Forecast Discussions mentioning any of "HRRR" "RR" "RUC13" "RUC" received at GSD on 12/10/11

AREA FORECAST DISCUSSION

NWS DENVER CO

826 AM MST THU DEC 8 2011

.UPDATE...CURRENT WEATHER CAMS SHOW SNOW HAS BECOME MORE
WIDESPREAD IN THE MOUNTAINS EARLY THIS MORNING. ALREADY ONE HALF
TO ONE INCH OF SNOW AS FAR SOUTH AS COPPER MOUNTAIN. RADAR AND
SATELLITE TRENDS ALONG WITH SHORT RANGE MODEL GUIDANCE OF RUC AND
HRRR SHOWING THIS SNOW WILL CONTINUE THROUGH THE REST OF THE
MORNING AND THEN DECREASE. THE SAME CAN BE SAID OVER THE NORTHEAST
CORNER OF THE STATE WHERE BAND OF SNOW WILL DROP SLOWLY
SOUTH/SOUTHEAST ACROSS THAT AREA. THE CHANCE OF SNOW WILL DECREASE
RATHER RAPIDLY TO THE SOUTH AND WEST TOWARD DENVER WHERE LOW LEVEL
AIR IS SIGNIFICANTLY DRIER AND LARGE SCALE SUBSIDENCE WILL TAKE
HOLD EARLIER IN THE AFTERNOON.

.AVIATION...GOING FORECAST ON TRACK WITH ONLY A CHANCE OF LOWER
MVFR CEILINGS DEVELOPING WITH THE WEAK FRONTAL PUSH. THIS WEAK
FRONT IS STILL EXPECTED TO REACH THE FRONT RANGE AIRPORTS AROUND
18Z WITH ONLY A SLIGHT WIND SHIFT FROM AN EASTERLY DIRECTION.

.PREV DISCUSSION... /ISSUED 310 AM MST THU DEC 8 2011/

LONG TERM...THERE WILL BE A DECREASING NORTHWEST FLOW ALOFT ON
FRIDAY WITH A DRYING AND SLOW WARMING TREND ACROSS COLORADO. THIS
TREND WILL CONTINUE THROUGH THE WEEKEND AS THE GREAT BASIN RIDGE OF
HIGH PRESSURE SHIFTS OVER COLORADO AND WEAKENS A BIT. TEMPERATURES
WILL WARM TO AROUND SEASONABLE NORMALS WITH PLENTY OF SUNSHINE AND
DRY CONDITIONS.

BY EARLY NEXT WEEK...SPLIT FLOW PATTERN DEVELOPS OVER MUCH OF THE
WEST WITH CLOSED LOW DEVELOPING ACROSS SOUTHERN CALIFORNIA ON MONDAY
WHILE WEAKER NORTHERN BRANCH STRETCHES A WEAK TROF ACROSS THE
NORTHERN PLAINS STATES AND BRUSHES NORTHERN COLORADO WITH A WEAK
FRONT AND COOLER TEMPERATURES. THIS PATTERN EVOLUTION SHOWS QUITE A
BIT OF UNCERTAINTY AS THE EUROPEAN/GEM SOLUTIONS ARE DEEPER WITH THE
LOW YET EJECTS IT FURTHER NORTH INTO COLORADO ON WEDNESDAY WHILE THE
GFS SOLUTION HAS THE LOW ACROSS NEW MEXICO AND TEXAS. THE EUROPEAN
TRAJECTORY WOULD FAVOR A CHANCE OF SNOW AND COOLER TEMPS WHERE VERY
LITTLE EFFECT WOULD BE FELT FROM THE FURTHER SOUTH GFS SOLUTIONS.
GFS ENSEMBLE MEMBERS NOT MUCH HELP AS SOLUTIONS ARE ALL OVER THE
BOARD. THIS ALL MEANS VERY LITTLE CHANGES TO THE OUT DAYS IN THE
LONG TERM FORECAST. WILL KEEP A SLIGHT CHANCE OF SNOW OVER THE
ENTIRE CWA FOR LATE TUESDAY AND WEDNESDAY.

AVIATION...A CDFNT WILL MOVE ACROSS NERN CO LATER THIS MORNING AND
AFTN HOWEVER BOTH THE NAM AND HRRR KEEP THE MAIN PUSH OVER THE
PLAINS AND KIND OF BACK DOOR THE FNT INTO THE FNT RANGE BY EARLY TO
MID AFTN WITH VERY WK UPSLOPE. OVERALL IT LOOKS LIKE POTENTIAL FOR
LOW CEILINGS AND SOME FOG WILL REMAIN LOW THRU 18Z HOWEVER THEY
COULD EVENTUALLY BACK IN FM THE NE AND E BY MID TO LATE AFTN
ALTHOUGH NEITHER THE LATEST NAM OR HRRR EVER SHOW THEM AFFECTING THE
AIRPORT. FOR NOW WILL GO WITH A TEMPO GROUP AS CONFIDENCE IS NOT
VERY HIGH. MEANWHILE THERE IS A 10% CHANCE OF A FEW SNOW FLURRIES
THIS AFTN AS A WK TROUGH MOVES ACROSS. WINDS EARLY THIS MORNING
WILL BE LIGHT WLY AND THEN BECOME LIGHT SLY BY 15Z. BY EARLY AFTN
AS THE FNT BACKDOORS IN THE WINDS WILL BECOME LIGHT ESE BASED ON THE
LATEST HRRR.

FOR THIS EVENING COULD STILL SEE SOME POTENTIAL FOR LOW CLOUDS AND
FOG ALTHOUGH NAM KEEPS BEST CHC TO THE NORTH AND EAST OF AIRPORT.
AFTER 06Z THE LOW LEVEL WINDS BECOME MORE WSW WHICH SHOULD KEEP THE
LOW CLOUDS EAST OF THE AIRPORT.

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

SHORT TERM...BARJENBRUCH
LONG TERM....ENTREKIN
AVIATION...BARJENBRUCH

AREA FORECAST DISCUSSION

NWS DENVER CO

310 AM MST THU DEC 8 2011

SHORT TERM...A WK UPPER LEVEL TROUGH WILL MOVE SE ACROSS THE AREA
TODAY WITH SOME VERY WK MID LVL QG ASCENT. CROSS-SECTIONS SHOW
ENOUGH MOISTURE WILL BE AVAILABLE FOR A CHC OF SOME LIGHT SNOW IN
THE MTNS MAINLY OVER ZNS 31 AND 33. EAST OF THE MTNS A CDFNT WILL
MOVE ACROSS NERN CO LATER THIS MORNING THRU THE AFTN HOURS HOWEVER
UPSLOPE FLOW WILL BE WK. MEANWHILE THE FAR NERN PLAINS WILL ALSO BE
AFFECTED BY A WK UPPER LEVEL JET WHICH COULD LEAD TO A CHC OF LIGHT
SNOW THRU THE AFTN HOURS MAINLY FM STERLING EASTWARD. ELSEWHERE
ACROSS THE PLAINS THERE WILL ONLY BE A SLIGHT CHC OF -SHSN.
SOUNDINGS SHOW AIRMASS WILL BE COLD ENOUGH FOR PCPN TO FALL AS SNOW
SO WILL NOT MENTION ANY FREEZING DRIZZLE ACROSS NERN CO. HIGHS THIS
AFTN WILL GENERALLY BE IN THE 25 TO 30 DEGREE RANGE ACROSS NERN CO
BEHIND THE CDFNT AS COLD SFC HIGH PRESSURE BUILDS INTO THE RGN.

FOR TONIGHT WILL HAVE A DRY FCST AS THE WK UPPER LEVEL TROUGH MOVES
AWAY FM THE AREA. SOME FOG COULD DVLP OVER THE PLAINS THIS EVENING
AND LINGER OVERNIGHT.

.LONG TERM...THERE WILL BE A DECREASING NORTHWEST FLOW ALOFT ON
FRIDAY WITH A DRYING AND SLOW WARMING TREND ACROSS COLORADO. THIS
TREND WILL CONTINUE THROUGH THE WEEKEND AS THE GREAT BASIN RIDGE OF
HIGH PRESSURE SHIFTS OVER COLORADO AND WEAKENS A BIT. TEMPERATURES
WILL WARM TO AROUND SEASONABLE NORMALS WITH PLENTY OF SUNSHINE AND
DRY CONDITIONS.

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

SHORT TERM...RPK
LONG TERM....SWE
AVIATION...RPK

AREA FORECAST DISCUSSION

NWS ALBANY NY

1245 AM EST THU DEC 8 2011

.SYNOPSIS...
A STORM SYSTEM WILL LIFT NORTHEAST FROM THE DELMARVA REGION THIS
EVENING...TO THE EAST END OF LONG ISLAND AROUND MIDNIGHT...AND
THEN INTO THE GULF OF MAINE THURSDAY MORNING. THIS STORM TRACK
WILL RESULT IN RAIN CHANGING TO SNOW THIS EVENING ACROSS MUCH OF
THE REGION WITH SIGNIFICANT SNOWFALL ACCUMULATIONS OVERNIGHT IN
MANY AREAS. THE HEAVIEST SNOW IS EXPECTED TO FALL ACROSS THE
NORTHERN TACONICS...EASTERN CATSKILLS...BERKSHIRES AND SOUTHERN
GREEN MOUNTAINS. HEAVY RAIN WILL CONTINUE TO FALL OVERNIGHT ACROSS
THE MID HUDSON VALLEY AND LITCHFIELD HILLS.

.NEAR TERM /THROUGH THURSDAY/...
AS OF 930PM RADAR FSI CROSS SECTIONS AND SPOTTER REPORTS HAVE RAIN
CHANGING TO SNOW AROUND THE GREATER CAPITAL DISTRICT. THIS IS
RUNNING AN HOUR OR TWO BEHIND GRIDS AND MADE MINOR CHANGES. THIS
PROCESS WILL RAPIDLY CHANGE RAIN OVER TO SNOW IN NEXT 1-2 HOURS.
00UTC NAM IN LINE WITH PVS QPF AND THINKING. NO DEPARTURES THERE.
ONCE PCPN CHANGES OVER BURST OF SNOW FOR SEVERAL HOURS IN MASSIVE
TILTED FRONTOGENESIS AS MESOSCALE BAND HAS SET UP FM SW VT TO
CATSKILLS (CSTAR) WHILE PCPN MAY BE CHANGING OVER 1-2 HOURS
LATER...DONT THINK IT WILL SIGNIFICANTLY ALTER CURRENT THINKING ON
AMOUNTS OR HEADLINES GIVEN CHARACTER AND FORCING OF THE SNOW
OVERNIGHT.

ALL 3 HOUR PRESSURE MAX FALLS ARE NOW OFFSHORE NJ/DELMARVA. RAPID
DEEPENING WILL OCCUR NEXT FEW HOURS AS 500HPA SHORT WAVE INTERACT
WITH STRONG BAROCLINIC ZONE ALONG COAST.

AS OF 7PM...NOT MAKING ANY CHANGES ATTM. AWAITING CHANGE OVER TO
SNOW. ON ALB 00UTC ALB SOUNDING +4C WARM NOSE REMAINS AT 3500 MSL.
FSI CROSS SECTIONS CAPPI INDICATE BRIGHT BAND LOWERING TO GROUND IN
MONTGOMERY/SCHOHARIE COUNTIES...BUT ONLY ONE REPORT OF SNOW IN
WEST SCHOHARIE COUNTY AN HOUR AGO.

BANDLETS (CSTAR III) HAVE SET UP ACROSS RGN WITH SOME ALONG BRIGHT
BAND AXISES AND OTHERS IN RN TO +RN AREAS. 18UTC NAM/GFS SHOW ALL
THE RIGHT FEATURES FOR FORMATION OF A MAJOR BAND OVER FCA. 20UVM
IN MAX DENDRITIC GROWN ZONE BY 03UTC...STRONG TILTED FRONTOGENESIS
AND EPV. SO THE STAGE IS SET...JUST AWAITING THE ARRIVAL OF THE
COLDER AIR OR ITS DYNAMIC CREATION.

SFC PRES FALLS HAVE SHIFTED TO NJ-DELMARVA COAST BUT 3HR VALUES
REMAIN REMAIN ON ORDER OF 4-6MB. WX WATCH CONTINUES.

WINTER STORM WARNINGS ARE IN EFFECT FOR TONIGHT FOR THE EASTERN
CATSKILLS...NORTHERN TACONICS...BERKSHIRES AND SOUTHERN GREEN
MOUNTAINS AND WINTER WEATHER ADVISORIES IN EFFECT FOR THE
SOUTHEAST ADIRONDACKS...LAKE GEORGE SARATOGA REGION...EASTERN
MOHAWK VALLEY...SACANDAGA REGION...GREATER CAPITAL DISTRICT AND
CENTRAL TACONICS. A FLOOD WATCH IS IN EFFECT THROUGH THURSDAY
MORNING FOR THE MID HUDSON VALLEY...SOUTHERN TACONICS AND
LITCHFIELD HILLS.

SNOWFALL ACCUMULATIONS ARE GENERALLY EXPECTED TO BE 3 TO 8 INCHES
IN THE ADVISORY AREA AND 5 TO 12 INCHES IN THE WARNING AREA EXCEPT
ACROSS THE CENTRAL AND SOUTHEAST CATSKILLS...NORTHERN BERKSHIRES
AND HIGHER TERRAIN OF THE SOUTHERN GREEN MOUNTAINS WHERE 8 TO 16
INCHES OF SNOW IS EXPECTED. TOTAL RAINFALL AMOUNTS IN THE FLOOD
WATCH AREA ARE EXPECTED TO BE IN THE 1.75 TO 2.25 INCH RANGE.

AS OF 530 PM EST...CLOUD TOPS CONTINUE TO COOL ACROSS THE FA WITH
21Z KALB SOUNDING INDICATING A WARM TONGUE OF 4C AT AROUND 875 MB
WITH THE FREEZING LEVEL AT AROUND 775 MB OR 6.6 KFT. HAVE RECEIVED
A REPORT OF 1 INCH OF SNOW THUS FAR IN CHARLOTTEVILLE IN SCHOHARIE
COUNTY WITH HEAVY WET SNOW AND A TEMP OF 36 DEGREES AT AN
ELEVATION OF AROUND 1500 FEET. EXPECT A RAPID CHANGEOVER TO SNOW
THIS EVENING ACROSS MUCH OF THE FA MAINLY BETWEEN 00Z AND 03Z WITH
VERY HEAVY SNOW EXPECTED TO FALL DURING MUCH OF THE NIGHT BEFORE
TAPERING OFF LATE. THE ONLY AREAS WHICH ARE NOT EXPECTED TO
RECEIVE MUCH SNOW ARE FAR NORTHWEST PORTIONS OF THE FA INCLUDING
THE WESTERN ADIRONDACKS AND WESTERN MOHAWK VALLEY WHERE VERY
LITTLE QPF EXPECTED...NORTHERN FRINGE OF PCPN SHIELD AND FAR
SOUTHEAST PORTION OF FA WHICH WILL REMAIN TOO WARM FOR MUCH IN THE
WAY OF SNOW MAINLY FROM THE MID HUDSON VALLEY EAST TO THE
LITCHFIELD HILLS WHERE A FLOOD WATCH IS IN EFFECT.

MANY FAVORABLE FACTORS FOR HEAVY SNOW ARE IN PLACE ACROSS MUCH OF
THE FA WITH THE MOST SIGNIFICANT FACTORS BEING IMPRESSIVE
FRONTOGENESIS H8-H7 EXTENDING FROM THE CATSKILLS NORTHEAST TO
SOUTHERN VERMONT AT 00Z AND THEN SHIFTING TO AN ORIENTATION FROM
JUST EAST OF THE CAPITAL DISTRICT THROUGH THROUGH THE NORTHERN
BERKSHIRES INTO SOUTHERN VERMONT AT 06Z. AS THE EVENING WEARS ON
THE SNOW GROWTH REGION BECOMES INCREASINGLY MORE FAVORABLE WITH
THE -12 TO -18 C TEMP SLICING THROUGH A REGION OF +20 UBAR/SEC. IN
ADDITION IMPRESSIVE EPV EXISTS IN LOWER LEVELS ESPECIALLY BTWN 00Z
AND 06Z. THE LATEST HRRR COL MAX REFLECTIVITY ALSO INDICATES
IMPRESSIVE BANDED PCPN ESPECIALLY ACROSS THE HIGHER TERRAIN IN THE
WARNING AREA BETWEEN 03Z AND 06Z WITH THE BACK EDGE OF THE PCPN
SHIELD EXITING THE FA FROM WEST TO EAST BETWEEN 08Z AND 10Z.
EXPECT LOW TEMPS TONIGHT TO RANGE FROM THE MID 20S NORTHWEST TO
MID 30S FAR SOUTHEAST.

ON THURSDAY EXPECT IMPROVING CONDITIONS WITH HIGH PRESSURE MOVING
IN AND MAINLY DRY CONDITIONS WITH HIGHS RANGING FROM THE UPPER
20S TO LOWER 30S NORTHWEST TO LOWER 40S FAR SOUTHEAST.

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
THU NT...BACKING LOW LEVEL WINDS SHOULD ALLOW ANY LINGERING SNOW
BANDS/SNOW SHOWERS TO SHIFT NORTHWARD INTO THE WESTERN
ADIRONDACKS...WITH ADDITIONAL ACCUMS POSSIBLE BEFORE INVERSION
HEIGHTS LOWER AND DIMINISH INTENSITY OF ANY SNOWBANDS.
ELSEWHERE...INITIALLY CLEAR TO PARTLY CLOUDY SKIES SHOULD BECOME
MOSTLY CLOUDY LATER AT NIGHT AS MID LEVEL ISENTROPIC LIFT INCREASES
AHEAD OF NEXT APPROACHING SHORTWAVE. EXPECT MINS TO FALL INTO THE
TEENS AND 20S...WARMEST ACROSS VALLEY REGIONS.

FRI-SAT...UPPER LEVEL TROUGH WILL APPROACH FROM THE W...AND PASS
ACROSS FRI NT. A SFC COLD FRONT ASSOCIATED WITH THIS FEATURE WILL
CROSS THE REGION LATE FRI OR FRI EVE...PRECEDED AND ACCOMPANIED BY
SNOW SHOWERS. THEN...BEHIND THE FRONT...BANDS OF SNOW SHOWERS AND
POSSIBLE SNOW SQUALLS WILL BE POSSIBLE...INITIALLY FAVORING PORTIONS
OF THE WESTERN MOHAWK VALLEY/SCHOHARIE VALLEY...THEN GRADUALLY
SHIFTING NORTHWARD INTO THE WESTERN ADIRONDACKS BY SAT. THERE IS
SOME POTENTIAL FOR LOCALLY HEAVY SNOWFALL AMTS WITHIN SOME OF THESE
BANDS...AND WILL MENTION THIS POSSIBILITY IN THE HWO...WITH GREATEST
THREAT ACROSS THE WESTERN ADIRONDACKS. EXPECT FRI MAXES TO REACH THE
30S IN MOST AREAS...EXCEPT AROUND OR INTO THE LOWER 40S WITHIN THE
VALLEYS...WITH 20S ACROSS HIGHER ELEVATIONS. COLDER AIR BEHIND THE
FRONT WILL MOVE IN FOR FRI NT AND SAT...WITH FRI NT MINS IN THE
TEENS AND LOWER 20S...AND SAT MAXES MAINLY IN THE 30S WITHIN
VALLEYS...AND 20S ACROSS HIGHER ELEVATIONS.

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THIS PERIOD WILL BE FAIRLY QUIET AS HIGH PRESSURE BUILDS INTO THE
MID ATLANTIC REGION SATURDAY NIGHT AND DOMINATES OUR WEATHER INTO
THE EARLY PART OF THE COMING WEEK. A CHANCE OF SOME LAKE ENHANCED
SNOW SHOWERS SATURDAY NIGHT...THEN DRY UNTIL TUESDAY NIGHT WHEN A
WEAK BOUNDARY BRINGS ABOUT SOME SNOW AND RAIN SHOWERS WEST OF THE
HUDSON VALLEY WEDNESDAY.

THE PERIOD STARTS OFF CHILLY...LOWS FROM AROUND 10 TO 20 ABOVE ON
SUNDAY MORNING...WITH HIGHS SUNDAY ONLY IN THE UPPER 20S TO THE
MID 30S. TEMPERATURES WILL GRADUALLY MODERATE WITH HIGHS RISING
TO THE UPPER 30S AND LOWER 40S BY TUESDAY AFTERNOON.

FOR THE MOST PART...USED HPC GUIDANCE TO POPULATE THE GRIDS.

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 0530Z...PCPN HAS CHANGED OVER TO SNOW AT THE KGFL/KALB/KPOU
TAF SITES. EXPECT THE SNOW AND MAINLY IFR CONDITIONS TO CONTINUE
UNTIL AROUND 08Z TO 09Z...WITH A RAPID IMPROVEMENT TO VFR CONDITIONS
AFTER 09Z. VFR CONDITIONS THEREAFTER UNTIL THE END OF THE TAF PERIOD
AT 06Z FRIDAY.

NORTHERLY WINDS AT 5 TO 15 KTS WITH SOME GUSTS TO 20 KTS POSSIBLE AT
THE TAF SITES (PRIMARILY KALB/KPOU)...THEN BECOMING NORTHWEST AFTER
THE SNOW ENDS AND INCREASING TO 10 TO 15 KTS BY MID MORNING WITH
GUSTS OF 20 TO 25 KTS. BY LATE IN THE AFTERNOON THE WINDS WILL
SUBSIDE TO 10 KTS OR LESS AN DSHIFT TO THE SOUTHWEST...THEN LIGHT
SOUTH OR SOUTHWEST WINDS AFTER 00Z FRIDAY.

OUTLOOK...
LATE THU NT-SAT...MAINLY VFR...SLIGHT CHC -SHSN. BREEZY.
SUN-MON...VFR...NO SIG WX.

.HYDROLOGY...
A SIGNIFICANT MIXED PRECIPITATION EVENT WAS OCCURRING ACROSS THE
REGION WITH STORM TOTAL LIQUID AMOUNTS FROM LESS THAN A QUARTER
INCH IN NORTHERN HERKIMER COUNTY TO A LITTLE OVER TWO INCHES IN
THE LOWER HUDSON VALLEY OF NEW YORK AND THE LITCHFIELD HILLS OF
CONNECTICUT. OVER COOLER REGIONS SUCH AS THE HIGHER ELEVATIONS OF
THE CATSKILLS...BERKSHIRES...AND GREEN MOUNTAINS OF SOUTHERN
VERMONT A SUBSTANTIAL AMOUNT OF THIS PRECIPITATION IS FORECAST
TO COME AS SNOW. ACROSS OUR SOUTHERNMOST COUNTIES...EASTERN ULSTER
DUTCHESS...AND LITCHFIELD...MOST OF THE PRECIPITATION WILL
COME AS RAIN AND LOCALLY HEAVY AMOUNTS MAY AMOUNT TO ENOUGH TO
RESULT IN SOME MINOR FLOODING OF ROADS AND PARKING AREAS AND
CAUSE RISES OF SEVERAL FEET ON RIVERS AND STREAMS.

FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.

.ALY WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH UNTIL 9 AM EST THURSDAY FOR CTZ001-013.
NY...WINTER STORM WARNING UNTIL 6 AM EST THURSDAY FOR NYZ047-051-
054-058-063.
WINTER WEATHER ADVISORY UNTIL 6 AM EST THURSDAY FOR NYZ039>043-
048>050-052-053-059>061-082>084.
FLOOD WATCH UNTIL 9 AM EST THURSDAY FOR NYZ064>066.
MA...WINTER STORM WARNING UNTIL 6 AM EST THURSDAY FOR MAZ001-025.
VT...WINTER STORM WARNING UNTIL 6 AM EST THURSDAY FOR VTZ013-014.
WINTER WEATHER ADVISORY UNTIL 6 AM EST THURSDAY FOR VTZ015.

$$
SYNOPSIS...11
NEAR TERM...11/SNYDER
SHORT TERM...KL
LONG TERM...RCK
AVIATION...GJM
HYDROLOGY...RCK

AREA FORECAST DISCUSSION

NWS JACKSONVILLE FL

952 AM EST THU DEC 8 2011

.UPDATE...WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW BROAD MID-
UPPER TROUGHING ACROSS THE SRN CONUS WITH UPPER LEVEL DISTURBANCE
MOVING ACROSS THE OK/TX/AR AREA. SHOULD SEE ASSOCD HIGH CLOUDS
MOVE ACROSS OUR AREA IN THE AFTERNOON AND TONIGHT.
SFC HIGH IS SITUATED ACROSS THE LOWER MS VALLEY TO ERN TN WITH
TYPICAL INVERTED TROUGHING NOTED ALONG OUR COAST. LLVL FLOW IS NLY
BUT JUST ABOVE THE SFC HAS TURNED NE. BROKEN-OVERCAST STRATOCU
CLOUDS AROUND 2-3 KFT HAVE ADVANCED WELL INLAND NOW TO DUVAL
COUNTY SW TO MARION COUNTY. THESE CLOUDS ASSOCD WITH COLDER
AIRMASS MOVING OVER WARM ATLC WATERS/WEAK ISENTROPIC LIFT AND
LLVL CONVERGENCE. HAVE ADJUSTED SKY CONDS UP TO MOSTLY CLOUDY AND
TWEAKED TEMPS DOWN OVER THE SE ZONES. A FEW SPRINKLES POSSIBLE
LATER IN THE AFTN NEAR THE COAST S OF DUVAL BUT THINK WILL LEAVE
OUT FOR NOW DUE TO SHALLOW NATURE OF THIS MOISTURE.

.AVIATION...MVFR CIGS AROUND FL020-030 EXPECTED FOR JAX/CRG/VQQ
AND GNV FOR DURATION OF THE DAY AS STRATOCU MOVES INLAND. PROBABLY
LOOKING AT MVFR DEVELOPING AT SSI AROUND THE 16Z-18Z TIME FRAME SO
AMENDMENTS TO FOLLOW. OUTLOOK FOR TONIGHT CALLS FOR MVFR CIGS WITH
THE BEST CHANCES COASTAL COUNTY TAFS.

.MARINE...NLY WINDS AT 15-20 KT AT 41012 WITH SEAS OF 5 FT. THIS
IS SLIGHTLY BELOW CURRENT WINDS SO WILL ADJUST WINDS A BIT DOWNWARD
REST OF TODAY BUT ADVISORY FOR OFFSHORE LOOKS GOOD...AND WINDS
ANTICIPATED TO BE AROUND THE 15-20KT RANGE NEARSHORE.

RIP CURRENTS: MODERATE RISK AS WINDS SHIFTING TO NE AND LOW E
SWELLS.

.PRELIMINARY POINT TEMPS/POPS...
AMG 59 35 63 42 / 0 0 10 10
SSI 58 47 64 49 / 0 10 10 20
JAX 60 44 67 47 / 0 10 10 10
SGJ 60 51 68 54 / 10 20 10 20
GNV 61 42 68 48 / 0 10 10 10
OCF 63 46 71 51 / 0 10 10 10

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR ALTAMAHA
SOUND GA TO FERNANDINA BEACH FL 20 NM TO 60 NM OFFSHORE-
FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM OFFSHORE-
ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM OFFSHORE.

SHASHY/WALKER

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

304 AM CST THU DEC 8 2011

.DISCUSSION...
856 PM CST

SMALL UPDATES HAVE BEEN MADE FOR THE REMAINDER OF TONIGHTS
FORECAST...WITH ATTENTION TURNING TO THURSDAY NIGHTS SNOW
POTENTIAL.

VARIABLE CLOUD COVERAGE BY OVERNIGHT IS MAKING IT CHALLENGING ON
THE TEMPERATURE FORECAST. WITH AN INITIAL COLD FRONT CONTINUING
TO LOSE DEFINITION AS IT DRAPES INTO NORTHERN IL...LOW CLOUDS HAVE
DIMINISHED IN COVERAGE. SATELLITE TRENDS AND RUC SOUNDINGS ACROSS
NORTHEAST IL INDICATE TEMPORARY SCATTERED CLOUDS ARE LIKELY TO
CONTINUE TO PROPAGATE SOUTHEAST. CLOUDS ALONG THE MID-LEVEL
BAROCLINIC ZONE SEEN AT 700 MB ON THIS EVENINGS UPPER AIR ANALYSIS
WILL ALSO CONTINUE TO SLOWLY FILTER INTO THE AREA THROUGH THU
MORNING. SO WILL CONTINUE TO ADJUST SKY TRENDS...BUT ALL IN ALL
VARIABLE TO PARTLY CLOUDY WORDING IS PROBABLY THE BEST BET. EVEN
THOUGH THE HOURLY TREND WILL DEPEND HEAVILY ON HOW ANY CLOUDS
UNDULATE IN COVERAGE...LOW TEMPERATURES STILL LOOK ON TRACK.
SCATTERED MID-TEENS ARE FORECAST TOWARDS ROCKFORD AND
STERLING...WITH LOWER TO MID 20S TOWARDS THE LAKE AND INTO
NORTHWEST IN.

A LOOK AT THE LATEST GUIDANCE...08.00 NAM AND 07.21 SREF...AS WELL
AS UPSTREAM TRENDS ARE STARTING TO SUPPORT THE LIKELY SCENARIO
THAT A MINOR ACCUMULATING SNOW EVENT WILL BE SEEN IN THE FORECAST
AREA...ESPECIALLY THE SOUTHEAST QUARTER TO THIRD. THE UPPER AIR
ANALYSES THIS EVENING DEPICTED THE STRONG UPPER JET /OVER 120 KTS
AT UNR/ HEADING TOWARDS THE AREA WHICH WILL PROVIDE MORE
CONCENTRATED UPPER SUPPORT DURING TUE AFTERNOON AND NIGHT.
SATURATION AND QG FORCING WITH THE WAVE WILL NOT ARRIVE INTO
PARTS OF OUR AREA UNTIL THE NIGHT...LIKELY BY 03Z. THE NEW NAM
OUTPUT INDICATES MIXING RATIOS NEAR 2 G/KG ON THE FAVORED SURFACES
WHERE LIFT IS OCCURRING INTO THE FAR SOUTHEAST...AND THAT IS
NEARLY COINCIDENT WITH THE DENDRITIC GROWTH AREA. WHILE TOP-DOWN
METHODS ON THE NAM SOUNDINGS WARM SOME ON THE WAY DOWN...RATIOS
STILL LOOK TO BE ON THE HIGHER SIDE AS INDICATED BY EVEN THE
PRIOR NAM RUNS. THE SREF GUIDANCE HAS BECOME MORE FOCUSED ON ITS
SNOW PROBABILITIES...INDICATING A RIBBON ACROSS THE SOUTHEAST
/GIBSON CITY TO RENSSELAER/ WHERE OVER ONE INCH OF SNOW IS
FORECAST BY THE MEAN OF THE MEMBERS. EVEN THE PRIOR RUNS OF THESE
MODELS AND THE GFS...EC...AND NMM WRF...INDICATE THE FAR SOUTHERN
TIER OF COUNTIES TO SEE SNOW...AND COULD ENVISION BASED ON RATIOS
AND RECENTLY COOLED GROUND TEMPERATURES THAT ONE TO TWO INCH
ACCUMULATIONS ARE POSSIBLE. MINOR ACCUMULATIONS OF A COUPLE TENTHS
AS FAR NORTH AS CHICAGO CANNOT BE RULED OUT DEPENDING ON IF THE
ATMOSPHERE CAN SATURATE...AND LIGHT AMOUNTS ARE FORECAST THAT FAR
NORTH BY THE 18.00 NAM. WILL RE-ISSUE AN SPS TO HIGHLIGHT FOR NOW
AND BRIEF THE OVERNIGHT SHIFT.

MTF

.AVIATION...

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

* ISOLATED THREAT FOR -SN THURSDAY EVENING

SHEA

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

LIGHT WESTERLY WINDS WILL CONTINUE OVERNIGHT AS AN APPROACHING
NORTHERN HIGH PLAINS SYSTEM AND ANOTHER COLD FRONT DROPS SOUTHEAST
ACROSS WISCONSIN DURING THE DAY TODAY. THIS SYSTEM IS EXPECTED TO
PRODUCE SOME LIGHT SNOWFALL BUT THE ZONE OF BEST FORCING AT THIS
POINT LOOKS TO BE ALONG A NORTHERN MISSOURI...CENTRAL
IL...NORTHEAST INDINANA AXIS SO THREAT OF ANY PRECIPITATION AT
THE LOCAL TERMINALS QUITE SMALL.

SHEA

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

* HIGH CONFIDENCE IN ALL ELEMENTS

SHEA

//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...

FRIDAY...VFR.

SATURDAY...VFR.

SUNDAY...VFR.

MONDAY...VFR INTO EVENING...SLGT CHC -SN PRODUCING MVFR CIGS
AND/OR VSBYS OVERNIGHT.

TUESDAY...MVFR CIGS POSSIBLE.

TRS

.MARINE...
305 AM CST

A PROLONGED PERIOD OF GENERALLY WEST WINDS IS SETTING UP FOLLOWING
THE PASSAGE OF A COLD FRONT. ANOTHER SURGE OF COLD AIR ASSOCIATED
WITH A SECONDARY COLD FRONT WILL PUSH ACROSS THE LAKE LATER
TODAY...KEEPING WESTERLY WINDS IN THE 25 TO 30 KT INTO SATURDAY.
AN UPPER LEVEL TROUGH CROSSING THE GREAT LAKES REGION FRIDAY AND
FRIDAY NIGHT WILL BRING VERY COLD AIR ALOFT OVER LAKE MICHIGAN.
COMBINED WITH RELATIVELY WARMER LAKE SURFACE WATER...A VERY
UNSTABLE ENVIRONMENT WILL SET UP OVER THE LAKE...BRINGING A CHANCE
FOR WATERSPOUTS.

BY SATURDAY...WINDS WILL SHIFT SOUTHWESTERLY AS HIGH PRESSURE
BUILDS ACROSS THE OHIO VALLEY WHILE A WEAK LOW PRESSURE SYSTEM
TRACKS ACROSS THE UPPER GREAT LAKES. THE HIGH WILL BE FAR ENOUGH
TO THE SOUTH THAT WINDS WILL REMAIN AROUND 30 KT THROUGH THE
WEEKEND.

KREIN

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE BURNS HARBOR TO MICHIGAN
CITY IN UNTIL 10 AM SATURDAY.

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

205 AM CST THU DEC 8 2011

.DISCUSSION...
856 PM CST

SMALL UPDATES HAVE BEEN MADE FOR THE REMAINDER OF TONIGHTS
FORECAST...WITH ATTENTION TURNING TO THURSDAY NIGHTS SNOW
POTENTIAL.

MTF

.AVIATION...

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

* ISOLATED THREAT FOR -SN THURSDAY EVENING

SHEA

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

SHEA

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

* HIGH CONFIDENCE IN ALL ELEMENTS

SHEA

//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...

FRIDAY...VFR.

SATURDAY...VFR.

SUNDAY...VFR.

MONDAY...VFR INTO EVENING...SLGT CHC -SN PRODUCING MVFR CIGS
AND/OR VSBYS OVERNIGHT.

TUESDAY...MVFR CIGS POSSIBLE.

TRS

.MARINE...
157 PM CST

A COLD FRONT MOVING ACROSS LAKE SUPERIOR AND WISCONSIN THIS
AFTERNOON WILL MOVE ACROSS LAKE MICHIGAN LATER THIS AFTERNOON AND
EVENING. THIS WILL HELP KEEP THE WINDS AROUND 25 TO 30 KT TONIGHT AS
THE WINDS BECOME NORTHWESTERLY. A PROLONGED PERIOD OF BRISK WEST TO
NORTHWESTERLY WINDS IS EXPECTED INTO SATURDAY AS HIGH PRESSURE
MOVING FROM THE PLAINS EASTWARD ACROSS THE MID MISSISSIPPI
VALLEY...WILL CONTINUE TO PRODUCE A DECENT PRESSURE GRADIENT ACROSS
THE GREAT LAKES.

LATER SATURDAY THE WINDS LOOK TO SWITCH OUT OF THE SOUTHWEST AND
INCREASE TO AROUND 30 KT AGAIN AS THE SURFACE HIGH SHIFTS ACROSS THE
OHIO VALLEY AND ANOTHER AREA OF LOW PRESSURE MOVES ACROSS THE
PRAIRIE PROVIDENCES OF CANADA. IT APPEARS THAT THESE SOUTHWESTERLY
WINDS WILL CONTINUE INTO EARLY NEXT WEEK AS THE SURFACE HIGH
CONTINUES TO DOMINATE ACROSS EASTERN CONUS. THERE COULD EVEN BE A
PERIOD OF LOW END GALE FORCE WINDS DURING THIS PERIOD.

KJB

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO BURNS HARBOR UNTIL
10 PM THURSDAY.

SMALL CRAFT ADVISORY...NEARSHORE BURNS HARBOR TO MICHIGAN CITY IN UNTIL 10 AM SATURDAY.

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

1227 AM CST THU DEC 8 2011

.DISCUSSION...
856 PM CST

SMALL UPDATES HAVE BEEN MADE FOR THE REMAINDER OF TONIGHTS
FORECAST...WITH ATTENTION TURNING TO THURSDAY NIGHTS SNOW
POTENTIAL.

MTF

.AVIATION...

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

* ISOLATED THREAT FOR -SN THURSDAY EVENING

SHEA

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

SHEA

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

* HIGH CONFIDENCE IN ALL ELEMENTS

SHEA

//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
*
FRIDAY...VFR.

SATURDAY...VFR.

SUNDAY...VFR.

MONDAY...VFR INTO EVENING...SLGT CHC -SN PRODUCING MVFR CIGS
AND/OR VSBYS OVERNIGHT.

TUESDAY...MVFR CIGS POSSIBLE.
*

TRS

.MARINE...
157 PM CST

KJB

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO BURNS HARBOR UNTIL
10 PM THURSDAY.

SMALL CRAFT ADVISORY...NEARSHORE BURNS HARBOR TO MICHIGAN CITY IN UNTIL 10 AM SATURDAY.

AREA FORECAST DISCUSSION

NWS TOPEKA KS

347 AM CST THU DEC 8 2011

.DISCUSSION...

