Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/06/13
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
932 AM MST FRI JAN 4 2013
.UPDATE...
&&
.SHORT TERM...CURRENT FORECASTS STILL ON TRACK. DRY AND WEAK
NORTHEAST FLOW ALOFT TO PREVAIL ACROSS COLORADO WITH A SLIGHT
WARMUP. HOWEVER...PERSISTANT INVERSIONS WILL KEEP COLD AIR
TRAPPED IN THE MOUNTAIN VALLEYS AND LOW LYING AREAS ACROSS PLAINS.
ELSEWHERE...TEMPERATURES TO WARM TO NEAR SEASONAL NORMALS. CURRENT
TEMP GRIDS LOOK REASONABLE. WINDS TO BE GENERALLY LIGHT AS WEAK
SURFACE GRADIENT PREVAILS.
.AVIATION...CURRENT TAF TRENDS LOOK REASONABLE. LATEST HRRR AND
RAP CONTINUE TO SHOW LIGHT EASTERLY WINDS THROUGH THE AFTERNOON
WITH DRAINAGE FOR THE EVENING. VFR TO CONTINUE WITH UNLIMITED
CEILINGS.
&&
.PREV DISCUSSION... /ISSUED 317 AM MST FRI JAN 4 2013/
SHORT TERM...AN UPPER LEVEL RIDGE AXIS TO THE NORTH OF COLORADO
COUPLED WITH A CLOSED LOW MOVING ACROSS CENTRAL NEW MEXICO WILL
ALLOW FOR A DRY AND RELATIVELY WEAK NORTHEASTERLY FLOW OVER THE
CWFA. WEAK SURFACE LOW PRESSURE WILL STRETCH FM NORTH TO SOUTH
ACROSS THE EASTERN PLAINS WITH GENERALLY WEAK GRADIENT WINDS.
TEMPERATURES WILL BE NEAR SEASONAL NORMALS FOR DENVER.
LONG TERM...UPPER LEVEL RIDGE WILL BE OVER THE GREAT BASIN SATURDAY
AND THEN SHIFT EAST ACROSS COLORADO SUNDAY AS AN UPPER LEVEL TROUGH
MOVES ONTO THE WEST COAST. LARGE DIFFERENCES EXIST BETWEEN THE
MODELS ON HOW THE UPPER LEVEL TROUGH WILL EVOLVE AND WHERE IT WILL
TRACK. THE GFS AND NAM SHOW THIS THROUGH WILL MOVE ACROSS COLORADO
IN PIECES WITH THE FIRST SHORT WAVE MOVING ACROSS SUNDAY NIGHT. THE
MAIN TROUGH WILL LAG BEHIND IT ON MONDAY NIGHT. THE ECMWF AND CMC
INDICATE THIS TROUGH WILL CLOSE OFF AND DIVE SOUTH INTO NORTHERN
MEXICO. THE LOW WILL THEN SLOWLY TRACK EAST ACROSS NORTHERN MEXICO
AND INTO TEXAS WEDNESDAY. EVEN IF THE GFS AND NAM ARE CORRECT...THEY
INDICATE A DRY DOWNSLOPE FLOW ACROSS THE FRONT RANGE. WILL HAVE LOW
POPS FOR THE MOUNTAINS MONDAY AND TUESDAY IN CASE THE GFS AND NAM
SOLUTION PANS OUT. TEMPERATURES WILL BE NEAR TO SLIGHTLY BELOW
NORMAL THIS WEEKEND AND EARLY NEXT WEEK.
FOR WEDNESDAY AND THURSDAY...MODELS COME BACK INTO BETTER AGREEMENT
OVER THE CENTRAL ROCKIES. AN UPPER LEVEL TROUGH WILL BE OVER THE
PACIFIC NORTHWEST WEDNESDAY AND THEN DIVE SOUTHEAST...ENDING UP OVER
THE GREAT BASIN THURSDAY. THIS WILL PRODUCE A WESTERLY FLOW ALOFT
WEDNESDAY AND SOUTHWESTERLY THURSDAY OVER COLORADO. EXPECT DRY
CONDITIONS AND NEAR NORMAL CONDITIONS TO PREVAIL. MOISTURE WILL
INCREASE AS THIS TROUGH NEARS ON THURSDAY...SO WILL HAVE LOW POPS
FOR THURSDAY. BETTER CHANCE FOR SNOW WILL COME FRIDAY AS THE TROUGH
MOVES OVER COLORADO.
AVIATION...VFR CONDITIONS OVER THE NEXT 24+ HOURS. SURFACE WINDS
WILL GENERALLY REMAIN SOUTHWESTERLY...STRONGEST UNTIL AROUND 15Z
THEN WEAKENING THIS AFTN...THEN INCREASING AGAIN THIS EVENING IN
RESPONSE TO THE DIURNAL DRAINAGE.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....MEIER
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
556 AM EST FRI JAN 4 2013
.SYNOPSIS...
HIGH PRESSURE BUILDS TO OUR SOUTH THROUGH SATURDAY, WHILE A WEAK
BACKDOOR COLD FRONT APPROACHES THE AREA FROM THE NORTH SATURDAY, BUT
LIKELY DOES NOT MAKE IT ACROSS THE AREA. AN AREA OF LOW PRESSURE
MOVES OUT OF THE GREAT LAKES REGION AND TOWARD OUR AREA SUNDAY,
BRINGING A WEAK FRONTAL BOUNDARY WITH IT. HIGH PRESSURE REINFORCES
ITSELF ACROSS THE EAST COAST EARLY NEXT WEEK, BEFORE PUSHING
OFFSHORE BY THE MIDDLE OF THE WEEK. ANOTHER LOW PRESSURE AND
ASSOCIATED FRONTAL BOUNDARY COULD AFFECT THE AREA DURING THE MIDDLE
TO LATTER PART OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE LOW LEVEL CLOUD SURGE HAS JUST ABOUT COMPLETED THE TRIP TO THE
NEW JERSEY SHORE...SO HOW THE CLOUD COVER CHANGES WITH TIME WILL
BE THE FORECAST PROBLEM OF THE DAY. THERE ARE SOME BREAKS IN THE
CLOUDS STARTING TO SHOW UP IN THE LEHIGH VALLEY...AND THE LATEST
RAP MODEL SUGGESTS THAT THIS HOLE WILL OPEN UP AND ALLOW MUCH OF
THE AREA TO BREAK OUT THIS MORNING.
HOWEVER...THE LATEST RAP SUGGESTED THIS WOULD OCCUR STARTING LAST
HOUR...SO JUST HOW THIS BREAKS UP MAY HAVE MORE TO DO WITH TERRAIN
(DOWNSLOPING) THAN ANY OTHER PROCESS. THE BREAKS SHOULD CONTINUE
ACROSS SOUTHEAST PENNSYLVANIA...NORTHERN DELAWARE THIS MORNING...
AS THEY WORK INTO CENTRAL AND SOUTHERN NEW JERSEY. THE FEEBLE
EARLY JANUARY SUN PROBABLY DOES NOT HELP MATTERS...AND MOST OF THE
CLEARING WILL HAVE TO OCCUR WITH MIXING DRIER AIR FROM ABOVE. THIS
PROBABLY DOES NOT OCCUR UNTIL MID TO LATE MORNING.
FOR THE SOUTHERN POCONOS AND NORTHWEST NEW JERSEY...THE PROCESS
COULD TAKE A LITTLE LONGER...BUT THIS WAS HINTED AT IN OTHER NEAR
TERM MODELS. NOT MUCH CHANGE TO THE SKY FORECAST IS ANTICIPATED
WITH THE UPDATE.
THE RADAR SIGNATURE FOR FLURRIES HAS GOTTEN BETTER OVER THE SOUTHERN
POCONOS AND NORTHWEST NEW JERSEY EARLY THIS MORNING. THIS MAY
NECESSITATE THE INCLUSION OF FLURRIES INTO THE MORNING HOURS AS THE
UPSLOPE FLOW COINCIDES WITH THE DEEPER BOUNDARY LAYER MOISTURE. AS
THE MOISTURE DRIES OUT...THE THREAT FOR FLURRIES SHOULD DIMINISH.
THE CLOUD COVER ACROSS NORTHWEST ZONES WILL CONTINUE TO BE A
FORECAST CHALLENGE TODAY. THE 0000 UTC NAM MAY BE TOO PESSIMISTIC
WITH ITS BOUNDARY LAYER MOISTURE (UNLESS MOISTURE FROM THE LAKES
BECOMES ENTRAINED). IT LOOKS LIKE THE INVERSION BREAKS BY
AFTERNOON...AND SKY COVER SHOULD DIMINISH. ELSEWHERE...MOISTURE MAY
POOL UNDER THE SHALLOWER INVERSION IN PLACE...BUT THIS SHOULD NOT BE
ENOUGH FOR MORE CLOUDINESS THAN PARTLY SUNNY WOULD COVER.
THE PRESSURE GRADIENT INCREASES DURING THE DAY...AS 925 MB WINDS
INCREASE. MODE SOUNDINGS SUGGEST THAT 35 KNOTS OF WIND COULD BE
AVAILABLE AT THE TOP OF THE INVERSION DURING THE AFTERNOON...AND
THIS COULD TRANSLATE TO 35 TO 40 MPH WINDS IN THE TERRAIN.
ELSEWHERE...THE AMOUNT OF MOMENTUM AT THE TOP OF THE INVERSION DOES
NOT APPEAR TO SUPPORT WIND ADVISORY LEVEL GUSTS. NOR DOES THE
PRESSURE RISES THIS AFTERNOON AND EVENING (WHICH MAXIMIZE OVER
UPSTATE NEW YORK AND NEW ENGLAND). THUS...NO WIND HEADLINES ARE
EXPECTED TODAY.
THE MOS BLEND SEEMED TO CAPTURE HIGH TEMPERATURES WELL THURSDAY.
SINCE THE COLUMN IS ABOUT THE SAME WITH REGARD TO TEMPERATURE AS
THURSDAY...HIGHS TODAY SHOULD BE FAIRLY CLOSE. WITH THIS IN MIND...
HIGHS WERE BASED ON THE SLIGHTLY COOLER NAM MOS NUMBERS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
THE WIND MAY BE THE TRICKIEST PART OF THE FORECAST FOR TONIGHT. THE
CORE OF THE 925 MB WINDS SHOULD OCCUR OVER CENTRAL AND SOUTHERN
AREAS BETWEEN 0000 UTC AND 0600 UTC SATURDAY. SHORT TERM MODELS ARE
SHOWING 35 TO 45 KNOTS OF WIND AT THIS LEVEL...WITH THE 0000 UTC NAM
THE STRONGEST OF THE MODEL SPREAD. MODEL SOUNDINGS IN THE
ABOVEMENTIONED AREA SHOW THAT THE MOMENTUM STAYS ABOVE THE
INVERSION...WHICH LOWERS WITH THE LOSS OF DAYTIME HEATING. WHILE IT
IS POSSIBLE THAT THE HIGHER TERRAIN COULD CONTINUE TO SEE WIND GUSTS
OVER 35 MPH TONIGHT....ELSEWHERE GUSTS SHOULD DIMINISH IN THE
EVENING.
THE BOUNDARY LAYER MOISTURE COULD INCREASE AGAIN ACROSS NORTHERN
ZONES...AS SHORT TERM MODELS ARE SHOWING THIS TREND. MAINLY CLEAR
SKIES ARE EXPECTED ELSEWHERE...AS THE MID LEVEL FLOW QUICKLY BECOMES
ZONAL. THERE COULD BE ENOUGH GRADIENT TONIGHT TO MITIGATE THE
POTENTIAL FOR RADIATIONAL COOLING...ESPECIALLY IN URBAN AREA AND OF
COURSE THE HIGHER TERRAIN. WITH THIS IN MIND...LOWS WERE GENERALLY
BASED ON THE MOS BLEND.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
A WEAK BACKDOOR COLD FRONT IS EXPECTED TO APPROACH THE AREA FROM THE
NORTH ON SATURDAY, BUT WILL LIKELY NOT MAKE IT ALL THE WAY INTO OUR
AREA AS HIGH PRESSURE BUILDS TO OUR SOUTH. WITH SLIGHT RIDGING ALOFT
ACROSS THE AREA SATURDAY AND HIGH PRESSURE AT THE SURFACE TO OUR
SOUTH, WE EXPECT SATURDAY TO BE PRECIPITATION FREE. AS WE MOVE
INTO SATURDAY NIGHT, MODELS CONTINUE TO INDICATE A SHORTWAVE
APPROACHING FROM THE SOUTHWEST. THERE IS SOME MOISTURE ASSOCIATE
WITH THE SHORT WAVE, SO WE COULD HAVE SOME SHOWER ACTIVITY MOVE ACROSS
THE AREA. TEMPERATURES SHOULD BE COLD ENOUGH FOR ANY PRECIPITATION
TO FALL AS SNOW. QPF AMOUNTS ARE GENERALLY LIGHT, SO WE ARE NOT
ANTICIPATING SIGNIFICANT ACCUMULATIONS.
ON SUNDAY, AN AREA OF LOW PRESSURE IS EXPECTED TO MOVE OUT OF THE
GREAT LAKES AND INTO NEW ENGLAND WHILE A SHORT WAVE MOVES THROUGH
THE AREA. THE BEST CHANCE OF ANY SHOWER ACTIVITY IS ACROSS OUR
NORTHWESTERN ZONES WHERE THE HIGHEST MOISTURE CONTENT IS
AVAILABLE. ANOTHER SHORT WAVE IS EXPECTED OVERNIGHT SUNDAY WHICH
COULD HELP LEAD TO ADDITIONAL SHOWER ACTIVITY, MAINLY ACROSS THE
NORTHERN HALF OF THE AREA. TEMPERATURES SUNDAY ARE EXPECTED TO RISE
ABOVE NORMAL AS A WARMING TREND BEGINS.
HIGH PRESSURE IS EXPECTED TO BUILD ACROSS THE EAST COAST MONDAY INTO
TUESDAY, WHILE RIDGING ALOFT TAKES PLACE AS WELL. THIS WILL ALLOW
TEMPERATURES TO REMAIN ABOVE NORMAL AND KEEP THE WEATHER DRY FOR THE
EARLY PART OF THE WEEK.
MODEL GUIDANCE BEGINS TO DIVERGE BY MID WEEK IN REGARDS TO THE NEXT
STORM SYSTEM. THE GFS IS THE FASTEST WITH THE NEXT STORM SYSTEM,
BRINGING IT INTO THE AREA AS EARLY AS WEDNESDAY AFTERNOON/EVENING.
THE ECMWF IS THE SLOWEST BRINGING THE SYSTEM INTO THE AREA THURSDAY
AFTERNOON/EVENING. THE CANADIAN WAS NEARLY RIGHT BETWEEN THE TWO AT
THE END OF ITS FORECAST CYCLE, SO WE TOOK A COMPROMISE BETWEEN THE GFS
AND ECMWF, BUT ONLY INTRODUCED A SLIGHT CHANCE OF PRECIP WEDNESDAY
NIGHT INTO THURSDAY. FOR MOST OF THE AREA, TEMPERATURES ARE
EXPECTED TO BE WARM ENOUGH TO KEEP ANY PRECIPITATION LIQUID, BUT
AREA FURTHER NORTH AND WEST COULD SEE SOME WINTRY PRECIP. AS WE
GET CLOSER, DETAILS WILL BECOME BETTER DEFINED. TEMPERATURES FOR
THE MIDDLE TO THE END OF THE WEEK ARE EXPECTED TO REMAIN ABOVE
NORMAL, WITH SOME AREA POSSIBLY RISING 1O TO 15 DEGREES ABOVE
NORMAL.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THE VFR CEILINGS (WITH BASES NEAR 4000 FEET) PROBABLY REMAIN IN
PLACE THROUGH 1500 UTC FOR MOST PLACES OUTSIDE OF THE TERRAIN
(WHERE IS LASTS EVEN LONGER). THE UPDATED TERMINAL FORECASTS WILL
INDICATE THIS...AND CONDITIONS SHOULD IMPROVE AFTER 1500 UTC.
RECENT AMDAR SOUNDINGS SUGGEST THAT THE CEILINGS WILL REMAIN
VFR...WITH JUST A LOW PROBABILITY OF MVFR CEILINGS THROUGH 1500
UTC.
AFTER THE CLOUDS BREAK LATER THIS MORNING...SCATTERED CLOUDS ARE
EXPECTED TODAY...WITH BASES CLOSE TO 3500 FEET. THERE IS A LOW
PROBABILITY THAT KABE AND KRDG COULD SEE CEILINGS NEAR 3000 FEET
FOR A TIME BETWEEN 1600 AND 2100 UTC. HOWEVER...THE PROBABILITY IS
NOT HIGH ENOUGH TO INCLUDE IN THE UPDATED FORECASTS. WEST WINDS
WILL BECOME GUSTY AFTER 1400 OR 1500 UTC...WITH MOST LOCATIONS
SEEING GUSTS REACH 24 TO 27 KNOTS THROUGH SUNSET.
VFR CONDITIONS ARE EXPECTED TONIGHT. THE SCATTERED CLOUDS NEAR 3500
FEET SHOULD DISSIPATE DURING THE EVENING. THE GUSTINESS SHOULD DROP
OFF BY 0100 UTC SATURDAY...THROUGH THE KPHL METRO AIRPORTS COULD
HANG ONTO THE GUSTINESS A BIT LONGER.
OUTLOOK...
SATURDAY-TUESDAY...MAINLY VFR. SNOW SHOWERS/FLURRIES POSSIBLE
SATURDAY NIGHT-SUNDAY NIGHT...ESPECIALLY NORTH AND WEST OF THE
ILG-PHL-PNE-TTN TAFS.
&&
.MARINE...
THE PRESSURE GRADIENT IS SUPPORTING SMALL CRAFT WIND GUSTS ALONG
SOME OCEAN LOCATIONS...BUT NOT OTHERS YET. THE GRADIENT HAS NOT YET
TIGHTENED ENOUGH TO SUPPORT SMALL CRAFT WINDS ON THE UPPER DELAWARE
BAY...AND IT IS GETTING CLOSE ON THE LOWER BAY. AS THE PRESSURE
GRADIENT TIGHTENS DURING THE EARLY MORNING HOURS...ALL WATERS SHOULD
BE NEAR OR ABOVE SMALL CRAFT WITH REGARD TO WIND GUSTS.
THE GRADIENT LOOKS TO SUPPORT SMALL CRAFT WINDS TODAY ON ALL
WATERS...THOUGH IT MAY BE MORE SPOTTY ON THE UPPER DELAWARE BAY. IT
IS POSSIBLE THAT A WEAKNESS IN THE GRADIENT EARLY THIS AFTERNOON
COULD ALLOW GUSTS ON DELAWARE BAY TO DROP BELOW SMALL CRAFT LEVELS.
THIS SHOULD BE TEMPORARY AND LITTLE CHANGE IN FORECAST PHILOSOPHY
FOR TODAY.
SHORT TERM MODELS ARE SHOWING WEST TO NORTHWEST WINDS AT 925 MB
INCREASING TO NEAR 40 KNOTS BEFORE 0000 UTC SATURDAY. MODEL
SOUNDINGS SUGGEST THAT THE MOMENTUM STAYS ABOVE THE INVERSION OVER
THE WATERS INTO THE EARLY EVENING HOURS. WHILE THERE COULD BE SOME
GUSTS TO NEAR 30 KNOTS TOWARD EVENING...GALE FORCE WINDS GUSTS DO
NOT LOOK LIKELY TODAY.
THE FORECAST PROBLEM FOR TODAY IS WHETHER THERE WILL BE ENOUGH GALE
FORCE WIND GUSTS TO JUSTIFY A GALE WARNING. THE CORE OF THE
STRONGEST WEST WINDS AT 925 MB CROSS THE CENTRAL WATERS BETWEEN 0300
UTC AND 0900 UTC SATURDAY...MAXIMIZING AROUND 0600 UTC. TYPICALLY 45
KNOTS AT 925 MB WOULD SUGGEST GALE FORCE GUSTS. MODEL SOUNDINGS
SUGGEST THAT THE CORE OF THE STRONGEST WINDS REMAINING ABOVE THE
INVERSION FOR THE CENTRAL AND NORTHERN OCEAN WATERS.
WHILE IT WILL BE CLOSE...WE WILL HOLD OFF ON A GALE WARNING FOR NOW.
IF THE 0600 UTC MODEL SUITE IS STRONGER WITH THE CORE OF THE WINDS
(AND MODEL SOUNDINGS ARE MORE GENEROUS WITH MOMENTUM TRANSFER)...IT
IS POSSIBLE A GALE WARNING COULD BE NEEDED LATER THIS MORNING. THE
MOST LIKELY CANDIDATES FOR A GALE WARNING WOULD BE THE NORTHERNMOST
OCEAN ZONE (OR TWO).
IN ANY EVENT...THE GALE THREAT SHOULD DIMINISH ACROSS THE NORTHERN
OCEAN AFTER 0900 UTC. ELSEWHERE...STRONG SMALL CRAFT WINDS ARE
EXPECTED THROUGH THE OVERNIGHT.
OUTLOOK...
SMALL CRAFT ADVISORY CONDITIONS COULD LAST THROUGH MIDDAY SATURDAY,
SO THE ADVISORY WAS EXTENDED UNTIL NOON SATURDAY. WINDS ARE EXPECTED
TO REMAIN BELOW ADVISORY LEVELS THE REST OF THE DAY SATURDAY INTO
SATURDAY NIGHT AS HIGH PRESSURE BUILDS TO OUR SOUTH. AS LOW PRESSURE
MOVES OUT OF THE GREAT LAKES INTO NEW ENGLAND SUNDAY, A COLD FRONT
WILL SWEEP THROUGH OUR AREA. WINDS BEHIND THIS SYSTEM COULD REACH
ADVISORY LEVELS SUNDAY NIGHT INTO EARLY MONDAY. WINDS ARE
EXPECTED TO DROP BACK BELOW ADVISORY LEVELS AS HIGH PRESSURE
REINFORCES ITSELF ACROSS THE EAST COAST LATE MONDAY INTO TUESDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL NOON EST SATURDAY FOR ANZ430-431-
450>455.
&&
$$
SYNOPSIS...ROBERTSON
NEAR TERM...HAYES
SHORT TERM...HAYES
LONG TERM...ROBERTSON
AVIATION...HAYES/ROBERTSON
MARINE...HAYES/ROBERTSON
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
810 PM EST SAT JAN 5 2013
.UPDATE (TONIGHT THROUGH SUNDAY NIGHT)...
01Z WATER VAPOR AND H4 RAP ANALYSIS SHOWING AN AMPLIFIED UPPER LEVEL
PATTERN IN PLACE OVER THE CONUS THIS EVENING. LOOKING WEST TO EAST
WE FIND TROUGHING ARRIVING ALONG THE PACIFIC COAST WITH THE FLOW
THEN QUICKLY TURNING BACK NORTH INTO SHARP LONGWAVE RIDGING OVER THE
INTERMOUNTAIN WEST. NORTHERN STREAM FLOW THEN DIPS BACK SOUTH INTO
LONGWAVE TROUGHING WHICH IS CURRENTLY ABSORBING CUT-OFF ENERGY
EJECTING OUT OF THE SOUTHERN PLAINS. THIS TROUGH WILL PASS TO OUR
NORTH THE NEXT 24 HOURS...BUT WILL STILL HAVE ENOUGH SYNOPTIC
INFLUENCE THIS FAR SOUTH TO AID THE LIFT FOR SHOWER AND ISOLATED
STORMS SUNDAY. WV IMAGERY SHOWS ABUNDANT MID/HIGH LEVEL SOUTHERN
STREAM MOISTURE ALREADY STREAMING NORTHWARD AHEAD OF THIS ENERGY
OVER THE GULF OF MEXICO AND SE CONUS.
AT THE SURFACE...FL PENINSULA RESIDES BETWEEN A HIGH PRESSURE RIDGE
ALIGNED ACROSS AL/GA...AND A WEAK QUASI-STATIONARY FRONTAL BOUNDARY
OVER EXTREME SOUTH FLORIDA. A WEAK WAVE OF LOW PRESSURE/IMPULSE
CURRENTLY LOCATED OVER THE WESTERN GULF OF MEXICO LOOKS TO SLOWLY
RIPPLE ALONG THIS BOUNDARY INTO THE EASTERN GULF OF MEXICO AS THE
FRONT RETREATS NORTHWARD OVER THE NEXT 24 HOURS. A BREAK IN ANY
APPRECIABLE LIFTING MECHANISM ALLOWED FOR A DECENT WEATHER DAY
ACROSS THE AREA...ESPECIALLY BY AFTERNOON WHEN MANY AREAS SAW A
DECENT AMOUNT OF SUNSHINE. IN THE PAST FEW HOURS THROUGH...A
RESURGENCE OF LOW LEVEL UPGLIDE AND THE HIGHER LEVEL MOISTURE
ARRIVING FROM THE SOUTHWEST HAVE INCREASED THE CLOUD-COVER ONCE
AGAIN.
REGIONAL RADAR IMAGERY ALREADY SHOWS RAIN COVERAGE EXPANDING TO OUR
WEST OVER THE FL PANHANDLE AND SOUTH INTO THE GULF OF MEXICO. THIS
ACTIVITY IS FORCED BY A COMBINATION OF WEAK LOW LEVEL UPGLIDE...THE
ARRIVAL OF BROAD SYNOPTIC SUPPORT...AND A FAVORABLE POSITIONING
WITHIN THE RIGHT REAR QUADRANT OF A STRONG UPPER JET.
GFS/ECMWF SHOW THIS FAVORABLE LOCATION UNDER THE ENTRANCE TO THE
UPPER JET SLIDING SLOWLY EASTWARD DURING THE NEXT 24 HOURS...AND IT
WILL BE THIS FORCED LIFT ALONG WITH THE LOW LEVEL FOCUS ALONG THE
FRONTAL BOUNDARY THAT WILL INCREASE RAIN CHANCES OVER THE PENINSULA
FOR SUNDAY. BEST CHANCES TO SEE ANY SHOWERS TONIGHT WILL BE OVER THE
FAR NORTHERN COUNTIES...ALTHOUGH UPGLIDE MAY BE JUST ENOUGH TO
SQUEEZE OUT A FEW SPRINKLES FURTHER SOUTH AFTER MIDNIGHT. DURING THE
DAY ON SUNDAY...IT APPEARS THE FURTHER INTO THE DAY WE GET...THE
MORE INGREDIENTS WILL COME TOGETHER FOR THE RAIN. NUMERICAL GUIDANCE
HAS SLOWLY BACKED OFF ON THE TIMING FOR CENTRAL AND SOUTHERN
PORTIONS OF THE AREA DURING THE PAST SEVERAL MODEL RUNS. IF THIS
WERE TO VERIFY THEN THE BEST RAIN CHANCES WILL HOLD OFF FOR THE I-4
CORRIDOR AND SOUTHWARD UNTIL THE AFTERNOON OR EVENING HOURS.
&&
.AVIATION...
STRATO CU LAYERS CONTINUE BUT AS THE EVENING PROGRESSES A GENERAL
LOWERING OF THE BASES IS EXPECTED WITH IFR CONDITIONS OVERNIGHT.
SHRA POSSIBLE PARTICULARLY FOR SOUTHERN AIRPORTS. SOME PATCHY FOG IS
POSSIBLE ALSO.
&&
.MARINE...
A FRONTAL BOUNDARY WILL REMAIN NEARLY STATIONARY ACROSS SOUTHERN
FLORIDA GULF WATERS THROUGH TONIGHT THEN LIFT TO CENTRAL FLORIDA
SUNDAY THROUGH MONDAY. AN AREA OF WEAK LOW PRESSURE WILL TRACKS
ALONG THIS FRONT THROUGH THE EASTERN GULF OF MEXICO SUNDAY AND
SUNDAY NIGHT. HIGH PRESSURE THEN RIDGES IN FROM THE NORTH DURING
THE EARLY PORTION OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 62 76 59 75 / 20 60 70 30
FMY 64 81 64 81 / 10 30 50 20
GIF 59 79 59 75 / 20 60 70 30
SRQ 62 73 61 75 / 20 50 60 30
BKV 56 75 56 75 / 30 70 70 30
SPG 62 75 61 73 / 20 60 70 30
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/MARINE...MROCZKA
AVIATION...PAXTON
AREA FORECAST DISCUSSION...UPDATED
NWS COLUMBIA SC
1020 AM EST FRI JAN 4 2013
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION TONIGHT INTO SATURDAY. A
FRONTAL SYSTEM WILL PROVIDE A CHANCE OF RAIN SATURDAY NIGHT AND
SUNDAY. FAIR WEATHER EXPECTED EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST VISIBLE IMAGERY SHOWING THE EXPANSIVE FOG ACROSS THE
EASTERN MIDLANDS AND PARTS OF THE CSRA. FOG HAS BEGUN TO DISSIPATE
IN THE COLUMBIA AREA AND SHOULD CONTINUE TO DISSIPATE ELSEWHERE
THROUGH 11-11:30AM AS RAP INITIALIZED AND FORECAST SOUNDINGS SHOW
THE MOISTURE IS VERY SHALLOW. TEMPERATURES HAVE BEEN SLOW TO RISE
THIS MORNING DUE TO THE BLANKET OF FOG BUT THEY SHOULD REBOUND
QUICKLY WITH INSOLATION LATE THIS MORNING. FORECAST MAX
TEMPERATURES LOOK REASONABLE GIVEN LATEST THICKNESS ANALYSIS AND
LOCAL TEMPERATURE SCHEME. WILL ADJUST HOURLY GRIDDED FORECAST TO
ACCOUNT FOR LATEST TEMPERATURE AND FOG TRENDS. THERE COULD BE A
BIT MORE HIGH CLOUDS ESPECIALLY ACROSS THE EASTERN MIDLANDS THIS
AFTERNOON WITH SOUTHWESTERLY FLOW ALOFT.
OVERNIGHT...STRONG RADIATIONAL COOLING CONDITIONS ARE EXPECTED
WITH HIGH PRESSURE OVER THE AREA AND TEMPERATURES SHOULD FALL INTO
THE UPPER 20S TO LOWER 30S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
FAIR WEATHER EXPECTED THROUGH SATURDAY...AS SURFACE HIGH PRESSURE
BUILDS INTO THE REGION WITH A DRY ATMOSPHERE IN PLACE. AN UPPER
TROUGH WILL LIFT NE OUT OF THE SOUTHERN PLAINS AND LOWER MISS
VALLEY SATURDAY NIGHT BRINGING INCREASING CLOUDINESS AND THE
POSSIBILITY OF SHOWER ACTIVITY INTO OUR REGION LATE SATURDAY
NIGHT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
NO SIGNIFICANT CHANGES WERE MADE TO THE FORECAST FOR THIS TIME
PERIOD. PREVIOUS DISCUSSION FOLLOWS...
THERE IS CONSIDERABLE UNCERTAINTY NOTED IN THE ENSEMBLE POP
GUIDANCE THROUGH MONDAY WITH THE OPERATIONAL GFS QUITE DRY.
THERE IS UNCERTAINTY LATE IN THE PERIOD AS ANOTHER UPPER LOW MOVES
SLOWLY NORTHEAST.
THE UPPER RIDGE WILL SHIFT EAST INTO THE CENTRAL CONUS SUN/MON.
A WEAK SURFACE FRONT WILL MOVE THROUGH THE REGION SUNDAY.
FORECASTED CHANCE POPS SUNDAY AND WITH CLOUDINESS MOST OF THE DAY
PREFER THE COOLER TEMPERATURE GUIDANCE. CONFIDENCE LIMITED AT THIS
TIME. SURFACE HIGH PRESSURE WILL BUILD INTO THE AREA BEHIND THE
FRONT EARLY TO MID NEXT WEEK. THE MODELS KEEP THE MAIN UPPER FLOW
WELL TO THE NORTH...WITH A CUT-OFF LOW DEVELOPING OVER THE SW
CONUS....AND A SW UPPER FLOW AND HEIGHT RISES OVER OUR REGION.
THIS WILL ALLOW THE AIR MASS TO MODIFY EARLY NEXT WEEK WITH HIGH
TEMPERATURES INCREASING TO ABOVE NORMAL. THERE IS UNCERTAINTY
AGAIN LATE IN THE PERIOD. THE GFS IS MUCH FASTER THAN THE ECMWF
EJECTING AN UPPER-LEVEL LOW NORTHEAST FROM THE DESERT SOUTHWEST.
THE GFS IS MUCH WETTER MIDWEEK. PREFER A SLOWER SOLUTION BECAUSE
AN UPSTREAM KICKER APPEARS TO BE LACKING SO KEPT A DRY FORECAST
UNTIL VERY LATE IN THE PERIOD.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
MORNING FOG IS DISSIPATING AND LIFTING AND VFR CONDITIONS ARE
EXPECTED ALL TERMINALS AFTER 16Z...OGB MAY LINGER MVFR THROUGH
17Z. LIGHT WESTERLY WINDS EXPECTED THIS AFTERNOON UNDER MOSTLY
SUNNY SKIES.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE SATURDAY NIGHT AND
SUNDAY WITH FRONTAL SYSTEM IN THE VICINITY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
929 AM EST FRI JAN 4 2013
.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE REGION THROUGH SATURDAY. A WARM
FRONT WILL LIFT TOWARD THE REGION AND STALL JUST SOUTH AND EAST OF
THE AREA SATURDAY NIGHT. A WAVE OF LOW PRESSURE WILL PASS OFFSHORE
ALONG THE FRONT ON SUNDAY. HIGH PRESSURE WILL THEN BUILD INTO THE
REGION AND PERSIST THROUGH AT LEAST THE BEGINNING OF NEXT WEEK
WITH ANOTHER COLD FRONT POSSIBLE FOR THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SATELLITE AND SURFACE OBSERVATIONS SHOW FOG...LOCALLY
DENSE...LINGERS IN A STRIP FROM ROUGHLY STATESBORO NORTHEAST
THROUGH WALTERBORO AND MONCKS CORNER. THE FOG LAYER LOOKS PRETTY
THIN PER RAP FORECAST SOUNDINGS AND THE 05/12Z CHS RAOB...SO
WOULD EXPECT THE FOG TO BREAKUP PRETTY QUICKLY ONCE THE MORNING
INVERSION MIXES OUT. EXTENDED THE SPECIAL WEATHER STATEMENT
THROUGH 1030 PM TO ADDRESS THE SITUATION.
OTHERWISE...THE REMAINDER OF THE FORECAST IS ON TRACK. OPTED TO
NUDGE SKY COVER INTO THE PARTLY CLOUDY CATEGORY AS CIRRUS
ASSOCIATED WITH THE SUBTROPICAL JET IS POISED TO MOVE IN FROM THE
SOUTHWEST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
TONIGHT...A SHORT WAVE TROUGH WILL SKIRT BY TO THE NORTH AS
SURFACE HIGH PRESSURE BUILDS INTO THE REGION FROM THE TENNESSEE
VALLEY. A VERY DRY AIRMASS...CLEAR SKIES AND LIGHT WINDS WILL
PROMOTE GOOD RADIATIONAL COOLING WITH LOWS IN THE LOWER 30S IN
WELL SHELTERED/LOW-LYING INLAND LOCATIONS AND THE MID 30S
ELSEWHERE AWAY FROM WARMER COASTAL AREAS.
HIGH PRESSURE TO START SATURDAY WILL WEAKEN THROUGH THE DAY BUT
SHOULD KEEP THINGS DRY AS THE DEEPER MOISTURE REMAINS SOUTH AND WEST
OF THE AREA. HOWEVER...RAIN CHANCES WILL INCREASE SLIGHTLY SATURDAY
NIGHT INTO SUNDAY...MAINLY ACROSS SOUTHEAST GEORGIA...AS MOISTURE
INCREASES AND AN UPPER JET STRENGTHENS NORTH OF THE AREA OVER THE
MID ATLANTIC REGION. HIGH PRESSURE WILL THEN BUILD FROM THE
NORTHWEST LATER SUNDAY THROUGH MONDAY WITH DRY WEATHER PREVAILING.
TEMPERATURES LOOK TO BE RELATIVELY CLOSE TO NORMAL FOR THIS TIME OF
YEAR...AROUND 60 FOR HIGHS AND AROUND 40 FOR LOWS /EXCEPT SUNDAY
MORNING WHEN LOWER TO MID 40S ARE EXPECTED DUE TO THE CLOUDS/RAIN/.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
THE FORECAST BECOMES MUCH MORE UNCERTAIN THIS PERIOD...MAINLY DUE TO
THE TIMING OF A COLD FRONT FOR MID WEEK. DECIDED TO FOLLOW THE
SLOWER ECMWF/CMC/HPC GUIDANCE WHICH INDICATES MOSTLY DRY CONDITIONS
INTO WEDNESDAY WITH HIGH PRESSURE PREVAILING. WILL CARRY SOME LOW
RAIN CHANCES THROUGH THURSDAY NIGHT. THE MAIN CONCERN THIS PERIOD
WILL BE THE POTENTIAL FOR SOME STRONG TO POSSIBLY SEVERE STORMS
WEDNESDAY AS THE FASTER GFS SOLUTION INDICATES. TEMPERATURES SHOULD
BE NEAR TO ABOVE NORMAL.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
KCHS...FOG IS EXPECTED TO REDUCE VISIBILITIES TO MVFR LEVELS
THROUGH ABOUT 14Z...WITH TEMPORARY REDUCTIONS IN VISIBILITIES
AND/OR CEILINGS TO IFR OR LOWER LEVELS POSSIBLE. VFR CONDITIONS
ARE THEN EXPECTED TO PREVAIL THROUGH 12Z SATURDAY.
KSAV...LOW STRATUS WITH MVFR CEILINGS WILL PERSIST THROUGH ABOUT
15Z. IF THE CLOUDS CLEAR ANY SOONER...THEN PATCHY FOG COULD RESULT
IN SOME REDUCED VISIBILITIES AT THE TERMINAL. VFR CONDITIONS ARE
THEN EXPECTED TO PREVAIL THROUGH 12Z SATURDAY.
EXTENDED AVIATION OUTLOOK...VFR CONDITIONS WILL PREVAIL THROUGH
SATURDAY. MVFR OR LOWER CONDITIONS MAY DEVELOP SATURDAY NIGHT INTO
SUNDAY DUE TO LOW CEILINGS AND RAIN.
&&
.MARINE...
TODAY AND TONIGHT...A NORTHERLY FLOW WILL PREVAIL OVER THE WATERS
AS HIGH PRESSURE BUILDS INTO THE REGION FROM THE WEST. A TIGHT
SURFACE PRESSURE GRADIENT AND WEAK COLD AIR ADVECTION THIS MORNING
COULD CAUSE WINDS TO SURGE UPWARDS OF 15-20 KT AT TIMES...BUT ONCE
THE GRADIENT WEAKENS LATE THIS MORNING WINDS SHOULD REMAIN AROUND
15 KT OR LESS ACROSS ALL WATERS THROUGH TONIGHT. SEAS WILL BE AS
HIGH AS 3-4 FT IN THE OUTER GEORGIA WATERS AND 2-3 FT IN THE NEAR
SHORE WATERS THIS MORNING...BEFORE SUBSIDING TO 3 FT OR LESS
THROUGHOUT THIS AFTERNOON AND TONIGHT AS WINDS DIMINISH.
SATURDAY THROUGH WEDNESDAY...HIGH PRESSURE WILL SLIDE NORTH OF THE
AREA SATURDAY WITH A WAVE OF LOW PRESSURE DEVELOPING OVER OR NEAR
THE AREA INTO SUNDAY. HIGH PRESSURE WILL THEN RETURN INTO EARLY NEXT
WEEK AS THE LOW PULLS AWAY WITH A COASTAL TROUGH OF LOW PRESSURE
POSSIBLY DEVELOPING. CONDITIONS LOOK TO GO DOWNHILL INTO MONDAY DUE
TO THE ELEVATED NORTH/NORTHEAST FLOW AND SMALL CRAFT ADVISORIES ARE
A GOOD BET AT LEAST BEYOND 20 NM. BEYOND THIS TIME THE FORECAST GETS
A LOT MORE UNCERTAIN DUE TO THE TIMING OF THE NEXT COLD FRONT WHICH
COULD ARRIVE AS EARLY AS WEDNESDAY NIGHT. IF THIS
OCCURS...WINDS/SEAS WILL BE MUCH HIGHER THAN CURRENTLY FORECAST DUE
TO A STRONG SOUTHERLY SURGE AHEAD OF THE FRONT...ESPECIALLY ACROSS
THE WARMER WATERS BEYOND 20 NM FROM SHORE WHERE MIXING WILL BE
GREATER.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
432 AM EST FRI JAN 4 2013
.SYNOPSIS...
A WEAK SURFACE TROUGH WILL MOVE THROUGH TODAY. HIGH PRESSURE WILL
BUILD INTO THE REGION TONIGHT INTO SATURDAY. A FRONTAL SYSTEM
WILL PROVIDE A CHANCE OF RAIN SATURDAY NIGHT AND SUNDAY. FAIR
WEATHER EXPECTED EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...
RECENT OBSERVATIONS SUGGEST SOME VARIABILITY IN VISIBILITIES.
DENSE FOG MAY NOT BE WIDESPREAD ENOUGH TO WARRANT A DENSE FOG
ADVISORY...BUT COMBINATION OF PATCHY DENSE FOG AND TEMPERATURES
NEAR FREEZING WARRANTS A SPECIAL WEATHER STATEMENT FOR REDUCED
VISIBILITIES AND POSSIBILITY OF BLACK ICE ON BRIDGES.
PREVIOUS DISCUSSION...
MAIN NEAR TERM CONCERN IS POTENTIAL FOR DENSE FOG OVER MUCH OF THE
FORECAST AREA. WEAK INVERTED SURFACE TROUGH AND
ASSOCIATED CLOUDINESS SHIFTING SOUTH OF THE FA. DESPITE SOME WEAK
COOL AND DRY ADVECTION...LOW DEWPOINT DEPRESSIONS AND LIGHT WINDS
WHERE SKIES HAVE CLEARED HAS RESULTED IN FOG DEVELOPMENT OVER
THE NORTHERN FA...WITH VISIBILITIES ONE HALF MILE OF LESS IN SOME
LOCATIONS. LATEST NEAR TERM HIGH RESOLUTION MODELS SUGGEST DENSE
FOG COULD SPREAD SW INTO THE CENTRAL FA AND POSSIBLY PORTIONS OF
THE CSRA LATER TONIGHT. WILL HAVE TO MONITOR FOR THE POSSIBILITY OF
ISSUING A DENSE FOG ADVISORY. IMPORTANT NOTE...TEMPERATURES WILL
BE NEAR OR BELOW FREEZING IN SOME LOCATIONS ACROSS THE NORTHERN
AND CENTRAL FA WHERE DENSE FOG MAY FORM. THIS COULD LEAD TO SOME
BLACK ICE OR SLICK SPOTS ON BRIDGES AND OVERPASSES. IF THIS
APPEARS TO DEVELOP...WILL HANDLE WITH SPECIAL WEATHER STATEMENT.
OTHERWISE...FAIR AND DRY WEATHER EXPECTED TODAY...WITH SUNNY SKIES
EXPECTED AFTER MORNING FOG DISSIPATED. HIGH PRESSURE WILL REMAIN
CENTERED TO OUR WEST TODAY...AS A WEAK SURFACE TROUGH AHEAD OF AN
UPPER DISTURBANCE...MOVES THROUGH THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
FAIR WEATHER EXPECTED THROUGH SATURDAY...AS SURFACE HIGH PRESSURE
BUILDS INTO THE REGION WITH A DRY ATMOSPHERE IN PLACE. AN UPPER
TROUGH WILL LIFT NE OUT OF THE SOUTHERN PLAINS AND LOWER MISS
VALLEY SATURDAY NIGHT BRINGING INCREASING CLOUDINESS AND THE
POSSIBILITY OF SHOWER ACTIVITY INTO OUR REGION LATE SATURDAY
NIGHT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
NO SIGNIFICANT CHANGES WERE MADE TO THE FORECAST FOR THIS TIME
PERIOD. PREVIOUS DISCUSSION FOLLOWS...
THERE IS CONSIDERABLE UNCERTAINTY NOTED IN THE ENSEMBLE POP
GUIDANCE THROUGH MONDAY WITH THE OPERATIONAL GFS QUITE DRY.
THERE IS UNCERTAINTY LATE IN THE PERIOD AS ANOTHER UPPER LOW MOVES
SLOWLY NORTHEAST.
THE UPPER RIDGE WILL SHIFT EAST INTO THE CENTRAL CONUS SUN/MON.
A WEAK SURFACE FRONT WILL MOVE THROUGH THE REGION SUNDAY.
FORECASTED CHANCE POPS SUNDAY AND WITH CLOUDINESS MOST OF THE DAY
PREFER THE COOLER TEMPERATURE GUIDANCE. CONFIDENCE LIMITED AT THIS
TIME. SURFACE HIGH PRESSURE WILL BUILD INTO THE AREA BEHIND THE
FRONT EARLY TO MID NEXT WEEK. THE MODELS KEEP THE MAIN UPPER FLOW
WELL TO THE NORTH...WITH A CUT-OFF LOW DEVELOPING OVER THE SW
CONUS....AND A SW UPPER FLOW AND HEIGHT RISES OVER OUR REGION.
THIS WILL ALLOW THE AIR MASS TO MODIFY EARLY NEXT WEEK WITH HIGH
TEMPERATURES INCREASING TO ABOVE NORMAL. THERE IS UNCERTAINTY
AGAIN LATE IN THE PERIOD. THE GFS IS MUCH FASTER THAN THE ECMWF
EJECTING AN UPPER-LEVEL LOW NORTHEAST FROM THE DESERT SOUTHWEST.
THE GFS IS MUCH WETTER MIDWEEK. PREFER A SLOWER SOLUTION BECAUSE
AN UPSTREAM KICKER APPEARS TO BE LACKING SO KEPT A DRY FORECAST
UNTIL VERY LATE IN THE PERIOD.
&&
.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
BOTH MODELS AND SATELLITE IMAGERY SHOWS DRIER AIR MOVING IN MAINLY
FROM 2 KFT AND ABOVE. RUC FORECAST SOUNDINGS KEEP SOME LEVEL MOISTURE
CLOSE TO THE SURFACE. SATELLITE SHOWS CLEARING MOVING SOUTH. THIS
IS EXPECTED TO ALLOW FOR RADIATIONAL COOLING AND THE POSSIBILITY
OF RADIATIONAL FOG DEVELOPING. TEMPERATURES HAVE DROPPED TO NEAR
DEWPOINT READINGS ACROSS THE REGION. THIS SHOULD ALLOW FOR
WIDESPREAD FOG. IFR CONDITIONS PREVAIL AT CAE/CUB/OGB. STILL NOT
IFR AT AGS/DNL BUT WITH ADDITIONAL RADIATIVE COOLING...EXPECT IFR
CONDITIONS THESE TAF SITES ALSO BY 10-11Z. VSBYS HAVE REMAINED 1/2
MILE OR GREATER ACROSS AREA. ALTHOUGH OGB DROPPED TO 1/4 MILE. SO
NO WIDESPREAD DENSE FOG FOR TIME BEING BUT WILL CONTINUE TO
MONITOR. AFTER SUNRISE...WITH SOLAR HEATING...EXPECT FOG TO BREAK
UP BY 14Z WITH VFR CONDITIONS BY 15Z.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE SATURDAY NIGHT AND
SUNDAY WITH FRONTAL SYSTEM IN THE VICINITY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
321 AM EST FRI JAN 4 2013
.SHORT TERM /TODAY THROUGH SATURDAY NIGHT/...
