Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/24/13
AREA FORECAST DISCUSSION...CORRECTED
NWS GRAND JUNCTION CO
420 PM MST SAT NOV 23 2013
MADE SOME MINOR CORRECTIONS TO TYPOGRAPHICAL ERRORS
.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 311 PM MST SAT NOV 23 2013
COMPLEX PATTERN TODAY AS COLDER AIR MOVED INTO SOUTHEAST UTAH...
LOWERING THE SNOW LEVELS TO THE VALLEY FLOORS. BUT SOUTHWEST
COLORADO HAS STAYED IN THE WARM SECTOR WITH THE SNOW LEVEL AROUND
8000 FEET. TELLURIDE AWOS OBSERVED LIGHT RAIN EARLIER TODAY.
SOUTHWEST COLORADO HAS BEEN A CHALLENGE WITH RESPECT TO
PRECIPITATION TYPE DURING THE PAST DAY OR TWO. CONFIDENCE IS
INCREASING THAT SNOW LEVELS WILL LOWER TO THE VALLEY FLOORS
(EXCEPT SOUTH OF CORTEZ) AS THE MOIST CONVEYOR BELT OVER ERN
ARIZONA SHIFTS INTO NWRN NEW MEXICO AND EXTREME SWRN COLORADO.
MID LEVEL TEMPS IN THE CONVEYOR BELT ARE COLDER AND DIABATIC
COOLING PROCESSES WILL RESULT IN RAIN CHANGING OVER TO SNOW. WITH
SOUTHEAST LOW LEVEL FLOW...THE RAP AND DOWNSCALED 5KM NAM SHOW THE
QPF BULLSEYE ALONG THE MONTEZUMA/LA PLATA COUNTY LINE AND
MONTICELLO UTAH WITH AREAS EXCEEDING 1 INCH OF PCPN DURING THE
NEXT 12 HOURS. THIS EQUATES TO A SNOW ACCUMULATION OF 6-12 INCHES
OF "SIERRA CEMENT" (HEAVY WET SNOW) FOR THE THIS AREA OVERNIGHT.
FOR EAST CENTRAL UTAH AND THE UNCOMPAHGRE/GRAND VALLEY...SOUTHEAST
FLOW WILL A WARMING EFFECT THAT ERODES THE COLDER SURFACE AIR.
THIS ELIMINATES THE CHANCE OF A REPEAT PERFORMANCE OF HEAVY SNOW
FROM CANYONLANDS NATIONAL PARK TO DEBEQUE CANYON. THE OVERRUNNING
PATTERN WILL NO LONGER EXIST AND THE AREAL EXTENT OF PRECIPITATION
WILL HAVE LESSENED. FARTHER NORTH...MOSTLY DRY ALTHOUGH SOME
DISSIPATING BANDS OF LIGHT SNOW MAY GENERATE FLURRIES OVER NE
UTAH/NW COLORADO.
SUNDAY AND SUNDAY NIGHT...THE CLOSED UPPER LOW WILL BE WEAKENING
AS IT MOVES INTO NWRN NEW MEXICO. ACTIVE WEATHER WILL STILL EXIST
BENEATH THE UPPER LOW SO ACCUMULATING SNOW CONTINUES ACROSS SW
COLORADO. THE MOISTURE FIELD OVER ERN UTAH AND NORTHWEST COLORADO
WILL BE ERODING. AS THE LOW CONTINUES TO TRACK ACROSS NEW
MEXICO...LOW LEVEL FLOW BECOMES NORTHWEST WHICH FAVORS THE NWRN SAN
JUANS AND THE SRN UNCOMPAHGRE PLATEAU (DALLAS DIVIDE/RIDGWAY AND
OURAY). HOWEVER...SNOW RATES WILL BE DIMINISHING AS THE UPPER LOW
WILL BE MOVING DOWNSTREAM. BY THE TIME THE UPPER LOW DOES DEPART
THE REGION LATE SUNDAY NIGHT...STORM TOTAL QPF AND SNOWFALL WILL
BE QUITE IMPRESSIVE FOR THE SRN PORTION OF THE FORECAST AREA.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 311 PM MST SAT NOV 23 2013
THE UPPER LOW WILL HAVE TRANSLATED EAST OF THE ROCKIES TO NEAR THE
TEXAS PANHANDLE BY SUNRISE ON MONDAY...THEN BE FORCED SOUTHWARD BY
A STRONG DIP IN THE NORTHERN STREAM ACROSS THE UPPER MISSISSIPPI
VALLEY. LINGERING WRAP AROUND MOISTURE WILL BE EXITING THE FAR
SOUTHERN CWA BY LATE MORNING AS THE UPPER LOW BEGINS TO BE FORCED
SOUTHWARD. THE RETREATING MOISTURE WILL BE REPLACED BY ANOTHER
BATCH OF HIGH LEVEL MOISTURE BEING TRANSPORTED IN ON THE NORTHERLY
STREAM. NAM/GFS DIFFERING A BIT WITH THE GFS SATURATING THE UPPER
END OF THE DENDRITIC LAYER NEAR 500MB. THE NAM A BIT MORE
AGGRESSIVE WITH SATURATION DOWN TO THE TOP OF THE NORTHERN DIVIDE
MOUNTAINS THROUGH A LARGER PORTION OF THE DENDRITIC LAYER. ASCENT
IS WEAK WITH OROGRAPHICS THE MAIN DRIVER IN THE NORTH FLOW SO
WOULD EXPECT ANY ACCUMULATIONS TO BE ON THE LIGHT SIDE. FOR NOW
WILL KEEP JUST SOME SMALL POPS IN PLACE THROUGH THE AFTERNOON
UNTIL MODEL AGREEMENT ALIGNS BETTER. TEMPERATURES ARE SURE TO BE
AFFECTED BY THE SNOW COVER ESPECIALLY OVER SOUTHEAST UTAH INTO
SOUTHWEST COLORADO SO UNDERCUT GUIDANCE NUMBERS IN MANY AREAS.
THERE SHOULD BE SLOW WARM-UP GOING INTO THE MID TO LATE WEEK PERIOD
THOUGH THE STRONG NORTHERN STREAM FLOW JUST OFF TO OUR NORTHEAST
WILL CONTINUE TO REINFORCE THE COLD AIR ALOFT. VALLEY INVERSIONS
STRENGTHENED BY SNOW PACK WILL CONTINUE TO PUT A DAMPER ON WARMING
SO AGAIN TEMPERATURES FROM BLENDED MODELS WERE LOWERED. A WEAK
WAVE PASSAGE ON THURSDAY MAY BRING A BIT OF PASSING HIGH CLOUDINESS
BUT IS NOT LIKELY TO ADD MUCH TO MIXING. OUT WEST...THE EASTERN
PACIFIC TROF WILL BE SPLITTING WITH ONE BATCH CATCHING THE
WESTERLIES ACROSS THE NORTHERN CONUS BORDER. THE OTHER MAIN BATCH
WILL CLOSE OFF ANOTHER LOW ALONG THE CALIFORNIA COASTLINE. SOME OF
THIS SOUTHERN ENERGY SHEARS OUT OF THE LOW AND PROGRESSES ACROSS
THE CENTRAL ROCKIES PULLING MOISTURE WITH IT. FOR NOW IT SEEMS
THIS WILL BE MAINLY IN THE FORM OF HIGH CLOUDINESS THROUGH THE
LATE WEEK PERIOD. SO FOR NOW A MAINLY DRY FORECAST LOOKS ON TRACK
FOR HOLIDAY TRAVEL WITH TEMPERATURES GRADUALLY WARMING.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 311 PM MST SAT NOV 23 2013
ANOTHER BATCH OF ENERGY AND MOISTURE IS LIFTING ACROSS SOUTHWEST
COLORADO AND FAR EASTERN UTAH THIS AFTERNOON...BUT IS MIXING IN
WITH A BIT OF DRIER AIR ALOFT. THIS IS LEAVING A MORE SHOWERY FEEL
TO PRECIPITATION WITH VFR CONDITIONS OVER MANY OF THE FORECAST
TERMINALS LATE THIS AFTERNOON. THE STRONGER MOISTURE IS JUST TO
THE WEST OF THE 4 CORNERS AND IS AIDING IN SNOW AND LOW CLOUDINESS
OVER THE KCNY TERMINAL. MOIST UPSLOPE FLOW IS ALSO KEEPING MVFR
CIGS PUSHED UP AGAINST THE SOUTHERN SAN JUANS AND THE KDRO
TERMINAL. THE WESTERN MOISTURE PLUME WILL BE SPREADING EASTWARD
OVERNIGHT AND EXPECT DETERIORATING FLIGHT CONDITIONS OVER MANY OF
THE TAF SITES OVERNIGHT WITH THE BIGGEST IMPACTS OVER KDRO...KTEX
CLOSER TO THE CORE OF THE PASSING STORM SYSTEM TO THE SOUTH.
MOUNTAIN OBSCURATION WILL BE PROMINENT OVER MANY AREAS THROUGH
SUNDAY NIGHT BEFORE SOME DRYING BEGINS TO PUSH IN FROM THE NORTH.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WARNING UNTIL 3 AM MST MONDAY FOR COZ018-019.
WINTER WEATHER ADVISORY UNTIL NOON MST SUNDAY FOR COZ021.
WINTER STORM WARNING UNTIL NOON MST SUNDAY FOR COZ022-023.
UT...WINTER STORM WARNING UNTIL 3 AM MST MONDAY FOR UTZ028.
WINTER WEATHER ADVISORY UNTIL NOON MST SUNDAY FOR UTZ029.
&&
$$
SHORT TERM...PF
LONG TERM...15
AVIATION...15
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
936 AM MST FRI NOV 22 2013
.UPDATE...
ISSUED AT 935 AM MST FRI NOV 22 2013
RAIN BUT LITTLE IF ANY SNOW HAS BEEN OBSERVED IN THE DURANGO AREA
(CO ZONE 22) THIS MORNING. A COUPLE CALLS TO SPOTTERS AROUND 7000 FT
ELEV THERE THIS MORNING INDICATED RAIN...OR RAIN/SNOW MIX BUT NO
ACCUMULATIONS. NAM AND RUC MODELS BUFKIT FORECAST SOUNDINGS TELLING
DIFFERENT PRECIP STORIES FOR TODAY...WITH THE NAM FAVORING SNOW AND
THE RUC FAVORING RAIN. CURRENT TEMPS FROM MESONET SHOWED TEMPS
MOSTLY ABOVE FREEZING...AND WITH TEMPS AND DEWPOINTS EXPECTED TO
STAY ABOVE FREEZING THERE TODAY...I WILL LEAN TOWARD RAIN OR
RAIN/SNOW MIX BUT WITH LITTLE ACCUMULATION. THUS...PLAN TO CANCEL
THE WINTER STORM WARNING FOR THE DURANGO AREA (CO ZONE 22) AND
REPLACE WITH A WINTER WEATHER ADVISORY FOR TONIGHT. NEW HIGHLIGHT
STATEMENT AND UPDATED GRIDDED/WORDED FORECAST OUT SHORTLY.
UPDATE ISSUED AT 750 AM MST FRI NOV 22 2013
CANCELLED THE WINTER WEATHER ADVISORY FOR THE I-70 CORRIDOR FROM
GRAND JCT TO RIFLE. LITTLE IF ANY SNOW OCCURRED OVERNIGHT. RADAR
INDICATES SOME SNOW WAS POSSIBLE FROM ABOUT WHITEWATER TO THE MESA-
DELTA COUNTY LINE. SNOW CONTINUED TO BE REPORTED AT THE DELTA AND
MONTROSE AIRPORTS SO WILL KEEP THE ADVISORY FOR CO ZONE 11 INTACT.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 356 AM MST FRI NOV 22 2013
HEALTHY AREA OF PRECIPITATION HAS MOVED INTO SW CO OVERNIGHT PRODUCING
LIGHT TO MODERATE RAIN AND SNOW FROM ABOUT OLATHE TO GATEWAY AND
SOUTH. SNOWFALL RATES VIA SNOTELS IN THE SAN JUANS LOOK TO BE
ABOUT ONE INCH PER HOUR FOR THE LAST FEW HOURS...AND MUCH SLOWER
AS YOU GO NORTH. KEPT THE ADVISORIES GOING FOR ZONES 6 AND
7...BUT A LITTLE BIT CONCERNED ABOUT MOISTURE BEING SHADOWED OVER
THE UNCOMPAHGRE AND REACHING AS FAR NORTH AS RIFLE TO MAKE MUCH IN
THE WAY OF SNOW ACCUMULATION. RADAR RETURNS ARE CREEPING TOWARD
THE VALLEY SO A TRACE OF SNOW IS EXPECTED BY THE BEGINNING OF THE
WORKDAY AND POTENTIALLY MORE BY MID-MORNING. EXPECTING TEMPS TO
WARM UP ENOUGH FOR VALLEYS TO CHANGE BACK OVER TO RAIN DURING THE
DAY AND POTENTIALLY BACK TO SNOW AGAIN TONIGHT FOR A FUN WINTRY
MIX.
THE HEAVIEST SNOW DURING THE FIRST HALF OF TODAY WILL OCCUR ALONG
SOUTHWEST FACING SLOPES FROM AN AREA STRETCHING WEST TO EAST
ENCOMPASSING ELEVATIONS ABOVE 7000 FT IN LA PLATA...SAN
JUAN...HINSDALE...AND ARCHULETA COUNTIES. STILL STRUGGLING WITH
SNOW LEVELS AS THE FORECAST MODELS STILL SHOW A SHALLOW COLD FRONT
GETTING ALL THE WAY DOWN TO THE 4 CORNERS AROUND NOON FRI. THIS
COULD BRING TEMPS DOWN A FEW DEGREES IN THE VALLEYS...AND COMBINED
WITH MOIST SOUTHWEST FLOW ALOFT...PRODUCE SNOW IN THE VALLEYS AS WELL.
MOISTURE TRANSPORT VECTORS SHOW MOISTURE CURRENTLY WRAPPING INTO
THE FOUR CORNERS AREA AHEAD OF THE UPPER LEVEL LOW CURRENTLY
SPINNING OVER SOUTHERN CALIFORNIA. THOUGH IR SATELLITE OVERNIGHT
SHOWS THIS SYSTEM BECOMING A LITTLE LESS ORGANIZED...IT IS STILL
PACKING A BIG PUNCH OF MOISTURE WHICH WILL COME IN A FEW DIFFERENT
WAVES THROUGH SATURDAY NIGHT. THE UPPER LEVEL LOW CAUSING THIS
PROLONGED PERIOD OF CLOUDS AND PRECIPITATION IS EXPECTED TO SHIFT
SOUTHEAST SLIGHTLY BEFORE MAKING AN EAST NORTHEAST TURN INTO THE 4
CORNERS REGION SUNDAY...ALLOWING A COUPLE OF PUSHES OF ENERGY
THROUGH BETWEEN NOW AND THEN.
MOISTURE IS EXPECTED TO REMAIN MAINLY IN THE SAN JUANS REGION
EARLY THIS MORNING...AND GRADUALLY MOVE NORTH INTO THE CENTRAL
MTNS INCLUDING ASPEN AND VAIL AROUND NOON OR EARLY THIS AFTERNOON.
MODELS INDICATE SHOWERS TAPERING OFF TONIGHT EXCEPT IN THE LA SALS
AND ABAJOS WHERE IT WILL CONTINUE THROUGH THE NIGHT. AS THE LOW
PUSHES EAST SATURDAY...ANOTHER SWATH OF MOISTURE AND VORT MAX WILL
PUSH BACK INTO THE AREA ACCOMPANIED BY A 85 KT JET...ONCE AGAIN
DUMPING THE HEAVIEST PRECIPITATION OVER SW CO.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 356 AM MST FRI NOV 22 2013
STILL EXPECTING SHOWERS TO CONTINUE THROUGH SATURDAY NIGHT...BUT
WILL BEGIN TO TAPER OFF WITH THE LOW PRESSURE CENTER FINALLY
MAKING A PUSH TOWARD THE AREA.
SUNDAY THROUGH THURSDAY...THE MID-RANGE MODELS REMAIN IN GOOD
AGREEMENT WITH THE CLOSED LOW OVER THE SWRN U.S. BEGINNING TO LIFT
ENE OVER CENTRAL AZ SUNDAY. THE NAM12...GFS AND ECMWF SHOW A
LARGE BAND OF CLOUDS AND PCPN WRAPPING AROUND THE N AND NW
QUADRANTS OF THE 500 MB LOW WITH MOISTURE CONTINUING TO FEED INTO
THE SYSTEM FROM THE SOUTH. AS THE UPPER LOW SLIDES OVER THE TX/OK
PANHANDLE EARLY MONDAY MORNING...THIS BAND REMAINS SOMEWHAT
STATIONARY OVER CENTRAL AND SW CO...AND SE UT. THE MODELS SHOW THE
PCPN AREA GLIDING SE AND EXITING THE FORECAST AREA BY MONDAY
EVENING. THE BEST FOCUSES FOR SIGNIFICANT PCPN WILL REMAIN BENEATH
THIS BAND...AND OVER THE SAN JAN MOUNTAINS DUE TO THE ADDED
INGREDIENT OF SOUTHERLY WINDS AT MID LEVELS ENHANCING THE
OROGRAPHIC COMPONENT OF THE PCPN. ONE MITIGATING FACTOR WILL BE
THE INDICATION OF A DRIER SLOT MOVING OVER THE AREA SUNDAY BEHIND
THE SURFACE COLD FRONT WHICH WILL HAVE MOVED OVER ERN NM AND WRN
TX SUNDAY.
DRY RIDGING WILL BRING A WARMING TREND TO THE AREA TUESDAY THROUGH
WEDNESDAY...THEN THE NEXT STORM WILL APPROACH FROM THE PACNW WED
NIGHT AND THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 356 AM MST FRI NOV 22 2013
WIDESPREAD RAIN AND SNOW WILL CONTINUE THROUGH SAT MORNING. MVFR
CIGS AND VSBYS WILL BE COMMON AT ALL TAF SITES AND AIRPORTS ACROSS
THE AREA...WITH MOUNTAINS AND HIGH PASSES OBSCURED. EXPECT PERIODS
OF IFR CONDITIONS AT KASE...KEGE...KMTJ...KTEX...KDRO AND KCEZ...
AS WILL AS ALL AIRPORTS FROM KMTJ SOUTH. BRIEF LIFR IS POSSIBLE AT
KTEX...KDRO...KCEZ AND KPSO.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MST TONIGHT FOR COZ014.
WINTER STORM WARNING UNTIL 6 PM MST SATURDAY FOR COZ018-019.
WINTER WEATHER ADVISORY UNTIL 11 AM MST THIS MORNING FOR COZ011.
WINTER STORM WARNING UNTIL MIDNIGHT MST TONIGHT FOR COZ009-010-
012-017.
WINTER STORM WARNING UNTIL 6 AM MST SATURDAY FOR COZ023.
WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 6 AM MST
SATURDAY FOR COZ022.
UT...WINTER STORM WARNING UNTIL 6 PM MST SATURDAY FOR UTZ028.
&&
$$
UPDATE...JAD
SHORT TERM...JAM
LONG TERM...JAM/CC
AVIATION...CC
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1040 PM MST THU NOV 21 2013
.UPDATE...
ISSUED AT 947 PM MST THU NOV 21 2013
LATEST 00Z RUNS HAVE GENERALLY SHIFTED THE HEAVIER ACCUMS FARTHER
TO THE SOUTH AND WEST. AREA OF ISENTROPIC UPGLIDE/FRONTOGENESIS
WILL SHIFT NORTHWARD ACROSS THE AREA TONIGHT...THOUGH UPGLIDE
WEAKENS AS IT SHIFTS INTO NORTHERN PORTIONS OF THE FORECAST AREA
ON FRIDAY. THEREFORE...HEAVIEST HIT AREAS STILL APPEAR TO BE
ACROSS THE SOUTHERN MOUNTAINS WITH THE EASTERN SAN JUANS BEING THE
BIG WINNERS WITH OVER A FOOT TO 16 INCHES POSSIBLE BY FRIDAY
EVENING. H7 WINDS SHIFT AROUND FROM THE EAST TOMORROW...SO THINK
THAT THE EASTERN SLOPES OF THE WETS AND SANGRES COULD PICK UP
AROUND A FOOT IN SOME PLACES MEETING THE 24 HOUR WARNING CRITERIA
AMOUNTS WITH THE AIDE OF SOME UPSLOPE FLOW. BOTH GFS AND NAM12
SUGGEST A GOOD 6 INCHES ACROSS MOST OF THE SAN LUIS
VALLEY...THOUGH WESTERN VALLEY EDGES COULD PICK UP SUBSTANTIALLY
MORE...SO WINTER STORM WARNING THERE STILL LOOKS GOOD. WARNING
CRITERIA AMOUNTS MAY HIT ON THE LOW SIDE ACROSS THE RATON MESA
REGION...BUT NAM12 IS STILL HITTING THIS AREA WITH AROUND 8
INCHES...AS OPPOSED TO GFS`S MORE CONSERVATIVE 3 TO 5. HUNG ON TO
THE LOWER SIDE OF THESE AMOUNTS FOR NOW AS ISENTROPIC UPGLIDE
LOOKS STRONGEST FARTHER SOUTH ACROSS NM AND TEXAS. REMAINDER OF
HEADLINES STILL LOOK GOOD. WE MAY COME UP ON THE SHORT SIDE OF
ADVISORY NUMBERS FOR CROWLEY COUNTY...BUT THEN AGAIN...GFS IS MORE
GUNG HO UP THAT WAY SATURDAY AFTERNOON AS THE BAND LIFTS
NORTHWARD...SO WILL HOLD THE COURSE.
FRIDAY EVENING...MODELS SPREAD A DRY SLOT NORTHWARD ACROSS THE
AREA WHICH CUTS BACK ON THE HEAVIER PRECIPITATION FAIRLY QUICKLY.
NAM12 STILL KEEPS SOME MODERATE 2-4 INCH ACCUMULATIONS ACROSS
NORTHWEST PORTIONS OF THE ADVISORY/WARNING AREAS...BUT GFS IS MUCH
LIGHTER. WILL LEAVE THE END TIME OF THE HIGHLIGHTS AT 6 PM FRI FOR
NOW AND LET SOME OF THE HIGHER RES MODELS RESOLVE THIS TIMING A
LITTLE BETTER. -KT
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 248 PM MST THU NOV 21 2013
...SNOW BAND TO BRING LOCALLY HEAVY SNOW AMOUNTS TO PART OF SOUTHERN
COLORADO...
CURRENTLY...
ARCTIC AIRMASS HAS MOVED ACROSS THE PLAINS...WITH TEMPS IN THE 20S
PLAINS AND OVC SKIES. COLD AIR HAS NOT MADE IT OVER THE MTNS YET AND
THE SLV STILL HAD TEMPS AOA 50F.
A WELL DEFINED JET STREAK WAS NOTED RAGING ACROSS S CALIF INTO THE 4
CORNERS.
REST OF TODAY THROUGH TOMORROW...
SIMULATIONS CONTINUE TO INDICATE A SNOW BAND CAPABLE OF LOCALLY
HEAVY SNOW WILL SET UP OVER SOUTHERN COLORADO LATER THIS EVENING
INTO TOMORROW. THE GUIDANCE HAS BEEN VERY CONSISTENT WITH THIS BAND
OVER THE LAST SEVERAL DAYS. LATEST 18Z NAM CONTINUES TO SHOW THIS
PATTERN AND THE HRRR SUPPORTS THE DEVELOPMENT OF THIS BAND. THIS
BAND IS ASSOCIATED WITH A BAROCLINIC ZONE IN THE 600-7000MB LAYER
THAT IS PROGGED NOT TOO MOVE TOO MUCH. IT APPEARS AT THIS TIME THE
BEST CHANCE OF HEAVIER SNOW WILL FALL GENERALLY ALONG AND SOUTH OF
US HIGHWAY 50.
SNOWFALL AMOUNTS WITH THIS BAND FOR TONIGHT THROUGH TOMORROW
ACCORDING TO GUIDANCE ARE RATHER IMPRESSIVE..AND HAVE CUT BACK FROM
GUIDANCE...STILL 4-7" AMOUNTS WILL BE POSSIBLE OVER NEARLY ALL OF
THE SAN LUIS VALLEY AND MOST OF THE PLAINS GENERALLY SOUTH OF
HIGHWAY 50 AND WEST OF SPRINGFIELD.
THE SANGRES...WETS AND SAN JUANS SHOULD DO VERY WELL WITH THIS
EVENT...WITH 12-18" OVER THE SAN JUANS AND NEAR A FOOT OVER THE
SANGRES AND WETS.
FARTHER NORTH LESS SNOW IS LIKELY AND HAVE CUT BACK ON AMOUNTS IN
THE CENTRAL MOUNTAINS. HAVE ALSO DOWNGRADED WARNINGS TO ADVISORIES
FOR PARTS OF THE CENTRAL MOUNTAIN REGION.
THE PIKES PEAK REGION WILL SEE ON AND OF SNOW SHOWERS WITH 1-3"
POSSIBLE THROUGH THE PERIOD. THE BEST CHANCE OF SNOW MAY OCCUR LATER
TOMORROW AS THE BAND LIFTS A BIT TO THE NORTH. HOWEVER THE SNOW IS
EXPECTED TO BE DECREASING AS THE FRONTOGENETICAL FORCING LESSENS
WITH TIME.
TOMORROW WILL BE ANOTHER COLD DAY WITH HIGHS ON THE 20S ALL AREAS.
WE MAY SEE SOME BREAKS IN THE CLOUDS LATE IN THE DAY OVER THE
NORTHERN PARTS OF THE CWA. /HODANISH
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 248 PM MST THU NOV 21 2013
...SNOW AND COLD CONTINUES...
FRIDAY NIGHT-SATURDAY...SNOW ACROSS THE EASTERN PLAINS WILL SLOWLY
WIND DOWN BETWEEN 06Z-09Z EARLY SATURDAY MORNING ACROSS THE EASTERN
PLAINS AS THE BEST LIFT MOVES AWAY FROM THE AREA.
ATTENTION THEN TURNS TO THE CUT OFF LOW SPINNING OVER SOUTHERN
CALIFORNIA. THE GFS AND THE NAM ARE IN SOMEWHAT BETTER AGREEMENT
WITH THE EC MODELS HANDLING OF THE LOW AND AM NOW MORE CONFIDENT THE
LOW WILL TAKE A MORE NORTHERLY TRACK THEN PREVIOUS GFS FORECASTS
HAVE SHOWN. IN COORDINATION WITH DDC/GLD/GJT I HAVE INCREASED POPS
ACROSS ALL OF THE MOUNTAIN AREAS SATURDAY AND SUNDAY...AND ACROSS
THE PLAINS ON SUNDAY. IF CURRENT MODEL TRENDS CONTINUE...I AM FAIRLY
CERTAIN THE WINTER STORM WARNING FOR THE SAN JUANS WILL NEED TO BE
EXTENDED THROUGH AT LEAST SATURDAY EVENING. THE 18Z NAM12 SHOWS 30
INCHES OF SNOWFALL BETWEEN 00Z SATURDAY AND 12Z SUNDAY ACROSS THE
SAN JUANS. THE 12Z GFS PAINTS 20 INCHES DURING THE SAME TIME FRAME.
TOO EARLY TO EXTEND THE WARNING AT THIS TIME.
SUNDAY...AS SNOW CHANCES REMAIN HIGH ALONG THE CONTINENTAL
DIVIDE...MODELS DIFFER ON HOW MUCH SNOW WILL FALL ACROSS THE EASTERN
MOUNTAINS AND THE PLAINS ON SUNDAY. THE GFS/NAM12 SHOW A
VORT MAX ROTATING AROUND THE CUTOFF LOW BETWEEN 09Z-12Z SUNDAY
MORNING...AND PUSHING IT THROUGH THE EASTERN PLAINS. THE GFS IS MUCH
WEAKER WITH THIS FEATURE AND SHOWS NO MORE THEN A DUSTING OF SNOW
ACROSS THE PLAINS...3 TO 6 INCHES IN THE WET MOUNTAINS AND THE
SANGRES THROUGH 00Z MONDAY. THE NAM SHOWS ALMOST A FOOT OF SNOW
ACROSS THE SAME MOUNTAIN ZONES AND UP TO 3 INCHES ALONG THE HIGHWAY
50 CORRIDOR EAST OF PUB (LAA/LHX). I HAVE TAKEN THE MORE
CONSERVATIVE GFS ROUTE AT THIS TIME...INCREASING POPS AND SNOW
AMOUNTS SLIGHTLY. HIGHLIGHT CRITERIA MAY BE REACHED IN THE
SANGRES/WETS IF THE NAM SOLUTION VERIFIES.
MONDAY-THURSDAY...MODELS DRY OUT THE FORECAST AREA RATHER QUICKLY
MONDAY...WITH ONLY A FEW REMAINING SNOW SHOWERS MONDAY MORNING. WEST
AND NORTHWEST FLOW WILL KEEP THE AREA DRY THROUGHOUT THE PERIOD.
500MB AND 700MB WINDS TURN MORE WEST AND SOUTHWEST LATE WEDNESDAY
THROUGH THURSDAY AHEAD OF ANOTHER PACIFIC STORM SYSTEM. TEMPERATURES
WILL REBOUND BACK TO AVERAGE LEVELS AS WELL. -PJC
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1031 PM MST THU NOV 21 2013
VFR CIGS/VIS WILL DROP INTO THE IFR CATEGORY OVERNIGHT AS UPPER
LIFT FROM AN APPROACHING SYSTEM SPREADS SNOW INTO THE REGION. A
ROUND OF SCATTERED SHOWERS HAS BEEN SPREADING EASTWARD ACROSS THE
AREA LATE THIS EVENING AN ALL TERMINALS SHOULD START TO SEE SOME
-SHSN BY 08Z. SNOW WILL BECOME HEAVY AT TIMES AFTER 10Z FOR KALS
WITH LIFR CONDITIONS. IFR CONDITIONS WILL SPREAD INTO THE KPUB
THEN KCOS TAF SITES BY 12Z AS A BAND OF SNOW DEVELOPS ACROSS
SOUTHERN CO. THIS BAND WILL SHIFT NORTHWARD THROUGH THE MORNING ON
FRIDAY WITH IMPROVING CONDITIONS EXPECTED FROM SOUTH TO NORTH
FRIDAY AFTERNOON. ACCUMULATIONS AT THE TERMINALS WILL RANGE FROM
AROUND 6 INCHES FOR KALS...TO AROUND 2 TO 3 FOR KCOS AND KPUB BY
EARLY FRIDAY EVENING. HEAVIER SNOWFALL AMOUNTS OF A FOOT OR MORE
WILL BE POSSIBLE ACROSS THE SOUTHERN MOUNTAINS...WITH AROUND 3 TO
6 INCHES POSSIBLE MAINLY TO THE SOUTH OF HIGHWAY 50 ACROSS THE
PLAINS. WIDESPREAD MTN OBSCURATIONS WILL CONTINUE THROUGH FRIDAY
WITH LIFR CONDITIONS DUE TO PERIODS OF SNOW. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 PM MST FRIDAY FOR COZ062-063-
076>078-083-086-089-093-097>099.
WINTER WEATHER ADVISORY UNTIL 6 PM MST FRIDAY FOR COZ058-059-061-
064.
WINTER STORM WARNING UNTIL 6 PM MST FRIDAY FOR COZ069>075-079-
080-087-088-094.
WINTER STORM WARNING UNTIL 6 PM MST FRIDAY FOR COZ060-065>068.
&&
$$
UPDATE...KT
SHORT TERM...HODANISH
LONG TERM...PJC
AVIATION...KT
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1006 PM MST THU NOV 21 2013
.UPDATE...
ISSUED AT 947 PM MST THU NOV 21 2013
LATEST 00Z RUNS HAVE GENERALLY SHIFTED THE HEAVIER ACCUMS FARTHER
TO THE SOUTH AND WEST. AREA OF ISENTROPIC UPGLIDE/FRONTOGENESIS
WILL SHIFT NORTHWARD ACROSS THE AREA TONIGHT...THOUGH UPGLIDE
WEAKENS AS IT SHIFTS INTO NORTHERN PORTIONS OF THE FORECAST AREA
ON FRIDAY. THEREFORE...HEAVIEST HIT AREAS STILL APPEAR TO BE
ACROSS THE SOUTHERN MOUNTAINS WITH THE EASTERN SAN JUANS BEING THE
BIG WINNERS WITH OVER A FOOT TO 16 INCHES POSSIBLE BY FRIDAY
EVENING. H7 WINDS SHIFT AROUND FROM THE EAST TOMORROW...SO THINK
THAT THE EASTERN SLOPES OF THE WETS AND SANGRES COULD PICK UP
AROUND A FOOT IN SOME PLACES MEETING THE 24 HOUR WARNING CRITERIA
AMOUNTS WITH THE AIDE OF SOME UPSLOPE FLOW. BOTH GFS AND NAM12
SUGGEST A GOOD 6 INCHES ACROSS MOST OF THE SAN LUIS
VALLEY...THOUGH WESTERN VALLEY EDGES COULD PICK UP SUBSTANTIALLY
MORE...SO WINTER STORM WARNING THERE STILL LOOKS GOOD. WARNING
CRITERIA AMOUNTS MAY HIT ON THE LOW SIDE ACROSS THE RATON MESA
REGION...BUT NAM12 IS STILL HITTING THIS AREA WITH AROUND 8
INCHES...AS OPPOSED TO GFS`S MORE CONSERVATIVE 3 TO 5. HUNG ON TO
THE LOWER SIDE OF THESE AMOUNTS FOR NOW AS ISENTROPIC UPGLIDE
LOOKS STRONGEST FARTHER SOUTH ACROSS NM AND TEXAS. REMAINDER OF
HEADLINES STILL LOOK GOOD. WE MAY COME UP ON THE SHORT SIDE OF
ADVISORY NUMBERS FOR CROWLEY COUNTY...BUT THEN AGAIN...GFS IS MORE
GUNG HO UP THAT WAY SATURDAY AFTERNOON AS THE BAND LIFTS
NORTHWARD...SO WILL HOLD THE COURSE.
FRIDAY EVENING...MODELS SPREAD A DRY SLOT NORTHWARD ACROSS THE
AREA WHICH CUTS BACK ON THE HEAVIER PRECIPITATION FAIRLY QUICKLY.
NAM12 STILL KEEPS SOME MODERATE 2-4 INCH ACCUMULATIONS ACROSS
NORTHWEST PORTIONS OF THE ADVISORY/WARNING AREAS...BUT GFS IS MUCH
LIGHTER. WILL LEAVE THE END TIME OF THE HIGHLIGHTS AT 6 PM FRI FOR
NOW AND LET SOME OF THE HIGHER RES MODELS RESOLVE THIS TIMING A
LITTLE BETTER. -KT
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 248 PM MST THU NOV 21 2013
...SNOW BAND TO BRING LOCALLY HEAVY SNOW AMOUNTS TO PART OF SOUTHERN
COLORADO...
CURRENTLY...
ARCTIC AIRMASS HAS MOVED ACROSS THE PLAINS...WITH TEMPS IN THE 20S
PLAINS AND OVC SKIES. COLD AIR HAS NOT MADE IT OVER THE MTNS YET AND
THE SLV STILL HAD TEMPS AOA 50F.
A WELL DEFINED JET STREAK WAS NOTED RAGING ACROSS S CALIF INTO THE 4
CORNERS.
REST OF TODAY THROUGH TOMORROW...
SIMULATIONS CONTINUE TO INDICATE A SNOW BAND CAPABLE OF LOCALLY
HEAVY SNOW WILL SET UP OVER SOUTHERN COLORADO LATER THIS EVENING
INTO TOMORROW. THE GUIDANCE HAS BEEN VERY CONSISTENT WITH THIS BAND
OVER THE LAST SEVERAL DAYS. LATEST 18Z NAM CONTINUES TO SHOW THIS
PATTERN AND THE HRRR SUPPORTS THE DEVELOPMENT OF THIS BAND. THIS
BAND IS ASSOCIATED WITH A BAROCLINIC ZONE IN THE 600-7000MB LAYER
THAT IS PROGGED NOT TOO MOVE TOO MUCH. IT APPEARS AT THIS TIME THE
BEST CHANCE OF HEAVIER SNOW WILL FALL GENERALLY ALONG AND SOUTH OF
US HIGHWAY 50.
SNOWFALL AMOUNTS WITH THIS BAND FOR TONIGHT THROUGH TOMORROW
ACCORDING TO GUIDANCE ARE RATHER IMPRESSIVE..AND HAVE CUT BACK FROM
GUIDANCE...STILL 4-7" AMOUNTS WILL BE POSSIBLE OVER NEARLY ALL OF
THE SAN LUIS VALLEY AND MOST OF THE PLAINS GENERALLY SOUTH OF
HIGHWAY 50 AND WEST OF SPRINGFIELD.
THE SANGRES...WETS AND SAN JUANS SHOULD DO VERY WELL WITH THIS
EVENT...WITH 12-18" OVER THE SAN JUANS AND NEAR A FOOT OVER THE
SANGRES AND WETS.
FARTHER NORTH LESS SNOW IS LIKELY AND HAVE CUT BACK ON AMOUNTS IN
THE CENTRAL MOUNTAINS. HAVE ALSO DOWNGRADED WARNINGS TO ADVISORIES
FOR PARTS OF THE CENTRAL MOUNTAIN REGION.
THE PIKES PEAK REGION WILL SEE ON AND OF SNOW SHOWERS WITH 1-3"
POSSIBLE THROUGH THE PERIOD. THE BEST CHANCE OF SNOW MAY OCCUR LATER
TOMORROW AS THE BAND LIFTS A BIT TO THE NORTH. HOWEVER THE SNOW IS
EXPECTED TO BE DECREASING AS THE FRONTOGENETICAL FORCING LESSENS
WITH TIME.
TOMORROW WILL BE ANOTHER COLD DAY WITH HIGHS ON THE 20S ALL AREAS.
WE MAY SEE SOME BREAKS IN THE CLOUDS LATE IN THE DAY OVER THE
NORTHERN PARTS OF THE CWA. /HODANISH
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 248 PM MST THU NOV 21 2013
...SNOW AND COLD CONTINUES...
FRIDAY NIGHT-SATURDAY...SNOW ACROSS THE EASTERN PLAINS WILL SLOWLY
WIND DOWN BETWEEN 06Z-09Z EARLY SATURDAY MORNING ACROSS THE EASTERN
PLAINS AS THE BEST LIFT MOVES AWAY FROM THE AREA.
ATTENTION THEN TURNS TO THE CUT OFF LOW SPINNING OVER SOUTHERN
CALIFORNIA. THE GFS AND THE NAM ARE IN SOMEWHAT BETTER AGREEMENT
WITH THE EC MODELS HANDLING OF THE LOW AND AM NOW MORE CONFIDENT THE
LOW WILL TAKE A MORE NORTHERLY TRACK THEN PREVIOUS GFS FORECASTS
HAVE SHOWN. IN COORDINATION WITH DDC/GLD/GJT I HAVE INCREASED POPS
ACROSS ALL OF THE MOUNTAIN AREAS SATURDAY AND SUNDAY...AND ACROSS
THE PLAINS ON SUNDAY. IF CURRENT MODEL TRENDS CONTINUE...I AM FAIRLY
CERTAIN THE WINTER STORM WARNING FOR THE SAN JUANS WILL NEED TO BE
EXTENDED THROUGH AT LEAST SATURDAY EVENING. THE 18Z NAM12 SHOWS 30
INCHES OF SNOWFALL BETWEEN 00Z SATURDAY AND 12Z SUNDAY ACROSS THE
SAN JUANS. THE 12Z GFS PAINTS 20 INCHES DURING THE SAME TIME FRAME.
TOO EARLY TO EXTEND THE WARNING AT THIS TIME.
SUNDAY...AS SNOW CHANCES REMAIN HIGH ALONG THE CONTINENTAL
DIVIDE...MODELS DIFFER ON HOW MUCH SNOW WILL FALL ACROSS THE EASTERN
MOUNTAINS AND THE PLAINS ON SUNDAY. THE GFS/NAM12 SHOW A
VORT MAX ROTATING AROUND THE CUTOFF LOW BETWEEN 09Z-12Z SUNDAY
MORNING...AND PUSHING IT THROUGH THE EASTERN PLAINS. THE GFS IS MUCH
WEAKER WITH THIS FEATURE AND SHOWS NO MORE THEN A DUSTING OF SNOW
ACROSS THE PLAINS...3 TO 6 INCHES IN THE WET MOUNTAINS AND THE
SANGRES THROUGH 00Z MONDAY. THE NAM SHOWS ALMOST A FOOT OF SNOW
ACROSS THE SAME MOUNTAIN ZONES AND UP TO 3 INCHES ALONG THE HIGHWAY
50 CORRIDOR EAST OF PUB (LAA/LHX). I HAVE TAKEN THE MORE
CONSERVATIVE GFS ROUTE AT THIS TIME...INCREASING POPS AND SNOW
AMOUNTS SLIGHTLY. HIGHLIGHT CRITERIA MAY BE REACHED IN THE
SANGRES/WETS IF THE NAM SOLUTION VERIFIES.
MONDAY-THURSDAY...MODELS DRY OUT THE FORECAST AREA RATHER QUICKLY
MONDAY...WITH ONLY A FEW REMAINING SNOW SHOWERS MONDAY MORNING. WEST
AND NORTHWEST FLOW WILL KEEP THE AREA DRY THROUGHOUT THE PERIOD.
500MB AND 700MB WINDS TURN MORE WEST AND SOUTHWEST LATE WEDNESDAY
THROUGH THURSDAY AHEAD OF ANOTHER PACIFIC STORM SYSTEM. TEMPERATURES
WILL REBOUND BACK TO AVERAGE LEVELS AS WELL. -PJC
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 248 PM MST THU NOV 21 2013
A SNOW BAND WILL DEVELOP OVER SOUTHERN COLORADO LATER THIS AFTERNOON
AND LAST INTO TOMORROW. THE HEAVIEST SNOW WILL FALL GENERALLY ALONG
AND SOUTH OF HIGHWAY 50. KALS WILL BE IMPACTED WITH SIGNIFICANT
ACCUMULATING SNOW LIKELY...WITH UP TO 6" POSSIBLE. SNOW WILL BEGIN
AT KALS THIS EVENING...~03Z...AND LAST INTO TOMORROW.
KPUB WILL BE ON THE NORTHERN GRADIENT BUT STILL EXPECT 1-3" OF
ACCUMULATING SNOW TONIGHT INTO TOMORROW.
KCOS WILL SEE MUCH SNOW...BUT LOW CIGS WILL LIKELY LAST THROUGH
TOMORROW. THE BEST CHANCE FORM SOME ACCUMULATING SNOW MAY ACTUALLY
BE TOMORROW AFTERNOON AS THE BAND LIFTS A BIT TO THE NORTH.
GIVEN THE CURRENT GUIDANCE...ALL AIRPORTS...KCOS...KALS AND KPUB
WILL SEE IFR CONDITIONS FORM MOST IF NOT ALL OF THE NEXT 24H.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 PM MST FRIDAY FOR COZ062-063-
076>078-083-086-089-093-097>099.
WINTER WEATHER ADVISORY UNTIL 6 PM MST FRIDAY FOR COZ058-059-061-
064.
WINTER STORM WARNING UNTIL 6 PM MST FRIDAY FOR COZ069>075-079-
080-087-088-094.
WINTER STORM WARNING UNTIL 6 PM MST FRIDAY FOR COZ060-065>068.
&&
$$
UPDATE...KT
SHORT TERM...HODANISH
LONG TERM...PJC
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
420 AM EST FRI NOV 22 2013
.DISCUSSION...
...HIGH RISK OF RIP CURRENTS AT THE ATLANTIC BEACHES TODAY...
...STRONG FRONT WILL BRING HAZARDOUS MARINE CONDITIONS AND ROUGH AND
POUNDING SURF SUNDAY AND MONDAY...
TODAY AND TONIGHT...LOW LEVEL CONVERGENCE IN COMBINATION WITH STOUT
EASTERLY FLOW CONTINUES TO PRODUCE BANDS OF SHOWERS ACROSS THE
ATLANTIC. AMPLE MOISTURE...ESPECIALLY IN THE LOWER LEVELS...WILL
PROMOTE SCATTERED RAIN COVERAGE MAINLY ALONG THE TREASURE COAST
THROUGH THIS MORNING.
WHILE THURSDAY EVENING`S SOUNDINGS STILL INDICATE A RATHER MOIST LOW
LEVEL ENVIRONMENT ACROSS THE STATE (PWATS ~1.6" TO 1.9")...WE ARE
EXPECTING THAT TO CHANGE OVER THE NEXT 12 HOURS. LATEST RUC ANALYSIS
ALONG WITH TONIGHT`S MODEL RUNS INDICATE A POCKET OF RELATIVELY DRY
AIR WORKING ITS WAY CLOSER TO THE PENINSULA. DRYING IN THE
1000-700MB LAYER COMBINED WITH WEAK RIDGING ALOFT SHOULD ALLOW FOR A
MARKED DECREASE IN SHOWER ACTIVITY TODAY COMPARED TO YESTERDAY. THE
DRY AIR WILL WORK ITS WAY INTO THE AREA FROM NORTH TO SOUTH...SO
HIGHER RAIN CHANCES (30-40 PERCENT) EXIST ACROSS THE TREASURE COAST
AND OKEECHOBEE COUNTY.
ONSHORE FLOW SHOULD KEEP TEMPERATURES IN THE UPPER 70S/NEAR 80
CLOSER TO THE COAST...BUT WITH LESS CLOUD COVER THAN TODAY...AM
EXPECTING IT TO FEEL WARMER. ADVERTISING LOW 80S ACROSS THE INTERIOR
FOR THIS AFTERNOON.
SATURDAY...THE SFC RIDGE WILL SETTLE SOUTH AND EXTEND OFFSHORE FROM
NE FL ON SAT. THIS WILL ALLOW FOR WEAKENING ONSHORE FLOW AND A
RATHER DRY AIRMASS SOUTH OF THE LOW LVL RIDGE AXIS ACROSS E CENTRAL
FL. PWAT VALUES ARE FORECAST AROUND 1.2 INCHES WITH AFTERNOON HIGHS
EXPECTED IN THE LOWER 80S. AREA SHOULD REMAIN DRY WITH THE ONLY
HAZARD EXPECTED TO BE AN ENHANCED RIP CURRENT RISK AT THE BEACHES.
SATURDAY NIGHT...A SPRAWLING HIGH PRESSURE CENTER MOVING SE THROUGH
THE MIDWEST WILL ALLOW ANOTHER COLD FRONT TO MOVE SOUTH INTO CENTRAL
FLORIDA SAT NIGHT. BREEZY TO WINDY CONDITIONS ARE EXPECTED TO
DEVELOP ALONG THE VOLUSIA AND BREVARD COUNTY COASTS WITH
STRENGTHENING N/NNE LOW LVL FLOW AFTER MIDNIGHT. A FRONTAL CLOUD
BAND WILL BRING MOSTLY CLOUDY SKIES TO NRN SECTIONS AND A SLGT CHC
FOR SHOWERS ALONG THE COAST. LOWS WILL RANGE FROM 60 ACROSS LAKE
COUNTY TO THE UPPER 60S ALONG THE TREASURE COAST.
SUNDAY...THE FRONT WILL SWEEP TWD S FL WITH WINDY NE WINDS EXPECTED
AS THE SFC HIGH PRESSURE AREA BUILDS TOWARD THE OHIO VALLEY AND SE
STATES. BAND OF FRONTAL CLOUD COVER START ACROSS THE NRN AREAS AND
MOVE SOUTH THROUGH THE DAY. EXPECT ISOLATED TO SCATTERED ATLANTIC
SHOWERS TO MOVE ONSHORE IN THE VERY STRONG LOW LVL NE FLOW AND PUSH
INTO THE INTERIOR INTO THE AFTERNOON. WINDY CONDITIONS WILL LIKELY
REQUIRE A LAKE WIND OR WIND ADVISORY ACROSS THE AREA. NE WINDS OF 20
TO 25 MPH WITH GUSTS TO 30 TO 35 MPH. HIGHS WILL BE MUCH COOLER THAN
SATURDAY IN THE MID TO UPPER 60S NRN ZONES TO THE MID 70S ACROSS
OKEECHOBEE COUNTY AND THE TREASURE COAST. HAZARDOUS SURF IS EXPECTED
TO DEVELOP AT THE BEACHES INTO THE AFTERNOON HOURS WITH LARGE
BREAKING WAVES DEVELOPING.
MONDAY...THE HIGH CENTER WILL SHIFT TOWARD THE MID ATLC ON MONDAY
KEEPING BREEZY TO WINDY EASTERLY FLOW ACROSS THE AREA. THERE WILL BE
SOME MID LVL DRYING BUT PROBABLY ENOUGH LOW LVL MOISTURE FOR SOME
ISOLATED ATLC SHOWERS TO CONTINUE TO MOVE ONSHORE. HIGHS WILL RANGE
FROM AROUND 70 NORTH TO THE MID 70S SRN AREAS. ROUGH SURF AND THE
RISK FOR RIP CURRENTS IS EXPECTED AT THE BEACHES.
TUESDAY-WEDNESDAY NIGHT...A PROGRESSIVE MID LVL S/W TROUGH EJECTING
FROM THE SRN PLAINS ACROSS THE SE STATES AND THEN TWD THE MID ATLC
WILL INDUCE A SFC LOW TO DEVELOP AND MOVE FROM SE LA TO THE FL
PANHANDLE AND NE ALONG THE SE ATLC COAST. THIS SYSTEM WILL VEER THE
LOW LVL FLOW FROM ESE TO SOUTHERLY ON TUESDAY AND BEGIN TO DRAW
DEEPER MOISTURE ACROSS THE FLORIDA PENINSULA BY TUE AFTERNOON. E
CENTRAL FL WILL BE IN THE WARM SECTOR BY THE AFTERNOON HOURS ON
TUESDAY WITH A FRONT APPROACHING THE AREA LATE TUE NIGHT OR EARLY
WEDNESDAY. SCATTERED SHOWERS SHOULD DEVELOP TUE AFTN INTO TUE NIGHT
WITH THE CHANCE FOR LIGHTNING STORMS TUE AFTN AND ALSO TUE NIGHT
AHEAD OF THE ADVANCING FRONT. 00Z GFS/ECMWF SWEEP THE FRONT ACROSS
THE AREA BY WED MORNING WITH BREEZY WNW/NW FLOW AND DEEP LAYER
DRYING TAKING HOLD WED AFTERNOON WITH FALLING TEMPERATURES AFTER THE
FRONTAL PASSAGE LATE IN THE DAY. AFTER A WARM DAY WITH HIGHS AROUND
80 TUESDAY AND LOWS IN THE 60S TUE NIGHT EXPECT COOLER TEMPS BY WED
NIGHT IN THE 50S BEHIND THE FRONT.
THANKSGIVING DAY INTO FRIDAY...HIGH PRESSURE WILL BUILD TOWARD THE
MID ATLC THROUGH LATE WEEK WITH BREEZY NE LOW LVL FLOW ON
THANKSGIVING DAY BEHIND THE FRONT ALLOWING FOR ISOLATED SHOWERS TO
MOVE ONSHORE ALONG THE COAST. HIGHS WILL COOL TO AROUND 70 AND THE
MID 70S SOUTH. FOR FRIDAY...HIGH PRESSURE NEAR THE MID ATLC WILL
ALLOW FOR BREEZY EASTERLY FLOW AND ISOLATED SHOWERS MOVING ONSHORE
FROM THE ATLANTIC AND MOVING INTO THE INTERIOR. HIGHS IN THE LOWER
70S NORTH TO MID-UPPER 70S SOUTH.
&&
.AVIATION...
EXPECTING LESS IN THE WAY OF SHOWER COVERAGE TODAY COMPARED TO
YESTERDAY AS DRIER AIR FILTERS DOWN THE PENINSULA. CIGS BETWEEN
FL050-080 LIKELY THIS MORNING. EASTERLY FLOW WILL KEEP THE CHANCE OF
BRIEF MVFR CIGS IN SHOWERS ALONG COASTAL SITES (MAINLY
KMLB-KVRB-KFPR-KSUA).
&&
.MARINE...
TODAY AND TONIGHT...BUOY 41009 STILL SHOWING 15-20KTS SUSTAINED AND
SEAS OF 7-8 FEET. EAST WINDS 15-20KTS ANTICIPATED THROUGH
TONIGHT...KEEPING SEAS ELEVATED (5-7FT NEARSHORE...7-9FT OFFSHORE).
SMALL CRAFT ADVISORY REMAINS IN EFFECT THROUGH 21Z.
WINDS SHOULD BEGIN TO LESSEN THIS EVENING AS OUR LOCAL PRESSURE
GRADIENT SLACKENS. SEAS WILL BE SLOWER TO RESPOND. WILL GO WITH AN
ADVISORY FOR SEAS THROUGH LATE TONIGHT (03Z SATURDAY) ACROSS OUR
OFFSHORE ZONES AND NEARSHORE WATERS SOUTH OF SEBASTIAN INLET.
SATURDAY...WINDS WILL DECREASE FROM THE ENE TO 5-10 KNOTS WITH A
RESIDUAL SWELL OF 4-6 FT. A STRONG FRONT WILL SWEEP ACROSS THE
WATERS LATE EARLY SUNDAY...INCREASING NNE WINDS TO AROUND 25 KNOTS
WITH GUSTS TO 35 KNOTS. SEAS WILL BUILD RAPIDLY AND REACH OVER 10
FEET IN THE GULF STREAM BY SUNDAY AFTERNOON AND SUNDAY NIGHT. THIS
WILL MAKE CONDITIONS VERY HAZARDOUS FOR SMALL CRAFT. CONDITIONS MAY
APPROACH GALE CRITERIA ON SUNDAY AFTERNOON-SUNDAY NIGHT. SOLID
ADVISORY CONDITIONS TO CONTINUE INTO EARLY NEXT WEEK AS FLOW VEERS
WITH WINDS TO 20-25 KNOTS MONDAY AND TUESDAY. NEXT COLD FRONT EARLY
WEDNESDAY WILL BRING A WIND SHIFT TO THE NORTHWEST BY WED AFTERNOON.
ALL IN ALL...SATURDAY LOOKS TO BE THE LAST SOMEWHAT FAVORABLE
BOATING DAY WITH STRONG WIND AND HAZARDOUS SEAS EXPECTED SUNDAY INTO
INTO THE MIDDLE OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 81 62 81 61 / 10 10 10 20
MCO 83 62 83 62 / 10 10 10 10
MLB 81 68 82 68 / 20 10 10 20
VRB 82 67 82 67 / 30 10 10 20
LEE 82 61 82 60 / 10 10 10 10
SFB 83 62 83 62 / 10 10 10 10
ORL 82 63 83 63 / 10 10 10 10
FPR 81 66 82 65 / 30 10 10 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR COASTAL
WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE
OUT 20 NM-COASTAL WATERS FROM SEBASTIAN INLET TO JUPITER
INLET OUT 20 NM-COASTAL WATERS FROM VOLUSIA BREVARD COUNTY
LINE TO SEBASTIAN INLET OUT 20 NM-WATERS FROM FLAGLER BEACH
TO VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS
FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE-
WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET
20 TO 60 NM OFFSHORE.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM THIS AFTERNOON
TO 10 PM EST THIS EVENING FOR COASTAL WATERS FROM SEBASTIAN
INLET TO JUPITER INLET OUT 20 NM-WATERS FROM FLAGLER BEACH
TO VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS
FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE-
WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET
20 TO 60 NM OFFSHORE.
&&
$$
SHORT TERM/AVIATION...ULRICH
LONG TERM....VOLKMER
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
202 PM CST FRI NOV 22 2013
.DISCUSSION...
335 AM CST
THE MAIN FORECAST CONCERNS THIS MORNING WILL FOCUS ON THE ARCTIC AIR
EXPECTED TO SPILL IN ACROSS THE AREA ON SATURDAY AND SUNDAY.
THE FIRST OF TWO COLD FRONTS HAS PUSHED ACROSS THE AREA OVERNIGHT.
HOWEVER...LIGHT PRECIPITATION CONTINUES ON THE BACK SIDE OF THIS
FRONT IN ASSOCIATION WITH SOME FORCING FOR ASCENT FROM SEVERAL WEAK
MID LEVEL SHORT WAVE DISTURBANCES...WHICH ARE BEING EJECTED EASTWARD
ACROSS THE MIDDLE MISSISSIPPI VALLEY WITHIN A RAPIDLY STRENGTHENING
120+ KT WESTERLY UPPER LEVEL JET. THIS DISTURBED MID LEVEL FLOW...IN
COMBINATION WITH SOME ENHANCED LOWER LEVEL FRONTOGENESIS ASSOCIATED
WITH THE BAROCLINIC ZONE DROPPING ACROSS THE AREA WILL LIKELY
CONTINUE TO PRODUCE SOME LIGHT PRECIP ACROSS THE AREA THROUGH MID TO
LATE MORNING.
IT APPEARS THAT COLDER AIR WILL WILL ARRIVE IN TIME TO LEAD TO A
CHANGE OVER TO SOME LIGHT SNOW EARLY THIS MORNING BEFORE THE PRECIP
ENDS. THE BEST CHANCES FOR THIS TO OCCUR LOOKS TO REMAIN MAINLY
ALONG AND NORTHEAST OF A LINE FROM NEAR PONTIAC NORTHEASTWARD
THROUGH CHICAGO. REGIONAL RADAR IMAGERY ACROSS EASTERN IOWA...WHERE
SNOW IS NOW FALLING INDICATES THAT THE PRECIP IS LIGHT...WITH ONLY A
FEW SLIGHTLY HEAVIER POCKETS OF SNOW EMBEDDED. I EXPECT THESE TRENDS
TO SHIFT OVER NORTHERN ILLINOIS THROUGH THE MORNING. SNOW SHOULD
BEGIN FALLING IN OR NEAR ROCKFORD AND MUCH OF NORTH CENTRAL ILLINOIS
BY AROUND 11 TO 12 UTC...AND IN THE CHICAGO AREA AFTER 13- 14 UTC.
PLACES TO THE SOUTHEAST ACROSS NORTHWESTERN INDIANA AND EAST CENTRAL
ILLINOIS WILL LIKELY REMAIN IN THE FORM OF RAIN. OVERALL...THIS
SHOULD NOT BE A BIG DEAL AS THE SNOW WILL REMAIN LIGHT AND
TEMPERATURES WILL LIKELY HOVER AROUND OR JUST ABOVE FREEZING THROUGH
THE MORNING. THEREFORE...NO REAL ACCUMULATION IS EXPECTED.
THINGS WILL DRY OUT BY THIS AFTERNOON...THEN ATTENTION TURNS TO THE
NEXT ARCTIC FRONT...WHICH SHOULD DROP ACROSS THE AREA EARLY ON
SATURDAY. THIS FRONT WILL MARK A QUICK SHIFT TO MUCH MUCH COLDER AIR
AS AN IMPRESSIVE 1048+ MB HIGH BUILDS SOUTHWARD ACROSS THE DAKOTAS.
TEMPERATURES AT 850 MB ARE PROGGED TO DROP DOWN AROUND -18 CELSIUS
ACROSS FAR NORTHERN ILLINOIS BY SATURDAY AFTERNOON VIA SOME STIFF
NORTHWESTERLY WINDS. OVERALL THIS WILL RESULT IN AN UGLY DAY...WITH
TEMPERATURES LIKELY REMAINING NEARLY STEADY OR EVEN DROPPING IN THE
20S THROUGH THE DAY. THIS COMBINED WITH A NORTHWEST WINDS OF 15 TO
25 MPH AND GUSTS UP TO 35 MPH WILL CREATE WIND CHILL VALUES IN THE
UPPER SINGLE DIGITS NORTH TO THE MID TO UPPER TEENS SOUTH. THE RAPID
TRANSITION TO THIS COLDER AIRMASS COULD EVEN SQUEEZE OUT A FEW
FLURRIES EARLY SATURDAY...MAKING IT FEEL MORE LIKE
MID-WINTER.
THESE VERY COLD TEMPERATURES WILL ALSO SET UP VERY FAVORABLE
THERMODYNAMIC CONDITIONS OVER LAKE MICHIGAN TO RESULT IN LAKE EFFECT
SNOW SATURDAY AND SATURDAY NIGHT. EQUILIBRIUM HEIGHTS ARE EXPECTED TO
TOP 12,000 FEET...AS LAKE TO 850 MB TEMPERATURE DEVIATIONS CLIMB IN
EXCESS OF 22 DEGREES CELSIUS. THIS SHOULD ULTIMATELY LEAD TO THE
POSSIBILITIES FOR SOME DECENT LAKE EFFECT SNOW. AT THIS TIME IT
APPEARS THAT THE NORTHWEST FLOW OVER LAKE MICHIGAN WILL FAVOR AREAS
ACROSS THE EASTERN SHORES...LIKELY EAST OF PORTER COUNTY INDIANA AS
WELL. I DID...HOWEVER...LEAVE SOME SLIGHT CHANCE MENTIONS FOR SNOW
SHOWERS FOR FAR NORTHEASTERN PORTER LATE SATURDAY AND SATURDAY
NIGHT.
SATURDAY NIGHT INTO SUNDAY MORNING APPEARS TO BE ONE OF THE COLDEST
NIGHTS THUS FAR THIS SEASON. GUIDANCE CONTINUES TO BUILD THE STRONG
1040 MB HIGH RIGHT ACROSS THE MID MISSISSIPPI VALLEY BY DAYBREAK
SUNDAY. ALTHOUGH THIS LOOKS TO RESULT IN ENOUGH OF A GRADIENT TO
KEEP SOME NORTHERLY WINDS GOING ACROSS NORTHEASTERN ILLINOIS AND
NORTHWESTERN INDIANA INTO SUNDAY MORNING...IT APPEARS THAT
TEMPERATURES WILL LIKELY FALL INTO THE SINGLE DIGITS IN SOME OF THE
COLDER SPOTS OF THE FOX VALLEY AND PORTIONS OF NORTH CENTRAL
ILLINOIS. IT APPEARS THAT EVEN THE CITY OF CHICAGO WILL DROP INTO
THE MID TEENS SUNDAY MORNING.
THIS COLD START TO SUNDAY WILL LIKELY ONLY ALLOW TEMPS TO REBOUND
INTO THE MIDDLE TO PERHAPS UPPER 20S SUNDAY AFTERNOON. THE SURFACE
FLOW SHOULD TURN SOUTHWESTERLY SUNDAY AFTERNOON AS THE SURFACE HIGH
CONTINUES TO SHIFT SOUTHEASTWARD TOWARDS THE TENNESSEE VALLEY. WIND
SPEEDS WILL LIKELY INCREASE SUNDAY NIGHT INTO MONDAY...SO THIS
SHOULD NOT ALLOW TEMPS TO DROP OFF MUCH SUNDAY NIGHT.
THE EXTENDED PERIOD APPEARS TO BE MAINLY DRY ACROSS THE REGION.
HOWEVER...THERE COULD BE SOME LIGHT SNOW ACROSS THE AREA ON MONDAY
AS GOOD ISENTROPIC ASCENT SETS UP ACROSS THE AREA IN ASSOCIATION
WITH A CLIPPER SYSTEM EXPECTED TO PUSH ACROSS SOUTHERN ONTARIO. I AM
NOT TO EXCITED ABOUT THIS CHANCE AS THE BEST DYNAMICS SHOULD REMAIN
NORTH OF THE AREA...BUT I HAVE LEFT SLIGHT CHANCE MENTIONS IN THE
FORECAST.
ANOTHER REINFORCING SHOT OF COLD AIR LOOKS TO DROP DOWN IN THE WAKE
OF THIS CLIPPER SYSTEM FOR MID WEEK...SO NO BIG IMPROVEMENTS IN
TEMPERATURES ARE EXPECTED. WITH THIS NEXT COLD PUSH...ANOTHER
SURFACE HIGH WILL LIKELY SHIFT SOUTHEAST SOMEWHERE ACROSS THE GREAT
LAKES ON OR AROUND THANKSGIVING. THE NORTHERLY FLOW THIS SETS UP
COULD PRODUCE SOME MORE LAKE EFFECT SNOW...AND IF THE FLOW TURNS
NORTHEAST AS THE GUIDANCE SUGGESTS BY THURSDAY...SOME OF THIS LAKE
EFFECT SNOW COULD AFFECT PORTIONS OF NORTHEASTERN ILLINOIS BEFORE IT
FADES. THIS IS STILL FAR OUT...BUT THE OVERALL SET UP FOR GOOD LAKE
EFFECT SNOW MAY NOT BE AS GOOD...ESPECIALLY BY THANKSGIVING...AS IT
APPEARS WARMER MID LEVEL TEMPERATURES MAY TRY TO QUICKLY OVERSPREAD
THE AREA IN RESPONSE TO RISING HEIGHTS ALOFT LATER NEXT WEEK. THIS
COULD ULTIMATELY LIMIT THE HEIGHT OF THE EQUILIBRIUM LEVELS FOR
PARCELS MODIFIED BY LAKE MICHIGAN. THIS WILL NEED TO BE WATCHED.
OTHERWISE IT JUST LOOKS UNSEASONABLY COLD AND DRY ACROSS MUCH OF THE
AREA THROUGH THANKSGIVING.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* PATCHY MVFR CIGS 2200-2500 FT DISSIPATING BY LATE AFTERNOON.
* GUSTY NORTH WINDS 15-20 KT EARLY THIS AFTERNOON DIMINISHING BY
EVENING.
* STRONG COLD FRONTAL PASSAGE EARLY SATURDAY MORNING. GUSTY NORTH-
NORTHWEST WINDS 25-30 KT. MVFR CIGS 2500-3000 FT DEVELOPING
BEHIND FRONT WITH A FEW SNOW FLURRIES.
RATZER
//DISCUSSION...UPDATED 18Z...
DRYING/SUBSIDENCE ERODING CLOUD COVER FROM THE NORTH-NORTHWEST
EARLY THIS AFTERNOON. MVFR CIGS HAVE SHOWN SLOW BUT STEADY
IMPROVEMENT...AND SHOULD CONTINUE TO LIFT/SCATTER TO VFR BY MID-
AFTERNOON. NORTH WINDS GUSTING 15-20 KT WILL GRADUALLY DECREASE
LATER THIS AFTERNOON...DROPPING TO LESS THAN 10 KT AFTER SUNSET AS
WEAK HIGH PRESSURE RIDGE DEVELOPS ACROSS THE TERMINALS.
LOW PRESSURE OVER SOUTHERN ONTARIO WILL DEEPEN AS IT MOVES
SOUTHEAST ACROSS THE NORTHERN GREAT LAKES TONIGHT...WITH A STRONG
ARCTIC COLD FRONT PUSHING SOUTHEAST ACROSS THE MIDWEST EARLY
SATURDAY. AFTER BACKING MORE WESTERLY OVERNIGHT...WINDS WILL VEER
NORTH-NORTHWEST AND GUST 25-30 KT BEHIND THE FRONT AFTER 10-13Z.
STRONG COLD ADVECTION WILL PRODUCE A FAIRLY SOLID MVFR STRATOCU
DECK WHICH LOOKS TO BE AROUND 2500 FT INITIALLY PERHAPS LIFTING
CLOSER TO 3000 FT IN THE AFTERNOON. WHILE NO ORGANIZED
PRECIPITATION IS EXPECTED...THE STRATOCU DECK WILL LIKELY PRODUCE
SOME FLURRIES AS THE COLUMN COOLS DURING THE DAY SATURDAY.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN CIGS ABOVE 2000 FT AND TRENDING TO VFR
CONDITIONS BY EVENING.
* HIGH CONFIDENCE IN WIND TRENDS AND GUSTY CONDITIONS SATURDAY.
* MEDIUM-HIGH CONFIDENCE IN MVFR CIGS SATURDAY.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT-SUNDAY...VFR.
MONDAY...CHC OF -SN AND MVFR.
TUESDAY- WEDNESDAY...VFR.
THURSDAY...SLIGHT CHANCE OF LAKE EFFECT SNOW SHOWERS.
MTF
&&
.MARINE...
204 AM CST
AN ACTIVE LATE AUTUMN/EARLY WINTER PATTERN WILL PREVAIL ACROSS THE
LAKE THROUGH AT LEAST THE FIRST HALF OF NEXT WEEK. A COLD FRONT
WHICH PASSED LATE THURSDAY NIGHT HAS USHERED IN STIFF NORTH TO
NORTHWEST WINDS OVER THE LAKE WHICH WILL CONTINUE THROUGH MIDDAY
BEFORE EASING AND BACKING. WHILE THERE MAY BE A TEMPORARY BREAK IN
SMALL CRAFT ADVISORY CRITERIA TONIGHT...IT IS EXPECTED TO BE
BRIEF...SO HAVE CONTINUED THAT HEADLINE FOR THE IL AND IN
NEARSHORE.
ANOTHER COLD FRONT IS SET TO CROSS THE LAKE LATE TONIGHT WHICH WILL
BRING A PUNCH OF EVEN COLDER AIR. THIS WILL LEAD TO STEEPER LAPSE
RATES AND GREATER TRANSFER OF WIND MOMENTUM. IN RESPONSE...NORTHWEST
GALES ARE EXPECTED TO QUICKLY SPREAD DOWN THE LAKE PRIOR TO DAYBREAK
ON SATURDAY. GALES LOOK DEFINITE...MAYBE A FEW TO EVEN 40 KT. GALES
MAY EVEN BE EXPERIENCED IN NEAR SHORE AREAS OF INDIANA GIVEN THE
GREATER COMPONENT OF ONSHORE WIND DIRECTION AND REALIZED FETCH. AS
FOR FREEZING SPRAY SATURDAY...IT CONTINUES TO LOOK POSSIBLE BUT
MAINLY LIGHT DUE TO TOO WARM OF WATER TEMPERATURES.
A LARGE AND STRONG CANADIAN HIGH WILL MOVE TO THE SOUTH OF THE LAKE
ON SUNDAY AND THE PRESSURE GRADIENT ON ITS BACKSIDE WILL BE ENHANCED
BY LOW PRESSURE RACING ACROSS CANADA ON SUNDAY NIGHT INTO EARLY
MONDAY. THIS WILL AGAIN SET THE STAGE FOR POTENTIAL GALES...THIS
TIME FROM THE SOUTHWEST/WEST. HIGH PRESSURE LOOKS TO SLOWLY BUILD IN
THROUGH THE MIDWEEK TIME FRAME THEN...WITH INCREASING POTENTIAL FOR
LAKE EFFECT SNOWS ON THE CENTRAL...EASTERN...AND SOUTHERN PARTS OF
THE LAKE.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 AM SATURDAY TO 9 PM
SATURDAY.
SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 9 AM SATURDAY.
GALE WATCH...LMZ744-LMZ745...9 AM SATURDAY TO 9 PM SATURDAY.
SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 9 PM
SATURDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
130 PM CST Fri Nov 22 2013
.DISCUSSION...
ISSUED 120 PM CST Fri Nov 22 2013
SHORT TERM...Tonight through Monday
Temperatures and wind chills the main forecast concern this period
as Arctic high pressure settles over the region.
Models in good agreement in the short term with respect to the track
of the surface high pressure through the Midwest with our western
areas seeing the coldest temps late Sat night into Sunday morning,
and then our far east and southeast may see their coldest early
morning readings early Monday morning. With the surface high forecast
just to our west Saturday night, north to northwest winds will hold
up enough to drop wind chills down close to zero. As the high settles
across our area on Sunday, winds will be much lighter so wind chills
won`t be as much of a factor until towards dawn Monday across our far
west and northwest areas as the return flow sets up.
Moisture streaming northeast from the cutoff low across the southwest
U.S. will move through our area tonight, especially across the south.
Overnight lows will range from the mid teens far northwest to the mid
20s far southeast. With a gusty northerly wind on Saturday, afternoon
temperatures will stuggle thru the mid 20s north the mid 30s south
with wind chills in the 10 to 15 degree range north and low 20s far
south. Lows early Sunday morning will dip into the 5 to 10 degree
range north to the low/mid teens far south with single digit wind
chills in most of our area.
LONG TERM...Tuesday through Friday
Cold pattern to hold through most of the week with minor warm ups
in advance of shortwaves approaching from the northwest about every
couple of days. Little in the way of significant rain or snow seen
as a cutoff low, currently over the southwest U.S., tracks across
the southern Plains and lower Mississippi Valley, keeping most of
the significant precip south of our I-70 corridor early next week.
Meanwhile, return flow ahead of a northern stream wave may generate
some warm advection snow/rain on Monday but with such dry air at
the low levels thanks to the departing Arctic high, have opted to
keep the pops out of our area on Monday for now. Another shot of
Arctic air will follow the northern stream shortwave late Tuesday
into Wednesday with 850 temps from both the operational GFS and
12z ECMWF showing -10 to -14 degrees C pouring south into our
area. If those numbers do verify late in the week, our going highs
and lows for Wed and Thu may be too optimistic.
Smith
&&
.AVIATION...
ISSUED 1140 AM CST Fri Nov 22 2013
IFR ceilings will linger at both KBMI and KCMI for the next hour
or two before slowly improving to MVFR for the balance of the
afternoon. Back edge of cloud cover remains across far northwest
Illinois into eastern Iowa and has shown little to no
southeastward progress over the past several hours. NAM forecast
soundings try to clear skies at KPIA too early, so have trended
toward the more pessimistic HRRR for this aviation forecast. As
such, have maintained MVFR ceilings until 23z at KPIA...and 01z
further southeast at the I-72 terminals. Once low clouds depart,
plenty of high cloudiness currently over the Plains will stream
eastward tonight. This high cloudiness will gradually settle
southward overnight, resulting in mostly sunny skies by Saturday
morning. Strong northwesterly winds gusting to around 20kt will
persist through the afternoon before subsiding to less than 10kt
this evening. The winds will once again increase after 15z
Saturday, with numeric guidance suggesting gusts to between 20 and
25kt.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1137 AM CST FRI NOV 22 2013
.DISCUSSION...
335 AM CST
THE MAIN FORECAST CONCERNS THIS MORNING WILL FOCUS ON THE ARCTIC AIR
EXPECTED TO SPILL IN ACROSS THE AREA ON SATURDAY AND SUNDAY.
THE FIRST OF TWO COLD FRONTS HAS PUSHED ACROSS THE AREA OVERNIGHT.
HOWEVER...LIGHT PRECIPITATION CONTINUES ON THE BACK SIDE OF THIS
FRONT IN ASSOCIATION WITH SOME FORCING FOR ASCENT FROM SEVERAL WEAK
MID LEVEL SHORT WAVE DISTURBANCES...WHICH ARE BEING EJECTED EASTWARD
ACROSS THE MIDDLE MISSISSIPPI VALLEY WITHIN A RAPIDLY STRENGTHENING
120+ KT WESTERLY UPPER LEVEL JET. THIS DISTURBED MID LEVEL FLOW...IN
COMBINATION WITH SOME ENHANCED LOWER LEVEL FRONTOGENESIS ASSOCIATED
WITH THE BAROCLINIC ZONE DROPPING ACROSS THE AREA WILL LIKELY
CONTINUE TO PRODUCE SOME LIGHT PRECIP ACROSS THE AREA THROUGH MID TO
LATE MORNING.
IT APPEARS THAT COLDER AIR WILL WILL ARRIVE IN TIME TO LEAD TO A
CHANGE OVER TO SOME LIGHT SNOW EARLY THIS MORNING BEFORE THE PRECIP
ENDS. THE BEST CHANCES FOR THIS TO OCCUR LOOKS TO REMAIN MAINLY
ALONG AND NORTHEAST OF A LINE FROM NEAR PONTIAC NORTHEASTWARD
THROUGH CHICAGO. REGIONAL RADAR IMAGERY ACROSS EASTERN IOWA...WHERE
SNOW IS NOW FALLING INDICATES THAT THE PRECIP IS LIGHT...WITH ONLY A
FEW SLIGHTLY HEAVIER POCKETS OF SNOW EMBEDDED. I EXPECT THESE TRENDS
TO SHIFT OVER NORTHERN ILLINOIS THROUGH THE MORNING. SNOW SHOULD
BEGIN FALLING IN OR NEAR ROCKFORD AND MUCH OF NORTH CENTRAL ILLINOIS
BY AROUND 11 TO 12 UTC...AND IN THE CHICAGO AREA AFTER 13- 14 UTC.
PLACES TO THE SOUTHEAST ACROSS NORTHWESTERN INDIANA AND EAST CENTRAL
ILLINOIS WILL LIKELY REMAIN IN THE FORM OF RAIN. OVERALL...THIS
SHOULD NOT BE A BIG DEAL AS THE SNOW WILL REMAIN LIGHT AND
TEMPERATURES WILL LIKELY HOVER AROUND OR JUST ABOVE FREEZING THROUGH
THE MORNING. THEREFORE...NO REAL ACCUMULATION IS EXPECTED.
THINGS WILL DRY OUT BY THIS AFTERNOON...THEN ATTENTION TURNS TO THE
NEXT ARCTIC FRONT...WHICH SHOULD DROP ACROSS THE AREA EARLY ON
SATURDAY. THIS FRONT WILL MARK A QUICK SHIFT TO MUCH MUCH COLDER AIR
AS AN IMPRESSIVE 1048+ MB HIGH BUILDS SOUTHWARD ACROSS THE DAKOTAS.
TEMPERATURES AT 850 MB ARE PROGGED TO DROP DOWN AROUND -18 CELSIUS
ACROSS FAR NORTHERN ILLINOIS BY SATURDAY AFTERNOON VIA SOME STIFF
NORTHWESTERLY WINDS. OVERALL THIS WILL RESULT IN AN UGLY DAY...WITH
TEMPERATURES LIKELY REMAINING NEARLY STEADY OR EVEN DROPPING IN THE
20S THROUGH THE DAY. THIS COMBINED WITH A NORTHWEST WINDS OF 15 TO
25 MPH AND GUSTS UP TO 35 MPH WILL CREATE WIND CHILL VALUES IN THE
UPPER SINGLE DIGITS NORTH TO THE MID TO UPPER TEENS SOUTH. THE RAPID
TRANSITION TO THIS COLDER AIRMASS COULD EVEN SQUEEZE OUT A FEW
FLURRIES EARLY SATURDAY...MAKING IT FEEL MORE LIKE
MID-WINTER.
