON TUE MORNING.
-HOWERTON

.PREV DISCUSSION... /ISSUED 539 AM CST MON JAN 28 2013/

AVIATION...12Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
VERY POOR AVIATION CONDITIONS WILL AFFECT ALL OF CENTRAL KANSAS
THIS MORNING...WITH DENSE FOG BLANKETING THE REGION. THE FOG WILL
BEGIN TO LIFT AS A WARM FRONT MOVES NORTHWARD INTO CENTRAL KANSAS
AROUND NOON. SOUTH WINDS WILL INCREASE DURING THE AFTERNOON HOURS
AND BECOME GUSTY AS SURFACE LOW PRESSURE DEEPENS OVER WESTERN
KANSAS TODAY. MEANWHILE...A COLD FRONT WILL SINK SOUTHWARD INTO
CENTRAL KANSAS LATE TONIGHT ALONG WITH SOME MVFR CIGS JUST BEHIND
THE FRONTAL BOUNDARY.

JAKUB

PREV DISCUSSION... /ISSUED 328 AM CST MON JAN 28 2013/

DISCUSSION...
FORECAST CONCERNS...DENSE FOG TRENDS THIS MORNING THEN
CONVECTIVE CHANCES TONIGHT INTO TUESDAY.

TODAY-TUESDAY
COMBO OF RADIATIONAL AND ADVECTION FOG DEVELOPING IN VICINITY OF
THE SURFACE FRONTAL BOUNDARY WHICH HAS BECOME QUASI-STATIONARY
ACROSS THE AREA. THE LATEST RUC WOULD SUGGEST BETTER POTENTIAL
FOR DENSE FOG WILL BE REALIZED JUST NORTH OF WICHITA AREA ACROSS
CENTRAL KANSAS AS MOIST ADVECTION WITH FRONT DRIFTS SLOWLY NORTH
DURING THE MORNING. A DENSE FOG ADVISORY WILL BE ISSUED FOR THESE
AREAS. OTHERWISE NEAR RECORD WARMTH EXPECTED THIS AFTERNOON WITH
WICHITA/CHANUTE AND SALINA POSSIBLY SETTING NEW RECORDS FOR THE
DATE. SOUTH WINDS WILL ALSO PICK UP IN THE WARM SECTOR THIS
AFTERNOON THOUGH SHOULD REMAIN BELOW WIND ADVISORY LEVELS. THE
WARM/MOIST SOUTHERLY FLOW WILL RESULT IN MODEST INSTABILITY ACROSS
SOUTHEAST KANSAS BY THIS EVENING WHERE DEEP LAYER SHEAR PROFILES
WILL ALSO INCREASE. IF CONVECTION CAN DEVELOP A FEW STRONG TO
MARGINALLY SEVERE STORMS WILL BE POSSIBLE. BROAD SCALE FORCING FOR
ASCENT WILL RESIDE ACROSS THE WARM/MOIST SECTOR ACROSS SOUTHEAST
KANSAS ON TUESDAY AHEAD OF THE UPPER TROF. WILL CONTINUE TO
HIGHLIGHT SLIGHT RISK FOR SEVERE STORMS THOUGH LATEST FRONTAL
TIMING WOULD SUGGEST BETTER CHANCES WILL SHIFT EAST OF THE AREA BY
LATE AFTERNOON OR EARLY EVENING. SOME LIGHT POST-FRONTAL PRECIP
IS POSSIBLE TUESDAY EVENING MAINLY ACROSS CENTRAL KANSAS...THOUGH
GENERALLY TRACE SPRINKLES TO FLURRIES.

WEDNESDAY
BACK TO SEASONABLY COLD AIR FOR MID-WEEK AS THE MEAN UPPER TROF
SHIFTS EAST FROM THE PLAINS ACROSS THE MIDWEST. LITTLE CHANGE TO
THE FORECAST WITH DRY WEATHER.

THURSDAY-SUNDAY
ADDITIONAL SHORTWAVE TROFS WILL ROTATE THROUGH THE EASTERN
CONUS LONGWAVE...HELPING TO REINFORCE THE CHILLY AIR ACROSS
THE PLAINS ON THURSDAY...WITH GRADUAL TEMPERATURE MODERATION
EXPECTED BY THE WEEKEND.

DARMOFAL

.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 73 48 57 25 / 10 10 10 10
HUTCHINSON 73 43 52 23 / 10 10 10 10
NEWTON 72 46 53 23 / 10 10 10 10
ELDORADO 71 50 58 26 / 10 10 10 10
WINFIELD-KWLD 74 52 63 27 / 10 10 10 10
RUSSELL 69 35 43 20 / 10 10 10 10
GREAT BEND 71 37 44 20 / 10 10 10 10
SALINA 70 40 47 22 / 10 10 10 10
MCPHERSON 72 42 50 22 / 10 10 10 10
COFFEYVILLE 73 59 67 32 / 10 30 60 10
CHANUTE 73 57 63 29 / 10 30 50 10
IOLA 73 57 63 28 / 10 30 50 10
PARSONS-KPPF 73 58 65 30 / 10 30 60 10

.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

1144 AM CST MON JAN 28 2013

...UPDATED FOR AVIATION...

.SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 313 AM CST MON
JAN 28 2013

THE BIGGEST CHALLENGE TO THIS FORECAST IS HOW FAR SOUTHWEST WILL ANY
DENSE FOG DEVELOP.

THE SITES OF HLC, RSL, ICT, AND MCK HAVE ALL ALREADY BEEN DOWN TO
1/4SM IN DENSE FOG THIS MORNING. HYS HAS FLIRTED WITH 1SM AND GBD
IS DOWN TO 3SM AT 08Z. THE RUC AND HRRR SHORT TERM MODELS ARE
STRONG WITH FORECASTING LESS THAN A QUARTER OF A MILE FROM NEAR
SCOTT CITY DOWN TO PRATT. HAVE DECIDED TO GO WITH AN NPW DENSE
FOG ADVISORY FOR THIS AREA, UNTIL ABOUT 17Z. WINDS WILL CONTINUE
TO BE LIGHT AND VARIABLE UNTIL ABOUT 17Z, THEN WILL GRADUALLY
BECOME SOUTH OR SOUTHWEST AT 15 MPH GUSTING TO 20 MPH IN THE NPW
AREA. THIS SHOULD DISSIPATE THE FOG RAPIDLY. AS WINDS BECOME
STRONGER ACROSS SOUTHWEST KANSAS BY 18Z, GENERALLY IN THE
20G30MPH RANGE, WARM AIR JUST ABOVE THE SURFACE WILL MIX DOWN.
AT 850MB, THE DDC TEMP AT 00Z WAS 3C WARMER THAN YESTERDAY, AND
WAS AT +13C. A SWATH OF +14C AIR WAS OVER THE SOUTHERN TIER OF
COUNTIES NEAR THE OKLAHOMA BORDER. THUS, I THINK HIGHS WILL REACH
LEVELS SIMILAR TO YESTERDAY ALONG THE OKLAHOMA BORDER, WHERE A
RECORD HIGH WAS SET AT P28 AT 74F. THE AREAS IN THE NORTH AND
NORTHEAST, WHICH WILL HAVE A DELAYED PERIOD FOR HEATING DUE TO LOW
CLOUDS AND FOG THIS MORNING, SHOULD ONLY SEE HIGHS IN THE UPPER
60S.

AS FOR TONIGHT, THE WINDS WILL STAY IN THE 10 TO 15 MPH RANGE
THROUGH ABOUT MIDNIGHT, THEN WILL DROP TO AROUND 10 MPH. A
PRE-FRONTAL TROUGH WILL SLIDE THROUGH TO THE SOUTHEAST AND SWITCH
WINDS TO THE NORTH AT 10 TO 15 MPH, FIRST IN THE SCOTT CITY AREA
AND A LITTLE LATER IN THE GARDEN CITY AND DODGE CITY AREAS. COOL
AIR WILL DROP INTO THE AREA NORTHWEST OF A LIBERAL TO DODGE CITY
TO LA CROSSE LINE LATE TONIGHT. MINIMUMS THERE WILL AVERAGE IN
THE UPPER 20S TO LOWER 30S. THE PRE-FRONTAL TROUGH WILL NOT REACH
THE PRATT, MEDICINE LODGE AND COLDWATER AREAS PRIOR TO 12Z
TUESDAY, SO MINIMUMS IN THOSE AREAS WILL STAY ELEVATED IN THE MID
40S. SOME HIGH CLOUDS WILL MOVE IN BEHIND THE WIND SHIFT, BUT
SHOULD NOT BE THICK ENOUGH TO HAVE MUCH INFLUENCE ON THE MINIMUM
TEMPERATURES.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 301 AM CST MON JAN 28 2013

MEDIUM RANGE MODELS INDICATE A STRONG UPPER LEVEL TROUGH OF LOW
PRESSURE TRACKING EASTWARD ACROSS THE WESTERN HIGH PLAINS TUESDAY
BRINGING THE POSSIBILITY FOR PRECIP GENERALLY FROM THE NORTHERN
PLAINS SOUTHWARD INTO CENTRAL AND EAST TEXAS. AN ATTENDANT COLD
FRONT IS PROJECTED TO PUSH THROUGH WESTERN KANSAS EARLY TUESDAY
MORNING PROVIDING THE FOCUS FOR INCREASED LIFT NEAR THE SURFACE.
HOWEVER, A STRONG SOUTHWESTERLY LOW LEVEL FLOW ACROSS ALL OF
CENTRAL AND SOUTHWEST KANSAS MONDAY WILL KEEP A VAST POOL OF
GULF MOISTURE BLOCKED OFF TO OUR EAST AND SOUTHEAST FROM EAST
TEXAS NORTHEAST INTO MISSOURI. THIS WILL HINDER PRECIP CHANCES
ACROSS WESTERN KANSAS TUESDAY. STILL, STRONG FAVORABLE DYNAMICS
ALOFT COMBINED WITH JUST ENOUGH MID LEVEL MOISTURE MAY SUPPORT
A FEW FLURRIES ACROSS PORTIONS OF WESTERN KANSAS TUESDAY
AFTERNOON. DRIER CONDITIONS ARE LIKELY THROUGH THE END OF THE WEEK
AS THE UPPER LEVEL TROUGH KICKS OFF TO THE EAST WHILE UPPER LEVEL
RIDGING BEGINS TO TAKE HOLD IN THE INTERMOUNTAIN WEST LATE IN THE
PERIOD.

COOLER TEMPERATURES ARE LIKELY TUESDAY AS A STRONG COLD FRONT PUSHES
THROUGH WESTERN KANSAS BY EARLY AFTERNOON. COLDER AIR WILL SURGE
SOUTHWARD INTO WESTERN KANSAS BEHIND THE FRONT DROPPING H85
TEMPERATURES TO JUST BELOW 0C AS THE BOUNDARY MOVES THROUGH.
ALTHOUGH THERE IS STILL UNCERTAINTY AS IT PERTAINS TO THE TIMING OF
THE BOUNDARY PASSAGE, IT APPEARS HIGHS WILL BE REACHED BY MID TO
LATE MORNING ACROSS WEST CENTRAL KANSAS WHILE HIGHS ARE REACHED IN
SOUTH CENTRAL KANSAS BY EARLY TO MID AFTERNOON. AGAIN, TIMING OF
THE FRONT WILL BE KEY, BUT LOOK FOR HIGHS GENERALLY UP INTO THE
40S(F) WITH THE LOWER TO MID 50S(F) STILL POSSIBLE IN SOUTH CENTRAL
KANSAS JUST AHEAD OF THE FRONT. TEMPERATURES WILL REMAIN FAIRLY
COLD WEDNESDAY AS ARCTIC AIR ASSOCIATED WITH A SURFACE HIGH IN THE
NORTHERN PLAINS SPILLS SOUTH INTO THE CENTRAL PLAINS WITH H85
TEMPERATURES NEARING 10C BELOW ACROSS CENTRAL KANSAS NEAR THE I-70
CORRIDOR. THE GEM, GFS, AND ECMWF SHOW H85 TEMPERATURES CLOSER TO
0C IN EXTREME SOUTHWESTERN KANSAS. HIGHS MAY STRUGGLE TO REACH THE
30S(F) ACROSS CENTRAL KANSAS WEDNESDAY AFTERNOON WITH THE LOWER TO
MID 40S(F) EXPECTED IN FAR SOUTHWEST KANSAS. A GRADUAL WARMING
TREND IS THEN LIKELY THROUGH THE END OF THE WEEK AS UPPER LEVEL
RIDGING BEGINS TO DEVELOP IN THE INTERMOUNTAIN WEST LATE IN THE
PERIOD.

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1142 AM CST MON JAN 28 2013

BOUNDARY LAYER WARMING AND SUBSEQUENT MIXING HAS ERODED THE FOG AND
STRATUS LAYER NORTHWARD ACROSS THE AREA THIS MORNING. AS A RESULT,
CEILINGS OR RESTRICTIVE VISIBILITIES WILL NO LONGER BE AN ISSUE FOR
ANY OF THE SOUTHWEST KANSAS TERMINAL SITES. A COLD FRONT WILL MOVE
INTO WESTERN KANSAS BETWEEN 07 AND 10 UTC TUESDAY, TURNING WINDS
NORTHWEST.

.PRELIMINARY POINT TEMPS/POPS...
DDC 71 33 43 21 / 0 0 10 10
GCK 71 30 42 20 / 0 0 20 10
EHA 69 32 41 21 / 0 0 20 10
LBL 71 32 43 22 / 0 0 10 10
HYS 68 32 43 20 / 0 10 10 10
P28 75 44 55 24 / 0 0 10 10

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

SHORT TERM...BURKE
LONG TERM...JJOHNSON
AVIATION...RUSSELL

AREA FORECAST DISCUSSION

NWS GOODLAND KS

942 AM MST MON JAN 28 2013

.UPDATE...
ISSUED AT 940 AM MST MON JAN 28 2013

CLEARED WESTERN COUNTIES FROM DENSE FOG ADVISORY. THE REMAINING
COUNTIES WILL SEE IMPROVEMENT IN THE NEXT HOUR OR TWO FROM WEST TO
EAST.

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 401 AM MST MON JAN 28 2013

.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 253 AM MST MON JAN 28 2013

THANKS TO ALL FOR THE COLLABORATION.

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 456 AM MST MON JAN 28 2013

.FIRE WEATHER...
ISSUED AT 401 AM MST MON JAN 28 2013

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR KSZ002>004-014>016-
028-029.

CO...NONE.
NE...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR NEZ080-081.

UPDATE...024
SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...BULLER

AREA FORECAST DISCUSSION

NWS GOODLAND KS

738 AM MST MON JAN 28 2013

.UPDATE...
ISSUED AT 737 AM MST MON JAN 28 2013

1/4 MILE VISIBILITY REPORTED IN TRIBUNE...23SW OF GOODLAND...AND
BY COOP OBSERVERS IN CHEYENNE COUNTY COLORADO. ADDED THOSE
COUNTIES TO THE ONGOING DENSE FOG ADVISORY.

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 401 AM MST MON JAN 28 2013

.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 253 AM MST MON JAN 28 2013

THANKS TO ALL FOR THE COLLABORATION.

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 456 AM MST MON JAN 28 2013

.FIRE WEATHER...
ISSUED AT 401 AM MST MON JAN 28 2013

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY UNTIL 11 AM MST /NOON CST/ THIS MORNING FOR
KSZ002>004-013>016-027>029-041-042.

CO...DENSE FOG ADVISORY UNTIL 11 AM MST THIS MORNING FOR COZ092.

NE...DENSE FOG ADVISORY UNTIL 11 AM MST /NOON CST/ THIS MORNING FOR
NEZ079>081.

UPDATE...024
SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...BULLER

AREA FORECAST DISCUSSION

NWS GOODLAND KS

730 AM MST MON JAN 28 2013

.UPDATE...
ISSUED AT 729 AM MST MON JAN 28 2013

TRIBUNE IS SOCKED IN AT 1/4SM...SO ADDED GREELEY AND WICHITA
COUNTIES TO THE DENSE FOG ADVISORY.

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 401 AM MST MON JAN 28 2013

.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 253 AM MST MON JAN 28 2013

THANKS TO ALL FOR THE COLLABORATION.

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 456 AM MST MON JAN 28 2013

.FIRE WEATHER...
ISSUED AT 401 AM MST MON JAN 28 2013

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY UNTIL 11 AM MST /NOON CST/ THIS MORNING FOR
KSZ002>004-014>016-028-029-041-042.

CO...NONE.
NE...DENSE FOG ADVISORY UNTIL 11 AM MST /NOON CST/ THIS MORNING FOR
NEZ079>081.

UPDATE...024
SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...BULLER

AREA FORECAST DISCUSSION

NWS GOODLAND KS

509 AM MST MON JAN 28 2013

.UPDATE...
ISSUED AT 456 AM MST MON JAN 28 2013

HRRR CONTINUES TO HANDLE DENSE FOG AREA VERY WELL. CONSIDERING ITS
TRENDS AND WHAT I AM SEEING IN THE OBSERVATIONS...WILL BE ADDING
DUNDY TO THE DENSE FOG ADVISORY. SOMETHING TO DAY UPDATE GUY WILL
NEED TO CONSIDER IS LOWERING MAXES IN THE FAR NORTH AND NORTHEAST
IF STRATUS AND FOG ARE SLOWER TO ERODE THAN CURRENTLY EXPECT.

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 401 AM MST MON JAN 28 2013

.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 253 AM MST MON JAN 28 2013

THANKS TO ALL FOR THE COLLABORATION.

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 456 AM MST MON JAN 28 2013

.FIRE WEATHER...
ISSUED AT 401 AM MST MON JAN 28 2013

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR KSZ002>004-014>016-
028-029.

CO...NONE.
NE...DENSE FOG ADVISORY UNTIL 11 AM MST /NOON CST/ THIS MORNING FOR
NEZ079>081.

UPDATE...BULLER
SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...BULLER

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

600 AM CST MON JAN 28 2013

...UPDATE TO AVIATION...

.SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 313 AM CST MON
JAN 28 2013

THE BIGGEST CHALLENGE TO THIS FORECAST IS HOW FAR SOUTHWEST WILL ANY
DENSE FOG DEVELOP.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 301 AM CST MON JAN 28 2013

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 600 AM CST MON JAN 28 2013

AREAS OF DENSE FOG WILL CONTINUE TO DEVELOP AND SPREAD SOUTHWEST
ACROSS CENTRAL AND PORTIONS OF SOUTHWEST KANSAS THROUGH SUNRISE
THIS MORNING. IFR CONDITIONS ARE LIKELY AT KHYS AND KGCK...AND
POSSIBLE AS FAR SOUTH AS KDDC. THE FOG WILL THEN BEGIN TO
DISSIPATE GENERALLY AFTER 15Z GIVING WAY TO VFR CONDITIONS BY MID
DAY. AS FOR WINDS, AN AREA OF LOW PRESSURE WILL STRENGTHEN ACROSS
EASTERN COLORADO TODAY. AS A RESULT, LIGHT AND VARIABLE WINDS THIS
MORNING WILL BECOME SOUTH TO SOUTHWESTERLY INCREASING UP TO 20 TO
30KT BY EARLY THIS AFTERNOON. THE WINDS WILL SUBSIDE THIS EVENING.

.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 11 AM CST THIS MORNING FOR KSZ030-031-
043>046-064>066-079-081.

SHORT TERM...BURKE
LONG TERM...JJOHNSON
AVIATION...JJOHNSON

AREA FORECAST DISCUSSION

NWS WICHITA KS

539 AM CST MON JAN 28 2013

.AVIATION...12Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
VERY POOR AVIATION CONDITIONS WILL AFFECT ALL OF CENTRAL KANSAS
THIS MORNING...WITH DENSE FOG BLANKETING THE REGION. THE FOG WILL
BEGIN TO LIFT AS A WARM FRONT MOVES NORTHWARD INTO CENTRAL KANSAS
AROUND NOON. SOUTH WINDS WILL INCREASE DURING THE AFTERNOON HOURS
AND BECOME GUSTY AS SURFACE LOW PRESSURE DEEPENS OVER WESTERN
KANSAS TODAY. MEANWHILE...A COLD FRONT WILL SINK SOUTHWARD INTO
CENTRAL KANSAS LATE TONIGHT ALONG WITH SOME MVFR CIGS JUST BEHIND
THE FRONTAL BOUNDARY.

JAKUB

.PREV DISCUSSION... /ISSUED 328 AM CST MON JAN 28 2013/

DISCUSSION...
FORECAST CONCERNS...DENSE FOG TRENDS THIS MORNING THEN
CONVECTIVE CHANCES TONIGHT INTO TUESDAY.

WEDNESDAY
BACK TO SEASONABLY COLD AIR FOR MID-WEEK AS THE MEAN UPPER TROF
SHIFTS EAST FROM THE PLAINS ACROSS THE MIDWEST. LITTLE CHANGE TO
THE FORECAST WITH DRY WEATHER.

DARMOFAL

.ICT WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR KSZ032-033-
047>053-067-068-082.

AREA FORECAST DISCUSSION

NWS GOODLAND KS

401 AM MST MON JAN 28 2013

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 401 AM MST MON JAN 28 2013

.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 253 AM MST MON JAN 28 2013

THANKS TO ALL FOR THE COLLABORATION.

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1000 PM MST SUN JAN 27 2013

FOR KGLD...SOUTH TO SOUTHWEST WINDS AROUND 10KTS EXPECTED THROUGH
LATE MORNING MONDAY BEFORE INCREASING INTO THE 17G27KT RANGE BY
17Z AHEAD OF AN APPROACHING COLD FRONT. SHOULD SEE A DECREASE IN
WIND AROUND 00Z BEFORE SHIFTING TO THE NORTHWEST AROUND 04Z WITH
GUSTS AROUND 20KTS POSSIBLE. FIRST IMPACT TO AN OTHERWISE VFR
FORECAST IS STRATUS/FOG THAT IS FORECAST TO BACK IN TOWARD THE
TERMINAL IN THE 12Z-16Z TIMEFRAME. GIVEN THE MODELS GENERALLY DONT
GO FAR ENOUGH WEST WITH THE MOISTURE HAVE A TEMPO GROUP FOR VIS
AROUND 4SM. NEXT CHANCE FOR MVFR/IFR CONDITIONS WILL BE
IMMEDIATELY BEHIND THE FRONT MONDAY NIGHT WHERE CIGS AROUND 1500FT
EXPECTED.

FOR KMCK...CURRENTLY SEEING VFR CONDITIONS WITH VIS AROUND 4SM IN
MIST. CONFIDENCE IS HIGHER THAT CONDITIONS WILL DETERIORATE TO
IFR/VLIFR BY 10Z AND CONTINUE THROUGH 16Z OR SO IN FG WITH VIS
AROUND 1/4 MILE. CONDITIONS SHOULD RETURN TO VFR SHORTLY AFTER 16Z
ONLY TO FALL BACK INTO THE MVFR/IFR RANGE AFTER 02Z AS A COLD
FRONT MOVES THROUGH.

.FIRE WEATHER...
ISSUED AT 401 AM MST MON JAN 28 2013

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY UNTIL NOON CST MONDAY FOR KSZ002>004-014>016-
028-029.

CO...NONE.
NE...DENSE FOG ADVISORY UNTIL NOON CST MONDAY FOR NEZ080-081.

SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...DDT

AREA FORECAST DISCUSSION

NWS GOODLAND KS

253 AM MST MON JAN 28 2013

.UPDATE...
ISSUED AT 1025 PM MST SUN JAN 27 2013

HAVE ISSUED A DENSE FOG ADVISORY THAT IS IN EFFECT NOW THROUGH 11
AM MST MONDAY MORNING.

ASOS/AWOS SITES REPORTING VISIBILITIES FROM 1/4SM AT KHLC TO 2.5SM
AT KCBK. LATEST 03Z RUC/HRRR AND LOCAL WRF MODEL ALL AGREE THAT
THE DENSE FOG ALONG OUR FAR EASTERN FORECAST AREA WILL PUSH
WESTWARD THROUGH THE REST OF THE NIGHT AND CONTINUE THROUGH THE
MORNING MONDAY.

UPDATE ISSUED AT 745 PM MST SUN JAN 27 2013

KNRN (NORTON) REPORTING 1/4SM FG AT PRESENT TIME WHILE KHLC (HILL
CITY) AT 3SM. FORECAST CONCERNS FOR THE OVERNIGHT HOURS INTO EARLY
MONDAY MORNING REVOLVE AROUND EXTENT OF FOG AND THREAT FOR DENSE FOG.

HAVE BEEFED UP COVERAGE OF FOG WITH WIDESPREAD FOG EXPECTED FROM
ROUGHLY TRENTON OR MCCOOK SOUTH THROUGH OAKLEY AND GOVE TONIGHT
INTO EARLY MONDAY MORNING WHERE WINDS REMAIN LIGHT AND DECOUPLING
OCCURS. GIVEN THE OBSERVATIONS AT KNRN AT 1/4SM ALREADY HARD TO
DISCOUNT THE NEED FOR A DENSE FOG ADVISORY. WILL WATCH FOR TRENDS
AND EVALUATE 03Z RUC/LATEST HRRR MODEL RUNS BEFORE MAKING A
DECISION.

OTHERWISE SHOULD BE GENERALLY CLEAR OUTSIDE OF THE FOG ALTHOUGH
SOME MID AND HIGH CLOUDS START TO MOVE INTO FAR EASTERN COLORADO
TOWARD SUNRISE AND SLOWLY INCREASE IN COVERAGE DURING THE DAY.

.SHORT TERM...(THIS EVENING THROUGH MONDAY EVENING)
ISSUED AT 1258 PM MST SUN JAN 27 2013

LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOW POSITIVELY TILTED TROUGH
EXTENDING FROM BRITISH COLUMBIA TO CENTRAL CALIFORNIA...WITH SW FLOW
ACROSS THE INTER-MOUNTAIN WEST AND CENTRAL PLAINS. SUBSIDENCE IS IN
PLACE OVER CENTRAL KS AND CENTRAL CO WITH SEVERAL WEAK SHORTWAVES
OVER THE NORTHERN PLAINS. A SURFACE TROUGH IS IN PLACE OVER THE
CWA WITH A STALLED WARM FRONT JUST NORTHEAST OF THE CWA IN CENTRAL
NEBRASKA.

AREAS OF FOG/STRATUS MAY REDEVELOP OVERNIGHT TONIGHT PRIMARILY
ALONG THE STATIONARY FRONT IN NEBRASKA...AND THEN SPREAD SW INTO OUR
CWA. MOST GUIDANCE IS KEEPING FOG TO THE NORTH AND EAST OF THE
CWA...HOWEVER LATEST 24HR RUC IS SHOWING FOG/STRATUS OVERSPREADING
THE NE HALF OF CWA. WITH HIGHER TD VALUES POSSIBLY LINGERING ACROSS
THE NE HALF OF THE CWA AND LOW LEVELS DECOUPLING...THE RUC SOLUTION
SEEMS REASONABLE. ACROSS THE WEST AND SOUTH THE BL SHOULD BEGIN TO
DRY OUT OVERNIGHT WITH S/SW FLOW...SO FOG POTENTIAL SHOULD BE
MINIMAL CLOSER TO THE KS/CO STATE LINE.

AS UPPER LEVEL TROUGH IN THE WEST SHIFTS WEST AND ASSOCIATED COLD
FRONT PUSHES SOUTHEAST MONDAY...LEE TROUGH WILL STRENGTHEN WITH
STRONG WAA AND BREEZY CONDITIONS ACROSS THE CWA. HIGH TEMP FORECAST
IS COMPLICATED BY THE POSSIBILITY OF LINGERING STRATUS...AND
INCREASING CLOUDS AS COLD FRONT AND UPPER TROUGH APPROACH CWA LATER
IN THE AFTERNOON. WE COULD ALSO START TO SEE RAIN CHANCES INCREASE
LATE IN THE AFTERNOON ACROSS THE NORTH/NORTHWEST. FOR NOW I KEPT
HIGH TEMPS IN LINE WITH PREVIOUS FORECAST...WITH NEAR RECORD HIGHS
IN THE MID TO UPPER 60S ACROSS NW KANSAS...AND SLIGHTLY COOLER TEMPS
ACROSS THE NORTH.

.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 253 AM MST MON JAN 28 2013

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1000 PM MST SUN JAN 27 2013

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR KSZ002>004-014>016-
028-029.

CO...NONE.
NE...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR NEZ080-081.

UPDATE...99
SHORT TERM...DR
LONG TERM...RRH
AVIATION...99

AREA FORECAST DISCUSSION

NWS WICHITA KS

328 AM CST MON JAN 28 2013

.DISCUSSION...
FORECAST CONCERNS...DENSE FOG TRENDS THIS MORNING THEN
CONVECTIVE CHANCES TONIGHT INTO TUESDAY.

WEDNESDAY
BACK TO SEASONABLY COLD AIR FOR MID-WEEK AS THE MEAN UPPER TROF
SHIFTS EAST FROM THE PLAINS ACROSS THE MIDWEST. LITTLE CHANGE TO
THE FORECAST WITH DRY WEATHER.

DARMOFAL

.AVIATION...06Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
CIGS IN THE 1,000-1,500FT RANGE HAVE COVERED ALL OF E & SE KS
THIS EVE. AT 04Z...THESE CIGS ARE SPREADING SLOWLY W/SW TOWARD
CNTRL & SC KS. AS A WELL-DEFINED NEARLY STATIONARY FRONT THAT IS
MEANDERING ALONG & JUST NW OF THE TURNPIKE GRADUALLY
STRENGTHENS...MUCH WARMER...MOISTURE LADEN AIR WILL SPREAD ACROSS
CNTRL KS. KSLN & KRSL WILL EXPERIENCE VLIFR CIGS & VSBYS ~10-15Z
WITH REMAINING TERMINALS IN IFR STATUS THESE PERIODS. WITH A SFC
LOW DEVELOPING OVER SE WY/NE CO STRENGTHENING CONSIDERABLY AS IT
MOVES S ACROSS ERN CO...S/SW FLOW WILL INCREASE & WOULD QUICKLY
SCOUR STRATUS & FOG FROM THESE AREAS ~15Z WITH KCNU CLEARING ~21Z.

.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 73 48 57 24 / 10 10 10 10
HUTCHINSON 73 43 52 23 / 10 10 10 10
NEWTON 72 46 54 23 / 10 10 10 10
ELDORADO 71 50 58 26 / 10 10 10 10
WINFIELD-KWLD 74 52 63 27 / 10 10 10 10
RUSSELL 69 35 43 20 / 10 10 10 10
GREAT BEND 71 37 44 20 / 10 10 10 10
SALINA 70 40 47 22 / 10 10 10 10
MCPHERSON 72 42 50 22 / 10 10 10 10
COFFEYVILLE 73 59 66 32 / 10 30 60 10
CHANUTE 73 57 63 28 / 10 30 50 10
IOLA 73 57 63 28 / 10 30 50 10
PARSONS-KPPF 73 58 65 30 / 10 30 60 10

.ICT WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR KSZ032-033-
047>053-067-068-082.

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

322 AM CST MON JAN 28 2013

...UPDATED FOR THE SHORT TERM FORECAST...

.SYNOPSIS...
ISSUED AT 305 PM CST SUN JAN 27 2013

A BROAD UPPER LEVEL RIDGE REMAINED IN PLACE ACROSS MUCH OF THE
UNITED STATES TODAY, AS A SHARP AMPLIFYING POSITIVELY TILTED TROUGH
HELPED TO AMPLIFY THE RIDGE BY DIVING SOUTHEAST THROUGH THE PACIFIC
NORTHWEST. A 850-700 MB TROUGH WAS PRESENT ACROSS THE CENTRAL AND
HIGH PLAINS REGION OF KANSAS AND NEBRASKA. VERY WARM AIR ON THE
ORDER OF +12 TO +15 DEGREES C WAS BEING PULLED NORTH INTO SOUTH
CENTRAL KANSAS IN THE BOUNDARY LAYER. A 50 KNOT LOW LEVEL JET ALSO
CONTRIBUTED TO CLEARING SKIES THROUGH SUBSIDENCE OVER MOST OF
SOUTHWEST KANSAS THROUGH THE MORNING HOURS.

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 313 AM CST MON JAN 28 2013

THE BIGGEST CHALLENGE TO THIS FORECAST IS HOW FAR SOUTHWEST WILL ANY
DENSE FOG DEVELOP.

THE SITES OF HLC, RSL, ICT, AND MCK HAVE ALL ALREADY BEEN DOWN TO
1/4SM IN DENSE FOG THIS MORNING. HYS HAS FLIRTED WITH 1SM AND GBD
IS DOWN TO 3SM AT 08Z. THE RUC AND HRRR SHORT TERM MODELS ARE
STRONG WITH FORECASTING LESS THAN A QUARTER OF A MILE FROM NEAR
SCOTT CITY DOWN TO PRATT. HAVE DECIDED TO GO WITH AN NPW DENSE
FOG ADVISORY FOR THIS AREA, UNTIL ABOUT 17Z. WINDS WILL CONTINUE
TO BE LIGHT AND VARIABLE UNTIL ABOUT 17Z, THEN WILL GRADUALLY
BECOME SOUTH OR SOUTHWEST AT 15 MPH GUSTING TO 20 MPH IN THE NPW
AREA. THIS SHOULD DISSIPATE THE FOG RAPIDLY. AS WINDS IN OUR
SOUTHWEST FORECAST AREA, NEAR ELKHART, GCK AND DDC, BECOME EVEN
STRONGER BY 18Z, IN THE 20G30MPH RANGE, STRONG WARM AIR WILL MIX
DOWN. AS OPPOSED TO YESTERDAY WHEN A LOW LEVEL JET WAS OVER US,
TODAY THE WARM AIR IS ALREADY IN PLACE. AT 850MB, THE DDC TEMP AT
00Z WAS 3C WARMER THAN YESTERDAY, AND WAS AT +13C. A SWATH OF
+14C AIR WAS OVER THE SOUTHERN TIER OF COUNTIES NEAR THE OKLAHOMA
BORDER. THUS, I THINK HIGHS WILL REACH LEVELS SIMILAR TO
YESTERDAY ALONG THE OKLAHOMA BORDER, WHERE A RECORD HIGH WAS SET
AT P28 AT 74F. THE AREAS IN THE NORTH AND NORTHEAST, WHICH WILL
HAVE A DELAYED PERIOD FOR HEATING DUE TO LOW CLOUDS AND FOG THIS
MORNING, SHOULD ONLY SEE HIGHS IN THE UPPER 60S.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 301 AM CST MON JAN 28 2013

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1123 PM CST SUN JAN 27 2013

SURFACE HIGH PRESSURE WAS OVER WESTERN KANSAS EARLY THIS MORNING.
AS LIGHT AND VARIABLE WINDS AND CLEAR SKY CONDITIONS PREVAIL, SOME
DENSE FOG AND POSSIBLY SOME LOW STRATUS, PRODUCING IFR CONDITIONS,
ARE LIKELY IN THE KHYS TAF SITE, BETWEEN 08Z AND 13Z THIS
MORNING. AT KGCK AND KDDC, FOG IS NOT LIKELY TO BE AS DENSE, ONLY
IN THE 3SM TO 4SM BR MVFR CATEGORY. AFTER SUNRISE, THE FOG WILL
BURN OFF AND A LIGHT SOUTHWESTERLY FLOW WILL DEVELOP. AFTER 18Z,
A LEE SIDE TROUGH WILL PRODUCE SOUTH WINDS IN THE 18G26KT RANGE AT
ALL TAF SITES.

.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 11 AM CST THIS MORNING FOR KSZ030-031-
043>046-064>066-079-081.

SYNOPSIS...RUSSELL
SHORT TERM...BURKE
LONG TERM...JJOHNSON
AVIATION...BURKE

AREA FORECAST DISCUSSION

NWS GOODLAND KS

1026 PM MST SUN JAN 27 2013

.UPDATE...
ISSUED AT 1025 PM MST SUN JAN 27 2013

HAVE ISSUED A DENSE FOG ADVISORY THAT IS IN EFFECT NOW THROUGH 11
AM MST MONDAY MORNING.

UPDATE ISSUED AT 745 PM MST SUN JAN 27 2013

OTHERWISE SHOULD BE GENERALLY CLEAR OUTSIDE OF THE FOG ALTHOUGH
SOME MID AND HIGH CLOUDS START TO MOVE INTO FAR EASTERN COLORADO
TOWARD SUNRISE AND SLOWLY INCREASE IN COVERAGE DURING THE DAY.

.SHORT TERM...(THIS EVENING THROUGH MONDAY EVENING)
ISSUED AT 1258 PM MST SUN JAN 27 2013

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 1258 PM MST SUN JAN 27 2013

LONGWAVE TROUGH WILL BRING A CHANCE OF LIGHT SNOW TO MOST OF THE
AREA MONDAY NIGHT. BEST CHANCES WILL BE BEFORE MIDNIGHT...THEN
GRADUALLY WINDING DOWN THROUGH TUESDAY MORNING. TOTAL SNOW AMOUNTS
STILL ON TRACK TO BE AN INCH OR LESS...HIGHEST IN COLORADO.
NORTHWEST FLOW ALOFT WILL BE IN PLACE THE REMAINDER OF THE PERIOD.
VERY WEAK SYSTEM MAY BRING FLURRIES OR A LIGHT DUSTING WEDNESDAY
NIGHT AND THURSDAY...OTHERWISE IT WILL BE DRY. TEMPERATURES WILL
BE NEAR TO SLIGHTLY BELOW NORMAL EARLY IN THE PERIOD...BUT WARM TO
AROUND 10 DEGREES ABOVE NORMAL BY THE WEEKEND.

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1000 PM MST SUN JAN 27 2013

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY UNTIL NOON CST MONDAY FOR KSZ002>004-014>016-
028-029.

CO...NONE.
NE...DENSE FOG ADVISORY UNTIL NOON CST MONDAY FOR NEZ080-081.

UPDATE...99
SHORT TERM...DR
LONG TERM...024
AVIATION...99

AREA FORECAST DISCUSSION

NWS GOODLAND KS

1002 PM MST SUN JAN 27 2013

.UPDATE...
ISSUED AT 745 PM MST SUN JAN 27 2013

OTHERWISE SHOULD BE GENERALLY CLEAR OUTSIDE OF THE FOG ALTHOUGH
SOME MID AND HIGH CLOUDS START TO MOVE INTO FAR EASTERN COLORADO
TOWARD SUNRISE AND SLOWLY INCREASE IN COVERAGE DURING THE DAY.

.SHORT TERM...(THIS EVENING THROUGH MONDAY EVENING)
ISSUED AT 1258 PM MST SUN JAN 27 2013

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 1258 PM MST SUN JAN 27 2013

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1000 PM MST SUN JAN 27 2013

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&

UPDATE...99
SHORT TERM...DR
LONG TERM...024
AVIATION...99

AREA FORECAST DISCUSSION

NWS LOUISVILLE KY

832 PM EST TUE JAN 29 2013

.Mesoscale Forecast Update...
Issued at 830 PM EST Tue Jan 30 2013

Surface low is beginning to strengthen across Missouri as
upper-level energy pushes eastward. As of 800 PM, the cold front
extends southwest from Lake Michigan, through Illinois, Missouri,
and into Oklahoma. Convection has been ongoing this afternoon and
evening ahead of the front. While there were severe storms that
impacted the St. Louis metropolitan area earlier, but this has
diminished in strength as it currently pushes into central Illinois.
The airmass across central Illinois and into our area is still
fairly stable. Aircraft soundings confirm what the models have been
predicting, which is a low-level inversion. The main concern is the
convection ongoing across south-central Missouri and northern
Arkansas, which is showing better signs of organizing. As indicated
with the latest Mesoscale Discussion from SPC, this will likely be
the line that will continue to propagate east impacting our area
overnight. As this line approaches, the cap will weaken as theta-e
advection increases, which is evident with a few low-topped showers
developing around the region.

As advertised for several days now, the shear will be quite
impressive as the line gets into our area. Effective bulk shear
currently ahead of the line (across western KY) is 55+ knots, with
effective SRH up to about 500 m2/s2. All guidance continues to peg
high shear in a weakly unstable environment for us as this
convective line gets into our area. With the surface low
strengthening as it tracks northeast and 55+ knot winds at 1900 ft
AGL, would expect the severe potential to continue into southern
Indiana/central Kentucky. Damaging winds with the line will be the
main threat as it becomes better organized over the next few hours.
Embedded circulations within bowing segments will continue to be a
threat as well, so isolated tornadoes remain in play. Overall timing
has not changed, with models still showing slight timing
differences. Latest RAP is a tad slower than our current forecast,
but if the line surges with better cold pool forcing, then we are
pretty much on schedule.

Aside from the strong winds associated with the convection, gradient
winds continue to strengthen. Some gusts are currently around 30
knots, with stronger winds likely as this system approaches.

.Short Term (Tonight through Wednesday Night)...
Issued at 320 PM EST Tue Jan 29 2013

...Strong to Severe Storms Expected Early Wednesday Morning With
Wind Damage and Isolated Tornadoes Being The Main Threats...

Models continue to remain in good agreement on severe weather threat
for tonight, and upstream development is matching up well with
high-res forecasts. MSAS analysis at 19Z indicated a broad 998 mb
low, stretching from eastern OK to southwest MO. By 06Z tonight,
models forecast this low to drop to around 990 mb near KLOT and
continuing to deepen towards daybreak.

A powerful low-level jet will develop overnight in response to this
deepening. Models continue to indicate this jet will be on the order
of 70-80 knots at 850 mb. Gradient winds ahead of the main line
still are expected to be fairly gusty. Speeds are marginal for a
wind advisory, but guidance usually does not handle nighttime winds
as well in these situations, so will continue the wind advisory.

Temperatures remaining in the 60s through the night will mean that a
squall line that forms out of the storms to our west this afternoon
will find a favorable environment to maintain itself through the
forecast area. Low level wind shear is mostly unidirectional, but
storm relative helicities are very high. We may see some discrete
cells develop ahead of the line which would be able to take more
advantage of more southerly winds ahead of the line to produce
tornadoes. The line itself likely will produce damaging winds as
the strong winds aloft get mixed down. Also cannot rule out some
embedded tornadoes within the line in the stronger meso`s that form.

The threat for flash flooding seems less with each run, as the width
of the band thins out some. For now have QPF for the
tonight/Wednesday time period at around an inch, though isolated
higher amounts are possible. Area rivers should be able to handle
this water.

Guidance for winds behind the main line pick up again Wednesday
afternoon. Should we get any breaks in the clouds, we easily could
see another round of 30-40 knot winds, so current timing on the wind
advisory looks good. The cold front associated with this low
pressure system will not get into the region until late in the
afternoon Wednesday. West/northwest winds will stay up Wednesday
night as much colder air pours into the area. We may see a brief
period of snow as lingering precipitation ahead of the main upper
trough and nearer the front remains into the night. Accumulations
look minor at this point, mainly over the Bluegrass if at all.

.Long Term (Thursday through Tuesday)...
Issued at 325 PM EST Tue Jan 29 2013

A shortwave and weak surface boundary looks to move through the Ohio
Valley Thursday afternoon/evening, bringing a slight chance for
light rain/snow showers to south-central Indiana. Once the
temperatures drop below freezing that night, expect any rain showers
to change over to snow completely as central Kentucky and southern
IN gets locked under a cold, Canadian airmass. Since models appear
to be trending a bit cooler, have dropped min temps Thursday
overnight/Friday morning into the upper teens and lower 20s. These
temps don`t look to rebound above the freezing mark on Friday
afternoon so look for clearing skies as the disturbance moves off
toward the east and surface high pressure briefly drops in.

The next disturbance appears to begin affecting the northern and
western portions of the forecast area by Saturday morning with light
snow shower chances for the north and light rain showers elsewhere.
As the temps rise above freezing, any snow that does fall early on
should switch over to mostly rain as the entire thermal profile
warms up. Even though temps will fall back into the 20s overnight
Saturday, the precip should exit to the east before approaching the
freezing mark again.

For the remainder of the weekend, southerly flow will return to the
region, warming temps into the 40s and 50s Sunday-Monday. However,
the rain is anticipated to return ahead of a cold front Monday in
the form of rain. The rain should be out by the start of the day on
Tuesday with the frontal passage. This leads temps to take on a
non-diurnal curve on Tuesday as the warmest temps of the day should
occur early on. As always is the case for this time of year, any
changes to the thermal profile forecast could change precip types
but for now, there appears to be general model consensus in the
anticipated overall pattern for this time frame. Any snow that is
able to stick to surfaces should be very light in accumulations.

.Aviation (00Z TAF Issuance)...
Issued at 642 PM EST Tue Jan 29 2013

Deep upper-level trough over the Eastern Rockies will force a
surface low pressure system now over the southern Plains to
intensify and head quickly toward the Midwest this evening and
overnight. The pressure gradient is beginning to tighten ahead of
this low, with southerly winds starting to increase/gust. Latest
wind profile guidance from CWSU ZSE indicates low-level wind shear
is likely overnight, with 50-60 knots around 1900 feet AGL. So, will
continue LLWS for all TAF sites. Convection currently across
Illinois, Missouri, and Arkansas will form a more organized line of
thunderstorms as the surface low strengthens tonight. This line will
eventually move east through all TAF sites. Have put in the best
thoughts for timing the actual line. Added VCTS a couple hours prior
to account for any development ahead of the line. Some guidance
indicates there could be two lines of convection. Will hit the TAFs
harder when the line does approach. Expect MVFR cigs through most of
the night, with conditions not improving until mid-late morning
Wednesday. By late Wednesday afternoon, there could be low-topped
showers/thunderstorms on the back side of this system, so will
continue with VCSH through the end of the TAF period for now.

.Hydrology...
Issued at 300 AM EST Tue Jan 29 2013

No real changes in the forecast thinking on the hydrologic front.
An intense line of strong to severe thunderstorms is forecast to
move across the region late tonight and early Wednesday morning. In
addition to the threat of damaging winds, these storms will likely
produce heavy rainfall. Once the system pulls east on Wednesday
morning, a period of stratiform rainfall will likely persist for a
few hours.

Rainfall amounts averaging a little more than an inch in 6 hours
should be widespread. Isolated amounts of up to 2 inches are
possible. This rain could result in brief small stream flooding and
later rises on larger rivers. Any flooding that will occur should be
minor due to the fast nature of these storms. The rain will taper to
scattered showers Wednesday afternoon.

.LMK WATCHES/WARNINGS/ADVISORIES...
IN...WIND ADVISORY UNTIL 4 PM EST /3 PM CST/ WEDNESDAY FOR
INZ076>079-
083-084-089>092.

KY...WIND ADVISORY UNTIL 4 PM EST /3 PM CST/ WEDNESDAY FOR
KYZ023>032-
061-062-070>072.

WIND ADVISORY UNTIL 7 PM EST /6 PM CST/ WEDNESDAY FOR
KYZ033>043-
045>049-053>057-063>067-073>078-081-082.

Mesoscale........MJP
Short Term.......RJS
Long Term........lg
Aviation.........MJP
Hydrology........MJ/CMC

AREA FORECAST DISCUSSION

NWS JACKSON KY

1231 AM EST MON JAN 28 2013

.UPDATE...
ISSUED AT 638 PM EST SUN JAN 27 2013

LIGHT RAIN IS BECOMING MORE WIDESPREAD ACROSS CENTRAL KENTUCKY AND
HAVE OPTED TO INCREASE POPS UP TO NEAR 100 FOR MOST OF EASTERN
KENTUCKY TONIGHT GIVEN WHAT IS TAKING PLACE UPSTREAM. NEARLY ALL
MESONET/AWOS/ASOS OBSERVATIONS ARE RECORDING MEASURABLE RAIN...SO IT
LOOKS LIKE A SURE BET WE WILL SEE WIDESPREAD LIGHT RAIN THROUGH
MIDNIGHT. IT STILL LOOKS LIKE THINGS SHOULD TAIL OFF SHORTLY AFTER
MIDNIGHT. FORECAST UPDATE IS ALREADY OUT.

UPDATE ISSUED AT 534 PM EST SUN JAN 27 2013

UPDATED TO SLOW DOWN PRECIPITATION ONSET. IT LOOKS LIKE THINGS ARE
FINALLY STARTING TO SATURATE UP ENOUGH TO ALLOW FOR SOME LIGHT RAIN
IN THE MONTICELLO/SOMERSET AREA SHORTLY. OTHERWISE...IT WILL REMAIN A
SLOW PROCESS AS RAIN TRIES TO FIGHT TO THE LOW LEVEL DRY AIR. THE RAIN
SHOULD EVENTUALLY WIN OUT...BUT STILL QUESTIONABLE IF THE SOUTHEAST
WILL SEE MUCH IN THE WAY OF RAIN AS THERE WILL LIKELY BE A SOUTHEAST
TO NORTHWEST GRADIENT FOR PLACES THAT RECEIVE RAIN VERSES THOSE WHO
DO NOT. BASED ON LATEST RUC MODEL DATA...RAIN SHOULD BE ON THE WAY
OUT BY 06Z WITH DRIER CONDITIONS EXPECTED FOR THE SECOND HALF OF THE
NIGHT INTO TOMORROW MORNING.

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 310 PM EST SUN JAN 27 2013

CURRENT CONDITIONS ACROSS EASTERN KENTUCKY AS OF 20Z HAS PRECIP
BEGINNING TO ENTER THE AREA NEAR SOMERSET AHEAD OF A DEVELOPING WARM
FRONT. AT THIS POINT...SURFACE OBS HAVE SHOWN NO PRECIP MAKING IT TO
THE GROUND IN THE SOUTH. BASED ON THE PERSISTENCE OF THE MODELS
BRINGING IN THE PRECIP LATE THIS AFTERNOON AND INTO THE EARLY
EVENING...WILL KEEP A SLIGHT CHANCE INTO THIS EARLY AFTERNOON WITH
THE RAIN OVER SPREADING THE REST OF EASTERN KENTUCKY THIS EVENING.
EXPECT RAIN TO CONTINUE THROUGH THE NIGHT. CONCERNS WITH THE TIMING
OF THE PASSING WARM FRONT LOOK TO BE AROUND 12Z WITH A 30 TO 40 KNOT
LL JET OVERHEAD. THIS WILL LEAD TO SOME 20 KNOT SOUTHWEST WINDS
MIXING TO THE SURFACE FOR MONDAY. MORE SHOWERY PRECIP ENTERS THE AREA
BY MONDAY AFTERNOON AS EASTERN KENTUCKY WILL BE IN THE WARM SECTOR
FOR THE REST OF THE SHORT TERM. THE SURGE OF WARM AIR WILL BRING
HIGHS FOR MONDAY INTO THE LOWER 60S...NEARLY 5 DEGREES SHORT OF
RECORD VALUES. SHOWER ACTIVITY WILL CONTINUE THROUGH MONDAY NIGHT AS
WELL WITH MODELS HANDLING THE SET UP QUITE WELL.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 351 PM EST SUN JAN 27 2013

THE MODELS ARE IN PRETTY GOOD AGREEMENT WITH THE TIMING OF THE NEXT
FRONT. THE LEADING EDGE OF THE FRONT IS GOING TO BRING SOME SHOWERS
TO THE BLUEGRASS ON TUESDAY MORNING. AS THE FRONT GETS
NEARER...SHOWERS WILL SPREAD ACROSS EASTERN KENTUCKY DURING THE
TUESDAY EVENING. THE LATEST ECMWF IS SLOWING THIS DOWN A LITTLE...SO
WILL NOT BE SURPRISED TO SEE THE FRONT SLOW DOWN AS THE TIME GETS
NEARER. THE FRONT WILL ACTUALLY BE MOVING THROUGH THE AREA ON
WEDNESDAY MORNING. THE NAM BUFR WAS SHOWING THE BEST INSTABILITY TO
BE VERY NEAR THE FRONT ITSELF AND THIS IS WHERE THUNDERSTORMS WILL
BE MOST LIKELY. THERE IS VERY STRONG SHEAR WITH THE FRONT...HOWEVER
THE INSTABILITY IS MARGINAL...SO THE SEVERE POTENTIAL IS LOW...BUT
NOT ZERO. IF THE FRONT SLOWS DOWN...THE THE SEVERE POTENTIAL WILL BE
GREATER. WILL NEED TO BE VIGILANT TO SEE HOW THIS PLAYS OUT. ONCE THE
POST FRONTAL SHOWERS MOVE INTO WEST VIRGINIA BY TUESDAY MORNING...THE
WILL BE A SHORT RESPITE...UNTIL A CLIPPER SYSTEM MOVES THROUGH THE
AREA ON THURSDAY NIGHT. THE LOOKS TO BE A LIGHT SNOWFALL WITH ABOUT
AN INCH EXPECTED. THIS WOULD BE A STUDENTS DREAM AND GIVE THEM
ANOTHER THREE DAY WEEKEND. HIGH PRESSURE WILL THEN DOMINATE UNTIL
ANOTHER WEAK SYSTEM MOVES THROUGH THE AREA ON SATURDAY NIGHT. SO THIS
WILL BE AN ACTIVE PERIOD.

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1230 AM EST MON JAN 28 2013

AN AREA OF LIGHT RAIN SHOWERS WILL CONTINUE TO MOVE OUT OF EASTERN
KENTUCKY DURING THE OVERNIGHT HOURS. MOST OF THE RAIN NOW IS MOVING
ACROSS AN AREA NORTH OF A LINE FROM PIKEVILLE TO JACKSON TO STANTON.
BASED ON THE LATEST RADAR IMAGERY...THIS TREND WILL CONTINUE FOR THE
NEXT COUPLE OF HOURS...BY WHICH TIME MOST OR ALL OF THE RAIN SHOWERS
WILL HAVE MOVED OUT OF THE FORECAST AREA FOR THE NIGHT. THE NEXT SHOT
OF RAIN WILL ARRIVE IN THE AREA BETWEEN 17 AND 18Z TOMORROW...WITH
THE TAF SITES SEEING ACCUMULATING RAIN BETWEEN 20 AND 21Z. MVFR
CONDITIONS ARE EXPECTED TO PREVAIL AT THE TAFS SITES FOR THE NEXT FEW
HOURS AS WELL...BEFORE THE LOWER CLOUDS BREAKUP A BIT...GIVING WAY TO
BROKEN TO OVERCAST CLOUD LAYERS ABOVE 10K. A FEW TO SCATTERED LOW AND
MIDDLE LEVEL CLOUDS WILL LIKELY DRIFT ACROSS THE SKIES NEAR THE OR AT
THE TAF SITES UNTIL THE NEXT ROUND OF RAIN MOVES MONDAY AFTERNOON.
THE NEXT SHOT OF RAIN WILL BRING BORDERLINE MVFR CONDITIONS WITH IT
AS WELL. TOWARD THE END OF THE TAF PERIOD...FOG FORMATION WILL LEAD
TO MVFR CONDITIONS ONCE AGAIN AFTER THE NEXT ROUND OF RAIN MOVES OUT
OF THE AREA.

.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

UPDATE...KAS
SHORT TERM...SHALLENBERGER
LONG TERM....JJ
AVIATION...AR

AREA FORECAST DISCUSSION

NWS WAKEFIELD VA

132 PM EST MON JAN 28 2013

.SYNOPSIS...
A WARM FRONT LIFTS NORTH OF THE AREA THROUGH EARLY THIS AFTERNOON.
THE NEXT COLD FRONTAL PASSAGE IS EXPECTED LATE WEDNESDAY.

.NEAR TERM /THROUGH TONIGHT/...
TEMPS HAVE RISEN ABOVE FREEZING THIS MORNING...ALLOWING LIGHT
PRECIP TO BECOME MOSTLY RAIN...EXCEPT FOR A FEW REPORTS OF SLEET
ACROSS SE VA/NE NC. HAVE ALLOWED THE FREEZING RAIN ADVISORY TO
EXPIRE AS PLANNED THIS MORNING. AS THE WARM FRONT CONTINUES TO
LIFT TO THE NORTH AND THE SHORTWAVE PUSHES OFFSHORE...PRECIP WILL
QUICKLY COME TO AN END W TO E. LATEST RADAR RETURNS/OBS SHOW
PRECIP ALREADY ENDING ALONG AND W OF INTERSTATE 95. PRECIP
EXPECTED TO END ACROSS THE ERN FA AROUND NOON. ANOTHER WEAKER
SHORTWAVE/VORT MAX WILL TRACK THROUGH NRN VA THIS
AFTERNOON...RESULTING ADDITIONAL LIGHT PRECIP FOR THE NRN PORTIONS
OF THE ERN SHORE.

TEMPS WILL BE TRICKY TODAY RESULTS IN ABUNDANT CLOUD COVER/WEAK
MIXING IS EXPECTED TO TRUMP LOW LEVEL WAA. LOW LEVEL THICKNESS
VALUES FORECAST TO INCREASE 10M BY LATE AFTERNOON WITH H85 TEMPS
INCREASING TO AROUND +8C. WAA VISIBLE ON MORNING KWAL SOUNDING PER
AN INCREASE IN 850 TEMPS OF 15C OVER THE PAST 24 HRS. MADE MINOR
CHANGES TO THE INHERITED DAYTIME HIGHS...BUMPING TEMPS DOWN A DEG
OR TWO ACROSS THE W. OF INTEREST...LATEST RAP GUIDANCE ERODES THE
CLOUD DECK OVER THE PIEDMONT...ALLOWING TEMPS TO CLIMB INTO THE
MID 50S. HOWEVER...LATEST BUFR SOUNDINGS AND WAA SUGGESTS THIS
CLOUD COVER/WEDGE SETUP WILL GO NOWHERE OVERNIGHT. TEMPS FORECAST
TO ONLY FALL INTO THE LOW/MID 40S. CONTINUED WAA OVERNIGHT ALONG
WITH MOIST SOILS AND WEAK MIXING WILL RESULT IN AREAS OF DENSE
FOG/LOW STRATUS TONIGHT.

.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
WARM AIR QUICKLY STREAMS INTO THE AREA AS WARM FRONT SURGES
NORTHWARD. WITH WEAK MIXING EXPECTED MON NIGHT AND EARLY ON
TUESDAY WL NEED TO WATCH PROGRESS OF WEDGE ACROSS THE NORTHWEST,
BUT FOR NOW INCRIMENTALLY NUDGED TEMPS UPWARDS. OTHERWISE, ONCE
LLVL INVERSION GETS BROKEN, EXPECT MARKEDLY WARMER CONDS ON
TUESDAY AS SFC HIGH NUDGES FARTHER OFFSHORE AND WARM SW FLOW SETS
UP. LO TEMPS TNGT MNLY IN THE L/M40S. HIGHS TUE FM THE U50S TO
M60S. LO TEMPS TUE NGT FM THE M/U40S ON THE ERN SHR TO L/M50S
ELSW.

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
STRONG SHORTWAVE TROUGH AND ASSOCIATED SFC LOW WILL EJECT FROM THE
DEEP SOUTH INTO THE MID ATLANTIC REGION WEDNESDAY AFTERNOON. SFC LOW
WILL LOCATE OVER THE GREAT LAKES WITH THE COLD FRONT EXTENDING SW
INTO THE LOWER MS RIVER VALLEY. WHILE TIMING AND SPATIAL DIFFERENCES
STILL EXIST...ECMWF MORE AMPLIFIED AND SLIGHTLY SLOWER THAN GFS...A
WARM/WET/WINDY DAY IS ON TAP FOR THE FA. DEEP SWLY FLOW WILL RESULT
IN STRONG MOISTURE ADVECTION INTO THE REGION...ORIGINATING FROM THE
GULF OF MEXICO (EVIDENT IN 700MB THETA E RIDGE). PRECIP WATERS WILL
INCREASE TO AROUND 1.5" (OVER 2 STD ABOVE NORMAL FOR JANUARY).
COLD FRONT EXPECTED TO CROSS THE FA WED LATE AFTERNOON THROUGH
LATE WED NIGHT. DIVERGENCE ALOFT (RRQ OF 160+ KT 300MB JET) AND
VORT MAX/SHORTWAVE WILL PROVIDE FORCING FOR ASCENT ACROSS THE
REGION. MARGINAL LAPSE RATES...SHEAR AND LITTLE...IF ANY CAPE IN
THE MIXED PHASE LAYER WILL LIKELY LIMIT CHANCE OF THUNDER WEDS
AFTERNOON. WILL LEAVE OUT ANY MENTION OF THUNDER IN THE
GRIDS/ZONES FOR NOW...BUT MAY NEED TO BE ADDED LATER WHEN MODELS
HAVE A BETTER HANDLING ON THE DEVELOPING SYSTEM. HAVE INCREASED
POPS TO CATEGORICAL WEDS AFTERNOON/EVENING ACROSS THE REGION.
LIGHT SHOWERS WILL BE POSSIBLE WEDS MORNING/EARLY AFTERNOON ACROSS
THE PIEDMONT. ABUNDANT MOISTURE AND STRONG FRONTOGENETIC FORCING
COULD ALSO LEAD TO PERIODS OF MODERATE TO HEAVY RAINFALL ACROSS
THE REGION. QPF AMOUNTS FORECAST TO GENERALLY RANGE FROM ONE
QUARTER TO ONE HALF INCH WITH LOCALLY HIGHER AMOUNTS. PRECIP WILL
END QUICKLY W TO E EARLY THURS MORNING AS DEEP...DRY WLY FLOW
KICKS IN.

STRONG WAA AND INCREASING HEIGHT/THICKNESS VALUES IN ADVANCE OF THE
FRONT (850 TEMPS WARMING TO NEAR +14C) WILL RESULT IN A WARM/HUMID
DAY. WHILE DAYTIME MIXING WILL BE WEAK WITH LACK OF SUNSHINE...BL
WINDS WILL BE ENOUGH FOR SLY SFC WINDS 15 TO 20 MPH WITH GUSTS UP TO
25 MPH. WHILE CLOUD COVER/LACK OF STRONG MIXING WILL LIMIT TEMPS
FROM REACHING THEIR FULL POTENTIAL...HIGHS STILL EXPECTED TO REACH
INTO THE UPPER 60S/LOW 70S ACROSS THE FA.

IN WAKE OF THE DEPARTING SYSTEM...TROUGHING WILL REMAIN OVER THE
REGION THURSDAY AS HEIGHT/THICKNESS FALLS RESULT IN COLDER TEMPS
THURSDAY (MID 40S N TO MID 50S). ADDITIONAL ENERGY WILL DIVE DOWN
THE BACKSIDE OF THE TROUGH THURS AFTERNOON...LOCATING OVER THE OH
VALLEY FRIDAY MORNING AS A WEAK LEE SIDE SFC TROUGH DEVELOPS.
MOISTURE MAY BE A CONCERN...BUT HAVE OPTED TO MENTION SLIGHT
CHANCE/CHANCE POPS ACROSS THE FA. PTYPE WILL BE A CONCERN...WITH
SNOW SHOWERS POSSIBLE ACROSS THE NRN FA.

ARCTIC HIGH PRESSURE WILL BUILD OVER THE MID ATLANTIC FRIDAY NIGHT
INTO SATURDAY AS A CLIPPER SYSTEM DIVES OVER THE GREAT LAKES EARLY
SATURDAY. TEMPS EXPECTED TO REMAIN BELOW NORMAL THROUGH THE WEEKEND.

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
PRECIPITATION HAS LIFTED OFF TO THE NE OF THE REGION...AND LOW
CLOUDS AND VSBYS HAVE NOW MOVED OUT OF THE TAF SITES (ALTHOUGH IFR
CIGS ARE NOT FAR OFF FROM KSBY). EXPECT MAINLY VFR CONDITIONS
THROUGH 00Z THIS EVENING...ALTHOUGH SOME MVFR VSBYS MAY PERSIST AT
KSBY AND MVFR CIGS MAY BEGIN TO MOVE INTO SE VA/NE NC AFTER 20Z.

FOR TONIGHT...DUE TO AMPLE LOW LEVEL MOISTURE WILL TREND THE TAFS
DOWN TO IFR CIGS (< 1 K FT) DURING THE EVENING HRS. SW FLOW
TYPICALLY INHIBITS VSBYS FROM DROPPING DOWN TOO FAR SO FOR NOW
HAVE GENLY GONE WITH 3-5SM (ALTHOUGH IT MAY DROP MORE AFTER
MIDNIGHT AND CIGS MAY ALSO DROP DOWN TO < 500 FT). THE LOW LEVEL
SW TO W FLOW ON TUESDAY SHOULD GRADUALLY SCOUR OUT LOW LEVEL
MOISTURE BUT IT DOES NOT APPEAR THAT STRONG SO MAY TAKE AWHILE
(FOR NOW HAVE IFR CIGS IN TAFS THROUGH 16Z). FOG/LOW CLOUDS WILL
PROBABLY RETURN FOR SOME OF THE AREA TUE NIGHT. A STRONGER SSW
WIND ON WEDNESDAY SHOULD PRODUCE VFR CONDITIONS. THE ARRIVAL OF A
COLD FRONT LATE WED AFTN THROUGH EARLY THU MORNING WILL LIKELY PRODUCE
MVFR/IFR CONDITIONS IN SHRA. DRIER WNW FLOW THU.

.MARINE...
PER LATEST OBS AND TRENDS HAVE ADDED SCA HEADLINES TO MIDDLE BAY
ZONE SO NOW THE BAY NORTH OF NEW PT COMFORT IS COVERED W/ SCA
HEADLINES.

PREVIOUS DISCUSSION...
A WARM FRONT WILL LIFT NORTH OF THE REGION LATER THIS MORNING
ALLOWING FOR INCREASING SW FLOW. BY THIS AFTERNOON...SW WINDS OF
15-20 KT ARE EXPECTED ON THE OCEAN AND ALSO THE CENTRAL CHES BAY
NORTH OF WINDMILL PT AS THE LOW LEVEL PRESSURE GRADIENT TIGHTENS
BETWEEN DEPARTING HIGH PRESSURE AND LOW PRESSURE OVER THE EASTERN
GREAT LAKES. SOME GUSTS UP TO 25 KT ARE POSSIBLE NORTH OF
CHINCOTEAGUE LATE TODAY...BUT HAVE CAPPED WIND GUSTS BELOW SCA
THRESHOLDS ATTM AS CONFIDENCE NOT HIGH ENOUGH FOR AN SCA HEADLINE.
HOWEVER...HAVE RAISED AN SCA FOR THE CENTRAL CHES BAY NORTH OF
WINDMILL AS NEWEST HIGH-RES MODEL DATA INSISTS SW FLOW WILL INCREASE
TO 15-20 KT THIS AFTERNOON/EVENING. SW WINDS GRADUALLY TAPER OFF
LATE TONIGHT INTO EARLY TUESDAY. LIGHT S-SW FLOW IS ANTICIPATED ON
TUESDAY.

THE NEXT LOW PRESSURE SYSTEM AND ITS ASSOCIATED COLD FRONT WILL
APPROACH THE REGION FROM THE WEST LATE WEDNESDAY. AHEAD OF THE
FRONT...A STRONG LOW-LEVEL JET WILL DEVELOP OVER THE REGION AND THE
WATERS. WHILE THE STRONGEST WINDS WILL REMAIN ALOFT...ENOUGH WIND
SHOULD REACH THE WATER SFC TO WARRANT SCA CONDITIONS OVER ALL WATERS
FROM MID-MORNING WED INTO EARLY THURS MORNING. SEAS RAPIDLY BUILD
WED AFTERNOON...REACHING 8 TO 10 FT OUT AROUND 20 NM LATE. COLD
FRONT EXPECTED TO CROSS THE WATERS EARLY THURS MORNING ACCOMPANIED
BY MODEST CAA.

UNSETTLED WEATHER WILL CONTINUE THROUGH THE WEEKEND AS A SERIES OF
DISTURBANCES CROSS THE WATERS. ADDITIONAL SCA HEADLINES WILL LIKELY
BE NEEDED THURSDAY AND FRIDAY...AND POSSIBLY INTO THE WEEKEND.

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EST TUESDAY FOR ANZ630-631.

$$
SYNOPSIS...ALB
NEAR TERM...SAM
SHORT TERM...ALB/MAM
LONG TERM...SAM
AVIATION...LKB
MARINE...JDM/LKB

AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

1116 AM EST MON JAN 28 2013

.SYNOPSIS...
LOW PRESSURE CROSSING THE EASTERN GREAT LAKES WILL CAUSE RAINY
CONDITIONS TODAY. WARMER TREND IN TEMPERATURES WILL CONTINUE
THROUGH WEDNESDAY NIGHT BEFORE A STRONG COLD FRONT PASSES THROUGH
AND BRINGS BACK COOLER THAN NORMAL TEMPERATURES BY THE END OF THE WEEK.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TEMPERATURES IN THE PAST FEW HOURS HAVE WARMED TO ABOVE FREEZING
AND PRECIPITATION HAS TRANSITIONED TO ALL RAIN IN CWA WITH THE
EXCEPTION OF EXTREME NORTHEAST COUNTIES AND GARRETT COUNTY.

RECENT RADAR SHOWS A BAND OF SHOWERS ACROSS THE OHIO VALLEY INTO
PA...THEREFORE HAVE EXTENDED POPS THROUGH THE LATE AFTERNOON
ACROSS THE REGION.

LATEST RAP MODEL RUN SEEMED TO HAVE A GOOD GENERAL IDEA OF MAX TEMP
FOR TODAY AS NAM/GFS SEEMED TOO COOL AND PERHAPS DID NOT PICK UP
WELL ON WARM AIR ADVECTION.

AS DEW POINTS MOVE ABOVE FREEZING THIS AFTERNOON EXPECT WIDESPREAD
FOG TO DEVELOP A LITTLE AFTER SUNSET.

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
FRONTAL BOUNDARY WILL TRANSITION NORTHWARD THROUGH TUESDAY WITH
SHORTWAVES MOVING NORTHEAST ACROSS THE REGION. TIMING OF ANY
PARTICULAR SHORTWAVE WILL BE UNCERTAIN BUT WENT WITH A DECLINE IN
POPS TO CHANCE NUMBERS AS THE BOUNDARY IS PROJECTED WELL NORTH OF
THE AREA.

WIDESPREAD FOG IS ANTICIPATED ON MONDAY NIGHT GIVEN THE COLD GROUND
AND DEW POINTS MOVING INTO THE 40S. OTHERWISE...EXPECT A VERY MILD
TUESDAY WITH THE REGION UNDER A BROAD RIDGE IN AMPLIFIED FLOW.

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
THE LONG TERM FORECAST WAS CONSTRUCTED USING A ECMWF/GFSE BLEND...LEAVING
THE UPPER OHIO VALLEY IN AN UNSEASONABLY WARM AND MOIST...SOUTHWESTERLY
LOW-LEVEL FLOW TUESDAY NIGHT INTO WEDNESDAY AHEAD OF A STRONG COLD
FRONT. AN INITIAL SHORT WAVE WILL PUSH ACROSS THE AREA AHEAD OF
THE FRONT...WITH THE CHANCE OF RAIN INCREASING TO CATEGORICAL AS
THE FRONT APPROACHES FROM THE WEST ON WEDNESDAY.

IN THE WAKE OF THE FRONT...STRONG COLD ADVECTION IS EXPECTED TO
QUICKLY CHANGE PRECIPITATION OVER TO SNOW SHOWERS ON WEDNESDAY
NIGHT WITH SOME UPSLOPING SNOW ACCUMULATION POSSIBLE INTO THURSDAY.
COLD FLOW IS FORECAST TO CONTINUE INTO FRIDAY WITH SNOW SHOWER CHANCES
CONTINUING. SUB-ZERO WIND CHILL INDICIES AE POSSIBLE BY EARLY FRIDAY.

FOR THE WEEKEND...GFS/ECMWF INDICATE A CLIPPER SYSTEM DIVING
SOUTHEASTWARD ACROSS THE GREAT LAKES AND PUSHING INTO THE UPPER
OHIO VALLEY. HAVE GONE WITH CHC POPS OVER THE WEEKEND FOR THIS
POTENTIAL.

.AVIATION /16Z MONDAY THROUGH FRIDAY/...
SFC CHART SHOWS A WARM FRONT WAS WORKING NEWD THRU THE RGN.
WINTRY PCPN HAS BEGUN TO SWITCH TO RA FM SW-NE AND THIS SHOULD
CONT AS WARMER AIR MOVES IN. ALL FZRA SHOULD BE OVR AT PIT BY 14Z.
CONDS HAVE BEEN DCRG TO IFR ACRS MUCH OF THE RGN. CONDS COULD VARY
BTWN MVFR AND IFR AT TIMES THRU THE AFTN ALTHOUGH EXPTG IFR TO BE
PREDOMINATE COND. LLVL JET MOVG IN WL BRING LLWS CONDS AS WELL
THRU LT AFTN...WITH TEMP INVERSION LMTG MXG DOWN OF GUSTS TO THE
SFC. IFR EXPTD OVRNT IN LOW CIGS/BR. COULD SEE -DZ BUT KEPT OUT OF
FCST ATTM.

.OUTLOOK.../MONDAY NIGHT THROUGH FRIDAY/...
RESTRICTIONS WL CONT THRU TUE. PERIODIC RESTRICTIONS ARE PSBL WED
THRU FRI AS A COLD FRONT MOVES THRU AND COLD NW FLOW DVLPS BEHIND
IT.

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WINTER STORM WARNING UNTIL 5 PM EST THIS AFTERNOON FOR MDZ001.
OH...NONE.
PA...WINTER STORM WARNING UNTIL 5 PM EST THIS AFTERNOON FOR PAZ008-
009-015-016.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
PAZ007-013-014-020>023-073>076.
WV...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
WVZ023-041.

AREA FORECAST DISCUSSION

NWS WAKEFIELD VA

1011 AM EST MON JAN 28 2013

.SYNOPSIS...
A WARM FRONT LIFTS NORTH OF THE AREA THROUGH EARLY THIS AFTERNOON.
THE NEXT COLD FRONTAL PASSAGE IS EXPECTED LATE WEDNESDAY.

.AVIATION /15Z MONDAY THROUGH FRIDAY/...
A DISTURBANCE CROSSING THE REGION THIS MORNING WILL BRING SOME LIGHT
PRECIP TO THE TAF SITES THROUGH 18Z. WITH SFC TEMPERATURES AOB
FREEZING AT THE ONSET...COULD SEE SOME LIGHT WINTRY PCPN OF SN/PL/ZR
FOR MAINLY KRIC AND KSBY. CEILINGS WILL STRUGGLE TO DROP BELOW 2500
FT DEW TO THE LOW LEVEL DRY AIR SO THE LIGHT PCPN WILL BE FALLING
OUT OF SOME HIGHER DECKS AND VSBY WILL BE MAINLY ABOVE 5 MI. SFC
TEMPS SHOULD CLIMB ABOVE FREEZING BETWEEN 15Z AND 17Z AS THE
SOUTHERLY FLOW INCREASE TURNING ANY LINGER PCPN TO RAIN. FOR
PHF/ORF/ECG...THE LOW LEVEL DRY AIR BETWEEN THE SFC AND 5K FT WILL
INHIBIT MUCH OF THE PCPN FROM REACHING THE GROUND SO HAVE NOT
INCLUDED ANY MENTION IN THE FORECAST AS OF YET AND SFC TEMPS SHOULD
BE ABOVE FREEZING SHOULD ANY PCPN REACH THE GROUND. THE SHORTWAVE
SHOULD BE EXITING THE AREA BY 18Z WITH THE CLOUDS BREAKING UP DURING
THE AFTERNOON HOURS.

FOR TONIGHT...MODELS SHOWING SOME LOW LEVEL MOISTURE MOVING
NORTHEAST OUT OF THE CAROLINAS THAT COULD PRODUCE SOME MVFR STRATUS
CONDITIONS. THE INCREASING SOUTHERLY FLOW ON TUESDAY INTO WEDNESDAY
SHOULD PRODUCE VFR CONDITIONS. THE ARRIVAL OF A COLD FRONT LATER
WEDNESDAY INTO THURSDAY COULD PRODUCE MVFR/IFR CONDITIONS ONCE
AGAIN.

.MARINE...
A WARM FRONT WILL LIFT NORTH OF THE REGION LATER THIS MORNING
ALLOWING FOR INCREASING SW FLOW. BY THIS AFTERNOON...SW WINDS OF
15-20 KT ARE EXPECTED ON THE OCEAN AND ALSO THE CENTRAL CHES BAY
NORTH OF WINDMILL PT AS THE LOW LEVEL PRESSURE GRADIENT TIGHTENS
BETWEEN DEPARTING HIGH PRESSURE AND LOW PRESSURE OVER THE EASTERN
GREAT LAKES. SOME GUSTS UP TO 25 KT ARE POSSIBLE NORTH OF
CHINCOTEAGUE LATE TODAY...BUT HAVE CAPPED WIND GUSTS BELOW SCA
THRESHOLDS ATTM AS CONFIDENCE NOT HIGH ENOUGH FOR AN SCA HEADLINE.
HOWEVER...HAVE RAISED AN SCA FOR THE CENTRAL CHES BAY NORTH OF
WINDMILL AS NEWEST HIGH-RES MODEL DATA INSISTS SW FLOW WILL INCREASE
TO 15-20 KT THIS AFTERNOON/EVENING. SW WINDS GRADUALLY TAPER OFF
LATE TONIGHT INTO EARLY TUESDAY. LIGHT S-SW FLOW IS ANTICIPATED ON
TUESDAY.

UNSETTLED WEATHER WILL CONTINUE THROUGH THE WEEKEND AS A SERIES OF
DISTURBANCES CROSS THE WATERS. ADDITIONAL SCA HEADLINES WILL LIKELY
BE NEEDED THURSDAY AND FRIDAY...AND POSSIBLY INTO THE WEEKEND.

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EST TUESDAY FOR ANZ630.

$$
SYNOPSIS...ALB
NEAR TERM...SAM
SHORT TERM...ALB/MAM
LONG TERM...SAM
AVIATION...JDM
MARINE...JDM

AREA FORECAST DISCUSSION

NWS GRAND RAPIDS MI

958 PM EST TUE JAN 29 2013

.SYNOPSIS...
ISSUED AT 348 PM EST TUE JAN 29 2013

AREAS OF FOG WILL GIVE WAY TO HEAVY RAIN TONIGHT AS LOW PRESSURE
MOVES THROUGH. SOME FLOODING IS POSSIBLE. THE RAIN WILL MOVE EAST
ON WEDNESDAY WITH COLDER AIR MOVING IN ALONG WITH SOME RAIN
CHANGING TO SNOW. TEMPERATURES WILL CONTINUE TO FALL THROUGH
FRIDAY ALONG WITH LAKE EFFECT SNOW SHOWERS.

.UPDATE...
ISSUED AT 817 PM EST TUE JAN 29 2013

AT 0105Z THE KGRR 88D SHOWS RAIN AND ISOLATED THUNDERSTORMS. NO
SEVERE WX IS ANTICIPATED IN OUR AREA TONIGHT. LATEST HIGHER
RESOLUTION GUIDANCE SUCH AS THE 12Z 4KM WRF NMM INDICATES WE WILL
HAVE RAIN AND SCATTERED THUNDERSTORMS THROUGH THE OVERNIGHT
PERIOD. RAIN COULD BE HEAVY AT TIMES. THEREFORE NO HEADLINE
CHANGES ARE PLANNED/NECESSARY THIS EVENING AND THE FLOOD WATCH CONTINUES
IN EFFECT THROUGH WEDNESDAY AFTERNOON.

.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 348 PM EST TUE JAN 29 2013

AREAS OF PATCHY DENSE FOG WILL CONTINUE THIS EVENING ACROSS THE
NORTHERN ZONES UNTIL THE WARM FRONT LIFTS THROUGH. COVERAGE IS
VARIABLE ENOUGH TO NOT GO WITH A DENSE FOG ADVISORY BUT WILL HAVE
TO MONITOR OBS NEXT FEW HOURS.

FLOOD WATCH CONTINUES TONIGHT FOR ALL ZONES. MOST IF NOT ALL OF
THE SNOW IS GONE ACROSS THE CENTRAL AND SOUTHERN ZONES BUT SOME
SNOWMELT CONTRIBUTION REMAINS UP NORTH WHERE QPF IS EXPECTED TO BE
1 TO 2 INCHES. 12Z MODEL GUIDANCE SHIFTED NORTH WITH THE AXIS OF
HEAVIEST QPF ALTHOUGH THE HRRR HAS BEEN SHOWING THE MOST
CONVECTIVE...AND HEAVIER...RAINS FURTHER SOUTH AND EAST. SEE HYDRO
SECTION OF FORECAST FOR SPECIFICS ON RIVER FLOOD WARNINGS.

EXPECT THE HEAVIEST RAINS TO MOVE INTO WESTERN ZONES THIS EVENING
THEN MARCH STEADILY ACROSS THE FORECAST AREA OVERNIGHT...DEPARTING
THE EASTERN ZONES WEDNESDAY MORNING. THE DEFORMATION RAIN/SNOW
ZONE SHOULD BE REACHING THE NORTHWEST FORECAST AREA WEDNESDAY
MORNING. WILL HAVE TO WATCH THIS AREA FOR ACCUMULATING SNOW BY LATE
WEDNESDAY MORNING INTO THE AFTERNOON. COLD AIR ARRIVES IN THE
AFTERNOON WITH LAKE EFFECT KICKING IN WEDNESDAY NIGHT. EXPECT LAKE
EFFECT TO PENETRATE INLAND THURSDAY AND THURSDAY NIGHT WITH FLOW
GOING NORTHWEST TO WEST.

.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 348 PM EST TUE JAN 29 2013

THE ECMWF AND GFS ARE IN PRETTY GOOD AGREEMENT THROUGH THE WEEKEND.
BOTH MODELS SHOW THE DEEP UPPER TROUGH MOVING EAST AWAY FROM THE
AREA AND TAKING THE CORE OF THE COLD AIR WITH IT. THE DGZ IS ALREADY
GOING TO BE VERY LOW FRIDAY AND WITH THE COLD AIR MOVING AWAY WE/LL
SEE THE EASTERN EDGE OF THE LAKE EFFECT SNOW SHOWERS RETREATING
TOWARD THE LAKE SHORE AND THEN DIMINISHING FRIDAY NIGHT AND
SATURDAY.

THE NEXT CHC FOR SNOW AFTER THAT WILL BE MONDAY WHEN A CLIPPER
MOVES TOWARD NRN LWR. THE GFS TAKES A MORE SRN TRACK AND WOULD
GIVE US MORE SNOW. HOWEVER...WE HAVE NOT HAD MANY CLIPPERS THAT
HAVE CROSSED THE CWA THIS YEAR AND SO WE/LL LEAN MORE TOWARD THE
FARTHER NORTH ECMWF. TEMPS WILL WARM FROM HIGHS IN THE MID TEENS
FRIDAY TO MID 30S BY MONDAY BEFORE COOLING OFF TUESDAY AFTER THE
CLIPPER DRAGS A COLD FRONT THROUGH.

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 715 PM EST TUE JAN 29 2013

ACTIVE WEATHER EXPECTED THE NEXT 24 HOURS ACROSS THE TAF SITES
WITH A COLD FRONT EXPECTED TO MOVE THROUGH THE AREA TONIGHT INTO
WEDNESDAY MORNING. THUNDERSTORMS WILL LIKELY AFFECT THE TAF SITES
BETWEEN 01Z AND 07Z ON THE LEADING EDGE OF A SHIELD OF
PRECIPITATION. STEADIER MODERATE RAINS ARE EXPECTED OVERNIGHT. IFR
AND MVFR CONDITIONS WILL BE COMMON THIS EVENING...TRENDING TOWARD
MORE WIDESPREAD IFR LATER TONIGHT INTO WEDNESDAY MORNING. THE IFR
CONDITIONS WILL LIFT BACK TO MVFR TOMORROW AFTERNOON AS THE COLD
FRONT PRESSES EAST. SOME SNOW WILL BEGIN TO MIX BACK IN TOWARD
KMKG DURING THE AFTERNOON AND TOWARD KGRR TOWARD EVENING.

.MARINE...
ISSUED AT 348 PM EST TUE JAN 29 2013

WILL HOIST A SMALL CRAFT ADVISORY FOR TONIGHT THROUGH THURSDAY
MORNING. THIS MAY HAVE TO BE UPGRADED TO A GALE WARNING FOR
WEDNESDAY LATER ON...BUT FOR NOW IT APPEARED MARGINAL ENOUGH TO
JUST GO WITH A SCA THROUGH THE PERIOD.

.HYDROLOGY...
ISSUED AT 957 PM EST TUE JAN 29 2013

HAVE ISSUED A FLOOD WARNING FOR THE LAKESHORE COUNTIES AS WELL AS
LAKE AND NEWAYGO COUNTY. AREAS THAT RECEIVED SUBSTANTIAL LAKE
EFFECT SNOW IN THE LAST WEEK OR SO HAVE SEEN A RAPID SNOW MELT
THAT HAS OCCURRED OVER FROZEN GROUND. THEREFORE...SNOW MELT WATER
AND RAINFALL IS GOING INTO RUNOFF AS OPPOSED TO INFILTRATING INTO
THE GROUND. RAINFALL TOTALS HAVE BEEN IMPRESSIVE SINCE LAST
NIGHT...WITH MUSKEGON SEEING OVER 2.25 INCHES OF RAIN NOW. THE
COMBINATION SNOW MELT WATER...RAINFALL OF THE LAST 24 HOURS AND
ADDITIONAL RAINFALL COMING UP TONIGHT HAS PROMPTED THE AREAL FLOOD
WARNING. DROPPED THE FLOOD WATCH IN THESE COUNTIES GIVEN THE
WARNING. THE FLOOD WATCH CONTINUES FOR THE REMAINDER OF THE AREA.
THE EXPECTATIONS IN THE WARNING AREA ARE THAT WE WILL SEE SMALLER
STREAMS AND RIVERS SPILL OUR OF THERE BANKS...PONDING OF WATER IN
LOW SPOTS OF ROADWAYS AND FLOODING OF CULVERTS...DITCHES AND FIELDS.
A SATELLITE PRECIPITATION ESTIMATE (SPENES) WAS RECENTLY ISSUED
ADVISING OF THE POTENTIAL OF ANOTHER 1-2 INCHES OF RAINFALL ACROSS
OUR AREA THROUGH 400 AM. WE WILL BE MONITORING THE COUNTIES TO THE
EAST OF THE WARNING AREA...BUT CONCERNS ARE NOT AS HIGH THERE AS
THE SNOW PACK WAS MINIMAL.

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...FLOOD WATCH THROUGH WEDNESDAY AFTERNOON FOR MIZ039-040-045-046-
051-052-057>059-065>067-072>074.

LM...SMALL CRAFT ADVISORY FROM 1 AM WEDNESDAY TO 7 AM EST THURSDAY
FOR LMZ844>849.

UPDATE...LAURENS
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...93
AVIATION...DUKE
HYDROLOGY...DUKE
MARINE...OSTUNO

AREA FORECAST DISCUSSION

NWS GRAND RAPIDS MI

818 PM EST TUE JAN 29 2013

.SYNOPSIS...
ISSUED AT 348 PM EST TUE JAN 29 2013

.UPDATE...
ISSUED AT 817 PM EST TUE JAN 29 2013

.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 348 PM EST TUE JAN 29 2013

.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 348 PM EST TUE JAN 29 2013

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 715 PM EST TUE JAN 29 2013

.MARINE...
ISSUED AT 348 PM EST TUE JAN 29 2013

.HYDROLOGY...
ISSUED AT 348 PM EST TUE JAN 29 2013

SCOTTVILLE ON THE PERE MARQUETTE IS FORECAST TO FLOOD...BUT OTHER
RIVER POINTS ARE CURRENTLY EXPECTED TO STAY BELOW FLOOD STAGE.
WILL HAVE TO WATCH THE PROGRESSION OF RAIN AND SNOW MELT THIS
EVENING AND SOME OTHER SITES MAY BE ADDED TO FLOOD WARNINGS AT
SOME POINT TONIGHT.

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...FLOOD WATCH THROUGH WEDNESDAY AFTERNOON FOR MIZ037>040-043>046-
050>052-056>059-064>067-071>074.

LM...SMALL CRAFT ADVISORY FROM 1 AM WEDNESDAY TO 7 AM EST THURSDAY
FOR LMZ844>849.

UPDATE...LAURENS
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...93
AVIATION...DUKE
HYDROLOGY...OSTUNO
MARINE...OSTUNO

AREA FORECAST DISCUSSION

NWS GRAND RAPIDS MI

715 PM EST TUE JAN 29 2013

.SYNOPSIS...
ISSUED AT 348 PM EST TUE JAN 29 2013

.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 348 PM EST TUE JAN 29 2013

.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 348 PM EST TUE JAN 29 2013

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 715 PM EST TUE JAN 29 2013

.MARINE...
ISSUED AT 348 PM EST TUE JAN 29 2013

.HYDROLOGY...
ISSUED AT 348 PM EST TUE JAN 29 2013

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...FLOOD WATCH THROUGH WEDNESDAY AFTERNOON FOR MIZ037>040-043>046-
050>052-056>059-064>067-071>074.

LM...SMALL CRAFT ADVISORY FROM 1 AM WEDNESDAY TO 7 AM EST THURSDAY
FOR LMZ844>849.

UPDATE...93
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...93
AVIATION...DUKE
HYDROLOGY...OSTUNO
MARINE...OSTUNO

AREA FORECAST DISCUSSION

NWS GRAND RAPIDS MI

607 PM EST TUE JAN 29 2013

.SYNOPSIS...
ISSUED AT 348 PM EST TUE JAN 29 2013

.UPDATE...
ISSUED AT 606 PM EST TUE JAN 29 2013

SENDING OUT A QUICK UPDATE TO ADD THUNDER TO GRIDS THIS EVENING.

.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 348 PM EST TUE JAN 29 2013

.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 348 PM EST TUE JAN 29 2013

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1252 PM EST TUE JAN 29 2013

WIDESPREAD IFR/LIFR CONDITIONS EXPECTED THROUGH THE PERIOD. WE/LL
SEE CONSIDERABLE RAIN TONIGHT AHEAD OF THE ARCTIC FRONT. TSRA ALSO
EXPECTED FROM AROUND SUNSET THROUGH MUCH OF THE OVERNIGHT HOURS.
IT/S POSSIBLE THAT SNOW WILL MIX IN WITH THE RAIN AT KMKG MID TO
LATE MORNING WEDNESDAY.

.MARINE...
ISSUED AT 348 PM EST TUE JAN 29 2013

.HYDROLOGY...
ISSUED AT 348 PM EST TUE JAN 29 2013

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...FLOOD WATCH THROUGH WEDNESDAY AFTERNOON FOR MIZ037>040-043>046-
050>052-056>059-064>067-071>074.

LM...SMALL CRAFT ADVISORY FROM 1 AM WEDNESDAY TO 7 AM EST THURSDAY
FOR LMZ844>849.

UPDATE...93
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...93
AVIATION...93
HYDROLOGY...OSTUNO
MARINE...OSTUNO

AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

413 PM CST MON JAN 28 2013

.DISCUSSION...

FIRST THE HEADLINES. STARTING WITH THE HRRR/RUC THEN THE REST OF
THE 12Z RUNS...MODELS BEGAN TO SHIFT HEAVY SNOW BAND FOR TONIGHT
FARTHER NORTHWEST...KEEPING THE BULK OF THE SNOW NW OF THE MPX
CWA. MAY STILL GET A COUPLE INCHES OF SNOW IN THE FAR NW CORNERS
OF TODD...DOUGLAS...AND STEVENS COUNTIES...SO WITH THAT ALONG WITH
MATCHING UP WITH WHAT NEIGHBORS WERE DOING...ISSUED A WINTER
WEATHER ADVISORY FOR THOSE THREE COUNTIES. AT THE OTHER END OF THE
CWA HAVE A FREEZING RAIN ADVISORY FOR NE 3 COUNTIES IN WI. NOT
THRILLED WITH DOING THIS ADVISORY...BUT TO MATCH UP WITH
NEIGHBORING OFFICES...INCLUDED THESE COUNTIES IN A FREEZING RAIN
ADVY. EVERYWHERE ELSE...DENSE FOG IS LOOKING LIKE ALL BUT A
CERTAINTY FOR TONIGHT...SO A NEW DENSE FOG ADVISORY HAS BEEN
HOISTED.

UPPER WAVE RESPONSIBLE FOR ALL OF THIS HEADLINE FUN IS A DEEP
THROUGH THAT CAN BE SEEN ACROSS THE ERN ROCKIES THIS
AFTERNOON...AND WILL SLIDE ACROSS THE CENTER OF THE CONUS THROUGH
WEDNESDAY. AT THIS SFC...A 996 MB LOW AT 3 PM WAS CENTERED OVER
ERN CO. FAIRLY GOOD CONSENSUS AMONGST GUIDANCE ON THIS LOW MOVING
TO NEAR THE SE TIP OF MN BY TUESDAY MORNING...THEN OFF TO ERN LAKE
SUPERIOR BY THE TUE AFTERNOON. SEEING AN IMPRESSIVE WARM FRONT
MOVING NORTH ACROSS THE PLAINS WITH THIS LOW...WITH TEMPS IN THE
LOWER 70S AND DEWPS IN THE LOWER 50S UP TO ALMOST THE IA BORDER.

