Forecast Discussions mentioning any of
"HRRR" "RR" "RUC13" "RUC" received at GSD on 01/08/12
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND JUNCTION CO
548 PM MST SAT JAN 7 2012
.UPDATE...
CONTINUING TO PULL BACK THE WINTER WEATHER HIGHLIGHTS BASED ON
LATEST SURFACE OBS AND SPOTTER REPORTS. HAVE NOW CANCELLED THE
NORTHWEST PLATEAU IN NORTHWEST COLORADO AS SNOW HAS ENDED AT CRAIG
AND MEEKER AND CEILINGS CONTINUE TO LIFT. RADAR RETURNS SUPPORT
HIGHLIGHTS OVER THE CENTRAL ZONES...JUST AHEAD OF THE UPPER LEVEL
TROUGH THAT IS SAGGING THROUGH THE FORECAST AREA...SO NO OTHER
ADJUSTMENTS PLANNED AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 448 PM MST SAT JAN 7 2012/...
UPDATE...
SNOWFALL COMING TO A RAPID END ACROSS THE EASTERN UINTA MOUNTAINS
LATE THIS AFTERNOON BASED ON CURRENT WEB CAMS IN THE REGION. AS A
RESULT...HAVE DROPPED THE WINTER WEATHER ADVISORY FOR THIS AREA
AND ADJUSTED THE CHANCE OF PRECIPITATION FOR THE REMAINDER OF THIS
EVENING. BASED ON CURRENT TRACK AND SPEED OF THE UPPER LEVEL
LOW...ADDITIONAL ADJUSTMENTS MAY BE NEED TO CURRENT WINTER
HIGHLIGHTS. WILL CONTINUE TO MONITOR.
&&
.PREV DISCUSSION... /ISSUED 305 PM MST SAT JAN 7 2012/
.SHORT TERM /TONIGHT THROUGH MONDAY/...
LATEST MOSAIC IMAGERY SHOWING LARGE BAND OF SNOW MOVING ACROSS
BOOKCLIFFS THEN EASTWARD ALONG INTERSTATE 70 TOWARDS GLENWOOD
SPRINGS AND EAGLE. CDOT WEBCAMS ALSO SHOWING PLENTY OF SNOW ALONG
THE CORRIDOR. CROSS-SECTIONS INDICATE RATHER LARGE AREA OF
CONDITIONAL SYMMETRIC INSTABILITY MATCHING UP WITH THIS BAND WHICH
WOULD EXPLAIN THE RAPID SNOW ACCUMULATIONS AT THE SFC DUE TO SOME
SLANTWISE CONVECTION. IF THE BAND STAYS TOGETHER AND CONTINUES TO
DROP SWRD...SOME QUICK ACCUMULATIONS ARE POSSIBLE OVER GRASSY
SURFACES OVER GRAND VALLEY AND AREAS SOUTH. HAVING SAID THAT...MODELS
DO KEEP THIS BAND TO OUR NORTH WITH SOME SLOW SWRD DRIFT THROUGH
THE AFTN AND EVENING. NORTH OF THIS AREA...SNOW CONTINUES TO FALL
OVER AND NEAR CRAIG...HAYDEN AND MEEKER. HILITES APPEAR TO BE ON
TRACK WITH SOME CONCERN REMAINING FOR THE UNCOMPAHGRE PLATEAU AND
NRN SAN JUANS AS RUC AND HRRR SHOW SOME DEVELOPMENT OVER THAT
AREA. OF COURSE...18Z NAM SHOWS SOME PRECIP BUT NOT ENOUGH TO
WARRANT ANY ADVISORIES. WILL NOT PULL THE TRIGGER YET BUT WILL
KEEP AN EYE ON WEBCAMS...RADAR...SATELLITE AND LOCAL SNOW REPORTS.
SFC COLD FRONT MOVED THROUGH AREA QUICKER THAN EXPECTED AND IS
CLEARLY SEEN ON WATER VAPOR AND IR IMAGERY MOVING OVR SERN CO AND
NRN NM. THE UPPER LEVEL TROF AND UPPER LOW REMAIN OVER NERN UT
ATTM AND ARE STILL EXPECTED TO MOVE OVER THE REGION THIS AFTN INTO
TONIGHT CAUSING MORE SNOWFALL. THUS...MADE LITTLE TO NO CHANGE FOR
OVERNIGHT FORECAST. SINCE SPEED OF SYSTEM HAS INCREASED
SOMEWHAT...AGREE WITH PREVIOUS THINKING THAT HILITES MAY HAVE TO
BE TAKEN DOWN EARLY PROBABLY NEARER TO EARLY SUNDAY MORNING. WILL
LEAVE AS IS FOR NOW.
BY SUNDAY...MOSTLY SUNNY SKIES FOR AREAS N AND CLEARING SKIES FOR
THE SOUTH. TEMPS WILL RUN NEAR NORMAL FOR THIS TIME OF YEAR...OR
ABOUT 10 DEGREES COOLER THAN SEEN THIS PREVIOUS WEEK. HIGH
PRESSURE WILL BUILD IN AND PERSIST THROUGH MID-WEEK.
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/
EASTERN UTAH AND WESTERN COLORADO WILL BE UNDER THE INFLUENCE OF AN
UPPER RIDGE MONDAY NIGHT AND TUESDAY...SQUEEZED BETWEEN A WRAPPED UP
SOUTHERN PLAINS LOW AND THE NEXT TROF ARRIVING OUT OF THE NORTHEAST
PACIFIC. AS SUCH THE DRY WEATHER WILL CONTINUE OVER THIS PERIOD WITH
THE WARMING ALOFT HELPING TO ENFORCE THE LOW LEVEL
INVERSIONS...ESPECIALLY IN AREAS WITH THE NEWER SNOW COVER AND DID
DIRECT TEMPERATURES TOWARD THE LOWER END OF GUIDANCE. BEYOND THIS
PERIOD CONFIDENCE CONTINUES TO WANE WITH DIFFERING MED RANGE MODEL
SOLUTIONS RELATED TO PROGRESSION OF THE WESTERN TROF. THE
DIFFERENCES ARE MOSTLY CENTERED AROUND THE EVOLUTION OF AN UPPER LOW
OVER THE SOUTHWEST CORNER OF THE CONUS AS ENERGY IN THE TROF SPLITS.
THE OPERATIONAL GFS SOLUTION IS SLOWER TO ACHIEVE THIS SPLIT WHICH
CONFLICTS WITH SOME OF IT/S MEMBERS AND WITH A REFLECTION OF A LOW
OFF THE SOCAL COAST IN THE H5 MEAN SOLUTION. THIS SLOWER SOLUTION
WOULD BE A WETTER SOLUTION AND IMPACT MORE OF THE CWA. FOR NOW
FORECAST CONTINUES TO LEAN AWAY FROM THIS TOWARD THE EURO WITH A
MORE NORTHERLY FLOW DOMINATING TUESDAY NIGHT INTO WEDNESDAY AS A
CLIPPER TYPE SYSTEM DROPS THROUGH THE NORTHERN PLAINS. THIS WOULD
BRING SOME OROGRAPHICS AND WEAK DYNAMICS TO THE CENTRAL AND NORTHERN
MOUNTAINS FOR A SLIGHT CHANCE OF SNOW. BEHIND THIS REX BLOCK SETS UP
IN THE WEST WITH DRY AND ABOVE NORMAL TEMPERATURES RETURNING TO THE
CWA FOR THE LAST HALF OF THE WEEK.
&&
.AVIATION /FOR 00Z TAF ISSUANCE/...
CONVECTIVELY DRIVEN SNOW CONTINUES ACROSS THE CENTRAL CWA...AND WILL
BE DROPPING SLOWLY SOUTH THROUGH THE EVENING AS THE MAIN SYSTEM
DROPS SOUTH OF THE GREAT BASIN. MVFR TO IFR FLIGHT CATEGORIES
CONTINUE ACROSS MUCH OF THE UPPER COLORADO RIVER BASIN INCLUDING THE
EGE AND RIL TERMINALS WHERE MODERATE SNOW BANDING PERSISTS. SLIGHT
IMPROVEMENT TO MORE WIDESPREAD MVFR AND POCKETS OF VFR IS EXPECTED
THROUGH THE EVENING HOURS AS THE MAIN DYNAMICS OF THE STORM SHIFT
SOUTH. KASE WILL EXPERIENCE LIFR/IFR CONDITIONS IN A FAVORABLE
NORTHWEST FLOW THIS EVENING WITH IMPROVEMENT EXPECTED AFTER
MIDNIGHT. MOUNTAIN OBSCURATION CAN BE EXPECTED TO PERSIST AS WELL
THROUGH THE EARLY MORNING HOURS. THE LOWER VALLEY TERMINALS OF MTJ
AND GJT LOOK TO PREVAIL AT VFR CONDITIONS THROUGH MUCH OF THIS STORM
PASSAGE...BUT TEMPORARY MVFR CONDITIONS COULD BE REALIZED AROUND THE
07/22Z-08/02Z TIME FRAME WHEN LIFT LOOKS TO BE ENHANCED OVER THIS
AREA.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL NOON MST SUNDAY FOR ZONES 003>005-
007>010-012-013.
UT...NONE.
&&
$$
UPDATE.......JDC
SHORT TERM...TGR
LONG TERM....15
AVIATION.....15
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND JUNCTION CO
448 PM MST SAT JAN 7 2012
.UPDATE...
SNOWFALL COMING TO A RAPID END ACROSS THE EASTERN UINTA MOUNTAINS
LATE THIS AFTERNOON BASED ON CURRENT WEB CAMS IN THE REGION. AS A
RESULT...HAVE DROPPED THE WINTER WEATHER ADVISORY FOR THIS AREA
AND ADJUSTED THE CHANCE OF PRECIPITATION FOR THE REMAINDER OF THIS
EVENING. BASED ON CURRENT TRACK AND SPEED OF THE UPPER LEVEL
LOW...ADDITIONAL ADJUSTMENTS MAY BE NEED TO CURRENT WINTER
HIGHLIGHTS. WILL CONTINUE TO MONITOR.
&&
.PREV DISCUSSION... /ISSUED 305 PM MST SAT JAN 7 2012/
.SHORT TERM /TONIGHT THROUGH MONDAY/...
LATEST MOSAIC IMAGERY SHOWING LARGE BAND OF SNOW MOVING ACROSS
BOOKCLIFFS THEN EASTWARD ALONG INTERSTATE 70 TOWARDS GLENWOOD
SPRINGS AND EAGLE. CDOT WEBCAMS ALSO SHOWING PLENTY OF SNOW ALONG
THE CORRIDOR. CROSS-SECTIONS INDICATE RATHER LARGE AREA OF
CONDITIONAL SYMMETRIC INSTABILITY MATCHING UP WITH THIS BAND WHICH
WOULD EXPLAIN THE RAPID SNOW ACCUMULATIONS AT THE SFC DUE TO SOME
SLANTWISE CONVECTION. IF THE BAND STAYS TOGETHER AND CONTINUES TO
DROP SWRD...SOME QUICK ACCUMULATIONS ARE POSSIBLE OVER GRASSY
SURFACES OVER GRAND VALLEY AND AREAS SOUTH. HAVING SAID THAT...MODELS
DO KEEP THIS BAND TO OUR NORTH WITH SOME SLOW SWRD DRIFT THROUGH
THE AFTN AND EVENING. NORTH OF THIS AREA...SNOW CONTINUES TO FALL
OVER AND NEAR CRAIG...HAYDEN AND MEEKER. HILITES APPEAR TO BE ON
TRACK WITH SOME CONCERN REMAINING FOR THE UNCOMPAHGRE PLATEAU AND
NRN SAN JUANS AS RUC AND HRRR SHOW SOME DEVELOPMENT OVER THAT
AREA. OF COURSE...18Z NAM SHOWS SOME PRECIP BUT NOT ENOUGH TO
WARRANT ANY ADVISORIES. WILL NOT PULL THE TRIGGER YET BUT WILL
KEEP AN EYE ON WEBCAMS...RADAR...SATELLITE AND LOCAL SNOW REPORTS.
SFC COLD FRONT MOVED THROUGH AREA QUICKER THAN EXPECTED AND IS
CLEARLY SEEN ON WATER VAPOR AND IR IMAGERY MOVING OVR SERN CO AND
NRN NM. THE UPPER LEVEL TROF AND UPPER LOW REMAIN OVER NERN UT
ATTM AND ARE STILL EXPECTED TO MOVE OVER THE REGION THIS AFTN INTO
TONIGHT CAUSING MORE SNOWFALL. THUS...MADE LITTLE TO NO CHANGE FOR
OVERNIGHT FORECAST. SINCE SPEED OF SYSTEM HAS INCREASED
SOMEWHAT...AGREE WITH PREVIOUS THINKING THAT HILITES MAY HAVE TO
BE TAKEN DOWN EARLY PROBABLY NEARER TO EARLY SUNDAY MORNING. WILL
LEAVE AS IS FOR NOW.
BY SUNDAY...MOSTLY SUNNY SKIES FOR AREAS N AND CLEARING SKIES FOR
THE SOUTH. TEMPS WILL RUN NEAR NORMAL FOR THIS TIME OF YEAR...OR
ABOUT 10 DEGREES COOLER THAN SEEN THIS PREVIOUS WEEK. HIGH
PRESSURE WILL BUILD IN AND PERSIST THROUGH MID-WEEK.
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/
EASTERN UTAH AND WESTERN COLORADO WILL BE UNDER THE INFLUENCE OF AN
UPPER RIDGE MONDAY NIGHT AND TUESDAY...SQUEEZED BETWEEN A WRAPPED UP
SOUTHERN PLAINS LOW AND THE NEXT TROF ARRIVING OUT OF THE NORTHEAST
PACIFIC. AS SUCH THE DRY WEATHER WILL CONTINUE OVER THIS PERIOD WITH
THE WARMING ALOFT HELPING TO ENFORCE THE LOW LEVEL
INVERSIONS...ESPECIALLY IN AREAS WITH THE NEWER SNOW COVER AND DID
DIRECT TEMPERATURES TOWARD THE LOWER END OF GUIDANCE. BEYOND THIS
PERIOD CONFIDENCE CONTINUES TO WANE WITH DIFFERING MED RANGE MODEL
SOLUTIONS RELATED TO PROGRESSION OF THE WESTERN TROF. THE
DIFFERENCES ARE MOSTLY CENTERED AROUND THE EVOLUTION OF AN UPPER LOW
OVER THE SOUTHWEST CORNER OF THE CONUS AS ENERGY IN THE TROF SPLITS.
THE OPERATIONAL GFS SOLUTION IS SLOWER TO ACHIEVE THIS SPLIT WHICH
CONFLICTS WITH SOME OF IT/S MEMBERS AND WITH A REFLECTION OF A LOW
OFF THE SOCAL COAST IN THE H5 MEAN SOLUTION. THIS SLOWER SOLUTION
WOULD BE A WETTER SOLUTION AND IMPACT MORE OF THE CWA. FOR NOW
FORECAST CONTINUES TO LEAN AWAY FROM THIS TOWARD THE EURO WITH A
MORE NORTHERLY FLOW DOMINATING TUESDAY NIGHT INTO WEDNESDAY AS A
CLIPPER TYPE SYSTEM DROPS THROUGH THE NORTHERN PLAINS. THIS WOULD
BRING SOME OROGRAPHICS AND WEAK DYNAMICS TO THE CENTRAL AND NORTHERN
MOUNTAINS FOR A SLIGHT CHANCE OF SNOW. BEHIND THIS REX BLOCK SETS UP
IN THE WEST WITH DRY AND ABOVE NORMAL TEMPERATURES RETURNING TO THE
CWA FOR THE LAST HALF OF THE WEEK.
&&
.AVIATION /FOR 00Z TAF ISSUANCE/...
CONVECTIVELY DRIVEN SNOW CONTINUES ACROSS THE CENTRAL CWA...AND WILL
BE DROPPING SLOWLY SOUTH THROUGH THE EVENING AS THE MAIN SYSTEM
DROPS SOUTH OF THE GREAT BASIN. MVFR TO IFR FLIGHT CATEGORIES
CONTINUE ACROSS MUCH OF THE UPPER COLORADO RIVER BASIN INCLUDING THE
EGE AND RIL TERMINALS WHERE MODERATE SNOW BANDING PERSISTS. SLIGHT
IMPROVEMENT TO MORE WIDESPREAD MVFR AND POCKETS OF VFR IS EXPECTED
THROUGH THE EVENING HOURS AS THE MAIN DYNAMICS OF THE STORM SHIFT
SOUTH. KASE WILL EXPERIENCE LIFR/IFR CONDITIONS IN A FAVORABLE
NORTHWEST FLOW THIS EVENING WITH IMPROVEMENT EXPECTED AFTER
MIDNIGHT. MOUNTAIN OBSCURATION CAN BE EXPECTED TO PERSIST AS WELL
THROUGH THE EARLY MORNING HOURS. THE LOWER VALLEY TERMINALS OF MTJ
AND GJT LOOK TO PREVAIL AT VFR CONDITIONS THROUGH MUCH OF THIS STORM
PASSAGE...BUT TEMPORARY MVFR CONDITIONS COULD BE REALIZED AROUND THE
07/22Z-08/02Z TIME FRAME WHEN LIFT LOOKS TO BE ENHANCED OVER THIS
AREA.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL NOON MST SUNDAY FOR COZ002>005-
007>010-012-013.
UT...NONE.
&&
$$
UPDATE.......JDC
SHORT TERM...TGR
LONG TERM....15
AVIATION...15
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1108 AM MST FRI JAN 6 2012
.AVIATION...
COLD FRONT DROPPING SOUTH THROUGH THE EASTERN PLAINS...WITH BRIEF
PERIOD OF GUSTY NORTH WINDS IMMEDIATELY FOLLOWING THE FROPA. FRONT
WILL CONTINUE TO PUSH SOUTH THIS AFTERNOON...WITH WINDS GRADUALLY
SHIFTING TO THE SOUTHEAST AS HIGH PRESSURE BUILDS SOUTH THROUGH
THE PLAINS. VFR CONDITIONS WILL CONTINUE TODAY AND TONIGHT...WITH
ONLY SOME OCCASIONAL CIGS AROUND BKN120 THROUGH EARLY EVENING.
&&
.PREV DISCUSSION... /ISSUED 427 AM MST FRI JAN 6 2012/
SHORT TERM...
(TODAY AND TONIGHT)
UPPER TROF CURRENTLY MOVING ACROSS NRN U.S. ROCKIES WHICH WILL BE
SENDING A DRY COLD FRONT SOUTHWARD INTO EASTERN SECTIONS OF THE
FORECAST AREA THIS MORNING. MSAS CURRENTLY SHOWING 2-3MB 3 HR
PRESSURE RISES WORKING SOUTHWARD INTO FAR NE CO AS OF 09Z. HRRR AND
NAM12 DROP FRONT SOUTH OF THE PALMER DIVIDE SHORTLY AFTER 12Z...THEN
THROUGH MOST OF THE SE PLAINS BY 16Z. INITIALLY MIXING BEHIND THE
FRONT SHOULD HELP BOOST MAX TEMPS EARLY THIS MORNING...WITH TEMPS
THEN HOLDING STEADY OR FALLING SLIGHTLY THROUGH THE AFTERNOON.
WINDS BEHIND THE FRONT COULD BRIEFLY BECOME GUSTY AROUND 15 TO 25
MPH THROUGH THE MORNING...THOUGH SHOULD START TO DIMINISH IN THE
AFTERNOON AS SFC HIGH SETTLES IN AND LOW LEVEL FLOW SHIFTS OUT OF
THE NORTHEAST TO EAST BY EARLY EVENING. WILL ALSO SEE SOME WAVE
CLOUDINESS ACROSS NRN/EASTERN SECTIONS OF THE FCST AREA THOUGH THE
EARLY TO MID PORTION OF THE DAY. HAVE INCREASED SKY COVER GRIDS
ACCORDINGLY. AS FOR HIGHS...COOLING TODAY SHOULD DROP MAXES AROUND
10-20 DEGREES OUT EAST...AND AROUND 10 DEGREES OUT WEST. EXCEPTION
TO THIS WILL BE OVER THE SNOW PACK ACROSS THE SOUTHEAST PLAINS WHERE
MAX TEMPS WILL BE SIMILAR TO A COUPLE DEGREES COOLER THAN YESTERDAY.
TONIGHT...ATTENTION TURNS TOWARDS THE NEXT PACIFIC TROF WHICH WILL
BE ENTERING THE PACIFIC NORTHWEST AFTER 00Z AND INTO THE NRN GREAT
BASIN BY 12Z SAT. GFS AND ECMWF START TO SPREAD SNOW INTO THE
CENTRAL MTS AFTER 06-09Z. HOWEVER NAM KEEPS FCST DRY. WILL START TO
SEE MORE HIGH CLOUDINESS SPREAD IN OVERNIGHT...AND SOUNDINGS MOISTEN
DOWN TO H6 ACROSS THE CENTRAL MTS TOWARDS 12Z. THINK THE GFS AND
ECMWF MAY BE STARTING UP PCPN A LITTLE TOO QUICKLY SO WILL KEEP ANY
POPS AT OR BELOW 5 PERCENT. THIS MAY NEED TO BE RE-EVALUATED BASED
ON ANY FURTHER CHANGES IN THE MODEL TRENDS. -KT
LONG TERM...
(SATURDAY THROUGH FRIDAY)
CONTINUED TO FOLLOW THE GFS AND ECMWF FOR THE EXTENDED WITH THE
NAM BEING THE OUTLIER. AN UPPER LEVEL STORM SYSTEM IS FORECAST TO
DROP SOUTH OUT OF THE NORTHERN ROCKIES AND INTO THE INTERMOUNTAIN
WEST BEFORE TRACKING SOUTHEAST INTO THE DESERT SOUTHWEST. THIS
WILL BRING A ROUND OF SNOW TO MOST OF THE REGION BEGINNING
SATURDAY AND CLEARING THE REGION ON SUNDAY AFTERNOON. EXPECT SNOW
TO DEVELOP BY LATE MORNING ACROSS THE CENTRAL MOUNTAINS ON
SATURDAY AND SPREAD EAST INTO THE EASTERN MOUNTAINS AND PALMER
DIVIDE SATURDAY NIGHT. MODELS LESS CERTAIN ON THE PLAINS WITH
LIGHT SNOW EXPECTED THROUGH THE DAY ON SUNDAY WITH HIGHER AMOUNTS
POSSIBLE ACROSS THE NORTHEAST HALF OF THE PLAINS BEHIND A COLD
FRONT. THE AMOUNT OF SNOW OVER THE PLAINS WILL BE DEPENDENT ON THE
DEGREE OF UPSLOPE FLOW WHICH AT THIS POINT DOES NOT LOOK OVERLY
FANTASTIC. AS FAR AS SNOWFALL TOTALS...EXPECT TO SEE THE HIGHEST
AMOUNTS OVER THE CENTRAL MOUNTAINS AND PIKES PEAK WHERE GENERALLY
4 TO 8 INCHES IS POSSIBLE. OVER THE SANGRE DE CRISTO
RANGE...AMOUNTS WILL VARY WITH THE HIGHEST TOTALS...3 TO 5 INCHES
OVER NORTHERN PORTIONS OF THE RANGE. EXPECT AMOUNTS OF ONLY AN
INCH OR TWO FOR MOST OF THE PLAINS. OF NOTE...THE NAM HAS A MORE
NORTHERLY TRACK TO THE STORM SYSTEM WITH A HEAVY BAND OF SNOW
DEVELOPING ACROSS SOUTHERN HALF OF THE PLAINS AND HEAVY SNOW FOR
THE PALMER DIVIDE. THESE AREAS ACCORDING TO THE NAM WOULD HAVE
MUCH HIGHER SNOWFALL AMOUNTS...BUT GIVEN THE NAM BEING AN OUTLIER
WILL THROW OUT THE SOLUTION FOR NOW.
BEYOND SUNDAY...HIGH PRESSURE WILL SHIFT ACROSS THE ROCKIES MONDAY
AND TUESDAY BEFORE ANOTHER STORM SYSTEM MOVES INTO THE NORTHERN
CONUS. EXPECT A WARMING TREND MONDAY AND TUESDAY WITH HIGHS IN THE
MID TO UPPER 40S...EXCEPT FOR THE EASTERN PORTION OF THE ARKANSAS
RIVER VALLEY WHERE HIGHS WILL ONLY REACH THE UPPER 30S.
THE NEXT STORM SYSTEM IS FORECAST TO DROP SOUTH OUT OF CENTRAL
CANADA AND INTO THE NORTHERN PLAINS. MODELS DIFFER ON HOW FAR
SOUTH THE TROUGH DIGS WITH THE ECMWF BEING THE FURTHEST SOUTH. ONE
THING IS CERTAIN...A COLD FRONT WILL MOVE SOUTH TUESDAY NIGHT INTO
WEDNESDAY MORNING. STRONG GUSTY WINDS WILL BE POSSIBLE BEHIND THE
FRONT OVER THE PLAINS...WITH THE GFS HINTING AT VERY STRONG WINDS
NEAR THE KANSAS BORDER. TEMPERATURES WILL ALSO BE MUCH COOLER WITH
HIGHS WEDNESDAY AND THURSDAY IN THE 30S. THE MAIN QUESTION WILL BE
THE CHANCE FOR PRECIPITATION. THE GFS WITH ITS FURTHER NORTH
SOLUTION BRINGS THE FRONT THROUGH DRY...WHILE THE ECMWF HAS MORE
UPSLOPE AND DYNAMICS WITH WIDESPREAD LIGHT SNOWFALL FOR LATE
TUESDAY NIGHT INTO WEDNESDAY. FOR NOW INTRODUCED LOW POPS FOR MUCH
OF THE REGION BUT CONFIDENCE IS LOW AT THIS POINT FOR ANY TO OCCUR.
EXPECT DRY AND COOL CONDITIONS THURSDAY AND FRIDAY WITH THE REGION
UNDER NORTHWESTERLY FLOW. 88
AVIATION...
VFR CONDITIONS EXPECTED AT TAF SITES...WITH NORTH WINDS 10-15KTS
AFFECTING KCOS AND KPUB TAF SITES STARTING AROUND 12-13Z AT KCOS AND
14-15Z AT KPUB. KCOS COULD SEE SOME BRIEF GUSTS TO 25 KTS DURING
THE MORNING. OTHERWISE...SOME HIGH CIRRUS/AC EXPECTED AT KCOS AND
KPUB THROUGH THE FIRST HALF OF THE DAY. KALS WILL SEE LIGHT WINDS
THROUGH THE DAY. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 8 AM SATURDAY TO 11 AM MST SUNDAY
FOR COZ058-060.
WINTER WEATHER ADVISORY FROM 5 PM SATURDAY TO 11 AM MST SUNDAY
FOR COZ082.
&&
$$
10/28
AREA FORECAST DISCUSSION
NWS PUEBLO CO
427 AM MST FRI JAN 6 2012
.SHORT TERM...
(TODAY AND TONIGHT)
UPPER TROF CURRENTLY MOVING ACROSS NRN U.S. ROCKIES WHICH WILL BE
SENDING A DRY COLD FRONT SOUTHWARD INTO EASTERN SECTIONS OF THE
FORECAST AREA THIS MORNING. MSAS CURRENTLY SHOWING 2-3MB 3 HR
PRESSURE RISES WORKING SOUTHWARD INTO FAR NE CO AS OF 09Z. HRRR AND
NAM12 DROP FRONT SOUTH OF THE PALMER DIVIDE SHORTLY AFTER 12Z...THEN
THROUGH MOST OF THE SE PLAINS BY 16Z. INITIALLY MIXING BEHIND THE
FRONT SHOULD HELP BOOST MAX TEMPS EARLY THIS MORNING...WITH TEMPS
THEN HOLDING STEADY OR FALLING SLIGHTLY THROUGH THE AFTERNOON.
WINDS BEHIND THE FRONT COULD BRIEFLY BECOME GUSTY AROUND 15 TO 25
MPH THROUGH THE MORNING...THOUGH SHOULD START TO DIMINISH IN THE
AFTERNOON AS SFC HIGH SETTLES IN AND LOW LEVEL FLOW SHIFTS OUT OF
THE NORTHEAST TO EAST BY EARLY EVENING. WILL ALSO SEE SOME WAVE
CLOUDINESS ACROSS NRN/EASTERN SECTIONS OF THE FCST AREA THOUGH THE
EARLY TO MID PORTION OF THE DAY. HAVE INCREASED SKY COVER GRIDS
ACCORDINGLY. AS FOR HIGHS...COOLING TODAY SHOULD DROP MAXES AROUND
10-20 DEGREES OUT EAST...AND AROUND 10 DEGREES OUT WEST. EXCEPTION
TO THIS WILL BE OVER THE SNOW PACK ACROSS THE SOUTHEAST PLAINS WHERE
MAX TEMPS WILL BE SIMILAR TO A COUPLE DEGREES COOLER THAN YESTERDAY.
TONIGHT...ATTENTION TURNS TOWARDS THE NEXT PACIFIC TROF WHICH WILL
BE ENTERING THE PACIFIC NORTHWEST AFTER 00Z AND INTO THE NRN GREAT
BASIN BY 12Z SAT. GFS AND ECMWF START TO SPREAD SNOW INTO THE
CENTRAL MTS AFTER 06-09Z. HOWEVER NAM KEEPS FCST DRY. WILL START TO
SEE MORE HIGH CLOUDINESS SPREAD IN OVERNIGHT...AND SOUNDINGS MOISTEN
DOWN TO H6 ACROSS THE CENTRAL MTS TOWARDS 12Z. THINK THE GFS AND
ECMWF MAY BE STARTING UP PCPN A LITTLE TOO QUICKLY SO WILL KEEP ANY
POPS AT OR BELOW 5 PERCENT. THIS MAY NEED TO BE RE-EVALUATED BASED
ON ANY FURTHER CHANGES IN THE MODEL TRENDS. -KT
.LONG TERM...
(SATURDAY THROUGH FRIDAY)
CONTINUED TO FOLLOW THE GFS AND ECMWF FOR THE EXTENDED WITH THE
NAM BEING THE OUTLIER. AN UPPER LEVEL STORM SYSTEM IS FORECAST TO
DROP SOUTH OUT OF THE NORTHERN ROCKIES AND INTO THE INTERMOUNTAIN
WEST BEFORE TRACKING SOUTHEAST INTO THE DESERT SOUTHWEST. THIS
WILL BRING A ROUND OF SNOW TO MOST OF THE REGION BEGINNING
SATURDAY AND CLEARING THE REGION ON SUNDAY AFTERNOON. EXPECT SNOW
TO DEVELOP BY LATE MORNING ACROSS THE CENTRAL MOUNTAINS ON
SATURDAY AND SPREAD EAST INTO THE EASTERN MOUNTAINS AND PALMER
DIVIDE SATURDAY NIGHT. MODELS LESS CERTAIN ON THE PLAINS WITH
LIGHT SNOW EXPECTED THROUGH THE DAY ON SUNDAY WITH HIGHER AMOUNTS
POSSIBLE ACROSS THE NORTHEAST HALF OF THE PLAINS BEHIND A COLD
FRONT. THE AMOUNT OF SNOW OVER THE PLAINS WILL BE DEPENDENT ON THE
DEGREE OF UPSLOPE FLOW WHICH AT THIS POINT DOES NOT LOOK OVERLY
FANTASTIC. AS FAR AS SNOWFALL TOTALS...EXPECT TO SEE THE HIGHEST
AMOUNTS OVER THE CENTRAL MOUNTAINS AND PIKES PEAK WHERE GENERALLY
4 TO 8 INCHES IS POSSIBLE. OVER THE SANGRE DE CRISTO
RANGE...AMOUNTS WILL VARY WITH THE HIGHEST TOTALS...3 TO 5 INCHES
OVER NORTHERN PORTIONS OF THE RANGE. EXPECT AMOUNTS OF ONLY AN
INCH OR TWO FOR MOST OF THE PLAINS. OF NOTE...THE NAM HAS A MORE
NORTHERLY TRACK TO THE STORM SYSTEM WITH A HEAVY BAND OF SNOW
DEVELOPING ACROSS SOUTHERN HALF OF THE PLAINS AND HEAVY SNOW FOR
THE PALMER DIVIDE. THESE AREAS ACCORDING TO THE NAM WOULD HAVE
MUCH HIGHER SNOWFALL AMOUNTS...BUT GIVEN THE NAM BEING AN OUTLIER
WILL THROW OUT THE SOLUTION FOR NOW.
BEYOND SUNDAY...HIGH PRESSURE WILL SHIFT ACROSS THE ROCKIES MONDAY
AND TUESDAY BEFORE ANOTHER STORM SYSTEM MOVES INTO THE NORTHERN
CONUS. EXPECT A WARMING TREND MONDAY AND TUESDAY WITH HIGHS IN THE
MID TO UPPER 40S...EXCEPT FOR THE EASTERN PORTION OF THE ARKANSAS
RIVER VALLEY WHERE HIGHS WILL ONLY REACH THE UPPER 30S.
THE NEXT STORM SYSTEM IS FORECAST TO DROP SOUTH OUT OF CENTRAL
CANADA AND INTO THE NORTHERN PLAINS. MODELS DIFFER ON HOW FAR
SOUTH THE TROUGH DIGS WITH THE ECMWF BEING THE FURTHEST SOUTH. ONE
THING IS CERTAIN...A COLD FRONT WILL MOVE SOUTH TUESDAY NIGHT INTO
WEDNESDAY MORNING. STRONG GUSTY WINDS WILL BE POSSIBLE BEHIND THE
FRONT OVER THE PLAINS...WITH THE GFS HINTING AT VERY STRONG WINDS
NEAR THE KANSAS BORDER. TEMPERATURES WILL ALSO BE MUCH COOLER WITH
HIGHS WEDNESDAY AND THURSDAY IN THE 30S. THE MAIN QUESTION WILL BE
THE CHANCE FOR PRECIPITATION. THE GFS WITH ITS FURTHER NORTH
SOLUTION BRINGS THE FRONT THROUGH DRY...WHILE THE ECMWF HAS MORE
UPSLOPE AND DYNAMICS WITH WIDESPREAD LIGHT SNOWFALL FOR LATE
TUESDAY NIGHT INTO WEDNESDAY. FOR NOW INTRODUCED LOW POPS FOR MUCH
OF THE REGION BUT CONFIDENCE IS LOW AT THIS POINT FOR ANY TO OCCUR.
EXPECT DRY AND COOL CONDITIONS THURSDAY AND FRIDAY WITH THE REGION
UNDER NORTHWESTERLY FLOW. MOZLEY
&&
.AVIATION...
VFR CONDITIONS EXPECTED AT TAF SITES...WITH NORTH WINDS 10-15KTS
AFFECTING KCOS AND KPUB TAF SITES STARTING AROUND 12-13Z AT KCOS AND
14-15Z AT KPUB. KCOS COULD SEE SOME BRIEF GUSTS TO 25 KTS DURING
THE MORNING. OTHERWISE...SOME HIGH CIRRUS/AC EXPECTED AT KCOS AND
KPUB THROUGH THE FIRST HALF OF THE DAY. KALS WILL SEE LIGHT WINDS
THROUGH THE DAY. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 8 AM SATURDAY TO 11 AM MST SUNDAY
FOR COZ058-060.
WINTER WEATHER ADVISORY FROM 5 PM SATURDAY TO 11 AM MST SUNDAY
FOR COZ082.
&&
$$
31/88
AREA FORECAST DISCUSSION
NWS TAUNTON MA
725 AM EST FRI JAN 6 2012
.SYNOPSIS...
OTHER THAN A FEW BRIEF SNOW SHOWERS EARLY THIS MORNING...DRY WEATHER
WITH MODERATING TEMPERATURES ARE EXPECTED TODAY AND SATURDAY. A COLD
FRONT WILL BRING A RETURN TO MORE SEASONABLE TEMPERATURES BY SUNDAY
AND MONDAY. MILDER WEATHER WILL RETURN TUESDAY AND WEDNESDAY WITH A
STORM LIKELY AFFECTING THE REGION WEDNESDAY NIGHT INTO THURSDAY.
&&
.NEAR TERM /UNTIL 9 AM THIS MORNING/...
7AM UPDATE...
WARM FRONT CURRENTLY MOVING THROUGH CENTRAL PORTIONS OF THE FA
THIS MORNING BASED ON CURRENT DWPT OBS AND SATELLITE. OVERRUNNING
-SHSN HAS ALSO MOSTLY MOVED N AND E OF THE REGION. GIVEN THIS
EXPECTING SKIES TO GRADUALLY CLEAR THIS MORNING AND INTO THE
AFTERNOON. TEMPS GRADUALLY INCREASE AS WELL BEHIND THE
FRONT...EXPECTING MID 40S S OF THE MASS PIKE. UPDATES MADE TO
POPS/SKY AND TEMPS/DWPTS. HRRR HANDLED TIMING OF PRECIP WELL THE
LAST FEW HOURS...AND 06/06Z MAV WAS USED AS BASIS FOR TEMPS/DWPTS.
PREVIOUS DISCUSSION...
DOPPLER RADAR AND SURFACE OBSERVATIONS WERE SHOWING THAT SCATTERED
LIGHT SNOW SHOWERS/FLURRIES WERE OVER SPREADING OUR REGION IN
ADVANCE OF A WARM FRONT. THIS ACTIVITY WILL BE SHORT LIVED AND ANY
SNOW ACCUMULATIONS WILL BE VERY LIGHT AND SPOTTY. HOWEVER...A
COATING OF SNOW IS CERTAINLY POSSIBLE IN SOME LOCATIONS. THIS
COULD RESULT IN SOME SLIPPERY SPOTS FOR THE EARLY MORNING RUSH
HOUR.
ANY SCATTERED LIGHT SNOW SHOWERS SHOULD BE VERY SHORT LIVED AND EXPECT
MOST OF THE PRECIPITATION TO MOVE TO THE NORTH OF OUR COUNTY WARNING
AREA BY MID MORNING AT THE LATEST.
&&
.SHORT TERM /9 AM THIS MORNING THROUGH 6 PM SATURDAY/...
MID MORNING AND INTO THE AFTERNOON...
THE MID LEVELS OF THE ATMOSPHERE WILL RAPIDLY WARM FROM SOUTHWEST TO
NORTHEAST ONCE THE WARM FRONT MOVES THROUGH THE REGION. WHILE THE
WARM ADVECTION PATTERN WILL LIKELY RESULT IN CONSIDERABLE CLOUDINESS
INTO MUCH OF THE AFTERNOON...A FEW BREAKS WILL LIKELY DEVELOP AT
TIMES SOUTH OF THE MA TURNPIKE. DEPENDING ON HOW MANY BREAKS
DEVELOP IN THE CLOUDS...HIGH TEMPERATURES SHOULD RECOVER WELL UP
INTO THE 40S TO NEAR 50 SOUTH OF THE MA TURNPIKE.
MEANWHILE...ACROSS SOUTHERN NH/NORTHERN MA THE WARM FRONT WILL BE
SLOW TO MOVE INTO THAT REGION AND THERE AND CLOUDS WILL LIKELY HANG
TOUGH. THIS SHOULD HOLD HIGH TEMPERATURES IN THE UPPER 30S AND
LOWER 40S.
TONIGHT...
A DRY AND PLEASANT NIGHT FOR EARLY JANUARY STANDARDS IS ON TAP FOR
THE REGION. LOW TEMPERATURES SHOULD ONLY FALL INTO THE MIDDLE TO
UPPER 20S ACROSS THE INTERIOR...WITH READINGS LIKELY STAYING ABOVE
FREEZING FOR MOST OF THE COASTAL PLAIN AS SOUTHWEST WINDS WILL NOT
COMPLETELY DECOUPLE IN THIS REGION. IN FACT...WEST TO SOUTHWEST
FLOW OVER THE OCEAN SHOULD KEEP NANTUCKET FROM DROPPING BELOW 40!
SATURDAY...
WEAK LOW PRESSURE MOVING ACROSS SOUTHERN CANADA AND NORTHERN NEW
ENGLAND WILL RESULT IN AN UNSEASONABLY MILD DAY ACROSS OUR REGION.
WITH DECENT MIXING ON WESTERLY FLOW AND PARTLY TO MOSTLY SUNNY SKIES
HIGH TEMPERATURES SHOULD CLIMB WELL INTO THE 40S TO POSSIBLY EVEN
SOME LOWER 50S ACROSS PORTIONS OF THE COASTAL PLAIN.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGHLIGHTS...
* MORE SEASONABLE SUN AND MON
* MILDER TEMPERATURES RETURN TUE AND WED WITH DRY WX CONTINUING
* MAINLY RAIN EVENT WED NIGHT INTO THURSDAY...BUT LOW PROB FOR
A PERIOD OF ICE OR SNOW IN THE DISTANT INTERIOR
OVERVIEW AND MODEL PREFERENCES...
06/00Z GUIDANCE SUITE IS IN GENERALLY GOOD AGREEMENT ON THE BROAD
SCALE PATTERN THROUGH MID NEXT WEEK...WITH MOSTLY SUBTLE
DIFFERENCES IN SFC FEATURES. BASE OF BROAD ERN CANADIAN TROF RESTS
GENERALLY JUST W OF NEW ENGLAND...WHILE WRN EXTENT OF ATLANTIC
RIDGING KEEPS DRY AIRMASS IN PLACE OVER THE REGION.
THEREFORE...EVEN AS SHORTWAVES PUSH THROUGH THE FAST FLOW AT THE
BASE OF THE TROF...THERE IS LITTLE CHANGE IN THE SENSIBLE WX SAVE
FOR TEMPS DIFFERENCES AS WEAK COLD FRONTS CROSS THE AREA THROUGH
TUE. THEREFORE...WILL REMAIN CONSISTENT WITH FCST SUGGESTING
MOSTLY DRY CONDITIONS BUT SOME SLIGHT COOLING AS THE TROF DIGS
INTO THE COMING WORK WEEK. SENSIBLE WX MID AND LATE THIS COMING
WEEK WILL BE DEFINED BY A PROGGED PATTERN SHIFT...WHICH MODELS
CONTINUE TO STRUGGLE WITH. THE KEY IS THE GRADUAL DEVELOPMENT OF A
NEAR REX TYPE BLOCK WITH CUTOFF LOW OVER THE SW AND A BUILDING
RIDGE OVER THE CENTRAL CONUS. WHILE THE ERN CANADIAN TROF AND
CUTOFF SHOW SOME PHASING EARLY IN THE WEEK...THE NRN TROF EJECTS E
AHEAD...ALLOWING THE CUTOFF AND RIDGE TO INTERACT AND MOVE SLOWLY
E. THERE CONTINUE TO BE SPATIAL AND TEMPORAL DIFFERENCES BETWEEN
OPNL GFS/ECMWF AND SEVERAL OF THEIR ENSEMBLE MEMBERS...HOWEVER IT
APPEARS THAT THE CUTOFF WILL DRY A STRONG SFC LOW SOMEWHERE OVER
NEW ENGLAND MID TO LATE NEXT WEEK WITH STRONG WARM RIDGING
BUILDING IN ADVANCE. THERE ARE STILL MANY DETAILS TO NAIL DOWN
WITH THIS POTENTIALLY HIGH IMPACT FEATURE...BUT THE WAVE THAT
FORMS THE CUTOFF WILL ONLY BEGIN TO BE SAMPLED BY LAND BASED
OBSERVATIONS IN THE NEXT 24 HOURS...SO THERE MAY BE BETTER SOLN
CONVERGENCE OVER THE WEEKEND. GIVEN THE AGREEMENT EARLY IN THE
LONG TERM...AND THE DISAGREEMENT LATE...WILL STICK TO THE OPNL GFS
AND ECMWF BLEND AS A BASIS FOR THE LONG TERM.
DETAILS...
SAT NIGHT INTO SUN...
CLIPPER SYSTEM OVER NRN NEW ENGLAND CONTINUES TO MOVE E INTO THE
MARITIMES...DRAGGING A COLD FRONT OVER SNE DURING THE DAY SUN. THE
COMBINATION OF AN ALREADY DRY AIRMASS BASED ON MODEL SOUNDINGS AND
SOME WEAK SUBSIDENCE IN CAA AHEAD OF THE FRONT SUGGEST THAT THE
FRONT MOVES THROUGH WITH LITTLE PRECIPITATION.
H92 TEMPS GRADUALLY DECREASE TO AROUND -4C TO -5C...DESPITE SOME
EXPECTED CLOUD COVER...MIXING WILL LIKELY BE ALLOWED TO REACH THIS
LEVEL. TEMPS LOOK TO BE SLIGHTLY ABOVE NORMAL DESPITE THE COOLER
FROPA.
MON THRU WED...
STRONG HIGH PRES BUILDS IN FROM THE W...CRESTING OVER THE REGION
LATE MON NIGHT. THE DRY AIRMASS REMAINS IN PLACE AND BEST FORCING
WITH A WEAK SHORTWAVE DURING THE DAY TUE REMAINS WELL TO THE
N...SO GENERALLY DRY WX PERSISTS. TEMPS INITIALLY DROP TO NEAR OR
JUST BELOW NORMAL INTO THE DAY MON...BEFORE RETURN FLOW /AS RIDGE
CRESTS SHIFTS E OF THE REGION/ ALLOWS SLIGHT WAA AND HEIGHT
RISES. 1000-500 THICKNESS VALUES REACH THE 540S BY WED...SO ABOVE
AVERAGE TEMPS EXPECTED BY MID WEEK.
THU AND FRI...
WARM RIDGE CONTINUES TO BUILD OVER THE ERN CONUS AS CUTOFF LOW
GRADUALLY OPENS AND EJECTS TO THE NE. THIS CUTOFF WILL ALLOW A
STRONG SFC LOW TO AFFECT SNE THU INTO FRI. GIVEN THAT THERE ARE
STILL SOME TEMPORAL DIFFERENCES BETWEEN MODELS...THERE ARE
DIFFERENCES IN THE P-TYPE IN THIS STORM. WHILE COLUMN SUGGESTS A
MOSTLY RAIN EVENT. SOME COOL LLVL AIR BOTH IN ADVANCE OF THE STORM
AND IN ITS WAKE SUGGEST A MIX OF SOME ICE...ESPECIALLY ON THE
/CURRENTLY COOLER/ GFS.
&&
.AVIATION /13Z FRIDAY THROUGH TUESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT
MODERATE...30 PERCENT TO 60 PERCENT
HIGH...GREATER THAN 60 PERCENT
TODAY...HIGH CONFIDENCE VFR AFTER SNOW SHOWERS CLEAR IN THE NEXT
COUPLE OF HOURS. REMAINING MVFR CONDITIONS OVER OUTER CAPE
TERMINALS AT THIS TIME. CIGS GRADUALLY LIFT TO A MID DECK THEN
BECOME PARTLY CLOUDY THIS AFTERNOON AND EVENING.
TONIGHT AND SATURDAY...HIGH CONFIDENCE IN VFR REMAINS DOMINANT
CATEGORY. S WINDS 5 TO 10 KT TODAY...10 TO 20 OVER ACK/HYA/FMH.
WINDS SHIFT TO SW SATURDAY.
KBOS TERMINAL...HIGH CONFIDENCE IN VFR CONDITIONS TODAY AND
TONIGHT. S WINDS 5 TO 10 KT TODAY...SHIFTING TO SW TOMORROW.
OUTLOOK...SATURDAY NIGHT THROUGH TUESDAY...
MODERATE TO HIGH CONFIDENCE VFR THROUGH THE PERIOD WITH HIGH
PRESSURE MOVING OVER THE REGION.
&&
.MARINE...
TODAY...
A WARM FRONT WILL MOVE ACROSS THE WATERS TODAY. BEHIND THE WARM
FRONT...EXPECT SOUTHWEST WIND GUSTS OF 25 TO 30 KNOTS TO DEVELOP
ACROSS THE SOUTHERN WATERS. SEAS WILL ALSO BUILD TO BETWEEN 4 AND 7
FEET ACROSS THE OPEN WATERS WITH A GOOD SOUTHWEST FETCH.
THEREFORE...SCA WILL BE IN EFFECT LATER THIS MORNING AND AFTERNOON.
TONIGHT...
WEST TO SOUTHWEST WINDS WILL CONTINUE TO GUST TO 25 KNOTS AT TIMES
ACROSS THE SOUTHERN WATERS. IN ADDITION...SEAS WILL REMAIN AT OR
ABOVE 5 FEET IN THIS REGION. THEREFORE...WILL CONTINUE SCA
HEADLINES FOR OUR SOUTHERN WATERS.
SATURDAY...
WESTERLY WINDS ARE EXPECTED AS WEAK LOW PRESSURE TRACKS ACROSS
NORTHERN NEW ENGLAND AND SOUTHERN CANADA. MARGINAL 25 KNOT GUSTS
WILL BE POSSIBLE ACROSS THE SOUTHERN WATERS. FOR NOW HAVE JUST
EXTENDED SCA FOR THE SOUTHERN OUTER-WATERS SINCE SEAS WILL BE AT OR
ABOVE 5 FEET. LATER SHIFTS MAY HAVE TO EXPAND THE SCA HEADLINES A
BIT FURTHER NORTH...BUT IT APPEARS MARGINAL AT THIS POINT.
OUTLOOK...SATURDAY NIGHT THROUGH TUESDAY...
SATURDAY NIGHT INTO SUNDAY...
WINDS GUSTING TO AROUND 25 KT ESPECIALLY SAT NIGHT AS A COLD FRONT
APPROACHES AND CROSSES THE WATERS. ELEVATED ABOVE SCA THRESHOLDS
INTO THE EARLY PART OF THE DAY SUN. CONDITIONS DIMINISH BELOW SCA
THRESHOLDS DURING THE DAY SUN.
MONDAY AND TUESDAY...
WINDS AND SEAS EXPECTED TO REMAIN BELOW SCA. W/NW WINDS MON
BECOMING SW MON NIGHT AND TUE.
&&
.EQUIPMENT...
THE KBOX 88D IS OUT OF SERVICE UNTIL JAN 15TH DUE TO A
HARDWARE UPGRADE.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST SATURDAY FOR ANZ232>235-
237.
SMALL CRAFT ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR ANZ231-
236.
SMALL CRAFT ADVISORY UNTIL 7 PM EST SATURDAY FOR ANZ254>256.
&&
$$
SYNOPSIS...FRANK/DOODY
NEAR TERM...FRANK/DOODY
SHORT TERM...FRANK
LONG TERM...DOODY
AVIATION...DOODY
MARINE...FRANK/DOODY
EQUIPMENT...STAFF
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
838 PM EST SAT JAN 7 2012
.UPDATE...
WEAK CONVECTION ALONG A SURFACE/LOW LEVEL TROUGH HAS ENDED OVER SE
GA AS THE RUC INDICATED IT WOULD. SURFACE RIDGE AXIS REMAINS SOUTH
OF THE AREA. A SHORTWAVE TROUGH PRODUCING TSTMS TO OUR NORTH WILL
REMAIN THERE AND NOT EXPECTING ANY MORE SHOWERS TONIGHT...BUT
MODELS SUGGEST A REPEAT OF SHOWERS MAINLY OVER SE GA SUNDAY AFTN.
MODELS ARE NOT HITTING FOG QUITE AS MUCH TONIGHT ALTHO ADVECTION
FOG IS STILL EXPECTED TO ADVANCE INLAND FROM THE GULF COAST AND
MARCH TO THE EAST COAST LATE TONIGHT. HAVE TWEAKED GRIDS TO SHOW
FOG BEGINNING AROUND 03Z WEST OF I-75 CORRIDOR AND STEADILY MOVING
EASTWARD. OTHERWISE ONLY MINOR TWEAKS HAS BEEN MADE TO TEMPS.
&&
.AVIATION...EXPECT LOWERING VSBYS/CIGS LATER TONIGHT ONCE LOW LEVEL
TROUGH OVER SE GA AND WEST COAST SEA BREEZE BECOME DIFFUSE. TEMPS
WERE IN THE LOWER 50S INLAND AROUND 830 EST...WITH DEW PTS NEAR 50
WITH CALM WINDS AND MOSTLY CLEAR SKIES. THUS AS DECOUPLING JUST
ABOVE THE SFC INCREASES...SUSPECT VSBYS AND LOW CIGS WILL DEVELOP.
HAVE GNV AND VQQ DROPPING TO VLIFR AROUND 06-07Z...WITH LIFR AT JAX
AND CRG. WILL NEED TO MONITOR SSI WITH ONLY MVFR FORECAST AT THIS
TIME SINCE MID CLOUDS WILL BE INCREASE FROM THE WEST.
&&
.MARINE...WSW 10 KTS AND SEAS 1-3 FT TONIGHT. NO HEADLINES...EXCEPT
IF DENSE FOG DRIFTS OFFSHORE OF THE COAST EARLY SUN MORNING AS WAS
THE CASE THIS MORNING. VSBYS COULD BE 1 NM OR LESS IF FOG BANK DOES
MATERIALIZE LATE TONIGHT.
RIP CURRENTS: MODERATE RISK LIKELY ON SUNDAY DUE TO LINGERING LONG
PERIOD EAST SWELLS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 47 73 49 74 / 10 10 10 10
SSI 51 68 53 71 / 10 10 10 10
JAX 48 73 51 75 / 10 10 10 10
SGJ 50 69 52 72 / 10 10 10 0
GNV 47 74 49 76 / 10 10 10 0
OCF 47 75 50 76 / 10 10 10 0
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
TRABERT/ENYEDI/LETRO
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1112 AM CST FRI JAN 6 2012
.DISCUSSION...
ISSUED 936 AM CST FRI JAN 6 2012
COLD FRONT CURRENTLY INDICATED ON SURFACE ANALYSIS ROUGHLY ALONG A
KANSAS CITY TO GREEN BAY LINE...WITH 12Z MODELS SHOWING AN EARLY
TO MID AFTERNOON PASSAGE ACROSS CENTRAL AND SOUTHEAST ILLINOIS.
WITH JUST SOME CIRRUS WITH IT...WILL ONCE AGAIN GET GOOD MIXING
FROM AROUND 900 MB AND TEMPERATURES PUSHING THE 60 DEGREE MARK
OVER MOST OF THE SOUTHWEST HALF OF THE CWA. HAVE SENT SOME UPDATED
GRIDS TO REFINE HOURLY TEMPERATURE AND DEWPOINT TRENDS...BUT
EARLIER FORECAST LOOKS GOOD OVERALL AND NO CHANGES NEEDED TO THE
WORDED FORECASTS.
GEELHART
&&
.AVIATION...
ISSUED 1111 AM CST FRI JAN 6 2012
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. A COLD FRONT WILL PUSH
ACROSS CENTRAL ILLINOIS GENERALLY IN THE 20Z-01Z PERIOD...TURNING
WINDS MORE TOWARD THE NORTHWEST. CLOUDINESS WITH IT WILL MAINLY
BE 10KFT OR HIGHER.
GEELHART
&&
.PREV DISCUSSION...
ISSUED 325 AM CST FRI JAN 6 2012
ANOTHER UNSEASONABLY MILD DAY EXPECTED TODAY ACROSS CENTRAL AND SE
IL WITH TEMPERATURES MORE LIKE LATE MARCH INSTEAD OF EARLY
JANUARY. WILL CONTINUE TO SIDE WARMER THAN GUIDANCE TEMPS ESPECIALLY
CENTRAL AND SOUTHERN AREAS AS GUIDANCE AS BEEN MUCH TOO COOL FOR
HIGHS DURING THE PAST FEW DAYS. QUIET WEATHER STILL EXPECTED
THROUGH TUE ALONG WITH ABOVE NORMAL TEMPERATURES. 00Z MODELS STILL
DIFFER WITH HANDLING OF CUTOFF LOW MOVING EAST ACROSS THE SOUTHERN
STATES DURING THE MIDDLE PART OF NEXT WEEK. GFS AND GEM MODELS
STILL APPEAR TO FAST AND WILL LEAN TOWARD THE SLOWER ECMWF MODEL.
