Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/04/13

AREA FORECAST DISCUSSION

NWS DENVER/BOULDER CO

 256 PM MST WED JAN 2 2013

.SHORT TERM...WEB CAMS ACROSS MOUNTAINS STILL SHOWING AREAS OF
LIGHT SNOW CONFINED MAINLY TO THE CONTINENTAL DIVIDE OF SUMMIT AND
GRAND COUNTIES AS WELL AS PORTIONS OF THE GORE RANGE IN WESTERN
JACKSON COUNTY. THERE HAS BEEN A GRADUAL DECREASE IN THE LAST FEW
HOURS AS DRIER AND SLIGHTLY WARMER AIR SPREADS INTO THE REGION.
ACROSS PLAINS....ENOUGH MIXING ALLOWED NORTHWESTERLIES TO MIX TO
SURFACE...MAINLY NEAR THE WYOMING BORDER AND FAR EASTERN ZONES.
IN ADDITION...SURFACE ANTICYCLONE DEVELOPED NORTH OF DENVER WHICH
KEPT WINDS MORE NORTHERLY. LATEST RUC SHOWS ELONGATED UPPER TROUGH
CURRENTLY OVER COLORADO MOVING SOUTH DURING THE EVENING WITH FLOW
ALOFT BECOMING MORE NORTHERLY. DRIER SUBSIDENT AIR TO CONTINUE TO
MOVE ACROSS REGION...SHOULD SEE ANY LINGERING SNOW COME TO AN END
WITH CLEARING SKIES. THERE MAY BE A BATCH OF MID LEVEL CLOUD MOVE
ACROSS THE EASTERN PLAINS DURING THE EVENING. OTHERWISE...SKIES
TO GRADUALLY CLEAR BY MIDNIGHT. AS AIRMASS STABILIZES...SHOULD SEE
WINDS DECREASE ACROSS PLAINS BUT REMAIN A BIT GUSTY OVER THE
RIDGES. MODELS STILL HINTING A WEAK MOUNTAIN WAVE OVERNIGHT. BUT
FLOW ALOFT NOT THAT STRONG AND MORE NORTHERLY. COULD SEE SOME
GUSTS APPROACH 50 MPH IN FAVORED AREAS OF GRAND...JACKSON AND PARK
COUNTIES AFTER MIDNIGHT. WITH THE CLEARING SKIES AND THE PERSISTANT
INVERSIONS ALONG WITH LIGHTER WINDS...SHOULD SEE TEMPS DROP WELL
BELOW ZERO IN THE MOUNTAIN VALLEYS AS WELL AS LOW LYING AREAS
ACROSS THE PLAINS. DID LOWER MINS NEAR KREMMLING A FEW MORE
DEGREES TO ACCOUNT FOR THE CLEARING SKIES. ENOUGH DRAINAGE IN AND
NEAR FOOTHILLS TO KEEP TEMPS A BIT WARMER. ON THURSDAY...UPPER
TROUGH TO CONTINUE TO MOVE SOUTHEAST AS UPPER RIDGE BUILDS ACROSS
COLORADO FROM THE NORTHWEST. THIS WILL RESULT IN A NORTHEAST FLOW
ALOFT OVER THE REGION. CROSS SECTIONS INDICATE THE AIRMASS WILL BE
FAIRLY DRY WITH MAINLY HIGH LEVEL MOISTURE. TEMPERATURES TO BEGIN
TO MODERATE A BIT...THOUGH INVERSIONS WILL LIMIT WARMUP...
ESPECIALLY IN LOW LYING AREAS. HIGHS MAY STRUGGLE TO GET ABOVE
ZERO NEAR KREMMELING. TEMPERATURES ACROSS THE PLAINS SHOULD BE
MAINLY IN THE LOWER 30S...WITH MID TO UPPER 20S NEAR GREELEY.

.LONG TERM...THE CURRENT AMPLIFIED RIDGE/TROUGH PATTERN OVER THE
EASTERN PACIFIC AND WESTERN UNITED STATES WILL GRADUALLY WEAKEN
LATE THURSDAY INTO FRIDAY AS A FAST NORTHEASTWARD MOVING PACIFIC
THROUGH OF LOW PRESSURE ENTERS THE PAC NW COAST. THIS WILL WEAKEN
THE RIDGE OVER THE ROCKIES AND PROVIDE A FAIRLY DISORGANIZED FLOW
PATTERN OVER THE WESTERN HALF OF THE US INCLUDING NE COLO. AS THE
WEAKENING RIDGE MOVES EASTWARD AND FLATTENS...THE WARMEST MID
LEVEL TEMPS FOLD OVER ONTO THE CENTRAL ROCKIES AND WILL GIVE WAY
TO THE START OF WARMER TEMPERATURES EXPECTED IN THE EXTENDED WITH
TEMPS REBOUNDING TO NEAR TO ABOVE SEASONAL NORMALS.

BY LATE FRIDAY INTO SATURDAY...THE DISORGANIZED FLOW ALOFT OVER THE
ROCKIES GIVES WAY TO A VERY WEAK AND DRY UPPER LOW OVER THE OK
PANHANDLE. QG VERTICAL VELOCITY FIELDS INDICATE VERY LIGHT LIFT
ASSOC WITH THIS OVER NE CO AND WILL KEEP THE PERIOD DRY. THIS UPPER
LOW IS EVENTAULLY DRAWN INTO A ALBERTA CLIPPER-TYPE FEATURE DROPPING
OUT OF CANADA AND QUICKLY EVACUTES THE REGION TO THE NE US. WILL
NEED TO WATCH IN LATER RUNS IF THIS FAST DROPPING CANADIAN TROUGH
PUSHES A WEAK BUT DRY COLD FRONT/SURGE INTO EASTERN COLORADO FOR
LATE SATURDAY INTO SUNDAY. IF SO...ONLY TEMPS LOOK TO BE COOLED
SLIGHTLY FOR SUNDAY.

BY SUNDAY...UPPER RIDGE BECOMES FIRMLY REESTABLISHED OVER THE
ROCKIES AND CENTRAL US AS THE NEXT UPPER TROUGH APPROACHES THE CALI
COAST. TEMP GUIDANCE WOULD SUGGEST TEMPS WARMING TO ABOVE SEASONAL
NORMALS...MAINLY FOR THE LOWER ELEVATIONS AND AREAS WITHOUT A SOLID
SNOWPACK. STILL EXPECT MTN VALLEYS TO REMAIN COLD DURING THE NIGHT
PERIODS. LOOKING TOWARD MONDAY AND INTO THE MIDDLE OF NEXT
WEEK...GFS SWINGS ANOTHER FAST MOVING TROUGH OVER THE US/CAN BORDER
WHILE A SECOND COLD FRONT LOOKS TO CLIP THE NORTHERN AND EASTERN
PORTION OF COLO. AT THIS TIME FRONT LOOKS DRY. BEYOND MONDAY GFS
INDICATES VERY BENIGN DRY FLOW OVER THE STATE AS THE TROUGH OFF OF
THE CALI COAST DROPS AND WEAKENS INTO THE BAJA REGION. THIS PERIOD
ALSO REMAINS DRY WITH NO DISCERNABLE TEMP ADVECTION THROUGHOUT
ENTIRE ATMOS.

&&

.AVIATION...ANTICYCLONE NORTH OF THE DENVER AREA HAS KEPT
NORTHERLY WINDS AT DEN WITH NORTHEAST WINDS AT BJC AND APA. WINDS
HAVE BEEN A BIT GUSTY AT DEN...BUT ARE SHOWING SIGNS OF
DECREASING. WINDS TO CONTINUE TO WEAKEN ACROSS THE AREA AIRPORTS AND
BECOME MORE SOUTHEAST THROUGH 02Z...THEN SOUTHWEST BY 04Z AS
DRAINAGE PATTERN DEVELOPS. VFR TO PREVAIL WITH UNLIMITED CEILINGS.
A BATCH OF MID LEVEL CLOUD MAY MOVE ACROSS THE REGION DURING THE
EVENING WITH CEILINGS AROUND 10000 FEET FOR A SHORT TIME. ON
THURSDAY...SOUTHERLY WINDS TO PREVAIL WITH SPEEDS LESS THAN 10
KTS. WINDS COULD TREND TOWARD THE SOUTHEAST AT DEN AND APA DURING
THE AFTERNOON. VFR TO CONTINUE.

&&

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

$$

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




AREA FORECAST DISCUSSION

NWS GRAND JUNCTION CO

 1022 AM MST WED JAN 2 2013

.UPDATE...
ISSUED AT 1020 AM MST WED JAN 2 2013

LOW STRATUS UP TO ABOUT 600MB/-21C CONTINUES TO PRODUCE LIGHT SNOW
IN THE AREA EAST OF CRAIG. THE 15Z RAP HOLDS ONTO LIGHT SNOW THERE
TO MID AFTERNOON. ELSEWHERE FOG IS SLOSHING AROUND THE UINTAH
BASIN WITH PATCHY FOG REPORTED ALONG THE RIVER IN THE GRAND
VALLEY. OTHERWISE SUNNY BEAUTIFUL SKIES DOMINATE. STRONG
INVERSIONS WILL CONTINUE. THE LOW TEMPERATURE THIS MORNING AT THE
GRAND JUNCTION AIRPORT -6F...AT SKYWAY AT 10,600FT ON THE GRAND
MESA...-5F.

&&

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 311 AM MST WED JAN 2 2013

SNOW BEING REPORTED AT THIS HOUR OVER STEAMBOAT SPRINGS...CRAIG
AND MEEKER IN RESPONSE TO SHORT WAVE. SATELLITE IMAGERY CLEARLY
SHOWS MID LEVEL CLOUDS MOVING ACROSS THE REGION EXTENDING AS FAR
WEST AS THE UTAH BORDER AND NOW REACHING THE SAN JUANS. TEMPS HAVE
RESPONDED BY STAYING WARMER THAN SEEN LAST FEW NIGHTS. CURRENT
FORECAST STILL CALLS FOR MANY SUB-ZERO LOWS AS CLOUDS DO APPEAR TO
BE BREAKING UP SOMEWHAT WHICH SHOULD CAUSE TEMPS TO DROP QUICKLY.
IF THIS PROVES TO BE FALSE THOUGH...AN UPDATE WILL BE NEEDED TO
BUMP UP LOW TEMPS. MODELS GENERALLY AGREE THAT PRECIP SHOULD END
BY 12Z FOR THE AREAS MENTIONED ABOVE BUT NOT SOLD ON IDEA SINCE
CROSS SECTIONS SHOW ENOUGH MOISTURE TO KEEP LIGHT SNOW GOING
THROUGH AT LEAST EARLY AFTERNOON. FOLLOWED PREVIOUS THINKING AND
STARTED LOWERING POPS AFTER NOON WITH HIGHEST ELEVATIONS SEEING
CONTINUED LIGHT SNOW SHOWERS AFTER THAT. ACCUMULATIONS WILL BE
LIGHT...WHICH LOOKS TO BE PANNING OUT AS SNOTELS ACROSS THE AREA
SHOW LITTLE IF ANY ACCUMULATION.

BY THIS EVENING...THE UPPER LEVEL TROUGH WILL HAVE SHIFTED
SOUTHWARD  AS AIRFLOW BECOMES MORE NORTHEAST TO NORTH. THIS FLOW
WILL KEEP TEMPERATURES ON THE COLD SIDE AND WITH PLENTY OF CLEAR
SKIES EXPECTED...TEMPERATURES WILL BOTTOM OUT YET AGAIN.

FOR THURSDAY...A RIDGE OF HIGH PRESSURE WILL BE OVER THE GREAT
BASIN  WHILE A CLOSED LOW WILL MOVE ACROSS NORTHERN MEXICO BEFORE
SHIFTING NORTHEASTWARD INTO NEW MEXICO. AS FAR AS THE RIDGE IS
CONCERNED...PIECES OF ENERGY APPROACHING THE PAC NW WILL CAUSE THE
RIDGE TO BREAK DOWN. HOWEVER...UTAH AND COLORADO WILL BE BETWEEN
THE LOW PRESSURE AND THIS RIDGE SO NO INCLEMENT WEATHER EXPECTED.
AS FAR AS OUR WEATHER IS CONCERNED THEN...PLENTY OF SUNSHINE ON
TAP WITH INVERSIONS REMAINING IN PLACE KEEPING VALLEY TEMPS WELL
BELOW NORMAL.

.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 311 AM MST WED JAN 2 2013

QUIET WEATHER WILL CONTINUE THROUGH THE REMAINDER OF THE WEEK...
THROUGH THE WEEKEND...AND INTO EARLY NEXT WEEK. MODELS HAVE COME
INTO MUCH BETTER AGREEMENT THIS MORNING INCREASING CONFIDENCE IN
A DRY FORECAST DURING THE MEDIUM RANGE PERIOD.

FROM THURSDAY NIGHT INTO FRIDAY...A SHORTWAVE MOVING OVER THE
NORTHERN TIER STATES WILL WIPE OUT THE RIDGE WHILE FORCING THE
CLOSED LOW CIRCULATION TO THE SOUTH TO EJECT TO THE PANHANDLE
REGION OF TEXAS. DRY AIR OVER THE FORECAST AREA BETWEEN THESE
SYSTEMS EFFECTIVELY ELIMINATES ANY CHANCE FOR SNOW.

THE RIDGE REDEVELOPS THIS WEEKEND AS A DIGGING SYSTEM MOVING OUT
OF THE ALASKAN GULF BECOMES ESTABLISHED OFF THE WEST COAST. THE
RIDGE AGAIN FLATTENS IN RESPONSE TO A SHORTWAVE MOVING ACROSS THE
NORTHERN STATES ON SUNDAY BUT THE AIR MASS WILL REMAIN VERY DRY
ACROSS THE WEST.

FROM MONDAY INTO TUESDAY A WEAK DEFORMATION REGION FORMS OVER THE
AREA AS THE NOW CLOSED LOW CIRCULATION OVER THE EASTERN PACIFIC
BEGINS TO MOVE INTO THE DESERT SOUTHWEST. HERE THE MODELS BEGIN TO
DIVERGE A BIT AS THE GFS BRINGS THE SYSTEM EASTWARD FASTER THAN
THE ECMWF. BY TUESDAY EVENING...THE GFS HAS THE MID LEVEL LOW
CENTERED OVER ARIZONA WHILE THE ECMWF HOLD THE LOW OFF THE
NORTHERN COAST OF BAJA. REGARDLESS...EVEN THE MORE PROGRESSIVE GFS
FAILS TO ADVECT ENOUGH MOISTURE TO GENERATE SHOWERS OVER THE AREA
UNTIL LATER IN THE WEEK.

TEMPERATURES MODERATE DURING THE EXTENDED PERIOD WITH 7H ISOTHERMS
RISING FROM THE -4 TO -8 DEC C RANGE FRIDAY TO 0 TO -2 DEG C BY
SUNDAY AND REMAINING STEADY INTO EARLY NEXT WEEK. AS A RESULT...
EXPECT MOUNTAIN AREAS TO EXPERIENCE SOME FAIRLY SIGNIFICANT
WARMING WHILE INVERTED VALLEYS WILL BE MUCH SLOWER TO WARM.
THEREFORE...CONTINUED TO UNDERCUT GUIDANCE FOR MOST LOWER
ELEVATION SITES.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY MORNING)
ISSUED AT 1020 AM MST WED JAN 2 2013

AREAS OF IFR FOG EXPECTED TO LIFT FROM KVEL AFT 20Z. ALSO MVFR TO
IFR CIGS EAST OF KCAG INCLUDING KHDN AND KSBS EXPECTED TO BECOME
AFT 21Z. OTHERWISE VFR CONDITIONS DOMINATE. BASIN FOG RETURNS AFT
06Z TONIGHT MAINLY AFFECTING KVEL.


&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&

$$

UPDATE...JOE
SHORT TERM...TGR
LONG TERM...NL
AVIATION...TGR







AREA FORECAST DISCUSSION

NWS PUEBLO CO

 1019 AM MST WED JAN 2 2013

.AVIATION...

KCOS AND KPUB...VFR CONDITIONS THROUGH THE NEXT 24 HOURS WITH
LIGHT DIURNALLY DRIVEN WINDS.

KALS...CIGS AND VIS HAVE IMPROVED AS FOG HAS DISSIPATED. EXPECT
VFR CONDITIONS BEYOND 19Z FOR THE REMAINDER OF THE AFTERNOON AND
EARLY EVENING. EXPECT FOG TO REDEVELOP AROUND 04Z TONIGHT AND
PERSIST INTO THURSDAY MORNING WITH IFR TO LIFR CONDITIONS.  MOZLEY

&&

.PREV DISCUSSION... /ISSUED 404 AM MST WED JAN 2 2013/

SHORT TERM...
(TODAY AND TONIGHT)

CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS IS INDICATING
MODERATE TO STRONG NORTHERLY FLOW ALOFT ACROSS THE REGION AS A
BROAD UPPER TROUGH PERSISTS ACROSS THE UPPER MIDWEST THROUGH THE
HIGH PLAINS AND A HIGH AMPLITUDE RIDGE IS IN PLACE ACROSS THE
WEST COAST AT THIS TIME. WATER VAPOR IMAGERY IS ALSO INDICATING
AN EMBEDDED SHORT WAVE TRANSLATING ACROSS THE NORTHERN ROCKIES
WITH MORE ENERGY DIVING DOWN THE BACK SIDE OF THE UPPER RIDGE
ACROSS WESTERN CANADA AT THIS TIME. REGIONAL SATELLITE AND RADAR
DATA INDICATING SOME MID LEVEL MOISTURE SPREADING SOUTHEAST ACROSS
NORTHERN COLORADO ALONG WITH A FEW ECHOES MOVING ACROSS NORTHEASTERN
COLORADO AND NORTHWESTERN KANSAS AT THIS TIME. SATELLITE DATA ALSO
INDICATING COLD TEMPERATURES ACROSS THE HIGH MT VALLEYS ALONG WITH
PATCHY FREEZING FOG.

TODAY...EMBEDDED NORTHERN ROCKIES SHORTWAVE CONTINUES TO
TRANSLATE INTO THE NORTHERN HIGH PLAINS WHICH SENDS A WEAK
BACKDOOR COLD FRONT ACROSS EASTERN COLORADO THIS MORNING AS SFC
HIGH PRESSURE BUILDS ACROSS THE HIGH PLAINS. GENERALLY WEAK
NORTHERLY WINDS ACROSS THE PLAINS THIS MORNING TO BECOME LIGHT
UPSLOPE THROUGH THE AFTERNOON AND WITH A COLD AIRMASS IN
PLACE...SHOULD SEE HIGHS AROUND YESTERDAYS READINGS. MODELS IN
GENERAL AGREEMENT WITH KEEPING PRECIPITATION MAINLY ACROSS
NORTHERN AND NORTHEASTERN COLORADO THIS MORNING...THOUGH HAVE KEPT
SLIGHT POPS ACROSS THE EASTERN SAWATCH RANGE NORTH OF COTTONWOOD
PASS. THE HI RES RAP MODEL HAS BEEN PRINTING OUT SOME LIGHT QPF
ACROSS PIKES PEAK AND THE SANGRE DE CRISTO MTS THIS AFTERNOON
WHICH SEEMS POSSIBLE WITH DEVELOPING LOW LEVEL UPSLOPE FLOW AND
CONTINUED COLD AIR ALOFT. AT ANY RATE...HAVE KEPT A DRY FORECAST
INTACT FOR THIS AFTERNOON THOUGH LATER SHIFTS WILL NEED TO
CONTINUE TO MONITOR FOR A FEW POSSIBLE SHOWERS.

TONIGHT...MODERATE NORTHERLY FLOW ALOFT CONTINUES AS NEXT EMBEDDED
WAVE DIGS ACROSS THE NORTHERN ROCKIES. MODELS CONTINUE TO KEEP THE
AREA DRY...THOUGH DO INDICATE SOME MID LEVEL MOISTURE SPREADING
ACROSS THE EASTERN PLAINS THROUGH THE EARLY MORNING HOURS. AGAIN
WITH THE COLD AIRMASS IN PLACE AND MOSTLY CLEAR SKIES THROUGH THE
EVENING HOURS...SHOULD SEE TEMPERATURES TANK AFTER SUNSET WITH SOME
POSSIBLE WARMING ACROSS THE EASTERN PLAINS INTO THE EARLY MORNING.
WITH THAT SAID...HAVE GONE AT OR BELOW THE COLDER SIDE OF GUIDANCE
ESPECIALLY ACROSS THE MTS AND HIGH MT VALLEYS. -MW

LONG TERM...
(THURSDAY THROUGH TUESDAY)

LATEST MODEL RUNS SHOW TROF AXIS LINGERING JUST TO OUR SOUTH
THURSDAY AS RIDGE AXIS NOSES INTO WY BY FRIDAY. MOISTURE AND
PRECIPITATION REMAIN WELL TO OUR SOUTH DURING THIS PERIOD WITH
TEMPERATURES WARMING THROUGH FRIDAY. SNOW COVERED AREAS WILL REMAIN
COOLER THAN THOSE LOCATIONS WITHOUT SNOW COVER.

NEXT SHORTWAVE MOVES OVER THE TOP OF THE RIDGE AND SOUTH THROUGH THE
HIGH PLAINS LATE FRIDAY NIGHT AND SATURDAY. AT THE SURFACE...A
COLD FRONT MOVES SOUTH THROUGH THE PLAINS SATURDAY...BUT LIMITED
MOISTURE KEEPS THE FORECAST DRY. TEMPERATURES WILL BE A BIT COOLER
EAST OF THE MOUNTAINS SATURDAY.

UPPER RIDGE AXIS RETURNS FOR SUNDAY AND MONDAY WITH TEMPERATURES
WARMING ONCE AGAIN FOR MOST LOCATIONS. SNOW COVER WILL CONTINUE TO
BE A FACTOR IN DAILY HIGH AND LOW TEMPERATURES. STRONG INVERSIONS
WILL STILL DEVELOP IN THE SAN LUIS VALLEY...KEEPING HIGHS IN THE
TEENS TO LOWER 20S AND LOWS IN THE TEENS AND 20S BELOW ZERO.

WHILE THE GFS HAS BEEN CONSISTENT THE PAST FEW RUNS SHOWING A
CLOSED LOW OFF THE SOUTHERN CALIFORNIA COAST BY EARLY NEXT WEEK
..ECMWF NOW ALSO DEPICTING THIS SOLUTION. STILL SOME DIFFERENCES
IN TIMING AND TRACK OF THIS SYSTEM WITH THE GFS WEAKER AND MORE
PROGRESSIVE WEDNESDAY INTO THURSDAY. THE TRACK SHOWS SOME
POTENTIAL FOR SNOW IN FAR SOUTHERN COLORADO NEXT WEDNESDAY...BUT
LATER SHIFTS WILL HAVE TO MONITOR MODELS TO FINE TUNE THE FORECAST
IN THE COMING DAYS.

40

AVIATION...
VFR CONDITIONS EXPECTED FOR THE NEXT 24 HOURS AT KCOS AND KPUB WITH
POSSIBLE MID LEVEL CIGS THIS AFTERNOON WITH DEVELOPING UPSLOPE LOW
LEVEL FLOW.

OCCASIONAL IFR AND LIFR CONDITIONS IN PATCHY FZFG TO PERSIST AT KALS
THROUGH 16Z WITH VFR CONDITIONS AND COLD TEMPERATURES EXPECTED THERE
AFTER. MODELS INDICATING SIMILAR CONDITIONS POSSIBLE AGAIN THIS
LATER EVENING...BUT NOT ENOUGH CONFIDENCE TO INCLUDE IN TAF AT THIS
TIME. -MW

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

88/50






AREA FORECAST DISCUSSION

NWS DENVER/BOULDER CO

 939 AM MST WED JAN 2 2013

.UPDATE...


&&

.SHORT TERM...LIGHT SNOW STILL PERSISTING ACROSS WASHINGTON AND
NORTHERN LINCOLN COUNTIES...SLOWLY TREKING SOUTH-SOUTHEAST. SOME
ECHOES UPSTREAM OVER WYOMING AND NEBRASKA. AREAS OF LIGHT SNOW
ALSO OCCURING ACROSS MOUNTAINS...MAINLY ALONG THE CONTINENTAL
DIVIDE...AS SHOWN BY WEB CAMS. PRECIP BEING GENERATED BY WEAK MID
LEVEL QG ASCENT ASSOCIATED WITH UPPER TROUGH CURRENTLY MOVING
ACROSS THE REGION. MODELS CONTINUE TO SHOW AIRMASS DRYING OUT THIS
AFTERNOON AS TROUGH MOVES AWAY FROM REGION AND SUBSIDENCE SPREADS
ACROSS THE AREA. AIRMASS TO REMAIN SLIGHTLY UNSTABLE THROUGH THE
AFTERNOON...SO THERE MAY STILL BE SOME LINGERING FLURRIES OVER THE
REGION DURING THE AFTERNOON. OVERALL CURRENT FORECASTS LOOK
REASONABLE...BUT DID KEEP A MENTION OF LIGHT SNOW ACROSS THE FAR
PLAINS THROUGH THE MORNING. WILL CONTINUE THE TREND OF DECREASING
CLOUDS. WILL LEAVE THE TEMPS AS IS FOR NOW...BUT MAY NEED TO MAKE
ADJUSTMENTS TO THE MIN TEMPS IF SKIES CLEAR SOONER THAN
ANTICIPITATED.

.AVIATION...WINDS MAINTAINING A SOUTHWEST DIRECTION AT AREA
AIRPORTS. LATEST RAP AND HRRR SUGGESTING THE DEVELOPMENT OF AN
ANTICYCLONE NORTH OF THE AREA WHICH WOULD SHIFT THE WINDS TO A
NORTHEAST DIRECTION DURING THE AFTERNOON. STILL SOME QUESTION
WHETHER WINDS WILL INITIALLY GO CLOCKWISE OR COUNTERCLOCKWISE. FOR
NOW WILL CONTINUE THE TREND OF THE CURRENT TAFS...WITH PERHAPS A
VARIABLE DIRECTION FOR AN HOUR OR SO BEFORE GOING NORTHEAST.
SPEEDS TO REMAIN BELOW 12 KTS. SLIGHT CHANCE OF CEILINGS AROUND
6000 FEET AGL FOR SHORT PERIODS DURING THE AFTERNOON. CONFIDENCE
TOO LOW TO INCLUDE IN THE TAF FOR NOW.


&&

.PREV DISCUSSION... /ISSUED 420 AM MST WED JAN 2 2013/

SHORT TERM...UPPER TROUGH WILL DROP ACROSS COLORADO TODAY AND
TONIGHT WITH FLOW ALOFT BECOMING NNE. DETAILS STILL MESSY...THERE
IS A WEAK TROUGH PASSING OUR AREA NOW WITH FAIRLY WIDESPREAD
FLURRIES ON THE PLAINS. THE MAIN TROUGH AXIS WITH THE COLDEST AIR
ALOFT APPEARS TO BE SCHEDULED FOR LATE AFTERNOON OR EARLY
EVENING...BUT THERE IS STILL SOME CLOUD COVER FOR A WAYS BEHIND
THAT AS THE WEAK INSTABILITY WILL GIVE WAY TO A LITTLE LIFT FROM
WARM ADVECTION...THEN SUBSIDENCE AND CLEARING COMING IN FROM THE
NORTH BY THURSDAY MORNING. CLOUD COVER AGAIN WILL BE
DIFFICULT...THERE IS LOTS OF CONVECTION UPSTREAM THOUGH IT IS WEAK
AND HIGH BASED AND HAS PLENTY OF HOLES IN IT AS WELL. THERE DOES
APPEAR TO BE STEADY DRYING...AND I WILL STICK WITH THE IDEA THAT
THIS WILL WIN OVER EVERYTHING ELSE WITH A GENERAL SLOW DECREASE
IN CLOUD COVER THROUGH THE DAY. STILL COULD BE A FEW FLAKES HERE
AND THERE...BUT AFTER THE NEXT COUPLE HOURS NOT WORTH MENTIONING
EXCEPT IN THE MOUNTAINS...AND EVEN THERE IT LOOKS LIKE DRYING FROM
THE WEST SHOULD SHUT THINGS DOWN THIS MORNING.

MAIN CHANGES WERE TO ACCOUNT FOR CURRENT CONDITIONS...WARMER AND
MOISTER ON THE NORTHEAST PLAINS...ALMOST A BACKDOOR WARM FRONT IF
THERE IS SUCH A THING. DENVER AREA WINDS LOOK TRICKY BUT MODEL
GUIDANCE SHOWS THE ANTICYCLONE PERSISTING WITH SOUTHERLY WINDS
OVER DENVER THROUGH THE DAY...SO WE WILL STICK WITH THAT IDEA AS
WELL. PROBABLY ENOUGH OF A WESTERLY COMPONENT STILL TO FORCE THE
TURNING...AND STILL A LITTLE LOW LEVEL STABILITY TO PREVENT MIXING
OVER DENVER AND MAINTAIN THE CIRCULATION. TWEAKED LOW TEMPERATURES
TONIGHT TOWARD THE LATEST GUIDANCE WHICH IS COLDER IN THE COLDEST
SPOTS. WHILE THERE WILL BE SOME CLOUDS BEHIND THE TROUGH AXIS FOR
A WHILE...EXPECT CLEARING IN THE NORTH AND WEST PARTS OF OUR AREA
BY MORNING...AND PROBABLY SOON ENOUGH TO ALLOW FOR TEMPERATURES TO
DROP. SOME CONCERN ABOUT EARLIER CLEARING THAT WOULD LET IT GET
COLDER...NAM MOS HAS -28 AT KREMMLING AND -13 AT GREELEY WHICH
MAY NOT BE COLD ENOUGH IF IT DOES CLEAR EARLY IN THE NIGHT. SHOULD
BE SOME DRAINAGE WIND IN USUAL SPOTS TO KEEP THE FOOTHILLS AND
DENVER WARMER...THOSE AREAS COULD EVEN BE WARMING OVERNIGHT
AGAIN. FINALLY...HINTS OF A NELY MOUNTAIN WAVE SETUP LATE TONIGHT
AS THE WARM ADVECTION SETS IN. FLOW NOT THAT STRONG AND MORE NLY
THAN NE...SO WOULD MAINLY AFFECT THE FAIRPLAY AREA AND MAYBE SOME
SPARSELY POPULATED SPOTS IN GRAND AND JACKSON COUNTIES...DO NOT
THINK THERE IS MUCH HIGH WIND THREAT BUT COULD BE POCKETS OF 50
MPH GUSTS WHERE THE TERRAIN IS SHAPED RIGHT.

LONG TERM...AN UPPER LEVEL RIDGE WILL BUILD INTO COLORADO FROM
THE NORTH AND WEST ON THURSDAY WITH A DRY NORTHEASTERLY FLOW ALOFT
OVER THE CWFA. THE FLOW ALOFT WILL REMAIN DRY ON FRIDAY WITH A
WEAK UPPER TROUGH PASSING TO THE SOUTH AND EAST. TEMPERATURES
WILL MODIFY TO NEAR SEASONAL NORMALS BY THAT TIME. THE FLOW ALOFT
WILL INCREASE AND BECOME NORTHWESTERLY FRIDAY NIGHT INTO SATURDAY
AS A WEAK UPPER LEVEL DISTURBANCES PASSES FROM THE NRN GREAT
PLAINS AND INTO THE MIDWEST. ONLY EFFECT FM THIS WILL BE A SLIGHT
DECREASE IN AFTN TEMPERATURES ON SATURDAY FOR THE NORTHEAST
PLAINS. OTHERWISE UPPER LEVEL RIDGING OVER THE WESTERN U.S WILL
KEEP THE AMS OVER COLORADO DRY AND STABLE. THE DRY PATTERN WILL
CONTINUE INTO EARLY NEXT WEEK. THE RIDGE WILL FLATTEN SOMEWHAT
WITH THE STORM TO THE NORTH OF COLORADO. AN EMBEDDED DISTURBANCE
IS POSSIBLE BUT OVERALL THE PATTERN STILL LOOKS QUITE BENIGN SO
WILL KEEP IT DRY.

AVIATION...VFR CONDITIONS WITH LIGHT WINDS TODAY. CEILINGS WILL
GENERALLY BE ABOVE 6000 FT AGL THOUGH THERE IS A CHANCE OF
SLIGHTLY LOWER CEILINGS FOR SHORT PERIODS. SOUTH WINDS WILL
PREVAIL THOUGH THERE IS SOME UNCERTAINTY ABOUT THE DIRECTION THIS
AFTERNOON...SPEEDS UNDER 12 KNOTS.

&&

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

$$

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




AREA FORECAST DISCUSSION

NWS PUEBLO CO

 404 AM MST WED JAN 2 2013

.SHORT TERM...
(TODAY AND TONIGHT)

CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS IS INDICATING
MODERATE TO STRONG NORTHERLY FLOW ALOFT ACROSS THE REGION AS A
BROAD UPPER TROUGH PERSISTS ACROSS THE UPPER MIDWEST THROUGH THE
HIGH PLAINS AND A HIGH AMPLITUDE RIDGE IS IN PLACE ACROSS THE
WEST COAST AT THIS TIME. WATER VAPOR IMAGERY IS ALSO INDICATING
AN EMBEDDED SHORT WAVE TRANSLATING ACROSS THE NORTHERN ROCKIES
WITH MORE ENERGY DIVING DOWN THE BACK SIDE OF THE UPPER RIDGE
ACROSS WESTERN CANADA AT THIS TIME. REGIONAL SATELLITE AND RADAR
DATA INDICATING SOME MID LEVEL MOISTURE SPREADING SOUTHEAST ACROSS
NORTHERN COLORADO ALONG WITH A FEW ECHOES MOVING ACROSS NORTHEASTERN
COLORADO AND NORTHWESTERN KANSAS AT THIS TIME. SATELLITE DATA ALSO
INDICATING COLD TEMPERATURES ACROSS THE HIGH MT VALLEYS ALONG WITH
PATCHY FREEZING FOG.

TODAY...EMBEDDED NORTHERN ROCKIES SHORTWAVE CONTINUES TO
TRANSLATE INTO THE NORTHERN HIGH PLAINS WHICH SENDS A WEAK
BACKDOOR COLD FRONT ACROSS EASTERN COLORADO THIS MORNING AS SFC
HIGH PRESSURE BUILDS ACROSS THE HIGH PLAINS. GENERALLY WEAK
NORTHERLY WINDS ACROSS THE PLAINS THIS MORNING TO BECOME LIGHT
UPSLOPE THROUGH THE AFTERNOON AND WITH A COLD AIRMASS IN
PLACE...SHOULD SEE HIGHS AROUND YESTERDAYS READINGS. MODELS IN
GENERAL AGREEMENT WITH KEEPING PRECIPITATION MAINLY ACROSS
NORTHERN AND NORTHEASTERN COLORADO THIS MORNING...THOUGH HAVE KEPT
SLIGHT POPS ACROSS THE EASTERN SAWATCH RANGE NORTH OF COTTONWOOD
PASS. THE HI RES RAP MODEL HAS BEEN PRINTING OUT SOME LIGHT QPF
ACROSS PIKES PEAK AND THE SANGRE DE CRISTO MTS THIS AFTERNOON
WHICH SEEMS POSSIBLE WITH DEVELOPING LOW LEVEL UPSLOPE FLOW AND
CONTINUED COLD AIR ALOFT. AT ANY RATE...HAVE KEPT A DRY FORECAST
INTACT FOR THIS AFTERNOON THOUGH LATER SHIFTS WILL NEED TO
CONTINUE TO MONITOR FOR A FEW POSSIBLE SHOWERS.

TONIGHT...MODERATE NORTHERLY FLOW ALOFT CONTINUES AS NEXT EMBEDDED
WAVE DIGS ACROSS THE NORTHERN ROCKIES. MODELS CONTINUE TO KEEP THE
AREA DRY...THOUGH DO INDICATE SOME MID LEVEL MOISTURE SPREADING
ACROSS THE EASTERN PLAINS THROUGH THE EARLY MORNING HOURS. AGAIN
WITH THE COLD AIRMASS IN PLACE AND MOSTLY CLEAR SKIES THROUGH THE
EVENING HOURS...SHOULD SEE TEMPERATURES TANK AFTER SUNSET WITH SOME
POSSIBLE WARMING ACROSS THE EASTERN PLAINS INTO THE EARLY MORNING.
WITH THAT SAID...HAVE GONE AT OR BELOW THE COLDER SIDE OF GUIDANCE
ESPECIALLY ACROSS THE MTS AND HIGH MT VALLEYS. -MW

.LONG TERM...
(THURSDAY THROUGH TUESDAY)

LATEST MODEL RUNS SHOW TROF AXIS LINGERING JUST TO OUR SOUTH
THURSDAY AS RIDGE AXIS NOSES INTO WY BY FRIDAY. MOISTURE AND
PRECIPITATION REMAIN WELL TO OUR SOUTH DURING THIS PERIOD WITH
TEMPERATURES WARMING THROUGH FRIDAY. SNOW COVERED AREAS WILL REMAIN
COOLER THAN THOSE LOCATIONS WITHOUT SNOW COVER.

NEXT SHORTWAVE MOVES OVER THE TOP OF THE RIDGE AND SOUTH THROUGH THE
HIGH PLAINS LATE FRIDAY NIGHT AND SATURDAY. AT THE SURFACE...A
COLD FRONT MOVES SOUTH THROUGH THE PLAINS SATURDAY...BUT LIMITED
MOISTURE KEEPS THE FORECAST DRY. TEMPERATURES WILL BE A BIT COOLER
EAST OF THE MOUNTAINS SATURDAY.

UPPER RIDGE AXIS RETURNS FOR SUNDAY AND MONDAY WITH TEMPERATURES
WARMING ONCE AGAIN FOR MOST LOCATIONS. SNOW COVER WILL CONTINUE TO
BE A FACTOR IN DAILY HIGH AND LOW TEMPERATURES. STRONG INVERSIONS
WILL STILL DEVELOP IN THE SAN LUIS VALLEY...KEEPING HIGHS IN THE
TEENS TO LOWER 20S AND LOWS IN THE TEENS AND 20S BELOW ZERO.

WHILE THE GFS HAS BEEN CONSISTENT THE PAST FEW RUNS SHOWING A
CLOSED LOW OFF THE SOUTHERN CALIFORNIA COAST BY EARLY NEXT WEEK
...ECMWF NOW ALSO DEPICTING THIS SOLUTION. STILL SOME DIFFERENCES
IN TIMING AND TRACK OF THIS SYSTEM WITH THE GFS WEAKER AND MORE
PROGRESSIVE WEDNESDAY INTO THURSDAY. THE TRACK SHOWS SOME
POTENTIAL FOR SNOW IN FAR SOUTHERN COLORADO NEXT WEDNESDAY...BUT
LATER SHIFTS WILL HAVE TO MONITOR MODELS TO FINE TUNE THE FORECAST
IN THE COMING DAYS.

STARK

&&

.AVIATION...
VFR CONDITIONS EXPECTED FOR THE NEXT 24 HOURS AT KCOS AND KPUB WITH
POSSIBLE MID LEVEL CIGS THIS AFTERNOON WITH DEVELOPING UPSLOPE LOW
LEVEL FLOW.

OCCASIONAL IFR AND LIFR CONDITIONS IN PATCHY FZFG TO PERSIST AT KALS
THROUGH 16Z WITH VFR CONDITIONS AND COLD TEMPERATURES EXPECTED THERE
AFTER. MODELS INDICATING SIMILAR CONDITIONS POSSIBLE AGAIN THIS
LATER EVENING...BUT NOT ENOUGH CONFIDENCE TO INCLUDE IN TAF AT THIS
TIME. -MW

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

23/40






AREA FORECAST DISCUSSION

NWS COLUMBIA SC

 446 AM EST WED JAN 2 2013

.SYNOPSIS...
A FRONT WILL SHIFT SOUTH THROUGH THE REGION THIS MORNING AND
STALL TO OUR SOUTH. A WEAK AREA OF LOW PRESSURE WILL RIDE EAST
ALONG THE FRONT JUST TO OUR SOUTH TONIGHT AND THURSDAY. HIGH
PRESSURE AND DRIER AIR WILL FILTER INTO THE REGION FRIDAY. A FRONT
IS EXPECTED TO MOVE THROUGH SUNDAY...FOLLOWED BY HIGH PRESSURE AND
FAIR WEATHER EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WSW UPPER FLOW OVER OUR REGION...WITH THE APPEARANCE OF AN UPPER
IMPULSE WHICH HAS PASSED BY AND IS MOVING OFF TO THE NE. CURRENT
SURFACE ANALYSIS INDICATES A FRONT STETCHED ACROSS THE REGION WITH
BROAD LOW PRESSURE OVER THE CAROLINAS. RADAR MOSAIC CURRENTLY
INDICATES AREAS OF LIGHT RAIN AND DRIZZLE OVER THE CAROLINAS...THE
AREAL COVERAGE OF WHICH HAS DECREASED MARKEDLY IN THE LAST FEW
HOURS BEHIND THE SHORTWAVE. THE LOW WILL QUICKLY TRACK EAST THIS
MORNING...WITH THE FRONT SHIFTING SOUTH TO THE COAST BY
AFTERNOON...AND STALLING TO OUR SOUTH...LEAVING AN INVERTED
SURFACE TROUGH OVER THE FA. MODELS INDICATE THE BULK OF
PRECIPITATION WILL MOVE OUT OF OUR FA EARLY THIS MORNING...WITH
LINGERING CLOUDINESS AND PATCHY LIGHT RAIN OR DRIZZLE LINGERING
OVER OUR FA.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
A WSW UPPER FLOW WILL CONTINUE TONIGHT INTO THURSDAY...WITH A
SERIES OF UPPER IMPULSES RIDING ACROSS THE REGION. MODELS MAINTAIN
STALLED FRONT TO OUR SOUTH...WITH INVERTED TROUGH REMAINING OVER
OUR FA TONIGHT. A WAVE OF LOW PRESSURE WILL RIDE EAST ALONG THE
FRONT TONIGHT AND EARLY THURSDAY...THAT WILL SPREAD SOME LIGHT
RAIN BACK INTO THE REGION.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
BEHIND THE IMPULSES...THE UPPER FLOW WILL BECOME MORE WESTERLY LATE
THURSDAY AND FRIDAY...ALLOWING HIGH PRESSURE AND DRIER AIR TO FILTER
INTO OUR REGION. UPPER TROUGHINESS WILL REDEVELOP OVER THE
CENTRAL CONUS LATE FRIDAY INTO SATURDAY...AND SHIFT EAST INTO THE
EASTERN CONUS SUNDAY. SURFACE HIGH OVER OUR REGION WILL WEAKEN AND
SHIFT EAST SAT NT/SUN AS A FRONT PUSHES THROUGH SUN/SUN NT. SOME
QUESTIONS REGARDING MOISTURE AVAILABILITY WITH THIS FRONT. LARGE
SPREAD IN GFS ENSEMBLE MOS POP NUMBERS...WITH AVERAGE POP AROUND
20...GENERALLY IN LINE WITH EXPERIMENTAL ECMWF MOS POPS. ONGOING
FORECAST FOR OUR FA AND SURROUNDING DOMAINS CURRENTLY ADVERTISING
POPS LESS THAN 20. LATER MODEL RUNS WILL HAVE TO BE EXAMINED FOR
THE POSSIBILITY OF INTRODUCING POPS FOR THIS TIME PERIOD. HIGH
PRESSURE WILL BUILD IN BEHIND THE FRONT MON/TUE.

&&

.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
A WEAK COLD FRONT WILL SLIDE SOUTH OF THE TAF SITES BY 12Z
THIS MORNING WITH WEDGE CONDITIONS AND IFR-MVFR CEILINGS 12Z-16Z.
WEAK SHORT WAVE MOVED EAST THIS MORNING AND LOCAL RADARS ARE
SHOWING THAT RAIN COVERAGE HAS ALSO DECREASED. PATCHY LIGHT
RAIN OR DRIZZLE MAY AFFECT TAF SITES THROUGH 14Z-15Z WITH MVFR
VSBYS POSSIBLE. 13KM RUC MODEL SHOWS PRECIPITATION SHOULD HAVE
MOVE EAST BY 15Z. MODELS BRING DRIER TO THE FORECAST AREA BY
18Z...SO EXPECT VFR CONDITIONS FOR MOST OF THE AFTERNOON. VFR
CONDITIONS WILL CONTINUE THIS EVENING.

EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE THURSDAY AS A
FRONTAL SYSTEM IS IN THE VICINITY.

&&

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

$$







AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 321 AM CST WED JAN 2 2013

.DISCUSSION...
811 PM CST

FOR EVENING UPDATE...

HAVE TWEAKED GOING FORECAST FOR TONIGHT MAINLY TO LOWER MIN TEMPS
1-3 DEGREES MOST AREAS AND ESPECIALLY NORTHWEST...AND TO INCREASE
SKY COVER AFTER MIDNIGHT ACROSS THE FAR NORTH.

EARLY EVENING ANALYSIS PLACES SURFACE HIGH PRESSURE FROM THE
SOUTHERN PLAINS INTO THE MID-MISSISSIPPI RIVER VALLEY. NORTHEAST
EXTENT OF SURFACE RIDGE AXIS EXTENDS INTO NORTHERN IL...WHERE CLEAR
SKIES WERE ALLOWING STRONG RADIATIONAL COOLING AS WINDS DECOUPLE
IN/NEAR THE RIDGE AXIS. BASED ON THESE TRENDS HAVE LOWERED TEMPS
ACROSS MUCH OF THE AREA BY UP TO SEVERAL DEGREES...CLOSER TO SOME
OF THE COOLER MOS GUIDANCE FROM 12/18Z.

OTHER FACTOR OF NOTE THIS EVENING IS THE AREA OF STRATUS OVER MUCH
OF THE UPPER MISSISSIPPI VALLEY...WHICH HAS BEEN DRIFTING EAST
DURING THE LATE AFTERNOON AND EARLY EVENING HOURS. STOUT LOW LEVEL
INVERSION ASSOCIATED WITH MODIFIED-ARCTIC AIR AND DENSE SNOW PACK
ACROSS AREAS WEST/NORTHWEST OF THE CWA WAS NOTED IN 12Z RAOBS FROM
UPSTREAM LOCATIONS. 21-00Z RAP FORECASTS OF 950-900 MB LAYER RH SEEM
TO CAPTURE THE EXTENT OF THE STRATUS FAIRLY WELL...AND SUGGEST THAT
THESE CLOUDS WILL SPREAD EAST INTO FAR NORTHERN IL AFTER MIDNIGHT
AND PERHAPS EVEN SHIFT A LITTLE SOUTHEAST THROUGH EARLY WEDNESDAY
MORNING. OTHER GUIDANCE HAS NOT HANDLED THE EXTENT/ADVECTION OF THE
STRATUS VERY WELL. BASED ON SATELLITE TRENDS AND THE RAP
FORECASTS...WHICH SEEM REASONABLE GIVEN THIS MOISTURE TRAPPED WITHIN
STABLE LOW LEVELS...HAVE INCREASED CLOUD COVER OVER FAR NORTHERN IL
LATE TONIGHT INTO EARLY WEDNESDAY. HOURLY TEMP GRIDS HAVE ALSO BEEN
ADJUSTED TO SHOW A CONTINUED DECLINE UNDER CLEAR SKIES...THEN REMAIN
FAIRLY STEADY OR EVEN RISE A DEGREE OR TWO FAR NORTH AS THE CLOUDS
MOVE IN. CONFIDENCE IN EXTENT/COVERAGE OF STRATUS DECREASES WITH
TIME...SO HAVE MAINTAINED PARTLY CLOUDY SKIES WEDNESDAY...THOUGH
WOULD NOT BE SURPRISED TO SEE CLOUDS LINGER ACROSS AT LEAST THE FAR
NORTHEAST PARTS OF THE FA THROUGH A PART OF WEDNESDAY MORNING.

RATZER

//PREV DISCUSSION...
300 PM CST

AN ACTIVE PATTERN IN THE NORTHERN STREAM WILL PROVIDE SOME UPS AND
DOWNS WITH TEMPERATURES FOR THE NEXT WEEK BUT VIRTUALLY NO CHANCE OF
ANY DROUGHT RELIEF.

TONIGHT-WEDNESDAY
MAIN CONCERNS FOR OVERNIGHT INTO WEDNESDAY ARE TEMPERATURE AND CLOUD
TRENDS. AREA OF STRATUS ACROSS MN-NORTHERN IA-WESTERN WIS. THIS
HAS BEEN ADVECTING EAST BUT LAST FEW VISIBLE SATELLITE IMAGES SHOW
SOUTHERN EDGE OF CLOUD DECK ERODING SLIGHTLY. THEREFORE THINK
STRATUS WILL STAY MAINLY N OF IL...POSSIBLY JUST CLIPPING FAR
NORTHERN COUNTIES AFTER MIDNIGHT. DESPITE WARM AIR ADVECTION
ALOFT...EXPECT ATMOSPHERE TO DECOUPLE THIS EVENING. SHOULD BE
GOOD RADIATIONAL COOLING WITH COLDEST TEMPS FAR NORTHWEST AND FAR
SOUTH WHERE SNOW COVER IS IN PLACE. STRATUS COULD HAVE SOME MINOR
IMPACT ON TEMPERATURES LATE TONIGHT NEAR THE WISCONSIN
LINE...POSSIBLY BECOMING STEADY OR RISING A BIT TOWARD DAYBREAK.
SOME SUNSHINE AND STRONG WARM AIR ADVECTION AHEAD OF APPROACHING
CLIPPER WEDNESDAY SHOULD PUSH TEMPERATURES ABOVE
GUIDANCE...ESPECIALLY IN LARGE SNOWLESS AREA FROM LASALLE COUNTY
TO CHICAGO. CONFIDENCE HIGH.

WEDNESDAY NIGHT-THURSDAY
CLIPPER MOVES FROM CENTRAL CANADA TO THE NORTHERN GREAT LAKES
WEDNESDAY NIGHT AND THURSDAY. SYSTEM MOVING INTO A VERY DRY AIR MASS
AND BEST DYNAMICS WELL NORTH OF THE LOCAL AREA...THEREFORE ONLY
EXPECT FLURRIES OR VERY LIGHT SNOW...WITH ONLY ABOUT A 20 PERCENT
CHANCE OF MEASURABLE PRECIP GENERALLY NORTH OF I-80. FLURRIES MAY
CONTINUE INTO THURSDAY IN COLD CYCLONIC FLOW. TEMPERATURES SHOULDN`T
FALL MUCH WEDNESDAY NIGHT UNDER STRONG SOUTHWEST FLOW AND INCREASING
CLOUD COVER. THEN TURNING BLUSTERY AND COLDER FOR THURSDAY.
CONFIDENCE HIGH.

FRIDAY-MONDAY
STRONG WARM AIR ADVECTION RETURNS FRIDAY AHEAD OF NEXT CLIPPER. THIS
SYSTEMS LOOKS TO BE EVEN MILDER THAN WEDNESDAY WITH 850 TEMPS OF +2
TO +4. AGAIN WILL TREND ABOVE GUIDANCE ESPECIALLY FOR AREAS WITH NO
SNOW COVER. SHOULD BE NEAR OR ABOVE FREEZING FRIDAY AND MID 30S BY
SATURDAY. ONLY SLIGHTLY COOLER SUNDAY BEHIND THE CLIPPER. AGAIN
NO PRECIP EXPECTED WITH SATURDAYS CLIPPER. MILD DRY PATTERN
CONTINUES FOR THE FIRST PART OF NEXT WEEK WITH TEMPERATURES IN THE
UPPER 30S AND POSSIBLY TAGGING 40. CONFIDENCE MEDIUM-HIGH.

ALLSOPP

&&

.AVIATION...

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

* MVFR CIGS MAINLY OVER 2000FT HAVE MOVED INTO THE AREA ALONG THE
  IL/WI LINE...AND SOME LOWER AREAS ARE NOT FAR AWAY...BUT ONLY
  RFD AND ORD SEEM POISED TO SEE THESE LOWER CONDITIONS.

LENNING

//DISCUSSION...UPDATED 09Z...

THE AREA OF LOWER CLOUDS HAS MOVED INTO BOTH RFD AND ORD BUT NOT
YET INTO MDW OR DPA. STILL COULD SEE SOME LOWER CONDITIONS TO
AROUND 2000FT.

STILL EXPECTING WINDS TO START VERY LIGHT FROM THE WEST OR
WEST NORTHWEST AND GRADUALLY TURN TO THE SOUTHWEST TODAY...NEVER
GETTING ESPECIALLY STRONG.

FLURRIES OR LIGHT SNOW ARE POSSIBLE WEDNESDAY NIGHT INTO THURSDAY.

LENNING

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

* MEDIUM CONFIDENCE IN CEILING TRENDS THIS MORNING.

LENNING

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

* THURSDAY...OCCASIONAL FLURRIES. MVFR POSSIBLE.
* FRIDAY THROUGH MONDAY...DRY. VFR.

&&

.MARINE...
242 AM CST

SPENT QUITE A BIT OF TIME OVERNIGHT TRYING TO GET THE WIND TRENDS
RIGHT OVER THE NEXT THREE DAYS. STILL NOT SURE THEY ARE RIGHT. THE
PRESSURE GRADIENT TIGHTENS TODAY AHEAD OF A FAST MOVING LOW
PRESSURE CLIPPER SYSTEM OVER THE NORTHERN PART OF THE LAKES.
HOWEVER...MILDER SOUTHWESTERLY WINDS AHEAD OF THIS SYSTEM MAY NOT
MIX DOWN AS WELL AS REALLY COLD WINDS WOULD BE EXPECTED TO. AFTER
THE CLIPPER MOVES NORTHEAST OF THE LAKE ON THURSDAY...WINDS TURN
WEST OR NORTHWEST AND THE COLDER AIR AND BETTER MIXING RETURNS
OVER THE WARMER LAKE WATER. EVEN SO...TEMPERATURES ABOVE THE COLD
SURFACE LAYER ARE FORECAST TO BE QUITE A BIT WARMER...INHIBITING
THE ABILITY TO TAP INTO STRONGER WINDS ALOFT. BY THURSDAY NIGHT
INTO FRIDAY A BROAD HIGH PRESSURE CENTER BUILDS ACROSS THE PLAINS
AND FURTHER INCREASES THE GRADIENT AGAINST A LOW OVER QUEBEC.
ORIGINALLY WAS THINKING THERE COULD BE PERIODS OF GALES ON
THURSDAY AND FRIDAY...BUT NOW AM NOT AS SURE. THE BEST CHANCE
WOULD APPEAR TO BE THURSDAY NIGHT INTO FRIDAY. OVERALL HAVE
LOWERED WIND SPEEDS JUST A BIT THROUGH THE FIRST THREE DAYS
COMPARED TO EARLIER THINKING.