FOR THE WEATHER TONIGHT...LEANED MOST TOWARD THE 12Z NAM FOR
TIMING PRECIP IN AND ACROSS THE AREA AS THIS IS A GOOD
CONTINUATION OF WHAT THE RAP HAS BEEN SHOWING. RIGHT NOW...SEEING
IMPRESSIVE FGEN BAND SETTING UP ACROSS NE SODAK INTO NW MN...AND
LOOKING AT RAP H7-H6 FGEN FORECAST...SHOULD SEE AN INTENSE BAND OF
SNOW SET UP FROM NEAR ABERDEEN UP TO DETROIT LAKES. WITHIN THE
CENTER OF THE BAND SHOULD SEE A GOOD 4 TO 6 INCHES OF SNOW. FOR
THE MPX AREA...FAR NW CORNERS OF OUR FAR NW COUNTIES SHOULD GET IN
ON THE SRN FRINGE OF THIS BAND...WITH A COUPLE OF INCHES OF SNOW
BEING POSSIBLE. FOR SNOW POTENTIAL IN THE WEST...WILL HAVE TO WHAT
HAPPENS WITH A SECONDARY SHORT WAVE THAT SNEAKS UP WEST OF THE SFC
LOW LATE TONIGHT INTO TUESDAY MORNING. THE GEM WAS THE MOST
BULLISH WITH THIS WAVE...BRING A QUICK 2-3 INCHES OF SNOW TO WRN
MN. DID NOT PUT MUCH STOCK IN IT...BUT NOTICING THAT TOWARD THE
END OF RECENT RAP RUNS IT HAS BEEN SHOWING THIS SECONDARY BAND
SNEAKING IN AS WELL...SO WILL NEED TO WATCH THIS OVERNIGHT TO SEE
IF THE WINTER WEATHER ADVISORY NEEDS TO BE PULLED SOUTH.

OUTSIDE OF THE NW CWA...SOUNDINGS SHOW WHATEVER HAPPENING TONIGHT
TO BE DRIZZLE OR LIGHT RAIN...WITH ATMO ABOVE ABOUT H8 BEING DRY...
AND LITTLE OR NO SATURATION BEING SEEN IN THE DENDRITIC GROWTH
ZONE. SHOULD SEE DZ/RA RAPIDLY SPREAD NORTH AFTER 00Z AS STRONG
LOW LEVEL THETA-E ADVECTION WORKS IN. AT THE NOSE OF THE LLJ...THE
RAP IS EVEN INDICATING SOME THUNDER BEING POSSIBLE IN THE EAU AREA
AROUND MIDNIGHT AS BEST LIS DROP TO AROUND -1. 18Z HRRR
REFLECTIVITY FORECAST LOOKS CONVECTIVE IN THIS AREA AS WELL. OF
COURSE WITH ALL OF THIS PRECIP THE KEY WILL BE SFC TEMPS. THE
ENTIRE CWA CURRENTLY SITS BETWEEN 32 AND 36 AND WITH CONTINUED
SOUTHEAST FLOW THROUGH THE NIGHT...DO NOT EXPECT THESE TO CHANGE
MUCH...IN FACT...TEMPERATURES MAY CONTINUE TO RISE RIGHT THROUGH
THE NIGHT ACROSS THE SE CWA. BECAUSE OF THESE MILD
TEMPERATURES...WAS NOT TOO INCLINED TO ISSUE A FREEZING RAIN ADVY
WITH IT BEING QUESTIONABLE IF TEMPS FALL BELOW FREEZING. IN
ADDITION...WITH P-TYPE MAINLY BEING DZ...NOT EXPECTING MANY IMPACTS
WITH DZ AND TEMPS IN THE 30S WITH ALREADY WET SFCS IN PLACE DUE TO
MELTING TODAY. MAKE IT DRY WITH TEMPS IN THE 20S...AND IT WOULD BE
A DIFFERENT STORY...BUT THAT IS NOT WHAT WE ARE DEALING WITH.
WHERE THE HIGHEST POTENTIAL FOR MEANINGFUL FZRA EXISTS WOULD BE IN
THE FAR NE CWA...WHERE THERE WILL BE THE POTENTIAL FOR RAIN THIS
EVENING ON THE NOSE OF THE LLJ.

AS FOR THE FOG...THERE IS NOTHING BUT A SEA OF DENSE FOG FROM SRN
MN DOWN ACROSS IA AND ERN NEB. THIS WILL ADVECT RIGHT BACK NORTH
THIS EVENING...WITH WIDESPREAD FOG EXPECTED AGAIN...AS SEEN WITH
THE GRIDDED LAMP...HRRR...AND WRF-NMM. FOG SHOULD IMPROVE LATE
TONIGHT FROM WEST TO EAST AS AN INVERTED TROUGH/COLD FRONT WORKS
ACROSS MN. FOR SIMPLICITY SAKE...RAN THE FOG ADVY THROUGH 10 AM
TUESDAY MORNING EVERYWHERE...BUT CONDITIONS SHOULD IMPROVE
EARLIER THAN THAT IN WRN MN.

PRECIPITATION SHOULD MOSTLY COME TO AN END BY TUESDAY AFTERNOON
ACROSS THE AREA AS DRY ARCTIC HIGH BEGINS BUILDING IN. STILL SOME
DISAGREEMENT WITH PRECIP POTENTIAL TUESDAY NIGHT AS ANOTHER SFC
LOW RIPPLES NORTH ALONG THE FRONT FROM THE TULSA AREA UP TO MID
MICHIGAN. HUNG SOME CHANCE POPS BACK ACROSS ERN AREA TO ACCOUNT
FOR THE OFF CHANCE THAT SOME SNOW DEVELOPS WEST OF THE LOW. NOT ALL
THAT EXCITED ABOUT SNOW POTENTIAL ON THE BACK SIDE OF THIS SYSTEM
TUESDAY NIGHT INTO WEDNESDAY DUE TO THE FACT THAT UPPER FLOW WILL
BE NEARLY PARALLEL TO THE FRONTAL BOUNDARY. THIS WILL LIKELY KEEP
A COLD CONVEYOR BELT FROM DEVELOPING TO THE NORTH AND NORTHWEST OF
THE LOW AS IT WORKS UP ALONG THE FRONT...WITH MOST ACTIVITY STAYING
NEAR THE FRONT...AND NOT WORKING BACK TOWARD THE EAU AREA.

OF COURSE THE BIG STORY FOR WEDNESDAY THROUGH FRIDAY WILL BE THE
ARRIVAL OF ANOTHER SIGNIFICANT CHUNK OF ARCTIC AIR. TEMPERATURES
WILL BE NEARLY STEADY OR FALLING MUCH OF WEDNESDAY AFTERNOON...AND
BY WEDNESDAY NIGHT...THE COMBO OF TEMPS FALLING TO BELOW ZERO ON
15 TO 25 MPH NW WINDS WILL BRING BACK THE NEED FOR WIND CHILL
ADVISORIES FROM WEDNESDAY NIGHT RIGHT INTO FRIDAY MORNING.

AFTER FRIDAY...TEMPERATURES WILL MODERATE BACK CLOSER TO AND EVEN A
LITTLE ABOVE NORMAL BY THE END OF THE WEEKEND. STILL SEEING THE
POTENTIAL FOR A CLIPPER FRI NIGHT/SATURDAY ON THE ECMWF/GEM...WITH
A COUPLE OF INCHES OF SNOW BEING POSSIBLE ALONG AND NORTH OF I-94.

.AVIATION... /18Z TAF ISSUANCE/

STRATUS AND FOG WILL CONTINUE THROUGH MOST OF THE PERIOD. WILL
MAINTAIN IFR CONDITIONS THROUGH 18Z TUE. MAY SEE CONDITIONS IMPROVES
TO MVFR TUE AFTERNOON AS SURFACE LOW PULLS EAST AND COLDER AIR MOVES
IN. STILL LOOKS LIKE A PERIOD OF MIXED FREEZING RAIN/RAIN CHANGING
TO SNOW OVER THE AREA OVERNIGHT. BEST FORCING REMAINS OVER
NORTHWEST AREAS AND WILL CONTINUE TO MENTION FREEZING RAIN THIS
EVENING TRANSITIONING TO SNOW AFTER 04Z AT KAXN. REMAINDER OF THE
AREA WILL LIKELY SEE -FZDZ OR PLAIN -DZ AS SOUNDINGS NOT SHOWING A
REAL DEEP MOIST LAYER...GENERALLY LESS THAN 6K FEET. DEEPER MOISTURE
MAY WORK OVER THE FAR EASTERN AREAS LATER TONIGHT AS THE SURFACE LOW
DEVELOPS TO THE SOUTHEAST. SURFACE WINDS BECOMING MORE SOUTHEAST IN
THE WAKE OF THE SURFACE HIGH AND AHEAD OF FRONT OVER THE EASTERN
DAKOTAS. SHOULD GRADUALLY TURN MORE NORTH/NORTHWEST WITH FROPA
DURING THE PERIOD. WILL LIKELY INCREASE TO 10-15 KNOTS BY LATE
TUESDAY MORNING OVER WESTERN AREAS.

/OUTLOOK FOR KMSP/

TUE NGT...MVFR CIGS WITH FLURRIES. NW WIND 10-15 KTS.
WED...MVFR CIGS WITH FLURRIES. NW WIND 15 TO 25 KTS.
THU...MVFR CIGS WITH FLURRIES. NW WIND 10 TO 15 KTS.

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...DENSE FOG ADVISORY UNTIL 9 AM CST TUESDAY FOR ANOKA-BENTON-BLUE
EARTH-BROWN-CARVER-CHIPPEWA-CHISAGO-DAKOTA-FARIBAULT-
FREEBORN-GOODHUE-HENNEPIN-ISANTI-KANABEC-KANDIYOHI-LAC QUI
PARLE-LE SUEUR-MARTIN-MCLEOD-MEEKER-MILLE LACS-MORRISON-
NICOLLET-POPE-RAMSEY-REDWOOD-RENVILLE-RICE-SCOTT-SHERBURNE-
SIBLEY-STEARNS-STEELE-SWIFT-WASECA-WASHINGTON-WATONWAN-
WRIGHT-YELLOW MEDICINE.

WINTER WEATHER ADVISORY UNTIL 6 AM CST TUESDAY FOR DOUGLAS-
STEVENS-TODD.

WI...DENSE FOG ADVISORY UNTIL 9 AM CST TUESDAY FOR DUNN-EAU CLAIRE-
PEPIN-PIERCE-POLK-ST. CROIX.

FREEZING RAIN ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM CST TUESDAY
FOR BARRON-CHIPPEWA-RUSK.

MPG/DWE

AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

206 AM CST MON JAN 28 2013

.UPDATE...

CANCELLED THE WINTER WX ADVISORY ACROSS WEST CENTRAL THROUGH SOUTH
CENTRAL MN AND REPLACED IT WITH A DENSE FOG ADVISORY. MAY HAVE TO
INCLUDE MORE OF THE CWA IF CONDITIONS WORSEN IN THE WAKE OF THE
LIGHT PRECIPITATION.

.DISCUSSION... /ISSUED 413 PM CST SUN JAN 27 2013

QUITE THE INTERESTING SYSTEM UNFOLDING ACROSS THE AREA TODAY WITH
INTENSE BAND OF SNOW WORKING ACROSS THE AREA THIS AFTERNOON WITHIN
A STRONG ZONE OF FGEN IN THE H7-H6 LAYER. AS THIS STRONGER AND
MORE PERSISTENT LIFT MOVED NORTH...THE AS ADVERTISED COLLAPSING OF
THE WARM NOSE BACK BELOW FREEZING ALLOWED THE EARLY INITIAL PUSH
OF FZRA/PL TO QUICKLY TRANSITION TO SNOW...AND QUITE THE
IMPRESSIVE SNOW IT HAS BEEN. WITHIN THE MAIN BAND OF SNOW...RATES
OF 1-2 INCHES PER HOUR HAVE BEEN QUITE COMMON. HERE AT THE OFFICE
IN CHANHASSEN...WE GOT ABOUT 2.5 INCHES OF BETWEEN ABOUT 130 AND
330. THAT WOULD BE MORE SNOW IN 2 HOURS THAN WE HAVE SEEN IN THE
REST OF THE MONTH COMBINED!

THIS BAND OF SNOW WILL BE QUICKLY MOVING EAST WITH THE FGEN...WITH
THE RAP SHOWING THE HEAVY SNOW SHOULD BE ALL BUT DONE IN THE TWIN
CITIES BY 00Z...WITH IT NOT LASTING MUCH PAST 3Z IN THE LADYSMITH
AREA. CURRENT GRIDS MAY NOT BE FAST ENOUGH IN CLEARING PRECIP OUT
THIS EVENING...BUT THAT CAN BE UPDATED THROUGH THE EVENING. WHAT
WILL BE TRICKY THOUGH...IS THAT AS THE MAIN PRECIP BATCH MOVES
THROUGH...HAVE SEEN EXTENSIVE DZ/FG REPORTS ACROSS ERN NEB AND IA
THAT WILL BE MOVING UP HERE THIS EVENING AND DO EXPECT A 2-4 HR
WINDOW OF FZDZ BEHIND THE MAIN PRECIP BEFORE WE ARE LEFT WITH WHAT
LOOKS TO BE A RATHER FOGGY NIGHT...WITH A DENSE FOG ADVY POSSIBLY
IN THE BOOKS...THOUGH WILL WAIT UNTIL WINTER WEATHER HEADLINES ARE
PULLED DOWN BEFORE ISSUING ANY DENSE FOG ADVISORIES. AS FOR THOSE
WINTER WEATHER HEADLINES...ONLY CHANGE WAS TO TRIM A FEW COUNTIES
OFF THE ADVY ON THE NW END WHERE PRECIP FAILED TO REACH AND MNDOT
CONTINUES TO ADVERTISE GOOD TRAVEL CONDITIONS. DOUBT WE WILL HIT
WINTER STORM WARNING CRITERIA FOR ANY ONE SPECIFIC TYPE OF
PRECIPITATION /0.25 INCH OF FZRA AND 6 INCHES OF SNOW/...BUT THE
COMBO OF A TENTH OF AN INCH OF FZRA BEING TOPPED WITH 3 TO 5
INCHES OF SNOW WARRANTS KEEPING THE WARNING GOING...THOUGH WOULD
SUSPECT IT CAN BE PULLED BEFORE 6Z.

WILL GET A BREAK IN THE PRECIP MOST OF THE DAY MONDAY...BEFORE THE
MAIN TROUGH CURRENTLY ACROSS THE ROCKIES BEGINS PROGRESSING ACROSS
THE PLAINS. WHAT WILL MAKE THIS PRECIP EVENT DIFFICULT FROM THE
P-TYPE PERSPECTIVE IS THAT AS TODAYS PRECIP MOVES OUT...THE WARM
NOSE WILL MOVE BACK IN...WITH ANOTHER MELTING LAYER IN PLACE
MONDAY AFTERNOON AS THIS NEXT SYSTEM MOVES IN. MAIN SFC LOW IS
FORECAST TO GO FROM NW KS MONDAY AFTERNOON TO THE U.P. OF MICH BY
TUESDAY AFTERNOON. ALL MODELS SHOWING TWO BATCHES OF PRECIP WITH
THIS SYSTEM. LLJ WARM SECTOR PRECIP LOOKS TO STAY WELL SE OF THE
AREA...WHILE ANOTHER INTENSE BAND OF FGEN INDUCED SNOW MOVES
ACROSS WRN INTO NE MN. WITH THIS SIGNAL...UPPED POPS TO THE
CATEGORICAL RANGE IN THE NW CWA MONDAY NIGHT...WITH 2-3 INCHES OF
SNOW UP IN THE MORRIS/ALEX AREA. CONFIDENCE ON PRECIP OCCURRENCE
ACROSS THE REST OF THE AREA IS A BIT LOWER AS THESE TWO BATCHES OF
PRECIP SPLIT THE AREA...BUT WHATEVER HAPPENS MONDAY NIGHT WITH
PRECIP IN THE ERN 2/3RDS OF THE CWA...FORECAST SOUNDINGS AGAIN SAY
THE P-TYPE WILL BE RA OR FZRA DEPENDING ON THE SFC TEMP.

AFTER NEARLY STEADY TEMPERATURES TODAY THROUGH TUESDAY...THE
ENCROACHMENT OF ANOTHER ARCTIC HIGH FOR THE END OF THE WEEK WILL
LEAD TO A SIGNIFICANT COOL DOWN STARTING TUESDAY NIGHT. WILL SEE
STRONG CAA ALL DAY WEDNESDAY RIGHT THROUGH WEDNESDAY NIGHT AS HIGH
PRESSURE GOES FROM THE DAKOTAS OVER TO THE KANSAS CITY AREA BY
FRIDAY MORNING. WILL SEE ANOTHER HEALTHY SURGE OF COLD BEHIND THIS
SYSTEM...WITH H85 TEMPS BY THURSDAY AGAIN BACK BETWEEN 25 C AND
30 C BELOW ZERO. THIS WILL GIVE MUCH OF THE MN CWA ANOTHER SHOT AT
SEEING SUB ZERO HIGHS THURSDAY AFTERNOON.

FOR FRIDAY THROUGH THE WEEKEND...A MODERATION IN TEMPERATURES IS
EXPECTED AS A CLIPPER SLIDES ACROSS NRN MN AND WI FRI
NIGHT/SATURDAY. MAY SEE A QUICK 1-2 INCHES OF SNOW OUT OF THIS
WITH CURRENT INDICATIONS BEING THAT THE BEST CHANCE FOR
ACCUMULATING SNOW WILL BE NORTH OF I-94.

.AVIATION... /06Z TAF ISSUANCE/

NOT MUCH PRECIP REMAINING...BUT FOG WILL BE A CONCERN COME MORNING
AT MOST OF THE TAF SITES...ESPECIALLY THOSE IN MN. DENSE FOG WITH
1/4SM OR LESS HAS BEEN SLOWLY ADVECTING EASTWARD OUT OF THE
DAKOTAS. KAXN/KRWF AND EVEN KSTC SHOULD SEE LIFR VIS BY
SUNRISE...HAVE ALSO INCLUDED IFR FOG IN EASTERN MN AND WESTERN
WI...BUT DIDN`T GO 1/4SM YET. WINTRY MIX CHANGING OVER TO SNOW
EXPECTED TO FROM WEST TO EAST ACROSS AREA LATE THIS AFTERNOON INTO
THE EVENING. REGARDLESS...SHOULD BE IFR ALL DAY AND NIGHT.

KMSP...

STILL POTENTIAL FOR 1/4SM DENSE FOG AT SOME POINT LATE IN THE
MORNING...BUT PLAYED IT A LITTLE CONSERVATIVE AT THE AIRPORT FOR
NOW. HOWEVER...HIGH CONFIDENCE IN IFR ALL DAY...BUT THERE
SHOULDN`T BE ANY NEW PRECIP UNTIL THIS EVENING. PRECIP COULD
ARRIVE AS EARLY AS THE LAST HALF OF THE EVENING COMMUTE...BUT MORE
LIKELY WILL HOLD OFF UNTIL THE LATE EVENING AND COME IN AS A
WINTRY MIX BEFORE CHANGING OVER TO SNOW LATE TONIGHT.

/OUTLOOK FOR KMSP/

TUE...MVFR/IFR CONDITIONS IN THE MORNING...MVFR CIGS BY AFTERNOON.
CHC -SN IN THE MORNING. NW WIND 5-10KT.
WED...MVFR CIGS. NW WIND 15G25KT.

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...DENSE FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR BLUE EARTH-
BROWN-CHIPPEWA-FARIBAULT-FREEBORN-GOODHUE-KANDIYOHI-LAC QUI
PARLE-LE SUEUR-MARTIN-MCLEOD-MEEKER-NICOLLET-POPE-REDWOOD-
RENVILLE-RICE-SIBLEY-STEELE-STEVENS-SWIFT-WASECA-WATONWAN-
YELLOW MEDICINE.

WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
ANOKA-BENTON-CARVER-CHISAGO-DAKOTA-DOUGLAS-HENNEPIN-ISANTI-
KANABEC-MILLE LACS-MORRISON-RAMSEY-SCOTT-SHERBURNE-STEARNS-
TODD-WASHINGTON-WRIGHT.

WI...WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
BARRON-CHIPPEWA-DUNN-EAU CLAIRE-PEPIN-PIERCE-POLK-RUSK-ST.
CROIX.

RAH/MPG/CLF

AREA FORECAST DISCUSSION...UPDATED

NWS TWIN CITIES/CHANHASSEN MN

1225 AM CST MON JAN 28 2013

.UPDATE...

UPDATED FOR THE 06Z AVIATION DISCUSSION BELOW.

.DISCUSSION...

.AVIATION.../06Z TAF ISSUANCE/

KMSP...

/OUTLOOK FOR KMSP/

TUE...MVFR/IFR CONDITIONS IN THE MORNING...MVFR CIGS BY AFTERNOON.
CHC -SN IN THE MORNING. NW WIND 5-10KT.
WED...MVFR CIGS. NW WIND 15G25KT.

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

WI...WINTER WEATHER ADVISORY UNTIL 6 AM CST MONDAY FOR BARRON-
CHIPPEWA-DUNN-EAU CLAIRE-PEPIN-PIERCE-POLK-RUSK-ST. CROIX.

MPG/CLF

AREA FORECAST DISCUSSION

NWS KANSAS CITY/PLEASANT HILL MO

1229 PM CST Mon Jan 28 2013

.UPDATE...
/1216 PM CST Mon Jan 28 2013/

Warm front has begun to lift across the forecast region, which has
rapidly cleared skies across the southern 3/4 of the forecast area.
Clouds across southern Missouri may move back in, but they will be
far more scattered in nature, so have gone ahead and upped
temperatures for areas along and south of the Missouri River. Have
also bumped temperatures along the Iowa border as the fog is
disipating and clouds are thinning out, though did not warm them as
much.

Cutter

.DISCUSSION...

Unseasonable warmth and copious moisture has overspread the region
this morning. This will set the stage for some potentially active
weather tonight and Tuesday as a strong system interacts with this
warm airmass.

For today, frontal boundary is settling southward to near a Kansas
City to Kirksville line where it will begin to stall through the
morning. Cold air behind the front and copious low-level moisture
have led to widespread dense fog over the northwest forecast area
where a dense fog advisory has been issued through noon. How soon the
fog will lift is still in question, so decided to play it
liberally and take the advisory as late as noon to give the
airmass plenty of time to start mixing as the frontal boundary lifts
north through the day.

Temperatures today could approach or exceed record territory for
Kansas City (record high is 65 set in 1917), but a lot depends on
when or if the widespread stratus deck in place can start to mix out.
This deck looks quite thick and latest NAM and RAP models indicate it
could hang around all day long for most of the forecast area. See no
reason to go against these models, so kept skies cloudy through the
day and as a result nudged temperatures down a few degrees area-wide.
Still, with the southern half of the KC metro still sitting at 61
degrees at 3 AM and parts of northern Oklahoma in the middle 60s,
simple warm air advection alone should be able to send areas south of
the Highway 36 corridor into the middle and upper 60s this afternoon
despite widespread cloud cover. Areas further north are likely to see
fog, low clouds and drizzle stick around for much of the afternoon
until the front lifts through, so took temperatures down several
degrees for these areas.

Forecast gets interesting tonight and Tuesday as a strong upper
trough deepens across the Central Plains and moves into this
unseasonably warm airmass. This is likely to result in widespread
showers and thunderstorms developing along a cold front that will
move through the forecast area early Tuesday. However, there could be
some scattered convection developing ahead of the front as early as
midnight tonight over parts of the forecast area as hinted at by
nearly every model. With the front and upper trough still west of the
area tonight, large-scale ascent will be quite limited with forcing
mainly coming from broad and weak low-level convergence and
isentropic ascent. However, models are suggesting weak yet almost
uninhibited surface-based instability developing across the western
and southern forecast area overnight. This combined with very high
low-level shear and very low LCL heights could favor a damaging wind
and/or tornado risk with any storms that do develop. Will keep an
eye on this overnight, but for now expect the overall severe threat
to stay low until the arrival of the cold front can provide
persistent forcing for any organized convection given the high
shear/low instby combo.

Most models have slowed down the arrival of Tuesday`s cold front, now
poised to enter northwest Missouri around 12Z, reaching the I-35
corridor around 18Z and the southeast CWA border around 00Z. Expect
one or more lines of convection to develop near and ahead of the
front which could develop as early as 12Z over the northwest CWA
Tuesday morning. Instability will remain rather weak (<1000 J/kg)
but continued strong low-level shear will favor thin convective lines
capable of small bows and possible low-level rotation and tornadoes
as far west as I-35 Tuesday morning, moving into central MO through
the afternoon.

Finally, as the front pushes into eastern MO Tuesday night and
Wednesday, a few models are suggesting a weak wave riding up the
boundary in response to a vort max rounding the base of the large
upper trough. Such a feature could produce light rain/snow across the
eastern forecast area with the potential for accumulating snow
looking low at this time.

Hawblitzel

Medium Range (Thursday through Monday):

Little change in reasoning to current extended forecast period with
this issuance. Another shot of cold air is projected to enter the
region on Thursday as an upper wave on the backside of the eastern
CONUS longwave trough dives into the Ohio Valley. The cold air will
remain in place through Friday as surface high pressure moves across
the area. Temperatures will be below normal Thursday into Friday,
with highs on Thursday only reaching the 20s to lower 30s. The
coldest air of the forecast period is anticipated on Thursday night
into Friday morning upon clear skies and light winds, with low
temperatures in the single digits and teens. Surface high pressure
moves off to the east on Friday night with northwest flow aloft
persisting through the remainder of the forecast. A gradual
moderation of temperatures and dry weather is anticipated during
this period. The overall pattern suggested by operational guidance
shows an upper ridge developing over the western CONUS by the end of
the weekend, but confidence is not particularly high on the details
of the evolution of large-scale features and likewise temperatures
by the end of the period.

Blair

.AVIATION...

For the 18Z TAFs...VFR conditions are rapidly spread north across the
terminals as we close in on 18Z. Gusty south winds will spread into
the sites as a result this afternoon. Low clouds, MVFR, will then
move back in this evening. Pressure gradient will stay up through the
overnight hours, so surface winds are not expected to decouple and
will therefore stay above 12 knots all night long. Additionally, with
the strong surface winds comes a strong low level jet, so have also
included wind shear, though it will shift east of the terminals early
Tuesday morning.

Lastly, included some VCTS and PROB30`s for thunderstorms Tuesday
morning. Much of the stormy activity is expected to be east of the
terminals, but some scattered activity might develop far enough west
to impact them in the morning. A front progressing through the
Central Plains will shove the thunderstorm activity farther east
during the afternoon hours.

Cutter

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

WFO EAX

AREA FORECAST DISCUSSION

NWS KANSAS CITY/PLEASANT HILL MO

1152 AM CST Mon Jan 28 2013

...UPDATED AVIATION DISCUSSION...

.DISCUSSION...

Hawblitzel

Medium Range (Thursday through Monday):

Blair

.AVIATION...

Cutter

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

WFO EAX

AREA FORECAST DISCUSSION

NWS KANSAS CITY/PLEASANT HILL MO

554 AM CST Mon Jan 28 2013

...UPDATED AVIATION DISCUSSION...

.DISCUSSION...

Hawblitzel

Medium Range (Thursday through Monday):

Blair

.AVIATION...

For the 12Z TAFs...weak front has nudged south to near an MKC-IRK
line. This front will stall near this position then return north as a
warm front through the morning. Widespread dense fog has settled in
north of this boundary, with a well-defined southern edge about 60 nm
north of the surface boundary from near SLN to 25 nm N of STJ to BRL.
Satellite trends show that this fog has ceased moving southward and
should begin retreating northward through the morning, leaving STJ
and KC terminals unaffected.

Main concern for the STJ/MKC/MCI TAF sites will be stratus deck which
is currently MVFR (small band of DZ and very low cigs near MCI is
dissipating). Model soundings continue to show these clouds lowering
into IFR for much of the morning and then lifting back into MVFR late
in the day. Confidence on this happening is not terribly high, but
IFR cigs do exist further southwest across cntrl/eastern KS so will
go ahead and bring these into the terminals later this morning.
If/when these low cigs lift back into MVFR is quite questionable but
best bet is that daytime heating brings cigs back to MVFR by
afternoon.

Could see some scattered showers or convection develop overnight but
better chances are after 12Z Tues. Not enough confidence to introduce
TS/CB at this time. Considered LLWS overnight with strong 50-kt winds
at 2 kft, but low level winds look to gradually increase with height
versus a sharp increase, so kept it out for now.

Hawblitzel

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...DENSE FOG ADVISORY until Noon CST today FOR MOZ001>008-011.

KS...NONE.
&&

WFO EAX

AREA FORECAST DISCUSSION

NWS KANSAS CITY/PLEASANT HILL MO

352 AM CST Mon Jan 28 2013

.DISCUSSION...

Hawblitzel

Medium Range (Thursday through Monday):

Blair

.AVIATION...

For the 06Z TAFs: MVFR stratus continues to expand throughout eastern
Kansas and northern Missouri tonight and will remain entrenched
through at least mid-day Monday. Models in general have backed off on
the development of very low LIFR visibility and ceilings around
daybreak. However, still feel the development of IFR ceilings will be
likely after 09z as a frontal boundary drops into northern Missouri.

Expecting stratus to remain in place along and north of the
aforementioned front through early afternoon before erosion rapidly
begins in southeastern Kansas and spreads northeast. Ceilings should
quickly scatter or lift by 21Z as warm air pours northward. VFR
conditions should prevail Monday evening in most locations, as a warm
front lifts well into Iowa. Low confidence at this stage and haven`t
included in current TAF, but scattered showers or even thunder may
develop Monday evening.

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...DENSE FOG ADVISORY until Noon CST today FOR MOZ001>003-011.

KS...NONE.
&&

WFO EAX

AREA FORECAST DISCUSSION

NWS HASTINGS NE

728 PM CST TUE JAN 29 2013

.UPDATE...EVENING UPPER AIR ANALYSIS INDICATES A LONGWAVE TROUGH
OVER THE CENTRAL CONUS...WITH RIDGING OVER THE EAST AND WEST. MID
AND UPPER LEVEL JET ENERGY EXTENDS SOUTH/SOUTHEAST FROM SOUTHWEST
CANADA INTO THE FOUR CORNERS REGION...AND THEN EAST INTO THE
SOUTHERN PLAINS BEFORE TURNING NORTHEAST ACROSS PORTIONS OF THE
CENTRAL PLAINS AND MISSISSIPPI VALLEY. ALTHOUGH THE PRIMARY AXIS
OF THIS JET ENERGY REMAIN JUST EAST/SOUTHEAST OF OUR CWA...RAP
DATA DOES SUGGEST WIND SPEEDS GENERALLY RANGING FROM 50-100KTS IN
EXISTENCE FROM WEST TO EAST ACROSS OUR CWA AROUND 400MB...WITH THE
STRONGEST WIND RESIDING ACROSS OUR EAST. WATER VAPOR IMAGERY SHOWS
INCREASED VALUES OF MID LEVEL MOISTURE EXTENDING FROM EASTERN
TEXAS...NORTHEAST INTO THE MID MISSISSIPPI VALLEY...AND A MID
LEVEL DRY INTRUSION WORKING INTO THE CENTRAL PLAINS. AT THE
SURFACE A COLD FRONT IS NOTED EXTENDING FROM CENTRAL
MISSOURI...SOUTHWEST INTO PORTIONS OF KANSAS...OKLAHOMA AND TEXAS.
OUR CWA IS CURRENTLY ON THE BACK SIDE OF THIS FRONT WITH A
NORTHERLY LOW LEVEL WIND FIELD PREVAILING ACROSS THE AREA AS A
RESULT. RADAR DATA FROM KUEX INDICATES BANDED PRECIPITATION OVER
THE SOUTHEASTERN HALF OF OUR CWA...HOWEVER COMMUNICATION WITH
OBSERVERS HAVE YIELDED LITTLE MORE THAN TRACE REPORTS OF SNOWFALL
ACCUMULATION THIS EVENING...ALTHOUGH ACCUMULATION IS UNDOUBTEDLY
BEGINNING TO OCCUR ALONG AND EAST OF HIGHWAY 281 NOW.

GUIDANCE FROM THE NAM...OPERATIONAL GFS...EC AND SREF-MEAN ALL
SUGGEST PORTIONS OF THE LONGWAVE TROUGH NEAR OUR AREA WILL
STRENGTHEN INTO A SHORT WAVE FEATURE AS IT PUSHES OVER PORTIONS OF
NEBRASKA AND KANSAS...AND EVENTUALLY INTO IOWA AND MISSOURI
TONIGHT. AS MID LEVEL VORTICITY INCREASES WITH THE STRENGTHENING
MID LEVEL SHORT WAVE...SO WILL MID LEVEL DEFORMATION TO THE
WEST/NORTHWEST OF THE MID LEVEL SHORT WAVE AXIS...WITH THE PRIMARY
AXIS OF MID LEVEL DEFORMATION EXPECTED TO PERSIST FROM EASTERN
NEBRASKA...INTO PORTIONS OF SOUTH CENTRAL NEBRASKA AND NORTH
CENTRAL KANSAS THIS EVENING...AND THEN EAST INTO WESTERN IOWA AND
SOUTHEASTERN NEBRASKA BY 06Z TONIGHT. THIS AXIS OF DEFORMATION AND
RESULTANT MID LEVEL FRONTOGENESIS...PRIMARILY NEAR 700MB...WILL
CONTINUE TO PROVIDE BANDED PRECIPITATION ACROSS PORTIONS OF OUR
AREA THROUGH AT LEAST 06Z...WITH THE EAST/SOUTHEASTERN PORTIONS OF OUR
CWA STILL UNDER THE GUN TO RECEIVE A DECENT ROUND OF FRESH
SNOWFALL THIS EVENING. FORECAST CROSS SECTIONS ALSO INDICATE A
WEAK ZONE OF -EPV WILL PERIODICALLY EXIST JUST ABOVE THE MID LEVEL
FRONTOGENESIS THIS EVENING...WHICH INDICATES AT LEAST SOME SLANT-
WISE CONVECTION AND A POSSIBILITY FOR INCREASED PRECIPITATION
RATES.

THE CURRENT THINKING IS THAT THIS AREA OF BANDED PRECIPITATION
WILL CONTINUE SHIFTING EAST/NORTHEAST ALONG WITH THE PRIMARY AXIS
OF MID LEVEL FRONTOGENEIS THROUGH TONIGHT...WITH PRECIPITATION
RATES INCREASING AS THE AFOREMENTIONED MID LEVEL FRONTOGENESIS
ALSO INTENSIFIES ACROSS EAST/SOUTHEASTERN PORTIONS OF OUR CWA.
PRECIPITATION SHOULD THEN TAPER OFF ACROSS OUR CWA STARTING AROUND
06Z AS THE PRIMARY AXIS OF MID LEVEL FRONTOGENESIS ALSO MOVES EAST
OF OUR AREA. THIS IS A SOLUTION SUPPORTED BY QPF FIELDS FROM THE
NAM...OPERATIONAL GFS...EC...SREF-MEAN...RAP...HRRR...AND 4KM WRF-
NMM. EXACT LIQUID PRECIPITATION AMOUNTS VARY FROM MODEL TO
MODEL...BUT IN GENERAL THEY AVERAGE BETWEEN 0.1" AND 0.2" ACROSS
OUR SOUTHEAST. WITH LOWER TROPOSPHERIC TEMPERATURE EXPECTED TO
AVERAGE IN THE UPPER 20S TO NEAR 30 DEGREES F...WILL GO AHEAD AND
ASSUME AN AVERAGE SNOW-WATER RATIO OF 12:1...WHICH PRESENTS
SNOWFALL ACCUMULATION GENERALLY IN THE 1-2.5" RANGE. GIVEN THE
POTENTIAL FOR MODEST SLANT-WISE CONVECTION HOWEVER...WILL GO AHEAD
AND ADD ANOTHER INCH TO THE MODEL OUTPUT WHICH PROVIDES SNOWFALL
ACCUMULATION CLOSER TO THE 2-4" RANGE.

IN ADDITION TO THE SNOWFALL...LOW LEVEL PRESSURE RISES BEHIND THE
LOW LEVEL BAROCLINIC ZONE...CURRENTLY TO OUR SOUTH...ARE EXPECTED
TO INDUCE A STRENGTHENING LOW LEVEL PRESSURE GRADIENT TONIGHT.
GUIDANCE FROM THE MET AND MAV SUGGEST A SUSTAINED WIND AVERAGING
BETWEEN 15 AND 20KTS...WITH LOCALLY HIGHER GUSTS...WILL BE COMMON
ACROSS OUR CWA DURING THE SNOWFALL WHICH WILL CERTAINLY CREATE
SOME VISIBILITY RESTRICTION IN BLOWING SNOW.

OVERALL THE TIMING AND POSITION OF THE CURRENT WINTER WEATHER
ADVISORY ARE IN GREAT SHAPE...SO MADE NO CHANGES THERE. OUR
FORECAST SNOWFALL AMOUNTS DID SEEM A TOUCH ON THE HIGH SIDE BASED
ON THE LATEST MODEL OUTPUT...SO DID GO AHEAD AND DECREASE SNOWFALL
ACCUMULATION DOWN INTO THE 2-4" RANGE FOR THE ADVISORY AREA.
REMAINDER OF THE FORECAST REMAINS IN GREAT SHAPE WITH ONLY MINOR
CHANGES MADE TO HOURLY TEMPERATURE...WIND AND DEWPOINTS GRIDS TO
BETTER REFLECT CURRENT CONDITIONS.

.PREV DISCUSSION... /ISSUED 533 PM CST TUE JAN 29 2013/

AVIATION...00Z KGRI TAF. MVFR CEILINGS EXPECTED THROUGH THE FIRST
HALF OF THE TAF PERIOD WITH LIGHT SNOW ALSO EXPECTED TO PERSIST
THROUGH VERY EARLY WEDNESDAY MORNING. VISIBILITY RESTRICTION IN
BLOWING SNOW WILL ALSO BE POSSIBLE LATER TONIGHT AS THE NORTH
WIND INTENSIFIES. VFR CONDITIONS SHOULD BE RESTORED SHORTLY AFTER
SUNRISE WEDNESDAY.

PREV DISCUSSION... /ISSUED 358 PM CST TUE JAN 29 2013/

SHORT TERM...TONIGHT AND WEDNESDAY.

HIGHLY AMPLIFIED MEAN TROUGH IS HEADING EAST WITH THE AXIS CROSSING
INTO THE HIGH PLAINS. STRONG JET AHEAD OF THIS AXIS WITH STIFF
MID-LEVEL FRONTOGENETIC FORCING PREDICTED TO RAMP UP THIS EVENING.
THIS IS SUPPORTED BY THE NAM...HRRR...ECMWF...AND GFS...ALL PLACING
DECENT QPF AMOUNTS IN THE EAST/SOUTHEAST PART OF THE CWA AT THE VERY
LEAST.

THIS AGREEMENT AMONG MODELS HAS LED ME TO INCREASE CHANCES OF
PRECIPITATION EVEN MORE. SOUNDINGS INDICATE THAT THIS WILL BE A SNOW
EVENT AND HAVE GONE WITH ONLY SNOW AS THE PRECIPITATION TYPE...AS
OPPOSED TO MENTIONING RAIN AT ONSET. THE HRRR INDICATE4D QUITE A RAMP
UP IN QPF PRODUCTION BY EARLY AFTERNOON...WHICH PROMPTED ME TO GO
WITH AN ADVISORY FOR MOST OF OUR EASTERN CWA. I FELT INCLINED TO DO
THIS AS NORTH/NORTHWEST WIND WILL RAMP UP CONSIDERABLY TONIGHT AS
THE SURFACE PRESSURE GRADIENT INCREASES. I INCREASED WIND SPEEDS A
BIT MORE FROM THE PREVIOUS FORECAST FOR TONIGHT INTO WEDNESDAY. SNOW
SHOULD WIND DOWN FAIRLY QUICKLY AS THE TROUGH AXIS HEADS TO THE EAST
BY THE OVERNIGHT. LEFT THE SLIGHT CHANCE OF FLURRIES IN OUR
NORTHEAST FOR WEDNESDAY MORNING...BUT I DID NOTICE THE NAM PULLING
BACK A LITTLE ON STRATUS...WHICH USUALLY INDICATES A LACK OF FLURRY
POTENTIAL...BUT CLOSE ENOUGH FOR ME TO LEAVE IN FOR NOW. WIND SHOULD
REMAIN BELOW WIND ADVISORY CRITERIA FOR WEDNESDAY...ALTHOUGH OUR FAR
NORTH MAY FLIRT WITH IT...JUDGING BY PREDICTED MOMENTUM TRANSFER.
KEPT SKY COVER GENERALLY CLOUDY...ALTHOUGH THERE COULD BE SOME
BREAKS...ESPECIALLY IN THE SOUTH BY AFTERNOON. KEPT TEMPERATURES THE
SAME FOR TONIGHT AND WEDNESDAY FROM PREVIOUS FORECAST AS THEY LOOKED
LIKE THEY WERE RIGHT ON TARGET.

LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY. MAIN FORECAST CONCERN
IN THE EXTENDED WILL BE THE TEMPERATURES.

STARTING WED EVENING...THE BIG PICTURE SHOWS THE CENTRAL U.S. IN
NORTHWEST FLOW AS THE UPPER TROUGH IS SLATED TO BE MOVING INTO THE
MIDWEST WITH RIDGING MOVING ONTO THE PACIFIC NORTHWEST COAST. AS THE
WORK WEEK ROLLS ALONG IT APPEARS WE WILL PRETTY MUCH STAY IN THIS
TYPE OF FLOW WITH OVERALL RIDGING TO THE WEST AND TROUGHING EAST.

WILL MOST LIKELY HAVE A FEW CLIPPER LIKE WAVES SLIDE THROUGH OUR
REGION UNDER THIS TYPE OF PATTERN AND THE QUESTION IS WILL THEY
BRING ANY ADDITIONAL PRECIPITATION CHANCES. BASIC ANSWER IS NO
ALTHOUGH WE DO HAVE A CHANCE OF FLURRIES MENTIONED FOR WED NIGHT AND
THURSDAY IN THE CURRENT FORECAST AND WILL GO AHEAD AND KEEP THEM IN
GIVEN SUFFICIENT MOISTURE AND COLDER TEMPERATURES NOTED IN MODEL
FORECAST SOUNDINGS. OTHERWISE WILL LEAVE THE REST OF THE FORECAST
DRY ALTHOUGH SOME LIGHT PRECIPITATION NOT TOTALLY OUT OF THE
QUESTION FOR FRIDAY.

AS FAR AS TEMPERATURES GO...IT WILL REMAIN QUITE CHILLY WED NIGHT
INTO FRIDAY MORNING AS ADDITIONAL COLD AIR SLIDES DOWN FROM THE
NORTH...ALTHOUGH THE BITTER COLD AIR SHOULD REMAIN JUST NORTHEAST OF
THE CWA. STOUT NORTHWEST WINDS ARE ALSO EXPECTED AGAIN FOR THURSDAY
AFTERNOON AS WE SIT BETWEEN 1038 MB HIGH PRESSURE OVER MONTANA/NDAK
AND LOW PRESSURE ACROSS MISSOURI AND KANSAS. FRIDAY MORNING MIGHT
BE THE COLDEST DAY OF THE WEEK DEPENDING ON WHETHER HIGH PRESSURE
DROPS RIGHT OVER THE TOP OF US OR SLIDES A LITTLE TO THE EAST IN
WHICH CASE WE MIGHT HAVE A MORE CLOUD COVER AND LIGHT SOUTHERLY
FLOW.

GOING INTO THE WEEKEND HEIGHTS BEGIN TO RISE AS WESTERN RIDGE STARTS
TO MOVE EAST AND AT THIS POINT APPEARS BOTH SAT AND SUNDAY SHOULD BE
CLOSE TO 50 DEGREES. ANOTHER WEAK FRONT IS EXPECTED TO PUSH ACROSS
SUNDAY NIGHT OR MONDAY WITH HIGH TEMPERATURES FALLING A TAD BUT
STILL ABOVE SEASONAL LEVELS.

.GID WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL 1 AM CST WEDNESDAY FOR NEZ049-063-
064-076-077-086-087.

KS...WINTER WEATHER ADVISORY UNTIL 1 AM CST WEDNESDAY FOR KSZ007.

0728 PM UPDATE/AVIATION...BRYANT
SHORT TERM...HEINLEIN
LONG TERM...EWALD

AREA FORECAST DISCUSSION

NWS HASTINGS NE

533 PM CST TUE JAN 29 2013

.AVIATION...00Z KGRI TAF. MVFR CEILINGS EXPECTED THROUGH THE FIRST
HALF OF THE TAF PERIOD WITH LIGHT SNOW ALSO EXPECTED TO PERSIST
THROUGH VERY EARLY WEDNESDAY MORNING. VISIBILITY RESTRICTION IN
BLOWING SNOW WILL ALSO BE POSSIBLE LATER TONIGHT AS THE NORTH
WIND INTENSIFIES. VFR CONDITIONS SHOULD BE RESTORED SHORTLY AFTER
SUNRISE WEDNESDAY.

.PREV DISCUSSION... /ISSUED 358 PM CST TUE JAN 29 2013/

SHORT TERM...TONIGHT AND WEDNESDAY.

LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY. MAIN FORECAST CONCERN
IN THE EXTENDED WILL BE THE TEMPERATURES.

.GID WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL 1 AM CST WEDNESDAY FOR NEZ049-063-
064-076-077-086-087.

KS...WINTER WEATHER ADVISORY UNTIL 1 AM CST WEDNESDAY FOR KSZ007.

AVIATION...BRYANT
SHORT TERM...HEINLEIN
LONG TERM...EWALD

AREA FORECAST DISCUSSION...UPDATED

NWS NORTH PLATTE NE

1115 PM CST SUN JAN 27 2013

.UPDATE...

.AVIATION...
IT LOOKS LIKE THE FOG SHOULD SPREAD INTO KLBF BUT NOT MUCH FARTHER
WEST. NO FOG EXPECTED FOR KVTN. THE FOG IS VERY SHALLOW WITH THE
MOON VISIBLE SO BURN OFF SHOULD COMMENCE BY 15Z WITH VFR RAPIDLY
DEVELOPING. THE HIGH PLAINS COLD FRONT IS THROUGH KRAP AND SHOULD
CONTINUE MOVING SOUTH. BEST GUESS FOR IFR/MVFR WOULD BE 15Z ACROSS
NRN NEB AND MOVING VERY SLOWLY SOUTH THROUGHOUT THE AFTN.

WIDESPREAD IFR/MVFR IS EXPECTED IN SNOW AND LOW CIGS MONDAY NIGHT
AS AN UPPER LEVEL DISTURBANCE LIFTS NORTHEAST THROUGH THE ROCKIES
AND INTO THE CNTL/NRN PLAINS.

.PREV DISCUSSION... /ISSUED 1022 PM CST SUN JAN 27 2013/

UPDATE...

DISCUSSION...
SFC OBS AND SATELLITE SUGGEST DENSE FOG IS FILLING INTO HOLT AND
BOYD COUNTIES SO THIS AREA HAS BEEN ADDED TO THE DENSE FOG ADVISORY.

PREV DISCUSSION... /ISSUED 814 PM CST SUN JAN 27 2013/

UPDATE...

DISCUSSION...
DENSE FOG IS DEVELOPING ACROSS CUSTER...GARFIELD AND WHEELER
COUNTIES SO A DENSE FOG ADVISORY HAS BEEN ISSUED FOR THOSE AREAS.
ADDITIONAL COUNTIES WILL BE ADDED TO THE ADVISORY AS WARRANTED.

PREV DISCUSSION... /ISSUED 529 PM CST SUN JAN 27 2013/

UPDATE...

AVIATION...
A COLD FRONT NEAR KGCC WILL DROP SOUTH TO NEAR HIGHWAY 20
OVERNIGHT AND BECOME THE FOCUS FOR IFR CIGS MONDAY AFTERNOON. THE
FRONT COULD END UP FARTHER SOUTH...PERHAPS NEAR HIGHWAY 2 MONDAY
MORNING SO THE FCST ACROSS NRN NEB IS UNCERTAIN.

SOUTH...ALONG INTERSTATE 80 NORTH AND SOUTH TO HIGHWAY 2 AND
HIGHWAY 6...FOG APPEARS LIKELY TONIGHT. MOISTURE PROFILES IN THE
NAM AND RAP MODELS SUGGEST SHALLOW FOG...AND THE RAP SUGGESTS FOG
NEAR KVTN ADDING TO THE FCST UNCERTAINTY ACROSS NRN NEB TONIGHT.

PREV DISCUSSION... /ISSUED 355 PM CST SUN JAN 27 2013/

SYNOPSIS...

SURFACE LOW PRESSURE DOMINATING THE REGION THIS AFTERNOON. SKIES
HAVE TURNED MOSTLY SUNNY ACROSS WESTERN NEBRASKA WITH TEMPERATURES
IN THE LOWER/MID 50S. STRATUS AND AREAS OF FOG HANGING ON IN
CENTRAL AND EASTERN NEBRASKA WITH UPPER 30S TO MID 40S.

SHORT TERM...

TONIGHT THROUGH MONDAY NIGHT...RECENT RAINFALL FROM EARLY THIS
MORNING HAS LEFT THE GROUND DAMP. RAINFALL AMOUNTS RANGED FROM
0.05 TO 0.25 INCH. DENSE FOG WHICH DEVELOPED IN THE WAKE OF THE
RAIN THIS MORNING COULD AGAIN DEVELOP THIS EVENING A FEW HOURS
AFTER SUNSET. MODELS DO NOT INDICATE A STRONG SIGNAL FOR FOG.
HOWEVER DAMP AND COLD GROUND WITH SURFACE TEMPERATURES ABOVE
FREEZING THROUGH MUCH OF THE NIGHT WITH MAINLY CLEAR SKIES IS
OPTIMAL FOR RADIATION FOG. THUS...HAVE AREAS OF FOG SOUTHEASTERN
AREAS WITH PATCHY FOG NORTH CENTRAL 03Z TIL 15Z MONDAY. OVERNIGHT
LOWS ONLY FROM 26 TO 30 DEGREES.

ANOTHER MILD DAY FOR MOST AREAS MONDAY. APPROACH OF UPPER TROUGH
WILL INDUCE SURFACE CYCOLGENESIS FROM NORTHEAST COLORADO INTO
NORTHWEST KANSAS. AHEAD OF A COLD FRONT...AREAS ALONG AND SOUTH OF
AN OGALLALA THROUGH ONEILL LINE SHOULD WARM TO 50 DEGREES WITH
NEAR 60 POSSIBLE FAR SOUTHERN COUNTIES. TO THE NORTHWEST...HIGHS
TO REACH THE UPPER 30S TO UPPER 40S. AS LIFT FROM NORTHERN STREAM
THROUGH BEGINS DURING THE AFTERNOON...A CHANCE FOR RAIN ACROSS THE
NORTHWEST HALF. RAIN MAY MIX WITH SNOW FAR NORTHWEST BY LATE
AFTERNOON. FOR MONDAY NIGHT...MODELS REMAIN CONSISTENT BUT WEAKER WITH
SYNOPTIC SCALE FORCING. THE EXCEPTION IS THE NAM MODEL WHICH
INDICATES FAIRLY STRONG FRONTOGENESIS CENTERED AROUND 700MB. THIS
MAY LEAD TO HEAVIER SNOW BANDS OF 1 TO 2 INCHES. OVERALL SNOWFALL
AMOUNTS LOOK TO RANGE FROM AN INCH OR LESS.

TUESDAY AND WEDNESDAY...UPPER SYSTEM WILL TRANSLATE SOUTHEASTWARD
AND WEAKEN TUESDAY. ONLY A SLIGHT CHANCE FOR LIGHT SNOW IN THE
MORNING. COLDER AREA WIDE 35 TO 40 DEGREES. SURGE OF ARCTIC AIR
TUESDAY NIGHT TO BRING A SLIGHT CHANCE FOR LIGHT SNOW AND FLURRIES
TO THE NORTH CENTRAL. LOW TO BE 10 TO 15 ABOVE AND HIGHS WEDNESDAY
FROM 18 AT ONEILL TO 35 AT IMPERIAL.

LONG TERM...

AMPLIFIED NORTHWEST FLOW WITH A REINFORCING SHOT OF ARCTIC AIR
WILL BRING A SLIGHTLY COLDER DAY THURSDAY. HIGHS FROM 13 AT ONEILL
TO 35 AT IMPERIAL. ALSO A SLIGHT CHANCE FOR SNOW ACROSS WESTERN
AREAS. UPPER FLOW WILL TRANSITION TO A MORE ZONAL FLOW ALOFT WITH
TEMPERATURES WARMING INTO THE 40S TO AROUND 50 FOR THE WEEKEND.
DRY CONDITIONS EXPECTED FRIDAY THROUGH SUNDAY.

AVIATION...

SOME QUESTION ON THE FOG POTENTIAL FOR TONIGHT ACROSS CENTRAL AND
SOUTHWEST NEBRASKA...AS SOME MODEL DATA NOT INDICATING THE FOG. FEEL
THOUGH THAT WITH THE RECENT RAINFALL AND LIGHT WINDS TONIGHT...AT
LEAST GROUND FOG WILL DEVELOP. FEEL THE BEST COURSE OF ACTION IS TO
CONTINUE BRINGING THE VISIBILITY DOWN TO IFR AT KLBF DURING THE
EVENING AND CONTINUE THROUGH EARLY MONDAY MORNING. DUE TO
UNCERTAINTY...WILL NOT GO WITH ANY LIFR OR VLIFR AT THIS TIME...BUT
SOME POTENTIAL IS THERE. ACROSS NORTH CENTRAL NEBRASKA...INCLUDING
THE KVTN TERMINAL...STRATUS MAY MOVE SOUTH OUT OF SOUTH DAKOTA MONDAY
MORNING. HERE TOO CONFIDENCE IS LOW...AND WILL NOT INTRODUCE INTO
THE TAF AT THIS TIME. SFC WINDS WILL REMAIN LIGHT THOUGH TONIGHT.

.LBF WATCHES/WARNINGS/ADVISORIES...DENSE FOG ADVISORY UNTIL 10 AM CST MONDAY FOR NEZ007-010-028-029-
038.

SHORT TERM/EXTENDED...MASEK
AVIATION...CDC

AREA FORECAST DISCUSSION...UPDATED

NWS NORTH PLATTE NE

1022 PM CST SUN JAN 27 2013

.UPDATE...

.DISCUSSION...
SFC OBS AND SATELLITE SUGGEST DENSE FOG IS FILLING INTO HOLT AND
BOYD COUNTIES SO THIS AREA HAS BEEN ADDED TO THE DENSE FOG ADVISORY.

.PREV DISCUSSION... /ISSUED 814 PM CST SUN JAN 27 2013/

UPDATE...

PREV DISCUSSION... /ISSUED 529 PM CST SUN JAN 27 2013/

UPDATE...

PREV DISCUSSION... /ISSUED 355 PM CST SUN JAN 27 2013/

SYNOPSIS...

SHORT TERM...

LONG TERM...

AVIATION...

.LBF WATCHES/WARNINGS/ADVISORIES...DENSE FOG ADVISORY UNTIL 10 AM CST MONDAY FOR NEZ007-010-028-029-
038.

SHORT TERM/EXTENDED...CDC
AVIATION...CDC

AREA FORECAST DISCUSSION

NWS BUFFALO NY

929 PM EST TUE JAN 29 2013

.SYNOPSIS...
THERE WILL BE A SOUTHERLY FLOW OF MILD AIR ACROSS THE REGION
TONIGHT AND TOMORROW WITH PERIODS OF RAIN...SOME OF WHICH MAY
FALL AS FREEZING RAIN EARLY ACROSS THE NORTH COUNTRY. A COLD FRONT
WILL SWEEP ACROSS THE REGION LATE TOMORROW AND TOMORROW NIGHT WITH
GUSTY WINDS...RAIN AND SHARPLY FALLING TEMPERATURES. BEHIND THIS
COLD FRONT EXPECT ACCUMULATING LAKE EFFECT SNOW IN THE TRADITIONAL
SNOWBELTS EAST AND SOUTHEAST OF THE LAKES FOR THE END OF THE WEEK.

.NEAR TERM /THROUGH WEDNESDAY/...
THROUGH THIS EVENING...AN AREA OF SHOWERS IS MOVING ACROSS THE
REGION...TRACKING TO THE EAST-NORTHEAST. THERE HAVE BEEN A FEW
LIGHTNING STRIKES WITH THIS...WITH A RUMBLE OF THUNDER STILL
POSSIBLE THIS EVENING. THE HRRR MODEL HAS A GOOD HANDLE ON THIS...WITH
THE STEADIEST SHOWERS LIKELY TO MOVE ACROSS THE REGION DURING THE
EVENING HOURS...EXITING TO THE NORTH AROUND MIDNIGHT. THUS
FAR...THE NAM/RGEM HAVE BEEN OVERDONE IN QPF EAST OF LAKE
ONTARIO...OTHERWISE THESE MODELS ARE IN GENERAL AGREEMENT WITH THE
HRRR AND RADAR TRENDS. WILL CONTINUE WITH A PERIOD OF CATEGORICAL
POPS FOR MOST LOCATIONS...BUT SPEED UP THE EXIT A BIT BASED ON THE
ABOVE DISCUSSION.

TEMPERATURES HAVE RISEN INTO THE LOWER 50S ACROSS MUCH OF WESTERN
NEW YORK AS WARMER TEMPERATURES ALOFT MIX DOWN...AND HAVE STARTED
TO WARM EAST OF LAKE ONTARIO. BY NOW...EXPECT ALL AREAS ARE ABOVE
FREEZING...WHICH ALLOWS US TO DROP THE WINTER WEATHER ADVISORY.

THE COMBINATION OF WARM DEW POINTS AND LINGERING SNOW PACK HAS
RESULTED IN AREAS OF FOG ACROSS THE REGION. VISIBILITY HAS
IMPROVED ENOUGH TO END THE DENSE FOG ADVISORY ACROSS THE SOUTHERN
TIER...HOWEVER FOG SHOULD INCREASE EAST OF LAKE ONTARIO AS DEW
POINTS RISE.

AS THIS UPPER LEVEL SHORTWAVE NEARS THE SOUTHERN PLAINS LOW...THE
SURFACE LOW WILL DEEPEN AS IT NEARS THE CENTRAL GREAT LAKES REGION
TOMORROW MORNING. A 75 TO 80 KNOT LOW LEVEL JET 3K FEET OFF THE
GROUND AHEAD OF THIS SURFACE LOW WILL REACH INTO THE SOUTHWESTERN
PORTIONS OF OUR CWA AFTER MIDNIGHT...AND SLIGHTLY WEAKER FARTHER
EASTWARD. THOUGH WARM AIR ADVECTION SHOULD PREVENT THESE STRONGER
WIND GUSTS FROM MIXING DOWN...A SUSTAINED WIND MAY REACH AS HIGH AS
25 TO 30 KNOTS ACROSS MAINLY THE HIGHER ELEVATIONS OF THE SOUTHERN
TIER. WILL HOIST A WIND ADVISORY FOR THIS REASON...AND CONTINUE THE
ADVISORY INTO THURSDAY. AS THE LOW LEVEL JET PASSES EASTWARD LATER
WEDNESDAY THERE MAY BE A TIME OF SLIGHTLY WEAKER WINDS.

WEDNESDAY THE SURFACE LOW OVER THE CENTRAL GREAT LAKES WILL CONTINUE
TO DEEPEN AS IT PASSES JUST TO THE NORTH OF THE REGION. WITH THE
INCREASING PRESSURE GRADIENT GUSTY WINDS WILL CONTINUE THROUGH THE
DAY WEDNESDAY.

THIS DEEPENING SURFACE LOW WILL DRAG A COLD FRONT TO NEAR WESTERN
NEW YORK BY 00Z...HOWEVER BOTH THE NAM AND GFS ARE SUGGESTING A
SURFACE TROUGH AHEAD OF THE COLD FRONT MAY BRING A LINE OF SHOWERS
INTO THE REGION LATE MORNING TOWARDS THE WEST AND THEN EASTWARD
ACROSS THE CWA IN THE AFTERNOON. WHILE INSTABILITY WILL REMAIN
MARGINAL...THE UPPER LEVEL DYNAMICS OF A POTENT SHORTWAVE AND STRONG
HEIGHT FALLS WILL LIKELY LEAD TO THE POSSIBILITY OF THUNDER WITHIN A
POTENTIAL CONVECTIVE SQUALL LINE CROSSING THE REGION.

TEMPERATURES TONIGHT WILL REMAIN STEADY TO SLIGHTLY RISING THROUGH
THE NIGHT. HIGHS TOMORROW BE NEAR RECORD LEVELS WITH HIGHS IN THE
MID 50S...TO LOWER 60S. RECORD HIGHS TOMORROW INCLUDE....BUFFALO 56
(1916)...ROCHESTER 55 (1974)...AND WATERTOWN 52 (2006).

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
SHARP COLD FRONT IS STILL EXPECTED TRACK FROM WEST TO EAST ACROSS
THE AREA DURING THE EVENING HOURS...WITH PROFILES NOT SUPPORTING
SNOW ACROSS MOST AREAS UNTIL AFTER MIDNIGHT. THEREFORE...WE
CONTINUE TO EXPECTED A BAND OF SHOWERS AND EMBEDDED THUNDERSTORMS
TO CROSS THE AREA ALONG AND AHEAD OF THE FRONT DURING THE EVENING.
THERE IS SOME CONCERN FOR A BAND OF ENHANCED WINDS IF THE
CONVECTIVE LINE CAN ORGANIZE SUFFICIENTLY.

FIRST CONCERN BEHIND THE FRONT WILL BE THE POTENTIAL FOR ADVISORY
OR NEAR WARNING LEVEL WINDS. IMPRESSIVELY STRONG COLD ADVECTION
WILL ALLOW FOR DEEP MIXING WITH WINDS GUSTS OF 50 TO 55 MPH
POSSIBLE WEDNESDAY NIGHT THROUGH A GOOD PART OF THURSDAY. A WIND
ADVISORY WILL BE ISSUED FOR THE ENTIRE AREA TO ADDRESS THIS HIGH
WIND POTENTIAL.

TEMPERATURES WILL FALL SHARPLY IN WAKE OF THE FRONT WITH 50S IN
THE EVENING DROPPING INTO THE 20S BY THURSDAY MORNING. A
SECONDARY UPPER TROUGH WILL DIG INTO THE GREAT LAKES THURSDAY
THAT WILL PROVIDE AN INITIAL LAKE EFFECT SETUP AS THE COLD AIR
GRADUALLY DEEPENS. DEPTH OF INSTABILITY NOT OVERLY IMPRESSIVE
INITIALLY AND THINK ACCUMULATIONS WILL BE LIMITED TO JUST A
COUPLE INCHES...ACROSS PRIMARILY THE CHAUTAUQUA RIDGE AS WELL AS
THE TUG HILL.

THE COLD AIR WILL CONTINUE TO DEEPEN THURSDAY AFTERNOON AND
THURSDAY NIGHT...WITH 850 MB TEMPERATURES DROPPING TO NEAR -20C
BY FRIDAY MORNING. INSPECTION OF NAM BUFR SOUNDINGS SHOWING THAT
THE LAKE RESPONSE WILL BE ON THE UPTICK AFTER 18Z THURSDAY AS THE
PASSING OF A SHORTWAVE SIGNIFICANTLY WEAKENS THE INVERSION AND
ALLOWS EQUILIBRIUM HEIGHTS TO CLIMB TO AROUND 12K FEET. THERE ARE
SEVERAL FACTORS WHICH POINT TO THE POTENTIAL FOR ANOTHER
SIGNIFICANT LAKE EFFECT EVENT FOR THIS PERIOD. BESIDES THE
EXCELLENT OVER-LAKE INSTABILITY WITH LAKE INDUCED CAPES CLIMBING TO
AROUND 700 J/KG...AMBIENT MOISTURE WILL BE MORE THAN ADEQUATE WITH
THE PASSING WAVE. ALTHOUGH THE DENDRITIC GROWTH ZONE WILL BE
RELATIVELY LOW IN THE COLD AIRMASS...WE SHOULD STILL BE ABLE TO
GET SOME DECENT SNOW RATIOS. THE BEST POTENTIAL FOR SIGNIFICANT
ACCUMULATING LAKE SNOWS WILL BE IN FAVORED WESTERLY FETCH AREAS OF
THE SOUTHERN TIER AND EAST OF LAKE ONTARIO. LAKE EFFECT SNOW
WATCHES WILL BE ISSUED FOR THESE AREAS.

.LONG TERM /SATURDAY THROUGH TUESDAY/...
THE LATEST MEDIUM RANGE MODELS AND ENSEMBLE FORECASTS CONTINUING TO
SUGGEST THAT THE COLD AIR ADVECTIVE PATTERN WILL CONTINUE THROUGH
THE WEEKEND...AS THE MEAN TROUGH REMAINS OVER THE GREAT LAKES AND
NEW ENGLAND. THIS WILL RESULT IN TEMPERATURES FALLING BACK TO BELOW
NORMAL LEVELS. PARAMETERS FOR CONTINUED ACCUMULATING LAKE EFFECT
SNOWS CONTINUE TO LOOK GOOD AS 850 MB TEMPERATURES REMAINING AROUND
-20C...COMBINED WITH EXCELLENT 850 MB TO 700 MB MOISTURE. ABOUT
THE ONLY NEGATIVE WILL BE THE LOWER THAN IDEAL INVERSION HEIGHTS
WHICH WILL BE GENERALLY FALL BELOW 7K FEET AND SOME LOSS OF
DENDRITIC GROWTH DEPTH AS MUCH OF THE SATURATED LAYER FALLS BELOW
-18C. THE PASSAGE OF SEVERAL SHORTWAVES WILL KEEP WINDS LESS THAN
STEADY STATE WITH LAKE EFFECT BANDS IMPACTING MULTIPLE AREAS OVER
THE WEEKEND...WITH SOME AREAS STILL HAVING THE POTENTIAL FOR
SIGNIFICANT SNOWS. THE UPPER TROUGH LOOKS TO RETREAT BACK UP INTO
NORTHEAST CANADA BY EARLY NEXT WEEK...ALLOWING FOR A MODERATION IN
TEMPERATURES AND LIKELY AN END TO THE LAKE EFFECT SNOWS.

.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
AN AREA OF STEADY SHOWERS WILL MOVE FROM SW-NE THROUGH 06Z...FIRST
IMPACTING WESTERN TAF SITES. THIS AREA OF ELEVATED CONVECTION HAS
A FEW EMBEDDED THUNDERSTORMS...WHICH MAY BRIEFLY IMPACT BUF/IAG
BEFORE 03Z.

THE MAJORITY OF THE NIGHT SHOULD BE VFR FOR BUF/IAG/ROC...WITH
ONLY LINGERING MVFR CIGS AND LOWER VSBY IN SHOWERS THIS EVENING.
THE 00Z BUFFALO SOUNDING SHOWS A FAIRLY MIXED BOUNDARY
LAYER...WITH CIGS LIKELY TO REMAIN ABOVE THIS. EXPECT LOWER
CONDITIONS AT JHW/ART...WHERE THERE IS STILL SOME SNOWPACK TO
ENHANCE LOW LEVEL MOISTURE AND FOG DEVELOPMENT. EXPECT A GENERAL
IMPROVING TREND AT JHW AS WINDS PICK UP...AND DETERIORATING
CONDITIONS AT ART GIVEN THE DEEP SNOW PACK AND INCREASING DEW
POINTS. IN EACH CASE...FORECAST CONFIDENCE IS LOW...SINCE THE
MIXING OF WINDS WILL PLAY A KEY ROLE.

OTHERWISE...LLWS WILL BE A LINGERING CONCERN FOR THE TAFS
THROUGHOUT THE PERIOD. A LOW LEVEL JET WILL PRODUCE WINDS TO 65
KNOTS AT 1500 FEET...WITH THESE EXPECTED TO STRUGGLE TO MIX TO THE
SURFACE.

ON WEDNESDAY...A LINE OF SHOWERS WILL MOVE ACROSS...WITH AGAIN A
RUMBLE OF THUNDER POSSIBLE. VFR/MVFR CONDITIONS ARE LIKELY...EXCEPT
FOR LOCALLY HEAVY SHOWERS.

OUTLOOK...
THURSDAY THROUGH SATURDAY...MVFR WITH LOCALIZED IFR IN LAKE EFFECT
SNOW SHOWERS EAST OF THE LAKES.
SUNDAY...MAINLY VFR WITH MVFR IN LOCALIZED LAKE EFFECT SNOW SHOWERS.

.MARINE...
WINDS WILL STRENGTHEN MORE TONIGHT AND WEDNESDAY AS THE PRESSURE
GRADIENT INCREASES AHEAD OF THE ADVANCING LOW AND ITS ASSOCIATED
COLD FRONT. SMALL CRAFT ADVISORIES HAVE BEEN ISSUES BEGINNING
TONIGHT INTO WEDNESDAY THEN GALE WATCHES TAKE OVER WITH GALE FORCE
WINDS POSSIBLE WEDNESDAY NIGHT AHEAD AND ALONG THE COLD FRONTAL
PASSAGE.

.HYDROLOGY...
THERE APPEARS TO BE SOME MINOR ICE JAMMING ON SOME OF THE
CREEKS...WITH HYDROGRAPHS SUGGESTING THERE IS OR HAS BEEN SOME ICE
FLOW ON THE CAYUGA CREEK...CAZENOVIA CREEK...BUFFALO CREEK...AND
CATTARAUGUS CREEK...AS WELL AS A SPOTTER REPORT OF ICE FLOWS ON
THE CONEWANGO. IN ALL OF THESE CASES...EXPECT THE ICE IS RATHER
THIN...WITH ANY JAMS LIKELY TO BE RELATIVELY SHORT LIVED. THIS
SAID...WILL CONTINUE TO MONITOR THESE CREEKS...AS IT IS POSSIBLE
THERE WILL BE TEMPORARY AND MINOR ICE JAM FLOODING IN A FEW SPOTS
OVERNIGHT. THIS SHOULD REMOVE AND MELT MUCH OF THE ICE WHICH HAS
FORMED OVER THE PAST PERIOD OF COLD WEATHER.

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...LAKE EFFECT SNOW WATCH FROM THURSDAY AFTERNOON THROUGH LATE
FRIDAY NIGHT FOR NYZ006>008-012-019-020-085.
WIND ADVISORY FROM 1 AM WEDNESDAY TO 1 PM EST THURSDAY FOR
NYZ012-019-020-085.
WIND ADVISORY FROM 6 PM WEDNESDAY TO 1 PM EST THURSDAY FOR
NYZ001>008-010-011-013-014-021.
MARINE...GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR
LEZ020-040-041.
SMALL CRAFT ADVISORY UNTIL 7 PM EST WEDNESDAY FOR LEZ020-
040-041.
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY
AFTERNOON FOR LOZ030-042>045-062>065.
SMALL CRAFT ADVISORY FROM 1 AM TO 9 PM EST WEDNESDAY FOR
LOZ030.
SMALL CRAFT ADVISORY FROM 4 AM TO 9 PM EST WEDNESDAY FOR
LOZ042>045.

SYNOPSIS...THOMAS
NEAR TERM...APFFEL/THOMAS
SHORT TERM...TMA
LONG TERM...TMA
AVIATION...APFFEL/TJP
MARINE...APFFEL/THOMAS
HYDROLOGY...APFFEL

AREA FORECAST DISCUSSION

NWS BUFFALO NY

740 PM EST TUE JAN 29 2013

.NEAR TERM /THROUGH WEDNESDAY/...
THROUGH EARLY EVENING...THE MOST SIGNIFICANT AREA OF SHOWERS IS
JUST NORTH OF LAKE ERIE...TRACKING TO THE EAST-NORTHEAST. THERE HAVE
BEEN A FEW LIGHTNING STRIKES WITH THIS...WITH A RUMBLE OF THUNDER POSSIBLE
ACROSS THE NIAGARA FRONTIER DURING THE EVENING HOURS. THE HRRR
MODEL HAS A GOOD HANDLE ON THIS...WITH THE STEADIEST SHOWERS
LIKELY TO MOVE ACROSS THE REGION DURING THE EVENING HOURS...EXITING
TO THE NORTH AROUND MIDNIGHT. THUS FAR...THE NAM/RGEM HAVE BEEN
OVERDONE IN QPF EAST OF LAKE ONTARIO...OTHERWISE THESE MODELS ARE
IN GENERAL AGREEMENT WITH THE HRRR AND RADAR TRENDS. WILL CONTINUE
WITH A PERIOD OF CATEGORICAL POPS FOR MOST LOCATIONS...BUT SPEED
UP THE EXIT A BIT BASED ON THE ABOVE DISCUSSION.

TEMPERATURES HAVE RISEN INTO THE LOWER 50S ACROSS MUCH OF WESTERN
NEW YORK AS WARMER TEMPERATURES ALOFT MIX DOWN. NORTHEAST WINDS
THROUGH THE SAINT LAWRENCE VALLEY FROM A SURFACE HIGH OVER
SOUTHEASTERN QUEBEC HAVE MAINTAINED A SHALLOW LAYER OF SUBFREEZING
TEMPERATURES ACROSS THE SAINT LAWRENCE VALLEY AND SHELTERED
PORTIONS OF THE NORTH COUNTRY. WHILE THE MAJORITY OF JEFFERSON AND
LEWIS COUNTIES ARE ABOVE FREEZING AS OF EARLY EVENING...THE LIGHT
NORTHEAST FLOW IS TRAPPING SUB-FREEZING AIR IN A FEW SPOTS.
ALSO...THE GROUND WILL LIKELY LAG IN WARMING TO STILL CREATE THE
POTENTIAL FOR ICY SPOTS IN FALLING PRECIPITATION. FOR THESE
REASONS...WILL MAINTAIN THE WINTER WEATHER ADVISORY FOR
NOW...WITH A RAPID RISE IN TEMPERATURES LIKELY LATER THIS EVENING
EAST OF LAKE ONTARIO.

.AVIATION /01Z WEDNESDAY THROUGH SUNDAY/...
AN AREA OF STEADY SHOWERS WILL MOVE FROM SW-NE THROUGH 06Z...FIRST
IMPACTING WESTERN TAF SITES. THIS AREA OF ELEVATED CONVECTION HAS
A FEW EMBEDDED THUNDERSTORMS...WHICH MAY BRIEFLY IMPACT BUF/IAG
BEFORE 03Z.

OTHERWISE...LLWS WILL BE A LINGERING CONCERN FOR THE TAFS
THROUGHOUT THE PERIOD. A LOW LEVEL JET WILL PRODUCE WINDS TO 65
KNOTS AT 1500 FEET...WITH THESE EXPECTED TO STRUGGLE TO MIX TO THE
SURFACE.

ON WEDNESDAY...A LINE OF SHOWERS WILL MOVE ACROSS...WITH AGAIN A
RUMBLE OF THUNDER POSSIBLE. VFR/MVFR CONDITIONS ARE LIKELY...EXCEPT
FOR LOCALLY HEAVY SHOWERS.

OUTLOOK...
THURSDAY THROUGH SATURDAY...MVFR WITH LOCALIZED IFR IN LAKE EFFECT
SNOW SHOWERS EAST OF THE LAKES.
SUNDAY...MAINLY VFR WITH MVFR IN LOCALIZED LAKE EFFECT SNOW SHOWERS.

.MARINE...
SOME DENSE FOG WILL BE FOUND OVER THE LAKES THIS MORNING WITH THE
VERY MOIST AIRMASS THAT HAS SHIFTED OVER THE LOWER LAKES. SOUTHERLY
WINDS WILL BEGIN TO PICK UP THIS AFTERNOON AS A DEEPENING AREA OF LOW
PRESSURE LIFTS NORTH ACROSS THE UPPER MIDWEST. WINDS WILL STRENGTHEN
MORE TONIGHT AND WEDNESDAY AS THE PRESSURE GRADIENT INCREASES AHEAD
OF THE ADVANCING LOW AND ITS ASSOCIATED COLD FRONT. SMALL CRAFT
ADVISORIES HAVE BEEN ISSUES BEGINNING TONIGHT INTO WEDNESDAY THEN
GALE WATCHES TAKE OVER WITH GALE FORCE WINDS POSSIBLE WEDNESDAY
NIGHT AHEAD AND ALONG THE COLD FRONTAL PASSAGE.

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...LAKE EFFECT SNOW WATCH FROM THURSDAY AFTERNOON THROUGH LATE
FRIDAY NIGHT FOR NYZ006>008-012-019-020-085.
WIND ADVISORY FROM 1 AM WEDNESDAY TO 1 PM EST THURSDAY FOR
NYZ012-019-020-085.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
NYZ007-008.
WIND ADVISORY FROM 6 PM WEDNESDAY TO 1 PM EST THURSDAY FOR
NYZ001>008-010-011-013-014-021.
MARINE...GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR
LEZ020-040-041.
SMALL CRAFT ADVISORY UNTIL 7 PM EST WEDNESDAY FOR LEZ020-
040-041.
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY
AFTERNOON FOR LOZ030-042>045-062>065.
SMALL CRAFT ADVISORY FROM 1 AM TO 9 PM EST WEDNESDAY FOR
LOZ030.
SMALL CRAFT ADVISORY FROM 4 AM TO 9 PM EST WEDNESDAY FOR
LOZ042>045.

SYNOPSIS...THOMAS
NEAR TERM...THOMAS
SHORT TERM...TMA
LONG TERM...TMA
AVIATION...APFFEL/TJP
MARINE...THOMAS
HYDROLOGY...APFFEL

AREA FORECAST DISCUSSION

NWS BUFFALO NY

747 AM EST MON JAN 28 2013

.SYNOPSIS...
WARMER TEMPERATURES WILL ARRIVE TODAY AS A WARM FRONT PUSHES NORTH
ACROSS THE REGION. THIS WARM UP WILL BRING THE THREAT FOR A PERIOD
OF MIXED SNOW, SLEET AND FREEZING RAIN AT THE ONSET BEFORE
CHANGING TO ALL RAIN FROM SOUTHWEST TO NORTHEAST. WARM AND RAINY
WEATHER WILL CONTINUE TUESDAY AND WEDNESDAY. MUCH COLDER WEATHER
WILL RETURN WEDNESDAY NIGHT AS A COLD FRONT CROSSES THE LOWER
GREAT LAKES SETTING THE STAGE FOR ACCUMULATING LAKE EFFECT SNOWS
THURSDAY AND FRIDAY.

.NEAR TERM /THROUGH TONIGHT/...
THE MAIN FORECAST CONCERN FOR THIS MORNING WILL CONTINUE TO BE FOR
MIXED PRECIPITATION ADVANCING NORTH AND EAST ACROSS WESTERN NEW YORK.
AT 7 AM THE 11Z RAP 925MB 0C ISOTHERM HAS LIFTED NORTH ACROSS
CHAUTAUQUA AND WESTERN CATTARAUGUS COUNTIES THROUGH THE NIAGARA
FRONTIER AND INTO THE GENESEE RIVER VALLEY. THE 3C ISOTHERM IS
LOCATED FROM BUFFALO SOUTHWARD WITH SURFACE TEMPS 30 AND BELOW IN
THESE AREAS. THIS INDICATES THAT WARM AIR IS OVERSPREADING THE COLD
DENSE AIR AT THE SURFACE WITH PRECIPITATION PHASE CHANGE OCCURRING
AS IT FALLS FROM COLD TO WARM TO COLD AGAIN. BUFFALO RADAR
REFLECTIVITY SHOWING PRECIPITATION HAS SPREAD NORTH AND EAST ACROSS
MUCH OF THE FORECAST AREA.

FREEZING RAIN IS BEING REPORTED AT BUFFALO AND NIAGARA FALLS DOWN TO
WELLSVILLE WHERE THE WARM NOSE ALOFT HAS RISEN GREATER THAN 3C. SOME
DOWNSLOPING OFF THE CHAUTAUQUA RIDGE HAS ALLOWS TEMPS TO WARM TO 36
FOR DUNKIRK SO RAIN IS BEING REPORTED THERE. SNOW AND SLEET IS
FALLING EAST OF I-390 WHERE THE WARM NOSE ALOFT HAS NOT WARMED ENOUGH
FOR FREEZING RAIN. A PEEK AT THE CORRELATION COEFFICIENT PRODUCT ON
THE DUAL-POL INDICATES A LARGE AREA OF SLEET MIXING IN OVER ALLEGANY
COUNTY NORTH TO JUST WEST OF ROCHESTER AS CC VALUES WERE RUNNING
BETWEEN 0.85 AND 0.95 INDICATING HYDROMETEORS BECOMING
MIS-SHAPED...ICING/SLEET OCCURRING.

THE PRECIPITATION IS BEING FORCED BY A WARM FRONT LIFTING NORTH
ACROSS THE OHIO VALLEY AND ALONG A 60 KT LOW LEVEL JET OVER INDIANA
AMD WESTERN OHIO. THROUGH TODAY THE WARM FRONT WILL LIFT NORTH
ACROSS NEW YORK WITH BOUNDARY LAYER TEMPS CONTINUING TO WARM ABOVE
FREEZING. IT STILL APPEARS THAT MOST LOCATIONS WILL RECEIVE ABOUT A
3 TO 5 HOUR PERIOD OF MIXED PRECIPITATION BEFORE CHANGING OVER TO
RAIN. THE BEST CHANCE FOR THE LONGEST DURATION OF PROFILES
SUPPORTIVE OF FREEZING PRECIPITATION WILL BE ACROSS EASTERN PORTIONS
OF THE SOUTHERN TIER...FINGER LAKES AND EVENTUALLY NORTH COUNTRY. IT
PROBABLY SHOULD BE NOTED THAT EVEN AFTER TEMPERATURES RISE ABOVE
FREEZING...THE RECENT VERY COLD TEMPERATURES AND COLD GROUND MAY
STILL SUPPORT AN INCREASED DURATION OF PRECIPITATION FREEZING ON
SURFACES.

MODEL QPF NOT OVERLY IMPRESSIVE WITH THIS EVENT WITH NEARLY ALL
AVAILABLE GUIDANCE SUGGESTING AMOUNTS GENERALLY A HALF INCH OR LESS.
SNOWFALL AMOUNTS GENERALLY IN THE 1-3 INCH RANGE FOR WESTERN NEW
YORK WITH LONGER DURATION OF SNOW FOR THE NORTH COUNTRY LIKELY
PRODUCING AS MUCH AS 3-5 INCHES THROUGH TODAY AND TONIGHT.
ICE ACCUMULATIONS WILL HOLD TO A TENTH OF AN INCH OR LESS FOR THE
MAJORITY OF LOCATIONS BUT SECTIONS OF THE SOUTHERN FINGER LAKES AND
UPPER GENESEE VALLEY COULD SEE UPWARDS OF A QUARTER INCH ESPECIALLY
IN COLDER VALLEYS. DUE TO THE ANTICIPATED FREEZING PRECIPITATION ON
TOP OF THE INITIAL MINOR SNOWFALL AMOUNTS...A WINTER WEATHER
ADVISORY REMAINS IN EFFECT TODAY FOR THE ENTIRE AREA.

GOING INTO THE AFTERNOON EVENTUALLY THE WARMER AIR BUILDS DOWN TO
THE SURFACE AND PROFILES WILL SUPPORT JUST PLAIN RAIN. THE ENDING
TIMES OF THESE ADVISORIES CORRELATE WITH WHEN WE EXPECT
PRECIPITATION TO BE ALL RAIN. HIGHS TODAY WILL REACH TO AROUND 40
FOR MUCH OF WNY WITH 30S AND EVEN UPPER 20S IN THE VALLEYS OF THE
NORTH COUNTY WHERE LONGER DURATION OF SNOW AND MIXED PRECIP IS
EXPECTED. THE LOW LEVEL JET HELPING TO DRIVE THE WEATHER TODAY WILL
ALSO CREATE SOME GUSTY WINDS ACROSS THE SOUTHERN TIER DURING THE
LATE MORNING AND AFTERNOON BUT WILL STAY BELOW WIND ADVISORY
CRITERIA.

FOR TONIGHT THE CENTER OF THE STORM SYSTEM WILL LIFT FROM NEAR
MICHIGAN EASTWARD AND ACROSS OUR FORECAST AREA WITH THE WARM FRONT
ALSO LIFTING NORTH AND EAST. EXPECT PRECIPITATION TYPE FOR ALL OF
WESTERN AND LOWER CENTRAL NY TO BE RAIN WITH SNOW CONTINUING ACROSS
THE NORTH COUNTRY. EVENTUALLY THE WARM NOSE WILL SPREAD OVER EASTERN
LAKE ONTARIO COUNTIES AS WELL WITH SLEET AND FREEZING RAIN MIXED
PRECIP. SURFACE TEMPS WILL REMAIN NEARLY STEADY OVERNIGHT IN THE
UPPER 30S TO LOWER 40S ACROSS WESTERN NY AND EVENTUALLY INCHING
ABOVE FREEZING ACROSS THE NORTH COUNTY.

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
WET AND VERY MILD WEATHER WILL CHARACTERIZE THE INITIAL PORTION OF
THIS PERIOD AS WARM AIR SURGES NORTHWARDS ACROSS THE REGION AHEAD OF
AN APPROACHING COLD FRONT THAT WILL MARCH EASTWARDS ACROSS THE GREAT
LAKES WEDNESDAY NIGHT...CROSSING WESTERN AND CENTRAL NEW YORK WHILE
USHERING IN THE RETURN OF WINTER ALONG WITH THE LIKELIHOOD OF
SIGNIFICANT LAKE EFFECT SNOWS FOR THE LATTER HALF OF THE WEEK.

THE BULK OF THE INITIAL WAVE OF PRECIPITATION ASSOCIATED WITH THE
WARM FRONT CURRENTLY MOVING INTO WESTERN NEW YORK WILL HAVE PUSH
EAST ACROSS NEW ENGLAND BY TUESDAY MORNING...HOWEVER A LINGERING
SURFACE TROUGH ALONG WITH PLENTY OF MOISTURE REMAINING IN PLACE
SHOULD ALLOW FOR AT LEAST A CHANCE OF SHOWERS TO START OUT THE DAY
WITH POPS RAMPING UP ONCE AGAIN BY THE AFTERNOON AS ANOTHER WARM
FRONT LIFTS NORTH ACROSS THE REGION WITH DEEPER MOISTURE RIDING OVER
THE TOP OF AN UPPER LEVEL RIDGE CROSSING THE OHIO VALLEY AND LOWER
GREAT LAKES. THIS WARM FRONTAL BOUNDARY MARKS THE LEADING EDGE OF AN
EXCEPTIONALLY WARM AIRMASS WITH 850MB TEMPERATURES AS HIGH AS +10C
ADVECTING NORTH INTO WESTERN AND CENTRAL NEW YORK. THIS AIRMASS WILL
MAKE IT FEEL MORE LIKE LATE MARCH/EARLY APRIL AS TEMPERATURES RISE
INTO THE LOWER 50S FROM THE GENESEE VALLEY WEST WHILE AREAS EAST
WILL STAY IN THE 40S.

THE WARMUP WILL CONTINUE UNABATED TUESDAY NIGHT WITH ANY DIURNAL
COOLING BEING OFFSET BY THE CONTINUED WARM ADVECTION ALONG WITH
CLOUD COVER/ONGOING PRECIP AS THE WARM FRONTAL BAND LIFTS NORTH AND
EAST ACROSS THE AREA. EXTENSIVE ISENTROPIC LIFTING ALONG THIS
FRONTAL BAND WILL RESULT IN QPF APPROACHING HALF AN INCH
OVERNIGHT...HOWEVER THERE ARE DISRCREPANCIES AMONG THE MODELS ON THE
EXACT PLACEMENT OF THE FRONT AND ASSOCIATED AXIS OF HEAVIEST RAIN.
HOWEVER AT THIS POINT IT APPEARS THAT GREATEST POPS WILL BE NORTH OF
THE THRUWAY WHILE AREAS SOUTH MAY STAY IN THE DRIER WARM SECTOR.
TEMPERATURES ACROSS THE NORTH COUNTRY WILL GRADUALLY WARM THROUGH
THE NIGHT INTO THE LOWER 50S WHILE THE REST OF THE FORECAST AREA
WILL SLOWLY CLIMB INTO THE LOW TO MID 50S BY DAYBREAK WEDNESDAY.
ANOTHER ISSUE ASSOCIATED WITH THE ADVECTION OF WARM MOIST AIR
NORTHWARDS ACROSS THE COLD LAKES WILL BE FOG AND HAVE UPDATED GRIDS
TO INCLUDE THIS. AS THE WINDS WILL BE RELATIVELY BREEZY OUT OF THE
SOUTH...WILL ASSUME THAT MOST OF THE LAND AREAS OF THE FORECAST AREA
SHOULD STAY FOG FREE...HOWEVER THE NIAGARA FRONTIER FROM DOWNTOWN
BUFFALO NORTH ACROSS NIAGARA COUNTY MAY BE THE RECIPIENTS OF
ADVCETION FOG OFF LAKE ERIE IF THERE IS ANY SOUTHWESTERLY COMPONENT
TO THE WINDS.

WE WILL SEE A VERY BALMY TO WEDNESDAY AS THE AREA WILL BE FIRMLY IN
THE WARM SECTOR OF A BROAD AREA OF LOW PRESSURE EXTENDING ACROSS THE
MIDWEST AND CENTRAL GREAT LAKES. THERE ARE SIGNIFICANT DIFFERENCES
BETWEEN THE GFS/NAM WHICH RAPIDLY DEVELOP A VERY DEEP LOW OVER THE
CENTRAL GREAT LAKES FROM A WAVE MOVING UP THE FRONT MARKING THE
BOUDNARY BETWEEN THE WARM AIR OVER THE EASTERN U.S. AND A SUB-ARCTIC
BLAST OF COLD AIR DROPPING ACROSS THE NORTHERN PLAINS OUT OF CANADA.
ON THE OTHER HAND THE ECMWF FEATURES A WEAKER SERIES OF WAVES THAT
WORK THEIR WAY ALONG THE SLOWER MOVING FRONTAL BOUDNARY...WITH NO
SINGLE LOW BECOMING DOMINANT. THIS HAS A SIGNIFICANT IMPACT ON THE
WIND FORECAST FOR OUR AREA AS A NAM/GFS SOLUTION WITH THE DEEP LOW
TRACKING OUT THE CENTRAL LAKES COULD MEAN A SIGIFICANT WIND EVENT
ACROSS THE AREA...WHILST THE ECMWF SOLUTION WOULD BE MUCH MORE
BENIGN. GIVEN THE UNCERTAINTY...THE CURRENT FORECAST WILL LEAN MORE
TOWARDS THE ECMWF SOLUTION...WHICH ALSO PRESERVES CONTINUITY WITH
THE PREVIOUS FORECAST. THUS...STILL EXPECT A FRONTAL PASSAGE LATE
WEDENSDAY AFTERNOON/WEDNESDAY EVENING WITH BREEZY...BUT NOT
DAMAGING...SOUTH WINDS VEERING TO THE SOUTHWEST AND EVENTUALLY TO
THE WEST AS TEMPERATURES FALL FROM THE MID 50S EARLY WEDNESDAY TO
THE UPPER 20S/LOWER 30S WEDNESDAY NIGHT. ACCOMPANYING THIS FRONTAL
PASSAGE WILL BE ANOTHER DECENT SOAKING RAIN WITH A QUARTER TO A HALF
INCH OF QPF POSSIBLE...DEPENDING ON HOW FAST THE FRONT MOVES
THROUGH. BY EARLY THURSDAY MORNING...WE SHOULD SEE TEMPERATURES COOL
TO THE POINT THAT LAKE EFFECT SHOWERS SHOULD BEGIN TO DEVELOP...