TODAY AND TONIGHT...AN UPPER LEVEL TROUGH OVER THE NORTHERN HIGH
PLAINS WILL DIG SOUTHEAST TODAY ACROSS THE CENTRAL PLAINS. THE
STRONGER MID-LEVEL FRONTOGENETICAL FORCING AHEAD OF THE H5 TROUGH WILL
SHIFT SOUTHEAST ACROSS SD INTO EASTERN NE...IA AND NORTHERN MO. A
BAND OF WEAKER MID-LEVEL FRONTOGENETICAL FORCING WILL EXTEND
SOUTHWEST INTO NORTHEAST KS THIS AFTERNOON AND INTO THE EVENING
HOURS BEFORE SHIFTING EAST. THE GFS MODEL FORECAST THE THE
STRONGEST ASCENT AND ENOUGH MOISTURE FOR 1 TO 2 INCHES OF SNOWFALL
ACROSS THE NORTHERN COUNTIES OF THE CWA. THE NAM AND ECMWF ARE NOT
AS AMPLIFIED AND ONLY SHOW ABOUT HALF OF AN INCH TO ONE INCH OF
SNOW ACROSS THE NORTHEAST COUNTIES OF THE CWA. THERE MAY ONLY BE
TRACE AMOUNTS OF SNOWFALL ACROSS THE SOUTHERN COUNTIES OF THE CWA LATE
THIS AFTERNOON AND THIS EVENING. ONCE THE H5 TROUGH AXIS SHIFTS
SOUTHEAST OF THE PLAINS TONIGHT...THE SNOW SHOULD END FROM
NORTHWEST TO SOUTHEAST ACROSS THE CWA DURING THE LATE EVENING
HOURS. A SECOND H5 TROUGH WILL DIG SOUTHWARD ACROSS THE EASTERN
PLAINS THEN MOVE SOUTHEAST ACROSS IA INTO NORTHERN MO DURING THE
EARLY MORNING HOURS OF FRIDAY. ATTM...THE STRONGER FORCING WILL
REMAIN NORTH AND NORTHEAST OF THE CWA...THUS ANY LIGHT SNOW SHOULD
MOVE SOUTHEAST FROM EASTERN NE...SOUTHEAST ACROSS IA INTO NORTHERN
MO THROUGH THE MORNING HOURS OF FRIDAY.

HIGHS TODAY WILL RANGE FROM THE LOWER TO MID 30S ACROSS THE NORTHERN
COUNTIES WHERE CLOUD COVER WILL INCREASE DURING THE MID MORNING
HOURS TO THE THE UPPER 30S TO AROUND 40S ACROSS EAST CENTRAL KS.

FRIDAY...A SURFACE RIDGE OF HIGH PRESSURE WILL BUILD SOUTHWARD
ACROSS EASTERN KS. LOW-LEVEL CAA WILL KEEP HIGHS IN THE LOWER TO MID
30S...EVEN THOUGH SKIES WILL CLEAR DURING THE AFTERNOON HOURS.

SATURDAY THROUGH MONDAY...THE FLOW ALOFT WILL BECOME ZONAL.
SOUTHWEST TO SOUTHERLY SURFACE WINDS WILL ALLOW HIGH TEMPERATURES TO
WARM INTO THE LOWER 40S ON SATURDAY WITH MID TO UPPER 40S SUNDAY AND
MONDAY.

MONDAY NIGHT AND TUESDAY...AN UPPER LEVEL TROUGH WILL DIG SOUTHWARD
ACROSS THE WESTERN CONUS INTO THE DESERT SOUTHWEST. A WEAK H5 TROUGH
WILL MOVE EAST ACROSS THE NORTHERN PLAINS AND WILL CAUSE A WEAK COLD
FRONT TO PUSH SOUTHEAST ACROSS THE CWA. THE LOW-LEVELS OF THE
ATMOSPHERE LOOK TOO DRY FOR MEASURABLE PRECIPITATION TO DEVELOP ALONG OR
BEHIND THE FRONT. HIGHS ON TUESDAY WILL COOL SLIGHTLY INTO THE
UPPER 30S TO LOWER 40S.

TUESDAY NIGHT AND WEDNESDAY...THE GFS AND ECMWF MODEL SOLUTIONS
DIFFER IN THE MOVEMENT OF THE UPPER LOW THAT EJECTS OUT EITHER EAST
OR NORTHEAST INTO THE SOUTHERN AND CENTRAL PLAINS. THE GFS SHOWS THE
UPPER LOW MOVING DUE EAST ACROSS WEST TX INTO SOUTHERN OK. THE
ECMWF...SHOWS MORE OF AN OPEN WAVE LIFTING TO THE NORTHEAST ACROSS
KS AND NE. IF THE GFS WERE TO VERIFY THE CWA WOULD REMAIN DRY BUT
COLDER. IF THE ECMWF WERE TO VERIFY THE RAIN AND PERHAPS A FEW
ISOLATED THUNDERSTORMS WILL DEVELOP AS DEEPER MOISTURE AND WARMER
AIR ADVECT NORTHWARD ACROSS THE STATE TUESDAY NIGHT INTO
WEDNESDAY. ATTM...I WILL KEEP AT LEAST A CHANCE FOR RAIN ACROSS
THE CWA ON WEDNESDAY WITH HIGHS IN THE MID TO UPPER 40S...MAY BE
EVEN LOWER TO MID 50S IF THE ECMWF SOLUTION VERIFIES.

GARGAN

.AVIATION...
THE LATEST RUC AND NAM FORECAST SOUNDINGS DO NOT COOL SFC TEMPS OFF
AS MUCH AS EARLIER RUNS. BECAUSE OF THIS THEY ARE LESS AGGRESSIVE IN
SATURATING THE BOUNDARY LAYER. SINCE CONDITIONS ARE GOOD FOR
RADIATIONAL COOLING AND THE POTENTIAL FOR SOME GROUND FOG EXISTS...
WILL KEEP A MENTION FOR TOP AND MHK WHERE THE KS RIVER COULD PROVIDE
ADDITIONAL BOUNDARY LAYER MOISTURE.

MODELS CONTINUE TO SHOW A WEAK SHORTWAVE MOVING ACROSS THIS
AFTERNOON AND EVENING. FORCING FOR PRECIP IS NOT OVERWHELMING.
HOWEVER IT LOOKS LIKE THERE COULD BE A 3 TO 4 HOUR WINDOW FOR SOME
LIGHT SNOW...ESPECIALLY ACROSS NORTHEAST KS. WITH GOOD CONSENSUS IN
MODEL QPF...HAVE SOME CONFIDENCE IN LIGHT SNOW DEVELOPING WITH
INTENSITY BEING FAIRLY LIGHT AND LITTLE ACCUMULATION. THEREFORE ONLY
TAKE THE TAFS TO MVFR IN SPITE OF THE MET MOS SHOWING IFR CONDITIONS.

WOLTERS

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

303 AM CST THU DEC 8 2011

.DISCUSSION...

DAYS 1-2...

THE MAIN FORECAST FOCUS WILL BE ON THE CHANCE FOR LIGHT PRECIP EARLY
IN THE PERIOD.

WV IMAGERY AND 00Z UPPER AIR ANALYSIS INDICATES AN UPPER LEVEL
SHORTWAVE DIPPING SOUTHEAST OUT OF CANADA INTO THE NORTHERN ROCKIES.
A POOL OF H7 MOISTURE IS ACCOMPANYING THE SHORTWAVE EXTENDING FROM
EASTERN MONTANA EAST AND SOUTHEAST INTO THE NORTHERN PLAINS. A COLD
FRONT IS PUSHING SOUTH ACROSS SOUTH DAKOTA NEARING NORTHERN NEBRASKA.

SHORT RANGE MODELS INDICATE THE UPPER LEVEL SHORTWAVE SWINGING
SOUTHEAST OUT OF THE NORTHERN ROCKIES INTO THE NORTHERN PLAINS
TODAY. IT WILL HELP USHER A COLD FRONT SOUTH INTO WESTERN KANSAS
BY THIS AFTERNOON BRINGING WITH IT MUCH COOLER AIR INTO THE REGION.
VERY LITTLE IN THE WAY OF PRECIP IS EXPECTED WITH A LACK OF MOISTURE
IN THE LOWER LEVELS. HOWEVER, AREAS OF LIGHT FREEZING DRIZZLE
OR SNOW CANNOT BE COMPLETELY RULED OUT THIS AFTERNOON ACROSS
NORTHERN PORTIONS OF THE CWA AS TEMPERATURES COOL DOWN QUITE A
BIT NEARLY SATURATING THE LOWER LEVELS. FLURRIES ARE POSSIBLE THIS
EVENING WITH MODEL SOUNDINGS SHOWING BELOW FREEZING TEMPERATURES
AT ALL LEVELS. OTHERWISE, FAIRLY DRY CONDITIONS ARE EXPECTED INTO
THE WEEKEND AS UPPER LEVEL RIDGING BUILDS INTO THE INTERMOUNTAIN
WEST FRIDAY.

TEMPERATURES WILL BE BELOW NORMAL TODAY AS COLDER AIR BEGINS TO
FILTER SOUTH INTO WESTERN KANSAS BY EARLY THIS AFTERNOON BEHIND A
COLD FRONT MOVING ACROSS THE AREA. ALL MODELS SHOW H85 TEMPERATURES
DROPPING TO NEAR TO JUST BELOW 0C ACROSS MUCH OF THE CWA BY MID
DAY. EXPECT HIGHS ONLY UP INTO THE 30S(F) BY THIS AFTERNOON WITH A
FEW LOWER 40S(F) POSSIBLE IN OUR SOUTHEAST, ESPECIALLY WITH
INCREASING CLOUDS. TEMPERATURES WILL REMAIN FAIRLY COLD FRIDAY AS
SURFACE HIGH PRESSURE DRIFTS EAST ACROSS THE CENTRAL PLAINS
KEEPING THE SAME GENERAL AIR MASS IN PLACE ACROSS WESTERN KANSAS.
SHOULD SEE FAIRLY SIMILAR HIGHS ON FRIDAY EVEN WITH FEWER CLOUDS
EXPECTED.

DAYS 3-7...

SPLIT UPPER LEVEL FLOW CONTINUES INTO THE WEEKEND OVER THE PLAINS. A
STRONG UPPER LEVEL SHORTWAVE TROUGH DIGS INTO THE PACIFIC NORTHWEST
ON SUNDAY. BY MONDAY THE NEW ECMWF HAS A CUTOFF UPPER LOW JUST WEST
OF THE SOUTHERN CALIFORNIA COASTLINE AND THE GFS IS FASTER WITH A
MORE OPEN UPPER LOW OVER SOUTHERN CALIFORNIA. ON TUESDAY A NORTHERN
BRANCH WAVE MOVES ACROSS THE UPPER MIDWEST WITH THE GFS CONTINUES TO
PUSH A CLOSED UPPER LOW INTO NEW MEXICO WHILE THE SLOWER ECMWF AND
GEM HAVE A TROUGH MORE WEST INTO SOUTHERN CALIFORNIA. FOR WEDNESDAY
THE GFS CONTINUES A FASTER AND MORE SOUTHERN TRACK INTO NORTHEASTERN
TEXAS WHILE THE ECMWF HAS A NEGATIVELY TILTED OPEN SHORTWAVE TROUGH
LIFTING NORTHEASTWARD INTO NEBRASKA. THE NEW CANADIAN HAS THE UPPER
LOW ON SATURDAY EVENING JUST INTO SOUTHWEST KANSAS AND IS MORE
NEUTRALLY TILTED.

WHAT THIS MEANS ANY SENSIBLE WEATHER WILL HOLD OFF UNTIL THE UPPER
LEVEL LOW LIFTS OUT INTO THE PLAINS ON WEDNESDAY. LOTS OF MODEL
DIFFERENCES WILL MAKE THIS FORECAST INTO THE MIDDLE OF NEXT WEEK A
VERY LOW CONFIDENCE FORECAST WITH THE TRACK OF THE UPPER LOW. THE
ECMWF AND GFS HAVE RAIN AND THE CANADIAN HAS RAIN OR SNOW. FOR NOW
WILL HOLD ONTO CONSENSUS MODEL THAT HAS MOSTLY RAIN AND WARMER TEMPS.

IN GENERAL A LEE LOW WILL BRING WARMER SOUTH TO SOUTHWEST SURFACE
WINDS INTO THE WEEKEND WITH HIGHS INTO THE 40S. CANADIAN HIGH
PRESSURE MOVES INTO THE PLAINS ON MONDAY AND TUESDAY WITH SLIGHTLY
COOLER HIGH TEMPERATURES. THEN FOR WEDNESDAY THE ECMWF HAS THE UPPER
LOW MUCH MORE NORTH AND BRINGS IN HIGHER DEWPOINTS AND QPF TO
WESTERN KANSAS. FOR NOW WILL CONTINUE WITH CONSENSUS POPS AND TEMPS
WHICH FAVOR HIGHEST POPS SOUTH AND EAST FA AND HIGHS IN THE 50S.

OVERNIGHT LOWS LOOK TO BE IN THE 20S WEST AND NORTHWEST FA TO THE
30S IN THE SOUTH AND SOUTHEAST.

.AVIATION...

FOR THE 06Z TAF ISSUANCE...

THIS EVENING`S KDDC UPPER AIR SOUNDING CONTINUES TO SHOW DEEP DRY
LOWER AND MIDDLE TROPOSPHERIC LAYERS WITH DEEP NORTHWEST FLOW ALOFT.
THE LATEST RAPID REFRESH RUC MODEL IS DELAYING THE DEVELOPMENT OF
MVFR STRATUS CONSIDERABLY LATER INTO THE LATE AFTERNOON ACROSS
NORTHWEST KANSAS. CONSIDERING THE CURRENT LACK OF LOW CLOUD
DEVELOPMENT ACROSS THE NORTHERN HIGH PLAINS REGION, WE CAN`T FIND A
GOOD REASON TO DISCOUNT THIS MODEL SHIFT AND HAVE DELAYED MVFR
CEILINGS BY ABOUT 8 HOURS IN THE TAF TIME FRAME.

.PRELIMINARY POINT TEMPS/POPS...
DDC 37 17 37 17 / 10 10 0 0
GCK 33 15 33 15 / 10 10 0 0
EHA 35 17 32 20 / 10 10 0 0
LBL 37 18 37 18 / 10 10 0 0
HYS 32 15 30 15 / 40 20 0 0
P28 42 20 38 18 / 10 10 0 0

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

FN32/06/06

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

1148 PM CST WED DEC 7 2011

.UPDATE...

.PREV DISCUSSION... /ISSUED 546 PM CST WED DEC 7 2011/

UPDATE...

AVIATION /FOR THE 06Z TAF ISSUANCE/

PREV DISCUSSION... /ISSUED 341 PM CST WED DEC 7 2011/

SYNOPSIS...

ON THE SYNOPTIC SCALE TODAY...AN UPPER LOW WAS CENTERED OVER THE
SOUTHERN APPALACHIANS WITH WIDESPREAD PRECIPITATION OVER MUCH OF THE
MID ATLANTIC AND INTERIOR NORTHEAST CONUS. SHORTWAVE RIDGING WAS
INFLUENCING SENSIBLE WEATHER OVER THE CENTRAL CONUS WITH DOWNSLOPE
WARMING OCCURRING OVER THE CENTRAL PLAINS. AFTERNOON TEMPERATURES
ROSE TO THE MID AND UPPER 40S OVER SOUTHWEST KANSAS IN THE DOWNSLOPE
NORTHWEST WINDS. ANOTHER SHORTWAVE TROUGH WAS LOCATED OVER THE
ALBERTA ROCKIES AND CONTINUED TO MOVE SOUTHEAST AROUND THE SOUTHEAST
SIDE OF A LARGE LONGWAVE CYCLONE THAT WAS CENTERED OVER WESTERN
HUDSON BAY. -UMSCHEID

DISCUSSION...

DAYS 1-2...

THE SHORTWAVE TROUGH OVER SOUTHERN ALBERTA WILL REACH WYOMING BY 12Z
THURSDAY...AND A BAND OF MID LEVEL FRONTOGENESIS AND ENHANCED RH
WILL DEVELOP AHEAD OF THE DISTURBANCE OVER WESTERN NEBRASKA. THIS
WILL SHIFT SOUTHEAST THROUGH THE DAY THURSDAY ACROSS SOUTHERN
NEBRASKA/NORTHERN KANSAS. IN THE LOWER TROPOSPHERE (900 TO
800MB)...LOW LEVEL RH WILL INCREASE TO THE POINT THAT LOW STRATUS
WILL FORM BY LATE MORNING BEHIND THE DEVELOPING SURFACE COLD FRONT.
A FETCH OF NORTHEAST WINDS IN THIS LAYER WILL DEVELOP WHICH WILL
HAVE UPSLOPE COMPONENT FROM SOUTHEAST NEBRASKA/NORTHEAST KANSAS TO
SOUTHWEST KANSAS. A WEAK CYCLONIC CIRCULATION WILL DEVELOP OVER
NORTHWEST OKLAHOMA AROUND 850MB...WHICH WILL YIELD SOME WEAK
FRONTOGENESIS ACROSS THE SOUTHERN DDC FA BY LATE IN THE DAY/EARLY
EVENING THURSDAY. THE SATURATION OF THE 900-800MB LAYER WILL STILL
BE PRETTY FAR NORTH OF THE BEST FRONTOGENESIS IN THIS LAYER...SO
THIS DISCONNECT BETWEEN THE SATURATION AND LIFT WILL LIMIT
WIDESPREAD DRIZZLE FORMATION. NEVERTHELESS...THE UPSLOPE ALONE ON
THE NORTHEAST WINDS MAY BE ENOUGH TO GENERATE AT LEAST PATCHY
FREEZING DRIZZLE.

THE DEPTH OF THE SATURATED LAYER DURING THE DAY AND EARLY EVENING
TOMORROW IS EXPECTED EXTEND UP TO ABOUT 800 OR 750MB...WHERE
TEMPERATURES WILL BE -4 OR -5C...SO THE PRECIPITATION TYPE SHOULD BE
FREEZING DRIZZLE INSTEAD OF SNOW FLURRIES. A DEEPER MOIST LAYER IS
EXPECTED FARTHER NORTH LATE IN THE DAY (SAY NORTH OF HIGHWAY
4)...AND THE PROBABILITY OF SNOW FLURRIES IS GREATER...SO WILL CARRY
FREEZING DRIZZLE OR SNOW FLURRIES UP THERE LATE IN THE DAY/EARLY
EVENING. THE EVENT...SHOULD IT EVEN UNFOLD...WILL END BY LATE
EVENING/MIDNIGHT TIME FRAME AS THE SHORTWAVE TROUGH RESPONSIBLE
QUICKLY EXITS THE CENTRAL PLAINS.

THE REMAINDER OF THE FORECAST WILL BE DRY THROUGH FRIDAY AS
SUBSIDENCE PREVAILS AND SKIES CLEAR. VERY COLD AIR IS NOT EXPECTED
AFTER THIS WAVE MOVES BY AS MID LEVEL DOWNSLOPE WILL DEVELOP ONCE
AGAIN IN THE 850-700MB LAYER...WHICH WILL SUPPORT SURFACE HIGHS IN
THE UPPER 30S TO LOWER 40S. -UMSCHEID

DAYS 3-7...

THE EXTENDED PERIOD BEGINS 00Z SATURDAY. HAVE STUCK WITH THE
INITIALIZED CR ALLBLEND GRIDS AS THIS WAS THE CONSENSUS ESTABLISHED
WITH SURROUNDING WFOS. THERE IS A BIT OF UNCERTAINTY NEXT WEDNESDAY
REGARDING POPS. THIS IS VERY FAR IN THE EXTENDED PERIOD AND IS A LOW
CONFIDENCE FORECAST AS THERE ARE SIGNIFICANT DIFFERENCES BETWEEN THE
12Z GFS AND 12Z ECMWF IN ADDITION BETWEEN THE 00Z ECMWF AND 12Z
ECMWF.

SATURDAY/SUNDAY:
KANSAS WILL BE IN SPLIT FLOW NEXT WEEKEND. INCREASING WESTERLY FLOW
IN ASSOCIATION WITH THE SOUTHERN BRANCH JET WILL RESULT IN SURFACE
LEE TROUGHING ACROSS EASTERN COLORADO. 850 HPA TEMPERATURES ARE
FORECAST IN THE 2 TO 3 DEG C RANGE WHICH SUPPORT TEMPERATURES IN THE
40S DEG F ACROSS THE REGION...WHICH IS NEAR CLIMATOLOGY. THE
FORECAST WILL REMAIN DRY WITH BREEZY SOUTHERLY TO SOUTHWESTERLY
WINDS. LOWS WILL BE NEAR NORMAL TOO...PARTICULARLY SUNDAY WITH 20S
DEG F PREVAILING FOR SW KANSAS.

MONDAY:
AN UPPER LEVEL SHORTWAVE TROUGH IN ASSOCIATION WITH THE NORTHERN
BRANCH JET WILL USHER IN A COLD FRONT MONDAY. THIS FRONT DOESN`T
LOOK VERY STRONG AND IS EXPECTED TO BE DRY. TEMPERATURES WILL COOL
DOWN ABOUT 5 OR SO DEGREES MONDAY. ANOTHER IMPACT FROM THE FRONT
WILL BE INCREASING CLOUD COVER, MAINLY IN THE FORM OF MID TO HIGH
LEVEL CLOUDS.

TUESDAY:
WE WILL BE IN BETWEEN WEATHER SYSTEMS. THE SOUTHERN BRANCH JET
WILL INTENSIFY RESULTING IN THE FORMATION OF A WEAK LEE SURFACE
TROUGH AND SLIGHT WARMER TEMPERATURES (WARM AIR ADVECTION PATTERN).
WE COULD SEE SOME HIGH LEVEL CLOUDS CONTINUING TUESDAY AS WELL AS
MID TO UPPER LEVEL FLOW INCREASES FROM THE SOUTHWEST IN ASSOCIATION
WITH THE APPROACHING SHORTWAVE TROUGH/JET. -SUGDEN

WEDNESDAY:
THERE ARE LARGE DIFFERENCES BETWEEN THE GFS AND ECMWF AT THIS POINT.
THEY BOTH SHOW AN UPPER LEVEL SYSTEM MOVING ACROSS THE REGION WITH
RETURN FLOW SETTING UP AND HIGHER DEWPOINTS ADVECTING IN FROM THE
GULF OF MEXICO (30S TO 40S DEG F). AS MENTIONED ABOVE, LEFT POPS
ALONE FOR THIS PERIOD DUE TO THE TIMING DIFFERENCES. THE 12Z ECMWF
IS ALSO DRIER THAN THE 00Z ECMWF WHICH FURTHER COMPLICATES THE
WEATHER SCENE IN ABOUT A WEEK FROM NOW. -SUGDEN

.PRELIMINARY POINT TEMPS/POPS...
DDC 16 37 18 39 / 0 10 10 0
GCK 14 32 17 36 / 0 10 10 0
EHA 15 34 18 35 / 0 10 10 0
LBL 16 39 19 39 / 0 10 10 0
HYS 14 31 15 33 / 10 10 10 0
P28 18 43 21 41 / 0 10 10 0

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

FN99/99

AREA FORECAST DISCUSSION

NWS TOPEKA KS

1118 PM CST WED DEC 7 2011

...AVIATION UPDATE...

.DISCUSSION...
SEE PREV DISCUSSION.

WOLTERS

.PREV DISCUSSION... /248 PM CST WED DEC 7 2011/
WEAK MID-LEVEL DISTURBANCE COMBINED WITH MID-LEVEL ISENTROPIC LIFT
HAS LED TO AN AC DECK ACROSS EASTERN NEBRASKA...FAR NORTHEAST KS
AND AREAS EAST THIS AFTERNOON. THIS SHOULD MOVE OFF TONIGHT WITH
SOME CLEARING EXPECTED. WEAK PRESSURE GRADIENT TONIGHT COMBINING
WITH MOSTLY CLEAR SKIES COULD LEAD TO SOME LIGHT FOG IN PLACES
NEAR SUNRISE. WOULD NOT EXPECT IT TO BE DENSE OR WIDESPREAD AND
HAVE NOT MENTIONED IT IN THE GRIDS/FORECAST.

ON THURSDAY...A LITTLE MORE DEFINED UPPER TROUGH SWINGS
SOUTHEASTWARD OUT OF NEBRASKA WITH ASSOCIATED MID AND UPPER LEVEL
FORCING. ATMOSPHERE QUITE STABLE AND MOISTURE LACKING...SO WHILE
SATURATION WILL OCCUR AND SNOW WILL RESULT...DO NOT EXPECT ANY
SIGNIFICANT ACCUMULATION. AFTERNOON CHANCES SHOULD REMAIN NORTH
OF I70. GDP

THURSDAY NIGHT THROUGH SATURDAY...WEAK FRONTOGENESIS CONTINUES
THROUGH AT LEAST THE EARLY EVENING HOURS ON THURSDAY AS THE TROF
NEARS. LOW TO MID LEVELS SHOULD BE SATURATED ENOUGH FOR LIGHT SNOW
TO SWING EAST THROUGH MAINLY NORTHERN AND CENTRAL LOCATIONS. MAY
SEE THE SNOW LAST LONG ENOUGH FOR VERY LOW ACCUMULATIONS TO
RESULT...WITH THIS FAST-MOVING SYSTEM EXITING BY DAWN. NAM AND GFS
ARE QUITE SIMILAR WITH ANOTHER AREA OF LIGHT SNOW DEVELOPING IN
CENTRAL NEBRASKA LATE IN THE NIGHT...APPARENTLY TIED TO ANOTHER
AREA OF WEAK FRONTOGENESIS AROUND 850MB AS THE UPPER TROF PASSES.
WITH QUESTIONS ON THE POSITIONING OF THIS FEATURE AND THE LIKELY
LIMITED IMPACT OF THIS SHALLOW AND TRANSIENT FORCING...WILL NOT
MENTION ANY PRECIP/FLURRIES AT THIS POINT. SKIES SHOULD SLOWLY
CLEAR FRIDAY AND MAY SET THE STAGE FOR A RATHER COOL FRIDAY NIGHT
IF SNOWPACK AND WEAK WIND FIELDS CAN ALIGN A BIT BETTER THAN
EXPECTED CURRENTLY. WARM AIR ADVECTION ENSUES BY LATE IN THE NIGHT
FOR A MUCH WARMER SATURDAY ON SOUTHWEST WINDS. KP

SATURDAY NIGHT THROUGH WEDNESDAY...ON SUNDAY WEAK WARM AIR ADVECTION
WILL CONTINUE ACROSS THE CENTRAL U.S. WITH WEAK UPPER LEVEL RIDGING
IN PLACE. SOUTHERLY FLOW WILL CONTINUE ACROSS THE REGION WITH HIGH
PRESSURE OVER THE OHIO RIVER VALLEY AND LEE CYCLOGENESIS TAKING
PLACE. WITH PLENTY OF INSOLATION TEMPERATURES WILL WARM INTO THE LOW
AND MID 40S ON SUNDAY. LATE MONDAY INTO TUESDAY MORNING A TROUGH
WILL MOVE ACROSS THE NORTHERN PLAINS. THIS TROUGH WILL PUSH A WEAK
COLD FRONT THROUGH THE CWA LATE MONDAY INTO TUESDAY MORNING. COLD
AIR ADVECTION WILL BE SHORT-LIVED WITH BOTH THE GFS AND ECMWF
INDICATING AN UPPER LEVEL TROUGH THAT WILL EJECT OUT OF THE DESERT
SOUTHWEST INTO THE CENTRAL PLAINS LATE TUESDAY INTO WEDNESDAY.
MODELS INDICATE THAT MOISTURE RETURN AND LIFT AHEAD OF THIS SYSTEM
WILL BE SUFFICIENT FOR PRECIPITATION ACROSS THE CWA LATE TUESDAY
NIGHT AND CONTINUING INTO THE DAY ON WEDNESDAY. AT THIS TIME...THE
DOMINANT PRECIPITATION TYPE SHOULD BE RAIN WITH TEMPERATURES WARMING
OVERNIGHT TUESDAY WITH 850 MB TEMPERATURES APPROACHING 6-10 DEGREES
CELSIUS TUESDAY NIGHT. A WARM FRONT IS EXPECTED TO RACE NORTH OF THE
CWA DURING THE DAY ON WEDNESDAY WITH HIGHS PUSHING INTO THE UPPER
40S AND LOWER 50S ACROSS THE CWA. MEA

.TOP WATCHES/WARNINGS/ADVISORIES...NONE.

AREA FORECAST DISCUSSION

NWS LOUISVILLE KY

1211 AM EST THU DEC 08 2011

...Updated Aviation Discussion...

...Forecast Update...

Did a minor update to account for current temperature and sky
trends. The remaining forecast is on track. Updated products have
been issued.

Dry air continues to migrate into the forecast area. Current
T/Td spreads of generally 6-9 degrees yields relative humidity
values in the 70 to low 80 percent range. Latest guidance,
particularly LAMP data, handle the current conditions well and keep
a 4-5 degree spread through the morning hours. With this T/Td spread
and westerly wind speeds in the 3-5 mph range overnight, believe it
will be difficult for fog formation. Additionally, the gusty
northwest winds this afternoon across much of the forecast area
actually aided in drying the surface a bit. At this time, the only
potential location for fog formation would be confined to the water
surfaces of rivers and lakes in the form of steam fog (also known as
evaporation fog), as this cold airmass works over slightly warmer
river/lake waters. Once again, this would be localized to very near
the water surface, if fog were to form.

.Short Term (Tonight and Thursday)...

First off, snow band was not as impressive as the HRRR earlier today
made it out to be. County officials in our Lake Cumberland region
have all indicated very little snow stuck. Webcams from that area
also look mostly just wet and not white. Had some pictures with snow
from the LEX-area webcams in a brief band that went through their in
the last couple of hours, but likewise nothing has accumulated.
Surface temperatures are just too warm, in the mid 30s along with
the still wet grounds from the rain earlier in the week.

Sunshine is poking out some in cloud cover west of a KLEX to
Scottsville line. With any heating though, additional low clouds are
developing. These clouds may yet produce some scattered very light
flurries across central KY, but temperatures will not be cool enough
where these clouds are to promote lots of snow. With the cloud
cover, temperatures are holding to around 40 degrees at most.

Skies should clear out overnight as deep dry air moves into the
region. High pressure will move in south of the region, so expect a
general westerly wind through the night. Expect temperatures to fall
into the 20s areawide overnight under these clear skies. Sheltered
locations may see the low 20s.

High pressure will be centered over the Appalachians during the day
Thursday. Thus expect a southwesterly flow. Clear skies should allow
us to reach the low/mid 40s areawide, roughly 5 degrees below normal.

.Long term (Thursday night - Wednesday)...

A digging shortwave will dive from the northern plains into the
lower Great Lakes on Friday. Moisture return ahead of this system
will be limited and therefore continued to only mention flurries in
the forecast early Friday morning across southern Indiana, gradually
working eastward across north central Kentucky and the Bluegrass
through the day. Temperatures ahead of the front will likely warm
enough for just sprinkles in the late morning and afternoon. In the
morning and the evening, moisture to about 700 mb should yield
some potential for ice crystals as temps at this level will be
around -10 C. No impacts from these flurries are anticipated.

Otherwise, cold frontal boundary moves through Friday afternoon and
evening with a cold airmass lurking for the weekend. Lows Friday
night are expected to drop into the lower 20 in most spots, with a
few upper teens possible across southern Indiana and perhaps the
Bluegrass. High temperatures on Saturday will struggle, only making
it to the low and mid 30s. Saturday night will bring more
temperatures right around the 20 degree mark.

Sunday into the middle of next week, mid level flow will gradually
transition from a progressive zonal flow then try to head back toward
the classic La Nina pattern we have been seeing which would yield
southwest flow aloft with a ridge to our southeast and a developing
trough over the western CONUS. Will keep forecast through Wednesday
dry, although some signs point to another potent system tracking
into the region possibly Thursday or Friday. Although this is pretty
far out, confidence in the recent pattern supported by
teleconnections could lead to another substantial precipitation
event across the Ohio Valley. Stay tuned.

Highs through the first half of next week will gradually moderate
toward the mid 40s, with upper 40s and low 50s ahead of the next
system possible on Wednesday. Lows each night will be in the 20s,
warming to the low 30s by Wednesday morning.

.Aviation (06Z TAF Issuance)...

Latest satellite imagery reveals clear skies at the terminals this
evening. VFR conditions are expected through the TAF period as high
pressure builds in from the west. Dry air continues to push into
the region and T/Td spreads are still forecast to be large enough to
limit fog formation overnight. In fact, a look at all of the
available 08/00Z guidance shows very little if any fog development
overnight as the surface winds stay up around 2-4 knots. Winds
should slacken late tonight and then resume after sunrise out of the
southwest as high pressure moves into the Appalachian mountains.

.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$

Update...........MJP
Short Term.......RJS
Long Term........BJS
Aviation.........MJ

AREA FORECAST DISCUSSION

NWS WAKEFIELD VA

1007 PM EST FRI DEC 9 2011

.SYNOPSIS...
A COLD FRONT MOVES ACROSS THE AREA LATE TONIGHT...THEN OFF THE
COAST SATURDAY MORNING. HIGH PRESSURE BUILDS IN FROM THE WEST
SATURDAY AFTERNOON...THEN SETTLES ACROSS THE AREA SATURDAY NIGHT
AND SUNDAY. A TROUGH OF LOW PRESSURE WILL DEVELOP OFF THE SOUTHEAST
COAST MONDAY AND TUESDAY. HE HIGH SLOWLY MOVES OFF TO THE
NORTHEAST.

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
FIRST WAVE OF SHWRS NOW MOVG NE ALONG ERN SHORE AREAS. SECOND WAVE
OF SHWRS MOVG NE FROM ERN NC AND BOTH RUC AND WRF MODELS HAVE THESE
MOVG NE ALONG VA / MD CSTL SCTNS THRU THE OVERNIGHT HRS. ALL THIS
AHEAD OF STRNG CDFRNT PROGGED TO PUSH THE LOW OFFSHORE SAT MORNING.
UPDATE WAS TO BUMP UP CLOUD COVERAGE TO M CLDY W AND CLDY E. KEPT
CHC POPS ALONG CSTL COUNTYS WITH A BUFFER ZONE OF SLGHT CHC POPS W
OF CHES BAY GIVEN CRNT RADAR TRENDS AND MODEL TRENDS.

UPR JET STRENGTHENS LATE TONITE AS THE MID/UPPER LEVEL FLOW AMPLIFIES
ACRS THE GREAT LAKES. THIS HELPS LOW PRESSURE DEEPEN OFF THE COAST
EARLY SAT...AND MAY SEE SOME LINGERING SHOWERS INTO SAT MORNING (MAINLY
ALONG THE COAST). DEEP MSTR WILL NOT BE PRESENT ABOVE -10C...SO QPF
AMOUNTS OF A FEW HUNDREDS PSBL. LOWS STAY ABOVE FREEZING...MAINLY IN
THE M30S-M40S. XCPTN BEING FROM ARND LKU-FVX WHERE IT MAY DROP TO 32
BY SUNRISE.

.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
HAVE SLOWED DOWN THE CLEARING SKY A BIT ON SAT AS LOW LEVEL FLOW
IS MORE N RATHER THAN NW. OVERALL...EXPECT MOSTLY CLOUDY SKIES IN
THE EAST IN THE MORNING...BECOMING PARTLY SUNNY IN THE AFTN
(CLEARING EARLIER ALONG/W OF I-95). HIGHS MAINLY IN THE UPPER 40S
TO LOWER 50S.

SAT NIGHT-MON...MODELS IN GOOD AGREEMENT WITH STRONG MODIFIED
ARCTIC (1035-1040 MB) SFC HIGH PRESSURE BECOMING CENTERED FROM THE
OHIO VALLEY INTO THE MID ATLC STATES SAT NIGHT THROUGH SUNDAY.
THIS WILL BRING A COLD AND VERY DRY AIRMASS INTO THE REGION...LOWS
SAT NIGHT INTO THE 20S OVER MOST AREAS..30S ALONG THE COAST. SUNNY
AND COLD SUNDAY WITH HIGHS IN THE 40S ALL AREAS. AS HIGH RETREATS
NE ON MON...COULD SEE SOME INCREASING CLOUDS/MSTR W/ SFC TROUGH
DEVELOPING OFF THE SE COAST. FOR NOW...KEEPING IT PARTLY SUNNY AND
CONTINUED COOL WITH HIGHS IN THE 40S TO LWR 50S.

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
THE EXTENDED PERIOD BEGINS MONDAY NIGHT AND TUESDAY WITH MID-LEVEL
RIDGING OVER THE GULF COAST AND SOUTHEAST...WITH SURFACE HIGH
PRESSURE ANCHORED OVER THE MID ATLANTIC REGION. THIS SHOULD PRODUCE
DRY CONDITIONS AND SEASONAL TEMPERATURES ACROSS THE LOCAL AREA. A
WEAK DRY COLD FRONT IS EXPECTED TO PASS ACROSS THE AREA TUESDAY
NIGHT FOLLOWED BY A RETURN OF HIGH PRESSURE WEDNESDAY. ANY
TEMPERATURE CHANGE BEHIND THIS FRONT APPEARS MINIMAL AT THIS POINT.
A WARMING TREND IS EXPECTED TOWARD THE END OF NEXT WEEK AHEAD OF A
COLD FRONT THAT SLOWLY SAGS TOWARD THE AREA FROM THE NORTHWEST. THE
CHANCE OF RAIN WITH THIS FRONT APPEARS VERY LOW AT THIS TIME.

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
CLOUDS CONTINUE TO STREAM OVER THE MID ATLANTIC REGION FROM THE
GULF AND ATLANTIC OCEAN. A SURFACE TROF OVER EASTERN VA AND
NC...ALONG WITH A WEAK LOW OFF THE NC COAST...ARE HELPING TO
PRODUCE MVFR STRATUS AND STRATOCU CLOUDS ALONG THE COASTAL AREAS
UP THRU THE EASTERN SHORE. CEILINGS ARE MOSTLY VFR OVER INTERIOR
SECTIONS BUT THERE ARE SOME PATCHY AREAS OF MVFR CONDITIONS.
ANOTHER SURFACE OVER WESTERN VA WILL MOVE THRU THE REGION TONIGHT
AND WILL BE FOLLOWED BY A COLD FRONT THAT WILL PASS OFF THE COAST
BY SUNRISE SAT MORNING. HIGH PRESSURE AND VFR CONDITIONS WILL
BUILD IN BEHIND THE FRONT BUT SOME MID AND HIGH CLOUDS COULD
LINGER THRU THE DAY BEFORE SKIES CLEAR AT NIGHT. ALSO EXPECT SOME
GUSTY NW-NE 15-20 KT WINDS BEHIND THE FRONT THAT WILL PERSIST INTO
THE EVENING.

HIGH PRESSURE AND VFR WX EXPECTED FOR SUN AND MON.