FORECAST CONCERN IS PRECIPITATION CHANCES AND TYPE WED AND WED
NIGHT.
SHORT TERM...TODAY THROUGH TUESDAY
PREDAWN SURFACE MAP SHOWS ELONGATED 994 MB LOW PRESSURE OVER SW
ONTARIO NORTH OF MN WITH A COLD FRONT OVER NW PARTS OF WI AND IA.
1024 MB HIGH PRESSURE WAS OVER THE GULF OF MEXICO KEEPING MOISTURE
LOCKED NEAR THE GULF COAST. MAINLY CLEAR SKIES OVER CENTRAL AND
SOUTHERN IL EARLY THIS MORNING WITH CIRRUS CLOUDS OVER NORTHERN
IL FROM I-80 NORTH. MILD TEMPS MAINLY IN THE UPPER 30S TO MID 40S
EXCEPT COOLER 34F AT PEORIA AND 48F AT JACKSONVILLE AND 50F AT
PITTSFIELD. DEWPOINTS WERE IN THE LOWER 30S WITH SSW WINDS 5 TO 15
MPH. NEARLY ZONAL UPPER LEVEL FLOW PREVAILS ACROSS THE NORTHERN
HALF OF THE COUNTRY.
MODELS BRING THE WEAK COLD FRONT SE THROUGH THE IL RIVER VALLEY
THIS AFTERNOON THROUGH SUNSET AND THROUGH SE IL THIS EVENING.
MOSTLY SUNNY SKIES EXPECTED TODAY WITH JUST INCREASING HIGH CLOUDS
WHILE COLD AIR ADVECTION LAGS BEHIND THE COLD FRONT. WILL LEAN
TOWARD THE WARMER HRRR MODEL FOR HIGHS IN THE MID 50S FROM THE IL
RIVER NW AND LOWER 60S FROM SPRINGFIELD TO ROBINSON SOUTH. THIS IS
STILL SHY OF RECORD HIGHS IN THE MID 60S TO AROUND 70F. COOLER
LOWS TONIGHT IN THE LOW TO MID 30S WHICH IS ACTUALLY CLOSE TO
NORMAL HIGHS FOR EARLY JANUARY OVER CENTRAL IL.
MODELS HAVE TRENDED WEAKER WITH UPPER LEVEL TROF OVER THE UPPER
MIDWEST THIS WEEKEND WITH NEARLY ZONAL FLOW STILL OVER CENTRAL IL.
THIS COMBINED WITH A FAIR AMOUNT OF SUNSHINE SAT WILL NUDGE HIGHS
UP INTO THE MID TO UPPER 40S WITH 50F AT LAWRENCEVILLE. MID AND
HIGH CLOUDS INCREASE SUNDAY AHEAD OF AN UPPER LEVEL TROF MOVING
INTO THE UPPER MS VALLEY AND CENTRAL PLAINS. A BIT COOLER HIGHS IN
THE MID 40S SUNDAY DUE TO MORE CLOUDS. THESE CLOUDS TO DECREASE
FROM NW TO SE OVERNIGHT SUNDAY NIGHT INTO MON MORNING AS SURFACE
HIGH PRESSURE RIDGE SETTLES INTO CENTRAL IL WHILE UPPER LEVEL TROF
BEGINS TO PULL AWAY FROM IL AS UPPER LEVEL HEIGHTS RISE AGAIN.
HIGHS IN THE MID TO UPPER 40S MON AND UPPER 40S AND LOWER 50S TUE
WITH MOSTLY SUNNY SKIES.
LONG TERM...TUESDAY NIGHT THROUGH FRIDAY
CONTINUED TO LEAN ON THE SLOWER ECMWF MODEL WITH HANDLING OF
CUTOFF LOW EJECTING FROM THE SW STATES DURING MIDDLE OF NEXT WEEK
REACHING THE LOWER MS VALLEY TUE NIGHT AND OVER THE TN VALLEY WED.
THIS MODEL HAS TRENDED FURTHER SE WITH QPF OVER SE IL WED WHILE
GEM IS DRY OVER IL. MEANWHILE GFS MODEL WHICH WAS DRY YESTERDAY
NOW IS THE WETTER MODEL WITH SPREADING QPF ACROSS CENTRAL IL
DURING WED. WITH ALL THESE DIFFERENCES WILL LEAVE THE ALLBLEND
POPS INTACT WITH SMALL CHANCES OF LIGHT RAIN OVERNIGHT TUE NIGHT
OVER SE IL AND 20-40% CHANCE OF LIGHT RAIN WED WITH SLIGHT CHANCES
NW OVER THE IL RIVER VALLEY WHILE 40% IN SE IL. MEANWHILE A STRONG
NORTHERN STREAM UPPER LEVEL TROF/LOW TO DIG SOUTH INTO THE MIDWEST
WED AND WED NIGHT PUSHING THE SOUTHERN STREAM SYSTEM INTO THE MID
ATLANTIC STATES WED NIGHT. BRUNT OF PRECIPITATION TO SHIFT EAST OF
IL WED NIGHT AND THU AS COLDER AIR USHERS INTO IL. THIS TO CHANGE
LIGHT RAIN SHOWERS TO LIGHT SNOW SHOWERS DURING WED NIGHT AND A
FEW LIGHT SNOW SHOWERS POSSIBLY LINGERING THU ESPECIALLY IN
EASTERN IL. TEMPS FINALLY COOL BACK TO NORMAL THU AND THEN DRY AND
SEASONABLY COLD NEXT FRI.
HUETTL
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
937 AM CST FRI JAN 6 2012
.DISCUSSION...
ISSUED 936 AM CST FRI JAN 6 2012
COLD FRONT CURRENTLY INDICATED ON SURFACE ANALYSIS ROUGHLY ALONG A
KANSAS CITY TO GREEN BAY LINE...WITH 12Z MODELS SHOWING AN EARLY
TO MID AFTERNOON PASSAGE ACROSS CENTRAL AND SOUTHEAST ILLINOIS.
WITH JUST SOME CIRRUS WITH IT...WILL ONCE AGAIN GET GOOD MIXING
FROM AROUND 900 MB AND TEMPERATURES PUSHING THE 60 DEGREE MARK
OVER MOST OF THE SOUTHWEST HALF OF THE CWA. HAVE SENT SOME UPDATED
GRIDS TO REFINE HOURLY TEMPERATURE AND DEWPOINT TRENDS...BUT
EARLIER FORECAST LOOKS GOOD OVERALL AND NO CHANGES NEEDED TO THE
WORDED FORECASTS.
GEELHART
&&
.AVIATION...
ISSUED 539 AM CST FRI JAN 6 2012
QUIET/VFR AVIATION WEATHER CONDITIONS EXPECTED THROUGH THE 12Z TAF
VALID TIME. A COLD FRONT WILL PASS THROUGH THE CENTRAL ILLINOIS
TERMINALS LATER TODAY...PROVIDING LITTLE MORE THAN A WIND SHIFT.
SOME MID/HIGH LEVEL VFR CIGS ARE LIKELY FOR A FEW HOURS AFTER
FROPA.
BAK
&&
.PREV DISCUSSION...
ISSUED 325 AM CST FRI JAN 6 2012
ANOTHER UNSEASONABLY MILD DAY EXPECTED TODAY ACROSS CENTRAL AND SE
IL WITH TEMPERATURES MORE LIKE LATE MARCH INSTEAD OF EARLY
JANUARY. WILL CONTINUE TO SIDE WARMER THAN GUIDANCE TEMPS ESPECIALLY
CENTRAL AND SOUTHERN AREAS AS GUIDANCE AS BEEN MUCH TOO COOL FOR
HIGHS DURING THE PAST FEW DAYS. QUIET WEATHER STILL EXPECTED
THROUGH TUE ALONG WITH ABOVE NORMAL TEMPERATURES. 00Z MODELS STILL
DIFFER WITH HANDLING OF CUTOFF LOW MOVING EAST ACROSS THE SOUTHERN
STATES DURING THE MIDDLE PART OF NEXT WEEK. GFS AND GEM MODELS
STILL APPEAR TO FAST AND WILL LEAN TOWARD THE SLOWER ECMWF MODEL.
FORECAST CONCERN IS PRECIPITATION CHANCES AND TYPE WED AND WED
NIGHT.
SHORT TERM...TODAY THROUGH TUESDAY
PREDAWN SURFACE MAP SHOWS ELONGATED 994 MB LOW PRESSURE OVER SW
ONTARIO NORTH OF MN WITH A COLD FRONT OVER NW PARTS OF WI AND IA.
1024 MB HIGH PRESSURE WAS OVER THE GULF OF MEXICO KEEPING MOISTURE
LOCKED NEAR THE GULF COAST. MAINLY CLEAR SKIES OVER CENTRAL AND
SOUTHERN IL EARLY THIS MORNING WITH CIRRUS CLOUDS OVER NORTHERN
IL FROM I-80 NORTH. MILD TEMPS MAINLY IN THE UPPER 30S TO MID 40S
EXCEPT COOLER 34F AT PEORIA AND 48F AT JACKSONVILLE AND 50F AT
PITTSFIELD. DEWPOINTS WERE IN THE LOWER 30S WITH SSW WINDS 5 TO 15
MPH. NEARLY ZONAL UPPER LEVEL FLOW PREVAILS ACROSS THE NORTHERN
HALF OF THE COUNTRY.
MODELS BRING THE WEAK COLD FRONT SE THROUGH THE IL RIVER VALLEY
THIS AFTERNOON THROUGH SUNSET AND THROUGH SE IL THIS EVENING.
MOSTLY SUNNY SKIES EXPECTED TODAY WITH JUST INCREASING HIGH CLOUDS
WHILE COLD AIR ADVECTION LAGS BEHIND THE COLD FRONT. WILL LEAN
TOWARD THE WARMER HRRR MODEL FOR HIGHS IN THE MID 50S FROM THE IL
RIVER NW AND LOWER 60S FROM SPRINGFIELD TO ROBINSON SOUTH. THIS IS
STILL SHY OF RECORD HIGHS IN THE MID 60S TO AROUND 70F. COOLER
LOWS TONIGHT IN THE LOW TO MID 30S WHICH IS ACTUALLY CLOSE TO
NORMAL HIGHS FOR EARLY JANUARY OVER CENTRAL IL.
MODELS HAVE TRENDED WEAKER WITH UPPER LEVEL TROF OVER THE UPPER
MIDWEST THIS WEEKEND WITH NEARLY ZONAL FLOW STILL OVER CENTRAL IL.
THIS COMBINED WITH A FAIR AMOUNT OF SUNSHINE SAT WILL NUDGE HIGHS
UP INTO THE MID TO UPPER 40S WITH 50F AT LAWRENCEVILLE. MID AND
HIGH CLOUDS INCREASE SUNDAY AHEAD OF AN UPPER LEVEL TROF MOVING
INTO THE UPPER MS VALLEY AND CENTRAL PLAINS. A BIT COOLER HIGHS IN
THE MID 40S SUNDAY DUE TO MORE CLOUDS. THESE CLOUDS TO DECREASE
FROM NW TO SE OVERNIGHT SUNDAY NIGHT INTO MON MORNING AS SURFACE
HIGH PRESSURE RIDGE SETTLES INTO CENTRAL IL WHILE UPPER LEVEL TROF
BEGINS TO PULL AWAY FROM IL AS UPPER LEVEL HEIGHTS RISE AGAIN.
HIGHS IN THE MID TO UPPER 40S MON AND UPPER 40S AND LOWER 50S TUE
WITH MOSTLY SUNNY SKIES.
LONG TERM...TUESDAY NIGHT THROUGH FRIDAY
CONTINUED TO LEAN ON THE SLOWER ECMWF MODEL WITH HANDLING OF
CUTOFF LOW EJECTING FROM THE SW STATES DURING MIDDLE OF NEXT WEEK
REACHING THE LOWER MS VALLEY TUE NIGHT AND OVER THE TN VALLEY WED.
THIS MODEL HAS TRENDED FURTHER SE WITH QPF OVER SE IL WED WHILE
GEM IS DRY OVER IL. MEANWHILE GFS MODEL WHICH WAS DRY YESTERDAY
NOW IS THE WETTER MODEL WITH SPREADING QPF ACROSS CENTRAL IL
DURING WED. WITH ALL THESE DIFFERENCES WILL LEAVE THE ALLBLEND
POPS INTACT WITH SMALL CHANCES OF LIGHT RAIN OVERNIGHT TUE NIGHT
OVER SE IL AND 20-40% CHANCE OF LIGHT RAIN WED WITH SLIGHT CHANCES
NW OVER THE IL RIVER VALLEY WHILE 40% IN SE IL. MEANWHILE A STRONG
NORTHERN STREAM UPPER LEVEL TROF/LOW TO DIG SOUTH INTO THE MIDWEST
WED AND WED NIGHT PUSHING THE SOUTHERN STREAM SYSTEM INTO THE MID
ATLANTIC STATES WED NIGHT. BRUNT OF PRECIPITATION TO SHIFT EAST OF
IL WED NIGHT AND THU AS COLDER AIR USHERS INTO IL. THIS TO CHANGE
LIGHT RAIN SHOWERS TO LIGHT SNOW SHOWERS DURING WED NIGHT AND A
FEW LIGHT SNOW SHOWERS POSSIBLY LINGERING THU ESPECIALLY IN
EASTERN IL. TEMPS FINALLY COOL BACK TO NORMAL THU AND THEN DRY AND
SEASONABLY COLD NEXT FRI.
HUETTL
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
539 AM CST FRI JAN 6 2012
.DISCUSSION...
ISSUED 325 AM CST FRI JAN 6 2012
ANOTHER UNSEASONABLY MILD DAY EXPECTED TODAY ACROSS CENTRAL AND SE
IL WITH TEMPERATURES MORE LIKE LATE MARCH INSTEAD OF EARLY
JANUARY. WILL CONTINUE TO SIDE WARMER THAN GUIDANCE TEMPS ESPECIALLY
CENTRAL AND SOUTHERN AREAS AS GUIDANCE AS BEEN MUCH TOO COOL FOR
HIGHS DURING THE PAST FEW DAYS. QUIET WEATHER STILL EXPECTED
THROUGH TUE ALONG WITH ABOVE NORMAL TEMPERATURES. 00Z MODELS STILL
DIFFER WITH HANDLING OF CUTOFF LOW MOVING EAST ACROSS THE SOUTHERN
STATES DURING THE MIDDLE PART OF NEXT WEEK. GFS AND GEM MODELS
STILL APPEAR TO FAST AND WILL LEAN TOWARD THE SLOWER ECMWF MODEL.
FORECAST CONCERN IS PRECIPITATION CHANCES AND TYPE WED AND WED
NIGHT.
SHORT TERM...TODAY THROUGH TUESDAY
PREDAWN SURFACE MAP SHOWS ELONGATED 994 MB LOW PRESSURE OVER SW
ONTARIO NORTH OF MN WITH A COLD FRONT OVER NW PARTS OF WI AND IA.
1024 MB HIGH PRESSURE WAS OVER THE GULF OF MEXICO KEEPING MOISTURE
LOCKED NEAR THE GULF COAST. MAINLY CLEAR SKIES OVER CENTRAL AND
SOUTHERN IL EARLY THIS MORNING WITH CIRRUS CLOUDS OVER NORTHERN
IL FROM I-80 NORTH. MILD TEMPS MAINLY IN THE UPPER 30S TO MID 40S
EXCEPT COOLER 34F AT PEORIA AND 48F AT JACKSONVILLE AND 50F AT
PITTSFIELD. DEWPOINTS WERE IN THE LOWER 30S WITH SSW WINDS 5 TO 15
MPH. NEARLY ZONAL UPPER LEVEL FLOW PREVAILS ACROSS THE NORTHERN
HALF OF THE COUNTRY.
MODELS BRING THE WEAK COLD FRONT SE THROUGH THE IL RIVER VALLEY
THIS AFTERNOON THROUGH SUNSET AND THROUGH SE IL THIS EVENING.
MOSTLY SUNNY SKIES EXPECTED TODAY WITH JUST INCREASING HIGH CLOUDS
WHILE COLD AIR ADVECTION LAGS BEHIND THE COLD FRONT. WILL LEAN
TOWARD THE WARMER HRRR MODEL FOR HIGHS IN THE MID 50S FROM THE IL
RIVER NW AND LOWER 60S FROM SPRINGFIELD TO ROBINSON SOUTH. THIS IS
STILL SHY OF RECORD HIGHS IN THE MID 60S TO AROUND 70F. COOLER
LOWS TONIGHT IN THE LOW TO MID 30S WHICH IS ACTUALLY CLOSE TO
NORMAL HIGHS FOR EARLY JANUARY OVER CENTRAL IL.
MODELS HAVE TRENDED WEAKER WITH UPPER LEVEL TROF OVER THE UPPER
MIDWEST THIS WEEKEND WITH NEARLY ZONAL FLOW STILL OVER CENTRAL IL.
THIS COMBINED WITH A FAIR AMOUNT OF SUNSHINE SAT WILL NUDGE HIGHS
UP INTO THE MID TO UPPER 40S WITH 50F AT LAWRENCEVILLE. MID AND
HIGH CLOUDS INCREASE SUNDAY AHEAD OF AN UPPER LEVEL TROF MOVING
INTO THE UPPER MS VALLEY AND CENTRAL PLAINS. A BIT COOLER HIGHS IN
THE MID 40S SUNDAY DUE TO MORE CLOUDS. THESE CLOUDS TO DECREASE
FROM NW TO SE OVERNIGHT SUNDAY NIGHT INTO MON MORNING AS SURFACE
HIGH PRESSURE RIDGE SETTLES INTO CENTRAL IL WHILE UPPER LEVEL TROF
BEGINS TO PULL AWAY FROM IL AS UPPER LEVEL HEIGHTS RISE AGAIN.
HIGHS IN THE MID TO UPPER 40S MON AND UPPER 40S AND LOWER 50S TUE
WITH MOSTLY SUNNY SKIES.
LONG TERM...TUESDAY NIGHT THROUGH FRIDAY
CONTINUED TO LEAN ON THE SLOWER ECMWF MODEL WITH HANDLING OF
CUTOFF LOW EJECTING FROM THE SW STATES DURING MIDDLE OF NEXT WEEK
REACHING THE LOWER MS VALLEY TUE NIGHT AND OVER THE TN VALLEY WED.
THIS MODEL HAS TRENDED FURTHER SE WITH QPF OVER SE IL WED WHILE
GEM IS DRY OVER IL. MEANWHILE GFS MODEL WHICH WAS DRY YESTERDAY
NOW IS THE WETTER MODEL WITH SPREADING QPF ACROSS CENTRAL IL
DURING WED. WITH ALL THESE DIFFERENCES WILL LEAVE THE ALLBLEND
POPS INTACT WITH SMALL CHANCES OF LIGHT RAIN OVERNIGHT TUE NIGHT
OVER SE IL AND 20-40% CHANCE OF LIGHT RAIN WED WITH SLIGHT CHANCES
NW OVER THE IL RIVER VALLEY WHILE 40% IN SE IL. MEANWHILE A STRONG
NORTHERN STREAM UPPER LEVEL TROF/LOW TO DIG SOUTH INTO THE MIDWEST
WED AND WED NIGHT PUSHING THE SOUTHERN STREAM SYSTEM INTO THE MID
ATLANTIC STATES WED NIGHT. BRUNT OF PRECIPITATION TO SHIFT EAST OF
IL WED NIGHT AND THU AS COLDER AIR USHERS INTO IL. THIS TO CHANGE
LIGHT RAIN SHOWERS TO LIGHT SNOW SHOWERS DURING WED NIGHT AND A
FEW LIGHT SNOW SHOWERS POSSIBLY LINGERING THU ESPECIALLY IN
EASTERN IL. TEMPS FINALLY COOL BACK TO NORMAL THU AND THEN DRY AND
SEASONABLY COLD NEXT FRI.
HUETTL
&&
.AVIATION...
ISSUED 539 AM CST FRI JAN 6 2012
QUIET/VFR AVIATION WEATHER CONDITIONS EXPECTED THROUGH THE 12Z TAF
VALID TIME. A COLD FRONT WILL PASS THROUGH THE CENTRAL ILLINOIS
TERMINALS LATER TODAY...PROVIDING LITTLE MORE THAN A WIND SHIFT.
SOME MID/HIGH LEVEL VFR CIGS ARE LIKELY FOR A FEW HOURS AFTER
FROPA.
BAK
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
327 AM CST FRI JAN 6 2012
.DISCUSSION...
ISSUED 325 AM CST FRI JAN 6 2012
ANOTHER UNSEASONABLY MILD DAY EXPECTED TODAY ACROSS CENTRAL AND SE
IL WITH TEMPERATURES MORE LIKE LATE MARCH INSTEAD OF EARLY
JANUARY. WILL CONTINUE TO SIDE WARMER THAN GUIDANCE TEMPS ESPECIALLY
CENTRAL AND SOUTHERN AREAS AS GUIDANCE AS BEEN MUCH TOO COOL FOR
HIGHS DURING THE PAST FEW DAYS. QUIET WEATHER STILL EXPECTED
THROUGH TUE ALONG WITH ABOVE NORMAL TEMPERATURES. 00Z MODELS STILL
DIFFER WITH HANDLING OF CUTOFF LOW MOVING EAST ACROSS THE SOUTHERN
STATES DURING THE MIDDLE PART OF NEXT WEEK. GFS AND GEM MODELS
STILL APPEAR TO FAST AND WILL LEAN TOWARD THE SLOWER ECMWF MODEL.
FORECAST CONCERN IS PRECIPITATION CHANCES AND TYPE WED AND WED
NIGHT.
SHORT TERM...TODAY THROUGH TUESDAY
PREDAWN SURFACE MAP SHOWS ELONGATED 994 MB LOW PRESSURE OVER SW
ONTARIO NORTH OF MN WITH A COLD FRONT OVER NW PARTS OF WI AND IA.
1024 MB HIGH PRESSURE WAS OVER THE GULF OF MEXICO KEEPING MOISTURE
LOCKED NEAR THE GULF COAST. MAINLY CLEAR SKIES OVER CENTRAL AND
SOUTHERN IL EARLY THIS MORNING WITH CIRRUS CLOUDS OVER NORTHERN
IL FROM I-80 NORTH. MILD TEMPS MAINLY IN THE UPPER 30S TO MID 40S
EXCEPT COOLER 34F AT PEORIA AND 48F AT JACKSONVILLE AND 50F AT
PITTSFIELD. DEWPOINTS WERE IN THE LOWER 30S WITH SSW WINDS 5 TO 15
MPH. NEARLY ZONAL UPPER LEVEL FLOW PREVAILS ACROSS THE NORTHERN
HALF OF THE COUNTRY.
MODELS BRING THE WEAK COLD FRONT SE THROUGH THE IL RIVER VALLEY
THIS AFTERNOON THROUGH SUNSET AND THROUGH SE IL THIS EVENING.
MOSTLY SUNNY SKIES EXPECTED TODAY WITH JUST INCREASING HIGH CLOUDS
WHILE COLD AIR ADVECTION LAGS BEHIND THE COLD FRONT. WILL LEAN
TOWARD THE WARMER HRRR MODEL FOR HIGHS IN THE MID 50S FROM THE IL
RIVER NW AND LOWER 60S FROM SPRINGFIELD TO ROBINSON SOUTH. THIS IS
STILL SHY OF RECORD HIGHS IN THE MID 60S TO AROUND 70F. COOLER
LOWS TONIGHT IN THE LOW TO MID 30S WHICH IS ACTUALLY CLOSE TO
NORMAL HIGHS FOR EARLY JANUARY OVER CENTRAL IL.
MODELS HAVE TRENDED WEAKER WITH UPPER LEVEL TROF OVER THE UPPER
MIDWEST THIS WEEKEND WITH NEARLY ZONAL FLOW STILL OVER CENTRAL IL.
THIS COMBINED WITH A FAIR AMOUNT OF SUNSHINE SAT WILL NUDGE HIGHS
UP INTO THE MID TO UPPER 40S WITH 50F AT LAWRENCEVILLE. MID AND
HIGH CLOUDS INCREASE SUNDAY AHEAD OF AN UPPER LEVEL TROF MOVING
INTO THE UPPER MS VALLEY AND CENTRAL PLAINS. A BIT COOLER HIGHS IN
THE MID 40S SUNDAY DUE TO MORE CLOUDS. THESE CLOUDS TO DECREASE
FROM NW TO SE OVERNIGHT SUNDAY NIGHT INTO MON MORNING AS SURFACE
HIGH PRESSURE RIDGE SETTLES INTO CENTRAL IL WHILE UPPER LEVEL TROF
BEGINS TO PULL AWAY FROM IL AS UPPER LEVEL HEIGHTS RISE AGAIN.
HIGHS IN THE MID TO UPPER 40S MON AND UPPER 40S AND LOWER 50S TUE
WITH MOSTLY SUNNY SKIES.
LONG TERM...TUESDAY NIGHT THROUGH FRIDAY
CONTINUED TO LEAN ON THE SLOWER ECMWF MODEL WITH HANDLING OF
CUTOFF LOW EJECTING FROM THE SW STATES DURING MIDDLE OF NEXT WEEK
REACHING THE LOWER MS VALLEY TUE NIGHT AND OVER THE TN VALLEY WED.
THIS MODEL HAS TRENDED FURTHER SE WITH QPF OVER SE IL WED WHILE
GEM IS DRY OVER IL. MEANWHILE GFS MODEL WHICH WAS DRY YESTERDAY
NOW IS THE WETTER MODEL WITH SPREADING QPF ACROSS CENTRAL IL
DURING WED. WITH ALL THESE DIFFERENCES WILL LEAVE THE ALLBLEND
POPS INTACT WITH SMALL CHANCES OF LIGHT RAIN OVERNIGHT TUE NIGHT
OVER SE IL AND 20-40% CHANCE OF LIGHT RAIN WED WITH SLIGHT CHANCES
NW OVER THE IL RIVER VALLEY WHILE 40% IN SE IL. MEANWHILE A STRONG
NORTHERN STREAM UPPER LEVEL TROF/LOW TO DIG SOUTH INTO THE MIDWEST
WED AND WED NIGHT PUSHING THE SOUTHERN STREAM SYSTEM INTO THE MID
ATLANTIC STATES WED NIGHT. BRUNT OF PRECIPITATION TO SHIFT EAST OF
IL WED NIGHT AND THU AS COLDER AIR USHERS INTO IL. THIS TO CHANGE
LIGHT RAIN SHOWERS TO LIGHT SNOW SHOWERS DURING WED NIGHT AND A
FEW LIGHT SNOW SHOWERS POSSIBLY LINGERING THU ESPECIALLY IN
EASTERN IL. TEMPS FINALLY COOL BACK TO NORMAL THU AND THEN DRY AND
SEASONABLY COLD NEXT FRI.
HUETTL
&&
.AVIATION...
ISSUED 1132 PM CST THU JAN 5 2012...FOR THE 06Z TAFS
VFR CONDITIONS WILL CONTINUE OVER THE NEXT 24 HOURS. THE QUIET
WEATHER CAN BE ATTRIBUTED TO HIGH PRESSURE AHEAD OF THE NEXT COLD
FRONT/TROUGH. STEADY SW WINDS AT 8-12KT WILL CONTINUE THROUGH
FRIDAY AFTERNOON...WHEN THE COLD FRONT MAKES PROGRESS ACROSS C IL
FROM WEST TO EAST. THE FRONT SHOULD REACH PIA BY 18Z AND CMI BY
22Z. WINDS WILL BECOME WEST BY EVENING AND EVENTUALLY NW BY MIDNIGHT.
THE FRONT WILL BE MOISTURE STARVED...SO ONLY SOME MID AND HIGH
CLOUDS ARE EXPECTED WITH THE FRONT. NO REDUCTIONS TO VISIBILITY
ARE EXPECTED.
SHIMON
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1007 PM EST SAT JAN 7 2012
.SYNOPSIS...
CHILLY NORTHWEST WINDS IN THE WAKE OF A COLD FRONT WILL PROVIDE
CLOUDS OVERNIGHT WITH ISOLATED LIGHT FLURRIES ACROSS THE I-80
CORRIDOR. MIDWEST HIGH PRESSURE WILL PROVIDE SOME SUN AND MILD
TEMPERATURES SUNDAY INTO TUESDAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
PER RECENT SATELLITE DATA, HAVE ADJUSTED FORECAST OF POST FRONTAL
CLOUD INCREASE OVERNIGHT. PER RECENT HRRR AND NAM MODEL OUTPUT, CONTINUE
TO EXPECT MOSTLY CLOUDY SKIES NORTH OF THE I-70 CORRIDOR WITH
ISOLATED ISOLATED SNOW FLURRIES WITHIN THE I-80 CORRIDOR.
EASTBOUND HIGH PRESSURE SHOULD PROVIDE ENOUGH OF A CLOUD DECREASE
SUNDAY FOR SOME SUN EVERYWHERE BY AFTERNOON.
FORECASTED TEMPERATURES TO CONTINUE WARMER THAN NORMAL PER BLEND
OF RECENT GFS AND NAM MOS.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
BLEND OF NAM/GFS/ECMWF MODEL OUTPUT SHOW MIDWEST HIGH PRESSURE
COMING EASTBOUND TO PROVIDE DRY, MILD CONDITIONS THIS PERIOD.
FORECASTED TEMPERATURE DETAILS, USING BLEND OF GFS AND NAM MOS.
DUE TO INCREASED RADIATIONAL EFFECTS PER REDUCED CLOUD COVER,
EXPECT LOWS ABOUT 5 DEGREES WARMER THAN NORMAL AND HIGHS CLOSER TO
10 DEGREES WARMER THAN NORMAL.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
A CLOSED MID-LEVEL LOW WILL MOVE FROM THE WESTERN GULF STATES ACROSS
THE TENNESSEE VALLEY TUESDAY NIGHT INTO WEDNESDAY. THE CHANCE OF
RAIN WILL ARRIVE LATE TUESDAY NIGHT AS A WARM FRONT AHEAD OF THE LOW
PUSHES NORTHWARD INTO THE AREA. MODEL THICKNESSES WILL WARM ABOVE
CRITICAL THRESHOLDS THAT WOULD BE NEEDED FOR A WINTRY MIX, SO
FORECAST IS FOR ALL RAIN TO BEGIN THE EVENT. TEMPERATURES WILL BE
AROUND 10 DEGREES ABOVE NORMAL THROUGH THE MID-WEEK.
RAIN WILL BE LIKELY ACROSS THE REGION WEDNESDAY INTO WEDNESDAY NIGHT
AS THE LOW MOVES ACROSS WEST VIRGINIA AND INTO THE NORTHEAST. BY
THURSDAY MORNING LOW WILL BE EXITING EAST AS QUITE STRONG NORTHERN
BRANCH CLOSED UPPER LOW DIGS ACROSS THE GREAT LAKES. THIS NORTHERN
BRANCH LOW WILL BRING MUCH COLDER AIR INTO REGION STARTING THURSDAY
AND CONTINUING INTO THE START OF THE WEEKEND. RAIN SHOWERS WILL MIX
WITH AND CHANGE TO SNOW THURSDAY FOLLOWED BY NORTHWEST FLOW SNOW
SHOWERS INTO FRIDAY. BY SATURDAY A RIDGE OF HIGH PRESSURE WILL BRING
DRY AND COLD CONDITIONS. AS ALSO SUPPORTED BY NAEFS MEDIAN VALUES, TEMPERATURES
WILL FALL TO 5 TO 10 DEGREES BELOW NORMAL LATE WEEK.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
PER RECENT SURFACE AND SATELLITE DATA, EXPECT VFR STRATOCUMULUS
TO SPREAD EAST SOUTHEASTWARD ACROSS THE UPPER OHIO VALLEY
OVERNIGHT. ITS POSSIBLE CEILINGS CAN LOWER TO MVFR LEVELS ACROSS
THE I-80 CORRIDOR WHERE ISOLATED MVFR FLURRIES MAY ALSO OCCUR.
PER NAM MODEL OUTPUT, EXPECT THESE COLD POOL CLOUDS TO RECEDE
NORTH DAYTIME SUNDAY. HENCE VFR WILL CONTINUE TO BE PREVALENT.
OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...
VFR INTO TUESDAY NIGHT. NORTHEASTBOUND LOW PRESSURE FROM LOUISIANA
WILL PROVIDE MIXED PRECIPITATION AND RESTRICTIONS WEDNESDAY AND
THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
708 PM EST SAT JAN 7 2012
.SYNOPSIS...
CHILLY NORTHWEST WINDS IN THE WAKE OF A COLD FRONT WILL PROVIDE
INCREASING CLOUDS OVERNIGHT AND ISOLATED LIGHT SNOW SHOWERS
ACROSS THE I-80 CORRIDOR. MIDWEST HIGH PRESSURE WILL PROVIDE SOME
SUN AND MILD TEMPERATURES SUNDAY AND MONDAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
PER RECENT SATELLITE DATA, HAVE SLOWED FORECAST OF POST FRONTAL
CLOUD INCREASE THIS EVENING. PER RECENT HRRR AND NAM MODEL OUTPUT,
CONTINUE TO EXPECT PARTLY TO MOSTLY CLOUDY SKIES NORTH OF THE I-70
CORRIDOR LATE TONIGHT. ISOLATED LIGHT SNOW SHOWERS OR FLURRIES CAN
OCCUR WITHIN THE I-80 CORRIDOR.
EASTBOUND HIGH PRESSURE SHOULD PROVIDE ENOUGH OF A CLOUD DECREASE
SUNDAY FOR SOME SUN.
FORECASTED TEMPERATURES TO CONTINUE WARMER THAN NORMAL PER BLEND
OF RECENT GFS AND NAM MOS.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
BLEND OF NAM/GFS/ECMWF MODEL OUTPUT SHOW MIDWEST HIGH PRESSURE
COMING EASTBOUND TO PROVIDE DRY, MILD CONDITIONS THIS PERIOD.
FORECASTED TEMPERATURE DETAILS, USING BLEND OF GFS AND NAM MOS, SHOWED
INCREASED RADIATIONAL EFFECTS PER REDUCED CLOUD COVERS PROVIDING LOWS
ABOUT 5 DEGREES WARMER THAN NORMAL WITH HIGHS CLOSER TO 10 DEGREES
WARMER THAN NORMAL.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
A CLOSED MID-LEVEL LOW WILL MOVE FROM THE WESTERN GULF STATES ACROSS
THE TENNESSEE VALLEY TUESDAY NIGHT INTO WEDNESDAY. THE CHANCE OF
RAIN WILL ARRIVE LATE TUESDAY NIGHT AS A WARM FRONT AHEAD OF THE LOW
PUSHES NORTHWARD INTO THE AREA. MODEL THICKNESSES WILL WARM ABOVE
CRITICAL THRESHOLDS THAT WOULD BE NEEDED FOR A WINTRY MIX, SO
FORECAST IS FOR ALL RAIN TO BEGIN THE EVENT. TEMPERATURES WILL BE
AROUND 10 DEGREES ABOVE NORMAL THROUGH THE MID-WEEK.
RAIN WILL BE LIKELY ACROSS THE REGION WEDNESDAY INTO WEDNESDAY NIGHT
AS THE LOW MOVES ACROSS WEST VIRGINIA AND INTO THE NORTHEAST. BY
THURSDAY MORNING LOW WILL BE EXITING EAST AS QUITE STRONG NORTHERN
BRANCH CLOSED UPPER LOW DIGS ACROSS THE GREAT LAKES. THIS NORTHERN
BRANCH LOW WILL BRING MUCH COLDER AIR INTO REGION STARTING THURSDAY
AND CONTINUING INTO THE START OF THE WEEKEND. RAIN SHOWERS WILL MIX
WITH AND CHANGE TO SNOW THURSDAY FOLLOWED BY NORTHWEST FLOW SNOW
SHOWERS INTO FRIDAY. BY SATURDAY A RIDGE OF HIGH PRESSURE WILL BRING
DRY AND COLD CONDITIONS. TEMPERATURES WILL FALL TO 5 TO 10
DEGREES BELOW NORMAL LATE WEEK.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AS OF EARLY EVENING...EXTENSIVE LOW VFR CEILING EXTENDS FROM
NORTHERN OHIO NORTHWEST INTO MICHIGAN. THESE CLOUDS ARE EXPECTED TO
MOVE SOUTHEAST...ENTERING PENNSYLVANIA BY MIDNIGHT. THINK THAT
NORTHERN SITES (FKL...DUJ...BVI) WILL SEE CIGS DROP TO MVFR...BUT
HAVE KEPT VFR CIGS ELSEWHERE. HOWEVER...MODEL SOUNDINGS INDICATE
THAT THERE IS THE POTENTIAL FOR LOW LEVELS TO SATURATE ELSEWHERE AND
ALLOW FOR CIGS TO LOWER TO MVFR. CEILINGS SHOULD SCATTER SOMEWHAT
SUNDAY AFTERNOON...BECOMING MORE OF A CUMULUS DECK. WINDS WILL
REMAIN BELOW 10 KT THROUGHOUT THE PERIOD.
OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...
HIGH PRESSURE WILL GIVE GENERAL VFR CONDITIONS INTO TUESDAY NIGHT.
LOW PRESSURE WILL APPROACH LATER TUESDAY NIGHT WITH RESTRICTIONS
WEDNESDAY AND THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
642 PM EST SAT JAN 7 2012
UPDATED AVIATION DISCUSSION FOR 00Z TAFS
.SYNOPSIS...
WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL NRN STREAM
FLOW THROUGH THE UPPER GREAT LAKES. A WEAK SHORTWAVE THAT HAS HELPED
BOOST LES INTENSITY TODAY WAS EXITING TO THE EAST OF LAKE SUPERIOR.
OTHERWISE...NO SIGNIFICANT SHRTWVS WERE NOTED UPSTREAM THAT WOULD
IMPACT WEATHER THROUGH SUN. AT THE SFC...A TROUGH FRONT WAS NEARLY
STATIONARY ACROSS NRN UPPER MI. 850 MB TEMPS NEAR -14C PROVIDED JUST
ENOUGH INSTABILITY FOR LIGHT LES WITH LOW LEVEL NW FLOW.
&&
.SHORT TERM...TONIGHT AND SUNDAY
WEAKER AND INCREASINGLY ANTICYCLONIC FLOW WITH SFC RDG MOVING IN
FROM THE WEST WILL TEND TO BACK WINDS MORE WRLY LATE TONIGHT INTO
SUNDAY. THE MOST FAVORABLE LOW LEVEL CONV WOULD FOCUS LES OVER THE
KEWEENAW PENINSULA AND FROM MUNISING EASTWARD ALONG THE ERN
SHORELINE. MAINTAINED HIGH CHC TO LIKELY POPS FOR ADDITIONAL LES
ACCUMS OF AN INCH OR LESS OVER THE KEWEENAW PENINSULA AND ERN
ALGER...LUCE AND NRN SCHOOLCRAFT COUNTIES. EXPECT DRY CONDITIONS TO
THE SOUTH.
A BAND OF 275K-280K ISENTROPIC ASCENT AND 900-800 MB FGEN MOVING
INTO THE WEST LATE AND ACROSS THE CWA LATE TONIGHT AND SUN MORNING
COULD PRODUCE SOME LIGHT SNOW WITH MINIMAL ACCUMULATIONS OF A FEW
TENTHS. SO...ONLY SLIGHT CHANCE POPS WERE INCLUDED AWAY FROM LAKE
SUPERIOR. LOW LEVEL BACKING MORE WRLY BY SUNDAY ALONG WITH MARGINAL
LAKE INSTABILITY (850 MB TEMPS CLIMBING TO AROUND -12C) SUPPORT ONLY
LOW CHC POPS FOR LES OVER MAINLY THE KEWEENAW PENINSULA AND
SHORELINE AREAS EAST OF MUNISING. WITH THE LIGHT WIND FIELD
UNCERTAINTY REMAINS WHETHER ANY MESO LOW OR SHORELINE PARALLEL BAND
WILL DEVELOP...PER HIGH RES WRF/ARW.
.LONG TERM /00Z MON THROUGH NEXT SAT/...
STARTING MONDAY AT 00Z THERE WILL BE A BROAD 500MB TROUGH OVER ERN
CANADA/NERN CONUS...WITH A SHARP TROUGH BRANCHING OFF OF THAT FROM
OVER OUR CWA TO THE AZ/NM BORDER...AND A 500MB RIDGE W OF THAT
TROUGH. BY TUESDAY...THE AZ/NM TROUGH WILL CLOSE OFF AND MOVE TO
TX...BREAKING FREE OF THE ERN CANADA TROUGH AS IT MOVES E. ANOTHER
SYSTEM WILL PUSH INTO THE PACIFIC NW...WHICH WILL PUSH THE W COAST
RIDGE OVER THE CWA DURING THE DAY TUESDAY. MODELS HAVE HAD POOR RUN
TO RUN CONTINUITY WITH THE NEXT SYSTEM MOVING IN FOR THE MIDDLE OF
THE WEEK. MODELS BRING AN UPPER TROUGH OFF A CLOSED LOW OVER AK INTO
THE REGION...DEEPENING IT INTO A CLOSED LOW NEAR OR OVER THE CWA
WED. THE CLOSED LOW MOVES OFF TO THE NE THU NIGHT OR FRIDAY...WITH
AN UPPER TROUGH HANGING AROUND E OF THE CWA THROUGH SATURDAY.
FOR MON...A SHORTWAVE WILL MOVE THROUGH THE REGION...BUT THE BEST
DYNAMICS WILL BE FARTHER NE...SO ANY POPS WERE LIMITED TO LAKE
SUPERIO OR ERN UPPER MI. EVEN WITH CLOUD COVER FROM THIS
SYSTEM...HIGH WILL BE IN THE MID TO UPPER 30S WITH WAA FROM THE W
THROUGH THE DAY. 850MB TEMPS AT 00Z MON WILL BE AROUND
-9C...INCREASING TO AROUND 0C BY 00Z TUE.
MON NIGHT AND TUE...AS THE UPPER RIDGE MOVES OVERHEAD TUE...EXPECT
DRY CONDITIONS WITH FEWER CLOUDS...ESPECIALLY BEFORE EVENING.
THICKNESSES WILL BE SLIGHTLY INCREASED TUE...SO HIGHS WILL BE A
COUPLE DEGREES WARMER AROUND 40.
WED THROUGH FRI...AS NOTED PREVIOUSLY...MODELS SHOW INCREASED
DISAGREEMENT AND DECREASED RUN TO RUN CONTINUITY WITH A SYSTEM
EJECTING OUT OF AK. COMPARING THE 12Z/07 GFS...00Z/07 ECMWF...AND
12Z/07 GEM SOLUTIONS...THE GEM WAS RULED OUT SINCE IT SHOWS A FAR
DIFFERENT SCENARIO THAN THE OTHER TWO MODELS. BOTH THE GFS AND ECMWF
BRING A 500MB TROUGH FROM A CLOSED LOW OVER AK...SHOWING A LOW
CLOSING OFF FROM THE TIP OF THE TROUGH AS IT MOVES SE. MODELS THEN
DEPICT THE TROUGH MOVING TOWARD THE CWA BEFORE DEEPENING JUST
UPSTREAM OF THE CWA IN RESPONSE TO JET INTERACTION. THE GFS CLOSES
THE UPPER LOW OFF AS IT MOVES ACROSS THE CENTRAL MANITOBA/ONTARIO
BORDER AROUND 18Z WED...AND MARCHES IT JUST N OF LAKE SUPERIOR
BEFORE MOVING INTO QUEBEC AROUND 06Z FRI. THE STRONGER ECMWF CLOSES
THE LOW OFF OVER THE ND/MANITOBA BORDER AROUND 12Z WED...THEN
CONTINUES TO DEEPEN THE SYSTEM AS IT MOVES TO THE IL/WI BORDER BY
12Z THU...THEN TO THE LOWER GREAT LAKES BY 12Z FRI. SET THE CLOCK
BACK A BIT TO FIND WHERE MODELS START TO DIVERGE WITH THIS SYSTEM.
BACK WHEN THE TROUGH IS MOVING OVER WRN CANADA...THE SLIGHTLY
STRONGER ECMWF IS MUCH FASTER TO CLOSE OFF THAT LOW...WHICH THEN
MOVES S AND STAYS WELL OFF THE CA COAST THROUGH THE EVENT. THE
GFS...ON THE OTHER HAND...CLOSES THE LOW OFF OVER SRN CA...WHICH
LEADS TO THAT LOW MOVING INTO AZ AND NM THROUGH THE EVENT. HAVING
THAT LOW IN PLACE THE GFS PUTS IT CUTS OFF SOME ACCESS TO COMPONENTS
OF BOTH THE NRN AND SRN STREAM JETS...WHICH IS WHY THE SYSTEM DOES
NOT STRENGTHEN AS MUCH AND STAYS FARTHER N WITH THE GFS SOLUTION.
REGARDLESS OF SOLUTION...BOTH MODELS BRING 850MB TEMPS AS LOW AS
-20C OVER LAKE SUPERIOR WITH THE SYSTEM. THE GFS HAS NW BL
WINDS...WHILE THE ECMWF HAS MORE NORTHERLY WINDS SINCE THE SFC LOW
WILL BE MORE TO OUR E. AT THIS POINT...I FEEL COMFORTABLE WITH
LIKELY POPS SINCE CONFIDENCE THAT IT WILL SNOW IS MUCH HIGHER THAN
THE CONFIDENCE OF WHERE THE MOST SNOW WILL FALL. IF THE ECMWF IS
CORRECT...WE COULD BE LOOKING AT VERY SIGNIFICANT SNOWFALL
AMOUNTS...ESPECIALLY IN NORTH WIND SNOWBELTS. THE GFS SOLUTION WOULD
LEAD TO MUCH LOWER SNOWFALL TOTALS THAN THE ECMWF...SINCE THE ECMWF
ALSO CONTRIBUTES A SIGNIFICANT AMOUNT OF SYNOPTIC PRECIP.
&&
.AVIATION /FOR THE 00Z TAF ISSUANCE/...
LK EFFECT SNOW SHOWERS WILL CONTINUE AT KIWD AND KCMX THROUGH MOST
OF THE TAF PERIOD. AS WINDS TURN TO A MORE UNFAVORABLE W DIRECTION
AT KSAW...EXPECT SHSN TO DISSIPATE EARLY. A WEAK SURFACE WAVE TO THE
WEST WILL TRAVERSE LAKE SUPERIOR OVERNIGHT...ALLOWING LOW LEVEL
MOISTURE TO INCREASE AND CEILINGS TO DROP TO MVFR AT ALL TAF SITES.
EXPECT WEAK LOW TO MOVE OUT DURING THE DAY TOMORROW...IMPROVING
CONDITIONS AT ALL SITES BY AFTERNOON. THERE IS A SMALL RISK OF
FREEZING DRIZZLE LATE TONIGHT AS WELL...IF LOW LEVELS CONTINUE TO
WARM AND AN INVERSION FORMS...BUT CONFIDENCE AT THIS TIME IS NOT
HIGH. MODELS ALSO GAVE AN INDICATION THAT CMX WOULD SEE FOG AND LIFR
CONDITIONS AFTER 12Z...BUT WIND DIRECTION IS NOT FAVORABLE AND
CONTINUED FALLING SNOW WILL MOST LIKELY LEAVE IT AT A LOW STRATUS
DECK.
&&
.MARINE /FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE/...
LOW PRESSURE IS FORECAST TO SLIDE ACROSS ONTARIO THROUGH MONDAY.
STRONG PRESSURE FALLS NORTH OF LAKE SUPERIOR AND AN INCREASING
PRESSURE GRADIENT IS EXPECTED TO RESULT IN GALE FORCE SOUTHWESTERLY
WINDS OVER MUCH OF LAKE SUPERIOR ON MONDAY. A GALE WATCH REMAIN IN
EFFECT FOR THIS TIME FRAME. WINDS SETTLE DOWN BY TUESDAY WITH
WEAKENING PRESSURE GRADIENT...BUT INCREASE WEDNESDAY INTO THURSDAY
AS LOW PRESSURE SYSTEM/STRONG COLD FRONT PUSH ACROSS THE UPPER GREAT
LAKES REGION. EXACT WIND DIRECTION/SPEEDS ARE UNCERTAIN FOR
WEDNESDAY...BUT EVENTUALLY N/NW WINDS SHOULD REACH GALE OR NEAR GALE
FORCE BY THURSDAY IN WAKE OF THE LOW PRESSURE/COLD FRONT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM LATE SUNDAY NIGHT THROUGH MONDAY AFTERNOON FOR
LSZ162-263>266.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...JMW
MARINE...JLB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
120 PM CST FRI JAN 6 2012
.UPDATE...
HAVE NUDGED TEMPS UPWARD A FEW DEGREES TODAY...ESPECIALLY IN THE
SOUTHEAST CWA...TO READINGS CLOSER TO 925MB MIX-DOWN VALUES. TEMPS
CONTINUE TO RISE EASILY TODAY DESPITE CLOUD COVER...AIDED BY
MIXING ON NORTHWESTERLY WINDS. HAVE ALSO INCREASED SKY COVER FOR
THE DAY AS STUBBORN BAND OF MID-LEVEL CLOUDS WORKS THROUGH THE
AREA.
MAYES
&&
.AVIATION...
18Z TAFS FOR KOMA...KLNK...AND KOFK.
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF CYCLE. NORTHWEST WINDS
OF 12-15KT WILL DIMINISH AROUND SUNSET...THEN BECOME WEST TO
SOUTHWESTERLY OVERNIGHT. SCT-BKN MID-LEVEL CLOUDS AROUND 10-12KFT
WILL LINGER THROUGH AROUND 00Z...WITH MAINLY CLEAR SKIES
OVERNIGHT AND INTO SATURDAY.
MAYES
&&
.PREV DISCUSSION... /ISSUED 522 AM CST FRI JAN 6 2012/
AVIATION...
12Z TAFS FOR KOMA...KLNK...KOFK.
COLD FRONT MOVING INTO EXTREME SOUTHEAST NEBRASKA AT 11Z
WILL CONTINUE TO PUSH SOUTHEAST THROUGH THE PERIOD. NORTH TO
NORTHWEST WINDS INCREASING BY 18Z WITH GUSTS TO 25KT AS HIGH
PRESSURE BUILDS INTO THE AREA. WINDS DIMINISH BY 00Z. VFR
CONDITIONS THROUGH FORECAST PERIOD.
PREV DISCUSSION... /ISSUED 416 AM CST FRI JAN 6 2012/
DISCUSSION /TODAY THROUGH NEXT FRIDAY/...
GENERALLY QUIET WEATHER THROUGHOUT WITH COLDER AIR COMING THE
MIDDLE OF NEXT WEEK.
THE LATEST WV IMAGERY/400MB RUC HEIGHTS/LATEST METARS SHOWS A
SURFACE TROUGH HAS PASSED THROUGH THE COUNTY WARNING AREA. THE
ONLY NOTICEABLE AFFECT HAS BEEN AN INCREASE IN CLOUD
COVER...ALLOWING TEMPERATURES TO REMAIN MILD. BEHIND THE FRONT THE
AIRMASS IS NOTABLY COOLER WHEN COMPARED TO YESTERDAY...THOUGH
TEMPERATURES WILL NOT SIGNIFICANTLY COOL MUCH UNTIL THE MIDDLE OF
NEXT WEEK. MOST AREAS SHOULD REACH THE LOW 50S TODAY...STILL 15
DEGREES ABOVE NORMAL...DESPITE THE ADVANCE OF COLDER AIR ALOFT.
POST FRONTAL WINDS ARE ANTICIPATED TO REMAIN IN CHECK WITH
NORTHWEST WINDS GUSTING TO 25 MPH AT BEST. SO OVERALL STILL A
PRETTY NICE DAY FOR WINTER. WE DO HAVE A SLIGHT CHANCE OF SNOW
SATURDAY NIGHT INTO SUNDAY MORNING AHEAD OF A BROAD UPPER LEVEL
TROUGH SITUATED OVER THE WESTERN UNITED STATES. LATEST MODEL
GUIDANCE KEEPS THE BETTER MOISTURE ALONG WITH QG FORCING SOUTH OF
THE PLATTE RIVER IN THE SOUTHWESTERN PORTIONS OF THE COUNTY
WARNING AREA. WE WILL BE HARD PRESSED TO SEE MUCH OF ANY
ACCUMULATIONS FROM THESE SNOW SHOWERS AS THE BEST FORCING IS WELL
OFF TO OUR WEST. THIS FEATURE SHIFTS SOUTH AND EAST THROUGHOUT THE
DAY ON SUNDAY. BEHIND IT THE WEATHER LOOKS QUIET AND DRY. BY
WEDNESDAY A MORE WINTERTIME AIRMASS WILL DIVE INTO THE PLAINS FROM
CANADA. 850MB AIRMASS TEMPERATURES OF -10 TO -13C WILL SUPPORT
HIGHS IN THE UPPER TEENS AND LOW 20S ALLOWING HIGH TEMPERATURES TO
DROP BELOW NORMAL FOR A CHANGE.
CLIMATE...
HERE IS A SUMMARY OF THE RECORDS BROKEN YESTERDAY.
AT 354 PM CST THE TEMPERATURE REACHED 66 DEGREES AT OMAHA EPPLEY
AIRFIELD. THIS BROKE THE OLD RECORD HIGH OF 62 DEGREES WHICH WAS SET
IN 1956.
AT 346 PM CST THE TEMPERATURE REACHED 68 DEGREES AT THE LINCOLN
AIRPORT. THIS BROKE THE PREVIOUS RECORD HIGH OF 61 DEGREES WHICH WAS
SET IN 1956.
AT 351 PM CST...THE TEMPERATURE REACHED 70 DEGREES AT THE NORFOLK
AIRPORT. THIS BROKE THE PREVIOUS RECORD HIGH OF 55 DEGREES WHICH WAS
SET IN 1956.
AVIATION...
06Z TAFS FOR KOMA...KLNK...KOFK
A COLD FRONT WILL CONTINUE TO PUSH THROUGH THE AREA OVERNIGHT...
SWITCHING WINDS TO THE NORTHWEST. WINDS SHOULD MAINLY BE LESS
THAN 10 KNOTS THROUGH MID MORNING FRIDAY. NORTHWEST WINDS WILL
BE INCREASING BY ABOUT MID DAY FRIDAY AND COULD BE A BIT GUSTY
THROUGH THE AFTERNOON. EXPECT VFR CONDITIONS THROUGH THE NEXT
24 HOURS...WITH ANY CLOUDS GENERALLY ABOVE 8000 FEET.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
522 AM CST FRI JAN 6 2012
.AVIATION...
12Z TAFS FOR KOMA...KLNK...KOFK.
COLD FRONT MOVING INTO EXTREME SOUTHEAST NEBRASKA AT 11Z
WILL CONTINUE TO PUSH SOUTHEAST THROUGH THE PERIOD. NORTH TO
NORTHWEST WINDS INCREASING BY 18Z WITH GUSTS TO 25KT AS HIGH
PRESSURE BUILDS INTO THE AREA. WINDS DIMINISH BY 00Z. VFR
CONDITIONS THROUGH FORECAST PERIOD.
&&
.PREV DISCUSSION... /ISSUED 416 AM CST FRI JAN 6 2012/
DISCUSSION /TODAY THROUGH NEXT FRIDAY/...