MODELS IN PRETTY GOOD AGREEMENT THROUGH 48 HOURS. A NARROW BAND OF
LOW CLOUDS WILL MOVE INTO CENTRAL GA BY 12Z AND THEN DISSIPATE AFTER
SUNRISE. THIS SHOULD MAKE FOR A MOSTLY SUNNY DAY AND MOSTLY CLEAR
NIGHT TONIGHT. THE NEXT SYSTEM IS CURRENTLY ORGANIZING OVER THE
SOUTHERN ROCKIES AND WILL MOVE RAPIDLY NORTHEAST AND WEAKEN OVER THE
NEXT 48 HOURS. THIS WILL BRING A WEAK SHORT WAVE OVER THE CWA LATE
SATURDAY INTO SATURDAY NIGHT. THE SYSTEM WILL BE LACKING
MOISTURE...HOWEVER THERE SHOULD BE ENOUGH MOISTURE FOR SCATTERED
SHOWERS...MOVING INTO THE WESTERN HALF OF THE CWA SATURDAY AFTERNOON
AND ACROSS THE ENTIRE CWA SATURDAY NIGHT. TEMPERATURES SATURDAY
NIGHT SHOULD BE WARM ENOUGH FOR THE PRECIP TO FALL AS RAIN...DO NOT
EXPECT ANY FROZEN PRECIP SATURDAY NIGHT.
GUIDANCE HAS NOT BEEN DOING TOO WELL WITH TEMPS. LOCAL BIAS TABLES
INDICATE GUIDANCE HAS BEEN RUNNING 2 TO 4 DEGREES TOO WARM FOR
DAYTIME HIGHS AND 2 TO 4 DEGREES TOO COLD FOR NIGHTTIME LOWS OVER
THE PAST 5 TO 10 DAYS WITH THE NAM HAVING THE LARGEST BIAS ERRORS.
HAVE THEREFORE MADE ADJUSTMENTS FOR THIS IN MAX AND MIN TEMPS TODAY
THROUGH SATURDAY NIGHT.
17
.LONG TERM /SUNDAY THROUGH THURSDAY/...
THE LAST IN A SERIES OF QUICK MOVING SHORT WAVES SWEEPS BY TO THE
NORTH OF GEORGIA SUNDAY...BUT MODELS ARE NOT GENERATING ANY
SIGNIFICANT PRECIPITATION ASSOCIATED WITH THIS. I HAVE KEPT SOME
LINGERING POPS IN THE SOUTHEAST SUNDAY...BUT THIS IS GENERALLY FOR
EARLY IN THE DAY WITH THE EXITING INITIAL SYSTEM. GFS AND ECMWF
CONTINUE TO HAVE NOTICEABLE DIFFERENCES IN THE LONGER TERM TRENDS
WITH THE GFS CONTINUING TO BE MORE OPEN AND PROGRESSIVE WITH THE
UPPER LEVEL PATTERN. BOTH SHOW RIDGING ACROSS THE REGION AT THE
BEGINNING OF THE WEEK...HOWEVER THEY DIFFER SIGNIFICANTLY ON THE
RESOLUTION OF THE NEXT UPPER TROUGH/LOW. GFS KEEPS THIS WAVE OPEN AND
MOVES IT ACROSS THE CENTRAL/SOUTHERN ROCKIES AND OUT ONTO THE PLAINS
BY MIDWEEK WHILE THE ECMWF CLOSES OF THE LOW AND DIGS IT INTO THE BIG
BEND REGION. GFS SWEEPS A FAIRLY SHARP AND DEEP TROUGH ACROSS THE
FORECAST AREA WEDNESDAY WITH AN ASSOCIATED STRONG FRONTAL BOUNDARY
SWEEPING ACROSS GEORGIA. EURO- MODEL LIFTS THE LOW SHARPLY NORTHEAST
INTO THE GREAT LAKES BY THE LATTER HALF OF THE WEEK. THE GFS IS
GENERATING PRECIPITATION ACROSS THE AREA BEGINNING AS EARLY AS
TUESDAY NIGHT WITH HIGHEST QPF NUMBERS WEDNESDAY...AND THEN ENDS
PRECIPITATION BY THURSDAY MORNING. ECMWF KEEPS THE STATE DRY THROUGH
MUCH OF WEDNESDAY NIGHT AND ONLY SPREADS MINIMAL QPF NUMBERS ACROSS
THE FORECAST AREA THURSDAY. I AM BASING MY EXTENDED FORECAST
GENERALLY ON THE GFS SOLUTION. THE 00Z NAM ENDS ITS RUN AT 12Z MONDAY
IN FAIRLY GOOD AGREEMENT WITH THE MORE OPEN/PROGRESSIVE GFS. THIS
WOULD BRING THE BETTER CHANCES FOR PRECIPITATION TO THE AREA
WEDNESDAY/WEDNESDAY NIGHT WHICH IS A BIT FASTER THAN THE PREVIOUS
EXTENDED FORECAST GRIDS. RIGHT NOW INSTABILITY IS MARGINAL AT BEST
FOR THUNDER AND WITH SUCH UNCERTAINTY CONTINUING IN THE ULTIMATE
SOLUTION FOR THIS WHOLE SYSTEM I WILL REFRAIN FROM MENTIONING THUNDER
FOR NOW.
20
&&
AVIATION...
06Z UPDATE...
A BAND OF MVFR CLOUDS WAS MOVING SOUTHWEST OUT OF SC AND INTO
EASTERN GA. RUC AND MAV HAVE THIS AREA MOVING INTO CENTRAL GA BY
12Z. THIS AREA JUST BRUSHES THE ATL AREA AND WILL NEED TO ADD SCT015
AFTER 10Z. THIS AREA SHOULD MOVE INTO MCN AND WILL ADD A SCT TEMPO
BKN015. THESE LOW CLOUDS SHOULD DISSIPATE AFTER 14Z AND THEN
CONDITIONS SHOULD BE VFR FOR THE REST OF THE FORECAST. WINDS WILL BE
NEAR CALM EARLY THIS MORNING...NORTHWEST LESS THAN 10 KTS DURING THE
DAY AND THEN DIMINISHING AFTER SUNSET TO NEAR CALM.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM ON MVFR CLOUDS EARLY THIS MORNING.
HIGH ON ALL REMAINING ELEMENTS.
17
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 53 31 53 39 / 0 0 10 20
ATLANTA 51 32 51 40 / 0 0 30 30
BLAIRSVILLE 47 27 49 34 / 0 0 20 20
CARTERSVILLE 49 27 49 35 / 0 0 30 20
COLUMBUS 56 34 57 43 / 0 0 30 30
GAINESVILLE 50 31 51 38 / 5 0 20 20
MACON 55 31 58 40 / 0 0 10 30
ROME 50 28 51 34 / 0 0 30 20
PEACHTREE CITY 51 30 51 37 / 0 0 30 30
VIDALIA 55 38 59 48 / 0 0 5 30
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...17
LONG TERM....20
AVIATION...17
AREA FORECAST DISCUSSION...UPDATE
NWS PEACHTREE CITY GA
1228 AM EST FRI JAN 4 2013
.EVENING UPDATE...
/ISSUED AT 1022 PM EST THU JAN 3 2013/
SKIES HAVE CLEARED AS EXPECTED WITH A NW WIND FLOW SPREADING A DRY
AND COLD AIR MASS OVER THE FORECAST AREA. DEWPOINTS IN THE 20S AND
30S STILL SUPPORT PROJECTED OVERNIGHT LOWS OF THE SAME. MAY SEE SOME
PATCHY FOG BRIEFLY DOWN AROUND EASTMAN... SWAINSBORO AND VIDALIA
WHERE THE WARMER DEWPOINTS IN THE UPPER 30S ARE NOTED... BUT THIS
SHOULD BE SHORT LIVED AS DRIER AIR CONTINUES TO SPREAD SOUTHWARD
OVERNIGHT. OTHERWISE... NO MAJOR CHANGES TO THE FORECAST SEEM
NECESSARY AT THIS TIME. /39
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
/ISSUED AT 230 PM EST THU JAN 3 2013/
A WEAK WAVE CURRENTLY MOVING ACROSS SOUTH GEORGIA HAS BROUGHT
INCREASED CLOUD COVER TO THE REGION WITH SHOWERS ACROSS SOUTH AND
CENTRAL GA. HIGH PRESSURE IS BEGINNING TO BUILD EAST OUT OF THE
CENTRAL PLAINS AND WILL CONTINUE SO THROUGH FRIDAY. THIS RIDGE WILL
BECOME CENTERED OVER GA BY 00-06Z SAT. THIS RIDGE WILL KEEP NORTH
AND CENTRAL GA PRECIPITATION FREE TONIGHT THROUGH SAT MORNING. THERE
IS ANOTHER WAVE THAT MOVES NORTH OUT OF THE GULF SAT. THIS SECOND
WAVE SHOULD BRING MORE PRECIP TO THE AREA BUT THE MODELS SHOW IT
DRYING AS IT MOVES ACROSS THE STATE. THIS WAVE MOVES RIGHT INTO THE
BACKSIDE OF THE HIGH PRESSURE RIDGE THAT WILL ALREADY BE IN PLACE.
JUST HOW MUCH RAIN WILL DEPEND OF HOW STRONG THE RIDGE IS OR HOW
STRONG THE WAVE IS. WILL HAVE TO MONITOR THIS SITUATION OVER THE
NEXT FEW DAYS.
01
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
/ISSUED AT 230 PM EST THU JAN 3 2013/
GFS/NAM SIGNIFICANTLY DIFFERING WITH RAIN CHANCES SATURDAY NIGHT.
HAVE TWEAKED THE FORECAST TO REFLECT A COMPROMISE BETWEEN A WETTER
NAM AND A DRIER GFS. EITHER WAY RAIN AMOUNTS SHOULD BE LIGHT.
TOO MUCH UNCERTAINTY BEYOND TO MAKE MAJOR CHANGES AT THIS
TIME...ESPECIALLY IN THE WEDNESDAY TO THURSDAY TIME FRAME WITH THE
12Z GFS MUCH FASTER THAN THE 12Z EUROPEAN WITH THE NEXT WEATHER
SYSTEM.
BDL
PREVIOUS DISCUSSION...
BOTH THE GFS AND ECMWF CONTINUE WITH THE SHORTWAVES MOVING ACROSS
THE GULF...WHILE THE NEXT POTENTIAL WEATHER MAKER MOVES INTO THE
MID-MISSISSIPPI VALLEY. THE GFS HAS A MUCH DEEPER LAYER OF
MOISTURE ASSOCIATED WITH THIS SYSTEM. AS IT LIFTS INTO THE OHIO
VALLEY...IT POSES A THREAT OF LIGHT RAIN FOR NORTHWEST GEORGIA
SATURDAY AFTERNOON..WHILE A LOW MOVING FROM THE WESTERN GULF
SPREADS MOISTURE INTO SOUTHEAST GEORGIA THAT COULD RENDER SOME
BRIEF LIGHT RAIN TO THE AREA SATURDAY NIGHT INTO SUNDAY MORNING.
THE PASSING OF THESE SYSTEMS WILL LEAVE THE AREA WITH DRY
CONDITIONS ONCE AGAIN...WHICH CURRENTLY GOES THROUGH WEDNESDAY.
37
&&
.AVIATION...
06Z UPDATE...
A BAND OF MVFR CLOUDS WAS MOVING SOUTHWEST OUT OF SC AND INTO
EASTERN GA. RUC AND MAV HAVE THIS AREA MOVING INTO CENTRAL GA BY
12Z. THIS AREA JUST BRUSHES THE ATL AREA AND WILL NEED TO ADD SCT015
AFTER 10Z. THIS AREA SHOULD MOVE INTO MCN AND WILL ADD A SCT TEMPO
BKN015. THESE LOW CLOUDS SHOULD DISSIPATE AFTER 14Z AND THEN
CONDITIONS SHOULD BE VFR FOR THE REST OF THE FORECAST. WINDS WILL BE
NEAR CALM EARLY THIS MORNING...NORTHWEST LESS THAN 10 KTS DURING THE
DAY AND THEN DIMINISHING AFTER SUNSET TO NEAR CALM.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM ON MVFR CLOUDS EARLY THIS MORNING.
HIGH ON ALL REMAINING ELEMENTS.
17
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 30 52 31 53 / 0 0 0 10
ATLANTA 31 51 33 51 / 0 0 0 10
BLAIRSVILLE 26 50 26 51 / 0 0 0 20
CARTERSVILLE 27 50 28 51 / 0 0 0 20
COLUMBUS 33 55 33 56 / 0 0 0 20
GAINESVILLE 31 51 32 52 / 0 5 0 20
MACON 32 55 31 56 / 0 0 0 10
ROME 25 51 26 51 / 0 0 5 30
PEACHTREE CITY 27 51 28 51 / 0 0 0 10
VIDALIA 36 60 38 60 / 5 0 0 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...01/39
LONG TERM....BDL
AVIATION...39
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
359 PM EST SAT JAN 5 2013
.SHORT TERM...THROUGH SUNDAY NIGHT.
BAND OF LIGHT SNOW THAT BEGAN ACROSS PORTIONS OF ILLINOIS HAS BEEN
MOVING STEADILY NORTHEAST...JUST ARRIVING IN OUR FAR SW COUNTIES.
VSBYS OF 1 TO 3 SM HAVE BEEN COMMON FOR AN HOUR OR 2 IN ECNTRL
ILLINOIS DURING PASSAGE OF THIS BAND WITH SIMILAR CONDITIONS
EXPECTED ACROSS THE AREA THROUGH EARLY EVENING. SOME CONCERNS HOW
FAR NE THE BAND WILL MAKE IT...BUT WITH ENERGY STILL MODERATELY
STRONG AND CONTINUING ITS NE TRACK PER WATER VAPOR LOOP SEE NO
REASON WHY IT WON`T CONTINUE. HAVE EXPANDED POPS AND TRIED TO ADD
SOME DETAIL TO GRIDS WITH BULK OF PRECIP OCCURRING PRIOR TO 00Z.
AFTER DEPARTURE OF THE BAND WILL MAINTAIN CHC POPS ALL AREAS EXCEPT
NW WHERE LIKELY POPS WILL REMAIN AS UPSTREAM TRENDS ACROSS MISSOURI
INDICATE ANOTHER AREA OF PRECIP ATTEMPTING TO TAKE SHAPE. THIS WILL
LIKELY AFFECT MAINLY NW AREAS BUT DON`T WANT TO GET TOO CUTE WITH
POPS TO WENT WITH SLOW DOWNWARD TREND ACROSS THE AREA THROUGH THE
EVENING. TEMPS SHOULD REMAIN AROUND FREEZING...KEEPING ROAD
CONDITIONS MANAGEABLE.
LATER TONIGHT MOISTURE WILL BE MORE SHALLOW IN NATURE AS NORTHERN
STREAM ENERGY ARRIVES AND COLD FRONT APPROACHES DEEPER. WEAK LIFT
WILL CONTINUE IN ADVANCE OF THESE FEATURES WITH BULK OF MODELS
SOUNDINGS STILL SHOWING A LACK OF ICE CRYSTAL FORMATION...ALTHOUGH
TEMPS NEAR THE -9 TO -10 C RANGE SUGGESTS COULD BE A CLOSE CALL.
THESE CONDITIONS MAY PERSIST UNTIL FROPA OCCURS DURING THE DAY
SUNDAY. HAVE OPTED TO EXPAND MENTION OF EITHER SNOWSHOWERS OR
FREEZING DRIZZLE THROUGH MUCH OF SUNDAY WITH FUTURE FORECAST
HOPEFULLY PROVIDING BETTER DETAIL ON DEPARTURE. AS HAS BEEN
DISCUSSED...OVERNIGHT TEMPS WILL HOVER AROUND OR JUST BELOW
FREEZING...POSSIBLY CAUSING SOME SLICK SPOTS ON UNTREATED SURFACES.
WILL DEFER ANY SPS OR HEADLINES TO EVE/OVERNIGHT SHIFTS TO MONITOR
DEVELOPMENT.
DRIER AIR WILL QUICKLY MOVE IN BY SUNDAY NIGHT WITH CLEARING SKIES
AND TEMPS DROPPING BACK INTO THE UPR TEENS TO LOWER 20S.
&&
.LONG TERM...MONDAY THROUGH SATURDAY
LOW LEVEL RIDGE AXIS WILL SHIFT EAST OF THE AREA ON MONDAY WITH
SOUTHWEST LOW LEVEL WINDS INCREASING THROUGH THE DAY. FAIRLY STRONG
LOW LEVEL WAA TO ACCOMPANY THESE SOUTHWEST WINDS...ALTHOUGH COMBINED
EFFECTS OF WAA AND SNOW COVER STILL LENDS SOME QUESTION AS TO HOW
MUCH WARMING WILL BE REALIZED AT THE SURFACE. HAVE STARTED TO MAKE
SOME DENT IN DIMINISHING SNOW COVER THIS WEEKEND...BUT MANY AREAS
THIS MORNING STILL REPORTING 2 TO 4 INCH SNOWCOVER ACROSS
EAST/SOUTHEAST PORTIONS OF THE AREA. WARMEST TEMPS ON MONDAY
EXPECTED IN THE NORTHWEST WHERE SOME MID TO EVEN A FEW UPPER 30S
WILL BE POSSIBLE.
CUT OFF UPPER LOW WILL CONTINUE TO DIG ACROSS NORTHERN MEXICO ON
TUESDAY. THE EVOLUTION OF THIS FEATURE WILL BE THE MAIN PLAYER IN
LOCAL AREA WEATHER THROUGH THE UPCOMING WEEK. TRENDS OVER THE PAST
SEVERAL RUNS HAVE BEEN TOWARD CONVERGENCE TO THE SLOWER GEM/ECMWF
IDEA OF A MORE PRONOUNCED CUT-OFF. DPROG/DT ALSO INDICATING SOME
SIGNIFICANT SLOWING IN THE SLOWER GEM/ECMWF CLUSTER LARGELY AS A
RESULT OF A SLOWER SOLUTION WITH LARGER SCALE EASTERN PACIFIC TROUGH
REACHING WESTERN CONUS DURING THIS PERIOD. RESIDENCE TIME OF DRY LOW
LEVEL AIR NOW LOOKS TO BE A BIT LONGER ACROSS THE LOCAL AREA
WEDNESDAY NIGHT INTO EARLY THURSDAY AND HAVE LOWERED POPS WEDNESDAY
NIGHT TO ACCOUNT FOR THIS SLOWER TREND. WHILE CONFIDENCE IN PRECIP
OVER A 24 TO 36 HOUR PERIOD IS INCREASING FOR THE THURSDAY/FRIDAY
MORNING PERIOD...LINGERING LARGE SPREAD AND RECENT SLOWING TREND DO
NOT QUITE OFFER ENOUGH CONFIDENCE IN GOING WITH LIKELY POPS FOR ANY
ONE PERIOD...ALTHOUGH BEST CHANCES OF RAIN AT THIS TIME APPEAR TO BE
IN THE LATE THURSDAY/THURSDAY NIGHT PERIOD. IN TRENDING TO THE
SLOWER SOLUTION...HAVE ALSO ADDED SOME LOW CHANCE -RA POPS ON
FRIDAY. THERE MAY BE A NARROW WINDOW OF SOME ISOLD THUNDER POTENTIAL
DURING THIS PERIOD AS LOW LEVEL THERMAL THETAE SURGES NORTHWARD AND
UPPER LEVEL DYNAMICS INCREASE...BUT WILL OMIT ANY MENTION FOR NOW.
HIGHER THAN NORMAL CONFIDENCE PERSISTS FOR ABOVE NORMAL TEMPERATURES
FOR MIDDLE AND LATTER PORTIONS OF NEXT WEEK. MEDIUM RANGE MODELS ARE
IN REASONABLE AGREEMENT IN AMPLIFIED WESTERN TROUGH/EASTERN RIDGE
PATTERN SETTING UP TOWARD THE END OF THE PERIOD WITH NEXT PRECIP
CHANCES LIKELY HOLDING OFF UNTIL AFTER THIS FORECAST VALID PERIOD.
&&
.AVIATION...
NO SIG CHANGES TO PREV TAF WITH QUESTIONS LINGERING ON
DEVELOPMENT/TIMING/LOCATION OF LIGHT SNOW LATE AFTN/EARLY EVE AND
RISK FOR FREEZING DRIZZLE OVERNIGHT. VIS SAT SHOWS AREA OF CLOUDS
OVER IL APPEARING MORE CONVECTIVE IN NATURE JUST AHEAD OF THE WAVE
EJECTING NE AND SLOWLY WEAKENING. LIGHT RADAR RETURNS HAVE
PERSISTED FOR SEVERAL HOURS WITH THIS FEATURE BUT LITTLE IN THE
WAY OF GROUND CONFIRMATION HAS BEEN OBSERVED WITH CLOUD BASES
QUITE HIGH. BULK OF MODEL DATA HAS BEEN SUGGESTING THAT PRECIP
WILL REMAIN MAINLY NORTH OF KFWA AND JUST GRAZE KSBN TOWARDS 00Z.
14Z HRRR NOW TRYING TO DEVELOP/EXPAND CURRENT AREA OVER IL AND
MOVE THIS IN OVER THE NEXT COUPLE OF HOURS. GIVEN ABOVE
SUPPORT...WILL MAINTAIN DRY VFR CONDITIONS UNTIL CLOSER TO 00Z
WHEN INTERACTION WITH WAVE MOVING ACROSS THE EASTERN PLAINS
BEGINS. CONCERNED THAT ARRIVAL OF LOWER CLOUDS COULD BE LATER THAN
DEPICTED WITH LITTLE/NO LOW CLOUD COVER NOTED WITH ENERGY IN IL/MO
BUT MVFR/IFR CIGS ACROSS THE DAKOTAS. STATUS QUOT IS BEST WAY TO GO
FOR NOW WITH CONTINUED MONITORING AND POSSIBLE AMENDMENTS TO TAFS
THROUGH THE AFTERNOON. FREEZING DRIZZLE THREAT STILL EXISTS LATE
TONIGHT AND POSSIBLY INTO SUNDAY WITH BETTER MSTR FROM NORTHERN
WAVE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 6 PM EST SUNDAY
FOR LMZ043-046.
&&
$$
SHORT TERM...FISHER
LONG TERM...MARSILI
AVIATION...FISHER
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
111 PM EST SAT JAN 5 2013
.AVIATION...
NO SIG CHANGES TO PREV TAF WITH QUESTIONS LINGERING ON
DEVELOPMENT/TIMING/LOCATION OF LIGHT SNOW LATE AFTN/EARLY EVE AND
RISK FOR FREEZING DRIZZLE OVERNIGHT. VIS SAT SHOWS AREA OF CLOUDS
OVER IL APPEARING MORE CONVECTIVE IN NATURE JUST AHEAD OF THE WAVE
EJECTING NE AND SLOWLY WEAKENING. LIGHT RADAR RETURNS HAVE
PERSISTED FOR SEVERAL HOURS WITH THIS FEATURE BUT LITTLE IN THE
WAY OF GROUND CONFIRMATION HAS BEEN OBSERVED WITH CLOUD BASES
QUITE HIGH. BULK OF MODEL DATA HAS BEEN SUGGESTING THAT PRECIP
WILL REMAIN MAINLY NORTH OF KFWA AND JUST GRAZE KSBN TOWARDS 00Z.
14Z HRRR NOW TRYING TO DEVELOP/EXPAND CURRENT AREA OVER IL AND
MOVE THIS IN OVER THE NEXT COUPLE OF HOURS. GIVEN ABOVE
SUPPORT...WILL MAINTAIN DRY VFR CONDITIONS UNTIL CLOSER TO 00Z
WHEN INTERACTION WITH WAVE MOVING ACROSS THE EASTERN PLAINS
BEGINS. CONCERNED THAT ARRIVAL OF LOWER CLOUDS COULD BE LATER THAN
DEPICTED WITH LITTLE/NO LOW CLOUD COVER NOTED WITH ENERGY IN IL/MO
BUT MVFR/IFR CIGS ACROSS THE DAKOTAS. STATUS QUOT IS BEST WAY TO GO
FOR NOW WITH CONTINUED MONITORING AND POSSIBLE AMENDMENTS TO TAFS
THROUGH THE AFTERNOON. FREEZING DRIZZLE THREAT STILL EXISTS LATE
TONIGHT AND POSSIBLY INTO SUNDAY WITH BETTER MSTR FROM NORTHERN
WAVE.
&&
.PREV DISCUSSION... /ISSUED 356 AM EST SAT JAN 5 2013/
SHORT TERM.../TODAY THROUGH SUNDAY NIGHT/
UPR LOW LIFTING NE INTO SRN KS THIS MORNING EXPECTED TO MOVE ACROSS
SERN PORTION OF OUR CWA AS AN OPEN WAVE WITH A STRONG REMNANT VORT
MAX THIS EVE. DECENT FORCING ASSOCIATED WITH THIS FEATURE SHOULD BE
SUFFICIENT FOR SOME PRECIP IN OUR AREA... THOUGH GIVEN LACK OF LOW
LEVEL MOISTURE WITH GULF CLOSED OFF... EXPECT PRECIP WILL BE
SHOWERY... WITH GREATEST COVERAGE ACROSS THE NWRN 1/3 OF CWA WHICH
WILL BE IN DEFORMATION ZONE TO NW OF VORT MAX TRACK. COLD POCKET OF
AIR ASSOCIATED WITH THE UPR LOW/SHRTWV... WITH ASSIST FROM LOW
LEVEL EVAPORATIONAL COOLING... SHOULD RESULT IN SNOW AS MAIN
PRECIP TYPE THIS EVE. AS THIS SYSTEM MOVES EAST OF THE AREA
OVERNIGHT... A SECOND SHRTWV... CURRENTLY DROPPING SE INTO THE NRN
PLAINS... WILL MOVE THROUGH OUR AREA AROUND 12Z SUNDAY... WHILE A
THIRD STRONG VORT MAX FARTHER TO THE NW... EXPECTED TO MOVE ACROSS
THE CWA DURING THE DAY SUNDAY. COMBINATION OF THESE TWO SHRTWVS
SHOULD CAUSE WK SFC LOW OVER ND THIS MORNING TO GRDLY
INTENSIFY/DEEPEN AS IT MOVES ACROSS THE GRTLKS TONIGHT AND SUNDAY.
BEST FORCING IN OUR AREA EXPECTED TO ACCOMPANY FIRST SYSTEM THIS
EVE... BUT SOME LIFT SHOULD ALSO ACCOMPANY LADDER SYSTEMS LATE
TONIGHT AND SUNDAY. PERIOD OF MID LEVEL DRYING BEHIND FIRST SHRTWV
LATE TONIGHT COMBINED WITH INCREASING LOW LEVEL MOISTURE AND WK
WAA MAY ALLOW FOR SOME FREEZING DRIZZLE OVERNIGHT INTO SUNDAY
MORNING BEFORE MID LEVEL MOISTURE AND COOLER TEMPS ALOFT ARRIVE
SUNDAY WITH THE NRN STREAM SHRTWVS. THIS SCENARIO ALREADY PRETTY
WELL COVERED IN GOING FCST. MAIN CHANGE WAS TO BUMP UP POPS TO
LIKELY ACROSS NWRN 1/3 WHERE SNOW ACCUM AROUND AN INCH EXPECTED
THIS EVE. POTENTIAL FOR SOME ICY SURFACES DUE TO FREEZING DRIZZLE
OVERNIGHT AND SUNDAY MORNING... WILL CONT TO MENTION IN HWO AS
CONFIDENCE TOO LOW TO HEADLINE IN FCST ATTM. SKIES EXPECTED TO
CLEAR SUNDAY NIGHT AS A STRONG RIDGING MOVES INTO THE AREA. GOOD
RADIATIONAL COOLING CONDITIONS DESPITE WARMING ALOFT SHOULD ALLOW
TEMPS TO FALL INTO THE TEENS THIS PERIOD. OTRWS NO SGFNT CHANGE TO
MOS TEMPS WITH HIGHS TODAY AND SUNDAY EXPECTED IN THE L-M30S AND
LOWS TONIGHT IN THE U20S/L30S.
LONG TERM...MONDAY THROUGH FRIDAY
MID/UPPER LEVEL RIDGING WILL QUICKLY BUILD OVER THE REGION ON MONDAY
WITH DEEP SOUTHWEST FLOW IN PLACE BY MONDAY EVENING. 925MB TEMPS
CLIMB TO ALMOST 3C BY THIS TIME BUT AS HAS BEEN NOTED...SURFACE
TEMPS WILL NOT REFLECT THIS WARM AIR ALOFT WITH RESIDUAL SNOWPACK
PROMOTING A STRONG INVERSION. WAS INITIALLY CONCERNED ABOUT STRATUS
DEVELOPMENT BENEATH THE INVERSION BUT STRENGTH OF AVA AND ASSOCIATED
SUBSIDENCE COUPLED WITH VERY DRY AIR UPSTREAM SHOULD LEAD TO A
MOSTLY SUNNY DAY. AFTERNOON TEMPS LOOK TO REMAIN CAPPED IN THE LOW
30S THOUGH...SIMILAR TO LATEST MOS GUIDANCE AND INHERITED FORECAST.
TEMPS WILL SLOWLY MODERATE TUESDAY AND WEDNESDAY WITH CONTINUED WAA
AND A DECAYING SNOWPACK. EXPECT HIGHS IN THE UPPER 30S TO LOW 40S
WITH LOWS IN THE UPPER 20S TO LOW 30S.
CONFIDENCE IN TIMING OF PRECIP POTENTIAL REMAINS LOW BUT THERE ARE
HINTS OF A DEVELOPING CONSENSUS IN THE LATEST 00Z GUIDANCE. 00Z GFS
HAS TRENDED SHARPLY TO THE ECMWF SOLUTION IN SHOWING A CUTOFF UPPER
LOW OVER THE SOUTHWEST CONUS. NEW GFS STILL SPREADS SOME PRECIP OVER
OUR AREA ON WEDNESDAY BUT THIS IS ASSOCIATED WITH A PASSING NORTHERN
STREAM SHORTWAVE COUPLED WITH SOME WARM/MOIST AIR ADVECTION AHEAD OF
THE MAIN SYSTEM TO THE SOUTHWEST. THE MAIN SOUTHERN STREAM PV
ANOMALY DOESNT PASS OVERHEAD UNTIL THURSDAY...SIMILAR TO THE
LONGSTANDING EURO SOLUTION. THIS RAISES CONFIDENCE THAT WEDNESDAY
NIGHT/THURSDAY WILL BE THE BEST CHANCE FOR PRECIP. WILL KEEP EARLY
WEDNESDAY PERIOD DRY GIVEN PREFERENCE FOR THE MORE ZONAL/WEAKER
NORTHERN STREAM WAVE DEPICTED IN THE ECMWF. AS PREVIOUSLY
STATED...CANT RULE OUT A BRIEF MIX AT THE ONSET BUT PTYPES LOOK TO
BE ALMOST ALL RAIN.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SHORT TERM...JT
LONG TERM...AGD
AVIATION...FISHER
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
255 PM CST FRI JAN 4 2013
...UPDATED SYNOPSIS AND SHORT TERM DISCUSSION...
.SYNOPSIS...
ISSUED AT 254 PM CST FRI JAN 4 2013
THE 12Z UPPER AIR ANALYSIS SHOWED A CLOSED LOW AT 500 MB SPINNING
OVER NEW MEXICO THIS MORNING. THE ANALYSIS SHOWS THAT THIS SYSTEM
DOES NOT HAVE A LOT OF MOISTURE TO WORK WITH BUT SATELLITE IMAGERY
SHOWED MID AND HIGH LEVEL CLOUDINESS AHEAD OF THIS SYSTEM SPREADING
UP TOWARD SOUTHWEST KANSAS THIS AFTERNOON. IN THE LOWER LEVELS, A
RIDGE OF HIGH PRESSURE AT 850 MB EXTENDED FROM SOUTHEAST TEXAS BACK
INTO THE FOUR CORNERS REGION. AT THE SURFACE, A LOW PRESSURE TROUGH
WAS SLOWLY DEEPENING OVER EASTERN COLORADO. SURFACE DEWPOINTS WERE
GENERALLY IN THE TEENS OVER SOUTHWEST KANSAS WHILE FARTHER SOUTH,
OVER THE TEXAS PANHANDLE INTO WESTERN OKLAHOMA, DEWPOINTS WERE IN
THE LOWER TO MIDDLE 20S.
&&
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 254 PM CST FRI JAN 4 2013
THE UPPER LOW IS PROGGED BY THE MODELS TO MOVE FROM NEW MEXICO THIS
AFTERNOON THROUGH THE TEXAS PANHANDLE INTO EASTERN KANSAS BY
SATURDAY AFTERNOON. MODEL SOUNDINGS MOISTEN UP IN THE MID LEVELS
ACROSS SOUTH CENTRAL KANSAS THIS EVENING AND START TO MOISTEN
DOWNWARD WITH TIME. THE MODELS CONTINUE TO BE SKIMPY ON QPF WITH
THIS SYSTEM WHICH MAKES SENSE GIVEN THE LIMITED MOISTURE. THINK
THAT THERE COULD AT LEAST BE SOME FLURRIES FOR A PERIOD OF TIME
TONIGHT AND HAVE ADDED THAT TO THE GRIDS IN SOUTH CENTRAL KANSAS.
SURFACE WINDS WERE GRADUALLY VEERING WITH TIME THIS AFTERNOON AS THE
EASTERN COLORADO TROUGH DEEPENS IN ADVANCE OF THE UPPER WAVE. THIS
WILL ALLOW WEAK LOW LEVEL MOIST ADVECTION TO OCCUR OVER SOUTHWEST
KANSAS THIS EVENING. WITH THE MOISTURE RIDING UP OVER SNOW COVERED
GROUND, WE SHOULD SEE SOME FOG DEVELOP LATER THIS EVENING AND
CONTINUING THROUGH TONIGHT. MOS OUTPUT IS NOT INDICATING ANY
REDUCTION IN VISIBILITY AT ALL TONIGHT AND THE HRRR MODEL DOES NOT
INDICATE MUCH EITHER BEFORE 08Z. THE SREF PROBABILITIES DO SHOW SOME
INCREASED CHANCES FOR FOG SO WILL CONTINUE THE TREND OF SOME AREAS
OF FOG DEVELOPING. WILL ALSO START THE AREAS OF FOG FARTHER WEST
TOWARD GARDEN CITY AND SYRACUSE LATE THIS EVENING. FOR NOW WILL
HOLD OFF ON ANY HEADLINES AND LET THE NEXT SHIFT MAKE THAT
ASSESSMENT.
ON SATURDAY THE ANY LINGERING FOG IN THE EARLY MORNING SHOULD
DISSIPATE OR MOVE EAST OUT OF CENTRAL KANSAS AS THE SURFACE TROUGH
CONTINUES EAST. THE REMAINDER OF THE DAY SHOULD SEE MAINLY SUNNY
SKIES. WITH A LITTLE BETTER MIXING THAN TODAY, HIGH TEMPERATURES
SHOULD BE ABLE TO CLIMB INTO THE 30S OVER THE SNOW COVERED AREAS
WITH LOWER TO MIDDLE 40S IN SOUTH CENTRAL KANSAS WHERE THE SNOW HAS
MELTED.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 227 PM CST FRI JAN 4 2013
A WEAK, UPPER LEVEL HIGH PRESSURE RIDGE OVER THE PLAINS SUNDAY AND
INTO MONDAY WILL START TO BREAK DOWN BY LATE TUESDAY, AS A LARGE
UPPER LEVEL LOW PRESSURE SYSTEM APPROACHES FROM THE SOUTHWEST.
BOTH SUNDAY AND MONDAY WILL BE WARMER THAN IT HAS BEEN RECENTLY,
AND PLENTY OF SUNSHINE SHOULD HELP MELT MORE OF THE SNOW COVER.
HIGHS SUNDAY, MONDAY AND TUESDAY WILL RANGE FROM AROUND THE 40F
DEGREE NORTH OF THE I-70, TO THE MID TO UPPER 40S ALONG AND NEAR
THE OKLAHOMA BORDER. THEN ON TUESDAY NIGHT, SYNOPTIC SCALE LIFT
WILL RESULT FROM THE CLOSED LOW APPROACHING FROM THE SOUTHWEST.
MOISTURE WILL BE DEEPENING AND ADVECTING NORTH INTO SOUTHWESTERN
KANSAS, AND ESPECIALLY SOUTH CENTRAL KANSAS. THAT UPPER SYSTEM
WILL CONTINUE TO MARCH INTO THE TEXAS PANHANDLE BY 09/18Z OR WED
AFTERNOON, WHERE IT WILL THEN BEGIN TO LIFT NORTHEAST AND START TO
OPEN UP AS A WAVE, AT THE SAME TIME. AS FOR PRECIPITATION, THE
GOING 20 TO 30 PERCENT OF PRECIPITATION CHANCES, BASICALLY
SOUTHEAST OF A LIBERAL TO PRATT LINE, THROUGH WED/12Z SEEM
REASONABLE. THEN AS THE UPPER LOW LIFTS NORTHEAST LATE WEDNESDAY
INTO EASTERN KANSAS, 20(WEST) TO 35 (EAST) PRECIPITATION CHANCES
WEDNESDAY AFTERNOON AND NIGHT ACROSS ALL OF SOUTHWESTERN KANSAS
ALSO SEEM APPROPRIATE. PRECIPITATION TYPE WILL VARY FROM RAIN OR
SNOW IN THE DAY TIMES AND LIGHT SNOW IN THE NIGHT TIMES. AS THE
UPPER SYSTEM LIFTS OUT WEDNESDAY NIGHT, IT SHOULD ACCELERATE, AND
CHANCES FOR PRECIPITATION WILL QUICKLY END LATE WEDNESDAY NIGHT OR
VERY EARLY THURSDAY MORNING. AS THIS OCCURS, THERE WILL BE
CLEARING AND COOLING THURSDAY. A LITTLE WRAP-AROUND COLD AIR WILL
FILTER BACK INTO THE SOUTHWESTERN KANSAS FRIDAY, AND A LITTLE
LIGHT SNOW MAY DEVELOP. LOWER 20 PERCENT CHANCES FOR LIGHT SNOW
EXIST FOR FRIDAY.
WEDNESDAY AND THURSDAY LOOK TO WARM INTO THE LOWER TO MIDDLE 40S
NORTH OF JETMORE, AND AROUND 50F DEGREES SOUTH OF THE JETMORE-DODGE
CITY AREAS. ON FRIDAY, IT WILL COOL OFF TO HIGHS IN THE 30S.
MINIMUM TEMPERATURES WILL START OUT COLD SATURDAY MORNING, IN THE
TEENS OVER THE SNOW PACKED AREAS NORTHWEST OF A WAKEENEY TO GARDEN
CITY TO ELKHART LINE, AND RANGE TO THE MID 20S IN THE COLDWATER AND
MEDICINE LODGE AREAS. MEDIUM RANGE MODELS WARM MINIMUMS TO AROUND
THE 20F DEGREE MARK IN THE SCOTT CITY AREA BY TUESDAY, AND TO NEAR
30F DEGREES IN THE PRATT AREA. THE SLIGHT WARMING TREND WILL EXTEND
INTO THURSDAY MORNING, WITH LOWS FROM THE MID 20S IN SYRACUSE AND
SCOTT CITY, RANGING TO THE LOWER 30S IN PRATT, KIOWA AND COLDWATER.
MINIMUMS FRIDAY WILL TURN COOLER FROM AROUND 20F DEGREES IN THE KEARNY
COUNTY AREA TO THE UPPER 20S IN THE BARBER COUNTY AREA. SATURDAY
MORNING (DAY 8) SHOULD BE EVEN COLDER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1139 AM CST FRI JAN 4 2013
AN UPPER LEVEL LOW PRESSURE SYSTEM OVER NEW MEXICO THIS MORNING
WILL MOVE NORTHEAST INTO EASTERN KANSAS BY MIDDAY SATURDAY. AS THE
SYSTEM APPROACHES, SOUTHWESTERLY WINDS WILL BECOME SOUTHERLY BY
THIS EVENING. THIS WILL BRING AN INCREASE IN LOW LEVEL MOISTURE
ACROSS CENTRAL AND SOUTHWEST KANSAS WHICH IS EXPECTED TO RESULT
IN AREAS OF FOG DEVELOPING LATE THIS EVENING. UNCERTAINTY REMAINS
AS TO HOW WIDESPREAD THE FOG WILL BE AND HOW LOW THE VISIBILITY
WILL BE SO FOR NOW WILL INDICATE MVFR VSBYS IN THE TAFS STARTING
AROUND 05Z-06Z AND CONTINUING UNTIL AROUND 12Z-13Z WHEN A SURFACE
TROUGH WILL PASS THROUGH SOUTHWEST KANSAS AND BRING IMPROVING
VISIBILITIES.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 16 38 16 43 / 0 0 0 0
GCK 14 36 13 42 / 0 0 0 0
EHA 14 41 16 45 / 0 0 0 0
LBL 16 39 14 45 / 0 0 0 0
HYS 15 35 16 37 / 0 0 0 0
P28 25 42 20 44 / 10 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GERARD
SHORT TERM...GERARD
LONG TERM...BURKE
AVIATION...GERARD
AREA FORECAST DISCUSSION
NWS JACKSON KY
135 PM EST FRI JAN 4 2013
.UPDATE...
ISSUED AT 136 PM EST FRI JAN 4 2013
SHORT WAVE IS MOSTLY THROUGH EASTERN KENTUCKY. IT ONLY PRODUCED SOME
TEMPORARY CLOUDS AS IS PASSED ACROSS THE AREA. UPDATED THE FORECAST
TO BETTER REFLECT CURRENT CONDITIONS AND MODEL TRENDS. NO ZONE
UPDATES WILL BE REQUIRED...HOWEVER UPDATES WERE SENT TO NDFD AND THE
POINT AND CLICK.
UPDATE ISSUED AT 1015 AM EST FRI JAN 4 2013
UPDATED THE FORECAST TO BETTER REFLECT MODEL TRENDS AND CURRENT
CONDITIONS. MAIN ADJUSTMENTS WERE FOR THE CLOUDS MOVING ACROSS THE
AREA AS A POTENT...BUT DRY...UPPER TROUGH MOVES ACROSS THE AREA THIS
AFTERNOON.
UPDATE ISSUED AT 742 AM EST FRI JAN 4 2013
HAVE UPDATED THE GRID DATABASE TO BLEND OBSERVED EARLY MORNING CLOUD
AND TEMPERATURE TRENDS INTO THE AFTERNOON FORECAST.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 240 AM EST FRI JAN 4 2013
STILL NO SIGNIFICANT SYSTEMS TO CONTEND WITH IN THE SHORT TERM...BUT
THERE ARE A COUPLE OF ANNOYING ITEMS.
THE FIRST OF THESE IS THE LOW CLOUD DECK WHICH HAS BEEN SLOWLY
SINKING SOUTH OVER THE OHIO VALLEY DURING THE NIGHT. THE NAM IS NOT
MUCH HELP...ONCE AGAIN DOING VERY POORLY HANDLING LOW LEVEL MOISTURE.
THE GFS AT LEAST KNEW THAT IT WAS THERE...BUT THE CLOUDS HAVE
PROGRESSED SOUTH DURING THE NIGHT A BIT MORE THAN THE GFS SHOWED. THE
RUC IS PERHAPS PERFORMING THE BEST...BUT IS ONLY AVAILABLE THROUGH
18Z FRIDAY. WILL USE THE RUC THROUGH ITS PERIOD OF AVAILABILITY...AND
FOLLOW UP WITH THE GFS TREND OF DRYING UP THE CLOUDS DURING THE LATE
AFTERNOON AND EARLY EVENING.
RIDGING BUILDING IN AT THE SURFACE AND ALOFT SHOULD BRING MAINLY
CLEAR SKIES TONIGHT INTO SATURDAY MORNING.
AN UPPER LOW CURRENTLY OVER THE SOUTHWEST CONUS IS EXPECTED TO BE
PICKED UP BY AN UPPER LEVEL NORTHERN STREAM TROUGH DROPPING INTO THE
NORTH CENTRAL CONUS ON SATURDAY. AS THE UPPER LOW HEADS NORTHEAST TO
THE OHIO VALLEY...WE WILL SEE MID AND UPPER LEVEL CLOUDS INCREASE.
VIRGA WILL EVENTUALLY WORK TO MOISTEN LOWER LEVELS...AND SOME LIGHT
PRECIP CAN NOT BE RULED OUT LATE SATURDAY OR SATURDAY EVENING.
HOWEVER...ABOUT THE TIME THE LOWER LEVELS MOISTEN...MID/UPPER LEVEL
DRYING IS FORECAST AS THE SYSTEM ALOFT DEPARTS. THIS WILL LEAVE A
NARROW WINDOW OF OPPORTUNITY FOR PRECIP...AND HAVE ONLY USED 20
PERCENT POPS. CONDITIONS LOOK MARGINAL FOR RAIN VERSUS SNOW.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 255 AM EST FRI JAN 4 2013
THE MODELS START OFF IN GOOD AGREEMENT AND REMAIN IN GOOD AGREEMENT
THROUGH TUESDAY. HOWEVER...STILL SIGNIFICANT TIMING ISSUES WITH THE
NEXT WEATHER MAKER TOWARDS THE MIDDLE OF NEXT WEEK...LEADING TO VERY
LOW CONFIDENCE AT THIS TIME.
STARTING OFF THE FORECAST ON SUNDAY...IT LOOKS LIKE A TRANQUIL
PERIOD OF WEATHER IS EXPECTED DURING THE DAY...BUT A FAST MOVING
CLIPPER WILL DROP SOUTHEAST AND PROVIDE A QUICK SHOT FOR SOME
ISOLATED SNOW SHOWERS TOWARDS 00Z MONDAY. MOISTURE REMAINS VERY
WEAK...BUT UPSLOPE FLOW COULD HELP GENERATE THE NEEDED LIFT FOR A
FEW SNOW SHOWERS. NOT ANTICIPATING ANY ACCUMULATIONS AT THIS TIME.
MID LEVEL RIDING WILL SPREAD INTO THE AREA BY DAYBREAK MONDAY...WITH
CLEAR SKIES RETURNING. THIS WILL YIELD ANOTHER COLD START TO THE
DAY...BUT WE SHOULD SEE A NICE RECOVERY UNDER SUNNY SKIES ON MONDAY.