LENNING

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 4 AM WEDNESDAY.

&&

$$






AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 305 AM CST WED JAN 2 2013

.DISCUSSION...
811 PM CST

FOR EVENING UPDATE...

HAVE TWEAKED GOING FORECAST FOR TONIGHT MAINLY TO LOWER MIN TEMPS
1-3 DEGREES MOST AREAS AND ESPECIALLY NORTHWEST...AND TO INCREASE
SKY COVER AFTER MIDNIGHT ACROSS THE FAR NORTH.

EARLY EVENING ANALYSIS PLACES SURFACE HIGH PRESSURE FROM THE
SOUTHERN PLAINS INTO THE MID-MISSISSIPPI RIVER VALLEY. NORTHEAST
EXTENT OF SURFACE RIDGE AXIS EXTENDS INTO NORTHERN IL...WHERE CLEAR
SKIES WERE ALLOWING STRONG RADIATIONAL COOLING AS WINDS DECOUPLE
IN/NEAR THE RIDGE AXIS. BASED ON THESE TRENDS HAVE LOWERED TEMPS
ACROSS MUCH OF THE AREA BY UP TO SEVERAL DEGREES...CLOSER TO SOME
OF THE COOLER MOS GUIDANCE FROM 12/18Z.

OTHER FACTOR OF NOTE THIS EVENING IS THE AREA OF STRATUS OVER MUCH
OF THE UPPER MISSISSIPPI VALLEY...WHICH HAS BEEN DRIFTING EAST
DURING THE LATE AFTERNOON AND EARLY EVENING HOURS. STOUT LOW LEVEL
INVERSION ASSOCIATED WITH MODIFIED-ARCTIC AIR AND DENSE SNOW PACK
ACROSS AREAS WEST/NORTHWEST OF THE CWA WAS NOTED IN 12Z RAOBS FROM
UPSTREAM LOCATIONS. 21-00Z RAP FORECASTS OF 950-900 MB LAYER RH SEEM
TO CAPTURE THE EXTENT OF THE STRATUS FAIRLY WELL...AND SUGGEST THAT
THESE CLOUDS WILL SPREAD EAST INTO FAR NORTHERN IL AFTER MIDNIGHT
AND PERHAPS EVEN SHIFT A LITTLE SOUTHEAST THROUGH EARLY WEDNESDAY
MORNING. OTHER GUIDANCE HAS NOT HANDLED THE EXTENT/ADVECTION OF THE
STRATUS VERY WELL. BASED ON SATELLITE TRENDS AND THE RAP
FORECASTS...WHICH SEEM REASONABLE GIVEN THIS MOISTURE TRAPPED WITHIN
STABLE LOW LEVELS...HAVE INCREASED CLOUD COVER OVER FAR NORTHERN IL
LATE TONIGHT INTO EARLY WEDNESDAY. HOURLY TEMP GRIDS HAVE ALSO BEEN
ADJUSTED TO SHOW A CONTINUED DECLINE UNDER CLEAR SKIES...THEN REMAIN
FAIRLY STEADY OR EVEN RISE A DEGREE OR TWO FAR NORTH AS THE CLOUDS
MOVE IN. CONFIDENCE IN EXTENT/COVERAGE OF STRATUS DECREASES WITH
TIME...SO HAVE MAINTAINED PARTLY CLOUDY SKIES WEDNESDAY...THOUGH
WOULD NOT BE SURPRISED TO SEE CLOUDS LINGER ACROSS AT LEAST THE FAR
NORTHEAST PARTS OF THE FA THROUGH A PART OF WEDNESDAY MORNING.

RATZER

//PREV DISCUSSION...
300 PM CST

AN ACTIVE PATTERN IN THE NORTHERN STREAM WILL PROVIDE SOME UPS AND
DOWNS WITH TEMPERATURES FOR THE NEXT WEEK BUT VIRTUALLY NO CHANCE OF
ANY DROUGHT RELIEF.

TONIGHT-WEDNESDAY
MAIN CONCERNS FOR OVERNIGHT INTO WEDNESDAY ARE TEMPERATURE AND CLOUD
TRENDS. AREA OF STRATUS ACROSS MN-NORTHERN IA-WESTERN WIS. THIS
HAS BEEN ADVECTING EAST BUT LAST FEW VISIBLE SATELLITE IMAGES SHOW
SOUTHERN EDGE OF CLOUD DECK ERODING SLIGHTLY. THEREFORE THINK
STRATUS WILL STAY MAINLY N OF IL...POSSIBLY JUST CLIPPING FAR
NORTHERN COUNTIES AFTER MIDNIGHT. DESPITE WARM AIR ADVECTION
ALOFT...EXPECT ATMOSPHERE TO DECOUPLE THIS EVENING. SHOULD BE
GOOD RADIATIONAL COOLING WITH COLDEST TEMPS FAR NORTHWEST AND FAR
SOUTH WHERE SNOW COVER IS IN PLACE. STRATUS COULD HAVE SOME MINOR
IMPACT ON TEMPERATURES LATE TONIGHT NEAR THE WISCONSIN
LINE...POSSIBLY BECOMING STEADY OR RISING A BIT TOWARD DAYBREAK.
SOME SUNSHINE AND STRONG WARM AIR ADVECTION AHEAD OF APPROACHING
CLIPPER WEDNESDAY SHOULD PUSH TEMPERATURES ABOVE
GUIDANCE...ESPECIALLY IN LARGE SNOWLESS AREA FROM LASALLE COUNTY
TO CHICAGO. CONFIDENCE HIGH.

WEDNESDAY NIGHT-THURSDAY
CLIPPER MOVES FROM CENTRAL CANADA TO THE NORTHERN GREAT LAKES
WEDNESDAY NIGHT AND THURSDAY. SYSTEM MOVING INTO A VERY DRY AIR MASS
AND BEST DYNAMICS WELL NORTH OF THE LOCAL AREA...THEREFORE ONLY
EXPECT FLURRIES OR VERY LIGHT SNOW...WITH ONLY ABOUT A 20 PERCENT
CHANCE OF MEASURABLE PRECIP GENERALLY NORTH OF I-80. FLURRIES MAY
CONTINUE INTO THURSDAY IN COLD CYCLONIC FLOW. TEMPERATURES SHOULDN`T
FALL MUCH WEDNESDAY NIGHT UNDER STRONG SOUTHWEST FLOW AND INCREASING
CLOUD COVER. THEN TURNING BLUSTERY AND COLDER FOR THURSDAY.
CONFIDENCE HIGH.

FRIDAY-MONDAY
STRONG WARM AIR ADVECTION RETURNS FRIDAY AHEAD OF NEXT CLIPPER. THIS
SYSTEMS LOOKS TO BE EVEN MILDER THAN WEDNESDAY WITH 850 TEMPS OF +2
TO +4. AGAIN WILL TREND ABOVE GUIDANCE ESPECIALLY FOR AREAS WITH NO
SNOW COVER. SHOULD BE NEAR OR ABOVE FREEZING FRIDAY AND MID 30S BY
SATURDAY. ONLY SLIGHTLY COOLER SUNDAY BEHIND THE CLIPPER. AGAIN
NO PRECIP EXPECTED WITH SATURDAYS CLIPPER. MILD DRY PATTERN
CONTINUES FOR THE FIRST PART OF NEXT WEEK WITH TEMPERATURES IN THE
UPPER 30S AND POSSIBLY TAGGING 40. CONFIDENCE MEDIUM-HIGH.

ALLSOPP

&&

.AVIATION...

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

* MVFR CIGS SEEM TO BE ON THE WAY...AND IF THEY MAKE IT INTO THE
  TERMINALS...MAY END UP STICKING AROUND A WHILE.

LENNING

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

HAVE BEEN TRACKING AN AREA OF LOWER CLOUDS SINCE LAST EVENING.
THIS HAS MOVED INTO NW IL AND LIKELY WILL BE INTO RFD WITHIN AN
HOUR OR SO. WHETHER IT GETS TO ORD IS LESS CERTAIN...AND INTO MDW
EVEN MORE UNCERTAIN. ELECTED TO KEEP THE SAME TIMING AS PREVIOUS
TAFS...BUT INCREASED COVERAGE FROM SCT TO BKN AT ORD.

WINDS START VERY LIGHT FROM THE WEST OR NORTHWEST AND GRADUALLY
TURN TO THE SOUTHWEST TODAY...NEVER GETTING ESPECIALLY STRONG.

FLURRIES OR LIGHT SNOW ARE POSSIBLE WEDNESDAY NIGHT INTO THURSDAY.

LENNING

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

* ONLY MEDIUM CONFIDENCE IN CIG TRENDS...BUT HIGHER CONFIDENCE
  THEY WILL AT LEAST STAY ABOVE IFR AND RANGE FROM 1500 TO 2500 FT.

LENNING

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

* THURSDAY...OCCASIONAL FLURRIES. MVFR POSSIBLE.
* FRIDAY THROUGH MONDAY...DRY. VFR.

&&

.MARINE...
242 AM CST

SPENT QUITE A BIT OF TIME OVERNIGHT TRYING TO GET THE WIND TRENDS
RIGHT OVER THE NEXT THREE DAYS. STILL NOT SURE THEY ARE RIGHT. THE
PRESSURE GRADIENT TIGHTENS TODAY AHEAD OF A FAST MOVING LOW
PRESSURE CLIPPER SYSTEM OVER THE NORTHERN PART OF THE LAKES.
HOWEVER...MILDER SOUTHWESTERLY WINDS AHEAD OF THIS SYSTEM MAY NOT
MIX DOWN AS WELL AS REALLY COLD WINDS WOULD BE EXPECTED TO. AFTER
THE CLIPPER MOVES NORTHEAST OF THE LAKE ON THURSDAY...WINDS TURN
WEST OR NORTHWEST AND THE COLDER AIR AND BETTER MIXING RETURNS
OVER THE WARMER LAKE WATER. EVEN SO...TEMPERATURES ABOVE THE COLD
SURFACE LAYER ARE FORECAST TO BE QUITE A BIT WARMER...INHIBITING
THE ABILITY TO TAP INTO STRONGER WINDS ALOFT. BY THURSDAY NIGHT
INTO FRIDAY A BROAD HIGH PRESSURE CENTER BUILDS ACROSS THE PLAINS
AND FURTHER INCREASES THE GRADIENT AGAINST A LOW OVER QUEBEC.
ORIGINALLY WAS THINKING THERE COULD BE PERIODS OF GALES ON
THURSDAY AND FRIDAY...BUT NOW AM NOT AS SURE. THE BEST CHANCE
WOULD APPEAR TO BE THURSDAY NIGHT INTO FRIDAY. OVERALL HAVE
LOWERED WIND SPEEDS JUST A BIT THROUGH THE FIRST THREE DAYS
COMPARED TO EARLIER THINKING.

LENNING

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 4 AM WEDNESDAY.

&&

$$








AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 1151 PM CST TUE JAN 1 2013

.DISCUSSION...
811 PM CST

FOR EVENING UPDATE...

HAVE TWEAKED GOING FORECAST FOR TONIGHT MAINLY TO LOWER MIN TEMPS
1-3 DEGREES MOST AREAS AND ESPECIALLY NORTHWEST...AND TO INCREASE
SKY COVER AFTER MIDNIGHT ACROSS THE FAR NORTH.

EARLY EVENING ANALYSIS PLACES SURFACE HIGH PRESSURE FROM THE
SOUTHERN PLAINS INTO THE MID-MISSISSIPPI RIVER VALLEY. NORTHEAST
EXTENT OF SURFACE RIDGE AXIS EXTENDS INTO NORTHERN IL...WHERE CLEAR
SKIES WERE ALLOWING STRONG RADIATIONAL COOLING AS WINDS DECOUPLE
IN/NEAR THE RIDGE AXIS. BASED ON THESE TRENDS HAVE LOWERED TEMPS
ACROSS MUCH OF THE AREA BY UP TO SEVERAL DEGREES...CLOSER TO SOME
OF THE COOLER MOS GUIDANCE FROM 12/18Z.

OTHER FACTOR OF NOTE THIS EVENING IS THE AREA OF STRATUS OVER MUCH
OF THE UPPER MISSISSIPPI VALLEY...WHICH HAS BEEN DRIFTING EAST
DURING THE LATE AFTERNOON AND EARLY EVENING HOURS. STOUT LOW LEVEL
INVERSION ASSOCIATED WITH MODIFIED-ARCTIC AIR AND DENSE SNOW PACK
ACROSS AREAS WEST/NORTHWEST OF THE CWA WAS NOTED IN 12Z RAOBS FROM
UPSTREAM LOCATIONS. 21-00Z RAP FORECASTS OF 950-900 MB LAYER RH SEEM
TO CAPTURE THE EXTENT OF THE STRATUS FAIRLY WELL...AND SUGGEST THAT
THESE CLOUDS WILL SPREAD EAST INTO FAR NORTHERN IL AFTER MIDNIGHT
AND PERHAPS EVEN SHIFT A LITTLE SOUTHEAST THROUGH EARLY WEDNESDAY
MORNING. OTHER GUIDANCE HAS NOT HANDLED THE EXTENT/ADVECTION OF THE
STRATUS VERY WELL. BASED ON SATELLITE TRENDS AND THE RAP
FORECASTS...WHICH SEEM REASONABLE GIVEN THIS MOISTURE TRAPPED WITHIN
STABLE LOW LEVELS...HAVE INCREASED CLOUD COVER OVER FAR NORTHERN IL
LATE TONIGHT INTO EARLY WEDNESDAY. HOURLY TEMP GRIDS HAVE ALSO BEEN
ADJUSTED TO SHOW A CONTINUED DECLINE UNDER CLEAR SKIES...THEN REMAIN
FAIRLY STEADY OR EVEN RISE A DEGREE OR TWO FAR NORTH AS THE CLOUDS
MOVE IN. CONFIDENCE IN EXTENT/COVERAGE OF STRATUS DECREASES WITH
TIME...SO HAVE MAINTAINED PARTLY CLOUDY SKIES WEDNESDAY...THOUGH
WOULD NOT BE SURPRISED TO SEE CLOUDS LINGER ACROSS AT LEAST THE FAR
NORTHEAST PARTS OF THE FA THROUGH A PART OF WEDNESDAY MORNING.

RATZER

//PREV DISCUSSION...
300 PM CST

AN ACTIVE PATTERN IN THE NORTHERN STREAM WILL PROVIDE SOME UPS AND
DOWNS WITH TEMPERATURES FOR THE NEXT WEEK BUT VIRTUALLY NO CHANCE OF
ANY DROUGHT RELIEF.

TONIGHT-WEDNESDAY
MAIN CONCERNS FOR OVERNIGHT INTO WEDNESDAY ARE TEMPERATURE AND CLOUD
TRENDS. AREA OF STRATUS ACROSS MN-NORTHERN IA-WESTERN WIS. THIS
HAS BEEN ADVECTING EAST BUT LAST FEW VISIBLE SATELLITE IMAGES SHOW
SOUTHERN EDGE OF CLOUD DECK ERODING SLIGHTLY. THEREFORE THINK
STRATUS WILL STAY MAINLY N OF IL...POSSIBLY JUST CLIPPING FAR
NORTHERN COUNTIES AFTER MIDNIGHT. DESPITE WARM AIR ADVECTION
ALOFT...EXPECT ATMOSPHERE TO DECOUPLE THIS EVENING. SHOULD BE
GOOD RADIATIONAL COOLING WITH COLDEST TEMPS FAR NORTHWEST AND FAR
SOUTH WHERE SNOW COVER IS IN PLACE. STRATUS COULD HAVE SOME MINOR
IMPACT ON TEMPERATURES LATE TONIGHT NEAR THE WISCONSIN
LINE...POSSIBLY BECOMING STEADY OR RISING A BIT TOWARD DAYBREAK.
SOME SUNSHINE AND STRONG WARM AIR ADVECTION AHEAD OF APPROACHING
CLIPPER WEDNESDAY SHOULD PUSH TEMPERATURES ABOVE
GUIDANCE...ESPECIALLY IN LARGE SNOWLESS AREA FROM LASALLE COUNTY
TO CHICAGO. CONFIDENCE HIGH.

WEDNESDAY NIGHT-THURSDAY
CLIPPER MOVES FROM CENTRAL CANADA TO THE NORTHERN GREAT LAKES
WEDNESDAY NIGHT AND THURSDAY. SYSTEM MOVING INTO A VERY DRY AIR MASS
AND BEST DYNAMICS WELL NORTH OF THE LOCAL AREA...THEREFORE ONLY
EXPECT FLURRIES OR VERY LIGHT SNOW...WITH ONLY ABOUT A 20 PERCENT
CHANCE OF MEASURABLE PRECIP GENERALLY NORTH OF I-80. FLURRIES MAY
CONTINUE INTO THURSDAY IN COLD CYCLONIC FLOW. TEMPERATURES SHOULDN`T
FALL MUCH WEDNESDAY NIGHT UNDER STRONG SOUTHWEST FLOW AND INCREASING
CLOUD COVER. THEN TURNING BLUSTERY AND COLDER FOR THURSDAY.
CONFIDENCE HIGH.

FRIDAY-MONDAY
STRONG WARM AIR ADVECTION RETURNS FRIDAY AHEAD OF NEXT CLIPPER. THIS
SYSTEMS LOOKS TO BE EVEN MILDER THAN WEDNESDAY WITH 850 TEMPS OF +2
TO +4. AGAIN WILL TREND ABOVE GUIDANCE ESPECIALLY FOR AREAS WITH NO
SNOW COVER. SHOULD BE NEAR OR ABOVE FREEZING FRIDAY AND MID 30S BY
SATURDAY. ONLY SLIGHTLY COOLER SUNDAY BEHIND THE CLIPPER. AGAIN
NO PRECIP EXPECTED WITH SATURDAYS CLIPPER. MILD DRY PATTERN
CONTINUES FOR THE FIRST PART OF NEXT WEEK WITH TEMPERATURES IN THE
UPPER 30S AND POSSIBLY TAGGING 40. CONFIDENCE MEDIUM-HIGH.

ALLSOPP

&&

.AVIATION...

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

* MVFR CIGS SEEM TO BE ON THE WAY...AND IF THEY MAKE IT INTO THE
  TERMINALS...MAY END UP STICKING AROUND A WHILE.

LENNING

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

HAVE BEEN TRACKING AN AREA OF LOWER CLOUDS SINCE LAST EVENING.
THIS HAS MOVED INTO NW IL AND LIKELY WILL BE INTO RFD WITHIN AN
HOUR OR SO. WHETHER IT GETS TO ORD IS LESS CERTAIN...AND INTO MDW
EVEN MORE UNCERTAIN. ELECTED TO KEEP THE SAME TIMING AS PREVIOUS
TAFS...BUT INCREASED COVERAGE FROM SCT TO BKN AT ORD.

WINDS START VERY LIGHT FROM THE WEST OR NORTHWEST AND GRADUALLY
TURN TO THE SOUTHWEST TODAY...NEVER GETTING ESPECIALLY STRONG.

FLURRIES OR LIGHT SNOW ARE POSSIBLE WEDNESDAY NIGHT INTO THURSDAY.

LENNING


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

* ONLY MEDIUM CONFIDENCE IN CIG TRENDS...BUT HIGHER CONFIDENCE
  THEY WILL AT LEAST STAY ABOVE IFR AND RANGE FROM 1500 TO 2500 FT.

LENNING

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

* THURSDAY...OCCASIONAL FLURRIES. MVFR POSSIBLE.
* FRIDAY THROUGH MONDAY...DRY. VFR.

&&

.MARINE...
202 PM CST

I ISSUED A SMALL CRAFT ADVISORY EARLIER THIS MORNING FOR THE INDIANA
SHORES DUE TO NORTHWESTERLY WINDS OF 20 TO 25 KT AND BUILDING WAVES
UP TO 4 TO 6 FT. THE WINDS HAVE BEEN SLOWLY DIMINISHING OVER THE
PAST COUPLE OF HOURS...WITH WINDS OUT OF THE NORTHWEST IN THE 15 TO
20 KT RANGE. I WILL KEEP THIS ADVISORY GOING THROUGH MOST OF TONIGHT
AS WAVES WILL LIKELY BE SLOW TO SUBSIDE BELOW 4 FEET.

OTHERWISE...THE MAIN CONCERNS OVER THE LAKE WILL BE ON THURSDAY
THROUGH FRIDAY AS THE ANOTHER EPISODE OF HIGH WINDS IS EXPECTED. ON
THURSDAY...A POTENT AREA OF HIGH PRESSURE IS EXPECTED TO BUILD
ACROSS THE CENTRAL AND SOUTHERN PLAINS...EASTWARD ACROSS THE MIDDLE
MISSISSIPPI VALLEY. AT THE SAME TIME...AN AREA OF LOW PRESSURE WILL
TRACK EASTWARD ACROSS THE UPPER GREAT LAKES. THESE TWO PRESSURE
SYSTEMS WILL RESULT IN A DECENT PRESSURE GRADIENT ACROSS THE LAKE
LATER THURSDAY...LIKELY RESULTING IN AN UPTAKE IN THE WIND SPEEDS AS
THEY BECOME WESTERLY. AT THIS TIME IT APPEARS THE WINDS WILL BE
AROUND 30 KT. HOWEVER...I CANNOT RULE OUT A FEW GALES...SO I WILL
CONTINUE TO THE MENTION. THE WINDS DONT LOOK TO DIMINISH MUCH INTO
FRIDAY AS ANOTHER WEAK TROUGH OF LOW PRESSURE TRACKS TO THE
NORTH...ESSENTIALLY MAINTAINING THE STRENGTH OF THE GRADIENT.

FROM SATURDAY INTO NEXT WEEK IT APPEARS THE WEATHER PATTERN ACROSS
THE UPPER MIDWEST AND UPPER GREAT LAKES WILL REMAIN VERY ACTIVE. IN
FACT...IT APPEARS A PARADE OF LOW PRESSURE SYSTEMS WILL CONTINUE TO
TRACK ACROSS THE UPPER GREAT LAKES EVERY DAY OR TWO THROUGH AT LEAST
THE MIDDLE OF NEXT WEEK AS HIGH PRESSURE DOMINATES ACROSS THE
SOUTHERN CONUS. OVERALL THIS LOOKS TO RESULT IN A FAIRLY PROLONGED
PERIOD OF ELEVATED WEST TO SOUTHWESTERLY WINDS OF 25 TO 30 KT
THROUGH MUCH OF THE PERIOD. THERE COULD ALSO BE A FEW PERIODS OF
GALE FORCE WINDS DURING THE PERIOD.

KJB

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 4 AM WEDNESDAY.

&&

$$






AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

 936 PM EST THU JAN 3 2013

.SYNOPSIS...
A DISTURBANCE MOVING OFF THE GREAT LAKES MAY SPAWN SCATTERED
LIGHT SNOW SHOWERS TONIGHT. OTHERWISE...SEASONABLY COLD WEATHER
WILL CONTINUE INTO THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
CLOUDS HAVE OVERSPREAD THE REGION WITH A STRAY FLURRY REPORTED
MAINLY ACROSS THE FAR NORTH. ONLY MAJOR CHANGE WAS TO RAISE MINS
TEMPS 2 TO 3 DEGREES WITH CLOUDS AND 850MB WARM ADVECTION KEEPING
TEMPERATURES UP OVERNIGHT. DID NOT CHANGE SNOW SHOWERS CHANCES
ACROSS THE NORTH AND RIDGES FOR NOW BUT BULK OF ACTIVITY IS
OCCURRING WELL NORTH OF REGION IN THE EASTERN LEE OF LAKE ERIE.
VERY LITTLE PRECIP ELSEWHERE SO CURRENT FORECAST POPS ACROSS THE
NORTH AND RIDGES MAY BE OVERDONE WITH LITTLE UPPER LEVEL SUPPORT
FOR ASCENT WITH DEEP MOISTURE LACKING. STILL LOOKING FOR SOME LIGHT
SNOW ACROSS I-80 CORRIDOR AND THE RIDGES AND A FEW FLURRIES
ELSEWHERE. ACCUMULATIONS ACROSS THE NORTH AND RIDGES WILL BE WELL
UNDER AN INCH AND LIKELY JUST A DUSTING.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
A GENERALLY DRY AND BELOW NORMAL PERIOD WILL PERSIST ACROSS THE
AREA HEADING INTO THE WEEKEND. DECENT MODEL AGREEMENT EXISTS ON AT
LEAST SOME CLEARING WITH LITTLE CHANCE OF PRECIPITATION UNTIL
ROUGHLY SATURDAY NIGHT/SUNDAY. AT THAT TIME...THE MODELS TRACK A
DUET OF WAVES NEAR THE AREA...FIRST FROM THE SOUTHERN
STREAM...THEN A MORE CLIPPERESQUE TYPE MID-LEVEL SYSTEM THAT DROPS
SOUTHEASTWARD FROM THE CANADIAN PRAIRIE PROVINCES. DUE TO THEIR
CONTINENTAL ORIGINS...NEITHER OF THESE LOOK TO BE PARTICULARLY
MOISTURE-LADEN...SO POPS WERE KEPT TO THE CHANCE CATEGORY FOR THE
MOMENT. HOWEVER THROUGHOUT THE PERIOD...THERMAL PROFILES FROM THE
CONSENSUS FAVOR DEEP ENOUGH COLD AIR TO SUPPORT SNOW THROUGHOUT
THEIR PASSAGE.

WHILE TEMPERATURES REMAIN BELOW NORMAL...THEY DO MODERATE FAIRLY
SIGNIFICANTLY TOWARD THE MID 30S BY THE END OF THE WEEKEND. THIS
WILL BE A BRIEF SEGUE TO MUCH MORE ABRUPT WARMING BY NEXT WEEK.
FRIES

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
BLEND OF RECENT MEDIUM RANGE MODELS SHOW LINGERING POST SYSTEM
CLOUDS ACROSS THE UPPER OHIO VALLEY INTO MONDAY. ENSUING HIGH
PRESSURE WILL PROMOTE A DRY PERIOD INTO MID WEEK.

JUDGING FROM RECENT GFS AND ECMWF MOS...EXPECT TEMPERATURES TO BE
NEAR SEASONABLE LEVELS.

&&

.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
RECENT RAP AND SREF MODEL OUTPUT SHOW INCOMING COLD FRONT
WEAKENING DURING ITS EASTBOUND PASSAGE TONIGHT. SO EXPECT MAINLY
MVFR STRATOCUMULUS CEILINGS TONIGHT AND FRIDAY MORNING. ANY
ASSOCIATED SNOW SHOWERS WILL BE LIGHT AND SCATTERED...AND MAINLY
CONFINED TO MAINLY THE I-80 CORRIDOR AND APPALACHIAN MOUNTAINS. SO
NO ADDITIONAL RESTRICTIONS WERE FORECASTED.

ENSUING HIGH PRESSURE WILL PROMOTE VFR FRIDAY AFTERNOON AND NIGHT.

NAM MODEL PROFILES SHOW VERTICAL MIXING WILL CAUSE SURFACE
WINDS...FROM THE SOUTHWEST THIS AFTERNOON...TO INCREASE TO 10 KTS
WITH GUSTS TO ABOUT 20 KTS. WINDS CAN BE A TAD MORE WESTERLY TONIGHT
AND LESS GUSTY. WINDS FRIDAY CAN AGAIN BE SOUTHWEST AT 10 KTS WITH
GUSTS TO 20 KTS.

.OUTLOOK.../SATURDAY THROUGH MONDAY/...
VFR UNTIL POSSIBLE RESTRICTIONS SATURDAY NIGHT AND SUNDAY AS A
WEAK COLD FRONT MOVES ACROSS THE GREAT LAKES.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$









AREA FORECAST DISCUSSION

NWS GAYLORD MI

 103 PM EST WED JAN 2 2013

.SYNOPSIS...
ISSUED AT 449 AM EST WED JAN 2 2013

OCCASIONAL LAKE EFFECT SNOW SHOWERS WILL CONTINUE FOR MOST OF THIS
WEEK...WITH A MORE ROBUST PERIOD OF LAKE ENHANCED SNOW THURSDAY...AS
THE NEXT CLIPPER SYSTEM MOVES THROUGH THE AREA. WARMER AND DRIER AIR
THEN BEGIN TO MOVE INTO THE REGION FRIDAY AND OVER THE WEEKEND FOR
SIGNIFICANTLY LOWER SNOW CHANCES.

&&

.UPDATE...
ISSUED AT 1256 PM EST WED JAN 2 2013

LES LIGHT SNOW AND FLURRIES CONTINUES ACROSS THE REGION. ADDED A
LITTLE TO ACCUMULATIONS NEAR THE TIP OF THE MIT WHERE VSBYS HAVE
BEEN DOWN TO 1 1/2 AT TIMES...BUT STILL ONLY HAVE 1 TO 2 INCHES
TOTAL DAYTIME ACCUMULATIONS. OTHERWISE...JUST SOME MINOR TWEAKS
FOR TIMING/COVERAGE.

UPDATE ISSUED AT 1008 AM EST WED JAN 2 2013

NO BIG CHANGES TO THE FORECAST. EXTENDED LAKE EFFECT FLURRIES INTO
EARLY AFTERNOON ACROSS EASTERN COUNTIES AS THE FLOW REMAINS
WESTERLY (BEFORE BACKING INTO THE SOUTHWEST LATER ON).
OTHERWISE...LOWERED MAXES BY A DEGREE OR TWO MOST SPOTS (EXCEPT
FOR NEAR THE LAKE MICHIGAN SHORELINE WHERE HAD TO ADD A DEGREE OR
SO).

UPDATE ISSUED AT 638 AM EST WED JAN 2 2013

FORECAST GOING ALONG TO PLAN THIS MORNING WITH FLURRIES IN THE
WESTERLY FLOW REGIMES...EXPANDED FROM INVADING WIDESPREAD LOW
LEVEL STRATUS. THIS STRATUS HAS COVERED ALMOST EVERYONE (ALPENA
WITHIN THE NEXT HOUR OR SO). THERE IS A LOSS OF CONFIDENCE IN THE
DEVELOPMENT OF A PRETTY GOOD BAND OF SNOW OUT OVER LAKE HURON. THE
DRAINAGE FLOW INTO THIS AREA...IS LAGGING BY A FEW HOURS. SO
REMOVED THE HIGH CHANCES FOR SNOW...AND CERTAINLY FOR THE NE LOWER
COAST. WILL HOLD ON TO SOME HOPE BY EARLY AFTERNOON...BUT NOT SO
SURE ABOUT THAT EITHER. ALL OF NRN LOWER SHOULD MAINLY SEE
FLURRIES...UNTIL LATER THIS AFTERNOON...WHEN INCREASING MOISTURE
AND A SW FLOW MAY BRING A FEW TENTHS TO THE NW LOWER COAST.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 449 AM EST WED JAN 2 2013

WEAK HIGH PRESSURE WAS SETTLED IN OVER THE REGION...WITH MUCH
COLDER AIR ACROSS ONTARIO DRAINING IN ACROSS EASTERN LAKE
SUPERIOR...ENHANCING A LOW LEVEL COLD FRONT/CONVERGENCE. THIS
CONVERGENCE AND AIR FLOW OVER LAKE SUPERIOR PRODUCED QUITE THE
MODERATE/INTENSE SNOW BAND THAT FILTERED IN MAINLY JUST THE
PARADISE AREA A FEW HOURS BACK. THIS BAND OF SNOW HAS WEAKENED
OVER EASTERN UPPER DUE TO LOSS OF A DECENT FETCH. THE REST OF NRN
MICHIGAN WAS SEEING A RAPIDLY APPROACHING STRATUS LAYER FROM LAKE
MICHIGAN AND WISCONSIN...WITH A CONTINUED EXPECTATION TO SWEEP
OVER ALL OF THE REGION. CLEAR SKIES IN SPOTS ACROSS FAR NRN LOWER
AND NE LOWER WILL BECOME CLOUDY AGAIN. FLURRIES WERE STILL FAIRLY
PREVALENT OUTSIDE OF THE CLEAR REGIONS...AND THE UPSTREAM CLOUDS
ALSO CONTAIN FLURRIES. RADAR SHOWING THIS IS THE CASE...WITH NEW
ECHOES POPPING UP OVER LAKE MICHIGAN. TEMPERATURES WERE IN THE
TEENS AND LOWER 20S.

NEXT ALBERTA CLIPPER WAS MOVING INTO FAR NRN MN WITH TROUGHING
EXTENDING EASTWARD AND CONNECTING WITH THE ENHANCED TROUGHING FROM
THE COLD AIR DRAINAGE/COLD FRONT. THE SYSTEM COLD FRONT WAS DRAPED
THROUGH EASTERN ND/SD AND DOWN INTO NEBRASKA. DEEPER MOISTURE WAS
SEEN VIA SATELLITE ALONG AND BEHIND THE COLD FRONT...AS WELL
AROUND THE NRN PERIPHERY OF THE LOW PRESSURE.

TODAY AND TONIGHT...WILL BE RAMPING FOR THE ARRIVAL OF THE CLIPPER
LATE TONIGHT AND INTO THURSDAY. THE STRATUS FROM WISCONSIN WAS
ERODING FROM THE SW...WITHIN WEAK WARM AIR ADVECTION INTO THE
CLOUD LAYER. NOT WORRIED TOO MUCH ABOUT THIS WARM ADVECTION
ERODING THE STRATUS FOR US...SINCE LOW LEVEL TEMPS OF -8C TO -10C
HOLD THROUGHOUT THE DAY...SUFFICIENT COLD ENOUGH TO KEEP NOT ONLY
CLOUDS IN PLACE...BUT TO ALSO ALLOW FOR THE CONTINUED GENERATION
OF LAKE EFFECT FLURRIES. THESE FLURRIES WILL BE WITHIN WEST FLOW
REGIMES THIS MORNING...THEN SW FLOW REGIMES AS WINDS BACK AHEAD OF
THE APPROACHING LOW PRESSURE. ONE FLY IN THE OINTMENT THAT COULD
HAVE SOME SIGNIFICANT RAMIFICATIONS IN THE SNOWFALL/AMOUNTS IS FOR
THE DRAINAGE FLOW FROM ONTARIO...EXPECTED TO ENHANCE CONVERGENCE
OVER LAKE HURON...WHICH COULD NEAR THE NE LOWER SHORELINE. HI RES
MODELS/LATEST RUC ARE STEADFAST ON THIS IDEA BY DAYBREAK...WITH
THE DEVELOPMENT OF ANOTHER MODERATE/INTENSE LAKE SNOW BAND.
CONFIDENCE IN THIS ISN`T THE GREATEST...DUE IN PART TO THE
DRAINAGE LAGGING THE HI RES TIMING (NOT EVEN INTO THE SAULT RIGHT
NOW)...AND THAT MIXING INTO THE MORNING MIGHT KEEP THE CONVERGENCE
WELL OUT INTO NRN LAKE HURON...NOT THREATENING OUR COASTAL AREAS.
THIS IS SOMETHING TO KEEP A CLOSE EYE ON...AS THE ARRIVAL OF THE
CONVERGENCE INTO FAR NRN LOWER AND EASTERN UPPER...WOULD ENHANCE
CONVERGENCE AND RESULT IN STRONGER THAN EXPECTED SNOWS.
AGAIN...NOT ENTIRELY SOLD ON THIS. DID INCREASE CHANCES FOR SEEING
BONA FIDE SNOWS AND SMALL ACCUMULATIONS...BUT FEELING IS FOR ANY
ACCUMS TO REMAIN UNDER AN INCH.

WE WILL HAVE TO WAIT FOR INCREASED SW WINDS AND DEEPER MOISTURE
AHEAD OF THE CLIPPER`S COLD FRONT. THIS HAPPENS THROUGH THE
NIGHT...BUT MAINLY AFTER MIDNIGHT. INCREASED MOISTURE FLUX OFF
THE LAKES WILL HELP...BUT INVERSION HEIGHTS RISING TO MAYBE
4500-5000FEET WITH DELTA T`S UNDER 15C...AND NO GOOD SUPPORT ALOFT
WILL MORE LIKELY RESULT IN ACCUMULATIONS IN THE 1-2 INCH RANGE
WITH A SLIVER OF AN AREA ACROSS CENTRAL CHIP/MACK COUNTIES...AND
EMMET COUNTY SEEING UP TO 3 INCHES. IF THERE IS A LAKE HURON BAND
OF SNOW THAT DEVELOP THIS MORNING...THE SW FLOW WILL GRADUALLY
PUSH THIS SNOW IN ACROSS DRUMMOND ISLAND BEFORE DEPARTING EAST OF
THERE. VERY DIFFICULT MESOSCALE FORECAST IN THE SHORT TERM.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 449 AM EST WED JAN 2 2013

ENERGETIC SPLIT FLOW PATTERN SET TO CONTINUE...WITH ONE LAST
NORTHERN STREAM ORIGINATED SHORTWAVE SET TO VISIT OUR AREA LATER
TONIGHT INTO THURSDAY. AFTERWARD...NORTHERN STREAM PROGGED TO
RETREAT NORTH...BOTTLING UP THE ARCTIC COLD WELL TO OUR NORTH FOR
THE FORESEEABLE FUTURE...PART OF A BURGEONING POSITIVE AO SIGNATURE
AND EAST DISPLACED NORTH ATLANTIC BLOCKING. NOT TO SAY THE PATTERN
DOESN`T HOLD AT LEAST SOME SNOW POTENTIAL FOR THE SNOW ENTHUSIASTS
AMONGST US...WITH THURSDAY`S LEAD CHARGING SYSTEM HAVING THE LOOKS
OF A RATHER SNEAKY LAKE ENHANCED SNOW EVENT FOR THE TRADITIONAL
SNOWBELTS. TAKING A LOOK EVEN FURTHER OUT...MAY SEE THE BEGINNINGS
OF THE INFAMOUS "JANUARY THAW" HEADING INTO NEXT WORK WEEK...WITH
WELL AGREED UPON PROGS SUGGESTING A FURTHER RELAXATION OF THE
NORTHERN STREAM AND A FLOODING OF MODIFIED PACIFIC AIR ACROSS THE
CONUS. LARGE SCALE INDICES WOULD TEND TO AGREE...ALTHOUGH WITH
DOMINATE POLAR VORTEX ON THIS SIDE OF THE GLOBE...HAVE SOME
SUSPICION NORTHERN STREAM WILL NOT YIELD AS AGGRESSIVELY AS SOME
PROGS WOULD SUGGEST. GETTING A TOUCH AHEAD OF MYSELF...AND STILL
HAVE AMPLE CONCERNS IN THE SHORT TERM PORTION OF THE LONG TERM TO
DEAL WITH...MOST NOTABLY THURSDAY`S SNOW POTENTIAL.

DEFINITELY AN INTRIGUING SYSTEM FOR THURSDAY AS FAST MOVING AREA OF
LOW PRESSURE SLICES ACROSS LAKE SUPERIOR EARLY...DRAGGING AN EQUALLY
FAST MOVING COLD FRONT THROUGH NORTHERN MICHIGAN DURING THE MORNING.
WHILE CORE OF BETTER MID LEVEL DYNAMICS LOOK TO PASS BY JUST TO OUR
NORTH..STILL DECENT SLUG OF UPWARD QG SUPPORT ALONG SHARP SHORTWAVE
TROUGH AXIS PASSING OVERHEAD. DEEP LAYER MOISTURE NOTHING TO WRITE
HOME ABOUT...WITH PWAT VALUES STRUGGLING TO EXCEED A QUARTER OF AN
INCH. STILL...WOULD EXPECT AT LEAST SOME SYNOPTIC DRIVEN SNOWS TO
ACCOMPANY SHORTWAVE PASSAGE DURING THE MORNING. WILD CARD REMAINS
LAKE ENHANCEMENT POTENTIAL...BOTH ALONG AND PROCEEDING COLD FRONTAL
PASSAGE. PREFRONTAL AIRMASS MORE THAN COLD ENOUGH TO SUPPORT LAKE
ENHANCED SNOWS...PARTICULARLY AS CONVERGENCE IS MAXIMIZED ALONG
FRONTAL SLOPE. TEMPERATURES COOL FURTHER IMMEDIATELY BEHIND THE
FRONT...WITH H85 READINGS APPROACHING THE NEGATIVE MIDDLE TEENS BY
AFTERNOON. MOISTURE REMAINS ABUNDANT UNTIL MID LEVEL TROUGH PASSAGE
DURING THE AFTERNOON...SUGGESTING AT LEAST A SEVERAL HOUR WINDOW OF
GOOD LAKE ENHANCED SNOWS IN FAVORED WNW-NW FLOW AREAS THROUGH THE
MORNING. MODEL DERIVED SOUNDING BEAR THIS POTENTIAL OUT (ESPECIALLY
NAM-BUFR SOUNDINGS WHICH HAVE SOME SUPPORT FROM LATEST ECMWF
PROGS)...WITH QUICK UPTICK TO NEAR H75 INVERSION LEVELS...ALL THE
WHILE OMEGA MAX BECOMES CENTERED IN PRIME DGZ. HOW WILL ALL THIS
PLAY OUT? KINDA ENVISION A PERIOD OF DECENT SNOWS ACROSS NORTHWEST
LOWER/EASTERN UPPER MICHIGAN WITH THE FRONTAL PASSAGE...WITH A QUICK
TRANSITION TO WNW-NW LAKE ENHANCED SNOWS THROUGH THE REMAINDER OF
THE MORNING. ACTIVITY SHOULD BEGIN TO WIND DOWN RATHER QUICKLY
DURING THE AFTERNOON...AND ESPECIALLY THURSDAY EVENING...AS MOISTURE
RAPIDLY DEPARTS. CIPS ANALOGS FOR THIS EVENT HONING IN ON SOME
INTERESTING NUMBERS...WITH IMPACT GUIDANCE SHOWING 6 TO 8 INCH
AMOUNTS IN THE TRADITIONAL SNOWBELTS OF BOTH PENINSULAS. QUICK
MOVEMENT OF SYSTEM AND SOME LINGERING CONCERN WITH EXACT THERMAL
STRUCTURES (SOME GUIDANCE NOT QUITE AS COLD) PREVENTS FROM GOING
THIS AGGRESSIVE...BUT WILL GO AHEAD A RAISE INHERITED SNOW AMOUNTS
BY AT LEAST AN INCH OR SO...BRINGING DAYTIME ACCUMULATIONS TO 2 TO 3
INCHES IN FAVORED AREAS. IF TRENDS HOLD...MAY EVENTUALLY NEED AN
ADVISORY FOR AT LEAST SOME COUNTIES OF NORTHWEST LOWER AND EASTERN
UPPER MICHIGAN. SYSTEM EXITS JUST AS QUICK AS IT ARRIVES...WITH ANY
LINGERING SNOW SHOWERS COMING TO AN END OVERNIGHT THURSDAY AS MOISTURE
DEPARTS AND WAA COMMENCES.

CONDITIONS LOOK QUIET AND A TOUCH WARMER TO END THE WORK WEEK AS THE
NORTHERN STREAM RELAXATION BEGINS...LETTING HEIGHTS BUILD AND
SOUTHWEST WINDS TO DEVELOP ON NORTH SIDE OF SOUTHERN HIGH PRESSURE.
NEXT MOISTURE STARVED SYSTEM ARRIVES OVER THE WEEKEND...PERHAPS
BRINGING A FEW SNOW SHOWERS ONCE AGAIN SATURDAY INTO SATURDAY NIGHT.
TEMPERATURES APPEAR TOO MARGINAL FOR ANY PRE AND POST FRONTAL LAKE
ENHANCEMENT. MAIN STORM TRACK CONTINUES TO TREND FURTHER NORTH
HEADING INTO NEXT WORK WEEK. PACIFIC AIR STILL APPEARS RATHER
AGGRESSIVE...WITH LATEST PROGS SUGGESTING MUCH OF THE NORTHERN CONUS
FLOODED BY ABOVE NORMAL TEMPERATURES BY THE MIDDLE OF NEXT WEEK.
FORECAST WILL REFLECT THE BEGINNING OF THIS WARM-UP...WITH READINGS
RUNNING SEVERAL DEGREES ABOVE NORMAL BY MONDAY AND TUESDAY. AS
MENTIONED EARLIER...NOT ENTIRELY SOLD YET ON THIS AGGRESSIVE
WARMING...AND STILL PLAUSIBLE FOR BRIEF NORTHERN STREAM FORAYS TO
KEEP THE BULK OF THE WARMING OFF TO OUR WEST.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1256 PM EST WED JAN 2 2013

MVFR CIGS FOR THE MOST PART THROUGH THE TAF PERIOD. THE EXCEPTION
IS LOW END VFR CIGS AT APN THROUGH THIS EVENING. LAKE EFFECT SNOW
SHOWERS AND FLURRIES TO CONTINUE THROUGH THIS EVENING AND LIKELY
BECOME ENHANCED AT PLN AND MBL LATE TONIGHT INTO THURSDAY MORNING
AS AN ALBERTA CLIPPER MOVES BY TO OUR NORTH.

&&

.MARINE...
ISSUED AT 449 AM EST WED JAN 2 2013

WINDS WILL GRADUALLY WEAKEN TODAY...BEFORE PICKING BACK UP AGAIN
TONIGHT...IN ADVANCE OF AN ALBERTA CLIPPER AND ASSOCIATED COLD
FRONT. THE TIGHTEST GRADIENT WILL RESIDE ACROSS THE NW LOWER
NEARSHORE...THROUGH THE STRAITS AND INTO NRN LAKE HURON. OVERLAKE
INSTABILITY WILL BE DEEPENING WITH THE ABILITY TO TAP ADVISORY
LEVEL GUSTS IN THESE AREAS. IN ADDITION...THIS DEEPENING
INSTABILITY...AND DEEPER MOISTURE FROM THE CLIPPER...WILL RESULT
IN ENHANCED LAKE EFFECT SNOW SHOWERS. THE WINDS WILL BE STRONGEST
BEHIND THE COLD FRONT...THURSDAY THROUGH FRIDAY...AND THESE
ADVISORIES WILL NOT ONLY NEED TO BE EXTENDED...BUT THE REMAINDER
OF THE NEARSHORE WATERS WILL LIKELY NEED ADVISORIES TOO.


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 1 AM EST FRIDAY FOR LHZ345>349.
LM...SMALL CRAFT ADVISORY UNTIL 1 AM EST FRIDAY FOR LMZ323-342-
     344>346.
LS...NONE.

&&

$$

UPDATE...AS
SYNOPSIS...MB
SHORT TERM...SD
LONG TERM...MB
AVIATION...AS
MARINE...SD







AREA FORECAST DISCUSSION

NWS GAYLORD MI

 1013 AM EST WED JAN 2 2013

.SYNOPSIS...
ISSUED AT 449 AM EST WED JAN 2 2013

OCCASIONAL LAKE EFFECT SNOW SHOWERS WILL CONTINUE FOR MOST OF THIS
WEEK...WITH A MORE ROBUST PERIOD OF LAKE ENHANCED SNOW THURSDAY...AS
THE NEXT CLIPPER SYSTEM MOVES THROUGH THE AREA. WARMER AND DRIER AIR
THEN BEGIN TO MOVE INTO THE REGION FRIDAY AND OVER THE WEEKEND FOR
SIGNIFICANTLY LOWER SNOW CHANCES.

&&

.UPDATE...
ISSUED AT 1008 AM EST WED JAN 2 2013

NO BIG CHANGES TO THE FORECAST. EXTENDED LAKE EFFECT FLURRIES INTO
EARLY AFTERNOON ACROSS EASTERN COUNTIES AS THE FLOW REMAINS
WESTERLY (BEFORE BACKING INTO THE SOUTHWEST LATER ON).
OTHERWISE...LOWERED MAXES BY A DEGREE OR TWO MOST SPOTS (EXCEPT
FOR NEAR THE LAKE MICHIGAN SHORELINE WHERE HAD TO ADD A DEGREE OR
SO).

UPDATE ISSUED AT 638 AM EST WED JAN 2 2013

FORECAST GOING ALONG TO PLAN THIS MORNING WITH FLURRIES IN THE
WESTERLY FLOW REGIMES...EXPANDED FROM INVADING WIDESPREAD LOW
LEVEL STRATUS. THIS STRATUS HAS COVERED ALMOST EVERYONE (ALPENA
WITHIN THE NEXT HOUR OR SO). THERE IS A LOSS OF CONFIDENCE IN THE
DEVELOPMENT OF A PRETTY GOOD BAND OF SNOW OUT OVER LAKE HURON. THE
DRAINAGE FLOW INTO THIS AREA...IS LAGGING BY A FEW HOURS. SO
REMOVED THE HIGH CHANCES FOR SNOW...AND CERTAINLY FOR THE NE LOWER
COAST. WILL HOLD ON TO SOME HOPE BY EARLY AFTERNOON...BUT NOT SO
SURE ABOUT THAT EITHER. ALL OF NRN LOWER SHOULD MAINLY SEE
FLURRIES...UNTIL LATER THIS AFTERNOON...WHEN INCREASING MOISTURE
AND A SW FLOW MAY BRING A FEW TENTHS TO THE NW LOWER COAST.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 449 AM EST WED JAN 2 2013

WEAK HIGH PRESSURE WAS SETTLED IN OVER THE REGION...WITH MUCH
COLDER AIR ACROSS ONTARIO DRAINING IN ACROSS EASTERN LAKE
SUPERIOR...ENHANCING A LOW LEVEL COLD FRONT/CONVERGENCE. THIS
CONVERGENCE AND AIR FLOW OVER LAKE SUPERIOR PRODUCED QUITE THE
MODERATE/INTENSE SNOW BAND THAT FILTERED IN MAINLY JUST THE
PARADISE AREA A FEW HOURS BACK. THIS BAND OF SNOW HAS WEAKENED
OVER EASTERN UPPER DUE TO LOSS OF A DECENT FETCH. THE REST OF NRN
MICHIGAN WAS SEEING A RAPIDLY APPROACHING STRATUS LAYER FROM LAKE
MICHIGAN AND WISCONSIN...WITH A CONTINUED EXPECTATION TO SWEEP
OVER ALL OF THE REGION. CLEAR SKIES IN SPOTS ACROSS FAR NRN LOWER
AND NE LOWER WILL BECOME CLOUDY AGAIN. FLURRIES WERE STILL FAIRLY
PREVALENT OUTSIDE OF THE CLEAR REGIONS...AND THE UPSTREAM CLOUDS
ALSO CONTAIN FLURRIES. RADAR SHOWING THIS IS THE CASE...WITH NEW
ECHOES POPPING UP OVER LAKE MICHIGAN. TEMPERATURES WERE IN THE
TEENS AND LOWER 20S.

NEXT ALBERTA CLIPPER WAS MOVING INTO FAR NRN MN WITH TROUGHING
EXTENDING EASTWARD AND CONNECTING WITH THE ENHANCED TROUGHING FROM
THE COLD AIR DRAINAGE/COLD FRONT. THE SYSTEM COLD FRONT WAS DRAPED
THROUGH EASTERN ND/SD AND DOWN INTO NEBRASKA. DEEPER MOISTURE WAS
SEEN VIA SATELLITE ALONG AND BEHIND THE COLD FRONT...AS WELL
AROUND THE NRN PERIPHERY OF THE LOW PRESSURE.

TODAY AND TONIGHT...WILL BE RAMPING FOR THE ARRIVAL OF THE CLIPPER
LATE TONIGHT AND INTO THURSDAY. THE STRATUS FROM WISCONSIN WAS
ERODING FROM THE SW...WITHIN WEAK WARM AIR ADVECTION INTO THE
CLOUD LAYER. NOT WORRIED TOO MUCH ABOUT THIS WARM ADVECTION
ERODING THE STRATUS FOR US...SINCE LOW LEVEL TEMPS OF -8C TO -10C
HOLD THROUGHOUT THE DAY...SUFFICIENT COLD ENOUGH TO KEEP NOT ONLY
CLOUDS IN PLACE...BUT TO ALSO ALLOW FOR THE CONTINUED GENERATION
OF LAKE EFFECT FLURRIES. THESE FLURRIES WILL BE WITHIN WEST FLOW
REGIMES THIS MORNING...THEN SW FLOW REGIMES AS WINDS BACK AHEAD OF
THE APPROACHING LOW PRESSURE. ONE FLY IN THE OINTMENT THAT COULD
HAVE SOME SIGNIFICANT RAMIFICATIONS IN THE SNOWFALL/AMOUNTS IS FOR
THE DRAINAGE FLOW FROM ONTARIO...EXPECTED TO ENHANCE CONVERGENCE
OVER LAKE HURON...WHICH COULD NEAR THE NE LOWER SHORELINE. HI RES
MODELS/LATEST RUC ARE STEADFAST ON THIS IDEA BY DAYBREAK...WITH
THE DEVELOPMENT OF ANOTHER MODERATE/INTENSE LAKE SNOW BAND.
CONFIDENCE IN THIS ISN`T THE GREATEST...DUE IN PART TO THE
DRAINAGE LAGGING THE HI RES TIMING (NOT EVEN INTO THE SAULT RIGHT
NOW)...AND THAT MIXING INTO THE MORNING MIGHT KEEP THE CONVERGENCE
WELL OUT INTO NRN LAKE HURON...NOT THREATENING OUR COASTAL AREAS.
THIS IS SOMETHING TO KEEP A CLOSE EYE ON...AS THE ARRIVAL OF THE
CONVERGENCE INTO FAR NRN LOWER AND EASTERN UPPER...WOULD ENHANCE
CONVERGENCE AND RESULT IN STRONGER THAN EXPECTED SNOWS.
AGAIN...NOT ENTIRELY SOLD ON THIS. DID INCREASE CHANCES FOR SEEING
BONA FIDE SNOWS AND SMALL ACCUMULATIONS...BUT FEELING IS FOR ANY
ACCUMS TO REMAIN UNDER AN INCH.