GENERALLY QUIET WEATHER THROUGHOUT WITH COLDER AIR COMING THE
MIDDLE OF NEXT WEEK.
THE LATEST WV IMAGERY/400MB RUC HEIGHTS/LATEST METARS SHOWS A
SURFACE TROUGH HAS PASSED THROUGH THE COUNTY WARNING AREA. THE
ONLY NOTICEABLE AFFECT HAS BEEN AN INCREASE IN CLOUD
COVER...ALLOWING TEMPERATURES TO REMAIN MILD. BEHIND THE FRONT THE
AIRMASS IS NOTABLY COOLER WHEN COMPARED TO YESTERDAY...THOUGH
TEMPERATURES WILL NOT SIGNIFICANTLY COOL MUCH UNTIL THE MIDDLE OF
NEXT WEEK. MOST AREAS SHOULD REACH THE LOW 50S TODAY...STILL 15
DEGREES ABOVE NORMAL...DESPITE THE ADVANCE OF COLDER AIR ALOFT.
POST FRONTAL WINDS ARE ANTICIPATED TO REMAIN IN CHECK WITH
NORTHWEST WINDS GUSTING TO 25 MPH AT BEST. SO OVERALL STILL A
PRETTY NICE DAY FOR WINTER. WE DO HAVE A SLIGHT CHANCE OF SNOW
SATURDAY NIGHT INTO SUNDAY MORNING AHEAD OF A BROAD UPPER LEVEL
TROUGH SITUATED OVER THE WESTERN UNITED STATES. LATEST MODEL
GUIDANCE KEEPS THE BETTER MOISTURE ALONG WITH QG FORCING SOUTH OF
THE PLATTE RIVER IN THE SOUTHWESTERN PORTIONS OF THE COUNTY
WARNING AREA. WE WILL BE HARD PRESSED TO SEE MUCH OF ANY
ACCUMULATIONS FROM THESE SNOW SHOWERS AS THE BEST FORCING IS WELL
OFF TO OUR WEST. THIS FEATURE SHIFTS SOUTH AND EAST THROUGHOUT THE
DAY ON SUNDAY. BEHIND IT THE WEATHER LOOKS QUIET AND DRY. BY
WEDNESDAY A MORE WINTERTIME AIRMASS WILL DIVE INTO THE PLAINS FROM
CANADA. 850MB AIRMASS TEMPERATURES OF -10 TO -13C WILL SUPPORT
HIGHS IN THE UPPER TEENS AND LOW 20S ALLOWING HIGH TEMPERATURES TO
DROP BELOW NORMAL FOR A CHANGE.
CLIMATE...
HERE IS A SUMMARY OF THE RECORDS BROKEN YESTERDAY.
AT 354 PM CST THE TEMPERATURE REACHED 66 DEGREES AT OMAHA EPPLEY
AIRFIELD. THIS BROKE THE OLD RECORD HIGH OF 62 DEGREES WHICH WAS SET
IN 1956.
AT 346 PM CST THE TEMPERATURE REACHED 68 DEGREES AT THE LINCOLN
AIRPORT. THIS BROKE THE PREVIOUS RECORD HIGH OF 61 DEGREES WHICH WAS
SET IN 1956.
AT 351 PM CST...THE TEMPERATURE REACHED 70 DEGREES AT THE NORFOLK
AIRPORT. THIS BROKE THE PREVIOUS RECORD HIGH OF 55 DEGREES WHICH WAS
SET IN 1956.
AVIATION...
06Z TAFS FOR KOMA...KLNK...KOFK
A COLD FRONT WILL CONTINUE TO PUSH THROUGH THE AREA OVERNIGHT...
SWITCHING WINDS TO THE NORTHWEST. WINDS SHOULD MAINLY BE LESS
THAN 10 KNOTS THROUGH MID MORNING FRIDAY. NORTHWEST WINDS WILL
BE INCREASING BY ABOUT MID DAY FRIDAY AND COULD BE A BIT GUSTY
THROUGH THE AFTERNOON. EXPECT VFR CONDITIONS THROUGH THE NEXT
24 HOURS...WITH ANY CLOUDS GENERALLY ABOVE 8000 FEET.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
FOBERT
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
416 AM CST FRI JAN 6 2012
.DISCUSSION /TODAY THROUGH NEXT FRIDAY/...
GENERALLY QUIET WEATHER THROUGHOUT WITH COLDER AIR COMING THE
MIDDLE OF NEXT WEEK.
THE LATEST WV IMAGERY/400MB RUC HEIGHTS/LATEST METARS SHOWS A
SURFACE TROUGH HAS PASSED THROUGH THE COUNTY WARNING AREA. THE
ONLY NOTICEABLE AFFECT HAS BEEN AN INCREASE IN CLOUD
COVER...ALLOWING TEMPERATURES TO REMAIN MILD. BEHIND THE FRONT THE
AIRMASS IS NOTABLY COOLER WHEN COMPARED TO YESTERDAY...THOUGH
TEMPERATURES WILL NOT SIGNIFICANTLY COOL MUCH UNTIL THE MIDDLE OF
NEXT WEEK. MOST AREAS SHOULD REACH THE LOW 50S TODAY...STILL 15
DEGREES ABOVE NORMAL...DESPITE THE ADVANCE OF COLDER AIR ALOFT.
POST FRONTAL WINDS ARE ANTICIPATED TO REMAIN IN CHECK WITH
NORTHWEST WINDS GUSTING TO 25 MPH AT BEST. SO OVERALL STILL A
PRETTY NICE DAY FOR WINTER. WE DO HAVE A SLIGHT CHANCE OF SNOW
SATURDAY NIGHT INTO SUNDAY MORNING AHEAD OF A BROAD UPPER LEVEL
TROUGH SITUATED OVER THE WESTERN UNITED STATES. LATEST MODEL
GUIDANCE KEEPS THE BETTER MOISTURE ALONG WITH QG FORCING SOUTH OF
THE PLATTE RIVER IN THE SOUTHWESTERN PORTIONS OF THE COUNTY
WARNING AREA. WE WILL BE HARD PRESSED TO SEE MUCH OF ANY
ACCUMULATIONS FROM THESE SNOW SHOWERS AS THE BEST FORCING IS WELL
OFF TO OUR WEST. THIS FEATURE SHIFTS SOUTH AND EAST THROUGHOUT THE
DAY ON SUNDAY. BEHIND IT THE WEATHER LOOKS QUIET AND DRY. BY
WEDNESDAY A MORE WINTERTIME AIRMASS WILL DIVE INTO THE PLAINS FROM
CANADA. 850MB AIRMASS TEMPERATURES OF -10 TO -13C WILL SUPPORT
HIGHS IN THE UPPER TEENS AND LOW 20S ALLOWING HIGH TEMPERATURES TO
DROP BELOW NORMAL FOR A CHANGE.
&&
.CLIMATE...
HERE IS A SUMMARY OF THE RECORDS BROKEN YESTERDAY.
AT 354 PM CST THE TEMPERATURE REACHED 66 DEGREES AT OMAHA EPPLEY
AIRFIELD. THIS BROKE THE OLD RECORD HIGH OF 62 DEGREES WHICH WAS SET
IN 1956.
AT 346 PM CST THE TEMPERATURE REACHED 68 DEGREES AT THE LINCOLN
AIRPORT. THIS BROKE THE PREVIOUS RECORD HIGH OF 61 DEGREES WHICH WAS
SET IN 1956.
AT 351 PM CST...THE TEMPERATURE REACHED 70 DEGREES AT THE NORFOLK
AIRPORT. THIS BROKE THE PREVIOUS RECORD HIGH OF 55 DEGREES WHICH WAS
SET IN 1956.
&&
.AVIATION...
06Z TAFS FOR KOMA...KLNK...KOFK
A COLD FRONT WILL CONTINUE TO PUSH THROUGH THE AREA OVERNIGHT...
SWITCHING WINDS TO THE NORTHWEST. WINDS SHOULD MAINLY BE LESS
THAN 10 KNOTS THROUGH MID MORNING FRIDAY. NORTHWEST WINDS WILL
BE INCREASING BY ABOUT MID DAY FRIDAY AND COULD BE A BIT GUSTY
THROUGH THE AFTERNOON. EXPECT VFR CONDITIONS THROUGH THE NEXT
24 HOURS...WITH ANY CLOUDS GENERALLY ABOVE 8000 FEET.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
DISCUSSION/CLIMATE...PEARSON
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
541 PM EST FRI JAN 6 2012
.SYNOPSIS...
A WARM FRONT WILL PUSH NORTH ACROSS THE REGION TONIGHT. A COLD
FRONT WILL THEN MOVE SOUTHEAST ACROSS THE AREA SATURDAY AFTERNOON AND
EVENING...ACCOMPANIED BY SCATTERED RAIN AND SNOW SHOWERS. HIGH
PRESSURE WILL BUILD INTO THE NORTH COUNTRY ON SUNDAY. TEMPERATURES
WILL BE WELL ABOVE NORMAL ON SATURDAY...THEN RETURN TO NORMAL
LEVELS SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 541 PM EST FRIDAY...OVERALL FORECAST IN GOOD SHAPE WITH JUST
A TWEAK OF HOURLY TEMPERATURES TONIGHT. LOW LEVEL NORTHEAST WINDS
IN THE SAINT LAWRENCE VALLEY CONTINUE TO DRAIN SOUTHWEST AND THIS
HAS KEPT TEMPERATURES IN THE UPPER TEENS TO LOWER 20S...SO HAVE
ADJUSTED HOURLY TEMPERATURES TO DELAY ANY WARMING UNTIL LATER
TONIGHT. AT THE SAME TIME...PLENTY OF CLOUD COVER ELSEWHERE OVER
THE AREA IS HELPING TO HOLD TEMPERATURES FAIRLY STEADY AND HAVE
ADJUSTED TEMPERATURE GRIDS TO ACCOUNT FOR MINIMAL DIURNAL TREND
OVERNIGHT. THIS IS MOST PRONOUNCED OVER THE NORTHEAST KINGDOM
WHERE MODEL TEMPERATURES ALWAYS WANT TO COOL THINGS DOWN...BUT
CLOUDS WILL LIMIT THAT. REMAINDER OF FORECAST IN REAL GOOD SHAPE
AND NO OTHER CHANGES NEEDED AT THIS TIME.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 340 PM EST FRIDAY...LOW PRESSURE CONTINUES TO MAKE ITS WAY
EAST ACROSS SOUTHERN QUEBEC ON SATURDAY. PRE-FONTAL TROUGH MOVES
ACROSS FORECAST AREA DURING THE DAY ON SATURDAY...BUT ACTUAL COLD
FRONT DOESN`T DROP SOUTH ACROSS FORECAST AREA TILL SATURDAY NIGHT.
EXPECT SCATTERED RAIN/SNOW SHOWERS SATURDAY...MAINLY OVER THE
HIGHER TERRAIN OF NORTHERN ZONES. WHILE WARMEST AIR WILL REMAIN
SOUTH OF FORECAST AREA...MAX TEMPS ACROSS BTV CWA WILL BE WELL ABOVE
NORMAL WITH HIGHS IN THE 40S...PERHAPS APPROACHING 50 SOUTHERN AREAS.
SCATTERED SNOW SHOWERS SATURDAY NIGHT AS COLD FRONT AND MID LEVEL
SHORTWAVE MOVE ACROSS THE REGION . AGAIN THE BETTER CHANCE FOR
SEEING PRECIPITATION WILL BE OVER NORTHERN ZONES...AND THERE MAY BE
SOME LIGHT SNOW ACCUMULATIONS...ESPECIALLY OVER THE HIGHER TERRAIN.
HIGH PRESSURE BUILDS INTO THE REGION ON SUNDAY WITH MAINLY DRY
CONDITIONS AND COLDER TEMPERATURES WITH HIGHS AROUND NORMAL LEVELS.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 230 PM EST FRIDAY...THE SYSTEM FOR LATE WEDS INTO THURS OF
THIS UPCOMING WEEK...LOOKS VERY SIMILAR TO THE DEC 27-28TH EVENT
WITH THE ASSOCIATED SFC LOW PRES TRACK AND POSITION OF MID/UPPER
LVL TROF. THE INITIAL SURGE OF MOISTURE/LIFT WL IMPACT OUR CWA LATE
WEDS NIGHT...WITH A MIX CHANGING TO RAIN...THEN BACK TO SNOW AS
COLDER AIR RACES ACRS OUR CWA ON THURS. LIKE THE DEC 28TH EVENT A
FLASH FREEZE WL BE POSSIBLE...ALONG WITH A PERIOD OF ACCUMULATING
UPSLOPE SNOW ON THURS AFTN/EVENING.
POTENT MID/UPPER LVL CIRCULATION WL EJECT FOR SW CONUS ON TUES
INTO WEDS...WITH SFC LOW PRES TRACKING ALONG THE GULF COAST
STATES...THEN MOVING ACRS THE APPALACHIAN MTNS TWD THE MID
ATLANTIC STATES BY THURS. THIS SYSTEM WL ADVECT PLENTY OF MOISTURE
INTO OUR CWA...AS PWS VALUES APPROACH 1.0". THIS
MOISTURE...COMBINED WITH POTENT S/W ENERGY AND NOSE OF STRONG LLVL
JET WL HELP IN THE DEVELOPMENT OF PRECIP FROM SOUTH TO NORTH ACRS
OUR REGION LATE WEDS INTO THURS. SE FLW ASSOCIATED WITH INITIAL
SURGE OF MOISTURE...WL PRODUCE SOME SHADOWING EFFECTS ACRS THE
EASTERN CPV AND PARTS OF THE NEK...WHICH COMBINED WITH FAST
MOVEMENT OF SYSTEM WL LIMIT DURATION OF PRECIP. MEANWHILE...AS
SFC LOW PRES TRACKS INTO SOUTHERN CANADA...STRONG LLVL CAA WL
DEVELOP ON THURS AFTN...AND TEMPS WL FALL. THESE FALLING TEMPS ON
NW UPSLOPE FLW WL INTERACT WITH NORTHERN STREAM ENERGY AND
MOISTURE TO PRODUCE A PERIOD OF SNOW SHOWERS. SOME ACCUMULATION
CAN BE ANTICIPATED...ESPECIALLY ACRS THE NORTHERN DACKS AND PARTS
OF THE CENTRAL/NORTHERN GREEN MTNS. COOLER AND DRIER WX WL RETURN
FOR FRIDAY WITH SOME MTN SNOW SHOWERS POSSIBLE.
OTHERWISE...MONDAY AND TUES OF THIS UPCOMING WEEK WL BE
RELATIVELY QUIET WITH ABOVE NORMAL TEMPS AND ONLY SLIGHT CHANCES
FOR SCATTERED MAINLY MTN SNOW SHOWERS...ASSOCIATED WITH NORTHERN
STREAM ENERGY/MOISTURE.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...A SURFACE WARM FRNT CONTS TO PRODUCE PLENTY
OF CLOUDS ACRS OUR TAF SITES THIS AFTN...WITH RADAR SHOWING JUST A
FEW FLURRIES. VIS SATL PIC SHOWS CLRING SKIES ACRS CENTRAL
NY...TRYING TO MOVE TWD OUR REGION THIS AFTN. TAF CHALLENGE WL BE
AMOUNT OF LLVL MOISTURE AND POTENTIAL FOR MVFR/IFR CONDITIONS
TONIGHT. RUC AND NAM SOUNDINGS SHOW PLENTY OF LLVL MOISTURE
DEVELOPING AFT 00Z THIS EVENING AS WARM AIR MOVES ACRS THE
RELATIVELY COLD/SNOW COVERED GROUND. IN ADDITION...SOME MELTING WL
ALSO ADD TO THE MOISTURE IN THE BL. WL MENTION MVFR CIGS AT MOST
TAF SITES...WITH BEST POTENTIAL FOR IFR AT MPV/SLK/MSS. AT MSS NE
SFC WINDS WL SHIFT TO THE SW BY 03Z THIS EVENING...AS SFC WARM
FRNT FINALLY LIFTS THRU THE SLV. ALSO...PATCHY AREAS OF
DRIZZLE/FREEZING DRIZZLE WL BE POSSIBLE...GIVEN AMOUNT OF LLVL
MOISTURE PROGGED TO BE ACRS OUR MTN SITES...BUT NO ICE
ACCUMULATION IS ANTICIPATING. IMPROVING CONDITIONS WL DEVELOP BY
14Z SATURDAY...WITH SOUTHERLY FLW OF 5 TO 15 KNTS.
OUTLOOK 18Z SATURDAY THROUGH TUESDAY...
ON SATURDAY EVENING A SURFACE COLD FRNT WL PRODUCE SCATTERED RAIN
AND SNOW SHOWERS...WHICH WL CHANGE TO ALL SNOW BY LATE EVENING.
OCCASIONAL IFR CONDITIONS FOR SEVERAL HRS WL BE POSSIBLE ON SAT
NIGHT INTO SUNDAY...ESPECIALLY AT MPV/SLK. OTHERWISE...SFC HIGH PRES
AND VFR CONDITIONS WL PREVAIL SUNDAY AFTN THRU TUESDAY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...RJS
NEAR TERM...EVENSON/RJS
SHORT TERM...RJS
LONG TERM...TABER
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
342 PM EST FRI JAN 6 2012
.SYNOPSIS...
A WARM FRONT WILL PUSH NORTH ACROSS THE REGION TONIGHT. A COLD
FRONT WILL THEN MOVE SOUTHEAST ACROSS THE AREA SATURDAY AFTERNOON AND
EVENING...ACCOMPANIED BY SCATTERED RAIN AND SNOW SHOWERS. HIGH
PRESSURE WILL BUILD INTO THE NORTH COUNTRY ON SUNDAY. TEMPERATURES
WILL BE WELL ABOVE NORMAL ON SATURDAY...THEN RETURN TO NORMAL
LEVELS SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 340 PM EST FRIDAY...LOW PRESSURE LOCATED NORTH OF THE GREAT
LAKES WILL TRACK SLOWLY EAST TONIGHT. WARM FRONT ASSOCIATED WITH THE
LOW WILL CONTINUE TO MAKE ITS WAY NORTHEAST ACROSS THE FORECAST
AREA. LITTLE IF ANY PRECIPITATION BEING DETECTED ACROSS FORECAST
AREA AT THIS TIME...AND EXPECT THIS TO REMAIN THE CASE TONIGHT
AS FORCING WEAK AND DEEP LAYER MOISTURE LIMITED. SOME SPOTTY
LIGHT PRECIPITATION IS POSSIBLE...ESPECIALLY NORTHERN AREAS...AND
IT COULD BE IN FORM OF FLURRIES OR SNOW GRAINS...DRIZZLE OR FREEZING
DRIZZLE. TEMPERATURES THIS AFTERNOON RANGE FROM THE UPPER TEENS IN
NORTHERN SAINT LAWRENCE VALLEY TO THE UPPER 30S IN SOUTHERN
PORTIONS OF FORECAST AREA. EXPECT RATHER STEADY TEMPERATURES
CENTRAL AND SOUTHERN SECTIONS TONIGHT...WITH READINGS RISING OVER
THE FAR NORTH AS LOW LEVEL COLD AIR IS GRADUALLY SCOURED OUT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
AS OF 340 PM EST FRIDAY...LOW PRESSURE CONTINUES TO MAKE ITS WAY
EAST ACROSS SOUTHERN QUEBEC ON SATURDAY. PREFRONTAL TROUGH MOVES
ACROSS FORECAST AREA DURING THE DAY ON SATURDAY...BUT ACTUAL COLD
FRONT DOESN`T DROP SOUTH ACROSS FORECAST AREA TILL SATURDAY NIGHT.
EXPECT SCATTERED RAIN/SNOW SHOWERS SATURDAY...MAINLY OVER THE
HIGHER TERRAIN OF NORTHERN ZONES. WHILE WARMEST AIR WILL REMAIN
SOUTH OF FORECAST AREA...MAX TEMPS ACROSS BTV CWA WILL BE WELL ABOVE
NORMAL WITH HIGHS IN THE 40S...PERHAPS APPROACHING 50 SOUTHERN AREAS.
SCATTERED SNOW SHOWERS SATURDAY NIGHT AS COLD FRONT AND MID LEVEL
SHORTWAVE MOVE ACROSS THE REGION . AGAIN THE BETTER CHANCE FOR
SEEING PRECIPITATION WILL BE OVER NORTHERN ZONES...AND THERE MAY BE
SOME LIGHT SNOW ACCUMULATIONS...ESPECIALLY OVER THE HIGHER TERRAIN.
HIGH PRESSURE BUILDS INTO THE REGION ON SUNDAY WITH MAINLY DRY
CONDITIONS AND COLDER TEMPERATURES WITH HIGHS AROUND NORMAL LEVELS.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 230 PM EST FRIDAY...THE SYSTEM FOR LATE WEDS INTO THURS OF
THIS UPCOMING WEEK...LOOKS VERY SIMILAR TO THE DEC 27-28TH EVENT
WITH THE ASSOCIATED SFC LOW PRES TRACK AND POSITION OF MID/UPPER
LVL TROF. THE INITIAL SURGE OF MOISTURE/LIFT WL IMPACT OUR CWA LATE
WEDS NIGHT...WITH A MIX CHANGING TO RAIN...THEN BACK TO SNOW AS
COLDER AIR RACES ACRS OUR CWA ON THURS. LIKE THE DEC 28TH EVENT A
FLASH FREEZE WL BE POSSIBLE...ALONG WITH A PERIOD OF ACCUMULATING
UPSLOPE SNOW ON THURS AFTN/EVENING.
POTENT MID/UPPER LVL CIRCULATION WL EJECT FOR SW CONUS ON TUES
INTO WEDS...WITH SFC LOW PRES TRACKING ALONG THE GULF COAST
STATES...THEN MOVING ACRS THE APPALACHIAN MTNS TWD THE MID
ATLANTIC STATES BY THURS. THIS SYSTEM WL ADVECT PLENTY OF MOISTURE
INTO OUR CWA...AS PWS VALUES APPROACH 1.0". THIS
MOISTURE...COMBINED WITH POTENT S/W ENERGY AND NOSE OF STRONG LLVL
JET WL HELP IN THE DEVELOPMENT OF PRECIP FROM SOUTH TO NORTH ACRS
OUR REGION LATE WEDS INTO THURS. SE FLW ASSOCIATED WITH INITIAL
SURGE OF MOISTURE...WL PRODUCE SOME SHADOWING EFFECTS ACRS THE
EASTERN CPV AND PARTS OF THE NEK...WHICH COMBINED WITH FAST
MOVEMENT OF SYSTEM WL LIMIT DURATION OF PRECIP. MEANWHILE...AS
SFC LOW PRES TRACKS INTO SOUTHERN CANADA...STRONG LLVL CAA WL
DEVELOP ON THURS AFTN...AND TEMPS WL FALL. THESE FALLING TEMPS ON
NW UPSLOPE FLW WL INTERACT WITH NORTHERN STREAM ENERGY AND
MOISTURE TO PRODUCE A PERIOD OF SNOW SHOWERS. SOME ACCUMULATION
CAN BE ANTICIPATED...ESPECIALLY ACRS THE NORTHERN DACKS AND PARTS
OF THE CENTRAL/NORTHERN GREEN MTNS. COOLER AND DRIER WX WL RETURN
FOR FRIDAY WITH SOME MTN SNOW SHOWERS POSSIBLE.
OTHERWISE...MONDAY AND TUES OF THIS UPCOMING WEEK WL BE
RELATIVELY QUIET WITH ABOVE NORMAL TEMPS AND ONLY SLIGHT CHANCES
FOR SCATTERED MAINLY MTN SNOW SHOWERS...ASSOCIATED WITH NORTHERN
STREAM ENERGY/MOISTURE.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...A SURFACE WARM FRNT CONTS TO PRODUCE PLENTY
OF CLOUDS ACRS OUR TAF SITES THIS AFTN...WITH RADAR SHOWING JUST A
FEW FLURRIES. VIS SATL PIC SHOWS CLRING SKIES ACRS CENTRAL
NY...TRYING TO MOVE TWD OUR REGION THIS AFTN. TAF CHALLENGE WL BE
AMOUNT OF LLVL MOISTURE AND POTENTIAL FOR MVFR/IFR CONDITIONS
TONIGHT. RUC AND NAM SOUNDINGS SHOW PLENTY OF LLVL MOISTURE
DEVELOPING AFT 00Z THIS EVENING AS WARM AIR MOVES ACRS THE
RELATIVELY COLD/SNOW COVERED GROUND. IN ADDITION...SOME MELTING WL
ALSO ADD TO THE MOISTURE IN THE BL. WL MENTION MVFR CIGS AT MOST
TAF SITES...WITH BEST POTENTIAL FOR IFR AT MPV/SLK/MSS. AT MSS NE
SFC WINDS WL SHIFT TO THE SW BY 03Z THIS EVENING...AS SFC WARM
FRNT FINALLY LIFTS THRU THE SLV. ALSO...PATCHY AREAS OF
DRIZZLE/FREEZING DRIZZLE WL BE POSSIBLE...GIVEN AMOUNT OF LLVL
MOISTURE PROGGED TO BE ACRS OUR MTN SITES...BUT NO ICE
ACCUMULATION IS ANTICIPATING. IMPROVING CONDITIONS WL DEVELOP BY
14Z SATURDAY...WITH SOUTHERLY FLW OF 5 TO 15 KNTS.
OUTLOOK 18Z SATURDAY THROUGH TUESDAY...
ON SATURDAY EVENING A SURFACE COLD FRNT WL PRODUCE SCATTERED RAIN
AND SNOW SHOWERS...WHICH WL CHANGE TO ALL SNOW BY LATE EVENING.
OCCASIONAL IFR CONDITIONS FOR SEVERAL HRS WL BE POSSIBLE ON SAT
NIGHT INTO SUNDAY...ESPECIALLY AT MPV/SLK. OTHERWISE...SFC HIGH PRES
AND VFR CONDITIONS WL PREVAIL SUNDAY AFTN THRU TUESDAY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...RJS
NEAR TERM...RJS
SHORT TERM...RJS
LONG TERM...TABER
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
236 PM EST FRI JAN 6 2012
.SYNOPSIS...
A WARM FRONT PUSHING THROUGH THE NORTHEAST WILL CONTINUE TO
PROVIDE SOME LIGHT SNOW TO THE NORTH COUNTRY TODAY. MAINLY DRY
WEATHER IS EXPECTED FOR THE WEEKEND...THOUGH SOME PERIODS OF
LIGHT PRECIPITATION ARE POSSIBLE ACROSS NORTHERN PORTIONS OF THE
AREA TONIGHT THROUGH SATURDAY AS A CLIPPER SYSTEM PASSES NORTH OF
THE BORDER. TEMPERATURES WILL MODERATE TO ABOVE NORMAL LEVELS
TODAY AND SATURDAY...AND RETURN BACK TO NORMAL FOR SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1244 PM EST FRIDAY...ALL STEADY LIGHT SNOW HAS COME TO AN END
ACROSS THE REGION WITH THIS MORNINGS SNOW LEAVING BEHIND A HALF
INCH TO LOCALLY TWO INCHES OF ACCUMULATION. HOWEVER WITH LINGERING
MOISTURE AND A WARM FRONTAL BOUNDARY REMAINING DRAPED ACROSS THE
AREA THIS AFTERNOON...WIDESPREAD CLOUDS AND POCKETS OF LIGHT
PRECIPITATION REMAIN. SOME ISOLATED AREAS OF LIGHT PRECIPITATION
AND MIST WILL LIKELY CONTINUE ACROSS THE HIGHER ELEVATIONS BUT
AMOUNTS WILL BE VERY LIGHT. WITH WARMING LOW LEVELS AND SHALLOW
MOISTURE...THE PRECIPITATION WILL FALL IN THE FORM OF A LIGHT
DRIZZLE OR FREEZING DRIZZLE WITH A FLURRY OR TWO POSSIBLE. OVERALL
NOT A BIG DEAL BUT A VERY LIGHT GLAZE OF ICE POSSIBLE ON SOME SURFACES.
MOST OF THE REGION WILL REMAIN DRY. TEMPERATURES WILL RISE THROUGH
THE DAY WITH HIGHS LATE IN THE AFTERNOON CLIMBING INTO THE 30S IN
MOST LOCATIONS. SEEING A LOW LEVEL JET PASSING THROUGH THE REGION
CURRENTLY...SO SOME 20 KNOT GUSTS WILL BE SEEN THIS AFTERNOON...ESPECIALLY
IN THE CHAMPLAIN VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
AS OF 406 AM EST FRIDAY...CHANCES FOR SOME INTERMITTENT LIGHT
SNOW SHOWERS WILL CONTINUE TONIGHT AS THE SURFACE LOW TRACKS
NORTH OF THE BORDER...THOUGH WILL BE MAINLY CONFINED AGAIN TO THE
NORTHERN ZONES. THE REGION REMAINS UNDER CLOUDY SKIES AND
SOUTH/SOUTHWEST FLOW SO EXPECT OVERNIGHT TEMPS TO BE QUITE
MILD...MAINLY IN THE MID TO UPPER 20S. ATTENDING COLD FRONT WILL
PUSH THROUGH THE REGION SATURDAY AFTERNOON AND EVENING...WITH
CONTINUE CHANCES FOR LIGHT PRECIPITATION. PTYPE FOR SATURDAY WILL
BE MAINLY RAIN WITH SOME SNOW TO START THE DAY AS TEMPS AGAIN WILL
BE WELL ABOVE NORMAL WITH MOST LOCATIONS WARMING INTO THE UPPER
30S TO LOWER 40S. IN ADDITION...SOUTHWEST FLOW AHEAD OF THE FRONT
WILL PROVIDE THE POTENTIAL FOR SOME LAKE ENHANCED PRECIP DOWNWIND
OF LAKE ONTARIO...THOUGH PROBABLY WON`T BE LONG LIVED AS HIGH
PRESSURE WILL BEGIN TO BUILD INTO THE REGION LATE SATURDAY NIGHT
INTO SUNDAY. DRY CONDITIONS AND MORE SEASONABLE TEMPERATURES ARE
EXPECTED FOR SUNDAY.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 230 PM EST FRIDAY...THE SYSTEM FOR LATE WEDS INTO THURS OF
THIS UPCOMING WEEK...LOOKS VERY SIMILAR TO THE DEC 27-28TH EVENT
WITH THE ASSOCIATED SFC LOW PRES TRACK AND POSITION OF MID/UPPER
LVL TROF. THE INITIAL SURGE OF MOISTURE/LIFT WL IMPACT OUR CWA LATE
WEDS NIGHT...WITH A MIX CHANGING TO RAIN...THEN BACK TO SNOW AS
COLDER AIR RACES ACRS OUR CWA ON THURS. LIKE THE DEC 28TH EVENT A
FLASH FREEZE WL BE POSSIBLE...ALONG WITH A PERIOD OF ACCUMULATING
UPSLOPE SNOW ON THURS AFTN/EVENING.
POTENT MID/UPPER LVL CIRCULATION WL EJECT FOR SW CONUS ON TUES
INTO WEDS...WITH SFC LOW PRES TRACKING ALONG THE GULF COAST
STATES...THEN MOVING ACRS THE APPALACHIAN MTNS TWD THE MID
ATLANTIC STATES BY THURS. THIS SYSTEM WL ADVECT PLENTY OF MOISTURE
INTO OUR CWA...AS PWS VALUES APPROACH 1.0". THIS
MOISTURE...COMBINED WITH POTENT S/W ENERGY AND NOSE OF STRONG LLVL
JET WL HELP IN THE DEVELOPMENT OF PRECIP FROM SOUTH TO NORTH ACRS
OUR REGION LATE WEDS INTO THURS. SE FLW ASSOCIATED WITH INITIAL
SURGE OF MOISTURE...WL PRODUCE SOME SHADOWING EFFECTS ACRS THE
EASTERN CPV AND PARTS OF THE NEK...WHICH COMBINED WITH FAST
MOVEMENT OF SYSTEM WL LIMIT DURATION OF PRECIP. MEANWHILE...AS
SFC LOW PRES TRACKS INTO SOUTHERN CANADA...STRONG LLVL CAA WL
DEVELOP ON THURS AFTN...AND TEMPS WL FALL. THESE FALLING TEMPS ON
NW UPSLOPE FLW WL INTERACT WITH NORTHERN STREAM ENERGY AND
MOISTURE TO PRODUCE A PERIOD OF SNOW SHOWERS. SOME ACCUMULATION
CAN BE ANTICIPATED...ESPECIALLY ACRS THE NORTHERN DACKS AND PARTS
OF THE CENTRAL/NORTHERN GREEN MTNS. COOLER AND DRIER WX WL RETURN
FOR FRIDAY WITH SOME MTN SNOW SHOWERS POSSIBLE.
OTHERWISE...MONDAY AND TUES OF THIS UPCOMING WEEK WL BE
RELATIVELY QUIET WITH ABOVE NORMAL TEMPS AND ONLY SLIGHT CHANCES
FOR SCATTERED MAINLY MTN SNOW SHOWERS...ASSOCIATED WITH NORTHERN
STREAM ENERGY/MOISTURE.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...A SURFACE WARM FRNT CONTS TO PRODUCE PLENTY
OF CLOUDS ACRS OUR TAF SITES THIS AFTN...WITH RADAR SHOWING JUST A
FEW FLURRIES. VIS SATL PIC SHOWS CLRING SKIES ACRS CENTRAL
NY...TRYING TO MOVE TWD OUR REGION THIS AFTN. TAF CHALLENGE WL BE
AMOUNT OF LLVL MOISTURE AND POTENTIAL FOR MVFR/IFR CONDITIONS
TONIGHT. RUC AND NAM SOUNDINGS SHOW PLENTY OF LLVL MOISTURE
DEVELOPING AFT 00Z THIS EVENING AS WARM AIR MOVES ACRS THE
RELATIVELY COLD/SNOW COVERED GROUND. IN ADDITION...SOME MELTING WL
ALSO ADD TO THE MOISTURE IN THE BL. WL MENTION MVFR CIGS AT MOST
TAF SITES...WITH BEST POTENTIAL FOR IFR AT MPV/SLK/MSS. AT MSS NE
SFC WINDS WL SHIFT TO THE SW BY 03Z THIS EVENING...AS SFC WARM
FRNT FINALLY LIFTS THRU THE SLV. ALSO...PATCHY AREAS OF
DRIZZLE/FREEZING DRIZZLE WL BE POSSIBLE...GIVEN AMOUNT OF LLVL
MOISTURE PROGGED TO BE ACRS OUR MTN SITES...BUT NO ICE
ACCUMULATION IS ANTICIPATING. IMPROVING CONDITIONS WL DEVELOP BY
14Z SATURDAY...WITH SOUTHERLY FLW OF 5 TO 15 KNTS.
OUTLOOK 18Z SATURDAY THROUGH TUESDAY...
ON SATURDAY EVENING A SURFACE COLD FRNT WL PRODUCE SCATTERED RAIN
AND SNOW SHOWERS...WHICH WL CHANGE TO ALL SNOW BY LATE EVENING.
OCCASIONAL IFR CONDITIONS FOR SEVERAL HRS WL BE POSSIBLE ON SAT
NIGHT INTO SUNDAY...ESPECIALLY AT MPV/SLK. OTHERWISE...SFC HIGH PRES
AND VFR CONDITIONS WL PREVAIL SUNDAY AFTN THRU TUESDAY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...MUCCILLI
SHORT TERM...LAHIFF
LONG TERM...TABER
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1245 PM EST FRI JAN 6 2012
.SYNOPSIS...
A WARM FRONT PUSHING THROUGH THE NORTHEAST WILL CONTINUE TO
PROVIDE SOME LIGHT SNOW TO THE NORTH COUNTRY TODAY. MAINLY DRY
WEATHER IS EXPECTED FOR THE WEEKEND...THOUGH SOME PERIODS OF
LIGHT PRECIPITATION ARE POSSIBLE ACROSS NORTHERN PORTIONS OF THE
AREA TONIGHT THROUGH SATURDAY AS A CLIPPER SYSTEM PASSES NORTH OF
THE BORDER. TEMPERATURES WILL MODERATE TO ABOVE NORMAL LEVELS
TODAY AND SATURDAY...AND RETURN BACK TO NORMAL FOR SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1244 PM EST FRIDAY...ALL STEADY LIGHT SNOW HAS COME TO AN END
ACROSS THE REGION WITH THIS MORNINGS SNOW LEAVING BEHIND A HALF
INCH TO LOCALLY TWO INCHES OF ACCUMULATION. HOWEVER WITH LINGERING
MOISTURE AND A WARM FRONTAL BOUNDARY REMAINING DRAPED ACROSS THE
AREA THIS AFTERNOON...WIDESPREAD CLOUDS AND POCKETS OF LIGHT
PRECIPITATION REMAIN. SOME ISOLATED AREAS OF LIGHT PRECIPITATION
AND MIST WILL LIKELY CONTINUE ACROSS THE HIGHER ELEVATIONS BUT
AMOUNTS WILL BE VERY LIGHT. WITH WARMING LOW LEVELS AND SHALLOW
MOISTURE...THE PRECIPITATION WILL FALL IN THE FORM OF A LIGHT
DRIZZLE OR FREEZING DRIZZLE WITH A FLURRY OR TWO POSSIBLE. OVERALL
NOT A BIG DEAL BUT A VERY LIGHT GLAZE OF ICE POSSIBLE ON SOME SURFACES.
MOST OF THE REGION WILL REMAIN DRY. TEMPERATURES WILL RISE THROUGH
THE DAY WITH HIGHS LATE IN THE AFTERNOON CLIMBING INTO THE 30S IN
MOST LOCATIONS. SEEING A LOW LEVEL JET PASSING THROUGH THE REGION
CURRENTLY...SO SOME 20 KNOT GUSTS WILL BE SEEN THIS AFTERNOON...ESPECIALLY
IN THE CHAMPLAIN VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
AS OF 406 AM EST FRIDAY...CHANCES FOR SOME INTERMITTENT LIGHT
SNOW SHOWERS WILL CONTINUE TONIGHT AS THE SURFACE LOW TRACKS
NORTH OF THE BORDER...THOUGH WILL BE MAINLY CONFINED AGAIN TO THE
NORTHERN ZONES. THE REGION REMAINS UNDER CLOUDY SKIES AND
SOUTH/SOUTHWEST FLOW SO EXPECT OVERNIGHT TEMPS TO BE QUITE
MILD...MAINLY IN THE MID TO UPPER 20S. ATTENDING COLD FRONT WILL
PUSH THROUGH THE REGION SATURDAY AFTERNOON AND EVENING...WITH
CONTINUE CHANCES FOR LIGHT PRECIPITATION. PTYPE FOR SATURDAY WILL
BE MAINLY RAIN WITH SOME SNOW TO START THE DAY AS TEMPS AGAIN WILL
BE WELL ABOVE NORMAL WITH MOST LOCATIONS WARMING INTO THE UPPER
30S TO LOWER 40S. IN ADDITION...SOUTHWEST FLOW AHEAD OF THE FRONT
WILL PROVIDE THE POTENTIAL FOR SOME LAKE ENHANCED PRECIP DOWNWIND
OF LAKE ONTARIO...THOUGH PROBABLY WON`T BE LONG LIVED AS HIGH
PRESSURE WILL BEGIN TO BUILD INTO THE REGION LATE SATURDAY NIGHT
INTO SUNDAY. DRY CONDITIONS AND MORE SEASONABLE TEMPERATURES ARE
EXPECTED FOR SUNDAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 445 AM EST FRIDAY...A RIDGE OF HIGH PRESSURE WILL BUILD
INTO THE REGION SUNDAY NIGHT AND MONDAY WITH FAIR AND DRY WEATHER
EXPECTED. ECMWF AND GFS MODELS SHOW WARM AIR ADVECTION DEVELOPING
ALOFT LATE MONDAY NIGHT AND TUESDAY...AS ANOTHER WARM FRONT
APPROACHES THE REGION. HAVE GONE WITH SLIGHT CHANCE POPS FOR SNOW
SHOWERS FROM LATE MONDAY NIGHT THROUGH TUESDAY NIGHT. ECMWF AND
GFS MODELS SHOW A RIDGE OF HIGH PRESSURE AT THE SURFACE AND ALOFT
WILL BUILD OVER THE REGION ON WEDNESDAY...WITH FAIR AND DRY
WEATHER EXPECTED.
ECMWF AND GFS MODELS SHOW A CLOSED UPPER LOW OVER THE CAROLINAS
EARLY WEDNESDAY NIGHT...WITH A DIGGING UPPER TROUGH OVER THE UPPER
MIDWEST. ECMWF AND GFS MODELS SHOW MOISTURE FROM THE LOW OVER THE
SOUTHEASTERN U.S. WILL MOVE INTO THE NORTH COUNTRY AFTER MIDNIGHT
WEDNESDAY NIGHT. LOOKS LIKE THE REGION WILL SEE SOME MIXED
PRECIPITATION DEVELOP LATE WEDNESDAY NIGHT AND CONTINUE INTO EARLY
THURSDAY MORNING...AS SURFACE TEMPERATURES WILL BE BELOW
FREEZING...BUT TEMPERATURES AT 850 MB WILL BE CLIMBING ABOVE ZERO
DEGREES CELSIUS. ECMWF AND GFS MODELS DIFFER WITH THE HANDLING OF
THE UPPER TROUGH IN THE NORTHERN STREAM OVER THE UPPER
MIDWEST...WITH THE GFS FASTER AND MORE PROGRESSIVE THEN THE ECMWF.
THE GFS MODEL WOULD KEEP A BIT COOLER ALOFT AT 850 MB THEN THE
ECMWF...AND WOULD IMPLY A CHANGE TO SNOW LATER IN THE DAY ON
THURSDAY ACROSS THE REGION. THE ECMWF IS WARMER THEN THE GFS MODEL
AT 850 MB ON THURSDAY AND WOULD IMPLY A MAINLY RAIN EVENT DURING
THE DAY ON THURSDAY. GIVEN MODEL DIFFERENCES...HAVE WORDED THE
FORECAST RAIN OR SNOW LIKELY ON THURSDAY. HOWEVER...THAT
SAID...WILL FAVOR THE WARMER ECMWF SOLUTION FOR THURSDAY...WHICH
WOULD MEAN A MAINLY RAIN EVENT ACROSS THE REGION ON THURSDAY. FEEL
THE ECMWF HAS THE RIGHT IDEA WITH THIS...GIVEN THE FACT THAT BOTH
THE GFS AND ECMWF MODELS DO NOT HAVE A COLD HIGH PRESSURE AREA
OVER QUEBEC ON THURSDAY WHICH WOULD KEEP COLDER AIR IN PLACE OVER
THE REGION. ESPECIALLY GIVEN THE MILD FALL AND EARLY WINTER WE
HAVE HAD SO FAR ACROSS THE REGION.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...A SURFACE WARM FRNT CONTS TO PRODUCE PLENTY
OF CLOUDS ACRS OUR TAF SITES THIS AFTN...WITH RADAR SHOWING JUST A
FEW FLURRIES. VIS SATL PIC SHOWS CLRING SKIES ACRS CENTRAL
NY...TRYING TO MOVE TWD OUR REGION THIS AFTN. TAF CHALLENGE WL BE
AMOUNT OF LLVL MOISTURE AND POTENTIAL FOR MVFR/IFR CONDITIONS
TONIGHT. RUC AND NAM SOUNDINGS SHOW PLENTY OF LLVL MOISTURE
DEVELOPING AFT 00Z THIS EVENING AS WARM AIR MOVES ACRS THE
RELATIVELY COLD/SNOW COVERED GROUND. IN ADDITION...SOME MELTING WL
ALSO ADD TO THE MOISTURE IN THE BL. WL MENTION MVFR CIGS AT MOST
TAF SITES...WITH BEST POTENTIAL FOR IFR AT MPV/SLK/MSS. AT MSS NE
SFC WINDS WL SHIFT TO THE SW BY 03Z THIS EVENING...AS SFC WARM
FRNT FINALLY LIFTS THRU THE SLV. ALSO...PATCHY AREAS OF
DRIZZLE/FREEZING DRIZZLE WL BE POSSIBLE...GIVEN AMOUNT OF LLVL
MOISTURE PROGGED TO BE ACRS OUR MTN SITES...BUT NO ICE
ACCUMULATION IS ANTICIPATING. IMPROVING CONDITIONS WL DEVELOP BY
14Z SATURDAY...WITH SOUTHERLY FLW OF 5 TO 15 KNTS.
OUTLOOK 18Z SATURDAY THROUGH TUESDAY...
ON SATURDAY EVENING A SURFACE COLD FRNT WL PRODUCE SCATTERED RAIN
AND SNOW SHOWERS...WHICH WL CHANGE TO ALL SNOW BY LATE EVENING.
OCCASIONAL IFR CONDITIONS FOR SEVERAL HRS WL BE POSSIBLE ON SAT
NIGHT INTO SUNDAY...ESPECIALLY AT MPV/SLK. OTHERWISE...SFC HIGH PRES
AND VFR CONDITIONS WL PREVAIL SUNDAY AFTN THRU TUESDAY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...MUCCILLI
SHORT TERM...LAHIFF
LONG TERM...WGH
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1244 PM EST FRI JAN 6 2012
.SYNOPSIS...
A WARM FRONT PUSHING THROUGH THE NORTHEAST WILL CONTINUE TO
PROVIDE SOME LIGHT SNOW TO THE NORTH COUNTRY TODAY. MAINLY DRY
WEATHER IS EXPECTED FOR THE WEEKEND...THOUGH SOME PERIODS OF
LIGHT PRECIPITATION ARE POSSIBLE ACROSS NORTHERN PORTIONS OF THE
AREA TONIGHT THROUGH SATURDAY AS A CLIPPER SYSTEM PASSES NORTH OF
THE BORDER. TEMPERATURES WILL MODERATE TO ABOVE NORMAL LEVELS
TODAY AND SATURDAY...AND RETURN BACK TO NORMAL FOR SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 921 AM EST FRIDAY...ALL STEADY LIGHT SNOW HAS COME TO AN END
ACROSS THE REGION WITH THIS MORNINGS SNOW LEAVING BEHIND A HALF
INCH TO LOCALLY TWO INCHES OF ACCUMULATION. HOWEVER WITH LINGERING
MOISTURE AND A WARM FRONTAL BOUNDARY REMAINING DRAPED ACROSS THE
AREA THIS AFTERNOON...WIDESPREAD CLOUDS AND POCKETS OF LIGHT
PRECIPITATION REMAIN. SOME ISOLATED AREAS OF LIGHT PRECIPITATION
AND MIST WILL LIKELY CONTINUE ACROSS THE HIGHER ELEVATIONS BUT
AMOUNTS WILL BE VERY LIGHT. WITH WARMING LOW LEVELS AND SHALLOW
MOISTURE...THE PRECIPITATION WILL FALL IN THE FORM OF A LIGHT
DRIZZLE OR FREEZING DRIZZLE WITH A FLURRY OR TWO POSSIBLE. OVERALL
NOT A BIG DEAL BUT A VERY LIGHT GLAZE OF ICE POSSIBLE ON SOME SURFACES.
MOST OF THE REGION WILL REMAIN DRY. TEMPERATURES WILL RISE THROUGH
THE DAY WITH HIGHS LATE IN THE AFTERNOON CLIMBING INTO THE 30S IN
MOST LOCATIONS. SEEING A LOW LEVEL JET PASSING THROUGH THE REGION
CURRENTLY...SO SOME 20 KNOT GUSTS WILL BE SEEN THIS AFTERNOON...ESPECIALLY
IN THE CHAMPLAIN VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
AS OF 406 AM EST FRIDAY...CHANCES FOR SOME INTERMITTENT LIGHT
SNOW SHOWERS WILL CONTINUE TONIGHT AS THE SURFACE LOW TRACKS
NORTH OF THE BORDER...THOUGH WILL BE MAINLY CONFINED AGAIN TO THE
NORTHERN ZONES. THE REGION REMAINS UNDER CLOUDY SKIES AND
SOUTH/SOUTHWEST FLOW SO EXPECT OVERNIGHT TEMPS TO BE QUITE
MILD...MAINLY IN THE MID TO UPPER 20S. ATTENDING COLD FRONT WILL
PUSH THROUGH THE REGION SATURDAY AFTERNOON AND EVENING...WITH
CONTINUE CHANCES FOR LIGHT PRECIPITATION. PTYPE FOR SATURDAY WILL
BE MAINLY RAIN WITH SOME SNOW TO START THE DAY AS TEMPS AGAIN WILL
BE WELL ABOVE NORMAL WITH MOST LOCATIONS WARMING INTO THE UPPER
30S TO LOWER 40S. IN ADDITION...SOUTHWEST FLOW AHEAD OF THE FRONT
WILL PROVIDE THE POTENTIAL FOR SOME LAKE ENHANCED PRECIP DOWNWIND
OF LAKE ONTARIO...THOUGH PROBABLY WON`T BE LONG LIVED AS HIGH
PRESSURE WILL BEGIN TO BUILD INTO THE REGION LATE SATURDAY NIGHT
INTO SUNDAY. DRY CONDITIONS AND MORE SEASONABLE TEMPERATURES ARE
EXPECTED FOR SUNDAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 445 AM EST FRIDAY...A RIDGE OF HIGH PRESSURE WILL BUILD
INTO THE REGION SUNDAY NIGHT AND MONDAY WITH FAIR AND DRY WEATHER
EXPECTED. ECMWF AND GFS MODELS SHOW WARM AIR ADVECTION DEVELOPING
ALOFT LATE MONDAY NIGHT AND TUESDAY...AS ANOTHER WARM FRONT
APPROACHES THE REGION. HAVE GONE WITH SLIGHT CHANCE POPS FOR SNOW
SHOWERS FROM LATE MONDAY NIGHT THROUGH TUESDAY NIGHT. ECMWF AND
GFS MODELS SHOW A RIDGE OF HIGH PRESSURE AT THE SURFACE AND ALOFT
WILL BUILD OVER THE REGION ON WEDNESDAY...WITH FAIR AND DRY
WEATHER EXPECTED.
ECMWF AND GFS MODELS SHOW A CLOSED UPPER LOW OVER THE CAROLINAS
EARLY WEDNESDAY NIGHT...WITH A DIGGING UPPER TROUGH OVER THE UPPER
MIDWEST. ECMWF AND GFS MODELS SHOW MOISTURE FROM THE LOW OVER THE
SOUTHEASTERN U.S. WILL MOVE INTO THE NORTH COUNTRY AFTER MIDNIGHT
WEDNESDAY NIGHT. LOOKS LIKE THE REGION WILL SEE SOME MIXED
PRECIPITATION DEVELOP LATE WEDNESDAY NIGHT AND CONTINUE INTO EARLY
THURSDAY MORNING...AS SURFACE TEMPERATURES WILL BE BELOW
FREEZING...BUT TEMPERATURES AT 850 MB WILL BE CLIMBING ABOVE ZERO
DEGREES CELSIUS. ECMWF AND GFS MODELS DIFFER WITH THE HANDLING OF
THE UPPER TROUGH IN THE NORTHERN STREAM OVER THE UPPER
MIDWEST...WITH THE GFS FASTER AND MORE PROGRESSIVE THEN THE ECMWF.
THE GFS MODEL WOULD KEEP A BIT COOLER ALOFT AT 850 MB THEN THE
ECMWF...AND WOULD IMPLY A CHANGE TO SNOW LATER IN THE DAY ON
THURSDAY ACROSS THE REGION. THE ECMWF IS WARMER THEN THE GFS MODEL
AT 850 MB ON THURSDAY AND WOULD IMPLY A MAINLY RAIN EVENT DURING
THE DAY ON THURSDAY. GIVEN MODEL DIFFERENCES...HAVE WORDED THE
FORECAST RAIN OR SNOW LIKELY ON THURSDAY. HOWEVER...THAT
SAID...WILL FAVOR THE WARMER ECMWF SOLUTION FOR THURSDAY...WHICH
WOULD MEAN A MAINLY RAIN EVENT ACROSS THE REGION ON THURSDAY. FEEL
THE ECMWF HAS THE RIGHT IDEA WITH THIS...GIVEN THE FACT THAT BOTH
THE GFS AND ECMWF MODELS DO NOT HAVE A COLD HIGH PRESSURE AREA
OVER QUEBEC ON THURSDAY WHICH WOULD KEEP COLDER AIR IN PLACE OVER
THE REGION. ESPECIALLY GIVEN THE MILD FALL AND EARLY WINTER WE
HAVE HAD SO FAR ACROSS THE REGION.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...A SURFACE WARM FRNT CONTS TO PRODUCE PLENTY
OF CLOUDS ACRS OUR TAF SITES THIS AFTN...WITH RADAR SHOWING JUST A
FEW FLURRIES. VIS SATL PIC SHOWS CLRING SKIES ACRS CENTRAL
NY...TRYING TO MOVE TWD OUR REGION THIS AFTN. TAF CHALLENGE WL BE
AMOUNT OF LLVL MOISTURE AND POTENTIAL FOR MVFR/IFR CONDITIONS
TONIGHT. RUC AND NAM SOUNDINGS SHOW PLENTY OF LLVL MOISTURE
DEVELOPING AFT 00Z THIS EVENING AS WARM AIR MOVES ACRS THE
RELATIVELY COLD/SNOW COVERED GROUND. IN ADDITION...SOME MELTING WL
ALSO ADD TO THE MOISTURE IN THE BL. WL MENTION MVFR CIGS AT MOST
TAF SITES...WITH BEST POTENTIAL FOR IFR AT MPV/SLK/MSS. AT MSS NE
SFC WINDS WL SHIFT TO THE SW BY 03Z THIS EVENING...AS SFC WARM
FRNT FINALLY LIFTS THRU THE SLV. ALSO...PATCHY AREAS OF
DRIZZLE/FREEZING DRIZZLE WL BE POSSIBLE...GIVEN AMOUNT OF LLVL
MOISTURE PROGGED TO BE ACRS OUR MTN SITES...BUT NO ICE
ACCUMULATION IS ANTICIPATING. IMPROVING CONDITIONS WL DEVELOP BY
14Z SATURDAY...WITH SOUTHERLY FLW OF 5 TO 15 KNTS.
OUTLOOK 18Z SATURDAY THROUGH TUESDAY...
ON SATURDAY EVENING A SURFACE COLD FRNT WL PRODUCE SCATTERED RAIN
AND SNOW SHOWERS...WHICH WL CHANGE TO ALL SNOW BY LATE EVENING.
OCCASIONAL IFR CONDITIONS FOR SEVERAL HRS WL BE POSSIBLE ON SAT
NIGHT INTO SUNDAY...ESPECIALLY AT MPV/SLK. OTHERWISE...SFC HIGH PRES
AND VFR CONDITIONS WL PREVAIL SUNDAY AFTN THRU TUESDAY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...MUCCILLI
SHORT TERM...LAHIFF
LONG TERM...WGH
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1234 PM EST FRI JAN 6 2012
.SYNOPSIS...