AS THE HIGH PRESSURE RIDGE PUSHES EAST...RETURN FLOW WILL ALLOW FOR
A FAIRLY GOOD WARM UP FOR THE EARLY TO MIDDLE PORTIONS OF NEXT WEEK.
HIGHS TUESDAY...WEDNESDAY...AND THURSDAY COULD PUSH 50 OR EXCEED IT.
HOWEVER...THE BIG QUESTION REMAINS HOW FAST THE NEXT WEATHER SYSTEM
ARRIVES FROM THE DESERT SOUTHWEST. GFS HAS ACTUALLY SPED UP THE
SYSTEM EVEN MORE AND NOW BRINGS A FAIRLY ROBUST SHORTWAVE TROUGH
INTO THE OHIO RIVER VALLEY ON WEDNESDAY. THE 00Z ECMWF REMAINS MUCH
SLOWER WITH THE MAIN SYSTEM NOT ARRIVING UNTIL THURSDAY. THE GFS
ENSEMBLE MEMBERS REMAIN IN CONSIDERABLE DISAGREEMENT...SO PLAN TO
KEEP A BROAD PERIOD OF LOW POPS IN THE FORECAST FROM LATE TUESDAY
NIGHT THROUGH THURSDAY EVENING. WITH THE WARM AIR MASS IN PLACE...AND
NO COLD AIR WRAPPING INTO THIS SYSTEM...PRECIPITATION WILL REMAIN
RAIN.
REGARDLESS OF THE TIMING OF THIS SYSTEM...IT LOOKS LIKE DRIER
WEATHER SHOULD RETURN BY FRIDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 136 PM EST FRI JAN 4 2013
EXPECTING VFR THE ENTIRE PERIOD. WINDS WILL BE A LITTLE GUSTY THIS
AFTERNOON BUT THEN DIE DOWN. NEXT CHANCE FOR MVFR WILL BE SATURDAY
NIGHT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJ
SHORT TERM...HAL
LONG TERM....KAS
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
1019 AM EST FRI JAN 4 2013
.UPDATE...
ISSUED AT 1015 AM EST FRI JAN 4 2013
UPDATED THE FORECAST TO BETTER REFLECT MODEL TRENDS AND CURRENT
CONDITIONS. MAIN ADJUSTMENTS WERE FOR THE CLOUDS MOVING ACROSS THE
AREA AS A POTENT...BUT DRY...UPPER TROUGH MOVES ACROSS THE AREA THIS
AFTERNOON.
UPDATE ISSUED AT 742 AM EST FRI JAN 4 2013
HAVE UPDATED THE GRID DATABASE TO BLEND OBSERVED EARLY MORNING CLOUD
AND TEMPERATURE TRENDS INTO THE AFTERNOON FORECAST.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 240 AM EST FRI JAN 4 2013
STILL NO SIGNIFICANT SYSTEMS TO CONTEND WITH IN THE SHORT TERM...BUT
THERE ARE A COUPLE OF ANNOYING ITEMS.
THE FIRST OF THESE IS THE LOW CLOUD DECK WHICH HAS BEEN SLOWLY
SINKING SOUTH OVER THE OHIO VALLEY DURING THE NIGHT. THE NAM IS NOT
MUCH HELP...ONCE AGAIN DOING VERY POORLY HANDLING LOW LEVEL MOISTURE.
THE GFS AT LEAST KNEW THAT IT WAS THERE...BUT THE CLOUDS HAVE
PROGRESSED SOUTH DURING THE NIGHT A BIT MORE THAN THE GFS SHOWED. THE
RUC IS PERHAPS PERFORMING THE BEST...BUT IS ONLY AVAILABLE THROUGH
18Z FRIDAY. WILL USE THE RUC THROUGH ITS PERIOD OF AVAILABILITY...AND
FOLLOW UP WITH THE GFS TREND OF DRYING UP THE CLOUDS DURING THE LATE
AFTERNOON AND EARLY EVENING.
RIDGING BUILDING IN AT THE SURFACE AND ALOFT SHOULD BRING MAINLY
CLEAR SKIES TONIGHT INTO SATURDAY MORNING.
AN UPPER LOW CURRENTLY OVER THE SOUTHWEST CONUS IS EXPECTED TO BE
PICKED UP BY AN UPPER LEVEL NORTHERN STREAM TROUGH DROPPING INTO THE
NORTH CENTRAL CONUS ON SATURDAY. AS THE UPPER LOW HEADS NORTHEAST TO
THE OHIO VALLEY...WE WILL SEE MID AND UPPER LEVEL CLOUDS INCREASE.
VIRGA WILL EVENTUALLY WORK TO MOISTEN LOWER LEVELS...AND SOME LIGHT
PRECIP CAN NOT BE RULED OUT LATE SATURDAY OR SATURDAY EVENING.
HOWEVER...ABOUT THE TIME THE LOWER LEVELS MOISTEN...MID/UPPER LEVEL
DRYING IS FORECAST AS THE SYSTEM ALOFT DEPARTS. THIS WILL LEAVE A
NARROW WINDOW OF OPPORTUNITY FOR PRECIP...AND HAVE ONLY USED 20
PERCENT POPS. CONDITIONS LOOK MARGINAL FOR RAIN VERSUS SNOW.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 255 AM EST FRI JAN 4 2013
THE MODELS START OFF IN GOOD AGREEMENT AND REMAIN IN GOOD AGREEMENT
THROUGH TUESDAY. HOWEVER...STILL SIGNIFICANT TIMING ISSUES WITH THE
NEXT WEATHER MAKER TOWARDS THE MIDDLE OF NEXT WEEK...LEADING TO VERY
LOW CONFIDENCE AT THIS TIME.
STARTING OFF THE FORECAST ON SUNDAY...IT LOOKS LIKE A TRANQUIL
PERIOD OF WEATHER IS EXPECTED DURING THE DAY...BUT A FAST MOVING
CLIPPER WILL DROP SOUTHEAST AND PROVIDE A QUICK SHOT FOR SOME
ISOLATED SNOW SHOWERS TOWARDS 00Z MONDAY. MOISTURE REMAINS VERY
WEAK...BUT UPSLOPE FLOW COULD HELP GENERATE THE NEEDED LIFT FOR A
FEW SNOW SHOWERS. NOT ANTICIPATING ANY ACCUMULATIONS AT THIS TIME.
MID LEVEL RIDING WILL SPREAD INTO THE AREA BY DAYBREAK MONDAY...WITH
CLEAR SKIES RETURNING. THIS WILL YIELD ANOTHER COLD START TO THE
DAY...BUT WE SHOULD SEE A NICE RECOVERY UNDER SUNNY SKIES ON MONDAY.
AS THE HIGH PRESSURE RIDGE PUSHES EAST...RETURN FLOW WILL ALLOW FOR
A FAIRLY GOOD WARM UP FOR THE EARLY TO MIDDLE PORTIONS OF NEXT WEEK.
HIGHS TUESDAY...WEDNESDAY...AND THURSDAY COULD PUSH 50 OR EXCEED IT.
HOWEVER...THE BIG QUESTION REMAINS HOW FAST THE NEXT WEATHER SYSTEM
ARRIVES FROM THE DESERT SOUTHWEST. GFS HAS ACTUALLY SPED UP THE
SYSTEM EVEN MORE AND NOW BRINGS A FAIRLY ROBUST SHORTWAVE TROUGH
INTO THE OHIO RIVER VALLEY ON WEDNESDAY. THE 00Z ECMWF REMAINS MUCH
SLOWER WITH THE MAIN SYSTEM NOT ARRIVING UNTIL THURSDAY. THE GFS
ENSEMBLE MEMBERS REMAIN IN CONSIDERABLE DISAGREEMENT...SO PLAN TO
KEEP A BROAD PERIOD OF LOW POPS IN THE FORECAST FROM LATE TUESDAY
NIGHT THROUGH THURSDAY EVENING. WITH THE WARM AIR MASS IN PLACE...AND
NO COLD AIR WRAPPING INTO THIS SYSTEM...PRECIPITATION WILL REMAIN
RAIN.
REGARDLESS OF THE TIMING OF THIS SYSTEM...IT LOOKS LIKE DRIER
WEATHER SHOULD RETURN BY FRIDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 606 AM EST FRI JAN 4 2013
A DECK OF CLOUDS IN THE RANGE OF 2500-3500 FEET WILL MOVE OVER THE
NORTHERN AND EASTERN PORTIONS OF THE FORECAST AREA THIS MORNING...AND
THEN THIN OUT TO A SCATTERED LAYER IN THE AFTERNOON. THIS WILL BRING
A PERIOD OF MVFR TO MANY LOCATIONS NORTH OF A LINE FROM SOMERSET TO
PIKEVILLE. WEST WINDS WILL KICK IN DURING THE DAY...ESPECIALLY NEAR
AND NORTH OF INTERSTATE 64...WHERE GUSTS OF 20-25 KNOTS ARE EXPECTED.
WINDS WILL DIE DOWN EARLY THIS EVENING AND SKIES WILL CLEAR...LEAVING
VFR AND LIGHT WINDS THROUGH THE REMAINDER OF THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...RAY
SHORT TERM...HAL
LONG TERM....KAS
AVIATION...HAL
AREA FORECAST DISCUSSION...CORRECTED
NWS JACKSON KY
743 AM EST FRI JAN 4 2013
.UPDATE...
ISSUED AT 742 AM EST FRI JAN 4 2013
HAVE UPDATED THE GRID DATABASE TO BLEND OBSERVED EARLY MORNING CLOUD
AND TEMPERATURE TRENDS INTO THE AFTERNOON FORECAST.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 240 AM EST FRI JAN 4 2013
STILL NO SIGNIFICANT SYSTEMS TO CONTEND WITH IN THE SHORT TERM...BUT
THERE ARE A COUPLE OF ANNOYING ITEMS.
THE FIRST OF THESE IS THE LOW CLOUD DECK WHICH HAS BEEN SLOWLY
SINKING SOUTH OVER THE OHIO VALLEY DURING THE NIGHT. THE NAM IS NOT
MUCH HELP...ONCE AGAIN DOING VERY POORLY HANDLING LOW LEVEL MOISTURE.
THE GFS AT LEAST KNEW THAT IT WAS THERE...BUT THE CLOUDS HAVE
PROGRESSED SOUTH DURING THE NIGHT A BIT MORE THAN THE GFS SHOWED. THE
RUC IS PERHAPS PERFORMING THE BEST...BUT IS ONLY AVAILABLE THROUGH
18Z FRIDAY. WILL USE THE RUC THROUGH ITS PERIOD OF AVAILABILITY...AND
FOLLOW UP WITH THE GFS TREND OF DRYING UP THE CLOUDS DURING THE LATE
AFTERNOON AND EARLY EVENING.
RIDGING BUILDING IN AT THE SURFACE AND ALOFT SHOULD BRING MAINLY
CLEAR SKIES TONIGHT INTO SATURDAY MORNING.
AN UPPER LOW CURRENTLY OVER THE SOUTHWEST CONUS IS EXPECTED TO BE
PICKED UP BY AN UPPER LEVEL NORTHERN STREAM TROUGH DROPPING INTO THE
NORTH CENTRAL CONUS ON SATURDAY. AS THE UPPER LOW HEADS NORTHEAST TO
THE OHIO VALLEY...WE WILL SEE MID AND UPPER LEVEL CLOUDS INCREASE.
VIRGA WILL EVENTUALLY WORK TO MOISTEN LOWER LEVELS...AND SOME LIGHT
PRECIP CAN NOT BE RULED OUT LATE SATURDAY OR SATURDAY EVENING.
HOWEVER...ABOUT THE TIME THE LOWER LEVELS MOISTEN...MID/UPPER LEVEL
DRYING IS FORECAST AS THE SYSTEM ALOFT DEPARTS. THIS WILL LEAVE A
NARROW WINDOW OF OPPORTUNITY FOR PRECIP...AND HAVE ONLY USED 20
PERCENT POPS. CONDITIONS LOOK MARGINAL FOR RAIN VERSUS SNOW.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 255 AM EST FRI JAN 4 2013
THE MODELS START OFF IN GOOD AGREEMENT AND REMAIN IN GOOD AGREEMENT
THROUGH TUESDAY. HOWEVER...STILL SIGNIFICANT TIMING ISSUES WITH THE
NEXT WEATHER MAKER TOWARDS THE MIDDLE OF NEXT WEEK...LEADING TO VERY
LOW CONFIDENCE AT THIS TIME.
STARTING OFF THE FORECAST ON SUNDAY...IT LOOKS LIKE A TRANQUIL
PERIOD OF WEATHER IS EXPECTED DURING THE DAY...BUT A FAST MOVING
CLIPPER WILL DROP SOUTHEAST AND PROVIDE A QUICK SHOT FOR SOME
ISOLATED SNOW SHOWERS TOWARDS 00Z MONDAY. MOISTURE REMAINS VERY
WEAK...BUT UPSLOPE FLOW COULD HELP GENERATE THE NEEDED LIFT FOR A
FEW SNOW SHOWERS. NOT ANTICIPATING ANY ACCUMULATIONS AT THIS TIME.
MID LEVEL RIDING WILL SPREAD INTO THE AREA BY DAYBREAK MONDAY...WITH
CLEAR SKIES RETURNING. THIS WILL YIELD ANOTHER COLD START TO THE
DAY...BUT WE SHOULD SEE A NICE RECOVERY UNDER SUNNY SKIES ON MONDAY.
AS THE HIGH PRESSURE RIDGE PUSHES EAST...RETURN FLOW WILL ALLOW FOR
A FAIRLY GOOD WARM UP FOR THE EARLY TO MIDDLE PORTIONS OF NEXT WEEK.
HIGHS TUESDAY...WEDNESDAY...AND THURSDAY COULD PUSH 50 OR EXCEED IT.
HOWEVER...THE BIG QUESTION REMAINS HOW FAST THE NEXT WEATHER SYSTEM
ARRIVES FROM THE DESERT SOUTHWEST. GFS HAS ACTUALLY SPED UP THE
SYSTEM EVEN MORE AND NOW BRINGS A FAIRLY ROBUST SHORTWAVE TROUGH
INTO THE OHIO RIVER VALLEY ON WEDNESDAY. THE 00Z ECMWF REMAINS MUCH
SLOWER WITH THE MAIN SYSTEM NOT ARRIVING UNTIL THURSDAY. THE GFS
ENSEMBLE MEMBERS REMAIN IN CONSIDERABLE DISAGREEMENT...SO PLAN TO
KEEP A BROAD PERIOD OF LOW POPS IN THE FORECAST FROM LATE TUESDAY
NIGHT THROUGH THURSDAY EVENING. WITH THE WARM AIR MASS IN PLACE...AND
NO COLD AIR WRAPPING INTO THIS SYSTEM...PRECIPITATION WILL REMAIN
RAIN.
REGARDLESS OF THE TIMING OF THIS SYSTEM...IT LOOKS LIKE DRIER
WEATHER SHOULD RETURN BY FRIDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 606 AM EST FRI JAN 4 2013
A DECK OF CLOUDS IN THE RANGE OF 2500-3500 FEET WILL MOVE OVER THE
NORTHERN AND EASTERN PORTIONS OF THE FORECAST AREA THIS MORNING...AND
THEN THIN OUT TO A SCATTERED LAYER IN THE AFTERNOON. THIS WILL BRING
A PERIOD OF MVFR TO MANY LOCATIONS NORTH OF A LINE FROM SOMERSET TO
PIKEVILLE. WEST WINDS WILL KICK IN DURING THE DAY...ESPECIALLY NEAR
AND NORTH OF INTERSTATE 64...WHERE GUSTS OF 20-25 KNOTS ARE EXPECTED.
WINDS WILL DIE DOWN EARLY THIS EVENING AND SKIES WILL CLEAR...LEAVING
VFR AND LIGHT WINDS THROUGH THE REMAINDER OF THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...HAL
LONG TERM....KAS
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
742 AM EST FRI JAN 4 2013
.UPDATE...
ISSUED AT 742 AM EST FRI JAN 4 2013
HAVE UPDATED THE GRID DATABASE TO BLEND OBSERVED EARLY MORNING CLOUD
AND TEMPERATURE TRENDS INTO THE AFTERNOON FORECAST.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 240 AM EST FRI JAN 4 2013
STILL NO SIGNIFICANT SYSTEMS TO CONTEND WITH IN THE SHORT TERM...BUT
THERE AREA A COUPLE OF ANNOYING ITEMS.
THE FIRST OF THESE IS THE LOW CLOUD DECK WHICH HAS BEEN SLOWLY
SINKING SOUTH OVER THE OHIO VALLEY DURING THE NIGHT. THE NAM IS NOT
MUCH HELP...ONCE AGAIN DOING VERY POORLY HANDLING LOW LEVEL MOISTURE.
THE GFS AT LEAST KNEW THAT IT WAS THERE...BUT THE CLOUDS HAVE
PROGRESSED SOUTH DURING THE NIGHT A BIT MORE THAN THE GFS SHOWED. THE
RUC IS PERHAPS PERFORMING THE BEST...BUT IS ONLY AVAILABLE THROUGH
18Z FRIDAY. WILL USE THE RUC THROUGH ITS PERIOD OF AVAILABILITY...AND
FOLLOW UP WITH THE GFS TREND OF DRYING UP THE CLOUDS DURING THE LATE
AFTERNOON AND EARLY EVENING.
RIDGING BUILDING IN AT THE SURFACE AND ALOFT SHOULD BRING MAINLY
CLEAR SKIES TONIGHT INTO SATURDAY MORNING.
AN UPPER LOW CURRENTLY OVER THE SOUTHWEST CONUS IS EXPECTED TO BE
PICKED UP BY AN UPPER LEVEL NORTHERN STREAM TROUGH DROPPING INTO THE
NORTH CENTRAL CONUS ON SATURDAY. AS THE UPPER LOW HEADS NORTHEAST TO
THE OHIO VALLEY...WE WILL SEE MID AND UPPER LEVEL CLOUDS INCREASE.
VIRGA WILL EVENTUALLY WORK TO MOISTEN LOWER LEVELS...AND SOME LIGHT
PRECIP CAN NOT BE RULED OUT LATE SATURDAY OR SATURDAY EVENING.
HOWEVER...ABOUT THE TIME THE LOWER LEVELS MOISTEN...MID/UPPER LEVEL
DRYING IS FORECAST AS THE SYSTEM ALOFT DEPARTS. THIS WILL LEAVE A
NARROW WINDOW OF OPPORTUNITY FOR PRECIP...AND HAVE ONLY USED 20
PERCENT POPS. CONDITIONS LOOK MARGINAL FOR RAIN VERSUS SNOW.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 255 AM EST FRI JAN 4 2013
THE MODELS START OFF IN GOOD AGREEMENT AND REMAIN IN GOOD AGREEMENT
THROUGH TUESDAY. HOWEVER...STILL SIGNIFICANT TIMING ISSUES WITH THE
NEXT WEATHER MAKER TOWARDS THE MIDDLE OF NEXT WEEK...LEADING TO VERY
LOW CONFIDENCE AT THIS TIME.
STARTING OFF THE FORECAST ON SUNDAY...IT LOOKS LIKE A TRANQUIL
PERIOD OF WEATHER IS EXPECTED DURING THE DAY...BUT A FAST MOVING
CLIPPER WILL DROP SOUTHEAST AND PROVIDE A QUICK SHOT FOR SOME
ISOLATED SNOW SHOWERS TOWARDS 00Z MONDAY. MOISTURE REMAINS VERY
WEAK...BUT UPSLOPE FLOW COULD HELP GENERATE THE NEEDED LIFT FOR A
FEW SNOW SHOWERS. NOT ANTICIPATING ANY ACCUMULATIONS AT THIS TIME.
MID LEVEL RIDING WILL SPREAD INTO THE AREA BY DAYBREAK MONDAY...WITH
CLEAR SKIES RETURNING. THIS WILL YIELD ANOTHER COLD START TO THE
DAY...BUT WE SHOULD SEE A NICE RECOVERY UNDER SUNNY SKIES ON MONDAY.
AS THE HIGH PRESSURE RIDGE PUSHES EAST...RETURN FLOW WILL ALLOW FOR
A FAIRLY GOOD WARM UP FOR THE EARLY TO MIDDLE PORTIONS OF NEXT WEEK.
HIGHS TUESDAY...WEDNESDAY...AND THURSDAY COULD PUSH 50 OR EXCEED IT.
HOWEVER...THE BIG QUESTION REMAINS HOW FAST THE NEXT WEATHER SYSTEM
ARRIVES FROM THE DESERT SOUTHWEST. GFS HAS ACTUALLY SPED UP THE
SYSTEM EVEN MORE AND NOW BRINGS A FAIRLY ROBUST SHORTWAVE TROUGH
INTO THE OHIO RIVER VALLEY ON WEDNESDAY. THE 00Z ECMWF REMAINS MUCH
SLOWER WITH THE MAIN SYSTEM NOT ARRIVING UNTIL THURSDAY. THE GFS
ENSEMBLE MEMBERS REMAIN IN CONSIDERABLE DISAGREEMENT...SO PLAN TO
KEEP A BROAD PERIOD OF LOW POPS IN THE FORECAST FROM LATE TUESDAY
NIGHT THROUGH THURSDAY EVENING. WITH THE WARM AIR MASS IN PLACE...AND
NO COLD AIR WRAPPING INTO THIS SYSTEM...PRECIPITATION WILL REMAIN
RAIN.
REGARDLESS OF THE TIMING OF THIS SYSTEM...IT LOOKS LIKE DRIER
WEATHER SHOULD RETURN BY FRIDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 606 AM EST FRI JAN 4 2013
A DECK OF CLOUDS IN THE RANGE OF 2500-3500 FEET WILL MOVE OVER THE
NORTHERN AND EASTERN PORTIONS OF THE FORECAST AREA THIS MORNING...AND
THEN THIN OUT TO A SCATTERED LAYER IN THE AFTERNOON. THIS WILL BRING
A PERIOD OF MVFR TO MANY LOCATIONS NORTH OF A LINE FROM SOMERSET TO
PIKEVILLE. WEST WINDS WILL KICK IN DURING THE DAY...ESPECIALLY NEAR
AND NORTH OF INTERSTATE 64...WHERE GUSTS OF 20-25 KNOTS ARE EXPECTED.
WINDS WILL DIE DOWN EARLY THIS EVENING AND SKIES WILL CLEAR...LEAVING
VFR AND LIGHT WINDS THROUGH THE REMAINDER OF THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...HAL
LONG TERM....KAS
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
606 AM EST FRI JAN 4 2013
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 240 AM EST FRI JAN 4 2013
STILL NO SIGNIFICANT SYSTEMS TO CONTEND WITH IN THE SHORT TERM...BUT
THERE AREA A COUPLE OF ANNOYING ITEMS.
THE FIRST OF THESE IS THE LOW CLOUD DECK WHICH HAS BEEN SLOWLY
SINKING SOUTH OVER THE OHIO VALLEY DURING THE NIGHT. THE NAM IS NOT
MUCH HELP...ONCE AGAIN DOING VERY POORLY HANDLING LOW LEVEL MOISTURE.
THE GFS AT LEAST KNEW THAT IT WAS THERE...BUT THE CLOUDS HAVE
PROGRESSED SOUTH DURING THE NIGHT A BIT MORE THAN THE GFS SHOWED. THE
RUC IS PERHAPS PERFORMING THE BEST...BUT IS ONLY AVAILABLE THROUGH
18Z FRIDAY. WILL USE THE RUC THROUGH ITS PERIOD OF AVAILABILITY...AND
FOLLOW UP WITH THE GFS TREND OF DRYING UP THE CLOUDS DURING THE LATE
AFTERNOON AND EARLY EVENING.
RIDGING BUILDING IN AT THE SURFACE AND ALOFT SHOULD BRING MAINLY
CLEAR SKIES TONIGHT INTO SATURDAY MORNING.
AN UPPER LOW CURRENTLY OVER THE SOUTHWEST CONUS IS EXPECTED TO BE
PICKED UP BY AN UPPER LEVEL NORTHERN STREAM TROUGH DROPPING INTO THE
NORTH CENTRAL CONUS ON SATURDAY. AS THE UPPER LOW HEADS NORTHEAST TO
THE OHIO VALLEY...WE WILL SEE MID AND UPPER LEVEL CLOUDS INCREASE.
VIRGA WILL EVENTUALLY WORK TO MOISTEN LOWER LEVELS...AND SOME LIGHT
PRECIP CAN NOT BE RULED OUT LATE SATURDAY OR SATURDAY EVENING.
HOWEVER...ABOUT THE TIME THE LOWER LEVELS MOISTEN...MID/UPPER LEVEL
DRYING IS FORECAST AS THE SYSTEM ALOFT DEPARTS. THIS WILL LEAVE A
NARROW WINDOW OF OPPORTUNITY FOR PRECIP...AND HAVE ONLY USED 20
PERCENT POPS. CONDITIONS LOOK MARGINAL FOR RAIN VERSUS SNOW.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 255 AM EST FRI JAN 4 2013
THE MODELS START OFF IN GOOD AGREEMENT AND REMAIN IN GOOD AGREEMENT
THROUGH TUESDAY. HOWEVER...STILL SIGNIFICANT TIMING ISSUES WITH THE
NEXT WEATHER MAKER TOWARDS THE MIDDLE OF NEXT WEEK...LEADING TO VERY
LOW CONFIDENCE AT THIS TIME.
STARTING OFF THE FORECAST ON SUNDAY...IT LOOKS LIKE A TRANQUIL
PERIOD OF WEATHER IS EXPECTED DURING THE DAY...BUT A FAST MOVING
CLIPPER WILL DROP SOUTHEAST AND PROVIDE A QUICK SHOT FOR SOME
ISOLATED SNOW SHOWERS TOWARDS 00Z MONDAY. MOISTURE REMAINS VERY
WEAK...BUT UPSLOPE FLOW COULD HELP GENERATE THE NEEDED LIFT FOR A
FEW SNOW SHOWERS. NOT ANTICIPATING ANY ACCUMULATIONS AT THIS TIME.
MID LEVEL RIDING WILL SPREAD INTO THE AREA BY DAYBREAK MONDAY...WITH
CLEAR SKIES RETURNING. THIS WILL YIELD ANOTHER COLD START TO THE
DAY...BUT WE SHOULD SEE A NICE RECOVERY UNDER SUNNY SKIES ON MONDAY.
AS THE HIGH PRESSURE RIDGE PUSHES EAST...RETURN FLOW WILL ALLOW FOR
A FAIRLY GOOD WARM UP FOR THE EARLY TO MIDDLE PORTIONS OF NEXT WEEK.
HIGHS TUESDAY...WEDNESDAY...AND THURSDAY COULD PUSH 50 OR EXCEED IT.
HOWEVER...THE BIG QUESTION REMAINS HOW FAST THE NEXT WEATHER SYSTEM
ARRIVES FROM THE DESERT SOUTHWEST. GFS HAS ACTUALLY SPED UP THE
SYSTEM EVEN MORE AND NOW BRINGS A FAIRLY ROBUST SHORTWAVE TROUGH
INTO THE OHIO RIVER VALLEY ON WEDNESDAY. THE 00Z ECMWF REMAINS MUCH
SLOWER WITH THE MAIN SYSTEM NOT ARRIVING UNTIL THURSDAY. THE GFS
ENSEMBLE MEMBERS REMAIN IN CONSIDERABLE DISAGREEMENT...SO PLAN TO
KEEP A BROAD PERIOD OF LOW POPS IN THE FORECAST FROM LATE TUESDAY
NIGHT THROUGH THURSDAY EVENING. WITH THE WARM AIR MASS IN PLACE...AND
NO COLD AIR WRAPPING INTO THIS SYSTEM...PRECIPITATION WILL REMAIN
RAIN.
REGARDLESS OF THE TIMING OF THIS SYSTEM...IT LOOKS LIKE DRIER
WEATHER SHOULD RETURN BY FRIDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 606 AM EST FRI JAN 4 2013
A DECK OF CLOUDS IN THE RANGE OF 2500-3500 FEET WILL MOVE OVER THE
NORTHERN AND EASTERN PORTIONS OF THE FORECAST AREA THIS MORNING...AND
THEN THIN OUT TO A SCATTERED LAYER IN THE AFTERNOON. THIS WILL BRING
A PERIOD OF MVFR TO MANY LOCATIONS NORTH OF A LINE FROM SOMERSET TO
PIKEVILLE. WEST WINDS WILL KICK IN DURING THE DAY...ESPECIALLY NEAR
AND NORTH OF INTERSTATE 64...WHERE GUSTS OF 20-25 KNOTS ARE EXPECTED.
WINDS WILL DIE DOWN EARLY THIS EVENING AND SKIES WILL CLEAR...LEAVING
VFR AND LIGHT WINDS THROUGH THE REMAINDER OF THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...HAL
LONG TERM....KAS
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
255 AM EST FRI JAN 4 2013
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 240 AM EST FRI JAN 4 2013
STILL NO SIGNIFICANT SYSTEMS TO CONTEND WITH IN THE SHORT TERM...BUT
THERE AREA A COUPLE OF ANNOYING ITEMS.
THE FIRST OF THESE IS THE LOW CLOUD DECK WHICH HAS BEEN SLOWLY
SINKING SOUTH OVER THE OHIO VALLEY DURING THE NIGHT. THE NAM IS NOT
MUCH HELP...ONCE AGAIN DOING VERY POORLY HANDLING LOW LEVEL MOISTURE.
THE GFS AT LEAST KNEW THAT IT WAS THERE...BUT THE CLOUDS HAVE
PROGRESSED SOUTH DURING THE NIGHT A BIT MORE THAN THE GFS SHOWED. THE
RUC IS PERHAPS PERFORMING THE BEST...BUT IS ONLY AVAILABLE THROUGH
18Z FRIDAY. WILL USE THE RUC THROUGH ITS PERIOD OF AVAILABILITY...AND
FOLLOW UP WITH THE GFS TREND OF DRYING UP THE CLOUDS DURING THE LATE
AFTERNOON AND EARLY EVENING.
RIDGING BUILDING IN AT THE SURFACE AND ALOFT SHOULD BRING MAINLY
CLEAR SKIES TONIGHT INTO SATURDAY MORNING.
AN UPPER LOW CURRENTLY OVER THE SOUTHWEST CONUS IS EXPECTED TO BE
PICKED UP BY AN UPPER LEVEL NORTHERN STREAM TROUGH DROPPING INTO THE
NORTH CENTRAL CONUS ON SATURDAY. AS THE UPPER LOW HEADS NORTHEAST TO
THE OHIO VALLEY...WE WILL SEE MID AND UPPER LEVEL CLOUDS INCREASE.
VIRGA WILL EVENTUALLY WORK TO MOISTEN LOWER LEVELS...AND SOME LIGHT
PRECIP CAN NOT BE RULED OUT LATE SATURDAY OR SATURDAY EVENING.
HOWEVER...ABOUT THE TIME THE LOWER LEVELS MOISTEN...MID/UPPER LEVEL
DRYING IS FORECAST AS THE SYSTEM ALOFT DEPARTS. THIS WILL LEAVE A
NARROW WINDOW OF OPPORTUNITY FOR PRECIP...AND HAVE ONLY USED 20
PERCENT POPS. CONDITIONS LOOK MARGINAL FOR RAIN VERSUS SNOW.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 255 AM EST FRI JAN 4 2013
THE MODELS START OFF IN GOOD AGREEMENT AND REMAIN IN GOOD AGREEMENT
THROUGH TUESDAY. HOWEVER...STILL SIGNIFICANT TIMING ISSUES WITH THE
NEXT WEATHER MAKER TOWARDS THE MIDDLE OF NEXT WEEK...LEADING TO VERY
LOW CONFIDENCE AT THIS TIME.
STARTING OFF THE FORECAST ON SUNDAY...IT LOOKS LIKE A TRANQUIL
PERIOD OF WEATHER IS EXPECTED DURING THE DAY...BUT A FAST MOVING
CLIPPER WILL DROP SOUTHEAST AND PROVIDE A QUICK SHOT FOR SOME
ISOLATED SNOW SHOWERS TOWARDS 00Z MONDAY. MOISTURE REMAINS VERY
WEAK...BUT UPSLOPE FLOW COULD HELP GENERATE THE NEEDED LIFT FOR A
FEW SNOW SHOWERS. NOT ANTICIPATED ANY ACCUMULATIONS AT THIS TIME.
MID LEVEL RIDING WILL SPREAD INTO THE AREA BY DAYBREAK MONDAY...WITH
CLEAR SKIES RETURNING. THIS WILL YIELD ANOTHER COLD START TO THE
DAY...BUT WE SHOULD SEE A NICE RECOVERY UNDER SUNNY SKIES ON MONDAY.
AS THE HIGH PRESSURE RIDGE PUSHES EAST...RETURN FLOW WILL ALLOW FOR
A FAIRLY GOOD WARM UP FOR THE EARLY TO MIDDLE PORTIONS OF NEXT WEEK.
HIGHS TUESDAY...WEDNESDAY...AND THURSDAY COULD PUSH 50 OR EXCEED IT.
HOWEVER...THE BIG QUESTION REMAINS HOW FAST THE NEXT WEATHER SYSTEM
ARRIVES FROM THE DESERT SOUTHWEST. GFS HAS ACTUALLY SPED UP THE
SYSTEM EVEN MORE AND NOW BRINGS A FAIRLY ROBUST SHORTWAVE TROUGH
INTO THE OHIO RIVER VALLEY ON WEDNESDAY. THE 00Z ECMWF REMAINS MUCH
SLOWER WITH THE MAIN SYSTEM NOT ARRIVING UNTIL THURSDAY. THE GFS
ENSEMBLE MEMBERS REMAIN IN CONSIDERABLE DISAGREEMENT...SO PLAN TO
KEEP A BROAD PERIOD OF LOW POPS IN THE FORECAST FROM LATE TUESDAY
NIGHT THROUGH THURSDAY EVENING. WITH THE WARM AIRMASS IN PLACE...AND
NO COLD AIR WRAPPING INTO THIS SYSTEM...PRECIPITATION WILL REMAIN ON
RAIN.
REGARDLESS OF THE TIMING OF THIS SYSTEM...IT LOOKS LIKE DRIER
WEATHER SHOULD RETURN BY FRIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 116 AM EST FRI JAN 4 2013
MOSTLY VFR IS EXPECTED THROUGH THE PERIOD...WITH WINDS OF 10 KT OR
LESS. A POSSIBLE EXCEPTION WILL BE IN THE NORTHERN END OF THE
FORECAST AREA AROUND FLEMINGSBURG...MOUNT STERLING...AND MOREHEAD...
WHERE MVFR CEILINGS MAY BE PRESENT AT TIMES THROUGH FRIDAY MORNING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...HAL
LONG TERM....KAS
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
241 AM EST FRI JAN 4 2013
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 240 AM EST FRI JAN 4 2013
STILL NO SIGNIFICANT SYSTEMS TO CONTEND WITH IN THE SHORT TERM...BUT
THERE AREA A COUPLE OF ANNOYING ITEMS.
THE FIRST OF THESE IS THE LOW CLOUD DECK WHICH HAS BEEN SLOWLY
SINKING SOUTH OVER THE OHIO VALLEY DURING THE NIGHT. THE NAM IS NOT
MUCH HELP...ONCE AGAIN DOING VERY POORLY HANDLING LOW LEVEL MOISTURE.
THE GFS AT LEAST KNEW THAT IT WAS THERE...BUT THE CLOUDS HAVE
PROGRESSED SOUTH DURING THE NIGHT A BIT MORE THAN THE GFS SHOWED. THE
RUC IS PERHAPS PERFORMING THE BEST...BUT IS ONLY AVAILABLE THROUGH
18Z FRIDAY. WILL USE THE RUC THROUGH ITS PERIOD OF AVAILABILITY...AND
FOLLOW UP WITH THE GFS TREND OF DRYING UP THE CLOUDS DURING THE LATE
AFTERNOON AND EARLY EVENING.
RIDGING BUILDING IN AT THE SURFACE AND ALOFT SHOULD BRING MAINLY
CLEAR SKIES TONIGHT INTO SATURDAY MORNING.
AN UPPER LOW CURRENTLY OVER THE SOUTHWEST CONUS IS EXPECTED TO BE
PICKED UP BY AN UPPER LEVEL NORTHERN STREAM TROUGH DROPPING INTO THE
NORTH CENTRAL CONUS ON SATURDAY. AS THE UPPER LOW HEADS NORTHEAST TO
THE OHIO VALLEY...WE WILL SEE MID AND UPPER LEVEL CLOUDS INCREASE.
VIRGA WILL EVENTUALLY WORK TO MOISTEN LOWER LEVELS...AND SOME LIGHT
PRECIP CAN NOT BE RULED OUT LATE SATURDAY OR SATURDAY EVENING.
HOWEVER...ABOUT THE TIME THE LOWER LEVELS MOISTEN...MID/UPPER LEVEL
DRYING IS FORECAST AS THE SYSTEM ALOFT DEPARTS. THIS WILL LEAVE A
NARROW WINDOW OF OPPORTUNITY FOR PRECIP...AND HAVE ONLY USED 20
PERCENT POPS. CONDITIONS LOOK MARGINAL FOR RAIN VERSUS SNOW.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 240 AM EST FRI JAN 4 2013
AN UPDATED LONG TERM DISCUSSION WILL BE ISSUED SHORTLY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 116 AM EST FRI JAN 4 2013
MOSTLY VFR IS EXPECTED THROUGH THE PERIOD...WITH WINDS OF 10 KT OR
LESS. A POSSIBLE EXCEPTION WILL BE IN THE NORTHERN END OF THE
FORECAST AREA AROUND FLEMINGSBURG...MOUNT STERLING...AND MOREHEAD...
WHERE MVFR CEILINGS MAY BE PRESENT AT TIMES THROUGH FRIDAY MORNING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...HAL
LONG TERM....GEOGERIAN
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
410 AM EST FRI JAN 4 2013
.SYNOPSIS...
SEASONABLY COLD WEATHER WILL CONTINUE INTO THE WEEKEND. A SERIES
OF DISTURBANCES WILL SPAWN THE NEXT CHANCE FOR SNOW SHOWERS ON
SATURDAY NIGHT AND SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STRATOCU BLANKET PERSISTS OVR THE UPR OH REGION THIS MRNG AS
SHRTWV...BEST EXHIBITED VIA MID LVL THERMAL TROF IN RAP MDL AND BY
IR SATELLITE PICS...CONTS EWD PROGRESS. NO MORE THAN FLURRIES OR
AN ISOLD SHSN ARE ANTICIPATED WITH THIS SYSTEM DURING THE MRNG.
TEMPS WERE FORECAST ABOUT 5 DEGREES UNDR THE AVERAGES USING
TWEAKED NAM GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
A GENERALLY DRY AND BELOW NORMAL PERIOD WILL PERSIST ACROSS THE
AREA HEADING INTO THE WEEKEND. DECENT MODEL AGREEMENT EXISTS ON AT
LEAST SOME CLEARING WITH LITTLE CHANCE OF PRECIPITATION UNTIL
SATURDAY NIGHT/SUNDAY. AT THAT TIME...THE MODELS TRACK A DUET OF
SHRTWVS ACRS THE AREA. DUE TO THEIR CONTINENTAL ORIGINS...NEITHER
OF THESE LOOK TO BE PARTICULARLY MOISTURE-LADEN...SO POPS WERE
KEPT TO THE CHANCE CATEGORY FOR THE MOMENT. HOWEVER THROUGHOUT THE
PERIOD...THERMAL PROFILES FROM THE CONSENSUS FAVOR DEEP ENOUGH
COLD AIR TO SUPPORT SNOW THROUGHOUT THEIR PASSAGE.
WHILE TEMPERATURES REMAIN BELOW NORMAL...THEY DO MODERATE FAIRLY
SIGNIFICANTLY TOWARD THE MID 30S BY THE END OF THE WEEKEND.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
BLEND OF RECENT MEDIUM RANGE MODELS SHOW LINGERING POST SYSTEM
CLOUDS ACROSS THE UPPER OHIO VALLEY INTO MONDAY. ENSUING HIGH
PRESSURE WILL PROMOTE A DRY PERIOD INTO MID WEEK.
JUDGING FROM RECENT GFS AND ECMWF MOS...EXPECT TEMPERATURES TO BE
NEAR SEASONABLE LEVELS.
&&
.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
STRATOCU CLOUD DECK WILL PROVIDE MVFR RESTRICTIONS AT ALL PORTS
THROUGH AT LEAST DAWN. WAA WILL BEGIN IN ERNEST AFTER DAWN...ERODING
THE CLOUD FROM WEST TO EAST DURING THE MORNING HOURS. THIS WILL
RETURN MOST PORTS TO VFR. AS PER USUAL...THE COLD AIR WILL GET HUNG
UP ACROSS THE NORTH...KEEPING FKL AND DUJ IN MVFR.
NAM MODEL PROFILES SHOW VERTICAL MIXING WILL CAUSE SURFACE
WINDS...FROM THE SOUTHWEST THIS AFTERNOON...TO INCREASE TO 10 KTS
WITH GUSTS TO ABOUT 20 KTS. WINDS CAN BE A TAD MORE WESTERLY TONIGHT
AND LESS GUSTY. WINDS FRIDAY CAN AGAIN BE SOUTHWEST AT 10 KTS WITH
GUSTS TO 20 KTS.
.OUTLOOK.../SATURDAY THROUGH TUESDAY/...
VFR UNTIL POSSIBLE RESTRICTIONS SATURDAY NIGHT AND SUNDAY AS A
WEAK COLD FRONT MOVES ACROSS THE GREAT LAKES.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
15/22
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
107 AM EST FRI JAN 4 2013
.SYNOPSIS...
A DISTURBANCE MOVING OFF THE GREAT LAKES MAY SPAWN SCATTERED
LIGHT SNOW SHOWERS TONIGHT. OTHERWISE...SEASONABLY COLD WEATHER
WILL CONTINUE INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
STRATOCU BLANKET PERSISTS OVR THE UPR OH REGION THIS MRNG AS
SHRTWV...BEST EXHIBITED VIA MID LVL THERMAL TROF IN RAP MDL AND BY
IR SATELLITE PICS...CONTS EWD PROGRESS. NO MORE THAN FLURRIES OR
AN ISOLD SHSN ARE ANTICIPATED WITH THIS SYSTEM DURING THE MRNG.
TEMPS WERE FORECAST ABOUT 5 DEGREES UNDR THE AVERAGES USING
TWEAKED NAM GUIDANCE.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY/...
A GENERALLY DRY AND BELOW NORMAL PERIOD WILL PERSIST ACROSS THE
AREA HEADING INTO THE WEEKEND. DECENT MODEL AGREEMENT EXISTS ON AT
LEAST SOME CLEARING WITH LITTLE CHANCE OF PRECIPITATION UNTIL
ROUGHLY SATURDAY NIGHT/SUNDAY. AT THAT TIME...THE MODELS TRACK A
DUET OF WAVES NEAR THE AREA...FIRST FROM THE SOUTHERN
STREAM...THEN A MORE CLIPPERESQUE TYPE MID-LEVEL SYSTEM THAT DROPS
SOUTHEASTWARD FROM THE CANADIAN PRAIRIE PROVINCES. DUE TO THEIR
CONTINENTAL ORIGINS...NEITHER OF THESE LOOK TO BE PARTICULARLY
MOISTURE-LADEN...SO POPS WERE KEPT TO THE CHANCE CATEGORY FOR THE
MOMENT. HOWEVER THROUGHOUT THE PERIOD...THERMAL PROFILES FROM THE
CONSENSUS FAVOR DEEP ENOUGH COLD AIR TO SUPPORT SNOW THROUGHOUT
THEIR PASSAGE.
WHILE TEMPERATURES REMAIN BELOW NORMAL...THEY DO MODERATE FAIRLY
SIGNIFICANTLY TOWARD THE MID 30S BY THE END OF THE WEEKEND. THIS
WILL BE A BRIEF SEGUE TO MUCH MORE ABRUPT WARMING BY NEXT WEEK.
FRIES
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
BLEND OF RECENT MEDIUM RANGE MODELS SHOW LINGERING POST SYSTEM
CLOUDS ACROSS THE UPPER OHIO VALLEY INTO MONDAY. ENSUING HIGH
PRESSURE WILL PROMOTE A DRY PERIOD INTO MID WEEK.
JUDGING FROM RECENT GFS AND ECMWF MOS...EXPECT TEMPERATURES TO BE
NEAR SEASONABLE LEVELS.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
STRATOCU CLOUD DECK WILL PROVIDE MVFR RESTRICTIONS AT ALL PORTS
THROUGH AT LEAST DAWN. WAA WILL BEGIN IN ERNEST AFTER DAWN...ERODING
THE CLOUD FROM WEST TO EAST DURING THE MORNING HOURS. THIS WILL
RETURN MOST PORTS TO VFR. AS PER USUAL...THE COLD AIR WILL GET HUNG
UP ACROSS THE NORTH...KEEPING FKL AND DUJ IN MVFR.
NAM MODEL PROFILES SHOW VERTICAL MIXING WILL CAUSE SURFACE
WINDS...FROM THE SOUTHWEST THIS AFTERNOON...TO INCREASE TO 10 KTS
WITH GUSTS TO ABOUT 20 KTS. WINDS CAN BE A TAD MORE WESTERLY TONIGHT
AND LESS GUSTY. WINDS FRIDAY CAN AGAIN BE SOUTHWEST AT 10 KTS WITH
GUSTS TO 20 KTS.
.OUTLOOK.../SATURDAY THROUGH TUESDAY/...
VFR UNTIL POSSIBLE RESTRICTIONS SATURDAY NIGHT AND SUNDAY AS A
WEAK COLD FRONT MOVES ACROSS THE GREAT LAKES.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
15/22
AREA FORECAST DISCUSSION
NWS DULUTH MN
723 PM CST SAT JAN 5 2013
.UPDATE...
LOW PRESSURE IN UPPER MICHIGAN CONTINUE TO MOVE EAST THIS
EVENING...WITH WINDS BECOMING NORTH OVER LAKE SUPERIOR...AND LOWER
CLOUDS MOVING OVER NORTHERN WISCONSIN AS WELL. MORE CLOUDS OVER
THE RED RIVER VALLEY WERE MOVING E-SE THIS EVENING...AND THE RAP
900-925MB CONDENSATION PRESSURE DEFICITS WERE HANDLING THIS PRETTY
WELL...AND IT BRINGS THESE CLOUDS TO OUR WESTERN BORDER LATE
TONIGHT. WE`LL HAVE TO KEEP AN EYE ON THESE AND INCREASE CLOUD
COVER IF THEY HAPPEN TO MOVE IN FASTER.