.MARINE...
A WEAK AREA OF LOW PRESSURE MOVES UP THE COAST TONIGHT AHEAD OF A
COLD FRONT APPROACHING FROM THE NORTHWEST. THE COLD FRONT CROSSES
THE COAST LATE TONIGHT FOLLOWED BY A STEADY CAA SURGE SLOWLY
TAPERING OFF N-S LATE SATURDAY INTO EARLY SUNDAY...WITH SEAS
REMAINING AROUND 5 FT INTO SUNDAY AFTERNOON. INHERITED (LOW-END
CRITERIA) SCA FLAGS FOR THIS SURGE REMAIN ON TRACK. SURFACE HIGH
PRESSURE STEADILY BUILDS ACROSS THE NORTHERN MID ATLANTIC THROUGH
EARLY NEXT WEEK AS LOW PRESSURE LINGERS OVER THE SUBTROPICAL WESTERN
ATLANTIC. THIS WILL MAINTAIN NNE FLOW ACROSS THE LOCAL AREA WITH THE
STRONGEST SPEEDS (AROUND 15 KT) S. SEAS WERE CAPPED AROUND 4 FT AT
THIS POINT...BUT THE FLOW PATTERN COULD KEEP SEAS AROUND 5 FT OFF
THE NC OUTER BANKS.

.HYDROLOGY...
FLOOD WARNINGS REMAIN IN EFFECT FOR JAMES RIVER AT WESTHAM (MODERATE
FLOODING) AND AT RICHMOND CITY LOCKS 9MINOR FLOODING). SEE FLSAKQ
FOR DETAILS.

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM SATURDAY TO 4 PM EST SUNDAY FOR
ANZ634.
SMALL CRAFT ADVISORY FROM 6 AM SATURDAY TO 1 PM EST SUNDAY FOR
ANZ631-632.
SMALL CRAFT ADVISORY FROM 6 AM SATURDAY TO 6 PM EST SUNDAY FOR
ANZ633-650-652-654.
SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EST SATURDAY FOR ANZ630.
SMALL CRAFT ADVISORY FROM 9 AM SATURDAY TO 6 PM EST SUNDAY FOR
ANZ656-658.

$$
SYNOPSIS...LKB
NEAR TERM...MPR
SHORT TERM...LKB
LONG TERM...AJZ
AVIATION...JEF
MARINE...AJZ/JEF
HYDROLOGY...AKQ

AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

703 PM EST FRI DEC 9 2011

.SYNOPSIS...
AFTER SOME SNOW SHOWERS TONIGHT WITH A COLD FRONT...EXPECT DRY AND
COLD WEATHER FOR THE WEEKEND. THE NEXT CHANCE FOR PRECIPITATION
WILL NOT COME UNTIL TUESDAY NIGHT.

.NEAR TERM /THROUGH SATURDAY/...
SOME ADJUSTMENTS TO BE MADE AS FORWARD PROGRESSION OF THINNING
LINE OF SNOW SHOWERS HAS SLOWED COMPARED TO GRID TIMING. STILL KEPT
THE LIKELY CHANCE POPS EARLY AND THEN BACKED OFF AS MOISTURE IS
REALLY BEING SQUEEZED OUT OF THE FRONT. THIS HAS BEEN INDICATED ON
THE LATEST HI-RES MODEL RUNS. STILL...SHORTWAVE SHOULD ALLOW FOR
THE PRODUCTION OF SNOW...ALBEIT BRIEF AND MINIMAL IN MOST
LOCATIONS. BEYOND SLIGHT POP ADJUSTMENTS...MADE CHANGES TO TEMPS
AND DEWPOINTS FOR THE OVERNIGHT PERIOD BASED OFF OF THE MOST
RECENT OBSERVATIONS AND TRENDS. HRRR/NAM HAD THE MOST ACCURATELY
DEPICTED TEMPS/DEWPTS SO WENT WITH THOSE VALUES.

PREVIOUS DISCUSSION FOLLOWS...
LINE OF LIGHT RADAR RETURNS FROM SNOW SHOWERS CAN BE SEEN MOVING
STEADILY TO THE EAST ACROSS WESTERN OHIO AND EASTERN INDIANA. MODEL
STILL DO NOT SHOW MUCH DEEP MOISTURE WITH THE SYSTEM. HOWEVER...4KM
HI-RES WRF NMM AND HRRR RUNS HAVE BEEN CONSISTENT SHOWING A 3-6 HOUR
WINDOW OF SNOW SHOWERS MOVING THROUGH DURING THE EVENING. HAVE
INCREASED POPS TO LIKELY DURING THE EVENING HOURS NORTHWEST OF THE
RIDGES...ALTHOUGH FEEL PRETTY CONFIDENT THAT ACCUMULATION WILL
REMAIN LESS THAN HALF AN INCH. AS ALWAYS...RIDGES AND LOCATIONS OF
I-80 WILL RECEIVE SLIGHTLY MORE ACCUMULATION. THINK THAT MOST
SNOWFALL SHOULD BE OUT OF THE REGION BY SUNRISE SATURDAY...WITH
ISOLATED SNOW SHOWERS REMAINING ACROSS THE RIDGES AS THE COLD FRONT
COMPLETES ITS PASSAGE ACROSS THE REGION. COLD AIR BEHIND THE FRONT
WILL RESULT IN THE COLDEST HIGH TEMPERATURES SO FAR THIS
SEASON...WITH MOST LOCATIONS REMAINING BELOW FREEZING ALL DAY.

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
WEATHER WILL BE VERY QUIET DURING THIS PORTION OF THE FORECAST. HIGH
PRESSURE WILL REMAIN IN CONTROL OVER THE EAST COAST...AND
SOUTHWESTERLY WINDS WILL PREVENT ANY LAKE EFFECT OR UPSLOPE SHOWERS
FROM OCCURRING. OVERNIGHT LOWS WILL BE THE COLDEST OF THE
SEASON...WITH ALL LOCATIONS DROPPING IN THE TEENS. IF ENOUGH
RADIATIONAL COOLING OCCURS ALONG THE SNOWPACK IN THE RIDGES...TEMPS
HERE COULD REACH THE SINGLE DIGITS. TEMPERATURES WILL MODERATE
DURING THE PERIOD...WITH A RETURN TO NORMAL HIGHS BY MONDAY.

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
PER HPC GUIDANCE, FAVORED RECENT ECMWF MODEL OUTPUT WITH SOME NAEFS
INFLUENCE. THESE MODEL SOLUTIONS MAINTAINED THE IDEA THAT THE UPPER
LEVEL JETSTREAM ACROSS THE U.S. WILL BECOME MORE ZONAL DURING THE
COMING WEEK. HENCE TEMPERATURES SHOULD BE NEAR SEASONABLE LEVELS
THIS PERIOD, WHICH IS ALSO SUPPORTED BY GFS MOS.

HIGH PRESSURE WILL PROVIDE DRY CONDITIONS INTO TUESDAY. A COLD
FRONTAL PASSAGE MAY PROVIDE SOME SNOW AND RAIN SHOWERS TUESDAY
NIGHT AND WEDNESDAY. A BETTER DEVELOPED LOW PRESSURE SYSTEM MAY
PROVIDE A SECOND BOUT OF SNOW AND RAIN SHOWERS THURSDAY INTO
POSSIBLY EARLY FRIDAY. NAEFS MODEL OUTPUT SUGGESTS SOME INJECTION
OF NORTHWEST FLOW ENERGY NEXT WEEKEND WHICH WOULD RESULT IN COLDER
TEMPERATURES NEXT WEEKEND.

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
GENERAL VFR CONDITIONS THIS EVENING AHEAD OF A WEAK COLD FRONT.
A NARROW BAND OF SNOW SHOWERS WITH THE FRONT WILL RESULT IN
FLIGHT CONDITIONS DETERIORATING TO MAINLY MVFR WITH SNOW SHOWERS
WITH THE FRONTAL PASSAGE. THE SNOW SHOWERS WILL LAST FOR ABOUT
THREE HOURS BEFORE ENDING. . BRIEF IFR CONDITIONS ARE POSSIBLE WITH
THE SNOW SHOWERS, PARTICULARLY NORTH, WITHIN THE I-80 CORRIDOR, AT
TAF SITES SUCH AS KFKL AND KDUJ.

BY 06Z FOR TAF SITES SOUTH OF THE I-80 CORRIDOR, SNOW SHOWERS WILL
DISSIPATE, AND LINGERING STRATOCUMULUS CEILINGS WILL LIFT TO VFR
LEVELS. WITHIN THE I-80 CORRIDOR, COLD WESTERLY WINDS CAN INDUCE
SOME LAKE EFFECT SNOW SHOWERS WHICH CAN CAUSE MVFR STRATOCUMULUS
AND BANDS OF SCATTERED IFR SNOW SHOWERS TO LINGER INTO DAYBREAK
SATURDAY.

OUTLOOK...SATURDAY NIGHT THROUGH WEDNESDAY...
VFR INTO TUESDAY. COLD FRONTAL SHOWERS OF SNOW AND RAIN CAN CAUSE
RESTRICTIONS TUESDAY NIGHT INTO WEDNESDAY.

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

AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

635 PM EST FRI DEC 9 2011

.SYNOPSIS...
AFTER SOME SNOW SHOWERS TONIGHT WITH A COLD FRONT...EXPECT DRY AND
COLD WEATHER FOR THE WEEKEND. THE NEXT CHANCE FOR PRECIPITATION
WILL NOT COME UNTIL TUESDAY NIGHT.

.NEAR TERM /THROUGH SATURDAY/...
LINE OF LIGHT RADAR RETURNS FROM SNOW SHOWERS CAN BE SEEN MOVING
STEADILY TO THE EAST ACROSS WESTERN OHIO AND EASTERN INDIANA. MODEL
STILL DO NOT SHOW MUCH DEEP MOISTURE WITH THE SYSTEM. HOWEVER...4KM
HI-RES WRF NMM AND HRRR RUNS HAVE BEEN CONSISTENT SHOWING A 3-6 HOUR
WINDOW OF SNOW SHOWERS MOVING THROUGH DURING THE EVENING. HAVE
INCREASED POPS TO LIKELY DURING THE EVENING HOURS NORTHWEST OF THE
RIDGES...ALTHOUGH FEEL PRETTY CONFIDENT THAT ACCUMULATION WILL
REMAIN LESS THAN HALF AN INCH. AS ALWAYS...RIDGES AND LOCATIONS OF
I-80 WILL RECEIVE SLIGHTLY MORE ACCUMULATION. THINK THAT MOST
SNOWFALL SHOULD BE OUT OF THE REGION BY SUNRISE SATURDAY...WITH
ISOLATED SNOW SHOWERS REMAINING ACROSS THE RIDGES AS THE COLD FRONT
COMPLETES ITS PASSAGE ACROSS THE REGION. COLD AIR BEHIND THE FRONT
WILL RESULT IN THE COLDEST HIGH TEMPERATURES SO FAR THIS
SEASON...WITH MOST LOCATIONS REMAINING BELOW FREEZING ALL DAY.

OUTLOOK...SATURDAY NIGHT THROUGH WEDNESDAY...
VFR INTO TUESDAY. COLD FRONTAL SHOWERS OF SNOW AND RAIN CAN CAUSE
RESTRICTIONS TUESDAY NIGHT INTO WEDNESDAY.

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

AREA FORECAST DISCUSSION

NWS GRAND RAPIDS MI

918 PM EST FRI DEC 9 2011

LATEST UPDATE...SHORT TERM...

.SYNOPSIS...(300 PM EST FRI DEC 9 2011)
LAKE EFFECT SNOW IS EXPECTED OVERNIGHT WITH LIGHT ACCUMULATIONS.
AFTERWARD DRY CONDITIONS AND MILD TEMPERATURES WILL PREVAIL UNTIL A
LOW PRESSURE SYSTEM BRINGS A MIX OF PRECIPITATION IN THE NEXT
WEDNESDAY TO THURSDAY NIGHT TIMEFRAME.

.SHORT TERM...(918 PM EST FRI DEC 9 2011)
(TONIGHT THROUGH SATURDAY NIGHT)
UPDATED THE GRIDS TO REFLECT LESS IN THE WAY OF PCPN. SHALLOW
MOISTURE IS TAKING IT/S TOLL ON LAKE EFFECT POTENTIAL. DESPITE
MODERATE INSTABILITY RADAR IS SHOWING LITTLE IN THE WAY OF PCPN AND
IR IMAGERY SHOWS CLOUDS HUGGING THE COAST. SHSN THAT DEVLEOP SHOULD
REMAIN WELL WEST OF US-131.

.LONG TERM...(300 PM EST FRI DEC 9 2011)
(SUNDAY THROUGH FRIDAY)
THE MAIN FOCUS FOR THE EXTENDED PERIOD WILL BE ON A POTENTIAL STORM
SYSTEM THAT MAY IMPACT OUR REGION BY LATE WEDNESDAY.

UNTIL THEN...QUIET WEATHER PREVAILS ON SUNDAY WITH A STEADY SW
BREEZE AND MILD TEMPERATURES WITH HIGHS IN THE UPPER 30S. WE DO HAVE
SOME SLIGHT CHANCE POPS TO LOW CHANCE POPS FEATURED MONDAY NIGHT AND
TUESDAY AS A WEAK FRONTAL FEATURE MOVES THROUGH IN RESPONSE TO A
WEAK RIPPLE SEEN ON THE 500MB GEOPOTENTIAL HEIGHT PLOT. MOISTURE
DEPTH IS HELD IN CHECK TO GENERALLY AROUND 10K FT. THE DGZ HOWEVER
WILL BE LOCATED IN THE 13K TO 15K FT RANGE SO SMALL FLAKE GROWTH IS
ANTICIPATED WITH SOME LIGHT RAIN OR DRIZZLE POSSIBLE AS WELL. QPF
AMOUNTS ARE ONLY A FEW HUNDRETHS WITH THIS SYSTEM.

EXTENSIVE COLLABORATION HAS BEEN DONE WITH SURROUNDING OFFICES ON
HOW TO HANDLE THIS POTENTIAL MIDWEEK SYSTEM. THE COMMON THEME HAS
EMERGED THAT WE WILL BE ON THE WARM SIDE OF THIS SYSTEM...BUT THE
TIMING IS STILL IN QUESTION. THE LATEST GFS AND CANADIAN GEM DO NOT
SUPPORT THE ECMWF IN TERMS OF SYSTEM PROPAGATION. WHAT WE`LL BE
WATCHING IS A DIGGING WAVE PROGGED TO BE ACROSS THE DESERT SOUTHWEST
REGION BY MONDAY AND TUESDAY. IT WILL NEARLY GET CUT OFF FROM THE
NORTHERN STREAM ENERGY BUT EVENTUALLY IT LOOKS TO GET PHASED WITH
MORE UPPER LEVEL ENERGY MOVING ACROSS THE PACIFIC NORTHWEST BY
WEDNESDAY. THE LATEST GFS ENSEMBLE MEAN 500MB HEIGHTS SUPPORT THIS
EVOLUTION.

LOOKING AT THE ECMWF ENSEMBLE PLOTS FROM 00Z...UNCERTAINTY EXISTS IN
HOW AND WHEN THIS FEATURE EXITS THE SW UNITED STATES. NORMALIZED
STANDARD DEVIATIONS WITH THIS FEATURE ARE 2.5-5.0...MEANING THERE IS
A GOOD DEAL OF SPREAD WITH HOW THIS SYSTEM IS HANDLED COMPARED TO
CLIMATOLOGY. ALSO...THE ECMWF DETERMINISTIC MODEL OVERLAID WITH THE
ENSEMBLE SPREAD INDICATES THERE IS GOOD CONFIDENCE WITH THE WARM
UPPER LEVEL PATTERN WE WILL EXPERIENCE EARLY TO MID WEEK BUT ABOUT
4-8 STD DEV OF SPREAD AMONGST THE ENSEMBLE MEMBERS ON HOW STRONG
THIS SYSTEM WILL BE BEFORE IT HEADS TOWARD THE MIDWEST.

THE GFS AND GEM HAVE A QUICK MOVING SYSTEM THAT COULD BEGIN TO
AFFECT OUR AREA WITH OVERRUNNING PRECIPITATION BY WEDNESDAY. THIS
CONCERNS ME A BIT BECAUSE WE COULD HAVE A PERIOD OF FREEZING RAIN OR
FREEZING DRIZZLE IF PRECIP GETS HERE TOO QUICK. NOT PUTTING THAT IN
THE FORECAST RIGHT NOW...AND AFTER COLLABORATING WITH SURROUNDING
OFFICES WE ARE FAVORING THE ECWMF IN TERMS OF SYSTEM EVOLUTION (A
BIT SLOWER AND WARMER). STILL COULD SEE A PERIOD OF WINTRY WEATHER
DURING THE ONSET OF PRECIPITATION SO WE`LL NEED TO MONITOR.

LOOKS LIKE A GOOD DOSE OF RAIN IS LIKELY FOR MUCH OF THE REGION AS
THIS SYSTEM DEEPENS TO OUR WEST (GEM SEEMS A BIT OF AN OUTLIER
TAKING THE LOW ACROSS LAKE MICHIGAN THURSDAY). THE GFS ENSEMBLE MEAN
850MB WIND (V-COMPONENT) IS ABOUT 2-3 STD DEVS ABOVE NORMAL AS THIS
SYSTEM NEARS. ALSO...THE GFS DETERMINISTIC MODEL IS SHOWING A
VIGOROUS 70-80KT LLJ POINTED AT OUR AREA ON THURSDAY. THE ECMWF IS
ALMOST AS STRONG. LIKELY POPS ARE CURRENTLY IN THE GRIDS WEDNESDAY
NIGHT AND THURSDAY. COULD SEE SOME COLDER AIR WRAP IN BEHIND THE
SYSTEM WITH A CHANCE FOR SNOW SHOWERS BY FRIDAY.

.AVIATION...(635 PM EST FRI DEC 9 2011)
EXPECTING AN UPTICK IN LAKE EFFECT CLOUDINESS AND SNOW SHOWER
ACTIVITY TONIGHT. RUC13 950-900MB RH PROFILE (ROUGHLY 1K-2K FT)
REVEALS INCREASING SATURATION LATER TONIGHT...SO A TREND TOWARD BKN
AND OVC CIGS IS EXPECTED. HOWEVER...CLOUD BASES SHOULD STAY IN THE
MVFR/VFR CATEGORY WITH LIGHT SNOW SHOWERS EXPECTED. AS MENTIONED IN
THE PREVIOUS DISCUSSION...THERE IS A POSSIBILITY FOR CLOUD BASES
UNDER 2K FT...BUT THIS ACTIVITY SHOULD NOT BE SIGNIFICANT ENOUGH TO
WARRANT ANY IFR CONDITIONS. THIS TREND WILL CONTINUE INTO SATURDAY
MORNING BEFORE MODEL GUIDANCE INDICATES THE CLOUDS WILL MOVE OFF THE
LAKE AND DISSIPATE.

.MARINE...(300 PM EST FRI DEC 9 2011)
LATEST LOCAL RUN OF THE GLERL SUGGESTS THAT SCA CONDITION SHOULD
PREVAIL THROUGH SUNDAY AND POSSIBLY INTO SUNDAY NIGHT AS COLD AIR
AND WEST WINDS 15 TO 25 CREATE HAZARDS TO SMALL CRAFT.

.HYDROLOGY...(300 PM EST FRI DEC 9 2011)
NO SIGNIFICANT PCPN IS EXPECTED UNTIL THE MIDDLE OF THE NEXT WORK
WEEK. RIVER LEVELS WILL SLOWLY FALL.

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY THROUGH SUNDAY FROM ST JOE TO MANISTEE.

SYNOPSIS: TJT
SHORT TERM: 93
LONG TERM: HOVING
AVIATION: HOVING
MARINE: TJT
HYDROLOGY: TJT

AREA FORECAST DISCUSSION...UPDATED

NWS MARQUETTE MI

916 PM EST FRI DEC 9 2011

.UPDATE...

LAKE EFFECT SNOW CONTINUES TO FALL OVER LOCATIONS FAVORED BY A WEST
WIND THIS EVENING. RUC ANALYSIS HAS H850 TEMPS AROUND -15C E AND
-17C WEST...PUTTING MUCH OF THE LLVL OMEGA IN THE DGZ. WITH A SFC
RIDGE OVER MN...DRIER AIR HAS BEEN FILTERING OVER WRN LK SUPERIOR
AND HAS LIKELY BEEN KEEPING LES IN CHECK WITH INVERSION HEIGHTS AOB
5KFT...ALTHOUGH LATEST RADAR SHOWING SOME RETURNS NEAR TWIN LAKES OF
5.5KFT. DECIDED TO LET HEADLINES EXPIRE OVER THE WEST SINCE CALLS
INDICATED ONLY AN INCH OR TWO HAD FALLEN OVER 3-4HRS PRIOR TO THE
ENDING TIME. DID TOY WITH THE IDEA OF EXTENDING THE LES WARNING FOR
NRN HOUGHTON SINCE THERE WILL LIKELY STILL BE A PERIOD OF MODERATE
SNOW OVER THE NEXT FEW HOURS. THIS COULD DROP ANOTHER 1 TO 4 INCHES
FROM TWIN LAKES TOIVOLA BEFORE WINDS TURN TO THE SW OVERNIGHT AND
PUSH THE MAIN BAND N.

OVER THE EAST...HAD SOME INITIAL CONCERN ON THE ADVY DUE TO THE
PERSISTENT SW WINDS OVER NCNTRL UPPER MI AND SCNTRL LK SUPERIOR.
HIGH RES MODELS STILL SHOWING WEAK SFC TROUGH SHIFTING WINDS MORE
OUT OF THE WNW OVER THE NEXT COUPLE OF HOURS WITH THE SFC TROUGH
DROPPING THROUGH...WHICH IS ALREADY SEEN AT ISLE ROYALE AND LATEST
OBS AT KCMX/STDM4 ARE STARTING TO SHOW. THIS HAS FINALLY STARTED TO
PUSH THE LES BAND FARTHER S AND NEAR NE LUCE COUNTY. WITH LONGER
FETCH...LLVL CONVERGENCE AND INVERSION HEIGHTS NEAR 10KFT...EXPECT
MODERATE TO HEAVY SNOW TO OCCUR ONCE THE BAND MOVES ON SHORE. KMQT
RADAR ESTIMATES THIS EVENING IN THE MAIN BAND HAVE HAD 1-2 INCH PER
HOUR SNOWFALL RATES. FEEL FAIRLY CONFIDENT ON ADVISORY FOR LUCE
COUNTY WITH LATEST TRENDS...BUT ALGER MAY BE A LITTLE IFFY...SINCE
DOWNSLOPE SW WINDS OVER MARQUETTE COUNTY ARE HELPING INJECT DRIER
AIR INTO THE SRN EDGE. WILL LEAVE ADVISORY AS IS AND ONLY MADE SOME
MINOR TWEAKS TO THE GOING SNOWFALL FORECAST...MAINLY TO FOCUS MORE
OVER LUCE COUNTY. EXPECT THE LES TO DIMINISH AND PUSH OFF SHORE LATE
TONIGHT INTO TOMORROW MORNING.
&&

PREV DISCUSSION...ISSUED AT 627 PM EST FRI DEC 9 2011...

.SHORT TERM /THROUGH 00Z SUNDAY/...

WITH A DEEP UPPER TROUGH OVER THE REGION THIS AFTERNOON...THE
COOLEST AIR OF THE SEASON IS CHILLING OUT OVER THE CWA. LOWS LAST
NIGHT FELL INTO THE SINGLE DIGITS AND TEENS OVER LAND AREAS...AND
LIKELY BELOW ZERO IN TYPICAL COLD SPOTS OVER THE INTERIOR WEST.
HIGHS TODAY SHOULD BE IN THE TEENS TO LOW 20S. WEST WIND LES THAT
HAS BEEN HITTING THE WRN AND OCCASIONALLY FAR NERN CWA IS CHANGING
ORIENTATION TODAY AS A RIDGE OF HIGH PRESSURE SLOWLY MOVES TOWARD
THE CWA FROM THE W. THIS IS CAUSING WINDS TO BE MORE FROM THE
WNW...WHICH IS ACTING TO BRING LES BANDS INTO THE FAR NERN CWA EAST
OF MUNISING.

THE SFC RIDGE AXIS WILL MOVE TO WRN LAKE SUPERIOR BY 06Z SAT...AND
TO CENTRAL LAKE SUPERIOR BY 18Z SAT. THIS WILL PUSH MOST LES
OFFSHORE FROM A SW WIND SATURDAY MORNING...EXCEPT OVER THE KEWEENAW
WHICH MAY SEE SOME LINGERING PATCHY LES THROUGH SAT.

THE TRICKIEST PART OF THE SHORT TERM IS WITH LES EAST OF MUNISING.
FINE SCALE MODELS SHOW THE STRONG LES BAND...CURRENTLY MAKING
LANDFALL OVER THE NERN CWA...LINGERING LONG ENOUGH TO PRODUCE
ADVISORY SNOWFALL AMOUNTS OF 5 TO 8 INCHES IN 12 HOURS NEAR LAKE
SUPERIOR. HAD HIGH ENOUGH CONFIDENCE TO ISSUE LES ADVISORY FOR ALGER
AND LUCE COUNTIES GIVEN RADAR AND SAT TRENDS SHOWING THE BAND
MOVING S FROM WNW WINDS...BUT UNCERTAINTY REMAINS AS TO HOW LONG THE
BAND WILL SIT OVER ANY ONE AREA BEFORE IT MOVES OUT SAT MORNING.

TONIGHT LOOKS TO BE PRETTY COLD AS THE HIGH MOVES IN BRINGING CLEAR
SKIES AWAY FROM LAKE SUPERIOR. MAJORITY OF GUIDANCE SHOWS TEMPS
FALLING BELOW ZERO TONIGHT INLAND. UPSTREAM TEMPS OVER MN FELL TO
THE MID SINGLE DIGITS BELOW ZERO LAST NIGHT...WHICH SEEMS QUITE
REASONABLE FOR INLAND AREAS OF UPPER MICHIGAN TONIGHT.

.LONG TERM DISCUSSION /SAT NGT THRU FRI/...

SAT NGT/SUN...CWA WL BE DOMINATED BY STRONG WSW FLOW BTWN HI PRES IN
THE OH RIVER VALLEY/MID ATLANTIC STATES AND LO PRES CROSSING SCNTRL
CAN/NW ONTARIO TOWARD JAMES BAY BY LATE SUN. EXPECT AN AREA OF WAD
CLD ASSOCIATED WITH H85 WINDS INCRSG TO NEAR 50KTS/SHARP ISENTROPIC
ASCENT ON THE 280-290K SFCS /H85-7/ OVER THE E ON SAT EVNG TO SHIFT
AWAY THE AREA AS THE WAD CONTRIBUTES TO HORIZONTAL WARMING INSTEAD
OF UPWARD MOTION. IN FACT...H85 TEMPS ARE FCST TO RISE FM -3C/-10C
AT IWD/ERY AT 00Z SUN TO 6C/0C AT 12Z SUN. H85 TEMPS ARE FCST TO
LINGER ARND 5C THE WHOLE DAY ON SUN. SINCE THE INCOMING WARMER
AIRMASS WL ALSO BE QUITE DRY...SKIES SHOULD TREND MOCLR AFT THE WAD
CLD EXITS TO THE E. HOW MUCH OF THE H85 WARMING GETS MIXED TO THE
SFC IS CRITICAL IN DETERMINING HOW TEMPS RISE AT THE SFC ON SUN.
WITH HI STABILITY SHOWN ON FCST SDNGS AND LO SUN ANGLE...TENDED
TOWARD THE LOWER END OF GUIDANCE FOR TEMPS ON SAT NGT AND SUN. EVEN
SO...MOST PLACES WL LIKELY SEE THE MERCURY CLIMB WELL INTO THE
30S...WARMEST IN THE DOWNSLOPE AREA NEAR LK SUP. BUT THE STIFF WSW
WIND WL MAKE THE AIR FEEL COLDER.

SUN NGT...WITH APRCH OF LO PRES TROF/COLD FNT ATTENDANT TO SFC LO
MOVING INTO QUEBEC...THE STRONGER SW WINDS WL DIMINISH ON SUN NGT.
BUT MODELS BEGIN TO SHOW LLVL MSTR RETURNING AHEAD OF THIS TROF...
SO EXPECT LO CLDS TO ARRIVE. SINCE THE MID LVLS ARE FCST TO REMAIN
DRY WITH AN ABSENCE OF MID LVL FORCING UNDER A BIT OF AN H5 RDG
AXIS...ANY PCPN WOULD LIKELY BE IN THE FORM OF FZDZ AS FCST SDNGS
SHOW MSTR WELL BLO THE DGZ.

MON/MON NGT...WITH THE APRCH OF LO PRES TROF AND A SHRTWV FM THE W
AS WELL AS INCRSG AND DEEPER MSTR RETURN...EXPECT AN INCRSG CHC OF
PCPN ON MON. PCPN INTENSITY WL BE LIMITED BY RELATIVELY SHALLOW
NATURE OF DEEPER MSTR THAT REMAINS FOR THE MOST PART BLO A HIER DGZ
CENTERED ARND 12K FT. A FAIRLY WARM BLYR MAY SUPPORT AT LEAST A MIX
WITH RA OVER PORTIONS OF THE E HALF ON MON PER SOMEWHAT WARMER
NAM...BUT ANY PCPN WL TURN TO SN ON MON NGT WITH THE ARRIVAL OF
SOMEWHAT COLDER AIR IN THE CYC NLY FLOW LEFT IN THE WAKE OF THE
SLOWLY DEPARTING DISTURBANCE. AS THE SHRTWV/DEEPER MSTR EXIT TO THE
E ON MON NGT...PCPN CHCS WL DIMINISH W-E BUT NOT END COMPLETELY WITH
LINGERING CYC FLOW. H85 TEMPS FALLING INTO THE -6C TO -8C WL BE
MARGINAL FOR LES...BUT CYC FLOW MAY ACT AS A WEAK ENHANCEMENT
MECHANISM.

EXTENDED FCST...THIS PERIOD WL BE DOMINATED BY A BLDG RDG OVER THE
SE CONUS...WHICH WL FORCE A HEALTHY NEGATIVELY TILTED SHRTWV/SFC LO
TO RIDE NEWD FM THE PLAINS INTO THE GRT LKS ON WED-THU. PER NCEP
DISCUSSION...FAVORED THE FARTHER W TRACK FOR THIS LO AS SHOWN BY 12Z
GFS/ECMWF. THIS TRACK WOULD SUPPORT A WINTRY MIX OF PCPN FOLLOWED BY
SOME LES ON FRI AS COLDER AIR RETURNS IN THE WAKE OF THE DEPARTING.
OVERALL...TEMPS WL AVG WELL ABV NORMAL FOR THE SEASON DURING THIS
TIME.
&&

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

ONGOING WESTERLY LAKE EFFECT SNOW WILL CONTINUE TO AFFECT KCMX
THROUGH THE NIGHT...BEFORE ENDING TOMORROW MORNING. EXPECT MAINLY
MVFR CONDITIONS THROUGH THE NIGHT...BUT COULD BE A COUPLE PERIODS
WHERE ALTERNATE LANDING MINS ARE REACHED...EARLY THIS EVENING AND
AGAIN LATE TONIGHT AS THE DOMINATE BAND OVER CENTRAL HOUGHTON COUNTY
SHIFTS N ACROSS THE KEWEENAW. OTHERWISE...EXPECT VFR CONDITIONS AT
THE OTHER TWO SITES...DUE TO UNFAVORABLE WIND DIRECTIONS. A WEAK LOW
PRESSURE SYSTEM MOVING INTO THE NRN PLAINS WILL BRING INCREASING
CLOUDS TO ALL SITES ON SAT...BUT EXPECT CIGS TO BE VFR.
&&

.MARINE /FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE/...

WITH STRONG WINDS AND COLD TEMPERATURES...FREEZING SPRAY WILL REMAIN
POSSIBLE INTO SATURDAY MORNING. A HIGH PRESSURE SYSTEM WILL DIVE SE
FROM THE PLAINS STATES TO THE MID MISSISSIPPI VALLEY BY
SATURDAY...BEFORE EXITING TO THE CENTRAL APPALACHIANS AND MID
ATLANTIC SUNDAY. THE RESULT ACROSS LS WILL BE A RIDGE THROUGH
SATURDAY. EVEN WITH A RIDGE OF HIGH PRESSURE OVERHEAD...THE PRESSURE
GRADIENT BETWEEN THE LOW TO OUR NORTH AND HIGH PRESSURE ROUNDING THE
AREA TO THE SOUTH WILL KEEP STRONG WINDS OF 20 TO 30KTS IN THE
FORECAST THROUGH SUNDAY NIGHT. SW GALE FORCE GUSTS TO 35KTS WILL BE
POSSIBLE SATURDAY MAINLY OVER WESTERN LAKE SUPERIOR AS THE HIGH
EXITS TO OUR SE AND LOW PRESSURE NEARS FROM CANADA. THIS LOW OVER
SOUTH CENTRAL CANADA SATURDAY NIGHT WILL SLIDE ACROSS EASTERN
ONTARIO SUNDAY NIGHT...WITH A TROUGH EXTENDING SOUTHWESTWARD FROM
THE LOW. EXPECT THE TROUGH TO STALL OUT ACROSS THE UPPER GREAT LAKES
MONDAY THROUGH TUESDAY MORNING...BEFORE A RIDGE BUILDS BACK IN FROM
THE WEST LATE IN THE DAY TUESDAY. A LOW PRESSURE SYSTEM WILL BEGIN
TO MOVE TOWARD THE AREA FROM THE CENTRAL PLAINS STATES...BUT THERE
REMAINS UNCERTAINTY AS TO THE EXACT TRACK AND STRENGTH OF THE SYSTEM.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 9 AM EST SATURDAY FOR MIZ006-007.

LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

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

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

1231 PM EST THU DEC 8 2011

UPDATED AVIATION DISCUSSION FOR 18Z TAFS

.SYNOPSIS /ISSUED AT 545 AM/...
WV IMAGERY AND RUC ANALYSIS INDICATED CYCLONIC MID/UPPER LEVEL FLOW
AROUND A VORTEX OVER HUDSON BAY BRINGING NRN STREAM WNW FLOW FROM
SRN CANADA INTO THE UPPER GREAT LAKES. A SHORTWAVE MOVING THROUGH
THE UPPER GREAT LAKES EARLY THIS MORNING ALONG WITH ITS ASSOC SFC
TROUGH IS HELPING TO FOCUS AN INTENSE LAKE ENHANCED SNOW BAND OVER
SOUTH CENTRAL LAKE SUPERIOR AND THE ERN UPR MI SHORELINE IN THE PAST
HR AS NOTED ON RADAR IMAGERY. A STRONG 140 KT UPR JET MAX DIVING
DOWN THROUGH ALBERTA WILL HELP AMPLIFY MID-UPR LVL TROF OVER THE
UPPER GREAT LAKES LATE TONIGHT AND FRIDAY AS WELL AS POSSIBLY BRING
SOME ENHANCEMENT TO LES BANDS OVER LAKE SUPERIOR. ABUNDANT DRY AIR
UPSTREAM OVER THE NRN PLAINS AS NOTED ON SATELLITE IMAGERY AND SFC
OBS HAS THUS FAR INHIBITED ORGANIZATION OF LES BANDS OVER WRN LAKE
SUPERIOR DESPITE ADVECTION OF -15C 850 TEMPS INTO AREA.
&&

.DISCUSSION...

MAIN CONCERN IS LES POTENTIAL AND ONGOING HEADLINES OVER WRN UPR MI
INTO FRIDAY.

CONCERN TODAY WILL BE ABUNDANT DRY AIR UPSTREAM...WHICH IS DEPICTED
FAIRLY WELL BY GFS BUFR SNDGS...AND HOW MUCH THIS DRY AIR WILL
NEGATIVELY AFFECT ORGANIZATION OF LES BANDS AND THUS POTENTIAL FOR
HEAVY SNOW ACCUMULATION AT LEAST TODAY. ALL 00Z MODELS INCLUDING
LOCAL MESOSCALE MODELS ARE LESS BULLISH ON LAKE EFFECT QPF THAN PREV
RUNS AND AGAIN THIS IS LIKELY DUE TO DRIER AIR UPSTREAM OF THE LAKE
AND LACK OF SYNOPTIC SCALE FORCING. EVEN THOUGH SNOW GROWTH REMAINS
GENERALLY FAVORABLE WITH 25-30/1 SNOW WATER RATIOS
EXPECTED...GENERALLY DECIDED TO TRIM BACK LES ACCUMS TO 2 TO LOCALLY
5 INCHES OVER WARNING AND ADVISORY AREAS OF NRN ONTONAGON...HOUGHTON
AND KEWEENAW COUNTIES TODAY DUE TO IMPACTING DRY AIR. GUSTY WEST
WINDS TO 30 MPH WILL LIKELY CAUSE CONSIDERABLE BLOWING SNOW AND
REDUCED VSBYS IN ANY MODERATE LES BANDS THAT FORM OVER HEADLINE
REGIONS.

LOCATIONS NEAR LAKE SUPERIOR EAST OF MUNISING...FROM GRAND MARAIS TO
TWO HEART MAY ALSO SEE A PERIOD OF BRIEF HEAVY SNOW EARLY THIS
MORNING WITH BAND MOVING ACROSS ERN LAKE SUPERIOR ATTM. AS MENTIONED
BEFORE PLENTY OF UNCERTAINTY EXISTS WITH EVOLUTION OF LES BANDS
TODAY AND WHETHER ANY HEAVIER WILL MOVE INLAND OR OFFSHORE...SO NO
HEADLINES WERE ISSUED FOR ERN COUNTIES AT THIS TIME.

LARGE SCALE TROUGH WITH COLDEST AIR OF SEASON THUS FAR TO PUSH INTO
THE AREA TONIGHT INTO FRIDAY. MODELS NOT DEPICTING MUCH IN THE WAY
OF ANY SIGNIFICANT SHORTWAVES THAT WOULD AID IN ENHANCEMENT TO LES
BANDS. HOWEVER...COMBINATION OF POSSIBLE WEAK ENHANCEMENT WITH
ARRIVAL OF TROUGH...H85 TEMPS LOWERING TO AROUND -18C BY 12Z FRIDAY
AND INCREASING LOW-LVL CONVERGENCE FROM NIGHTTIME LAND BREEZES...MAY
BE JUST ENOUGH TO ORGANIZE FORMATION OF DOMINANT BAND OVER SRN LAKE
SUPERIOR AS DEPICTED BY 00Z MODELS. INTERESTINGLY ENOUGH...MODEL AVG
QPF NOT AS HEAVY AS PREV RUNS FOR TONIGHT INTO FRIDAY MORNING...AND
THIS IS AGAIN LIKELY TO DUE TO AFFECTS OF VERY DRY AIR UPSTREAM.
STILL WOULD EXPECT TOTAL SNOW ACCUMS TO EXCEED A FOOT AT FAVORED
HIGHER TERRIAN LOCATIONS THROUGH ENTIRE EVENT. WRN INTERIOR
LOCATIONS MAY DIP CLOSE TO ZERO TONIGHT WHILE HIGHS ON FRIDAY WILL
STAY MAINLY IN THE LOWER TEENS.