THESE VERY COLD TEMPERATURES WILL ALSO SET UP VERY FAVORABLE
THERMODYNAMIC CONDITIONS OVER LAKE MICHIGAN TO RESULT IN LAKE EFFECT
SNOW SATURDAY AND SATURDAY NIGHT. EQUILIBRIUM HEIGHTS ARE EXPECTED TO
TOP 12,000 FEET...AS LAKE TO 850 MB TEMPERATURE DEVIATIONS CLIMB IN
EXCESS OF 22 DEGREES CELSIUS. THIS SHOULD ULTIMATELY LEAD TO THE
POSSIBILITIES FOR SOME DECENT LAKE EFFECT SNOW. AT THIS TIME IT
APPEARS THAT THE NORTHWEST FLOW OVER LAKE MICHIGAN WILL FAVOR AREAS
ACROSS THE EASTERN SHORES...LIKELY EAST OF PORTER COUNTY INDIANA AS
WELL. I DID...HOWEVER...LEAVE SOME SLIGHT CHANCE MENTIONS FOR SNOW
SHOWERS FOR FAR NORTHEASTERN PORTER LATE SATURDAY AND SATURDAY
NIGHT.
SATURDAY NIGHT INTO SUNDAY MORNING APPEARS TO BE ONE OF THE COLDEST
NIGHTS THUS FAR THIS SEASON. GUIDANCE CONTINUES TO BUILD THE STRONG
1040 MB HIGH RIGHT ACROSS THE MID MISSISSIPPI VALLEY BY DAYBREAK
SUNDAY. ALTHOUGH THIS LOOKS TO RESULT IN ENOUGH OF A GRADIENT TO
KEEP SOME NORTHERLY WINDS GOING ACROSS NORTHEASTERN ILLINOIS AND
NORTHWESTERN INDIANA INTO SUNDAY MORNING...IT APPEARS THAT
TEMPERATURES WILL LIKELY FALL INTO THE SINGLE DIGITS IN SOME OF THE
COLDER SPOTS OF THE FOX VALLEY AND PORTIONS OF NORTH CENTRAL
ILLINOIS. IT APPEARS THAT EVEN THE CITY OF CHICAGO WILL DROP INTO
THE MID TEENS SUNDAY MORNING.
THIS COLD START TO SUNDAY WILL LIKELY ONLY ALLOW TEMPS TO REBOUND
INTO THE MIDDLE TO PERHAPS UPPER 20S SUNDAY AFTERNOON. THE SURFACE
FLOW SHOULD TURN SOUTHWESTERLY SUNDAY AFTERNOON AS THE SURFACE HIGH
CONTINUES TO SHIFT SOUTHEASTWARD TOWARDS THE TENNESSEE VALLEY. WIND
SPEEDS WILL LIKELY INCREASE SUNDAY NIGHT INTO MONDAY...SO THIS
SHOULD NOT ALLOW TEMPS TO DROP OFF MUCH SUNDAY NIGHT.
THE EXTENDED PERIOD APPEARS TO BE MAINLY DRY ACROSS THE REGION.
HOWEVER...THERE COULD BE SOME LIGHT SNOW ACROSS THE AREA ON MONDAY
AS GOOD ISENTROPIC ASCENT SETS UP ACROSS THE AREA IN ASSOCIATION
WITH A CLIPPER SYSTEM EXPECTED TO PUSH ACROSS SOUTHERN ONTARIO. I AM
NOT TO EXCITED ABOUT THIS CHANCE AS THE BEST DYNAMICS SHOULD REMAIN
NORTH OF THE AREA...BUT I HAVE LEFT SLIGHT CHANCE MENTIONS IN THE
FORECAST.
ANOTHER REINFORCING SHOT OF COLD AIR LOOKS TO DROP DOWN IN THE WAKE
OF THIS CLIPPER SYSTEM FOR MID WEEK...SO NO BIG IMPROVEMENTS IN
TEMPERATURES ARE EXPECTED. WITH THIS NEXT COLD PUSH...ANOTHER
SURFACE HIGH WILL LIKELY SHIFT SOUTHEAST SOMEWHERE ACROSS THE GREAT
LAKES ON OR AROUND THANKSGIVING. THE NORTHERLY FLOW THIS SETS UP
COULD PRODUCE SOME MORE LAKE EFFECT SNOW...AND IF THE FLOW TURNS
NORTHEAST AS THE GUIDANCE SUGGESTS BY THURSDAY...SOME OF THIS LAKE
EFFECT SNOW COULD AFFECT PORTIONS OF NORTHEASTERN ILLINOIS BEFORE IT
FADES. THIS IS STILL FAR OUT...BUT THE OVERALL SET UP FOR GOOD LAKE
EFFECT SNOW MAY NOT BE AS GOOD...ESPECIALLY BY THANKSGIVING...AS IT
APPEARS WARMER MID LEVEL TEMPERATURES MAY TRY TO QUICKLY OVERSPREAD
THE AREA IN RESPONSE TO RISING HEIGHTS ALOFT LATER NEXT WEEK. THIS
COULD ULTIMATELY LIMIT THE HEIGHT OF THE EQUILIBRIUM LEVELS FOR
PARCELS MODIFIED BY LAKE MICHIGAN. THIS WILL NEED TO BE WATCHED.
OTHERWISE IT JUST LOOKS UNSEASONABLY COLD AND DRY ACROSS MUCH OF THE
AREA THROUGH THANKSGIVING.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* PATCHY MVFR CIGS 1600-2000 FT DISSIPATING EARLY THIS AFTERNOON.
* GUSTY NORTH WINDS 15-20 KT THIS AFTERNOON. GUSTS DIMINISHING BY
EARLY EVENING.
* STRONG COLD FRONTAL PASSAGE EARLY SATURDAY MORNING. GUSTY NORTH-
NORTHWEST WINDS 25-30 KT. MVFR CIGS 2500-3000 FT DEVELOPING
BEHIND FRONT WITH A FEW SNOW FLURRIES.
RATZER
//DISCUSSION...UPDATED 18Z...
DRYING/SUBSIDENCE ERODING CLOUD COVER FROM THE NORTH-NORTHWEST
EARLY THIS AFTERNOON. MVFR CIGS HAVE SHOWN SLOW BUT STEADY
IMPROVEMENT...AND SHOULD CONTINUE TO LIFT/SCATTER TO VFR BY MID-
AFTERNOON. NORTH WINDS GUSTING 15-20 KT WILL GRADUALLY DECREASE
LATER THIS AFTERNOON...DROPPING TO LESS THAN 10 KT AFTER SUNSET AS
WEAK HIGH PRESSURE RIDGE DEVELOPS ACROSS THE TERMINALS.
LOW PRESSURE OVER SOUTHERN ONTARIO WILL DEEPEN AS IT MOVES
SOUTHEAST ACROSS THE NORTHERN GREAT LAKES TONIGHT...WITH A STRONG
ARCTIC COLD FRONT PUSHING SOUTHEAST ACROSS THE MIDWEST EARLY
SATURDAY. AFTER BACKING MORE WESTERLY OVERNIGHT...WINDS WILL VEER
NORTH-NORTHWEST AND GUST 25-30 KT BEHIND THE FRONT AFTER 10-13Z.
STRONG COLD ADVECTION WILL PRODUCE A FAIRLY SOLID MVFR STRATOCU
DECK WHICH LOOKS TO BE AROUND 2500 FT INITIALLY PERHAPS LIFTING
CLOSER TO 3000 FT IN THE AFTERNOON. WHILE NO ORGANIZED
PRECIPITATION IS EXPECTED...THE STRATOCU DECK WILL LIKELY PRODUCE
SOME FLURRIES AS THE COLUMN COOLS DURING THE DAY SATURDAY.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN TREND TO VFR CONDITIONS THIS AFTERNOON. CIGS
STARTING OUT ABOVE 1500 FT.
* HIGH CONFIDENCE IN WIND TRENDS AND GUSTY CONDITIONS SATURDAY.
* MEDIUM-HIGH CONFIDENCE IN MVFR CIGS SATURDAY.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT-SUNDAY...VFR.
MONDAY...CHC OF -SN AND MVFR.
TUESDAY- WEDNESDAY...VFR.
THURSDAY...SLIGHT CHANCE OF LAKE EFFECT SNOW SHOWERS.
MTF
&&
.MARINE...
204 AM CST
AN ACTIVE LATE AUTUMN/EARLY WINTER PATTERN WILL PREVAIL ACROSS THE
LAKE THROUGH AT LEAST THE FIRST HALF OF NEXT WEEK. A COLD FRONT
WHICH PASSED LATE THURSDAY NIGHT HAS USHERED IN STIFF NORTH TO
NORTHWEST WINDS OVER THE LAKE WHICH WILL CONTINUE THROUGH MIDDAY
BEFORE EASING AND BACKING. WHILE THERE MAY BE A TEMPORARY BREAK IN
SMALL CRAFT ADVISORY CRITERIA TONIGHT...IT IS EXPECTED TO BE
BRIEF...SO HAVE CONTINUED THAT HEADLINE FOR THE IL AND IN
NEARSHORE.
ANOTHER COLD FRONT IS SET TO CROSS THE LAKE LATE TONIGHT WHICH WILL
BRING A PUNCH OF EVEN COLDER AIR. THIS WILL LEAD TO STEEPER LAPSE
RATES AND GREATER TRANSFER OF WIND MOMENTUM. IN RESPONSE...NORTHWEST
GALES ARE EXPECTED TO QUICKLY SPREAD DOWN THE LAKE PRIOR TO DAYBREAK
ON SATURDAY. GALES LOOK DEFINITE...MAYBE A FEW TO EVEN 40 KT. GALES
MAY EVEN BE EXPERIENCED IN NEAR SHORE AREAS OF INDIANA GIVEN THE
GREATER COMPONENT OF ONSHORE WIND DIRECTION AND REALIZED FETCH. AS
FOR FREEZING SPRAY SATURDAY...IT CONTINUES TO LOOK POSSIBLE BUT
MAINLY LIGHT DUE TO TOO WARM OF WATER TEMPERATURES.
A LARGE AND STRONG CANADIAN HIGH WILL MOVE TO THE SOUTH OF THE LAKE
ON SUNDAY AND THE PRESSURE GRADIENT ON ITS BACKSIDE WILL BE ENHANCED
BY LOW PRESSURE RACING ACROSS CANADA ON SUNDAY NIGHT INTO EARLY
MONDAY. THIS WILL AGAIN SET THE STAGE FOR POTENTIAL GALES...THIS
TIME FROM THE SOUTHWEST/WEST. HIGH PRESSURE LOOKS TO SLOWLY BUILD IN
THROUGH THE MIDWEEK TIME FRAME THEN...WITH INCREASING POTENTIAL FOR
LAKE EFFECT SNOWS ON THE CENTRAL...EASTERN...AND SOUTHERN PARTS OF
THE LAKE.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 AM SATURDAY TO 9 PM
SATURDAY.
SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 9 AM SATURDAY.
GALE WATCH...LMZ744-LMZ745...9 AM SATURDAY TO 9 PM SATURDAY.
SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 9 PM
SATURDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
1035 AM CST Fri Nov 22 2013
.DISCUSSION...
ISSUED 1035 AM CST Fri Nov 22 2013
Cold front continues to push eastward toward the Appalachians,
while gusty northwesterly winds bring much colder air into central
Illinois. Light showers/drizzle from earlier this morning has now
shifted into far eastern Illinois and will exit into Indiana over
the next couple of hours. Cloudy skies currently blanket the
entire area: however, clearing is noted as close as eastern Iowa.
Latest visible satellite imagery shows additional diurnal clouds
developing along the back edge of the main cloud deck, thus
slowing the eastward progression of the clearing. Despite this new
development, think skies will become partly to mostly sunny by mid
to late afternoon along and northwest of a Rushville to Minonk
line. Further southeast, cloudy skies will prevail throughout the
day. Temperatures will remain steady or slowly fall into the 30s.
Zone update to remove morning POPs and better define the clearing
trend has already been issued.
Barnes
&&
.AVIATION...
ISSUED 545 AM CST Fri Nov 22 2013
Ifr conditions over region in the post frontal area over central
IL. IR satellite and moisture channel depicts minor wave moving
through central IL with debris from the AR pcpn. Very light pcpn
with this wave is gradually moving eastward over eastern CWA.
Expect cigs to only slowly raise til mid morning and then improve.
Drier air finally moves in during afternoon per the HRRR models
and then show increase cigs. The patchy vsbs in fog to improve
early this morning to vfr.
Goetsch
&&
.PREV DISCUSSION...
ISSUED 220 AM CST Fri Nov 22 2013
The cold front has pushed through much of the forecast area early
this morning...and is about to clear the far southeast as of 2 am.
Some light post-frontal showers continue over the northwest half
of the area, while radar and surface obs showed some fairly
widespread light snow across much of central and eastern Iowa,
back where temperatures are mainly in the 20s. Have been seeing
some dense fog along and just behind the front, but this should
continue to lift as the front moves further east.
Main forecast concern involves the cold weekend weather, and
timing of the ending of the remaining precipitation today.
SHORT TERM...Today through Sunday:
Latest model trends continue to get the area largely dry by
midday. Colder air will make more of a surge later today, and most
areas should see steady or falling afternoon temperatures.
Arctic air mass over central Canada poised to surge southeast
through the Great Lakes this weekend. Brunt of the coldest air
still progged to stay to our north, but 850 mb temperatures drop
to around -14C here, so sub-freezing highs likely. Rather blustery
conditions expected Saturday ahead of strong Canadian high
pressure, but winds will subside on Sunday as the high drifts into
south central Illinois.
LONG TERM...Monday through Thanksgiving Day:
Large cutoff low, currently seen in water vapor imagery centered
near Los Angeles, should finally start to push eastward early next
week, as the deep trough in the northern stream finally pushes
to New England. Next shortwave in the northern stream is looking
to come through mainly dry Monday afternoon/night, as a storm
system develops along the Gulf. Deformation precipitation with
this system progged to reach about as far as the Ohio River as the
storm slowly moves into the Carolinas by midweek. This will
largely keep the Midwest dry from Tuesday through Thanksgiving,
except for some lake effect snow south of Lake Michigan. Second
Arctic surge at mid week is not quite as bitter as the upcoming
cold wave, but highs in the lower to mid 30s will be common for
the pre-Thanksgiving travel rush.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
801 AM CST FRI NOV 22 2013
.DISCUSSION...
335 AM CST
THE MAIN FORECAST CONCERNS THIS MORNING WILL FOCUS ON THE ARCTIC AIR
EXPECTED TO SPILL IN ACROSS THE AREA ON SATURDAY AND SUNDAY.
THE FIRST OF TWO COLD FRONTS HAS PUSHED ACROSS THE AREA OVERNIGHT.
HOWEVER...LIGHT PRECIPITATION CONTINUES ON THE BACK SIDE OF THIS
FRONT IN ASSOCIATION WITH SOME FORCING FOR ASCENT FROM SEVERAL WEAK
MID LEVEL SHORT WAVE DISTURBANCES...WHICH ARE BEING EJECTED EASTWARD
ACROSS THE MIDDLE MISSISSIPPI VALLEY WITHIN A RAPIDLY STRENGTHENING
120+ KT WESTERLY UPPER LEVEL JET. THIS DISTURBED MID LEVEL FLOW...IN
COMBINATION WITH SOME ENHANCED LOWER LEVEL FRONTOGENESIS ASSOCIATED
WITH THE BAROCLINIC ZONE DROPPING ACROSS THE AREA WILL LIKELY
CONTINUE TO PRODUCE SOME LIGHT PRECIP ACROSS THE AREA THROUGH MID TO
LATE MORNING.
IT APPEARS THAT COLDER AIR WILL WILL ARRIVE IN TIME TO LEAD TO A
CHANGE OVER TO SOME LIGHT SNOW EARLY THIS MORNING BEFORE THE PRECIP
ENDS. THE BEST CHANCES FOR THIS TO OCCUR LOOKS TO REMAIN MAINLY
ALONG AND NORTHEAST OF A LINE FROM NEAR PONTIAC NORTHEASTWARD
THROUGH CHICAGO. REGIONAL RADAR IMAGERY ACROSS EASTERN IOWA...WHERE
SNOW IS NOW FALLING INDICATES THAT THE PRECIP IS LIGHT...WITH ONLY A
FEW SLIGHTLY HEAVIER POCKETS OF SNOW EMBEDDED. I EXPECT THESE TRENDS
TO SHIFT OVER NORTHERN ILLINOIS THROUGH THE MORNING. SNOW SHOULD
BEGIN FALLING IN OR NEAR ROCKFORD AND MUCH OF NORTH CENTRAL ILLINOIS
BY AROUND 11 TO 12 UTC...AND IN THE CHICAGO AREA AFTER 13- 14 UTC.
PLACES TO THE SOUTHEAST ACROSS NORTHWESTERN INDIANA AND EAST CENTRAL
ILLINOIS WILL LIKELY REMAIN IN THE FORM OF RAIN. OVERALL...THIS
SHOULD NOT BE A BIG DEAL AS THE SNOW WILL REMAIN LIGHT AND
TEMPERATURES WILL LIKELY HOVER AROUND OR JUST ABOVE FREEZING THROUGH
THE MORNING. THEREFORE...NO REAL ACCUMULATION IS EXPECTED.
THINGS WILL DRY OUT BY THIS AFTERNOON...THEN ATTENTION TURNS TO THE
NEXT ARCTIC FRONT...WHICH SHOULD DROP ACROSS THE AREA EARLY ON
SATURDAY. THIS FRONT WILL MARK A QUICK SHIFT TO MUCH MUCH COLDER AIR
AS AN IMPRESSIVE 1048+ MB HIGH BUILDS SOUTHWARD ACROSS THE DAKOTAS.
TEMPERATURES AT 850 MB ARE PROGGED TO DROP DOWN AROUND -18 CELSIUS
ACROSS FAR NORTHERN ILLINOIS BY SATURDAY AFTERNOON VIA SOME STIFF
NORTHWESTERLY WINDS. OVERALL THIS WILL RESULT IN AN UGLY DAY...WITH
TEMPERATURES LIKELY REMAINING NEARLY STEADY OR EVEN DROPPING IN THE
20S THROUGH THE DAY. THIS COMBINED WITH A NORTHWEST WINDS OF 15 TO
25 MPH AND GUSTS UP TO 35 MPH WILL CREATE WIND CHILL VALUES IN THE
UPPER SINGLE DIGITS NORTH TO THE MID TO UPPER TEENS SOUTH. THE RAPID
TRANSITION TO THIS COLDER AIRMASS COULD EVEN SQUEEZE OUT A FEW
FLURRIES EARLY SATURDAY...MAKING IT FEEL MORE LIKE
MID-WINTER.
THESE VERY COLD TEMPERATURES WILL ALSO SET UP VERY FAVORABLE
THERMODYNAMIC CONDITIONS OVER LAKE MICHIGAN TO RESULT IN LAKE EFFECT
SNOW SATURDAY AND SATURDAY NIGHT. EQUILIBRIUM HEIGHTS ARE EXPECTED TO
TOP 12,000 FEET...AS LAKE TO 850 MB TEMPERATURE DEVIATIONS CLIMB IN
EXCESS OF 22 DEGREES CELSIUS. THIS SHOULD ULTIMATELY LEAD TO THE
POSSIBILITIES FOR SOME DECENT LAKE EFFECT SNOW. AT THIS TIME IT
APPEARS THAT THE NORTHWEST FLOW OVER LAKE MICHIGAN WILL FAVOR AREAS
ACROSS THE EASTERN SHORES...LIKELY EAST OF PORTER COUNTY INDIANA AS
WELL. I DID...HOWEVER...LEAVE SOME SLIGHT CHANCE MENTIONS FOR SNOW
SHOWERS FOR FAR NORTHEASTERN PORTER LATE SATURDAY AND SATURDAY
NIGHT.
SATURDAY NIGHT INTO SUNDAY MORNING APPEARS TO BE ONE OF THE COLDEST
NIGHTS THUS FAR THIS SEASON. GUIDANCE CONTINUES TO BUILD THE STRONG
1040 MB HIGH RIGHT ACROSS THE MID MISSISSIPPI VALLEY BY DAYBREAK
SUNDAY. ALTHOUGH THIS LOOKS TO RESULT IN ENOUGH OF A GRADIENT TO
KEEP SOME NORTHERLY WINDS GOING ACROSS NORTHEASTERN ILLINOIS AND
NORTHWESTERN INDIANA INTO SUNDAY MORNING...IT APPEARS THAT
TEMPERATURES WILL LIKELY FALL INTO THE SINGLE DIGITS IN SOME OF THE
COLDER SPOTS OF THE FOX VALLEY AND PORTIONS OF NORTH CENTRAL
ILLINOIS. IT APPEARS THAT EVEN THE CITY OF CHICAGO WILL DROP INTO
THE MID TEENS SUNDAY MORNING.
THIS COLD START TO SUNDAY WILL LIKELY ONLY ALLOW TEMPS TO REBOUND
INTO THE MIDDLE TO PERHAPS UPPER 20S SUNDAY AFTERNOON. THE SURFACE
FLOW SHOULD TURN SOUTHWESTERLY SUNDAY AFTERNOON AS THE SURFACE HIGH
CONTINUES TO SHIFT SOUTHEASTWARD TOWARDS THE TENNESSEE VALLEY. WIND
SPEEDS WILL LIKELY INCREASE SUNDAY NIGHT INTO MONDAY...SO THIS
SHOULD NOT ALLOW TEMPS TO DROP OFF MUCH SUNDAY NIGHT.
THE EXTENDED PERIOD APPEARS TO BE MAINLY DRY ACROSS THE REGION.
HOWEVER...THERE COULD BE SOME LIGHT SNOW ACROSS THE AREA ON MONDAY
AS GOOD ISENTROPIC ASCENT SETS UP ACROSS THE AREA IN ASSOCIATION
WITH A CLIPPER SYSTEM EXPECTED TO PUSH ACROSS SOUTHERN ONTARIO. I AM
NOT TO EXCITED ABOUT THIS CHANCE AS THE BEST DYNAMICS SHOULD REMAIN
NORTH OF THE AREA...BUT I HAVE LEFT SLIGHT CHANCE MENTIONS IN THE
FORECAST.
ANOTHER REINFORCING SHOT OF COLD AIR LOOKS TO DROP DOWN IN THE WAKE
OF THIS CLIPPER SYSTEM FOR MID WEEK...SO NO BIG IMPROVEMENTS IN
TEMPERATURES ARE EXPECTED. WITH THIS NEXT COLD PUSH...ANOTHER
SURFACE HIGH WILL LIKELY SHIFT SOUTHEAST SOMEWHERE ACROSS THE GREAT
LAKES ON OR AROUND THANKSGIVING. THE NORTHERLY FLOW THIS SETS UP
COULD PRODUCE SOME MORE LAKE EFFECT SNOW...AND IF THE FLOW TURNS
NORTHEAST AS THE GUIDANCE SUGGESTS BY THURSDAY...SOME OF THIS LAKE
EFFECT SNOW COULD AFFECT PORTIONS OF NORTHEASTERN ILLINOIS BEFORE IT
FADES. THIS IS STILL FAR OUT...BUT THE OVERALL SET UP FOR GOOD LAKE
EFFECT SNOW MAY NOT BE AS GOOD...ESPECIALLY BY THANKSGIVING...AS IT
APPEARS WARMER MID LEVEL TEMPERATURES MAY TRY TO QUICKLY OVERSPREAD
THE AREA IN RESPONSE TO RISING HEIGHTS ALOFT LATER NEXT WEEK. THIS
COULD ULTIMATELY LIMIT THE HEIGHT OF THE EQUILIBRIUM LEVELS FOR
PARCELS MODIFIED BY LAKE MICHIGAN. THIS WILL NEED TO BE WATCHED.
OTHERWISE IT JUST LOOKS UNSEASONABLY COLD AND DRY ACROSS MUCH OF THE
AREA THROUGH THANKSGIVING.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* NORTHERLY WINDS GUSTING TO AROUND 20 KT THROUGH MID-AFTERNOON.
* MVFR CIGS THROUGH MID-DAY.
* LIGHT RAIN ENDING AROUND 15Z...POSSIBLY BRIEFLY MIXING WITH -SN
BEFORE ENDING.
* NORTHWEST WINDS GUSTING TO 25-30 KT SATURDAY MORNING.
RATZER
//DISCUSSION...UPDATED 12Z...
AN UPPER LEVEL DISTURBANCE PASSING OVER THE AREA EARLY THIS
MORNING WILL CONTINUE LIGHT RAIN THROUGH DAYBREAK BEFORE ENDING
WITHIN AN HOUR OR TWO. WHILE THERE HAS BEEN A MIX WITH LIGHT SNOW
OR PELLETS ACROSS NORTHWEST IL AND EASTERN IA IN THE PAST SEVERAL
HOURS...THE SATURATION LAYER FOR SNOWFLAKES IS QUICKLY DRYING OUT
IN THE WAKE OF THIS DISTURBANCE. SO IF IT OCCURS IT SHOULD BE
LIGHT WITH NO ACCUMULATION. CLOUDS WILL GRADUALLY LIFT AND SCATTER
THROUGH EARLY TO MID AFTERNOON. NORTHERLY WINDS WILL CONTINUE WITH
GUSTS AT OR JUST ABOVE 20 KT THIS MORNING. A SECOND BUT MORE
POTENT COLD FRONT WILL SURGE SOUTHWARD ACROSS THE REGION LATE
TONIGHT INTO EARLY SATURDAY WHICH WILL BRING AN EVEN STRONGER
NORTHWEST WIND FOR SATURDAY MORNING WITH GUSTS IN THE 30 KT
BALLPARK. A SHORT PERIOD OF MVFR CIGS WITH FLURRIES IS POSSIBLE IN
THE IMMEDIATE POST FRONTAL PASSAGE AIRMASS.
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* HIGH CONFIDENCE IN WIND SPEEDS AND IN THE DIRECTION REMAINING
JUST SLIGHTLY WEST OF DUE NORTH.
* HIGH CONFIDENCE IN CIGS 1000 FT OR HIGHER IMPROVING ABOVE 1500
FT BY MID-MORNING.
* MEDIUM-HIGH CONFIDENCE IN PRECIP ENDING TIME AND LOW CONFIDENCE
IF A BRIEF MIX WITH SNOW WILL OCCUR.
* HIGH CONFIDENCE IN GUSTY NORTHWEST WINDS SATURDAY MORNING.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT-SUNDAY...VFR.
MONDAY...CHC OF -SN AND MVFR.
TUESDAY- WEDNESDAY...VFR.
THURSDAY...SLIGHT CHANCE OF LAKE EFFECT SNOW SHOWERS.
MTF
&&
.MARINE...
204 AM CST
AN ACTIVE LATE AUTUMN/EARLY WINTER PATTERN WILL PREVAIL ACROSS THE
LAKE THROUGH AT LEAST THE FIRST HALF OF NEXT WEEK. A COLD FRONT
WHICH PASSED LATE THURSDAY NIGHT HAS USHERED IN STIFF NORTH TO
NORTHWEST WINDS OVER THE LAKE WHICH WILL CONTINUE THROUGH MIDDAY
BEFORE EASING AND BACKING. WHILE THERE MAY BE A TEMPORARY BREAK IN
SMALL CRAFT ADVISORY CRITERIA TONIGHT...IT IS EXPECTED TO BE
BRIEF...SO HAVE CONTINUED THAT HEADLINE FOR THE IL AND IN
NEARSHORE.
ANOTHER COLD FRONT IS SET TO CROSS THE LAKE LATE TONIGHT WHICH WILL
BRING A PUNCH OF EVEN COLDER AIR. THIS WILL LEAD TO STEEPER LAPSE
RATES AND GREATER TRANSFER OF WIND MOMENTUM. IN RESPONSE...NORTHWEST
GALES ARE EXPECTED TO QUICKLY SPREAD DOWN THE LAKE PRIOR TO DAYBREAK
ON SATURDAY. GALES LOOK DEFINITE...MAYBE A FEW TO EVEN 40 KT. GALES
MAY EVEN BE EXPERIENCED IN NEAR SHORE AREAS OF INDIANA GIVEN THE
GREATER COMPONENT OF ONSHORE WIND DIRECTION AND REALIZED FETCH. AS
FOR FREEZING SPRAY SATURDAY...IT CONTINUES TO LOOK POSSIBLE BUT
MAINLY LIGHT DUE TO TOO WARM OF WATER TEMPERATURES.
A LARGE AND STRONG CANADIAN HIGH WILL MOVE TO THE SOUTH OF THE LAKE
ON SUNDAY AND THE PRESSURE GRADIENT ON ITS BACKSIDE WILL BE ENHANCED
BY LOW PRESSURE RACING ACROSS CANADA ON SUNDAY NIGHT INTO EARLY
MONDAY. THIS WILL AGAIN SET THE STAGE FOR POTENTIAL GALES...THIS
TIME FROM THE SOUTHWEST/WEST. HIGH PRESSURE LOOKS TO SLOWLY BUILD IN
THROUGH THE MIDWEEK TIME FRAME THEN...WITH INCREASING POTENTIAL FOR
LAKE EFFECT SNOWS ON THE CENTRAL...EASTERN...AND SOUTHERN PARTS OF
THE LAKE.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 AM SATURDAY TO 9 PM
SATURDAY.
SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 9 AM SATURDAY.
GALE WATCH...LMZ744-LMZ745...9 AM SATURDAY TO 9 PM SATURDAY.
SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 9 PM
SATURDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
547 AM CST Fri Nov 22 2013
.DISCUSSION...
ISSUED 220 AM CST Fri Nov 22 2013
The cold front has pushed through much of the forecast area early
this morning...and is about to clear the far southeast as of 2 am.
Some light post-frontal showers continue over the northwest half
of the area, while radar and surface obs showed some fairly
widespread light snow across much of central and eastern Iowa,
back where temperatures are mainly in the 20s. Have been seeing
some dense fog along and just behind the front, but this should
continue to lift as the front moves further east.
Main forecast concern involves the cold weekend weather, and
timing of the ending of the remaining precipitation today.
SHORT TERM...Today through Sunday:
Latest model trends continue to get the area largely dry by
midday. Colder air will make more of a surge later today, and most
areas should see steady or falling afternoon temperatures.
Arctic air mass over central Canada poised to surge southeast
through the Great Lakes this weekend. Brunt of the coldest air
still progged to stay to our north, but 850 mb temperatures drop
to around -14C here, so sub-freezing highs likely. Rather blustery
conditions expected Saturday ahead of strong Canadian high
pressure, but winds will subside on Sunday as the high drifts into
south central Illinois.
LONG TERM...Monday through Thanksgiving Day:
Large cutoff low, currently seen in water vapor imagery centered
near Los Angeles, should finally start to push eastward early next
week, as the deep trough in the northern stream finally pushes
to New England. Next shortwave in the northern stream is looking
to come through mainly dry Monday afternoon/night, as a storm
system develops along the Gulf. Deformation precipitation with
this system progged to reach about as far as the Ohio River as the
storm slowly moves into the Carolinas by midweek. This will
largely keep the Midwest dry from Tuesday through Thanksgiving,
except for some lake effect snow south of Lake Michigan. Second
Arctic surge at mid week is not quite as bitter as the upcoming
cold wave, but highs in the lower to mid 30s will be common for
the pre-Thanksgiving travel rush.
Geelhart
&&
.AVIATION...
ISSUED 545 AM CST Fri Nov 22 2013
Ifr conditions over region in the post frontal area over central
IL. IR satellite and moisture channel depicts minor wave moving
through central IL with debris from the AR pcpn. Very light pcpn
with this wave is gradually moving eastward over eastern CWA.
Expect cigs to only slowly raise til mid morning and then improve.
Drier air finally moves in during afternoon per the HRRR models
and then show increase cigs. The patchy vsbs in fog to improve
early this morning to vfr.
Goetsch
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
801 PM EST SAT NOV 23 2013
.SYNOPSIS...
ISSUED AT 724 PM EST SAT NOV 23 2013
A RIDGE OF HIGH PRESSURE ACCOMPANIED BY AN ARCTIC AIR MASS WILL
CONTINUE TO AFFECT THE REGION THROUGH SUNDAY. THIS COLD AIR OVER
THE WARMER LAKE MICHIGAN WATERS WILL RESULT IN CONTINUED LAKE
EFFECT SNOW SHOWERS ACROSS SOUTHWEST LOWER MICHIGAN AND NORTH
CENTRAL INDIANA THROUGH SUNDAY MORNING BEFORE DIMINISHING. SOME
MORE LIGHT SNOW IS POSSIBLE MONDAY AS AN UPPER LEVEL DISTURBANCE
TRACKS ACROSS THE GREAT LAKES.
&&
.UPDATE...
ISSUED AT 724 PM EST SAT NOV 23 2013
MULTI-BAND LAKE EFFECT WITH CELLULAR NATURE CONTINUES TO IMPACT
SOUTHWEST LOWER MICHIGAN AND NORTH CENTRAL INDIANA THIS EVENING.
FETCH CONSIDERATIONS AND EASTERN LAKE SHORE LAKE AGGREGATE
TROUGHING HAVE RESULTED IN PRIMARY AREA OF CONCERN FROM EXTREME
NORTHERN BERRIEN COUNTY EXTENDING SOUTHEASTWARD THROUGH SOUTHERN
CASS...ELKHART...AND NORTHEAST KOSCIUSKO COUNTIES. BOUNDARY LAYER
INSTABILITY AND STRENGTH OF LOW LEVEL FLOW HAS ALLOWED THESE BANDS
TO PENETRATE WELL INLAND WITH BRIEF PERIODS OF 1 TO 2 INCH PER
HOUR SNOWFALL RATES WITH MOST INTENSE BANDING. SUSTAINING THESE
TYPE OF SNOWFALL RATES HAS BEEN PROBLEMATIC HOWEVER DUE TO MORE
BROKEN...CELLULAR NATURE. OUTSIDE OF THIS MAIN BAND/STRONGEST LOW
LEVEL CONVERGENCE ZONE...GENERALLY ONLY A DUSTING TO A FEW TENTHS
OF AN INCH OF SNOW HAS BEEN REPORTED. ORGANIZATION HAS BEEN
SOMEWHAT LOOSE OVER PAST FEW HOURS POSSIBLY TIED SOMEWHAT INTO
PASSAGE OF UPPER LEVEL VORT MAX LATE AFTERNOON/EARLY EVENING. SOME
SYNOPTIC CONTRIBUTION EXPECTED OVERNIGHT HOWEVER...AS WEAK SHEARED
VORT MAX DOWNSTREAM OF APPROACHING RIDGE AXIS TRACKS INTO THE
WESTERN GREAT LAKES. THUS...WILL NEED TO WATCH FOR SOME BETTER
ORGANIZATION AS WE GET INTO THE LATE EVENING HOURS.
IT STILL APPEARS AS THOUGH MAIN LIMITING FACTOR FOG SIGNIFICANT
ACCUMULATIONS OVERNIGHT WILL CONTINUE TO BE VERY DRY NATURE TO THE
AIRMASS. NAM/RAP BUFFER SOUNDINGS SUGGEST PEAK LAKE INDUCED
INSTABILITY AROUND THE 06Z TIMEFRAME WITH FAVORABLE JUXTAPOSITION
OF STRONGEST LOW LEVEL VERTICAL MOTION WITH DGZ THROUGH THE
OVERNIGHT. HOWEVER...GRADUAL LOWERING OF INVERSION TOWARD MORNING
MAY TAKE STRONGEST VERTICAL MOTIONS JUST BELOW CORE OF DGZ BY 12Z.
GIVEN ABOVE FACTORS AND LIMITING FACTOR OF DRY LARGE SCALE AIR
MASS...STILL FEEL THAT PREVIOUS FORECAST IS IN GOOD SHAPE WITH
ADVISORY LEVEL ACCUMULATIONS. CONFIDENCE IN REACHING WARNING TYPE
ACCUMS GIVEN CELLULAR NATURE AND GRADUAL LOWERING INVERSION
HEIGHTS OVERNIGHT STILL QUITE LOW AND WILL NOT MAKE ANY CHANGES TO
GOING HEADLINES.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 400 PM EST SAT NOV 23 2013
ARCTIC AIRMASS ASSOCIATED WITH 1050MB SURFACE HIGH IS CURRENTLY
ENGULFING THE REGION...LEADING TO FALLING TEMPS AND A DECENT LAKE
RESPONSE. 850MB TEMPS CONTINUE TO FALL INTO THE UPPER TEENS BELOW
ZERO AND 700MB DELTA-T`S ARE AT OR ABOVE 30C. CERTAINLY PLENTY OF
LAKE INDUCED INSTABILITY BUT DEGREE OF UPSTREAM DRY AIR AND LOW
LEVEL FLOW TRAJECTORIES REMAIN A LIMITING FACTOR. AS PREVIOUSLY
MENTIONED...SURFACE DEWPOINTS OVER WISCONSIN ARE HOVERING AT OR
BELOW ZERO. 330 DEGREE SURFACE WINDS GIVE A DECENT FETCH ALONG LAKE
MICHIGAN BUT MOISTURE AND SENSIBLE/LATENT HEAT FLUX CAN ONLY DO SO
MUCH...ESPECIALLY GIVEN STRONG GRADIENT AND MARGINAL UPSTREAM
PRECONDITIONING FROM WESTERN LAKE SUPERIOR. THIS IS BORNE OUT BY
RELATIVELY DRY NEAR SURFACE PROFILES ON FORECAST SOUNDINGS AND
CEILINGS GENERALLY ABOVE 3 KFT DURING THE DAY TODAY. DRY AIR ALOFT
IS ALSO PREVENTING CONVECTIVE DEPTHS FROM GETTING MUCH ABOVE 7
KFT...PER NAM AND RAP FORECAST SOUNDINGS. APPEARS TO BE SOME
SEMBLANCE OF FRICTIONAL CONVERGENCE OR THERMALLY-INDUCED PRESSURE
TROUGHING ALONG THE EASTERN SHORE OF LAKE MICHIGAN BUT STRONG
NORTHWEST GRADIENT IS DISRUPTING THE FORMATION OF A SINGLE DOMINANT
BAND AND HEAVIER SNOW SHOWERS HAVE BEEN FAIRLY SPORADIC AND
DISORGANIZED THROUGHOUT THE DAY. 12Z HI-RES GUIDANCE SUGGESTS BANDS
MAY BECOME A LITTLE BETTER ORGANIZED OVERNIGHT BUT THE
AFOREMENTIONED LIMITING FACTORS WILL REMAIN LARGELY IN PLACE THROUGH
THE MORNING WITH A STIFF NORTHWEST WIND...PERSISTENT SYNOPTIC-SCALE
DRY AIR ADVECTION...AND A WELL MIXED BOUNDARY LAYER. STRONG
INSTABILITY...LONG DURATION...AND NEARLY IDEAL DGZ PLACEMENT WILL
CONTINUE TO AT LEAST PARTIALLY OFFSET THOSE NEGATIVE FACTORS THOUGH
AND WILL CONTINUE TO SEE SPURTS OF HEAVIER SNOW SHOWERS THROUGH
TOMORROW MORNING THAT COULD EVENTUALLY ADD UP TO 3-5 INCHES IN THE
ADVISORY AREA. STILL DONT EXPECT WARNING CRITERIA SNOWFALL. THE ONLY
POSSIBLE EXCEPTION MAY BE IN CASS COUNTY MI WHERE 5-8 INCHES MAY BE
POSSIBLE IF A MORE ORGANIZED/FOCUSED BAND DEVELOPS BUT CONFIDENCE IN
THIS OCCURRING IS TOO LOW TO WARRANT AN UPGRADE AT THIS POINT.
BACKING LOW LEVEL WINDS AND PERSISTENT SUBSIDENCE/DRY AIR ADVECTION
WILL BRING AN END TO LAKE AFFECT SNOW SHOWERS AROUND MIDDAY TOMORROW.
OTHER MAIN STORY DURING THIS SHORT TERM PERIOD WILL BE THE VERY COLD
TEMPERATURES. STRONG GRADIENT AND LAKE INDUCED CLOUD COVER WILL
PREVENT ANY DECOUPLING OR RADIATIVE COOLING OVERNIGHT FOR MOST OF
OUR CWA BUT VERY COLD THERMAL PROFILES ADVECTING INTO THE AREA WILL
STILL SUPPORT LOWS GENERALLY IN THE MID TEENS. COMBINED WITH THE
WIND...IT WILL FEEL LIKE THE LOW SINGLE DIGITS IN SOME AREAS. HIGHS
TOMORROW WILL STRUGGLE TO GET OUT OF THE MID 20S GIVEN 925MB TEMPS
STILL AROUND -11C. MODELS CONTINUE TO STRUGGLE WITH THE MAGNITUDE OF
THIS COLD AIRMASS AND HAVE CONTINUED TO LEAN ON THE COOLER SIDE OF
GUIDANCE.
&&
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 400 PM EST SAT NOV 23 2013
PREFERENCE THIS AFTN LIES W/SHARPER H5 EVOLUTION ALOFT MID PD IN
RESPONSE TO EWD EJECTION OF STG SRN STREAM SW UNDERNEATH AMPLIFYING
NRN STREAM ACRS THE WRN LAKES WHICH PROVIDES A PATHWAY FOR SOME XPCD
PHASING ALOFT. AS SUCH AND IN TANDEM W/GEM/NAM/EC TRENDS...BUMPED
POPS CONSIDERABLY WED-THU FOR WHAT SHLD BE A SIG LK EFFECT SNOW
EVENT AS YET ANOTHER SURGE OF COLD CANADIAN AIR FUNNELS SWD ACRS THE
LAKES.
STEEP NW FLW ALOFT CONTS THROUGH THE END OF THE PD W/PROMISE OF
CONTD WELL BLO NORMAL TEMPS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 724 PM EST SAT NOV 23 2013
ARCTIC AIR MASS AND NORTHWEST LOW LEVEL FLOW TRAJECTORIES WILL
CONTINUE TO SUPPORT LAKE EFFECT SHOWERS AT THE TERMINALS THROUGH
EARLY AM SUNDAY. ORGANIZATION OF LAKE EFFECT BANDING HAS BEEN
SOMEWHAT LOOSE AT THIS TIME WITH POTENTIAL FOR HEAVIEST
ACCUMULATIONS REMAINING JUST EAST/NORTHEAST OF KSBN. EMBEDDED
CELLULAR NATURE TO THE BANDING SHOULD SUPPORT SOME SHORT LIVED IFR
VSBY RESTRICTIONS HOWEVER AT KSBN. GIVEN STRENGTH OF FLOW...EVEN
KFWA SHOULD CONTINUE TO EXPERIENCE SCT SNOW SHOWERS...ALTHOUGH
CONFIDENCE IN ANY IFR VSBY RESTRICTIONS SOMEWHAT LOWER. OUTSIDE OF
ANY ENHANCED LAKE EFFECT SNOW SHOWERS...GENERALLY MVFR CIGS
EXPECTED AT KSBN. WINDS TO GRADUALLY DIMINISH OVERNIGHT...AND WILL
SETTLE WESTERLY AT 10 TO 15 KNOTS FOR SUNDAY. BACKING LOW LEVEL
WINDS SUNDAY MORNING WILL TAKE LAKE EFFECT SNOW SHOWER THREAT
NORTH OF KSBN BY MID MORNING.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST SUNDAY FOR INZ004>006.
MI...LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST SUNDAY FOR MIZ077>079.
OH...NONE.
LM...GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ043-046.
&&
$$
UPDATE...MARSILI
SYNOPSIS...MARSILI
SHORT TERM...AGD
LONG TERM...T
AVIATION...MARSILI
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AREA FORECAST DISCUSSION
NWS DODGE CITY KS
535 PM CST Sat Nov 23 2013
...Updated aviation discussion...
.SYNOPSIS...
ISSUED AT 1109 AM CST SAT NOV 23 2013
At 12z Saturday a -25c 500mb low was located over southern
California. A 300mb +100kt jet streak extended from the based of
this upper low northeast into the four corners region. A 700mb to
500mb deformation zone was located from Wyoming, across Colorado,
into Oklahoma and a 700mb baroclinic zone extended from southern
Colorado into northern Oklahoma. Along and south of this
baroclinic zone was also where the better 850mb to 500mb moisture
appears to be located based on upper air analysis. A surface to
850mb ridge axis extended from northeast New Mexico into southern
Nebraska. An area of high pressure at the surface at 12z was
located over the eastern Dakotas. The Dodge City sounding this
morning indicated a of drier air was located in the 900mb to 750mb
layer, however the Amarillo sounding indicated a deep layer of
moisture extending from the surface to the 700mb layer.
&&
.SHORT TERM...(This evening through Sunday)
ISSUED AT 218 PM CST SAT NOV 23 2013
Models this morning were all in decent agreement with the
southern California upper low slowly moving east across the
southwest United States over the next 24 hours. Ahead of this
upper trough, isentropic lift and moisture on the I290 and I295
surfaces will improve across southwest Kansas. As this moisture
and lift improves the clouds will thicken and lower with even some
light snow becoming possible across far southwest Kansas after 03z
based on the NAM. The latest HRRR was even a bit more aggressive
with the precipitation spreading into southwest Kansas after 00z
Sunday, and currently given the precipitation that was already
occurring near Amarillo as of 19z will begin to trend toward this
slightly quicker solution. This area of light snow will then
spread north and east through the overnight period but the better
moisture return and isentropic lift still appears to be confined
near and south of the Oklahoma border overnight. As a result not
expected much in the way of accumulation until the 300mb jet,
which was located over Arizona at 12z, begins to approach
southwest Kansas after 06z. Possible exception to this will be
extreme southwest Kansas near Elkhart.
Steady light snow will spread across southwest Kansas after 06z
Sunday as synoptic scale lift improves. Given that the moisture
and low level isentropic lift will already be in place am
currently leaning towards the NAM in snowfall amounts from roughly
06z to 18z Sunday. As a result snow amounts ranging from one to
around two inches still appear reasonable south of a Ulysses to
Dodge City to Pratt line. The higher 2 inch amounts will be mainly
confined near the Oklahoma border on Sunday. Given snow amounts of
around 2 inches being possible near the Oklahoma border was
considering a winter weather advisory, however at this time given
that this is expected to be only a marginal event over a small
area have decided to hold off with any type of headlines. Snow
accumulations of less than one inch is likely further north given
the late timing of the isentropic lift and depth of dry air
forecast in the lower levels.
.LONG TERM...(Sunday night through Saturday)
ISSUED AT 150 PM CST SAT NOV 23 2013
Moderation of temperatures is expected in the extended period.
Values will start below normal Monday and end up around normal by
next Saturday. No precipitation is expected during the period as
moisture will remain well southeast of the area. A series of weak
front will move across the region next week with the main impact in
the form of wind shifts.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
ISSUED AT 535 PM CST SAT NOV 23 2013
This period will start out with VFR cigs at the taf sites.
Look for ceilings and visibilities to lower into the MVFR/IFR
categories at Garden City and Dodge City later tonight into Sunday
morning. The snow should be tapering off after 14-16z with
visibilities improving to VFR with flurries into the afternoon
hours. Hays could see MVFR ceilings and visibilities for a short
time around late Sunday morning into early Sunday afternoon but
should otherwise remain VFR.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 18 29 23 37 / 20 30 10 10
GCK 18 30 21 38 / 20 30 10 10
EHA 22 29 23 35 / 80 60 10 10
LBL 22 30 22 34 / 80 70 10 10
HYS 13 31 20 39 / 0 20 10 10
P28 17 28 24 36 / 30 50 20 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Burgert
SHORT TERM...Burgert
LONG TERM...Sugden
AVIATION...Gerard
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1135 PM CST Thu Nov 21 2013
.UPDATE...
Issued at 955 PM CST THU NOV 21 2013
The low-level CAA will continue to deepen the drier cold airmass
over the CWA through the morning hours. The patchy freezing
drizzle will end after midnight. The NAM model continues to show a
band of mid-level frontogenetical forcing moving east across
eastern KS tonight. This may cause snow flurries or scattered snow
and sleet showers through the early morning hours. Meanwhile, the
low-levels of the atmosphere will continue to dry through the
night due to the stronger low-level CAA. Any additional patchy
freezing drizzle along with wet road surfaces from the earlier
freezing rain will cause roadways to be very slick through
sunrise as overnight lows drop into the upper teens to mid 20s.
Therefore, the winter weather advisory will continue across
northeast and east central KS through 12Z. The next shift may
expire the winter weather advisory before 400 AM if road
conditions improve.
The 00z run of the NAM shows the next band of stronger
frontogenetical forcing remaining south of the CWA across southern
KS and northern OK, where steady light snow may develop. Therefore, I have
expired the winter weather advisory for our southeast counties for
Friday morning between 600 AM and noon.
&&
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Friday)
Issued at 256 PM CST THU NOV 21 2013
.Synopsis...
Water vapor imagery shows a shortwave trough over the northern
plains propagating east towards the great lakes, while energy
begins to cut off over central CA. At the surface, a strong cold
front has pushed through the entire forecast area with
temperatures continuing to fall in response to strong cold air
advection.
.Short Term... (Tonight)
For tonight the forcing for continued precipitation looks to be
mainly driven by mid level frontogenesis. The NAM and RAP progs
show weakening isentropic upglide early in the evening as the 850
front continues to push south. Then by the late evening and
overnight mid level drying near the better mid level
frontogenetical forcing suggests that precip could come to an end
since there is no lift within the low level cloud from isentropic
features for light freezing drizzle. With this in mind have
trended POPs down for most areas overnight. The latest
HRRR/RAP13/NAM12 continue to show this band of precip currently
from Minneapolis to Hiawatha, associated with some mid level
frontogenesis, to lift northeast into northwest MO. Therefore have
some likely pops for the early evening across far northeast KS.
Otherwise the forecast will only have some chance pops through the
rest of tonight. Did not feel confident enough to lower pops any
further since there will be some mid level frontogenesis through
the night. Also will not make any major changes to the advisory
other than to end it earlier in the day Friday. It is one of those
situations that with the advisory already out it doesn`t make
sense to cancel it early since there remains the potential for
some light frozen precip with reports of slick roads coming in.
Since forcing is weak and moisture will continue to lessen through
the night, additional precipitation is anticipated to be on the
light side with accumulations generally around a tenth of an inch in
water equivalent. The mid level drying will also make it difficult
for snow to occur since the dendritic growth zone is not expected to
be saturated. Because of this there shouldn`t be any ice crystals
for snow. So think freezing rain and sleet will be the primary
precip type through the night if precip does fall. Continued cold
air advection should cause temperatures to fall into the teens and
mid 20s for the forecast area by sunrise Friday.
.LONG TERM...(Friday Night through Thursday)
Issued at 256 PM CST THU NOV 21 2013
Friday...Becomes a race with the incoming drier air as to how much
precipitation can fall on Friday as high pressure continues to surge
into the southern plains through the day. Back to the west an upper
low advances into Baja, lifting a lobe of moisture into southern
Kansas in the mid levels. Frontogenesis gets some further
enhancement from northern trof dropping energy into the area mid to
late day. Isentropic charts indicate downglide in the lower levels,
with 700mb chart showing some broad convergence in the wind field
through the noon hour. With lack of strong lift and incoming drier
air have pulled back on precip chances and amounts but not ready to
remove entirely for the southern counties just yet. Enough
consensus in incoming dry air from north to end the advisory earlier
for generally the I70 counties, but will hang onto it through noon
for those south of I70. Temperature profiles are finally cold enough
for all snow along the northern edge but hold onto a weak warm nose
across the SE and will keep a S/IP mix for these areas. Went colder
on both highs and lows given current reflection in observations with
highs upper 20s to near freezing and dropping overnight into the
upper teens.
Saturday and Sunday... Continue to go on the cool side of guidance
on Saturday with high pressure still on the move to the south. Have
highs near freezing and lows in the lower to middle teens. Incoming
clouds from the southwest on Sunday plus a return to southerly
surface low on the wrn side of the high should bring highs back into
the middle 30s on Sunday.
Monday: An upper level trough forming out of the Four Corners region
will propagate to the east. The 12Z ECMWF/GFS are in reasonable
agreement pertaining to the location of the trough. A jet streak of
up to 100kt winds associated with this trough should eject
additional moisture into Oklahoma and Kansas. Southerly winds in
this region should help support moisture transfer over eastern
Kansas. This additional moisture, along with freezing temperatures,
could support light snow over eastern Kansas.
By Tuesday, the trough should pivot to the south due to a ridging
stream wave over the western CONUS. The trough should stay further
south into Texas and Oklahoma. Winds shift from southerly to
northerly as the trough moves south. The ridging pattern over the
western CONUS will translate towards the east by Wednesday, bringing
quiet weather to the region. Lows will be in the 20s overnight and
highs will be in the upper 30s/lower 40s for the rest of the week.
&&
.AVIATION...(For the 06Z TAFs through 06Z Friday Night)
Issued at 1128 PM CST THU NOV 21 2013
Stratus cloud cover with MVFR ceilings will continue through the
night and morning hours of Friday. There may be some patchy light
freezing drizzle at the KFOE and KTOP terminals through 8Z FRI.
May see occasional flurries through the night. The lower stratus
should scatter out by early afternoon at the TAF sites. North
winds of 12 to 15 KTS with higher gusts this morning will diminish
by mid and late afternoon.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY until 6 AM CST Friday FOR KSZ010>012-
022>024-026-036>040-054>056-058-059.
&&
$$
UPDATE...Gargan
SHORT TERM...67/Wolters
LONG TERM...67/JTS
AVIATION...Gargan
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1012 PM CST Thu Nov 21 2013
.UPDATE...
Issued at 955 PM CST THU NOV 21 2013
The low-level CAA will continue to deepen the drier cold airmass
over the CWA through the morning hours. The patchy freezing
drizzle will end after midnight. The NAM model continues to show a
band of mid-level frontogenetical forcing moving east across
eastern KS tonight. This may cause snow flurries or scattered snow
and sleet showers through the early morning hours. Meanwhile, the
low-levels of the atmosphere will continue to dry through the
night due to the stronger low-level CAA. Any additional patchy
freezing drizzle along with wet road surfaces from the earlier
freezing rain will cause roadways to be very slick through
sunrise as overnight lows drop into the upper teens to mid 20s.
Therefore, the winter weather advisory will continue across
northeast and east central KS through 12Z. The next shift may
expire the winter weather advisory before 400 AM if road
conditions improve.
The 00z run of the NAM shows the next band of stronger
frontogenetical forcing remaining south of the CWA across southern
KS and northern OK, where steady light snow may develop. Therefore, I have
expired the winter weather advisory for our southeast counties for
Friday morning between 600 AM and noon.
Gargan
&&
.SHORT TERM...(This Evening through Friday)
Issued at 256 PM CST THU NOV 21 2013
.Synopsis...
Water vapor imagery shows a shortwave trough over the northern
plains propagating east towards the great lakes, while energy
begins to cut off over central CA. At the surface, a strong cold
front has pushed through the entire forecast area with
temperatures continuing to fall in response to strong cold air
advection.
.Short Term... (Tonight)
For tonight the forcing for continued precipitation looks to be
mainly driven by mid level frontogenesis. The NAM and RAP progs
show weakening isentropic upglide early in the evening as the 850
front continues to push south. Then by the late evening and
overnight mid level drying near the better mid level
frontogenetical forcing suggests that precip could come to an end
since there is no lift within the low level cloud from isentropic
features for light freezing drizzle. With this in mind have
trended POPs down for most areas overnight. The latest
HRRR/RAP13/NAM12 continue to show this band of precip currently
from Minneapolis to Hiawatha, associated with some mid level
frontogenesis, to lift northeast into northwest MO. Therefore have
some likely pops for the early evening across far northeast KS.
Otherwise the forecast will only have some chance pops through the
rest of tonight. Did not feel confident enough to lower pops any
further since there will be some mid level frontogenesis through
the night. Also will not make any major changes to the advisory
other than to end it earlier in the day Friday. It is one of those
situations that with the advisory already out it doesn`t make
sense to cancel it early since there remains the potential for
some light frozen precip with reports of slick roads coming in.
Since forcing is weak and moisture will continue to lessen through
the night, additional precipitation is anticipated to be on the
light side with accumulations generally around a tenth of an inch in
water equivalent. The mid level drying will also make it difficult
for snow to occur since the dendritic growth zone is not expected to
be saturated. Because of this there shouldn`t be any ice crystals
for snow. So think freezing rain and sleet will be the primary
precip type through the night if precip does fall. Continued cold
air advection should cause temperatures to fall into the teens and
mid 20s for the forecast area by sunrise Friday.
.LONG TERM...(Friday Night through Thursday)
Issued at 256 PM CST THU NOV 21 2013
Friday...Becomes a race with the incoming drier air as to how much
precipitation can fall on Friday as high pressure continues to surge
into the southern plains through the day. Back to the west an upper
low advances into Baja, lifting a lobe of moisture into southern
Kansas in the mid levels. Frontogenesis gets some further
enhancement from northern trof dropping energy into the area mid to
late day. Isentropic charts indicate downglide in the lower levels,
with 700mb chart showing some broad convergence in the wind field
through the noon hour. With lack of strong lift and incoming drier
air have pulled back on precip chances and amounts but not ready to
remove entirely for the southern counties just yet. Enough
consensus in incoming dry air from north to end the advisory earlier
for generally the I70 counties, but will hang onto it through noon
for those south of I70. Temperature profiles are finally cold enough
for all snow along the northern edge but hold onto a weak warm nose
across the SE and will keep a S/IP mix for these areas. Went colder
on both highs and lows given current reflection in observations with
highs upper 20s to near freezing and dropping overnight into the
upper teens.
Saturday and Sunday... Continue to go on the cool side of guidance
on Saturday with high pressure still on the move to the south. Have
highs near freezing and lows in the lower to middle teens. Incoming
clouds from the southwest on Sunday plus a return to southerly
surface low on the wrn side of the high should bring highs back into
the middle 30s on Sunday.
Monday: An upper level trough forming out of the Four Corners region
will propagate to the east. The 12Z ECMWF/GFS are in reasonable
agreement pertaining to the location of the trough. A jet streak of
up to 100kt winds associated with this trough should eject
additional moisture into Oklahoma and Kansas. Southerly winds in
this region should help support moisture transfer over eastern
Kansas. This additional moisture, along with freezing temperatures,
could support light snow over eastern Kansas.
By Tuesday, the trough should pivot to the south due to a ridging
stream wave over the western CONUS. The trough should stay further
south into Texas and Oklahoma. Winds shift from southerly to
northerly as the trough moves south. The ridging pattern over the
western CONUS will translate towards the east by Wednesday, bringing
quiet weather to the region. Lows will be in the 20s overnight and
highs will be in the upper 30s/lower 40s for the rest of the week.
&&
.AVIATION...(For the 00Z TAFs through 00Z Friday Evening)
Issued at 527 PM CST THU NOV 21 2013
Stronger forcing now coming through the Taf sites with an IFR mixture
of freezing drizzle...sleet and snow. Expect this precip to
gradually diminish through 04z but with mvfr cigs in its wake. As
drier air aloft moves in...still some potential for light freezing
drizzle but confidence remains too low to insert into Tafs at
this point. North winds will gust to 25 kts overnight...but
steadily decrease through the day Friday. MVFR cigs should scatter
to vfr in the 19-21Z time frame.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY until 6 AM CST Friday FOR KSZ010>012-
022>024-026-036>040-054>056-058-059.
&&
$$
UPDATE...Gargan
SHORT TERM...67/Wolters
LONG TERM...67/JTS
AVIATION...63
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
930 PM EST SAT NOV 23 2013
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION TONIGHT WITH A STRONG NORTHWEST
FLOW SETTING UP BEHIND IT. HIGH PRESSURE WILL BUILD SOUTH OF NEW
ENGLAND SUNDAY THROUGH MONDAY. A COLD FRONT WILL SLOWLY APPROACH
FROM THE WEST MONDAY NIGHT AND TUESDAY AND WILL CROSS THE REGION
TUESDAY NIGHT. LOW PRESSURE WILL MOVE UP THE EAST COAST ON
WEDNESDAY. HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE WEST
THURSDAY THROUGH FRIDAY. HIGH PRESSURE WILL CREST OVER THE REGION
ON FRIDAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
UPDATE...HAVE UPDATED POP ONCE AGAIN TO TRACK THE LATEST BATCH OF
SN SQUALLS CROSSING THE WHITE MTNS ATTM. THE 24/00Z HRRR ACTUALLY
HAS A VERY GOOD HANDLE ON THE CURRENT SPEED AND FAIR ESTIMATE ON
LOCATION OF THE SQUALL. SO HAVE BLENDED THE PREVIOUS FORECAST WITH
THIS LATEST GUIDANCE TO BRING THE OFFICIAL FORECAST IN THAT
DIRECTION FOR THE NEXT SEVERAL HOURS. WILL CONTINUE HEAVY SNFL
WORDING WITH THIS PCPN...AS EVEN THOUGH THE DURATION WILL BE SHORT
LIVED...THE INTENSITY WILL BE ENOUGH TO CAUSE TROUBLE.
PREVIOUS DISCUSSION...ARCTIC COLD FNT MAKING QUICK PROGRESS
TOWARDS THE CWFA ATTM. SHSN AND SQUALLS WILL BECOME MORE NUMEROUS
AS IT APPROACHES THIS EVENING. STRONG CAA IS DESTABILIZING THE
LLVLS...ALLOWING SHSN TO BECOME QUITE INTENSE AT TIMES. LOOKING AT
UPSTREAM OBS AND WEBCAMS...VSBYS WILL DROP TO 1/4SM OR LESS AT
TIMES. HAVE ADDED HEAVY SN WORDING TO SRN NH AND ADJACENT SWRN ME
FOR THE NEXT SEVERAL HOURS AS SQUALLS TRACK OVER THESE AREAS.
ADDITIONALLY...ABOVE FREEZING TEMPS TODAY WILL MEAN ROAD TEMPS
WILL BE WARM ENOUGH TO MELT SNFL INITIALLY. HOWEVER...RAPIDLY
FALLING TEMPS WILL MEAN THIS WILL REFREEZE...CREATING VERY ICY
ROADWAYS. SEEING AS THESE SHSN WILL BE CROSSING INTERSTATES
89...93...AND 95 THIS IS A CONCERN. USED A BLEND OF THE LATEST RAP
AND HRRR TO TREND POP OVER THE NEXT FEW HOURS. OTHERWISE FORECAST
LOOKS ON TRACK AS BITTER COLD HEADS TOWARDS THE REGION.
&&
.SHORT TERM /SUNDAY NIGHT/...
FOR SUNDAY WE HAVE ISSUED A WIND ADVISORY. LOOKING AT BUFKIT DATA
SHOWS WINDS TO 40 TO 50 KTS DOWN TO 2K FEET WITH STEEP LAPSE
RATES. THE STRONGEST WINDS ARE LIKELY TO BE IN THE 18Z TO 03Z TIME
FRAME. WINDS GUSTS TO 45 TO 50 MPH ARE CERTAINLY POSSIBLE. EXPECT
THERE WILL BE POWER OUTAGES AS THE DAY GOES ON. TEMPERATURES WILL
RISE ABOUT 5 TO 10 DEGREES TOMORROW WHICH WILL PUT HIGH TEMPS IN
THE 20S MOST EVERYWHERE WITH SOME UPPER TEENS IN THE MOUNTAINS.
THIS IS A GOOD 20 DEGREES BELOW NORMAL. SNOW SHOWERS WILL BE
LIKELY IN THE MOUNTAINS WITH 1 TO 3 INCHES POSSIBLE. FOR SUNDAY
NIGHT WINDS WILL ABATE SOMEWHAT AFTER MIDNIGHT BUT TEMPS WILL
PLUNGE. EXPECT AROUND ZERO IN THE MOUNTAINS AND NEAR 10 AT THE
COAST. RECORD LOW FOR PORTLAND MONDAY IS 9 DEGREES. WILL BE CLOSE
TO THIS.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
RIDGE OF HIGH PRESSURE WILL CREST OVER THE REGION MONDAY BEFORE
SHIFTING OFFSHORE. EXPECT A SUNNY START TO THE DAY BEFORE HIGH
CLOUDS SPILL IN FROM THE WEST IN THE AFTERNOON. WILL BE ANOTHER COLD
ONE WITH HIGHS ONLY REACHING THE UPPER TEENS TO LOWER 20S NORTH AND
MID 20S TO NEAR 30 SOUTH.
AREA OF WEAK OVER-RUNNING AHEAD LOW PRESSURE MOVING THROUGH SOUTHERN
CANADA WILL PUSH IN FROM THE WEST MONDAY NIGHT BRINGING SOME LIGHT
SNOW TO THE REGION. BEST CHANCES OF PRECIP WILL BE IN NORTHERN ZONES
WHERE AN INCH OR TWO OF ACCUMULATION WILL BE POSSIBLE. ELSEWHERE
JUST LOOKING FOR A LIGHT DUSTING. LOOKING FOR LOWS IN THE MID TEENS
TO LOWER 20S.
CLOUDS AND LINGERING FLURRIES WILL GIVE WAY TO PARTLY SUNNY SKIES ON
TUESDAY. COLD FRONT APPROACHING FROM THE WEST MAY BRING SNOW SHOWERS
TO THE MOUNTAINS BY LATE IN THE DAY. SHOULD SEE A MUCH WARMER DAY
WITH TEMPS RANGING THROUGH THE 30S.
COLD FRONT WILL SWING THROUGH THE REGION TUESDAY NIGHT BRINGING A
CHANCE OF SNOW SHOWERS IN THE NORTH AND VARIABLE CLOUDS ACROSS
SOUTHERN AREAS. OVERNIGHT LOWS WILL RANGE THROUGH THE 20S.
MODELS STILL FAR APART ON WEDNESDAY WITH THE ECMWF BRINGING LOW
PRESSURE UP THE EAST COAST AND GFS TAKING THE SAME SYSTEM WELL
OFFSHORE. AT THIS POINT SUPER BLEND GIVING LIKELY POPS WITH A MIX OF
RAIN AND SNOW IN THE SOUTH AND SNOW IN THE FOOTHILLS AND NORTH. SO
POTENTIAL IS STILL THERE FOR SIGNIFICANT SNOW IN THE NORTH AND A
MESSY MIX IN THE SOUTH. HIGH TEMPS WILL RANGE THOUGH THE 30S TO
NEAR 40.
HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE WEST THURSDAY
THROUGH FRIDAY. EXPECT TEMPS ONCE AGAIN BELOW NORMAL THURSDAY AS
COLD CANADIAN AIR FLOODS IN ON A STRONG NORTHERLY WINDS. WILL SEE
TEMPS MODERATE SOMEWHAT ON FRIDAY AS HIGH PRESSURE CRESTS OVER THE
REGION.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...EXPECT MOSTLY VFR. BRIEF MVFR/IFR PSBL LATE TONIGHT
IN SNOW SHOWERS. HIE WILL SEE MOSTLY MVFR.
LONG TERM...VFR MONDAY THROUGH TUESDAY. IFR/LIFR CEILINGS AND VSBY
DEVELOPING ON WEDNESDAY. VFR THURSDAY.
&&
.MARINE...
SHORT TERM...GALE WARNING HAS BEEN ISSUED.
LONG TERM...GALES POSSIBLE ON WEDNESDAY.
&&
.CLIMATE...
SIGNIFICANT OUTBREAK OF EARLY SEASON COLD AIR WILL CHALLENGE SOME
LOCAL RECORDS OVER THE NEXT COUPLE OF DAYS. AT KPWM THE RECORD
COLD MAXIMUM TEMP FOR 11/24 IS 28 SET IN 1989. THE TEMP AROUND
MIDNIGHT TONIGHT WILL LIKELY BE THE WARMEST KPWM GETS ALL
DAY...AND WILL BE VERY CLOSE TO 28 DEG. ON 11/25 KPWM HAS A RECORD
COLD MAXIMUM TEMP OF 29 SET IN 1993. THE CURRENT FORECAST IS FOR A
HIGH TEMP AROUND 30. FOR LOW TEMP ON 11/25...KPWM SET A RECORD IN
2000 OF 9 DEG. THE CURRENT FORECAST IS FOR 11/25 IS A LOW TEMP
AROUND 10 DEG.
A LITTLE COOLER BUT SIMILARLY FOR KCON...THE RECORD COLD MAXIMUM
TEMP FOR 11/24 IS 24 SET IN 1921. WHILE IN 1938 THE RECORD COLD
MAXIMUM TEMP FOR 11/25 WAS SET AT 21. THE RECORD LOW TEMP FOR
11/25 IS 5 DEG SET IN 1956 AND 2000.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WIND ADVISORY FROM 7 AM SUNDAY TO 1 AM EST MONDAY FOR
MEZ007>009-012>014-018>028.
NH...WIND ADVISORY FROM 7 AM SUNDAY TO 1 AM EST MONDAY FOR
NHZ001>010-013-014.
MARINE...GALE WARNING FROM 7 AM SUNDAY TO 7 AM EST MONDAY FOR
ANZ150>154.
&&
$$
NEAR TERM...LEGRO
AREA FORECAST DISCUSSION
NWS GRAY ME
743 PM EST SAT NOV 23 2013
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION TONIGHT WITH A STRONG NORTHWEST
FLOW SETTING UP BEHIND IT. HIGH PRESSURE WILL BUILD SOUTH OF NEW
ENGLAND SUNDAY THROUGH MONDAY. A COLD FRONT WILL SLOWLY APPROACH
FROM THE WEST MONDAY NIGHT AND TUESDAY AND WILL CROSS THE REGION
TUESDAY NIGHT. LOW PRESSURE WILL MOVE UP THE EAST COAST ON
WEDNESDAY. HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE WEST
THURSDAY THROUGH FRIDAY. HIGH PRESSURE WILL CREST OVER THE REGION
ON FRIDAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
UPDATE...NO MAJOR CHANGES WITH THIS FORECAST UPDATE. MOSTLY
TWEAKED POP BASED ON LATEST RADAR TRENDS AND BLENDED WITH THE RAP
AND HRRR OUT THRU THE NEXT 6 HOURS. ARCTIC FNT CONTINUES TO MAKE
PROGRESS TOWARDS THE CWFA...WITH SHARP TRANSITION TO PRES RISES
SOON ACROSS THE WRN ZONES. THIS WILL BRING THE WINDS BACK UP...AS
CAA WILL CONTINUE RIGHT THRU TOMORROW. ONE BAND OF SN SQUALLS AHEAD
OF THIS FNT IS CROSSING SRN NH ATTM...WITH A SECOND AREA ACROSS
NRN VT SET TO DROP THRU THE AREA IN THE NEXT COUPLE OF HOURS.
PREVIOUS DISCUSSION...ARCTIC COLD FNT MAKING QUICK PROGRESS
TOWARDS THE CWFA ATTM. SHSN AND SQUALLS WILL BECOME MORE NUMEROUS
AS IT APPROACHES THIS EVENING. STRONG CAA IS DESTABILIZING THE
LLVLS...ALLOWING SHSN TO BECOME QUITE INTENSE AT TIMES. LOOKING AT
UPSTREAM OBS AND WEBCAMS...VSBYS WILL DROP TO 1/4SM OR LESS AT
TIMES. HAVE ADDED HEAVY SN WORDING TO SRN NH AND ADJACENT SWRN ME
FOR THE NEXT SEVERAL HOURS AS SQUALLS TRACK OVER THESE AREAS.
ADDITIONALLY...ABOVE FREEZING TEMPS TODAY WILL MEAN ROAD TEMPS
WILL BE WARM ENOUGH TO MELT SNFL INITIALLY. HOWEVER...RAPIDLY
FALLING TEMPS WILL MEAN THIS WILL REFREEZE...CREATING VERY ICY
ROADWAYS. SEEING AS THESE SHSN WILL BE CROSSING INTERSTATES
89...93...AND 95 THIS IS A CONCERN. USED A BLEND OF THE LATEST RAP
AND HRRR TO TREND POP OVER THE NEXT FEW HOURS. OTHERWISE FORECAST
LOOKS ON TRACK AS BITTER COLD HEADS TOWARDS THE REGION.
&&
.SHORT TERM /SUNDAY NIGHT/...
FOR SUNDAY WE HAVE ISSUED A WIND ADVISORY. LOOKING AT BUFKIT DATA
SHOWS WINDS TO 40 TO 50 KTS DOWN TO 2K FEET WITH STEEP LAPSE
RATES. THE STRONGEST WINDS ARE LIKELY TO BE IN THE 18Z TO 03Z TIME
FRAME. WINDS GUSTS TO 45 TO 50 MPH ARE CERTAINLY POSSIBLE. EXPECT
THERE WILL BE POWER OUTAGES AS THE DAY GOES ON. TEMPERATURES WILL
RISE ABOUT 5 TO 10 DEGREES TOMORROW WHICH WILL PUT HIGH TEMPS IN
THE 20S MOST EVERYWHERE WITH SOME UPPER TEENS IN THE MOUNTAINS.
THIS IS A GOOD 20 DEGREES BELOW NORMAL. SNOW SHOWERS WILL BE
LIKELY IN THE MOUNTAINS WITH 1 TO 3 INCHES POSSIBLE. FOR SUNDAY
NIGHT WINDS WILL ABATE SOMEWHAT AFTER MIDNIGHT BUT TEMPS WILL
PLUNGE. EXPECT AROUND ZERO IN THE MOUNTAINS AND NEAR 10 AT THE
COAST. RECORD LOW FOR PORTLAND MONDAY IS 9 DEGREES. WILL BE CLOSE
TO THIS.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
RIDGE OF HIGH PRESSURE WILL CREST OVER THE REGION MONDAY BEFORE
SHIFTING OFFSHORE. EXPECT A SUNNY START TO THE DAY BEFORE HIGH
CLOUDS SPILL IN FROM THE WEST IN THE AFTERNOON. WILL BE ANOTHER COLD
ONE WITH HIGHS ONLY REACHING THE UPPER TEENS TO LOWER 20S NORTH AND
MID 20S TO NEAR 30 SOUTH.
AREA OF WEAK OVER-RUNNING AHEAD LOW PRESSURE MOVING THROUGH SOUTHERN
CANADA WILL PUSH IN FROM THE WEST MONDAY NIGHT BRINGING SOME LIGHT
SNOW TO THE REGION. BEST CHANCES OF PRECIP WILL BE IN NORTHERN ZONES
WHERE AN INCH OR TWO OF ACCUMULATION WILL BE POSSIBLE. ELSEWHERE
JUST LOOKING FOR A LIGHT DUSTING. LOOKING FOR LOWS IN THE MID TEENS
TO LOWER 20S.
CLOUDS AND LINGERING FLURRIES WILL GIVE WAY TO PARTLY SUNNY SKIES ON
TUESDAY. COLD FRONT APPROACHING FROM THE WEST MAY BRING SNOW SHOWERS
TO THE MOUNTAINS BY LATE IN THE DAY. SHOULD SEE A MUCH WARMER DAY
WITH TEMPS RANGING THROUGH THE 30S.
COLD FRONT WILL SWING THROUGH THE REGION TUESDAY NIGHT BRINGING A
CHANCE OF SNOW SHOWERS IN THE NORTH AND VARIABLE CLOUDS ACROSS
SOUTHERN AREAS. OVERNIGHT LOWS WILL RANGE THROUGH THE 20S.
MODELS STILL FAR APART ON WEDNESDAY WITH THE ECMWF BRINGING LOW
PRESSURE UP THE EAST COAST AND GFS TAKING THE SAME SYSTEM WELL
OFFSHORE. AT THIS POINT SUPER BLEND GIVING LIKELY POPS WITH A MIX OF
RAIN AND SNOW IN THE SOUTH AND SNOW IN THE FOOTHILLS AND NORTH. SO
POTENTIAL IS STILL THERE FOR SIGNIFICANT SNOW IN THE NORTH AND A
MESSY MIX IN THE SOUTH. HIGH TEMPS WILL RANGE THOUGH THE 30S TO
NEAR 40.
HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE WEST THURSDAY
THROUGH FRIDAY. EXPECT TEMPS ONCE AGAIN BELOW NORMAL THURSDAY AS
COLD CANADIAN AIR FLOODS IN ON A STRONG NORTHERLY WINDS. WILL SEE
TEMPS MODERATE SOMEWHAT ON FRIDAY AS HIGH PRESSURE CRESTS OVER THE
REGION.
&&
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...EXPECT MOSTLY VFR. BRIEF MVFR/IFR PSBL LATE TONIGHT
IN SNOW SHOWERS. HIE WILL SEE MOSTLY MVFR.
LONG TERM...VFR MONDAY THROUGH TUESDAY. IFR/LIFR CEILINGS AND VSBY
DEVELOPING ON WEDNESDAY. VFR THURSDAY.
&&
.MARINE...
SHORT TERM...GALE WARNING HAS BEEN ISSUED.
LONG TERM...GALES POSSIBLE ON WEDNESDAY.
&&
.CLIMATE...
SIGNIFICANT OUTBREAK OF EARLY SEASON COLD AIR WILL CHALLENGE SOME
LOCAL RECORDS OVER THE NEXT COUPLE OF DAYS. AT KPWM THE RECORD
COLD MAXIMUM TEMP FOR 11/24 IS 28 SET IN 1989. THE TEMP AROUND
MIDNIGHT TONIGHT WILL LIKELY BE THE WARMEST KPWM GETS ALL
DAY...AND WILL BE VERY CLOSE TO 28 DEG. ON 11/25 KPWM HAS A RECORD
COLD MAXIMUM TEMP OF 29 SET IN 1993. THE CURRENT FORECAST IS FOR A
HIGH TEMP AROUND 30. FOR LOW TEMP ON 11/25...KPWM SET A RECORD IN
2000 OF 9 DEG. THE CURRENT FORECAST IS FOR 11/25 IS A LOW TEMP
AROUND 10 DEG.
A LITTLE COOLER BUT SIMILARLY FOR KCON...THE RECORD COLD MAXIMUM
TEMP FOR 11/24 IS 24 SET IN 1921. WHILE IN 1938 THE RECORD COLD
MAXIMUM TEMP FOR 11/25 WAS SET AT 21. THE RECORD LOW TEMP FOR
11/25 IS 5 DEG SET IN 1956 AND 2000.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WIND ADVISORY FROM 7 AM SUNDAY TO 1 AM EST MONDAY FOR
MEZ007>009-012>014-018>028.
NH...WIND ADVISORY FROM 7 AM SUNDAY TO 1 AM EST MONDAY FOR
NHZ001>010-013-014.
MARINE...GALE WARNING FROM 7 AM SUNDAY TO 7 AM EST MONDAY FOR
ANZ150>154.