.LONG TERM /THURSDAY THROUGH SUNDAY/...
FOLLOWING THE PASSAGE OF THE MIDWEEK COLD FRONT...THE MEDIUM RANGE
GUIDANCE REMAINS IN EXCELLENT AGREEMENT THAT BROAD UPPER TROUGHING
WILL BECOME RE-ESTABLISHED ACROSS THE GREAT LAKES AND NORTHEAST
THURSDAY AND FRIDAY...WITH TEMPERATURES TUMBLING BACK TO WELL BELOW
AVERAGE AS PROGRESSIVELY COLDER AIR FLOODS EAST ACROSS THE GREAT
LAKES. WHILE THE INCOMING COLDER AIRMASS DOES NOT LOOK TO BE NEARLY
QUITE AS COLD AS THE ONE THAT AFFECTED OUR REGION FOR MUCH OF LAST
WEEK...850 MB TEMPS STILL LOOK TO DROP TO THE VICINITY OF -18C TO
-20C...WHICH WILL BE PLENTY COLD ENOUGH TO RESULT IN DAYTIME HIGHS
FALLING BACK TO AROUND 20 BY FRIDAY...AND THE DEVELOPMENT OF ANOTHER
ROUND OF POTENTIALLY SIGNIFICANT LAKE EFFECT SNOWS DOWNWIND OF THE
LAKES.

WHILE IT IS STILL TOO EARLY TO DEFINITIVELY PIN DOWN EXACTLY WHICH
AREAS THE LAKE SNOWS MIGHT FOCUS ON...BOTH THE GFS/ECMWF CONTINUE TO
SUGGEST THAT THE LAKE EFFECT ACTIVITY WILL DEVELOP IN A WESTERLY
FLOW REGIME LATER WEDNESDAY NIGHT/EARLY THURSDAY...BEFORE
INTENSIFYING OVER TIME THURSDAY AS AN INITIALLY DRY AIRMASS MOISTENS
IN ADVANCE OF AN APPROACHING SECONDARY SURFACE TROUGH. AFTER THAT
TIME...SOME DISAGREEMENT EMERGES WITH THE ECMWF PUSHING THE SURFACE
TROUGH THROUGH LATER THURSDAY NIGHT/EARLY FRIDAY WITH THE LOW LEVEL
FLOW GOING MORE NORTHWESTERLY ON FRIDAY FOLLOWING ITS PASSAGE...
WHILE THE GFS ESSENTIALLY WASHES OUT THE TROUGH AND KEEPS MORE OF A
WESTERLY FLOW IN PLACE THROUGH FRIDAY.

DOWNWIND OF LAKE ERIE...ALL OF THIS WOULD SUGGEST THE STRONGEST AND
MOST ORGANIZED LAKE SNOWS INITIALLY DEVELOPING ACROSS THE WESTERN
SOUTHERN TIER AND SOUTHERN ERIE AND WYOMING COUNTIES LATER WEDNESDAY
NIGHT INTO THURSDAY...THEN EITHER LINGERING PRETTY MUCH IN PLACE
THROUGH FRIDAY...OR SHIFTING A BIT FURTHER SOUTH TO AREAS SOUTHEAST
OF THE LAKE DEPENDING UPON WHETHER THERE ACTUALLY IS A SECONDARY
TROUGH PASSAGE AND ASSOCIATED WIND SHIFT. SIMILARLY...THE LAKE
ONTARIO LAKE SNOWS WOULD LIKELY DEVELOP ACROSS THE TUG HILL REGION
WEDNESDAY NIGHT INTO THURSDAY...THEN EITHER REMAIN IN PLACE THROUGH
FRIDAY OR MIGRATE SOUTHWARD TO AREAS SOUTHEAST OF THE LAKE.

CONSIDERING THE ABOVE...WILL INDICATE SOME BROAD AREAS OF HIGHER
PRECIPITATION CHANCES EAST OF THE LAKES ON THURSDAY...THEN EXPAND
THESE TO COVER AREAS BOTH EAST AND SOUTHEAST OF THE LAKES THURSDAY
NIGHT AND FRIDAY GIVEN THE INCREASING UNCERTAINTY IN WIND DIRECTION
AND RESULTANT BAND PLACEMENT DURING THESE TWO PERIODS. IN TERMS OF
ACTUAL POP VALUES...WILL INCREASE POPS TO LOW LIKELY WITHIN THE MORE
FAVORED LAKE EFFECT REGIONS ON THURSDAY GIVEN CONTINUED GOOD
AGREEMENT DURING THIS TIME FRAME...BEFORE DROPPING THESE BACK TO
HIGH CHANCE FOR THURSDAY NIGHT AND FRIDAY GIVEN THE INCREASING
FORECAST UNCERTAINTY. OUTSIDE OF THE MORE FAVORED LAKE EFFECT
AREAS...WILL KEEP SOMEWHAT LOWER CHANCE POPS IN PLAY BOTH TO COVER
THE APPROACH AND POSSIBLE PASSAGE OF THE SECONDARY SURFACE TROUGH...
AND TO ALSO REFLECT THE INHERENT UNCERTAINTY IN DELINEATING SPECIFIC
AREAS OF LAKE EFFECT THIS FAR OUT.

NEEDLESS TO SAY...IT IS STILL WAY TOO EARLY TO EVEN CONSIDER ANY
FLAGS FOR THIS PERIOD JUST YET...THOUGH GIVEN THE CONSISTENTLY
FAVORABLE SYNOPTIC PATTERN AND THERMODYNAMIC ENVIRONMENT SEEN IN THE
GUIDANCE IN THE THURSDAY-FRIDAY PERIOD...WILL ELECT TO ADD AN
INITIAL MENTION OF THE LAKE EFFECT POTENTIAL TO THE HWO.

LATER ON IN THE PERIOD...BOTH THE GFS AND ECMWF INDICATE THAT A
DECENT CLIPPER-TYPE SYSTEM WILL ROUND THE BASE OF THE MEAN TROUGH
AND WORK INTO OUR REGION SOMETIME BETWEEN FRIDAY NIGHT AND
SATURDAY...THEN EXIT TO OUR EAST ON SUNDAY WITH A REINFORCING SHOT
OF COLDER AND DRIER AIR FOLLOWING ITS PASSAGE. IN TERMS OF
PRECIPITATION CHANCES...THIS FEATURE WILL BRING A MORE GENERAL
CHANCE OF SNOW SHOWERS BACK INTO THE AREA FOR THE WEEKEND...WHILE
ALSO INFLUENCING THE EVOLUTION OF THE LOW-LEVEL WIND FIELD...WHICH
IN TURN WILL IMPACT THE ULTIMATE POSITION AND STRENGTH OF ANY LAKE
SNOWS. GIVEN THE DISTANT DAY 6-7 TIME FRAME AND THE TYPICAL FORECAST
UNCERTAINTY IN BOTH THE TIMING/TRACK/STRENGTH OF THIS FEATURE AND
ITS EXACT INFLUENCE ON THE LOW LEVEL WIND FIELDS...FOR NOW HAVE JUST
TRENDED POPS BACK TO THE BROADBRUSH LOW-MID CHANCE RANGE FOR NEXT
WEEKEND.

.AVIATION /13Z MONDAY THROUGH FRIDAY/...
FREEZING RAIN HAS WORKED NORTH ACROSS FAR WESTERN NY WITH A MIX OF
SNOW AND SLEET FOR KROC AND ALL SNOW NOW ARRIVING AT KART. CIGS AND
VIS ARE RUNNING MVFR/IFR IN ALL AREAS. A 50 TO 60 KNOT LOW LEVEL JET
WHICH IS FORCING THIS PRECIPITATION WILL SHIFT OVER THE REGION BRINGING
THE POSSIBILITY OF SOME LOW LEVEL WIND SHEAR TODAY AS AN INVERSION
ALOFT SEALS OFF THESE HIGH WINDS FROM THE SURFACE.

GOING INTO THE AFTERNOON FOR WNY...THE AIR
MASS WILL BECOME WARM ENOUGH DOWN TO THE SURFACE FOR A CHANGE OVER
TO ALL RAIN. EXPECT THE LIQUID PRECIP TO TAPER OFF CLOSER TO THE
EVENING AND TRANSITION TO DRIZZLE AND LIGHT FOG. PRECIPITATION WILL
REMAIN IN A MIXED PHASE WELL INTO THE EVENING AND OVERNIGHT FOR
KART.

OUTLOOK...
TUESDAY...MVFR WITH RAIN SHOWERS LIKELY.
WEDNESDAY...MVFR/IFR WITH RAIN OR SNOW SHOWERS LIKELY.
THURSDAY AND FRIDAY...MVFR/LOCALIZED IFR IN LAKE EFFECT SNOW
SHOWERS.

.MARINE...
A WARM FRONT IS LIFTING NORTH TOWARD THE LAKES EARLY THIS MORNING.
AN ASSOCIATED LOW LEVEL JET WILL ALSO BRING SOME HIGHER WINDS TO
LAKE ERIE WHERE A SMALL CRAFT ADVISORY HAS BEEN ISSUED. A WINTRY MIX
OF PRECIPITATION WILL OCCUR OVER THE LAKES THROUGH TODAY AS THE
WARMER AIR SLOWLY WORKS NORTHWARD. SOUTHERLY WINDS WILL BUILD WAVES
ALONG THE NORTHERN LAKE SHORES TODAY THROUGH WEDNESDAY BUT EXPECT
THESE TO GENERALLY REMAIN BELOW SMALL CRAFT CRITERIA.

.HYDROLOGY...
WITH THE UPCOMING STRONG WARMUP...NORMALLY ONE WOULD EXPECT THE
POTENTIAL FOR SOME ICE JAMS ON AREA CREEKS GIVEN THE TIME OF YEAR.
THIS SAID...THIS WINTER HAS BEEN RELATIVELY MILD MUCH OF THE TIME...
WITH THE BULK OF ANY ICE FORMATION ON CREEKS LIKELY COMING DURING
OUR STRONG COLD SPELL OF THE PAST WEEK...WITH ANY ICE PROBABLY NOT
YET REACHING THICKNESSES THAT WOULD POSE A SIGNIFICANT ICE JAM
THREAT. THUS...WHILE THESE CANNOT BE AT ALL RULED OUT...AT THIS
POINT WE DO NOT ANTICIPATE A STRONG THREAT OF ICE JAMS AND RESULTANT
FLOODING ISSUES DURING THE UPCOMING WARMUP.

WITH ICE JAMS LIKELY NOT A HUGE CONCERN...AT THIS POINT ANY HYDRO
ISSUES THIS WEEK WILL PROBABLY HAVE TO INSTEAD BE DRIVEN BY A
COMBINATION OF SNOWMELT AND RAINFALL. WITH OVERALL RAINFALL
AMOUNTS LOOKING TO BE RELATIVELY LIGHT THROUGH TUESDAY...
/GENERALLY ON THE ORDER OF A TENTH OR TWO TENTHS OF AN INCH PER
EVERY 12 HOURS/...FEEL THAT ANY HYDRO CONCERNS SHOULD BE
RELATIVELY MINIMAL THROUGH THAT TIME. AFTER THAT...THERE WILL BE
THE POTENTIAL FOR SOMEWHAT HEAVIER SHOWERS ALONG AND IN ADVANCE OF
A COLD FRONT TUESDAY AND WEDNESDAY...WHICH COULD LEAD TO A
SOMEWHAT HIGHER POTENTIAL FOR LOCALIZED HYDRO ISSUES DURING THAT
TIME FRAME.

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR
NYZ005>008.
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
NYZ003-004-013-014.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
NYZ001-002-010>012-019>021-085.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR LEZ040-
041.

SYNOPSIS...SMITH
NEAR TERM...SMITH
SHORT TERM...WOOD
LONG TERM...JJR
AVIATION...SMITH
MARINE...SMITH
HYDROLOGY...JJR

AREA FORECAST DISCUSSION

NWS BUFFALO NY

530 AM EST MON JAN 28 2013

.NEAR TERM /THROUGH TONIGHT/...
THE MAIN FORECAST CONCERN FOR THIS MORNING WILL CONTINUE TO BE FOR
MIXED PRECIPITATION ADVANCING NORTH AND EAST ACROSS WESTERN NEW YORK.
AT 5 AM THE 09Z RAP 925MB 0C ISOTHERM HAS WORKED NORTH ACROSS FAR
WESTERN NEW YORK AND IS SPREADING EAST INTO THE GENESEE RIVER VALLEY
AND SOUTHERN FINGER LAKES WITH SURFACE TEMPS STILL IN THE 20S. THIS
INDICATES THAT WARM AIR IS OVERSPREADING THE COLD DENSE AIR AT THE
SURFACE WITH PRECIPITATION PHASE CHANGE OCCURRING AS IT FALLS FROM
COLD TO WARM TO COLD AGAIN. BUFFALO RADAR REFLECTIVITY SHOWING SNOW
HAS SPREAD NORTH AND EAST ACROSS THE SOUTHERN TIER...NIAGARA
FRONTIER AND INTO THE GENESEE VALLEY. SNOW IS BEING REPORTED AT
OLEAN NORTH TO BUFFALO...NIAGARA FALLS AND ROCHESTER WITH FREEZING
RAIN AT DUNKIRK ON SURFACE OBSERVATIONS. AS WARM AIR INCREASES
ALOFT...SLEET THEN FREEZING RAIN WILL MIX IN AND CHANGE OVER. A PEEK
AT THE CORRELATION COEFFICIENT PRODUCT ON THE DUAL-POL INDICATED
SLEET ALREADY MIXING IN EARLIER NEAR SALAMANCA AND OLEAN AND MOST
RECENTLY IS MIXING IN OVER MUCH OF CHAUTAUQUA...CATTARAUGUS AND INTO
ERIE COUNTY AS CC VALUES WERE RUNNING BETWEEN 0.85 AND 0.95
INDICATING HYDROMETEORS BECOMING MIS-SHAPED...ICING/SLEET OCCURRING.

THE PRECIPITATION IS BEING FORCED BY A WARM FRONT LIFTING NORTH
ACROSS THE OHIO VALLEY AND ALONG A 60 KT LOW LEVEL JET OVER INDIANA.
THROUGH TODAY THE WARM FRONT WILL LIFT NORTH ACROSS NEW YORK WITH
BOUNDARY LAYER TEMPS SLOWLY WARMING ABOVE FREEZING. IT STILL APPEARS
THAT MOST LOCATIONS WILL RECEIVE ABOUT A 3 TO 5 HOUR PERIOD OF MIXED
PRECIPITATION BEFORE CHANGING OVER TO RAIN. THE BEST CHANCE FOR THE
LONGEST DURATION OF PROFILES SUPPORTIVE OF FREEZING PRECIPITATION
WILL BE ACROSS EASTERN PORTIONS OF THE SOUTHERN TIER...FINGER LAKES
AND EVENTUALLY NORTH COUNTRY. IT PROBABLY SHOULD BE NOTED THAT EVEN AFTER
TEMPERATURES RISE ABOVE FREEZING...THE RECENT VERY COLD TEMPERATURES
AND COLD GROUND MAY STILL SUPPORT AN INCREASED DURATION OF
PRECIPITATION FREEZING ON SURFACES.

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
SNOW WITH AREAS OF SLEET AND FREEZING RAIN ARE NOW WORKING NORTH AND
EAST ACROSS WESTERN NY. CIGS AND VIS ARE RUNNING IFR IN THESE AREAS
WITH KROC ABOUT TO DROP TO IFR ONCE THE SNOW ARRIVE. KART IS VFR
WITH SNOW AN HOUR OR TWO AWAY. THROUGH THIS MORNING EXPECT A WINTERY
MIX TO AFFECT ALL TERMINALS WITH KART BEING THE LAST TO SEE THE
ARRIVING SNOW. IFR WILL EVENTUALLY DEVELOP HERE TOO WHEN SNOW ARRIVES.
GOING INTO THE AFTERNOON FOR WNY...THE AIR MASS WILL BECOME WARM
ENOUGH DOWN TO THE SURFACE FOR A CHANGE OVER TO ALL RAIN. EXPECT THE
LIQUID PRECIP TO TAPER OFF CLOSER TO THE EVENING AND TRANSITION TO
DRIZZLE AND LIGHT FOG. PRECIPITATION WILL REMAIN IN A MIXED PHASE
WELL INTO THE EVENING AND OVERNIGHT FOR KART.

OUTLOOK...
TUESDAY...MVFR WITH RAIN SHOWERS LIKELY.
WEDNESDAY...MVFR/IFR WITH RAIN OR SNOW SHOWERS LIKELY.
THURSDAY AND FRIDAY...MVFR/LOCALIZED IFR IN LAKE EFFECT SNOW
SHOWERS.

SYNOPSIS...SMITH
NEAR TERM...SMITH
SHORT TERM...WOOD
LONG TERM...JJR
AVIATION...SMITH
MARINE...SMITH/WOOD
HYDROLOGY...JJR

AREA FORECAST DISCUSSION

NWS BUFFALO NY

510 AM EST MON JAN 28 2013

.AVIATION /10Z MONDAY THROUGH FRIDAY/...
SNOW WITH AREAS OF SLEET AND FREEZING RAIN ARE NOW WORKING NORTH
ACROSS THE SOUTHERN TIER AND NIAGARA FRONTIER. CIGS AND VIS ARE
RUNNING IFR IN THESE AREAS WITH STILL VFR FOR KROC AND KART AS
PRECIP HAS NOT STARTED YET THERE. FROM NOW THROUGH THIS MORNING
EXPECT WINTRY MIX TO AFFECT ALL TERMINALS WEST OF SYRACUSE. NOT
EXPECTING SNOW FOR KART UNTIL AFTER NOONTIME. IFR WILL EVENTUALLY
DEVELOP HERE. GOING INTO THE AFTERNOON FOR WNY...THE AIR MASS WILL
BECOME WARM ENOUGH DOWN TO THE SURFACE FOR A CHANGE OVER TO ALL
RAIN. EXPECT THE LIQUID PRECIP TO TAPER OFF DURING THE LATE
AFTERNOON INTO THE EVENING AND TRANSITION TO DRIZZLE AND LIGHT FOG.
PRECIPITATION WILL REMAIN IN A MIXED PHASE WELL INTO THE EVENING AND
OVERNIGHT FOR KART.

OUTLOOK...
TUESDAY...MVFR WITH RAIN SHOWERS LIKELY.
WEDNESDAY...MVFR/IFR WITH RAIN OR SNOW SHOWERS LIKELY.
THURSDAY AND FRIDAY...MVFR/LOCALIZED IFR IN LAKE EFFECT SNOW
SHOWERS.

SYNOPSIS...SMITH
NEAR TERM...SMITH
SHORT TERM...WOOD
LONG TERM...JJR
AVIATION...SMITH
MARINE...SMITH/WOOD
HYDROLOGY...JJR

AREA FORECAST DISCUSSION

NWS BUFFALO NY

206 AM EST MON JAN 28 2013

.SYNOPSIS...
WARMER TEMPERATURES WILL ARRIVE MONDAY AS A WARM FRONT PUSHES NORTH
ACROSS THE REGION. THIS WARMUP WILL BRING THE THREAT FOR A PERIOD OF
MIXED SNOW...SLEET AND FREEZING RAIN AT THE ONSET BEFORE CHANGING TO
ALL RAIN FROM WEST TO EAST THROUGH MONDAY. WARM AND RAINY WEATHER
WILL CONTINUE TUESDAY AND WEDNESDAY. MUCH COLDER WEATHER WILL RETURN
WEDNESDAY NIGHT AS A COLD FRONT CROSSES THE LOWER GREAT LAKES
SETTING THE STAGE FOR ACCUMULATING LAKE EFFECT SNOWS THURSDAY AND
FRIDAY.

.NEAR TERM /THROUGH TODAY/...
AT 145 AM...MAIN FORECAST CONCERN FOR THE NEAR TERM PERIOD WILL
CONTINUE TO BE FOR MIXED PRECIPITATION ADVANCING NORTH ACROSS NEW
YORK THIS MORNING. AT 1 AM THE 05Z RAP 925MB 0C ISOTHERM WAS
ENTERING CROSSING THE BORDER FROM NORTHWEST PA INTO CHAUTAUQUA COUNTY
WITH ZR ALREADY BEING REPORTED IN KERI. BUFFALO RADAR REFLECTIVITY
SHOWING SNOW IS SPREADING NORTH AND EAST INTO THE SOUTHERN TIER.
STILL EXPECT PRECIPITATION TO START OUT AS SNOW THEN AS WARM AIR
INCREASES ALOFT A CHANGE TO SLEET THEN FREEZING RAIN WILL OCCUR. A
PEEK AT THE CORRELATION COEFFICIENT PRODUCT ON THE DUAL-POL
INDICATED SLEET ALREADY MIXING IN NEAR SALAMANCA AND OLEAN AS CC
VALUES WERE RUNNING BETWEEN 0.85 AND 0.95 INDICATING HYDROMETEORS
BECOMING MIS-SHAPED...ICING OCCURRING.

THE PRECIPITATION IS BEING FORCED BY A WARM FRONT LIFTING NORTH
ACROSS PA AND ALONG A 60 KT LOW LEVEL JET OVER INDIANA.

IT STILL APPEARS THAT MOST LOCATIONS WILL RECEIVE ABOUT A 3 TO 5
HOUR PERIOD OF MIXED PRECIPITATION BEFORE CHANGING OVER TO RAIN. THE
BEST CHANCE FOR THE LONGEST DURATION OF PROFILES SUPPORTIVE OF
FREEZING PRECIPITATION WILL BE ACROSS EASTERN PORTIONS OF THE
SOUTHERN TIER...FINGER LAKES AND NORTH COUNTRY. IT PROBABLY SHOULD
BE NOTED THAT EVEN AFTER TEMPERATURES RISE ABOVE FREEZING...THE
RECENT VERY COLD TEMPERATURES AND COLD GROUND MAY STILL SUPPORT AN
INCREASED DURATION OF PRECIPITATION FREEZING ON SURFACES.

MODEL QPF NOT OVERLY IMPRESSIVE WITH THIS EVENT WITH NEARLY ALL
AVAILABLE GUIDANCE SUGGESTING AMOUNTS GENERALLY A HALF INCH OR LESS.
SNOWFALL AMOUNTS GENERALLY IN THE 1-3 INCH RANGE WITH THE HIGHER END
AMOUNTS ACROSS THE NORTH COUNTRY. ICE ACCUMULATIONS WILL HOLD TO A
TENTH OF AN INCH OR LESS. DUE TO THE ANTICIPATED FREEZING
PRECIPITATION ON TOP OF THE INITIAL MINOR SNOWFALL AMOUNTS...A
WINTER WEATHER ADVISORY HAS BEEN ISSUED FOR THE ENTIRE AREA.

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
MONDAY NIGHT...THE WARM FRONTAL BOUNDARY WILL PUSH INTO THE NORTH
COUNTRY...WITH PRECIPITATION DIMINISHING FROM SOUTHWEST TO NORTHEAST
AS THE INITIAL WEAK WAVE OF LOW PRESSURE AND ASSOCIATED SWATH OF
STRONGER WARM ADVECTION SLIDES OFF INTO EASTERN NEW YORK AND NEW
ENGLAND. ACROSS THE NORTH COUNTRY...CONTINUED WARMING BOTH AT THE
SURFACE AND ALOFT WILL RESULT IN A MIX OF SNOW...SLEET...AND
FREEZING RAIN GRADUALLY TRANSITIONING OVER TO ALL LIQUID...THOUGH
ANY ICING WILL LIKELY REMAIN UNDER A TENTH OF AN INCH GIVEN THE
OVERALL LIGHTENING/DIMINISHING TREND OF THE PRECIP. SOUTH OF THE
WARM FRONT...TEMPS WILL REMAIN WARM ENOUGH FOR ANY LEFTOVER
PRECIPITATION TO FALL ENTIRELY IN THE FORM OF PLAIN LIQUID SOUTH OF
LAKE ONTARIO...WITH STRONG DRYING ALOFT PROBABLY RESULTING IN ALL OF
THIS DEVOLVING INTO AREAS OF LEFTOVER SPOTTY LIGHT RAIN AND OR
DRIZZLE. AS FOR TEMPERATURES...THE ONGOING WARM ADVECTION PATTERN
WILL BE STRONG ENOUGH TO OFFSET ANY NOCTURNAL COOLING...RESULTING IN
TEMPS WARMING SLIGHTLY INTO THE LOWER 40S IN MOST AREAS SOUTH OF
LAKE ONTARIO...WHILE READINGS EAST OF THE LAKE MORE ONLY MORE SLOWLY
RISE OR REMAIN STEADY IN THE LOWER TO MID 30S.

TUESDAY WILL START OFF WITH WEAK SURFACE TROUGHING...THE REMNANTS OF
MONDAY`S WARM FRONT...LINGERING ACROSS NEW YORK STATE DURING THE
MORNING. COUPLED WITH LINGERING LOW LEVEL MOISTURE...THIS WILL LEAD
TO SOME MORE SPOTTY LIGHT SHOWERS OR AREAS OF LIGHT RAIN/DRIZZLE...
FOR WHICH CHANCE POPS WILL REMAIN IN PLAY. AFTER THAT TIME...ANOTHER
COMPLEX LOW PRESSURE SYSTEM WILL LIFT NORTHEASTWARD FROM THE OHIO
VALLEY INTO THE CENTRAL GREAT LAKES AND SOUTHERN ONTARIO...BRINGING
MULTIPLE NOTEWORTHY SURGES OF WARM AIR ADVECTION FOR THE AFTERNOON
AND EVENING ALONG WITH A RENEWED THREAT FOR MORE WIDESPREAD SHOWER
ACTIVITY. IN THE FORECAST...HAVE REFLECTED THIS WITH A RETURN TO
LIKELY POPS FOR TUESDAY AFTERNOON AND EVENING...BEFORE SOME
SEMBLANCE OF A RELATIVE LULL ACROSS PORTIONS OF THE AREA LATER IN
THE NIGHT AS THE MAIN SWATH OF WARM ADVECTION LIFTS OFF TO OUR
NORTH. WITH RESPECT TO TEMPS...THE CONTINUED STRONG WARM AIR
ADVECTION PATTERN WILL ALLOW FOR READINGS TO CLIMB INTO THE UPPER
40S TO LOWER 50S SOUTH OF LAKE ONTARIO ON TUESDAY...WHILE READINGS
EAST OF THE LAKE SEE HIGHS IN THE LOWER TO MID 40S. AS WILL BE THE
CASE WITH MONDAY NIGHT...EXPECT TEMPS TO AGAIN REMAIN RELATIVELY
STEADY OR SLOWLY RISE THROUGH TUESDAY NIGHT GIVEN THE CONTINUED WARM
AIR ADVECTION PATTERN.

ON WEDNESDAY...THE COMPLEX LOW TO OUR WEST WILL LIFT OUT INTO
ONTARIO AND QUEBEC AND SWING ITS ASSOCIATED COLD FRONT EAST ACROSS
OUR REGION...WITH THE 12Z GUIDANCE SUITE CONVERGING ON A GENERAL
AFTERNOON TIMING TO THE FROPA. IN ADVANCE OF THE BOUNDARY...TEMPS
WILL PEAK IN THE 50S IN THE MORNING...BEFORE STARTING TO DROP OFF
AS ONE OR MORE BANDS OF PREFRONTAL/FRONTAL SHOWERS WORK ACROSS THE
REGION...AND THEN FALL MORE QUICKLY AS COLD ADVECTION BEGINS
FOLLOWING THE COLD FRONTAL PASSAGE. THIS SAID...WE STILL EXPECT
CONDITIONS TO REMAIN WARM ENOUGH FOR ALL OF THE PRECIP TO FALL IN
THE FORM OF RAIN SHOWERS DURING WEDNESDAY...BEFORE MIXING WITH AND
EVENTUALLY CHANGING TO SNOW SHOWERS AS IT TAPERS OFF WEDNESDAY
NIGHT.

DEPENDING UPON THE ACTUAL STRENGTH OF THE LOW...IT SHOULD BE NOTED
THAT THERE COULD ALSO BE SOME WIND CONCERNS TUESDAY NIGHT INTO
WEDNESDAY. THE 12Z GFS/NAM/GEM HAVE ALL TRENDED TOWARDS A MUCH
STRONGER MAIN LOW CENTER OVER THE PAST COUPLE OF RUNS...WITH ALL OF
THESE SOLUTIONS DEEPENING THE LOW TO 975 MB AS IT WORKS INTO
SOUTHERN ONTARIO BY LATE WEDNESDAY...WHILE THE MORE CONSISTENT AND
USUALLY MORE RELIABLE ECMWF REMAINS WEAKER WITH A MUCH MORE
ELONGATED LOW WEDNESDAY AFTERNOON AND EVENING. AS A CONSEQUENCE...
THE STRONGER MODELS ALSO HAVE A MUCH STRONGER WIND FIELD SURROUNDING
THE LOW...WITH THE NAM/GFS RESPECTIVELY FORECASTING 90+/80+ KT
SOUTHERLY LOW LEVEL JETS IN ADVANCE OF THE LOW TUESDAY NIGHT INTO
WEDNESDAY... WITH THE GFS THEN ALSO HANGING BACK SOME OF THESE
STRONGER WINDS BACK BEHIND THE COLD FRONTAL PASSAGE WEDNESDAY
AFTERNOON AND EVENING. WERE THESE STRONGER SOLUTIONS TO VERIFY...
THEY WOULD POSE A THREAT OF STRONG WINDS IN BOTH TYPICALLY FAVORED
DOWNSLOPE FLOW REGIONS AND AREAS OF HIGHER TERRAIN TUESDAY NIGHT
INTO WEDNESDAY... WITH THE GFS THEN ALSO SUGGESTING AT LEAST A SMALL
WINDOW FOR SOME MORE WIDESPREAD STRONG WINDS FOLLOWING THE COLD
FROPA LATER WEDNESDAY AFTERNOON AND EVENING. WILL NOT MENTION THIS
POTENTIAL IN THE HWO JUST YET GIVEN THAT WE HAVE ONLY SEEN ONE MODEL
CYCLE`S WORTH OF STRONGER SOLUTIONS...AND IN ONLY SOME OF THE MODELS
AT THAT...HOWEVER THIS POSSIBILITY WILL NEED TO BE CLOSELY WATCHED
OVER THE NEXT FEW DAYS.

.AVIATION /07Z MONDAY THROUGH FRIDAY/...
CONDITIONS WILL BEGIN TO DETERIORATE THIS MORNING EARLY MONDAY AS A
WARM FRONT OVERSPREADING OUR SUB-FREEZING AREA WILL BRING A PERIOD
OF MIXED WINTRY OF PRECIPITATION...INCLUDING THE POTENTIAL OF SLEET
AND FREEZING RAIN. AT 07Z KERI REPORTING FZRA AND BUFFALO RADAR
ALREADY SHOWING SLEET AND SNOW PUSHING NORTH INTO THE SOUTHERN TIER.
THE PRIME THREAT TIME FOR THIS WINTRY MIX AT KJHW/KBUF/KIAG WILL BE
FROM 06Z-12Z AND FOR KROC FROM 10Z-18Z PLUS/MINUS. BEYOND THESE TIME
FRAMES...THE AIR MASS WILL BECOME WARM ENOUGH DOWN TO THE SURFACE
FOR A CHANGE OVER TO ALL RAIN. EXPECT THE LIQUID PRECIP TO TAPER OFF
DURING THE LATE AFTERNOON 18Z-20Z AND TRANSITION TO DRIZZLE AND
LIGHT FOG...LOWERING TO IFR CONDITIONS THROUGH THE END OF THE TAF
PERIOD.

OUTLOOK...
MONDAY NIGHT...MVFR/IFR WITH MIXED PRECIPITATION LIKELY KART.
RAIN/DRIZZLE LIKELY ELSEWHERE.
TUESDAY...MVFR WITH RAIN SHOWERS LIKELY.
WEDNESDAY...MVFR/IFR WITH RAIN OR SNOW SHOWERS LIKELY.
THURSDAY AND FRIDAY...MVFR/LOCALIZED IFR IN LAKE EFFECT SNOW
SHOWERS.

.MARINE...
A WARM FRONT IS LIFTING NORTH TOWARD THE LAKES EARLY THIS MORNING.
THIS WILL BRING A WINTRY MIX OF PRECIPITATION BY MONDAY DAYLIGHT.
SOUTHERLY WINDS WILL BUILD WAVES ALONG THE NORTHERN LAKE SHORES
TODAY THROUGH WEDNESDAY BUT EXPECT THESE TO GENERALLY REMAIN BELOW
SMALL CRAFT CRITERIA.

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...WINTER WEATHER ADVISORY FROM 7 AM THIS MORNING TO 7 PM EST
THIS EVENING FOR NYZ005>008.
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
NYZ003-004-013-014.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
NYZ001-002-010>012-019>021-085.
MARINE...NONE.

SYNOPSIS...TMA
NEAR TERM...SMITH/WCH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...SMITH/WCH
MARINE...SMITH/WCH
HYDROLOGY...JJR

AREA FORECAST DISCUSSION

NWS RALEIGH NC

1220 PM EST MON JAN 28 2013

.SYNOPSIS...
HIGH PRESSURE POSITIONED OFFSHORE WILL CAUSE WARM SOUTHWESTERLY FLOW
ACROSS THE CAROLINAS THROUGH WEDNESDAY. A STRONG COLD FRONT WILL
CROSS THE AREA WEDNESDAY NIGHT.

.NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM MONDAY...

MAIN FORECAST CHALLENGE TODAY IS MAX TEMPS. NEAR TERM MODEL
GUIDANCE SUGGEST MAX TEMPS A GOOD 4-5 DEGREES WARMER THAN CURRENT
FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT INTO THE NORTHERN
COASTAL PLAIN. 12Z GSO SOUNDING INDICATE AS THICK LAYER OF WARM AIR
JUST 500-1000FT OFF THE SURFACE. GFS BUFKIT SOUNDINGS SUGGEST THIS
WARMER AIR REACHING THE SURFACE BY EARLY AFTERNOON. THE RAP AND NAM
BUFKIT SOUNDINGS ARE SLOWER (NOT UNTIL 4-5 PM) BUT ALSO SUGGEST
WARMER TEMPS AT THE SURFACE. HOWEVER...HAVING A DIFFICULT TIME
IDENTIFYING A MECHANISM TO DRAW THIS WARM AIR TO THE SURFACE. NOT
COUNTING ON ANY HEATING AS EXPECT OVERCAST SKIES ALL DAY WITH
CEILINGS ACTUALLY LOWERING LATER TODAY WITH PATCHES OF DRIZZLE/VERY
LIGHT RAIN DEVELOPING AS SLY FLOW ALOFT STRENGTHENS.

FOR NOW...HAVE ADJUSTED MAX TEMPS UP 2-3 DEGREES MOST LOCATIONS
EXCLUDING THE NW PIEDMONT/TRIAD WHERE RESIDUAL PIEDMONT AIR MASSES
HAVE A TENDENCY TO HANG ON. STILL APPEARS A LIKELIHOOD WE WILL SEE
PATCHES OF DRIZZLE/LIGHT RAIN DEVELOP THIS AFTERNOON...STARTING
FIRST IN THE SOUTHERN PIEDMONT THEN SPREAD NWD. MAY ALSO SEE FOG
DEVELOP TOWARD SUNSET WHICH MAY BE LOCALLY DENSE.

TONIGHT....WIDESPREAD FOG AND LOW CLOUDS ANTICIPATED WITH
POSSIBILITY OF DENSE FOG A REAL CONCERN. TEMPS WILL LIKELY HOLD
STEADY IN THE 40S.

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 230 AM MONDAY...

TUESDAY: ON TUESDAY THE SURFACE HIGH CONTINUES TO MOVE SOUTHEASTWARD
OFF THE SOUTH CAROLINA COAST. WITH A LOW PRESSURE SYSTEM AND
ASSOCIATED COLD FRONT APPROACHING FROM THE WEST...CENTRAL NORTH
CAROLINA WILL BE IN THE MIDDLE OF A WARM AIR ADVECTION REGIME WHICH
WILL INCREASE IN STRENGTH AS THE DAY GOES ON. EXPECT TEMPERATURES
DRAMATICALLY HIGHER ON TUESDAY WITH MID 60S NORTHWEST TO NEAR 70 IN
THE SOUTHEAST. EXPECT SOME THINNING OF CLOUDS IN THE AFTERNOON BUT
OVERALL SHOULD REMAIN PARTLY TO MOSTLY CLOUDY IF NOT OVERCAST.
DESPITE THE CLOUDS CENTRAL NC SHOULD REMAIN DRY ON TUESDAY.-ELLIS

TUE NIGHT THROUGH WED NIGHT: A PROGRESSIVE PATTERN ALOFT WILL BE IN
TRANSITION DURING THE MIDDLE OF THE WEEK AS A HIGHLY AMPLIFIED
TROUGH ALOFT COMPRISED OF S/W ENERGY MIGRATES FROM THE FRONT RANGE
OF THE ROCKIES TO THE EAST COAST. THIS TROUGH WILL DRIVE A STRONG
FRONTAL ZONE...ONE FED BY STRONG MOISTURE TRANSPORT OFF THE GOM --
CHARACTERIZED BY PRECIPITABLE WATER VALUES AROUND 1.5 INCHES OR 2-3
SIGMAS ABOVE AVERAGE -- THROUGH CENTRAL NC WED EVENING. WARM AND
BREEZY SOUTHWESTERLY FLOW IN ADVANCE OF THE FRONT WILL SEND
TEMPERATURES INTO THE UPPER 60S WEST TO MIDDLE 70S EAST.

WIDESPREAD SOAKING SHOWERS WILL ACCOMPANY THE FRONTAL ZONE...WITH
PRECIPITATION AMOUNTS EXPECTED TO RANGE BETWEEN A HALF INCH AND ONE
INCH...HIGHEST OVER THE WESTERN PIEDMONT...WHERE FORCING FOR ASCENT
WILL BE MAXIMIZED BY THE LIFTING SOUTHERN PORTION OF THE TROUGH
ALOFT. WHILE DEEP AND LOW LEVEL SHEAR WILL BE QUITE STRONG...WEAK
LAPSE RATES ALOFT SUGGEST INSTABILITY WILL BE WEAK TO ABSENT...SO
FORCING FOR ASCENT WILL NEED TO BE SUFFICIENTLY STRONG AND
CONCENTRATED TO SUPPORT A STRONGLY FORCED/SHALLOW CONVECTIVE LINE
ALONG THE FRONT. EVEN IF THAT WERE TO OCCUR...THE CONVECTIVE LINE
WOULD BE DEVOID OF LIGHTNING...SO THUNDER WILL BE KEPT OUT OF THE
FORECAST. HOWEVER...MOMENTUM TRANSPORT FROM BOWING LINE SEGMENTS
WOULD BE CAPABLE OF PRODUCING 40-60 KT WIND GUSTS. ANY TORNADIC
POTENTIAL WILL BE LOW..DESPITE FAVORABLE SHEAR PROFILES...OWING TO
EH LACK OF INSTABILITY. HAVE SLOWED THE ARRIVAL AND DEPARTURE OF THE
SHOWERS BY ABOUT SIX HOURS IN THE GRIDDED/TEXT FORECAST...CENTERED
DURING THE EVENING HOURS.

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 335 AM MONDAY...

STRONG CAA BEHIND THE FRONT WILL RESULT IN TEMPERATURES THU ABOUT 20
DEGREES COOLER THAN THOSE OF WED. ANOTHER ARCTIC HIGH WILL HEAD
TOWARD OUR REGION FRI-SAT...LED SOUTHEASTWARD BY A CLIPPER-TYPE WAVE
AND ACCOMPANYING SURFACE COLD FRONT ON FRI. MODEL CROSS SECTIONS
INDICATE SUFFICIENT LIFT AND SATURATION TO GENERATE SNOW FROM THE
NORTHERN NC PIEDMONT NORTHWARD THROUGH VA...BUT A DEEP AND DRY
SUB-CLOUD LAYER SHOULD RESULT IN ONLY VIRGA OR A FEW
FLURRIES/SPRINKLES NORTH OF HIGHWAY 64 FRI MORNING THROUGH EARLY
AFTERNOON...SLIGHTLY LATER THAN EARLIER PROJECTIONS. OPPOSED BY
STRONG CAA AND A BRISK NORTHWESTERLY WIND ON FRI...TEMPERATURES WILL
STRUGGLE TO REACH 40 DEGREES ACROSS THE NORTHERN PIEDMONT...TO UPPER
40S TOWARD THE SC LINE. THE CENTER OF THE HIGH WILL DRIFT OVERHEAD
BY SAT MORNING...WHICH SUGGESTS EXCELLENT RADIATIONAL COOLING WILL
BE LIKELY...HINDERED ONLY BY CIRRUS ASSOCIATED WITH ANOTHER
DISTURBANCE IN NW FLOW ALOFT. PROJECTED LOW LEVEL THICKNESS VALUES
AROUND 1370 METERS SAT MORNING SUGGEST LOWS IN THE UPPER TEENS TO
LOWER 20S...WITH HIGHS IN THE LOWER TO MIDDLE 40S ON SAT. ANOTHER
CLIPPER-TYPE LOW WILL CROSS THE MIDDLE ATLANTIC SAT NIGHT...BEFORE
DEEPENING OFF THE NEW ENGLAND COAST ON SUN. ASSOCIATED PRECIPITATION
IS ACCORDINGLY EXPECTED TO OCCUR UPWIND OF THE NC BLUE RIDGE...AND
NORTH OF THE VA STATE LINE.

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 1220 PM MONDAY...

WIDESPREAD MVFR CEILINGS WILL PERSIST THIS AFTERNOON THEN LOWER INTO
THE IFR/LIFR RANGE THIS EVENING AS SLY FLOW BRINGS GULF MOISTURE
INTO THE REGION. THESE LOW CEILINGS ALONG WITH AREAS OF MVFR/IFR FOG
AND DRIZZLE WILL CREATE ADVERSE AVIATION WEATHER CONDITIONS ACROSS
CENTRAL NC THROUGH THE NIGHT INTO TUESDAY MORNING.

THE LOW CLOUDS WILL GRADUALLY LIFT AND DISSIPATE TUESDAY
MORNING...LEADING TO VFR CONDITIONS AND SCATTERED CLOUD BASES
BETWEEN 3000-4000 FT IN THE AFTERNOON. A FEW RAIN SHOWERS MAY SKIRT
THE TRIAD TERMINALS LATE IN THE DAY.

TUESDAY NIGHT...ANOTHER ROUND OF LOW CLOUDS ANTICIPATED WITH
CEILINGS AGAIN THE IFR/LIFR CATEGORIES. ANY RAIN SHOWERS THAT OCCUR
WILL BE CONFINED TO AREAS NEAR THE TRIAD TERMINALS AND BE
ISOLATED.

WINDY CONDITIONS EXPECTED WEDNESDAY AHEAD OF A STRONG COLD FRONT
THAT WILL CROSS THE AREA WEDNESDAY NIGHT. AHEAD OF THIS
FRONT...EXPECT WIDESPREAD SHOWERS AND ISOLATED T-STORMS TO
OCCUR...MAINLY LATE WEDNESDAY AFTERNOON INTO WEDNESDAY EVENING. WIND
GUSTS 30-40 MPH MAY OCCUR AHEAD OF THE FRONT.

SHARPLY COLDER TEMPERATURES EXPECTED THURSDAY INTO SATURDAY WITH VFR
CONDITIONS EXPECTED.

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

$$
SYNOPSIS...SEC
NEAR TERM...WSS
SHORT TERM...ELLIS/MWS
LONG TERM...MWS
AVIATION...WSS

AREA FORECAST DISCUSSION

NWS RALEIGH NC

930 AM EST MON JAN 28 2013

.SYNOPSIS...
WARM AND MOIST SOUTHWESTERLY FLOW WILL RIDE ATOP A LINGERING RIDGE
OF COOL SURFACE HIGH PRESSURE OVER THE CAROLINAS THROUGH TONIGHT.
THE WARM SOUTHWESTERLY FLOW WILL REACH THE SURFACE BY TUESDAY
AFTERNOON...AND CONTINUE THROUGH WEDNESDAY...IN ADVANCE OF A STRONG
COLD FRONT THAT WILL CROSS THE MIDDLE ATLANTIC AND CAROLINAS
WEDNESDAY EVENING.

.NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM MONDAY...

MONDAY AND MONDAY NIGHT:

MID MORNING TEMPS HAVE WARMED INTO THE MID AND UPPER 30S ACROSS
CENTRAL NC. THUS...FZRA THREAT ACROSS THE FAR NORTH HAS ENDED AND
THE ADVISORY ALLOWED TO EXPIRE.

NEXT FORECAST CHALLENGE IS MAX TEMPS FOR TODAY. NEAR TERM MODEL
GUIDANCE SUGGEST MAX TEMPS A GOOD 4-5 DEGREES WARMER THAN CURRENT
FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT INTO THE NORTHERN
COASTAL PLAIN. 12Z GSO SOUNDING INDICATE AS THICK LAYER OF WARM AIR
JUST 500-1000FT OFF THE SURFACE. GFS BUFKIT SOUNDINGS SUGGEST THIS
WARMER AIR REACHING THE SURFACE BY EARLY AFTERNOON. THE RAP AND NAM
BUFKIT SOUNDINGS ARE SLOWER (NOT UNTIL 4-5 PM) BUT ALSO SUGGEST
WARMER TEMPS AT THE SURFACE. HOWEVER...HAVING A DIFFICULT TIME
IDENTIFYING A MECHANISM TO DRAW THIS WARM AIR TO THE SURFACE. NOT
COUNTING ON ANY HEATING AS EXPECT OVERCAST SKIES ALL DAY WITH
CEILINGS ACTUALLY LOWERING LATER TODAY WITH PATCHES OF DRIZZLE/VERY
LIGHT RAIN DEVELOPING AS SLY FLOW ALOFT STRENGTHENS.

TONIGHT....WIDESPREAD FOG AND LOW CLOUDS ANTICIPATED WITH
POSSIBILITY OF DENSE FOG A REAL CONCERN. TEMPS WILL LIKELY HOLD
STEADY IN THE 40S.

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 230 AM MONDAY...

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 335 AM MONDAY...

.AVIATION /13Z MONDAY THROUGH FRIDAY/...
AS OF 630 AM MONDAY...

24 HOUR TAF PERIOD:

PATCHY LIGHT RAIN OR DRIZZLE WILL CONTINUE AT MOST LOCATIONS THIS
MORNING WITH KINT AND KGSO ENDING WITHIN THE HOUR. KFAY COULD SEE
SOME LIGHT DRIZZLE BUT KRDU AND KRWI WILL SEE THE MOST PRECIPITATION
THIS MORNING. WITH TEMPERATURES RIGHT AROUND FREEZING...FREEZING
RAIN IS STILL NOT OUT OF THE QUESTION...MOST LIKELY AT KRWI.
OTHERWISE LIGHT SOUTHERLY TO SOUTHWESTERLY FLOW WILL TAKE OVER
TODAY. SOME MVFR/IFR CEILINGS OUT THERE THIS MORNING SHOULD LIFT TO
VFR EARLY THIS AFTERNOON...HOWEVER CLOUD COVER WILL CONTINUE THIS
AFTERNOON WITH CEILINGS AGAIN DETERIORATING LATE THIS AFTERNOON INTO
THE EVENING. WHILE CONDITIONS ARE FAVORABLE FOR WIDESPREAD FOG
OVERNIGHT MONDAY INTO TUESDAY...SOME HIGHER WIND SPEEDS COULD CREATE
MORE OF A LOW STRATUS SITUATION WITH LIFR CEILINGS EXPECTED
EVERYWHERE. VISIBILITIES MAY COME DOWN VARYING AMOUNTS BUT THAT WONT
MATTER GIVEN CIGS ARE EXPECTED TO FALL TO LIFR.

LOOKING AHEAD:

FOG AND OR LOW STRATUS WILL BE LIKELY TUESDAY
MORNING. ADVERSE CONDITIONS ARE ALSO LIKELY WEDNESDAY INTO THURSDAY
WITH THE PASSAGE OF A FRONTAL SYSTEM. ON FRIDAY...NORTHERN SITES MAY
HAVE A CHANCE FOR SOME LIGHT SNOW SHOWERS.

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

$$
SYNOPSIS...MWS
NEAR TERM...WSS
SHORT TERM...ELLIS/MWS
LONG TERM...MWS
AVIATION...ELLIS

AREA FORECAST DISCUSSION

NWS RALEIGH NC

727 AM EST MON JAN 28 2013

.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 AM MONDAY...

MONDAY AND MONDAY NIGHT:

FREEZING RAIN ADVISORY EXTENDED TO INCLUDE COUNTIES IN THE
NORTHEASTERN PIEDMONT OF NC THROUGH 9AM...

HAVE EXTENDED THE FREEZING RAIN ADVISORY THROUGH THE NORTHEASTERN
COUNTIES BASED ON THE FACT THAT BOTH CURRENT TEMPERATURES AND WET
BULB TEMPERATURES REMAIN BELOW FREEZING IN THIS AREA...ALONG THE
AXIS OF THE DRY AIR SURFACE RIDGE...AND SINCE CURRENT RADAR TRENDS
AND CURRENT RUNS OF THE RAP/RUC MODEL SHOW THE AREA OF PRECIPITATION
EXPANDING FROM THE COASTAL PLAIN TO THE WEST OF THE TRIAD WILL
CONTINUE EASTWARD ACROSS THE CWA IMPACTING THE NORTHEASTERN COUNTIES
THROUGH 9 AM.

CURRENT SURFACE ANALYSIS SHOWS SURFACE HIGH PRESSURE SET UP OVER THE
TIDEWATER VIRGINIA REGION. THIS HIGH IS RESPONSIBLE FOR SUBFREEZING
TEMPERATURES IN EASTERN NORTH CAROLINA WITH NORTHEASTERLY FLOW.
FURTHER WEST HOWEVER...RETURN FLOW AROUND THE HIGH HAS KEPT
TEMPERATURES MAINLY IN THE MIDDLE 30S. CURRENT RADAR TRENDS SHOW
REFLECTIVITIES SPLITTING WITH ONE AREA MOVING SWIFTLY ACROSS THE
NORTHERN TIER OF THE CWA WITH ANOTHER BAND TO THE SOUTH. THE
OCCURRENCE OF FREEZING RAIN IS VERY QUESTIONABLE AT THIS POINT DUE
TO A COUPLE OF FACTORS. CLOUD COVER AND SOUTHERLY FLOW IN THE WEST
HAVE KEPT TEMPERATURES UP. WHILE SOME LIGHT RAIN OR DRIZZLE MAY BE
LIKELY...FREEZING RAIN IS NOT AS LIKELY UNLESS ENOUGH WETBULBING
OCCURS TO BRING TEMPERATURES BACK DOWN TO FREEZING. FURTHER TO THE
EAST...TEMPERATURES HAVE ALREADY ACHIEVED THE FREEZING MARK BUT AS
THE HIGH SLIDES EASTWARD ALONG WITH IT WILL COME THE CLOUDS AND
SOUTHERLY FLOW AND A RISE IN THE SURFACE TEMPERATURES. AT THIS POINT
THE MOST LIKELY AREA FOR FREEZING RAIN WILL BE THE NORTHEAST BECAUSE
EVEN IF TEMPERATURES RISE BACK ABOVE FREEZING...ONCE PRECIPITATION
STARTS WETBULBING SHOULD BRING IT BACK DOWN. WITH A NORTH TO SOUTH
ORIENTED BAND MOVING ACROSS THE NORTH...ANY PRECIPITATION THAT DOES
OCCUR SHOULD ONLY LAST AN HOUR OR TWO MAXIMUM. IT IS LIKELY THAT THE
FREEZING RAIN ADVISORY WILL HAVE TO BE TRIMMED BACK FROM WEST TO
EAST OR PERHAPS CANCELLED ALL TOGETHER AS CONDITIONS WARRANT.
CURRENT RAP SOUNDINGS INDICATE THAT MANY SITES WILL REMAIN ABOVE
FREEZING WITH THE EXCEPTION OF THOSE IN THE FAR EASTERN PORTIONS OF
THE AREA. WHETHER OR NOT PRECIPITATION ARRIVES IN TIME TO TAKE
ADVANTAGE OF THOSE LOWER TEMPERATURES REMAINS TO BE SEEN.
REGARDLESS...EXPECT PATCHY SPRINKLES OR LIGHT RAIN THROUGH SUNRISE
WITH ISOLATED PATCHES OF FREEZING RAIN MOST LIKELY IN THE NORTHEAST.
MINIMUM TEMPERATURES HAVE ALREADY BOTTOMED OUT IN MOST CASES MID TO
UPPER 20S EAST AND LOWER 30S WEST.

ANY ONGOING PRECIPITATION SHOULD TAPER OFF MONDAY MORNING WITH A
SOME FOG POSSIBLE IN LOCALIZED AREAS. SKIES WILL REMAIN OVERCAST FOR
MOST OF THE DAY ON MONDAY. COMBINING THIS ALONG WITH AFTERNOON
THICKNESS VALUES IN THE MID 1300S SHOULD KEEP MAXIMUM TEMPERATURES
DOWN ON MONDAY...MID 40S NORTHWEST TO UPPER 40S TO LOWER 50S IN THE
SOUTHEAST. SOME LIGHT RAIN OR DRIZZLE IS POSSIBLE THROUGHOUT MUCH OF
THE DAY ON MONDAY. CEILINGS WILL GRADUALLY COME DOWN MOST LIKELY TO
IFR/LIFR LATER MONDAY NIGHT INTO TUESDAY MORNING. WITH BOTH
TEMPERATURES AND DEWPOINTS IN THE MID 40S TUESDAY NIGHT...CONDITIONS
ARE FAVORABLE FOR A WIDESPREAD FOG EVENT. FORECAST SOUNDINGS ARE
HINTING AT THIS PROBABILITY AND WILL CONTINUE TO MONITOR THE
SITUATION FOR A POSSIBLE DENSE FOG ADVISORY MONDAY NIGHT INTO
TUESDAY MORNING.

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 230 AM MONDAY...

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 335 AM MONDAY...

.AVIATION /13Z MONDAY THROUGH FRIDAY/...
AS OF 630 AM MONDAY...

24 HOUR TAF PERIOD:

LOOKING AHEAD:

.RAH WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR
NCZ007>011-024>028-041-043.

$$
SYNOPSIS...MWS
NEAR TERM...ELLIS
SHORT TERM...ELLIS/MWS
LONG TERM...MWS
AVIATION...ELLIS

AREA FORECAST DISCUSSION

NWS RALEIGH NC

632 AM EST MON JAN 28 2013

.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 AM MONDAY...

MONDAY AND MONDAY NIGHT:

...FREEZING RAIN ADVISORY EXTENDED TO INCLUDE COUNTIES IN THE
NORTHEASTERN PIEDMONT OF NC THROUGH 9AM...

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 230 AM MONDAY...

.LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 335 AM MONDAY...

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AS OF 630 AM MONDAY...

24 HOUR TAF PERIOD:

LOOKING AHEAD:

.RAH WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR
NCZ007>011-021>028-038>041-043.

$$
SYNOPSIS...MWS
NEAR TERM...ELLIS
SHORT TERM...ELLIS/MWS
LONG TERM...MWS
AVIATION...ELLIS

AREA FORECAST DISCUSSION

NWS RALEIGH NC

338 AM EST MON JAN 28 2013

.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 AM MONDAY...

MONDAY AND MONDAY NIGHT:

...FREEZING RAIN ADVISORY EXTENDED TO INCLUDE COUNTIES IN THE
NORTHEASTERN PIEDMONT OF NC THROUGH 9AM...

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 230 AM MONDAY...

.LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 335 AM MONDAY...

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
AS OF 1220 AM MONDAY...

24 HOUR TAF PERIOD:

TRICKY FORECAST OVERNIGHT TONIGHT AS RADAR CURRENTLY SHOWING LIGHT
PRECIPITATION MOVING ACROSS THE FOOTHILLS AND INTO THE WESTERN
PIEDMONT OF NORTH CAROLINA. THIS COMBINED WITH SUB FREEZING
TEMPERATURES COULD GIVE A CHANCE FOR SOME LIGHT FREEZING RAIN FROM
WEST TO EAST ACROSS THE AREA. WHILE THERE IS A CHANCE THAT KINT AND
KGSO COULD GET SOME LIGHT RAIN BETWEEN 6 AND 8Z...CLOUD COVER HAS
KEPT TEMPERATURES IN THE MID 30S. IN ADDITION THE HEAVIER RETURNS ON
THE RADAR HAVE BEGUN TO MOVE SOUTH OF KINT AND KGSO AND THEREFORE
ONLY A THIN BAND OF PRECIPITATION ORIENTED NORTH TO SOUTH WILL CROSS
THE AREA...MOST LIKELY WITH TEMPERATURES ABOVE FREEZING. FURTHER
EAST WHERE THERE IS LESS CLOUD COVER TEMPERATURES HAVE ALREADY
DIPPED TOWARDS THE FREEZING MARK WITH KRDU AND KFAY ON THE VERGE OF
FREEZING AND KRWI ALREADY REPORTING 26 DEGREES. WITH RETURNS MOVING
TO THE SOUTH...THERE IS A GROWING CHANCE OF SOME FREEZING RAIN AT
KFAY...BUT THE ONSET OF OVERCAST SKIES HAS ELEVATED THE TEMPERATURE
IN THE LAST COUPLE OF HOURS. SAME IS TRUE FOR KRDU. WILL COVER ALL
FREEZING RAIN WITH TEMPO GROUPS IN THE TAF AND HAVE LEFT IT OUT OF
KRWI AT THIS TIME BECAUSE OF WEAKENING RADAR TRENDS. OTHERWISE
EXPECT LIGHT SOUTHWESTERLY FLOW WITH CEILING GRADUALLY COMING DOWN
THROUGHOUT THE TAF PERIOD WITH MVFR AND IFR CEILINGS LIKELY BY EARLY
TUESDAY MORNING.

LOOKING AHEAD:

.RAH WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR
NCZ007>011-021>028-038>041-043.

$$
SYNOPSIS...MWS
NEAR TERM...ELLIS
SHORT TERM...ELLIS/MWS
LONG TERM...MWS
AVIATION...ELLIS

AREA FORECAST DISCUSSION

NWS RALEIGH NC

332 AM EST MON JAN 28 2013

.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 AM MONDAY...

MONDAY AND MONDAY NIGHT:

...FREEZING RAIN ADVISORY EXTENDED TO INCLUDE COUNTIES IN THE
NORTHEASTERN PIEDMONT OF NC THROUGH 9AM...

HAVE EXTENDED THE FREEZING RAIN ADVISORY THROUGH THE NORTHEASTERN
COUNTIES BASED ON THE FACT THAT CURRENT TEMPERATURES REMAIN BELOW
FREEZING AND SURFACE WETBULBS CONTINUE TO BE BELOW ZERO IN THIS
AREA. CURRENT RADAR TRENDS AND CURRENT RUN OF THE RAP/RUC MODEL
SHOW AREA OF PRECIPITATION CURRENTLY ENTERING THE TRIAD TO
CONTINUE EASTWARD ACROSS THE CWA IMPACTING THE NORTHEASTERN
COUNTIES SOMETIME BETWEEN 6 AND 9AM.

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 230 AM MONDAY...

TUESDAY NIGHT: THE MSLP GRADIENT TIGHTENS TUESDAY NIGHT OVER NC WITH
THE GROWING CONTRAST BETWEEN THE OFFSHORE HIGH AND INCOMING COLD
FRONT. LOW LEVEL WARM AIR ADVECTION AND CLOUDS WILL TRANSLATE INTO
MILD PREFRONTAL LOWS... AND HAVE RAISED THEM SEVERAL DEGREES TO
54-61. EXPECT PATCHY LIGHT SHOWERS TO DEVELOP OVERNIGHT MAINLY IN
THE WEST WITH INCREASING PRECIP WATER TO OVER 1 INCH AND DEEPENING
MOIST UPGLIDE.

FOR WEDNESDAY/WEDNESDAY NIGHT: WINDY/WET/WARM FOLLOWED BY A STARK
COOLDOWN. THE RECENT NAM RUNS HAVE TRENDED MUCH FASTER WITH THE
INCOMING FRONT AND ASSOCIATED WARM-CONVEYOR BAND OF SHOWERS... WHILE
THE MORE CONSISTENT GFS HAS SHOWN JUST A SLIGHT SLOWING TREND AND
AGREES WITH THE ECMWF TIMING. CONSENSUS OF THE GFS/ECMWF BRINGS IN
JUST LIGHT SCATTERED SHOWERS THROUGH WEDNESDAY MORNING... WITH THE
MORE NUMEROUS AND HEAVIER SHOWERS ARRIVING IN THE AFTERNOON THROUGH
EVENING SWEEPING WEST TO EAST. PRECIP WATER VALUES ARE EXPECTED TO
EXCEED 1.5 INCHES... HIGHLY ANOMALOUS FOR LATE JANUARY (IN THE 99TH
PERCENTILE)... AND FORECAST SOUNDINGS DEPICT A DEEP WARM LAYER (LCL
TO FREEZING OF 3.0-3.2 KM)... THUS HEAVY DOWNPOURS ARE POSSIBLE.
HAVE RAISED POPS TO CATEGORICAL... FOCUSING AFTER 18Z IN THE
PIEDMONT/WRN SANDHILLS AND AFTER 23Z IN THE ERN SANDHILLS AND
COASTAL PLAIN. THE VERTICAL PROFILE BECOMES NEARLY MOIST ADIABATIC
AT BEST... AND WITH THE MARGINAL LAPSE RATES AND LACK OF INSTABILITY
IN THE MIXED PHASE REGION ALOFT... WILL NOT INCLUDE THUNDER AT THIS
TIME DUE TO ITS EXPECTED SPARSITY BUT THIS MAY NEED TO BE ADDED TO
LATER FORECASTS. DESPITE THE LACK OF DOWNWARD MOMENTUM THE BOUNDARY
LAYER WINDS ALONE FAVOR QUITE A WINDY DAY... SUSTAINED 15-20 MPH
GUSTING TO AROUND 30 MPH... AND WOULD NOT BE AT ALL SURPRISED TO SEE
THESE NUMBERS COME UP A BIT IN LATER FORECASTS TOO... ONCE WE CAN
OBSERVE UPSTREAM PREFRONTAL CONDITIONS. EVEN WITH THE MODERATE TO
HEAVY SHOWERS... WE SHOULD SEE STORM TOTAL QPF AMOUNTS OF A THIRD TO
HALF INCH... LIMITED BY THE SPEED OF THIS SYSTEM. HIGHS FROM 64 NW
TO 76 SE. LOWS 36-46 WITH THE FRONT SHIFTING OFF THE COAST AFTER
MIDNIGHT... AND SKIES CLEARING LATE. -GIH

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 225 PM SUNDAY...

FOR THURSDAY THROUGH FRIDAY: THE DAMPENING LONGWAVE TROUGH AXIS WILL
BE HEADING EASTWARD OFF THE COAST THURSDAY MORNING... ALTHOUGH EYES
THEN TURN TO A STRONG MID LEVEL SHORTWAVE TROUGH DROPPING SOUTHWARD
INTO THE UPPER MIDWEST EARLY THURSDAY... POISED TO SWING THROUGH THE
MIDATLANTIC REGION ON FRIDAY. LOW LEVEL THICKNESSES PLUNGE FROM LATE
WEDNESDAY INTO THURSDAY MORNING... FROM 55-60 METERS ABOVE NORMAL
DOWN TO NEAR OR JUST UNDER NORMAL AS MODIFIED HIGH PRESSURE BUILDS
EASTWARD OVER THE GULF COAST. WE SHOULD STAY A LITTLE BREEZY THROUGH
EARLY THURSDAY. HIGHS 44-55 WITH MOSTLY SUNNY SKIES. EXPECT
INCREASING MID AND HIGH CLOUDS THURSDAY NIGHT AS THE ALREADY-SWIFT
UPPER LEVEL FLOW STRENGTHENS ANEW TO 140+ KTS IN RESPONSE TO THE
APPROACHING ENERGY ALOFT. LOWS IN THE LOWER 30S. AS ONE MIGHT EXPECT
AT THIS RANGE... THE GFS/ECMWF DIFFER A BIT WITH REGARDS TO TIMING
AND STRENGTH OF THE VORTICITY MAXIMUM THAT CROSSES THE AREA
FRIDAY... BUT THIS PATTERN WITH DECENT DYNAMIC FORCING... COLD AIR
IN PLACE... AND BACKING LOW LEVEL WINDS ALLOWING A TRANSPORT OF
MOISTURE... DOES SUPPORT AT LEAST A SMALL CHANCE OF A QUICK SNOW
SHOWER... AND IF THE ECMWF`S STRONGER WAVE IS CORRECT... SCATTERED
COVERAGE COULD BE ACHIEVED. WILL PLACE A SLIGHT CHANCE OF A SNOW
SHOWER ALONG/NORTH OF HIGHWAY 64. WITH THICKNESSES FRIDAY RUNNING 20
METER BELOW NORMAL AND SCATTERED TO BROKEN COLD AIR CONVECTIVE
CLOUDS... EXPECT HIGHS OF JUST 36-40 IN THE NORTH AND 40-46
SOUTHEAST.

FOR FRIDAY NIGHT THROUGH SUNDAY: AS A YUKON-SOURCE HIGH BUILDS
OVERHEAD FROM THE NNW WITH THE POLAR WESTERLIES EXTENDING WELL DOWN
TO OUR LATITUDE... EXPECT FAIR TO PARTLY CLOUDY SKIES AND CHILLY
TEMPS FRIDAY NIGHT INTO SATURDAY. ANOTHER MID LEVEL WAVE SWINGING
THROUGH THE MIDATLANTIC AND NORTHEAST SATURDAY AFTERNOON/NIGHT WILL
BRING ANOTHER CLIPPER FRONT THROUGH THE REGION... REINFORCING THE
BELOW-NORMAL TEMPS. NO POPS FOR THIS TIME FRAME YET BUT ANOTHER
ROUND OF ISOLATED SNOW SHOWERS FOR THE NORTHERN BORDER COUNTIES IS
CERTAINLY POSSIBLE EARLY SUNDAY. LOWS IN THE 20S AND HIGHS IN THE
LOW-MID 40S. -GIH

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
AS OF 1220 AM MONDAY...

24 HOUR TAF PERIOD:

LOOKING AHEAD:

.RAH WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR
NCZ007>011-021>028-038>041-043.

$$
SYNOPSIS...MWS
NEAR TERM...ELLIS
SHORT TERM...ELLIS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...ELLIS

AREA FORECAST DISCUSSION

NWS RALEIGH NC

237 AM EST MON JAN 28 2013

.SYNOPSIS...

WARM AND MOIST SOUTHWESTERLY FLOW WILL RIDE ATOP A LINGERING RIDGE
OF COOL SURFACE HIGH PRESSURE OVER THE CAROLINAS THROUGH TONIGHT.
THE WARM SOUTHWESTERLY FLOW WILL REACH THE SURFACE BY TUESDAY
AFTERNOON...AND CONTINUE THROUGH WEDNESDAY...IN ADVANCE OF A STRONG
COLD FRONT THAT WILL CROSS THE MIDDLE ATLANTIC AND CAROLINAS
WEDNESDAY EVENING.

.NEAR TERM /THROUGH MONDAY NIGHT/...
AS OF 230 AM MONDAY...

MONDAY AND MONDAY NIGHT:

...FREEZING RAIN ADVISORY REMAINS IN EFFECT THROUGH 9AM FOR THE
NORTHERN PIEDMONT...

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 230 AM MONDAY...

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 225 PM SUNDAY...

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 1220 AM MONDAY...

24 HOUR TAF PERIOD:

LOOKING AHEAD:

.RAH WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY FROM 9 PM THIS EVENING TO 9 AM EST MONDAY FOR
NCZ007>010-021>026-038>041.

SYNOPSIS...MWS
NEAR TERM...ELLIS
SHORT TERM...ELLIS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...ELLIS

AREA FORECAST DISCUSSION

NWS RALEIGH NC

1223 AM EST MON JAN 28 2013

.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL CROSS THE REGION TONIGHT THROUGH
MONDAY MORNING. DEVELOPING SOUTH TO SOUTHWEST FLOW WILL BRING WARMER
TEMPERATURES TO CENTRAL NORTH CAROLINA TUESDAY AND WEDNESDAY WITH A
SHOWERS LIKELY AHEAD OF A STRONG COLD FRONT WEDNESDAY AFTERNOON AND
WEDNESDAY NIGHT.

.NEAR TERM /TONIGHT THROUGH MONDAY/...
AS OF 930 PM SUNDAY...

NO CHANGE TO THE FREEZING RAIN ADVISORY TONIGHT. LIGHT PRECIP ON
THE EASTERN FRINGES OF A WARM FRONT MOVING INTO THE OH VALLEY IS
NOW MOVING INTO NORTHEAST TN....THOUGH WITH A LIMITED NUMBER OF
SITES REPORTING MEASURABLE PRECIP. THE 00Z KGSO RAOB CAME IN PRETTY
MUCH IN TUNE WITH FORECAST SOUNDINGS...SHOWING A SIGNIFICANT DRY
LAYER BETWEEN 850MB AND 600MB...COINCIDENT WITH THE LOW/MID LEVEL
RIDGE AXIS OVER THE SOUTHEAST US. THE HRRR 1KM REFLECTIVITY
FORECAST CONTINUES TO EXPAND PRECIP SOUTHEAST INTO THE PIEDMONT AND
NORTHERN COASTAL PLAIN TONIGHT BETWEEN 1AM AND 8AM. HOWEVER...RAP
SOUNDINGS NEVER QUITE SHOW SATURATION BELOW 1KM...SO IT REMAINS
QUESTIONABLE WEATHER THERE WILL BE ENOUGH ISENTROPIC LIFT AND
MOISTURE TO SUFFICIENTLY OVERCOME THE DRY AIR BELOW 10K FT.
THUS..UNCERTAINTY IN THE FORECAST IS BASED AROUND MOISTURE AND
PRECIP.

TEMPERATURES HAVE DROPPED RAPIDLY BELOW FREEZING IN AREAS EAST OF US
HWY 1 WHERE MID LEVEL CLOUD COVER HAS YET TO MOVE IN. WEST OF US
HWY 1...TEMPS ARE HOLDING IN THE MID TO UPPER 30S...AND THERE IS THE
POTENTIAL THEY THEY MAY ONLY FALL TO AT OR JUST ABOVE FREEZING WITH
SURFACE WETBULB TEMPS ALREADY ESSENTIALLY AT 30 OR ABOVE.

BASED ON THIS...CONFIDENCE IN FREEZING RAIN IS HIGHEST NORTH OF THE
TRIANGLE INTO THE NORTHERN COASTAL PLAIN...GENERALLY FROM CHAPEL
HILL/DURHAM TO LOUISBURG...WARRENTON AND POTENTIALLY AS FAR EAST AS
ROANOKE RAPIDS. HALIFAX COUNTY IS NOT CURRENTLY IN THE ADVISORY AND
BASED ON COORDINATION OF NEIGHBORING OFFICES...WILL HOLD OFF ON
ADDING TO THE ADVISORY UNTIL WE GET A BETTER SENSE OF HOW THE PRECIP
IS EVOLVING. WE STILL EXPECT THE RAIN/FREEZING RAIN TO BE PATCHY
AND LIGHT...JUST A TRACE TO A FEW HUNDREDTHS IN MOST LOCATIONS.
-SMITH

MONDAY...FIRST AREA OF PRECIP EXITS THE NORTHERN SECTIONS EARLY IN
THE MORNING. INCREASING LOW LEVEL SLY WILL MAINTAIN LOW CLOUDS
THROUGH THE DAY WITH SPOTS OF DRIZZLE OR LIGHT RAIN POSSIBLE. STILL
CHILLY WITH TEMPS IN THE 40S FAR NORTH TO THE LOW AND POSSIBLY MID
50S FAR SOUTH-SOUTHEAST.

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 110 PM SUNDAY...

FOR MONDAY NIGHT: THE LOW LEVEL FLOW SHOULD VEER A BIT SO AS TO
GREATLY DIMINISH THE LOW LEVEL MOIST UPGLIDE... BUT THE COMBINATION
OF EARLY-NIGHT GROUND COOLING RESULTING IN LOW LEVEL STABILIZATION
(REINFORCED BY STRENGTHENING WARM AIR ADVECTION AT 950-850 MB) AND
MOISTENING SHOULD RESULT IN WIDESPREAD THICK STRATUS AND FOG WITHIN
THE RESIDUAL STABLE POOL OVER ALL OF CENTRAL NC STARTING IN THE
EARLY EVENING... ALONG WITH PATCHES OF VERY LIGHT DRIZZLE IN THE NRN
PIEDMONT BENEATH THE TAIL OF THE EXITING LOW LEVEL JET. WITH A
SLOWLY MODIFYING AIR MASS AND CLOUDS BLANKETING THE AREA... EXPECT
LOWS TO BE MINIMALLY LOWER THAN MONDAY HIGHS... 40-47.

FOR TUESDAY/TUESDAY NIGHT: THE RELATIVE CALM BEFORE THE STORM. THE
OFFSHORE PARENT SURFACE HIGH WILL NOSE WESTWARD THROUGH THE
SOUTHEAST AND CAROLINAS WHILE HEIGHTS STEADILY RISE ALONG THE
EASTERN SEABOARD IN RESPONSE TO THE APPROACH LONGWAVE TROUGH. LOW
LEVEL MOISTURE REMAINS ABUNDANT HOWEVER ESPECIALLY IN WRN NC THROUGH
THE WRN PIEDMONT... AND FORECAST SOUNDINGS INDICATE THAT THE LOW
LEVEL STABLE LAYER WILL BE TOUGH TO DISLODGE VIA TRADITIONAL EROSION
MECHANISMS SUCH AS VERTICAL MIXING... EDGE DISSOLUTION AND
HORIZONTAL DISPERSION... AND THIS IS REFLECTED WELL IN CURRENT
FORECAST HIGHS WHICH SUGGEST SUPPRESSED WARMTH OVER THE PIEDMONT.
WILL NOT DEPART FAR FROM THIS EARLIER FORECAST... WITH HIGHS RANGING
FROM 60 NW TO 76 SE UNDER PARTLY TO MOSTLY CLOUDY SKIES. THIS IS
STILL 10-20 DEGREES ABOVE NORMAL ACROSS THE AREA. THE MSLP GRADIENT
TIGHTENS TUESDAY NIGHT OVER NC WITH THE GROWING CONTRAST BETWEEN THE
OFFSHORE HIGH AND INCOMING COLD FRONT. LOW LEVEL WARM AIR ADVECTION
AND CLOUDS WILL TRANSLATE INTO MILD PREFRONTAL LOWS... AND HAVE
RAISED THEM SEVERAL DEGREES TO 54-61. EXPECT PATCHY LIGHT SHOWERS TO
DEVELOP OVERNIGHT MAINLY IN THE WEST WITH INCREASING PRECIP WATER TO
OVER 1 INCH AND DEEPENING MOIST UPGLIDE.

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 225 PM SUNDAY...

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 1220 AM MONDAY...

24 HOUR TAF PERIOD:

LOOKING AHEAD:

.RAH WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY FROM 9 PM THIS EVENING TO 9 AM EST MONDAY FOR
NCZ007>010-021>026-038>041.

SYNOPSIS...WSS
NEAR TERM...WSS/SMITH
SHORT TERM...HARTFIELD
LONG TERM...HARTFIELD
AVIATION...ELLIS

AREA FORECAST DISCUSSION

NWS RALEIGH NC12

1223 PM EST MON JAN 28 2013

.NEAR TERM /TONIGHT THROUGH MONDAY/...
AS OF 930 PM SUNDAY...

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 110 PM SUNDAY...

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 225 PM SUNDAY...

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 1220 AM MONDAY...

24 HOUR TAF PERIOD:

LOOKING AHEAD:

.RAH WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY FROM 9 PM THIS EVENING TO 9 AM EST MONDAY FOR
NCZ007>010-021>026-038>041.

SYNOPSIS...WSS
NEAR TERM...WSS/SMITH
SHORT TERM...HARTFIELD
LONG TERM...HARTFIELD
AVIATION...ELLIS

AREA FORECAST DISCUSSION...UPDATED

NWS GRAND FORKS ND

717 AM CST MON JAN 28 2013

.UPDATE...THE LOW CIGS AND VSBY UNDER 2 MILES HAS MOVED INTO THE
THIEF RIVER FALLS AREA. LOCAL REPORTS FROM THAT AREA INDICATE
LIGHT FREEZING DRIZZLE STARTED ABOUT AN HOUR AGO. THUS...WILL
EXPAND THE FREEZING RAIN ADVISORY INTO THIS AREA. INCOMING RAP
GUIDANCE STILL SUGGEST VSBY WILL IMPROVE BY 18Z...WHICH SHOULD
CORRESPOND TO THE FREEZING DRIZZLE ENDING. THIS MAKES SENSE
CONSIDERING SUBSIDENCE ON THE BACK SIDE OF THE DEPARTING UPPER
WAVE. SATELLITE IMAGERY CONFIRMS THIS WITH CLEARING SKY ABOUT TO
ENTER THE SOUTHWEST FA.

.AVIATION...EXPECT MVFR/IFR CONDITIONS TO AFFECT AREAS ALONG AND
EAST OF THE RED RIVER VALLEY THROUGH THE MORNING HOURS. THE
NORTHERN/WESTERN EDGE OF THESE LOW CIGS MIGHT ADVECT EASTWARD THIS
AFTERNOON...WITH VFR CONDITIONS POSSIBLY MOVING INTO KGFK/KTVF BY
LATE AFTERNOON (ALTHOUGH WILL REMAIN PESSIMISTIC IN THE TAF
FORECAST). FREEZING DRIZZLE POSSIBLE THROUGH THE MORNING
HOURS...THEN A BAND OF HEAVIER SNOW WILL MOVE INTO WEST CENTRAL
MINNESOTA LATER THIS AFTERNOON. WINDS WILL REMAIN LIGHT THROUGH
THE PERIOD.

.PREV DISCUSSION... /ISSUED 428 AM CST MON JAN 28 2013/

UPDATE...DID NOT WANT TO COMPLICATE THINGS ANY MORE...BUT GETTING
REPORTS OF FREEZING DRIZZLE ACROSS THE SOUTHERN HALF OF THE
FORECAST AREA RESULTING IN ICY ROADS. WILL NEED TO ISSUE A
FREEZING RAIN ADVISORY (FOR FREEZING DRIZZLE) THROUGH THE MORNING
HOURS. SNOW SHOWERS WILL MOVE ACROSS THE NORTHERN PART OF THIS
ADVISORY OVER THE NEXT FEW HOURS...WHICH WILL LIKELY END THE
FREEZING DRIZZLE HERE. LATEST RAP INDICATES VISIBILITY WILL
IMPROVE ACROSS THE SOUTHERN PART OF THIS ADVISORY BY NOON...WHICH
SHOULD CORRESPOND TO THE END OF THE FREEZING DRIZZLE.

PREV DISCUSSION... /ISSUED 335 AM CST MON JAN 28 2013/

SHORT TERM (TODAY-WED NIGHT)...THE MAIN CONCERN THIS PERIOD WILL
BE THE POTENTIAL OF A HEAVY SNOW BAND ACROSS THE SOUTHEAST FA. 00Z
MODELS IN DECENT AGREEMENT AND WILL USE A BLEND.

A COUPLE SHORTWAVES IN SOUTHWEST FLOW ALOFT WILL AFFECT THE
REGION TODAY. THE FIRST SHORTWAVE IS CURRENTLY (09Z) ALONG THE
SOUTH DAKOTA/NORTH DAKOTA BORDER...AND WILL CONTINUE TO PROPAGATE
NE THROUGH THE DAY. THERE IS AN AREA OF SCATTERED SNOW SHOWERS
ASSOCIATED WITH THIS FEATURE...AND WILL INCLUDE 50% POPS ACROSS
THE NORTHERN FA THIS MORNING. EXPECT FOG THROUGH THE MORNING HOURS
ACROSS THE SOUTHERN FA ASSOCIATED WITH HIGHER SURFACE MOISTURE.
THERE HAVE BEEN NO REPORTS OF FREEZING DRIZZLE...AND MOST
VISIBILITIES ARE 1/2SM OR GREATER. WILL MONITOR...BUT FOR NOW NO
HEADLINES ARE NEEDED THROUGH THE MORNING HOURS.

ATTENTION THEN TURNS TO THE NEXT SHORTWAVE THAT WILL EJECT FROM
THE WEST COAST TROUGH AND INTO THE NORTHERN PLAINS. THIS FEATURE
WILL INDUCE MID-LEVEL FRONTOGENESIS AND LEAD TO A BAND OF PRECIP
BY LATE AFTERNOON...CONTINUING INTO THE OVERNIGHT HOURS. MODELS
ARE IN GENERAL AGREEMENT WITH THE LOCATION OF THIS
BAND...GENERALLY FROM THE EXTREME SOUTHERN RED RIVER VALLEY INTO
THE PARK RAPIDS AREA (CONTINUING TO THE NORTHEAST). THE ECMWF/GFS
ARE SLIGHTLY NORTH OF THE NAM/RAP WITH PLACEMENT. THE ECMWF/GFS
SHOW 0.50-0.70 INCHES QPF WITHIN THE HEAVIEST BAND...WHILE THE
NAM/4-KM WRF SHOW 0.80-1.00 INCHES QPF WITHIN THE HEAVIEST BAND.
CONDITIONAL INSTABILITY PARAMETERS ARE FAVORABLE...SUGGESTING THAT
THE HIGHER RESOLUTION MODELS MAY BE MORE CORRECT (HIGHER QPF).
850MB TEMPS WILL BE ABOVE FREEZING AS THE PRECIP BEGINS...BUT
SHOULD QUICKLY COOL TO BELOW FREEZING. A BRIEF PERIOD OF FREEZING
RAIN WILL BE POSSIBLE BEFORE CHANGING OVER TO SNOW. SNOW RATIO
VALUES WILL BE LOW (MORE TOWARD 10:1-12:1). FINAL SNOW AMOUNTS
WILL DEPEND UPON THE DURATION OF THE FREEZING RAIN BEFORE CHANGING
TO SNOW. THE OTHER CHALLENGING ASPECT OF THESE EVENTS IS THAT THE
HEAVIEST BAND OF SNOW IS QUITE NARROW. THE POTENTIAL EXISTS FOR
6-12 INCHES WITHIN THE HEAVIEST BAND...WITH LIGHTER AMOUNTS ON
EITHER SIDE...BUT NOT EXACTLY SURE WHERE THE HEAVIEST BAND WILL BE
LOCATED. STILL A FEW QUESTIONS WITH THIS EVENT...AND THE SMART
THING TO DO AT THIS POINT WILL BE A WINTER STORM WATCH ACROSS THE
AREA WHERE THE HEAVY SNOW IS POSSIBLE.

TUESDAY-WEDNESDAY NIGHT...MID-UPPER LEVEL TROUGH WILL PASS THROUGH
THE REGION TUESDAY NIGHT WITH A COLD FRONT PASSING THROUGH. WILL
NEED TO WATCH WINDS TUE NIGHT AS THE COLD FRONT MOVES THROUGH.
THERE SHOULD ALSO BE AN AREA OF SNOW SHOWERS. ABOVE NORMAL TEMPS
WILL TRANSITION TO BELOW NORMAL BY WEDNESDAY.

LONG TERM (THURSDAY-SUNDAY)...
MODELS IN GOOD AGREEMENT THROUGH THE EXTENDED WITH A COLD START
THEN MODERATING TEMPS WITH GENERALLY DRY CONDITIONS THROUGH THE
END OF THE WEEK. ARCTIC SFC HIGH PRESSURE THURSDAY ACROSS THE
WESTERN DAKOTAS TO BRING ANOTHER ROUND OF BLO ZERO HIGH TEMPS AND
NW WINDS TO COMBINE FOR DANGEROUSLY COLD WIND CHILLS THURSDAY AND
FRIDAY. MODERATING TEMPS BEGIN FRIDAY WITH 500MB FLOW BECOMING
LESS NORTHERLY AND A BIT MORE NWLY AS THICKNESSES RISE WITH THE
DEPARTURE OF ARCTIC SFC HIGH. CLIPPER SYSTEM WILL BRING A SCHC OF
-SN ON FRI/SAT WITH A RETURN TO THE UPPER TEENS AND LOW 20S FOR
NEXT SUNDAY.

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FREEZING RAIN ADVISORY UNTIL NOON CST TODAY FOR NDZ027>030-038-
039-049-052-053.

WINTER STORM WATCH FROM 3 PM CST THIS AFTERNOON THROUGH LATE
TONIGHT FOR NDZ052-053.

MN...FREEZING RAIN ADVISORY UNTIL NOON CST TODAY FOR MNZ001>003-
013>016-022>024-027>032-040.

WINTER STORM WATCH FROM 3 PM CST THIS AFTERNOON THROUGH LATE
TONIGHT FOR MNZ003-016-017-022>024-027>032-040.

$$
TG/JK

AREA FORECAST DISCUSSION...UPDATED

NWS GRAND FORKS ND

428 AM CST MON JAN 28 2013

.UPDATE...DID NOT WANT TO COMPLICATE THINGS ANY MORE...BUT GETTING
REPORTS OF FREEZING DRIZZLE ACROSS THE SOUTHERN HALF OF THE
FORECAST AREA RESULTING IN ICY ROADS. WILL NEED TO ISSUE A
FREEZING RAIN ADVISORY (FOR FREEZING DRIZZLE) THROUGH THE MORNING
HOURS. SNOW SHOWERS WILL MOVE ACROSS THE NORTHERN PART OF THIS
ADVISORY OVER THE NEXT FEW HOURS...WHICH WILL LIKELY END THE
FREEZING DRIZZLE HERE. LATEST RAP INDICATES VISIBILITY WILL
IMPROVE ACROSS THE SOUTHERN PART OF THIS ADVISORY BY NOON...WHICH
SHOULD CORRESPOND TO THE END OF THE FREEZING DRIZZLE.

.AVIATION...EXPECT MVFR/IFR CONDITIONS TO AFFECT AREAS ALONG AND
EAST OF THE RED RIVER VALLEY THROUGH THE MORNING HOURS. THE
NORTHERN/WESTERN EDGE OF THESE LOW CIGS WILL LIKELY ADVECT
EASTWARD THIS AFTERNOON...WITH VFR CONDITIONS POSSIBLY MOVING INTO
KGFK/KTVF BY LATE AFTERNOON. FREEZING DRIZZLE POSSIBLE THROUGH THE
MORNING HOURS...THE A BAND OF HEAVIER SNOW WILL MOVE INTO WEST
CENTRAL MINNESOTA LATER THIS AFTERNOON. WINDS WILL REMAIN LIGHT
THROUGH THE PERIOD.

.PREV DISCUSSION... /ISSUED 335 AM CST MON JAN 28 2013/

SHORT TERM (TODAY-WED NIGHT)...THE MAIN CONCERN THIS PERIOD WILL
BE THE POTENTIAL OF A HEAVY SNOW BAND ACROSS THE SOUTHEAST FA. 00Z
MODELS IN DECENT AGREEMENT AND WILL USE A BLEND.

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FREEZING RAIN ADVISORY UNTIL NOON CST TODAY FOR NDZ027>030-038-
039-049-052-053.

WINTER STORM WATCH FROM 3 PM CST THIS AFTERNOON THROUGH LATE
TONIGHT FOR NDZ052-053.

MN...FREEZING RAIN ADVISORY UNTIL NOON CST TODAY FOR MNZ001>003-
022>024-027>032-040.

WINTER STORM WATCH FROM 3 PM CST THIS AFTERNOON THROUGH LATE
TONIGHT FOR MNZ003-016-017-022>024-027>032-040.

$$
TG/JK

AREA FORECAST DISCUSSION

NWS BISMARCK ND

1001 PM CST SUN JAN 27 2013

.DISCUSSION...

NO MAJOR CHANGES PLANNED WITH THIS FORECAST UPDATE. THIS BIGGEST
CHALLENGE IS IF A DENSE FOG ADVISORY WILL BECOME NECESSARY ACROSS
THE JAMES RIVER VALLEY UNDERNEATH AN EXPANDING STRATUS DECK. FOR
NOW...WILL HOLD OFF ON AN ADVISORY. THAT SAID...THE LATEST RUNS
OF THE HRRR SUGGEST VISIBILITIES POTENTIALLY FALLING TO A QUARTER
MILE OR LESS...WITH KABR AND KHON ALREADY AT THESE LEVELS. WILL
CONTINUE TO MONITOR TRENDS SHOULD A ADVISORY BECOME NECESSARY.

.AVIATION...

AS OF 04 UTC...A WEAK FRONTAL BOUNDARY WAS LOCATED BETWEEN THE
KDIK/KISN AND THE KMOT/KBIS TERMINALS. A BAND OF PRECIPITATION WAS
DEVELOPING BEHIND THIS BOUNDARY. PRECIPITATION MAY START AS A MIX
OF SNOW...SLEET AND FREEZING RAIN...QUICKLY CHANGING OVER TO ALL
SNOW. IFR CIGS/VISIBILITIES IN STRATUS...FOG AND SNOW CURRENTLY
IMPACTING KISN AND KDIK ARE FORECAST TO SOON IMPACT KMOT AND KBIS
BY 06-08 UTC. FOR KJMS...MVFR/IFR CEILINGS WITH PATCHY FOG IS
EXPECTED WITH INCREASING LOW LEVEL MOISTURE.

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM/AVIATION...AYD

AREA FORECAST DISCUSSION

NWS WILMINGTON OH

952 PM EST TUE JAN 29 2013

.SYNOPSIS...
WARM TEMPERATURES WILL BE IN PLACE AHEAD OF A COLD FRONT THAT WILL
ARRIVE WEDNESDAY. STRONG STORMS ORGANIZED AHEAD OF THE FRONT WILL
AFFECT OUR AREA DURING THE EARLY TO MID MORNING HOURS WEDNESDAY.
BEHIND THIS SYSTEM...COLDER AIR WILL RETURN TO THE REGION FOR THE
REMAINDER OF THE WEEK.

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
MODELS KEEP OFFERING SUBTLE TIMING ISSUES FOR THE ARRIVAL OF A
PREFRONTAL TROUGH LATE TONIGHT INTO WEDNESDAY MORNING THAT WILL
MOSTLY LIKELY BE REALIZED AS A WELL DEFINED BAND OF SHOWERS AND
EMBEDDED THUNDERSTORMS. DID NOT WANT TO MESS WITH THE TIMING TOO
MUCH UNTIL WE CAN GET A MORE DEFINED TRACK TO OUR WEST AND WITH A
CHANCE TO LOOK AT THE FULL SUITE OF MODELS BOTH HIGH
RES/CONVECTIVE ALLOWING AND LOWER RES/CONVECTIVE PARAMETERIZATION.

IT APPEARS THAT THE LATEST 00Z NAM-WRF TRICKLING IN IS NOT
DEPICTING ANY MUCAPE WITH CURRENT CONVECTION TO OUR WEST/NORTHWEST
WHILE THE LATEST RAP AT LEAST SHOWS 200-400 J/KG. BY THE TIME THE
LINE ARRIVES LATE TONIGHT INTO WEDNESDAY...BEST ESTIMATE OF MUCAPE
SHOULD STILL BE IN THE 200-400 J/KG. EVEN IF THIS DOES NOT RESULT
IN MUCH LIGHTNING ACTIVITY...A VERY STRONG 925 MB TO 850 MB LOW
LEVEL JET WILL ACCOMPANY IT...AND IT CAN NOT BE TAKEN LIGHTLY. IT
WOULD NOT TAKE MUCH FOR CONVECTIVE DOWNDRAFTS TO BRING DOWN 50
KNOT WINDS TO THE SURFACE WHEN THEY ARE FORECAST TO BE IN THE
LOWER 50S KNOTS AROUND 1500 FEET. SO...CURRENT HWO HIGHLIGHTS
THIS. ANOTHER CONCERN WILL BE THE THREAT FOR HIGHER WIND GUSTS
BEFORE THE LINE OF ARRIVES SHOULD SOME STRAY SHOWER ACTIVITY
PRECEDE IT WHICH MAY BRING DOWN STRONGER WINDS DUE TO LIGHT
SPRINKLES OR VIRGA. WILL CONTINUE TO MONITOR THIS. TEMPERATURES
OVERNIGHT WILL REMAIN VERY WARM DUE TO INCREASING SOUTHERLY FLOW
AHEAD OF THE PREFRONTAL TROUGH AND SHOULD BOTTOM OUT IN THE UPPER
50S TO THE LOWER 60S BY SUNRISE.