WE WILL HAVE TO WAIT FOR INCREASED SW WINDS AND DEEPER MOISTURE
AHEAD OF THE CLIPPER`S COLD FRONT. THIS HAPPENS THROUGH THE
NIGHT...BUT MAINLY AFTER MIDNIGHT. INCREASED MOISTURE FLUX OFF
THE LAKES WILL HELP...BUT INVERSION HEIGHTS RISING TO MAYBE
4500-5000FEET WITH DELTA T`S UNDER 15C...AND NO GOOD SUPPORT ALOFT
WILL MORE LIKELY RESULT IN ACCUMULATIONS IN THE 1-2 INCH RANGE
WITH A SLIVER OF AN AREA ACROSS CENTRAL CHIP/MACK COUNTIES...AND
EMMET COUNTY SEEING UP TO 3 INCHES. IF THERE IS A LAKE HURON BAND
OF SNOW THAT DEVELOP THIS MORNING...THE SW FLOW WILL GRADUALLY
PUSH THIS SNOW IN ACROSS DRUMMOND ISLAND BEFORE DEPARTING EAST OF
THERE. VERY DIFFICULT MESOSCALE FORECAST IN THE SHORT TERM.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 449 AM EST WED JAN 2 2013

ENERGETIC SPLIT FLOW PATTERN SET TO CONTINUE...WITH ONE LAST
NORTHERN STREAM ORIGINATED SHORTWAVE SET TO VISIT OUR AREA LATER
TONIGHT INTO THURSDAY. AFTERWARD...NORTHERN STREAM PROGGED TO
RETREAT NORTH...BOTTLING UP THE ARCTIC COLD WELL TO OUR NORTH FOR
THE FORESEEABLE FUTURE...PART OF A BURGEONING POSITIVE AO SIGNATURE
AND EAST DISPLACED NORTH ATLANTIC BLOCKING. NOT TO SAY THE PATTERN
DOESN`T HOLD AT LEAST SOME SNOW POTENTIAL FOR THE SNOW ENTHUSIASTS
AMONGST US...WITH THURSDAY`S LEAD CHARGING SYSTEM HAVING THE LOOKS
OF A RATHER SNEAKY LAKE ENHANCED SNOW EVENT FOR THE TRADITIONAL
SNOWBELTS. TAKING A LOOK EVEN FURTHER OUT...MAY SEE THE BEGINNINGS
OF THE INFAMOUS "JANUARY THAW" HEADING INTO NEXT WORK WEEK...WITH
WELL AGREED UPON PROGS SUGGESTING A FURTHER RELAXATION OF THE
NORTHERN STREAM AND A FLOODING OF MODIFIED PACIFIC AIR ACROSS THE
CONUS. LARGE SCALE INDICES WOULD TEND TO AGREE...ALTHOUGH WITH
DOMINATE POLAR VORTEX ON THIS SIDE OF THE GLOBE...HAVE SOME
SUSPICION NORTHERN STREAM WILL NOT YIELD AS AGGRESSIVELY AS SOME
PROGS WOULD SUGGEST. GETTING A TOUCH AHEAD OF MYSELF...AND STILL
HAVE AMPLE CONCERNS IN THE SHORT TERM PORTION OF THE LONG TERM TO
DEAL WITH...MOST NOTABLY THURSDAY`S SNOW POTENTIAL.

DEFINITELY AN INTRIGUING SYSTEM FOR THURSDAY AS FAST MOVING AREA OF
LOW PRESSURE SLICES ACROSS LAKE SUPERIOR EARLY...DRAGGING AN EQUALLY
FAST MOVING COLD FRONT THROUGH NORTHERN MICHIGAN DURING THE MORNING.
WHILE CORE OF BETTER MID LEVEL DYNAMICS LOOK TO PASS BY JUST TO OUR
NORTH..STILL DECENT SLUG OF UPWARD QG SUPPORT ALONG SHARP SHORTWAVE
TROUGH AXIS PASSING OVERHEAD. DEEP LAYER MOISTURE NOTHING TO WRITE
HOME ABOUT...WITH PWAT VALUES STRUGGLING TO EXCEED A QUARTER OF AN
INCH. STILL...WOULD EXPECT AT LEAST SOME SYNOPTIC DRIVEN SNOWS TO
ACCOMPANY SHORTWAVE PASSAGE DURING THE MORNING. WILD CARD REMAINS
LAKE ENHANCEMENT POTENTIAL...BOTH ALONG AND PROCEEDING COLD FRONTAL
PASSAGE. PREFRONTAL AIRMASS MORE THAN COLD ENOUGH TO SUPPORT LAKE
ENHANCED SNOWS...PARTICULARLY AS CONVERGENCE IS MAXIMIZED ALONG
FRONTAL SLOPE. TEMPERATURES COOL FURTHER IMMEDIATELY BEHIND THE
FRONT...WITH H85 READINGS APPROACHING THE NEGATIVE MIDDLE TEENS BY
AFTERNOON. MOISTURE REMAINS ABUNDANT UNTIL MID LEVEL TROUGH PASSAGE
DURING THE AFTERNOON...SUGGESTING AT LEAST A SEVERAL HOUR WINDOW OF
GOOD LAKE ENHANCED SNOWS IN FAVORED WNW-NW FLOW AREAS THROUGH THE
MORNING. MODEL DERIVED SOUNDING BEAR THIS POTENTIAL OUT (ESPECIALLY
NAM-BUFR SOUNDINGS WHICH HAVE SOME SUPPORT FROM LATEST ECMWF
PROGS)...WITH QUICK UPTICK TO NEAR H75 INVERSION LEVELS...ALL THE
WHILE OMEGA MAX BECOMES CENTERED IN PRIME DGZ. HOW WILL ALL THIS
PLAY OUT? KINDA ENVISION A PERIOD OF DECENT SNOWS ACROSS NORTHWEST
LOWER/EASTERN UPPER MICHIGAN WITH THE FRONTAL PASSAGE...WITH A QUICK
TRANSITION TO WNW-NW LAKE ENHANCED SNOWS THROUGH THE REMAINDER OF
THE MORNING. ACTIVITY SHOULD BEGIN TO WIND DOWN RATHER QUICKLY
DURING THE AFTERNOON...AND ESPECIALLY THURSDAY EVENING...AS MOISTURE
RAPIDLY DEPARTS. CIPS ANALOGS FOR THIS EVENT HONING IN ON SOME
INTERESTING NUMBERS...WITH IMPACT GUIDANCE SHOWING 6 TO 8 INCH
AMOUNTS IN THE TRADITIONAL SNOWBELTS OF BOTH PENINSULAS. QUICK
MOVEMENT OF SYSTEM AND SOME LINGERING CONCERN WITH EXACT THERMAL
STRUCTURES (SOME GUIDANCE NOT QUITE AS COLD) PREVENTS FROM GOING
THIS AGGRESSIVE...BUT WILL GO AHEAD A RAISE INHERITED SNOW AMOUNTS
BY AT LEAST AN INCH OR SO...BRINGING DAYTIME ACCUMULATIONS TO 2 TO 3
INCHES IN FAVORED AREAS. IF TRENDS HOLD...MAY EVENTUALLY NEED AN
ADVISORY FOR AT LEAST SOME COUNTIES OF NORTHWEST LOWER AND EASTERN
UPPER MICHIGAN. SYSTEM EXITS JUST AS QUICK AS IT ARRIVES...WITH ANY
LINGERING SNOW SHOWERS COMING TO AN END OVERNIGHT THURSDAY AS MOISTURE
DEPARTS AND WAA COMMENCES.

CONDITIONS LOOK QUIET AND A TOUCH WARMER TO END THE WORK WEEK AS THE
NORTHERN STREAM RELAXATION BEGINS...LETTING HEIGHTS BUILD AND
SOUTHWEST WINDS TO DEVELOP ON NORTH SIDE OF SOUTHERN HIGH PRESSURE.
NEXT MOISTURE STARVED SYSTEM ARRIVES OVER THE WEEKEND...PERHAPS
BRINGING A FEW SNOW SHOWERS ONCE AGAIN SATURDAY INTO SATURDAY NIGHT.
TEMPERATURES APPEAR TOO MARGINAL FOR ANY PRE AND POST FRONTAL LAKE
ENHANCEMENT. MAIN STORM TRACK CONTINUES TO TREND FURTHER NORTH
HEADING INTO NEXT WORK WEEK. PACIFIC AIR STILL APPEARS RATHER
AGGRESSIVE...WITH LATEST PROGS SUGGESTING MUCH OF THE NORTHERN CONUS
FLOODED BY ABOVE NORMAL TEMPERATURES BY THE MIDDLE OF NEXT WEEK.
FORECAST WILL REFLECT THE BEGINNING OF THIS WARM-UP...WITH READINGS
RUNNING SEVERAL DEGREES ABOVE NORMAL BY MONDAY AND TUESDAY. AS
MENTIONED EARLIER...NOT ENTIRELY SOLD YET ON THIS AGGRESSIVE
WARMING...AND STILL PLAUSIBLE FOR BRIEF NORTHERN STREAM FORAYS TO
KEEP THE BULK OF THE WARMING OFF TO OUR WEST.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 638 AM EST WED JAN 2 2013

WIDESPREAD MVFR CIGS WILL BE COMMON FOR EVERYONE WITH FLURRIES AND
NO VSBY RESTRICTIONS. CONFIDENCE IS FAIRLY HIGH HERE. THE MVFR
CIGS WILL GO THROUGH THE NIGHT...ACTUALLY LOWER TO POSSIBLE IFR
LATE TONIGHT WHEN DEEPER MOISTURE AND INCREASING ACTIVE LAKE
EFFECT AND A SLIGHTLY MORE WESTERLY WIND BRINGS IN SOME BETTER
SNOWS. WINDS WILL BE WESTERLY BACKING MORE SW WITH TIME...BUT
10KTS OR LESS.


&&

.MARINE...
ISSUED AT 449 AM EST WED JAN 2 2013

WINDS WILL GRADUALLY WEAKEN TODAY...BEFORE PICKING BACK UP AGAIN
TONIGHT...IN ADVANCE OF AN ALBERTA CLIPPER AND ASSOCIATED COLD
FRONT. THE TIGHTEST GRADIENT WILL RESIDE ACROSS THE NW LOWER
NEARSHORE...THROUGH THE STRAITS AND INTO NRN LAKE HURON. OVERLAKE
INSTABILITY WILL BE DEEPENING WITH THE ABILITY TO TAP ADVISORY
LEVEL GUSTS IN THESE AREAS. IN ADDITION...THIS DEEPENING
INSTABILITY...AND DEEPER MOISTURE FROM THE CLIPPER...WILL RESULT
IN ENHANCED LAKE EFFECT SNOW SHOWERS. THE WINDS WILL BE STRONGEST
BEHIND THE COLD FRONT...THURSDAY THROUGH FRIDAY...AND THESE
ADVISORIES WILL NOT ONLY NEED TO BE EXTENDED...BUT THE REMAINDER
OF THE NEARSHORE WATERS WILL LIKELY NEED ADVISORIES TOO.


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 1 AM EST FRIDAY FOR LHZ345>349.
LM...SMALL CRAFT ADVISORY UNTIL 1 AM EST FRIDAY FOR LMZ323-342-
     344>346.
LS...NONE.

&&

$$

UPDATE...AS
SYNOPSIS...MB
SHORT TERM...SD
LONG TERM...MB
AVIATION...SD
MARINE...SD







AREA FORECAST DISCUSSION

NWS GAYLORD MI

 649 AM EST WED JAN 2 2013

.SYNOPSIS...
ISSUED AT 449 AM EST WED JAN 2 2013

OCCASIONAL LAKE EFFECT SNOW SHOWERS WILL CONTINUE FOR MOST OF THIS
WEEK...WITH A MORE ROBUST PERIOD OF LAKE ENHANCED SNOW THURSDAY...AS
THE NEXT CLIPPER SYSTEM MOVES THROUGH THE AREA. WARMER AND DRIER AIR
THEN BEGIN TO MOVE INTO THE REGION FRIDAY AND OVER THE WEEKEND FOR
SIGNIFICANTLY LOWER SNOW CHANCES.

&&

.UPDATE...
ISSUED AT 638 AM EST WED JAN 2 2013

FORECAST GOING ALONG TO PLAN THIS MORNING WITH FLURRIES IN THE
WESTERLY FLOW REGIMES...EXPANDED FROM INVADING WIDESPREAD LOW
LEVEL STRATUS. THIS STRATUS HAS COVERED ALMOST EVERYONE (ALPENA
WITHIN THE NEXT HOUR OR SO). THERE IS A LOSS OF CONFIDENCE IN THE
DEVELOPMENT OF A PRETTY GOOD BAND OF SNOW OUT OVER LAKE HURON. THE
DRAINAGE FLOW INTO THIS AREA...IS LAGGING BY A FEW HOURS. SO
REMOVED THE HIGH CHANCES FOR SNOW...AND CERTAINLY FOR THE NE LOWER
COAST. WILL HOLD ON TO SOME HOPE BY EARLY AFTERNOON...BUT NOT SO
SURE ABOUT THAT EITHER. ALL OF NRN LOWER SHOULD MAINLY SEE
FLURRIES...UNTIL LATER THIS AFTERNOON...WHEN INCREASING MOISTURE
AND A SW FLOW MAY BRING A FEW TENTHS TO THE NW LOWER COAST.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 449 AM EST WED JAN 2 2013

WEAK HIGH PRESSURE WAS SETTLED IN OVER THE REGION...WITH MUCH
COLDER AIR ACROSS ONTARIO DRAINING IN ACROSS EASTERN LAKE
SUPERIOR...ENHANCING A LOW LEVEL COLD FRONT/CONVERGENCE. THIS
CONVERGENCE AND AIR FLOW OVER LAKE SUPERIOR PRODUCED QUITE THE
MODERATE/INTENSE SNOW BAND THAT FILTERED IN MAINLY JUST THE
PARADISE AREA A FEW HOURS BACK. THIS BAND OF SNOW HAS WEAKENED
OVER EASTERN UPPER DUE TO LOSS OF A DECENT FETCH. THE REST OF NRN
MICHIGAN WAS SEEING A RAPIDLY APPROACHING STRATUS LAYER FROM LAKE
MICHIGAN AND WISCONSIN...WITH A CONTINUED EXPECTATION TO SWEEP
OVER ALL OF THE REGION. CLEAR SKIES IN SPOTS ACROSS FAR NRN LOWER
AND NE LOWER WILL BECOME CLOUDY AGAIN. FLURRIES WERE STILL FAIRLY
PREVALENT OUTSIDE OF THE CLEAR REGIONS...AND THE UPSTREAM CLOUDS
ALSO CONTAIN FLURRIES. RADAR SHOWING THIS IS THE CASE...WITH NEW
ECHOES POPPING UP OVER LAKE MICHIGAN. TEMPERATURES WERE IN THE
TEENS AND LOWER 20S.

NEXT ALBERTA CLIPPER WAS MOVING INTO FAR NRN MN WITH TROUGHING
EXTENDING EASTWARD AND CONNECTING WITH THE ENHANCED TROUGHING FROM
THE COLD AIR DRAINAGE/COLD FRONT. THE SYSTEM COLD FRONT WAS DRAPED
THROUGH EASTERN ND/SD AND DOWN INTO NEBRASKA. DEEPER MOISTURE WAS
SEEN VIA SATELLITE ALONG AND BEHIND THE COLD FRONT...AS WELL
AROUND THE NRN PERIPHERY OF THE LOW PRESSURE.

TODAY AND TONIGHT...WILL BE RAMPING FOR THE ARRIVAL OF THE CLIPPER
LATE TONIGHT AND INTO THURSDAY. THE STRATUS FROM WISCONSIN WAS
ERODING FROM THE SW...WITHIN WEAK WARM AIR ADVECTION INTO THE
CLOUD LAYER. NOT WORRIED TOO MUCH ABOUT THIS WARM ADVECTION
ERODING THE STRATUS FOR US...SINCE LOW LEVEL TEMPS OF -8C TO -10C
HOLD THROUGHOUT THE DAY...SUFFICIENT COLD ENOUGH TO KEEP NOT ONLY
CLOUDS IN PLACE...BUT TO ALSO ALLOW FOR THE CONTINUED GENERATION
OF LAKE EFFECT FLURRIES. THESE FLURRIES WILL BE WITHIN WEST FLOW
REGIMES THIS MORNING...THEN SW FLOW REGIMES AS WINDS BACK AHEAD OF
THE APPROACHING LOW PRESSURE. ONE FLY IN THE OINTMENT THAT COULD
HAVE SOME SIGNIFICANT RAMIFICATIONS IN THE SNOWFALL/AMOUNTS IS FOR
THE DRAINAGE FLOW FROM ONTARIO...EXPECTED TO ENHANCE CONVERGENCE
OVER LAKE HURON...WHICH COULD NEAR THE NE LOWER SHORELINE. HI RES
MODELS/LATEST RUC ARE STEADFAST ON THIS IDEA BY DAYBREAK...WITH
THE DEVELOPMENT OF ANOTHER MODERATE/INTENSE LAKE SNOW BAND.
CONFIDENCE IN THIS ISN`T THE GREATEST...DUE IN PART TO THE
DRAINAGE LAGGING THE HI RES TIMING (NOT EVEN INTO THE SAULT RIGHT
NOW)...AND THAT MIXING INTO THE MORNING MIGHT KEEP THE CONVERGENCE
WELL OUT INTO NRN LAKE HURON...NOT THREATENING OUR COASTAL AREAS.
THIS IS SOMETHING TO KEEP A CLOSE EYE ON...AS THE ARRIVAL OF THE
CONVERGENCE INTO FAR NRN LOWER AND EASTERN UPPER...WOULD ENHANCE
CONVERGENCE AND RESULT IN STRONGER THAN EXPECTED SNOWS.
AGAIN...NOT ENTIRELY SOLD ON THIS. DID INCREASE CHANCES FOR SEEING
BONA FIDE SNOWS AND SMALL ACCUMULATIONS...BUT FEELING IS FOR ANY
ACCUMS TO REMAIN UNDER AN INCH.

WE WILL HAVE TO WAIT FOR INCREASED SW WINDS AND DEEPER MOISTURE
AHEAD OF THE CLIPPER`S COLD FRONT. THIS HAPPENS THROUGH THE
NIGHT...BUT MAINLY AFTER MIDNIGHT. INCREASED MOISTURE FLUX OFF
THE LAKES WILL HELP...BUT INVERSION HEIGHTS RISING TO MAYBE
4500-5000FEET WITH DELTA T`S UNDER 15C...AND NO GOOD SUPPORT ALOFT
WILL MORE LIKELY RESULT IN ACCUMULATIONS IN THE 1-2 INCH RANGE
WITH A SLIVER OF AN AREA ACROSS CENTRAL CHIP/MACK COUNTIES...AND
EMMET COUNTY SEEING UP TO 3 INCHES. IF THERE IS A LAKE HURON BAND
OF SNOW THAT DEVELOP THIS MORNING...THE SW FLOW WILL GRADUALLY
PUSH THIS SNOW IN ACROSS DRUMMOND ISLAND BEFORE DEPARTING EAST OF
THERE. VERY DIFFICULT MESOSCALE FORECAST IN THE SHORT TERM.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 449 AM EST WED JAN 2 2013

ENERGETIC SPLIT FLOW PATTERN SET TO CONTINUE...WITH ONE LAST
NORTHERN STREAM ORIGINATED SHORTWAVE SET TO VISIT OUR AREA LATER
TONIGHT INTO THURSDAY. AFTERWARD...NORTHERN STREAM PROGGED TO
RETREAT NORTH...BOTTLING UP THE ARCTIC COLD WELL TO OUR NORTH FOR
THE FORESEEABLE FUTURE...PART OF A BURGEONING POSITIVE AO SIGNATURE
AND EAST DISPLACED NORTH ATLANTIC BLOCKING. NOT TO SAY THE PATTERN
DOESN`T HOLD AT LEAST SOME SNOW POTENTIAL FOR THE SNOW ENTHUSIASTS
AMONGST US...WITH THURSDAY`S LEAD CHARGING SYSTEM HAVING THE LOOKS
OF A RATHER SNEAKY LAKE ENHANCED SNOW EVENT FOR THE TRADITIONAL
SNOWBELTS. TAKING A LOOK EVEN FURTHER OUT...MAY SEE THE BEGINNINGS
OF THE INFAMOUS "JANUARY THAW" HEADING INTO NEXT WORK WEEK...WITH
WELL AGREED UPON PROGS SUGGESTING A FURTHER RELAXATION OF THE
NORTHERN STREAM AND A FLOODING OF MODIFIED PACIFIC AIR ACROSS THE
CONUS. LARGE SCALE INDICES WOULD TEND TO AGREE...ALTHOUGH WITH
DOMINATE POLAR VORTEX ON THIS SIDE OF THE GLOBE...HAVE SOME
SUSPICION NORTHERN STREAM WILL NOT YIELD AS AGGRESSIVELY AS SOME
PROGS WOULD SUGGEST. GETTING A TOUCH AHEAD OF MYSELF...AND STILL
HAVE AMPLE CONCERNS IN THE SHORT TERM PORTION OF THE LONG TERM TO
DEAL WITH...MOST NOTABLY THURSDAY`S SNOW POTENTIAL.

DEFINITELY AN INTRIGUING SYSTEM FOR THURSDAY AS FAST MOVING AREA OF
LOW PRESSURE SLICES ACROSS LAKE SUPERIOR EARLY...DRAGGING AN EQUALLY
FAST MOVING COLD FRONT THROUGH NORTHERN MICHIGAN DURING THE MORNING.
WHILE CORE OF BETTER MID LEVEL DYNAMICS LOOK TO PASS BY JUST TO OUR
NORTH..STILL DECENT SLUG OF UPWARD QG SUPPORT ALONG SHARP SHORTWAVE
TROUGH AXIS PASSING OVERHEAD. DEEP LAYER MOISTURE NOTHING TO WRITE
HOME ABOUT...WITH PWAT VALUES STRUGGLING TO EXCEED A QUARTER OF AN
INCH. STILL...WOULD EXPECT AT LEAST SOME SYNOPTIC DRIVEN SNOWS TO
ACCOMPANY SHORTWAVE PASSAGE DURING THE MORNING. WILD CARD REMAINS
LAKE ENHANCEMENT POTENTIAL...BOTH ALONG AND PROCEEDING COLD FRONTAL
PASSAGE. PREFRONTAL AIRMASS MORE THAN COLD ENOUGH TO SUPPORT LAKE
ENHANCED SNOWS...PARTICULARLY AS CONVERGENCE IS MAXIMIZED ALONG
FRONTAL SLOPE. TEMPERATURES COOL FURTHER IMMEDIATELY BEHIND THE
FRONT...WITH H85 READINGS APPROACHING THE NEGATIVE MIDDLE TEENS BY
AFTERNOON. MOISTURE REMAINS ABUNDANT UNTIL MID LEVEL TROUGH PASSAGE
DURING THE AFTERNOON...SUGGESTING AT LEAST A SEVERAL HOUR WINDOW OF
GOOD LAKE ENHANCED SNOWS IN FAVORED WNW-NW FLOW AREAS THROUGH THE
MORNING. MODEL DERIVED SOUNDING BEAR THIS POTENTIAL OUT (ESPECIALLY
NAM-BUFR SOUNDINGS WHICH HAVE SOME SUPPORT FROM LATEST ECMWF
PROGS)...WITH QUICK UPTICK TO NEAR H75 INVERSION LEVELS...ALL THE
WHILE OMEGA MAX BECOMES CENTERED IN PRIME DGZ. HOW WILL ALL THIS
PLAY OUT? KINDA ENVISION A PERIOD OF DECENT SNOWS ACROSS NORTHWEST
LOWER/EASTERN UPPER MICHIGAN WITH THE FRONTAL PASSAGE...WITH A QUICK
TRANSITION TO WNW-NW LAKE ENHANCED SNOWS THROUGH THE REMAINDER OF
THE MORNING. ACTIVITY SHOULD BEGIN TO WIND DOWN RATHER QUICKLY
DURING THE AFTERNOON...AND ESPECIALLY THURSDAY EVENING...AS MOISTURE
RAPIDLY DEPARTS. CIPS ANALOGS FOR THIS EVENT HONING IN ON SOME
INTERESTING NUMBERS...WITH IMPACT GUIDANCE SHOWING 6 TO 8 INCH
AMOUNTS IN THE TRADITIONAL SNOWBELTS OF BOTH PENINSULAS. QUICK
MOVEMENT OF SYSTEM AND SOME LINGERING CONCERN WITH EXACT THERMAL
STRUCTURES (SOME GUIDANCE NOT QUITE AS COLD) PREVENTS FROM GOING
THIS AGGRESSIVE...BUT WILL GO AHEAD A RAISE INHERITED SNOW AMOUNTS
BY AT LEAST AN INCH OR SO...BRINGING DAYTIME ACCUMULATIONS TO 2 TO 3
INCHES IN FAVORED AREAS. IF TRENDS HOLD...MAY EVENTUALLY NEED AN
ADVISORY FOR AT LEAST SOME COUNTIES OF NORTHWEST LOWER AND EASTERN
UPPER MICHIGAN. SYSTEM EXITS JUST AS QUICK AS IT ARRIVES...WITH ANY
LINGERING SNOW SHOWERS COMING TO AN END OVERNIGHT THURSDAY AS MOISTURE
DEPARTS AND WAA COMMENCES.

CONDITIONS LOOK QUIET AND A TOUCH WARMER TO END THE WORK WEEK AS THE
NORTHERN STREAM RELAXATION BEGINS...LETTING HEIGHTS BUILD AND
SOUTHWEST WINDS TO DEVELOP ON NORTH SIDE OF SOUTHERN HIGH PRESSURE.
NEXT MOISTURE STARVED SYSTEM ARRIVES OVER THE WEEKEND...PERHAPS
BRINGING A FEW SNOW SHOWERS ONCE AGAIN SATURDAY INTO SATURDAY NIGHT.
TEMPERATURES APPEAR TOO MARGINAL FOR ANY PRE AND POST FRONTAL LAKE
ENHANCEMENT. MAIN STORM TRACK CONTINUES TO TREND FURTHER NORTH
HEADING INTO NEXT WORK WEEK. PACIFIC AIR STILL APPEARS RATHER
AGGRESSIVE...WITH LATEST PROGS SUGGESTING MUCH OF THE NORTHERN CONUS
FLOODED BY ABOVE NORMAL TEMPERATURES BY THE MIDDLE OF NEXT WEEK.
FORECAST WILL REFLECT THE BEGINNING OF THIS WARM-UP...WITH READINGS
RUNNING SEVERAL DEGREES ABOVE NORMAL BY MONDAY AND TUESDAY. AS
MENTIONED EARLIER...NOT ENTIRELY SOLD YET ON THIS AGGRESSIVE
WARMING...AND STILL PLAUSIBLE FOR BRIEF NORTHERN STREAM FORAYS TO
KEEP THE BULK OF THE WARMING OFF TO OUR WEST.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 638 AM EST WED JAN 2 2013

WIDESPREAD MVFR CIGS WILL BE COMMON FOR EVERYONE WITH FLURRIES AND
NO VSBY RESTRICTIONS. CONFIDENCE IS FAIRLY HIGH HERE. THE MVFR
CIGS WILL GO THROUGH THE NIGHT...ACTUALLY LOWER TO POSSIBLE IFR
LATE TONIGHT WHEN DEEPER MOISTURE AND INCREASING ACTIVE LAKE
EFFECT AND A SLIGHTLY MORE WESTERLY WIND BRINGS IN SOME BETTER
SNOWS. WINDS WILL BE WESTERLY BACKING MORE SW WITH TIME...BUT
10KTS OR LESS.

&&

.MARINE...
ISSUED AT 449 AM EST WED JAN 2 2013

WINDS WILL GRADUALLY WEAKEN TODAY...BEFORE PICKING BACK UP AGAIN
TONIGHT...IN ADVANCE OF AN ALBERTA CLIPPER AND ASSOCIATED COLD
FRONT. THE TIGHTEST GRADIENT WILL RESIDE ACROSS THE NW LOWER
NEARSHORE...THROUGH THE STRAITS AND INTO NRN LAKE HURON. OVERLAKE
INSTABILITY WILL BE DEEPENING WITH THE ABILITY TO TAP ADVISORY
LEVEL GUSTS IN THESE AREAS. IN ADDITION...THIS DEEPENING
INSTABILITY...AND DEEPER MOISTURE FROM THE CLIPPER...WILL RESULT
IN ENHANCED LAKE EFFECT SNOW SHOWERS. THE WINDS WILL BE STRONGEST
BEHIND THE COLD FRONT...THURSDAY THROUGH FRIDAY...AND THESE
ADVISORIES WILL NOT ONLY NEED TO BE EXTENDED...BUT THE REMAINDER
OF THE NEARSHORE WATERS WILL LIKELY NEED ADVISORIES TOO.


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 1 AM EST FRIDAY FOR LHZ345>349.
LM...SMALL CRAFT ADVISORY UNTIL 1 AM EST FRIDAY FOR LMZ323-342-
     344>346.
LS...NONE.

&&

$$

UPDATE...SD
SYNOPSIS...MB
SHORT TERM...SD
LONG TERM...MB
AVIATION...SD
MARINE...SD







AREA FORECAST DISCUSSION

NWS GAYLORD MI

 501 AM EST WED JAN 2 2013

.SYNOPSIS...
ISSUED AT 449 AM EST WED JAN 2 2013

OCCASIONAL LAKE EFFECT SNOW SHOWERS WILL CONTINUE FOR MOST OF THIS
WEEK...WITH A MORE ROBUST PERIOD OF LAKE ENHANCED SNOW THURSDAY...AS
THE NEXT CLIPPER SYSTEM MOVES THROUGH THE AREA. WARMER AND DRIER AIR
THEN BEGIN TO MOVE INTO THE REGION FRIDAY AND OVER THE WEEKEND FOR
SIGNIFICANTLY LOWER SNOW CHANCES.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 449 AM EST WED JAN 2 2013

WEAK HIGH PRESSURE WAS SETTLED IN OVER THE REGION...WITH MUCH
COLDER AIR ACROSS ONTARIO DRAINING IN ACROSS EASTERN LAKE
SUPERIOR...ENHANCING A LOW LEVEL COLD FRONT/CONVERGENCE. THIS
CONVERGENCE AND AIR FLOW OVER LAKE SUPERIOR PRODUCED QUITE THE
MODERATE/INTENSE SNOW BAND THAT FILTERED IN MAINLY JUST THE
PARADISE AREA A FEW HOURS BACK. THIS BAND OF SNOW HAS WEAKENED
OVER EASTERN UPPER DUE TO LOSS OF A DECENT FETCH. THE REST OF NRN
MICHIGAN WAS SEEING A RAPIDLY APPROACHING STRATUS LAYER FROM LAKE
MICHIGAN AND WISCONSIN...WITH A CONTINUED EXPECTATION TO SWEEP
OVER ALL OF THE REGION. CLEAR SKIES IN SPOTS ACROSS FAR NRN LOWER
AND NE LOWER WILL BECOME CLOUDY AGAIN. FLURRIES WERE STILL FAIRLY
PREVALENT OUTSIDE OF THE CLEAR REGIONS...AND THE UPSTREAM CLOUDS
ALSO CONTAIN FLURRIES. RADAR SHOWING THIS IS THE CASE...WITH NEW
ECHOES POPPING UP OVER LAKE MICHIGAN. TEMPERATURES WERE IN THE
TEENS AND LOWER 20S.

NEXT ALBERTA CLIPPER WAS MOVING INTO FAR NRN MN WITH TROUGHING
EXTENDING EASTWARD AND CONNECTING WITH THE ENHANCED TROUGHING FROM
THE COLD AIR DRAINAGE/COLD FRONT. THE SYSTEM COLD FRONT WAS DRAPED
THROUGH EASTERN ND/SD AND DOWN INTO NEBRASKA. DEEPER MOISTURE WAS
SEEN VIA SATELLITE ALONG AND BEHIND THE COLD FRONT...AS WELL
AROUND THE NRN PERIPHERY OF THE LOW PRESSURE.

TODAY AND TONIGHT...WILL BE RAMPING FOR THE ARRIVAL OF THE CLIPPER
LATE TONIGHT AND INTO THURSDAY. THE STRATUS FROM WISCONSIN WAS
ERODING FROM THE SW...WITHIN WEAK WARM AIR ADVECTION INTO THE
CLOUD LAYER. NOT WORRIED TOO MUCH ABOUT THIS WARM ADVECTION
ERODING THE STRATUS FOR US...SINCE LOW LEVEL TEMPS OF -8C TO -10C
HOLD THROUGHOUT THE DAY...SUFFICIENT COLD ENOUGH TO KEEP NOT ONLY
CLOUDS IN PLACE...BUT TO ALSO ALLOW FOR THE CONTINUED GENERATION
OF LAKE EFFECT FLURRIES. THESE FLURRIES WILL BE WITHIN WEST FLOW
REGIMES THIS MORNING...THEN SW FLOW REGIMES AS WINDS BACK AHEAD OF
THE APPROACHING LOW PRESSURE. ONE FLY IN THE OINTMENT THAT COULD
HAVE SOME SIGNIFICANT RAMIFICATIONS IN THE SNOWFALL/AMOUNTS IS FOR
THE DRAINAGE FLOW FROM ONTARIO...EXPECTED TO ENHANCE CONVERGENCE
OVER LAKE HURON...WHICH COULD NEAR THE NE LOWER SHORELINE. HI RES
MODELS/LATEST RUC ARE STEADFAST ON THIS IDEA BY DAYBREAK...WITH
THE DEVELOPMENT OF ANOTHER MODERATE/INTENSE LAKE SNOW BAND.
CONFIDENCE IN THIS ISN`T THE GREATEST...DUE IN PART TO THE
DRAINAGE LAGGING THE HI RES TIMING (NOT EVEN INTO THE SAULT RIGHT
NOW)...AND THAT MIXING INTO THE MORNING MIGHT KEEP THE CONVERGENCE
WELL OUT INTO NRN LAKE HURON...NOT THREATENING OUR COASTAL AREAS.
THIS IS SOMETHING TO KEEP A CLOSE EYE ON...AS THE ARRIVAL OF THE
CONVERGENCE INTO FAR NRN LOWER AND EASTERN UPPER...WOULD ENHANCE
CONVERGENCE AND RESULT IN STRONGER THAN EXPECTED SNOWS.
AGAIN...NOT ENTIRELY SOLD ON THIS. DID INCREASE CHANCES FOR SEEING
BONA FIDE SNOWS AND SMALL ACCUMULATIONS...BUT FEELING IS FOR ANY
ACCUMS TO REMAIN UNDER AN INCH.

WE WILL HAVE TO WAIT FOR INCREASED SW WINDS AND DEEPER MOISTURE
AHEAD OF THE CLIPPER`S COLD FRONT. THIS HAPPENS THROUGH THE
NIGHT...BUT MAINLY AFTER MIDNIGHT. INCREASED MOISTURE FLUX OFF
THE LAKES WILL HELP...BUT INVERSION HEIGHTS RISING TO MAYBE
4500-5000FEET WITH DELTA T`S UNDER 15C...AND NO GOOD SUPPORT ALOFT
WILL MORE LIKELY RESULT IN ACCUMULATIONS IN THE 1-2 INCH RANGE
WITH A SLIVER OF AN AREA ACROSS CENTRAL CHIP/MACK COUNTIES...AND
EMMET COUNTY SEEING UP TO 3 INCHES. IF THERE IS A LAKE HURON BAND
OF SNOW THAT DEVELOP THIS MORNING...THE SW FLOW WILL GRADUALLY
PUSH THIS SNOW IN ACROSS DRUMMOND ISLAND BEFORE DEPARTING EAST OF
THERE. VERY DIFFICULT MESOSCALE FORECAST IN THE SHORT TERM.


&&

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 449 AM EST WED JAN 2 2013

ENERGETIC SPLIT FLOW PATTERN SET TO CONTINUE...WITH ONE LAST
NORTHERN STREAM ORIGINATED SHORTWAVE SET TO VISIT OUR AREA LATER
TONIGHT INTO THURSDAY. AFTERWARD...NORTHERN STREAM PROGGED TO
RETREAT NORTH...BOTTLING UP THE ARCTIC COLD WELL TO OUR NORTH FOR
THE FORESEEABLE FUTURE...PART OF A BURGEONING POSITIVE AO SIGNATURE
AND EAST DISPLACED NORTH ATLANTIC BLOCKING. NOT TO SAY THE PATTERN
DOESN`T HOLD AT LEAST SOME SNOW POTENTIAL FOR THE SNOW ENTHUSIASTS
AMONGST US...WITH THURSDAY`S LEAD CHARGING SYSTEM HAVING THE LOOKS
OF A RATHER SNEAKY LAKE ENHANCED SNOW EVENT FOR THE TRADITIONAL
SNOWBELTS. TAKING A LOOK EVEN FURTHER OUT...MAY SEE THE BEGINNINGS
OF THE INFAMOUS "JANUARY THAW" HEADING INTO NEXT WORK WEEK...WITH
WELL AGREED UPON PROGS SUGGESTING A FURTHER RELAXATION OF THE
NORTHERN STREAM AND A FLOODING OF MODIFIED PACIFIC AIR ACROSS THE
CONUS. LARGE SCALE INDICES WOULD TEND TO AGREE...ALTHOUGH WITH
DOMINATE POLAR VORTEX ON THIS SIDE OF THE GLOBE...HAVE SOME
SUSPICION NORTHERN STREAM WILL NOT YIELD AS AGGRESSIVELY AS SOME
PROGS WOULD SUGGEST. GETTING A TOUCH AHEAD OF MYSELF...AND STILL
HAVE AMPLE CONCERNS IN THE SHORT TERM PORTION OF THE LONG TERM TO
DEAL WITH...MOST NOTABLY THURSDAY`S SNOW POTENTIAL.

DEFINITELY AN INTRIGUING SYSTEM FOR THURSDAY AS FAST MOVING AREA OF
LOW PRESSURE SLICES ACROSS LAKE SUPERIOR EARLY...DRAGGING AN EQUALLY
FAST MOVING COLD FRONT THROUGH NORTHERN MICHIGAN DURING THE MORNING.
WHILE CORE OF BETTER MID LEVEL DYNAMICS LOOK TO PASS BY JUST TO OUR
NORTH..STILL DECENT SLUG OF UPWARD QG SUPPORT ALONG SHARP SHORTWAVE
TROUGH AXIS PASSING OVERHEAD. DEEP LAYER MOISTURE NOTHING TO WRITE
HOME ABOUT...WITH PWAT VALUES STRUGGLING TO EXCEED A QUARTER OF AN
INCH. STILL...WOULD EXPECT AT LEAST SOME SYNOPTIC DRIVEN SNOWS TO
ACCOMPANY SHORTWAVE PASSAGE DURING THE MORNING. WILD CARD REMAINS
LAKE ENHANCEMENT POTENTIAL...BOTH ALONG AND PROCEEDING COLD FRONTAL
PASSAGE. PREFRONTAL AIRMASS MORE THAN COLD ENOUGH TO SUPPORT LAKE
ENHANCED SNOWS...PARTICULARLY AS CONVERGENCE IS MAXIMIZED ALONG
FRONTAL SLOPE. TEMPERATURES COOL FURTHER IMMEDIATELY BEHIND THE
FRONT...WITH H85 READINGS APPROACHING THE NEGATIVE MIDDLE TEENS BY
AFTERNOON. MOISTURE REMAINS ABUNDANT UNTIL MID LEVEL TROUGH PASSAGE
DURING THE AFTERNOON...SUGGESTING AT LEAST A SEVERAL HOUR WINDOW OF
GOOD LAKE ENHANCED SNOWS IN FAVORED WNW-NW FLOW AREAS THROUGH THE
MORNING. MODEL DERIVED SOUNDING BEAR THIS POTENTIAL OUT (ESPECIALLY
NAM-BUFR SOUNDINGS WHICH HAVE SOME SUPPORT FROM LATEST ECMWF
PROGS)...WITH QUICK UPTICK TO NEAR H75 INVERSION LEVELS...ALL THE
WHILE OMEGA MAX BECOMES CENTERED IN PRIME DGZ. HOW WILL ALL THIS
PLAY OUT? KINDA ENVISION A PERIOD OF DECENT SNOWS ACROSS NORTHWEST
LOWER/EASTERN UPPER MICHIGAN WITH THE FRONTAL PASSAGE...WITH A QUICK
TRANSITION TO WNW-NW LAKE ENHANCED SNOWS THROUGH THE REMAINDER OF
THE MORNING. ACTIVITY SHOULD BEGIN TO WIND DOWN RATHER QUICKLY
DURING THE AFTERNOON...AND ESPECIALLY THURSDAY EVENING...AS MOISTURE
RAPIDLY DEPARTS. CIPS ANALOGS FOR THIS EVENT HONING IN ON SOME
INTERESTING NUMBERS...WITH IMPACT GUIDANCE SHOWING 6 TO 8 INCH
AMOUNTS IN THE TRADITIONAL SNOWBELTS OF BOTH PENINSULAS. QUICK
MOVEMENT OF SYSTEM AND SOME LINGERING CONCERN WITH EXACT THERMAL
STRUCTURES (SOME GUIDANCE NOT QUITE AS COLD) PREVENTS FROM GOING
THIS AGGRESSIVE...BUT WILL GO AHEAD A RAISE INHERITED SNOW AMOUNTS
BY AT LEAST AN INCH OR SO...BRINGING DAYTIME ACCUMULATIONS TO 2 TO 3
INCHES IN FAVORED AREAS. IF TRENDS HOLD...MAY EVENTUALLY NEED AN
ADVISORY FOR AT LEAST SOME COUNTIES OF NORTHWEST LOWER AND EASTERN
UPPER MICHIGAN. SYSTEM EXITS JUST AS QUICK AS IT ARRIVES...WITH ANY
LINGERING SNOW SHOWERS COMING TO AN END OVERNIGHT THURSDAY AS MOISTURE
DEPARTS AND WAA COMMENCES.

CONDITIONS LOOK QUIET AND A TOUCH WARMER TO END THE WORK WEEK AS THE
NORTHERN STREAM RELAXATION BEGINS...LETTING HEIGHTS BUILD AND
SOUTHWEST WINDS TO DEVELOP ON NORTH SIDE OF SOUTHERN HIGH PRESSURE.
NEXT MOISTURE STARVED SYSTEM ARRIVES OVER THE WEEKEND...PERHAPS
BRINGING A FEW SNOW SHOWERS ONCE AGAIN SATURDAY INTO SATURDAY NIGHT.
TEMPERATURES APPEAR TOO MARGINAL FOR ANY PRE AND POST FRONTAL LAKE
ENHANCEMENT. MAIN STORM TRACK CONTINUES TO TREND FURTHER NORTH
HEADING INTO NEXT WORK WEEK. PACIFIC AIR STILL APPEARS RATHER
AGGRESSIVE...WITH LATEST PROGS SUGGESTING MUCH OF THE NORTHERN CONUS
FLOODED BY ABOVE NORMAL TEMPERATURES BY THE MIDDLE OF NEXT WEEK.
FORECAST WILL REFLECT THE BEGINNING OF THIS WARM-UP...WITH READINGS
RUNNING SEVERAL DEGREES ABOVE NORMAL BY MONDAY AND TUESDAY. AS
MENTIONED EARLIER...NOT ENTIRELY SOLD YET ON THIS AGGRESSIVE
WARMING...AND STILL PLAUSIBLE FOR BRIEF NORTHERN STREAM FORAYS TO
KEEP THE BULK OF THE WARMING OFF TO OUR WEST.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1140 PM EST TUE JAN 1 2013

MVFR CONDITIONS ARE EXPECTED TO CONTINUE FOR THE TERMINAL SITES
THE REST OF THE NIGHT...THOUGH WITH A BRIEF PERIOD OF CLEARING
POSSIBLE AROUND PLN THE NEXT FEW HOURS. CEILINGS WILL PROBABLY
GRADUALLY LOWER AFTER 08Z AS THICKER STRATUS ACROSS WISCONSIN
DRIFTS INTO THE REGION...WITH A SMALL POTENTIAL FOR A BRIEF PERIOD
OF IFR AROUND TVC/MBL. PERIODIC FLURRIES WILL ALSO CONTINUE FOR
JUST ABOUT ALL SITES...BUT WITH VISBYS NO WORSE THAN 5-6SM. THAT
MAY CHANGE A BIT ACROSS NORTHWEST LOWER MICHIGAN LATER WEDNESDAY
AS THE FLOW BACKS MORE SOUTHWESTERLY...PERHAPS BRINGING SOME
SLIGHTLY MORE ROBUST SNOW SHOWERS AROUND PLN AND MAYBE TVC/MBL.
WINDS THROUGH THE PERIOD SHOULD BE FAIRLY LIGHT...GENERALLY IN THE
5-15 KNOT RANGE.


&&

.MARINE...
ISSUED AT 449 AM EST WED JAN 2 2013

WINDS WILL GRADUALLY WEAKEN TODAY...BEFORE PICKING BACK UP AGAIN
TONIGHT...IN ADVANCE OF AN ALBERTA CLIPPER AND ASSOCIATED COLD
FRONT. THE TIGHTEST GRADIENT WILL RESIDE ACROSS THE NW LOWER
NEARSHORE...THROUGH THE STRAITS AND INTO NRN LAKE HURON. OVERLAKE
INSTABILITY WILL BE DEEPENING WITH THE ABILITY TO TAP ADVISORY
LEVEL GUSTS IN THESE AREAS. IN ADDITION...THIS DEEPENING
INSTABILITY...AND DEEPER MOISTURE FROM THE CLIPPER...WILL RESULT
IN ENHANCED LAKE EFFECT SNOW SHOWERS. THE WINDS WILL BE STRONGEST
BEHIND THE COLD FRONT...THURSDAY THROUGH FRIDAY...AND THESE
ADVISORIES WILL NOT ONLY NEED TO BE EXTENDED...BUT THE REMAINDER
OF THE NEARSHORE WATERS WILL LIKELY NEED ADVISORIES TOO.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 1 AM EST FRIDAY FOR LHZ345>349.
LM...SMALL CRAFT ADVISORY UNTIL 1 AM EST FRIDAY FOR LMZ323-342-
     344>346.
LS...NONE.

&&

$$

SYNOPSIS...MB
SHORT TERM...SD
LONG TERM...MB
AVIATION...LAWRENCE
MARINE...SD







AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

 611 AM CST WED JAN 2 2013

.UPDATE...FOR 12Z AVIATION DISCUSSION BELOW

&&

.DISCUSSION.../ISSUED 227 AM CST WED JAN 2 2013/

MAIN FORECAST CONCERN IS WHETHER THERE IS ENOUGH ENERGY TO
GENERATE LIGHT SNOW ACROSS THE FA THIS MORNING...AND INTO EARLY
THIS EVENING.

WEAK AND UNORGANIZED RETURNS FROM REGIONAL RADAR AND THE LACK OF
ANY COOLING OR ENHANCEMENT OF UPSTREAM CLDS...HAS ME WONDER IF
LIKELY POPS ARE TOO HIGH FOR TODAY...ESPECIALLY CONSIDERING THE
SFC LOW WILL BE WELL NORTH OF OUR FA...AND DEEPER MOISTURE RESIDES
BEHIND THE MAIN FRONTAL BOUNDARY ACROSS THE EASTERN DAKOTAS. IN
ADDITION...SOME OF THE LOCAL WRF MODELS REFLECTIVITY IMAGERY HAS
ALMOST LITTLE RETURNS OR NOTHING HIGHER THAN 15 DBZ...AND MAINLY FOR
WC/CENTRAL MN BEFORE 18Z. THIS SEEMS TO BE REASONABLE BASED ON THE
LATEST REGIONAL RADAR RETURNS ACROSS THE EASTERN DAKOTAS. BUT
UNDER THE WEAK RETURNS...NEARLY NO RESTRICTIONS TO VSBY IN -SN WAS
NOTED. THE ONLY CONTINUATION FOR THE LIKELY POPS IS DEEPER
MOISTURE BEHIND THE FRONT ALONG THE -15C ZONE...AND A SLIGHT
INCREASE IN PVA WHICH MAY ENHANCE OUR REGION LATER THIS AFTN/EARLY
EVENING. EVEN WITH THE LIKELY POPS...QPF AMTS WILL BE VERY LOW AND
UNDER 0.03 WHICH LEADS TO A DUSTING OR UP TO AN HALF INCH IN SOME
LOCATIONS ACROSS WEST-CENTRAL AND CENTRAL MN THIS MORNING.

AFTER TONIGHT...NO FORECAST CONCERNS AS THE MEAN PATTERN BECOMES
QUIET FOR OUR REGION WITH THE MAIN STORM TRACK WELL NORTH AND
SOUTH OF THE FA. AS MORE PACIFIC TYPE AIR MASSES BEGIN TO SPILL
OVER THE ROCKIES...AND INTO THE NORTHERN PLAINS/UPPER
MIDWEST...EXPECT OUR REGION TO BEGIN TO MODIFY IN TERMS OF TEMPS
WITH NEAR FREEZING HIGHS ON FRIDAY...AND NEXT WEEK. BOTH THE
EC/GFS HAVE A SPLIT FLOW TYPE OF UPPER AIR PATTERN WHICH WILL
LIKELY BE CHAOTIC WITH EACH RUN PAST FIVE DAYS. THERE IS SOME
SIGNS OF A STORM DEVELOPING ACROSS THE SOUTHERN U.S. LATE NEXT
WEEK...WHICH MAY BEGIN TO AFFECT OUR REGION BY THE WEEKEND OF THE
12TH.

THE CURRENT RUN OF THE NAEFS AND CFS CLIMATE MODEL DOES SUPPORT
THE ABOVE NORMAL TEMPS NEXT WEEK. HOWEVER...THERE HAS BEEN A TREND
TO COOL THINGS DOWN AGAIN BY THE THIRD AND FOURTH WEEK OF JANUARY.
ALSO LOOKING AT THE CFSV2 FORECAST OF MONTHLY CLIMATE ANOMALIES
FOR FEBRUARY DOES HAVE A STRONG SIGNAL OF COLDER AND WETTER PATTERN
DEVELOPING. TIME WILL TELL! ..JLT..

&&

.AVIATION.../12Z TAF ISSUANCE/

WIDESPREAD IFR/MVFR CONDITIONS WILL OCCUR TODAY AHEAD OF THE SFC
LOW THAT WAS CENTERED OVER THE NWRN CORNER OF MN AT 12Z. WHILE A
CLEAR SLOT DEVELOPED OVER WEST/SOUTH CENTRAL MN OVERNIGHT...EXPECT
THIS TO FILL BACK IN OVER THE NEXT FEW HOURS AS THE LOW BEGINS TO
SINK SOUTHEAST ACROSS NORTHERN/CENTRAL MN. THE OTHER NEAR-TERM
CONCERN IS FOG...AS EXHIBITED BY VSBYS IN THE 1SM-3SM RANGE OVER
SOUTH CENTRAL MN. THIS POCKET OF REDUCED VSBYS IS BEING ANALYZED
FAIRLY WELL BY THE RAP AND HRRR MODELS...WHICH PROG THE AREA OF
REDUCED VSBYS TO ADVECT NORTHWARD THIS MORNING. THINK VSBYS WILL
OCCASIONALLY DIP TO IFR BETWEEN 12Z AND 17Z IN CENTRAL/EAST
CENTRAL MN. SNOW ASSOCIATED WITH THE AFOREMENTIONED LOW WILL BEGIN
AT AXN SHORTLY AFTER THE TAF PERIOD BEGINS AND REACH KSTC/KRWF BY
LATE MORNING. KMSP SHOULD SEE LIGHT SNOW BY 20Z...AND KRNH/KEAU BY
22Z. PREVALENT MVFR VSBYS ARE EXPECTED TO ACCOMPANY THE LIGHT
SNOW...WITH TEMPORARY IFR VSYBS TO AROUND 2SM THE MOST POSSIBLE AT
WESTERN SITES /KAXN AND KRWF/. THE SNOW SHOULD TAPER OFF THIS
EVENING...ALTHOUGH MVFR CIGS WILL LIKELY PERSIST INTO THURSDAY.
NORTHWEST WINDS ARE EXPECTED TO GUST INTO THE MID/UPPER TEENS
/KNOTS/ IN THE WAKE OF THE FRONT.

KMSP...POCKET OF FOG WITH VSBYS OF 1-3SM AND CIGS AROUND 500 FT
WILL PLAGUE KMSP THIS MORNING. VSBYS SHOULD IMPROVE TO AROUND 5SM
BY THIS AFTERNOON...WITH -SN EXPECTED TO BEGIN AROUND 20Z AS THE
FRONT ARRIVES. WINDS SHOULD SHIFT TO NORTHWEST AFTER 00Z...WITH
GUSTS TO AROUND 17KTS POSSIBLE TONIGHT. SHOULD SEE GRADUAL IMPROVEMENT
IN CIGS TONIGHT...ALTHOUGH WILL LIKELY NOT CLEAR OUT THE OVC 3KFT DECK.