&&
$$
NEAR TERM...LEGRO
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
731 PM EST SAT NOV 23 2013
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION TONIGHT WITH A STRONG NORTHWEST
FLOW SETTING UP BEHIND IT. HIGH PRESSURE WILL BUILD SOUTH OF NEW
ENGLAND SUNDAY THROUGH MONDAY. A COLD FRONT WILL SLOWLY APPROACH
FROM THE WEST MONDAY NIGHT AND TUESDAY AND WILL CROSS THE REGION
TUESDAY NIGHT. LOW PRESSURE WILL MOVE UP THE EAST COAST ON
WEDNESDAY. HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE WEST
THURSDAY THROUGH FRIDAY. HIGH PRESSURE WILL CREST OVER THE REGION
ON FRIDAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
UPDATE...NO MAJOR CHANGES WITH THIS FORECAST UPDATE. MOSTLY
TWEAKED POP BASED ON LATEST RADAR TRENDS AND BLENDED WITH THE RAP
AND HRRR OUT THRU THE NEXT 6 HOURS. ARCTIC FNT CONTINUES TO MAKE
PROGRESS TOWARDS THE CWFA...WITH SHARP TRANSITION TO PRES RISES
SOON ACROSS THE WRN ZONES. THIS WILL BRING THE WINDS BACK UP...AS
CAA WILL CONTINUE RIGHT THRU TOMORROW. ONE BAND OF SN SQUALLS AHEAD
OF THIS FNT IS CROSSING SRN NH ATTM...WITH A SECOND AREA ACROSS
NRN VT SET TO DROP THRU THE AREA IN THE NEXT COUPLE OF HOURS.
PREVIOUS DISCUSSION...ARCTIC COLD FNT MAKING QUICK PROGRESS
TOWARDS THE CWFA ATTM. SHSN AND SQUALLS WILL BECOME MORE NUMEROUS
AS IT APPROACHES THIS EVENING. STRONG CAA IS DESTABILIZING THE
LLVLS...ALLOWING SHSN TO BECOME QUITE INTENSE AT TIMES. LOOKING AT
UPSTREAM OBS AND WEBCAMS...VSBYS WILL DROP TO 1/4SM OR LESS AT
TIMES. HAVE ADDED HEAVY SN WORDING TO SRN NH AND ADJACENT SWRN ME
FOR THE NEXT SEVERAL HOURS AS SQUALLS TRACK OVER THESE AREAS.
ADDITIONALLY...ABOVE FREEZING TEMPS TODAY WILL MEAN ROAD TEMPS
WILL BE WARM ENOUGH TO MELT SNFL INITIALLY. HOWEVER...RAPIDLY
FALLING TEMPS WILL MEAN THIS WILL REFREEZE...CREATING VERY ICY
ROADWAYS. SEEING AS THESE SHSN WILL BE CROSSING INTERSTATES
89...93...AND 95 THIS IS A CONCERN. USED A BLEND OF THE LATEST RAP
AND HRRR TO TREND POP OVER THE NEXT FEW HOURS. OTHERWISE FORECAST
LOOKS ON TRACK AS BITTER COLD HEADS TOWARDS THE REGION.
&&
.SHORT TERM /SUNDAY NIGHT/...
FOR SUNDAY WE HAVE ISSUED A WIND ADVISORY. LOOKING AT BUFKIT DATA
SHOWS WINDS TO 40 TO 50 KTS DOWN TO 2K FEET WITH STEEP LAPSE
RATES. THE STRONGEST WINDS ARE LIKELY TO BE IN THE 18Z TO 03Z TIME
FRAME. WINDS GUSTS TO 45 TO 50 MPH ARE CERTAINLY POSSIBLE. EXPECT
THERE WILL BE POWER OUTAGES AS THE DAY GOES ON. TEMPERATURES WILL
RISE ABOUT 5 TO 10 DEGREES TOMORROW WHICH WILL PUT HIGH TEMPS IN
THE 20S MOST EVERYWHERE WITH SOME UPPER TEENS IN THE MOUNTAINS.
THIS IS A GOOD 20 DEGREES BELOW NORMAL. SNOW SHOWERS WILL BE
LIKELY IN THE MOUNTAINS WITH 1 TO 3 INCHES POSSIBLE. FOR SUNDAY
NIGHT WINDS WILL ABATE SOMEWHAT AFTER MIDNIGHT BUT TEMPS WILL
PLUNGE. EXPECT AROUND ZERO IN THE MOUNTAINS AND NEAR 10 AT THE
COAST. RECORD LOW FOR PORTLAND MONDAY IS 9 DEGREES. WILL BE CLOSE
TO THIS.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
RIDGE OF HIGH PRESSURE WILL CREST OVER THE REGION MONDAY BEFORE
SHIFTING OFFSHORE. EXPECT A SUNNY START TO THE DAY BEFORE HIGH
CLOUDS SPILL IN FROM THE WEST IN THE AFTERNOON. WILL BE ANOTHER COLD
ONE WITH HIGHS ONLY REACHING THE UPPER TEENS TO LOWER 20S NORTH AND
MID 20S TO NEAR 30 SOUTH.
AREA OF WEAK OVER-RUNNING AHEAD LOW PRESSURE MOVING THROUGH SOUTHERN
CANADA WILL PUSH IN FROM THE WEST MONDAY NIGHT BRINGING SOME LIGHT
SNOW TO THE REGION. BEST CHANCES OF PRECIP WILL BE IN NORTHERN ZONES
WHERE AN INCH OR TWO OF ACCUMULATION WILL BE POSSIBLE. ELSEWHERE
JUST LOOKING FOR A LIGHT DUSTING. LOOKING FOR LOWS IN THE MID TEENS
TO LOWER 20S.
CLOUDS AND LINGERING FLURRIES WILL GIVE WAY TO PARTLY SUNNY SKIES ON
TUESDAY. COLD FRONT APPROACHING FROM THE WEST MAY BRING SNOW SHOWERS
TO THE MOUNTAINS BY LATE IN THE DAY. SHOULD SEE A MUCH WARMER DAY
WITH TEMPS RANGING THROUGH THE 30S.
COLD FRONT WILL SWING THROUGH THE REGION TUESDAY NIGHT BRINGING A
CHANCE OF SNOW SHOWERS IN THE NORTH AND VARIABLE CLOUDS ACROSS
SOUTHERN AREAS. OVERNIGHT LOWS WILL RANGE THROUGH THE 20S.
MODELS STILL FAR APART ON WEDNESDAY WITH THE ECMWF BRINGING LOW
PRESSURE UP THE EAST COAST AND GFS TAKING THE SAME SYSTEM WELL
OFFSHORE. AT THIS POINT SUPER BLEND GIVING LIKELY POPS WITH A MIX OF
RAIN AND SNOW IN THE SOUTH AND SNOW IN THE FOOTHILLS AND NORTH. SO
POTENTIAL IS STILL THERE FOR SIGNIFICANT SNOW IN THE NORTH AND A
MESSY MIX IN THE SOUTH. HIGH TEMPS WILL RANGE THOUGH THE 30S TO
NEAR 40.
HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE WEST THURSDAY
THROUGH FRIDAY. EXPECT TEMPS ONCE AGAIN BELOW NORMAL THURSDAY AS
COLD CANADIAN AIR FLOODS IN ON A STRONG NORTHERLY WINDS. WILL SEE
TEMPS MODERATE SOMEWHAT ON FRIDAY AS HIGH PRESSURE CRESTS OVER THE
REGION.
&&
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...EXPECT MOSTLY VFR. BRIEF MVFR/IFR PSBL LATE TONIGHT
IN SNOW SHOWERS. HIE WILL SEE MOSTLY MVFR.
LONG TERM...VFR MONDAY THROUGH TUESDAY. IFR/LIFR CEILINGS AND VSBY
DEVELOPING ON WEDNESDAY. VFR THURSDAY.
&&
.MARINE...
SHORT TERM...GALE WARNING HAS BEEN ISSUED.
LONG TERM...GALES POSSIBLE ON WEDNESDAY.
&&
.CLIMATE...
SIGNIFICANT OUTBREAK OF EARLY SEASON COLD AIR WILL CHALLENGE SOME
LOCAL RECORDS OVER THE NEXT COUPLE OF DAYS. AT KPWM THE RECORD
COLD MAXIMUM TEMP FOR 11/24 IS 28 SET IN 1989. THE TEMP AROUND
MIDNIGHT TONIGHT WILL LIKELY BE THE WARMEST KPWM GETS ALL
DAY...AND WILL BE VERY CLOSE TO 28 DEG. ON 11/25 KPWM HAS A RECORD
COLD MAXIMUM TEMP OF 29 SET IN 1993. THE CURRENT FORECAST IS FOR A
HIGH TEMP AROUND 30. FOR LOW TEMP ON 11/25...KPWM SET A RECORD IN
2000 OF 9 DEG. THE CURRENT FORECAST IS FOR 11/25 IS A LOW TEMP
AROUND 10 DEG.
SIMILARLY FOR KCON...RECORD COLD MAXIMUM TEMP FOR 11/24 IS 27 SET
IN 2000. WHILE IN 1993 THE RECORD COLD MAXIMUM TEMP WAS SET AT 29.
THE RECORD LOW TEMP FOR 11/25 IS 5 DEG SET IN 1956 AND 2000.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WIND ADVISORY FROM 7 AM SUNDAY TO 1 AM EST MONDAY FOR
MEZ007>009-012>014-018>028.
NH...WIND ADVISORY FROM 7 AM SUNDAY TO 1 AM EST MONDAY FOR
NHZ001>010-013-014.
MARINE...GALE WARNING FROM 7 AM SUNDAY TO 7 AM EST MONDAY FOR
ANZ150>154.
&&
$$
NEAR TERM...LEGRO
AREA FORECAST DISCUSSION
NWS CARIBOU ME
620 AM EST FRI NOV 22 2013
.SYNOPSIS...
A WEAK WAVE OF LOW PRESSURE WILL APPROACH TODAY AND CROSS THE AREA
TONIGHT. HIGH PRESSURE WILL BUILD IN FROM THE WEST OVER THE
WEEKEND AS LOW PRESSURE STRENGTHENING IN EASTERN CANADA PULLS ARCTIC
AIR INTO THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
620 AM UPDATE...THERE IS AN AREA OF OVERRUNNING PRECIPITATION
ACROSS CENTRAL AND EASTERN NY STATE INTO WESTERN NEW ENGLAND.
THIS IS ASSOCIATED WITH A WEAK WARM FRONT. THE HRRR HAS A PRETTY
GOOD HANDLE ON THE PRECIP SHIELD AS OF 11Z. THE AREA OF
PRECIPITATION IS EXPECTED TO PASS TO THE SOUTH OF THE AREA THIS
MORNING. FOR OUR CWA THE MAIN SYSTEM STILL LOOKS TO BE FROM LATE
THIS EVENING THROUGH THE EARLY MORNING HOURS SATURDAY. MADE SOME
MINOR ADJUSTMENTS TO THE GRIDS BASED ON THE LATEST CONDITIONS...MAINLY
TO INCREASE THE CLOUD COVER THIS MORNING...BUT OVERALL ONLY SOME
MINOR TWEAKS.
PREVIOUS DISCUSSION...
HIGH PRESSURE CONTINUES TO RETREAT TO THE SOUTH OF THE REGION
EARLY THIS MORNING. LOW PRESSURE IS EXPECTED TO DEEPEN TODAY IN
DIFFLUENT FLOW ALOFT ACROSS QUEBEC WITH THE LOW TO BE WEST OF THE
ST LAWRENCE BY 00Z THIS EVENING. THE LOW WILL CONTINUE TO DEEPEN
TONIGHT AS IT PASSES NORTH OF MAINE. THIS WILL BRING A PERIOD OF
OVERRUNNING ACROSS THE NORTHERN AND WESTERN ZONES. THE BUFKIT
SOUNDINGS FROM BOTH THE NAM AND GFS INDICATE A SMALL LAYER ABOVE
FREEZING DURING THE EVENING BUT WITH MOST OF THE QPF TO BE LATER
IN THE EVENING AND OVERNIGHT ANY SCATTERED RAIN SHOWERS WILL
QUICKLY CHANGE TO SNOW. THE HIGHEST SNOW ACCUMULATION IS EXPECTED
ACROSS THE ST JOHN VALLEY WHERE SNOW ACCUMULATION OF AROUND 3
INCHES IS EXPECTED. AMOUNTS IN THE CARIBOU/PRESQUE ISLE AREAS ARE
EXPECTED TO BE AROUND 2 INCHES...AND THEN DROP OFF TO AROUND 1
INCH IN THE HOULTON AREA...WITH LITTLE/NO SNOW ACCUMULATION SOUTH
OF MILLINOCKET. IT LOOKS TO BE JUST SHY OF AN ADVISORY EVENT IN
THE ST JOHN VALLEY. WITH MOST OF THE SNOW FALLING AT NIGHT AND
HEADING INTO A SATURDAY MORNING WILL NOT HOIST ANY ADVISORIES.
THIS AREA ALSO ALREADY HAD A 3 TO 4 INCH SNOWFALL BACK IN OCTOBER.
THE COLD FRONT ASSOCIATED WITH THE LOW SWEEPS ACROSS THE AREA LATE
TONIGHT WITH A GUSTY NORTHWEST WIND TO KICK IN TOWARD MORNING THAT
MAY CAUSE THE SNOW TO BLOW AROUND SOME IN THE FAR NORTH.
TEMPERATURES TODAY WILL BE A BIT COOLER THAN YESTERDAY DESPITE A
WARMER START TO THE DAY. THERE WILL BE A BIT OF COOLING ALOFT IN
THE WAKE OF THE WEAK SURFACE TROUGH MOVING THROUGH OVERNIGHT. ALSO
AN INCREASE IN CLOUDS THIS AFTERNOON WILL CUT OFF THE HEATING.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
SOME VERY BLUSTERY AND COLD WEATHER IS ON THE WAY FOR THIS WEEKEND.
AN UPPER LEVEL TROUGH MOVING INTO THE AREA COMBINED WITH LOW
PRESSURE IN THE MARITIMES AND A LARGE HIGH BUILDING INTO THE NATIONS
MID SECTION WILL BRING GUSTY NORTHWEST WINDS ON SATURDAY. SOME
FLURRIES WILL BE POSSIBLE IN NORTHERN AND WESTERN AREAS. OTHERWISE
SATURDAY WILL BE PARTLY CLOUDY AND CHILLY WITH HIGHS A COUPLE
DEGREES BELOW FREEZING NORTH TO NEAR 40 DOWNEAST. A WEAK
SHORTWAVE WILL SLIDE SOUTH OF THE REGION SATURDAY NIGHT. THE
GRADIENT WILL THEN TIGHTEN BETWEEN LOW PRESSURE IN EASTERN CANADA
AND THE HIGH BUILDING IN. A STRONG GUSTY NORTHWEST WIND WILL
USHER IN EVEN COLDER AIR ON SUNDAY. HIGHS WILL LIKELY BE IN THE 20S
ACROSS THE ENTIRE REGION AND WIND CHILLS MAY REMAIN IN THE SINGLE
DIGITS ALL DAY OVER MUCH OF THE AREA. MOISTURE POOLED IN THE
UPPER TROUGH WILL LIKELY BRING SNOW SHOWERS AND POSSIBLY SOME SNOW
SQUALLS TO NORTHERN AND WESTERN AREAS ON SUNDAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
COLD GUSTY WINDS WILL LIKELY CONTINUE SUNDAY NIGHT WITH LOW PRESSURE
REMAINING IN THE NORTHERN MARITIMES. FLURRIES AND SNOW SHOWERS MAY
CONTINUE ACROSS THE NORTH AND WEST. A SMALL SHORTWAVE RIDGE OF HIGH
PRESSURE WILL THEN MOVE IN ON MONDAY BRINGING A MOSTLY SUNNY DAY. A
NEW SHORTWAVE TROUGH AND WEAK SURFACE LOW MOVING ACROSS SOUTHERN
QUEBEC ON TUESDAY WILL BRING CLOUDS AND A CHANCE FOR A PERIOD OF
LIGHT SNOW OR SNOW SHOWERS TUESDAY, ESPECIALLY ACROSS THE NORTH. OUR
ATTENTION THEN FOCUSES ON A LARGE STORM SYSTEM MOVING THROUGH THE
DEEP SOUTH TUESDAY AND ONTO THE SOUTHEAST COAST TUESDAY NIGHT.
MODELS CONTINUE TO SHOW VARIATION ON THE TRACK OF THIS STORM, BUT
ARE COMING INTO AGREEMENT ON THE POTENTIAL THAT THIS SYSTEM WILL
MOVE UP THE COAST BRINGING A SIGNIFICANT PRECIPITATION EVENT. A
TRACK JUST EAST OF CAPE COD AND INTO THE GULF OF MAINE WOULD BRING
SNOW AND WIND TO NORTHERN AREAS AND SNOW OR SLEET GOING OVER TO
RAIN DOWNEAST. THIS ALL DEPENDS ON THE TIMING OF A NEW TROUGH OF
LOW PRESSURE DIGGING INTO THE PLAINS STATES AS THE SOUTHERN LOW
MOVES ONTO THE EAST COAST. IF THE TROUGH DIGS IN TOO QUICKLY THE
SOUTHERN LOW MAY BE PUSHED OUT TO SEA WHICH IS WHAT EARLIER GFS
MODELS WERE FORECASTING. IF THE TROUGH DIGS IN TOO SLOW THE LOW
MAY TAKE A MORE WESTERN TRACK AND BRING RAIN TO THE ENTIRE REGION
WHICH IS WHAT THE OLD ECMWF HAS BEEN FORECASTING. EITHER WAY,
THERE IS A POTENTIAL FOR A SIGNIFICANT STORM DURING THE MID WEEK
PERIOD AND THOSE WITH TRAVEL PLANS SHOULD STAY TUNED TO FORECAST
UPDATES THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
NEAR TERM: VFR TODAY AT ALL TERMINALS. CONDITION WILL LOWER TO
IFR/LOW END MVFR IN SNOW TONIGHT AT THE NORTHERN TERMINALS...AND
TO MVFR AT THE SOUTHERN TERMINALS IN RAIN/SNOW SHOWERS.
SHORT TERM: VFR CONDITIONS ARE EXPECTED DOWNEAST OVER THE WEEKEND
WITH MVFR CONDITIONS IN SNOW SHOWERS ACROSS THE NORTH. VFR
CONDITIONS ARE EXPECTED TUESDAY AS A WEAK HIGH MOVES OVER.
CONDITIONS WILL THEN LOWER TO MVFR, AND POSSIBLY IFR ACROSS THE
NORTH ON TUESDAY. VFR CONDITIONS EARLY WEDNESDAY MAY DROP TO IFR
FROM SOUTH TO NORTH AS CLOUDS AND PRECIPITATION MOVE IN.
&&
.MARINE...
NEAR TERM: COLD AIR ADVECTION KICKS IN ALONG THE COASTAL WATERS EARLY
SATURDAY MORNING AND HAVE STARTED A SCA AT 10Z. EXPECT FREQUENT
GUSTS TO 30 KT AND A FEW GUSTS TO AROUND 35 KTS.
SHORT TERM: A GALE MAY BE NEEDED SATURDAY MORNING. GALES WILL THEN
LIKELY BE NEEDED FOR COLD GUSTY NORTHWEST WINDS SUNDAY INTO SUNDAY
NIGHT. WINDS MAY DIMINISH TO SCA VALUES MONDAY INTO EARLY
WEDNESDAY BEFORE GALES RETURN LATE WEDNESDAY INTO WEDNESDAY NIGHT
IN A STORM SYSTEM MOVING UP THE COAST.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 5 AM TO 7 PM EST SATURDAY FOR
ANZ050>052.
&&
$$
NEAR TERM...CB
SHORT TERM...BLOOMER
LONG TERM...BLOOMER
AVIATION...CB/BLOOMER
MARINE...CB/BLOOMER
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1237 PM EST FRI NOV 22 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 444 AM EST FRI NOV 22 2013
BROAD AREA OF LIGHT SNOW ASSOCIATED WITH A COUPLED UPPER
JET...SHORTWAVE ENERGY AND MID-LEVEL Q-VECTOR CONVERGENCE CONTINUES
TO SLIDE EAST EARLY THIS MORNING ACROSS UPPER MICHIGAN AND
WISCONSIN. GENERALLY LIGHT SNOW WITH VISIBILITIES IN MOST LOCATIONS
OF 2 TO 5 MILES. WE SAW FINE FLAKES AT OUR OFFICE MOST OF THE
NIGHT...WHICH HAS BEEN HELPFUL IN REDUCING VISIBILITIES. ONE REPORT
FROM NORTHERN WISCONSIN INDICATED A HALF AN INCH OF SNOW
ACCUMULATION AND OUR OFFICE HAD 0.6 INCH AS OF 1AM. THE SNOW HAS
ALREADY ENDED OVER WESTERN UPPER MICHIGAN (KCMX/KIWD OBS) AND
STARTING TO SEE THE REFLECTIVITIES QUICKLY DIMINISH OVER BARAGA
AND IRON COUNTIES. AS THE UPPER LEVEL FEATURES CONTINUE TO SHIFT
EAST THIS MORNING...EXPECT THE SYNOPTIC SNOWFALL TO QUICKLY
DIMINISH THROUGH MID MORNING.
OVER NORTHERN UPPER MICHIGAN...LOW LEVEL 925-850MB NORTH-NORTHWEST
FLOW (ON KMQT VAD AND RAP ANALYSIS) ACROSS LAKE SUPERIOR...ALONG
WITH 850MB TEMPS OF -7C TO -11C FROM EAST TO WEST HAS LED TO SOME
LAKE ENHANCEMENT EARLY THIS MORNING...WITH THE STRONGEST RETURNS ON
RADAR AND OBS INDICATING THE HEAVIEST SNOW OVER EASTERN
MARQUETTE AND WESTERN ALGER COUNTIES. THIS ENHANCEMENT
WILL ALSO BE DIMINISHING QUICKLY THIS MORNING AS A HIGH PRESSURE
RIDGE FROM NORTHERN MINNESOTA NOSES INTO THE AREA. VERY DRY AIR
ABOVE THE INVERSION AT 920MB ON THE 00Z KINL SOUNDING WILL BE WHAT
IS MOVING INTO THE AREA AND REALLY DIMINISH THE INTENSITY OF THE
LAKE ENHANCEMENT OVER THE NORTH CENTRAL THIS MORNING. THIS WILL ALSO
LEAD TO A DIMINISHING TREND TO THE LAKE EFFECT CLOUDS FROM WEST TO
EAST TODAY AS THE LAKE INDUCED INSTABILITY AND MOISTURE IS PINCHED
BY THAT LOWERING INVERSION FROM THE HIGH PRESSURE RIDGE. EXPECT THE
LAKE CLOUDS TO HANG ON THE LONGEST OVER THE KEWEENAW AND THE EAST
WHERE THE BACKING WINDS WINDS WILL STAY FAVORABLE THE LONGEST. THE
REST OF THE AREA SHOULD SEE SKIES BECOMING PARTLY CLOUDY IF NOT
MOSTLY SUNNY LATE THIS MORNING THROUGH THE AFTERNOON.
FOCUS THEN TURNS TO THE MAIN WEATHER MAKER FOR THE FORECAST
PERIOD...WHICH IS ASSOCIATED WITH A LOW THAT IS CURRENTLY LOCATED
NEAR LAKE WINNIPEG. THIS LOW AND POTENT SHORTWAVE NOTED ON WV
IMAGERY WILL QUICKLY SWEEP SOUTHEAST ACROSS LAKE SUPERIOR LATE THIS
AFTERNOON AND EVENING. STRONG CONVERGENCE ALONG TWO ASSOCIATED
TROUGHS WILL LEAD TO A COUPLE MODERATE TO POTENTIALLY HEAVY PERIODS
OF SNOW BEFORE THE LAKE EFFECT REALLY KICKS IN OVERNIGHT.
THE FIRST TROUGH WILL SHIFT WINDS TO THE NORTHWEST AND MOVE INTO THE
KEWEENAW AND WESTERN UPPER MICHIGAN AROUND DINNER TIME AND THE REST
OF THE CWA DURING THE EVENING HOURS. EXPECT THE STRONGEST SNOW TO
OCCUR OVER THE WEST WITH THE FAVORABLE UPSLOPE WINDS AND LEAD TO A
COUPLE HOUR PERIOD OF STRONG SNOW SHOWERS. THEN THERE MAY BE
A SHORT PERIOD OF LIGHTER SNOW AS THE DEEPER MOISTURE CUTS OUT FOR
A FEW HOURS. THE SECONDARY TROUGH (WITH ANOTHER BURST OF
MODERATE TO HEAVY SNOWFALL) WILL THEN DROP SOUTH ACROSS THE KEWEENAW
AND WESTERN UPPER MICHIGAN AROUND OR SHORTLY AFTER
MIDNIGHT...SHIFTING THE WINDS TO ALMOST NORTHERLY AND THE LAKE
EFFECT SNOW SHOULD REALLY KICK IN. EXPECT A SIMILAR OCCURRENCE
ACROSS THE REST OF NORTHERN UPPER MICHIGAN WITH MORE OF A DELAY ON
THE SECONDARY TROUGH UNTIL THE 08-09Z TIME FRAME. IN ADDITION...WITH
THE FIRST FRONT SHIFTING WINDS TO LESS FAVORABLE NORTHWESTERLY
DOWNSLOPING FLOW FOR THE NORTH CENTRAL...THEY WILL LIKELY NOT SEE
MUCH SNOW ACCUMULATION UNTIL THE SECONDARY TROUGH MOVES THROUGH AND
LAKE EFFECT DEVELOPS.
BEHIND THE TROUGHS...850MB TEMPS WILL FALL FROM AROUND -10C AT 18Z
TODAY TO -20C AT 12Z SATURDAY. THIS WILL PROVIDE SIGNIFICANT OVER
THE LAKE INSTABILITY (DELTA-T VALUES APPROACHING 25) AND LEAD TO
LAKE INDUCED CAPE AND EQL LEVELS OF 800 J/KG AND 13-14K
FT RESPECTIVELY. BEST DEEP MOISTURE WILL BE FOCUSED OVER THE EAST
CLOSER TO THE LOW MOVING THROUGH. THUS...EXPECT REALLY GOOD
CONDITIONS FOR MODERATE TO HEAVY LAKE EFFECT SNOW DURING THE
OVERNIGHT HOURS AND CONTINUING INTO SATURDAY. SNOW RATIOS WILL BE
ON THE INCREASE THROUGH THE FORECAST PERIOD...STARTING AROUND
10-15 TO 1 BEFORE INCREASING TO THE LOW 20S ONCE THE LAKE EFFECT
KICKS IN. WITH THE BEST LAKE INDUCED LIFT RIGHT IN THE DGZ...THERE
IS THE POTENTIAL THAT SNOW RATIOS COULD BE HIGHER IN THE STRONGER
BANDS (ESPECIALLY TOWARDS IRONWOOD WHERE THE WINDS ARE LIGHTER) AND
MAY BE SOMETHING TO MONITOR.
AS FOR SNOW AMOUNTS FOR THE WEST FIRST. WHILE THERE WILL BE SOME
BURSTS LATE THIS AFTERNOON AND EVENING...OVERALL AMOUNTS SHOULD BE
IN THE 1-3 INCH RANGE. THEN AS THE LAKE EFFECT KICKS IN
TONIGHT...HAVE ANOTHER 2-4 INCHES OVER THE HIGHER TERRAIN FROM THE
KEWEENAW THROUGH GOGEBIC COUNTIES. THIS PRODUCES TOTALS BY 12Z
SATURDAY OF 3-7 INCHES...WITH THE HIGHEST FOR GOGEBIC/ONTONAGON
DUE TO THE LONGER FETCH AND WEAKER WINDS INCREASING RESIDENCE
TIME OVER THE LAKE. ALSO...IT APPEARS THE INITIAL TROUGH WILL BECOME
HUNG UP IN THAT AREA THIS EVENING...WHICH WOULD ALLOW THE SNOW TO
PERSIST FOR MUCH OF THE EVENING HOURS. MARQUETTE/BARAGA COUNTY AND
LOCATIONS EASTWARD WILL LIKELY NOT REALLY SEE THE SNOW PICKING UP
UNTIL AFTER MIDNIGHT AND LIKELY AROUND 08-09Z WHEN THE TROUGH
FINALLY SHIFTS THROUGH AND SWITCHES THE WINDS MORE NORTH-NORTHWEST.
THIS BECOMES FAIRLY FAVORABLE FOR NORTH CENTRAL AND EASTERN PARTS OF
MARQUETTE COUNTY AND FOCUSED INTO ALGER COUNTY LATE TONIGHT...SO
EXPECT CONDITIONS TO DETERIORATE VERY QUICKLY THERE. WITH AN INCH
AN HOUR SNOW OVER MARQUETTE COUNTY LATE TONIGHT...EXPECT TOTALS IN
THE 2-5 INCH RANGE FROM THE HURON MOUNTAINS THROUGH
NEGAUNEE/SKANDIA BY 12Z. FARTHER EAST...THE DELAYED ARRIVAL WILL
LIKELY KEEP AMOUNTS IN THE 1-3 INCH RANGE.
ALONG WITH THE SNOW...WINDS WILL ALSO INCREASE BEHIND THE
FRONTS...GUSTING TO 40KT GALES OVER CENTRAL AND EASTERN LAKE
SUPERIOR DURING THE OVERNIGHT HOURS. GUSTS TO 35-40MPH WILL BE
COMMON OVER THE KEWEENAW STARTING LATE THIS EVENING AND LATE
TONIGHT EAST OF MARQUETTE. AS THE SNOW STARTS TO
ACCUMULATE...BLOWING SNOW BECOMES A LARGER ISSUE THROUGH THE NIGHT
AND INTO SATURDAY WITH SNOW BEING ON THE GROUND.
AS FOR HEADLINES...COORDINATION WITH THE LONG TERM SHIFT LED TO
SWITCHING GOGEBIC/ONTONAGON AND ALGER/LUCE...NORTHERN SCHOOLCRAFT
TO LAKE EFFECT SNOW WARNINGS DUE TO THEIR FAVORABLE CONDITIONS AND
EXPECTED SNOW ACCUMULATIONS. THERE WAS ENOUGH UNCERTAINTY ON
SNOWFALL AMOUNTS FOR THE KEWEENAW PENINSULA TO OPT FOR AN ADVISORY
AT THIS POINT...SINCE THE LIMITED FETCH (AND UPSLOPE) WITH THE
WINDS WILL KEEP AMOUNTS LOWER. THOSE WINDS COULD ALSO MAKE FOR
WORSE VISIBILITIES AND COULD ALMOST JUSTIFY A WARNING. MARQUETTE
WAS SIMILAR (AND MAY NEED TO BE UPGRADED WITH THE DAY SHIFT)...SINCE
AMOUNTS IN 12 HOURS ARE JUST UNDER WARNING CRITERIA AND THERE IS
SOME UNCERTAINTY ON THE EXACT LOCATION OF THE STRONGER BANDS OFF
LAKE NIPIGON. FINALLY...THE REST OF THE AREAS IN THE WATCH WERE
SWITCHED TO AN ADVISORY.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 503 AM EST FRI NOV 22 2013
THE MAIN FCST CONCERNS ARE THE LES POTENTIAL FROM SAT INTO EARLY
SUNDAY ALONG WITH BLOWING SNOW AND WIND CHILLS IN THE VERY COLD
ARCTIC AIRMASS.
SAT INTO SAT NIGHT...
WITH MODEL FCST 850MB TEMPS FALLING TO -18 TO -21C BY 12Z
SAT...VIGOROUS NW/NNW FLOW ORIENTED LAKE EFFECT SNOW BANDS WILL BE
ONGOING IN THE WAKE OF THE ARCTIC FRONT. MODELS SUGGEST THAT THE
DEEPER MOISTURE TO AROUND 8K TO 10K FEET WILL PERSIST LONGER OVER
THE ERN FCST AREA. THE FAVORABLE MOISTURE PROFILE AND THE DGZ WITHIN
THE CONVECTIVE LAYER WILL SUPPORT SNOWFALL RATES OF AT LEAST 1 TO 2
INCHES PER HOUR IN THE STRONGER BANDS. HOWEVER...SNOWFLAKE
FRACTURING AND COMPACTION WITH TEH STRONG WINDS SHOULD LIMIT
SNOW/WATER RATIOS TO AROUND 20/1.
AS IS OFTEN THE CASE...THE MOST INTENSE DOMINANT BAND SHOULD
ORIGINATE WITH PRECONDITIONING OFF OF LAKE NIPIGON. THERE IS LESS
CONFIDENCE ON WHERE THAT BAND WILL SET UP AND HOW LONG IT WILL LAST
IN ANY ONE LOCATION. THE HIGHER RESOLUTION MODELS SUGGEST THAT THE
BAND MAY START OUT NEAR MARQUETTE AND THEN SHIFT EAST TOWARD SHOT
POINT AND INTO ALGER COUNTY BY LATE SATURDAY MORNING WHERE THE
HEAVIER LES WILL THEN PERSIST FROM SAT AFTERNOON INTO SAT NIGHT. 12
HOUR SNOWFALL AMOUNTS OF AROUND 8 INCHES ARE EXPECTED BOTH SATURDAY
AND SAT NIGHT FOR ALGER AND NRN SCHOOLCRAFT COUNTIES WHERE LES
WARNINGS WERE POSTED. THERE WAS GREATER UNCERTAINTY FOR MARQUETTE
COUNTY WHERE AN ADVISORY WAS POSTED. SNOWFALL TOTALS SHOULD BE
GREATEST IN THE 6Z-18Z/SAT PERIOD WHEN AMOUNTS IN THE 3 TO 7 INCH RANGE
ARE EXPECTED. AN UPGRADE TO A WARNING MAY BE NEEDED IF ANY STRONG
BANDS PERSIST LONGER THAN EXPECTED.
OVER THE WEST...INVERSION HEIGHTS DROPPING TO AROUND 5K-6K FT WILL
LIMIT LES INTENSITY. HOWEVER...WITH STRONG NRLY UPSLOPE FLOW INTO
THE HIGHER TERRAIN WILL SUPPORT ADDITIONAL SNOWFALL AMOUNTS OF 3 TO
5 INCHES SATURDAY WITH ANOTHER 2 TO 4 INCHES SAT NIGHT.
GUSTY WINDS TO 30-40 MPH WILL ALSO PRODUCE CONSIDERABLE BLOWING SNOW
WITH SHARPLY REDUCED VISIBILITY IN THE HEAVIER SNOW BANDS.
THE LES SHOULD MOSTLY END SUNDAY FROM W TO E AS WINDS BACK TO THE SW
AHEAD OF THE NEXT CLIPPER SHORTWAVE TROUGH DIVING SE THROUGH SOUTH
CNTRL CANADA. HOWEVER...A DEVELOPING WAA PATTERN WITH STRONG
285K-295K ISENTROPIC LIFT WILL PROBABLY LEAD TO AN AREA OF -SN
STREAKING SE INTO THE AREA SUN AFTN/NIGHT. HOWEVER...SINCE THE
STRONGER 700-300 MB QVECTOR CONV REMAINS WELL TO THE NORTH WITH THE
TRACK OF THE SHRTWV AND LOWER LEVELS ARE VERY DRY...ONLY CHANCE POPS
WERE INCLUDED FOR SNOWFALL AMOUNTS THAT WOULD AMOUNT TO LESS THAN AN
INCH OVER MOST OF THE CWA.
TUE-THU...THE GFS/GEFS/ECMWF WERE IN REASONABLE AGREEMENT THAT
ANOTHER BATCH OF ARCTIC AIR IS EXPECTED TO MOVE INTO THE NRN GREAT
LAKES IN THE WAKE OF A STRONGER SHORTWAVE MOVING THROUGH NRN ONTARIO
ON TUE. WITH 850 MB TEMPS DROPPING TO AROUND -17C...ANOTHER EXTENDED
PERIOD OF LES WITH AT LEAST MODERATE ACCUMULATIONS IS LIKELY FOR NW
TO N FLOW FAVORED LOCATIONS. THE LES SHOULD DIMINISH BY THU AS THE
SFC HIGH BUILDS INTO THE AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1236 PM EST FRI NOV 22 2013
A LOW PRESSURE SYSTEM THAT IS JUST NORTHWEST OF LAKE SUPERIOR WILL
DIVE SOUTHEAST ACROSS LAKE SUPERIOR THIS AFTERNOON AND DRAG A COLD
FRONT ACROSS THE AREA LATE THIS AFTERNOON AND EVENING. THERE WILL
LIKELY BE A BRIEF PERIOD OF STRONGER SNOW SHOWERS WITH THIS FRONT
OVER THE WEST...THEN LIGHT TO MODERATE LAKE EFFECT SNOW DURING THE
REST OF THE EVENING WITH MVFR CONDITIONS. BY THE TIME THE FRONT
REACHES KSAW...THE IMPACT FROM THE SNOW SHOWERS WILL BE LIMITED. A
SECONDARY FRONT WILL DROP SOUTH ACROSS THE TAF SITES BETWEEN 06-08Z
AND BRING ANOTHER BURST OF HEAVY SNOW. THIS SNOW WILL TRANSITION TO
LAKE EFFECT UNDER NNW WINDS AND LIKELY BRING ALTERNATE TO NEARLY
AIRFIELD LANDING MINIMUM VISIBILITIES TO THE THREE SITES INTO
SATURDAY MORNING. SHOULD SEE SOME IMPROVEMENT INTO SATURDAY
AFTERNOON AS DRIER AIR WORKS INTO THE IWD AND CMX AREAS AND WINDS
MAY SHIFT BEST LAKE EFFECT SNOW JUST E OF SAW...BUT THERE CONFIDENCE
IN EXACT CIGS AND VIS IS LOW THAT LATE IN THE TAF PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 444 AM EST FRI NOV 22 2013
A FAIRLY ACTIVE NEXT COUPLE DAYS IS IN STORE FOR LAKE SUPERIOR. A
TROUGH THAT MOVED THROUGH LAKE SUPERIOR THIS PAST EVENING WILL
CONTINUE EAST EARLY THIS MORNING...WHILE A HIGH PRESSURE RIDGE
MOVES ACROSS THE LAKE THROUGH EARLY AFTERNOON. THERE WERE A FEW
GALE FORCE GUSTS TO 35KTS SHORTLY AFTER MIDNIGHT...BUT THEY HAVE
SINCE DIMINISHED AND EXPECT A DIMINISHING TREND TO THE WINDS THIS
MORNING. AS THE HIGH PRESSURE RIDGE SHIFTS EAST THIS AFTERNOON
SOUTHWESTERLY WINDS WILL BE ON THE INCREASE OVER WESTERLY LAKE
SUPERIOR AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM. THIS SYSTEM
WILL QUICKLY DIVE SOUTHEAST ACROSS LAKE SUPERIOR LATE THIS AFTERNOON
AND EVENING...QUICKLY SHIFTING WINDS TO THE NORTH-NORTHWEST AND
PRODUCING GALE FORCE WINDS TO 40KTS. THERE COULD EVEN BE SOME GUSTS
TO 45KTS RIGHT AS WINDS SHIFT TO THE NORTH-NORTHWEST AFTER MIDNIGHT
OVER EASTERN LAKE SUPERIOR. THE GALE WARNING THAT IS IN PLACE LOOKS
TO BE IN GOOD SHAPE. A STRONG HIGH DROPPING SOUTH THROUGH THE
NORTHERN PLAINS ON SATURDAY WILL BEGIN TO NOSE A RIDGE OVER WESTERN
LAKE SUPERIOR ON SATURDAY AFTERNOON AND THEN PUSH ACROSS THE ENTIRE
LAKE SATURDAY NIGHT AND SUNDAY. THIS WILL LEAD TO DIMINISHING AND
BACKING WINDS DURING THAT PERIOD. THAT DIMINISHING TREND WILL BE
SHORT LIVED AS WINDS WILL INCREASE ON SUNDAY NIGHT OUT OF THE
SOUTHWEST (TO 30KTS) AHEAD OF LOW MOVING SOUTHEAST THROUGH ONTARIO
LATE SUNDAY NIGHT AND MONDAY. THIS LOW WILL DRAG A COUPLE TROUGHS
ACROSS LAKE SUPERIOR MONDAY AND MONDAY NIGHT...WITH THE SECOND ONE
STALLING OVER SOUTHEAST LAKE SUPERIOR THROUGH WEDNESDAY. AT THIS
POINT...NORTHWEST WINDS UP TO 30KTS ARE EXPECTED BEHIND THE
TROUGHS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 1 AM EST
SUNDAY FOR MIZ004-084.
LAKE EFFECT SNOW WARNING FROM MIDNIGHT TONIGHT TO NOON EST
SUNDAY FOR MIZ006-007-085.
LAKE EFFECT SNOW ADVISORY FROM 5 PM THIS AFTERNOON TO 7 AM EST
SUNDAY FOR MIZ001-003.
LAKE EFFECT SNOW WARNING FROM 6 PM EST /5 PM CST/ THIS EVENING
TO 7 AM EST /6 AM CST/ SUNDAY FOR MIZ002-009.
LAKE EFFECT SNOW ADVISORY FROM 1 AM TO 10 PM EST SATURDAY FOR
MIZ005.
LAKE EFFECT SNOW ADVISORY FROM 1 AM SATURDAY TO 7 AM EST SUNDAY
FOR MIZ014.
LAKE EFFECT SNOW ADVISORY FROM 1 AM SATURDAY TO 5 AM EST SUNDAY
FOR MIZ013.
LAKE SUPERIOR...
GALE WARNING FROM 11 PM THIS EVENING TO 1 AM EST SUNDAY FOR
LSZ266-267.
GALE WARNING FROM 1 AM TO 10 PM EST SATURDAY FOR LSZ248>251-265.
GALE WARNING FROM 10 PM THIS EVENING TO 10 PM EST SATURDAY FOR
LSZ264.
GALE WARNING FROM 10 PM THIS EVENING TO 7 PM EST SATURDAY FOR
LSZ244-245.
GALE WARNING FROM 10 PM THIS EVENING TO 7 AM EST SATURDAY FOR
LSZ242-243.
GALE WARNING FROM 10 PM THIS EVENING TO 10 AM EST SATURDAY FOR
LSZ263.
LAKE MICHIGAN...
GALE WARNING FROM 4 AM TO 10 PM EST SATURDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...SRF
LONG TERM...JLB
AVIATION...TITUS
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
644 AM EST FRI NOV 22 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 444 AM EST FRI NOV 22 2013
BROAD AREA OF LIGHT SNOW ASSOCIATED WITH A COUPLED UPPER
JET...SHORTWAVE ENERGY AND MID-LEVEL Q-VECTOR CONVERGENCE CONTINUES
TO SLIDE EAST EARLY THIS MORNING ACROSS UPPER MICHIGAN AND
WISCONSIN. GENERALLY LIGHT SNOW WITH VISIBILITIES IN MOST LOCATIONS
OF 2 TO 5 MILES. WE SAW FINE FLAKES AT OUR OFFICE MOST OF THE
NIGHT...WHICH HAS BEEN HELPFUL IN REDUCING VISIBILITIES. ONE REPORT
FROM NORTHERN WISCONSIN INDICATED A HALF AN INCH OF SNOW
ACCUMULATION AND OUR OFFICE HAD 0.6 INCH AS OF 1AM. THE SNOW HAS
ALREADY ENDED OVER WESTERN UPPER MICHIGAN (KCMX/KIWD OBS) AND
STARTING TO SEE THE REFLECTIVITIES QUICKLY DIMINISH OVER BARAGA
AND IRON COUNTIES. AS THE UPPER LEVEL FEATURES CONTINUE TO SHIFT
EAST THIS MORNING...EXPECT THE SYNOPTIC SNOWFALL TO QUICKLY
DIMINISH THROUGH MID MORNING.
OVER NORTHERN UPPER MICHIGAN...LOW LEVEL 925-850MB NORTH-NORTHWEST
FLOW (ON KMQT VAD AND RAP ANALYSIS) ACROSS LAKE SUPERIOR...ALONG
WITH 850MB TEMPS OF -7C TO -11C FROM EAST TO WEST HAS LED TO SOME
LAKE ENHANCEMENT EARLY THIS MORNING...WITH THE STRONGEST RETURNS ON
RADAR AND OBS INDICATING THE HEAVIEST SNOW OVER EASTERN
MARQUETTE AND WESTERN ALGER COUNTIES. THIS ENHANCEMENT
WILL ALSO BE DIMINISHING QUICKLY THIS MORNING AS A HIGH PRESSURE
RIDGE FROM NORTHERN MINNESOTA NOSES INTO THE AREA. VERY DRY AIR
ABOVE THE INVERSION AT 920MB ON THE 00Z KINL SOUNDING WILL BE WHAT
IS MOVING INTO THE AREA AND REALLY DIMINISH THE INTENSITY OF THE
LAKE ENHANCEMENT OVER THE NORTH CENTRAL THIS MORNING. THIS WILL ALSO
LEAD TO A DIMINISHING TREND TO THE LAKE EFFECT CLOUDS FROM WEST TO
EAST TODAY AS THE LAKE INDUCED INSTABILITY AND MOISTURE IS PINCHED
BY THAT LOWERING INVERSION FROM THE HIGH PRESSURE RIDGE. EXPECT THE
LAKE CLOUDS TO HANG ON THE LONGEST OVER THE KEWEENAW AND THE EAST
WHERE THE BACKING WINDS WINDS WILL STAY FAVORABLE THE LONGEST. THE
REST OF THE AREA SHOULD SEE SKIES BECOMING PARTLY CLOUDY IF NOT
MOSTLY SUNNY LATE THIS MORNING THROUGH THE AFTERNOON.
FOCUS THEN TURNS TO THE MAIN WEATHER MAKER FOR THE FORECAST
PERIOD...WHICH IS ASSOCIATED WITH A LOW THAT IS CURRENTLY LOCATED
NEAR LAKE WINNIPEG. THIS LOW AND POTENT SHORTWAVE NOTED ON WV
IMAGERY WILL QUICKLY SWEEP SOUTHEAST ACROSS LAKE SUPERIOR LATE THIS
AFTERNOON AND EVENING. STRONG CONVERGENCE ALONG TWO ASSOCIATED
TROUGHS WILL LEAD TO A COUPLE MODERATE TO POTENTIALLY HEAVY PERIODS
OF SNOW BEFORE THE LAKE EFFECT REALLY KICKS IN OVERNIGHT.
THE FIRST TROUGH WILL SHIFT WINDS TO THE NORTHWEST AND MOVE INTO THE
KEWEENAW AND WESTERN UPPER MICHIGAN AROUND DINNER TIME AND THE REST
OF THE CWA DURING THE EVENING HOURS. EXPECT THE STRONGEST SNOW TO
OCCUR OVER THE WEST WITH THE FAVORABLE UPSLOPE WINDS AND LEAD TO A
COUPLE HOUR PERIOD OF STRONG SNOW SHOWERS. THEN THERE MAY BE
A SHORT PERIOD OF LIGHTER SNOW AS THE DEEPER MOISTURE CUTS OUT FOR
A FEW HOURS. THE SECONDARY TROUGH (WITH ANOTHER BURST OF
MODERATE TO HEAVY SNOWFALL) WILL THEN DROP SOUTH ACROSS THE KEWEENAW
AND WESTERN UPPER MICHIGAN AROUND OR SHORTLY AFTER
MIDNIGHT...SHIFTING THE WINDS TO ALMOST NORTHERLY AND THE LAKE
EFFECT SNOW SHOULD REALLY KICK IN. EXPECT A SIMILAR OCCURRENCE
ACROSS THE REST OF NORTHERN UPPER MICHIGAN WITH MORE OF A DELAY ON
THE SECONDARY TROUGH UNTIL THE 08-09Z TIME FRAME. IN ADDITION...WITH
THE FIRST FRONT SHIFTING WINDS TO LESS FAVORABLE NORTHWESTERLY
DOWNSLOPING FLOW FOR THE NORTH CENTRAL...THEY WILL LIKELY NOT SEE
MUCH SNOW ACCUMULATION UNTIL THE SECONDARY TROUGH MOVES THROUGH AND
LAKE EFFECT DEVELOPS.
BEHIND THE TROUGHS...850MB TEMPS WILL FALL FROM AROUND -10C AT 18Z
TODAY TO -20C AT 12Z SATURDAY. THIS WILL PROVIDE SIGNIFICANT OVER
THE LAKE INSTABILITY (DELTA-T VALUES APPROACHING 25) AND LEAD TO
LAKE INDUCED CAPE AND EQL LEVELS OF 800 J/KG AND 13-14K
FT RESPECTIVELY. BEST DEEP MOISTURE WILL BE FOCUSED OVER THE EAST
CLOSER TO THE LOW MOVING THROUGH. THUS...EXPECT REALLY GOOD
CONDITIONS FOR MODERATE TO HEAVY LAKE EFFECT SNOW DURING THE
OVERNIGHT HOURS AND CONTINUING INTO SATURDAY. SNOW RATIOS WILL BE
ON THE INCREASE THROUGH THE FORECAST PERIOD...STARTING AROUND
10-15 TO 1 BEFORE INCREASING TO THE LOW 20S ONCE THE LAKE EFFECT
KICKS IN. WITH THE BEST LAKE INDUCED LIFT RIGHT IN THE DGZ...THERE
IS THE POTENTIAL THAT SNOW RATIOS COULD BE HIGHER IN THE STRONGER
BANDS (ESPECIALLY TOWARDS IRONWOOD WHERE THE WINDS ARE LIGHTER) AND
MAY BE SOMETHING TO MONITOR.
AS FOR SNOW AMOUNTS FOR THE WEST FIRST. WHILE THERE WILL BE SOME
BURSTS LATE THIS AFTERNOON AND EVENING...OVERALL AMOUNTS SHOULD BE
IN THE 1-3 INCH RANGE. THEN AS THE LAKE EFFECT KICKS IN
TONIGHT...HAVE ANOTHER 2-4 INCHES OVER THE HIGHER TERRAIN FROM THE
KEWEENAW THROUGH GOGEBIC COUNTIES. THIS PRODUCES TOTALS BY 12Z
SATURDAY OF 3-7 INCHES...WITH THE HIGHEST FOR GOGEBIC/ONTONAGON
DUE TO THE LONGER FETCH AND WEAKER WINDS INCREASING RESIDENCE
TIME OVER THE LAKE. ALSO...IT APPEARS THE INITIAL TROUGH WILL BECOME
HUNG UP IN THAT AREA THIS EVENING...WHICH WOULD ALLOW THE SNOW TO
PERSIST FOR MUCH OF THE EVENING HOURS. MARQUETTE/BARAGA COUNTY AND
LOCATIONS EASTWARD WILL LIKELY NOT REALLY SEE THE SNOW PICKING UP
UNTIL AFTER MIDNIGHT AND LIKELY AROUND 08-09Z WHEN THE TROUGH
FINALLY SHIFTS THROUGH AND SWITCHES THE WINDS MORE NORTH-NORTHWEST.
THIS BECOMES FAIRLY FAVORABLE FOR NORTH CENTRAL AND EASTERN PARTS OF
MARQUETTE COUNTY AND FOCUSED INTO ALGER COUNTY LATE TONIGHT...SO
EXPECT CONDITIONS TO DETERIORATE VERY QUICKLY THERE. WITH AN INCH
AN HOUR SNOW OVER MARQUETTE COUNTY LATE TONIGHT...EXPECT TOTALS IN
THE 2-5 INCH RANGE FROM THE HURON MOUNTAINS THROUGH
NEGAUNEE/SKANDIA BY 12Z. FARTHER EAST...THE DELAYED ARRIVAL WILL
LIKELY KEEP AMOUNTS IN THE 1-3 INCH RANGE.
ALONG WITH THE SNOW...WINDS WILL ALSO INCREASE BEHIND THE
FRONTS...GUSTING TO 40KT GALES OVER CENTRAL AND EASTERN LAKE
SUPERIOR DURING THE OVERNIGHT HOURS. GUSTS TO 35-40MPH WILL BE
COMMON OVER THE KEWEENAW STARTING LATE THIS EVENING AND LATE
TONIGHT EAST OF MARQUETTE. AS THE SNOW STARTS TO
ACCUMULATE...BLOWING SNOW BECOMES A LARGER ISSUE THROUGH THE NIGHT
AND INTO SATURDAY WITH SNOW BEING ON THE GROUND.
AS FOR HEADLINES...COORDINATION WITH THE LONG TERM SHIFT LED TO
SWITCHING GOGEBIC/ONTONAGON AND ALGER/LUCE...NORTHERN SCHOOLCRAFT
TO LAKE EFFECT SNOW WARNINGS DUE TO THEIR FAVORABLE CONDITIONS AND
EXPECTED SNOW ACCUMULATIONS. THERE WAS ENOUGH UNCERTAINTY ON
SNOWFALL AMOUNTS FOR THE KEWEENAW PENINSULA TO OPT FOR AN ADVISORY
AT THIS POINT...SINCE THE LIMITED FETCH (AND UPSLOPE) WITH THE
WINDS WILL KEEP AMOUNTS LOWER. THOSE WINDS COULD ALSO MAKE FOR
WORSE VISIBILITIES AND COULD ALMOST JUSTIFY A WARNING. MARQUETTE
WAS SIMILAR (AND MAY NEED TO BE UPGRADED WITH THE DAY SHIFT)...SINCE
AMOUNTS IN 12 HOURS ARE JUST UNDER WARNING CRITERIA AND THERE IS
SOME UNCERTAINTY ON THE EXACT LOCATION OF THE STRONGER BANDS OFF
LAKE NIPIGON. FINALLY...THE REST OF THE AREAS IN THE WATCH WERE
SWITCHED TO AN ADVISORY.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 503 AM EST FRI NOV 22 2013
THE MAIN FCST CONCERNS ARE THE LES POTENTIAL FROM SAT INTO EARLY
SUNDAY ALONG WITH BLOWING SNOW AND WIND CHILLS IN THE VERY COLD
ARCTIC AIRMASS.
SAT INTO SAT NIGHT...
WITH MODEL FCST 850MB TEMPS FALLING TO -18 TO -21C BY 12Z
SAT...VIGOROUS NW/NNW FLOW ORIENTED LAKE EFFECT SNOW BANDS WILL BE
ONGOING IN THE WAKE OF THE ARCTIC FRONT. MODELS SUGGEST THAT THE
DEEPER MOISTURE TO AROUND 8K TO 10K FEET WILL PERSIST LONGER OVER
THE ERN FCST AREA. THE FAVORABLE MOISTURE PROFILE AND THE DGZ WITHIN
THE CONVECTIVE LAYER WILL SUPPORT SNOWFALL RATES OF AT LEAST 1 TO 2
INCHES PER HOUR IN THE STRONGER BANDS. HOWEVER...SNOWFLAKE
FRACTURING AND COMPACTION WITH TEH STRONG WINDS SHOULD LIMIT
SNOW/WATER RATIOS TO AROUND 20/1.
AS IS OFTEN THE CASE...THE MOST INTENSE DOMINANT BAND SHOULD
ORIGINATE WITH PRECONDITIONING OFF OF LAKE NIPIGON. THERE IS LESS
CONFIDENCE ON WHERE THAT BAND WILL SET UP AND HOW LONG IT WILL LAST
IN ANY ONE LOCATION. THE HIGHER RESOLUTION MODELS SUGGEST THAT THE
BAND MAY START OUT NEAR MARQUETTE AND THEN SHIFT EAST TOWARD SHOT
POINT AND INTO ALGER COUNTY BY LATE SATURDAY MORNING WHERE THE
HEAVIER LES WILL THEN PERSIST FROM SAT AFTERNOON INTO SAT NIGHT. 12
HOUR SNOWFALL AMOUNTS OF AROUND 8 INCHES ARE EXPECTED BOTH SATURDAY
AND SAT NIGHT FOR ALGER AND NRN SCHOOLCRAFT COUNTIES WHERE LES
WARNINGS WERE POSTED. THERE WAS GREATER UNCERTAINTY FOR MARQUETTE
COUNTY WHERE AN ADVISORY WAS POSTED. SNOWFALL TOTALS SHOULD BE
GREATEST IN THE 6Z-18Z/SAT PERIOD WHEN AMOUNTS IN THE 3 TO 7 INCH RANGE
ARE EXPECTED. AN UPGRADE TO A WARNING MAY BE NEEDED IF ANY STRONG
BANDS PERSIST LONGER THAN EXPECTED.
OVER THE WEST...INVERSION HEIGHTS DROPPING TO AROUND 5K-6K FT WILL
LIMIT LES INTENSITY. HOWEVER...WITH STRONG NRLY UPSLOPE FLOW INTO
THE HIGHER TERRAIN WILL SUPPORT ADDITIONAL SNOWFALL AMOUNTS OF 3 TO
5 INCHES SATURDAY WITH ANOTHER 2 TO 4 INCHES SAT NIGHT.
GUSTY WINDS TO 30-40 MPH WILL ALSO PRODUCE CONSIDERABLE BLOWING SNOW
WITH SHARPLY REDUCED VISIBILITY IN THE HEAVIER SNOW BANDS.
THE LES SHOULD MOSTLY END SUNDAY FROM W TO E AS WINDS BACK TO THE SW
AHEAD OF THE NEXT CLIPPER SHORTWAVE TROUGH DIVING SE THROUGH SOUTH
CNTRL CANADA. HOWEVER...A DEVELOPING WAA PATTERN WITH STRONG
285K-295K ISENTROPIC LIFT WILL PROBABLY LEAD TO AN AREA OF -SN
STREAKING SE INTO THE AREA SUN AFTN/NIGHT. HOWEVER...SINCE THE
STRONGER 700-300 MB QVECTOR CONV REMAINS WELL TO THE NORTH WITH THE
TRACK OF THE SHRTWV AND LOWER LEVELS ARE VERY DRY...ONLY CHANCE POPS
WERE INCLUDED FOR SNOWFALL AMOUNTS THAT WOULD AMOUNT TO LESS THAN AN
INCH OVER MOST OF THE CWA.
TUE-THU...THE GFS/GEFS/ECMWF WERE IN REASONABLE AGREEMENT THAT
ANOTHER BATCH OF ARCTIC AIR IS EXPECTED TO MOVE INTO THE NRN GREAT
LAKES IN THE WAKE OF A STRONGER SHORTWAVE MOVING THROUGH NRN ONTARIO
ON TUE. WITH 850 MB TEMPS DROPPING TO AROUND -17C...ANOTHER EXTENDED
PERIOD OF LES WITH AT LEAST MODERATE ACCUMULATIONS IS LIKELY FOR NW
TO N FLOW FAVORED LOCATIONS. THE LES SHOULD DIMINISH BY THU AS THE
SFC HIGH BUILDS INTO THE AREA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 643 AM EST FRI NOV 22 2013
MVFR CEILINGS WILL GRADUALLY IMPROVE TO VFR THIS MORNING FROM WEST TO
EAST AS A HIGH PRESSURE RIDGE MOVES ACROSS UPPER MICHIGAN. THE MVFR
CEILINGS WILL HOLD ON THE LONGEST AT KCMX AS WINDS BACK AND STILL
REMAIN FAVORABLE FOR LAKE EFFECT CLOUDS.
A LOW PRESSURE SYSTEM THAT IS JUST NORTH OF THE LAKE OF THE WOODS
IN MINNESOTA WILL DIVE SOUTHEAST ACROSS LAKE SUPERIOR THIS
AFTERNOON AND DRAG A COLD FRONT ACROSS THE AREA LATE THIS AFTERNOON
AND EVENING. THERE WILL LIKELY BE A BRIEF PERIOD OF STRONGER SNOW
SHOWERS WITH THIS FRONT OVER THE WEST...THEN LIGHT TO MODERATE LAKE
EFFECT SNOW DURING THE REST OF THE EVENING WITH MVFR CONDITIONS.
BY THE TIME THE FRONT REACHES KSAW...THE IMPACT FROM THE SNOW
SHOWERS WILL BE LIMITED. A SECONDARY FRONT WILL DROP SOUTH ACROSS
THE TAF SITES BETWEEN 06-08Z AND BRING ANOTHER BURST OF HEAVY SNOW.
THIS SNOW WILL TRANSITION TO LAKE EFFECT UNDER NNW WINDS AND LIKELY
BRING ALTERNATE TO NEARLY AIRFIELD LANDING MINIMUM VISIBILITIES TO
THE THREE SITES INTO SATURDAY MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 444 AM EST FRI NOV 22 2013
A FAIRLY ACTIVE NEXT COUPLE DAYS IS IN STORE FOR LAKE SUPERIOR. A
TROUGH THAT MOVED THROUGH LAKE SUPERIOR THIS PAST EVENING WILL
CONTINUE EAST EARLY THIS MORNING...WHILE A HIGH PRESSURE RIDGE
MOVES ACROSS THE LAKE THROUGH EARLY AFTERNOON. THERE WERE A FEW
GALE FORCE GUSTS TO 35KTS SHORTLY AFTER MIDNIGHT...BUT THEY HAVE
SINCE DIMINISHED AND EXPECT A DIMINISHING TREND TO THE WINDS THIS
MORNING. AS THE HIGH PRESSURE RIDGE SHIFTS EAST THIS AFTERNOON
SOUTHWESTERLY WINDS WILL BE ON THE INCREASE OVER WESTERLY LAKE
SUPERIOR AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM. THIS SYSTEM
WILL QUICKLY DIVE SOUTHEAST ACROSS LAKE SUPERIOR LATE THIS AFTERNOON
AND EVENING...QUICKLY SHIFTING WINDS TO THE NORTH-NORTHWEST AND
PRODUCING GALE FORCE WINDS TO 40KTS. THERE COULD EVEN BE SOME GUSTS
TO 45KTS RIGHT AS WINDS SHIFT TO THE NORTH-NORTHWEST AFTER MIDNIGHT
OVER EASTERN LAKE SUPERIOR. THE GALE WARNING THAT IS IN PLACE LOOKS
TO BE IN GOOD SHAPE. A STRONG HIGH DROPPING SOUTH THROUGH THE
NORTHERN PLAINS ON SATURDAY WILL BEGIN TO NOSE A RIDGE OVER WESTERN
LAKE SUPERIOR ON SATURDAY AFTERNOON AND THEN PUSH ACROSS THE ENTIRE
LAKE SATURDAY NIGHT AND SUNDAY. THIS WILL LEAD TO DIMINISHING AND
BACKING WINDS DURING THAT PERIOD. THAT DIMINISHING TREND WILL BE
SHORT LIVED AS WINDS WILL INCREASE ON SUNDAY NIGHT OUT OF THE
SOUTHWEST (TO 30KTS) AHEAD OF LOW MOVING SOUTHEAST THROUGH ONTARIO
LATE SUNDAY NIGHT AND MONDAY. THIS LOW WILL DRAG A COUPLE TROUGHS
ACROSS LAKE SUPERIOR MONDAY AND MONDAY NIGHT...WITH THE SECOND ONE
STALLING OVER SOUTHEAST LAKE SUPERIOR THROUGH WEDNESDAY. AT THIS
POINT...NORTHWEST WINDS UP TO 30KTS ARE EXPECTED BEHIND THE
TROUGHS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 1 AM EST
SUNDAY FOR MIZ004-084.
LAKE EFFECT SNOW WARNING FROM MIDNIGHT TONIGHT TO NOON EST
SUNDAY FOR MIZ006-007-085.
LAKE EFFECT SNOW ADVISORY FROM 5 PM THIS AFTERNOON TO 7 AM EST
SUNDAY FOR MIZ001-003.
LAKE EFFECT SNOW WARNING FROM 6 PM EST /5 PM CST/ THIS EVENING
TO 7 AM EST /6 AM CST/ SUNDAY FOR MIZ002-009.
LAKE EFFECT SNOW ADVISORY FROM 1 AM TO 10 PM EST SATURDAY FOR
MIZ005.
LAKE EFFECT SNOW ADVISORY FROM 1 AM SATURDAY TO 7 AM EST SUNDAY
FOR MIZ014.
LAKE EFFECT SNOW ADVISORY FROM 1 AM SATURDAY TO 5 AM EST SUNDAY
FOR MIZ013.
LAKE SUPERIOR...
GALE WARNING FROM 11 PM THIS EVENING TO 1 AM EST SUNDAY FOR
LSZ266-267.
GALE WARNING FROM 1 AM TO 10 PM EST SATURDAY FOR LSZ248>251-265.
GALE WARNING FROM 10 PM THIS EVENING TO 10 PM EST SATURDAY FOR
LSZ264.
GALE WARNING FROM 10 PM THIS EVENING TO 7 PM EST SATURDAY FOR
LSZ244-245.
GALE WARNING FROM 10 PM THIS EVENING TO 7 AM EST SATURDAY FOR
LSZ242-243.
GALE WARNING FROM 10 PM THIS EVENING TO 10 AM EST SATURDAY FOR
LSZ263.
LAKE MICHIGAN...
GALE WARNING FROM 4 AM TO 10 PM EST SATURDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...SRF
LONG TERM...JLB
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
504 AM EST FRI NOV 22 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 444 AM EST FRI NOV 22 2013
BROAD AREA OF LIGHT SNOW ASSOCIATED WITH A COUPLED UPPER
JET...SHORTWAVE ENERGY AND MID-LEVEL Q-VECTOR CONVERGENCE CONTINUES
TO SLIDE EAST EARLY THIS MORNING ACROSS UPPER MICHIGAN AND
WISCONSIN. GENERALLY LIGHT SNOW WITH VISIBILITIES IN MOST LOCATIONS
OF 2 TO 5 MILES. WE SAW FINE FLAKES AT OUR OFFICE MOST OF THE
NIGHT...WHICH HAS BEEN HELPFUL IN REDUCING VISIBILITIES. ONE REPORT
FROM NORTHERN WISCONSIN INDICATED A HALF AN INCH OF SNOW
ACCUMULATION AND OUR OFFICE HAD 0.6 INCH AS OF 1AM. THE SNOW HAS
ALREADY ENDED OVER WESTERN UPPER MICHIGAN (KCMX/KIWD OBS) AND
STARTING TO SEE THE REFLECTIVITIES QUICKLY DIMINISH OVER BARAGA
AND IRON COUNTIES. AS THE UPPER LEVEL FEATURES CONTINUE TO SHIFT
EAST THIS MORNING...EXPECT THE SYNOPTIC SNOWFALL TO QUICKLY
DIMINISH THROUGH MID MORNING.
OVER NORTHERN UPPER MICHIGAN...LOW LEVEL 925-850MB NORTH-NORTHWEST
FLOW (ON KMQT VAD AND RAP ANALYSIS) ACROSS LAKE SUPERIOR...ALONG
WITH 850MB TEMPS OF -7C TO -11C FROM EAST TO WEST HAS LED TO SOME
LAKE ENHANCEMENT EARLY THIS MORNING...WITH THE STRONGEST RETURNS ON
RADAR AND OBS INDICATING THE HEAVIEST SNOW OVER EASTERN
MARQUETTE AND WESTERN ALGER COUNTIES. THIS ENHANCEMENT
WILL ALSO BE DIMINISHING QUICKLY THIS MORNING AS A HIGH PRESSURE
RIDGE FROM NORTHERN MINNESOTA NOSES INTO THE AREA. VERY DRY AIR
ABOVE THE INVERSION AT 920MB ON THE 00Z KINL SOUNDING WILL BE WHAT
IS MOVING INTO THE AREA AND REALLY DIMINISH THE INTENSITY OF THE
LAKE ENHANCEMENT OVER THE NORTH CENTRAL THIS MORNING. THIS WILL ALSO
LEAD TO A DIMINISHING TREND TO THE LAKE EFFECT CLOUDS FROM WEST TO
EAST TODAY AS THE LAKE INDUCED INSTABILITY AND MOISTURE IS PINCHED
BY THAT LOWERING INVERSION FROM THE HIGH PRESSURE RIDGE. EXPECT THE
LAKE CLOUDS TO HANG ON THE LONGEST OVER THE KEWEENAW AND THE EAST
WHERE THE BACKING WINDS WINDS WILL STAY FAVORABLE THE LONGEST. THE
REST OF THE AREA SHOULD SEE SKIES BECOMING PARTLY CLOUDY IF NOT
MOSTLY SUNNY LATE THIS MORNING THROUGH THE AFTERNOON.
FOCUS THEN TURNS TO THE MAIN WEATHER MAKER FOR THE FORECAST
PERIOD...WHICH IS ASSOCIATED WITH A LOW THAT IS CURRENTLY LOCATED
NEAR LAKE WINNIPEG. THIS LOW AND POTENT SHORTWAVE NOTED ON WV
IMAGERY WILL QUICKLY SWEEP SOUTHEAST ACROSS LAKE SUPERIOR LATE THIS
AFTERNOON AND EVENING. STRONG CONVERGENCE ALONG TWO ASSOCIATED
TROUGHS WILL LEAD TO A COUPLE MODERATE TO POTENTIALLY HEAVY PERIODS
OF SNOW BEFORE THE LAKE EFFECT REALLY KICKS IN OVERNIGHT.
THE FIRST TROUGH WILL SHIFT WINDS TO THE NORTHWEST AND MOVE INTO THE
KEWEENAW AND WESTERN UPPER MICHIGAN AROUND DINNER TIME AND THE REST
OF THE CWA DURING THE EVENING HOURS. EXPECT THE STRONGEST SNOW TO
OCCUR OVER THE WEST WITH THE FAVORABLE UPSLOPE WINDS AND LEAD TO A
COUPLE HOUR PERIOD OF STRONG SNOW SHOWERS. THEN THERE MAY BE
A SHORT PERIOD OF LIGHTER SNOW AS THE DEEPER MOISTURE CUTS OUT FOR
A FEW HOURS. THE SECONDARY TROUGH (WITH ANOTHER BURST OF
MODERATE TO HEAVY SNOWFALL) WILL THEN DROP SOUTH ACROSS THE KEWEENAW
AND WESTERN UPPER MICHIGAN AROUND OR SHORTLY AFTER
MIDNIGHT...SHIFTING THE WINDS TO ALMOST NORTHERLY AND THE LAKE
EFFECT SNOW SHOULD REALLY KICK IN. EXPECT A SIMILAR OCCURRENCE
ACROSS THE REST OF NORTHERN UPPER MICHIGAN WITH MORE OF A DELAY ON
THE SECONDARY TROUGH UNTIL THE 08-09Z TIME FRAME. IN ADDITION...WITH
THE FIRST FRONT SHIFTING WINDS TO LESS FAVORABLE NORTHWESTERLY
DOWNSLOPING FLOW FOR THE NORTH CENTRAL...THEY WILL LIKELY NOT SEE
MUCH SNOW ACCUMULATION UNTIL THE SECONDARY TROUGH MOVES THROUGH AND
LAKE EFFECT DEVELOPS.
BEHIND THE TROUGHS...850MB TEMPS WILL FALL FROM AROUND -10C AT 18Z
TODAY TO -20C AT 12Z SATURDAY. THIS WILL PROVIDE SIGNIFICANT OVER
THE LAKE INSTABILITY (DELTA-T VALUES APPROACHING 25) AND LEAD TO
LAKE INDUCED CAPE AND EQL LEVELS OF 800 J/KG AND 13-14K
FT RESPECTIVELY. BEST DEEP MOISTURE WILL BE FOCUSED OVER THE EAST
CLOSER TO THE LOW MOVING THROUGH. THUS...EXPECT REALLY GOOD
CONDITIONS FOR MODERATE TO HEAVY LAKE EFFECT SNOW DURING THE
OVERNIGHT HOURS AND CONTINUING INTO SATURDAY. SNOW RATIOS WILL BE
ON THE INCREASE THROUGH THE FORECAST PERIOD...STARTING AROUND
10-15 TO 1 BEFORE INCREASING TO THE LOW 20S ONCE THE LAKE EFFECT
KICKS IN. WITH THE BEST LAKE INDUCED LIFT RIGHT IN THE DGZ...THERE
IS THE POTENTIAL THAT SNOW RATIOS COULD BE HIGHER IN THE STRONGER
BANDS (ESPECIALLY TOWARDS IRONWOOD WHERE THE WINDS ARE LIGHTER) AND
MAY BE SOMETHING TO MONITOR.
AS FOR SNOW AMOUNTS FOR THE WEST FIRST. WHILE THERE WILL BE SOME
BURSTS LATE THIS AFTERNOON AND EVENING...OVERALL AMOUNTS SHOULD BE
IN THE 1-3 INCH RANGE. THEN AS THE LAKE EFFECT KICKS IN
TONIGHT...HAVE ANOTHER 2-4 INCHES OVER THE HIGHER TERRAIN FROM THE
KEWEENAW THROUGH GOGEBIC COUNTIES. THIS PRODUCES TOTALS BY 12Z
SATURDAY OF 3-7 INCHES...WITH THE HIGHEST FOR GOGEBIC/ONTONAGON
DUE TO THE LONGER FETCH AND WEAKER WINDS INCREASING RESIDENCE
TIME OVER THE LAKE. ALSO...IT APPEARS THE INITIAL TROUGH WILL BECOME
HUNG UP IN THAT AREA THIS EVENING...WHICH WOULD ALLOW THE SNOW TO
PERSIST FOR MUCH OF THE EVENING HOURS. MARQUETTE/BARAGA COUNTY AND
LOCATIONS EASTWARD WILL LIKELY NOT REALLY SEE THE SNOW PICKING UP
UNTIL AFTER MIDNIGHT AND LIKELY AROUND 08-09Z WHEN THE TROUGH
FINALLY SHIFTS THROUGH AND SWITCHES THE WINDS MORE NORTH-NORTHWEST.
THIS BECOMES FAIRLY FAVORABLE FOR NORTH CENTRAL AND EASTERN PARTS OF
MARQUETTE COUNTY AND FOCUSED INTO ALGER COUNTY LATE TONIGHT...SO
EXPECT CONDITIONS TO DETERIORATE VERY QUICKLY THERE. WITH AN INCH
AN HOUR SNOW OVER MARQUETTE COUNTY LATE TONIGHT...EXPECT TOTALS IN
THE 2-5 INCH RANGE FROM THE HURON MOUNTAINS THROUGH
NEGAUNEE/SKANDIA BY 12Z. FARTHER EAST...THE DELAYED ARRIVAL WILL
LIKELY KEEP AMOUNTS IN THE 1-3 INCH RANGE.
ALONG WITH THE SNOW...WINDS WILL ALSO INCREASE BEHIND THE
FRONTS...GUSTING TO 40KT GALES OVER CENTRAL AND EASTERN LAKE
SUPERIOR DURING THE OVERNIGHT HOURS. GUSTS TO 35-40MPH WILL BE
COMMON OVER THE KEWEENAW STARTING LATE THIS EVENING AND LATE
TONIGHT EAST OF MARQUETTE. AS THE SNOW STARTS TO
ACCUMULATE...BLOWING SNOW BECOMES A LARGER ISSUE THROUGH THE NIGHT
AND INTO SATURDAY WITH SNOW BEING ON THE GROUND.
AS FOR HEADLINES...COORDINATION WITH THE LONG TERM SHIFT LED TO
SWITCHING GOGEBIC/ONTONAGON AND ALGER/LUCE...NORTHERN SCHOOLCRAFT
TO LAKE EFFECT SNOW WARNINGS DUE TO THEIR FAVORABLE CONDITIONS AND
EXPECTED SNOW ACCUMULATIONS. THERE WAS ENOUGH UNCERTAINTY ON
SNOWFALL AMOUNTS FOR THE KEWEENAW PENINSULA TO OPT FOR AN ADVISORY
AT THIS POINT...SINCE THE LIMITED FETCH (AND UPSLOPE) WITH THE
WINDS WILL KEEP AMOUNTS LOWER. THOSE WINDS COULD ALSO MAKE FOR
WORSE VISIBILITIES AND COULD ALMOST JUSTIFY A WARNING. MARQUETTE
WAS SIMILAR (AND MAY NEED TO BE UPGRADED WITH THE DAY SHIFT)...SINCE
AMOUNTS IN 12 HOURS ARE JUST UNDER WARNING CRITERIA AND THERE IS
SOME UNCERTAINTY ON THE EXACT LOCATION OF THE STRONGER BANDS OFF
LAKE NIPIGON. FINALLY...THE REST OF THE AREAS IN THE WATCH WERE
SWITCHED TO AN ADVISORY.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 503 AM EST FRI NOV 22 2013
THE MAIN FCST CONCERNS ARE THE LES POTENTIAL FROM SAT INTO EARLY
SUNDAY ALONG WITH BLOWING SNOW AND WIND CHILLS IN THE VERY COLD
ARCTIC AIRMASS.
SAT INTO SAT NIGHT...
WITH MODEL FCST 850MB TEMPS FALLING TO -18 TO -21C BY 12Z
SAT...VIGOROUS NW/NNW FLOW ORIENTED LAKE EFFECT SNOW BANDS WILL BE
ONGOING IN THE WAKE OF THE ARCTIC FRONT. MODELS SUGGEST THAT THE
DEEPER MOISTURE TO AROUND 8K TO 10K FEET WILL PERSIST LONGER OVER
THE ERN FCST AREA. THE FAVORABLE MOISTURE PROFILE AND THE DGZ WITHIN
THE CONVECTIVE LAYER WILL SUPPORT SNOWFALL RATES OF AT LEAST 1 TO 2
INCHES PER HOUR IN THE STRONGER BANDS. HOWEVER...SNOWFLAKE
FRACTURING AND COMPACTION WITH TEH STRONG WINDS SHOULD LIMIT
SNOW/WATER RATIOS TO AROUND 20/1.
AS IS OFTEN THE CASE...THE MOST INTENSE DOMINANT BAND SHOULD
ORIGINATE WITH PRECONDITIONING OFF OF LAKE NIPIGON. THERE IS LESS
CONFIDENCE ON WHERE THAT BAND WILL SET UP AND HOW LONG IT WILL LAST
IN ANY ONE LOCATION. THE HIGHER RESOLUTION MODELS SUGGEST THAT THE
BAND MAY START OUT NEAR MARQUETTE AND THEN SHIFT EAST TOWARD SHOT
POINT AND INTO ALGER COUNTY BY LATE SATURDAY MORNING WHERE THE
HEAVIER LES WILL THEN PERSIST FROM SAT AFTERNOON INTO SAT NIGHT. 12
HOUR SNOWFALL AMOUNTS OF AROUND 8 INCHES ARE EXPECTED BOTH SATURDAY
AND SAT NIGHT FOR ALGER AND NRN SCHOOLCRAFT COUNTIES WHERE LES
WARNINGS WERE POSTED. THERE WAS GREATER UNCERTAINTY FOR MARQUETTE
COUNTY WHERE AN ADVISORY WAS POSTED. SNOWFALL TOTALS SHOULD BE
GREATEST IN THE 6Z-18Z/SAT PERIOD WHEN AMOUNTS IN THE 3 TO 7 INCH RANGE
ARE EXPECTED. AN UPGRADE TO A WARNING MAY BE NEEDED IF ANY STRONG
BANDS PERSIST LONGER THAN EXPECTED.