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
BEHIND THE LEADING EDGE OF THIS CONVECTIVE COMPLEX WILL BE AN AREA
OF MORE STRATIFORM PRECIPITATION AND LIGHTER WINDS THAT WILL LAST
INTO THE MID MORNING HOURS IN THE WEST...AND THE EARLY AFTERNOON
IN THE EAST. ALL THIS ACTIVITY WILL BE PRE-FRONTAL...THEREFORE A
MARKED TEMPERATURE DECREASE WILL NOT BE EXPECTED UNTIL LATER IN
THE AFTERNOON AS THE FRONT PASSES. SOME SHOWER ACTIVITY IS
EXPECTED AS THE FRONT PASSES WITH A WIND SHIFT OUT THE NORTHWEST.
WINDS WILL BECOME GUSTY FROM THE AFTERNOON INTO THE LATE EVENING
BEHIND THE FRONT. WITH THE LOW RAPIDLY DEPARTING...DO NOT EXPECT
WINDS TO GUST MUCH OVER 40 MPH BEHIND THE FRONT. CAA SNOW SHOWERS
WILL BE POSSIBLE DURING THE EVENING BEHIND THE FRONT...BEFORE THE
ORIENTATION OF THE FLOW BECOMES MORE WESTERLY...ENDING ANY SNOW
SHOWERS LATE WEDNESDAY NIGHT.

BREEZY CONDITIONS WILL CONTINUE THURSDAY AS HIGH PRESSURE TRIES TO
BUILD SOUTHEASTWARD ACROSS THE PLAINS. A WEAK DISTURBANCE RIDING
UNDERNEATH THE BASE OF A DEEP TROUGH CENTERED OVER EASTERN CANADA
WILL PASS ACROSS OUR AREA THURSDAY NIGHT. MODELS VARY A BIT IN
THEIR STRENGTH OF THIS FEATURE AND IN THE MOISTURE AVAILABLE FOR IT
TO WORK WITH. CURRENT INDICATIONS ARE THAT SOME OF OUR FORECAST
AREA...PARTICULARLY THE SOUTH...MAY SEE SOME SNOW OVERNIGHT
THURSDAY NIGHT.

.LONG TERM /FRIDAY THROUGH TUESDAY/...
A SHORTWAVE WILL BE DEPARTING THE GREAT LAKES REGION ON
FRIDAY...WITH CLOUDS REMAINING OVER THE UPPER OHIO VALLEY TO START
THE PERIOD. IT APPEARS THAT THE SNOW WILL BE LIMITED TO AREAS
NORTHEAST OF THE ILN CWA BY FRIDAY...SO NO POPS HAVE BEEN INCLUDED
IN THE FORECAST.

THE AIR MASS ON FRIDAY WILL BE VERY COLD...WITH 850MB TEMPERATURES
OVER THE CWA RANGING FROM -16 TO -20 DEGREES CELSIUS. STANDARDIZED
ANOMALIES INDICATE THESE TEMPERATURES APPROACH 2 STANDARD DEVIATIONS
BELOW NORMAL...NOT AS SIGNIFICANT AS THE ARCTIC AIR LAST WEEK...BUT
STILL RATHER COLD. MAX TEMPS ON FRIDAY HAVE BEEN LOWERED
SLIGHTLY...THOUGH NOT AS COLD AS THE RAW GFS.

THROUGH THE REST OF THE PERIOD...OVERALL MODEL AGREEMENT IN THE
LARGE-SCALE PATTERN IS GOOD THROUGH MONDAY. ON MONDAY AND
LATER...GFSE SPREADS BECOME FAIRLY LARGE...WITH LESS CERTAINTY IN
THE STRENGTH AND TIMING OF THE NEXT WEATHER SYSTEMS TO IMPACT THE
REGION.

ON SATURDAY...A WEAK NORTHWEST FLOW SYSTEM WILL MOVE THROUGH THE
REGION. WITH SOME INCREASING CONFIDENCE IN THE TIMING OF THIS
SYSTEM...POPS WERE INCREASED WELL INTO THE CHANCE CATEGORY FOR THE
WHOLE CWA. VERIFYING AS CURRENTLY DEPICTED IN THE MODELS...THIS
SYSTEM COULD PRODUCE AN INCH OR TWO OF SNOW.

TEMPERATURES WILL GRADUALLY MODERATE OVER THE NEXT FEW DAYS...AS
SURFACE HIGH PRESSURE BUILDS IN BEHIND THE SATURDAY SYSTEM. THE
TEMPERATURE FORECAST HAS BEEN INCREASED SLIGHTLY THROUGH MONDAY.

A COLD FRONT IS FORECAST TO MOVE THROUGH THE CWA ON MONDAY NIGHT.
WHILE THE GFS/ECMWF ARE IN DECENT AGREEMENT ON TIMING...THE STRENGTH
OF THE FRONT AND AMOUNT OF MOISTURE AVAILABLE REMAIN UNCERTAIN.
TEMPERATURES WITH THIS FRONT WILL LIKELY SUPPORT A MIX OF RAIN OR
SNOW...WITH NOTHING INDICATING ICY PRECIPITATION AT THIS TIME.

.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
A VERY DYNAMIC WEATHER SYSTEM WILL AFFECT THE GREAT LAKES AND OHIO
VALLEY REGION THROUGH THE TAF PERIOD. LOW PRESSURE OVER MISSOURI
WILL DEEPEN AS IT MOVES NORTHEAST TO WESTERN LOWER MICHIGAN BY 12Z
WEDNESDAY...THEN IT WILL CONTINUE TO A POSITION NEAR SOUTHERN
ONTARIO BY 00Z THURSDAY. THERE WILL BE SEVERAL AVIATION ISSUES
WITH THIS SYSTEM. THE FIRST WILL BE A PREFRONTAL TROUGH THAT IS
FORECAST TO MOVE IN ADVANCE OF THE COLD FRONT ACROSS THE REGION
BETWEEN 09Z AND 15Z. THIS FEATURE WILL LIKELY EXHIBIT A WELL
DEFINED BAND OF SHOWERS AND POSSIBLY SOME EMBEDDED THUNDERSTORMS.
THE FEATURE WILL BE MOVING WITHIN A VERY STRONG WIND REGIME WITH
WINDS FORECAST TO BE IN THE LOWER 50 KNOTS NEAR 1500 FEET AND OVER
80 KNOTS NEAR 4000 FEET. AS SUCH...THE THREAT EXISTS FOR SOME WIND
GUSTS TO SURPASS 50 KNOTS AT THE SURFACE WHERE CONVECTIVE
DOWNDRAFTS OCCUR. AT THIS TIME...HAVE INTRODUCED WIDESPREAD
SHOWERS WITH MVFR/IFR CEILINGS/VSBYS WITH THE VCTS/CB DESCRIPTORS AS
IT IS STILL TOO EARLY TO PINPOINT WHICH TAFS MAY ACTUALLY
EXPERIENCE THUNDER. ALSO...HAVE CONTINUED WITH THE 40 KNOT WIND
GUSTS WITH THIS LINE OF CONVECTION...ALLOWING SHORT TERM
OBSERVATIONS DICTATE WHETHER THESE VALUES NEED TO BE ADJUSTED
UPWARD AS THE FEATURE MOVES THROUGH THE REGION. ONCE THIS
PREFRONTAL TROUGH PASSES BY...WE SHOULD GET INTO A PERIOD OF
SHOWERS WITH MVFR CONDITIONS. THEREAFTER...MODELS SUGGEST A LULL IN
THE ACTIVITY UNTIL A STRONG COLD FRONT PUSHES EAST ACROSS THE AREA
FROM LATE WEDNESDAY AFTERNOON INTO THE EVENING. THIS WILL USHER IN
COLDER AIR WITH THE THREAT OF A FEW SNOW SHOWERS FOLLOWING ITS
PASSAGE. AVIATORS CAN ALSO EXPECT BREEZY TO WINDY CONDITIONS
OUTSIDE OF CONVECTION WITH THE WORST PROLONGED AND HIGHEST WIND
GUSTS OCCURRING IN THE COLD AIR ADVECTION BEHIND THE COLD FRONT
WHERE WINDS COULD GUST AS HIGH AS 35 KNOTS.

OUTLOOK...BREEZY TO WINDY CONDITIONS TO CONTINUE WEDNESDAY NIGHT
INTO THURSDAY. MVFR CEILINGS TO CONTINUE THURSDAY INTO THURSDAY
NIGHT WITH MVFR VSBYS POSSIBLE THURSDAY NIGHT. MVFR CONDITIONS
POSSIBLE AGAIN SATURDAY INTO SUNDAY.

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

$$
SYNOPSIS...HICKMAN/LATTO
NEAR TERM...HICKMAN/LATTO
SHORT TERM...LATTO
LONG TERM...HATZOS
AVIATION...HICKMAN

AREA FORECAST DISCUSSION

NWS NASHVILLE TN

839 PM CST TUE JAN 29 2013

.UPDATE...
VWP CONTINUING TO SHOW A GRADUAL INCREASE IN
WIND SPEEDS...PARTICULARLY SEVERAL THOUSAND FEET ABOVE GROUND.
MODELS STILL INDICATING SOME LOWER LEVEL SUBSIDENCE OUT AHEAD OF
THE CONVECTION TO OUR WEST. LATEST TN STATE ROUNDUP SHOWING SOME
30 TO 35 MPH GUSTS ACROSS WESTERN TN. THESE HIGHER SPEEDS WILL
CONTINUE TO MOVE OUR WAY OVERNIGHT.

CONVECTION WISE...TWO MAIN AREAS OF PRE FRONTAL FORCING INDICATED
ACROSS CENTRAL AND EASTERN AR NOW. ITS LOOKING AS THOUGH THE
LEADING LINE WILL REACH THE MS RIVER AROUND 04Z OR 05Z. THERE IS A
LEADING AREA OF CONVECTION ACROSS NRN MS BUT IT APPEARS TO BE
OUTRUNNING THE BETTER INSTABILITY AT THIS TIME.

LATEST HRRR DATA SHOWS THE MAIN LINE OF STORMS REACHING THE TN
RIVER AROUND 08Z. LATEST NAM DATA STILL SHOWING A GOOD DEAL OF
INSTABILITY WITH NEG SHOWALTER VALUES TRAVERSING THE AREA.
FURTHERMORE...HELICITY VALUES REMAIN QUITE HIGH. THUS...THE
TORNADO WATCHES TO OUR WEST ARE LIKELY TO PROPAGATE EASTWARD
OVERNIGHT. NAM CONTINUES TO RUN A FEW HOURS TOO SLOW WITH THE
EXPECTED CONVECTION. NEAR 60 DEW POINTS NOW COVER THE BULK OF OUR
AREA...WITH SOME LOWER TO MID 60S DEWPOINTS ACROSS SOUTHERN MIDDLE
TN.

NO ADDITIONAL UPDATES TO THE ZONES ARE NEEDED FOR NOW. THERE COULD
STILL BE SOME PRE MIDNIGHT CONVECTION...BUT THE BULK OF THE
ACTIVITY WILL BE AFTER MIDNIGHT. UPDATES TO COMMENCE WITH THE
LIKELY INTRODUCTION OF CONVECTIVE WATCH BOXES LATER TONIGHT.

.PREV DISCUSSION... /ISSUED 614 PM CST TUE JAN 29 2013/

UPDATE...00Z AVIATION DISCUSSION.

AVIATION...00Z AVIATION DISCUSSION.
SFC PRESSURE GRADIENT WILL CONTINUE TO INCREASE AS APPROACHING COLD FRONTS
MOVE INTO/ACROSS MID STATE DURING 30/12Z-30/24Z. ALSO...STRONG LOW LEVEL
WIND SHEAR JUST OFF SFC WITH SLY WINDS 60KT-70KT EXPECTED THRU AROUND 30/12Z...
WITH SOME SFC GUSTS TO AROUND 45KT EVEN POSSIBLE ALONG LEADING EDGE. A LINE
OF STORMS...AT LEAST IN VCNTY OF COLD FRONTAL PASSAGE...AND MAY ALSO FORM
OUT AHEAD...AS MOISTURE...INSTABILITY...AND LIFTING MECHANISMS COME INTO
PLAY...AND THEN QUICKLY MOVE NEWD. EXPECT IMPACTS AT CKV AROUND 30/07Z...
BNA 30/08Z...AND CSV 30/11Z. SOME HEAVY RAINFALL WILL ALSO ACCOMPANY THE
STRONGER STORMS WITH SVR TSTMS POSSIBLY ALSO OUT AHEAD AND EMBEDDED IN
LINE. TIMING AND DURATION OF THE LINE OF STORMS IS STILL UNCERTAIN...HOWEVER
CKV/BNA CAN EXPECT THE STRONGEST STORMS TO MOVE OUT OF THE AREA BETWEEN
30/11-30/12Z. CSV MAY CONTINUE TO EXPERIENCE STRONGEST STORMS UNTIL AROUND
30/15Z. WINDS ARE STILL EXPECTED TO REMAIN AROUND 20 KTS WITH GUSTS TO 30 KTS
FOR AREA THRU 30/24Z. CHANGE OVER TO ALL SHWRS IS EXPECTED W TO E DURING THE
30/18Z-30/24Z TOO.

PREV DISCUSSION.../ISSUED 536 PM CST TUE JAN 29 2013/

UPDATE...
MAIN FRONTAL BOUNDARY EXTENDS FROM CENTRAL MO SW THROUGH EASTERN
OK. SEVERAL PRE FRONTAL BOUNDARIES IN ADVANCE OF THIS FEATURE WITH
THE MAIN LINE OF CONVECTION CURRENTLY OVER NW AR. INSTABILITY AXIS
WILL CONTINUE TO TRANSFER EASTWARD OVERNIGHT WITH THE MAIN LINE OF
STORMS REACHING FAR WESTERN TN BETWEEN 03Z AND 07Z. IN ADVANCE OF
THIS HOWEVER...CONVECTION STILL POSSIBLE AND WE ARE ALREADY SEEING
SOME SHOWER AND TSTM ACTIVITY INTO PORTIONS OF EASTERN AR.

GFS LOOKING A LITTLE FAST WITH THE MAIN LINE WHILE THE NAM MAY BE
A LITTLE SLOW. BUT...THE MODELS ARE IN AGREEMENT WITH A VERY
STRONG LINEAR OMEGA FIELD MATCHING UP WITH A POWERFUL 70-80 KT
850 MB JET. FURTHERMORE...SHOWALTERS AT OR JUST BELOW ZERO WILL
ALIGN WITH AN IMPRESSIVE LOW TO MID LEVEL THETA-E AXIS TO HELP
PROPEL THE CONVECTION.

IN ADDITION TO THE SEVERE WEATHER THREAT...THE PRESSURE GRADIENT
IS EXPECTED TO TIGHTEN UP BETWEEN NOW AND THROUGH 06Z. GOOD LOWER
LEVEL SUBSIDENCE IS INDICATED AS THE WINDS ALOFT BEGIN TO
STRENGTHEN. THUS...GUSTS TO 35 OR 40 MPH SHOULD BE EASY TO REACH
OVERNIGHT.

FOR THE UPDATE...WILL ATTEMPT TO ADJUST GRIDS SO AS TO INCREASE
THE WIND SPEEDS IN THE ZONE TEXT. REMAINDER OF FCST IS IN GOOD
SHAPE. THREAT OF STORMS DOES EXIST AHEAD OF THE MAIN LINE SO WILL
LEAVE THE DAMAGE POTENTIAL IN PRIOR TO MIDNIGHT FOR NOW. UPDATE
OUT SHORTLY.

PREV DISCUSSION... /ISSUED 349 PM CST TUE JAN 29 2013/

DISCUSSION...

THE FRONTAL PASSAGE AND ASSOCIATED SQUALL LINE WILL BE THE FOCUS OF
THE FORECAST.

LOW LEVEL WINDS ARE EXPECTED TO CONTINUE TO INCREASE
AHEAD OF THE APPROACHING SYSTEM. A WIND ADVISORY CONTINUES FOR AREAS
WEST OF THE PLATEAU UNTIL 6 PM WEDNESDAY...WHILE AREAS ALONG THE
PLATEAU ARE UNDER A WIND ADVISORY STARTING AT 6 PM TONIGHT AND
LASTING THROUGH 9 PM WEDNESDAY. SUSTAINED 25 MPH WINDS ARE
POSSIBLE WITH GUSTS TO 45 MPH.

PLENTY OF MOISTURE AND WARM AIR WILL CONTINUE TO SURGE INTO
MIDDLE TN AHEAD OF THE SYSTEM. A FEW ISOLATED SHOWERS MAY BE
POSSIBLE AHEAD OF THE LINE...BEFORE MIDNIGHT. HOWEVER THE MAIN
THREAT REMAINS WITHIN AND AROUND THE EXPECTED SQUALL LINE...WITH
THE MAIN CONCERNS BEING DAMAGING STRAIGHT LINE WINDS AND QLCS
TORNADOES. THE ETA OF THE MAIN ACTIVITY WILL BE 11 PM TO 2 AM FOR
AREAS NEAR THE TENNESSEE RIVER....1 AM TO 4 AM FOR AREAS ALONG THE
I-65 CORRIDOR AND 4 AM TO 9 AM FOR AREAS ALONG AND NEAR THE
CUMBERLAND PLATEAU. PWAT VALUES STILL REMAIN RELATIVELY HIGH FOR
THIS TIME OF YEAR, HOWEVER DUE TO THE RATHER QUICK MOVEMENT OF THE
STORM SYSTEM FLOODING DOES NOT APPEAR TO BE A MAJOR ISSUE. 1 TO
1.5 INCHES OF RAINFALL WILL BE POSSIBLE ACROSS THE AREA WITH
LOCALLY HIGHER AMOUNTS WITHIN THE STRONGEST CELLS. BECAUSE THE
GROUND WILL BE FAIRLY SATURATED EVEN SUB-SEVERE WIND GUSTS COULD
CAUSE TREES TO TOPPLE OVER.
THE MAIN LINE OF STORMS IS EXPECTED TO EXIT THE PLATEAU BY MID
MORNING ON WEDNESDAY. SOME SHOWERS MAY LINGER AROUND THE MID STATE
INTO THE AFTERNOON...AFTER THE DEPARTURE OF THE MAIN LINE OF
STORMS...BUT BY LATE AFTERNOON THE WINDS WILL BEGIN TO SHIFT FROM
SOUTHERLY TO WESTERLY...USHERING COLDER DRIER AIR INTO THE AREA FROM
THE WEST.

BY WEDNESDAY NIGHT PRECIPITATION WILL TAPER OFF WEST TO EAST...WITH
A RAIN SNOW MIX TRANSITIONING TO LIGHT SNOW SHOWERS OR FLURRIES OVER
THE PLATEAU AND HIGHER TERRAIN LATE. COLD AIR ADVECTION PEAKS WITH
850MB TEMPS DROPPING TO ABOUT -8C ON WEDNESDAY AS BROAD UPPER TROUGH
OVER THE CONUS PERSISTS. EXPECT MARGINAL WARMING ON THURSDAY BEFORE
A WEAK BUT QUICK MOVING SHORTWAVE ROTATES AROUND THE TROUGH THURSDAY
NIGHT BRINGING THE POSSIBILITY OF LIGHT SNOWFALL TO THE AREA. LACK OF
MOISTURE SHOULD KEEP ACCUMULATIONS DOWN...RANGING FROM A DUSTING TO
A HALF INCH OVER THE LOWER ELEVATIONS...TO AROUND AN INCH OVER
PORTIONS OF THE PLATEAU. THIS SYSTEM COULD STRENGTHEN OR WEAKEN WITH
SUBSEQUENT MODEL RUNS...SO EXPECT CHANGES AS THE FORECAST TIME DRAWS
NEAR. FOR FRIDAY...NORTHWESTERLY WINDS OF 5-10KTS ALONG WITH COLD
AIR ADVECTION DROPPING 925MB TEMPS TO -8C TO -12C SHOULD MAKE FOR AN
UNPLEASANT DAY. BUNDLE UP.

BY THE WEEKEND...THE UPPER TROUGH LIFTS SLIGHTLY ALLOWING FOR A BIT
OF WARMING...BUT ANOTHER WEAK SHORTWAVE ROTATES AROUND AND BRINGS
PRECIPITATION BACK TO THE MID-STATE. THE WARMING SHOULD BE ENOUGH TO
CHANGE EXPECTED PRECIP TO LIGHT RAIN SHOWERS...THOUGH A RAIN-SNOW
MIX IS EXPECTED OVER THE HIGHER TERRAIN. LONG-RANGE MODELS INDICATE
AN UPPER TROUGH WILL DEVELOP OVER THE CENTRAL STATES ALLOWING FOR A
SOUTHERLY FLOW TO BRING WARM AND MOIST AIR BACK TO THE MID-STATE. AT
THIS POINT ITS UNCERTAIN HOW MUCH WILL OCCUR...SO WILL LIMIT WEATHER
TO CHANCE OF RAIN SHOWERS...AND WILL MONITOR MODEL UPDATES FOR
THUNDERSTORM POTENTIAL.

.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 9 PM CST WEDNESDAY FOR TNZ011-032>034-065-
066-078>080.

WIND ADVISORY UNTIL 6 PM CST WEDNESDAY FOR TNZ005>010-022>031-
056>064-075-077-093>095.

AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

838 PM CST TUE JAN 29 2013

.UPDATE...
EVENING FORECAST UPDATE.

.DISCUSSION...
GUST FRONT...LINE OF STORMS...PACIFIC FRONT ARE ALL MOVING INTO
SE TX BASICALLY FROM NACOGDOCHES TO HUNTSVILLE TO BELLVILLE THIS
EVENING. GUST FRONT MAY BRING SOME GUSTY WINDS OF 30-40KTS BUT
WINDS SHOULD BE FAIRLY BRIEF. STRONGEST STORM CONTINUES TO PUSH
THROUGH WALKER CO RATHER QUICKLY. MAIN THREAT WILL BE DAMAGING
WINDS BUT THINK WINDS WILL REMAIN BELOW SEVERE LEVELS. INSTABILITY
SEEMS RATHER LIMITED AND CAPPING IS JUST ENOUGH TO INHIBIT DEEP
CONVECTION. UPDATED POPS FOR ONGOING TRENDS. MAY NEED TO UPDATE
LATER THIS EVENING AS LINE OF STORMS PUSHES TOWARDS HOUSTON.
REALLY JUST EXPECTING A THIN LINE OF SHOWERS AND A FEW STORMS.
REST OF THE FORECAST LOOKS ON TRACK.

.PREV DISCUSSION... /ISSUED 539 PM CST TUE JAN 29 2013/

DISCUSSION...
SEE 00Z AVIATION DISCUSSION.

AVIATION...
NOT MANY CHANGES TO PREVIOUS TAF PACKAGE. FCST SOUNDINGS SHOW A
STOUT CAP IN PLACE...ESPECIALLY SOUTHERN TAF SITES. LATEST RAP 13
SHOWS THE CAP ERODING QUICKLY AND SCT SHRA/TSRA BETWEEN 03-06Z
OVER THE HOUSTON TERMINALS. THE RAP SEEMS TO AGGRESSIVE WITH
BREAKING THE CAP SO LEANED TOWARD THE MORE STABLE AND CAPPED
NAM/GFS. MVFR CIGS POSSIBLE THIS EVENING WITH VFR CONDS EXPECTED
TO DEVELOP BETWEEN 06-09Z. BUMPED WINDS UP A BIT FOR WEDNESDAY AND
CONTINUED TREND WITH WRAP AROUND CLOUD COVER WITH SCT-BKN CONDS
POSSIBLE OVER NORTHERN TAF SITES. 43

PREV DISCUSSION... /ISSUED 329 PM CST TUE JAN 29 2013/

DISCUSSION...
IT`S BEEN ON THE BREEZY SIDE ACROSS MUCH OF SOUTHEAST TEXAS TODAY...AND
CLOUD COVER HAS MANAGED TO KEEP HIGH TEMPERATURES ALMOST AREA WIDE UNDER
80 DEGREES. A LINE OF SHOWERS AND THUNDERSTORMS (SOME SEVERE) ACROSS
A NORTH CENTRAL TEXAS COLD FRONT WILL BE MOVING INTO SOUTHEAST TEXAS
THIS EVENING. THERE CONTINUES TO BE A RISK OF STRONG/SEVERE STORMS ACROSS
THE NORTHERN HALF OF OUR AREA WHERE THE CAP IS EXPECTED TO WEAKEN. FURTHER
SOUTH (SAY AROUND AND SOUTH OF I-10)...THE CAP SHOULD HOLD RESULTING
IN A LOWER RISK OF SEVERE DEVELOPMENT. THESE STORMS ARE EXPECTED TO
BE OFF THE COAST AROUND OR SHORTLY AFTER MIDNIGHT WITH COOLER AIR FILTERING
INTO THE AREA BEHIND THE BOUNDARY. EXPECTING IT TO BE BREEZY AND COOLER
ON WEDNESDAY...AND A WIND ADVISORY MIGHT BE NEEDED NEAR THE COAST/COASTAL
COUNTIES. ALSO...ELEVATED FIRE WEATHER CONDITIONS ARE STILL ANTICIPATED
DURING THE DAY DUE TO THE GUSTY WINDS AND VERY LOW HUMIDITIES. SURFACE
HIGH PRESSURE SETTLING INTO THE AREA WEDNESDAY NIGHT AND EDGING OFF
TO OUR EAST ON THURSDAY WILL BRING QUIET WEATHER TO OUR AREA. A GRADUAL
WARM UP IS EXPECTED FOR THE END OF THE WEEK AND ON INTO THE WEEKEND
UNDER MAINLY LIGHT SOUTH WINDS. THE NEXT COLD FRONT IS CURRENTLY EXPECTED
TO MOVE THROUGH THE AREA EARLY NEXT WEEK. 42

MARINE...
STRONG ONSHORE FLOW WILL PERSIST THROUGH THIS EVENING AHEAD OF AN
APPROACHING COLD FRONT. THE FRONT WILL MOVE OFFSHORE AROUND MIDNIGHT
AND PUSH THROUGH THE COASTAL WATERS OVERNIGHT BRINING WINDS OF 15 TO
25 KNOTS WITH HIGHER GUSTS. THUNDERSTORMS MAY BE POSSIBLE AROUND
GALVESTON BAY AND THE EASTERN WATERS ALONG AND AHEAD OF THE FRONT.
HAVE EXTENDED SCEC FOR GALVESTON BAY THROUGH 6PM WEDNESDAY EVENING
BUT WINDS MAY INCREASE ENOUGH WEDNESDAY AFTERNOON TO SUPPORT A BRIEF
SCA FOR GALVESTON BAY. ELSEWHERE...SCA CONDITIONS EXPECTED THROUGH
WEDNESDAY AFTERNOON. 38

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 44 64 36 66 41 / 60 0 0 0 0
HOUSTON (IAH) 49 65 38 67 42 / 50 0 0 0 0
GALVESTON (GLS) 54 64 46 66 50 / 40 0 0 0 0

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 6 PM CST WEDNESDAY FOR THE FOLLOWING
ZONES: MATAGORDA BAY...WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT OUT 20 NM.

SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH WEDNESDAY AFTERNOON
FOR THE FOLLOWING ZONES: GALVESTON BAY.

SMALL CRAFT ADVISORY UNTIL MIDNIGHT CST WEDNESDAY NIGHT FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT 20 TO 60 NM.

DISCUSSION...39

AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

539 PM CST TUE JAN 29 2013

.DISCUSSION...
SEE 00Z AVIATION DISCUSSION.

.AVIATION...
NOT MANY CHANGES TO PREVIOUS TAF PACKAGE. FCST SOUNDINGS SHOW A
STOUT CAP IN PLACE...ESPECIALLY SOUTHERN TAF SITES. LATEST RAP 13
SHOWS THE CAP ERODING QUICKLY AND SCT SHRA/TSRA BETWEEN 03-06Z
OVER THE HOUSTON TERMINALS. THE RAP SEEMS TO AGGRESSIVE WITH
BREAKING THE CAP SO LEANED TOWARD THE MORE STABLE AND CAPPED
NAM/GFS. MVFR CIGS POSSIBLE THIS EVENING WITH VFR CONDS EXPECTED
TO DEVELOP BETWEEN 06-09Z. BUMPED WINDS UP A BIT FOR WEDNESDAY AND
CONTINUED TREND WITH WRAP AROUND CLOUD COVER WITH SCT-BKN CONDS
POSSIBLE OVER NORTHERN TAF SITES. 43

.PREV DISCUSSION... /ISSUED 329 PM CST TUE JAN 29 2013/

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 44 64 36 66 41 / 60 0 0 0 0
HOUSTON (IAH) 49 65 38 67 42 / 60 0 0 0 0
GALVESTON (GLS) 54 64 46 66 50 / 50 0 0 0 0

SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH WEDNESDAY AFTERNOON
FOR THE FOLLOWING ZONES: GALVESTON BAY.

SMALL CRAFT ADVISORY UNTIL MIDNIGHT CST WEDNESDAY NIGHT FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT 20 TO 60 NM.

DISCUSSION...39
AVIATION/MARINE...43

AREA FORECAST DISCUSSION

NWS BLACKSBURG VA

1010 PM EST TUE JAN 29 2013

.SYNOPSIS...
HIGH PRESSURE WILL BRING UNSEASONABLY WARM TEMPERATURES TO THE
AREA WEDNESDAY. A STRONG COLD FRONT WILL MOVE THROUGH THE REGION
LATE WEDNESDAY ACCOMPANIED BY SHOWERS WITH GUSTY WINDS AND HEAVY
RAIN. MUCH COLDER TEMPERATURES WILL RETURN FOR THE END OF THE WEEK
INTO THE WEEKEND AS HIGH PRESSURE MOVES SOUTHEAST FROM CANADA.

.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 955 PM EST TUESDAY...

STARTING TO SEE SOME LIGHT REFLECTIVITY IN THE SOUTHWEST
COUNTIES. EXPECT COVERAGE OF LIGHT RAIN TO EXPAND...ESPECIALLY
AFTER MIDNIGHT IN THE FAVORED EASTERN UPSLOPE AREAS. HAVE
INCREASED PROBABILITY OF PRECIPITATION ALONG THE SOUTHERN BLUE
RIDGE IN LINE WITH LATEST WRF AND RUC GUIDANCE.

BASED ON EXPECTED WINDS BY WEDNESDAY AFTERNOON...ESPECIALLY
LOOKING AT THE 850 MB WINDS APPROACHING 60-65 KNOTS AND SUSTAINED
WINDS ON THE DAN BUFKIT REACHING 20-25 MPH...HAVE EXPANDED THE
WIND ADVISORY FOR THE REST OF THE COUNTY WARNING AREA. ALSO
STRETCHED TIME OF HIGH WIND WARNING IN THE SOUTHWEST COUNTIES TO
START AT 09Z. EXPECTING IT WILL NOT TAKE AS LONG AS 6AM TO START
SEEING HIGH WINDS.

AS OF 300 PM EST TUESDAY...

ALL AREAS ARE EXPECTED TO BE CLOUDY BY EARLY WEDNESDAY MORNING.
LIGHT PRECIPITATION WILL DEVELOP BY MIDNIGHT...PRIMARILY ALONG THE
CREST OF THE BLUE RIDGE SOUTHWEST OF FLOYD VA INTO NW NC. AFTER
MIDNIGHT...THE FOCUS FOR THE BEST CHANCE OF RAIN WILL STILL BE
ALONG THE CREST OF THE BLUE RIDGE...HOWEVER...ALL PARTS OF THE
FORECAST AREA WILL HAVE AT LEAST A SLIGHT CHANCE.

OUR OTHER CONCERN FROM WIND INCLUDES GRADIENT PREVAILING WINDS IN
ADVANCE OF THE FRONT. DURING THE AFTERNOON AND EARLY EVENING
HOURS...WIND GUSTS AT THE HIGHER PEAKS ALONG AND WEST OF THE BLUE
RIDGE...MAY SEE WIND GUSTS IN EXCESS OF WIND ADVISORY
CRITERIA...40 KTS. WE ARE REFLECTING THIS CONCERN IN A WIND
ADVISORY THAT WILL BE IN EFFECT FROM NOON WEDNESDAY THROUGH
MIDNIGHT.

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
AS OF 345 PM EST TUESDAY...

FRONTAL PASSAGE WEDNESDAY EVENING WILL BRING DRAMATIC CHANGE IN
TEMPERATURE...READINGS FALLING FROM THE 50S/60S WEDNESDAY EVENING
INTO THE 20S/30S DURING THE OVERNIGHT. SLUG OF FRONTAL PRECIP WILL
MOVE RAPIDLY EAST ACROSS THE CWA DURING THE EVENING WITH DOWNPOUR
OF RAIN PRODUCING UPWARDS OF AN INCH OF RAIN IN LESS THAN 2 HOURS
TIME. THIS BURST OF HEAVY RAINFALL WITH THE FRONTAL PASSAGE WILL
LIKELY RESULT IN SUDDEN RISES TO AREA STREAMS. WILL FOREGO FLOOD
WATCH ATTM PER QUICK MOVEMENT OF SYSTEM AND LACK OF SUSTAINED
HEAVY RAIN THREAT. THAT SAID...STILL NOT A GOOD NIGHT TO BE
FLIRTING AROUND LOW WATER CROSSINGS.

FRONTAL PASSAGE HAS SLOWED A BIT COMPARED TO YESTERDAYS MODEL RUNS
BY ABOUT 3 HOURS. LOOKS LIKE FROPA WILL OCCUR AT BLF/TNB BETWEEN
6-8PM...7-9PM AT BCB/ROA...AND 8-10PM AT LYH/DAN. AFTER
FROPA...HEAVY RAIN THREAT WILL END...WINDS SHIFTING AROUND TO THE
WEST-NORTHWEST...TEMPERATURES PLUMMETING BACK TO MORE OF A WINTER
FLAVOR. ANY LINGERING MOISTURE IN THE MOUNTAINS WILL CHANGE TO
SNOW SHOWERS OR FLURRIES...WITH A HALF INCH TO AN INCH OF
ACCUMULATION POSSIBLE AT THE HIGHER ELEVATIONS LATE WEDNESDAY
NIGHT AND EARLY THURSDAY.

FOR THURSDAY AND INTO THE WEEKEND...COLD UPPER LEVEL TROUGH OF
LOW PRESSURE WILL SET UP SHOP OVER THE EASTERN CONUS...ANY PRECIP
PRODUCTION COMING FROM DISTURBANCES WITHIN THE NORTHERN STREAM.
NEXT OPPORTUNITY FOR PRECIP FROM ONE OF THESE DISTURBANCES WILL
COME THURSDAY NIGHT WITH A ROUND OF SNOW SHOWERS PASSING OVER THE
MOUNTAINS AROUND MIDNIGHT.

.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 305 PM EST TUESDAY...

HIGH PRESSURE BUILDS ACROSS THE REGION SUNDAY NIGHT INTO MONDAY
MORNING. ANOTHER LOW PRESSURE CENTER LIFTS NORTHEAST ACROSS GREAT
LAKES AND PUSHES A COLD FRONT TOWARDS OUR REGION MONDAY. THE COLD
FRONT ADVANCES ACROSS OUR REGION MONDAY NIGHT INTO TUESDAY. THE
GFS DEVELOPS A LOW PRESSURE CENTER OFF THE VIRGINIA COAST MONDAY
NIGHT AND LIFTS IT NORTHWARD ON TUESDAY. THE GFS SOLUTION
INDICATED THAT MORE SNOW...SEVERAL INCHES ARE POSSIBLE IN THE
WESTERN UPSLOPE AREAS ON MONDAY NIGHT INTO TUESDAY. WENT WITH
SCATTERED POPS FOR MONDAY NIGHT INTO TUESDAY AND WILL WATCH FOR
FURTHER RUNS TO SEE EVOLUTION AND DETAILS OF THIS STORM FOR EARLY
NEXT WEEK.

.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
AS OF 635 PM EST TUESDAY...

WINDS WILL HINDER AVIATION OPERATIONS LATE TONIGHT INTO WEDNESDAY.
QUICKLY DETERIORATING CONDITIONS WILL ALSO BE MAJOR CONCERN. TONIGHT
INTO EARLY WEDNESDAY...A COLD FRONT WILL APPROACH THE REGION FROM
THE WEST. 850 MB WINDS ARE EXPECTED TO INCREASE FROM THE 200 DEGREES
INTO THE 5O TO 60 KT RANGE BY LATE TONIGHT...AND 70 TO 80 KT RANGE
BY THE END OF THE DAY WEDNESDAY. MOISTURE WILL BE ON THE INCREASE
THROUGH THE NIGHT...WITH CIGS DEVELOPING IN THE MVFR RANGE. NEAR
SURFACE WINDS WILL MAINLY BE LIGHT EXCEPT AROUND KBLF WHERE SOME
GUSTINESS IS EXPECTED. OTHERWISE...AND EVEN AT KBLF...ANTICIPATE
STRONG LOW LEVEL SPEED SHEAR AROUND 1000 FT AGL STARTING AROUND
06Z...1AM..TONIGHT AND CONTINUING THROUGH ABOUT
14Z...9AM...WEDNESDAY WHEN LOW LEVEL MIXING HELPS TO ALLOW FOR SOME
STRONGER SURFACE GUSTS.

18Z NAM AND RAP CONTINUE TO SHOW RAIN SPREADING NORTHWARD ALONG
THE SOUTHERN BLUE RIDGE TONIGHT INTO WEDNESDAY. HIGH CONFIDENCE
THAT RAIN WILL FORM ACROSS THE AREA TOMORROW WITHIN THE PRE-
FRONTAL TROUGH. EXPECT AREAS OF RAIN ALONG AND EAST OF THE CREST
OF THE BLUE RIDGE BY 15Z...10AM.

STRONG COLD FRONT PUSHES THROUGH THE AREA WEDNESDAY EVENING WITH
HEAVY RAIN SHOWERS...QUICKLY CHANGING TO SNOW SHOWERS IN THE WEST.
SHARP WIND SHIFT WITH GUSTY CONDITIONS CONTINUING. UPSLOPE SNOW
SHOWERS CONTINUE BETWEEN KBLF AND KLWB THURSDAY...CLEARING EAST OF
THE BLUE RIDGE. NORTHWEST FLOW WILL PREVAIL FRIDAY THROUGH SUNDAY
WITH TWO POTENTIALS FOR CLIPPER SYSTEMS TO BRING UPSLOPE SNOW TO
SOUTHEAST WEST VIRGINIA AND FAVORED UPSLOPE AREAS...LATE THURSDAY
NIGHT IN FRIDAY AND SATURDAY NIGHT INTO SUNDAY. ANOTHER COLD FRONT
IS EXPECTED TO ARRIVE MONDAY INTO MONDAY NIGHT. WHILE TIMING
AND QPF OF INDIVIDUAL CLIPPER SYSTEMS REMAIN A CHALLENGE...THERE
IS A GOOD CHANCE THAT ACCUMULATING SNOWS ARE POSSIBLE FOR WESTERN
UPSLOPE AREAS IN THE MOUNTAINS THIS WEEKEND INTO EARLY NEXT WEEK.

.HYDROLOGY...
AN INCH /1.00/ TO AND INCH AND A HALF /1.50/ OF RAIN IS
ANTICIPATED WITH THE FRONTAL PASSAGE WEDNESDAY EVENING. THE BULK
OF THIS RAIN WILL BE ASSOCIATED WITH A SQUALL LINE OF SHOWERS
ASSOCIATED WITH A FRONTAL PASSAGE...MOST OF THIS RAIN OCCURRING IN
LESS THAN 2 HOURS. DUE TO THE SHORT DURATION OF THE HEAVY
RAINFALL...EXPECT RAPID RISES ALONG AREA STREAMS. AS LONG AS THE
RAINFALL AMOUNTS REMAIN BELOW 1.5 INCHES...FLOODING SHOULD BE KEPT
TO A MINIMUM.

ENSEMBLE FORECASTS SUGGEST THERE WILL ALSO BE SOME RESPECTABLE
RISES ON THE AREA RIVERS. 1.50 INCHES OF RAIN WILL CAUSE RIVERS
TO RISE TO NEAR BANKFULL. IF RAIN AMOUNTS EXCEED 1.50 INCHES OVER
ANY GIVEN BASIN...THEN RIVER FLOODING WOULD BECOME AN ISSUE.
ATTM...CURRENT FORECASTS REFLECT BASIN AVERAGE AMOUNTS CLOSER TO
1.25 INCHES.

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WIND ADVISORY FROM NOON WEDNESDAY TO MIDNIGHT EST WEDNESDAY
NIGHT FOR VAZ011-013-014-016>020-022>024-032>035-043>047-
058-059.
HIGH WIND WARNING FROM 4 AM WEDNESDAY TO MIDNIGHT EST
WEDNESDAY NIGHT FOR VAZ007-009-010-012-015.
NC...WIND ADVISORY FROM NOON WEDNESDAY TO MIDNIGHT EST WEDNESDAY
NIGHT FOR NCZ002>006-019-020.
HIGH WIND WARNING FROM 4 AM WEDNESDAY TO MIDNIGHT EST
WEDNESDAY NIGHT FOR NCZ001-018.
WV...WIND ADVISORY FROM NOON WEDNESDAY TO MIDNIGHT EST WEDNESDAY
NIGHT FOR WVZ043>045.
HIGH WIND WARNING FROM 4 AM WEDNESDAY TO MIDNIGHT EST
WEDNESDAY NIGHT FOR WVZ042.

$$
SYNOPSIS...AMS/RAB
NEAR TERM...AMS/DS
SHORT TERM...PM
LONG TERM...KK
AVIATION...DS/KK
HYDROLOGY...PM

AREA FORECAST DISCUSSION

NWS BLACKSBURG VA

701 PM EST TUE JAN 29 2013

.SYNOPSIS...
HIGH PRESSURE ALOFT WILL BUILD ACROSS THE EASTERN SEABOARD THROUGH
WEDNESDAY BRINGING UNSEASONABLY WARM TEMPERATURES TO THE AREA. A
STRONG COLD FRONT WILL MOVE THROUGH THE REGION LATE WEDNESDAY
ACCOMPANIED BY SHOWERS WITH GUSTY WINDS AND HEAVY RAIN. MUCH
COLDER TEMPERATURES WILL RETURN FOR THE END OF THE WEEK INTO THE
WEEKEND AS HIGH PRESSURE MOVES SOUTHEAST FROM CANADA. THERE WILL
BE SEVERAL CHANCES FOR LIGHT SNOW IN THE THURSDAY THROUGH SUNDAY
PERIOD.

.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 640 PM EST TUESDAY...
MADE SOME MINOR ADJUSTMENTS IN TEMPERATURES AND POPS TO REFLECT
CURRENT OBS AND MODEL TRENDS. 18Z NAM AND RUC STILL SHOWED
MOISTURE LIFTING NORTH ALONG THE SOUTHERN BLUE RIDGE TONIGHT.
APPEARS THAT TIMING MAY BE A LITTLE SLOWER. MORE ADJUSTMENTS LATER
TONIGHT.

AS OF 300 PM EST TUESDAY...

OVERNIGHT...SOUTHERLY FLOW WILL INCREASE ACROSS THE AREA IN ADVANCE
OF AN APPROACHING STRONG UPPER TROUGH AND ASSOCIATED COLD FRONT.
THIS WILL BRING ABUNDANT GULF OF MEXICO MOISTURE INTO THE REGION.
THE RESULT WILL INCREASING..THICKENING AND LOWERING OF THE CLOUD
COVER. ALL AREAS ARE EXPECTED TO BE CLOUDY BY EARLY WEDNESDAY
MORNING. LIGHT PRECIPITATION WILL DEVELOP BY MIDNIGHT...PRIMARILY
ALONG THE CREST OF THE BLUE RIDGE SOUTHWEST OF FLOYD VA INTO NW NC.
AFTER MIDNIGHT...THE FOCUS FOR THE BEST CHANCE OF RAIN WILL STILL BE
ALONG THE CREST OF THE BLUE RIDGE...HOWEVER...ALL PARTS OF THE
FORECAST AREA WILL HAVE AT LEAST A SLIGHT CHANCE.

BY SUNRISE WEDNESDAY...850 MB WINDS ARE EXPECTED TO HAVE A S-SW
ORIENTATION AND HAVE INCREASED TO AROUND 45 TO 55 KTS ACROSS THE
REGION AND MAINTAIN THESE SPEEDS...OR INCREASE A BIT MORE BY THE
AFTERNOON. BY THE OVERNIGHT SHIFT POSTED A HIGH WIND WIND WATCH FOR
THE AREA OF THE NORTHERN MOUNTAINS OF NORTH CAROLINA AND PARTS OF
THE MOUNTAIN EMPIRE REGION OF SOUTHWEST VIRGINIA BASED UPON HISTORY
OF WINDS OF A SIMILAR ORIENTATION AND SPEED YIELDING DAMAGING WINDS.
WE ARE UPGRADING THIS WATCH TO A WARNING...AND ADJUSTING THE START
AND END TIME EARLIER BY ONE HOUR TO BETTER MATCH THE HIGH WIND
WARNING BY GSP.

AS WEDNESDAY PROGRESSES...PRECIPITATION CHANCES WILL PROGRESSIVELY
INCREASE AS THE FRONT APPROACHES...AND THEN CROSSES THE AREA DURING
THE AFTERNOON. TRENDS OF THE LATEST MODEL GUIDANCE ARE ABOUT THREE
HOURS SLOWER WITH THE TIMING OF THE PASSAGE. AS SUCH...HAVE ADJUSTED
OUR POP AND WEATHER GRIDS ACCORDINGLY. WHEN THE FRONT MOVES THROUGH
THE AREA...WE ARE EXPECTING A STRONG SQUALL LINE OF SHOWERS WITH
LIMITED...IF ANY...THUNDER. THERE IS A CONCERN THAT SOME OF THE
STRONGER SHOWERS COULD HELP BRING HIGHER WINDS DOWN TO THE
SURFACE...AND BE POTENTIALLY DAMAGING. OUR OTHER CONCERN FROM WIND
INCLUDES GRADIENT PREVAILING WINDS IN ADVANCE OF THE FRONT. DURING
THE AFTERNOON AND EARLY EVENING HOURS...WIND GUSTS AT THE HIGHER
PEAKS ALONG AND WEST OF THE BLUE RIDGE...MAY SEE WIND GUSTS IN
EXCESS OF WIND ADVISORY CRITERIA...40 KTS. WE ARE REFLECTING THIS
CONCERN IN A WIND ADVISORY THAT WILL BE IN EFFECT FROM NOON
WEDNESDAY THROUGH MIDNIGHT.

TEMPERATURES WILL CONTINUE TO BE ON THE MILD SIDE TONIGHT AND
WEDNESDAY. LOWS TONIGHT IN THE MOUNTAINS WILL BE A MIX OF READINGS
AROUND 50 TO THE LOWER 50S. EAST OF THE BLUE RIDGE...LOW TO MID 50S
WILL BE COMMON. DESPITE ABUNDANT RAIN TOMORROW...WE ARE FORECASTING
LOW TO MID 60 IN THE MOUNTAINS AND UPPER 60S TO LOWER 70S ACROSS THE
PIEDMONT OF VIRGINIA AND NORTH CAROLINA.

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
AS OF 345 PM EST TUESDAY...

FRONTAL PASSAGE WEDNESDAY EVENING WILL BRING DRAMATIC CHANGE IN
TEMPERATURE...READINGS FALLING FROM THE 50S/60S WEDNESDAY EVENING
INTO THE 20S/30S DURING THE OVERNIGHT. SLUG OF FRONTAL PRECIP WILL
MOVE RAPIDLY EAST ACROSS THE CWA DURING THE EVENING WITH DOWNPOUR
OF RAIN PRODUCING UPWARDS OF AN INCH OF RAIN IN LESS THAN 2 HOURS
TIME. THIS BURST OF HEAVY RAINFALL WITH THE FRONTAL PASSAGE WILL
LIKELY RESULT IN SUDDEN RISES TO AREA STREAMS. WILL FORGO FLOOD
WATCH ATTM PER QUICK MOVEMENT OF SYSTEM AND LACK OF SUSTAINED
HEAVY RAIN THREAT. THAT SAID...STILL NOT A GOOD NIGHT TO BE
FLIRTING AROUND LOW WATER CROSSINGS.

.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 305 PM EST TUESDAY...

A LONG WAVE TROF REMAINS OVER THE EASTERN CONUS FOR THE WEEKEND. SFC
HIGH CENTERED ALONG THE CAROLINA COAST SATURDAY WILL MOVE EAST INTO
THE ATLANTIC OCEAN. A CLIPPER-LOW AND ATTENDING SURFACE COLD FRONT
APPROACHES FROM THE WEST SATURDAY AND TRAVELS ACROSS FORECAST AREA
SATURDAY NIGHT INTO SUNDAY MORNING. THE GFS SUGGEST THAT A COUPLE OF
INCHES OF SNOW ACCUMULATION IS POSSIBLE IN THE WESTERN UPSLOPE
AREAS. THE ECMWF HINTS AT LIGHTER SNOW TOTALS. KEPT SNOW SHOWERS IN
THE NORTHWEST UPSLOPE FLOW FOR SUNDAY MORNING INTO SUNDAY AFTERNOON
LEANING TOWARDS GFS THEN TAPER OFF AS THE TROF AXIS MOVES FURTHER
INTO THE ATLANTIC. HIGH PRESSURE BUILDS ACROSS THE REGION SUNDAY
NIGHT INTO MONDAY MORNING. ANOTHER LOW PRESSURE CENTER LIFTS
NORTHEAST ACROSS GREAT LAKES AND PUSHES A COLD FRONT TOWARDS OUR
REGION MONDAY. THE COLD FRONT ADVANCES ACROSS OUR REGION MONDAY
NIGHT INTO TUESDAY. THE GFS DEVELOPS A LOW PRESSURE CENTER OFF THE
VIRGINIA COAST MONDAY NIGHT AND LIFTS IT NORTHWARD ON TUESDAY. THE
GFS SOLUTION INDICATED THAT MORE SNOW...SEVERAL INCHES ARE POSSIBLE
IN THE WESTERN UPSLOPE AREAS ON MONDAY NIGHT INTO TUESDAY. WENT WITH
SCATTERED POPS FOR MONDAY NIGHT INTO TUESDAY AND WILL WATCH FOR
FURTHER RUNS TO SEE EVOLUTION AND DETAILS OF THIS STORM FOR EARLY
NEXT WEEK.

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
AS OF 635 PM EST TUESDAY...

ENSEMBLE FORECASTS SUGGEST THERE WILL ALSO BE SOME RESPECTIBLE
RISES ON THE AREA RIVERS. 1.50 INCHES OF RAIN WILL CAUSE RIVERS
TO RISE TO NEAR BANKFULL. IF RAIN AMOUNTS EXCEED 1.50 INCHES OVER
ANY GIVEN BASIN...THEN RIVER FLOODING WOULD BECOME AN ISSUE.
ATTM...CURRENT FORECASTS REFLECT BASIN AVERAGE AMOUNTS CLOSER TO
1.25 INCHES.

.CLIMATE...
RECORD HIGH TEMPERATURES AND YEAR ESTABLISHED FOR JAN 29.

BLACKSBURG VA...68 IN 2013 (TIED) OLD RECORD WAS 68 IN 1975
BLUEFIELD WV....68 IN 2013 (BROKE) OLD RECORD OF 64 IN 2002
DANVILLE VA.....76 IN 2002
LYNCHBURG VA....75 IN 1975
ROANOKE VA......75 IN 1975

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WIND ADVISORY FROM NOON WEDNESDAY TO MIDNIGHT EST WEDNESDAY
NIGHT FOR VAZ011-013-014-016>020-022>024-032>035.
HIGH WIND WARNING FROM 6 AM WEDNESDAY TO MIDNIGHT EST
WEDNESDAY NIGHT FOR VAZ007-009-010-012-015.
NC...WIND ADVISORY FROM NOON WEDNESDAY TO MIDNIGHT EST WEDNESDAY
NIGHT FOR NCZ002-003-019.
HIGH WIND WARNING FROM 6 AM WEDNESDAY TO MIDNIGHT EST
WEDNESDAY NIGHT FOR NCZ001-018.
WV...WIND ADVISORY FROM NOON WEDNESDAY TO MIDNIGHT EST WEDNESDAY
NIGHT FOR WVZ043>045.
HIGH WIND WARNING FROM 6 AM WEDNESDAY TO MIDNIGHT EST
WEDNESDAY NIGHT FOR WVZ042.

$$
SYNOPSIS...RAB
NEAR TERM...DS
SHORT TERM...PM
LONG TERM...KK
AVIATION...DS/KK
HYDROLOGY...
CLIMATE...

AREA FORECAST DISCUSSION

NWS BLACKSBURG VA

638 PM EST TUE JAN 29 2013

.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 300 PM EST TUESDAY...

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
AS OF 345 PM EST TUESDAY...

FRONTAL PASSAGE WEDNESDAY EVENING WILL BRING DRAMATIC CHANGE IN
TEMPERATURE...READINGS FALLING FROM THE 50S/60S WEDNESDAY EVENING
INTO THE 20S/30S DURING THE OVERNIGHT. SLUG OF FRONTAL PRECIP WILL
MOVE RAPIDLY EAST ACROSS THE CWA DURING THE EVENING WITH DOWNPOUR
OF RAIN PRODUCING UPWARDS OF AN INCH OF RAIN IN LESS THAN 2 HOURS
TIME. THIS BURST OF HEAVY RAINFALL WITH THE FRONTAL PASSAGE WILL
LIKELY RESULT IN SUDDEN RISES TO AREA STREAMS. WILL FORGO FLOOD
WATCH ATTM PER QUICK MOVEMENT OF SYSTEM AND LACK OF SUSTAINED
HEAVY RAIN THREAT. THAT SAID...STILL NOT A GOOD NIGHT TO BE
FLIRTING AROUND LOW WATER CROSSINGS.

.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 305 PM EST TUESDAY...

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
... AS OF 635 PM EST TUESDAY...

.CLIMATE...
RECORD HIGH TEMPERATURES AND YEAR ESTABLISHED FOR JAN 29.

$$
SYNOPSIS...RAB
NEAR TERM...DS
SHORT TERM...PM
LONG TERM...KK
AVIATION...DS/KK
HYDROLOGY...
CLIMATE...

AREA FORECAST DISCUSSION

NWS BLACKSBURG VA

1121 PM EST SUN JAN 27 2013

.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFFSHORE OVERNIGHT ALLOWING AN UPPER
LEVEL DISTURBANCE TO CROSS THE AREA...TRIGGERING PERIODS OF
RAIN AND FREEZING RAIN INTO EARLY MONDAY. UPPER LEVEL RIDGING
BUILDING ACROSS THE AREA THROUGH THE EARLY PART OF THE WEEK WILL
RESULT IN AN UNSEASONABLE WARMUP ACROSS THE AREA. A STRONG COLD
FRONT WILL MOVE INTO THE REGION BY MID-WEEK...BRINGING WIDESPREAD
MODERATE RAINFALL FOLLOWED BY A RETURN TO WINTERLIKE TEMPERATURES.

.NEAR TERM /THROUGH MONDAY/...
AS OF 845 PM EST SUNDAY...

SOUNDINGS CONTINUE TO SHOW QUITE A BIT OF DRY AIR BELOW 7H THIS
EVENING WITH ONLY WEAK RETURN FLOW IN THE LOWEST LEVELS WHERE
DEWPOINTS REMAIN IN THE 20S. PRECIP ATTEMPTING TO MOVE IN FROM THE
WEST HAS CONTINUED TO WEAKEN UPON ENCOUNTERING THIS DRY POCKET AND
WILL STILL TAKE SEVERAL HOURS FOR BETTER MOISTENING TO OCCUR FROM
WEST TO EAST OVERNIGHT. LATEST SHORT TERM MODELS CONTINUE TO
INDICATE THE MAJORITY OF THE PRECIP TO RUN ALONG AND NORTH OF
HIGHWAY 460 WITH ONLY THE HRRR AT BIT MORE AGRESSIVE IN SLIDING A
A SWATH OF LIGHT QPF ACROSS MOST OF THE CWA BY DAYBREAK. HOWEVER
DO THINK THAT THE FAR NW COULD SEE A LITTLE MORE QPF SO UPPED ICE
TOTALS A LITTLE ACROSS THE COLDER SECTIONS OF THE GREENBRIER
VALLEY EAST INTO THE HIGHLANDS AND SOUTHERN SHENANDOAH VALLEY PER
THE LATEST 00Z NAM. SOUTH OF THAT AREA...QUITE A BIT OF
UNCERTAINTY REMAINS IN JUST HOW MUCH PRECIP WILL BE OBSERVED SINCE
SEEING A NICE DRY SLOT WITH THE UPPER JET BEHIND THE INITIAL BAND
NOW IN FAR SW VA WHICH COULD SPLIT THE PRECIP...PER LATEST RAP SO
SOMETHING TO WATCH. HOWEVER DOES APPEAR THAT THE NW NC MOUNTAINS
COULD SEE A LITTLE MORE ICE EARLY ON GIVEN CURRENT RADAR TRENDS SO
BOOSTED ICE AMOUNTS THERE SLIGHTLY AS WELL. OTRW SURFACE TEMPS
STILL REMAIN WELL ABOVE FREEZING WEST OF I-77 IN VIRGINIA SO WONT
INCLUDE ANY ADDED CTYS OVERNIGHT. DID ADJUST POPS TO MATCH TIMING
A BIT BETTER WITH ONLY SLIGHT ADJUSTS TO TEMPS AS EXPECT DEWPTS TO
RISE SOME AS EVAPORATIVE COOLING DEVELOPS BEFORE ANY PRECIP
ACTUALLY REACHES THE SURFACE OUTSIDE OF THE HIGHER SW RIDGES.

BY LATE MORNING...TEMPERATURES ARE EXPECTED TO RISE ABOVE
FREEZING AS THE WARMER AIR ALOFT WORKS ITS WAY TO THE
SURFACE...ALTHOUGH DEEPER AREAS OF THE GREENBRIER VALLEY...THE
SOUTHERN SHENANDOAH VALLEY...THE NEW RIVER VALLEY...AND PARTS OF
THE ROANOKE VALLEY MAY TAKE A LITTLE LONGER TO WARM. MONDAY
AFTERNOON TEMPERATURES ARE EXPECTED TO RISE INTO THE UPPER 40S TO
THE LOW 50S FOR MOST OF THE AREA.

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 300 PM EST SUNDAY...

ROLLER-COASTER WEATHER THIS PERIOD. WARMING UP TO ABOVE NORMAL TEMPS
AS 5H RIDGE BUILDS OVER THE EASTERN U.S. IN ADVANCE OF A DEEPENING
TROUGH OVER THE ROCKIES. THIS TROUGH PROGRESSES SLOWLY EAST TO THE
PLAINS STATES TUESDAY NIGHT AND BROADENS OUT AS IT ARRIVES IN OUR
AREA WEDNESDAY NIGHT.

AHEAD OF THIS TROUGH SW FLOW WILL KEEP SMALL THREAT OF SHOWERS
AROUND MONDAY NIGHT OVER THE NWRN CWA WITH SOME WEAK UPSLOPE. THE
PATTERN...WET GROUND...AND FORECAST SOUNDINGS SUGGEST POTENTIAL FOR
DENSE FOG EVENT...BUT WILL ADD AREAS OF FOG IN LATE. WINDS ARE
EXPECTED TO BE UP ENOUGH WHERE SOME AREAS COULD HAVE FOG BUT NOT
DENSE. MAIN IMPACT AREA SEEMS TO BE THE PIEDMONT PER THE LATEST SREF
PROBABILITIES FOR VSBYS LESS THAN 1SM.

ANY FOG WILL BE ERODING TUESDAY AS THIS SHOULD BE OUR WARMEST
DAY...UNLESS THE FRONTAL TIMING AND PRECIP SLOW DOWN WEDNESDAY.
HIGHS TUESDAY WILL BE IN THE LOWER 60S MOST LOCATIONS. COULD SEE A
RECORD HIGH AT BLF AS 63F IS FORECAST AND THE RECORD IS 64 SET IN
2002. SKIES SHOULD BE PARTLY TO MOSTLY SUNNY TUESDAY.

WILL SEE INCREASING DEWPOINTS AND PRECIP CHANCES HEADING INTO
TUESDAY NIGHT AHEAD OF THE COLD FRONT. WINDS ARE GOING TO INCREASE
AS WELL LATE OVER THE MTNS. THE LOW LVL FLOW SUGGESTS THAT THE MTN
EMPIRE AREA WILL NOT BE IN THE TYPICAL FAVORED SSE FLOW FOR HIGH
WINDS...BUT THIS SYSTEM APPEARS STRONG ENOUGH GIVEN MODELS
PROJECTING A 50-60 KNOT JET AT 8H ARRIVING OVERHEAD BY 12Z
WEDNESDAY. GIVEN SUCH STRONG WARM ADVECTION AND INCREASE IN CLOUDS
WENT MILD TUESDAY NIGHT WITH LOWS IN THE 50S HIGHER
ELEVATIONS...PIEDMONT AND URBAN AREAS WITH 40S ACROSS THE VALLEYS.

THE SYSTEM IS VERY DYNAMIC AND WIND DRIVEN AND SPC HAS US IN AN
OUTLOOK FOR POTENTIAL SEVERE WEATHER WEDNESDAY. ON THE SIDE FAVORING
SEVERE IS THE WIND ENERGY WITH 70+ KNOT LLJ MOVING FROM TN/OH VALLEY
WED MORNING TO DELMARVA AT 18Z WED...WITH SECONDARY WIND MAX PUSHING
FROM UPSTATE SC TO ERN VA IN THE AFTERNOON. SHEAR IS TOP OF THE
CHARTS PER HODOGRAPHS. CONDITIONS INHIBITING SVR ARE WEAK LAPSE
RATES...LOTS OF CLOUDS/RAIN AND LITTLE IF ANY CAPE.

HOWEVER...CONFIDENT THAT THIS WILL BE A CASE WHERE SOME OF THE
SHOWERS ALONG THE FRONT BRING DOWN GUSTS OVER 50 MPH OR
MORE...SIMILAR TO SOME OF THE EVENTS WE GET IN LATE FEB-
MARCH...WHERE THUNDER IS LIMITED. ADDED THUNDER AND GUSTY WINDS FOR
NOW TO THE FORECAST IN THE MTN EMPIRE/SE WV INTO NW NC BY MIDDAY
WEDNESDAY AND OUT EAST IN THE AFTN.

THE 12Z ECMWF HAS COME IN SLOWER WITH THE FRONT AND THIS MAY BE THE
CASE GIVEN THE AMPLIFIED PATTERN. THIS MAY NEED TO ADJUSTED LATER
SHIFTS...AS FOR NOW WILL HAVE THE HIGHEST THREAT OF RAIN IN THE LATE
MORNING TO AFTN TIME FRAME...EXITING WED NIGHT.

THIS WILL AFFECT HIGHS SOMEWHAT BUT KEPT IN THE PIEDMONT WARM WITH
TEMPS IN THE MID 60S WITH MID 50S TO NEAR 60 WEST.

STRONG COLD AIR ADVECTION PUSHES IN WED NIGHT AS 8H TEMPS CRASH FROM
+10C WED AFTN TO -5 TO -8C LATE WED NIGHT.

MOISTURE STAYS IN THE WRN COUNTIES THROUGH THE NIGHT WHERE RAIN
CHANGES TO SNOW SHOWERS. WILL MORE THAN LIKELY SEE SOME WIND
ADVISORY CRITERIA...ALTHOUGH MODELS ONLY SHOW 35-40 KTS AT 8H.

TEMPS WED NIGHT SHOULD DROP INTO THE MID 20S WEST TO UPPER 30S
EAST...ALTHOUGH MAY STAY WARMER IF SYSTEM SLOWS DOWN AND THE
CLOUDS/WIND DESPITE THE CAA KEEP TEMPS MORE ELEVATED LONGER.

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 300 PM EST SUNDAY...

COLD FRONT WILL CONTINUE TO MARCH EAST INTO THE ATLANTIC OCEAN
THURSDAY. STRONG CAA BEHIND THE FRONT WILL RESULT IN TEMPERATURES
THURSDAY SIGNIFICANTLY COLDER THAN WEDNESDAY...WITH READINGS FROM
AROUND 30 DEGREES IN THE NORTHWEST TO THE UPPER 40S IN THE
SOUTHEAST. GUSTY NORTHWEST WINDS IN THE WAKE OF THE COLD FRONT WILL
RESULT IN RAIN AND SNOW SHOWERS CHANGING TO SNOW SHOWERS AND SNOW
FLURRIES. ANOTHER REINFORCING SHOT OF COLD AIR SHOULD ARRIVE
THURSDAY NIGHT INTO FRIDAY. THE SHORTWAVE ROTATING AROUND THE TROUGH
LOOKED MORE ROBUST ON ECMWF THAN THE GFS. LOW TEMPERATURES THURSDAY
NIGHT WILL BE SEASONABLY COLD WITH VALUES FROM THE TEENS IN THE
NORTHWEST MOUNTAINS TO THE MID 20S IN THE SOUTHEAST. FRIDAY INTO
FRIDAY NIGHT...ANTICIPATE THAT SNOW SHOWERS WILL TAPER OFF OR END AS
HIGH PRESSURE BUILDS IN FROM THE WEST. KEEP YOUR WINTER COATS READY
ON FRIDAY WITH HIGHS FROM THE LOWER 20S IN THE NORTHWEST TO AROUND
40 IN THE SOUTHEAST. THE HIGH CENTER BUILDS OVERHEAD FRIDAY NIGHT
INTO SATURDAY MORNING. FRIDAY NIGHT LOWS WILL VARY FROM THE SINGLE
DIGITS TO THE LOWER 20S IN THE SOUTH. THE HIGH CENTER MARCHES EAST
TO THE CAROLINA COAST ON SATURDAY...ALLOWING ANOTHER COLD FRONT TO
APPROACH FROM THE WEST. THE COLD FRONT TRAVELS EAST AND REACHES THE
MOUNTAINS SATURDAY NIGHT INTO SUNDAY MORNING. AS THE TROF AXIS
MOVES INTO THE ATLANTIC...HIGH PRESSURE SETTLES OVER THE SOUTHEAST
ON SUNDAY.

.AVIATION /04Z MONDAY THROUGH FRIDAY/...
AS OF 1105 PM EST SUNDAY...

DRY AIR SLOWLY GIVING WAY FROM WEST TO EAST ATTM AS THE INITIAL
BATCH OF -RA/-FZRA MOVES ACROSS THE WESTERN MOUNTAINS AND SHOULD
ARRIVE ALONG THE BLUE RIDGE SHORTLY AFTER MIDNIGHT. THIS BAND OF
PRECIP SHOULD FINALLY MOISTEN THE COLUMN ENOUGH TO ALLOW CIGS TO
LOWER TO LOW END VFR OR HIGH MVFR LEVELS FROM WEST TO EAST DURING
THE NEXT FEW HOURS. PRECIP INITIALLY IN THE FORM OF -RA WILL
IMPACT KBLF IN THE NEXT HOUR AND THEN LIKELY SWITCH TO A MIX OF
-RA/-FZRA AS SURFACE TEMPS COOL. THE LIGHT MIX SHOULD ALSO WORK
INTO THE KLWB VICINITY BETWEEN MIDNIGHT AND 1 AM RESULTING IN
PERIODS OF -FZRA INTO THE PREDAWN HOURS OF MONDAY.

OTRW THE UPSTREAM WARM FRONT WILL SLIDE BY TO THE NW OVERNIGHT
WITH LIGHT PRECIP ARCING FAR ENOUGH SE TO CLIP MUCH OF THE REST
OF THE REGION OVERNIGHT. ASSOCIATED PTYPE LOOKS TO BE MAINLY
FREEZING RAIN THOUGH QPF AMOUNTS SHOULD BE RELATIVELY LIGHT. KDAN
APPEARS TO BE ON THE SOUTHERN EXTENT OF THE PRECIP AND MAY MISS
OUT ON SEEING MUCH AT ALL. ELSW STILL EXPECTING A PERIOD OF LIGHT
MIX ROUGHLY IN THE 05Z TO 13Z TIME FRAME WITH THE MAJORITY
SWINGING THROUGH THE KLWB VICINITY...WITH LESS SOUTH OF A KLYH-
KROA- KBCB LINE EARLY MONDAY. EXPECT TEMPS MAY NUDGE UP JUST
ENOUGH ABOVE FREEZING TO CAUSE LOCATIONS SUCH AS KBLF TO SWITCH
BACK TO JUST RAIN BEFORE TAPERING MID MORNING MONDAY AS WELL. OTRW
KEEPING IT MAINLY -FZRA FOR NOW. CIGS AND VSBYS SHOULD ALSO BE
LOWEST ACROSS THE NORTH WHERE MOISTURE WILL BE DEEPER SO CANT RULE
OUT A PERIOD OF IFR AT KLWB...WHILE EXPECTING A PERIOD OF MOSTLY
MVFR LEVEL CLOUD BASES ELSW FOR NOW INTO MONDAY MORNING.

SHOULD SEE CONDITIONS IMPROVE BEHIND THE EXITING PRECIP MIDDAY
MONDAY BEFORE CIGS LOWER AGAIN IN THE AFTERNOON WITH MOISTURE AND
WEAK IMPULSES SLIDING AROUND THE DEVELOPING UPPER RIDGE. THIS
COULD RESULT IN ANOTHER PERIOD OF -RA/-SHRA AT BOTH KBLF/KLWB
MONDAY AFTERNOON. DESPITE INCREASING SW FLOW APPEARS LOW LEVEL
MOISTURE WILL BE SLOW TO EXIT MONDAY NIGHT WITH THE POTENTIAL FOR
IFR IN LOW CIGS AND PERHAPS A FEW LEFTOVER -SHRA MAINLY SE WVA
SITES MONDAY EVENING.

DRYING CONDITIONS CAN BE EXPECTED TUESDAY AND WILL SEE A BRIEF
PERIOD OF IMPROVED FLYING WEATHER AHEAD OF A STRONG COLD FRONT
INTO TUESDAY NIGHT...WITH VFR/MVFR EXPECTED UNTIL THE FRONT AND
ITS ASSOCIATED PRECIP SHIELD ARRIVES WEDNESDAY. THIS FRONT MAY
BRING PERIODS OF MODERATE TO HEAVY RAIN ALONG WITH AN ISOLATED
THUNDERSTORM AND GUSTY WINDS TO PARTS OF THE REGION MIDWEEK. THIS
FRONT WILL BE FOLLOWED BY ANOTHER SHOT COLD AIR INCLUDING WINDY
CONDITIONS AND UPSLOPE MVFR CIGS WITH -SHSN AT KBLF/KLWB WEDNESDAY
NIGHT INTO THURSDAY. ANOTHER FAST MOVING WEAK DISTURBANCE MAY
BRING THE NEXT ROUND OF MAINLY MOUNTAIN -SHSN ALONG WITH MVFR CIGS
ON FRIDAY.

DUE TO THE MISSING OBSERVATION FROM KBCB...INCLUDING AMD NOT SKED
FOR THE TAF FORECAST THERE GIVEN UNCERTAINTY IN UPCOMING CIGS AND
VSBYS AS PRECIP ARRIVES OVERNIGHT.

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FREEZING RAIN ADVISORY UNTIL 10 AM EST MONDAY FOR VAZ010>020-
022>024-032>035-043>047-058-059.
NC...FREEZING RAIN ADVISORY UNTIL 10 AM EST MONDAY FOR NCZ001>006-
018>020.
WV...FREEZING RAIN ADVISORY UNTIL 10 AM EST MONDAY FOR WVZ042>045.

$$
SYNOPSIS...NF
NEAR TERM...JH/NF
SHORT TERM...WP
LONG TERM...KK
AVIATION...JH/MBS/NF

AREA FORECAST DISCUSSION

NWS SPOKANE WA

254 PM PST Tue Jan 29 2013

.SYNOPSIS...
The weather pattern will remain active and wintry through Thursday
as a number of storm systems will result in periodic heavy snow
accumulations...another extended snow event looks likely for the
region with the focus of the heavier snow again for the higher
terrain of the Central Idaho Panhandle...the Blue mountains and
the Camas Prairie. High pressure will build into the region at the
end of the work week and linger into the weekend with fog and low
stratus expected across much of the basin and in the valleys.

.DISCUSSION...

...ANOTHER ROUND OF MODERATE TO LOCALLY HEAVY SNOW EXPECTED
TONIGHT INTO EARLY WEDNESDAY ACROSS PORTIONS OF THE CENTRAL IDAHO
PANHANDLE AND EXTREME SOUTHEAST WASHINGTON...

Tonight through Wednesday...Winter weather system number three
will be the main focus during this period. This is the latest
system to ride down into the Inland NW via swift northwest flow
aloft. This system will be the most moisture laden of the three
and thus will likely produce the greatest amounts of
precipitation. However unlike the last couple systems...this one
should be the warmest as well...so snowfall totals and snow ratios
will likely under-perform the previous events.

Looking at the latest water vapor satellite pictures there was a
well defined plume of moisture wrapping over the top of the ridge
and pushing into the southern third of British Columbia. This
plume is expected to shift southeast overnight as it encroaches on
the eastern flank of the strong eastern Pacific ridge axis. As the
moisture tracks into the forecast area we should see increasing
clouds and a rapid increase in precipitation. Just like last
night...the bulk of the precipitation will focus over the SE
corner of Washington and the central Idaho Panhandle. For these
locations we have forecast anywhere from 0.25-0.50 inches of
precipitation. If snow levels were close to what they have been
over the past few nights...we`d be looking at widespread snowfall
reports of 3-7 inches across portions of the Camas Prairie...Idaho
Palouse...Blue Mountains...and central Idaho Panhandle Mountains
with locally heavier amounts possible over NW facing slopes.
However...temperatures are considerably warmer than they have
been. Down on the Palouse and Lewiston area...the 24 hour
departure is about 5 degrees warmer. This wouldn`t be important if
we had dry air entrenched in the lower atmosphere, but that`s not
the case...as wet-bulb temperatures in that region were generally
right around freezing on the Palouse...and in the mid 30s around
Lewiston. That will prove critical...as we won`t see a lot of
cooling this evening with the skies clouding up so rapidly. Also
SW winds will be increasing through the boundary layer up to 850
mbs which should keep the wet-bulb temperatures steady if not
cause them to slowly rise. Thus we expect a much smaller area to
be impacted by the significant snows tonight into Wednesday
morning. We have decided to issue another batch of winter weather
highlights with advisories for the Idaho Palouse (mainly above
2500-3000 ft), the Camas Prairie (also above 3000 ft), and Blue
Mountains (above 4000 ft). Snow amounts will range from 2-5" on
the Idaho Palouse...3-7" on the Camas Prairie and locally heavier
amounts over the Blue Mountains. As for valley locations...the
southern half of the central Idaho Panhandle should receive the
heaviest snow amounts. Locations such as Deary...Bovill...Clarkia
could see amounts ranging from 4-7" and for this reason we will
issue a winter storm warning. Some of this snow should be blown
about by moderate westerly winds at least over exposed locations.

For the remainder of the forecast area...the event will be a
rather minor one as swift moving NW flow systems generally
underwhelm from a precipitation standpoint, especially when
considering there is nary a significant surface or 850 mb low. And
this should be the case once again. So although locations across
the eastern Columbia Basin...Spokane area...NE Washington and the
north Idaho Panhandle should see some snow...amounts should be
rather light and unimpressive. fx

Wednesday night through Friday night...Long-wave ridge axis
remains placed off the coast which continues to favor a flow from
the northwest for storm system to utilize until Friday. Any
disturbances that drop down the east edge of this long-wave ridge
orienting the northwest flow gets its moisture tap weakened by
passing through the long-wave ridge itself limiting moisture
availability. There is not much instability to work nor is there
any significant cold air damming in most of the lowlands as well
so with all these things in mind pops and QPF will remain marginal
and favor the extreme western edge of the Cascade Crest along with
extreme Northeast Washington and the Northern Idaho Panhandle.
Remaining locations especially those in the lowlands such as the
Columbia Basin and vicinity will have substantially lower pops
with low to no QPF mention for much of this interval as well.
Storm track interrupted with Shortwave ridging for Friday night
allows for a dry forecast with perhaps some inversions developing
as the low level flow favors a warmer trajectory from the
southwest. Perhaps this may be a night suitable for fog and low
cloud formation for lowlands and valleys. Forecast temperatures
show a loose warming trend in daytime highs but overnight lows
will be noisy as disturbance passage from northwest brings cooler
air-mass down and shortwave ridging Friday night allows for
inversions which may allow for warmer mid-slope temperatures
compared to lowlands and valleys and this would just as loosely
translate to snow levels as well. /Pelatti

Saturday through Tuesday: High confidence in a high pressure ridge
to build in over the region this weekend. The ridge will result
in weak winds and large scale subsidence with widespread stratus
and patchy fog across the region. Boundary layer winds will be out
of the east down the Palouse on Saturday. Fog and stratus will more
likely burn off across this area and will be pushed up against the
northern mountains of eastern WA and up against the east slopes of
the Cascades. Models are in good agreement with a weakening
shortwave pushing in to this ridge Saturday night into Sunday.
This wave looks to split apart with the bulk of the energy diving
southward and forming a closed low off of the southern California
coastline and Baja California. The northern branch of this trough
will quickly push across the region, but models are not showing
much dynamics after it splits and does not look to play a big
factor in our weather.

Models become more uncertain after this period as far as when the
ridge will actually break down. The operational runs of the GFS
and the ECMWF are in fairly good agreement with each other in
showing the ridge re-amplifying after the passage of the weak wave
on Sunday. 500 mb pressure patterns continue to show an amplifying
pattern over the west coast as low pressure in the Gulf of Alaska
digs down the western coastline. This would result in a slower
break down of the ridge over the area. The Canadian model shows a
flatter ridge or more moist zonal flow pattern heading into early
next week. The GEFS ensemble mean is more reflective of a quicker
break down of the ridge. However, there is a large spread in the
individual ensemble members of the GEFS. Due to this uncertainty, I
did not make much in the way of changes to the forecast, which
follows a slower break down of the ridge more toward Tuesday and
Tuesday night. I did keep a mention of the possibility of
precipitation in the mountains for Sunday through Monday night
with the GEFS ensemble mean showing a fast break down of the
ridge. We will be on the warm side of the jet stream with 850 mb
winds out of the southwest. The southwest orientation will likely
advect up warmer temperatures, so snow levels are expected to be
above valley floors when the first wave of moisture moves through.

Temperatures this weekend will have little diurnal variability
across the western basin and in the surrounding valleys where
stratus is most likely. There is more uncertainty with stratus
coverage in early next week and temperatures will be dependent on
this cloud cover; however, I generally went with warming daytime
temperatures with warm air advection at low to mid levels. /SVH

.AVIATION...
18Z TAFS: main trouble spots this morning are along the KGEG-KCOE
corridor due to areas of stratus and IFR cigs. Feel confident that
these should be mainly gone before 20-21z...with VFR conditions
after that. All remaining sites should be VFR through the daytime
hours. For tonight...the next winter system will come into play.
The latest HRRR has delayed the onset of the pcpn until aft 04z
for all sites xcp MWH and EAT. Feel confident that the pcpn will
be -sn for all sites xcp LWS and that IFR conditions will ensue
shortly after the onset of pcpn. Looks like the eastern sites
should see abt 6hrs of pcpn...aft which the main concern will be
widespread stratus and fog. MOS guidance is suggesting IFR
conditions for all the eastern sites and we have generally
followed suit. fx

.PRELIMINARY POINT TEMPS/POPS...
Spokane 29 38 30 36 27 36 / 70 20 30 40 20 10
Coeur d`Alene 29 38 31 36 28 36 / 70 30 50 70 40 20
Pullman 32 38 33 39 30 38 / 90 60 70 60 30 10
Lewiston 37 47 37 46 33 45 / 90 50 70 60 30 10
Colville 27 37 30 41 27 40 / 70 20 20 30 30 10
Sandpoint 29 36 28 36 28 36 / 70 40 60 70 60 20
Kellogg 28 36 30 39 29 38 / 100 90 80 80 70 50
Moses Lake 29 41 29 41 27 40 / 20 10 10 10 10 10
Wenatchee 30 38 29 39 27 39 / 10 0 10 10 10 10
Omak 25 35 24 36 25 35 / 40 10 10 10 10 10

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory from 7 PM this evening to 10 AM PST
Wednesday for Idaho Palouse.

Winter Storm Warning from 7 PM this evening to Noon PST
Wednesday for Central Panhandle Mountains.

Winter Weather Advisory from 7 PM this evening to 10 AM PST
Wednesday for Lewis and Southern Nez Perce Counties.

WA...Winter Weather Advisory from 7 PM this evening to 10 AM PST
Wednesday for Northeast Blue Mountains.

AREA FORECAST DISCUSSION

NWS LA CROSSE WI

1200 PM CST MON JAN 28 2013

.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT
344 AM CST MON JAN 28 2013

NUMEROUS FORECAST CONCERNS:
1. DENSE FOG THIS MORNING
2. TEMPERATURES THROUGH TUESDAY
3. POTENTIAL FOR FREEZING RAIN/DRIZZLE TONIGHT
4. POTENTIAL FOR MORE DENSE FOG TONIGHT.
5. THUNDERSTORM POTENTIAL TONIGHT/TUESDAY
6. POSSIBLY ANOTHER INTERESTING SYSTEM FOR TUESDAY NIGHT/WEDNESDAY

CURRENTLY AS OF 09Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED TROUGHING OVER THE WESTERN U.S....RIDGING OVER THE EASTERN
TWO THIRDS OF THE U.S....WITH A SHORTWAVE TOPPING THIS RIDGING
STRETCHED ACROSS WESTERN WI. THIS SHORTWAVE WAS THE ONE RESPONSIBLE
FOR BRINGING MUCH OF THE WINTRY PRECIPITATION YESTERDAY TO THE
FORECAST AREA. THIS PRECIPITATION HAS NOW SHIFTED NORTH INTO UPPER
MICHIGAN. STILL DEALING WITH SOME DRIZZLE/FREEZING DRIZZLE...BUT
MUCH OF THIS HAS MOVED OFF TO THE EAST INTO EASTERN WISCONSIN.
PLENTY OF LOW CLOUDS REMAIN DUE TO TRAPPED LOW LEVEL MOISTURE BELOW
A SUBSIDENCE INVERSION PRODUCED BY THE SHORTWAVE. 00Z DVN AND OAX
SOUNDINGS ARE MOST REPRESENTATIVE OF THIS TRAPPED LOW LEVEL
MOISTURE. THE RECENT PRECIPITATION INTO THE COOL AIRMASS THAT
PRE-EXISTED THE PRECIPITATION...COMBINED WITH A WEAKENING PRESSURE
GRADIENT ASSOCIATED WITH A SURFACE LOW NOW IN NORTHEAST IOWA...HAS
RESULTED IN AN EXPANSION OF DENSE FOG FROM OMAHA NE NORTHEAST INTO
THE SOUTHERN HALF OF THE FORECAST AREA. SOUTH OF THIS LOW PRESSURE
AREA...TEMPERATURES CLIMB WELL INTO THE 30S AND EVEN UPPER 40S
ACROSS SOUTHERN IOWA. FARTHER SOUTH...TEMPERATURES AND DEWPOINTS ARE
IN THE 50S ACROSS MISSOURI. NORTH OF THE LOW...TEMPERATURES ARE
HOLDING NEAR OR JUST BELOW FREEZING. OTHER NOTES...A LARGE AREA OF
DRY AIR IS NOTED FROM NORTHERN MEXICO INTO THE FORECAST AREA ON
WATER VAPOR. DESPITE THIS UPPER LEVEL DRY AIR...00Z PRECIPITABLE
WATER PLOT FROM SOUNDINGS SHOWED 0.7-1.1 INCH READINGS FROM THE
TEXAS GULF COAST NORTH TO THE FORECAST AREA...ANYWHERE FROM 200-330
PERCENT OF NORMAL. TO THE WEST...LOW PRESSURE HAS BEEN FORMING OVER
NORTHEAST COLORADO DOWNSTREAM OF THE WESTERN TROUGH. PRETTY POTENT
SHORTWAVE TOO AT THE BASE OF THE TROUGH IN SOUTHERN CALIFORNIA.

TODAY...MUCH OF THE DAY WILL FEATURE SUBSIDENCE IN THE WAKE OF THE
SHORTWAVE THAT BROUGHT THE WINTRY MIX YESTERDAY. HIGH PRESSURE
SHOULD BUILD IN TOO IN THE WAKE OF THE SURFACE LOW CURRENTLY IN
NORTHEAST IOWA. THUS...ANTICIPATING A DRY DAY. THERE ARE A COUPLE
FORECAST ISSUES...THOUGH. FIRST IS THE CLOUDS. THERE ARE SOME HINTS
IN THE 28.00Z NAM/GFS SOUNDINGS THAT THE CLOUDS MAY TRY TO BREAK UP
SOMEWHAT DURING THE AFTERNOON. THE CAUSE IS A COMBINATION OF
PERSISTENT DEEP LAYER SUBSIDENCE AND DIURNAL MIXING. ALTHOUGH LIGHT
WINDS ARE A PROBLEM FOR MIXING OUT THE CLOUDS...FEEL THE
AFOREMENTIONED TWO REASONS SOUND REASONABLE TO MENTION SOME CLEARING
IN THE FORECAST. THIS PARTIAL CLEARING COMBINED WITH 925MB TEMPS
PROGGED AT 18Z IN THE -2C NORTH TO +2C SOUTH SHOULD ALLOW
TEMPERATURES TO CLIMB INTO THE MID 30S NORTH TO LOW 40S SOUTH. THE
NEXT CONCERN IS THE MORNING FOG. HAVE ISSUED A DENSE FOG ADVISORY TO
COVER THE LIGHT WINDS AND RECENT MOISTURE...VALID TIL NOON. IT MAY
BE EXPANDED FURTHER NORTHEAST. ASSUMING THE BREAKS IN THE CLOUDS
DEVELOP AS PLANNED...THE DENSE FOG ADVISORY END TIME OF NOON SHOULD
WORK OUT.

TONIGHT...MODELS ALL SHOW THAT THE POTENT SHORTWAVE IN SOUTHERN
CALIFORNIA IS GOING TO EJECT NORTHEASTWARD DURING THIS PERIOD...IN
RESPONSE TO YET ANOTHER SHORTWAVE IN NORTH CALIFORNIA THAT DROPS
SOUTH THROUGH THE STATE. AS THE POTENT SHORTWAVE LIFTS NORTHEAST TO
ABOUT EASTERN SOUTH DAKOTA BY 12Z TUESDAY...IT BRINGS AND DEEPENS
THE SURFACE LOW WITH IT. MODELS HAVE TRENDED WEST WITH BOTH
FEATURES...WITH THE LOW NOW REACHING NEAR MASON CITY BY 12Z TUESDAY.
A MORE WESTWARD TRACK MEANS A COUPLE OF THINGS:

1. MORE WARM AIR WILL SPREAD ALOFT OVER THE FORECAST AREA. IN
FACT...MAX TEMPERATURES ALOFT ARE NOW INDICATED BETWEEN 6-14C...
WHICH IS PLENTY WARM ENOUGH TO KEEP THE PRECIP IN A LIQUID FORM IN
THE AIR. IN ADDITION...THERE ARE NO INDICATIONS OF ICE IN THE CLOUDS
THROUGHOUT THE NIGHT...ALSO SUPPORTING LIQUID. THUS...SURFACE
TEMPERATURES WILL DETERMINE WHETHER ANY FREEZING OCCURS. THE PARTIAL
CLEARING THAT DEVELOPS THIS AFTERNOON MAY ALLOW TEMPERATURES TO
BRIEFLY DIP BELOW FREEZING THIS EVENING...BEFORE WARM ADVECTION
KICKS IN AND BRINGS TEMPS UP. IN FACT...THE WARMING IS PRETTY
IMPRESSIVE...WITH BOTH THE 28.00Z CANADIAN AND 27.12Z ECMWF BRINGING
50S INTO THE SOUTHEASTERN THIRD OF THE FORECAST AREA.
2. PRECIPITATION CHANCES. AS THE LOW LIFTS NORTHEAST...925-850MB
MOISTURE TRANSPORT AND 285-295K LIFT INCREASE SOUTHWEST TO NORTHEAST
ACROSS THE FORECAST AREA DURING THE EVENING. ALL MODELS HINT THAT
THIS WILL RESULT IN NOT ONLY CLOUDS RE-FORMING...BUT ALSO THE
DEVELOPMENT OF DRIZZLE. SINCE MUCH OF THE AREA COULD SEE A FEW
HUNDREDTHS...DRAMATICALLY INCREASED PRECIPITATION CHANCES. ALSO
INCREASED PRECIPITATION CHANCES FOR ITEM NUMBER 3 BELOW.
3. SHOWER/THUNDERSTORM POTENTIAL. THERE ARE INDICATIONS AFTER
MIDNIGHT IN THE SOUTHEASTERN HALF OF THE AREA OF SOME SHOWERS
DEVELOPING. THE 28.00Z NAM HAS UPWARDS OF 500 J/KG OF CAPE LIFTED
FROM 900MB NEAR BOSCOBEL AT 09Z. THIS CAPE WAS NOTED YESTERDAY...BUT
OFF TO THE EAST OF US GIVEN THE FARTHER EAST LOW TRACK AT THE TIME.
NOW THAT THE LOW TRACK IS FARTHER WEST...THE INSTABILITY SHIFTS A
BIT WEST. THE 28.00Z UKMET/ECMWF ALSO HINT AT THE INSTABILITY...
MORESO THAN THE 28.00Z GFS. IN ANY EVENT...ADDED A CHANCE OF
THUNDERSTORMS IN THE SOUTHEAST HALF OF THE AREA AFTER MIDNIGHT.
PROMISING SCENARIO FOR THUNDERSTORMS TOO WITH THE CAPE GETTING
INGESTED INTO THE LOW LEVEL FRONTOGENESIS CIRCULATION. CANNOT RULE
OUT SOME SMALL HAIL TOO GIVEN THE FORCING...CAPE AND FREEZING LEVELS
AROUND 8000 FT. ALSO TO NOTE IS THAT PRECIPITABLE WATER VALUES ARE
AROUND 4 STANDARD DEVIATIONS ABOVE NORMAL AT 12Z TUESDAY...OR AROUND
1 INCH.
4. FOG...THE PARTIAL CLEARING IN THE EVENING COMBINED WITH MOISTURE
COMING BACK IN IS FAVORABLE FOR FOG FORMATION. A DENSE FOG
ADVISORY WILL LIKELY BE NEEDED AGAIN. THE FOG MAY TRY TO CLEAR
OUT AS WARM AIR APPROACHES...BUT AT THE SAME TIME DEWPOINTS ARE
RISING.

TUESDAY...THE SHORTWAVE OVER EASTERN SOUTH DAKOTA AT 12Z IS PROGGED
TO LIFT UP INTO NORTHWEST ONTARIO...BRINGING THE SURFACE LOW THROUGH
EAU CLAIRE WI AND INTO EASTERN LAKE SUPERIOR AROUND 00Z WEDNESDAY.
IT APPEARS THAT THE COLD FRONT ASSOCIATED WITH THIS LOW WILL END UP
CROSSING THE FORECAST AREA WEST TO EAST THROUGH THE DAY. THIS MEANS
HIGHS COULD VARY GREATLY ACROSS THE FORECAST AREA WEST TO EAST...AND
THAT WE SHOULD SEE A FALLING TEMPERATURE CURVE...ESPECIALLY DURING
THE AFTERNOON. DRAMATICALLY INCREASED HIGH TEMPERATURES WITH THE
FARTHER WEST TRACK...TOWARDS THE 28.00Z ECMWF. THE 28.00Z REGIONAL
CANADIAN IS REALLY IMPRESSIVE...A 63F HIGH FOR THE PLATTEVILLE AREA.
DID NOT GO THAT HIGH...BUT SOMETHING TO WATCH. REGARDING
PRECIPITATION...MAY STILL BE DEALING WITH SOME LIGHT DRIZZLE IN THE
MORNING FOR MOST LOCATIONS...THEN DRY ADVECTION COMES IN BEHIND THE
COLD FRONT TO END THE PRECIPITATION FOR THE AFTERNOON. WE WILL HAVE
TO WATCH THE COLD FRONT AND FRONTOGENESIS ALONG IT. IN THE CASE OF
THE 28.00Z NAM/ECMWF...THEY STILL HAVE SOME SHOWER/THUNDERSTORM
POTENTIAL IN THE MORNING BEFORE THE FRONT PUSHES EAST. THUS...HAVE
INCLUDED SHOWER AND THUNDERSTORMS IN THE MORNING.