A WARM FRONT PUSHING THROUGH THE NORTHEAST WILL CONTINUE TO
PROVIDE SOME LIGHT SNOW TO THE NORTH COUNTRY TODAY. MAINLY DRY
WEATHER IS EXPECTED FOR THE WEEKEND...THOUGH SOME PERIODS OF
LIGHT PRECIPITATION ARE POSSIBLE ACROSS NORTHERN PORTIONS OF THE
AREA TONIGHT THROUGH SATURDAY AS A CLIPPER SYSTEM PASSES NORTH OF
THE BORDER. TEMPERATURES WILL MODERATE TO ABOVE NORMAL LEVELS
TODAY AND SATURDAY...AND RETURN BACK TO NORMAL FOR SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 921 AM EST FRIDAY...MAIN AREA OF LIGHT SNOW ASSOCIATED WITH
A WARM FRONT HAS PASSED THROUGH THE MAJORITY OF THE REGION WITH A
GENERAL ACCUMULATION FROM A HALF INCH TO 2 INCHES. LIGHT SNOW WILL
CONTINUE OVER THE NORTHEAST KINGDOM OVER THE NEXT COUPLE OF HOURS
WITH STEADY PRECIPITATION GENERALLY OVER BY NOON. HOWEVER WITH
LINGERING MOISTURE AND FRONTAL BOUNDARY REMAINING DRAPED ACROSS THE AREA
THROUGH THE REST OF THE DAY...CLOUDS AND AREAS OF LIGHT
PRECIPITATION ARE EXPECTED TO CONTINUE THROUGH THE AFTERNOON AND
EVENING ACROSS NORTHERN AREAS AND ESPECIALLY IN THE HIGHER
ELEVATIONS OF THE NORTHEAST KINGDOM. WITH WARMING LOW LEVELS AND
SHALLOW MOISTURE...MOST PRECIPITATION WILL LIKELY BE IN THE FORM
OF LIGHT DRIZZLE OR FREEZING DRIZZLE WITH A FEW FLURRIES STILL
POSSIBLE AS WELL. NOT A BIG DEAL...BUT A LIGHT GLAZE ON SOME
SURFACES IS POSSIBLE. CENTRAL AND SOUTHERN VERMONT SHOULD BE
MOSTLY DRY. TEMPERATURES WILL RISE THROUGH THE DAY WITH HIGHS LATE
IN THE AFTERNOON RANGING FROM NEAR 30 IN THE NORTHEAST KINGDOM TO
THE MID AND UPPER 30S IN THE CHAMPLAIN AND SAINT LAWRENCE VALLEYS.
A LOW LEVEL JET WILL ALSO PASS THROUGH THE REGION WITH THE FRONTAL
ZONE...SO SOME GUSTS TO 20 KNOTS POSSIBLE IN THE LATE MORNING AND
EARLY AFTERNOON HOURS...ESPECIALLY IN THE CHAMPLAIN VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
AS OF 406 AM EST FRIDAY...CHANCES FOR SOME INTERMITTENT LIGHT
SNOW SHOWERS WILL CONTINUE TONIGHT AS THE SURFACE LOW TRACKS
NORTH OF THE BORDER...THOUGH WILL BE MAINLY CONFINED AGAIN TO THE
NORTHERN ZONES. THE REGION REMAINS UNDER CLOUDY SKIES AND
SOUTH/SOUTHWEST FLOW SO EXPECT OVERNIGHT TEMPS TO BE QUITE
MILD...MAINLY IN THE MID TO UPPER 20S. ATTENDING COLD FRONT WILL
PUSH THROUGH THE REGION SATURDAY AFTERNOON AND EVENING...WITH
CONTINUE CHANCES FOR LIGHT PRECIPITATION. PTYPE FOR SATURDAY WILL
BE MAINLY RAIN WITH SOME SNOW TO START THE DAY AS TEMPS AGAIN WILL
BE WELL ABOVE NORMAL WITH MOST LOCATIONS WARMING INTO THE UPPER
30S TO LOWER 40S. IN ADDITION...SOUTHWEST FLOW AHEAD OF THE FRONT
WILL PROVIDE THE POTENTIAL FOR SOME LAKE ENHANCED PRECIP DOWNWIND
OF LAKE ONTARIO...THOUGH PROBABLY WON`T BE LONG LIVED AS HIGH
PRESSURE WILL BEGIN TO BUILD INTO THE REGION LATE SATURDAY NIGHT
INTO SUNDAY. DRY CONDITIONS AND MORE SEASONABLE TEMPERATURES ARE
EXPECTED FOR SUNDAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 445 AM EST FRIDAY...A RIDGE OF HIGH PRESSURE WILL BUILD
INTO THE REGION SUNDAY NIGHT AND MONDAY WITH FAIR AND DRY WEATHER
EXPECTED. ECMWF AND GFS MODELS SHOW WARM AIR ADVECTION DEVELOPING
ALOFT LATE MONDAY NIGHT AND TUESDAY...AS ANOTHER WARM FRONT
APPROACHES THE REGION. HAVE GONE WITH SLIGHT CHANCE POPS FOR SNOW
SHOWERS FROM LATE MONDAY NIGHT THROUGH TUESDAY NIGHT. ECMWF AND
GFS MODELS SHOW A RIDGE OF HIGH PRESSURE AT THE SURFACE AND ALOFT
WILL BUILD OVER THE REGION ON WEDNESDAY...WITH FAIR AND DRY
WEATHER EXPECTED.
ECMWF AND GFS MODELS SHOW A CLOSED UPPER LOW OVER THE CAROLINAS
EARLY WEDNESDAY NIGHT...WITH A DIGGING UPPER TROUGH OVER THE UPPER
MIDWEST. ECMWF AND GFS MODELS SHOW MOISTURE FROM THE LOW OVER THE
SOUTHEASTERN U.S. WILL MOVE INTO THE NORTH COUNTRY AFTER MIDNIGHT
WEDNESDAY NIGHT. LOOKS LIKE THE REGION WILL SEE SOME MIXED
PRECIPITATION DEVELOP LATE WEDNESDAY NIGHT AND CONTINUE INTO EARLY
THURSDAY MORNING...AS SURFACE TEMPERATURES WILL BE BELOW
FREEZING...BUT TEMPERATURES AT 850 MB WILL BE CLIMBING ABOVE ZERO
DEGREES CELSIUS. ECMWF AND GFS MODELS DIFFER WITH THE HANDLING OF
THE UPPER TROUGH IN THE NORTHERN STREAM OVER THE UPPER
MIDWEST...WITH THE GFS FASTER AND MORE PROGRESSIVE THEN THE ECMWF.
THE GFS MODEL WOULD KEEP A BIT COOLER ALOFT AT 850 MB THEN THE
ECMWF...AND WOULD IMPLY A CHANGE TO SNOW LATER IN THE DAY ON
THURSDAY ACROSS THE REGION. THE ECMWF IS WARMER THEN THE GFS MODEL
AT 850 MB ON THURSDAY AND WOULD IMPLY A MAINLY RAIN EVENT DURING
THE DAY ON THURSDAY. GIVEN MODEL DIFFERENCES...HAVE WORDED THE
FORECAST RAIN OR SNOW LIKELY ON THURSDAY. HOWEVER...THAT
SAID...WILL FAVOR THE WARMER ECMWF SOLUTION FOR THURSDAY...WHICH
WOULD MEAN A MAINLY RAIN EVENT ACROSS THE REGION ON THURSDAY. FEEL
THE ECMWF HAS THE RIGHT IDEA WITH THIS...GIVEN THE FACT THAT BOTH
THE GFS AND ECMWF MODELS DO NOT HAVE A COLD HIGH PRESSURE AREA
OVER QUEBEC ON THURSDAY WHICH WOULD KEEP COLDER AIR IN PLACE OVER
THE REGION. ESPECIALLY GIVEN THE MILD FALL AND EARLY WINTER WE
HAVE HAD SO FAR ACROSS THE REGION.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...A SURFACE WARM FRNT CONTS TO PRODUCE PLENTY
OF CLOUDS ACRS OUR TAF SITES THIS AFTN...WITH RADAR SHOWING JUST A
FEW FLURRIES. VIS SATL PIC SHOWS CLRING SKIES ACRS CENTRAL
NY...TRYING TO MOVE TWD OUR REGION THIS AFTN. TAF CHALLENGE WL BE
AMOUNT OF LLVL MOISTURE AND POTENTIAL FOR MVFR/IFR CONDITIONS
TONIGHT. RUC AND NAM SOUNDINGS SHOW PLENTY OF LLVL MOISTURE
DEVELOPING AFT 00Z THIS EVENING AS WARM AIR MOVES ACRS THE
RELATIVELY COLD/SNOW COVERED GROUND. IN ADDITION...SOME MELTING WL
ALSO ADD TO THE MOISTURE IN THE BL. WL MENTION MVFR CIGS AT MOST
TAF SITES...WITH BEST POTENTIAL FOR IFR AT MPV/SLK/MSS. AT MSS NE
SFC WINDS WL SHIFT TO THE SW BY 03Z THIS EVENING...AS SFC WARM
FRNT FINALLY LIFTS THRU THE SLV. ALSO...PATCHY AREAS OF
DRIZZLE/FREEZING DRIZZLE WL BE POSSIBLE...GIVEN AMOUNT OF LLVL
MOISTURE PROGGED TO BE ACRS OUR MTN SITES...BUT NO ICE
ACCUMULATION IS ANTICIPATING. IMPROVING CONDITIONS WL DEVELOP BY
14Z SATURDAY...WITH SOUTHERLY FLW OF 5 TO 15 KNTS.
OUTLOOK 18Z SATURDAY THROUGH TUESDAY...
ON SATURDAY EVENING A SURFACE COLD FRNT WL PRODUCE SCATTERED RAIN
AND SNOW SHOWERS...WHICH WL CHANGE TO ALL SNOW BY LATE EVENING.
OCCASIONAL IFR CONDITIONS FOR SEVERAL HRS WL BE POSSIBLE ON SAT
NIGHT INTO SUNDAY...ESPECIALLY AT MPV/SLK. OTHERWISE...SFC HIGH PRES
AND VFR CONDITIONS WL PREVAIL SUNDAY AFTN THRU TUESDAY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...MUCCILLI
SHORT TERM...LAHIFF
LONG TERM...WGH
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
143 AM EST FRI JAN 6 2012
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE NORTH COUNTRY FOR A BRIEF TIME
TONIGHT. BY LATER TONIGHT...A WARM FRONT APPROACHING FROM THE
SOUTHWEST WILL BRING SOME LIGHT SNOW TO THE REGION. SOME PERIODS OF
LIGHT PRECIPITATION CAN BE EXPECTED FRIDAY THROUGH SATURDAY AS A
CLIPPER SYSTEM PASSES NORTH OF THE BORDER. TEMPERATURES WILL
MODERATE TO ABOVE NORMAL LEVELS FRIDAY AND SATURDAY...AND RETURN
BACK TO NORMAL FOR SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1232 AM EST FRIDAY...AREA OF LIGHT SNOW SHOWERS DRIVEN BY
WARM AIR ADVECTION IS BREAKING OUT ACROSS THE SAINT LAWRENCE
VALLEY AND INTO THE NORTHERN ADIRONDACKS AT THIS TIME WITH REDUCED
VISIBILITIES DOWN TO 1 MILE BEGIN REPORTED AT SEVERAL AUTOMATED
WEATHER STATIONS. LATEST 3KM RUC HAS A VERY GOOD HANDLE ON THE
CURRENT CONDITIONS...AND SHOWS LIGHT SNOW SPREADING ACROSS THE
FORECAST AREA THROUGH THE EARLY MORNING HOURS...THEN SHIFTING
NORTHWARD AFTER 12Z AS THE ASSOCIATED WARM FRONT DOES THE SAME.
THUS...HAVE INCREASED POPS TO LIKELY ACROSS MOST OF THE REGION FOR
THE REMAINDER OF THE OVERNIGHT HOURS TO ACCOUNT FOR THIS. UPSTREAM
OBS SHOW ANYWHERE FROM A TRACE TO 0.01" OF MELTED PRECIP PER HOUR
FROM SNOW...SO THINKING OVER THE NEXT 6-8 HOURS WE`LL LIKELY SEE
ABOUT 1/2 A TENTH OF AN INCH OF LIQUID...ACCUMULATING TO ABOUT
1-2" ACROSS CENTRAL AND NORTHERN PORTIONS OF THE REGION...A
DUSTING TO AN INCH SOUTH. OVERNIGHT MIN TEMPS ALREADY
OCCURRED...AND THE PREVIOUS FORECAST OF RISING TEMPS OVERNIGHT
STILL LOOKS GOOD.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY NIGHT/...
AS OF 341 PM EST THURSDAY...LOW PRESSURE WILL TRACK EASTWARD ACROSS
SOUTHERN ONTARIO AND QUEBEC FRIDAY THROUGH SATURDAY. SOME LIGHT
SNOW EXPECTED ACROSS MUCH OF THE AREA FRIDAY MORNING...ESPECIALLY
NORTHERN AREAS...AS THE WARM FRONT ASSOCIATED WITH THIS LOW LIFTS
NORTH ACROSS THE AREA. ANY SNOW ACCUMULATIONS FRIDAY MORNING WILL
BE ON THE LIGHT SIDE...WITH A DUSTING TO AN INCH OR TWO
EXPECTED...MAINLY ACROSS THE NORTHERN ZONES. PRECIPITATION WILL
BE SPOTTY IN NATURE DURING THE AFTERNOON WITH SOME LIGHT SNOW
SHOWERS POSSIBLE. AREA OF FAVORABLE SNOW GROWTH FRIDAY AFTERNOON
DOESN`T COINCIDE WITH MOISTURE...SO THERE MAY BE SOME FREEZING
DRIZZLE OR DRIZZLE AS WELL. MAX TEMPS WILL RANGE FROM THE UPPER
20S IN THE NORTHEAST KINGDOM TO THE MID 30S SOUTHERN ZONES.
CHANCES FOR SOME INTERMITTENT LIGHT SNOW/RAIN SHOWERS WILL CONTINUE
FRIDAY NIGHT THROUGH SATURDAY AS THE SURFACE LOW TRACKS NORTH OF THE
BORDER. CHANCE OF SNOW SHOWERS SATURDAY NIGHT AS COLD FRONT MOVES
SOUTHEAST ACROSS THE AREA. TEMPERATURES FRIDAY NIGHT/SATURDAY WELL
ABOVE SEASONAL NORMS. EXPECT HIGHS ON SATURDAY TO BE IN THE UPPER
30S AND LOWER 40S.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 300 PM EST THURSDAY...VERY QUIET WX WL PREVAIL THRU THE
MIDDLE OF NEXT WK...FOLLOWED BY MUCH MORE ACTIVE PATTERN FOR NEXT THURS
INTO NEXT WKND. LARGE SCALE INDICES SHOW THE AO (ARCTIC OSCILLATION) BECMG
NEGATIVE TWD THE MID OF JAN...ALONG WITH A NEAR NEUTRAL NAO (NORTH
ATLANTIC OSCILLATION) ...SUGGESTING A POTENTIAL PATTERN CHANGE IS
COMING. THIS WOULD SUGGEST THE DEVELOPMENT OF ABOVE NORMAL HGHTS
ACRS GREENLAND...WITH POTENTIAL BLW NORMAL HGHTS OVER THE EASTERN
CONUS. AS THIS LARGE SCALE PATTERN CHANGE DEVELOPS...AN ACTIVE WX
PATTERN IS POSSIBLE ACRS THE EASTERN CONUS...INCLUDING OUR FA.
LATEST 12Z GFS ENSEMBLES...ECWMF...AND GFS ALL SHOW THE
DEVELOPMENT OF A SIGNIFICANT MID/UPPER LVL TROF ACRS THE CENTRAL
PLAINS ON WEDS OF NEXT WK...WHILE POTENT CLOSED 7H/5H CIRCULATION
EJECTS FROM THE SOUTHWEST CONUS IN THE SOUTHERN STREAM. STILL SOME
TIMING ISSUES WITH SYSTEM EJECTING FROM THE SW CONUS...BUT THESE
SYSTEMS TEND TO BE STRONGER THAN PROGGED BY MODELS AND ALMOST
NEVER WEAKEN AS QUICKLY AS MODELS PREDICT. THIS SYSTEM WL HAVE
PLENTY OF SUB- TROPICAL MOISTURE FROM THE GULF/ATLANTIC AS IT
MOVES TWD OUR REGION. HOWEVER...FEEL INTERACTION WITH NORTHERN
STREAM TROF WL BE LIMITED...THEREFORE EXPECTING A MAINLY WARM CORE
SYSTEM FOR THURSDAY. THIS SETUP LOOKS VERY SIMILAR TO OUR SYSTEM A
COUPLE WEEKS AGO...WHEN A POTENT MID/UPPER LVL CIRCULATION ACRS
THE NORTHERN GREAT LAKES...CAPTURED SOUTHERN STREAM LOW PRES AND
TRACKED IT TO OUR WEST...PLACING OUR CWA IN THE WARM SECTOR.
LATEST TRENDS HAVE BEEN SUPPRESSED FURTHER SOUTH WITH LOW PRES
TRACK AS COOL HIGH PRES DEVELOPS TO OUR NORTH...OFFERING A
POTENTIAL FOR A COLDER/SNOWIER SOLUTION...BUT NO BUYING THIS YET.
WL FCST SFC LOW PRES TRACKING TO OUR WEST...WHICH WL RESULT IN
SNOW CHANGING TO MIX...THEN TO RAIN...AND ENDING AS A PERIOD OF
SNOW...WITH SOME ACCUMULATION ACRS THE MTNS LIKELY. ALSO...GIVEN
THICKNESS FIELDS AND COLD GROUND TEMPS...WOULD ANTICIPATE SOME
MINOR ICE ACCUMULATION EAST OF THE GREENS. OTHERWISE...STILL
PLENTY OF UNCERTAINTY WITH SYSTEM 6 DAYS OUT...AND CHANGES WL BE
COMING...GIVEN COMPLEX MID/UPPER LVL PATTERN. OVERALL...TEMPS WL
AVERAGE NEAR NORMAL FOR SUNDAY THRU TUES...THEN INCREASE TO ABOVE
NORMAL LEVELS FOR WEDS INTO THURS...AS CLOUDS/PRECIP LIMIT THE
DIURNAL RANGE.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
THROUGH 06Z SATURDAY...A WARM FRONT APPROACHING THE REGION THIS
MORNING WILL BRING LIGHT SNOW TO THE REGION TODAY...WITH CONDITIONS
LOWERING TO IFR IN SNOW. EXPECTING LIGHT SNOW TO BEGIN TO TAPER
OFF ACROSS THE REGION BY 18Z FRIDAY...AS THE WARM FRONT BEGINS TO
LIFT NORTH OF THE REGION. EXPECTING VFR CONDITIONS ACROSS THE REGION
AFTER 00Z SATURDAY.
OUTLOOK 06Z SATURDAY THROUGH TUESDAY...THE COMBINATION OF WEAK
LOW PRESSSURE AND ANOTHER SURFACE COLD FRONT WILL PRODUCE MORE
SCATTERED SNOW SHOWERS ON SATURDAY...ALONG WITH SOME IFR/MVFR
CONDITIONS...ESPECIALLY AT SLK/MPV. OTHERWISE...HIGH PRES WITH VFR
CONDITIONS WILL PREVAIL SUNDAY INTO MONDAY. ANOTHER WARM FRONT APPROACHING
THE REGION ON TUESDAY WILL BRING ANOTHER CHANCE FOR SNOW SHOWERS
ON TUESDAY WITH SOME MVFR/IFR CONDITIONS POSSIBLE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...RJS/LOCONTO
NEAR TERM...LAHIFF
SHORT TERM...RJS
LONG TERM...TABER
AVIATION...WGH/TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1233 AM EST FRI JAN 6 2012
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE NORTH COUNTRY FOR A BRIEF TIME
TONIGHT. BY LATER TONIGHT...A WARM FRONT APPROACHING FROM THE
SOUTHWEST WILL BRING SOME LIGHT SNOW TO THE REGION. SOME PERIODS OF
LIGHT PRECIPITATION CAN BE EXPECTED FRIDAY THROUGH SATURDAY AS A
CLIPPER SYSTEM PASSES NORTH OF THE BORDER. TEMPERATURES WILL
MODERATE TO ABOVE NORMAL LEVELS FRIDAY AND SATURDAY...AND RETURN
BACK TO NORMAL FOR SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1232 AM EST FRIDAY...AREA OF LIGHT SNOW SHOWERS DRIVEN BY
WARM AIR ADVECTION IS BREAKING OUT ACROSS THE SAINT LAWRENCE
VALLEY AND INTO THE NORTHERN ADIRONDACKS AT THIS TIME WITH REDUCED
VISIBILITIES DOWN TO 1 MILE BEGIN REPORTED AT SEVERAL AUTOMATED
WEATHER STATIONS. LATEST 3KM RUC HAS A VERY GOOD HANDLE ON THE
CURRENT CONDITIONS...AND SHOWS LIGHT SNOW SPREADING ACROSS THE
FORECAST AREA THROUGH THE EARLY MORNING HOURS...THEN SHIFTING
NORTHWARD AFTER 12Z AS THE ASSOCIATED WARM FRONT DOES THE SAME.
THUS...HAVE INCREASED POPS TO LIKELY ACROSS MOST OF THE REGION FOR
THE REMAINDER OF THE OVERNIGHT HOURS TO ACCOUNT FOR THIS. UPSTREAM
OBS SHOW ANYWHERE FROM A TRACE TO 0.01" OF MELTED PRECIP PER HOUR
FROM SNOW...SO THINKING OVER THE NEXT 6-8 HOURS WE`LL LIKELY SEE
ABOUT 1/2 A TENTH OF AN INCH OF LIQUID...ACCUMULATING TO ABOUT
1-2" ACROSS CENTRAL AND NORTHERN PORTIONS OF THE REGION...A
DUSTING TO AN INCH SOUTH. OVERNIGHT MIN TEMPS ALREADY
OCCURRED...AND THE PREVIOUS FORECAST OF RISING TEMPS OVERNIGHT
STILL LOOKS GOOD.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY NIGHT/...
AS OF 341 PM EST THURSDAY...LOW PRESSURE WILL TRACK EASTWARD ACROSS
SOUTHERN ONTARIO AND QUEBEC FRIDAY THROUGH SATURDAY. SOME LIGHT
SNOW EXPECTED ACROSS MUCH OF THE AREA FRIDAY MORNING...ESPECIALLY
NORTHERN AREAS...AS THE WARM FRONT ASSOCIATED WITH THIS LOW LIFTS
NORTH ACROSS THE AREA. ANY SNOW ACCUMULATIONS FRIDAY MORNING WILL
BE ON THE LIGHT SIDE...WITH A DUSTING TO AN INCH OR TWO
EXPECTED...MAINLY ACROSS THE NORTHERN ZONES. PRECIPITATION WILL
BE SPOTTY IN NATURE DURING THE AFTERNOON WITH SOME LIGHT SNOW
SHOWERS POSSIBLE. AREA OF FAVORABLE SNOW GROWTH FRIDAY AFTERNOON
DOESN`T COINCIDE WITH MOISTURE...SO THERE MAY BE SOME FREEZING
DRIZZLE OR DRIZZLE AS WELL. MAX TEMPS WILL RANGE FROM THE UPPER
20S IN THE NORTHEAST KINGDOM TO THE MID 30S SOUTHERN ZONES.
CHANCES FOR SOME INTERMITTENT LIGHT SNOW/RAIN SHOWERS WILL CONTINUE
FRIDAY NIGHT THROUGH SATURDAY AS THE SURFACE LOW TRACKS NORTH OF THE
BORDER. CHANCE OF SNOW SHOWERS SATURDAY NIGHT AS COLD FRONT MOVES
SOUTHEAST ACROSS THE AREA. TEMPERATURES FRIDAY NIGHT/SATURDAY WELL
ABOVE SEASONAL NORMS. EXPECT HIGHS ON SATURDAY TO BE IN THE UPPER
30S AND LOWER 40S.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 300 PM EST THURSDAY...VERY QUIET WX WL PREVAIL THRU THE
MIDDLE OF NEXT WK...FOLLOWED BY MUCH MORE ACTIVE PATTERN FOR NEXT THURS
INTO NEXT WKND. LARGE SCALE INDICES SHOW THE AO (ARCTIC OSCILLATION) BECMG
NEGATIVE TWD THE MID OF JAN...ALONG WITH A NEAR NEUTRAL NAO (NORTH
ATLANTIC OSCILLATION) ...SUGGESTING A POTENTIAL PATTERN CHANGE IS
COMING. THIS WOULD SUGGEST THE DEVELOPMENT OF ABOVE NORMAL HGHTS
ACRS GREENLAND...WITH POTENTIAL BLW NORMAL HGHTS OVER THE EASTERN
CONUS. AS THIS LARGE SCALE PATTERN CHANGE DEVELOPS...AN ACTIVE WX
PATTERN IS POSSIBLE ACRS THE EASTERN CONUS...INCLUDING OUR FA.
LATEST 12Z GFS ENSEMBLES...ECWMF...AND GFS ALL SHOW THE
DEVELOPMENT OF A SIGNIFICANT MID/UPPER LVL TROF ACRS THE CENTRAL
PLAINS ON WEDS OF NEXT WK...WHILE POTENT CLOSED 7H/5H CIRCULATION
EJECTS FROM THE SOUTHWEST CONUS IN THE SOUTHERN STREAM. STILL SOME
TIMING ISSUES WITH SYSTEM EJECTING FROM THE SW CONUS...BUT THESE
SYSTEMS TEND TO BE STRONGER THAN PROGGED BY MODELS AND ALMOST
NEVER WEAKEN AS QUICKLY AS MODELS PREDICT. THIS SYSTEM WL HAVE
PLENTY OF SUB- TROPICAL MOISTURE FROM THE GULF/ATLANTIC AS IT
MOVES TWD OUR REGION. HOWEVER...FEEL INTERACTION WITH NORTHERN
STREAM TROF WL BE LIMITED...THEREFORE EXPECTING A MAINLY WARM CORE
SYSTEM FOR THURSDAY. THIS SETUP LOOKS VERY SIMILAR TO OUR SYSTEM A
COUPLE WEEKS AGO...WHEN A POTENT MID/UPPER LVL CIRCULATION ACRS
THE NORTHERN GREAT LAKES...CAPTURED SOUTHERN STREAM LOW PRES AND
TRACKED IT TO OUR WEST...PLACING OUR CWA IN THE WARM SECTOR.
LATEST TRENDS HAVE BEEN SUPPRESSED FURTHER SOUTH WITH LOW PRES
TRACK AS COOL HIGH PRES DEVELOPS TO OUR NORTH...OFFERING A
POTENTIAL FOR A COLDER/SNOWIER SOLUTION...BUT NO BUYING THIS YET.
WL FCST SFC LOW PRES TRACKING TO OUR WEST...WHICH WL RESULT IN
SNOW CHANGING TO MIX...THEN TO RAIN...AND ENDING AS A PERIOD OF
SNOW...WITH SOME ACCUMULATION ACRS THE MTNS LIKELY. ALSO...GIVEN
THICKNESS FIELDS AND COLD GROUND TEMPS...WOULD ANTICIPATE SOME
MINOR ICE ACCUMULATION EAST OF THE GREENS. OTHERWISE...STILL
PLENTY OF UNCERTAINTY WITH SYSTEM 6 DAYS OUT...AND CHANGES WL BE
COMING...GIVEN COMPLEX MID/UPPER LVL PATTERN. OVERALL...TEMPS WL
AVERAGE NEAR NORMAL FOR SUNDAY THRU TUES...THEN INCREASE TO ABOVE
NORMAL LEVELS FOR WEDS INTO THURS...AS CLOUDS/PRECIP LIMIT THE
DIURNAL RANGE.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
THROUGH 00Z SATURDAY...VFR CEILINGS INITIALLY WILL GIVE WAY TO
MVFR CEILINGS AFTER 06Z AND REMAINING IN THE MVFR CATEGORY THROUGH
THE REMAINDER OF THE PERIOD AS A WARM FRONT LIFTS NORTHEAST INTO
THE REGION. CEILINGS WILL LOWER INTO THE 1000 TO 2000 FOOT RANGE.
LIGHT SNOW WILL ALSO MOVE INTO THE REGION BEGINNING AROUND 06Z AND
ENDING AROUND 15Z WITH VISIBILITIES LOWERING INTO THE MVFR AND IFR
CATEGORIES. WINDS WILL BECOME MORE SOUTHERLY WITH TIME LATER
TONIGHT AND FRIDAY...BUT SPEEDS WILL BE UNDER 15 KNOTS.
OUTLOOK 00Z SATURDAY THROUGH MONDAY...SNOW SHOWER ACTIVITY SHOULD BE
NORTH OF OUR TAF SITES BY 00Z SATURDAY...HOWEVER COOL/MOIST NORTHEAST FLW
AT MSS...COULD RESULT IN AREAS OF FREEZING DRIZZLE WITH SOME MINOR
ICING POSSIBLE. IN ADDITION...MVFR/IFR CONDITIONS WL PREVAIL AT
MSS FRIDAY AFTN. THE COMBINATION OF WEAK LOW PRES AND ANOTHER SFC
COLD FRNT WL PRODUCE MORE SCATTERED SNOW SHOWERS ON
SATURDAY...ALONG WITH SOME IFR/MVFR CONDITIONS...ESPECIALLY AT
SLK/MPV. OTHERWISE...HIGH PRES WITH VFR CONDITIONS WL PREVAIL
SUNDAY INTO MONDAY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...RJS/LOCONTO
NEAR TERM...LAHIFF
SHORT TERM...RJS
LONG TERM...TABER
AVIATION...EVENSON/TABER
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
217 PM MST FRI JAN 6 2012
.DISCUSSION...
VERY FLAT LONG WAVE RIDGE IS AT ABOUT 125W THIS MORNING WITH
LARGELY ZONAL FLOW FROM THE DATE LINE TO THE EAST COAST OF THE US.
SHORT WAVE TROFS WERE NEAR LAKE WG AND SOUTH WEST WARD AND
APPROACHING THE WEST COAST OF CANADA. LONG WAVE RIDGE WILL REBUILD
AS THE SHORT WAVE TROF MOVES EAST WARD...SPLITTING INTO TWO PARTS.
THE SOUTHERN PORTION HEADS FOR AZ/NM WHILE THE NORTHERN PORTION
MOVES ACROSS THE NORTHERN ROCKIES AND LARGELY SHEARS OUT.
THE 1000 TO 500 MB MEAN TEMPERATURE ANOMALY AT RAPID CITY THIS
MORNING IS ABOUT +3C WITH SLIGHTLY BELOW NORMAL TEMPS OVER NORTH
WEST MT. THE ONLY REALLY COLD AIR LIES OVER WESTERN AK.
THE NORTHERN SHORT WAVE TROF CROSSES OUR AREA SUNDAY AM WITH
LITTLE INFLUENCE ON OUR WEATHER.
BRISK WINDS HAVE KEPT TEMPERATURES DOWN TODAY...BUT WILL BE QUICK
TO DIE OFF THIS EVENING AS PRESSURES RISE TO THE EAST AND BEGIN TO
FALL A BIT TO THE WEST CUTTING BACK ON THE PRESSURE GRADIENT. TEMPERATURES
WILL BE QUICK TO FALL DURING THE EVENING HOURS...BUT INCREASING
MOISTURE EVIDENT ON THE WATER VAPOR LOOP AND A BIT OF WARM
ADVECTION AT 700 MB WILL LEAD TO SOME INCREASE IN HIGH AND MID
CLOUDINESS LATER TONIGHT LIKELY SLOWING TEMPERATURE FALLS EARLY AM.
BOTH NAM AND RUC FORECAST SOUNDINGS SHOW THIS INCREASE IN MOISTURE
AND CLOUDINESS.
DRYING IS SHOWN ON THE SOUNDINGS LATE SATURDAY EVENING IN SPITE OF
APPROACH OF THE SHORT WAVE TROF. SURFACE WINDS ARE EXPECTED TO
REMAIN QUITE LIGHT THROUGH THE PERIOD.
EXTENDED...UPPER LEVEL RIDGE CROSSES THE NORTHERN PLAINS EARLY NEXT
WEEK. TEMPERATURES WILL REMAIN ABOVE SEASONAL AVERAGES THROUGH
TUESDAY. STRONG UPPER TROF AND ASSOCIATED SURFACE COLD FRONT CROSSES
THE AREA TUESDAY BRINGING A CHANCE OF RAIN OR SNOW TUESDAY INTO
TUESDAY NIGHT. MODELS SEEM TO BE TRENDING EARLIER WITH THE
TIMING...SO WILL WATCH FOR POP ADJUSTMENTS. SYSTEM SHIFTS EAST
QUICKLY WITH AREA REMAINING UNDER FAST NORTHWEST FLOW THROUGH
MIDWEEK. BOTH GFS AND EC TRY TO BUILD WESTERN RIDGE BACK ACROSS THE
ROCKIES FOR THE END OF THE WEEK.
&&
.AVIATION...00Z TAFS
VFR CONDITIONS WILL CONTINUE THROUGH SATURDAY.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...BARBER
LONG TERM....CALDERON
AVIATION...CALDERON
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1146 AM CST FRI JAN 6 2012
.UPDATE...
UPDATED GOING FORECAST TO BUMP UP AFTERNOON HIGHS BY SEVERAL
DEGREES THROUGHOUT THE CWA. TEMPERATURES CONTINUE TO RISE RAPIDLY
AT ALL OBSERVING LOCATIONS DESPITE WEAK CAA. LOW ALBEDO/LACK OF
SNOW COVER IS COMBINING WITH SIGNIFICANT VERTICAL MIXING DUE TO
THE MODERATE WEST WIND TO ALLOW TEMPS TO CLIMB A DEGREE OR TWO
EVERY HOUR. SEVERAL SPOTS NOW EXPECTED TO REACH OR SLIGHTLY EXCEED
THEIR DAILY HIGH TEMP RECORDS.
AVIATION DISCUSSION UPDATED FOR 18Z TAF ISSUANCE BELOW
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH SUNDAY
THE FORECAST CHALLENGE IS TEMPERATURE.
CURRENTLY...LOW LEVEL CAA IS OCCURRING. 925HPA TEMPS HAVE FALLEN 5C
TO 10C DEGREES OVER THE PAST 6 HOURS. TEMPERATURES ARE STEADY OR
SLOWLY FALLING MAINLY THROUGH THE 30S AMID A PARTLY CLOUDY SKY.
0.5KM WIND SPEEDS /PER RUC MODEL/ ARE 25 TO 40 KNOTS EARLY THIS
MORNING.
LOW LEVEL TEMPERATURES ARE CONTINUING TO COOL TODAY DOWN TO A
RANGE OF GENERALLY 0C TO +3C...WHICH IS ROUGHLY A 10C TO 15C DROP
IN 925HPA TEMPERATURES IN 24 HOURS. DIFFERENT FROM PREVIOUS DAYS
WHEN 0.5KM WIND SPEEDS WERE BETWEEN 25 AND 40 KNOTS...WIND SPEEDS
THAT STRONG TODAY WILL BE MIXING DOWN TO THE SURFACE MUCH MORE
EFFICIENTLY WHILE LOW LEVEL CAA IS ONGOING. SUSTAINED WINDS OF 15
TO 25 MPH WITH HIGHER GUSTS IS EXPECTED. HEADING INTO SATURDAY AND
SUNDAY...-2C TO +4C AIR AT 925HPA IS PROGGED TO RESIDE OVER THE
CWA. SO...BASICALLY LOOKING AT SIMILAR TEMPERATURES OVER THE NEXT
THREE DAYS...RANGING FROM THE UPPER 30S THROUGH THE MID 40S.
THE DRY FORECAST UNDER NW FLOW ALOFT ALSO PERSISTS THROUGH
SUNDAY...EVEN THOUGH A FEW SUBTLE S/W TROFS APPEAR TO WORK ACROSS
THE REGION.
.LONG TERM...SUNDAY NIGHT THROUGH WEDNESDAY
THE MODELS ARE IN REASONABLE AGREEMENT DURING THE LONG TERM
PERIOD...WITH JUST SOME DIFFERENCES CONCERNING PRECIPITATION
CHANCES TUESDAY NIGHT. LOOKING AT ANOTHER DECENT WARM UP EARLY IN
THE PERIOD AS THE REGION WILL BE UNDER UPPER LEVEL NORTHWEST FLOW
AND ON THE WAA SIDE OF A SURFACE TROUGH. HIGH TEMPERATURES IN THE
40S LOOK TO BE COMMON BOTH MONDAY AND TUESDAY. THE SURFACE
TROUGH/FRONT PUSHES ACROSS THE AREA TUESDAY EVENING AS AN UPPER
LEVEL SHORTWAVE SLIDES FROM CENTRAL CANADA TO THE GREAT LAKES BY
THURSDAY MORNING. THE BEST ENERGY LOOKS TO AFFECT THE CWA TUESDAY
NIGHT INTO EARLY WEDNESDAY. MODEL TIME SECTIONS SHOW PRETTY GOOD
LIFT...BUT NOT MUCH IN THE WAY OF LOWER TO MID LEVEL MOISTURE.
THE GFS IS THE LEAST AGGRESSIVE MODEL WITH THE PRECIPITATION...WHILE
THE ECMWF INDICATES THE POTENTIAL FOR AN INCH OR SO OF
ACCUMULATION. TOO MANY DIFFERENCES RIGHT NOW...SO WILL JUST STICK
WITH THE ALLBLEND SLIGHT CHANCE POPS. HIGH PRESSURE QUICKLY MOVES
IN BEHIND THE EXITING SYSTEM...AND LOOKS TO BRING MUCH COOLER AIR
THAN WE HAVE SEEN RECENTLY BACK TO THE REGION. H85 TEMPS FALL INTO
THE -6 TO -19 DEGREE RANGE ON WEDNESDAY...AND REMAIN COLD INTO THE
DAY THURSDAY...WITH THE POSSIBILITY OF NEAR TO SLIGHTLY BELOW
NORMAL HIGH TEMPERATURES BOTH WEDNESDAY AND THURSDAY.
&&
.AVIATION...
18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
PREVAILING VFR CONDITIONS ARE EXPECTED FOR ALL TAF SITES THROUGH AT
LEAST 1Z. HOWEVER LOW CLOUDS ACROSS NORTHERN NORTH DAKOTA WILL
TRACK SOUTHEASTWARD TONIGHT. THESE LOW CLOUDS MAY PRODUCE MVFR
CIGS IN KABR/KATY DURING THE OVERNIGHT HOURS.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...CHURCH
SHORT TERM...DORN
LONG TERM...PARKIN
AVIATION...SD
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
606 AM CST FRI JAN 6 2012
.UPDATE...
SEE UPDATED AVIATION DISCUSSION BELOW.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH SUNDAY
THE FORECAST CHALLENGE IS TEMPERATURE.
CURRENTLY...LOW LEVEL CAA IS OCCURRING. 925HPA TEMPS HAVE FALLEN 5C
TO 10C DEGREES OVER THE PAST 6 HOURS. TEMPERATURES ARE STEADY OR
SLOWLY FALLING MAINLY THROUGH THE 30S AMID A PARTLY CLOUDY SKY.
0.5KM WIND SPEEDS /PER RUC MODEL/ ARE 25 TO 40 KNOTS EARLY THIS
MORNING.
LOW LEVEL TEMPERATURES ARE CONTINUING TO COOL TODAY DOWN TO A
RANGE OF GENERALLY 0C TO +3C...WHICH IS ROUGHLY A 10C TO 15C DROP
IN 925HPA TEMPERATURES IN 24 HOURS. DIFFERENT FROM PREVIOUS DAYS
WHEN 0.5KM WIND SPEEDS WERE BETWEEN 25 AND 40 KNOTS...WIND SPEEDS
THAT STRONG TODAY WILL BE MIXING DOWN TO THE SURFACE MUCH MORE
EFFICIENTLY WHILE LOW LEVEL CAA IS ONGOING. SUSTAINED WINDS OF 15
TO 25 MPH WITH HIGHER GUSTS IS EXPECTED. HEADING INTO SATURDAY AND
SUNDAY...-2C TO +4C AIR AT 925HPA IS PROGGED TO RESIDE OVER THE
CWA. SO...BASICALLY LOOKING AT SIMILAR TEMPERATURES OVER THE NEXT
THREE DAYS...RANGING FROM THE UPPER 30S THROUGH THE MID 40S.
THE DRY FORECAST UNDER NW FLOW ALOFT ALSO PERSISTS THROUGH
SUNDAY...EVEN THOUGH A FEW SUBTLE S/W TROFS APPEAR TO WORK ACROSS
THE REGION.
.LONG TERM...SUNDAY NIGHT THROUGH WEDNESDAY
THE MODELS ARE IN REASONABLE AGREEMENT DURING THE LONG TERM
PERIOD...WITH JUST SOME DIFFERENCES CONCERNING PRECIPITATION
CHANCES TUESDAY NIGHT. LOOKING AT ANOTHER DECENT WARM UP EARLY IN
THE PERIOD AS THE REGION WILL BE UNDER UPPER LEVEL NORTHWEST FLOW
AND ON THE WAA SIDE OF A SURFACE TROUGH. HIGH TEMPERATURES IN THE
40S LOOK TO BE COMMON BOTH MONDAY AND TUESDAY. THE SURFACE
TROUGH/FRONT PUSHES ACROSS THE AREA TUESDAY EVENING AS AN UPPER
LEVEL SHORTWAVE SLIDES FROM CENTRAL CANADA TO THE GREAT LAKES BY
THURSDAY MORNING. THE BEST ENERGY LOOKS TO AFFECT THE CWA TUESDAY
NIGHT INTO EARLY WEDNESDAY. MODEL TIME SECTIONS SHOW PRETTY GOOD
LIFT...BUT NOT MUCH IN THE WAY OF LOWER TO MID LEVEL MOISTURE.
THE GFS IS THE LEAST AGGRESSIVE MODEL WITH THE PRECIPITATION...WHILE
THE ECMWF INDICATES THE POTENTIAL FOR AN INCH OR SO OF
ACCUMULATION. TOO MANY DIFFERENCES RIGHT NOW...SO WILL JUST STICK
WITH THE ALLBLEND SLIGHT CHANCE POPS. HIGH PRESSURE QUICKLY MOVES
IN BEHIND THE EXITING SYSTEM...AND LOOKS TO BRING MUCH COOLER AIR
THAN WE HAVE SEEN RECENTLY BACK TO THE REGION. H85 TEMPS FALL INTO
THE -6 TO -19 DEGREE RANGE ON WEDNESDAY...AND REMAIN COLD INTO THE
DAY THURSDAY...WITH THE POSSIBILITY OF NEAR TO SLIGHTLY BELOW
NORMAL HIGH TEMPERATURES BOTH WEDNESDAY AND THURSDAY.
&&
.AVIATION...
12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR CONDITIONS ARE EXPECTED AT ALL TERMINALS TODAY. WEST TO
NORTHWEST WINDS WILL INCREASE INTO THE 15 TO 25 KNOT RANGE ACROSS
THE AREA BY 16Z AND WILL CONTINUE THROUGH SUNSET.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
SHORT TERM...DORN
LONG TERM...PARKIN
AVIATION...PARKIN
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
405 AM CST FRI JAN 6 2012
.SHORT TERM...TODAY THROUGH SUNDAY
THE FORECAST CHALLENGE IS TEMPERATURE.
CURRENTLY...LOW LEVEL CAA IS OCCURRING. 925HPA TEMPS HAVE FALLEN 5C
TO 10C DEGREES OVER THE PAST 6 HOURS. TEMPERATURES ARE STEADY OR
SLOWLY FALLING MAINLY THROUGH THE 30S AMID A PARTLY CLOUDY SKY.
0.5KM WIND SPEEDS /PER RUC MODEL/ ARE 25 TO 40 KNOTS EARLY THIS
MORNING.
LOW LEVEL TEMPERATURES ARE CONTINUING TO COOL TODAY DOWN TO A
RANGE OF GENERALLY 0C TO +3C...WHICH IS ROUGHLY A 10C TO 15C DROP
IN 925HPA TEMPERATURES IN 24 HOURS. DIFFERENT FROM PREVIOUS DAYS
WHEN 0.5KM WIND SPEEDS WERE BETWEEN 25 AND 40 KNOTS...WIND SPEEDS
THAT STRONG TODAY WILL BE MIXING DOWN TO THE SURFACE MUCH MORE
EFFICIENTLY WHILE LOW LEVEL CAA IS ONGOING. SUSTAINED WINDS OF 15
TO 25 MPH WITH HIGHER GUSTS IS EXPECTED. HEADING INTO SATURDAY AND
SUNDAY...-2C TO +4C AIR AT 925HPA IS PROGGED TO RESIDE OVER THE
CWA. SO...BASICALLY LOOKING AT SIMILAR TEMPERATURES OVER THE NEXT
THREE DAYS...RANGING FROM THE UPPER 30S THROUGH THE MID 40S.
THE DRY FORECAST UNDER NW FLOW ALOFT ALSO PERSISTS THROUGH
SUNDAY...EVEN THOUGH A FEW SUBTLE S/W TROFS APPEAR TO WORK ACROSS
THE REGION.
.LONG TERM...SUNDAY NIGHT THROUGH WEDNESDAY
THE MODELS ARE IN REASONABLE AGREEMENT DURING THE LONG TERM
PERIOD...WITH JUST SOME DIFFERENCES CONCERNING PRECIPITATION
CHANCES TUESDAY NIGHT. LOOKING AT ANOTHER DECENT WARM UP EARLY IN
THE PERIOD AS THE REGION WILL BE UNDER UPPER LEVEL NORTHWEST FLOW
AND ON THE WAA SIDE OF A SURFACE TROUGH. HIGH TEMPERATURES IN THE
40S LOOK TO BE COMMON BOTH MONDAY AND TUESDAY. THE SURFACE
TROUGH/FRONT PUSHES ACROSS THE AREA TUESDAY EVENING AS AN UPPER
LEVEL SHORTWAVE SLIDES FROM CENTRAL CANADA TO THE GREAT LAKES BY
THURSDAY MORNING. THE BEST ENERGY LOOKS TO AFFECT THE CWA TUESDAY
NIGHT INTO EARLY WEDNESDAY. MODEL TIME SECTIONS SHOW PRETTY GOOD
LIFT...BUT NOT MUCH IN THE WAY OF LOWER TO MID LEVEL MOISTURE.
THE GFS IS THE LEAST AGGRESSIVE MODEL WITH THE PRECIPITATION...WHILE
THE ECMWF INDICATES THE POTENTIAL FOR AN INCH OR SO OF
ACCUMULATION. TOO MANY DIFFERENCES RIGHT NOW...SO WILL JUST STICK
WITH THE ALLBLEND SLIGHT CHANCE POPS. HIGH PRESSURE QUICKLY MOVES
IN BEHIND THE EXITING SYSTEM...AND LOOKS TO BRING MUCH COOLER AIR
THAN WE HAVE SEEN RECENTLY BACK TO THE REGION. H85 TEMPS FALL INTO
THE -6 TO -19 DEGREE RANGE ON WEDNESDAY...AND REMAIN COLD INTO THE
DAY THURSDAY...WITH THE POSSIBILITY OF NEAR TO SLIGHTLY BELOW
NORMAL HIGH TEMPERATURES BOTH WEDNESDAY AND THURSDAY.
&&
.AVIATION...
06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR CONDITIONS ARE EXPECTED AT ALL TERMINALS THROUGH TONIGHT AND
FRIDAY. WEST TO NORTHWEST WINDS AT 15 TO 20 KNOTS WITH GUSTS TO 25
TO 30 KNOTS ARE EXPECTED AT ALL LOCATIONS BY 17Z...CONTINUING
THROUGH 23Z.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
SHORT TERM...DORN
LONG TERM...PARKIN
AVIATION...MOHR
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
930 PM CST SAT JAN 7 2012
.UPDATE...
SURFACE FRONT HAS COMPLETELY PUSHED THROUGH THE EASTERN COUNTIES
OF THE CWA NOW WITH LIGHT WINDS LESS THAN 5 MPH ACROSS MOST OF THE
REGION. SURFACE WINDS WILL REMAIN LIGHT OVERNIGHT BUT START TO
INCREASE FROM THE NORTH BY DAYBREAK AS ANOTHER SURFACE HIGH MOVES
ACROSS THE PLAINS. SURFACE DEWPOINTS ARE NOT EXPECTED TO CHANGE
MUCH OVERNIGHT THUS KEEPING WARMER OVERNIGHT LOWS IN THE 40S
ACROSS THE EASTERN COUNTIES WHILE THE WESTERN COUNTIES COOL INTO
THE 30S AGAIN. DENSE HIGH CLOUD COVER IS OVERSPREADING THE REGION
FROM THE SOUTHWEST...AHEAD OF THE UPPER LEVEL TROUGH NOW DIGGING
INTO ARIZONA. DESPITE THE LIGHT WINDS...THINK THE DENSE CLOUD
COVER WILL PREVENT FOG FROM DEVELOPING OVER THE EASTERN HALF OF
THE REGION /WHERE HIGHER DEWPOINTS WILL REMAIN/ AND HAVE REMOVED
THE MENTION OF THE FOG FROM THE FORECAST. LOW CLOUD COVER WILL
LIKELY CONTINUE TO PERSIST OVER THE NORTHEASTERN AND NORTHERN
COUNTIES OF NORTH TEXAS. ALSO FOR THE UPDATE...DID ADJUST
OVERNIGHT LOWS IN SEVERAL LOCATIONS BASED ON THE LATEST
TEMPERATURE TRENDS AND CHANGES TO THE DEWPOINTS DURING THE
OVERNIGHT PERIOD.
82/JLD
&&
.AVIATION...
ESSENTIALLY NO CONFIDENCE WITH THE CIG FORECAST DURING THE NEXT 24
HOURS FOR THE METROPLEX SITES AND AMENDMENTS WILL BE MADE AS
TRENDS BECOME APPARENT.
THE FINGER OF WRAP AROUND MVFR STRATUS IS SLOW TO LEAVE THE
METROPLEX BUT SHOULD CONTINUE TO SLOWLY ERODE BETWEEN 1-4Z WITH
DFW AND AFW LIKELY LAST TO CLEAR. THEN THE CONCERN SHIFTS TO THE
NORTHEAST AFTER MIDNIGHT WHERE EITHER A FOG BANK OR A LIFR/IFR
CLOUD DECK SHOULD DEVELOP. IF THE SURFACE LOW THAT IS OVER THE
EASTERN METROPLEX REMAINS IN ITS CURRENT POSITION...THIS WILL
BRING SOME OF THIS LOW LEVEL MOISTURE/FOG/CLOUDS INTO THE
METROPLEX AS THE NAM/HRRR/4KM WRF SHOW. THE RUC SHOWS THE
SURFACE LOW DRIFTING NORTH AND KEEPS ANY POTENTIAL FOR CIGS NORTH
OF THE REGION. GFS SHOWS SOUTHEAST WINDS WITH VFR PREVAILING. IF
THE LOW CIGS DO MAKE IT INTO THE TAF SITES TONIGHT...THEN THEY MAY
PERSISTS ALL DAY TOMORROW. WILL JUST COMPROMISE ALL OF THESE
SOLUTIONS AND FORECAST A 2000FT CIG TOMORROW FROM 12Z-18Z TO HINT
THAT IT MAY NOT BE VFR...EVEN THOUGH A CIG AT THIS HEIGHT AND FOR
THIS TIMEFRAME IS NOT LIKELY.
WACO WILL BE IN THE CLEAR AND HAVE VFR THROUGH THE PERIOD...BUT
SOME 3500FT CIGS SHOULD DEVELOP BY SUNRISE AND PERSIST INTO TOMORROW.
WINDS WILL BE NORTH AT 5-10KT THROUGH TOMORROW AT ALL SITES.
INCREASING HIGH-MID CLOUDS ARE EXPECTED TOMORROW...WITH ANY RAIN
LIKELY HOLDING OFF UNTIL SUNDAY NIGHT.
TR.92
&&
.PREV DISCUSSION... /ISSUED 321 PM CST SAT JAN 7 2012/
THE WEAK COLD FRONT HAS SLOWED DRAMATICALLY ACROSS EAST TEXAS AND
OUR THE SOUTHEAST COUNTIES TODAY WITH MINIMAL PRESSURE RISES BEHIND
THE FRONT. A WEAK INVERTED TROUGH IN THE 925-850MB LAYER HAS BEEN
NEARLY STATIONARY AS WELL OVER THE I-35 CORRIDOR/RED RIVER VALLEY
ALL DAY. THIS HAS RESULTED IN WEAK ISENTROPIC ASCENT THAT IS
HOLDING STRATUS OVER NORTHERN COUNTIES AND MAKING THE FORECAST
DIFFICULT WITH REGARD TO CLOUD COVER AND TEMPERATURES. MEANWHILE
AN UPPER DISTURBANCE CONTINUES TO INTENSIFY AND DEEPEN OVER THE
CENTRAL ROCKIES.
THE HRRR/WRF AND RUC BAK40 SOUNDINGS ALL INDICATE AT LEAST SOME
POTENTIAL FOR FOG DEVELOPING OVERNIGHT WITH WINDS BECOMING LIGHT
AND A TIGHT MOISTURE GRADIENT UP THROUGH THE BOUNDARY LAYER
THROUGH MIDDAY SUNDAY. WE ARE INSERTING PATCHY FOG EAST OF A
BOWIE...MINERAL WELLS...KILLEEN LINE WITH MORE COVERAGE OF LIGHT
FOG ACROSS THE NORTHEAST COUNTIES. TOO DIFFICULT TO ASCERTAIN IF
ANY FOG WILL BE DENSE AT THIS TIME. ANY FOG SHOULD DISSIPATE BY
AFTERNOON AS NORTH WINDS MIX TO AROUND 10 MPH OR SLIGHTLY HIGHER
THOUGH SOUTHEAST COUNTIES WILL HAVE LIGHTER NORTHEAST WINDS.
ISENTROPIC LIFT BEGINS OVER THE STALLED FRONTAL BOUNDARY SUNDAY
AFTERNOON IN DEVELOPING WAA REGIME ACROSS OUR SOUTHEAST COUNTIES.
THE ROCKIES DISTURBANCE WILL DEEPEN AND CLOSE OFF OVER AZ/NM AS
WELL. LIGHT RAIN SHOULD SLOWLY DEVELOP ACROSS THE SOUTHEAST BY
AFTERNOON...THEN OVERSPREAD NORTH TEXAS SUNDAY NIGHT AND MONDAY
AS ISENTROPIC ASCENT INCREASES WITH PLENTY OF FETCH FROM THE GULF
OF MEXICO. A GOOD STEADY RAIN IS EXPECTED INTO MONDAY EVENING.
1-2 INCHES OF BENEFICIAL RAINFALL WILL LIKELY OCCUR OVER THE FULL
DURATION WITH ISOLATED AMOUNTS IN EXCESS OF 3 INCHES POSSIBLE
ACROSS FAR SOUTHEASTERN AREAS. HAVE MAINTAINED ISOLATED/EMBEDDED
THUNDERSTORMS WITH LARGE-SCALE LIFT INTENSIFYING AND LAPSE RATES
ALOFT INCREASING TO NEAR 7 DEG/C.
THE UPPER LOW SLIDES OVER WEST TX BY MONDAY EVENING...THEN MODELS
CONTINUE TO DIVERGE ON ACTUAL STRENGTH/TRACK MONDAY NIGHT AND TUESDAY.
WILL USE A MEAN OF THE TRACKS WITH COLDEST AIR ALOFT TRACKING
ACROSS AREAS JUST NORTHWEST OF THE DFW METROPLEX. WITH THIS IN
MIND...A RAIN/SNOW SHOWER MIX COULD OCCUR WITH DYNAMIC COOLING AND
COLDER SURFACE TEMPERATURES ACROSS THE HIGHER TERRAIN OF THE
WESTERN COUNTIES. BOTH SURFACE AND GROUND TEMPERATURES WILL
REMAIN WELL ABOVE FREEZING BUT PROFILES ALOFT MAY SUPPORT SOME
SNOW MIXING IN WITH THE RAIN. IF ANY MINOR ACCUMULATIONS WERE TO
OCCUR...IT WOULD BE MINOR AND BRIEF ON ELEVATED SURFACES OR
GRASSY AREAS. DETAILS REMAIN FUZZY WE DO NOT EXPECT A MAJOR
WINTER EVENT WITH THIS SYSTEM. A DRY NOSE DOES APPEAR TO ARRIVE
TUESDAY FROM THE SOUTHWEST AND GET INGESTED INTO THE SYSTEM WITH
PRECIPITATION CHANCES LOWERING QUICKLY FROM SOUTH TO NORTH AS THE
UPPER LOW LIFTS TOWARD THE OZARKS AND MISSISSIPPI VALLEY BY
TUESDAY NIGHT.