OVER THE WEST...INVERSION HEIGHTS DROPPING TO AROUND 5K-6K FT WILL
LIMIT LES INTENSITY. HOWEVER...WITH STRONG NRLY UPSLOPE FLOW INTO
THE HIGHER TERRAIN WILL SUPPORT ADDITIONAL SNOWFALL AMOUNTS OF 3 TO
5 INCHES SATURDAY WITH ANOTHER 2 TO 4 INCHES SAT NIGHT.
GUSTY WINDS TO 30-40 MPH WILL ALSO PRODUCE CONSIDERABLE BLOWING SNOW
WITH SHARPLY REDUCED VISIBILITY IN THE HEAVIER SNOW BANDS.
THE LES SHOULD MOSTLY END SUNDAY FROM W TO E AS WINDS BACK TO THE SW
AHEAD OF THE NEXT CLIPPER SHORTWAVE TROUGH DIVING SE THROUGH SOUTH
CNTRL CANADA. HOWEVER...A DEVELOPING WAA PATTERN WITH STRONG
285K-295K ISENTROPIC LIFT WILL PROBABLY LEAD TO AN AREA OF -SN
STREAKING SE INTO THE AREA SUN AFTN/NIGHT. HOWEVER...SINCE THE
STRONGER 700-300 MB QVECTOR CONV REMAINS WELL TO THE NORTH WITH THE
TRACK OF THE SHRTWV AND LOWER LEVELS ARE VERY DRY...ONLY CHANCE POPS
WERE INCLUDED FOR SNOWFALL AMOUNTS THAT WOULD AMOUNT TO LESS THAN AN
INCH OVER MOST OF THE CWA.
TUE-THU...THE GFS/GEFS/ECMWF WERE IN REASONABLE AGREEMENT THAT
ANOTHER BATCH OF ARCTIC AIR IS EXPECTED TO MOVE INTO THE NRN GREAT
LAKES IN THE WAKE OF A STRONGER SHORTWAVE MOVING THROUGH NRN ONTARIO
ON TUE. WITH 850 MB TEMPS DROPPING TO AROUND -17C...ANOTHER EXTENDED
PERIOD OF LES WITH AT LEAST MODERATE ACCUMULATIONS IS LIKELY FOR NW
TO N FLOW FAVORED LOCATIONS. THE LES SHOULD DIMINISH BY THU AS THE
SFC HIGH BUILDS INTO THE AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1229 AM EST FRI NOV 22 2013
A NNW FLOW OF VERY COLD AIR ACROSS LAKE SUP WL RESULT IN LES AND
MVFR TO OCNL IFR CONDITIONS EARLY THIS MRNG. BUT AS DRIER AND MORE
STABLE AIR SHOWN ON THE 00Z INL RAOB ARRIVES AFT 08Z...THE LES WL
DIMINISH EVEN AS THE MVFR CIGS PERSIST. AS THE FLOW BACKS MORE TO
THE W AND THEN THE SW WITH THE APRCH AND PASSAGE OF A HI PRES RDG
AXIS LATER THIS MRNG INTO EARLY AFTN...THESE LO CLDS WL GIVE WAY TO
VFR CONDITIONS. MORE MVFR CONDITIONS ARE LIKELY TO REACH THE TAF
SITES W TO E LATER THIS AFTN/EVNG AS A STRONG COLD FNT PASSES. WITH
A MORE ROBUST UPSLOPE WNW WIND COMPONENT...EXPECT MORE LES/IFR WX TO
DVLP AT CMX AND IWD. THE DOWNSLOPE NATURE OF THIS FLOW WL SLOW THE
ARRIVAL OF THESE MORE AUSTERE CONDITIONS AT SAW UNTIL AFT THIS TAF
PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 444 AM EST FRI NOV 22 2013
A FAIRLY ACTIVE NEXT COUPLE DAYS IS IN STORE FOR LAKE SUPERIOR. A
TROUGH THAT MOVED THROUGH LAKE SUPERIOR THIS PAST EVENING WILL
CONTINUE EAST EARLY THIS MORNING...WHILE A HIGH PRESSURE RIDGE
MOVES ACROSS THE LAKE THROUGH EARLY AFTERNOON. THERE WERE A FEW
GALE FORCE GUSTS TO 35KTS SHORTLY AFTER MIDNIGHT...BUT THEY HAVE
SINCE DIMINISHED AND EXPECT A DIMINISHING TREND TO THE WINDS THIS
MORNING. AS THE HIGH PRESSURE RIDGE SHIFTS EAST THIS AFTERNOON
SOUTHWESTERLY WINDS WILL BE ON THE INCREASE OVER WESTERLY LAKE
SUPERIOR AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM. THIS SYSTEM
WILL QUICKLY DIVE SOUTHEAST ACROSS LAKE SUPERIOR LATE THIS AFTERNOON
AND EVENING...QUICKLY SHIFTING WINDS TO THE NORTH-NORTHWEST AND
PRODUCING GALE FORCE WINDS TO 40KTS. THERE COULD EVEN BE SOME GUSTS
TO 45KTS RIGHT AS WINDS SHIFT TO THE NORTH-NORTHWEST AFTER MIDNIGHT
OVER EASTERN LAKE SUPERIOR. THE GALE WARNING THAT IS IN PLACE LOOKS
TO BE IN GOOD SHAPE. A STRONG HIGH DROPPING SOUTH THROUGH THE
NORTHERN PLAINS ON SATURDAY WILL BEGIN TO NOSE A RIDGE OVER WESTERN
LAKE SUPERIOR ON SATURDAY AFTERNOON AND THEN PUSH ACROSS THE ENTIRE
LAKE SATURDAY NIGHT AND SUNDAY. THIS WILL LEAD TO DIMINISHING AND
BACKING WINDS DURING THAT PERIOD. THAT DIMINISHING TREND WILL BE
SHORT LIVED AS WINDS WILL INCREASE ON SUNDAY NIGHT OUT OF THE
SOUTHWEST (TO 30KTS) AHEAD OF LOW MOVING SOUTHEAST THROUGH ONTARIO
LATE SUNDAY NIGHT AND MONDAY. THIS LOW WILL DRAG A COUPLE TROUGHS
ACROSS LAKE SUPERIOR MONDAY AND MONDAY NIGHT...WITH THE SECOND ONE
STALLING OVER SOUTHEAST LAKE SUPERIOR THROUGH WEDNESDAY. AT THIS
POINT...NORTHWEST WINDS UP TO 30KTS ARE EXPECTED BEHIND THE
TROUGHS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 1 AM EST
SUNDAY FOR MIZ004-084.
LAKE EFFECT SNOW WARNING FROM MIDNIGHT TONIGHT TO NOON EST
SUNDAY FOR MIZ006-007-085.
LAKE EFFECT SNOW ADVISORY FROM 5 PM THIS AFTERNOON TO 7 AM EST
SUNDAY FOR MIZ001-003.
LAKE EFFECT SNOW WARNING FROM 6 PM EST /5 PM CST/ THIS EVENING
TO 7 AM EST /6 AM CST/ SUNDAY FOR MIZ002-009.
LAKE EFFECT SNOW ADVISORY FROM 1 AM TO 10 PM EST SATURDAY FOR
MIZ005.
LAKE EFFECT SNOW ADVISORY FROM 1 AM SATURDAY TO 7 AM EST SUNDAY
FOR MIZ014.
LAKE EFFECT SNOW ADVISORY FROM 1 AM SATURDAY TO 5 AM EST SUNDAY
FOR MIZ013.
LAKE SUPERIOR...
GALE WARNING FROM 11 PM THIS EVENING TO 1 AM EST SUNDAY FOR
LSZ266-267.
GALE WARNING FROM 1 AM TO 10 PM EST SATURDAY FOR LSZ248>251-265.
GALE WARNING FROM 10 PM THIS EVENING TO 10 PM EST SATURDAY FOR
LSZ264.
GALE WARNING FROM 10 PM THIS EVENING TO 10 AM EST SATURDAY FOR
LSZ263.
GALE WARNING FROM 10 PM THIS EVENING TO 7 PM EST SATURDAY FOR
LSZ244-245.
GALE WARNING FROM 10 PM THIS EVENING TO 7 AM EST SATURDAY FOR
LSZ242-243.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...JLB
AVIATION...KC
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
445 AM EST FRI NOV 22 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 444 AM EST FRI NOV 22 2013
BROAD AREA OF LIGHT SNOW ASSOCIATED WITH A COUPLED UPPER
JET...SHORTWAVE ENERGY AND MID-LEVEL Q-VECTOR CONVERGENCE CONTINUES
TO SLIDE EAST EARLY THIS MORNING ACROSS UPPER MICHIGAN AND
WISCONSIN. GENERALLY LIGHT SNOW WITH VISIBILITIES IN MOST LOCATIONS
OF 2 TO 5 MILES. WE SAW FINE FLAKES AT OUR OFFICE MOST OF THE
NIGHT...WHICH HAS BEEN HELPFUL IN REDUCING VISIBILITIES. ONE REPORT
FROM NORTHERN WISCONSIN INDICATED A HALF AN INCH OF SNOW
ACCUMULATION AND OUR OFFICE HAD 0.6 INCH AS OF 1AM. THE SNOW HAS
ALREADY ENDED OVER WESTERN UPPER MICHIGAN (KCMX/KIWD OBS) AND
STARTING TO SEE THE REFLECTIVITIES QUICKLY DIMINISH OVER BARAGA
AND IRON COUNTIES. AS THE UPPER LEVEL FEATURES CONTINUE TO SHIFT
EAST THIS MORNING...EXPECT THE SYNOPTIC SNOWFALL TO QUICKLY
DIMINISH THROUGH MID MORNING.
OVER NORTHERN UPPER MICHIGAN...LOW LEVEL 925-850MB NORTH-NORTHWEST
FLOW (ON KMQT VAD AND RAP ANALYSIS) ACROSS LAKE SUPERIOR...ALONG
WITH 850MB TEMPS OF -7C TO -11C FROM EAST TO WEST HAS LED TO SOME
LAKE ENHANCEMENT EARLY THIS MORNING...WITH THE STRONGEST RETURNS ON
RADAR AND OBS INDICATING THE HEAVIEST SNOW OVER EASTERN
MARQUETTE AND WESTERN ALGER COUNTIES. THIS ENHANCEMENT
WILL ALSO BE DIMINISHING QUICKLY THIS MORNING AS A HIGH PRESSURE
RIDGE FROM NORTHERN MINNESOTA NOSES INTO THE AREA. VERY DRY AIR
ABOVE THE INVERSION AT 920MB ON THE 00Z KINL SOUNDING WILL BE WHAT
IS MOVING INTO THE AREA AND REALLY DIMINISH THE INTENSITY OF THE
LAKE ENHANCEMENT OVER THE NORTH CENTRAL THIS MORNING. THIS WILL ALSO
LEAD TO A DIMINISHING TREND TO THE LAKE EFFECT CLOUDS FROM WEST TO
EAST TODAY AS THE LAKE INDUCED INSTABILITY AND MOISTURE IS PINCHED
BY THAT LOWERING INVERSION FROM THE HIGH PRESSURE RIDGE. EXPECT THE
LAKE CLOUDS TO HANG ON THE LONGEST OVER THE KEWEENAW AND THE EAST
WHERE THE BACKING WINDS WINDS WILL STAY FAVORABLE THE LONGEST. THE
REST OF THE AREA SHOULD SEE SKIES BECOMING PARTLY CLOUDY IF NOT
MOSTLY SUNNY LATE THIS MORNING THROUGH THE AFTERNOON.
FOCUS THEN TURNS TO THE MAIN WEATHER MAKER FOR THE FORECAST
PERIOD...WHICH IS ASSOCIATED WITH A LOW THAT IS CURRENTLY LOCATED
NEAR LAKE WINNIPEG. THIS LOW AND POTENT SHORTWAVE NOTED ON WV
IMAGERY WILL QUICKLY SWEEP SOUTHEAST ACROSS LAKE SUPERIOR LATE THIS
AFTERNOON AND EVENING. STRONG CONVERGENCE ALONG TWO ASSOCIATED
TROUGHS WILL LEAD TO A COUPLE MODERATE TO POTENTIALLY HEAVY PERIODS
OF SNOW BEFORE THE LAKE EFFECT REALLY KICKS IN OVERNIGHT.
THE FIRST TROUGH WILL SHIFT WINDS TO THE NORTHWEST AND MOVE INTO THE
KEWEENAW AND WESTERN UPPER MICHIGAN AROUND DINNER TIME AND THE REST
OF THE CWA DURING THE EVENING HOURS. EXPECT THE STRONGEST SNOW TO
OCCUR OVER THE WEST WITH THE FAVORABLE UPSLOPE WINDS AND LEAD TO A
COUPLE HOUR PERIOD OF STRONG SNOW SHOWERS. THEN THERE MAY BE
A SHORT PERIOD OF LIGHTER SNOW AS THE DEEPER MOISTURE CUTS OUT FOR
A FEW HOURS. THE SECONDARY TROUGH (WITH ANOTHER BURST OF
MODERATE TO HEAVY SNOWFALL) WILL THEN DROP SOUTH ACROSS THE KEWEENAW
AND WESTERN UPPER MICHIGAN AROUND OR SHORTLY AFTER
MIDNIGHT...SHIFTING THE WINDS TO ALMOST NORTHERLY AND THE LAKE
EFFECT SNOW SHOULD REALLY KICK IN. EXPECT A SIMILAR OCCURRENCE
ACROSS THE REST OF NORTHERN UPPER MICHIGAN WITH MORE OF A DELAY ON
THE SECONDARY TROUGH UNTIL THE 08-09Z TIME FRAME. IN ADDITION...WITH
THE FIRST FRONT SHIFTING WINDS TO LESS FAVORABLE NORTHWESTERLY
DOWNSLOPING FLOW FOR THE NORTH CENTRAL...THEY WILL LIKELY NOT SEE
MUCH SNOW ACCUMULATION UNTIL THE SECONDARY TROUGH MOVES THROUGH AND
LAKE EFFECT DEVELOPS.
BEHIND THE TROUGHS...850MB TEMPS WILL FALL FROM AROUND -10C AT 18Z
TODAY TO -20C AT 12Z SATURDAY. THIS WILL PROVIDE SIGNIFICANT OVER
THE LAKE INSTABILITY (DELTA-T VALUES APPROACHING 25) AND LEAD TO
LAKE INDUCED CAPE AND EQL LEVELS OF 800 J/KG AND 13-14K
FT RESPECTIVELY. BEST DEEP MOISTURE WILL BE FOCUSED OVER THE EAST
CLOSER TO THE LOW MOVING THROUGH. THUS...EXPECT REALLY GOOD
CONDITIONS FOR MODERATE TO HEAVY LAKE EFFECT SNOW DURING THE
OVERNIGHT HOURS AND CONTINUING INTO SATURDAY. SNOW RATIOS WILL BE
ON THE INCREASE THROUGH THE FORECAST PERIOD...STARTING AROUND
10-15 TO 1 BEFORE INCREASING TO THE LOW 20S ONCE THE LAKE EFFECT
KICKS IN. WITH THE BEST LAKE INDUCED LIFT RIGHT IN THE DGZ...THERE
IS THE POTENTIAL THAT SNOW RATIOS COULD BE HIGHER IN THE STRONGER
BANDS (ESPECIALLY TOWARDS IRONWOOD WHERE THE WINDS ARE LIGHTER) AND
MAY BE SOMETHING TO MONITOR.
AS FOR SNOW AMOUNTS FOR THE WEST FIRST. WHILE THERE WILL BE SOME
BURSTS LATE THIS AFTERNOON AND EVENING...OVERALL AMOUNTS SHOULD BE
IN THE 1-3 INCH RANGE. THEN AS THE LAKE EFFECT KICKS IN
TONIGHT...HAVE ANOTHER 2-4 INCHES OVER THE HIGHER TERRAIN FROM THE
KEWEENAW THROUGH GOGEBIC COUNTIES. THIS PRODUCES TOTALS BY 12Z
SATURDAY OF 3-7 INCHES...WITH THE HIGHEST FOR GOGEBIC/ONTONAGON
DUE TO THE LONGER FETCH AND WEAKER WINDS INCREASING RESIDENCE
TIME OVER THE LAKE. ALSO...IT APPEARS THE INITIAL TROUGH WILL BECOME
HUNG UP IN THAT AREA THIS EVENING...WHICH WOULD ALLOW THE SNOW TO
PERSIST FOR MUCH OF THE EVENING HOURS. MARQUETTE/BARAGA COUNTY AND
LOCATIONS EASTWARD WILL LIKELY NOT REALLY SEE THE SNOW PICKING UP
UNTIL AFTER MIDNIGHT AND LIKELY AROUND 08-09Z WHEN THE TROUGH
FINALLY SHIFTS THROUGH AND SWITCHES THE WINDS MORE NORTH-NORTHWEST.
THIS BECOMES FAIRLY FAVORABLE FOR NORTH CENTRAL AND EASTERN PARTS OF
MARQUETTE COUNTY AND FOCUSED INTO ALGER COUNTY LATE TONIGHT...SO
EXPECT CONDITIONS TO DETERIORATE VERY QUICKLY THERE. WITH AN INCH
AN HOUR SNOW OVER MARQUETTE COUNTY LATE TONIGHT...EXPECT TOTALS IN
THE 2-5 INCH RANGE FROM THE HURON MOUNTAINS THROUGH
NEGAUNEE/SKANDIA BY 12Z. FARTHER EAST...THE DELAYED ARRIVAL WILL
LIKELY KEEP AMOUNTS IN THE 1-3 INCH RANGE.
ALONG WITH THE SNOW...WINDS WILL ALSO INCREASE BEHIND THE
FRONTS...GUSTING TO 40KT GALES OVER CENTRAL AND EASTERN LAKE
SUPERIOR DURING THE OVERNIGHT HOURS. GUSTS TO 35-40MPH WILL BE
COMMON OVER THE KEWEENAW STARTING LATE THIS EVENING AND LATE
TONIGHT EAST OF MARQUETTE. AS THE SNOW STARTS TO
ACCUMULATE...BLOWING SNOW BECOMES A LARGER ISSUE THROUGH THE NIGHT
AND INTO SATURDAY WITH SNOW BEING ON THE GROUND.
AS FOR HEADLINES...COORDINATION WITH THE LONG TERM SHIFT LED TO
SWITCHING GOGEBIC/ONTONAGON AND ALGER/LUCE...NORTHERN SCHOOLCRAFT
TO LAKE EFFECT SNOW WARNINGS DUE TO THEIR FAVORABLE CONDITIONS AND
EXPECTED SNOW ACCUMULATIONS. THERE WAS ENOUGH UNCERTAINTY ON
SNOWFALL AMOUNTS FOR THE KEWEENAW PENINSULA TO OPT FOR AN ADVISORY
AT THIS POINT...SINCE THE LIMITED FETCH (AND UPSLOPE) WITH THE
WINDS WILL KEEP AMOUNTS LOWER. THOSE WINDS COULD ALSO MAKE FOR
WORSE VISIBILITIES AND COULD ALMOST JUSTIFY A WARNING. MARQUETTE
WAS SIMILAR (AND MAY NEED TO BE UPGRADED WITH THE DAY SHIFT)...SINCE
AMOUNTS IN 12 HOURS ARE JUST UNDER WARNING CRITERIA AND THERE IS
SOME UNCERTAINTY ON THE EXACT LOCATION OF THE STRONGER BANDS OFF
LAKE NIPIGON. FINALLY...THE REST OF THE AREAS IN THE WATCH WERE
SWITCHED TO AN ADVISORY.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 405 PM EST THU NOV 21 2013
MAIN FOCUS IN LONG TERM WILL BE THE PASSAGE OF A STRONG ARCTIC COLD
FRONT FRIDAY NIGHT AND POTENTIAL FOR MODERATE TO HEAVY LAKE EFFECT
SNOW ALONG WITH BLOWING SNOW FRI NIGHT THROUGH SAT NIGHT ACROSS THE
NRN AND ERN SECTIONS OF THE CWA. MUCH COLDER TEMPS AND VERY COLD
WIND CHILL VALUES WILL ALSO ACCOMPANY THE FRONTAL PASSAGE.
FRI NIGHT INTO SATURDAY NIGHT...SHORTWAVE ENERGY FROM NW CANADA
DROPS SE LEADING TO UPPER TROF AMPLIFICATION OVER THE GREAT LAKES
THIS WEEKEND. BRIEF PERIOD OF VIGOROUS UPPER FORCING NOTED PER MODEL
DEEP LAYER Q-VECT CONV WILL ENHANCE STRONG OVERWATER INSTABILITY
LEADING TO THE TYPICAL BURST OF MODERATE TO HEAVY LAKE ENHANCED SNOW
OFF LAKE SUPERIOR ALONG THE ASSOCIATED ARCTIC COLD FRONT FRI NIGHT.
THIS BURST OF SNOW COULD ARRIVE AS EARLY AS LATE FRI AFTERNOON OVER
THE KEWEENAW. CONVERGENCE ALONG ARCTIC FRONT SHOULD INCREASE
SUBSTANTIALLY AS THE FRONT CROSSES THE RELATIVELY WARM WATERS OF
LAKE SUPERIOR WITH THE MOST INTENSE BURST OF SNOWFALL ALONG THE
FROPA TO LIKELY IMPACT AREAS EAST OF MARQUETTE. WITH MODEL FCST
850MB TEMPS FALLING TO -17 TO -21C BY 12Z SAT...VIGOROUS NW/NNW FLOW
ORIENTED LAKE EFFECT SNOW BANDS SHOULD QUICKLY ORGANIZE FRI NIGHT
AFTER THE ARCTIC FRONT PASSES. 850MB TEMPS BOTTOM OUT AROUND -21C TO
-22C ACROSS THE AREA SAT. CONSENSUS OF MODEL GUIDANCE IS FOR DEEPER
MOISTURE TO PERSIST LONGER OVER THE ERN FCST AREA WITH BOTH THE GFS
AND NAM SNDGS SHOWING MOISTURE UP TO 700 MB OR AROUND 10KFT THROUGH
12Z SAT. THIS DEEPER MOISTURE COMBINED WITH PRECONDITIONING MOISTURE
OFF LAKE NIPIGON AND A FAVORABLE PLACEMENT OF THE DGZ WITHIN
VIGOROUS UPWARD MOTION ZONE SHOULD LEAD TO A SIGNIFICANT LAKE EFFECT
EVENT FOR ALGER/WRN LUCE/NRN SCHOOLCRAFT. HEAVIEST SNOW FOR THE
EVENT WILL FALL WHERE LES BANDS REALIZE ADDED OVERWATER
FETCH/PRECONDITIONING OFF LAKE NIPIGON. EARLY ON SAT...WINDS ARE
NORTHERLY ENOUGH THAT THE HEAVIEST LES BANDS OR BAND CONNECTED TO
LAKE NIPIGON WILL PROBABLY IMPACT KEWEENAW COUNTY AND MARQUETTE
COUNTY BEFORE WINDS BACK SLIGHTLY FOR THE AFTN. DOMINANT LES BAND
SHOULD THEN SPEND THE REST OF SAT AFTERNOON AND SAT NIGHT IMPACTING
ALGER...SCHOOLCRAFT COUNTIES AND PROBABLY THE NE CORNER OF DELTA
COUNTY.
GUSTY WINDS OF 30-40MPH LATE FRI NIGHT THRU SAT AFTN WILL ALSO LEAD
TO CONSIDERABLE BLOWING AND DRIFTING SNOW AS SNOW ACCUMULATES. OUT
W...SHORTER FETCH...LOWER DGZ AND QUICKER SHALLOWING OF MOISTURE TO
AROUND 6KFT WILL WORK TO LIMIT SNOW ACCUMULATIONS THERE COMPARED TO
THE E. HOWEVER...UPSLOPE TERRAIN ENHANCEMENT AND ENHANCED LOW-LVL
CONVERGENCE COULD STILL LEAD TO SIGNIFICANT TOTAL SNOW ACCUMULATION
OVER PORTIONS OF GOGEBIC/ONTONAGON COUNTIES.
GIVEN SNOW AND BLOWING SNOW POTENTIAL...COMBINED WITH MUCH COLDER
TEMPS AND WIND CHILLS (LOWERING TO -5 TO 5F RANGE) HAVE DECIDED TO
POST WINTER STORM WATCHES ACROSS ALL COUNTIES BORDERING LAKE
SUPERIOR FOR FRI NIGHT INTO SAT NIGHT. WILL ALSO INCLUDE ALL OF
SCHOOLCRAFT COUNTY AS THERE IS A POTENTIAL THAT DOMINANT LES BAND
INITIATING OFF LAKE NIPIGON COULD AFFECT AND EXTEND FAIRLY FAR SOUTH
THROUGH COUNTY GIVEN STRENGTH OF WINDS WITHIN MIXED LAYER. FOR NOW
WILL LEAVE DELTA COUNTY OUT OF WATCH AS THE HEAVIEST SNOW/BLOWING
SNOW WILL AFFECT MAINLY THE NE PORTION OF THE COUNTY...BUT THEY WILL
MOST CERTAINLY NEED AN ADVISORY AT LEAST. TEMPS WILL REMAIN STEADY
OR EVEN FALL SAT AS CORE OF ARCTIC AIR ARRIVES. MOST AREAS WILL STAY
IN THE TEENS SAT.
LES SHOULD MOSTLY END SUNDAY FROM W TO E AS WINDS BACK TO THE SW
AHEAD OF THE NEXT CLIPPER SHORTWAVE DIVING SE THRU SCNTRL CANADA.
HOWEVER...DEVELOPING STRONG WAA PATTERN WILL PROBABLY LEAD TO AN
AREA OF -SN STREAKING SE INTO THE AREA SUN AFTN/NIGHT. IN
FACT...WINDS MAY EVEN BACK ENOUGH FOR LAKE ENHANCED SNOW TO DEVELOP
OFF LAKE MICHIGAN AND IMPACT THE FAR ERN FCST AREA SUN NIGHT. TRACK
OF MAIN SHORTWAVE WILL BE WELL N OF THE FCST AREA SO NOT MUCH OF A
PUSH OF COLD AIR WILL FOLLOW. ANY LES BEHIND THE SYSTEM ON MONDAY
WILL BE MINIMAL.
AS PER PREV FCST...WILL CONTINUE TO LEAN TOWARD THE MORE CONSISTENT
ECMWF FOR TUE/WED...WITH A PAIR OF SHORTWAVES EXPECTED TO REAMPLIFY
THE TROF INTO THE GREAT LAKES. AS WIND SHIFTS TO NW TO N WITH
ASSOCIATED ARCTIC FRONT EXPECT ROUND OF POTENTIALLY SIGNIFICANT LES
OFF LAKE SUPERIOR FOR MON NIGHT INTO WED. LES SHOULD LINGER INTO AT
LEAST THU MORNING AS ECMWF SHOWS CORE OF COLDEST 8H TEMPS (-22C!)
MOVING ACROSS THE REGION BY 12Z THU. RIDGING/SUBSIDENCE FROM WEST
WILL BEGIN TO DIMINISH LES FROM WEST TO EAST THU AFTERNOON.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1229 AM EST FRI NOV 22 2013
A NNW FLOW OF VERY COLD AIR ACROSS LAKE SUP WL RESULT IN LES AND
MVFR TO OCNL IFR CONDITIONS EARLY THIS MRNG. BUT AS DRIER AND MORE
STABLE AIR SHOWN ON THE 00Z INL RAOB ARRIVES AFT 08Z...THE LES WL
DIMINISH EVEN AS THE MVFR CIGS PERSIST. AS THE FLOW BACKS MORE TO
THE W AND THEN THE SW WITH THE APRCH AND PASSAGE OF A HI PRES RDG
AXIS LATER THIS MRNG INTO EARLY AFTN...THESE LO CLDS WL GIVE WAY TO
VFR CONDITIONS. MORE MVFR CONDITIONS ARE LIKELY TO REACH THE TAF
SITES W TO E LATER THIS AFTN/EVNG AS A STRONG COLD FNT PASSES. WITH
A MORE ROBUST UPSLOPE WNW WIND COMPONENT...EXPECT MORE LES/IFR WX TO
DVLP AT CMX AND IWD. THE DOWNSLOPE NATURE OF THIS FLOW WL SLOW THE
ARRIVAL OF THESE MORE AUSTERE CONDITIONS AT SAW UNTIL AFT THIS TAF
PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 444 AM EST FRI NOV 22 2013
A FAIRLY ACTIVE NEXT COUPLE DAYS IS IN STORE FOR LAKE SUPERIOR. A
TROUGH THAT MOVED THROUGH LAKE SUPERIOR THIS PAST EVENING WILL
CONTINUE EAST EARLY THIS MORNING...WHILE A HIGH PRESSURE RIDGE
MOVES ACROSS THE LAKE THROUGH EARLY AFTERNOON. THERE WERE A FEW
GALE FORCE GUSTS TO 35KTS SHORTLY AFTER MIDNIGHT...BUT THEY HAVE
SINCE DIMINISHED AND EXPECT A DIMINISHING TREND TO THE WINDS THIS
MORNING. AS THE HIGH PRESSURE RIDGE SHIFTS EAST THIS AFTERNOON
SOUTHWESTERLY WINDS WILL BE ON THE INCREASE OVER WESTERLY LAKE
SUPERIOR AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM. THIS SYSTEM
WILL QUICKLY DIVE SOUTHEAST ACROSS LAKE SUPERIOR LATE THIS AFTERNOON
AND EVENING...QUICKLY SHIFTING WINDS TO THE NORTH-NORTHWEST AND
PRODUCING GALE FORCE WINDS TO 40KTS. THERE COULD EVEN BE SOME GUSTS
TO 45KTS RIGHT AS WINDS SHIFT TO THE NORTH-NORTHWEST AFTER MIDNIGHT
OVER EASTERN LAKE SUPERIOR. THE GALE WARNING THAT IS IN PLACE LOOKS
TO BE IN GOOD SHAPE. A STRONG HIGH DROPPING SOUTH THROUGH THE
NORTHERN PLAINS ON SATURDAY WILL BEGIN TO NOSE A RIDGE OVER WESTERN
LAKE SUPERIOR ON SATURDAY AFTERNOON AND THEN PUSH ACROSS THE ENTIRE
LAKE SATURDAY NIGHT AND SUNDAY. THIS WILL LEAD TO DIMINISHING AND
BACKING WINDS DURING THAT PERIOD. THAT DIMINISHING TREND WILL BE
SHORT LIVED AS WINDS WILL INCREASE ON SUNDAY NIGHT OUT OF THE
SOUTHWEST (TO 30KTS) AHEAD OF LOW MOVING SOUTHEAST THROUGH ONTARIO
LATE SUNDAY NIGHT AND MONDAY. THIS LOW WILL DRAG A COUPLE TROUGHS
ACROSS LAKE SUPERIOR MONDAY AND MONDAY NIGHT...WITH THE SECOND ONE
STALLING OVER SOUTHEAST LAKE SUPERIOR THROUGH WEDNESDAY. AT THIS
POINT...NORTHWEST WINDS UP TO 30KTS ARE EXPECTED BEHIND THE
TROUGHS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY FROM 5 PM THIS AFTERNOON TO 7 AM EST
SUNDAY FOR MIZ001-003.
LAKE EFFECT SNOW ADVISORY FROM 1 AM SATURDAY TO 5 AM EST SUNDAY
FOR MIZ013.
LAKE EFFECT SNOW ADVISORY FROM 1 AM SATURDAY TO 7 AM EST SUNDAY
FOR MIZ014.
LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 1 AM EST
SUNDAY FOR MIZ004-084.
LAKE EFFECT SNOW WARNING FROM 6 PM EST /5 PM CST/ THIS EVENING
TO 7 AM EST /6 AM CST/ SUNDAY FOR MIZ002-009.
LAKE EFFECT SNOW ADVISORY FROM 1 AM TO 10 PM EST SATURDAY FOR
MIZ005.
LAKE EFFECT SNOW WARNING FROM MIDNIGHT TONIGHT TO NOON EST
SUNDAY FOR MIZ006-007-085.
LAKE SUPERIOR...
GALE WARNING FROM 11 PM THIS EVENING TO 1 AM EST SUNDAY FOR
LSZ266-267.
GALE WARNING FROM 1 AM TO 10 PM EST SATURDAY FOR LSZ265.
GALE WARNING FROM 10 PM THIS EVENING TO 10 PM EST SATURDAY FOR
LSZ264.
GALE WARNING FROM 10 PM THIS EVENING TO 10 AM EST SATURDAY FOR
LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...VOSS
AVIATION...KC
MARINE...SRF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1144 AM CST FRI NOV 22 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 242 AM CST FRI NOV 22 2013
SURFACE ANALYSIS THIS MORNING IS DOMINATED BY HIGH PRESSURE. THERE
ARE TWO HIGH CENTERS OVER CENTRAL NOAM...A 1043 MB HIGH WAS CENTERED
OVER WRN NEB WITH A HIGH OF SIMILAR STRENGTH OVER NRN ALBERTA. IN
BETWEEN THESE TWO HIGHS WAS AN AREA OF LOWER PRESSURE OVER LAKE
WINNIPEG THAT CHECKS IN AT 1028 MB...WHICH UNDER NORMAL
CIRCUMSTANCES WOULD BE THE PRESSURE SEEN AT THE CENTER OF HIGH.
THE NEBRASKA HIGH HAS A RIDGE AXIS THAT STRETCHES NE TO NEAR INL.
WITH THIS AXIS SITTING OVER WEST CENTRAL MN UNDER CLEAR SKIES...HAVE
SEEN SITES OUT BY THE SODAK BORDER DROP TO NEAR ZERO THIS MORNING.
AS FOR THAT CANADIAN HIGH...TEMPERATURES HAVE FOUND THEIR WAY DOWN
TO AROUND -30F ACROSS NRN ALBERTA AND SASKATCHEWAN...WELCOME TO
WINTER.
FOR TODAY...WE WILL SEE BREEZY WSW WINDS DEVELOP OUT AHEAD OF THE
ARCTIC BOUNDARY THAT WILL SLIP INTO THE NW CWA AROUND 18Z...REACH
THE TWIN CITIES AROUND 00Z AND EXIT THE MPX CWA BY 6Z. AS YOU CAN
IMAGINE...WITH SFC PRESSURE VALUES UP NEAR 1030 MB...PRECIP WILL BE
HARD TO COME BY. WITH THAT SAID...IT DOES LOOK LIKE RIGHT BEHIND THE
FRONT THERE WILL BE THE POTENTIAL FOR A QUICK HIT OF LIGHT SNOW.
BOTH THE NAM/GFS SHOW A BAND OF FGEN IN THE H7-H6 LAYER WORKING DOWN
BEHIND THE FRONT. IN ADDITION...FORECAST SOUNDINGS SHOW DEEP
DENDRITIC GROWTH ZONES BECOMING SATURATED AS THE FRONT PASSES...SO
WILL NOT TAKE MUCH LIFT TO GENERATE SOME LIGHT SNOW. HRRR AND
HIRES-NMM REFLECTIVITY FORECASTS INDICATE A LIGHT BAND OF SNOW
DEVELOPING BEHIND THE FRONT AS WELL. FOR NOW...BEEFED UP SKY COVER
THIS EVENING WITH THE FRONT AND WORKED SOME OCCASIONAL FLURRY
WORDING DOWN WITH IT AS WELL.
BEHIND THE FRONT...NAM BUFR SOUNDINGS SHOW THE POTENTIAL FOR NW
WINDS TO BE GUSTING UP AROUND 30 MPH...BUT MORE IMPRESSIVE THAN THAT
IS THE 1050 MB HIGH ALL MODELS SHOW MOVING INTO NODAK LATE TONIGHT.
TO GO ALONG WITH THAT HIGH...BY 12Z SATURDAY...H85 TEMPS WILL
ALREADY BE DOWN IN THE -16 TO -20 C RANGE. 22.00 MODELS ALL CAME IN
A BIT FASTER WITH THE FROPA THIS EVENING AND MOST CAME IN A FEW DEGS
COOLER FOR LOWS SATURDAY MORNING THAN WHAT THEY WERE SHOWING WITH
EARLIER RUNS...SO DID KNOCK A COUPLE OF DEGREES OFF EXISTING LOWS
FOR SATURDAY MORNING. WITH LOWS CURRENTLY FORECAST TO RANGE FROM 2
TO 12...WE WILL BE LAYING A NICE FOUNDATION FOR WHAT WILL BE A
FRIGID SATURDAY.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 242 AM CST FRI NOV 22 2013
THE LONG TERM FORECAST LOOKS COLD AND DRY AS BOTH MN/WI REMAIN
ENTRENCHED IN NORTHWEST FLOW. NORTHERN MN WILL BE CLOSER TO THE
CORE OF COLDEST ARCTIC AIR DROPPING SOUTH OUT OF CANADA
THROUGHOUT THE WEEKEND. AS A RESULT...THE NORTHERN HALF OF THE
STATE HAS A MUCH BETTER CHANCE OF KEEPING CLOUD COVER AND A
CHANCE FOR SNOW FLURRIES AROUND. THE DENDRITE GROWTH ZONE IS NEAR THE
SURFACE WITH AN AIR MASS THIS COLD...SO IF YOU END UP WITH STRATUS
CLOUDS...YOU OFTEN END UP WITH FLURRIES OR LIGHT SNOW. THE
SOUTHERN HALF OF MN AND WEST CENTRAL WI LOOKS A DRIER DOWN LOW
AND SHOULD SEE MORE SUNSHINE. THIS WILL BE OF LITTLE CONSOLATION
AS A BRISK NORTHERLY FLOW BEHIND THE AFOREMENTIONED COLD FRONT
KEEPS TEMPERATURES IN THE TEENS ON SATURDAY WITH WIND CHILLS NEAR
ZERO. THE STRONG COLD ADVECTION WILL CREATE STEEP LAPSE RATES ON
SATURDAY BELOW 900MB AND ENOUGH MIXING TO KEEP GUSTY WINDS UP NEAR
20 MPH. MIXING TO 925MB SHOULD YIELD MID TO UPPER TEENS FOR HIGHS.
BEFORE A SLIGHTLY WARMER WESTERLY FLOW RETURNS ON
SUNDAY...SATURDAY NIGHT WILL BE THE COLDEST NIGHT OF THE FALL
SEASON SO FAR WITH THE ARCTIC HIGH SLIPPING JUST SOUTH OF THE
FORECAST AREA. THE LACK OF SNOW COVER DOESN`T HELP...BUT HARD TO
IMAGINE WE WOULDN`T HAVE MULTIPLE SITES DROP BELOW ZERO.
THERE IS GOOD MODEL AGREEMENT WITH RESPECT TO TEMPERATURES THROUGH
THE EXTENDED. THE DRY PROFILES AND LACK OF CLOUD COVER ACROSS THE
FORECAST AREA OVER THE NEXT 7 DAYS IS HELPING TO KEEP A TIGHTER
ENVELOPE OF MODELED TEMPERATURES /WITHIN 4-7 DEGREES/.
THEREFORE...THERE IS HIGH CONFIDENCE IN BELOW NORMAL TEMPERATURES
OVER THE NEXT 7-10 DAYS. I SUPPOSE YOU COULD ALSO SAY THERE IS
HIGH CONFIDENCE IN BELOW NORMAL PRECIP /NEAR ZERO/ OVER AT LEAST
THE NEXT 7 DAYS AS WELL. THE TIME HEIGHTS OFF THE GFS AND ECMWF
DON`T EVEN CARRY ENOUGH RH TO JUSTIFY MUCH CLOUD COVER...LET ALONE
PRECIP.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1134 AM CST FRI NOV 22 2013
A BAND OF MVFR CIGS/VSBYS DEVELOPED BEHIND A SHARP COLD FRONT
ACROSS NW MN EARLIER TODAY...WHICH WILL AFFECT KAXN BY
1930Z...THEN AT KSTC BY 21-22Z. EVENTUALLY THE MVFR CIGS/VSBYS
WILL ABATE WITH ONLY FLURRIES POSSIBLE AS MOST OF THE MOISTURE
WILL BE LIMITED AFT 23Z. SOME GUSTY WINDS HAVE DEVELOPED AHEAD OF
THIS FRONT SO DECIDED TO ADD GUSTY WINDS DURING THE AFTN ARND
16-18 KTS. MOST OF THE STRONGER GUSTY WINDS OCCUR BEHIND THE FRONT
LATER THIS EVENING...BEFORE DECREASING SATURDAY AFTN.
KMSP...
VFR CONDS SHOULD PREVAIL THRU THE TAF PERIOD WITH ONLY A SMALL
WINDOW OF MVFR VSBY IN -SN ARND 00-02Z AS A SHARP COLD FRONT MOVES
THROUGH. SOME GUSTY WINDS WILL OCCUR AHEAD OF THIS FRONT...BUT
MOST OF THE STRONGER GUSTS WILL BE BEHIND THE FRONT LATER THIS
EVENING AND OVERNIGHT...BEFORE DECREASING SATURDAY AFTN.
/OUTLOOK FOR KMSP/
SUN...VFR. WINDS LIGHT AND VRB IN MRNG...BCMG S AT 15G25KTS.
MON...VFR. WINDS WNW AT 10KTS.
TUE...VFR. WINDS NNW 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...CLF
AVIATION...JLT
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
538 AM CST FRI NOV 22 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 242 AM CST FRI NOV 22 2013
SURFACE ANALYSIS THIS MORNING IS DOMINATED BY HIGH PRESSURE. THERE
ARE TWO HIGH CENTERS OVER CENTRAL NOAM...A 1043 MB HIGH WAS CENTERED
OVER WRN NEB WITH A HIGH OF SIMILAR STRENGTH OVER NRN ALBERTA. IN
BETWEEN THESE TWO HIGHS WAS AN AREA OF LOWER PRESSURE OVER LAKE
WINNIPEG THAT CHECKS IN AT 1028 MB...WHICH UNDER NORMAL
CIRCUMSTANCES WOULD BE THE PRESSURE SEEN AT THE CENTER OF HIGH.
THE NEBRASKA HIGH HAS A RIDGE AXIS THAT STRETCHES NE TO NEAR INL.
WITH THIS AXIS SITTING OVER WEST CENTRAL MN UNDER CLEAR SKIES...HAVE
SEEN SITES OUT BY THE SODAK BORDER DROP TO NEAR ZERO THIS MORNING.
AS FOR THAT CANADIAN HIGH...TEMPERATURES HAVE FOUND THEIR WAY DOWN
TO AROUND -30F ACROSS NRN ALBERTA AND SASKATCHEWAN...WELCOME TO
WINTER.
FOR TODAY...WE WILL SEE BREEZY WSW WINDS DEVELOP OUT AHEAD OF THE
ARCTIC BOUNDARY THAT WILL SLIP INTO THE NW CWA AROUND 18Z...REACH
THE TWIN CITIES AROUND 00Z AND EXIT THE MPX CWA BY 6Z. AS YOU CAN
IMAGINE...WITH SFC PRESSURE VALUES UP NEAR 1030 MB...PRECIP WILL BE
HARD TO COME BY. WITH THAT SAID...IT DOES LOOK LIKE RIGHT BEHIND THE
FRONT THERE WILL BE THE POTENTIAL FOR A QUICK HIT OF LIGHT SNOW.
BOTH THE NAM/GFS SHOW A BAND OF FGEN IN THE H7-H6 LAYER WORKING DOWN
BEHIND THE FRONT. IN ADDITION...FORECAST SOUNDINGS SHOW DEEP
DENDRITIC GROWTH ZONES BECOMING SATURATED AS THE FRONT PASSES...SO
WILL NOT TAKE MUCH LIFT TO GENERATE SOME LIGHT SNOW. HRRR AND
HIRES-NMM REFLECTIVITY FORECASTS INDICATE A LIGHT BAND OF SNOW
DEVELOPING BEHIND THE FRONT AS WELL. FOR NOW...BEEFED UP SKY COVER
THIS EVENING WITH THE FRONT AND WORKED SOME OCCASIONAL FLURRY
WORDING DOWN WITH IT AS WELL.
BEHIND THE FRONT...NAM BUFR SOUNDINGS SHOW THE POTENTIAL FOR NW
WINDS TO BE GUSTING UP AROUND 30 MPH...BUT MORE IMPRESSIVE THAN THAT
IS THE 1050 MB HIGH ALL MODELS SHOW MOVING INTO NODAK LATE TONIGHT.
TO GO ALONG WITH THAT HIGH...BY 12Z SATURDAY...H85 TEMPS WILL
ALREADY BE DOWN IN THE -16 TO -20 C RANGE. 22.00 MODELS ALL CAME IN
A BIT FASTER WITH THE FROPA THIS EVENING AND MOST CAME IN A FEW DEGS
COOLER FOR LOWS SATURDAY MORNING THAN WHAT THEY WERE SHOWING WITH
EARLIER RUNS...SO DID KNOCK A COUPLE OF DEGREES OFF EXISTING LOWS
FOR SATURDAY MORNING. WITH LOWS CURRENTLY FORECAST TO RANGE FROM 2
TO 12...WE WILL BE LAYING A NICE FOUNDATION FOR WHAT WILL BE A
FRIGID SATURDAY.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 242 AM CST FRI NOV 22 2013
THE LONG TERM FORECAST LOOKS COLD AND DRY AS BOTH MN/WI REMAIN
ENTRENCHED IN NORTHWEST FLOW. NORTHERN MN WILL BE CLOSER TO THE
CORE OF COLDEST ARCTIC AIR DROPPING SOUTH OUT OF CANADA
THROUGHOUT THE WEEKEND. AS A RESULT...THE NORTHERN HALF OF THE
STATE HAS A MUCH BETTER CHANCE OF KEEPING CLOUD COVER AND A
CHANCE FOR SNOW FLURRIES AROUND. THE DENDRITE GROWTH ZONE IS NEAR THE
SURFACE WITH AN AIR MASS THIS COLD...SO IF YOU END UP WITH STRATUS
CLOUDS...YOU OFTEN END UP WITH FLURRIES OR LIGHT SNOW. THE
SOUTHERN HALF OF MN AND WEST CENTRAL WI LOOKS A DRIER DOWN LOW
AND SHOULD SEE MORE SUNSHINE. THIS WILL BE OF LITTLE CONSOLATION
AS A BRISK NORTHERLY FLOW BEHIND THE AFOREMENTIONED COLD FRONT
KEEPS TEMPERATURES IN THE TEENS ON SATURDAY WITH WIND CHILLS NEAR
ZERO. THE STRONG COLD ADVECTION WILL CREATE STEEP LAPSE RATES ON
SATURDAY BELOW 900MB AND ENOUGH MIXING TO KEEP GUSTY WINDS UP NEAR
20 MPH. MIXING TO 925MB SHOULD YIELD MID TO UPPER TEENS FOR HIGHS.
BEFORE A SLIGHTLY WARMER WESTERLY FLOW RETURNS ON
SUNDAY...SATURDAY NIGHT WILL BE THE COLDEST NIGHT OF THE FALL
SEASON SO FAR WITH THE ARCTIC HIGH SLIPPING JUST SOUTH OF THE
FORECAST AREA. THE LACK OF SNOW COVER DOESN`T HELP...BUT HARD TO
IMAGINE WE WOULDN`T HAVE MULTIPLE SITES DROP BELOW ZERO.
THERE IS GOOD MODEL AGREEMENT WITH RESPECT TO TEMPERATURES THROUGH
THE EXTENDED. THE DRY PROFILES AND LACK OF CLOUD COVER ACROSS THE
FORECAST AREA OVER THE NEXT 7 DAYS IS HELPING TO KEEP A TIGHTER
ENVELOPE OF MODELED TEMPERATURES /WITHIN 4-7 DEGREES/.
THEREFORE...THERE IS HIGH CONFIDENCE IN BELOW NORMAL TEMPERATURES
OVER THE NEXT 7-10 DAYS. I SUPPOSE YOU COULD ALSO SAY THERE IS
HIGH CONFIDENCE IN BELOW NORMAL PRECIP /NEAR ZERO/ OVER AT LEAST
THE NEXT 7 DAYS AS WELL. THE TIME HEIGHTS OFF THE GFS AND ECMWF
DON`T EVEN CARRY ENOUGH RH TO JUSTIFY MUCH CLOUD COVER...LET ALONE
PRECIP.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 523 AM CST FRI NOV 22 2013
ANOTHER ARCTIC BOUNDARY SLIPPING ACROSS NODAK THIS MORNING WILL
PROVIDE THE ONLY EXCITEMENT THIS TAF PERIOD. ALREADY SEEING WINDS
BACK TO THE SW OUT AHEAD OF THE FRONT OVER NW MN AND THIS TREND
WILL CONTINUE DOWN INTO THE MPX TERMINALS THIS MORNING AS THE
FRONT APPROACHES. MODEL TIMING OF THE FROPA HAS NOT CHANGED MUCH
SO CONFIDENCE REMAINS HIGH IN ITS TIMING. MIXING PROFILES SUPPORT
SOME GUSTS INTO THE MID 20S BEHIND THE FRONT SAT NIGHT. IN
ADDITION...HRRR REFLECTIVITY FORECAST CONTINUES TO SHOW A BAND OF
LIGHT SNOW AND LOWER CIGS WORKING SOUTH JUST BEHIND THE FRONT.
THIS WILL NOT BE ALL THAT IMPRESSIVE...BUT SHOULD PROVIDE AN HOUR
OR TWO OF LIGHT SNOW...ESPECIALLY FOR CENTRAL MN. HAVE CONTINUED
WITH THE TEMPO -SN GROUPS AT TERMINALS AS A RESULT.
KMSP...WITH WINDS UP AROUND FARGO COMING OUT AT 190
DIRECTION...WILL HAVE TO WATCH DIRECTION CLOSELY BETWEEN 17Z AND
21Z AS THE COULD BACK FAR ENOUGH SOUTH TO LEAD TO THE POSSIBILITY
OF HAVING TO BRIEFLY SWAP OUT OF THE 30S. AS FOR SNOW...NOT
EXPECTING MUCH...BUT ENOUGH OF A POSSIBILITY EXISTS TO KEEP THE
TEMPO GROUP GOING.
/OUTLOOK FOR KMSP/
SAT...VFR. WINDS NNW AT 10G15KTS.
SUN...VFR. WINDS LIGHT AND VRB IN MRNG...BCMG S AT 15G25KTS.
MON...VFR. WINDS WNW AT 10KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...CLF
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
416 AM CST FRI NOV 22 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 242 AM CST FRI NOV 22 2013
SURFACE ANALYSIS THIS MORNING IS DOMINATED BY HIGH PRESSURE. THERE
ARE TWO HIGH CENTERS OVER CENTRAL NOAM...A 1043 MB HIGH WAS CENTERED
OVER WRN NEB WITH A HIGH OF SIMILAR STRENGTH OVER NRN ALBERTA. IN
BETWEEN THESE TWO HIGHS WAS AN AREA OF LOWER PRESSURE OVER LAKE
WINNIPEG THAT CHECKS IN AT 1028 MB...WHICH UNDER NORMAL
CIRCUMSTANCES WOULD BE THE PRESSURE SEEN AT THE CENTER OF HIGH.
THE NEBRASKA HIGH HAS A RIDGE AXIS THAT STRETCHES NE TO NEAR INL.
WITH THIS AXIS SITTING OVER WEST CENTRAL MN UNDER CLEAR SKIES...HAVE
SEEN SITES OUT BY THE SODAK BORDER DROP TO NEAR ZERO THIS MORNING.
AS FOR THAT CANADIAN HIGH...TEMPERATURES HAVE FOUND THEIR WAY DOWN
TO AROUND -30F ACROSS NRN ALBERTA AND SASKATCHEWAN...WELCOME TO
WINTER.
FOR TODAY...WE WILL SEE BREEZY WSW WINDS DEVELOP OUT AHEAD OF THE
ARCTIC BOUNDARY THAT WILL SLIP INTO THE NW CWA AROUND 18Z...REACH
THE TWIN CITIES AROUND 00Z AND EXIT THE MPX CWA BY 6Z. AS YOU CAN
IMAGINE...WITH SFC PRESSURE VALUES UP NEAR 1030 MB...PRECIP WILL BE
HARD TO COME BY. WITH THAT SAID...IT DOES LOOK LIKE RIGHT BEHIND THE
FRONT THERE WILL BE THE POTENTIAL FOR A QUICK HIT OF LIGHT SNOW.
BOTH THE NAM/GFS SHOW A BAND OF FGEN IN THE H7-H6 LAYER WORKING DOWN
BEHIND THE FRONT. IN ADDITION...FORECAST SOUNDINGS SHOW DEEP
DENDRITIC GROWTH ZONES BECOMING SATURATED AS THE FRONT PASSES...SO
WILL NOT TAKE MUCH LIFT TO GENERATE SOME LIGHT SNOW. HRRR AND
HIRES-NMM REFLECTIVITY FORECASTS INDICATE A LIGHT BAND OF SNOW
DEVELOPING BEHIND THE FRONT AS WELL. FOR NOW...BEEFED UP SKY COVER
THIS EVENING WITH THE FRONT AND WORKED SOME OCCASIONAL FLURRY
WORDING DOWN WITH IT AS WELL.
BEHIND THE FRONT...NAM BUFR SOUNDINGS SHOW THE POTENTIAL FOR NW
WINDS TO BE GUSTING UP AROUND 30 MPH...BUT MORE IMPRESSIVE THAN THAT
IS THE 1050 MB HIGH ALL MODELS SHOW MOVING INTO NODAK LATE TONIGHT.
TO GO ALONG WITH THAT HIGH...BY 12Z SATURDAY...H85 TEMPS WILL
ALREADY BE DOWN IN THE -16 TO -20 C RANGE. 22.00 MODELS ALL CAME IN
A BIT FASTER WITH THE FROPA THIS EVENING AND MOST CAME IN A FEW DEGS
COOLER FOR LOWS SATURDAY MORNING THAN WHAT THEY WERE SHOWING WITH
EARLIER RUNS...SO DID KNOCK A COUPLE OF DEGREES OFF EXISTING LOWS
FOR SATURDAY MORNING. WITH LOWS CURRENTLY FORECAST TO RANGE FROM 2
TO 12...WE WILL BE LAYING A NICE FOUNDATION FOR WHAT WILL BE A
FRIGID SATURDAY.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 242 AM CST FRI NOV 22 2013
THE LONG TERM FORECAST LOOKS COLD AND DRY AS BOTH MN/WI REMAIN
ENTRENCHED IN NORTHWEST FLOW. NORTHERN MN WILL BE CLOSER TO THE
CORE OF COLDEST ARCTIC AIR DROPPING SOUTH OUT OF CANADA
THROUGHOUT THE WEEKEND. AS A RESULT...THE NORTHERN HALF OF THE
STATE HAS A MUCH BETTER CHANCE OF KEEPING CLOUD COVER AND A
CHANCE FOR SNOW FLURRIES AROUND. THE DENDRITE GROWTH ZONE IS NEAR THE
SURFACE WITH AN AIR MASS THIS COLD...SO IF YOU END UP WITH STRATUS
CLOUDS...YOU OFTEN END UP WITH FLURRIES OR LIGHT SNOW. THE
SOUTHERN HALF OF MN AND WEST CENTRAL WI LOOKS A DRIER DOWN LOW
AND SHOULD SEE MORE SUNSHINE. THIS WILL BE OF LITTLE CONSOLATION
AS A BRISK NORTHERLY FLOW BEHIND THE AFOREMENTIONED COLD FRONT
KEEPS TEMPERATURES IN THE TEENS ON SATURDAY WITH WIND CHILLS NEAR
ZERO. THE STRONG COLD ADVECTION WILL CREATE STEEP LAPSE RATES ON
SATURDAY BELOW 900MB AND ENOUGH MIXING TO KEEP GUSTY WINDS UP NEAR
20 MPH. MIXING TO 925MB SHOULD YIELD MID TO UPPER TEENS FOR HIGHS.
BEFORE A SLIGHTLY WARMER WESTERLY FLOW RETURNS ON
SUNDAY...SATURDAY NIGHT WILL BE THE COLDEST NIGHT OF THE FALL
SEASON SO FAR WITH THE ARCTIC HIGH SLIPPING JUST SOUTH OF THE
FORECAST AREA. THE LACK OF SNOW COVER DOESN`T HELP...BUT HARD TO
IMAGINE WE WOULDN`T HAVE MULTIPLE SITES DROP BELOW ZERO.
THERE IS GOOD MODEL AGREEMENT WITH RESPECT TO TEMPERATURES THROUGH
THE EXTENDED. THE DRY PROFILES AND LACK OF CLOUD COVER ACROSS THE
FORECAST AREA OVER THE NEXT 7 DAYS IS HELPING TO KEEP A TIGHTER
ENVELOPE OF MODELED TEMPERATURES /WITHIN 4-7 DEGREES/.
THEREFORE...THERE IS HIGH CONFIDENCE IN BELOW NORMAL TEMPERATURES
OVER THE NEXT 7-10 DAYS. I SUPPOSE YOU COULD ALSO SAY THERE IS
HIGH CONFIDENCE IN BELOW NORMAL PRECIP /NEAR ZERO/ OVER AT LEAST
THE NEXT 7 DAYS AS WELL. THE TIME HEIGHTS OFF THE GFS AND ECMWF
DON`T EVEN CARRY ENOUGH RH TO JUSTIFY MUCH CLOUD COVER...LET ALONE
PRECIP.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1150 PM CST THU NOV 21 2013
BAND OF SNOW CONTINUES ACROSS FAR SOUTHERN MN AND INTO WESTERN
WISCONSIN AT TAF ISSUANCE TIME. THIS BAND WILL SHIFT SOUTHEAST
DURING THE NEXT FEW HOURS AS DRIER AIR FEEDS IN. CIGS WILL
CONTINUE TO IMPROVE OVERNIGHT WITH CLEAR SKIES EXPECTED BY EARLY
FRIDAY MORNING. ANOTHER ARCTIC COLD FRONT WILL PUSH THROUGH LATE
FRIDAY... AND MODELS INDICATE SOME CHANCE OF SNOW SHOWERS WITH THE
FROPA AS TEMPERATURES DROP INTO THE OPTIMAL RANGE FOR SNOWFLAKE
FORMATION IN A HIGH RH PROFILE. WINDY NORTHWEST WINDS AND DRIER
AIR WILL QUICKLY FOLLOW FRIDAY NIGHT.
KMSP...VFR CONDITIONS UNTIL LATE FRIDAY WHEN A BAND OF MVFR CIGS
AND SNOW SHOWERS MAY ACCOMPANY AN ARCTIC COLD FRONT.
/OUTLOOK FOR KMSP/
SAT...VFR. WINDS NNW AT 10G15KTS.
SUN...VFR. WINDS LIGHT AND VRB...BECOMING S AT 10G15KTS LATE.
MON...VFR. WINDS NW AT 15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...CLF
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1152 PM CST THU NOV 21 2013
.UPDATE...
ISSUED AT 1002 PM CST THU NOV 21 2013
PREVIOUS FORECAST HAD POPS THROUGH TOMORROW MORNING...WITH
MORNING POPS MAINLY ACROSS OUR KANSAS COUNTIES. SOUNDINGS ARE
INDICATING A DRIER ATMOSPHERE THAN PREVIOUSLY FORECAST. RADAR
TRENDS ARE ALSO INDICATING DECREASING COVERAGE ACROSS THE AREA.
00Z NAM SHOWS DRY CONDITIONS. FURTHERMORE...THE HRRR IS PAINTING
DRY CONDITIONS ACROSS THE FORECAST AREA. CONSEQUENTLY...DECREASED
POPS ACROSS THE OUTLOOK AREA FOR THE REST OF THIS EVENING AND INTO
TOMORROW MORNING. BASICALLY A DRY FORECAST THROUGH TOMORROW.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 549 PM CST THU NOV 21 2013
TONIGHT AND FRIDAY. MAIN CONCERNS CONTINUE TO BE THE CURRENT
WINTER WEATHER SYSTEM AND WHEN SNOW WILL COME TO AN END.
LATEST RADAR TRENDS HAVE THE HEAVIER PRECIPITATION RETURNS ACROSS
THE FAR SOUTHEAST PART OF THE FORECAST AREA...AND EVEN THESE ARE
DIMINISHING SOME EARLY THIS AFTERNOON. THESE ARE PRIMARILY LIGHT
FREEZING RAIN OR SLEET. IN THE WEST THERE ARE SOME LIGHTER RETURNS
AND OBSERVATIONS AND WEB CAMS INDICATE THAT THIS IS SOME LIGHT SNOW.
MODELS CONTINUE TO BRING IN ANOTHER WEAK UPPER LEVEL DURING THE
EVENING AND THE SNOW ACROSS WESTERN NEBRASKA WILL CONTINUE TO MOVE
TO THE EAST AND INTO THE FORECAST AREA DURING THE LATE AFTERNOON AND
EVENING. HAVE MAINTAINED THE HIGH POPS ACROSS THE AREA THROUGH THE
AFTERNOON AND THEN SLOWLY DIMINISHED THE CHANCES DURING THE EVENING
AND ESPECIALLY OVERNIGHT. THE MAIN QUESTION IS WHAT TYPE OF
PRECIPITATION WILL HAPPEN IN THE SOUTHEAST. THE LATEST MODEL
GUIDANCE HAS A WARM LAYER THAT FINALLY COOLS ENOUGH TO PRODUCE A
SLEET/SNOW MIXTURE BY MID AFTERNOON AND SHOULD BE ALL SNOW BY
EVENING. WILL CONTINUE THE ADVISORY.
THE SNOW WILL GRADUALLY COME TO AN END FROM WEST TO EAST LATE
TONIGHT. THE ONLY EXCEPTION TO THIS WILL BE ACROSS KANSAS. THERE IS
A WEAK UPPER LEVEL WAVE THAT WILL MOVE INTO THE AREA FRIDAY MORNING.
THERE IS A BAND OF SNOW THAT IS EXPECTED TO DEVELOP IN THE VICINITY
OF INTERSTATE 70. THE MODELS INDICATE THAT MOST OF THE SNOW SHOULD
BE TO THE SOUTH OF THE FORECAST AREA SO HAVE KEPT SOME LOW POPS
MAINLY ACROSS THE FAR SOUTH.
CLOUDS SHOULD DIMINISH SLOWLY ACROSS THE AREA ON FRIDAY...ALTHOUGH
PARTLY TO MOSTLY CLOUDY SKIES ARE EXPECTED IN THE SOUTHERN PART OF
THE AREA.
COLD AIR WILL CONTINUE TO PUSH INTO THE AREA TONIGHT WITH LOWS IN
THE TEENS. THE COLD AIR WILL CONTINUE ACROSS THE AREA ON FRIDAY WITH
HIGHS IN THE LOWER 30S.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 549 PM CST THU NOV 21 2013
THE OVERALL TREND FOR THE SATURDAY THROUGH THANKSGIVING DAY
TIME FRAME IS COOLER THAN NORMAL TEMPERATURES...AND GENERALLY DRY
CONDITIONS. WE WILL BREAK IT DOWN INTO TWO TIME FRAMES.
SATURDAY-MONDAY...SATURDAY IS FLAT OUT COLD. SECONDARY PUSH OF COLD AIR
OVERNIGHT FRIDAY NIGHT WILL INCREASE WINDS FOR THE FIRST HALF OF THE
DAY SATURDAY AND WILL PUSH WIND CHILLS AT OR BELOW ZERO THROUGH
MIDDAY SATURDAY. BOTH THE NAM/GFS HINT AT SOME BROKEN LOW STRATUS
BEHIND THE FRONT OVER/NEAR THE NORTHERN PART OF THE AREA. WINDS WILL
DROP OFF QUICKLY DROP THANKFULLY BY LATE AFTERNOON...BUT TEMPERATURES
WILL BE 15-20 DEGREES BELOW NORMAL. ON SUNDAY...A RETURN SOUTHERLY
FLOW WILL PUSH TEMPERATURES UP BACK INTO THE 30S...BUT THOSE SOUTH
WINDS WILL BE CHILLING A LOT LIKELY SATURDAY. ANOTHER COLD ONE. THERE
ARE MODEL HINTS/IDEAS OF A CUT OFF SOUTHWEST U.S. LOW PRESSURE TRYING
TO MEANDER INTO THE SOUTHERN PLAINS SUNDAY/MONDAY TIME FRAME. THERE
ARE DIFFERENCES IN LOCATION/TIMING. BELIEVE WE WILL SEE CLOUDS
INCREASE SUNDAY...BUT MODELS TEND TO BRING PRECIPITATION TOO FAR
NORTH INTO COLD AIR MASSES SUCH AS THIS. COMFORTABLE WITH NO CHANCE
OF MEASURABLE PRECIPITATION AT THIS POINT...WITH UPCOMING FORECAST
CREWS NEEDING TO KEEP AN EYE ON THE SYSTEM AND ITS MOVEMENT CLOSELY.
TUESDAY-THANKSGIVING DAY...OVERALL THE CENTRAL PLAINS WILL BE COOLER
THAN NORMAL...THANKS SHARING IN CHILLY...CYCLONIC FLOW AROUND HUDSON
BAY VORTEX. THERE IS NO INDICATION AT THIS JUNCTURE OF ANY MAJOR
WEATHER SYSTEM IMPACTING THANKSGIVING DAY...THE WEDNESDAY BEFORE OR
BLACK FRIDAY REALLY. LOOK FOR LOTS OF HIGHS IN THE 30S AN AND
OCCASIONAL LOWER 40 DEGREE DAY NEXT WEEK. THIS COOLISH WEATHER
PATTERN WILL TAKE US RIGHT INTO DECEMBER...AS THE REGION GENERALLY
REMAINS INFLUENCED BY A COLDER WEST/NORTHWEST FLOW AND OCCASIONAL
COLD AIR INTRUSIONS FROM THE CANADIAN PROVINCES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1138 PM CST THU NOV 21 2013
CONDITIONS WILL CONTINUE TO GRADUALLY IMPROVE OVERNIGHT WITH VFR
CONDITIONS EXPECTED. MID-LEVEL CEILINGS SHOULD LIFT TO HIGHER
LEVELS AS THE WEATHER SYSTEM GIVING US SOME LIGHT SNOW CONTINUES
TO MOVE EAST.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...GUERRERO
SHORT TERM...JCB
LONG TERM...MORITZ
AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
232 AM EST FRI NOV 22 2013
.SYNOPSIS...
WIDELY SCATTERED SHOWERS THIS MORNING WILL TAPPER OFF BY EARLY
AFTERNOON IN ADVANCE OF A COLD FRONT THAT WILL MOVE THROUGH THE
AREA LATER THIS EVENING. AS THIS FRONT CROSS THE AREA...EXPECT
SHOWERS TO REDEVELOP WITH RAINFALL THEN COMING TO AN END SHORTLY
AFTER MIDNIGHT. MOSTLY DRY CONDITIONS ON SATURDAY WILL QUICKLY
GIVE WAY TO DEVELOPING SNOW SHOWERS BY AFTERNOON AND EVENING AS A
STRONG ARCTIC COLD FRONT MOVES THROUGH THE AREA. AS THE COLDEST
AIRMASS OF THE SEASON DESCENDS UPON THE REGION...EXPECT DEVELOPING
LAKE EFFECT SNOWS SOUTHEAST OF LAKE ONTARIO. SNOW WILL INCREASE IN
INTENSITY SATURDAY NIGHT WITH HEAVY ACCUMULATIONS POSSIBLE FOR
PORTIONS OF CENTRAL NEW YORK.
&&
.NEAR TERM /THROUGH TONIGHT/...
1 AM UPDATE...
RAIN SHOWERS CONTINUING TO DEVELOP ACROSS THE REGION EARLY THIS
MORNING AS WARM AIR ADVECTION IN ADVANCE OF AN APPROACHING WARM
FRONT COMBINED WITH THE PASSAGE OF A WEAK SHORTWAVE IN WEST
SOUTHWEST FLOW ALOFT. HAVE INCREASED POPS BASED ON LATEST RADAR
TRENDS AND EXPECTATIONS FOR FURTHER MOVEMENT LATER THIS MORNING.
TEMPS/DEWPOINTS LOOK GOOD...NO REAL ADJUSTMENTS NEEDED AT THIS
TIME.
900 PM UPDATE...UPDATED TO SPEED UP THE ARRIVAL OF THE SHRA ACRS
SRN NY AND NE PA. LATEST HRRR MODEL REFLECTIVITY WAS A TRACK AND
UPDATED HOURLY POPS USING MODEL-RADAR SMART TOOL THRU 9Z. THE HRRR
SHOWS A WIDESPREAD AREA OF LIGHT SHRA SPREADING W-E INTO THE
OVERNIGHT. TEMPERATURES ACRS THE ENTIRE FORECAST AREA WERE ABV
FREEZING. UPPER MOHAWK VALLEY WILL NOT SEE ANY SIGNIFICANT MIXED
PRECIP AS PER LATEST RAP...NAM AND GFS MODEL SOUNDINGS AND ALSO
BNDRY LAYER TEMPS WHICH WERE ARND 40F. LATEST LAPS WET BULB TEMPS
WERE IN THE MID TO UPPER 30S IN ONEIDA CO SO THIS COMBINED WITH
LOW- LEVEL WAA SHUD PRECLUDE ANY CHANCE FOR FZRA AS PRECIP CONTS
TO WORK INTO THESE AREAS. SMALL CHC FOR A LITTLE IP BUT IT WON/T
BE SIGNIFICANT ENUF TO WARRANT MENTION IN GRIDS OR ANY PRODUCTS.
TWEAKED REST OF SHORT TERM GRIDS JUST A LITTLE. PREVIOUS DSCN IS
BELOW FROM 700 PM UPDATE..
700 PM UPDATE...AREA RADARS SHOWG SHRA SPREADING INTO WRN AND
CNTRL NY AND NW PA/NC PA AT THIS TIME. THESE SHRA WERE ASSCTD WITH
AN ACCELERATING SWRLY LOW-LEVEL JET ARND 850 MB WHICH WAS RISING
ISENTROPICALLY INTO NY AND NRN PA THIS EVE. THIS LL JET WAS TIED
TO AN UPPER LEVEL JET STREAK AND ASSCTD UPR WAVE WHICH WAS
PROPAGATING INTO THE GREAT LAKES AND UPR OH VLLY. THIS SHOT OF
ISEN LIFT/WAA WILL SHOOT THRU THE REGION BETWEEN 00Z AND 12Z FRI.
FOLLOWED LATEST HRRR FOR TIMING OF HOURLY POPS IN GRIDS TONIGHT AS
THIS MODEL SEEMS TO HAVE THE BEST HANDLE ON THE PRESENTLY EVOLVING
SHRA.
AFTER THIS FIRST UPR LVL WAVE AND ASSCTD LLJ PASSES E AND
WEAKENS BY 12Z...THERE WILL BE A LULL IN THE PRECIP FOR MUCH OF
FRI. I CAN SEE ISLD TO SCT SHRA ACVTY AT BEST AS WE WAIT FOR THE
NEXT LARGER SCALE UPR LVL WAVE TO MAKE A PUSH TO THE E INTO THE UPR
LAKES AND ONT BY 21Z FRI TO 00Z SAT. THIS WILL BE THE IMPETUS TO
PUSH THE SFC CD FRNT INTO WRN AND CNTRL NY LATE FRIDAY PM. HAVE
TRENDED POPS DOWNWARD FRI AM AND BRING THEM BACK UP BY LATE FRI AS
RESULT TO ACCOUNT FOR THIS LULL IN ACVTY. I MAY FURTHER REFINE THIS
WITH NEXT UPDATE AS WELL.
AS FOR PRECIP TYPE...I SEE ALL RAIN TONIGHT THRU FRI. MODEL
SOUNDING DATA IS QUITE WARM EVEN IN OUR COLDEST LOCATIONS IN THE
UPPER MOHAWK VALLEY AND CATSKILLS WHERE LL TEMPS ARE WELL ABV
FREEZING AT THE ONSET OF THIS EVE/S PRECIP. THE COLDER AIR DOES NOT
ARRIVE UNTIL FRI NGT TO TURN PRECIP TO SNOW BEFORE IT ENDS. SO
JUST PLAIN RAIN ALL DAY FRI.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
330 PM EST UPDATE...
THE CHANCE FOR RAIN SHOWERS WILL INCREASE EARLY FRIDAY MORNING
FROM WEST TO EAST AS THE ATMOSPHERIC COLUMN BECOMES SATURATED AND
STRONG ISENTROPIC LIFT REMAINS OVER NY/PA. THE BEST CHANCE FOR
RAIN SHOWERS FRIDAY MORNING WILL BE OVER THE WESTERN PORTIONS OF
THE CWA WHERE THE GREATEST UPPER LEVEL SUPPORT IS LOCATED. FRIDAY
AFTERNOON THERE WILL BE A BRIEF DECREASE IN ACTIVITY AHEAD OF AN
ADVANCING STRONG COLD FRONT/SFC TROUGH. THE COLD FRONT IS
EXPECTED TO PUSH INTO THE CWA BETWEEN 18 AND 00Z ON SATURDAY.
GUSTY WINDS AND COLDER AIR WILL FOLLOW THE FRONT.THE CHANCE FOR
RAIN SHOWERS WILL INCREASE OVER THE WESTERN PORTIONS OF THE CWA
WITH THE FROPA. VERY DRY AIR WILL QUICKLY FUNNEL INTO THE REGION
BEHIND THE FRONT... THUS THE CHANCE FOR SHOWERS WILL GREATLY
DIMINISH AFTER 03Z. RAIN IS EXPECTED FIRST AND AS THE COLDER AIR
MOVES IN... RAIN MAY TRANSITION OVER TO SNOW. BEHIND THE FROPA
THERE IS A BRIEF WINDOW FOR FREEZING DRIZZLE. THIS WINDOW IS
BETWEEN 06 AND 09Z SATURDAY AS VERY DRY AIR PUSHES IN. CONFIDENCE
IS NOT HIGH ON THIS SCENARIO... AND CLOSE ATTENTION WILL BE PAID
TO FUTURE MODEL RUNS TO DETERMINE IF THIS SITUATION IS
PLAUSIBLE... SO DECIDED TO LEAVE OUT OF CURRENT FORECAST FOR THE
TIME BEING.
EVEN THOUGH 850MB TEMPS WILL FALL TO -8 DEGREES CELSIUS MAKING
SATURDAY QUITE A CHILLY START... THE REAL COLD AIR WILL SURGE
INTO THE REGION LATE SATURDAY AFTERNOON/EARLY EVENING WITH A
SECONDARY COLD FRONT. 850MB TEMPS SUNDAY AFTERNOON WILL BE -19
DEGREES CELSIUS! THIS WILL BE A FIRST REAL TASTE OF COLD AIR OF
THE SEASON WITH TEMPERATURES REACHING THE UPPER TEENS TO LOW 20S
ACROSS THE CWA WITH WINDS SUSTAINED AROUND 15-20 MPH. WIND CHILL
VALUES WILL BE NEAR ZERO.
LE SNOW SHOWERS WILL BE LIKELY WITH RAPID COOLING ACROSS NY.
INITIAL FLOW BEHIND THE FROPA INDICATES A SINGLE BAND DEVELOPING
EAST OF LAKE ONTARIO THEN THE FLOW VEERING AND BECOMING MULTIBAND
ACROSS CENTRAL NY. MADE MINOR ADJUSTMENTS TO PREVIOUS FORECAST...
AND ADVISORY AND POTENTIALLY WARNING AMOUNT SNOWFALLS LOOK TO BE A
POSSIBILITY BY THE LATTER STAGE OF THE WEEKEND AND WILL CONTINUE
TO KEEP A CLOSE EYE ON THIS LE EVENT.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
230 AM UPDATE...
LONG TERM STARTS OUT WITH A NRN STREAM SYSTEM JUST SKIRTING OUR NRN
ZONES. UL FLOW BCMS MORE ZONAL DRG THE DAY MONDAY WITH TEMPS RISING
TO NR FRZG BY THE AFTN (STILL SOME 10F DEGREES BLO NORMAL) BUT WRMR
THAN SUNDAY.
DRG THE DAY TUESDAY, MED RANGE MODELS ARE VRY SLOWLY BEGINNING TO
COME TOGETHER ON DVLPMNT OF EVENTUAL COASTAL LOW. 00Z EC HAS COME
MORE INTO LINE WITH 00Z GFS WITH SRN STREAM WV RESULTING IN SFC
LOPRES DVLPNG ACRS NRN GOM BY 12Z TUESDAY. INDICATIONS ARE THAT NOW
PCPN WL OVRSPRD SRN PORTIONS OF CWA BY 12Z WED WITH PHASING OCCURRING
SOMETIME DRG THE DAY WED. 00Z EC HAS COME IN CLDR WITH H8 TEMPS THAN
PRIOR RUN BUT STILL TOO EARLY AT THIS POINT TO DETERMINE WHAT PTYPE
MAY EVENTUALLY BE. THAT IS ASSUMING THE SFC LOW TRACKS CLOSE ENUF TO
THE COAST TO IMPACT CWA. AT THIS TIME 00Z NAM IS RIGHT ON TARGET
WITH 00Z GFS/CMC AND EURO THRU THE LAST FRAME (12Z MON) WITH SRN
STREAM WV. HV MADE NO CHGS TO GRIDS FOR MID-WEEK AS IT IS TOO FAR
OUT AND WAY TOO EARLY TO JUMP ON ANYTHING AT THIS POINT SO AS TO
AVOID FLIP-FLOPPING ON HOLIDAY FCST.
SYSTEM EXITS OFF TO THE NORTHEAST SOMETIME WED AFTN/WED NGT. THIS
PULLS DOWN MUCH CLDR AIR FOR THANKSGIVING WITH THICKNESSES DROPPING
DOWN INTO THE LOW 500S. THUS WL LWR TEMPS SLIGHTLY FOR WED NGT/THUR.
THIS WL LKLY RESULT IN CONTD LES THRU THE END OF THE LONG TERM.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
06Z UPDATE...
LIGHT VFR SHOWERS MOVING ACROSS NY TERMINALS TONIGHT. MVFR CIGS AT
KAVP EARLY ON WITH LITTLE IN THE WAY OF SHOWERS BUT -SHRA SHOULD
MOVE INTO TERMINAL AFTER 10Z WITH MVFR RESTRICTIONS CONTINUING
THROUGH THE DAY.