WE DON`T PLAN ON ANY MAJOR CHANGES TO THE GRIDS OVERNIGHT...WE
STILL EXPECT LAKE EFFECT SNOW SHOWERS TO DEVELOP IN THE
SNOWBELT...MAINLY IN IRON/ASHLAND COUNTIES. WE DID INCREASE
SNOWFALL A BIT OVER IRON COUNTY AS INVERSION LEVELS INCREASE
TONIGHT WITH DELTA-T`S FORECAST TO ABOUT 15-17C.
&&
.PREV DISCUSSION... /ISSUED 535 PM CST SAT JAN 5 2013/
AVIATION...00Z TAFS
IFR/LOW MVFR CEILINGS COVERED MUCH OF NORTHEAST MINNESOTA...AND
THEY WERE WORKING THEIR WAY SOUTH INTO NORTHWEST WISCONSIN AS
WELL. MORE LOW CEILINGS WERE OVER PORTIONS OF EASTERN NORTH
DAKOTA. WE EXPECT THOSE CEILINGS WILL WORK EAST THROUGH THE
NIGHT...BUT THE RAP WHICH IS HANDLING THEM PRETTY WELL...KEEPS
THEM WEST OF KINL/KBRD THROUGH 14Z. A SURFACE LOW OVER WESTERN
UPPER MICHIGAN WILL CONTINUE TO MOVE OFF TONIGHT...DRAWING THOSE
LOWER CEILINGS SOUTH AND EAST. WE KEPT THE MENTION OF THESE CLOUDS IN
THE KDLH/KHIB TAFS THROUGH ABOUT 7-8Z...AND UNTIL 15Z AT KHYR.
MOST AREAS WILL BE VFR ON SUNDAY...OUTSIDE OF SOME LAKE CLOUDS
ALONG THE SOUTH SHORE.
PREV DISCUSSION... /ISSUED 251 PM CST SAT JAN 5 2013/
SHORT TERM...
THIS AFTERNOON/TONIGHT THROUGH SUNDAY NIGHT...
MAIN CONCERNS IN THE SHORT TERM ARE FOCUSED AROUND THE CHANCE OF
LIGHT SNOW EXPECTED TO DEVELOP THIS EVENING ACROSS NE MN AND
LINGER THROUGH NW WI INTO SUNDAY MORNING...ALONG WITH TEMPERATURES
THROUGH THE NEAR TERM.
ATMOSPHERE REMAINS FAIRLY DRY ACROSS THE REGION WITH A SHARP UPPER
TROUGH OVER THE RED RIVER VALLEY MOVING EWD INTO NRN MN THIS
AFTERNOON. BENIGN SFC LOW CURRENTLY POSITIONED NEAR LAKE MILLE
LACS WITH LITTLE IN THE WAY OF CLOUD COVER ASSOCIATED WITH IT
ATTM. LOW LEVEL FLOW PATTERN WITH EAST WINDS OFF LAKE SUPERIOR
INTO THE ARROWHEAD HAVE ALLOWED LOW CLOUDS TO PERSIST OVER THE NRN
THIRD OF THE FORECAST AREA TODAY. THIS AREA OF LOW CLOUDS WILL
COMBINE WITH THE INCOMING S/W AND INCREASE IN AREAL COVERAGE
BEFORE DEVELOPING LIGHT SNOW/FLURRIES ALONG AND EAST OF HIGHWAY 53
EARLY THIS EVENING. ONLY LIGHT OR TRACE ACCUMULATIONS ARE EXPECTED
OVER NE MN TONIGHT.
BY LATE THIS EVENING...THE BL FLOW ACROSS WRN LAKE SUPERIOR WILL
BECOME MORE NRLY AS THE SFC LOW SLIDES FURTHER TO THE EAST. THE
COMBINATION OF 15 TO 25 KT NORTH WINDS OFF THE LAKE WITH A LONG
FETCH OVER WATER...A RELATIVELY DEEP BL ROUGHLY 3-4K FT...AND
COLD ENOUGH TEMPS ALOFT TO PRODUCE MODEST LOW LVL
INSTABILITY...THE POTENTIAL FOR LIGHT LAKE EFFECT SNOW ALONG THE
SOUTH SHORE ARISES. LAKE TEMPS ARE AROUND +2.7 DEG C AND 850MB
TEMPS WILL BE -11 TO -12 DEG C. KEPT WITH PREVIOUS FORECAST OF
LIKELY POPS FROM NRN BAYFIELD TO NRN ASHLAND/IRON COUNTIES FROM
06-12Z LATE TONIGHT/EARLY SUN MORNING...AND GENERALLY 1-2 INCHES
OF SNOW IN THIS AREA.
HIGH PRESSURE QUICKLY BUILDS IN SUNDAY AFTERNOON AND ALLOWS
CONDITIONS TO DRY OUT. SHOULD SEE MOSTLY SUNNY TO PARTLY CLOUDY
SKIES FOR THE END OF THE WEEKEND.
LOW TEMPERATURES TONIGHT WILL BE SOMEWHAT TRICKY AS CLOUD COVER
COULD END UP BEING PATCHY IN NATURE OVER PARTS OF NE MN. WILL
LIKELY SEE SINGLE DIGITS ABOVE AND BELOW ZERO ACROSS NRN MN...WITH
A FEW TEENS BELOW ZERO NOT OUT OF THE QUESTION WHERE ADDITIONAL
CLEARING OCCURS. AREAS TO THE EAST IN NW WI WILL BE SLIGHTLY
WARMER WITH ADDITIONAL CLOUD COVER ALMOST CERTAIN. SHOULD SEE
LOWER TO MID TEENS IN THIS AREA. ON SUNDAY...A LINGERING COLD AIR
MASS WILL ONLY ALLOW TEMPS TO REACH INTO THE UPPER TEENS TO MID
20S...EVEN WITH MOSTLY SUNNY SKIES IN THE AFTERNOON. LOWS SUNDAY
NIGHT WILL DROP INTO THE UPPER SINGLE DIGITS AND TEENS ABOVE
ZERO...WITH HIGH CLOUDS MOVING IN FROM THE NW.
LONG TERM...
MONDAY THROUGH SATURDAY...
AN UNSEASONABLY MILD PATTERN WILL CONTINUE THROUGHOUT THE
EXTENDED TIME PERIOD ACROSS THE NORTHLAND. IT ALSO LOOKS FAIRLY
QUIET FOR THE MOST PART. LOW PRESSURE MOVING ACROSS THE CENTRAL
CANADIAN PROVINCES WILL AFFECT AREAS MAINLY NORTH OF THE BORDER ON
MONDAY AND MONDAY NIGHT...WITH A FAIR AMOUNT OF SUNSHINE FURTHER
SOUTH. THE MODELS DIVERGE QUITE A BIT IN HOW THEY HANDLE A SYSTEM
ON TUESDAY AND WEDNESDAY. THE ECMWF AND GEM ARE FAIRLY SIMILAR BUT
THE GFS SHOWS A LOW PRESSURE SYSTEM DEVELOPING IN CENTRAL NORTH
DAKOTA BY 00Z WEDNESDAY. THE RESULT COULD BE SOME SCATTERED SNOW
SHOWERS TUESDAY NIGHT AND WEDNESDAY AS THE SYSTEM MOVES THROUGH.
HIGH PRESSURE WILL GENERALLY CONTROL LATER WEDNESDAY AND WEDNESDAY
NIGHT. THURSDAY LOOKS QUITE MILD WITH TEMPS WELL INTO THE 30S
AHEAD OF LOW PRESSURE DEVELOPING IN THE NORTHERN ROCKIES. THERE
ARE SOME HUGE MODEL DIFFERENCES BEGINNING ON FRIDAY AND CONTINUING
INTO THE WEEKEND SO KEEPING POPS LOW FOR NOW. THE GFS CONTINUES TO
TRY TO DEVELOP A MAJOR LOW BY NEXT WEEKEND...WHICH WOULD IMPACT
OUR AREA. THE ECMWF IS MUCH FURTHER SE AND NOT NECESSARILY OF MUCH
CONCERN FOR OUR CWA. DEFINITELY SOMETHING TO KEEP AN EYE ON...AS
THE GFS HAS BEEN REASONABLY CONSISTENT.
&&
.POINT TEMPS/POPS...
DLH 8 20 10 30 / 20 0 0 10
INL -1 17 12 28 / 10 0 0 10
BRD 4 21 12 31 / 10 0 0 10
HYR 12 22 9 33 / 30 10 0 10
ASX 18 24 13 34 / 50 20 0 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 10 AM CST SUNDAY FOR LSZ121-146>148.
&&
$$
SHORT TERM...MELDE
LONG TERM....DAP
AREA FORECAST DISCUSSION
NWS DULUTH MN
535 PM CST SAT JAN 5 2013
.AVIATION...00Z TAFS
IFR/LOW MVFR CEILINGS COVERED MUCH OF NORTHEAST MINNESOTA...AND
THEY WERE WORKING THEIR WAY SOUTH INTO NORTHWEST WISCONSIN AS
WELL. MORE LOW CEILINGS WERE OVER PORTIONS OF EASTERN NORTH
DAKOTA. WE EXPECT THOSE CEILINGS WILL WORK EAST THROUGH THE
NIGHT...BUT THE RAP WHICH IS HANDLING THEM PRETTY WELL...KEEPS
THEM WEST OF KINL/KBRD THROUGH 14Z. A SURFACE LOW OVER WESTERN
UPPER MICHIGAN WILL CONTINUE TO MOVE OFF TONIGHT...DRAWING THOSE
LOWER CEILINGS SOUTH AND EAST. WE KEPT THE MENTION OF THESE CLOUDS IN
THE KDLH/KHIB TAFS THROUGH ABOUT 7-8Z...AND UNTIL 15Z AT KHYR.
MOST AREAS WILL BE VFR ON SUNDAY...OUTSIDE OF SOME LAKE CLOUDS
ALONG THE SOUTH SHORE.
&&
.PREV DISCUSSION... /ISSUED 251 PM CST SAT JAN 5 2013/
SHORT TERM...
THIS AFTERNOON/TONIGHT THROUGH SUNDAY NIGHT...
MAIN CONCERNS IN THE SHORT TERM ARE FOCUSED AROUND THE CHANCE OF
LIGHT SNOW EXPECTED TO DEVELOP THIS EVENING ACROSS NE MN AND
LINGER THROUGH NW WI INTO SUNDAY MORNING...ALONG WITH TEMPERATURES
THROUGH THE NEAR TERM.
ATMOSPHERE REMAINS FAIRLY DRY ACROSS THE REGION WITH A SHARP UPPER
TROUGH OVER THE RED RIVER VALLEY MOVING EWD INTO NRN MN THIS
AFTERNOON. BENIGN SFC LOW CURRENTLY POSITIONED NEAR LAKE MILLE
LACS WITH LITTLE IN THE WAY OF CLOUD COVER ASSOCIATED WITH IT
ATTM. LOW LEVEL FLOW PATTERN WITH EAST WINDS OFF LAKE SUPERIOR
INTO THE ARROWHEAD HAVE ALLOWED LOW CLOUDS TO PERSIST OVER THE NRN
THIRD OF THE FORECAST AREA TODAY. THIS AREA OF LOW CLOUDS WILL
COMBINE WITH THE INCOMING S/W AND INCREASE IN AREAL COVERAGE
BEFORE DEVELOPING LIGHT SNOW/FLURRIES ALONG AND EAST OF HIGHWAY 53
EARLY THIS EVENING. ONLY LIGHT OR TRACE ACCUMULATIONS ARE EXPECTED
OVER NE MN TONIGHT.
BY LATE THIS EVENING...THE BL FLOW ACROSS WRN LAKE SUPERIOR WILL
BECOME MORE NRLY AS THE SFC LOW SLIDES FURTHER TO THE EAST. THE
COMBINATION OF 15 TO 25 KT NORTH WINDS OFF THE LAKE WITH A LONG
FETCH OVER WATER...A RELATIVELY DEEP BL ROUGHLY 3-4K FT...AND
COLD ENOUGH TEMPS ALOFT TO PRODUCE MODEST LOW LVL
INSTABILITY...THE POTENTIAL FOR LIGHT LAKE EFFECT SNOW ALONG THE
SOUTH SHORE ARISES. LAKE TEMPS ARE AROUND +2.7 DEG C AND 850MB
TEMPS WILL BE -11 TO -12 DEG C. KEPT WITH PREVIOUS FORECAST OF
LIKELY POPS FROM NRN BAYFIELD TO NRN ASHLAND/IRON COUNTIES FROM
06-12Z LATE TONIGHT/EARLY SUN MORNING...AND GENERALLY 1-2 INCHES
OF SNOW IN THIS AREA.
HIGH PRESSURE QUICKLY BUILDS IN SUNDAY AFTERNOON AND ALLOWS
CONDITIONS TO DRY OUT. SHOULD SEE MOSTLY SUNNY TO PARTLY CLOUDY
SKIES FOR THE END OF THE WEEKEND.
LOW TEMPERATURES TONIGHT WILL BE SOMEWHAT TRICKY AS CLOUD COVER
COULD END UP BEING PATCHY IN NATURE OVER PARTS OF NE MN. WILL
LIKELY SEE SINGLE DIGITS ABOVE AND BELOW ZERO ACROSS NRN MN...WITH
A FEW TEENS BELOW ZERO NOT OUT OF THE QUESTION WHERE ADDITIONAL
CLEARING OCCURS. AREAS TO THE EAST IN NW WI WILL BE SLIGHTLY
WARMER WITH ADDITIONAL CLOUD COVER ALMOST CERTAIN. SHOULD SEE
LOWER TO MID TEENS IN THIS AREA. ON SUNDAY...A LINGERING COLD AIR
MASS WILL ONLY ALLOW TEMPS TO REACH INTO THE UPPER TEENS TO MID
20S...EVEN WITH MOSTLY SUNNY SKIES IN THE AFTERNOON. LOWS SUNDAY
NIGHT WILL DROP INTO THE UPPER SINGLE DIGITS AND TEENS ABOVE
ZERO...WITH HIGH CLOUDS MOVING IN FROM THE NW.
LONG TERM...
MONDAY THROUGH SATURDAY...
AN UNSEASONABLY MILD PATTERN WILL CONTINUE THROUGHOUT THE
EXTENDED TIME PERIOD ACROSS THE NORTHLAND. IT ALSO LOOKS FAIRLY
QUIET FOR THE MOST PART. LOW PRESSURE MOVING ACROSS THE CENTRAL
CANADIAN PROVINCES WILL AFFECT AREAS MAINLY NORTH OF THE BORDER ON
MONDAY AND MONDAY NIGHT...WITH A FAIR AMOUNT OF SUNSHINE FURTHER
SOUTH. THE MODELS DIVERGE QUITE A BIT IN HOW THEY HANDLE A SYSTEM
ON TUESDAY AND WEDNESDAY. THE ECMWF AND GEM ARE FAIRLY SIMILAR BUT
THE GFS SHOWS A LOW PRESSURE SYSTEM DEVELOPING IN CENTRAL NORTH
DAKOTA BY 00Z WEDNESDAY. THE RESULT COULD BE SOME SCATTERED SNOW
SHOWERS TUESDAY NIGHT AND WEDNESDAY AS THE SYSTEM MOVES THROUGH.
HIGH PRESSURE WILL GENERALLY CONTROL LATER WEDNESDAY AND WEDNESDAY
NIGHT. THURSDAY LOOKS QUITE MILD WITH TEMPS WELL INTO THE 30S
AHEAD OF LOW PRESSURE DEVELOPING IN THE NORTHERN ROCKIES. THERE
ARE SOME HUGE MODEL DIFFERENCES BEGINNING ON FRIDAY AND CONTINUING
INTO THE WEEKEND SO KEEPING POPS LOW FOR NOW. THE GFS CONTINUES TO
TRY TO DEVELOP A MAJOR LOW BY NEXT WEEKEND...WHICH WOULD IMPACT
OUR AREA. THE ECMWF IS MUCH FURTHER SE AND NOT NECESSARILY OF MUCH
CONCERN FOR OUR CWA. DEFINITELY SOMETHING TO KEEP AN EYE ON...AS
THE GFS HAS BEEN REASONABLY CONSISTENT.
&&
.POINT TEMPS/POPS...
DLH 8 20 10 30 / 20 0 0 10
INL -1 17 12 28 / 10 0 0 10
BRD 4 21 12 31 / 10 0 0 10
HYR 12 22 9 33 / 30 10 0 10
ASX 18 24 13 34 / 50 20 0 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 10 AM CST SUNDAY
FOR LSZ121-146>148.
&&
$$
SHORT TERM...TENTINGER
LONG TERM....DAP
AVIATION.....MELDE
AREA FORECAST DISCUSSION
NWS BUFFALO NY
347 PM EST FRI JAN 4 2013
.SYNOPSIS...
WINDS WILL DIMINISH TONIGHT AS LOW PRESSURE LIFTS INTO QUEBEC AND
THEN FINALLY AWAY FROM THE REGION. HIGH PRESSURE WILL BRING A DRY
SATURDAY...BEFORE AN AREA OF LOW PRESSURE MOVES THROUGH THE GREAT
LAKES SATURDAY NIGHT AND SUNDAY WITH A WIDESPREAD LIGHT SNOWFALL.
&&
.NEAR TERM /THROUGH SATURDAY/...
WINDS LOOK TO HAVE PEAKED ACROSS THE AREA EARLIER THIS AFTERNOON
WITH ONLY A FEW LOCATIONS DOWNWIND OF THE LAKES CONTINUING TO SEE
ADVISORY LEVEL WIND GUSTS. EXPECT WINDS TO BE ENOUGH BELOW THRESHOLD
LEVELS TO DROP THE ADVISORY FOR MUCH OF THE AREA...ONLY HOLDING ONTO
TO IT FOR AREAS NORTHEAST OF THE LAKES. THE STRONG WINDS WILL
CONTINUE TO CAUSE BLOWING AND DRIFTING PROBLEMS INTO THIS EVENING.
THE LOW LEVEL WIND MAXIMUM WILL SHIFT EAST THIS EVENING...COMBINED
WITH A RELAXING OF THE PRESSURE GRADIENT WILL BRING WINDS BELOW
ADVISORY LEVEL DOWNWIND OF THE LAKES BEFORE MIDNIGHT.
AN UPTICK TO SNOW SHOWER ACTIVITY IS EXPECTED TONIGHT EAST OF LAKE
ONTARIO AS A NORTHERN STREAM SHORTWAVE AND ITS ATTENDANT WEAK COLD
FRONT PUSH SOUTHWARD ACROSS THE REGION. THE MEAN WEST TO
SOUTHWESTERLY FLOW AHEAD OF THIS FEATURE WILL BRING SOME OPPORTUNITY
FOR LAKE ENHANCEMENT. HOWEVER...DRIER AIR ADVECTING INTO THE REGION
SHOULD LIMIT ACCUMULATION POTENTIAL AND WE SHOULD ONLY SEE MINOR
ACCUMULATIONS AT BEST. LOCAL WRF RUNS AND HRRR SUGGESTING THE
POSSIBILITY THAT A SNOW NARROW BAND COULD FORM FARTHER TO THE
WEST...BUT THIS POTENTIAL LOOKS LIMITED BASED ON THE AMOUNT OF DRY
AIR ADVECTING INTO THE AREA...WITH AT LEAST PARTIAL CLEARING TAKING
PLACE ACROSS A GOOD PORTION OF THE AREA.
QUIETER WEATHER LOOKS IN STORE FOR SATURDAY AS THE SURFACE HIGH
RIDGES ACROSS THE AREA. ANY MORNING SUNSHINE WILL GIVE WAY TO
INCREASING CLOUD COVER DURING THE AFTERNOON AHEAD OF THE VIGOROUS
SHORTWAVE APPROACHING FROM THE PLAINS.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
SATURDAY NIGHT THROUGH SUNDAY NIGHT...A SERIES OF SHORT WAVES WILL
BE ROUNDING THE BASE OF THE PERSISTENT UPPER LEVEL TROUGH THAT HAS
BEEN IN PLACE OVER SOUTHEAST CANADA AND THE GREAT LAKES. THE LIFT
ASSOCIATED WITH THESE IMPULSES WILL KEEP UNSETTLED WEATHER OVER OUR
AREA UNTIL THE UPPER LEVEL TROUGH LIFTS OUT ACROSS NEW ENGLAND LATER
SUNDAY NIGHT AND MONDAY.
THE FIRST SIGNIFICANT SHORT WAVE IS HEADING SOUTHEAST TOWARD THE
NORTHERN ROCKIES THIS FRIDAY AFTERNOON. THE SURFACE LOW THAT IS
ASSOCIATED WITH THIS SHORT WAVE WILL REACH THE CENTRAL GREAT LAKES
SATURDAY NIGHT BEFORE TRACKING EAST ACROSS LAKE ONTARIO AND NORTHERN
NEW YORK STATE ON SUNDAY. WARM AIR ADVECTION AHEAD OF THE
LOW...COMBINED WITH THE LIFT ASSOCIATED WITH A LEAD SHORT WAVE...
WILL CAUSE LIGHT SNOW TO SPREAD EAST ACROSS THE AREA SATURDAY NIGHT.
EXPECT GENERAL ACCUMULATIONS OF AN INCH OR LESS...WITH SLIGHTLY
HIGHER AMOUNTS POSSIBLE ACROSS THE NORTH COUNTRY AND ST LAWRENCE
RIVER VALLEY WHERE THERE WILL BE ADDITIONAL LIFT IN THE VICINITY OF
A PASSING WARM FRONT.
THERE MAY BE A LULL IN THE GENERAL SNOWFALL SUNDAY MORNING BEFORE
MOISTURE INCREASES AGAIN DURING THE AFTERNOON AS THE SURFACE LOW
PUSHES EAST ACROSS LAKE ONTARIO. ADDITIONAL ACCUMULATIONS OF AN INCH
OR LESS ARE EXPECTED...WITH ANOTHER 1 TO 3 INCHES POSSIBLE EAST OF
LAKE ONTARIO DUE TO CONVERGENCE ALONG THE FRONT THAT WILL BE
EXTENDING EAST OF THE SURFACE LOW.
THE SNOW WILL TAPER OFF FROM WEST TO EAST SUNDAY NIGHT AS THE UPPER
LEVEL TROUGH AND ASSOCIATED SURFACE LOW SLIDE OFF THE NEW ENGLAND
COAST. THE NAM SHOWS MUCH DRIER AIR BUILDING IN BEHIND THE LOW
DURING THE SECOND HALF OF SUNDAY NIGHT...WHILE THE GFS HOLDS THE LOW
LEVEL MOISTURE IN A LITTLE LONGER. IF ENOUGH LOW LEVEL MOISTURE
REMAINS IN PLACE WITH THE NORTHERLY UPSLOPE FLOW BEHIND THE
DEPARTING LOW...SOME LIGHT SNOW OR FREEZING DRIZZLE COULD LINGER
THROUGH THE NIGHT.
HIGH PRESSURE AND DRIER AIR WILL BUILD ACROSS NEW YORK STATE ON
MONDAY AND BRING MOSTLY SUNNY SKIES TO THE AREA. EXPECT MAINLY CLEAR
SKIES MONDAY NIGHT AS THE SURFACE HIGH SLIDES OFF THE NEW ENGLAND
COAST.
A PERSISTENT SOUTHWEST FLOW AHEAD OF THE SURFACE LOW WILL ALLOW
TEMPERATURES TO HOLD STEADY IN THE 20S SATURDAY NIGHT...WITH UPPER
TEENS POSSIBLE EAST OF LAKE ONTARIO. MOST AREAS WILL SEE
TEMPERATURES MODERATING IN THE MID OR UPPER 30S SUNDAY...BEFORE THE
NORTHERLY FLOW BEHIND THE SURFACE LOW CAUSES TEMPERATURES TO FALL
BACK INTO THE UPPER TEENS/LOWER 20S SUNDAY NIGHT. READINGS MAY DIP
INTO THE SINGLE DIGITS EAST OF LAKE ONTARIO. TEMPERATURES WILL
STRUGGLE TO GET OUT OF THE 20S ON MONDAY IN SPITE OF THE ANTICIPATED
SUNSHINE.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
A GENERAL ZONAL FLOW IS FORECAST TO BE IN PLACE ALONG THE
CANADIAN/US BORDER TUESDAY AND WEDNESDAY...WHILE A CLOSED LOW LIFTS
OUT OF THE SOUTHWEST PART OF THE COUNTRY. THE GFS AND ECMWF STILL
HAVE SIGNIFICANT DISCREPANCIES IN THE WAY THEY HANDLE THIS CUTOFF
LOW. THE ECWMF KEEPS THE LOW OVER THE SOUTHERN PLAINS THROUGH
WEDNESDAY...BEFORE LIFTING IT OUT INTO THE MIDWEST ON
THURSDAY...WHILE THE GFS LIFTS THE LOW OUT ON WEDNESDAY AND TRACKS
AN OPEN WAVE TOWARD THE LOWER LAKE ON THURSDAY. FOR NOW...WILL
CONTINUE TO HPC GUIDANCE WHICH SEEMS TO FAVOR THE MORE CONSERVATIVE
ECMWF SOLUTION. BASED ON THIS GUIDANCE...WILL KEEP THE AREA DRY
THROUGH WEDNESDAY NIGHT AS THE SURFACE LOW THAT WILL BE ASSOCIATED
WITH THE CLOSED STAYS WELL TO OUR WEST.
THE ECMWF LIFTS THE CLOSED LOW INTO THE MIDWEST ON THURSDAY...THEN
OPEN THE WAVE UP ON FRIDAY AS IT TRACKS IT EAST ACROSS THE LOWER
LAKES. THE CORRESPONDING SURFACE LOW IS FORECAST TO HEAD NORTHEAST
TOWARD THE CENTRAL GREAT LAKES ON THURSDAY...BEFORE TRACKING NORTH
OF LAKE ONTARIO ON FRIDAY. THE DEEP LAYERED SOUTHERLY FLOW AHEAD OF
THIS SYSTEM WILL TRANSPORT MILDER AIR NORTH TOWARD OUR AREA. WHILE
TEMPERATURES ALOFT LOOK WARM ENOUGH TO SUPPORT MAINLY RAIN...SURFACE
TEMPERATURES WILL BE THE KEY TO THE PCPN TYPE. BASED ON FORECAST
TEMPERATURES...WE MAY SEE A MIX OF FROZEN PCPN THURSDAY MORNING
BEFORE TEMPERATURES WARM UP ENOUGH FOR A POSSIBLE CHANGEOVER TO ALL
RAIN DURING THE AFTERNOON. MIXED PCPN COULD SET UP AGAIN ACROSS THE
HIGHER ELEVATIONS THURSDAY NIGHT BEFORE ALL PCPN CHANGES BACK OVER
TO RAIN ON FRIDAY. STAY TUNED TO LATER MODEL RUNS WHICH WILL HELP TO
FINE TUNE THIS POTENTIAL FOR MIXED PCPN.
REGARDING TEMPERATURES...EXPECT A MODERATING TREND THAT WILL SEE
DAYTIME HIGHS RISING INTO THE UPPER 30S/LOWER 40S ON WEDNESDAY AND
THURSDAY...AND MAYBE EVEN THE MID 40S ON FRIDAY.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
BIGGEST AVIATION IMPACT INTO THIS EVENING WILL BE THE STRONG
SOUTHWEST WINDS. KIAG/KBUF/KROC/KART WILL ALL EXPERIENCE WINDS
GUSTS TO AT LEAST 40 KNOTS WITH PERIODIC GUSTS CLOSE TO 50
KNOTS...ESPECIALLY AT KIAG AND KBUF. ALTHOUGH SNOW IS NOT
FALLING...THE STRONG WINDS ARE CREATING BLOWING SNOW WITH VSBY
RESTRICTIONS. THE VSBY RESTRICTIONS WILL BE HIGHLY VARIABLE...BUT
COULD BRIEFLY DROP TO IFR WITH THE HIGHEST WIND GUSTS.
WINDS WILL GRADUALLY DIMINISH THIS EVENING AND OVERNIGHT. DRIER AIR
WILL WORK INTO THE REGION FROM THE WEST TONIGHT WITH SKIES BECOMING
AT LEAST PARTLY CLOUDY. THERE IS A CHANCE FOR A BAND OF LAKE
EFFECT SNOW TO DEVELOP EAST AND SOUTHEAST OF LAKE ONTARIO
TONIGHT...BUT WITH THE DRIER AIR ADVECTING INTO THE REGION
IMPACTS WILL BE MINIMAL.
OUTLOOK...
SATURDAY...MAINLY VFR.
SUNDAY...MVFR/IFR WITH CHANCE OF SNOW SHOWERS.
MONDAY AND TUESDAY...VFR.
WEDNESDAY...VFR/MVFR WITH A CHANCE OF RAIN.
&&
.MARINE...
WINDS GUSTS HAVE LIKELY PEAKED OVER THE LOWER LAKES...BUT GALES WILL
CONTINUE INTO THIS EVENING. ONCE WINDS HAVE LOWERED BELOW GALE FORCE
SMALL CRAFT CONDITIONS WILL LINGER INTO SATURDAY...BEFORE BRIEFLY
DYING OFF FROM MID DAY SATURDAY INTO SATURDAY NIGHT. WINDS WILL
AGAIN RAMP UP FROM THE SOUTHWEST LATE SATURDAY NIGHT AND SUNDAY
AHEAD OF A DEVELOPING LOW WITH SOME SMALL CRAFT CONDITIONS POSSIBLE
DURING THIS TIME FRAME.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR NYZ001>003-007-
010-011.
MARINE...GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LEZ020-040-041.
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LOZ030-
043>045-063>065.
&&
$$
SYNOPSIS...TMA
NEAR TERM...TMA
SHORT TERM...TJP
LONG TERM...TJP
AVIATION...TMA
MARINE...TMA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
953 PM CST SAT JAN 5 2013
.DISCUSSION...
DELAYED CLOUD COVER A BIT IN THE NORTH AS SATELLITE SHOWS CLOUD
DECK STILL IN SOUTHERN CANADA. UPDATED HOURLY TEMP TRENDS FOR SOME
WARMING NORTH DUE TO CLOUD COVER AND SOUTHWEST DUE TO SOUTHERLY
WINDS. LEFT FOG IN FOR THE CENTRAL AND NORTHWEST AS LOW LEVEL
MOISTURE SUGGEST PATCHY FOG IS POSSIBLE.
&&
.AVIATION...
THE LATEST HOURLY RUN OF THE RAP MODEL HAS A GOOD HANDLE ON THE
LOW CLOUDS CURRENTLY IMPACTING THE JAMES RIVER VALLEY AND THE
ADJACENT SOUTHERN CANADIAN PROVINCES. AFTER A PERIOD OF CLEARING
AT KJMS...STRATUS IS EXPECTED TO MOVE BACK IN AROUND 09Z. STRATUS
ALSO EXPECTED AT KMOT AROUND 04Z THIS EVENING. WILL MAINTAIN VFR
CONDITIONS AT KBIS/KISN/KDIK AND MONITOR PROGRESSION OF CLOUD SHIELD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...MM
AVIATION...RK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
735 PM CST SAT JAN 5 2013
.DISCUSSION...
UPDATE FOR MINOR CHANGES TO TEMPS/SKY COVER OVERNIGHT. STRATUS
WILL EXIT THE JAMES RIVER VALLEY THIS EVENING...BUT ANOTHER AREA
OF LOW CLOUDS IN SOUTHERN CANADA IS POISED TO OVERSPREAD NORTH
CENTRAL AND EASTERN PORTIONS OF THE FORECAST AREA OVERNIGHT.
&&
.AVIATION...
THE LATEST HOURLY RUN OF THE RAP MODEL HAS A GOOD HANDLE ON THE
LOW CLOUDS CURRENTLY IMPACTING THE JAMES RIVER VALLEY AND THE
ADJACENT SOUTHERN CANADIAN PROVINCES. AFTER A PERIOD OF CLEARING
AT KJMS...STRATUS IS EXPECTED TO MOVE BACK IN AROUND 09Z. STRATUS
ALSO EXPECTED AT KMOT AROUND 04Z THIS EVENING. WILL MAINTAIN VFR
CONDITIONS AT KBIS/KISN/KDIK AND MONITOR PROGRESSION OF CLOUD SHIELD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...
AVIATION...
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
930 PM CST SAT JAN 5 2013
.DISCUSSION.../ISSUED AT 930 PM CST/
LOW CLOUDS ARE CLEARING VERY STRONGLY. LINGERING BAND OF LOW LEVEL
MOISTURE WEST WAITING FOR WARM ADVECTION TO START LOOKS TOO WEAK
WITH CLOUDS THERE RAPIDLY DISSIPATING...AND GIVEN NEW NAM RH
FIELDS...REDEVELOPMENT NOT EXPECTED. SKIES SHOULD GO CLEAR TO MOSTLY
CLEAR TONIGHT. FOR THIS HAVE ALLOWED TEMPERATURES A LITTLE BETTER
LATE DROP AS WINDS CONTINUE TO DECREASE WITH LOWS 2 TO 4 DEGREES
LOWER THAN BEFORE. WHILE SOME WARM ADVECTION UPSTAIRS WILL START
SOON...SURFACE SHOULD BE IGNORED ON THIS TONIGHT. LOW TEMPS IN THE
SINGLE DIGITS EVERYWHERE AND MAYBE A ZERO HERE AND THERE.
&&
.AVIATION.../FOR THE 00Z TAF ISSUANCE/
MVFR STRATUS CONTINUES TO PROGRESS SOUTHWARD THROUGH THE CWA...
ALONG WITH LARGELY VFR-OCCASIONAL MVFR VISIBILITY IN -SN. MAIN AREA
OF STRATUS EXPECTED TO GRADUALLY CLEAR NORTH TO SOUTH THROUGH THE
NIGHT...WITH MAIN QUESTION BEING WHAT WILL HAPPEN WITH ELONGATED
NORTH-SOUTH BAND OF STRATUS EXTENDING THROUGH THE CENTRAL DAKOTAS AT
THE START OF THE PERIOD. RAP MODEL SEEMS TO HAVE BEST HANDLE ON
EXISTENCE OF THIS BAND...AND IT DEPICTS SOUTHERN END ERODING A BIT
AS THE BAND SWINGS EASTWARD THROUGH NORTHEAST PARTS OF OUR FORECAST
AREA AFTER 06Z. COULD SCRAPE KHON/KFSD WITH LOWER END MVFR TO IFR
CEILINGS 06Z-12Z WINDOW IF SOUTHERN END DOES NOT ERODE AS INDICATED
BUT WILL SIDE WITH DRYING IN THIS LAYER FOR NOW AND KEEP THESE TAFS
VFR AFTER 05Z/07Z RESPECTIVELY AS THE PRIMARY STRATUS AREA SHIFTS TO
THE SOUTH. OCCASIONAL NORTHWESTERLY WIND GUSTS 25-30KTS WILL LINGER
INTO THE EARLY PART OF THE TAF PERIOD...GRADUALLY SUBSIDING THROUGH
THE EVENING...WITH GUSTS EXPECTED TO DIMINISH ENTIRELY AS STRATUS
CLEARS.
&&
.PREV DISCUSSION.../ISSUED AT 342 PM CST/
UPPER WAVE PUSHING ACROSS THE DAKOTAS THIS AFTERNOON...DRIVING COLD
FRONT INTO THE FAR EASTERN PORTIONS OF THE STATE AT MID AFTERNOON.
CLOUDS PUSHING IN WITH STRONG COLD AIR ADVECTION...AND WITH OFF
SURFACE TEMPS FALLING QUICKLY TOWARD THOSE FAVORING ICE NUCLEATION...
HAVE SEEN FLURRIES DROP IN TO PARTS OF EAST CENTRAL SOUTH DAKOTA.
THE CLOUDS AND FLURRIES WILL CONTINUE TO PUSH EAST AND SOUTHEAST
THIS EVENING...BUT IT IS CERTAINLY A CHALLENGE AS TO HOW QUICKLY TO
BRING IN A MORE PERMANENT CLEARING. RAP AND 18Z NAM ARE NOW IN
FAVOR OF HANGING BACK A PERIOD OF LOWER CLOUDS LATER INTO THE NIGHT
NEAR/WEST OF THE JAMES RIVER AND THEN DRIFTING EAST AS FLOW ALOFT
STARTS TO TURN A BIT MORE WESTERLY. THIS ALSO PRESENTS A LARGE
CHALLENGE TO TEMPERATURES...WHICH WILL PROVE ALMOST IMPOSSIBLE TO
GET CLOSE ON AN HOURLY TIME FRAME WITH IN AND OUT CLOUD TRENDS.
EXPECT A BETTER PUSH OF CLEARING THROUGH THE EASTERN CWA BY LATER
EVENING...BUT ENOUGH WIND OR A FEW MORE CLOUDS LIKELY TO KEEP TEMPS
FROM PLUNGING TOO FAR ANYWHERE. GENERALLY LOOKING FOR QUITE A FEW
SINGLE DIGITS...WITH READINGS AROUND 10 WEST AS WARMER AIR SHUNTS
EAST FAIRLY QUICKLY.
SUNDAY AGAIN PRESENTS A SMALL CHALLENGE TO TEMPS...WITH A VERY
WEAK GRADIENT THROUGH MIDDAY OR EVEN EARLY AFTERNOON IN THE FAR
SOUTHEAST. LOWER ELEVATION LOCATIONS COULD EASILY ONCE AGAIN FIND
THEMSELVES MIRED IN CHILLIER AIR...WITH THE INCREASING SOUTHERLY
GRADIENT MAINLY ACROSS SOUTHEAST SOUTH DAKOTA AND INTO SOUTHWEST
MINNESOTA DURING THE AFTERNOON. HIGH CLOUDS PUSHING ACROSS WOULD
ONLY ENHANCE THE POTENTIAL FOR THIS TO OCCUR...SO WAS CAREFUL TO
NOT WARM CONDITIONS IN THE EAST TOO MUCH...AND DID NUDGE SOME
TEMPERATURES DOWN ACROSS PARTS OF NW IA. THE WEST WILL BE OPEN TO
SOME BETTER WARMING...BUT EVEN THERE THE INVERSION WILL PRESENT A
BIT OF A CHALLENGE TO LOWER ELEVATION WARMING. /CHAPMAN
THE PATTERN OF MILD WEATHER WILL CONTINUE THROUGH MUCH OF THE WEEK
AS A MORE ZONAL PATTERN SETS UP FOR THE FIRST HALF OF THE WORK WEEK.
MILDER WEST TO SOUTHWEST FLOW WILL MAKE TEMPERATURES QUITE TRICKY TO
PINPOINT...PARTICULARLY REGARDING OVERNIGHT LOWS. FOR SUNDAY
NIGHT...BREEZY SOUTH TO SOUTHWEST WINDS WILL LIKELY RESULT IN A
NON-DIURNAL TEMPERATURE TREND WITH LOWS EXPECTED IN THE EVENING OR
SHORTLY AFTER MIDNIGHT...THEN SLOWLY RISING LATE. THE QUESTION IS
HOW COOL WE WILL BE ABLE TO FALL OFF IN THE EVENING. OTHERWISE...
HIGH TEMPERATURES FOR TUESDAY AND WEDNESDAY WILL LIKELY BE NEAR OR
JUST ABOVE FREEZING...WITH THE HIGHS IN THE LOW 40S POSSIBLE IN
SOUTH CENTRAL SD WHERE THE GREATEST POTENTIAL MIXING OF THE MILD LOW
LEVEL TEMPERATURES COULD OCCUR.
LATEST MODEL RUNS SHOWING A LITTLE BETTER AGREEMENT FOR THE SYSTEM
ON WEDNESDAY NIGHT AND THURSDAY...BUT DIVERGE A BIT LEADING INTO
NEXT WEEKEND. ALSO OF NOTE ARE SOME PRETTY BIG CHANGES FROM EARLIER
MODELS RUNS. LATEST 12Z RUNS OF GFS AND ECMWF ARE MUCH SLOWER AND
FURTHER SOUTH WITH THE CLOSED LOW SYSTEM...RESULTING IN LITTLE TO NO
IMPACT ACROSS OUR FORECAST AREA. WENT AHEAD AND REMOVED MENTION OF
POPS FOR WEDNESDAY GIVEN THE SLOWER TIMING. DECIDED TO KEEP MENTION
OF LOW CHANCE POPS MAINLY IN NORTHWEST IOWA ON THURSDAY GIVEN THE
RECENT INCONSISTENCIES BETWEEN MODEL RUNS...BUT DID TRIM BACK
COVERAGE AND QUITE A BIT FROM THE ALL BLEND...WHICH WAS BIASED FROM
THE 00Z ECMWF RUN. TEMPERATURES REMAIN QUITE MILD INTO THURSDAY...
BRINGING THE QUESTION OF PRECIPITATION TYPE IF THIS SYSTEM DOES
GRAZE OUR SOUTHEAST CWA. GIVEN WHAT LOOKS LIKE VERY MILD LOW/MID
LEVELS...PRECIPITATION TYPE MAY BECOME A CONCERN EARLY THURSDAY...
BUT WITH MANY FACTORS UP IN THE AIR...WILL KEEP IT SIMPLE WITH A
RAIN AND SNOW MIX.
THE NEXT AREA OF UNCERTAINTY IS REGARDING A STORM SYSTEM AROUND THE
SATURDAY TIME FRAME. MODELS CONTINUE TO FLIP FLOP WITH
SOLUTIONS...RESULTING IN LARGE TEMPERATURE AND POP DIFFERENCES. NOT
A WHOLE LOT OF CONFIDENCE...ESPECIALLY WITH THE VERY EXTREME GFS
SOLUTION. IT DOES LOOK LIKE A BIT OF A COOL DOWN FRIDAY AND SATURDAY
COMPARED TO EARLIER IN THE WEEK...BUT NOTHING TOO EXTREME. DID NOT
ALTER MUCH FROM THE ALLBLEND.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
545 PM CST SAT JAN 5 2013
.DISCUSSION.../ISSUED AT 342 PM CST/
UPPER WAVE PUSHING ACROSS THE DAKOTAS THIS AFTERNOON...DRIVING COLD
FRONT INTO THE FAR EASTERN PORTIONS OF THE STATE AT MID AFTERNOON.
CLOUDS PUSHING IN WITH STRONG COLD AIR ADVECTION...AND WITH OFF
SURFACE TEMPS FALLING QUICKLY TOWARD THOSE FAVORING ICE NUCLEATION...
HAVE SEEN FLURRIES DROP IN TO PARTS OF EAST CENTRAL SOUTH DAKOTA.
THE CLOUDS AND FLURRIES WILL CONTINUE TO PUSH EAST AND SOUTHEAST
THIS EVENING...BUT IT IS CERTAINLY A CHALLENGE AS TO HOW QUICKLY TO
BRING IN A MORE PERMANENT CLEARING. RAP AND 18Z NAM ARE NOW IN
FAVOR OF HANGING BACK A PERIOD OF LOWER CLOUDS LATER INTO THE NIGHT
NEAR/WEST OF THE JAMES RIVER AND THEN DRIFTING EAST AS FLOW ALOFT
STARTS TO TURN A BIT MORE WESTERLY. THIS ALSO PRESENTS A LARGE
CHALLENGE TO TEMPERATURES...WHICH WILL PROVE ALMOST IMPOSSIBLE TO
GET CLOSE ON AN HOURLY TIME FRAME WITH IN AND OUT CLOUD TRENDS.
EXPECT A BETTER PUSH OF CLEARING THROUGH THE EASTERN CWA BY LATER
EVENING...BUT ENOUGH WIND OR A FEW MORE CLOUDS LIKELY TO KEEP TEMPS
FROM PLUNGING TOO FAR ANYWHERE. GENERALLY LOOKING FOR QUITE A FEW
SINGLE DIGITS...WITH READINGS AROUND 10 WEST AS WARMER AIR SHUNTS
EAST FAIRLY QUICKLY.
SUNDAY AGAIN PRESENTS A SMALL CHALLENGE TO TEMPS...WITH A VERY
WEAK GRADIENT THROUGH MIDDAY OR EVEN EARLY AFTERNOON IN THE FAR
SOUTHEAST. LOWER ELEVATION LOCATIONS COULD EASILY ONCE AGAIN FIND
THEMSELVES MIRED IN CHILLIER AIR...WITH THE INCREASING SOUTHERLY
GRADIENT MAINLY ACROSS SOUTHEAST SOUTH DAKOTA AND INTO SOUTHWEST
MINNESOTA DURING THE AFTERNOON. HIGH CLOUDS PUSHING ACROSS WOULD
ONLY ENHANCE THE POTENTIAL FOR THIS TO OCCUR...SO WAS CAREFUL TO
NOT WARM CONDITIONS IN THE EAST TOO MUCH...AND DID NUDGE SOME
TEMPERATURES DOWN ACROSS PARTS OF NW IA. THE WEST WILL BE OPEN TO
SOME BETTER WARMING...BUT EVEN THERE THE INVERSION WILL PRESENT A
BIT OF A CHALLENGE TO LOWER ELEVATION WARMING. /CHAPMAN
THE PATTERN OF MILD WEATHER WILL CONTINUE THROUGH MUCH OF THE WEEK
AS A MORE ZONAL PATTERN SETS UP FOR THE FIRST HALF OF THE WORK WEEK.
MILDER WEST TO SOUTHWEST FLOW WILL MAKE TEMPERATURES QUITE TRICKY TO
PINPOINT...PARTICULARLY REGARDING OVERNIGHT LOWS. FOR SUNDAY
NIGHT...BREEZY SOUTH TO SOUTHWEST WINDS WILL LIKELY RESULT IN A
NON-DIURNAL TEMPERATURE TREND WITH LOWS EXPECTED IN THE EVENING OR
SHORTLY AFTER MIDNIGHT...THEN SLOWLY RISING LATE. THE QUESTION IS
HOW COOL WE WILL BE ABLE TO FALL OFF IN THE EVENING. OTHERWISE...
HIGH TEMPERATURES FOR TUESDAY AND WEDNESDAY WILL LIKELY BE NEAR OR
JUST ABOVE FREEZING...WITH THE HIGHS IN THE LOW 40S POSSIBLE IN
SOUTH CENTRAL SD WHERE THE GREATEST POTENTIAL MIXING OF THE MILD LOW
LEVEL TEMPERATURES COULD OCCUR.
LATEST MODEL RUNS SHOWING A LITTLE BETTER AGREEMENT FOR THE SYSTEM
ON WEDNESDAY NIGHT AND THURSDAY...BUT DIVERGE A BIT LEADING INTO
NEXT WEEKEND. ALSO OF NOTE ARE SOME PRETTY BIG CHANGES FROM EARLIER
MODELS RUNS. LATEST 12Z RUNS OF GFS AND ECMWF ARE MUCH SLOWER AND
FURTHER SOUTH WITH THE CLOSED LOW SYSTEM...RESULTING IN LITTLE TO NO
IMPACT ACROSS OUR FORECAST AREA. WENT AHEAD AND REMOVED MENTION OF
POPS FOR WEDNESDAY GIVEN THE SLOWER TIMING. DECIDED TO KEEP MENTION
OF LOW CHANCE POPS MAINLY IN NORTHWEST IOWA ON THURSDAY GIVEN THE
RECENT INCONSISTENCIES BETWEEN MODEL RUNS...BUT DID TRIM BACK
COVERAGE AND QUITE A BIT FROM THE ALL BLEND...WHICH WAS BIASED FROM
THE 00Z ECMWF RUN. TEMPERATURES REMAIN QUITE MILD INTO THURSDAY...