A STRONGER COLD FRONT TAPPING AIR FROM ALASKA AND WESTERN CANADA
ARRIVES THURSDAY/FRIDAY A STEEP UPPER RIDGE ACROSS THE WESTERN
STATES AND A DEEP TROUGH OVER THE GREAT LAKES AND MISSISSIPPI
VALLEY. MEANWHILE...THE GFS AND ECMWF AS SWAPPED SOLUTIONS
REGARDING A POSSIBLE SOUTHERN PIECE OF ENERGY MOVING ACROSS RIGHT
AROUND THAT TIME FRAME. FOR NOW...WE ARE MAINTAINING A DRY...BRISK
AND COLD FORECAST AND UNDERCUTTING MOS TEMPERATURES BY A GOOD 5
DEGREES OR MORE PER PATTERN RECOGNITION. IT IS POSSIBLE THAT HIGHS
MAY NEED TO BE LOWERED IN UPCOMING FORECASTS IF IT BECOMES EVIDENT
THAT THIS IS TRUE ARCTIC AIR ORIGIN.
WE WILL CONTINUE TO FINE TUNE THE LATE WEEK FORECAST ONCE WE GET
PAST OUR FIRST SYSTEM FOR THE EARLY PART OF THE WEEK.
05/
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 43 57 44 46 40 / 0 10 80 100 70
WACO, TX 41 63 46 49 39 / 0 20 90 100 50
PARIS, TX 46 56 43 51 40 / 5 20 70 100 90
DENTON, TX 41 55 39 44 38 / 5 10 70 90 80
MCKINNEY, TX 42 57 41 47 39 / 5 10 70 100 80
DALLAS, TX 44 58 45 47 41 / 0 10 80 100 70
TERRELL, TX 43 58 46 50 40 / 5 20 80 100 80
CORSICANA, TX 44 61 48 53 41 / 5 20 90 100 70
TEMPLE, TX 40 65 46 49 39 / 0 20 90 100 40
MINERAL WELLS, TX 36 57 37 42 36 / 0 10 70 90 60
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
92/82
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
549 PM CST SAT JAN 7 2012
.AVIATION...
ESSENTIALLY NO CONFIDENCE WITH THE CIG FORECAST DURING THE NEXT 24
HOURS FOR THE METROPLEX SITES AND AMENDMENTS WILL BE MADE AS
TRENDS BECOME APPARENT.
THE FINGER OF WRAP AROUND MVFR STRATUS IS SLOW TO LEAVE THE
METROPLEX BUT SHOULD CONTINUE TO SLOWLY ERODE BETWEEN 1-4Z WITH
DFW AND AFW LIKELY LAST TO CLEAR. THEN THE CONCERN SHIFTS TO THE
NORTHEAST AFTER MIDNIGHT WHERE EITHER A FOG BANK OR A LIFR/IFR
CLOUD DECK SHOULD DEVELOP. IF THE SURFACE LOW THAT IS OVER THE
EASTERN METROPLEX REMAINS IN ITS CURRENT POSITION...THIS WILL
BRING SOME OF THIS LOW LEVEL MOISTURE/FOG/CLOUDS INTO THE
METROPLEX AS THE NAM/HRRR/4KM WRF SHOW. THE RUC SHOWS THE
SURFACE LOW DRIFTING NORTH AND KEEPS ANY POTENTIAL FOR CIGS NORTH
OF THE REGION. GFS SHOWS SOUTHEAST WINDS WITH VFR PREVAILING. IF
THE LOW CIGS DO MAKE IT INTO THE TAF SITES TONIGHT...THEN THEY MAY
PERSISTS ALL DAY TOMORROW. WILL JUST COMPROMISE ALL OF THESE
SOLUTIONS AND FORECAST A 2000FT CIG TOMORROW FROM 12Z-18Z TO HINT
THAT IT MAY NOT BE VFR...EVEN THOUGH A CIG AT THIS HEIGHT AND FOR
THIS TIMEFRAME IS NOT LIKELY.
WACO WILL BE IN THE CLEAR AND HAVE VFR THROUGH THE PERIOD...BUT
SOME 3500FT CIGS SHOULD DEVELOP BY SUNRISE AND PERSIST INTO TOMORROW.
WINDS WILL BE NORTH AT 5-10KT THROUGH TOMORROW AT ALL SITES.
INCREASING HIGH-MID CLOUDS ARE EXPECTED TOMORROW...WITH ANY RAIN
LIKELY HOLDING OFF UNTIL SUNDAY NIGHT.
TR.92
&&
.PREV DISCUSSION... /ISSUED 321 PM CST SAT JAN 7 2012/
THE WEAK COLD FRONT HAS SLOWED DRAMATICALLY ACROSS EAST TEXAS AND
OUR THE SOUTHEAST COUNTIES TODAY WITH MINIMAL PRESSURE RISES BEHIND
THE FRONT. A WEAK INVERTED TROUGH IN THE 925-850MB LAYER HAS BEEN
NEARLY STATIONARY AS WELL OVER THE I-35 CORRIDOR/RED RIVER VALLEY
ALL DAY. THIS HAS RESULTED IN WEAK ISENTROPIC ASCENT THAT IS
HOLDING STRATUS OVER NORTHERN COUNTIES AND MAKING THE FORECAST
DIFFICULT WITH REGARD TO CLOUD COVER AND TEMPERATURES. MEANWHILE
AN UPPER DISTURBANCE CONTINUES TO INTENSIFY AND DEEPEN OVER THE
CENTRAL ROCKIES.
THE HRRR/WRF AND RUC BAK40 SOUNDINGS ALL INDICATE AT LEAST SOME
POTENTIAL FOR FOG DEVELOPING OVERNIGHT WITH WINDS BECOMING LIGHT
AND A TIGHT MOISTURE GRADIENT UP THROUGH THE BOUNDARY LAYER
THROUGH MIDDAY SUNDAY. WE ARE INSERTING PATCHY FOG EAST OF A
BOWIE...MINERAL WELLS...KILLEEN LINE WITH MORE COVERAGE OF LIGHT
FOG ACROSS THE NORTHEAST COUNTIES. TOO DIFFICULT TO ASCERTAIN IF
ANY FOG WILL BE DENSE AT THIS TIME. ANY FOG SHOULD DISSIPATE BY
AFTERNOON AS NORTH WINDS MIX TO AROUND 10 MPH OR SLIGHTLY HIGHER
THOUGH SOUTHEAST COUNTIES WILL HAVE LIGHTER NORTHEAST WINDS.
ISENTROPIC LIFT BEGINS OVER THE STALLED FRONTAL BOUNDARY SUNDAY
AFTERNOON IN DEVELOPING WAA REGIME ACROSS OUR SOUTHEAST COUNTIES.
THE ROCKIES DISTURBANCE WILL DEEPEN AND CLOSE OFF OVER AZ/NM AS
WELL. LIGHT RAIN SHOULD SLOWLY DEVELOP ACROSS THE SOUTHEAST BY
AFTERNOON...THEN OVERSPREAD NORTH TEXAS SUNDAY NIGHT AND MONDAY
AS ISENTROPIC ASCENT INCREASES WITH PLENTY OF FETCH FROM THE GULF
OF MEXICO. A GOOD STEADY RAIN IS EXPECTED INTO MONDAY EVENING.
1-2 INCHES OF BENEFICIAL RAINFALL WILL LIKELY OCCUR OVER THE FULL
DURATION WITH ISOLATED AMOUNTS IN EXCESS OF 3 INCHES POSSIBLE
ACROSS FAR SOUTHEASTERN AREAS. HAVE MAINTAINED ISOLATED/EMBEDDED
THUNDERSTORMS WITH LARGE-SCALE LIFT INTENSIFYING AND LAPSE RATES
ALOFT INCREASING TO NEAR 7 DEG/C.
THE UPPER LOW SLIDES OVER WEST TX BY MONDAY EVENING...THEN MODELS
CONTINUE TO DIVERGE ON ACTUAL STRENGTH/TRACK MONDAY NIGHT AND TUESDAY.
WILL USE A MEAN OF THE TRACKS WITH COLDEST AIR ALOFT TRACKING
ACROSS AREAS JUST NORTHWEST OF THE DFW METROPLEX. WITH THIS IN
MIND...A RAIN/SNOW SHOWER MIX COULD OCCUR WITH DYNAMIC COOLING AND
COLDER SURFACE TEMPERATURES ACROSS THE HIGHER TERRAIN OF THE
WESTERN COUNTIES. BOTH SURFACE AND GROUND TEMPERATURES WILL
REMAIN WELL ABOVE FREEZING BUT PROFILES ALOFT MAY SUPPORT SOME
SNOW MIXING IN WITH THE RAIN. IF ANY MINOR ACCUMULATIONS WERE TO
OCCUR...IT WOULD BE MINOR AND BRIEF ON ELEVATED SURFACES OR
GRASSY AREAS. DETAILS REMAIN FUZZY WE DO NOT EXPECT A MAJOR
WINTER EVENT WITH THIS SYSTEM. A DRY NOSE DOES APPEAR TO ARRIVE
TUESDAY FROM THE SOUTHWEST AND GET INGESTED INTO THE SYSTEM WITH
PRECIPITATION CHANCES LOWERING QUICKLY FROM SOUTH TO NORTH AS THE
UPPER LOW LIFTS TOWARD THE OZARKS AND MISSISSIPPI VALLEY BY
TUESDAY NIGHT.
A STRONGER COLD FRONT TAPPING AIR FROM ALASKA AND WESTERN CANADA
ARRIVES THURSDAY/FRIDAY A STEEP UPPER RIDGE ACROSS THE WESTERN
STATES AND A DEEP TROUGH OVER THE GREAT LAKES AND MISSISSIPPI
VALLEY. MEANWHILE...THE GFS AND ECMWF AS SWAPPED SOLUTIONS
REGARDING A POSSIBLE SOUTHERN PIECE OF ENERGY MOVING ACROSS RIGHT
AROUND THAT TIME FRAME. FOR NOW...WE ARE MAINTAINING A DRY...BRISK
AND COLD FORECAST AND UNDERCUTTING MOS TEMPERATURES BY A GOOD 5
DEGREES OR MORE PER PATTERN RECOGNITION. IT IS POSSIBLE THAT HIGHS
MAY NEED TO BE LOWERED IN UPCOMING FORECASTS IF IT BECOMES EVIDENT
THAT THIS IS TRUE ARCTIC AIR ORIGIN.
WE WILL CONTINUE TO FINE TUNE THE LATE WEEK FORECAST ONCE WE GET
PAST OUR FIRST SYSTEM FOR THE EARLY PART OF THE WEEK.
05/
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 43 57 44 46 40 / 5 10 80 100 70
WACO, TX 39 63 46 49 39 / 10 20 90 100 50
PARIS, TX 45 56 43 51 40 / 10 20 70 100 90
DENTON, TX 36 55 39 44 38 / 10 10 70 90 80
MCKINNEY, TX 38 57 41 47 39 / 10 10 70 100 80
DALLAS, TX 44 58 45 47 41 / 5 10 80 100 70
TERRELL, TX 42 58 46 50 40 / 10 20 80 100 80
CORSICANA, TX 42 61 48 53 41 / 10 20 90 100 70
TEMPLE, TX 40 65 46 49 39 / 10 20 90 100 40
MINERAL WELLS, TX 34 57 37 42 36 / 5 10 70 90 60
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1142 PM CST THU JAN 5 2012
.AVIATION...
SINCE THE 03Z DISCUSSION...HAVE BECOME LESS CONFIDENT ABOUT FOG
FORMATION TONIGHT...AND LESS CONFIDENT THAT LOW STRATUS WILL FORM.
THE WEAK WARM FRONT HAS BECOME VERY DIFFUSE WITH DEWPOINTS IN THE
50S NORTH OF THE FRONT AND LOWER 60S TO THE SOUTH. THE FRONT AT
04Z WAS LOCATED JUST NORTH OF KIAH AND ABOUT HALFWAY BETWEEN KCLL
AND KSGR. THE UPPER LOW OVER SOUTH TEXAS WAS HELPING TO DEVELOP
SHOWERS OFF THE TEXAS COASTAL BEND BEYOND 30 MILES OF THE COAST.
THE SHOWERS MAY AFFECT THE IMMEDIATE COASTAL AREAS AFTER 09Z.
THE 02Z RUC FORECAST SOUNDINGS REFLECT THE 00Z NAM12...WHICH LOOK
SIMILAR TO THE MODELS OF 24 HOURS AGO. THE 00Z GFS FORECAST
SOUNDINGS WERE ALONG THE SAME LINES. THESE FORECAST AN INVERSION
CLOSE TO THE SURFACE AND INDICATED SCATTERED TO BROKEN CONDITIONS
AT AROUND 4000 FEET DURING THE OVERNIGHT PERIOD INTO THE MORNING.
THE BEST TIME PERIOD FOR FOG TO FORM WILL BE AFTER 09Z WITH THE
MOST LIKELY LOCATIONS BEING AT KCXO AND KLBX. INSERTED A SCATTERED
DECK AT 1500 FEET WITH THE HINT AT MVFR CONDITIONS FOR ALL SITES
BEGINNING BETWEEN 09Z AND 12Z. IF MVFR CONDITIONS DO FORM...THESE
SHOULD LIFT AFTER 15Z. AT THIS TIME...IFR OR LOWER CONDITIONS DO
NOT LOOK TO BE LIKELY.
40
&&
.PREV DISCUSSION... /ISSUED 919 PM CST THU JAN 5 2012/
UPDATE...
SEE EVENING UPDATE BELOW.
DISCUSSION...
A WEAK BOUNDARY APPEARS TO BE RETREATING NORTH AS LIGHT SOUTH
WINDS HAVE RETURNED AS FAR NORTH AS IAH THIS EVENING. DEW PTS HAVE
BEGUN TO CREEP UPWARD AS WELL. RADAR IS SHOWING PRECIP INCREASING
IN COVERAGE OVER THE GULF...BUT THE TRAJECTORY OF THE PRECIP
SHOULD KEEP MOST OF THE RAIN OFFSHORE...OR PERHAPS JUST CLIPPING
THE COAST. TWEAKED MIN TEMP GRIDS TO RAISE THEM JUST A BIT DO TO
CLOUD COVER AND HIGHER DEW PTS. STILL LOOKS LIKE HIGH RAIN CHANCES
FOR SUN NITE/MON AS A STRONG UPPER LOW MOVES ACROSS THE STATE.
PATCHY FOG WILL BEGIN TO DEVELOP AFTER MIDNIGHT. THE BEST CHANCE
FOR FOG WILL LIKELY REMAIN SOUTH OF I-10 AND CLOSER TO THE COAST. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 51 72 54 69 52 / 10 10 10 10 10
HOUSTON (IAH) 57 74 58 74 58 / 20 20 10 10 10
GALVESTON (GLS) 60 68 59 71 60 / 20 30 20 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
341 PM CST FRI JAN 6 2012
.SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT
241 PM CST FRI JAN 6 2012
AT 3 PM...A COLD FRONT WAS LOCATED FROM SAULT STE MARIE MICHIGAN
TO LUBBOCK TEXAS. WITH THE AIR MASS BEING OF PACIFIC ORIGIN...
THERE WAS ONLY A SLIGHT DECREASE IN THE TEMPERATURES BEHIND THE
FRONT. TEMPERATURES ACROSS THE AREA WERE MAINLY IN THE 40S TODAY.
IF IT WERE NOT FOR THE EXTENSIVE MID CLOUDS ACROSS THE AREA...
TEMPERATURES MAY HAVE CLIMBED A FEW MORE DEGREES. WHERE SKIES HAVE
BEEN CLEARING /NORTH OF A DODGE CENTER MINNESOTA TO ESCANABA
MICHIGAN LINE/...TEMPERATURES HAVE CLIMBED A COUPLE OF DEGREES...
SO MAY CLIMB A FEW MORE DEGREES IN THE AREAS THAT CLEAR OUT LATE
THIS AFTERNOON.
TONIGHT...06.12Z MODELS ARE IN AGREEMENT THAT ANOTHER COLD FRONT
WILL MOVE SOUTHEAST THROUGH THE AREA. LIKE ITS PREDECESSOR...THIS
FRONT IS EXPECTED TO MOVE THROUGH THE REGION DRY. BEHIND THIS FRONT...
THERE WILL BE ANOTHER SLIGHT DROP IN TEMPERATURES. 925 MB
TEMPERATURES DROP FROM 2 TO 6C AHEAD OF THE FRONT TO -2 TO -6C
BEHIND THIS FRONT. LOW TEMPERATURES WILL FALL OFF INTO THE MID AND
UPPER 20S. THIS IS ABOUT 5 DEGREES WARMER THAN OUR NORMAL DAILY
HIGH TEMPERATURES FOR THIS TIME OF YEAR. IN ADDITION TO THE COOLER
TEMPERATURES...SOME LOW CLOUDS ARE MOVING SOUTHEAST TOWARD THE
AREA. WITH THEIR CURRENT TRAJECTORY...THINKING THAT THE BEST
CHANCE OF SEEING THESE CLOUDS WILL BE NORTHEAST OF A LAKE CITY
MINNESOTA TO THE WISCONSIN DELLS. THERE MAY BE EVEN A PERIOD OF
LIGHT SNOW OR FLURRIES NORTH OF THE INTERSTATE 94 CORRIDOR.
HOWEVER NO SNOW ACCUMULATIONS ARE EXPECTED.
ON SATURDAY...CLOUDS WILL LINGER ALONG AND NORTH OF THE INTERSTATE
94 CORRIDOR DURING THE MORNING AND GRADUALLY CLEAR DURING THE
AFTERNOON. THE COMBINATION OF THESE CLOUDS AND THE COOL 925 MB
TEMPERATURES WILL KEEP THESE TEMPERATURES IN THESE AREAS CONFINED
TO THE LOWER AND MID 30S. MEANWHILE THE REMAINDER OF THE AREA
WILL SEE TEMPERATURES IN THE UPPER 30S AND LOWER 40S.
ON SUNDAY NIGHT...A WARM FRONT WILL MOVE SOUTHEAST THROUGH THE
REGION. THE 925 MB TEMPERATURES WILL CLIMB FROM -2 TO -4C AHEAD OF
THIS FRONT TO 0 TO 4C BEHIND THIS FRONT. COLDEST TEMPERATURES ARE
EXPECTED DURING THE EVENING AND THEN EITHER REMAIN STEADY OR
SLOWLY CLIMB DURING THE OVERNIGHT. AS A RESULT...WENT WITH A NON
DIURNAL TEMPERATURE CURVE FOR THIS TIME PERIOD.
.LONG TERM...MONDAY THROUGH FRIDAY
241 PM CST FRI JAN 6 2012
FROM MONDAY INTO TUESDAY...925 MB TEMPERATURES WILL RANGE FROM
4 TO 8C. THIS IS JUST A FEW DEGREES COOLER THAN THEY WERE
YESTERDAY. AS A RESULT...EXPECT TO SEE A RETURN TO MUCH ABOVE
NORMAL TEMPERATURES. CURRENTLY WENT WITH HIGH TEMPERATURES ON BOTH
DAYS IN THE 40S...BUT WOULD NOT BE TOO SURPRISED THAT WE MAY SEE
ANOTHER ROUND OF 50 DEGREE TEMPERATURES.
ON WEDNESDAY...AN UPPER AIR PATTERN SHIFT BEGIN AS THE PACIFIC
NORTH AMERICAN /PNA/ TELECONNECTION BECOMES POSITIVE /WESTERN U.S.
RIDGE AND EASTERN U.S. TROUGH/. THIS WILL ALLOW MUCH COLDER AIR TO
SPILL SOUTHWARD INTO THE FORECAST AREA. UNLIKE THE 06.00Z
ECMWF WHERE IT SHOWED DECENT PRECIPITATION ASSOCIATED WITH A
CLOSED LOW...A MAJORITY OF 06.12Z NOW SUGGEST THAT THIS FRONT WILL
HAVE VERY LITTLE MOISTURE TO PRODUCE MUCH PRECIPITATION
THE TEMPERATURES BEHIND THE ARCTIC FRONT WILL BE INTI ALLY BELOW
NORMAL AND THEN WARM UP CLOSER TO NORMAL AS THE AIR MASS GRADUALLY
MODERATES. UNLIKE THE NEW YEARS FRONT...THIS COLD AIR MAY PERSIST
FOR SEVERAL INTO MID JANUARY. AS THE TROPICAL FORCING MOVES INTO
THE INDIAN OCEAN FROM THE AFRICAN CONTINENT...EXPECT TO ONCE AGAIN
SEE THE POLAR JET RETREAT BACK INTO SOUTHERN CANADA BRINGING A
RETURN TO THE UNSEASONABLE FOR THE LATTER PART OF JANUARY.
&&
.AVIATION...THROUGH 18Z SATURDAY
1135 AM CST FRI JAN 6 2012
AN AREA OF LOW PRESSURE WILL CONTINUE TO PUSH EAST AWAY FROM THE
AREA THROUGH TONIGHT. A VEIL OF HIGH CLOUDS OVER THE TAF SITES
WILL PUSH SOUTH THIS AFTERNOON/EVENING. BIGGEST CHALLENGE WILL
COME LATER THIS EVENING WHEN MODELS ARE SHOWING SOME STRATUS
DROPPING IN BEHIND A SURFACE TROUGH. CURRENTLY THESE CLOUDS ARE
ACROSS SOUTHERN CANADA/NORTHERN MINNESOTA. BOTH THE 06.15Z RUC AND
THE 06.12Z GFS AND NAM SHOWING THIS MOISTURE DROPPING SOUTHEAST
THIS EVENING. FEEL THE BETTER CHANCES FOR THE CLOUDS MAY EXIST TO
THE NORTHEAST OF THE TAF SITES BASED ON RELATIVE HUMIDITY
PROGS...BUT DID INTRODUCE A FEW-SCT DECK AT KRST AND KLSE
RESPECTIVELY WITH HEIGHTS OF 025K-030K FEET. THESE SHOULD ARRIVE
BETWEEN 04Z-06Z THIS EVENING AND PERSIST THROUGH 18Z SATURDAY.
LATER SHIFTS WILL HAVE TO MONITOR FOR POSSIBLE CEILINGS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
241 PM CST FRI JAN 6 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1135 AM CST FRI JAN 6 2012
.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
215 AM CST FRI JAN 6 2012
MAIN FORECAST CONCERNS ARE CLOUDS AND TEMPERATURES IN THIS ABOVE
NORMAL TEMPERATURE PATTERN.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED WEAK RIDGING ALONG THE WEST COAST OF THE U.S. AND BRITISH
COLUMBIA...A SHORTWAVE TROUGH OVER MONTANA...THEN NEARLY ZONAL FLOW
FROM THE DAKOTAS EASTWARD INTO NEW ENGLAND. AHEAD OF THE SHORTWAVE
TROUGH...A 90-110 KT JET WAS PRESENT FROM THE DAKOTAS INTO UPPER
MICHIGAN. THIS JET COMBINED WITH A STREAM OF PACIFIC MOISTURE IS
HELPING TO PRODUCE SCATTERED-BROKEN CIRRUS FROM SOUTH DAKOTA AND
NEBRASKA NORTHEASTWARD ACROSS THE FORECAST AREA. MOISTURE VERY HARD
TO COME BY BELOW THIS CIRRUS...NOTED BY 10C OR HIGHER DEWPOINT
DEPRESSIONS FROM THE SURFACE TO 500MB ON 00Z SOUNDINGS FROM
MPX...ABR AND BIS. 850MB TEMPS ON THESE SOUNDINGS RANGED FROM AROUND
10C AT ABR AND MPX...WHILE A COOLER READING OF 7C WAS REPORTED AT
BIS. BIS WAS LOCATED BEHIND A COLD FRONT WHICH CURRENTLY EXTENDS
FROM DES MOINES IOWA INTO NORTHEAST WISCONSIN. 925MB VAD WIND PROFILER
DATA DEPICTS 30-40 KT NORTHWEST WINDS IN THE WAKE OF THE FRONT.
DESPITE THIS COLD ADVECTION...THE WINDS IN CONJUNCTION WITH THE
CLOUDS AND GENERALLY MILD AIRMASS BEHIND THE FRONT...HAS HELPED TO
KEEP TEMPERATURES UP IN THE 30S AND INTO THE LOW 40S.
TODAY AND TONIGHT...SHORTWAVE TROUGH OVER MONTANA IS FORECAST BY ALL
MODELS TO MOVE ACROSS THE FORECAST AREA TONIGHT...THOUGH THE CRUX OF
THE TROUGH LOOKS TO AFFECT UPPER MICHIGAN. AS THE TROUGH APPROACHES
THE AREA TODAY...THE UPPER JET STREAK SEEN AHEAD OF IT WILL SLOWLY
SINK TO THE SOUTHEAST...AND THEREFORE SO WILL THE SCATTERED-BROKEN
CIRRUS. ALONG WITH THE SLOW DECREASE IN CLOUDS FROM THE NORTHWEST TO
SOUTHEAST...THE APPROACH OF THE TROUGH ALONG WITH THE PASSAGE OF THE
CURRENT COLD FRONT MEANS COLD ADVECTION TODAY. STILL...THE COLD
ADVECTION IS GRADUAL...NOTED BY 925MB TEMPS WHICH START OFF AT 6-8C
AT 12Z AND ONLY FALL TO 1-4C BY 00Z. SUNSHINE THROUGH THE HIGH
CLOUDS...WINDS TO HELP WITH MIXING...MOSTLY A LACK OF SNOW EXCEPT
NORTH OF I-94...AND A WARM START OFF SHOULD YIELD ANOTHER WELL ABOVE
NORMAL DAY TODAY. MOST AREAS SHOULD AT LEAST SEE HIGHS IN THE 40S
WITH SOME LOCATIONS REACHING INTO THE LOWER 50S. A LITTLE COOLER AIR
COMES IN TONIGHT WITH 925MB TEMPS FALLING TO -2 TO -5C BY 12Z
SATURDAY. SOME LOW CLOUDS MAY ACCOMPANY THIS COOLING AND DROP DOWN
INTO NORTH CENTRAL WISCONSIN...BUT NO LIFT IS PRESENT WITHIN THE
CLOUD LAYER TO PRODUCE PRECIPITATION. GENERALLY FOLLOWED A BLEND OF
GUIDANCE FOR LOWS.
SATURDAY THROUGH SUNDAY NIGHT...SHORTWAVE TROUGH OVER THE AREA
TONIGHT IS PROGGED TO SCOOT OFF TO THE EAST ON SATURDAY...LEAVING
THE AREA IN WEAK BROAD TROUGHING. THERE ARE INDICATIONS OF ANOTHER
SHORTWAVE TROUGH COMING THROUGH THE AREA SUNDAY NIGHT...IN ADVANCE
OF RIDGING BUILDING UP ACROSS THE NORTHERN ROCKIES INTO SOUTHWEST
CANADA. NONE OF THESE FEATURES ARE EXPECTED TO PRODUCE ANY
PRECIPITATION...DUE TO THE PRESENCE OF TOO MUCH DRY AIR. THERE WILL
BE PERIODS OF CLOUDS AFFECTING THE AREA...HOWEVER. THE FIRST IS
ALONG AND NORTH OF I-94...WHERE LOW CLOUDS ARE POSSIBLE SATURDAY
INTO SATURDAY NIGHT. THESE CLOUDS ARE ASSOCIATED WITH THE LOW LEVEL
COOLING LEFT BEHIND FROM TONIGHTS SHORTWAVE TROUGH. ANTICIPATING
THESE CLOUDS TO CLEAR OUT ON SUNDAY AS WARM/DRY ADVECTION SURGES IN
FROM THE PLAINS. THIS SAME ADVECTION ON THE OTHER HAND DOES LOOK
TO PRODUCE SOME MID/HIGH CLOUDS...MAINLY SATURDAY NIGHT AND SUNDAY
ACROSS THE SOUTHERN 2/3 OF THE AREA. THESE CLOUDS SHOULD CLEAR OUT
SUNDAY NIGHT AS THE NEXT SHORTWAVE TROUGH MOVES THROUGH. REGARDING
TEMPERATURES...925MB READINGS ARE PROGGED TO HOLD FAIRLY STEADY
THROUGH SUNDAY MORNING...BETWEEN -2 AND -6C...THEN SLOWLY START
RISING TO AROUND 0C BY 12Z MONDAY AS THE NEXT SHORTWAVE TROUGH COMES
THROUGH. THIS MEANS THE WEEKEND WILL BE COOLER...BUT STILL ABOVE
NORMAL. A BLEND OF GUIDANCE WITH A LEAN TOWARDS THE ECMWF SEEMS
APPROPRIATE...SINCE THE ECMWF HAS BEEN DOING WELL IN THIS ABOVE
NORMAL PATTERN.
.LONG TERM...MONDAY THROUGH THURSDAY NIGHT
215 AM CST FRI JAN 6 2012
06.00Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES REMAIN IN GOOD AGREEMENT
WITH PREVIOUS RUNS AND WITH EACH OTHER ON THE UPCOMING WEATHER
PATTERN FOR NEXT WEEK. THERE ARE SOME TIMING DIFFERENCES FOR THE
MIDDLE OF THE WEEK...BUT IN GENERAL THEY DEPICT A WELL AGREED UPON
PATTERN. MONDAY AND TUESDAY FEATURE WELL ABOVE NORMAL WARMTH
AGAIN...IN RESPONSE TO THE BUILDING RIDGING OVER THE NORTHERN
ROCKIES ON SUNDAY NIGHT BEING FLATTENED AND SENT EASTWARD THROUGH
THE FORECAST AREA. 925MB TEMPS RESPOND BY JUMPING FROM THE 0C AT 12Z
MONDAY TO 2-4C AT 00Z TUESDAY...THEN HOVERING AROUND THOSE LEVELS
THROUGH THE DAY TUESDAY. DRY CONDITIONS ARE FORECAST WITH
TEMPERATURES CLOSE TO ECMWF PROGGED VALUES. PATTERN CHANGES COME
LATER TUESDAY AS A POTENT TROUGH DIGS DOWN INTO ALBERTA AND
SASKATCHEWAN. THIS TROUGH ALL MODELS HAVE DIGGING DOWN INTO THE
UPPER MIDWEST FOR WEDNESDAY AND THURSDAY...BUT AGAIN THE TIMING
VARIES. THE 06.00Z GFS/GFS ENSEMBLES/CANADIAN ALL BRING IT INTO THE
FORECAST AREA LATE WEDNESDAY...WHEREAS THE 05.12Z ECMWF STILL HAS IT
BACK OVER THE DAKOTAS AT THE SAME TIME. FOR NOW HAVE FOLLOWED A
CONSENSUS BLEND UNTIL THE TIMING CAN SORT ITSELF OUT. 850MB TEMPS
PLUMMET WITHIN THE TROUGH...DROPPING TO -12 TO PERHAPS AS COLD AS
-20C UNDER THE CORE OF IT. SO CERTAINLY MORE WINTER LIKE AIR WILL
END UP MOVING INTO THE FORECAST AREA. PRECIPITATION ON THE OTHER
HAND IS MUCH MORE UNCERTAIN...DUE TO MOST OF THE MOISTURE TRAPPED
WITH A SYSTEM TRACKING ALONG THE GULF COAST INTO THE MID-ATLANTIC
STATES. THERE IS SOME AGREEMENT ON A BAND OF DEFORMATION AND DPVA
FORCED PRECIPITATION AHEAD OF THE TROUGH...BUT UNCERTAINTIES ON
TIMING AND AVAILABLE MOISTURE RESULT IN NO HIGHER THAN 20-30 PERCENT
CHANCES AT THIS TIME.
&&
.AVIATION...THROUGH 18Z SATURDAY
1135 AM CST FRI JAN 6 2012
AN AREA OF LOW PRESSURE WILL CONTINUE TO PUSH EAST AWAY FROM THE
AREA THROUGH TONIGHT. A VEIL OF HIGH CLOUDS OVER THE TAF SITES
WILL PUSH SOUTH THIS AFTERNOON/EVENING. BIGGEST CHALLENGE WILL
COME LATER THIS EVENING WHEN MODELS ARE SHOWING SOME STRATUS
DROPPING IN BEHIND A SURFACE TROUGH. CURRENTLY THESE CLOUDS ARE
ACROSS SOUTHERN CANADA/NORTHERN MINNESOTA. BOTH THE 06.15Z RUC AND
THE 06.12Z GFS AND NAM SHOWING THIS MOISTURE DROPPING SOUTHEAST
THIS EVENING. FEEL THE BETTER CHANCES FOR THE CLOUDS MAY EXIST TO
THE NORTHEAST OF THE TAF SITES BASED ON RELATIVE HUMIDITY
PROGS...BUT DID INTRODUCE A FEW-SCT DECK AT KRST AND KLSE
RESPECTIVELY WITH HEIGHTS OF 025K-030K FEET. THESE SHOULD ARRIVE
BETWEEN 04Z-06Z THIS EVENING AND PERSIST THROUGH 18Z SATURDAY.
LATER SHIFTS WILL HAVE TO MONITOR FOR POSSIBLE CEILINGS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
215 AM CST FRI JAN 6 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
515 AM CST FRI JAN 6 2012
.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
215 AM CST FRI JAN 6 2012
MAIN FORECAST CONCERNS ARE CLOUDS AND TEMPERATURES IN THIS ABOVE
NORMAL TEMPERATURE PATTERN.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED WEAK RIDGING ALONG THE WEST COAST OF THE U.S. AND BRITISH
COLUMBIA...A SHORTWAVE TROUGH OVER MONTANA...THEN NEARLY ZONAL FLOW
FROM THE DAKOTAS EASTWARD INTO NEW ENGLAND. AHEAD OF THE SHORTWAVE
TROUGH...A 90-110 KT JET WAS PRESENT FROM THE DAKOTAS INTO UPPER
MICHIGAN. THIS JET COMBINED WITH A STREAM OF PACIFIC MOISTURE IS
HELPING TO PRODUCE SCATTERED-BROKEN CIRRUS FROM SOUTH DAKOTA AND
NEBRASKA NORTHEASTWARD ACROSS THE FORECAST AREA. MOISTURE VERY HARD
TO COME BY BELOW THIS CIRRUS...NOTED BY 10C OR HIGHER DEWPOINT
DEPRESSIONS FROM THE SURFACE TO 500MB ON 00Z SOUNDINGS FROM
MPX...ABR AND BIS. 850MB TEMPS ON THESE SOUNDINGS RANGED FROM AROUND
10C AT ABR AND MPX...WHILE A COOLER READING OF 7C WAS REPORTED AT
BIS. BIS WAS LOCATED BEHIND A COLD FRONT WHICH CURRENTLY EXTENDS
FROM DES MOINES IOWA INTO NORTHEAST WISCONSIN. 925MB VAD WIND PROFILER
DATA DEPICTS 30-40 KT NORTHWEST WINDS IN THE WAKE OF THE FRONT.
DESPITE THIS COLD ADVECTION...THE WINDS IN CONJUNCTION WITH THE
CLOUDS AND GENERALLY MILD AIRMASS BEHIND THE FRONT...HAS HELPED TO
KEEP TEMPERATURES UP IN THE 30S AND INTO THE LOW 40S.
TODAY AND TONIGHT...SHORTWAVE TROUGH OVER MONTANA IS FORECAST BY ALL
MODELS TO MOVE ACROSS THE FORECAST AREA TONIGHT...THOUGH THE CRUX OF
THE TROUGH LOOKS TO AFFECT UPPER MICHIGAN. AS THE TROUGH APPROACHES
THE AREA TODAY...THE UPPER JET STREAK SEEN AHEAD OF IT WILL SLOWLY
SINK TO THE SOUTHEAST...AND THEREFORE SO WILL THE SCATTERED-BROKEN
CIRRUS. ALONG WITH THE SLOW DECREASE IN CLOUDS FROM THE NORTHWEST TO
SOUTHEAST...THE APPROACH OF THE TROUGH ALONG WITH THE PASSAGE OF THE
CURRENT COLD FRONT MEANS COLD ADVECTION TODAY. STILL...THE COLD
ADVECTION IS GRADUAL...NOTED BY 925MB TEMPS WHICH START OFF AT 6-8C
AT 12Z AND ONLY FALL TO 1-4C BY 00Z. SUNSHINE THROUGH THE HIGH
CLOUDS...WINDS TO HELP WITH MIXING...MOSTLY A LACK OF SNOW EXCEPT
NORTH OF I-94...AND A WARM START OFF SHOULD YIELD ANOTHER WELL ABOVE
NORMAL DAY TODAY. MOST AREAS SHOULD AT LEAST SEE HIGHS IN THE 40S
WITH SOME LOCATIONS REACHING INTO THE LOWER 50S. A LITTLE COOLER AIR
COMES IN TONIGHT WITH 925MB TEMPS FALLING TO -2 TO -5C BY 12Z
SATURDAY. SOME LOW CLOUDS MAY ACCOMPANY THIS COOLING AND DROP DOWN
INTO NORTH CENTRAL WISCONSIN...BUT NO LIFT IS PRESENT WITHIN THE
CLOUD LAYER TO PRODUCE PRECIPITATION. GENERALLY FOLLOWED A BLEND OF
GUIDANCE FOR LOWS.
SATURDAY THROUGH SUNDAY NIGHT...SHORTWAVE TROUGH OVER THE AREA
TONIGHT IS PROGGED TO SCOOT OFF TO THE EAST ON SATURDAY...LEAVING
THE AREA IN WEAK BROAD TROUGHING. THERE ARE INDICATIONS OF ANOTHER
SHORTWAVE TROUGH COMING THROUGH THE AREA SUNDAY NIGHT...IN ADVANCE
OF RIDGING BUILDING UP ACROSS THE NORTHERN ROCKIES INTO SOUTHWEST
CANADA. NONE OF THESE FEATURES ARE EXPECTED TO PRODUCE ANY
PRECIPITATION...DUE TO THE PRESENCE OF TOO MUCH DRY AIR. THERE WILL
BE PERIODS OF CLOUDS AFFECTING THE AREA...HOWEVER. THE FIRST IS
ALONG AND NORTH OF I-94...WHERE LOW CLOUDS ARE POSSIBLE SATURDAY
INTO SATURDAY NIGHT. THESE CLOUDS ARE ASSOCIATED WITH THE LOW LEVEL
COOLING LEFT BEHIND FROM TONIGHTS SHORTWAVE TROUGH. ANTICIPATING
THESE CLOUDS TO CLEAR OUT ON SUNDAY AS WARM/DRY ADVECTION SURGES IN
FROM THE PLAINS. THIS SAME ADVECTION ON THE OTHER HAND DOES LOOK
TO PRODUCE SOME MID/HIGH CLOUDS...MAINLY SATURDAY NIGHT AND SUNDAY
ACROSS THE SOUTHERN 2/3 OF THE AREA. THESE CLOUDS SHOULD CLEAR OUT
SUNDAY NIGHT AS THE NEXT SHORTWAVE TROUGH MOVES THROUGH. REGARDING
TEMPERATURES...925MB READINGS ARE PROGGED TO HOLD FAIRLY STEADY
THROUGH SUNDAY MORNING...BETWEEN -2 AND -6C...THEN SLOWLY START
RISING TO AROUND 0C BY 12Z MONDAY AS THE NEXT SHORTWAVE TROUGH COMES
THROUGH. THIS MEANS THE WEEKEND WILL BE COOLER...BUT STILL ABOVE
NORMAL. A BLEND OF GUIDANCE WITH A LEAN TOWARDS THE ECMWF SEEMS
APPROPRIATE...SINCE THE ECMWF HAS BEEN DOING WELL IN THIS ABOVE
NORMAL PATTERN.
.LONG TERM...MONDAY THROUGH THURSDAY NIGHT
215 AM CST FRI JAN 6 2012
06.00Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES REMAIN IN GOOD AGREEMENT
WITH PREVIOUS RUNS AND WITH EACH OTHER ON THE UPCOMING WEATHER
PATTERN FOR NEXT WEEK. THERE ARE SOME TIMING DIFFERENCES FOR THE
MIDDLE OF THE WEEK...BUT IN GENERAL THEY DEPICT A WELL AGREED UPON
PATTERN. MONDAY AND TUESDAY FEATURE WELL ABOVE NORMAL WARMTH
AGAIN...IN RESPONSE TO THE BUILDING RIDGING OVER THE NORTHERN
ROCKIES ON SUNDAY NIGHT BEING FLATTENED AND SENT EASTWARD THROUGH
THE FORECAST AREA. 925MB TEMPS RESPOND BY JUMPING FROM THE 0C AT 12Z
MONDAY TO 2-4C AT 00Z TUESDAY...THEN HOVERING AROUND THOSE LEVELS
THROUGH THE DAY TUESDAY. DRY CONDITIONS ARE FORECAST WITH
TEMPERATURES CLOSE TO ECMWF PROGGED VALUES. PATTERN CHANGES COME
LATER TUESDAY AS A POTENT TROUGH DIGS DOWN INTO ALBERTA AND
SASKATCHEWAN. THIS TROUGH ALL MODELS HAVE DIGGING DOWN INTO THE
UPPER MIDWEST FOR WEDNESDAY AND THURSDAY...BUT AGAIN THE TIMING
VARIES. THE 06.00Z GFS/GFS ENSEMBLES/CANADIAN ALL BRING IT INTO THE
FORECAST AREA LATE WEDNESDAY...WHEREAS THE 05.12Z ECMWF STILL HAS IT
BACK OVER THE DAKOTAS AT THE SAME TIME. FOR NOW HAVE FOLLOWED A
CONSENSUS BLEND UNTIL THE TIMING CAN SORT ITSELF OUT. 850MB TEMPS
PLUMMET WITHIN THE TROUGH...DROPPING TO -12 TO PERHAPS AS COLD AS
-20C UNDER THE CORE OF IT. SO CERTAINLY MORE WINTER LIKE AIR WILL
END UP MOVING INTO THE FORECAST AREA. PRECIPITATION ON THE OTHER
HAND IS MUCH MORE UNCERTAIN...DUE TO MOST OF THE MOISTURE TRAPPED
WITH A SYSTEM TRACKING ALONG THE GULF COAST INTO THE MID-ATLANTIC
STATES. THERE IS SOME AGREEMENT ON A BAND OF DEFORMATION AND DPVA
FORCED PRECIPITATION AHEAD OF THE TROUGH...BUT UNCERTAINTIES ON
TIMING AND AVAILABLE MOISTURE RESULT IN NO HIGHER THAN 20-30 PERCENT
CHANCES AT THIS TIME.
&&
.AVIATION...TODAY AND TONIGHT
514 AM CST FRI JAN 6 2012
VFR CONDITIONS ARE EXPECTED AT THE TAF SITES THROUGH THE FORECAST
PERIOD. A TROUGH WILL MOVE ACROSS THE AREA TODAY WITH WINDS
SWITCHING TO THE NORTHWEST AT 10 TO 15 KTS WITH GUSTS TO AROUND 20
KTS POSSIBLE. THE MAIN IMPACTS FROM THE TROUGH WILL BE THE WIND
SWITCH AND SCT-BKN HIGH CLOUDS MOVING THROUGH. PLAN ON CLOUD BASES
IN THE 8 TO 15 KFT RANGE AS THE TROUGH MOVES ACROSS THE UPPER
MISSISSIPPI RIVER VALLEY. LOOK FOR MOSTLY CLEAR SKIES TO RETURN
TONIGHT. SOME MVFR CEILINGS WILL ADVECT SOUTHWARD FROM SOUTHERN
ONTARIO/MANITOBA TONIGHT INTO EARLY SATURDAY MORNING. MODELS KEEP
THE LOW LEVEL MOISTURE ACROSS NORTHERN WISCONSIN/MINNESOTA. WILL
HAVE TO MONITOR THE PROGRESSION OF THE STRATUS DECK CLOSELY LATE
TONIGHT INTO EARLY SATURDAY MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
215 AM CST FRI JAN 6 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
215 AM CST FRI JAN 6 2012
.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
215 AM CST FRI JAN 6 2012
MAIN FORECAST CONCERNS ARE CLOUDS AND TEMPERATURES IN THIS ABOVE
NORMAL TEMPERATURE PATTERN.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED WEAK RIDGING ALONG THE WEST COAST OF THE U.S. AND BRITISH
COLUMBIA...A SHORTWAVE TROUGH OVER MONTANA...THEN NEARLY ZONAL FLOW
FROM THE DAKOTAS EASTWARD INTO NEW ENGLAND. AHEAD OF THE SHORTWAVE
TROUGH...A 90-110 KT JET WAS PRESENT FROM THE DAKOTAS INTO UPPER
MICHIGAN. THIS JET COMBINED WITH A STREAM OF PACIFIC MOISTURE IS
HELPING TO PRODUCE SCATTERED-BROKEN CIRRUS FROM SOUTH DAKOTA AND
NEBRASKA NORTHEASTWARD ACROSS THE FORECAST AREA. MOISTURE VERY HARD
TO COME BY BELOW THIS CIRRUS...NOTED BY 10C OR HIGHER DEWPOINT
DEPRESSIONS FROM THE SURFACE TO 500MB ON 00Z SOUNDINGS FROM
MPX...ABR AND BIS. 850MB TEMPS ON THESE SOUNDINGS RANGED FROM AROUND
10C AT ABR AND MPX...WHILE A COOLER READING OF 7C WAS REPORTED AT
BIS. BIS WAS LOCATED BEHIND A COLD FRONT WHICH CURRENTLY EXTENDS
FROM DES MOINES IOWA INTO NORTHEAST WISCONSIN. 925MB VAD WIND PROFILER
DATA DEPICTS 30-40 KT NORTHWEST WINDS IN THE WAKE OF THE FRONT.
DESPITE THIS COLD ADVECTION...THE WINDS IN CONJUNCTION WITH THE
CLOUDS AND GENERALLY MILD AIRMASS BEHIND THE FRONT...HAS HELPED TO
KEEP TEMPERATURES UP IN THE 30S AND INTO THE LOW 40S.
TODAY AND TONIGHT...SHORTWAVE TROUGH OVER MONTANA IS FORECAST BY ALL
MODELS TO MOVE ACROSS THE FORECAST AREA TONIGHT...THOUGH THE CRUX OF
THE TROUGH LOOKS TO AFFECT UPPER MICHIGAN. AS THE TROUGH APPROACHES
THE AREA TODAY...THE UPPER JET STREAK SEEN AHEAD OF IT WILL SLOWLY
SINK TO THE SOUTHEAST...AND THEREFORE SO WILL THE SCATTERED-BROKEN
CIRRUS. ALONG WITH THE SLOW DECREASE IN CLOUDS FROM THE NORTHWEST TO
SOUTHEAST...THE APPROACH OF THE TROUGH ALONG WITH THE PASSAGE OF THE
CURRENT COLD FRONT MEANS COLD ADVECTION TODAY. STILL...THE COLD
ADVECTION IS GRADUAL...NOTED BY 925MB TEMPS WHICH START OFF AT 6-8C
AT 12Z AND ONLY FALL TO 1-4C BY 00Z. SUNSHINE THROUGH THE HIGH
CLOUDS...WINDS TO HELP WITH MIXING...MOSTLY A LACK OF SNOW EXCEPT
NORTH OF I-94...AND A WARM START OFF SHOULD YIELD ANOTHER WELL ABOVE
NORMAL DAY TODAY. MOST AREAS SHOULD AT LEAST SEE HIGHS IN THE 40S
WITH SOME LOCATIONS REACHING INTO THE LOWER 50S. A LITTLE COOLER AIR
COMES IN TONIGHT WITH 925MB TEMPS FALLING TO -2 TO -5C BY 12Z
SATURDAY. SOME LOW CLOUDS MAY ACCOMPANY THIS COOLING AND DROP DOWN
INTO NORTH CENTRAL WISCONSIN...BUT NO LIFT IS PRESENT WITHIN THE
CLOUD LAYER TO PRODUCE PRECIPITATION. GENERALLY FOLLOWED A BLEND OF
GUIDANCE FOR LOWS.
SATURDAY THROUGH SUNDAY NIGHT...SHORTWAVE TROUGH OVER THE AREA
TONIGHT IS PROGGED TO SCOOT OFF TO THE EAST ON SATURDAY...LEAVING
THE AREA IN WEAK BROAD TROUGHING. THERE ARE INDICATIONS OF ANOTHER
SHORTWAVE TROUGH COMING THROUGH THE AREA SUNDAY NIGHT...IN ADVANCE
OF RIDGING BUILDING UP ACROSS THE NORTHERN ROCKIES INTO SOUTHWEST
CANADA. NONE OF THESE FEATURES ARE EXPECTED TO PRODUCE ANY
PRECIPITATION...DUE TO THE PRESENCE OF TOO MUCH DRY AIR. THERE WILL
BE PERIODS OF CLOUDS AFFECTING THE AREA...HOWEVER. THE FIRST IS
ALONG AND NORTH OF I-94...WHERE LOW CLOUDS ARE POSSIBLE SATURDAY
INTO SATURDAY NIGHT. THESE CLOUDS ARE ASSOCIATED WITH THE LOW LEVEL
COOLING LEFT BEHIND FROM TONIGHTS SHORTWAVE TROUGH. ANTICIPATING
THESE CLOUDS TO CLEAR OUT ON SUNDAY AS WARM/DRY ADVECTION SURGES IN
FROM THE PLAINS. THIS SAME ADVECTION ON THE OTHER HAND DOES LOOK
TO PRODUCE SOME MID/HIGH CLOUDS...MAINLY SATURDAY NIGHT AND SUNDAY
ACROSS THE SOUTHERN 2/3 OF THE AREA. THESE CLOUDS SHOULD CLEAR OUT
SUNDAY NIGHT AS THE NEXT SHORTWAVE TROUGH MOVES THROUGH. REGARDING
TEMPERATURES...925MB READINGS ARE PROGGED TO HOLD FAIRLY STEADY
THROUGH SUNDAY MORNING...BETWEEN -2 AND -6C...THEN SLOWLY START
RISING TO AROUND 0C BY 12Z MONDAY AS THE NEXT SHORTWAVE TROUGH COMES
THROUGH. THIS MEANS THE WEEKEND WILL BE COOLER...BUT STILL ABOVE
NORMAL. A BLEND OF GUIDANCE WITH A LEAN TOWARDS THE ECMWF SEEMS
APPROPRIATE...SINCE THE ECMWF HAS BEEN DOING WELL IN THIS ABOVE
NORMAL PATTERN.
.LONG TERM...MONDAY THROUGH THURSDAY NIGHT
215 AM CST FRI JAN 6 2012
06.00Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES REMAIN IN GOOD AGREEMENT
WITH PREVIOUS RUNS AND WITH EACH OTHER ON THE UPCOMING WEATHER
PATTERN FOR NEXT WEEK. THERE ARE SOME TIMING DIFFERENCES FOR THE
MIDDLE OF THE WEEK...BUT IN GENERAL THEY DEPICT A WELL AGREED UPON
PATTERN. MONDAY AND TUESDAY FEATURE WELL ABOVE NORMAL WARMTH
AGAIN...IN RESPONSE TO THE BUILDING RIDGING OVER THE NORTHERN
ROCKIES ON SUNDAY NIGHT BEING FLATTENED AND SENT EASTWARD THROUGH
THE FORECAST AREA. 925MB TEMPS RESPOND BY JUMPING FROM THE 0C AT 12Z
MONDAY TO 2-4C AT 00Z TUESDAY...THEN HOVERING AROUND THOSE LEVELS
THROUGH THE DAY TUESDAY. DRY CONDITIONS ARE FORECAST WITH
TEMPERATURES CLOSE TO ECMWF PROGGED VALUES. PATTERN CHANGES COME
LATER TUESDAY AS A POTENT TROUGH DIGS DOWN INTO ALBERTA AND
SASKATCHEWAN. THIS TROUGH ALL MODELS HAVE DIGGING DOWN INTO THE
UPPER MIDWEST FOR WEDNESDAY AND THURSDAY...BUT AGAIN THE TIMING
VARIES. THE 06.00Z GFS/GFS ENSEMBLES/CANADIAN ALL BRING IT INTO THE
FORECAST AREA LATE WEDNESDAY...WHEREAS THE 05.12Z ECMWF STILL HAS IT
BACK OVER THE DAKOTAS AT THE SAME TIME. FOR NOW HAVE FOLLOWED A
CONSENSUS BLEND UNTIL THE TIMING CAN SORT ITSELF OUT. 850MB TEMPS
PLUMMET WITHIN THE TROUGH...DROPPING TO -12 TO PERHAPS AS COLD AS
-20C UNDER THE CORE OF IT. SO CERTAINLY MORE WINTER LIKE AIR WILL
END UP MOVING INTO THE FORECAST AREA. PRECIPITATION ON THE OTHER
HAND IS MUCH MORE UNCERTAIN...DUE TO MOST OF THE MOISTURE TRAPPED
WITH A SYSTEM TRACKING ALONG THE GULF COAST INTO THE MID-ATLANTIC
STATES. THERE IS SOME AGREEMENT ON A BAND OF DEFORMATION AND DPVA
FORCED PRECIPITATION AHEAD OF THE TROUGH...BUT UNCERTAINTIES ON
TIMING AND AVAILABLE MOISTURE RESULT IN NO HIGHER THAN 20-30 PERCENT
CHANCES AT THIS TIME.
&&
.AVIATION...
1110 PM CST THU JAN 5 2012
AN UPPER LEVEL SHORTWAVE TROUGH WAS MOVING TOWARD THE NORTHERN GREAT
LAKES LATE TONIGHT...BRINGING SOME HIGH THIN CLOUDS TO THE TAF
SITES...BUT NO PCPN WORRIES. A WEAK RIPPLE IN THE SFC PRESSURE
GRADIENT FIELD WAS ALSO APPROACHING...BUT MOST WINDS WERE ALREADY
WESTERLY. HOWEVER...MISSISSIPPI RIVER VALLEY LOCATIONS
DECOUPLED...AND THUS SOME VARIABLE BUT MOSTLY LIGHT SOUTH-SOUTHEAST
AT KLSE. EXPECT THESE WILL CONTINUE UNTIL AROUND 12Z...ALTHOUGH A
FEW HOURS LONGER INTO THE MORNING IS NOT OUT OF THE QUESTION. TRENDS
WILL BE MONITORED. WINDS WILL MIX A BIT DEEPER ON FRIDAY...LENDING A
BETTER POTENTIAL FOR SOME AFTERNOON GUSTINESS. OVERALL...VFR
CONDITIONS WILL PERSIST.
A POINT OF POTENTIAL INTEREST IS A BANK OF LOW/MVFR CLOUDS THE
MODELS WANT TO SLIDE SOUTH ACROSS NORTHERN WI FRI NIGHT. TRENDS
WOULD KEEP THIS NORTH OF THE TAFS SITES...AND WILL KEEP THEM THIS
WAY FOR NOW. BEARS WATCHING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
215 AM CST FRI JAN 6 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RIECK
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND JUNCTION CO
923 PM MST SAT JAN 7 2012
.UPDATE...