/OUTLOOK FOR KMSP/
THU...VFR. WINDS NW AT 10G15KTS.
FRI...VFR. WINDS SW AT 5 TO 10KTS.
SAT...VFR WITH MVFR CIGS AND -SN POSSIBLE. WINDS NW AT 5 TO 15KTS.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&

$$

JLT/LS






AREA FORECAST DISCUSSION...UPDATED

NWS GLASGOW MT

 924 AM MST WED JAN 2 2013

.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH FRIDAY...
A LARGE-SCALE UPPER LEVEL RIDGE BUILDING UP OVER THE WEST WILL
PUSH THE REMNANTS OF THE TROUGH TO THE EAST TODAY. SNOW SHOWERS
ARE STILL SHOWING UP THIS MORNING ON THE RADAR...MAINLY EAST OF
GGW. ADJUSTED POPS ACCORDINGLY WITH LOW QPF. OTHERWISE SPREAD
OVERCAST SKIES TO THE WEST FOR THIS MORNING BASED ON WR FOG/REFL
PRODUCT. A STRONG SURFACE TROUGH LOCATED OVER NORTH DAKOTA WILL
MAINTAIN GUSTY WINDS TODAY. HOWEVER AS THE TROUGH MOVES FARTHER
EAST...THE NW WIND WILL DIMINISH IN STRENGTH FROM THE WEST.
UPDATED WINDS WITH LATEST GUIDANCE. SCT

PREVIOUS DISCUSSION...
A DIFFICULT BEGINNING TO THE FORECAST THIS MORNING ACROSS
NORTHEAST MONTANA. A FEW SNOW SHOWERS ARE FLOATING AROUND THE
SOUTHERN ZONES...BUT UPSTREAM FAIRLY CLEAR VIA THE IR SAT THIS
MORNING. BETHUNE AND SCHULER RADARS TO OUR NORTH HAVE THE SNOW
SHOWERS MAINLY EAST OF ASSININBOIA THIS MORNING TRACKING
SOUTHEAST. WILL KEEP THE HIGHER POPS ALONG THE NORTH DAKOTA BORDER
EVEN THOUGH CONFIDENCE IS FALLING OFF QUICKLY WITH THE NAM/GFS AS
PER THE HRRR WHICH KEEPS THE AREA DRY THROUGH THE MORNING HOURS.
IF THE EAST STARTS TO CLEAR MIGHT HAVE TO MAKE AN EARLY MORNING
UPDATE TO IMPROVE THE WEATHER IN THE EAST TODAY.

BY TONIGHT THE RIDGE BUILDS IN...AS PER ALL GUIDANCE PRODUCTS
WHICH WILL DRY THE AREA OUT ABOVE 2700 FEET IN THE ATMOSPHERE
AND BEGIN TO WARM IT UP AT THE HIGHER ELEVATIONS. THE LOWER
ELEVATIONS WILL STAY BELOW THE INVERSION AND IN THE SHALLOW COLD
AIR WILL LOOKS TO HANG ON UNTIL FRIDAY. MAKES FOR A DIFFICULT
TEMPERATURE FORECAST... ABOVE 3000 FEET 30S AND 40S LOOK GOOD...
BELOW 2500 SORRY BUT LOOKS FOR THE TEENS AND 20S WITH OVERNIGHT
LOWS IN THE SINGLE DIGITS. ITS THE IN BETWEEN THOSE TWO ELEVATIONS
THAT WILL BOUNCE AROUND.

FRIDAY THE RIDGE GETS FLATTENED BY A DRY SHORTWAVE WHICH SHOULD
ALLOW MIXING DOWN INTO THE VALLEYS AND ALLOW THE VALLEY BOTTOM
LOCATIONS TO ENJOY A LITTLE WARMER AIR... CHINOOK WINDS SHOULD
KICK UP IN THE WESTERN ZONES AND HIGHER ELEVATIONS IN THE EAST
WITH ABOVE NORMAL TEMPERATURES TO FINISH THE SHORT TERM OF THE
FORECAST. PROTON

.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...THERE HAS NOT BEEN
MUCH CHANGE IN THE THINKING AS FAR AS THE EXTENDED IS CONCERNED.
AN UPPER RIDGE BUILDS INTO THE FORECAST AREA ON SATURDAY WHICH
WILL LEAD TO MOSTLY SUNNY SKIES AND DRY CONDITIONS. SATURDAY NIGHT
UNDER MAINLY CLEAR SKIES IF WINDS BECOME LIGHT THERE COULD BE THE
POTENTIAL FOR THE FORMATION OF FREEZING FOG. THE 00Z ECMWF BRINGS
IN THE NEXT SHORTWAVE FOR SUNDAY AFTERNOON AND SO THAT SHOULD HELP
TO MIX OUT ANY FOG THAT DOES DEVELOP. THE 00Z GFS TAKES THIS WAVE
FURTHER TO THE NORTH...KEEPING THE CWA IN NORTHWEST FLOW ALOFT.
REGARDLESS...MODEL GUIDANCE IS DRY FOR THE PERIOD SO DID NOT
INSERT A MENTION OF POPS WITH THIS WAVE. THE ECMWF BRINGS YET
ANOTHER UPPER WAVE THROUGH THE AREA ON MONDAY AFTERNOON AND THE
GFS AGAIN TRACKS IT TO THE NORTH. ONCE AGAIN DO NOT EXPECT MUCH
PRECIPITATION TO RESULT.

TUESDAY AND BEYOND...TOWARDS THE MIDDLE OF THE WEEK MODELS ARE
CONVERGING ON THE IDEA OF THE WESTERN HALF OF THE U.S. BEING
DOMINATED BY SPLIT FLOW ALOFT. THIS PLACES NORTHEAST MONTANA UNDER
THE INFLUENCE OF AN UPPER RIDGE ASSOCIATED WITH THE DRIER NORTHERN
BRANCH. THUS...HAVE MODERATING TEMPERATURES IN THE GRIDS THROUGH
THE MIDDLE OF NEXT WEEK. MID 40S FOR HIGHS SEEM LIKE A REAL
POSSIBILITY IN SOME LOCATIONS IN PHILLIPS AND PETROLEUM COUNTIES
AS WELL AS PARTS OF WESTERN GARFIELD COUNTY AS THE ECMWF WARMS
850MB TEMPERATURES AS HIGH AS +8C BY TUESDAY AFTERNOON. WENT AHEAD
AND PUT IN SLIGHT CHANCE POPS ACROSS THE ENTIRE CWA FOR WEDNESDAY
INTO THURSDAY AS LONG RANGE MODELS ARE IN AGREEMENT THAT A
VIGOROUS SHORTWAVE WILL TRANSLATE ACROSS NORTHEAST MONTANA
SOMETIME DURING THIS PERIOD. NOT TOO CONFIDENT THIS FAR OUT BUT
FELT IT DID WARRENT A MENTION SINCE THERE IS DECENT MODEL
AGREEMENT. MALIAWCO


&&

.AVIATION...
A SHORTWAVE TROUGH EXITS THE REGION DURING THE DAYTIME HOURS AS A
RIDGE BUILDS IN FROM THE WEST. THIS WILL PUT AN END TO ANY
ISOLATED TO SCATTERED SNOW SHOWERS IN THE VICINITY IN THE MORNING.
ANY MVFR OR IFR CEILINGS WILL ALSO BEGIN TO LIFT AS SKIES CLEAR
THROUGHOUT THE DAY. THUS...ANTICIPATING A RETURN TO VFR BY THE
LATE MORNING OR AFTERNOON. EXPECT WEST TO NORTHWEST SURFACE WINDS
DURING THE DAY RANGING FROM 10-20 KTS. MALIAWCO

&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

WEATHER.GOV/GLASGOW






AREA FORECAST DISCUSSION

NWS GLASGOW MT

 241 AM MST WED JAN 2 2013

.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH FRIDAY...
A DIFFICULT BEGINNING TO THE FORECAST THIS MORNING ACROSS
NORTHEAST MONTANA. A FEW SNOW SHOWERS ARE FLOATING AROUND THE
SOUTHERN ZONES...BUT UPSTREAM FAIRLY CLEAR VIA THE IR SAT THIS
MORNING. BETHUNE AND SCHULER RADARS TO OUR NORTH HAVE THE SNOW
SHOWERS MAINLY EAST OF ASSININBOIA THIS MORNING TRACKING
SOUTHEAST. WILL KEEP THE HIGHER POPS ALONG THE NORTH DAKOTA BORDER
EVEN THOUGH CONFIDENCE IS FALLING OFF QUICKLY WITH THE NAM/GFS AS
PER THE HRRR WHICH KEEPS THE AREA DRY THROUGH THE MORNING HOURS.
IF THE EAST STARTS TO CLEAR MIGHT HAVE TO MAKE AN EARLY MORNING
UPDATE TO IMPROVE THE WEATHER IN THE EAST TODAY.

BY TONIGHT THE RIDGE BUILDS IN...AS PER ALL GUIDANCE PRODUCTS
WHICH WILL DRY THE AREA OUT ABOVE 2700 FEET IN THE ATMOSPHERE AND
BEGIN TO WARM IT UP AT THE HIGHER ELEVATIONS. THE LOWER ELEVATIONS
WILL STAY BELOW THE INVERSION AND IN THE SHALLOW COLD AIR WILL
LOOKS TO HANG ON UNTIL FRIDAY. MAKES FOR A DIFFICULT TEMPERATURE
FORECAST... ABOVE 3000 FEET 30S AND 40S LOOK GOOD... BELOW 2500
SORRY BUT LOOKS FOR THE TEENS AND 20S WITH OVERNIGHT LOWS IN THE
SINGLE DIGITS. ITS THE IN BETWEEN THOSE TWO ELEVATIONS THAT WILL
BOUNCE AROUND.

FRIDAY THE RIDGE GETS FLATTENED BY A DRY SHORTWAVE WHICH SHOULD
ALLOW MIXING DOWN INTO THE VALLEYS AND ALLOW THE VALLEY BOTTOM
LOCATIONS TO ENJOY A LITTLE WARMER AIR... CHINOOK WINDS SHOULD
KICK UP IN THE WESTERN ZONES AND HIGHER ELEVATIONS IN THE EAST
WITH ABOVE NORMAL TEMPERATURES TO FINISH THE SHORT TERM OF THE
FORECAST. PROTON

.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...
THERE HAS NOT BEEN MUCH CHANGE IN THE THINKING AS FAR AS THE
EXTENDED IS CONCERNED. AN UPPER RIDGE BUILDS INTO THE FORECAST
AREA ON SATURDAY WHICH WILL LEAD TO MOSTLY SUNNY SKIES AND DRY
CONDITIONS. SATURDAY NIGHT UNDER MAINLY CLEAR SKIES IF WINDS
BECOME LIGHT THERE COULD BE THE POTENTIAL FOR THE FORMATION OF
FREEZING FOG. THE 00Z ECMWF BRINGS IN THE NEXT SHORTWAVE FOR
SUNDAY AFTERNOON AND SO THAT SHOULD HELP TO MIX OUT ANY FOG THAT
DOES DEVELOP. THE 00Z GFS TAKES THIS WAVE FURTHER TO THE
NORTH...KEEPING THE CWA IN NORTHWEST FLOW ALOFT. REGARDLESS...MODEL
GUIDANCE IS DRY FOR THE PERIOD SO DID NOT INSERT A MENTION OF POPS
WITH THIS WAVE. THE ECMWF BRINGS YET ANOTHER UPPER WAVE THROUGH
THE AREA ON MONDAY AFTERNOON AND THE GFS AGAIN TRACKS IT TO THE
NORTH. ONCE AGAIN DO NOT EXPECT MUCH PRECIPITATION TO RESULT.

TUESDAY AND BEYOND...TOWARDS THE MIDDLE OF THE WEEK MODELS ARE
CONVERGING ON THE IDEA OF THE WESTERN HALF OF THE U.S. BEING
DOMINATED BY SPLIT FLOW ALOFT. THIS PLACES NORTHEAST MONTANA UNDER
THE INFLUENCE OF AN UPPER RIDGE ASSOCIATED WITH THE DRIER NORTHERN
BRANCH. THUS...HAVE MODERATING TEMPERATURES IN THE GRIDS THROUGH
THE MIDDLE OF NEXT WEEK. MID 40S FOR HIGHS SEEM LIKE A REAL
POSSIBILITY IN SOME LOCATIONS IN PHILLIPS AND PETROLEUM COUNTIES
AS WELL AS PARTS OF WESTERN GARFIELD COUNTY AS THE ECMWF WARMS
850MB TEMPERATURES AS HIGH AS +8C BY TUESDAY AFTERNOON. WENT AHEAD
AND PUT IN SLIGHT CHANCE POPS ACROSS THE ENTIRE CWA FOR WEDNESDAY
INTO THURSDAY AS LONG RANGE MODELS ARE IN AGREEMENT THAT A
VIGOROUS SHORTWAVE WILL TRANSLATE ACROSS NORTHEAST MONTANA
SOMETIME DURING THIS PERIOD. NOT TOO CONFIDENT THIS FAR OUT BUT
FELT IT DID WARRENT A MENTION SINCE THERE IS DECENT MODEL
AGREEMENT. MALIAWCO


&&

.AVIATION...
A SHORTWAVE TROUGH EXITS THE REGION DURING THE DAYTIME HOURS AS A
RIDGE BUILDS IN FROM THE WEST. THIS WILL PUT AN END TO ANY
ISOLATED TO SCATTERED SNOW SHOWERS IN THE VICINITY IN THE MORNING. ANY
MVFR OR IFR CEILINGS WILL ALSO BEGIN TO LIFT AS SKIES CLEAR
THROUGHOUT THE DAY. THUS...ANTICIPATING A RETURN TO VFR BY THE
LATE MORNING OR AFTERNOON. EXPECT WEST TO NORTHWEST SURFACE WINDS
DURING THE DAY RANGING FROM 10-20 KTS. MALIAWCO

&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

WEATHER.GOV/GLASGOW






AREA FORECAST DISCUSSION

NWS HASTINGS NE

 949 PM CST THU JAN 3 2013

.UPDATE...GOOD RADIATIONAL CONDITIONS HAVE SET UP TONIGHT AND
VSBYS ARE BEGINNING TO FALL IN OUR SOUTH/SOUTHEAST ZONES WHERE
AFTN TEMPS WERE NEAR OR JUST ABOVE FREEZING. HAVE EXPANDED AREA
FOR PATCHY FOG DEVELOPMENT AND INCLUDED POTENTIAL FOR VSBYS
BELOW ONE MILE. WILL CONTINUE TO MONITOR VSBYS/FOG TREND THRU THE
NIGHT.

&&

.PREV DISCUSSION... /ISSUED 520 PM CST THU JAN 3 2013/

AVIATION...00Z TAF. A SURFACE HIGH PRESSURE SYSTEM TO THE SOUTH
WILL KEEP WINDS FAIRLY LIGHT FROM THE SOUTHWEST THROUGH THE
PERIOD. SKIES SHOULD BE CLEAR.

PREV DISCUSSION... /ISSUED 333 PM CST THU JAN 3 2013/

SHORT TERM...THROUGH 00Z SATURDAY. MORNING UPPER AIR ANALYSIS
INDICATES A POSITIVELY TILTED LONGWAVE TOUGH EXTENDING FROM THE
GREAT LAKES REGION INTO THE SOUTHWESTERN CONUS...WITH RIDGING OVER
MUCH OF THE WESTERN CONUS AND QUASI-ZONAL FLOW ACROSS THE EAST.
MID AND UPPER LEVEL JET ENERGY EXTENDS FROM THE SOUTHERN
PLAINS...EAST/NORTHEAST INTO THE MID-ATLANTIC. TROPOSPHERIC FLOW
OVER OUR AREA IS NOT OVERLY IMPRESSIVE AS A RESULT...MAXING OUT AT
AROUND 50KTS NEAR 350MB PER 12Z RAP ANALYSIS SOUNDING DATA FOR
KGRI. WATER VAPOR IMAGERY INDICATES INCREASED VALUES OF MID LEVEL
MOISTURE OVER PORTIONS OF THE SOUTHEASTERN CONUS AHEAD OF THE MID
LEVEL TROUGH AXIS...HOWEVER MID LEVEL MOISTURE FARTHER
NORTHWEST...OVER THE CENTRAL PLAINS...REMAINS FAIRLY MEAGER. AT
THE SURFACE A RIDGE OF HIGH PRESSURE IS NOTED EXTENDING FROM NORTH
TEXAS...NORTHEAST INTO EASTERN KANSAS. AS A RESULT...THE LOW LEVEL
WIND FIELD ACROSS OUR AREA REMAINS FROM THE WEST/SOUTHWEST BUT IS
VERY LIGHT.

GUIDANCE FROM THE NAM...OPERATIONAL GFS AND EC SUGGEST THE MID
LEVEL TROUGH...CURRENTLY MOVING OVER CENTRAL PORTIONS OF THE
CONUS...WILL DEEPEN INTO A CLOSED LOW OVER THE SOUTHERN PLAINS
TONIGHT INTO TOMORROW. DESPITE THIS DEEPENING MID LEVEL LOW...ANY
OMEGA IN ASSOCIATION WITH THIS SYSTEM IS EXPECTED TO REMAIN OVER
THE SOUTHERN PLAINS...WITH DRY CONDITIONS EXPECTED OVER OUR AREA
TONIGHT AND TOMORROW.

CLEAR SKIES AND 2-6 INCHES OF SNOWPACK ACROSS OUR AREA SHOULD
PROMOTE STRONG RADIATIONAL COOLING TONIGHT...WITH 25-30 DEGREE
DROP OFFS NOT OUT OF THE QUESTION FOR MANY LOCATIONS ACROSS THE
CWA. OVERNIGHT LOWS IN THE SINGLE DIGITS ABOVE ZERO ARE FORECAST
FOR MOST LOCATIONS AS ACROSS THE AREA AS A RESULT. AN INCREASING
SOUTHWESTERLY LOW LEVEL WIND FIELD SHOULD PROMOTE SUBTLE LOW LEVEL
WARM AIR ADVECTION DURING THE DAY FRIDAY...WITH 30-35 DEGREE RISES
CURRENTLY FORECAST. THIS PRESENTS FRIDAY AFTERNOON HIGHS GENERALLY
IN THE 30S.

FINALLY...WITH STRONG RADIATIONAL COOLING EXPECTED TONIGHT AND LOW
LEVEL DEWPOINTS LINGERING IN THE SINGLE DIGITS ABOVE ZERO...NEAR-
SURFACE DEWPOINT DEPRESSIONS NEAR ZERO WILL LIKELY BE REALIZED.
ALTHOUGH DRIER LOW LEVEL AIR WILL BE ADVECTING IN FROM EASTERN
COLORADO AND WESTERN KANSAS...IT APPEARS THE STRONG RADIATIONAL
COOLING...WORKING IN CONCERT WITH A LIGHT LOW LEVEL WIND
FIELD...COULD BE CONDUCIVE FOR PATCHY FOG DEVELOPMENT. WENT AHEAD
WITH SUCH WORDING IN THE FORECAST...PRIMARILY ACROSS OUR
SOUTHEASTERN CWA WHICH IS WHERE LOW LEVEL MOISTURE IS EXPECTED TO
BE THE HIGHEST AND THE LOW LEVEL WIND FIELD IS EXPECTED TO BE THE
WEAKEST.

LONG TERM...FRIDAY NIGHT THROUGH THURSDAY. MAIN FORECAST CONCERNS
WILL BE CHANCE FOR PRECIPITATION WEDNESDAY AND WEDNESDAY NIGHT AND
TEMPERATURES THROUGH THE PERIOD.

A COLD FRONT IS EXPECTED TO MOVE THROUGH THE AREA FRIDAY NIGHT.
DESPITE THE COLD FRONT THE TEMPERATURES FRIDAY NIGHT WILL BE A FEW
DEGREES WARMER THAN THURSDAY NIGHT. THERE IS WARMER AIR ACROSS THE
REGION AND THE COLDER AIR DOES NOT MOVE INTO THE REGION UNTIL ON
SATURDAY. EVEN THIS IS NOT MUCH COLDER AND TEMPERATURES WILL BE
ABOUT THE SAME AS ON FRIDAY. IN ADDITION THERE IS A WEAK UPPER
LEVEL WAVE THAT MOVES INTO THE AREA ON SATURDAY AND BRINGS A FEW
CLOUDS TO THE REGION.

SATURDAY NIGHT INTO SUNDAY AN UPPER LEVEL RIDGE MOVES INTO THE
AREA AND WARM ADVECTION STARTS UP ACROSS THE AREA. WINDS TURN TO
THE SOUTH/SOUTHWEST AND INCREASE. ALL OF THIS SHOULD SHOW UP IN
TEMPERATURES WARMING A BIT ON SUNDAY.

MODELS START TO DIVERGE GREATLY NEXT WEEK. THE GFS AND CANADIAN
BOTH OPEN THE WAVE SOME AND MOVE IT THROUGH MONDAY AND TUESDAY.
THE ECMWF CONTINUES TO KEEP A STRONG UPPER LEVEL LOW THAT MOVES
FROM THE FOUR CORNERS REGION TO THE SOUTHERN PLAINS. THE ECMWF HAS
MAINTAINED SOME RUN TO RUN CONSISTENCY WHILE THE OTHERS HAVE MADE
SOME CHANGES IN THE LAST RUN. FOR NOW WILL CONTINUE TO HAVE THE
PRECIPITATION ON WEDNESDAY AND WEDNESDAY NIGHT WHICH IS MORE
SIMILAR TO THE ECMWF. THE NEXT QUESTION WILL BE PRECIPITATION
TYPE. IN ADDITION TO THE TIMING CHANGE THAT THE GFS
HAS...TEMPERATURES ARE MUCH COLDER...WHICH IS DIFFERENT THAN
PREVIOUS RUNS. HAVE CONTINUED THE WARMER TEMPERATURES AND
THEREFORE WILL KEEP RAIN IN THE FORECAST FOR WEDNESDAY. AS THE
TEMPERATURES COOL OFF WEDNESDAY NIGHT THERE WILL BE SOME SNOW
MIXED INTO THE RAIN. BY THURSDAY...THE UPPER LEVEL LOW HAS MOVED
OFF TO THE EAST AND THEREFORE EXPECT DRY CONDITIONS.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$








AREA FORECAST DISCUSSION

NWS HASTINGS NE

 520 PM CST THU JAN 3 2013

.AVIATION...00Z TAF. A SURFACE HIGH PRESSURE SYSTEM TO THE SOUTH
WILL KEEP WINDS FAIRLY LIGHT FROM THE SOUTHWEST THROUGH THE
PERIOD. SKIES SHOULD BE CLEAR.

&&

.PREV DISCUSSION... /ISSUED 333 PM CST THU JAN 3 2013/

SHORT TERM...THROUGH 00Z SATURDAY. MORNING UPPER AIR ANALYSIS
INDICATES A POSITIVELY TILTED LONGWAVE TOUGH EXTENDING FROM THE
GREAT LAKES REGION INTO THE SOUTHWESTERN CONUS...WITH RIDGING OVER
MUCH OF THE WESTERN CONUS AND QUASI-ZONAL FLOW ACROSS THE EAST.
MID AND UPPER LEVEL JET ENERGY EXTENDS FROM THE SOUTHERN
PLAINS...EAST/NORTHEAST INTO THE MID-ATLANTIC. TROPOSPHERIC FLOW
OVER OUR AREA IS NOT OVERLY IMPRESSIVE AS A RESULT...MAXING OUT AT
AROUND 50KTS NEAR 350MB PER 12Z RAP ANALYSIS SOUNDING DATA FOR
KGRI. WATER VAPOR IMAGERY INDICATES INCREASED VALUES OF MID LEVEL
MOISTURE OVER PORTIONS OF THE SOUTHEASTERN CONUS AHEAD OF THE MID
LEVEL TROUGH AXIS...HOWEVER MID LEVEL MOISTURE FARTHER
NORTHWEST...OVER THE CENTRAL PLAINS...REMAINS FAIRLY MEAGER. AT
THE SURFACE A RIDGE OF HIGH PRESSURE IS NOTED EXTENDING FROM NORTH
TEXAS...NORTHEAST INTO EASTERN KANSAS. AS A RESULT...THE LOW LEVEL
WIND FIELD ACROSS OUR AREA REMAINS FROM THE WEST/SOUTHWEST BUT IS
VERY LIGHT.

GUIDANCE FROM THE NAM...OPERATIONAL GFS AND EC SUGGEST THE MID
LEVEL TROUGH...CURRENTLY MOVING OVER CENTRAL PORTIONS OF THE
CONUS...WILL DEEPEN INTO A CLOSED LOW OVER THE SOUTHERN PLAINS
TONIGHT INTO TOMORROW. DESPITE THIS DEEPENING MID LEVEL LOW...ANY
OMEGA IN ASSOCIATION WITH THIS SYSTEM IS EXPECTED TO REMAIN OVER
THE SOUTHERN PLAINS...WITH DRY CONDITIONS EXPECTED OVER OUR AREA
TONIGHT AND TOMORROW.

CLEAR SKIES AND 2-6 INCHES OF SNOWPACK ACROSS OUR AREA SHOULD
PROMOTE STRONG RADIATIONAL COOLING TONIGHT...WITH 25-30 DEGREE
DROP OFFS NOT OUT OF THE QUESTION FOR MANY LOCATIONS ACROSS THE
CWA. OVERNIGHT LOWS IN THE SINGLE DIGITS ABOVE ZERO ARE FORECAST
FOR MOST LOCATIONS AS ACROSS THE AREA AS A RESULT. AN INCREASING
SOUTHWESTERLY LOW LEVEL WIND FIELD SHOULD PROMOTE SUBTLE LOW LEVEL
WARM AIR ADVECTION DURING THE DAY FRIDAY...WITH 30-35 DEGREE RISES
CURRENTLY FORECAST. THIS PRESENTS FRIDAY AFTERNOON HIGHS GENERALLY
IN THE 30S.

FINALLY...WITH STRONG RADIATIONAL COOLING EXPECTED TONIGHT AND LOW
LEVEL DEWPOINTS LINGERING IN THE SINGLE DIGITS ABOVE ZERO...NEAR-
SURFACE DEWPOINT DEPRESSIONS NEAR ZERO WILL LIKELY BE REALIZED.
ALTHOUGH DRIER LOW LEVEL AIR WILL BE ADVECTING IN FROM EASTERN
COLORADO AND WESTERN KANSAS...IT APPEARS THE STRONG RADIATIONAL
COOLING...WORKING IN CONCERT WITH A LIGHT LOW LEVEL WIND
FIELD...COULD BE CONDUCIVE FOR PATCHY FOG DEVELOPMENT. WENT AHEAD
WITH SUCH WORDING IN THE FORECAST...PRIMARILY ACROSS OUR
SOUTHEASTERN CWA WHICH IS WHERE LOW LEVEL MOISTURE IS EXPECTED TO
BE THE HIGHEST AND THE LOW LEVEL WIND FIELD IS EXPECTED TO BE THE
WEAKEST.

LONG TERM...FRIDAY NIGHT THROUGH THURSDAY. MAIN FORECAST CONCERNS
WILL BE CHANCE FOR PRECIPITATION WEDNESDAY AND WEDNESDAY NIGHT AND
TEMPERATURES THROUGH THE PERIOD.

A COLD FRONT IS EXPECTED TO MOVE THROUGH THE AREA FRIDAY NIGHT.
DESPITE THE COLD FRONT THE TEMPERATURES FRIDAY NIGHT WILL BE A FEW
DEGREES WARMER THAN THURSDAY NIGHT. THERE IS WARMER AIR ACROSS THE
REGION AND THE COLDER AIR DOES NOT MOVE INTO THE REGION UNTIL ON
SATURDAY. EVEN THIS IS NOT MUCH COLDER AND TEMPERATURES WILL BE
ABOUT THE SAME AS ON FRIDAY. IN ADDITION THERE IS A WEAK UPPER
LEVEL WAVE THAT MOVES INTO THE AREA ON SATURDAY AND BRINGS A FEW
CLOUDS TO THE REGION.

SATURDAY NIGHT INTO SUNDAY AN UPPER LEVEL RIDGE MOVES INTO THE
AREA AND WARM ADVECTION STARTS UP ACROSS THE AREA. WINDS TURN TO
THE SOUTH/SOUTHWEST AND INCREASE. ALL OF THIS SHOULD SHOW UP IN
TEMPERATURES WARMING A BIT ON SUNDAY.

MODELS START TO DIVERGE GREATLY NEXT WEEK. THE GFS AND CANADIAN
BOTH OPEN THE WAVE SOME AND MOVE IT THROUGH MONDAY AND TUESDAY.
THE ECMWF CONTINUES TO KEEP A STRONG UPPER LEVEL LOW THAT MOVES
FROM THE FOUR CORNERS REGION TO THE SOUTHERN PLAINS. THE ECMWF HAS
MAINTAINED SOME RUN TO RUN CONSISTENCY WHILE THE OTHERS HAVE MADE
SOME CHANGES IN THE LAST RUN. FOR NOW WILL CONTINUE TO HAVE THE
PRECIPITATION ON WEDNESDAY AND WEDNESDAY NIGHT WHICH IS MORE
SIMILAR TO THE ECMWF. THE NEXT QUESTION WILL BE PRECIPITATION
TYPE. IN ADDITION TO THE TIMING CHANGE THAT THE GFS
HAS...TEMPERATURES ARE MUCH COLDER...WHICH IS DIFFERENT THAN
PREVIOUS RUNS. HAVE CONTINUED THE WARMER TEMPERATURES AND
THEREFORE WILL KEEP RAIN IN THE FORECAST FOR WEDNESDAY. AS THE
TEMPERATURES COOL OFF WEDNESDAY NIGHT THERE WILL BE SOME SNOW
MIXED INTO THE RAIN. BY THURSDAY...THE UPPER LEVEL LOW HAS MOVED
OFF TO THE EAST AND THEREFORE EXPECT DRY CONDITIONS.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$








AREA FORECAST DISCUSSION

NWS WILMINGTON NC

 643 AM EST WED JAN 2 2013

.SYNOPSIS...
A COLD FRONT MOVING THROUGH LATE TODAY WILL USHER IN SOME DRIER
AIR SHUTTING OFF THE RAIN ALTHOUGH CLOUDS WILL TEND TO LINGER. A
WAVE OF LOW PRESSURE ALONG THE FRONT AS IT SITS OFF THE COAST WILL
FINALLY ALLOW SOME CLEARING THURSDAY NIGHT. HIGH PRESSURE WILL
BUILD IN FROM THE WEST OVER THE WEEKEND FOLLOWED BY A RAIN-FREE
COLD FRONT ON SUNDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM WEDNESDAY...THE FRONT APPEARS TO BE DROPPING SOUTH A
LITTLE FASTER THAN EARLIER MODELS INDICATED. THE RUC HAS THE BEST
NEAR-TERM INITIALIZATION AND IS THE BASIS FOR UPDATES OVER THE NEXT
8 HOURS. WINDS HAVE SHIFTED TO THE NORTH AT WILMINGTON...
WHITEVILLE...GREEN SEA...MARION AND FLORENCE. THE WIND SHIFT SHOULD
REACH THE MYRTLE BEACH AREA VERY SOON...AND GEORGETOWN BY 9-10 AM. A
NARROW RIBBON OF WARM AIR ALONG THE SC COAST (STILL 61 IN GEORGETOWN
AND 63 IN MYRTLE BEACH) WILL BE SWEPT OUT TO SEA BY THE FRONT WITH
FALLING TEMPERATURES EXPECTED LATER THIS MORNING. FOR AREAS WHERE
THE FRONT HAS ALREADY PASSED...TEMPERATURES SHOULD CONTINUE FOR THE
NEXT FEW HOURS AS COOL AIR BLEEDS IN FROM THE NORTH. ONCE
PRECIPITATION ENDS TEMPERATURE CURVES WILL TURN UPWARDS SLIGHTLY
DURING THE MID AFTERNOON BUT EVEN THEN WE ARE ONLY TALKING A FEW
DEGREES RISE WITH CONSIDERABLE CLOUD COVER REMAINING.

ONE LAST BATCH OF LIGHT RAIN OVER CENTRAL SOUTH CAROLINA SHOULD NOT
INTENSIFY AS IT STREAKS EAST TO THE COAST OVER THE NEXT 3-4 HOURS.
BEHIND IT...CLOUDS WILL REMAIN BUT THE IMPETUS FOR ADDITIONAL PRECIP
APPEARS MISSING WITH THE SUBTROPICAL JET STREAK MOVING OFF THE
NORTHEAST U.S. COAST. PREVIOUS DISCUSSION FROM 300 AM FOLLOWS...

A WEAK AREA OF LOW PRESSURE IS CROSSING THE EASTERN CAROLINAS...
FOLLOWING A SLOW MOVING COLD FRONT THAT IS DROPPING SOUTHWARD TOWARD
THE COAST. THIS FRONT IS BECOMING A LITTLE EASIER TO FIND IN SURFACE
OBSERVATIONS...OUTLINED BY A SHIFT TO NORTH WINDS ACROSS CENTRAL
NORTH CAROLINA INTO NORTHWESTERN SOUTH CAROLINA. A BROAD STRIPE OF
LIGHT TO MODERATE RAINFALL NEAR AND NORTH OF THE FRONT IS BEING
PRODUCED MAINLY THROUGH JET DYNAMICS AS THE CAROLINAS ARE WITHIN THE
RIGHT-ENTRANCE REGION OF A STRONG JET STREAK ACROSS THE NORTHEASTERN
STATES. AS THIS JET STREAK PUSHES FARTHER OFFSHORE AFTER DAYBREAK
THE RAIN HERE IN THE CAROLINAS SHOULD GRADUALLY DIMINISH IN
INTENSITY AND COVERAGE.

HIGH TEMPERATURES TODAY ARE GOING TO BE A TOUGH CALL PARTICULARLY
ALONG THE SOUTH CAROLINA COAST AS THE FRONT MAY STILL BE TO THE
NORTH AT 12Z/7 AM EST. A WARM SOUTHWEST WIND AHEAD OF THE FRONT MAY
KEEP GEORGETOWN IN THE LOWER 60S UP UNTIL THE FRONT ARRIVES...WITH
UPPER 50S POSSIBLE IN MYRTLE BEACH. BEHIND THE FRONT TEMPERATURES
SHOULD FALL INTO THE LOWER TO MID 50S ALONG THE SC COAST WITH LITTLE
CHANGE REST OF THE DAY. FARTHER NORTH TODAY`S HIGH TEMPERATURE
FORECAST IS A LITTLE MORE CERTAIN WITH A NEARLY STEADY 53-55
EXPECTED FOR MOST AREAS. SKIES SHOULD REMAIN OVERCAST MUCH OF THE
DAY.

THE FRONT WILL STALL ACROSS NORTH FLORIDA AND THE GEORGIA OFFSHORE
WATERS TONIGHT. LOW PRESSURE WILL DEVELOP ALONG THIS FRONT LATE
TONIGHT WHICH MAY LEAD TO RENEWED DEVELOPMENT OF LIGHT RAIN MAINLY
ALONG THE COAST. WITH CONTINUED LOW-LEVEL COLD ADVECTION LOWS
TONIGHT SHOULD FALL TO THE UPPER 30S OVER INTERIOR SOUTHEASTERN
NORTH CAROLINA TO THE LOWER 40S ELSEWHERE.

&&

.SHORT TERM/THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...A BROAD SWATH OF WEST-SOUTHWESTERLY MID LEVEL
FLOW WILL BE STREAMING ACROSS THE SOUTHEAST ON THURSDAY. EMBEDDED
WITHIN THIS FLOW WILL BE A WEAK SHORTWAVE THAT WILL SPIN UP A SMALL
AREA OF LOW PRESSURE ALONG THE WELL-OFFSHORE FRONTAL BOUNDARY. THIS
COULD SPREAD SOME VERY LIGHT RAINFALL ALONG THE IMMEDIATE COAST
WHEREAS AREAS FURTHER INLAND WILL SEE PLENTY OF CLOUDS BUT TEND TO
STAY RAIN FREE. IN THE WAKE OF THIS SYSTEM SOME DRY AIR WILL MANAGE
TO PUSH IN FROM THE NORTHWEST THURSDAY NIGHT BRINGING CLEARING
SKIES. IT WILL ALSO BRING SOME LOW LEVEL COLD AIR ADVECTION KEEPING
FRIDAY AFTERNOON A FEW DEGREES ON THE CHILLY SIDE OF NORMAL DESPITE
THE RETURN OF SUNSHINE. HIGH PRESSURE REMAINING TO OUR WEST FRIDAY
NIGHT WILL MAINTAIN A FEW MPH OF NORTHERLY WINDS AND PREVENT IDEAL
RADIATIONAL COOLING OTHERWISE SUPPORTED BY THE MINIMAL CLOUD COVER.
THERE WILL ALSO BE SOME WARM ADVECTION JUST GETTING UNDERWAY OVER
SOUTHERN ZONES THE LAST FEW HOURS OF THE PERIOD.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...WEAKENING HIGH PRESSURE MOVES ACROSS THE AREA
OVER THE WEEKEND KEEPING CLOUD COVER FAIRLY MINIMAL AND TEMPERATURES
FAIRLY CLOSE TO SEASONABLE NORMS. SUNDAY INTO MONDAY WILL SEE AN
UPPER TROUGH SHARPENING ACROSS THE GREAT LAKES DRIVING A COLD FRONT
SOUTH AND EAST. MOISTURE FLUX AHEAD OF THIS BOUNDARY WILL BE NEARLY
NIL SO ITS ABILITY TO PRODUCE RAINFALL IN THE EAST JUST ABOUT THE
SAME. THIS BOUNDARY WILL MOVE TROUGH LATER SUNDAY. MONDAY WILL SEE
HIGH PRESSURE MOVE IN FROM THE NW. TOUGH CALL ON TEMPS MONDAY AS THE
THERMAL TROUGH BEHIND THE COLD FRONT IS SO NARROW THAT WARM
ADVECTION BACK UNDERWAY BY AFTERNOON. IT MAY END UP BEING QUITE
SEASONABLE. THIS WAA SHOULD THEN TRANSLATE TO A MILDER TUESDAY.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 12Z...MVFR/IFR DUE TO LOWERED CIGS AND VISIBILITIES ARE
SPREADING ACROSS THE ENTIRE AREA THIS MORNING AS A FRONT
SITUATED JUST INLAND FROM THE COAST CONTINUES TO SLOWLY PUSH ITS WAY
TOWARDS THE COAST. CURRENT RADAR IMAGERY DEPICTS A FEW LIGHT SHOWERS
ACROSS THE FA WHICH WILL TAPER OFF WITHIN THE NEXT HOUR OR
TWO...LEAVING BEHIND MVFR/IFR DUE TO LOWERED CIGS THROUGH LATE
MORNING. LIGHT NORTH WINDS THIS MORNING WILL INCREASE TO AOB 8 KTS
BY THIS AFTERNOON.

MODELS ARE IN A BIT OF A DISAGREEMENT AS TO WHEN THESE
CIGS WILL LIFT TO VFR...BUT GIVEN TIME-HEIGHT ANALYSIS AND FCST
SOUNDINGS HAVE INTRODUCED VFR FOR THIS AFTERNOON WITH SCT/BKN MID TO
HIGH-LEVEL CLOUDS. OVERNIGHT AND INTO THE MORNING HOURS...THE RETURN
OF LOW CLOUDS MAY CREATE SUB-VFR CONDITIONS ONCE AGAIN...BUT GIVEN
LOWERED CONFIDENCE ATTM...HAVE NOT INTRODUCED ANY RESTRICTIONS AS OF
YET. NORTH-NORTHEAST WINDS WILL CONTINUE THROUGH THE PERIOD WITH
SUSTAINED WINDS AOB 8 KTS.

EXTENDED OUTLOOK...CHANCE FOR RAIN AND PERIODS OF SUB-VFR CONDITIONS
THROUGH LATE THURSDAY ASSOCIATED WITH A NEARLY STATIONARY FRONT. VFR
WILL DEVELOP FRIDAY AND PERSIST THROUGH THE REMAINDER OF THE
PERIOD.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM WEDNESDAY...THE FRONT IS COMING THROUGH JUST A BIT
FASTER THAN EARLIER THOUGHT...ESPECIALLY INLAND WHERE WINDS HAVE
ALREADY TURNED NORTH AS FAR DOWN AS FLORENCE. AT THE BEACHES THE
FRONT IS JUST NOW PASSING MASONBORO ISLAND. THE RUC MODEL APPEARS TO
HAVE THE BEST HANDLE ON CURRENT CONDITIONS AND IS THE BASIS FOR WIND
AND WEATHER UPDATES OVER THE NEXT 6-8 HOURS. WINDS ARE STILL
EXPECTED TO INCREASE TO 15-20 KNOTS LATER THIS MORNING ACROSS THE NC
WATERS...WITH THIS SURGE MAKING IT INTO THE SC COASTAL WATERS AROUND
OR SHORTLY AFTER NOON. WE SHOULD REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA TODAY FOR WINDS AND SEAS. PREVIOUS DISCUSSION FROM 300 AM
FOLLOWS...

A COLD FRONT IS MAKING ITS WAY SOUTH ACROSS EASTERN NORTH CAROLINA
AND SHOULD CROSS OUR AREA LATER THIS MORNING. BASED ON SURFACE
OBSERVATIONS AND MODEL DATA THE FRONT SHOULD PASS CAPE FEAR BY 8
AM...MYRTLE BEACH BY 10 AM...AND GEORGETOWN BEFORE NOON. RAIN MAY
ACCOMPANY THE FRONT...ESPECIALLY ACROSS THE NC WATERS. CONDITIONS
SHOULD DRY OUT THIS AFTERNOON AS NORTHERLY WINDS SURGE ACROSS THE
AREA BEHIND THE FRONT. THE FRONT WILL STALL ACROSS NORTHERN FLORIDA
AND THE GEORGIA OFFSHORE WATERS TONIGHT AS LOW PRESSURE DEVELOPS
ALONG IT. THIS DEVELOPMENT COULD SPREAD SOME RAIN BACK INTO THE AREA
AFTER MIDNIGHT.

SHORT TERM/THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...NE WINDS TO START WITH A WEAK HIGH TO OUR N
WILL BACK/CHANGE IN A COUNTERCLOCKWISE FASHION AS THE DAY WEARS ON
AS A FAIRLY FLAT LOW MOVES BY WELL OFFSHORE. LOCAL SWAN BUILDS SEAS
WITH ITS PASSAGE...TO THE TUNE OF 4 FT ALONG THE 20NM BORDER. AS IT
PULLS AWAY THURSDAY NIGHT A BROAD HIGH WILL BUILD ACROSS MUCH OF THE
SOUTHERN U.S. CENTERED OVER TX. MODERATE NORTHERLY WINDS WILL HELP
TO PUSH HIGHER SEAS OUT OF THE FCST ZONES EVEN AS OVERALL WAVE
HEIGHTS DIMINISH SLOWLY ANYWAY. WAVE SHADOWING ALSO KEEPING NEAR
SHORE WAVES FAIRLY SMALL. WIND REMAINS OUT OF THE N OR NW FOR THE
REST OF THE PERIOD AS THE HIGH DRAWS A LITTLE CLOSER. THE APPROACH
OF THE HIGH WILL ALSO EASE THE GRADIENT AND WIND SPEED WILL DROP A
FEW KNOTS. THE EFFECT ON SEAS WILL BE SMALL...PERHAPS CHANGING A 2
TO 3 FT FORECAST TO 2 FT.

LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...HIGH PRESSURE BUILDS IN FROM THE WEST ON
SATURDAY BUT IN A WEAKENING STATE. WINDS THROUGH THE DAY WILL BE
VERY LIGHT AND MAY SHOW CONSIDERABLE VARIABILITY IN DIRECTION. LATE
IN THE DAY OR AT NIGHT A PREDOMINANTLY WESTERN WIND WILL DEVELOP AS
ANOTHER HIGH CENTER SETTLES OVER THE SOUTHERN U.S. A RAIN-FREE COLD
FRONT MOVES IN FROM THE NORTHWEST ON SUNDAY BOLSTERING WIND SPEEDS
ABOUT A CATEGORY INTO THE 10 TO 15 KT RANGE. SEAS SHOULD BUILD BACK
INTO THE 2 TO 3 FT RANGE FROM THE QUIETER 2 FT FORECAST SEEN
SATURDAY ACROSS MOST ZONES.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...MBB
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...SGL






AREA FORECAST DISCUSSION

NWS CHARLESTON WV

 645 PM EST THU JAN 3 2013

.SYNOPSIS...
WEAK CLIPPER LIKE SYSTEM PASSES TONIGHT. TWO UPPER LEVEL TROUGHS
PASS THIS WEEKEND. HIGH PRESSURE THEN BUILDS IN...AND DOMINATES
FOR MUCH OF THE NEW WORK WEEK.

&&

.NEAR TERM /THROUGH FRIDAY/...
UPDATE...
MODELS HAVING A DIFFICULT TIME WITH A BATCH OF LOW LEVEL MOISTURE
WORKING THROUGH THE WESTERN AND NORTHERN ZONES TONIGHT.
DIFFERENCES ARISE IN THE PERCENT SATURATION...AND WHETHER OR NOT
THIS WILL LEAD TO A CLOUD DECK...AND THE CEILING THAT DECK WOULD
CREATE. RAP AND SREF ARE MOST AGGRESSIVE...WHILE THE NAM IS LESS
SO. BELIEVE SOME CLOUDS POSSIBLE OVER THE NEXT FEW HOURS...BUT
CLEAR QUICKLY AFTER 06Z...WITH CLOUDS LINGERING IN THE MOUNTAINS
INTO FRIDAY.

PREVIOUS DISCUSSION...
WILL WATCH FOR A FAST MOVING CLIPPER TYPE FRONT CROSSING TONIGHT.
MOISTURE SEEMS LIMITED AND RATHER SHALLOW...ONLY EXTENDING UP TO
PERHAPS -8C. TRIMMED BACK POPS ACROSS SE OH AND N WV...LEAVING A
SCHC FLURRY MENTION IN N LOWLANDS WITH SCHC POPS ACROSS THE MTNS.
THINKING OROGRAPHIC EFFECT MAY SQUEEZE SOMETHING OUT. S EXTENT OF
CLDS ASSOCIATED WITH THIS OVERNIGHT IN QUESTIONS...WITH NAM
KEEPING MUCH OF THE LOW CLDS ACROSS SE OH AND N WV. WILL HEDGE
TOWARD CONSENSUS ALLOWING IT TO I64 CORRIDOR. WILL KEEP A STIR IN
BL WINDS OVERNIGHT AND THIS COMBINED WITH CLDS...WILL GENERALLY
LEAN ABV GUIDANCE. ANY LOW CLDS SHOULD SCT OUT BY LATE
MORNING...PERHAPS REFORMING INTO SOME STRATOCU ACROSS SE OH. BL
WINDS PICK UP QUITE A BIT IN ENSUING CAA WITH H85 WINDS TOPPING
OUT ARND 40 KTS TOMORROW. HAVE SOME 35 KT GUSTS ACROSS HIGHEST
RIDGES IN N MTNS DURING PRIME MIXING HRS WITH SOME 20 TO 25 KT
GUSTS ACROSS SE OH AND N WV. INHERITED MAXT GRID LOOKED GOOD AND
ONLY NEEDED SOME TWEAKS HERE AND THERE.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
VERY PROGRESSIVE PATTERN CONTINUES THIS PERIOD. MODELS ARE IN
GENERAL AGREEMENT ON KEEPING SOUTHERN STREAM BAROCLINIC ZONE AND
MOST OF THE PRECIP SOUTH OF OUR AREA THIS WEEKEND...IN SPITE OF A
SOUTHERN STREAM SHORT WAVE LIFTING ACROSS OUR AREA SATURDAY NIGHT.
WILL PUT LOW POPS SOUTH SATURDAY NIGHT FOR THIS FEATURE. MODELS DO
HAVE A RATHER MOISTURE STARVED SHORT WAVE AND COLD FRONT IN THE
NORTHERN STREAM DROPPING RAPIDLY SOUTHEAST ACROSS THE OHIO VALLEY
SUNDAY. MODERATE COLD ADVECTION IN NORTHWEST FLOW BEHIND THE FRONT
PROMPTS LOW POPS FOR SNOW SHOWERS...ESPECIALLY IN THE NORTHERN
MOUNTAINS...WITH LITTLE IF ANY ACCUMULATIONS. IN SUMMARY...
TEMPERATURES WILL REMAIN AT OR BELOW NORMAL...PRECIP TYPE WILL BE A
MIX IN THE LOW LANDS AND SNOW IN THE MOUNTAINS...AND PRECIP AMOUNTS
VERY MUCH ON THE LIGHT SIDE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
A STRONG SHORT WAVE WILL MOVE ACROSS THE AREA INTO SUNDAY. BUFKIT
SOUNDING CONTINUE TO INDICATE SATURATED SFC REACHING BELOW MINUS
10C LEVEL...AND AT SOME SITES BEYOND THIS LEVEL. THIS SUGGESTS GOOD
CHANCES FOR LIGHT SNOW FOLLOWED BY FREEZING DRIZZLE AS THE SYSTEM
PULLS NORTHEAST SUNDAY EVENING. NORTHWEST BACKWARDS TRAJECTORIES FROM
SUNDAY RETURNS FROM IL AND WI...BRINGING MUCH COLD AIR...CAPABLE
TO SQUEEZE LOW LEVEL MOISTURE INTO THE MOUNTAINS...TO PRODUCE
LIGHT UPSLOPE SNOW...AND ENDING WITH FREEZING DRIZZLE PER
SHALLOWER MOISTURE IN THE COLUMN WITH NO LAKE CONNECTION BELOW
MINUS 10C. THEREFORE...KEPT POPS TO CHANCE FOR NOW ACROSS THE
NORTHERN HALF OF OUR CWA THROUGH SATURDAY NIGHT DIMINISHING BY
EARLY MONDAY.

TWEAKED HPC GUIDANCE FOR TEMPS THROUGH THE PERIOD...ACCOUNTING FOR
CLOUD COVER AND GFS H850 COLDER TEMPERATURES. THE EXCEPTION WAS
MADE ON DAY 5 NIGHT...WHERE HAVE HIGH CONFIDENCE GUIDANCE IS TOO
LOW FOR MINIMUM TEMPERATURES FOR TUESDAY NIGHT...WITH GFS SHOWING
STRONG H850 SOUTHEAST FLOW AND H850 TEMPS IN ABOUT 9C...WHILE THE ECMWF
SHOWS 6C DEGREES BUT LOOKS WAY SLOWER WITH THE SFC LOW OF ABOUT 48
HOURS APART BRINGING THE 11C AT H850 UNDER STRONG SOUTHERLY FLOW.
SO...DECIDED TO GO CLOSER TO THE GFS SOLUTION AND WENT WARMER THAN
GUIDANCE.

&&

.AVIATION /23Z THURSDAY THROUGH TUESDAY/...
RELATIVE UNCERTAINTY EXISTS IN THE POTENTIAL FOR A LOW LEVEL CLOUD
DECK TONIGHT...NOT ONLY IN THE ACTUAL MATERIALIZATION OF THIS
LAYER OF MOISTURE...BUT THE CEILING IT WILL PRODUCE AS WELL. RAP
AND SREF ARE THE MOST AGGRESSIVE AS MENTIONED ABOVE. WILL CONFINE
ANY POTENTIAL MVFR CEILINGS TONIGHT TO THE NORTHERN TERMINALS AT
PKB/CKB/EKN. ELSEWHERE...KEEP THE DECK ABOVE 3KFT. A FEW FLURRIES
POSSIBLE IN THESE LOCATIONS AS WELL...WITH LOW END POPS IN THE
MOUNTAINS. WRFA5K MODEL ONLY ONE OF THE LOCAL HIRES MODELS TO
DEPICT QPF OVER THE FAR NORTHERN ZONES.

SURFACE FLOW TO INCREASE OUT OF THE WEST SOUTHWEST FRIDAY WITH
GUSTS TO AROUND 20KTS IN THE AFTERNOON WITH MIXING.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z SATURDAY...

FORECAST CONFIDENCE: MEDIUM.

ALTERNATE SCENARIOS: STRATOCUMULUS MAY BE MORE OR LESS PREVALENT
THAN FORECAST TONIGHT.

EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH:   TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW:    TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.

DATE                                                                 FRI
UTC 1HRLY       00   01   02   03   04   05   06   07   08   09   10   11
EST 1HRLY       19   20   21   22   23   00   01   02   03   04   05   06
CRW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
HTS CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
EKN CONSISTENCY  H    H    H    M    M    L    L    L    L    L    L    L
PKB CONSISTENCY  M    M    M    H    H    H    L    L    L    L    L    L
CKB CONSISTENCY  H    H    H    M    H    H    L    L    L    L    L    L

AFTER 00Z SATURDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.

&&

$$
SYNOPSIS...ARJ/JMV/30/26
NEAR TERM...30
SHORT TERM...JMV
LONG TERM...ARJ
AVIATION...26









AREA FORECAST DISCUSSION

NWS CHARLESTON WV

 152 PM EST WED JAN 2 2013

.SYNOPSIS...
HIGH PRESSURE CROSSES TONIGHT. CLIPPER LIKE SYSTEM PASSES
THURSDAY NIGHT. TWO UPPER SHORT WAVES PASS THIS WEEKEND...FOLLOWED
BY HIGH PRESSURE.

&&

.NEAR TERM /THROUGH THURSDAY/...
HEATING HAS ALLOWED STRATOCU TO FORM THIS AFTN...MOST PREVALENT
ACROSS SE OH AND N WV. LINGERING LLVL MOISTURE UNDER INVERSION
PROVIDING FOR A DREARY DAY ACROSS SW VA WITH LOW CIGS AND SOME
FOG. WILL ALLOW STRATOCU TO DISSIPATE WITH LOSS OF SUN AS CIRRUS
BLOW-OFF RIDING JET FROM SW INVADES TONIGHT. SOME CONCERN WITH LOW
STRATUS HANGING TOUGH ACROSS SE OH AND N WV PER RUC SOUNDINGS BUT
OTHER MDLS NOT REALLY SHOWING THIS. FOR TEMPS WILL HEDGE THAT
CIRRUS IS OPAQUE ENOUGH TO NOT HINDER FALL TOO MUCH. LOOKING AT
TEENS AND LWR 20S FOR MOST PART FOR OVERNIGHT LOWS.