BY LATE FRIDAY...WEAKER TROUGH FCST TO SLIDE THROUGH THE AREA MAY
VEER WINDS SLIGHTLY MORE NW LEADING TO INCREASED CHANCES OF DOMINANT
LES BAND MOVING INTO FAR EASTERN SECTION OF CWA...MAINLY EAST OF
MUNISING AND WELL NORTH OF NEWBERRY. SOME MODERATE TO POSSIBLE HEAVY
SNOWFALL COULD WARRANT A HEADLINE AT SOME POINT FOR THESE COUNTIES.

TROUGH AND COLDER AIR SFC-H85 SLOWLY HEAD INTO LOWER GREAT LAKES
FRIDAY NIGHT INTO SATURDAY. WARM AIR ADVECTION STARTS UP BY SATURDAY
LEADING TO A PUSH OF ISENTROPIC ASCENT 285-290K (750-650MB) ACROSS
MUCH OF THE CWA...BUT LIMITED MOISTURE SHOULD KEEP CWA DRY. LES
BANDS WILL PUSH OFFSHORE BY LATE FRI NIGHT INTO EARLY SATURDAY AS
GUSTY SW WINDS LOWERS WIND CHILL VALUES IN THE MORNING DESPITE SFC
TEMPS REBOUNDING INTO LOWER TO MIDDLE 20S SAT AFTERNOON.

MODELS STILL IN AGREEMENT WITH SHORTWAVE AND PASSAGE OF FRONTAL
BOUNDARY BRINGING ANOTHER CHC OF SNOW..POSSIBLY MIXED WITH RAIN EAST
HALF ON MONDAY WITH SOME LINGERING LIGHT SNOW POSSIBLE MON NIGHT
INTO TUE.
&&

.AVIATION /FOR THE 18Z TAF ISSUANCE/...

A CONTINUED WESTERLY FLOW OF COLD AIR ACROSS THE WARM WATERS OF LAKE
SUPERIOR...AND INCREASED LIFT FROM THE TERRAIN ENHANCEMENT OF THE
KEWEENAW PENINSULA WILL AID IN KEEPING LAKE EFFECT SNOW SHOWERS IN
PLACE AT CMX. LIFR TO VLIFR VIS WILL REMAIN POSSIBLE...PARTICULARLY
WITH BLSN THANKS TO GUSTY WINDS OVER 30KTS. FARTHER TO THE SOUTH...A
LESS FAVORABLE WIND DIRECTION AT IWD WILL MAINLY RESULT IN A FEW
FLAKES OF SNOW...AND HIGH END MVFR CEILINGS AND VIS. SOME SNOW
SHOWERS MAY BE ABLE TO SLIDE TO SAW LATER TODAY AND TONIGHT...BUT
WILL REMAIN LIGHT...WITH HIGH END MVFR POSSIBLE IN THE HEAVIER BANDS
THERE. KEPT ANY SNOW OUT OF THE TAF AT SAW AS MUCH OF THE SNOW WILL
REMAIN OFFSHORE.
&&

.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...

THE UPPER GREAT LAKES WILL REMAIN BETWEEN STRONG A LOW ACROSS HUDSON
BAY...AND STRONG HIGH PRESSURE OVER W CANADA AND THE NORTHERN PLAINS
THROUGH TONIGHT...WITH WESTERLY GALES TO 35KTS CONTINUING INTO THE
EVENING HOURS. EXPECT THE HIGH TO SLIDE TO THE CENTRAL PLAINS
OVERNIGHT...BEFORE SHIFTING TO THE OHIO VALLEY AND MID ATLANTIC THIS
WEEKEND. THE RESULT WILL BE A RIDGE SLIDING OVER THE UPPER GREAT
LAKES FRIDAY AND FRIDAY NIGHT...WEAKENING OVER THE WEEKEND. LOW
PRESSURE ACROSS SOUTH CENTRAL CANADA SUNDAY MORNING SHOULD SLOWLY
PUSH ACROSS LS AND MANITOBA MONDAY AFTERNOON THROUGH TUESDAY. OUT
AHEAD OF THIS LOW...STRONG SW WINDS AND POSSIBLY GALES TO 35KTS WILL
BE POSSIBLE SATURDAY.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST FRIDAY FOR MIZ002-003.

LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST FRIDAY FOR MIZ001-084.

LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EST FRIDAY FOR LSZ263>267.

GALE WARNING UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR
LSZ241>244.

LAKE MICHIGAN...
NONE.
&&

SYNOPSIS...VOSS
DISCUSSION...VOSS
AVIATION...TITUS
MARINE...KF

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

640 AM EST THU DEC 8 2011

UPDATED AVIATION DISCUSSION FOR 12Z TAFS

.DISCUSSION...

MAIN CONCERN IS LES POTENTIAL AND ONGOING HEADLINES OVER WRN UPR MI
INTO FRIDAY.

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

A CONTINUED WESTERLY FLOW OF COLD AIR ACROSS THE WARM WATERS OF LAKE
SUPERIOR...AND INCREASED LIFT FROM THE TERRAIN ENHANCEMENT OF THE
KEWEENAW PENINSULA WILL AID IN KEEPING LAKE EFFECT SNOW SHOWERS IN
PLACE AT CMX. LIFR CEILINGS AND VIS WILL REMAIN
POSSIBLE...PARTICULARLY WITH BLSN THANKS TO GUSTY WINDS OVER 30KTS.
FARTHER TO THE SOUTH...A LESS FAVORABLE WIND DIRECTION AT IWD WILL
MAINLY RESULT IN A FEW FLAKES OF SNOW...AND HIGH END MVFR CEILINGS
AND VIS. SOME SNOW SHOWERS HAVE BEEN ABLE TO SLIDE TO SAW...BUT HAVE
REMAINED LIGHT AND SHELTERED SO FAR...WITH HIGH END MVFR POSSIBLE IN
THE HEAVIER BANDS THERE AS WELL AS MUCH OF THE SNOW REMAINS OFFSHORE.
&&

.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST FRIDAY FOR MIZ002-003.

LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST FRIDAY FOR MIZ001-084.

LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EST FRIDAY FOR LSZ263>267.

GALE WARNING UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR
LSZ241>244.

LAKE MICHIGAN...
NONE.
&&

SYNOPSIS...VOSS
DISCUSSION...VOSS
AVIATION...KF
MARINE...KF

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

624 AM EST THU DEC 8 2011

.DISCUSSION...

MAIN CONCERN IS LES POTENTIAL AND ONGOING HEADLINES OVER WRN UPR MI
INTO FRIDAY.

.AVIATION /FOR THE 06Z TAF ISSUANCE/...

PASSAGE OF THE FIRST IN A SERIES OF LO PRES TROF WL BRING IFR
CONDITIONS TO THE EXPOSED CMX LOCATION THAT WL EXPERIENCE MORE SGNFT
LK MOISTENING DESTABILIZATION EARLY THIS MRNG. ALTHOUGH THERE MAY BE
SOME -SHSN AT IWD AND SAW...ANY REDUCED CIG/VSBY WL BE MORE LIMITED
WITH LESS LK MODIFICATION AND/OR DOWNSLOPE WIND COMPONENT. EXPECT A
PERIOD OF IMPROVEMENT TOWARD SUNRISE AS A TRAILING SFC HI PRES
RDG/AXIS OF DRIER AIR FOLLOWING THE TROF SHIFTS OVHD. BUT THE LULL
WL BE ONLY TEMPORARY WITH A SECOND LO PRES TROF FOLLOWING THRU AT
MID MRNG. THIS DEEPER TROF WL BE FOLLOWED BY STRONGER W WINDS THAT
WL CAUSE GUSTS AS HI AS 30 KT OVER THE EXPOSED KEWEENAW/CMX. THE
COMBINATION OF FALLING LK EFFECT SN AND BLSN WHIPPED UP BY THESE
STRONG WINDS WL LIKELY LEAD TO LIFR CONDITIONS AT THAT SITE. THE DRY
NATURE OF THE ARCTIC AIRMASSES WL LIMIT DETERIORATION AT IWD AND
ESPECIALLY SAW...WHERE THE PREVAILING WLY WIND COMPONENT WL
DOWNSLOPE/DRY AND RESULT IN PREDOMINANT VFR CONDITIONS.
&&

.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST FRIDAY FOR MIZ002-003.

LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST FRIDAY FOR MIZ001-084.

LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EST FRIDAY FOR LSZ263>267.

GALE WARNING UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR
LSZ241>244.

LAKE MICHIGAN...
NONE.
&&

SYNOPSIS...VOSS
DISCUSSION...VOSS
AVIATION...KF
MARINE...KF

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

1234 AM EST THU DEC 8 2011

UPDATED AVIATION DISCUSSION FOR 06Z TAFS

.SYNOPSIS /ISSUED AT 354 PM/...
WV IMAGERY AND RUC ANALYSIS INDICATED CYCLONIC MID/UPPER LEVEL FLOW
AROUND A VORTEX OVER HUDSON BAY BRINGING NRN STREAM WNW FLOW FROM
SRN CANADA INTO THE UPPER GREAT LAKES. AN UPSTREAM SHORTWAVE TROUGH
WAS MOVING THROUGH SRN MANITOBA WITH ANOTHER TRAILING SHRTWV OVER
NRN SASK. AT THE SFC...WINDS WERE VEERING W TO WNW BEHIND A
TROUGH/FRONT THAT MOVED THROUGH THIS MORNING. A TRAILING ARCTIC
FRONT NEAR LAKE WINNIPEG WAS DROPPING TOWARD THE AREA WITH MUCH
COLDER AIR BEHIND IT WITH TEMPERATURES FROM -5 TO 5F OVER NORTHERN
MANITOBA/SASK. VIS LOOP INDICATED CLEARING SKIES OVER THE WEST HALF
OF THE CWA AS DRIER AIR MOVES INTO THE REGION. EVEN WITH 850 MB
TEMPS AROUND -11C...SKIES HAD CLEARED OVER MUCH OF WRN LAKE SUPERIOR.
&&

.SHORT TERM...TONIGHT AND THURSDAY

CLOUDS AND SCT LIGHT LAKE EFFECT SNOW SHOWERS ARE EXPECTED TO
REDEVELOP OVER WRN LAKE SUPERIOR INTO WRN UPPER MI THIS EVENING AS
GREATER LOW LEVEL MOISTURE MOVES TOWARD THE AREA...PER VIS LOOP.
PASSAGE OF THE SASK SHRTWV AND ARCTIC FRONT THU MORNING WITH
INCREASING 850-700 MB MOISTURE AND INVERSION HEIGHTS CLIMBING AROUND
8K FT WILL PROVIDE A SIGNIFICANT BOOST TO THE LAKE EFFECT SNOW. SNOW
GROWTH ALSO LOOKS FAVORABLE AS THE DGZ WILL BE RIGHT IN THE BEST
OMEGA/UPWARD MOTION. GIVEN MODEL QPF AND SNOW/WATER RATIOS
APPROACHING 30/1 WOULD NOT BE SURPRISED TO SEE PERIODS OF MODERATE
TO HEAVY SNOWFALL. THE MOST PERSISTENT LOW LEVEL CONV AND CHANCE FOR
GREATEST ACCUMULATION IS EXPECTED FROM FAR NE ONTONAGON COUNTY INTO
CENTRAL HOUGHTON COUNTY...FROM GREENLAND TO TWIN LAKES. INCREASINGLY
CONVERGENT WRLY FLOW. INCREASING WINDS GUSTING TO NEAR 30 MPH AT
TIMES ON THURSDAY WILL ALSO SHARPLY REDUCE VSBYS IN BLOWING SNOW AS
WELL AND CAUSE DRIFTING SNOW ACROSS THE ROADS. SO...WITH THE
LIKELIHOOD OF AN EXTENDED PERIOD OF LES...HEAVY SNOW AT TIMES...A
LAKE EFFECT SNOW WARNING WAS ISSUED. CONFIDENCE IN ACCUMULATIONS BY
LATE THURSDAY IS LIMITED BY UNCERTAINTY ON WHERE THE HEAVIER BANDS
WILL DEVELOP AND HOW LONG THEY WILL PERSIST. SNOWFALL GENERALLY FROM
3 TO 7 INCHES IS LIKELY WITH SOME HIGHER LCL AMOUNTS.

LOCATIONS NEAR LAKE SUPERIOR EAST OF MUNISING...FROM GRAND MARAIS TO
TWO HEART MAY ALSO SEE A PERIOD OF HEAVIER LES IF THE EXPECTED
DOMINANT BAND SAGS SOUTHWARD WITH SLIGHTLY VEERING WINDS THU.
UNCERTAINTY REMAINS WHETHER THE HEAVIER SNOW WILL REMAIN OFFSHORE OR
MOVE INLAND...SO NO HEADLINES WERE ISSUED AT THIS TIME.

.LONG TERM /THURSDAY NIGHT THROUGH NEXT WEDNESDAY/...

SIGNIFICANT LAKE EFFECT SNOW IS THE MAIN CONCERN FOR THE INITIAL
PORTION OF THE LONG TERM.

LARGE SCALE TROUGH WITH COLDEST AIR OF SEASON THUS FAR TO PUSH INTO
THE AREA SETTLES OVER MUCH OF THE EASTERN CONUS TO END THE WEEK.
NOT MUCH IN THE WAY OF LARGER SCALE SHORTWAVES THAT WILL BRING
WIDESPREAD SNOW TO THE AREA...BUT SIGNIFICANT LK EFFECT FOR WEST
FLOW AREAS IS LIKELY AS H85 TEMPS TUMBLE TO AROUND -18C BY FRIDAY.
MODEL SOUNDINGS INDICATE LAKE INDUCED CAPES AOA 600J/KG WHILE LAKE
EQUIBRIUM LEVELS ARE OVR 10 KFT AGL. HIGHER OVERWATER INSTABILITY
IS SUPPLEMENTED BY STRONG LOW-LEVEL (SFC-H95) CONVERGENCE.

MODELS ARE ACTUALLY IN VERY GOOD AGREEMENT WITH OVERALL SCENARIO
THOUGH SUBTLE SHIFTS IN BLYR WINDS MAKE ALL THE DIFFERENCE AS TO
THE LOCATIONS THAT END UP WITH THE HIGHEST SNOW AMOUNTS. BY LATE
THURSDAY AND INTO THURSDAY NIGHT...SHEAR WITHIN THE SFC-H8 LAYER
IS QUITE LOW...LEADING TO BETTER CHANCE THAT DOMINANT BANDS CAN
ORGANIZE. WINDS BECOMING WESTERLY AT 925MB WITH WSW OR SW SFC WINDS
OVR UPR MI (ENHANCED BY NIGHTTIME LAND BREEZES) WOULD FAVOR STRONGEST
CONVERGENCE/HEAVIER SNOW BANDS OVR WESTERN UPR MI FM ONTONAGON
THROUGH TWIN LAKES/PAINESDALE. WARNING WILL CONTINUE FOR THOSE AREAS
THROUGH LATE FRIDAY FOR THIS PROLONGED HEAVY LAKE EFFECT SNOW EVENT.
STORM TOTALS OVER A FOOT SEEM PRETTY LIKELY IF THE PRIMARY SNOW BAND
STAYS STATIONARY FOR REASONABLE AMOUNT OF TIME.

HIGHER TERRAIN AREAS OF REST OF HOUGHTON COUNTY WILL ALSO SEE
OFF-AND-ON HEAVIER SNOW SHOWERS. ALSO EXPECT SOME HEAVIER SNOW TO
OCCUR OVR SOUTHERN PORTIONS OF HOUGHTON COUNTY...MAINLY NORTH OF
M-38. ADVY WILL COVER THIS POSSIBILITY. EXPECT VERY LITTLE IF ANY
SNOW TOWARD KENTON/SIDNAW ALONG M-28. KEWEENAW COUNTY IS MORE OF A
QUESTION MARK AS THE MORE WNW BLYR WINDS THERE ARE NOT AS FAVORABLE.
STILL THOUGH...DEGREE OF INSTABILITY AND SUFFICIENT MOISTURE PRESENT
COULD LEAD TO LOCALIZED HEAVY AMOUNTS OVR HIGHER TERRAIN THERE AS
WELL. AN ADVISORY WILL HANDLE THIS FOR NOW...THOUGH LATER UPGRADE
COULD BE NEEDED. EXPECT QUIET WEATHER FOR REST OF THE CWA THURSDAY
NIGHT INTO FRIDAY. TEMPS WILL BE ON THE CHILLY SIDE THOUGH WITH
NIGHTTIME LOWS THURSDAY NIGHT TOWARD THE ZERO MARK OVR INTERIOR SW
UPR MI AND HIGHS ON FRIDAY MAINLY STAYING IN THE TEENS.

BY LATE FRIDAY...WEAKER TROUGH FCST TO SLIDE THROUGH THE AREA MAY
VEER WINDS TO MORE NW LEADING TO INCREASED CHANCES OF LAKE EFFECT
SNOW SHOWERS INTO FAR EASTERN SECTION OF CWA...MAINLY EAST OF
MUNISING AND WELL NORTH OF NEWBERRY. LAKE EFFECT SNOW PARAMETER
DEVELOPED BY NWS GAYLORD WHICH INCORPORATES 1000-850MB
SHEAR/850-700MB RH/H85 TEMPS INDICATES FAVORABLE SETUP FOR HEAVY
SNOW RATES IN THOSE EASTERN AREAS FRIDAY AFTN/FRIDAY EVENING.
SNOWFALL RATES UP TO 2 INCHES PER HOUR COULD OCCUR IN THOSE AREAS
AND HEADLINES MAY BE NEEDED AT SOME POINT. HOWEVER...WILL LEAVE
THOSE DECISIONS TO LATER SHIFTS AS EXPECT VERY LITTLE SNOWFALL IN
THOSE AREAS THROUGH FRIDAY MORNING.

TROUGH AND COLDER AIR SFC-H85 SLOWLY HEAD INTO LOWER GREAT LAKES
FRIDAY NIGHT INTO SATURDAY. WARM AIR ADVECTION STARTS UP BY SATURDAY
LEADING TO A PUSH OF ISENTROPIC ASCENT 285-290K (750-650MB) ACROSS
MUCH OF THE CWA. UVM IN THE LAYER FAIRLY STRONG...BUT TROUBLE IS
THERE IS DRY AIR LINGERING BLO H85 THRU THE DAY. COULD BE SOME
FLURRIES OR LIGHT SNOW SHOWERS...BUT BETTER SATURATION WILL KEEP THE
GREATER CHANCE OF ACCUMULATING SNOWS MORE INTO ONTARIO. GUSTY SW
WINDS WILL ADD CHILL TO THE AIR DESPITE SFC TEMPS REBOUNDING INTO
LOWER TO MIDDLE 20S.

FOR THE EXTENDED...TROUGH THAT WAS OVER THE AREA FOR MUCH OF THIS
WEEK IS FCST TO EASE INTO EASTERN CANADA LEADING TO MORE OF A ZONAL
FLOW PATTERN/WARMING TREND BY EARLY NEXT WEEK. WEAK SHORTWAVE/WARM
FRONT SLIDES ACROSS UPR LAKES MONDAY BUT MOISTURE IS MINIMAL SO DO
NOT EXPECT A WHOLE LOT OF PRECIPITIATON. BETTER CHANCE OF
PRECIPITATION WOULD BE FARTHER NORTH CLOSER TO H85-H7 FRONTOGENESIS
AND RIGHT ENTRANCE REGION OF UPR JET OVR ONTARIO. ANOTHER TROUGH
FORMING OVR SCNTRL CANADA IS FCST TO MOVE ACROSS THE UPR GREAT LAKES
LATE TUESDAY INTO WEDNESDAY. DIFFERENCES BEGIN TO APPEAR WITH REGARD
TO DEPTH OF TROUGH BY WEDNESDAY. LAST TWO RUNS OF GFS CLOSED THE
TROUGH OFF OVR UPR MISSISSIPPI RIVER VALLEY/UPR LAKES. MEANWHILE...
RECENT RUNS OF THE ECMWF AND PREVIOUS RUNS OF GFS INDICATED MORE OF
A PROGRESSIVE SYSTEM...WITH DEEPER SYSTEM FORMING OVR CNTRL PLAINS
MID-LATE NEXT WEEK. ENSEMBLES FM GFS/ECMWF/CANADIAN SHED LITTLE
LIGHT ON THE SUBJECT WITH MIXED SIGNALS IN TERMS OF STRENGTH AND
MOVEMENT OF THE TROUGHS. DOES SEEM THAT AT LEAST ECMWF WOULD SUPPORT
BETTER CHANCE OF ORGANIZED PRECIPITATION IN THE MIDWEEK TIME FRAME.
WILL NOT PUT TOO MUCH EMPHASIS ON THIS YET THOUGH AS SUPPORT FOR
THAT IDEA REMAINS LIMITED SUPPORT LOOKING AT OTHER AVILABLE GUIDANCE
AND ENSEMBLES.
&&

.AVIATION /FOR THE 06Z TAF ISSUANCE/...

PASSAGE OF THE FIRST IN A SERIES OF LO PRES TROFS WL BRING IFR
CONDITIONS TO THE EXPOSED CMX LOCATION THAT WL EXPERIENCE MORE SGNFT
LK MOISTENING DESTABILIZATION EARLY THIS MRNG. ALTHOUGH THERE MAY BE
SOME -SHSN AT IWD AND SAW...ANY REDUCED CIG/VSBY WL BE MORE LIMITED
WITH LESS LK MODIFICATION AND/OR DOWNSLOPE WIND COMPONENT. EXPECT A
PERIOD OF IMPROVEMENT TOWARD SUNRISE AS A TRAILING SFC HI PRES
RDG/AXIS OF DRIER AIR FOLLOWING THE TROF SHIFTS OVHD. BUT THE LULL
WL BE ONLY TEMPORARY WITH A SECOND LO PRES TROF FOLLOWING THRU AT
MID MRNG. THIS DEEPER TROF WL BE FOLLOWED BY STRONGER W WINDS THAT
WL CAUSE GUSTS AS HI AS 30 KT OVER THE EXPOSED KEWEENAW/CMX. THE
COMBINATION OF FALLING LK EFFECT SN AND BLSN WHIPPED UP BY THESE
STRONG WINDS WL LIKELY LEAD TO LIFR CONDITIONS AT THAT SITE. THE DRY
NATURE OF THE ARCTIC AIRMASSES WL LIMIT DETERIORATION AT IWD AND
ESPECIALLY SAW...WHERE THE PREVAILING WLY WIND COMPONENT WL
DOWNSLOPE/DRY AND RESULT IN PREDOMINANT VFR CONDITIONS.
&&

.MARINE /FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE/...

WINDS MAINLY OUT OF A WESTERLY DIRECTION OVER 20KTS WILL PREVAIL
THROUGH MUCH OF THE PERIOD. THE WINDS/WAVES ALONG WITH PLENTY OF
COLD AIR WILL RESULT IN THE POTENTIAL FOR FREEZING SPRAY TONIGHT
INTO FRIDAY. WESTERLY GALES ARE EXPECTED TO RETURN AROUND SUNRISE
THURSDAY BEHIND AN ARCTIC FRONT OVER THE WEST HALF...BEFORE
EXTENDING THROUGH CENTRAL AND EASTERN LS THROUGH EARLY THURSDAY
EVENING.

EXPECT STRONG HIGH PRESSURE ACROSS SW CANADA TO WEAKEN ACROSS THE
PLAINS STATES FRIDAY...WHILE EXTENDING A RIDGE ACROSS LS BY FRIDAY
NIGHT. LOW PRESSURE OVER MANITOBA SATURDAY MORNING WILL SLIDE ACROSS
ONTARIO SATURDAY AFTERNOON AND EVENING...WHILE DRAGGING A TROUGH
OVER LS. A PERIOD OF SW GALES IS POSSIBLE SATURDAY AHEAD OF THE LOW.
ANOTHER LOW PRESSURE SYSTEM...OVER THE DAKOTAS SUNDAY MORNING...WILL
LIKELY FILTER ACROSS LAKE SUPERIOR SUNDAY NIGHT.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST FRIDAY FOR MIZ002-003.

LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST FRIDAY FOR MIZ001-084.

LAKE SUPERIOR...
GALE WARNING FROM 7 AM THIS MORNING TO 1 AM EST FRIDAY FOR
LSZ263>267.

LAKE MICHIGAN...
NONE.
&&

SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...KC
MARINE...JLB

AREA FORECAST DISCUSSION...UPDATED

NWS ST LOUIS MO

812 PM CST FRI DEC 9 2011

.UPDATE...
/812 PM CST FRI DEC 9 2011/

AREA OF CLOUDS ARE MOVING SOUTHEAST INTO CENTRAL MO...SO HAVE
INCREASED CLOUD COVER OVER CENTRAL MISSOURI THIS EVENING. LAST
SEVERAL RUNS OF THE RUC HAVE BEEN CONSISTENT THAT 900-850MB
RELATIVE HUMIDITY WILL REMAIN HIGH ALONG I-70 TOWARD THE ST. LOUIS
METRO AREA INTO EARLY SATURDAY MORNING. SO HAVE GONE WITH MOSTLY
CLOUDY SKIES OVER THE SOUTHWESTERN PART OF THE CWA THROUGH 12Z.
HAVE KEPT LOW TEMPS THE SAME FOR NOW AS TEMPERATURES HAVE FALLEN
QUICKLY UNDER CLEAR SKIES THIS EVENING AND WEAK LOW LEVEL COLD AIR
ADVECTION SHOULD CONTINUE THROUGH MIDNIGHT.

BRITT

.DISCUSSION...
/259 PM CST FRI DEC 9 2011/

NOT A LOT GOING ON IN THE SHORT TERM...JUST DEALING WITH
TEMPS...BEYOND THAT MODELS CONTINUE TO BRING IN A DECENT SYSTEM BY
MIDWEEK NEXT WEEK.

FOR TONIGHT...AS RIDGE OF HIGH PRESSURE SETTLES INTO THE AREA...WILL
SEE CLOUDS CLEAR OUT AND WINDS REMAINING LIGHT AND FROM THE NORTH.
IT WILL BE THE COLDEST NIGHT SO FAR WITH LOWS NEAR 10 DEGREES FAR
NORTH TO THE UPPER TEENS FAR SOUTH AND EAST.

ON SATURDAY...RIDGE OF HIGH PRESSURE TO SLOWLY MOVE OFF TO THE EAST
ALLOWING SOUTHERLY WINDS TO RETURN. CAN EXPECT A WARMUP OVER THE
WEEKEND AND INTO EARLY NEXT WEEK. HIGHS ON SATURDAY WILL REMAIN
RATHER CHILLY...IN THE 30S...THEN TEMPS TO WARM UP INTO THE 40S ON
SUNDAY AND MONDAY. ONE FLY IN OINTMENT WILL BE A WEAK FRONTAL
BOUNDARY THAT WILL APPROACH AREA MONDAY NIGHT AND TUESDAY. WILL
MAINLY JUST SEE AN INCREASE IN CLOUD COVER WITH SYSTEM AS IT STALLS
OUT OVER FORECAST AREA. DEPENDING ON WHERE THE FRONT STALLS
OUT...TEMPS COULD VARY QUITE A BIT ON TUESDAY. FOR NOW HAVE HIGHS IN
THE LOW TO MID 40S.

TUESDAY NIGHT MODELS HAVE FRONTAL BOUNDARY MOVING BACK NORTH AS WARM
FRONT...SO WILL SEE COLDEST TEMPS EARLY ON...THEN TEMPS TO REMAIN
STEADY OR SLOWLY RISE OVERNIGHT. LOW LEVEL MOISTURE WILL BE ON THE
INCREASE AS WELL...SO WILL SEE SOME SHOWERS DEVELOPING...MAINLY OVER
CENTRAL AND SOUTHERN MO.

BEYOND THAT...STRENGTHENING WEATHER SYSTEM OVER THE TEXAS
PANHANDLE...SLIDING NORTHEAST ALONG FRONTAL BOUNDARY INTO THE
FORECAST AREA BY WEDNESDAY NIGHT. SHOULD SEE DECENT CHANCES OF PCPN
IN THE FORECAST AREA WEDNESDAY THROUGH THURSDAY. SOME LOW TO
MODERATE INSTABILITY WITH THIS SYSTEM...SO COULD SEE SOME
THUNDERSTORMS WEDNESDAY AFTERNOON AND NIGHT. AS FOR TEMPS...RATHER
MILD MIDWEEK WITH HIGHS IN THE MID 40S TO LOW 50S WEDNESDAY AND IN
THE UPPER 40S TO MID 50S ON THURSDAY. AS SYSTEM EXITS LATE ON
THURSDAY...COLDER AIR TO SLOWLY FILTER IN WITH HIGHS IN THE UPPER
30S TO UPPER 40S ON FRIDAY.

BYRD

.AVIATION...
/545 PM CST FRI DEC 9 2011/
EXPECTING THAT THE AREA SHOULD REMAIN VFR TONIGHT...WITH JUST A
BKN-OVC045+ DECK OVER CENTRAL MISSOURI FOR A FEW HOURS TONIGHT TO
WATCH. THERE ARE SOME INDICATIONS IN MODEL GUIDANCE THAT MVFR CIGS
AROUND 2000FT CURRENTLY OVER SOUTHERN IOWA COULD SPREAD FURTHER
SOUTHEAST INTO NORTHERN AND EVEN CENTRAL MISSOURI. HOWEVER
CONFIDENCE IN THIS HAPPENING IS LOW AT THIS TIME...SO HAVE LEFT
MENTION OF LOWER CIGS OUT OF THE TAFS FOR NOW. WIND WILL BECOME
WEST-SOUTHWESTERLY OM SATURDAY AS THE SURFACE HIGH DRIFTS EAST OF
THE MISSISSIPPI RIVER. VFR FLIGHT CONDITIONS WILL CONTINUE TO
PREVAIL.

SPECIFICS FOR KSTL...
VFR FLIGHT CONDITIONS AND LIGHT NORTHWEST WIND WILL PREVAIL AT
LAMBERT TONIGHT. THERE IS SOME HINT IN MODEL GUIDANCE THAT CIGS
AROUND 2000FT COULD MOVE IN FROM THE NORTHWEST LATER TONIGHT...BUT
THE SIGNAL IS NOT VERY STRONG AT THIS TIME SO HAVE NOT MENTIONED
IT IN THE 00Z TAF. WIND WILL BECOME SOUTHWESTERLY ON SATURDAY AS
HIGH PRESSURE MOVES EAST OF THE TERMINAL AND VFR CONDITIONS WILL
CONTINUE TO PREVAIL.

CARNEY

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&

WFO LSX

AREA FORECAST DISCUSSION

NWS GLASGOW MT

249 PM MST THU DEC 8 2011

.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH SATURDAY...

WATER VAPOR IMAGERY AND 500 MB HEIGHT FIELD SHOWING THE VERY
STRONG AND CLOSED UPPER LOW CENTER OVER HUDSON BAY AND ITS
ASSOCIATED LARGE SCALE UPPER TROUGH SPREADING OVER A LARGE
PORTION OF THE NORTH AMERICAN CONTINENT. JUST RECENTLY THIS
AFTERNOON THE BASE OF THE STRONGER PORTION OF THE LARGE TROUGH HAS
TAKEN ON A STRANGE SQUARISH SHAPE. VERY SLIGHT LARGE SCALE
TROUGHING IS ALSO PRESENT IN THE SOUTHERN STREAM ACROSS THE
SOUTHERN U.S. STATES. AN UPPER LEVEL RIDGE AND ITS ASSOCIATED
AREA OF HIGH PRESSURE IS GAINING STRENGTH JUST OF THE PACIFIC
NORTHWEST COAST.

LOCALLY...CLOUDS QUICKLY FORMED OVER THE CWA TODAY RIGHT ALONG THE
SURFACE RIDGE AXIS WITH CLEARER SKIES OFF TO THE NORTHEAST AND
CLOUDY SKIES CENTRAL AND SOUTHWEST. ENOUGH ASCENT IS PRESENT TO
SET OFF SOME VERY LIGHT VIRGA AND MAYBE SOME FLURRIES AS IS
EVIDENCED BY THE LIGHT RADAR REFLECTIVITIES TODAY. THE HRRR MODEL
HAS BEEN VERY ACCURATE IN DEPICTING THIS ACTIVITY WHEREAS THE
OTHER OPERATIONAL MODEL SOLUTIONS DID NOT BOTHER MUCH WITH IT.
TRIED TO FOLLOW THE TREND OF THIS HRRR MODEL FOR THE VERY NEAR
SHORT TERM THROUGH TONIGHT AS FLURRIES SHIFT SOUTHWEST AND
DIMINISH SOUTHWARD. ALSO...TONIGHT...WIND CHILL VALUES WILL
APPROACH 20 BELOW ZERO AGAIN ESPECIALLY OVER OUR FAR NORTHEAST
ZONES. BUT WITH WINDS FORECASTED BELOW 10 MPH...FELT IT WAS
SUFFICIENT TO ONLY MENTION IT IN THE HWO.

BEGINNING FRIDAY...THE ARCTIC AIR MASS AND HUDSON BAY LOW QUICKLY
GIVE WAY TO THE APPROACHING HIGH PRESSURE AND WARMER TEMPERATURES
FROM THE WEST. HIGHS SHOULD REBOUND EASILY INTO THE MID 20S
CENTRAL AND WELL ABOVE FREEZING OVER OUR SOUTHWESTERN ZONES.
ANOTHER PERIOD OF CLOUDINESS WILL SWEEP OVER NORTHEAST MONTANA ON
FRIDAY BUT I EXPECT ANY PRECIPITATION TO REMAIN WELL NORTH OF THE
INTERNATIONAL BOARDER. TRIED TO SHOW THE TREND WITH SOME SILENT
POPS AND SKY COVER.

SATURDAY...THE UPPER RIDGE FLATTENS SOMEWHAT BUT STILL MANAGES TO
MAKE SIGNIFICANT INROADS INTO OUR AREA...BRINGING TEMPERATURES
ABOVE FREEZING TO ALL OF NORTHEAST MONTANA EXCEPT THE FAR NORTHEAST
LITTLE CORNER. MOSTLY CLEAR SKIES AND NO PRECIPITATION TO START
THE WEEKEND. BMICKELSON

.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...
MADE SOME INCREASES WITH POPS FOR SUNDAY NIGHT AND ESPECIALLY
MONDAY. A SYSTEM LOOKS STRONGER WITH SOME OF THE MODELS AND
CONSISTENT ON THE ECMWF. ALSO RAISED POPS SLIGHTLY NEAR THE END OF
THE PERIOD CLOSER TO CLIMATOLOGY WITH AN UPPER TROUGH IN THE
WESTERN STATES. REST OF FORECAST LOOKED GOOD. JAMBA

PREVIOUS DISCUSSION...
THE EXTENDED PERIOD FEATURES A SERIES OF SHORTWAVE TROUGHS AND
RIDGES IN A PROGRESSIVE PATTERN. LIMITED MOISTURE WITH EACH OF THE
WEATHER SYSTEMS WILL LIMIT PRECIP CHANCES. TEMPERATURES WILL BE
WITHIN 10 DEGREES OF NORMAL DURING THE WHOLE PERIOD.

AN UPPER RIDGE MOVES TO THE EAST SATURDAY NIGHT AND SUNDAY WITH AN
UPPER TROUGH MOVING THROUGH EASTERN MONTANA ON MONDAY. THIS WILL
BRING A DRY COLD FRONT ACROSS THE AREA ON SUNDAY. LOOK FOR
SOMEWHAT COLDER AIR SUNDAY NIGHT AND MONDAY.

SHORTWAVE RIDGE FOLLOWS ON TUESDAY. ECMWF CURRENTLY WARMER THAN
THE GFS WITH THE TEMPERATURES. WILL FORECAST ON THE COLDER SIDE OF
THE POSSIBILITIES FOR NOW GIVEN THAT LIGHT WINDS SHOULD LEAD TO
POOR MIXING WITH LOW LEVEL INVERSIONS TRAPPING COLD AIR AT THE
SURFACE.

ANOTHER SHORTWAVE TROUGH MOVES THROUGH THE AREA WEDNESDAY AND THURSDAY
WITH ANOTHER DRY COLD FRONT AND SOMEWHAT COLDER AIR. FORRESTER

.AVIATION...
CLOUDS AND ANY FLURRIES WILL EXIT TO THE SOUTHEAST THIS EVENING. A
WARM FRONT THEN MOVES EAST ACROSS THE AREA FRIDAY BUT LITTLE OR
NO FLURRIES ARE EXPECTED. WINDS ARE TO REMAIN LIGHT THROUGH THE
PERIOD. MVFR CONDITIONS ARE POSSIBLE WITH THE FLURRIES...BUT VFR
IS GENERALLY EXPECTED. JAMBA

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

WEATHER.GOV/GLASGOW

AREA FORECAST DISCUSSION...UPDATED

NWS GLASGOW MT

940 AM MST THU DEC 8 2011

.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH SATURDAY...

UPDATED THE FORECAST TODAY TO TRY TO GET AHEAD OF SOME POSSIBLE
FLURRIES INDICATED BY THE HRRR MODEL FOR THIS AFTERNOON AND
EVENING. SINCE THAT MODEL WAS THE ONLY CORRECT MODEL FOR
YESTERDAYS SNOWFALL...TRYING TO LEAN A LITTLE MORE IN THAT
DIRECTION. OTHER MODELS INDICATING AN INCREASE IN CLOUDINESS AS
WELL...SO I BUMPED UP POPS A BIT AND PUT IN SOME FLURRIES FOR THE
IMMEDIATE SHORT TERM. BMICKELSON

PREVIOUS SHORT TERM DISCUSSION...MASSIVE HUDSON BAY LOW PRESSURE
SYSTEM RESULTING IN A STRONG NW FLOW ALOFT WITH STEADY COLD
ADVECTION FOR NE MT. THIS MORNINGS LOWS RUNNING 20F COLDER THAN
YESTERDAY...AND HIGHS WILL BE AROUND 15F COLDER THAN
YESTERDAY...AS THE COLD AIR ADVECTION ENDS THIS AFTERNOON. THIS
ASSOCIATED WITH A POLAR SURFACE HIGH FROM NW CANADA THAT CALVED
OFF MOVING SE ACROSS THE ROCKIES YESTERDAY...ONE CENTER NOW OVER
SE AB/NC MT. THIS CENTER WILL BE OVER E MT THIS AFTERNOON AND
EVENING.

SATELLITE PICTURES SHOW A BAND OF MID-LEVEL OVERCAST ALIGNED
ALONG THE STRONG NW JET IN A SLIGHTLY CYCLONIC FLOW. THIS COVERS
ROUGHLY SW THIRD OF OUR CWA...NOT MOVING MUCH...BUT IT IS SHALLOW
AND SHOULD GRADUALLY BREAK UP AS THE DAY GOES ON. REST OF FORECAST
AREA IS CLEAR.