BRINGING THE QUESTION OF PRECIPITATION TYPE IF THIS SYSTEM DOES
GRAZE OUR SOUTHEAST CWA. GIVEN WHAT LOOKS LIKE VERY MILD LOW/MID
LEVELS...PRECIPITATION TYPE MAY BECOME A CONCERN EARLY THURSDAY...
BUT WITH MANY FACTORS UP IN THE AIR...WILL KEEP IT SIMPLE WITH A
RAIN AND SNOW MIX.
THE NEXT AREA OF UNCERTAINTY IS REGARDING A STORM SYSTEM AROUND THE
SATURDAY TIME FRAME. MODELS CONTINUE TO FLIP FLOP WITH
SOLUTIONS...RESULTING IN LARGE TEMPERATURE AND POP DIFFERENCES. NOT
A WHOLE LOT OF CONFIDENCE...ESPECIALLY WITH THE VERY EXTREME GFS
SOLUTION. IT DOES LOOK LIKE A BIT OF A COOL DOWN FRIDAY AND SATURDAY
COMPARED TO EARLIER IN THE WEEK...BUT NOTHING TOO EXTREME. DID NOT
ALTER MUCH FROM THE ALLBLEND.
&&
.AVIATION.../FOR THE 00Z TAF ISSUANCE/
MVFR STRATUS CONTINUES TO PROGRESS SOUTHWARD THROUGH THE CWA...
ALONG WITH LARGELY VFR-OCCASIONAL MVFR VISIBILITY IN -SN. MAIN AREA
OF STRATUS EXPECTED TO GRADUALLY CLEAR NORTH TO SOUTH THROUGH THE
NIGHT...WITH MAIN QUESTION BEING WHAT WILL HAPPEN WITH ELONGATED
NORTH-SOUTH BAND OF STRATUS EXTENDING THROUGH THE CENTRAL DAKOTAS AT
THE START OF THE PERIOD. RAP MODEL SEEMS TO HAVE BEST HANDLE ON
EXISTENCE OF THIS BAND...AND IT DEPICTS SOUTHERN END ERODING A BIT
AS THE BAND SWINGS EASTWARD THROUGH NORTHEAST PARTS OF OUR FORECAST
AREA AFTER 06Z. COULD SCRAPE KHON/KFSD WITH LOWER END MVFR TO IFR
CEILINGS 06Z-12Z WINDOW IF SOUTHERN END DOES NOT ERODE AS INDICATED
BUT WILL SIDE WITH DRYING IN THIS LAYER FOR NOW AND KEEP THESE TAFS
VFR AFTER 05Z/07Z RESPECTIVELY AS THE PRIMARY STRATUS AREA SHIFTS TO
THE SOUTH. OCCASIONAL NORTHWESTERLY WIND GUSTS 25-30KTS WILL LINGER
INTO THE EARLY PART OF THE TAF PERIOD...GRADUALLY SUBSIDING THROUGH
THE EVENING...WITH GUSTS EXPECTED TO DIMINISH ENTIRELY AS STRATUS
CLEARS.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML.
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
307 PM EST FRI JAN 4 2013
.SYNOPSIS...
SURFACE HIGH PRESSURE TONIGHT. TWO MID/UPPER LEVEL TROUGHS PASS THIS
WEEKEND. HIGH PRESSURE THEN BUILDS IN...MONDAY AND EARLY WEDNESDAY.
LOW PRESSURE BRINGS RAIN SHOWERS LATE WEDNESDAY NIGHT AND THURSDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
USED RAP AND VIS SAT TRENDS AS BASE FOR TIMING IMPROVING SKY
CONDITION INTO TONIGHT. THINK AREAS ALONG AND E OF I79 CORRIDOR
WILL KEEP CLDS WITH N MTNS HOLDING ON UNTIL PERHAPS 15Z. LOWS
TONIGHT TRICKY ONCE AGAIN AND WILL DEPEND ON EXTENT OF CLEARING
AND BL PUFF. LAMP GUIDANCE CONT TO BE ON WARM SIDE...LKLY OWING TO
BL PUFF AND ALSO CLDS ACROSS THE MTNS. DEEPER VALLEYS/HOLLOWS MAY
DECOUPLE THOUGH...GIVING UPPER TEENS. WILL LEAN TOWARD LAMP WHICH
HAS PERFORMED BETTER OVER RECENT COLD BIAS IN MET/MAV AND
INCORPORATE A COLDER SOLUTION FOR TYPICAL COLD SPOTS OUTSIDE OF
THE CLDS.
ANY REMAINING STRATUS ACROSS N MTNS WILL SCT OUT BY LATE
MORNING. SOME HIGH CLDS WILL BE ROLLING IN AFTN FROM SW...HELPING
TO PUT A FILTER ON SUNSHINE. KEPT POPS OUT THROUGH 00Z...WITH DRY
LLVLS IN PLACE. HOWEVER...MAY SEE ENOUGH TOP DOWN MOISTENING FOR
SOME LIGHT PCPN ACROSS SW VA BY 00Z.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
UPPER SPLIT FLOW PATTERN CONTINUES. MODELS IN GOOD AGREEMENT ON
SOUTHERN STREAM UPPER LOW OVER THE SOUTHWEST U.S. WEAKENING AS IT
OPENS UP...AND LIFTS NORTHEASTWARD ACROSS THE OHIO VALLEY SATURDAY
NIGHT IN CONFLUENT FLOW ALOFT. THIS SYSTEM IS FORECAST TO BE TOO
WEAK TO LIFT THE BAROCLINIC ZONE...STILL ACROSS THE SOUTHEASTERN
STATES...NORTHWARD ENOUGH TO AFFECT ALL BUT THE SOUTHEAST PORTION
OUR AREA. WITH THE VORT CENTER OF THE SYSTEM TRACKING ACROSS THE
MIDDLE OHIO VALLEY INTO THE GREAT LAKES...THE EFFECTS OF ITS
DYNAMICS WILL MAINLY CLIP OUR SOUTHEAST OHIO ZONES. THUS...AS A
WHOLE...OUR AREA LOOKS TO BE IN A MIN FOR QPF. WILL KEEP LOW POPS
ACROSS THE AREA SATURDAY NIGHT...WITH THE BEST CHANCE OVER THE
NORTHWEST AND SOUTHEAST AREAS. DRY SLOW MOVES IN BY SUNDAY MORNING
AS THE SOUTHERN STREAM SYSTEM DEPARTS WITH A BREAK IN THE PRECIP.
DURING SUNDAY...A NORTHERN STEAM UPPER TROUGH AND COLD FRONT DROPS
RAPIDLY SOUTHEAST ACROSS THE AREA SUNDAY AFTERNOON...BRINGING
SCATTERED RAIN SHOWERS...CHANGING TO SNOW SHOWERS BEFORE ENDING
SUNDAY NIGHT. AGAIN...EXPECT LIGHT QPF WITH ANY SNOW ACCUMULATIONS
LIMITED TO MAINLY THE NORTHERN MOUNTAINS...GENERALLY AN INCH OR TWO
BY MONDAY MORNING.
BEHIND THIS QUICK HITTER WILL BE HIGH PRESSURE FOR MONDAY WITH
INCREASING SUNSHINE. MAX TEMPERATURES SUNDAY AND MONDAY AFTERNOON
WILL BE SIMILAR IN THE LOW TO MID 40S...SUNDAY MAINLY
DUE TO THE CLOUDS AND MONDAY MAINLY DUE TO THE SUNSHINE.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
HIGH PRESSURE REMAINS IN CONTROL MONDAY NIGHT AND TUESDAY TO PROVIDE
DRY CONDITIONS.
A DEVELOPING LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST
WEDNESDAY NIGHT. DIFFERENCES BETWEEN THE ECMWF AND GFS EXIST. THE
ECMWF IS THE PREFERRED MODELS WITH A LOW LATITUDE CYCLONE BECOMING
LESS PROGRESSIVE...WITH SFC LOW TRACK MOVING FROM THE CENTRAL PLAINS
NORTHEAST INTO THE GREAT LAKES REGION...CONTRARY TO THE GFS THAT
DEVELOPS THE LOW OVER THE SOUTHERN PLAINS...TRACKING THE LOW
OVERHEAD WV.
THEREFORE...MINOR TWEAKS WHERE NEEDED FROM PREVIOUS FORECAST...WITH
CHANCES OF RAIN SHOWERS SPREADING FROM WEST TO EAST LATE WEDNESDAY
NIGHT...WITH THE BULK OF PCPN OCCURRING ON THURSDAY.
TEMPERATURE PROFILES AND BOUNDARY LAYER SOUTHWEST FLOW SUGGEST ALL
PCPN STARTING AS LIQUID BY 15Z THURSDAY. THEREFORE...HIGHEST POPS
WHERE CODED ON THURSDAY. ECMWF H850 STRENGTHENING SOUTH TO SOUTHWEST
FLOW AROUND 50 KNOTS...AND TEMPERATURES NEAR 11C BY 18Z
THURSDAY...SUPPORT A GRADUAL WARMING TREND THRU THURSDAY AFTERNOON.
DECREASED POPS BY 06Z FRIDAY...WITH CHANCE POPS MAINLY OVER NORTHERN
AND EASTERN MOUNTAINS. DRIER AIR MASS EXPECTED BY MID FRIDAY MORNING
WITH PCPN EXITING NORTHEAST.
WENT GENERALLY WITH HPC GUIDANCE FOR TEMPERATURES ADDING FEW LOCAL
DETAILS.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
FOR NE KY/SE OH/SW VA...MVFR STRATOCU WILL CONT TO LIFT INTO LOW END
VFR AND BECOME SCT AFTER SUNSET. ELSEWHERE...WILL CARRY MVFR CIGS
UNTIL LATE AFTN/EARLY EVE...KEEPING KEKN IN MOST OF THE NIGHT. WILL
ALSO ALLOW FOR A RETURN TO BKN MVFR FOR KCKB AFTER 09Z WITH AREA OF
LLVL MOISTURE SWINGING DOWN FROM N. SFC WINDS WILL SLACKEN THIS
EVE...BUT STILL CARRY WESTERLY A LIGHT WIND OVERNIGHT.
VFR CONDITIONS AREAWIDE AFTER 15Z WITH SOME HI CLDS ROLLING IN
FROM SW AFTER 18Z.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SATURDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING OF BREAKUP OF STRATUS DECK MAY VARY
THIS EVENING.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
EST 1HRLY 15 16 17 18 19 20 21 22 23 00 01 02
CRW CONSISTENCY M M M M M M M M M M M M
HTS CONSISTENCY M M M M M M M M M M M M
BKW CONSISTENCY H H H M M M M M M M M M
EKN CONSISTENCY M M M M M M M M M M M M
PKB CONSISTENCY M M M M M M M M M M M M
CKB CONSISTENCY M M M M M M M M M M M M
AFTER 18Z SATURDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/JMV/30
NEAR TERM...30
SHORT TERM...JMV
LONG TERM...ARJ
AVIATION...30
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
127 PM EST FRI JAN 4 2013
.SYNOPSIS...
SURFACE HIGH PRESSURE BUILDS IN TONIGHT. TWO MID/UPPER LEVEL
TROUGHS PASS THIS WEEKEND. HIGH PRESSURE THEN BUILDS IN...AND
DOMINATES FOR MONDAY AND TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
USED RAP AND VIS SAT TRENDS AS BASE FOR TIMING IMPROVING SKY
CONDITION INTO TONIGHT. THINK AREAS ALONG AND E OF I79 CORRIDOR
WILL KEEP CLDS WITH N MTNS HOLDING ON UNTIL PERHAPS 15Z. LOWS
TONIGHT TRICKY ONCE AGAIN AND WILL DEPEND ON EXTENT OF CLEARING
AND BL PUFF. LAMP GUIDANCE CONT TO BE ON WARM SIDE...LKLY OWING TO
BL PUFF AND ALSO CLDS ACROSS THE MTNS. DEEPER VALLEYS/HOLLOWS MAY
DECOUPLE THOUGH...GIVING UPPER TEENS. WILL LEAN TOWARD LAMP WHICH
HAS PERFORMED BETTER OVER RECENT COLD BIAS IN MET/MAV AND
INCORPORATE A COLDER SOLUTION FOR TYPICAL COLD SPOTS OUTSIDE OF
THE CLDS.
ANY REMAINING STRATUS ACROSS N MTNS WILL SCT OUT BY LATE
MORNING. SOME HIGH CLDS WILL BE ROLLING IN AFTN FROM SW...HELPING
TO PUT A FILTER ON SUNSHINE. KEPT POPS OUT THROUGH 00Z...WITH DRY
LLVLS IN PLACE. HOWEVER...MAY SEE ENOUGH TOP DOWN MOISTENING FOR SOME LIGHT
PCPN ACROSS SW VA BY 00Z.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
2 MID/UPPER LEVEL DISTURBANCES PASS...ONE OVERNIGHT SATURDAY
NIGHT...THE OTHER SUNDAY NIGHT. A WEAK SURFACE COLD FRONT
ASSOCIATED WITH THE 2ND ONE. BOTH SYSTEMS DEALING WITH PRECIPITABLE
WATER MAXIMUM OF AROUND .4 TO .5 INCHES.
THE ONLY SIGNIFICANT CHANGE MADE TO OUR FORECAST WAS TO SLOW DOWN
THE INCREASE IN POPS A BIT FOR SUNDAY...WITH THE PEAK OF THE LIMITED
MOISTURE SWEEPING THROUGH SUNDAY EVENING. LEFT SOUTHERN COUNTIES
WITH POP AOB 14 PCT FOR SUNDAY MORNING...BEFORE INCREASING LATER IN
THE DAY. WAS ALSO A BIT SLOWER ENDING THE SNOW SHOWERS IN THE
CENTRAL WV MOUNTAINS OVERNIGHT SUNDAY NIGHT.
STILL DRY MONDAY INTO TUESDAY. LOWERED MAXIMUM TEMPERATURE MONDAY A
BIT...FIGURING MAIN WARM UP ARRIVES TUESDAY.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
BASED ON SURROUNDING OFFICES AND 00Z MODELS...MADE A MINOR CHANGE IN
EXTENDED...TO INTRODUCE POPS A FASTER WEDNESDAY NIGHT. 00Z GFS THE
FASTEST WITH THE PCPN SINCE ITS MID LEVEL CIRCULATION NOT AS STRONG
AS ECMWF. YET...DID NOT JUMP ON THE GFS SPEED AS THIS TIME...BUT
TRENDED A BIT FASTER. SHOULD BE MOSTLY RAIN.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
FOR NE KY/SE OH/SW VA...MVFR STRATOCU WILL CONT TO LIFT INTO LOW END
VFR AND BECOME SCT AFTER SUNSET. ELSEWHERE...WILL CARRY MVFR CIGS UNTIL
LATE AFTN/EARLY EVE...KEEPING KEKN IN MOST OF THE NIGHT. WILL ALSO
ALLOW FOR A RETURN TO BKN MVFR FOR KCKB AFTER 09Z WITH AREA OF
LLVL MOISTURE SWINGING DOWN FROM N. SFC WINDS WILL SLACKEN THIS
EVE...BUT STILL CARRY WESTERLY A LIGHT WIND OVERNIGHT.
VFR CONDITIONS AREAWIDE AFTER 15Z WITH SOME HI CLDS ROLLING IN
FROM SW AFTER 18Z.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SATURDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING OF BREAKUP OF STRATUS DECK MAY VARY
THIS EVENING.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EST 1HRLY 13 14 15 16 17 18 19 20 21 22 23 00
CRW CONSISTENCY H M M M M M M H H H H H
HTS CONSISTENCY H M M M M M M H H H H H
BKW CONSISTENCY H M M M M M M H H H H H
EKN CONSISTENCY H M M M M M M H H H H H
PKB CONSISTENCY M M M M M M M H H H H H
CKB CONSISTENCY H H M M M M M H H H H H
AFTER 18Z SATURDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/JMV/30
NEAR TERM...30
SHORT TERM...KTB
LONG TERM...ARJ
AVIATION...30
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
936 AM EST FRI JAN 4 2013
.SYNOPSIS...
SURFACE HIGH PRESSURE BUILDS IN FOR TONIGHT. TWO MID/UPPER LEVEL
TROUGHS PASS THIS WEEKEND. HIGH PRESSURE THEN BUILDS IN...AND
DOMINATES FOR MONDAY AND TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
930AM UPDATE...
STRATOCU SHOWING SIGNS OF SCT OUT ACROSS SE OH AND GREENBRIER
VALLEY AS CLOSED H5 LOW APPROACHES. NOT EXPECTING ANYTHING WITH
THIS OTHER THAN TO HELP TO SCT OUT CLDS. USED RAP AS BASE FOR
TIMING IMPROVING SKY CONDITION TDY...HEDGING SOMEWHAT QUICKER ON
WESTERN FLANKS. THINK AREAS ALONG AND E OF I79 CORRIDOR MAY
STRUGGLE TO SEE ANY PEAKS OF SUN. TWEAKED TEMPS TODAY USING LATEST
LAMP GUIDANCE WHICH RESULTED IN KNOCKING DOWN HIGHS A TICK. STILL
EXPECTING SOME GUSTY WINDS THIS AFTN...PARTICULARLY FOR LOCALES
THAT CAN RID THEMSELVES OF CLDS AND ALSO IN MTNS.
PREVIOUS DISCUSSION BELOW...
STRATUS DECK CURRENTLY IN PLACE ACROSS THE FORECAST AREA...WITH A
FEW REPORTS OF FLURRIES OR LIGHT SNOW. THINK THE CHANCE FOR
MEASURABLE PRECIPITATION IS FAIRLY LIMITED...BUT WILL LINGER SOME
SLIGHT CHANCE POPS ACROSS THE NORTHERN MOUNTAINS EARLY THIS MORNING.
CLOUDS WILL GRADUALLY BREAK UP FROM WEST TO EAST THROUGH THE
DAY AS...LINGERING IN THE NORTHERN MOUNTAINS THE LONGEST. A VERY
MOISTURE STARVED 500 MB LOW WILL CROSS THE AREA THIS AFTERNOON
TODAY. WITH HIGH PRESSURE MOVING IN AT THE SURFACE...DO NOT EXPECT
ANYTHING FROM THE UPPER LEVEL WAVE...IF ANYTHING IT MAY INCREASE
MIXING AND HELP THE DRY AIR ERODE THE LAYER OF CLOUDS LATER TODAY.
00Z GFS DOES TRY TO SHOW SOME PRECIP THROUGH THIS AFTERNOON...BUT
ITS THE ONLY ONE SO WILL KEEP FORECAST DRY. BOUNDARY LAYER WINDS
BECOME A BIT BREEZY TODAY AND TONIGHT...SO LOOKING AT SW WINDS
PICKING UP TODAY...AND LINGERING INTO TONIGHT.
STAYED BELOW MAV/MET GUIDANCE FOR HIGHS TODAY AS 850 THERMAL TROUGH
SLIDES THROUGH. GOING JUST A BIT COOLER THAN THURSDAY...WITH MID TO
UPPER 30S ACROSS THE LOWLANDS...AND 20S TO LOW 30S IN THE HIGHER
TERRAIN. 850S BEGIN WARMING OVERNIGHT...BUT LATE ENOUGH TO REALLY
ONLY HAVE IMPACTS IN THE HIGHER TERRAIN WHERE WE COULD SEE SOME
GRADUAL PRE-DAWN WARMING ABOVE 2500-3000 FEET. ONLY MADE MINOR
TWEAKS TO THE LOWS FOR TONIGHT...WITH GENERALLY TEENS TO LOW 20S
ACROSS THE BOARD.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
2 MID/UPPER LEVEL DISTURBANCES PASS...ONE OVERNIGHT SATURDAY
NIGHT...THE OTHER SUNDAY NIGHT. A WEAK SURFACE COLD FRONT
ASSOCIATED WITH THE 2ND ONE. BOTH SYSTEMS DEALING WITH PRECIPITABLE
WATER MAXIMUM OF AROUND .4 TO .5 INCHES.
THE ONLY SIGNIFICANT CHANGE MADE TO OUR FORECAST WAS TO SLOW DOWN
THE INCREASE IN POPS A BIT FOR SUNDAY...WITH THE PEAK OF THE LIMITED
MOISTURE SWEEPING THROUGH SUNDAY EVENING. LEFT SOUTHERN COUNTIES
WITH POP AOB 14 PCT FOR SUNDAY MORNING...BEFORE INCREASING LATER IN
THE DAY. WAS ALSO A BIT SLOWER ENDING THE SNOW SHOWERS IN THE
CENTRAL WV MOUNTAINS OVERNIGHT SUNDAY NIGHT.
STILL DRY MONDAY INTO TUESDAY. LOWERED MAXIMUM TEMPERATURE MONDAY A
BIT...FIGURING MAIN WARM UP ARRIVES TUESDAY.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
BASED ON SURROUNDING OFFICES AND 00Z MODELS...MADE A MINOR CHANGE IN
EXTENDED...TO INTRODUCE POPS A FASTER WEDNESDAY NIGHT. 00Z GFS THE
FASTEST WITH THE PCPN SINCE ITS MID LEVEL CIRCULATION NOT AS STRONG
AS ECMWF. YET...DID NOT JUMP ON THE GFS SPEED AS THIS TIME...BUT
TRENDED A BIT FASTER. SHOULD BE MOSTLY RAIN.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
MVFR CEILING IN PLACE ACROSS MOST OF CWA...EXCEPT FOR VERY
SOUTHERN TIP. LINGERED THE LOWER CLOUDS LONGER THAN PREVIOUS
FORECAST...ERODING FROM WEST TO EAST LATE MORNING INTO THE
AFTERNOON...AND LINGERING INTO THE EVENING ACROSS THE NORTHERN
MOUNTAINS. COULD EVEN GET SOME VERY ISOLATED LIGHT
SNOW/FLURRIES...MAINLY IN THE NORTHERN MOUNTAINS UNTIL CLOUDS
BREAK UP. VFR SHOULD THEN PREVAIL THROUGH THE REMAINDER OF THE TAF
PERIOD.
SURFACE FLOW TO INCREASE OUT OF THE WEST SOUTHWEST TODAY WITH
GUSTS TO AROUND 20-25KTS IN THE AFTERNOON WITH MIXING.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SATURDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING OF BREAKUP OF STRATUS DECK MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EST 1HRLY 09 10 11 12 13 14 15 16 17 18 19 20
CRW CONSISTENCY H H H M M M M M M M M H
HTS CONSISTENCY H H H M M M M M M M M H
BKW CONSISTENCY H H M M M M M M M M M H
EKN CONSISTENCY L L H H H M M M M M M H
PKB CONSISTENCY L L H H M M M M M M M H
CKB CONSISTENCY L L L M M M M M M M M H
AFTER 12Z SATURDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/ARJ/MZ
NEAR TERM...MZ/30
SHORT TERM...KTB
LONG TERM...ARJ
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
645 PM CST SAT JAN 5 2013
.SHORT TERM...TONIGHT
645 PM CST SAT JAN 5 2013
HAVE MADE SOME UPDATES TO THE FORECAST THIS EVENING WITH THE
PROSPECTS FOR DRIZZLE/FREEZING DRIZZLE. FIRST...TEMPERATURES HAVE
REMAINED ABOVE FREEZING IN THE WARM SECTOR AHEAD OF THE COLD FRONT
THAT CURRENTLY RUNS THROUGH NORTHEAST IOWA UP TO A TRIPLE POINT IN
WESTERN WISCONSIN WITH A WARM FRONT EXTENDING EAST ACROSS
WISCONSIN TOWARD GREEN BAY. CEILINGS FROM NORTHEAST IOWA INTO
SOUTHWEST WISCONSIN HAVE NOT BEEN AS LOW AS YOU WOULD WANT FOR
DRIZZLE TO OCCUR WITH THEM BEING AT 2-4KFT. OBSERVATIONS FROM DOWN
IN THIS REGION ALL SHOW VISIBILITY UP AT GREATER THAN 6SM WITH NO
REPORTS OF DRIZZLE THIS AFTERNOON/EARLY EVENING. 05.22Z RAP
SOUNDINGS OUT OF DBQ SEEM TO PAINT THE PICTURE WELL WITH A
SATURATED...PROBABLY OVERLY SATURATED...LOW LEVEL WITH NO VERTICAL
MOTIONS. BASED ON THESE FACTORS...HAVE REMOVED THE FREEZING
DRIZZLE/DRIZZLE MENTION FOR THIS EVENING.
THE SECOND WAVE THEN COMES IN AS A SECONDARY COLD FRONT WHICH
CURRENTLY IS DROPPING SOUTH ON THE BACK SIDE OF THE SURFACE LOW
ACROSS SOUTHERN MINNESOTA. THERE IS A BRIEF PERIOD OF
CLEARING...BUT THEN THERE IS A PATCH OF LOW LEVEL CLOUD COVER
TRACKING TO THE SOUTHEAST FROM SOUTH DAKOTA INTO CENTRAL IOWA.
MODELS HAVE BEEN OVER-DOING THE LOW LEVEL MOISTURE WITH THIS
FEATURE AND SHOW THAT WE SHOULD BE COMPLETELY OVERCAST AT THIS
POINT. HAVE LEFT SKY CONDITIONS AS MOSTLY CLOUDY TO CLOUDY
TONIGHT...BUT THAT MAY BE ON THE PESSIMISTIC SIDE GIVEN CURRENT
UPSTREAM CONDITIONS. 05.22Z RAP SOUNDINGS DO SHOW THAT IF THE LOW
LEVEL DECK DOES OCCUR THAT IT SHOULD BECOME COLDER THAN -8C THAT
ICE WOULD BE INTRODUCED. WITH WEAK FORCING...SHOULD SEE SOME
FLURRIES/SNOW SHOWERS WITH IT. THE LOW VISIBILITIES CURRENTLY
OCCURRING IN WEST CENTRAL MINNESOTA ARE FROM SNOW SHOWERS THOUGH
THEY ARE NOT SHOWING UP ON RADAR BECAUSE THE CLOUD DECK IS JUST A
FEW HUNDRED FEET OFF THE GROUND AND BELOW THE RADAR BEAM. THIS
AREA APPEARS TO BE RUNNING SOUTH OF THE FORECAST AREA...BUT WILL
HAVE TO MONITOR IT FOR WHETHER SOME SMALL ACCUMULATIONS NEED TO BE
ADDED OVERNIGHT.
.LONG TERM...TUESDAY THROUGH SATURDAY
201 PM CST SAT JAN 5 2013
MEDIUM RANGE MODELS HAVE STARTED TO COME INTO BETTER AGREEMENT
WITH THE SYSTEM EXPECTED TO IMPACT THE GREAT LAKES FOR THE LATTER
HALF OF THE WEEK. THE 05.00Z ECMWF HAS REMAINED CONSISTENT WITH
ITS PREVIOUS RUNS ON THE TRACK OF THE SYSTEM WHILE THE 05.12Z GFS
HAS SHIFTED CONSIDERABLY TOWARD THE ECMWF SOLUTION. THE MODELS ARE
NOW VERY SIMILAR IN TIMING BUT THE GFS STILL DOES NOT BRING THE
SYSTEM AS FAR NORTH AS THE ECMWF. BY 11.00Z /FRIDAY EVENING/ THE
ECMWF PLACES THE UPPER LEVEL LOW NEAR THE WISCONSIN-ILLINOIS
BORDER BETWEEN KDBQ AND KRST WHILE THE GFS IS FARTHER SOUTH NEAR
KSTL. THE AGREEMENT THAT WAS IN PLACE HAS BEEN THROWN OUT THE
WINDOW BY THE 05.12Z ECMWF HAS IT HAS COME IN SLOWER AND FARTHER
SOUTH AND IS NOT SIMILAR WITH ITS TRACK TO THE GFS. WITH THE
DISPARITY BETWEEN THE MODELS...THE ONLY CHANGE MADE TO THE MODEL
CONSENSUS GRIDS WAS TO WEDNESDAY NIGHT. WITH THE ECMWF NOW BEING
SLOWER...IT SUGGESTS THE PRECIPITATION WILL NOT MOVE IN UNTIL
THURSDAY...SO WILL NOW GO WITH A DRY WEDNESDAY NIGHT. THE
PRECIPITATION FROM THIS SYSTEM SHOULD START TO MOVE OUT THURSDAY
NIGHT OR FRIDAY BUT WILL QUICKLY BE FOLLOWED BY THE NEXT SYSTEM.
THE MODELS MAINTAIN A SOUTHWEST FLOW ALOFT BEHIND THIS SYSTEM AND
QUICKLY EJECT OUT ANOTHER SYSTEM FROM THE SOUTHERN ROCKIES. THE
ECMWF IS QUICKER AND FARTHER NORTH THAN THE GFS IN THE UPPER
LEVELS...BUT THE SURFACE TRACKS LOOK TO BE SIMILAR GOING FROM NEAR
KMCI TOWARD KMKE EITHER SATURDAY OR SATURDAY NIGHT. THE ECMWF
SUGGESTS THE FIRST SYSTEM WILL BRING ENOUGH WARM AIR NORTH TO
PRODUCE PRIMARILY RAIN OR A RAIN/SNOW MIX. HOWEVER...THE
BAROCLINIC ZONE LEFT BEHIND MAY BE JUST TO THE SOUTHEAST GIVING
THE SECOND SYSTEM ENOUGH COLD AIR TO WORK WITH TO PRODUCE MAINLY
SNOW.
&&
.AVIATION...TONIGHT AND SUNDAY
541 PM CST SAT JAN 5 2013
THE FOCUS INTO TOMORROW IS WITH THE PERIODIC LOW CEILINGS THAT
WILL OCCUR INTO TOMORROW MORNING. THE FIRST SYSTEM IS CURRENTLY
MOVING THROUGH NORTHERN ILLINOIS AND HAS BROUGHT SOME 2-3KFT BKN
TO OVC CEILINGS UP ACROSS NORTHEAST IOWA...FAR SOUTHEAST MINNESOTA
AND SOUTHWEST WISCONSIN. HIGH LEVEL CLOUDS ARE CURRENTLY
OBSCURING THE VIEW OF THE LOW LEVEL CLOUDS ON SATELLITE...BUT
SOME OBSERVATIONS IN SOUTHEAST MINNESOTA HAVE BEEN SHOWING THAT
THAT WESTERN EDGE OF THE DECK IS SLOWLY MOVING EAST. DECIDED TO
PLAY IT PESSIMISTIC WITH KEEPING THE MVFR CEILINGS IN AT LSE
THROUGH THE NIGHT...BUT THERE COULD BE A BRIEF PERIOD WHERE IT
JUMPS UP TO VFR THIS EVENING.
OTHERWISE...A COLD FRONT WILL MOVE THROUGH LATER THIS EVENING WITH
WINDS COMING AROUND TO THE NORTHWEST AND ANOTHER BAND OF MVFR TO
IFR CEILINGS EXPECTED TO LAST THROUGH THE OVERNIGHT HOURS.
SATELLITE SHOWS THAT THESE CEILINGS ARE FAIRLY SCATTERED TO
BROKEN AT THIS POINT...BUT FORECAST GUIDANCE IS SHOWING A RAPID
MOISTENING OF THE LOW LEVELS THIS EVENING. SO...WILL MAINTAIN THE
FORECAST...BUT CONFIDENCE IS NOT AS HIGH THAT THESE LOW CEILINGS
WILL BE AS PREVALENT AS ADVERTISED. CONDITIONS WILL IMPROVE
TOMORROW MORNING AS DRIER AIR MOVES IN ON THE BACK SIDE OF THIS
SYSTEM.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
201 PM CST SAT JAN 5 2013
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...04
AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
541 PM CST SAT JAN 5 2013
.SHORT TERM...THROUGH MONDAY NIGHT
201 PM CST SAT JAN 5 2013
MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES TONIGHT.
SURFACE ANALYSIS EARLY THIS AFTERNOON SHOWS AN AREA OF LOW
PRESSURE OVER NORTHEAST MINNESOTA NEAR KDLH WITH A COLD FRONT
EXTENDING SOUTHWEST INTO KANSAS.
WATER VAPOR SATELLITE SHOWING THREE SYSTEMS THAT WILL IMPACT THE
REGION TONIGHT. UPPER LEVEL LOW AND SHORT WAVE TROUGH MOVING
ACROSS NORTHERN MISSOURI WILL CONTINUE TO MOVE OFF TO THE
EAST/NORTHEAST TONIGHT TOWARD LAKE ERIE. AS IT DOES...A SHORT WAVE
TROUGH OVER SOUTH DAKOTA WILL MOVE SOUTHEAST ACROSS IOWA INTO THE
OHIO RIVER VALLEY. THIS WAVE WILL RAPIDLY PUSH THE SURFACE LOW AND
COLD FRONT ACROSS THE REGION THROUGH THE REMAINDER OF THE
AFTERNOON AND THIS EVENING. THE THIRD SHORT WAVE TROUGH IS MOVING
INTO NORTH DAKOTA FROM MANITOBA AND IS EXPECTED TO MOVE RIGHT
TOWARD THE AREA THROUGH THE NIGHT. THE FIRST SYSTEM IS EXPECTED TO
PASS BY FAR ENOUGH TO THE SOUTH TO NOT HAVE AN IMPACT ON THE AREA.
HOWEVER...THE SECOND SHORT WAVE TROUGH AND SURFACE SYSTEM MAY HAVE
ENOUGH GOING TO POSSIBLY PRODUCE SOME LIGHT FREEZING DRIZZLE ALONG
AND AHEAD OF THE COLD FRONT. THE 05.12Z NAM SHOWS SOME WEAK
OMEGA...ON THE ORDER OF ABOUT 1 UBAR/S...IN THE 0-2 KM LAYER WHERE
SOME WARM AIR ADVECTION WILL BE OCCURRING IN THE SOUTHWEST FLOW
AHEAD OF THE COLD FRONT. THE NAM AND 05.16Z RAP BUFKIT SOUNDINGS
SHOW THE LOW LEVELS SATURATING UP TO BETWEEN 2 AND 3 KM BEFORE THE
FRONT COMES THROUGH. HOWEVER...SOMEWHAT CONCERNED THAT THE BEST
LIFT MAY BE NEAR THE TOP OR JUST ABOVE THE SATURATED LAYER AND
THUS MAY NOT BE ABLE TO PRODUCE A WHOLE LOT OF DRIZZLE. STILL
ENOUGH OF A CONCERN TO KEEP THE LOW CHANCES FOR THE FREEZING
DRIZZLE AND NO CHANGES ARE PLANNED TO THE CURRENT FORECAST.
THE THIRD SHORT WAVE TROUGH IS PRODUCING SOME REPORTS OF LIGHT
SNOW ACROSS NORTH DAKOTA AND SOUTHERN MANITOBA WITH MVFR
VISIBILITIES. HOWEVER...THESE REPORTS ARE VERY SPORADIC WITH NOT
MUCH AREAL COVERAGE. THE FORECAST SOUNDINGS DO NOT SHOW THIS WAVE
PRODUCING MUCH OMEGA TONIGHT AS IT APPROACHES BUT IT SHOULD
PRODUCE UP TO 12 PVU/S OF VORTICITY ADVECTION IN THE 500-300 MB
LAYER. SOMEWHAT CONCERNED THAT THE MODELS MAY BE UNDERDONE WITH
THE AMOUNT OF LIFT THIS WAVE WILL PRODUCE AND THAT IT COULD END UP
PRODUCING A PERIOD OF VERY LIGHT SNOW BUT WILL MAINTAIN THE
FLURRIES AS THERE IS SOME QUESTION AS TO WHETHER THE MID LEVELS
WILL SATURATE ENOUGH TO ALLOW FOR ANYTHING MORE THAN FLURRIES.
AFTER THIS WAVE MOVES BY...QUIET AND WARMER WEATHER WILL SET UP
OVER THE REGION. THE SURFACE HIGH THAT WILL BE OVER THE REGION
SUNDAY WILL MOVE OFF TO THE EAST SUNDAY NIGHT AS A SYSTEM ROLLS
ACROSS SOUTHERN CANADA. THE PRECIPITATION FROM THIS SYSTEM WILL
STAY WELL TO THE NORTH BUT IT WILL HELP DRAW WARMER AIR IN WITH
HIGHS MONDAY EXPECTED TO TOP OUT IN THE LOWER 30S ACROSS THE
ENTIRE AREA.
.LONG TERM...TUESDAY THROUGH SATURDAY
201 PM CST SAT JAN 5 2013
MEDIUM RANGE MODELS HAVE STARTED TO COME INTO BETTER AGREEMENT
WITH THE SYSTEM EXPECTED TO IMPACT THE GREAT LAKES FOR THE LATTER
HALF OF THE WEEK. THE 05.00Z ECMWF HAS REMAINED CONSISTENT WITH
ITS PREVIOUS RUNS ON THE TRACK OF THE SYSTEM WHILE THE 05.12Z GFS
HAS SHIFTED CONSIDERABLY TOWARD THE ECMWF SOLUTION. THE MODELS ARE
NOW VERY SIMILAR IN TIMING BUT THE GFS STILL DOES NOT BRING THE
SYSTEM AS FAR NORTH AS THE ECMWF. BY 11.00Z /FRIDAY EVENING/ THE
ECMWF PLACES THE UPPER LEVEL LOW NEAR THE WISCONSIN-ILLINOIS
BORDER BETWEEN KDBQ AND KRST WHILE THE GFS IS FARTHER SOUTH NEAR
KSTL. THE AGREEMENT THAT WAS IN PLACE HAS BEEN THROWN OUT THE
WINDOW BY THE 05.12Z ECMWF HAS IT HAS COME IN SLOWER AND FARTHER
SOUTH AND IS NOT SIMILAR WITH ITS TRACK TO THE GFS. WITH THE
DISPARITY BETWEEN THE MODELS...THE ONLY CHANGE MADE TO THE MODEL
CONSENSUS GRIDS WAS TO WEDNESDAY NIGHT. WITH THE ECMWF NOW BEING
SLOWER...IT SUGGESTS THE PRECIPITATION WILL NOT MOVE IN UNTIL
THURSDAY...SO WILL NOW GO WITH A DRY WEDNESDAY NIGHT. THE
PRECIPITATION FROM THIS SYSTEM SHOULD START TO MOVE OUT THURSDAY
NIGHT OR FRIDAY BUT WILL QUICKLY BE FOLLOWED BY THE NEXT SYSTEM.
THE MODELS MAINTAIN A SOUTHWEST FLOW ALOFT BEHIND THIS SYSTEM AND
QUICKLY EJECT OUT ANOTHER SYSTEM FROM THE SOUTHERN ROCKIES. THE
ECMWF IS QUICKER AND FARTHER NORTH THAN THE GFS IN THE UPPER
LEVELS...BUT THE SURFACE TRACKS LOOK TO BE SIMILAR GOING FROM NEAR
KMCI TOWARD KMKE EITHER SATURDAY OR SATURDAY NIGHT. THE ECMWF
SUGGESTS THE FIRST SYSTEM WILL BRING ENOUGH WARM AIR NORTH TO
PRODUCE PRIMARILY RAIN OR A RAIN/SNOW MIX. HOWEVER...THE
BAROCLINIC ZONE LEFT BEHIND MAY BE JUST TO THE SOUTHEAST GIVING
THE SECOND SYSTEM ENOUGH COLD AIR TO WORK WITH TO PRODUCE MAINLY
SNOW.
&&
.AVIATION...TONIGHT AND SUNDAY
541 PM CST SAT JAN 5 2013
THE FOCUS INTO TOMORROW IS WITH THE PERIODIC LOW CEILINGS THAT
WILL OCCUR INTO TOMORROW MORNING. THE FIRST SYSTEM IS CURRENTLY
MOVING THROUGH NORTHERN ILLINOIS AND HAS BROUGHT SOME 2-3KFT BKN
TO OVC CEILINGS UP ACROSS NORTHEAST IOWA...FAR SOUTHEAST MINNESOTA
AND SOUTHWEST WISCONSIN. HIGH LEVEL CLOUDS ARE CURRENTLY
OBSCURING THE VIEW OF THE LOW LEVEL CLOUDS ON SATELLITE...BUT
SOME OBSERVATIONS IN SOUTHEAST MINNESOTA HAVE BEEN SHOWING THAT
THAT WESTERN EDGE OF THE DECK IS SLOWLY MOVING EAST. DECIDED TO
PLAY IT PESSIMISTIC WITH KEEPING THE MVFR CEILINGS IN AT LSE
THROUGH THE NIGHT...BUT THERE COULD BE A BRIEF PERIOD WHERE IT
JUMPS UP TO VFR THIS EVENING.
OTHERWISE...A COLD FRONT WILL MOVE THROUGH LATER THIS EVENING WITH
WINDS COMING AROUND TO THE NORTHWEST AND ANOTHER BAND OF MVFR TO
IFR CEILINGS EXPECTED TO LAST THROUGH THE OVERNIGHT HOURS.
SATELLITE SHOWS THAT THESE CEILINGS ARE FAIRLY SCATTERED TO
BROKEN AT THIS POINT...BUT FORECAST GUIDANCE IS SHOWING A RAPID
MOISTENING OF THE LOW LEVELS THIS EVENING. SO...WILL MAINTAIN THE
FORECAST...BUT CONFIDENCE IS NOT AS HIGH THAT THESE LOW CEILINGS
WILL BE AS PREVALENT AS ADVERTISED. CONDITIONS WILL IMPROVE
TOMORROW MORNING AS DRIER AIR MOVES IN ON THE BACK SIDE OF THIS
SYSTEM.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
201 PM CST SAT JAN 5 2013
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
233 PM CST FRI JAN 4 2013
.SHORT TERM...TONIGHT THROUGH MONDAY
233 PM CST FRI JAN 4 2013
MAIN FORECAST CONCERNS ARE ON LIGHT PRECIPITATION CHANCES SATURDAY
AFTERNOON INTO SATURDAY NIGHT.
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING ALONG THE WEST COAST OF THE U.S. INTO BRITISH
COLUMBIA...AN UPPER LOW OVER NEW MEXICO...A SHORTWAVE TROUGH OVER
SOUTHERN ALBERTA...WEAK RIDGING OVER THE DAKOTAS AND DEEP TROUGHING
OVER EASTERN CANADA. THE FORECAST AREA WAS UNDER SUBSIDENCE ALOFT
BEING IN NORTHWEST FLOW AHEAD OF THE DAKOTAS RIDGING...RESULTING IN
CLEAR SKIES. IN FACT...MAINLY CLEAR SKIES ENCOMPASS MUCH OF THE
UPPER MIDWEST DUE TO PLENTY OF DRY AIR...SEEN ON 12Z SOUNDINGS FROM
BIS...OAX...MPX AND GRB. ONE THING OF INTEREST ON ALL OF THOSE
SOUNDINGS IS A STRONG AND NEARLY SATURATED INVERSION BETWEEN
925-950MB. AGAIN...DESPITE THE NEAR SATURATION...SKIES ARE STILL
CLEAR. SUNSHINE PLUS THE 925MB TEMPS STARTING OFF IN THE -3 TO -6C
RANGE AT 12Z FROM SOUNDING DATA AND DRY AIR HAS ALLOWED TEMPERATURES
TO CLIMB INTO THE MID 20S TO LOW 30S. TO THE NORTHWEST...HIGH
CLOUDS WERE SPREADING ACROSS SASKATCHEWAN AND NORTH DAKOTA AHEAD
OF THE SOUTHERN ALBERTA SHORTWAVE TROUGH. IN ADDITION...AN AREA OF
LOW PRESSURE HAS FORMED OVER SOUTHERN SASKATCHEWAN WITH A WARM
FRONT EXTENDING SOUTHEAST TO BISMARCK NORTH DAKOTA.
TONIGHT AND SATURDAY...MODELS ARE IN GOOD AGREEMENT DROPPING THE
SHORTWAVE TROUGH OVER ALBERTA THROUGH THE NORTHERN PLAINS AND INTO
NEBRASKA BY 00Z SUNDAY. THIS TROUGH HELPS TO EJECT AND SHEAR OUT THE
NEW MEXICO UPPER LOW...WHICH GETS LIFTED INTO SOUTHERN ILLINOIS AND
INDIANA. THE TRACKS OF THESE FEATURES SPLIT THE FORECAST AREA...
HOWEVER...THERE ARE STILL CONCERNS. THE MAIN ONE IS WITH LOW LEVEL
SATURATION. 925-900MB RH PROGS FROM THE 04.12Z NAM/GFS SHOW THAT AS
THE NEW MEXICO UPPER LOW LIFTS NORTHEAST...AN AREA OF LOW STRATUS
FORMS ACROSS MISSOURI SATURDAY MORNING...WHICH THEN SPREADS INTO
EASTERN IOWA AND SOUTHERN WISCONSIN DURING THE AFTERNOON. ABOVE
900MB...TROPOSPHERE IS STILL PRETTY DRY. ANALYSIS LOOKING AT THE
275-280K SURFACES SHOWS THAT MOISTURE GETS PULLED UP OUT OF THE GULF
OF MEXICO AS THE NEW MEXICO UPPER LOW LIFTS NORTHEAST. IN
ADDITION...THERE IS WEAK LIFT ON THESE SURFACES...WHICH GIVEN THAT
THE TEMPERATURE PROFILE HAS NO ICE...COULD LEAD TO FREEZING DRIZZLE
FORMATION. AS SUCH...HAVE RETAINED A MENTION OF FREEZING DRIZZLE
FROM 21-00Z...BUT RESTRICTED IT TO THE SOUTHEAST 1/3 OF THE AREA TO
CORRELATE WITH THE LIFT ON THE 275-280K SURFACES. ELSEWHERE...DRY
CONDITIONS WILL PREVAIL WITH PERHAPS LITTLE IN THE WAY OF CLOUD
COVER UNTIL LATER SATURDAY. WITH CLEAR SKIES AND DRY AIR TONIGHT...
ALONG WITH LIGHT WINDS IN MOST LOCATIONS EXCEPT FOR SOUTHEAST
MINNESOTA...TEMPERATURES COULD REALLY TANK TONIGHT. WENT SLIGHTLY
BELOW GUIDANCE FOR THE TYPICAL COLD SPOTS AS THINK THEY SHOULD BE
ABLE TO COME CLOSE TO ZERO. SINGLE DIGITS LOOK LIKELY ELSEWHERE.
925MB TEMPS ARE FAIRLY SIMILAR TO TODAY FOR SATURDAY...AND WITH
PLENTY OF SUN...HIGHS SHOULD TOP OUT CLOSE TO THOSE TODAY.