DRY CONDITIONS PREVAIL TOMORROW WITH A MAINLY SUNNY SKY...SAVE
FOR PERHAPS PORTIONS OF SW VA TOWARD DICKENSON CO WHERE LOW CLOUDS
MAY LINGER THROUGH THE MORNING. HIGHS REBOUND SOME WITH EVERYONE
OUTSIDE OF HIGHER ELEVATIONS IN THE 30S. SOME CLDS MAY SNEAK INTO
SE OH TOWARD EVENING FROM AN APPROACHING CLIPPER TYPE FRONT.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
VERY PROGRESSIVE AND DRY PATTERN THIS PERIOD. MODELS HAVE A MOISTURE
STARVED SHORT WAVE AND COLD FRONT IN THE NORTHERN STREAM DROPPING
RAPIDLY SOUTHEAST ACROSS THE OHIO VALLEY THURSDAY NIGHT AND EARLY
FRIDAY. A THERMAL TROUGH IN NORTHWEST FLOW BEHIND THE FRONT PROMPTS
SMALL POPS FOR SNOW SHOWERS MAINLY THURSDAY NIGHT...AND MOSTLY IN
THE MOUNTAINS...WITH LITTLE IF ANY ACCUMULATIONS. THEN...A QUIET
PERIOD WITH MODERATING TEMPERATURES LATER FRIDAY AND SATURDAY AS A
LOW AMPLITUDE UPPER RIDGE BUILDS OVER THE AREA. IT WILL BE JUST
AFTER THIS PERIOD BEFORE THE NEXT SYSTEM CAN AFFECT US. LOOK FOR
BELOW NORMAL TEMPS THURSDAY NIGHT AND FRIDAY BEHIND THE
FRONT...MODERATING CLOSE TO NORMAL ON SATURDAY.

&&

.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
STRONG SHORT WAVE WILL MOVE ACROSS THE AREA SATURDAY NIGHT INTO
SUNDAY. BUFKIT SOUNDING CONTINUE TO INDICATE SATURATED SFC TO BARELY
BELOW MINUS 10C LEVEL...SUGGESTING GOOD CHANCES FOR LIGHT SNOW
FOLLOWED BY FREEZING DRIZZLE AS THE SYSTEM PULLS NORTHEAST.
NORTHWEST BACKWARDS TRAJECTORIES FROM SUNDAY RETURNS FROM IL AND
WI...BRINGING MUCH COLD AIR...CAPABLE TO SQUEEZE LOW LEVEL MOISTURE
INTO THE MOUNTAINS...TO PRODUCE LIGHT UPSLOPE SNOW OR FREEZING
DRIZZLE PER SHALLOWER MOISTURE IN THE COLUMN WITH NO LAKE CONNECTION
BELOW MINUS 10C. THEREFORE...KEPT POPS TO CHANCE FOR NOW ACROSS THE
NORTHERN HALF OF OUR CWA THROUGH SATURDAY NIGHT DIMINISHING BY EARLY
MONDAY.

TWEAKED HPC GUIDANCE FOR TEMPS THROUGH THE PERIOD...ACCOUNTING FOR
CLOUD COVER AND GFS H850 COLDER TEMPERATURES.

&&

.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
HAVE SOME TEMPO GROUPS FOR BKN MVFR ACROSS N TAF SITES THROUGH
REMAINDER OF AFTN AND ALSO KBKW. WILL ALLOW THIS TO SCT OUT WITH
LOSS OF SUN. THERE IS SOME CONCERN SCT TO BKN STRATOCU MAY LINGER
N WV AND SE OH TONIGHT. OTHERWISE...HIGH PRESSURE WILL BRING ABOUT A MAINLY
VFR NT TONIGHT...WITH CIRRUS WORKING THROUGH. AND THERE WILL ALSO
BE CIRRUS ACROSS THE AREA.

VFR CONDITIONS PREVAIL TOMORROW WITH LITTLE IN WAY OF CLDS...SAVE
FOR SOME LATE MVFR CIGS ACROSS SE OH WITH APPROACHING CLIPPER TYPE
FRONT...PROBABLY JUST BEYOND TAF PERIOD.

LIGHT NW FLOW SURFACE AND ALOFT TODAY WILL BECOME LIGHT AND
VARIABLE SURFACE AND LIGHT W ALOFT TONIGHT...INCREASING INTO 5 TO
10 KT RANGE TOMORROW AFTN.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z THURSDAY...

FORECAST CONFIDENCE: MEDIUM.

ALTERNATE SCENARIOS: STRATOCU MAY LINGER ACROSS SE OH/N WV
TONIGHT.

EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH:   TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW:    TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.

UTC 1HRLY       18   19   20   21   22   23   00   01   02   03   04   05
EST 1HRLY       13   14   15   16   17   18   19   20   21   22   23   00
CRW CONSISTENCY  H    H    H    H    H    H    H    M    M    M    M    M
HTS CONSISTENCY  H    H    H    H    H    H    H    M    M    M    M    M
BKW CONSISTENCY  M    H    H    H    H    H    H    M    M    M    M    M
EKN CONSISTENCY  H    H    H    H    H    H    H    M    M    M    M    M
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
CKB CONSISTENCY  M    M    H    H    H    H    H    M    M    M    M    M

AFTER 18Z THURSDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.

&&

$$
SYNOPSIS...ARJ/JMV/30
NEAR TERM...30
SHORT TERM...JMV
LONG TERM...ARJ
AVIATION...30











AREA FORECAST DISCUSSION

NWS CHARLESTON WV

 116 PM EST WED JAN 2 2013

.SYNOPSIS...
HIGH PRESSURE CROSSES TONIGHT. CLIPPER LIKE SYSTEM PASSES
THURSDAY NIGHT. TWO UPPER SHORT WAVES PASS THIS WEEKEND...FOLLOWED
BY HIGH PRESSURE.

&&

.NEAR TERM /THROUGH THURSDAY/...
HEATING HAS ALLOWED STRATOCU TO FORM THIS AFTN...MOST PREVALENT
ACROSS SE OH AND N WV. LINGERING LLVL MOISTURE UNDER INVERSION
PROVIDING FOR A DREARY DAY ACROSS SW VA WITH LOW CIGS AND SOME
FOG. WILL ALLOW STRATOCU TO DISSIPATE WITH LOSS OF SUN AS CIRRUS
BLOW-OFF RIDING JET FROM SW INVADES TONIGHT. SOME CONCERN WITH LOW
STRATUS HANGING TOUGH ACROSS SE OH AND N WV PER RUC SOUNDINGS BUT
OTHER MDLS NOT REALLY SHOWING THIS. FOR TEMPS WILL HEDGE THAT
CIRRUS IS OPAQUE ENOUGH TO NOT HINDER FALL TOO MUCH. LOOKING AT
TEENS AND LWR 20S FOR MOST PART FOR OVERNIGHT LOWS.

DRY CONDITIONS PREVAIL TOMORROW WITH A MAINLY SUNNY SKY...SAVE
FOR PERHAPS PORTIONS OF SW VA TOWARD DICKENSON CO WHERE LOW CLOUDS
MAY LINGER THROUGH THE MORNING. HIGHS REBOUND SOME WITH EVERYONE
OUTSIDE OF HIGHER ELEVATIONS IN THE 30S. SOME CLDS MAY SNEAK INTO
SE OH TOWARD EVENING FROM AN APPROACHING CLIPPER TYPE FRONT.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
OVERALL RELATIVELY TRANQUIL WEATHER IN THE SHORT TERM PERIOD. HIGH
PRESSURE IN CONTROL FOR START OF SHORT TERM...WITH DRY
CONDITIONS...AND SLIGHTLY WARMER TEMPERATURES AS COMPARED TO
WEDNESDAY DUE TO INCREASED SOUTHERLY FLOW. CLOUDS WILL INCREASE
THROUGHOUT THE DAY HOWEVER...AS A DISTURBANCE/CLIPPER TYPE SYSTEM
APPROACHES THE REGION FROM THE NORTH. HAVE CONTINUED TO MAINTAIN A
SLIGHT CHANCE OR CHANCE OF PRECIPITATION/IN THE FORM OF SNOW SHOWERS
IN THE FORECAST FOR THURSDAY NIGHT/FRIDAY...BUT WITH AN OVERALL LACK
OF SIGNIFICANT DEEP MOISTURE...PRECIPITATION WILL BE LIGHT...WITH
BEST CHANCES OVER NORTHERN ZONES AND NORTHERN MOUNTAIN ZONES IN THE
POST UPSLOPE FLOW. DID ELECT TO RAISE FRIDAY MORNING LOW TEMPS
SLIGHTLY FROM PREVIOUS FORECAST DUE TO EXPECTED CLOUD COVER AND WIND
ASSOCIATED WITH PASSAGE OF UPPER TROUGH. OTHERWISE...NO MAJOR
CHANGES TO PREVIOUS FORECAST.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
MODELS ARE IN FAIRLY AGREEMENT ON THE LONG TERM FORECAST WITH DRIER
PARCEL TRAJECTORIES APPROACHES FROM THE CENTRAL PLAINS...TO
PROVIDE DRY CONDITIONS INTO SATURDAY. DESPITE DRY
CONDITIONS...ABUNDANT CLOUDINESS WILL REMAIN FROM A SOUTHERN
STREAM UPPER TROUGH SATURDAY.

THE SECOND...BUT STRONGER SHORT WAVE OUT OF PHASE WITH THE
AFOREMENTIONED ONE WILL MOVE ACROSS THE AREA SATURDAY NIGHT INTO
SUNDAY. BUFKIT SOUNDING CONTINUE TO INDICATE SATURATED SFC TO
BARELY BELOW MINUS 10C LEVEL...SUGGESTING GOOD CHANCES FOR LIGHT
SNOW FOLLOWED BY FREEZING DRIZZLE AS THE SYSTEM PULLS NORTHEAST.
NORTHWEST BACKWARDS TRAJECTORIES FROM SUNDAY RETURNS FROM IL AND
WI...BRINGING MUCH COLD AIR...CAPABLE TO SQUEEZE LOW LEVEL
MOISTURE INTO THE MOUNTAINS...TO PRODUCE LIGHT UPSLOPE SNOW OR
FREEZING DRIZZLE PER SHALLOWER MOISTURE IN THE COLUMN WITH NO LAKE
CONNECTION BELOW MINUS 10C. THEREFORE...KEPT POPS TO CHANCE FOR
NOW ACROSS THE NORTHERN HALF OF OUR CWA THROUGH SATURDAY NIGHT
DIMINISHING BY EARLY MONDAY.

TWEAKED HPC GUIDANCE FOR TEMPS THROUGH THE PERIOD...ACCOUNTING FOR
CLOUD COVER AND GFS H850 COLDER TEMPERATURES.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
HAVE SOME TEMPO GROUPS FOR BKN MVFR ACROSS N TAF SITES THROUGH
REMAINDER OF AFTN AND ALSO KBKW. WILL ALLOW THIS TO SCT OUT WITH
LOSS OF SUN. THERE IS SOME CONCERN SCT TO BKN STRATOCU MAY LINGER
N WV AND SE OH TONIGHT. OTHERWISE...HIGH PRESSURE WILL BRING ABOUT A MAINLY
VFR NT TONIGHT...WITH CIRRUS WORKING THROUGH. AND THERE WILL ALSO
BE CIRRUS ACROSS THE AREA.

VFR CONDITIONS PREVAIL TOMORROW WITH LITTLE IN WAY OF CLDS...SAVE
FOR SOME LATE MVFR CIGS ACROSS SE OH WITH APPROACHING CLIPPER TYPE
FRONT...PROBABLY JUST BEYOND TAF PERIOD.

LIGHT NW FLOW SURFACE AND ALOFT TODAY WILL BECOME LIGHT AND
VARIABLE SURFACE AND LIGHT W ALOFT TONIGHT...INCREASING INTO 5 TO
10 KT RANGE TOMORROW AFTN.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z THURSDAY...

FORECAST CONFIDENCE: MEDIUM.

ALTERNATE SCENARIOS: STRATOCU MAY LINGER ACROSS SE OH/N WV
TONIGHT.

EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH:   TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW:    TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.

UTC 1HRLY       18   19   20   21   22   23   00   01   02   03   04   05
EST 1HRLY       13   14   15   16   17   18   19   20   21   22   23   00
CRW CONSISTENCY  H    H    H    H    H    H    H    M    M    M    M    M
HTS CONSISTENCY  H    H    H    H    H    H    H    M    M    M    M    M
BKW CONSISTENCY  M    H    H    H    H    H    H    M    M    M    M    M
EKN CONSISTENCY  H    H    H    H    H    H    H    M    M    M    M    M
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
CKB CONSISTENCY  M    M    H    H    H    H    H    M    M    M    M    M

AFTER 18Z THURSDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.

&&

$$
SYNOPSIS...ARJ/JMV/30
NEAR TERM...30
SHORT TERM...SL
LONG TERM...ARJ
AVIATION...30









AREA FORECAST DISCUSSION

NWS GREENVILLE-SPARTANBURG SC

 638 PM EST THU JAN 3 2013

.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE REGION THROUGH FRIDAY NIGHT BEFORE
BRIEFLY GIVING WAY TO A PERIOD OF MOISTURE RETURN LATE SATURDAY. DRY
AIR IS EXPECTED TO RETURN ON SUNDAY AND CONTINUE INTO EARLY NEXT
WEEK.

&&

.NEAR TERM /THROUGH FRIDAY/...
600 PM UPDATE...NORTHWEST HALF OF THE CWFA NOW CLEAR OF CIRRUS AND
COLD ADVECTION HAS MANAGED TO WIPE OUT MOST OF THE LOW STRATUS.
CLEARING TREND SLOWED A BIT WITH LOSS OF INSOLATION BUT DOES
CONTINUE. DOWNWARD MOTION FROM CAA AND DOWNSLOPING...IN ADDITION TO
LLVL DRYING...IS SEEN OVERNIGHT ON RAP MODEL CROSS SECTION THROUGH
THE AREA. THE PIEDMONT WILL CONTINUE TO SEE PARTLY CLOUDY SKIES
THROUGH 10 PM OR SO BUT EVENTUAL CLEARING IS EXPECTED. TEMPS TONIGHT
WERE REVISED USING 18Z BIAS CORRECTED GFS MOS WHICH APPROPRIATELY
REFLECTED A SLOWED COOLING TREND OVER THE PIEDMONT. LOWS HOWEVER ARE
SIMILAR TO PREVIOUS FORECAST.

AS OF 200 PM EST...LIGHT RADAR RETURNS FROM DRIZZLE ARE CONFINED TO
THE ERN THIRD OF THE FORECAST AREA THIS AFTERNOON. WILL CARRY PATCHY
DRIZZLE IN THESE AREAS ANOTHER HOUR OR TWO AS THE LAST VESTIGES OF
UPGLIDE END. OTHERWISE...WATER VAPOR IMAGERY SHOWS THE UPSTREAM
POSITIVELY TILTED TROUGH AXIS STRETCHING FROM THE MIDWEST TO THE SRN
PLAINS...WITH INCREASINGLY ZONAL FLOW DEVELOPING OVER THE SOUTHEAST
AHEAD OF THIS FEATURE. ONE IMPACT OF THE UPSTREAM TROUGH HAS BEEN
CONSIDERABLE MID AND HIGH LEVEL CLOUDS INHIBITING HEATING AND
SLOWING THE SCATTERING OF THE LOW CLOUDS EVEN AS THE UPGLIDE QUITS.
THE MOISTURE SHOULD STEADILY DIMINISH AS SFC HIGH PRES BUILDS IN
FROM THE W TONIGHT WITH MORE OF A DRYING NRLY FLOW. THIS WILL
FINALLY ALLOW THE LOW CLOUDS TO SCATTER THROUGHOUT THIS EVENING.
DESPITE THE DRIER AIR SPILLING IN ON N TO NW FLOW OVERNIGHT...PATCHY
FOG COULD DEVELOP TOWARD DAYBREAK IN SOME FOOTHILL/PIEDMONT
LOCATIONS.

ALTHOUGH PROFILES ARE DRIER THROUGH A DEEP LAYER ON FRI...A
PERSISTENT UPPER JET AXIS WILL KEEP SOME THIN HIGH CLOUDS IN PLACE
OVER THE FORECAST AREA. THE UPSTREAM WAVE WILL GRADUALLY REAMPLIFY
IN THE NRLY FLOW ON FRI...AND APPROACH THE NRN TIER LATE IN THE
DAY...BUT WITH LITTLE ATTENDANT MOISTURE. 850 MB NW DOWNSLOPING FLOW
ON FRI...ALONG WITH GREATER INSOLATION...WILL LEAD TO WARMER MAX
TEMPS. A WEAK LEE TROUGH WILL LIKELY SET UP ON FRI...WITH SW FLOW
FURTHER ASSISTING THE PIEDMONT WARMING.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
AS OF 200 PM THURSDAY...THE SHORT TERM MODELS STILL ARE ADVERTIZING A
TRANSITION FROM A SPLIT UPPER FLOW TO A PHASED PATTERN DURING THE
WEEKEND. THIS RESULTS IN UPPER RIDGING OVER THE SE STATES FRIDAY
NIGHT INTO SAT. 12Z MODEL SUITE IS IN FAIRLY GOOD AGREEMENT THAT AN
UPPER LOW IN THE VICINITY OF N TX AT 00Z SAT WILL MOVE QUICKLY NE
AND MINOR OUT OVER THE LOWER GREAT LAKES WITH A SHORT WAVE TROUGH
EXTENDING TO THE SOUTHWEST WHICH WILL RIPPLE ACROSS THE FORECAST
AREA SAT NIGHT. A MORE VIGOUROUS LOOKING UPPER TROUGH WILL APPROACH
LATE SUNDAY.

THIS FORECAST PERIOD WILL BEGIN QUIET AS SURFACE HIGH PRESSURE MOVES
OVER THE REGION FRIDAY NIGHT INTO SAT. AS THE HIGH MOVES TO THE EAST
SAT AFTERNOON...WEAK WARM ADVECTION WILL COMMENCE ALONG WITH AN
INCREASE IN UPPER CLOUD COVER. THE BIGGEST ISSUE IN THE FORECAST FOR
THIS PERIOD IS WHETHER ANY PRECIPITATION DEVELOPS ACROSS THE AREA SAT
NIGHT AS THE BEFOREMENTIONED UPPER TROUGH AND WEAK ASSOCIATED WEAK
FORCING OCCURS. THE NAM...ECM AND SREF CAMP STILL HAVE A LIGHT QPF
RESPONSE ACROSS THE AREA...WHILE THE GFS IS STILL STUBBORNLY BONE
DRY. HAVE OPTED TO MAINTAIN CONTINUITY WITH THE PREVIOUS FORECAST
AND SIDE TOWARD THE WETTER SOLUTION. TO CREATE THE POP FIELD...I
BLENDED THE 09Z 3 HOURLY SREF POPS WITH THE OFFICIAL FORECAST. THIS
YIELDS CHANCE POPS DEVELOPING WEST TO EAST ACROSS THE AREA SAT
NIGHT...MOVING EAST OF THE AREA DURING SUNDAY. THERE WILL BE A PTYPE
ISSUE AS TEMPS ARE FORECAST TO FALL BELOW FREEZING OVER MOST
MOUNTAIN AREAS SAT NIGHT. AN EXAMINATION OF MODEL SOUNDINGS
INDICATES A RATHER DEEP WARM NOSE ACROSS THE MOUNTAINS WHICH WOULD
SUPPORT MOSTLY A RAIN/FREEZING RAIN PTYPE DEPENDENT ON SURFACE
TEMPS. CAN`T RULE OUT SOME IP...BUT WILL GENERATE WX GRIDS AS EITHER
R/ZR. QPF WILL BE LIGHT SO DO NOT ANTICIPATE ANY SIGNIFICANT ICING
ISSUES WITH THIS EVENT.

FORCING AND MOISTURE MOVE EAST OF THE AREA BY SUNDAY AFTERNOON
ALLOWING FOR CLEARING. APPROACHING UPPER TROUGH LATE ON SUNDAY WILL
HAVE LITTLE MOISTURE TO WORK WITH. GENERATED MAX/MIN TEMPS WITH A
BLEND OF BIAS CORRECTED MAV/MET WITH OFFICIAL FORECAST. THIS
GENERATES MAX TEMPS NEAR TO A LITTLE ABOVE AVERAGE AND MINS NEAR AVE
FRI NIGHT AND ABOVE AVERAGE SAT NIGHT.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 145 PM EST THURSDAY...LOOKS LIKE A FAIRLY STRAIGHTFORWARD
MEDIUM RANGE FOR EARLY JANUARY. WE START SUNDAY EVENING WITH THE
PASSAGE OF A VERY DYNAMIC LOOKING SHORT WAVE. THIS FEATURE BRINGS
IMPRESSIVE QG FORCING AND DPVA AND FRONTOGENESIS...BUT VERY LITTLE
MOISTURE. SO...OTHER THAN GIVING A BIT OF A KICK DURING A BRIEF
PERIOD OF NW FLOW PRECIP PRODUCTION ON THE TN SIDE OF THE MTNS...
THE WAVE IS EXPECTED TO MOVE THROUGH WITHOUT MUCH TO SHOW FOR IT.
PRECIP CHANCES WERE LIMITED TO SLIGHT ON THE TN BORDER SUNDAY NIGHT
AND END BY DAYBREAK MONDAY AS THE LOW LEVEL MOISTURE PULLS NE
QUICKLY. FROM THAT POINT ONWARD...IN THE WAKE OF THE WAVE...UPPER
RIDGING BUILDS IN FOR THE EARLY PART OF THE WEEK. THIS WILL SUPPORT
DRY HIGH PRESSURE AT THE SURFACE FOR MONDAY THROUGH WEDNESDAY...AND
TEMPERATURES MODERATING BY ABOUT A CATEGORY EACH DAY. THE
OPERATIONAL GUIDANCE DEVIATES SUBSTANTIALLY BY THE END OF WEDNESDAY.
THE FCST FAVORS THE MUCH SLOWER 00Z ECMWF WHICH IS MORE IN LINE WITH
HPC GUIDANCE AS TO THE PROGRESSION OF AN UPPER TROF/LOW MOVING OVER
THE SRN PLAINS ON WEDNESDAY...KEEPING THE LOW CLOSED OFF AT 500 MB.
BY THE END OF THURSDAY...THE UPPER LOW SHOULD MOVE TOWARD THE
MIDWEST WITH THE SURFACE LOW REMAINING WELL TO OUR WEST. THIS
SCENARIO WOULD LIFT A WARM FRONTAL BOUNDARY PAST TO THE WEST
WEDNESDAY NIGHT. WARM ADVECTION AND CLOUDS WOULD KEEP MIN TEMPS
ABOVE FREEZING...SO LIGHT RAIN IS PREFERRED. ON THURSDAY...WE WOULD
BE IN A BROAD WARM SECTOR WITH TEMPS MODIFYING EVEN FURTHER.
INCREASING GULF MOISTURE WOULD SUPPORT THE DEVELOPMENT OF SHOWERS
OVER MOST OF GEORGIA AND THE WESTERN CAROLINAS. CONFIDENCE IN THE
TIMING OF THESE FEATURES IS FAIRLY LOW...BUT WE SHOULD HAVE ANOTHER
FRONTAL PASSAGE AT SOME POINT IN THE SECOND HALF OF NEXT WEEK.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
AT KCLT...DOWNSLOPING AND COLD AIR ADVECTION HAVE BROKEN UP THE
STRATUS WHICH LINGERED THROUGH THE DAY. THIS WILL CONTINUE INTO THE
NIGHT BUT SCATTERED MVFR-LEVEL CLOUDS WILL HANG ON FOR A TIME THIS
EVENING. SIMILARLY TO SITUATION AT 18Z PACKAGE...GUIDANCE GENERALLY
POINTING TO A FOG-FREE NIGHT. HOWEVER WITH SFC DEWPOINT REMAINING IN
THE MID 30S...AND COOLING UNDER THE CLEAR SKIES EXPECTED TO OUTPACE
THE DRYING FROM THE COLD ADVECTION...SOME LIGHT FOG COULD FORM IN
THE EARLY MORNING. THE LAMP IS THE ONLY MODEL REFLECTING THIS AND IT
HAS MVFR VSBY FOR A FEW HOURS. NOT EXCEEDINGLY CONFIDENT WITH THE
EXTENT OF ANY FOG SO MAINTAINED THE TEMPO FROM PREVIOUS ISSUANCE.
SFC HIGH TO OUR WEST TONIGHT WILL MAINTAIN NORTHERLY WINDS...BUT LEE
TROUGHING TOMORROW IS EXPECTED TO BRING WINDS AROUND TO THE
SOUTHWEST FOR THE DAYTIME HOURS.

ELSEWHERE...LOW STRATUS HAVE MOSTLY DISSIPATED THOUGH A FEW SITES
STILL REPORT FEW-SCT MVFR CLOUDS. THESE ARE EXPECTED TO BE
SHORT-LIVED AS LOW LEVEL COLD ADVECTION CONTINUES. LAMP GUIDANCE
BRINGS MVFR FOG TO MANY AREAS WHERE THE COLD ADVECTION GOT UNDERWAY
LATE...THAT IS THE AREAS WHERE STRATUS PERSISTED AND SFC DEWPOINTS
REMAIN IN THE MID 30S TO LOWER 40S PRESENTLY. WE CERTAINLY WILL BE
ABLE TO COOL BEYOND THOSE READINGS...BUT THE QUESTION IS...WILL THE
DEWPOINTS DROP FROM COLD ADVECTION FASTER THAN AIR TEMPS CAN COOL TO
SATURATION. UNCERTAINTY IN THIS POINT WARRANTS ONLY A TEMPO MENTION
FOR THE SC SITES...WITH KAVL AND KHKY MORE LIKELY TO DRY OUT BEFORE
THE AIR COOLS SUFFICIENTLY.

OUTLOOK...DRY HIGH PRES WILL PERSIST INTO SAT...WITH A QUICK MOVING
SYSTEM RETURNING FROM THE WEST THROUGH THE LATTER HALF OF THE
WEEKEND. RESTRICTIONS APPEAR DOUBTFUL AT THIS TIME AS THERE APPEARS
TO BE LIMITED MOISTURE RETURN. DRY HIGH PRES WILL THEN RETURN EARLY
NEXT WEEK.

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

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

&&

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

&&

$$
SYNOPSIS...CSH
NEAR TERM...HG/WIMBERLEY
SHORT TERM...LG
LONG TERM...PM
AVIATION...WIMBERLEY







AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

 942 AM CST WED JAN 2 2013

.DISCUSSION...
A QUICK UPDATE...LIGHT RAIN STILL FALLING OVER THE COASTAL
COUNTIES BUT IS LIGHT AND SOME SPRINKLES IN THE NEXT TIER OF
COUNTIES INLAND. MOIST AXIS OVERRUNNING THE COLD DOME WILL BE
SHIFTING EAST THROUGH THE AFTERNOON AND RAIN CHANCES WILL LIKELY
LOWER THROUGHOUT THE AFTERNOON FROM NORTHWEST TO SOUTHEAST. RAIN
COOLING SHOULD LESSEN AS WELL LATE IN THE AFTERNOON BUT HAVE
LOWERED TEMPERATURES A FEW DEGREES FOR THE COOLING. SKIES SHOULD
REMAIN CLOUDY MOST OF THE AFTERNOON IN THE EAST THEN IMPROVE AS
DRIER AIR ALOFT SPREADS INTO THE REGION. WITH A QUICK DIP IN
TEMPERATURES IN THE EVENING MAY NEED TO LOWER OVERNIGHT LOWS A
DEGREE OR TWO AS WELL BUT WILL WAIT TO GET A LOOK AT THE LATER
GUIDANCE BEFORE CHANGING THE MINS.
45

&&

.PREV DISCUSSION... /ISSUED 512 AM CST WED JAN 2 2013/

DISCUSSION...
SEE 12Z AVIATION DISCUSSION.

AVIATION...
NAM/GFS FCST SOUNDINGS SHOW MVFR CIGS MIXING OUT BY 15Z WHILE THE
RAP KEEPS CIGS IN PLACE THROUGH 18Z. THOUGHT THE RAP MIGHT HAVE A
BETTER HANDLE ON THINGS BUT LATEST OBS SHOW MVFR CIGS SCATTERING
OUT. FEEL VFR CONDS WILL DEVELOP BY AFTN BUT TIMING STILL A LITTLE
IFFY. WINDS WILL BE LIGHTER THAN YESTERDAY ALTHO BRIEFLY HIGHER
FOR A FEW HOURS AT KGLS EARLY THIS MORNING. RADAR SHOWS WIDESPREAD
LIGHT RAIN BUT OBSERVATION SITES NOT REPORTING RAIN SO IT IS
LIKELY VIRGA. WILL NOT BE CARRYING ANY MENTION OF PRECIP IN THIS
SET OF TAFS. 43

PREV DISCUSSION... /ISSUED 341 AM CST WED JAN 2 2013/

DISCUSSION...
BASED ON SFC OBS AND IR SATELLITE IMAGERY IT LOOKS LIKE THERE ARE
SEVERAL LAYERS OF CLOUDS WITH LOW MVFR OVC CLOUD DECK BEING THE
MOST PROMINENT. AREA RADAR ARE PICKING UP SOME LIGHT RETURNS FROM
MID AND HIGH LEVEL CLOUDS BUT NOTHING HITTING THE GROUND GIVEN DRY
AIR BELOW 700MB. PRECIP REMAINS CONFINED THE OFFSHORE WATERS OF
THE UPPER TX COAST. SFC ANALYSIS HAS WEAK HIGH PRESSURE OVER THE S
PLAINS WHICH SHOULD KEEP MODERATE NORTHERLY WINDS IN PLACE TODAY.
CLOUD COVER AND WINDS SHOULD HOLD TEMPS IN THE 40S FOR MUCH OF THE
DAY WITH MAX TEMPS POSSIBLY REACHING 50 IN A FEW SPOTS. CLOUD
COVER WILL BE SLOW TO ERODE GIVEN WESTERLY JET STREAM FLOW. COUPLE
OF SHORT WAVE TROUGHS ROTATING THROUGH A MEAN TROUGH OVER THE
PLAINS AND C ROCKIES AND THEN A CLOSED LOW OFF THE CALIFORNIA
COAST WILL MAINTAIN STRONG WESTERLY FLOW ALOFT THROUGH THE END OF
THE WEEK. GIVEN CONTINUED CLOUD COVER AND WEAK NORTHERLY
FLOW...WILL KEEP TEMPS A COUPLE OF DEGREES BELOW NORMAL FOR THE
REST OF THE WEEK.

BY FRIDAY MODELS ARE IN PRETTY GOOD AGREEMENT WITH UPPER LOW OVER
S ROCKIES. MODELS THEN BEGIN TO MOVE THIS LOW INTO W TX BY SAT
MORNING WITH SOME VORTICITY SHEARING OUT ACROSS THE PLAINS. GFS
SEEMS TO BE A BIT FAST WITH STRETCHING OUT THE TROUGH WHILE
ECMWF/NAM HAVE A BIT MORE PRONOUNCED TROUGH. MODELS KEEP BULK OF
LARGE SCALE ASCENT NORTH OF SE TX BUT STILL ENOUGH FORCING TO
TRIGGER SOME RAIN FOR SATURDAY. WILL KEEP 20 POPS IN THE FORECAST
FOR RAIN BUT A LOT OF THIS DEPENDS ON HOW STRONG ISENTROPIC LIFT
DEVELOPS AND IF ATMOSPHERIC COLUMN MOISTENS ENOUGH. NAM BUFR
SOUNDINGS SHOW SOME MOIST PROFILES BY 06-12Z SAT WHICH WOULD
SUPPORT RAIN.

HIGH PRESSURE BUILDS BACK OVER TX FOR EARLY NEXT WEEK. LOOKS LIKE
SOUTHERLY RETURN FLOW DOES NOT SET UP UNTIL TUE/WED NEXT WEEK IN
THE FAR EXTENDED FORECAST. UNTIL THEN TEMPS WILL BE VERY CLOSE TO
CLIMO NORMS.

39

MARINE...
HIGH PRESSURE BUILDING INTO THE SOUTHERN PLAINS WILL MAINTAIN A
TIGHT PRESSURE GRADIENT THROUGH THE END OF THE WEEK. A MODERATE
NORTH TO NORTHEAST FLOW IS EXPECTED TO PERSIST THROUGH THE END OF
THE WEEK. WINDS WILL GENERALLY STAY NEAR OR JUST BELOW SCA
CRITERIA THROUGH TONIGHT AND THEN BRIEFLY INCREASE AGAIN ON
THURSDAY. SCA/SCEC FLAGS WILL BE REQUIRED THROUGH THE END OF THE
WEEK. TIDE LEVELS HAVE FALL TO BETWEEN 0.5 AND 0.9 FEET BELOW
NORMAL. TIDE LEVELS ARE EXPECTED TO REMAIN NEAR TO SLIGHTLY BELOW
NORMAL THROUGH THE WEEKEND. A LOW WATER ADVISORY IS NOT
ANTICIPATED. 43

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      47  32  53  34  51 /  10  10  10  10  10
HOUSTON (IAH)              48  33  54  36  54 /  10  10  10  10  10
GALVESTON (GLS)            49  41  54  42  54 /  20  10  10  10  10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL NOON CST TODAY FOR THE
     FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY.

     SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH LATE TONIGHT FOR THE
     FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
     CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT
     20 NM.

     SMALL CRAFT ADVISORY UNTIL 3 PM CST THIS AFTERNOON 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.

     SMALL CRAFT SHOULD EXERCISE CAUTION FROM 3 PM CST THIS AFTERNOON
     THROUGH LATE TONIGHT 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...45




AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

 512 AM CST WED JAN 2 2013

.DISCUSSION...
SEE 12Z AVIATION DISCUSSION.

&&

.AVIATION...
NAM/GFS FCST SOUNDINGS SHOW MVFR CIGS MIXING OUT BY 15Z WHILE THE
RAP KEEPS CIGS IN PLACE THROUGH 18Z. THOUGHT THE RAP MIGHT HAVE A
BETTER HANDLE ON THINGS BUT LATEST OBS SHOW MVFR CIGS SCATTERING
OUT. FEEL VFR CONDS WILL DEVELOP BY AFTN BUT TIMING STILL A LITTLE
IFFY. WINDS WILL BE LIGHTER THAN YESTERDAY ALTHO BRIEFLY HIGHER
FOR A FEW HOURS AT KGLS EARLY THIS MORNING. RADAR SHOWS WIDESPREAD
LIGHT RAIN BUT OBSERVATION SITES NOT REPORTING RAIN SO IT IS
LIKELY VIRGA. WILL NOT BE CARRYING ANY MENTION OF PRECIP IN THIS
SET OF TAFS. 43

&&

.PREV DISCUSSION... /ISSUED 341 AM CST WED JAN 2 2013/

DISCUSSION...
BASED ON SFC OBS AND IR SATELLITE IMAGERY IT LOOKS LIKE THERE ARE
SEVERAL LAYERS OF CLOUDS WITH LOW MVFR OVC CLOUD DECK BEING THE
MOST PROMINENT. AREA RADAR ARE PICKING UP SOME LIGHT RETURNS FROM
MID AND HIGH LEVEL CLOUDS BUT NOTHING HITTING THE GROUND GIVEN DRY
AIR BELOW 700MB. PRECIP REMAINS CONFINED THE OFFSHORE WATERS OF
THE UPPER TX COAST. SFC ANALYSIS HAS WEAK HIGH PRESSURE OVER THE S
PLAINS WHICH SHOULD KEEP MODERATE NORTHERLY WINDS IN PLACE TODAY.
CLOUD COVER AND WINDS SHOULD HOLD TEMPS IN THE 40S FOR MUCH OF THE
DAY WITH MAX TEMPS POSSIBLY REACHING 50 IN A FEW SPOTS. CLOUD
COVER WILL BE SLOW TO ERODE GIVEN WESTERLY JET STREAM FLOW. COUPLE
OF SHORT WAVE TROUGHS ROTATING THROUGH A MEAN TROUGH OVER THE
PLAINS AND C ROCKIES AND THEN A CLOSED LOW OFF THE CALIFORNIA
COAST WILL MAINTAIN STRONG WESTERLY FLOW ALOFT THROUGH THE END OF
THE WEEK. GIVEN CONTINUED CLOUD COVER AND WEAK NORTHERLY
FLOW...WILL KEEP TEMPS A COUPLE OF DEGREES BELOW NORMAL FOR THE
REST OF THE WEEK.

BY FRIDAY MODELS ARE IN PRETTY GOOD AGREEMENT WITH UPPER LOW OVER
S ROCKIES. MODELS THEN BEGIN TO MOVE THIS LOW INTO W TX BY SAT
MORNING WITH SOME VORTICITY SHEARING OUT ACROSS THE PLAINS. GFS
SEEMS TO BE A BIT FAST WITH STRETCHING OUT THE TROUGH WHILE
ECMWF/NAM HAVE A BIT MORE PRONOUNCED TROUGH. MODELS KEEP BULK OF
LARGE SCALE ASCENT NORTH OF SE TX BUT STILL ENOUGH FORCING TO
TRIGGER SOME RAIN FOR SATURDAY. WILL KEEP 20 POPS IN THE FORECAST
FOR RAIN BUT A LOT OF THIS DEPENDS ON HOW STRONG ISENTROPIC LIFT
DEVELOPS AND IF ATMOSPHERIC COLUMN MOISTENS ENOUGH. NAM BUFR
SOUNDINGS SHOW SOME MOIST PROFILES BY 06-12Z SAT WHICH WOULD
SUPPORT RAIN.

HIGH PRESSURE BUILDS BACK OVER TX FOR EARLY NEXT WEEK. LOOKS LIKE
SOUTHERLY RETURN FLOW DOES NOT SET UP UNTIL TUE/WED NEXT WEEK IN
THE FAR EXTENDED FORECAST. UNTIL THEN TEMPS WILL BE VERY CLOSE TO
CLIMO NORMS.

39

MARINE...
HIGH PRESSURE BUILDING INTO THE SOUTHERN PLAINS WILL MAINTAIN A
TIGHT PRESSURE GRADIENT THROUGH THE END OF THE WEEK. A MODERATE
NORTH TO NORTHEAST FLOW IS EXPECTED TO PERSIST THROUGH THE END OF
THE WEEK. WINDS WILL GENERALLY STAY NEAR OR JUST BELOW SCA
CRITERIA THROUGH TONIGHT AND THEN BRIEFLY INCREASE AGAIN ON
THURSDAY. SCA/SCEC FLAGS WILL BE REQUIRED THROUGH THE END OF THE
WEEK. TIDE LEVELS HAVE FALL TO BETWEEN 0.5 AND 0.9 FEET BELOW
NORMAL. TIDE LEVELS ARE EXPECTED TO REMAIN NEAR TO SLIGHTLY BELOW
NORMAL THROUGH THE WEEKEND. A LOW WATER ADVISORY IS NOT
ANTICIPATED. 43

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      48  32  53  34  51 /  10  10  10  10  10
HOUSTON (IAH)              50  33  54  36  54 /  10  10  10  10  10
GALVESTON (GLS)            51  41  54  42  54 /  20  10  10  10  10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL NOON CST TODAY FOR THE
     FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY.

     SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH LATE TONIGHT FOR THE
     FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
     CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT
     20 NM.

     SMALL CRAFT ADVISORY UNTIL 3 PM CST THIS AFTERNOON 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.

     SMALL CRAFT SHOULD EXERCISE CAUTION FROM 3 PM CST THIS AFTERNOON
     THROUGH LATE TONIGHT 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 COLUMBIA SC

 432 AM EST FRI JAN 4 2013

.SYNOPSIS...
A WEAK SURFACE TROUGH WILL MOVE THROUGH TODAY. HIGH PRESSURE WILL
BUILD INTO THE REGION TONIGHT INTO SATURDAY. A FRONTAL SYSTEM
WILL PROVIDE A CHANCE OF RAIN SATURDAY NIGHT AND SUNDAY. FAIR
WEATHER EXPECTED EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...
RECENT OBSERVATIONS SUGGEST SOME VARIABILITY IN VISIBILITIES.
DENSE FOG MAY NOT BE WIDESPREAD ENOUGH TO WARRANT A DENSE FOG
ADVISORY...BUT COMBINATION OF PATCHY DENSE FOG AND TEMPERATURES
NEAR FREEZING WARRANTS A SPECIAL WEATHER STATEMENT FOR REDUCED
VISIBILITIES AND POSSIBILITY OF BLACK ICE ON BRIDGES.

PREVIOUS DISCUSSION...
MAIN NEAR TERM CONCERN IS POTENTIAL FOR DENSE FOG OVER MUCH OF THE
FORECAST AREA. WEAK INVERTED SURFACE TROUGH AND
ASSOCIATED CLOUDINESS SHIFTING SOUTH OF THE FA. DESPITE SOME WEAK
COOL AND DRY ADVECTION...LOW DEWPOINT DEPRESSIONS AND LIGHT WINDS
WHERE SKIES HAVE CLEARED HAS RESULTED IN FOG DEVELOPMENT OVER
THE NORTHERN FA...WITH VISIBILITIES ONE HALF MILE OF LESS IN SOME
LOCATIONS. LATEST NEAR TERM HIGH RESOLUTION MODELS SUGGEST DENSE
FOG COULD SPREAD SW INTO THE CENTRAL FA AND POSSIBLY PORTIONS OF
THE CSRA LATER TONIGHT. WILL HAVE TO MONITOR FOR THE POSSIBILITY OF
ISSUING A DENSE FOG ADVISORY. IMPORTANT NOTE...TEMPERATURES WILL
BE NEAR OR BELOW FREEZING IN SOME LOCATIONS ACROSS THE NORTHERN
AND CENTRAL FA WHERE DENSE FOG MAY FORM. THIS COULD LEAD TO SOME
BLACK ICE OR SLICK SPOTS ON BRIDGES AND OVERPASSES. IF THIS
APPEARS TO DEVELOP...WILL HANDLE WITH SPECIAL WEATHER STATEMENT.

OTHERWISE...FAIR AND DRY WEATHER EXPECTED TODAY...WITH SUNNY SKIES
EXPECTED AFTER MORNING FOG DISSIPATED. HIGH PRESSURE WILL REMAIN
CENTERED TO OUR WEST TODAY...AS A WEAK SURFACE TROUGH AHEAD OF AN
UPPER DISTURBANCE...MOVES THROUGH THIS AFTERNOON.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
FAIR WEATHER EXPECTED THROUGH SATURDAY...AS SURFACE HIGH PRESSURE
BUILDS INTO THE REGION WITH A DRY ATMOSPHERE IN PLACE. AN UPPER
TROUGH WILL LIFT NE OUT OF THE SOUTHERN PLAINS AND LOWER MISS
VALLEY SATURDAY NIGHT BRINGING INCREASING CLOUDINESS AND THE
POSSIBILITY OF SHOWER ACTIVITY INTO OUR REGION LATE SATURDAY
NIGHT.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
NO SIGNIFICANT CHANGES WERE MADE TO THE FORECAST FOR THIS TIME
PERIOD. PREVIOUS DISCUSSION FOLLOWS...

THERE IS CONSIDERABLE UNCERTAINTY NOTED IN THE ENSEMBLE POP
GUIDANCE THROUGH MONDAY WITH THE OPERATIONAL GFS QUITE DRY.
THERE IS UNCERTAINTY LATE IN THE PERIOD AS ANOTHER UPPER LOW MOVES
SLOWLY NORTHEAST.

THE UPPER RIDGE WILL SHIFT EAST INTO THE CENTRAL CONUS SUN/MON.
A WEAK SURFACE FRONT WILL MOVE THROUGH THE REGION SUNDAY.
FORECASTED CHANCE POPS SUNDAY AND WITH CLOUDINESS MOST OF THE DAY
PREFER THE COOLER TEMPERATURE GUIDANCE. CONFIDENCE LIMITED AT THIS
TIME. SURFACE HIGH PRESSURE WILL BUILD INTO THE AREA BEHIND THE
FRONT EARLY TO MID NEXT WEEK. THE MODELS KEEP THE MAIN UPPER FLOW
WELL TO THE NORTH...WITH A CUT-OFF LOW DEVELOPING OVER THE SW
CONUS....AND A SW UPPER FLOW AND HEIGHT RISES OVER OUR REGION.
THIS WILL ALLOW THE AIR MASS TO MODIFY EARLY NEXT WEEK WITH HIGH
TEMPERATURES INCREASING TO ABOVE NORMAL. THERE IS UNCERTAINTY
AGAIN LATE IN THE PERIOD. THE GFS IS MUCH FASTER THAN THE ECMWF
EJECTING AN UPPER-LEVEL LOW NORTHEAST FROM THE DESERT SOUTHWEST.
THE GFS IS MUCH WETTER MIDWEEK. PREFER A SLOWER SOLUTION BECAUSE
AN UPSTREAM KICKER APPEARS TO BE LACKING SO KEPT A DRY FORECAST
UNTIL VERY LATE IN THE PERIOD.

&&

.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
BOTH MODELS AND SATELLITE IMAGERY SHOWS DRIER AIR MOVING IN MAINLY
FROM 2 KFT AND ABOVE. RUC FORECAST SOUNDINGS KEEP SOME LEVEL MOISTURE
CLOSE TO THE SURFACE. SATELLITE SHOWS CLEARING MOVING SOUTH. THIS
IS EXPECTED TO ALLOW FOR RADIATIONAL COOLING AND THE POSSIBILITY
OF RADIATIONAL FOG DEVELOPING. TEMPERATURES HAVE DROPPED TO NEAR
DEWPOINT READINGS ACROSS THE REGION. THIS SHOULD ALLOW FOR
WIDESPREAD FOG. IFR CONDITIONS PREVAIL AT CAE/CUB/OGB. STILL NOT
IFR AT AGS/DNL BUT WITH ADDITIONAL RADIATIVE COOLING...EXPECT IFR
CONDITIONS THESE TAF SITES ALSO BY 10-11Z. VSBYS HAVE REMAINED 1/2
MILE OR GREATER ACROSS AREA. ALTHOUGH OGB DROPPED TO 1/4 MILE. SO
NO WIDESPREAD DENSE FOG FOR TIME BEING BUT WILL CONTINUE TO
MONITOR. AFTER SUNRISE...WITH SOLAR HEATING...EXPECT FOG TO BREAK
UP BY 14Z WITH VFR CONDITIONS BY 15Z.

EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE SATURDAY NIGHT AND
SUNDAY WITH FRONTAL SYSTEM IN THE VICINITY.

&&

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

$$







AREA FORECAST DISCUSSION

NWS PEACHTREE CITY GA

 321 AM EST FRI JAN 4 2013

.SHORT TERM /TODAY THROUGH SATURDAY NIGHT/...
MODELS IN PRETTY GOOD AGREEMENT THROUGH 48 HOURS. A NARROW BAND OF
LOW CLOUDS WILL MOVE INTO CENTRAL GA BY 12Z AND THEN DISSIPATE AFTER
SUNRISE. THIS SHOULD MAKE FOR A MOSTLY SUNNY DAY AND MOSTLY CLEAR
NIGHT TONIGHT. THE NEXT SYSTEM IS CURRENTLY ORGANIZING OVER THE
SOUTHERN ROCKIES AND WILL MOVE RAPIDLY NORTHEAST AND WEAKEN OVER THE
NEXT 48 HOURS. THIS WILL BRING A WEAK SHORT WAVE OVER THE CWA LATE
SATURDAY INTO SATURDAY NIGHT. THE SYSTEM WILL BE LACKING
MOISTURE...HOWEVER THERE SHOULD BE ENOUGH MOISTURE FOR SCATTERED
SHOWERS...MOVING INTO THE WESTERN HALF OF THE CWA SATURDAY AFTERNOON
AND ACROSS THE ENTIRE CWA SATURDAY NIGHT. TEMPERATURES SATURDAY
NIGHT SHOULD BE WARM ENOUGH FOR THE PRECIP TO FALL AS RAIN...DO NOT
EXPECT ANY FROZEN PRECIP SATURDAY NIGHT.

GUIDANCE HAS NOT BEEN DOING TOO WELL WITH TEMPS. LOCAL BIAS TABLES
INDICATE GUIDANCE HAS BEEN RUNNING 2 TO 4 DEGREES TOO WARM FOR
DAYTIME HIGHS AND 2 TO 4 DEGREES TOO COLD FOR NIGHTTIME LOWS OVER
THE PAST 5 TO 10 DAYS WITH THE NAM HAVING THE LARGEST BIAS ERRORS.
HAVE THEREFORE MADE ADJUSTMENTS FOR THIS IN MAX AND MIN TEMPS TODAY
THROUGH SATURDAY NIGHT.

17


.LONG TERM /SUNDAY THROUGH THURSDAY/...
THE LAST IN A SERIES OF QUICK MOVING SHORT WAVES SWEEPS BY TO THE
NORTH OF GEORGIA SUNDAY...BUT MODELS ARE NOT GENERATING ANY
SIGNIFICANT PRECIPITATION ASSOCIATED WITH THIS. I HAVE KEPT SOME
LINGERING POPS IN THE SOUTHEAST SUNDAY...BUT THIS IS GENERALLY FOR
EARLY IN THE DAY WITH THE EXITING INITIAL SYSTEM. GFS AND ECMWF
CONTINUE TO HAVE NOTICEABLE DIFFERENCES IN THE LONGER TERM TRENDS
WITH THE GFS CONTINUING TO BE MORE OPEN AND PROGRESSIVE WITH THE
UPPER LEVEL PATTERN. BOTH SHOW RIDGING ACROSS THE REGION AT THE
BEGINNING OF THE WEEK...HOWEVER THEY DIFFER SIGNIFICANTLY ON THE
RESOLUTION OF THE NEXT UPPER TROUGH/LOW. GFS KEEPS THIS WAVE OPEN AND
MOVES IT ACROSS THE CENTRAL/SOUTHERN ROCKIES AND OUT ONTO THE PLAINS
BY MIDWEEK WHILE THE ECMWF CLOSES OF THE LOW AND DIGS IT INTO THE BIG
BEND REGION. GFS SWEEPS A FAIRLY SHARP AND DEEP TROUGH ACROSS THE
FORECAST AREA WEDNESDAY WITH AN ASSOCIATED STRONG FRONTAL BOUNDARY
SWEEPING ACROSS GEORGIA. EURO- MODEL LIFTS THE LOW SHARPLY NORTHEAST
INTO THE GREAT LAKES BY THE LATTER HALF OF THE WEEK. THE GFS IS
GENERATING PRECIPITATION ACROSS THE AREA BEGINNING AS EARLY AS
TUESDAY NIGHT WITH HIGHEST QPF NUMBERS WEDNESDAY...AND THEN ENDS
PRECIPITATION BY THURSDAY MORNING. ECMWF KEEPS THE STATE DRY THROUGH
MUCH OF WEDNESDAY NIGHT AND ONLY SPREADS MINIMAL QPF NUMBERS ACROSS
THE FORECAST AREA THURSDAY. I AM BASING MY EXTENDED FORECAST
GENERALLY ON THE GFS SOLUTION. THE 00Z NAM ENDS ITS RUN AT 12Z MONDAY
IN FAIRLY GOOD AGREEMENT WITH THE MORE OPEN/PROGRESSIVE GFS. THIS
WOULD BRING THE BETTER CHANCES FOR PRECIPITATION TO THE AREA
WEDNESDAY/WEDNESDAY NIGHT WHICH IS A BIT FASTER THAN THE PREVIOUS
EXTENDED FORECAST GRIDS. RIGHT NOW INSTABILITY IS MARGINAL AT BEST
FOR THUNDER AND WITH SUCH UNCERTAINTY CONTINUING IN THE ULTIMATE
SOLUTION FOR THIS WHOLE SYSTEM I WILL REFRAIN FROM MENTIONING THUNDER
FOR NOW.

20


&&

AVIATION...
06Z UPDATE...
A BAND OF MVFR CLOUDS WAS MOVING SOUTHWEST OUT OF SC AND INTO
EASTERN GA. RUC AND MAV HAVE THIS AREA MOVING INTO CENTRAL GA BY
12Z. THIS AREA JUST BRUSHES THE ATL AREA AND WILL NEED TO ADD SCT015
AFTER 10Z. THIS AREA SHOULD MOVE INTO MCN AND WILL ADD A SCT TEMPO
BKN015. THESE LOW CLOUDS SHOULD DISSIPATE AFTER 14Z AND THEN
CONDITIONS SHOULD BE VFR FOR THE REST OF THE FORECAST. WINDS WILL BE
NEAR CALM EARLY THIS MORNING...NORTHWEST LESS THAN 10 KTS DURING THE
DAY AND THEN DIMINISHING AFTER SUNSET TO NEAR CALM.

//ATL CONFIDENCE...06Z UPDATE...
MEDIUM ON MVFR CLOUDS EARLY THIS MORNING.
HIGH ON ALL REMAINING ELEMENTS.