TUESDAY NIGHT INTO WEDNESDAY...THINGS MAY GET INTERESTING AGAIN. ALL
MODELS INDICATE THAT THE SHORTWAVE DIGGING THROUGH CALIFORNIA
THROUGH TONIGHT STRENGTHENS AS IT REACHES THE BASE OF THE TROUGH.
IN THE CASE OF THE 28.00Z GFS/UKMET...THEY BRING THIS INTENSIFYING
SHORTWAVE NORTHEAST THROUGH THE PLAINS...DEEPENING A SURFACE LOW
ALONG THE TRAILING COLD FRONT FROM TUESDAYS SYSTEM. SHOULD THIS
SCENARIO PLAY OUT...WE WOULD BE LOOKING AT A DEFORMATION BAND OF
ACCUMULATING SNOW IMPACTING THE AREA AFTER MIDNIGHT TUESDAY
MORNING THROUGH AT LEAST MID-DAY WEDNESDAY. BLOWING SNOW WOULD
ACCOMPANY IT AS WELL GIVEN INTENSIFYING WINDS. ON THE OTHER
HAND...THE 28.00Z ECMWF/CANADIAN/NAM KEEP THIS INTENSIFYING
SHORTWAVE TRACKING MORE EAST-NORTHEAST...CALL IT MORE OF A
POSITIVE TILT VERSUS A NEUTRAL TILT OF THE GFS/UKMET. THESE MODELS
ALSO HAVE THE LOW DEVELOPING ON THE FRONT...BUT BECAUSE OF THE
SHORTWAVE TRACK/TILT...THERE REALLY IS NO DEFORMATION BAND AND OUR
AREA ENDS UP DRY. SINCE THERE ARE TWO PLAUSIBLE SITUATIONS...WILL
TRY TO COMPROMISE AND HAVE 20 PERCENT CHANCES OF SNOW IN FOR BOTH
TUESDAY NIGHT AND WEDNESDAY. THIS PERIOD REMAINS HIGHLY UNCERTAIN
AND REALLY NEEDS TO BE WATCHED. BOTH SCENARIOS WOULD END UP HAVING
COLD ADVECTION AND INCREASING WINDS. IN FACT...TEMPERATURES SHOULD
JUST KEEP ON FALLING. WENT WITH A BLEND OF GUIDANCE FOR HIGHS AND
LOWS.

WEDNESDAY NIGHT...WHETHER A SYSTEM IMPACTS THE AREA ON WEDNESDAY OR
NOT...MODELS ARE IN GOOD AGREEMENT ON A DRY FORECAST AS THE AREA
LIES IN SUBSIDENCE BUT STILL GENERAL UPPER TROUGHING ALOFT. THERE
WILL BE A POTENT SHORTWAVE APPROACHING THE AREA FROM THE
NORTHWEST...DROPPING INTO MN BY 12Z. THIS SHORTWAVE IS CURRENTLY UP
IN THE YUKON TERRITORY...THUS EXPECT A SURGE OF ARCTIC AIR WITH IT.
BY 12Z THURSDAY...THE 850MB TEMPS ARE PROGGED TO FALL TO -16 TO -20C
OVER THE AREA...WITH -24C READINGS LURKING UP AROUND FARGO. THIS
CONTINUED COLD AIR ADVECTING IN WILL HELP SEND LOWS DOWN INTO THE 5
BELOW TO 5 ABOVE RANGE.

.LONG TERM...THURSDAY THROUGH SUNDAY NIGHT
344 AM CST MON JAN 28 2013

28.00Z ECMWF/GFS/CANADIAN AND ECMWF ENSEMBLES ARE IN REALLY GOOD
AGREEMENT WITH THE UPPER LEVEL AND EVEN SURFACE PATTERNS THROUGH THE
LONG TERM PERIOD.

DEEP TROUGHING IS PROGGED OVER THE EASTERN TWO THIRDS OF CANADA DOWN
INTO OUR AREA AND THE GREAT LAKES REGION FOR THURSDAY INTO
FRIDAY...AIDED BY THAT POTENT SHORTWAVE DROPPING INTO MN AT 12Z
THURSDAY. THOSE COLD 850MB TEMPS NEAR FARGO ND SLIDE INTO THE AREA
ON THURSDAY...SETTING THE STAGE FOR A CHILLY THURSDAY NIGHT. ARCTIC
HIGH PRESSURE LOOKS TO DROP INTO WESTERN IOWA BY 12Z FRIDAY...SO
THERE IS GOING TO BE A NORTHWESTERLY BREEZE THE ENTIRE TIME FROM
THURSDAY INTO THURSDAY NIGHT. THUS...EXPECT WIND CHILLS TO BE AN
ISSUE. ADVISORIES STILL LOOK LIKELY FOR THURSDAY MORNING AND
THURSDAY NIGHT. TEMPERATURES ARE GOING TO BE A LITTLE
TRICKY...DEPENDING ON IF THERE IS A SNOW PACK OR NOT. NO
PRECIPITATION IS ANTICIPATED THROUGH FRIDAY...EVEN DESPITE THE
POTENT SHORTWAVE PASSAGE...MAINLY DUE TO A LACK OF MOISTURE.

FOR THE WEEKEND...THE TROUGHING IN GENERAL SHIFTS EAST...WHICH WILL
ALLOW 500MB HEIGHTS TO RISE AND TEMPERATURES TO MODERATE. WE ARE
STILL PROGGED TO STAY IN NORTHWEST FLOW...HOWEVER. A SHORTWAVE IS
EXPECTED TO DROP THROUGH THE NORTHWEST FLOW ON SATURDAY...AND HAVE
KEPT SOME CONSENSUS 20-40 PERCENT CHANCES WITH IT. DRY WEATHER
SHOULD FOLLOW IN ITS WAKE FOR SUNDAY AS SUBSIDENCE AND HIGH PRESSURE
BUILD IN.

.AVIATION...THROUGH 18Z TUESDAY
1159 AM CST MON JAN 28 2013

DENSE FOG WILL PERSIST AT KRST THROUGH LATE AFTERNOON WITH
VISIBILITIES AROUND 1/4 MILE OR LESS AT TIMES. THE DENSE FOG IS
EXPECTED TO CONTINUE INTO THE OVERNIGHT HOURS. THERE COULD BE A
BRIEF PERIOD OF IMPROVEMENT TO IFR CONDITIONS LATE THIS AFTERNOON
BEFORE DENSE FOG REDEVELOPS THIS EVENING. PLAN ON IFR CONDITIONS
AT KLSE THROUGH THE AFTERNOON HOURS IN LOW STRATUS WITH CEILINGS
AROUND 800 FT. SHOWERS AND PERHAPS A FEW THUNDERSTORMS ARE
POSSIBLE TONIGHT AS A WARM FRONT LIFTS INTO THE REGION. FOG AND
LOW STATUS WILL CONTINUE THROUGH THE OVERNIGHT HOURS INTO EARLY
TUESDAY MORNING. SOUTH/SOUTHEAST WINDS ARE EXPECTED TO INCREASE
TONIGHT INTO THE 9 TO 13 KT RANGE.

.ARX WATCHES/WARNINGS/ADVISORIES...
1159 AM CST MON JAN 28 2013

WI...NONE.
MN...DENSE FOG ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR MNZ079-
086>088-094>096.

IA...DENSE FOG ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR IAZ008>011-
018-019-029-030.

SHORT TERM...AJ
LONG TERM....AJ
AVIATION...WETENKAMP

AREA FORECAST DISCUSSION

NWS LA CROSSE WI

540 AM CST MON JAN 28 2013

.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT
344 AM CST MON JAN 28 2013

.LONG TERM...THURSDAY THROUGH SUNDAY NIGHT
344 AM CST MON JAN 28 2013

28.00Z ECMWF/GFS/CANADIAN AND ECMWF ENSEMBLES ARE IN REALLY GOOD
AGREEMENT WITH THE UPPER LEVEL AND EVEN SURFACE PATTERNS THROUGH THE
LONG TERM PERIOD.

.AVIATION...TODAY AND TONIGHT
540 AM CST MON JAN 28 2013

WIDESPREAD IFR/LIFR CIGS/VSBYS IN BR/FG WILL REMAIN OVER THE AREA
THIS MORNING AS ABUNDANT LOW LEVEL MOISTURE REMAINS TRAPPED OVER THE
AREA BETWEEN A SFC-900MB INVERSION AND THE COLD...ICE/SLEET COVERED
GROUND. SOME INDICATIONS SUBSIDENCE IN THE WAKE OF THE DEPARTING LOW
AND WITH WEAK RIDGING BUILD IN WILL ERODE THE LOW LEVEL MOISTURE/
CLOUD DECK THIS AFTERNOON BUT INVERSION REMAINS STRONG WITH MINIMAL
CHANGE OF THE SFC-900MB AIRMASS. LEFT BKN IFR CIGS ACROSS THE AREA
THRU THE AFTERNOON BUT APPEARS FOG SHOULD LIFT WITH MVFR VSBYS FOR
THE AFTERNOON INTO THE EARLY EVENING.

ANOTHER CENTRAL PLAINS LOW HEADS TOWARD THE AREA TONIGHT...WITH
ANOTHER SURGE OF GULF OF MX MOISTURE. CIGS/VSBYS TO LOWER BACK INTO
IFR/LIFR TONIGHT AS THIS MOISTURE SPREADS NORTH OVER THE COLD GROUND.
MORE -DZ/-SHRA TO SPREAD ACROSS THE AREA TONIGHT AS THE DEEPER
MOISTURE/LIFT ARRIVES. SOME WEAK INSTABILITY SPREADS INTO THE AREA
AS WELL TONIGHT. THIS COMBINED WITH LIFT/DIVERGENCE ALOFT MAY RESULT
IN A FEW TSRA FOR KLSE AND LOCATIONS EAST/SOUTH OF KLSE. THIS VERY
LATE IN THE TAF PERIOD AND GIVEN UNCERTAINTIES DID NOT INCLUDE ANY
TSRA/CB MENTION AT THIS TIME.

BOUNDARY LAYER AIR TEMPS LOOKING TO BE ABOVE 32F TONIGHT...BUT SOME
FREEZING/ICING MAY STILL OCCUR ON RUNWAYS DUE TO THE COLD/FROZEN
GROUND.

.ARX WATCHES/WARNINGS/ADVISORIES...
344 AM CST MON JAN 28 2013

WI...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR WIZ041-053>055-061.

MN...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR MNZ079-086>088-
094>096.

IA...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR IAZ008>011-018-019-
029-030.

SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....RRS

AREA FORECAST DISCUSSION

NWS LA CROSSE WI

345 AM CST MON JAN 28 2013

.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT
344 AM CST MON JAN 28 2013

.LONG TERM...THURSDAY THROUGH SUNDAY NIGHT
344 AM CST MON JAN 28 2013

28.00Z ECMWF/GFS/CANADIAN AND ECMWF ENSEMBLES ARE IN REALLY GOOD
AGREEMENT WITH THE UPPER LEVEL AND EVEN SURFACE PATTERNS THROUGH THE
LONG TERM PERIOD.

.AVIATION...
1045 PM CST SUN JAN 27 2013

SOME PATCHY/AREAS OF FZDZ WILL CONTINUE THROUGH ABOUT 09Z...MOSTLY
AT KLSE...AS ISENTROPIC UPGLIDE CONTINUES TO WORK ON THE LOW
SATURATION. FOG COULD BECOME A GREATER CONCERN OVERNIGHT AS BUFKIT
SOUNDINGS HOLD ONTO THE ABUNDANT LOW LEVEL MOISTURE WHILE THE
PRESSURE GRADIENT SLACKENS. SFC OBS OVER MUCH OF WESTERN IA POINT TO
1/2SM OR LOWER VSBYS FROM FG. THIS FOG LOOKS MORE LIKELY FOR
KRST...AND WOULDN/T BE SURPRISED IF IT BOTTOMED OUT AT 1/4SM. WILL
STICK WITH 1/2SM FOR NOW. DENSE FOG DOESN/T LOOK AS LIKELY AT
KLSE...BUT TRENDS WILL HAVE TO BE MONITORED CLOSELY...AND UPDATES
MADE AS NEEDED.

MODELS ARE SUGGESTIVE THAT WE COULD BREAK OUT OF THE LOW CIGS INTO
SCT CONDITIONS FOR A VERY SHORT PERIOD LATE TOMORROW
AFTERNOON/EVENING /2-4 HOURS/. LOW STRATUS SHOULD QUICKLY RETURN
THOUGH...AHEAD OF ANOTHER SYSTEM MOVING OUT OF THE PLAINS. PCPN WILL
ACCOMPANY THESE CLOUDS...AND TRENDS POINT TO DZ/FZDZ. TEMPS WILL
LIKELY WARM THROUGH THE NIGHT...SO IT COULD START AS FZDZ AND SWITCH
TO DZ OVERNIGHT.

.ARX WATCHES/WARNINGS/ADVISORIES...
344 AM CST MON JAN 28 2013

WI...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR WIZ041-053>055-061.

MN...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR MNZ079-086>088-
094>096.

IA...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR IAZ008>011-018-019-
029-030.

SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RIECK

AREA FORECAST DISCUSSION

NWS CHEYENNE WY

143 PM MST MON JAN 28 2013

.SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT...
MAIN PROBLEM THIS PERIOD WILL BE SNOW OVER THE MTNS WITH SOME
POTENTIAL WIND PROBLEMS WEDS. UPPER JET STREAK IS CURRENTLY SITUATED
ACROSS NW COLORADO AND EASTERN WYOMING THIS AFTERNOON WITH A BAND
OF ENHANCED SNOWS PROGRESSING EAST ACROSS EASTERN WYOMING. LIGHT
SNOWS ALSO DEVELOPING OVER THE PANHANDLE AS UPPER DYNAMICS
IMPROVING THERE. EXPECT THIS AREA OF SNOW TO CONTINUE TO WORK EAST
ACROSS THESE AREAS INTO THIS EVENING AS THE JET ENERGY LIKEWISE
MOVES EAST THEN DIMINISH LATER TONIGHT AS UPPER DYNAMICS MOVE OUT
OF THE AREA. MAIN UPPER TROF AXIS WILL SHIFT EAST ACROSS THE
REGION TUESDAY MORNING WHICH SHOULD BRING A SHORT LULL IN THE SNOW
BEFORE ENHANCING AGAIN OVER THE HIGHER MTNS AS MOIST NW FLOW SETS
UP. CURRENT HILITES LOOK PRETTY GOOD AND WILL MAINTAIN THEM AS IS.
TEMPERATURES WILL BE ON THE COOL SIDE THROUGH WEDS. OTHER FACTOR
WILL BE WINDS ON WEDS AS LEE TROF DEEPENS OVER THE HIGH PLAINS
AND INCREASES THE PRESSURE GRADIENT ACROSS MAINLY SE WY. IN-HOUSE
WIND PROGRAM INDICATES HEALTHY SFC GRADIENT THUS SHOULD BE PRETTY
WINDY IN THE WIND PRONE AREAS. WILL HOLD OFF ON ANY HILITES FOR
NOW BUT MAY EVENTUALLY BE NEEDED.

.LONG TERM...THURSDAY THROUGH MONDAY

GOING TO STILL BE DEALING WITH A NORTHWEST TO SOUTHEAST ORIENTED
FRONT LAYING ALONG THE LARAMIE RANGE STARTING OFF THURSDAY
MORNING. PRETTY GOOD THERMAL GRADIENT FROM WEST TO EAST WITH
COLDEST AIR IN THE PANHANDLE. WEST TO NORTHWEST WINDS AT 700MB
SHOULD KEEP UPSLOPING GOING IN THE SNOWY AND SIERRA MADRE RANGES.
RAISE POPS TO LIKELY THERE FOR THURSDAY MORNING PERSISTING THROUGH
THE AFTERNOON.

GFS AND ECMWF MOVE BOUNDARY EAST INTO THE CENTRAL DAKOTAS AND
NEBRASKA BY THURSDAY EVENING AS SURFACE HIGH NORTHEAST OF THE
BOUNDARY SLIDES SOUTHEAST INTO IOWA. PRECIP SHOULD COME TO AN END
THURSDAY EVENING WITH MAYBE SOME OROGRAPHIC SNOW IN THE SNOWY AND
SIERRA MADRE RANGES.

FRIDAY COULD BE WINDY AS GFS SHOWING 700MB WINDS INCREASING TO
50KTS. THE 700MB CRAIG TO CASPER HEIGHT GRADIENT RIGHT AROUND
50MTRS. 700MB TEMPERATURES WARM...INCREASING TO AROUND -6C FRIDAY
AFTERNOON. STILL COLD IN THE PANHANDLE WITH 700MB TEMPERATURES
AROUND -8C AND 850MB TEMPERATURES AROUND +2C. WENT A FEW DEGREES
UNDER GUIDANCE FOR THE NORTHERN PANHANDLE ON FRIDAY HIGHS...WE
WILL HAVE TO WAIT AND SEE WHAT IMPACT DOWNSLOPING PLAYS ON
TEMPERATURES AS THIS TAKES PLACE. MAY HAVE GONE TOO COLD.

UPPER RIDGE BUILDS IN FOR NEXT WEEKEND WITH 700MB TEMPERATURES
CLIMBING TO -2C AS THE RIDGE BUILDS INTO THE AREA. HIGHS LOOK TO
RETURN TO THE 40S WEST OF THE LARAMIE RANGE/MID 50S EAST SATURDAY
AND POSSIBLY LOW 60S IN THE PANHANDLE FOR SUNDAY.

.AVIATION...18Z TAFS

WIDESPREAD IFR EVENT UNFOLDING AS A COLD FRONT CONTINUES TO DROP
SOUTH. NORTHEAST WINDS IN THE PANHANDLE HAVE PRODUCED WIDESPREAD
IFR/VLIFR AT ALL AIRPORTS AND SNOW CONTINUES OUT BY RAWLINS. WITH
THIS SLOW MOVING FRONT...CONDITIONS WILL NOT IMPROVE ANY DURING
THE AFTERNOON HOURS AND WILL PERSIST THROUGH THE EVENING BEFORE
NORTHWEST WINDS RETURN. CONFIDENCE HIGH ON THIS HAPPENING AS
LATEST HRRR FORECAST SHOWING SOLID IFR AND BELOW CONDITIONS TO
PERSIST ACROSS THE PANHANDLE AND EVENTUALLY INTO CHEYENNE BY LATE
THIS AFTERNOON.

.FIRE WEATHER...
NO CONCERNS EXPECTED WITH COOL TEMPERATURES AND HUMIDITIES WELL
ABOVE CRITICAL LEVELS. GUSTY WINDS EXPECTED AROUND THE MOUNTAINS
TUESDAY AND WEDNESDAY WITH QUITE GUSTY WINDS POSSIBLE IN WIND
PRONE AREAS WEDNESDAY.

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 6 PM THURSDAY FOR WYZ112-WYZ114.
WINTER WEATHER ADVISORY UNTIL 6 PM THURSDAY FOR WYZ113.
WINTER WEATHER ADVISORY UNTIL 6 AM TUESDAY FOR WYZ103.
NE...NONE.

SHORT TERM/FIRE WEATHER...RE
LONG TERM/AVIATION...CLAYCOMB

AREA FORECAST DISCUSSION

NWS CHEYENNE WY

1041 AM MST MON JAN 28 2013

.UPDATE...
MOST SIGNIFICANT CHANGE WAS TO ALTER THE TIMING AND LENGTH OF THE
WINTER WEATHER ADVISORY FOR THE NORTH LARAMIE RANGE. LATEST MODELS
SHOW MOST OF THE SNOW FALLING THERE THIS AFTERNOON AND TONIGHT
BEFORE WANING SIGNIFICANTLY LATE TONIGHT. ELSEWHERE HAVE MADE MINOR
ADJUSTMENTS TO TEMPS AND POPS GIVEN CURRENT TRENDS.

.AVIATION...18Z TAFS

CLAYCOMB

.PREV DISCUSSION... /ISSUED 414 AM MST MON JAN 28 2013/

SHORT TERM...TODAY THROUGH WEDNESDAY...
TODAY...CHALLENGES TODAY WILL BE TEMPERATURES AND AREAL COVERAGE OF
PRECIPITATION ALONG WITH PRECIPITATION TYPE.

CURRENTLY MSAS SHOWS SURFACE LOW PRESSURE DEVELOPING OVER NORTHERN
COLORADO WITH A PSEUDO WARM FRONT EXTENDING FROM THE LOW ACROSS
NORTHEAST COLORADO NEAR THE WYOMING STATE LINE. AREAS OF FOG HAVE
DEVELOPED NORTH OF A DOUGLAS TO SCOTTSBLUFF LINE.

110 KNOT 300 MB JET ORIENTED SOUTHWEST TO NORTHEAST WILL MOVE WEST
TO EAST ACROSS OUR COUNTIES ALONG WITH AN ASSOCIATED MID LEVEL
SHORTWAVE TROUGH ALOFT AND COLD FRONT. WIDESPREAD SNOW WILL OCCUR
THIS MORNING OVER CARBON COUNTY AND THE NEARBY MOUNTAINS DUE TO JET
DYNAMICS AND THE BAROCLINIC BAND PASSAGE. ALSO EXPECTING AREAS OF
FOG THIS MORNING NORTH OF A LARAMIE TO SCOTTSBLUFF LINE AS
TEMPERATURES AND DEW POINTS NARROW...THOUGH FOG WILL BE MORE LIMITED
ACROSS CARBON COUNTY WHERE SNOW OCCURS.

FOR THIS AFTERNOON...THE SURFACE LOW WILL STRENGTHEN AS IT MOVES
INTO NORTHWEST KANSAS. THE ASSOCIATED MID LEVEL SHORTWAVE TROUGH
WILL MOVE ACROSS SOUTHEAST WYOMING WITH THE THE SURFACE COLD FRONT
AND BAROCLINIC BAND SLIDING WEST TO EAST ACROSS OUR COUNTIES. BOTH
THE NAM AND GFS SHOW THE LOW AND MID LEVELS BECOMING MORE
SATURATED...THUS EXPECTING AT LEAST A SCATTERED COVERAGE OF SNOW
ACROSS ALL BUT OUR NORTHERN CONVERSE AND NIOBRARA COUNTIES. PLUS
LIFT WILL BE PRODUCED BY MID LEVEL CONVERGENCE ZONE OF WARM AIR
ADVECTION...ALONG WITH LOW LEVEL UPSLOPE AND JET INDUCED DYNAMICS.
WIDESPREAD SNOW TO DEVELOP AND SPREAD ACROSS THE SNOWY AND SIERRA
MADRE RANGES.

BASED ON EXPECTED CLOUD COVER AND EARLIER PASSAGE OF THE COLD
FRONT...WILL GO CLOSER TO COLDER GUIDANCE NAM MAXIMA.

TONIGHT...500 MB TROUGH AXIS MOVES EASTWARD ALONG THE WYOMING AND
NEBRASKA STATE LINES WITH LOW AND MID LEVEL WINDS BECOMING WEST AND
NORTHWEST...PRODUCING TEMPORARY LULL IN THE AREAL SNOW
COVERAGE...WITH 30 TO 60 PERCENT POPS ACROSS THE SIERRA MADRE AND
SNOWY RANGES AND NEARBY VALLEYS DUE TO OROGRAPHICS.

TUESDAY...FLOW ALOFT TURNS NORTHWEST WITH COLDER AIR PLUNGING
SOUTHWARD AT LOW AND MID LEVELS. MOIST FLOW ALOFT WILL COMBINE WITH
OROGRAPHICS...140 KNOT JET DYNAMICS AND SHORTWAVE TROUGHS IN THE
FLOW ALOFT TO PRODUCE WIDESPREAD SNOW ACROSS THE NORTHERN
LARAMIE...SNOWY AND SIERRA MADRE RANGES AND THE UPPER NORTH PLATTE
RIVER BASIN. UPON COORDINATION WITH OUR NEIGHBORS...AND AGREEMENT
WITH THE HPC SNOWFALL EXPECTATIONS...WE HAVE UPGRADED TO A WINTER
STORM WARNING FOR THE SNOWY AND SIERRA MADRE RANGES...WITH A WINTER
WEATHER ADVISORY FOR THE UPPER NORTH PLATTE RIVER BASIN AND SARATOGA
AND THE NORTHERN LARAMIE RANGE.

WITH COLDER TEMPERATURES...EXPECTING SNOWFALL TO LIQUID RATIOS OF 20
OR 30 TO 1...THUS MORE SNOW WILL FALL ACROSS OUR WESTERN MOUNTAINS.
SNOW SHADOWING EFFECT WILL OCCUR EAST OF A LUSK TO LARAMIE LINE WITH
WEST AND NORTHWEST WINDS. BLUSTERY DAY WITH BRISK WEST WINDS AND
AREAS OF BLOWING SNOW ACROSS OUR WESTERN MOUNTAINS.

TUESDAY NIGHT...DEEP NORTHWEST UNIDIRECTIONAL FLOW FROM THE SURFACE
TO MID LEVELS ALONG WITH PLENTY OF LOW AND MID LEVEL MOISTURE WILL
KEEP THE SNOW MACHINE AND OROGRAPHICS GOING ACROSS THE NORTHERN
LARAMIE...SNOWY AND SIERRA MADRE RANGES AND OVER THE SARATOGA VALLEY
AREA WITH DOWNSLOPING PRODUCING SNOW SHADOW EFFECTS ELSEWHERE...AND
A BRISK AND COLD NIGHT.

WEDNESDAY...FLOW ALOFT BACKS SLIGHTLY AND BECOMES MORE CYCLONIC.
PERSISTENT MOIST NORTHWEST FLOW ALONG WITH COLD TEMPERATURES IN THE
DENDRITIC GROWTH LAYER WILL AID IN 20 OR 30 TO 1 SNOWFALL RATIOS
ACROSS THE NORTHERN LARAMIE...SNOWY AND SIERRA MADRE RANGES ALONG
WITH BLOWING SNOW DUE TO PROGGED SURFACE AND LOW LEVEL GRADIENTS.
QUITE BLUSTERY AND COLD BASED ON PROGGED GRADIENTS.

LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...
THERE IS GOOD CONSENSUS WITH THE 00Z MEDIUM RANGE MODEL GUIDANCE...
PARTICULARLY WITH THE UPPER LEVEL FEATURES. A BROAD TROUGH OVER
THE CENTRAL/EASTERN CONUS WILL GRADUALLY SHIFT EAST THROUGH THE
END OF THE WEEK. THE EASTERN PACIFIC RIDGE WILL MOVE ONSHORE
FRIDAY...AND BE LOCATED EAST OF THE ROCKIES ON SUNDAY. THE NEXT
PACIFIC TROUGH WILL QUICKLY FOLLOW ON ITS HEELS SUNDAY NIGHT...
REPLACED BY RIDGING FOR MONDAY.

A SERIES OF WEAK SHORTWAVES IN THE NORTHWEST FLOW ALOFT WILL
PRODUCE PERIODS OF LIGHT TO MODERATE SNOW WEDNESDAY NIGHT AND
THURSDAY. THE OROGRAPHICALLY FAVORED SNOWY/SIERRA MADRE RANGES
WILL BENEFIT...WITH ANOTHER FOOT OF SNOW EXPECTED. THE NORTHERN
LARAMIE RANGE MAY RECEIVE UP TO A HALF FOOT OF SNOW AS WELL...WITH
AN INCH OR LESS FOR THE PLAINS. IT WILL BE SEASONABLY COOL DURING
THIS PERIOD WITH 700MB TEMPERATURES FROM -6 TO -10C. A MORE ZONAL
FLOW ALOFT AND 700MB TEMPERATURES RISING TO AROUND 0C WILL EQUATE
TO WELL ABOVE NORMAL TEMPERATURES FOR FRIDAY THROUGH MONDAY. A
WEAK SHORTWAVE TROUGH PUSHING SOUTHEAST ACROSS THE REGION MAY
BRING SOME LIGHT SNOW TO THE MOUNTAINS FRIDAY...OTHERWISE DRY
CONDITIONS WILL PREVAIL. IT WILL BE BREEZY FOR THE MAJORITY OF THE
LONG TERM...ESPECIALLY ACROSS SOUTHEAST WYOMING.

FIRE WEATHER...
NO FIRE WEATHER CONCERNS DUE TO EXPECTED HUMIDITIES.

SHORT TERM/FIRE WEATHER...RUBIN
LONG TERM...JAMSKI

AREA FORECAST DISCUSSION

NWS PUEBLO CO

1041 PM MST TUE JAN 29 2013

.AVIATION...

LIGHT SNOW SHOWERS IN THE VCNTY OF BOTH KCOS AND KPUB ARE EXPECTED
TO COME TO AN END AROUND 09Z...WITH VFR CONDITIONS THEN EXPECTED
THROUGH WEDNESDAY. WEDNESDAY AFTERNOON SOME BREEZY WEST TO
NORTHWEST WINDS WILL BE POSSIBLE AT BOTH KCOS AND KPUB. EXPECTING
KALS TO HAVE VFR CONDITIONS FOR THE NEXT 24 HOURS...WITH SOME
BREEZY WESTERLY WINDS POSSIBLE WEDNESDAY AFTERNOON.

.PREV DISCUSSION... /ISSUED 302 PM MST TUE JAN 29 2013/

SHORT TERM...
(TONIGHT AND WEDNESDAY)

SNOW HAS BEEN WINDING DOWN ACROSS THE SOUTHEAST MOUNTAINS/I-25
CORRIDOR AS FOCUS FOR HEAVIER SNOW SHIFTS EASTWARD ACROSS THE PLAINS
AHEAD OF THE MAIN UPPER TROF AXIS. SNOWFALL REPORTS THAT HAVE COME
IN SO FAR HAVE INDICATED 2 TO 5 INCHES ACROSS THE LOWER EASTERN
SLOPES OF THE SE MTS AND ADJACENT I-25 CORRIDOR. GOBBLERS KNOB WEB
CAM IN SOUTHERN PROWERS COUNTY STARTING TO PICK UP SOME HEAVIER SNOW
AS OF 2 PM...WITH GROUND NEARLY SNOW COVERED.

FOCUS FOR HEAVIER SNOW WILL CONTINUE TO SHIFT SOUTH AND EASTWARD
THROUGH THE LATE AFTERNOON AND EARLY EVENING. STILL THINKING
GENERALLY 1-3 INCHES OF SNOWFALL FOR THE SOUTHEAST PLAINS GENERALLY
TO THE SOUTH AND EAST OF KLHX. THE HEAVIEST WILL FALL ALONG THE
NORTHERN SLOPES OF THE RATON MESA AND ACROSS BACA COUNTY. WHILE 18Z
NAM CONTINUES TO DEPICT A BAND OF HEAVIER SNOW AMOUNTS OF 1 TO 3
INCHES ACROSS BACA/LAS ANIMAS...THE RAP HAS BACKED OFF ON THIS AND
NOW PLACES THE BAND WELL TO THE SOUTH OF THE AREA. HRRR ALSO
APPEARS TO HAVE BACKED OFF ON SNOW AMOUNTS ACROSS BACA COUNTY...SO
WILL HOLD OFF ON ISSUING ANY HIGHLIGHTS AT THIS POINT AND STICK WITH
THE GENERALLY 1-3 INCH AMOUNTS. WITH INSTABILITY STILL IN PLACE WITHIN THE
TROF AXIS...THERE STILL COULD BE SOME LINGERING SNOW SHOWERS BEHIND
THE TROF AXIS THROUGH THE EVENING...THUS WILL KEEP SCATTERED POPS IN
AND NEAR THE MOUNTAINS UNTIL 06Z.

MEANWHILE...ALTHOUGH HEAVIER SNOW WILL BE TAPERING
OFF...NORTHWESTERLY OROGRAPHICS AND INCREASING WINDS ALOFT ON THE
BACK SIDE OF THE UPPER TROF WILL KEEP WIDESPREAD LIGHT TO MODERATE
SNOW GOING ALONG THE SAWATCH AND MOSQUITO RANGES THROUGH THE
NIGHT...WITH THE WIND CAUSING SOME AREAS OF BLOWING SNOW. WITH
TEMPERATURES FALLING INTO THE NEGATIVE READINGS OVERNIGHT...MAY ALSO
SEE SOME WIND CHILL ADVISORY READINGS IN THE -25 TO -34 DEGREE
RANGE. PREVIOUS SHIFT ISSUED A LONG DURATION WINTER WEATHER
ADVISORY FOR THIS AREA...AND THIS STILL LOOKS GOOD...THOUGH HIGHEST
IMPACT MAY BE DUE TO MORE BLOWING SNOW INITIALLY. WILL ADD MENTION
OF THE WIND CHILL VALUES TO THE UPDATED WSW. MAY ALSO SEE WIND
CHILL ADVISORY VALUES ACROSS THE HIGHER ELEVATIONS OF THE EASTERN
SAN JUAN AND LA GARITA MOUNTAINS...THOUGH GIVEN THE SPOTTY NATURE
WILL HOLD OFF ON ISSUING A WIND CHILL ADVISORY AT THIS POINT.

TRAILING SHORTWAVE ENERGY DROPPING IN ON WEDNESDAY SHOULD ENHANCE
SNOWFALL AGAIN ACROSS THE CENTRAL MOUNTAINS WEDNESDAY AFTERNOON.
SHOULD SEE 24 HOUR ACCUMULATIONS OF 2 TO 8 INCHES THROUGH WEDNESDAY
AFTERNOON FOR THIS AREA. ELSEWHERE WX WILL BE PRIMARILY DRY. GUSTY
NORTHWEST 20-40 MPH WINDS WILL MIX DOWN INTO THE LOWER ELEVATIONS
AND ADJACENT I-25 CORRIDOR WEDNESDAY AFTERNOON WHERE GUSTS TO AROUND
20-30 MPH WILL BE POSSIBLE. SNOW COVER WOULD BODE FOR KEEPING TEMPERATURES
ON THE COOL SIDE OF GUIDANCE TOMORROW...THOUGH WITH THE WINDS AND
SOME MIXING...THEY SHOULD MANAGE TO WARM ABOVE FREEZING ACROSS MOST
OF THE PLAINS. LEANED MAX TEMPS TOWARDS THE COOLER SIDE OF GUIDANCE
FOR NOW. MOUNTAIN AREAS WILL SEE HIGHS GENERALLY IN THE TEENS
AND 20S...WITH SOME LOWER 30S ACROSS THE VALLEY AREAS. -KT

LONG TERM...
(WEDNESDAY NIGHT THROUGH TUESDAY)

WEDNESDAY NIGHT AND THURSDAY...BRISK NW FLOW ALOFT CONTINUES ACROSS
THE REGION THROUGH THURSDAY...WITH MODELS AGREEING ON KEEPING A NEARLY
CONSTANT THREAT OF LIGHT TO MODERATE PCPN OVER THE CENT MTS THROUGH
THE EVE. THOUGH NEW SNOW AMOUNTS WILL ACCUMULATE TO 12 TO 16
INCHES BY THURSDAY AFTN...ANOTHER REAL CONCERN WILL BE THE STRONG
WINDS ALOFT THAT WILL BE EXPERIENCED ACROSS THE HIGHER TERRAIN. A
100 KT CORE OF THE UPPER JET NOSES INTO THE NW QUAD OF COLORADO
THROUGH WEDNESDAY NIGHT...BEFORE MOVING EAST AND WINDS WEAKEN BY
MIDDAY THURSDAY. THEREFORE...ONGOING WINTER WX ADV FOR THE HIGHER
ELEVATIONS OF LAKE AND CHAFFEE COUNTIES LOOKS GOOD. MAX TEMPS ON
THURSDAY ARE EXPECTED TO REBOUND INTO THE 50S FOR THE PLAINS...30S
AND 40S FOR THE HIGH VALLEYS.

FRIDAY AND SATURDAY...TEMPORARY RIDGING ACROSS THE DESERT SW AND
COLORADO TO START THE WEEKEND...WITH DRY AND MILD CONDITIONS
EXPECTED. MODELS DO INDICATE A MINOR UPPER DISTURBANCE ROLLING
ACROSS THE ROCKY MT REGION...BUT CONTINUE TO KEEP THIS FEATURE JUST
NORTH OF THE CWA AND FEEL THAT THE ONLY EFFECT WILL BE AN INCREASE
IN HIGH LEVEL CLOUDINESS. WINDS REMAIN SOMEWHAT LIGHT...SO NO
APPRECIABLE CHANGE IN THE TEMPS IS EXPECTED.

SUNDAY THROUGH TUESDAY...AN UPPER LOW PRES SYSTEM JUST OFF THE S CA
COAST WILL START PUSHING A PLUME OF WARMER PACIFIC MOISTURE UP
ACROSS AZ AND THE 4 CORNERS STARTING ON SUNDAY. AT THE SAME TIME...AN
UPPER DISTURBANCE DROPPING DOWN ACROSS MT AND WY WILL ACT UPON THIS
MOISTURE TAP AND SQUEEZE OUT SOME ISOLATED SHOWERS ALONG THE CONTDVD
LATE SUNDAY. AS THIS FEATURE MOVES EAST AND OUT OF THE
AREA MONDAY...PCPN CHANCE DIMINISH. HOWEVER...LATE MONDAY THE LOW
OFF THE WEST COAST STARTS TO FILL AND MOVE ONSHORE...BRINGING A
SHOT FOR PCPN ONCE AGAIN TO THE CONTDVD STARTING TUESDAY MORNING.
27

AVIATION...
VFR CIGS ACROSS THE TAF SITES WILL GRADUALLY DIMINISH THROUGH THE
EVENING. THERE COULD BE A LIGHT SNOW SHOWER IN THE VICINITY OF KCOS
THIS EVENING...THOUGH CHANCE LOOKS TOO REMOTE TO WARRANT INCLUSION
IN THE TAF AT THIS POINT. WINDS WILL DECREASE TO UNDER 6 KTS AT KPUB
AND KALS OVERNIGHT...THOUGH KCOS MAY CONTINUE TO SEE SOME ENHANCED
NORTH WINDS IN THE 5-10 KT RANGE THROUGH THE NIGHT.
MEANWHILE...IFR TO LIFR CIGS AND VIS IN -SHSN WILL CONTINUE ALONG
THE CONTDVD...PARTICULARLY ACROSS THE CENTRAL MTS...RESULTING IN
WIDESPREAD MTN OBSCURATIONS. MVFR TO BRIEFLY IFR CIGS WILL CONTINUE
ACROSS THE SOUTHEAST PLAINS THROUGH EARLY EVENING BEFORE THE SNOW
BAND PUSHES SOUTHEAST OF THE AREA OVERNIGHT.

ON WEDNESDAY...VFR CIGS/VIS EXPECTED FOR THE TAF SITES...WITH SOME
BREEZY WEST TO NW WINDS 10-15 KTS POSSIBLE AT KCOS AND KPUB DURING
THE AFTERNOON. -KT

.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 PM MST THURSDAY FOR COZ058-060.

AREA FORECAST DISCUSSION

NWS PEACHTREE CITY GA

410 AM EST WED JAN 30 2013

.SHORT TERM /TODAY THROUGH THURSDAY NIGHT/...
PRIMARY CONCERN IS THREAT AND TIMING OF SEVERE CONVECTION THIS
AFTERNOON AND EARLY EVENING. VERY IMPRESSIVE STORM SYSTEM
APPROACHING THE STATE THIS MORNING. WHILE FAVORABLE SIG TOR
PARAMETER VALUES CURRENTLY CONFINED TO AREA CLOSER TO THE COAST
BASED ON RAP ANALYSES...HAVE SEEN A FEW REPORTS OF WIND DAMAGE
FURTHER NORTH OVER WRN TN AND NRN MS IN LOW CAPE AREAS. IF MODELS
ARE TO BE BELIEVED...PARAMETERS SHOULD BE MORE FAVORABLE HERE THAN
WHAT IS CURRENTLY SHOWN TO THE WEST. 00Z MODELS HAVE SLOWED TIMING
OF MAIN LINE OF TSRA SOMEWHAT WITH NAM SLOWEST. 06Z NAM ALSO
CONTINUING SLOWER TREND. LINE SHOULD MOVE INTO NW CORNER OF CWA
AROUND 10AM... I-85 BY 3PM AND AHN-MCN-AMERICUS LINE BY 7PM AND
EXITING SE CORNER OF CWA AROUND 10PM. INGREDIENTS STILL APPEAR
SUFFICIENT FOR AT LEAST ISOLD AREAS OF WIND DMG OR BRIEF TORNADOES.
AS OFTEN THE CASE...06Z NAM MLCAPE SHOWING MORE INSTABILITY THAN
OTHER MODELS WITH VALUES AROUND 400-700 J/KG. 00Z GFS HAS 200-400
J/KG OVER ALL BUT NE GA. VERTICAL WIND SHEAR WILL BE VERY STRONG.
0-1KM BULK SHEAR 40-50KTS SEEN ON GFS AND NAM. FAVORABLE CIN...LCL
AND DEEP LAYER SHEAR YIELDING DECENT SIG TOR PARAMETER
VALUES...1-2 WITH GFS AND 2-5 ON NAM. THIS VALUES ARE HIGHER THAN
PREV SVR EVENT ON DEC 26 WHEN WE SAW 3 WEAK TORNADOES IN MIDDLE
GA.

WINDS STILL SHOULD KEEP MOST OF AREA IN ADV CRITERIA TODAY AND THIS
EVENING. HAVE EXTENDED WIND ADV TIL MIDNIGHT. HIGH WIND WARNING
CRITERIA NOT QUITE BEING MET IN LATEST MODEL GRIDS...BUT VERY CLOSE.
WITH WET SOILS DEVELOPING QUICKLY THIS AFTERNOON...HAVE CONTINUED
WIND WARNING THRU 6PM...AFTER WHICH TIME LLJ WILL SHIFT EAST OF THE
NE GA MOUNTAINS.

HEAVY RAIN WILL ALSO BE SIGNIFICANT THREAT. AGREE WITH LATEST HPC
GUIDANCE WHICH HAS BUMPED UP EVENT TOTAL PRECIP TO 1 TO 2 INCHES
WITH SOME AREAS OF NE GA APPROACHING 2.5 INCHES...DUE TO SLOWER
TIMING AND PROGRESSION OF TSRA. SFC DEWPOINTS HAVE BEEN HIGHER THAN
FCST LAST SEVERAL HOURS AS WELL. BASED ON LATEST GRIDDED FFG AND
QPF...HAVE EXPANDED FLOOD WATCH SOUTH TO AREAS NORTH OF A FRANKLIN
TO ROSWELL TO CLEVELAND LINE.

FINALLY...ANOTHER LOW AMPLITUDE SHORT WAVE PROGGED TO MOVE ALONG
LONG WAVE TROUGH OVER TN VALLEY THURS NIGHT. WITH COLD AIR IN
PLACE...ESP ALOFT...COULD SEE SOME FLURRIES OR VERY LIGHT SNOW
SHOWERS. NO IMPACTS EXPECTED.

SNELSON

.LONG TERM /FRIDAY THROUGH TUESDAY/...
EXTENDED MODELS IN FAIRLY GOOD AGREEMENT THROUGH THE LONG
TERM...WITH LONG WAVE UPPER-LEVEL TROUGH SITUATED OVER THE EASTERN
U.S. THOUGH EARLY NEXT WEEK. GENERALLY...NORTHWEST FLOW WILL
PERSIST OVER THE REGION...AND MODELS CONTINUE TO ADVERTISE A
SERIES OF UPPER LEVEL SHORT WAVES IMPACTING THE AREA AS A RESULT.
THE FIRST DISTURBANCE OCCURS AT THE TAIL END OF THE SHORT TERM
PERIODS...AND WHAT MOISTURE QUICKLY DISSIPATES INTO THE LONG TERM
EARLY FRIDAY.

THE SECOND DISTURBANCE LOOKS TO APPROACH THE AREA LATE SATURDAY
AND REMAIN ACROSS FAR NORTH GEORGIA EARLY SUNDAY...WITH SLIGHTLY
MORE MOISTURE AVAILABLE THAN THE PREVIOUS SHORTWAVE. FOR
NOW...WITH THE LATEST MODEL TIMING FOR THIS SYSTEM...LOOKS LIKE IT
WILL PRIMARILY BE RAIN...WITH SOME POSSIBILITY OF A RAIN-SNOW MIX
INTO SUNDAY MORNING. HAVE GENERALLY GONE WITH SLIGHT CHANCE
POPS...AND HAVE KEPT NO ACCUMULATIONS FOR NORTH GEORGIA.

HAVE SCALED BACK POPS SLIGHTLY FOR THE THIRD SHORT WAVE EXPECTED
MONDAY NIGHT INTO TUESDAY. LATEST MODEL RUNS ARE LESS ENTHUSIASTIC
WITH THE FRONTAL SUPPORT...AND THEREFORE LESS AGGRESSIVE WITH
MOISTURE AND PRECIP POTENTIAL. HAVE CONTINUED WITH SLIGHT CHANCE
POPS MONDAY NIGHT AND TUESDAY...AND QUICKLY DROP POPS OFF INTO
TUESDAY NIGHT.

BELANGER

.FIRE WEATHER...
AS DRY AIR PLUNGES IN BEHIND FRONT...HUMIDITY PROGGED TO DROP TO 22
TO 25 PCT FOR A FEW HOURS THURS AFTERNOON OVER MIDDLE GA. WITH 1 TO
2 INCHES OF RAIN EXPECTED TODAY...FUELS ARE EXPECTED TO BE TOO WET
TO REQUIRE ANY FIRE DANGER STATEMENTS.

SNELSON

.AVIATION...
06Z UPDATE...
MAIN CONCERN IS TIMING OF TSRA THIS AFTERNOON. WELL DEFINED LINE
OF TSRA WILL MOVE THRU FROM WEST TO EAST...IMPACTING ATL METRO
AIRPORTS AROUND 18Z-22Z. SHOULD SEE WIDESPREAD -SHRA DEVELOPING A
FEW HOURS BEFORE THEN AND POSSIBLY CONTINUING AFTER LINE OF TSRA
HAS MOVED THRU. OTHER CONCERN TODAY IS STRONG CROSSWINDS AT
AIRPORTS WITH E-W RUNWAY CONFIGURATION...INCLUDING KATL WHERE
CROSSWIND COMPONENT GUSTS 16Z-22Z COULD APPROACH 30KTS. IFR CIGS
LIKELY AT MOST AIRPORTS FROM 09Z THRU 14Z THOUGH MAY BE TOO WARM
OVER MIDDLE GA AIRPORTS FOR CIGS TO GET DOWN TO IFR. CIGS WILL
IMPROVE AFTER LINE OF TSRA MOVES THRU...AROUND 22Z AT ATL...THEN
CLEAR ENTIRELY AFTER 06Z-09Z THURS.

//ATL CONFIDENCE...06Z UPDATE...
MEDIUM CONFIDENCE ON IFR CIGS THIS MORNING AND TSRA TIMING.
HIGH CONFIDENCE ON ALL OTHER ELEMENTS.

SNELSON

.PRELIMINARY POINT TEMPS/POPS...
ATHENS 71 38 50 33 / 100 100 5 5
ATLANTA 67 35 49 33 / 100 60 5 5
BLAIRSVILLE 61 32 43 27 / 100 60 5 20
CARTERSVILLE 67 34 47 31 / 100 40 5 10
COLUMBUS 72 38 56 39 / 100 70 5 5
GAINESVILLE 63 35 47 32 / 100 70 5 10
MACON 73 39 55 33 / 90 100 5 5
ROME 68 33 48 31 / 100 40 5 10
PEACHTREE CITY 68 36 51 32 / 100 60 5 5
VIDALIA 80 46 59 36 / 70 90 0 5

.FFC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR THE FOLLOWING
ZONES: BALDWIN...BANKS...BARROW...BARTOW...BIBB...BLECKLEY...
BUTTS...CARROLL...CATOOSA...CHATTAHOOCHEE...CHATTOOGA...
CHEROKEE...CLARKE...CLAYTON...COBB...COWETA...CRAWFORD...CRISP...
DADE...DEKALB...DODGE...DOOLY...DOUGLAS...EMANUEL...FAYETTE...
FLOYD...FORSYTH...GLASCOCK...GORDON...GREENE...GWINNETT...HALL...
HANCOCK...HARALSON...HARRIS...HEARD...HENRY...HOUSTON...
JACKSON...JASPER...JEFFERSON...JOHNSON...JONES...LAMAR...
LAURENS...MACON...MADISON...MARION...MERIWETHER...MONROE...
MONTGOMERY...MORGAN...MUSCOGEE...NEWTON...NORTH FULTON...
OCONEE...OGLETHORPE...PAULDING...PEACH...PIKE...POLK...PULASKI...
PUTNAM...ROCKDALE...SCHLEY...SOUTH FULTON...SPALDING...STEWART...
SUMTER...TALBOT...TALIAFERRO...TAYLOR...TELFAIR...TOOMBS...
TREUTLEN...TROUP...TWIGGS...UPSON...WALKER...WALTON...WARREN...
WASHINGTON...WEBSTER...WHEELER...WHITFIELD...WILCOX...WILKES...
WILKINSON.

HIGH WIND WARNING UNTIL 6 PM EST THIS EVENING FOR THE FOLLOWING
ZONES: DAWSON...FANNIN...GILMER...LUMPKIN...MURRAY...PICKENS...
TOWNS...UNION...WHITE.

FLOOD WATCH FROM 9 AM EST THIS MORNING THROUGH THIS EVENING FOR
THE FOLLOWING ZONES: BARTOW...CATOOSA...CHATTOOGA...CHEROKEE...
COBB...DADE...DAWSON...FANNIN...FLOYD...FORSYTH...GILMER...
GORDON...HARALSON...LUMPKIN...MURRAY...NORTH FULTON...PAULDING...
PICKENS...POLK...TOWNS...UNION...WALKER...WHITE...WHITFIELD.

WIND ADVISORY FROM 6 PM THIS EVENING TO MIDNIGHT EST TONIGHT FOR
THE FOLLOWING ZONES: DAWSON...FANNIN...GILMER...LUMPKIN...
MURRAY...PICKENS...TOWNS...UNION...WHITE.

SHORT TERM...SNELSON
LONG TERM....BELANGER
AVIATION...SNELSON

AREA FORECAST DISCUSSION

NWS COLUMBIA SC

403 AM EST WED JAN 30 2013

.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST TODAY AS STRONG WEATHER SYSTEM
WITH STRONG COLD FRONT MOVE TOWARD THE REGION. BOTH MOISTURE
AND WINDS WILL INCREASE WITH SHOWERS AND POSSIBLE AFTERNOON
AND EVENING THUNDERSTORMS. WARM AIR TODAY WITH HIGHS UP AROUND
80. AFTER THE COLD FRONT PASSES TONIGHT...IT WILL TURN SHARPLY
COLDER AND HIGHS THURSDAY WILL BE ALMOST 30 DEGREES COLDER.
HIGH PRESSURE FRIDAY AND SATURDAY WILL PROVIDE DRY CHILLY WEATHER
WITH BELOW NORMAL TEMPERATURES.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THROUGH MID MORNING...UPPER RIDGE TEMPORARILY HOLDING SHOWERS TO
THE WEST AND NORTH. BUT RIDGE WILL WEAKEN AND MOVE EAST FOR THE
REMAINDER OF THE NIGHT. CAE 88D JUST SHOWING SOME LIGHT SHOWERS
NORTHWEST OF HERE IN THE GSP CWA. REGIONAL RADARS SHOWING SHOWER
COVERAGE INCREASING IN GEORGIA. ACTIVITY WILL MOVE TO THE EAST
THOUGH AS INDICATED BY RUC13. RUC MODEL HAS SHOWERS ENTERING
WESTERN PART OF CAE CWA IN THE CSRA 10-12Z TIME FRAME. JUST
SHOWERS THIS MORNING BUT THUNDERSTORMS ARE POSSIBLE CLOSER TO MID
DAY` OVER THE REGION. INCREASING WIND FLOW AT SURFACE WITH
SOUTHERLY WINDS 10-20 MPH. TEMPERATURES HOLDING ABOUT 64-65
DEGREES WITH INCREASING INSTABILITY BUT LIS STILL POSITIVE AT
+3/+4/.

TODAY...DEEP TROUGH TO THE WEST WILL SHIFT EASTWARD ACROSS THE
MISSISSIPPI VALLEY AND PUSH A COLD FRONT INTO THE CAROLINAS LATE
THIS AFTERNOON. AHEAD OF THIS SYSTEM...MOISTURE FLUX WILL INCREASE
WITH GFS MODEL PWS INCREASING TO 1.60 INCHES. SIGNIFICANT 500MB
HEIGHT FALLS WILL PRECEDE THE UPPER TROUGH AS THE RIGHT ENTRANCE
REGION OF AN ASSOCIATED 150KT UPPER JET SHIFTS OVER THE SOUTHEAST
STATES. FORECAST MODELS ARE IN AGREEMENT ALSO SHOWING A VERY
STRONG...NEARLY 75KT 850MB JET SHIFTING OVER THE CAROLINAS DURING
THE AFTERNOON. TEMPERATURES ARE EXPECTED TO SURGE TO AROUND 80
IN THE AFTERNOON WITH DEWPOINTS HOLDING IN THE LOWER 60S. INSTABILITY
APPEARS TO BE LIMITED BUT WIND SHEAR WILL BE EXTREME AND THIS
LOOKS LIKE A CLASSIC HIGH SHEAR LOW CAPE (HSLC) ENVIRONMENT. DUE
TO THE STRONG WINDS AND POTENTIAL FOR STRONG WINDS TO REACH THE
SURFACE AND WILL CONTINUE THE WIND ADVISORY FROM 11AM WEDNESDAY
THROUGH 6 AM THURSDAY MORNING.

ALL OF THESE FACTORS LEAD TO REASONABLY HIGH CONFIDENCE THAT THERE
WILL BE A LINE OF CONVECTION ALONG OR JUST AHEAD OF THE FRONT THAT
WILL BE CAPABLE OF MIXING DOWN VERY STRONG WINDS TO THE SURFACE.
SPC CONTINUES TO OUTLOOK THE AREA IN A SLIGHT RISK FOR SEVERE
WEATHER WITH DAMAGING WINDS BEING THE MAIN THREAT. TIME FRAME IS
LATE AFTERNOON INTO THE EVENING HOURS. WILL CONTINUE CATEGORICAL
POPS FROM WEST TO EAST LATE AFTERNOON THROUGH EARLY EVENING.
PRECIPITATION AMOUNTS SHOULD BE LIMITED BY SPEED OF THE SYSTEM
BUT COULD SEE A QUARTER TO THREE QUARTERS OF AN INCH ACROSS THE
AREA.

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
STRONG UPPER DYNAMICS WILL CONTINUE DURING THE EVENING HOURS
UNTIL FRONTAL PASSAGE NEAR 9-10 PM TIME FRAME THIS EVENING.
THE STRONG LLJ OF AROUND 75KT WILL CONTINUE AS WELL. LOCAL
MODELS INDICATE POSSIBLY A SQUALL LINE 6-8 PM TIME FRAME AND
CONDITIONS MAY BE FAVORABLE FOR STRONG WINDS TO REACH THE
SURFACE LATE IN THE AFTERNOON OR IN THE EVENING BEFORE THE
COLD FRONT MOVES THROUGH. 20KM NAM IS GIVING LIS AROUND -2
DURING THIS TIME BUT NAM BUFR SOUNDING HAS VERY LOW CAPES
BELOW 200 J/KG AT THIS TIME AND THIS LOOKS LIKE A CLASSIC HIGH
SHEAR LOW CAPE ENVIRONMENT. SPC CONTINUES SLIGHT RISK OF SEVERE
STORMS FOR THE AREA WITH THE MAIN THREAT FROM DAMAGING WINDS.
CONTINUING WITH CATEGORICAL POPS FROM WEST TO EAST THROUGH EARLY
EVENING. AGAIN...PRECIPITATION AMOUNTS SHOULD BE LIMITED BY SPEED
OF THE SYSTEM BUT COULD SEE A QUARTER TO THREE QUARTERS OF AN
INCH ACROSS THE AREA.

BEHIND THE FRONT...COOL HIGH PRESSURE WILL BUILD INTO THE REGION
LATE WEDNESDAY NIGHT AND THURSDAY AS SKIES CLEAR FROM WEST TO EAST
AND TEMPERATURES FALL INTO THE 40S. HIGH PRESSURE WILL RESIDE OVER
THE AREA THROUGH THE END OF THE PERIOD WITH A GRADIENT IN MAX
TEMPS THU/FRI FROM LOWER 50S NORTH TO UPPER 50S SOUTH. ANOTHER
SHORTWAVE WILL CROSS THE OHIO VALLEY TO OUR NORTH ON FRIDAY AND
BRING A DRY COLD FRONT THROUGH BY FRIDAY EVENING...LEADING TO
BELOW NORMAL OVERNIGHT LOWS FRIDAY NIGHT IN THE 20S.

.LONG TERM /SATURDAY THROUGH TUESDAY/...
THE EXTENDED FORECAST WILL FEATURE AN ACTIVE WEATHER PATTERN AS
MEDIUM RANGE MODELS ARE IN REASONABLE AGREEMENT SHOWING A MEAN
NORTHWESTERLY 500MB FLOW WITH A SERIES OF SHORTWAVES MOVING OVER THE
REGION. SURFACE HIGH PRESSURE WILL BE IN PLACE SATURDAY WITH
WESTERLY UPPER FLOW...RESULTING IN MOSTLY SUNNY SKIES AND NEAR TO
SLIGHTLY ABOVE NORMAL TEMPERATURES.

THE FIRST SHORTWAVE TO CROSS THE REGION WILL TRACK SOUTHEASTWARD
ACROSS THE OHIO VALLEY INTO THE MID ATLANTIC REGION SATURDAY
NIGHT...PUSHING A COLD FRONT THROUGH THE FORECAST AREA BY SUNDAY
MORNING. MOISTURE WILL BE LIMITED WITH THIS FRONT AND LITTLE IF ANY
PRECIPITATION IS EXPECTED. MOST OF THE COLD AIR WILL REMAIN NORTH OF
THE MIDLANDS AS HIGH PRESSURE BUILDS INTO THE AREA SUNDAY AND
MONDAY. FAIR SKIES AND ABOVE NORMAL TEMPERATURES ARE EXPECTED
SUNDAY AND MONDAY WITH HIGHS IN THE UPPER 50S TO LOWER 60S AND LOWS
IN THE 30S.

A SECOND SHORTWAVE TROUGH WILL FOLLOW A SIMILAR PATH ACROSS THE OHIO
VALLEY TO THE MID ATLANTIC IN NORTHWESTERLY UPPER FLOW ON MONDAY
NIGHT INTO TUESDAY. AGAIN A COLD FRONT WILL PUSH THROUGH THE REGION
SOMETIME TUESDAY MORNING. MOISTURE WILL BE LIMITED WITH THIS FRONT
AS WELL AND PRECIPITATION CHANCES ARE EXPECTED TO BE LOW.

.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
EXPECT IFR CEILINGS WILL DEVELOP OVERNIGHT BECAUSE OF HIGH LOW-
LEVEL MOISTURE AHEAD OF THE APPROACHING WEAK WARM FRONT. THE NAM
AND GFS MOS ARE IN GOOD AGREEMENT INDICATING IFR CEILINGS. FOG
SHOULD BE LIMITED BY INCREASING BOUNDARY LAYER WIND. LOW-LEVEL
WIND SHEAR WILL OCCUR. THE MODELS INDICATE WINDS INCREASING TO
AROUND 40 KNOTS AT 2000 FEET. THE WARM FRONT SHOULD LIFT NORTH OF
THE AREA EARLY WEDNESDAY WITH STRONG HEATING AND MIXING AHEAD OF
THE APPROACHING COLD FRONT. CEILINGS SHOULD IMPROVE. WINDS WILL BE
ON THE INCREASE AHEAD OF THE APPROACHING COLD FRONT. EXPECT A LINE
OF SHOWERS WILL DEVELOP AHEAD OF THE FRONT. THERE MAY ALSO BE
THUNDERSTORMS. AN AVERAGE OF THE NAM AND GFS SUPPORTS SHOWERS
BECOMING LIKELY BEGINNING AROUND 22Z. WINDS WILL BE STRONG AND
GUSTY ESPECIALLY NEAR ANY SHOWERS OR THUNDERSTORMS. WINDS OVER 30
KNOTS MAY OCCUR.

EXTENDED AVIATION OUTLOOK...SHOWERS AND POSSIBLY THUNDERSTORMS
WILL CONTINUE INTO WEDNESDAY NIGHT. WINDS OVER 30S KNOTS MAY OCCUR
ESPECIALLY NEAR ANY SHOWERS AND THUNDERSTORMS. IT WILL BE BREEZY
BEHIND THE COLD FRONT THURSDAY. NO SIGNIFICANT IMPACTS EXPECTED
DURING THE REST OF THE OUTLOOK PERIOD.

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...WIND ADVISORY FROM 11 AM THIS MORNING TO 6 AM EST THURSDAY FOR
SCZ015-016-018-020>022-025>031-035>038-041.
GA...WIND ADVISORY FROM 11 AM THIS MORNING TO 6 AM EST THURSDAY FOR
GAZ040-063>065-077.
&&

AREA FORECAST DISCUSSION

NWS COLUMBIA SC

248 AM EST WED JAN 30 2013

.SYNOPSIS...
HIGH PRESSURE OVER THE REGION WILL MOVE EAST OVERNIGHT. A STRONG
COLD FRONT WILL APPROACH FROM THE WEST WEDNESDAY AND SWEEP THROUGH
THE AREA WEDNESDAY EVENING. WINDS WILL BE STRONG AHEAD OF THE
FRONT WEDNESDAY AFTERNOON AND SEVERE WEATHER IS POSSIBLE AS THE
FRONT PASSES. HIGH PRESSURE WILL RETURN FOR THURSDAY AND FRIDAY.

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
UPPER RIDGE TEMPORARILY HOLDING SHOWERS TO THE WEST AND NORTH.
BUT RIDGE WILL WEAKEN AND MOVE EAST FOR THE REMAINDER OF THE
NIGHT. CAE 88D JUST SHOWING SOME LIGHT SHOWERS NORTHWEST OF
HERE IN THE GSP CWA. REGIONAL RADARS SHOWING SHOWER COVERAGE
INCREASING IN GEORGIA. ACTIVITY WILL MOVE TO THE EAST THOUGH
AS INDICATED BY RUC13. RUC MODEL HAS SHOWERS ENTERING WESTERN
PART OF CAE CWA IN THE CSRA 10-12Z TIME FRAME. JUST SHOWERS
THIS MORNING BUT THUNDERSTORMS ARE POSSIBLE CLOSER TO MID DAY`
OVER THE REGION. INCREASING WIND FLOW AT SURFACE WITH SOUTHERLY
WINDS 10-20 MPH. TEMPERATURES HOLDING ABOUT 64-65 DEGREES WITH
INCREASING INSTABILITY BUT LIS STILL POSITIVE AT +3/+4/.

.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY NIGHT/...
DEEP TROUGH OVER THE INTERMOUNTAIN WEST TODAY WILL SHIFT EASTWARD
ACROSS THE MISSISSIPPI VALLEY ON WEDNESDAY WHICH WILL PUSH A
COLD FRONT INTO THE CAROLINAS LATE WEDNESDAY AFTERNOON AND CROSS
THE REGION WEDNESDAY NIGHT. AHEAD OF THIS SYSTEM...THE UPPER RIDGE
AXIS WILL SHIFT OFF THE COAST AS THE SURFACE RIDGE WEAKENS WITH
DEEP SOUTH TO SOUTHWESTERLY FLOW.

SIGNIFICANT 500MB HEIGHT FALLS WILL PRECEDE THE UPPER TROUGH AS
THE RIGHT ENTRANCE REGION OF AN ASSOCIATED 150KT UPPER JET SHIFTS
OVER THE SOUTHEASTERN STATES LATE WEDNESDAY AFTERNOON AND EVENING.
FORECAST MODELS ARE IN AGREEMENT ALSO SHOWING A VERY
STRONG...NEARLY 75KT 850MB JET SHIFTING OVER THE CAROLINAS DURING
THE AFTERNOON AND EARLY EVENING HOURS. TEMPERATURES ARE EXPECTED
TO SURGE INTO THE MID TO UPPER 70S WITH DEWPOINTS PUSHING INTO THE
LOWER TO MID 60S. PWAT VALUES ARE FORECAST TO APPROACH 1.60-1.70
INCHES JUST AHEAD OF THE FRONT...WHICH IS ABOVE THE 99TH
PERCENTILE. INSTABILITY APPEARS TO BE LIMITED BUT WIND SHEAR WILL
BE EXTREME AND THIS LOOKS LIKE A CLASSIC HIGH SHEAR LOW CAPE
(HSLC) ENVIRONMENT. DUE TO THE STRONG WINDS AND POTENTIAL FOR
STRONG WINDS TO REACH THE SURFACE...AFTER COORDINATION WITH
SURROUNDING OFFICES...WILL ISSUE A WIND ADVISORY FROM 11AM
WEDNESDAY THROUGH 6 AM THURSDAY MORNING.

ALL OF THESE FACTORS LEAD TO REASONABLY HIGH CONFIDENCE THAT THERE
WILL BE A LINE OF CONVECTION ALONG OR JUST AHEAD OF THE FRONT THAT
WILL BE CAPABLE OF MIXING DOWN VERY STRONG WINDS TO THE SURFACE.
SPC CONTINUES TO OUTLOOK THE AREA IN A SLIGHT RISK FOR SEVERE
WEATHER WITH DAMAGING WINDS BEING THE MAIN THREAT. TIME FRAME FOR
THE CONVECTION TO MOVE THROUGH THE FORECAST AREA LOOKS TO BE
BETWEEN 22Z-06Z. CONTINUING WITH CATEGORICAL POPS FROM WEST TO
EAST LATE AFTERNOON THROUGH EARLY EVENING WEDNESDAY. PRECIPITATION
AMOUNTS SHOULD BE LIMITED BY SPEED OF THE SYSTEM BUT COULD SEE A
QUARTER TO THREE QUARTERS OF AN INCH ACROSS THE AREA.

.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
EXPECT IFR CEILINGS WILL DEVELOP OVERNIGHT BECAUSE OF HIGH LOW-
LEVEL MOISTURE AHEAD OF THE APPROACHING WEAK WARM FRONT. THE NAM
AND GFS MOS ARE IN GOOD AGREEMENT INDICATING IFR CEILINGS. FOG
SHOULD BE LIMITED BY INCREASING BOUNDARY LAYER WIND. LOW-LEVEL
WIND SHEAR WILL OCCUR. THE MODELS INDICATE WINDS INCREASING TO
AROUND 40 KNOTS AT 2000 FEET. THE WARM FRONT SHOULD LIFT NORTH OF
THE AREA EARLY WEDNESDAY WITH STRONG HEATING AND MIXING AHEAD OF
THE APPROACHING COLD FRONT. CEILINGS SHOULD IMPROVE. WINDS WILL BE
ON THE INCREASE AHEAD OF THE APPROACHING COLD FRONT. EXPECT A LINE
OF SHOWERS WILL DEVELOP AHEAD OF THE FRONT. THERE MAY ALSO BE
THUNDERSTORMS. AN AVERAGE OF THE NAM AND GFS SUPPORTS SHOWERS
BECOMING LIKELY BEGINNING AROUND 22Z. WINDS WILL BE STRONG AND
GUSTY ESPECIALLY NEAR ANY SHOWERS OR THUNDERSTORMS. WINDS OVER 30
KNOTS MAY OCCUR.

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

346 AM CST WED JAN 30 2013

.MESOSCALE DISCUSSION...
240 PM CST

THE THREAT FOR HEAVY RAIN DEVELOPING AND POSSIBLY A COUPLE SEVERE
STORMS CONTINUES.

MTF

.DISCUSSION...
318 PM CST

SHORT TERM...REST OF TODAY THROUGH WEDNESDAY NIGHT...
FOR HEADLINES...KEPT FLOOD WATCH AS IS AND NO WINTER HEADLINES ARE
EXPECTED AT THIS TIME.

PWAT VALUES WILL BE IN EXCESS OF 1-1.5 INCHES THIS AFTERNOON/EVENING
WITH DEW POINTS CURRENTLY IN THE UPPER 50S TO LOW 60S FALLING
OVERNIGHT. FLOW THROUGHOUT THE ATMOSPHERIC COLUMN IS ROUGHLY
PARALLEL TO THE FRONT WHICH WILL INHIBIT THE FRONT FROM RAPIDLY
PROGRESSING THROUGH THE CWA. TRAINING WILL ALSO BECOME AN ISSUE
ALONG THE FRONT ALLOWING FOR IMPRESSIVE RAIN TOTALS. THE UPPER
LEVEL JET STRETCHES FROM TEXAS THROUGH MINNESOTA BEFORE CURVING
TOWARD QUEBEC. THE RIGHT JET ENTRANCE REGION LIES OVER SOUTHWEST
WI/NORTHWEST IL ALMOST COLLOCATED WITH THE FRONT WHICH WILL CONTINUE
TO SUPPORT THUNDERSTORM AND SHOWER FORMATION. BASED ON WHAT HAS
PASSED OVER THE OFFICE THIS AFTERNOON...SOME OF THESE SHOWERS/STORMS
WILL PRODUCE BRIEF INTENSE DOWNPOURS. THE JET AND FRONT CONTINUE
ACROSS THE CWA TONIGHT WITH THE SOUTHERN JET STREAKS LEFT EXIT
REGION POSSIBLY COUPLING WITH THE FRONT. AS SUCH EXPECTING PERIODS
OF HEAVY RAIN TO CONTINUE OVERNIGHT. WHEN ALL IS SAID AND
DONE...THINKING 1.5-2.5 INCHES OF RAIN ARE POSSIBLE ACROSS THE
AREA. LOCALLY HIGHER AMOUNTS ARE CERTAINLY POSSIBLE.

TEMPS WILL BEGIN TO FALL OVERNIGHT WITH LOWS IN THE LOW 30S NEAR RFD
TO ARND 50 NEAR RENSSELAER.

TEMPS CONTINUE TO TUMBLE TO THE TEENS OR SINGLE DIGITS WEDNESDAY
NIGHT. WINDS 20-25 MPH WITH GUSTS UP TO 30 MPH SLOWLY WEAKEN
OVERNIGHT...BUT EXPECTING WIND CHILLS TO BE BTWN 1 AND -10.

JEE

EXTENDED PERIOD...THURSDAY THROUGH TUESDAY...

RATZER

.AVIATION...

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

* CONTINUED LIGHT RAIN PERSISTING TO AROUND SUNRISE.

* LIGHT RAIN SHOWERS MIXING/SWITCHING TO LIGHT SNOW LATE MORNING
TO EARLY AFTERNOON.

* ENDING OF LIGHT SNOW FIRST PART OF THIS EVENING.

* PREVAILING IFR...OCCASIONALLY MVFR...BECOMING PREVAILING MVFR
LATE AFTERNOON.

* WINDS BECOMING NORTH AROUND SUNRISE THEN NORTHWEST BY AFTERNOON.

* WINDS INCREASE DURING THE MORNING WITH GUSTS GENERALLY 25-30KT
FROM LATE MORNING THROUGH EVENING.

TRS

//DISCUSSION...UPDATED 09Z...

MAIN AREA OF RAIN STARTING TO MOVE NORTHEASTWARD OUT OF NORTHEAST
IL AS A SHORT WAVE LIFTS RAPIDLY NORTH-NORTHEAST ACROSS EASTERN
IA. RAIN WILL CONTINUE TO BECOME LESS WIDESPREAD/MORE SHOWERY
ACROSS THE LOCAL AREA BY DAWN AS A DRY SLOT...QUITE EVIDENT IN
BOTH WATER VAPOR SATELLITE AND COMPOSITE RADAR LOOPS...PUNCHES
ACROSS NORTHERN IL THIS MORNING.

TRS

PREVIOUS DISCUSSION...UPDATED 06Z...

LARGE NE-SW BAND OF HEAVIER RAIN HAS BEEN SHIFTING EAST DURING
THE EVENING AND AS OF LATE EVENING WAS EAST HAD PROGRESSED TO THE
EAST OF ORD AND MDW. A BROAD BAND OF MAINLY LIGHT RAIN EXTENDED
WESTWARD FROM THE HEAVIER RAIN BACK TO SOUTH CENTRAL WI...WEST
CENTRAL IL AND SOUTH CENTRAL MO AS ADDITIONAL SHORT WAVES LIFT
NORTHEAST AHEAD OF THE MAIN UPPER TROUGH WITH AN AXIS ALONG A
SOUTHWEST ONTARIO TO NORTHERN TX LINE. THIS TROUGH AXIS IS
PROGGED TO REACH SOUTHWEST WI...NORTHEAST MO AND WESTERN AR BY
18Z AS IS SHOWN CONTINUING EAST AND ACROSS THE LOCAL AREA DURING
THE LATE AFTERNOON AND EARLY EVENING.

EXPECTED PRECIPITATION TO PERSIST OVERNIGHT AND ALL THE WAY INTO
EARLY EVENING. THE RAIN WILL MIX/SWITCH TO LIGHT SNOW AROUND
MIDDAY AS A SOMEWHAT ILL DEFINED SURFACE LOW CURRENTLY OVER
NORTHEAST IL/FAR SOUTHERN LAKE MI/NORTHWEST IN PROGRESSES
NORTHEASTWARD THROUGH THE GREAT LAKES AND INTO ONTARIO BY 18Z...
SPREADING COLD AIR ACROSS THE AREA AS THE TRAILING COLD FRONT
PUSHES FURTHER EASTWARD.

BETWEEN AN INCREASING PRESSURE GRADIENT SPREADING WEST TO EAST
MIDDAY THROUGH EARLY EVENING NORTH-NORTHWEST TO NORTHWEST WINDS
WILL INCREASE...AND STRENGTHENING OF THE COLD AIR ADVECTION DURING
THIS TIME SUSTAINED WINDS OF 15-20KT AND GUSTS 25-30KT ARE
EXPECTED MIDDAY AND WELL INTO TONIGHT.

CEILINGS WILL STAY BELOW 010 INTO EARLY AFTERNOON THEN RISE A BIT
TO THE 015-020 RANGE AS DEW POINT DEPRESSIONS INCREASE TO A FEW
DEGREES IN THE COLD AIR. CEILINGS ARE FORECAST TO RISE TO AT OR
ABOVE 020 IN THE EARLY TO MID EVENING AS THIS IS WHEN THE LIGHT
SNOW IS EXPECTED TO END AND LOW LEVEL DEW POINT DEPRESSIONS
INCREASE.

TRS

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

* MEDIUM CONFIDENCE IN TIMING OF SHITHC OVER FROM RAIN TO SNOW.

* MEDIUM CONFIDENCE IN WIND TRENDS.

* MEDIUM CONFIDENCE IN CEILING AND VISIBILITY TRENDS.

TRS

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

THURSDAY...CHANCE OF FLURRIES IN THE AFTERNOON/EVENING. MVFR CIGS
POSSIBLE. WEST WINDS GUSTING TO 25-30KT.

FRIDAY...VFR EARLY. CHANCE OF SNOW WITH MVFR CIGS/VIS OVERNIGHT.

SATURDAY...CHANCE OF SNOW WITH MVFR CIGS/VIS EARLY...THE VFR
OVERNIGHT.

SUNDAY...VFR. WX NIL.

MONDAY...SLIGHT CHANCE RAIN/SNOW. MVFR CIGS/VIS POSSIBLE.

KREIN

.MARINE...
345 AM CST

RAPIDLY CHANGING WINDS ARE ONGOING ACROSS THE LAKE AS A TROUGH OF
LOW PRESSURE SITUATED ACROSS THE REGION CONTINUES TO SLOWLY WORK
ITS WAY TO THE NORTHEAST TODAY. AS THIS OCCURS...THE PRESSURE
GRADIENT WILL BECOME MORE ORGANIZED WITH STRONG NORTHERLY WINDS
PICKING UP THROUGHOUT THE DAY. EXPECT NORTHERLY WINDS TO 30 KT
THIS MORNING TO CONTINUE INCREASING TO GALES TODAY AND THIS
EVENING...WITH NOW A PORTION OF THE NEARSHORE WATERS OBSERVING
THESE NORTHERLY GALES. HAVE MAINTAINED A MENTION OF GALES TO 40 KT
FOR A PERIOD LATER TODAY...AS WINDS TURN MORE TOWARDS THE
NORTHWEST AND WEST LATER TONIGHT. AS THIS OCCURS...EXPECT WINDS TO
ALSO DIMINISH TO 30 KT THURSDAY MORNING BUT WITH THESE WESTERLY
WINDS TO 30 KT CONTINUING TO AT LEAST FRIDAY MORNING. ALTHOUGH NOT
LIKELY AT THIS TIME...THERE DOES APPEAR TO BE A BRIEF WINDOW OF
SOME WEST/NORTHWEST GALES DURING THE OVERNIGHT HOURS THURSDAY
NIGHT. WILL NEED TO CONTINUE TO MONITOR THIS GALE POTENTIAL
THURSDAY NIGHT...ALSO AS STRONGER WESTERLY WINDS IN THE NEARSHORE
PERSIST AT LEAST THROUGH LATE THURSDAY NIGHT.

RODRIGUEZ

WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ008...9 AM WEDNESDAY
TO 4 PM WEDNESDAY.

IN...FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 4 AM
WEDNESDAY.

LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...9 AM WEDNESDAY TO 9 AM
THURSDAY.

SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 AM FRIDAY.

GALE WARNING...LMZ743-LMZ744-LMZ745...4 PM WEDNESDAY TO 4 AM
THURSDAY.

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

345 AM CST WED JAN 30 2013

.MESOSCALE DISCUSSION...
240 PM CST

THE THREAT FOR HEAVY RAIN DEVELOPING AND POSSIBLY A COUPLE SEVERE
STORMS CONTINUES.

MTF

.DISCUSSION...
318 PM CST

SHORT TERM...REST OF TODAY THROUGH WEDNESDAY NIGHT...
FOR HEADLINES...KEPT FLOOD WATCH AS IS AND NO WINTER HEADLINES ARE
EXPECTED AT THIS TIME.

PWAT VALUES WILL BE IN EXCESS OF 1-1.5 INCHES THIS AFTERNOON/EVENING
WITH DEW POINTS CURRENTLY IN THE UPPER 50S TO LOW 60S FALLING
OVERNIGHT. FLOW THROUGHOUT THE ATMOSPHERIC COLUMN IS ROUGHLY
PARALLEL TO THE FRONT WHICH WILL INHIBIT THE FRONT FROM RAPIDLY
PROGRESSING THROUGH THE CWA. TRAINING WILL ALSO BECOME AN ISSUE
ALONG THE FRONT ALLOWING FOR IMPRESSIVE RAIN TOTALS. THE UPPER
LEVEL JET STRETCHES FROM TEXAS THROUGH MINNESOTA BEFORE CURVING
TOWARD QUEBEC. THE RIGHT JET ENTRANCE REGION LIES OVER SOUTHWEST
WI/NORTHWEST IL ALMOST COLLOCATED WITH THE FRONT WHICH WILL CONTINUE
TO SUPPORT THUNDERSTORM AND SHOWER FORMATION. BASED ON WHAT HAS
PASSED OVER THE OFFICE THIS AFTERNOON...SOME OF THESE SHOWERS/STORMS
WILL PRODUCE BRIEF INTENSE DOWNPOURS. THE JET AND FRONT CONTINUE
ACROSS THE CWA TONIGHT WITH THE SOUTHERN JET STREAKS LEFT EXIT
REGION POSSIBLY COUPLING WITH THE FRONT. AS SUCH EXPECTING PERIODS
OF HEAVY RAIN TO CONTINUE OVERNIGHT. WHEN ALL IS SAID AND
DONE...THINKING 1.5-2.5 INCHES OF RAIN ARE POSSIBLE ACROSS THE
AREA. LOCALLY HIGHER AMOUNTS ARE CERTAINLY POSSIBLE.

TEMPS WILL BEGIN TO FALL OVERNIGHT WITH LOWS IN THE LOW 30S NEAR RFD
TO ARND 50 NEAR RENSSELAER.

TEMPS CONTINUE TO TUMBLE TO THE TEENS OR SINGLE DIGITS WEDNESDAY
NIGHT. WINDS 20-25 MPH WITH GUSTS UP TO 30 MPH SLOWLY WEAKEN
OVERNIGHT...BUT EXPECTING WIND CHILLS TO BE BTWN 1 AND -10.

JEE

EXTENDED PERIOD...THURSDAY THROUGH TUESDAY...

RATZER

.AVIATION...

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

* CONTINUED LIGHT RAIN PERSISTING TO AROUND SUNRISE.

* LIGHT RAIN SHOWERS MIXING/SWITCHING TO LIGHT SNOW LATE MORNING
TO EARLY AFTERNOON.

* ENDING OF LIGHT SNOW FIRST PART OF THIS EVENING.

* PREVAILING IFR...OCCASIONALLY MVFR...BECOMING PREVAILING MVFR
LATE AFTERNOON.

* WINDS BECOMING NORTH AROUND SUNRISE THEN NORTHWEST BY AFTERNOON.

* WINDS INCREASE DURING THE MORNING WITH GUSTS GENERALLY 25-30KT
FROM LATE MORNING THROUGH EVENING.

TRS

//DISCUSSION...UPDATED 09Z...

TRS

PREVIOUS DISCUSSION...UPDATED 06Z...

TRS

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

* MEDIUM CONFIDENCE IN TIMING OF SHITHC OVER FROM RAIN TO SNOW.

* MEDIUM CONFIDENCE IN WIND TRENDS.

* MEDIUM CONFIDENCE IN CEILING AND VISIBILITY TRENDS.

TRS

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

THURSDAY...CHANCE OF FLURRIES IN THE AFTERNOON/EVENING. MVFR CIGS
POSSIBLE. WEST WINDS GUSTING TO 25-30KT.

FRIDAY...VFR EARLY. CHANCE OF SNOW WITH MVFR CIGS/VIS OVERNIGHT.

SATURDAY...CHANCE OF SNOW WITH MVFR CIGS/VIS EARLY...THE VFR
OVERNIGHT.

SUNDAY...VFR. WX NIL.

MONDAY...SLIGHT CHANCE RAIN/SNOW. MVFR CIGS/VIS POSSIBLE.

KREIN

.MARINE...
1248 PM CST

ALLSOPP

WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ008...9 AM WEDNESDAY
TO 4 PM WEDNESDAY.

IN...FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 4 AM
WEDNESDAY.

LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...9 AM WEDNESDAY TO 9 AM
THURSDAY.

SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 AM FRIDAY.

GALE WARNING...LMZ743-LMZ744-LMZ745...4 PM WEDNESDAY TO 4 AM
THURSDAY.

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

111 AM CST WED JAN 30 2013

.MESOSCALE DISCUSSION...
240 PM CST

THE THREAT FOR HEAVY RAIN DEVELOPING AND POSSIBLY A COUPLE SEVERE
STORMS CONTINUES.

MTF

.DISCUSSION...
318 PM CST

SHORT TERM...REST OF TODAY THROUGH WEDNESDAY NIGHT...
FOR HEADLINES...KEPT FLOOD WATCH AS IS AND NO WINTER HEADLINES ARE
EXPECTED AT THIS TIME.

PWAT VALUES WILL BE IN EXCESS OF 1-1.5 INCHES THIS AFTERNOON/EVENING
WITH DEW POINTS CURRENTLY IN THE UPPER 50S TO LOW 60S FALLING
OVERNIGHT. FLOW THROUGHOUT THE ATMOSPHERIC COLUMN IS ROUGHLY
PARALLEL TO THE FRONT WHICH WILL INHIBIT THE FRONT FROM RAPIDLY
PROGRESSING THROUGH THE CWA. TRAINING WILL ALSO BECOME AN ISSUE
ALONG THE FRONT ALLOWING FOR IMPRESSIVE RAIN TOTALS. THE UPPER
LEVEL JET STRETCHES FROM TEXAS THROUGH MINNESOTA BEFORE CURVING
TOWARD QUEBEC. THE RIGHT JET ENTRANCE REGION LIES OVER SOUTHWEST
WI/NORTHWEST IL ALMOST COLLOCATED WITH THE FRONT WHICH WILL CONTINUE
TO SUPPORT THUNDERSTORM AND SHOWER FORMATION. BASED ON WHAT HAS
PASSED OVER THE OFFICE THIS AFTERNOON...SOME OF THESE SHOWERS/STORMS
WILL PRODUCE BRIEF INTENSE DOWNPOURS. THE JET AND FRONT CONTINUE
ACROSS THE CWA TONIGHT WITH THE SOUTHERN JET STREAKS LEFT EXIT
REGION POSSIBLY COUPLING WITH THE FRONT. AS SUCH EXPECTING PERIODS
OF HEAVY RAIN TO CONTINUE OVERNIGHT. WHEN ALL IS SAID AND
DONE...THINKING 1.5-2.5 INCHES OF RAIN ARE POSSIBLE ACROSS THE
AREA. LOCALLY HIGHER AMOUNTS ARE CERTAINLY POSSIBLE.

TEMPS WILL BEGIN TO FALL OVERNIGHT WITH LOWS IN THE LOW 30S NEAR RFD
TO ARND 50 NEAR RENSSELAER.

TEMPS CONTINUE TO TUMBLE TO THE TEENS OR SINGLE DIGITS WEDNESDAY
NIGHT. WINDS 20-25 MPH WITH GUSTS UP TO 30 MPH SLOWLY WEAKEN
OVERNIGHT...BUT EXPECTING WIND CHILLS TO BE BTWN 1 AND -10.

JEE

EXTENDED PERIOD...THURSDAY THROUGH TUESDAY...

RATZER

.AVIATION...

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

* CONTINUED LIGHT RAIN...OCCASIONALLY MODERATE...PERSISTING INTO
LATE MORNING...THEN MIXING/SWITCHING TO LIGHT SNOW DURING LATE
MORNING TO EARLY AFTERNOON BEFORE ENDING FIRST PART OF EVENING..

* PREVAILING IFR INTO LATE AFTERNOON...THEN MVFR THROUGH THE
EVENING.

* WINDS BECOME NORTH TO NORTHWEST AND INCREASE DURING THE
MORNING...WITH GUSTS GENERALLY 25-30KT FROM MIDDAY AND THROUGH
THE EVENING.

TRS

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

TRS

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

* HIGH CONFIDENCE IN PRECIPITATION TRENDS.

* MEDIUM CONFIDENCE IN WIND TRENDS.

* MEDIUM CONFIDENCE IN CEILING AND VISIBILITY TRENDS.

TRS

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

THURSDAY...CHANCE OF FLURRIES IN THE AFTERNOON/EVENING. MVFR CIGS
POSSIBLE. WEST WINDS GUSTING TO 25-30KT.

FRIDAY...VFR EARLY. CHANCE OF SNOW WITH MVFR CIGS/VIS OVERNIGHT.

SATURDAY...CHANCE OF SNOW WITH MVFR CIGS/VIS EARLY...THE VFR
OVERNIGHT.

SUNDAY...VFR. WX NIL.

MONDAY...SLIGHT CHANCE RAIN/SNOW. MVFR CIGS/VIS POSSIBLE.

KREIN

.MARINE...
1248 PM CST

ALLSOPP

IN...FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 4 AM
WEDNESDAY.

LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...9 AM WEDNESDAY TO 6 AM
THURSDAY.

SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...6 AM WEDNESDAY TO
10 AM THURSDAY.

GALE WARNING...LMZ743-LMZ744-LMZ745...4 PM WEDNESDAY TO 4 AM
THURSDAY.

AREA FORECAST DISCUSSION

NWS LINCOLN IL

1135 PM CST TUE JAN 29 2013

.DISCUSSION...
ISSUED 905 PM CST TUE JAN 29 2013

UPDATED ZONES/GRIDS HAVE BEEN SENT.

GEELHART

.AVIATION...
ISSUED 1127 PM CST TUE JAN 29 2013

PRIMARY FRONTAL BOUNDARY ROUGHLY ALONG A KUIN-KSQI LINE AND WILL
PUSH SLOWLY EASTWARD THE NEXT SEVERAL HOURS. A WAVE OF LOW
PRESSURE RIDING ALONG THE FRONT WILL SLOW ITS PROGRESSION THROUGH
ABOUT 15Z...THEN AFTER THAT...WINDS WILL MORE CONSISTENTLY SWING
AROUND TO THE NORTHWEST. HIGHEST WINDS EXPECTED DURING THE
AFTERNOON AND EVENING...WITH SOME GUSTS EXCEEDING 30 KNOTS.

LARGE RAIN SHIELD WILL BECOME MORE SCATTERED IN NATURE OVER THE
NEXT FEW HOURS...HOWEVER A LARGER AREA OF PRECIPITATION WILL
REDEVELOP OVER MISSOURI AND IOWA BEFORE MOVING EASTWARD. FORECAST
SOUNDINGS ARE SLOWING THE TRANSITION TO SNOW A BIT...BUT SHOULD
SWITCH AROUND 14Z NEAR KPIA AND TOWARD 17Z AROUND KDEC. CEILINGS
HAVE BEEN DROPPING BACK INTO IFR RANGE OVER WEST CENTRAL ILLINOIS
AND THIS SHOULD BECOME MORE WIDESPREAD OVER THE NEXT FEW HOURS.

GEELHART

.PREV DISCUSSION...
ISSUED 320 PM CST TUE JAN 29 2013

MAIN CONCERN THIS FORECAST PACKAGE CONTINUES TO INVOLVE THE
POTENTIAL HEAVY RAIN/FLOOD WATCH EVENT FOR TONIGHT...WHEN RAIN
WILL CHANGE OVER TO SNOW...AND FALLING TEMPS IN THE SHORT TERM.

SHORT TERM...TONIGHT THROUGH FRIDAY

LONG TERM...FRIDAY NIGHT THROUGH TUESDAY

TEMPS WILL START COLD BUT THEN WARM QUICKLY FOR THE WEEKEND AND
INTO THE BEGINNING OF NEXT WEEK. WARMEST DAY LOOKS TO BE MONDAY
WITH TEMPS 5+ DEGREES ABOVE NORMAL.

AUTEN

.ILX WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH UNTIL 6 AM CST WEDNESDAY FOR ILZ028>031-037-038-
042>046-051>057-061>063-066>068-071>073.

AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

305 AM EST TUE JAN 29 2013

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

.SYNOPSIS...
ISSUED AT 337 PM EST TUE JAN 29 2013

.NEAR TERM /REST OF TONIGHT/...

ISSUED AT 942 PM EST TUE JAN 29 2013

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...

ISSUED AT 337 PM EST TUE JAN 29 2013

ANOTHER UPPER TROUGH AND COLD FRONT PUSHES INTO THE THROUGH THE AREA
LATE THURSDAY INTO THURSDAY NIGHT...BRINGING AN ADDITIONAL CHANCE
FOR SNOW AND FALLING TEMPS.

.LONG TERM /SATURDAY THROUGH TUESDAY/...
ISSUED AT 305 AM EST WED JAN 30 2013

MODELS KEEP A BROAD UPPER TROUGH ACROSS EASTERN CANADA...GREAT LAKES
AND NORTHEAST U.S. THROUGH THE PERIOD. THERE ARE A COUPLE OF WEAK
UPPER DISTURBANCES THAT WILL ROTATE ACROSS OUR AREA WITH ONE
OCCURRING AROUND SATURDAY...ANOTHER ONE LATE MONDAY AND THE EURO HAS
ONE OCCURRING LATE TUESDAY...WHICH THE GFS DOES NOT.

CONFIDENCE OF TUESDAY SYSTEM IS VERY LOW...HOWEVER ALL MODELS HAVE
TRENDED WITH HIGHER POPS THEN...SO WILL ADD SLIGHT CHANCE OF SNOW
SHOWERS DAY 7. OTHERWISE ALL BLEND POPS SEEM REASONABLE IN MOST
OTHER CASES.

AS FAR AS TEMPERATURES ARE CONCERNED MODELS HAVE TRENDED A LITTLE
COLDER OVER THE WEEKEND AND TUESDAY. IN MOST CASES WENT WITH A
BLEND OF ALL BLEND AND CONSALL NUMBERS.

.AVIATION /DISCUSSION FOR THE 30/06Z TAF ISSUANCE/...

ISSUED AT 1055 PM EST TUE JAN 29 2013

SEVERE SQUALL LINE ACROSS EASTERN ILLINOIS AND SOUTHEASTERN MISSOURI
LATE THIS EVENING WILL BE NEAR IND AND BMG AROUND ISSUANCE
TIME...AND WITH TORNADO WATCH IN EFFECT FOR BMG...WILL GO WITH A
TEMPO 40 KNOT SUSTAINED AND 50 KNOT GUST THROUGH 09Z WITH OTHERWISE
SOUTHWWEST WINDS AROUND 20 KNOTS WITH GUSTS TO 35 KNOTS THE
REMAINDER OF THE NIGHT. WINDS WILL SHIFT TO SOUTHWEST AND WEST AND
THE SOLID RAINS SHOULD END BEHIND THE COLD FRONT THAT SHOULD MOVE
THROUGH AROUND 12Z AT HUF AND HUF AND 14Z AT IND AND BMG. WINDS
WHOULD STAY UP THROUGH THE ENTIRE TAF PERIOD BUT SLIGHTLY DECREASE
IN SPEED AT IND AFTER 06Z THURSDAY. BASED ON LIGHTNING DATA...WILL
GO WITH TEMPO THUNDERSTORMS AT IND AND BMG THROUGH 09Z AND THE OTHER
SITES ONLY UNTIL 07Z. COULD SEE SOME MORE SHOWERS THIS AFTERNOON
POSSIBLY MIXED WITH SNOW LATE...BUT COVERAGE APPEARS TOO LOW TO
MENTION IN TAFS AT LEAST AT THIS TIME. MVFR CONDITIONS...EXCEPT IFR
IN THUNDERSTORMS TO BECOME VFR AFTER 15Z PER MODEL TIME SECTIONS.