SATURDAY NIGHT AND SUNDAY...MODELS SHOW ANOTHER SHORTWAVE COMING OUT
OF SOUTH CENTRAL CANADA LATE SATURDAY...DROPPING SOUTHEAST INTO
WESTERN ILLINOIS BY 18Z SUNDAY. THIS SHORTWAVE WILL HELP TO KICK THE
TROUGH DROPPING INTO NEBRASKA EASTWARD...BUT ALSO BRING WITH IT A
SURGE OF DRY...COLDER AIR. BY 18Z SUNDAY...925MB TEMPS OVER THE
FORECAST AREA ARE AROUND -8C. PRIOR TO THE COLD AIR ARRIVAL...THERE
IS A CONCERN TO DEAL WITH WHICH IS THE SAME AS SATURDAY...LOW
STRATUS AND ANY LIGHT PRECIPITATION POSSIBLE WITH IT. IN THIS
CASE...MODELS HAVE AN AREA OF STRATUS COMING INTO THE FORECAST AREA
BEHIND A COLD FRONT ASSOCIATED WITH THE NEBRASKA TROUGH. VERY LITTLE
IF ANY ISENTROPIC LIFT IS NOTED WITHIN THIS STRATUS...SO THINK ANY
LIGHT PRECIPITATION POTENTIAL WOULD REMAIN OVER THE SOUTHEAST THIRD
OF THE AREA EARLY IN THE EVENING AHEAD OF THE FRONT. AGAIN...THIS IS
LIKELY TO BE FREEZING DRIZZLE GIVEN LACK OF ICE IN THE CLOUD. AFTER
MIDNIGHT...THERE ARE INDICATIONS OF A SECONDARY TROUGH WHICH IN
925MB TEMPS ALMOST LOOKS LIKE A WARM FRONT DROPPING SOUTH THROUGH
WISCONSIN. 270-275K ISENTROPIC LIFT PLOTS SHOW SOME LOW LEVEL LIFT
WITH THIS...LIKELY ENOUGH TO PRODUCE LIGHT PRECIPITATION. IT APPEARS
ICE WILL EXIST IN THE CLOUD THIS TIME...AIDED TOO BY MID CLOUDS
DROPPING SOUTH WITH THE SHORTWAVE COMING OUT OF SOUTH CENTRAL
CANADA. THUS...HAVE MAINTAINED A FLURRY MENTION. DRYING AND CLEARING
WILL TAKE PLACE SUNDAY MORNING FROM NORTHWEST TO SOUTHEAST. THE
INCREASE OF CLOUDS AND COLD ADVECTION WILL COUNTER-ACT EACH OTHER
SATURDAY NIGHT FOR LOWS...AND HAVE WENT WITH A BLEND OF GUIDANCE
SUGGESTING TEMPERATURES DROPPING INTO THE TEENS. SLIGHTLY COLDER DAY
EXPECTED ON SUNDAY GIVEN THE AFOREMENTIONED 925MB TEMPS.
SUNDAY NIGHT AND MONDAY...ATTENTION TURNS TO DEEP TROUGHING JUST OFF
THE WEST COAST OF NORTH AMERICA. OTHER THAN THE 04.12Z NAM...ALL
OTHER MODELS DEPICT THE TROUGH PROGRESSING EASTWARD INTO THE WESTERN
U.S. THROUGH THE WEEKEND AND SPLITTING INTO TWO. THE SOUTHERN
PART FORMS INTO A CUT-OFF LOW WHICH GETS STUCK IN THE SOUTHWESTERN
U.S.. THE NORTHERN PART IS A TROUGH THAT TRACKS ALONG THE
U.S./CANADIAN BORDER...BRINGING WITH IT A DYING COLD FRONT INTO
WESTERN MINNESOTA ON MONDAY. REGARDING THAT 04.12Z NAM...THE MODEL
HAS BEEN DISCOUNTED AS AN OUTLIER AS IT KEEPS A FULL SCALE TROUGH
AND MARCHES IT EASTWARD INTO THE PLAINS BY 00Z TUESDAY. NO MATTER
WHAT MODEL SOLUTION IS FOLLOWED...THIS PERIOD ENDS UP DRY WITH WARM
ADVECTION THROUGHOUT AS LOW LEVEL SOUTHWEST WINDS INCREASE AHEAD OF
THE APPROACHING SPLIT TROUGH AND DYING SURFACE COLD FRONT. 925MB
TEMPS CLIMB TO -2 TO -4C BY 18Z MONDAY WHILE 850MB TEMPS JUMP TO +2
TO +4C. THUS...MONDAY SHOULD END UP MUCH WARMER THAN SUNDAY WITH
MOST LOCATIONS TOPPING OUT FROM THE UPPER 20S TO MID 30S PER ECMWF
GUIDANCE. COLDEST LOCATIONS EXPECTED OVER SOUTHEAST MINNESOTA AND
NORTHEAST IOWA WITH HIGHER ALBEDO FROM SNOWPACK. LOWS SUNDAY NIGHT
LIKELY IN THE EVENING BEFORE SOUTHWEST WINDS PICK UP. FOLLOWED BLEND
OF GUIDANCE FOR LOWS.
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY
233 PM CST FRI JAN 4 2013
FOCUS AS HAS BEEN THE PAST FEW DAYS IS ON THE UPPER LOW IN THE
SOUTHWESTERN U.S. ON MONDAY. YET AGAIN THERE IS A SPLIT IN SCENARIOS
AMONGST MODEL HANDLING OF THIS UPPER LOW:
1. THE 04.12Z CANADIAN REPRESENTS A VERY FAST SCENARIO...LIFTING IT
NORTHEAST ACROSS CHICAGO TUESDAY NIGHT. WE WOULD END UP WITH A LIGHT
TO MODERATE SNOWFALL ACROSS THE FORECAST AREA TUESDAY INTO TUESDAY
NIGHT SHOULD THIS VERIFY.
2. NEXT BEHIND THE CANADIAN IS THE 04.12Z GFS...LIFTING IT FROM
TEXAS ON TUESDAY INTO THE OHIO VALLEY ON WEDNESDAY. THIS SCENARIO
WOULD IT PAN OUT WOULD KEEP THE AREA DRY AND TEMPERATURES ABOVE
NORMAL THROUGH THURSDAY.
3. LASTLY...THE 04.12Z ECMWF/UKMET ARE EXTREMELY CONSISTENT WITH
PAST ECMWF RUNS...HAVING THE UPPER LOW CROSS NORTHERN MEXICO ON
TUESDAY...SHIFTING INTO TEXAS ON WEDNESDAY...THEN LIFTING INTO
ILLINOIS ON THURSDAY. THIS SCENARIO WOULD YIELD ABOVE NORMAL
TEMPERATURES THROUGH THURSDAY...WITH DRY WEATHER THROUGH WEDNESDAY
EVENING...RAIN TO MUCH OF THE AREA FOR LATE WEDNESDAY NIGHT INTO
THURSDAY...THEN TAPERING OFF TO A SNOW OR RAIN/SNOW MIX THURSDAY
NIGHT.
THE WHOLE PROBLEM RESULTING IN THE VARIOUS SCENARIOS STARTS ON
SUNDAY...REGARDING HOW QUICK THE DEEP UPPER TROUGH SPLITS INTO TWO
AND HOW FAST UPPER RIDGING CAN BUILD INTO THE PACIFIC NORTHWEST
BEHIND IT. PER HPC AND WANTING TO FOLLOW THE CONSISTENT AND GOOD
EXTENDED VERIFYING ECMWF...LEANED THE LONG TERM FORECAST MORE
TOWARDS THE ECMWF SOLUTION. THIS ALSO IS IN BETTER AGREEMENT WITH
THE PREVIOUS FORECAST. STILL HAVE ENDED UP KEEPING A SNOW OR
RAIN/SNOW MIX IN FOR WEDNESDAY NIGHT INTO THURSDAY MORNING...TO
HANDLE UNCERTAINTY ON THE TEMPERATURE RISE AND NOT WANTING TO
INTRODUCE FREEZING RAIN SINCE THAT TYPE SEEMS UNLIKELY.
AFTER THURSDAY...NEW DEEP TROUGHING IS FORECAST TO FORM BY ALL
MODELS OVER THE WESTERN U.S....WHICH IS ONE OF THE FEATURES THAT
HELPS KICK OUT THE UPPER LOW IN THE ECMWF/UKMET. SHORTWAVES EJECTING
OUT OF THE TROUGH REQUIRE CHANCES OF SNOW IN FOR FRIDAY. COOLER
TEMPERATURES ARE LIKELY AS WELL...THOUGH AT LEAST FOR FRIDAY STILL
CLOSE TO NORMAL AS THE DEEPER COLDER AIR ASSOCIATED WITH THE TROUGH
HOLDS OFF UNTIL THE WEEKEND.
&&
.AVIATION...TODAY AND SATURDAY
1138 AM CST FRI JAN 4 2013
VFR CONDITIONS WILL DOMINATE MOST OF THIS FORECAST. SPLIT UPPER FLOW
REGIMES BRING SOME UNCERTAINTY ON HOW IMPULSES IN BOTH FLOWS WILL
COME TOGETHER THIS WEEKEND. WHILE CLEAR/VFR CONDITIONS EXPECTED TO
PREVAIL INTO SATURDAY AFTERNOON...COULD SEE SOME LOWER CEILINGS
APPROACH FROM THE SOUTHWEST IN SOUTHERN BRANCH OF FLOW BUT THESE
MVFR CEILINGS WOULD MAINLY IMPACT AREAS ACROSS EASTERN IOWA INTO
SOUTHERN WISCONSIN. COULD ALSO SEE SOME MVFR CEILINGS BRUSH THROUGH
PARTS OF NORTH CENTRAL WISCONSIN OVERNIGHT IN NORTHWEST FLOW.
NONE OF THIS EXPECTED TO IMPACT TAF SITES THROUGH 18Z SATURDAY BUT
COULD SEE SOME SATURATION HEADING INTO SATURDAY EVENING WITH STRETCH
OF LOWER CEILINGS DEVELOPING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
233 PM CST FRI JAN 4 2013
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....SHEA
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
921 PM PST SAT JAN 5 2013
.SHORT TERM DISCUSSION...
SATELLITE IMAGERY SHOWED A ELONGATED SPLITTING TROUGH ALIGNED ALONG
THE PACIFIC COASTLINE FROM THE GULF OF ALASKA TO SAN FRANCISCO EARLIER
THIS EVENING. LATEST WATER VAPOR LOOP SHOWS THAT ENERGY ROUNDING THE
BASE OF THIS TROUGH HAS BEGUN TO DECOUPLE FROM THE MEAN WESTERLY JET
AND IS SHOWING SIGNS THAT IT IS FORMING A 550MB CLOSED LOW LESS THAN
A HUNDRED MILES OFFSHORE OF THE BAY AREA.
THE BROAD TRANSITIONAL NATURE OF THIS SYSTEM LEAD TO RELATIVELY
WEAK DIFFERENTIAL FORCING/ISENTROPIC LIFT THUS FAR. THE RESULT OF
THIS IS A WIDESPREAD ALBEIT LIGHT PRECIPITATION EVENT. THIS IS
EVIDENT BY AREAL RAIN GAGES REPORTING LESS THAN A TENTH OF RAIN
WITH ONLY A SELECT FEW BREACHING THE QUARTER INCH MARK THIS
EVENING. RADAR IMAGERY SHOWS WIDESPREAD LOW REFLECTIVITIES
INDICATIVE OF LIGHT PRECIPITATION WITH THE EXCEPTION OF AN AREA OF
HEAVIER RAIN/GRAUPEL ON THE WESTERN PERIPHERY OF THE CENTRAL SAC
VALLEY. KRDD STRUGGLING TO SECURE A TRACE OF RAIN SO FAR.
THE UPPER LEVEL SYSTEMS ARRIVAL HAS HASTENED SINCE THE LAST SHORT
TERM MODELS WERE INITIALIZED. THE SREF...NAM...AND HRRR MODELS ARE
ALL LAGGING REALITY BY ABOUT 3 HOURS PER LATEST RADAR IMAGERY.
DESPITE THIS... WOULD AGREE WITH THE SHORT TERM MODELS SCALING
BACK PRECIP OVER THE NORTHERN SAC VALLEY/SOUTHERN CASCADES TONIGHT
AND TOMORROW MORNING. DECIDED TO SCALE BACK PRECIP
COVERAGE AND PROBABILITY OVER THE NEXT 72 HRS AND SENT OUT A
FORECAST UPDATE.
SNOW LEVELS OVER THE COASTAL RANGE ARE DROPPING AS A RESULT OF
COLD POST FROPA AIR MOVING INTO THE REGION. INITIALLY ABOVE
4500FT... WEBCAMS HAVE SHOWN THE SNOW LEVEL TO BE BETWEEN 2500FT
AND 3000FT IN LAKE COUNTY. EXPECT A FURTHER DROP OVERNIGHT.
REMAINDER OF AFTERNOON FORECAST PACKAGE ON TRACK.
.PREVIOUS DISCUSSION...
UPPER LOW APPROACHING THE WEST COAST WILL DISPLACE THE HIGH THAT
HAS BEEN OVER THE AREA THE PAST FEW DAYS. ENERGY DROPPING THROUGH
THE TROUGH WILL CAUSE AN UPPER LOW TO SPLIT FROM THE TROUGH NEAR
THE BAY AREA TONIGHT. RAIN WILL SPREAD INTO THE VALLEY THIS
EVENING...AFTER 6 PM FOR MOST AREAS. SNOW LEVELS WILL START OUT
NEAR 5000 FEET OVER THE SIERRA AND 3000 FEET FOR THE COASTAL RANGE
AND SHASTA COUNTY. LEVELS WILL FALL TO 4000 FEET FOR THE SIERRA
AND 2500 FEET FARTHER NORTH SUNDAY MORNING. SNOWFALL WILL BE LIGHT
WITH THIS SYSTEM...AS THE BEST MOISTURE AND DYNAMICS WILL BE OVER
THE SOUTHERN SIERRA AND SOCAL. EXPECT 2 TO 4 INCHES OVER THE
COASTAL RANGE AND SIERRA DURING THE NEXT 24 HRS. HAVE RAISED
OVERNIGHT POPS AND ALSO ADJUSTED FOR EARLIER TIMING...AS SYSTEM IS
A FEW HOURS AHEAD OF SCHEDULE. THIS LINES UP NICELY WITH RUC/HRRR
WHICH BEGIN PRECIP OVER THE COASTAL RANGE AROUND 4 PM AND SAC/SAN
JOAQUIN VALLEY AROUND 6 PM. PRECIP WILL BE SLOWER TO SPREAD INTO
THE SIERRA WHERE A DRIER ATMOSPHERE EXIST...ACCUMULATING SNOW
THERE WILL NOT START UNTIL AFTER MIDNIGHT.
UPPER LOW WILL DROP SOUTH OVER SOCAL ON SUNDAY. PRECIP WILL
DIMINISH FROM NORTHWEST TO SOUTHEAST DURING THE DAY.
ALTHOUGH...STILL REMAIN IN THE LIKELY CATEGORY OVER THE SIERRA
SOUTH OF I-80. FOG COULD BE A CONCERN SUNDAY NIGHT IF SKIES
CLEAR...BUT AT THIS TIME WILL KEEP THE CLOUDS OVER THE AREA.
DISTURBANCE AND MOISTURE PLUME OVER WASHINGTON AND OREGON ON
MONDAY WILL BRUSH NORTHERN AREAS AND WILL KEEP SHOWER CHANCES
GOING FOR SHASTA COUNTY AND THE COASTAL RANGE. HEIGHT RISES AHEAD
OF THIS SYSTEM WILL LEAD TO WARMER TEMPERATURES WITH HIGHS
GENERALLY FROM 55 TO 60. RIDGE WILL STRENGTHEN OVER NORCAL ON
TUESDAY PUSHING SHOWER CHANCES NORTH OF THE AREA. TEMPERATURES
WILL BE FROM THE MID 50`S TO LOWERS 60`S FOR VALLEYS.
.EXTENDED DISCUSSION (WEDNESDAY THROUGH SATURDAY)
SLIGHT CHANCE TO CHANCE OF PRECIP ACROSS NORCAL WED & THURS AS A
TROUGH OVER THE PAC NW DEEPENS INTO OUR REGION. SNOW LEVELS COULD
LOWER INTO THE FOOTHILLS ALTHOUGH MODELS INDICATE THAT ANY
SNOWFALL WOULD BE LIGHT AT THE LOWER ELEVATIONS. THE TROUGH AXIS
MOVES INTO THE GREAT BASIN REGION BY FRIDAY AND BREEZY NORTH TO
NORTHEAST FLOW WILL DEVELOP IN OUR CWA BEHIND THE TROUGH. FRIDAY
AND SATURDAY WILL BE DRIER WITH THE NORTHERLY FLOW BUT SOME LIGHT
SHOWERS MAY STILL AFFECT THE NORTHERN MOUNTAINS AND SHASTA COUNTY.
OVERNIGHT LOWS WILL BE BELOW NORMAL WITH DAYTIME HIGHS AT OR
SLIGHTLY BELOW NORMAL. IT SHOULD BE NOTED THAT THE ECMWF MODEL IS
A BIT OF AN OUTLIER IN THE EXTENDED AS IT DIFFERS FROM THE GEM &
GFS (THE PATTERN MENTIONED ABOVE) IN TRACK AND TIMING. JBB
&&
.AVIATION...
VFR/MVFR CONDITIONS AND AREAS OF IFR/LIFR CONDITIONS IN THE VALLEY WITH
AN UPPER LEVEL LOW MOVING INTO THE AREA TONIGHT BRINGING SHOWERS.
IFR/LIFR CONDITIONS EXPECTED IN THE MOUNTAINS OVERNIGHT INTO SUNDAY
WITH SNOW LEVELS AROUND 3000 TO 4000 FT. SWLY WIND GUSTS UP TO 40
KTS NEAR SIERRA RIDGES. PRECIPITATION EXPECTED TO DIMINISH FROM
NORTH TO SOUTH SUNDAY AFTERNOON AND EVENING.
&&
.STO WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1004 PM MST SAT JAN 5 2013
.AVIATION...
VFR CONDITIONS ARE EXPECTED TO CONTINUE OVER THE KCOS AND KPUB TAF
SITES THROUGH SUNDAY. AT ALS...THE POTENTIAL FOR LIFR CONDITIONS IS
STILL ANTICIPATED AT TIMES LATER TONIGHT DUE TO CIGS AND VIS
ASSOCIATED WITH FZFG...THEN VFR CONDITIONS SHOULD RETURN TO
KALS...ESPECIALLY AFT 16Z SUNDAY.
&&
.PREV DISCUSSION... /ISSUED 249 PM MST SAT JAN 5 2013/
SHORT TERM...
(TONIGHT AND SUNDAY)
SHORTWAVE PASSING OFF TO THE NORTHEAST HAS SENT A DRY COLD FRONT
THROUGH THE SE PLAINS. WINDS NOT TERRIBLY STRONG WITH IT...AND
MIXING HAS ACTUALLY WARMED TEMPS A FEW DEGREES IN SPITE OF THE CAA
BEHIND THE FRONT...WITH KLAA AT 45 DEGREES SO FAR...COMPARED TO
YESTERDAY`S HIGH OF ONLY 39. MEANWHILE...THE SAN LUIS VALLEY HAS
BEEN STRUGGLING TO WARM...WITH KALS ONLY AT 11 DEGREES AS OF 21Z.
TONIGHT...CLEAR SKIES...DRY SFC DEW POINTS...AND SNOW COVER IN SOME
PLACES WILL LEAD TO ANOTHER COLD NIGHT. CAN`T FIND A REASON WHY
KALS WON`T DROP TO AROUND -30 AGAIN TONIGHT...SO TOOK MIN TEMPS
THERE WELL BELOW GUIDANCE. OTHER CHALLENGE WILL BE POTENTIAL FOR
FOG IN THE SAN LUIS VALLEY. THIS DIDN`T HAPPEN LAST NIGHT...OR AT
LEAST VISIBILITY AT KALS DIDN`T DROP BELOW 5 MILES...THOUGH WE DID
SEE SOME LIFR STRATUS IN THE WEB CAMS AND IN THE CEILOMETER DATA FROM
ASOS. NAM12 SOUNDINGS SATURATE AT THE SFC AROUND 02Z AND REMAIN SO
THROUGH 15Z SUN. THE LOCAL 4 KM WRF ALSO INDICATES POTENTIAL FOR
FOG...AND HRRR SHOWS SFC RHS APPROACHING 80% BY 09Z SUN. RAP
SOUNDINGS BY CONTRAST LOOK FAIRLY DRY...AND NEITHER THE MET NOR MAV
GUIDANCE HAVE ANY INDICATION OF FOG. WILL THROW PATCHY FOG INTO THE
GRIDS FOR NOW...BUT WILL DELAY THIS UNTIL AFTER 06Z. HUNCH IS IT
WON`T OCCUR UNTIL AFTER 09-10Z BASED ON WHAT HAPPENED LAST
NIGHT...AND SHOULD BREAK BY 15-16Z ON SUN.
FLOW ALOFT BECOMES MORE SOUTHWESTERLY ON SUNDAY AS THE UPPER RIDGE
SHIFTS EASTWARD AND NEXT UPPER LOW MOVES INTO CA. LEE TROF
DEEPENS IN RESPONSE WITH WINDS AIDING IN BETTER MIXING ALONG THE
I-25 CORRIDOR. CURRENT FORECAST WITH 40S AND LOWER 50S LOOK
REASONABLE ACROSS THE PLAINS. MEANWHILE...DRY CONDITIONS WILL
CONTINUE EVERYWHERE. ITS POSSIBLE THAT KALS COULD SEE SOME
MODERATING TEMPERATURES AS WELL IF WINDS CAN MIX IN...BUT GIVEN THE
STRONG INVERSIONS...KEPT TEMPS BELOW GUIDANCE VALUES WITH SOME MINOR
IMPROVEMENT. -KT
LONG TERM...
(SUNDAY NIGHT-SATURDAY)
SUNDAY NIGHT-MONDAY...LATEST MODELS CONTINUE TO BE IN GOOD AGREEMENT
OF DEVELOPING SPLIT FLOW PATTERN INTO THE MIDDLE WEEK. CLOSED LOW IN
THE DEVELOPING SOUTHERN STREAM ACROSS THE SOUTHEASTERN NEVADA SUNDAY
AFTERNOON PROGGED TO DIVE INTO OLD MEXICO THROUGH THE DAY MONDAY AS
A MINOR WAVE EMBEDDED IN THE ZONAL FLOW ACROSS NORTHERN TIER OF
STATES TRANSLATES ACROSS THE NORTHERN ROCKIES AND INTO THE NORTHERN
HIGH PLAINS. OVERNIGHT LOWS...ESPECIALLY IN THE SAN LUIS VALLEY
REMAIN TRICKY WITH SOME INCREASE IN HIGH LEVEL MOISTURE SPREADING
ACROSS THE REGION...THOUGH DOES NOT LOOK TO BE ENOUGH TO KEEP TEMPS
FROM TANKING...AND HAVE GONE BELOW GUIDANCE VALUES IN THE HIGH MT
VALLEYS. BOTH SYSTEMS REMAIN TOO FAR AWAY FROM THE AREA TO PRODUCE
ANY PRECIPITATION...THOUGH WILL SEE SLIGHTLY COOLER TEMPERATURES
AS PASSING NORTHERN STREAM SYSTEM SENDS A WEAK BACKDOOR COLD FRONT
ACROSS EASTERN COLORADO MONDAY MORNING.
MONDAY NIGHT-WEDNESDAY NIGHT...WEAK FLOW PROGGED ACROSS THE AREA
THROUGH THIS PERIOD AS OLD MEXICO LOW SLOWLY LIFTS OUT INTO THE
SOUTHERN HIGH PLAINS. MODELS DIFFER ON TRACK WITH THE EC A TAD
FURTHER NORTH AND WEST WITH SAID SYSTEM ACROSS THE NORTH CENTRAL
TEXAS PANHANDLE WEDNESDAY NIGHT AND PRINTS OUT SOME LIGHT QPF
ACROSS THE FAR SE PLAINS. WITH THE WEAK FLOW ALOFT...HAVE GONE BELOW
GUIDANCE FOR HIGHS THROUGH THE PERIOD...WITH TEMPERATURES MAINLY IN
THE 40S TO LOWER 50S ACROSS THE PLAINS AND 30S ACROSS THE HIGHER
TERRAIN. AGAIN...HAVE STAYED WELL BELOW GUIDANCE FOR THE SAN LUIS
VALLEY AS NOT ENOUGH WIND TO SCOUR OUT THE COLD AIRMASS IN PLACE.
THURSDAY-SATURDAY...LATEST MODELS CONTINUE TO INDICATE A BETTER
CHANCE OF WIDESPREAD PRECIPITATION INTO THE EARLY WEEKEND AS PACIFIC
ENERGY DIGGING INTO THE GREAT BASIN ON THURSDAY SLOWLY LIFTS OUT
ACROSS THE ROCKIES THROUGH SATURDAY. SOME CONCERN THAT STRONG
BACKSIDE JET ACROSS THE GREAT BASIN COULD DIG THE SYSTEM FURTHER
SOUTH THAN CURRENT PROJECTIONS...SO HAVE KEPT CURRENT MODEL
CONSENSUS SOLUTION WHICH GIVES CHANCE POPS ACROSS THE CONTINENTAL
DIVIDE THURSDAY NIGHT AND FRIDAY...WITH CHANCE AND SLIGHT CHANCE
POPS SPREADING ACROSS THE REST OF THE HIGHER TERRAIN THROUGH THE
EASTERN PLAINS FRIDAY THROUGH SATURDAY. TEMPERATURES WILL ALSO BE
TRENDING BACK BELOW SEASONAL AVERAGES BY FRIDAY AND SATURDAY. -MW
AVIATION...
CLEAR SKIES AND VFR CONDITIONS EXPECTED AT KPUB AND KCOS THROUGH
SUNDAY. CHALLENGE WILL BE THE POTENTIAL FOR LIFR CIGS AND POSSIBLY
VIS IN FZFG AT KALS OVERNIGHT. MODELS DIFFER IN WHETHER THIS WILL
OR WILL NOT OCCUR...AND CONFIDENCE IS LOW. PLAN TO DELAY LIFR
CONDITIONS UNTIL AFTER 09Z IN NEXT TAF ISSUANCE. ANY LIFR CIGS/VIS
SHOULD BREAK BETWEEN 15-16Z...WITH VFR CONDITIONS AND LIGHT WINDS
THROUGH SUNDAY. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS ALBANY NY
1230 AM EST SUN JAN 6 2013
.SYNOPSIS...
HIGH PRESSURE OVER THE REGION THIS EVENING...WILL SLIDE OFF THE
ATLANTIC SEABOARD LATER TONIGHT. LOW PRESSURE AND ITS ASSOCIATED
COLD FRONT TRACKING EAST FROM THE GREAT LAKES WILL MOVE THROUGH OUR
REGION LATE TONIGHT THROUGH SUNDAY NIGHT. THIS COULD BRING PERIODS
OF LIGHT SNOW OR SNOW SHOWERS...WITH THE BEST CHANCE FOR
ACCUMULATIONS IN THE HIGHER TERRAIN. DRIER AND MILDER WEATHER IS
EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH SUNDAY NIGHT/...
AS OF MIDNIGHT...REGIONAL RADAR RETURNS REVEAL AN INCREASING TREND
OF PRECIPITATION EVOLVING AS WEAK WARM ADVECTION AND ISENTROPIC LIFT
IS UNDERWAY. HRRR EXPERIMENTAL REFLECTIVITIES SUGGEST THIS BAND OF
LIGHT SNOW/-SHSN WILL OVERSPREAD THE ENTIRE REGION BY 09Z AND HAVE
INCREASED POPS TO 30% FOR THE OVERNIGHT PERIOD. THERE IS A NOTABLE
DRY SLOT UPSTREAM OVER THE OHIO VALLEY THAT WILL ADVANCE NORTHEAST
TOWARD SUNRISE. THIS SHOULD REDUCE COVERAGE OF PRECIP THROUGH MOST
OF THE DAYLIGHT HOURS ON SUNDAY WITH PERHAPS FLURRIES FOR MOST
LOCATIONS. THE LAKE ONTARIO CONTRIBUTION DOES NOT APPEAR TO BE
OCCURRING ON SUNDAY AS PREVIOUSLY THOUGHT AND MAY HAVE TO REDUCE
ACCUMULATIONS WITH THE NEXT UPDATE. AS FOR TEMPERATURES...WE HAVE
NOW STEADY THOSE VALUES WITH A SLOWLY RISE EXPECTED THE REMAINDER OF
THE OVERNIGHT PERIOD WHICH WILL CONTINUE INTO SUNDAY AFTERNOON.
COLD FRONT AND UPPER TROUGH IS STILL SCHEDULED TO MOVE ACROSS THE
REGION TONIGHT...WITH TRENDS TOWARD A FASTER AND A SOMEWHAT DRIER
SOLUTION. NOT SO DOWNWIND OF LAKE ONTARIO WHERE SOME LAKE
CONTRIBUTION COULD ALLOW FOR A BETTER CONCENTRATION FOR SNOW. MORE
ON THIS WITH THE NEXT UPDATE.
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
THE CLIPPER SYSTEM WILL PASS ACROSS FAR NORTHERN NEW YORK AND
NORTHERN NEW ENGLAND SUNDAY INTO SUNDAY NIGHT. AS IS USUALLY THE
CASE WITH THESE CLIPPER SYSTEMS...EXPECT MOST OF THE SIGNIFICANT
SNOWFALL ASSOCIATED WITH IT TO REMAIN ALONG OR TO THE NORTH OF THE
SURFACE LOW TRACK. THIS WILL RESULT IN VERY LITTLE PCPN FOR MOST OF
THE ALBANY FORECAST AREA WITH THE EXCEPTION OF THE ADIRONDACK
ZONES. FOR MUCH OF HAMILTON AND NORTHERN HERKIMER COUNTIES...LIKELY
POPS ARE FORECAST SUNDAY INTO SUNDAY NIGHT...WITH CHANCE TO SLIGHT
CHANCE POPS ELSEWHERE. SNOWFALL AMOUNTS MAY REACH 4 TO 5 INCHES WITH
THIS EVENT ACROSS PARTS OF THE ADIRONDACKS...BUT IT WILL BE SPREAD
OUT OVER 24 TO 36 HOURS SO HAVE NOT ISSUED ANY ADVISORIES AT THIS
TIME...AND NEITHER HAVE ANY OF THE SURROUNDING OFFICES.
AFTER THE LOW MOVES TO THE EAST...A LARGE HIGH PRESSURE SYSTEM WILL
TAKER CONTROL OF OUR WEATHER FOR MONDAY AND MONDAY NIGHT. THIS WILL
NOT BE A VERY COLD AIRMASS SO TEMPS WILL BE NEAR OR ABOVE NORMAL
DURING THAT TIME.
FOR TEMPS...HIGHS SUNDAY WILL BE IN THE 30S. LOWS SUNDAY NIGHT IN
THE TEENS TO MID 20S. HIGHS MONDAY IN THE 20S TO MID 30S...AND LOWS
MONDAY NIGHT IN THE UPPER SINGLE NUMBERS AND TEENS AS CLEAR SKIES
AND LIGHT WINDS ALLOW FOR GOOD RADIATIONAL COOLING.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
HIGH PRESSURE WILL DOMINATE MUCH OF THE LONG TERM PERIOD BEFORE A
POTENTIAL STORM SYSTEM APPROACHES LATE NEXT WEEK.
HIGH PRESSURE WILL BE SITUATED OVER THE EASTERN THIRD OF THE CONUS
AS A DEEP UPPER-LEVEL TROUGH DEVELOPS OVER THE WEST COAST TO START
THE LONG TERM PERIOD. THIS AREA OF HIGH PRESSURE WILL BEGIN TO SLIDE
OFF THE EASTERN SEABOARD TUESDAY...ALLOWING A MILD
WEST-SOUTHWESTERLY RETURN FLOW TO DEVELOP ACROSS THE AREA.
TEMPERATURES LOOK TO REBOUND NICELY FROM THE ARCTIC AIRMASS THAT
PRODUCED THE COLD TEMPERATURES DURING THE PREVIOUS WEEK.
EXPECT THE TUESDAY-THURSDAY MORNING TIMEFRAME TO BE DRY FOR MOST OF
THE FORECAST AREA...HOWEVER MENTIONED SLIGHT CHANCE POPS FOR
NORTHERN AREAS AS THE 12Z GFS/ECMWF DEPICT A WEAK SHORTWAVE DIPPING
SOUTH OUT OF THE NORTHERN STREAM FLOW THAT COULD SPAWN A FEW SNOW
SHOWERS IN THE SOUTHERN ADIRONDACKS.
A STORM SYSTEM WILL EJECT OUT OF THE PLAINS AND MIDWEST DURING
MIDWEEK...HOWEVER THERE ARE STILL SIGNIFICANT TIMING AND QPF
DIFFERENCES AMONGST THE GUIDANCE...USED A BLENDED APPROACH TO
ACCOUNT FOR THESE DIFFERENCES. REGARDLESS...HAVE CHANCE POPS FOR THE
THURSDAY NIGHT-FRIDAY MORNING TIMEFRAME AS GUIDANCE IS HONING IN ON
THIS TIMEFRAME BEING ASSOCIATED WITH THE FRONTAL PASSAGE. CURRENT
THERMAL PROFILES MAINLY SUGGEST A RAIN EVENT...ALTHOUGH THERE COULD
BE A MIX OF RAIN AND SNOW TOWARDS DAYBREAK FRIDAY MORNING.
TEMPERATURES ARE EXPECTED TO BE ABOVE AVERAGE DURING THE LONG TERM
PERIOD WITH HIGHS GENERALLY IN THE LOW TO MID 40S IN VALLEY REGIONS
AND MID TO UPPER 30S IN THE HIGHER TERRAIN BEGINNING WEDNESDAY AND
LASTING THROUGH THE REMAINDER OF THE LONG TERM PERIOD. LOWS WILL
GENERALLY BE IN THE MID 20S IN THE HIGHER TERRAIN TO LOW 30S IN
VALLEY LOCATIONS.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
WEAK WARM ADVECTION ASSOCIATED WITH AN APPROACHING FRONTAL
SYSTEM/UPPER LEVEL SHORTWAVE WILL ALLOW MID LEVEL CLOUDS TO CONTINUE
TO THICKEN AND LOWER FOR THE REMAINDER OF THE NIGHT. UPSTREAM RADARS
SHOWS SOME LIGHT SNOW SHOWERS/FLURRIES...BUT MUCH OF THIS ACTIVITY
LOOKS TO HAVE A DIFFICULT TIME MAKING ITS WAY TO THE SURFACE THANKS
TO THE DRY AIR IN PLACE AT LOW LEVELS. HIRES MESOSCALE MODELS
SUGGEST THESE SNOW SHOWERS MAY AFFECT OUR AREA BETWEEN 08Z-12Z...SO
WILL INCLUDE A VCSH DURING THIS TIME PERIOD. HAVE ALSO INCLUDED A
TEMPO FOR MVFR VSBYS IN CASE A BRIEF PERIOD OF LOWER VSBYS OCCUR
WITHIN ANY SNOW SHOWER...BUT IFR CONDITIONS ARE NOT ANTICIPATED AT
THIS TIME. CIGS SHOULD LOWER TO ABOUT 4-6 KFT TOWARDS THE END OF THE
NIGHT WITH THE PASSING WARM FRONT. WINDS FOR THE REMAINDER OF THE
LIGHT WITH BE SOUTHERLY AND VERY LIGHT /5 KTS OR LESS/ OR CALM.
THE BEST WARM AIR ADVECTION WILL SHIFT EAST OF THE REGION FOR DURING
THE DAY SUNDAY...PUTTING OUR AREA IN A LULL FOR PRECIPITATION. AS A
RESULT...WILL NOT MENTION A VCSH DURING THE DAY SUNDAY WITH JUST
SOME LINGERING BKN LOW AND MID LEVEL CLOUDS AND CONTINUED VFR
CONDITIONS. SOUTHERLY AREAS...SUCH AS AROUND KPOU...MAY HAVE CLOUDS
SCT OUT FOR THE AFTN HOURS. LIGHT SW WINDS OF 7 KTS OR LESS WILL BE
IN PLACE THROUGHOUT THE AREA.
THE STORM/S COLD FRONT LOOKS TO APPROACH THE AREA FOR SUNDAY
EVENING/OVERNIGHT...SO WILL HAVE BKN-OVC CIGS OF 4-7 KFT AND INCLUDE
A MENTION OF VCSH...ALTHOUGH THE BEST CHC FOR -SHSN WILL BE ACROSS
THE HIGHER TERRAIN. FLYING CONDITIONS LOOK TO STAY VFR FOR THE
MAJORITY OF THE TIME. WESTERLY WINDS WILL BE AROUND 5 KTS.
OUTLOOK...
MON-WED...VFR. NO SIG WX.
THU...VFR/MVFR. CHC -RASN.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS ARE EXPECTED THE NEXT 5 DAYS RELATED TO QPF...AS
MAINLY DRY WEATHER OR SNOW PRODUCING SYSTEMS WILL IMPACT THE ALBANY
HYDRO SERVICE AREA /HSA/. MOST OF THESE WILL BE RATHER LIGHT.
SOME RIVER GAGES ARE EXHIBITING SIGNS OF ICE EFFECTS...AND RIVER
LEVEL READINGS LOOK UNREPRESENTATIVE. ICE WILL CONTINUE TO FORM
AND THICKEN ON ALL WATERWAYS IN THE ALY HSA THROUGH THE WEEKEND.
WE WILL HAVE TO MONITOR FOR ANY FREEZE UP JAMS...ESPECIALLY ALONG
THE NRN PERIPHERY OF THE HSA.
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...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...SND/GJM
NEAR TERM...BGM/SND/GJM
SHORT TERM...GJM
LONG TERM...IRL
AVIATION...FRUGIS
HYDROLOGY...GJM
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
347 AM CST SUN JAN 6 2013
.DISCUSSION...
ONE THING THAT LOOKS CERTAIN IS THAT WE WILL GET A NICE JANUARY
THAW COMING UP THIS WEEK. WHERE THERE ARE STILL QUESTIONS IS HOW
WARM IS SAID THAW...AND IS IT ACCOMPANIED WITH RAIN IN THE THU/FRI
TIMEFRAME. QUESTION MARKS DO NOT GO AWAY FOR THE WEEKEND IN TERMS
OF THE WEATHER...WITH THE ONLY THING THAT LOOKS CERTAIN BY THE END
OF THE WEEK INTO NEXT WEEKEND IS THAT THE MID SECTION OF THE
COUNTRY LOOKS TO BE MORE ACTIVE.
THE THAW IS COMING...JUST NOT TODAY. SFC LOW AT 3 AM WAS NEAR THE
MACKINAC STRAIGHTS. SEEING WIDESPREAD STRATUS ACROSS NRN MN
WITHIN CYCLONIC FLOW BEHIND THIS LOW. THIS STRATUS IS MAKING
INROADS SOUTH AND SHOULD BLANKET MUCH OF NW QUARTER OF THE MPX
CWA BY DAYBREAK. FOR NOW HAVE CLOUDS THINNING DURING THE
MORNING...WITH MOSTLY SUNNY SKIES INDICATED BY THE AFTERNOON...BUT
THE RAP /PER 925-850 MB RH/ KEEPS THE CLOUDS IN PLACE THROUGH THE
DAY. CERTAINLY WOULD NOT BE THE FIRST TIME STRATUS GOT TRAPPED
UNDER A DEVELOPING INVERSION...WHICH WE WILL SEE THANKS TO 12 HR
H5 HEIGHT RISES IN EXCESS OF 120M BY THE AFTERNOON. EVEN WITHOUT
THE CLOUD COVER...COOLER AIR THAT ARRIVED OVERNIGHT WILL HELP HOLD
TEMPERATURES TODAY BACK INTO THE TEENS AND 20S.
TONIGHT...WINDS WILL TURN OUT OF THE SW AND SHOULD BE QUITE STRONG
RIGHT THROUGH THE EVENING OUT AHEAD OF COLD THAT WILL BE MOVING
ACROSS NODAK. LLJ OUT AHEAD THE FRONT PROGGED BY THE GFS/NAM TO
BE AROUND 60 KTS...SO THIS WILL QUICKLY BRING WARMER AIR BACK INTO
THE REGION...WITH 925 MB TEMPS GETTING BACK UP AROUND THE 0C MARK
BY MONDAY AFTERNOON. THE ONLY THING HOLDING THE AREA BACK FROM
SEEING HIGHS IN THE MID AND EVEN UPPER 30S IS THE COLD FRONT
QUICKLY MOVE THROUGH IN THE MORNING...BUT STILL SHOULD SEE HIGHS A
FEW DEGS ON EITHER SIDE OF 30.
FOR TUESDAY...A FAIRLY SHARP AND NEGATIVELY TILTED H5 TROUGH IS
STILL FORECAST TO SWING THROUGH THE REGION. HAVE SEEN A SLIGHT SRN
SHIFT WITH THE ECMWF TOWARD THE GFS WITH QPF WITH THIS
WAVE...THOUGH IT STILL KEEPS QPF NORTH OF THE MPX CWA...WHERE IT
TAKES THE PV ANOMALY. THE FIM/GFS AND EVEN THE 06.00 GEM ARE NOW
BRINGING SOME PRECIP INTO THE NRN HALF OF THE MPX CWA. AT THIS
POINT...KEPT POPS BELOW 15% THOUGH DID ADD A MENTION OF SCT
FLURRIES ACROSS CENTRAL MN. MAIN REASON FOR NOT INCLUDING
MENTIONABLE POPS IS THAT THE PRIMARY SFC LOW...EVEN ON THE SRN
OUTLIER GFS IS PROGGED TO GO ACROSS SRN CANADA...WHICH WOULD HELP
KEEP BETTER PRECIP CHANCES UP ALONG THE INTERNATIONAL BORDER. EVEN
IF SNOW WERE TO OCCUR...IT WOULD BE ANOTHER HALF INCH OR LESS TYPE
SNOWFALL.
MODELS MAINTAIN DECENT AGREEMENT ON THE PROGRESSION OF THINGS NEXT
WEEK THROUGH WEDNESDAY...BUT QUICKLY DIVERGE AFTER THAT...WITH
EVEN RUN-TO-RUN CONSISTENCY WITHIN INDIVIDUAL MODELS BEING LESS
THAN IDEAL. AT ISSUE IS HOW THEY HANDEL THE CLOSED H5 LOW THAT IS
CURRENTLY NEAR SAN FRANCISCO. BY WEDNESDAY...THIS LOW WILL BE NEAR
THE BIG BEND REGION OF TX AS A DEEP AND POSITIVELY TILTED TROUGH
WORKS DOWN THE WEST COAST. AS ALL OF THIS IS GOING ON...AN
IMPRESSIVE RIDGE WILL BE BUILDING ACROSS THE ERN CONUS...WITH 590
DM HEIGHTS EXPECTED OVER FLA AND THE 576 DM LINE CLEAR UP TO THE
WI/IL BORDER. WHERE MODELS DIVERGE IS THE EXTENT WHICH THE CLOSED
LOW WILL INTERACT WITH THE WEST COAST TROUGH. OVER THE PAST 24 HRS
THE GFS AND ECMWF HAVE TRADED POSITIONS ON HOW TO HANDEL THE
WAVE...WITH THE GFS NOW BRINGING THE WAVE NORTH TOWARD THE GREAT
LAKES BY FRIDAY...WITH THE ECMWF TAKING THE WAVE ACROSS THE OHIO
VALLEY. THE GEM/FIM ARE MORE IN LINE WITH THE GFS...THOUGH A
LITTLE SLOWER. AT THIS POINT...GIVEN THE STRENGTH OF THE RIDGE
EXPECTED OVER THE SE...FIND IT HARD TO BELIEVE THE ECMWF SOLUTION
THAT IT WILL PLOW RIGHT THROUGH THE RIDGE AND WOULD FAVOR THE MORE
WRN SOLUTIONS. WHERE THERE IS AGREEMENT HOWEVER WITH THE
MODELS...IS THAT WHEREVER THE PRECIPITATION GOES...THICKNESSES
WILL BE WARM ENOUGH ACROSS THE MPX CWA FOR ALL RAIN ON THURSDAY.
IN FACT...MODELS DELAY THE ONSET OF THE COLD AIR BY A DAY
NOW...WITH THE ECMWF AND GEM SHOWING HIGHS IN THE 40S ON FRIDAY
ACROSS THE ERN HALF OF THE CWA...WHICH MEANS ANY TRANSITION BACK
TO SNOW POSSIBLY WAITING UNTIL AS LATE AS FRIDAY NIGHT OR
SATURDAY.
BESIDE THE POTENTIAL FOR RAIN...TEMPERATURE AND DEWPOINT FORECASTS
THURSDAY AND FRIDAY SHOW THE POTENTIAL FOR SOME AGGRESSIVE SNOW
MELT FOR JANUARY STANDARDS. BESIDE HIGHS POSSIBLY PUSHING 40 ONE
OR BOTH OF THE DAYS...THURSDAY NIGHT MAY SEE LOWS STAY ABOVE
FREEZING...WITH DEWPOINTS EVEN GETTING INTO THE MID/UPPER 30S.
EVEN WITHOUT ANY RAIN...THESE CONDITIONS WILL LIKELY LEAVE BARE
SPOTS IN THE SNOW COVER BY THIS WEEKEND.
AS FOR THE WEEKEND...MODEL AGREEMENT GETS NO BETTER. ABOUT ALL ONE
CAN SAY IS THAT THE WRN TROUGH WILL CONTINUE TO PUSH EAST...AND AS
IT DOES SO...MORE SEASONABLE AIR WILL MAKE A RETURN...WITH SOME
SNOW STILL LOOKING POSSIBLE.
&&
.AVIATION... /06Z TAF ISSUANCE/
PATCHY MVFR CEILINGS FROM KSTC THROUGH THE TWIN CITIES AND
EASTWARD INTO WEST CENTRAL WI WILL CONTINUE TO MEANDER SE EARLY IN
THE TAF PERIOD IN THE WAKE OF A COLD FRONT. A SMALL BREAK EXISTS TO
THE WEST BEFORE MORE WIDESPREAD MVFR CEILINGS ARE PUSHING IN FROM
THE DAKOTAS NEAR 20 KNOTS. SHORT TERM GUIDANCE SUGGESTS THIS
CLOUDINESS WILL REACH INTO KAXN BY 08Z AND INTO KRWF AND KSTC
AROUND 10Z. THIS WILL LIKELY PERSIST THROUGH DAYBREAK BEFORE
DIMINISHING DURING THE MORNING AS THE LOW LEVEL FLOW BECOMES MORE
ANTICYCLONIC. VFR CONDITIONS FOR THE AFTERNOON AND EVENING AS A
RIDGE OF HIGH PRESSURE MOVES BY. THE PRESSURE GRADIENT WILL TIGHTEN
SUNDAY NIGHT WITH SOUTH WINDS INCREASING TO NEAR 15 KNOTS FOR KRWF
AND KAXN. THIS GRADIENT WILL SPREAD INTO THE EASTERN TAF SITES
DURING THE NIGHT. WINDS MONDAY MORNING AT 1500 FEET ARE PROJECTED
TO BE NEAR 50 KNOTS.