17

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          53  31  53  39 /   0   0  10  20
ATLANTA         51  32  51  40 /   0   0  30  30
BLAIRSVILLE     47  27  49  34 /   0   0  20  20
CARTERSVILLE    49  27  49  35 /   0   0  30  20
COLUMBUS        56  34  57  43 /   0   0  30  30
GAINESVILLE     50  31  51  38 /   5   0  20  20
MACON           55  31  58  40 /   0   0  10  30
ROME            50  28  51  34 /   0   0  30  20
PEACHTREE CITY  51  30  51  37 /   0   0  30  30
VIDALIA         55  38  59  48 /   0   0   5  30

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...17
LONG TERM....20
AVIATION...17






AREA FORECAST DISCUSSION...UPDATE

NWS PEACHTREE CITY GA

 1228 AM EST FRI JAN 4 2013

.EVENING UPDATE...
/ISSUED AT 1022 PM EST THU JAN 3 2013/
SKIES HAVE CLEARED AS EXPECTED WITH A NW WIND FLOW SPREADING A DRY
AND COLD AIR MASS OVER THE FORECAST AREA. DEWPOINTS IN THE 20S AND
30S STILL SUPPORT PROJECTED OVERNIGHT LOWS OF THE SAME. MAY SEE SOME
PATCHY FOG BRIEFLY DOWN AROUND EASTMAN... SWAINSBORO AND VIDALIA
WHERE THE WARMER DEWPOINTS IN THE UPPER 30S ARE NOTED... BUT THIS
SHOULD BE SHORT LIVED AS DRIER AIR CONTINUES TO SPREAD SOUTHWARD
OVERNIGHT. OTHERWISE... NO MAJOR CHANGES TO THE FORECAST SEEM
NECESSARY AT THIS TIME. /39


.SHORT TERM /TONIGHT THROUGH SATURDAY/...
/ISSUED AT 230 PM EST THU JAN 3 2013/
A WEAK WAVE CURRENTLY MOVING ACROSS SOUTH GEORGIA HAS BROUGHT
INCREASED CLOUD COVER TO THE REGION WITH SHOWERS ACROSS SOUTH AND
CENTRAL GA. HIGH PRESSURE IS BEGINNING TO BUILD EAST OUT OF THE
CENTRAL PLAINS AND WILL CONTINUE SO THROUGH FRIDAY. THIS RIDGE WILL
BECOME CENTERED OVER GA BY 00-06Z SAT. THIS RIDGE WILL KEEP NORTH
AND CENTRAL GA PRECIPITATION FREE TONIGHT THROUGH SAT MORNING. THERE
IS ANOTHER WAVE THAT MOVES NORTH OUT OF THE GULF SAT. THIS SECOND
WAVE SHOULD BRING MORE PRECIP TO THE AREA BUT THE MODELS SHOW IT
DRYING AS IT MOVES ACROSS THE STATE. THIS WAVE MOVES RIGHT INTO THE
BACKSIDE OF THE HIGH PRESSURE RIDGE THAT WILL ALREADY BE IN PLACE.
JUST HOW MUCH RAIN WILL DEPEND OF HOW STRONG THE RIDGE IS OR HOW
STRONG THE WAVE IS. WILL HAVE TO MONITOR THIS SITUATION OVER THE
NEXT FEW DAYS.

01

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
/ISSUED AT 230 PM EST THU JAN 3 2013/
GFS/NAM SIGNIFICANTLY DIFFERING WITH RAIN CHANCES SATURDAY NIGHT.
HAVE TWEAKED THE FORECAST TO REFLECT A COMPROMISE BETWEEN A WETTER
NAM AND A DRIER GFS. EITHER WAY RAIN AMOUNTS SHOULD BE LIGHT.
TOO MUCH UNCERTAINTY BEYOND TO MAKE MAJOR CHANGES AT THIS
TIME...ESPECIALLY IN THE WEDNESDAY TO THURSDAY TIME FRAME WITH THE
12Z GFS MUCH FASTER THAN THE 12Z EUROPEAN WITH THE NEXT WEATHER
SYSTEM.

BDL

PREVIOUS DISCUSSION...
BOTH THE GFS AND ECMWF CONTINUE WITH THE SHORTWAVES MOVING ACROSS
THE GULF...WHILE THE NEXT POTENTIAL WEATHER MAKER MOVES INTO THE
MID-MISSISSIPPI VALLEY. THE GFS HAS A MUCH DEEPER LAYER OF
MOISTURE ASSOCIATED WITH THIS SYSTEM. AS IT LIFTS INTO THE OHIO
VALLEY...IT POSES A THREAT OF LIGHT RAIN FOR NORTHWEST GEORGIA
SATURDAY AFTERNOON..WHILE A LOW MOVING FROM THE WESTERN GULF
SPREADS MOISTURE INTO SOUTHEAST GEORGIA THAT COULD RENDER SOME
BRIEF LIGHT RAIN TO THE AREA SATURDAY NIGHT INTO SUNDAY MORNING.
THE PASSING OF THESE SYSTEMS WILL LEAVE THE AREA WITH DRY
CONDITIONS ONCE AGAIN...WHICH CURRENTLY GOES THROUGH WEDNESDAY.

37

&&

.AVIATION...
06Z UPDATE...
A BAND OF MVFR CLOUDS WAS MOVING SOUTHWEST OUT OF SC AND INTO
EASTERN GA. RUC AND MAV HAVE THIS AREA MOVING INTO CENTRAL GA BY
12Z. THIS AREA JUST BRUSHES THE ATL AREA AND WILL NEED TO ADD SCT015
AFTER 10Z. THIS AREA SHOULD MOVE INTO MCN AND WILL ADD A SCT TEMPO
BKN015. THESE LOW CLOUDS SHOULD DISSIPATE AFTER 14Z AND THEN
CONDITIONS SHOULD BE VFR FOR THE REST OF THE FORECAST. WINDS WILL BE
NEAR CALM EARLY THIS MORNING...NORTHWEST LESS THAN 10 KTS DURING THE
DAY AND THEN DIMINISHING AFTER SUNSET TO NEAR CALM.

//ATL CONFIDENCE...06Z UPDATE...
MEDIUM ON MVFR CLOUDS EARLY THIS MORNING.
HIGH ON ALL REMAINING ELEMENTS.

17

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          30  52  31  53 /   0   0   0  10
ATLANTA         31  51  33  51 /   0   0   0  10
BLAIRSVILLE     26  50  26  51 /   0   0   0  20
CARTERSVILLE    27  50  28  51 /   0   0   0  20
COLUMBUS        33  55  33  56 /   0   0   0  20
GAINESVILLE     31  51  32  52 /   0   5   0  20
MACON           32  55  31  56 /   0   0   0  10
ROME            25  51  26  51 /   0   0   5  30
PEACHTREE CITY  27  51  28  51 /   0   0   0  10
VIDALIA         36  60  38  60 /   5   0   0  20

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...01/39
LONG TERM....BDL
AVIATION...39





















AREA FORECAST DISCUSSION

NWS JACKSON KY

 255 AM EST FRI JAN 4 2013

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 240 AM EST FRI JAN 4 2013

STILL NO SIGNIFICANT SYSTEMS TO CONTEND WITH IN THE SHORT TERM...BUT
THERE AREA A COUPLE OF ANNOYING ITEMS.

THE FIRST OF THESE IS THE LOW CLOUD DECK WHICH HAS BEEN SLOWLY
SINKING SOUTH OVER THE OHIO VALLEY DURING THE NIGHT. THE NAM IS NOT
MUCH HELP...ONCE AGAIN DOING VERY POORLY HANDLING LOW LEVEL MOISTURE.
THE GFS AT LEAST KNEW THAT IT WAS THERE...BUT THE CLOUDS HAVE
PROGRESSED SOUTH DURING THE NIGHT A BIT MORE THAN THE GFS SHOWED. THE
RUC IS PERHAPS PERFORMING THE BEST...BUT IS ONLY AVAILABLE THROUGH
18Z FRIDAY. WILL USE THE RUC THROUGH ITS PERIOD OF AVAILABILITY...AND
FOLLOW UP WITH THE GFS TREND OF DRYING UP THE CLOUDS DURING THE LATE
AFTERNOON AND EARLY EVENING.

RIDGING BUILDING IN AT THE SURFACE AND ALOFT SHOULD BRING MAINLY
CLEAR SKIES TONIGHT INTO SATURDAY MORNING.

AN UPPER LOW CURRENTLY OVER THE SOUTHWEST CONUS IS EXPECTED TO BE
PICKED UP BY AN UPPER LEVEL NORTHERN STREAM TROUGH DROPPING INTO THE
NORTH CENTRAL CONUS ON SATURDAY. AS THE UPPER LOW HEADS NORTHEAST TO
THE OHIO VALLEY...WE WILL SEE MID AND UPPER LEVEL CLOUDS INCREASE.
VIRGA WILL EVENTUALLY WORK TO MOISTEN LOWER LEVELS...AND SOME LIGHT
PRECIP CAN NOT BE RULED OUT LATE SATURDAY OR SATURDAY EVENING.
HOWEVER...ABOUT THE TIME THE LOWER LEVELS MOISTEN...MID/UPPER LEVEL
DRYING IS FORECAST AS THE SYSTEM ALOFT DEPARTS. THIS WILL LEAVE A
NARROW WINDOW OF OPPORTUNITY FOR PRECIP...AND HAVE ONLY USED 20
PERCENT POPS. CONDITIONS LOOK MARGINAL FOR RAIN VERSUS SNOW.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 255 AM EST FRI JAN 4 2013

THE MODELS START OFF IN GOOD AGREEMENT AND REMAIN IN GOOD AGREEMENT
THROUGH TUESDAY. HOWEVER...STILL SIGNIFICANT TIMING ISSUES WITH THE
NEXT WEATHER MAKER TOWARDS THE MIDDLE OF NEXT WEEK...LEADING TO VERY
LOW CONFIDENCE AT THIS TIME.

STARTING OFF THE FORECAST ON SUNDAY...IT LOOKS LIKE A TRANQUIL
PERIOD OF WEATHER IS EXPECTED DURING THE DAY...BUT A FAST MOVING
CLIPPER WILL DROP SOUTHEAST AND PROVIDE A QUICK SHOT FOR SOME
ISOLATED SNOW SHOWERS TOWARDS 00Z MONDAY. MOISTURE REMAINS VERY
WEAK...BUT UPSLOPE FLOW COULD HELP GENERATE THE NEEDED LIFT FOR A
FEW SNOW SHOWERS. NOT ANTICIPATED ANY ACCUMULATIONS AT THIS TIME.
MID LEVEL RIDING WILL SPREAD INTO THE AREA BY DAYBREAK MONDAY...WITH
CLEAR SKIES RETURNING. THIS WILL YIELD ANOTHER COLD START TO THE
DAY...BUT WE SHOULD SEE A NICE RECOVERY UNDER SUNNY SKIES ON MONDAY.
AS THE HIGH PRESSURE RIDGE PUSHES EAST...RETURN FLOW WILL ALLOW FOR
A FAIRLY GOOD WARM UP FOR THE EARLY TO MIDDLE PORTIONS OF NEXT WEEK.
HIGHS TUESDAY...WEDNESDAY...AND THURSDAY COULD PUSH 50 OR EXCEED IT.
HOWEVER...THE BIG QUESTION REMAINS HOW FAST THE NEXT WEATHER SYSTEM
ARRIVES FROM THE DESERT SOUTHWEST. GFS HAS ACTUALLY SPED UP THE
SYSTEM EVEN MORE AND NOW BRINGS A FAIRLY ROBUST SHORTWAVE TROUGH
INTO THE OHIO RIVER VALLEY ON WEDNESDAY. THE 00Z ECMWF REMAINS MUCH
SLOWER WITH THE MAIN SYSTEM NOT ARRIVING UNTIL THURSDAY. THE GFS
ENSEMBLE MEMBERS REMAIN IN CONSIDERABLE DISAGREEMENT...SO PLAN TO
KEEP A BROAD PERIOD OF LOW POPS IN THE FORECAST FROM LATE TUESDAY
NIGHT THROUGH THURSDAY EVENING. WITH THE WARM AIRMASS IN PLACE...AND
NO COLD AIR WRAPPING INTO THIS SYSTEM...PRECIPITATION WILL REMAIN ON
RAIN.

REGARDLESS OF THE TIMING OF THIS SYSTEM...IT LOOKS LIKE DRIER
WEATHER SHOULD RETURN BY FRIDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 116 AM EST FRI JAN 4 2013

MOSTLY VFR IS EXPECTED THROUGH THE PERIOD...WITH WINDS OF 10 KT OR
LESS. A POSSIBLE EXCEPTION WILL BE IN THE NORTHERN END OF THE
FORECAST AREA AROUND FLEMINGSBURG...MOUNT STERLING...AND MOREHEAD...
WHERE MVFR CEILINGS MAY BE PRESENT AT TIMES THROUGH FRIDAY MORNING.


&&

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

$$

SHORT TERM...HAL
LONG TERM....KAS
AVIATION...HAL







AREA FORECAST DISCUSSION

NWS JACKSON KY

 241 AM EST FRI JAN 4 2013

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 240 AM EST FRI JAN 4 2013

STILL NO SIGNIFICANT SYSTEMS TO CONTEND WITH IN THE SHORT TERM...BUT
THERE AREA A COUPLE OF ANNOYING ITEMS.

THE FIRST OF THESE IS THE LOW CLOUD DECK WHICH HAS BEEN SLOWLY
SINKING SOUTH OVER THE OHIO VALLEY DURING THE NIGHT. THE NAM IS NOT
MUCH HELP...ONCE AGAIN DOING VERY POORLY HANDLING LOW LEVEL MOISTURE.
THE GFS AT LEAST KNEW THAT IT WAS THERE...BUT THE CLOUDS HAVE
PROGRESSED SOUTH DURING THE NIGHT A BIT MORE THAN THE GFS SHOWED. THE
RUC IS PERHAPS PERFORMING THE BEST...BUT IS ONLY AVAILABLE THROUGH
18Z FRIDAY. WILL USE THE RUC THROUGH ITS PERIOD OF AVAILABILITY...AND
FOLLOW UP WITH THE GFS TREND OF DRYING UP THE CLOUDS DURING THE LATE
AFTERNOON AND EARLY EVENING.

RIDGING BUILDING IN AT THE SURFACE AND ALOFT SHOULD BRING MAINLY
CLEAR SKIES TONIGHT INTO SATURDAY MORNING.

AN UPPER LOW CURRENTLY OVER THE SOUTHWEST CONUS IS EXPECTED TO BE
PICKED UP BY AN UPPER LEVEL NORTHERN STREAM TROUGH DROPPING INTO THE
NORTH CENTRAL CONUS ON SATURDAY. AS THE UPPER LOW HEADS NORTHEAST TO
THE OHIO VALLEY...WE WILL SEE MID AND UPPER LEVEL CLOUDS INCREASE.
VIRGA WILL EVENTUALLY WORK TO MOISTEN LOWER LEVELS...AND SOME LIGHT
PRECIP CAN NOT BE RULED OUT LATE SATURDAY OR SATURDAY EVENING.
HOWEVER...ABOUT THE TIME THE LOWER LEVELS MOISTEN...MID/UPPER LEVEL
DRYING IS FORECAST AS THE SYSTEM ALOFT DEPARTS. THIS WILL LEAVE A
NARROW WINDOW OF OPPORTUNITY FOR PRECIP...AND HAVE ONLY USED 20
PERCENT POPS. CONDITIONS LOOK MARGINAL FOR RAIN VERSUS SNOW.

.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 240 AM EST FRI JAN 4 2013

AN UPDATED LONG TERM DISCUSSION WILL BE ISSUED SHORTLY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 116 AM EST FRI JAN 4 2013

MOSTLY VFR IS EXPECTED THROUGH THE PERIOD...WITH WINDS OF 10 KT OR
LESS. A POSSIBLE EXCEPTION WILL BE IN THE NORTHERN END OF THE
FORECAST AREA AROUND FLEMINGSBURG...MOUNT STERLING...AND MOREHEAD...
WHERE MVFR CEILINGS MAY BE PRESENT AT TIMES THROUGH FRIDAY MORNING.


&&

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

$$

SHORT TERM...HAL
LONG TERM....GEOGERIAN
AVIATION...HAL







AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

 410 AM EST FRI JAN 4 2013

.SYNOPSIS...
SEASONABLY COLD WEATHER WILL CONTINUE INTO THE WEEKEND. A SERIES
OF DISTURBANCES WILL SPAWN THE NEXT CHANCE FOR SNOW SHOWERS ON
SATURDAY NIGHT AND SUNDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STRATOCU BLANKET PERSISTS OVR THE UPR OH REGION THIS MRNG AS
SHRTWV...BEST EXHIBITED VIA MID LVL THERMAL TROF IN RAP MDL AND BY
IR SATELLITE PICS...CONTS EWD PROGRESS. NO MORE THAN FLURRIES OR
AN ISOLD SHSN ARE ANTICIPATED WITH THIS SYSTEM DURING THE MRNG.

TEMPS WERE FORECAST ABOUT 5 DEGREES UNDR THE AVERAGES USING
TWEAKED NAM GUIDANCE.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
A GENERALLY DRY AND BELOW NORMAL PERIOD WILL PERSIST ACROSS THE
AREA HEADING INTO THE WEEKEND. DECENT MODEL AGREEMENT EXISTS ON AT
LEAST SOME CLEARING WITH LITTLE CHANCE OF PRECIPITATION UNTIL
SATURDAY NIGHT/SUNDAY. AT THAT TIME...THE MODELS TRACK A DUET OF
SHRTWVS ACRS THE AREA. DUE TO THEIR CONTINENTAL ORIGINS...NEITHER
OF THESE LOOK TO BE PARTICULARLY MOISTURE-LADEN...SO POPS WERE
KEPT TO THE CHANCE CATEGORY FOR THE MOMENT. HOWEVER THROUGHOUT THE
PERIOD...THERMAL PROFILES FROM THE CONSENSUS FAVOR DEEP ENOUGH
COLD AIR TO SUPPORT SNOW THROUGHOUT THEIR PASSAGE.

WHILE TEMPERATURES REMAIN BELOW NORMAL...THEY DO MODERATE FAIRLY
SIGNIFICANTLY TOWARD THE MID 30S BY THE END OF THE WEEKEND.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
BLEND OF RECENT MEDIUM RANGE MODELS SHOW LINGERING POST SYSTEM
CLOUDS ACROSS THE UPPER OHIO VALLEY INTO MONDAY. ENSUING HIGH
PRESSURE WILL PROMOTE A DRY PERIOD INTO MID WEEK.

JUDGING FROM RECENT GFS AND ECMWF MOS...EXPECT TEMPERATURES TO BE
NEAR SEASONABLE LEVELS.

&&

.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
STRATOCU CLOUD DECK WILL PROVIDE MVFR RESTRICTIONS AT ALL PORTS
THROUGH AT LEAST DAWN. WAA WILL BEGIN IN ERNEST AFTER DAWN...ERODING
THE CLOUD FROM WEST TO EAST DURING THE MORNING HOURS. THIS WILL
RETURN MOST PORTS TO VFR. AS PER USUAL...THE COLD AIR WILL GET HUNG
UP ACROSS THE NORTH...KEEPING FKL AND DUJ IN MVFR.

NAM MODEL PROFILES SHOW VERTICAL MIXING WILL CAUSE SURFACE
WINDS...FROM THE SOUTHWEST THIS AFTERNOON...TO INCREASE TO 10 KTS
WITH GUSTS TO ABOUT 20 KTS. WINDS CAN BE A TAD MORE WESTERLY TONIGHT
AND LESS GUSTY. WINDS FRIDAY CAN AGAIN BE SOUTHWEST AT 10 KTS WITH
GUSTS TO 20 KTS.

.OUTLOOK.../SATURDAY THROUGH TUESDAY/...
VFR UNTIL POSSIBLE RESTRICTIONS SATURDAY NIGHT AND SUNDAY AS A
WEAK COLD FRONT MOVES ACROSS THE GREAT LAKES.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$
15/22






AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

 107 AM EST FRI JAN 4 2013

.SYNOPSIS...
A DISTURBANCE MOVING OFF THE GREAT LAKES MAY SPAWN SCATTERED
LIGHT SNOW SHOWERS TONIGHT. OTHERWISE...SEASONABLY COLD WEATHER
WILL CONTINUE INTO THE WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
STRATOCU BLANKET PERSISTS OVR THE UPR OH REGION THIS MRNG AS
SHRTWV...BEST EXHIBITED VIA MID LVL THERMAL TROF IN RAP MDL AND BY
IR SATELLITE PICS...CONTS EWD PROGRESS. NO MORE THAN FLURRIES OR
AN ISOLD SHSN ARE ANTICIPATED WITH THIS SYSTEM DURING THE MRNG.

TEMPS WERE FORECAST ABOUT 5 DEGREES UNDR THE AVERAGES USING
TWEAKED NAM GUIDANCE.

&&

.SHORT TERM /TONIGHT THROUGH SUNDAY/...
A GENERALLY DRY AND BELOW NORMAL PERIOD WILL PERSIST ACROSS THE
AREA HEADING INTO THE WEEKEND. DECENT MODEL AGREEMENT EXISTS ON AT
LEAST SOME CLEARING WITH LITTLE CHANCE OF PRECIPITATION UNTIL
ROUGHLY SATURDAY NIGHT/SUNDAY. AT THAT TIME...THE MODELS TRACK A
DUET OF WAVES NEAR THE AREA...FIRST FROM THE SOUTHERN
STREAM...THEN A MORE CLIPPERESQUE TYPE MID-LEVEL SYSTEM THAT DROPS
SOUTHEASTWARD FROM THE CANADIAN PRAIRIE PROVINCES. DUE TO THEIR
CONTINENTAL ORIGINS...NEITHER OF THESE LOOK TO BE PARTICULARLY
MOISTURE-LADEN...SO POPS WERE KEPT TO THE CHANCE CATEGORY FOR THE
MOMENT. HOWEVER THROUGHOUT THE PERIOD...THERMAL PROFILES FROM THE
CONSENSUS FAVOR DEEP ENOUGH COLD AIR TO SUPPORT SNOW THROUGHOUT
THEIR PASSAGE.

WHILE TEMPERATURES REMAIN BELOW NORMAL...THEY DO MODERATE FAIRLY
SIGNIFICANTLY TOWARD THE MID 30S BY THE END OF THE WEEKEND. THIS
WILL BE A BRIEF SEGUE TO MUCH MORE ABRUPT WARMING BY NEXT WEEK.
FRIES

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
BLEND OF RECENT MEDIUM RANGE MODELS SHOW LINGERING POST SYSTEM
CLOUDS ACROSS THE UPPER OHIO VALLEY INTO MONDAY. ENSUING HIGH
PRESSURE WILL PROMOTE A DRY PERIOD INTO MID WEEK.

JUDGING FROM RECENT GFS AND ECMWF MOS...EXPECT TEMPERATURES TO BE
NEAR SEASONABLE LEVELS.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...

STRATOCU CLOUD DECK WILL PROVIDE MVFR RESTRICTIONS AT ALL PORTS
THROUGH AT LEAST DAWN. WAA WILL BEGIN IN ERNEST AFTER DAWN...ERODING
THE CLOUD FROM WEST TO EAST DURING THE MORNING HOURS. THIS WILL
RETURN MOST PORTS TO VFR. AS PER USUAL...THE COLD AIR WILL GET HUNG
UP ACROSS THE NORTH...KEEPING FKL AND DUJ IN MVFR.

NAM MODEL PROFILES SHOW VERTICAL MIXING WILL CAUSE SURFACE
WINDS...FROM THE SOUTHWEST THIS AFTERNOON...TO INCREASE TO 10 KTS
WITH GUSTS TO ABOUT 20 KTS. WINDS CAN BE A TAD MORE WESTERLY TONIGHT
AND LESS GUSTY. WINDS FRIDAY CAN AGAIN BE SOUTHWEST AT 10 KTS WITH
GUSTS TO 20 KTS.

.OUTLOOK.../SATURDAY THROUGH TUESDAY/...
VFR UNTIL POSSIBLE RESTRICTIONS SATURDAY NIGHT AND SUNDAY AS A
WEAK COLD FRONT MOVES ACROSS THE GREAT LAKES.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

15/22






AREA FORECAST DISCUSSION

NWS HASTINGS NE

 1121 PM CST THU JAN 3 2013

.AVIATION.../06Z GRI TAF THROUGH 06Z FRIDAY NIGHT/

VFR SKC WITH SW WINDS AVERAGING 8 KTS THRU THE ENTIRE TAF PERIOD.
CONFIDENCE HIGH ALL ELEMENTS: CIG/VSBY/WX/WIND.

&&

.PREV DISCUSSION... /ISSUED 949 PM CST THU JAN 3 2013/

UPDATE...GOOD RADIATIONAL CONDITIONS HAVE SET UP TONIGHT AND
VSBYS ARE BEGINNING TO FALL IN OUR SOUTH/SOUTHEAST ZONES WHERE
AFTN TEMPS WERE NEAR OR JUST ABOVE FREEZING. HAVE EXPANDED AREA
FOR PATCHY FOG DEVELOPMENT AND INCLUDED POTENTIAL FOR VSBYS
BELOW ONE MILE. WILL CONTINUE TO MONITOR VSBYS/FOG TREND THRU THE
NIGHT.

PREV DISCUSSION... /ISSUED 333 PM CST THU JAN 3 2013/

SHORT TERM...THROUGH 00Z SATURDAY. MORNING UPPER AIR ANALYSIS
INDICATES A POSITIVELY TILTED LONGWAVE TOUGH EXTENDING FROM THE
GREAT LAKES REGION INTO THE SOUTHWESTERN CONUS...WITH RIDGING OVER
MUCH OF THE WESTERN CONUS AND QUASI-ZONAL FLOW ACROSS THE EAST.
MID AND UPPER LEVEL JET ENERGY EXTENDS FROM THE SOUTHERN
PLAINS...EAST/NORTHEAST INTO THE MID-ATLANTIC. TROPOSPHERIC FLOW
OVER OUR AREA IS NOT OVERLY IMPRESSIVE AS A RESULT...MAXING OUT AT
AROUND 50KTS NEAR 350MB PER 12Z RAP ANALYSIS SOUNDING DATA FOR
KGRI. WATER VAPOR IMAGERY INDICATES INCREASED VALUES OF MID LEVEL
MOISTURE OVER PORTIONS OF THE SOUTHEASTERN CONUS AHEAD OF THE MID
LEVEL TROUGH AXIS...HOWEVER MID LEVEL MOISTURE FARTHER
NORTHWEST...OVER THE CENTRAL PLAINS...REMAINS FAIRLY MEAGER. AT
THE SURFACE A RIDGE OF HIGH PRESSURE IS NOTED EXTENDING FROM NORTH
TEXAS...NORTHEAST INTO EASTERN KANSAS. AS A RESULT...THE LOW LEVEL
WIND FIELD ACROSS OUR AREA REMAINS FROM THE WEST/SOUTHWEST BUT IS
VERY LIGHT.

GUIDANCE FROM THE NAM...OPERATIONAL GFS AND EC SUGGEST THE MID
LEVEL TROUGH...CURRENTLY MOVING OVER CENTRAL PORTIONS OF THE
CONUS...WILL DEEPEN INTO A CLOSED LOW OVER THE SOUTHERN PLAINS
TONIGHT INTO TOMORROW. DESPITE THIS DEEPENING MID LEVEL LOW...ANY
OMEGA IN ASSOCIATION WITH THIS SYSTEM IS EXPECTED TO REMAIN OVER
THE SOUTHERN PLAINS...WITH DRY CONDITIONS EXPECTED OVER OUR AREA
TONIGHT AND TOMORROW.

CLEAR SKIES AND 2-6 INCHES OF SNOWPACK ACROSS OUR AREA SHOULD
PROMOTE STRONG RADIATIONAL COOLING TONIGHT...WITH 25-30 DEGREE
DROP OFFS NOT OUT OF THE QUESTION FOR MANY LOCATIONS ACROSS THE
CWA. OVERNIGHT LOWS IN THE SINGLE DIGITS ABOVE ZERO ARE FORECAST
FOR MOST LOCATIONS AS ACROSS THE AREA AS A RESULT. AN INCREASING
SOUTHWESTERLY LOW LEVEL WIND FIELD SHOULD PROMOTE SUBTLE LOW LEVEL
WARM AIR ADVECTION DURING THE DAY FRIDAY...WITH 30-35 DEGREE RISES
CURRENTLY FORECAST. THIS PRESENTS FRIDAY AFTERNOON HIGHS GENERALLY
IN THE 30S.

FINALLY...WITH STRONG RADIATIONAL COOLING EXPECTED TONIGHT AND LOW
LEVEL DEWPOINTS LINGERING IN THE SINGLE DIGITS ABOVE ZERO...NEAR-
SURFACE DEWPOINT DEPRESSIONS NEAR ZERO WILL LIKELY BE REALIZED.
ALTHOUGH DRIER LOW LEVEL AIR WILL BE ADVECTING IN FROM EASTERN
COLORADO AND WESTERN KANSAS...IT APPEARS THE STRONG RADIATIONAL
COOLING...WORKING IN CONCERT WITH A LIGHT LOW LEVEL WIND
FIELD...COULD BE CONDUCIVE FOR PATCHY FOG DEVELOPMENT. WENT AHEAD
WITH SUCH WORDING IN THE FORECAST...PRIMARILY ACROSS OUR
SOUTHEASTERN CWA WHICH IS WHERE LOW LEVEL MOISTURE IS EXPECTED TO
BE THE HIGHEST AND THE LOW LEVEL WIND FIELD IS EXPECTED TO BE THE
WEAKEST.

LONG TERM...FRIDAY NIGHT THROUGH THURSDAY. MAIN FORECAST CONCERNS
WILL BE CHANCE FOR PRECIPITATION WEDNESDAY AND WEDNESDAY NIGHT AND
TEMPERATURES THROUGH THE PERIOD.

A COLD FRONT IS EXPECTED TO MOVE THROUGH THE AREA FRIDAY NIGHT.
DESPITE THE COLD FRONT THE TEMPERATURES FRIDAY NIGHT WILL BE A FEW
DEGREES WARMER THAN THURSDAY NIGHT. THERE IS WARMER AIR ACROSS THE
REGION AND THE COLDER AIR DOES NOT MOVE INTO THE REGION UNTIL ON
SATURDAY. EVEN THIS IS NOT MUCH COLDER AND TEMPERATURES WILL BE
ABOUT THE SAME AS ON FRIDAY. IN ADDITION THERE IS A WEAK UPPER
LEVEL WAVE THAT MOVES INTO THE AREA ON SATURDAY AND BRINGS A FEW
CLOUDS TO THE REGION.

SATURDAY NIGHT INTO SUNDAY AN UPPER LEVEL RIDGE MOVES INTO THE
AREA AND WARM ADVECTION STARTS UP ACROSS THE AREA. WINDS TURN TO
THE SOUTH/SOUTHWEST AND INCREASE. ALL OF THIS SHOULD SHOW UP IN
TEMPERATURES WARMING A BIT ON SUNDAY.

MODELS START TO DIVERGE GREATLY NEXT WEEK. THE GFS AND CANADIAN
BOTH OPEN THE WAVE SOME AND MOVE IT THROUGH MONDAY AND TUESDAY.
THE ECMWF CONTINUES TO KEEP A STRONG UPPER LEVEL LOW THAT MOVES
FROM THE FOUR CORNERS REGION TO THE SOUTHERN PLAINS. THE ECMWF HAS
MAINTAINED SOME RUN TO RUN CONSISTENCY WHILE THE OTHERS HAVE MADE
SOME CHANGES IN THE LAST RUN. FOR NOW WILL CONTINUE TO HAVE THE
PRECIPITATION ON WEDNESDAY AND WEDNESDAY NIGHT WHICH IS MORE
SIMILAR TO THE ECMWF. THE NEXT QUESTION WILL BE PRECIPITATION
TYPE. IN ADDITION TO THE TIMING CHANGE THAT THE GFS
HAS...TEMPERATURES ARE MUCH COLDER...WHICH IS DIFFERENT THAN
PREVIOUS RUNS. HAVE CONTINUED THE WARMER TEMPERATURES AND
THEREFORE WILL KEEP RAIN IN THE FORECAST FOR WEDNESDAY. AS THE
TEMPERATURES COOL OFF WEDNESDAY NIGHT THERE WILL BE SOME SNOW
MIXED INTO THE RAIN. BY THURSDAY...THE UPPER LEVEL LOW HAS MOVED
OFF TO THE EAST AND THEREFORE EXPECT DRY CONDITIONS.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

AVIATION...HALBLAUB







YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT

WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML.

 









AREA FORECAST DISCUSSION

NWS MOUNT HOLLY NJ

 556 AM EST FRI JAN 4 2013

.SYNOPSIS...
HIGH PRESSURE BUILDS TO OUR SOUTH THROUGH SATURDAY, WHILE A WEAK
BACKDOOR COLD FRONT APPROACHES THE AREA FROM THE NORTH SATURDAY, BUT
LIKELY DOES NOT MAKE IT ACROSS THE AREA. AN AREA OF LOW PRESSURE
MOVES OUT OF THE GREAT LAKES REGION AND TOWARD OUR AREA SUNDAY,
BRINGING A WEAK FRONTAL BOUNDARY WITH IT. HIGH PRESSURE REINFORCES
ITSELF ACROSS THE EAST COAST EARLY NEXT WEEK, BEFORE PUSHING
OFFSHORE BY THE MIDDLE OF THE WEEK. ANOTHER LOW PRESSURE AND
ASSOCIATED FRONTAL BOUNDARY COULD AFFECT THE AREA DURING THE MIDDLE
TO LATTER PART OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE LOW LEVEL CLOUD SURGE HAS JUST ABOUT COMPLETED THE TRIP TO THE
NEW JERSEY SHORE...SO HOW THE CLOUD COVER CHANGES WITH TIME WILL
BE THE FORECAST PROBLEM OF THE DAY. THERE ARE SOME BREAKS IN THE
CLOUDS STARTING TO SHOW UP IN THE LEHIGH VALLEY...AND THE LATEST
RAP MODEL SUGGESTS THAT THIS HOLE WILL OPEN UP AND ALLOW MUCH OF
THE AREA TO BREAK OUT THIS MORNING.

HOWEVER...THE LATEST RAP SUGGESTED THIS WOULD OCCUR STARTING LAST
HOUR...SO JUST HOW THIS BREAKS UP MAY HAVE MORE TO DO WITH TERRAIN
(DOWNSLOPING) THAN ANY OTHER PROCESS. THE BREAKS SHOULD CONTINUE
ACROSS SOUTHEAST PENNSYLVANIA...NORTHERN DELAWARE THIS MORNING...
AS THEY WORK INTO CENTRAL AND SOUTHERN NEW JERSEY. THE FEEBLE
EARLY JANUARY SUN PROBABLY DOES NOT HELP MATTERS...AND MOST OF THE
CLEARING WILL HAVE TO OCCUR WITH MIXING DRIER AIR FROM ABOVE. THIS
PROBABLY DOES NOT OCCUR UNTIL MID TO LATE MORNING.

FOR THE SOUTHERN POCONOS AND NORTHWEST NEW JERSEY...THE PROCESS
COULD TAKE A LITTLE LONGER...BUT THIS WAS HINTED AT IN OTHER NEAR
TERM MODELS. NOT MUCH CHANGE TO THE SKY FORECAST IS ANTICIPATED
WITH THE UPDATE.

THE RADAR SIGNATURE FOR FLURRIES HAS GOTTEN BETTER OVER THE SOUTHERN
POCONOS AND NORTHWEST NEW JERSEY EARLY THIS MORNING. THIS MAY
NECESSITATE THE INCLUSION OF FLURRIES INTO THE MORNING HOURS AS THE
UPSLOPE FLOW COINCIDES WITH THE DEEPER BOUNDARY LAYER MOISTURE. AS
THE MOISTURE DRIES OUT...THE THREAT FOR FLURRIES SHOULD DIMINISH.

THE CLOUD COVER ACROSS NORTHWEST ZONES WILL CONTINUE TO BE A
FORECAST CHALLENGE TODAY. THE 0000 UTC NAM MAY BE TOO PESSIMISTIC
WITH ITS BOUNDARY LAYER MOISTURE (UNLESS MOISTURE FROM THE LAKES
BECOMES ENTRAINED). IT LOOKS LIKE THE INVERSION BREAKS BY
AFTERNOON...AND SKY COVER SHOULD DIMINISH. ELSEWHERE...MOISTURE MAY
POOL UNDER THE SHALLOWER INVERSION IN PLACE...BUT THIS SHOULD NOT BE
ENOUGH FOR MORE CLOUDINESS THAN PARTLY SUNNY WOULD COVER.

THE PRESSURE GRADIENT INCREASES DURING THE DAY...AS 925 MB WINDS
INCREASE. MODE SOUNDINGS SUGGEST THAT 35 KNOTS OF WIND COULD BE
AVAILABLE AT THE TOP OF THE INVERSION DURING THE AFTERNOON...AND
THIS COULD TRANSLATE TO 35 TO 40 MPH WINDS IN THE TERRAIN.
ELSEWHERE...THE AMOUNT OF MOMENTUM AT THE TOP OF THE INVERSION DOES
NOT APPEAR TO SUPPORT WIND ADVISORY LEVEL GUSTS. NOR DOES THE
PRESSURE RISES THIS AFTERNOON AND EVENING (WHICH MAXIMIZE OVER
UPSTATE NEW YORK AND NEW ENGLAND). THUS...NO WIND HEADLINES ARE
EXPECTED TODAY.

THE MOS BLEND SEEMED TO CAPTURE HIGH TEMPERATURES WELL THURSDAY.
SINCE THE COLUMN IS ABOUT THE SAME WITH REGARD TO TEMPERATURE AS
THURSDAY...HIGHS TODAY SHOULD BE FAIRLY CLOSE. WITH THIS IN MIND...
HIGHS WERE BASED ON THE SLIGHTLY COOLER NAM MOS NUMBERS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
THE WIND MAY BE THE TRICKIEST PART OF THE FORECAST FOR TONIGHT. THE
CORE OF THE 925 MB WINDS SHOULD OCCUR OVER CENTRAL AND SOUTHERN
AREAS BETWEEN 0000 UTC AND 0600 UTC SATURDAY. SHORT TERM MODELS ARE
SHOWING 35 TO 45 KNOTS OF WIND AT THIS LEVEL...WITH THE 0000 UTC NAM
THE STRONGEST OF THE MODEL SPREAD. MODEL SOUNDINGS IN THE
ABOVEMENTIONED AREA SHOW THAT THE MOMENTUM STAYS ABOVE THE
INVERSION...WHICH LOWERS WITH THE LOSS OF DAYTIME HEATING. WHILE IT
IS POSSIBLE THAT THE HIGHER TERRAIN COULD CONTINUE TO SEE WIND GUSTS
OVER 35 MPH TONIGHT....ELSEWHERE GUSTS SHOULD DIMINISH IN THE
EVENING.

THE BOUNDARY LAYER MOISTURE COULD INCREASE AGAIN ACROSS NORTHERN
ZONES...AS SHORT TERM MODELS ARE SHOWING THIS TREND. MAINLY CLEAR
SKIES ARE EXPECTED ELSEWHERE...AS THE MID LEVEL FLOW QUICKLY BECOMES
ZONAL. THERE COULD BE ENOUGH GRADIENT TONIGHT TO MITIGATE THE
POTENTIAL FOR RADIATIONAL COOLING...ESPECIALLY IN URBAN AREA AND OF
COURSE THE HIGHER TERRAIN. WITH THIS IN MIND...LOWS WERE GENERALLY
BASED ON THE MOS BLEND.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
A WEAK BACKDOOR COLD FRONT IS EXPECTED TO APPROACH THE AREA FROM THE
NORTH ON SATURDAY, BUT WILL LIKELY NOT MAKE IT ALL THE WAY INTO OUR
AREA AS HIGH PRESSURE BUILDS TO OUR SOUTH. WITH SLIGHT RIDGING ALOFT
ACROSS THE AREA SATURDAY AND HIGH PRESSURE AT THE SURFACE TO OUR
SOUTH, WE EXPECT SATURDAY TO BE PRECIPITATION FREE. AS WE MOVE
INTO SATURDAY NIGHT, MODELS CONTINUE TO INDICATE A SHORTWAVE
APPROACHING FROM THE SOUTHWEST. THERE IS SOME MOISTURE ASSOCIATE
WITH THE SHORT WAVE, SO WE COULD HAVE SOME SHOWER ACTIVITY MOVE ACROSS
THE AREA. TEMPERATURES SHOULD BE COLD ENOUGH FOR ANY PRECIPITATION
TO FALL AS SNOW. QPF AMOUNTS ARE GENERALLY LIGHT, SO WE ARE NOT
ANTICIPATING SIGNIFICANT ACCUMULATIONS.

ON SUNDAY, AN AREA OF LOW PRESSURE IS EXPECTED TO MOVE OUT OF THE
GREAT LAKES AND INTO NEW ENGLAND WHILE A SHORT WAVE MOVES THROUGH
THE AREA. THE BEST CHANCE OF ANY SHOWER ACTIVITY IS ACROSS OUR
NORTHWESTERN ZONES WHERE THE HIGHEST MOISTURE CONTENT IS
AVAILABLE. ANOTHER SHORT WAVE IS EXPECTED OVERNIGHT SUNDAY WHICH
COULD HELP LEAD TO ADDITIONAL SHOWER ACTIVITY, MAINLY ACROSS THE
NORTHERN HALF OF THE AREA. TEMPERATURES SUNDAY ARE EXPECTED TO RISE
ABOVE NORMAL AS A WARMING TREND BEGINS.

HIGH PRESSURE IS EXPECTED TO BUILD ACROSS THE EAST COAST MONDAY INTO
TUESDAY, WHILE RIDGING ALOFT TAKES PLACE AS WELL. THIS WILL ALLOW
TEMPERATURES TO REMAIN ABOVE NORMAL AND KEEP THE WEATHER DRY FOR THE
EARLY PART OF THE WEEK.

MODEL GUIDANCE BEGINS TO DIVERGE BY MID WEEK IN REGARDS TO THE NEXT
STORM SYSTEM. THE GFS IS THE FASTEST WITH THE NEXT STORM SYSTEM,
BRINGING IT INTO THE AREA AS EARLY AS WEDNESDAY AFTERNOON/EVENING.
THE ECMWF IS THE SLOWEST BRINGING THE SYSTEM INTO THE AREA THURSDAY
AFTERNOON/EVENING. THE CANADIAN WAS NEARLY RIGHT BETWEEN THE TWO AT
THE END OF ITS FORECAST CYCLE, SO WE TOOK A COMPROMISE BETWEEN THE GFS
AND ECMWF, BUT ONLY INTRODUCED A SLIGHT CHANCE OF PRECIP WEDNESDAY
NIGHT INTO THURSDAY. FOR MOST OF THE AREA, TEMPERATURES ARE
EXPECTED TO BE WARM ENOUGH TO KEEP ANY PRECIPITATION LIQUID, BUT
AREA FURTHER NORTH AND WEST COULD SEE SOME WINTRY PRECIP. AS WE
GET CLOSER, DETAILS WILL BECOME BETTER DEFINED. TEMPERATURES FOR
THE MIDDLE TO THE END OF THE WEEK ARE EXPECTED TO REMAIN ABOVE
NORMAL, WITH SOME AREA POSSIBLY RISING 1O TO 15 DEGREES ABOVE
NORMAL.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE VFR CEILINGS (WITH BASES NEAR 4000 FEET) PROBABLY REMAIN IN
PLACE THROUGH 1500 UTC FOR MOST PLACES OUTSIDE OF THE TERRAIN
(WHERE IS LASTS EVEN LONGER). THE UPDATED TERMINAL FORECASTS WILL
INDICATE THIS...AND CONDITIONS SHOULD IMPROVE AFTER 1500 UTC.
RECENT AMDAR SOUNDINGS SUGGEST THAT THE CEILINGS WILL REMAIN
VFR...WITH JUST A LOW PROBABILITY OF MVFR CEILINGS THROUGH 1500
UTC.

AFTER THE CLOUDS BREAK LATER THIS MORNING...SCATTERED CLOUDS ARE
EXPECTED TODAY...WITH BASES CLOSE TO 3500 FEET. THERE IS A LOW
PROBABILITY THAT KABE AND KRDG COULD SEE CEILINGS NEAR 3000 FEET
FOR A TIME BETWEEN 1600 AND 2100 UTC. HOWEVER...THE PROBABILITY IS
NOT HIGH ENOUGH TO INCLUDE IN THE UPDATED FORECASTS. WEST WINDS
WILL BECOME GUSTY AFTER 1400 OR 1500 UTC...WITH MOST LOCATIONS
SEEING GUSTS REACH 24 TO 27 KNOTS THROUGH SUNSET.

VFR CONDITIONS ARE EXPECTED TONIGHT. THE SCATTERED CLOUDS NEAR 3500
FEET SHOULD DISSIPATE DURING THE EVENING. THE GUSTINESS SHOULD DROP
OFF BY 0100 UTC SATURDAY...THROUGH THE KPHL METRO AIRPORTS COULD
HANG ONTO THE GUSTINESS A BIT LONGER.

OUTLOOK...
SATURDAY-TUESDAY...MAINLY VFR. SNOW SHOWERS/FLURRIES POSSIBLE
SATURDAY NIGHT-SUNDAY NIGHT...ESPECIALLY NORTH AND WEST OF THE
ILG-PHL-PNE-TTN TAFS.

&&

.MARINE...
THE PRESSURE GRADIENT IS SUPPORTING SMALL CRAFT WIND GUSTS ALONG
SOME OCEAN LOCATIONS...BUT NOT OTHERS YET. THE GRADIENT HAS NOT YET
TIGHTENED ENOUGH TO SUPPORT SMALL CRAFT WINDS ON THE UPPER DELAWARE
BAY...AND IT IS GETTING CLOSE ON THE LOWER BAY. AS THE PRESSURE
GRADIENT TIGHTENS DURING THE EARLY MORNING HOURS...ALL WATERS SHOULD
BE NEAR OR ABOVE SMALL CRAFT WITH REGARD TO WIND GUSTS.

THE GRADIENT LOOKS TO SUPPORT SMALL CRAFT WINDS TODAY ON ALL
WATERS...THOUGH IT MAY BE MORE SPOTTY ON THE UPPER DELAWARE BAY. IT
IS POSSIBLE THAT A WEAKNESS IN THE GRADIENT EARLY THIS AFTERNOON
COULD ALLOW GUSTS ON DELAWARE BAY TO DROP BELOW SMALL CRAFT LEVELS.
THIS SHOULD BE TEMPORARY AND LITTLE CHANGE IN FORECAST PHILOSOPHY
FOR TODAY.

SHORT TERM MODELS ARE SHOWING WEST TO NORTHWEST WINDS AT 925 MB
INCREASING TO NEAR 40 KNOTS BEFORE 0000 UTC SATURDAY. MODEL
SOUNDINGS SUGGEST THAT THE MOMENTUM STAYS ABOVE THE INVERSION OVER
THE WATERS INTO THE EARLY EVENING HOURS. WHILE THERE COULD BE SOME
GUSTS TO NEAR 30 KNOTS TOWARD EVENING...GALE FORCE WINDS GUSTS DO
NOT LOOK LIKELY TODAY.

THE FORECAST PROBLEM FOR TODAY IS WHETHER THERE WILL BE ENOUGH GALE
FORCE WIND GUSTS TO JUSTIFY A GALE WARNING. THE CORE OF THE
STRONGEST WEST WINDS AT 925 MB CROSS THE CENTRAL WATERS BETWEEN 0300
UTC AND 0900 UTC SATURDAY...MAXIMIZING AROUND 0600 UTC. TYPICALLY 45
KNOTS AT 925 MB WOULD SUGGEST GALE FORCE GUSTS. MODEL SOUNDINGS
SUGGEST THAT THE CORE OF THE STRONGEST WINDS REMAINING ABOVE THE
INVERSION FOR THE CENTRAL AND NORTHERN OCEAN WATERS.

WHILE IT WILL BE CLOSE...WE WILL HOLD OFF ON A GALE WARNING FOR NOW.
IF THE 0600 UTC MODEL SUITE IS STRONGER WITH THE CORE OF THE WINDS
(AND MODEL SOUNDINGS ARE MORE GENEROUS WITH MOMENTUM TRANSFER)...IT
IS POSSIBLE A GALE WARNING COULD BE NEEDED LATER THIS MORNING. THE
MOST LIKELY CANDIDATES FOR A GALE WARNING WOULD BE THE NORTHERNMOST
OCEAN ZONE (OR TWO).

IN ANY EVENT...THE GALE THREAT SHOULD DIMINISH ACROSS THE NORTHERN
OCEAN AFTER 0900 UTC. ELSEWHERE...STRONG SMALL CRAFT WINDS ARE
EXPECTED THROUGH THE OVERNIGHT.

OUTLOOK...
SMALL CRAFT ADVISORY CONDITIONS COULD LAST THROUGH MIDDAY SATURDAY,
SO THE ADVISORY WAS EXTENDED UNTIL NOON SATURDAY. WINDS ARE EXPECTED
TO REMAIN BELOW ADVISORY LEVELS THE REST OF THE DAY SATURDAY INTO
SATURDAY NIGHT AS HIGH PRESSURE BUILDS TO OUR SOUTH. AS LOW PRESSURE
MOVES OUT OF THE GREAT LAKES INTO NEW ENGLAND SUNDAY, A COLD FRONT
WILL SWEEP THROUGH OUR AREA. WINDS BEHIND THIS SYSTEM COULD REACH
ADVISORY LEVELS SUNDAY NIGHT INTO EARLY MONDAY. WINDS ARE
EXPECTED TO DROP BACK BELOW ADVISORY LEVELS AS HIGH PRESSURE
REINFORCES ITSELF ACROSS THE EAST COAST LATE MONDAY INTO TUESDAY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL NOON EST SATURDAY FOR ANZ430-431-
     450>455.

&&

$$

SYNOPSIS...ROBERTSON
NEAR TERM...HAYES
SHORT TERM...HAYES
LONG TERM...ROBERTSON
AVIATION...HAYES/ROBERTSON
MARINE...HAYES/ROBERTSON







AREA FORECAST DISCUSSION...UPDATED

NWS COLUMBIA SC

 1020 AM EST FRI JAN 4 2013

.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION TONIGHT INTO SATURDAY. A
FRONTAL SYSTEM WILL PROVIDE A CHANCE OF RAIN SATURDAY NIGHT AND
SUNDAY. FAIR WEATHER EXPECTED EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST VISIBLE IMAGERY SHOWING THE EXPANSIVE FOG ACROSS THE
EASTERN MIDLANDS AND PARTS OF THE CSRA. FOG HAS BEGUN TO DISSIPATE
IN THE COLUMBIA AREA AND SHOULD CONTINUE TO DISSIPATE ELSEWHERE
THROUGH 11-11:30AM AS RAP INITIALIZED AND FORECAST SOUNDINGS SHOW
THE MOISTURE IS VERY SHALLOW. TEMPERATURES HAVE BEEN SLOW TO RISE
THIS MORNING DUE TO THE BLANKET OF FOG BUT THEY SHOULD REBOUND
QUICKLY WITH INSOLATION LATE THIS MORNING. FORECAST MAX
TEMPERATURES LOOK REASONABLE GIVEN LATEST THICKNESS ANALYSIS AND
LOCAL TEMPERATURE SCHEME. WILL ADJUST HOURLY GRIDDED FORECAST TO
ACCOUNT FOR LATEST TEMPERATURE AND FOG TRENDS. THERE COULD BE A
BIT MORE HIGH CLOUDS ESPECIALLY ACROSS THE EASTERN MIDLANDS THIS
AFTERNOON WITH SOUTHWESTERLY FLOW ALOFT.

OVERNIGHT...STRONG RADIATIONAL COOLING CONDITIONS ARE EXPECTED
WITH HIGH PRESSURE OVER THE AREA AND TEMPERATURES SHOULD FALL INTO
THE UPPER 20S TO LOWER 30S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
FAIR WEATHER EXPECTED THROUGH SATURDAY...AS SURFACE HIGH PRESSURE
BUILDS INTO THE REGION WITH A DRY ATMOSPHERE IN PLACE. AN UPPER
TROUGH WILL LIFT NE OUT OF THE SOUTHERN PLAINS AND LOWER MISS
VALLEY SATURDAY NIGHT BRINGING INCREASING CLOUDINESS AND THE
POSSIBILITY OF SHOWER ACTIVITY INTO OUR REGION LATE SATURDAY
NIGHT.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
NO SIGNIFICANT CHANGES WERE MADE TO THE FORECAST FOR THIS TIME
PERIOD. PREVIOUS DISCUSSION FOLLOWS...

THERE IS CONSIDERABLE UNCERTAINTY NOTED IN THE ENSEMBLE POP
GUIDANCE THROUGH MONDAY WITH THE OPERATIONAL GFS QUITE DRY.
THERE IS UNCERTAINTY LATE IN THE PERIOD AS ANOTHER UPPER LOW MOVES
SLOWLY NORTHEAST.

THE UPPER RIDGE WILL SHIFT EAST INTO THE CENTRAL CONUS SUN/MON.
A WEAK SURFACE FRONT WILL MOVE THROUGH THE REGION SUNDAY.
FORECASTED CHANCE POPS SUNDAY AND WITH CLOUDINESS MOST OF THE DAY
PREFER THE COOLER TEMPERATURE GUIDANCE. CONFIDENCE LIMITED AT THIS
TIME. SURFACE HIGH PRESSURE WILL BUILD INTO THE AREA BEHIND THE
FRONT EARLY TO MID NEXT WEEK. THE MODELS KEEP THE MAIN UPPER FLOW
WELL TO THE NORTH...WITH A CUT-OFF LOW DEVELOPING OVER THE SW
CONUS....AND A SW UPPER FLOW AND HEIGHT RISES OVER OUR REGION.
THIS WILL ALLOW THE AIR MASS TO MODIFY EARLY NEXT WEEK WITH HIGH
TEMPERATURES INCREASING TO ABOVE NORMAL. THERE IS UNCERTAINTY
AGAIN LATE IN THE PERIOD. THE GFS IS MUCH FASTER THAN THE ECMWF
EJECTING AN UPPER-LEVEL LOW NORTHEAST FROM THE DESERT SOUTHWEST.
THE GFS IS MUCH WETTER MIDWEEK. PREFER A SLOWER SOLUTION BECAUSE
AN UPSTREAM KICKER APPEARS TO BE LACKING SO KEPT A DRY FORECAST
UNTIL VERY LATE IN THE PERIOD.