THE UPPER LEVEL TROUGH CONTINUES TO SAG SOUTH WITH SNOW WINDING
DOWN OVER ALL OF THE NORTHERN ZONES. STILL SOME AREAS OF
CONCENTRATED HEAVIER SNOW FALLING OVER THE CENTRAL MOUNTAINS AND
LIGHT SNOW LINGERING ALONG THE INTERSTATE 70 CORRIDOR FROM
GLENWOOD CANYON EAST TO AVON. SO WILL HANG ON TO THOSE ADVISORIES
FOR A FEW MORE HOURS...BUT REMAINDER OF HIGHLIGHTS HAVE BEEN
DROPPED.
&&
.AVIATION /FOR 06Z TAF ISSUANCE/...
SNOW SHOWERS WILL COME TO A GRADUAL END OVERNIGHT THROUGHOUT
WESTERN COLORADO AND EASTERN UTAH. LOW STRATUS DECKS EXPECTED IN
MANY OF THE LOWER VALLEYS BY EARLY SUNDAY MORNING...WITH PATCHY
FOG RESTRICTED VISIBILITIES AT TIMES. EXPECT AREAS OF MVFR AND IFR
CIGS AND VSBYS FROM 06Z THROUGH 15Z SUNDAY. VFR CONDITIONS ARE
THEN EXPECTED TO RETURN TO EASTERN UTAH AND WESTERN COLORADO BY
MIDDAY SUNDAY.
&&
.PREV DISCUSSION... /ISSUED 548 PM MST SAT JAN 7 2012/...
.UPDATE...
CONTINUING TO PULL BACK THE WINTER WEATHER HIGHLIGHTS BASED ON
LATEST SURFACE OBS AND SPOTTER REPORTS. HAVE NOW CANCELLED THE
NORTHWEST PLATEAU IN NORTHWEST COLORADO AS SNOW HAS ENDED AT CRAIG
AND MEEKER AND CEILINGS CONTINUE TO LIFT. RADAR RETURNS SUPPORT
HIGHLIGHTS OVER THE CENTRAL ZONES...JUST AHEAD OF THE UPPER LEVEL
TROUGH THAT IS SAGGING THROUGH THE FORECAST AREA...SO NO OTHER
ADJUSTMENTS PLANNED AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 448 PM MST SAT JAN 7 2012/...
.UPDATE...
SNOWFALL COMING TO A RAPID END ACROSS THE EASTERN UINTA MOUNTAINS
LATE THIS AFTERNOON BASED ON CURRENT WEB CAMS IN THE REGION. AS A
RESULT...HAVE DROPPED THE WINTER WEATHER ADVISORY FOR THIS AREA
AND ADJUSTED THE CHANCE OF PRECIPITATION FOR THE REMAINDER OF THIS
EVENING. BASED ON CURRENT TRACK AND SPEED OF THE UPPER LEVEL
LOW...ADDITIONAL ADJUSTMENTS MAY BE NEED TO CURRENT WINTER
HIGHLIGHTS. WILL CONTINUE TO MONITOR.
&&
.PREV DISCUSSION... /ISSUED 305 PM MST SAT JAN 7 2012/
.SHORT TERM /TONIGHT THROUGH MONDAY/...
LATEST MOSAIC IMAGERY SHOWING LARGE BAND OF SNOW MOVING ACROSS
BOOKCLIFFS THEN EASTWARD ALONG INTERSTATE 70 TOWARDS GLENWOOD
SPRINGS AND EAGLE. CDOT WEBCAMS ALSO SHOWING PLENTY OF SNOW ALONG
THE CORRIDOR. CROSS-SECTIONS INDICATE RATHER LARGE AREA OF
CONDITIONAL SYMMETRIC INSTABILITY MATCHING UP WITH THIS BAND WHICH
WOULD EXPLAIN THE RAPID SNOW ACCUMULATIONS AT THE SFC DUE TO SOME
SLANTWISE CONVECTION. IF THE BAND STAYS TOGETHER AND CONTINUES TO
DROP SWRD...SOME QUICK ACCUMULATIONS ARE POSSIBLE OVER GRASSY
SURFACES OVER GRAND VALLEY AND AREAS SOUTH. HAVING SAID THAT...MODELS
DO KEEP THIS BAND TO OUR NORTH WITH SOME SLOW SWRD DRIFT THROUGH
THE AFTN AND EVENING. NORTH OF THIS AREA...SNOW CONTINUES TO FALL
OVER AND NEAR CRAIG...HAYDEN AND MEEKER. HILITES APPEAR TO BE ON
TRACK WITH SOME CONCERN REMAINING FOR THE UNCOMPAHGRE PLATEAU AND
NRN SAN JUANS AS RUC AND HRRR SHOW SOME DEVELOPMENT OVER THAT
AREA. OF COURSE...18Z NAM SHOWS SOME PRECIP BUT NOT ENOUGH TO
WARRANT ANY ADVISORIES. WILL NOT PULL THE TRIGGER YET BUT WILL
KEEP AN EYE ON WEBCAMS...RADAR...SATELLITE AND LOCAL SNOW REPORTS.
SFC COLD FRONT MOVED THROUGH AREA QUICKER THAN EXPECTED AND IS
CLEARLY SEEN ON WATER VAPOR AND IR IMAGERY MOVING OVR SERN CO AND
NRN NM. THE UPPER LEVEL TROF AND UPPER LOW REMAIN OVER NERN UT
ATTM AND ARE STILL EXPECTED TO MOVE OVER THE REGION THIS AFTN INTO
TONIGHT CAUSING MORE SNOWFALL. THUS...MADE LITTLE TO NO CHANGE FOR
OVERNIGHT FORECAST. SINCE SPEED OF SYSTEM HAS INCREASED
SOMEWHAT...AGREE WITH PREVIOUS THINKING THAT HILITES MAY HAVE TO
BE TAKEN DOWN EARLY PROBABLY NEARER TO EARLY SUNDAY MORNING. WILL
LEAVE AS IS FOR NOW.
BY SUNDAY...MOSTLY SUNNY SKIES FOR AREAS N AND CLEARING SKIES FOR
THE SOUTH. TEMPS WILL RUN NEAR NORMAL FOR THIS TIME OF YEAR...OR
ABOUT 10 DEGREES COOLER THAN SEEN THIS PREVIOUS WEEK. HIGH
PRESSURE WILL BUILD IN AND PERSIST THROUGH MID-WEEK.
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/
EASTERN UTAH AND WESTERN COLORADO WILL BE UNDER THE INFLUENCE OF AN
UPPER RIDGE MONDAY NIGHT AND TUESDAY...SQUEEZED BETWEEN A WRAPPED UP
SOUTHERN PLAINS LOW AND THE NEXT TROF ARRIVING OUT OF THE NORTHEAST
PACIFIC. AS SUCH THE DRY WEATHER WILL CONTINUE OVER THIS PERIOD WITH
THE WARMING ALOFT HELPING TO ENFORCE THE LOW LEVEL
INVERSIONS...ESPECIALLY IN AREAS WITH THE NEWER SNOW COVER AND DID
DIRECT TEMPERATURES TOWARD THE LOWER END OF GUIDANCE. BEYOND THIS
PERIOD CONFIDENCE CONTINUES TO WANE WITH DIFFERING MED RANGE MODEL
SOLUTIONS RELATED TO PROGRESSION OF THE WESTERN TROF. THE
DIFFERENCES ARE MOSTLY CENTERED AROUND THE EVOLUTION OF AN UPPER LOW
OVER THE SOUTHWEST CORNER OF THE CONUS AS ENERGY IN THE TROF SPLITS.
THE OPERATIONAL GFS SOLUTION IS SLOWER TO ACHIEVE THIS SPLIT WHICH
CONFLICTS WITH SOME OF IT/S MEMBERS AND WITH A REFLECTION OF A LOW
OFF THE SOCAL COAST IN THE H5 MEAN SOLUTION. THIS SLOWER SOLUTION
WOULD BE A WETTER SOLUTION AND IMPACT MORE OF THE CWA. FOR NOW
FORECAST CONTINUES TO LEAN AWAY FROM THIS TOWARD THE EURO WITH A
MORE NORTHERLY FLOW DOMINATING TUESDAY NIGHT INTO WEDNESDAY AS A
CLIPPER TYPE SYSTEM DROPS THROUGH THE NORTHERN PLAINS. THIS WOULD
BRING SOME OROGRAPHICS AND WEAK DYNAMICS TO THE CENTRAL AND NORTHERN
MOUNTAINS FOR A SLIGHT CHANCE OF SNOW. BEHIND THIS REX BLOCK SETS UP
IN THE WEST WITH DRY AND ABOVE NORMAL TEMPERATURES RETURNING TO THE
CWA FOR THE LAST HALF OF THE WEEK.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL NOON MST SUNDAY FOR ZONES 008>010-
012.
UT...NONE.
&&
$$
UPDATE.......JDC
SHORT TERM...TGR
LONG TERM....15
AVIATION.....JDC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1220 AM EST SUN JAN 8 2012
UPDATED AVIATION DISCUSSION FOR 06Z TAFS
.SYNOPSIS...
WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL NRN STREAM
FLOW THROUGH THE UPPER GREAT LAKES. A WEAK SHORTWAVE THAT HAS HELPED
BOOST LES INTENSITY TODAY WAS EXITING TO THE EAST OF LAKE SUPERIOR.
OTHERWISE...NO SIGNIFICANT SHRTWVS WERE NOTED UPSTREAM THAT WOULD
IMPACT WEATHER THROUGH SUN. AT THE SFC...A TROUGH FRONT WAS NEARLY
STATIONARY ACROSS NRN UPPER MI. 850 MB TEMPS NEAR -14C PROVIDED JUST
ENOUGH INSTABILITY FOR LIGHT LES WITH LOW LEVEL NW FLOW.
&&
.SHORT TERM...TONIGHT AND SUNDAY
WEAKER AND INCREASINGLY ANTICYCLONIC FLOW WITH SFC RDG MOVING IN
FROM THE WEST WILL TEND TO BACK WINDS MORE WRLY LATE TONIGHT INTO
SUNDAY. THE MOST FAVORABLE LOW LEVEL CONV WOULD FOCUS LES OVER THE
KEWEENAW PENINSULA AND FROM MUNISING EASTWARD ALONG THE ERN
SHORELINE. MAINTAINED HIGH CHC TO LIKELY POPS FOR ADDITIONAL LES
ACCUMS OF AN INCH OR LESS OVER THE KEWEENAW PENINSULA AND ERN
ALGER...LUCE AND NRN SCHOOLCRAFT COUNTIES. EXPECT DRY CONDITIONS TO
THE SOUTH.
A BAND OF 275K-280K ISENTROPIC ASCENT AND 900-800 MB FGEN MOVING
INTO THE WEST LATE AND ACROSS THE CWA LATE TONIGHT AND SUN MORNING
COULD PRODUCE SOME LIGHT SNOW WITH MINIMAL ACCUMULATIONS OF A FEW
TENTHS. SO...ONLY SLIGHT CHANCE POPS WERE INCLUDED AWAY FROM LAKE
SUPERIOR. LOW LEVEL BACKING MORE WRLY BY SUNDAY ALONG WITH MARGINAL
LAKE INSTABILITY (850 MB TEMPS CLIMBING TO AROUND -12C) SUPPORT ONLY
LOW CHC POPS FOR LES OVER MAINLY THE KEWEENAW PENINSULA AND
SHORELINE AREAS EAST OF MUNISING. WITH THE LIGHT WIND FIELD
UNCERTAINTY REMAINS WHETHER ANY MESO LOW OR SHORELINE PARALLEL BAND
WILL DEVELOP...PER HIGH RES WRF/ARW.
.LONG TERM /00Z MON THROUGH NEXT SAT/...
STARTING MONDAY AT 00Z THERE WILL BE A BROAD 500MB TROUGH OVER ERN
CANADA/NERN CONUS...WITH A SHARP TROUGH BRANCHING OFF OF THAT FROM
OVER OUR CWA TO THE AZ/NM BORDER...AND A 500MB RIDGE W OF THAT
TROUGH. BY TUESDAY...THE AZ/NM TROUGH WILL CLOSE OFF AND MOVE TO
TX...BREAKING FREE OF THE ERN CANADA TROUGH AS IT MOVES E. ANOTHER
SYSTEM WILL PUSH INTO THE PACIFIC NW...WHICH WILL PUSH THE W COAST
RIDGE OVER THE CWA DURING THE DAY TUESDAY. MODELS HAVE HAD POOR RUN
TO RUN CONTINUITY WITH THE NEXT SYSTEM MOVING IN FOR THE MIDDLE OF
THE WEEK. MODELS BRING AN UPPER TROUGH OFF A CLOSED LOW OVER AK INTO
THE REGION...DEEPENING IT INTO A CLOSED LOW NEAR OR OVER THE CWA
WED. THE CLOSED LOW MOVES OFF TO THE NE THU NIGHT OR FRIDAY...WITH
AN UPPER TROUGH HANGING AROUND E OF THE CWA THROUGH SATURDAY.
FOR MON...A SHORTWAVE WILL MOVE THROUGH THE REGION...BUT THE BEST
DYNAMICS WILL BE FARTHER NE...SO ANY POPS WERE LIMITED TO LAKE
SUPERIO OR ERN UPPER MI. EVEN WITH CLOUD COVER FROM THIS
SYSTEM...HIGH WILL BE IN THE MID TO UPPER 30S WITH WAA FROM THE W
THROUGH THE DAY. 850MB TEMPS AT 00Z MON WILL BE AROUND
-9C...INCREASING TO AROUND 0C BY 00Z TUE.
MON NIGHT AND TUE...AS THE UPPER RIDGE MOVES OVERHEAD TUE...EXPECT
DRY CONDITIONS WITH FEWER CLOUDS...ESPECIALLY BEFORE EVENING.
THICKNESSES WILL BE SLIGHTLY INCREASED TUE...SO HIGHS WILL BE A
COUPLE DEGREES WARMER AROUND 40.
WED THROUGH FRI...AS NOTED PREVIOUSLY...MODELS SHOW INCREASED
DISAGREEMENT AND DECREASED RUN TO RUN CONTINUITY WITH A SYSTEM
EJECTING OUT OF AK. COMPARING THE 12Z/07 GFS...00Z/07 ECMWF...AND
12Z/07 GEM SOLUTIONS...THE GEM WAS RULED OUT SINCE IT SHOWS A FAR
DIFFERENT SCENARIO THAN THE OTHER TWO MODELS. BOTH THE GFS AND ECMWF
BRING A 500MB TROUGH FROM A CLOSED LOW OVER AK...SHOWING A LOW
CLOSING OFF FROM THE TIP OF THE TROUGH AS IT MOVES SE. MODELS THEN
DEPICT THE TROUGH MOVING TOWARD THE CWA BEFORE DEEPENING JUST
UPSTREAM OF THE CWA IN RESPONSE TO JET INTERACTION. THE GFS CLOSES
THE UPPER LOW OFF AS IT MOVES ACROSS THE CENTRAL MANITOBA/ONTARIO
BORDER AROUND 18Z WED...AND MARCHES IT JUST N OF LAKE SUPERIOR
BEFORE MOVING INTO QUEBEC AROUND 06Z FRI. THE STRONGER ECMWF CLOSES
THE LOW OFF OVER THE ND/MANITOBA BORDER AROUND 12Z WED...THEN
CONTINUES TO DEEPEN THE SYSTEM AS IT MOVES TO THE IL/WI BORDER BY
12Z THU...THEN TO THE LOWER GREAT LAKES BY 12Z FRI. SET THE CLOCK
BACK A BIT TO FIND WHERE MODELS START TO DIVERGE WITH THIS SYSTEM.
BACK WHEN THE TROUGH IS MOVING OVER WRN CANADA...THE SLIGHTLY
STRONGER ECMWF IS MUCH FASTER TO CLOSE OFF THAT LOW...WHICH THEN
MOVES S AND STAYS WELL OFF THE CA COAST THROUGH THE EVENT. THE
GFS...ON THE OTHER HAND...CLOSES THE LOW OFF OVER SRN CA...WHICH
LEADS TO THAT LOW MOVING INTO AZ AND NM THROUGH THE EVENT. HAVING
THAT LOW IN PLACE THE GFS PUTS IT CUTS OFF SOME ACCESS TO COMPONENTS
OF BOTH THE NRN AND SRN STREAM JETS...WHICH IS WHY THE SYSTEM DOES
NOT STRENGTHEN AS MUCH AND STAYS FARTHER N WITH THE GFS SOLUTION.
REGARDLESS OF SOLUTION...BOTH MODELS BRING 850MB TEMPS AS LOW AS
-20C OVER LAKE SUPERIOR WITH THE SYSTEM. THE GFS HAS NW BL
WINDS...WHILE THE ECMWF HAS MORE NORTHERLY WINDS SINCE THE SFC LOW
WILL BE MORE TO OUR E. AT THIS POINT...I FEEL COMFORTABLE WITH
LIKELY POPS SINCE CONFIDENCE THAT IT WILL SNOW IS MUCH HIGHER THAN
THE CONFIDENCE OF WHERE THE MOST SNOW WILL FALL. IF THE ECMWF IS
CORRECT...WE COULD BE LOOKING AT VERY SIGNIFICANT SNOWFALL
AMOUNTS...ESPECIALLY IN NORTH WIND SNOWBELTS. THE GFS SOLUTION WOULD
LEAD TO MUCH LOWER SNOWFALL TOTALS THAN THE ECMWF...SINCE THE ECMWF
ALSO CONTRIBUTES A SIGNIFICANT AMOUNT OF SYNOPTIC PRECIP.
&&
.AVIATION /FOR THE 06Z TAF ISSUANCE/...
EXPECT PERIODIC LIGHT LK EFFECT SNOW SHOWERS AT KCMX THROUGH TONIGHT
INTO EARLY SUNDAY MORNING. CIGS SHOULD DROP TO MVFR AT ALL SITES
LATE TONIGHT AS A WEAK SYSTEM MOVES THROUGH AND BRINGS IN SOME LOW
LEVEL MOISTURE. EXPECT IMPROVING CONDITIONS AT ALL SITES BY
AFTERNOON WITH DRIER AIR COMING IN AS CONDITIONS WILL GO TO VFR AND
STAY THERE THROUGH THE REST OF THE TAF PERIOD.
&&
.MARINE /FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE/...
LOW PRESSURE IS FORECAST TO SLIDE ACROSS ONTARIO THROUGH MONDAY.
STRONG PRESSURE FALLS NORTH OF LAKE SUPERIOR AND AN INCREASING
PRESSURE GRADIENT IS EXPECTED TO RESULT IN GALE FORCE SOUTHWESTERLY
WINDS OVER MUCH OF LAKE SUPERIOR ON MONDAY. A GALE WATCH REMAIN IN
EFFECT FOR THIS TIME FRAME. WINDS SETTLE DOWN BY TUESDAY WITH
WEAKENING PRESSURE GRADIENT...BUT INCREASE WEDNESDAY INTO THURSDAY
AS LOW PRESSURE SYSTEM/STRONG COLD FRONT PUSH ACROSS THE UPPER GREAT
LAKES REGION. EXACT WIND DIRECTION/SPEEDS ARE UNCERTAIN FOR
WEDNESDAY...BUT EVENTUALLY N/NW WINDS SHOULD REACH GALE OR NEAR GALE
FORCE BY THURSDAY IN WAKE OF THE LOW PRESSURE/COLD FRONT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM LATE SUNDAY NIGHT THROUGH MONDAY AFTERNOON FOR
LSZ162-263>266.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1140 PM CST SAT JAN 7 2012
.AVIATION...
VFR SHOULD PREVAIL THROUGH THE OVERNIGHT HOURS. LIFR CIGS HAVE
DEVELOPED NORTHEAST OF THE METROPLEX...AND THERE IS STILL LITTLE
CONFIDENCE ON WHETHER THESE CIGS WILL REMAIN NORTHEAST OF THE TAF
SITES OR MOVE INTO THE AREA AROUND SUNRISE. HRRR REMAINS
PESSIMISTIC WHILE THE RUC LIFTS THEM NORTH. WILL STILL MAINTAIN A
MENTION OF BKN020 IN THE TAFS FOR TOMORROW MORNING TO ACCOUNT FOR
THE POSSIBILITY THAT THESE CLOUDS OR SOME OF THIS LOW LEVEL
MOISTURE MAY SPILL INTO THE METRO TAF SITES. IF CIGS DO MAKE IT
INTO THE METROPLEX...MVFR WOULD LIKELY PREVAIL ALL DAY.
THE MORE CERTAIN PART OF THE FORECAST COMES TOMORROW EVENING WHEN
INCREASING LIFT AHEAD OF THE NEXT SYSTEM SHOULD RESULT IN MVFR
PREVAILING AFTER 0Z. CIG SHOULD LOWER SUNDAY EVENING TO IFR BY 6Z
MONDAY. SHOWERS WILL BEGIN TO DEVELOP IN THE EVENING AND INCREASE
IN COVERAGE. WILL CARRY LIGHT RAIN FOR THE 24-30HR PERIOD OF THE
DFW TAF.
IT IS AN EASIER FORECAST FOR WACO. VFR WILL PREVAIL BUT VFR CIGS
NEAR 3500FT WILL DEVELOP TONIGHT AND CONTINUE THROUGH TOMORROW.
CIGS WILL LOWER SUNDAY EVENING TO MVFR...WITH SOME SHOWERS IN THE
VICINITY.
TR.92
&&
.UPDATE...
SURFACE FRONT HAS COMPLETELY PUSHED THROUGH THE EASTERN COUNTIES
OF THE CWA NOW WITH LIGHT WINDS LESS THAN 5 MPH ACROSS MOST OF THE
REGION. SURFACE WINDS WILL REMAIN LIGHT OVERNIGHT BUT START TO
INCREASE FROM THE NORTH BY DAYBREAK AS ANOTHER SURFACE HIGH MOVES
ACROSS THE PLAINS. SURFACE DEWPOINTS ARE NOT EXPECTED TO CHANGE
MUCH OVERNIGHT THUS KEEPING WARMER OVERNIGHT LOWS IN THE 40S
ACROSS THE EASTERN COUNTIES WHILE THE WESTERN COUNTIES COOL INTO
THE 30S AGAIN. DENSE HIGH CLOUD COVER IS OVERSPREADING THE REGION
FROM THE SOUTHWEST...AHEAD OF THE UPPER LEVEL TROUGH NOW DIGGING
INTO ARIZONA. DESPITE THE LIGHT WINDS...THINK THE DENSE CLOUD
COVER WILL PREVENT FOG FROM DEVELOPING OVER THE EASTERN HALF OF
THE REGION /WHERE HIGHER DEWPOINTS WILL REMAIN/ AND HAVE REMOVED
THE MENTION OF THE FOG FROM THE FORECAST. LOW CLOUD COVER WILL
LIKELY CONTINUE TO PERSIST OVER THE NORTHEASTERN AND NORTHERN
COUNTIES OF NORTH TEXAS. ALSO FOR THE UPDATE...DID ADJUST
OVERNIGHT LOWS IN SEVERAL LOCATIONS BASED ON THE LATEST
TEMPERATURE TRENDS AND CHANGES TO THE DEWPOINTS DURING THE
OVERNIGHT PERIOD.
82/JLD
&&
.PREV DISCUSSION... /ISSUED 321 PM CST SAT JAN 7 2012/
THE WEAK COLD FRONT HAS SLOWED DRAMATICALLY ACROSS EAST TEXAS AND
OUR THE SOUTHEAST COUNTIES TODAY WITH MINIMAL PRESSURE RISES BEHIND
THE FRONT. A WEAK INVERTED TROUGH IN THE 925-850MB LAYER HAS BEEN
NEARLY STATIONARY AS WELL OVER THE I-35 CORRIDOR/RED RIVER VALLEY
ALL DAY. THIS HAS RESULTED IN WEAK ISENTROPIC ASCENT THAT IS
HOLDING STRATUS OVER NORTHERN COUNTIES AND MAKING THE FORECAST
DIFFICULT WITH REGARD TO CLOUD COVER AND TEMPERATURES. MEANWHILE
AN UPPER DISTURBANCE CONTINUES TO INTENSIFY AND DEEPEN OVER THE
CENTRAL ROCKIES.
THE HRRR/WRF AND RUC BAK40 SOUNDINGS ALL INDICATE AT LEAST SOME
POTENTIAL FOR FOG DEVELOPING OVERNIGHT WITH WINDS BECOMING LIGHT
AND A TIGHT MOISTURE GRADIENT UP THROUGH THE BOUNDARY LAYER
THROUGH MIDDAY SUNDAY. WE ARE INSERTING PATCHY FOG EAST OF A
BOWIE...MINERAL WELLS...KILLEEN LINE WITH MORE COVERAGE OF LIGHT
FOG ACROSS THE NORTHEAST COUNTIES. TOO DIFFICULT TO ASCERTAIN IF
ANY FOG WILL BE DENSE AT THIS TIME. ANY FOG SHOULD DISSIPATE BY
AFTERNOON AS NORTH WINDS MIX TO AROUND 10 MPH OR SLIGHTLY HIGHER
THOUGH SOUTHEAST COUNTIES WILL HAVE LIGHTER NORTHEAST WINDS.
ISENTROPIC LIFT BEGINS OVER THE STALLED FRONTAL BOUNDARY SUNDAY
AFTERNOON IN DEVELOPING WAA REGIME ACROSS OUR SOUTHEAST COUNTIES.
THE ROCKIES DISTURBANCE WILL DEEPEN AND CLOSE OFF OVER AZ/NM AS
WELL. LIGHT RAIN SHOULD SLOWLY DEVELOP ACROSS THE SOUTHEAST BY
AFTERNOON...THEN OVERSPREAD NORTH TEXAS SUNDAY NIGHT AND MONDAY
AS ISENTROPIC ASCENT INCREASES WITH PLENTY OF FETCH FROM THE GULF
OF MEXICO. A GOOD STEADY RAIN IS EXPECTED INTO MONDAY EVENING.
1-2 INCHES OF BENEFICIAL RAINFALL WILL LIKELY OCCUR OVER THE FULL
DURATION WITH ISOLATED AMOUNTS IN EXCESS OF 3 INCHES POSSIBLE
ACROSS FAR SOUTHEASTERN AREAS. HAVE MAINTAINED ISOLATED/EMBEDDED
THUNDERSTORMS WITH LARGE-SCALE LIFT INTENSIFYING AND LAPSE RATES
ALOFT INCREASING TO NEAR 7 DEG/C.
THE UPPER LOW SLIDES OVER WEST TX BY MONDAY EVENING...THEN MODELS
CONTINUE TO DIVERGE ON ACTUAL STRENGTH/TRACK MONDAY NIGHT AND TUESDAY.
WILL USE A MEAN OF THE TRACKS WITH COLDEST AIR ALOFT TRACKING
ACROSS AREAS JUST NORTHWEST OF THE DFW METROPLEX. WITH THIS IN
MIND...A RAIN/SNOW SHOWER MIX COULD OCCUR WITH DYNAMIC COOLING AND
COLDER SURFACE TEMPERATURES ACROSS THE HIGHER TERRAIN OF THE
WESTERN COUNTIES. BOTH SURFACE AND GROUND TEMPERATURES WILL
REMAIN WELL ABOVE FREEZING BUT PROFILES ALOFT MAY SUPPORT SOME
SNOW MIXING IN WITH THE RAIN. IF ANY MINOR ACCUMULATIONS WERE TO
OCCUR...IT WOULD BE MINOR AND BRIEF ON ELEVATED SURFACES OR
GRASSY AREAS. DETAILS REMAIN FUZZY WE DO NOT EXPECT A MAJOR
WINTER EVENT WITH THIS SYSTEM. A DRY NOSE DOES APPEAR TO ARRIVE
TUESDAY FROM THE SOUTHWEST AND GET INGESTED INTO THE SYSTEM WITH
PRECIPITATION CHANCES LOWERING QUICKLY FROM SOUTH TO NORTH AS THE
UPPER LOW LIFTS TOWARD THE OZARKS AND MISSISSIPPI VALLEY BY
TUESDAY NIGHT.
A STRONGER COLD FRONT TAPPING AIR FROM ALASKA AND WESTERN CANADA
ARRIVES THURSDAY/FRIDAY A STEEP UPPER RIDGE ACROSS THE WESTERN
STATES AND A DEEP TROUGH OVER THE GREAT LAKES AND MISSISSIPPI
VALLEY. MEANWHILE...THE GFS AND ECMWF AS SWAPPED SOLUTIONS
REGARDING A POSSIBLE SOUTHERN PIECE OF ENERGY MOVING ACROSS RIGHT
AROUND THAT TIME FRAME. FOR NOW...WE ARE MAINTAINING A DRY...BRISK
AND COLD FORECAST AND UNDERCUTTING MOS TEMPERATURES BY A GOOD 5
DEGREES OR MORE PER PATTERN RECOGNITION. IT IS POSSIBLE THAT HIGHS
MAY NEED TO BE LOWERED IN UPCOMING FORECASTS IF IT BECOMES EVIDENT
THAT THIS IS TRUE ARCTIC AIR ORIGIN.
WE WILL CONTINUE TO FINE TUNE THE LATE WEEK FORECAST ONCE WE GET
PAST OUR FIRST SYSTEM FOR THE EARLY PART OF THE WEEK.
05/
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 43 57 44 46 40 / 0 10 80 100 70
WACO, TX 41 63 46 49 39 / 0 20 90 100 50
PARIS, TX 46 56 43 51 40 / 5 20 70 100 90
DENTON, TX 41 55 39 44 38 / 5 10 70 90 80
MCKINNEY, TX 42 57 41 47 39 / 5 10 70 100 80
DALLAS, TX 44 58 45 47 41 / 0 10 80 100 70
TERRELL, TX 43 58 46 50 40 / 5 20 80 100 80
CORSICANA, TX 44 61 48 53 41 / 5 20 90 100 70
TEMPLE, TX 40 65 46 49 39 / 0 20 90 100 40
MINERAL WELLS, TX 36 57 37 42 36 / 0 10 70 90 60
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
215 AM CST SUN JAN 8 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
215 AM CST SUN JAN 8 2012
MAIN FORECAST CONCERN IS HIGH TEMPERATURES MONDAY AND TUESDAY
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED RIDGING ALONG THE WEST COAST OF THE U.S. INTO SOUTHERN
ALBERTA...AN UPPER LOW OVER ARIZONA...A SHORTWAVE TROUGH OVER
EASTERN MONTANA AND BROAD TROUGHING OVER SOUTHEAST CANADA. LACK OF
ANY SIGNIFICANT FEATURES NEAR THE FORECAST AREA RESULTING IN DRY
CONDITIONS ALONG WITH CLEAR SKIES. WITH A SURFACE HIGH PRESSURE
RIDGE IN PLACE AND A DRY ATMOSPHERE SEEN ON THE 00Z DVN AND MPX
SOUNDINGS...TEMPERATURES HAVE FALLEN INTO THE TEENS AND
20S...COLDEST IN THE TYPICAL COLD SPOTS IN WISCONSIN. UPSTREAM...
THERE IS AN AREA OF MID CLOUDS CROSSING THE DAKOTAS AHEAD OF
MONTANA SHORTWAVE TROUGH. 850MB TEMPS ACROSS THE NORTHERN
PLAINS/UPPER MIDWEST HAVE HELD FAIRLY STEADY THE PAST 12
HOURS...AROUND -4C AT BIS...ABR AND MPX FOR THEIR 12Z SOUNDINGS
YESTERDAY AND 00Z SOUNDINGS TODAY.
TODAY AND TONIGHT...SHORTWAVE TROUGH SEEN OVER EASTERN MONTANA IS
PROGGED TO DIG SOUTH INTO THE CENTRAL PLAINS...IN RESPONSE TO THE
UPPER RIDGING OVER THE WESTERN U.S. BUILDING NORTHEAST TOWARDS THE
NORTHERN PLAINS. THE AREA OF MID CLOUDS AHEAD OF THIS SHORTWAVE
THROUGH APPEAR TO SCATTER OUT/DISSIPATE AS THEY COME INTO THE
FORECAST AREA THIS AFTERNOON...LIKELY DUE TO THE SHORTWAVE DIGGING
SOUTH VERSUS EAST. THEREFORE...ANTICIPATING A MOSTLY SUNNY DAY
TODAY. WITH 925MB TEMPS EXPECTED AROUND -2C AT 18Z...HIGHS SHOULD
END UP A FEW DEGREES WARMER THAN YESTERDAY. FOR TONIGHT...MODELS
ALSO PROG A SHORTWAVE TO RIDE ON TOP OF THE BUILDING RIDGING INTO
THE NORTHERN PLAINS...FORECAST TO DROP DOWN INTO NORTHWEST WISCONSIN
AT 12Z MONDAY. THIS SHORTWAVE SHOULD HAVE A WARM FRONT ASSOCIATED
WITH IT...CROSSING THE FORECAST AREA VERY LATE TONIGHT. THIS
FRONT...IN CONJUNCTION WITH A TIGHTENING PRESSURE GRADIENT...SHOULD
HELP TO AT LEAST STABILIZE THE TEMPERATURE FALL AND POSSIBLY START
BRINGING TEMPERATURES UP AROUND 12Z. WITH CLEAR/MOSTLY CLEAR SKIES
IN THE EVENING...LOWS SHOULD FALL INTO THE 20S. NOT ANTICIPATING
MUCH MORE THAN SOME MID/HIGH CLOUD TO ACCOMPANY THE WARM FRONT...SO
NO PRECIPITATION IS FORECAST.
MONDAY THROUGH TUESDAY NIGHT...THE UPPER RIDGING THAT WAS BUILDING
TOWARDS THE NORTHERN PLAINS TONIGHT IS PROGGED TO FLATTEN OUT AND
PUSH EAST...MOVING INTO THE FORECAST AREA FOR TUESDAY. THE FEATURE
RESPONSIBLE FOR THIS IS A POTENT SHORTWAVE TROUGH...EXPECTED TO DROP
DOWN THROUGH ALBERTA ON TUESDAY...THEN DIG INTO EASTERN MONTANA AND
THE WESTERN DAKOTAS BY 12Z WEDNESDAY. FOR OUR AREA...THE MAIN
CONCERN IS TEMPERATURES...WITH THE UPPER RIDGING BRINGING WITH IT A
SURGE OF PACIFIC AIR MODIFIED BY DOWNSLOPING OFF THE ROCKIES. 925MB
TEMPS CLIMB TO 0-2C FOR 18Z MONDAY AND 2-6C FOR 18Z TUESDAY. COOLEST
READINGS ARE NORTH OF I-94. THIS CLIMB IN TEMPERATURES IS
ACCOMPANIED BY WHAT SHOULD BE BREEZY WEST TO SOUTHWEST WINDS...NOTED
BY 925MB WINDS STAYING UP BETWEEN 20-35KT FOR THE ENTIRE TIME
PERIOD. AMOUNT OF SUNSHINE WILL BE CRITICAL IN DETERMINING HOW WARM
WE GET...GIVEN THE LACK OF SNOW COVER. LOOKS TO BE SOME MID/HIGH
CLOUDS AROUND MONDAY MORNING...BUT THESE SHOULD SCATTER/CLEAR OUT IN
THE AFTERNOON AS THE UPPER RIDGE FLATTENS. ANOTHER WAVE OF MID/HIGH
CLOUDS LOOKS TO COME THROUGH MONDAY NIGHT INTO TUESDAY MORNING...BUT
AGAIN CLEARING OUT FOR THE AFTERNOON. THEREFORE...PLENTY OF
SUN IS ANTICIPATED...ESPECIALLY TUESDAY FOR WARMING. PREVIOUS
FORECAST HIGHS FOR BOTH MONDAY AND TUESDAY LOOK VERY
REASONABLE...STAYING ON THE HIGH END OF GUIDANCE WHICH HAS WORKED
FOR THE RECENT ABOVE NORMAL STRETCH. POTENTIAL DEFINITELY EXISTS
TO BREAK SOME RECORD HIGHS. LOWS MONDAY NIGHT LIKELY TO STAY WELL
ABOVE NORMAL TOO...ESPECIALLY OVER HIGHER TERRAIN AREAS. FOR
TUESDAY NIGHT...A COLD FRONT WELL AHEAD OF THE POTENT UPPER TROUGH
LOOKS TO MOVE THROUGH THE AREA BETWEEN 06-12Z. SKIES SHOULD STAY
MOSTLY CLEAR...BUT COLD ADVECTION REALLY DOESNT GET GOING UNTIL
AFTER 12Z. THEREFORE HAVE STAYED ON THE WARM SIDE OF
GUIDANCE...ESPECIALLY GIVEN THE WARM TUESDAY.
.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT
215 AM CST SUN JAN 8 2012
MAIN FORECAST CONCERN AND UNCERTAINTY FOR THE LONG TERM FORECAST
CONTINUES TO REVOLVE AROUND THAT POTENT TROUGH APPROACHING THE
NORTHERN PLAINS 12Z WEDNESDAY. 08.00Z ECMWF/GFS/CANADIAN ALL SHOW
THE TROUGH DIGGING INTO THE NORTHERN PLAINS ON WEDNESDAY THEN
PUSHING EAST...BUT THE EXTENT OF THE DIGGING AND THE TIMING OF HOW
FAST IT MOVES EAST ARE BOTH IN QUESTION. THE ECMWF AND TO SOME
DEGREE THE CANADIAN ARE BY FAR THE DEEPEST...AND BOTH PRODUCE A
TROWAL AREA OF PRECIPITATION THAT CROSSES THE FORECAST AREA MOSTLY
WEDNESDAY NIGHT. THE GFS...BEING LESS AMPLIFIED AND MORE
PROGRESSIVE...KEEPS ANY TROWAL AREA OF PRECIPITATION NORTH OF THE
AREA. ALL SOLUTIONS AGREE ON PRETTY DRAMATIC COOLING...WITH 850MB
TEMPS DROPPING FROM 4-6C AT 12Z WEDNESDAY TO -12 TO -16C BY 12Z
THURSDAY AND POTENTIALLY NEAR -20C BY 00Z FRIDAY. FOR NOW...TO
HANDLE THE UNCERTAINTIES FOR WEDNESDAY THROUGH THURSDAY...HAVE
STAYED WITH THE CONSENSUS APPROACH FOR BOTH PRECIPITATION CHANCES
AND TEMPERATURES. ONE DISTINCT CHANGE IS THAT WEDNESDAY ENDS UP
WARMER...DUE TO THE COOLING WHICH HAS TRENDED SLOWER. WOULD NOT BE
SURPRISED IF WEDNESDAY MAY HAVE TO BE WARMED EVEN MORE.
THE PERIOD FOR THURSDAY NIGHT THROUGH SATURDAY NIGHT DOES NOT GET
ANY EASIER TO FORECAST...AGAIN RELATED TO HOW FAST THE POTENT TROUGH
CAN EXIT TO THE NORTHEAST. ONE THING FOR CERTAIN IS THAT THERE IS A
STRONG CONSENSUS FOR RIDGING TO BUILD OVER THE WESTERN U.S. INTO
SOUTHWEST CANADA DURING THIS TIME. HOW MUCH OF THIS SPREADS EAST
INTO THE FORECAST AREA IS UNKNOWN. THE 08.00Z GFS TRIES TO SPREAD
SOME RIDGING INTO THE FORECAST AREA LATE SATURDAY...BUT THE ECMWF
AND GFS ENSEMBLES WOULD PREFER TROUGHING TO STAY LOCKED IN PLACE.
THINK THE LATTER SCENARIO IS MORE LIKELY. THIS MEANS ONLY A SLOW
MODERATION IN TEMPERATURES. POTENTIAL WOULD EXIST FOR SOME
PRECIPITATION CHANCES WITH SHORTWAVES RIDING THROUGH THE NORTHWEST
FLOW ALOFT...AS INDICATED BY THE NEW 08.00Z ECMWF FOR SATURDAY.
HOWEVER...TIMING SOMETHING THAT FAR OUT IN THE FORECAST AND GIVEN
THE UNCERTAINTIES IN THE UPPER PATTERN...HAVE LEFT THE THURSDAY
NIGHT THROUGH SATURDAY NIGHT TIME PERIOD DRY.
&&
.AVIATION...
1100 PM CST SAT JAN 7 2012
A WEAK SFC HIGH WILL MOVE EAST ACROSS THE REGION ON SUNDAY. LOOK FOR
A MOSTLY LIGHT WIND FIELD FROM THE SOUTHWEST. SOME HIGH THIN CLOUDS
COULD SPILL ACROSS THE TAF SITES...ASSOCIATED WITH UPPER LEVEL
DISTURBANCES MOVING WEST-EAST ACROSS IA/IL AND THE NORTHERN
PLAINS...BUT VFR CONDITIONS ARE EXPECTED.
THE SFC PRESSURE GRADIENT WILL START TO TIGHTEN SUNDAY NIGHT...
PERSISTING THROUGH MONDAY. LOOK FOR INCREASING WINDS IN THIS PERIOD
AS A RESULT...STAYING FROM THE SOUTHWEST.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
215 AM CST SUN JAN 8 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION..... RIECK
AREA FORECAST DISCUSSION...CORRECTED
NWS CARIBOU ME
550 AM EST SUN JAN 8 2012
.SYNOPSIS...
HIGH PRESSURE WILL BUILD ACROSS THE AREA TODAY THROUGH MONDAY.
ANOTHER LOW PRESSURE FROM CENTRAL CANADA WILL MOVE WELL NORTH OF
THE STATE ON TUESDAY. ANOTHER HIGH PRESSURE SYSTEM FROM NORTHERN
CANADA WILL BRIEFLY RIDGE ACROSS THE REGION ON WEDNESDAY BEHIND
A COLD FRONT LATE TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...AN EAST-WEST COLD FRONT CURRENTLY BISECTS THE FORECAST
AREA WHICH WILL CONTINUE TO SLOWLY SINK SOUTH TODAY. HAVE NOTED A THIN
STREAMER OF SNOW ACROSS NORTHERN SOMERSET AND PISCATAQUIS COUNTIES
EARLY THIS MORNING JUST ON THE NORTH SIDE OF THIS BOUNDARY. THIS
SHOULD GRADUALLY WEAKEN AND BE REPLACED BY ANOTHER STRONGER BAND A
BIT FURTHER NORTH AS WESTERLY WINDS BECOME MORE NORTHWEST. HAVE
UPDATED THE FORECAST TO ACCOUNT FOR THIS ACTIVITY...BUT NO OTHER
MAJOR CHANGES NEEDED.
PREVIOUS DISCUSSION...HIGH PRESSURE OVER THE GREAT LAKES WILL SLOWLY BUILD
EASTWARD TOWARD MAINE TODAY. A COLD FRONT THAT IS CURRENTLY DRAPED
ACROSS NORTHERN MAINE WILL SLIDE SOUTH THROUGH THE REMAINDER OF
THE AREA BY THIS AFTERNOON. SKIES HAVE CLEARED OVER THE SOUTHERN
THIRD OF THE FORECAST AREA WHILE NORTHERN AREAS REMAIN MOSTLY
CLOUDY BEHIND THE FRONT. COLDER AIR WILL SPILL INTO THE FORECAST
AREA THROUGH THE DAY AS NORTH FLOW PUSHES THE FRONT SOUTHWARD. THE
12KM NAM...3KM HRRR AND THE REGIONAL CANADIAN ALL INDICATE THAT A
NW-SE ORIENTED SNOW BAND WILL DEVELOP ACROSS THE FORECAST AREA
THIS MORNING...A RESULT OF THE COLDER AIR ALOFT MOVING OVER THE
RELATIVELY WARM WATERS OF THE SAINT LAWRENCE. THE BAND SHOULD SET
UP BY MID MORNING BUT WILL GRADUALLY DISSIPATE THIS AFTERNOON AS
THE FLOW LESSENS AS THE HIGH DRAWS NEAR. THE STEADIEST SNOW LOOKS
TO SET UP ACROSS THE NORTHERN MAINE WOODS AND EXTEND SOUTHEAST
TOWARD PATTEN AND KINGMAN WITH SNOWFALL AMOUNTS AROUND A HALF
INCH. ON EITHER SIDE AND DOWNWIND OF THIS BAND THERE`S JUST A
SLIGHT CHANCE OF SNOW SHOWERS SO LITTLE TO NO ACCUMULATION IS
EXPECTED IN THESE AREAS. AWAY FROM THE SNOWY AREAS...SKIES WILL BE
PARTLY TO MOSTLY SUNNY THROUGH THE DAY. THE SNOW SHOWERS WILL WANE
AND CLOUDS LESSEN LATE THIS AFTERNOON...WITH ALL AREAS MOSTLY
CLEAR BY THIS EVENING.
THE HIGH WILL BUILD OVER THE REGION OVERNIGHT TONIGHT...CRESTING
EARLY TOMORROW MORNING. CLEAR SKIES AND LIGHT WINDS WILL ALLOW FOR
GOOD RADIATIONAL COOLING. THEREFORE EXPECT A CHILLY NIGHT TONIGHT.
NORTHERN AREAS WILL BOTTOM OUT IN THE SINGLE DIGITS BELOW ZERO WHILE
THE USUAL COLD SPOTS IN NORTHWEST MAINE WILL DIP TO 10 TO 15 BELOW.
FURTHER SOUTH...CENTRAL AND SOUTHERN MAINE CAN EXPECT LOWS IN THE
SINGLE DIGITS ABOVE ZERO.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
SFC HI PRES WILL CROSS THE FA ON MON WITH PATCHY MID CLDNSS AS A
WEAK UPPER TROF MOVES EAST INTO THE MARITIMES. RETURN SW FLOW SETS
UP LATE IN THE DAY BEHIND THE HI AS MID CLDNSS INCREASES FROM THE
W IN THE EVE. A S/WV MOVG EWRD WILL THEN BRING SN SHWRS TO MSLY
NRN PTNS OF THE FA LATE MON NGT INTO TUE AS SFC LOW PRES TRACK
WELL N OF THE FA. UNLIKE THIS PAST EVENT...WHERE A STRONG W-E QUASI-
STATIONARY FRONTAL BOUNDARY WAS IN PLACE JUST S OF OUR FA TO
ENHANCE THE OVRRNG SNFL OVR SPCLY NRN PTNS OF THE FA...THIS S/WV
WILL NOT HAVE THIS TYPE OF BOUNDARY...SO SNFL IS ANTICIPATED TO
BE MUCH LIGHTER...WITH ARND AN INCH OVR FAR NRN PTNS OF THE FA
LATE MON NGT THRU TUE AND LESSER AMOUNTS PROGRESSIVELY FURTHER S.
A MDT SFC COLD FRONT BEHIND THE S/WV CROSSING THE FA LATE TUE AFTN
INTO EVE WILL BRING THE S FRINGE OF ARCTIC AIR BACK INTO SPCLY NRN
PTNS OF THE FA BY LATE TUE NGT INTO MORN WITH A BRISK EVENING WIND
SLACKENING BY WED MORN. CLDS QUICKLY INCREASE OVR THE FA FROM THE
W AS THE ARCTIC AIR ALREADY BEGINS TO LIFT NWRD FROM OUR FA. SN
SHWRS OR VERY LGT STEADY SN WILL ACCOMPANY THE 850 MB WARM FRONT
WED NGT ACROSS CNTRL AND NRN PTNS OF THE FA WITH LITTLE IN THE WAY
OF ACCUMULATION.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
MODELS APPEAR TO BE MORE IN AGREEMENT WITH BRINGING THE SRN GULF
COAST STATES S/WV AND ASSOCIATED SFC LOW TOWARD OUR FA ON THU IN
ADVANCE OF THE STRONGER MORE AMPLIFIED S/WV FROM THE GREAT LKS.
THIS SHOULD KEEP THE TRACK OF THE SFC LOW E OF THE FA...AND INDEED
A MORE ERN GFS TRACK IS CURRENTLY BEING SUPPORTED BY THE 00Z
ECMWF AND NOW THE 00Z CANGEM SOLUTION...WHERE THE PRIOR 12Z
SOLUTION WAS AN OUTLIER...TAKING THE SFC LOW ON A WRN TRACK W OF
OUR FA...WHICH WOULD HAVE BROUGHT MILD ATLC AIR INTO ALL OF OUR FA
BY THU NGT. THE CANGEM PRECIP ONSET ALSO AGREES MORE WITH THE
FASTER GFS AND GFS ENS MEAN TIMING RATHER THAN THE SLOWER ECMWF
ONSET. ALL MODELS KEEP LLVL COLD AIR IN PLACE OVR THE FA N OF
DOWNEAST ME THU INTO THU EVE...BUT SHOW A NWRD PUNCH OF WARM AIR
ALF WHICH COULD LIKELY RESULT IN A PD OF MIXED PRECIP OVR E CNTRL
AND N CNTRL PTNS OF THE FA THU AFT AND EVE. MIXED PRECIP COULD
POSSIBLE REACH EVEN INTO FAR NRN PTNS OF THE FA THU EVE BEFORE COLD
MID LVL COLD ADVCN CHGS PRECIP BACK TO A PD OF ALL SN BEFORE
TAPERING TO SN SHWRS LATE THU NGT...BUT PRECIP TYPES AND TRANSITIONS
ACROSS THE FA REMAIN SPECULATIVE WITH THIS EVEN ATTM. WE NOTED
LESSER QPF SHOWN BY MOST LONGER RANGE MODELS WITH THIS SYSTEM...
AND IT COULD BE THAT THE S/WV MAY BE INITIALIZED THIS MODEL CYCLE
IN LOW RESOLUTION PTN OF THE MODEL DOMAIN...WHICH HAS HAPPENED
WITH SEVERAL OTHER SYSTEMS THIS PAST WINTER FROM DAYS 3 TO 6 OUT.
WE STILL KEEP POPS IN THE LIKELY CATEGORY DUE TO THIS UNCERTAINTY...
BUT STILL BELIEVE A SIG PRECIP SYSTEM IS LIKELY DURG THIS PD.
ALSO NOTED ON THIS MODEL CYCLE WAS THAT THE ECMWF BACKED OFF ITS
SECOND SFC LOW DEVELOPING WITH THE GREAT LKS S/WV FOR FRI INTO FRI
NGT AND APPEARS MORE LIKE THE 00Z GFS WITH THIS ASPECT OF THE
FCST. IF INDEED...THIS IS THE LIKELY OUTCOME...CLDS AND SN SHWRS
CAN BE XPCTD ON FRI WITH INCREASING LLVL COLD ADVCN AS SFC
REFLECTIONS FROM THE SRN AND NRN S/WVS MERGE OVR THE CAN MARITIME
PROVINCES. CLRG AS WELL AS COLD AND BRISK CONDITIONS IS XPCTD ATTM
FOR FRI NGT INTO SAT AS ARCTIC AIR FROM NRN CAN ADVECTS INTO THE
FA.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: MAINLY MVFR/VFR EXPECTED THROUGH THE PERIOD. THE NORTHERN
TERMINALS WILL REMAIN MVFR THROUGH MUCH OF TODAY DUE TO LOW CEILINGS
AND OCCASIONAL SNOW SHOWERS. FURTHER SOUTH...MVFR IS POSSIBLE EARLY
THIS MORNING IN PATCHY FOG BUT OVERALL EXPECT VFR CONDITIONS. SNOW
SHOWERS WILL END LATE THIS AFTERNOON AND SKIES CLEAR BY THIS
EVENING. VFR EXPECTED AT ALL SITES AFTER 00Z MONDAY.
SHORT TERM:VFR XPCTD ALL SITE XPCTD MON THRU MON EVE...THEN MVFR
LIKELY LATE MON NGT THROUGH TUE WITH SN SHWRS SPCLY NRN TAF SITES
WHERE BRIEF IFR IS POSSIBLE. CONDITIONS IMPROVE ALL SITES TO VFR
TUE NGT AND CONT WED. NEXT CHC OF MVFR WILL BEGIN LATE WED NGT
IN OCNL LGT SN WITH CONDITIONS LIKELY LOWERING TO IFR ON THU IN
STEADIER SN NRN FAR TAF SITES...MIXED PRECIP AT KHUL AND MSLY RN
FOR DOWNEAST SITES.
&&
.MARINE...
NEAR TERM: WINDS AND WAVES WILL REMAIN BELOW SMALL CRAFT LEVELS
TODAY AND TONIGHT SO NO HEADLINES WILL BE NEEDED.
SHORT TO LONG TERM: NO HDLNS MON THRU MOST OF MON NGT...WITH
MARGINAL SCA WINDS AND SEAS POSSIBLE ON TUE INTO ERLY TUE EVE
WITH SW FLOW AHEAD OF...AND BRIEF NW FLOW BEHIND A COLD FRONT.
WINDS AND SEAS SHOULD LOWER WELL BLO SCA CRITERIA LATE TUE NGT
THRU WED EVE...PERHAPS INCREASING TO SCA AHEAD OF LOW PRES FROM
THE SW LATE WED NGT INTO THU. WE USED A BLEND OF 00Z NAM12 AND GFS40
FOR SHORT TERM WINDS AND GFS40 AND GMOS FOR LONG TERM. WV HTS WERE
DERIVED FROM A BLEND OF WW3...SWAN NAM AND SWAN GFS GUIDANCE.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HASTINGS
SHORT TERM...VJN
LONG TERM...VJN
AVIATION...HASTINGS
MARINE...HASTINGS/VJN
AREA FORECAST DISCUSSION
NWS CARIBOU ME
546 AM EST SUN JAN 8 2012
.SYNOPSIS...
HIGH PRESSURE WILL BUILD ACROSS THE AREA TODAY THROUGH MONDAY.
ANOTHER LOW PRESSURE FROM CENTRAL CANADA WILL MOVE WELL NORTH OF
THE STATE ON TUESDAY. ANOTHER HIGH PRESSURE SYSTEM FROM NORTHERN
CANADA WILL BRIEFLY RIDGE ACROSS THE REGION ON WEDNESDAY BEHIND
A COLD FRONT LATE TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...AN EAST-WEST COLD FRONT CURRENTLY BISECTS THE FORECAST
AREA AND WILL CONTINUE TO SLOWLY SINK SOUTH TODAY. HAVE NOTED A THIN
STREAMER OF SNOW ACROSS NORTHERN SOMERSET AND PISCATAQUIS COUNTIES
EARLY THIS MORNING JUST ON THE NORTH SIDE OF THIS BOUNDARY. THIS
SHOULD GRADUALLY WEAKEN AND BE REPLACED BY ANOTHER STRONGER BAND A
BIT FURTHER NORTH AS WESTERLY WINDS BECOME MORE NORTHWEST. HAVE
UPDATED THE FORECAST TO ACCOUNT FOR THIS ACTIVITY...BUT NO OTHER
MAJOR CHANGES NEEDED.