KMSP...PATCHY MVFR CEILINGS WILL OCCUR EARLY THIS MORNING.
CEILINGS NEAR 015 SHOULD BEGIN MOVING IN BETWEEN 07Z-09Z.
CONFIDENCE INCREASING THAT THESE LOWER MVFR CEILINGS WILL PERSIST
INTO THE MID MORNING HOURS. VFR FOR THE AFTERNOON AND NIGHT.
NORTHWEST WINDS 6-9 KNOTS OVERNIGHT AND SUNDAY MORNING BACKING TO
THE WEST IN THE AFTERNOON AND THEN TO SOUTH 12 KNOTS SUNDAY NIGHT.
/OUTLOOK FOR KMSP/
MON...VFR. WINDS SW 12-15 KTS GUSTING 20 KTS.
TUE...VFR. WINDS S 4-8 KTS.
WED...VFR. WINDS WSW 5 TO 10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
MPG/RAH
AREA FORECAST DISCUSSION
NWS DULUTH MN
1136 PM CST SAT JAN 5 2013
.AVIATION.../06Z TAF ISSUANCE/
SKY COVER WILL CONTINUE TO DECREASE THIS MORNING FROM THE
WEST...WITH A MVFR DECK SCTRG OUT AT KDLH BY 12Z AND KHYR BY 15Z.
WEAK RIDGING ACROSS THE NORTHLAND WILL THEN RESULT IN VFR
CONDITIONS FOR THE REST OF THE TAF PERIOD. WINDS WILL BECOME
MAINLY LIGHT AND VARIABLE LATER THIS MORNING...THEN TURN OUT OF
THE SOUTHWEST AND STRENGTHEN BY LATE SUNDAY AFTERNOON...ESPECIALLY
ACROSS OUR WRN ZONES TO DULUTH.
&&
.PREV DISCUSSION... /ISSUED 723 PM CST SAT JAN 5 2013/
UPDATE...
LOW PRESSURE IN UPPER MICHIGAN CONTINUE TO MOVE EAST THIS
EVENING...WITH WINDS BECOMING NORTH OVER LAKE SUPERIOR...AND LOWER
CLOUDS MOVING OVER NORTHERN WISCONSIN AS WELL. MORE CLOUDS OVER
THE RED RIVER VALLEY WERE MOVING E-SE THIS EVENING...AND THE RAP
900-925MB CONDENSATION PRESSURE DEFICITS WERE HANDLING THIS PRETTY
WELL...AND IT BRINGS THESE CLOUDS TO OUR WESTERN BORDER LATE
TONIGHT. WE`LL HAVE TO KEEP AN EYE ON THESE AND INCREASE CLOUD
COVER IF THEY HAPPEN TO MOVE IN FASTER.
WE DON`T PLAN ON ANY MAJOR CHANGES TO THE GRIDS OVERNIGHT...WE
STILL EXPECT LAKE EFFECT SNOW SHOWERS TO DEVELOP IN THE
SNOWBELT...MAINLY IN IRON/ASHLAND COUNTIES. WE DID INCREASE
SNOWFALL A BIT OVER IRON COUNTY AS INVERSION LEVELS INCREASE
TONIGHT WITH DELTA-T`S FORECAST TO ABOUT 15-17C.
PREV DISCUSSION... /ISSUED 535 PM CST SAT JAN 5 2013/
AVIATION...00Z TAFS
IFR/LOW MVFR CEILINGS COVERED MUCH OF NORTHEAST MINNESOTA...AND
THEY WERE WORKING THEIR WAY SOUTH INTO NORTHWEST WISCONSIN AS
WELL. MORE LOW CEILINGS WERE OVER PORTIONS OF EASTERN NORTH
DAKOTA. WE EXPECT THOSE CEILINGS WILL WORK EAST THROUGH THE
NIGHT...BUT THE RAP WHICH IS HANDLING THEM PRETTY WELL...KEEPS
THEM WEST OF KINL/KBRD THROUGH 14Z. A SURFACE LOW OVER WESTERN
UPPER MICHIGAN WILL CONTINUE TO MOVE OFF TONIGHT...DRAWING THOSE
LOWER CEILINGS SOUTH AND EAST. WE KEPT THE MENTION OF THESE CLOUDS IN
THE KDLH/KHIB TAFS THROUGH ABOUT 7-8Z...AND UNTIL 15Z AT KHYR.
MOST AREAS WILL BE VFR ON SUNDAY...OUTSIDE OF SOME LAKE CLOUDS
ALONG THE SOUTH SHORE.
PREV DISCUSSION... /ISSUED 251 PM CST SAT JAN 5 2013/
SHORT TERM...
THIS AFTERNOON/TONIGHT THROUGH SUNDAY NIGHT...
MAIN CONCERNS IN THE SHORT TERM ARE FOCUSED AROUND THE CHANCE OF
LIGHT SNOW EXPECTED TO DEVELOP THIS EVENING ACROSS NE MN AND
LINGER THROUGH NW WI INTO SUNDAY MORNING...ALONG WITH TEMPERATURES
THROUGH THE NEAR TERM.
ATMOSPHERE REMAINS FAIRLY DRY ACROSS THE REGION WITH A SHARP UPPER
TROUGH OVER THE RED RIVER VALLEY MOVING EWD INTO NRN MN THIS
AFTERNOON. BENIGN SFC LOW CURRENTLY POSITIONED NEAR LAKE MILLE
LACS WITH LITTLE IN THE WAY OF CLOUD COVER ASSOCIATED WITH IT
ATTM. LOW LEVEL FLOW PATTERN WITH EAST WINDS OFF LAKE SUPERIOR
INTO THE ARROWHEAD HAVE ALLOWED LOW CLOUDS TO PERSIST OVER THE NRN
THIRD OF THE FORECAST AREA TODAY. THIS AREA OF LOW CLOUDS WILL
COMBINE WITH THE INCOMING S/W AND INCREASE IN AREAL COVERAGE
BEFORE DEVELOPING LIGHT SNOW/FLURRIES ALONG AND EAST OF HIGHWAY 53
EARLY THIS EVENING. ONLY LIGHT OR TRACE ACCUMULATIONS ARE EXPECTED
OVER NE MN TONIGHT.
BY LATE THIS EVENING...THE BL FLOW ACROSS WRN LAKE SUPERIOR WILL
BECOME MORE NRLY AS THE SFC LOW SLIDES FURTHER TO THE EAST. THE
COMBINATION OF 15 TO 25 KT NORTH WINDS OFF THE LAKE WITH A LONG
FETCH OVER WATER...A RELATIVELY DEEP BL ROUGHLY 3-4K FT...AND
COLD ENOUGH TEMPS ALOFT TO PRODUCE MODEST LOW LVL
INSTABILITY...THE POTENTIAL FOR LIGHT LAKE EFFECT SNOW ALONG THE
SOUTH SHORE ARISES. LAKE TEMPS ARE AROUND +2.7 DEG C AND 850MB
TEMPS WILL BE -11 TO -12 DEG C. KEPT WITH PREVIOUS FORECAST OF
LIKELY POPS FROM NRN BAYFIELD TO NRN ASHLAND/IRON COUNTIES FROM
06-12Z LATE TONIGHT/EARLY SUN MORNING...AND GENERALLY 1-2 INCHES
OF SNOW IN THIS AREA.
HIGH PRESSURE QUICKLY BUILDS IN SUNDAY AFTERNOON AND ALLOWS
CONDITIONS TO DRY OUT. SHOULD SEE MOSTLY SUNNY TO PARTLY CLOUDY
SKIES FOR THE END OF THE WEEKEND.
LOW TEMPERATURES TONIGHT WILL BE SOMEWHAT TRICKY AS CLOUD COVER
COULD END UP BEING PATCHY IN NATURE OVER PARTS OF NE MN. WILL
LIKELY SEE SINGLE DIGITS ABOVE AND BELOW ZERO ACROSS NRN MN...WITH
A FEW TEENS BELOW ZERO NOT OUT OF THE QUESTION WHERE ADDITIONAL
CLEARING OCCURS. AREAS TO THE EAST IN NW WI WILL BE SLIGHTLY
WARMER WITH ADDITIONAL CLOUD COVER ALMOST CERTAIN. SHOULD SEE
LOWER TO MID TEENS IN THIS AREA. ON SUNDAY...A LINGERING COLD AIR
MASS WILL ONLY ALLOW TEMPS TO REACH INTO THE UPPER TEENS TO MID
20S...EVEN WITH MOSTLY SUNNY SKIES IN THE AFTERNOON. LOWS SUNDAY
NIGHT WILL DROP INTO THE UPPER SINGLE DIGITS AND TEENS ABOVE
ZERO...WITH HIGH CLOUDS MOVING IN FROM THE NW.
LONG TERM...
MONDAY THROUGH SATURDAY...
AN UNSEASONABLY MILD PATTERN WILL CONTINUE THROUGHOUT THE
EXTENDED TIME PERIOD ACROSS THE NORTHLAND. IT ALSO LOOKS FAIRLY
QUIET FOR THE MOST PART. LOW PRESSURE MOVING ACROSS THE CENTRAL
CANADIAN PROVINCES WILL AFFECT AREAS MAINLY NORTH OF THE BORDER ON
MONDAY AND MONDAY NIGHT...WITH A FAIR AMOUNT OF SUNSHINE FURTHER
SOUTH. THE MODELS DIVERGE QUITE A BIT IN HOW THEY HANDLE A SYSTEM
ON TUESDAY AND WEDNESDAY. THE ECMWF AND GEM ARE FAIRLY SIMILAR BUT
THE GFS SHOWS A LOW PRESSURE SYSTEM DEVELOPING IN CENTRAL NORTH
DAKOTA BY 00Z WEDNESDAY. THE RESULT COULD BE SOME SCATTERED SNOW
SHOWERS TUESDAY NIGHT AND WEDNESDAY AS THE SYSTEM MOVES THROUGH.
HIGH PRESSURE WILL GENERALLY CONTROL LATER WEDNESDAY AND WEDNESDAY
NIGHT. THURSDAY LOOKS QUITE MILD WITH TEMPS WELL INTO THE 30S
AHEAD OF LOW PRESSURE DEVELOPING IN THE NORTHERN ROCKIES. THERE
ARE SOME HUGE MODEL DIFFERENCES BEGINNING ON FRIDAY AND CONTINUING
INTO THE WEEKEND SO KEEPING POPS LOW FOR NOW. THE GFS CONTINUES TO
TRY TO DEVELOP A MAJOR LOW BY NEXT WEEKEND...WHICH WOULD IMPACT
OUR AREA. THE ECMWF IS MUCH FURTHER SE AND NOT NECESSARILY OF MUCH
CONCERN FOR OUR CWA. DEFINITELY SOMETHING TO KEEP AN EYE ON...AS
THE GFS HAS BEEN REASONABLY CONSISTENT.
&&
.POINT TEMPS/POPS...
DLH 8 20 10 30 / 20 0 0 10
INL -1 17 12 28 / 10 0 0 10
BRD 4 21 12 31 / 10 0 0 10
HYR 12 22 9 33 / 30 10 0 10
ASX 15 24 13 34 / 50 20 0 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 10 AM CST SUNDAY FOR LSZ121-146>148.
&&
$$
AVIATION...BERDES
AREA FORECAST DISCUSSION
NWS BISMARCK ND
322 AM CST SUN JAN 6 2013
.SHORT TERM...TODAY THROUGH MONDAY...
THE MAIN CHALLENGE FOR THE SHORT TERM IS FOG AND STRATUS THIS
MORNING. OTHERWISE...THE BEGINNING OF A PERIOD OF ABOVE AVERAGE
TEMPERATURES WILL HIGHLIGHT THE SHORT TERM.
THE HRRR SO FAR HAS HAD A GOOD HANDLE ON THE STRATUS THROUGH THE
NIGHT THAT HAS SPREAD SOUTHEAST OUT OF SOUTHERN CANADA. EXPECT
MOST AREAS ALONG AND EAST OF A LINE FROM CROSBY THROUGH BISMARCK
AND LINTON TO BE UNDER THE STRATUS DECK BY 12 UTC. DID MAINTAIN THE
MENTION OF PATCHY FOG AND FLURRIES UNDER THIS DECK BASED UPON
SURFACE OBSERVATIONAL TRENDS THROUGH THE NIGHT. HOWEVER...THE
STRATUS DECK SHOULD QUICKLY BEGIN TO ERODE...ESPECIALLY BETWEEN
15-18 UTC...AS SOUTHWESTERLY WINDS IN THE 925-850 MB LAYER
INCREASE.
OTHERWISE FOR TODAY...ALL OF WESTERN AND CENTRAL NORTH DAKOTA WILL
RESIDE WITHIN THE WARM SECTOR OF A SURFACE LOW ACROSS SOUTHEASTERN
SASKATCHEWAN. GIVEN A LOW LEVEL WARM AIR ADVECTION
REGIME IN SOUTHERLY FLOW...THE CHALLENGE IS HOW MUCH WARM AIR CAN
BE MIXED TO THE SURFACE FROM AN INVERSION THAT WILL BE REINFORCED
BY THE SNOWPACK. THE TREND THE PAST COUPLE OF DAYS IN A SIMILIAR
SETUP HAS BEEN FOR THE STATISTICAL GUIDANCE TO BE ABOUT 3 TO 5
DEGREES TOO WARM...AND THE DETERMINISTIC MODELS TO ABOUT THE SAME
AMOUNT TOO COLD. THUS WILL USE A BLEND OF THE TWO GUIDANCE SUITES
WHICH YIELDS HIGHS IN THE LOWER 20S ACROSS THE JAMES RIVER VALLEY
WHERE THE LEAST MIXING IS EXPECTED...TO THE LOW TO MID 30S ACROSS
THE FAR WEST WHERE WINDS TURN SOUTHWEST AHEAD OF AN ADVANCING COLD
FRONT WHICH SHOULD ALLOW FOR GREATER MIXING HEIGHTS TO BE
ACHIEVED.
THE AFOREMENTIONED COLD FRONT PROPAGATES ACROSS THE AREA DURING
THE EVENING AND OVERNIGHT...WITH POST FRONTAL MIXING PREVENTING ANY
FOG FORMATION RESULTING FROM SNOW MELT. CANNOT RULE OUT AN ISOLATED
SNOW SHOWER ACROSS THE FAR NORTH WITH THE PASSAGE OF THE FRONT
CLOSER TO THE STRONGER UPPER LEVEL FORCING. HOWEVER...MOISTURE IS
LIMITED AND MAINTAINED A DRY FORECAST FOR TONIGHT.
FOR MONDAY...DESPITE BEING IN THE WAKE OF A COLD FRONT...GOOD
MIXING FROM WESTERLY WINDS OF 15 TO 20 KTS ARE EXPECTED TO ALLOW
TEMPERATURES TO MIX OUT TO VALUES SIMILIAR TO THOSE SEEN ON
SUNDAY...AND LIKELY WARMER ACROSS THE SOUTH CENTRAL AND JAMES
RIVER VALLEY. WITH A SMALL SPREAD IN FORECAST HIGHS ON THE 00 UTC
STATISTICAL AND DETERMINISTIC GUIDANCE...USED A BLEND OF BOTH
YIELDING HIGHS FROM THE MID 20S NORTH TO THE LOWER 30S SOUTH.
.LONG TERM...MONDAY NIGHT THROUGH SATURDAY...
THE MEDIUM RANGE MODEL CONSENSUS PROGS A CLIPPER SYSTEM TO TRAVERSE
WESTERN AND CENTRAL NORTH DAKOTA MONDAY NIGHT THROUGH TUESDAY. A
WINTRY MIX WILL BE POSSIBLE AROUND THE I-94 CORRIDOR WITH THE PRECIP
TYPE EXPECTED TO GENERALLY BE ALL SNOW NORTH OF I-94 TUESDAY. NEW
SNOWFALL ACCUMULATIONS ARE EXPECTED TO REMAIN LESS THAN 1 INCH.
MAINLY DRY CONDITIONS WITH WELL ABOVE NORMAL TEMPERATURES ARE
FORECAST FOR WEDNESDAY.
THE GEM/GFS/ECMWF HAVE SLOWED THE PROGRESSION OF A LONG WAVE TROUGH
ACROSS THE WESTERN CONUS AND ITS ATTENDANT COLD FRONT INTO NORTH
DAKOTA THURSDAY. GIVEN THE SLOWER PROGRESSION...MAINTAINED THE
SLIGHT CHANCES FOR PRECIPITATION WEST THURSDAY...THEN BROAD BRUSHED
CHANCE/SLIGHT CHANCE POPS ACROSS THE ENTIRE CWA THURSDAY NIGHT. THE
SLIGHT CHANCES FOR SNOW SHOULD TAPER OFF FRIDAY.
MUCH COLDER AIR IS THEN EXPECTED TO PLUNGE ACROSS THE NORTHERN
PLAINS BEHIND THE FRONT. WELL BELOW NORMAL TEMPERATURES ARE EXPECTED
FRIDAY AND SATURDAY AS A RESULT. HIGHS ARE GENERALLY EXPECTED TO
RANGE FROM THE SINGLE DIGITS TO THE TEENS ABOVE ZERO. LOWS ARE
FORECAST TO RANGE FROM THE SINGLE DIGITS BELOW TO SINGLE DIGITS
ABOVE ZERO BY THE END OF THE WEEK.
&&
.AVIATION...
IFR CIGS IN STRATUS WILL CONTINUE TO DIVE SOUTHEASTWARD
ACROSS CENTRAL AND EASTERN NORTH DAKOTA THIS MORNING. KBIS WILL BE
ON THE FRINGE OF THIS STRATUS DECK...HENCE THE TEMPO IFR GROUP.
HOWEVER...KMOT/KJMS SHOULD REMAIN IFR THROUGH MID-MORNING...THEN
BECOME VFR BY LATE MORNING. VFR CONDITIONS ARE THEN EXPECTED FOR
WESTERN AND CENTRAL NORTH DAKOTA FROM THIS AFTERNOON THROUGH THE
REMAINDER OF THE TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AYD
LONG TERM/AVIATION...TM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1240 AM CST SUN JAN 6 2013
.DISCUSSION...
SIGNIFICANT CHANGES TO OVERNIGHT SKY COVER WERE MADE WITH THIS
FORECAST UPDATE AS LOW LEVEL STRATUS CONTINUES TO SPREAD SOUTHEAST
OUT OF SOUTHERN CANADA. THE LATEST RUNS OF THE HRRR HAVE A GOOD
HANDLE ON THIS DECK...AND WILL FOLLOW IT FOR CLOUD COVER
THROUGH THE NIGHT...WITH ALL AREAS ALONG AND EAST OF A LINE FROM
CROSBY THROUGH BISMARCK AND FORT YATES TO BE UNDER THE DECK BY 12
UTC. BASED UPON THE LATEST SURFACE OBSERVATIONAL TRENDS...PATCHY
FOG AND FLURRIES ARE ALSO ASSOCIATED WITH THE STRATUS DECK AND
REFLECTED THIS IN THE GRIDS FOR ALL AREAS TO BE IMPACTED BY THE
STRATUS.
&&
.AVIATION...
A SHIELD OF MAINLY IFR STRATUS WILL CONTINUE TO DROP SOUTH THROUGH THE
OVERNIGHT HOURS. LATEST SATELLITE TRENDS AND SHORT RANGE RH PROGS
INDICATE ALL TAF SITES EXCEPT KDIK WILL BE IMPACTED...ESPECIALLY
KMOT/KBIS/KJMS. SOME PERIODS OF MVFR FOG ARE ALSO POSSIBLE. LOWER
CLOUDS WILL SCATTER OUT BY MID TO LATE MORNING AS SOUTHERLY WINDS
PICK UP.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
AVIATION...RK
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1054 PM CST SAT JAN 5 2013
.DISCUSSION.../ISSUED AT 930 PM CST/
LOW CLOUDS ARE CLEARING VERY STRONGLY. LINGERING BAND OF LOW LEVEL
MOISTURE WEST WAITING FOR WARM ADVECTION TO START LOOKS TOO WEAK
WITH CLOUDS THERE RAPIDLY DISSIPATING...AND GIVEN NEW NAM RH
FIELDS...REDEVELOPMENT NOT EXPECTED. SKIES SHOULD GO CLEAR TO MOSTLY
CLEAR TONIGHT. FOR THIS HAVE ALLOWED TEMPERATURES A LITTLE BETTER
LATE DROP AS WINDS CONTINUE TO DECREASE WITH LOWS 2 TO 4 DEGREES
LOWER THAN BEFORE. WHILE SOME WARM ADVECTION UPSTAIRS WILL START
SOON...SURFACE SHOULD BE IGNORED ON THIS TONIGHT. LOW TEMPS IN THE
SINGLE DIGITS EVERYWHERE AND MAYBE A ZERO HERE AND THERE.
&&
.AVIATION.../FOR THE 06Z TAF ISSUANCE/
MVFR STRATUS SHOULD EXIT FAR SOUTHERN PORTIONS OF THE FORECAST AREA
EARLY IN THE PERIOD...07Z-08Z...TAKING ANY FLURRIES ALONG WITH IT.
RELATIVELY NARROW BAND OF LOW MVFR-IFR STRATUS DRIFTING SOUTHEAST
THROUGH NORTHEAST/EAST CENTRAL SD AND FAR WESTERN MN AT THE START OF
THE PERIOD WILL SLIDE MAINLY EAST OF I-29 CORRIDOR...DRIFTING ACROSS
SOUTHWEST MN/NORTHWEST IA THROUGH EARLY SUNDAY MORNING. COULD SCRAPE
CLOSE ENOUGH TO KFSD TO GIVE BRIEF PERIOD OF MVFR-IFR CEILINGS 07Z
TO 09Z WINDOW...BUT CONFIDENCE IN WESTWARD EXTENT IS LOW...SO WILL
KEEP TAF IN VFR RANGE. LINGERING NORTHWESTERLY WIND GUSTS 20-25KTS
OVER SOUTHEAST HALF OF THE FORECAST AREA WILL CONTINUE TO SLOWLY
SUBSIDE THROUGH THE OVERNIGHT HOURS...WITH LIGHT/VARIABLE WINDS
BECOMING SOUTH MOST AREAS BY SUNDAY AFTERNOON. INCREASING SOUTHERLY
FLOW EXPECTED TO SPREAD ACROSS THE AREA LATE SUNDAY AFTERNOON AND
EVENING...WITH GUSTS 20-25KTS LIKELY WEST OF JAMES RIVER VALLEY LATE
SUNDAY AFTERNOON...AND OVER MUCH OF SOUTHEAST SD/SOUTHWEST MN SUNDAY
EVENING.
&&
.PREV DISCUSSION.../ISSUED AT 342 PM CST/
UPPER WAVE PUSHING ACROSS THE DAKOTAS THIS AFTERNOON...DRIVING COLD
FRONT INTO THE FAR EASTERN PORTIONS OF THE STATE AT MID AFTERNOON.
CLOUDS PUSHING IN WITH STRONG COLD AIR ADVECTION...AND WITH OFF
SURFACE TEMPS FALLING QUICKLY TOWARD THOSE FAVORING ICE NUCLEATION...
HAVE SEEN FLURRIES DROP IN TO PARTS OF EAST CENTRAL SOUTH DAKOTA.
THE CLOUDS AND FLURRIES WILL CONTINUE TO PUSH EAST AND SOUTHEAST
THIS EVENING...BUT IT IS CERTAINLY A CHALLENGE AS TO HOW QUICKLY TO
BRING IN A MORE PERMANENT CLEARING. RAP AND 18Z NAM ARE NOW IN
FAVOR OF HANGING BACK A PERIOD OF LOWER CLOUDS LATER INTO THE NIGHT
NEAR/WEST OF THE JAMES RIVER AND THEN DRIFTING EAST AS FLOW ALOFT
STARTS TO TURN A BIT MORE WESTERLY. THIS ALSO PRESENTS A LARGE
CHALLENGE TO TEMPERATURES...WHICH WILL PROVE ALMOST IMPOSSIBLE TO
GET CLOSE ON AN HOURLY TIME FRAME WITH IN AND OUT CLOUD TRENDS.
EXPECT A BETTER PUSH OF CLEARING THROUGH THE EASTERN CWA BY LATER
EVENING...BUT ENOUGH WIND OR A FEW MORE CLOUDS LIKELY TO KEEP TEMPS
FROM PLUNGING TOO FAR ANYWHERE. GENERALLY LOOKING FOR QUITE A FEW
SINGLE DIGITS...WITH READINGS AROUND 10 WEST AS WARMER AIR SHUNTS
EAST FAIRLY QUICKLY.
SUNDAY AGAIN PRESENTS A SMALL CHALLENGE TO TEMPS...WITH A VERY
WEAK GRADIENT THROUGH MIDDAY OR EVEN EARLY AFTERNOON IN THE FAR
SOUTHEAST. LOWER ELEVATION LOCATIONS COULD EASILY ONCE AGAIN FIND
THEMSELVES MIRED IN CHILLIER AIR...WITH THE INCREASING SOUTHERLY
GRADIENT MAINLY ACROSS SOUTHEAST SOUTH DAKOTA AND INTO SOUTHWEST
MINNESOTA DURING THE AFTERNOON. HIGH CLOUDS PUSHING ACROSS WOULD
ONLY ENHANCE THE POTENTIAL FOR THIS TO OCCUR...SO WAS CAREFUL TO
NOT WARM CONDITIONS IN THE EAST TOO MUCH...AND DID NUDGE SOME
TEMPERATURES DOWN ACROSS PARTS OF NW IA. THE WEST WILL BE OPEN TO
SOME BETTER WARMING...BUT EVEN THERE THE INVERSION WILL PRESENT A
BIT OF A CHALLENGE TO LOWER ELEVATION WARMING. /CHAPMAN
THE PATTERN OF MILD WEATHER WILL CONTINUE THROUGH MUCH OF THE WEEK
AS A MORE ZONAL PATTERN SETS UP FOR THE FIRST HALF OF THE WORK WEEK.
MILDER WEST TO SOUTHWEST FLOW WILL MAKE TEMPERATURES QUITE TRICKY TO
PINPOINT...PARTICULARLY REGARDING OVERNIGHT LOWS. FOR SUNDAY
NIGHT...BREEZY SOUTH TO SOUTHWEST WINDS WILL LIKELY RESULT IN A
NON-DIURNAL TEMPERATURE TREND WITH LOWS EXPECTED IN THE EVENING OR
SHORTLY AFTER MIDNIGHT...THEN SLOWLY RISING LATE. THE QUESTION IS
HOW COOL WE WILL BE ABLE TO FALL OFF IN THE EVENING. OTHERWISE...
HIGH TEMPERATURES FOR TUESDAY AND WEDNESDAY WILL LIKELY BE NEAR OR
JUST ABOVE FREEZING...WITH THE HIGHS IN THE LOW 40S POSSIBLE IN
SOUTH CENTRAL SD WHERE THE GREATEST POTENTIAL MIXING OF THE MILD LOW
LEVEL TEMPERATURES COULD OCCUR.
LATEST MODEL RUNS SHOWING A LITTLE BETTER AGREEMENT FOR THE SYSTEM
ON WEDNESDAY NIGHT AND THURSDAY...BUT DIVERGE A BIT LEADING INTO
NEXT WEEKEND. ALSO OF NOTE ARE SOME PRETTY BIG CHANGES FROM EARLIER
MODELS RUNS. LATEST 12Z RUNS OF GFS AND ECMWF ARE MUCH SLOWER AND
FURTHER SOUTH WITH THE CLOSED LOW SYSTEM...RESULTING IN LITTLE TO NO
IMPACT ACROSS OUR FORECAST AREA. WENT AHEAD AND REMOVED MENTION OF
POPS FOR WEDNESDAY GIVEN THE SLOWER TIMING. DECIDED TO KEEP MENTION
OF LOW CHANCE POPS MAINLY IN NORTHWEST IOWA ON THURSDAY GIVEN THE
RECENT INCONSISTENCIES BETWEEN MODEL RUNS...BUT DID TRIM BACK
COVERAGE AND QUITE A BIT FROM THE ALL BLEND...WHICH WAS BIASED FROM
THE 00Z ECMWF RUN. TEMPERATURES REMAIN QUITE MILD INTO THURSDAY...
BRINGING THE QUESTION OF PRECIPITATION TYPE IF THIS SYSTEM DOES
GRAZE OUR SOUTHEAST CWA. GIVEN WHAT LOOKS LIKE VERY MILD LOW/MID
LEVELS...PRECIPITATION TYPE MAY BECOME A CONCERN EARLY THURSDAY...
BUT WITH MANY FACTORS UP IN THE AIR...WILL KEEP IT SIMPLE WITH A
RAIN AND SNOW MIX.
THE NEXT AREA OF UNCERTAINTY IS REGARDING A STORM SYSTEM AROUND THE
SATURDAY TIME FRAME. MODELS CONTINUE TO FLIP FLOP WITH
SOLUTIONS...RESULTING IN LARGE TEMPERATURE AND POP DIFFERENCES. NOT
A WHOLE LOT OF CONFIDENCE...ESPECIALLY WITH THE VERY EXTREME GFS
SOLUTION. IT DOES LOOK LIKE A BIT OF A COOL DOWN FRIDAY AND SATURDAY
COMPARED TO EARLIER IN THE WEEK...BUT NOTHING TOO EXTREME. DID NOT
ALTER MUCH FROM THE ALLBLEND.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1138 PM CST SAT JAN 5 2013
.SHORT TERM...TONIGHT
645 PM CST SAT JAN 5 2013
HAVE MADE SOME UPDATES TO THE FORECAST THIS EVENING WITH THE
PROSPECTS FOR DRIZZLE/FREEZING DRIZZLE. FIRST...TEMPERATURES HAVE
REMAINED ABOVE FREEZING IN THE WARM SECTOR AHEAD OF THE COLD FRONT
THAT CURRENTLY RUNS THROUGH NORTHEAST IOWA UP TO A TRIPLE POINT IN
WESTERN WISCONSIN WITH A WARM FRONT EXTENDING EAST ACROSS
WISCONSIN TOWARD GREEN BAY. CEILINGS FROM NORTHEAST IOWA INTO
SOUTHWEST WISCONSIN HAVE NOT BEEN AS LOW AS YOU WOULD WANT FOR
DRIZZLE TO OCCUR WITH THEM BEING AT 2-4KFT. OBSERVATIONS FROM DOWN
IN THIS REGION ALL SHOW VISIBILITY UP AT GREATER THAN 6SM WITH NO
REPORTS OF DRIZZLE THIS AFTERNOON/EARLY EVENING. 05.22Z RAP
SOUNDINGS OUT OF DBQ SEEM TO PAINT THE PICTURE WELL WITH A
SATURATED...PROBABLY OVERLY SATURATED...LOW LEVEL WITH NO VERTICAL
MOTIONS. BASED ON THESE FACTORS...HAVE REMOVED THE FREEZING
DRIZZLE/DRIZZLE MENTION FOR THIS EVENING.
THE SECOND WAVE THEN COMES IN AS A SECONDARY COLD FRONT WHICH
CURRENTLY IS DROPPING SOUTH ON THE BACK SIDE OF THE SURFACE LOW
ACROSS SOUTHERN MINNESOTA. THERE IS A BRIEF PERIOD OF
CLEARING...BUT THEN THERE IS A PATCH OF LOW LEVEL CLOUD COVER
TRACKING TO THE SOUTHEAST FROM SOUTH DAKOTA INTO CENTRAL IOWA.
MODELS HAVE BEEN OVER-DOING THE LOW LEVEL MOISTURE WITH THIS
FEATURE AND SHOW THAT WE SHOULD BE COMPLETELY OVERCAST AT THIS
POINT. HAVE LEFT SKY CONDITIONS AS MOSTLY CLOUDY TO CLOUDY
TONIGHT...BUT THAT MAY BE ON THE PESSIMISTIC SIDE GIVEN CURRENT
UPSTREAM CONDITIONS. 05.22Z RAP SOUNDINGS DO SHOW THAT IF THE LOW
LEVEL DECK DOES OCCUR THAT IT SHOULD BECOME COLDER THAN -8C THAT
ICE WOULD BE INTRODUCED. WITH WEAK FORCING...SHOULD SEE SOME
FLURRIES/SNOW SHOWERS WITH IT. THE LOW VISIBILITIES CURRENTLY
OCCURRING IN WEST CENTRAL MINNESOTA ARE FROM SNOW SHOWERS THOUGH
THEY ARE NOT SHOWING UP ON RADAR BECAUSE THE CLOUD DECK IS JUST A
FEW HUNDRED FEET OFF THE GROUND AND BELOW THE RADAR BEAM. THIS
AREA APPEARS TO BE RUNNING SOUTH OF THE FORECAST AREA...BUT WILL
HAVE TO MONITOR IT FOR WHETHER SOME SMALL ACCUMULATIONS NEED TO BE
ADDED OVERNIGHT.
.LONG TERM...TUESDAY THROUGH SATURDAY
201 PM CST SAT JAN 5 2013
MEDIUM RANGE MODELS HAVE STARTED TO COME INTO BETTER AGREEMENT
WITH THE SYSTEM EXPECTED TO IMPACT THE GREAT LAKES FOR THE LATTER
HALF OF THE WEEK. THE 05.00Z ECMWF HAS REMAINED CONSISTENT WITH
ITS PREVIOUS RUNS ON THE TRACK OF THE SYSTEM WHILE THE 05.12Z GFS
HAS SHIFTED CONSIDERABLY TOWARD THE ECMWF SOLUTION. THE MODELS ARE
NOW VERY SIMILAR IN TIMING BUT THE GFS STILL DOES NOT BRING THE
SYSTEM AS FAR NORTH AS THE ECMWF. BY 11.00Z /FRIDAY EVENING/ THE
ECMWF PLACES THE UPPER LEVEL LOW NEAR THE WISCONSIN-ILLINOIS
BORDER BETWEEN KDBQ AND KRST WHILE THE GFS IS FARTHER SOUTH NEAR
KSTL. THE AGREEMENT THAT WAS IN PLACE HAS BEEN THROWN OUT THE
WINDOW BY THE 05.12Z ECMWF HAS IT HAS COME IN SLOWER AND FARTHER
SOUTH AND IS NOT SIMILAR WITH ITS TRACK TO THE GFS. WITH THE
DISPARITY BETWEEN THE MODELS...THE ONLY CHANGE MADE TO THE MODEL
CONSENSUS GRIDS WAS TO WEDNESDAY NIGHT. WITH THE ECMWF NOW BEING
SLOWER...IT SUGGESTS THE PRECIPITATION WILL NOT MOVE IN UNTIL
THURSDAY...SO WILL NOW GO WITH A DRY WEDNESDAY NIGHT. THE
PRECIPITATION FROM THIS SYSTEM SHOULD START TO MOVE OUT THURSDAY
NIGHT OR FRIDAY BUT WILL QUICKLY BE FOLLOWED BY THE NEXT SYSTEM.
THE MODELS MAINTAIN A SOUTHWEST FLOW ALOFT BEHIND THIS SYSTEM AND
QUICKLY EJECT OUT ANOTHER SYSTEM FROM THE SOUTHERN ROCKIES. THE
ECMWF IS QUICKER AND FARTHER NORTH THAN THE GFS IN THE UPPER
LEVELS...BUT THE SURFACE TRACKS LOOK TO BE SIMILAR GOING FROM NEAR
KMCI TOWARD KMKE EITHER SATURDAY OR SATURDAY NIGHT. THE ECMWF
SUGGESTS THE FIRST SYSTEM WILL BRING ENOUGH WARM AIR NORTH TO
PRODUCE PRIMARILY RAIN OR A RAIN/SNOW MIX. HOWEVER...THE
BAROCLINIC ZONE LEFT BEHIND MAY BE JUST TO THE SOUTHEAST GIVING
THE SECOND SYSTEM ENOUGH COLD AIR TO WORK WITH TO PRODUCE MAINLY
SNOW.
&&
.AVIATION...THROUGH 06Z MONDAY
1138 PM CST SAT JAN 5 2013
CONFIDENCE IS NOT HIGH WITH THE SKY CONDITIONS OVERNIGHT AS THE
LOW LEVEL CLOUD DECK HAS NOT FILLED IN AS ANTICIPATED ACROSS THE
REGION. HOWEVER...ANOTHER ROUND OF MVFR 1-2.5KFT STRATUS APPEARS
TO BE DROPPING SOUTH OF OUT NORTHWEST WISCONSIN AND NORTHEAST
MINNESOTA PER THE LATEST IR SATELLITE IMAGERY/SURFACE
OBSERVATIONS. WILL CARRY SOME LOWER CEILINGS THROUGH THE OVERNIGHT
HOURS TO ACCOUNT FOR THIS WHICH SHOULD HOLD ON INTO THE MORNING
HOURS AND POSSIBLY INTO THE EARLY AFTERNOON. CAN NOT RULE OUT A
FEW FLURRIES AS THIS CLOUD DECK MOVES IN...BUT THEY SHOULD NOT BE
STRONG ENOUGH TO DROP VISIBILITY DOWN BELOW 6SM. SKIES SHOULD
CLEAR INTO THE AFTERNOON ON SUNDAY AS THE SYSTEM PULLS OFF TO THE
EAST AND DRIER AIR MOVES IN BEHIND IT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
201 PM CST SAT JAN 5 2013
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...04
AVIATION...HALBACH
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
621 AM CST SUN JAN 6 2013
.UPDATE...
UPDATED FOR AVIATION DISCUSSION BELOW.
&&
.PREV DISCUSSION.../ISSUED AT 347 AM CST SUN JAN 6 2013/
ONE THING THAT LOOKS CERTAIN IS THAT WE WILL GET A NICE JANUARY
THAW COMING UP THIS WEEK. WHERE THERE ARE STILL QUESTIONS IS HOW
WARM IS SAID THAW...AND IS IT ACCOMPANIED WITH RAIN IN THE THU/FRI
TIMEFRAME. QUESTION MARKS DO NOT GO AWAY FOR THE WEEKEND IN TERMS
OF THE WEATHER...WITH THE ONLY THING THAT LOOKS CERTAIN BY THE END
OF THE WEEK INTO NEXT WEEKEND IS THAT THE MID SECTION OF THE
COUNTRY LOOKS TO BE MORE ACTIVE.
THE THAW IS COMING...JUST NOT TODAY. SFC LOW AT 3 AM WAS NEAR THE
MACKINAC STRAIGHTS. SEEING WIDESPREAD STRATUS ACROSS NRN MN
WITHIN CYCLONIC FLOW BEHIND THIS LOW. THIS STRATUS IS MAKING
INROADS SOUTH AND SHOULD BLANKET MUCH OF NW QUARTER OF THE MPX
CWA BY DAYBREAK. FOR NOW HAVE CLOUDS THINNING DURING THE
MORNING...WITH MOSTLY SUNNY SKIES INDICATED BY THE AFTERNOON...BUT
THE RAP /PER 925-850 MB RH/ KEEPS THE CLOUDS IN PLACE THROUGH THE
DAY. CERTAINLY WOULD NOT BE THE FIRST TIME STRATUS GOT TRAPPED
UNDER A DEVELOPING INVERSION...WHICH WE WILL SEE THANKS TO 12 HR
H5 HEIGHT RISES IN EXCESS OF 120M BY THE AFTERNOON. EVEN WITHOUT
THE CLOUD COVER...COOLER AIR THAT ARRIVED OVERNIGHT WILL HELP HOLD
TEMPERATURES TODAY BACK INTO THE TEENS AND 20S.
TONIGHT...WINDS WILL TURN OUT OF THE SW AND SHOULD BE QUITE STRONG
RIGHT THROUGH THE EVENING OUT AHEAD OF COLD THAT WILL BE MOVING
ACROSS NODAK. LLJ OUT AHEAD THE FRONT PROGGED BY THE GFS/NAM TO
BE AROUND 60 KTS...SO THIS WILL QUICKLY BRING WARMER AIR BACK INTO
THE REGION...WITH 925 MB TEMPS GETTING BACK UP AROUND THE 0C MARK
BY MONDAY AFTERNOON. THE ONLY THING HOLDING THE AREA BACK FROM
SEEING HIGHS IN THE MID AND EVEN UPPER 30S IS THE COLD FRONT
QUICKLY MOVE THROUGH IN THE MORNING...BUT STILL SHOULD SEE HIGHS A
FEW DEGS ON EITHER SIDE OF 30.
FOR TUESDAY...A FAIRLY SHARP AND NEGATIVELY TILTED H5 TROUGH IS
STILL FORECAST TO SWING THROUGH THE REGION. HAVE SEEN A SLIGHT SRN
SHIFT WITH THE ECMWF TOWARD THE GFS WITH QPF WITH THIS
WAVE...THOUGH IT STILL KEEPS QPF NORTH OF THE MPX CWA...WHERE IT
TAKES THE PV ANOMALY. THE FIM/GFS AND EVEN THE 06.00 GEM ARE NOW
BRINGING SOME PRECIP INTO THE NRN HALF OF THE MPX CWA. AT THIS
POINT...KEPT POPS BELOW 15% THOUGH DID ADD A MENTION OF SCT
FLURRIES ACROSS CENTRAL MN. MAIN REASON FOR NOT INCLUDING
MENTIONABLE POPS IS THAT THE PRIMARY SFC LOW...EVEN ON THE SRN
OUTLIER GFS IS PROGGED TO GO ACROSS SRN CANADA...WHICH WOULD HELP
KEEP BETTER PRECIP CHANCES UP ALONG THE INTERNATIONAL BORDER. EVEN
IF SNOW WERE TO OCCUR...IT WOULD BE ANOTHER HALF INCH OR LESS TYPE
SNOWFALL.
MODELS MAINTAIN DECENT AGREEMENT ON THE PROGRESSION OF THINGS NEXT
WEEK THROUGH WEDNESDAY...BUT QUICKLY DIVERGE AFTER THAT...WITH
EVEN RUN-TO-RUN CONSISTENCY WITHIN INDIVIDUAL MODELS BEING LESS
THAN IDEAL. AT ISSUE IS HOW THEY HANDEL THE CLOSED H5 LOW THAT IS
CURRENTLY NEAR SAN FRANCISCO. BY WEDNESDAY...THIS LOW WILL BE NEAR
THE BIG BEND REGION OF TX AS A DEEP AND POSITIVELY TILTED TROUGH
WORKS DOWN THE WEST COAST. AS ALL OF THIS IS GOING ON...AN
IMPRESSIVE RIDGE WILL BE BUILDING ACROSS THE ERN CONUS...WITH 590
DM HEIGHTS EXPECTED OVER FLA AND THE 576 DM LINE CLEAR UP TO THE
WI/IL BORDER. WHERE MODELS DIVERGE IS THE EXTENT WHICH THE CLOSED
LOW WILL INTERACT WITH THE WEST COAST TROUGH. OVER THE PAST 24 HRS
THE GFS AND ECMWF HAVE TRADED POSITIONS ON HOW TO HANDEL THE
WAVE...WITH THE GFS NOW BRINGING THE WAVE NORTH TOWARD THE GREAT
LAKES BY FRIDAY...WITH THE ECMWF TAKING THE WAVE ACROSS THE OHIO
VALLEY. THE GEM/FIM ARE MORE IN LINE WITH THE GFS...THOUGH A
LITTLE SLOWER. AT THIS POINT...GIVEN THE STRENGTH OF THE RIDGE
EXPECTED OVER THE SE...FIND IT HARD TO BELIEVE THE ECMWF SOLUTION
THAT IT WILL PLOW RIGHT THROUGH THE RIDGE AND WOULD FAVOR THE MORE
WRN SOLUTIONS. WHERE THERE IS AGREEMENT HOWEVER WITH THE
MODELS...IS THAT WHEREVER THE PRECIPITATION GOES...THICKNESSES
WILL BE WARM ENOUGH ACROSS THE MPX CWA FOR ALL RAIN ON THURSDAY.
IN FACT...MODELS DELAY THE ONSET OF THE COLD AIR BY A DAY
NOW...WITH THE ECMWF AND GEM SHOWING HIGHS IN THE 40S ON FRIDAY
ACROSS THE ERN HALF OF THE CWA...WHICH MEANS ANY TRANSITION BACK
TO SNOW POSSIBLY WAITING UNTIL AS LATE AS FRIDAY NIGHT OR
SATURDAY.
BESIDE THE POTENTIAL FOR RAIN...TEMPERATURE AND DEWPOINT FORECASTS
THURSDAY AND FRIDAY SHOW THE POTENTIAL FOR SOME AGGRESSIVE SNOW
MELT FOR JANUARY STANDARDS. BESIDE HIGHS POSSIBLY PUSHING 40 ONE
OR BOTH OF THE DAYS...THURSDAY NIGHT MAY SEE LOWS STAY ABOVE
FREEZING...WITH DEWPOINTS EVEN GETTING INTO THE MID/UPPER 30S.
EVEN WITHOUT ANY RAIN...THESE CONDITIONS WILL LIKELY LEAVE BARE
SPOTS IN THE SNOW COVER BY THIS WEEKEND.
AS FOR THE WEEKEND...MODEL AGREEMENT GETS NO BETTER. ABOUT ALL ONE
CAN SAY IS THAT THE WRN TROUGH WILL CONTINUE TO PUSH EAST...AND AS
IT DOES SO...MORE SEASONABLE AIR WILL MAKE A RETURN...WITH SOME
SNOW STILL LOOKING POSSIBLE.
&&
.AVIATION.../12Z TAF ISSUANCE/
TWO AREAS OF CIGS TO BE CONCERNED ABOUT THIS MORNING. ONE IS OVER
WRN WI AND IS PRIMARILY MVFR. THE OTHER IS A NARROW FINGER OF
IFR CIGS ACROSS WRN MN. RAP13 SEEMS TO HAVE A GOOD HANDLE ON THESE
AREAS...SO FOLLOWED THIS SOLUTION WITH A FEW TWEAKS TOWARD THE
LAMP GUIDE. THE CIGS OVER WRN MN SHOULD SLIDE EAST SLOWLY THIS
MORNING AND BEGIN DISSIPATING. THE BACK EDGE IS ABOUT OVER RWF
AND SHOULD CLEAR AXN AROUND 14-15Z. IT WILL HOWEVER BEGIN TO AFFECT
STC AROUND 13Z...AND REMAIN NEARLY STATIONARY UNDER THE RIDGE AXIS
THROUGH THE MORNING BEFORE DISSIPATING SOMETIME AROUND 18Z.
FURTHER EAST...RNH AND MSP SHOULD BE VFR THROUGH THE PERIOD BEING
SANDWICHED BETWEEN THE TWO AREAS OF STRATUS. FINALLY...EAU WILL
SEE IMPROVING CONDITIONS AS THE MVFR STRATUS ROTATES OUT TO THE
EAST THIS MORNING.