FURTHER NORTH ACROSS NY TERMINALS, CONDITIONS EXPECTED TO
DETERIORATE TO MVFR AFTER 08Z OR 09Z DUE TO CIGS. MVFR
RESTRICTIONS EXPECTED THROUGH END OF TAF VALID TIME, THOUGH
POSSIBLE THAT CONDITIONS COULD IMPROVE TO VFR IMMEDIATELY
FOLLOWING COLD FRONTAL PASSAGE CLOSE TO 06Z. POTENTIAL WILL BE
POSSIBLE FOR IFR CIGS TOWARD 12Z THIS MORNING BUT CONFIDENCE IS
STILL TOO LOW AT THIS TIME TO INCLUDE MENTION IN TERMINALS.
COLD FRONT PASSAGE LOOKS TO OCCUR IN THE 00Z-03Z TIMEFRAME WITH
SHOWERS/MVFR CIGS EXPECTED ALONG THE FRONT.
LIGHT S-SE WINDS TONIGHT WILL BECOME SOUTHWESTERLY BTWN 5-10KTS
DURING THE AFTERNOON AHEAD OF CDFNT. FOLLOWING FROPA, WINDS QUICKLY
SHIFT AROUND TO THE NW WITH SUSTAINED 10-15KTS WITH GUSTS AROUND
20KTS.
OUTLOOK...
SAT...PRIMARILY VFR.
SAT NGT AND SUN...RESTRICTIONS LIKELY FROM LAKE EFFECT
SHSN...ESPECIALLY CENTRAL NY TERMINALS.
SUN NIGHT AND MON...MOSTLY VFR.
MON NIGHT/TUE...SOME RESTRICTIONS PSBL IN SCTD -SHSN.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...CMG
NEAR TERM...CMG
SHORT TERM...CMG/KAH
LONG TERM...PVN
AVIATION...PVN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
111 AM EST FRI NOV 22 2013
.SYNOPSIS...
WIDELY SCATTERED SHOWERS THIS MORNING WILL TAPPER OFF BY EARLY
AFTERNOON IN ADVANCE OF A COLD FRONT THAT WILL MOVE THROUGH THE
AREA LATER THIS EVENING. AS THIS FRONT CROSS THE AREA...EXPECT
SHOWERS TO REDEVELOP WITH RAINFALL THEN COMING TO AN END SHORTLY
AFTER MIDNIGHT. MOSTLY DRY CONDITIONS ON SATURDAY WILL QUICKLY
GIVE WAY TO DEVELOPING SNOW SHOWERS BY AFTERNOON AND EVENING AS A
STRONG ARCTIC COLD FRONT MOVES THROUGH THE AREA. AS THE COLDEST
AIRMASS OF THE SEASON DESCENDS UPON THE REGION...EXPECT DEVELOPING
LAKE EFFECT SNOWS SOUTHEAST OF LAKE ONTARIO. SNOW WILL INCREASE IN
INTENSITY SATURDAY NIGHT WITH HEAVY ACCUMULATIONS POSSIBLE FOR
PORTIONS OF CENTRAL NEW YORK.
&&
.NEAR TERM /THROUGH TONIGHT/...
1 AM UPDATE...
RAIN SHOWERS CONTINUING TO DEVELOP ACROSS THE REGION EARLY THIS
MORNING AS WARM AIR ADVECTION IN ADVANCE OF AN APPROACHING WARM
FRONT COMBINED WITH THE PASSAGE OF A WEAK SHORTWAVE IN WEST
SOUTHWEST FLOW ALOFT. HAVE INCREASED POPS BASED ON LATEST RADAR
TRENDS AND EXPECTATIONS FOR FURTHER MOVEMENT LATER THIS MORNING.
TEMPS/DEWPOINTS LOOK GOOD...NO REAL ADJUSTMENTS NEEDED AT THIS
TIME.
900 PM UPDATE...UPDATED TO SPEED UP THE ARRIVAL OF THE SHRA ACRS
SRN NY AND NE PA. LATEST HRRR MODEL REFLECTIVITY WAS A TRACK AND
UPDATED HOURLY POPS USING MODEL-RADAR SMART TOOL THRU 9Z. THE HRRR
SHOWS A WIDESPREAD AREA OF LIGHT SHRA SPREADING W-E INTO THE
OVERNIGHT. TEMPERATURES ACRS THE ENTIRE FORECAST AREA WERE ABV
FREEZING. UPPER MOHAWK VALLEY WILL NOT SEE ANY SIGNIFICANT MIXED
PRECIP AS PER LATEST RAP...NAM AND GFS MODEL SOUNDINGS AND ALSO
BNDRY LAYER TEMPS WHICH WERE ARND 40F. LATEST LAPS WET BULB TEMPS
WERE IN THE MID TO UPPER 30S IN ONEIDA CO SO THIS COMBINED WITH
LOW- LEVEL WAA SHUD PRECLUDE ANY CHANCE FOR FZRA AS PRECIP CONTS
TO WORK INTO THESE AREAS. SMALL CHC FOR A LITTLE IP BUT IT WON/T
BE SIGNIFICANT ENUF TO WARRANT MENTION IN GRIDS OR ANY PRODUCTS.
TWEAKED REST OF SHORT TERM GRIDS JUST A LITTLE. PREVIOUS DSCN IS
BELOW FROM 700 PM UPDATE..
700 PM UPDATE...AREA RADARS SHOWG SHRA SPREADING INTO WRN AND
CNTRL NY AND NW PA/NC PA AT THIS TIME. THESE SHRA WERE ASSCTD WITH
AN ACCELERATING SWRLY LOW-LEVEL JET ARND 850 MB WHICH WAS RISING
ISENTROPICALLY INTO NY AND NRN PA THIS EVE. THIS LL JET WAS TIED
TO AN UPPER LEVEL JET STREAK AND ASSCTD UPR WAVE WHICH WAS
PROPAGATING INTO THE GREAT LAKES AND UPR OH VLLY. THIS SHOT OF
ISEN LIFT/WAA WILL SHOOT THRU THE REGION BETWEEN 00Z AND 12Z FRI.
FOLLOWED LATEST HRRR FOR TIMING OF HOURLY POPS IN GRIDS TONIGHT AS
THIS MODEL SEEMS TO HAVE THE BEST HANDLE ON THE PRESENTLY EVOLVING
SHRA.
AFTER THIS FIRST UPR LVL WAVE AND ASSCTD LLJ PASSES E AND
WEAKENS BY 12Z...THERE WILL BE A LULL IN THE PRECIP FOR MUCH OF
FRI. I CAN SEE ISLD TO SCT SHRA ACVTY AT BEST AS WE WAIT FOR THE
NEXT LARGER SCALE UPR LVL WAVE TO MAKE A PUSH TO THE E INTO THE UPR
LAKES AND ONT BY 21Z FRI TO 00Z SAT. THIS WILL BE THE IMPETUS TO
PUSH THE SFC CD FRNT INTO WRN AND CNTRL NY LATE FRIDAY PM. HAVE
TRENDED POPS DOWNWARD FRI AM AND BRING THEM BACK UP BY LATE FRI AS
RESULT TO ACCOUNT FOR THIS LULL IN ACVTY. I MAY FURTHER REFINE THIS
WITH NEXT UPDATE AS WELL.
AS FOR PRECIP TYPE...I SEE ALL RAIN TONIGHT THRU FRI. MODEL
SOUNDING DATA IS QUITE WARM EVEN IN OUR COLDEST LOCATIONS IN THE
UPPER MOHAWK VALLEY AND CATSKILLS WHERE LL TEMPS ARE WELL ABV
FREEZING AT THE ONSET OF THIS EVE/S PRECIP. THE COLDER AIR DOES NOT
ARRIVE UNTIL FRI NGT TO TURN PRECIP TO SNOW BEFORE IT ENDS. SO
JUST PLAIN RAIN ALL DAY FRI.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
330 PM EST UPDATE...
THE CHANCE FOR RAIN SHOWERS WILL INCREASE EARLY FRIDAY MORNING
FROM WEST TO EAST AS THE ATMOSPHERIC COLUMN BECOMES SATURATED AND
STRONG ISENTROPIC LIFT REMAINS OVER NY/PA. THE BEST CHANCE FOR
RAIN SHOWERS FRIDAY MORNING WILL BE OVER THE WESTERN PORTIONS OF
THE CWA WHERE THE GREATEST UPPER LEVEL SUPPORT IS LOCATED. FRIDAY
AFTERNOON THERE WILL BE A BRIEF DECREASE IN ACTIVITY AHEAD OF AN
ADVANCING STRONG COLD FRONT/SFC TROUGH. THE COLD FRONT IS
EXPECTED TO PUSH INTO THE CWA BETWEEN 18 AND 00Z ON SATURDAY.
GUSTY WINDS AND COLDER AIR WILL FOLLOW THE FRONT.THE CHANCE FOR
RAIN SHOWERS WILL INCREASE OVER THE WESTERN PORTIONS OF THE CWA
WITH THE FROPA. VERY DRY AIR WILL QUICKLY FUNNEL INTO THE REGION
BEHIND THE FRONT... THUS THE CHANCE FOR SHOWERS WILL GREATLY
DIMINISH AFTER 03Z. RAIN IS EXPECTED FIRST AND AS THE COLDER AIR
MOVES IN... RAIN MAY TRANSITION OVER TO SNOW. BEHIND THE FROPA
THERE IS A BRIEF WINDOW FOR FREEZING DRIZZLE. THIS WINDOW IS
BETWEEN 06 AND 09Z SATURDAY AS VERY DRY AIR PUSHES IN. CONFIDENCE
IS NOT HIGH ON THIS SCENARIO... AND CLOSE ATTENTION WILL BE PAID
TO FUTURE MODEL RUNS TO DETERMINE IF THIS SITUATION IS
PLAUSIBLE... SO DECIDED TO LEAVE OUT OF CURRENT FORECAST FOR THE
TIME BEING.
EVEN THOUGH 850MB TEMPS WILL FALL TO -8 DEGREES CELSIUS MAKING
SATURDAY QUITE A CHILLY START... THE REAL COLD AIR WILL SURGE
INTO THE REGION LATE SATURDAY AFTERNOON/EARLY EVENING WITH A
SECONDARY COLD FRONT. 850MB TEMPS SUNDAY AFTERNOON WILL BE -19
DEGREES CELSIUS! THIS WILL BE A FIRST REAL TASTE OF COLD AIR OF
THE SEASON WITH TEMPERATURES REACHING THE UPPER TEENS TO LOW 20S
ACROSS THE CWA WITH WINDS SUSTAINED AROUND 15-20 MPH. WIND CHILL
VALUES WILL BE NEAR ZERO.
LE SNOW SHOWERS WILL BE LIKELY WITH RAPID COOLING ACROSS NY.
INITIAL FLOW BEHIND THE FROPA INDICATES A SINGLE BAND DEVELOPING
EAST OF LAKE ONTARIO THEN THE FLOW VEERING AND BECOMING MULTIBAND
ACROSS CENTRAL NY. MADE MINOR ADJUSTMENTS TO PREVIOUS FORECAST...
AND ADVISORY AND POTENTIALLY WARNING AMOUNT SNOWFALLS LOOK TO BE A
POSSIBILITY BY THE LATTER STAGE OF THE WEEKEND AND WILL CONTINUE
TO KEEP A CLOSE EYE ON THIS LE EVENT.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
EXTENDED PERIOD WILL FEATURE AN UPPER LEVEL TROF ACROSS THE
NORTHEAST WHICH WILL RESULT IN A CONTINUATION OF MUCH COOLER THAN
NORMAL TEMPERATURES. SUNDAY NIGHT THE ONGOING LAKE EFFECT SNOW
SHOWERS WILL GRADUALLY DIMINISH AS IT LIFTS NORTH ACROSS THE
NORTHERN CWA. MONDAY LOOKS PRIMARILY DRY AS SFC LOW PRES MOVES INTO
EASTERN CANADA AND THE ASSOCIATED WARM FRONT BRINGS JUST A SLIGHT
CHC OF SNOW SHOWERS TO THE NRN CWA. MONDAY NIGHT THROUGH WEDNESDAY
CONTINUED WITH CHC POPS FOR SNOW SHOWERS AS A NORTHERN STREAM SYSTEM
CONTINUES TRACKING THROUGH EASTERN CANADA AND DRAGS A TRAILING COLD
FRONT THROUGH THE REGION TUE NIGHT. BEHIND THIS FEATURE MORE COLD
AIR AND NORTHWEST FLOW IS EXPECTED WITH SCATTERED SNOW SHOWERS
ESPECIALLY SOUTHEAST OF LAKE ONTARIO.
LATEST ECMWF NOW SHOWS MORE PHASING WITH NRN/SRN STREAM TUE NIGHT
AND WED WITH A COASTAL SYSTEM BRUSHING THE REGION. ITS ALSO WARMER
INDICATING THE POTENTIAL FOR RAIN OVER THE E/SE PTN OF THE FA. THE
GFS CONTINUES TO SHOW SYSTEM PASSING WELL SOUTH OF THE AREA AND NOT
AFFECTING CENTRAL NY/NE PA. FOLLOWED WPC GUIDANCE WHICH KEEPS SYSTEM
SOUTHEAST OF FA AND POPS ONLY IN THE CHC CATEGORY.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
06Z UPDATE...
LIGHT VFR SHOWERS MOVING ACROSS NY TERMINALS TONIGHT. MVFR CIGS AT
KAVP EARLY ON WITH LITTLE IN THE WAY OF SHOWERS BUT -SHRA SHOULD
MOVE INTO TERMINAL AFTER 10Z WITH MVFR RESTRICTIONS CONTINUING
THROUGH THE DAY.
FURTHER NORTH ACROSS NY TERMINALS, CONDITIONS EXPECTED TO
DETERIORATE TO MVFR AFTER 08Z OR 09Z DUE TO CIGS. MVFR
RESTRICTIONS EXPECTED THROUGH END OF TAF VALID TIME, THOUGH
POSSIBLE THAT CONDITIONS COULD IMPROVE TO VFR IMMEDIATELY
FOLLOWING COLD FRONTAL PASSAGE CLOSE TO 06Z. POTENTIAL WILL BE
POSSIBLE FOR IFR CIGS TOWARD 12Z THIS MORNING BUT CONFIDENCE IS
STILL TOO LOW AT THIS TIME TO INCLUDE MENTION IN TERMINALS.
COLD FRONT PASSAGE LOOKS TO OCCUR IN THE 00Z-03Z TIMEFRAME WITH
SHOWERS/MVFR CIGS EXPECTED ALONG THE FRONT.
LIGHT S-SE WINDS TONIGHT WILL BECOME SOUTHWESTERLY BTWN 5-10KTS
DURING THE AFTERNOON AHEAD OF CDFNT. FOLLOWING FROPA, WINDS QUICKLY
SHIFT AROUND TO THE NW WITH SUSTAINED 10-15KTS WITH GUSTS AROUND
20KTS.
OUTLOOK...
SAT...PRIMARILY VFR.
SAT NGT AND SUN...RESTRICTIONS LIKELY FROM LAKE EFFECT
SHSN...ESPECIALLY CENTRAL NY TERMINALS.
SUN NIGHT AND MON...MOSTLY VFR.
MON NIGHT/TUE...SOME RESTRICTIONS PSBL IN SCTD -SHSN.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...CMG
NEAR TERM...CMG
SHORT TERM...CMG/KAH
LONG TERM...PVN/RRM
AVIATION...PVN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1248 AM EST FRI NOV 22 2013
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTH THROUGH THE AREA TONIGHT AND EARLY
FRIDAY AND BRING RAIN SHOWERS WITH IT. A COLD FRONT WILL SWEEP
THROUGH THE AREA LATER FRIDAY CHANGING ANY RAIN SHOWERS OVER TO
LIGHT SNOW SHOWERS OR FLURRIES FRIDAY NIGHT. A STRONGER COLDER FRONT
WILL SURGE ACROSS THE REGION SATURDAY NIGHT BRINGING ADDITIONAL
SNOW SHOWERS AND FLURRIES WITH UNSEASONABLY COLD AIR TO THE REGION
FOR SUNDAY AND MONDAY.
&&
.NEAR TERM /THROUGH TODAY/...
900 PM UPDATE...UPDATED TO SPEED UP THE ARRIVAL OF THE SHRA ACRS
SRN NY AND NE PA. LATEST HRRR MODEL REFLECTIVITY WAS A TRACK AND
UPDATED HOURLY POPS USING MODEL-RADAR SMART TOOL THRU 9Z. THE HRRR
SHOWS A WIDESPREAD AREA OF LIGHT SHRA SPREADING W-E INTO THE
OVERNIGHT. TEMPERATURES ACRS THE ENTIRE FORECAST AREA WERE ABV
FREEZING. UPPER MOHAWK VALLEY WILL NOT SEE ANY SIGNIFICANT MIXED
PRECIP AS PER LATEST RAP...NAM AND GFS MODEL SOUNDINGS AND ALSO BNDRY
LAYER TEMPS WHICH WERE ARND 40F. LATEST LAPS WET BULB TEMPS WERE
IN THE MID TO UPPER 30S IN ONEIDA CO SO THIS COMBINED WITH LOW-
LEVEL WAA SHUD PRECLUDE ANY CHANCE FOR FZRA AS PRECIP CONTS TO
WORK INTO THESE AREAS. SMALL CHC FOR A LITTLE IP BUT IT WON/T BE
SIGNIFICANT ENUF TO WARRANT MENTION IN GRIDS OR ANY PRODUCTS.
TWEAKED REST OF SHORT TERM GRIDS JUST A LITTLE.
PREVIOUS DSCN IS BELOW FROM 700 PM UPDATE..
700 PM UPDATE...AREA RADARS SHOWG SHRA SPREADING INTO WRN AND
CNTRL NY AND NW PA/NC PA AT THIS TIME. THESE SHRA WERE ASSCTD WITH
AN ACCELERATING SWRLY LOW-LEVEL JET ARND 850 MB WHICH WAS RISING
ISENTROPICALLY INTO NY AND NRN PA THIS EVE. THIS LL JET WAS TIED
TO AN UPPER LEVEL JET STREAK AND ASSCTD UPR WAVE WHICH WAS
PROPAGATING INTO THE GREAT LAKES AND UPR OH VLLY. THIS SHOT OF
ISEN LIFT/WAA WILL SHOOT THRU THE REGION BETWEEN 00Z AND 12Z FRI.
FOLLOWED LATEST HRRR FOR TIMING OF HOURLY POPS IN GRIDS TONIGHT AS
THIS MODEL SEEMS TO HAVE THE BEST HANDLE ON THE PRESENTLY EVOLVING
SHRA.
AFTER THIS FIRST UPR LVL WAVE AND ASSCTD LLJ PASSES E AND
WEAKENS BY 12Z...THERE WILL BE A LULL IN THE PRECIP FOR MUCH OF
FRI. I CAN SEE ISLD TO SCT SHRA ACVTY AT BEST AS WE WAIT FOR THE
NEXT LARGER SCALE UPR LVL WAVE TO MAKE A PUSH TO THE E INTO THE UPR
LAKES AND ONT BY 21Z FRI TO 00Z SAT. THIS WILL BE THE IMPETUS TO
PUSH THE SFC CD FRNT INTO WRN AND CNTRL NY LATE FRIDAY PM. HAVE
TRENDED POPS DOWNWARD FRI AM AND BRING THEM BACK UP BY LATE FRI AS
RESULT TO ACCOUNT FOR THIS LULL IN ACVTY. I MAY FURTHER REFINE THIS
WITH NEXT UPDATE AS WELL.
AS FOR PRECIP TYPE...I SEE ALL RAIN TONIGHT THRU FRI. MODEL
SOUNDING DATA IS QUITE WARM EVEN IN OUR COLDEST LOCATIONS IN THE
UPPER MOHAWK VALLEY AND CATSKILLS WHERE LL TEMPS ARE WELL ABV
FREEZING AT THE ONSET OF THIS EVE/S PRECIP. THE COLDER AIR DOES NOT
ARRIVE UNTIL FRI NGT TO TURN PRECIP TO SNOW BEFORE IT ENDS. SO
JUST PLAIN RAIN ALL DAY FRI.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY/...
330 PM EST UPDATE...
THE CHANCE FOR RAIN SHOWERS WILL INCREASE EARLY FRIDAY MORNING
FROM WEST TO EAST AS THE ATMOSPHERIC COLUMN BECOMES SATURATED AND
STRONG ISENTROPIC LIFT REMAINS OVER NY/PA. THE BEST CHANCE FOR
RAIN SHOWERS FRIDAY MORNING WILL BE OVER THE WESTERN PORTIONS OF
THE CWA WHERE THE GREATEST UPPER LEVEL SUPPORT IS LOCATED. FRIDAY
AFTERNOON THERE WILL BE A BRIEF DECREASE IN ACTIVITY AHEAD OF AN
ADVANCING STRONG COLD FRONT/SFC TROUGH. THE COLD FRONT IS
EXPECTED TO PUSH INTO THE CWA BETWEEN 18 AND 00Z ON SATURDAY.
GUSTY WINDS AND COLDER AIR WILL FOLLOW THE FRONT.THE CHANCE FOR
RAIN SHOWERS WILL INCREASE OVER THE WESTERN PORTIONS OF THE CWA
WITH THE FROPA. VERY DRY AIR WILL QUICKLY FUNNEL INTO THE REGION
BEHIND THE FRONT... THUS THE CHANCE FOR SHOWERS WILL GREATLY
DIMINISH AFTER 03Z. RAIN IS EXPECTED FIRST AND AS THE COLDER AIR
MOVES IN... RAIN MAY TRANSITION OVER TO SNOW. BEHIND THE FROPA
THERE IS A BRIEF WINDOW FOR FREEZING DRIZZLE. THIS WINDOW IS
BETWEEN 06 AND 09Z SATURDAY AS VERY DRY AIR PUSHES IN. CONFIDENCE
IS NOT HIGH ON THIS SCENARIO... AND CLOSE ATTENTION WILL BE PAID
TO FUTURE MODEL RUNS TO DETERMINE IF THIS SITUATION IS
PLAUSIBLE... SO DECIDED TO LEAVE OUT OF CURRENT FORECAST FOR THE
TIME BEING.
EVEN THOUGH 850MB TEMPS WILL FALL TO -8 DEGREES CELSIUS MAKING
SATURDAY QUITE A CHILLY START... THE REAL COLD AIR WILL SURGE
INTO THE REGION LATE SATURDAY AFTERNOON/EARLY EVENING WITH A
SECONDARY COLD FRONT. 850MB TEMPS SUNDAY AFTERNOON WILL BE -19
DEGREES CELSIUS! THIS WILL BE A FIRST REAL TASTE OF COLD AIR OF
THE SEASON WITH TEMPERATURES REACHING THE UPPER TEENS TO LOW 20S
ACROSS THE CWA WITH WINDS SUSTAINED AROUND 15-20 MPH. WIND CHILL
VALUES WILL BE NEAR ZERO.
LE SNOW SHOWERS WILL BE LIKELY WITH RAPID COOLING ACROSS NY.
INITIAL FLOW BEHIND THE FROPA INDICATES A SINGLE BAND DEVELOPING
EAST OF LAKE ONTARIO THEN THE FLOW VEERING AND BECOMING MULTIBAND
ACROSS CENTRAL NY. MADE MINOR ADJUSTMENTS TO PREVIOUS FORECAST...
AND ADVISORY AND POTENTIALLY WARNING AMOUNT SNOWFALLS LOOK TO BE A
POSSIBILITY BY THE LATTER STAGE OF THE WEEKEND AND WILL CONTINUE
TO KEEP A CLOSE EYE ON THIS LE EVENT.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
EXTENDED PERIOD WILL FEATURE AN UPPER LEVEL TROF ACROSS THE
NORTHEAST WHICH WILL RESULT IN A CONTINUATION OF MUCH COOLER THAN
NORMAL TEMPERATURES. SUNDAY NIGHT THE ONGOING LAKE EFFECT SNOW
SHOWERS WILL GRADUALLY DIMINISH AS IT LIFTS NORTH ACROSS THE
NORTHERN CWA. MONDAY LOOKS PRIMARILY DRY AS SFC LOW PRES MOVES INTO
EASTERN CANADA AND THE ASSOCIATED WARM FRONT BRINGS JUST A SLIGHT
CHC OF SNOW SHOWERS TO THE NRN CWA. MONDAY NIGHT THROUGH WEDNESDAY
CONTINUED WITH CHC POPS FOR SNOW SHOWERS AS A NORTHERN STREAM SYSTEM
CONTINUES TRACKING THROUGH EASTERN CANADA AND DRAGS A TRAILING COLD
FRONT THROUGH THE REGION TUE NIGHT. BEHIND THIS FEATURE MORE COLD
AIR AND NORTHWEST FLOW IS EXPECTED WITH SCATTERED SNOW SHOWERS
ESPECIALLY SOUTHEAST OF LAKE ONTARIO.
LATEST ECMWF NOW SHOWS MORE PHASING WITH NRN/SRN STREAM TUE NIGHT
AND WED WITH A COASTAL SYSTEM BRUSHING THE REGION. ITS ALSO WARMER
INDICATING THE POTENTIAL FOR RAIN OVER THE E/SE PTN OF THE FA. THE
GFS CONTINUES TO SHOW SYSTEM PASSING WELL SOUTH OF THE AREA AND NOT
AFFECTING CENTRAL NY/NE PA. FOLLOWED WPC GUIDANCE WHICH KEEPS SYSTEM
SOUTHEAST OF FA AND POPS ONLY IN THE CHC CATEGORY.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
06Z UPDATE...
LIGHT VFR SHOWERS MOVING ACROSS NY TERMINALS TONIGHT. MVFR CIGS AT
KAVP EARLY ON WITH LITTLE IN THE WAY OF SHOWERS BUT -SHRA SHOULD
MOVE INTO TERMINAL AFTER 10Z WITH MVFR RESTRICTIONS CONTINUING
THROUGH THE DAY.
FURTHER NORTH ACROSS NY TERMINALS, CONDITIONS EXPECTED TO
DETERIORATE TO MVFR AFTER 08Z OR 09Z DUE TO CIGS. MVFR
RESTRICTIONS EXPECTED THROUGH END OF TAF VALID TIME, THOUGH
POSSIBLE THAT CONDITIONS COULD IMPROVE TO VFR IMMEDIATELY
FOLLOWING COLD FRONTAL PASSAGE CLOSE TO 06Z. POTENTIAL WILL BE
POSSIBLE FOR IFR CIGS TOWARD 12Z THIS MORNING BUT CONFIDENCE IS
STILL TOO LOW AT THIS TIME TO INCLUDE MENTION IN TERMINALS.
COLD FRONT PASSAGE LOOKS TO OCCUR IN THE 00Z-03Z TIMEFRAME WITH
SHOWERS/MVFR CIGS EXPECTED ALONG THE FRONT.
LIGHT S-SE WINDS TONIGHT WILL BECOME SOUTHWESTERLY BTWN 5-10KTS
DURING THE AFTERNOON AHEAD OF CDFNT. FOLLOWING FROPA, WINDS QUICKLY
SHIFT AROUND TO THE NW WITH SUSTAINED 10-15KTS WITH GUSTS AROUND
20KTS.
OUTLOOK...
SAT...PRIMARILY VFR.
SAT NGT AND SUN...RESTRICTIONS LIKELY FROM LAKE EFFECT
SHSN...ESPECIALLY CENTRAL NY TERMINALS.
SUN NIGHT AND MON...MOSTLY VFR.
MON NIGHT/TUE...SOME RESTRICTIONS PSBL IN SCTD -SHSN.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...KAH
LONG TERM...PVN/RRM
AVIATION...PVN
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
635 AM EST FRI NOV 22 2013
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL WEAKEN AND SHIFT SOUTH ACROSS THE
CAROLINAS LATER TODAY. A STRONG ARCTIC COLD FRONT WILL CROSS THE
AREA LATE SATURDAY FOLLOWED BY THE COLDEST TEMPERATURES OF THE
SEASON. A SIGNIFICANT RAIN EVENT APPEARS LIKELY FOR THE MIDDLE OF
NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM FRIDAY...A SURFACE RIDGE OF HIGH PRESSURE EXTENDING
FROM NORTHERN NORTH CAROLINA TO A FEW HUNDRED MILES EAST OF THE NEW
JERSEY COAST WILL SINK SOUTH TODAY WHILE WEAKENING...MOVING ACROSS
OUR PORTION OF THE EASTERN CAROLINAS DURING THE AFTERNOON HOURS. THE
LOW LEVEL WINDS REMAIN ONSHORE...THEREFORE I ANTICIPATE ANOTHER MILD
DAY FOR MID-NOVEMBER WITH 850 MB TEMPS AROUND +10C. YESTERDAY`S
MAJOR CONCERN WAS CLOUD COVER...AND THIS IS AGAIN A CONCERN FOR
TODAY. MOISTURE POOLED AT THE BASE OF A SUBSIDENCE INVERSION ALOFT
IS MAINTAINING EXPANSIVE AREAS OF ALTOCUMULUS ACROSS THE CAROLINAS
EARLY THIS MORNING. THIS SUBSIDENCE INVERSION SHOULD DISSIPATE
DURING THE AFTERNOON HOURS...AND WEAK 300-305K ISENTROPIC LIFT MAY
NOT BE ENOUGH TO PRODUCE AN OVERCAST SKY BY ITSELF. FOR THIS REASON
I AM FORECASTING SKIES TO BECOME PARTLY CLOUDY BY AFTERNOON
IN ALL BUT THE INTERIOR PORTIONS OF SE NORTH CAROLINA AND THE
NORTHERN PEE DEE REGION.
ASSUMING WE GET THE AMOUNT OF SUNSHINE I AM ANTICIPATING...HIGHS
SHOULD REACH 72-75 AWAY FROM THE BEACHES TODAY. THIS IS VERY CLOSE
TO THE 00Z NAM WHICH PERFORMED EXTREMELY WELL WITH YESTERDAY`S
TRICKY FORECAST. THE 06Z MODELS DID NOT CHANGE APPRECIABLY VERSUS
THEIR 00Z COUNTERPARTS. THE NAM STILL LOOKS GOOD AND NOW HAS SUPPORT
FROM THE 10Z RUC WITH REGARD TO TEMPERATURES.
TONIGHT THE SURFACE RIDGE WILL WEAKEN FURTHER AND SHIFT WELL SOUTH
OF THE CAROLINAS...PRODUCING A LIGHT SOUTHWEST SURFACE WIND MOST OF
THE NIGHT. INCREASING DEEP-LAYER MOISTURE SHOULD RESULT IN SKIES
BECOMING INCREASINGLY CLOUDY OVERNIGHT...AND A FEW SHOWERS COULD
DEVELOP LATE. A WEAK LOW LEVEL JET WILL HELP HOLD TEMPERATURES
WELL-ABOVE NORMAL FOR THE DATE: LOWS ARE EXPECTED TO REACH THE MID
50S INLAND WITH SOME UPPER 50S NEAR THE COAST.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 AM FRIDAY...SWEEPING MID LEVEL TROUGH FROM THE NORTHERN
BRANCH OF THE SPLIT FLOW WILL BE THE MAIN FOCUS FOR THE SHORT TERM.
THE COLD FRONT ASSOCIATED WITH THIS FEATURE MOVES ACROSS SATURDAY.
THE LATEST GUIDANCE HAS TRENDED LOWER ON MAX TEMPERATURES FOR
SATURDAY DUE TO LESS INSOLATION. GUIDANCE POPS...MOST NOTABLY THE
MET NUMBERS HAVE JUMPED UP AND ARE NOW IN THE CATEGORICAL RANGE FOR
ALL STATIONS. FOR THIS REASON I HAVE INCREASED POPS TO LIKELY VALUES
FOR SATURDAY AFTERNOON. BY 0000 UTC SUNDAY THE FRONT HAS MOVED SOUTH
OF THE AREA AND THE COLD AIR ADVECTION ARRIVES IN FORCE. LATEST
850MB TEMPERATURES VIA THE GFS ARE NOT QUIET AS COLD SO IT SHOULD
NOT BE A BRUTAL DAY SUNDAY BUT MAX TEMPERATURES STILL LOOK TO REMAIN
BELOW 50 ACROSS ALL AREAS. FOR MONDAY MORNING LOWS...THE STORY WILL
BE WARM AIR ADVECTION ALOFT WITH THE VERY DRY/SHALLOW AND COLD
AIRMASS AT THE SURFACE. WITH A COUPLE OF DAYS IN THE 70S GROUND
TEMPERATES SHOULD KEEP LOWS IN THE MID 20S AREA WIDE.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 AM FRIDAY...FOCUS REMAINS ON THE SOUTHERN STREAM SYSTEM TO
IMPACT THE AREA TUESDAY AND WEDNESDAY. MEDIUM RANGE GUIDANCE REMAINS
CONSISTENT ON A SLOW MOVING MID LEVEL LOW MOVING OUT OF THE FOUR
CORNERS REGION WITH A SURFACE LOW DEVELOPING IN THE GULF OF MEXICO.
THERE REMAINS UNCERTAINTY AS TO WHICH TYPE OF SURFACE LOW
DEVELOPS... A MILLER A OR B SCENARIO BUT ONCE AGAIN THIS FAR OUT IN
TIME...THIS ISN/T CRITICAL AS OF YET. AS WE MOVE CLOSER...THE TRACK
AND TYPE WILL BECOME INCREASINGLY IMPORTANT AS TO THE TYPE AND
AMOUNT OF QPF. I HAVE MAINTAINED THE LIKELY POPS FOR TUESDAY AND
WEDNESDAY WHILE SHOWING RESTRAINT FROM INCREASING POPS THIS FAR OUT
IN TIME. TEMPERATURE TRENDS REMAIN ALL BUT UNCHANGED AS THE MOISTURE
WILL LIMIT VOLATILITY. I SUPPOSE THE BIG STORY RELATIVELY SPEAKING
IS THANKSGIVING DAY SHOULD BE DRY AS THE SYSTEM DEPARTS.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 12Z...SURFACE OBS INDICATE PATCHY AREAS OF DENSE FOG AND
STRATUS HAVE DEVELOPED WITHIN OUR CWA. KILM...KCRE AND KMYR ARE ALL
REPORTING LIFR CONDITIONS THIS MORNING. WHILE VSBYS SHOULD IMPROVE
BY 13-14Z...LIFR/IFR CIGS COULD PERSIST ALONG THE COAST THROUGH MID
MORNING. KCRE/KMYR HAVE HAD THE MOST PERSISTENT LIFR FOG/STRATUS...
SO THESE TERMS WILL LIKELY BE THE LAST TO BECOME VFR. AFTERWARDS...
VFR WILL PREVAIL TODAY WITH LIGHT AND VARIABLE WINDS EARLY BECOMING
SOUTH 5-8 KTS IN THE AFTN. LOW TO MID LEVEL CLOUDS WILL INCREASE
OVERNIGHT AS THE COLUMN MOISTENS AHEAD OF A COLD FRONT. CONDITIONS
AT KLBT/KFLO/KILM WILL LIKELY DETERIORATE TO AT LEAST MVFR BY THE
END OF THE PERIOD AS THE FRONT APPROACHES. HAVE ALSO ADDED VCSH FOR
THESE SITES AFTER 09Z SATURDAY. SHOWERS AT KCRE/KMYR WILL LIKELY
HOLD OFF UNTIL AFTER 12Z.
EXTENDED OUTLOOK...SCATTERED SHOWERS AND MVFR/IFR CIGS POSSIBLE
SATURDAY WITH A COLD FRONT. EXPECT BREEZY CONDITIONS FOLLOWING FROPA
ON SUNDAY. VFR ON MONDAY. SHOWERS LIKELY ON TUESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM FRIDAY...A WEAKENING RIDGE OF HIGH PRESSURE EXTENDING
FROM NORTHERN NORTH CAROLINA TO A FEW HUNDRED MILES EAST OF NEW
JERSEY WILL SETTLE SOUTH ACROSS THE CAROLINA COASTAL WATERS LATE
THIS AFTERNOON. UNTIL THIS RIDGE AXIS GETS HERE WIND DIRECTIONS WILL
REMAIN GENERALLY EAST TO NORTHEASTERLY WITH SPEEDS DIMINISHING
THROUGHOUT THE DAY. THE RIDGE SHOULD SINK SOUTH OF THE AREA THIS
EVENING WITH OUR WINDS VEERING TO THE SOUTHWEST AND EVENTUALLY WEST
LATE TONIGHT IN ADVANCE OF A STRONG ARCTIC FRONT SCHEDULED FOR
TOMORROW.
MODELS HAVE MINOR TIMING DIFFERENCES WITH REGARDS TO WHEN THE RIDGE
AXIS MOVES ACROSS THE AREA...BUT NONE CHANGE THE FORECAST
APPRECIABLY. SEAS HAVE FALLEN TO 5 FEET OUT AT THE FRYING PAN SHOALS
BUOY...AND SHOULD SUBSIDE TO 4 FT TONIGHT...WITH A 10-11 SECOND
EASTERLY SWELL PROVIDING MOST OF THE WAVE ENERGY OBSERVED TODAY.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 AM FRIDAY...THE FORECAST CHALLENGE FOR THE COASTAL WATERS
IS THE STRONG WINDS ARRIVING SATURDAY NIGHT IN THE WAKE OF A STRONG
COLD FRONT. SUSTAINED WINDS HAVE BACKED OFF EVER SO SLIGHTLY AND
GUSTS NOW ARE JUST BELOW GALE CRITERIA. CERTAINLY A SMALL CRAFT
ADVISORY IS A SLAM DUNK BUT A BRIEF GALE WARNING IS A LITTLE MORE IN
QUESTION. STILL LATE SATURDAY AND SUNDAY WILL NOT BE PLEASANT FOR
MARINERS WITH SUSTAINED NORTH WINDS OF 25-30 KNOTS EARLY DROPPING TO
15-20 KNOTS LATE SUNDAY. FOR MOST OF THE DAY SATURDAY A PRE FRONTAL
WESTERLY FLOW OF 10-15 KNOTS SHOULD PREVAIL. SIGNIFICANT SEAS ARE
MANAGEABLE MOST OF SATURDAY WITH 1-3 FEET. HOWEVER BY EARLY SUNDAY
HEIGHTS BUILD WITH THE STRONGER WINDS TO 4-6 FEET WITH THE HIGHER
SEAS ACROSS THE OUTER WATERS.
LONG TERM /MONDAY THROUGH TUESDAY/...
AS OF 300 AM FRIDAY...COASTAL WATERS WILL BE IN TRANSITION AS THE
SMALL CRAFT AND POSSIBLY GALE HEADLINE FROM SUNDAY WILL BE LONG
GONE. A MODEST NORTHEAST FLOW WILL BE IN PLACE EARLY MONDAY ON THE
ORDER OF 10-15 KNOTS DROPPING TO AROUND TEN KNOTS OR LESS BY DAYS
END. FOR TUESDAY A WEAK EAST TO SOUTHEAST FLOW WILL DEVELOP AS THE
HIGH MOVES OFF AND THE STORM SYSTEM IN THE GULF OF MEXICO MAKES ITS
MOVE. SPEEDS REMAIN TEPID TEN KNOTS OR LESS. RESIDUAL SEAS OF 2-4
FEET WILL BE IN PLACE MONDAY MORNING DROPPING TO 1-3 FEET LATE
MONDAY AND CONTINUING INTO TUESDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...BJR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1238 AM EST FRI NOV 22 2013
.SYNOPSIS...
A COASTAL TROUGH WILL BRING PERIODS OF ATLANTIC CLOUD COVER ONSHORE
THROUGH FRIDAY. A COLD FRONT WILL CROSS THE AREA SATURDAY FOLLOWED
BY A BRIEF PERIOD OF VERY COLD AIR. A SIGNIFICANT RAIN EVENT IS
BECOMING MORE LIKELY TOWARD THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 1230 AM FRIDAY...QUITE A FEW CHANGES TO THE FORECAST ARE
NEEDED AT THE CURRENT TIME. FIRST OF ALL...SKIES ARE OVERCAST IN A
COMBINATION OF LOW AND MID LEVEL CLOUDS AND SHOULD REMAIN THAT WAY
THROUGH DAYBREAK FOR ALL BUT PERHAPS WILLIAMSBURG AND GEORGETOWN
COUNTIES IN SOUTH CAROLINA. THIS WILL PREVENT ANYTHING APPROACHING
IDEAL RADIATIONAL COOLING AND I HAVE THEREFORE RAISED LOW
TEMPERATURES BY SEVERAL DEGREES. ISENTROPIC LIFT OCCURRING WITHIN
THE LAYER OF ALTOCUMULUS ACROSS THE SANDHILLS REGION IS PRODUCING
LIGHT SHOWERS BLOSSOMING ON RADAR NEAR BENNETTSVILLE AND LUMBERTON.
MODELS REVEAL THIS IS ASSOCIATED WITH AN AREA OF ISENTROPIC LIFT
ALONG THE 295-300K SURFACES WHICH SHOULD GRADUALLY DIMINISH OVER THE
NEXT 3 HOURS. I HAVE PLACED A 20-30 POP HERE THROUGH 09Z.
ELSEWHERE...VERY LOW CEILINGS THAT HAVE DEVELOPED ACROSS THE
"DOWNEAST" PORTION OF EXTREME EASTERN NC ARE ADVECTING WESTWARD WITH
THE ONSHORE WINDS. CEILINGS IN WILMINGTON...JACKSONVILLE AND
KENANSVILLE ARE DOWN TO 200-300 FT. THIS LOW CLOUD DECK MAY PUSH
WEST AND UNDERCUT THE MID-LEVEL CLOUDS FARTHER INLAND. CLOUD DEPTH
IS PROBABLY TOO THIN FOR DRIZZLE ACCORDING TO THE WELL-INITIALIZED
00Z NAM.
PREVIOUS DISCUSSION FROM 1030 PM FOLLOWS...
LATEST HRRR AND SREF PROBABILITY FOR MEASURABLE PRECIP...KEEP THE
BEST CHANCES...ALBEIT SMALL...OVER THE ADJACENT ATL WATERS MAINLY
JUST OFFSHORE AND ALONG A WEAK INVERTED SFC TROF. LOOKING AT VARIOUS
MODEL TIME HEIGHT DISPLAYS ACROSS THE FA...YIELDS AN ABUNDANCE OF
LOW LEVEL MOISTURE THAT WILL BE CONDUCIVE FOR STRATOCU AND STRATUS
BELOW 1K FT. THEREFORE...SKY CONDITIONS WILL REMAIN MOSTLY OR
VARIABLY CLOUDY FOR THE REMAINDER OF THE OVERNIGHT. THIS WILL PLACE
THE FOG POTENTIAL ON THE LOWER/LESSER SIDE OF OCCURRENCE BUT
NEVERTHELESS ENOUGH TO CONTINUE WITH PATCHY AND/OR AREAS OF FOG.
LATEST NAM AND GFS MODEL MOS GUIDANCE ARE QUITE SIMILAR WITH THEIR
LOWS FOR TONIGHT AND SEE NO REASON TO DETOUR FROM THEIR OVERALL
NUMBERS. THE ONLY CHANGE WILL ALONG THE IMMEDIATE BEACHES WHERE SFC
DEWPOINTS ARE RUNNING HIGHER THAN GUIDANCE WHICH WILL KEEP THE MINS
A FEW DEGREES HIGHER OVERNIGHT.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
AS OF 230 PM THURSDAY...HIGH PRESSURE REMAINS ACROSS THE AREA ON
FRIDAY WITH A WEAK TROUGHINESS EVIDENT JUST OFF THE COAST. THE
FORMER WILL SPONSOR UNSEASONABLY WARM TEMPERATURES WHILE THE LATTER
MAKES IT TOUGH TO RULE OUT THE OCCASIONAL SPRINKLE. HAVE NOT LIMITED
THE VERY LOW POPS TO JUST THE COAST HOWEVER AS SOME GUIDANCE SHOWING
VERY GOOD SIGNAL FOR SHALLOW CONVECTION FURTHER INLAND ALONG A LATE
SEASON SEA BREEZE. COLD FRONT WILL BE APPROACHING FROM THE NORTHWEST
AND THIS WILL HELP TO KEEP TEMPS QUITE MILD FRIDAY NIGHT WITH LOWS
ONLY DIPPING INTO THE MID OR UPPER 50S. THE CHANCE FOR MAINLY
NON-MEASURABLE PRECIP WILL CONTINUE. ARCTIC FRONT NOW A LITTLE
FASTER AND LOOKS TO BLAST THROUGH FAR NW ZONES BY MORNING AND AROUND
MIDDAY FURTHER SOUTH AND EAST. THIS HAS CAST SOME SERIOUS DOUBTS ON
SATURDAY`S HIGH TEMPERATURE FORECAST. ALTHOUGH THE MORNING HOURS
SHOULD FEATURE A RAPID JUMP OFF OF NIGHTTIME LOWS THE PASSAGE OF THE
FRONT WILL OBVIOUSLY SHARPLY REVERSE THAT TREND. HOW SOON THIS
HAPPENS WILL HAVE A GREAT IMPACT ON WHAT TEMPS ARE ACHIEVED...BEFORE
THEY START TO TUMBLE EARLIER THAN NORMAL BEHIND THE BOUNDARY. HAVE
TRIMMED HIGHS SOME FOR THIS REASON. A LOT OF TIMES THE STRONG CAA
LAGS A BIT BEHIND THE BOUNDARY HERE IN THE EASTERN CAROLINAS AS THE
PASSAGE ACROSS THE MOUNTAINS FRACTURES THE BOUNDARY IN THE VERTICAL.
THIS WILL ALSO PROBABLY YIELD QUITE A SPREAD IN THE ACTUAL HIGHS
ACHIEVED FROM NW TO SE AND HAVE ADJUSTED FCST ACCORDINGLY.
PREFRONTAL MOISTURE ADVECTION IS LACKLUSTER AND DYNAMICS ALOFT STAY
WELL REMOVED TO OUR NORTH. RAINFALL CHANCES APPEAR TO ONLY WARRANT
CHANCE AND QPF SHOULD BE QUITE MINIMAL.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 230 PM THURSDAY...PERIOD BEGINS QUIET AND COLD WITH HIGH
PRESSURE BUILDING IN FROM THE NORTHWEST. STRONG COLD ADVECTION SUN
WILL HELP KEEP HIGHS FROM REACHING 50 IN MOST PLACES. PROXIMITY TO
SURFACE RIDGE AXIS SUN NIGHT WILL ALLOW SOME RADIATIONAL EFFECT. HOW
STRONG REMAINS IN QUESTION BUT LOWS WILL FALL INTO THE MID 20S.
SURFACE RIDGE AXIS SLOWLY SHIFTS OFFSHORE MON BUT RETURN FLOW NEVER
REALLY DEVELOPS WITH WEAK WEDGE SETTING UP. MON AND MON NIGHT WILL
AGAIN BE COOL AND DRY WITH TEMPERATURES REMAINING BELOW CLIMO. LATE
MON INTO MON NIGHT INCREASING MOISTURE ALOFT AHEAD OF GULF COAST
SYSTEM LEADS TO INCREASING AND SLOWLY LOWERING CLOUD DECK.
SOUTHERN STREAM SYSTEM EMERGING FROM THE SOUTHWEST EARLY NEXT WEEK
WILL BE PROVIDE THE NEXT BATCH OF SIGNIFICANT WEATHER FOR THE
SOUTHEAST DURING THE MIDDLE OF NEXT WEEK. AS THE UPPER LOW EMERGES
OVER THE NORTHERN GULF OF MEXICO IT WILL START TO OPEN UP. THE
LOCATION AND TIMING OF THIS FEATURE REMAINS IN QUESTION AND IS THE
SOURCE OF CONSIDERABLE FORECAST UNCERTAINTY. AT THE SAME TIME A WEAK
COASTAL TROUGH STARTS TO DEVELOP OFF THE CAROLINA COAST. INCREASING
MOISTURE AHEAD OF THE 5H LOW AND ISENTROPIC LIFT ARE LIKELY TO LEAD
TO LIGHT RAIN INCREASING OVER THE AREA TUE AND TUE NIGHT. HAVE
INCREASED POP TO LIKELY. ALSO HAVE QUESTIONS ABOUT HOW THE MID LEVEL
AND SURFACE PATTERN EVOLVE TUE INTO WED. CANNOT RULE OUT A COASTAL
LOW DEVELOPING ALONG THE TROUGH...SOMETHING THE GFS HAS BEEN
SHOWING. THE ECMWF ON THE OTHER HAND MOVES THE TROUGH INLAND WITH
THE SURFACE LOW TRACKING WEST OF THE AREA INSTEAD OF JUMPING OFF THE
COAST. WHILE EITHER SOLUTION IS LIKELY TO RESULT IN PRECIP FALLING
IN THE AREA THE DIFFERENCE LIES IN THE TIMING AND TEMPERATURE
POTENTIAL. GIVEN THE UNCERTAINTY WILL NOT MAKE A LOT OF CHANGES TO
THE EXTENDED. HAVE MAINTAINED POP INTO WED NIGHT WITH HIGHS BELOW
CLIMO AND LOWS NEAR CLIMO.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 06Z...LOW LEVEL EAST WIND IS BRINGING PLENTY OF ATLANTIC
MOISTURE ONSHORE. IN SE NORTH CAROLINA A LAYER OF VERY LOW STRATUS
(200-300 FOOT CEILINGS) HAS DEVELOPED OVER ILM EXTENDING NORTH
TOWARD NEW BERN AND MOREHEAD CITY. LINEAR EXTRAPOLATION SHOWS THIS
CLOUD DECK COULD GET INTO LBT AFTER 09Z...AND MAY EVEN CLIP CRE FOR
A FEW HOURS BEFORE WINDS JUST ABOVE THE SURFACE VEER MORE
SOUTHEASTERLY AROUND 10Z. A HEFTY MID LEVEL DECK OF ALTOCUMULUS ALOFT
SHOULD PREVENT ANYTHING APPROACHING IDEAL RADIATIONAL COOLING
THROUGH DAYBREAK. THIS IS NOT TO SAY LOW VSBY IN FOG AND/OR
ADDITIONAL LOW CEILINGS WON`T OCCUR...JUST THAT THE PROBABILITY IS
MUCH LOWER THAN IF WE HAD CLEAR MID LEVELS. A BATCH OF LIGHT SHOWERS
IN THE LBT VCNTY IS FALLING FROM THE MID LEVEL ALTOCUMULUS CLOUDS
AND SHOULD NOT SUBSTANTIALLY AFFECT VSBY.
AFTER DAYBREAK FLIGHT CATEGORY SHOULD IMPROVE TO VFR BY 13-15Z AS
SURFACE WINDS VEER TO THE SOUTH AND SOUTHWEST.
EXTENDED OUTLOOK...CHANCE OF SHOWERS/MVFR CIGS ON SATURDAY WITH A
COLD FRONT. VFR SUNDAY AND MONDAY. EXPECT GUSTY NORTH WINDS ON
SUNDAY BEHIND THE FRONT. INCREASING CHANCE FOR SHOWERS ON TUESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 AM FRIDAY...NO SIGNIFICANT CHANGES ARE NEEDED TO THE
FORECAST. PREVIOUS DISCUSSION FROM 1030 PM FOLLOWS...
THE BORDERLINE SCA FOR THE NC COASTAL WATERS CONTINUES THROUGH 3
AM...MAINLY DUE TO SIGNIFICANT SEAS STAYING RIGHT AT SCA THRESHOLDS
ACROSS THE OUTER WATERS OFF CAPE FEAR. THE BASIC TREND FOR THE
OVERNIGHT PERIOD WILL LIE WITH THE BROAD CENTER OF HIGH PRESSURE
DROPPING SOUTH AND EVENTUALLY PARKING ITSELF ACROSS THE CAROLINAS
AND ADJACENT ATL WATERS BY DAYTIME FRIDAY. THE WEAK INVERTED SFC
TROF THIS EVENING WILL AID THE ENE-E WIND DIRECTION. DEPENDING ON
HOW THE BROAD CENTER OF HIGH PRESSURE ORIENTS ITSELF ACROSS THE
FORECAST AREA...ONSHORE WINDS SHOULD PREVAIL WITH DIMINISHED SPEEDS
IE. 10-15 KT OVERNIGHT DUE TO A RELAXING SFC PG. SIGNIFICANT SEAS
WILL HOLD IN THE 3 TO 6 FOOT RANGE OVERNIGHT...WITH THE 6 FOOTERS
PRIMARILY OCCURRING ACROSS THE OUTER WATERS OFF CAPE FEAR INTO THE
PRE-DAWN HOURS. DOMINANT PERIODS WILL RANGE BETWEEN 8 AND 10 SECONDS.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 230 PM THURSDAY...THE PERIOD STARTS OFF RATHER QUIET WITH HIGH
PRESSURE CENTERED OVER GA AND WEAKENING. MEANWHILE A WEAK
TROUGHINESS WILL BE FOUND ALONG THE COAST. WINDS SHOULD BE CAPPED AT
JUST 10 KT OUT OF THE SOUTH. SOME VEERING ON FRIDAY NIGHT IS IN
RESPONSE TO BOTH THE FURTHER WEAKENING OF THE HIGH AS WELL AS THE
APPROACH OF A STRONG COLD FRONT. THIS BOUNDARY WILL PUSH ACROSS THE
WATERS SATURDAY EVENING LEADING TO A VERY SHARP VEER. THE INCREASE
IN WIND SPEEDS HOWEVER WILL BE MORE GRADUAL. ANY HEADLINE OR
ADVISORY CONDITIONS...IF THEY OCCUR...APPEAR SLATED FOR THE LONG
TERM.
LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 230 PM THURSDAY...STRONG COLD ADVECTION AND PINCHED GRADIENT
ON SUN WILL RESULT IN NORTH TO NORTHWEST FLOW APPROACHING 25 KT AT
TIMES SUN INTO SUN NIGHT. HEADLINES WILL LIKELY BE REQUIRED THOUGH
SEAS MAY END UP REMAINING UNDER 6 FT GIVEN THE OFFSHORE TRAJECTORY.
COLD ADVECTION WEAKENS LATE SUN NIGHT AND GRADIENT RELAXES WITH
WINDS VEERING TO NORTHEAST AND DECREASING AS RIDGE AXIS MOVES CLOSER
TO THE COAST. LIGHT NORTHEAST FLOW WILL CONTINUE MON INTO TUE WITH
SURFACE HIGH RIDGING DOWN THE COAST. SPEEDS WILL DROP UNDER 10 KT BY
AFTERNOON WITH SEAS DROPPING TO 2 TO 3 FT. WEAK COASTAL TROUGH
DEVELOPS EARLY TUE WITH WINDS BECOMING VARIABLE ALONG THE TROUGH
AXIS. SOUTHEAST FLOW DEVELOPS OVER THE WATERS LATER TUE AND STARTS
TO INCREASE AS THE TROUGH MOVES CLOSER TO THE COAST. INCREASE IN
WINDS COMBINED WITH ONSHORE TRAJECTORY PUSHES SEAS TO 3 TO 4 FT BY
THE END OF THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 3 AM EST FRIDAY FOR AMZ250-252.
&&
$$
SYNOPSIS...MBB
NEAR TERM...DCH/TRA
SHORT TERM...MBB
LONG TERM...III
AVIATION...SGL/TRA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
909 PM EST SAT NOV 23 2013
.SYNOPSIS...
LAKE EFFECT SHOWERS WILL INITIATE IN THE WAKE OF THE COLD FRONT
TONIGHT. HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE EAST
ON SUNDAY AND PERSIST THROUGH MONDAY. A COLD FRONT WILL MOVE
ACROSS THE AREA LATE MONDAY NIGHT INTO TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
I WILL CONTINUE WITH THE CURRENT FORECAST TREND. THE HRRR MODEL
SEEMS TO BE HANDLING THE CURRENT LAKE EFFECT SITUATION WELL. IT
SHOWS TWO MAIN BANDS...ONE OVER NW PA AND ONE JUST EAST OF CLE.
THE RADAR SHOWS THIS TREND. THE MODEL SHOWS THE BAND EAST OF CLE
WEAKENING AFTER 06Z WITH THE BANDS OVER NW PA BECOMING DOMINATE.
THE WARNED AREA LOOKS GOOD. I AM A LITTLE UNEASY ABOUT
LAKE...GEAUGA...EASTERN CUYAHOGA AND THE NORTHERN SECTIONS OF
PORTAGE AND SUMMIT. CURRENT FORECAST OF 2 TO 4 INCHES LOOKS
REASONABLE BUT VALUES COULD CLIMB TO NEAR LAKE EFFECT ADVISORY
LEVELS IF THE BAND EAST OF CLEVELAND PERSISTS. I WILL CONTINUE
TO MONITOR BUT AN ADVISORY WILL NOT BE ISSUED WITH THIS UPDATE.
PREVIOUS DISCUSSION...
THE COLD FRONT IS CURRENTLY SOUTHEAST OF THE AREA. TEMPERATURES
WILL CONTINUE TO DROP STEADILY BEHIND THE FRONT DUE TO STRONG COLD
AIR ADVECTION. COLDER TEMPERATURES WILL LEAD TO EXTREME
INSTABILITY OVER LAKE ERIE...INITIATING LAKE EFFECT SNOW. THERE IS
STILL SOME QUESTION AS TO HOW STRONG THE LAKE EFFECT SNOW WILL
BECOME. 850 MB TEMPERATURES AROUND 25C WILL PROVIDE ENOUGH
INSTABILITY TO PRODUCE HEAVY SNOW...BUT MOISTURE WILL BE LIMITED
DUE TO SHORT FETCH WITH NORTHWEST WINDS. ONE WAY TO GET ADDED
MOISTURE IS FOR THE LAKE EFFECT TO DEVELOP A CONNECTION TO ANOTHER
LAKE. MODELS ARE HINTING AT A LAKE HURON CONNECTION WITH THIS
EVENT AND IF THAT OCCURS WE MAY GET THE ADDED MOISTURE NECESSARY
TO REALLY GET THINGS GOING.
SNOW ACCUMULATIONS ARE ALSO A BIT TRICKY AND DEPEND ON WHETHER OR
NOT WE GET THAT LAKE HURON CONNECTION. ASSUMING WE GET THE
CONNECTION...WE COULD SEE ANYWHERE FROM SIX INCHES TO OVER A FOOT
OF SNOW OVER EXTREME NORTHEAST OHIO AND NORTHWEST PENNSYLVANIA. THE
AREAS MOST LIKELY TO SEE OVER A FOOT OF SNOW ARE THE IN THE HIGHER
TERRAIN OF NORTHWEST PENNSYLVANIA WHERE UPSLOPE FLOW WILL ENHANCE
THE LAKE EFFECT SNOW. SEVERAL SECONDARY BANDS MAY DEVELOP TO THE
WEST OF THE PRIMARY BAND. THE SECONDARY BANDS DO NOT LOOK LIKE THEY
WILL PRODUCE ENOUGH SNOW TO REACH ADVISORY CRITERIA. THE EVENING
SHIFT WILL CONTINUE TO MONITOR THE SITUATION AS IT EVOLVES AND ISSUE
AN ADVISORY IF THEY BELIEVE IT TO BE NECESSARY.
AS FOR TEMPERATURES TONIGHT...COLD AIR ADVECTION WILL CONTINUE
OVERNIGHT WITH OVERNIGHT LOWS REACHING INTO THE TEENS FOR MANY
LOCATIONS.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
HIGH PRESSURE WILL MOVE EAST INTO THE AREA ON SUNDAY...HELPING TO
TAPER THE LAKE EFFECT SNOW SUNDAY EVENING. WE WILL GET A BRIEF
RESPITE FROM THE SNOW ON MONDAY AS THE HIGH PRESSURE SLIDES EAST.
A COLD FRONT WILL CROSS THE AREA LATE MONDAY NIGHT INTO TUESDAY
MORNING. NOT EXPECTING MUCH IN THE WAY OF SNOW WITH THE FRONTAL
PASSAGE. FOR NOW...GOING WITH A CHANCE OF SNOW SHOWERS FOR MOST OF
THE FORECAST AREA.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
COLD AND MAINLY QUIET WEATHER IS EXPECTED DURING THE LONG TERM
PERIOD. SOME LAKE EFFECT IS POSSIBLE TUESDAY NIGHT INTO WEDNESDAY
BUT WINDS QUICKLY BECOME UNFAVORABLE ON WEDNESDAY EVENING. IT
APPEARS THAT MOST OF THE LAKE EFFECT WILL BE NUISANCE TYPE
ACTIVITY AND AM NOT ANTICIPATING ANY HEADLINES. THURSDAY THROUGH
SATURDAY LOOK TO BE DRY. HIGH TEMPS DURING THE PERIOD WILL
CONTINUE TO BE 10 TO 15 DEGREES BELOW NORMAL.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
LAKE EFFECT SNOW SHOWERS IN THE WAKE OF THE COLD FRONT FROM
EARLIER TODAY WILL CONTINUE THROUGH THE NIGHT. FROM CLE/CAK AND
POINTS NORTHEAST WILL SEE VARIABLE CONDITIONS WITH THE PERIODIC
SNOW SHOWERS. THE WORST AND MOST PROLONGED CONDITIONS EXPECTED IN
THE VICINITY OF ERI AS SOME OF THE BEST LAKE EFFECT SNOW BANDS ARE
EXPECTED THERE...AND POSSIBLY A PROLONGED PERIOD OF IFR. IF AN
ORGANIZED BAND DOES TAKE SHAPE...MAY HAVE SOME LIGHTING WITH IT AS
LAKE INDUCED INSTABILITY IS QUITE UNSTABLE. OUTSIDE OF THE SNOW
SHOWERS LARGELY VFR. A FEW FLURRIES POSSIBLE AT MFD. WINDS WILL
CONTINUE TO GUST MOST OF THE NIGHT IN THE 20 TO 25 KNOT RANGE. THE
HIGH BUILDS IN ACROSS THE OHIO VALLEY FOR SUNDAY...SLOWLY TAPERING
THE SNOW SHOWERS AND SHUTTING DOWN THE LAKE EFFECT. THE SNOW WILL
LINGER THE LONGEST AT YNG AND ERI. BY SUNDAY AFTERNOON WINDS WILL
START TO DIMINISH AND BACK MORE WESTERLY.
OUTLOOK...NON VFR MAINLY OVER NE OH AND NW PA THROUGH SUNDAY
NIGHT BECAUSE OF LAKE EFFECT. MORE WIDESPREAD SYNOPTIC SNOW
EXPECTED LATE MONDAY NIGHT INTO TUESDAY AND CONTINUING ACROSS NE
OH/NW PA ON WEDNESDAY IN LAKE EFFECT SHSN...AND THEREFORE NON-VFR
CONDITIONS.
&&
.MARINE...
HAVE ISSUED THE GALE WARNING FOR THE CENTRAL AND EASTERN PORTIONS
OF LAKE ERIE. WINDS QUICKLY RAMPED UP ABOVE 30 KNOTS AND HAVE BEEN
GALE FORCE. THE OUTLOOK FOR THE REMAINDER OF THE NIGHT IS LOW END
GALES...DIMINISHING SUNDAY MORNING. THE FLOW WILL FINALLY BECOME
WEST SUNDAY EVENING AND THEN SW BY DAYBREAK MONDAY AS HIGH
PRESSURE BUILDS IN FROM THE SOUTH. SOUTHWEST FLOW IS EXPECTED TO
CONTINUE TILL ANOTHER COLD FRONT CROSSES THE LAKE ON TUESDAY. THIS
WILL BRING MORE CHANCES FOR PRECIP AND NW FLOW BACK TO THE LAKE.
WINDS WILL BECOME NORTHERLY ON WEDNESDAY AND NE ON THURSDAY S
ARCTIC HIGH PRESSURE BUILDS IN FROM THE NORTH.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...LAKE EFFECT SNOW WARNING UNTIL MIDNIGHT EST SUNDAY NIGHT FOR
OHZ014-089.
PA...LAKE EFFECT SNOW WARNING UNTIL MIDNIGHT EST SUNDAY NIGHT FOR
PAZ001>003.
MARINE...GALE WARNING UNTIL 4 AM EST SUNDAY FOR LEZ061-146>149-166>169.
SMALL CRAFT ADVISORY UNTIL 11 AM EST TUESDAY FOR LEZ142>145.
&&
$$
SYNOPSIS...SCHEPEL
NEAR TERM...GARNET
SHORT TERM...SCHEPEL
LONG TERM...KUBINA
AVIATION...OUDEMAN
MARINE...KUBINA/OUDEMAN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
649 PM EST SAT NOV 23 2013
.SYNOPSIS...
LAKE EFFECT SHOWERS WILL INITIATE IN THE WAKE OF THE COLD FRONT
TONIGHT. HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE EAST
ON SUNDAY AND PERSIST THROUGH MONDAY. A COLD FRONT WILL MOVE
ACROSS THE AREA LATE MONDAY NIGHT INTO TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
NO MAJOR CHANGES TO THE CURRENT FORECAST PACKAGE. I WILL MAKE
MINOR ADJUSTMENTS TO THE TEMPERATURES TO REFLECT CURRENT TRENDS.
I WILL CONTINUE TO MONITOR THE LAKE EFFECT SNOW AS IT DEVELOPS
THIS EVENING. THE HRRR MODEL KEEPS THE MOST SIGNIFICANT BAND OVER
NW PA AND ASHTABULA COUNTY. THE MODEL DOES HINT AT THE DEVELOPMENT
OF A SECONDARY BAND JUST EAST OF CLE.
PREVIOUS DISCUSSION...
THE COLD FRONT IS CURRENTLY SOUTHEAST OF THE AREA. TEMPERATURES
WILL CONTINUE TO DROP STEADILY BEHIND THE FRONT DUE TO STRONG COLD
AIR ADVECTION. COLDER TEMPERATURES WILL LEAD TO EXTREME
INSTABILITY OVER LAKE ERIE...INITIATING LAKE EFFECT SNOW. THERE IS
STILL SOME QUESTION AS TO HOW STRONG THE LAKE EFFECT SNOW WILL
BECOME. 850 MB TEMPERATURES AROUND 25C WILL PROVIDE ENOUGH
INSTABILITY TO PRODUCE HEAVY SNOW...BUT MOISTURE WILL BE LIMITED
DUE TO SHORT FETCH WITH NORTHWEST WINDS. ONE WAY TO GET ADDED
MOISTURE IS FOR THE LAKE EFFECT TO DEVELOP A CONNECTION TO ANOTHER
LAKE. MODELS ARE HINTING AT A LAKE HURON CONNECTION WITH THIS
EVENT AND IF THAT OCCURS WE MAY GET THE ADDED MOISTURE NECESSARY
TO REALLY GET THINGS GOING.
SNOW ACCUMULATIONS ARE ALSO A BIT TRICKY AND DEPEND ON WHETHER OR
NOT WE GET THAT LAKE HURON CONNECTION. ASSUMING WE GET THE
CONNECTION...WE COULD SEE ANYWHERE FROM SIX INCHES TO OVER A FOOT
OF SNOW OVER EXTREME NORTHEAST OHIO AND NORTHWEST PENNSYLVANIA. THE
AREAS MOST LIKELY TO SEE OVER A FOOT OF SNOW ARE THE IN THE HIGHER
TERRAIN OF NORTHWEST PENNSYLVANIA WHERE UPSLOPE FLOW WILL ENHANCE
THE LAKE EFFECT SNOW. SEVERAL SECONDARY BANDS MAY DEVELOP TO THE
WEST OF THE PRIMARY BAND. THE SECONDARY BANDS DO NOT LOOK LIKE THEY
WILL PRODUCE ENOUGH SNOW TO REACH ADVISORY CRITERIA. THE EVENING
SHIFT WILL CONTINUE TO MONITOR THE SITUATION AS IT EVOLVES AND ISSUE
AN ADVISORY IF THEY BELIEVE IT TO BE NECESSARY.
AS FOR TEMPERATURES TONIGHT...COLD AIR ADVECTION WILL CONTINUE
OVERNIGHT WITH OVERNIGHT LOWS REACHING INTO THE TEENS FOR MANY
LOCATIONS.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
HIGH PRESSURE WILL MOVE EAST INTO THE AREA ON SUNDAY...HELPING TO
TAPER THE LAKE EFFECT SNOW SUNDAY EVENING. WE WILL GET A BRIEF
RESPITE FROM THE SNOW ON MONDAY AS THE HIGH PRESSURE SLIDES EAST.
A COLD FRONT WILL CROSS THE AREA LATE MONDAY NIGHT INTO TUESDAY
MORNING. NOT EXPECTING MUCH IN THE WAY OF SNOW WITH THE FRONTAL
PASSAGE. FOR NOW...GOING WITH A CHANCE OF SNOW SHOWERS FOR MOST OF
THE FORECAST AREA.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
COLD AND MAINLY QUIET WEATHER IS EXPECTED DURING THE LONG TERM
PERIOD. SOME LAKE EFFECT IS POSSIBLE TUESDAY NIGHT INTO WEDNESDAY
BUT WINDS QUICKLY BECOME UNFAVORABLE ON WEDNESDAY EVENING. IT
APPEARS THAT MOST OF THE LAKE EFFECT WILL BE NUISANCE TYPE
ACTIVITY AND AM NOT ANTICIPATING ANY HEADLINES. THURSDAY THROUGH
SATURDAY LOOK TO BE DRY. HIGH TEMPS DURING THE PERIOD WILL
CONTINUE TO BE 10 TO 15 DEGREES BELOW NORMAL.
&&
.AVIATION /23Z SUNDAY THROUGH THURSDAY/...
LAKE EFFECT SNOW SHOWERS IN THE WAKE OF THE COLD FRONT FROM
EARLIER TODAY WILL CONTINUE THROUGH THE NIGHT. FROM CLE/CAK AND
POINTS NORTHEAST WILL SEE VARIABLE CONDITIONS WITH THE PERIODIC
SNOW SHOWERS. THE WORST AND MOST PROLONGED CONDITIONS EXPECTED IN
THE VICINITY OF ERI AS SOME OF THE BEST LAKE EFFECT SNOW BANDS ARE
EXPECTED THERE...AND POSSIBLY A PROLONGED PERIOD OF IFR. IF AN
ORGANIZED BAND DOES TAKE SHAPE...MAY HAVE SOME LIGHTING WITH IT AS
LAKE INDUCED INSTABILITY IS QUITE UNSTABLE. OUTSIDE OF THE SNOW
SHOWERS LARGELY VFR. A FEW FLURRIES POSSIBLE AT MFD. WINDS WILL
CONTINUE TO GUST MOST OF THE NIGHT IN THE 20 TO 25 KNOT RANGE. THE
HIGH BUILDS IN ACROSS THE OHIO VALLEY FOR SUNDAY...SLOWLY TAPERING
THE SNOW SHOWERS AND SHUTTING DOWN THE LAKE EFFECT. THE SNOW WILL
LINGER THE LONGEST AT YNG AND ERI. BY SUNDAY AFTERNOON WINDS WILL
START TO DIMINISH AND BACK MORE WESTERLY.
OUTLOOK...NON VFR MAINLY OVER NE OH AND NW PA THROUGH SUNDAY
NIGHT BECAUSE OF LAKE EFFECT. MORE WIDESPREAD SYNOPTIC SNOW
EXPECTED LATE MONDAY NIGHT INTO TUESDAY AND CONTINUING ACROSS NE
OH/NW PA ON WEDNESDAY IN LAKE EFFECT SHSN...AND THEREFORE NON-VFR
CONDITIONS.
&&
.MARINE...
HAVE ISSUED THE GALE WARNING FOR THE CENTRAL AND EASTERN PORTIONS
OF LAKE ERIE. WINDS QUICKLY RAMPED UP ABOVE 30 KNOTS AND HAVE BEEN
GALE FORCE. THE OUTLOOK FOR THE REMAINDER OF THE NIGHT IS LOW END
GALES...DIMINISHING SUNDAY MORNING. THE FLOW WILL FINALLY BECOME
WEST SUNDAY EVENING AND THEN SW BY DAYBREAK MONDAY AS HIGH
PRESSURE BUILDS IN FROM THE SOUTH. SOUTHWEST FLOW IS EXPECTED TO
CONTINUE TILL ANOTHER COLD FRONT CROSSES THE LAKE ON TUESDAY. THIS
WILL BRING MORE CHANCES FOR PRECIP AND NW FLOW BACK TO THE LAKE.
WINDS WILL BECOME NORTHERLY ON WEDNESDAY AND NE ON THURSDAY S
ARCTIC HIGH PRESSURE BUILDS IN FROM THE NORTH.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...LAKE EFFECT SNOW WARNING UNTIL MIDNIGHT EST SUNDAY NIGHT FOR
OHZ014-089.
PA...LAKE EFFECT SNOW WARNING UNTIL MIDNIGHT EST SUNDAY NIGHT FOR
PAZ001>003.
MARINE...GALE WARNING UNTIL 4 AM EST SUNDAY FOR LEZ061-146>149-166>169.
SMALL CRAFT ADVISORY UNTIL 11 AM EST TUESDAY FOR LEZ142>145.
&&
$$
SYNOPSIS...SCHEPEL
NEAR TERM...GARNET
SHORT TERM...SCHEPEL
LONG TERM...KUBINA
AVIATION...OUDEMAN
MARINE...KUBINA/OUDEMAN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
610 PM EST SAT NOV 23 2013
.SYNOPSIS...
LAKE EFFECT SHOWERS WILL INITIATE IN THE WAKE OF THE COLD FRONT
TONIGHT. HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE EAST
ON SUNDAY AND PERSIST THROUGH MONDAY. A COLD FRONT WILL MOVE
ACROSS THE AREA LATE MONDAY NIGHT INTO TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
NO MAJOR CHANGES TO THE CURRENT FORECAST PACKAGE. I WILL MAKE
MINOR ADJUSTMENTS TO THE TEMPERATURES TO REFLECT CURRENT TRENDS.
I WILL CONTINUE TO MONITOR THE LAKE EFFECT SNOW AS IT DEVELOPS
THIS EVENING. THE HRRR MODEL KEEPS THE MOST SIGNIFICANT BAND OVER
NW PA AND ASHTABULA COUNTY. THE MODEL DOES HINT AT THE DEVELOPMENT
OF A SECONDARY BAND JUST EAST OF CLE.
PREVIOUS DISCUSSION...
THE COLD FRONT IS CURRENTLY SOUTHEAST OF THE AREA. TEMPERATURES
WILL CONTINUE TO DROP STEADILY BEHIND THE FRONT DUE TO STRONG COLD
AIR ADVECTION. COLDER TEMPERATURES WILL LEAD TO EXTREME
INSTABILITY OVER LAKE ERIE...INITIATING LAKE EFFECT SNOW. THERE IS
STILL SOME QUESTION AS TO HOW STRONG THE LAKE EFFECT SNOW WILL
BECOME. 850 MB TEMPERATURES AROUND 25C WILL PROVIDE ENOUGH
INSTABILITY TO PRODUCE HEAVY SNOW...BUT MOISTURE WILL BE LIMITED
DUE TO SHORT FETCH WITH NORTHWEST WINDS. ONE WAY TO GET ADDED
MOISTURE IS FOR THE LAKE EFFECT TO DEVELOP A CONNECTION TO ANOTHER
LAKE. MODELS ARE HINTING AT A LAKE HURON CONNECTION WITH THIS
EVENT AND IF THAT OCCURS WE MAY GET THE ADDED MOISTURE NECESSARY
TO REALLY GET THINGS GOING.
SNOW ACCUMULATIONS ARE ALSO A BIT TRICKY AND DEPEND ON WHETHER OR
NOT WE GET THAT LAKE HURON CONNECTION. ASSUMING WE GET THE
CONNECTION...WE COULD SEE ANYWHERE FROM SIX INCHES TO OVER A FOOT
OF SNOW OVER EXTREME NORTHEAST OHIO AND NORTHWEST PENNSYLVANIA. THE
AREAS MOST LIKELY TO SEE OVER A FOOT OF SNOW ARE THE IN THE HIGHER
TERRAIN OF NORTHWEST PENNSYLVANIA WHERE UPSLOPE FLOW WILL ENHANCE
THE LAKE EFFECT SNOW. SEVERAL SECONDARY BANDS MAY DEVELOP TO THE
WEST OF THE PRIMARY BAND. THE SECONDARY BANDS DO NOT LOOK LIKE THEY
WILL PRODUCE ENOUGH SNOW TO REACH ADVISORY CRITERIA. THE EVENING
SHIFT WILL CONTINUE TO MONITOR THE SITUATION AS IT EVOLVES AND ISSUE
AN ADVISORY IF THEY BELIEVE IT TO BE NECESSARY.
AS FOR TEMPERATURES TONIGHT...COLD AIR ADVECTION WILL CONTINUE
OVERNIGHT WITH OVERNIGHT LOWS REACHING INTO THE TEENS FOR MANY
LOCATIONS.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
HIGH PRESSURE WILL MOVE EAST INTO THE AREA ON SUNDAY...HELPING TO
TAPER THE LAKE EFFECT SNOW SUNDAY EVENING. WE WILL GET A BRIEF
RESPITE FROM THE SNOW ON MONDAY AS THE HIGH PRESSURE SLIDES EAST.
A COLD FRONT WILL CROSS THE AREA LATE MONDAY NIGHT INTO TUESDAY
MORNING. NOT EXPECTING MUCH IN THE WAY OF SNOW WITH THE FRONTAL
PASSAGE. FOR NOW...GOING WITH A CHANCE OF SNOW SHOWERS FOR MOST OF
THE FORECAST AREA.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
COLD AND MAINLY QUIET WEATHER IS EXPECTED DURING THE LONG TERM
PERIOD. SOME LAKE EFFECT IS POSSIBLE TUESDAY NIGHT INTO WEDNESDAY
BUT WINDS QUICKLY BECOME UNFAVORABLE ON WEDNESDAY EVENING. IT
APPEARS THAT MOST OF THE LAKE EFFECT WILL BE NUISANCE TYPE
ACTIVITY AND AM NOT ANTICIPATING ANY HEADLINES. THURSDAY THROUGH
SATURDAY LOOK TO BE DRY. HIGH TEMPS DURING THE PERIOD WILL
CONTINUE TO BE 10 TO 15 DEGREES BELOW NORMAL.
&&
.AVIATION /23Z SATURDAY THROUGH THURSDAY/...