PREVIOUS DISCUSSION...HIGH PRESSURE OVER THE GREAT LAKES WILL SLOWLY BUILD
EASTWARD TOWARD MAINE TODAY. A COLD FRONT THAT IS CURRENTLY DRAPED
ACROSS NORTHERN MAINE WILL SLIDE SOUTH THROUGH THE REMAINDER OF
THE AREA BY THIS AFTERNOON. SKIES HAVE CLEARED OVER THE SOUTHERN
THIRD OF THE FORECAST AREA WHILE NORTHERN AREAS REMAIN MOSTLY
CLOUDY BEHIND THE FRONT. COLDER AIR WILL SPILL INTO THE FORECAST
AREA THROUGH THE DAY AS NORTH FLOW PUSHES THE FRONT SOUTHWARD. THE
12KM NAM...3KM HRRR AND THE REGIONAL CANADIAN ALL INDICATE THAT A
NW-SE ORIENTED SNOW BAND WILL DEVELOP ACROSS THE FORECAST AREA
THIS MORNING...A RESULT OF THE COLDER AIR ALOFT MOVING OVER THE
RELATIVELY WARM WATERS OF THE SAINT LAWRENCE. THE BAND SHOULD SET
UP BY MID MORNING BUT WILL GRADUALLY DISSIPATE THIS AFTERNOON AS
THE FLOW LESSENS AS THE HIGH DRAWS NEAR. THE STEADIEST SNOW LOOKS
TO SET UP ACROSS THE NORTHERN MAINE WOODS AND EXTEND SOUTHEAST
TOWARD PATTEN AND KINGMAN WITH SNOWFALL AMOUNTS AROUND A HALF
INCH. ON EITHER SIDE AND DOWNWIND OF THIS BAND THERE`S JUST A
SLIGHT CHANCE OF SNOW SHOWERS SO LITTLE TO NO ACCUMULATION IS
EXPECTED IN THESE AREAS. AWAY FROM THE SNOWY AREAS...SKIES WILL BE
PARTLY TO MOSTLY SUNNY THROUGH THE DAY. THE SNOW SHOWERS WILL WANE
AND CLOUDS LESSEN LATE THIS AFTERNOON...WITH ALL AREAS MOSTLY
CLEAR BY THIS EVENING.
THE HIGH WILL BUILD OVER THE REGION OVERNIGHT TONIGHT...CRESTING
EARLY TOMORROW MORNING. CLEAR SKIES AND LIGHT WINDS WILL ALLOW FOR
GOOD RADIATIONAL COOLING. THEREFORE EXPECT A CHILLY NIGHT TONIGHT.
NORTHERN AREAS WILL BOTTOM OUT IN THE SINGLE DIGITS BELOW ZERO WHILE
THE USUAL COLD SPOTS IN NORTHWEST MAINE WILL DIP TO 10 TO 15 BELOW.
FURTHER SOUTH...CENTRAL AND SOUTHERN MAINE CAN EXPECT LOWS IN THE
SINGLE DIGITS ABOVE ZERO.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
SFC HI PRES WILL CROSS THE FA ON MON WITH PATCHY MID CLDNSS AS A
WEAK UPPER TROF MOVES EAST INTO THE MARITIMES. RETURN SW FLOW SETS
UP LATE IN THE DAY BEHIND THE HI AS MID CLDNSS INCREASES FROM THE
W IN THE EVE. A S/WV MOVG EWRD WILL THEN BRING SN SHWRS TO MSLY
NRN PTNS OF THE FA LATE MON NGT INTO TUE AS SFC LOW PRES TRACK
WELL N OF THE FA. UNLIKE THIS PAST EVENT...WHERE A STRONG W-E QUASI-
STATIONARY FRONTAL BOUNDARY WAS IN PLACE JUST S OF OUR FA TO
ENHANCE THE OVRRNG SNFL OVR SPCLY NRN PTNS OF THE FA...THIS S/WV
WILL NOT HAVE THIS TYPE OF BOUNDARY...SO SNFL IS ANTICIPATED TO
BE MUCH LIGHTER...WITH ARND AN INCH OVR FAR NRN PTNS OF THE FA
LATE MON NGT THRU TUE AND LESSER AMOUNTS PROGRESSIVELY FURTHER S.
A MDT SFC COLD FRONT BEHIND THE S/WV CROSSING THE FA LATE TUE AFTN
INTO EVE WILL BRING THE S FRINGE OF ARCTIC AIR BACK INTO SPCLY NRN
PTNS OF THE FA BY LATE TUE NGT INTO MORN WITH A BRISK EVENING WIND
SLACKENING BY WED MORN. CLDS QUICKLY INCREASE OVR THE FA FROM THE
W AS THE ARCTIC AIR ALREADY BEGINS TO LIFT NWRD FROM OUR FA. SN
SHWRS OR VERY LGT STEADY SN WILL ACCOMPANY THE 850 MB WARM FRONT
WED NGT ACROSS CNTRL AND NRN PTNS OF THE FA WITH LITTLE IN THE WAY
OF ACCUMULATION.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
MODELS APPEAR TO BE MORE IN AGREEMENT WITH BRINGING THE SRN GULF
COAST STATES S/WV AND ASSOCIATED SFC LOW TOWARD OUR FA ON THU IN
ADVANCE OF THE STRONGER MORE AMPLIFIED S/WV FROM THE GREAT LKS.
THIS SHOULD KEEP THE TRACK OF THE SFC LOW E OF THE FA...AND INDEED
A MORE ERN GFS TRACK IS CURRENTLY BEING SUPPORTED BY THE 00Z
ECMWF AND NOW THE 00Z CANGEM SOLUTION...WHERE THE PRIOR 12Z
SOLUTION WAS AN OUTLIER...TAKING THE SFC LOW ON A WRN TRACK W OF
OUR FA...WHICH WOULD HAVE BROUGHT MILD ATLC AIR INTO ALL OF OUR FA
BY THU NGT. THE CANGEM PRECIP ONSET ALSO AGREES MORE WITH THE
FASTER GFS AND GFS ENS MEAN TIMING RATHER THAN THE SLOWER ECMWF
ONSET. ALL MODELS KEEP LLVL COLD AIR IN PLACE OVR THE FA N OF
DOWNEAST ME THU INTO THU EVE...BUT SHOW A NWRD PUNCH OF WARM AIR
ALF WHICH COULD LIKELY RESULT IN A PD OF MIXED PRECIP OVR E CNTRL
AND N CNTRL PTNS OF THE FA THU AFT AND EVE. MIXED PRECIP COULD
POSSIBLE REACH EVEN INTO FAR NRN PTNS OF THE FA THU EVE BEFORE COLD
MID LVL COLD ADVCN CHGS PRECIP BACK TO A PD OF ALL SN BEFORE
TAPERING TO SN SHWRS LATE THU NGT...BUT PRECIP TYPES AND TRANSITIONS
ACROSS THE FA REMAIN SPECULATIVE WITH THIS EVEN ATTM. WE NOTED
LESSER QPF SHOWN BY MOST LONGER RANGE MODELS WITH THIS SYSTEM...
AND IT COULD BE THAT THE S/WV MAY BE INITIALIZED THIS MODEL CYCLE
IN LOW RESOLUTION PTN OF THE MODEL DOMAIN...WHICH HAS HAPPENED
WITH SEVERAL OTHER SYSTEMS THIS PAST WINTER FROM DAYS 3 TO 6 OUT.
WE STILL KEEP POPS IN THE LIKELY CATEGORY DUE TO THIS UNCERTAINTY...
BUT STILL BELIEVE A SIG PRECIP SYSTEM IS LIKELY DURG THIS PD.
ALSO NOTED ON THIS MODEL CYCLE WAS THAT THE ECMWF BACKED OFF ITS
SECOND SFC LOW DEVELOPING WITH THE GREAT LKS S/WV FOR FRI INTO FRI
NGT AND APPEARS MORE LIKE THE 00Z GFS WITH THIS ASPECT OF THE
FCST. IF INDEED...THIS IS THE LIKELY OUTCOME...CLDS AND SN SHWRS
CAN BE XPCTD ON FRI WITH INCREASING LLVL COLD ADVCN AS SFC
REFLECTIONS FROM THE SRN AND NRN S/WVS MERGE OVR THE CAN MARITIME
PROVINCES. CLRG AS WELL AS COLD AND BRISK CONDITIONS IS XPCTD ATTM
FOR FRI NGT INTO SAT AS ARCTIC AIR FROM NRN CAN ADVECTS INTO THE
FA.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: MAINLY MVFR/VFR EXPECTED THROUGH THE PERIOD. THE NORTHERN
TERMINALS WILL REMAIN MVFR THROUGH MUCH OF TODAY DUE TO LOW CEILINGS
AND OCCASIONAL SNOW SHOWERS. FURTHER SOUTH...MVFR IS POSSIBLE EARLY
THIS MORNING IN PATCHY FOG BUT OVERALL EXPECT VFR CONDITIONS. SNOW
SHOWERS WILL END LATE THIS AFTERNOON AND SKIES CLEAR BY THIS
EVENING. VFR EXPECTED AT ALL SITES AFTER 00Z MONDAY.
SHORT TERM:VFR XPCTD ALL SITE XPCTD MON THRU MON EVE...THEN MVFR
LIKELY LATE MON NGT THROUGH TUE WITH SN SHWRS SPCLY NRN TAF SITES
WHERE BRIEF IFR IS POSSIBLE. CONDITIONS IMPROVE ALL SITES TO VFR
TUE NGT AND CONT WED. NEXT CHC OF MVFR WILL BEGIN LATE WED NGT
IN OCNL LGT SN WITH CONDITIONS LIKELY LOWERING TO IFR ON THU IN
STEADIER SN NRN FAR TAF SITES...MIXED PRECIP AT KHUL AND MSLY RN
FOR DOWNEAST SITES.
&&
.MARINE...
NEAR TERM: WINDS AND WAVES WILL REMAIN BELOW SMALL CRAFT LEVELS
TODAY AND TONIGHT SO NO HEADLINES WILL BE NEEDED.
SHORT TO LONG TERM: NO HDLNS MON THRU MOST OF MON NGT...WITH
MARGINAL SCA WINDS AND SEAS POSSIBLE ON TUE INTO ERLY TUE EVE
WITH SW FLOW AHEAD OF...AND BRIEF NW FLOW BEHIND A COLD FRONT.
WINDS AND SEAS SHOULD LOWER WELL BLO SCA CRITERIA LATE TUE NGT
THRU WED EVE...PERHAPS INCREASING TO SCA AHEAD OF LOW PRES FROM
THE SW LATE WED NGT INTO THU. WE USED A BLEND OF 00Z NAM12 AND GFS40
FOR SHORT TERM WINDS AND GFS40 AND GMOS FOR LONG TERM. WV HTS WERE
DERIVED FROM A BLEND OF WW3...SWAN NAM AND SWAN GFS GUIDANCE.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HASTINGS
SHORT TERM...VJN
LONG TERM...VJN
AVIATION...HASTINGS
MARINE...HASTINGS/VJN
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1036 AM EST SUN JAN 8 2012
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE UPPER OHIO VALLEY AND ALLOW FOR
DRY AND MILD CONDITIONS THROUGH TUESDAY. A SURFACE LOW COMING FROM
THE SOUTHWEST WILL BRING RAIN TO THE AREA ON WEDNESDAY. MUCH
COLDER AIR IN THE WAKE OF THE LOW WILL BRING SNOW SHOWERS FOR THE
END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
15Z ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED TO MAKE
SLIGHT ADJUSTMENTS TO SKY GRIDS. OTHERWISE, ONGOING FORECAST
REMAINS UNCHANGED.
THE LATEST RUC MID-LEVEL ANALYSIS INDICATES A ZONAL FLOW ACROSS
THE UPPER OHIO VALLEY WITH AN AREA OF MID-LEVEL MOISTURE UPSTREAM
IN THE MISSOURI VALLEY. AT THE SURFACE, OBS/MSAS INDICATE A 1029MB
HIGH CENTERED ACROSS ILLINOIS. THIS BROAD AREA OF HIGH PRESSURE
EXTENDS FROM THE CENTRALS PLAINS ACROSS THE UPPER OHIO VALLEY AND
INTO THE MID-ATLANTIC. 12Z SOUNDING INDICATES SUBSIDENCE ABOVE
850MB WITH THE DRY WEATHER PATTERN CONTINUING. IN A NORTHWESTERLY
FLOW, MOISTURE FEED OFF OF LAKE ERIE IS PROVIDING STRATOCUMULUS
CLOUD COVERAGE THIS MORNING FOR AREAS MOSTLY NORTH AND EAST OF
PITTSBURGH.
THIS AFTERNOON AND TONIGHT...HIGH PRESSURE WILL SLIDE ACROSS THE
AREA, ALLOWING FOR DRY CONDITIONS TO CONTINUE. 850MB NORTHWESTERLY
FLOW WILL BRING MOSTLY CLOUDY SKIES TO AREAS NORTH AND EAST OF
PITTSBURGH. FLOW WILL BECOME ZONAL, WITH DRIER LOW-LEVEL AIR
ADVECTING INTO THE AREA. ALTHOUGH LOW-LEVEL CLOUDS WILL DIMINISH
ACROSS THE AREA BY THIS EVENING, BY THAT TIME, MID-LEVEL MOISTURE
WILL BEGIN TO ADVECT ACROSS THE AREA. THUS, MOSTLY CLOUDY IS THE
FORECAST OVERNIGHT.
FOR TEMPERATURES, HIGHS TODAY ARE A FEW DEGREES WARMER THAN LAMP
GUIDANCE. HIGHS WILL RANGE FROM THE MID 30S ALONG THE I-80
CORRIDOR TO THE MID 40S IN PORTIONS OF EASTERN OHIO AND NORTH-
CENTRAL WV. DESPITE TDS IN THE LOW 20S AND HIGH PRESSURE OVERHEAD
TONIGHT, MID-LEVEL CLOUD COVERAGE WILL SERVE TO LIMIT RADIATIONAL
COOLING. OVERNIGHT LOWS WILL RANGE FROM THE LOWER 20S ACROSS THE
EASTERN RIDGES TO UPPER 20S SOUTH OF THE I-70 CORRIDOR.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
HIGH PRESSURE WILL PROVIDE DRY WEATHER AND MILD TEMPERATURES
THROUGH THIS PERIOD.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
A CLOSED MID-LEVEL LOW WILL MOVE FROM THE WESTERN GULF STATES ACROSS
THE TENNESSEE VALLEY TUESDAY NIGHT INTO WEDNESDAY. THE CHANCE OF
RAIN WILL ARRIVE LATE TUESDAY NIGHT AS A WARM FRONT AHEAD OF THE LOW
PUSHES NORTHWARD INTO THE AREA. MODEL THICKNESSES WILL WARM ABOVE
CRITICAL THRESHOLDS THAT WOULD BE NEEDED FOR A WINTRY MIX, SO
FORECAST IS FOR ALL RAIN TO BEGIN THE EVENT. TEMPERATURES WILL BE
AROUND 10 DEGREES ABOVE NORMAL THROUGH THE MID-WEEK.
RAIN WILL BE LIKELY ACROSS THE REGION WEDNESDAY INTO WEDNESDAY NIGHT
AS THE LOW MOVES ACROSS WEST VIRGINIA AND INTO THE NORTHEAST. BY
THURSDAY MORNING LOW WILL BE EXITING EAST AS QUITE STRONG NORTHERN
BRANCH CLOSED UPPER LOW DIGS ACROSS THE GREAT LAKES. THIS NORTHERN
BRANCH LOW WILL BRING MUCH COLDER AIR INTO REGION STARTING THURSDAY
AND CONTINUING INTO THE START OF THE WEEKEND. RAIN SHOWERS WILL MIX
WITH AND CHANGE TO SNOW THURSDAY FOLLOWED BY NORTHWEST FLOW SNOW
SHOWERS INTO FRIDAY. BY SATURDAY A RIDGE OF HIGH PRESSURE WILL BRING
DRY AND COLD CONDITIONS. AS ALSO SUPPORTED BY NAEFS MEDIAN VALUES
TEMPERATURES WILL FALL TO 5 TO 10 DEGREES BELOW NORMAL LATE WEEK.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
VFR REMAINDER OF DAY AS DECK OF BKN-OVC SC WILL CONTINUE TO SHIFT
EAST WITH MID-LEVEL COLD POOL. CLOUDS WILL ERODE BY LATE AFTERNOON
AS WAA BEGINS.
OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...
VFR INTO TUESDAY NIGHT. NORTHEASTBOUND LOW PRESSURE FROM LOUISIANA
WILL PROVIDE MIXED PRECIPITATION AND RESTRICTIONS WEDNESDAY AND
THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS RALEIGH NC
952 AM EST SUN JAN 8 2012
.SYNOPSIS...
A COLD FRONT WILL STALL JUST SOUTH OF THE AREA TODAY. WEAK WAVES OF
LOW PRESSURE WILL DEVELOP ALONG THE FRONT TONIGHT INTO MONDAY...
RESULTING IN COOL AND DAMP CONDITIONS. DRY HIGH PRESSURE WILL RETURN
ON TUESDAY...FOLLOWED BY A POTENT STORM SYSTEM EXPECTED TO TRACK
ACROSS THE CAROLINAS ON WEDNESDAY.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 952 AM SUNDAY...
FOR THE REST OF TODAY: LATEST OBSERVED WEATHER TRENDS REMAIN IN LINE
WITH THE EARLIER FORECAST. THE MOST RECENT SURFACE ANALYSES SHOW THE
COLD FRONT MAKING SLOW BUT STEADY SOUTHWARD PROGRESS THROUGH THE FAR
SOUTHERN CWA... WHILE SPRAWLING HIGH PRESSURE CENTERED OVER IL (AND
STRETCHING FROM THE HEARTLAND ACROSS THE MIDATLANTIC) ATTEMPTS TO
BUILD INTO CENTRAL NC. WHILE THE PATCHY LIGHT RAIN FROM EARLY THIS
MORNING HAS DISSIPATED AND EXITED... A BROKEN DECK OF CLOUDS
CONTINUES TO PUSH SLOWLY EASTWARD INTO OUR AREA... HAVING OVERSPREAD
ALL BUT THE EASTERN CWA THUS FAR. PATCHY SPRINKLES FORCED BY MASS
CONVERGENCE NEAR THE LOW LEVEL FRONTAL ZONE WILL REMAIN A
POSSIBILITY OVER THE SOUTHWEST AND SOUTHERN CWA FOR THE NEXT SEVERAL
HOURS... SO HAVE SLIGHTLY SPED UP THE TIMING OF PRECIP ARRIVAL HERE
BY A COUPLE OF HOURS. THIS INITIAL PRECIP SHOULD REMAIN VERY LIGHT
GIVEN THE LACK OF ANY STRONG LIFT AND THE SHALLOW NATURE OF THE
INCOMING MOIST ISENTROPIC UPGLIDE. A BETTER CHANCE OF RAIN WILL
ARRIVE AFTER 4 PM THIS AFTERNOON AS THE UPGLIDE-SUPPORTED PRECIP NOW
OVER TN/AL/GA -- ENHANCED BY A WEAK SURFACE LOW ALONG THE FRONT --
SPREADS INTO CENTRAL NC. BOTH EXTRAPOLATION AND RECENT HRRR RUNS
SUPPORT THIS TIMING. AFTERNOON TEMP RISE WILL BE LESS THAN TYPICAL
GIVEN THE INCOMING CLOUDS AND LOW LEVEL COLD AIR ADVECTION...
HOWEVER THIS ADVECTION WILL BE QUITE WEAK AND WE STILL ANTICIPATE
POCKETS OF SUNSHINE THIS AFTERNOON. HAVE NUDGED HIGHS UP A BIT TO
55-62. -GIH
TONIGHT:
THE 00Z GFS/NAM/ECMWF ALL SHOW ISENTROPIC LIFT STRENGTHENING OVER
THE AREA TONIGHT FROM THE SOUTHWEST AS THE AFOREMENTIONED LOW-LEVEL
RIDGE PROGRESSES SLOWLY EASTWARD TO THE BAHAMAS...RESULTING IN A
MORE FAVORABLE LOW-LEVEL GULF RETURN FLOW OVER THE CAROLINAS THAT
WILL OVERRUN THE COOL/DRY AIRMASS DEPOSITED IN THE WAKE OF THE
BACKDOOR COLD FRONT THIS MORNING. ALL OF THE MODEL GUIDANCE SHOWS A
TRACE TO SEVERAL HUNDREDTHS OF AN INCH OF RAIN ACROSS THE AREA
OVERNIGHT...ALTHOUGH JUST HOW WIDESPREAD PRECIPITATION WILL BE
REMAINS IN QUESTION. WILL CONTINUE TO SHOW A 50% CHANCE OF RAIN OVER
THE ENTIRE AREA OVERNIGHT...WITH PRECIPITATION AMOUNTS GENERALLY A
FEW HUNDREDTHS OF AN INCH OR LESS (NAM/ECMWF). THE GFS REMAINS AN
OUTLIER...SHOWING 0.10-0.15". LOWS TONIGHT WILL HIGHLY DEPEND ON
WHERE AND HOW MUCH PRECIPITATION OCCURS. WHERE PRECIP DOES OCCUR...
GIVEN THE COOL/DRY SURFACE AIRMASS IN PLACE...A HYBRID CAD WEDGE
WILL DEVELOP...AND EVAP COOLING WOULD KEEPS TEMPS A FEW DEGREES
LOWER THAN AREAS WITHOUT PRECIP. GIVEN THE AFOREMENTIONED
UNCERTAINTY...AT THIS TIME WILL CONTINUE TO FOLLOW MOS GUIDANCE...
WITH LOWS RANGING FROM THE UPPER 30S IN THE NORTH TO LOWER 40S IN
THE SOUTH. -VINCENT
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
AS OF 330 AM SUNDAY...
MONDAY:
THE WEAKENING SHEAR AXIS EXTENDING ENE FROM THE CENTRAL PLAINS INTO
NEW ENGLAND BY 12Z MONDAY IS PROGGED TO CONTINUE WEAKENING AS IT
PROGRESSES EAST OR ESE TOWARD THE MID-ATLANTIC ON MONDAY. THE
AFOREMENTIONED SHORTWAVE DIGGING SOUTHEAST INTO THE UPPER GREAT
LAKES BY 12Z MON IS PROGGED TO DIG INTO THE LOWER GREAT LAKES BY 00Z
TUESDAY...AND IS GENERALLY EXPECTED TO REMAIN TOO FAR NORTH TO HAVE
MUCH INFLUENCE ON CENTRAL NC DURING THE DAY MON. HOWEVER...THE SHEAR
AXIS (AND AN ASSOCIATED WEAK LOW-LEVEL TROUGH) PROGRESSING TOWARD
THE AREA SHOULD PROVIDE SUFFICIENT FORCING FOR PRECIPITATION VIA A
COMBINATION OF DPVA AND LOW/MID LEVEL ISENTROPIC LIFT. EXPECT PATCHY
DRIZZLE/LIGHT RAIN TO BE ONGOING MONDAY MORNING IN ASSOC/W
RELATIVELY WEAK ISENTROPIC LIFT...AND WILL CONTINUE TO SHOW A 50%
CHANCE OF RAIN EVERYWHERE THROUGH NOON. AFTER NOON...THE BETTER
FORCING MENTIONED ABOVE WILL ARRIVE...AND WILL INCREASE POPS TO
LIKELY (60%) GIVEN THAT MOST OF THE MODEL GUIDANCE (NAM/ECMWF) SHOWS
MEASURABLE PRECIP OVER CENTRAL NC MONDAY AFTERNOON (GFS AN OUTLIER
WITH BARELY MORE THAN A TRACE)...WITH ADDITIONAL SUPPORT FROM THE
NCEP HIGH-RES WRF-NMM WHICH SHOWS A WIDESPREAD SWATH OF RAIN
CROSSING CENTRAL NC FROM WEST-EAST BETWEEN ROUGHLY 18-00Z. HIGHS ON
MONDAY ARE DIFFICULT TO ASCERTAIN GIVEN SOME QUESTION WITH THE
LOCATION/EXTENT OF RAIN/DRIZZLE PRIOR EARLY IN THE DAY PRIOR TO THE
MORE WIDESPREAD RAIN EXPECTED IN THE AFTERNOON. REGARDLESS...EXPECT
A HYBRID OR IN-SITU CAD WEDGE TO DEVELOP...WITH HIGHS COOLER THAN IN
PREVIOUS DAYS. WILL INDICATE HIGHS RANGING FROM THE UPPER 40S N/NW
PIEDMONT TO LOWER 50S ELSEWHERE. IT IS POSSIBLE THAT HIGHS MAY NOT
EXCEED THE MID/UPPER 40S IF DRIZZLE OR LIGHT RAIN IS PREVALENT
THROUGH THE MORNING AND EARLY AFTERNOON HOURS PRIOR TO THE POTENTIAL
FOR MORE WIDESPREAD RAIN MOVING ACROSS THE AREA FROM WEST-EAST
MID/LATE AFTERNOON.
MONDAY NIGHT:
PRECIP ASSOC/W THE SHEAR AXIS AND RESULTING LOW/MID LEVEL ISENTROPIC
LIFT MON AFTERNOON SHOULD END BY 00-03Z TUE AS THE SHEAR AXIS
PROGRESSES OFFSHORE. THE AFOREMENTIONED H5 SHORTWAVE DIGGING INTO
THE LOWER GREAT LAKES DURING THE DAY MONDAY IS PROGGED TO AMPLIFY AS
IT DIGS INTO NEW ENGLAND AND THE MID-ATLANTIC BY 06Z TUE...FURTHER
AMPLIFYING AS IT PROGRESSES OFFSHORE THE MID-ATLANTIC BETWEEN
06-12Z. THIS AMPLIFYING UPPER LEVEL TROUGH WILL INITIATE
CYCLOGENESIS OFFSHORE THE CAROLINA COAST MON NIGHT AND RESULT IN A
FORMIDABLE EXTRATROPICAL CYCLONE IN THE NORTH ATLANTIC DURING THE
DAY TUE. OVER CENTRAL NC...HEIGHT/RISES SYNOPTIC SUBSIDENCE IN THE
WAKE OF THE SHEAR AXIS AND UPPER LEVEL TROUGH WILL RAPIDLY WARM/DRY
THE MID AND UPPER LEVELS AFTER 00-03Z TUE...IN ADDITION TO PRESSURE
RISES UPSTREAM IN THE OH VALLEY AND MID-ATLANTIC WHICH SHOULD HELP
FORCE A DRIER LOW-LEVEL AIRMASS INTO THE AREA BY 12Z TUE. IT IS
STILL NOT CLEAR WHETHER OR NOT THE CAD WEDGE WILL ENTIRELY SCOUR OUT
BY SUNRISE TUE. MODEL SOUNDINGS CONTINUE TO SHOW A VERY SHALLOW
SATURATED LAYER PERSISTING THROUGH 12Z TUE...AND HIGH PRESSURE
UPSTREAM OF THE AREA MAY NOT BE STRONG ENOUGH TO RESULT IN
APPRECIABLE SURFACE COLD ADVECTION TO COMPLETELY SCOUR OUT THE
WEDGE. WITH THE ABOVE IN MIND...UNCERTAINTY PERSISTS W/REGARD TO
CLOUD COVER AND LOW TEMPS. WILL SHOW AT LEAST A CLEARING TREND...
WITH LOWS RANGING FROM THE UPPER 30S TO LOWER 40S. -VINCENT
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 245 AM SUNDAY...
THE EJECTION OF THE MID-UPPER LOW FROM THE SOUTHWEST IS THE MAIN
WEATHER FEATURE TO WATCH THIS PERIOD... ALONG WITH A TURN TO COLDER
CONDITIONS LATE IN THE WEEK AND NEXT WEEKEND. OUT AHEAD OF THIS
STORM... IT WILL BECOME VERY MILD TO WARM AGAIN WITH TEMPERATURES
AVERAGING 10-15 DEGREES ABOVE THE 30 YEAR NORMALS.
THE MID-UPPER LOW IS ALREADY CUT OFF FROM THE MAIN WESTERLIES AND
THIS FAVORS THE MORE SOUTHERN AND SLOWER FORECASTS THAT THE NEW
EUROPEAN MODEL SUITE INDICATES. HOWEVER... NEARLY ALL MODEL GUIDANCE
INDICATES A FAIRLY SIMILAR SYSTEM WILL AFFECT OUR REGION CENTERED
AROUND WED-WED NIGHT... BUT THE TRACK IS OF CONCERN AS SOME MODELS
TRACK THE MID LEVEL CIRCULATION OVERHEAD... SOME TO OUR NW AND SOME
TO OUR SE. THE EXACT TRACK WILL DICTATE MANY ASPECTS OF THE SYSTEM
FOR OUR REGION... INCLUDING QPF/THUNDER CHANCES/TEMPS. FOR NOW... WE
WILL MAINTAIN OUR CURRENT FORECASTS... AND INCORPORATE A SLIGHTLY
SLOWER AND EVEN MORE MOIST SYSTEM PER THE LATEST EUROPEAN MODEL. IN
ADDITION... IF THE EUROPEAN TRACK VERIFIES... WE WOULD GE A
SIGNIFICANT RAIN WITH 1 TO 1.5 INCHES ACROSS THE REGION.
AFTER THE SYSTEM PASSES... IT WILL TURN COLDER... BUT REALLY NOT
UNTIL FRIDAY WHEN THE MAIN PUSH OF CAA IS EXPECTED. THERE IS STILL
QUITE A BIT OF DIFFERENCES IN THE MODEL FORECASTS AFTER FRIDAY WITH
THE CANADIAN INDICATING ANOTHER SOUTHERN BRANCH SYSTEM. MORE ON THIS
LATER.
SENSIBLE WEATHER HIGHLIGHTS... TUESDAY... SOME MORNING DRIZZLE...
BECOMING PARTLY CLOUDY AND WARMING INTO THE 60S. WEDNESDAY...
PERIODS OF RAIN WITH HIGHS 55-65. THURSDAY... RAIN ENDING. PARTLY
CLOUDY. HIGHS IN THE 60S. FRIDAY... TURNING COLDER AND BREEZY. HIGHS
IN THE 50S.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 645 AM SUNDAY...
24-HR TAF PERIOD:
VFR CONDITIONS ARE EXPECTED TO PREDOMINATE THROUGH ~00Z THIS
EVENING...WITH CONDITIONS DETERIORATING THEREAFTER. A BACKDOOR COLD
FRONT WILL PROGRESS SOUTH THROUGH CENTRAL NC THIS MORNING BEFORE
STALLING OUT JUST SOUTH OF THE AREA THIS AFTERNOON. VFR CEILINGS IN
THE 4-7 KFT RANGE ARE EXPECTED TO PREDOMINATE THIS AFTERNOON. BY OR
SHORTLY AFTER 00Z...LOW-LEVEL (925-850 MB) FLOW WILL ASSUME MORE OF
A SOUTHERLY COMPONENT...RESULTING IN OVERRUNNING AND THE DEVELOPMENT
OF MVFR CEILINGS AND AREAS OF LIGHT RAIN...WITH A POTENTIAL FOR
CONDITIONS TO FURTHER DETERIORATE TO IFR AND POSSIBLY LIFR BY 12Z
MON. WHETHER OR NOT IFR/LIFR CONDITIONS DEVELOP PRIOR TO 12Z MON
WILL HEAVILY DEPEND ON WHETHER OR NOT MEASURABLE PRECIPITATION
DEVELOPS AND PERSISTS IN VICINITY OF THE TAF SITES.
LOOKING AHEAD:
CONDITIONS ARE EXPECTED TO FURTHER DETERIORATE TO IFR AND
POTENTIALLY LIFR OVER CENTRAL NC ON MONDAY AS PRECIPITATION FALLING
INTO THE INITIALLY COOL/DRY AIRMASS IN PLACE RESULTS IN THE
DEVELOPMENT OF A COLD AIR DAMMING WEDGE. SOME UNCERTAINTY PERSISTS
W/REGARD TO THE STRENGTH OF THE CAD WEDGE AND WHETHER OR NOT
CEILINGS WILL BECOME IFR/LIFR OR REMAIN MVFR OR BORDERLINE IFR. IF
WIDESPREAD LIGHT RAIN DEVELOPS TONIGHT AND PERSISTS INTO MONDAY...
THEN THE IFR/LIFR SCENARIO WOULD BE MORE LIKELY. CONVERSELY...IF
PRECIPITATION IS INTERMITTENT AND PATCHY...THEN MVFR OR BORDERLINE
IFR CEILINGS WOULD BE MORE LIKELY. CONDITIONS ARE EXPECTED TO
IMPROVE TO VFR EITHER LATE MONDAY NIGHT OR SHORTLY AFTER SUNRISE
TUESDAY AS DRY HIGH PRESSURE BUILDS BACK INTO THE AREA FROM THE
WEST/NW. HOWEVER...VFR CONDITIONS WILL BE SHORT-LIVED AS A POTENT
UPPER LEVEL LOW AND ASSOCIATED SFC LOW PRESSURE SYSTEM ARE PROGGED
TO TRACK OVER THE CAROLINAS/VA MID-WEEK. EXPECT CONDITIONS TO
DETERIORATE TUE NIGHT...WITH WIDESPREAD RAIN AND SUB-VFR CONDITIONS
DURING THE DAY WED...FOLLOWED BY A RETURN TO VFR CONDITIONS IN THE
WAKE OF A COLD FRONTAL PASSAGE WED EVE/NIGHT. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT/GIH
NEAR TERM...HARTFIELD/VINCENT
SHORT TERM...VINCENT
LONG TERM...BADGETT
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
952 AM CST SUN JAN 8 2012
.UPDATE...
FORECAST LOOKS ON TRACK OVERALL. INVERTED SURFACE TROUGH/STALLED
OLD FRONT REMAIN ANCHORED OVER FAR EASTERN COUNTIES THIS MORNING.
PATCHY DENSE FOG HAS FORMED ALONG/NORTH OF I-20 AND MAINLY EAST OF
I-35W THIS MORNING. CONDITIONS SHOULD IMPROVE THROUGH MIDDAY WITH
NORTH WINDS INCREASING TO NEAR 10 MPH THIS AFTERNOON. WE WILL
HANDLE ANY FOG SHORT TERM FORECASTS...VERSUS A FULL PACKAGE UPDATE.
EXTENSIVE CLOUD COVER EXISTS WHICH WILL KEEP TEMPERATURES COOL
THROUGHOUT DAY. CURRENT HIGHS LOOK REPRESENTATIVE WITH A SMALL
DIURNAL RISE IN TEMPERATURES EXPECTED TODAY. HAVE LEFT SLIGHT
CHANCES OF RAIN FOR LATER THIS AFTERNOON WELL SOUTH OF I-20 WHERE
ISENTROPIC ASCENT SHOULD BEGIN IN EARNEST BY THIS EVENING.
WILL ONLY SEND MATRIX AND IMAGE PRODUCT UPDATES THIS MORNING.
05/
&&
.AVIATION...
STRATUS REMAINS JUST NORTH OF THE DALLAS-FORT WORTH METRO AREA
TERMINALS EARLY THIS MORNING. LATEST HRRR GUIDANCE SLOWLY ADVECTS
CLOUDS SOUTH OVER THE AREA. RECENT BREAKS IN THE HIGH CLOUDS
REVEAL A SLIGHT SOUTHWARD EXPANSION OF THE CLOUD DECK WITH TIME ON
11-3.9 MICRON LOOP. AS A RESULT...WILL CONTINUE WITH THE
INTRODUCTION OF MVFR CIGS TO MAJOR AIRPORTS...BUT PUSH BACK TIMING
TO 14-15Z. IF AND WHEN STRATUS SINK FAR ENOUGH SOUTH TO COVER
METRO AREA TAF SITES...FEEL IT WILL HAVE A HARD TIME ERODING AS
OVERRUNNING WILL INCREASE LATER TODAY FURTHER TRAPPING THE
MOISTURE BENEATH THE INVERSION. THERE MAY BE SOME BREAKS DURING PEAK
HEATING HOURS THIS AFTERNOON BUT FEEL THIS WOULD BE SHORT LIVED IF
AT ALL. EXPECT CLOUDS TO LOWER AND RAIN TO BEGIN AREA WIDE AROUND OR
SHORTLY AFTER MIDNIGHT LOCAL AS ISENTROPIC LIFT CONTINUES TO
INCREASE...AND WILL CONSEQUENTLY SHOW IFR CIGS AND PREDOMINANT
LIGHT RAIN AFTER 06Z. ISOLATED THUNDERSTORMS ARE POSSIBLE BY
MONDAY MORNING...WILL NOT INCLUDE TS IN TAFS AT THIS TIME AS
COVERAGE SHOULD BE LOW AND EXACT TIMING OF CONVECTION WOULD BE
MUCH BETTER RECOGNIZED LATER TODAY AND TONIGHT AS NEW MODEL DATA
IS RECEIVED.
30
&&
.PREV DISCUSSION... /ISSUED 417 AM CST SUN JAN 8 2012/
UNSETTLED WEATHER WILL PREVAIL ACROSS NORTH TEXAS THE NEXT FEW
DAYS AS ENERGY FROM A DEEP UPPER TROUGH INTERACTS WITH LOW LEVEL
MOISTURE ABOVE A WEDGE OF COOL AIR AT THE SURFACE. TODAY WILL BE
CLOUDY AND COOL ACROSS NORTH TEXAS WITH AFTERNOON MAINLY IN THE
50S. A FEW SHOWERS MAY DEVELOP IN THE SOUTHEAST LATE THIS
AFTERNOON AS LIFT INCREASES OVER A STALLED COLD FRONT OVER SOUTH
TEXAS. UPPER LEVEL DIFFLUENCE WILL SET UP TONIGHT AS THE CLOSED
LOW ROTATES INTO FAR WEST TEXAS. RAIN CHANCES WILL BE ON THE
INCREASE THROUGH THE NIGHT AND INTO MONDAY WITH INCREASING
ISENTROPIC LIFT AND LARGE SCALE FORCING. MID LEVEL LAPSE RATES
SHOULD BE SUFFICIENT TO SUPPORT ISOLATED THUNDERSTORMS ACROSS THE
ENTIRE REGION. THE CORE OF THE UPPER LOW IS PROGGED TO TRACK
ACROSS THE NORTHERN HALF OF NORTH TEXAS MONDAY NIGHT THROUGH
TUESDAY. RAIN CHANCES SHOULD CONTINUE ACROSS THE ENTIRE REGION AND
THE RAIN MAY MIX WITH SOME LIGHT SNOW ACROSS THE WESTERN COUNTIES
MAINLY MONDAY NIGHT/TUESDAY MORNING. NO SNOW ACCUMULATIONS ARE
EXPECTED AT THIS TIME AS SURFACE TEMPERATURES SHOULD REMAIN ABOVE
FREEZING. IT APPEARS THAT THE BETTER CHANCES FOR SNOW WILL BE
ACROSS PORTIONS OF THE CONCHO VALLEY AND BIG COUNTRY WHERE DEEPER
COLD AIR IS EXPECTED. PRECIPITATION CHANCES WILL LINGER THROUGH
TUESDAY AFTERNOON...ESPECIALLY ALONG THE RED RIVER...NEAR THE
TRACK OF THE UPPER LOW. ALL PRECIPITATION WILL END TUESDAY EVENING
AS DRY AND SUBSIDENT AIR MOVES IN BEHIND THE DEPARTING SYSTEM.
THIS IS STILL SHAPING UP TO BE A GOOD PRECIPITATION PRODUCER FOR
NORTH TEXAS WITH AVERAGE RAINFALL TOTALS ON THE ORDER OF ONE TO
TWO INCHES.
THE FORECAST FOR THE MIDDLE OF THE WEEK THROUGH THE WEEKEND WILL
BE CHALLENGING TO SAY THE LEAST AS THE EXTENDED MODELS ARE NOT IN
AGREEMENT WITH REGARDS TO THE FATE OF ANOTHER SOUTHERN STREAM
TROUGH FORECAST TO DEVELOP OFF THE WEST COAST. THE ONE THING THAT
ALL THE GUIDANCE IS IN AGREEMENT ON IS THAT A STRONG COLD FRONT
WILL MOVE ACROSS THE REGION WEDNESDAY NIGHT THROUGH THURSDAY AS A
HIGH AMPLITUDE RIDGE BUILDS OFF THE WEST COAST. THE GFS AND
CANADIAN SOLUTIONS ARE VERY PROGRESSIVE AND BRING THE UPPER TROUGH
ACROSS NORTH TEXAS RIGHT AFTER THE COLD AIR MOVES IN WHICH WOULD
RESULT IN SOME WINTER PRECIP FOR PORTIONS OF NORTH TEXAS. THE
ECMWF AND 06Z DGEX SOLUTIONS CUT THE UPPER LOW OFF FROM THE MEAN
FLOW AND DO NOT BRING IT ACROSS TEXAS UNTIL LATE SATURDAY OR
SUNDAY. FOR NOW WE HAVE OPTED FOR THE DRIER AND SLOWER ECMWF AND
DGEX SOLUTIONS BASED ON PATTERN RECOGNITION. WE WILL HAVE TO WATCH
THIS SYSTEM CLOSELY IN THE COMING DAYS SINCE IT HAS POTENTIAL TO
CAUSE SOME IMPACTS LATE IN THE WEEK.
OTHERWISE...EXPECT A COOLER WEEK THAN THE FIRST WEEK OF JANUARY WITH
HIGHS MAINLY IN THE 40S AND 50S AND LOWS GENERALLY IN THE 30S.
79
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 54 43 48 41 49 / 10 80 100 70 30
WACO, TX 58 46 52 36 53 / 20 90 100 50 20
PARIS, TX 57 42 50 46 53 / 10 70 100 90 50
DENTON, TX 53 39 45 39 49 / 10 70 90 80 30
MCKINNEY, TX 55 42 49 41 49 / 10 70 100 80 40
DALLAS, TX 55 44 49 42 49 / 10 80 100 70 30
TERRELL, TX 58 45 52 42 52 / 10 80 100 80 30
CORSICANA, TX 60 49 56 40 52 / 20 90 100 70 30
TEMPLE, TX 58 46 51 38 56 / 20 90 100 40 20
MINERAL WELLS, TX 53 37 42 35 47 / 10 70 90 60 20
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
30/05
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
533 AM CST SUN JAN 8 2012
.AVIATION...
STRATUS REMAINS JUST NORTH OF THE DALLAS-FORT WORTH METRO AREA
TERMINALS EARLY THIS MORNING. LATEST HRRR GUIDANCE SLOWLY ADVECTS
CLOUDS SOUTH OVER THE AREA. RECENT BREAKS IN THE HIGH CLOUDS
REVEAL A SLIGHT SOUTHWARD EXPANSION OF THE CLOUD DECK WITH TIME ON
11-3.9 MICRON LOOP. AS A RESULT...WILL CONTINUE WITH THE
INTRODUCTION OF MVFR CIGS TO MAJOR AIRPORTS...BUT PUSH BACK TIMING
TO 14-15Z. IF AND WHEN STRATUS SINK FAR ENOUGH SOUTH TO COVER
METRO AREA TAF SITES...FEEL IT WILL HAVE A HARD TIME ERODING AS
OVERRUNNING WILL INCREASE LATER TODAY FURTHER TRAPPING THE
MOISTURE BENEATH THE INVERSION. THERE MAY BE SOME BREAKS DURING PEAK
HEATING HOURS THIS AFTERNOON BUT FEEL THIS WOULD BE SHORT LIVED IF
AT ALL. EXPECT CLOUDS TO LOWER AND RAIN TO BEGIN AREA WIDE AROUND OR
SHORTLY AFTER MIDNIGHT LOCAL AS ISENTROPIC LIFT CONTINUES TO
INCREASE...AND WILL CONSEQUENTLY SHOW IFR CIGS AND PREDOMINANT
LIGHT RAIN AFTER 06Z. ISOLATED THUNDERSTORMS ARE POSSIBLE BY
MONDAY MORNING...WILL NOT INCLUDE TS IN TAFS AT THIS TIME AS
COVERAGE SHOULD BE LOW AND EXACT TIMING OF CONVECTION WOULD BE
MUCH BETTER RECOGNIZED LATER TODAY AND TONIGHT AS NEW MODEL DATA
IS RECEIVED.
30
&&
.PREV DISCUSSION... /ISSUED 417 AM CST SUN JAN 8 2012/
UNSETTLED WEATHER WILL PREVAIL ACROSS NORTH TEXAS THE NEXT FEW
DAYS AS ENERGY FROM A DEEP UPPER TROUGH INTERACTS WITH LOW LEVEL
MOISTURE ABOVE A WEDGE OF COOL AIR AT THE SURFACE. TODAY WILL BE
CLOUDY AND COOL ACROSS NORTH TEXAS WITH AFTERNOON MAINLY IN THE
50S. A FEW SHOWERS MAY DEVELOP IN THE SOUTHEAST LATE THIS
AFTERNOON AS LIFT INCREASES OVER A STALLED COLD FRONT OVER SOUTH
TEXAS. UPPER LEVEL DIFFLUENCE WILL SET UP TONIGHT AS THE CLOSED
LOW ROTATES INTO FAR WEST TEXAS. RAIN CHANCES WILL BE ON THE
INCREASE THROUGH THE NIGHT AND INTO MONDAY WITH INCREASING
ISENTROPIC LIFT AND LARGE SCALE FORCING. MID LEVEL LAPSE RATES
SHOULD BE SUFFICIENT TO SUPPORT ISOLATED THUNDERSTORMS ACROSS THE
ENTIRE REGION. THE CORE OF THE UPPER LOW IS PROGGED TO TRACK
ACROSS THE NORTHERN HALF OF NORTH TEXAS MONDAY NIGHT THROUGH
TUESDAY. RAIN CHANCES SHOULD CONTINUE ACROSS THE ENTIRE REGION AND
THE RAIN MAY MIX WITH SOME LIGHT SNOW ACROSS THE WESTERN COUNTIES
MAINLY MONDAY NIGHT/TUESDAY MORNING. NO SNOW ACCUMULATIONS ARE
EXPECTED AT THIS TIME AS SURFACE TEMPERATURES SHOULD REMAIN ABOVE
FREEZING. IT APPEARS THAT THE BETTER CHANCES FOR SNOW WILL BE
ACROSS PORTIONS OF THE CONCHO VALLEY AND BIG COUNTRY WHERE DEEPER
COLD AIR IS EXPECTED. PRECIPITATION CHANCES WILL LINGER THROUGH
TUESDAY AFTERNOON...ESPECIALLY ALONG THE RED RIVER...NEAR THE
TRACK OF THE UPPER LOW. ALL PRECIPITATION WILL END TUESDAY EVENING
AS DRY AND SUBSIDENT AIR MOVES IN BEHIND THE DEPARTING SYSTEM.
THIS IS STILL SHAPING UP TO BE A GOOD PRECIPITATION PRODUCER FOR
NORTH TEXAS WITH AVERAGE RAINFALL TOTALS ON THE ORDER OF ONE TO
TWO INCHES.
THE FORECAST FOR THE MIDDLE OF THE WEEK THROUGH THE WEEKEND WILL
BE CHALLENGING TO SAY THE LEAST AS THE EXTENDED MODELS ARE NOT IN
AGREEMENT WITH REGARDS TO THE FATE OF ANOTHER SOUTHERN STREAM
TROUGH FORECAST TO DEVELOP OFF THE WEST COAST. THE ONE THING THAT
ALL THE GUIDANCE IS IN AGREEMENT ON IS THAT A STRONG COLD FRONT
WILL MOVE ACROSS THE REGION WEDNESDAY NIGHT THROUGH THURSDAY AS A
HIGH AMPLITUDE RIDGE BUILDS OFF THE WEST COAST. THE GFS AND
CANADIAN SOLUTIONS ARE VERY PROGRESSIVE AND BRING THE UPPER TROUGH
ACROSS NORTH TEXAS RIGHT AFTER THE COLD AIR MOVES IN WHICH WOULD
RESULT IN SOME WINTER PRECIP FOR PORTIONS OF NORTH TEXAS. THE
ECMWF AND 06Z DGEX SOLUTIONS CUT THE UPPER LOW OFF FROM THE MEAN
FLOW AND DO NOT BRING IT ACROSS TEXAS UNTIL LATE SATURDAY OR
SUNDAY. FOR NOW WE HAVE OPTED FOR THE DRIER AND SLOWER ECMWF AND
DGEX SOLUTIONS BASED ON PATTERN RECOGNITION. WE WILL HAVE TO WATCH
THIS SYSTEM CLOSELY IN THE COMING DAYS SINCE IT HAS POTENTIAL TO
CAUSE SOME IMPACTS LATE IN THE WEEK.
OTHERWISE...EXPECT A COOLER WEEK THAN THE FIRST WEEK OF JANUARY WITH
HIGHS MAINLY IN THE 40S AND 50S AND LOWS GENERALLY IN THE 30S.
79
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 56 43 48 41 49 / 10 80 100 70 30
WACO, TX 57 46 52 36 53 / 20 90 100 50 20
PARIS, TX 57 42 50 46 53 / 10 70 100 90 50
DENTON, TX 53 39 45 39 49 / 10 70 90 80 30
MCKINNEY, TX 55 42 49 41 49 / 10 70 100 80 40
DALLAS, TX 57 44 49 42 49 / 10 80 100 70 30
TERRELL, TX 55 45 52 42 52 / 10 80 100 80 30
CORSICANA, TX 59 49 56 40 52 / 20 90 100 70 30
TEMPLE, TX 58 46 51 38 56 / 20 90 100 40 20
MINERAL WELLS, TX 52 37 42 35 47 / 10 70 90 60 20
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
30/79
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
516 AM CST SUN JAN 8 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
215 AM CST SUN JAN 8 2012
MAIN FORECAST CONCERN IS HIGH TEMPERATURES MONDAY AND TUESDAY
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED RIDGING ALONG THE WEST COAST OF THE U.S. INTO SOUTHERN
ALBERTA...AN UPPER LOW OVER ARIZONA...A SHORTWAVE TROUGH OVER
EASTERN MONTANA AND BROAD TROUGHING OVER SOUTHEAST CANADA. LACK OF
ANY SIGNIFICANT FEATURES NEAR THE FORECAST AREA RESULTING IN DRY
CONDITIONS ALONG WITH CLEAR SKIES. WITH A SURFACE HIGH PRESSURE
RIDGE IN PLACE AND A DRY ATMOSPHERE SEEN ON THE 00Z DVN AND MPX
SOUNDINGS...TEMPERATURES HAVE FALLEN INTO THE TEENS AND
20S...COLDEST IN THE TYPICAL COLD SPOTS IN WISCONSIN. UPSTREAM...
THERE IS AN AREA OF MID CLOUDS CROSSING THE DAKOTAS AHEAD OF
MONTANA SHORTWAVE TROUGH. 850MB TEMPS ACROSS THE NORTHERN
PLAINS/UPPER MIDWEST HAVE HELD FAIRLY STEADY THE PAST 12
HOURS...AROUND -4C AT BIS...ABR AND MPX FOR THEIR 12Z SOUNDINGS
YESTERDAY AND 00Z SOUNDINGS TODAY.
TODAY AND TONIGHT...SHORTWAVE TROUGH SEEN OVER EASTERN MONTANA IS
PROGGED TO DIG SOUTH INTO THE CENTRAL PLAINS...IN RESPONSE TO THE
UPPER RIDGING OVER THE WESTERN U.S. BUILDING NORTHEAST TOWARDS THE
NORTHERN PLAINS. THE AREA OF MID CLOUDS AHEAD OF THIS SHORTWAVE
THROUGH APPEAR TO SCATTER OUT/DISSIPATE AS THEY COME INTO THE
FORECAST AREA THIS AFTERNOON...LIKELY DUE TO THE SHORTWAVE DIGGING
SOUTH VERSUS EAST. THEREFORE...ANTICIPATING A MOSTLY SUNNY DAY
TODAY. WITH 925MB TEMPS EXPECTED AROUND -2C AT 18Z...HIGHS SHOULD
END UP A FEW DEGREES WARMER THAN YESTERDAY. FOR TONIGHT...MODELS
ALSO PROG A SHORTWAVE TO RIDE ON TOP OF THE BUILDING RIDGING INTO
THE NORTHERN PLAINS...FORECAST TO DROP DOWN INTO NORTHWEST WISCONSIN
AT 12Z MONDAY. THIS SHORTWAVE SHOULD HAVE A WARM FRONT ASSOCIATED
WITH IT...CROSSING THE FORECAST AREA VERY LATE TONIGHT. THIS
FRONT...IN CONJUNCTION WITH A TIGHTENING PRESSURE GRADIENT...SHOULD
HELP TO AT LEAST STABILIZE THE TEMPERATURE FALL AND POSSIBLY START
BRINGING TEMPERATURES UP AROUND 12Z. WITH CLEAR/MOSTLY CLEAR SKIES
IN THE EVENING...LOWS SHOULD FALL INTO THE 20S. NOT ANTICIPATING
MUCH MORE THAN SOME MID/HIGH CLOUD TO ACCOMPANY THE WARM FRONT...SO
NO PRECIPITATION IS FORECAST.
MONDAY THROUGH TUESDAY NIGHT...THE UPPER RIDGING THAT WAS BUILDING
TOWARDS THE NORTHERN PLAINS TONIGHT IS PROGGED TO FLATTEN OUT AND
PUSH EAST...MOVING INTO THE FORECAST AREA FOR TUESDAY. THE FEATURE
RESPONSIBLE FOR THIS IS A POTENT SHORTWAVE TROUGH...EXPECTED TO DROP
DOWN THROUGH ALBERTA ON TUESDAY...THEN DIG INTO EASTERN MONTANA AND
THE WESTERN DAKOTAS BY 12Z WEDNESDAY. FOR OUR AREA...THE MAIN
CONCERN IS TEMPERATURES...WITH THE UPPER RIDGING BRINGING WITH IT A
SURGE OF PACIFIC AIR MODIFIED BY DOWNSLOPING OFF THE ROCKIES. 925MB
TEMPS CLIMB TO 0-2C FOR 18Z MONDAY AND 2-6C FOR 18Z TUESDAY. COOLEST
READINGS ARE NORTH OF I-94. THIS CLIMB IN TEMPERATURES IS
ACCOMPANIED BY WHAT SHOULD BE BREEZY WEST TO SOUTHWEST WINDS...NOTED
BY 925MB WINDS STAYING UP BETWEEN 20-35KT FOR THE ENTIRE TIME
PERIOD. AMOUNT OF SUNSHINE WILL BE CRITICAL IN DETERMINING HOW WARM
WE GET...GIVEN THE LACK OF SNOW COVER. LOOKS TO BE SOME MID/HIGH
CLOUDS AROUND MONDAY MORNING...BUT THESE SHOULD SCATTER/CLEAR OUT IN
THE AFTERNOON AS THE UPPER RIDGE FLATTENS. ANOTHER WAVE OF MID/HIGH
CLOUDS LOOKS TO COME THROUGH MONDAY NIGHT INTO TUESDAY MORNING...BUT
AGAIN CLEARING OUT FOR THE AFTERNOON. THEREFORE...PLENTY OF
SUN IS ANTICIPATED...ESPECIALLY TUESDAY FOR WARMING. PREVIOUS
FORECAST HIGHS FOR BOTH MONDAY AND TUESDAY LOOK VERY
REASONABLE...STAYING ON THE HIGH END OF GUIDANCE WHICH HAS WORKED
FOR THE RECENT ABOVE NORMAL STRETCH. POTENTIAL DEFINITELY EXISTS
TO BREAK SOME RECORD HIGHS. LOWS MONDAY NIGHT LIKELY TO STAY WELL
ABOVE NORMAL TOO...ESPECIALLY OVER HIGHER TERRAIN AREAS. FOR
TUESDAY NIGHT...A COLD FRONT WELL AHEAD OF THE POTENT UPPER TROUGH
LOOKS TO MOVE THROUGH THE AREA BETWEEN 06-12Z. SKIES SHOULD STAY
MOSTLY CLEAR...BUT COLD ADVECTION REALLY DOESNT GET GOING UNTIL
AFTER 12Z. THEREFORE HAVE STAYED ON THE WARM SIDE OF
GUIDANCE...ESPECIALLY GIVEN THE WARM TUESDAY.