WINDS ARE EXPECTED TO TURN SOUTHERLY AND STRENGTHEN THIS EVENING.
FORECAST SOUNDINGS STILL INDICATE THE POTENTIAL FOR 50+ KT WINDS
ABOVE 1000FT. A PRETTY DEEP INVERSION SHOULD DAMPEN WIND GUST
POTENTIAL TO LESS THAN 25 KTS AT THE SURFACE AND HAS ALLOWED THE
EXCLUSION OF WIND SHEAR MENTION ATTM.
KMSP...VFR CONDITIONS EXPECTED AS TWO AREAS OF STRATUS LIKELY REMAIN
REMOVED FROM THE VICINITY OF THE TERMINAL. NORTHWEST WINDS WILL
BACK SOUTHWEST THIS AFTERNOON AND TO SOUTH TONIGHT. SPEEDS WILL
REMAIN LIGHT THROUGH TODAY...THEN INCREASE WITH LLJ PUSHING
OVERHEAD TONIGHT.
/OUTLOOK FOR KMSP/
MON...VFR. WINDS SW 10 KTS.
TUE...VFR. WINDS SE 4-8 KTS.
WED...VFR. WINDS S 10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
MPG/BORGHOFF
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1001 AM EST SUN JAN 6 2013
.SYNOPSIS...
A WEAK AREA OF LOW PRESSURE WILL BRING MINOR SNOW ACCUMULATIONS TO
MOST LOCATIONS THIS AFTERNOON AND EVENING...BUT SNOWS WILL BE
A BIT STEADIER EAST OF LAKE ONTARIO. HIGH PRESSURE WILL THEN BUILD
INTO THE OHIO VALLEY AND EASTERN GREAT LAKES FOR THE FIRST HALF OF
NEXT WEEK WITH DRY WEATHER AND WARMING TEMPERATURES. THE JANUARY
THAW WILL LAST RIGHT THROUGH NEXT WEEKEND WITH MILD TEMPERATURES AND
INCREASING CHANCES OF RAIN.
&&
.NEAR TERM /THROUGH TONIGHT/...
A WIDESPREAD AREA OF MAINLY LIGHT WET SNOW HAS BLOSSOMED ACROSS ALL
OF WESTERN NY THIS MORNING...MIXED WITH RAIN ALONG THE LAKESHORES
AND NIAGARA COUNTY. THIS APPEARS TO BE TIED TO WEAK ASCENT JUST
AHEAD OF A WEAK SHORTWAVE APPARENT IN WATER VAPOR IMAGERY CROSSING
CENTRAL LAKE ERIE THIS MORNING. MODEL GUIDANCE IS NOT CAPTURING THIS
AT ALL...SO HAVE UPDATED THE GRIDS BASED SOLELY ON EXTRAPOLATION OF
CURRENT RADAR TRENDS FOR THE NEXT 6 HOURS OR SO. EXPECT STEADY LIGHT
SNOW ACROSS WESTERN NY THROUGH AT LEAST EARLY AFTERNOON. AT LOWER
ELEVATIONS TEMPERATURES ARE ALREADY ABOVE FREEZING...SO JUST EXPECT
LESS THAN AN INCH OF ACCUMULATION ON EXISTING SNOW...WITH ROADS JUST
REMAINING WET. SOME RAIN WILL ALSO MIX IN AT LOWER ELEVATIONS. THE
HIGHER TERRAIN OF THE SOUTHERN TIER MAY PICK UP AN INCH OR SO TODAY
AS TEMPERATURES REMAIN CLOSER TO THE FREEZING MARK.
IT APPEARS THIS AREA OF WET SNOW WILL STRUGGLE TO MOVE EAST...WITH
JUST A FEW BRIEF SNOW OR RAIN SHOWERS FROM THE GENESEE VALLEY INTO
CENTRAL NY THIS AFTERNOON. EAST OF LAKE ONTARIO EXPECT A SIMILAR
BLOSSOMING OF LIGHT SNOW BY EARLY AFTERNOON AS THE SHORTWAVE MOVES
EAST AND INTERACTS WITH AN OLD FRONTAL BOUNDARY STILL IN THE
VICINITY. EXPECT AROUND AN INCH THERE THIS AFTERNOON...WITH UP TO 2
INCHES ACROSS THE TUG HILL AND WESTERN FOOTHILLS OF THE ADIRONDACKS.
THE NEXT PART OF THIS GENERALLY WEAK SYSTEM WILL IMPACT THE REGION
DURING THE LATE AFTERNOON AND EVENING HOURS. THE KEY WILL BE THE
PASSAGE OF ANOTHER SHORT WAVE...WHICH WILL HELP DRIVE A COLD FRONT
ACROSS THE REGION. HOWEVER...THERE WILL BE WELL ALIGNED SOUTHWEST
FLOW AHEAD OF THIS...WITH AMPLE MOISTURE AND A LONG FETCH. 850 MB
TEMPERATURES WILL ONLY BE AROUND -7C...WITH LAKE INDUCED CAPES
BARELY MEASURABLE. HOWEVER...THIS WILL PROBABLY BE ENOUGH TO BOOST
MOISTURE A BIT...AND BRING A PERIOD OF SNOW TO MOST LOCATIONS. THE
QPF FORECAST OF MOST OF THE HIGHER RESOLUTION MODEL GUIDANCE
SUGGESTS THIS ENHANCEMENT WILL BE A SIGNIFICANT PART OF WHATEVER
SNOW FALLS...AND SEVERAL RUNS OF THE HRRR ARE PRODUCING PLAUSIBLE
SOLUTIONS.
THE LIONS SHARE OF SNOW WILL FALL BETWEEN 21Z AND 06Z...WITH MOST
LOCATIONS LIKELY TO SEE ONLY A FEW HOURS OF LIGHT TO MODERATE
SNOWS SOMEWHERE IN THAT TIMEFRAME. EXPECT AN INCH OR TWO TO FALL EAST
OF LAKE ERIE...MAINLY ACROSS THE HIGHER TERRAIN WITH AN ADDED BOOST
FROM UPSLOPE FLOW. STEADIER SNOWS WILL FALL EAST OF LAKE
ONTARIO...WITH STEADIER SNOWS LIKELY TO DEVELOP THIS AFTERNOON...AND
CONTINUE INTO THE EVENING. HRRR GUIDANCE SUGGESTS A BAND OF MODERATE
SNOW WILL DEVELOP...WITH A TOTAL OF 2 TO 4 INCHES OF SNOW LIKELY IN
THAT REGION THIS AFTERNOON AND EVENING. THIS IS IN LINE WITH THE
SEVERAL RUNS OF THE RGEM/NAM. ONE LIMITING FACTOR MAY BE
TEMPERATURES...WHICH WILL BE NEAR OR ABOVE FREEZING THROUGH THE
EVENT AT LOWER ELEVATIONS...WHICH MAY TEMPER ACCUMULATIONS NEAR LAKE
ONTARIO. THE LEAST AMOUNT OF SNOW WILL FALL FROM THE SOUTH SHORE OF
LAKE ONTARIO INTO THE FINGER LAKES...WHERE THE LEAST PRECIP AND
WARMEST BOUNDARY LAYER TEMPERATURES WILL BE FOUND. SOME OF THESE
AREAS MAY SEE NO ACCUMULATION AT ALL.
THE FRONT WILL PUSH SOUTH OF THE REGION LATE TONIGHT...WHICH SHOULD
BRING DRIER AIR INTO THE REGION. SOME LIGHT LAKE EFFECT SNOW SHOWERS
OR FLURRIES CAN/T BE RULED OUT...BUT WHAT DOES DEVELOP SHOULD BE
SHORT LIVED GIVEN THE SHORT FETCH IN THE NORTHERLY FLOW AND THE DRY
AIR UPSTREAM. HOWEVER...THIS SET UP IS FAVORABLE FOR CLOUDS TO BE
QUITE PERSISTENT BEHIND THE FRONT...AS ANY LAKE MOISTURE GETS
TRAPPED BENEATH THE INVERSION. BECAUSE OF THIS...HEDGE ON THE WARM
SIDE OF GUIDANCE FOR LOW TEMPERATURES. EXPECT LOWS IN THE LOWER 20S
IN MOST LOCATIONS...BUT SIGNIFICANTLY COOLER TEMPERATURES ARE
POSSIBLE EAST OF LAKE ONTARIO WHERE CLEARING IS POSSIBLE.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
A QUIET PERIOD IS EXPECTED MONDAY AND TUESDAY WITH A SLOW MODERATING
TREND TO CONTINUE THROUGH THE WORK WEEK.
FOR MONDAY A FEW FLURRIES OR LIGHT SNOW SHOWERS MAY STILL BE FALLING
OFF LAKE ONTARIO SOUTHEAST OF THE LAKE EARLY IN THE MORNING HOURS.
TEMPERATURES ALOFT AT 850 HPA UNDER WARM AIR ADVECTION ARE ONLY
MARGINAL FOR LAKE EFFECT SNOW...AND WITH LOW LEVEL LIFT ESSENTIALLY
GONE AND MOISTURE LACKING FROM WITHIN THE SNOW GROWTH ZONE...ANY
SUPPORT FOR LAKE EFFECT SNOW WILL NOT BE CONDUCIVE...THUS ANY LAKE
ACTIVITY SHOULD DIMINISH QUICKLY THROUGH THE MORNING. THE 850 HPA
RIDGE REMAINS TO OUR WEST TO START THE DAY AND A BROKEN LOW LAYER OF
CLOUDS ACROSS HIGHER TERRAIN OF WNY...GENESEE VALLEY AND NORTHERN
FINGER LAKES REGION WILL LIKELY START THE DAY. AS THIS RIDGE AXIS
PASSES THE AREA FROM WEST TO EAST THROUGH THE MORNING HOURS EXPECT
INCREASING AMOUNTS OF SUNSHINE. DESPITE A GOOD DEAL OF SUNSHINE
THROUGH THE AFTERNOON HOURS TEMPERATURES WILL HOLD TO AROUND NORMAL
ACROSS WESTERN NEW YORK...WITH HIGHS AROUND 30...AND SLIGHTLY BELOW
NORMAL ACROSS THE EASTERN LAKE ONTARIO REGION WITH LOW TO MID
20S.
MONDAY NIGHT A BROAD AREA OF HIGH PRESSURE WILL BE FOUND ALONG THE
ATLANTIC COASTLINE WITH A SOUTHWEST RETURN FLOW ACROSS THE EASTERN
GREAT LAKES REGION. THIS WILL PROHIBIT TEMPERATURES FROM
PLUNGING...AND IN FACT THEY MAY RISE A DEGREE OR TWO OVERNIGHT
ACROSS THE DOWN SLOPE AREAS OF WNY. TOWARDS THE NORTHERN FINGER
LAKES AND EASTERN LAKE ONTARIO REGION WHERE THE SOUTHWEST FLOW WILL
NOT BE AS GREAT TEMPERATURES WILL FALL BACK INTO THE TEENS TO AROUND
20. TO THE WEST MILDER OVERNIGHT LOWS ARE EXPECTED...WITH LOW 20S
ACROSS INTERIOR SOUTHWEST NEW YORK AND UPPER 20S FOR THE LOWER
ELEVATIONS.
LATE MONDAY NIGHT AND TUESDAY A STORM SYSTEM WILL PASS WELL TO OUR
NORTH ACROSS JAMES BAY AND CENTRAL/NORTHERN QUEBEC. A TIGHTENING
PRESSURE GRADIENT BETWEEN THIS SYSTEM AND HIGH PRESSURE ALONG THE
EASTERN SHORELINE WILL ALLOW WINDS TO BECOME BREEZY THROUGH THE DAY
TUESDAY...ESPECIALLY OFF THE LAKES ON A SOUTHWEST FLOW. A FEW CLOUDS
WILL LIKELY PASS ACROSS THE REGION THOUGH STILL A GOOD DEAL OF
SUNSHINE IS EXPECTED. TEMPERATURES ALOFT AT 850 HPA WILL BE SEVERAL
DEGREES WARMER THAN MONDAY...AND WITH THESE SOUTHWEST WINDS
TEMPERATURES SHOULD BE A BIT WARMER THAN MONDAY...WITH HIGHS
MODERATING INTO THE MID TO UPPER 30S. REMAINING DRY OVERNIGHT THOUGH
CLOUDS WILL START TO THICKEN MORE AS A SECOND STORM SYSTEM TAKES A
SLIGHTLY MORE SOUTHERN TRACK THROUGH CANADA. LOWS TUESDAY NIGHT WILL
FALL BACK INTO THE MID 20S TO AROUND 30 ACROSS THE REGION.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
A GENERAL ZONAL FLOW WILL REMAIN IN PLACE ALONG THE CANADIAN/U.S.
BORDER THROUGH THURSDAY. AFTER THAT...A MORE AMPLIFIED FLOW WILL SET
UP THURSDAY NIGHT THROUGH SATURDAY AS A DEEPENING TROUGH DIGS INTO
THE WESTERN U.S...WHILE A FLAT RIDGE REMAINS IN PLACE OVER EASTERN
THIRD OF THE NATION.
REGARDING THE FORECAST DETAILS...A WELL DEFINED SHORT WAVE WILL
PASS JUST NORTH OF NEW YORK STATE ON WEDNESDAY...BEFORE DRIFTING
INTO NORTHERN NEW ENGLAND WEDNESDAY NIGHT. A TIGHT PRESSURE GRADIENT
BETWEEN THIS LOW AND HIGH PRESSURE OVER THE SOUTHEAST WILL AGAIN
MAKE FOR A BREEZY TO WINDY DAY ACROSS THE REGION. EXPECT WIND GUSTS
TO BE STRONGER WEDNESDAY THAN TUESDAY...WITH THE LOW CLOSER TO THE
REGION. A FEW GUSTS MAY APPROACH 40 TO 45 MPH IN TRADITIONALLY GUSTY
AREAS OF THE CWA.
A WEAK FRONT THAT IS ASSOCIATED WITH THIS IMPULSE WILL DROP SOUTH
ACROSS NEW YORK STATE WEDNESDAY NIGHT...BUT THE FRONT WILL NOT HAVE
MUCH MOISTURE TO WORK WITH. WILL HAVE LOW CHC POPS EAST OF LAKE
ONTARIO WHERE SOME LAKE ENHANCEMENT TO THE PRECIPITATION MIGHT
OCCUR. OTHERWISE EXPECT THE REGION TO REMAIN DRY.
ON THURSDAY...THE GFS AND ECMWF ARE IN BETTER AGREEMENT REGARDING
THE MOVEMENT OF THE CLOSED LOW THAT WILL BE LIFTING OUT OF THE
SOUTHERN PLAINS. THE GFS IS STILL A LITTLE FASTER IN LIFTING THE
UPPER LOW OUT...BUT THE GENERAL TREND IS THAT ANY PCPN ASSOCIATED
WITH THE APPROACHING LOW MAY DELAYED UNTIL THURSDAY NIGHT. THE
SLOWER MOVEMENT OF THE LOW ALSO MEANS THAT IT WILL TAKE LONGER THE
FOR BOUNDARY LAYER TEMPERATURES TO MODERATE. THIS MAY RESULT IN A
BETTER CHANCE FOR LIGHT SNOW AT THE ONSET OF THE PCPN.
ON FRIDAY...THE UPPER LOW WILL WEAKEN AS IT ENCOUNTERS THE FLAT
RIDGE THAT WILL STILL BE IN PLACE OVER THE EASTERN PART OF THE
NATION. BY SATURDAY...THE ECMWF TAKES THE ASSOCIATED SURFACE LOW AND
MERGES IT WITH A DEEPER LOW THAT WILL BE LIFTING NORTH ACROSS JAMES
BAY. SINCE THE SURFACE LOW IS FORECAST TO STAY TO OUR WEST...A MILD
SOUTHWEST FLOW WILL PREVAIL ACROSS THE AREA. THIS WILL LIKELY CAUSE
MOST PCPN TO FALL AS RAIN ON FRIDAY AND SATURDAY.
THE MODERATING TREND DURING THIS PERIOD WILL PUSH TEMPERATURES INTO
THE LOWER TO MID 40S ACROSS MOST OF THE AREA ON FRIDAY AND SATURDAY.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
EXPECT MAINLY MVFR CONDITIONS ACROSS WESTERN NY WITH WIDESPREAD
LIGHT/WET SNOW MIXED WITH RAIN AT TIMES. THERE MAY BE A FEW BRIEF
PERIODS OF IFR IN THE SOMEWHAT STEADIER SNOW. MVFR CIGS HAVE ALSO
SPREAD INTO MUCH OF THE AREA...AND THESE WILL CONTINUE THIS
AFTERNOON.
AFTER THIS...A FRONTAL BOUNDARY AND UPPER LEVEL TROF WILL BRING A
PERIOD OF SNOW TO MOST TAF LOCATIONS...WITH THIS LIKELY TO RESULT
VSBY OF 2SM OR LOWER...AND IFR CONDITIONS. THE LOWEST CONDITIONS
WILL BE AT JHW/ART...WITH LIGHTER SNOWFALL RATES EXPECTED AT
IAG/ROC. CONFIDENCE IN TIMING IS MODERATE...GIVEN GOOD MODEL
AGREEMENT IN THE PATTERN...HOWEVER IT IS POSSIBLE IFR CIGS MAY
BUILD IN AHEAD OF THE SNOW IN THE SOUTHWEST FLOW.
CIGS SHOULD MAINLY LIFT BEHIND THE FRONT...BUT MAY BRIEFLY LOWER
IMMEDIATELY PRECEDING THE FRONTAL PASSAGE DURING THE EVENING
HOURS. AFTER THIS...CLOUDS WILL PROBABLY SCATTER NEAR THE
LAKES...BUT PERSISTENT MVFR CIGS ARE MORE LIKELY INLAND.
OUTLOOK...
MONDAY AND TUESDAY...VFR.
WEDNESDAY...MAINLY VFR.
THURSDAY...VFR/MVFR WITH A CHANCE OF RAIN SHOWERS.
&&
.MARINE...
LOW PRESSURE ACROSS THE CENTRAL LAKES WILL LIFT UP THE SAINT
LAWRENCE VALLEY LATER TODAY. THIS WILL RESULT IN A DECENT SOUTHWEST
FLOW AND SMALL CRAFT CONDITIONS TODAY AND INTO TONIGHT. WINDS WILL
SHIFT TO THE NORTH AS AN ASSOCIATED COLD FRONT DROPS ACROSS THE
WATERS TONIGHT. THEN HIGH PRESSURE WILL BUILD ACROSS THE WATERS
MONDAY...WITH DIMINISHING WINDS. AS THE HIGH SLIDES EAST...A
TIGHTENING PRESSURE GRADIENT MAY REQUIRE SMALL CRAFT ADVISORIES
AGAIN MID-WEEK IN A SOUTHWESTERLY FLOW.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EST MONDAY FOR LEZ040-041.
SMALL CRAFT ADVISORY UNTIL 9 PM EST THIS EVENING FOR
LEZ020.
SMALL CRAFT ADVISORY UNTIL 10 AM EST MONDAY FOR
LOZ043-044.
SMALL CRAFT ADVISORY UNTIL 4 AM EST MONDAY FOR LOZ042-045.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL/HITCHCOCK
SHORT TERM...THOMAS
LONG TERM...THOMAS/TJP
AVIATION...APFFEL/HITCHCOCK
MARINE...APFFEL/THOMAS
AREA FORECAST DISCUSSION
NWS BUFFALO NY
741 AM EST SUN JAN 6 2013
.SYNOPSIS...
A WEAK AREA OF LOW PRESSURE WILL BRING MINOR SNOW ACCUMULATIONS TO
MOST LOCATIONS THIS AFTERNOON AND EVENING...BUT SNOWS WILL BE
A BIT STEADIER EAST OF LAKE ONTARIO. HIGH PRESSURE WILL THEN BUILD
INTO THE OHIO VALLEY AND EASTERN GREAT LAKES FOR THE FIRST HALF OF
NEXT WEEK WITH DRY WEATHER AND WARMING TEMPERATURES. THE JANUARY
THAW WILL LAST RIGHT THROUGH NEXT WEEKEND WITH MILD TEMPERATURES AND
INCREASING CHANCES OF RAIN.
&&
.NEAR TERM /THROUGH TONIGHT/...
A SHORTWAVE EXITING TO THE EAST HAS LEFT WESTERN NEW YORK IN NO
MANS LAND OF SORT. THERE ARE SOME LIGHT LAKE ENHANCED RAIN AND
SNOW SHOWERS NORTHEAST OF LAKE ERIE...OTHERWISE THE MAJORITY OF
THE REGION IS DRY. THIS PATTERN SHOULD CONTINUE THROUGH THE
MORNING HOURS. THE FINGER LAKES AND GENESEE VALLEY MAY GET SOME
BREAKS OF SUN...WHICH WOULD HELP TEMPERATURES WARM A BIT. EXPECT
HIGHS IN THE UPPER 30S IN MOST LOCATIONS...WITH LOWER 40S IN SPOTS
WHICH GET SOME SUN.
THE MORE SIGNIFICANT PART OF THIS GENERALLY WEAK SYSTEM WILL IMPACT
THE REGION DURING THE AFTERNOON AND EVENING HOURS. THE KEY WILL
BE THE PASSAGE OF A SHORT WAVE...WHICH WILL HELP DRIVE A COLD
FRONT ACROSS THE REGION. HOWEVER...THERE WILL BE WELL ALIGNED
SOUTHWEST FLOW AHEAD OF THIS...WITH AMPLE MOISTURE AND A LONG
FETCH. 850 MB TEMPERATURES WILL ONLY BE AROUND -7C...WITH LAKE
INDUCED CAPES BARELY MEASURABLE. HOWEVER...THIS WILL PROBABLY BE
ENOUGH TO BOOST MOISTURE A BIT...AND BRING A PERIOD OF SNOW TO
MOST LOCATIONS. THE QPF FORECAST OF MOST OF THE HIGHER RESOLUTION
MODEL GUIDANCE SUGGESTS THIS ENHANCEMENT WILL BE A SIGNIFICANT
PART OF WHATEVER SNOW FALLS...AND SEVERAL RUNS OF THE HRRR ARE
PRODUCING PLAUSIBLE SOLUTIONS.
THE LIONS SHARE OF SNOW WILL FALL BETWEEN 18Z AND 06Z...WITH MOST
LOCATIONS LIKELY TO SEE ONLY A FEW HOURS OF LIGHT TO MODERATE
SNOWS SOMEWHERE IN THAT TIMEFRAME. EXPECT AN INCH OR TWO TO FALL EAST
OF LAKE ERIE. STEADIER SNOWS WILL FALL EAST OF LAKE ONTARIO...WITH
STEADIER SNOWS LIKELY TO DEVELOP THIS AFTERNOON...AND CONTINUE
INTO THE EVENING. HRRR GUIDANCE SUGGESTS A BAND OF MODERATE SNOW
WILL DEVELOP...WITH A TOTAL OF 2 TO 4 INCHES OF SNOW LIKELY IN
THAT REGION THIS AFTERNOON AND EVENING. THIS IS IN LINE WITH THE
SEVERAL RUNS OF THE RGEM/NAM. THE EASTERN LAKE ONTARIO
REGION...WITH THE SOUTHWEST FLOW...AND MODEL QPF FORECASTS
SUGGESTING THIS FORECAST WILL APPLY TO THE CITY OF WATERTOWN AND
ALL OF JEFFERSON COUNTY. WILL HAVE TO WATCH THIS POTENTIAL
BAND...WITH THE POSSIBILITY THAT AN ADVISORY WILL BE REQUIRED. ONE
LIMITING FACTOR MAY BE TEMPERATURES...WHICH WILL BE NEAR OR ABOVE
FREEZING THROUGH THE EVENT. LESSER AMOUNTS WILL FALL FURTHER FROM
THE LAKE IN ROCHESTER...GENESEE VALLEY...AND FINGER LAKES REGIONS.
THE FRONT WILL PUSH SOUTH OF THE REGION LATE TONIGHT...WHICH SHOULD
BRING DRIER AIR INTO THE REGION. SOME LIGHT LAKE EFFECT SNOW SHOWERS
OR FLURRIES CAN/T BE RULED OUT...BUT WHAT DOES DEVELOP SHOULD BE
SHORT LIVED GIVEN THE SHORT FETCH IN THE NORTHERLY FLOW AND THE DRY
AIR UPSTREAM. HOWEVER...THIS SET UP IS FAVORABLE FOR CLOUDS TO BE
QUITE PERSISTENT BEHIND THE FRONT...AS ANY LAKE MOISTURE GETS
TRAPPED BENEATH THE INVERSION. BECAUSE OF THIS...HEDGE ON THE WARM
SIDE OF GUIDANCE FOR LOW TEMPERATURES. EXPECT LOWS IN THE LOWER 20S
IN MOST LOCATIONS...BUT SIGNIFICANTLY COOLER TEMPERATURES ARE
POSSIBLE EAST OF LAKE ONTARIO WHERE CLEARING IS POSSIBLE.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
A QUIET PERIOD IS EXPECTED MONDAY AND TUESDAY WITH A SLOW MODERATING
TREND TO CONTINUE THROUGH THE WORK WEEK.
FOR MONDAY A FEW FLURRIES OR LIGHT SNOW SHOWERS MAY STILL BE FALLING
OFF LAKE ONTARIO SOUTHEAST OF THE LAKE EARLY IN THE MORNING HOURS.
TEMPERATURES ALOFT AT 850 HPA UNDER WARM AIR ADVECTION ARE ONLY
MARGINAL FOR LAKE EFFECT SNOW...AND WITH LOW LEVEL LIFT ESSENTIALLY
GONE AND MOISTURE LACKING FROM WITHIN THE SNOW GROWTH ZONE...ANY
SUPPORT FOR LAKE EFFECT SNOW WILL NOT BE CONDUCIVE...THUS ANY LAKE
ACTIVITY SHOULD DIMINISH QUICKLY THROUGH THE MORNING. THE 850 HPA
RIDGE REMAINS TO OUR WEST TO START THE DAY AND A BROKEN LOW LAYER OF
CLOUDS ACROSS HIGHER TERRAIN OF WNY...GENESEE VALLEY AND NORTHERN
FINGER LAKES REGION WILL LIKELY START THE DAY. AS THIS RIDGE AXIS
PASSES THE AREA FROM WEST TO EAST THROUGH THE MORNING HOURS EXPECT
INCREASING AMOUNTS OF SUNSHINE. DESPITE A GOOD DEAL OF SUNSHINE
THROUGH THE AFTERNOON HOURS TEMPERATURES WILL HOLD TO AROUND NORMAL
ACROSS WESTERN NEW YORK...WITH HIGHS AROUND 30...AND SLIGHTLY BELOW
NORMAL ACROSS THE EASTERN LAKE ONTARIO REGION WITH LOW TO MID
20S.
MONDAY NIGHT A BROAD AREA OF HIGH PRESSURE WILL BE FOUND ALONG THE
ATLANTIC COASTLINE WITH A SOUTHWEST RETURN FLOW ACROSS THE EASTERN
GREAT LAKES REGION. THIS WILL PROHIBIT TEMPERATURES FROM
PLUNGING...AND IN FACT THEY MAY RISE A DEGREE OR TWO OVERNIGHT
ACROSS THE DOWN SLOPE AREAS OF WNY. TOWARDS THE NORTHERN FINGER
LAKES AND EASTERN LAKE ONTARIO REGION WHERE THE SOUTHWEST FLOW WILL
NOT BE AS GREAT TEMPERATURES WILL FALL BACK INTO THE TEENS TO AROUND
20. TO THE WEST MILDER OVERNIGHT LOWS ARE EXPECTED...WITH LOW 20S
ACROSS INTERIOR SOUTHWEST NEW YORK AND UPPER 20S FOR THE LOWER
ELEVATIONS.
LATE MONDAY NIGHT AND TUESDAY A STORM SYSTEM WILL PASS WELL TO OUR
NORTH ACROSS JAMES BAY AND CENTRAL/NORTHERN QUEBEC. A TIGHTENING
PRESSURE GRADIENT BETWEEN THIS SYSTEM AND HIGH PRESSURE ALONG THE
EASTERN SHORELINE WILL ALLOW WINDS TO BECOME BREEZY THROUGH THE DAY
TUESDAY...ESPECIALLY OFF THE LAKES ON A SOUTHWEST FLOW. A FEW CLOUDS
WILL LIKELY PASS ACROSS THE REGION THOUGH STILL A GOOD DEAL OF
SUNSHINE IS EXPECTED. TEMPERATURES ALOFT AT 850 HPA WILL BE SEVERAL
DEGREES WARMER THAN MONDAY...AND WITH THESE SOUTHWEST WINDS
TEMPERATURES SHOULD BE A BIT WARMER THAN MONDAY...WITH HIGHS
MODERATING INTO THE MID TO UPPER 30S. REMAINING DRY OVERNIGHT THOUGH
CLOUDS WILL START TO THICKEN MORE AS A SECOND STORM SYSTEM TAKES A
SLIGHTLY MORE SOUTHERN TRACK THROUGH CANADA. LOWS TUESDAY NIGHT WILL
FALL BACK INTO THE MID 20S TO AROUND 30 ACROSS THE REGION.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
A GENERAL ZONAL FLOW WILL REMAIN IN PLACE ALONG THE CANADIAN/U.S.
BORDER THROUGH THURSDAY. AFTER THAT...A MORE AMPLIFIED FLOW WILL SET
UP THURSDAY NIGHT THROUGH SATURDAY AS A DEEPENING TROUGH DIGS INTO
THE WESTERN U.S...WHILE A FLAT RIDGE REMAINS IN PLACE OVER EASTERN
THIRD OF THE NATION.
REGARDING THE FORECAST DETAILS...A WELL DEFINED SHORT WAVE WILL
PASS JUST NORTH OF NEW YORK STATE ON WEDNESDAY...BEFORE DRIFTING
INTO NORTHERN NEW ENGLAND WEDNESDAY NIGHT. A TIGHT PRESSURE GRADIENT
BETWEEN THIS LOW AND HIGH PRESSURE OVER THE SOUTHEAST WILL AGAIN
MAKE FOR A BREEZY TO WINDY DAY ACROSS THE REGION. EXPECT WIND GUSTS
TO BE STRONGER WEDNESDAY THAN TUESDAY...WITH THE LOW CLOSER TO THE
REGION. A FEW GUSTS MAY APPROACH 40 TO 45 MPH IN TRADITIONALLY GUSTY
AREAS OF THE CWA.
A WEAK FRONT THAT IS ASSOCIATED WITH THIS IMPULSE WILL DROP SOUTH
ACROSS NEW YORK STATE WEDNESDAY NIGHT...BUT THE FRONT WILL NOT HAVE
MUCH MOISTURE TO WORK WITH. WILL HAVE LOW CHC POPS EAST OF LAKE
ONTARIO WHERE SOME LAKE ENHANCEMENT TO THE PRECIPITATION MIGHT
OCCUR. OTHERWISE EXPECT THE REGION TO REMAIN DRY.
ON THURSDAY...THE GFS AND ECMWF ARE IN BETTER AGREEMENT REGARDING
THE MOVEMENT OF THE CLOSED LOW THAT WILL BE LIFTING OUT OF THE
SOUTHERN PLAINS. THE GFS IS STILL A LITTLE FASTER IN LIFTING THE
UPPER LOW OUT...BUT THE GENERAL TREND IS THAT ANY PCPN ASSOCIATED
WITH THE APPROACHING LOW MAY DELAYED UNTIL THURSDAY NIGHT. THE
SLOWER MOVEMENT OF THE LOW ALSO MEANS THAT IT WILL TAKE LONGER THE
FOR BOUNDARY LAYER TEMPERATURES TO MODERATE. THIS MAY RESULT IN A
BETTER CHANCE FOR LIGHT SNOW AT THE ONSET OF THE PCPN.
ON FRIDAY...THE UPPER LOW WILL WEAKEN AS IT ENCOUNTERS THE FLAT
RIDGE THAT WILL STILL BE IN PLACE OVER THE EASTERN PART OF THE
NATION. BY SATURDAY...THE ECMWF TAKES THE ASSOCIATED SURFACE LOW AND
MERGES IT WITH A DEEPER LOW THAT WILL BE LIFTING NORTH ACROSS JAMES
BAY. SINCE THE SURFACE LOW IS FORECAST TO STAY TO OUR WEST...A MILD
SOUTHWEST FLOW WILL PREVAIL ACROSS THE AREA. THIS WILL LIKELY CAUSE
MOST PCPN TO FALL AS RAIN ON FRIDAY AND SATURDAY.
THE MODERATING TREND DURING THIS PERIOD WILL PUSH TEMPERATURES INTO
THE LOWER TO MID 40S ACROSS MOST OF THE AREA ON FRIDAY AND SATURDAY.
&&
.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
EXPECT MAINLY MVFR CONDITIONS DUE TO CEILINGS THROUGH THIS MORNING
AS AN INITIAL DISTURBANCE EXITS TO THE EAST. BRIEF BREAKS TO VFR
ARE POSSIBLE...IN AND OUT OF SUBTLE WAVES OF MOISTURE.
AFTER THIS...A FRONTAL BOUNDARY AND UPPER LEVEL TROF WILL BRING A
PERIOD OF SNOW TO MOST TAF LOCATIONS...WITH THIS LIKELY TO RESULT
VSBY OF 2SM OR LOWER...AND IFR CONDITIONS. THE LOWEST CONDITIONS
WILL BE AT JHW/ART...WITH LIGHTER SNOWFALL RATES EXPECTED AT
IAG/ROC. CONFIDENCE IN TIMING IS MODERATE...GIVEN GOOD MODEL
AGREEMENT IN THE PATTERN...HOWEVER IT IS POSSIBLE IFR CIGS MAY
BUILD IN AHEAD OF THE SNOW IN THE SOUTHWEST FLOW.
CIGS SHOULD MAINLY LIFT BEHIND THE FRONT...BUT MAY BRIEFLY LOWER
IMMEDIATELY PRECEDING THE FRONTAL PASSAGE DURING THE EVENING
HOURS. AFTER THIS...CLOUDS WILL PROBABLY SCATTER NEAR THE
LAKES...BUT PERSISTENT MVFR CIGS ARE MORE LIKELY INLAND.
OUTLOOK...
MONDAY AND TUESDAY...VFR.
WEDNESDAY...MAINLY VFR.
THURSDAY...VFR/MVFR WITH A CHANCE OF RAIN SHOWERS.
&&
.MARINE...
LOW PRESSURE ACROSS THE CENTRAL LAKES WILL LIFT UP THE SAINT
LAWRENCE VALLEY LATER TODAY. THIS WILL RESULT IN A DECENT SOUTHWEST
FLOW AND SMALL CRAFT CONDITIONS TODAY AND INTO TONIGHT. WINDS WILL
SHIFT TO THE NORTH AS AN ASSOCIATED COLD FRONT DROPS ACROSS THE
WATERS TONIGHT. THEN HIGH PRESSURE WILL BUILD ACROSS THE WATERS
MONDAY...WITH DIMINISHING WINDS. AS THE HIGH SLIDES EAST...A
TIGHTENING PRESSURE GRADIENT MAY REQUIRE SMALL CRAFT ADVISORIES
AGAIN MID-WEEK IN A SOUTHWESTERLY FLOW.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EST MONDAY FOR LEZ040-041.
SMALL CRAFT ADVISORY UNTIL 9 PM EST THIS EVENING FOR
LEZ020.
SMALL CRAFT ADVISORY UNTIL 10 AM EST MONDAY FOR
LOZ043-044.
SMALL CRAFT ADVISORY UNTIL 4 AM EST MONDAY FOR LOZ042-045.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...THOMAS
LONG TERM...THOMAS/TJP
AVIATION...APFFEL
MARINE...APFFEL/THOMAS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1055 AM EST SUN JAN 6 2013
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL CROSS THE THE MIDDLE ATLANTIC STATES
TODAY...FOLLOWED BY THE PASSAGE OF A DRY COLD FRONT TONIGHT. HIGH
PRESSURE WILL BUILD INTO...AND REMAIN OVER OUR REGION...THROUGH
TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1055 AM SUNDAY...
AN AREA OF OF LIGHT RAIN FALLING FROM CEILINGS IN THE 3-6KFT RANGE
ACROSS THE SOUTHEASTERN HALF OF THE RAH CWA WILL SHIFT EAST DURING
THE NEXT FEW HOURS. THE KGSO RAOB THIS MORNING WAS NOTABLY DRIER AND
WARMER IN THE LOWEST ~5KFT COMPARED TO RECENT NAM/GFS FCST BUFR
SOUNDINGS AND NOTED MULTIPLE LAYERS OF DRYING ALOFT. RECENT VIS SAT
IMAGES HAVE INDICATED SOME EASTWARD ADVANCEMENT OF THE AREA OF
THINNING CLOUDS IN THE FOOTHILLS WHILE THE REMAINDER OF THE RAH CWA
IS BLANKETED IN OVERCAST SKIES.
EXPECT MOSTLY CLOUDY/CLOUDY SKIES TO PERSIST FOR THE REMAINDER OF
THE DAY WITH AREAS OF VERY LIGHT PRECIPITATION ACROSS THE
SOUTHERN/SOUTHEAST TIER. AFTER THE INITIAL AREA OF RAIN OVER THE
AREA WANES FOR A FEW HOURS AROUND/JUST AFTER MIDDAY...ANOTHER AREA
OF PATCHY LIGHT RAIN IS EXPECTED TO DEVELOP ACROSS SC AND SPREAD
INTO THE FAR SOUTHERN PIEDMONT..THE SOUTHERN SANDHILLS AND THE
SOUTHERN COASTAL PLAIN. THIS AREA OF RAIN IS EXPECTED TO BE
GENERATED THROUGH LOW LEVEL MOISTURE ADVECTION AND SHALLOW LIFT WITH
THE GFS AND TO A LESSER EXTENT THE NAM INDICATING SOME LIGHT QPF.
THE HIGH RES CONVECTION ALLOWING MODELS...ESPECIALLY THE HRRR HAVE
BEEN BULLISH ON ANOTHER SURGE OF PRECIPITATION BUT THE PAST RUN OR
TWO HAVE BACKED OFF A BIT. WOULD NOT CATEGORIZE THE DAY AS A WASHOUT
AS QPF VALUES WILL ONLY BE ON THE ORDER OF A FEW HUNDREDTHS OF AN
INCH. TEMPERATURES WILL BE MODULATED A GREAT DEAL BY THE CLOUDS AND
PRECIPITATION WITH HIGHS IN THE LOWER 50S ACROSS THE WEST/NORTHWEST
PARTS OF FORECAST AREA TO THE UPPER 40S/NEAR 50 EAST. -BLAES
TONIGHT: A POTENT NORTHERN STREAM S/W TROUGH AND ASSOCIATED SURFACE
COLD FRONT WILL SWEEP EASTWARD ACROSS CENTRAL NC. A RENEWED AREA OF
MID CLOUDS...AND LINGERING JET CIRRUS MAY ACCOMPANY THE S/W THROUGH
06Z...BUT STRONG SUBSIDENCE AND RAPID CLEARING/DRYING WILL COMMENCE
THEREAFTER. POST-FRONTAL...CAA-DRIVEN LOWS IN THE UPPER 20S TO
LOWER-MIDDLE 30S. -MWS
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
AS OF 320 AM SUNDAY...
MODIFIED CONTINENTAL POLAR HIGH PRESSURE WILL BUILD ACROSS AND
LINGER OVER THE MIDDLE ATLANTIC AND CAROLINAS THIS PERIOD...
ASSOCIATED NORTHEASTERLY FLOW DURING THE DAY...AND NIGHTTIME
CALM...WILL RESULT IN BELOW AVERAGE TEMPERATURES IN THE UPPER 40S TO
AROUND 50 AND UPPER 20S...RESPECTIVELY...THE LATTER OF WHICH SHOULD
OCCUR DESPITE INCREASING CIRRUS OVERNIGHT.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 258 AM SUNDAY...
MODEL SOLUTIONS COMING TOGETHER WITH THE TRACK OF THE LOW LATE IN
THE WEEK... MOVING FROM TX ON THURS INTO THE GREAT LAKES FRI. GFS
AND ECMWF STILL SHOWING THE TAIL END OF A NORTHERN STREAM COLD FRONT
ENTERING THE REGION ON THURSDAY... WITH BACKED WINDS BRIEFLY
INDICATED ON FORECAST SOUNDINGS... BEFORE A WARM FRONT SURGES NORTH
ON FRIDAY. THE ASSOCIATED COLD FRONT WILL JUST ENTER THE REGION
OVERNIGHT FRIDAY INTO SATURDAY... BEFORE WASHING OUT. TEMPS WILL BE
HIGHLY DEPENDENT ON THE TIMING AND MOVEMENT OF THESE FRONTAL ZONES
IN THE LATTER PART OF THE WEEK... BUT WILL CONTINUE TO KEEP HIGHS IN
THE 60S... WITH LOWS IN THE 40S. PRECIPITATION DOES NOT APPROACH THE
AREA UNTIL LATER IN THE DAY ON THURSDAY... AND LINGERS THROUGH
FRIDAY.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 650 AM SUNDAY...
PERIODS OF LIGHT RAIN OR SPRINKLES WILL CONTINUE MAINLY EAST OF KRDU
(IE. AT KRWI AND KFAY) THROUGH AROUND SUNSET. A PERIOD OF MVFR
CEILINGS WILL LIKELY ACCOMPANY THE THIS LIGHT PRECIPITATION DURING
THE AFTERNOON...PARTICULARLY AT KFAY. A DRY COLD FRONT AND
ASSOCIATED TRAILING CLEAR SKIES AND SURFACE WIND SHIFT TO
NORTHWESTERLY WILL SWEEP EASTWARD ACROSS CENTRAL NC BETWEEN 03-09Z.
OUTLOOK: RETURN SOUTHWESTERLY FLOW WILL PROMOTE AN INCREASING
LIKELIHOOD OF SUB-VFR CEILINGS AT KFAY TUE AFT...AND ACROSS THE
REMAINDER OF CENTRAL NC TERMINALS TUE NIGHT. SUB-VFR CONDITIONS AND
A CHANCE OF SHOWERS WILL THEN RETURN FOR LATE THU.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MWS
NEAR TERM...BLAES/MWS
SHORT TERM...MWS
LONG TERM...SEC
AVIATION...MWS
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
940 AM EST SUN JAN 6 2013
.DISCUSSION...
CURRENT...FOG AND LOW CLOUDS WERE LIFTING ALONG THE COAST WHILE
INLAND FOG AND/OR LOW CLOUDS WERE STILL A PROBLEM. EXPECT THAT THE
FOG AND LOW CLOUDS OVER THE INTERIOR WILL HAVE LIFTED BETWEEN
10AM/15Z AND 11AM/16Z. THIS MATCHES WELL WITH THE 10AM EXPIRATION OF
THE DENSE FOG ADVISORY.
THE WEST PALM BEACH AIRPORT RADAR WAS DETECTING SHOWERS MOVING SOUTH
TO NORTH ALONG THE IMMEDIATE MARTIN AND SAINT LUCIE COAST WEST TO
INTERSTATE 95.
LATEST RUC40 GUIDANCE RUN WAS SHOWING LITTLE MID LEVEL SUPPORT FOR
ANYTHING MORE THAN ISOLATED SHOWERS THIS MORNING AND EARLY
AFTERNOON. WENT WITH THAT SUGGESTION AND AMENDED THE WEATHER GRID
OUT TO 2PM/19Z TO REFLECT ISOLATED SHOWERS TO MID AFTERNOON THEN
START THE MORE SIGNIFICANT WEATHER MID TO LATE AFTERNOON.
SAME RUC RUN ALSO INDICATING THAT THE BEST ISENTROPIC LIFT SHOULD
START DURING THE AFTERNOON WITH THE STATIONARY BOUNDARY HAVING
STARTED MOVING AGAIN AS A WARM FRONTAL BOUNDARY.
&&
.AVIATION...VFR THROUGH LATE AFTERNOON. PREVAILING MVFR CEILINGS
LATE AFTERNOON AND OVERNIGHT AS LIGHT RAIN IS EXPECTED TO START.
&&
.MARINE...
CURRENT...THE NOAA BUOYS WERE RECORDING LIGHT WINDS FROM THE
NORTHEAST TO THE SOUTHEAST AND 3 FOOT SEAS. THE TWO SCRIPPS BUOYS
WERE RECORDING 2 FOOT SEAS.
THIS AFTERNOON...WINDS SHOULD REMAIN LIGHT WITH THE FRONTAL BOUNDARY
IN THE AREA. ISOLATED SHOWERS SOUTH OF FORT PIERCE INLET THIS
MORNING AND EARLY AFTERNOON. SHOWERS...SLIGHT CHANCE OF A LIGHTNING
STORM THIS AFTERNOON AND EVENING.
PREVIOUS MARINE DISCUSSION
TODAY-TONIGHT...WEAK FRONTAL BOUNDARY LIFTING NORTH OVER
WATERS THIS MORNING...CURRENTLY LOCATED AROUND CAPE CANAVERAL. WINDS
WILL BE SOUTH-SOUTHEAST AT 10-15KTS SOUTH OF THE BOUNDARY AND E-NE
5KTS NORTH OF THE BOUNDARY. BOUNDARY IS EXPECTED TO STALL OVER THE
VOLUSIA COUNTY WATERS THIS AFTERNOON...BEFORE GETTING PUSHED BACK
TO THE SOUTH OVERNIGHT. WINDS WILL TURN N-NW BEHIND THE RETREATING
FRONT...WITH A WIND SURGE INCREASING SPEEDS TO 15-20KTS TOWARDS
DAYBREAK MONDAY. SEAS 2-3FT UNDER CHOPPY 5-6SEC PERIODS. PRESENCE OF
THE BOUNDARY WILL LEAD TO SCT-NMRS SHOWERS THROUGH THE PERIOD WITH
ISOLD TSTMS POSSIBLE THIS AFTERNOON AND OVERNIGHT...MAINLY OVER THE
WARMER GULF STREAM WATERS.
MON-THU...POST FRONTAL NE-E SURGE A LITTLE LESS ROBUST THAN EARLIER
PROGGED...WITH WINDS/SEAS NOW FCST TO REMAIN A LITTLE BELOW SCA CUSP
OF 20KT/7FT FOR THE NORTHERN HALF CWA THROUGH MONDAY EVENING...SO IT
SEEMS CAUTIONARY STMT NORTH OF SEBASTIAN MAY BE MORE LIKELY SCENARIO
FOR MON-MON EVENING. WINDS/SEAS GENERALLY STAY IN THE 12-18KT AND
3-5FT RANGE AS THE LOW LEVEL FLOW VEERS FROM E TO SE BY MID-LATE
WEEK.
&&
FPR 80 61 76 64 / 20 60 30 30
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
UPDATES/AVIATION...WIMMER
IMPACT WX/RADAR....KELLY