CLOSED UPPER HIGH ALONG PACIFIC COAST MOVES ACROSS THE INLAND WEST
AND WEAKENS FRI/SAT. THIS BRINGS MUCH WARMER AIR ALOFT TO OUR AREA
FRIDAY. SURFACE PRESSURE GRADIENTS ARE WEAK AND FORECAST SOUNDINGS
SHOW SURFACE-BASED INVERSION REMAINING ALL DAY. ALTHOUGH NOT
GREAT...THERE WILL ALSO BE A SIGNIFICANT SNOW COVER EFFECT AND MOST
OF THE CWA HAS AN INCH OR TWO ON GROUND. THE OTHER NEGATIVE FOR
FRIDAY IS THERE WILL BE MOSTLY CLOUDY SKIES HOLDING THE COLDER AIR
IN MORE. THIS IS WARM ADVECTION MID/HIGH CLOUDS...AND WE WILL BE ON
THE COLD SIDE OF THE RIDGE TOO. MOS LOOKS REASONABLE...BUT WILL GO ON
THE COLD SIDE FOR THE LOWER MILK/LOWER MISSOURI RIVER VALLEYS.

FURTHER WARMING ALOFT FOR SAT...THICKNESSES WELL INTO THE 540S
DM. 850 MB TEMPS CLIMB TO AS HIGH AS 7C. WEAK PRESSURE PATTERN
SIMILAR TO FRI THOUGH. HOWEVER SAT SHOULD HAVE FULL SUNSHINE
EFFECT AND THE RIDGE WILL WEAKEN TO A MODERATE WESTERLY FLOW
FAVORING SIGNIFICANT SHALLOWING OUT AND MODIFICATION OF THE
COLDER AIR. STILL THE LOWER MILK/LOWER MISSOURI RIVER VALLEYS WILL
LAG BEHIND IN THE WARMER TEMPS. SIMONSEN

.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...
THE EXTENDED PERIOD FEATURES A SERIES OF SHORTWAVE TROUGHS AND
RIDGES IN A PROGRESSIVE PATTERN. LIMITED MOISTURE WITH EACH OF THE
WEATHER SYSTEMS WILL LIMIT PRECIP CHANCES. TEMPERATURES WILL BE
WITHIN 10 DEGREES OF NORMAL DURING THE WHOLE PERIOD.

ANOTHER SHORTWAVE TROUGH MOVES THROUGH THE AREA WEDNESDAY AND THURSDAY
WITH ANOTHER DRY COLD FRONT AND SOMEWHAT COLDER AIR. FORRESTER

.AVIATION...
CLOUDS ARE EXPECTED TO INCREASE OVER THE TAF SITES TODAY. FLURRIES
CAN BE EXPECTED IN THE AREA THIS AFTERNOON IF NOT LOW VFR
CLOUDINESS. VISIBILITIES COULD BRIEFLY DROP INTO MVFR CATEGORY.
ANOTHER BAND OF CLOUDINESS WILL MOVE ACROSS THE AREA FRIDAY...AND
BRIEF FLURRIES ARE AGAIN POSSIBLE. JAMBA

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

WEATHER.GOV/GLASGOW

AREA FORECAST DISCUSSION...CORRECTED HYDROLOGY

NWS NORTH PLATTE NE

348 PM CST THU DEC 8 2011

.DISCUSSION...
BANDED FOLDS OF THETA E AND EPV CONTINUE TO PRODUCE LIGHT TO
MODERATE SNOW. THE RUC SUGGESTS THIS SNOW SHOULD MOVE OUT OF THE FCST
AREA BY 02-03 UTC THIS EVENING. ANOTHER WEAK WAVE ACROSS ERN MT THIS
AFTN SHOULD SLICE THROUGH NCNTL NEB MAINLY AFTER 06Z TONIGHT THROUGH
15Z FRIDAY. THE NAM...GFS AND GEM SUPPORT THIS SOLN.

WE CONTINUE THE PATCHY FREEZING DRIZZLE ACROSS PARTS OF SCNTL AND
SWRN NEB THIS EVENING. AN ARCTIC FRONT CURRENTLY NEAR KTIF WILL MOVE
SOUTH AND WASHOUT PERHAPS DRYING THE MIDLEVEL ALLOWING FOR LOW LEVEL
SATURATION AND FREEZING DRIZZLE.

BEHIND THE SECOND DISTURBANCE TONIGHT ANOTHER ARCTIC HIGH WILL BUILD
INTO THE UPPER MISSOURI BASIN AND BE CENTERED OVER WRN SD/ND FRIDAY
MORNING. THIS IS A BIG BREAK FOR THE FCST AREA AS LOWS OF -20F
OCCURRED BENEATH ACROSS WRN CANADA THURSDAY MORNING. THIS HIGH IS
FCST TO DRIFT THROUGH THE FCST AREA FRIDAY PRODUCING CLEAR SKIES AND
COLD WEATHER WITH HIGHS ONLY IN THE 20S. BY FRIDAY EVENING...LOW
PRESSURE WILL BE TRACKING CNTL CANADA PRODUCING AS WARM WESTERLY
H850MB FLOW WITH H850 TEMPS RISING TO NEAR 0C BY SATURDAY MORNING.
THUS LOWS SHOULD OCCUR AT OR BEFORE MIDNIGHT MOST AREAS AND THEN
WARM.

FOR SATURDAY...WEST AND SOUTHWEST WINDS CONTINUE WITH HIGHS IN THE
40S. WINDS TAKE A MORE SOUTHERLY TACK SUNDAY AHEAD OF A COLD FRONT
PROGGED TO MOVE THROUGH SUNDAY NIGHT AND MONDAY. STILL HIGHS SUNDAY
SHOULD RISE INTO THE 40S. A COLD FRONT MOVING THROUGH MONDAY IS
EXPECTED TO TAKE THE EDGE OFF HIGHS. 30S APPEAR TO BE THE OPERATIVE
MODE.

THE GEM...GFS AND ECM ARE IN GOOD AGREEMENT ON A SIGNIFICANT SHORT
WAVE TRACKING THROUGH THE CNTL PLAINS WEDNESDAY. TEMPS MIGHT BE WARM
ENOUGH FOR RAIN AS H10-5 THICKNESSES HOVER NEAR 546DAM AND H850MB
TEMPS -3 TO 0C. A CHANCE OF RAIN AND SNOW IS SHOWN EAST WITH SLIGHT
CHANCE OF SNOW WEST. THE GFS AND GEM SHOW EVAPORATIVE COOLING WHILE
THE ECM DOES NOT. THIS SYSTEM SHOULD EXIT WEDNESDAY NIGHT WITH
ANOTHER STRONG COLD FRONT DROPPING TOWARD THE FCST AREA.

.AVIATION...
OR 18Z TAFS...SMALLER SCALE FRONTOGENETIC BAND SLIDING ACROSS THE
SANDHILLS INTO LATE AFTERNOON LOWERING CREATING VSBYS TO 3/4 TO
1/2SM AT TIMES THOUGH LATE AFTERNOON. THIS AREA OF HEAVIER SNOWFALL
LIES BETWEEN THE KLBF AND KVTN TAF SITES...BUT MAY APPROACH THE KLBF
TAF SITE BY 22Z. LATEST NAM AND HRRR SUGGEST THIS WILL SLIDE NORTH
AND EAST OF KLBF HOWEVER AND AS SUCH HAVE NOT LOWERED VSBY AT KLBF
DUE TO THIS FEATURE. THIS TIGHTER...SMALLER SCALE BAND LIKELY A
RESULT OF LINGERING BUT WEAK FRONTOGENESIS IN A REGION OF NEGATIVE
EPV IN THE 700-600MB LAYER. WOULD EXPECT THIS BAND TO DISSIPATE IN
THE NEXT 2 TO 3 HRS AS WEAK INSTABILITY STABILIZES BUT WILL MONITOR.
LARGER SCALE DRIER AIR IS WORKING IN ACROSS THE WESTERN PORTION OF
THE STATE AND RADAR ECHOES ARE DECREASING SOME FROM WEST TO EAST AND
WILL EXPECT THAT TREND TO CONTINUE THROUGH EVENING.

FOR TONIGHT...SECONDARY SHORT WAVE SHOULD BE ENOUGH TO GENERATE
FLURRIES TO -SN ACROSS THE NORTHERN PORTION OF THE STATE...THOUGH
A MORE SHALLOW AREA OF LIFT CLOSER TO THE SURFACE AND FAVORABLE
CROSS-OVER TEMPS SHOULD LEAD TO AT LEAST BR BUT POSSIBLY FZFG
OVERNIGHT FURTHER SOUTH AND NEAR THE KLBF SITE. WILL BE REFINING
THIS PORTION OF THE FORECAST IN THE NEXT FEW HOURS SINCE
CONFIDENCE IN THIS SCENARIO IS LOW AT THE MOMENT. A GENERAL
CLEARING TREND IS EXPECTED BY LATE MORNING FRIDAY.

&&
.HYDROLOGY...
A FLOOD WARNING FOR ICE JAMMING HAS BEEN ISSUED ON THE NORTH
PLATTE RIVER AT LEWELLEN. THE FLOOD WARNING WILL CONTINUE UNTIL
FURTHER NOTICE. WEATHER CONDITIONS FEATURING WARM TEMPS DURING THE
DAYTIME AND SINGLE DIGITS AT NIGHT THIS WEEKEND COULD CAUSE THE
JAMMING TO PERSIST.

$$
SHORT TERM/LONG TERM...CDC
AVIATION...JWS

AREA FORECAST DISCUSSION...UPDATED

NWS NORTH PLATTE NE

312 PM CST THU DEC 8 2011

&&
.HYDROLOGY...
ICE JAMMING HAS DEVELOPED ON THE NORTH PLATTE RIVER BETWEEN LEWELLEN
AND NORTH PLATTE. A FLOOD ADVISORY WILL CONTINUE UNTIL FURTHER
NOTICE. WEATHER CONDITIONS FEATURING WARM TEMPS DURING THE DAYTIME
AND SINGLE DIGITS AT NIGHT THIS WEEKEND COULD CAUSE THE JAMMING TO
PERSIST.

$$
SHORT TERM/LONG TERM...CDC
AVIATION...JWS

AREA FORECAST DISCUSSION

NWS NORTH PLATTE NE

244 PM CST THU DEC 8 2011

$$
SHORT TERM/LONG TERM...CDC
AVIATION...JWS

AREA FORECAST DISCUSSION

NWS CHARLESTON WV

545 AM EST THU DEC 8 2011

.SYNOPSIS...
HIGH PRESSURE THURSDAY. COLD FRONT FRIDAY NIGHT. HIGH PRESSURE
FOR THE WEEKEND.

.NEAR TERM /THROUGH TONIGHT/...
600AM UPDATE...
FORECAST REMAINS LARGELY ON TRACK. UPDATE INSERTED FOR CLOUD DECK
CONTINUING TO LINGER IN THE NORTHERN MOUNTAINS EARLY THIS MORNING.

PREVIOUS DISCUSSION...
CLEARING ACROSS THE LOWLANDS HAS RESULTED IN STRONG RADIATIONAL
COOLING. STILL EXPECTING TEMPS TO CRASH THROUGH EARLY MORNING HOURS.
CLEARING HAS STALLED A BIT IN THE MOUNTAINS WHERE EKN AND BKW STILL
REPORTING BKN CLOUD COVER. EXPECTING THESE SITES TO CLEAR OUT
COMPLETELY BY 10Z.

CURRENT IR SATELLITE IMAGERY SHOWS SHALLOW CLOUD DECK KNOCKING ON
THE DOORSTEPS OF OUR SE OHIO COUNTIES. LATEST RUN OF THE RUC HAS
THIS FEATURE DIAGNOSED WELL WITH COINCIDING 850MB MOISTURE MOVING
ACROSS OUR NORTHERN TIER COUNTIES AND SLOSHING UP AGAINST THE HIGH
TERRAIN OF THE NE MNT COUNTIES. RESULTANT RUC SOUNDINGS DISPLAYED IN
BUFKIT TRYING TO DEVELOP LOW STRATUS AGAINST THE MOUNTAINS AROUND
12Z. NOT COMPLETELY SOLD ON THIS AS RUC 850MB MOISTURE SHOULD ERODE
FURTHER DOWNSTREAM OF THE SOUTHERN GREAT LAKES. ALSO...WARMING TREND
IN 850MB TEMPS SHOULD HELP TO DRY THE COLUMN FURTHER. ALL
TOLD...WILL NOT INCLUDE STRATUS DEVELOPMENT IN THIS PACKAGE...BUT
WILL CONTINUE TO MONITOR FORTHCOMING GUIDANCE AND TRENDS.

A CHANGE OF PACE TODAY...RELATIVE TO THE LAST FEW DAYS. SUNNY SKIES
WITH COLDER TEMPERATURES ARE EXPECTED AS CWA IS NOW UNDER THE
CONTROL OF A SURFACE HIGH.

.SHORT TERM /FRIDAY THROUGH SUNDAY/...
NEXT SYSTEM TO DEAL WITH WILL BE A MOISTURE STARVED COLD FRONT
EXPECTED TO ENTER THE SOUTHEAST OHIO ZONES AFTER 18Z FRIDAY. SREF
PROBABILITIES OF ACCUMULATING PRECIPITATION ARE ON THE LOW
SIDE...BELOW 50 PERCENT...AND WILL HAVE A TOUGH TIME SATURATING
ABOVE ABOUT 750MB. THAT BEING SAID...SNOW SHOWERS ARE POSSIBLE UPON
PASSAGE...LIKELY NOT ACCUMULATING OR GIVING TRACE ACCUMULATIONS.

OF MORE SIGNIFICANCE IS THE AIRMASS BEHIND THE COLD FRONT. 500MB
HEIGHTS DROP IN THE POST FRONTAL TROUGH...AND 850MB TEMPERATURES
ALSO DECREASE INTO THE MINUS TEENS COME SATURDAY. THERMAL TROUGH AT
THIS LEVEL WILL PERSIST OVER THE NORTHEAST MOUNTAINS...AND WITH A
CLEARING SKY...SATURDAY NIGHT TEMPERATURES LOOK VERY COLD. STRONG
HIGH PRESSURE SETTLES IN OVER THE REMAINDER OF THE WEEKEND IN A
LARGELY DRY PATTERN THROUGH EARLY NEXT WEEK.

.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
A BREAK FROM ANY RAIN OR SNOW WILL OCCUR DURING THE FIRST SEVERAL
DAYS OF THIS PERIOD. A POCKET OF COLD AIR WILL BE IN PLACE THANKS TO
SURFACE HIGH PRESSURE. AS THE SURFACE HIGH PRESSURE SLIDES
NORTHEAST...POCKET OF COLDEST TEMPERATURES WILL ALSO FOLLOW. SUNDAY
THROUGH TUESDAY WILL FEATURE MOSTLY SUNNY SKIES DURING THE DAY AND
CLEAR AND COLD AT NIGHT. THE NEXT SYSTEM WILL APPROACH THE AREA
DURING THE MID WEEK. WILL CONTINUE TO MONITOR THE SYSTEM AS IT
DEVELOPS.

GENERALLY FOLLOWED HPC GUIDANCE WITH ONLY A FEW MODIFICATION.

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
MVFR CONDITIONS LINGERING IN CKB AND EKN FOR CIGS WITH RESIDUAL
CLOUD DECK THAT IS RELUCTANT TO ERODE.

CLEAR SKY OVER THE LOWLANDS RESULTING IN VFR...EXPECTING ALL SITES
VFR AFTER 14Z.

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

FORECAST CONFIDENCE: HIGH.

ALTERNATE SCENARIOS: CLOUD DECK OVER CKB AND EKN COULD BECOME MORE
PERSISTENT...LASTING BEYOND 14Z.

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 11 12 13 14 15 16 17 18 19 20 21 22
EST 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
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 M M M M M M H H H H H H
PKB CONSISTENCY H M M H H H H H H H H H
CKB CONSISTENCY M M M M M M H H H H H H

AFTER 12Z FRIDAY...
NO WIDESPREAD IFR EXPECTED.

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

$$
SYNOPSIS...26/TAX
NEAR TERM...TAX
SHORT TERM...26
LONG TERM...JB
AVIATION...TAX

AREA FORECAST DISCUSSION

NWS CHARLESTON WV

355 AM EST THU DEC 8 2011

.SYNOPSIS...
HIGH PRESSURE THURSDAY. COLD FRONT FRIDAY NIGHT. HIGH PRESSURE
FOR THE WEEKEND.

.NEAR TERM /THROUGH TONIGHT/...
CLEARING ACROSS THE LOWLANDS HAS RESULTED IN STRONG RADIATIONAL
COOLING. STILL EXPECTING TEMPS TO CRASH THROUGH EARLY MORNING HOURS.
CLEARING HAS STALLED A BIT IN THE MOUNTAINS WHERE EKN AND BKW STILL
REPORTING BKN CLOUD COVER. EXPECTING THESE SITES TO CLEAR OUT
COMPLETELY BY 10Z.

A CHANGE OF PACE TODAY...RELATIVE TO THE LAST FEW DAYS. SUNNY SKIES
WITH COLDER TEMPERATURES ARE EXPECTED AS CWA IS NOW UNDER THE
CONTROL OF A SURFACE HIGH.

GENERALLY FOLLOWED HPC GUIDANCE WITH ONLY A FEW MODIFICATION.

.AVIATION /09Z THURSDAY THROUGH MONDAY/...
CONDITIONS CONTINUE TO IMPROVE EARLY THIS MORNING FROM W TO E.
MVFR IN MOUNTAINS AS CLOUD COVER AND -SN LINGER A FEW HOURS
LONGER.

CLEAR SKY WEST FROM CRW-CKB LINE RESULTING IN VFR...EXPECTING
THIS TREND TO CONTINUE PUSHING EAST BETWEEN 06Z TO 12Z.

CEILING UNLIMITED AND VSBY UNRESTRICTED 12Z TO 18Z.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z FRIDAY...

FORECAST CONFIDENCE: HIGH.

ALTERNATE SCENARIOS: THERE IS A CHANCE THAT SOME STRATUS MAY REFORM
IN WEST VIRGINIA AT 1 TO 2 THSD FT ON EITHER SIDE OF DAWN/12Z
THURSDAY. BUT WITH WIND AND LOWERING DEW POINTS...DID NOT GO WITH
THAT SCENARIO IN THE 00Z TAF FORECASTS.

DATE THU 12/08/11
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EST 1HRLY 03 04 05 06 07 08 09 10 11 12 13 14
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 M M M M H H H H H H H H
EKN CONSISTENCY M M H M M H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H M M H H H H

AFTER 06Z FRIDAY...
NO WIDESPREAD IFR EXPECTED.

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

$$
SYNOPSIS...26/TAX
NEAR TERM...TAX
SHORT TERM...26
LONG TERM...JB
AVIATION...TAX

AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA

NWS SIOUX FALLS SD

1058 PM CST WED DEC 7 2011

.DISCUSSION.../ISSUED AT 758 PM CST/
WENT AHEAD AND INCREASE LOWS ABOUT 5 TO 8 DEGREES IN MOST SPOTS AS
CLOUD COVER NOW SEEMS TO BE LOCKED IN FOR THE NIGHT...ESPECIALLY
WITH THE APPROACH OF THE UPPER LEVEL WAVE IN THE NORTHERN ROCKIES.
SO...BASICALLY LOOKING AT TEMPERATURES RANGING FROM AROUND THE MID
TEENS TO LOWER 20S. DID ADD SOME FLURRIES AND A SLIGHT CHANCE FOR
LIGHT SNOW IN THE FAR SOUTHERN CWA FRO 9-12Z AS THE RUC AND HRRR
CONTINUE TO INDICATE THAT SOME SNOWFALL MAY GET SQUEEZED OUT OF THE
MID LEVEL DECK MOVING SOUTHWARD. THIS DOES NOT SEEM COMPLETELY OUT
OF THE QUESTION SINCE THE THERMAL PROFILE BECOMES MORE DENDRITIC IN
THE STRONGER FORCING AT THIS TIME AND OUR LOWEST LEVELS ARE NOT
COMPLETELY DRY SO COULD SEE SOME FLAKES WITH THE BETTER CHANCES NEAR
THE MISSOURI RIVER FROM ABOUT 9Z THROUGH 15Z. /08

.AVIATION.../FOR THE 06Z TAF ISSUANCE/
GENERAL VFR CONDITIONS EXPECTED THROUGH 06Z FRI. VERY SMALL THREAT
FOR MARGINAL MVFR STRATUS LATE TONIGHT AND EARLY MORNING BEHIND
COLD FRONT...BUT BELOW MENTIONABLE THRESHOLD...AT WHICH TIME A FEW
FLURRIES AT BEST FOR KSUX AREA...WHICH SHOULD NOT BREACH INTO MVFR
VISIBILITIES. /CHAPMAN

.PREV DISCUSSION.../ISSUED AT 252 PM CST/
FRONTAL BOUNDARY CONTINUES TO DROP SOUTHWARD ACROSS THE REGION THIS
AFTERNOON...AND WILL EXIT THE AREA BY THIS EVENING. MAIN CHALLENGE
TONIGHT WILL BE IN TEMPERATURES...WITH STRONG COLD AIR ADVECTION
BEHIND THE FRONT...MUTED BY CLOUD COVER EXPECTED TO BE OVER MUCH OF
THE AREA DURING THE OVERNIGHT HOURS. WITH BREAKS IN THE
CLOUDS...WILL SEE TEMPERATURES FLUCTUATE DEPENDING ON THE CLOUD
COVER...THOUGH WILL SEE A GENERAL DOWNWARD TREND THROUGH THE NIGHT
WITH LOWS JUST UNDER 10 THROUGH THE HURON TO BROOKINGS CORRIDOR...TO
THE MID TEENS ALONG THE MISSOURI RIVER CORRIDOR WHERE CLOUDS WILL BE
MORE DOMINANT.

MODELS CONTINUING SLIGHT SOUTHWARD TREND WITH PRECIP CHANCES ON
THURSDAY...AS NORTHERN STREAM WAVE DROPS SOUTHEAST INTO THE NORTHERN
PLAINS. 700MB FRONTOGENESIS STILL HUGS THE MISSOURI RIVER VALLEY...
HOWEVER MOST MODELS SHOWING A DRY LAYER IN THE ATMOSPHERE NORTH OF
THE RIVER THAT WILL LIMIT NORTHWARD EXTENT OF ACCUMULATING PRECIP.
HAVE SCALED POPS BACK TO JUST OUR FAR SOUTHERN AREAS...GENERALLY
SOUTH OF LAKE ANDES/KYKN/KSLB LINE...WITH JUST A FEW TENTHS OF SNOW
AT BEST IN THESE AREAS. 850MB BAROCLINIC ZONE LINGERS FROM NORTH
CENTRAL NEBRASKA INTO SOUTHWEST SOUTH DAKOTA INTO THE EVENING AS THE
MAIN WAVE DROPS THROUGH THE DAKOTAS....AND THIS COULD KEEP SOME
LIGHT SNOW OR FLURRIES GOING JUST TO OUR SOUTHWEST INTO THURSDAY
EVENING. WILL KEEP IT DRY IN OUR AREA...THOUGH SOME MID CLOUDS WILL
LIKELY HANG AROUND IN THE WESTERN PORTIONS OF THE MISSOURI RIVER
VALLEY THROUGH 06Z BEFORE DRIER MID LEVEL AIR PUSHES SOUTH WITH THE
WAVE.

FOCUS FOR THE REMAINDER OF THE WEEK AND INTO THE WEEKEND WILL BE ON
TEMPERATURES...WITH POTENTIAL FOR SOME DECENT RADIATIONAL NIGHTTIME
COOLING. SURFACE RIDGE AXIS SHIFTS INTO NEBRASKA SO WILL LIKELY NOT
SEE WINDS GO COMPLETELY CALM EXCEPT IN MORE SHELTERED AREAS. HOWEVER
EVEN WITH RELATIVELY LIGHT WEST-SOUTHWEST WINDS EXPECTED OVER THE
SNOWPACK AREAS...SHOULD SEE QUICK EVENING DROPS IN TEMPERATURES
ACROSS OUR SOUTHEAST THURSDAY AND FRIDAY NIGHTS...WITH NON-DIURNAL
RISE IN TEMPERATURES EXPECTED LATER FRIDAY NIGHT AS WINDS/CLOUDS
INCREASE AHEAD OF WARM FRONT. DAYTIME TEMPERATURES SHOULD SEE
GRADUAL DECREASE IN EFFECT OF SNOWPACK ON READINGS...THOUGH COULD
STILL HOLD HIGHS BACK A FEW DEGREES ON FRIDAY WITH FULL SUNSHINE AND
LIMITED MIXING.

LONGER RANGE STILL LOOKS RELATIVELY DRY THROUGH TUESDAY...WITH
MODELS SHOWING DECENT AGREEMENT DIGGING YET ANOTHER WAVE INTO THE
SOUTHWEST CONUS WHILE SEPARATE NORTHERN STREAM TROUGH SLIDES EAST
ACROSS THE CANADIAN BORDER. WEAK WAVE SEEN EJECTING OUT OF SOUTHWEST
SYSTEM INTO THE MIDDLE MISSOURI VALLEY ON MONDAY. FORECAST SOUNDINGS
QUITE SPARSE ON MOISTURE ABOVE 850MB...BUT SIMILAR IN SHOWING STRONG
NORTHWARD PUSH OF LOW LEVEL MOISTURE/STRATUS AHEAD OF COLD FRONT IN
THE LATE NIGHT/MORNING HOURS. MOISTURE PROFILES FROM ALL MODELS ARE
REMINISCENT OF DRIZZLE SOUNDINGS...WITH LACK OF MOISTURE IN CRITICAL
ICE-BEARING LAYER ALOFT...BUT TOUGH TO PINPOINT THREAT OF POTENTIAL
FREEZING PRECIP AT DAY 4-5 RANGE SO WILL JUST GO WITH MENTION OF
LIGHT RAIN/SNOW WITH SLIGHT CHANCE POPS IN OUR FAR SOUTHEAST DURING
THE DAY MONDAY.

GREATER DIFFERENCES IN THE MODELS ARISE BY THE MIDDLE OF NEXT WEEK
IN HANDLING OF NORTHERN STREAM TROUGH AS IT MOVES ACROSS THE GREAT
LAKES AND EASTERN CANADA...AS WELL AS SOUTHWEST CONUS CUTOFF. GFS
STRONGER/SLOWER WITH NORTHERN STREAM TROUGH WHILE ALSO MAINTAINING
STRONGER SOUTHWEST SYSTEM...WITH ANOTHER RELATIVELY WEAK WAVE
LIFTING NORTHEAST THROUGH THE PLAINS MIDWEEK. ECMWF ON THE OTHER
HAND IS SLIGHTLY WEAKER/FASTER WITH THE NORTHERN STREAM TROUGH...
ALLOWING STRONGER CHUNK OF ENERGY TO LIFT NORTHEAST INTO THE PLAINS
ON WEDNESDAY. EITHER SCENARIO GIVES AT LEAST SOUTHERN PARTS OF OUR
AREA A CHANCE OF PRECIP LATE IN THE FORECAST PERIOD. MAIN DIFFERENCE
IS STRONGER ECMWF SPREADS THE PRECIP MUCH FARTHER NORTHEAST THAN THE
GFS. IN EITHER CASE...SEEMS SOME CHANCE POPS ARE WARRANTED FOR THE
DAY 7 TIMEFRAME AT THIS TIME. AFOREMENTIONED DIFFERENCES ALSO RESULT
IN DRASTICALLY DIFFERENT LOW LEVEL TEMPERATURE PROFILES...WITH ECMWF
PULLING WARMER AIR MUCH FARTHER NORTH THAN GFS WHERE NORTHERN STREAM
REMAINS DOMINANT. WITH RIDE WITH BLEND OF THE TWO SOLUTIONS AND KEEP
PRECIP TYPE AS ALL SNOW FOR NOW...BUT WARMER ECMWF COULD BRING A
THREAT OF LIQUID PRECIP INTO THE MIX AND WILL KEEP A CLOSE EYE ON
TRENDS FOR THIS OVER THE NEXT FEW DAYS.

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
NE...NONE.
IA...NONE.

AREA FORECAST DISCUSSION

NWS LUBBOCK TX

149 PM CST THU DEC 8 2011

.UPDATE...
UPDATED FOR WARMER TEMPERATURES AGAIN THIS AFTERNOON...CLOSE TO
LATEST RUC SOLUTION WHICH SEEMS TO BE STRUGGLING LESS WITH THE
THINNING SNOW COVERAGE THAN EITHER THE WRF/NAM OR GFS. FRONT STILL
EXPECTED TO DROP SOUTHWARD THIS EVENING. RMCQUEEN

.AVIATION...
PRE-FRONTAL VFR CONDITIONS WITH DOWNSLOPE BREEZES. COLD FRONT WILL
EDGE SOUTHWARD THIS EVENING...CLOSE TO PREVIOUS TIMING. WE ARE
LEANING MORE TOWARDS AREAS OF SURFACE SATURATION DEVELOPING LATER
TONIGHT...POSSIBLE FOG...WHILE THE GFS STILL FAVORS LIFTING THIS
INTO A LOW STRATUS DECK NEAR OR SHORTLY AFTER SUNRISE FRIDAY. WE
WILL RETAIN TEMPO GROUPS FOR NEAR-IFR STRATUS LAYER STARTING
BEFORE DAYBREAK FRIDAY. RMCQUEEN

.PREV DISCUSSION... /ISSUED 555 AM CST THU DEC 8 2011/

AVIATION...
VFR CONDITIONS WILL PERSIST AT BOTH KLBB AND KCDS THROUGH AT LEAST
09/00Z. CONFIDENCE THEN DECREASES AS MODELS SHOW A MOISTENING LOW
LEVEL ATMOSPHERE IN THE WAKE OF A COLD FRONT. CURRENT INDICATIONS
SUGGEST THAT IFR CIG RESTRICTIONS COULD OCCUR DURING THE 06-12Z
TIME-FRAME. FOG MAY BE AN OUTSIDE POSSIBILITY...BUT CONFIDENCE IN
THIS IS LOW GIVEN CONTINUED NORTH/NORTHWESTERLY WINDS WHICH MAY
HELP LIMIT SURFACE FOG POTENTIAL.

PREV DISCUSSION... /ISSUED 406 AM CST THU DEC 8 2011/

SHORT TERM...
TODAY/S FORECAST IS COMPLICATED BY AN ANTICIPATED FRONTAL PASSAGE.

THE CURRENTLY DIFFUSE FRONTAL BOUNDARY OVER THE CENTRAL PLAINS WILL
MAKE AN ACCELERATED PUSH SOUTHWARD TODAY IN THE WAKE OF A SHARPENING
SHORTWAVE TROUGH OVER THE NORTHERN PLAINS/UPPER MIDWEST. MODELS SHOW
THIS FRONT ENTERING THE EXTREME SOUTHWESTERN PANHANDLE BY LATE
AFTERNOON...THEN CLEARING THE FORECAST AREA BY 06-09Z.

TIMING OF THE FRONT AND PROSPECTS FOR AT LEAST SOME MID/HIGH CLOUDS
ASSOCIATED WITH A SUBTLE SHORTWAVE TROUGH SEEN IN VAPOR IMAGERY OVER
NEW MEXICO WILL MAKE FOR PROBLEMATIC AFTERNOON TEMPERATURE
FORECASTS. AS WAS THE CASE YESTERDAY...MOS VALUES APPEAR LOW GIVEN
PROGGED LOW LEVEL THERMAL PROFILES AND THICKNESSES. THUS HAVE EDGED
FORECAST TEMPERATURE MAXIMA UP 5+ DEGREES RELATIVE TO GUIDANCE.

FORECAST PROFILES SHOW CONSIDERABLE POST FRONTAL MOISTENING OF THE
LOWER TROPOSPHERE BY LATE EVENING/OVERNIGHT. GIVEN PERSISTENT
NORTH/NORTHWESTERLY DOWNSLOPE WINDS NEAR 10 KT WILL FAVOR AN
INCREASING STRATUS DECK VERSUS FOG ATTM.

LONG TERM...
NEAR ZONAL FLOW ALOFT WILL ENSUE LATE THURSDAY THROUGH FRIDAY...AS
AN UA DISTURBANCE ACROSS THE CENTRAL/HIGH PLAINS DIVES A COLD FRONT
ACROSS THE SOUTHERN PLAINS TODAY. ALTHOUGH UPPER LEVEL ATMOSPHERIC
LEVELS APPEAR RATHER DRY /PWATS BELOW 0.40 INCHES/...POST FRONTAL
LOW LEVEL MOISTENING IS EXHIBITED FRIDAY MORNING...WITH HINTS OF
POTENTIAL FOG. HOWEVER..NORTHERLY WIND SPEEDS AOA 10 KTS MAY AID
TO MITIGATE THE PRODUCTION OF FOG AND WILL NOT ADD A MENTION WITH
THIS FORECAST PACKAGE ATTM. THUS CURRENT THINKING IS THAT COOL
TEMPS /30S AND 40S / AND INCREASING LOW LEVEL CLOUDINESS WILL BE
THE RULE. SFC RIDGE WILL TRANSLATE NE OF THE REGION ON
SATURDAY...AND PROMOTE SFC WINDS TO VEER TO A MORE SOUTH TO
SOUTHEASTERLY/UPSLOPE WIND COMPONENT...WHICH MAY ENSUE THROUGH
MONDAY MORNING. TEMPS WILL WARM INTO THE 40S AND 50S ON SUNDAY AND
MONDAY AS SHORTWAVE RIDGING PASSES OVERHEAD...AND SLIGHTLY BREEZY
SOUTHERLY SFC WINDS OCCURS DURING THE AFTERNOON HOURS.
FURTHERMORE....BOTH THE GFS AND ECMWF HINT AT THE NORTHWARD
TRANSPORT OF LOW LEVEL MOISTURE AND LIGHT QPF VALUES ESPECIALLY
ACROSS ERN ZONES THROUGH THE AFOREMENTIONED PERIOD.
CONCURRENTLY...THE EVOLUTION OF FLOW ALOFT FROM NEAR ZONAL TO SW
FLOW WILL TAKE PLACE...AS A PACIFIC UA LOW COMMENCE TO MOVE ESE
ACROSS CALIFORNIA. THEREAFTER...MODELS STILL STRUGGLE WITH HOW
THIS UA DISTURBANCE WILL EVOLVE.

IF FOLLOWING THE GFS /WHICH HAS SHOWN INCONSISTENCY FROM RUN TO RUN
THE LAST FEW DAYS/ QUICKLY PROPAGATES THE PACIFIC UA DISTURBANCE
ACROSS THE DESERT SW ON TUESDAY AND ACROSS THE CWA ON WEDNESDAY. A
BREEZY NORTHWESTERLY PACIFIC FRONT WILL MOVE ACROSS THE REGION
WEDNESDAY WITH A DECLINE IN PRECIP FROM WEST TO EAST. THE SYSTEM
WILL BE EAST OF THE CWA BY THURSDAY. PRECIP TYPE APPEARS TO BE ALL
LIQUID AS 850 MB TEMPS REMAIN ABOVE 0 DEGREES CELSIUS. HOWEVER THE
GFS COULD BE OVER DOING THE WARMTH ALOFT AND WITHIN THE BL. THE ECMWF
SOLUTION ON THE OTHER-HAND IS A BIT STRONGER WITH THE UA LOW AS IT
SLOWLY TRANSLATES IT TO ACROSS THE DESERT SW WEDNESDAY
MORNING...BEFORE EJECTING NE TO ACROSS THE CENTRAL PLAINS WEDNESDAY
NIGHT. BREEZY WESTERLY WINDS WILL ENSUE AS THE SYSTEM BRUSHES THE
CWA. AN ALL LIQUID PRECIP TYPE IS ALSO SHOWN BY THE ECMWF. WILL TEND
TO LEAN TOWARDS THE ECMWF AS IT HAS BEEN MOST CONSISTENT.
HOWEVER...HAVE DECIDED TO MAINTAIN SILENT POPS /ALTHOUGH BUMPED POPS
TO 10 PERCENT TUESDAY NIGHT-WEDNESDAY/ ATTM AS THE ANALYSIS OF
FUTURE MODEL RUNS FOR CONSISTENCY IS HIGHLY DESIRED.

.PRELIMINARY POINT TEMPS/POPS...
FRIONA 15 33 20 40 22 / 0 10 0 0 0
TULIA 20 36 22 42 23 / 10 10 0 0 0
PLAINVIEW 21 37 23 43 25 / 0 10 0 0 0
LEVELLAND 19 38 24 43 25 / 0 10 0 0 0
LUBBOCK 21 39 24 44 26 / 0 10 0 0 10
DENVER CITY 21 39 24 43 27 / 0 10 0 0 10
BROWNFIELD 21 39 25 44 27 / 0 10 0 0 10
CHILDRESS 25 38 27 47 28 / 10 10 0 0 0
SPUR 24 38 25 46 27 / 0 10 0 0 10
ASPERMONT 26 41 28 48 30 / 0 10 0 0 10

.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

05/99/05

AREA FORECAST DISCUSSION

NWS PUEBLO CO

1047 PM MST FRI DEC 9 2011

.AVIATION...
WESTWARD EXTENT OF STRATUS AND FOG AGAIN THE CONCERN
OVERNIGHT...ESPECIALLY ACROSS THE LOWER ARKANSAS VALLEY.
PERSISTENT AREA OF STRATUS AND FOG FROM JUST EAST OF KPUB THROUGH
KLHX AND KLAA HAS SHOWN VERY LITTLE WESTWARD MOTION SO
FAR...THOUGH AREAL COVERAGE OF STRATUS HAS EXPANDED SLIGHTLY NEAR
THE KS BORDER. LATEST RUC SUGGESTS FOG/STRATUS AREA WILL REMAIN
RELATIVELY UNCHANGED THROUGH SATURDAY MORNING...WHILE HRRR SNEAKS
A NARROW RIBBON OF FOG WESTWARD ALONG THE ARKANSAS THROUGH PUEBLO
COUNTY AFTER 09Z. THUS FOR THE KPUB TAF...BACKED OFF THE ONSET OF
IFR/LIFR CONDITIONS UNTIL 10Z...THEN KEPT ONLY A BRIEF PERIOD OF
IFR CIGS IN THE 10Z-14Z PERIOD BEFORE IMPROVING TO VFR BY 16Z. AT
KALS...GIVEN LITTLE CHANGE FROM LAST NIGHTS CONDITIONS...SUSPECT
AT LEAST SOME SHALLOW DENSE FOG IS LIKELY NEAR THE TERMINAL BY
SUNRISE...AND THUS KEPT A BRIEF PERIOD OF LIFR HERE FROM 09Z-15Z
BEFORE IMPROVING. KCOS SHOULD STAY OUT OF THE FOG/CLOUDS AND
REMAIN VFR OVERNIGHT INTO SAT MORNING. EXPECT FOG TO LIFT ALL
AREAS BY MIDDAY SAT...WITH VFR CONDITIONS INTO SAT NIGHT.
--PETERSEN

.PREV DISCUSSION... /ISSUED 612 PM MST FRI DEC 9 2011/

UPDATE...
WILL BE UPDATING MOST GRIDS/PRODUCTS TO ADD MENTION OF FOG FOR THE
REST OF THE NIGHT ALONG THE ARKANSAS RIVER FROM PUEBLO
EASTWARD...AS VISIBILITY HAS DROPPED TO AROUND A QUARTER MILE AT
BOTH LAMAR AND LA JUNTA. MAY EVENTUALLY NEED A DENSE FOG ADVISORY
FOR A FEW HOURS...THOUGH WILL WAIT TO SEE HOW FAR WEST FOG/STRATUS
DEVELOPS OVER THE NEXT 1-2 HOURS BEFORE ISSUING ANYTHING. ALSO
ADDED A MENTION OF FOG TO PORTIONS OF THE SAN LUIS VALLEY LATE
TONIGHT...AS ANOTHER ROUND OF DENSE FOG IS POSSIBLE AROUND SUNRISE
ALONG THE RIO GRANDE FROM ALAMOSA SOUTHWARD. --10

PREV DISCUSSION... /ISSUED 313 PM MST FRI DEC 9 2011/

SHORT TERM...
(TONIGHT AND SATURDAY)

SOME LOW CLOUDS HAVE REMAINED OVR THE LOWER ARKANSAS RIVER VALLEY
THRU THE DAY...EAST OF PUEBLO TO THE KANSAS BORDER. AS A
RESULT...TEMPS HAVE BEEN ONLY IN THE 20S.