THE COLD FRONT CONTINUES TO MOVE EAST ACROSS THE AREA. A LINE OF
SNOW SHOWERS HAS DEVELOPED NEAR THE FRONT AND WILL AFFECT THE
EASTERN TAF SITES THE NEXT COUPLE OF HOURS. A BRIEF PERIOD OF IFR
VSBYS IS LIKELY. CIGS ARE EXPECTED TO DIP TO MVFR LATER THIS
AFTERNOON. IN THE WEST...THESE LOWER CIGS WILL BE HIT AND MISS BUT
IN THE EAST FAIRLY WIDESPREAD. LAKE EFFECT SHSN WILL GET GOING
THIS EVENING AND HAVE HIT SNOW PRETTY HARD AT KERI. A PROLONGED
PERIOD OF IFR VSBYS COULD OCCUR. DRIER AIR WILL ARRIVE OVERNIGHT
AND EXPECT WESTERN AREAS TO CLEAR BACK OUT. BY 12Z SUNDAY THE SNOW
SHOWERS SHOULD ALL BE EAST OF KCLE. NW WINDS WILL GUST TO 30 KNOTS
THROUGH 00Z AND THEN ONLY SLOWLY DIMINISH OVERNIGHT.
OUTLOOK...NON VFR MAINLY OVER NE OH AND NW PA THROUGH SUNDAY
BECAUSE OF LAKE EFFECT. MORE WIDESPREAD SYNOPTIC SNOW EXPECTED
LATE MONDAY NIGHT INTO TUESDAY AND CONTINUING ACROSS NE OH/NW PA
ON WEDNESDAY IN LAKE EFFECT SHSN.
&&
.MARINE...
NO CHANGES TO THE SMALL CRAFT HEADLINES. WINDS ARE ALREADY GUSTING
TO AROUND 30 KNOTS BUT DO NOT THINK THEY SHOULD GET ANY STRONGER SO
WILL NOT GO WITH A GALE. WINDS WILL REMAIN UP MUCH OF THE NIGHT AND
ONLY SLOWLY DIMINISH ON SUNDAY. THE FLOW WILL FINALLY BECOME WEST
TOMORROW EVENING AND THEN SW BY DAYBREAK MONDAY AS HIGH PRESSURE
BUILDS IN FROM THE SOUTH. SOUTHWEST FLOW IS EXPECTED TO CONTINUE
TILL ANOTHER COLD FRONT CROSSES THE LAKE ON TUESDAY. THIS WILL
BRING MORE CHANCES FOR PRECIP AND NW FLOW BACK TO THE LAKE. WINDS
WILL BECOME NORTHERLY ON WEDNESDAY AND NE ON THURSDAY S ARCTIC HIGH
PRESSURE BUILDS IN FROM THE NORTH.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...LAKE EFFECT SNOW WARNING UNTIL MIDNIGHT EST SUNDAY NIGHT FOR
OHZ014-089.
PA...LAKE EFFECT SNOW WARNING UNTIL MIDNIGHT EST SUNDAY NIGHT FOR
PAZ001>003.
MARINE...GALE WARNING UNTIL 4 AM EST SUNDAY FOR LEZ061-146>149-166>169.
SMALL CRAFT ADVISORY UNTIL 11 AM EST TUESDAY FOR LEZ142>145.
&&
$$
SYNOPSIS...SCHEPEL
NEAR TERM...GARNET
SHORT TERM...SCHEPEL
LONG TERM...KUBINA
AVIATION...KUBINA
MARINE...KUBINA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1233 PM EST FRI NOV 22 2013
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE AREA TODAY. THIS WILL BE FOLLOWED
BY AN ARCTIC FRONT ON SATURDAY...WHICH WILL USHER IN MUCH COLDER
CONDITIONS AND PRODUCE LAKE EFFECT SNOW IN THE SNOWBELT SATURDAY
NIGHT INTO SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHOWERS MOSTLY CONFINED TO THE EASTERN HALF OF THE FORECAST AREA
AT THIS TIME AS DRIER AIR ARRIVES BEHIND THE FRONT. THE HRRR SHOWS
A BAND OF LIGHT SHOWERS RE-DEVELOPING THIS AFTERNOON ACROSS LAKE
ERIE AND NRN OHIO AS THE 850MB TROUGH SWINGS THROUGH. THERE IS
ALREADY SOME SUPPORT OF THIS SHOWING UP ON REGIONAL RADARS AND
WILL HOLD ONTO A LOW CHANCE OF SHOWERS...ALTHOUGH EXPECTED TO BE
BRIEF. NORTHWEST WINDS WILL INCREASE BEHIND THE FRONT THIS
AFTERNOON TO 10 TO 20 MPH IN THE WEST.
PREVIOUS DISCUSSION...
THE KILN SOUNDING THIS MORNING SHOWED DEEP MOISTURE IN
PLACE OVER THE REGION THROUGH 550MB. SHOWERS ARE FILLING IN ON THE
RADAR AS MOISTURE CONTINUES TO STREAM NORTHWARD IN ADVANCE OF THE
STRONG FRONT APPROACHING FROM THE NORTHWEST. RAISED POPS TO NEAR
100 PERCENT AS THIS WILL BE THE TREND FOR THE NEXT SEVERAL HOURS
EXCEPT FOR EXTREME NW OHIO WHERE DRIER AIR IS ALREADY SNEAKING IN
FROM THE WEST. HIGHS WILL OCCUR THIS MORNING WITH TEMPERATURES
SLOWLY FALLING BEHIND THE FRONT. WILL KEEP PRECIP TYPE AS ALL RAIN
AS WE LOSE OUR MOISTURE ALOFT BY THE TIME THE BOUNDARY LAYER COOLS
ENOUGH FOR SNOW.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
FRONT SHOULD BE WELL SOUTH OF THE AREA BY THIS EVENING TAKING THE
RAIN WITH IT. EXPECT DRY SLOT FOR TONIGHT INTO SATURDAY UNTIL
ARCTIC FRONT PUSHES THROUGH BY EARLY AFTERNOON. EXPECT SOME LIGHT
SNOW WITH THE FRONT...THEN A LULL BEFORE THE LAKE EFFECT SNOW
SHOWERS KICK IN. TEMPERATURES ON SATURDAY WILL PEAK BY LATE MORNING
WITH STEADY OR FALLING TEMPS IN THE AFTERNOON.
COLDEST AIR MOVES OVER THE LAKE SATURDAY NIGHT AS MODELS CONTINUE
PLUNGING THE 850MB TEMPS TO MINUS 18C BY SUNDAY MORNING. WATCH
OVER NW PA AND ASHTABULA COUNTY OHIO CONTINUES. SEVERAL INGREDIENTS
ADDING TO POTENTIAL FOR WARNING IN WATCH AREA. MODERATE INSTABILITY
OVER THE LAKE. IN ADDITION MODELS HAVE BEEN CONSISTENT WITH NW FLOW
SETTING UP AND CONTINUING INTO SUNDAY AFTERNOON. DEFINITE POTENTIAL
FOR A HURON CONNECTION SETTING UP WHICH COULD LAST INTO SUNDAY. THAT
COMBINED WITH THE HIGHER TERRAIN AWAY FROM THE LAKESHORE ALL POINT
TO THE POTENTIAL OF 6 TO 10 INCHES ACROSS THE HIGHER TERRAIN.
STILL SOME DOUBT IN MY MIND...HOW LONG WILL IT TAKE FOR THE LAKE
EFFECT TO START AFTER ARCTIC FRONT...AND THE DEPTH OF THE SYNOPTIC
MOISTURE. FOR NOW LOOKS LIKE LAKE EFFECT SNOW WILL CONTINUE INTO
SUNDAY AFTERNOON...WHEN SURFACE RIDGING FINALLY FORCES WINDS TO THE
SOUTHWEST.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
A COLD FRONT WILL CROSS THE AREA TUESDAY...MOISTURE IS OK...SO
EXPANDING THE CHANCE POPS TO MOST OF THE FORECAST AREA. AN
ONSHORE...MAINLY NORTHERLY FLOW WILL DEVELOP TUESDAY NIGHT AND
CONTINUE INTO THURSDAY. MOISTURE IS LIMITED...IT IS COLD...THE LAKE
AND 850 MB TEMPERATURE DIFFERENCE WILL BE OVER 20C AT TIMES. FOR THE
TIME BEING JUST KEPT CHANCE POPS OVER THE EASTERN HALF OF THE
FORECAST AREA. A RIDGE WILL BEGIN BUILDING IN BY LATE THURSDAY AND
ANY LAKE EFFECT SNOW SHOWERS WILL BE ENDING THURSDAY NIGHT AS THE
FLOW BECOMES SOUTHWEST. USED A BLEND OF GUIDANCE FOR THE
TEMPERATURES.
&&
.AVIATION /17Z FRIDAY THROUGH TUESDAY/...
A SLOW IMPROVEMENT IN CONDITIONS CONTINUES IN THE WEST WHERE VSBYS
HAVE IMPROVED AND CIGS HAVE JUMPED TO MVFR. EXPECT THIS TREND TO
CONTINUE TO THE EAST THIS AFTERNOON AS THE COLD FRONT EXITS THE
AREA. EXPECT ALL BUT THE FAR EASTERN END OF THE AREA TO HAVE MVFR
CIGS BY SUNSET. A CLEARING LINE OVER THE WESTERN GREAT LAKES WILL
REACH WESTERN AREAS THIS EVENING. EVEN IN THE EAST CONDITIONS
SHOULD BECOME VFR THIS EVENING. EXPECT ABOUT THE SW 2/3 OF THE
AREA TO LOSE CIGS OVERNIGHT WHILE LAKE CLOUDS REMAIN FROM KCLE
EAST TO KYNG AND UP THE LAKE TO NW PA. WEST FLOW WILL BECOME NW
THIS AFTERNOON AND SOME GUSTS TO 20 KNOTS ARE LIKELY INTO THE
EVENING HOURS. VFR WEATHER IS EXPECTED THE SECOND HALF OF THE
PERIOD.
OUTLOOK...NON VFR MAINLY OVER NE OH AND NW PA SATURDAY THROUGH
SUNDAY BECAUSE OF LAKE EFFECT. NON VFR RETURNING LATE MONDAY
NIGHT INTO TUESDAY.
&&
.MARINE...
AN ACTIVE WEATHER PATTERN FOR THE LAKE...TODAY THROUGH LATE NEXT
WEEK.
A COLD FRONT WILL MOVE ACROSS THE LAKE THIS MORNING AND CONDITIONS
SHOULD REACH SMALL CRAFT ADVISORY CRITERIA BY LATE AFTERNOON...THUS
A SMALL CRAFT ADVISORY WILL BE IN EFFECT STARTING AT 4 PM. THERE
COULD BE A PERIOD OF SEVERAL HOURS AROUND DAYBREAK SATURDAY WHEN WE
WILL BE BELOW SMALL CRAFT ADVISORY CRITERIA BUT THEN THE ARCTIC
FRONT MOVES THROUGH SATURDAY MORNING. THUS THE SMALL CRAFT ADVISORY
IS IN EFFECT THROUGH SUNDAY EVENING. AT THIS TIME IT DOESN`T LOOK
LIKE WILL WE MAKE GALES. WE WILL JUST BE BELOW THE GALE CRITERIA.
THE WINDS ALOFT JUST AREN`T STRONG ENOUGH AND THE COLD ADVECTION IS
SOMEWHAT GRADUAL.
HIGH PRESSURE WILL PASS TO THE SOUTH OF THE LAKE SUNDAY NIGHT
SHIFTING THE WINDS TO THE SOUTHWEST. THE WINDS WILL BE ON THE STRONG
SIDE...SO IT IS POSSIBLE A SMALL CRAFT ADVISORY COULD BE NEEDED ON
THE EAST END. A COLD FRONT WILL CROSS THE LAKE LATE TUESDAY AND A
SMALL CRAFT ADVISORY COULD BE NEEDED ON THE ENTIRE NEARSHORE TUESDAY
NIGHT INTO EARLY THURSDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...LAKE EFFECT SNOW WATCH FROM SATURDAY EVENING THROUGH SUNDAY
EVENING FOR OHZ014-089.
PA...LAKE EFFECT SNOW WATCH FROM SATURDAY EVENING THROUGH SUNDAY
EVENING FOR PAZ001>003.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST
SUNDAY FOR LEZ142>149.
&&
$$
SYNOPSIS...DJB
NEAR TERM...KEC
SHORT TERM...DJB
LONG TERM...KIELTYKA
AVIATION...KUBINA
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS NORMAN OK
300 PM CST FRI NOV 22 2013
.DISCUSSION...
TWO MAIN FORECAST CONCERNS TO COVER...-FZRA/SLEET TODAY AND
SNOW/SLEET CHANCES LATE SATURDAY THROUGH MONDAY.
CURRENTLY...ACTIVE WINTER WEATHER CONTINUES TO IMPACT MUCH OF
OKLAHOMA AND NRN TEXAS. FREEZING RAIN AND SLEET CONTINUE TO FALL
ACROSS PORTIONS OF WRN N TX AND THROUGH WRN AND CENTRAL OK THIS
AFTERNOON...THE IMPACTS OF WHICH HAVE PROMPTED A FEW TO SAY...WELL
THAT ESCALATED QUICKLY. WITH SFC TEMPS HOLDING AT OR NEAR
FREEZING...ROADS HAVE BECOME HAZARDOUS IN SOME PLACES ACROSS THE
REGION...WITH NUMEROUS TRAFFIC ACCIDENTS REPORTED VIA SOCIAL
MEDIA/LOCAL MEDIA/AND SPOTTERS. MOST ROADS REMAIN WET...NOT
FROZEN...WITH ELEVATED SURFACES...SUCH AS BRIDGES AND OVERPASSES THE
MOST LIKELY TO HAVE ICING. BEST ADVICE...SLOW DOWN. 18Z SPECIAL
RELEASE FROM OUN SHOWS A DECENT SLEET/FZRA SOUNDING...WITH BOTH
PRECIP TYPES FALLING AT VARIOUS TIMES AT THE OFFICE AND ACROSS THE
OKC METRO/REGION THROUGH THE PAST FEW HOURS. MOST IMPRESSIVE...THE
NEAR SFC FREEZING LAYER HAS REMAINED AS DEEP...-7 C AT BOTH 12 AND
18Z APPROXIMATELY 430M AGL. MESOSCALE MODELS...SUCH AS THE HRRR AND
RAP SEEM TO HAVE A DECENT HANDLE ON THE OVERALL PROGRESSION OF THE
SYSTEM. STARTING THIS MORNING...700MB WINDS BEGAN TO VEER BACK TO
THE SW...WITH GOOD WAA AND MOISTURE RETURN. WITH THE GOOD ISENTROPIC
RESPONSE...WELL VISUALIZED AT THE 305K LEVEL...ABOUT THE HEIGHT OF
THE 750-700MB LEVEL...FZRA AND SLEET WILL CONTINUE THROUGH THE
AFTN/EARLY EVENING HRS...SLOWLY SHIFTING S/SE THROUGH 00Z AS THE
ARCTIC HIGH CONTINUES TO PROTRUDE INTO NRN OK. AREAS OF -FZRA/-FZDZ
WILL LIKELY LINGER ACROSS CENTRAL OK THROUGH MIDNIGHT...WITH THE
REMAINDER OF ACTIVITY CONTINUING TO SHIFT SOUTHWARD THROUGH EARLY
SATURDAY MORNING...WITH AREAS OF -FZRA/-FZDZ/-RA NEAR/ALONG THE RED
RIVER VALLEY THROUGH SUNRISE.
SATURDAY DURING THE DAY SHOULD BE DRY...BUT COLD...WITH HIGHS ONLY
CLIMBING INTO THE MID/UPPER 30S...WITH WIND CHILLS IN THE TEENS AS
NORTH WINDS PERSIST. WINTER WEATHER WILL THEN MAKE A RETURN LATE
SATURDAY NIGHT AND CONTINUE THROUGH MONDAY. A DEEPENING UPPER
LOW...A BOWLING BALL IF YOU WILL...CONTINUES TO DIG DOWN THE WEST
COAST THIS AFTERNOON...WELL VISUALIZED ON WV IMAGERY. THIS
DEEPENING H500 TROUGH WILL CONTINUE TO DIG S/SE AND SWING EWRD
ACROSS THE DESERT SOUTHWEST. AS KG MENTIONED LAST NIGHT...THERE IS
NO APPARENT KICKER TO FORCE THIS FEATURE QUICKLY ACROSS THE SRN
PLAINS...SO ITS A RELATIVELY SLOW MOVING...BUT STRONG TROUGH.
GUIDANCE REMAINS IN DECENT AGREEMENT WITH THE TRANSITION OF THE
UPPER TROUGH...WITH A DECENT REGION OF ISENTROPIC LIFT DEVELOPING
ACROSS THE PANHANDLES AND FAR WRN OK SATURDAY NIGHT. GFS AND NAM
BUFR PROFILES TAKEN ACROSS THE REGION CONTINUE TO SHOW A SNOW/SLEET
MIX TO START...WITH A TRANSITION TO SNOW THROUGH SUNDAY...SPREADING
EASTWARD ACROSS THE REGION. GIVEN IT IS WINTER IN THE SRN
PLAINS...TIMING AND IMPACTS ARE LIKELY TO CHANGE BETWEEN NOW AND
THEN. HOWEVER...CONFIDENCE IS GROWING IN MUCH OF WRN N TX AND
CENTRAL AND WRN OK TO SEE THERE FIRST SNOW FLAKES OF THE YEAR. BEST
CHANCES WILL BE FROM WRN N TX THROUGH CENTRAL OK...WITH MOST
LOCATIONS SEEING A TRACE TO 2 INCHES...WITH SOME SEEING AS MUCH AS
3. OF COURSE...SOME LOCATIONS MAY SEE MORE SLEET THAN SNOW. LIGHT
SNOW/SLEET CHANCES WILL CONTINUE THROUGH MONDAY...WITH A TRANSITION
TO RAIN/SNOW MIX POSSIBLE...AND RAIN ACROSS SRN OK/NRN TX THROUGH
TUESDAY MORNING.
DRY...CALM WEATHER WILL THEN PERSIST FOR THE REMAINDER OF THE
HOLIDAY WEEK...WITH HIGHS WARMING BACK INTO THE LOWER 50S BY
THANKSGIVING DAY...CONTINUING THROUGH THE WEEKEND.
JTK
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 29 38 26 32 / 40 10 20 50
HOBART OK 27 38 26 31 / 30 10 30 50
WICHITA FALLS TX 30 39 28 34 / 50 10 30 70
GAGE OK 21 34 21 30 / 30 0 30 50
PONCA CITY OK 28 37 20 34 / 20 0 10 30
DURANT OK 34 42 31 38 / 60 20 10 60
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR OKZ004>047-
050-051.
TX...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR TXZ083>090.
&&
$$
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
935 AM EST FRI NOV 22 2013
.DISCUSSION...SPOTTY PATCHES OF LIGHT RAIN MOVING ACROSS THE
FORECAST AREA WELL AHEAD OF THE MORE SIGNIFICANT SHOWERS CLOSER TO
THE COLD FRONT. LATEST RUC MODEL RUN ADVANCES THE SHOWERS ACROSS THE
PLATEAU AND INTO SE TN BY NOON...THEN THE SHOWERS SPREAD TO THE FAR
ERN COUNTIES OF E TN AND SW VA BY MID TO LATE AFTERNOON. FORECAST
GRIDS COVER THIS SCENARIO QUITE WELL.
12Z SOUNDINGS FROM OHX AND RNK ARE WARM ALOFT WITH OHX SOUNDING
SATURATED FROM SURFACE TO 600 MBS. BETTER UPPER LEVEL SUPPORT IS TO
OUR NORTH...SO EXPECTING JUST SHOWERS (NO THUNDERSTORMS) AHEAD OF
THE FRONT.
PLAN TO FRESHEN THE HOURLY GRIDS AND DROP ANY MORNING WORDING FROM
THE ZFPMRX PRODUCT AROUND 11 AM EST.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 63 49 56 28 40 / 90 90 50 0 0
KNOXVILLE AIRPORT, TN 63 48 55 25 37 / 90 90 50 0 0
OAK RIDGE, TN 63 47 53 25 37 / 90 90 40 0 0
TRI CITIES AIRPORT, TN 63 45 52 22 33 / 90 90 50 0 0
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
TG
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1113 AM CST FRI NOV 22 2013
.DISCUSSION...
SEE AVIATION FOR 18Z TAF ISSUANCE.
&&
.AVIATION...
IFR CONDITIONS ACROSS THE AREA TODAY WITH THE SURFACE COLD FRONT
JUST MAKING IT TO KGLS. THERE IS A LINE OF THUNDERSTORMS CROSSING
KLBX AND APPROACHING KGLS. IN THESE THUNDERSTORMS EXPECT GUSTY
WINDS AND HEAVY RAIN. BEHIND THE MAIN LINE OF STORMS WE ARE
GETTING SOME REDEVELOPMENT OF LIGHT SHOWERS. THESE LIGHT TO
MODERATE SHOWERS WILL BE POSSIBLE THROUGH THE DAY INTO SATURDAY
MORNING AS THE 850MB FRONT TRIES TO MAKE IT DOWN INTO THE AREA.
BEST CHANCE OF THESE LIGHTER SHOWERS SEEMS TO TOWARDS THE NORTH.
CAN`T RULE IT OUT ACROSS THE ENTIRE AREA THOUGH. 23
&&
.PREV DISCUSSION... /ISSUED 949 AM CST FRI NOV 22 2013/
DISCUSSION...
STRONG COLD FRONT WILL CONTINUE TO MOVE OFF THE COAST THIS MORNING AND
ACROSS THE COASTAL WATERS THIS AFTERNOON. BEHIND THE FRONT...SEEING
SOME 1 TO 2 INCH RAINFALL TOTALS ACROSS THE HOUSTON AREA ON THE HARRIS
COUNTY FLOOD WARNING SYSTEM WEBSITE AS A BAND OF SHOWERS AND THUNDERSTORMS
MOVES ACROSS THE AREA. TEMPERATURES BEHIND THE FRONT HAVE FALLEN INTO
THE 40S AND 50S...AND DO NOT EXPECT TO SEE ANY WARMUP FOR THE REMAINDER
OF THE DAY. CURRENT FORECAST AND DISCUSSIONS BELOW ARE RIGHT ON TRACK...AND
AT THIS TIME WILL NOT ISSUE A MORNING UPDATE. 42
PREV DISCUSSION... /ISSUED 609 AM CST FRI NOV 22 2013/
DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION
AVIATION...
A STRONG COLD FRONT IS MOVING ACROSS SOUTHEAST TEXAS THIS MORNING
AND WILL APPROACH IAH WITHIN THE NEXT HOUR. THE FRONT IS MAKING A
QUICKER PUSH THROUGH OUR WESTERN COUNTIES SO THE BOUNDARY MAY
LIKELY MAKE IT THROUGH SGR BEFORE HOU AND WILL CLEAR MATAGORDA BAY
BEFORE MOVING THROUGH GLS. EXPECT SCATTERED SHOWERS AND
THUNDERSTORMS WITH THE FRONTAL PASSAGE AND THEN LINGERING LIGHT
RAIN AND IFR CIGS PERSISTING THROUGH THE TAF PERIOD. 38
PREV DISCUSSION... /ISSUED 451 AM CST FRI NOV 22 2013/
DISCUSSION...
THE COLD FRONT HAS PUSHED INTO SE TX THIS MORNING AND BASICALLY
LOCATED FROM BRENHAM TO HUNTSVILLE TO JUST WEST OF NACOGDOCHES.
TEMPS AT COLLEGE STATION HAVE DROPPED FROM LOW 70S TO LOW 50S IN
AN HOUR AND NOW HOVERING AROUND 50F. FRONT HAS JUST PUSHED THROUGH
HUNTSVILLE SO EXPECT A SIMILAR DROP IN TEMPS THE NEXT HOUR OR TWO.
MAIN CONCERN TODAY WILL BE THE FRONTAL PASSAGE AND TEMPS DROPPING
BEHIND IT. THE 06Z HRRR SEEMS TO BE ABOUT AN HOUR SLOW WITH THE
FRONT. WITH THAT IN MIND...THINK FRONT REACHES KCXO AROUND 12Z AND
THEN KIAH AROUND 14-15Z. FRONT MAY REACH MATAGORDA BAY AROUND
16-17Z WHICH IS ABOUT THE SAME TIME IT SHOULD PUSH THROUGH KHOU.
FRONT WILL SLOWLY PUSH OFF THE COAST AROUND 18Z. TEMPS SHOULD DROP
BEHIND THE FRONT THROUGH THE AFTERNOON. TEMPS CLOSELY FOLLOW
RECENT RAP/NAM RUNS WHICH ALSO SEEM TO HAVE A GOOD HANDLE ON THE
FRONT AND POST FRONTAL TEMPS. THIS MEANS THAT TEMPS WILL BE IN THE
40S FOR THE COLLEGE STATION AREA DURING THE AFTERNOON WITH 50S FOR
HOUSTON AREA. TEMPS WILL DROP QUICKLY INTO THE 40S OVERNIGHT.
THUNDERSTORM CHANCES HAVE BEEN KEPT HIGH AROUND 70/80 PERCENT AND
THEN HIGHER BEHIND THE FRONT FOR POST FRONTAL RAIN. WILL KEEP SOME
RAIN CHANCES GOING FRI NIGHT INTO SAT AS A WEAK VORTICITY MAX
MOVES OVER THE AREA AND FRONTOGENESIS FROM 850MB FRONT INCREASES.
DEEPER COLD AIR MOVES INTO THE AREA SAT NIGHT INTO SUN AND
BOUNDARY LAYER ALSO DRIES OUT BASED ON MODEL SOUNDINGS. HAVE LOWER
POPS FROM NE TO SW FOR SAT NIGHT AND SUN. SUNDAY EXPECT A STRONGER
VORTICITY MAX TO MOVE OVER THE AREA WHICH WILL BE IN ADVANCE OF
MAIN UPPER LEVEL LOW OVER THE DESERT SW. UPPER LOW WILL SLOWLY
MOVE ACROSS THE S ROCKIES SUN NIGHT INTO MON. IN RESPONSE...EXPECT
INCREASES ISENTROPIC LIFT EVIDENT AT 290K/295K SURFACES. SO RAIN
CHANCES WILL BE ON THE INCREASE SUN NIGHT INTO MON. INCREASED POPS
TO 70 PERCENT ON MONDAY BUT COULD VERY WELL HAVE GONE HIGHER.
DECIDED TO WAIT FOR A COUPLE MORE RUNS BUT EVERYTHING POINTS TO A
VERY WET MONDAY. COULD SEE 1-2 INCHES OF RAIN AREAWIDE FOR SE TX
FOR MONDAY. MOISTURE WILL BE STREAMING OVER THE FRONTAL SURFACE
FOR LIFT AS WELL AS INCREASED OMEGA AS THE UPPER LOW MOVES INTO
TX. LARGE SCALE ASCENT WILL NOT BE LACKING ON MONDAY AND WILL
PERSIST INTO MON NIGHT. THE HARDEST DETAILS WILL BE TO DETERMINE
EXACTLY WHERE/HOW RAIN BANDS SET UP. ALSO NOTE THAT THE BOUNDARY
LAYER WILL BE QUITE COLD UNDER THE FRONTAL SURFACE. NAM/GFS MODEL
SOUNDINGS WILL BE QUITE BORDERLINE FOR RAIN/FREEZING RAIN FROM
KCLL TO KLFK. NOT GOING TO GO WITH FROZEN PRECIP YET AS THINK SFC
WILL STAY WARM ENOUGH AND THERE IS A SOLID WARM NOSE OF 5-8C
THROUGH A 8000FT LAYER BETWEEN 925-700MB.
THERE ARE STILL SOME TIMING DIFFERENCES BETWEEN THE
NAM/GFS/ECMWF. NAM/ECMWF SOLUTIONS ARE A BIT FASTER WITH TAKING
THE COASTAL LOW FROM THE NW GULF INTO LA COAST. THEY ALSO BRING
THE SFC LOW CLOSER TO THE UPPER TX COAST WHICH WOULD ONLY ADD TO
RAINFALL POTENTIAL. GFS IS ABOUT 6 HRS SLOWER AND FARTHER OFF THE
COAST WITH THE LOW. WITH THIS IN MIND HELD ONTO SOME HIGHER POPS
FOR MON NIGHT AS THERE STILL COULD BE THE POTENTIAL FOR RAINBANDS
TO SET UP WITH MODERATE/HEAVY RAIN.
SURFACE HIGH PRESSURE WILL BUILD INTO TX LATE TUE THROUGH
THANKSGIVING HOLIDAY. TEMPS WILL BE A SOLID 10-15 DEGREES BELOW
NORMAL FOR THE HOLIDAY. ALSO NOT EXPECTING ANY HOLIDAY TRAVEL
ISSUES FOR THE HOUSTON AREA ON WEDNESDAY. HOWEVER IF YOU ARE
TRAVELING FROM HOUSTON EAST TOWARDS DCA/PHL/JFK/BOS...YOU MAY
WANT TO KEEP TRACK OF FUTURE FORECASTS. IT IS NOT LOOKING GOOD.
MARINE...
STRONG COLD FRONT HAS MOVED INTO SOUTHEAST TEXAS THIS MORNING AND
WILL BEGIN PUSHING INTO THE BAYS LATE THIS MORNING. HAVE ISSUED
ADVISORIES FOR ALL WATERS BEGINNING THIS AFTERNOON AS STRONG
OFFSHORE WINDS AND BUILDING SEAS ARE EXPECTED IN THE WAKE OF THE
FRONT. SOME GUSTS TO GALE FORCE WILL BE POSSIBLE TODAY. STRONG
OFFSHORE WINDS WILL PERSIST THROUGH THE WEEKEND AND ADVISORIES
WILL LIKELY BE EXTENDED INTO SATURDAY OR SUNDAY. A COASTAL LOW IS
FORECAST TO DEVELOP AND MOVE ACROSS THE UPPER TEXAS COASTAL WATERS
ON MONDAY...WITH STRONG OFFSHORE WINDS THEN PERSISTING IN ITS WAKE
THROUGH MID WEEK. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 47 38 46 36 44 / 70 50 60 20 60
HOUSTON (IAH) 69 43 50 42 50 / 80 50 50 20 30
GALVESTON (GLS) 68 50 55 44 53 / 70 50 50 40 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR THE
FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS
FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60
NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT
20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
&&
$$
AVIATION/MARINE...23
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
949 AM CST FRI NOV 22 2013
.DISCUSSION...
STRONG COLD FRONT WILL CONTINUE TO MOVE OFF THE COAST THIS MORNING AND
ACROSS THE COASTAL WATERS THIS AFTERNOON. BEHIND THE FRONT...SEEING
SOME 1 TO 2 INCH RAINFALL TOTALS ACROSS THE HOUSTON AREA ON THE HARRIS
COUNTY FLOOD WARNING SYSTEM WEBSITE AS A BAND OF SHOWERS AND THUNDERSTORMS
MOVES ACROSS THE AREA. TEMPERATURES BEHIND THE FRONT HAVE FALLEN INTO
THE 40S AND 50S...AND DO NOT EXPECT TO SEE ANY WARMUP FOR THE REMAINDER
OF THE DAY. CURRENT FORECAST AND DISCUSSIONS BELOW ARE RIGHT ON TRACK...AND
AT THIS TIME WILL NOT ISSUE A MORNING UPDATE. 42
&&
.PREV DISCUSSION... /ISSUED 609 AM CST FRI NOV 22 2013/
DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION
AVIATION...
A STRONG COLD FRONT IS MOVING ACROSS SOUTHEAST TEXAS THIS MORNING
AND WILL APPROACH IAH WITHIN THE NEXT HOUR. THE FRONT IS MAKING A
QUICKER PUSH THROUGH OUR WESTERN COUNTIES SO THE BOUNDARY MAY
LIKELY MAKE IT THROUGH SGR BEFORE HOU AND WILL CLEAR MATAGORDA BAY
BEFORE MOVING THROUGH GLS. EXPECT SCATTERED SHOWERS AND
THUNDERSTORMS WITH THE FRONTAL PASSAGE AND THEN LINGERING LIGHT
RAIN AND IFR CIGS PERSISTING THROUGH THE TAF PERIOD. 38
.PREV DISCUSSION... /ISSUED 451 AM CST FRI NOV 22 2013/
DISCUSSION...
THE COLD FRONT HAS PUSHED INTO SE TX THIS MORNING AND BASICALLY
LOCATED FROM BRENHAM TO HUNTSVILLE TO JUST WEST OF NACOGDOCHES.
TEMPS AT COLLEGE STATION HAVE DROPPED FROM LOW 70S TO LOW 50S IN
AN HOUR AND NOW HOVERING AROUND 50F. FRONT HAS JUST PUSHED THROUGH
HUNTSVILLE SO EXPECT A SIMILAR DROP IN TEMPS THE NEXT HOUR OR TWO.
MAIN CONCERN TODAY WILL BE THE FRONTAL PASSAGE AND TEMPS DROPPING
BEHIND IT. THE 06Z HRRR SEEMS TO BE ABOUT AN HOUR SLOW WITH THE
FRONT. WITH THAT IN MIND...THINK FRONT REACHES KCXO AROUND 12Z AND
THEN KIAH AROUND 14-15Z. FRONT MAY REACH MATAGORDA BAY AROUND
16-17Z WHICH IS ABOUT THE SAME TIME IT SHOULD PUSH THROUGH KHOU.
FRONT WILL SLOWLY PUSH OFF THE COAST AROUND 18Z. TEMPS SHOULD DROP
BEHIND THE FRONT THROUGH THE AFTERNOON. TEMPS CLOSELY FOLLOW
RECENT RAP/NAM RUNS WHICH ALSO SEEM TO HAVE A GOOD HANDLE ON THE
FRONT AND POST FRONTAL TEMPS. THIS MEANS THAT TEMPS WILL BE IN THE
40S FOR THE COLLEGE STATION AREA DURING THE AFTERNOON WITH 50S FOR
HOUSTON AREA. TEMPS WILL DROP QUICKLY INTO THE 40S OVERNIGHT.
THUNDERSTORM CHANCES HAVE BEEN KEPT HIGH AROUND 70/80 PERCENT AND
THEN HIGHER BEHIND THE FRONT FOR POST FRONTAL RAIN. WILL KEEP SOME
RAIN CHANCES GOING FRI NIGHT INTO SAT AS A WEAK VORTICITY MAX
MOVES OVER THE AREA AND FRONTOGENESIS FROM 850MB FRONT INCREASES.
DEEPER COLD AIR MOVES INTO THE AREA SAT NIGHT INTO SUN AND
BOUNDARY LAYER ALSO DRIES OUT BASED ON MODEL SOUNDINGS. HAVE LOWER
POPS FROM NE TO SW FOR SAT NIGHT AND SUN. SUNDAY EXPECT A STRONGER
VORTICITY MAX TO MOVE OVER THE AREA WHICH WILL BE IN ADVANCE OF
MAIN UPPER LEVEL LOW OVER THE DESERT SW. UPPER LOW WILL SLOWLY
MOVE ACROSS THE S ROCKIES SUN NIGHT INTO MON. IN RESPONSE...EXPECT
INCREASES ISENTROPIC LIFT EVIDENT AT 290K/295K SURFACES. SO RAIN
CHANCES WILL BE ON THE INCREASE SUN NIGHT INTO MON. INCREASED POPS
TO 70 PERCENT ON MONDAY BUT COULD VERY WELL HAVE GONE HIGHER.
DECIDED TO WAIT FOR A COUPLE MORE RUNS BUT EVERYTHING POINTS TO A
VERY WET MONDAY. COULD SEE 1-2 INCHES OF RAIN AREAWIDE FOR SE TX
FOR MONDAY. MOISTURE WILL BE STREAMING OVER THE FRONTAL SURFACE
FOR LIFT AS WELL AS INCREASED OMEGA AS THE UPPER LOW MOVES INTO
TX. LARGE SCALE ASCENT WILL NOT BE LACKING ON MONDAY AND WILL
PERSIST INTO MON NIGHT. THE HARDEST DETAILS WILL BE TO DETERMINE
EXACTLY WHERE/HOW RAIN BANDS SET UP. ALSO NOTE THAT THE BOUNDARY
LAYER WILL BE QUITE COLD UNDER THE FRONTAL SURFACE. NAM/GFS MODEL
SOUNDINGS WILL BE QUITE BORDERLINE FOR RAIN/FREEZING RAIN FROM
KCLL TO KLFK. NOT GOING TO GO WITH FROZEN PRECIP YET AS THINK SFC
WILL STAY WARM ENOUGH AND THERE IS A SOLID WARM NOSE OF 5-8C
THROUGH A 8000FT LAYER BETWEEN 925-700MB.
THERE ARE STILL SOME TIMING DIFFERENCES BETWEEN THE
NAM/GFS/ECMWF. NAM/ECMWF SOLUTIONS ARE A BIT FASTER WITH TAKING
THE COASTAL LOW FROM THE NW GULF INTO LA COAST. THEY ALSO BRING
THE SFC LOW CLOSER TO THE UPPER TX COAST WHICH WOULD ONLY ADD TO
RAINFALL POTENTIAL. GFS IS ABOUT 6 HRS SLOWER AND FARTHER OFF THE
COAST WITH THE LOW. WITH THIS IN MIND HELD ONTO SOME HIGHER POPS
FOR MON NIGHT AS THERE STILL COULD BE THE POTENTIAL FOR RAINBANDS
TO SET UP WITH MODERATE/HEAVY RAIN.
SURFACE HIGH PRESSURE WILL BUILD INTO TX LATE TUE THROUGH
THANKSGIVING HOLIDAY. TEMPS WILL BE A SOLID 10-15 DEGREES BELOW
NORMAL FOR THE HOLIDAY. ALSO NOT EXPECTING ANY HOLIDAY TRAVEL
ISSUES FOR THE HOUSTON AREA ON WEDNESDAY. HOWEVER IF YOU ARE
TRAVELING FROM HOUSTON EAST TOWARDS DCA/PHL/JFK/BOS...YOU MAY
WANT TO KEEP TRACK OF FUTURE FORECASTS. IT IS NOT LOOKING GOOD.
&&
.MARINE...
STRONG COLD FRONT HAS MOVED INTO SOUTHEAST TEXAS THIS MORNING AND
WILL BEGIN PUSHING INTO THE BAYS LATE THIS MORNING. HAVE ISSUED
ADVISORIES FOR ALL WATERS BEGINNING THIS AFTERNOON AS STRONG
OFFSHORE WINDS AND BUILDING SEAS ARE EXPECTED IN THE WAKE OF THE
FRONT. SOME GUSTS TO GALE FORCE WILL BE POSSIBLE TODAY. STRONG
OFFSHORE WINDS WILL PERSIST THROUGH THE WEEKEND AND ADVISORIES
WILL LIKELY BE EXTENDED INTO SATURDAY OR SUNDAY. A COASTAL LOW IS
FORECAST TO DEVELOP AND MOVE ACROSS THE UPPER TEXAS COASTAL WATERS
ON MONDAY...WITH STRONG OFFSHORE WINDS THEN PERSISTING IN ITS WAKE
THROUGH MID WEEK. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 47 38 46 36 44 / 70 50 60 20 60
HOUSTON (IAH) 69 43 50 42 50 / 80 50 50 20 30
GALVESTON (GLS) 68 50 55 44 53 / 70 50 50 40 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR THE
FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS
FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60
NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT
20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...42
AVIATION/MARINE...23
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
451 AM CST FRI NOV 22 2013
.DISCUSSION...
THE COLD FRONT HAS PUSHED INTO SE TX THIS MORNING AND BASICALLY
LOCATED FROM BRENHAM TO HUNTSVILLE TO JUST WEST OF NACOGDOCHES.
TEMPS AT COLLEGE STATION HAVE DROPPED FROM LOW 70S TO LOW 50S IN
AN HOUR AND NOW HOVERING AROUND 50F. FRONT HAS JUST PUSHED THROUGH
HUNTSVILLE SO EXPECT A SIMILAR DROP IN TEMPS THE NEXT HOUR OR TWO.
MAIN CONCERN TODAY WILL BE THE FRONTAL PASSAGE AND TEMPS DROPPING
BEHIND IT. THE 06Z HRRR SEEMS TO BE ABOUT AN HOUR SLOW WITH THE
FRONT. WITH THAT IN MIND...THINK FRONT REACHES KCXO AROUND 12Z AND
THEN KIAH AROUND 14-15Z. FRONT MAY REACH MATAGORDA BAY AROUND
16-17Z WHICH IS ABOUT THE SAME TIME IT SHOULD PUSH THROUGH KHOU.
FRONT WILL SLOWLY PUSH OFF THE COAST AROUND 18Z. TEMPS SHOULD DROP
BEHIND THE FRONT THROUGH THE AFTERNOON. TEMPS CLOSELY FOLLOW
RECENT RAP/NAM RUNS WHICH ALSO SEEM TO HAVE A GOOD HANDLE ON THE
FRONT AND POST FRONTAL TEMPS. THIS MEANS THAT TEMPS WILL BE IN THE
40S FOR THE COLLEGE STATION AREA DURING THE AFTERNOON WITH 50S FOR
HOUSTON AREA. TEMPS WILL DROP QUICKLY INTO THE 40S OVERNIGHT.
THUNDERSTORM CHANCES HAVE BEEN KEPT HIGH AROUND 70/80 PERCENT AND
THEN HIGHER BEHIND THE FRONT FOR POST FRONTAL RAIN. WILL KEEP SOME
RAIN CHANCES GOING FRI NIGHT INTO SAT AS A WEAK VORTICITY MAX
MOVES OVER THE AREA AND FRONTOGENESIS FROM 850MB FRONT INCREASES.
DEEPER COLD AIR MOVES INTO THE AREA SAT NIGHT INTO SUN AND
BOUNDARY LAYER ALSO DRIES OUT BASED ON MODEL SOUNDINGS. HAVE LOWER
POPS FROM NE TO SW FOR SAT NIGHT AND SUN. SUNDAY EXPECT A STRONGER
VORTICITY MAX TO MOVE OVER THE AREA WHICH WILL BE IN ADVANCE OF
MAIN UPPER LEVEL LOW OVER THE DESERT SW. UPPER LOW WILL SLOWLY
MOVE ACROSS THE S ROCKIES SUN NIGHT INTO MON. IN RESPONSE...EXPECT
INCREASES ISENTROPIC LIFT EVIDENT AT 290K/295K SURFACES. SO RAIN
CHANCES WILL BE ON THE INCREASE SUN NIGHT INTO MON. INCREASED POPS
TO 70 PERCENT ON MONDAY BUT COULD VERY WELL HAVE GONE HIGHER.
DECIDED TO WAIT FOR A COUPLE MORE RUNS BUT EVERYTHING POINTS TO A
VERY WET MONDAY. COULD SEE 1-2 INCHES OF RAIN AREAWIDE FOR SE TX
FOR MONDAY. MOISTURE WILL BE STREAMING OVER THE FRONTAL SURFACE
FOR LIFT AS WELL AS INCREASED OMEGA AS THE UPPER LOW MOVES INTO
TX. LARGE SCALE ASCENT WILL NOT BE LACKING ON MONDAY AND WILL
PERSIST INTO MON NIGHT. THE HARDEST DETAILS WILL BE TO DETERMINE
EXACTLY WHERE/HOW RAIN BANDS SET UP. ALSO NOTE THAT THE BOUNDARY
LAYER WILL BE QUITE COLD UNDER THE FRONTAL SURFACE. NAM/GFS MODEL
SOUNDINGS WILL BE QUITE BORDERLINE FOR RAIN/FREEZING RAIN FROM
KCLL TO KLFK. NOT GOING TO GO WITH FROZEN PRECIP YET AS THINK SFC
WILL STAY WARM ENOUGH AND THERE IS A SOLID WARM NOSE OF 5-8C
THROUGH A 8000FT LAYER BETWEEN 925-700MB.
THERE ARE STILL SOME TIMING DIFFERENCES BETWEEN THE
NAM/GFS/ECMWF. NAM/ECMWF SOLUTIONS ARE A BIT FASTER WITH TAKING
THE COASTAL LOW FROM THE NW GULF INTO LA COAST. THEY ALSO BRING
THE SFC LOW CLOSER TO THE UPPER TX COAST WHICH WOULD ONLY ADD TO
RAINFALL POTENTIAL. GFS IS ABOUT 6 HRS SLOWER AND FARTHER OFF THE
COAST WITH THE LOW. WITH THIS IN MIND HELD ONTO SOME HIGHER POPS
FOR MON NIGHT AS THERE STILL COULD BE THE POTENTIAL FOR RAINBANDS
TO SET UP WITH MODERATE/HEAVY RAIN.
SURFACE HIGH PRESSURE WILL BUILD INTO TX LATE TUE THROUGH
THANKSGIVING HOLIDAY. TEMPS WILL BE A SOLID 10-15 DEGREES BELOW
NORMAL FOR THE HOLIDAY. ALSO NOT EXPECTING ANY HOLIDAY TRAVEL
ISSUES FOR THE HOUSTON AREA ON WEDNESDAY. HOWEVER IF YOU ARE
TRAVELING FROM HOUSTON EAST TOWARDS DCA/PHL/JFK/BOS...YOU MAY
WANT TO KEEP TRACK OF FUTURE FORECASTS. IT IS NOT LOOKING GOOD.
&&
.MARINE...
STRONG COLD FRONT HAS MOVED INTO SOUTHEAST TEXAS THIS MORNING AND
WILL BEGIN PUSHING INTO THE BAYS LATE THIS MORNING. HAVE ISSUED
ADVISORIES FOR ALL WATERS BEGINNING THIS AFTERNOON AS STRONG
OFFSHORE WINDS AND BUILDING SEAS ARE EXPECTED IN THE WAKE OF THE
FRONT. SOME GUSTS TO GALE FORCE WILL BE POSSIBLE TODAY. STRONG
OFFSHORE WINDS WILL PERSIST THROUGH THE WEEKEND AND ADVISORIES
WILL LIKELY BE EXTENDED INTO SATURDAY OR SUNDAY. A COASTAL LOW IS
FORECAST TO DEVELOP AND MOVE ACROSS THE UPPER TEXAS COASTAL WATERS
ON MONDAY...WITH STRONG OFFSHORE WINDS THEN PERSISTING IN ITS WAKE
THROUGH MID WEEK. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 47 38 46 36 44 / 70 50 60 20 60
HOUSTON (IAH) 69 43 50 42 50 / 80 50 50 20 30
GALVESTON (GLS) 68 50 55 44 53 / 70 50 50 40 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY FROM NOON TODAY TO MIDNIGHT CST TONIGHT FOR
THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS
FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60
NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT
20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...39
AVIATION/MARINE...38
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1150 PM CST THU NOV 21 2013
.AVIATION...
HAVING TO MAKE SOME TWEAKS TO THE FCST BASED ON CURRENT TRENDS OF
THE COLD FRONT. HAVE LEANED HEAVILY ON THE HRRR FOR THESE TAFS AS
ALL THE OTHERS HAVE KEPT WITH THE MUCH SLOWER MOVEMENT. AS SUCH A
WET/COLD/BREEZY FCST DAY WILL PREVAIL FRI. 41
&&
.PREV DISCUSSION... /ISSUED 931 PM CST THU NOV 21 2013/
FRONT IS MAKING GOOD SWD PROGRESS AND EXPECT IT TO BE ALONG A
LINE FROM ROUGHLY COLUMBUS-TRINITY BY 6 AM AND ALONG THE BEACHES
BY NOON. ONGOING TEMPERATURES AND TIMING MATCH UP PRETTY WELL WITH
THE RAW NAM12 DATA AND ADJUSTED SHORT TERM GRIDS AND GAVE THAT
MODELS SOME PRETTY HEAVY WEIGHT.
SHRA/TSTMS CONTINUE DEVELOPING IN N TX AHEAD OF THE FRONT. SVR WX
THREAT FAIRLY MINIMAL BUT THERE HAVE BEEN SOME ISOLATED STRONG/SEVERE
CELLS UP THERE AND ANTICIPATE SIMILAR HERE AHEAD OF THE BOUNDARY.
SOME HEAVY DOWNPOURS MORE LIKELY WITH RESIDENT PW`S AROUND 1.7"
BEING ABOUT 2 STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF
YEAR. NEXT SHIFT MAY BE ABLE TO REDUCE MID/LATE AFTN POPS AS
INCOMING 0Z GUIDANCE ISN`T QUITE AS BULLISH WITH OVERRUNNING
PRECIP ACCUMULATIONS BUT WILL LEAVE THAT DECISION TO THEM AFTER
SEEING THE FULL MODEL SUITE. SHOULD BE A CLOUDY COLD BREEZY NASTY
AFTERNOON REGARDLESS. 47
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 56 56 38 45 36 / 70 70 50 40 20
HOUSTON (IAH) 72 74 43 51 41 / 50 70 60 50 20
GALVESTON (GLS) 71 73 50 55 45 / 40 70 60 50 30
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...99
AVIATION/MARINE...41
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1119 PM CST THU NOV 21 2013
.DISCUSSION...
SEE AVIATION FOR THE 06Z TAF DISCUSSION.
&&
.AVIATION...
AT 05Z THE COLD FRONT WAS MOVING SOUTH ACROSS BURNET AND LLANO
COUNTIES. THE LATEST RUC13 MODEL GUIDANCE HAS THE BEST HANDLE ON
THE MOVEMENT OF THE COLD FRONT. BASED ON CURRENT TRENDS AND MODEL
GUIDANCE HAVE MOVED UP THE FROPA 1 HOUR AT THE I-35 TERMINALS.
MVFR CONDITIONS WILL PREVAIL IN ADVANCE OF THE FROPA LOWERING TO
IFR A FEW HOURS AFTER FROPA. THERE WILL BE A BRIEF IMPROVEMENT
TO MVFR FRIDAY AFTERNOON BEFORE LOWERING TO IFR ONCE AGAIN FRIDAY
EVENING. SHOWERS AND THUNDERSTORMS WILL ACCOMPANY THE FROPA WITH
POST-FRONTAL ELEVATED SHOWERS TRANSITIONING TO LIGHT RAIN AND
DRIZZLE ON FRIDAY. POST-FRONTAL SFC WINDS WILL BE NORTHERLY AT 15
TO 25 KTS WITH GUSTS OF 30 KTS.
&&
.PREV DISCUSSION... /ISSUED 856 PM CST THU NOV 21 2013/
UPDATE...
ARCTIC FRONT ALONG A PECOS TO SAN ANGELO TO STEPHENVILLE LINE WAS
SURGING SOUTH AHEAD OF SCHEDULE. NOW EXPECT FRONT WILL ENTER THE
NORTHERN HILL COUNTRY AROUND MIDNIGHT...MOVE ACROSS THE AUSTIN AND
SAN ANTONIO AREAS BETWEEN 2 AND 4 AM AND EXIT SOUTH CENTRAL TEXAS
BY SUNRISE. AS A RESULT...HAVE LOWERED TEMPERATURES AND DEW POINTS
FOR OVERNIGHT INTO FRIDAY ALONG WITH AN EARLIER ONSET OF MODERATE
GUSTY NORTHERLY WINDS. ALSO...HAVE REMOVED MENTION OF THUNDER FOR
FRIDAY AS INSTABILITY IS GONE AND CHANGED SHOWERS TO LIGHT RAIN.
REMAINDER OF SOUTH CENTRAL TEXAS FORECAST IS ON TRACK. 18Z MODEL
SUITE AND NEW 00Z NAM CONTINUE TO SUGGEST A MIX OF LIGHT SLEET AND
RAIN DURING THE OVERNIGHT INTO EARLY MORNING HOURS FRIDAY NIGHT
THROUGH MONDAY MORNING.
PREV DISCUSSION... /ISSUED 535 PM CST THU NOV 21 2013/
DISCUSSION...
SEE AVIATION FOR THE 00Z TAF DISCUSSION.
AVIATION...
AT 23Z THE COLD FRONT WAS MOVING SOUTHWARD ACROSS NORTH TEXAS. THE
FRONT WILL MOVE INTO THE HILL COUNTRY AFTER MIDNIGHT...REACHING
THE TEXAS COAST BY EARLY AFTERNOON ON FRIDAY. THE TIMING OF THE
FROPA AND ASSOCIATED WIND SHIFT AT THE TERMINALS WILL BE BASED ON
A BLEND OF THE LATEST RUC AND LAMP GUIDANCE. NUMEROUS SHOWERS AND
ISOLATED THUNDERSTORMS WILL OCCUR IN THE VICINITY OF THE FRONTAL
BOUNDARY AS IT INTERACTS WITH THE MOISTURE LADEN GULF AIRMASS.
POST-FRONTAL PCPN WILL BE MAINLY ELEVATED SHOWERS.
I-35 TERMINALS...VFR CONDITIONS WILL LOWER TO MVFR BETWEEN 02Z AND
04Z...LOWERING TO IFR BY 15Z. THE BEST CHANCE FOR CONVECTION TO
IMPACT THE TAFS SITES WILL BE A FEW HOURS BEFORE AND DURING THE
FROPA. WINDS WILL SHIFT TO THE NORTH AT 12 TO 15 KTS WITH GUSTS OF
25 KTS. FROPA AT KAUS...08Z...KSAT AND KSSF AROUND 10Z.
THE KDRT TERMINAL...VFR CONDITIONS WILL LOWER TO MVFR BY 01Z...IFR
BY 08Z...IMPROVING TO MVFR BY 22Z. ORGANIZED CONVECTION IS EXPECTED
TO STAY EAST OF THE TERMINAL. WINDS WILL SHIFT TO THE NORTH AT 15
TO 20 KTS WITH GUSTS OF 25 KTS FOLLOWING THE FROPA. FROPA IS EXPECTED
AROUND 08Z.
PREV DISCUSSION... /ISSUED 318 PM CST THU NOV 21 2013/
SHORT TERM (TONIGHT THROUGH FRIDAY NIGHT)...
THE STRONG COLD FRONT HAS REACHED THE PANHANDLE. THE COLD AIR
ADVECTION IN THE WAKE OF THE FRONT IS CLEARLY EVIDENT...SFC OBS
INDICATE TEMPERATURES PLUMMETING BY 20 DEGREES OR MORE IN THE WAKE
OF THE FROPA. THE FRONT WILL CONTINUE TO PUSH SOUTHWARD ACROSS THE
STATE TONIGHT AND WILL REACH THE HILL COUNTRY BEFORE SUNRISE. THE
FRONT WILL CONTINUE TO QUICKLY MOVE THROUGH THE AREA...AND IS
EXPECTED TO REACH OUR SOUTHERN COUNTIES BEFORE NOON. DUE TO THE
TIMING OF THE FROPA...CALENDAR DAY "HIGH" TEMPERATURES FOR FRIDAY
WILL OCCUR DURING THE OVERNIGHT HOURS TONIGHT. TEMPERATURES DURING
THE DAY ON FRIDAY WILL FALL BEHIND THE FRONT...WITH AFTERNOON
TEMPERATURES REMAINING IN THE 40S (UPPER 30S HILL COUNTRY). STRONG
NORTHERLY WINDS OF 15 TO 25 MPH WILL LEAD TO WIND CHILLS IN THE
LOW TO MID 30S ACROSS MUCH OF THE AREA...AND INTO THE MID/UPPER
20S ACROSS THE HILL COUNTRY.
CHANCES FOR RAIN WILL INCREASE TONIGHT AND PERSIST THROUGH THE
WEEKEND. ISOLATED THUNDERSTORMS ARE POSSIBLE THIS EVENING THROUGH
FRIDAY. TEMPERATURES FRIDAY NIGHT WILL FALL INTO THE MID-30S ACROSS
THE HILL COUNTRY...BRINGING THE POTENTIAL FOR ISOLATED LIGHT SLEET
TO MIX-IN WITH THE COLD RAIN. NO SLEET ACCUMULATIONS ARE EXPECTED.
THE LINGERING MOISTURE/CHANCES FOR RAIN/CLOUD COVER WILL OTHERWISE
KEEP LOW TEMPERATURES IN THE UPPER 30S TO LOW 40S FRIDAY NIGHT.
LONG TERM (SATURDAY THROUGH THURSDAY)...
A DEEP UPPER LOW PARKED OVER THE SOUTHWESTERN U.S. WILL KEEP CLOUDY
SKIES AND GOOD CHANCES FOR RAIN OVER THE WEEKEND AND INTO EARLY
NEXT WEEK. HIGH TEMPERATURES WILL REMAIN UNSEASONABLY COLD. THERE
IS A RENEWED CHANCE FOR ISOLATED LIGHT SLEET TO MIX-IN WITH THE
RAIN ACROSS THE HILL COUNTRY SATURDAY NIGHT/SUNDAY MORNING AND
AGAIN SUNDAY NIGHT/MONDAY MORNING. SURFACE TEMPERATURES ARE
EXPECTED TO REMAIN ABOVE FREEZING AND THEREFORE SLEET
ACCUMULATIONS ARE AGAIN NOT EXPECTED.
THE UPPER LOW WILL EJECT EASTWARD ON MONDAY. CHANCES FOR RAIN WILL
BEGIN TO DECREASE MONDAY NIGHT AND WILL END LATE TUESDAY AS THE
UPPER LOW MOVES TO OUR EAST. SKIES WILL BEGIN TO CLEAR FROM THE
WEST LATE TUESDAY...WITH SUNSHINE FINALLY RETURNING ON WEDNESDAY.
HIGH TEMPERATURES WILL BEGIN TO WARM...BUT MOSTLY CLEAR SKIES
DURING THE OVERNIGHT HOURS WILL ALLOW LOW TEMPERATURES TO FALL
INTO THE 30S ACROSS MUCH OF THE CWA. SPOTTY FREEZING TEMPERATURES
ARE POSSIBLE THANKSGIVING MORNING.
CLIMATE...
RECORD COLD HIGH TEMPERATURES FOR NOV 23 THROUGH 24:
23RD 24TH
AUSTIN CAMP MABRY...40/1937...42/1982
AUSTIN BERGSTROM....43/1957...44/1972
SAN ANTONIO.........41/1932...44/1982
DEL RIO.............40/1957...42/1918
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 43 45 39 43 38 / 90 70 70 60 60
AUSTIN BERGSTROM INTL AIRPORT 45 46 38 45 40 / 80 70 70 60 60
NEW BRAUNFELS MUNI AIRPORT 47 51 37 44 38 / 80 70 70 60 60
BURNET MUNI AIRPORT 39 39 34 41 34 / 90 70 70 60 60
DEL RIO INTL AIRPORT 46 52 38 42 36 / 50 60 60 50 50
GEORGETOWN MUNI AIRPORT 40 40 34 42 34 / 90 70 70 60 60
HONDO MUNI AIRPORT 49 53 40 46 39 / 70 70 70 60 60
SAN MARCOS MUNI AIRPORT 46 48 38 43 38 / 80 70 70 60 60
LA GRANGE - FAYETTE REGIONAL 51 56 43 48 43 / 70 70 70 60 60
SAN ANTONIO INTL AIRPORT 48 54 40 45 39 / 70 70 70 60 60
STINSON MUNI AIRPORT 52 56 42 48 42 / 70 70 70 60 60
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...13
SYNOPTIC/GRIDS...04
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
1036 PM CST THU NOV 21 2013
.DISCUSSION...PLEASE SEE THE AVIATION DISCUSSION BELOW FOR MORE
DETAILS.
&&
.AVIATION...WIDESPREAD MVFR STRATUS WL PREVAIL GIVEN THE VERY
MOIST BOUNDARY LAYER AND ONSHORE FLOW EXPECTED TNT. IFR
CONDITIONS WL BE POSSIBLE FOR PRIMARILY THE VCT AREA. THE 18Z AND
00Z GUIDANCE HAVE CAUGHT ON TO A FASTER MOVEMENT WITH THE STRONG COLD
FRONT CURRENTLY MOVING INTO THE NORTHERN HILL COUNTRY. THIS IS IN
LINE WITH THE OBSERVED FAST SWD MOVEMENT WITH MSAS SHOWING 5-8 MB
PRESSURE RISES OVER THE PAST SVRL HOURS BEHIND THE FRONT. WL THUS
GO WITH FROPA SLIGHTLY FASTER THAN THE PRIOR TAF FCST. WL GO WITH
FROPA AROUND 12Z FOR VCT AND AROUND 15Z ELSEWHERE. SUFFICIENT
MOISTURE AND LIFTING ALONG AND BEHIND THE FRONT WL PRODUCE
SCATTERED TO NUMEROUS SHOWERS. CAPES BETWEEN 1500 AND 2000 J/KG
WITH A WEAK CAP AND MODERATE LIFT WL BE ENOUGH FOR THUNDERSTORMS
ALONG AND BEHIND THE FRONT. AFTER THE INITIAL AREA OF PCPN
ASSOCIATED WITH THE FRONT...THE PCPN WL TEND TO TAPER OFF FROM
NORTH TO SOUTH BY THE AFTN/EVE AS THE FORCING DIMINISHES.
&&
.PREV DISCUSSION... /ISSUED 923 PM CST THU NOV 21 2013/
DISCUSSION...ARCTIC COLD FRONT...JUST SOUTH OF A LINE FROM
DALLAS TO SAN ANGELO AT 03Z...CONTINUES TO SURGE SOUTH AT AROUND
25 MPH. LATEST MSAS ANALYSIS SHOWS 3 HOURLY PRESSURE RISES OF
6 TO 8 MBS OVER THE BIG COUNTRY AND CROSS TIMBERS REGIONS IN
NORTHWEST TEXAS. BELIEVE 00Z RUC/RAPID REFRESH MODEL ALONG WITH
THE LATEST SREF AND 3KM TEXAS TECH MODEL HAVE A BETTER HANDLE
ON THE PROGRESSION OF THIS STRONG SHALLOW ARCTIC AIR MASS. WENT
WITH 00Z RUC WITH BRINGING IN THE FRONT SHORTLY AFTER 12Z INTO
THE NORTHERN COUNTIES AND FRONTAL PASSAGE THROUGH THE SOUTHERN
COASTAL BEND BY 18Z FRIDAY AND THROUGH THE COASTAL WATERS BY 21Z.
STRONG COLD AIR ADVECTION BEHIND THE FRONT WILL BRING DOWN THE
TEMPERATURES INTO THE 40S ACROSS THE INLAND AREAS BY AFTERNOON
AND LOWER 50S ALONG THE COAST. LOWERED THE MINIMUM TEMPS JUST
SLIGHTLY FOR FRIDAY NIGHT. NO ADJUSTMENTS WERE MADE TO THE
CURRENT WEATHER/POPS CONFIGURATION FOR FRIDAY.
PREV DISCUSSION... /ISSUED 534 PM CST THU NOV 21 2013/
DISCUSSION...PLEASE SEE THE AVIATION DISCUSSION BELOW FOR MORE
DETAILS.
AVIATION...MVFR STRATUS WL QUICKLY DEVELOP OVER THE NEXT FEW
HOURS AS A VERY MOIST BOUNDARY LAYER ALONG WITH SUBTLE COOLING WL
PROMOTE RAPID STRATUS DEVELOPMENT. A FEW ISOLATED STREAMER SHRAS
WL BE POSSIBLE TNT...MAINLY THE VCT AREA. PATCHY IFR CONDITIONS WL
ALSO BE POSSIBLE MAINLY THE VCT AREA AFTER 04Z. THE MAIN STORY WL
BE THE SLIGHTLY FASTER TIMING OF THE STRONG COLD FRONT WHICH IS
CURRENTLY MOVING RAPIDLY THROUGH NORTH TEXAS. THE 18Z MODELS HAVE
PICKED UP ON THIS FASTER MOVEMENT AND WL THUS LEAN TWDS THIS
QUICKER FROPA TIMING. AS A RESULT...WL SHOW FROPA AROUND 13Z FOR
VCT AND AROUND 16Z ELSEWHERE. SUFFICIENT MOISTURE AND LIFTING
ALONG AND BEHIND THE FRONT WL PRODUCE SCATTERED TO NUMEROUS
SHOWERS WITH EMBEDDED THUNDERSTORMS ACROSS MOST OF SOUTH TX ON
FRIDAY. THE PCPN WL TEND TO TAPER OFF FROM NORTH TO SOUTH BY THE
AFTN.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 74 75 41 49 46 / 30 70 60 70 40
VICTORIA 65 69 40 51 44 / 40 70 60 60 40
LAREDO 73 73 41 48 43 / 20 70 60 40 40
ALICE 74 75 41 48 44 / 30 70 60 60 40
ROCKPORT 72 72 46 51 47 / 30 70 60 70 40
COTULLA 65 66 40 45 42 / 50 70 60 40 30
KINGSVILLE 74 77 41 48 45 / 20 70 60 60 40
NAVY CORPUS 73 73 46 51 48 / 20 70 60 70 40
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
MB/80...AVIATION
AREA FORECAST DISCUSSION
NWS TUCSON AZ
925 PM MST SAT NOV 23 2013
.SYNOPSIS...LOW PRESSURE OVER SOUTHEASTERN CALIFORNIA AND SOUTHWEST
ARIZONA THIS EVENING WILL MOVE NORTHEAST ACROSS ARIZONA TONIGHT INTO
SUNDAY. THIS SYSTEM WILL CONTINUE TO BRING PERIODS OF VALLEY RAIN
AND MOUNTAIN SNOW THROUGH TONIGHT. RAIN AND MOUNTAIN SNOW WILL
DECREASE FROM WEST TO EAST SUNDAY FOLLOWED BY A FEW LINGERING SNOW
SHOWERS ACROSS THE WHITE MOUNTAINS MONDAY. DRY CONDITIONS WILL THEN
PREVAIL MONDAY NIGHT THROUGH FRIDAY. A GRADUAL WARMING TREND
EXPECTED DURING THE UPCOMING WEEK.
&&
.DISCUSSION...WATER VAPOR IMAGERY SHOWS THE UPPER LOW SPINNING
ACROSS EXTREME SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA. RADAR
MOSAIC SHOWS ISOLATED SHOWERS OCCURRING OVER MAINLY CENTRAL AND
EASTERN PORTIONS OF THE FORECAST AREA AT THIS TIME. HRRR MODEL SHOWS
GENERALLY ISOLATED TO LOW END SCATTERED ACTIVITY...BUT REDEVELOPMENT
OCCURS AFTER MIDNIGHT OVER THE EASTERN ZONES THROUGH THE EARLY
MORNING HOURS. THAT SAID...THE WINTER STORM WARNING AND ADVISORIES
FOR THE REMAINDER OF THE NIGHT AND INTO EARLY SUNDAY CONTINUE TO
LOOK GOOD. DAY SHIFT MAY BE ABLE TO CANCEL THESE PRODUCTS EARLIER IF
THE SHOWERS EXIT AS EARLY AS THE HRRR IS INDICATING.
LOW TEMPERATURES EXPECTED TO DROP INTO THE MID 30S TO MID 40S ACROSS
SOME OF THE CENTRAL DESERTS AND EASTERN VALLEYS. WITH CURRENT
DEWPOINT READINGS IN THE MID 30S TO MID 40S WE COULD SEE SOME FOG...
ESPECIALLY FOR AREAS EAST OF TUCSON TOWARD VAIL AND THEN TO THE
SOUTH TOWARD SONOITA...SIMILAR TO WHAT OCCURRED YESTERDAY EVENING AT
ABOUT THIS TIME. THIS IS AN AREA THAT RECEIVED SIGNIFICANT RAINS IN
THE PAST COUPLE OF DAYS...AND WITH COOLER AIR ADVECTING IN FROM THE
EAST SOME FOG MAY DEVELOP ONCE AGAIN. WILL ADD A MENTION OF PATCHY
FOG IN THE FORECAST FOR THE REMAINDER OF TONIGHT.
AS OF 04Z (9 PM MST)...TEMPERATURES RANGED FROM THE LOWER 40S TO THE
MID 50S AND THESE READINGS ARE MOSTLY ON TRACK WITH EXPECTED
OVERNIGHT LOW TEMPERATURES...SO NO CHANGES ARE PLANNED...BUT WILL
CONTINUE TO MONITOR.
DETAILS REGARDING THE FORECAST BEYOND TONIGHT ARE BELOW IN THE
PREVIOUS DISCUSSION SECTION.
&&
.AVIATION...EAST OF KTUS-KOLS LINE...WIDESPREAD RAIN AND HIGHER
ELEVATION SNOW WILL SHIFT EAST ACROSS SE AZ THROUGH TONIGHT INTO
SUNDAY MORNING WITH WIDESPREAD MVFR CIGS/VSBYS/MT OBSCURATIONS AND
OCCASIONAL IFR CIGS/VSBYS FORECAST. WEST OF KTUS-KOLS...A FEW RAIN
AND HIGH ELEVATION SNOW SHOWERS WILL LINGER THROUGH TONIGHT. IFR
VSBYS IN FOG AND MT OBSCURATIONS PSBL WEST OF THIS LINE OVERNIGHT.
SURFACE WINDS WILL GENERALLY BE ELY/SELY 8-15 KTS WITH GUSTS TO 20
KTS. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...LOW PRESSURE WILL MOVE NORTHEAST ACROSS AZ THE
REMAINDER OF THE WEEKEND. OVER SE AZ...RAIN AND MOUNTAIN SNOW WILL
SHIFT EAST TONIGHT AND END SUNDAY NIGHT IN THE WHITE MOUNTAINS.
DRY CONDITIONS WILL PREVAIL DURING THE COMING WORK WEEK WITH COOLER
THAN AVERAGE TEMPERATURES RETURNING TO NEAR NORMAL BY THANKSGIVING.
WINDS ARE NOT EXPECTED TO BE OVERLY STRONG THROUGH THE PERIOD
ALTHOUGH EASTERLY WINDS COULD GET GUSTY TUESDAY NIGHT INTO EARLY
WEDNESDAY THROUGH MOUNTAIN GAPS AND PASSES.
&&
.CLIMATE...TODAYS RAINFALL AT THE TUCSON INTERNATIONAL AIRPORT AS OF
2 PM STOOD AT 1.22" WHICH BRINGS THE 3 DAY STORM TOTAL TO 2.11". THE
2.11" RANKS AS THE 3RD WETTEST NOVEMBER THREE DAY RAIN EVENT IN
TUCSON. THE TOP TWO ARE 2.83" IN 1895 AND 2.39" IN 1900. THE MONTH
TOTAL OF 2.23" RANKS AS THE 7TH WETTEST NOVEMBER ON RECORD. TODAYS
TOTAL OF 1.22" RANKS AS THE 8TH WETTEST NOVEMBER DAY ON RECORD.
&&
.PREVIOUS DISCUSSION...AS THE LOW MOVES THROUGH THE STATE ON
SUNDAY...IT WILL SLOWLY FILL BUT STILL PLENTY OF MOISTURE AROUND
ALONG WITH COLD POOL ALOFT TO KEEP SCATTERED SHOWERS IN THE
FORECAST. SYSTEM EAST OF THE AREA ON MONDAY WITH MUCH COLDER
OVERNIGHT LOWS TUESDAY INTO WEDNESDAY. ADDING FROST TO THE FORECAST
FOR PORTIONS OF THE EASTERN ZONES.
WARMING TREND STARTING MONDAY AND CONTINUING INTO TURKEY DAY WHERE
HIGHS WILL BE AT OR SLIGHTLY ABOVE NORMAL. MODELS HINTING AS ANOTHER
PACIFIC STORM HEADED FOR THE DESERT SW NEXT SUNDAY WHICH IS JUST
OUTSIDE OF OUR 7 DAY FORECAST. SOMETHING TO WATCH THOUGH.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 11 AM MST SUNDAY FOR AZZ510-511.
WINTER WEATHER ADVISORY UNTIL 11 AM MST SUNDAY FOR AZZ512-514.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1030 PM MST SAT NOV 23 2013
.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 311 PM MST SAT NOV 23 2013
COMPLEX PATTERN TODAY AS COLDER AIR MOVED INTO SOUTHEAST UTAH...
LOWERING THE SNOW LEVELS TO THE VALLEY FLOORS. BUT SOUTHWEST
COLORADO HAS STAYED IN THE WARM SECTOR WITH THE SNOW LEVEL AROUND
8000 FEET. TELLURIDE AWOS OBSERVED LIGHT RAIN EARLIER TODAY.
SOUTHWEST COLORADO HAS BEEN A CHALLENGE WITH RESPECT TO
PRECIPITATION TYPE DURING THE PAST DAY OR TWO. CONFIDENCE IS
INCREASING THAT SNOW LEVELS WILL LOWER TO THE VALLEY FLOORS
(EXCEPT SOUTH OF CORTEZ) AS THE MOIST CONVEYOR BELT OVER ERN
ARIZONA SHIFTS INTO NWRN NEW MEXICO AND EXTREME SWRN COLORADO.
MID LEVEL TEMPS IN THE CONVEYOR BELT ARE COLDER AND DIABATIC
COOLING PROCESSES WILL RESULT IN RAIN CHANGING OVER TO SNOW. WITH
SOUTHEAST LOW LEVEL FLOW...THE RAP AND DOWNSCALED 5KM NAM SHOW THE
QPF BULLSEYE ALONG THE MONTEZUMA/LA PLATA COUNTY LINE AND
MONTICELLO UTAH WITH AREAS EXCEEDING 1 INCH OF PCPN DURING THE
NEXT 12 HOURS. THIS EQUATES TO A SNOW ACCUMULATION OF 6-12 INCHES
OF "SIERRA CEMENT" (HEAVY WET SNOW) FOR THE THIS AREA OVERNIGHT.
FOR EAST CENTRAL UTAH AND THE UNCOMPAHGRE/GRAND VALLEY...SOUTHEAST
FLOW WILL A WARMING EFFECT THAT ERODES THE COLDER SURFACE AIR.
THIS ELIMINATES THE CHANCE OF A REPEAT PERFORMANCE OF HEAVY SNOW
FROM CANYONLANDS NATIONAL PARK TO DEBEQUE CANYON. THE OVERRUNNING
PATTERN WILL NO LONGER EXIST AND THE AREAL EXTENT OF PRECIPITATION
WILL HAVE LESSENED. FARTHER NORTH...MOSTLY DRY ALTHOUGH SOME
DISSIPATING BANDS OF LIGHT SNOW MAY GENERATE FLURRIES OVER NE
UTAH/NW COLORADO.
SUNDAY AND SUNDAY NIGHT...THE CLOSED UPPER LOW WILL BE WEAKENING
AS IT MOVES INTO NWRN NEW MEXICO. ACTIVE WEATHER WILL STILL EXIST
BENEATH THE UPPER LOW SO ACCUMULATING SNOW CONTINUES ACROSS SW
COLORADO. THE MOISTURE FIELD OVER ERN UTAH AND NORTHWEST COLORADO
WILL BE ERODING. AS THE LOW CONTINUES TO TRACK ACROSS NEW
MEXICO...LOW LEVEL FLOW BECOMES NORTHWEST WHICH FAVORS THE NWRN SAN
JUANS AND THE SRN UNCOMPAHGRE PLATEAU (DALLAS DIVIDE/RIDGWAY AND
OURAY). HOWEVER...SNOW RATES WILL BE DIMINISHING AS THE UPPER LOW
WILL BE MOVING DOWNSTREAM. BY THE TIME THE UPPER LOW DOES DEPART
THE REGION LATE SUNDAY NIGHT...STORM TOTAL QPF AND SNOWFALL WILL
BE QUITE IMPRESSIVE FOR THE SRN PORTION OF THE FORECAST AREA.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 311 PM MST SAT NOV 23 2013
THE UPPER LOW WILL HAVE TRANSLATED EAST OF THE ROCKIES TO NEAR THE
TEXAS PANHANDLE BY SUNRISE ON MONDAY...THEN BE FORCED SOUTHWARD BY
A STRONG DIP IN THE NORTHERN STREAM ACROSS THE UPPER MISSISSIPPI
VALLEY. LINGERING WRAP AROUND MOISTURE WILL BE EXITING THE FAR
SOUTHERN CWA BY LATE MORNING AS THE UPPER LOW BEGINS TO BE FORCED
SOUTHWARD. THE RETREATING MOISTURE WILL BE REPLACED BY ANOTHER
BATCH OF HIGH LEVEL MOISTURE BEING TRANSPORTED IN ON THE NORTHERLY
STREAM. NAM/GFS DIFFERING A BIT WITH THE GFS SATURATING THE UPPER
END OF THE DENDRITIC LAYER NEAR 500MB. THE NAM A BIT MORE
AGGRESSIVE WITH SATURATION DOWN TO THE TOP OF THE NORTHERN DIVIDE
MOUNTAINS THROUGH A LARGER PORTION OF THE DENDRITIC LAYER. ASCENT
IS WEAK WITH OROGRAPHICS THE MAIN DRIVER IN THE NORTH FLOW SO
WOULD EXPECT ANY ACCUMULATIONS TO BE ON THE LIGHT SIDE. FOR NOW
WILL KEEP JUST SOME SMALL POPS IN PLACE THROUGH THE AFTERNOON
UNTIL MODEL AGREEMENT ALIGNS BETTER. TEMPERATURES ARE SURE TO BE
AFFECTED BY THE SNOW COVER ESPECIALLY OVER SOUTHEAST UTAH INTO
SOUTHWEST COLORADO SO UNDERCUT GUIDANCE NUMBERS IN MANY AREAS.
THERE SHOULD BE SLOW WARM-UP GOING INTO THE MID TO LATE WEEK PERIOD
THOUGH THE STRONG NORTHERN STREAM FLOW JUST OFF TO OUR NORTHEAST
WILL CONTINUE TO REINFORCE THE COLD AIR ALOFT. VALLEY INVERSIONS
STRENGTHENED BY SNOW PACK WILL CONTINUE TO PUT A DAMPER ON WARMING
SO AGAIN TEMPERATURES FROM BLENDED MODELS WERE LOWERED. A WEAK
WAVE PASSAGE ON THURSDAY MAY BRING A BIT OF PASSING HIGH CLOUDINESS
BUT IS NOT LIKELY TO ADD MUCH TO MIXING. OUT WEST...THE EASTERN
PACIFIC TROF WILL BE SPLITTING WITH ONE BATCH CATCHING THE
WESTERLIES ACROSS THE NORTHERN CONUS BORDER. THE OTHER MAIN BATCH
WILL CLOSE OFF ANOTHER LOW ALONG THE CALIFORNIA COASTLINE. SOME OF
THIS SOUTHERN ENERGY SHEARS OUT OF THE LOW AND PROGRESSES ACROSS
THE CENTRAL ROCKIES PULLING MOISTURE WITH IT. FOR NOW IT SEEMS
THIS WILL BE MAINLY IN THE FORM OF HIGH CLOUDINESS THROUGH THE
LATE WEEK PERIOD. SO FOR NOW A MAINLY DRY FORECAST LOOKS ON TRACK
FOR HOLIDAY TRAVEL WITH TEMPERATURES GRADUALLY WARMING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1022 PM MST SAT NOV 23 2013
VERY SIMILAR SCENARIO TO LAST NIGHT...AN AREA OF ENERGY AND
MOISTURE LIFTING ACROSS WESTERN COLORADO AND EASTERN UTAH TONIGHT
WITH A SOUTHERN EDGE OF MODERATE RAIN CURRENTLY NEAR KAIB.