.IND WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH THROUGH WEDNESDAY MORNING FOR INZ021-028>031-035>049-
051>057-060>065-067>072.

SYNOPSIS...MRD
NEAR TERM...MRD/TDUD
SHORT TERM...MRD
LONG TERM....JH
AVIATION...MK

AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

1055 PM EST TUE JAN 29 2013

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

.SYNOPSIS...
ISSUED AT 337 PM EST TUE JAN 29 2013

.NEAR TERM /REST OF TONIGHT/...

ISSUED AT 942 PM EST TUE JAN 29 2013

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...

ISSUED AT 337 PM EST TUE JAN 29 2013

ANOTHER UPPER TROUGH AND COLD FRONT PUSHES INTO THE THROUGH THE AREA
LATE THURSDAY INTO THURSDAY NIGHT...BRINGING AN ADDITIONAL CHANCE
FOR SNOW AND FALLING TEMPS.

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

ISSUED AT 144 PM EST TUE JAN 29 2013

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

.AVIATION /DISCUSSION FOR THE 30/06Z TAF ISSUANCE/...

ISSUED AT 1055 PM EST TUE JAN 29 2013

.IND WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH THROUGH WEDNESDAY MORNING FOR INZ021-028>031-035>049-
051>057-060>065-067>072.

SYNOPSIS...MRD
NEAR TERM...MRD/TDUD
SHORT TERM...MRD
LONG TERM....SMF
AVIATION...MK

AREA FORECAST DISCUSSION

NWS DES MOINES IA

1147 PM CST TUE JAN 29 2013

.UPDATE...
ADDED 06Z TAF DISCUSSION.

THERE WILL BE LITTLE CHANGE IN THINKING WITH A TOKEN EVENING UPDATE
TO FIT CURRENT OBS. WAS ORIGINALLY THINKING THAT FORECAST AMOUNTS
MAY BE TOO HIGH ON NW FRINGE OF FORECAST PRECIP SHIELD...HOWEVER 00Z
NAM IS NOW PLACING HEAVIEST SNOWFALL AXIS SW-NE RIGHT THROUGH DES
MOINES. FAR NW FRINGE OF ADVISORY MAY BE OVERDONE...BUT STILL LOOKS
LIKE FORT DODGE AND MASON CITY AREAS MAY BE BRUSHED...ESPECIALLY SRN
PORTIONS OF THOSE COUNTIES. NO CHANGES IN HEADLINES WHICH
CONFIDENCE IN ANY PARTICULAR SOLUTION NOT GREAT ENOUGH TO CHANGE
THINGS. LOOKED TO THE RAP FOR GUIDANCE BUT PAST SEVERAL RUNS ARE
LITTLE HELP AS THEY HAVE BEEN CONSISTENTLY TOO AGGRESSIVE IN TIMING
AND STRENGTH WITH PRECIP ONSET INTO IA.

.AVIATION...30/06Z
CONFIDENCE IN NEAR BLIZZARD CONDITIONS IS WANING SOMEWHAT. DEEP
VERY STRONG FORCING UPSTREAM IS NOT RESULTING IN SNOW VISIBILITY AS
LOW AS EXPECTED. THUS STILL HAVE IFR/LIFR CONDITIONS IN THE
FORECAST...BUT MORE INFLUENCED BY CIGS RATHER THAN LIFR VSBYS.
STILL EXPECT WIND GUSTS 25-30KTS HOWEVER. ALTHOUGH LOWER VSBYS IN
SNOW SHOULD END BY MIDDAY...AT LEAST MVFR CIGS AND SOME FLURRIES
SHOULD LINGER THROUGH THE AFTERNOON WITH WINDS DIMINISHING BY THAT
TIME AS WELL.

WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON CST WED
AUDUBON-CARROLL-CASS-CERRO GORDO-FRANKLIN-GREENE-GUTHRIE-HAMILTON-
WEBSTER-WRIGHT

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

AREA FORECAST DISCUSSION

NWS TOPEKA KS

1134 PM CST TUE JAN 29 2013

.DISCUSSION...
SEE PREV DISCUSSION.

.AVIATION...
DEFORMATION BAND OF SNOW HAS FORMED TO THE WEST OF THE
TERMINALS...AND THE RAP AND NAM CONTINUE TO SHOW THIS BAND MOVING
ACROSS NORTHEAST KANSAS OVERNIGHT. TIMING IS SEVERAL HOURS SLOWER
FROM THE PREV FORECAST WITH SNOW LIKELY PERSISTING AT TOP AND FOE
UNTIL 14Z. MODELS ALSO SUGGEST A LACK OF ICE IN THE TOP OF THE CLOUD
INITIALLY. WITH SEVERAL REPORTS OF PL UPSTREAM...HAVE INTRODUCED A
MIX OF -SNPL UNTIL THE BETTER DEFORMATION BAND MOVES IN AND
SATURATES THE DENDRITIC GROWTH ZONE FOR A PERIOD OF MODERATE SNOW.
CONFIDENCE IS HIGH THAT THERE WILL BE IFR AND LIFR CONDITIONS DURING
THE NEXT 8 TO 12 HOURS.

WOLTERS

.PREV DISCUSSION... /957 PM CST TUE JAN 29 2013/
A BAND OF SNOW HAS DEVELOPED ACROSS SOUTHWESTERN AND CENTRAL KANSAS
WITHIN THE DEFORMATION ZONE OF THE UPPER TROUGH. THE LATEST RAP AND
NAM PROGS SUGGEST THIS BAND OF SNOW WILL CONTINUE TO MOVE EAST AND
NORTHEAST ACROSS THE NORTHERN TWO THIRDS OF THE FORECAST AREA...WITH
THE HEAVIEST BAND SETTING UP NORTH OF AN ABILENE TO HOLTON LINE.
MODELS HAVE ALSO TRENDED SOUTH WITH THE SNOW ACCUMULATIONS AND SHOW
A COUPLE INCHES POSSIBLE ALONG INTERSTATE 70. WITH MODELS STILL
SHOWING DECENT FRONTOGENETICAL FORCING AND THE DEFORMATION BAND
HAVING ALREADY FORMED...HAVE EXPANDED THE ADVISORY A LITTLE FURTHER
SOUTH TO INCLUDE DICKINSON...GEARY...MORRIS AND WABAUNSEE COUNTIES.

WOLTERS

/556 PM CST TUE JAN 29 2013/
21Z RAP AND 18Z NAM HAVE STARTED TO SHOW SOME INDICATION OF A DECENT
FRONTOGENETICAL BAND DEVELOPING MAINLY DURING THE 06Z TO 12Z TIME
FRAME. WITH RECENT RADAR TRENDS SHOWING A BAND STARTING TO FORM
ACROSS WESTERN KS...AM BEGINNING TO THINK THAT MODELS ARE DOING A
REASONABLE JOB DEPICTING THE SYSTEM AS IT LIFTS OUT OVERNIGHT.
CONFIDENCE IS INCREASING THAT THERE WILL BE SNOW. SNOW AMOUNTS SEEM
TO BE IN THE BALLPARK INITIALLY. WITH SOME UNCERTAINTY FROM THE PREV
FORECAST ABOUT MESOSCALE FORCING...THINK THAT FORECAST SNOW AMOUNTS
ARE PROBABLY NOT ON THE LOW SIDE. THERE ARE STILL SOME QUESTIONS
WITH SOME INDICATIONS OF MID LEVEL DRY AIR COMING IN AT THE
DENDRITIC GROWTH ZONE AND A GENERAL LACK OF INSTABILITY OF
CONDITIONAL INSTABILITY THAT COULD ACT TO KEEP SNOW AMOUNT ON WITHIN
THE FORECASTED VALUES. IF ANYTHING WILL NEED TO WATCH THINGS
PROGRESS AND POTENTIALLY EXPAND THE ADVISORY IF INDEED A BAND OF
MODERATE SNOW MOVES ACROSS THE AREA. MODELS CONTINUE TO SHOW A
STRENGTHENING PRESSURE GRADIENT WITH NORTH AND NORTHWEST WINDS
GUSTING UP TO 35 MPH.

WOLTERS

/328 PM CST TUE JAN 29 2013/
THE ABRUPT RETURN TO WINTER CONTINUES TODAY ACROSS THE FORECAST
AREA...AFTER A ROUND OF MORNING SHOWERS AND THUNDERSTORMS FOR
EASTERN PORTIONS OF THE STATE. THE DEEP LONGWAVE TROF CONTINUES TO
MOVE EASTWARD ACROSS THE ROCKY MOUNTAINS AND INTO THE HIGH PLAINS.
ENERGY ROTATING THROUGH THE TX PANHANDLES AIDING IN ENHANCING A
NEGATIVE TILT TO THE SOUTHERN STREAM AS IT LIFTS INTO OUR AREA
THIS EVENING AND OVERNIGHT.

.TOP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY TIL 7AM WED FOR KSZ008-009-020>022-034>037.

WINTER WEATHER ADVISORY TIL 9AM WED KSZ010>012-023-024-026-038>040.

AREA FORECAST DISCUSSION

NWS TOPEKA KS

957 PM CST TUE JAN 29 2013

.DISCUSSION...
A BAND OF SNOW HAS DEVELOPED ACROSS SOUTHWESTERN AND CENTRAL KANSAS
WITHIN THE DEFORMATION ZONE OF THE UPPER TROUGH. THE LATEST RAP AND
NAM PROGS SUGGEST THIS BAND OF SNOW WILL CONTINUE TO MOVE EAST AND
NORTHEAST ACROSS THE NORTHERN TWO THIRDS OF THE FORECAST AREA...WITH
THE HEAVIEST BAND SETTING UP NORTH OF AN ABILENE TO HOLTON LINE.
MODELS HAVE ALSO TRENDED SOUTH WITH THE SNOW ACCUMULATIONS AND SHOW
A COUPLE INCHES POSSIBLE ALONG INTERSTATE 70. WITH MODELS STILL
SHOWING DECENT FRONTOGENETICAL FORCING AND THE DEFORMATION BAND
HAVING ALREADY FORMED...HAVE EXPANDED THE ADVISORY A LITTLE FURTHER
SOUTH TO INCLUDE DICKINSON...GEARY...MORRIS AND WABAUNSEE COUNTIES.

WOLTERS

.PREV DISCUSSION... /556 PM CST TUE JAN 29 2013/
21Z RAP AND 18Z NAM HAVE STARTED TO SHOW SOME INDICATION OF A DECENT
FRONTOGENETICAL BAND DEVELOPING MAINLY DURING THE 06Z TO 12Z TIME
FRAME. WITH RECENT RADAR TRENDS SHOWING A BAND STARTING TO FORM
ACROSS WESTERN KS...AM BEGINNING TO THINK THAT MODELS ARE DOING A
REASONABLE JOB DEPICTING THE SYSTEM AS IT LIFTS OUT OVERNIGHT.
CONFIDENCE IS INCREASING THAT THERE WILL BE SNOW. SNOW AMOUNTS SEEM
TO BE IN THE BALLPARK INITIALLY. WITH SOME UNCERTAINTY FROM THE PREV
FORECAST ABOUT MESOSCALE FORCING...THINK THAT FORECAST SNOW AMOUNTS
ARE PROBABLY NOT ON THE LOW SIDE. THERE ARE STILL SOME QUESTIONS
WITH SOME INDICATIONS OF MID LEVEL DRY AIR COMING IN AT THE
DENDRITIC GROWTH ZONE AND A GENERAL LACK OF INSTABILITY OF
CONDITIONAL INSTABILITY THAT COULD ACT TO KEEP SNOW AMOUNT ON WITHIN
THE FORECASTED VALUES. IF ANYTHING WILL NEED TO WATCH THINGS
PROGRESS AND POTENTIALLY EXPAND THE ADVISORY IF INDEED A BAND OF
MODERATE SNOW MOVES ACROSS THE AREA. MODELS CONTINUE TO SHOW A
STRENGTHENING PRESSURE GRADIENT WITH NORTH AND NORTHWEST WINDS
GUSTING UP TO 35 MPH.

WOLTERS

.TOP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY TIL 7AM WED FOR KSZ008-009-020>022-034>037.

WINTER WEATHER ADVISORY TIL 9AM WED KSZ010>012-023-024-026-038>040.

AREA FORECAST DISCUSSION

NWS LOUISVILLE KY

1158 PM EST TUE JAN 29 2013

...Updated Aviation Discussion...

.Mesoscale Forecast Update...
1115 PM EST Tue Jan 30 2013

Updated the zones and other public products to include tornado watch
number 12 which is in effect until 5 AM EST Wednesday.

Forecast continues to be on target for the overnight period. Severe
QLCS is in progress to the west of our area and is approaching the
Wabash and Ohio Rivers in far western Kentucky. Upstream reports
from WFO Paducah reveal quite a bit of wind damage with this linear
system. Mesoscale analysis continues to show more than 70kts of
effective shear which should increase a bit more over the next few
hours. VAD wind profiles from PAH still show nearly 100kts of wind
at 4000 ft AGL and calculating SRH from the VAD profiles show 0-1KM
SRH of 550-650 M2/S2 and 0-3KM SRH of over 1000 M2/S2. Thus, with
the shear and the strong theta-e advection mixing out the low-level
inversion, this line should become more surface rooted and increase
in intensity as it heads east. Damaging winds are very likely with
this line overnight and embedded tornadoes within QLCS mesovortices
and bowing line segments are likely.

Based on current progression, this activity should be on our border
with WFO PAH around 1230-130 AM EST and in the I-65 corridor
including Louisville around 2-3 AM and then toward the I-75 between
3-5 AM EST. This is a little faster than previously indicated due
to the fact that the line is speeding up a bit due to cold pool
generation behind the line.

Previously issued at 830 PM EST Tue Jan 30 2013

Aside from the strong winds associated with the convection, gradient
winds continue to strengthen. Some gusts are currently around 30
knots, with stronger winds likely as this system approaches.

.Short Term (Tonight through Wednesday Night)...
Issued at 320 PM EST Tue Jan 29 2013

...Strong to Severe Storms Expected Early Wednesday Morning With
Wind Damage and Isolated Tornadoes Being The Main Threats...

.Long Term (Thursday through Tuesday)...
Issued at 325 PM EST Tue Jan 29 2013

.Aviation (06Z TAF Issuance)...
Issued at 1158 PM EST Tue Jan 29 2013

Deep upper trough over the Plains will drive a surface low pressure
system from the Plains and into the Great Lakes during the day on
Wednesday. Strong surface cold front is located to our west with a
pre-frontal trough axis out ahead of the cold front. Quasi-linear
convective system is well developed and located along the IN/IL/KY
border area and heading east at around 50kts.

Based on the latest radar data, this line will impact the KBWG
terminal around 0630-0830Z. It should be reaching the KSDF terminal
around 0700-0800Z and the KLEX terminal around 0900-1000Z. Have
continued to advertise a period of VCTS just before the above
mentioned times to account for any development that may occur ahead
of the line. Will be keeping a very close met watch on the TAF`s
tonight and will be updating to time the lines into the terminals as
they approach. Feel that conditions will be quite poor when the
squalls go through. Variable winds of 25G35kt will be possible for
a time. LLWS will continue to be a problem until the main
convective line passes.

MVFR cigs will continue behind the line with conditions not
improving until mid-late morning. Previous thinking of a second
low-topped line of convection developing still looks like a
possibility and we`ll address those issues in later forecasts.

.Hydrology...
Issued at 300 AM EST Tue Jan 29 2013

.LMK WATCHES/WARNINGS/ADVISORIES...
IN...WIND ADVISORY UNTIL 4 PM EST /3 PM CST/ WEDNESDAY FOR
INZ076>079-
083-084-089>092.

KY...WIND ADVISORY UNTIL 4 PM EST /3 PM CST/ WEDNESDAY FOR
KYZ023>032-
061-062-070>072.

WIND ADVISORY UNTIL 7 PM EST /6 PM CST/ WEDNESDAY FOR
KYZ033>043-
045>049-053>057-063>067-073>078-081-082.

Mesoscale........MJ/MJP
Short Term.......RJS
Long Term........lg
Aviation.........MJ
Hydrology........CMC

AREA FORECAST DISCUSSION

NWS LOUISVILLE KY

1118 PM EST TUE JAN 29 2013

.Mesoscale Forecast Update...
1115 PM EST Tue Jan 30 2013

Updated the zones and other public products to include tornado watch
number 12 which is in effect until 5 AM EST Wednesday.

Previously issued at 830 PM EST Tue Jan 30 2013

Aside from the strong winds associated with the convection, gradient
winds continue to strengthen. Some gusts are currently around 30
knots, with stronger winds likely as this system approaches.

.Short Term (Tonight through Wednesday Night)...
Issued at 320 PM EST Tue Jan 29 2013

...Strong to Severe Storms Expected Early Wednesday Morning With
Wind Damage and Isolated Tornadoes Being The Main Threats...

.Long Term (Thursday through Tuesday)...
Issued at 325 PM EST Tue Jan 29 2013

.Aviation (00Z TAF Issuance)...
Issued at 642 PM EST Tue Jan 29 2013

.Hydrology...
Issued at 300 AM EST Tue Jan 29 2013

.LMK WATCHES/WARNINGS/ADVISORIES...
IN...WIND ADVISORY UNTIL 4 PM EST /3 PM CST/ WEDNESDAY FOR
INZ076>079-
083-084-089>092.

KY...WIND ADVISORY UNTIL 4 PM EST /3 PM CST/ WEDNESDAY FOR
KYZ023>032-
061-062-070>072.

WIND ADVISORY UNTIL 7 PM EST /6 PM CST/ WEDNESDAY FOR
KYZ033>043-
045>049-053>057-063>067-073>078-081-082.

Mesoscale........MJ/MJP
Short Term.......RJS
Long Term........lg
Aviation.........RJP
Hydrology........CMC

AREA FORECAST DISCUSSION

NWS BALTIMORE MD/WASHINGTON DC

454 AM EST WED JAN 30 2013

.SYNOPSIS...
LOW PRESSURE IS CENTERED OVER MICHIGAN. FROM THIS A WARM EXTENDS
ACROSS PENNSYLVANIA WHILE A COLD FRONT EXTENDS FROM INDIANA TO
ARKANSAS. THE COLD FRONT WILL MOVE THROUGH THE MID ATLANTIC STATES
THIS EVENING. ANOTHER COLD FRONT WILL MOVE THROUGH THE REGION
FRIDAY...FOLLOWED BY HIGH PRESSURE SATURDAY.

.NEAR TERM /TODAY/...
AS OF 08Z...COLD FRONT IS OVER THE UPR MIDWEST WITH A PREFRONTAL
BAND OF THUNDERSTORMS ASSOCIATED WITH A STRONG GULF PLUME EXTENDS
FROM THE MS DELTA TO DETROIT. A WIDE SWATH OF TRAILING STRATIFORM
IS OVER WRN IL AND IN.

THIS COLD FRONT AND PREFRONTAL ACTIVITY WILL PROGRESS EAST THROUGH
TODAY. THE 05Z HRRR DOES PLACE THE PREFRONTAL BAND AT THE ALLEGHENY
FRONT BY 18Z...LESS THAN 10 HRS. THAT IS QUITE FAST...WITH 20Z
SEEMINGLY A BETTER GUESS AS OF NOW. FLASH FLOOD WATCH IS IN EFFECT
FOR COUNTIES ALONG THE ALLEGHENY FRONT AS WELL AS HAMPSHIRE/HARDY
WHERE 6 HR FLASH FLOOD GUIDANCE IS AROUND AN INCH /1-2 INCHES ARE
EXPECTED FOR THOSE COUNTIES/. ANY OTHER FLOODING LOOKS TO BE IN
URBAN AREAS LIKE BALT-WASH. OTHERWISE A WELCOME HEAVY RAINFALL.

SEVERE THREAT. VERY STRONG SHEAR AND VERY LOW CAPE WILL RESULT IN A
DYNAMIC BAND. GUSTS AROUND 50 KT POSSIBLE WITH THIS BAND ACROSS THE
LWX CWA. KEPT THUNDER CHANCES AT JUST CHANCE THOUGH THE MIDWEST HAS
HAD A FAIR SHARE OF THUNDER TONIGHT.

WIND. A STRONG LLJ AHEAD OF THIS FRONT WILL INCREASE OVERHEAD
THROUGH THE DAY. A WIND ADVISORY IS IN EFFECT FOR MAJOR RIDGELINES
BLUE RIDGE AND WEST FROM NOON THROUGH TONIGHT. WIND SHIFT TO WEST
WITH FRONT WILL OCCUR SHORTLY AFTER MIDNIGHT. AS OF NOW WLY FLOW
LOOKS TO BE BELOW 40 KT GUSTS...SO LATER SHIFTS WILL HAVE TO HONE IN
ON IF THERE IS A WIND THREAT FOR LATE TONIGHT/THURSDAY MORNING.

TEMPERATURES. WARM AHEAD OF THE COLD FRONT WITH UPR 50S OUT THERE
NOW EASILY REACHING THE UPR 60S/LOW 70S BEFORE PREFRONTAL
PRECIP/CLOUDS LIMIT INCREASES. 850MB TEMPS ARE NEAR 12C...SO MID 70S
WOULD BE POSSIBLE IN SUNNY CONDITIONS.

.SHORT TERM /TONIGHT/...

PRECIP SLOWLY CUTS OF WITH STRATIFORM TRAILING MAIN BAND
FOR A FEW HOURS. UPSLOPE SNOW OF ONLY A COUPLE INCHES. NO WINTER
ADVISORY EXPECTED.

.LONG TERM /THURSDAY THROUGH TUESDAY/...
AFTR TUE AND TDA`S VERY WARM TEMPS THE RGN WL RETURN TO MORE
NORMAL LATE JAN/ERLY FEB TEMPS FOR THE XTND PD.

BRZY/WINDY WL BE THE OPERATIVE WORDS FOR THU AS HIGH PRES BUILDS
INTO THE RGN. TEMPS THU WL BE 25 DEGS COOLER THAN TDA. UPSLOPE
SNSH WL ALSO BE A CONCERN W/ SVRL INCHES OF ACCUM PSBL IN THE
HIGHLANDS. AM ADVSRY MAY BE REQUIRED.

HIGH PRES WL BUILD INTO THE RGN FRI AFTN AND SAT. HIGHS GNRLY IN
THE U30S E OF THE MTNS. LOWS IN THE 20S.

UPPER-LEVEL DISTURBANCES WILL BRING A CHANCE FOR SNOW SHOWERS...W/
THE BEST CHCS BEING ACROSS THE NORTHERN AND WESTERN CWA. DURG THE
XTND PD FAST UPR LVL WL PREVAIL..AND W/ THIS IS THE PTNL FOR MORE
ALBERTA CLIPPERS. A DISTURBANCE WILL PASS THROUGH SATURDAY NIGHT.
ANOTHER MAY IMPACT THE AREA TUE.

HIGHS CONT IN THE U30S/L40S SUN THRU TUE. LOWS IN THE MU20S.

.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
IFR STILL POSSIBLE THROUGH MID MORNING. SLY LOW LEVEL WIND SHEAR
INCREASES TODAY PEAKING TONIGHT JUST AHEAD OF A COLD FRONT. CHANCES
FOR THUNDER WITH VERY GUSTY WINDS...ON THE ORDER OF 50 KT. WINDS
SHIFT WEST AND DECREASE LATE TONIGHT.

GUSTY NW WINDS XPCTD THU. SKIES/CIGS SHOULD BE VFR. VFR CONDITIONS
ARE EXPECTED MOST OF THE TIME THU NIGHT THROUGH SUNDAY.

.MARINE...
SLY GALE EXPECTED BY LATE AFTERNOON CONTINUING UNTIL THE COLD FRONT
CROSSES LATE TONIGHT.

HIGH PRES BLDG INTO THE WATERS WL LKLY CONT TO CAUSE STRONG WIND
GUSTS DURG THU. HV ISSUED A GALE WRNG FOR CHES BAY/LWR TIDAL
PTMC...AND A STRONG SCA FOR THE RMDR OF THE WATERS.

A COLD FRONT WILL PASS THROUGH THURSDAY NIGHT, GUSTY WINDS ARE
EXPECTED BEHIND THE FRONT FRIDAY. HIGH PRES OVR THE WATERS SAT.
ANOTHER COLD FRONT MAY IMPACT THE WATERS SUNDAY.

.TIDES/COASTAL FLOODING...
A SOUTHERLY FLOW WILL INCREASE TODAY WITH GUSTS AROUND 35 KNOTS
DURING THE AFTERNOON AND EVENING HOURS. THE STRONG SOUTHERLY FLOW
WILL PUSH WATER UP THE MARYLAND PORTION OF THE CHESAPEAKE BAY AND
THE TIDAL POTOMAC RIVER. DESPITE THE LOW ASTRONOMICAL
NORMS...MODERATE FLOODING IS LIKELY NEAR TIMES OF HIGH TIDE
WEDNESDAY AFTERNOON THROUGH WEDNESDAY NIGHT. A COASTAL FLOOD
ADVSIROY HAS BEEN ISSUED FOR DC AND WRN SIDE OF CHES BAY FM ANNE
ARUNDEL NWD.

NW WINDS WILL ALLOW FOR TIDAL ANOMALIES TO DECREASE THU.

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...COASTAL FLOOD ADVISORY FROM 7 PM THIS EVENING TO 3 AM EST
THURSDAY FOR DCZ001.
MD...WIND ADVISORY FROM NOON TODAY TO 6 AM EST THURSDAY FOR MDZ501.
FLASH FLOOD WATCH FROM 3 PM EST THIS AFTERNOON THROUGH LATE
TONIGHT FOR MDZ501-502.
COASTAL FLOOD ADVISORY FROM 4 PM THIS AFTERNOON TO 4 AM EST
THURSDAY FOR MDZ007-011-014.
VA...WIND ADVISORY FROM NOON TODAY TO 6 AM EST THURSDAY FOR
VAZ025>030-036>040-503-504.
FLASH FLOOD WATCH FROM 3 PM EST THIS AFTERNOON THROUGH LATE
TONIGHT FOR VAZ503-504.
COASTAL FLOOD ADVISORY FROM 7 PM THIS EVENING TO 3 AM EST
THURSDAY FOR VAZ054.
WV...WIND ADVISORY FROM NOON TODAY TO 6 AM EST THURSDAY FOR WVZ050-
055-501>503-505-506.
FLASH FLOOD WATCH FROM 3 PM EST THIS AFTERNOON THROUGH LATE
TONIGHT FOR WVZ050-055-501>506.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
ANZ530>543.
SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EST THURSDAY FOR
ANZ530>532-535-536-538>540.
GALE WARNING FROM 4 PM THIS AFTERNOON TO 6 AM EST THURSDAY FOR
ANZ530>532-535-536-538>540.
GALE WARNING FROM 4 PM THIS AFTERNOON TO 6 PM EST THURSDAY FOR
ANZ533-534-537-541>543.

$$
PRODUCTS...BAJ/WOODY!

AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

409 AM EST WED JAN 30 2013

.SYNOPSIS...
WELL ABOVE NORMAL TEMPERATURES...GUSTY WINDS AND RAIN SHOWERS
TODAY AHEAD OF A STRONG COLD FRONT WHICH WILL PASS THROUGH LATE
THIS AFTERNOON AND EVENING. MUCH COLDER AIR AND SNOW SHOWERS FOR
THE REMAINDER OF THE WEEK.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WILL ISSUE A WIND ADVISORY TODAY FOR THE HIGHEST RIDGES IN
GARRETT...PRESTON AND TUCKER COUNTIES. LATEST RUC FORECAST
SOUNDINGS ON BUFKIT ARE SHOWING 60-65KTS TODAY JUST ABOVE 2500FT
IN THESE COUNTIES.

PER HPC DESIGNATION OF MOD RISK FOR EXCESSIVE RAINFALL AND
COUNTIES WITH THE LOWEST FFG...WILL ISSUE FLOOD WATCH FOR PORTIONS
OF THE SOUTH AND EAST TODAY AND TONIGHT.

STRONG COLD FRONT WILL MOVE INTO W OHIO AFTER DAWN. SHOWERS AND
SOME STORMS WILL ACCOMPANY THE FRONT AS IT CONTINUES ITS SLOW
EASTWARD PROGRESSION. EXPECT A GOOD SOAKING TODAY WITH ONE- HALF
TO ONE INCH OF RAIN FOR MUCH OF THE REGION. IN THE FLOOD WATCH
COUNTIES...1 TO 2 INCHES OF RAIN IS POSSIBLE WITH THE BULK OF IT
COMING THIS AFTERNOON AND EVENING. THE WATCH MAY NEED TO BE
EXPANDED PARTICULARLY IF A LINE OF STRONG SLOW MOVING CONVECTION
DEVELOPS.

THE OTHER PROBLEM WILL BE THE POTENTIAL FOR STRONG WIND GUSTS
ACROSS THE REST OF MY COUNTIES. LATEST CONVECTIVE OUTLOOK FOR
TODAY PUT MUCH OF THE AREA IN A SLIGHT RISK. THINK THE BEST WAY TO
HANDLE THIS IS TO INCLUDE THE POSSIBILITY OF SEVERE STORMS TODAY
WITH DAMAGING WINDS.

TEMPS WILL REMAIN WELL ABOVE NORMAL TODAY.

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
MUCH COLDER AIR WILL RAPIDLY MOVE IN TONIGHT. LEFT OVER RAIN
SHOWERS WILL CHANGE OVER TO SNOW SHOWERS AS THE NIGHT PROGRESSES.
THINK THE BEST LOCATION FOR ANY ACCUMULATIONS WILL BE ACROSS THE
HIGHER ELEVATIONS. IT DOES NOT APPEAR THAT THE SFC TEMPS WILL
RESPOND QUICK ENOUGH ELSEWHERE TO ALLOW FOR ACCUMULATION.
CONCERNED ABOUT DAMAGING WINDS BEHIND THE FRONT AS WELL. VERY
STRONG CAA...COMBINED WITH PRES RISES OF 6 TO 8 MBS IS PRESENTING
A PERIOD OVERNIGHT THAT MAY REQUIRE A WIND ADVISORY. WILL ALLOW
THE NEXT SHIFT TO TAKE A CLOSER LOOK AT THIS.

RISK FOR SNOW SHOWERS...MAINLY OVER THE FAR NORTH AND
RIDGES...WILL CONTINUE THROUGH THE THURSDAY. TEMPERATURES WILL BE
STEADY OR SLOWLY FALLING WITH GUSTY WINDS CONTINUING.

AT THIS POINT...HAVE VERY LOW CONFIDENCE ON EFFECTS FROM SHORTWAVE
WHICH WILL DIVE SOUTHWARD ACROSS THE REGION THU NIGHT. LATEST
MODEL RUNS ARE HINTING AT SOME ACCUMULATING SNOWS...PARTICULARLY
OVER THE SOUTHERN HALF. THU NIGHT/FRI MORN FORECAST WILL NEED FINE
TUNING AS MODELS GET BETTER HANDLE ON LOCATION OF WAVE.

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
UNCERTAINTY LIES IN THE FORECAST AS MODELS SEEM TO BE IN
DISAGREEMENT. GFS/ECMWF DO SHOW A SHORTWAVE TROUGH MOVING OVER THE
AREA ON THE WEEKEND AND THUS BRINGING A CLIPPER SOUTHEAST WITH THE
GFS BRINGING HIGHER AMOUNTS OF SNOW THAN THE ECMWF. POSSIBLE LAKE
ENHANCED AND/OR TERRAIN ENHANCED SNOW COULD DEVELOP AFTER THE
PASSAGE OF THE QUICK MOVING SYSTEM.

THE GFS BRINGS IN ANOTHER STRONGER CLIPPER OVER THE GREAT LAKES AND
NORTHERN OHIO VALLEY MONDAY NIGHT INTO TUESDAY WHILE THE ECMWF
TRACKS THE SYSTEM MORE NORTHEAST AND BRINGS PRECIPITATION TO OUR AREA
ALONG A COLD FRONT. HIGH PRESSURE BUILDS BEHIND THE SYSTEM LEAVING
THE MID WEEK DRY. HPC TRENDED TOWARDS THE ECMWF RUN THE LATTER PART
OF THE EXTENDED AND THUS FORECAST IS BASED ON GFS/HPC GUIDANCE KEEPING
SLIGHT TO CHANCE POPS.

.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
VFR EXPD OVRNGT. LLVL JET SPEEDS WL BE INCRG OVRNGT AS WELL...WITH
LLWS CONTG INTO WED MRNG. A STG CDFNT WL APRCH FM THE W WED...
BRINGING MVFR SHRA AND GUSTY S WNDS. SOME INSTAB EVIDENT UPSTREAM
TNGT LOOKING AT STLT/MESO/RAOB INSTAB CHART DATA. THIS SHOULD
TRANSITION EWD WED WITH THE CDFNT. TS WL BE PSBL ALG/AHEAD OF THE
CDFNT BUT LEFT OUT OF TAFS FOR NOW WITH RELATIVELY LOW PROB OF
OCCURRANCE AT ANY ONE POINT. WL RE-EVALUATE FOR LTR TAFS. EXPT
INITIAL WSHFT TO SW WITH PREFRONTAL TROF LT AFTN...THEN TO THE W
WED EVE/NGT AS THE CDFNT MOVES THRU. WNDS WL BE GUSTY AS WELL
BEHIND THE FNT.

.OUTLOOK.../THURSDAY THROUGH SUNDAY/...
PERIODIC RESTRICTION ARE EXPD THRU THE PD AS SVRL DISTURBANCES
MOVE THRU IN COLD W-NW FLOW. GUSTY W WNDS ARE ALSO EXPTD THRU THU.

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FLOOD WATCH FROM 1 PM EST THIS AFTERNOON THROUGH THURSDAY
MORNING FOR MDZ001.
WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR MDZ001.
OH...NONE.
PA...FLOOD WATCH FROM 1 PM EST THIS AFTERNOON THROUGH THURSDAY
MORNING FOR PAZ016-023-031-073>076.
WV...FLOOD WATCH FROM 1 PM EST THIS AFTERNOON THROUGH THURSDAY
MORNING FOR WVZ012-021>023-041.
WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR WVZ023-041.

AREA FORECAST DISCUSSION

NWS BALTIMORE MD/WASHINGTON DC

400 AM EST WED JAN 30 2013

.SYNOPSIS...

LOW PRESSURE IS CENTERED OVER MICHIGAN. FROM THIS A WARM EXTENDS
ACROSS PENNSYLVANIA WHILE A COLD FRONT EXTENDS FROM INDIANA TO
ARKANSAS. THE COLD FRONT WILL MOVE THROUGH THE MID ATLANTIC STATES
THIS EVENING. ANOTHER COLD FRONT WILL MOVE THROUGH THE REGION
FRIDAY...FOLLOWED BY HIGH PRESSURE SATURDAY.

.NEAR TERM /TODAY/...

AS OF 08Z...COLD FRONT IS OVER THE UPR MIDWEST WITH A PREFRONTAL
BAND OF THUNDERSTORMS ASSOCIATED WITH A STRONG GULF PLUME EXTENDS
FROM THE MS DELTA TO DETROIT. A WIDE SWATH OF TRAILING STRATIFORM IS
OVER WRN IL AND IN.

.SHORT TERM /TONIGHT/...

PRECIP SLOWLY CUTS OF WITH STRATIFORM TRAILING MAIN BAND
FOR A FEW HOURS. UPSLOPE SNOW OF ONLY A COUPLE INCHES. NO WINTER
ADVISORY EXPECTED.

.LONG TERM /THURSDAY THROUGH TUESDAY/...

AFTR TUE AND TDA`S VERY WARM TEMPS THE RGN WL RETURN TO MORE
NORMAL LATE JAN/ERLY FEB TEMPS FOR THE XTND PD.

HIGH PRES WL BUILD INTO THE RGN FRI AFTN AND SAT. HIGHS GNRLY IN
THE U30S E OF THE MTNS. LOWS IN THE 20S.

HIGHS CONT IN THE U30S/L40S SUN THRU TUE. LOWS IN THE MU20S.

.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...

IFR STILL POSSIBLE THROUGH MID MORNING. SLY LOW LEVEL WIND SHEAR
INCREASES TODAY PEAKING TONIGHT JUST AHEAD OF A COLD FRONT. CHANCES
FOR THUNDER WITH VERY GUSTY WINDS...ON THE ORDER OF 50 KT. WINDS
SHIFT WEST AND DECREASE LATE TONIGHT.

GUSTY NW WINDS XPCTD THU. SKIES/CIGS SHOULD BE VFR. VFR CONDITIONS
ARE EXPECTED MOST OF THE TIME THU NIGHT THROUGH SUNDAY.

.MARINE...

SLY GALE EXPECTED BY LATE AFTERNOON CONTINUING UNTIL THE COLD FRONT
CROSSES LATE TONIGHT.

HIGH PRES BLDG INTO THE WATERS WL LKLY CONT TO CAUSE STRONG WIND
GUSTS DURG THU. HV ISSUED A GALE WRNG FOR CHES BAY/LWR TIDAL
PTMC...AND A STRONG SCA FOR THE RMDR OF THE WATERS.

A COLD FRONT WILL PASS THROUGH THURSDAY NIGHT, GUSTY WINDS ARE
EXPECTED BEHIND THE FRONT FRIDAY. HIGH PRES OVR THE WATERS SAT.
ANOTHER COLD FRONT MAY IMPACT THE WATERS SUNDAY.

.TIDES/COASTAL FLOODING...

A SOUTHERLY FLOW WILL INCREASE TODAY WITH GUSTS AROUND 35 KNOTS
DURING THE AFTERNOON AND EVENING HOURS. THE STRONG SOUTHERLY FLOW
WILL PUSH WATER UP THE MARYLAND PORTION OF THE CHESAPEAKE BAY AND
THE TIDAL POTOMAC RIVER. DESPITE THE LOW ASTRONOMICAL
NORMS...MODERATE FLOODING IS LIKELY NEAR TIMES OF HIGH TIDE
WEDNESDAY AFTERNOON THROUGH WEDNESDAY NIGHT. A COASTAL FLOOD
HEADLINE DECISION WILL BE MADE SHORTLY.

NW WINDS WILL ALLOW FOR TIDAL ANOMALIES TO DECREASE THU.

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...COASTAL FLOOD WATCH FROM 2 PM EST THIS AFTERNOON THROUGH LATE
TONIGHT FOR DCZ001.
MD...WIND ADVISORY FROM NOON TODAY TO 6 AM EST THURSDAY FOR MDZ501.
FLASH FLOOD WATCH FROM 3 PM EST THIS AFTERNOON THROUGH LATE
TONIGHT FOR MDZ501-502.
COASTAL FLOOD WATCH FROM 2 PM EST THIS AFTERNOON THROUGH LATE
TONIGHT FOR MDZ007-011-013-014-016>018.
VA...WIND ADVISORY FROM NOON TODAY TO 6 AM EST THURSDAY FOR
VAZ025>030-036>040-503-504.
FLASH FLOOD WATCH FROM 3 PM EST THIS AFTERNOON THROUGH LATE
TONIGHT FOR VAZ503-504.
COASTAL FLOOD WATCH FROM 2 PM EST THIS AFTERNOON THROUGH LATE
TONIGHT FOR VAZ052>055-057.
WV...WIND ADVISORY FROM NOON TODAY TO 6 AM EST THURSDAY FOR WVZ050-
055-501>503-505-506.
FLASH FLOOD WATCH FROM 3 PM EST THIS AFTERNOON THROUGH LATE
TONIGHT FOR WVZ050-055-501>506.
MARINE...SMALL CRAFT ADVISORY FROM 7 AM THIS MORNING TO 4 PM EST THIS
AFTERNOON FOR ANZ530>543.
SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EST THURSDAY FOR
ANZ530>532-535-536-538>540.
GALE WARNING FROM 4 PM THIS AFTERNOON TO 6 AM EST THURSDAY FOR
ANZ530>532-535-536-538>540.
GALE WARNING FROM 4 PM THIS AFTERNOON TO 6 PM EST THURSDAY FOR
ANZ533-534-537-541>543.

$$
PRODUCTS...BAJ/WOODY!

AREA FORECAST DISCUSSION

NWS GRAND RAPIDS MI

1232 AM EST WED JAN 30 2013

.SYNOPSIS...
ISSUED AT 348 PM EST TUE JAN 29 2013

.UPDATE...
ISSUED AT 817 PM EST TUE JAN 29 2013

.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 348 PM EST TUE JAN 29 2013

.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 348 PM EST TUE JAN 29 2013

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1228 AM EST WED JAN 30 2013

VERY COMPLEX AVIATION FORECAST THE NEXT 24 HOURS...AS A LOW
PRESSURE CENTER MOVES THROUGH THE AREA. CHANGEABLE AVIATION
CATEGORIES AND WIND DIRECTION WILL MAKE FOR A COMPLICATED
FORECAST. IN GENERAL...AVIATION CONDITIONS WILL DIP OVERNIGHT BACK
INTO IFR AT MOST SITES AS THE WINDS SLACK OFF A BIT WITH THE LOW
AND HEAVIER RAIN MOVES BACK IN. A GRADUAL IMPROVEMENT SHOULD BE
SEEN ON WEDNESDAY...BUT WE SHOULD NOT IMPROVE BEYOND MVFR THROUGH
THE DAY. RAIN WILL BEGIN TO CHANGE TO SNOW FROM WEST TO EAST
DURING THE EVENING HOURS.

.MARINE...
ISSUED AT 348 PM EST TUE JAN 29 2013

.HYDROLOGY...
ISSUED AT 957 PM EST TUE JAN 29 2013

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...FLOOD WATCH THROUGH THIS AFTERNOON FOR MIZ039-040-045-046-051-
052-057>059-065>067-072>074.

LM...SMALL CRAFT ADVISORY UNTIL 7 AM EST THURSDAY FOR LMZ844>849.

UPDATE...LAURENS
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...93
AVIATION...DUKE
HYDROLOGY...DUKE
MARINE...OSTUNO

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

1205 AM EST WED JAN 30 2013

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 504 PM EST TUE JAN 29 2013

WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
NE MANITOBA THROUGH THE PLAINS INTO NEW MEXICO. WEAK SHRTWVS
EMBEDDED IN THE SW FLOW FROM THE SRN PLAINS INTO THE GREAT LAKES
SUPPORTED AREAS OF SHRA/TSRA NEAR A SFC FRONT EXTENDING FROM NE WI
THROUGH CNTRL MO AND INTO CNTRL OK. THE MAIN SHRTWV WAS REMAINED
NEAR THE BASE OF THE TROUGH...MOVING TOWARD THE TX/OK PANHANDLE.
PCPN HAD DIMINISHED OVER UPPER MICHIGAN WITH MAINLY SOME SCT LIGHT
SHOWERS MOVING THROUGH FAR SRN UPPER MI. WEST WINDS AND SLIGHTLY
DRIER AIR BEHIND A TROUGH SLIDING TO NEAR P53-ISQ HAS BROUGHT
IMPROVED VISIBILITIES THROUGH THE CNTRL AND WEST CWA.

ALTHOUGH THE 12Z ECMWF WAS A BIT SLOWER THAN THE 12Z GFS...THE MODELS
WERE IN RELATIVELY GOOD AGREEMENT WITH REGARD TO OVERALL PCPN/SNOW
POTENTIAL ACROSS THE CWA. ALTHOUGH THE 12Z NAM HAD SHIFTED THE
HEAVIER QPF AXIS WELL TO THE EAST...THE 18Z RUN HAS COME BACK INTO
BETTER AGREEMENT WITH THE GLOBAL MODELS. MODELS DIFFICULTY IN
HANDLING THE CONVECTION AND HEAVY RAIN NEAR THE FRONT MAY ACCOUNT
FOR A PORTION OF THE INCONSISTENCY AND VARIABILITY AND STILL LEADS
GREATER THAN USUAL UNCERTAINTY. ALTHOUGH THERE IS MODERATE
CONFIDENCE WITH THE MULTI-MODEL BLEND OF THE GFS/ECMWF/NAM/REG-GEM
USED FOR QPF...TIMING OF THE HEAVIER PCPN ONSET MAY BE A BIT DELAYED
GIVEN ECMWF/NAM TRENDS.

THE STRONGEST DYNAMICS ARE EXPECTED TO DEVELOP BTWN 12Z-18Z/WED AS
THE NM SHRTWV LIFTS TOWARD THE GREAT LAKES. A COUPLED UPPER LEVEL
JET STRUCTURE AND RESULTING STRONG 800-600 MB FGEN WILL SUPPORT A
PERIOD OF MODERATE TO HEAVY PCPN IN THE REGION...WITH THE BEST
CHANCE FOR HEAVY SNOW OVER THE SE HALF OF UPPER MI. EXPECT A SHARP
NW EDGE OF THE PCPN BAND DUE TO STRONG DESCENDING FGEN CIRCULATION
BRANCH WHICH REDUCES CONFIDENCE IN PCPN AMOUNTS THROUGH CNTRL UPPER
MI. QPF VALUES IN THE 0.30 TO 0.60 INCH RANGE WITH SNOW/WATER RATIO
VALUES NEAR 16/1 SUPPORTS GENERALLY 4 TO 8 INCH SYNOPTIC
SNOW...GREATEST OVER THE FAR S AND EAST. LAKE ENHANCED SNOW WILL
GENERALLY BE LIGHT EARLY WED WITH LOW INVERSION HEIGHTS NEAR 4K FT
AND 850 MB TEMPS ONLY NEAR -10C BUT BY WED AFTERNOON SNOWFALL RATES
OVER N CNTRL AND FAR WEST NEAR IWD SHOULD INCREASE AS 850 MB TEMPS
FALL TO NEAR -16C. ALTHOUGH UPSLOPE FLOW SHOULD ENHANCE SNOWFALL
RATES...CYCLONIC 350 FLOW MAY ALSO LEAD TO GREATER AMOUNTS NEAR THE
SHORE WED AFTERNOON.

FCST CONFIDENCE WAS HIGH ENOUGH TO UPGRADE WATCHES TO WARNINGS OVER
THE EAST HALF BUT WITH AMOUNTS ONLY IN THE 2 TO 5 INCH RANGE OVER
MARQUETTE AND DICKINSON COUNTIES THROUGH WED AND PROXIMITY TO THE
EDGE OF THE SYNOPTIC PCPN...AN ADVY WAS ISSUED.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 446 PM EST TUE JAN 29 2013

INITIAL PART OF THE LONG TERM FORECAST IS HIGHLY DEPENDENT ON THE
TRACK OF THE SHORTWAVE RIDING UP THE UPPER TROUGH OVER THE CENTRAL
CONUS AND THE ASSOCIATED LOW DEVELOPING IN NORTHERN LOWER MI AND
THEN SHIFTING NORTHEAST INTO QUEBEC ON WEDNESDAY NIGHT. THE SHORT
TERM DISCUSSION COVERS MUCH OF THE DETAILS WITH THIS SYSTEM AND THE
MAIN FEATURE TO CAPTURE IN THE LONG TERM WITH THIS SYSTEM IS THE
DIMINISHING TREND IN THE POPS/QPF OVER THE EASTERN CWA.

BEHIND THIS FEATURE...EXPECT COLD AIR TO SURGE SOUTHEAST OVER THE
UPPER GREAT LAKES REGION AND REMAIN INTO THE WEEKEND. THIS COLD
AIR...H850 TEMPS IN THE LOW -20S CELSIUS...MOVING ACROSS THE
RELATIVELY WARM LAKE SUPERIOR WATERS WILL LEAD TO PERSISTENT LAKE
EFFECT. AMOUNTS AND LOCATIONS WILL LARGELY DEPEND ON WIND DIRECTION
AND DEEPER MOISTURE DURING THIS PERIOD.

FOR WEDNESDAY NIGHT...LAKE EFFECT WILL BE INCREASING IN INTENSITY
OVER THE WEST THROUGH THE NIGHT DUE TO INCREASING COLD AIR AND
DEEPER MOISTURE ARRIVING FROM THE NORTHWEST. THIS WILL PUSH
INVERSION HEIGHTS TOWARDS 10KFT OVER THE WITH WESTERN AREAS AND
WITH DELTA-T VALUES AROUND 23...LAKE INDUCED CAPE VALUES RISE
TOWARDS 500-700 J/KG. EXPECT THE HIGHEST AMOUNTS...2-6 INCHES...IN
THE NORTH-NORTHWEST WIND FAVORED LOCATIONS. OVER THE
EAST...FORECAST IS A LITTLE MORE UNCERTAIN DUE TO THE SYSTEM...BUT
THEY TOO SHOULD TRANSITION TO LAKE EFFECT. WITH MOISTURE HELP FROM
THE SYSTEM...SNOW AMOUNTS WILL BE HIGHER THERE ESPECIALLY IN THE
LOCATIONS FAVORED BY NORTH-NORTHWEST WINDS. THE HIGHEST AMOUNTS WILL
LIKELY OCCUR THROUGH THE NIGHT OVER THE WESTERN PORTIONS OF ALGER
COUNTY...WHERE COASTAL EFFECTS FROM NORTHERN MARQUETTE COUNTY WILL
LIKELY INCREASE CONVERGENCE THERE AND THUS SNOWFALL AMOUNTS. HAVE
TRENDED POPS TOWARDS THIS IDEA FOR THE WEDNESDAY NIGHT PERIOD.

WITH THE COLD AIR CONTINING TO FLOW OVER THE AREA ON
THURSDAY...MULTI-BAND LAKE EFFECT WILL BE AIDED BY THE INCREASED MID
LEVEL MOISTURE MOVING OVER THE AREA BEHIND A SHORTWAVE DROPPING
THROUGH THE UPPER/MID MISSISSIPPI VALLEY ON THURSDAY. THIS WILL LEAD
TO INVERSION HEIGHTS IN THE 7-10KFT RANGE OVER THE AREA...WITH THE
HIGHEST VALUES OVER THE EAST. THE MAIN DETERMINING FACTOR FOR SNOW
AMOUNTS IN THE NORTHWEST WIND FAVORED LOCATIONS ON THURSDAY WILL BE
WHEN THE DGZ FALLS BELOW OR TO THE BOTTOM OF THE CLOUD LAYER. THIS
WILL OCCUR FIRST OVER THE WEST AND THEN OVER THE EAST LATE IN THE
DAY. THIS WILL LEAD TO A TRANSITION TO LOWER SNOW RATIOS WITH THE
TRANSITION TO MORE COLUMNS THAT IS USUALLY SEEN IN COLD/ARCTIC AIR
MASSES. WITH THE WINDS BACKING TO MORE OF A NORTHWEST WIND
DIRECTION THROUGH DAY...WOULD EXPECT THERE TO BE A COUPLE ENHANCED
LOCATIONS DUE TO INCREASED CONVERGENCE. AT THIS TIME...WOULD EXPECT
IT TO BE OVER GOGEBIC/ONTONAGON AND ALGER COUNTIES.

HIGH PRESSURE SLIDING SOUTHEAST FROM THE DAKOTAS ON THURSDAY NIGHT
WILL LEAD TO BACKING WINDS TO THE WEST OVER THE WESTERN LAKE AND
WEST-NORTHWEST OVER THE EAST. THIS WILL CONTINUE INTO FRIDAY AS THE
HIGH MOVES INTO THE MID MISSISSIPPI VALLEY AND LEADS TO WEST TO
WEST-SOUTHWEST WINDS. THESE WINDS WILL BE AIDED BY A WEAK LOW
DEVELOPING OVER EASTERN LAKE SUPERIOR. COLD AIR IS STILL IN THE
LOWER -20S CELSIUS DURING THE PERIOD...SO THE LAKE EFFECT WILL BE
ONGOING. BUT...WITH THE HIGH REDUCING THE MOISTURE ABOVE H850 AND
INCREASING THE SUBSIDENCE INVERSION EXPECT THERE TO BE A GRADUAL
DECREASE IN INTENSITY DURING THAT TIME FRAME.

DEFINITELY THINK THAT THE NORTH-NORTHWEST WIND LOCATIONS WILL NEED
LAKE EFFECT SNOW ADVISORIES DURING THIS WEDNESDAY NIGHT INTO
THURSDAY NIGHT PERIOD. WARNINGS ARE A LITTLE MORE UNCERTAIN DUE TO
THE LIMITED PERIODS OF THE BEST OMEGA WITHIN THE DGZ. OUT OF ALL OF
THE LOCATIONS...WOULD THINK THAT ALGER COUNTY WOULD HAVE THE BEST
OPPORTUNITY OF SEEING WARNING SNOWFALL AMOUNTS. OPTED TO GO AHEAD
AND ISSUE THE LAKE EFFECT SNOW ADVISORY FOR GOGEBIC/ONTONAGON
COUNTIES AND THE REST OF THE FAVORED AREAS WILL NEEDED TO BE ADDED
IN THE NEXT 12-24HRS.

HEADING INTO THE WEEKEND...THE COLDER AIR WILL BEGIN TO LOSE IT/S
GRIP ON THE AREA AS THE UPPER TROUGH SHIFTS TO THE EAST AND AREA
COMES UNDER NORTHWEST FLOW ALOFT. THESE PERIODS COME DOWN TO
TIMING/LOCATING SHORTWAVES MOVING THROUGH THE FLOW AND HAVE TRIED
TO FOLLOW A GENERAL CONSENSUS FOR TIMING THESE WAVES. FIRST ONE
LOOKS TO MOVE THROUGH THE AREA ON SATURDAY NIGHT AND AGAIN ON
SUNDAY NIGHT INTO MONDAY. BETWEEN THOSE TWO PERIODS...THERE SHOULD
BE ENOUGH COLD AIR TO SUPPORT LAKE EFFECT SNOW IN AREAS FAVORED BY
NORTHWEST WINDS.

WITH THE COLD AIR SPILLING INTO THE AREA...A COOLING TREND IS
EXPECTED FOR THE SECOND HALF OF THE WORK WEEK. FRIDAY CONTINUES TO
LOOK LIKE THE COLDEST DAY OVER THE NEXT 7 DAYS...WITH HIGHS OVER THE
WEST STRUGGLING TO RISE ABOVE 0 DEGREES. THIS COLD AIR WILL CAUSE
WIND CHILL VALUES TO APPROACH -25 ON ON THURSDAY NIGHT INTO
FRIDAY MORNING AND AGAIN FRIDAY NIGHT INTO SATURDAY MORNING OVER THE
INTERIOR WEST HALF OF UPPER MICHIGAN. TEMPERATURES WILL THEN WARM
BACK TO MORE NORMAL VALUES BY THE FIRST PART OF NEXT WEEK.
&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1205 AM EST WED JAN 30 2013

CONFIDENCE IN THIS FORECAST CONTINUES TO BE LOW AS DRIER AIR SEEMS
TO BE WINNING OVER UPSLOPE LOW CIGS THAT WERE EXPECTED TO REMAIN AND
DEVELOP OVERNIGHT. MVFR CONDITIONS WILL CONTINUE AT CMX THROUGH THE
PERIOD. AT IWD...LAKE ENHANCEMENT KICKS IN WITH VISIBILITY FALLING
TO IFR BY WED MORNING AND STAYING THERE THROUGH THE REST OF THE
PERIOD WITH UPSLOPE HELPING THE LAKE EFFECT. MVFR CONDITIONS AT SAW
WILL GIVE WAY TO IFR BY WED MORNING AS SYSTEM SNOW MOVES IN. AS
WINDS GO NNW BY EVENING...CONDITIONS SHOULD IMPROVE TO MVFR AT SAW
AS SYSTEM SNOW MOVES OUT.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 504 PM EST TUE JAN 29 2013

A DEEPENING LOW PRESSURE SYSTEM MOVING THROUGH LAKE HURON WEDNESDAY
AND TO THE NORTHEAST BY WEDNESDAY NIGHT WILL LIKELY BRING A PERIOD
OF N TO NW GALES TO CENTRAL AND EASTERN LAKE SUPERIOR LATE TONIGHT
INTO WEDNESDAY NIGHT. WINDS/WAVES COMBINED WITH ARCTIC AIR SETTLING
OVER THE AREA WILL RESULT IN FREEZING SPRAY...POSSIBLY HEAVY AT
TIMES LATE WEDNESDAY INTO FRIDAY.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY FROM 3 AM TO 9 PM CST WEDNESDAY FOR
MIZ011.

WINTER STORM WARNING UNTIL 10 PM EST /9 PM CST/ THIS EVENING FOR
MIZ012>014.

WINTER STORM WARNING FROM 4 AM EARLY THIS MORNING TO 7 AM EST
THURSDAY FOR MIZ006-007-085.

LAKE EFFECT SNOW ADVISORY FROM 7 AM EST /6 AM CST/ THIS MORNING
TO 7 AM EST /6 AM CST/ FRIDAY FOR MIZ002-009.

WINTER WEATHER ADVISORY FROM 7 AM THIS MORNING TO 1 AM EST
THURSDAY FOR MIZ005.

LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 7 PM THIS EVENING TO 7 AM EST
FRIDAY FOR LSZ265>267.

GALE WARNING FROM 10 AM THIS MORNING TO 4 AM EST THURSDAY FOR
LSZ267.

GALE WARNING FROM 5 AM EARLY THIS MORNING TO 4 AM EST THURSDAY
FOR LSZ264>266.

HEAVY FREEZING SPRAY WARNING FROM 1 PM EST /NOON CST/ THIS
AFTERNOON TO 7 AM EST /6 AM CST/ FRIDAY FOR LSZ162-263-264.

GALE WARNING FROM 5 AM EARLY THIS MORNING TO 10 PM EST THIS
EVENING FOR LSZ263.

LAKE MICHIGAN...
NONE.
&&

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

AREA FORECAST DISCUSSION

NWS BILLINGS MT

842 PM MST TUE JAN 29 2013

.SHORT TERM...VALID FOR WED AND THU...

INFRARED SATELLITE IMAGES HAVE SHOWN SIGNIFICANT CLOUD-TOP WARMING
WITH THE CONVECTIVE ELEMENTS ACROSS SOUTHEASTERN MT SINCE ABOUT 22
UTC...AND OBSERVATIONS FROM MILES CITY AND BAKER HAVE BEEN SHOWING
AN UPTICK IN VISIBILITY THE LAST FEW HOURS TOO. WE ARE COMFORTABLE
DROPPING THE WINTER WEATHER ADVISORY FOR CUSTER COUNTY A FEW HOURS
EARLY AS LOW- AND MID-LEVEL STABILIZATION IS SHUTTING DOWN MOST OF
THE SNOW SHOWER ACTIVITY IN THAT AREA. PLUS...THE CORE OF PRESSURE
RISES THAT WAS RESPONSIBLE FOR GUSTY WINDS IS EXITING INTO WESTERN
SD AS OF 03 UTC. WIND CHILLS ARE DOWN INTO THE -20 F RANGE ALREADY
THOUGH...AND THERE SHOULD BE ENOUGH SURFACE GRADIENT TO KEEP WINDS
CLOSE TO 10 MPH THROUGH AT LEAST 09 UTC...SO WE WILL KEEP THE WIND
CHILL ADVISORY FOR PART OF SOUTHEASTERN MT IN EFFECT. MEANWHILE...
WE DECIDED TO END THE WIND CHILL ADVISORY A FEW HOURS EARLY IN THE
JUDITH GAP AREA...WHERE WINDS HAVE DIMINISHED AND TEMPERATURES ARE
ACTUALLY RISING A BIT WITH AN INCREASE IN CLOUDS.

THE FORECAST WAS ALSO UPDATED TO REDUCE POPS IN SOME SPOTS FOR THE
NIGHTTIME HOURS OUT OF RESPECT TO THE 18 UTC MULTI-MODEL CONSENSUS
AND THE 00 UTC NAM AND RAP SOLUTIONS...ALL OF WHICH SUGGEST LITTLE
IN THE WAY OF QPF IN MOST AREAS THROUGH 12 UTC. HOWEVER...THE NEXT
WAVE OF SNOW WILL BE DRIVEN BY WARM AIR ADVECTION ALOFT IDENTIFIED
BY FORCING ON ISENTROPIC SURFACES...AND SUBJECTIVE OBSERVATIONS DO
SUGGEST THAT MODELS ARE OFTEN TOO SLOW TO GENERATE QPF WITH EVENTS
LIKE THIS ONE. THUS...WE NEEDED TO KEEP SOME 20 TO 30 PERCENT POPS
FOR MOST LOWER ELEVATIONS AFTER 06 UTC. FINALLY...SURFACE PRESSURE
FALLS OF 3 HPA/3 HOURS ARE ALREADY BEING OBSERVED IN NORTH CENTRAL
MT AS OF MID EVENING AS WARM AIR ADVECTION RAMPS UP ALOFT. AS THIS
TIGHTENS THE LOW-LEVEL PRESSURE GRADIENT AROUND LIVINGSTON...WINDS
COULD GET STRONG LATE TONIGHT AND WED MORNING...WHICH IS SUPPORTED
BY THE 18 UTC MAV AND 00 UTC MET GUIDANCE. WE THUS INCREASED WINDS
IN THE GRIDDED FORECAST NEAR LIVINGSTON FROM 09 TO 18 UTC...AND IT
WOULDN/T BE TOO SURPRISING IF WE END UP NEEDING A WIND ADVISORY IN
THAT AREA BEFORE ALL IS SAID AND DONE. SCHULTZ

.LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE...

THE EXTENDED FORECAST BEGINS ON FRIDAY WITH THE ARCTIC AIRMASS
FINALLY RETREATING EASTWARD INTO THE DAKOTAS. NORTHWESTERLY FLOW
WILL REMAIN IN PLACE ALOFT...WITH A SHORTWAVE TROUGH PASSING
ACROSS THE FORECAST AREA DURING THE DAY FRIDAY. THIS WILL CAUSE A
SURFACE LOW TO TRACK FROM CANADA ACROSS NORTHEAST MONTANA...ACTING
TO TIGHTEN THE PRESSURE GRADIENT ACROSS THE FORECAST AREA. THIS
SURFACE PRESSURE GRADIENT WILL COMBINE WITH WARM ADVECTION AT
MOUNTAIN TOP LEVEL AND WESTERLY 700 MB WINDS UP TO 45 KTS TO
CREATE A FAVORABLE PERIOD FOR STRONG WINDS FROM LIVINGSTON TO BIG
TIMBER TO NYE. GUSTY WINDS WESTERLY WINDS WILL SPREAD ACROSS THE
PLAINS BEHIND THE SURFACE FRONT AS WINDS TURN TO THE NORTHWEST.
PRECIPITATION CHANCES WILL BE LIMITED FROM BILLING WEST DUE TO
STRONG DOWNSLOPE FLOW COUNTERACTING THE QG FORCING FROM THE
WAVE...BUT SNOW SHOWERS WILL HAVE A BETTER CHANCE OF DEVELOPING
EAST OF BILLINGS WHERE THE DOWNSLOPE WILL HAVE LESS INFLUENCE.

THE NEXT SYSTEM OF INTEREST WILL BE ANOTHER WIND EVENT IN THE
SUNDAY TIME FRAME AS ANOTHER SHORTWAVE TRAVERSES THE FORECAST
AREA. HAVE HIT THE WINDS A LITTLE HARDER IN THE FORECAST GRIDS TO
SHOW THIS TREND. OTHERWISE TEMPERATURES WILL REMAIN SEASONABLE TO
SLIGHTLY ABOVE AVERAGE THROUGH THE EXTENDED FORECAST. THE WEATHER
PATTERN LOOKS PRETTY QUIET TO START NEXT WEEK AS RIDGE BUILDS IN
ALOFT. CHURCH
&&

.AVIATION...

IFR TO MVFR CONDITIONS DUE TO LOW CEILINGS AND VISIBILITY IN SNOW
WILL LINGER OVER EASTERN ROUTES FROM KMLS TO K97M THROUGH ABOUT
05Z WITH GRADUAL IMPROVEMENT TO MAINLY VFR. STRONG NW WINDS IN
THESE AREAS WILL ALSO DECREASE TO UNDER 15 KTS AFTER 07Z. VFR WILL
OTHERWISE PREVAIL ACROSS THE REST OF THE FORECAST AREA OVERNIGHT.
STRONG SW WINDS WILL DEVELOP IN THE KLVM VICINITY AFTER 09Z WITH
GUSTS NEAR 40 KTS POSSIBLE. UNSETTLED CONDITIONS WILL DEVELOP
AGAIN ON WEDNESDAY WITH SOME AREAS FROM KBIL EAST AND SOUTH
EXPECTED TO HAVE MVFR TO IFR CONDITIONS. MOUNTAINS MAY BE OBSCURED
ON WEDNESDAY AS WELL. BT

.PRELIMINARY POINT TEMP/POPS...

WED THU FRI SAT SUN MON TUE
-----------------------------------------------------------
BIL 005/023 007/027 022/043 023/045 028/049 028/046 026/048
36/S 65/J 22/W 00/B 01/N 11/N 11/B
LVM 009/035 020/038 028/046 025/048 030/049 029/046 030/048
56/O 75/W 22/W 11/N 11/N 11/N 11/N
HDN 002/020 005/022 018/043 017/044 020/047 025/043 023/045
38/S 87/J 22/W 00/B 01/U 11/U 11/U
MLS 904/008 908/010 009/035 016/038 019/041 023/039 023/041
26/S 65/J 22/J 10/B 01/U 11/B 11/U
4BQ 901/014 902/016 010/039 016/041 020/043 024/041 021/043
46/S 76/J 22/J 00/U 00/U 11/B 11/U
BHK 909/002 915/006 000/034 017/034 019/037 020/037 021/039
64/S 42/J 22/J 10/B 00/U 01/B 11/B
SHR 004/022 005/026 019/042 016/046 017/048 023/044 025/046
37/S 87/J 22/J 00/U 00/U 11/U 11/U

.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...WIND CHILL ADVISORY IN EFFECT UNTIL 9 AM MST WEDNESDAY FOR
ZONES 32-33-37.
WINTER WEATHER ADVISORY IN EFFECT FROM 6 AM WEDNESDAY TO NOON
MST THURSDAY FOR ZONES 38-57-58.
WY...WINTER WEATHER ADVISORY IN EFFECT FROM 6 AM WEDNESDAY TO NOON
MST THURSDAY FOR ZONES 98-99.

$$
WEATHER.GOV/BILLINGS

AREA FORECAST DISCUSSION

NWS HASTINGS NE

1201 AM CST WED JAN 30 2013

.AVIATION...06Z KGRI TAF. THE BACK END OF THE SNOW SHIELD WILL
CONTINUE TO SLIDE SOUTHEAST AND EXPECT THE SNOW SHOULD COME TO AN
END AT KGRI BY AROUND 08Z. VISIBILITY AND CEILINGS SHOULD ALSO
SHOW SOME IMPROVEMENT ONCE THE SNOW MOVES OUT. HOWEVER...THE WIND
WILL REMAIN GUSTY OUT OF THE NORTHWEST THROUGH AT LEAST MID
AFTERNOON.

.PREV DISCUSSION... /ISSUED 1045 PM CST TUE JAN 29 2013/

UPDATE...RADAR RETURNS FROM KUEX THROUGH THE PAST HOUR OR SO
INDICATE BANDED PRECIPITATION CONTINUING OVER THE SOUTHEASTERN
ONE-THIRD OF THE CWA. ADVISORY WAS RIGHT ON FOR THE MOST
PART...EXCEPT INCREASED SNOWFALL RATES WERE ALSO BEING INDICATED
OVER NORTH CENTRAL KANSAS AND AS A RESULT...OPTED TO EXTEND THE
ADVISORY TO ALSO INCLUDE MITCHELL...OSBORNE...AND SMITH COUNTIES
IN KANSAS...AS WELL AS WEBSTER COUNTY IN NEBRASKA. ALSO...ALTHOUGH
IT APPEARS THE HEAVIEST SNOWFALL SHOULD BE COMING TO AN END AROUND
01Z...THE ENDING TIME APPEARED A LITTLE TOO CLOSE FOR COMFORT WITH
RESPECT WITH THE HEADLINE. IN ADDITION...AN INCREASING NORTH WIND
IS ALSO EXPECTED TO PROMOTE RESTRICTED VISIBILITY IN BLOWING SNOW
THROUGH SUNRISE WEDNESDAY. GIVEN ALL THIS...WENT AHEAD AND ALSO
EXTENDED THE ADVISORY TO 12Z.

PREV DISCUSSION... /ISSUED 728 PM CST TUE JAN 29 2013/

UPDATE...EVENING UPPER AIR ANALYSIS INDICATES A LONGWAVE TROUGH
OVER THE CENTRAL CONUS...WITH RIDGING OVER THE EAST AND WEST. MID
AND UPPER LEVEL JET ENERGY EXTENDS SOUTH/SOUTHEAST FROM SOUTHWEST
CANADA INTO THE FOUR CORNERS REGION...AND THEN EAST INTO THE
SOUTHERN PLAINS BEFORE TURNING NORTHEAST ACROSS PORTIONS OF THE
CENTRAL PLAINS AND MISSISSIPPI VALLEY. ALTHOUGH THE PRIMARY AXIS
OF THIS JET ENERGY REMAIN JUST EAST/SOUTHEAST OF OUR CWA...RAP
DATA DOES SUGGEST WIND SPEEDS GENERALLY RANGING FROM 50-100KTS IN
EXISTENCE FROM WEST TO EAST ACROSS OUR CWA AROUND 400MB...WITH THE
STRONGEST WIND RESIDING ACROSS OUR EAST. WATER VAPOR IMAGERY SHOWS
INCREASED VALUES OF MID LEVEL MOISTURE EXTENDING FROM EASTERN
TEXAS...NORTHEAST INTO THE MID MISSISSIPPI VALLEY...AND A MID
LEVEL DRY INTRUSION WORKING INTO THE CENTRAL PLAINS. AT THE
SURFACE A COLD FRONT IS NOTED EXTENDING FROM CENTRAL
MISSOURI...SOUTHWEST INTO PORTIONS OF KANSAS...OKLAHOMA AND TEXAS.
OUR CWA IS CURRENTLY ON THE BACK SIDE OF THIS FRONT WITH A
NORTHERLY LOW LEVEL WIND FIELD PREVAILING ACROSS THE AREA AS A
RESULT. RADAR DATA FROM KUEX INDICATES BANDED PRECIPITATION OVER
THE SOUTHEASTERN HALF OF OUR CWA...HOWEVER COMMUNICATION WITH
OBSERVERS HAVE YIELDED LITTLE MORE THAN TRACE REPORTS OF SNOWFALL
ACCUMULATION THIS EVENING...ALTHOUGH ACCUMULATION IS UNDOUBTEDLY
BEGINNING TO OCCUR ALONG AND EAST OF HIGHWAY 281 NOW.

THE CURRENT THINKING IS THAT THIS AREA OF BANDED PRECIPITATION
WILL CONTINUE SHIFTING EAST/NORTHEAST ALONG WITH THE PRIMARY AXIS
OF MID LEVEL FRONTOGENESIS THROUGH TONIGHT...WITH PRECIPITATION
RATES INCREASING AS THE AFOREMENTIONED MID LEVEL FRONTOGENESIS
ALSO INTENSIFIES ACROSS EAST/SOUTHEASTERN PORTIONS OF OUR CWA.
PRECIPITATION SHOULD THEN TAPER OFF ACROSS OUR CWA STARTING AROUND
06Z AS THE PRIMARY AXIS OF MID LEVEL FRONTOGENESIS ALSO MOVES EAST
OF OUR AREA. THIS IS A SOLUTION SUPPORTED BY QPF FIELDS FROM THE
NAM...OPERATIONAL GFS...EC...SREF-MEAN...RAP...HRRR...AND 4KM WRF-
NMM. EXACT LIQUID PRECIPITATION AMOUNTS VARY FROM MODEL TO
MODEL...BUT IN GENERAL THEY AVERAGE BETWEEN 0.1" AND 0.2" ACROSS
OUR SOUTHEAST. WITH LOWER TROPOSPHERIC TEMPERATURE EXPECTED TO
AVERAGE IN THE UPPER 20S TO NEAR 30 DEGREES F...WILL GO AHEAD AND
ASSUME AN AVERAGE SNOW-WATER RATIO OF 12:1...WHICH PRESENTS
SNOWFALL ACCUMULATION GENERALLY IN THE 1-2.5" RANGE. GIVEN THE
POTENTIAL FOR MODEST SLANT-WISE CONVECTION HOWEVER...WILL GO AHEAD
AND ADD ANOTHER INCH TO THE MODEL OUTPUT WHICH PROVIDES SNOWFALL
ACCUMULATION CLOSER TO THE 2-4" RANGE.

PREV DISCUSSION... /ISSUED 358 PM CST TUE JAN 29 2013/

SHORT TERM...TONIGHT AND WEDNESDAY.

LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY. MAIN FORECAST CONCERN
IN THE EXTENDED WILL BE THE TEMPERATURES.

.GID WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL 6 AM CST WEDNESDAY FOR NEZ049-063-
064-076-077-085>087.

KS...WINTER WEATHER ADVISORY UNTIL 6 AM CST WEDNESDAY FOR KSZ006-007-
018-019.

AREA FORECAST DISCUSSION

NWS HASTINGS NE

1045 PM CST TUE JAN 29 2013

.UPDATE...RADAR RETURNS FROM KUEX THROUGH THE PAST HOUR OR SO
INDICATE BANDED PRECIPITATION CONTINUING OVER THE SOUTHEASTERN
ONE-THIRD OF THE CWA. ADVISORY WAS RIGHT ON FOR THE MOST
PART...EXCEPT INCREASED SNOWFALL RATES WERE ALSO BEING INDICATED
OVER NORTH CENTRAL KANSAS AND AS A RESULT...OPTED TO EXTEND THE
ADVISORY TO ALSO INCLUDE MITCHELL...OSBORNE...AND SMITH COUNTIES
IN KANSAS...AS WELL AS WEBSTER COUNTY IN NEBRASKA. ALSO...ALTHOUGH
IT APPEARS THE HEAVIEST SNOWFALL SHOULD BE COMING TO AN END AROUND
01Z...THE ENDING TIME APPEARED A LITTLE TOO CLOSE FOR COMFORT WITH
RESPECT WITH THE HEADLINE. IN ADDITION...AN INCREASING NORTH WIND
IS ALSO EXPECTED TO PROMOTE RESTRICTED VISIBILITY IN BLOWING SNOW
THROUGH SUNRISE WEDNESDAY. GIVEN ALL THIS...WENT AHEAD AND ALSO
EXTENDED THE ADVISORY TO 12Z.

.PREV DISCUSSION... /ISSUED 728 PM CST TUE JAN 29 2013/

PREV DISCUSSION... /ISSUED 533 PM CST TUE JAN 29 2013/

PREV DISCUSSION... /ISSUED 358 PM CST TUE JAN 29 2013/

SHORT TERM...TONIGHT AND WEDNESDAY.

LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY. MAIN FORECAST CONCERN
IN THE EXTENDED WILL BE THE TEMPERATURES.

.GID WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL 6 AM CST WEDNESDAY FOR NEZ049-063-
064-076-077-085>087.

KS...WINTER WEATHER ADVISORY UNTIL 6 AM CST WEDNESDAY FOR KSZ006-007-
018-019.

1045 PM UPDATE/0728 PM UPDATE/AVIATION...BRYANT
SHORT TERM...HEINLEIN
LONG TERM...EWALD

AREA FORECAST DISCUSSION

NWS WILMINGTON OH

109 AM EST WED JAN 30 2013

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
MODELS KEEP OFFERING SUBTLE TIMING ISSUES FOR THE ARRIVAL OF A
PREFRONTAL TROUGH LATE TONIGHT INTO WEDNESDAY MORNING THAT WILL
MOSTLY LIKELY BE REALIZED AS A WELL DEFINED BAND OF SHOWERS AND
EMBEDDED THUNDERSTORMS. DID NOT WANT TO MESS WITH THE TIMING TOO
MUCH UNTIL WE CAN GET A MORE DEFINED TRACK TO OUR WEST AND WITH A
CHANCE TO LOOK AT THE FULL SUITE OF MODELS BOTH HIGH
RES/CONVECTIVE ALLOWING AND LOWER RES/CONVECTIVE PARAMETRIZATION.

.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/...
BEHIND THE LEADING EDGE OF THIS CONVECTIVE COMPLEX WILL BE AN AREA
OF MORE STRATIFORM PRECIPITATION AND LIGHTER WINDS THAT WILL LAST
INTO THE MID MORNING HOURS IN THE WEST...AND THE EARLY AFTERNOON
IN THE EAST. ALL THIS ACTIVITY WILL BE PRE-FRONTAL...THEREFORE A
MARKED TEMPERATURE DECREASE WILL NOT BE EXPECTED UNTIL LATER IN
THE AFTERNOON AS THE FRONT PASSES. SOME SHOWER ACTIVITY IS
EXPECTED AS THE FRONT PASSES WITH A WIND SHIFT OUT THE NORTHWEST.
WINDS WILL BECOME GUSTY FROM THE AFTERNOON INTO THE LATE EVENING
BEHIND THE FRONT. WITH THE LOW RAPIDLY DEPARTING...DO NOT EXPECT
WINDS TO GUST MUCH OVER 40 MPH BEHIND THE FRONT. CAA SNOW SHOWERS
WILL BE POSSIBLE DURING THE EVENING BEHIND THE FRONT...BEFORE THE
ORIENTATION OF THE FLOW BECOMES MORE WESTERLY...ENDING ANY SNOW
SHOWERS LATE WEDNESDAY NIGHT.

TEMPERATURES WILL GRADUALLY MODERATE OVER THE NEXT FEW DAYS...AS
SURFACE HIGH PRESSURE BUILDS IN BEHIND THE SATURDAY SYSTEM. THE
TEMPERATURE FORECAST HAS BEEN INCREASED SLIGHTLY THROUGH MONDAY.

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
DYNAMIC WX SYSTEM WILL AFFECT THE REGION TODAY. LINE OF CONVECTION
ASSOCIATED WITH A PRE FRONTAL TROF IS OVER WRN INDIANA ATTM. HAVE
THIS TIMED TO THE WRN TAFS AROUND 10Z. CIGS AND VSBYS WILL DROP TO
AT LEAST MVFR WITH THE LINE. LIGHTNING WITH THE LINE HAS BEEN
WAINING OVER THE LAST COUPLE OF HOURS...SO CONTINUED WITH ONLY A
VCTS ATTM. WINDS ALOFT WITH THIS SYSTEM ARE OVER 50 KTS. QUESTION
IS WHETHER THESE WINDS WILL BE REALIZED AT THE TAF SITES. DECIDED
TO GO WITH GUSTS TO 40 KTS ATTM. HAVE THE CONVECTION TIMED E OF
CMH BY 13-15Z.

DIRECTLY BEHIND THE CONVECTION...WINDS SHOULD TURN TO THE NW
ALONG WITH MVFR CIGS AND VSBYS IN LINGERING SHRA FOR A FEW HOURS.
WINDS WILL GRADUALLY TURN BACK TO THE NW AHEAD OF THE MAIN CDFNT
BY LATE MORNING IN THE W AND EARLY AFTN IN THE E.

STRONG CDFNT REACHES THE WRN TAFS AROUND 00Z. THE CAA BEHIND THE
FNT WILL PULL DOWN STRONG AIR ALOFT. EXPECT GUSTS AGAIN OVER 35
KTS POST FRONTAL. ALONG WITH THE STRONG WINDS CIGS WILL DROP BACK
TO MVFR AND THERE WILL BE A CHANCE OF SHRA.

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

$$
SYNOPSIS...HICKMAN/LATTO
NEAR TERM...HICKMAN/LATTO
SHORT TERM...LATTO
LONG TERM...HATZOS
AVIATION...SITES

AREA FORECAST DISCUSSION

NWS NASHVILLE TN

1150 PM CST TUE JAN 29 2013

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

.AVIATION...06Z AVIATION DISCUSSION.
STILL GENERALLY BELIEVE THAT MAIN IMPACTS FROM A LINE OF STORMS MOVING
THRU WRN TN AT THIS TIME WILL BEGIN IMPACTING CKV AROUND 30/07Z...BNA
30/08Z...AND CSV 30/11Z. SOME BRIEF HEAVY RAINFALL POTENTIAL WILL ALSO
ACCOMPANY THE STRONGER STORMS...WITH SFC GUSTS TO 45KTS POSSIBLE IF NOT
HIGHER...WITH ISO SVR TSTMS CERTAINLY NOT OUT OF THE QUESTION. STILL
TIMING AND DURATION UNCERTAINTIES ABOUND...HOWEVER CKV/BNA CAN EXPECT
THE STRONGEST STORMS TO MOVE OUT OF VCNTY 30/11-30/12Z. CSV MAY CONTINUE
TO EXPERIENCE STRONGEST STORMS UNTIL AROUND 30/15Z. WINDS ARE STILL EXPECTED
TO REMAIN AROUND 20 KTS WITH GUSTS TO 30 KTS FOR AREA THRU 30/24Z. CHANGE
OVER TO ALL SHWRS IS EXPECTED W TO E DURING 30/18Z-31/00Z TOO. SOME WRAP
AROUND MOISTURE POSSIBLE...ALONG WITH WEAK INSTABILITY ASSOCIATED WITH
UPPER LEVEL TROUGH PASSAGE...TO SUPPORT A RAIN/SNOW MIX CSV FROM 31/02Z-31/06Z.
&&

.PREV DISCUSSION.../ISSUED 839 PM CST TUE JAN 29 2013/

UPDATE...
VWP CONTINUING TO SHOW A GRADUAL INCREASE IN
WIND SPEEDS...PARTICULARLY SEVERAL THOUSAND FEET ABOVE GROUND.
MODELS STILL INDICATING SOME LOWER LEVEL SUBSIDENCE OUT AHEAD OF
THE CONVECTION TO OUR WEST. LATEST TN STATE ROUNDUP SHOWING SOME
30 TO 35 MPH GUSTS ACROSS WESTERN TN. THESE HIGHER SPEEDS WILL
CONTINUE TO MOVE OUR WAY OVERNIGHT.

PREV DISCUSSION... /ISSUED 614 PM CST TUE JAN 29 2013/

UPDATE...00Z AVIATION DISCUSSION.

PREV DISCUSSION.../ISSUED 536 PM CST TUE JAN 29 2013/

PREV DISCUSSION... /ISSUED 349 PM CST TUE JAN 29 2013/

DISCUSSION...

THE FRONTAL PASSAGE AND ASSOCIATED SQUALL LINE WILL BE THE FOCUS OF
THE FORECAST.

.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 9 PM CST WEDNESDAY FOR TNZ011-032>034-065-
066-078>080.

WIND ADVISORY UNTIL 6 PM CST WEDNESDAY FOR TNZ005>010-022>031-
056>064-075-077-093>095.

$$
31

AREA FORECAST DISCUSSION

NWS BLACKSBURG VA

1146 PM EST TUE JAN 29 2013

.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 955 PM EST TUESDAY...

AS OF 300 PM EST TUESDAY...

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
AS OF 345 PM EST TUESDAY...

.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 305 PM EST TUESDAY...

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 1135 PM EST TUESDAY...

CEILINGS WILL LOWER FROM SOUTHWEST TO NORTHEAST OVERNIGHT.
EXPECTING MVFR CEILINGS AT ROA/LYH AND DAN BY 12Z. LIGHT RAIN
ALONG THE BLUE RIDGE AND IN THE FOOTHILLS MAY OCCASIONALLY REDUCE
THE VISIBILITY AT LOCAL AIRPORTS BEFORE 15Z.

AN INTENSE COLD FRONT REACHES THE FORECAST AREA BY WEDNESDAY
AFTERNOON. WINDS AHEAD OF THIS FRONT JUST ABOVE THE SURFACE WILL
BE INCREASING ABOVE 50 KNOTS WHICH IS REFLECTED IN THE LLWS PART
OF THE TAFS. BY AFTERNOON HIGH CONFIDENCE THERE WILL BE ENOUGH
MIXING TO BRING WIND GUSTS DOWN TO THE SURFACE OF 30 TO 40 KNOTS.

THE FRONT WILL PRODUCE A BROAD BAND OF SHOWERS AND POSSIBLY
ISOLATED THUNDERSTORMS WITH HEAVY RAIN AND MVFR VISIBILITIES.
MODELS AND BUFKIT SHOWED A SHARP WIND SHIFT TO THE WEST WITH THE
FRONTAL PASSAGE. WINDS WILL STILL BE GUSTY BEHIND THE FRONT
WEDNESDAY NIGHT.

AS MUCH COLDER AIR ARRIVES BY THURSDAY...UPSLOPE SNOW SHOWERS
WILL DEVELOP FOR KBLF AND KLWB...WITH CLEARING EAST OF THE BLUE
RIDGE. NORTHWEST FLOW WILL PREVAIL FRIDAY THROUGH SUNDAY WITH
POTENTIAL FOR TWO CLIPPER SYSTEMS TO BRING SNOW TO THE
MOUNTAINS...ONE LATE THURSDAY NIGHT INTO FRIDAY AND THE NEXT
SATURDAY INTO SUNDAY.

$$
SYNOPSIS...AMS/RAB
NEAR TERM...AMS/DS
SHORT TERM...PM
LONG TERM...KK
AVIATION...AMS/KK
HYDROLOGY...

AREA FORECAST DISCUSSION

NWS LA CROSSE WI

303 AM CST WED JAN 30 2013

.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT
303 AM CST TUE JAN 29 2013

303 AM UPDATE...30.00Z NAM...HIRES ARW...HIRES NMM AND 30.05Z HRRR
ALL HAVE A GOOD HANDLE ON THE DEFORMATION AREA OF SNOW APPROACHING
FROM IOWA. THE SNOW LOOKS TO SPREAD ACROSS MOST OF THE AREA EXCEPT
FOR TAYLOR COUNTY BY 6 AM. IN ADDITION...THE MODELS FORECAST THAT
THE OVERALL AREA OF SNOW HAS SHIFTED SLIGHTLY TO THE EAST. THIS
REQUIRES SOME ADJUSTMENTS TO THE HAZARDS...DOWNGRADING SOME OF THE
WARNINGS TO ADVISORIES AND REMOVING THE PREVIOUS ADVISORIES. PART
OF THE PROBLEM TOO WITH REACHING THE WARNING CRITERIA IS THAT SNOW
HAS REALLY HELD OFF MUCH OF THE CURRENT NIGHT TIME PERIOD THUS
FAR...DUE TO DRY AIR IN PLACE SEEN ON THE 00Z MPX SOUNDING. IN
ADDITION...THE FORCING WITH THE COMMA HEAD OF THE
SHORTWAVE...CURRENTLY COMING UP THROUGH NORTHWEST MISSOURI...HAS
TAKEN TIME TO REACH THE AREA. WATCH WARNING ADVISORY SEGMENT BELOW
DENOTES THE ADJUSTMENTS TO THE HAZARDS. MORE INFORMATION ABOUT THE
CURRENT SNOW EVENT WILL BE FORTHCOMING IN THE HOUR WITH THE
REGULAR 4 AM ISSUANCE.

PREVIOUS DISCUSSION ISSUED AT 303 PM CST TUE JAN 29

MAIN FORECAST FOCUS IS ON WINTER STORM TONIGHT AND WEDNESDAY WITH
POTENTIAL MIXED PRECIPITATION AT ONSET AND THEN SNOW AMOUNTS AND
BLOWING SNOW. ALSO WIND CHILL FOR WEDNESDAY NIGHT INTO THURSDAY
MORNING.

18Z SURFACE ANALYSIS SHOWS COLD FRONT NOW PUSHING THROUGH SOUTHWEST
WISCONSIN. TEMPERATURES AHEAD OF THE FRONT WERE IN THE MIDDLE 40S IN
GRANT COUNTY AND THE UPPER 50S IN EXTREME NORTHERN ILLINOIS.
MEANWHILE...BEHIND THE FRONT TEMPERATURES GAVE FALLEN INTO THE
MIDDLE 30S. AREA RADAR SHOWING ANOTHER SURGE OF RAIN LIFTING
NORTHWARD THROUGH EASTERN IOWA.

29.12Z DETERMINISTIC MODELS STILL SHOWING SOME DIFFERENCES. GFS/GEM
AND THE 29.00Z ECMWF ALL SHOWING DEFORMATION BAND OF PRECIPITATION
ACROSS THE FORECAST AREA...WHILE NAM APPEARS TO BE THE OUTLIER AND
HAS SHIFTED THE BULK OF THE PRECIPITATION FURTHER SOUTH AND EAST.
HAVE SIDED WITH THE MORE CONSISTENT NON NAM SOLUTIONS.

FOR TONIGHT...COLD AIR SURGES INTO THE AREA BEHIND THE COLD
FRONT...WHILE MOISTURE LIFTS NORTHWARD. THERMAL PROFILES SUGGEST
MAINLY RAIN FOR SOUTHWEST WISCONSIN WITH A SWITCH OVER TO SNOW
TOWARDS MIDNIGHT. THERE COULD BE A BRIEF PERIOD OF SLEET MIXED IN
BEFORE THE CHANGE OVER OCCURS. WITH THE ALREADY SWOLLEN RIVERS FROM
THE EARLIER RAINS AND ADDING ANOTHER .30 INCHES THIS EVENING WILL
LIKELY SEE THE HYDRO PROBLEM CONTINUING AND WILL CONTINUE THE FLOOD
WATCH FOR GRANT COUNTY. THE REMAINDER OF THE AREA WILL SEE ALL SNOW
WITH THE ACCUMULATING SNOW BEGINNING AFTER 06Z.

THE SNOW CONTINUES WEDNESDAY AS ANOTHER SHORTWAVE/SURFACE LOW LIFTS
NORTHEAST ACROSS EASTERN IOWA INTO NORTHERN ILLINOIS. DEFORMATION
BAND OF HEAVY SNOW WILL SET UP ACROSS THE SOUTHEAST HALF OF THE
FORECAST AREA. SOUNDINGS SHOWING STRONG LIFT IN THE DENDRITIC GROWTH
ZONE DURING THE MORNING HOURS. EXPECT SNOW RATIOS IN THE 15:1 TO
18:1 RANGE WHICH SHOULD RESULT INA BAND OF 6 TO 9 INCHES OF
SNOW...WITH THE HIGHER AMOUNTS RUNNING FROM AROUND THE
ADAMS/FRIENDSHIP TO CLAYTON COUNTY IOWA LINE. HAVE UPGRADED THE
WATCH AREA TO WARNING...WITH A BORDERING WINTER WEATHER ADVISORY
NORTH OF THE WARNING AREA. IN ADDITION...PRESSURE GRADIENT TIGHTENS
AND WINDS LOOK TO GUST TO 20 TO 30 MPH WHICH WILL CREATE SOME
BLOWING SNOW...ESPECIALLY ACROSS THE MORE OPEN AREAS. SNOW WILL
TAPER OFF BY MID TO LATE AFTERNOON...BUT WIT THE WINDS CONTINUING
WILL SEE TE BLOWING AND DRIFTING OF THE SNOW.

ARCTIC AIR WILL CONTINUE TO SURGE INTO THE AREA WEDNESDAY NIGHT.
PRESSURE GRADIENT REMAIN RATHER TIGHT AND WITH TEMPERATURES FALLING
INTO THE SINGLE DIGITS ABOVE AND BELOW ZERO WILL SEE WIND CHILLS
APPROACHING 20 BELOW OVER SOUTHEAST MINNESOTA AND NORTHEAST IOWA.

ARCTIC HIGH THEN BUILDS SOUTHWARD THROUGH THE NORTHERN PLAINS
THURSDAY. 850MB TEMPERATURES BOTTOM OUT IN THE 20 TO 25 BELOW ZERO
RANGE CELSIUS AND WITH THE HIGH STILL OVER THE NORTHERN
PLAINS...WINDS WILL CONTINUE TO BE A FACTOR. VERY LITTLE REBOUND
EXPECTED IN THE AMBIENT TEMPERATURE WIND CHILLS WILL REMAIN IN THE
10 TO 20 BELOW ZERO RANGE. AS THE HIGH SLIPS SOUTH THE RIDGE AXIS
DOES SHIFT ACROSS THE FORECAST AREA THURSDAY NIGHT. IF THIS OCCURS
WILL LIKELY SEE SOMEWHAT LIGHTER WINDS AND GOOD RADIATIONAL COLLING
CONDITIONS. ALONG WITH THIS A LIKELY FRESH SNOWPACK COULD SEE
TEMPERATURES REALLY BOTTOM OUT IN THE TEENS BELOW ZERO. DID LOWER A
FEW DEGREES FROM THE PREVIOUS FORECAST...BUT MAY NEED TO BE LOWERED
MORE. GIVEN WINDS NOT GOING CALM WILL LIKELY NEED WIND CHILL
ADVISORIES FOR MUCH OF THE AREA.