NW FLOW ALOFT WL REMAIN OVR THE AREA TONIGHT AND SATURDAY...WITH A
WEAK SHORTWAVE TROF MOVING THRU THE AREA ON SATURDAY.

TONIGHT...ALTHOUGH THE AREA OF STRATUS OVR THE SERN PLAINS HAS BEEN
SLOWLY SHRINKING...IT LOOKS LIKE IT WL PROBABLY EXPAND AGAIN AS WE
WL AGAIN SEE AREAS OF STRATUS ACRS PORTIONS OF THE SERN PLAINS ONCE
THE SUN GOES DOWN AND TEMPS COOL. THE SAN LUIS VALLEY SHOULD ALSO
SEE AREAS OF LOW CLOUDS/FOG DEVELOP AGAIN.

TEMPS ALOFT ARE EXPECTED TO WARM A COUPLE OR A FEW DEGREES ON
SATURDAY AND WE SHOULD GENERALLY SEE WARMER TEMPS THAN TODAY...WITH
THE MOST NOTICEABLE CHANGES BEING OVR THE SOUTHEAST PLAINS.
OTHERWISE...THE WEATHER WILL REMAIN DRY WITH GENERALLY LIGHT WINDS.

LONG TERM...
(SATURDAY NIGHT THROUGH FRIDAY)

QUIET METEOROLOGICAL PATTERN TO CONTINUE OVER THE FORECAST DISTRICT
INTO AT LEAST MONDAY EVENING WITH MORE ACTIVE UNSETTLED CONDITIONS
RETURNING TO THE REGION AT TIMES FROM TUESDAY INTO LATE WEEK.

LATEST COMPUTER PROJECTIONS CONTINUE TO INDICATE THAT DRY
UPPER RIDGING PERSISTS INTO SATURDAY EVENING. DRY ZONAL TO
SOUTHWESTERLY UPPER FLOW SHOULD BE THEN BE NOTED OVER THE CWFA
FROM LATER SATURDAY EVENING INTO MONDAY EVENING IN ADVANCE OF
CLOSED UPPER LOW INITIALLY CENTERED OVER SOUTHERN CALIFORNIA AT
18Z TUESDAY. THIS UPPER SYSTEM THEN ROTATES ACROSS THE FORECAST
DISTRICT FROM TUESDAY INTO WEDNESDAY PROVIDING UNSETTLED AND
COOLER CONDITIONS DURING THIS TIME-FRAME.

ANOTHER UPPER SYSTEM IS PROJECTED TO IMPACT THE FORECAST DISTRICT BY
LATE WEEK ALLOWING BELOW SEASONAL COOL MID-DECEMBER TEMPERATURES AND
UNSETTLED CONDITIONS TO CONTINUE.

WARMEST TEMPERATURES OF THE LONGER TERM ARE STILL ANTICIPATED FROM
THIS WEEKEND INTO MONDAY WITH BELOW SEASONAL TEMPERATURES THEN
RETURNING TO THE CWFA DURING THE REMAINDER OF NEXT WEEK.
ALSO...GUSTY WINDS ARE EXPECTED AT TIMES FROM MONDAY NIGHT INTO
THURSDAY...ESPECIALLY EASTERN SECTIONS.

AVIATION...

IFR CIGS AND VSBYS ARE EXPECTED TO DEVELOP AGAIN AT KALS
TONIGHT...PROBABLY AFTER 03Z AND DISSIPATING BY ABOUT 16Z. IT LOOKS
LIKE KCOS SHOULD CONTINUE TO HAVE CLEAR OR MOSTLY CLEAR SKIES AND
THUS VFR CONDITIONS TONIGHT AND SATURDAY. IT LOOKS LIKE KPUB WILL
SEE THE RETURN OF MVFR OR IFR CONDITIONS...PROBABLY AFTER 02Z. THERE
IS SOME INDICATION IN THE FORECAST MODEL THAT THE LOW CLOUDS WL
DISSIPATE AROUND 10Z AS SOME WEAK WESTERLY WINDS DEVELOP...WITH VFR
CONDITIONS RETURNING.

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

10/44

AREA FORECAST DISCUSSION

NWS TOPEKA KS

353 AM CST SAT DEC 10 2011

.DISCUSSION...

SHORT RANGE FORECAST (TODAY AND SUNDAY)...

09Z WATER VAPOR IMAGERY AND ASSOCIATED 500 MB RUC ANALYSIS INDICATES
A BROAD 500 MB TROUGH CENTERED OVER EASTERN CANADA WITH ITS AXIS
RUNNING SOUTHWESTWARD THROUGH THE OHIO RIVER VALLEY...LEAVING
NORTHWEST FLOW OVER THE CENTRAL PLAINS. AT THE SURFACE THE RIDGE OF
HIGH PRESSURE IS MOVING OFF TO THE EAST ALLOWING FOR SOUTHERLY FLOW
TO RETURN TO THE AREA...ESPECIALLY ACROSS WESTERN AND CENTRAL
KANSAS. SOME AREAS ACROSS WESTERN/CENTRAL KANSAS HAS SEEN SOME FOG
DEVELOPMENT OVERNIGHT...BUT NORTHEAST KANSAS HAS THUS FAR BEEN
SPARED ANY WIDESPREAD FOG ISSUES...AND EXPECT THAT TO CONTINUE
THROUGH THE MORNING HOURS...SAVE A FEW AREAS OF PATCHY FOG WEST A
MARYSVILLE TO EMPORIA LINE. EXPECT SOUTHWESTERLY FLOW TO PICK UP
TODAY WHICH WILL ACT TO BRING A GRADUAL WARMING TREND THROUGH THE
WEEKEND. BY LATE IN THE WEEKEND THE SURFACE PRESSURE GRADIENT
BETWEEN THE SLOWLY DEPARTING SURFACE HIGH TO THE EAST AND A
DEVELOPING LOW ON THE LEE SIDE OF THE ROCKY MOUNTAINS WILL ALLOW
FOR THE SOUTHERLY FLOW TO PICK UP FOR SUNDAY AND MONDAY...BRINGING
GUSTY CONDITIONS FOR SUNDAY AND CONTINUING THE GRADUAL WARMING
TREND INTO MONDAY.

MID-RANGE AND EXTENDED FORECAST (MONDAY THROUGH FRIDAY)...

WITH A STRONG PUSH OF WARM/MOIST AIR INTO THE AREA FOR THE FIRST
PART OF THE WEEK EXPECT CLOUDS TO BUILD-IN. SATURATION IS EXPECTED
TO OCCUR AROUND 800 MB AS PARCELS ARE LIFTED ISENTROPICALLY. GIVEN
THE LACK OF DEEP MOISTURE DO NOT EXPECT ANYTHING MORE THAN SOME
AREAS OF DRIZZLE IN NORTH CENTRAL KANSAS...AND POSSIBLY A FEW
SPRINKLES IN FAR NORTHEAST KANSAS ON MONDAY WHERE ENHANCED LIFT
WOULD OCCUR IN RESPONSE TO A QUICKLY MOVING SUBTLE SHORTWAVE
TROUGH MOVING THROUGH THE PLAINS.

BY MID WEEK A DEEPLY AMPLIFIED SOUTHERN STREAM UPPER TROUGH WILL DIG
SOUTHWARD ALONG THE PACIFIC COASTLINE BEFORE EJECTING EASTWARD
ACROSS THE INTERIOR WESTERN CONUS. DECIDED TO SIDE WITH THE 00Z
ECMWF REGARDING THE TIMING OF THE EFFECTS FROM THIS SYSTEM. ON
TUESDAY A LEADING IMPULSE WILL PUSH OUT AHEAD OF THE MAIN WAVE
BRINGING A CHANCE FOR RAIN ON TUESDAY AFTERNOON. RAIN CHANCES
SHOULD CONTINUE AS THE MAIN UPPER TROUGH WILL PUSH INTO THE AREA
BY MID DAY ON WEDNESDAY. THERMAL PROFILES STILL SUGGEST THIS
SYSTEM WILL BE PRIMARILY RAIN. SOME MEAGER ELEVATED INSTABILITY
MAY BE PRESENT ONCE SHOWERS COMMENCE ON WEDNESDAY SO KEPT A
MENTION OF ISOLATED THUNDER WITHIN THE STRATIFORM RAIN. ASIDE FROM
AN ISOLATED THUNDER THREAT AREAS OF MODERATE RAIN MAY OCCUR WITHIN
THOSE POCKETS OF MODEST INSTABILITY. GIVEN THE WARM 850 MB TEMPS AND
THE PROGRESSION OF THE SYSTEM...THE ONLY REAL CHANCE FOR ANY
WINTRY TYPE OF PRECIPITATION WILL BE A MIX OF RAIN AND SNOW ACROSS
NORTH CENTRAL KANSAS ON THE WESTERN EDGE OF THE PRECIPITATION ONCE
THE COLDER AIR MOVES IN BEHIND THE PRECIP. EXPECT THE UPPER WAVE
AND ITS SUBSEQUENT RAINY CONDITIONS TO BE CLEAR OF NORTHEAST KANSAS BY
THURSDAY. ECMWF THEN PROGS A FAIRLY POTENT COLD FRONT MOVING INTO
THE CENTRAL PLAINS ALONG THE SOUTHERN EDGE OF A SOUTHWARD DIVING
RIDGE OF HIGH PRESSURE. EXPECT TEMPS TO BE QUITE COOLER FOR THE
END OF THE WEEK AS THE ARCTIC AIR MASS SETTLES INTO THE AREA.

.AVIATION...

STRATUS IS RAPIDLY ON THE DECREASE OVER THE AREA AND EXPECT VFR
CONDITIONS TO PERSIST THROUGH THE TAF PERIOD. LIGHT WINDS
OVERNIGHT WILL BECOME SOUTHERLY BY MID MORNING...WITH SUSTAINED
SPEEDS REACHING 10-12KTS BY AFTERNOON.

BLAIR

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

313 AM CST SAT DEC 10 2011

.DISCUSSION...

DAYS 1-2...

THE MAIN FORECAST CHALLENGES ARE HOW FAR EAST DENSE FOG CAN GET THIS
MORNING AND TEMPERATURES AND CLOUD COVER ON SUNDAY.

AS AN UPPER LEVEL TROUGH MOVES EAST TODAY DRY WEST TO NORTHWEST
UPPER LEVEL FLOW WILL PREVAIL. LIGHT SOUTHWEST WINDS ON THE BACKSIDE
OF A DEPARTING RIDGE OF SURFACE HIGH PRESSURE WAS ADVECTING HIGHER
DEWPOINTS BACK INTO FAR SOUTHWEST KANSAS WITH AREAS OF DENSE FOG.
THE NEWEST RUN OF THE HRRR MODEL SHOWS THE DENSE FOG AND STRATUS MAY
BE CLOSE TO DODGE CITY AND MEADE BY SUNRISE. WILL HAVE TO CONTINUE
TO MONITOR TRENDS TO SEE IF WE NEED TO EXPAND THE CURRENT DENSE FOG
ADVISORY MORE EAST. DEPENDING ON STRATUS SOME AREAS WILL NOT BE ABLE
TO SEE AN ALMOST TOTAL LUNAR ECLIPSE BY SUNRISE AND MOONSET. LATER
IN THE MORNING ANY SHALLOW FOG AND STRATUS SHOULD LIFT WITH SKIES
BECOMING SUNNY. SOUTHWEST WINDS WILL PICK UP A BIT TO 10 TO 15 MPH
WITH HIGHS FROM NEAR 40 OVER THE SNOW PACK IN THE FAR NORTHWEST FA
TO THE MID 40S ELSEWHERE.

FOR TONIGHT AN UPPER LEVEL DRY SHORTWAVE TROUGH MOVES THROUGH THE
PLAINS. A LEE TROUGH DEEPENS BY MORNING IN THE LEE OF THE ROCKIES
WITH A TIGHTENING PRESSURE GRADIENT OVER WESTERN KANSAS. SOUTH WINDS
SHOULD STAY MIXED IN THE 10 TO 20 MPH RANGE. MODEL BUFFER SOUNDINGS
SHOW SOME SHALLOW GROUND FOG BUT WITH A WELL MIXED BOUNDARY LAYER DO
NOT EXPECT STRATUS AT THIS TIME. WILL GO WITH LOWS FROM AROUND 20
FAR NORTHWEST TO THE MID 20S ELSEWHERE IN THE FA.

FOR SUNDAY WE TRANSITION TO SOUTHWEST UPPER LEVEL FLOW OVER THE
PLAINS WITH A 60 TO 70 KNOT JET OVER THE COLORADO ROCKIES. THE
STRONG FLOW WILL INDUCE A DEEPENING LEE LOW AND AN INCREASING
SURFACE PRESSURE GRADIENT OVER WESTERN AND CENTRAL KANSAS. BY MID TO
LATE MORNING AS MIXING OCCURS SOUTH WINDS WILL PICK UP TO 25 TO 35
MPH AND THIS MAY BE CLOSE TO A WIND ADVISORY. ALSO HIGHER DEWPOINTS
INTO THE MID 30S MOVE INTO WESTERN KANSAS. BUFFER SOUNDINGS SHOW LOW
LEVEL MOISTURE DEPTH INCREASING WITH STRATUS DEVELOPING IN THE
AFTERNOON. WILL SLOWLY INCREASE CLOUDS TO MOSTLY CLOUDY BY LATE
AFTERNOON. HIGH TEMPERATURES WILL BE TRICKY IF STRATUS DEVELOPS
HOWEVER STRONG MIXING MAY OFFSET THE STRATUS. FOR NOW WILL KEEP
HIGHS IN THE LOW TO MID 40S GOING.

ON SUNDAY NIGHT AN UPPER LEVEL JET MOVES OVER KANSAS WITH A LEE
TROUGH PUSHING A BIT EAST INTO EXTREME SOUTHWESTERN KANSAS. BUFFER
SOUNDINGS SHOW A SATURATED MOIST BOUNDARY LAYER UP TO AROUND 850MB
ALONG WITH SOUTH WINDS OF 15 TO 25 MPH. WINDS WILL BE LOWER CLOSER
TO THE TROUGH IN FAR SOUTHWEST KANSAS. ALSO HIGH CLOUDS WILL BECOME
THICKER TOWARDS MORNING. WILL GO WITH INCREASING CLOUDS WITH MOST OF
THE FA UNDER STRATUS EXCEPT FOR THE FAR WEST. LOWS WILL BE AROUND 30
FAR WEST TO THE MID TO UPPER 30S EAST WITH GOOD MIXING AND LOW
CLOUDS.

DAYS 3-7...

MEDIUM RANGE MODELS INDICATE AN UPPER LEVEL TROUGH OF LOW PRESSURE
PUSHING ASHORE IN EXTREME SOUTHERN CALIFORNIA MONDAY NIGHT INTO
TUESDAY BRINGING THE POSSIBILITY FOR PRECIP TO CENTRAL AND PORTIONS
OF WESTERN KANSAS LATE TUESDAY INTO WEDNESDAY. AS THE TROUGH ALOFT
APPROACHES, THE GEM, GFS, AND ECMWF SHOW A STRONG +130KT UPPER LEVEL
JET DEVELOPING ACROSS THE SOUTH PLAINS OF FAR WEST TEXAS NORTHEAST
INTO WESTERN KANSAS BY TUESDAY EVENING. MEANWHILE, AMPLE LOW LEVEL
MOISTURE IS PROJECTED TO NOSE NORTHWARD INTO SOUTH CENTRAL AND
PORTIONS OF SOUTHWEST KANSAS DURING THE DAY TUESDAY WITH H85
DEWPOINTS NEAR TO JUST ABOVE 5C. ALONG WITH STRONG UPPER LEVEL
DYNAMIC SUPPORT INCREASING, SURFACE LOW PRESSURE IS EXPECTED TO
DEVELOP GENERALLY IN EAST CENTRAL TO SOUTHEASTERN COLORADO BY
TUESDAY EVENING. COMBINED WITH SURFACE HIGH PRESSURE SET UP IN THE
EASTERN CONUS, THIS WILL HELP INCREASE LOW LEVEL FORCING ACROSS THE
CENTRAL PLAINS. AS A RESULT, RAIN WILL BE POSSIBLE IN SOUTH CENTRAL
KANSAS WHERE AVAILABLE MOISTURE WILL BE BEST WITH LESSER CHANCES
EXTENDING WEST INTO SOUTHWESTERN KANSAS. ISOLATED THUNDER CANNOT
BE COMPLETELY RULED OUT FOR FAR EASTERN PORTIONS OF THE CWA ON
WEDNESDAY.

TEMPERATURES WILL BE AT LEAST SEASONAL IF NOT SLIGHTLY ABOVE ON
MONDAY AS SURFACE LOW PRESSURE SET UP JUST OUR WEST AND SOUTHWEST
CONTINUES TO INFLUENCE MARGINAL WARM AIR ADVECTION INTO WESTERN
KANSAS. THE GEM, GFS, AND ECMWF SHOW H85 TEMPERATURES AROUND 2C TO
4C ACROSS THE CWA BY MONDAY AFTERNOON WITH THE WARMEST TEMPERATURES
IN OUR SOUTH. SHOULD SEE HIGHS UP INTO THE 40S(F) ACROSS THE
FORECAST AREA WITH LOWER TO MID 50S(F) POSSIBLE IN OUR SOUTHEAST.

.AVIATION...

DEVELOPING LOW LEVEL STRATUS/FOG WILL SPREAD NORTHEAST ACROSS
SOUTHWEST KANSAS EARLY THIS MORNING LOWERING CIGS DOWN TO IFR
CONDITIONS. AREAS OF FREEZING FOG WILL SPREAD NORTHEAST ACROSS THE
SAME GENERAL AREA LOWERING VSBYS DOWN TO A QUARTER MILE OR LESS IN
THE VICINITY OF KGCK AND KDDC BY SUNRISE WITH LOW VSBYS POSSIBLY
REACHING AS FAR NORTHEAST AS KHYS LATER THIS MORNING. IFR CIGS/VSBYS
ARE EXPECTED TO PERSIST THROUGH LATE MORNING BEFORE CONDITIONS BEGIN
TO IMPROVE WEST TO EAST ACROSS THE FORECAST AREA BY THIS AFTERNOON.
A LEE SIDE TROUGH WILL CONTINUE TO STRENGTHEN ACROSS EASTERN
COLORADO TODAY INFLUENCING SOUTH TO SOUTHWESTERLY WINDS 10 TO
20KT THROUGH TONIGHT.

.PRELIMINARY POINT TEMPS/POPS...
DDC 45 25 45 36 / 0 0 0 10
GCK 44 24 44 32 / 0 0 0 0
EHA 44 25 44 28 / 0 0 0 0
LBL 44 25 45 34 / 0 0 0 0
HYS 42 24 44 34 / 0 0 0 10
P28 46 26 47 37 / 0 0 10 10

.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM CST /8 AM MST/ THIS MORNING FOR
KSZ030-031-043>046-061>065-075>080-085>088.

FN06/32/32

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

1116 PM CST FRI DEC 9 2011

.UPDATE...

.AVIATION... /FOR THE 06Z TAF ISSUANCE/

TERMINAL AERODROME FORECASTS PRESENT A SIGNIFICANT CHALLENGE THIS
EVENING AS THE ACTUAL EXTENT OF THE CURRENT DEVELOPING FOG IS
LARGELY UNCERTAIN. A LARGE AREA OF EXPANDING FOG NEAR EXISTS
THROUGH THE ARKANSAS AND SMOKY HILL VALLEYS, AND LIFR/VLIFR FOG
CATEGORIES MAY BE LIKELY AT GARDEN CITY WITHIN THE NEXT 3-4 HOURS.
WE HAVE MUCH LESS CERTAINTY AT HAYS AND DODGE CITY AS THE NAM
CONFLICTS WITH THE VERY AGGRESSIVE RUC RAPID REFRESH MODEL WHICH
ENVELOPES THE ENTIRE FORECAST AREA IN DENSE FOG BY SATURDAY MORNING.
MOST PESSIMISTIC CONDITIONS WILL BE FORECAST AT GARDEN CITY IN THE
CRITICAL TAF PERIOD. - RUSSELL

.PREV DISCUSSION... /ISSUED 1036 PM CST FRI DEC 9 2011/

UPDATE...

WE HAVE HOISTED A DENSE FOG ADVISORY GENERALLY ALONG AND WEST OF
THE HIGHWAY 83 CORRIDOR THROUGH 15Z. THIS IS BASED ON CURRENT
TRENDS AS WELL AS MODEL TRENDS OF THE OVERNIGHT. DENSE FREEZING
FOG HAS DEVELOPED THROUGH THE ARKANSAS RIVER VALLEY OF KEARNEY
COUNTY THROUGH SYRACUSE, AND IS EXPANDING NORTHWARD THROUGH THE
SMOKY HILL VALLEY. FOLLOWING THE TRENDS OF THE NAM AND HRRR,
VISIBILITIES PROBABLY WILL RAPIDLY DROP SOUTHWARD AS WELL TO THE
PANHANDLE BY MIDNIGHT. EXPANSION OF THE ADVISORY EASTWARD MAY ALSO
BE NEEDED OVERNIGHT IF FOG EXPANDS FARTHER EAST WHICH IS WHAT
THE VERY AGGRESSIVE RAPID UPDATE INDICATES (AN OUTLIER TO THE
LESS AGGRESSIVE NAM). -RUSSELL

PREV DISCUSSION... /ISSUED 351 PM CST FRI DEC 9 2011/

SYNOPSIS...

CURRENTLY...SKIES ARE MOSTLY CLEAR WITH THE EXCEPTION OF ALONG THE
OKLAHOMA BORDER WHERE A FEW LOW CLOUDS REMAIN FROM THIS MORNING.
WINDS ARE GENERALLY FROM THE NORTHWEST AT 5 TO 10 MPH. TEMPERATURES
ARE IN THE LOWER TO MID 30S WITH THE EXCEPTION OF THE SOUTHWEST
CORNER OF THE CWA WHERE UPPER 20S ARE FOUND. THE CURRENT WEATHER
PICTURE CONSISTS OF AN UPPER LEVEL TROUGH ACROSS THE GREAT LAKES
EXTENDING SOUTHEAST ACROSS THE CENTRAL PLAINS AND AN UPPER LEVEL
HIGH ACROSS THE WESTERN UNITED STATES. HIGH PRESSURE IS FOUND ACROSS
THE NORTHERN PLAINS AT THE SURFACE WITH IT`S RIDGE AXIS EXTENDING
SOUTHWARD ACROSS THE HIGH PLAINS. INFORMATION FROM THIS MORNING`S
SOUNDING SHOW A SATURATED LAYER FROM THE SURFACE TO AROUND 850 MB
THEN BECOMES VERY DRY ABOVE THAT LAYER. THE SOUNDING ALSO SHOWS
NORTHERLY WINDS AT THE SURFACE SHIFTING TO THE WEST IN THE MID AND
UPPER PARTS OF THE ATMOSPHERE.

DISCUSSION...

DAYS 1-2...

THE SURFACE RIDGE OF HIGH PRESSURE MENTIONED IN THE SYNOPSIS WILL
MOVE EAST TODAY INTO TONIGHT SHIFTING NORTHERLY WINDS TO THE
SOUTHWEST BY TOMORROW MORNING. BEFORE TOMORROW MORNING...WINDS
SHOULD BECOME LIGHT AND VARIABLE OVERNIGHT ALLOWING FOR PATCHY FOG
TO REDEVELOP ACROSS WESTERN PORTIONS OF THE FORECAST AREA AFTER
MIDNIGHT. SOUTHWEST WINDS WILL INCREASE IN INTENSITY TOMORROW AS LEE
TROUGHING DEVELOPS ACROSS EASTERN COLORADO. SOUTHWEST WINDS CONTINUE
TOMORROW NIGHT INTO SUNDAY WITH BREEZY CONDITIONS EXPECTED SUNDAY
AFTERNOON. MOSTLY SUNNY SKIES AND DRY CONDITIONS SHOULD PREVAIL
THROUGH TOMORROW NIGHT DUE TO SURFACE HIGH PRESSURE TO OUR EAST AND
NORTHWEST FLOW ALOFT. CLOUDS ARE EXPECTED TO INCREASE ACROSS EASTERN
PORTIONS OF OUR FORECAST AREA ON SUNDAY AS MOISTURE FROM THE GULF OF
MEXICO ADVECTS NORTHWARD INTO CENTRAL KANSAS. LOWS TONIGHT ARE
ANTICIPATED TO BE IN THE UPPER TEENS TONIGHT THEN WARMING INTO THE
LOWER TO MID 20S TOMORROW NIGHT. HIGHS TOMORROW ARE EXPECTED TO BE
IN THE LOWER TO MID 40S WITH HIGHS IN THE MID TO UPPER 40S ON
SUNDAY.

DAYS 3-7...

AN ACTIVE WEATHER PATTERN WILL PERSIST THROUGH DECEMBER 19TH, WITH
A SERIES OF UPPER-LEVEL TROUGHS DROPPING SOUTHWARD INTO THE DESERT
SOUTHWEST AND THEN EJECTING NORTHEASTWARD ACROSS THE PLAINS. THIS
PATTERN WILL LEAD TO AMPLE GULF MOISTURE RETURN INTO THE SOUTHERN
AND CENTRAL PLAINS ALONG WITH PERIODIC CHANCES FOR PRECIPITATION.

ONE UPPER-LEVEL SYSTEM WILL MOVE SOUTHWARD TO JUST OFF THE
CALIFORNIA COAST BY MONDAY, PROGRESS INTO THE DESERT SOUTHWEST BY
TUESDAY, AND THEN EJECT ACROSS THE CENTRAL PLAINS ON WEDNESDAY.
AHEAD OF THIS SYSTEM THERE WILL BE A WEAK SURGE OF ARCTIC AIR THAT
WILL STALL OUT ACROSS NORTHERN OKLAHOMA OR SOUTHERN KANSAS. THIS
OUGHT TO SET UP A LOW-LEVEL THERMAL GRADIENT ACROSS OUR FORECAST AREA
BY TUESDAY MORNING. HAVING BEEN DRAWN INTO THE SOUTHERN AND CENTRAL
PLAINS SUNDAY AND MONDAY AHEAD OF A WEAKER UPPER-LEVEL DISTURBANCE,
LOW-LEVEL MOISTURE WILL BE PLENTIFUL BY TUESDAY. THEREFORE, AS MOIST
ISENTROPIC LIFT INCREASES WELL AHEAD OF THE UPPER-LEVEL SYSTEM ON
TUESDAY, WIDESPREAD STRATUS CLOUDS CAN BE EXPECTED ALONG WITH
INCREASING CHANCES FOR LIGHT RAIN AND DRIZZLE. THE EXACT
PLACEMENT OF THIS PRECIPITATION IS UNCERTAIN. THE 12Z SUITE OF
MODELS SHOW SURFACE TEMPERATURES ABOVE FREEZING EVEN AS FAR NORTH AS
INTERSTATE 70 BY TUESDAY AFTERNOON AS THE PRECIPITATION STARTS.
HOWEVER, SINCE THESE SHALLOW ARCTIC AIR INTRUSIONS ARE OFTEN
STRONGER THAN PROGGED, I WOULD NOT RULE OUT LIGHT FREEZING RAIN OR
FREEZING DRIZZLE ALONG THE INTERSTATE 70 CORRIDOR BY TUESDAY
AFTERNOON. EVEN THOUGH THE CENTRAL REGION COLLABORATED GRIDS
CURRENTLY SHOW UPPER 30S TO NEAR 40F NEAR WAKEENEY AND DIGHTON ON
TUESDAY AFTERNOON, DON`T BE TOO SURPRISED IF IT IS COLDER. RAIN
CHANCES WILL INCREASE BY TUESDAY NIGHT AND WEDNESDAY AS THE WARM
CONVEYOR BELT AHEAD OF THE UPPER-LEVEL SYSTEM BRINGS COPIOUS AMOUNTS
OF LOW-LEVEL MOISTURE INTO WESTERN KANSAS ALONG WITH MILDER
TEMPERATURES. SINCE THIS STRONG SYSTEM IS PROGGED TO BE SOMEWHAT
PROGRESSIVE AND PERHAPS EVEN A STRONG OPEN WAVE, THE CHANCES FOR
HEAVY RAINFALL LOOK LOWER IN FAR WESTERN KANSAS COMPARED TO
LOCATIONS FURTHER EAST SUCH AS STAFFORD, PRATT AND MEDICINE LODGE.
IN SIMPLIFIED TERMS, THIS IS DUE TO THE ALL TOO FAMILIAR RAIN SHADOW
EFFECT IN THE LEE OF THE ROCKIES. DEPENDING ON THE EXACT TRACK OF
THE SYSTEM AND ASSOCIATED FRONTAL PLACEMENTS, A WIDE RANGE OF HIGH
TEMPERATURES ARE POSSIBLE ON WEDNESDAY FROM THE 40S UP TO THE 60S.

THERE IS TREMENDOUS UNCERTAINTY IN THE EVOLUTION OF THE LARGE SCALE
PATTERN ACROSS THE EASTERN PACIFIC AND NORTH AMERICA AFTER
WEDNESDAY. AND THERE IS LITTLE CONSISTENCY FROM MODEL TO MODEL AND
FROM MODEL RUN TO MODEL RUN. HOWEVER, DESPITE ALL OF THESE
DIFFERENCES, THERE IS STILL A GENERAL THEME THAT CAN BE GLEANED
AMID ALL THE NOISE. THIS THEME SHOWS RENEWED UPPER-LEVEL TROUGHING
ACROSS THE SOUTHWESTERN UNITED STATES BY SATURDAY, A COLD SURGE DOWN
THE PLAINS AHEAD OF THE SYSTEM, AND ABUNDANT LOW-LEVEL MOISTURE
ADVECTING NORTHWARD FROM THE GULF OF MEXICO. SO PRECIPITATION
CHANCES WILL BE ON THE INCREASE BY SATURDAY INTO MONDAY. THERE IS FAR
TOO MUCH UNCERTAINTY TO DETERMINE WHETHER ENOUGH WARM AIR WILL SURGE
INTO WESTERN KANSAS BEFORE ANY PRECIPITATION STARTS TO PRECLUDE FROZEN
PRECIPITATION.

.PRELIMINARY POINT TEMPS/POPS...
DDC 19 44 25 45 / 0 0 0 10
GCK 17 42 23 44 / 0 0 0 0
EHA 22 44 26 44 / 0 0 0 0
LBL 19 44 24 45 / 0 0 0 10
HYS 15 41 25 44 / 0 0 0 10
P28 18 46 27 46 / 0 0 10 10

.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM CST /8 AM MST/ SATURDAY FOR KSZ043-
044-061>063-074>076-084>086.

FN99/99

AREA FORECAST DISCUSSION

NWS WAKEFIELD VA

139 AM EST SAT DEC 10 2011

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
FIRST WAVE OF SHWRS NOW MOVG NE ALONG ERN SHORE AREAS. SECOND WAVE
OF SHWRS MOVG NE FROM ERN NC AND BOTH RUC AND WRF MODELS HAVE THESE
MOVG NE ALONG VA / MD CSTL SCTNS THRU THE OVERNIGHT HRS. ALL THIS
AHEAD OF STRNG CDFRNT PROGGED TO PUSH THE LOW OFFSHORE SAT MORNING.
UPDATE WAS TO BUMP UP CLOUD COVERAGE TO M CLDY W AND CLDY E. KEPT
CHC POPS ALONG CSTL COUNTYS WITH A BUFFER ZONE OF SLGHT CHC POPS W
OF CHES BAY GIVEN CRNT RADAR TRENDS AND MODEL TRENDS.

.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY/...
HAVE SLOWED DOWN THE CLEARING SKY A BIT ON SAT AS LOW LEVEL FLOW
IS MORE N RATHER THAN NW. OVERALL...EXPECT MOSTLY CLOUDY SKIES IN
THE EAST IN THE MORNING...BECOMING PARTLY SUNNY IN THE AFTN
(CLEARING EARLIER ALONG/W OF I-95). HIGHS MAINLY IN THE UPPER 40S
TO LOWER 50S.

.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
PREDOMINATE VFR CONDITIONS ACROSS TERMINALS THIS MORNING. WEAK
PREFRONTAL SURFACE TROUGH OVER EASTERN VA AND NC...ALONG WITH A
WEAK LOW OFF THE NC COAST...ARE HELPING TO PRODUCE MVFR STRATUS
AND STRATOCU CLOUDS ALONG THE COASTAL AREAS UP THRU THE EASTERN
SHORE...WITH SOME SCT SHRAS/MVFR CONDS ACROSS SE COASTAL SITES. A
COLD FRONT TO THE WEST HAS STARTED TO MAKE SOME HEADWAY INTO
WESTERN VA EARLY THIS MORNING AND WILL PASS OFF THE COAST BY
SUNRISE. LOOK FOR A NW WIND SHIFT AND SOME GUSTY NNW WINDS LATER
TODAY THROUGH 20-22Z OR SO. OTHERWISE...BUILDING SFC HIGH
PRESSURE AND VFR CONDITIONS EXPECTED ACROSS THE TAF SITES.

OUTLOOK: HIGH PRESSURE OVER THE REGION WILL ALLOW FOR DRY WX AND VFR
WX FOR TONIGHT THROUGH THE MIDDLE OF NEXT WEEK.

.HYDROLOGY...
FLOOD WARNINGS REMAIN IN EFFECT FOR JAMES RIVER AT WESTHAM (MODERATE
FLOODING) AND RICHMOND CITY LOCKS (MINOR FLOODING). SEE FLSAKQ FOR
DETAILS.

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 4 PM EST SUNDAY
FOR ANZ634.
SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 1 PM EST SUNDAY
FOR ANZ631-632.
SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 6 PM EST SUNDAY
FOR ANZ633-650-652-654.
SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 6 PM EST THIS
EVENING FOR ANZ630.
SMALL CRAFT ADVISORY FROM 9 AM THIS MORNING TO 6 PM EST SUNDAY
FOR ANZ656-658.

$$
SYNOPSIS...LKB
NEAR TERM...MPR
SHORT TERM...LKB
LONG TERM...AJZ
AVIATION...MAM/JEF
MARINE...AJZ/JEF
HYDROLOGY...

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

1214 AM EST SAT DEC 10 2011

UPDATED AVIATION DISCUSSION FOR 06Z TAFS

.UPDATE...

.SHORT TERM /THROUGH 00Z SUNDAY/...

.LONG TERM DISCUSSION /SAT NGT THRU FRI/...

.AVIATION /FOR THE 06Z TAF ISSUANCE/...

ONGOING WESTERLY LAKE EFFECT SNOW WILL CONTINUE TO AFFECT KCMX
THROUGH THE NIGHT...BEFORE ENDING TOMORROW MORNING AS WINDS SHIFT TO
THE SW AND PUSH THE SNOW BANDS NORTH OF THE SITE. EXPECT MAINLY MVFR
CONDITIONS THROUGH THE NIGHT...BUT COULD REACH IFR VSBY LATE TONIGHT
AS THE DOMINATE BAND OVER CENTRAL HOUGHTON COUNTY SHIFTS N ACROSS
THE KEWEENAW PENINSULA. OTHERWISE...EXPECT VFR CONDITIONS AT THE
OTHER TWO SITES...DUE TO UNFAVORABLE LES WIND DIRECTIONS. A WEAK LOW
PRESSURE SYSTEM MOVING INTO THE NRN PLAINS WILL BRING INCREASING
CLOUDS TO ALL SITES ON SAT...BUT EXPECT CIGS TO BE VFR.
&&

.MARINE /FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE/...

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 9 AM EST THIS MORNING FOR MIZ006-
007.

LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

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

AREA FORECAST DISCUSSION...UPDATED AVIATION

NWS ST LOUIS MO

1139 PM CST FRI DEC 9 2011

.UPDATE...
/812 PM CST FRI DEC 9 2011/

BRITT

.DISCUSSION...
/259 PM CST FRI DEC 9 2011/

NOT A LOT GOING ON IN THE SHORT TERM...JUST DEALING WITH
TEMPS...BEYOND THAT MODELS CONTINUE TO BRING IN A DECENT SYSTEM BY
MIDWEEK NEXT WEEK.

BYRD

.AVIATION...
/1132 PM CST FRI DEC 9 2011/
VFR FLIGHT CONDITIONS AND LIGHT AND VARIABLE WINDS WILL PREVAIL
ACROSS THE BI-STATE AREA FOR THE REST OF THE NIGHT. A 4000-5000FT
DECK WILL CONTINUE TO MOVE ACROSS CENTRAL MISSOURI...AND CIGS MAY
FALL TO NEAR MVFR VALUES TOWARD SUNRISE...BUT CLOUDS MUCH BELOW
3000FT DO NOT APPEAR LIKELY. WIND WILL BECOME SOUTHWESTERLY ON
SATURDAY AS HIGH PRESSURE MOVES EAST OF THE AREA...AND VFR FLIGHT
CONDITIONS WILL CONTINUE TO PREVAIL.