.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT
215 AM CST SUN JAN 8 2012
MAIN FORECAST CONCERN AND UNCERTAINTY FOR THE LONG TERM FORECAST
CONTINUES TO REVOLVE AROUND THAT POTENT TROUGH APPROACHING THE
NORTHERN PLAINS 12Z WEDNESDAY. 08.00Z ECMWF/GFS/CANADIAN ALL SHOW
THE TROUGH DIGGING INTO THE NORTHERN PLAINS ON WEDNESDAY THEN
PUSHING EAST...BUT THE EXTENT OF THE DIGGING AND THE TIMING OF HOW
FAST IT MOVES EAST ARE BOTH IN QUESTION. THE ECMWF AND TO SOME
DEGREE THE CANADIAN ARE BY FAR THE DEEPEST...AND BOTH PRODUCE A
TROWAL AREA OF PRECIPITATION THAT CROSSES THE FORECAST AREA MOSTLY
WEDNESDAY NIGHT. THE GFS...BEING LESS AMPLIFIED AND MORE
PROGRESSIVE...KEEPS ANY TROWAL AREA OF PRECIPITATION NORTH OF THE
AREA. ALL SOLUTIONS AGREE ON PRETTY DRAMATIC COOLING...WITH 850MB
TEMPS DROPPING FROM 4-6C AT 12Z WEDNESDAY TO -12 TO -16C BY 12Z
THURSDAY AND POTENTIALLY NEAR -20C BY 00Z FRIDAY. FOR NOW...TO
HANDLE THE UNCERTAINTIES FOR WEDNESDAY THROUGH THURSDAY...HAVE
STAYED WITH THE CONSENSUS APPROACH FOR BOTH PRECIPITATION CHANCES
AND TEMPERATURES. ONE DISTINCT CHANGE IS THAT WEDNESDAY ENDS UP
WARMER...DUE TO THE COOLING WHICH HAS TRENDED SLOWER. WOULD NOT BE
SURPRISED IF WEDNESDAY MAY HAVE TO BE WARMED EVEN MORE.
THE PERIOD FOR THURSDAY NIGHT THROUGH SATURDAY NIGHT DOES NOT GET
ANY EASIER TO FORECAST...AGAIN RELATED TO HOW FAST THE POTENT TROUGH
CAN EXIT TO THE NORTHEAST. ONE THING FOR CERTAIN IS THAT THERE IS A
STRONG CONSENSUS FOR RIDGING TO BUILD OVER THE WESTERN U.S. INTO
SOUTHWEST CANADA DURING THIS TIME. HOW MUCH OF THIS SPREADS EAST
INTO THE FORECAST AREA IS UNKNOWN. THE 08.00Z GFS TRIES TO SPREAD
SOME RIDGING INTO THE FORECAST AREA LATE SATURDAY...BUT THE ECMWF
AND GFS ENSEMBLES WOULD PREFER TROUGHING TO STAY LOCKED IN PLACE.
THINK THE LATTER SCENARIO IS MORE LIKELY. THIS MEANS ONLY A SLOW
MODERATION IN TEMPERATURES. POTENTIAL WOULD EXIST FOR SOME
PRECIPITATION CHANCES WITH SHORTWAVES RIDING THROUGH THE NORTHWEST
FLOW ALOFT...AS INDICATED BY THE NEW 08.00Z ECMWF FOR SATURDAY.
HOWEVER...TIMING SOMETHING THAT FAR OUT IN THE FORECAST AND GIVEN
THE UNCERTAINTIES IN THE UPPER PATTERN...HAVE LEFT THE THURSDAY
NIGHT THROUGH SATURDAY NIGHT TIME PERIOD DRY.
&&
.AVIATION...TODAY AND TONIGHT
516 AM CST SUN JAN 8 2012
VFR CONDITIONS ARE EXPECTED AT THE TAF SITES THROUGH THE FORECAST
PERIOD. A WEAK UPPER LEVEL TROUGH WILL MOVE ACROSS THE REGION TODAY
BRINGING A FEW MID LEVEL CLOUDS TO THE TAF SITES...WITH CLOUD
BASES IN THE 8 TO 12 KFT RANGE. PLAN ON SOUTHWEST WINDS AT 5 TO 8
KTS TODAY. WINDS WILL GRADUALLY INCREASE TONIGHT AS A TROUGH MOVES
FROM THE NORTHERN PLAINS INTO THE GREAT LAKES. LOOK FOR SOUTHWEST
WINDS TO INCREASE INTO THE 10 TO 15 KT RANGE...MAINLY AFTER 06Z.
THE TROUGH WILL BRING A SCATTERED TO BROKEN CLOUD DECK ACROSS THE
TAF SITES WITH CLOUD BASES IN THE 8 TO 12 KFT RANGE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
215 AM CST SUN JAN 8 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....WETENKAMP
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
316 PM EST SUN JAN 8 2012
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE UPPER OHIO VALLEY AND ALLOW FOR
DRY AND MILD CONDITIONS THROUGH TUESDAY. A SURFACE LOW COMING FROM
THE SOUTHWEST WILL BRING RAIN TO THE AREA ON WEDNESDAY. MUCH
COLDER AIR IN THE WAKE OF THE LOW WILL BRING SNOW SHOWERS FOR THE
END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE LATEST RUC MID-LEVEL ANALYSIS INDICATES A ZONAL FLOW ACROSS THE
UPPER OHIO VALLEY WITH AN AREA OF MID-LEVEL MOISTURE UPSTREAM
MOVING INTO WESTERN OHIO. AT THE SURFACE, OBS/MSAS INDICATE A 1027MB
HIGH CENTERED ACROSS ILLINOIS. THIS BROAD AREA OF HIGH PRESSURE
EXTENDS FROM THE CENTRALS PLAINS ACROSS THE UPPER OHIO VALLEY AND
INTO THE MID-ATLANTIC. IN A NORTHWESTERLY FLOW, THE MOISTURE FEED
OFF OF LAKE ERIE IS PROVIDING STRATOCUMULUS CLOUD COVERAGE FOR
AREAS MOSTLY NORTH AND EAST OF PITTSBURGH.
TONIGHT...HIGH PRESSURE WILL SLIDE ACROSS THE AREA, ALLOWING FOR DRY
CONDITIONS TO CONTINUE. 850MB FLOW SHIFTING TO ZONAL WILL ALLOW
FOR DRIER LOW-LEVEL AIR TO PUSH ACROSS THE AREA. ALTHOUGH LOW-
LEVEL CLOUDS WILL DIMINISH ACROSS THE AREA WITH CLEARING BY THIS
EVENING, MID- LEVEL MOISTURE WILL THEN BEGIN TO ADVECT IN FROM THE
WEST. THUS, MOSTLY CLOUDY IS THE FORECAST OVERNIGHT. DESPITE TDS
IN THE LOW 20S AND HIGH PRESSURE OVERHEAD TONIGHT, MID-LEVEL CLOUD
COVERAGE WILL SERVE TO LIMIT RADIATIONAL COOLING. OVERNIGHT LOWS
WILL RANGE FROM THE LOWER 20S ACROSS THE EASTERN RIDGES TO THE
UPPER 20S SOUTH OF THE I-70 CORRIDOR.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
THERE IS HIGH CONFIDENCE WITH OPERATIONAL MODEL AGREEMENT THAT AN
INITIAL SURFACE HIGH WILL SHIFT EAST OF THE AREA EARLY ON MONDAY.
THE DRY PATTERN WILL THEN BE REINFORCED BY ANOTHER HIGH BUILDING IN
FROM THE CENTRAL PLAINS. THIS WILL ALLOW FOR A RELATIVELY BENIGN AND
WARM SPELL TO CONTINUE FOR MONDAY AND TUESDAY. ASIDE FROM SOME
PASSING MID-LEVEL CLOUDS, MOSTLY SUNNY SKIES FOR THE MAJORITY CAN BE
EXPECTED THROUGH THIS PERIOD.
HIGH TEMPERATURES MONDAY AND TUESDAY ARE GENERALLY 2-4 DEGREES
WARMER THAN A MAV/MET BLEND. HIGHS ON MONDAY WILL RANGE FROM THE
THE LOWER 40S ACROSS THE I-80 CORRIDOR AND EASTERN RIDGES TO THE
LOWER 50S IN NORTH-CENTRAL WV AND PORTIONS OF EASTERN OHIO. WITH
WEAK WARM AIR ADVECTION, EXPECT TEMPS ON TUESDAY TO BE A COUPLE
DEGREES WARMER THAN MONDAY. OVERNIGHT LOWS WILL BE AROUND 5 TO 10
DEGREES ABOVE SEASONAL NORMALS.
WEDNESDAY...MODELS BEGIN TO DIFFER IN TIMING THE ONSET OF THE
NEXT RAIN EVENT. FORECAST IS CLOSEST TO THE SLIGHTLY FASTER GFS.
A CLOSED MID-LEVEL LOW ACROSS THE CENTRAL GULF STATES WILL MOVE
ACROSS THE TENNESSEE VALLEY. 12Z OPERATIONAL MODEL RUNS HAVE SLOWED
ONSET OF PRECIP ALTHOUGH FORECAST ONLY TRENDS THIS WAY SLIGHTLY TO
AVOID A DRASTIC CHANGE AT THIS POINT. FORECAST REFLECTS AN AREA OF
ISENTROPIC LIFT BRINGING SHOWERS TO THE AREA EARLY ON WEDNESDAY.
THUS, CHANCE POPS BEGIN AFTER 12Z WED AND RAMP UP TO LIKELY BY
WEDNESDAY AFTERNOON. WITH A WARM FRONT PUSHING NORTHWARD INTO THE
AREA, TEMPERATURES WILL BE AROUND 15 DEGREES ABOVE NORMAL,
REACHING THE 50S ACROSS MOST LOCATIONS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
RAIN WILL BE LIKELY ACROSS THE REGION WEDNESDAY NIGHT AS STRONG
SURFACE LOW MOVES ACROSS THE MID ATLANTIC STATES AND TO THE COAST BY
THURSDAY MORNING. ON THURSDAY QUITE STRONG NORTHERN BRANCH CLOSED
UPPER LOW DIGS ACROSS THE GREAT LAKES. THIS NORTHERN BRANCH LOW WILL
BRING MUCH COLDER AIR INTO REGION STARTING THURSDAY AFTERNOON AND
CONTINUING INTO THE WEEKEND. RAIN SHOWERS WILL MIX WITH AND CHANGE
TO SNOW THURSDAY FOLLOWED BY NORTHWEST FLOW SNOW SHOWERS INTO
SATURDAY. A RIDGE OF HIGH PRESSURE WILL BRING DRY AIR AND DIMINISH
SNOW SHOWERS SUNDAY. AFTER A MILD START WEDNESDAY NIGHT INTO EARLY
THURSDAY TEMPERATURES WILL AVERAGE 5 TO 10 DEGREES BELOW NORMAL.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
VFR INTO MONDAY WITH LEFTOVER STRATUS FROM LAKES ERODING THIS
EVENING TO BE REPLACED BY MID DECK APPROACHING FROM THE LOWER OHIO
VALLEY LATER TONIGHT. LIGHT NORTH WINDS THIS EVENING WILL TRANSITION
TO LIGHT SOUTH TO SOUTHWEST MONDAY.
OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
VFR INTO EARLY WEDNESDAY. NORTHEASTBOUND LOW PRESSURE FROM LOUISIANA
WILL PROVIDE RESTRICTIONS IN RAIN LATER WEDNESDAY INTO EARLY
THURSDAY. RAIN SHOWERS WILL MIX AND CHANGE TO SNOW SHOWERS THURSDAY
WITH RESTRICTIONS IN SNOW SHOWERS THROUGH FRIDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1255 PM EST SUN JAN 8 2012
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE UPPER OHIO VALLEY AND ALLOW FOR
DRY AND MILD CONDITIONS THROUGH TUESDAY. A SURFACE LOW COMING FROM
THE SOUTHWEST WILL BRING RAIN TO THE AREA ON WEDNESDAY. MUCH
COLDER AIR IN THE WAKE OF THE LOW WILL BRING SNOW SHOWERS FOR THE
END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
18Z ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED TO TIME
THE DIMINISHING OF STRATOCUMULUS NORTH OF I-70 AND CLEARING IN
EASTERN OHIO. OTHERWISE, REST OF PREVIOUS DISCUSSION REMAINS THE
SAME.
THE LATEST RUC MID-LEVEL ANALYSIS INDICATES A ZONAL FLOW ACROSS
THE UPPER OHIO VALLEY WITH AN AREA OF MID-LEVEL MOISTURE UPSTREAM
IN THE MISSOURI VALLEY. AT THE SURFACE, OBS/MSAS INDICATE A 1029MB
HIGH CENTERED ACROSS ILLINOIS. THIS BROAD AREA OF HIGH PRESSURE
EXTENDS FROM THE CENTRALS PLAINS ACROSS THE UPPER OHIO VALLEY AND
INTO THE MID-ATLANTIC. 12Z SOUNDING INDICATES SUBSIDENCE ABOVE
850MB WITH THE DRY WEATHER PATTERN CONTINUING. IN A NORTHWESTERLY
FLOW, MOISTURE FEED OFF OF LAKE ERIE IS PROVIDING STRATOCUMULUS
CLOUD COVERAGE THIS AFTERNOON.
THIS AFTERNOON AND TONIGHT...HIGH PRESSURE WILL SLIDE ACROSS THE
AREA, ALLOWING FOR DRY CONDITIONS TO CONTINUE. 850MB NORTHWESTERLY
FLOW WILL BRING MOSTLY CLOUDY SKIES TO AREAS NORTH AND EAST OF
PITTSBURGH. FLOW WILL BECOME ZONAL, WITH DRIER LOW-LEVEL AIR
ADVECTING INTO THE AREA. ALTHOUGH LOW-LEVEL CLOUDS WILL DIMINISH
ACROSS THE AREA BY THIS EVENING, BY THAT TIME, MID-LEVEL MOISTURE
WILL BEGIN TO ADVECT ACROSS THE AREA. THUS, MOSTLY CLOUDY IS THE
FORECAST OVERNIGHT.
FOR TEMPERATURES, HIGHS TODAY ARE A FEW DEGREES WARMER THAN LAMP
GUIDANCE. HIGHS WILL RANGE FROM THE MID 30S ALONG THE I-80
CORRIDOR TO THE MID 40S IN PORTIONS OF EASTERN OHIO AND NORTH-
CENTRAL WV. DESPITE TDS IN THE LOW 20S AND HIGH PRESSURE OVERHEAD
TONIGHT, MID-LEVEL CLOUD COVERAGE WILL SERVE TO LIMIT RADIATIONAL
COOLING. OVERNIGHT LOWS WILL RANGE FROM THE LOWER 20S ACROSS THE
EASTERN RIDGES TO UPPER 20S SOUTH OF THE I-70 CORRIDOR.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
HIGH PRESSURE WILL PROVIDE DRY WEATHER AND MILD TEMPERATURES
THROUGH THIS PERIOD.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
A CLOSED MID-LEVEL LOW WILL MOVE FROM THE WESTERN GULF STATES ACROSS
THE TENNESSEE VALLEY TUESDAY NIGHT INTO WEDNESDAY. THE CHANCE OF
RAIN WILL ARRIVE LATE TUESDAY NIGHT AS A WARM FRONT AHEAD OF THE LOW
PUSHES NORTHWARD INTO THE AREA. MODEL THICKNESSES WILL WARM ABOVE
CRITICAL THRESHOLDS THAT WOULD BE NEEDED FOR A WINTRY MIX, SO
FORECAST IS FOR ALL RAIN TO BEGIN THE EVENT. TEMPERATURES WILL BE
AROUND 10 DEGREES ABOVE NORMAL THROUGH THE MID-WEEK.
RAIN WILL BE LIKELY ACROSS THE REGION WEDNESDAY INTO WEDNESDAY NIGHT
AS THE LOW MOVES ACROSS WEST VIRGINIA AND INTO THE NORTHEAST. BY
THURSDAY MORNING LOW WILL BE EXITING EAST AS QUITE STRONG NORTHERN
BRANCH CLOSED UPPER LOW DIGS ACROSS THE GREAT LAKES. THIS NORTHERN
BRANCH LOW WILL BRING MUCH COLDER AIR INTO REGION STARTING THURSDAY
AND CONTINUING INTO THE START OF THE WEEKEND. RAIN SHOWERS WILL MIX
WITH AND CHANGE TO SNOW THURSDAY FOLLOWED BY NORTHWEST FLOW SNOW
SHOWERS INTO FRIDAY. BY SATURDAY A RIDGE OF HIGH PRESSURE WILL BRING
DRY AND COLD CONDITIONS. AS ALSO SUPPORTED BY NAEFS MEDIAN VALUES
TEMPERATURES WILL FALL TO 5 TO 10 DEGREES BELOW NORMAL LATE WEEK.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
VFR REMAINDER OF DAY AS DECK OF BKN-OVC SC WILL CONTINUE TO SHIFT
EAST WITH MID-LEVEL COLD POOL. CLOUDS WILL ERODE BY LATE AFTERNOON
AS WAA BEGINS.
OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...
VFR INTO TUESDAY NIGHT. NORTHEASTBOUND LOW PRESSURE FROM LOUISIANA
WILL PROVIDE MIXED PRECIPITATION AND RESTRICTIONS WEDNESDAY AND
THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
354 PM EST SUN JAN 8 2012
.SYNOPSIS...
WV IMAGERY AND RUC ANALYSIS INDICATED MID/UPPER LEVEL RIDGE OVER THE
WEST COAST INTO BC/ALBERTA LEAVING WNW FLOW DOWNSTREAM THROUGH SRN
CANADA INTO THE NRN GREAT LAKES. A WEAK SHORTWAVE TROUGH FROM NEAR
THE SW END OF HUDSON BAY TO LAKE SUPERIOR THAT SUPPORTED BAND OF
SNOW SHOWERS ACROSS LAKE SUPERIOR AND NRN UPPER MI WAS EXITING TO
THE EAST. THE NEXT SIGNIFICANT SHRTWV WAS LOCATED OVER NRN MANITOBA.
AT THE SFC...WINDS WERE BACKING W AND SW AS A RIDGE BUILDS TOWARD
THE AREA. THE VIS SATELLITE LOOP SHOWED CLEARING OVER THE SW HALF OF
THE CWA AS DRIER AIR IN THE SFC-850 MB LAYER MOVES IN FROM THE
WEST.
&&
.SHORT TERM...TONIGHT AND MONDAY
THE NRN MANITOBA SHRTWV IS EXPECTED TO DIVE SOUTHEASTWARD TOWARD THE
UPPER GREAT LAKES. A BAND OF MODERATE 700-300 QVECTOR CONV WILL
SPREAD ACROSS THE AREA ALONG WITH A BAND OF FAIRLY STRONG 285K-290K
ISENTROPIC ASCENT FROM 09Z-15Z. HOWEVER...WITH LITTLE MOISTURE
AVBL...THE SFC-850 MB LAYER REMAINS RELATIVELY DRY. THE PATH OF THE
SHRTWV AND MODELS CONSENSUS STRONGEST FORCING AND QPF SUGGEST THAT
THE NORTH AND EAST PORTIONS OF THE CWA HAVE THE BEST CHANCE OF
SEEING SOME LIGHT SNOW. HOWEVER...ANY AMOUNTS ARE EXPECTED TO BE
LIGHT...GENERALLY A HALF INCH OR LESS. LEFTOVER CLOUDS INTO THE
EARLY AFTERNOON MAY DELAY WARMING ENOUGH TO KEEP TEMPS MAINLY
IN THE MID TO UPPER 30S...ESPECIALLY OVER THE EAST.
.LONG TERM /00Z TUE THROUGH NEXT SUN/...
EXPECT WARMER CONDITIONS MONDAY NIGHT AND TUESDAY AS THE UPPER GREAT
LAKES REMAINS IN WARM SECTOR OF LOW PRESSURE SYSTEM SLIDING FROM
MANITOBA INTO ONTARIO. BROKEN MID CLOUDS SHOULD BE AROUND LATE
MONDAY NIGHT INTO TUESDAY MORNING...BUT SOME SUNSHINE SHOULD APPEAR
BY AFTERNOON. GIVEN THE SUNSHINE AND SW WINDS AT THE SFC...TUESDAY
COULD BE ANOTHER DAY WITH NEAR RECORD OR RECORD WARMTH. MIXING TO
950-925MB SUPPORTS HIGHS AOA 40 DEGREES FOR MANY AREAS. KEPT THE
TREND FROM THE PREVIOUS SHIFT TOWARD HIGH END OF BIAS CORRECTED
GUIDANCE WHICH RESULTED IN MAX TEMPS IN MID TO UPPER 40S TOWARD WI
BORDER WHERE SNOW COVER REMAINS PRETTY THIN. RECORD HIGH AT NWS
MARQUETTE FOR TUESDAY IS 42 SET IN 2001. THIS IS EXPECTED TO BE THE
LAST WARMER DAY AT LEAST THROUGH NEXT WEEKEND AS PATTERN BEGINS TO
CHANGE ON WEDNESDAY.
WED THROUGH FRI...MODEL AGREEMENT HAS IMPROVED SINCE YESTERDAY WITH
A STRONG LOW PRESSURE SYSTEM THAT IS SET TO MOVE OVER THE AREA WED
THROUGH FRI. COMPARING THE 12Z/08 GFS...00Z/08 ECMWF...AND
12Z/08 GEM SOLUTIONS...THE GEM IS MORE OF AN OUTLIER SO IT WAS RULED
OUT FOR THIS FORECAST. BOTH THE GFS AND ECMWF BRING A 500MB TROUGH
FROM A CLOSED LOW FROM OVER AK...SHOWING A LOW CLOSING OFF FROM THE
TIP OF THE TROUGH AS IT MOVES INTO THE PACIFIC NW. MODELS THEN
DEPICT THE TROUGH MOVING TOWARD THE CWA BEFORE DEEPENING JUST
UPSTREAM OF THE CWA IN RESPONSE TO JET INTERACTION. THE GFS DEEPENS
THE UPPER TROUGH INTO A CLOSED LOW FASTER THAN THE ECWMF...AND IS
MORE TRANSIENT WITH THE SYSTEM AS IT MOVES S OF THE CWA. THE ECMWF
KEEP AN OPEN WAVE ALOFT UNTIL IT MOVES INTO WI AROUND 00Z FRI...AND
IS ABOUT 12 HOURS SLOWER WITH MOVING THE SYSTEM OUT THAN THE GFS.
THERE IS STILL FAIR POTENTIAL THAT MODELS ARE NOT SETTLED WITH THEIR
SOLUTIONS YET. A BIG REASON MODELS DIVERGE WITH THE TRACK AND
INTENSITY OF THE SYSTEM STARTS BACK WHEN THE TROUGH IS MOVING INTO
THE PACIFIC NW. A LOT WILL DEPEND OF WHAT MODELS DO WITH THE LOW
THAT IS SHOWN BREAKING OFF OF THE TROUGH. MODELS CURRENTLY AGREE
PRETTY WELL THAT THE LOW WILL STAY OFF THE CA COAST FOR A WHILE. IF
THE LOW MOVES FARTHER EAST FASTER...OR DEVELOPS FARTHER EAST...IT
WILL CUTS OFF SOME ACCESS TO COMPONENTS OF BOTH THE NRN AND SRN
STREAM JETS...CAUSING THE MAIN SYSTEM NOT TO STRENGTHEN AS MUCH AND
PROBABLY STAY FARTHER N. HOWEVER...EVEN IF THIS HAPPENS...850MB
TEMPS SHOULD STILL FALL TO AROUND -20C OVER LAKE SUPERIOR. WITH THE
SFC LOW DEEPENING OVER THE LOWER GREAT LAKES...NW BOUNDARY LAYER
WINDS LOOK TO BE THE WAY TO GO...AND THIS IS AGREED UPON WELL BY
MODELS. LIKELY POPS ARE WELL JUSTIFIED AT THIS POINT IN AREAS
FAVORED BY NW FLOW OFF LAKE SUPERIOR. CURRENTLY MODEL CONSENSUS
WOULD ALSO LEAD TO SYNOPTIC SNOW OVER THE REST OF UPPER MI...BUT
THIS IS A LITTLE MORE UNCERTAIN DUE TO UNCERTAINTY IN THE EXACT
TRACK OF THE UPPER LOW. WILL CONTINUE TO HIGHLIGHT THIS POTENTIAL
HEAVY SNOW IN THE HAZARDOUS WEATHER OUTLOOK.
SAT AND SUN...DID NOT DWELL TOO MUCH ON THIS PERIOD DUE TO
INCREASING MODEL VARIABILITY...BUT MODELS CURRENTLY SHOW SLIGHTLY
WARMER 850MB TEMPS STILL COLD ENOUGH FOR LES WITH A GENERALLY NW
WIND...AND A COUPLE OF SHORTWAVES MOVING THROUGH. THIS WOULD LEAD TO
PERIODS OF LES AND SLIGHTLY WARMER...BUT NEAR SEASONAL...TEMPS.
STAYED WITH CONSENSUS MODEL BLEND GIVEN UNCERTAINTY.
&&
.AVIATION /FOR THE 18Z TAF ISSUANCE/...
AS A WEAK TROUGH EXITS THE AREA AND HIGH PRES BUILDS TOWARD THE
AREA...EXPECT REMAINING MVFR CIGS AT KCMX TO LIFT BY MID AFTERNOON.
EXPECT VFR CONDITIONS FOR THE REST OF THE FCST PERIOD. LOW LVL WIND
SHEAR WILL DEVELOP LATER THIS EVENING AND OVERNIGHT AS SW GRAD
TIGHTENS AHEAD OF LOW PRESSURE SYSTEM MOVING ACROSS NRN ONTARIO AS A
LOW-LVL WIND MAX MOVES ACROSS THE AREA. BY MON MORNING...GUSTY
SOUTHWEST TO WEST SOUTHWEST ARE EXPECTED.
&&
.MARINE /FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE/...
LOW PRESSURE IS FORECAST TO MOVE FROM ALBERTA TO JAMES BAY BY
MONDAY. STRONG PRESSURE FALLS NORTH OF LAKE SUPERIOR AND AN
INCREASING PRESSURE GRADIENT IS EXPECTED TO RESULT IN GALE FORCE
SOUTHWEST WINDS OVER MUCH OF LAKE SUPERIOR LATE TONIGHT INTO MONDAY
WITH GALE WINDS SHIFTING WEST ON MONDAY AFTERNOON OVER ERN LAKE
SUPERIOR BEFORE DIMINISHING BLO GALES MON EVENING. WINDS WILL
DIMINISH BY TUESDAY WITH A WEAKENING PRESSURE GRADIENT...BUT WILL
INCREASE OUT OF THE N-NW WEDNESDAY NIGHT INTO FRIDAY AS MUCH COLDER
SPREADS ACROSS THE REGION AND THE PRES GRADIENT TIGHTENS IN THE WAKE
OF A DEEPENING LOW PRESSURE SYSTEM. N/NW WINDS SHOULD REACH GALE OR
NEAR GALE FORCE LATE WED NIGHT INTO FRI MORNING WITH MODERATE HEAVY
FREEZING SPRAY THU NIGHT INTO FRI.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 5 AM TO 4 PM EST MONDAY FOR LSZ267.
GALE WARNING FROM 3 AM TO 7 PM EST MONDAY FOR LSZ266.
GALE WARNING FROM 1 AM EST /MIDNIGHT CST/ TO 11 AM EST /10 AM
CST/ MONDAY FOR LSZ162.
GALE WARNING FROM 1 AM TO 3 PM EST MONDAY FOR LSZ263-264.
GALE WARNING FROM 7 AM TO 7 PM EST MONDAY FOR LSZ265.
GALE WATCH FROM MONDAY MORNING THROUGH MONDAY AFTERNOON FOR
LSZ243-244.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS RALEIGH NC
118 PM EST SUN JAN 8 2012
.SYNOPSIS...
A COLD FRONT WILL STALL JUST SOUTH OF THE AREA TODAY. WEAK WAVES OF
LOW PRESSURE WILL DEVELOP ALONG THE FRONT TONIGHT INTO MONDAY...
RESULTING IN COOL AND DAMP CONDITIONS. DRY HIGH PRESSURE WILL RETURN
ON TUESDAY...FOLLOWED BY A POTENT STORM SYSTEM EXPECTED TO TRACK
ACROSS THE CAROLINAS ON WEDNESDAY.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 952 AM SUNDAY...
FOR THE REST OF TODAY: LATEST OBSERVED WEATHER TRENDS REMAIN IN LINE
WITH THE EARLIER FORECAST. THE MOST RECENT SURFACE ANALYSES SHOW THE
COLD FRONT MAKING SLOW BUT STEADY SOUTHWARD PROGRESS THROUGH THE FAR
SOUTHERN CWA... WHILE SPRAWLING HIGH PRESSURE CENTERED OVER IL (AND
STRETCHING FROM THE HEARTLAND ACROSS THE MIDATLANTIC) ATTEMPTS TO
BUILD INTO CENTRAL NC. WHILE THE PATCHY LIGHT RAIN FROM EARLY THIS
MORNING HAS DISSIPATED AND EXITED... A BROKEN DECK OF CLOUDS
CONTINUES TO PUSH SLOWLY EASTWARD INTO OUR AREA... HAVING OVERSPREAD
ALL BUT THE EASTERN CWA THUS FAR. PATCHY SPRINKLES FORCED BY MASS
CONVERGENCE NEAR THE LOW LEVEL FRONTAL ZONE WILL REMAIN A
POSSIBILITY OVER THE SOUTHWEST AND SOUTHERN CWA FOR THE NEXT SEVERAL
HOURS... SO HAVE SLIGHTLY SPED UP THE TIMING OF PRECIP ARRIVAL HERE
BY A COUPLE OF HOURS. THIS INITIAL PRECIP SHOULD REMAIN VERY LIGHT
GIVEN THE LACK OF ANY STRONG LIFT AND THE SHALLOW NATURE OF THE
INCOMING MOIST ISENTROPIC UPGLIDE. A BETTER CHANCE OF RAIN WILL
ARRIVE AFTER 4 PM THIS AFTERNOON AS THE UPGLIDE-SUPPORTED PRECIP NOW
OVER TN/AL/GA -- ENHANCED BY A WEAK SURFACE LOW ALONG THE FRONT --
SPREADS INTO CENTRAL NC. BOTH EXTRAPOLATION AND RECENT HRRR RUNS
SUPPORT THIS TIMING. AFTERNOON TEMP RISE WILL BE LESS THAN TYPICAL
GIVEN THE INCOMING CLOUDS AND LOW LEVEL COLD AIR ADVECTION...
HOWEVER THIS ADVECTION WILL BE QUITE WEAK AND WE STILL ANTICIPATE
POCKETS OF SUNSHINE THIS AFTERNOON. HAVE NUDGED HIGHS UP A BIT TO
55-62. -GIH
TONIGHT:
THE 00Z GFS/NAM/ECMWF ALL SHOW ISENTROPIC LIFT STRENGTHENING OVER
THE AREA TONIGHT FROM THE SOUTHWEST AS THE AFOREMENTIONED LOW-LEVEL
RIDGE PROGRESSES SLOWLY EASTWARD TO THE BAHAMAS...RESULTING IN A
MORE FAVORABLE LOW-LEVEL GULF RETURN FLOW OVER THE CAROLINAS THAT
WILL OVERRUN THE COOL/DRY AIRMASS DEPOSITED IN THE WAKE OF THE
BACKDOOR COLD FRONT THIS MORNING. ALL OF THE MODEL GUIDANCE SHOWS A
TRACE TO SEVERAL HUNDREDTHS OF AN INCH OF RAIN ACROSS THE AREA
OVERNIGHT...ALTHOUGH JUST HOW WIDESPREAD PRECIPITATION WILL BE
REMAINS IN QUESTION. WILL CONTINUE TO SHOW A 50% CHANCE OF RAIN OVER
THE ENTIRE AREA OVERNIGHT...WITH PRECIPITATION AMOUNTS GENERALLY A
FEW HUNDREDTHS OF AN INCH OR LESS (NAM/ECMWF). THE GFS REMAINS AN
OUTLIER...SHOWING 0.10-0.15". LOWS TONIGHT WILL HIGHLY DEPEND ON
WHERE AND HOW MUCH PRECIPITATION OCCURS. WHERE PRECIP DOES OCCUR...
GIVEN THE COOL/DRY SURFACE AIRMASS IN PLACE...A HYBRID CAD WEDGE
WILL DEVELOP...AND EVAP COOLING WOULD KEEPS TEMPS A FEW DEGREES
LOWER THAN AREAS WITHOUT PRECIP. GIVEN THE AFOREMENTIONED
UNCERTAINTY...AT THIS TIME WILL CONTINUE TO FOLLOW MOS GUIDANCE...
WITH LOWS RANGING FROM THE UPPER 30S IN THE NORTH TO LOWER 40S IN
THE SOUTH. -VINCENT
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
AS OF 330 AM SUNDAY...
MONDAY:
THE WEAKENING SHEAR AXIS EXTENDING ENE FROM THE CENTRAL PLAINS INTO
NEW ENGLAND BY 12Z MONDAY IS PROGGED TO CONTINUE WEAKENING AS IT
PROGRESSES EAST OR ESE TOWARD THE MID-ATLANTIC ON MONDAY. THE
AFOREMENTIONED SHORTWAVE DIGGING SOUTHEAST INTO THE UPPER GREAT
LAKES BY 12Z MON IS PROGGED TO DIG INTO THE LOWER GREAT LAKES BY 00Z
TUESDAY...AND IS GENERALLY EXPECTED TO REMAIN TOO FAR NORTH TO HAVE
MUCH INFLUENCE ON CENTRAL NC DURING THE DAY MON. HOWEVER...THE SHEAR
AXIS (AND AN ASSOCIATED WEAK LOW-LEVEL TROUGH) PROGRESSING TOWARD
THE AREA SHOULD PROVIDE SUFFICIENT FORCING FOR PRECIPITATION VIA A
COMBINATION OF DPVA AND LOW/MID LEVEL ISENTROPIC LIFT. EXPECT PATCHY
DRIZZLE/LIGHT RAIN TO BE ONGOING MONDAY MORNING IN ASSOC/W
RELATIVELY WEAK ISENTROPIC LIFT...AND WILL CONTINUE TO SHOW A 50%
CHANCE OF RAIN EVERYWHERE THROUGH NOON. AFTER NOON...THE BETTER
FORCING MENTIONED ABOVE WILL ARRIVE...AND WILL INCREASE POPS TO
LIKELY (60%) GIVEN THAT MOST OF THE MODEL GUIDANCE (NAM/ECMWF) SHOWS
MEASURABLE PRECIP OVER CENTRAL NC MONDAY AFTERNOON (GFS AN OUTLIER
WITH BARELY MORE THAN A TRACE)...WITH ADDITIONAL SUPPORT FROM THE
NCEP HIGH-RES WRF-NMM WHICH SHOWS A WIDESPREAD SWATH OF RAIN
CROSSING CENTRAL NC FROM WEST-EAST BETWEEN ROUGHLY 18-00Z. HIGHS ON
MONDAY ARE DIFFICULT TO ASCERTAIN GIVEN SOME QUESTION WITH THE
LOCATION/EXTENT OF RAIN/DRIZZLE PRIOR EARLY IN THE DAY PRIOR TO THE
MORE WIDESPREAD RAIN EXPECTED IN THE AFTERNOON. REGARDLESS...EXPECT
A HYBRID OR IN-SITU CAD WEDGE TO DEVELOP...WITH HIGHS COOLER THAN IN
PREVIOUS DAYS. WILL INDICATE HIGHS RANGING FROM THE UPPER 40S N/NW
PIEDMONT TO LOWER 50S ELSEWHERE. IT IS POSSIBLE THAT HIGHS MAY NOT
EXCEED THE MID/UPPER 40S IF DRIZZLE OR LIGHT RAIN IS PREVALENT
THROUGH THE MORNING AND EARLY AFTERNOON HOURS PRIOR TO THE POTENTIAL
FOR MORE WIDESPREAD RAIN MOVING ACROSS THE AREA FROM WEST-EAST
MID/LATE AFTERNOON.
MONDAY NIGHT:
PRECIP ASSOC/W THE SHEAR AXIS AND RESULTING LOW/MID LEVEL ISENTROPIC
LIFT MON AFTERNOON SHOULD END BY 00-03Z TUE AS THE SHEAR AXIS
PROGRESSES OFFSHORE. THE AFOREMENTIONED H5 SHORTWAVE DIGGING INTO
THE LOWER GREAT LAKES DURING THE DAY MONDAY IS PROGGED TO AMPLIFY AS
IT DIGS INTO NEW ENGLAND AND THE MID-ATLANTIC BY 06Z TUE...FURTHER
AMPLIFYING AS IT PROGRESSES OFFSHORE THE MID-ATLANTIC BETWEEN
06-12Z. THIS AMPLIFYING UPPER LEVEL TROUGH WILL INITIATE
CYCLOGENESIS OFFSHORE THE CAROLINA COAST MON NIGHT AND RESULT IN A
FORMIDABLE EXTRATROPICAL CYCLONE IN THE NORTH ATLANTIC DURING THE
DAY TUE. OVER CENTRAL NC...HEIGHT/RISES SYNOPTIC SUBSIDENCE IN THE
WAKE OF THE SHEAR AXIS AND UPPER LEVEL TROUGH WILL RAPIDLY WARM/DRY
THE MID AND UPPER LEVELS AFTER 00-03Z TUE...IN ADDITION TO PRESSURE
RISES UPSTREAM IN THE OH VALLEY AND MID-ATLANTIC WHICH SHOULD HELP
FORCE A DRIER LOW-LEVEL AIRMASS INTO THE AREA BY 12Z TUE. IT IS
STILL NOT CLEAR WHETHER OR NOT THE CAD WEDGE WILL ENTIRELY SCOUR OUT
BY SUNRISE TUE. MODEL SOUNDINGS CONTINUE TO SHOW A VERY SHALLOW
SATURATED LAYER PERSISTING THROUGH 12Z TUE...AND HIGH PRESSURE
UPSTREAM OF THE AREA MAY NOT BE STRONG ENOUGH TO RESULT IN
APPRECIABLE SURFACE COLD ADVECTION TO COMPLETELY SCOUR OUT THE
WEDGE. WITH THE ABOVE IN MIND...UNCERTAINTY PERSISTS W/REGARD TO
CLOUD COVER AND LOW TEMPS. WILL SHOW AT LEAST A CLEARING TREND...
WITH LOWS RANGING FROM THE UPPER 30S TO LOWER 40S. -VINCENT
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 245 AM SUNDAY...
THE EJECTION OF THE MID-UPPER LOW FROM THE SOUTHWEST IS THE MAIN
WEATHER FEATURE TO WATCH THIS PERIOD... ALONG WITH A TURN TO COLDER
CONDITIONS LATE IN THE WEEK AND NEXT WEEKEND. OUT AHEAD OF THIS
STORM... IT WILL BECOME VERY MILD TO WARM AGAIN WITH TEMPERATURES
AVERAGING 10-15 DEGREES ABOVE THE 30 YEAR NORMALS.
THE MID-UPPER LOW IS ALREADY CUT OFF FROM THE MAIN WESTERLIES AND
THIS FAVORS THE MORE SOUTHERN AND SLOWER FORECASTS THAT THE NEW
EUROPEAN MODEL SUITE INDICATES. HOWEVER... NEARLY ALL MODEL GUIDANCE
INDICATES A FAIRLY SIMILAR SYSTEM WILL AFFECT OUR REGION CENTERED
AROUND WED-WED NIGHT... BUT THE TRACK IS OF CONCERN AS SOME MODELS
TRACK THE MID LEVEL CIRCULATION OVERHEAD... SOME TO OUR NW AND SOME
TO OUR SE. THE EXACT TRACK WILL DICTATE MANY ASPECTS OF THE SYSTEM
FOR OUR REGION... INCLUDING QPF/THUNDER CHANCES/TEMPS. FOR NOW... WE
WILL MAINTAIN OUR CURRENT FORECASTS... AND INCORPORATE A SLIGHTLY
SLOWER AND EVEN MORE MOIST SYSTEM PER THE LATEST EUROPEAN MODEL. IN
ADDITION... IF THE EUROPEAN TRACK VERIFIES... WE WOULD GE A
SIGNIFICANT RAIN WITH 1 TO 1.5 INCHES ACROSS THE REGION.
AFTER THE SYSTEM PASSES... IT WILL TURN COLDER... BUT REALLY NOT
UNTIL FRIDAY WHEN THE MAIN PUSH OF CAA IS EXPECTED. THERE IS STILL
QUITE A BIT OF DIFFERENCES IN THE MODEL FORECASTS AFTER FRIDAY WITH
THE CANADIAN INDICATING ANOTHER SOUTHERN BRANCH SYSTEM. MORE ON THIS
LATER.
SENSIBLE WEATHER HIGHLIGHTS... TUESDAY... SOME MORNING DRIZZLE...
BECOMING PARTLY CLOUDY AND WARMING INTO THE 60S. WEDNESDAY...
PERIODS OF RAIN WITH HIGHS 55-65. THURSDAY... RAIN ENDING. PARTLY
CLOUDY. HIGHS IN THE 60S. FRIDAY... TURNING COLDER AND BREEZY. HIGHS
IN THE 50S.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
AS OF 118 PM SUNDAY...
24-HR TAF PERIOD:
VFR CONDITIONS WITH CEILINGS IN THE 4-7 KFT RANGE ARE EXPECTED TO
PREDOMINATE THROUGH ~00Z THIS EVENING...WITH CONDITIONS
DETERIORATING THEREAFTER. BY OR SHORTLY AFTER 00Z...LOW-LEVEL
(925-850 MB) FLOW WILL ASSUME MORE OF A SOUTHERLY COMPONENT. THIS IN
COMBINATION WITH OUR STALLED OUT BACKDOOR FRONT WILL RESULT IN
OVERRUNNING AND THE DEVELOPMENT OF MVFR CEILINGS AND AREAS OF LIGHT
RAIN...WITH A POTENTIAL FOR CONDITIONS TO FURTHER DETERIORATE TO IFR
AND POSSIBLY LIFR BY 12Z MON AND REMAINING THROUGH AROUND 18Z MON.
WHETHER OR NOT IFR/LIFR CONDITIONS DEVELOP PRIOR TO 12Z MON WILL
HEAVILY DEPEND ON WHETHER OR NOT MEASURABLE PRECIPITATION DEVELOPS
AND PERSISTS IN VICINITY OF THE TAF SITES. THE MOST LIKELY TIMEFRAME
FOR THE RAIN IS BETWEEN 02Z AND 09Z...BEGINNING AND ENDING FROM WEST
TO EAST.
LOOKING AHEAD:
CONDITIONS ARE EXPECTED TO FURTHER DETERIORATE TO IFR AND
POTENTIALLY LIFR OVER CENTRAL NC ON MONDAY AS PRECIPITATION FALLING
INTO THE INITIALLY COOL/DRY AIRMASS IN PLACE RESULTS IN THE
DEVELOPMENT OF A COLD AIR DAMMING WEDGE. SOME UNCERTAINTY PERSISTS
W/REGARD TO THE STRENGTH OF THE CAD WEDGE AND WHETHER OR NOT
CEILINGS WILL BECOME IFR/LIFR OR REMAIN MVFR OR BORDERLINE IFR. IF
WIDESPREAD LIGHT RAIN DEVELOPS TONIGHT AND PERSISTS INTO MONDAY...
THEN THE IFR/LIFR SCENARIO WOULD BE MORE LIKELY. CONVERSELY...IF
PRECIPITATION IS INTERMITTENT AND PATCHY...THEN MVFR OR BORDERLINE
IFR CEILINGS WOULD BE MORE LIKELY. CONDITIONS ARE EXPECTED TO
IMPROVE TO VFR EITHER LATE MONDAY NIGHT OR SHORTLY AFTER SUNRISE
TUESDAY AS DRY HIGH PRESSURE BUILDS BACK INTO THE AREA FROM THE
WEST/NW. HOWEVER...VFR CONDITIONS WILL BE SHORT-LIVED AS A POTENT
UPPER LEVEL LOW AND ASSOCIATED SFC LOW PRESSURE SYSTEM ARE PROGGED
TO TRACK OVER THE CAROLINAS/VA MID-WEEK. EXPECT CONDITIONS TO
DETERIORATE TUE NIGHT...WITH WIDESPREAD RAIN AND SUB-VFR CONDITIONS
DURING THE DAY WED...FOLLOWED BY A RETURN TO VFR CONDITIONS IN THE
WAKE OF A COLD FRONTAL PASSAGE WED EVE/NIGHT. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT/GIH
NEAR TERM...HARTFIELD/VINCENT
SHORT TERM...VINCENT
LONG TERM...BADGETT
AVIATION...KC/VINCENT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1137 AM CST SUN JAN 8 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
215 AM CST SUN JAN 8 2012
MAIN FORECAST CONCERN IS HIGH TEMPERATURES MONDAY AND TUESDAY
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED RIDGING ALONG THE WEST COAST OF THE U.S. INTO SOUTHERN
ALBERTA...AN UPPER LOW OVER ARIZONA...A SHORTWAVE TROUGH OVER
EASTERN MONTANA AND BROAD TROUGHING OVER SOUTHEAST CANADA. LACK OF
ANY SIGNIFICANT FEATURES NEAR THE FORECAST AREA RESULTING IN DRY
CONDITIONS ALONG WITH CLEAR SKIES. WITH A SURFACE HIGH PRESSURE
RIDGE IN PLACE AND A DRY ATMOSPHERE SEEN ON THE 00Z DVN AND MPX
SOUNDINGS...TEMPERATURES HAVE FALLEN INTO THE TEENS AND
20S...COLDEST IN THE TYPICAL COLD SPOTS IN WISCONSIN. UPSTREAM...
THERE IS AN AREA OF MID CLOUDS CROSSING THE DAKOTAS AHEAD OF
MONTANA SHORTWAVE TROUGH. 850MB TEMPS ACROSS THE NORTHERN
PLAINS/UPPER MIDWEST HAVE HELD FAIRLY STEADY THE PAST 12
HOURS...AROUND -4C AT BIS...ABR AND MPX FOR THEIR 12Z SOUNDINGS
YESTERDAY AND 00Z SOUNDINGS TODAY.
TODAY AND TONIGHT...SHORTWAVE TROUGH SEEN OVER EASTERN MONTANA IS
PROGGED TO DIG SOUTH INTO THE CENTRAL PLAINS...IN RESPONSE TO THE
UPPER RIDGING OVER THE WESTERN U.S. BUILDING NORTHEAST TOWARDS THE
NORTHERN PLAINS. THE AREA OF MID CLOUDS AHEAD OF THIS SHORTWAVE
THROUGH APPEAR TO SCATTER OUT/DISSIPATE AS THEY COME INTO THE
FORECAST AREA THIS AFTERNOON...LIKELY DUE TO THE SHORTWAVE DIGGING
SOUTH VERSUS EAST. THEREFORE...ANTICIPATING A MOSTLY SUNNY DAY
TODAY. WITH 925MB TEMPS EXPECTED AROUND -2C AT 18Z...HIGHS SHOULD
END UP A FEW DEGREES WARMER THAN YESTERDAY. FOR TONIGHT...MODELS
ALSO PROG A SHORTWAVE TO RIDE ON TOP OF THE BUILDING RIDGING INTO
THE NORTHERN PLAINS...FORECAST TO DROP DOWN INTO NORTHWEST WISCONSIN
AT 12Z MONDAY. THIS SHORTWAVE SHOULD HAVE A WARM FRONT ASSOCIATED
WITH IT...CROSSING THE FORECAST AREA VERY LATE TONIGHT. THIS
FRONT...IN CONJUNCTION WITH A TIGHTENING PRESSURE GRADIENT...SHOULD
HELP TO AT LEAST STABILIZE THE TEMPERATURE FALL AND POSSIBLY START
BRINGING TEMPERATURES UP AROUND 12Z. WITH CLEAR/MOSTLY CLEAR SKIES
IN THE EVENING...LOWS SHOULD FALL INTO THE 20S. NOT ANTICIPATING
MUCH MORE THAN SOME MID/HIGH CLOUD TO ACCOMPANY THE WARM FRONT...SO
NO PRECIPITATION IS FORECAST.
MONDAY THROUGH TUESDAY NIGHT...THE UPPER RIDGING THAT WAS BUILDING
TOWARDS THE NORTHERN PLAINS TONIGHT IS PROGGED TO FLATTEN OUT AND
PUSH EAST...MOVING INTO THE FORECAST AREA FOR TUESDAY. THE FEATURE
RESPONSIBLE FOR THIS IS A POTENT SHORTWAVE TROUGH...EXPECTED TO DROP
DOWN THROUGH ALBERTA ON TUESDAY...THEN DIG INTO EASTERN MONTANA AND
THE WESTERN DAKOTAS BY 12Z WEDNESDAY. FOR OUR AREA...THE MAIN
CONCERN IS TEMPERATURES...WITH THE UPPER RIDGING BRINGING WITH IT A
SURGE OF PACIFIC AIR MODIFIED BY DOWNSLOPING OFF THE ROCKIES. 925MB
TEMPS CLIMB TO 0-2C FOR 18Z MONDAY AND 2-6C FOR 18Z TUESDAY. COOLEST
READINGS ARE NORTH OF I-94. THIS CLIMB IN TEMPERATURES IS
ACCOMPANIED BY WHAT SHOULD BE BREEZY WEST TO SOUTHWEST WINDS...NOTED
BY 925MB WINDS STAYING UP BETWEEN 20-35KT FOR THE ENTIRE TIME
PERIOD. AMOUNT OF SUNSHINE WILL BE CRITICAL IN DETERMINING HOW WARM
WE GET...GIVEN THE LACK OF SNOW COVER. LOOKS TO BE SOME MID/HIGH
CLOUDS AROUND MONDAY MORNING...BUT THESE SHOULD SCATTER/CLEAR OUT IN
THE AFTERNOON AS THE UPPER RIDGE FLATTENS. ANOTHER WAVE OF MID/HIGH
CLOUDS LOOKS TO COME THROUGH MONDAY NIGHT INTO TUESDAY MORNING...BUT
AGAIN CLEARING OUT FOR THE AFTERNOON. THEREFORE...PLENTY OF
SUN IS ANTICIPATED...ESPECIALLY TUESDAY FOR WARMING. PREVIOUS
FORECAST HIGHS FOR BOTH MONDAY AND TUESDAY LOOK VERY
REASONABLE...STAYING ON THE HIGH END OF GUIDANCE WHICH HAS WORKED
FOR THE RECENT ABOVE NORMAL STRETCH. POTENTIAL DEFINITELY EXISTS
TO BREAK SOME RECORD HIGHS. LOWS MONDAY NIGHT LIKELY TO STAY WELL
ABOVE NORMAL TOO...ESPECIALLY OVER HIGHER TERRAIN AREAS. FOR
TUESDAY NIGHT...A COLD FRONT WELL AHEAD OF THE POTENT UPPER TROUGH
LOOKS TO MOVE THROUGH THE AREA BETWEEN 06-12Z. SKIES SHOULD STAY
MOSTLY CLEAR...BUT COLD ADVECTION REALLY DOESNT GET GOING UNTIL
AFTER 12Z. THEREFORE HAVE STAYED ON THE WARM SIDE OF
GUIDANCE...ESPECIALLY GIVEN THE WARM TUESDAY.
.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT
215 AM CST SUN JAN 8 2012
MAIN FORECAST CONCERN AND UNCERTAINTY FOR THE LONG TERM FORECAST
CONTINUES TO REVOLVE AROUND THAT POTENT TROUGH APPROACHING THE
NORTHERN PLAINS 12Z WEDNESDAY. 08.00Z ECMWF/GFS/CANADIAN ALL SHOW
THE TROUGH DIGGING INTO THE NORTHERN PLAINS ON WEDNESDAY THEN
PUSHING EAST...BUT THE EXTENT OF THE DIGGING AND THE TIMING OF HOW
FAST IT MOVES EAST ARE BOTH IN QUESTION. THE ECMWF AND TO SOME
DEGREE THE CANADIAN ARE BY FAR THE DEEPEST...AND BOTH PRODUCE A
TROWAL AREA OF PRECIPITATION THAT CROSSES THE FORECAST AREA MOSTLY
WEDNESDAY NIGHT. THE GFS...BEING LESS AMPLIFIED AND MORE
PROGRESSIVE...KEEPS ANY TROWAL AREA OF PRECIPITATION NORTH OF THE
AREA. ALL SOLUTIONS AGREE ON PRETTY DRAMATIC COOLING...WITH 850MB
TEMPS DROPPING FROM 4-6C AT 12Z WEDNESDAY TO -12 TO -16C BY 12Z
THURSDAY AND POTENTIALLY NEAR -20C BY 00Z FRIDAY. FOR NOW...TO
HANDLE THE UNCERTAINTIES FOR WEDNESDAY THROUGH THURSDAY...HAVE
STAYED WITH THE CONSENSUS APPROACH FOR BOTH PRECIPITATION CHANCES
AND TEMPERATURES. ONE DISTINCT CHANGE IS THAT WEDNESDAY ENDS UP
WARMER...DUE TO THE COOLING WHICH HAS TRENDED SLOWER. WOULD NOT BE
SURPRISED IF WEDNESDAY MAY HAVE TO BE WARMED EVEN MORE.
THE PERIOD FOR THURSDAY NIGHT THROUGH SATURDAY NIGHT DOES NOT GET
ANY EASIER TO FORECAST...AGAIN RELATED TO HOW FAST THE POTENT TROUGH
CAN EXIT TO THE NORTHEAST. ONE THING FOR CERTAIN IS THAT THERE IS A
STRONG CONSENSUS FOR RIDGING TO BUILD OVER THE WESTERN U.S. INTO
SOUTHWEST CANADA DURING THIS TIME. HOW MUCH OF THIS SPREADS EAST
INTO THE FORECAST AREA IS UNKNOWN. THE 08.00Z GFS TRIES TO SPREAD
SOME RIDGING INTO THE FORECAST AREA LATE SATURDAY...BUT THE ECMWF
AND GFS ENSEMBLES WOULD PREFER TROUGHING TO STAY LOCKED IN PLACE.
THINK THE LATTER SCENARIO IS MORE LIKELY. THIS MEANS ONLY A SLOW
MODERATION IN TEMPERATURES. POTENTIAL WOULD EXIST FOR SOME
PRECIPITATION CHANCES WITH SHORTWAVES RIDING THROUGH THE NORTHWEST
FLOW ALOFT...AS INDICATED BY THE NEW 08.00Z ECMWF FOR SATURDAY.
HOWEVER...TIMING SOMETHING THAT FAR OUT IN THE FORECAST AND GIVEN
THE UNCERTAINTIES IN THE UPPER PATTERN...HAVE LEFT THE THURSDAY
NIGHT THROUGH SATURDAY NIGHT TIME PERIOD DRY.
&&
.AVIATION...THROUGH 18Z MONDAY
1136 AM CST SUN JAN 8 2012
A TROUGH WILL MOVE THROUGH THE REGION LATE TONIGHT AND EARLY
MONDAY MORNING. A BROKEN DECK OF HIGH CLOUDS WILL MOVE INTO THE
REGION AFTER 09.02Z. THIS CLOUD DECK WILL THEN GRADUALLY LOWER TO
AROUND 5K FEET TOWARD SUNRISE. BETWEEN 09.13Z AND 09.16Z...THESE
CLOUDS WILL MOVE QUICKLY OUT OF THE AREA. IN THE WAKE OF THIS
TROUGH THE WINDS WILL QUICKLY SHIFT FROM SOUTH TO WEST AND
INCREASE INTO THE 15 TO 25 KNOT RANGE. IN ADDITION...THE WINDS
WILL START TO GUST TO AROUND 30 KNOTS IN NORTHEAST IOWA AND
SOUTHEAST MINNESOTA AROUND 09.17Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
215 AM CST SUN JAN 8 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION...BOYNE