.LONG TERM...
303 PM CST TUE JAN 29 2013

NORTHWEST FLOW CONTINUES ACROSS THE REGION THROUGH THE
WEEKEND...WITH A SURFACE HIGH DRIFTING ACROSS THE AREA. ANOTHER
SHORTWAVE LOOKS TO DROP THROUGH THE FLOW LATE SUNDAY NIGHT AND
MONDAY AND COULD BRING SOME SNOW TO THE AREA. ECMWF FURTHER NORTH
AFFECTING MAINLY NORTHERN AND EASTERN WISCONSIN. FOR NOW KEPT THE
LOWER END PROBABILITIES ACROSS THE FAR NORTH. OTHERWISE...TEMPERATURES
MODERATE SOMEWHAT AHEAD OF THIS SYSTEM TO SLIGHTLY ABOVE
NORMAL...BUT THEN FALL BACK TO NEAR NORMAL ON TUESDAY.

.AVIATION...THROUGH 06Z THURSDAY
1105 PM CST TUE JAN 29 2013

THE SURFACE LOW HAS MOVED SLOWLY OUT OF NORTHWEST ARKANSAS INTO
SOUTH CENTRAL MISSOURI THIS EVENING. THIS HAS RESULTED IN A SLOW
NORTHWARD PUSH OF THE SNOW FROM SOUTHWEST IOWA INTO CENTRAL IOWA.
THE 30.00Z NAM AND 30.02Z HRRR CONTINUE TO HAVE A GOOD HANDLE ON
HOW THE PRECIPITATION HAS BEEN EVOLVING THIS EVENING WITH BOTH
MODELS SUGGESTING THAT KLSE HAS A BETTER CHANCE OF GETTING INTO
THE PRECIPITATION THAN KRST DOES. WITH THE NORTHEAST MOVEMENT OF
THE SNOW...IT IS EXPECTED TO START MOVING INTO KLSE LATE TONIGHT
AND KRST AROUND 12Z WITH VISIBILITIES GOING DOWN TO MVFR. AS THE
MODERATE TO STRONG FRONTOGENESIS IN THE 750-500 MB LAYER COMES
ACROSS WEDNESDAY MORNING...THE SNOW SHOULD INTENSIFY BUT WITH THE
BEST ISENTROPIC UP GLIDE ON THE 290K SURFACE REMAINING SOUTHEAST
OF BOTH TAF SITES...NOT EXPECTING THE HEAVIEST BAND OF SNOW TO
IMPACT EITHER TAF SITE. BOTH SITES SHOULD STILL SEE IFR CONDITIONS
BUT THE VISIBILITY SHOULD BE LOWER AT KLSE. KRST WILL SEE IMPROVEMENT
STARTING ALREADY LATE WEDNESDAY MORNING AND IN THE EARLY AFTERNOON
OR KLSE AS CONDITIONS GO BACK TO MVFR. SOME FLURRIES EXPECTED TO
HANG ON DURING THE AFTERNOON WITH VFR VISIBILITY BUT LOOK FOR THE
CEILINGS TO REMAIN MVFR FOR THE REMAINDER OF THE PERIOD. THE TIGHT
GRADIENT AROUND THE SURFACE LOW WILL PRODUCE SUSTAINED NORTH TO
NORTHWEST WINDS OF 15 TO 20 KNOTS WITH GUSTS OF 25 TO 30. THE NAM
BUFKIT SOUNDINGS SUGGEST THE LOW LEVEL LAPSE RATES WILL REMAIN
STEEP ENOUGH TO KEEP THE GUSTS GOING AFTER SUNSET WEDNESDAY EVENING.

.ARX WATCHES/WARNINGS/ADVISORIES...
303 AM CST WED JAN 30 2013

WI...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ029-
033-034-041.

WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR WIZ042>044-
053>055-061.

MN...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ088-
095-096.

WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST THURSDAY
FOR MNZ079-086-087-094-095.

IA...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR IAZ009-
010-018-019.

WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST THURSDAY
FOR IAZ008-009-018-019.

WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR IAZ011-029-
030.

SHORT TERM...RABERDING/AJ
LONG TERM...RABERDING
AVIATION...04

AREA FORECAST DISCUSSION

NWS LA CROSSE WI

1105 PM CST TUE JAN 29 2013

.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT
303 PM CST TUE JAN 29 2013

.LONG TERM...
303 PM CST TUE JAN 29 2013

.AVIATION...THROUGH 06Z THURSDAY
1105 PM CST TUE JAN 29 2013

.ARX WATCHES/WARNINGS/ADVISORIES...
640 PM CST TUE JAN 29 2013

WI...WINTER STORM WARNING UNTIL 6 PM CST WEDNESDAY FOR WIZ033-034-041-
042-053.

WINTER WEATHER ADVISORY UNTIL 6 PM CST WEDNESDAY FOR WIZ017-029-
032.

WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 PM CST WEDNESDAY
FOR WIZ043-044-054-055-061.

MN...WINTER STORM WARNING UNTIL 6 PM CST WEDNESDAY FOR MNZ088-095-096.

WINTER WEATHER ADVISORY UNTIL 6 PM CST WEDNESDAY FOR MNZ079-086-
087-094.

IA...WINTER STORM WARNING UNTIL 6 PM CST WEDNESDAY FOR IAZ009>011-018-
019-029.

WINTER WEATHER ADVISORY UNTIL 6 PM CST WEDNESDAY FOR IAZ008.

WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 PM CST WEDNESDAY
FOR IAZ030.

SHORT TERM...RABERDING
LONG TERM...RABERDING
AVIATION...04

AREA FORECAST DISCUSSION...UPDATED

NWS PEACHTREE CITY GA

647 AM EST WED JAN 30 2013

.PREV DISCUSSION... /ISSUED 621 AM EST WED JAN 30 2013/

UPDATE...
SECOND UPDATE TO INCLUDE EXPANDED TORNADO WATCH 17 AREA IN THE
FFC WATCHES/WARNINGS/ADVISORIES SECTION BELOW.

BELANGER

PREV DISCUSSION... /ISSUED 410 AM EST WED JAN 30 2013/

SHORT TERM /TODAY THROUGH THURSDAY NIGHT/...
PRIMARY CONCERN IS THREAT AND TIMING OF SEVERE CONVECTION THIS
AFTERNOON AND EARLY EVENING. VERY IMPRESSIVE STORM SYSTEM
APPROACHING THE STATE THIS MORNING. WHILE FAVORABLE SIG TOR
PARAMETER VALUES CURRENTLY CONFINED TO AREA CLOSER TO THE COAST
BASED ON RAP ANALYSES...HAVE SEEN A FEW REPORTS OF WIND DAMAGE
FURTHER NORTH OVER WRN TN AND NRN MS IN LOW CAPE AREAS. IF MODELS
ARE TO BE BELIEVED...PARAMETERS SHOULD BE MORE FAVORABLE HERE THAN
WHAT IS CURRENTLY SHOWN TO THE WEST. 00Z MODELS HAVE SLOWED TIMING
OF MAIN LINE OF TSRA SOMEWHAT WITH NAM SLOWEST. 06Z NAM ALSO
CONTINUING SLOWER TREND. LINE SHOULD MOVE INTO NW CORNER OF CWA
AROUND 10AM... I-85 BY 3PM AND AHN-MCN-AMERICUS LINE BY 7PM AND
EXITING SE CORNER OF CWA AROUND 10PM. INGREDIENTS STILL APPEAR
SUFFICIENT FOR AT LEAST ISOLD AREAS OF WIND DMG OR BRIEF TORNADOES.
AS OFTEN THE CASE...06Z NAM MLCAPE SHOWING MORE INSTABILITY THAN
OTHER MODELS WITH VALUES AROUND 400-700 J/KG. 00Z GFS HAS 200-400
J/KG OVER ALL BUT NE GA. VERTICAL WIND SHEAR WILL BE VERY STRONG.
0-1KM BULK SHEAR 40-50KTS SEEN ON GFS AND NAM. FAVORABLE CIN...LCL
AND DEEP LAYER SHEAR YIELDING DECENT SIG TOR PARAMETER VALUES...
1-2 WITH GFS AND 2-5 ON NAM. THIS VALUES ARE HIGHER THAN PREV SVR
EVENT ON DEC 26 WHEN WE SAW 3 WEAK TORNADOES IN MIDDLE GA.

SNELSON

LONG TERM /FRIDAY THROUGH TUESDAY/...
EXTENDED MODELS IN FAIRLY GOOD AGREEMENT THROUGH THE LONG
TERM...WITH LONG WAVE UPPER-LEVEL TROUGH SITUATED OVER THE EASTERN
U.S. THOUGH EARLY NEXT WEEK. GENERALLY...NORTHWEST FLOW WILL
PERSIST OVER THE REGION...AND MODELS CONTINUE TO ADVERTISE A
SERIES OF UPPER LEVEL SHORT WAVES IMPACTING THE AREA AS A RESULT.
THE FIRST DISTURBANCE OCCURS AT THE TAIL END OF THE SHORT TERM
PERIODS...AND WHAT MOISTURE QUICKLY DISSIPATES INTO THE LONG TERM
EARLY FRIDAY.

BELANGER

FIRE WEATHER...
AS DRY AIR PLUNGES IN BEHIND FRONT...HUMIDITY PROGGED TO DROP TO 22
TO 25 PCT FOR A FEW HOURS THURS AFTERNOON OVER MIDDLE GA. WITH 1 TO
2 INCHES OF RAIN EXPECTED TODAY...FUELS ARE EXPECTED TO BE TOO WET
TO REQUIRE ANY FIRE DANGER STATEMENTS.

SNELSON

.AVIATION...
12Z UPDATE...
STILL MONITORING LINE OF STRONG TSRA THAT WILL MOVE ACROSS THE
STATE TODAY AND THIS EVENING. TIMING HAS SHIFTED SLIGHTLY AND NOW
APPEARS TSRA WILL AFFECT ATL METRO 19Z-23Z. EXPECT STRONG
CROSSWIND AT E-W RUNWAY AIRPORTS TODAY...GUSTS COULD APPROACH
32KTS AT KATL. CIGS SHOULD STAY RIGHT NEAR IFR THRESHOLD AT KATL
AND REMAIN JUST ABOVE IFR ELSEWHERE. EXPECT END TO CIGS AND PRECIP
AROUND 23-00Z. STRONG WEST WINDS WILL CONTINUE OVERNIGHT AND
THURS.

//ATL CONFIDENCE...12Z UPDATE...
MEDIUM CONFIDENCE ON IFR CIGS THIS MORNING.
HIGH CONFIDENCE ON ALL OTHER ELEMENTS.

SNELSON

HIGH WIND WARNING UNTIL 6 PM EST THIS EVENING FOR THE FOLLOWING
ZONES: DAWSON...FANNIN...GILMER...LUMPKIN...MURRAY...PICKENS...
TOWNS...UNION...WHITE.

FLOOD WATCH THROUGH THIS EVENING FOR THE FOLLOWING ZONES:
BARTOW...CATOOSA...CHATTOOGA...CHEROKEE...COBB...DADE...DAWSON...
FANNIN...FLOYD...FORSYTH...GILMER...GORDON...HARALSON...
LUMPKIN...MURRAY...NORTH FULTON...PAULDING...PICKENS...POLK...
TOWNS...UNION...WALKER...WHITE...WHITFIELD.

WIND ADVISORY FROM 6 PM THIS EVENING TO MIDNIGHT EST TONIGHT FOR
THE FOLLOWING ZONES: DAWSON...FANNIN...GILMER...LUMPKIN...
MURRAY...PICKENS...TOWNS...UNION...WHITE.

TORNADO WATCH UNTIL 1 PM EST THIS AFTERNOON FOR THE FOLLOWING
ZONES: BARTOW...CARROLL...CATOOSA...CHATTOOGA...DADE...FLOYD...
GORDON...HARALSON...HEARD...MURRAY...PAULDING...POLK...WALKER...
WHITFIELD.

SHORT TERM...SNELSON
LONG TERM....31
AVIATION...SNELSON

AREA FORECAST DISCUSSION

NWS PEACHTREE CITY GA

621 AM EST WED JAN 30 2013

.UPDATE...
SECOND UPDATE TO INCLUDE EXPANDED TORNADO WATCH 17 AREA IN THE
FFC WATCHES/WARNINGS/ADVISORIES SECTION BELOW.

BELANGER

PREV DISCUSSION... /ISSUED 410 AM EST WED JAN 30 2013/

SHORT TERM /TODAY THROUGH THURSDAY NIGHT/...
PRIMARY CONCERN IS THREAT AND TIMING OF SEVERE CONVECTION THIS
AFTERNOON AND EARLY EVENING. VERY IMPRESSIVE STORM SYSTEM
APPROACHING THE STATE THIS MORNING. WHILE FAVORABLE SIG TOR
PARAMETER VALUES CURRENTLY CONFINED TO AREA CLOSER TO THE COAST
BASED ON RAP ANALYSES...HAVE SEEN A FEW REPORTS OF WIND DAMAGE
FURTHER NORTH OVER WRN TN AND NRN MS IN LOW CAPE AREAS. IF MODELS
ARE TO BE BELIEVED...PARAMETERS SHOULD BE MORE FAVORABLE HERE THAN
WHAT IS CURRENTLY SHOWN TO THE WEST. 00Z MODELS HAVE SLOWED TIMING
OF MAIN LINE OF TSRA SOMEWHAT WITH NAM SLOWEST. 06Z NAM ALSO
CONTINUING SLOWER TREND. LINE SHOULD MOVE INTO NW CORNER OF CWA
AROUND 10AM... I-85 BY 3PM AND AHN-MCN-AMERICUS LINE BY 7PM AND
EXITING SE CORNER OF CWA AROUND 10PM. INGREDIENTS STILL APPEAR
SUFFICIENT FOR AT LEAST ISOLD AREAS OF WIND DMG OR BRIEF TORNADOES.
AS OFTEN THE CASE...06Z NAM MLCAPE SHOWING MORE INSTABILITY THAN
OTHER MODELS WITH VALUES AROUND 400-700 J/KG. 00Z GFS HAS 200-400
J/KG OVER ALL BUT NE GA. VERTICAL WIND SHEAR WILL BE VERY STRONG.
0-1KM BULK SHEAR 40-50KTS SEEN ON GFS AND NAM. FAVORABLE CIN...LCL
AND DEEP LAYER SHEAR YIELDING DECENT SIG TOR PARAMETER
VALUES...1-2 WITH GFS AND 2-5 ON NAM. THIS VALUES ARE HIGHER THAN
PREV SVR EVENT ON DEC 26 WHEN WE SAW 3 WEAK TORNADOES IN MIDDLE
GA.

SNELSON

BELANGER

SNELSON

AVIATION...
06Z UPDATE...
MAIN CONCERN IS TIMING OF TSRA THIS AFTERNOON. WELL DEFINED LINE
OF TSRA WILL MOVE THRU FROM WEST TO EAST...IMPACTING ATL METRO
AIRPORTS AROUND 18Z-22Z. SHOULD SEE WIDESPREAD -SHRA DEVELOPING A
FEW HOURS BEFORE THEN AND POSSIBLY CONTINUING AFTER LINE OF TSRA
HAS MOVED THRU. OTHER CONCERN TODAY IS STRONG CROSSWINDS AT
AIRPORTS WITH E-W RUNWAY CONFIGURATION...INCLUDING KATL WHERE
CROSSWIND COMPONENT GUSTS 16Z-22Z COULD APPROACH 30KTS. IFR CIGS
LIKELY AT MOST AIRPORTS FROM 09Z THRU 14Z THOUGH MAY BE TOO WARM
OVER MIDDLE GA AIRPORTS FOR CIGS TO GET DOWN TO IFR. CIGS WILL
IMPROVE AFTER LINE OF TSRA MOVES THRU...AROUND 22Z AT ATL...THEN
CLEAR ENTIRELY AFTER 06Z-09Z THURS.

//ATL CONFIDENCE...06Z UPDATE...
MEDIUM CONFIDENCE ON IFR CIGS THIS MORNING AND TSRA TIMING.
HIGH CONFIDENCE ON ALL OTHER ELEMENTS.

SNELSON

HIGH WIND WARNING UNTIL 6 PM EST THIS EVENING FOR THE FOLLOWING
ZONES: DAWSON...FANNIN...GILMER...LUMPKIN...MURRAY...PICKENS...
TOWNS...UNION...WHITE.

WIND ADVISORY FROM 6 PM THIS EVENING TO MIDNIGHT EST TONIGHT FOR
THE FOLLOWING ZONES: DAWSON...FANNIN...GILMER...LUMPKIN...
MURRAY...PICKENS...TOWNS...UNION...WHITE.

SHORT TERM...SNELSON
LONG TERM....31
AVIATION...SNELSON

AREA FORECAST DISCUSSION

NWS PEACHTREE CITY GA

555 AM EST WED JAN 30 2013

.UPDATE...
UPDATE TO INCLUDE TORNADO WATCH 17 AREA IN THE FFC
WATCHES/WARNINGS/ADVISORIES SECTION BELOW.

BELANGER

.PREV DISCUSSION... /ISSUED 410 AM EST WED JAN 30 2013/

SHORT TERM /TODAY THROUGH THURSDAY NIGHT/...
PRIMARY CONCERN IS THREAT AND TIMING OF SEVERE CONVECTION THIS
AFTERNOON AND EARLY EVENING. VERY IMPRESSIVE STORM SYSTEM
APPROACHING THE STATE THIS MORNING. WHILE FAVORABLE SIG TOR
PARAMETER VALUES CURRENTLY CONFINED TO AREA CLOSER TO THE COAST
BASED ON RAP ANALYSES...HAVE SEEN A FEW REPORTS OF WIND DAMAGE
FURTHER NORTH OVER WRN TN AND NRN MS IN LOW CAPE AREAS. IF MODELS
ARE TO BE BELIEVED...PARAMETERS SHOULD BE MORE FAVORABLE HERE THAN
WHAT IS CURRENTLY SHOWN TO THE WEST. 00Z MODELS HAVE SLOWED TIMING
OF MAIN LINE OF TSRA SOMEWHAT WITH NAM SLOWEST. 06Z NAM ALSO
CONTINUING SLOWER TREND. LINE SHOULD MOVE INTO NW CORNER OF CWA
AROUND 10AM... I-85 BY 3PM AND AHN-MCN-AMERICUS LINE BY 7PM AND
EXITING SE CORNER OF CWA AROUND 10PM. INGREDIENTS STILL APPEAR
SUFFICIENT FOR AT LEAST ISOLD AREAS OF WIND DMG OR BRIEF TORNADOES.
AS OFTEN THE CASE...06Z NAM MLCAPE SHOWING MORE INSTABILITY THAN
OTHER MODELS WITH VALUES AROUND 400-700 J/KG. 00Z GFS HAS 200-400
J/KG OVER ALL BUT NE GA. VERTICAL WIND SHEAR WILL BE VERY STRONG.
0-1KM BULK SHEAR 40-50KTS SEEN ON GFS AND NAM. FAVORABLE CIN...LCL
AND DEEP LAYER SHEAR YIELDING DECENT SIG TOR PARAMETER
VALUES...1-2 WITH GFS AND 2-5 ON NAM. THIS VALUES ARE HIGHER THAN
PREV SVR EVENT ON DEC 26 WHEN WE SAW 3 WEAK TORNADOES IN MIDDLE
GA.

SNELSON

BELANGER

SNELSON

//ATL CONFIDENCE...06Z UPDATE...
MEDIUM CONFIDENCE ON IFR CIGS THIS MORNING AND TSRA TIMING.
HIGH CONFIDENCE ON ALL OTHER ELEMENTS.

SNELSON

HIGH WIND WARNING UNTIL 6 PM EST THIS EVENING FOR THE FOLLOWING
ZONES: DAWSON...FANNIN...GILMER...LUMPKIN...MURRAY...PICKENS...
TOWNS...UNION...WHITE.

WIND ADVISORY FROM 6 PM THIS EVENING TO MIDNIGHT EST TONIGHT FOR
THE FOLLOWING ZONES: DAWSON...FANNIN...GILMER...LUMPKIN...
MURRAY...PICKENS...TOWNS...UNION...WHITE.

TORNADO WATCH UNTIL 1 PM EST THIS AFTERNOON FOR THE FOLLOWING
ZONES: CATOOSA...DADE...MURRAY...WALKER...WHITFIELD.

SHORT TERM...SNELSON
LONG TERM....BELANGER
AVIATION...SNELSON

AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

952 AM EST WED JAN 30 2013

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

.SYNOPSIS...
ISSUED AT 420 AM EST WED JAN 30 2013

STRONG SYSTEM WILL BE PASSING THROUGH THE AREA THROUGH TONIGHT.
SHOWERS IN THE WAKE OF THUNDERSTORMS WILL CONTINUE THROUGH MID
MORNING...WITH ADDITIONAL SHOWERS POSSIBLY DEVELOPING LATER TODAY.
ARCTIC AIR WILL BEGIN RUSHING INTO THE AREA LATE THIS
AFTERNOON...AND ANY REMAINING PRECIPITATION WILL CHANGE QUICKLY
OVER TO SNOW THIS EVENING. ANOTHER UPPER LEVEL WAVE WILL PUSH
THROUGH THE AREA TOMORROW AFTERNOON AND EVENING...PERHAPS BRINGING
LIGHT SNOW SHOWERS TO THE AREA...FOLLOWED BY ANOTHER DISTURBANCE
WITH THE POTENTIAL FOR SNOW FRIDAY NIGHT INTO SATURDAY.

.NEAR TERM /REST OF TODAY/...

ISSUED AT 943 AM EST WED JAN 30 2013

RAIN ASSOCIATED WITH OVERNIGHT STORMS HAS MOVED OUT OF THE AREA.
RADAR MOSAIC SHOWS A LINE OF SHOWERS OVER CENTRAL ILLINOIS AND
SHORT TERM MODELS SHOW THIS LINE MOVING INTO THE WESTERN COUNTIES
AROUND 17-18Z AND ACROSS THE AREA FROM THERE. ALSO SOME POTENTIAL
FOR A FEW SHOWERS TO POP UP AHEAD OF THIS LINE AND MOVE NORTHEAST
TO THE AREA FROM SOUTHERN ILLINOIS/WESTERN KENTUCKY. HAVE ADDED
SOME DETAIL TO THE NEXT FEW HOURS COMPLETELY REMOVING RAIN FOR
MOST OF THE AREA AND THEN BRING BACK CHANCES STARTING AT 17Z AND
RAMPING UP FROM THERE. TIMING OF CHANGEOVER TO SNOW STILL LOOKS
LIKE IT COULD HAPPEN IN THE NORTHWEST AFTER 21Z BUT SHOULD NOT
REACH THE REST OF THE AREA UNTIL AFTER 0Z. WINDS THIS MORNING ARE
LIGHTER THAN FORECAST BUT SOUNDINGS STILL HAVE THEM INCREASING
QUITE A BIT THIS AFTERNOON WITH GUSTS AROUND 40 MPH EXPECTED THIS
AFTERNOON. WITH THE SLIGHTLY SLOWER ARRIVAL OF THE COLD AIR
BEHIND THE FINAL COLD FRONT /STILL OVER WESTERN ILLINOIS/ AND LESS
RAIN AROUND THE NEXT FEW HOURS EXPECT TEMPERATURES TO RISE IN THE
CENTRAL AND EASTERN COUNTIES AND REMAIN STEADY IN THE WEST UNTIL
MID AFTERNOON WHEN THEY SHOULD START TO PLUMMET IN THE WEST AND
THIS WILL OVERSPREAD THE AREA THROUGH THE EVENING.

.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
ISSUED AT 420 AM EST WED JAN 30 2013

AS THE SECOND COLD FRONT PASSES THE AREA EARLY THIS
EVENING...EXPECT THAT ALL PRECIP WILL CHANGE TO SNOW BY AROUND
02-03Z. PRECIP SHOULD BE SNOW ACROSS THE WEST BY 00Z...WITH
CHANGEOVER PROGRESSING RAPIDLY ACROSS THE AREA. MOST PRECIP SHOULD
BE DONE BY 06Z.

BRIEF LULL IN PRECIP CHANCES EXPECTED LATE TONIGHT INTO EARLY
THURSDAY. ADDITIONAL WAVE WILL PUSH THROUGH THE AREA LATE THURSDAY
INTO THURSDAY NIGHT...AND MODELS ARE A BIT MORE BULLISH ON THIS
WAVE THAN PREVIOUSLY. ADDITIONALLY...FORCING IS IMPROVED...WITH
DECENT Q VECTOR CONVERGENCE AND EVEN SOME GOOD FRONTOGENESIS AND
MODERATE EPV. WILL LEAN TO HIGHER END OF THE GUIDANCE ENVELOPE.
THIS MAY PRODUCE LIGHT ACCUMULATIONS OF AN INCH OR LESS ACROSS
PORTIONS OF THE AREA.

FINALLY...ADDITIONAL WAVE WILL APPROACH ON FRIDAY NIGHT...LOW
CHANCE POPS APPEAR REASONABLE.

WINDS TONIGHT POST FRONT MAY GUST TO AROUND 30-35KT AT TIMES...AS
ACCORDING TO BUFKIT SOUNDINGS AND LOW LEVEL WIND PROGS OFF MODELS.
AGAIN THIS IS BELOW ADVISORY CRITERIA.

ON TEMPS...CONSENSUS APPEARED REASONABLE AND ONLY A FEW MINOR
TWEAKS REQUIRED. DID BUMP TEMPS DOWN SLIGHTLY THROUGHOUT WITH COLD
ADVECTION ONGOING UNTIL LATE IN THE PERIOD.

.LONG TERM /SATURDAY THROUGH TUESDAY/...
ISSUED AT 305 AM EST WED JAN 30 2013

AS FAR AS TEMPERATURES ARE CONCERNED MODELS HAVE TRENDED A LITTLE
COLDER OVER THE WEEKEND AND TUESDAY. IN MOST CASES WENT WITH A
BLEND OF ALL BLEND AND CONSALL NUMBERS.

.AVIATION /DISCUSSION FOR THE 301500Z TAF ISSUANCE/...
ISSUED AT 940 AM EST TUE JAN 29 2013

WIDESPREAD RAIN HAS MOVED EAST OF THE TERMINALS THIS MORNING WITH
IFR AND LOWER CONDITIONS PERSISTING ACROSS THE REGION. MADE
ADJUSTMENTS TO WIND SPEED/DIRECTION BASED ON CURRENT OBS. ALSO AM
LESS OPTIMISTIC IN CEILING IMPROVEMENT THROUGH EARLY AFTERNOON WITH
CEILINGS BELOW 1000FT EXTENDING BACK INTO EASTERN ILLINOIS. MOST
RECENT HRRR GUIDANCE AND OBS AGREE ON SCATTERED SHOWERS EXPANDING
BACK INTO THE REGION BY EARLY AFTERNOON AS THE COLD FRONT
APPROACHES. WIND GUSTS WILL INCREASE THROUGH THE AFTERNOON ALONG AND
BEHIND THE FRONTAL PASSAGE.

12Z DISCUSSION FOLLOWS.

MOSTLY MVFR CEILINGS THROUGH THE PERIOD WITH GUSTY WINDS THIS
AFTERNOON AND TONIGHT.

LOW PRESSURE OVER NORTHEAST ILLINOIS WILL TRACK NORTHEAST ACROSS THE
GREAT LAKES AS A COLD FRONT MOVES ACROSS CENTRAL INDIANA LATER
TODAY. AREA OF RAIN CURRENTLY ACROSS CENTRAL INDIANA WILL MOVE ON
TO THE EAST. HOWEVER RAPID REFRESH AND OTHER MODELS INDICATE
SCATTERED SHOWERS MOVING BACK IN ACROSS TAF SITES BY MIDDAY AND WITH
PRECIPITATION CHANGING TO LIGHT SNOW SHOWERS OR FLURRIES BY
EVENING.

WITH THE EXCEPTION OF KLAF CEILINGS CURRENTLY AT OR ABOVE 3
THOUSAND. BUT UPSTREAM THEY ARE MUCH LOWER AND THESE LOWER CEILINGS
WILL SPREAD ACROSS TAF SITES LATER TODAY. AT TIME BELIEVE CEILINGS
SHOULD AVERAGE ABOUT 15 HUNDRED FEET BY THIS AFTERNOON AND EARLY
TONIGHT WITH SOME IMPROVEMENT LATE TONIGHT.

WINDS HAVE TEMPORARILY BECOME LIGHT THIS MORNING BUT WILL PICK UP
AGAIN BY THIS AFTERNOON AFTER COLD FRONT MOVES THROUGH AND WITH SOME
AREAS GUSTING UP TO 30 KNOTS LATE TODAY AND TONIGHT..

.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SYNOPSIS...NIELD
NEAR TERM...CP
SHORT TERM...NIELD
LONG TERM....JH
AVIATION...JH/RYAN

AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

942 AM EST WED JAN 30 2013

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

.SYNOPSIS...
ISSUED AT 420 AM EST WED JAN 30 2013

.NEAR TERM /TODAY/...
ISSUED AT 420 AM EST WED JAN 30 2013

STORMS ARE EXITING THE FORECAST AREA AT THIS TIME...WITH ONLY
STRATIFORM RAIN IN THE WAKE OF THE STORMS ACROSS THE AREA. EXPECT
A LULL PERHAPS LATER THIS MORNING WITH THE POTENTIAL FOR
ADDITIONAL SHOWERS LATER THIS AFTERNOON AS THE UPPER WAVE
APPROACHES. SECONDARY COLD FRONT WILL PASS STARTING LATE THIS
AFTERNOON/EARLY EVENING.

BUFKIT SOUNDINGS HAVE BACKED OFF ON WIND GUSTS QUITE A BIT...AND
NOW NOT EXPECTING ADVISORY CRITERIA GUSTS...MORE LIKE 30 MPH.
GUSTS MAY BE STRONGER TONIGHT POST FRONTAL.

FAST MOVING NATURE OF STORMS CONTRIBUTED TO MUCH LESS RAINFALL
THAN ORIGINALLY FEARED...WITH AMOUNTS THROUGH 12Z LIKELY TO BE
AROUND AN INCH WITH ISOLATED HIGHER AMOUNTS. THUS...WILL CANCEL
THE FLOOD WATCH. RIVERS MAY STILL GO INTO FLOOD...BUT WIDESPREAD
AREAL FLOOD THREAT HAS DIMINISHED SIGNIFICANTLY.

ON TEMPS...RELIED HEAVILY ON NAM WETBULB TEMP PROGS...AS PRECIP
WILL BE ONGOING AT TIMES THROUGHOUT THE DAY AND INITIAL PROGS
COMPARED FAVORABLY TO OBS.

.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
ISSUED AT 420 AM EST WED JAN 30 2013

FINALLY...ADDITIONAL WAVE WILL APPROACH ON FRIDAY NIGHT...LOW
CHANCE POPS APPEAR REASONABLE.

WINDS TONIGHT POST FRONT MAY GUST TO AROUND 30-35KT AT TIMES...AS
ACCORDING TO BUFKIT SOUNDINGS AND LOW LEVEL WIND PROGS OFF MODELS.
AGAIN THIS IS BELOW ADVISORY CRITERIA.

ON TEMPS...CONSENSUS APPEARED REASONABLE AND ONLY A FEW MINOR
TWEAKS REQUIRED. DID BUMP TEMPS DOWN SLIGHTLY THROUGHOUT WITH COLD
ADVECTION ONGOING UNTIL LATE IN THE PERIOD.

.LONG TERM /SATURDAY THROUGH TUESDAY/...
ISSUED AT 305 AM EST WED JAN 30 2013

AS FAR AS TEMPERATURES ARE CONCERNED MODELS HAVE TRENDED A LITTLE
COLDER OVER THE WEEKEND AND TUESDAY. IN MOST CASES WENT WITH A
BLEND OF ALL BLEND AND CONSALL NUMBERS.

.AVIATION /DISCUSSION FOR THE 301500Z TAF ISSUANCE/...
ISSUED AT 940 AM EST TUE JAN 29 2013

12Z DISCUSSION FOLLOWS.

MOSTLY MVFR CEILINGS THROUGH THE PERIOD WITH GUSTY WINDS THIS
AFTERNOON AND TONIGHT.

WINDS HAVE TEMPORARILY BECOME LIGHT THIS MORNING BUT WILL PICK UP
AGAIN BY THIS AFTERNOON AFTER COLD FRONT MOVES THROUGH AND WITH SOME
AREAS GUSTING UP TO 30 KNOTS LATE TODAY AND TONIGHT..

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

SYNOPSIS...NIELD
NEAR TERM...NIELD
SHORT TERM...NIELD
LONG TERM....JH
AVIATION...JH/RYAN

AREA FORECAST DISCUSSION

NWS TOPEKA KS

418 AM CST WED JAN 30 2013

.DISCUSSION...

MAIN CONCERNS FOR THE FORECAST IS SNOWFALL THIS MORNING AND
ARCTIC AIR RETURNING TO THE CWA ON THURSDAY AND FRIDAY.

TODAY THROUGH FRIDAY MORNING...SNOW HAS BEEN FALLING FOR MUCH OF THE
NIGHT WITH A HEAVY BAND THAT HAS BEEN SLOWLY TRAVERSING THE CWA
THROUGHOUT THE OVERNIGHT HOURS. HEAVIEST BAND DEVELOPED IN THE
DEFORMATION ZONE...NEAR THE AREA OF BEST MID LEVEL FRONTOGENESIS
COUPLED WITH AN AREA OF STRONG OMEGA AND NEGATIVE EPV.
HOWEVER...THE BAND WAS SLOWLY ERODING AS MODELS DEPICT THE
DISSIPATION OF THE FRONTGENESIS AS THE BETTER FORCING MOVES
NORTHEAST. THEREFORE...SHOULD SEE THE HEAVIEST BAND CONTINUE TO
ERODE THROUGHOUT THE MORNING AS IT PUSHES SOUTHEAST. LIGHT SNOW
WILL EVENTUALLY TAPER OFF DURING THE MORNING HOURS WITH THE FAR
EASTERN COUNTIES SEEING AN END AROUND THE NOON HOUR AS THE BETTER
FORCING AGAIN LIFTS TO THE NORTHEAST. BECAUSE OF THE SLOWER
MOVEMENT OF THE PRECIPITATION...OPTED TO EXTEND THE WINTER WEATHER
ADVISORIES TILL 9 AM FOR THE WESTERN COUNTIES AND NOON FOR THE
EASTERN COUNTIES. TOTAL SNOW ACCUMULATIONS WILL BE GREATEST NORTH
OF INTERSTATE 70 WITH 2 TO 4 INCHES AND LOCALLY HIGHER AMOUNTS TO
NEAR 6 INCHES. SOUTH OF INTERSTATE 70...TOTAL ACCUMULATIONS OF 1
TO 3 INCHES WITH LOCALLY HIGHER AMOUNTS POSSIBLE. WINDS PICKING UP
TO 35 MPH WILL ALSO CAUSE CAUSE BLOWING AND DRIFTING AS WELL AS
REDUCED VISIBILITIES ESPECIALLY THIS MORNING. AFTERNOON HIGHS
TODAY WILL REACH INTO THE 20`S TO LOW 30`S.

LONGWAVE TROUGH MOVES OUT OF THE CWA THIS AFTERNOON AS 85KT 500MB
JET CORE ASSOCIATED WITH THE NEXT SHRTWV PUSHES IT TO THE EAST AND
GIVES THE LONGWAVE TROUGH A BIT OF A NEGATIVE TILT OVER THE OHIO VALLEY.
SURFACE LOW DEVELOPS OVER THE WESTERN HIGH PLAINS TONIGHT IN
RESPONSE TO THE SHRTWV...WHICH WILL CAUSE WINDS TO BRIEFLY SWITCH
TO THE WEST/SOUTHWEST THIS EVENING AND TONIGHT. HIGH TEMPERATURES
FOR THE DAY THURSDAY WILL BE REALIZED DURING THE MORNING HOURS
WITH HIGHS IN THE 20`S AS AN ARCTIC COLD FRONT IS PUSHED RAPIDLY
SOUTHEAST ACROSS THE PLAINS AND INTO THE CWA BY THURSDAY MORNING.
SIGNIFICANT CAA WILL LAG BEHIND THE FRONT UNTIL THE AFTERNOON WHERE
TEMPERATURES SHOULD BEGIN DROPPING AFTER THE NOON HOUR.
TEMPERATURES BY SUNSET WILL ONLY BE IN THE TEENS AND LOW 20`S BY
SUNSET. OVERNIGHT LOWS WILL BE BITTERLY COLD WITH LOWS IN THE
SINGLE DIGITS FOR MUCH OF THE CWA. WITH GUSTY WINDS TO AROUND 25
MPH THURSDAY AFTERNOON...COULD SEE WIND CHILLS BELOW ZERO OVER THE
FAR NORTHERN COUNTIES AND SINGLE DIGITS FOR THE REST OF THE AREA.

BYRNE

LONG TERM (FRIDAY AND TUESDAY)...

FRIDAY...THE DEEPER LONGER WAVE-LENGTH UPPER LEVEL TROUGH ACROSS THE
GREAT LAKES AND OH RIVER VALLEY WILL SHIFT EAST INTO NEW ENGLAND AND
THE MID ATLANTIC STATES. THE SFC RIDGE OF HIGH PRESSURE WILL ALSO
SHIFT EAST ACROSS THE MID AND LOWER MS RIVER VALLEY. HIGHS ON FRIDAY
WILL WARM SLIGHTLY...THOUGH DEEPER SNOW COVER ACROSS THE NORTHERN
HALF OF THE CWA MAY KEEP HIGHS IN THE LOWER TO MID 30S...WITH MID
TO UPPER 30S ACROSS THE SOUTHERN COUNTIES.

FRIDAY NIGHT THROUGH WEDNESDAY...THE UPPER LEVEL FLOW WILL BE
WEST-NORTHWEST ACROSS THE PLAINS. EXPECT DRY CONDITIONS.

I KEPT HIGHS COOLER ON SATURDAY ACROSS THE NORTHERN COUNTIES OF THE
CWA DUE TO THE SNOW COVER. SATURDAY HIGHS WILL RANGE FROM THE UPPER
30S ALONG THE NE BORDER TO THE MID AND UPPER 40S SOUTH OF I-70.
HIGHS WILL SLOWLY WARM INTO THE LOWER TO MID 50S SUNDAY THROUGH
TUESDAY.

GARGAN

WOLTERS

.TOP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR
KSZ008>010-020>023-034>038.

WINTER WEATHER ADVISORY UNTIL NOON CST THURSDAY FOR KSZ011-012-
024-026-039-040.

AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

649 AM EST WED JAN 30 2013

PER HPC DESIGNATION OF MOD RISK FOR EXCESSIVE RAINFALL AND
COUNTIES WITH THE LOWEST FFG...WILL ISSUE FLOOD WATCH FOR PORTIONS
OF THE SOUTH AND EAST TODAY AND TONIGHT.

TEMPS WILL REMAIN WELL ABOVE NORMAL TODAY.

RISK FOR SNOW SHOWERS...MAINLY OVER THE FAR NORTH AND
RIDGES...WILL CONTINUE THROUGH THE THURSDAY. TEMPERATURES WILL BE
STEADY OR SLOWLY FALLING WITH GUSTY WINDS CONTINUING.

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
VFR WL DCRS TO MVFR IN SHRA LT MRNG INTO THIS AFTN AS A STG CDFNT
APRCHS FM THE W. SHRA EXTEND WELL OUT AHEAD OF THE FNT. SHOULD
SEE ADDNL DVLPMNT ALG THE FNT THIS AFTN. STLT/MESO/RAOB INSTAB
CHARTS SHOW SOME INSTAB ALG/AHD OF THE FNT. COULD SEE A TS AT ANY
OF THE SITES ESP S OF I-80 THIS AFTN BUT DUE TO PLENTY OF
UNCERTAINTY IN INSTAB/TIMING HAVE KEPT THEM OUT OF THE TAFS ATTM.
INCLUDED A TEMPO FOR +SHRA AND STG WND GUSTS AT ZZV LT MRNG. THIS
MAY HAVE TO BE ADDED TO OTHER SITES AS WELL IN LTR FCSTS. STG LLVL
JET WL KEEP THE THREAT OF LLWS ACRS THE RGN THRU THIS MRNG.
FROPA/WSHFT TO THE W EXPD THIS EVE WITH MVFR CONDS CONTG. EVEN A
FEW SHSN PSBL OVRNGT.

.OUTLOOK.../THURSDAY THROUGH SUNDAY/...
PERIODIC RESTRICTION ARE EXPD THRU THE PD AS SVRL DISTURBANCES
MOVE THRU IN COLD W-NW FLOW. GUSTY W WNDS ARE ALSO EXPTD THU.

AREA FORECAST DISCUSSION...UPDATED

NWS BALTIMORE MD/WASHINGTON DC

629 AM EST WED JAN 30 2013

.SYNOPSIS...
LOW PRESSURE IS CENTERED THIS MORNING OVER MICHIGAN. FROM THIS A
WARM EXTENDS ALONG THE MASON-DIXON LINE WHILE A COLD FRONT
EXTENDS FROM INDIANA TO ARKANSAS. THE COLD FRONT WILL MOVE THROUGH
THE MID ATLANTIC STATES THIS EVENING. ANOTHER COLD FRONT WILL MOVE
THROUGH THE REGION FRIDAY...FOLLOWED BY HIGH PRESSURE SATURDAY.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 11Z...WARM FRONT IS JUST SOUTH OF THE MASON-DIXON LINE. A COLD
FRONT IS THROUGH CHICAGO WITH A PREFRONTAL BAND OF HEAVY SHOWERS
ASSOCIATED WITH A STRONG GULF PLUME THAT EXTENDS FROM BATON ROUGE
TO CINCINNATI. A WIDE SWATH OF TRAILING STRATIFORM IS OVER WRN IL
AND IN.

THIS COLD FRONT AND PREFRONTAL ACTIVITY WILL PROGRESS EAST TOWARD
THE MID-ATLANTIC THROUGH TODAY. THE 08Z HRRR HAS SLOWED THE CURRENT
PREFRONTAL BAND...REACHING THE ALLEGHENY FRONT AROUND 20Z WHICH
SEEMS TO BE A REASONABLE TIMEFRAME. FLASH FLOOD WATCH IS IN
EFFECT FOR COUNTIES ALONG THE ALLEGHENY FRONT AS WELL AS
HAMPSHIRE/HARDY WHERE 6 HR FLASH FLOOD GUIDANCE IS AROUND AN INCH
/1-2 INCHES ARE EXPECTED FOR THOSE COUNTIES/. ANY OTHER FLOODING
LOOKS TO BE IN URBAN AREAS LIKE BALT-WASH. OTHERWISE A WELCOME
HEAVY RAINFALL THOUGH DAMAGING WINDS ARE A REAL THREAT.

SEVERE THREAT. VERY STRONG SHEAR/SLY LLJ AND VERY LOW CAPE WILL
RESULT IN A DYNAMIC BAND/QLCS LINE SPREADING EAST ACROSS THE CWA
LATER THIS AFTERNOON THROUGH THE EVENING HOURS. GUSTS IN EXCESS OF
50 KT POSSIBLE WITH THIS BAND ACROSS THE LWX CWA. KEPT THUNDER
CHANCES AT JUST CHANCE THOUGH THE MIDWEST HAS HAD A FAIR SHARE OF
THUNDER TONIGHT. THIS COLD FRONT MAY FORM AN AXIS FOR BOTH HEAVY
RAIN AND TORNADOES. STRONG LOW LEVEL WIND SHEAR WILL ALLOW FOR
HORIZONTAL VORTICITY ROLLS. THE WARM FRONT AND A FEW MILES INTO
THE COLD SIDE ARE TEXTBOOK PRIME AREAS FOR TORNADOES. PROGRESSION
OF THIS WARM FRONT TODAY WILL BE KEY.

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
WARM EVENING AHEAD OF THE PREFRONTAL RAIN BANDS. PRECIP SLOWLY
CUTS OF WITH STRATIFORM TRAILING MAIN BAND FOR A FEW HOURS.
UPSLOPE SNOW OF ONLY A COUPLE INCHES. NO WINTER WEATHER ADVISORY
EXPECTED. WITH COLD AIR ADVECTION...MIN TEMPS TONIGHT WILL BE
SIMILAR TO THE HIGH TEMPS FOR THURSDAY.

.LONG TERM /THURSDAY THROUGH TUESDAY/...
AFTR TUE AND TDA`S VERY WARM TEMPS THE RGN WL RETURN TO MORE
NORMAL LATE JAN/ERLY FEB TEMPS FOR THE XTND PD.

HIGH PRES WL BUILD INTO THE RGN FRI AFTN AND SAT. HIGHS GNRLY IN
THE U30S E OF THE MTNS. LOWS IN THE 20S.

HIGHS CONT IN THE U30S/L40S SUN THRU TUE. LOWS IN THE MU20S.

.AVIATION /11Z WEDNESDAY THROUGH SUNDAY/...
MVFR CIGS SPREADING NORTH FROM SRN VA HAVE CROSSED IAD AND WILL
MOVE ACROSS THE DC METRO THROUGH THE MID MORNING HOURS. SLY LOW
LEVEL WIND SHEAR INCREASES TODAY PEAKING TONIGHT JUST AHEAD OF A
COLD FRONT. CHANCES FOR THUNDER WITH VERY GUSTY WINDS AND HEAVY
RAINFALL...ON THE ORDER OF 50 KT. WINDS SHIFT WEST AND DECREASE
LATE TONIGHT.

GUSTY NW WINDS XPCTD THU. SKIES/CIGS SHOULD BE VFR. VFR CONDITIONS
ARE EXPECTED MOST OF THE TIME THU NIGHT THROUGH SUNDAY.

.MARINE...
SLY GALE EXPECTED BY LATE AFTERNOON CONTINUING UNTIL THE COLD FRONT
CROSSES LATE TONIGHT.

HIGH PRES BLDG INTO THE WATERS WL LKLY CONT TO CAUSE STRONG WIND
GUSTS DURG THU. HV ISSUED A GALE WRNG FOR CHES BAY/LWR TIDAL
PTMC...AND A STRONG SCA FOR THE RMDR OF THE WATERS.

A COLD FRONT WILL PASS THROUGH THURSDAY NIGHT, GUSTY WINDS ARE
EXPECTED BEHIND THE FRONT FRIDAY. HIGH PRES OVR THE WATERS SAT.
ANOTHER COLD FRONT MAY IMPACT THE WATERS SUNDAY.

.TIDES/COASTAL FLOODING...
COASTAL FLOOD ADVISORY IN EFFECT THIS EVENING AND TONIGHT FOR ANNE
ARUNDEL AND NORTH...AND DC/ALEXANDRIA. A SOUTHERLY FLOW WILL
INCREASE TODAY WITH GUSTS AROUND 35 KNOTS DURING THE AFTERNOON AND
EVENING HOURS. THE STRONG SOUTHERLY FLOW WILL PUSH WATER UP THE
CHESAPEAKE BAY AND THE TIDAL POTOMAC RIVER UNTIL THE COLD FRONT
PASSES LATE TONIGHT. SINCE THE FLOW WILL BE SLY ONLY THE WATER IN
THE BAY IS EXPECTED TO SURGE NORTHWARD. HAD THIS BEEN A
SOUTHEASTERLY GALE...THEN ADDED WATER WOULD LIKELY CAUSE MODERATE
FLOODING. WIND SHOULD BE STRONG ENOUGH TO CAUSE WIDESPREAD MINOR
INUNDATION BEFORE HIGH TIDE...THEN CONTINUE UNTIL THE COLD
FRONT...NOT NECESSARILY ONLY NEAR HIGH TIDE. LATER SHIFTS WILL
HAVE TO MONITOR WATER RISE FROM LOWER PARTS OF THE BAY.

NW WINDS WILL ALLOW FOR TIDAL ANOMALIES TO DECREASE THU.

$$
UPDATE...JACKSON
PREVIOUS DISCUSSION...JACKSON/WOODY!

AREA FORECAST DISCUSSION

NWS BINGHAMTON NY

1028 AM EST WED JAN 30 2013

.SYNOPSIS...
UNSEASONABLY WARM AIR WILL OVERSPREAD THE REGION TODAY IN ADVANCE
OF A STRONG COLD FRONT. SHOWERS AND SCATTERED THUNDERSTORMS WILL
DEVELOP THIS AFTERNOON IN THIS MOIST AIR MASS...AND THE RAIN WILL
BE HEAVY AT TIMES. COLDER AIR BEHIND THE FRONT WILL TRIGGER LAKE
EFFECT SNOWS ACROSS CENTRAL NEW YORK ON THURSDAY AND THURSDAY
NIGHT.

.NEAR TERM /THROUGH TONIGHT/...
9 AM UPDATE...
YET ANOTHER UPDATE TO BUMP TEMPS DOWN AT KAVP WITH SENSOR READING
AROUND 4 DEGREES TOO WARM. NO OTHER CHGS NEEDED AT THIS TIME AS A
MAJOR WX EVENT IS IMPENDING FOR TONIGHT.

730 AM UPDATE...
QUICK UPDATE TO BUMP CURRENT TEMPS UP IN WYOMING/LACKAWANNA VLYS
AS KAVP IS NOW UP TO 62F. MESONET SITES IN THAT AREA ARE CURRENTLY
IN THE MID-50S THUS NOT OUT OF THE QUESTION THAT SCRANTON WILKES-
BARRE AIRPORT IS IN THE LOW 60S AS IT SITS AROUND 1000 FEET UP AND
WITH STRONG INVERSION IN PLACE PER KALY/KOKX 12Z RAOBS.

630 AM UPDATE...MINOR T/TD TWEEKS IN THE NEAR TERM...RAISING MAXES
BY A FEW DEG MAINLY FINGER LAKES AND CNTRL SRN TIER. ALSO ADDED
PC SKIES FOR PARTS OF THE RGN THIS MRNG. CRUDE XTRAPOLATION OF
LEADING PCPN SHIELD INDICATES ARRIVAL TIME ARND 1730Z INTO WRN STEUBEN.
WE`LL SEE IF THIS HOLDS. NO OTHER CHGS. PREV BLO...

510 AM UPDATE...BUMPED UP START TIME OF THE FLOOD WATCH TO 21Z.
PREV BLO..

LOTS TO LOOK AT THIS FCST PCKG. MAIN FOCUS IS ON THE APRCHNG
CDFNT AND DIGGING UPR TROF...WHICH WILL BRING A ROUND OF +RA AND
WIND TO THE RGN STARTING THIS AFTERNOON INTO THE OVRNGT HRS.

THERE IS TREMENDOUS BUST POTNL WITH THIS FCST...STARTING OFF WITH
MAX TEMPS TDA. WE ARE FCSTNG MAXES INTO THE LOWER 60S MAINLY W OF
I-81...BUT IF WE GET SOME BREAKS OF SUN LATER THIS MRNG THIS FCST
WILL BE ON THE COOL SIDE. WE ALSO NOTE THAT TEMPS ARE CRNTLY (AS
OF 330 AM) A60 OVER MOST OF OH. ATTM WE PLAYED IT CLOSE TO THE
VEST...WITH EXPECTATION THAT ANY SUNSHINE WILL BE LIMITED. BUT IT
IS SOMETHING TO WATCH.

MDLS HAVE BEEN LEANING SLOWER WITH THIS DYNAMIC SYSTEM...AND OUR
FCST REFLECTS THIS. DO NOT XPCT MUCH PCPN BEFORE 18Z...WITH THE
HEAVIEST RAIN LIKELY TO FALL VERY LATE AFTN/EVNG. WE EXPANDED THE
FFA TO INCLUDE THE ENTIRE FCST AREA...MAIN THREAT BEING +RA AND
FLASH FLOODING...AS MDLS ARE SHIFTING THE HEAVY PCPN AXIS FURTHER
TO THE WEST. WE STARTED THE FLOOD WATCH AT 00Z EXPECTING THAT ANY
HYDRO ISSUES WILL BE AFTER THIS TIME...BUT DAY SHIFT MAY HAVE TO
MOVE UP THE START TIME IF PCPN WORKS IN EARLIER THAN XPCTD.

ATTM WE XPCT RAINFALL TO AVG SOMEWHERE BETWEEN 1 AND 2 INCHES....LCLY
HIER AMTS IN THE SRLY UPSLOPE FAVORED AREAS...LOWEST AMTS PRBLY IN
THE LAKE PLAIN. ADDED TSRA TO THE MIX THIS AFTN/EVNG GIVEN WHAT`S
BEEN OCCURRING UPSTREAM AND FCST SI`S FROM 0 TO -2. STRONG DYNAMICS
IN ALMOST ANY FIELD YOU LOOK AT...INCLUDING IMPRSV UPR LVL DVRGNC
ASSCD WITH THE RR QUAD OF AN UPR LVL JET COUPLED WITH STRONG LOW
LVL FNTL CONVERGENCE SO CAT POPS CONTINUE TO LOOK GOOD. STEADIER
RAINS WILL END LATER TNGT FROM W TO E...PSBLY MIXING WITH -SHSN
TWDS DAYBREAK.

POTNL FOR SOME VERY GUSTY WINDS WITH ANY CONVECTION THAT DVLPS
NEAR/ALONG THE FNT. GIVEN THIS AND THE STRONG WINDS XPCTD BEHIND
THE CDFNT ON THU...WE ISSUED A HIGH WIND WATCH FOR THE ENTIRE
RGN.

RECORD TEMPS FOR TDA INCLUDE 54F AT SYR (2006/1914), 52 AT BGM
(1974), AND 66 AT AVP (1947). SYR AND BGM RECORDS ARE GONERS.

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
XPCT STRONG WINDS ON THU. NAM/GFS MOS GDNC SHOWING SUSTAINED 25
TO 30 WHICH IS ONE OF THE BETTER INDICATORS SUGGESTING WARNING
CRITERIA WINDS ALONG THE LAKE PLAIN. ISALLOBARIC FIELDS ALSO MORE
IMPRSV THAN PREV WARNING/ADVISORY EVENT. POTNL FOR WARNING CRITERIA
SPCLY ACRS THE LAKE PLAIN AND PSBLY ADJACENT COUNTIES...WITH AN
ADVISORY APPEARING LIKELY FOR THE REMAINDER OF THE CWA.

AS COLDER AIR WORKS IN ON THU...LES WILL DVLP EAST OF LAKE
ONTARIO. PROFILES AND TRAJECTORIES LOOK FVRBL THU AFTN INTO THU
NGT FOR SIG ACCUMS AS 850 TEMPS FALL TO -18C...SO AN LES WATCH WAS
ISSUED. THIS ACTIVITY IS XPCTD TO DROP SWD LATE THU NGT ON 290-300
FLOW INTO ONON/MAD/SRN ONEIDA. THIS BAND MAY LIFT BACK NWD ON FRI
NGT AS LOW LVL FLOW BCMS SWLY AHEAD OF THE NXT CLIPPER.

.LONG TERM /SATURDAY THROUGH TUESDAY/...
LK EFFECT SNOW STARTING OFF PD ACRS FAR NRN NY WL TRANSITION NORTH
OF THE REGION BY 06Z SATURDAY AS SFC RIDGE NOSES INTO AREA. WK UL
TROF WL MV THRU SAT AFTN WITH EC BEING STRONGEST WITH VORT MAX AND
GFS WEAKER. THEREFORE HV GONE WITH ONLY CHC POPS AT THIS TIME PER HPC
GUIDANCE. POPS WL INCREASE SAT NGT AND SUN AS ANOTHER WV AND ASSOC
SFC LOW DROPS THRU THE CWA THO ONLY TO BTWN 40-50%.

12Z GUIDANCE HAS COME INTO BETTER AGREEMENT WITH WV DROPPING INTO
NERN U.S. AND DVLPNG SFC LOPRES SUN AFTN/EVNG SOMEWHERE IN THE GULF
OF MAINE. ENERGY WL LKLY NOT TRANSFER OFF THE COAST QUICKLY ENUF TO
GIVE US A THREAT FOR WIDESPREAD SNOW FOR EARLY NEXT WEEK.

TEMPS DRG THE EXTNDD PORTION WL SETTLE OUT CLOSE TO SEASONAL VALUES.

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
12Z WED UPDATE... ONE OF THE MAIN AVIATION IMPACTS THE NEXT 12-18
HRS WILL BE LLWS...AS A VERY STG LOW-LVL JET DVLPS OVER THE
RGN...WITH AN INVERSION ALSO IN PLACE IN THE LWST 2K FT...TO KEEP
THE STGST WINDS JUST OFF THE SFC. THIS HAZARD WAS CARRIED AT ALL
SITES. THERE IS SOME PSBLTY THAT WARMING SFC TEMPS THIS AFTN WILL
BE ENOUGH TO ERODE THE INVERSION...AND BRING STG GUSTY WINDS
(35-40 KT) ALL THE WAY TO THE SFC. ALTHOUGH WE FEEL THIS IS A LOW
PROB OCCURRENCE...KSYR AND KBGM MAY BE THE MOST PROBABLE SITES FOR
THIS (DOWNSLOPING SRLY FLOW AT KSYR AND ADDED ELEVATION AT KBGM).
SUCH TRENDS WILL OBVIOUSLY BE WATCHED CLOSELY THROUGHOUT THE DAY.

EARLY THIS MRNG...SOME LWR CLDS AND LGT FOG COULD OCNLY FLOAT
THROUGH AT KBGM/KAVP. OTHERWISE...MAINLY VFR SHOULD PREVAIL INTO
EARLY AFTN.

FROM 19-22Z ONWARD THROUGH THE EVE HRS...AS THE MAIN COLD FRNTL BNDRY
SLOWLY APPROACHES...RAIN SHOULD BECOME STEADIER IN NATURE...WITH
PREVAILING MVFR CONDS. EMBEDDED CONVECTIVE ELEMENTS ARE CERTAINLY
NOT OUT OF THE QUESTION...GIVEN THE STRENGTH OF THIS SYSTEM...AND
THE UNSEASONABLE WARMTH IN PLACE. HOWEVER...WE DON`T FEEL
CONFIDENT ENOUGH TO INSERT THUNDER OR EXCESSIVE WIND GUSTS (40+
KT) ATTM. ONCE AGN...RADAR TRENDS WILL BE CLOSELY MONITORED
THROUGHOUT THE DAY.

FROPA SHOULD OCCUR FM 06-09Z THU...WITH AN ABRUPT WIND SHIFT TO
WRLY...AND QUITE AN INCREASE IN THE WINDS AS WELL (GUSTS OF 35-45 KT).

.OUTLOOK...

THU/FRI/SAT/SUN...OCNL MVFR TO IFR RESTRICTIONS...IN SHSN.

.HYDROLOGY...
CONSENSUS OF MODEL AND MAN MADE GUID PROGS PUTS 1 TO UP TO 2.5
INCHES WITH THE HEAVIEST RAIN AXIS FURTHER WEST ACROSS THE FINGER
LAKES AND CHEMUNG BASINS OF NY. WILL HAVE TWO BATCHES WITH THE
INITIAL BATCH ALREADY IN WRN PA AND WRN NY NOW. THIS FIRST BATCH
MOVES QUICKLY THROUGH THIS AFTN. RAINFALL THIS AFTN UP TO HALF AN
INCH. QUICK RESPONSE ON STREAMS BUT NO FLOODING INITIALLY. THE
COLD FRONT WILL COME THROUGH LATE EVE AND EARLY MORNING WITH MORE
HEAVY RAIN. ANOTHER QUICK INCH IN LESS THAN 6 HOURS WHICH WILL BE
MOSTLY RUNOFF. STREAMS AND RIVERS WILL RESPOND QUICKLY. FLASH
FLOODING POSSIBLE...FOLLOWED BY MINOR RIVER FLOODING.

FLOOD WATCH CONTINUES FOR ENTIRE CWA STARTING AT 4 PM INTO
THURSDAY MORNING. RIVER FLOOD WARNINGS JUST ISSUED FOR
WEST BRANCH DELAWARE RIVER AT WALTON
TIOUGHNIOGA RIVER AT CORTLAND
CHENANGO RIVER AT SHERBURNE
SUSQUEHANNA RIVER AT VESTAL
SUSQUEHANNA RIVER AT WAVERLY/SAYRE
SUSQUEHANNA RIVER AT TOWANDA
SUSQUEHANNA RIVER AT MESHOPPEN
SUSQUEHANNA RIVER NEAR WILKES-BARRE

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...FLOOD WATCH FROM 4 PM EST THIS AFTERNOON THROUGH THURSDAY
MORNING FOR PAZ038>040-043-044-047-048-072.
HIGH WIND WATCH FROM 7 PM EST THIS EVENING THROUGH THURSDAY
EVENING FOR PAZ038>040-043-044-047-048-072.
NY...FLOOD WATCH FROM 4 PM EST THIS AFTERNOON THROUGH THURSDAY
MORNING FOR NYZ009-015>018-022>025-036-037-044>046-
055>057-062.
HIGH WIND WATCH FROM 7 PM EST THIS EVENING THROUGH THURSDAY
EVENING FOR NYZ009-015>018-022>025-036-037-044>046-
055>057-062.
LAKE EFFECT SNOW WATCH FROM THURSDAY MORNING THROUGH FRIDAY
MORNING FOR NYZ009.

$$
SYNOPSIS...
NEAR TERM...PVN
SHORT TERM...
LONG TERM...PVN
AVIATION...MLJ
HYDROLOGY...

AREA FORECAST DISCUSSION

NWS BINGHAMTON NY

858 AM EST WED JAN 30 2013

510 AM UPDATE...BUMPED UP START TIME OF THE FLOOD WATCH TO 21Z.
PREV BLO..

LOTS TO LOOK AT THIS FCST PCKG. MAIN FOCUS IS ON THE APRCHNG
CDFNT AND DIGGING UPR TROF...WHICH WILL BRING A ROUND OF +RA AND
WIND TO THE RGN STARTING THIS AFTERNOON INTO THE OVRNGT HRS.

POTNL FOR SOME VERY GUSTY WINDS WITH ANY CONVECTION THAT DVLPS
NEAR/ALONG THE FNT. GIVEN THIS AND THE STRONG WINDS XPCTD BEHIND
THE CDFNT ON THU...WE ISSUED A HIGH WIND WATCH FOR THE ENTIRE
RGN.

RECORD TEMPS FOR TDA INCLUDE 54F AT SYR (2006/1914), 52 AT BGM
(1974), AND 66 AT AVP (1947). SYR AND BGM RECORDS ARE GONERS.

TEMPS DRG THE EXTNDD PORTION WL SETTLE OUT CLOSE TO SEASONAL VALUES.

.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
12Z WED UPDATE... ONE OF THE MAIN AVIATION IMPACTS THE NEXT 12-18
HRS WILL BE LLWS...AS A VERY STG LOW-LVL JET DVLPS OVER THE
RGN...WITH AN INVERSION ALSO IN PLACE IN THE LWST 2K FT...TO KEEP
THE STGST WINDS JUST OFF THE SFC. THIS HAZARD WAS CARRIED AT ALL
SITES. THERE IS SOME PSBLTY THAT WARMING SFC TEMPS THIS AFTN WILL
BE ENOUGH TO ERODE THE INVERSION...AND BRING STG GUSTY WINDS
(35-40 KT) ALL THE WAY TO THE SFC. ALTHOUGH WE FEEL THIS IS A LOW
PROB OCCURRENCE...KSYR AND KBGM MAY BE THE MOST PROBABLE SITES FOR
THIS (DOWNSLOPING SRLY FLOW AT KSYR AND ADDED ELEVATION AT KBGM).
SUCH TRENDS WILL OBVIOUSLY BE WATCHED CLOSELY THROUGHOUT THE DAY.

EARLY THIS MRNG...SOME LWR CLDS AND LGT FOG COULD OCNLY FLOAT
THROUGH AT KBGM/KAVP. OTHERWISE...MAINLY VFR SHOULD PREVAIL INTO
EARLY AFTN.

FROPA SHOULD OCCUR FM 06-09Z THU...WITH AN ABRUPT WIND SHIFT TO
WRLY...AND QUITE AN INCREASE IN THE WINDS AS WELL (GUSTS OF 35-45 KT).

.OUTLOOK...

THU/FRI/SAT/SUN...OCNL MVFR TO IFR RESTRICTIONS...IN SHSN.

.HYDROLOGY...
CONSENSUS OF MODEL AND MAN MADE GUID PROGS PUTS UP TO 2 INCHES OF
QPF OVER THE WRN CATS AND PARTS OF NEPA. THIS SEEMS RATHER HIGH
FOR A FAST MVG COLD FNT BUT WE DO HAVE A WV DVLPG ALONG THE FNT
THAT DVLPS GOOD LL CONV THAT IN TURN BRINGS A PD OF SLY OR SELY
INFLOW...MAINLY INTO THE CATS. IF WE SEE THE WORST CASE SCENARIO
THERE WLD BE SOME MINOR FLOOD PRBLMS ON THE MAIN RVRS. OF BIGGER
CNCRN TO ME WLD BE THE SMALLER STREAMS WHERE THIS PTNL RAIN WLD
FALL OVER A RELATIVELY SMALL WINDOW...ABT 6 HRS. OTR FACTOR TO
ALWAYS CONSIDER IS THE ONGOING PRBLM WITH FLOOD DAMAGED STREAM BEDS
IN THE AREA FROM PAST EVENTS. WILL ISSUE A GENERIC FLOOD WATCH FOR
THE WESTERN CATS AND MUCH OF NEPA TO CVR THE RAIN AND FLOOD PTNL.

$$
SYNOPSIS...
NEAR TERM...PVN
SHORT TERM...
LONG TERM...PVN
AVIATION...MLJ
HYDROLOGY...

AREA FORECAST DISCUSSION

NWS BINGHAMTON NY

738 AM EST WED JAN 30 2013

.NEAR TERM /THROUGH TONIGHT/...
730 AM UPDATE...
QUICK UPDATE TO BUMP CURRENT TEMPS UP IN WYOMING/LACKAWANNA VLYS
AS KAVP IS NOW UP TO 62F. MESONET SITES IN THAT AREA ARE CURRENTLY
IN THE MID-50S THUS NOT OUT OF THE QUESTION THAT SCRANTON WILKES-
BARRE AIRPORT IS IN THE LOW 60S AS IT SITS AROUND 1000 FEET UP AND
WITH STRONG INVERSION IN PLACE PER KALY/KOKX 12Z RAOBS.

510 AM UPDATE...BUMPED UP START TIME OF THE FLOOD WATCH TO 21Z.
PREV BLO..

LOTS TO LOOK AT THIS FCST PCKG. MAIN FOCUS IS ON THE APRCHNG
CDFNT AND DIGGING UPR TROF...WHICH WILL BRING A ROUND OF +RA AND
WIND TO THE RGN STARTING THIS AFTERNOON INTO THE OVRNGT HRS.

POTNL FOR SOME VERY GUSTY WINDS WITH ANY CONVECTION THAT DVLPS
NEAR/ALONG THE FNT. GIVEN THIS AND THE STRONG WINDS XPCTD BEHIND
THE CDFNT ON THU...WE ISSUED A HIGH WIND WATCH FOR THE ENTIRE
RGN.

RECORD TEMPS FOR TDA INCLUDE 54F AT SYR (2006/1914), 52 AT BGM
(1974), AND 66 AT AVP (1947). SYR AND BGM RECORDS ARE GONERS.

TEMPS DRG THE EXTNDD PORTION WL SETTLE OUT CLOSE TO SEASONAL VALUES.

.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...
12Z WED UPDATE... ONE OF THE MAIN AVIATION IMPACTS THE NEXT 12-18
HRS WILL BE LLWS...AS A VERY STG LOW-LVL JET DVLPS OVER THE
RGN...WITH AN INVERSION ALSO IN PLACE IN THE LWST 2K FT...TO KEEP
THE STGST WINDS JUST OFF THE SFC. THIS HAZARD WAS CARRIED AT ALL
SITES. THERE IS SOME PSBLTY THAT WARMING SFC TEMPS THIS AFTN WILL
BE ENOUGH TO ERODE THE INVERSION...AND BRING STG GUSTY WINDS
(35-40 KT) ALL THE WAY TO THE SFC. ALTHOUGH WE FEEL THIS IS A LOW
PROB OCCURRENCE...KSYR AND KBGM MAY BE THE MOST PROBABLE SITES FOR
THIS (DOWNSLOPING SRLY FLOW AT KSYR AND ADDED ELEVATION AT KBGM).
SUCH TRENDS WILL OBVIOUSLY BE WATCHED CLOSELY THROUGHOUT THE DAY.

EARLY THIS MRNG...SOME LWR CLDS AND LGT FOG COULD OCNLY FLOAT
THROUGH AT KBGM/KAVP. OTHERWISE...MAINLY VFR SHOULD PREVAIL INTO
EARLY AFTN.

FROPA SHOULD OCCUR FM 06-09Z THU...WITH AN ABRUPT WIND SHIFT TO
WRLY...AND QUITE AN INCREASE IN THE WINDS AS WELL (GUSTS OF 35-45 KT).

.OUTLOOK...

THU/FRI/SAT/SUN...OCNL MVFR TO IFR RESTRICTIONS...IN SHSN.

$$
SYNOPSIS...
NEAR TERM...PVN
SHORT TERM...
LONG TERM...PVN
AVIATION...MLJ
HYDROLOGY...

AREA FORECAST DISCUSSION

NWS BINGHAMTON NY

650 AM EST WED JAN 30 2013

.NEAR TERM /THROUGH TONIGHT/...
630 AM UPDATE...MINOR T/TD TWEEKS IN THE NEAR TERM...RAISING MAXES
BY A FEW DEG MAINLY FINGER LAKES AND CNTRL SRN TIER. ALSO ADDED
PC SKIES FOR PARTS OF THE RGN THIS MRNG. CRUDE XTRAPOLATION OF
LEADING PCPN SHIELD INDICATES ARRIVAL TIME ARND 1730Z INTO WRN STEUBEN.
WE`LL SEE IF THIS HOLDS. NO OTHER CHGS. PREV BLO...

510 AM UPDATE...BUMPED UP START TIME OF THE FLOOD WATCH TO 21Z.
PREV BLO..

LOTS TO LOOK AT THIS FCST PCKG. MAIN FOCUS IS ON THE APRCHNG
CDFNT AND DIGGING UPR TROF...WHICH WILL BRING A ROUND OF +RA AND
WIND TO THE RGN STARTING THIS AFTERNOON INTO THE OVRNGT HRS.

POTNL FOR SOME VERY GUSTY WINDS WITH ANY CONVECTION THAT DVLPS
NEAR/ALONG THE FNT. GIVEN THIS AND THE STRONG WINDS XPCTD BEHIND
THE CDFNT ON THU...WE ISSUED A HIGH WIND WATCH FOR THE ENTIRE
RGN.

RECORD TEMPS FOR TDA INCLUDE 54F AT SYR (2006/1914), 52 AT BGM
(1974), AND 66 AT AVP (1947). SYR AND BGM RECORDS ARE GONERS.

TEMPS DRG THE EXTNDD PORTION WL SETTLE OUT CLOSE TO SEASONAL VALUES.

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
12Z WED UPDATE... ONE OF THE MAIN AVIATION IMPACTS THE NEXT 12-18
HRS WILL BE LLWS...AS A VERY STG LOW-LVL JET DVLPS OVER THE
RGN...WITH AN INVERSION ALSO IN PLACE IN THE LWST 2K FT...TO KEEP
THE STGST WINDS JUST OFF THE SFC. THIS HAZARD WAS CARRIED AT ALL
SITES. THERE IS SOME PSBLTY THAT WARMING SFC TEMPS THIS AFTN WILL
BE ENOUGH TO ERODE THE INVERSION...AND BRING STG GUSTY WINDS
(35-40 KT) ALL THE WAY TO THE SFC. ALTHOUGH WE FEEL THIS IS A LOW
PROB OCCURRENCE...KSYR AND KBGM MAY BE THE MOST PROBABLE SITES FOR
THIS (DOWNSLOPING SRLY FLOW AT KSYR AND ADDED ELEVATION AT KBGM).
SUCH TRENDS WILL OBVIOUSLY BE WATCHED CLOSELY THROUGHOUT THE DAY.

EARLY THIS MRNG...SOME LWR CLDS AND LGT FOG COULD OCNLY FLOAT
THROUGH AT KBGM/KAVP. OTHERWISE...MAINLY VFR SHOULD PREVAIL INTO
EARLY AFTN.

FROPA SHOULD OCCUR FM 06-09Z THU...WITH AN ABRUPT WIND SHIFT TO
WRLY...AND QUITE AN INCREASE IN THE WINDS AS WELL (GUSTS OF 35-45 KT).

.OUTLOOK...

THU/FRI/SAT/SUN...OCNL MVFR TO IFR RESTRICTIONS...IN SHSN.

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...FLOOD WATCH FROM 4 PM EST THIS AFTERNOON THROUGH THURSDAY
MORNING FOR PAZ038>040-043-044-047-048-072.
HIGH WIND WATCH FROM THIS EVENING THROUGH THURSDAY EVENING FOR
PAZ038>040-043-044-047-048-072.
NY...FLOOD WATCH FROM 4 PM EST THIS AFTERNOON THROUGH THURSDAY
MORNING FOR NYZ009-015>018-022>025-036-037-044>046-
055>057-062.
HIGH WIND WATCH FROM THIS EVENING THROUGH THURSDAY EVENING FOR
NYZ009-015>018-022>025-036-037-044>046-055>057-062.
LAKE EFFECT SNOW WATCH FROM THURSDAY MORNING THROUGH FRIDAY
MORNING FOR NYZ009.

$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...PVN
AVIATION...MLJ
HYDROLOGY...

AREA FORECAST DISCUSSION

NWS BINGHAMTON NY

512 AM EST WED JAN 30 2013

.NEAR TERM /THROUGH TONIGHT/...
510 AM UPDATE...BUMPED UP START TIME OF THE FLOOD WATCH TO 21Z.
PREV BLO..

LOTS TO LOOK AT THIS FCST PCKG. MAIN FOCUS IS ON THE APRCHNG
CDFNT AND DIGGING UPR TROF...WHICH WILL BRING A ROUND OF +RA AND
WIND TO THE RGN STARTING THIS AFTERNOON INTO THE OVRNGT HRS.

ATTM WE XPCT RAINFALL TO AVG SOMEWHERE BETWEEN 1 AND 2 INCHES....LCLY
HIER AMTS IN THE SRLY UPSLOPE FAVORED AREAS...LOWEST AMTS PRBLY IN
THE LAKE PLAIN. ADDED TSRA TO THE MIX THIS AFTN/EVNG GIVEN WHAT`S
BEEN OCCRRING UPSTREAM AND FCST SI`S FROM 0 TO -2. STRONG DYNAMICS
IN ALMOST ANY FLEID YOU LOOK AT...INCLUDING IMPRSV UPR LVL DVRGNC
ASSCD WITH THE RR QUAD OF AN UPR LVL JET COUPLED WITH STRONG LOW
LVL FNTL CONVERGENCE SO CAT POPS CONTINUE TO LOOK GOOD. STEADIER
RAINS WILL END LATER TNGT FROM W TO E...PSBLY MIXING WITH -SHSN
TWDS DAYBREAK.

POTNL FOR SOME VERY GUSTY WINDS WITH ANY CONVECTION THAT DVLPS
NEAR/ALONG THE FNT. GIVEN THIS AND THE STRONG WINDS XPCTD BEHIND
THE CDFNT ON THU...WE ISSUED A HIGH WIND WATCH FOR THE ENTIRE
RGN.

RECORD TEMPS FOR TDA INCLUDE 54F AT SYR (2006/1914), 52 AT BGM
(1974), AND 66 AT AVP (1947). SYR AND BGM RECORDS ARE GONERS.

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
XPCT STRONG WINDS ON THU. NAM/GFS MOS GDNC SHOWING SUSTAINED 25
TO 30 WHICH IS ONE OF THE BETTER INDICATORS SUGGESTING WARNING
CRITERIA WINDS ALONG THE LAKE PLAIN. ISALOBARIC FIELDS ALSO MORE
IMPRSV THAN PREV WARNING/ADVISORY EVENT. POTNL FOR WARNING CRITERIA
SPCLY ACRS THE LAKE PLAIN AND PSBLY ADJACENT COUNTIES...WITH AN
ADVISORY APPEARING LIKELY FOR THE REMAINDER OF THE CWA.

TEMPS DRG THE EXTNDD PORTION WL SETTLE OUT CLOSE TO SEASONAL VALUES.

.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
06Z WED UPDATE... THE PRIMARY AVIATION IMPACT THE NEXT 12-24 HRS
WILL LIKELY BE LLWS...AS A VERY STG LOW-LVL JET DVLPS OVER THE
RGN...WITH AN INVERSION ALSO IN PLACE IN THE LWST 2K FT...TO KEEP
THE STGST WINDS JUST OFF THE SFC. THIS HAZARD WAS CARRIED AT ALL SITES.
THERE IS SOME PSBLTY THAT WARMING SFC TEMPS THIS AFTN WILL BE
ENOUGH TO ERODE THE INVERSION...AND BRING STG GUSTY WINDS (35-40
KT) ALL THE WAY TO THE SFC. ALTHOUGH WE FEEL THIS IS A LOW PROB
OCCURRENCE...KSYR AND KBGM MAY BE THE MOST PROBABLE SITES FOR THIS
(DOWNSLOPING SRLY FLOW AT KSYR AND ADDED ELEVATION AT KBGM). SUCH
TRENDS WILL OBVIOUSLY BE WATCHED CLOSELY THROUGHOUT THE DAY.

EARLY THIS MRNG...LWR STRATUS CLDS AND FOG ARE EXPECTED TO PREVAIL
AT KELM/KBGM/KITH/KAVP...WITH PERSISTENT IFR. KSYR AND KRME SHOULD
STAY MVFR TO VFR. FROM ABT 14-21Z...LWR CLDS COULD WELL BREAK FOR
A TIME AT KELM/KSYR...WITH MOSTLY VFR. ELSEWHERE...BKN-OVC MVFR
CIGS ARE EXPECTED TO PREVAIL.

FROM ABT 21Z ONWARD THROUGH THE EVE HRS...AS THE MAIN COLD FRNTL
BNDRY SLOWLY APPROACHES...RAIN SHOULD BECOME STEADIER IN
NATURE...WITH PREVAILING MVFR CONDS. EMBEDDED CONVECTIVE ELEMENTS
ARE CERTAINLY NOT OUT OF THE QUESTION...GIVEN THE STRENGTH OF THIS
SYSTEM...AND THE UNSEASONABLE WARMTH IN PLACE. HOWEVER...WE DON`T
FEEL CONFIDENT ENOUGH TO INSERT THUNDER OR EXCESSIVE WIND GUSTS
(40+ KT) ATTM. ONCE AGN...RADAR TRENDS WILL BE CLOSELY MONITORED
THROUGHOUT THE DAY.

FOR MOST SITES...FROPA SHOULD OCCUR FM 06-09Z THU (JUST BEYOND THE
VALID TAF PD).

.OUTLOOK...

THU/FRI/SAT/SUN...OCNL MVFR TO IFR RESTRICTIONS...IN SHSN.

LONG TERM...PVN
AVIATION...MLJ/RRM
HYDROLOGY...

AREA FORECAST DISCUSSION

NWS LA CROSSE WI

353 AM CST WED JAN 30 2013

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
353 AM CST WED JAN 30 2013

MAIN FORECAST CONCERNS THIS PACKAGE...WINTER STORM/SNOW AMOUNTS/
WINDS TODAY...TEMPERATURE TRENDS AND INTERMITTENT -SN/FLURRY
CHANCES TONIGHT THRU FRI NIGHT.

06Z SURFACE ANALYSIS HAD THE SFC LOW DEEPENING OVER LOWER MI WITH
ARCTIC HIGH PRESSURE BUILDING INTO MT. PRESSURE GRADIENT WAS
INCREASING ACROSS THE REGION...WITH NORTH TO NORTHWEST WINDS
BRINGING IN COLDER AIR AND ERODING THE WARM LAYER ALOFT. -SN IN
THE FCST AREA BEING REPORTED AS FAR SOUTHEAST AS KOLZ/KOVS AS OF
0630Z. WV IMAGERY SHOWED A VIGOROUS SHORTWAVE LIFTING THRU THE
CENTRAL/SOUTHERN PLAINS AND TOWARD THE REGION. MAIN DEFORMATION BAND
OF SNOW WITH THIS FEATURE WAS LIFTING FROM NORTHEAST KS/SOUTHEAST
NEB AND MUCH OF THE SOUTHWEST HALF OF IA...MAKING STEADY BUT DELAYED
PROGRESS NORTHEAST TOWARD THE AREA.

NO GLARING ERRORS NOTED WITH 30.00Z MODEL INITIALIZATIONS. GIVEN THE
PASSING STRONG MID LEVEL TROUGH TODAY/TONIGHT AND FLOW TRANSITIONING
TO NORTHWEST...SOLUTIONS AS SIMILAR AS CAN BE EXPECTED FOR TODAY
THRU FRI NIGHT. DPROG/DT OF 500MB HGTS AT 30.00Z SHOWED THE SLOWER/
STRONGER MODEL RUNS OF 28.00Z AND 29.00Z VERIFIED BEST WITH THE
TROUGH OVER THE CENTRAL CONUS. ALL WERE VERY GOOD WITH THE EAST/WEST
NOAM COAST RIDGING. ECMWF WITH THE BETTER RUN-TO-RUN CONSISTENCY.
MODEL CONSENSUS TRENDS SLOWER AS THE MAIN TROUGH/ENERGY MOVES INTO
THE NORTHEAST CONUS BY 12Z THU. TREND CONTINUES A BIT STRONGER WITH
A NORTHERN STREAM SHORTWAVE TO DROPS ACROSS MN/WI ON THU.
CONSISTENCY GOOD FOR THU NIGHT THRU FRI NIGHT AS NORTHWEST FLOW
ALOFT BECOMES ESTABLISHED OVER THE REGION...BUT DIFFERENCES ON
DETAILS OF MINOR SHORTWAVES IN THIS FLOW. ECMWF WITH THE BETTER
OVERALL RUN-TO-RUN CONSISTENCY TODAY INTO FRI NIGHT. CHECK OF OBS
VS. MODEL DATA AT 06Z SHOWED A CONSENSUS LOOKED BEST AS THE SFC LOW
DEEPENED OVER LOWER MI. PER WV IMAGERY MODELS ALL LOOK REASONABLE
WITH THE SHORTWAVE ENERGY ROTATING AROUND THE EAST SIDE OF THE
TROUGH AND TOWARD THE UPPER MIDWEST. ECMWF/NAM LOOKED BEST WITH THE
00-06Z PRECIP ACROSS THE MID/UPPER MS VALLEY. FAVORED A MODEL/
ENSEMBLE CONSENSUS WEIGHTED TOWARD THE ECMWF WITH ITS BETTER RUN-TO-
RUN CONSISTENCY AND PERFORMANCE WITH THE 00-06Z MID-CONUS PRECIP.
SHORT TERM FCST CONFIDENCE AVERAGE TO GOOD THIS CYCLE.

IN THE SHORT TERM...TODAY IS ALREADY PROBLEMATIC DUE TO AN EASTWARD
SHIFT OF THE MODEL CONSENSUS WITH QPF /SNOW/ PRODUCTION AND
INHERITED HEADLINES. DEFORMATION BAND OF SNOW ASSOCIATED WITH THE
STRONG MID LEVEL SHORTWAVE AND MDT/STRONG 850-500MB FN CONVERGENCE
STILL TRANSLATES ACROSS THE AREA TODAY. WITH ALL THE MID MS/LOWER
OH VALLEY CONVECTION DRIVING THE TROUGH/COLD FRONT EAST...AND
INTERCEPTING A LOT OF THE MOISTURE...SHORTWAVE PV ADVECTION/
DIVERGENCE ALOFT AND LOWER/MID LEVEL FN FORCING APPEAR TO HAVE LESS
MOISTURE TO WORK WITH THAN EARLIER MODEL RUNS INDICATED. ANOTHER
THING WORKING AGAINST HEAVIER QPF/SNOW THRU TODAY IS FASTER MOVEMENT
OF THE FORCING ACROSS THE AREA. WHAT LOOKED LIKE IT MIGHT BE 18HRS
OF FORCING/LIFT NOW LOOKS MORE LIKE 9-12HRS AS THE SHORTWAVE PASSES.
ALL THIS TRENDS TOWARD LESS SNOW FOR THE AREA EARLY THIS MORNING AND
TODAY.

HAVE ALREADY CANCELED ADVISORIES AND REDUCED WINTER STORM WARNING TO
ADVISORY ALONG/NORTHWEST OF A NEW HAMPTON IA-LA CROSSE-BLACK RIVER
FALLS LINE. WARNING CONTINUES TO LOOK GOOD ACROSS THE SOUTHEAST 1/3
TO HALF OF THE FCST AREA. MAY NOT QUITE GET 6 INCHES OF SNOW...BUT
BLOWING/DRIFTING LATER AS NORTHWEST GRADIENT WINDS CONTINUE TO
INCREASE ALONG/SOUTHEAST OF A KOLZ-VIROQUA-NECEDAH WI LINE LOOKING
TO MAKE FOR MISERABLE TRAVEL TODAY IN THOSE AREAS. SYSTEM EXITS
QUICKLY DURING THE MID/LATE AFTERNOON HOURS AND MAY BE ABLE TO
CANCEL SOME HEADLINES EARLY...ESPECIALLY WEST OF THE MS RIVER.

ARCTIC AIR POURS INTO THE AREA BEHIND THE DEPARTING LOW TONIGHT.
GRADIENT REMAINS TIGHT FOR NORTHWEST WINDS OF 10 TO 20 MPH INTO THU
MORNING AS TEMPERATURES HEAD TO NEAR AND BELOW ZERO...PRODUCING
WINDS CHILLS OF 20-25 BELOW OVER THE WEST 1/3 OF THE FCST AREA. WILL
ISSUE A WIND CHILL ADVISORY ALONG/WEST OF A WABASHA MN TO NEW
HAMPTON IA LINE FOR LATE TONIGHT/THU MORNING.

THE NORTHERN STREAM SHORTWAVE DROPS ACROSS THE AREA LATE TONIGHT/THU
WITH DEEP CYCLONIC CONVERGENCE...RATHER DEEP MOISTURE AND STEEP LOW
LEVEL LAPSE RATES ON THU. RAISED -SN CHANCES TO 60 PERCENT ACROSS
THE NORTH END OF THE FCST AREA AND 20-50 PERCENT ELSEWHERE ACROSS
THE NORTHEAST HALF OF THE FCST AREA FOR TONIGHT/THU...FOR OCCASIONAL
VERY LIGHT SNOW THAT MAY SEE SOME 1/2 INCH ACCUMULATIONS OF FLUFF.

EVEN COLDER AIRMASS SETTLES OVER THE AREA THU NIGHT WITH 925MB TEMPS
IN THE -20C TO -26C RANGE...DEPENDING ON SPECIFIC MODEL DETAILS.
WINDS WILL BE LIGHTER...MORE IN THE 5-10MPH RANGE BUT TEMPS AROUND
12Z FRIDAY LOOKING TO BE IN THE -8F TO -16F RANGE. WIND CHILLS THU
NIGHT/FRI MORNING HEADED INTO THE -20 TO -35 RANGE AND ANOTHER WIND
CHILL ADVISORY WILL BE NEEDED. WILL NOT COMPLICATE HEADLINE PICTURE
ANY FURTHER AND LEAVE THIS ONE TO BE ISSUED LATER.

DETAILS DIFFER AMONG THE MODELS BY FRI/FRI NIGHT BUT ALL DROP
ANOTHER STRONGER SHORTWAVE SOUTHEAST ACROSS THE GREAT LAKES...ALONG
WITH A WEAKER ONE SOUTHEAST ACROSS THE NORTHERN PLAINS. THIS SETS
OFF A ROUND OF MDT TO STRONG 925-700MB WARM ADVECTION LIFT ACROSS
THE REGION. THE QUESTION IS HOW MUCH MOISTURE WILL THERE BE AND
WHERE WILL THE STRONGER OF THE ISENTROPIC LIFT/VERTICAL MOTION
OCCUR. MODEL CONSENSUS KEEPS THE SFC-850MB LAYER DRY FRI SO WILL
LEAVE FRI DRY FOR NOW. SMALL -SN CHANCE FRI NIGHT REASONABLE WITH
BETTER INDICATION FOR SFC TO AT LEAST 800MB SATURATION BEING PUSHED
INTO THE COLD AIRMASS OVER THE AREA.

FAVORING A MODEL/ENSEMBLE CONSENSUS LEAD BY THE ECMWF...USED A BLEND
OF THE NUMERICAL TEMPERATURE GUIDANCE WEIGHTED TOWARD THE ECMWF FOR
HIGHS/LOWS TODAY THRU FRI NIGHT. TEMPS TO FALL TODAY AS THE ARCTIC
AIRMASS SPREADS IN...WITH HIGHS AROUND 12-13Z THIS MORNING. FOR THU
NIGHT LOWS...IF WINDS BECOME LIGHT/VARIABLE CALM OVER THE FRESH SNOW
COVER IN THE -20C TO -26C 925MB AIRMASS...LOWS IN SOME OF THE
SHELTERED VALLEYS/NORMALLY COLDER LOW LAYING AREAS COULD DROP INTO
THE -20F TO -30F RANGE.

.LONG TERM...SATURDAY THROUGH TUESDAY...
353 AM CST WED JAN 30 2013

NOT A LOT OF TIME SPENT IN THE DAY 4-7 PERIOD AGAIN THIS MORNING
WITH ALL THE ISSUES AND HEADLINES IN THE SHORT TERM. 30.00Z MEDIUM
RANGE MODELS IN RATHER GOOD AGREEMENT SAT FOR YET ANOTHER STRONGER
NORTHWEST FLOW SHORTWAVE TO DROP SOUTHEAST ACROSS THE REGION...THIS
ONE ACROSS MN/WI...OVER WHAT WILL STILL BE A RATHER COLD AND EASIER
TO SATURATE AIRMASS/COLUMN. SMALL -SN CHANCE SAT LOOKS REASONABLE.
GOOD CONSENSUS FOR THE FLOW TO FLATTEN A BIT/BECOME MORE WEST-
NORTHWEST SUN INTO MON WITH YET ANOTHER SHORTWAVE TO DROP SOUTHEAST
ACROSS THE REGION. MAY YET NEED SMALL -SN CHANCES OVER MUCH OF THE
FCST AREA SUN DEPENDING ON DETAILS/WHERE THIS WAVE AND ATTENDANT SFC
LOW TRACK. AREA REMAINS UNDER NORTHWEST FLOW ALOFT MON/TUE BUT
MODELS DIVERGING WITH TIMING OF UNIDENTIFIABLE SHORTWAVES THRU THE
FLOW. FCST CONFIDENCE IN THE LONG TERM LOOKS AVERAGE. GIVEN THIS AND
NOT A LOT TIME PICKING THRU THE DETAILS...LITTLE IF ANY CHANGES MADE
TO THE THE MODEL/ENSEMBLE CONSENSUS DATA IN THE DAY 4-7 FCST GRIDS.