SPECIFICS FOR KSTL...
VFR FLIGHT CONDITIONS AND LIGHT/VARIABLE WINDS WILL PREVAIL AT
LAMBERT FOR THE REMAINDER OF THE NIGHT. WILL LIKELY SEE
INTERMITTENT FEW CLOUDS AROUND 5000FT DRIFT BY THE TERMINAL...BUT
CIGS OVER CENTRAL MISSOURI SHOULD NOT AFFECT LAMBERT. WIND WILL
BECOME SOUTHWESTERLY LATE SATURDAY MORNING AS HIGH PRESSURE DRIFTS
EAST OF THE TERMINAL. VFR CONDITIONS WILL CONTINUE TO PREVAIL.

CARNEY

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&

WFO LSX

AREA FORECAST DISCUSSION

NWS TOPEKA KS

539 AM CST SAT DEC 10 2011

...UPDATE TO AVIATION...

.AVIATION...

VFR CONDITIONS EXPECTED THROUGH THE PERIOD. SMALL POCKET OF 9000FT
CLOUD DECK TO PASS OVER IN EARLY TAF PERIOD. OTHERWISE WINDS
BECOME SOUTHWESTERLY NEAR 12 KTS BY AFTERNOON HOURS THEN
DIMINISHING AGAIN OVERNIGHT LATE IN THE PERIOD. 67

.PREV DISCUSSION...
/ISSUED 353 AM CST SAT DEC 10 2011/

SHORT RANGE FORECAST (TODAY AND SUNDAY)...

MID-RANGE AND EXTENDED FORECAST (MONDAY THROUGH FRIDAY)...

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

500 AM CST SAT DEC 10 2011

.AVIATION...

FOR THE 12Z TAF ISSUANCE...

LOW LEVEL STRATUS/FOG WILL MOVE EAST ACROSS SOUTHWEST KANSAS EARLY
THIS MORNING WITH IFR CIGS/VSBYS LIKELY EARLY THIS MORNING IN THE
VICINITY OF KGCK, KDDC, AND POSSIBLY AS FAR NORTH AS KHYS. IFR
CIGS/VSBYS ARE EXPECTED TO PERSIST THROUGH LATE MORNING WITH
CONDITIONS BEGINNING TO GRADUALLY IMPROVE WEST TO EAST ACROSS
WESTERN PORTIONS OF THE FORECAST AREA BY THIS AFTERNOON. A LEE
SIDE TROUGH WILL CONTINUE TO STRENGTHEN ACROSS EASTERN COLORADO
TODAY INFLUENCING SOUTH TO SOUTHWESTERLY WINDS 10 TO 20KT THROUGH
TONIGHT.

.PREV DISCUSSION... /ISSUED 313 AM CST SAT DEC 10 2011/

DISCUSSION...

DAYS 1-2...

THE MAIN FORECAST CHALLENGES ARE HOW FAR EAST DENSE FOG CAN GET THIS
MORNING AND TEMPERATURES AND CLOUD COVER ON SUNDAY.

DAYS 3-7...

.PRELIMINARY POINT TEMPS/POPS...
DDC 45 25 45 36 / 0 0 0 10
GCK 44 24 44 32 / 0 0 0 0
EHA 44 25 44 28 / 0 0 0 0
LBL 44 25 45 34 / 0 0 0 0
HYS 42 24 44 34 / 0 0 0 10
P28 46 26 47 37 / 0 0 10 10

.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM CST /8 AM MST/ THIS MORNING FOR
KSZ030-031-043>046-061>065-075>080-085>088.

FN32/99/99

AREA FORECAST DISCUSSION

NWS WILMINGTON NC

944 AM EST SAT DEC 10 2011

.SYNOPSIS...
COLD AND DRY CONDITIONS WILL DEVELOP TODAY AND PERSIST THROUGH
TUESDAY AS ARCTIC HIGH PRESSURE MOVES TO OUR NORTH. WARMING
TEMPERATURE ARE EXPECTED WEDNESDAY THROUGH FRIDAY AS HIGH PRESSURE
MOVES OFFSHORE.

.NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM SATURDAY...THE NORTHERN AND SOUTHERN BRANCHES OF THE
JET STREAM ARE COMBINING FORCES ACROSS THE EASTERN U.S. THIS MORNING
AS A STRONG UPPER TROUGH MOVES EAST ACROSS THE GREAT LAKES. A WEAKER
SOUTHERN STREAM VORT MOVING JUST AHEAD OF THE STRONG NORTHERN
STREAM FEATURE IS CROSSING THE CAROLINAS CURRENTLY...HELPING TO
INDUCE A FEW LIGHT SPRINKLES ACROSS THE EASTERN CAROLINAS. THESE
SPRINKLES SHOULD LARGELY DISSIPATE AND/OR MOVE OFF THE COAST WITHIN
THE NEXT HOUR AS THE TROUGH EXITS TO THE EAST.

PLENTY OF LOW CLOUDS WILL LINGER THROUGH THE AFTERNOON ALONG THE
COAST...BUT INLAND AREAS SHOULD CLEAR OUT AS THE WESTERLY FLOW ABOVE
850 MB BRINGS DRIER AIR IN. JET STREAM CIRRUS WILL LINGER THROUGH
THE DAY AS WELL...BUT MODELS SHOW EVEN THAT MOISTURE PLUME EXITING
THE COAST (TEMPORARILY) THIS EVENING.

THE LARGEST FORECAST CONCERN TODAY IS HIGH TEMPERATURES. INCREASING
COLD ADVECTION WILL COUNTER MOST OF THE SUNSHINE THAT CAN SNEAK
THROUGH THE CLOUDS TODAY...CREATING ONLY A SLOWLY RISING TEMPERATURE
CURVE FOR MOST AREAS. HIGHS WILL PROBABLY ONLY REACH THE MID TO
UPPER 50S TODAY...NOT EVEN A 10 DEGREE RISE FROM CURRENT READINGS.
THE LATEST HRRR DID NOT INITIALIZE TOO PARTICULARLY WELL WITH
TEMPERATURES SO WE HAVE MADE NO SIGNIFICANT CHANGES TO THE HIGH TEMP
FORECAST NOW...BUT WILL MONITOR HOURLY TEMPERATURES CLOSELY FOR
LATER UPDATES.

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3 AM FRIDAY...HIGH PRESSURE WILL EXTEND INTO THE AREA
THROUGH THE PERIOD WHILE AN OLD FRONTAL BOUNDARY LINGERS OFF THE
COAST. THE FRONT WILL BE CLOSE ENOUGH SUNDAY NIGHT INTO MONDAY TO
YIELD AN INCREASE IN CLOUDS. THERE IS ALSO AN OUTSIDE SHOT FOR
LIGHT RAIN BUT THE PROBABILITY IS LOW ENOUGH PRESENTLY THAT NO
MENTION OF RAIN WILL BE MADE IN THE FORECAST. DECREASING CLOUDS ARE
ON TAP FOR MONDAY AFTERNOON AND NIGHT. BELOW NORMAL TEMPERATURES
EXPECTED BOTH DAYS WITH HIGHS IN THE LOW TO MID 50S SUNDAY AND MID
TO UPPER 50S MONDAY. LOWS EACH NIGHT WILL BE IN THE 30S.

.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 3 AM FRIDAY...IN GENERAL...HIGH PRESSURE WILL CONTROL AREA
WEATHER THROUGH THE PERIOD. THE RESULT WILL BE FAIR WEATHER AND A
WARMING TREND. ONE POTENTIAL FLY IN THE OINTMENT WILL TAKE THE FORM
OF A COLD FRONT APPROACHING FROM THE NORTH ALONG ABOUT THURSDAY
AFTERNOON. LATEST GUIDANCE KEEPS THIS FRONT WELL TO OUR NORTH BUT
IT IS POSSIBLE THAT IT COULD GET CLOSE ENOUGH TO INCREASE CLOUD
COVER AND BRING A CHANCE OF SHOWERS THURSDAY NIGHT.

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AS OF 12Z...HIGH CONFIDENCE IN VFR THROUGH THE VALID PERIOD.

WIDESPREAD 5-7 KFT CLOUDINESS AND SOME VERY LIGHT SHOWERS CURRENTLY
IMPACTING THE EASTERN CAROLINAS. THESE CLOUDS AND PRECIP ARE
ASSOCIATED WITH A MID LEVEL TROUGH WHICH WILL ROTATE ACROSS THE AREA
THROUGH THIS AFTN. HAVE MENTIONED TEMPO -SHRA FOR THE FIRST FEW
HOURS AT ALL THE TERMINALS...BUT INTENSITY WILL BE LIGHT ENOUGH THAT
VFR WILL PERSIST EVEN DURING ANY RAINFALL. AS THE TROUGH MOVE EAST
THROUGH THE DAY...SKY CONDITIONS WILL IMPROVE...BECOMING SKC TONIGHT
INLAND...WITH JUST REMAINING CI AT THE COAST.

WINDS THROUGH THE DAY WILL BE PREDOMINANTLY FROM THE NORTH AT 8 TO
12 KTS. PG TIGHTENS OVERNIGHT AHEAD OF ADVANCING HIGH PRESSURE FROM
THE NORTH...SO N WINDS OF 4-8 KTS WILL PERSIST THROUGH 12Z SUNDAY.

EXTENDED OUTLOOK...LOW CONFIDENCE IN SHOWERS AND STRATUS SUNDAY
NIGHT INTO MONDAY MORNING...ESPECIALLY NEAR THE COAST. OTRW...VFR
THROUGH THE EXTENDED.

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM SATURDAY...COLD AIR IS BUILDING INTO THE AREA THIS
MORNING AS ARCTIC HIGH PRESSURE OVER MISSOURI/SOUTHERN ILLINOIS
BUILDS EAST. THE PRESSURE GRADIENT WILL REALLY INCREASE TONIGHT AS
THE HIGH MOVES INTO THE OHIO VALLEY...CAUSING OUR WIND SPEEDS TO
INCREASE TO A SOLID 25 KT AWAY FROM SHORE WITH HIGHER GUSTS. UNTIL
THEN...NORTH WINDS 15-20 KT ARE EXPECTED DURING THE DAYLIGHT HOURS
TODAY...WITH A SHORT PERIOD WIND CHOP GRADUALLY BUILDING THROUGH THE
AFTERNOON. SPECTRAL WAVE PLOTS FROM FRYING PAN SHOALS SHOW THAT THE
SHORT PERIOD WAVES NOW "OUTWEIGH" THE MODEST SOUTHEAST SWELL WE HAVE
BEEN RECEIVING SINCE YESTERDAY...MAKING CONDITIONS QUITE ROUGH
ALREADY FOR MARINERS. THE SMALL CRAFT ADVISORY REMAINS IN EFFECT
BEGINNING AT 4 PM TODAY.

SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3 AM SATURDAY...PERIOD WILL BEGIN WITH NE WINDS RUNNING 20
TO 25 KT AS HIGH PRESSURE BUILDS IN FROM THE NW. WINDS WILL
GRADUALLY DIMINISH TO AROUND 15 KT THROUGH THE PERIOD AND TURN
TOWARD THE NORTH MONDAY NIGHT. SEAS OF 5 TO 7 FEET SUNDAY WILL
SUBSIDE TO 3 TO 4 FT BY MONDAY NIGHT WITH A FEW 5 FOOTERS STILL
POSSIBLE NEAR FRYING PAN SHOALS. SMALL CRAFT FLAGS WILL BE FLYING
FOR SUNDAY AND MAY NEED EXTENDED INTO SUNDAY NIGHT.

LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 3 AM SATURDAY...LIGHT N TO NW WINDS TUESDAY WILL CONTINUE
INTO WEDNESDAY BEFORE BECOMING W-SW BY WEDNESDAY NIGHT. SEAS WILL
SUBSIDE FROM 3 TO 4 FT TUESDAY MORNING TO 3 FT OR LESS BY WEDNESDAY
NIGHT.

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST
SUNDAY FOR AMZ250-252-254-256.

SYNOPSIS...31
NEAR TERM...TRA
SHORT TERM...31
LONG TERM...31
AVIATION...JDW

AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

1101 AM EST SAT DEC 10 2011

.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION THIS WEEKEND AND PROVIDE
FAIR AND DRY WEATHER THROUGH TUESDAY. SHOWERS ARE POSSIBLE DURING
THE MIDDLE OF THE WEEK. HIGH PRESSURE SHOULD RETURN BY NEXT
WEEKEND.

.NEAR TERM /UNTIL 7 PM THIS EVENING/...
WIDESPREAD BKN /ALBEIT RATHER SHALLOW/ STRATO CU PRODUCING SCATTERED
FLURRIES SEEN ACROSS THE NRN HALF OF PENN LATE THIS MORNING VIA A
FAIRLY WELL ALIGNED 290 MEAN BLYR FLOW.

THE SCENT VALLEYS WILL STAY MOSTLY SUNNY THIS AFTERNOON AS THE
COOLEST 850-500 MB TEMPS /AND BEST FETCH OF MOISTURE OFF LAKE ERIE/
SLIDE EAST ACROSS NRN PENN AND NEW YORK STATE.

LOCAL LAKE EFFECT TOOL AND LATEST 15Z RUC INDICATES THE
CURRENT...BKN WEAK LES BANDS CONSOLIDATING SOMEWHAT AND MOVING
FURTHER INLAND ON MORE OF A 27O DEG AXIS. THIS WILL BRING UP TO A
FEW INCHES OF ACCUM TO NWRN WARREN COUNTY...WHILE SURROUNDING
LOCATIONS THROUGHOUT WARREN...MCKEAN AND POTTER COUNTIES SEE JUST
A LIGHT COATING TO ONE INCH.

MAX TEMPS THIS AFTERNOON RANGING FROM THE MID TO UPPER 20S ACROSS
THE NW MTNS...TO AROUND 40 IN THE SE ZONES WILL BE 3-5F BELOW
NORMAL ACROSS THE SUSQ VALLEY...AND UP TO 7 OR 8F BELOW NORMAL
ACROSS THE MTNS.

.SHORT TERM /7 PM THIS EVENING THROUGH TUESDAY/...
LAKE EFFECT SHSN COULD DIMINISH OR HALT BEFORE A POSSIBLE RE-
DEVELOPMENT THIS EVENING/EARLY TONIGHT. THIS WILL BE DUE TO THE
BACKING FLOW AT THE LOW LEVELS WHILE 8H FLOW STAYS WNW FOR MOST OF
THE NIGHT. THIS IS KIND OF TYPICAL...AS PAST EXPERIENCE INDICATES
THAT WE OFTEN GET A LAST GASP BAND AS THE WAA BEGINS AND PINCHES
THE LINGERING MOISTURE IN A NARROW BAND OF CONVERGENCE LIFTING
NEWRD. ANY SHSN TONIGHT SHOULD BE NORTH OF ROUTE 6. THE CLEARING
THAT BECOMES NEARLY COMPLETE BY SUNRISE SUN AM WILL HELP THE TEMPS
DROP INTO THE TEENS EVERYWHERE ACROSS THE CWA. THE TYPICAL COLD
AIR DRAINAGE SITES LIKE KSEG/KTHV COULD BE 2-5F LOWER THAN
NEIGHBORING SITES.

THE NEXT FEW DAYS ARE THEN ABSOLUTELY UNEVENTFUL...WITH ABUNDANT
SUNSHINE THANKS TO THE GIANT 1038MB HIGH WHICH KEEPS ALL MOISTURE
AT BAY UNTIL LATER TUESDAY. THE TEMPS ON SUNDAY WILL ONLY REBOUND
TO A FEW DEGS MILDER THAN SAT AS WEAK WAA BEGINS. OVERNIGHT MINS
WILL MOST LIKELY BE MILDER ON THE RIDGES IN THE W WHERE WINDS MAY
STAY UP JUST A BIT VS THE CALM WINDS TO THE EAST. MONDAY LOOKS
LIKE NORMAL MAXES DESPITE ANOTHER CHILLY START. HIGH CLOUDS MAY
TRY TO MOVE OVERHEAD ON TUESDAY...BUT IT WILL STILL BE MOSTLY
SUNNY AND A FEW MORE DEGS WILL BE ADDED TO THE MAXES.

.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
NRN STREAM FRONT DROPS DOWN THROUGH NY STATE ON TUES NIGHT...AND
MAY MAKE IT INTO PA. BUT...THE HIGH WILL BE SITTING OVER THE
ENTIRE EASTERN SIDE OF THE CONTINENT AND SHOULD FEND IT OFF.
NO REAL MOISTURE WITH THAT BACKDOOR FRONT ANYWAY. WAA AND
INCREASING GULF MOISTURE TO OUR WEST WILL BRING AT LEAST SOME
LOWERED CLOUDS OVERHEAD TUES NIGHT/WED AS WARM FRONT WORKS TO THE
NORTH THROUGH THE OH VALLEY AND INTO THE LOWER GREAT LAKES. SO WE
SHOULD SEE SOME CHC OF A BRIEF SHOWER FROM TUES NIGHT INTO
WED...BUT BULK OF THE TIME WILL BE DRY.

GIANT STORM WILL DEEPEN OVER THE MS VALLEY AND GO INTO THE UPPER
GREAT LAKES ON THURS. THIS WILL LEAD TO ANOTHER ROUND OF RATHER
STRONG SW FLOW LOCALLY ON THU...BUT SHOWERS SHOULD HOLD OFF UNTIL
THU NIGHT WITH COLD FRONT.

THE AIRMASS BEHIND THE FRONT IS NOT REAL COLD...HEIGHTS ARE QUITE
HIGH...THUS NOT SEEING MUCH IF ANY LAKE EFFECT WITH SW FLOW BEHIND
THE COLD FRONT. PATTERN DIFFS BETWEEN GFS AND ECMWF AT LONGEST
RANGES WILL KEEP UNCERTAINTY HIGH AND SLIGHT/LOW CHC POPS IN FOR
DAY7.

.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
12Z TAFS ADJUSTED FOR CURRENT CONDITIONS.

THE NW FLOW OF COLDER AIR CONTINUES TO ADVECT IN...THE LAKE EFFECT
CONTINUES TO MOVE IN SHORE WHICH WILL ALLOW FOR SEVERAL HOURS OF
SNOW SHOWERS AND FLURRIES. THESE WILL PERSIST UNTIL EARLY
EVENING...IN WHICH THE FLOW WILL BE ABATED AND THE MIXING CUT
OFF. EXPECT ANY LIGHT SNOW TO BE DONE BY 00Z. VFR CONDITIONS WILL
CONTINUE THROUGHOUT THE PERIOD.

HIGH PRESSURE WILL BUILD OVER PA LATE TODAY INTO SUNDAY. VFR
CONDITIONS WILL THEN PREVAIL THROUGH EARLY NEXT WEEK.

OUTLOOK...
SUN-TUE...NO SIG WX/VFR.
WED...CHC OF A SHOWER...VFR/MVFR.

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...DANGELO
LONG TERM...DANGELO/MARTIN
AVIATION...CERU/MARTIN

AREA FORECAST DISCUSSION

NWS LA CROSSE WI

955 AM CST SAT DEC 10 2011

.SHORT TERM...
955 AM CST SAT DEC 10 2011

UPDATED SKY TRENDS TODAY TOWARD CLOUDIER CONDITIONS GIVEN
SOUTHWEST WINDS/WARM AIR ADVECTION OVER THE EXISTING SNOW PACK.
LATEST IR IMAGERY SHOWING STRATUS WITH BASES IN THE 1500-3000FT
RANGE ADVECTING EAST/NORTHEAST ACROSS IA TOWARD THE FORECAST AREA.
MEANWHILE ...MID-LEVEL CLOUDS WERE ADVECTING SOUTHEASTWARD ACROSS
NORTHERN MN TOWARD THE AREA IN ISENTROPIC LIFT AHEAD OF A WARM
FRONT ACROSS THE EASTERN PART OF THE DAKOTAS. RUC MODEL SHOWING
EXPANDING RH IN THE 0.5-1KM LAYER BELOW AN INVERSION THROUGH
TODAY. RESULT IS EXPECTED TO BE AN INCREASE IN STRATUS IN ADDITION
TO THE INCREASE IN ALTOCUMULUS ACROSS THE AREA AS THE DAY WEARS
ON.

.LONG TERM...TUESDAY THROUGH FRIDAY
300 AM CST SAT DEC 10 2011

STILL LOTS OF UNCERTAINTY IN THIS TIME WITH REGARDS TO THE SYSTEM
IN THE WEDNESDAY/THURSDAY TIME FRAME. MODEL TRENDS IN BOTH THE GFS
AND ECMWF IS A SHIFT SOUTHEAST WITH THE SURFACE LOW TRACK. ALONG
WITH SOME TIMING DIFFERENCES. GFS FURTHEST SOUTH TAKING THE LOW
CROSS CENTRAL ILLINOIS...WHILE THE ECMWF LIFTS THE LOW THROUGH IOWA
AND ACROSS SOUTHWEST WISCONSIN. 10.00Z GEM SIDES CLOSER WITH THE
ECMWF WITH LOW TRACKING FROM IOWA INTO SOUTHERN WISCONSIN. OBVIOUSLY
WITH THESE DIFFERENCES THERE IS STILL A QUESTION ON PRECIPITATION
TYPE AND WILL CONTINUE TO MENTION RAIN/SNOW. ACCUMULATING SNOW QUITE
LIKELY FROM THIS...BUT WHERE WILL IT BE IS THE MILLION DOLLAR
QUESTION. MODEL CONSENSUS IS FOR THE HIGHEST PROBABILITIES
WEDNESDAY NIGHT AND THURSDAY. SYSTEM WILL LIFT AWAY FROM THE AREA
FRIDAY WITH COLDER AIR RETURNING TO THE REGION...WITH HIGHS IN THE
20S.

.AVIATION...TODAY AND TONIGHT
535 AM CST SAT DEC 10 2011

VFR CONDITIONS ARE EXPECTED THROUGH THE FORECAST PERIOD. HIGH
PRESSURE WILL SLIDE EAST OF THE REGION TODAY AS A SURFACE TROUGH
DEVELOPS ACROSS THE NORTHERN PLAINS. LOOK FOR SOUTHWEST WINDS TO
INCREASE INTO THE 12 TO 15 KT RANGE...WITH GUSTS TO AROUND 21 KTS
POSSIBLE. A SCT-BKN CLOUD DECK WITH BASES RANGING FORM 8 TO 12
KFT...WILL MOVE FROM NORTHWEST TO SOUTHEAST ACROSS THE TAF SITES
THIS MORNING INTO THE EARLY AFTERNOON HOURS. LOOK FOR SKIES TO
CLEAR LATE THIS AFTERNOON. FORECAST SOUNDINGS ARE SHOWING LOW
LEVEL MOISTURE INCREASING ACROSS THE AREA THIS EVENING INTO THE
OVERNIGHT HOURS...WITH THE POTENTIAL FOR A LOW STRATUS DECK TO
DEVELOP. WINDS FROM JUST ABOVE THE SURFACE THROUGH 1KFT AT 13 TO
25 KTS...SHOULD PROMOTE ENOUGH MIXING TO INHIBIT LOW STRATUS
DEVELOPMENT BUT WILL HAVE TO CLOSELY MONITOR THIS LATE THIS
AFTERNOON INTO THIS EVENING. VFR CONDITIONS ARE ANTICIPATED DURING
THE OVERNIGHT HOURS...UNLESS THE LOW STRATUS DEVELOPS THEN
MVFR/IFR CONDITIONS WOULD BE POSSIBLE.

.ARX WATCHES/WARNINGS/ADVISORIES...
300 AM CST SAT DEC 10 2011

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

SHORT TERM...DAS
LONG TERM....RABERDING
AVIATION.....WETENKAMP

AREA FORECAST DISCUSSION

NWS PUEBLO CO

306 PM MST SAT DEC 10 2011

.SHORT TERM...
(TONIGHT AND SUNDAY)

WE WILL CONTINUE TO SEE CLEAR SKIES TONIGHT. THE FLOW ALOFT TONIGHT
IS EXPECTED TO BECOME MORE WESTERLY WITH A LEE SFC TROF DEVELOPING.
THE WESTERLY WINDS NEAR THE MTS SHOULD KEEP TEMPS A BIT WARMER THAN
THEY WERE LAST NIGHT. TEMPS OVR THE SERN PLAINS WL ALSO BE A LITTLE
WARMER MOST AREAS. THE SAN LUIS VALLEY HOWEVER SHOULD STILL SEE
SINGLE DIGITS ABOVE AND BELOW ZERO FOR LOW TEMPS TONIGHT. THE NAM
BUFKIT SOUNDING FOR KALS SHOWS THE POTENTIAL FOR STRATUS AND FOG
DEVELOPING. WE DIDN`T SEE THAT HAPPEN THIS MORNING AND I HAVE LOW
CONFIDENCE THAT IT WILL HAPPEN TONIGHT. THE RUC AND NAM SOUNDINGS
FOR KLHX AND KLAA ALSO SHOW THE POTENTIAL FOR STRATUS/FOG DEVELOPING
AGAIN. I AM NOT REAL CONFIDENT IN THIS EITHER. SO FOR NOW WL LEAVE
OUT THE MENTION OF CLOUDS AND/OR FOG.

ANOTHER DRY DAY IS EXPECTED SUNDAY WITH BEING A LITTLE WARMER THAN
TODAY IN MOST AREAS...ALTHOUGH THE SAN LUIS VALLEY MAY SEE SIMILAR
OR JUST SLIGHTLY WARMER TEMPS THAN TODAY. THE NAM IS SHOWING LOW
LEVEL MOISTURE WORKING ITS WAY NORTHWARD SUNDAY AFTERNOON...AND INTO
THE FAR SERN CORNER OF THE STATE (MOSTLY BACA COUNTY)...SO WE WL
PROBABLY SEE AN INCREASE IN CLOUDS OVR THAT AREA.

.LONG TERM...
(SUNDAY NIGHT THROUGH SATURDAY)

METEOROLOGICAL ISSUES THIS LONGER TERM CYCLE INCLUDE BUT ARE NOT
LIMITED TO POPS...POTENTIAL SNOW AMOUNTS(ESPECIALLY OVER SECTIONS
OF THE CENTRAL AND SOUTHWESTERN MOUNTAINS)...GUSTY WINDS AT TIMES
AND TEMPERATURES.

RECENT LONGER TERM MODEL SOLUTIONS SUGGEST THAT THE DRY SOUTHWEST
UPPER FLOW OF SUNDAY NIGHT INTO AT LEAST EARLY MONDAY AFTERNOON
WILL GIVE WAY TO INCREASING PRECIPITATION CHANCES(AS CLOSED UPPER
LOW DEVELOPS OVER FAR SOUTHERN CALIFORNIA BY 06Z TUESDAY AND THEN
MOVES INTO THE 4-CORNERS REGION BY TUESDAY NIGHT) FROM LATER
MONDAY AFTERNOON INTO AT LEAST TUESDAY EVENING(ESPECIALLY OVER
ZONE 68/EASTERN SAN JUAN MOUNTAINS WHERE LATEST MODEL PROJECTIONS
INDICATE THAT SNOW AMOUNTS IN EXCESS OF 12 INCHES MAY OCCUR FROM
MONDAY NIGHT INTO TUESDAY...I.E. MY 5TH AND 6TH PERIODS).

AT THIS TIME...WILL HOLD OFF ON ANY WINTER HIGHLIGHTS FOR NOW SINCE
EVENT IS STILL A BIT TOO FAR OUT IN TIME...HOWEVER IF LATEST
COMPUTER MODEL TRENDS PERSIST...WFO PUEBLO WILL LIKELY BE ISSUING
WINTER WEATHER HIGHLIGHTS...ESPECIALLY FOR AREAS SUCH AS ZONE 68
DURING THE NEXT DAY OR TWO...PLEASE STAY TUNED.

ELSEWHERE...AS INITIAL UPPER SYSTEM PUSHES ACROSS THE REGION FROM
TUESDAY NIGHT INTO WEDNESDAY...ANTICIPATE INCREASED CLOUD/SHOWER
ACTIVITY IN COMBINATION WITH COOLER TEMPERATURES.

FORECAST DISTRICT THEN RECEIVES A BRIEF RESPITE THURSDAY BEFORE NEXT
CLOSED LOW TRAVELS FROM THE PACIFIC NORTHWEST ON THURSDAY AND
SETTLES OVER FAR SOUTHERN CALIFORNIA FROM FRIDAY EVENING INTO
SATURDAY.

THIS NEXT UPPER SYSTEM SHOULD AGAIN IMPACT WESTERN AND NORTHERN
PORTIONS OF THE CWFA WITH UNSETTLED CONDITIONS FROM LATER THURSDAY
INTO AT LEAST FRIDAY...ALTHOUGH PRIMARY PRECIPITATION FOCUS WITH
THIS SYSTEM APPEARS TO REMAIN WELL SOUTH THROUGH SOUTHWEST OF THE
CWFA DURING THIS TIME-FRAME.

IN ADDITION...TEMPERATURES GENERALLY RUNNING NEAR OR BELOW MID-DECEMBER
SEASONAL AVERAGES ARE ANTICIPATED DURING THE LONGER TERM.
FINALLY...GUSTY WINDS WILL BE POSSIBLE AT TIMES FROM TUESDAY INTO
TUESDAY NIGHT AND THEN AGAIN BY NEXT FRIDAY(ESPECIALLY EASTERN
SECTIONS).

.AVIATION...

EXPECT VFR CONDITIONS FOR THE NEXT 24 HOURS AT KCOS AND KPUB. KALS
WL LIKELY HAVE VFR CONDITIONS DURING THIS PERIOD AS WELL...HOWEVER
ONE MODEL SOUNDING IS SHOWING THE POTENTIAL FOR THE DEVELOPMENT OF
STRATUS/FOG TONIGHT. SINCE IT DIDN`T HAPPEN THIS MORNING AND THE
MODEL HAD FORECAST IT YESTERDAY...MY CONFIDENCE IN THE STATUS/FOG
DEVELOPING IS LOW AND WL LEAVE IT OUT OF THE TAF.

.PUB WATCHES/WARNINGS/ADVISORIES...

NONE.

AREA FORECAST DISCUSSION

NWS TOPEKA KS

336 PM CST SAT DEC 10 2011

.DISCUSSION...

WATER VAPOR SHOWING UPPER LEVEL HIGH PRESSURE OVER THE ROCKIES WITH
DRY NORTHWEST FLOW ALOFT ACROSS THE COUNTY WARNING AREA (CWA). AS THE
RIDGE ADVANCES EASTWARD AND FLATTENS...THE FLOW ACROSS THE CWA WILL
BECOME MORE ZONAL. THIS WILL ALLOW LEESIDE SFC TROUGHING TO THE WEST
TO REMAIN IN PLACE AND KEEP SOUTH/SOUTHWESTERLY FLOW IN THE LOWER
LEVELS IN PLACE ACROSS THE CWA THROUGH SUNDAY. STRATUS DECK AT MID
AFTERNOON ACROSS PORTIONS OF CENTRAL/SOUTH CENTRAL KS CONTINUES TO
ERODE AND DO NOT EXPECT MUCH IF ANY OF IT TO MAKE IT INTO THE CWA
THIS AFTERNOON OR EVENING...ALTHOUGH THIS MOISTURE AXIS WILL REMAIN
IN PLACE AND BY SUNDAY AFTERNOON EXPECT MORE CLOUDS TO DEVELOP
ACROSS THE WESTERN CWA AS 850 DEWPOINTS STEADILY INCREASE WITHIN
THIS AXIS.

EXPECT MIXING TONIGHT TO BE AN OFFSETTING FACTOR FOR SIGNIFICANT FOG
TONIGHT...SO WILL LEAVE IT OUT OF GRIDS FOR NOW. WITH PERSISTENT
SOUTH/SOUTHWEST FLOW ON SUNDAY...WEAK WARM AIR ADVECTION AND MOSTLY
SUNNY SKIES THROUGH PEAK HEATING...MIDDLE TO UPPER 40S STILL LOOK ON
TARGET FOR THE CWA. 63

WARM MOIST ADVECTION BEGINS IN EARNEST SUNDAY NIGHT INTO FRIDAY
MORNING. THERE IS SOME WEAK ISENTROPIC LIFT ON THE 290K SURFACE
SUNDAY NIGHT INTO MONDAY MORNING. FORECAST SOUNDING SATURATE IN THE
LOWER LEVELS BUT LIFT IS MINIMAL. SOME SUPPORT FOR FORCING WILL COME
FROM A PASSING WAVE LATE SUNDAY NIGHT WHICH MAY SPIT OUT SOME LIGHT
RAIN IN THE NORTHEAST CORNER. FURTHER WEST SOUNDINGS A BIT MORE
FAVORABLE FOR SOME DRIZZLE AND FOG SO WILL MAINTAIN FROM PREVIOUS
FORECAST. MONDAY LOOKING MAINLY DRY AS THE UPPER WAVE MOVES OFF AND
850 MB FLOW BECOMES MORE SOUTHWESTERLY FOCUSING MOISTURE TO THE
NORTHEAST OF THE CWA HOWEVER COULD HAVE SOME EARLY MORNING DRIZZLE.
TEMPERATURES WARM INTO THE MID 40S.

IN THE TUESDAY THROUGH THURSDAY PERIOD AN AMPLIFIED UPPER TROUGH
WILL MOVE OUT OF THE SOUTHWEST U.S AND ACROSS THE CENTRAL PLAINS.
TEMPERATURE PROFILES SUGGEST THAT PRECIPITATION WILL BE IN THE FORM
OF RAIN FOR THE PERIOD. WARM ADVECTION LATE MONDAY NIGHT INTO
TUESDAY MORNING WITH INCREASING MOISTURE AND ISENTROPIC LIFT ALONG
WITH SOME ENERGY EJECTING FROM THE UPPER TROUGH TO BRING SOME
CHANCES FOR LIGHT RAIN. THE UPPER TROUGH WILL MOVE ACROSS THE PLAINS
WEDNESDAY AND WEDNESDAY NIGHT. SOME ELEVATED INSTABILITY MAY BE
PRESENT ON WEDNESDAY INTO WEDNESDAY EVENING SO KEPT MENTION OF
ISOLATED THUNDERSTORMS ALONG WITH SHOWERS. ON THE BACK SIDE OF THE
SYSTEM WEDNESDAY NIGHT SOUNDINGS NOT CONDUCIVE TO PRECIPITATION
AFTER 06Z THURSDAY IN THE NORTHWEST SO DID NOT INCLUDE ANY FROZEN
PRECIPITATION LATE IN THE NIGHT. UPPER WAVE MOVES OFF BY EARLY
THURSDAY THEN MODELS DIVERGE IN SOLUTIONS NEAR THE END OF THE PERIOD
FOR FRIDAY AND SATURDAY. GIVEN MODEL UNCERTAINTY LEFT FORECAST DRY
FOR FRIDAY AND SATURDAY. TEMPERATURES WILL BE COLDER FOR THE END OF
THE WEEK WITH ARCTIC AIR IN PLACE OVER THE REGION.

.AVIATION...

CURRENT SATELLITE TRENDS SHOWS THE NORTHEASTWARD TRACK OF THE
FOG/STRATUS DECK OVER SW KANSAS. WHILE KMHK IS THE CLOSEST
AFFECTED TERMINAL...THE DEWPOINT DEPRESSIONS HAVE INCREASED ENOUGH
TO BELIEVE STRATUS DECK WILL NOT REACH THE TERMINALS AND HAVE
THEREFORE KEPT VFR CONDITIONS. SOUTHWEST WINDS OVER 10KTS THROUGH
THE AFTERNOON WILL CALM AFTER SUNSET WITH THE NAM AND RUC MODELS
INDICATING THE FOG/STRATUS TO DEVELOP OVER KTOP AND KMHK SATURDAY
EVENING. AT THIS TIME...HIGHER ELEVATION OVER KFOE MAY HOLD BACK
FOG WITH SOUTH WINDS SUSTAINED ABOVE 5 KTS. WILL CONTINUE TO
MONITOR STRATUS/FOG DECK AND AMEND AS NECESSARY.

BOWEN

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS WICHITA KS

333 PM CST SAT DEC 10 2011

.DISCUSSION...

MAIN CONCERN WILL BE STRATUS/FOG TONIGHT INTO SUN...THEN CHANCE OF
SHOWERS FOR TUE THROUGH THU.

TONIGHT:
SFC WINDS HAVE GRADUALLY SHIFTED AROUND TO THE SW TODAY AS THE UPPER
FLOW BECOMES MORE ZONAL. THIS RETURN FLOW HAS ALSO ADVECTED IN A LOW
CLOUD DECK FROM THE PANHANDLE OF TX/OK INTO SOUTH CENTRAL KS...WITH
THIS LOW CLOUD DECK EXPECTED TO BE PROBLEMATIC THIS EVE/TONIGHT.
NONE OF THE SHORT TERM MODELS ARE HANDLING THIS CLOUD DECK
WELL...BUT NOT REAL SURE WE WILL SEE THIS DECK DISSIPATE MUCH
OVERNIGHT...AS WEAK WARM ADVECTION CONTINUES ACROSS THE AREA..WITH
LITTLE OR NO MIXING. COULD ALSO SEE SOME PATCHY FOG ASSOCIATED WITH
IT...AS LOW LEVEL MOISTURE REMAINS TRAPPED UNDER THE CLOUD DECK..SO
WILL MENTION THIS AS WELL.

SUN-MON:
FAIRLY CERTAIN STRATUS DECK WILL BE AROUND ON SUN...WHICH WILL KEEP
MAX TEMPS DOWN SOME...BUT WEAK WARM ADVECTION WILL LEAD TO TEMPS A
LITTLE WARMER THAN TODAY. NAM/WRF AND GFS SEEM TO HAVE A LITTLE
BETTER HANDLE ON CLOUDS AND POSSIBLE DRIZZLE/FOG FOR SUN
NIGHT...ESPECIALLY ACROSS CEN KS. WILL HAVE TO KEEP A CLOSE EYE ON
TEMPS NORTH OF INTERSTATE 70...AS THIS AREA MAY SEE TEMPS HOVER NEAR
FREEZING...WHICH COULD LEAD TO FREEZING DRIZZLE THREAT. FOR NOW
THINK WEAK WARM ADVECTION WILL KEEP TEMPS JUST ABOVE FREEZING AND
ALL LIQUID. CERTAINLY LOOKS LIKE A GREY COOL DAY FOR MOST AREAS ON
SUN INTO MON. COULD ALSO SEE SOME OF THIS DRIZZLE REMAIN ACROSS MOST
OF CEN KS EARLY ON MON AS WELL.