ANOTHER BATCH OF PRECIP IS BEING PUSHED UP AGAINST THE SAN JUANS
IN THE FORM OF SNOW. EXPECT DETERIORATING FLIGHT CONDITIONS OVER MANY
OF THE TAF SITES OVERNIGHT WITH THE BIGGEST IMPACTS OVER KDRO AND
KTEX. RAIN SHOULD CHANGE OVER TO SNOW BY MORNING AT ALL SITES. MOUNTAIN
OBSCURATION WILL BE PROMINENT OVER MANY AREAS THROUGH SUNDAY NIGHT
BEFORE SOME DRYING BEGINS TO PUSH IN FROM THE NORTH.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WARNING UNTIL 3 AM MST MONDAY FOR COZ018-019.
WINTER WEATHER ADVISORY UNTIL NOON MST SUNDAY FOR COZ021.
WINTER STORM WARNING UNTIL NOON MST SUNDAY FOR COZ022-023.
UT...WINTER STORM WARNING UNTIL 3 AM MST MONDAY FOR UTZ028.
WINTER WEATHER ADVISORY UNTIL NOON MST SUNDAY FOR UTZ029.
&&
$$
SHORT TERM...PF
LONG TERM...15
AVIATION...JAM
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1251 AM EST SUN NOV 24 2013
.SYNOPSIS...
ISSUED AT 724 PM EST SAT NOV 23 2013
A RIDGE OF HIGH PRESSURE ACCOMPANIED BY AN ARCTIC AIR MASS WILL
CONTINUE TO AFFECT THE REGION THROUGH SUNDAY. THIS COLD AIR OVER
THE WARMER LAKE MICHIGAN WATERS WILL RESULT IN CONTINUED LAKE
EFFECT SNOW SHOWERS ACROSS SOUTHWEST LOWER MICHIGAN AND NORTH
CENTRAL INDIANA THROUGH SUNDAY MORNING BEFORE DIMINISHING. SOME
MORE LIGHT SNOW IS POSSIBLE MONDAY AS AN UPPER LEVEL DISTURBANCE
TRACKS ACROSS THE GREAT LAKES.
&&
.UPDATE...
ISSUED AT 724 PM EST SAT NOV 23 2013
MULTI-BAND LAKE EFFECT WITH CELLULAR NATURE CONTINUES TO IMPACT
SOUTHWEST LOWER MICHIGAN AND NORTH CENTRAL INDIANA THIS EVENING.
FETCH CONSIDERATIONS AND EASTERN LAKE SHORE LAKE AGGREGATE
TROUGHING HAVE RESULTED IN PRIMARY AREA OF CONCERN FROM EXTREME
NORTHERN BERRIEN COUNTY EXTENDING SOUTHEASTWARD THROUGH SOUTHERN
CASS...ELKHART...AND NORTHEAST KOSCIUSKO COUNTIES. BOUNDARY LAYER
INSTABILITY AND STRENGTH OF LOW LEVEL FLOW HAS ALLOWED THESE BANDS
TO PENETRATE WELL INLAND WITH BRIEF PERIODS OF 1 TO 2 INCH PER
HOUR SNOWFALL RATES WITH MOST INTENSE BANDING. SUSTAINING THESE
TYPE OF SNOWFALL RATES HAS BEEN PROBLEMATIC HOWEVER DUE TO MORE
BROKEN...CELLULAR NATURE. OUTSIDE OF THIS MAIN BAND/STRONGEST LOW
LEVEL CONVERGENCE ZONE...GENERALLY ONLY A DUSTING TO A FEW TENTHS
OF AN INCH OF SNOW HAS BEEN REPORTED. ORGANIZATION HAS BEEN
SOMEWHAT LOOSE OVER PAST FEW HOURS POSSIBLY TIED SOMEWHAT INTO
PASSAGE OF UPPER LEVEL VORT MAX LATE AFTERNOON/EARLY EVENING. SOME
SYNOPTIC CONTRIBUTION EXPECTED OVERNIGHT HOWEVER...AS WEAK SHEARED
VORT MAX DOWNSTREAM OF APPROACHING RIDGE AXIS TRACKS INTO THE
WESTERN GREAT LAKES. THUS...WILL NEED TO WATCH FOR SOME BETTER
ORGANIZATION AS WE GET INTO THE LATE EVENING HOURS.
IT STILL APPEARS AS THOUGH MAIN LIMITING FACTOR FOG SIGNIFICANT
ACCUMULATIONS OVERNIGHT WILL CONTINUE TO BE VERY DRY NATURE TO THE
AIRMASS. NAM/RAP BUFFER SOUNDINGS SUGGEST PEAK LAKE INDUCED
INSTABILITY AROUND THE 06Z TIMEFRAME WITH FAVORABLE JUXTAPOSITION
OF STRONGEST LOW LEVEL VERTICAL MOTION WITH DGZ THROUGH THE
OVERNIGHT. HOWEVER...GRADUAL LOWERING OF INVERSION TOWARD MORNING
MAY TAKE STRONGEST VERTICAL MOTIONS JUST BELOW CORE OF DGZ BY 12Z.
GIVEN ABOVE FACTORS AND LIMITING FACTOR OF DRY LARGE SCALE AIR
MASS...STILL FEEL THAT PREVIOUS FORECAST IS IN GOOD SHAPE WITH
ADVISORY LEVEL ACCUMULATIONS. CONFIDENCE IN REACHING WARNING TYPE
ACCUMS GIVEN CELLULAR NATURE AND GRADUAL LOWERING INVERSION
HEIGHTS OVERNIGHT STILL QUITE LOW AND WILL NOT MAKE ANY CHANGES TO
GOING HEADLINES.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 400 PM EST SAT NOV 23 2013
ARCTIC AIRMASS ASSOCIATED WITH 1050MB SURFACE HIGH IS CURRENTLY
ENGULFING THE REGION...LEADING TO FALLING TEMPS AND A DECENT LAKE
RESPONSE. 850MB TEMPS CONTINUE TO FALL INTO THE UPPER TEENS BELOW
ZERO AND 700MB DELTA-T`S ARE AT OR ABOVE 30C. CERTAINLY PLENTY OF
LAKE INDUCED INSTABILITY BUT DEGREE OF UPSTREAM DRY AIR AND LOW
LEVEL FLOW TRAJECTORIES REMAIN A LIMITING FACTOR. AS PREVIOUSLY
MENTIONED...SURFACE DEWPOINTS OVER WISCONSIN ARE HOVERING AT OR
BELOW ZERO. 330 DEGREE SURFACE WINDS GIVE A DECENT FETCH ALONG LAKE
MICHIGAN BUT MOISTURE AND SENSIBLE/LATENT HEAT FLUX CAN ONLY DO SO
MUCH...ESPECIALLY GIVEN STRONG GRADIENT AND MARGINAL UPSTREAM
PRECONDITIONING FROM WESTERN LAKE SUPERIOR. THIS IS BORNE OUT BY
RELATIVELY DRY NEAR SURFACE PROFILES ON FORECAST SOUNDINGS AND
CEILINGS GENERALLY ABOVE 3 KFT DURING THE DAY TODAY. DRY AIR ALOFT
IS ALSO PREVENTING CONVECTIVE DEPTHS FROM GETTING MUCH ABOVE 7
KFT...PER NAM AND RAP FORECAST SOUNDINGS. APPEARS TO BE SOME
SEMBLANCE OF FRICTIONAL CONVERGENCE OR THERMALLY-INDUCED PRESSURE
TROUGHING ALONG THE EASTERN SHORE OF LAKE MICHIGAN BUT STRONG
NORTHWEST GRADIENT IS DISRUPTING THE FORMATION OF A SINGLE DOMINANT
BAND AND HEAVIER SNOW SHOWERS HAVE BEEN FAIRLY SPORADIC AND
DISORGANIZED THROUGHOUT THE DAY. 12Z HI-RES GUIDANCE SUGGESTS BANDS
MAY BECOME A LITTLE BETTER ORGANIZED OVERNIGHT BUT THE
AFOREMENTIONED LIMITING FACTORS WILL REMAIN LARGELY IN PLACE THROUGH
THE MORNING WITH A STIFF NORTHWEST WIND...PERSISTENT SYNOPTIC-SCALE
DRY AIR ADVECTION...AND A WELL MIXED BOUNDARY LAYER. STRONG
INSTABILITY...LONG DURATION...AND NEARLY IDEAL DGZ PLACEMENT WILL
CONTINUE TO AT LEAST PARTIALLY OFFSET THOSE NEGATIVE FACTORS THOUGH
AND WILL CONTINUE TO SEE SPURTS OF HEAVIER SNOW SHOWERS THROUGH
TOMORROW MORNING THAT COULD EVENTUALLY ADD UP TO 3-5 INCHES IN THE
ADVISORY AREA. STILL DONT EXPECT WARNING CRITERIA SNOWFALL. THE ONLY
POSSIBLE EXCEPTION MAY BE IN CASS COUNTY MI WHERE 5-8 INCHES MAY BE
POSSIBLE IF A MORE ORGANIZED/FOCUSED BAND DEVELOPS BUT CONFIDENCE IN
THIS OCCURRING IS TOO LOW TO WARRANT AN UPGRADE AT THIS POINT.
BACKING LOW LEVEL WINDS AND PERSISTENT SUBSIDENCE/DRY AIR ADVECTION
WILL BRING AN END TO LAKE AFFECT SNOW SHOWERS AROUND MIDDAY TOMORROW.
OTHER MAIN STORY DURING THIS SHORT TERM PERIOD WILL BE THE VERY COLD
TEMPERATURES. STRONG GRADIENT AND LAKE INDUCED CLOUD COVER WILL
PREVENT ANY DECOUPLING OR RADIATIVE COOLING OVERNIGHT FOR MOST OF
OUR CWA BUT VERY COLD THERMAL PROFILES ADVECTING INTO THE AREA WILL
STILL SUPPORT LOWS GENERALLY IN THE MID TEENS. COMBINED WITH THE
WIND...IT WILL FEEL LIKE THE LOW SINGLE DIGITS IN SOME AREAS. HIGHS
TOMORROW WILL STRUGGLE TO GET OUT OF THE MID 20S GIVEN 925MB TEMPS
STILL AROUND -11C. MODELS CONTINUE TO STRUGGLE WITH THE MAGNITUDE OF
THIS COLD AIRMASS AND HAVE CONTINUED TO LEAN ON THE COOLER SIDE OF
GUIDANCE.
&&
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 400 PM EST SAT NOV 23 2013
PREFERENCE THIS AFTN LIES W/SHARPER H5 EVOLUTION ALOFT MID PD IN
RESPONSE TO EWD EJECTION OF STG SRN STREAM SW UNDERNEATH AMPLIFYING
NRN STREAM ACRS THE WRN LAKES WHICH PROVIDES A PATHWAY FOR SOME XPCD
PHASING ALOFT. AS SUCH AND IN TANDEM W/GEM/NAM/EC TRENDS...BUMPED
POPS CONSIDERABLY WED-THU FOR WHAT SHLD BE A SIG LK EFFECT SNOW
EVENT AS YET ANOTHER SURGE OF COLD CANADIAN AIR FUNNELS SWD ACRS THE
LAKES.
STEEP NW FLW ALOFT CONTS THROUGH THE END OF THE PD W/PROMISE OF
CONTD WELL BLO NORMAL TEMPS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1243 AM EST SUN NOV 24 2013
PRIMARY LES BAND SHOULD REMAIN JUST N-E OF KSBN AIRFIELD FOR
REMNDR OF AM HOURS. LESSER ORGANIZED BAND TO WEST WITH LWR 30 DBZ
RETURNS TO SLIDE INTO KSBN OFF/ON NEXT FEW HOURS. THEREAFTER
DERISION OF DRY AIRMASS FM BENEATH AND LOWERING SUBSIDENCE
INVERSION LEADING TO THINNING MSTR LAYER WITH POTNL FOR FUEL ALT
CONDS BECOMING TOO LOW FOR MENTION BYND 09 UTC. WEAKENING RETURNS
ON SOUTHERN PERIPHERY OF PRIMARY BAND SHOULD LEAD TO OCNL MINOR
VSBY REDUCTIONS AT KFWA AS WELL...THOUGH INLAND SUSTENANCE SUCH
THAT VFR MET CONDS EXPECTED TO DOMINATE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST THIS MORNING FOR
INZ004>006.
MI...LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST THIS MORNING FOR
MIZ077>079.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LMZ043-046.
&&
$$
UPDATE...MARSILI
SYNOPSIS...MARSILI
SHORT TERM...AGD
LONG TERM...T
AVIATION...MURPHY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS GOODLAND KS
222 AM MST SUN NOV 24 2013
.SHORT TERM...(TODAY AND TUESDAY NIGHT)
ISSUED AT 149 AM MST SUN NOV 24 2013
THE UPPER LEVEL LOW PRESSURE SYSTEM EXPECTED TO AFFECT THE
FORECAST AREA WILL MOVE SLOWLY ACROSS THE DESERT SOUTHWEST AND
SOUTHERN ROCKIES TODAY. AHEAD OF THIS SYSTEM...LIGHT SNOW WILL
SPREAD NORTHWARD OUT OF EASTERN NEW MEXICO AND THE PANHANDLE
REGION OF TEXAS AND OKLAHOMA INTO PORTIONS OF EASTERN COLORADO AND
WESTERN KANSAS. THE BEST CHANCE OF ACCUMULATING SNOWFALL WILL BE
THIS MORNING MAINLY ALONG AND SOUTH OF INTERSTATE 70 WHERE AN INCH
OR LESS OF TOTAL ACCUMULATION IS POSSIBLE.
THE UPPER LOW CENTER WILL PHASE INTO THE MAIN UPPER TROUGH THAT
DEEPENS OVER THE GREAT LAKES AND MISSISSIPPI VALLEY REGION
TONIGHT. THE LOW WILL THEN BEGIN TO MOVE SOUTHEASTWARD OVER TEXAS
WITH DRYER AIR ALOFT AND SUBSIDENCE MOVING OVER THE CENTRAL HIGH
PLAINS REGION TONIGHT. THE UPPER RIDGE AMPLIFYING OVER THE WESTERN
UNITED STATES MOVES OVER THE INTERMOUNTAIN REGION MONDAY NIGHT AND
TUESDAY AND BEGINS TO MOVE OVER THE ROCKIES ON TUESDAY NIGHT.
ALTHOUGH TEMPERATURES WILL BE GRADUALLY INCREASING THROUGH THE
FIRST PART OF THE WORK WEEK AS HIGH PRESSURE MOVES INTO THE
REGION...MODEL TRENDS HAVE BEEN CONSISTENTLY LOWERING TEMPERATURES
WITH EACH SUBSEQUENT MODEL RUN OVER THE PAST FEW DAYS. TEMPERATURES
WILL REMAIN COLDER THAN AVERAGE WITH DRY CONDITIONS EXPECTED.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 149 AM MST SUN NOV 24 2013
THE LARGE SCALE PATTERN SHOWS A LONGWAVE TROUGH OVER THE EASTERN
PORTION OF THE U.S. WITH AN UPPER RIDGE OVER THE ROCKIES.
THROUGHOUT THE EXTENDED...SEVERAL SHORTWAVE TROUGHS IN THE
NORTHWEST/WESTERLY FLOW ALOFT MOVE THROUGH THE NORTHERN
PLAINS...SENDING A FEW WEAK COLD FRONTS THROUGH THE CWA. THE COLD
AIR BEHIND THE FIRST FRONT IS KEPT WELL TO THE NORTH...SO
TEMPERATURES ARE NOT EXPECTED TO FLUCTUATE MUCH BEHIND THE FRONTAL
PASSAGE. THE FIRST FRONT MOVES THROUGH WEDNESDAY NIGHT INTO
THURSDAY AND THE NEXT FRONT...ASSOCIATED WITH WESTERLY/SOUTHWEST
FLOW ALOFT...MOVES THROUGH FRIDAY NIGHT INTO SATURDAY.
TEMPERATURES WITH THE NEXT FRONTAL PASSAGE ALSO ARE NOT EXPECTED
TO FLUCTUATE MUCH SINCE HIGHS SHOULD RECOVER AS THE SURFACE HIGH
QUICKLY PUSHES EAST BY SATURDAY AFTERNOON. FRONTAL PASSAGES WILL
ALSO REMAIN DRY AS THE MAIN FORCING WITH THESE WAVES ALSO REMAINS
NORTH OF THE CWA. TOWARDS THE END OF THE PERIOD...THE LARGE SCALE
PATTERN SHIFTS EAST WITH THE RIDGE FLATTENING AND MOVING OVER THE
CWA THURSDAY THROUGH SATURDAY...WHILE A CLOSED UPPER LOW REMAINS
OVER SOUTHERN CALIFORNIA AND SLOWLY MOVES EAST/SOUTHEAST WITH THE
SOUTHERN STREAM JET MOVING OVER THE CWA ON SATURDAY.
AS PREVIOUSLY MENTIONED...THE EXTENDED PERIOD SHOULD REMAIN
DRY...WITH INCREASING MID TO HIGH CLOUDS WITH FRONTAL PASSAGES.
TEMPERATURES SHOULD REMAIN SEASONABLE...WITH HIGHS IN THE MID 40S TO
LOW 50S AND LOWS IN THE 20S. ONCE EXCEPTION FOR HIGH TEMPERATURES
WILL BE WEDNESDAY...AS SURFACE HIGH PRESSURE OVER EASTERN KANSAS
EXTENDS INTO THE EASTERN PORTION OF THE CWA...FROM RED WILLOW TO
GOVE COUNTY AND EASTWARD...HIGHS COULD ONLY REACH THE UPPER 30S TO
LOW 40S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1041 PM MST SAT NOV 23 2013
MODELS DIVERGING ON HOW FAST AND HOW FAR NORTH TO BRING PRECIPITATION
AND RICHER LOWER LEVEL MOISTURE. AT THIS TIME IT WOULD SEEM THAT
THE NAM AND RUC ARE OVERDOING IT PER LATEST OBSERVATIONS. BOTH MODELS
ESPECIALLY THE NAM HAVE BEEN OVERDOING IT HERE RECENTLY. AT THIS
TIME IT LOOKS LIKE PRECIPITATION AND LOWER CEILINGS WILL NOT MOVE
IN UNTIL NEAR 12Z AT KGLD. WILL HAVE MVFR CEILINGS THERE UNTIL 18Z
WITH VERY LIGHT SNOW...ABOVE MVFR...AS WELL. EXPECT VFR CONDITIONS
AT KMCK THROUGH THE ENTIRE PERIOD. SOUTH WINDS WILL INCREASE FIRST
AT KGLD BETWEEN 06Z AND 12Z AND THEN KMCK BY LATE MORNING. THE
STRONGEST GUSTS WILL BE AT KGLD. GUSTS WILL STOP BY 00Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...LOCKHART
LONG TERM...ALW
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
157 AM CST Sun Nov 24 2013
...Updated long term section...
.SYNOPSIS...
ISSUED AT 1109 AM CST SAT NOV 23 2013
At 12z Saturday a -25c 500mb low was located over southern
California. A 300mb +100kt jet streak extended from the based of
this upper low northeast into the four corners region. A 700mb to
500mb deformation zone was located from Wyoming, across Colorado,
into Oklahoma and a 700mb baroclinic zone extended from southern
Colorado into northern Oklahoma. Along and south of this
baroclinic zone was also where the better 850mb to 500mb moisture
appears to be located based on upper air analysis. A surface to
850mb ridge axis extended from northeast New Mexico into southern
Nebraska. An area of high pressure at the surface at 12z was
located over the eastern Dakotas. The Dodge City sounding this
morning indicated a of drier air was located in the 900mb to 750mb
layer, however the Amarillo sounding indicated a deep layer of
moisture extending from the surface to the 700mb layer.
&&
.SHORT TERM...(This evening through Sunday)
ISSUED AT 218 PM CST SAT NOV 23 2013
Models this morning were all in decent agreement with the
southern California upper low slowly moving east across the
southwest United States over the next 24 hours. Ahead of this
upper trough, isentropic lift and moisture on the I290 and I295
surfaces will improve across southwest Kansas. As this moisture
and lift improves the clouds will thicken and lower with even some
light snow becoming possible across far southwest Kansas after 03z
based on the NAM. The latest HRRR was even a bit more aggressive
with the precipitation spreading into southwest Kansas after 00z
Sunday, and currently given the precipitation that was already
occurring near Amarillo as of 19z will begin to trend toward this
slightly quicker solution. This area of light snow will then
spread north and east through the overnight period but the better
moisture return and isentropic lift still appears to be confined
near and south of the Oklahoma border overnight. As a result not
expected much in the way of accumulation until the 300mb jet,
which was located over Arizona at 12z, begins to approach
southwest Kansas after 06z. Possible exception to this will be
extreme southwest Kansas near Elkhart.
Steady light snow will spread across southwest Kansas after 06z
Sunday as synoptic scale lift improves. Given that the moisture
and low level isentropic lift will already be in place am
currently leaning towards the NAM in snowfall amounts from roughly
06z to 18z Sunday. As a result snow amounts ranging from one to
around two inches still appear reasonable south of a Ulysses to
Dodge City to Pratt line. The higher 2 inch amounts will be mainly
confined near the Oklahoma border on Sunday. Given snow amounts of
around 2 inches being possible near the Oklahoma border was
considering a winter weather advisory, however at this time given
that this is expected to be only a marginal event over a small
area have decided to hold off with any type of headlines. Snow
accumulations of less than one inch is likely further north given
the late timing of the isentropic lift and depth of dry air
forecast in the lower levels.
.LONG TERM...(Monday through Saturday)
ISSUED AT 156 AM CST SUN NOV 24 2013
Upper level ridging will build across the Rockies early this
week...but will weaken as it moves across the western plains with
predominantly westerly mid level flow across the central and
southern plains for much of the remainder of the week. This should
keep much of the cold Canadian air to the northeast with
temperatures moderating back to seasonal averages across
southwestern Kansas. There will be one more arctic high push south
Tuesday and Wednesday. Wednesday highs are most uncertain given the
strength of this next arctic push...and the latest ECMWF suggests
temperatures remaining in the lower 30s much of the day. Wednesday
highs may need to be further lowered should this trend continue in
the models. Even if Wednesday is colder than currently forecast, it
will likely warm right back up Thursday as downslope moment really
takes over allowing temperatures to warm well into the 40s, if not a
bit warmer. The general zonal nature to the hemispheric pattern
does not favor mid-latitude cyclone development through the end of
the week, thus precipitation will not be in the forecast.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 1211 AM CST SUN NOV 24 2013
CIGS will lower to MVFR/IFR today as warm advection brings plenty
of low level moisture northward from the panhandles. Some snow is
possible after 12z, especially at KGCK and eventually at KDDC
after 15Z. Winds will increase from the south today to 10-14 kts
as a surface trough develops in the lee of the Rockies.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 29 23 38 22 / 60 10 10 10
GCK 30 21 39 22 / 70 10 10 10
EHA 29 23 35 21 / 90 10 10 10
LBL 30 22 34 22 / 90 10 10 10
HYS 31 20 40 22 / 30 10 10 0
P28 28 24 38 23 / 50 20 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY until 4 PM CST /3 PM MST/ this afternoon
FOR KSZ061>063-074>078-084>088.
&&
$$
SHORT TERM...Burgert
LONG TERM...Umscheid
AVIATION...Finch
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1219 AM CST Sun Nov 24 2013
...Updated for aviation discussion...
.SYNOPSIS...
ISSUED AT 1109 AM CST SAT NOV 23 2013
At 12z Saturday a -25c 500mb low was located over southern
California. A 300mb +100kt jet streak extended from the based of
this upper low northeast into the four corners region. A 700mb to
500mb deformation zone was located from Wyoming, across Colorado,
into Oklahoma and a 700mb baroclinic zone extended from southern
Colorado into northern Oklahoma. Along and south of this
baroclinic zone was also where the better 850mb to 500mb moisture
appears to be located based on upper air analysis. A surface to
850mb ridge axis extended from northeast New Mexico into southern
Nebraska. An area of high pressure at the surface at 12z was
located over the eastern Dakotas. The Dodge City sounding this
morning indicated a of drier air was located in the 900mb to 750mb
layer, however the Amarillo sounding indicated a deep layer of
moisture extending from the surface to the 700mb layer.
&&
.SHORT TERM...(This evening through Sunday)
ISSUED AT 218 PM CST SAT NOV 23 2013
Models this morning were all in decent agreement with the
southern California upper low slowly moving east across the
southwest United States over the next 24 hours. Ahead of this
upper trough, isentropic lift and moisture on the I290 and I295
surfaces will improve across southwest Kansas. As this moisture
and lift improves the clouds will thicken and lower with even some
light snow becoming possible across far southwest Kansas after 03z
based on the NAM. The latest HRRR was even a bit more aggressive
with the precipitation spreading into southwest Kansas after 00z
Sunday, and currently given the precipitation that was already
occurring near Amarillo as of 19z will begin to trend toward this
slightly quicker solution. This area of light snow will then
spread north and east through the overnight period but the better
moisture return and isentropic lift still appears to be confined
near and south of the Oklahoma border overnight. As a result not
expected much in the way of accumulation until the 300mb jet,
which was located over Arizona at 12z, begins to approach
southwest Kansas after 06z. Possible exception to this will be
extreme southwest Kansas near Elkhart.
Steady light snow will spread across southwest Kansas after 06z
Sunday as synoptic scale lift improves. Given that the moisture
and low level isentropic lift will already be in place am
currently leaning towards the NAM in snowfall amounts from roughly
06z to 18z Sunday. As a result snow amounts ranging from one to
around two inches still appear reasonable south of a Ulysses to
Dodge City to Pratt line. The higher 2 inch amounts will be mainly
confined near the Oklahoma border on Sunday. Given snow amounts of
around 2 inches being possible near the Oklahoma border was
considering a winter weather advisory, however at this time given
that this is expected to be only a marginal event over a small
area have decided to hold off with any type of headlines. Snow
accumulations of less than one inch is likely further north given
the late timing of the isentropic lift and depth of dry air
forecast in the lower levels.
.LONG TERM...(Sunday night through Saturday)
ISSUED AT 150 PM CST SAT NOV 23 2013
Moderation of temperatures is expected in the extended period.
Values will start below normal Monday and end up around normal by
next Saturday. No precipitation is expected during the period as
moisture will remain well southeast of the area. A series of weak
front will move across the region next week with the main impact in
the form of wind shifts.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 1211 AM CST SUN NOV 24 2013
CIGS will lower to MVFR/IFR today as warm advection brings plenty
of low level moisture northward from the panhandles. Some snow is
possible after 12z, especially at KGCK and eventually at KDDC
after 15Z. Winds will increase from the south today to 10-14 kts
as a surface trough develops in the lee of the Rockies.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 29 23 37 23 / 30 10 10 10
GCK 30 21 38 23 / 30 10 10 10
EHA 29 23 35 22 / 60 10 10 10
LBL 30 22 34 23 / 70 10 10 10
HYS 31 20 39 23 / 20 10 10 0
P28 28 24 36 24 / 50 20 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Burgert
LONG TERM...Sugden
AVIATION...Finch
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1046 PM MST SAT NOV 23 2013
.UPDATE...
ISSUED AT 837 PM MST SAT NOV 23 2013
JUST COMPLETED AN UPDATE. CLOUDS HAVE INCREASED THROUGH THE
EVENING WITH THE SOUTHERLY WINDS BEGINNING THEIR INCREASE. MANY
LOCATIONS IN THE WESTERN AND CENTRAL PORTION OF THE FORECAST AREA
MAY HAVE ALREADY REACHED THEIR MINS WITH MUCH HIGHER WINDS
EXPECTED IN THE LATER HALF OF THE NIGHT. NAM HAS CAUGHT ON THIS
AND USED THIS COMBINED WITH REALITY TO ADJUST THE MINS AND DIURNAL
TREND.
IN REGARDS TO THE WINDS INCREASED THEM EARLIER...BEGINNING BETWEEN
06Z AND 12Z. AREA SOUNDINGS CONFIRMING WHAT MODEL DATA IS SHOWING
IN REGARDS TO PRECIPITATION CHANCES. STILL A LOT OF DRY AIR IN THE
LOW LEVELS AND WILL TAKE A WHILE TO SATURATE. THAT LOOKS TO HAPPEN
BETWEEN 06Z AND 12Z WITH HIGHER POPS LATER TONIGHT INTO TOMORROW.
SO REMOVED PRECIPITATION CHANCES AND STARTED THE INCREASE AFTER
06Z A LITTLE SLOWER THAN PREVIOUSLY DEPICTED. ALSO RAMPED UP THE
SKY COVER AS WELL PER SATELLITE AND LATEST GUIDANCE.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 105 PM MST SAT NOV 23 2013
19Z WATER VAPOR IMAGERY/RUC ANALYSIS INDICATED LARGE CLOSED LOW
CIRCULATION OVER THE EXTREME SOUTHWESTERN CONUS WITH SHORTWAVE
RIDGING IN PLACE ACROSS THE CWA. AT THE SFC...1047MB SFC RIDGE
AXIS WAS NOSING INTO EASTERN KANSAS WITH CWA ON WESTERN PERIPHERY
OF THIS FEATURE.
MAIN CONCERN FOR THE SHORT TERM PERIOD WILL BE PRECIPITATION
CHANCES OVERNIGHT TONIGHT INTO TOMORROW. WHILE STORM SYSTEM IN THE
SOUTH WILL GENERALLY REMAIN WELL TO THE SOUTH OF THE CWA...PERIOD
OF ASCENT/MOISTURE ADVECTION EXPECTED TO DEVELOP TONIGHT WHICH MAY
BRING A PERIOD OF LIGHT SNOW TO AREA BTWN 09 AND 18Z. LOOKING AT
VARIOUS MODEL ISENTROPIC/STABILITY FIELDS...APPEARS THAT OVERALL
FORCING PRETTY WEAK WITH MAIN DIFFERENCE BETWEEN DRY/WET MODELS
ARE THE DEGREE OF POTENTIAL INSTABILITY PRESENT. NOT REAL
CONFIDENT IN MORE UNSTABLE SOLUTIONS SO FOR THE TIME BEING PLAN ON
TEMPERING POPS IN THE 20-40 PERCENT RANGE AND SNOW AMOUNTS. COULD
POSSIBLY SEE A FEW SPOTS OF 2-3 INCHES IN THE SOUTHWEST...BUT
THINK MOST LIKELY SCENARIO WILL BE AROUND AN INCH SOUTH OF
INTERSTATE. OTHERWISE...WINDS WILL SHIFT TO THE SOUTH AND INCREASE
LATE TONIGHT THROUGH SUNDAY INCREASING TO 20 TO 30 MPH DURING THE DAY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 227 PM MST SAT NOV 23 2013
THE LARGE UPPER LOW OVER THE SOUTHWEST U.S. WILL LIFT NORTHEAST TO
THE CO-NM BORDER SUNDAY NIGHT BEFORE HEADING BACK SOUTHEAST ACROSS
THE GULF BY TUESDAY. WEAK ASCENT AHEAD OF THE UPPER LOW AND ITS
CLOSE PROXIMITY WILL RESULT IN A BRIEF PERIOD OF LIGHT
SNOW/FLURRIES AS SHOWN ON THE SREF. ANY SNOW AMOUNTS WILL BE
LIGHT AND CONFINED TO THE SOUTHERN HALF OF THE AREA.
THE REST OF THE EXTENDED PERIOD WILL BE UNDER THE INFLUENCE OF AN
UPPER RIDGE TUESDAY-WEDNESDAY WHICH WILL ULTIMATELY FLATTEN OUT
DURING THE WEEK. NO PRECIPITATION IS EXPECTED FOR THE REMAINDER OF
THE WEEK AS A RESULT.
AT THE SURFACE...A WEAK COLD FRONT WILL PUSH THROUGH MONDAY
FOLLOWED BY A REINFORCING CANADIAN AIR MASS WHICH DOMINATES
TUESDAY-WEDNESDAY. THIS WILL KEEP TEMPERATURES BELOW NORMAL THROUGH
AT LEAST MID-WEEK WITH HIGHS IN THE 30S MONDAY WARMING TO THE 40S
BY WEDNESDAY. THE LAST HALF OF THE WEEK WILL SEE A RETURN TO
NORMAL TEMPERATURES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1041 PM MST SAT NOV 23 2013
MODELS DIVERGING ON HOW FAST AND HOW FAR NORTH TO BRING PRECIPITATION
AND RICHER LOWER LEVEL MOISTURE. AT THIS TIME IT WOULD SEEM THAT
THE NAM AND RUC ARE OVERDOING IT PER LATEST OBSERVATIONS. BOTH MODELS
ESPECIALLY THE NAM HAVE BEEN OVERDOING IT HERE RECENTLY. AT THIS
TIME IT LOOKS LIKE PRECIPITATION AND LOWER CEILINGS WILL NOT MOVE
IN UNTIL NEAR 12Z AT KGLD. WILL HAVE MVFR CEILINGS THERE UNTIL 18Z
WITH VERY LIGHT SNOW...ABOVE MVFR...AS WELL. EXPECT VFR CONDITIONS
AT KMCK THROUGH THE ENTIRE PERIOD. SOUTH WINDS WILL INCREASE FIRST
AT KGLD BETWEEN 06Z AND 12Z AND THEN KMCK BY LATE MORNING. THE
STRONGEST GUSTS WILL BE AT KGLD. GUSTS WILL STOP BY 00Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...JRM
LONG TERM...DLF
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GRAY ME
1234 AM EST SUN NOV 24 2013
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION TONIGHT WITH A STRONG NORTHWEST
FLOW SETTING UP BEHIND IT. HIGH PRESSURE WILL BUILD SOUTH OF NEW
ENGLAND SUNDAY THROUGH MONDAY. A COLD FRONT WILL SLOWLY APPROACH
FROM THE WEST MONDAY NIGHT AND TUESDAY AND WILL CROSS THE REGION
TUESDAY NIGHT. LOW PRESSURE WILL MOVE UP THE EAST COAST ON
WEDNESDAY. HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE WEST
THURSDAY THROUGH FRIDAY. HIGH PRESSURE WILL CREST OVER THE REGION
ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
1225 AM...A MINOR ESTF TO ADJUST 1ST PERIOD GRIDS TO REFLECT
MESONET. WINDS HAVE COME UP QUICKER ON THE WATERS AND THE GALE
WILL BE STARTED AS OF 05Z.
PREV DISC...
UPDATE...HAVE UPDATED POP ONCE AGAIN TO TRACK THE LATEST
BATCH OF SN SQUALLS CROSSING THE WHITE MTNS ATTM. THE 24/00Z HRRR
ACTUALLY HAS A VERY GOOD HANDLE ON THE CURRENT SPEED AND FAIR
ESTIMATE ON LOCATION OF THE SQUALL. SO HAVE BLENDED THE PREVIOUS
FORECAST WITH THIS LATEST GUIDANCE TO BRING THE OFFICIAL FORECAST
IN THAT DIRECTION FOR THE NEXT SEVERAL HOURS. WILL CONTINUE HEAVY
SNFL WORDING WITH THIS PCPN...AS EVEN THOUGH THE DURATION WILL BE
SHORT LIVED...THE INTENSITY WILL BE ENOUGH TO CAUSE TROUBLE.
PREVIOUS DISCUSSION...ARCTIC COLD FNT MAKING QUICK PROGRESS
TOWARDS THE CWFA ATTM. SHSN AND SQUALLS WILL BECOME MORE NUMEROUS
AS IT APPROACHES THIS EVENING. STRONG CAA IS DESTABILIZING THE
LLVLS...ALLOWING SHSN TO BECOME QUITE INTENSE AT TIMES. LOOKING AT
UPSTREAM OBS AND WEBCAMS...VSBYS WILL DROP TO 1/4SM OR LESS AT
TIMES. HAVE ADDED HEAVY SN WORDING TO SRN NH AND ADJACENT SWRN ME
FOR THE NEXT SEVERAL HOURS AS SQUALLS TRACK OVER THESE AREAS.
ADDITIONALLY...ABOVE FREEZING TEMPS TODAY WILL MEAN ROAD TEMPS
WILL BE WARM ENOUGH TO MELT SNFL INITIALLY. HOWEVER...RAPIDLY
FALLING TEMPS WILL MEAN THIS WILL REFREEZE...CREATING VERY ICY
ROADWAYS. SEEING AS THESE SHSN WILL BE CROSSING INTERSTATES
89...93...AND 95 THIS IS A CONCERN. USED A BLEND OF THE LATEST RAP
AND HRRR TO TREND POP OVER THE NEXT FEW HOURS. OTHERWISE FORECAST
LOOKS ON TRACK AS BITTER COLD HEADS TOWARDS THE REGION.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 AM MONDAY/...
FOR SUNDAY WE HAVE ISSUED A WIND ADVISORY. LOOKING AT BUFKIT DATA
SHOWS WINDS TO 40 TO 50 KTS DOWN TO 2K FEET WITH STEEP LAPSE
RATES. THE STRONGEST WINDS ARE LIKELY TO BE IN THE 18Z TO 03Z TIME
FRAME. WINDS GUSTS TO 45 TO 50 MPH ARE CERTAINLY POSSIBLE. EXPECT
THERE WILL BE POWER OUTAGES AS THE DAY GOES ON. TEMPERATURES WILL
RISE ABOUT 5 TO 10 DEGREES TOMORROW WHICH WILL PUT HIGH TEMPS IN
THE 20S MOST EVERYWHERE WITH SOME UPPER TEENS IN THE MOUNTAINS.
THIS IS A GOOD 20 DEGREES BELOW NORMAL. SNOW SHOWERS WILL BE
LIKELY IN THE MOUNTAINS WITH 1 TO 3 INCHES POSSIBLE. FOR SUNDAY
NIGHT WINDS WILL ABATE SOMEWHAT AFTER MIDNIGHT BUT TEMPS WILL
PLUNGE. EXPECT AROUND ZERO IN THE MOUNTAINS AND NEAR 10 AT THE
COAST. RECORD LOW FOR PORTLAND MONDAY IS 9 DEGREES. WILL BE CLOSE
TO THIS.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
RIDGE OF HIGH PRESSURE WILL CREST OVER THE REGION MONDAY BEFORE
SHIFTING OFFSHORE. EXPECT A SUNNY START TO THE DAY BEFORE HIGH
CLOUDS SPILL IN FROM THE WEST IN THE AFTERNOON. WILL BE ANOTHER COLD
ONE WITH HIGHS ONLY REACHING THE UPPER TEENS TO LOWER 20S NORTH AND
MID 20S TO NEAR 30 SOUTH.
AREA OF WEAK OVER-RUNNING AHEAD LOW PRESSURE MOVING THROUGH SOUTHERN
CANADA WILL PUSH IN FROM THE WEST MONDAY NIGHT BRINGING SOME LIGHT
SNOW TO THE REGION. BEST CHANCES OF PRECIP WILL BE IN NORTHERN ZONES
WHERE AN INCH OR TWO OF ACCUMULATION WILL BE POSSIBLE. ELSEWHERE
JUST LOOKING FOR A LIGHT DUSTING. LOOKING FOR LOWS IN THE MID TEENS
TO LOWER 20S.
CLOUDS AND LINGERING FLURRIES WILL GIVE WAY TO PARTLY SUNNY SKIES ON
TUESDAY. COLD FRONT APPROACHING FROM THE WEST MAY BRING SNOW SHOWERS
TO THE MOUNTAINS BY LATE IN THE DAY. SHOULD SEE A MUCH WARMER DAY
WITH TEMPS RANGING THROUGH THE 30S.
COLD FRONT WILL SWING THROUGH THE REGION TUESDAY NIGHT BRINGING A
CHANCE OF SNOW SHOWERS IN THE NORTH AND VARIABLE CLOUDS ACROSS
SOUTHERN AREAS. OVERNIGHT LOWS WILL RANGE THROUGH THE 20S.
MODELS STILL FAR APART ON WEDNESDAY WITH THE ECMWF BRINGING LOW
PRESSURE UP THE EAST COAST AND GFS TAKING THE SAME SYSTEM WELL
OFFSHORE. AT THIS POINT SUPER BLEND GIVING LIKELY POPS WITH A MIX OF
RAIN AND SNOW IN THE SOUTH AND SNOW IN THE FOOTHILLS AND NORTH. SO
POTENTIAL IS STILL THERE FOR SIGNIFICANT SNOW IN THE NORTH AND A
MESSY MIX IN THE SOUTH. HIGH TEMPS WILL RANGE THOUGH THE 30S TO
NEAR 40.
HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE WEST THURSDAY
THROUGH FRIDAY. EXPECT TEMPS ONCE AGAIN BELOW NORMAL THURSDAY AS
COLD CANADIAN AIR FLOODS IN ON A STRONG NORTHERLY WINDS. WILL SEE
TEMPS MODERATE SOMEWHAT ON FRIDAY AS HIGH PRESSURE CRESTS OVER THE
REGION.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...EXPECT MOSTLY VFR. BRIEF MVFR/IFR PSBL LATE TONIGHT
IN SNOW SHOWERS. HIE WILL SEE MOSTLY MVFR.
LONG TERM...VFR MONDAY THROUGH TUESDAY. IFR/LIFR CEILINGS AND VSBY
DEVELOPING ON WEDNESDAY. VFR THURSDAY.
&&
.MARINE...
SHORT TERM...GALE WARNING HAS BEEN ISSUED.
LONG TERM...GALES POSSIBLE ON WEDNESDAY.
&&
.CLIMATE...
SIGNIFICANT OUTBREAK OF EARLY SEASON COLD AIR WILL CHALLENGE SOME
LOCAL RECORDS OVER THE NEXT COUPLE OF DAYS. AT KPWM THE RECORD
COLD MAXIMUM TEMP FOR 11/24 IS 28 SET IN 1989. THE TEMP AROUND
MIDNIGHT TONIGHT WILL LIKELY BE THE WARMEST KPWM GETS ALL
DAY...AND WILL BE VERY CLOSE TO 28 DEG. ON 11/25 KPWM HAS A RECORD
COLD MAXIMUM TEMP OF 29 SET IN 1993. THE CURRENT FORECAST IS FOR A
HIGH TEMP AROUND 30. FOR LOW TEMP ON 11/25...KPWM SET A RECORD IN
2000 OF 9 DEG. THE CURRENT FORECAST IS FOR 11/25 IS A LOW TEMP
AROUND 10 DEG.
A LITTLE COOLER BUT SIMILARLY FOR KCON...THE RECORD COLD MAXIMUM
TEMP FOR 11/24 IS 24 SET IN 1921. WHILE IN 1938 THE RECORD COLD
MAXIMUM TEMP FOR 11/25 WAS SET AT 21. THE RECORD LOW TEMP FOR
11/25 IS 5 DEG SET IN 1956 AND 2000.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WIND ADVISORY UNTIL 1 AM EST MONDAY FOR MEZ007>009-012>014-
018>028.
NH...WIND ADVISORY UNTIL 1 AM EST MONDAY FOR NHZ001>010-013-014.
MARINE...GALE WARNING UNTIL 7 AM EST MONDAY FOR ANZ150>154.
&&
$$
ES
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
343 AM CST SUN NOV 24 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 323 AM CST SUN NOV 24 2013
1045 MB ARCTIC HIGH PRESSURE CENTERED NEAR KANSAS CITY WILL MOVE
RAPIDLY EAST THROUGH THE MIDSOUTH TODAY AND BE LOCATED OVER NORTH
CAROLINA BY MONDAY MORNING.
THE MODELS INSIST STRATUS WILL FORM IN THE RETURN FLOW SETTING
ACROSS SWRN NEB. AT 08Z THE NEAREST STRATUS WAS OVER NW TEX...ABOUT
500 MILES SOUTH OF THE FORECAST POSITION OF THE MODEL CONSENSUS. NO
STRATUS IS EXPECTED TO DEVELOP AT THIS TIME BUT MID LEVEL CLOUDS
ACROSS ERN COLO/WRN KS ARE EXPECTED TO LIFT NORTH PART WAY THROUGH
THE FCST AREA AND THEN GET SHUNTED EAST WITH THE APPROACH OF A NRN
STREAM SHORTWAVE THIS EVENING. TEMPERATURES ARE EXPECTED TO RISE
INTO THE 30S TO AROUND 40. WARMER GUIDANCE WAS USED FOR THE FORECAST
OWING TO THE CONTAMINATION IN THE SKY COVER SHOWN BY MOST MODELS.
FOR TONIGHT A COLD FRONT WILL BE MOVING SOUTH THROUGH THE NRN HIGH
PLAINS. A THERMAL RIDGE WILL BE RUNNING OUT AHEAD OF THE COLD FRONT
WHICH WILL LIKELY PRODUCE THE COOLEST LOWS IN THE SOUTH BEFORE THE
WIND SHIFT DEVELOPS LATE TONIGHT. THUS LOWS IN THE TEENS ARE
EXPECTED SOUTH WITH 20S NORTH.
SOUTH AND SOUTHWEST WINDS TODAY INCREASE TO 15 TO 25 MPH. LOW
PRESSURE CURRENTLY ACROSS GREAT SLAVE LAKE WILL DIVE SOUTHEAST
TOWARD LAKE SUPERIOR TODAY AND TONIGHT. THE 500M AGL WINDS IN THE
NAM AND RAP MODELS INCREASE TO NEAR 30 MPH AT THE SFC EAST OF
HIGHWAY 183. THIS WOULD SUPPORT GUSTS TO 35 MPH BUT LIMITED VERTICAL
MIXING IN COOL RETURN FLOW SHOULD LIMIT SUSTAINED WIND SPEEDS TO 25
MPH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 323 AM CST SUN NOV 24 2013
A SLOW MOVING UPPER LEVEL LOW PRESSURE SYSTEM WILL MIGRATE FROM
ARIZONA TO WEST TEXAS BY MONDAY. MEANWHILE ANOTHER POTENT
SHORTWAVE TROUGH WILL DIVE SOUTHEAST THROUGH CENTRAL
CANADA...REACHING THE GREAT LAKES BY TUESDAY EVENING. THE
SOUTHERN PLAINS LOW AND GREAT LAKES TROUGH WILL EVENTUALLY
PHASE TO OUR EAST...AND BRING HEAVY PRECIPITATION ALONG THE EAST
COAST WEDNESDAY AND WEDNESDAY NIGHT. AS MENTIONED...THE MAJORITY
OF THE WEATHER WITH THESE SYSTEMS REMAINS TO OUR EAST...BUT A COLD
FRONT WILL DROP SOUTH THROUGH THE AREA TUESDAY. THIS WILL BRING
ANOTHER REINFORCING SHOT OF ARCTIC AIR TO THE REGION. THE BRUNT OF
THE ARCTIC AIR WILL BE FELT ACROSS THE MISSOURI RIVER
VALLEY...WHERE HIGHS IN THE 20S ARE EXPECTED. FARTHER WEST ACROSS
THE HIGH PLAINS OF WESTERN NEBRASKA AND EASTERN COLORADO...THE
COLD FRONT WILL HAVE LITTLE IMPACT...WITH A PACIFIC AIRMASS AND
HIGHS IN THE 40S REMAINING IN PLACE.
BY MID TO LATE WEEK...UPPER LEVEL RIDGING WILL BUILD EAST ACROSS
THE CENTRAL CONUS. WARMER PACIFIC AIR WILL ALSO SPREAD EAST...WITH
HIGHS IN THE UPPER 30S TO MID 40S REGION WIDE. LITTLE
PRECIPITATION IS EXPECTED...AS ATMOSPHERIC MOISTURE REMAINS
LIMITED THROUGH THE END OF THE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1147 PM CST SAT NOV 23 2013
UPPER LEVEL LOW PRESSURE WILL TRACK ACROSS THE SOUTHERN ROCKIES
INTO THE SOUTHERN PLAINS OVER THE NEXT 24 HOURS. THIS FEATURE WILL
SPREAD ABUNDANT HIGH CLOUDS INTO SOUTHERN NEBRASKA
TONIGHT...FOLLOWED BY SOME LOW LEVEL CLOUDINESS ON SUNDAY. AT THIS
TIME...LOW LEVEL CLOUDINESS WITH CIGS BETWEEN 3000 AND 5000 FT AGL
WILL BE POSSIBLE AT THE KLBF TERMINAL SUNDAY MORNING THROUGH
SUNDAY EVENING. AT THE KVTN TERMINAL...SKIES WILL BE CLEAR TONIGHT
WITH SOME SCATTERED TO BROKEN HIGH CLOUDS AON 25000 FT AGL
POSSIBLE AFTER 16Z SUNDAY. WINDS WILL BE FROM THE SOUTH AT 5 TO 10
KTS TONIGHT...INCREASING TO 15 TO 25 KTS SUNDAY...DIMINISHING BACK
TO AROUND 10 KTS SUNDAY EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
910 PM PST SAT NOV 23 2013
.SYNOPSIS...RAIN AND SNOW SHOWERS WILL CONTINUE TONIGHT AS A LOW
PRESSURE SYSTEM MOVES EAST ACROSS FAR SOUTHERN CALIFORNIA. GRADUAL
CLEARING IS EXPECTED FROM WEST TO EAST SUNDAY AS THE STORM SYSTEM
TRACKS INTO WESTERN NEW MEXICO. DRY AND WARMER CONDITIONS CAN BE
EXPECTED MONDAY THROUGH WEDNESDAY AS HIGH PRESSURE TRAVERSES THE
REGION. THE NEXT STORM SYSTEM MAY BRING A CHANCE OF SHOWERS TO
PORTIONS OF THE AREA FROM LATE THANKSGIVING DAY INTO FRIDAY.
&&
.UPDATE...OVERALL RADAR RETURNS ARE ON A DOWNWARD TREND THIS EVENING
ALTHOUGH SOME ACTIVITY IS PROBABLY BEING OVERSHOT BY THE RADAR.
BASED ON THE LATEST RADAR AS WELL AS THE LATEST HRRR MODEL AND 00Z
REGIONAL WRF, I HAVE GONE AHEAD AND MADE SOME MINOR ADJUSTMENTS TO
POPS TO FIT THE LATEST TRENDS SUGGESTED BY THESE TOOLS. THE MAIN
ISSUE FOR LAS VEGAS FOR THE REST OF TONIGHT WILL BE HOW MUCH
MOISTURE WRAPPING AROUND THE BACK SIDE OF THE UPPER LOW IS ABLE TO
SQUEEZE OUT ANY ADDITIONAL SHOWER ACTIVITY. IT APPEARS BY MIDNIGHT
WE SHOULD BE DONE WITH ANY SHOWERS FOR THE MOST PART AS FORECAST
SOUNDINGS FROM THE RAP AND WRF ALL SHOW THE LOWER-LEVELS STARTING TO
DRY OUT. I WILL LEAVE ANY WINTER WEATHER PRODUCTS OUT AS THESE AREAS
MAY SEE ANOTHER INCH OR TWO OF SNOW AND DEAL WITH THEM WITH THE
MORNING PACKAGE BASED ON HOW THINGS TREND.
AS FOR FOG TONIGHT, THERE MAY BE SOME IN THE HIGHER ELEVATIONS ALONG
THE SLOPES WHERE THE CLOUD BASES ARE AT GROUND LEVEL, BUT IT LOOKS
UNLIKELY IN THE LOWER ELEVATIONS AS THE LOW LEVELS HAVE EITHER
REALLY DRIED OUT (AS IN BISHOP WHERE DEWPOINTS HAVE DROPPED TO 11F)
OR ENOUGH STRATUS REMAINS RIGHT NOW THAT THINGS DO NOT APPEAR THEY
WILL CLEAR OUT TO ALLOW ANY FOG TO DEVELOP. FORECAST SOUNDINGS FOR
BISHOP AND DAGGETT FROM THE RAP AND WRF BOTH CONFIRM THIS AND ANY
FOG WAS YANKED FROM THE GRIDS WITH THIS UPDATE. OTHERWISE THE
FORECAST LOOKS IN GOOD SHAPE AS WE LOOK TOWARD A DRIER AND NOT AS
DAMP SUNDAY FOR THE AREA.
&&
.AVIATION...FOR MCCARRAN...THE MAIN ISSUE OVERNIGHT WILL BE WITH
CIGS AS OVERALL RADAR TRENDS WOULD ONLY SUPPORT A FEW LIGHT RAIN
SHOWERS IN AND AROUND THE LAS VEGAS VALLEY THROUGH 08Z SUNDAY OR SO.
CIGS INITIALLY SHOULD BE AROUND 4K FEET OR SO...BUT AS SHOWER
ACTIVITY ENDS AND SOME SLIGHT DRYING OF THE LOWER LEVELS OF THE
ATMOSPHERE TAKES PLACE...LOWER CLOUD BASES SHOULD BECOME MORE IN THE
SCT-BKN RANGE AND ANY BKN-OVC CLOUD BASES SHOULD BE MORE IN THE
15-20K FOOT RANGE FOR THE DURATION OF TONIGHT. FURTHER DRYING SHOULD
TAKE PLACE ON SUNDAY WITH MAINLY SCT-BKN CLOUDS AOA 5K-8K FEET.
CLOUDS SHOULD BE EXTENSIVE ALONG THE EDGES OF THE VALLEY WITH
MOUNTAIN OBSCURATIONS LIKELY OVERNIGHT THROUGH 18Z OR SO SUNDAY.
WINDS SHOULD FAVOR TYPICAL DIURNAL TRENDS ON SUNDAY AT SPEEDS OF 5
KTS OR LESS.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...MAINLY MVFR CIGS TONIGHT WHERE ANY THICKER CLOUD
COVERAGE EXISTS WITH VSBY MAINLY IN THE VFR RANGE AWAY FROM ANY
SHOWERS. LOWER VSBY EXPECTED IN ANY SNOW SHOWERS. SHOWERS SHOULD
DECREASE IN COVERAGE OVERNIGHT AND BE DONE ACROSS ALL AREAS EXCEPT
EASTERN MOHAVE COUNTY BY 18Z SUNDAY AND ANY LINGERING SHOWERS THERE
SHOULD END BY 21Z SUNDAY OR SO. SCT-BKN CLOUDS AOA 5K-8K FEET
OTHERWISE ON SUNDAY WITH VFR VSBY. WINDS OVERALL SHOULD BE 10 KTS OR
LESS WITH SPEEDS TRENDING TOWARDS TYPICAL DIURNAL COMPONENTS OR A
NORTHERLY DIRECTION.
&&
.PREVIOUS DISCUSSION...
ISSUED AT 240 PM PST SAT NOV 23 2013
.DISCUSSION...RAIN AND SNOW CONTINUED ACROSS THE AREA THIS
AFTERNOON AS THE STRONG UPPER LOW WAS MOVING INLAND ALONG THE MEXICO
BORDER. SIX HOUR RAINFALL AMOUNTS ENDING AT 220 PM HAVE BEEN
GENERALLY FROM A TENTH TO A QUARTER OF AN INCH ACROSS CLARK AND
MOHAVE COUNTIES WITH SOMEWHAT LIGHTER AMOUNTS IN MOST OTHER AREAS.
WEB CAMS SHOWED CLOUDS AND SNOWFALL LIFTING IN INYO COUNTY AND THE
WINTER WEATHER ADVISORY WILL BE ALLOWED TO EXPIRE AT 4 PM. THE
ADVISORIES FOR THE SPRING MOUNTAINS AND SHEEP RANGE AND FOR HIGHER
ELEVATIONS OF SOUTHERN MOHAVE COUNTY REMAINS IN EFFECT UNTIL 10 AM
SUNDAY. THE UPPER LOW WILL MOVE INTO ARIZONA LATE TONIGHT WITH
PRECIPITATION CHANCES ENDING IN THE WESTERN PART OF THE FORECAST
AREA WHILE CONTINUING IN THE EAST. I KEPT A MENTION OF FOG IN THE
FORECAST TONIGHT IN SOME AREAS BUT IF CLOUDS DO NOT CLEAR OUT SOME
THE FOG MAY NOT DEVELOP. THE MOST LIKELY PLACES FOR FOG FORMATION
TONIGHT WILL BE IN THE VALLEYS OF INYO COUNTY AND IN WESTERN SAN
BERNARDINO COUNTY. AS THE LOW CENTER MOVES JUST INTO WESTERN NEW
MEXICO LATE SUNDAY...SOME CLEARING WILL DEVELOP WITH PRECIPITATION
ENDING BY THE AFTERNOON EXCEPT FOR PERHAPS MOHAVE COUNTY.
THE MODELS ARE STILL IN GOOD AGREEMENT WITH A RIDGE OF HIGH PRESSURE
TRAVERSING THE AREA MONDAY THROUGH WEDNESDAY LEADING TO DRY
CONDITIONS AND A WARMING TREND. THE MODELS STILL DIFFER IN THE
HANDLING OF THE NEXT UPPER LOW. AT THIS TIME IT LOOKS LIKE IT WILL
PROBABLY MOVE ROUGHLY TO THE CENTRAL CALIFORNIA COAST LATE THURSDAY
WITH PRECIPITATION CHANCES SPREADING ACROSS MAINLY INYO COUNTY.
THERE IS POTENTIAL FOR THE LOW TO MOVE FARTHER INLAND FRIDAY AND I
KEPT A SLIGHT CHANCE OF SHOWERS OVER MOST OF THE FORECAST AREA
EXCEPT MOHAVE COUNTY. CONFIDENCE IS LOW AS THE ECMWF REMAINS MUCH
LESS PROGRESSIVE WITH THE LOW. BY FRIDAY THE LOW MAY HAVE EITHER
WEAKENED SIGNIFICANTLY OR DROPPED OFF SHORE LEADING TO DRY
CONDITIONS OVER OUR FORECAST AREA. AGAIN...CONFIDENCE IS LOW.
&&
.VEF WATCHES/WARNINGS/ADVISORIES...
NV...WINTER WEATHER ADVISORY UNTIL 10 AM PST SUNDAY FOR NVZ018-019.
AZ...WINTER WEATHER ADVISORY UNTIL 11 AM MST SUNDAY FOR AZZ003.
CA...NONE.
&&
$$
UPDATE/AVIATION...STACHELSKI
PREVIOUS...HARRISON
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1139 PM EST SAT NOV 23 2013
.SYNOPSIS...
LAKE EFFECT SHOWERS WILL INITIATE IN THE WAKE OF THE COLD FRONT
TONIGHT. HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE EAST
ON SUNDAY AND PERSIST THROUGH MONDAY. A COLD FRONT WILL MOVE
ACROSS THE AREA LATE MONDAY NIGHT INTO TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
I WILL CONTINUE WITH THE CURRENT FORECAST TREND. THE HRRR MODEL
SEEMS TO BE HANDLING THE CURRENT LAKE EFFECT SITUATION WELL. IT
SHOWS TWO MAIN BANDS...ONE OVER NW PA AND ONE JUST EAST OF CLE.
THE RADAR SHOWS THIS TREND. THE MODEL SHOWS THE BAND EAST OF CLE
WEAKENING AFTER 06Z WITH THE BANDS OVER NW PA BECOMING DOMINATE.
THE WARNED AREA LOOKS GOOD. I AM A LITTLE UNEASY ABOUT
LAKE...GEAUGA...EASTERN CUYAHOGA AND THE NORTHERN SECTIONS OF
PORTAGE AND SUMMIT. CURRENT FORECAST OF 2 TO 4 INCHES LOOKS
REASONABLE BUT VALUES COULD CLIMB TO NEAR LAKE EFFECT ADVISORY
LEVELS IF THE BAND EAST OF CLEVELAND PERSISTS. I WILL CONTINUE
TO MONITOR BUT AN ADVISORY WILL NOT BE ISSUED WITH THIS UPDATE.
PREVIOUS DISCUSSION...
THE COLD FRONT IS CURRENTLY SOUTHEAST OF THE AREA. TEMPERATURES
WILL CONTINUE TO DROP STEADILY BEHIND THE FRONT DUE TO STRONG COLD
AIR ADVECTION. COLDER TEMPERATURES WILL LEAD TO EXTREME
INSTABILITY OVER LAKE ERIE...INITIATING LAKE EFFECT SNOW. THERE IS
STILL SOME QUESTION AS TO HOW STRONG THE LAKE EFFECT SNOW WILL
BECOME. 850 MB TEMPERATURES AROUND 25C WILL PROVIDE ENOUGH
INSTABILITY TO PRODUCE HEAVY SNOW...BUT MOISTURE WILL BE LIMITED
DUE TO SHORT FETCH WITH NORTHWEST WINDS. ONE WAY TO GET ADDED
MOISTURE IS FOR THE LAKE EFFECT TO DEVELOP A CONNECTION TO ANOTHER
LAKE. MODELS ARE HINTING AT A LAKE HURON CONNECTION WITH THIS
EVENT AND IF THAT OCCURS WE MAY GET THE ADDED MOISTURE NECESSARY
TO REALLY GET THINGS GOING.
SNOW ACCUMULATIONS ARE ALSO A BIT TRICKY AND DEPEND ON WHETHER OR
NOT WE GET THAT LAKE HURON CONNECTION. ASSUMING WE GET THE
CONNECTION...WE COULD SEE ANYWHERE FROM SIX INCHES TO OVER A FOOT
OF SNOW OVER EXTREME NORTHEAST OHIO AND NORTHWEST PENNSYLVANIA. THE
AREAS MOST LIKELY TO SEE OVER A FOOT OF SNOW ARE THE IN THE HIGHER
TERRAIN OF NORTHWEST PENNSYLVANIA WHERE UPSLOPE FLOW WILL ENHANCE
THE LAKE EFFECT SNOW. SEVERAL SECONDARY BANDS MAY DEVELOP TO THE
WEST OF THE PRIMARY BAND. THE SECONDARY BANDS DO NOT LOOK LIKE THEY
WILL PRODUCE ENOUGH SNOW TO REACH ADVISORY CRITERIA. THE EVENING
SHIFT WILL CONTINUE TO MONITOR THE SITUATION AS IT EVOLVES AND ISSUE
AN ADVISORY IF THEY BELIEVE IT TO BE NECESSARY.
AS FOR TEMPERATURES TONIGHT...COLD AIR ADVECTION WILL CONTINUE
OVERNIGHT WITH OVERNIGHT LOWS REACHING INTO THE TEENS FOR MANY
LOCATIONS.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
HIGH PRESSURE WILL MOVE EAST INTO THE AREA ON SUNDAY...HELPING TO
TAPER THE LAKE EFFECT SNOW SUNDAY EVENING. WE WILL GET A BRIEF
RESPITE FROM THE SNOW ON MONDAY AS THE HIGH PRESSURE SLIDES EAST.
A COLD FRONT WILL CROSS THE AREA LATE MONDAY NIGHT INTO TUESDAY
MORNING. NOT EXPECTING MUCH IN THE WAY OF SNOW WITH THE FRONTAL
PASSAGE. FOR NOW...GOING WITH A CHANCE OF SNOW SHOWERS FOR MOST OF
THE FORECAST AREA.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
COLD AND MAINLY QUIET WEATHER IS EXPECTED DURING THE LONG TERM
PERIOD. SOME LAKE EFFECT IS POSSIBLE TUESDAY NIGHT INTO WEDNESDAY
BUT WINDS QUICKLY BECOME UNFAVORABLE ON WEDNESDAY EVENING. IT
APPEARS THAT MOST OF THE LAKE EFFECT WILL BE NUISANCE TYPE
ACTIVITY AND AM NOT ANTICIPATING ANY HEADLINES. THURSDAY THROUGH
SATURDAY LOOK TO BE DRY. HIGH TEMPS DURING THE PERIOD WILL
CONTINUE TO BE 10 TO 15 DEGREES BELOW NORMAL.
&&
.AVIATION /04Z SUNDAY THROUGH THURSDAY/...
LIMITED LAKE EFFECT WITH REALLY DRY AIR WORKING INTO THE AREA.
DEWPOINTS ARE IN THE SINGLE DIGITS. ERIE AND VICINITY WILL HAVE
THE HEAVIEST LAKE EFFECT AS A LAKE EFFECT SNOW BAND WITH
CONNECTIONS TO LAKE HURON WOBBLES BETWEEN THE OH/PA BORDER AND
ERI. THIS WILL PRODUCE PREDOMINATELY IFR CONDITIONS. OUTSIDE OF
THIS BAND SNOW SHOWERS ARE HIT OR MISS AND WITH NON VFR CONDITIONS
BRIEF AND TEMPORARY. GUSTS FROM CLE/CAK EASTWARD WILL CONTINUE
OVERNIGHT TO BE AROUND 25 KTS TO OCCASIONALLY 30 KNOTS. FOR SUNDAY
HIGH PRESSURE BEGINS TO BUILD INTO THE OHIO VALLEY...TAPERING THE
LAKE EFFECT FURTHER AND DIMINISHING WINDS AND BRINGING THEM AROUND
TO THE WEST. FAR EASTERN SITES WILL SEE THIS TAKE PLACE NEAR OR
AFTER 00Z MON. LARGELY VFR SUNDAY...WITH THE EXCEPTION OF THE
LIMITED LAKE EFFECT ACROSS FAR NE OH/NW PA.
OUTLOOK...NON VFR MAINLY OVER NE OH AND NW PA SUNDAY NIGHT
BECAUSE OF LAKE EFFECT. MORE WIDESPREAD SYNOPTIC SNOW EXPECTED
LATE MONDAY NIGHT INTO TUESDAY AND CONTINUING ACROSS NE OH/NW PA
ON WEDNESDAY IN LAKE EFFECT SHSN...AND THEREFORE NON-VFR
CONDITIONS.
&&
.MARINE...
HAVE ISSUED THE GALE WARNING FOR THE CENTRAL AND EASTERN PORTIONS
OF LAKE ERIE. WINDS QUICKLY RAMPED UP ABOVE 30 KNOTS AND HAVE BEEN
GALE FORCE. THE OUTLOOK FOR THE REMAINDER OF THE NIGHT IS LOW END
GALES...DIMINISHING SUNDAY MORNING. THE FLOW WILL FINALLY BECOME
WEST SUNDAY EVENING AND THEN SW BY DAYBREAK MONDAY AS HIGH
PRESSURE BUILDS IN FROM THE SOUTH. SOUTHWEST FLOW IS EXPECTED TO
CONTINUE TILL ANOTHER COLD FRONT CROSSES THE LAKE ON TUESDAY. THIS
WILL BRING MORE CHANCES FOR PRECIP AND NW FLOW BACK TO THE LAKE.
WINDS WILL BECOME NORTHERLY ON WEDNESDAY AND NE ON THURSDAY S
ARCTIC HIGH PRESSURE BUILDS IN FROM THE NORTH.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...LAKE EFFECT SNOW WARNING UNTIL MIDNIGHT EST SUNDAY NIGHT FOR
OHZ014-089.
PA...LAKE EFFECT SNOW WARNING UNTIL MIDNIGHT EST SUNDAY NIGHT FOR
PAZ001>003.
MARINE...GALE WARNING UNTIL 4 AM EST SUNDAY FOR LEZ061-146>149-166>169.
SMALL CRAFT ADVISORY UNTIL 11 AM EST TUESDAY FOR LEZ142>145.
&&
$$
SYNOPSIS...SCHEPEL
NEAR TERM...GARNET
SHORT TERM...SCHEPEL
LONG TERM...KUBINA
AVIATION...OUDEMAN
MARINE...KUBINA/OUDEMAN
AREA FORECAST DISCUSSION
NWS GOODLAND KS
451 AM MST SUN NOV 24 2013
.SHORT TERM...(TODAY AND TUESDAY NIGHT)
ISSUED AT 149 AM MST SUN NOV 24 2013
THE UPPER LEVEL LOW PRESSURE SYSTEM EXPECTED TO AFFECT THE
FORECAST AREA WILL MOVE SLOWLY ACROSS THE DESERT SOUTHWEST AND
SOUTHERN ROCKIES TODAY. AHEAD OF THIS SYSTEM...LIGHT SNOW WILL
SPREAD NORTHWARD OUT OF EASTERN NEW MEXICO AND THE PANHANDLE
REGION OF TEXAS AND OKLAHOMA INTO PORTIONS OF EASTERN COLORADO AND
WESTERN KANSAS. THE BEST CHANCE OF ACCUMULATING SNOWFALL WILL BE
THIS MORNING MAINLY ALONG AND SOUTH OF INTERSTATE 70 WHERE AN INCH
OR LESS OF TOTAL ACCUMULATION IS POSSIBLE.
THE UPPER LOW CENTER WILL PHASE INTO THE MAIN UPPER TROUGH THAT
DEEPENS OVER THE GREAT LAKES AND MISSISSIPPI VALLEY REGION
TONIGHT. THE LOW WILL THEN BEGIN TO MOVE SOUTHEASTWARD OVER TEXAS
WITH DRYER AIR ALOFT AND SUBSIDENCE MOVING OVER THE CENTRAL HIGH
PLAINS REGION TONIGHT. THE UPPER RIDGE AMPLIFYING OVER THE WESTERN
UNITED STATES MOVES OVER THE INTERMOUNTAIN REGION MONDAY NIGHT AND
TUESDAY AND BEGINS TO MOVE OVER THE ROCKIES ON TUESDAY NIGHT.
ALTHOUGH TEMPERATURES WILL BE GRADUALLY INCREASING THROUGH THE
FIRST PART OF THE WORK WEEK AS HIGH PRESSURE MOVES INTO THE
REGION...MODEL TRENDS HAVE BEEN CONSISTENTLY LOWERING TEMPERATURES
WITH EACH SUBSEQUENT MODEL RUN OVER THE PAST FEW DAYS. TEMPERATURES
WILL REMAIN COLDER THAN AVERAGE WITH DRY CONDITIONS EXPECTED.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 149 AM MST SUN NOV 24 2013
THE LARGE SCALE PATTERN SHOWS A LONGWAVE TROUGH OVER THE EASTERN
PORTION OF THE U.S. WITH AN UPPER RIDGE OVER THE ROCKIES.
THROUGHOUT THE EXTENDED...SEVERAL SHORTWAVE TROUGHS IN THE
NORTHWEST/WESTERLY FLOW ALOFT MOVE THROUGH THE NORTHERN
PLAINS...SENDING A FEW WEAK COLD FRONTS THROUGH THE CWA. THE COLD
AIR BEHIND THE FIRST FRONT IS KEPT WELL TO THE NORTH...SO
TEMPERATURES ARE NOT EXPECTED TO FLUCTUATE MUCH BEHIND THE FRONTAL
PASSAGE. THE FIRST FRONT MOVES THROUGH WEDNESDAY NIGHT INTO
THURSDAY AND THE NEXT FRONT...ASSOCIATED WITH WESTERLY/SOUTHWEST
FLOW ALOFT...MOVES THROUGH FRIDAY NIGHT INTO SATURDAY.
TEMPERATURES WITH THE NEXT FRONTAL PASSAGE ALSO ARE NOT EXPECTED
TO FLUCTUATE MUCH SINCE HIGHS SHOULD RECOVER AS THE SURFACE HIGH
QUICKLY PUSHES EAST BY SATURDAY AFTERNOON. FRONTAL PASSAGES WILL
ALSO REMAIN DRY AS THE MAIN FORCING WITH THESE WAVES ALSO REMAINS
NORTH OF THE CWA. TOWARDS THE END OF THE PERIOD...THE LARGE SCALE
PATTERN SHIFTS EAST WITH THE RIDGE FLATTENING AND MOVING OVER THE
CWA THURSDAY THROUGH SATURDAY...WHILE A CLOSED UPPER LOW REMAINS
OVER SOUTHERN CALIFORNIA AND SLOWLY MOVES EAST/SOUTHEAST WITH THE
SOUTHERN STREAM JET MOVING OVER THE CWA ON SATURDAY.
AS PREVIOUSLY MENTIONED...THE EXTENDED PERIOD SHOULD REMAIN
DRY...WITH INCREASING MID TO HIGH CLOUDS WITH FRONTAL PASSAGES.
TEMPERATURES SHOULD REMAIN SEASONABLE...WITH HIGHS IN THE MID 40S TO
LOW 50S AND LOWS IN THE 20S. ONCE EXCEPTION FOR HIGH TEMPERATURES
WILL BE WEDNESDAY...AS SURFACE HIGH PRESSURE OVER EASTERN KANSAS
EXTENDS INTO THE EASTERN PORTION OF THE CWA...FROM RED WILLOW TO
GOVE COUNTY AND EASTWARD...HIGHS COULD ONLY REACH THE UPPER 30S TO
LOW 40S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 440 AM MST SUN NOV 24 2013
CURRENTLY IT LOOKS LIKE VFR CONDITIONS WILL PREVAIL THROUGH THE
TAF PERIOD. CEILINGS AT KGLD ONLY REDUCED TO BKN060 IN THE LAST
FEW HOURS AS THE FIRST WEAK BAND OF LIGHT SNOW MOVED OVER THE TAF
SITE. SOUNDINGS EARLIER THIS MORNING INDICATED POSSIBLY LOWER
CEILINGS WITH A CONTINUING CHANCE OF LIGHT SNOW LATER THIS
MORNING. AFTER VIEWING RAP SOUNDINGS...IT APPEARS THAT THIS IS NO
LONGER THE CASE. GUIDANCE ALSO DID NOT INCLUDE LOWERED CEILINGS
BEYOND VFR. LOW CONFIDENCE IN THE FORECAST AS OF RIGHT NOW...WILL
MAKE ANY AMMENDMENTS IF AND WHEN NECESSARY. SOUTHERLY WINDS WILL
PICK UP TODAY TO AROUND 15 TO 25 KTS GUSTING FROM 25 TO 35 KTS.
WIND GUSTS SHOULD DIMINISH OVERNIGHT WITH A WIND SHIFT TO THE
NORTHWEST. OVERCAST AND BROKEN CEILINGS SHOULD BECOME SCATTERED
OVERNIGHT AS THE THE STORM SYSTEM SOUTH OF THE AREA MOVES
NORTH/NORTHEAST.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...LOCKHART
LONG TERM...ALW
AVIATION...ALW
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
659 AM EST SUN NOV 24 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 526 AM EST SUN NOV 24 2013
WV IMAGERY AND RUC ANALYSIS INDICATED NW MID/UPPER LEVEL FLOW
THROUGH THE NRN GREAT LAKES WITH GRADUALLY RISING HEIGHTS AS THE
TROUGH OVER THE NE CONUS SLIDES TO THE EAST AND MID LEVEL RIDGING
BUILDS TOWARD THE AREA FROM SOUTH CENTRAL CANADA. AT THE SFC...A
RIDGE WAS BUILDING FROM NW WI AND WRN LAKE SUPERIOR INTO FAR W UPPER
MI WHILE LAKE INDUCED TROUGHING PREVAILED THROUGH ERN LAKE SUPERIOR.
SATELLITE AND RADAR INDICATED NW-SE ALIGNED WIND PARALLEL LES BANDS
HAD SHIFTED INTO LOCATIONS E OF MARQUETTE COUNTY. THE BANDS HAD
ALSO BECOME MORE CELLULAR WITH GRADUALLY DECREASING INTENSITY
OVERNIGHT. SFC OBS STILL INDICATED INTO W UPPER MI WITH CMX SHOWING
VSBY IN THE 1-3SM RANGE. HOWEVER...WEBCAMS FROM HOUGHTON AND CALUMET
SHOWED LITTLE SNOW OR VSBY REDUCTION.
THIS MORNING...
DESPITE 850 MB TEMPS AROUND -20C...INVERSION HEIGHTS DROPPING BELOW
5K FT AND VERY DRY AIR UPSTREAM WILL CONTINUE TO LIMIT LES
INTENSITY...ESPECIALLY OVER THE WEST. DIMINISHING WINDS WITH AN
INCREASED LAND BREEZE INFLUENCE AND A BACKING TREND WITH THE
APPROACHING RIDGE WILL RESULT IN A PERIOD OF ENHANCED CONVERGENCE
FROM ERN LAKE SUPERIOR INTO UPPER MI BETWEEN MUNISING AND NEWBERRY
WHERE ADDITIONAL SNOW AMOUNTS IN THE 1 TO 3 INCH RANGE ARE EXPECTED
THROUGH THE MORNING. THE BACKING WINDS SHOULD PUSH THE REMAINING LES
OFFSHORE IN THE AFTERNOON.
THIS AFTERNOON AND TONIGHT...
DEVELOPING WAA WITH STRONG 280K-295K PRES ADV BUT ONLY WEAK TO
MODERATE NET LIFT AHEAD OF A SHRTWV AND SFC LOW MOVING INTO CNTRL
MANITOBA MAY LEAD TO AN AREA OF LIGHT SNOW STREAKING SE INTO THE
NORTH AND EAST PORTIONS OF UPPER MI LATE THIS AFTERNOON AND EVENING.
HOWEVER...WITH THE DRY LOW LEVELS...LITTLE IF ANY SNOW ACCUMULATION
IS EXPECTED WITH ONLY SLIGHT CHANCE POPS INCLUDED. SNOW CHANCES WILL
INCREASE OVERNIGHT AS 700-300 MB QVECTOR CONV AHEAD OF THE SHORTWAVE
MOVES IN BUT SNOW AMOUNTS SHOULD REMAIN LESS THAN A HALF INCH. SW
FLOW LAKE ENHANCEMENT IS LIKELY TO DEVELOP OFF OF LAKE MICHIGAN BUT
THE LOW LEVEL WINDS VEER ENOUGH TO KEEP THE HIGHER SNOW
CHANCES/AMOUNTS TO THE SOUTH AND EAST OF SCHOOLCRAFT AND LUCE
COUNTIES.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 440 AM EST SUN NOV 24 2013
NORTHERN STREAM REMAINS ACTIVE THROUGH THE WEEK KEEPING THE COLD
ACROSS THE GREAT LAKES. NEXT CHARGE OF ARCTIC AIR ARRIVES LATER
MONDAY NIGHT INTO TUESDAY. LK EFFECT SNOW INCREASES MONDAY NIGHT
THROUGH TUESDAY NIGHT. AFTER HIGH PRESSURE RIDGE/SUBSIDENCE BRINGS
DIMINISHING TREND TO LK EFFECT LATER WEDNESDAY...ANOTHER SHORTWAVE
DROPPING THROUGH MAY BRING SOME LGT SNOW FOR THANKSGIVING DAY.