.AVIATION...THROUGH 06Z THURSDAY
1105 PM CST TUE JAN 29 2013

THE SURFACE LOW HAS MOVED SLOWLY OUT OF NORTHWEST ARKANSAS INTO
SOUTH CENTRAL MISSOURI THIS EVENING. THIS HAS RESULTED IN A SLOW
NORTHWARD PUSH OF THE SNOW FROM SOUTHWEST IOWA INTO CENTRAL IOWA.
THE 30.00Z NAM AND 30.02Z HRRR CONTINUE TO HAVE A GOOD HANDLE ON
HOW THE PRECIPITATION HAS BEEN EVOLVING THIS EVENING WITH BOTH
MODELS SUGGESTING THAT KLSE HAS A BETTER CHANCE OF GETTING INTO
THE PRECIPITATION THAN KRST DOES. WITH THE NORTHEAST MOVEMENT OF
THE SNOW...IT IS EXPECTED TO START MOVING INTO KLSE LATE TONIGHT
AND KRST AROUND 12Z WITH VISIBILITIES GOING DOWN TO MVFR. AS THE
MODERATE TO STRONG FRONTOGENESIS IN THE 750-500 MB LAYER COMES
ACROSS WEDNESDAY MORNING...THE SNOW SHOULD INTENSIFY BUT WITH THE
BEST ISENTROPIC UP GLIDE ON THE 290K SURFACE REMAINING SOUTHEAST
OF BOTH TAF SITES...NOT EXPECTING THE HEAVIEST BAND OF SNOW TO
IMPACT EITHER TAF SITE. BOTH SITES SHOULD STILL SEE IFR CONDITIONS
BUT THE VISIBILITY SHOULD BE LOWER AT KLSE. KRST WILL SEE
IMPROVEMENT STARTING ALREADY LATE WEDNESDAY MORNING AND IN THE EARLY
AFTERNOON OR KLSE AS CONDITIONS GO BACK TO MVFR. SOME FLURRIES
EXPECTED TO HANG ON DURING THE AFTERNOON WITH VFR VISIBILITY BUT
LOOK FOR THE CEILINGS TO REMAIN MVFR FOR THE REMAINDER OF THE
PERIOD. THE TIGHT GRADIENT AROUND THE SURFACE LOW WILL PRODUCE
SUSTAINED NORTH TO NORTHWEST WINDS OF 15 TO 20 KNOTS WITH GUSTS OF
25 TO 30. THE NAM BUFKIT SOUNDINGS SUGGEST THE LOW LEVEL LAPSE RATES
WILL REMAIN STEEP ENOUGH TO KEEP THE GUSTS GOING AFTER SUNSET
WEDNESDAY EVENING.

.ARX WATCHES/WARNINGS/ADVISORIES...
353 AM CST WED JAN 30 2013

WI...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ029-
033-034-041.

WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR
WIZ042>044-053>055-061.

MN...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ088-
095-096.

WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST THURSDAY
FOR MNZ079-086-087-094-095.

IA...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR IAZ009-
010-018-019.

WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST THURSDAY
FOR IAZ008-009-018-019.

WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR IAZ011-
029-030.

SHORT TERM...RRS
LONG TERM....RRS
AVIATION.....04

AREA FORECAST DISCUSSION

NWS TAUNTON MA

1005 AM EST WED JAN 30 2013

.SYNOPSIS...
A WARM FRONT WILL PUSH NORTH OF THE REGION THIS MORNING...BRINGING
MILDER CONDITIONS. WINDS WILL BECOME VERY WINDY LATE THIS
AFTERNOON AND TONIGHT AHEAD OF A STRONG COLD FRONT. HEAVY SHOWERS
AND ISOLATED THUNDERSTORMS ARE POSSIBLE. THE FRONT WILL PUSH
ACROSS THE REGION THURSDAY MORNING...BRINGING WITH MORE WINDY
CONDITIONS AND COLDER TEMPERATURES. A COUPLE OF RELATIVELY FAST
MOVING SYSTEMS MAY PRODUCE LIGHT SNOW ON SUNDAY AND AGAIN ON
TUESDAY OF NEXT WEEK.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

1005 AM UPDATE...

DENSE FOG CONTINUES TO AFFECT INTERIOR SOUTHERN NEW ENGLAND AS OF
MID TO LATE MORNING. BASED ON CURRENT OBSERVATIONS AND TRENDS WILL
LIKELY HAVE TO EXTEND IT INTO THE AFTERNOON WITH UNSEASONABLY HIGH
DEWPOINT OVER RUNNING TEMPS IN THE LOWER TO MIDDLE
30S. MEANWHILE...ACROSS THE COASTAL PLAIN THE SURFACE HAS MIXED OUT
AND TEMPS HAVE SOARED INTO THE 50S. IN FACT...A FEW LOCATIONS
MAY TAKE A RUN AT 60 LATER THIS AFTERNOON. NOW WE ARE CONFIDENT THAT
TEMPERATURES WILL EVENTUALLY REACH INTO THE 50S ACROSS THE
INTERIOR...BUT ITS UNCERTAIN EXACTLY HOW FAST THAT WILL OCCUR. IN
SOME LOCATIONS...PARTICULARLY ACROSS SOUTHERN NH THIS MAY NOT HAPPEN
UNTIL EARLY EVENING. WE FOLLOWED THE HRRR MODEL TEMPS WHICH SEEM TO
HAVE A GOOD HANDLE ON THE SITUATION.

MAINLY DRY WEATHER EXPECTED FOR THE NEXT FEW HOURS...BUT SOME
SCATTERED SHOWERS MAY WORK INTO THE INTERIOR LATER IN THE AFTERNOON
BUT CERTAINLY NOT EXPECTING A WASHOUT. BEST DYNAMICS WILL REMAIN
WELL TO OUR WEST FOR THE REMAINDER OF THE AFTERNOON.

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
TONIGHT...
SHOWERS WILL MOVE IN AHEAD OF APPROACHING FRONT...SOME OF WHICH
MAY PRODUCE HEAVY DOWNPOURS. GOOD INSTABILITY CONTINUES AS K
INDICES RISE TO THE MID 30S...SO HAVE MENTIONED ISOLD
THUNDERSTORMS THROUGH MOST OF THE NIGHT. BIGGEST EFFECTS WILL BE
DUE TO STRONG WINDS WITH TIGHT PRES GRADIENT. H85 AND H925 JETS ON
ORDER OF 70-80 KT WILL CROSS THE REGION AND...WITH MILD TEMPS
REMAINING...EXPECT SOME VERY STRONG GUSTS TO MIX DOWN ESPECIALLY
WITH ANY CONVECTION THAT DEVELOPS. LOOKS LIKE THE BIGGEST THREAT
FOR THE STRONGEST GUSTS WILL BE ACROSS SOUTHEASTERN SECTIONS.

WITH THE THREAT OF DAMAGING WINDS ACROSS RI/SE MA...HAVE ISSUED
HIGH WIND WARNING FOR THOSE AREAS. WOULD NOT BE SURPRISED TO SEE
GUSTS ON ORDER OF 50-55 MPH...MAYBE EVEN HIGHER. ELSEWHERE...HAVE
KEPT THE HIGH WIND WATCH IN PLACE...THOUGH COULD BE CONVERTING TO
EITHER A WIND ADVISORY OR WARNING DURING THE DAY SHIFT.

EXPECT TEMPS TO ACTUALLY TOP OFF LATE TONIGHT OR EVEN INTO THE WEE
HOURS OF THURSDAY. A FEW SPOTS MAY ACTUALLY SEE 60 DEGREES...
LIKELY ACROSS EASTERN AREAS.

SHORT RANGE MODELS IN GOOD AGREEMENT THAT THE COLD FRONT WILL
MOVE INTO WESTERN AREAS AFTER 06Z...REACHING THE E COAST AROUND
12Z OR SO. COLDER AIR WILL START TO SPILL INTO WESTERN AREAS BY
AROUND SUNRISE.

.LONG TERM /THURSDAY THROUGH TUESDAY/...
HIGHLIGHTS...

* WIND ADVISORY STRENGTH WINDS POSSIBLE BEHIND FRONT THU
* COLDER THU NIGHT INTO THE WEEKEND
* CHANCE OF SNOW...PROBABLY LIGHT...ON SUN AND AGAIN TUE

OVERALL PICTURE...STRONG COLD FRONT MOVES OFFSHORE THU. BROAD
UPPER LONG WAVE TROF DOMINATES ACROSS EASTERN N AMERICA IN THE
LONGER TERM PERIOD WITH SERIES OF QUICK MOVING SHORT WAVE TROFS
PASSING THROUGH. SURFACE REFLECTION OF THESE SHORTWAVES ARE
CLIPPER SYSTEMS. LOOKS LIKE ONE PASS THRU ON SUN AND ANOTHER TUE.
SOME UNCERTAINTY WHETHER THE SURFACE CENTERS WILL PASS JUST N OR
JUST S OF SOUTHERN NEW ENGLAND. STEADIER AND SOMEWHAT HIGHER QPF
EXPECTED NORTH OF THE CENTER...AND SURFACE LOWS PASSING S OF
SOUTHERN NEW ENGLAND CAN ADD A LITTLE MORE QPF DUE TO SOME ATLC
INFLOW. AT THIS TIME...NONE OF THESE SYSTEMS LOOK ESPECIALLY
POTENT WITH ANY SNOW ACCUM LOOKING TO BE UNDER ADVISORY
THRESHOLDS. THIS PICTURE COULD CHANGE AS WE GET CLOSER TO THESE
EVENTS.

DAY BY DAY PICTURE...
THU...DEEP MIXING BEHIND COLD FRONT MAY BE ENOUGH TO SUPPORT WIND
ADVISORIES OVER PORTIONS OF THE AREA DURING THE LATE MORNING AND
AFTERNOON. NO HEADLINES NOW DUE TO THE PREFRONTAL HIGH WIND
WARNINGS/WATCHES. TEMPS MAY HOLD STEADY FOR A WHILE DURING THE
MORNING AND START A STEADY SLIDE DURING THE AFTERNOON INTO THU
NIGHT DUE TO STRONG COLD AIR ADVECTION.

FRI...ALL MODELS INDICATE A FAIRLY WELL DEFINED SHORT WAVE TROF
PASSAGE ON FRI. MOISTURE IS LIMITED BUT SHARPNESS OF THE TROF
SUGGESTS MENTION OF SCT FLURRIES.

SAT...LOOKS DRY WITH BELOW NORMAL TEMPS.

SUN...SHORT WAVE TROF WITH BAGGINESS IN SFC PRES FIELD DEPICTED BY
MEDIUM RANGE MODELS SUGGESTS A CHANCE OF LIGHT SNOW. ALTHOUGH THE
GFS SHOWS A TAD MORE QPF...THE ECMWF ACTUALLY SHOWS A SOMEWHAT
SHARPER SHORT WAVE TROF WITH A NEGATIVE TILT HINT. PUT POPS AT 50
PERCENT FOR MOST OF AREA FOR SUN.

MON-TUE...MON LOOKS DRY BEFORE ANOTHER SHORT WAVE UPPER TROF AND
SFC CLIPPER LOW PASSES THRU WITH ANOTHER CHANCE OF A PERIOD OF
LIGHT SNOW. GFS ENSEMBLES SEEM TO FAVOR A SLIGHTLY MORE SOUTHERLY
TRACK WITH THIS LOW CENTER COMPARED WITH THE ONE ON SUN BUT TOO
FAR OUT FOR MUCH CONFIDENCE.

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

OVERVIEW...MODERATE TO HIGH CONFIDENCE ON TRENDS BUT LOW CONFIDENCE
ON TIMING.

REST OF TODAY...IFR TO LOW END MVFR CONDITIONS WILL PERSIST ON THE COASTAL
PLAIN. MAINLY LIFR CONDITIONS WILL CONTINUE AT LEAST INTO MID
AFTERNOON ACROSS THE INTERIOR AS A RESULT OF DENSE FOG. CONDITIONS
SHOULD EVENTUALLY IMPROVE TO IFR...BUT THAT MAY NOT OCCUR UNTIL
LATER THIS AFTERNOON/EARLY EVENING.

LOW LEVEL JET MOVES IN WITH S-SW WINDS UP TO 50-60 KT DURING THIS
AFTERNOON. EXPECT GUSTS UP TO 30-40 KT AT THE SURFACE MAINLY
ACROSS RI/SE MA AND HIGHER TERRAIN.

TONIGHT...MVFR VSBYS/IFR-LIFR CIGS PREVALENT AS STRONG COLD FRONT
MOVES THROUGH. LLWS CONTINUES...APPROACHING 75 KT AT 2KFT ALONG
THE S COAST...CAPE COD AND THE ISLANDS...POSSIBLY APPROACHING 80
KT ACROSS OUTER CAPE COD AND NANTUCKET AFTER 09Z THU. EXPECT
SURFACE GUSTS OF 40-50 KT ACROSS MOST AREAS...POSSIBLY UP TO 55 KT
ALONG S COAST. ISOLD TSTMS POSSIBLE ALONG/AHEAD OF COLD FRONT.

CIGS/VSBYS MAY START TO IMPROVE TO VFR ACROSS CT VALLEY AFTER
09Z...THOUGH LOWER CONFIDENCE ON TIMING.

KBOS TAF...MODERATE CONFIDENCE. IFR TO LOW END MVFR CONTINUES
THROUGH THE AFTERNOON. SW LLWS EXPECTED THIS AFTERNOON/TONIGHT. SW
SURFACE WIND GUSTS UP TO 40-50 KT FROM 03Z-11Z.

KBDL TAF...MODERATE CONFIDENCE. LIFR CONDITIONS IN DENSE FOG SHOULD
EVENTUALLY IMPROVE TO IFR SOMETIME THIS AFTERNOON. S-SW LLWS
EXPECTED THROUGH TONIGHT. S-SW WIND GUSTS UP TO 40-50 KT FROM
04Z-10Z.

OUTLOOK...THURSDAY THROUGH SUNDAY...

HIGH CONFIDENCE OF VFR CONDITIONS BY LATE MORNING THU AND LASTING
THRU SAT. LOW TO MODERATE CONFIDENCE OF MVFR CIGS/VSBYS WITH
POCKETS OF IFR IN SNOW SUN.

SFC WIND GUSTS 35 TO 45 KT LIKELY BEHIND COLD FRONT THU AFTERNOON
AND CONTINUING TO GUST TO AROUND 25 KT THU NIGHT AND FRI.

.MARINE...
MODERATE TO HIGH CONFIDENCE THROUGH TONIGHT.

TODAY...S-SW WINDS WILL PICK UP DURING THE DAY...POSSIBLY REACHING
GALE FORCE ON THE OPEN WATERS THIS AFTERNOON. SEAS WILL ALSO
BUILD...UP TO 8 FT ON THE SOUTHERN WATERS BY EVENING.

TONIGHT...EXPECT STRONGEST S-SW WINDS TO MOVE ACROSS THE WATERS
DURING THIS TIMEFRAME. MAY SEE WIND GUSTS UP TO 50-55 KT OVER THE
OPEN WATERS SO HAVE ISSUED STORM WARNINGS. WINDS MAY NOT QUITE
REACH STORM FORCE ON BOSTON HARBOR OR NARRAGANSETT BAY...SO ISSUED
GALES FOR THOSE WATERS. SEAS MAY REACH 15-18 FT ON THE SOUTHERN
OUTER WATERS LATE TONIGHT.

OUTLOOK...THURSDAY THROUGH SUNDAY...

MODERATE TO HIGH CONFIDENCE THRU SATURDAY. MODERATE CONFIDENCE FOR
SUNDAY. STORM FORCE WINDS AHEAD OF FRONT AND THEN STRONG GALE
LIKELY BEHIND THE FRONT FROM W TO NW WITH GUSTS 40 TO 45 KT THU
AFTERNOON AND EVENING. WINDS GRADUALLY DIMINISHING LATE THU NIGHT
INTO FRI BUT MAY STILL SEE GUSTS BETWEEN 25 AND 30 KT ON FRI.

WINDS SHOULD BE UNDER SMALL CRAFT ADVISORY THRESHOLDS ON SAT BUT
POSSIBLY REACHING TO NEAR GALE FORCE IN GUSTS OVER OUTER S AND SE
COASTAL WATERS SUN AFTERNOON FROM W OR WNW AS DEPARTING LOW OVER
THE GULF OF MAINE INTENSIFIES.

AREAS OF FREEZING SPRAY POSSIBLE LATE THU NIGHT THRU SAT.

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...DENSE FOG ADVISORY UNTIL NOON EST TODAY FOR CTZ002>004.
HIGH WIND WATCH FROM 6 PM EST THIS EVENING THROUGH THURSDAY
MORNING FOR CTZ002>004.
MA...DENSE FOG ADVISORY UNTIL NOON EST TODAY FOR MAZ002>005-008>012-
026.
HIGH WIND WATCH FROM 6 PM EST THIS EVENING THROUGH THURSDAY
MORNING FOR MAZ002>016-026.
HIGH WIND WARNING FROM 9 PM THIS EVENING TO 8 AM EST THURSDAY
FOR MAZ017>024.
NH...DENSE FOG ADVISORY UNTIL NOON EST TODAY FOR NHZ011-012-015.
HIGH WIND WATCH FROM 6 PM EST THIS EVENING THROUGH THURSDAY
MORNING FOR NHZ011-012-015.
RI...DENSE FOG ADVISORY UNTIL NOON EST TODAY FOR RIZ001.
HIGH WIND WARNING FROM 9 PM THIS EVENING TO 8 AM EST THURSDAY
FOR RIZ001>008.
MARINE...STORM WARNING FROM 6 PM THIS EVENING TO 11 AM EST THURSDAY FOR
ANZ231>235-237-250-251-254>256.
GALE WARNING FROM 6 PM THIS EVENING TO 11 AM EST THURSDAY FOR
ANZ230-236.

$$
SYNOPSIS...EVT/THOMPSON
NEAR TERM...FRANK
SHORT TERM...EVT
LONG TERM...THOMPSON
AVIATION...FRANK/EVT/THOMPSON
MARINE...EVT/THOMPSON

AREA FORECAST DISCUSSION

NWS JACKSONVILLE FL

1132 AM EST WED JAN 30 2013

...WINDY WITH RECORD WARMTH THIS AFTERNOON...
...SLIGHT RISK OF SEVERE THUNDERSTORMS WITH DAMAGING WIND GUSTS IN
SOUTHEAST GEORGIA THIS EVENING...

.CURRENTLY...
MORNING SURFACE ANALYSIS DEPICTS A STRONG COLD FRONT EXTENDING
FROM THE OHIO VALLEY SOUTHWARD TO THE CENTRAL GULF COAST AND THE
WESTERN GULF OF MEXICO. WAVES OF LOW PRESSURE ARE PROGRESSING
NORTHEASTWARD ALONG THIS FRONT...AND AN EXTENSIVE SQUALL LINE IS
FOUND JUST AHEAD OF THE FRONT. THIS SQUALL LINE IS ENTERING
NORTHWEST GEORGIA AND TRAILS SOUTH-SOUTHWESTWARD THROUGH ALABAMA
AND SOUTHERN MISSISSIPPI. THIS SQUALL LINE HAS PRODUCED NUMEROUS
REPORTS OF DAMAGING WINDS AND ISOLATED TORNADOES DURING THE PAST
24 HOURS. ALOFT...DEEP-LAYERED RIDGING WAS SITUATED OVER THE
WESTERN ATLANTIC...WHILE A SHARP TROUGH OVER THE MISSOURI VALLEY
WAS IN THE PROCESS OF BECOMING NEGATIVELY TILTED. THIS WEATHER
PATTERN HAS BROUGHT A STRONG VEERING WIND PROFILE INTO OUR REGION.
THE MORNING SOUNDING AT JACKSONVILLE REVEALED 35 KNOT WINDS AT
1000 FEET. SUSTAINED SOUTHERLY SURFACE WIND SPEEDS ARE ALREADY
EXCEEDING 20 KNOTS IN SOME LOCATIONS...AND WE MAY NEED TO EXTEND
THE WIND ADVISORY TO COVER ALL OF OUR COUNTIES THIS AFTERNOON AS
THE GRADIENT TIGHTENS FURTHER. NEAR ALL-TIME JANUARY RECORDS ARE
POSSIBLE THIS AFTERNOON AT JACKSONVILLE (84 DEGREES...LAST REACHED
IN 1982) AND ALMA (83 DEGREES...REACHED YESTERDAY).

THE STORM PREDICTION CENTER HAS MAINTAINED A SLIGHT RISK FOR
SEVERE THUNDERSTORMS DUE TO DAMAGING WIND GUSTS FOR OUR SOUTHEAST
GA COUNTIES. LATEST RUC GUIDANCE SUGGESTS THAT A FEW SHOWERS WILL
DEVELOP OVER THE NORTHEAST GULF THIS AFTERNOON...WHICH WILL MOVE
QUICKLY INTO INTERIOR SE GA. SLOWED THE SOUTHEASTWARD PROGRESSION
OF POPS LATE THIS AFTERNOON/EVENING DUE TO LATEST TRENDS IN THE
SHORT TERM GUIDANCE. MODEL SOUNDINGS SUGGEST A UNI-DIRECTIONAL
SHEAR VECTOR BY THE TIME THE SQUALL LINE ARRIVES IN SE GA AND THE
FL BIG BEND AROUND SUNSET. INSTABILITY WILL ALMOST NEGLIGIBLE PER
MODEL SOUNDINGS...AND THUS NOT EXPECTING A WIDESPREAD SEVERE
WEATHER EVENT...AS DYNAMICS WILL ALSO BE LIFTING NORTHWARD AND
AWAY FROM OUR REGION AS THE SQUALL LINE MOVES THROUGH. RAINFALL
AMOUNTS OF ONE QUARTER TO ONE HALF INCH ARE EXPECTED WITH THIS
EVENT. RAIN SHOULD END OVER OUR SOUTHERN COUNTIES BY 09Z.

.AVIATION...
VFR CONDITIONS WILL PREVAIL THROUGH AT LEAST 02Z. SOUTHERLY
SURFACE WINDS WILL REMAIN SUSTAINED AT 15 TO 25 KTS AT ALL TAF
SITES THROUGH 00Z. SURFACE GUSTS UP TO 35 KNOTS ARE EXPECTED AFTER
16Z. SURFACE WINDS WILL BECOME SOUTHWESTERLY TOWARDS 00Z AND THEN
WESTERLY AFTER 06Z FOLLOWING THE PASSAGE OF A COLD FRONT. SHOWERS
AND ISOLATED EMBEDDED THUNDERSTORMS WILL PROGRESS ACROSS THE
TERMINALS FROM 02Z-06Z...WITH A PERIOD OF SUB-VFR CONDITIONS
LIKELY DURING THIS TIME PERIOD. A FEW LINGERING SHOWERS ARE
POSSIBLE THROUGH 09Z. SOUTH TO SOUTHWEST WINDS OF 25 TO 35 KTS
FROM 2000 TO 10000 FEET WILL INCREASE TO 40 TO 55 KTS TOWARDS 00Z.

.MARINE...
SMALL CRAFT ADVISORIES ARE POSTED THROUGH THURSDAY...WITH SOUTH
WINDS INCREASING TO 20 TO 30 KNOTS WITH OCCASIONAL GUSTS TO GALE
FORCE. MORE GALE FORCE GUSTS POSSIBLE TONIGHT AS SQUALL LINE
MOVES OFFSHORE...THEN SHIFT TO W/NW LATE TONIGHT WITH STRONG COLD
AIR PUSH BEHIND THE FRONT THURSDAY MORNING WITH A SUBSIDING TREND
FOR THU AFTERNOON. EXPECTING GALE FORCE GUSTS TO BE PREVALENT
FOR A SHORT TIME DURING THE PASSAGE OF THE SQUALL LINE...SO WE
WILL NOT ISSUE A GALE WARNING AT THIS TIME. HIGH PRESSURE WILL
THEN BUILD IN THROUGH THE WEEKEND...WITH HEADLINES NOT ANTICIPATED
AT THIS TIME.

RIP CURRENTS: LOW RISK WITH SIDE-SHORE FLOW TODAY AND OFFSHORE FLOW
ON THURSDAY.

.FIRE WX...
STRONG SOUTH WINDS TODAY WILL PUSH DISPERSION INDICES WELL ABOVE
CRITICAL LEVELS CLOSE TO 100...BUT RH LEVELS WILL REMAIN GENERALLY
ABOVE 40 PERCENT. FOR THURS...COOL AND DRY AIRMASS WILL PUSH IN ON
NORTHWEST WINDS AND EXPECT CRITICAL RH VALUES DOWN AROUND 25
PERCENT...BUT SUSTAINED WINDS MAY REMAIN JUST BELOW 15 MPH. ERC
VALUES MAY ALSO DECREASE DEPENDING UPON AMOUNT OF RAINFALL
TONIGHT. WILL CONSIDER A FIRE WEATHER WATCH DURING THE AFTERNOON
FORECAST PACKAGE GIVEN THESE FACTORS.

.PRELIMINARY POINT TEMPS/POPS...
AMG 81 45 59 33 / 50 60 10 0
SSI 79 48 59 39 / 20 60 10 0
JAX 84 48 61 33 / 20 70 10 0
SGJ 82 53 61 39 / 20 60 10 0
GNV 82 51 62 33 / 20 70 10 0
OCF 84 53 63 34 / 20 60 10 0

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...WIND ADVISORY UNTIL 8 PM EST THIS EVENING FOR ALACHUA-BAKER-
BRADFORD-COLUMBIA-GILCHRIST-HAMILTON-SUWANNEE-UNION.

LAKE WIND ADVISORY UNTIL 8 PM EST THIS EVENING FOR CLAY-DUVAL-
FLAGLER-MARION-NASSAU-PUTNAM-ST JOHNS.

GA...WIND ADVISORY UNTIL 8 PM EST THIS EVENING FOR APPLING-ATKINSON-
BACON-BRANTLEY-CHARLTON-CLINCH-COFFEE-ECHOLS-JEFF DAVIS-
PIERCE-WARE-WAYNE.

LAKE WIND ADVISORY UNTIL 8 PM EST THIS EVENING FOR COASTAL
CAMDEN-COASTAL GLYNN-INLAND CAMDEN-INLAND GLYNN.

AM...SMALL CRAFT ADVISORY UNTIL 3 PM EST THURSDAY FOR ALTAMAHA SOUND
GA TO FERNANDINA BEACH FL 20 NM TO 60 NM OFFSHORE-
FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM OFFSHORE-
ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM OFFSHORE.

SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 AM EST THURSDAY FOR
ALTAMAHA SOUND GA TO FERNANDINA BEACH FL OUT 20 NM-
FERNANDINA BEACH TO ST AUGUSTINE FL OUT 20 NM-ST AUGUSTINE
TO FLAGLER BEACH FL OUT 20 NM.

NELSON/ENYEDI/CHASE

AREA FORECAST DISCUSSION...UPDATED

NWS PEACHTREE CITY GA

108 PM EST WED JAN 30 2013

.PREV DISCUSSION... /ISSUED 1043 AM EST WED JAN 30 2013/

UPDATE...
HAVE MADE UPDATES TO THE WEATHER AND POP GRIDS...AND SLOWED DOWN
THE CURRENT TIMING OF THE SQUALL LINE. WE ARE STARTING TO SEE
ISOLATED SUPERCELLS OUT FRONT OF THE MAIN LINE. THERE IS AN
ESPECIALLY STRONG TO SEVERE CELL IN EAST CENTRAL ALABAMA. WE ARE
STILL ON TRACK FOR SEVERE THUNDERSTORMS TODAY THROUGH THE AREA.
THE MAIN LINE IS EXPECTED TO PUSH THROUGH THE STATE WITH STRONG
WINDS BEING THE MAIN THREAT. THERE IS ALSO A RISK OF TORNADOES
WITH THESE STORMS...ESPECIALLY ANY SUPERCELLS OUT IN FRONT OF THE
LINE. DID ADJUST THE TEMPERATURES DOWN A FEW DEGREES AS THEY WERE
FORECAST WARMER THAN WHAT WAS GOING ON.

NO OTHER UPDATES ARE EXPECTED AT THIS TIME.

ARG

PREV DISCUSSION... /ISSUED 647 AM EST WED JAN 30 2013/

PREV DISCUSSION... /ISSUED 621 AM EST WED JAN 30 2013/

UPDATE...
SECOND UPDATE TO INCLUDE EXPANDED TORNADO WATCH 17 AREA IN THE
FFC WATCHES/WARNINGS/ADVISORIES SECTION BELOW.

BELANGER

PREV DISCUSSION... /ISSUED 410 AM EST WED JAN 30 2013/

SNELSON

BELANGER

SNELSON

.AVIATION...
18Z UPDATE...
MVFR CONDITIONS EXPECTED THROUGH THE DAY TODAY AND THROUGH EARLY
EVENING ACROSS MOST OF THE AREA. AFTER THE MOISTURE CLEARS
OUT...EXPECT VFR CONDITIONS. MAIN CONCERN TODAY IS THE TIMING OF
THE SQUALL LINE MOVING THROUGH THE AREA. HAVE ADJUSTED THE TAFS
FOR BEST TIMING...POTENTIAL EXISTS FOR SEVERE WEATHER WITH THESE
STORMS INCLUDING DAMAGING WIND AND POSSIBLE TORNADOES.

//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE ON TIMING...HIGH CONFIDENCE ON ALL OTHER ELEMENTS.

ARG

TORNADO WATCH UNTIL 4 PM EST THIS AFTERNOON FOR THE FOLLOWING
ZONES: BALDWIN...BANKS...BARROW...BARTOW...BIBB...BLECKLEY...
BUTTS...CARROLL...CATOOSA...CHATTAHOOCHEE...CHATTOOGA...
CHEROKEE...CLARKE...CLAYTON...COBB...COWETA...CRAWFORD...DADE...
DAWSON...DEKALB...DOOLY...DOUGLAS...FANNIN...FAYETTE...FLOYD...
FORSYTH...GILMER...GORDON...GREENE...GWINNETT...HALL...HANCOCK...
HARALSON...HARRIS...HEARD...HENRY...HOUSTON...JACKSON...JASPER...
JONES...LAMAR...LUMPKIN...MACON...MADISON...MARION...
MERIWETHER...MONROE...MORGAN...MURRAY...MUSCOGEE...NEWTON...
NORTH FULTON...OCONEE...OGLETHORPE...PAULDING...PEACH...
PICKENS...PIKE...POLK...PULASKI...PUTNAM...ROCKDALE...SCHLEY...
SOUTH FULTON...SPALDING...STEWART...SUMTER...TALBOT...
TALIAFERRO...TAYLOR...TOWNS...TROUP...TWIGGS...UNION...UPSON...
WALKER...WALTON...WEBSTER...WHITE...WHITFIELD...WILKES...
WILKINSON.

HIGH WIND WARNING UNTIL 6 PM EST THIS EVENING FOR THE FOLLOWING
ZONES: DAWSON...FANNIN...GILMER...LUMPKIN...MURRAY...PICKENS...
TOWNS...UNION...WHITE.

FLOOD WATCH UNTIL MIDNIGHT EST TONIGHT FOR THE FOLLOWING ZONES:
BARTOW...CATOOSA...CHATTOOGA...CHEROKEE...COBB...DADE...DAWSON...
FANNIN...FLOYD...FORSYTH...GILMER...GORDON...HARALSON...
LUMPKIN...MURRAY...NORTH FULTON...PAULDING...PICKENS...POLK...
TOWNS...UNION...WALKER...WHITE...WHITFIELD.

WIND ADVISORY FROM 6 PM THIS EVENING TO MIDNIGHT EST TONIGHT FOR
THE FOLLOWING ZONES: DAWSON...FANNIN...GILMER...LUMPKIN...
MURRAY...PICKENS...TOWNS...UNION...WHITE.

SHORT TERM...ARG
LONG TERM....11
AVIATION...ARG

AREA FORECAST DISCUSSION...UPDATED

NWS PEACHTREE CITY GA

1043 AM EST WED JAN 30 2013

.UPDATE...
HAVE MADE UPDATES TO THE WEATHER AND POP GRIDS...AND SLOWED DOWN
THE CURRENT TIMING OF THE SQUALL LINE. WE ARE STARTING TO SEE
ISOLATED SUPERCELLS OUT FRONT OF THE MAIN LINE. THERE IS AN
ESPECIALLY STRONG TO SEVERE CELL IN EAST CENTRAL ALABAMA. WE ARE
STILL ON TRACK FOR SEVERE THUNDERSTORMS TODAY THROUGH THE AREA.
THE MAIN LINE IS EXPECTED TO PUSH THROUGH THE STATE WITH STRONG
WINDS BEING THE MAIN THREAT. THERE IS ALSO A RISK OF TORNADOES
WITH THESE STORMS...ESPECIALLY ANY SUPERCELLS OUT IN FRONT OF THE
LINE. DID ADJUST THE TEMPERATURES DOWN A FEW DEGREES AS THEY WERE
FORECAST WARMER THAN WHAT WAS GOING ON.

NO OTHER UPDATES ARE EXPECTED AT THIS TIME.

ARG

.PREV DISCUSSION... /ISSUED 647 AM EST WED JAN 30 2013/

PREV DISCUSSION... /ISSUED 621 AM EST WED JAN 30 2013/

UPDATE...
SECOND UPDATE TO INCLUDE EXPANDED TORNADO WATCH 17 AREA IN THE
FFC WATCHES/WARNINGS/ADVISORIES SECTION BELOW.

BELANGER

PREV DISCUSSION... /ISSUED 410 AM EST WED JAN 30 2013/

SNELSON

BELANGER

SNELSON

AVIATION...
12Z UPDATE...
STILL MONITORING LINE OF STRONG TSRA THAT WILL MOVE ACROSS THE
STATE TODAY AND THIS EVENING. TIMING HAS SHIFTED SLIGHTLY AND NOW
APPEARS TSRA WILL AFFECT ATL METRO 19Z-23Z. EXPECT STRONG
CROSSWIND AT E-W RUNWAY AIRPORTS TODAY...GUSTS COULD APPROACH
32KTS AT KATL. CIGS SHOULD STAY RIGHT NEAR IFR THRESHOLD AT KATL
AND REMAIN JUST ABOVE IFR ELSEWHERE. EXPECT END TO CIGS AND PRECIP
AROUND 23-00Z. STRONG WEST WINDS WILL CONTINUE OVERNIGHT AND
THURS.

//ATL CONFIDENCE...12Z UPDATE...
MEDIUM CONFIDENCE ON IFR CIGS THIS MORNING.
HIGH CONFIDENCE ON ALL OTHER ELEMENTS.

SNELSON

HIGH WIND WARNING UNTIL 6 PM EST THIS EVENING FOR THE FOLLOWING
ZONES: DAWSON...FANNIN...GILMER...LUMPKIN...MURRAY...PICKENS...
TOWNS...UNION...WHITE.

WIND ADVISORY FROM 6 PM THIS EVENING TO MIDNIGHT EST TONIGHT FOR
THE FOLLOWING ZONES: DAWSON...FANNIN...GILMER...LUMPKIN...
MURRAY...PICKENS...TOWNS...UNION...WHITE.

SHORT TERM...ARG
LONG TERM....31
AVIATION...ARG

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

209 PM CST WED JAN 30 2013

.DISCUSSION...
944 AM CST

A WEAK SECONDARY SURFACE LOW IS MAKING ITS WAY THROUGH NORTHERN IL
THIS MORNING WITH ARCTIC AIR SLOWLY SPILLING INTO WESTERN IL.
FREEPORT IL HAS ALREADY TURNED OVER TO SNOW AND GETTING REPORTS
OF RAIN MIXING WITH SLEET FROM DIXON AND ROCKFORD. AS TEMPS FALL
TODAY EXPECTING RAIN TO QUICKLY CHANGE OVER TO SNOW WITH A BRIEF
PERIOD OF SLEET/ICE PELLETS POSSIBLE. NOT EXPECTING ANY
SIGNIFICANT IMPACTS FROM SLEET/ICE PELLETS.

FOR THE WINTER WEATHER ADVISORY FOR WINNEBAGO...OGLE...AND BOONE
COUNTIES...WILL KEEP IT GOING BUT THINKING THE BEST FORCING WILL
OCCUR WHEN TEMPS ARE ABOVE FREEZING. THE UPPER LEVEL JET STREAKS
LEFT EXIT REGION IS OVER NORTHERN IL WHILE THE SPC RAP AND OTHER
GUIDANCE INDICATE A BAND OF 850 MB FRONTOGENESIS EXTENDING FROM
SOUTHERN WI THROUGH MOLINE IL. NEGATIVE EPV LIES ABOVE THE
FRONTOGENESIS WHICH WOULD SUPPORT BANDS OF LOCALLY HEAVIER
SNOWFALL. HOWEVER...THE FRONTOGENESIS IS EXPECTED TO WEAKEN
SIGNIFICANTLY THROUGH THE EARLY AFTERNOON HOURS SO THINKING THE
HEAVIEST SNOW WILL FALL THROUGH 3PM AT THE LATEST ACROSS THE
ADVISORY AREA. GIVEN THAT RAIN IS JUST TURNING OVER TO SNOW
NOW...AGREE WITH THE PREVIOUS FORECAST THAT THE ADVISORY CRITERIA
WILL PROBABLY ONLY BE MET IN ISOLATED LOCATIONS. OVERALL EXPECTING
2-4 INCHES OF SNOW IN THE ADVISORY AREA WITH LOCALLY HIGHER
AMOUNTS POSSIBLE IF A MESOSCALE BAND SETS UP OVER THE AREA.

AS TEMPS FALL THROUGH THE DAY RAIN WILL TURN OVER TO SNOW
THROUGHOUT THE DAY. ROUGH TIMINGS ARE ALL SNOW ACROSS THE ADVISORY
AREA BY NOON...NORTH OF I-55 BY 4-5 PM...CHICAGO BY 5-6 PM...AND
ALL SNOW ACROSS THE AREA BY 7-8PM. EXPECTING A WET SNOW AS IT
FIRST TURNS OVER THEN BECOMING A MORE AVERAGE SNOW LATE THIS
AFTERNOON/EVENING. ONCE AGAIN EXPECTING 2-4 INCHES IN THE
NORTHWEST CORNER OF THE CWA...1-2 INCHES NORTH OF A MENDOTA TO
WAUKEGAN LINE...AND LESS THAN AN INCH ELSEWHERE.

JEE

//PREV DISCUSSION...
353 AM CST

FORECAST CHALLENGES THIS MORNING INCLUDE POTENTIAL FOR SNOW
TODAY...CLOUD COVER AND ITS POTENTIAL IMPACTS ON TEMPS...AND CLIPPER
SYSTEM ARRIVING FRIDAY NIGHT INTO SATURDAY.

VERY TRICKY FORECAST TODAY AS COLDER AIR SPILLS INTO THE REGION AND
PORTIONS OF THE CWA POTENTIALLY GET CLIPPED BY TROWAL. HAVE OPTED TO
ISSUE A WINTER WX ADVISORY FOR MY NW 3 COUNTIES MOSTLY DUE TO MODEL
GUIDANCE AND TO MAKE A PRETTIER WATCH/WARNING/ADVISORY MAP BUT HAVE
SERIOUS DOUBTS ABOUT WHETHER IT WILL COME CLOSE TO VERIFYING BASED
ON CURRENT TRENDS IN OBSERVATIONAL DATA. WARM CONVEYOR BELT WITH
ITS MASSIVE STREAM OF RAIN CONTINUES TO SHIFT EASTWARD AND OUT OF
THE CWA EARLY THIS MORNING AND WOULD ANTICIPATE THIS TREND TO
CONTINUE AS WATER VAPOR IMAGERY SHOWS MASSIVE DEVELOPING MID LEVEL
DRY INTRUSION PUNCHING NORTHEAST INTO THE REGION. SURFACE ANALYSIS
HAS ANOTHER IN SEEMING CONGA LINE OF LOWS OVER MISSOURI STILL AT
09Z...AS THIS LOW TRANSLATES NORTHEAST INTO ILLINOIS EARLY THIS
MORNING IT WILL ACT TO SLOW THE INTRUSION OF COLD AIR AND LIKELY
DELAY THE RAIN/SNOW TRANSITION LINE FROM MAKING GOOD HEADWAY ACROSS
THE CWA UNTIL IT LIFTS OUT OF THE AREA TOWARD MIDDAY.

PROFILERS AND OBJECTIVE ANALYSIS HAVE A 120KT+ 500MB JET PUNCHING NE
INTO THE DRY INTRUSION WITH STRONG ASCENT TO THE LEFT OF THIS JET
SUPPORTING AN INTENSIFYING TROWAL THIS MORNING OVER IOWA AND
NORTHEAST MISSOURI. SUSPECT THAT THIS MORNING INTO THE EARLY
AFTERNOON AS THE DRY INTRUSION MOVES IN THAT THE PREDOMINANT PRECIP
TYPE WILL SHIFT TO DRIZZLE AND VERY LIGHT RAIN...THOUGH AS THE VORT
NEAR MCI MOVES EAST COULD SEE SOME SHOWERS REDEVELOPING IMMEDIATELY
IN ADVANCE OF THIS FEATURE. BY MIDDAY/EARLY AFTERNOON THE TROWAL
OVER IOWA/NORTHWEST MO WILL BEGIN TO TRANSLATE EAST INTO NORTHERN
ILLINOIS...BUT BY THAT POINT INSTABILITY WILL BE WEAKENING AND
BECOMING MORE FOCUSED TO OUR NORTH. ALSO...STRONG SYNOPTIC ASCENT
WILL ALSO BE SHIFTING NORTH INTO WI/MI AS THE MID LEVEL JET STREAK
PUNCH NORTH INTO THE UPPER GREAT LAKES. SUSPECT THAT THIS WILL LEAVE
OUR CWA WITH A GLANCING BLOW FROM THE DECAYING SOUTHERN FLANKS OF
WHAT WILL BE A VERY HEALTHY TROWEL THIS MORNING. COMPUTER MODELS AND
HPC GUIDANCE WOULD SUGGEST A SWATH OF 3 TO 5 INCHES OF SNOW ACROSS
OUR NORTHWEST CWA WHERE I PLACED THE ADVISORY...WHILE WHAT I`M
LOOKING AT IN OBSERVATIONAL DATA MAKE ME WONDER IF WE`LL BE ABLE TO
SQUEEZE OUT EVEN 2 INCHES. AS A COMPROMISE WILL GO WITH 2 TO 4
INCHES "POSSIBLE" WORDING AND PUT OUT AN ADVISORY TO BLEND WITH
NEIGHBORS AND ERR ON THE SIDE OF CAUTION...BUT DEFINITELY SEEING
SOME BUST POTENTIAL IN THIS FORECAST.

ACROSS THE REMAINDER OF THE CWA EXPECT DRIZZLY/SHOWERY WEATHER MUCH
OF THE DAY WITH A TRANSITION FROM RAIN TO SNOW TAKING PLACE FROM
NORTHWEST TO SOUTHEAST THIS AFTERNOON. SUPPOSE THERE COULD BE UP TO
AN INCH OF ACCUMULATION FROM THE REMNANTS OF THE TROWAL BUT NOT
LOOKING TO BE A TERRIBLY BIG DEAL. IN FACT...THE FALLING TEMPS AND
BLUSTERY WINDS WILL PROBABLY BE THE BIGGER STORY FOR MOST.

DEEP TROUGH THEN ESTABLISHES ITSELF OVER THE GREAT LAKES AND
NORTHEAST FOR THE REMAINDER OF THE WEEK. FORECAST SOUNDINGS SHOW THE
PRESENCE OF A STOUT FRONTAL INVERSION WHICH OFTEN TRAPS
MOISTURE/STRATUS THIS TIME OF YEAR...PARTICULARLY WITH THE CYCLONIC
LOW LEVEL FLOW FORECAST TO BE IN PLACE THROUGH THE REST OF THE WORK
WEEK. GUIDANCE CONTINUE TO FORECAST H8 TEMPS DROPPING TO -20C OR A
BIT COLDER BY THURSDAY AFTERNOON...SO CERTAINLY LOOKS TO BE A VERY
FORMIDABLE SHOT OF ARCTIC AIR. HOWEVER...HAVE GENERALLY TRENDED
TEMPS TOWARD THE WARMEST AVAILABLE GUIDANCE TONIGHT AS STRONG WINDS
AND STRATUS ARE EXPECTED TO HELP KEEP TEMPS UP. AS SECONDARY SURGE
OF ARCTIC AIR ARRIVES THURSDAY PROBABLY WILL SEE VERY LITTLE
RECOVERY INTO TEMPS AND WITH CLOUDS LIKELY TO LINGER THURSDAY NIGHT
AGAIN WENT WITH THE WARMER SIDE OF GUIDANCE. THE EXPECTED LACK OF
SNOW COVER WOULD ALSO TEND TO SUPPORT NOT GOING AS COLD AS MOS
NUMBERS FOR THIS TIME PERIOD.

PRECIP WISE AFTER TODAY NOT ANTICIPATING ANY BIG PRECIP THREAT UNTIL
FRIDAY NIGHT. HOWEVER...THE PRESENCE OF A STRATUS DECK WITH TEMPS
FROM THE SFC TO 700MB PROGGED TO DROP INTO THE PRIME DENDRITIC
GROWTH RANGE SUGGESTS THAT IT WILL TAKE VERY LITTLE FORCING FOR THIS
DECK TO LEAK FLURRIES OR EVEN LIGHT SNOW. THE BEST CHANCE OF "FLAKY
STRATUS" LOOKS TO BE THURSDAY INTO THURSDAY NIGHT AS THAT SECONDARY
SURGE OF COLD AIR ARRIVES...BUT JUST ABOUT ANY WEAK IMPULSE PIVOTING
AROUND THE TROUGH COULD BE ENOUGH TO PRODUCE SOME LIGHT SNOW OR
FLURRIES.

STRONGER CLIPPER IS STILL PROGGED TO ZIP SOUTHEAST INTO THE REGION
FRIDAY NIGHT INTO SATURDAY AND GIVEN THE COLD AIR MASS IN PLACE
COULD EASILY WRING OUT A SWATH OF A COUPLE/FEW INCHES OF SNOW.
GUIDANCE STILL SUGGESTS THAT THE BEST CHANCES OF THIS WOULD BE IN
OUR SOUTHERN CWA AND GIVEN A COUPLE DAYS OF CONSISTENCY IN THE
MODELS HAVE GONE ABOVE GUIDANCE POPS AND NUDGED UP TO LOW END
LIKELYS. OBVIOUSLY AS WE GET CLOSER TO THE EVENT THE TRACK COULD
NEED TO BE NUDGED NORTH OR SOUTH...BUT DOES LOOKS LIKE SOMEWHERE IN
THE NEIGHBORHOOD STANDS A DECENT SHOT OF SOME ACCUMULATING SNOW. A
MODERATING TREND STILL APPEARS TO BE IN THE OFFING LATER IN THE
WEEKEND INTO EARLY NEXT WEEK AS THE UPPER FLOW FLATTENS OUT.

IZZI

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 20Z...

* NW WINDS INCREASING THROUGH THE AFTN AND GUSTING TO 25-30 KT
BY LATE AFTN AND EVENING.

* AREAS OF RAIN/SNOW CHANGING TO ALL SNOW. VSBY BRIEFLY DOWN TO
1-3 MILES AT ORD THROUGH EARLY EVENING.

* CONDITIONS IMPROVING TO MVFR CIG/VSBY THIS EVE.

ALLSOPP

//DISCUSSION...UPDATED 20Z...

AREAS OF SNOW ARE MOVING ACROSS EASTERN IA AND NORTHERN
IL...MAINLY DPA...ORD NORTHWARD. LESS IMPACT AT MDW. VSBY AT TIMES
1-3 MILES BUT THEN BOUNCING UP TO VFR. EXPECT A DUSTING TO 1/2
INCH ACCUMULATION.

PREVIOUS DISCUSSION 18Z...

WEAK LOW PRESSURE OVER CHICAGO AT NOON...WILL MOVE NORTHEAST ACROSS
SOUTHERN LAKE MI THIS AFTERNOON. WINDS SHIFT NW IN THE WAKE OF THE
LOW...AND LIGHT RAIN AND DRIZZLE MIXES WITH AND CHANGES TO SNOW.
HOWEVER RADAR TRENDS SHOW THE BACK EDGE OF PRECIP LIFTING RAPIDLY
NORTHEAST ABOUT THE TIME PRECIP CHANGES FROM RAIN TO SNOW...SO NO
ACCUMULATION EXPECTED AT ORD OR MDW. IN FACT...VISIBILITY WILL
IMPROVE RAPIDLY THIS AFTERNOON AS PRECIP ENDS AND COLDER DRIER AIR
ARRIVES. IFR CIGS HAVE BEEN RUNNING AROUND 600 TO 800 FEET BUT
SHOULD GRADUALLY IMPROVE TO MVFR AROUND 1000-1500 FT DURING THE
AFTERNOON. CIGS SHOULD GRADUALLY LIFT TO AROUND 2000 FT OR BETTER
THIS EVENING.

AS CIGS AND VSBYS IMPROVE...NORTHWEST WINDS WILL BE PICKING UP
THROUGH THE AFTERNOON. STRONG ARCTIC HIGH PRESSURE BUILDING INTO
THE CENTRAL PLAINS WILL CREATE A TIGHT PRESSURE GRADIENT WHICH
WILL PERSIST INTO THURSDAY NIGHT. BY MID TO LATE THIS AFTERNOON
WINDS WILL BE 15-20 KT SUSTAINED WITH GUSTS 25-30 KT. WINDS MAY
DIMINISH SLIGHTLY LATE TONIGHT EARLY THU MORNING...BUT GUSTS WILL
PICK UP TO 25-30 AGAIN LATE MORNING AND AFTERNOON.

ALLSOPP

//ORD AND MDW CONFIDENCE...UPDATED 20Z...

* HIGH CONFIDENCE IN WIND FORECAST.

* LOW TO MEDIUM CONFIDENCE IN CIG/VSBY TRENDS WITH SNOW. LOTS OF
VARIABILITY IN VSBY NEXT SEVERAL HOURS.

* MEDIUM-HIGH CONFIDENCE IN IMPROVING CIG/VSBY THIS EVENING.

ALLSOPP

//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...

THURSDAY NIGHT...VFR.

FRIDAY...VFR...THEN MVFR AND A CHANCE OF SNOW OVERNIGHT.

SATURDAY...MVFR BECOMING VFR.

SUNDAY...VFR.

MONDAY...VFR.

TUESDAY...VFR.

TRS

.MARINE...
208 PM CST

ELONGATED AREA OF LOW PRESSURE STRETCHED FROM SOUTHERN LAKE MICHIGAN
INTO SOUTHERN QUEBEC THIS AFTERNOON...WITH LOW PRESSURE CENTER OVER
SOUTHWEST LOWER MICHIGAN EXPECTED TO DEEPEN AS IT LIFTS NORTHEAST
AWAY FROM LAKE MICHIGAN TONIGHT. THE COMBINATION OF TIGHTENING
SURFACE PRESSURE GRADIENT AND THE ADVECTION OF MUCH COLDER AIR
BEHIND THE LOW WILL PROVIDE FOR NORTH-NORTHWEST GALES ACROSS THE
LAKE TONIGHT. WINDS WILL GRADUALLY EASE BELOW GALE FORCE THURSDAY
MORNING...THOUGH WITH CANADIAN HIGH PRESSURE BUILDING SOUTHEAST
ACROSS THE PLAINS THE GRADIENT WILL REMAIN FAIRLY STOUT. THIS WILL
KEEP WINDS IN THE 20-30 KT RANGE THROUGH THURSDAY NIGHT AND EARLY
FRIDAY...THOUGH WITH A MORE-BACKED WEST-NORTHWEST DIRECTION.

GIVEN THE EXPECTED PROGRESSION OF WIND TRENDS...THE CURRENT GALE
WARNING FOR THE LAKE MICHIGAN OPEN WATERS APPEARS REASONABLE RUNNING
THROUGH 9 AM CST THURSDAY...THOUGH COULD PERHAPS SEE A FEW GALE
FORCE GUSTS LINGER ACROSS THE SOUTHEAST PART OF THE LAKE THROUGH
LATE THURSDAY MORNING. TIMING OF THE GALE WARNING FOR INDIANA
NEARSHORE ZONES ENDING AT 4 AM CST THURSDAY ALSO STILL APPEARS ON
TRACK. SMALL CRAFT ADVISORIES WILL LIKELY NEED TO BE CARRIED THROUGH
MUCH OF FRIDAY...PARTICULARLY FOR THE INDIANA NEARSHORE ZONES WHERE
WAVES WILL BE SLOWEST TO COME DOWN IN PERSISTENT WEST-NORTHWEST
FLOW.

WINDS SHOULD DECREASE MORE MARKEDLY ACROSS THE LAKE BY FRIDAY
AFTERNOON AS THE NORTHERN EXTENSION OF THE SURFACE HIGH PRESSURE
RIDGE AXIS MOVES ACROSS THE AREA. A WEAK CLIPPER-TYPE LOW PRESSURE
SYSTEM IS ANTICIPATED TO MOVE ACROSS THE MIDWEST SOUTH OF THE LAKES
SATURDAY WHICH MAY RESULT IN SOME FLUCTUATION IN WIND DIRECTION
DEPENDING ON DETAILS OF LOW TRACK...THOUGH WINDS SHOULD REMAIN LESS
THAN 20 KTS. A SECOND STRONGER LOW WILL PASS ACROSS THE NORTHERN
LAKES SATURDAY NIGHT...WHICH WILL RESULT IN ANOTHER FAIRLY SHORT
PERIOD OF STRONGER 30 KT NORTHWEST WINDS LATER SATURDAY NIGHT INTO
SUNDAY. WINDS WILL COME BACK DOWN AS HIGH PRESSURE RIDGING THEN
MOVES IN QUICKLY AGAIN SUNDAY NIGHT.

RATZER

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ008 UNTIL 4 PM
WEDNESDAY.

IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM THURSDAY.

SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 AM FRIDAY.

GALE WARNING...INDIANA NEARSHORE WATERS UNTIL 4 AM THURSDAY.

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

157 PM CST WED JAN 30 2013

.DISCUSSION...
944 AM CST

JEE

//PREV DISCUSSION...
353 AM CST

FORECAST CHALLENGES THIS MORNING INCLUDE POTENTIAL FOR SNOW
TODAY...CLOUD COVER AND ITS POTENTIAL IMPACTS ON TEMPS...AND CLIPPER
SYSTEM ARRIVING FRIDAY NIGHT INTO SATURDAY.

IZZI

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 20Z...

* NW WINDS INCREASING THROUGH THE AFTN AND GUSTING TO 25-30 KT
BY LATE AFTN AND EVENING.

* AREAS OF RAIN/SNOW CHANGING TO ALL SNOW. VSBY BRIEFLY DOWN TO
1-3 MILES AT ORD THROUGH EARLY EVENING.

* CONDITIONS IMPROVING TO MVFR CIG/VSBY THIS EVE.

ALLSOPP

//DISCUSSION...UPDATED 20Z...

PREVIOUS DISCUSSION 18Z...

ALLSOPP

//ORD AND MDW CONFIDENCE...UPDATED 20Z...

* HIGH CONFIDENCE IN WIND FORECAST.

* LOW TO MEDIUM CONFIDENCE IN CIG/VSBY TRENDS WITH SNOW. LOTS OF
VARIABILITY IN VSBY NEXT SEVERAL HOURS.

* MEDIUM-HIGH CONFIDENCE IN IMPROVING CIG/VSBY THIS EVENING.

ALLSOPP

//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...

THURSDAY NIGHT...VFR.

FRIDAY...VFR...THEN MVFR AND A CHANCE OF SNOW OVERNIGHT.

SATURDAY...MVFR BECOMING VFR.

SUNDAY...VFR.

MONDAY...VFR.

TUESDAY...VFR.

TRS

.MARINE...
345 AM CST

RODRIGUEZ

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ008 UNTIL 4 PM
WEDNESDAY.

IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM THURSDAY.

SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 AM FRIDAY.

GALE WARNING...INDIANA NEARSHORE WATERS UNTIL 4 AM THURSDAY.

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

1155 AM CST WED JAN 30 2013

.DISCUSSION...
944 AM CST

JEE

//PREV DISCUSSION...
353 AM CST

FORECAST CHALLENGES THIS MORNING INCLUDE POTENTIAL FOR SNOW
TODAY...CLOUD COVER AND ITS POTENTIAL IMPACTS ON TEMPS...AND CLIPPER
SYSTEM ARRIVING FRIDAY NIGHT INTO SATURDAY.

IZZI

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 18Z...

* WIND SHIFTING NW AT ORD AROUND 18Z AND MDW AROUND 19Z.

* IFR VSBY INCREASING RAPIDLY TO VFR AS MAIN AREA OF PRECIP ENDS
EARLY AFTN.

* LIGHT RAIN MAY MIX WITH SNOW BRIEFLY EARLY AFTN BEFORE PRECIP
ENDS.

* IFR CIG GRADUALLY IMPROVING TO MVFR BY EVENING.

* NW WINDS INCREASING THROUGH THE AFTN AND GUSTING TO NEAR 30 KT
LATE AFTN AND OVERNIGHT.

ALLSOPP

//DISCUSSION...UPDATED 18Z...

ALLSOPP

//ORD AND MDW CONFIDENCE...UPDATED 18Z...

* HIGH CONFIDENCE IN WIND FORECAST.

* MEDIUM CONFIDENCE IN VISIBILITY AND PRECIP TRENDS.

* MEDIUM-HIGH CONFIDENCE IN CIG TREND.

ALLSOPP

//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...

THURSDAY NIGHT...VFR.

FRIDAY...VFR...THEN MVFR AND A CHANCE OF SNOW OVERNIGHT.

SATURDAY...MVFR BECOMING VFR.

SUNDAY...VFR.

MONDAY...VFR.

TUESDAY...VFR.

TRS

.MARINE...
345 AM CST

RODRIGUEZ

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ008 UNTIL 4 PM
WEDNESDAY.

IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM THURSDAY.

SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 AM FRIDAY.

GALE WARNING...LMZ743-LMZ744-LMZ745...4 PM WEDNESDAY TO 4 AM
THURSDAY.

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

1009 AM CST WED JAN 30 2013

.DISCUSSION...
944 AM CST

JEE

//PREV DISCUSSION...
353 AM CST

FORECAST CHALLENGES THIS MORNING INCLUDE POTENTIAL FOR SNOW
TODAY...CLOUD COVER AND ITS POTENTIAL IMPACTS ON TEMPS...AND CLIPPER
SYSTEM ARRIVING FRIDAY NIGHT INTO SATURDAY.

IZZI

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 16Z...

* ENE WINDS LESS THAN 10 KT SHIFTING TO NW AROUND 18Z AT ORD AND
19Z MDW.

* NW WINDS INCREASING THROUGH THE AFTN WITH GUSTS NEAR 30 KT LATE
AFTN AND EVENING.

* IFR CIG/VSBY IN RAIN DRIZZLE...CHANGING TO SNOW MID AFTN AND
ENDING LATE AFTN. LITTLE OR NO ACCUMULATION.

* CIG/VSBY IMPROVING TO MVFR BY EVENING.

ALLSOPP

//DISCUSSION...UPDATED 14Z...

WEAK LOW PRESSURE OVER CENTRAL IL WILL MOVE OVER CHICAGO AROUND
18Z. THIS WILL GIVE ORD AND DPA NE WINDS THIS MORNING. MDW AND GYY
MAY GO LIGHT AND VARIABLE AND GYY MAY EVEN GO LIGHT SOUTHWEST FOR
A COUPLE HOURS. AS LOW PASSES...WINDS WILL BACK AROUND TO
NORTHWEST. WINDS SPEEDS WILL RAMP UP LATE AFTERNOON AND EVENING.

ALLSOPP

PREVIOUS DISCUSSION 12Z...

THE LARGE NE-SW BAND OF RAIN CONTINUED TO SHIFT FURTHER AWAY TO
THE EAST OVERNIGHT AND EARLY THIS MORNING. MEANWHILE...LIGHT RAIN
WAS QUICKLY ENDING ACROSS NORTHERN IL AND NORTHEAST IN AS A DRY
SLOT...QUITE EVIDENT IN BOTH WATER VAPOR SATELLITE AND COMPOSITE
RADAR LOOPS...CONTINUES TO PUNCH ACROSS NORTHERN IL INTO FAR
SOUTHERN WI EARLY THIS MORNING. PRECIPITATION SHOULD BE LIMITED
TO DRIZZLE AND SPOTTY SHOWERS UNTIL MIDDAY WITH THE DRYING ALOFT
BUT SMALL DEW POINT DEPRESSIONS PERSISTING IN THE LOW LEVELS.

THE MID LEVELS ARE SHOWN TO MOISTEN UP AGAIN BY LATE MORNING AS
THE POSITIVELY TILTED MID AND UPPER LEVEL TROUGHS SHIFT EASTWARD
AND ACROSS THE LOCAL AREA DURING THE LATE MORNING THROUGH EARLY
EVENING. THIS WILL RESULT IN A RETURN OF MORE SIGNIFICANT
PRECIPITATION TO THE AREA.

WITH COLD AIR AS FAR SOUTH AS NM AND NORTHERN TX COLD AIR
ADVECTION WILL BE OCCURRING IN THE MID AND LOWER LEVELS DESPITE
THE SOUTHWEST FLOW AHEAD OF THE TROUGHS. A NORTHEAST TO SOUTHWEST
ORIENTED COLD FRONT MOVED ACROSS THE LOCAL AREA DURING THE NIGHT
SHIFTING WINDS TO OUT OF THE NORTH AND NORTHEAST. THIS BROUGHT
COLDER BOUNDARY LAYER AIR TO THE AREA. LOW LEVEL COLD AIR
ADVECTION WILL INCREASE DURING THE LATE MORNING AND AFTERNOON AS
LOW PRESSURE MOVES NORTHEAST FROM NORTHEAST MO/WEST CENTRAL IL TO
FAR NORTHEAST IL BY 18Z.

BY MIDDAY MODEL TEMPERATURE PROFILES SHOW ALL BUT THE NEAR GROUND
LEVEL TO BE ALL BELOW 0C. AS THE PRECIPITATION RETURNS IT WILL
LIKELY BE A MIX OF RAIN AND SNOW BEFORE TURNING TO ALL LIGHT SNOW
BY EARLY AFTERNOON. THIS LIGHT SNOW WILL END IN THE EARLY EVENING
AS THE UPPER TROUGH AXIS MOVES EAST OF THE AREA.

WITH NARROW TEMPERATURE AND DEW POINT SPREADS ON BOTH SIDES OF THE
FRONT SLICING ACROSS FAR SOUTHWEST LOWER MI TO NORTHEAST MO IFR
STRATUS CEILINGS ARE EXPECTED TO PERSIST INTO TONIGHT. DURING
TONIGHT THE LOWEST LEVELS DRY SOMEWHAT SO CLOUD BASES SHOULD RISE
TO MVFR.

AS THE SURFACE LOW CONTINUES ON NORTHEASTWARD FROM NORTHEAST IL
ACROSS THE GREAT LAKES LATER TODAY WHILE A RIDGE OF HIGH PRESSURE
BUILDS SOUTH-SOUTHEAST ACROSS THE NORTHERN PLAINS THE PRESSURE
GRADIENT ACROSS THE AREA TIGHTENS CONSIDERABLY BY LATE
MORNING/EARLY AFTERNOON. SUSTAINED WINDS OF 15 TO 20KT WITH GUSTS
TO AROUND 30KT ARE LIKELY BY EARLY AFTERNOON. WINDS WILL BE
GRADUALLY BACKING TO NORTHWEST AND WEST-NORTHWEST AS THE LOW
MOVES FURTHER AWAY AND THE COLD FRONT SINKS INTO CENTRAL IN AND
SOUTHERN IL.

TRS

//ORD AND MDW CONFIDENCE...UPDATED 16Z...

* HIGH CONFIDENCE IN WIND FORECAST

* MEDIUM CONFIDENCE IN CIG/VSBY FORECAST

* LOW CONFIDENCE IN ANY ACCUMULATING SNOW

ALLSOPP

//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...

THURSDAY NIGHT...VFR.

FRIDAY...VFR...THEN MVFR AND A CHANCE OF SNOW OVERNIGHT.

SATURDAY...MVFR BECOMING VFR.

SUNDAY...VFR.

MONDAY...VFR.

TUESDAY...VFR.

TRS

.MARINE...
345 AM CST

RODRIGUEZ

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ008 UNTIL 4 PM
WEDNESDAY.

IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM THURSDAY.

SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 AM FRIDAY.

GALE WARNING...LMZ743-LMZ744-LMZ745...4 PM WEDNESDAY TO 4 AM
THURSDAY.

AREA FORECAST DISCUSSION...UPDATED

NWS CHICAGO/ROMEOVILLE IL

944 AM CST WED JAN 30 2013

.DISCUSSION...
944 AM CST

JEE

.PREV DISCUSSION...
353 AM CST

FORECAST CHALLENGES THIS MORNING INCLUDE POTENTIAL FOR SNOW
TODAY...CLOUD COVER AND ITS POTENTIAL IMPACTS ON TEMPS...AND CLIPPER
SYSTEM ARRIVING FRIDAY NIGHT INTO SATURDAY.

IZZI

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 14Z...

* NORTHEAST WINDS LESS THAN 10 KT NOT TURNING NORTHWEST TIL AROUND
17-19Z

* IFR CIG/VSBY IN LIGHT RAIN DRIZZLE...MIXING WITH/CHANGING TO
SNOW AFTERNOON

* NORTHWEST WINDS INCREASING AND GUSTING TO NEAR 30 KT LATE AFTN
AND EVENING

ALLSOPP

//DISCUSSION...UPDATED 14Z

ALLSOPP

PREVIOUS DISCUSSION 12Z...

TRS

//ORD AND MDW CONFIDENCE...UPDATED 14Z...

* WINDS...MEDIUM-HIGH

* CIG/VSBY...MEDIUM-HIGH

* SNOW...LOW-MEDIUM

ALLSOPP

//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...

THURSDAY NIGHT...VFR.

FRIDAY...VFR...THEN MVFR AND A CHANCE OF SNOW OVERNIGHT.

SATURDAY...MVFR BECOMING VFR.

SUNDAY...VFR.

MONDAY...VFR.

TUESDAY...VFR.

TRS

.MARINE...
345 AM CST

RODRIGUEZ

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ008 UNTIL 4 PM
WEDNESDAY.

IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM THURSDAY.

SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 AM FRIDAY.

GALE WARNING...LMZ743-LMZ744-LMZ745...4 PM WEDNESDAY TO 4 AM
THURSDAY.

AREA FORECAST DISCUSSION

NWS NORTHERN INDIANA

1235 PM EST WED JAN 30 2013

.AVIATION...

18Z TAFS...STRONG COLD FRONT CURRENTLY NEAR IN/IL STATE LINE PER
RECENT OBS WILL PUSH EAST ACROSS THE AREA LATE THIS AFTERNOON INTO
EVENING. IFR CONDS AT KSBN THIS AFTN WILL LIFT TO MVFR WITH
FROPA...CURRENTLY TIMED BETWEEN 23Z AND 01Z. SCATTERED RAIN AHEAD
OF THE FRONT WILL CHANGE OVER TO ALL SNOW AFTER 01Z AT KSBN...WITH
MVFR CIGS/VISBYS EXPECTED THROUGH THE OVERNIGHT. RECENT OBS AND
SAT TRENDS THIS AM/AFTN SHOW IFR CIGS JUST WEST OF KFWA...WITH
LOWERING CONFIDENCE OF IFR REACHING TERMINAL. REFLECTED WITH
TEMPO IFR CIGS THROUGH 20Z...AND SHOULD REMAIN MVFR AFTERWARD WITH
STRONGER GRADIENT AHEAD OF FRONT...SUPPORTED BY OB TRENDS. PRECIP
SHOULD BE MOSTLY ENDED AT KFWA WITH FROPA...HOWEVER SOME -SN MAY
BE PRESENT 03Z AND AFTER...BUT CONFIDENCE TOO LOW TO INCLUDE
MENTION IN THIS TAF ISSUANCE. WINDS GUSTING NEAR 30KTS EXPECTED
ALONG/BEHIND FROPA.

.PREV DISCUSSION... /ISSUED 1033 AM EST WED JAN 30 2013/

UPDATE...
QUICK UPDATE SENT TO ADD IN MENTION OF DRIZZLE IN NW AREAS AS
INCREASING LL LIFT AND NEARLY SATURATED BOUNDARY LAYER AREA
RESULTING IN AREAS OF DRIZZLE EXPANDING ACROSS THE NW QUARTER TO
HALF OF THE AREA. THINK THIS WILL BE SHORT LIVED AS COLD FRONT
APPROACHES FROM THE SW WITH DEEPER FORCING AND MSTR. BROKEN LINE
OF SHOWERS ACCOMPANIES THE FRONT WITH HRRR RUNS OVER THE PAST
COUPLE OF HOURS SHOWING AN EXPANDING AREA OF SHOWERS WITH GUSTY
WINDS (30 TO 35 KTS). FOR THE TIME BEING LIKELY POPS INHERITED
FROM OVERNIGHT FORECAST WILL WORK. MAY NEED AN ADDITIONAL UPDATE
IN A FEW HOURS IF COVERAGE DOES EXPAND AS HINTED AT. CHANGE OVER
TIMING ALSO LOOKS REASONABLE AT THIS STATE WITH FAR W/NW AREAS
SEEING A MIX OR FULL SWITCH IN THE 22Z TO 01Z TIME FRAME AND THEN
MARCHING EAST TO THE IN/OH STATE LINE IN THE 00-03Z WINDOW.

PREV DISCUSSION... /ISSUED 409 AM EST WED JAN 30 2013/

SHORT TERM...
PREFNTL CONV LINE CONTS TO ACCELERATE EWD EARLY THIS MORNING IN
RESPONSE TO UPSTREAM SW TROUGH EJECTING NEWD OUT OF KS. PRIMARY CDFNT
STILL LAGS APPRECIABLY WWD AN ANCHORED TO SFC CYCLONE OVR NRN IL.

00Z GUIDANCE TAKEN AS A WHOLE MOSTLY AGREEABLE SHRT TERM W/CONTD
NEWD EJECTING OF MAIN UPR TROUGH AND EWD DRIVING WEDGE OF ARCTIC AIR
TONIGHT. WILL DELAY CDFNT PROGRESSION SLIGHTLY FM PRIOR FCST PER
UPSTREAM TRENDS AND NR TERM RUC/HRRR GUIDANCE. THIS ALSO
NECESSITATES A UPWARD BUMP/EXPANSION IN POPS NW HALF THIS AFTN FOR
COMBINATION OF REDVLPG SHRA ALG SFC BNDRY AND MID LVL DEFORMATION
ZONE CLIPPING NWRN AREAS LT. OTRWS RAPID DEEPENING OF LL CAA WING
WILL CHG THINGS OVR RAPIDLY W-E THIS EVENING HWVR PALTRY SNOW AMTS
XPCD...INCH OR LESS.

LL THERMAL TROUGH BLDS ACRS THE LAKES LTR TONIGHT AND MAXIMIZES INTO
FRI. WHILE INITIAL SHRT FETCH WRLY FLW TRAJECTORY LIMITING
OVERNIGHT...SECONDARY SW TROUGH DROPPING RAPIDLY SEWD OUT OF AB AND
ATTENDANT MID LVL MSTR PLUME SHLD SEED A PD OF ENHANCED LK EFFECT LT
THU AFTN THOUGH FRI AM ESP IN CONTEXT OF ADDNL LL VEERING AND MUCH
IMPROVED FETCH. PRIOR DELINEATION OF HIGHEST BOUND POPS DEEMED CLOSE
BUT DID ERODE SRN EXTENT PER LATEST CONSENSUS.

LONG TERM...FRIDAY THROUGH TUESDAY

LAKE EFFECT WILL BE TAPERING OFF DURING THE DAY FRIDAY. STOUT
SUBSIDENCE INVERSION WILL DEVELOP BY FRIDAY AFTERNOON IN THE WAKE OF
DEPARTING SHORTWAVE. MEANWHILE...LOW LEVEL WINDS WILL BACK TO THE
SOUTHWEST AS RIDGE AXIS QUICKLY SHIFTS EAST OF HERE. THESE TWO
PROCESSES WILL CAUSE LAKE EFFECT BANDS TO SHIFT NORTH AND WEAKEN AS
THE DAY PROGRESSES. THIS WILL TAKE SOME TIME THOUGH AND WITH
CONVECTIVE DEPTHS STILL AROUND 7 KFT AND WIND DIRECTION STILL AROUND
290 BY LATE FRIDAY MORNING...ADDITIONAL ACCUMULATIONS OF AROUND AN
INCH ARE POSSIBLE MAINLY IN BERRIEN AND CASS COUNTIES BETWEEN 12Z
AND 18Z. MAIN STORY FOR THE REST OF THE CWA WILL BE VERY COLD TEMPS.
THERMAL TROUGH WILL BE MOVING OVERHEAD FRIDAY MORNING WITH 925MB
TEMPS AROUND -18C. THERMAL PROFILES WILL START TO REBOUND BY LATE
FRIDAY WITH DEVELOPING SOUTHWEST FLOW BUT THIS WILL LIKELY BE TOO
LITTLE TOO LATE TO GET HIGHS OUT OF THE MID TO UPPER TEENS. DECENT
GRADIENT WILL ALSO SUPPORT WINDS OF 10-20 MPH...MAKING IT FEEL LIKE
THE SINGLE DIGITS BELOW ZERO. WAA WILL KEEP OVERNIGHT LOWS
RELATIVELY WARM THOUGH...GENERALLY HOLDING STEADY IN THE LOW TO MID
TEENS.

LATEST MODEL SUITE HAS COME INTO BETTER AGREEMENT REGARDING THE
TIMING AND EVOLUTION OF NEXT SHORTWAVE MOVING ACROSS THE REGION
EARLY SATURDAY MORNING. PV ANOMALY ITSELF IS RATHER NONDESCRIPT AND
THERE IS NO UPPER LEVEL JET SUPPORT WITH MAINLY CONFLUENT FLOW ALOFT
OVER THE EASTERN HALF OF THE COUNTRY. THERE WILL BE A DECENT BAND OF
SYSTEM RELATIVE ISENTROPIC ASCENT AHEAD OF THE WAVE THOUGH. MOISTURE
WILL BE LIMITED BUT WE COULD SQUEEZE OUT SOME LIGHT SNOW
ACCUMULATIONS OF 1-2 INCHES BY MIDDAY SATURDAY. A SECOND AND
SLIGHTLY MORE IMPRESSIVE VORT MAX WILL THEN MOVE ACROSS THE GREAT
LAKES SATURDAY NIGHT. DYNAMICS ARE MUCH BETTER BUT BEST QG OMEGA
LOOKS TO PASS MAINLY NORTH OF HERE. COULD BE SOME LAKE ENHANCEMENT
BUT INVERSION HEIGHTS LOOK RELATIVELY LOW AND 850MB TEMPS ARE NOT
NEARLY AS COLD AS THURSDAYS EVENT. WILL CONTINUE WITH LOW CHANCE
POPS MAINLY ACROSS THE NORTH. LOOKS LIKE WE WILL GET ONE QUIET
WEATHER DAY ON SUNDAY BEFORE YET ANOTHER CLIPPER SYSTEM MOVES ACROSS
THE REGION ON MONDAY. 00Z GFS AND ECMWF KEEP MOST OF THE PRECIP
NORTH OF HERE BUT TRACK ERRORS THIS FAR OUT ARE ALMOST CERTAIN WITH
FAST NORTHWEST FLOW AND A PARADE OF LOW AMPLITUDE WAVES. WILL
MAINTAIN LOW CHANCE POPS YET AGAIN. PTYPES MAY ACTUALLY BE RAIN WITH
THIS EVENT THOUGH. TEMPS WILL GRADUALLY MODERATE THROUGH EARLY NEXT
WEEK WITH WAA LIKELY PUSHING HIGHS TO 40F BY MONDAY. OVERNIGHT LOWS
WILL UNDERGO A SIMILAR MODERATING TREND WITH VALUES GENERALLY IN THE
UPPER TEENS TO MID 20S...SLIGHTLY ABOVE NORMAL FOR EARLY
FEBRUARY.

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...GALE WARNING FROM 5 PM THIS AFTERNOON TO 5 AM EST THURSDAY FOR
LMZ043-046.

SHORT TERM...T
LONG TERM...AGD
UPDATE...FISHER
AVIATION...NG

AREA FORECAST DISCUSSION

NWS NORTHERN INDIANA

1033 AM EST WED JAN 30 2013

.UPDATE...
QUICK UPDATE SENT TO ADD IN MENTION OF DRIZZLE IN NW AREAS AS
INCREASING LL LIFT AND NEARLY SATURATED BOUNDARY LAYER AREA
RESULTING IN AREAS OF DRIZZLE EXPANDING ACROSS THE NW QUARTER TO
HALF OF THE AREA. THINK THIS WILL BE SHORT LIVED AS COLD FRONT
APPROACHES FROM THE SW WITH DEEPER FORCING AND MSTR. BROKEN LINE
OF SHOWERS ACCOMPANIES THE FRONT WITH HRRR RUNS OVER THE PAST
COUPLE OF HOURS SHOWING AN EXPANDING AREA OF SHOWERS WITH GUSTY
WINDS (30 TO 35 KTS). FOR THE TIME BEING LIKELY POPS INHERITED
FROM OVERNIGHT FORECAST WILL WORK. MAY NEED AN ADDITIONAL UPDATE
IN A FEW HOURS IF COVERAGE DOES EXPAND AS HINTED AT. CHANGE OVER
TIMING ALSO LOOKS REASONABLE AT THIS STATE WITH FAR W/NW AREAS
SEEING A MIX OR FULL SWITCH IN THE 22Z TO 01Z TIME FRAME AND THEN
MARCHING EAST TO THE IN/OH STATE LINE IN THE 00-03Z WINDOW.

.PREV DISCUSSION... /ISSUED 409 AM EST WED JAN 30 2013/

LONG TERM...FRIDAY THROUGH TUESDAY

AVIATION...

WIDESPREAD LT-MOD STRATIFORM RAIN DEFINED BY VFR CIGS AND POCKETS
OF MVFR VSBYS CONTS WITHIN BROAD SWRLY FLW AND CONTD LL THETA-E
ADVTN/MSTR TRANSPORT AHD OF UPSTREAM SW TROUGH OVR NW MO AND
DOUBLE BARREL SFC LOW XTNDG FM SE MI INTO SRN MO. HWVR HEAVIER
RAIN WILL CONT TO SHUNT QUICKLY NEWD THROUGH DAWN IN RESPONSE TO
WKNG LLJ. LEADING EDGE OF UPSTREAM CAA WING WORKING INTO CNTRL IL
ATTM AND A BIT SLWR EVEN THAN 00Z GUIDANCE HAD INDICATED AND WILL
BACK ARRIVAL OF IFR/LIFR CONDS INTO THE TERMINALS A BIT LATER W/12Z
ISSUANCE. OTRWS STG CAA WING WILL ARRIVE TWD 00Z W/STG WRLY WINDS
DVLPG W/SFC GUSTS AOA 30KTS THROUGH LT EVENING XPCD. WILL ADDRESS
THIS AND PD OF ACCUMULATING SNOW AT KSBN THIS EVENING W/12Z
ISSUANCE.

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...GALE WARNING FROM 5 PM THIS AFTERNOON TO 5 AM EST THURSDAY FOR
LMZ043-046.

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

AREA FORECAST DISCUSSION

NWS BILLINGS MT

1024 AM MST WED JAN 30 2013

.SHORT TERM...VALID FOR TDY AND THU...

SEVERAL UPDATES TO THE FORECAST THIS MORNING WITH THIS VERY ACTIVE
AND DIFFICULT WEATHER PATTERN.

FIRST UPDATE THIS MORNING HAS BEEN TO INCREASE WINDS FOR SHERIDAN
COUNTY WYOMING TO ASHLAND AND BROADUS FOR THIS AFTERNOON AND
EVENING. THE NAM AND RAP ARE CATCHING ON TO A STRONGER SURFACE LOW
OVER WYOMING THIS MORNING THAN MODELS HAD PREVIOUSLY ADVERTISED.
AS THIS SURFACE LOW SHIFTS SOUTH AND EAST THIS MORNING AHEAD OF
THE NEXT COLD FRONT...EXPECT WINDS WILL INCREASE OUT OF THE
NORTHWEST ACROSS THE AREAS...WITH GUSTS 30 TO 40 MPH
COMMON...ESPECIALLY IN HIGHER TERRAIN LOCATIONS INCLUDING ABERDEEN
HILL ALONG I90. GIVEN THE RECENT SNOW COVER IN THESE LOCATIONS AND
SNOW EXPECTED THROUGH THIS EVENING IN THESE LOCATIONS...BLOWING
SNOW WILL BECOME A TRAVEL HAZARD ALONG SECTIONS OF I90 AND US 212.
HAVE ALSO ADDED THIS BLOWING SNOW WORDING TO THE WINTER WEATHER
ADVISORY ALREADY IN PLACE FOR THESE LOCATIONS. THE STRONGEST WINDS
WILL SHIFT EAST THIS EVENING AS THE COLD FRONT ROLLS THROUGH THOSE
LOCATIONS...WITH THE BLOWING DIMINISHING BY THURSDAY MORNING.

MOIST WESTERLY FLOW INTO THE PARADISE VALLEY THIS MORNING WILL
CONTINUE THROUGH TONIGHT AND INTO THURSDAY MORNING. MODELS ARE
BECOMING MORE CONFIDENT IN A PROLONGED UPSLOPE SNOW EVENT INTO THE
ABSAROKA MOUNTAINS ON THE EAST SIDE OF THE VALLEY. THUS HAVE
ISSUED A WINTER WEATHER ADVISORY FOR 3 TO 6 INCHES OF SNOW AND
BLOWING SNOW. THE HIGHEST SNOW AMOUNTS WILL BE LOCATED ALONG AND
EAST OF HIGHWAY 89.

LASTLY...EXPANDED POPS THIS MORNING TO ACCOUNT FOR MORE WIDESPREAD
SNOWFALL THAT PREVIOUSLY ANTICIPATED. LATEST MODEL RUNS CONTINUE
TO INDICATE THE BEST TIME FOR SNOWFALL TO BACK INTO THE BILLINGS
AREA WILL BE THIS EVENING AND OVERNIGHT. HOWEVER...WILL HAVE TO
CONTINUE TO WATCH HOW QUICKLY THIS SNOW BACKS IN TO THE WEST...AS
THE LATEST GFS IS MORE AGGRESSIVE AND WOULD RESULT IN HIGHER
SNOWFALL AMOUNTS...WITH SNOW BEGINNING THIS AFTERNOON.

CHURCH
&&

.LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE...

FRIDAY WILL SEE THE DEPARTURE OF THE ARCTIC INTO THE DAKOTAS BUT
NOT BEFORE A SHORTWAVE IN NORTHWEST FLOW ALOFT FORCES SOME SHOWER
ACTIVITY. DEFINITELY WILL SEE WARMING TEMPERATURES ACROSS THE EAST
AND WITH MOST OF THE PRECIP FALLING INTO DOWNSLOPING WINDS DO NOT
EXPECT MUCH IN THE WAY OF AMOUNTS. SHOULD SEE 15 TO 20 DEGREE
TEMPERATURE INCREASES ACROSS THE CENTRAL AND EASTERN ZONES WITH
THE WEST BEING WINDY AND MIXED WITH TEMPERATURES IN THE 40S.

UPPER LEVEL RIDGE WEST OVER THE PACIFIC NORTHWEST ON SATURDAY
BEGINS TO SHIFT EAST AND FLATTEN THROUGH SUNDAY. THIS SUPPORTS
CONTINUALLY FALLING SURFACE PRESSURES EAST OF THE CONTINENTAL
DIVIDE AND TIGHTENS WIND GRADIENTS FOR GAP FLOW AREAS. THIS WILL
BRING DRY AND WARMER CONDITIONS BUT AM STAYING A BIT BELOW
GUIDANCE AS DRAINAGE FLOWS AND EXISTING SNOW COVER COULD LIMIT
FULL WARMING.

MONDAY A TROUGH BEGINS BUILDING ALONG THE WEST COAST AND HEIGHTS
BUILD AGAIN ACROSS THE REGION. STRONG FLOW ALOFT OVER THE CANADIAN
ROCKIES KEEPS LEESIDE TROUGHING IN PLACE SO EXPECT WIND TO BE
UNYIELDING FOR LIVINGSTON AND NYE FOR MOST OF THE EXTENDED. THIS
PATTERN PERSISTS WITH FLUCUATIONS IN THE SURFACE TROUGH STRENGTH
THROUGH TUESDAY. MODELS TRY TO DEVELOP A CUTOFF LOW ALONG THE WEST
COAST LATER IN THE EXTENDED BUT INITIALLY THIS JUST KEEPS THE
RIDGE IN PLACE WITH DRY AND MILD WEATHER WEDNESDAY. BORSUM
&&

.AVIATION...

ARCTIC BOUNDARY BISECTING CENTRAL PORTION OF THE FORECAST AREA
WILL BE THE FOCUS FOR SNOW AND IFR CONDITIONS TODAY AND TONIGHT.
AREAS FROM ROUNDUP TO BILLINGS TO SHERIDAN WILL BE IN THE VICINITY
OF THE BOUNDARY AND WILL SEE PERIODS OF SNOW THROUGH THE NEXT 24
HOURS.

IN THE KSHR VICINITY EXPECT GUSTY NORTHWEST WINDS TO
DEVELOP MID DAY THROUGH EARLY THIS EVENING...WITH GUSTS TO AROUND
35 KTS AT TIMES. THIS WILL PRODUCE SIGNIFICANT BLOWING AND
DRIFTING SNOW ACROSS SOUTHERN BIG HORN AND MUCH OF SHERIDAN COUNTY
RESULTING IN LOCAL LIFR CONDITIONS THROUGH 03Z.

AREAS EAST OF MILES CITY TO BROADUS WILL SEE MAINLY SCATTERED
SNOW SHOWERS TODAY AND TONIGHT WITH OCCASIONAL MVFR CONDITIONS. TO
THE WEST AROUND KLVM GUSTY WEST TO NORTHWEST WINDS WILL KEEP VFR
CONDITIONS IN PLACE...BUT EXPECT GUSTS TO AROUND 35 KTS AT TIMES.
CHAMBERS
&&

.PRELIMINARY POINT TEMP/POPS...

TDY THU FRI SAT SUN MON TUE
-------------------------------------------------------
BIL 030 006/027 022/042 023/042 028/046 028/046 026/048
7/S 75/S 22/J 00/B 01/N 11/N 11/B
LVM 035 020/039 030/041 025/042 030/043 029/046 030/048
7/S 64/S 22/W 11/N 11/N 11/N 11/N
HDN 024 005/022 018/041 017/040 020/043 025/043 023/045
8/S 87/S 22/J 00/U 01/U 11/U 11/U
MLS 011 911/009 008/035 016/037 019/040 023/039 023/041
8/S 64/S 22/J 10/B 01/U 01/B 11/U
4BQ 015 905/013 009/037 016/039 020/041 024/041 021/043
8/S 97/S 22/J 00/U 00/U 01/B 00/U
BHK 007 918/002 902/033 017/034 019/037 020/037 021/039
6/S 41/B 12/J 10/B 00/U 01/B 11/B
SHR 025 005/026 017/039 016/041 017/043 023/044 025/046
9/S 97/S 22/W 00/U 00/U 01/U 01/U

.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...WIND CHILL ADVISORY IN EFFECT FROM 6 PM THIS EVENING TO NOON
MST THURSDAY FOR ZONES 32-33-37.
WINTER WEATHER ADVISORY IN EFFECT UNTIL NOON MST THURSDAY FOR
ZONES 36-38-57-58-64.
WINTER WEATHER ADVISORY IN EFFECT UNTIL 6 AM MST THURSDAY FOR
ZONE 63.
WY...WINTER WEATHER ADVISORY IN EFFECT UNTIL NOON MST THURSDAY FOR
ZONES 98-99.

$$
WEATHER.GOV/BILLINGS

AREA FORECAST DISCUSSION

NWS BINGHAMTON NY

115 PM EST WED JAN 30 2013

510 AM UPDATE...BUMPED UP START TIME OF THE FLOOD WATCH TO 21Z.
PREV BLO..

LOTS TO LOOK AT THIS FCST PCKG. MAIN FOCUS IS ON THE APRCHNG
CDFNT AND DIGGING UPR TROF...WHICH WILL BRING A ROUND OF +RA AND
WIND TO THE RGN STARTING THIS AFTERNOON INTO THE OVRNGT HRS.

POTNL FOR SOME VERY GUSTY WINDS WITH ANY CONVECTION THAT DVLPS
NEAR/ALONG THE FNT. GIVEN THIS AND THE STRONG WINDS XPCTD BEHIND
THE CDFNT ON THU...WE ISSUED A HIGH WIND WATCH FOR THE ENTIRE
RGN.

RECORD TEMPS FOR TDA INCLUDE 54F AT SYR (2006/1914), 52 AT BGM
(1974), AND 66 AT AVP (1947). SYR AND BGM RECORDS ARE GONERS.

.SHORT TERM /THURSDAY THROUGH SATURDAY/...
XPCT STRONG WINDS ON THU. NAM/GFS MOS GDNC SHOWING SUSTAINED 25
TO 30 WHICH IS ONE OF THE BETTER INDICATORS SUGGESTING WARNING
CRITERIA WINDS ALONG THE LAKE PLAIN. ISALLOBARIC FIELDS ALSO MORE
IMPRSV THAN PREV WARNING/ADVISORY EVENT. POTNL FOR WARNING CRITERIA
SPCLY ACRS THE LAKE PLAIN AND PSBLY ADJACENT COUNTIES...WITH AN
ADVISORY APPEARING LIKELY FOR THE REMAINDER OF THE CWA.

.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
FOLLOWED HPC GUIDANCE. MODELS ARE SIMILAR WITH NO LARGE STORMS.
REMAIN UNDER A NORTHEAST US UPPER LEVEL TROF. SEASONABLE WEATHER
WITH WEAK LOW PRESSURE SYSTEMS FOLLOWED BY LAKE EFFECT. ALL PRECIP
WILL BE SNOW WITH HIGHS AROUND 30 AND LOWS IN THE TEENS. THE WEAK
SYSTEMS GO THROUGH SUNDAY AND MONDAY NIGHT...WITH LAKE EFFECT ON
THE OTHER DAYS. COULD BE A 12 HOUR DRY BREAK BETWEEN SYSTEMS WITH
WEAK HIGH PRESSURE MON AFTN.

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
1230 PM UPDATE...
IFR CIGS AT AVP AND MVFR CIGS AT ELM BGM ITH WILL EXPAND AND MOVE
NORTH INTO SYR AND RME THIS AFTN. IN ADDITION RAIN WILL MOVE IN
AND COVER THE ENTIRE AREA BY 20Z. THIS AREA OF RAIN WILL CONTINUE
THROUGH MOST OF TONIGHT. AFTER THE RAIN STARTS VSBYS WILL ALSO
FALL TO MAINLY MVFR. A STRONG COLD FRONT WILL MOVE THROUGH BETWEEN
4 AND 6Z. RAIN WILL END AROUND 11Z BUT AT RME LAKE EFFECT SNOW
WILL START. MOST OF THIS WILL STAY NORTH OF THEM THOUGH WITH A
WEST FLOW BUT CIGS SHOULD STAY MVFR. WITH THE END OF THE RAIN
DRIER AIR WILL COME IN SCATTERING OUT THE MVFR AND IFR CIGS AND
VSBYS...AND BRINGING CONDITIONS BACK TO VFR.

AT RME WITH A STRONG LL INVERSION WIND SHEAR LIKELY. SFC WINDS
UPVALLEY FROM THE SOUTHEAST WHILE ABOVE THE INVERSION AT 2K FT
THEY ARE SW AT 50 TO 70 KTS.

WINDS AT THE REST OF THE SITES NOW GUSTING. SOUTH WINDS AT 15 G 25
KTS. SYR IS 5 KTS STRONGER. WITH THE COLD FRONT TONIGHT A SHIFT TO
THE WEST AT SIMILAR SPEEDS. AROUND 11Z WEST WINDS INCREASE TO 20
TO 30 KTS WITH HIGHER GUSTS. AGAIN SYR WILL BE THE STRONGEST.

.OUTLOOK...

THU AFTN TO SAT NGT...OCNL MVFR TO IFR IN LAKE EFFECT SNOW
SHOWERS.

SUN...A COLD FRONT WITH MVFR AND IFR SNOW FOLLOWED BY MORE LAKE
EFFECT SNOW SUN NGT TO MONDAY.

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...FLOOD WATCH FROM 4 PM EST THIS AFTERNOON THROUGH THURSDAY
MORNING FOR PAZ038>040-043-044-047-048-072.
WIND ADVISORY FROM 7 PM THIS EVENING TO 7 PM EST THURSDAY FOR
PAZ038>040-043-044-047-048-072.
NY...FLOOD WATCH FROM 4 PM EST THIS AFTERNOON THROUGH THURSDAY
MORNING FOR NYZ009-015>018-022>025-036-037-044>046-
055>057-062.
WIND ADVISORY FROM 7 PM THIS EVENING TO 7 PM EST THURSDAY FOR
NYZ015-016-022>025-044-045-055-056-062.
HIGH WIND WARNING FROM 7 PM THIS EVENING TO 7 PM EST THURSDAY
FOR NYZ009-017-018-036-037-046-057.
LAKE EFFECT SNOW WATCH FROM THURSDAY MORNING THROUGH FRIDAY
MORNING FOR NYZ009.

$$
SYNOPSIS...
NEAR TERM...PVN
SHORT TERM...
LONG TERM...TAC
AVIATION...TAC
HYDROLOGY...TAC/JAB