&&

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
MORNING FOG IS DISSIPATING AND LIFTING AND VFR CONDITIONS ARE
EXPECTED ALL TERMINALS AFTER 16Z...OGB MAY LINGER MVFR THROUGH
17Z. LIGHT WESTERLY WINDS EXPECTED THIS AFTERNOON UNDER MOSTLY
SUNNY SKIES.

EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE SATURDAY NIGHT AND
SUNDAY WITH FRONTAL SYSTEM IN THE VICINITY.

&&

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

$$







AREA FORECAST DISCUSSION

NWS CHARLESTON SC

 929 AM EST FRI JAN 4 2013

.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE REGION THROUGH SATURDAY. A WARM
FRONT WILL LIFT TOWARD THE REGION AND STALL JUST SOUTH AND EAST OF
THE AREA SATURDAY NIGHT. A WAVE OF LOW PRESSURE WILL PASS OFFSHORE
ALONG THE FRONT ON SUNDAY. HIGH PRESSURE WILL THEN BUILD INTO THE
REGION AND PERSIST THROUGH AT LEAST THE BEGINNING OF NEXT WEEK
WITH ANOTHER COLD FRONT POSSIBLE FOR THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SATELLITE AND SURFACE OBSERVATIONS SHOW FOG...LOCALLY
DENSE...LINGERS IN A STRIP FROM ROUGHLY STATESBORO NORTHEAST
THROUGH WALTERBORO AND MONCKS CORNER. THE FOG LAYER LOOKS PRETTY
THIN PER RAP FORECAST SOUNDINGS AND THE 05/12Z CHS RAOB...SO
WOULD EXPECT THE FOG TO BREAKUP PRETTY QUICKLY ONCE THE MORNING
INVERSION MIXES OUT. EXTENDED THE SPECIAL WEATHER STATEMENT
THROUGH 1030 PM TO ADDRESS THE SITUATION.

OTHERWISE...THE REMAINDER OF THE FORECAST IS ON TRACK. OPTED TO
NUDGE SKY COVER INTO THE PARTLY CLOUDY CATEGORY AS CIRRUS
ASSOCIATED WITH THE SUBTROPICAL JET IS POISED TO MOVE IN FROM THE
SOUTHWEST.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
TONIGHT...A SHORT WAVE TROUGH WILL SKIRT BY TO THE NORTH AS
SURFACE HIGH PRESSURE BUILDS INTO THE REGION FROM THE TENNESSEE
VALLEY. A VERY DRY AIRMASS...CLEAR SKIES AND LIGHT WINDS WILL
PROMOTE GOOD RADIATIONAL COOLING WITH LOWS IN THE LOWER 30S IN
WELL SHELTERED/LOW-LYING INLAND LOCATIONS AND THE MID 30S
ELSEWHERE AWAY FROM WARMER COASTAL AREAS.

HIGH PRESSURE TO START SATURDAY WILL WEAKEN THROUGH THE DAY BUT
SHOULD KEEP THINGS DRY AS THE DEEPER MOISTURE REMAINS SOUTH AND WEST
OF THE AREA. HOWEVER...RAIN CHANCES WILL INCREASE SLIGHTLY SATURDAY
NIGHT INTO SUNDAY...MAINLY ACROSS SOUTHEAST GEORGIA...AS MOISTURE
INCREASES AND AN UPPER JET STRENGTHENS NORTH OF THE AREA OVER THE
MID ATLANTIC REGION. HIGH PRESSURE WILL THEN BUILD FROM THE
NORTHWEST LATER SUNDAY THROUGH MONDAY WITH DRY WEATHER PREVAILING.
TEMPERATURES LOOK TO BE RELATIVELY CLOSE TO NORMAL FOR THIS TIME OF
YEAR...AROUND 60 FOR HIGHS AND AROUND 40 FOR LOWS /EXCEPT SUNDAY
MORNING WHEN LOWER TO MID 40S ARE EXPECTED DUE TO THE CLOUDS/RAIN/.

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
THE FORECAST BECOMES MUCH MORE UNCERTAIN THIS PERIOD...MAINLY DUE TO
THE TIMING OF A COLD FRONT FOR MID WEEK. DECIDED TO FOLLOW THE
SLOWER ECMWF/CMC/HPC GUIDANCE WHICH INDICATES MOSTLY DRY CONDITIONS
INTO WEDNESDAY WITH HIGH PRESSURE PREVAILING. WILL CARRY SOME LOW
RAIN CHANCES THROUGH THURSDAY NIGHT. THE MAIN CONCERN THIS PERIOD
WILL BE THE POTENTIAL FOR SOME STRONG TO POSSIBLY SEVERE STORMS
WEDNESDAY AS THE FASTER GFS SOLUTION INDICATES. TEMPERATURES SHOULD
BE NEAR TO ABOVE NORMAL.

&&

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
KCHS...FOG IS EXPECTED TO REDUCE VISIBILITIES TO MVFR LEVELS
THROUGH ABOUT 14Z...WITH TEMPORARY REDUCTIONS IN VISIBILITIES
AND/OR CEILINGS TO IFR OR LOWER LEVELS POSSIBLE. VFR CONDITIONS
ARE THEN EXPECTED TO PREVAIL THROUGH 12Z SATURDAY.

KSAV...LOW STRATUS WITH MVFR CEILINGS WILL PERSIST THROUGH ABOUT
15Z. IF THE CLOUDS CLEAR ANY SOONER...THEN PATCHY FOG COULD RESULT
IN SOME REDUCED VISIBILITIES AT THE TERMINAL. VFR CONDITIONS ARE
THEN EXPECTED TO PREVAIL THROUGH 12Z SATURDAY.

EXTENDED AVIATION OUTLOOK...VFR CONDITIONS WILL PREVAIL THROUGH
SATURDAY. MVFR OR LOWER CONDITIONS MAY DEVELOP SATURDAY NIGHT INTO
SUNDAY DUE TO LOW CEILINGS AND RAIN.

&&

.MARINE...
TODAY AND TONIGHT...A NORTHERLY FLOW WILL PREVAIL OVER THE WATERS
AS HIGH PRESSURE BUILDS INTO THE REGION FROM THE WEST. A TIGHT
SURFACE PRESSURE GRADIENT AND WEAK COLD AIR ADVECTION THIS MORNING
COULD CAUSE WINDS TO SURGE UPWARDS OF 15-20 KT AT TIMES...BUT ONCE
THE GRADIENT WEAKENS LATE THIS MORNING WINDS SHOULD REMAIN AROUND
15 KT OR LESS ACROSS ALL WATERS THROUGH TONIGHT. SEAS WILL BE AS
HIGH AS 3-4 FT IN THE OUTER GEORGIA WATERS AND 2-3 FT IN THE NEAR
SHORE WATERS THIS MORNING...BEFORE SUBSIDING TO 3 FT OR LESS
THROUGHOUT THIS AFTERNOON AND TONIGHT AS WINDS DIMINISH.

SATURDAY THROUGH WEDNESDAY...HIGH PRESSURE WILL SLIDE NORTH OF THE
AREA SATURDAY WITH A WAVE OF LOW PRESSURE DEVELOPING OVER OR NEAR
THE AREA INTO SUNDAY. HIGH PRESSURE WILL THEN RETURN INTO EARLY NEXT
WEEK AS THE LOW PULLS AWAY WITH A COASTAL TROUGH OF LOW PRESSURE
POSSIBLY DEVELOPING. CONDITIONS LOOK TO GO DOWNHILL INTO MONDAY DUE
TO THE ELEVATED NORTH/NORTHEAST FLOW AND SMALL CRAFT ADVISORIES ARE
A GOOD BET AT LEAST BEYOND 20 NM. BEYOND THIS TIME THE FORECAST GETS
A LOT MORE UNCERTAIN DUE TO THE TIMING OF THE NEXT COLD FRONT WHICH
COULD ARRIVE AS EARLY AS WEDNESDAY NIGHT. IF THIS
OCCURS...WINDS/SEAS WILL BE MUCH HIGHER THAN CURRENTLY FORECAST DUE
TO A STRONG SOUTHERLY SURGE AHEAD OF THE FRONT...ESPECIALLY ACROSS
THE WARMER WATERS BEYOND 20 NM FROM SHORE WHERE MIXING WILL BE
GREATER.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

ST






AREA FORECAST DISCUSSION

NWS JACKSON KY

 1019 AM EST FRI JAN 4 2013

.UPDATE...
ISSUED AT 1015 AM EST FRI JAN 4 2013

UPDATED THE FORECAST TO BETTER REFLECT MODEL TRENDS AND CURRENT
CONDITIONS. MAIN ADJUSTMENTS WERE FOR THE CLOUDS MOVING ACROSS THE
AREA AS A POTENT...BUT DRY...UPPER TROUGH MOVES ACROSS THE AREA THIS
AFTERNOON.

UPDATE ISSUED AT 742 AM EST FRI JAN 4 2013

HAVE UPDATED THE GRID DATABASE TO BLEND OBSERVED EARLY MORNING CLOUD
AND TEMPERATURE TRENDS INTO THE AFTERNOON FORECAST.

&&

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 240 AM EST FRI JAN 4 2013

STILL NO SIGNIFICANT SYSTEMS TO CONTEND WITH IN THE SHORT TERM...BUT
THERE ARE A COUPLE OF ANNOYING ITEMS.

THE FIRST OF THESE IS THE LOW CLOUD DECK WHICH HAS BEEN SLOWLY
SINKING SOUTH OVER THE OHIO VALLEY DURING THE NIGHT. THE NAM IS NOT
MUCH HELP...ONCE AGAIN DOING VERY POORLY HANDLING LOW LEVEL MOISTURE.
THE GFS AT LEAST KNEW THAT IT WAS THERE...BUT THE CLOUDS HAVE
PROGRESSED SOUTH DURING THE NIGHT A BIT MORE THAN THE GFS SHOWED. THE
RUC IS PERHAPS PERFORMING THE BEST...BUT IS ONLY AVAILABLE THROUGH
18Z FRIDAY. WILL USE THE RUC THROUGH ITS PERIOD OF AVAILABILITY...AND
FOLLOW UP WITH THE GFS TREND OF DRYING UP THE CLOUDS DURING THE LATE
AFTERNOON AND EARLY EVENING.

RIDGING BUILDING IN AT THE SURFACE AND ALOFT SHOULD BRING MAINLY
CLEAR SKIES TONIGHT INTO SATURDAY MORNING.

AN UPPER LOW CURRENTLY OVER THE SOUTHWEST CONUS IS EXPECTED TO BE
PICKED UP BY AN UPPER LEVEL NORTHERN STREAM TROUGH DROPPING INTO THE
NORTH CENTRAL CONUS ON SATURDAY. AS THE UPPER LOW HEADS NORTHEAST TO
THE OHIO VALLEY...WE WILL SEE MID AND UPPER LEVEL CLOUDS INCREASE.
VIRGA WILL EVENTUALLY WORK TO MOISTEN LOWER LEVELS...AND SOME LIGHT
PRECIP CAN NOT BE RULED OUT LATE SATURDAY OR SATURDAY EVENING.
HOWEVER...ABOUT THE TIME THE LOWER LEVELS MOISTEN...MID/UPPER LEVEL
DRYING IS FORECAST AS THE SYSTEM ALOFT DEPARTS. THIS WILL LEAVE A
NARROW WINDOW OF OPPORTUNITY FOR PRECIP...AND HAVE ONLY USED 20
PERCENT POPS. CONDITIONS LOOK MARGINAL FOR RAIN VERSUS SNOW.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 255 AM EST FRI JAN 4 2013

THE MODELS START OFF IN GOOD AGREEMENT AND REMAIN IN GOOD AGREEMENT
THROUGH TUESDAY. HOWEVER...STILL SIGNIFICANT TIMING ISSUES WITH THE
NEXT WEATHER MAKER TOWARDS THE MIDDLE OF NEXT WEEK...LEADING TO VERY
LOW CONFIDENCE AT THIS TIME.

STARTING OFF THE FORECAST ON SUNDAY...IT LOOKS LIKE A TRANQUIL
PERIOD OF WEATHER IS EXPECTED DURING THE DAY...BUT A FAST MOVING
CLIPPER WILL DROP SOUTHEAST AND PROVIDE A QUICK SHOT FOR SOME
ISOLATED SNOW SHOWERS TOWARDS 00Z MONDAY. MOISTURE REMAINS VERY
WEAK...BUT UPSLOPE FLOW COULD HELP GENERATE THE NEEDED LIFT FOR A
FEW SNOW SHOWERS. NOT ANTICIPATING ANY ACCUMULATIONS AT THIS TIME.
MID LEVEL RIDING WILL SPREAD INTO THE AREA BY DAYBREAK MONDAY...WITH
CLEAR SKIES RETURNING. THIS WILL YIELD ANOTHER COLD START TO THE
DAY...BUT WE SHOULD SEE A NICE RECOVERY UNDER SUNNY SKIES ON MONDAY.
AS THE HIGH PRESSURE RIDGE PUSHES EAST...RETURN FLOW WILL ALLOW FOR
A FAIRLY GOOD WARM UP FOR THE EARLY TO MIDDLE PORTIONS OF NEXT WEEK.
HIGHS TUESDAY...WEDNESDAY...AND THURSDAY COULD PUSH 50 OR EXCEED IT.
HOWEVER...THE BIG QUESTION REMAINS HOW FAST THE NEXT WEATHER SYSTEM
ARRIVES FROM THE DESERT SOUTHWEST. GFS HAS ACTUALLY SPED UP THE
SYSTEM EVEN MORE AND NOW BRINGS A FAIRLY ROBUST SHORTWAVE TROUGH
INTO THE OHIO RIVER VALLEY ON WEDNESDAY. THE 00Z ECMWF REMAINS MUCH
SLOWER WITH THE MAIN SYSTEM NOT ARRIVING UNTIL THURSDAY. THE GFS
ENSEMBLE MEMBERS REMAIN IN CONSIDERABLE DISAGREEMENT...SO PLAN TO
KEEP A BROAD PERIOD OF LOW POPS IN THE FORECAST FROM LATE TUESDAY
NIGHT THROUGH THURSDAY EVENING. WITH THE WARM AIR MASS IN PLACE...AND
NO COLD AIR WRAPPING INTO THIS SYSTEM...PRECIPITATION WILL REMAIN
RAIN.

REGARDLESS OF THE TIMING OF THIS SYSTEM...IT LOOKS LIKE DRIER
WEATHER SHOULD RETURN BY FRIDAY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 606 AM EST FRI JAN 4 2013

A DECK OF CLOUDS IN THE RANGE OF 2500-3500 FEET WILL MOVE OVER THE
NORTHERN AND EASTERN PORTIONS OF THE FORECAST AREA THIS MORNING...AND
THEN THIN OUT TO A SCATTERED LAYER IN THE AFTERNOON. THIS WILL BRING
A PERIOD OF MVFR TO MANY LOCATIONS NORTH OF A LINE FROM SOMERSET TO
PIKEVILLE. WEST WINDS WILL KICK IN DURING THE DAY...ESPECIALLY NEAR
AND NORTH OF INTERSTATE 64...WHERE GUSTS OF 20-25 KNOTS ARE EXPECTED.

WINDS WILL DIE DOWN EARLY THIS EVENING AND SKIES WILL CLEAR...LEAVING
VFR AND LIGHT WINDS THROUGH THE REMAINDER OF THE PERIOD.


&&

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

$$

UPDATE...RAY
SHORT TERM...HAL
LONG TERM....KAS
AVIATION...HAL







AREA FORECAST DISCUSSION...CORRECTED

NWS JACKSON KY

 743 AM EST FRI JAN 4 2013

.UPDATE...
ISSUED AT 742 AM EST FRI JAN 4 2013

HAVE UPDATED THE GRID DATABASE TO BLEND OBSERVED EARLY MORNING CLOUD
AND TEMPERATURE TRENDS INTO THE AFTERNOON FORECAST.

&&

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 240 AM EST FRI JAN 4 2013

STILL NO SIGNIFICANT SYSTEMS TO CONTEND WITH IN THE SHORT TERM...BUT
THERE ARE A COUPLE OF ANNOYING ITEMS.

THE FIRST OF THESE IS THE LOW CLOUD DECK WHICH HAS BEEN SLOWLY
SINKING SOUTH OVER THE OHIO VALLEY DURING THE NIGHT. THE NAM IS NOT
MUCH HELP...ONCE AGAIN DOING VERY POORLY HANDLING LOW LEVEL MOISTURE.
THE GFS AT LEAST KNEW THAT IT WAS THERE...BUT THE CLOUDS HAVE
PROGRESSED SOUTH DURING THE NIGHT A BIT MORE THAN THE GFS SHOWED. THE
RUC IS PERHAPS PERFORMING THE BEST...BUT IS ONLY AVAILABLE THROUGH
18Z FRIDAY. WILL USE THE RUC THROUGH ITS PERIOD OF AVAILABILITY...AND
FOLLOW UP WITH THE GFS TREND OF DRYING UP THE CLOUDS DURING THE LATE
AFTERNOON AND EARLY EVENING.

RIDGING BUILDING IN AT THE SURFACE AND ALOFT SHOULD BRING MAINLY
CLEAR SKIES TONIGHT INTO SATURDAY MORNING.

AN UPPER LOW CURRENTLY OVER THE SOUTHWEST CONUS IS EXPECTED TO BE
PICKED UP BY AN UPPER LEVEL NORTHERN STREAM TROUGH DROPPING INTO THE
NORTH CENTRAL CONUS ON SATURDAY. AS THE UPPER LOW HEADS NORTHEAST TO
THE OHIO VALLEY...WE WILL SEE MID AND UPPER LEVEL CLOUDS INCREASE.
VIRGA WILL EVENTUALLY WORK TO MOISTEN LOWER LEVELS...AND SOME LIGHT
PRECIP CAN NOT BE RULED OUT LATE SATURDAY OR SATURDAY EVENING.
HOWEVER...ABOUT THE TIME THE LOWER LEVELS MOISTEN...MID/UPPER LEVEL
DRYING IS FORECAST AS THE SYSTEM ALOFT DEPARTS. THIS WILL LEAVE A
NARROW WINDOW OF OPPORTUNITY FOR PRECIP...AND HAVE ONLY USED 20
PERCENT POPS. CONDITIONS LOOK MARGINAL FOR RAIN VERSUS SNOW.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 255 AM EST FRI JAN 4 2013

THE MODELS START OFF IN GOOD AGREEMENT AND REMAIN IN GOOD AGREEMENT
THROUGH TUESDAY. HOWEVER...STILL SIGNIFICANT TIMING ISSUES WITH THE
NEXT WEATHER MAKER TOWARDS THE MIDDLE OF NEXT WEEK...LEADING TO VERY
LOW CONFIDENCE AT THIS TIME.

STARTING OFF THE FORECAST ON SUNDAY...IT LOOKS LIKE A TRANQUIL
PERIOD OF WEATHER IS EXPECTED DURING THE DAY...BUT A FAST MOVING
CLIPPER WILL DROP SOUTHEAST AND PROVIDE A QUICK SHOT FOR SOME
ISOLATED SNOW SHOWERS TOWARDS 00Z MONDAY. MOISTURE REMAINS VERY
WEAK...BUT UPSLOPE FLOW COULD HELP GENERATE THE NEEDED LIFT FOR A
FEW SNOW SHOWERS. NOT ANTICIPATING ANY ACCUMULATIONS AT THIS TIME.
MID LEVEL RIDING WILL SPREAD INTO THE AREA BY DAYBREAK MONDAY...WITH
CLEAR SKIES RETURNING. THIS WILL YIELD ANOTHER COLD START TO THE
DAY...BUT WE SHOULD SEE A NICE RECOVERY UNDER SUNNY SKIES ON MONDAY.
AS THE HIGH PRESSURE RIDGE PUSHES EAST...RETURN FLOW WILL ALLOW FOR
A FAIRLY GOOD WARM UP FOR THE EARLY TO MIDDLE PORTIONS OF NEXT WEEK.
HIGHS TUESDAY...WEDNESDAY...AND THURSDAY COULD PUSH 50 OR EXCEED IT.
HOWEVER...THE BIG QUESTION REMAINS HOW FAST THE NEXT WEATHER SYSTEM
ARRIVES FROM THE DESERT SOUTHWEST. GFS HAS ACTUALLY SPED UP THE
SYSTEM EVEN MORE AND NOW BRINGS A FAIRLY ROBUST SHORTWAVE TROUGH
INTO THE OHIO RIVER VALLEY ON WEDNESDAY. THE 00Z ECMWF REMAINS MUCH
SLOWER WITH THE MAIN SYSTEM NOT ARRIVING UNTIL THURSDAY. THE GFS
ENSEMBLE MEMBERS REMAIN IN CONSIDERABLE DISAGREEMENT...SO PLAN TO
KEEP A BROAD PERIOD OF LOW POPS IN THE FORECAST FROM LATE TUESDAY
NIGHT THROUGH THURSDAY EVENING. WITH THE WARM AIR MASS IN PLACE...AND
NO COLD AIR WRAPPING INTO THIS SYSTEM...PRECIPITATION WILL REMAIN
RAIN.

REGARDLESS OF THE TIMING OF THIS SYSTEM...IT LOOKS LIKE DRIER
WEATHER SHOULD RETURN BY FRIDAY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 606 AM EST FRI JAN 4 2013

A DECK OF CLOUDS IN THE RANGE OF 2500-3500 FEET WILL MOVE OVER THE
NORTHERN AND EASTERN PORTIONS OF THE FORECAST AREA THIS MORNING...AND
THEN THIN OUT TO A SCATTERED LAYER IN THE AFTERNOON. THIS WILL BRING
A PERIOD OF MVFR TO MANY LOCATIONS NORTH OF A LINE FROM SOMERSET TO
PIKEVILLE. WEST WINDS WILL KICK IN DURING THE DAY...ESPECIALLY NEAR
AND NORTH OF INTERSTATE 64...WHERE GUSTS OF 20-25 KNOTS ARE EXPECTED.

WINDS WILL DIE DOWN EARLY THIS EVENING AND SKIES WILL CLEAR...LEAVING
VFR AND LIGHT WINDS THROUGH THE REMAINDER OF THE PERIOD.


&&

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

$$

UPDATE...HAL
SHORT TERM...HAL
LONG TERM....KAS
AVIATION...HAL









AREA FORECAST DISCUSSION

NWS JACKSON KY

 742 AM EST FRI JAN 4 2013

.UPDATE...
ISSUED AT 742 AM EST FRI JAN 4 2013

HAVE UPDATED THE GRID DATABASE TO BLEND OBSERVED EARLY MORNING CLOUD
AND TEMPERATURE TRENDS INTO THE AFTERNOON FORECAST.

&&

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 240 AM EST FRI JAN 4 2013

STILL NO SIGNIFICANT SYSTEMS TO CONTEND WITH IN THE SHORT TERM...BUT
THERE AREA A COUPLE OF ANNOYING ITEMS.

THE FIRST OF THESE IS THE LOW CLOUD DECK WHICH HAS BEEN SLOWLY
SINKING SOUTH OVER THE OHIO VALLEY DURING THE NIGHT. THE NAM IS NOT
MUCH HELP...ONCE AGAIN DOING VERY POORLY HANDLING LOW LEVEL MOISTURE.
THE GFS AT LEAST KNEW THAT IT WAS THERE...BUT THE CLOUDS HAVE
PROGRESSED SOUTH DURING THE NIGHT A BIT MORE THAN THE GFS SHOWED. THE
RUC IS PERHAPS PERFORMING THE BEST...BUT IS ONLY AVAILABLE THROUGH
18Z FRIDAY. WILL USE THE RUC THROUGH ITS PERIOD OF AVAILABILITY...AND
FOLLOW UP WITH THE GFS TREND OF DRYING UP THE CLOUDS DURING THE LATE
AFTERNOON AND EARLY EVENING.

RIDGING BUILDING IN AT THE SURFACE AND ALOFT SHOULD BRING MAINLY
CLEAR SKIES TONIGHT INTO SATURDAY MORNING.

AN UPPER LOW CURRENTLY OVER THE SOUTHWEST CONUS IS EXPECTED TO BE
PICKED UP BY AN UPPER LEVEL NORTHERN STREAM TROUGH DROPPING INTO THE
NORTH CENTRAL CONUS ON SATURDAY. AS THE UPPER LOW HEADS NORTHEAST TO
THE OHIO VALLEY...WE WILL SEE MID AND UPPER LEVEL CLOUDS INCREASE.
VIRGA WILL EVENTUALLY WORK TO MOISTEN LOWER LEVELS...AND SOME LIGHT
PRECIP CAN NOT BE RULED OUT LATE SATURDAY OR SATURDAY EVENING.
HOWEVER...ABOUT THE TIME THE LOWER LEVELS MOISTEN...MID/UPPER LEVEL
DRYING IS FORECAST AS THE SYSTEM ALOFT DEPARTS. THIS WILL LEAVE A
NARROW WINDOW OF OPPORTUNITY FOR PRECIP...AND HAVE ONLY USED 20
PERCENT POPS. CONDITIONS LOOK MARGINAL FOR RAIN VERSUS SNOW.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 255 AM EST FRI JAN 4 2013

THE MODELS START OFF IN GOOD AGREEMENT AND REMAIN IN GOOD AGREEMENT
THROUGH TUESDAY. HOWEVER...STILL SIGNIFICANT TIMING ISSUES WITH THE
NEXT WEATHER MAKER TOWARDS THE MIDDLE OF NEXT WEEK...LEADING TO VERY
LOW CONFIDENCE AT THIS TIME.

STARTING OFF THE FORECAST ON SUNDAY...IT LOOKS LIKE A TRANQUIL
PERIOD OF WEATHER IS EXPECTED DURING THE DAY...BUT A FAST MOVING
CLIPPER WILL DROP SOUTHEAST AND PROVIDE A QUICK SHOT FOR SOME
ISOLATED SNOW SHOWERS TOWARDS 00Z MONDAY. MOISTURE REMAINS VERY
WEAK...BUT UPSLOPE FLOW COULD HELP GENERATE THE NEEDED LIFT FOR A
FEW SNOW SHOWERS. NOT ANTICIPATING ANY ACCUMULATIONS AT THIS TIME.
MID LEVEL RIDING WILL SPREAD INTO THE AREA BY DAYBREAK MONDAY...WITH
CLEAR SKIES RETURNING. THIS WILL YIELD ANOTHER COLD START TO THE
DAY...BUT WE SHOULD SEE A NICE RECOVERY UNDER SUNNY SKIES ON MONDAY.
AS THE HIGH PRESSURE RIDGE PUSHES EAST...RETURN FLOW WILL ALLOW FOR
A FAIRLY GOOD WARM UP FOR THE EARLY TO MIDDLE PORTIONS OF NEXT WEEK.
HIGHS TUESDAY...WEDNESDAY...AND THURSDAY COULD PUSH 50 OR EXCEED IT.
HOWEVER...THE BIG QUESTION REMAINS HOW FAST THE NEXT WEATHER SYSTEM
ARRIVES FROM THE DESERT SOUTHWEST. GFS HAS ACTUALLY SPED UP THE
SYSTEM EVEN MORE AND NOW BRINGS A FAIRLY ROBUST SHORTWAVE TROUGH
INTO THE OHIO RIVER VALLEY ON WEDNESDAY. THE 00Z ECMWF REMAINS MUCH
SLOWER WITH THE MAIN SYSTEM NOT ARRIVING UNTIL THURSDAY. THE GFS
ENSEMBLE MEMBERS REMAIN IN CONSIDERABLE DISAGREEMENT...SO PLAN TO
KEEP A BROAD PERIOD OF LOW POPS IN THE FORECAST FROM LATE TUESDAY
NIGHT THROUGH THURSDAY EVENING. WITH THE WARM AIR MASS IN PLACE...AND
NO COLD AIR WRAPPING INTO THIS SYSTEM...PRECIPITATION WILL REMAIN
RAIN.

REGARDLESS OF THE TIMING OF THIS SYSTEM...IT LOOKS LIKE DRIER
WEATHER SHOULD RETURN BY FRIDAY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 606 AM EST FRI JAN 4 2013

A DECK OF CLOUDS IN THE RANGE OF 2500-3500 FEET WILL MOVE OVER THE
NORTHERN AND EASTERN PORTIONS OF THE FORECAST AREA THIS MORNING...AND
THEN THIN OUT TO A SCATTERED LAYER IN THE AFTERNOON. THIS WILL BRING
A PERIOD OF MVFR TO MANY LOCATIONS NORTH OF A LINE FROM SOMERSET TO
PIKEVILLE. WEST WINDS WILL KICK IN DURING THE DAY...ESPECIALLY NEAR
AND NORTH OF INTERSTATE 64...WHERE GUSTS OF 20-25 KNOTS ARE EXPECTED.

WINDS WILL DIE DOWN EARLY THIS EVENING AND SKIES WILL CLEAR...LEAVING
VFR AND LIGHT WINDS THROUGH THE REMAINDER OF THE PERIOD.


&&

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

$$

UPDATE...HAL
SHORT TERM...HAL
LONG TERM....KAS
AVIATION...HAL







AREA FORECAST DISCUSSION

NWS JACKSON KY

 606 AM EST FRI JAN 4 2013

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 240 AM EST FRI JAN 4 2013

STILL NO SIGNIFICANT SYSTEMS TO CONTEND WITH IN THE SHORT TERM...BUT
THERE AREA A COUPLE OF ANNOYING ITEMS.

THE FIRST OF THESE IS THE LOW CLOUD DECK WHICH HAS BEEN SLOWLY
SINKING SOUTH OVER THE OHIO VALLEY DURING THE NIGHT. THE NAM IS NOT
MUCH HELP...ONCE AGAIN DOING VERY POORLY HANDLING LOW LEVEL MOISTURE.
THE GFS AT LEAST KNEW THAT IT WAS THERE...BUT THE CLOUDS HAVE
PROGRESSED SOUTH DURING THE NIGHT A BIT MORE THAN THE GFS SHOWED. THE
RUC IS PERHAPS PERFORMING THE BEST...BUT IS ONLY AVAILABLE THROUGH
18Z FRIDAY. WILL USE THE RUC THROUGH ITS PERIOD OF AVAILABILITY...AND
FOLLOW UP WITH THE GFS TREND OF DRYING UP THE CLOUDS DURING THE LATE
AFTERNOON AND EARLY EVENING.

RIDGING BUILDING IN AT THE SURFACE AND ALOFT SHOULD BRING MAINLY
CLEAR SKIES TONIGHT INTO SATURDAY MORNING.

AN UPPER LOW CURRENTLY OVER THE SOUTHWEST CONUS IS EXPECTED TO BE
PICKED UP BY AN UPPER LEVEL NORTHERN STREAM TROUGH DROPPING INTO THE
NORTH CENTRAL CONUS ON SATURDAY. AS THE UPPER LOW HEADS NORTHEAST TO
THE OHIO VALLEY...WE WILL SEE MID AND UPPER LEVEL CLOUDS INCREASE.
VIRGA WILL EVENTUALLY WORK TO MOISTEN LOWER LEVELS...AND SOME LIGHT
PRECIP CAN NOT BE RULED OUT LATE SATURDAY OR SATURDAY EVENING.
HOWEVER...ABOUT THE TIME THE LOWER LEVELS MOISTEN...MID/UPPER LEVEL
DRYING IS FORECAST AS THE SYSTEM ALOFT DEPARTS. THIS WILL LEAVE A
NARROW WINDOW OF OPPORTUNITY FOR PRECIP...AND HAVE ONLY USED 20
PERCENT POPS. CONDITIONS LOOK MARGINAL FOR RAIN VERSUS SNOW.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 255 AM EST FRI JAN 4 2013

THE MODELS START OFF IN GOOD AGREEMENT AND REMAIN IN GOOD AGREEMENT
THROUGH TUESDAY. HOWEVER...STILL SIGNIFICANT TIMING ISSUES WITH THE
NEXT WEATHER MAKER TOWARDS THE MIDDLE OF NEXT WEEK...LEADING TO VERY
LOW CONFIDENCE AT THIS TIME.

STARTING OFF THE FORECAST ON SUNDAY...IT LOOKS LIKE A TRANQUIL
PERIOD OF WEATHER IS EXPECTED DURING THE DAY...BUT A FAST MOVING
CLIPPER WILL DROP SOUTHEAST AND PROVIDE A QUICK SHOT FOR SOME
ISOLATED SNOW SHOWERS TOWARDS 00Z MONDAY. MOISTURE REMAINS VERY
WEAK...BUT UPSLOPE FLOW COULD HELP GENERATE THE NEEDED LIFT FOR A
FEW SNOW SHOWERS. NOT ANTICIPATING ANY ACCUMULATIONS AT THIS TIME.
MID LEVEL RIDING WILL SPREAD INTO THE AREA BY DAYBREAK MONDAY...WITH
CLEAR SKIES RETURNING. THIS WILL YIELD ANOTHER COLD START TO THE
DAY...BUT WE SHOULD SEE A NICE RECOVERY UNDER SUNNY SKIES ON MONDAY.
AS THE HIGH PRESSURE RIDGE PUSHES EAST...RETURN FLOW WILL ALLOW FOR
A FAIRLY GOOD WARM UP FOR THE EARLY TO MIDDLE PORTIONS OF NEXT WEEK.
HIGHS TUESDAY...WEDNESDAY...AND THURSDAY COULD PUSH 50 OR EXCEED IT.
HOWEVER...THE BIG QUESTION REMAINS HOW FAST THE NEXT WEATHER SYSTEM
ARRIVES FROM THE DESERT SOUTHWEST. GFS HAS ACTUALLY SPED UP THE
SYSTEM EVEN MORE AND NOW BRINGS A FAIRLY ROBUST SHORTWAVE TROUGH
INTO THE OHIO RIVER VALLEY ON WEDNESDAY. THE 00Z ECMWF REMAINS MUCH
SLOWER WITH THE MAIN SYSTEM NOT ARRIVING UNTIL THURSDAY. THE GFS
ENSEMBLE MEMBERS REMAIN IN CONSIDERABLE DISAGREEMENT...SO PLAN TO
KEEP A BROAD PERIOD OF LOW POPS IN THE FORECAST FROM LATE TUESDAY
NIGHT THROUGH THURSDAY EVENING. WITH THE WARM AIR MASS IN PLACE...AND
NO COLD AIR WRAPPING INTO THIS SYSTEM...PRECIPITATION WILL REMAIN
RAIN.

REGARDLESS OF THE TIMING OF THIS SYSTEM...IT LOOKS LIKE DRIER
WEATHER SHOULD RETURN BY FRIDAY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 606 AM EST FRI JAN 4 2013

A DECK OF CLOUDS IN THE RANGE OF 2500-3500 FEET WILL MOVE OVER THE
NORTHERN AND EASTERN PORTIONS OF THE FORECAST AREA THIS MORNING...AND
THEN THIN OUT TO A SCATTERED LAYER IN THE AFTERNOON. THIS WILL BRING
A PERIOD OF MVFR TO MANY LOCATIONS NORTH OF A LINE FROM SOMERSET TO
PIKEVILLE. WEST WINDS WILL KICK IN DURING THE DAY...ESPECIALLY NEAR
AND NORTH OF INTERSTATE 64...WHERE GUSTS OF 20-25 KNOTS ARE EXPECTED.

WINDS WILL DIE DOWN EARLY THIS EVENING AND SKIES WILL CLEAR...LEAVING
VFR AND LIGHT WINDS THROUGH THE REMAINDER OF THE PERIOD.

&&

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

$$

SHORT TERM...HAL
LONG TERM....KAS
AVIATION...HAL







AREA FORECAST DISCUSSION

NWS CHARLESTON WV

 936 AM EST FRI JAN 4 2013

.SYNOPSIS...
SURFACE HIGH PRESSURE BUILDS IN FOR TONIGHT. TWO MID/UPPER LEVEL
TROUGHS PASS THIS WEEKEND. HIGH PRESSURE THEN BUILDS IN...AND
DOMINATES FOR MONDAY AND TUESDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
930AM UPDATE...
STRATOCU SHOWING SIGNS OF SCT OUT ACROSS SE OH AND GREENBRIER
VALLEY AS CLOSED H5 LOW APPROACHES. NOT EXPECTING ANYTHING WITH
THIS OTHER THAN TO HELP TO SCT OUT CLDS. USED RAP AS BASE FOR
TIMING IMPROVING SKY CONDITION TDY...HEDGING SOMEWHAT QUICKER ON
WESTERN FLANKS. THINK AREAS ALONG AND E OF I79 CORRIDOR MAY
STRUGGLE TO SEE ANY PEAKS OF SUN. TWEAKED TEMPS TODAY USING LATEST
LAMP GUIDANCE WHICH RESULTED IN KNOCKING DOWN HIGHS A TICK. STILL
EXPECTING SOME GUSTY WINDS THIS AFTN...PARTICULARLY FOR LOCALES
THAT CAN RID THEMSELVES OF CLDS AND ALSO IN MTNS.

PREVIOUS DISCUSSION BELOW...
STRATUS DECK CURRENTLY IN PLACE ACROSS THE FORECAST AREA...WITH A
FEW REPORTS OF FLURRIES OR LIGHT SNOW. THINK THE CHANCE FOR
MEASURABLE PRECIPITATION IS FAIRLY LIMITED...BUT WILL LINGER SOME
SLIGHT CHANCE POPS ACROSS THE NORTHERN MOUNTAINS EARLY THIS MORNING.
CLOUDS WILL GRADUALLY BREAK UP FROM WEST TO EAST THROUGH THE
DAY AS...LINGERING IN THE NORTHERN MOUNTAINS THE LONGEST. A VERY
MOISTURE STARVED 500 MB LOW WILL CROSS THE AREA THIS AFTERNOON
TODAY. WITH HIGH PRESSURE MOVING IN AT THE SURFACE...DO NOT EXPECT
ANYTHING FROM THE UPPER LEVEL WAVE...IF ANYTHING IT MAY INCREASE
MIXING AND HELP THE DRY AIR ERODE THE LAYER OF CLOUDS LATER TODAY.
00Z GFS DOES TRY TO SHOW SOME PRECIP THROUGH THIS AFTERNOON...BUT
ITS THE ONLY ONE SO WILL KEEP FORECAST DRY. BOUNDARY LAYER WINDS
BECOME A BIT BREEZY TODAY AND TONIGHT...SO LOOKING AT SW WINDS
PICKING UP TODAY...AND LINGERING INTO TONIGHT.

STAYED BELOW MAV/MET GUIDANCE FOR HIGHS TODAY AS 850 THERMAL TROUGH
SLIDES THROUGH. GOING JUST A BIT COOLER THAN THURSDAY...WITH MID TO
UPPER 30S ACROSS THE LOWLANDS...AND 20S TO LOW 30S IN THE HIGHER
TERRAIN. 850S BEGIN WARMING OVERNIGHT...BUT LATE ENOUGH TO REALLY
ONLY HAVE IMPACTS IN THE HIGHER TERRAIN WHERE WE COULD SEE SOME
GRADUAL PRE-DAWN WARMING ABOVE 2500-3000 FEET. ONLY MADE MINOR
TWEAKS TO THE LOWS FOR TONIGHT...WITH GENERALLY TEENS TO LOW 20S
ACROSS THE BOARD.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
2 MID/UPPER LEVEL DISTURBANCES PASS...ONE OVERNIGHT SATURDAY
NIGHT...THE OTHER SUNDAY NIGHT.  A WEAK SURFACE COLD FRONT
ASSOCIATED WITH THE 2ND ONE.  BOTH SYSTEMS DEALING WITH PRECIPITABLE
WATER MAXIMUM OF AROUND .4 TO .5 INCHES.

THE ONLY SIGNIFICANT CHANGE MADE TO OUR FORECAST WAS TO SLOW DOWN
THE INCREASE IN POPS A BIT FOR SUNDAY...WITH THE PEAK OF THE LIMITED
MOISTURE SWEEPING THROUGH SUNDAY EVENING.  LEFT SOUTHERN COUNTIES
WITH POP AOB 14 PCT FOR SUNDAY MORNING...BEFORE INCREASING LATER IN
THE DAY. WAS ALSO A BIT SLOWER ENDING THE SNOW SHOWERS IN THE
CENTRAL WV MOUNTAINS OVERNIGHT SUNDAY NIGHT.

STILL DRY MONDAY INTO TUESDAY.  LOWERED MAXIMUM TEMPERATURE MONDAY A
BIT...FIGURING MAIN WARM UP ARRIVES TUESDAY.

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
BASED ON SURROUNDING OFFICES AND 00Z MODELS...MADE A MINOR CHANGE IN
EXTENDED...TO INTRODUCE POPS A FASTER WEDNESDAY NIGHT.  00Z GFS THE
FASTEST WITH THE PCPN SINCE ITS MID LEVEL CIRCULATION NOT AS STRONG
AS ECMWF. YET...DID NOT JUMP ON THE GFS SPEED AS THIS TIME...BUT
TRENDED A BIT FASTER. SHOULD BE MOSTLY RAIN.

&&

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
MVFR CEILING IN PLACE ACROSS MOST OF CWA...EXCEPT FOR VERY
SOUTHERN TIP. LINGERED THE LOWER CLOUDS LONGER THAN PREVIOUS
FORECAST...ERODING FROM WEST TO EAST LATE MORNING INTO THE
AFTERNOON...AND LINGERING INTO THE EVENING ACROSS THE NORTHERN
MOUNTAINS. COULD EVEN GET SOME VERY ISOLATED LIGHT
SNOW/FLURRIES...MAINLY IN THE NORTHERN MOUNTAINS UNTIL CLOUDS
BREAK UP. VFR SHOULD THEN PREVAIL THROUGH THE REMAINDER OF THE TAF
PERIOD.

SURFACE FLOW TO INCREASE OUT OF THE WEST SOUTHWEST TODAY WITH
GUSTS TO AROUND 20-25KTS IN THE AFTERNOON WITH MIXING.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SATURDAY...

FORECAST CONFIDENCE: MEDIUM.

ALTERNATE SCENARIOS: TIMING OF BREAKUP OF STRATUS DECK MAY VARY.

EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH:   TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW:    TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.

UTC 1HRLY       14   15   16   17   18   19   20   21   22   23   00   01
EST 1HRLY       09   10   11   12   13   14   15   16   17   18   19   20
CRW CONSISTENCY  H    H    H    M    M    M    M    M    M    M    M    H
HTS CONSISTENCY  H    H    H    M    M    M    M    M    M    M    M    H
BKW CONSISTENCY  H    H    M    M    M    M    M    M    M    M    M    H
EKN CONSISTENCY  L    L    H    H    H    M    M    M    M    M    M    H
PKB CONSISTENCY  L    L    H    H    M    M    M    M    M    M    M    H
CKB CONSISTENCY  L    L    L    M    M    M    M    M    M    M    M    H

AFTER 12Z SATURDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.

&&

$$
SYNOPSIS...KTB/ARJ/MZ
NEAR TERM...MZ/30
SHORT TERM...KTB
LONG TERM...ARJ
AVIATION...MZ










AREA FORECAST DISCUSSION

NWS DENVER/BOULDER CO

 932 AM MST FRI JAN 4 2013

.UPDATE...

&&

.SHORT TERM...CURRENT FORECASTS STILL ON TRACK. DRY AND WEAK
NORTHEAST FLOW ALOFT TO PREVAIL ACROSS COLORADO WITH A SLIGHT
WARMUP. HOWEVER...PERSISTANT INVERSIONS WILL KEEP COLD AIR
TRAPPED IN THE MOUNTAIN VALLEYS AND LOW LYING AREAS ACROSS PLAINS.
ELSEWHERE...TEMPERATURES TO WARM TO NEAR SEASONAL NORMALS. CURRENT
TEMP GRIDS LOOK REASONABLE. WINDS TO BE GENERALLY LIGHT AS WEAK
SURFACE GRADIENT PREVAILS.

.AVIATION...CURRENT TAF TRENDS LOOK REASONABLE. LATEST HRRR AND
RAP CONTINUE TO SHOW LIGHT EASTERLY WINDS THROUGH THE AFTERNOON
WITH DRAINAGE FOR THE EVENING. VFR TO CONTINUE WITH UNLIMITED
CEILINGS.

&&

.PREV DISCUSSION... /ISSUED 317 AM MST FRI JAN 4 2013/

SHORT TERM...AN UPPER LEVEL RIDGE AXIS TO THE NORTH OF COLORADO
COUPLED WITH A CLOSED LOW MOVING ACROSS CENTRAL NEW MEXICO WILL
ALLOW FOR A DRY AND RELATIVELY WEAK NORTHEASTERLY FLOW OVER THE
CWFA. WEAK SURFACE LOW PRESSURE WILL STRETCH FM NORTH TO SOUTH
ACROSS THE EASTERN PLAINS WITH GENERALLY WEAK GRADIENT WINDS.
TEMPERATURES WILL BE NEAR SEASONAL NORMALS FOR DENVER.

LONG TERM...UPPER LEVEL RIDGE WILL BE OVER THE GREAT BASIN SATURDAY
AND THEN SHIFT EAST ACROSS COLORADO SUNDAY AS AN UPPER LEVEL TROUGH
MOVES ONTO THE WEST COAST. LARGE DIFFERENCES EXIST BETWEEN THE
MODELS ON HOW THE UPPER LEVEL TROUGH WILL EVOLVE AND WHERE IT WILL
TRACK. THE GFS AND NAM SHOW THIS THROUGH WILL MOVE ACROSS COLORADO
IN PIECES WITH THE FIRST SHORT WAVE MOVING ACROSS SUNDAY NIGHT. THE
MAIN TROUGH WILL LAG BEHIND IT ON MONDAY NIGHT. THE ECMWF AND CMC
INDICATE THIS TROUGH WILL CLOSE OFF AND DIVE SOUTH INTO NORTHERN
MEXICO. THE LOW WILL THEN SLOWLY TRACK EAST ACROSS NORTHERN MEXICO
AND INTO TEXAS WEDNESDAY. EVEN IF THE GFS AND NAM ARE CORRECT...THEY
INDICATE A DRY DOWNSLOPE FLOW ACROSS THE FRONT RANGE. WILL HAVE LOW
POPS FOR THE MOUNTAINS MONDAY AND TUESDAY IN CASE THE GFS AND NAM
SOLUTION PANS OUT. TEMPERATURES WILL BE NEAR TO SLIGHTLY BELOW
NORMAL THIS WEEKEND AND EARLY NEXT WEEK.

FOR WEDNESDAY AND THURSDAY...MODELS COME BACK INTO BETTER AGREEMENT
OVER THE CENTRAL ROCKIES. AN UPPER LEVEL TROUGH WILL BE OVER THE
PACIFIC NORTHWEST WEDNESDAY AND THEN DIVE SOUTHEAST...ENDING UP OVER
THE GREAT BASIN THURSDAY. THIS WILL PRODUCE A WESTERLY FLOW ALOFT
WEDNESDAY AND SOUTHWESTERLY THURSDAY OVER COLORADO. EXPECT DRY
CONDITIONS AND NEAR NORMAL CONDITIONS TO PREVAIL. MOISTURE WILL
INCREASE AS THIS TROUGH NEARS ON THURSDAY...SO WILL HAVE LOW POPS
FOR THURSDAY. BETTER CHANCE FOR SNOW WILL COME FRIDAY AS THE TROUGH
MOVES OVER COLORADO.

AVIATION...VFR CONDITIONS OVER THE NEXT 24+ HOURS. SURFACE WINDS
WILL GENERALLY REMAIN SOUTHWESTERLY...STRONGEST UNTIL AROUND 15Z
THEN WEAKENING THIS AFTN...THEN INCREASING AGAIN THIS EVENING IN
RESPONSE TO THE DIURNAL DRAINAGE.

&&

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

$$

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




AREA FORECAST DISCUSSION

NWS DODGE CITY KS

 255 PM CST FRI JAN 4 2013

...UPDATED SYNOPSIS AND SHORT TERM DISCUSSION...

.SYNOPSIS...
ISSUED AT 254 PM CST FRI JAN 4 2013

THE 12Z UPPER AIR ANALYSIS SHOWED A CLOSED LOW AT 500 MB SPINNING
OVER NEW MEXICO THIS MORNING.  THE ANALYSIS SHOWS THAT THIS SYSTEM
DOES NOT HAVE A LOT OF MOISTURE TO WORK WITH BUT SATELLITE IMAGERY
SHOWED MID AND HIGH LEVEL CLOUDINESS AHEAD OF THIS SYSTEM SPREADING
UP TOWARD SOUTHWEST KANSAS THIS AFTERNOON.  IN THE LOWER LEVELS, A
RIDGE OF HIGH PRESSURE AT 850 MB EXTENDED FROM SOUTHEAST TEXAS BACK
INTO THE FOUR CORNERS REGION.  AT THE SURFACE, A LOW PRESSURE TROUGH
WAS SLOWLY DEEPENING OVER EASTERN COLORADO.  SURFACE DEWPOINTS WERE
GENERALLY IN THE TEENS OVER SOUTHWEST KANSAS WHILE FARTHER SOUTH,
OVER THE TEXAS PANHANDLE INTO WESTERN OKLAHOMA, DEWPOINTS WERE IN
THE LOWER TO MIDDLE 20S.

&&

.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 254 PM CST FRI JAN 4 2013

THE UPPER LOW IS PROGGED BY THE MODELS TO MOVE FROM NEW MEXICO THIS
AFTERNOON THROUGH THE TEXAS PANHANDLE INTO EASTERN KANSAS BY
SATURDAY AFTERNOON.  MODEL SOUNDINGS MOISTEN UP IN THE MID LEVELS
ACROSS SOUTH CENTRAL KANSAS THIS EVENING AND START TO MOISTEN
DOWNWARD WITH TIME.  THE MODELS CONTINUE TO BE SKIMPY ON QPF WITH
THIS SYSTEM WHICH MAKES SENSE GIVEN THE LIMITED MOISTURE.  THINK
THAT THERE COULD AT LEAST BE SOME FLURRIES FOR A PERIOD OF TIME
TONIGHT AND HAVE ADDED THAT TO THE GRIDS IN SOUTH CENTRAL KANSAS.

SURFACE WINDS WERE GRADUALLY VEERING WITH TIME THIS AFTERNOON AS THE
EASTERN COLORADO TROUGH DEEPENS IN ADVANCE OF THE UPPER WAVE.  THIS
WILL ALLOW WEAK LOW LEVEL MOIST ADVECTION TO OCCUR OVER SOUTHWEST
KANSAS THIS EVENING.  WITH THE MOISTURE RIDING UP OVER SNOW COVERED
GROUND, WE SHOULD SEE SOME FOG DEVELOP LATER THIS EVENING AND
CONTINUING THROUGH TONIGHT.  MOS OUTPUT IS NOT INDICATING ANY
REDUCTION IN VISIBILITY AT ALL TONIGHT AND THE HRRR MODEL DOES NOT
INDICATE MUCH EITHER BEFORE 08Z. THE SREF PROBABILITIES DO SHOW SOME
INCREASED CHANCES FOR FOG SO WILL CONTINUE THE TREND OF SOME AREAS
OF FOG DEVELOPING.  WILL ALSO START THE AREAS OF FOG FARTHER WEST
TOWARD GARDEN CITY AND SYRACUSE LATE THIS EVENING.  FOR NOW WILL
HOLD OFF ON ANY HEADLINES AND LET THE NEXT SHIFT MAKE THAT
ASSESSMENT.

ON SATURDAY THE ANY LINGERING FOG IN THE EARLY MORNING SHOULD
DISSIPATE OR MOVE EAST OUT OF CENTRAL KANSAS AS THE SURFACE TROUGH
CONTINUES EAST.  THE REMAINDER OF THE DAY SHOULD SEE MAINLY SUNNY
SKIES.  WITH A LITTLE BETTER MIXING THAN TODAY, HIGH TEMPERATURES
SHOULD BE ABLE TO CLIMB INTO THE 30S OVER THE SNOW COVERED AREAS
WITH LOWER TO MIDDLE 40S IN SOUTH CENTRAL KANSAS WHERE THE SNOW HAS
MELTED.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 227 PM CST FRI JAN 4 2013

A WEAK, UPPER LEVEL HIGH PRESSURE RIDGE OVER THE PLAINS SUNDAY AND
INTO MONDAY WILL START TO BREAK DOWN BY LATE TUESDAY, AS A LARGE
UPPER LEVEL LOW PRESSURE SYSTEM APPROACHES FROM THE SOUTHWEST.
BOTH SUNDAY AND MONDAY WILL BE WARMER THAN IT HAS BEEN RECENTLY,
AND PLENTY OF SUNSHINE SHOULD HELP MELT MORE OF THE SNOW COVER.
HIGHS SUNDAY, MONDAY AND TUESDAY WILL RANGE FROM AROUND THE 40F
DEGREE NORTH OF THE I-70, TO THE MID TO UPPER 40S ALONG AND NEAR
THE OKLAHOMA BORDER.  THEN ON TUESDAY NIGHT, SYNOPTIC SCALE LIFT
WILL RESULT FROM THE CLOSED LOW APPROACHING FROM THE SOUTHWEST.
MOISTURE WILL BE DEEPENING AND ADVECTING NORTH INTO SOUTHWESTERN
KANSAS, AND ESPECIALLY SOUTH CENTRAL KANSAS.  THAT UPPER SYSTEM
WILL CONTINUE TO MARCH INTO THE TEXAS PANHANDLE BY 09/18Z OR WED
AFTERNOON, WHERE IT WILL THEN BEGIN TO LIFT NORTHEAST AND START TO
OPEN UP AS A WAVE, AT THE SAME TIME.  AS FOR PRECIPITATION, THE
GOING 20 TO 30 PERCENT OF PRECIPITATION CHANCES, BASICALLY
SOUTHEAST OF A LIBERAL TO PRATT LINE, THROUGH WED/12Z SEEM
REASONABLE. THEN AS THE UPPER LOW LIFTS NORTHEAST LATE WEDNESDAY
INTO EASTERN KANSAS, 20(WEST) TO 35 (EAST) PRECIPITATION CHANCES
WEDNESDAY AFTERNOON AND NIGHT ACROSS ALL OF SOUTHWESTERN KANSAS
ALSO SEEM APPROPRIATE.  PRECIPITATION TYPE WILL VARY FROM RAIN OR
SNOW IN THE DAY TIMES AND LIGHT SNOW IN THE NIGHT TIMES.  AS THE
UPPER SYSTEM LIFTS OUT WEDNESDAY NIGHT, IT SHOULD ACCELERATE,  AND
CHANCES FOR PRECIPITATION WILL QUICKLY END LATE WEDNESDAY NIGHT OR
VERY EARLY THURSDAY MORNING. AS THIS OCCURS, THERE WILL BE
CLEARING AND COOLING THURSDAY.  A LITTLE WRAP-AROUND COLD AIR WILL
FILTER BACK INTO THE SOUTHWESTERN KANSAS FRIDAY, AND A LITTLE
LIGHT SNOW MAY DEVELOP. LOWER 20 PERCENT CHANCES FOR LIGHT SNOW
EXIST FOR FRIDAY.