TUE-THU:
MODELS STILL DIFFER ON HOW THE SHORTWAVE...THAT WILL BE CENTERED IN
THE SW US...WILL LIFT OUT INTO THE PLAINS FOR THE MIDDLE OF THE
WEEK. BOTH THE GFS AND ECMWF HAVE BEEN CONSISTENT IN STICKING WITH
THEIR DIFFERING SOLUTIONS. WITH THE ECMWF MORE PROGRESSIVE...WHILE
THE GFS IS DEEPER/STRONGER AND HAS MORE NEGATIVE TILT AS IT COMES
INTO THE PLAINS. WITH THAT SAID...THE LATEST ECMWF MY BE TRENDING
TOWARDS THE FURTHER SOUTH GFS SOLUTION. TIMING OF THE SYSTEM IN THE
TWO MODELS SEEMS TO BE THE THING THEY AGREE ON THE MOST...WITH THE
CONTINUED LOW LEVEL MOISTURE RETURN AND WARM ADVECTION EXPECTED TO
LEAD TO A CHANCE OF LIGHT RAIN FOR MOST OF THE AREA TUE. THE MAIN
PRECIP SHOW STILL LOOKS TO BE ON WED...AS SYNOPTIC LIFT FROM THE
MAIN SHORTWAVE LIFTS NORTHEAST ACROSS THE PLAINS...WITH LOTS OF LIFT
AND MOISTURE AROUND FOR A SOLID SHOWER CHANCE...FOR MOST AREAS. WILL
CONTINUE TO MENTION A FEW RUMBLES OF THUNDER ACROSS SRN/SERN KS AS
THIS SYSTEM MOVES THROUGH...WITH ALL THE PRECIP IN THE FORM OF
LIQUID. SYSTEM WILL MAKE ITS WAYS TO THE EAST OF THE AREA FOR LATE
WED NIGHT WITH COLDER AIR FILTERING INTO THE AREA FOR THU.

REST OF THE EXTENDED:
SOME UNCERTAINTY ON HOW THE BEGINNING OF THE WEEKEND WILL PLAY
OUT...WITH THE GFS DROPPING A COLD CANADIAN AIRMASS INTO THE AREA.
BUT THE ECMWF SHOWS QUITE A BAROCLINIC ZONE ACROSS THE AREA FOR
FRI...WHICH COULD LEAD TO A LIGHT SNOW CHANCE. MODEL CONSENSUS
SUGGESTS KEEPING THIS CHANCE IN FOR NOW.

KETCHAM

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

IFR CIGS CONTINUE TO IMPACT MUCH OF THE AREA EARLY THIS AFTERNOON
AND RECENT SATELLITE TRENDS SUPPORT THIS AREA EXPANDING TO INCLUDE
ALL TERMINALS WITH THE EXCEPTION OF KCNU. BY 20-21Z...LOW CLOUDS MAY
START TO BECOME SCATTERED BUT MVFR/IFR MAY RAPIDLY RETURN THIS
EVENING WITH LIGHT SOUTHERLY WINDS AND VERY LOW TEMPERATURE-
DEWPOINT SPREADS. THE LATEST HRRR SUPPORTS MAINTAINING LOW CIGS
AND REDUCTIONS IN VISIBILITY INTO THE OVERNIGHT HOURS AND UPCOMING
AMENDMENTS MAY BECOME NECESSARY AS CONFIDENCE INCREASES.

MCGUIRE

.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 26 46 35 49 / 0 10 10 10
HUTCHINSON 26 44 34 50 / 0 10 10 10
NEWTON 26 43 35 47 / 0 10 10 10
ELDORADO 27 45 35 47 / 0 10 10 10
WINFIELD-KWLD 27 47 35 49 / 0 10 10 10
RUSSELL 23 43 34 47 / 0 10 10 10
GREAT BEND 24 45 34 48 / 0 10 10 10
SALINA 25 46 35 48 / 0 10 10 10
MCPHERSON 26 44 34 48 / 0 10 10 10
COFFEYVILLE 27 48 33 46 / 0 10 10 10
CHANUTE 26 46 34 45 / 0 0 10 10
IOLA 26 45 34 45 / 0 0 10 10
PARSONS-KPPF 26 47 34 45 / 0 0 10 10

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

AREA FORECAST DISCUSSION

NWS WICHITA KS

1211 PM CST SAT DEC 10 2011

.UPDATE...

WIDESPREAD STRATUS AND FOG CONTINUE TO IMPACT MUCH OF SOUTH
CENTRAL AND CENTRAL KANSAS. THIS AREA OF REDUCED VISIBILITIES AND
LOW CLOUDS WILL CONTINUE TO SPREAD SLOWLY NORTHEAST BEFORE MIXING
OUT BY MID-LATE AFTERNOON. TRENDED HIGHS DOWN ACROSS MUCH OF THE WESTERN
ZONES WHERE TEMPERATURES WILL STRUGGLE TO GET OUT OF THE 30S.

MCGUIRE

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

MCGUIRE

.PREV DISCUSSION... /ISSUED 959 AM CST SAT DEC 10 2011/

UPDATE...

WIDESPREAD DENSE FOG ACROSS SOUTHWEST KANSAS AND PORTIONS OF
WESTERN OKLAHOMA CONTINUES TO DRIFT NORTHEASTWARD IMPACTING
PORTIONS OF CENTRAL AND SOUTH CENTRAL KANSAS. ALTHOUGH CONTINUED
MIXING SHOULD RESULT IN A GRADUAL INCREASE IN VISIBILITIES/CEILINGS
THE FORECAST WAS ADJUSTED TO TO MAINTAIN AREAS OF FOG/CLOUDY
WORDING THROUGH THE MORNING HOURS.

MCGUIRE

PREV DISCUSSION... /ISSUED 525 AM CST SAT DEC 10 2011/

AVIATION...12Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
THE ONLY PERIOD OF CONCERN IS EARLY THIS MORNING WHEN PATCHY FOG MAY
REDUCE VSBYS TO 4-5SM TIL 14Z-15Z. SHOULD BE EXCELLENT FLYING WEATHER
THEREAFTER...HOWEVER SW WINDS WILL INCREASE TO ~13KTS/15MPH OVER ALL
5 TERMINALS ~15Z AS BROAD WRN PLAINS SFC TROF GRADUALLY ASSERTS
ITSELF.

PREV DISCUSSION... /ISSUED 258 AM CST SAT DEC 10 2011/

DISCUSSION...

MAIN FORECAST CHALLENGE WILL BE PRECIP CHANCES FOR NEXT WEEK.

SYNOPSIS:
UPPER TROUGH EXTENDS FROM THE EASTERN GREAT LAKES INTO THE LOWER
MISSISSIPPI VALLEY. AT THE SURFACE HIGH PRESSURE IS CENTERED OVER
THE OZARK REGION AND ENCOMPASSES ALL OF EASTERN KS AND OK. THE LOW
CLOUDS QUICKLY DISSIPATED AROUND 10PM WITH CLEAR SKIES REMAINING
OVER THE AREA. THE GOOD RADIATIONAL COOLING CONDITIONS HAVE RESULTED
IN SOME PATCHY FOG ACROSS PORTIONS OF THE AREA WITH WIDESPREAD DENSE
FOG NOT EXPECTED THIS MORNING.

TODAY-TONIGHT:
THE UPPER TROUGH TO OUR EAST WILL CONTINUE TO QUICKLY PUSH EAST WITH
THE SURFACE HIGH EXPECTED TO EXTEND FROM THE OHIO VALLEY INTO THE
ARKLATEX REGION BY LATE THIS AFTERNOON. THIS WILL FLIP OUR WINDS
AROUND TO THE SW PROVIDING A SLIGHT WARM-UP. WATER VAPOR IMAGERY IS
SHOWING A WEAK UPPER IMPULSE OVER EASTERN WY AND SLIDING SLOWLY
SOUTHEAST. THIS FEATURE IS EXPECTED TO SLIDE OVER WEST-CENTRAL KS
TONIGHT BUT DUE TO THE DRY AIRMASS IN PLACE NO PRECIP IS EXPECTED
WITH THIS FEATURE. THE MAIN IMPACT THIS WAVE WILL HAVE WILL BE TO
TIGHTEN-UP THE PRESSURE GRADIENT OVER THE AREA ALLOWING FOR STRONGER
SOUTH WINDS.

SUN-MON:
THE MAIN THEME THROUGH THESE PERIODS WILL BE INCREASING RETURN FLOW
AND ASSOCIATED MOISTURE. GUSTY SOUTH WINDS WILL BE IN PLACE ON SUN
WHICH WILL ALLOW LOW LEVEL MOISTURE TO RAPIDLY INCREASE. BOTH THE
GFS AND NAM AGREE ON LOW CLOUDS QUICKLY PUSHING INTO THE WESTERN HALF
OF THE FORECAST AREA BY SUN AFTERNOON WITH THESE LOW CIGS HERE TO
STAY. WENT AHEAD AND INSERTED SOME DRIZZLE AND LIGHT FOG FOR CENTRAL
KS ON SUN NIGHT. EVEN THOUGH MOISTURE QUICKLY INCREASES...LACK OF
DEEP LIFT WILL LIMIT CHANCES FOR MEASURABLE PRECIP WITH DRIZZLE THE
MAIN PRECIP MODE. IF WE WOULD HAVE A COLDER AIRMASS IN PLACE WE
WOULD BE LOOKING AT A CLASSIC FREEZING DRIZZLE SETUP. LUCKILY TEMPS
ARE EXPECTED TO REMAIN ABOVE FREEZING THROUGH THIS TIME PERIOD.

TUE-FRI:
THROUGH THIS TIME FRAME IS WHEN THE SHORT WAVE IS STILL EXPECTED TO
DIRECTLY IMPACT THE AREA. EVEN THOUGH THE GFS IS SLIGHTLY DEEPER AND
NOT AS POSITIVELY TILTED AS THE ECMWF...THEY AGREE MUCH BETTER ON THE
TIMING OF THIS FEATURE COMPARED TO LAST NIGHT`S RUNS. WILL START
PRECIP CHANCES ON TUE WITH CHANCES INCREASING FOR WED AS THE UPPER
WAVE KICKS OUT OF THE SOUTHERN ROCKIES AND INTO THE HIGH PLAINS.
THIS WAVE IS EXPECTED TO RAPIDLY LIFT OFF OT THE NORTHEAST ONCE IT
GETS OUT INTO THE PLAINS WITH THE PRECIP CHANCES COMING TO AN END BY
EARLY THU MORNING. ONCE AGAIN IT LOOKS LIKE THE TEMP PROFILE WILL
REMAIN WARM ENOUGH TO KEEP ALL OF THE PRECIP IN LIQUID FORM.

LAWSON

.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 40 26 48 35 / 0 0 10 10
HUTCHINSON 40 26 47 34 / 0 0 10 10
NEWTON 42 26 47 35 / 0 0 10 10
ELDORADO 43 27 48 35 / 0 0 10 10
WINFIELD-KWLD 40 27 49 35 / 0 0 10 10
RUSSELL 40 23 44 34 / 0 0 10 10
GREAT BEND 40 24 45 34 / 0 0 10 10
SALINA 44 25 47 35 / 0 0 10 10
MCPHERSON 43 26 47 34 / 0 0 10 10
COFFEYVILLE 45 27 49 33 / 0 0 10 10
CHANUTE 45 26 49 34 / 0 0 0 10
IOLA 44 26 48 34 / 0 0 0 10
PARSONS-KPPF 45 26 49 34 / 0 0 0 10

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

AREA FORECAST DISCUSSION

NWS TOPEKA KS

1152 AM CST SAT DEC 10 2011

...UPDATE TO AVIATION...

.DISCUSSION...

SHORT RANGE FORECAST (TODAY AND SUNDAY)...

MID-RANGE AND EXTENDED FORECAST (MONDAY THROUGH FRIDAY)...

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.

.AVIATION...

BOWEN

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

313 PM EST SAT DEC 10 2011

.SYNOPSIS...

12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW PROGRESSIVE WRN
RDG/ERN TROF PATTERN OVER NAMERICA. 12Z H85 TEMPS RANGE FM -18C AT
APX TO 7C AT GLASGOW MT. STRONG SFC-H85 SW FLOW OVER THE NRN PLAINS/
UPR MS RIVER VALLEY BTWN HI PRES IN THE OH VALLEY AND LO PRES NEAR
LK WINNIPEG IS CAUSING WAD AND ALLOWING THE UPR RDG TO BUILD TO THE
E PER 00Z-12Z 100-200M H3 HGT RISES OBSVD TO THE E OF THE UPR RDG
AXIS. THE BACKING LLVL FLOW TO SW OVER THE CWA HAS PUSHED THE SHSN
THAT WERE IMPACTING THE KEWEENAW AND AREAS E OF MUNISING OUT INTO
THE OPEN LK. THE STRONG WAD HAS ALSO CAUSED AN EXPANSIVE AREA OF MID
CLD STRETCHING FM LK WINNIPEG INTO THE UPR GRT LKS/UPR MS VALLEY
WELL APPROXIMATED BY THE HIER RH DEPICTED FM H8-6 ON THE 12Z INL
RAOB AND ON THE NAM 285K ISENTROPIC SFC. HOWEVER...DRY NATURE OF THE
LLVLS PER LARGE SFC-H85 DWPT DEPRESSIONS AND UPSTREAM 12Z RAOBS AS
WELL AS LACK OF ANY OTHER FORCING MECHANISM UNDER THE UPR HGT RISES
IS PREVENTING ANY PCPN EXCEPT OVER FAR NE MN. FARTHER TO THE W...THE
ADVECTION OF MUCH WARMER AND DRIER AIR SHOWN ON THE 12Z BISMARCK
RAOB IS PUSHING THE WRN EDGE OF THE MID CLD STEADILY TO THE E THRU
MN.
&&

.SHORT TERM DISCUSSION /TNGT AND SUN/...

MAIN FCST CONCERNS DURING THIS RELATIVELY QUIET PERIOD WL BE TEMPS
IN WAD PATTERN THAT WL DOMINATE.

TNGT...STRONG WARM/DRY ADVECTION WITH WSW H925-85 FLOW WL DISSIPATE
LINGERING LO/MID CLD SW-NE AS MODELS SHOW STEADILY RISING H85 TEMPS
AND LOWERING RH...INDICATING THE WAD IS BEING MANIFEST AS HORIZONTAL
ADVECTION/EROSION OF COLD AIR AND NOT UPWARD MOTION OVER THE COLD
DOME. IN FACT...NAM/GFS SHOW H85 TEMPS REACHING 7C AT IWD BY 12Z.
ANY PCPN WL BE OVER THE NE HALF OF LK SUP MAINLY THIS EVNG... AND
THIS WL DIMINISH WITH TIME. ALTHOUGH THE DEEPER COLD AIR WL BE
RETREATING...SUSPECT POCKETS OF NEAR SFC COLD AIR WL BE MORE
RESILIENT OVER THE INTERIOR. SO TENDED TOWARD THE LO END OF GUIDANCE
IN THESE AREAS. THE WARMEST LOCATIONS ARE LIKELY TO BE IN THE
DOWNSLOPE AREAS NEAR LK SUP.

SUN...THE CWA WL BE DOMINATED BY THE WARM...DRY WSW FLOW BTWN HI
PRES SINKING INTO THE OH VALLEY AND LO PRES CROSSING NW ONTARIO.
LOOKING UPSTREAM...SKIES ARE MOSUNNY AS THE DRY AIRMASS SHOWN ON THE
12Z BISMARCK RAOB IS DOMINATING. WITH H85 TEMPS FCST TO BE ABOUT
7C...EXPECT TEMPS TO RECOVER WELL ABV NORMAL. HOWEVER...EXACTLY HOW
HI TEMPS CAN RISE WL BE TRICKY WITH RESIDUAL ARCTIC AIR LIKELY TO BE
LINGERING NEAR THE SFC. CONSIDERING THE HI STABILITY SHOWN ON FCST
SDNGS AS WELL AS LO SUN ANGLE...TENDED TOWARD THE LOWER END OF
GUIDANCE. ONCE AGAIN...EXPECT THE HIEST TEMPS ARND 40 IN THE
DOWNSLOPE AREAS NEAR LK SUP WHERE ANY LINGERING NEAR SFC COLD AIR IS
MOST LIKELY TO BE ERODED.

.LONG TERM /00Z MONDAY THROUGH NEXT SATURDAY/...

A WEAK SFC TROUGH WILL EXTEND FROM THE CENTRAL PLAINS STATES THROUGH
PART OF THE CWA FROM LATE SUNDAY THROUGH TUESDAY. MODELS ARE IN
PRETTY GOOD AGREEMENT WITH THIS AND BRINGING AN UPPER SHORTWAVE OVER
THE CWA MONDAY. THE SHORTWAVE COMBINED WITH ISENTROPIC ASCENT WILL
BRING PERIODS OF PRECIP TO THE CWA EARLY MONDAY THROUGH
TUESDAY...WITH THE PRECIP TYPE BEING COMPLEX. THERMAL AND MOISTURE
PROFILES WILL BE THE COMPLICATING FACTOR...AND WILL LEAD TO CHANCES
FOR FREEZING DRIZZLE BEFORE SFC TEMPS WARM UP ON MONDAY...BECOMING
CHANCES FOR A RAIN AND SNOW MIX THROUGH TUESDAY THAT WILL BE MORE
DOMINATED BY SNOW OVER TIME AS COLDER AIR MOVES IN FROM N TO S. MID
LEVEL MOISTURE WILL BE SOMEWHAT LACKING...ESPECIALLY OVER THE SRN
CWA...WHICH FURTHER LOWERS CONFIDENCE ON PTYPE SINCE MOISTURE WILL
BE MINIMAL IN...ABOVE...AND BELOW THE DGZ.

OVERALL CONFIDENCE DECREASES STARTING WEDNESDAY AS MODELS WAIVER
WITH THE HANDLING OF THE NEXT SYSTEM. THE GEM AND ECMWF HAVE BETTER
RUN TO RUN CONTINUITY THAT THE GFS DURING THIS TIME PERIOD...BUT ARE
STILL NOT THAT GREAT. USED A MODEL BLEND FROM WEDNESDAY OUT AS
CONFIDENCE IN ANY MODEL OR SET OF MODELS IS JUST TOO LOW.

LARGE SCALE PATTERN WISE...MODELS SEEM TO HAVE THE SAME GENERAL
IDEA. A 500MB LOW WILL MOVE FROM THE ACTIC CIRCLE FROM WEDNESDAY TO
HUDSON BAY THURSDAY AS A SERIES OF UPPER LEVEL DISTURBANCES MOVE
INTO THE NWRN CONUS FROM THE NRN PACIFIC. THIS WILL KICK A DEEP
500MB LOW ALREADY IN PLACE OVER SRN CA INTO THE PLAINS WEDNESDAY
NIGHT. THE UPPER LOW WILL WEAKEN TO A WEAK TROUGH AND MOVE UP THE E
SIDE OF A NEW DEEP TROUGH OVER THE W CENTRAL CONUS...WITH THE
SHORTWAVE MOVING OVER THE CWA DURING THE LATTER HALF OF THURSDAY.
MODELS IN THE PAST WERE SHOWING THE UPPER SYSTEM MOVING OVER AS A
DEEPER CLOSED LOW...BUT HAVE BEEN TRENDING WEAKER AND IN MORE OF AN
OPEN WAVE ALOFT.

THIS WHOLE PATTERN WOULD RESULT IN MIXED PRECIP MOVING INTO THE CWA
ON WEDNESDAY AS A WEAK SHORTWAVE MOVE OVER WITH ISENTROPIC ASCENT
ALSO HELPING OUT. THEN AS THE UPPER TROUGH TROUGH MOVES THROUGH
THURSDAY...A CLOSED SFC LOW WILL DEVELOP AND MOVE OVER OR NEAR THE
CWA. THE ECMWF AND GEM BRING THE SFC LOW RIGHT ALONG THE SERN EDGE
OF THE CWA...WHILE THE GFS MOVES IT OVER FARTHER SE OVER CENTRAL
LOWER MI. GIVEN A MODEL BLEND...THE BEST CHANCES FOR PRECIP WILL BE
OVER THE SERN CWA...WHICH IS ALSO WHERE THE CONFIDENCE IN THE
FORECAST WITH THIS SYSTEM IS HIGHEST. PTYPE IS MORE IN
QUESTION...BUT WOULD LEAN TOWARD A RAIN/SNOW MIX OVER THE SERN CWA
AND MORE SNOW OVER THE NWRN CWA. THERE IS POTENTIAL FOR SIGNIFICANT
SNOWFALL ACCUMULATIONS SOMEWHERE IN THE REGION...BUT THAT IS HIGHLY
DEPENDENT ON THE TRACK OF THE SYSTEM. IF THE SYSTEM MOVES SOMEWHERE
BETWEEN THE TRACKS SHOWN BY THE GFS AND ECMWF...IT WOULD BE A
TYPICAL TRACK FOR HEAVY SNOW ACROSS PORTIONS OF THE CWA...BUT
CONFIDENCE IS WA TOO LOW TO PINPOINT THAT AT THIS TIME.

THE SFC LOW EXITS EAST AND HIGH PRESSURE MOVES IN FROM THE W FRIDAY
AND SATURDAY...AS 850MB TEMPS FALL TO AOB -15C. WITH W-NW
WINDS...LES WOULD APPEAR A LIKELY RESULT...BUT MOISTURE...WIND
DIRECTIONS AND OTHER FINICKY ENGREDIENTS WILL HAVE TO BE SORTED AS
TIME GOES ON.
&&

.AVIATION /FOR THE 18Z TAF ISSUANCE/...

ALTHOUGH THERE WL BE PLENTY OF MID CLD ARND THIS AFTN INTO THE EARLY
EVNG...EXPECT VFR CONDITIONS AT ALL 3 SITES THIS FCST PERIOD WITH
DRY LLVL SW FLOW DOMINATING. THERE WL BE SOME LLWS AT MAINLY IWD/SAW
TNGT WHERE THE WINDS WL BE STRONGEST AT THE TOP OF STABLE COLD AIR
NEAR THE SFC. DAYTIME HEATING/MIXING ON SUN WL DIMINISH THIS THREAT
BY NOON.
&&

.MARINE /FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE/...

EXPECT INCREASING WSW WINDS TO 30 KTS LATE TONIGHT AND SUN UNDER
SHARPENING PRES GRADIENT BETWEEN HI PRES IN THE OH RIVER VALLEY AND
LO PRES CROSSING ONTARIO. BEST CHANCE FOR MARGINAL GALES TO 35 KTS
WILL BE ON SUN IN THE SWATH OVER THE W BETWEEN ISLE ROYALE AND THE
KEWEENAW...WHERE TERRAIN FUNNELING CAN ENHANCE WSW WIND SPEEDS. BUT
GIVEN HI STABILITY...OPTED TO MAINTAIN JUST MENTION OF GALE FORCE
GUSTS ATTM. WITH A LO PRES TROF/WEAKER GRADIENT SINKING ACROSS LK
SUP ON MON/MON NIGHT...LOOK FOR WINDS TO DIMINISH AND SHIFT TO THE
N. LIGHT WINDS SHIFTING TO THE S WILL THEN BE THE RULE INTO WED AS A
HI PRES RIDGE SLIDES OVER THE LK AND TO THE E. ANOTHER LO PRES WILL
MOVE NE TOWARD THE UPPER LKS ON THU...BUT GALES DO NOT APPEAR LIKELY
ATTM.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

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

AREA FORECAST DISCUSSION

NWS KANSAS CITY/PLEASANT HILL MO

330 PM CST Sat Dec 10 2011

.DISCUSSION...

Brisk southwest winds coupled with abundant sunshine have allowed
afternoon temperatures to climb into the mid to upper 30s across
northeast Missouri to the middle 40s across eastern Kansas and
western Missouri. While gusty conditions are expected to subside this
evening, moderate southwesterly sfc flow is expected to persist
overnight as a sfc low slides across the northern tier of the country
while sfc ridging moves into the Ohio valley. Stubborn stratus has
been slow to erode across southwestern Kansas this afternoon with
models doing a poor job resolving the feature. Uncertainty remains
high as to whether additional stratus will develop overnight and
advect northeastward. There appears to be some support of this idea
from the latest RUC and VSREF outputs after 03-04z. Will hold off on
stratus mention at the moment although may have to be added by later
shifts should stratus development show signs of coming to fruition.

Southerly low level flow will be maintained tomorrow as the
aforementioned sfc low skirts across southern Canada. This coupled
with increasing thicknesses should yield temperatures climbing a few
degrees higher than seen today. By Sunday night, 35-40kt LLJ may
support a few showers across far northwest Missouri as isentropic
ascent increases across this area.

Vigorous upper level trough will begin translating across the
southwestern US during the beginning of the week spreading height
falls across the plains. This will maintain WAA regime Monday and
Tuesday keeping afternoon temperatures in the 40s to near 50
degrees. The amount of warming will likely be offset to some extent by
increasing cloud cover during this time frame. Guidance has come into
better agreement on a lead wave ejecting across the plains during the
day Tuesday bringing the first round of rain the region. Have
increase POPs to the high chance category during the day Tuesday with
likely wording for Tuesday night across portions of central Missouri.

The main upper system then moves into the plains and Midwest on
Wednesday keeping high rain chances in place through Wednesday night. In
addition, sufficient moisture and ascent should be in place for at
least an isolated chance of thunderstorms as well. This system slides
east of the area by Thursday with the next upper trough diving into
the desert southwest by Friday. Uncertainty increases thereafter and
have went with a dry forecast through the remainder of the forecast
to account.

DEROCHE

.AVIATION...

VFR conditions expected through this evening across all three taf
sites with clear skies and moderate southerly winds. Models continue
to suggest stratus/fog development across portions of central Kansas
by tomorrow morning. Condensation pressure deficits suggest this
activity to remain west of the terminals so will exclude from
mentioning in the taf. However, if this trends further east then a
mention may be needed in later taf issuances.

DEROCHE

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

WFO EAX

AREA FORECAST DISCUSSION

NWS WILMINGTON NC

1218 PM EST SAT DEC 10 2011

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM SATURDAY...LOW CLOUDS CONTINUE TO ERODE FROM WEST TO
EAST PRETTY MUCH ON SCHEDULE. TEMPERATURES ARE RISING INTO THE 52-54
RANGE WHICH MAKES OUR PREVIOUS HIGHS LOOK REASONABLE. WE DID
INCREASE WIND SPEEDS BY A COUPLE MPH...ESPECIALLY IN THE ILM
VICINITY...BASED ON LATEST OBSERVATIONS. PREVIOUS DISCUSSION FROM
930 AM FOLLOWS...

THE NORTHERN AND SOUTHERN BRANCHES OF THE JET STREAM ARE COMBINING
FORCES ACROSS THE EASTERN U.S. THIS MORNING AS A STRONG UPPER TROUGH
MOVES EAST ACROSS THE GREAT LAKES. A WEAKER SOUTHERN STREAM VORT
MOVING JUST AHEAD OF THE STRONG NORTHERN STREAM FEATURE IS CROSSING
THE CAROLINAS CURRENTLY...HELPING TO INDUCE A FEW LIGHT SPRINKLES
ACROSS THE EASTERN CAROLINAS. THESE SPRINKLES SHOULD LARGELY
DISSIPATE AND/OR MOVE OFF THE COAST WITHIN THE NEXT HOUR AS THE
TROUGH EXITS TO THE EAST.

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 18Z...HIGH CONFIDENCE IN VFR THROUGH THE VALID PERIOD.

MID LEVEL TROUGH AS EVIDENCED BY SIGNIFICANT WIND SHIFT AT 850 MB
WILL CONTINUE TO ROTATE EAST ACROSS THE AREA THROUGH THIS EVE. MUCH
DRIER AIR WORKS IN BEHIND THIS TROUGH...SO BY TONIGHT ALL TERMINALS
WILL EXPERIENCE SKC. NORTH WINDS OF 9-12 KTS WILL DECREASE AFTER
SUNSET...BUT TIGHTENED PG AHEAD OF ADVANCING HIGH PRESSURE WILL KEEP
THEM FROM DECOUPLING. THIS SUGGESTS WINDS REMAINING 4-8 KTS
OVERNIGHT.

AFTER SUNRISE E/NE WINDS WILL INCREASE...GUSTING UP TO 20 KTS BY
LATE MORNING. THIS WILL ADVECT MOISTURE INTO THE COLUMN...WHICH MAY
DEVELOP INTO A 5-6 KFT CLOUD LAYER IF FORECAST SOUNDINGS ARE
CORRECT. HOWEVER...SIGNIFICANT DRY AIR JUST ABOVE THE INVERSION WILL
LIKELY MIX OUT MUCH OF THE MOISTURE SO HAVE ONLY SCT AT THE COAST
WITH SKC CONTINUING INLAND THROUGH 18Z SUNDAY.

EXTENDED OUTLOOK...LOW CONFIDENCE IN SHOWERS AND STRATUS SUNDAY
NIGHT INTO MONDAY MORNING...ESPECIALLY NEAR THE COAST. VFR MONDAY
THROUGH WEDNESDAY. LOW CONFIDENCE IN FOG THURSDAY MORNING.

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM SATURDAY...WINDS AND SEAS CONTINUE TO SLOWLY INCREASE
AS COLD AIR POURS OFFSHORE AND THE PRESSURE GRADIENT TIGHTENS WITH
THE APPROACH OF THE ARCTIC HIGH. ALL FORECAST ELEMENTS LOOK TO BE ON
TRACK AND NO CHANGES WERE NECESSARY TO THE FORECAST. PREVIOUS
DISCUSSION FROM 930 AM FOLLOWS...

COLD AIR IS BUILDING INTO THE AREA THIS MORNING AS ARCTIC HIGH
PRESSURE OVER MISSOURI/SOUTHERN ILLINOIS BUILDS EAST. THE PRESSURE
GRADIENT WILL REALLY INCREASE TONIGHT AS THE HIGH MOVES INTO THE
OHIO VALLEY...CAUSING OUR WIND SPEEDS TO INCREASE TO A SOLID 25 KT
AWAY FROM SHORE WITH HIGHER GUSTS. UNTIL THEN...NORTH WINDS 15-20 KT
ARE EXPECTED DURING THE DAYLIGHT HOURS TODAY...WITH A SHORT PERIOD
WIND CHOP GRADUALLY BUILDING THROUGH THE AFTERNOON. SPECTRAL WAVE
PLOTS FROM FRYING PAN SHOALS SHOW THAT THE SHORT PERIOD WAVES NOW
"OUTWEIGH" THE MODEST SOUTHEAST SWELL WE HAVE BEEN RECEIVING SINCE
YESTERDAY...MAKING CONDITIONS QUITE ROUGH ALREADY FOR MARINERS. THE
SMALL CRAFT ADVISORY REMAINS IN EFFECT BEGINNING AT 4 PM TODAY.

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST
SUNDAY FOR AMZ250-252-254-256.

SYNOPSIS...31
NEAR TERM...TRA
SHORT TERM...31
LONG TERM...31
AVIATION...JDW

AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

449 PM EST SAT DEC 10 2011

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
WIDESPREAD BKN /ALBEIT RATHER SHALLOW/ STRATO CU PRODUCING SCATTERED
FLURRIES SEEN ACROSS THE NRN HALF OF PENN LATE THIS MORNING VIA A
FAIRLY WELL ALIGNED 290 MEAN BLYR FLOW.

THE SCENT VALLEYS WILL STAY MOSTLY SUNNY THIS AFTERNOON AS THE
COOLEST 850-500 MB TEMPS /AND BEST FETCH OF MOISTURE OFF LAKE ERIE/
SLIDE EAST ACROSS NRN PENN AND NEW YORK STATE.

.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
LAKE EFFECT SHSN SHOULD DIMINISH AND HALT BEFORE A POSSIBLE RE-
DEVELOPMENT THIS EVENING/EARLY TONIGHT. THIS WILL BE DUE TO THE
BACKING FLOW AT THE LOW LEVELS WHILE 8H FLOW STAYS WNW FOR MOST OF
THE NIGHT. THIS IS KIND OF TYPICAL...AS PAST EXPERIENCE INDICATES
THAT WE OFTEN GET A LAST GASP BAND AS THE WAA BEGINS AND PINCHES
THE LINGERING MOISTURE IN A NARROW BAND OF CONVERGENCE LIFTING
NEWRD. ANY SHSN TONIGHT SHOULD BE NORTH OF ROUTE 6. THE CLEARING
THAT BECOMES NEARLY COMPLETE BY SUNRISE SUN AM WILL HELP THE TEMPS
DROP INTO THE TEENS EVERYWHERE ACROSS THE CWA. THE TYPICAL COLD
AIR DRAINAGE SITES LIKE KSEG/KTHV COULD BE 2-5F LOWER THAN
NEIGHBORING SITES.

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
NRN STREAM FRONT DROPS DOWN THROUGH NY STATE ON TUES NIGHT...AND
MAY MAKE IT INTO PA. BUT...THE HIGH WILL BE SITTING OVER THE
ENTIRE EASTERN SIDE OF THE CONTINENT AND SHOULD FEND IT OFF.
NO REAL MOISTURE WITH THAT BACKDOOR FRONT ANYWAY. WAA AND
INCREASING GULF MOISTURE TO OUR WEST WILL BRING AT LEAST SOME
LOWERED CLOUDS OVERHEAD TUES NIGHT/WED AS WARM FRONT WORKS TO THE
NORTH THROUGH THE OH VALLEY AND INTO THE LOWER GREAT LAKES. SO WE
SHOULD SEE SOME CHC OF A BRIEF SHOWER FROM TUES NIGHT INTO
WED...BUT BULK OF THE TIME WILL BE DRY.

.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
HIGH PRESSURE OVER THE OHIO VALLEY WILL BUILD INTO CENTRAL PA
OVERNIGHT...BRINGING DIMINISHING WINDS AND CLEAR SKIES TO MOST OF
THE AREA. A WEST FLOW OFF OF LK ERIE COULD PRODUCE MVFR CIGS AND A
FEW FLURRIES AT BFD THROUGH LATE EVENING. HOWEVER...EVEN THERE
SKIES SHOULD CLEAR BY 06Z...AS FLOW SHIFTS TO THE WSW.

A HIGH CONFIDENCE FORECAST OF VFR AND LIGHT WINDS CONTINUES
THROUGH SUNDAY...AS HIGH PRESSURE PASSES OVER THE STATE.

OUTLOOK...
SUN-TUE...NO SIG WX/VFR.
WED...CHC OF A SHOWER...VFR/MVFR.

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT/CERU
SHORT TERM...LAMBERT/CERU
LONG TERM...LAMBERT
AVIATION...FITZGERALD/CERU

AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

232 PM EST SAT DEC 10 2011

THE SCENT VALLEYS WILL STAY MOSTLY SUNNY THIS AFTERNOON AS THE
COOLEST 850-500 MB TEMPS /AND BEST FETCH OF MOISTURE OFF LAKE ERIE/
SLIDE EAST ACROSS NRN PENN AND NEW YORK STATE.

.SHORT TERM /7 PM THIS EVENING THROUGH TUESDAY/...
LAKE EFFECT SHSN SHOULD DIMINISH AND HALT BEFORE A POSSIBLE RE-
DEVELOPMENT THIS EVENING/EARLY TONIGHT. THIS WILL BE DUE TO THE
BACKING FLOW AT THE LOW LEVELS WHILE 8H FLOW STAYS WNW FOR MOST OF
THE NIGHT. THIS IS KIND OF TYPICAL...AS PAST EXPERIENCE INDICATES
THAT WE OFTEN GET A LAST GASP BAND AS THE WAA BEGINS AND PINCHES
THE LINGERING MOISTURE IN A NARROW BAND OF CONVERGENCE LIFTING
NEWRD. ANY SHSN TONIGHT SHOULD BE NORTH OF ROUTE 6. THE CLEARING
THAT BECOMES NEARLY COMPLETE BY SUNRISE SUN AM WILL HELP THE TEMPS
DROP INTO THE TEENS EVERYWHERE ACROSS THE CWA. THE TYPICAL COLD
AIR DRAINAGE SITES LIKE KSEG/KTHV COULD BE 2-5F LOWER THAN
NEIGHBORING SITES.

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
12Z TAFS ADJUSTED FOR CURRENT CONDITIONS.

HIGH PRESSURE WILL BUILD OVER PA LATE TODAY INTO SUNDAY. VFR
CONDITIONS WILL THEN PREVAIL THROUGH EARLY NEXT WEEK.

OUTLOOK...
SUN-TUE...NO SIG WX/VFR.
WED...CHC OF A SHOWER...VFR/MVFR.

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...DANGELO/CERU
LONG TERM...DANGELO/MARTIN
AVIATION...CERU/MARTIN

AREA FORECAST DISCUSSION

NWS LA CROSSE WI

1158 AM CST SAT DEC 10 2011

.SHORT TERM...
955 AM CST SAT DEC 10 2011

.LONG TERM...TUESDAY THROUGH FRIDAY
300 AM CST SAT DEC 10 2011

.AVIATION...THROUGH 18Z SUNDAY
1158 AM CST SAT DEC 10 2011

CURRENTLY KEEPING A WATCH ON A MVFR STRATUS DECK MOVING EAST
ACROSS NORTHEAST IA/SOUTHEAST MN. NAM12/RUC MODELED RH FIELDS HAVE A
GOOD HANDLE ON THIS STRATUS DECK AND HAVE IT ADVECTING EAST OF THE
AREA BY LATER THIS AFTERNOON. OTHERWISE...A BAND OF ALTOCUMULUS
WITH CIGS AOA 7KFT WAS MOVING EAST ACROSS NORTHER/CENTRAL WI.
MODELS ALSO HAVE THIS PUSHING EAST OF THE AREA BY LATER THIS
AFTERNOON. WILL THEN SEE A WARM FRONT PUSH EAST ACROSS THE AREA
TONIGHT WITH WINDS STAYING OUT OF THE SOUTH/SOUTHWEST AROUND 15KT
AT KRST...AND AROUND 10KT DOWN IN THE MISSISSIPPI RIVER VALLEY AT
KLSE. THIS RAISES ANOTHER CONCERN AT KLSE ABOUT LOW LEVEL WIND
SHEAR AS WINDS AOA 1000 FEET ARE DEPICTED BY BUFKIT MODEL
SOUNDINGS TO BE AROUND 30-35KT FROM THE WEST/SOUTHWEST. ALTHOUGH
TECHNICALLY NOT ENOUGH CRITERIA FOR WIND SHEAR...PILOTS STILL MAY
EXPERIENCE SOME BUMPINESS ON FINAL APPROACH OR TAKING OFF FROM
KLSE. OTHERWISE...LOOKS LIKE VFR CONDITIONS WILL PREVAIL OVERNIGHT
THROUGH SUNDAY MORNING. LOOKING FURTHER...APPEARS IFR/FREEZING
DRIZZLE THREAT IS INCREASING FOR SUNDAY NIGHT AFTER MIDNIGHT.

.ARX WATCHES/WARNINGS/ADVISORIES...
300 AM CST SAT DEC 10 2011

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

SHORT TERM...DAS
LONG TERM....RABERDING
AVIATION...DAS