WEDNESDAY AND THURSDAY LOOK TO WARM INTO THE LOWER TO MIDDLE 40S
NORTH OF JETMORE, AND AROUND 50F DEGREES SOUTH OF THE JETMORE-DODGE
CITY AREAS.  ON FRIDAY, IT WILL COOL OFF TO HIGHS IN THE 30S.

MINIMUM TEMPERATURES WILL START OUT COLD SATURDAY MORNING, IN THE
TEENS OVER THE SNOW PACKED AREAS NORTHWEST OF A WAKEENEY TO GARDEN
CITY TO ELKHART LINE, AND RANGE TO THE MID 20S IN THE COLDWATER AND
MEDICINE LODGE AREAS.  MEDIUM RANGE MODELS WARM MINIMUMS TO AROUND
THE 20F DEGREE MARK IN THE SCOTT CITY AREA BY TUESDAY, AND TO NEAR
30F DEGREES IN THE PRATT AREA.  THE SLIGHT WARMING TREND WILL EXTEND
INTO THURSDAY MORNING, WITH LOWS FROM THE MID 20S IN SYRACUSE AND
SCOTT CITY, RANGING TO THE LOWER 30S IN PRATT, KIOWA AND COLDWATER.
MINIMUMS FRIDAY WILL TURN COOLER FROM AROUND 20F DEGREES IN THE KEARNY
COUNTY AREA TO THE UPPER 20S IN THE BARBER COUNTY AREA.  SATURDAY
MORNING (DAY 8) SHOULD BE EVEN COLDER.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1139 AM CST FRI JAN 4 2013

AN UPPER LEVEL LOW PRESSURE SYSTEM OVER NEW MEXICO THIS MORNING
WILL MOVE NORTHEAST INTO EASTERN KANSAS BY MIDDAY SATURDAY. AS THE
SYSTEM APPROACHES, SOUTHWESTERLY WINDS WILL BECOME SOUTHERLY BY
THIS EVENING. THIS WILL BRING AN INCREASE IN LOW LEVEL MOISTURE
ACROSS CENTRAL AND SOUTHWEST KANSAS WHICH IS EXPECTED TO RESULT
IN AREAS OF FOG DEVELOPING LATE THIS EVENING. UNCERTAINTY REMAINS
AS TO HOW WIDESPREAD THE FOG WILL BE AND HOW LOW THE VISIBILITY
WILL BE SO FOR NOW WILL INDICATE MVFR VSBYS IN THE TAFS STARTING
AROUND 05Z-06Z AND CONTINUING UNTIL AROUND 12Z-13Z WHEN A SURFACE
TROUGH WILL PASS THROUGH SOUTHWEST KANSAS AND BRING IMPROVING
VISIBILITIES.

&&

.PRELIMINARY POINT TEMPS/POPS...
DDC  16  38  16  43 /   0   0   0   0
GCK  14  36  13  42 /   0   0   0   0
EHA  14  41  16  45 /   0   0   0   0
LBL  16  39  14  45 /   0   0   0   0
HYS  15  35  16  37 /   0   0   0   0
P28  25  42  20  44 /  10   0   0   0

&&

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

$$

SYNOPSIS...GERARD
SHORT TERM...GERARD
LONG TERM...BURKE
AVIATION...GERARD







AREA FORECAST DISCUSSION

NWS JACKSON KY

 135 PM EST FRI JAN 4 2013

.UPDATE...
ISSUED AT 136 PM EST FRI JAN 4 2013

SHORT WAVE IS MOSTLY THROUGH EASTERN KENTUCKY. IT ONLY PRODUCED SOME
TEMPORARY CLOUDS AS IS PASSED ACROSS THE AREA. UPDATED THE FORECAST
TO BETTER REFLECT CURRENT CONDITIONS AND MODEL TRENDS. NO ZONE
UPDATES WILL BE REQUIRED...HOWEVER UPDATES WERE SENT TO NDFD AND THE
POINT AND CLICK.

UPDATE ISSUED AT 1015 AM EST FRI JAN 4 2013

UPDATED THE FORECAST TO BETTER REFLECT MODEL TRENDS AND CURRENT
CONDITIONS. MAIN ADJUSTMENTS WERE FOR THE CLOUDS MOVING ACROSS THE
AREA AS A POTENT...BUT DRY...UPPER TROUGH MOVES ACROSS THE AREA THIS
AFTERNOON.

UPDATE ISSUED AT 742 AM EST FRI JAN 4 2013

HAVE UPDATED THE GRID DATABASE TO BLEND OBSERVED EARLY MORNING CLOUD
AND TEMPERATURE TRENDS INTO THE AFTERNOON FORECAST.

&&

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 240 AM EST FRI JAN 4 2013

STILL NO SIGNIFICANT SYSTEMS TO CONTEND WITH IN THE SHORT TERM...BUT
THERE ARE A COUPLE OF ANNOYING ITEMS.

THE FIRST OF THESE IS THE LOW CLOUD DECK WHICH HAS BEEN SLOWLY
SINKING SOUTH OVER THE OHIO VALLEY DURING THE NIGHT. THE NAM IS NOT
MUCH HELP...ONCE AGAIN DOING VERY POORLY HANDLING LOW LEVEL MOISTURE.
THE GFS AT LEAST KNEW THAT IT WAS THERE...BUT THE CLOUDS HAVE
PROGRESSED SOUTH DURING THE NIGHT A BIT MORE THAN THE GFS SHOWED. THE
RUC IS PERHAPS PERFORMING THE BEST...BUT IS ONLY AVAILABLE THROUGH
18Z FRIDAY. WILL USE THE RUC THROUGH ITS PERIOD OF AVAILABILITY...AND
FOLLOW UP WITH THE GFS TREND OF DRYING UP THE CLOUDS DURING THE LATE
AFTERNOON AND EARLY EVENING.

RIDGING BUILDING IN AT THE SURFACE AND ALOFT SHOULD BRING MAINLY
CLEAR SKIES TONIGHT INTO SATURDAY MORNING.

AN UPPER LOW CURRENTLY OVER THE SOUTHWEST CONUS IS EXPECTED TO BE
PICKED UP BY AN UPPER LEVEL NORTHERN STREAM TROUGH DROPPING INTO THE
NORTH CENTRAL CONUS ON SATURDAY. AS THE UPPER LOW HEADS NORTHEAST TO
THE OHIO VALLEY...WE WILL SEE MID AND UPPER LEVEL CLOUDS INCREASE.
VIRGA WILL EVENTUALLY WORK TO MOISTEN LOWER LEVELS...AND SOME LIGHT
PRECIP CAN NOT BE RULED OUT LATE SATURDAY OR SATURDAY EVENING.
HOWEVER...ABOUT THE TIME THE LOWER LEVELS MOISTEN...MID/UPPER LEVEL
DRYING IS FORECAST AS THE SYSTEM ALOFT DEPARTS. THIS WILL LEAVE A
NARROW WINDOW OF OPPORTUNITY FOR PRECIP...AND HAVE ONLY USED 20
PERCENT POPS. CONDITIONS LOOK MARGINAL FOR RAIN VERSUS SNOW.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 255 AM EST FRI JAN 4 2013

THE MODELS START OFF IN GOOD AGREEMENT AND REMAIN IN GOOD AGREEMENT
THROUGH TUESDAY. HOWEVER...STILL SIGNIFICANT TIMING ISSUES WITH THE
NEXT WEATHER MAKER TOWARDS THE MIDDLE OF NEXT WEEK...LEADING TO VERY
LOW CONFIDENCE AT THIS TIME.

STARTING OFF THE FORECAST ON SUNDAY...IT LOOKS LIKE A TRANQUIL
PERIOD OF WEATHER IS EXPECTED DURING THE DAY...BUT A FAST MOVING
CLIPPER WILL DROP SOUTHEAST AND PROVIDE A QUICK SHOT FOR SOME
ISOLATED SNOW SHOWERS TOWARDS 00Z MONDAY. MOISTURE REMAINS VERY
WEAK...BUT UPSLOPE FLOW COULD HELP GENERATE THE NEEDED LIFT FOR A
FEW SNOW SHOWERS. NOT ANTICIPATING ANY ACCUMULATIONS AT THIS TIME.
MID LEVEL RIDING WILL SPREAD INTO THE AREA BY DAYBREAK MONDAY...WITH
CLEAR SKIES RETURNING. THIS WILL YIELD ANOTHER COLD START TO THE
DAY...BUT WE SHOULD SEE A NICE RECOVERY UNDER SUNNY SKIES ON MONDAY.
AS THE HIGH PRESSURE RIDGE PUSHES EAST...RETURN FLOW WILL ALLOW FOR
A FAIRLY GOOD WARM UP FOR THE EARLY TO MIDDLE PORTIONS OF NEXT WEEK.
HIGHS TUESDAY...WEDNESDAY...AND THURSDAY COULD PUSH 50 OR EXCEED IT.
HOWEVER...THE BIG QUESTION REMAINS HOW FAST THE NEXT WEATHER SYSTEM
ARRIVES FROM THE DESERT SOUTHWEST. GFS HAS ACTUALLY SPED UP THE
SYSTEM EVEN MORE AND NOW BRINGS A FAIRLY ROBUST SHORTWAVE TROUGH
INTO THE OHIO RIVER VALLEY ON WEDNESDAY. THE 00Z ECMWF REMAINS MUCH
SLOWER WITH THE MAIN SYSTEM NOT ARRIVING UNTIL THURSDAY. THE GFS
ENSEMBLE MEMBERS REMAIN IN CONSIDERABLE DISAGREEMENT...SO PLAN TO
KEEP A BROAD PERIOD OF LOW POPS IN THE FORECAST FROM LATE TUESDAY
NIGHT THROUGH THURSDAY EVENING. WITH THE WARM AIR MASS IN PLACE...AND
NO COLD AIR WRAPPING INTO THIS SYSTEM...PRECIPITATION WILL REMAIN
RAIN.

REGARDLESS OF THE TIMING OF THIS SYSTEM...IT LOOKS LIKE DRIER
WEATHER SHOULD RETURN BY FRIDAY.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 136 PM EST FRI JAN 4 2013

EXPECTING VFR THE ENTIRE PERIOD. WINDS WILL BE A LITTLE GUSTY THIS
AFTERNOON BUT THEN DIE DOWN. NEXT CHANCE FOR MVFR WILL BE SATURDAY
NIGHT.


&&

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

$$

UPDATE...JJ
SHORT TERM...HAL
LONG TERM....KAS
AVIATION...JJ







AREA FORECAST DISCUSSION

NWS BUFFALO NY

 347 PM EST FRI JAN 4 2013

.SYNOPSIS...
WINDS WILL DIMINISH TONIGHT AS LOW PRESSURE LIFTS INTO QUEBEC AND
THEN FINALLY AWAY FROM THE REGION. HIGH PRESSURE WILL BRING A DRY
SATURDAY...BEFORE AN AREA OF LOW PRESSURE MOVES THROUGH THE GREAT
LAKES SATURDAY NIGHT AND SUNDAY WITH A WIDESPREAD LIGHT SNOWFALL.

&&

.NEAR TERM /THROUGH SATURDAY/...
WINDS LOOK TO HAVE PEAKED ACROSS THE AREA EARLIER THIS AFTERNOON
WITH ONLY A FEW LOCATIONS DOWNWIND OF THE LAKES CONTINUING TO SEE
ADVISORY LEVEL WIND GUSTS. EXPECT WINDS TO BE ENOUGH BELOW THRESHOLD
LEVELS TO DROP THE ADVISORY FOR MUCH OF THE AREA...ONLY HOLDING ONTO
TO IT FOR AREAS NORTHEAST OF THE LAKES. THE STRONG WINDS WILL
CONTINUE TO CAUSE BLOWING AND DRIFTING PROBLEMS INTO THIS EVENING.
THE LOW LEVEL WIND MAXIMUM WILL SHIFT EAST THIS EVENING...COMBINED
WITH A RELAXING OF THE PRESSURE GRADIENT WILL BRING WINDS BELOW
ADVISORY LEVEL DOWNWIND OF THE LAKES BEFORE MIDNIGHT.

AN UPTICK TO SNOW SHOWER ACTIVITY IS EXPECTED TONIGHT EAST OF LAKE
ONTARIO AS A NORTHERN STREAM SHORTWAVE AND ITS ATTENDANT WEAK COLD
FRONT PUSH SOUTHWARD ACROSS THE REGION. THE MEAN WEST TO
SOUTHWESTERLY FLOW AHEAD OF THIS FEATURE WILL BRING SOME OPPORTUNITY
FOR LAKE ENHANCEMENT. HOWEVER...DRIER AIR ADVECTING INTO THE REGION
SHOULD LIMIT ACCUMULATION POTENTIAL AND WE SHOULD ONLY SEE MINOR
ACCUMULATIONS AT BEST. LOCAL WRF RUNS AND HRRR SUGGESTING THE
POSSIBILITY THAT A SNOW NARROW BAND COULD FORM FARTHER TO THE
WEST...BUT THIS POTENTIAL LOOKS LIMITED BASED ON THE AMOUNT OF DRY
AIR ADVECTING INTO THE AREA...WITH AT LEAST PARTIAL CLEARING TAKING
PLACE ACROSS A GOOD PORTION OF THE AREA.

QUIETER WEATHER LOOKS IN STORE FOR SATURDAY AS THE SURFACE HIGH
RIDGES ACROSS THE AREA. ANY MORNING SUNSHINE WILL GIVE WAY TO
INCREASING CLOUD COVER DURING THE AFTERNOON AHEAD OF THE VIGOROUS
SHORTWAVE APPROACHING FROM THE PLAINS.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
SATURDAY NIGHT THROUGH SUNDAY NIGHT...A SERIES OF SHORT WAVES WILL
BE ROUNDING THE BASE OF THE PERSISTENT UPPER LEVEL TROUGH THAT HAS
BEEN IN PLACE OVER SOUTHEAST CANADA AND THE GREAT LAKES. THE LIFT
ASSOCIATED WITH THESE IMPULSES WILL KEEP UNSETTLED WEATHER OVER OUR
AREA UNTIL THE UPPER LEVEL TROUGH LIFTS OUT ACROSS NEW ENGLAND LATER
SUNDAY NIGHT AND MONDAY.

THE FIRST SIGNIFICANT SHORT WAVE IS HEADING SOUTHEAST TOWARD THE
NORTHERN ROCKIES THIS FRIDAY AFTERNOON. THE SURFACE LOW THAT IS
ASSOCIATED WITH THIS SHORT WAVE WILL REACH THE CENTRAL GREAT LAKES
SATURDAY NIGHT BEFORE TRACKING EAST ACROSS LAKE ONTARIO AND NORTHERN
NEW YORK STATE ON SUNDAY. WARM AIR ADVECTION AHEAD OF THE
LOW...COMBINED WITH THE LIFT ASSOCIATED WITH A LEAD SHORT WAVE...
WILL CAUSE LIGHT SNOW TO SPREAD EAST ACROSS THE AREA SATURDAY NIGHT.
EXPECT GENERAL ACCUMULATIONS OF AN INCH OR LESS...WITH SLIGHTLY
HIGHER AMOUNTS POSSIBLE ACROSS THE NORTH COUNTRY AND ST LAWRENCE
RIVER VALLEY WHERE THERE WILL BE ADDITIONAL LIFT IN THE VICINITY OF
A PASSING WARM FRONT.

THERE MAY BE A LULL IN THE GENERAL SNOWFALL SUNDAY MORNING BEFORE
MOISTURE INCREASES AGAIN DURING THE AFTERNOON AS THE SURFACE LOW
PUSHES EAST ACROSS LAKE ONTARIO. ADDITIONAL ACCUMULATIONS OF AN INCH
OR LESS ARE EXPECTED...WITH ANOTHER 1 TO 3 INCHES POSSIBLE EAST OF
LAKE ONTARIO DUE TO CONVERGENCE ALONG THE FRONT THAT WILL BE
EXTENDING EAST OF THE SURFACE LOW.

THE SNOW WILL TAPER OFF FROM WEST TO EAST SUNDAY NIGHT AS THE UPPER
LEVEL TROUGH AND ASSOCIATED SURFACE LOW SLIDE OFF THE NEW ENGLAND
COAST. THE NAM SHOWS MUCH DRIER AIR BUILDING IN BEHIND THE LOW
DURING THE SECOND HALF OF SUNDAY NIGHT...WHILE THE GFS HOLDS THE LOW
LEVEL MOISTURE IN A LITTLE LONGER. IF ENOUGH LOW LEVEL MOISTURE
REMAINS IN PLACE WITH THE NORTHERLY UPSLOPE FLOW BEHIND THE
DEPARTING LOW...SOME LIGHT SNOW OR FREEZING DRIZZLE COULD LINGER
THROUGH THE NIGHT.

HIGH PRESSURE AND DRIER AIR WILL BUILD ACROSS NEW YORK STATE ON
MONDAY AND BRING MOSTLY SUNNY SKIES TO THE AREA. EXPECT MAINLY CLEAR
SKIES MONDAY NIGHT AS THE SURFACE HIGH SLIDES OFF THE NEW ENGLAND
COAST.

A PERSISTENT SOUTHWEST FLOW AHEAD OF THE SURFACE LOW WILL ALLOW
TEMPERATURES TO HOLD STEADY IN THE 20S SATURDAY NIGHT...WITH UPPER
TEENS POSSIBLE EAST OF LAKE ONTARIO. MOST AREAS WILL SEE
TEMPERATURES MODERATING IN THE MID OR UPPER 30S SUNDAY...BEFORE THE
NORTHERLY FLOW BEHIND THE SURFACE LOW CAUSES TEMPERATURES TO FALL
BACK INTO THE UPPER TEENS/LOWER 20S SUNDAY NIGHT. READINGS MAY DIP
INTO THE SINGLE DIGITS EAST OF LAKE ONTARIO. TEMPERATURES WILL
STRUGGLE TO GET OUT OF THE 20S ON MONDAY IN SPITE OF THE ANTICIPATED
SUNSHINE.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
A GENERAL ZONAL FLOW IS FORECAST TO BE IN PLACE ALONG THE
CANADIAN/US BORDER TUESDAY AND WEDNESDAY...WHILE A CLOSED LOW LIFTS
OUT OF THE SOUTHWEST PART OF THE COUNTRY. THE GFS AND ECMWF STILL
HAVE SIGNIFICANT DISCREPANCIES IN THE WAY THEY HANDLE THIS CUTOFF
LOW. THE ECWMF KEEPS THE LOW OVER THE SOUTHERN PLAINS THROUGH
WEDNESDAY...BEFORE LIFTING IT OUT INTO THE MIDWEST ON
THURSDAY...WHILE THE GFS LIFTS THE LOW OUT ON WEDNESDAY AND TRACKS
AN OPEN WAVE TOWARD THE LOWER LAKE ON THURSDAY. FOR NOW...WILL
CONTINUE TO HPC GUIDANCE WHICH SEEMS TO FAVOR THE MORE CONSERVATIVE
ECMWF SOLUTION. BASED ON THIS GUIDANCE...WILL KEEP THE AREA DRY
THROUGH WEDNESDAY NIGHT AS THE SURFACE LOW THAT WILL BE ASSOCIATED
WITH THE CLOSED STAYS WELL TO OUR WEST.

THE ECMWF LIFTS THE CLOSED LOW INTO THE MIDWEST ON THURSDAY...THEN
OPEN THE WAVE UP ON FRIDAY AS IT TRACKS IT EAST ACROSS THE LOWER
LAKES. THE CORRESPONDING SURFACE LOW IS FORECAST TO HEAD NORTHEAST
TOWARD THE CENTRAL GREAT LAKES ON THURSDAY...BEFORE TRACKING NORTH
OF LAKE ONTARIO ON FRIDAY. THE DEEP LAYERED SOUTHERLY FLOW AHEAD OF
THIS SYSTEM WILL TRANSPORT MILDER AIR NORTH TOWARD OUR AREA. WHILE
TEMPERATURES ALOFT LOOK WARM ENOUGH TO SUPPORT MAINLY RAIN...SURFACE
TEMPERATURES WILL BE THE KEY TO THE PCPN TYPE. BASED ON FORECAST
TEMPERATURES...WE MAY SEE A MIX OF FROZEN PCPN THURSDAY MORNING
BEFORE TEMPERATURES WARM UP ENOUGH FOR A POSSIBLE CHANGEOVER TO ALL
RAIN DURING THE AFTERNOON. MIXED PCPN COULD SET UP AGAIN ACROSS THE
HIGHER ELEVATIONS THURSDAY NIGHT BEFORE ALL PCPN CHANGES BACK OVER
TO RAIN ON FRIDAY. STAY TUNED TO LATER MODEL RUNS WHICH WILL HELP TO
FINE TUNE THIS POTENTIAL FOR MIXED PCPN.

REGARDING TEMPERATURES...EXPECT A MODERATING TREND THAT WILL SEE
DAYTIME HIGHS RISING INTO THE UPPER 30S/LOWER 40S ON WEDNESDAY AND
THURSDAY...AND MAYBE EVEN THE MID 40S ON FRIDAY.

&&

.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
BIGGEST AVIATION IMPACT INTO THIS EVENING WILL BE THE STRONG
SOUTHWEST WINDS. KIAG/KBUF/KROC/KART WILL ALL EXPERIENCE WINDS
GUSTS TO AT LEAST 40 KNOTS WITH PERIODIC GUSTS CLOSE TO 50
KNOTS...ESPECIALLY AT KIAG AND KBUF. ALTHOUGH SNOW IS NOT
FALLING...THE STRONG WINDS ARE CREATING BLOWING SNOW WITH VSBY
RESTRICTIONS. THE VSBY RESTRICTIONS WILL BE HIGHLY VARIABLE...BUT
COULD BRIEFLY DROP TO IFR WITH THE HIGHEST WIND GUSTS.

WINDS WILL GRADUALLY DIMINISH THIS EVENING AND OVERNIGHT. DRIER AIR
WILL WORK INTO THE REGION FROM THE WEST TONIGHT WITH SKIES BECOMING
AT LEAST PARTLY CLOUDY. THERE IS A CHANCE FOR A BAND OF LAKE
EFFECT SNOW TO DEVELOP EAST AND SOUTHEAST OF LAKE ONTARIO
TONIGHT...BUT WITH THE DRIER AIR ADVECTING INTO THE REGION
IMPACTS WILL BE MINIMAL.

OUTLOOK...
SATURDAY...MAINLY VFR.
SUNDAY...MVFR/IFR WITH CHANCE OF SNOW SHOWERS.
MONDAY AND TUESDAY...VFR.
WEDNESDAY...VFR/MVFR WITH A CHANCE OF RAIN.

&&

.MARINE...
WINDS GUSTS HAVE LIKELY PEAKED OVER THE LOWER LAKES...BUT GALES WILL
CONTINUE INTO THIS EVENING. ONCE WINDS HAVE LOWERED BELOW GALE FORCE
SMALL CRAFT CONDITIONS WILL LINGER INTO SATURDAY...BEFORE BRIEFLY
DYING OFF FROM MID DAY SATURDAY INTO SATURDAY NIGHT. WINDS WILL
AGAIN RAMP UP FROM THE SOUTHWEST LATE SATURDAY NIGHT AND SUNDAY
AHEAD OF A DEVELOPING LOW WITH SOME SMALL CRAFT CONDITIONS POSSIBLE
DURING THIS TIME FRAME.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR NYZ001>003-007-
     010-011.
MARINE...GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LEZ020-040-041.
         GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LOZ030-
         043>045-063>065.

&&

$$

SYNOPSIS...TMA
NEAR TERM...TMA
SHORT TERM...TJP
LONG TERM...TJP
AVIATION...TMA
MARINE...TMA








AREA FORECAST DISCUSSION

NWS CHARLESTON WV

 307 PM EST FRI JAN 4 2013

.SYNOPSIS...
SURFACE HIGH PRESSURE TONIGHT. TWO MID/UPPER LEVEL TROUGHS PASS THIS
WEEKEND. HIGH PRESSURE THEN BUILDS IN...MONDAY AND EARLY WEDNESDAY.
LOW PRESSURE BRINGS RAIN SHOWERS LATE WEDNESDAY NIGHT AND THURSDAY.

&&

.NEAR TERM /THROUGH SATURDAY/...
USED RAP AND VIS SAT TRENDS AS BASE FOR TIMING IMPROVING SKY
CONDITION INTO TONIGHT. THINK AREAS ALONG AND E OF I79 CORRIDOR
WILL KEEP CLDS WITH N MTNS HOLDING ON UNTIL PERHAPS 15Z. LOWS
TONIGHT TRICKY ONCE AGAIN AND WILL DEPEND ON EXTENT OF CLEARING
AND BL PUFF. LAMP GUIDANCE CONT TO BE ON WARM SIDE...LKLY OWING TO
BL PUFF AND ALSO CLDS ACROSS THE MTNS. DEEPER VALLEYS/HOLLOWS MAY
DECOUPLE THOUGH...GIVING UPPER TEENS. WILL LEAN TOWARD LAMP WHICH
HAS PERFORMED BETTER OVER RECENT COLD BIAS IN MET/MAV AND
INCORPORATE A COLDER SOLUTION FOR TYPICAL COLD SPOTS OUTSIDE OF
THE CLDS.

ANY REMAINING STRATUS ACROSS N MTNS WILL SCT OUT BY LATE
MORNING. SOME HIGH CLDS WILL BE ROLLING IN AFTN FROM SW...HELPING
TO PUT A FILTER ON SUNSHINE. KEPT POPS OUT THROUGH 00Z...WITH DRY
LLVLS IN PLACE. HOWEVER...MAY SEE ENOUGH TOP DOWN MOISTENING FOR
SOME LIGHT PCPN ACROSS SW VA BY 00Z.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
UPPER SPLIT FLOW PATTERN CONTINUES. MODELS IN GOOD AGREEMENT ON
SOUTHERN STREAM UPPER LOW OVER THE SOUTHWEST U.S. WEAKENING AS IT
OPENS UP...AND LIFTS NORTHEASTWARD ACROSS THE OHIO VALLEY SATURDAY
NIGHT IN CONFLUENT FLOW ALOFT. THIS SYSTEM IS FORECAST TO BE TOO
WEAK TO LIFT THE BAROCLINIC ZONE...STILL ACROSS THE SOUTHEASTERN
STATES...NORTHWARD ENOUGH TO AFFECT ALL BUT THE SOUTHEAST PORTION
OUR AREA. WITH THE VORT CENTER OF THE SYSTEM TRACKING ACROSS THE
MIDDLE OHIO VALLEY INTO THE GREAT LAKES...THE EFFECTS OF ITS
DYNAMICS WILL MAINLY CLIP OUR SOUTHEAST OHIO ZONES. THUS...AS A
WHOLE...OUR AREA LOOKS TO BE IN A MIN FOR QPF. WILL KEEP LOW POPS
ACROSS THE AREA SATURDAY NIGHT...WITH THE BEST CHANCE OVER THE
NORTHWEST AND SOUTHEAST AREAS. DRY SLOW MOVES IN BY SUNDAY MORNING
AS THE SOUTHERN STREAM SYSTEM DEPARTS WITH A BREAK IN THE PRECIP.
DURING SUNDAY...A NORTHERN STEAM UPPER TROUGH AND COLD FRONT DROPS
RAPIDLY SOUTHEAST ACROSS THE AREA SUNDAY AFTERNOON...BRINGING
SCATTERED RAIN SHOWERS...CHANGING TO SNOW SHOWERS BEFORE ENDING
SUNDAY NIGHT. AGAIN...EXPECT LIGHT QPF WITH ANY SNOW ACCUMULATIONS
LIMITED TO MAINLY THE NORTHERN MOUNTAINS...GENERALLY AN INCH OR TWO
BY MONDAY MORNING.

BEHIND THIS QUICK HITTER WILL BE HIGH PRESSURE FOR MONDAY WITH
INCREASING SUNSHINE. MAX TEMPERATURES SUNDAY AND MONDAY AFTERNOON
WILL BE SIMILAR IN THE LOW TO MID 40S...SUNDAY MAINLY
DUE TO THE CLOUDS AND MONDAY MAINLY DUE TO THE SUNSHINE.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
HIGH PRESSURE REMAINS IN CONTROL MONDAY NIGHT AND TUESDAY TO PROVIDE
DRY CONDITIONS.

A DEVELOPING LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST
WEDNESDAY NIGHT. DIFFERENCES BETWEEN THE ECMWF AND GFS EXIST. THE
ECMWF IS THE PREFERRED MODELS WITH A LOW LATITUDE CYCLONE BECOMING
LESS PROGRESSIVE...WITH SFC LOW TRACK MOVING FROM THE CENTRAL PLAINS
NORTHEAST INTO THE GREAT LAKES REGION...CONTRARY TO THE GFS THAT
DEVELOPS THE LOW OVER THE SOUTHERN PLAINS...TRACKING THE LOW
OVERHEAD WV.

THEREFORE...MINOR TWEAKS WHERE NEEDED FROM PREVIOUS FORECAST...WITH
CHANCES OF RAIN SHOWERS SPREADING FROM WEST TO EAST LATE WEDNESDAY
NIGHT...WITH THE BULK OF PCPN OCCURRING ON THURSDAY.

TEMPERATURE PROFILES AND BOUNDARY LAYER SOUTHWEST FLOW SUGGEST ALL
PCPN STARTING AS LIQUID BY 15Z THURSDAY. THEREFORE...HIGHEST POPS
WHERE CODED ON THURSDAY. ECMWF H850 STRENGTHENING SOUTH TO SOUTHWEST
FLOW AROUND 50 KNOTS...AND TEMPERATURES NEAR 11C BY 18Z
THURSDAY...SUPPORT A GRADUAL WARMING TREND THRU THURSDAY AFTERNOON.
DECREASED POPS BY 06Z FRIDAY...WITH CHANCE POPS MAINLY OVER NORTHERN
AND EASTERN MOUNTAINS. DRIER AIR MASS EXPECTED BY MID FRIDAY MORNING
WITH PCPN EXITING NORTHEAST.

WENT GENERALLY WITH HPC GUIDANCE FOR TEMPERATURES ADDING FEW LOCAL
DETAILS.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
FOR NE KY/SE OH/SW VA...MVFR STRATOCU WILL CONT TO LIFT INTO LOW END
VFR AND BECOME SCT AFTER SUNSET. ELSEWHERE...WILL CARRY MVFR CIGS
UNTIL LATE AFTN/EARLY EVE...KEEPING KEKN IN MOST OF THE NIGHT. WILL
ALSO ALLOW FOR A RETURN TO BKN MVFR FOR KCKB AFTER 09Z WITH AREA OF
LLVL MOISTURE SWINGING DOWN FROM N. SFC WINDS WILL SLACKEN THIS
EVE...BUT STILL CARRY WESTERLY A LIGHT WIND OVERNIGHT.

VFR CONDITIONS AREAWIDE AFTER 15Z WITH SOME HI CLDS ROLLING IN
FROM SW AFTER 18Z.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SATURDAY...

FORECAST CONFIDENCE: MEDIUM.

ALTERNATE SCENARIOS: TIMING OF BREAKUP OF STRATUS DECK MAY VARY
THIS EVENING.

EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH:   TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW:    TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.

UTC 1HRLY       20   21   22   23   00   01   02   03   04   05   06   07
EST 1HRLY       15   16   17   18   19   20   21   22   23   00   01   02
CRW CONSISTENCY  M    M    M    M    M    M    M    M    M    M    M    M
HTS CONSISTENCY  M    M    M    M    M    M    M    M    M    M    M    M
BKW CONSISTENCY  H    H    H    M    M    M    M    M    M    M    M    M
EKN CONSISTENCY  M    M    M    M    M    M    M    M    M    M    M    M
PKB CONSISTENCY  M    M    M    M    M    M    M    M    M    M    M    M
CKB CONSISTENCY  M    M    M    M    M    M    M    M    M    M    M    M

AFTER 18Z SATURDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.

&&

$$
SYNOPSIS...ARJ/JMV/30
NEAR TERM...30
SHORT TERM...JMV
LONG TERM...ARJ
AVIATION...30











AREA FORECAST DISCUSSION

NWS CHARLESTON WV

 127 PM EST FRI JAN 4 2013

.SYNOPSIS...
SURFACE HIGH PRESSURE BUILDS IN TONIGHT. TWO MID/UPPER LEVEL
TROUGHS PASS THIS WEEKEND. HIGH PRESSURE THEN BUILDS IN...AND
DOMINATES FOR MONDAY AND TUESDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
USED RAP AND VIS SAT TRENDS AS BASE FOR TIMING IMPROVING SKY
CONDITION INTO TONIGHT. THINK AREAS ALONG AND E OF I79 CORRIDOR
WILL KEEP CLDS WITH N MTNS HOLDING ON UNTIL PERHAPS 15Z. LOWS
TONIGHT TRICKY ONCE AGAIN AND WILL DEPEND ON EXTENT OF CLEARING
AND BL PUFF. LAMP GUIDANCE CONT TO BE ON WARM SIDE...LKLY OWING TO
BL PUFF AND ALSO CLDS ACROSS THE MTNS. DEEPER VALLEYS/HOLLOWS MAY
DECOUPLE THOUGH...GIVING UPPER TEENS. WILL LEAN TOWARD LAMP WHICH
HAS PERFORMED BETTER OVER RECENT COLD BIAS IN MET/MAV AND
INCORPORATE A COLDER SOLUTION FOR TYPICAL COLD SPOTS OUTSIDE OF
THE CLDS.

ANY REMAINING STRATUS ACROSS N MTNS WILL SCT OUT BY LATE
MORNING. SOME HIGH CLDS WILL BE ROLLING IN AFTN FROM SW...HELPING
TO PUT A FILTER ON SUNSHINE. KEPT POPS OUT THROUGH 00Z...WITH DRY
LLVLS IN PLACE. HOWEVER...MAY SEE ENOUGH TOP DOWN MOISTENING FOR SOME LIGHT
PCPN ACROSS SW VA BY 00Z.


&&

.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
2 MID/UPPER LEVEL DISTURBANCES PASS...ONE OVERNIGHT SATURDAY
NIGHT...THE OTHER SUNDAY NIGHT.  A WEAK SURFACE COLD FRONT
ASSOCIATED WITH THE 2ND ONE.  BOTH SYSTEMS DEALING WITH PRECIPITABLE
WATER MAXIMUM OF AROUND .4 TO .5 INCHES.

THE ONLY SIGNIFICANT CHANGE MADE TO OUR FORECAST WAS TO SLOW DOWN
THE INCREASE IN POPS A BIT FOR SUNDAY...WITH THE PEAK OF THE LIMITED
MOISTURE SWEEPING THROUGH SUNDAY EVENING.  LEFT SOUTHERN COUNTIES
WITH POP AOB 14 PCT FOR SUNDAY MORNING...BEFORE INCREASING LATER IN
THE DAY. WAS ALSO A BIT SLOWER ENDING THE SNOW SHOWERS IN THE
CENTRAL WV MOUNTAINS OVERNIGHT SUNDAY NIGHT.

STILL DRY MONDAY INTO TUESDAY.  LOWERED MAXIMUM TEMPERATURE MONDAY A
BIT...FIGURING MAIN WARM UP ARRIVES TUESDAY.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
BASED ON SURROUNDING OFFICES AND 00Z MODELS...MADE A MINOR CHANGE IN
EXTENDED...TO INTRODUCE POPS A FASTER WEDNESDAY NIGHT.  00Z GFS THE
FASTEST WITH THE PCPN SINCE ITS MID LEVEL CIRCULATION NOT AS STRONG
AS ECMWF. YET...DID NOT JUMP ON THE GFS SPEED AS THIS TIME...BUT
TRENDED A BIT FASTER. SHOULD BE MOSTLY RAIN.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
FOR NE KY/SE OH/SW VA...MVFR STRATOCU WILL CONT TO LIFT INTO LOW END
VFR AND BECOME SCT AFTER SUNSET. ELSEWHERE...WILL CARRY MVFR CIGS UNTIL
LATE AFTN/EARLY EVE...KEEPING KEKN IN MOST OF THE NIGHT. WILL ALSO
ALLOW FOR A RETURN TO BKN MVFR FOR KCKB AFTER 09Z WITH AREA OF
LLVL MOISTURE SWINGING DOWN FROM N. SFC WINDS WILL SLACKEN THIS
EVE...BUT STILL CARRY WESTERLY A LIGHT WIND OVERNIGHT.

VFR CONDITIONS AREAWIDE AFTER 15Z WITH SOME HI CLDS ROLLING IN
FROM SW AFTER 18Z.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SATURDAY...

FORECAST CONFIDENCE: MEDIUM.

ALTERNATE SCENARIOS: TIMING OF BREAKUP OF STRATUS DECK MAY VARY
THIS EVENING.

EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH:   TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW:    TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.

UTC 1HRLY       18   19   20   21   22   23   00   01   02   03   04   05
EST 1HRLY       13   14   15   16   17   18   19   20   21   22   23   00
CRW CONSISTENCY  H    M    M    M    M    M    M    H    H    H    H    H
HTS CONSISTENCY  H    M    M    M    M    M    M    H    H    H    H    H
BKW CONSISTENCY  H    M    M    M    M    M    M    H    H    H    H    H
EKN CONSISTENCY  H    M    M    M    M    M    M    H    H    H    H    H
PKB CONSISTENCY  M    M    M    M    M    M    M    H    H    H    H    H
CKB CONSISTENCY  H    H    M    M    M    M    M    H    H    H    H    H

AFTER 18Z SATURDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.

&&

$$
SYNOPSIS...ARJ/JMV/30
NEAR TERM...30
SHORT TERM...KTB
LONG TERM...ARJ
AVIATION...30









AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 233 PM CST FRI JAN 4 2013

.SHORT TERM...TONIGHT THROUGH MONDAY
233 PM CST FRI JAN 4 2013

MAIN FORECAST CONCERNS ARE ON LIGHT PRECIPITATION CHANCES SATURDAY
AFTERNOON INTO SATURDAY NIGHT.

CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING ALONG THE WEST COAST OF THE U.S. INTO BRITISH
COLUMBIA...AN UPPER LOW OVER NEW MEXICO...A SHORTWAVE TROUGH OVER
SOUTHERN ALBERTA...WEAK RIDGING OVER THE DAKOTAS AND DEEP TROUGHING
OVER EASTERN CANADA. THE FORECAST AREA WAS UNDER SUBSIDENCE ALOFT
BEING IN NORTHWEST FLOW AHEAD OF THE DAKOTAS RIDGING...RESULTING IN
CLEAR SKIES. IN FACT...MAINLY CLEAR SKIES ENCOMPASS MUCH OF THE
UPPER MIDWEST DUE TO PLENTY OF DRY AIR...SEEN ON 12Z SOUNDINGS FROM
BIS...OAX...MPX AND GRB. ONE THING OF INTEREST ON ALL OF THOSE
SOUNDINGS IS A STRONG AND NEARLY SATURATED INVERSION BETWEEN
925-950MB. AGAIN...DESPITE THE NEAR SATURATION...SKIES ARE STILL
CLEAR. SUNSHINE PLUS THE 925MB TEMPS STARTING OFF IN THE -3 TO -6C
RANGE AT 12Z FROM SOUNDING DATA AND DRY AIR HAS ALLOWED TEMPERATURES
TO CLIMB INTO THE MID 20S TO LOW 30S. TO THE NORTHWEST...HIGH
CLOUDS WERE SPREADING ACROSS SASKATCHEWAN AND NORTH DAKOTA AHEAD
OF THE SOUTHERN ALBERTA SHORTWAVE TROUGH. IN ADDITION...AN AREA OF
LOW PRESSURE HAS FORMED OVER SOUTHERN SASKATCHEWAN WITH A WARM
FRONT EXTENDING SOUTHEAST TO BISMARCK NORTH DAKOTA.

TONIGHT AND SATURDAY...MODELS ARE IN GOOD AGREEMENT DROPPING THE
SHORTWAVE TROUGH OVER ALBERTA THROUGH THE NORTHERN PLAINS AND INTO
NEBRASKA BY 00Z SUNDAY. THIS TROUGH HELPS TO EJECT AND SHEAR OUT THE
NEW MEXICO UPPER LOW...WHICH GETS LIFTED INTO SOUTHERN ILLINOIS AND
INDIANA. THE TRACKS OF THESE FEATURES SPLIT THE FORECAST AREA...
HOWEVER...THERE ARE STILL CONCERNS. THE MAIN ONE IS WITH LOW LEVEL
SATURATION. 925-900MB RH PROGS FROM THE 04.12Z NAM/GFS SHOW THAT AS
THE NEW MEXICO UPPER LOW LIFTS NORTHEAST...AN AREA OF LOW STRATUS
FORMS ACROSS MISSOURI SATURDAY MORNING...WHICH THEN SPREADS INTO
EASTERN IOWA AND SOUTHERN WISCONSIN DURING THE AFTERNOON. ABOVE
900MB...TROPOSPHERE IS STILL PRETTY DRY. ANALYSIS LOOKING AT THE
275-280K SURFACES SHOWS THAT MOISTURE GETS PULLED UP OUT OF THE GULF
OF MEXICO AS THE NEW MEXICO UPPER LOW LIFTS NORTHEAST. IN
ADDITION...THERE IS WEAK LIFT ON THESE SURFACES...WHICH GIVEN THAT
THE TEMPERATURE PROFILE HAS NO ICE...COULD LEAD TO FREEZING DRIZZLE
FORMATION. AS SUCH...HAVE RETAINED A MENTION OF FREEZING DRIZZLE
FROM 21-00Z...BUT RESTRICTED IT TO THE SOUTHEAST 1/3 OF THE AREA TO
CORRELATE WITH THE LIFT ON THE 275-280K SURFACES. ELSEWHERE...DRY
CONDITIONS WILL PREVAIL WITH PERHAPS LITTLE IN THE WAY OF CLOUD
COVER UNTIL LATER SATURDAY. WITH CLEAR SKIES AND DRY AIR TONIGHT...
ALONG WITH LIGHT WINDS IN MOST LOCATIONS EXCEPT FOR SOUTHEAST
MINNESOTA...TEMPERATURES COULD REALLY TANK TONIGHT. WENT SLIGHTLY
BELOW GUIDANCE FOR THE TYPICAL COLD SPOTS AS THINK THEY SHOULD BE
ABLE TO COME CLOSE TO ZERO. SINGLE DIGITS LOOK LIKELY ELSEWHERE.
925MB TEMPS ARE FAIRLY SIMILAR TO TODAY FOR SATURDAY...AND WITH
PLENTY OF SUN...HIGHS SHOULD TOP OUT CLOSE TO THOSE TODAY.

SATURDAY NIGHT AND SUNDAY...MODELS SHOW ANOTHER SHORTWAVE COMING OUT
OF SOUTH CENTRAL CANADA LATE SATURDAY...DROPPING SOUTHEAST INTO
WESTERN ILLINOIS BY 18Z SUNDAY. THIS SHORTWAVE WILL HELP TO KICK THE
TROUGH DROPPING INTO NEBRASKA EASTWARD...BUT ALSO BRING WITH IT A
SURGE OF DRY...COLDER AIR. BY 18Z SUNDAY...925MB TEMPS OVER THE
FORECAST AREA ARE AROUND -8C. PRIOR TO THE COLD AIR ARRIVAL...THERE
IS A CONCERN TO DEAL WITH WHICH IS THE SAME AS SATURDAY...LOW
STRATUS AND ANY LIGHT PRECIPITATION POSSIBLE WITH IT. IN THIS
CASE...MODELS HAVE AN AREA OF STRATUS COMING INTO THE FORECAST AREA
BEHIND A COLD FRONT ASSOCIATED WITH THE NEBRASKA TROUGH. VERY LITTLE
IF ANY ISENTROPIC LIFT IS NOTED WITHIN THIS STRATUS...SO THINK ANY
LIGHT PRECIPITATION POTENTIAL WOULD REMAIN OVER THE SOUTHEAST THIRD
OF THE AREA EARLY IN THE EVENING AHEAD OF THE FRONT. AGAIN...THIS IS
LIKELY TO BE FREEZING DRIZZLE GIVEN LACK OF ICE IN THE CLOUD. AFTER
MIDNIGHT...THERE ARE INDICATIONS OF A SECONDARY TROUGH WHICH IN
925MB TEMPS ALMOST LOOKS LIKE A WARM FRONT DROPPING SOUTH THROUGH
WISCONSIN. 270-275K ISENTROPIC LIFT PLOTS SHOW SOME LOW LEVEL LIFT
WITH THIS...LIKELY ENOUGH TO PRODUCE LIGHT PRECIPITATION. IT APPEARS
ICE WILL EXIST IN THE CLOUD THIS TIME...AIDED TOO BY MID CLOUDS
DROPPING SOUTH WITH THE SHORTWAVE COMING OUT OF SOUTH CENTRAL
CANADA. THUS...HAVE MAINTAINED A FLURRY MENTION. DRYING AND CLEARING
WILL TAKE PLACE SUNDAY MORNING FROM NORTHWEST TO SOUTHEAST. THE
INCREASE OF CLOUDS AND COLD ADVECTION WILL COUNTER-ACT EACH OTHER
SATURDAY NIGHT FOR LOWS...AND HAVE WENT WITH A BLEND OF GUIDANCE
SUGGESTING TEMPERATURES DROPPING INTO THE TEENS. SLIGHTLY COLDER DAY
EXPECTED ON SUNDAY GIVEN THE AFOREMENTIONED 925MB TEMPS.

SUNDAY NIGHT AND MONDAY...ATTENTION TURNS TO DEEP TROUGHING JUST OFF
THE WEST COAST OF NORTH AMERICA. OTHER THAN THE 04.12Z NAM...ALL
OTHER MODELS DEPICT THE TROUGH PROGRESSING EASTWARD INTO THE WESTERN
U.S. THROUGH THE WEEKEND AND SPLITTING INTO TWO. THE SOUTHERN
PART FORMS INTO A CUT-OFF LOW WHICH GETS STUCK IN THE SOUTHWESTERN
U.S.. THE NORTHERN PART IS A TROUGH THAT TRACKS ALONG THE
U.S./CANADIAN BORDER...BRINGING WITH IT A DYING COLD FRONT INTO
WESTERN MINNESOTA ON MONDAY. REGARDING THAT 04.12Z NAM...THE MODEL
HAS BEEN DISCOUNTED AS AN OUTLIER AS IT KEEPS A FULL SCALE TROUGH
AND MARCHES IT EASTWARD INTO THE PLAINS BY 00Z TUESDAY. NO MATTER
WHAT MODEL SOLUTION IS FOLLOWED...THIS PERIOD ENDS UP DRY WITH WARM
ADVECTION THROUGHOUT AS LOW LEVEL SOUTHWEST WINDS INCREASE AHEAD OF
THE APPROACHING SPLIT TROUGH AND DYING SURFACE COLD FRONT. 925MB
TEMPS CLIMB TO -2 TO -4C BY 18Z MONDAY WHILE 850MB TEMPS JUMP TO +2
TO +4C. THUS...MONDAY SHOULD END UP MUCH WARMER THAN SUNDAY WITH
MOST LOCATIONS TOPPING OUT FROM THE UPPER 20S TO MID 30S PER ECMWF
GUIDANCE. COLDEST LOCATIONS EXPECTED OVER SOUTHEAST MINNESOTA AND
NORTHEAST IOWA WITH HIGHER ALBEDO FROM SNOWPACK. LOWS SUNDAY NIGHT
LIKELY IN THE EVENING BEFORE SOUTHWEST WINDS PICK UP. FOLLOWED BLEND
OF GUIDANCE FOR LOWS.

.LONG TERM...MONDAY NIGHT THROUGH FRIDAY
233 PM CST FRI JAN 4 2013

FOCUS AS HAS BEEN THE PAST FEW DAYS IS ON THE UPPER LOW IN THE
SOUTHWESTERN U.S. ON MONDAY. YET AGAIN THERE IS A SPLIT IN SCENARIOS
AMONGST MODEL HANDLING OF THIS UPPER LOW:

1. THE 04.12Z CANADIAN REPRESENTS A VERY FAST SCENARIO...LIFTING IT
NORTHEAST ACROSS CHICAGO TUESDAY NIGHT. WE WOULD END UP WITH A LIGHT
TO MODERATE SNOWFALL ACROSS THE FORECAST AREA TUESDAY INTO TUESDAY
NIGHT SHOULD THIS VERIFY.
2. NEXT BEHIND THE CANADIAN IS THE 04.12Z GFS...LIFTING IT FROM
TEXAS ON TUESDAY INTO THE OHIO VALLEY ON WEDNESDAY. THIS SCENARIO
WOULD IT PAN OUT WOULD KEEP THE AREA DRY AND TEMPERATURES ABOVE
NORMAL THROUGH THURSDAY.
3. LASTLY...THE 04.12Z ECMWF/UKMET ARE EXTREMELY CONSISTENT WITH
PAST ECMWF RUNS...HAVING THE UPPER LOW CROSS NORTHERN MEXICO ON
TUESDAY...SHIFTING INTO TEXAS ON WEDNESDAY...THEN LIFTING INTO
ILLINOIS ON THURSDAY. THIS SCENARIO WOULD YIELD ABOVE NORMAL
TEMPERATURES THROUGH THURSDAY...WITH DRY WEATHER THROUGH WEDNESDAY
EVENING...RAIN TO MUCH OF THE AREA FOR LATE WEDNESDAY NIGHT INTO
THURSDAY...THEN TAPERING OFF TO A SNOW OR RAIN/SNOW MIX THURSDAY
NIGHT.

THE WHOLE PROBLEM RESULTING IN THE VARIOUS SCENARIOS STARTS ON
SUNDAY...REGARDING HOW QUICK THE DEEP UPPER TROUGH SPLITS INTO TWO
AND HOW FAST UPPER RIDGING CAN BUILD INTO THE PACIFIC NORTHWEST
BEHIND IT. PER HPC AND WANTING TO FOLLOW THE CONSISTENT AND GOOD
EXTENDED VERIFYING ECMWF...LEANED THE LONG TERM FORECAST MORE
TOWARDS THE ECMWF SOLUTION. THIS ALSO IS IN BETTER AGREEMENT WITH
THE PREVIOUS FORECAST. STILL HAVE ENDED UP KEEPING A SNOW OR
RAIN/SNOW MIX IN FOR WEDNESDAY NIGHT INTO THURSDAY MORNING...TO
HANDLE UNCERTAINTY ON THE TEMPERATURE RISE AND NOT WANTING TO
INTRODUCE FREEZING RAIN SINCE THAT TYPE SEEMS UNLIKELY.

AFTER THURSDAY...NEW DEEP TROUGHING IS FORECAST TO FORM BY ALL
MODELS OVER THE WESTERN U.S....WHICH IS ONE OF THE FEATURES THAT
HELPS KICK OUT THE UPPER LOW IN THE ECMWF/UKMET. SHORTWAVES EJECTING
OUT OF THE TROUGH REQUIRE CHANCES OF SNOW IN FOR FRIDAY. COOLER
TEMPERATURES ARE LIKELY AS WELL...THOUGH AT LEAST FOR FRIDAY STILL
CLOSE TO NORMAL AS THE DEEPER COLDER AIR ASSOCIATED WITH THE TROUGH
HOLDS OFF UNTIL THE WEEKEND.

&&

.AVIATION...TODAY AND SATURDAY
1138 AM CST FRI JAN 4 2013

VFR CONDITIONS WILL DOMINATE MOST OF THIS FORECAST. SPLIT UPPER FLOW
REGIMES BRING SOME UNCERTAINTY ON HOW IMPULSES IN BOTH FLOWS WILL
COME TOGETHER THIS WEEKEND. WHILE CLEAR/VFR CONDITIONS EXPECTED TO
PREVAIL INTO SATURDAY AFTERNOON...COULD SEE SOME LOWER CEILINGS
APPROACH FROM THE SOUTHWEST IN SOUTHERN BRANCH OF FLOW BUT THESE
MVFR CEILINGS WOULD MAINLY IMPACT AREAS ACROSS EASTERN IOWA INTO
SOUTHERN WISCONSIN. COULD ALSO SEE SOME MVFR CEILINGS BRUSH THROUGH
PARTS OF NORTH CENTRAL WISCONSIN OVERNIGHT IN NORTHWEST FLOW.
NONE OF THIS EXPECTED TO IMPACT TAF SITES THROUGH 18Z SATURDAY BUT
COULD SEE SOME SATURATION HEADING INTO SATURDAY EVENING WITH STRETCH
OF LOWER CEILINGS DEVELOPING.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
233 PM CST FRI JAN 4 2013

WI...NONE.
MN...NONE.
IA...NONE.

&&

$$

SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....SHEA