AGREEMENT FALLS OFF BY NEXT WEEKEND WITH THE ECMWF KEEPING A NW FLOW
ALOFT ACROSS GREAT LAKES AND BRINGING ANOTHER CLIPPER THROUGH ON
SATURDAY. GFS IS SLOWER AND MORE DEVELOPED BUT FARTHER NORTH WITH
NEXT TROUGH DROPPING THROUGH BY LATE IN THE WEEKEND.
MODELS IN OKAY AGREEMENT THROUGH 12Z TUESDAY THEN THEY BEGIN TO SHOW
DIFFERENCES. OVERALL THOUGH EVEN THE DISAGREEMENT...SPEED OF INITIAL
SHORTWAVE MOVING THROUGH UPR LAKES...DOES NOT HAVE HUGE IMPACTS ON
THE OVERALL THEME OF FORECAST. GFS ENDS UP BEING QUICKER THAN
ECMWF/NAM AND GEM-NH WITH HANDLING OF INITIAL SHORTWAVE. PLAN IS
THAT ON MONDAY MORNING SHORTWAVE WILL BE NORTH OF LK SUPERIOR WITH
TROUGH AXIS DROPPING ACROSS UPR LAKES. SFC LOW/H85 LOW AND SFC
TROUGH SWINGS ACROSS WESTERN UPR MICHIGAN BY MIDDAY AND INTO THE
EASTERN CWA BY EVENING. MAY SEE LGT LK EFFECT WITH MARGINAL TEMPS
AT INVERSION TOP MOST OF THE DAY OVER THE WEST...BETTER CHANCES WILL
BE LATER ON THOUGH. HINT THAT WEAK WAVE IN THE SOUTHERN STREAM
SLIDES WSW-ENE ACROSS MAINLY SOUTHERN SECTIONS OF WESTERN GREAT
LAKES AND INTERACTS WITH H8-H7 FRONTOGENESIS AND RIGHT ENTRANCE
REGION OF JET FM CNTRL GREAT LAKES TO SOUTHERN QUEBEC MONDAY MORNING
THROUGH MID MONDAY AFTN. SOME LGT SYNOPTIC SNOW MAY SCRAPE LK
MICHIGAN ZONES AND FAR EAST. IF THERE IS ENOUGH LOW-LEVEL MOISTURE
TO START THE DAY...COULD EVEN SEE A BIT OF FZDZ ALONG WI BORDER AS
DEEPER MOISTURE HEADS EAST. LAKE ENHANCEMENT EXPECTED OFF LK
MICHIGAN WITH SW FLOW AS H85 TEMPS ARE AROUND -8C. SHOULD STAY
EAST OF CWA THOUGH AS WINDS ARE FM SW INSTEAD OF SSW OR S. FARTHER
WEST...LK EFFECT SHOULD INCREASE LATER AFTN OVER WESTERN THIRD OF
CWA AS SYNOPTIC LIFT /-DIV-Q AT H7-H5/ FM APPROACHING SHORTWAVE
COMBINES WITH WNW WINDS THROUGH H85 AND TEMPS AT H85 OF -8C YIELDING
DELTA T/S UP TO 12C. INSTABILITY IS MARGINAL AND THUS EXPECT ONLY
MINOR SNOW ACCUMS THROUGH 00Z TUESDAY IN THE WEST.
MONDAY NIGHT INTO TUESDAY HOLDS GREATEST CHANCE FOR MODERATE TO
HEAVY LK EFFECT SNOW SHOWERS. OVERALL EXPECT MOST SNOW TO OCCUR FOR
AREAS FAVORED BY NNW WINDS THROUGH TUESDAY AND THEN SHIFT TO AREAS
FAVORED BY N OR NE WINDS ON TUESDAY NIGHT. UNLIKE THIS LAST EVENT
WHERE SNOWFALL AMOUNTS ENDED UP ON THE LOWER END OF FCST FOR MOST
AREAS...SHORTWAVE/ADDITIONAL SYNOPTIC MOISTURE IS FCST TO IMPACT UPR
LAKES DURING THE TIME OF THE LAKE EFFECT...ESPECIALLY THROUGH
TUESDAY. AT THE LEAST...EXPECT ADVY TYPE SNOWS WILL OCCUR FOR MAINLY
NNW-NW FLOW AREAS MONDAY NIGHT INTO TUESDAY. LACK OF PERSISTENT
UNIDIRECTIONAL FLOW IN LAKE EFFECT CONVECTIVE LAYER WILL LIMIT SNOW
AMOUNTS THOUGH THIS WILL PROBABLY BE OFFSET BY THE SHORTWAVE/DEEPER
MOISTURE. SEEMS LIKE HIGHER TERRAIN FROM IRONWOOD TO ROCKLAND TO
PAINESDALE AND ATLANTIC MINE WILL SEE THE MOST SNOW OVER THE WEST
WHILE FAVORED SNOWBELTS FROM EAST OF MARQUETTE TO NEWBERRY...
INCLUDING MOST OF ALGER COUNTY AND ALONG AND NORTH OF THE SENEY
STRETCH IN SCHOOLCRAFT COUNTY...WILL SEE THE MOST SNOW OVER THE CNTRL
AND EASTERN CWA. UNLIKE THIS LAST EVENT...WINDS SEEM MORE CERTAIN TO
VEER ENOUGH NORTHERLY TO ALLOW FOR LK EFFECT SNOWS TO IMPACT NCNTRL
UPR MICHIGAN /HIGHER TERRAIN OF BARAGA AND MARQUETTE COUNTIES/ LATER
TUESDAY INTO TUESDAY NIGHT AND PERHAPS LINGERING INTO MOST OF
WEDNESDAY. INVERSIONS LOWERING BLO 5KFT AND WINDS BECOMING VARIABLE
WILL DIMINISH SNOW OVER FAR WEST BY WEDNESDAY AFTN. A LIGHT BUT
PERSISTENT N-NE WIND MAY KEEP WEAKENING SNOW SHOWERS GOING THROUGH
MOST OF THE NIGHT BTWN MQT AND MUNISING. LIGHTER WINDS PROBABLY WILL
KEEP MOST OF SNOW SHOWERS RIGHT ALONG IMMEDIATE SHORE WITH SKIES
TRYING TO CLEAR OUT INLAND.
SHORTWAVE AND ARC OF WARM AIR ADVECTION/MOISTURE ADVECTION COULD
SPUR ON BATCH OF LGT SNOW ACROSS MAINLY NORTHERN CWA DURING THE DAY
ON THANKSGIVING. LIMITED MOISTURE WITH PWATS LESS THAN 100 PCT OF
NORMAL AND FOCUS OF STRONGER LIFT FM SHORTWAVE STAYING NORTH OF LK
SUPERIOR SHOULD LIMIT SNOW AMOUNTS. TROUGH SWINGING ACROSS NORTHERN
UPR MICHIGAN MAY KICK OFF SOME SNOW SHOWERS ACROSS KEWEENAW LATER
THURSDAY NIGHT INTO FRIDAY. CONSENSUS GIVES LOW CHANCE POPS BEYOND
FRIDAY WHICH IS FINE GIVEN DIFFERENCES IN TRACK OF SHORTWAVE/SFC
SYSTEM THAT GFS/ECMWF INDICATE MOVES THROUGH THE AREA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 658 AM EST SUN NOV 24 2013
AS HIGH PRES OVER NRN MO SHIFTS TO THE SE...EXPECT LOW LEVEL
WINDS TO BACK FROM THETHE W-NW EARLY THIS MORNING TO THE SW THIS
AFTERNOON. SINCE THIS FLOW DOWNSLOPES INTO SAW...VFR CONDITIONS
SHOULD PREDOMINATE. THE BEST CHC FOR MORE PERSISTENT MVFR CONDITIONS
WILL BE AT CMX AS THE NW TO W WIND WL UPSLOPE AFTER A LONGER
FETCH/MORE MOISTENING OVER LAKE SUPERIOR. BUT AS THE WIND SHIFTS TO
THE SW...VFR WX WILL TAKE OVER AT CMX EVEN THOUGH SOME FLURRIES/-SN
MAY FALL FROM A THICKENING MID CLOUD DECK RELATED TO THE RETURN OF
WARMER AIR. THE PRES GRADIENT OVER WRN UPPER MI WILL SHARPEN THIS
AFTERNOON AND EVENING...SO EXPECT A GUSTY WIND TO DEVEOP AT THE MORE
EXPOSED IWD AND SAW LOCATIONS. MVFR CONDITIONS MAY RETURN LATE
TONIGHT AS LOW LEVEL MOISTURE INCREASES AHEAD OF A TROUGH
APPROACHING THE AREA.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 440 AM EST SUN NOV 24 2013
NW WINDS TO 25 KTS DIMINISH THIS MORNING THEN SHIFT TO THE SW AND
INCREASE TO 30 KTS THIS EVENING. GALES EXPECTED OVR SUPERIOR ZONE
263 TONIGHT DUE TO CHANNELED FLOW BTWN KEWEENAW AND ISLE ROYALE.
WINDS TURN TO NORTHWEST ON MONDAY INTO TUESDAY AND REMAIN UP TO 30
KTS. FREEZING SPRAY MAY OCCUR LATER MONDAY INTO TUESDAY AS ANOTHER
PUSH OF COLDER AIR CROSSES LK SUPERIOR. GALE GUSTS POSSIBLE AS THE
COLDER AIR FIRST ARRIVES. EVENTUALLY WINDS BECOME NORTHERLY TUESDAY
NIGHT INTO WEDNESDAY THEN DIMINISH TO LESS THAN 20 KTS THROUGH THE
REST OF THE WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL NOON EST TODAY FOR MIZ006-007-
085.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THIS MORNING FOR
MIZ001>003.
LAKE SUPERIOR...
GALE WARNING FROM 5 PM THIS AFTERNOON TO 8 AM EST MONDAY FOR
LSZ263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...JLB
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
530 AM EST SUN NOV 24 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 526 AM EST SUN NOV 24 2013
WV IMAGERY AND RUC ANALYSIS INDICATED NW MID/UPPER LEVEL FLOW
THROUGH THE NRN GREAT LAKES WITH GRADUALLY RISING HEIGHTS AS THE
TROUGH OVER THE NE CONUS SLIDES TO THE EAST AND MID LEVEL RIDGING
BUILDS TOWARD THE AREA FROM SOUTH CENTRAL CANADA. AT THE SFC...A
RIDGE WAS BUILDING FROM NW WI AND WRN LAKE SUPERIOR INTO FAR W UPPER
MI WHILE LAKE INDUCED TROUGHING PREVAILED THROUGH ERN LAKE SUPERIOR.
SATELLITE AND RADAR INDICATED NW-SE ALIGNED WIND PARALLEL LES BANDS
HAD SHIFTED INTO LOCATIONS E OF MARQUETTE COUNTY. THE BANDS HAD
ALSO BECOME MORE CELLULAR WITH GRADUALLY DECREASING INTENSITY
OVERNIGHT. SFC OBS STILL INDICATED INTO W UPPER MI WITH CMX SHOWING
VSBY IN THE 1-3SM RANGE. HOWEVER...WEBCAMS FROM HOUGHTON AND CALUMET
SHOWED LITTLE SNOW OR VSBY REDUCTION.
THIS MORNING...
DESPITE 850 MB TEMPS AROUND -20C...INVERSION HEIGHTS DROPPING BELOW
5K FT AND VERY DRY AIR UPSTREAM WILL CONTINUE TO LIMIT LES
INTENSITY...ESPECIALLY OVER THE WEST. DIMINISHING WINDS WITH AN
INCREASED LAND BREEZE INFLUENCE AND A BACKING TREND WITH THE
APPROACHING RIDGE WILL RESULT IN A PERIOD OF ENHANCED CONVERGENCE
FROM ERN LAKE SUPERIOR INTO UPPER MI BETWEEN MUNISING AND NEWBERRY
WHERE ADDITIONAL SNOW AMOUNTS IN THE 1 TO 3 INCH RANGE ARE EXPECTED
THROUGH THE MORNING. THE BACKING WINDS SHOULD PUSH THE REMAINING LES
OFFSHORE IN THE AFTERNOON.
THIS AFTERNOON AND TONIGHT...
DEVELOPING WAA WITH STRONG 280K-295K PRES ADV BUT ONLY WEAK TO
MODERATE NET LIFT AHEAD OF A SHRTWV AND SFC LOW MOVING INTO CNTRL
MANITOBA MAY LEAD TO AN AREA OF LIGHT SNOW STREAKING SE INTO THE
NORTH AND EAST PORTIONS OF UPPER MI LATE THIS AFTERNOON AND EVENING.
HOWEVER...WITH THE DRY LOW LEVELS...LITTLE IF ANY SNOW ACCUMULATION
IS EXPECTED WITH ONLY SLIGHT CHANCE POPS INCLUDED. SNOW CHANCES WILL
INCREASE OVERNIGHT AS 700-300 MB QVECTOR CONV AHEAD OF THE SHORTWAVE
MOVES IN BUT SNOW AMOUNTS SHOULD REMAIN LESS THAN A HALF INCH. SW
FLOW LAKE ENHANCEMENT IS LIKELY TO DEVELOP OFF OF LAKE MICHIGAN BUT
THE LOW LEVEL WINDS VEER ENOUGH TO KEEP THE HIGHER SNOW
CHANCES/AMOUNTS TO THE SOUTH AND EAST OF SCHOOLCRAFT AND LUCE
COUNTIES.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 440 AM EST SUN NOV 24 2013
NORTHERN STREAM REMAINS ACTIVE THROUGH THE WEEK KEEPING THE COLD
ACROSS THE GREAT LAKES. NEXT CHARGE OF ARCTIC AIR ARRIVES LATER
MONDAY NIGHT INTO TUESDAY. LK EFFECT SNOW INCREASES MONDAY NIGHT
THROUGH TUESDAY NIGHT. AFTER HIGH PRESSURE RIDGE/SUBSIDENCE BRINGS
DIMINISHING TREND TO LK EFFECT LATER WEDNESDAY...ANOTHER SHORTWAVE
DROPPING THROUGH MAY BRING SOME LGT SNOW FOR THANKSGIVING DAY.
AGREEMENT FALLS OFF BY NEXT WEEKEND WITH THE ECMWF KEEPING A NW FLOW
ALOFT ACROSS GREAT LAKES AND BRINGING ANOTHER CLIPPER THROUGH ON
SATURDAY. GFS IS SLOWER AND MORE DEVELOPED BUT FARTHER NORTH WITH
NEXT TROUGH DROPPING THROUGH BY LATE IN THE WEEKEND.
MODELS IN OKAY AGREEMENT THROUGH 12Z TUESDAY THEN THEY BEGIN TO SHOW
DIFFERENCES. OVERALL THOUGH EVEN THE DISAGREEMENT...SPEED OF INITIAL
SHORTWAVE MOVING THROUGH UPR LAKES...DOES NOT HAVE HUGE IMPACTS ON
THE OVERALL THEME OF FORECAST. GFS ENDS UP BEING QUICKER THAN
ECMWF/NAM AND GEM-NH WITH HANDLING OF INITIAL SHORTWAVE. PLAN IS
THAT ON MONDAY MORNING SHORTWAVE WILL BE NORTH OF LK SUPERIOR WITH
TROUGH AXIS DROPPING ACROSS UPR LAKES. SFC LOW/H85 LOW AND SFC
TROUGH SWINGS ACROSS WESTERN UPR MICHIGAN BY MIDDAY AND INTO THE
EASTERN CWA BY EVENING. MAY SEE LGT LK EFFECT WITH MARGINAL TEMPS
AT INVERSION TOP MOST OF THE DAY OVER THE WEST...BETTER CHANCES WILL
BE LATER ON THOUGH. HINT THAT WEAK WAVE IN THE SOUTHERN STREAM
SLIDES WSW-ENE ACROSS MAINLY SOUTHERN SECTIONS OF WESTERN GREAT
LAKES AND INTERACTS WITH H8-H7 FRONTOGENESIS AND RIGHT ENTRANCE
REGION OF JET FM CNTRL GREAT LAKES TO SOUTHERN QUEBEC MONDAY MORNING
THROUGH MID MONDAY AFTN. SOME LGT SYNOPTIC SNOW MAY SCRAPE LK
MICHIGAN ZONES AND FAR EAST. IF THERE IS ENOUGH LOW-LEVEL MOISTURE
TO START THE DAY...COULD EVEN SEE A BIT OF FZDZ ALONG WI BORDER AS
DEEPER MOISTURE HEADS EAST. LAKE ENHANCEMENT EXPECTED OFF LK
MICHIGAN WITH SW FLOW AS H85 TEMPS ARE AROUND -8C. SHOULD STAY
EAST OF CWA THOUGH AS WINDS ARE FM SW INSTEAD OF SSW OR S. FARTHER
WEST...LK EFFECT SHOULD INCREASE LATER AFTN OVER WESTERN THIRD OF
CWA AS SYNOPTIC LIFT /-DIV-Q AT H7-H5/ FM APPROACHING SHORTWAVE
COMBINES WITH WNW WINDS THROUGH H85 AND TEMPS AT H85 OF -8C YIELDING
DELTA T/S UP TO 12C. INSTABILITY IS MARGINAL AND THUS EXPECT ONLY
MINOR SNOW ACCUMS THROUGH 00Z TUESDAY IN THE WEST.
MONDAY NIGHT INTO TUESDAY HOLDS GREATEST CHANCE FOR MODERATE TO
HEAVY LK EFFECT SNOW SHOWERS. OVERALL EXPECT MOST SNOW TO OCCUR FOR
AREAS FAVORED BY NNW WINDS THROUGH TUESDAY AND THEN SHIFT TO AREAS
FAVORED BY N OR NE WINDS ON TUESDAY NIGHT. UNLIKE THIS LAST EVENT
WHERE SNOWFALL AMOUNTS ENDED UP ON THE LOWER END OF FCST FOR MOST
AREAS...SHORTWAVE/ADDITIONAL SYNOPTIC MOISTURE IS FCST TO IMPACT UPR
LAKES DURING THE TIME OF THE LAKE EFFECT...ESPECIALLY THROUGH
TUESDAY. AT THE LEAST...EXPECT ADVY TYPE SNOWS WILL OCCUR FOR MAINLY
NNW-NW FLOW AREAS MONDAY NIGHT INTO TUESDAY. LACK OF PERSISTENT
UNIDIRECTIONAL FLOW IN LAKE EFFECT CONVECTIVE LAYER WILL LIMIT SNOW
AMOUNTS THOUGH THIS WILL PROBABLY BE OFFSET BY THE SHORTWAVE/DEEPER
MOISTURE. SEEMS LIKE HIGHER TERRAIN FROM IRONWOOD TO ROCKLAND TO
PAINESDALE AND ATLANTIC MINE WILL SEE THE MOST SNOW OVER THE WEST
WHILE FAVORED SNOWBELTS FROM EAST OF MARQUETTE TO NEWBERRY...
INCLUDING MOST OF ALGER COUNTY AND ALONG AND NORTH OF THE SENEY
STRETCH IN SCHOOLCRAFT COUNTY...WILL SEE THE MOST SNOW OVER THE CNTRL
AND EASTERN CWA. UNLIKE THIS LAST EVENT...WINDS SEEM MORE CERTAIN TO
VEER ENOUGH NORTHERLY TO ALLOW FOR LK EFFECT SNOWS TO IMPACT NCNTRL
UPR MICHIGAN /HIGHER TERRAIN OF BARAGA AND MARQUETTE COUNTIES/ LATER
TUESDAY INTO TUESDAY NIGHT AND PERHAPS LINGERING INTO MOST OF
WEDNESDAY. INVERSIONS LOWERING BLO 5KFT AND WINDS BECOMING VARIABLE
WILL DIMINISH SNOW OVER FAR WEST BY WEDNESDAY AFTN. A LIGHT BUT
PERSISTENT N-NE WIND MAY KEEP WEAKENING SNOW SHOWERS GOING THROUGH
MOST OF THE NIGHT BTWN MQT AND MUNISING. LIGHTER WINDS PROBABLY WILL
KEEP MOST OF SNOW SHOWERS RIGHT ALONG IMMEDIATE SHORE WITH SKIES
TRYING TO CLEAR OUT INLAND.
SHORTWAVE AND ARC OF WARM AIR ADVECTION/MOISTURE ADVECTION COULD
SPUR ON BATCH OF LGT SNOW ACROSS MAINLY NORTHERN CWA DURING THE DAY
ON THANKSGIVING. LIMITED MOISTURE WITH PWATS LESS THAN 100 PCT OF
NORMAL AND FOCUS OF STRONGER LIFT FM SHORTWAVE STAYING NORTH OF LK
SUPERIOR SHOULD LIMIT SNOW AMOUNTS. TROUGH SWINGING ACROSS NORTHERN
UPR MICHIGAN MAY KICK OFF SOME SNOW SHOWERS ACROSS KEWEENAW LATER
THURSDAY NIGHT INTO FRIDAY. CONSENSUS GIVES LOW CHANCE POPS BEYOND
FRIDAY WHICH IS FINE GIVEN DIFFERENCES IN TRACK OF SHORTWAVE/SFC
SYSTEM THAT GFS/ECMWF INDICATE MOVES THROUGH THE AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1239 AM EST SUN NOV 24 2013
AS HI PRES OVER IOWA SHIFTS STEADILY TO THE SE DURING THIS PERIOD...
EXPECT LLVL WINDS TO BACK FM THE W-NW EARLY THIS MRNG TO THE SW BY
THIS AFTN. ALTHOUGH SOME LINGERING LES MAY BRING MVFR CONDITIONS TO
IWD EARLY IN THE PERIOD UNDER LINGERING WNW FLOW...MINIMAL LK SUP
MOISTENING OF THE DRY ARCTIC AIRMASS WL ENSURE PREDOMINANT VFR
CONDITIONS FOR THAT LOCATION. SINCE THIS FLOW DOWNSLOPES INTO
SAW...VFR CONDITIONS SHOULD PREDOMINATE THERE AS WELL. THE BEST CHC
FOR MORE PERSISTENT MVFR TO PERHAPS IFR CONDITIONS WL BE AT CMX THRU
SUNRISE AS THE NW TO W WIND WL UPSLOPE AFT A LONGER FETCH/MORE
MOISTENING OVER LK SUP. BUT AS THE WIND SHIFTS TO THE SW ON SUN...
VFR WX WL THE RULE AT CMX AS WELL EVEN THOUGH SOME FLURRIES/-SN MAY
FALL FM A THICKENING MID CLD DECK RELATED TO THE RETURN OF WARMER
AIR. THE PRES GRADIENT OVER WRN UPR MI WL SHARPEN ON SUN AFTN/
EVNG...SO EXPECT A GUSTY WIND TO DVLP AT THE MORE EXPOSED IWD AND
SAW LOCATIONS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 440 AM EST SUN NOV 24 2013
NW WINDS TO 25 KTS DIMINISH THIS MORNING THEN SHIFT TO THE SW AND
INCREASE TO 30 KTS THIS EVENING. GALES EXPECTED OVR SUPERIOR ZONE
263 TONIGHT DUE TO CHANNELED FLOW BTWN KEWEENAW AND ISLE ROYALE.
WINDS TURN TO NORTHWEST ON MONDAY INTO TUESDAY AND REMAIN UP TO 30
KTS. FREEZING SPRAY MAY OCCUR LATER MONDAY INTO TUESDAY AS ANOTHER
PUSH OF COLDER AIR CROSSES LK SUPERIOR. GALE GUSTS POSSIBLE AS THE
COLDER AIR FIRST ARRIVES. EVENTUALLY WINDS BECOME NORTHERLY TUESDAY
NIGHT INTO WEDNESDAY THEN DIMINISH TO LESS THAN 20 KTS THROUGH THE
REST OF THE WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL NOON EST TODAY FOR MIZ006-007-
085.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THIS MORNING FOR
MIZ001>003.
LAKE SUPERIOR...
GALE WARNING FROM 5 PM THIS AFTERNOON TO 8 AM EST MONDAY FOR
LSZ263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...KC
MARINE...JLA
AREA FORECAST DISCUSSION
NWS DULUTH MN
903 AM CST SUN NOV 24 2013
.UPDATE...
ISSUED AT 902 AM CST SUN NOV 24 2013
MADE SOME ADJUSTMENTS TO REMOVE THE MENTION OF FLURRIES THIS
AFTERNOON. RH IN THE 1000MB-500MB RANGE IS LESS THAN 50 PERCENT
IN ALL AREAS EXCEPT WHERE THERE IS A MENTION OF ISOLD/SCT SNOW
SHOWERS NEAR THE INTERNATIONAL BORDER AND OVER THE ARROWHEAD. REST
OF THE FORECAST ON TRACK.
&&
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 400 AM CST SUN NOV 24 2013
A STRONG PUSH OF WARM AIR ADVECTION WILL OVERTAKE THE REGION TODAY
AS A LOW LEVEL TROUGH SWEEPS ACROSS THE DAKOTAS. LATEST MODELS IN
GOOD AGREEMENT THAT H85 TEMPS INCREASE ON THE ODER OF >10 C THROUGH
THE DAY AS A LOW LEVEL JET STREAK OF 40-50 KT WLY WINDS ADVECT
ACROSS CENTRAL MN. AFTERNOON TEMPERATURES WILL RETURN TO MORE
SEASONAL VALUES TODAY...IN THE MID TO UPPER 20S.
A FAST MOVING VORT MAX WILL SLIDE ALONG THE INTERNATIONAL BORDER
THIS MORNING...REACHING THE MN ARROWHEAD ZONES THIS AFTERNOON. THE
COMBINATION OF MID LEVEL OMEGA IN THE DENDRITIC GROWTH ZONE...AND
LAKE EFFECT/ENHANCEMENT FROM THE STRONG S/SW BOUNDARY LAYER WINDS
WILL PRODUCE A QUICK INCH OR SO ALONG THE NORTH SHORE OF LAKE
SUPERIOR TODAY. THE MAIN CORRIDOR OF SNOW ACCUMULATION WILL BE
ALONG HIGHWAY 61 FROM SILVER BAY...TO LUTSEN...GRAND MARAIS AND
GRAND PORTAGE. LOCATIONS IN THE ELEVATED TERRAIN OF COOK
COUNTY...A FEW MILES INLAND FROM LAKE SUPERIOR...CAN EXPECT
LOCALLY HIGHER AMOUNTS AROUND 2 INCHES DUE TO ENHANCED OROGRAPHIC
LIFT.
FOCUS TURNS TO THREAT FOR FREEZING DRIZZLE OVERNIGHT AHEAD OF
FRONTAL PASSAGE. LATEST NAM BUFR SOUNDINGS ACROSS MUCH THE
NORTHLAND SHOW PROFILES WITH A DEEP SATURATED LAYER...AND CLOUD
TOP TEMPERATURES IN THE SINGLE DIGITS BELOW ZERO LATE THIS EVENING
AS THE REGION REMAINS IN THE WARM SECTOR AHEAD OF THE TROUGH. THE
BEST FORCING OVERNIGHT...AND MAIN THREAT FOR FZDZ...WILL BE OVER
THE NRN WIS/EC MN AREAS WHERE H70-H85 OMEGA AND UPPER LVL JET
DIVERGENCE WILL BE GREATEST. THERE IS HIGHER UNCERTAINTY IN THE
PROBABILITY OF FZDZ OVER THE MN ZONES TONIGHT AS DRIER AIR RETURNS
ONCE THE TROUGH PASSES.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 400 AM CST SUN NOV 24 2013
THE UPPER PATTERN WILL START OUT WITH A RIDGE EXTENDING ALONG THE
WESTERN CONUS COAST INTO BC...WITH A TROUGH COVER MUCH OF THE
CENTRAL CONUS. THE NORTHLAND WILL BE IN NORTHWEST FLOW ALOFT. THE
PATTERN WILL CHANGE LATE IN THE PERIOD AS AN UPPER LOW SETTLES IN
JUST OFF THE SOUTHWEST CALIFORNIA COAST BY SATURDAY. OUR FLOW WILL
TURN MORE WNW. SEVERAL SHORTWAVES WILL BE MOVING THROUGH THE
NORTHWEST FLOW BRINGING A PERIOD OR TWO OF LIGHT SNOW/FLURRIES TO
THE NORTHLAND. A SIGNIFICANT LAKE EFFECT SNOW EVENT WILL BE POSSIBLE
TUESDAY INTO WEDNESDAY ALONG PORTIONS OF THE SOUTH SHORE.
TIMING DIFFERENCES AMONG THE MODELS SHOW UP EARLY IN THE
PERIOD...WITH THE GFS A BIT FASTER WITH A SHORTWAVE MONDAY NIGHT AND
TUESDAY AS WELL BEING FASTER PUSHING AN AREA OF HIGH PRESSURE
THROUGH THE AREA TUESDAY NIGHT/WEDNESDAY. WE FOLLOWED CLOSER TO A
BLEND OF THE ECMWF/NAM/GEM ON TIMING THESE FEATURES WHICH WERE ALL
SLOWER THAN THE GFS. SNOW SHOWERS WILL BE POSSIBLE MONDAY NIGHT AS
THE SHORTWAVE MOVES THROUGH AND ANOTHER SHOT OF COLDER AIR PUSHES
THROUGH. SNOW ACCUMULATIONS WILL BE LIGHT...WITH SOME AREAS PERHAPS
GETTING AROUND AN INCH...MAINLY FAR NORTH. LOW LEVEL WINDS LOOK TOO
WEST OF NORTH MONDAY NIGHT FOR LAKE EFFECT SNOW DESPITE THE COLD
AIR...-15C TO -17C OVER LAKE SUPERIOR AT 850MB.
EMPHASIS WILL SHIFT TO LAKE EFFECT SNOW ALONG THE SNOWBELT REGION OF
ASHLAND/IRON COUNTIES TUESDAY INTO WEDNESDAY AS LITTLE SNOW WILL
FALL OUTSIDE OF THIS AREA. WINDS VEER TO NORTHERLY TUESDAY WITH
850MB TEMPS AROUND -18C TO -20C. A LONG FETCH/LOW
STABILITY/INVERSION HEIGHTS WILL BE QUITE FAVORABLE FOR LES.
MOISTURE DEPTH ALSO LOOKS BETTER WITH THIS EVENT VERSUS THE RECENT
LES FRIDAY NIGHT/SATURDAY. THE LOW LEVEL WINDS ARE FORECAST TO VEER
TO MORE NORTHEAST TUESDAY NIGHT AND CONTINUE TO BE NNE ON WEDNESDAY.
THIS SHOULD SHIFT THE SNOW BANDS FURTHER WEST MORE INTO NORTHWEST
IRON INTO ASHLAND COUNTIES. CONDITIONS WILL GRADUALLY BECOME LESS
FAVORABLE FOR LES LATE TUESDAY NIGHT INTO WEDNESDAY AS BOTH THE
NAM AND ECMWF SHOW DRIER AIR MOVING OVER LAKE SUPERIOR ALONG WITH A
RIDGE OF HIGH PRESSURE. THE FETCH WILL BE MORE FAVORABLE THOUGH WITH
LONGER RESIDENCE TIME OVER THE LAKE. THE TUESDAY-WEDNESDAY MORNING
PERIOD BEARS A CLOSE WATCH AS A HEADLINE FOR SIGNIFICANT SNOW WILL
LIKELY BE NEEDED IF THESE FORECAST CONDITIONS CONTINUE.
A SHORTWAVE WEDNESDAY NIGHT/THURSDAY MAY BRING SOME LIGHT SNOW TO
NORTHERN PORTIONS OF THE REGION...WITH A BRIEF PERIOD OF LAKE
ENHANCED SNOW POSSIBLE ALONG COASTAL COOK COUNTY. ANOTHER SYSTEM
LATE IN THE PERIOD WILL BRING A CHANCE FOR SNOW...BUT SIGNIFICANT
SNOWFALL LOOKS UNLIKELY AT THIS POINT OUTSIDE OF THE LES CHANCES
MENTIONED ABOVE.
EXPECT HIGH TEMPERATURES TUESDAY TO BE IN THE TEENS TO AROUND 20
WITH THEM ONLY MODERATING SLIGHTLY THROUGH THE PERIOD TO 25
TO 30 BY NEXT SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 540 AM CST SUN NOV 24 2013
STRONG WAA OVER THE NORTHLAND WILL CAUSE MID-HIGH LEVEL CLOUDS TO
MOVE THROUGH THE AREA TODAY...WITH A CHANCE FOR LIGHT SNOW AND LOWER
CEILINGS ACROSS NORTHERN MINNESOTA. A COLD FRONT WILL THEN MOVE
INTO THE AREA TONIGHT. SOUNDINGS SUGGEST IF SOME PRECIPITATION
DOES OCCUR TONIGHT...FREEZING DRIZZLE WILL BE POSSIBLE. AT THIS
TIME...CONFIDENCE IN PRECIP COVERAGE IS LOW AND WE MENTION SOME
LIGHT SNOW THIS MORNING AT KINL...AND SOME FZDZ AT KHIB/KDLH/KHYR
LATER TONIGHT. KHYR HAS THE BEST CHANCE AT SEEING THE FZDZ. CEILINGS
TONIGHT WILL ALSO BE A QUESTION MARK...WITH THE RAP/NAM SHOWING
LOWER CEILINGS MOVING IN OR DEVELOPING. THE RAP HAS SLOWED THE
MOVEMENT OF LOWER CEILINGS ACROSS THE FAR NORTH WITH IT`S MOST
RECENT UPDATE. WE FEEL MOST CONFIDENT KINL AND KHYR WILL HAVE MVFR
CEILINGS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 26 20 31 11 / 10 20 10 20
INL 26 20 25 8 / 20 20 30 40
BRD 27 24 31 12 / 0 10 10 20
HYR 24 20 33 16 / 10 20 20 20
ASX 27 23 34 17 / 10 20 20 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY FROM NOON TODAY TO 10 AM CST WEDNESDAY FOR
LSZ121-146>148.
SMALL CRAFT ADVISORY FROM NOON TODAY TO 4 PM CST MONDAY FOR
LSZ140>145.
&&
$$
UPDATE...GSF
SHORT TERM...GRANING
LONG TERM...MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS DULUTH MN
547 AM CST SUN NOV 24 2013
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 400 AM CST SUN NOV 24 2013
A STRONG PUSH OF WARM AIR ADVECTION WILL OVERTAKE THE REGION TODAY
AS A LOW LEVEL TROUGH SWEEPS ACROSS THE DAKOTAS. LATEST MODELS IN
GOOD AGREEMENT THAT H85 TEMPS INCREASE ON THE ODER OF >10 C THROUGH
THE DAY AS A LOW LEVEL JET STREAK OF 40-50 KT WRLY WINDS ADVECT
ACROSS CENTRAL MN. AFTERNOON TEMPERATURES WILL RETURN TO MORE
SEASONAL VALUES TODAY...IN THE MID TO UPPER 20S.
A FAST MOVING VORT MAX WILL SLIDE ALONG THE INTERNATIONAL BORDER
THIS MORNING...REACHING THE MN ARROWHEAD ZONES THIS AFTERNOON. THE
COMBINATION OF MID LEVEL OMEGA IN THE DENDRITIC GROWTH ZONE...AND
LAKE EFFECT/ENHANCEMENT FROM THE STRONG S/SW BOUNDARY LAYER WINDS
WILL PRODUCE A QUICK INCH OR SO ALONG THE NORTH SHORE OF LAKE
SUPERIOR TODAY. THE MAIN CORRIDOR OF SNOW ACCUMULATION WILL BE
ALONG HIGHWAY 61 FROM SILVER BAY...TO LUTSEN...GRAND MARAIS AND
GRAND PORTAGE. LOCATIONS IN THE ELEVATED TERRAIN OF COOK
COUNTY...A FEW MILES INLAND FROM LAKE SUPERIOR...CAN EXPECT
LOCALLY HIGHER AMOUNTS AROUND 2 INCHES DUE TO ENHANCED OROGRAPHIC
LIFT.
FOCUS TURNS TO THREAT FOR FREEZING DRIZZLE OVERNIGHT AHEAD OF
FRONTAL PASSAGE. LATEST NAM BUFR SOUNDINGS ACROSS MUCH THE
NORTHLAND SHOW PROFILES WITH A DEEP SATURATED LAYER...AND CLOUD
TOP TEMPERATURES IN THE SINGLE DIGITS BELOW ZERO LATE THIS EVENING
AS THE REGION REMAINS IN THE WARM SECTOR AHEAD OF THE TROUGH. THE
BEST FORCING OVERNIGHT...AND MAIN THREAT FOR FZDZ...WILL BE OVER
THE NRN WIS/EC MN AREAS WHERE H70-H85 OMEGA AND UPPER LVL JET
DIVERGENCE WILL BE GREATEST. THERE IS HIGHER UNCERTAINTY IN THE
PROBABILITY OF FZDZ OVER THE MN ZONES TONIGHT AS DRIER AIR RETURNS
ONCE THE TROUGH PASSES.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 400 AM CST SUN NOV 24 2013
THE UPPER PATTERN WILL START OUT WITH A RIDGE EXTENDING ALONG THE
WESTERN CONUS COAST INTO BC...WITH A TROUGH COVER MUCH OF THE
CENTRAL CONUS. THE NORTHLAND WILL BE IN NORTHWEST FLOW ALOFT. THE
PATTERN WILL CHANGE LATE IN THE PERIOD AS AN UPPER LOW SETTLES IN
JUST OFF THE SOUTHWEST CALIFORNIA COAST BY SATURDAY. OUR FLOW WILL
TURN MORE WNW. SEVERAL SHORTWAVES WILL BE MOVING THROUGH THE
NORTHWEST FLOW BRINGING A PERIOD OR TWO OF LIGHT SNOW/FLURRIES TO
THE NORTHLAND. A SIGNIFICANT LAKE EFFECT SNOW EVENT WILL BE POSSIBLE
TUESDAY INTO WEDNESDAY ALONG PORTIONS OF THE SOUTH SHORE.
TIMING DIFFERENCES AMONG THE MODELS SHOW UP EARLY IN THE
PERIOD...WITH THE GFS A BIT FASTER WITH A SHORTWAVE MONDAY NIGHT AND
TUESDAY AS WELL BEING FASTER PUSHING AN AREA OF HIGH PRESSURE
THROUGH THE AREA TUESDAY NIGHT/WEDNESDAY. WE FOLLOWED CLOSER TO A
BLEND OF THE ECMWF/NAM/GEM ON TIMING THESE FEATURES WHICH WERE ALL
SLOWER THAN THE GFS. SNOW SHOWERS WILL BE POSSIBLE MONDAY NIGHT AS
THE SHORTWAVE MOVES THROUGH AND ANOTHER SHOT OF COLDER AIR PUSHES
THROUGH. SNOW ACCUMULATIONS WILL BE LIGHT...WITH SOME AREAS PERHAPS
GETTING AROUND AN INCH...MAINLY FAR NORTH. LOW LEVEL WINDS LOOK TOO
WEST OF NORTH MONDAY NIGHT FOR LAKE EFFECT SNOW DESPITE THE COLD
AIR...-15C TO -17C OVER LAKE SUPERIOR AT 850MB.
EMPHASIS WILL SHIFT TO LAKE EFFECT SNOW ALONG THE SNOWBELT REGION OF
ASHLAND/IRON COUNTIES TUESDAY INTO WEDNESDAY AS LITTLE SNOW WILL
FALL OUTSIDE OF THIS AREA. WINDS VEER TO NORTHERLY TUESDAY WITH
850MB TEMPS AROUND -18C TO -20C. A LONG FETCH/LOW
STABILITY/INVERSION HEIGHTS WILL BE QUITE FAVORABLE FOR LES.
MOISTURE DEPTH ALSO LOOKS BETTER WITH THIS EVENT VERSUS THE RECENT
LES FRIDAY NIGHT/SATURDAY. THE LOW LEVEL WINDS ARE FORECAST TO VEER
TO MORE NORTHEAST TUESDAY NIGHT AND CONTINUE TO BE NNE ON WEDNESDAY.
THIS SHOULD SHIFT THE SNOWBANDS FURTHER WEST MORE INTO NORTHWEST
IRON INTO ASHLAND COUNTIES. CONDITIONS WILL GRADUALLY BECOME LESS
FAVORABLE FOR LES LATE TUESDAY NIGHT INTO WEDNESDAY AS BOTH THE
NAM AND ECMWF SHOW DRIER AIR MOVING OVER LAKE SUPERIOR ALONG WITH A
RIDGE OF HIGH PRESSURE. THE FETCH WILL BE MORE FAVORABLE THOUGH WITH
LONGER RESIDENCE TIME OVER THE LAKE. THE TUESDAY-WEDNESDAY MORNING
PERIOD BEARS A CLOSE WATCH AS A HEADLINE FOR SIGNIFICANT SNOW WILL
LIKELY BE NEEDED IF THESE FORECAST CONDITIONS CONTINUE.
A SHORTWAVE WEDNESDAY NIGHT/THURSDAY MAY BRING SOME LIGHT SNOW TO
NORTHERN PORTIONS OF THE REGION...WITH A BRIEF PERIOD OF LAKE
ENHANCED SNOW POSSIBLE ALONG COASTAL COOK COUNTY. ANOTHER SYSTEM
LATE IN THE PERIOD WILL BRING A CHANCE FOR SNOW...BUT SIGNIFICANT
SNOWFALL LOOKS UNLIKELY AT THIS POINT OUTSIDE OF THE LES CHANCES
MENTIONED ABOVE.
EXPECT HIGH TEMPERATURES TUESDAY TO BE IN THE TEENS TO AROUND 20
WITH THEM ONLY MODERATING SLIGHTLY THROUGH THE PERIOD TO 25
TO 30 BY NEXT SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 540 AM CST SUN NOV 24 2013
STRONG WAA OVER THE NORTHLAND WILL CAUSE MID-HIGH LEVEL CLOUDS TO
MOVE THROUGH THE AREA TODAY...WITH A CHANCE FOR LIGHT SNOW AND LOWER
CEILINGS ACROSS NORTHERN MINNESOTA. A COLD FRONT WILL THEN MOVE
INTO THE AREA TONIGHT. SOUNDINGS SUGGEST IF SOME PRECIPITATION
DOES OCCURN TONIGHT...FREEZING DRIZZLE WILL BE POSSIBLE. AT THIS
TIME...CONFIDENCE IN PRECIP COVERAGE IS LOW AND WE MENTION SOME
LIGHT SNOW THIS MORNING AT KINL...AND SOME FZDZ AT KHIB/KDLH/KHYR
LATER TONIGHT. KHYR HAS THE BEST CHANCE AT SEEING THE FZDZ. CEILINGS
TONIGHT WILL ALSO BE A QUESTION MARK...WITH THE RAP/NAM SHOWING
LOWER CEILINGS MOVING IN OR DEVELOPING. THE RAP HAS SLOWED THE
MOVEMENT OF LOWER CEILINGS ACROSS THE FAR NORTH WITH IT`S MOST
RECENT UPDATE. WE FEEL MOST CONFIDENT KINL AND KHYR WILL HAVE MVFR
CEILINGS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 26 20 31 11 / 10 20 10 20
INL 26 20 25 8 / 20 20 30 40
BRD 27 24 31 12 / 0 10 10 20
HYR 24 20 33 16 / 10 20 20 20
ASX 27 23 34 17 / 10 20 20 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY FROM NOON TODAY TO 10 AM CST WEDNESDAY FOR
LSZ121-146>148.
SMALL CRAFT ADVISORY FROM NOON TODAY TO 4 PM CST MONDAY FOR
LSZ140>145.
&&
$$
SHORT TERM...GRANING
LONG TERM...MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
524 AM CST SUN NOV 24 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 323 AM CST SUN NOV 24 2013
1045 MB ARCTIC HIGH PRESSURE CENTERED NEAR KANSAS CITY WILL MOVE
RAPIDLY EAST THROUGH THE MIDSOUTH TODAY AND BE LOCATED OVER NORTH
CAROLINA BY MONDAY MORNING.
THE MODELS INSIST STRATUS WILL FORM IN THE RETURN FLOW SETTING
ACROSS SWRN NEB. AT 08Z THE NEAREST STRATUS WAS OVER NW TEX...ABOUT
500 MILES SOUTH OF THE FORECAST POSITION OF THE MODEL CONSENSUS. NO
STRATUS IS EXPECTED TO DEVELOP AT THIS TIME BUT MID LEVEL CLOUDS
ACROSS ERN COLO/WRN KS ARE EXPECTED TO LIFT NORTH PART WAY THROUGH
THE FCST AREA AND THEN GET SHUNTED EAST WITH THE APPROACH OF A NRN
STREAM SHORTWAVE THIS EVENING. TEMPERATURES ARE EXPECTED TO RISE
INTO THE 30S TO AROUND 40. WARMER GUIDANCE WAS USED FOR THE FORECAST
OWING TO THE CONTAMINATION IN THE SKY COVER SHOWN BY MOST MODELS.
FOR TONIGHT A COLD FRONT WILL BE MOVING SOUTH THROUGH THE NRN HIGH
PLAINS. A THERMAL RIDGE WILL BE RUNNING OUT AHEAD OF THE COLD FRONT
WHICH WILL LIKELY PRODUCE THE COOLEST LOWS IN THE SOUTH BEFORE THE
WIND SHIFT DEVELOPS LATE TONIGHT. THUS LOWS IN THE TEENS ARE
EXPECTED SOUTH WITH 20S NORTH.
SOUTH AND SOUTHWEST WINDS TODAY INCREASE TO 15 TO 25 MPH. LOW
PRESSURE CURRENTLY ACROSS GREAT SLAVE LAKE WILL DIVE SOUTHEAST
TOWARD LAKE SUPERIOR TODAY AND TONIGHT. THE 500M AGL WINDS IN THE
NAM AND RAP MODELS INCREASE TO NEAR 30 MPH AT THE SFC EAST OF
HIGHWAY 183. THIS WOULD SUPPORT GUSTS TO 35 MPH BUT LIMITED VERTICAL
MIXING IN COOL RETURN FLOW SHOULD LIMIT SUSTAINED WIND SPEEDS TO 25
MPH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 323 AM CST SUN NOV 24 2013
A SLOW MOVING UPPER LEVEL LOW PRESSURE SYSTEM WILL MIGRATE FROM
ARIZONA TO WEST TEXAS BY MONDAY. MEANWHILE ANOTHER POTENT
SHORTWAVE TROUGH WILL DIVE SOUTHEAST THROUGH CENTRAL
CANADA...REACHING THE GREAT LAKES BY TUESDAY EVENING. THE
SOUTHERN PLAINS LOW AND GREAT LAKES TROUGH WILL EVENTUALLY
PHASE TO OUR EAST...AND BRING HEAVY PRECIPITATION ALONG THE EAST
COAST WEDNESDAY AND WEDNESDAY NIGHT. AS MENTIONED...THE MAJORITY
OF THE WEATHER WITH THESE SYSTEMS REMAINS TO OUR EAST...BUT A COLD
FRONT WILL DROP SOUTH THROUGH THE AREA TUESDAY. THIS WILL BRING
ANOTHER REINFORCING SHOT OF ARCTIC AIR TO THE REGION. THE BRUNT OF
THE ARCTIC AIR WILL BE FELT ACROSS THE MISSOURI RIVER
VALLEY...WHERE HIGHS IN THE 20S ARE EXPECTED. FARTHER WEST ACROSS
THE HIGH PLAINS OF WESTERN NEBRASKA AND EASTERN COLORADO...THE
COLD FRONT WILL HAVE LITTLE IMPACT...WITH A PACIFIC AIRMASS AND
HIGHS IN THE 40S REMAINING IN PLACE.
BY MID TO LATE WEEK...UPPER LEVEL RIDGING WILL BUILD EAST ACROSS
THE CENTRAL CONUS. WARMER PACIFIC AIR WILL ALSO SPREAD EAST...WITH
HIGHS IN THE UPPER 30S TO MID 40S REGION WIDE. LITTLE
PRECIPITATION IS EXPECTED...AS ATMOSPHERIC MOISTURE REMAINS
LIMITED THROUGH THE END OF THE WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 523 AM CST SUN NOV 24 2013
VFR IS EXPECTED ALL AREAS TODAY AND TONIGHT. MIDLEVEL CLOUD SHIELD
ACROSS NERN COLO/SWRN NEB/NWRN KS WILL MOVE NORTH TO NEAR KTIF AND
THEN GET SHUNTED EAST AS AN UPPER LEVEL DISTURBANCE...CURRENTLY
NEAR GREAT SLAVE LAKE...DROPS SOUTH INTO SRN CANADA. A COLD FRONT
WILL MOVE THROUGH THE FCST AREA TONIGHT PRODUCING A WIND SHIFT
WITH NW WINDS DEVELOPING.
NOTE THE MODELS DEVELOP LOW CLOUDS/MVFR CIGS THIS MORNING ACROSS
SRN NEB AND EXPAND THESE CLOUDS NORTH TONIGHT BUT THIS FCST HAS
NOT VERIFIED SINCE 00Z LAST NIGHT SO WE ARE SETTING THAT FCST
ASIDE AND WAITING ON SFC OBS TO SHOW THIS DEVELOPMENT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
254 AM PST SUN NOV 24 2013
.SYNOPSIS...A SLOW MOVING LOW PRESSURE WILL FINALLY PULL AWAY FROM
THE AREA TODAY RESULTING IN DRIER CONDITIONS. FURTHER WARMING IS
EXPECTED ACROSS THE AREA MONDAY THROUGH WEDNESDAY. ANOTHER AREA OF
LOW PRESSURE DROPPING SOUTH NEAR THE CALIFORNIA COAST MAY BRING A
FEW SHOWERS MAINLY TO WESTERN PORTIONS OF THE AREA FOR THANKSGIVING
DAY AND FRIDAY.
&&
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT.
WELL AFTER 3 DAYS OF CLOUDS AND RAIN WE ARE FINALLY IN FOR A CHANGE
TODAY IN VEGAS WITH THE POTENTIAL OF SEEING SOME SUNSHINE AS A SLOW
MOVING UPPER LEVEL LOW FINALLY HEADS OUT OF THE AREA. THE LATEST
WATER VAPOR IMAGERY SHOWS THE CENTER OF THE LOW NEAR PARKER, ARIZONA
AS OF EARLY THIS MORNING WITH MOISTURE STILL WRAPPING AROUND THE
BACK SIDE OF THE LOW. THE MAIN ISSUE FOR TODAY, ESPECIALLY FOR THIS
MORNING, WILL BE HOW QUICKLY WE ARE ABLE TO DRY THINGS OUT ACROSS
THE AREA WHICH WILL DETERMINE WHEN SHOWERS COME TO AN END AND HOW
QUICKLY ANY LOW AND MID-LEVEL CLOUDS START TO BECOME MORE SCATTERED.
THE LATEST RADAR IMAGES FROM KESX SHOW MAINLY LIGHT RETURNS ACROSS
THE EASTERN PORTIONS OF THE AREA AND IT IS LIKELY THE RADAR IS
OVERSHOOTING SOME OF THE PRECIPITATION. BASED ON THE HRRR AND THE
00Z REGIONAL WRF, THE BEST POTENTIAL FOR ANY SHOWERS THIS MORNING
WILL BE ACROSS NORTHERN AND CENTRAL MOHAVE COUNTY, LINCOLN COUNTY
AND THE MOUNTAINS OF CLARK COUNTY AND I HAVE KEPT IN 20-30 POPS WITH
SOME NEAR 40 POP VALUES (IN THE HIGHEST TERRAIN) OVER THESE AREAS.
AS THE LOW LEVELS START TO DRY OUT, WE SHOULD SEE THE LOWER AND
MID-LEVEL CLOUDS START TO BECOME MORE SCATTERED IN COVERAGE BY EARLY
THIS AFTERNOON ESPECIALLY FROM LINCOLN AND CLARK COUNTIES ON EAST.
THERE COULD BE A LITTLE FOG AROUND, MAINLY ALONG THE INTERFACES OF
THE HIGHER TERRAIN WHERE THEY HIT THE CLOUD BASES. OUTSIDE OF THE
COLORADO CITY AREA WHERE FOG WAS REPORTED EARLIER THIS MORNING, NO
OTHER FOG WILL BE PLACED IN THE GRIDS AS THE COVERAGE LOOKS TOO
SMALL. WITH THE COLD POOL DEPARTING THE AREA ASSOCIATED WITH THE
LOW, A LOT OF WARMING ALOFT WILL TAKE PLACE TODAY. THIS COMBINED
WITH SOME SUN WILL MAKE FOR A BIG BOOST IN TEMPS, HOWEVER, HIGHS
SHOULD STILL BE ABOUT 10 DEGREES BELOW NORMAL ACROSS THE AREA AND I
DID CHOP A FEW DEGREES OFF THE PREVIOUS FORECAST BASED ON THE LATEST
GUIDANCE.
FOR TONIGHT, SOME LOW AND MID-LEVEL CLOUDS MAY LINGER EARLY ON,
OTHERWISE EXPECT A CLEAR SKY. TEMPS SHOULD BE A LITTLE COLDER WITH
LESS CLOUD COVER. ONE CONCERN WILL BE IN THE WESTERN PORTIONS OF THE
MOJAVE DESERT, MAINLY ACROSS NW SAN BERNARDINO COUNTY AND FAR SW
INYO COUNTY, WHERE PATCHY FOG MAY BE POSSIBLE. STATISTICAL GUIDANCE
SHOWS NEARLY SATURATED OR SATURATED SFC CONDITIONS TONIGHT
(ESPECIALLY THE COLDER MET GUIDANCE) AND BUFKIT SOUNDINGS FROM THE
NAM SHOW THE VERY LOW-LEVELS MOISTENING AROUND OR JUST AFTER
SUNRISE. I WILL GO AHEAD AND ADD PATCHY FOG IN HERE GIVEN THE WET
GROUND FROM THE RECENT RAINS, LIGHT WINDS AND CLEAR SKY EXPECTED
INITIALLY TONIGHT, HOWEVER CONFIDENCE IS NOT THE BEST WITH THIS.
RIDGING ALOFT IS FORECAST TO SLIDE EAST ACROSS THE AREA FROM MONDAY
INTO TUESDAY. THIS WILL RESULT IN FURTHER WARMING WITH HIGHS ABOUT
4-6 DEGREES BELOW NORMAL. AS THE RIDGE AXIS SLIDES EAST ON TUESDAY
AND A TROUGH OFFSHORE STARTS TO APPROACH HIGH LEVEL MOISTURE SHOULD
START TO SPILL IN FROM THE WEST AND COULD BRING A DECENT AMOUNT OF
CIRRUS TO THE AREA FOR TUESDAY NIGHT.
.LONG TERM...WEDNESDAY THROUGH SATURDAY...THE PACIFIC SYSTEM THAT IS
FORECAST TO APPROACH THE WEST COAST BY LATE WEDNESDAY DOES NOT
APPEAR TO HAVE THE MAKINGS OF A SIGNIFICANT STORM FOR OUR FORECAST
AREA. THE LATEST MEDIUM RANGE MODELS ARE NOW IN BETTER AGREEMENT
WITH THE TRACK OF THE SYSTEM....BRINGING THE CENTER OF THE CLOSED
LOW ALONG THE CENTRAL CALIFORNIA COAST THANKSGIVING DAY THEN
INDICATING IT WILL TRANSFORM INTO A WEAKER AND ELONGATED POSITIVE
TILT TROUGH AS IT SAGS OFF THE SOUTHERN CALIFORNIA COAST FRIDAY AND
CONTINUES WORKING TOWARD NORTHERN BAJA SATURDAY. THE BEST CHANCE FOR
PRECIPITATION WILL BE ACROSS THE SOUTHERN SIERRA AND THE INYO COUNTY
MOUNTAINS THANKSGIVING DAY INTO THURSDAY NIGHT AS A SHORTWAVE EJECTS
OUT OF THE COASTAL LOW ACROSS SOUTHEAST CALIFORNIA AND SOUTHERN
NEVADA. SNOW WILL BE LIKELY IN THE HIGH SIERRA WITH LESSER CHANCES
FOR LIGHT SNOW SHOWERS ACROSS THE REST OF THE INYO COUNTY MOUNTAINS
AND THE MOUNTAINS OF SOUTHERN NEVADA. PRECIPITATION CHANCES THEN
DIMINISH CONSIDERABLY FRIDAY INTO SATURDAY. CONSIDERING THE SEED FOR
THIS SYSTEM IS CURRENTLY A BARELY NOTICEABLE PACIFIC SHORTWAVE NEAR
40N AND THE DATELINE...THERE ARE SURE TO BE SOME CHANGES DURING ITS
EVOLUTION. IT BEARS WATCHING BUT DOES NOT LOOK THAT IMPRESSIVE FOR
NOW.
&&
.AVIATION...FOR MCCARRAN...THE MAIN ISSUE THIS MORNING WILL BE WITH
CIGS. CIGS INITIALLY SHOULD BE AROUND 4K FEET OR SO...BUT SOME
DRYING OF THE LOWER LEVELS OF THE ATMOSPHERE TAKES PLACE...LOWER
CLOUD BASES SHOULD BECOME MORE IN THE SCT-BKN RANGE WITH CLOUDS
BASES MAINLY AOA 5-8K FEET. CLOUDS SHOULD BE EXTENSIVE ALONG THE
EDGES OF THE VALLEY WITH MOUNTAIN OBSCURATIONS LIKELY THROUGH 18Z OR
SO TODAY. BY 00Z CLOUDS SHOULD BECOME MORE FEW-SCT AOA 5-8K FEET
WITH A CLEAR SKY EXPECTED TONIGHT. WINDS SHOULD FAVOR TYPICAL
DIURNAL TRENDS THROUGH TONIGHT AT SPEEDS OF 5 KTS OR LESS.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...SHOWERS SHOULD DECREASE IN COVERAGE THIS MORNING AND BE
DONE ACROSS ALL AREAS EXCEPT EASTERN MOHAVE COUNTY BY 18Z TODAY AND
ANY LINGERING SHOWERS THERE SHOULD END BY 21Z TODAY OR SO. SCT-BKN
CLOUDS AOA 5K-8K FEET OTHERWISE TODAY WITH VFR VSBY EXCEPT NEAR ANY
FOG THIS MORNING. WINDS OVERALL SHOULD BE 10 KTS OR LESS WITH SPEEDS
TRENDING TOWARDS TYPICAL DIURNAL COMPONENTS OR A NORTHERLY
DIRECTION. FOR TONIGHT A CLEAR SKY IS EXPECTED WITH WINDS FAVORING
DIURNAL TRENDS. PATCHY FG/BR POSSIBLE IN AND AROUND KDAG AND
ELSEWHERE IN NW SAN BERNARDINO COUNTY WITH VSBY POTENTIALLY DROPPING
TO AT LEAST MVFR.
&&
.CLIMATE...WE HAVE HAD OUR FILL OF CLOUDS IN THE SKY HERE IN VEGAS
THE LAST FEW DAYS BUT WHEN IS THE LAST TIME WE HAD 3 DAYS WITH THIS
MUCH CLOUD COVER AROUND? BASED ON SUNRISE TO SUNSET CLOUD COVER, THE
LAST TIME WE HAD BACK-TO-BACK DAYS WITH A 10 (WHICH MEANS AS CLOUDY
AS IT GETS) WAS ON DECEMBER 20TH AND 21ST OF 2010. THOSE AROUND THEN
HERE WILL REMEMBER THAT AS A PERIOD WHEN A BARRAGE OF STORMS CAME IN
FROM THE PACIFIC. THIS WAS ALSO THE ONLY SUCH PERIOD LOOKING BACK
THROUGH SKY COVER RECORDS FOR THE LAST 5 YEARS TO NOVEMBER 2008.
&&
.VEF WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
AZ...NONE.
CA...NONE.
&&
$$
SHORT TERM/AVIATION/CLIMATE...STACHELSKI
LONG TERM...ADAIR
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
931 AM EST SUN NOV 24 2013
.SYNOPSIS...
THE NORTH COUNTRY WILL REMAIN UNDER COLD NORTHWESTERLY FLOW FOR
TODAY AND TONIGHT...AS LOW PRESSURE REMAINS TO OUR EAST AND HIGH
PRESSURE OFF TO OUR WEST. THAT AREA OF HIGH PRESSURE WILL SHIFT
EAST OVER THE REGION LATER TONIGHT...FOLLOWED BY ANOTHER LOW FOR
MONDAY AFTERNOON INTO TUESDAY. THERE IS THE POTENTIAL FOR A WINTER
STORM TO AFFECT THE REGION STARTING LATE TUESDAY NIGHT AND INTO
WEDNESDAY NIGHT. HIGH PRESSURE SLOWLY RETURNS FOR THURSDAY INTO
FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 931 AM EST SUNDAY...HAVE UPDATED THE FORECAST TO RAISE POPS
ACROSS MUCH OF NC/NE VT THROUGH THE DAY...AND TO INTRODUCE AREAS
OF BLOWING SNOW IN THESE AREAS. ALSO LOWERED HOURLY AND MAX
TEMPERATURES BY A FEW DEGREES BASED OFF CURRENT OBSERVATIONAL DATA
AND LATEST LAMP GUIDANCE NUMBERS. COLD DAY ON TAP WITH STRONG AND
GUSTY NORTHWESTERLY FLOW CONTINUING. THUS WIND ADVISORIES REMAIN
IN PLACE...ESP ACROSS THE HIGHER TERRAIN AND DOWNSLOPE LOCATIONS
ALONG THE EASTERN SLOPES OF THE DACKS/GREENS. STRONGEST GUSTS
LIKELY THIS AFTERNOON WHEN SECONDARY PRESSURE SURGE PUSHES SOUTH
INTO THE REGION. GUSTS IN ADVISORY LOCATIONS IN THE 35 TO 45 MPH
RANGE WITH LOCALLY HIGHER GUSTS...SLIGHTLY LESS ELSEWHERE. WHILE
MOISTURE CONTINUES TO SLOWLY THIN...LINGERING WRAP- AROUND
OROGRAPHICALLY ENHANCED SHSN CONTINUE ACROSS THE NRN MTNS WHERE
SOME MINOR ADDITIONAL ACCUMULATIONS WILL BE POSSIBLE TODAY. THIS
IS IN CLOSE AGREEMENT WITH LATEST 12/13Z RAP PROGS WHICH HAVE A
GOOD HANDLE ON THE CURRENT SITUATION. THUS WILL LEAN IN ITS
DIRECTION ACCORDINGLY. WITH DEEPLY MIXED PBL...FROUDE NUMBERS
QUITE HIGH SO BEST COVERAGE OF SHSN/ACCUMS FROM THE GREEN MTN
SPINE EASTWARD. TEMPERATURES REALLY GOING NOWHERE WITH SUCH STRONG
CAA IN PLACE...SO READINGS HOLDING MORE OR LESS STEADY...PERHAPS
CLIMBING A DEGREE OR TWO WILL BE ALL WE GET TODAY. WITH THE
AFORMENTIONED WINDS THE APPARENT TEMPS SHOULD RANGE IN THE -10F TO
+5F RANGE...COLDER TO NEAR -20F AT THE SUMMITS. DEFINITELY A DAY
TO WEAR THE FULL WINTER CLOTHING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
AS OF 352 AM EST SUNDAY...TONIGHT WITH RIDGE APPROACHING AND WINDS
ABATING...TEMPS WILL DROP SHARPLY TO LOWEST OF THE SEASON SO FAR
WITH LOWS RANGING FROM -5 TO 10F IN DACKS TO SINGLE NUMBERS
ELSEWHERE. WIND ADVISORY REMAINS IN AFFECT THRU TNGT AS TIGHT
GRADIENT CREATING STEADY 15-30 MPH WINDS WITH GUSTS
40-50MPH...HIGHEST OVER DACKS AND E VT. BY 00Z MONDAY...GRADIENT
WILL SLACKEN AND TAPER OFF BY MIDNGT WITH ARRIVAL OF SFC RIDGE.
WIND CHILL ISSUES POSSIBLE IN RANGE OF 0F TO -10F.
COLD CHILLY MORNING ON MONDAY W/ RIDGE CRESTING OVER THE AREA AND
SLIDING S AND E DURING THE DAY. THIS WILL ALLOW WAA ON SSW FLOW TO
SETUP OVER THE AREA...AND PROVIDE A NICE REBOUND IN TEMPS FROM THE
COLD WEEKEND. WAA WILL BRING HIGHS MONDAY INTO THE 20S FOR ALL
SITES. INCR CLDS THOUGH OVER N NY AS NORTHERN STREAM SYSTEM COMES
OUT OF THE GREAT LKS REGION AND INTO QUEBEC MON AFTNOON/TUESDAY
MORNING. BLOCKING RIDGE TO OUR SOUTH WILL PUT BEST POP FOCUS OVER
N NY TAPERING DOWN TO SE VT. ADDITIONAL LIGHT SNOWFALL WILL OCCUR
BRINGING AROUND AN INCH OF NEW SNOW TAPERING OFF TO A POTENTIAL
DUSTING IN SOUTHERN ZONES. CLD COVER KEEPS TEMPS FROM DROPPING TOO
MUCH ALONG WITH GRADIENT STAYING SW. LOOKING FOR LOWS IN THE TEENS
TO L20S. GOING INTO TUESDAY SW GRADIENT STAYS INTACT FOR THE DAY
AS NORTHERN SYSTEM...THAT COULD BRING STORM NEAR
THANKSGIVING...SWINGS THRU THE GREAT LKS. CLDS/MOISTURE FEED WILL
ALLOW FOR SL CHANCE OF -SW WITH FOCUS OVER SOUTHERN ZONES. OVERALL
INCH OR LESS EXPECTED...WITH HIGHS IN THE 30S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 640 AM EST SUNDAY...STILL CONSIDERABLE MODEL DIFFERENCES
CONCERNING MOISTURE-LADEN SYNOPTIC LOW EXPECTED TO AFFECT THE
NORTH COUNTRY TUESDAY NIGHT INTO WEDNESDAY...WHICH UNFORTUNATELY
COINCIDES WITH ONE OF THE BUSIEST TRAVEL DAYS OF THE YEAR. THE 00Z
NWP DIFFERENCES CONTINUE TO SURROUND INTERACTION BETWEEN VIGOROUS
BUT DISTINCT NRN AND SRN STREAM SHORTWAVE TROUGHS AS SYSTEMS CROSS
THE OHIO VALLEY AND SERN STATES...RESPECTIVELY. THE DEEPER AND
MORE PHASED SOLN OFFERED BY THE 00Z ECMWF TAKES THE LOW INLAND UP
THE EAST COAST AND ULTIMATELY TRACKS A 986MB LOW ACROSS VT BETWEEN
18Z WED AND 00Z THU. THIS IS A WARMER SOLN WITH 850MB TEMPS
REACHING +8C ACROSS VT AT 18Z WEDNESDAY. ANY SNOW AT THE ONSET TUESDAY
NIGHT WOULD SWITCH OVER TO MAINLY RAIN ACROSS THE REGION.
MEANWHILE...THE 00Z GFS CONTINUES THAT MODEL/S TENDENCY TO KEEP A
FASTER MOVING SYSTEM OFFSHORE BETWEEN THE 40N 70W BENCHMARK AND
CAPE COD WITH A 994MB LOW MOVING THROUGH AT 18Z WEDNESDAY. THIS IS
A MUCH COLDER SOLN...WITH POTENTIAL ACCUMULATING SNOW ACROSS VT
AND LESS PRECIPITATION IMPACT FOR NRN NY. HAVE INCREASED POPS TO
70-80 PERCENT LATE TUESDAY THROUGH WEDNESDAY ASSOCIATED WITH THIS
SYSTEM WITH QPF ON THE ORDER OF 1"...BUT IT REMAINS TOO SOON TO
DETERMINE P-TYPE DETAILS GIVEN UNCERTAIN EVOLUTION/PHASING OF NRN
AND SRN STREAMS. THOSE WITH TRAVEL PLANS WEDNESDAY SHOULD CONSIDER
PROSPECT FOR WINTER TRAVEL CONDITIONS ACROSS THE NORTH
COUNTRY...BUT THAT IS BY NO MEANS A SURE THING AT THIS POINT.
WE/LL MAINTAIN MENTION OF THIS SYSTEM IN THE HAZARDOUS WEATHER
OUTLOOK.
CONDITIONS WILL TREND COLDER AND DRIER FOR THANKSGIVING DAY AS
SYNOPTIC LOW DEPARTS NEWD THRU QUEBEC/CANADIAN MARITIMES. NWLY
WINDS AT 10-20 MPH WITH A FEW FLURRIES IN THE NRN GREENS INTO NERN
VT. LOWS WEDNESDAY NIGHT WILL BE IN THE UPR TEENS TO LOWER
20S...FOLLOWED BY HIGHS MAINLY IN THE 20S FOR THANKSGIVING DAY.
HIGH PRESSURE SHOULD BRING DRY AND SEASONABLY COLD CONDITIONS
FRIDAY AND SATURDAY. HIGH TEMPS GENERALLY REMAIN IN THE 20S THRU
THE END OF THE FORECAST PERIOD SATURDAY.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
THROUGH 12Z MONDAY...ARCTIC FRONT HAS PUSHED EAST OF THE REGION AND
STRONG W-NW WINDS WILL CONTINUE IN ITS WAKE AT ALL TAF SITES TODAY
AND INTO THIS EVENING. SNOW SHOWER ACTIVITY IS GRADUALLY
DECREASING WITH DRIER AIR MOVING IN...BUT PERIODS OF IFR SNOW MAY
CONTINUE AT MPV/SLK THRU 16Z. AT BTV...NW WINDS 15-20KTS WITH
GUSTS TO 28KTS ARE EXPECTED THROUGH 15Z...INCREASING TO 20G34KT
DURING THE AFTN HOURS. CEILINGS MAINLY MVFR AREAWIDE...IMPROVING
TO VFR LATE TODAY WITH CLEARING AND DIMINISHING WINDS TONIGHT.
OUTLOOK 06Z MONDAY THROUGH THURSDAY...DRY AND MOSTLY CLEAR VFR
WITH HIGH PRESSURE IN PLACE MONDAY. THERE WILL BE A CHANCE FOR
MVFR CIGS/VIS IN SNOW SHOWERS MONDAY NIGHT AND TUESDAY AS WEAK
UPPER LEVEL TROUGH MOVES ACROSS THE NORTH COUNTRY. LOW
PREDICTABILITY FOR WEDNESDAY WITH UNCERTAIN TRACK OF COASTAL LOW
PASSING SE-E OF CAPE COD. POSSIBILITY EXISTS FOR IFR CONDITIONS
AND ACCUMULATING SNOWFALL WEDNESDAY BUT DETAILS ARE UNCERTAIN.
THURSDAY...MODERATE N-NW WINDS WITH ISOLD -SHSN POSSIBLE...MAINLY
VCNTY MTNS. TAF LOCATIONS SHOULD BE MAINLY VFR FOR THURSDAY.
&&
.MARINE...
AS OF 352 AM EST SUNDAY...A LAKE WIND ADVISORY REMAINS IN EFFECT
AND WILL LIKELY REMAIN SO THROUGH TONIGHT. WINDS NORTHWEST 20 TO
30 KNOTS...TAPERING TO 15 TO 25 KNOTS TONIGHT. WAVES WILL BUILD TO
3-5 FEET IMPACTING NORTH-FACING EXPOSURES.
&&
.CLIMATE...
THE COLD TEMPERATURES SUNDAY 11/24 INTO MONDAY 11/25 MAY APPROACH
RECORD LEVELS. THE RECORDS ARE LISTED BELOW:
RECORD LOW AND RECORD LOW MAXIMUMS SUNDAY 11/24:
BURLINGTON (BTV)- 2 (1956), 19 (1938)
MONTPELIER (MPV)- -4 (1989), 20 (2000)
MASSENA (MSS)- -8 (2000), 19 (1996)
SAINT JOHNSBURY (SJBV1)- -6 (1989), 20 (1921)
RECORD LOW AND RECORD LOW MAXIMUMS MONDAY 11/25:
BURLINGTON (BTV)- -1 (1938), 14 (1938)
MONTPELIER (MPV)- 4 (1997,1993), 24 (1993,1971)
MASSENA (MSS)- 5 (2005), 23 (1993)
SAINT JOHNSBURY (SJBV1)- 0 (1956), 19 (1938)
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR VTZ003-004-
006>008-010-012-016>019.
NY...WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR NYZ028-031-034-
035.
&&
$$
SYNOPSIS...JN
NEAR TERM...JMG
SHORT TERM...JN
LONG TERM...BANACOS
AVIATION...BANACOS
MARINE...LOCONTO
CLIMATE...MUCCILLI
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
642 AM CST SUN NOV 24 2013
.UPDATE...
ISSUED AT 642 AM CST SUN NOV 24 2013
NO MAJOR CHANGES THIS MORNING. THE RAP AND HRRR CONTINUE TO TRY
AND BRING SOME PRECIP IN FROM THE NORTHWEST BY THIS AFTERNOON.
HOWEVER...ACTUAL SOUNDINGS AT KBIS AND KINL SHOW VERY DRY AIR
BELOW 700MB WHICH FITS WITH THE NAM AND GFS MODELS. THE RAP ALSO
SEEMS TO BE OVERDOING PRECIP CURRENTLY OVER CANADA COMPARING MODEL
OUTPUT TO SFC OBS. AND EVEN THE RAP HAS THE SHOWERS WEAKENING AS
THEY MOVE INTO THE CWA. THINK THAT WE WILL SEE SOME INCREASED
CLOUD COVER AND SOME VIRGA WITH THE FRONTAL BOUNDARY...BUT NOTHING
REACHING THE GROUND. MADE A FEW MINOR TWEAKS TO TEMPS BUT NO MAJOR
CHANGES.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 303 AM CST SUN NOV 24 2013
PRECIP CHANCES AND TEMPERATURES WILL BE THE MAIN FORECAST
CHALLENGE THROUGH THE PERIOD.
SFC TROUGH DEVELOPING OVER SASK HAS ALLOWED WINDS TO SHIFT BACK TO
THE SOUTH AND BECOMING QUITE BREEZY. THE WINDS HAVE HELPED TEMPS
CLIMB BACK INTO THE POSITIVE DIGITS...AND SHOULD HELP TEMPS CLIMB
INTO THE UPPER 20S TO LOW 30S THIS AFTERNOON. HOWEVER...AN
APPROACHING SHORTWAVE CAN BE SEEN ON WV LOOP COMING TOWARDS THE
REGION. CANADIAN RADAR SHOWS SOME ACTIVITY OVER CENTRAL
MANITOBA...AND MODELS HAVE SOME OF THIS PRECIP CLIPPING THE LAKE
OF THE WOODS AREA NEAR 12Z. IT IS UNCERTAIN HOW MUCH IS REACHING
THE GROUND AT THIS POINT...BUT WILL KEEP SOME LOW POPS GOING THIS
MORNING FOR OUR FAR NORTHEAST.
THE MAIN SHORTWAVE WILL DIG FURTHER SOUTH INTO MANITOBA
TODAY...AND INTO ONTARIO TONIGHT. THE UPPER SYSTEM SHOULD HELP
PUSH THE SFC TROUGH EASTWARD...WITH ANOTHER COLD FRONT MOVING INTO
THE REGION THIS EVENING. A FEW OF THE SHORT RANGE MODELS HAVE SOME
PRECIP DEVELOPING AHEAD OF THE FRONT THIS AFTERNOON...MAINLY OVER
THE NORTHERN CWA. HOWEVER...THERE IS QUITE A BIT OF DRY AIR AT LOW
LEVELS...AND AT THIS POINT IT SEEMS LIKE NOTHING WILL REACH THE
GROUND. THE LARGER SCALE MODELS ALL KEEP US DRY. WILL LEAVE A
MENTION OUT FOR NOW BUT KEEP A CLOSE EYE...AS MODEL THERMAL
PROFILES SHOW THAT FZRA COULD BE POSSIBLE IF ANYTHING DOES REACH
THE GROUND.
ANOTHER...STRONGER SHORTWAVE WILL MOVE INTO SOUTHERN MANITOBA FOR
MONDAY. PLENTY OF COLD AIR WILL BE MOVING BACK IN BEHIND THE
DEPARTING SFC LOW...KEEPING TEMPS IN THE TEENS SUNDAY NIGHT AND
THE 20S INTO MONDAY. THE APPROACHING SHORTWAVE WILL BRING AN
INCREASING CHANCE FOR SNOW SHOWERS TO OUR NORTHEASTERN CWA DURING
THE DAY ON MONDAY.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 303 AM CST SUN NOV 24 2013
MONDAY NIGHT...THE SHORTWAVE OVER MANITOBA WILL DIG INTO THE GREAT
LAKES...BRINGING A CONTINUED CHANCE FOR SNOW OVER LAKE OF THE
WOODS AND DRAGGING ANOTHER SURGE OF COLD AIR BEHIND IT. THE AIR
MASS WILL BE QUITE COLD ALTHOUGH WITH CLOUDS AT NIGHT THINK WE
WILL NOT BE AS COLD AS SATURDAY MORNING. KEPT LOWS IN THE SINGLE
DIGITS AND HIGHS IN THE TEENS.
WEDNESDAY THROUGH SATURDAY NIGHT..NORTHWEST FLOW ALOFT CONTINUES
WITH CANADIAN SHORT-WAVE PASSING THROUGH THE NORTHERN PLAINS
WEDNESDAY AND FRIDAY NIGHT INTO SATURDAY. THE FIRST OF THESE IS
EXPECTED TO BE DRY WITH THE BEST MOISTURE/LIFT NORTH OF THE
INTERNATIONAL BORDER. THE SECOND MAY BRING A LOW CHANCE FOR LIGHT
SNOW FRIDAY NIGHT INTO SATURDAY...ALTHOUGH THERE ARE SOME MAJOR
DIFFERENCES BETWEEN THE 00 UTC GFS/ECMWF IN FRONTAL ORIENTATION/
LOCATION/TIMING. WILL FOLLOW ALL BLEND 20 POPS FOR NOW. WEDNESDAY
WILL BE THE COOLEST DAY OF THE PERIOD WITH A GRADUAL WARMING TREND
INTO THE WEEKEND. EVEN SO...DAILY HIGHS LIKELY TO REMAIN BELOW
FREEZING AND MAINLY IN THE 20S. OVERNIGHT LOWS WILL DROP INTO THE
TEENS EACH MORNING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 642 AM CST SUN NOV 24 2013
CONDITIONS WILL REMAIN VFR WITH INCREASING HIGH AND MID LEVEL
CLOUDS TODAY. CIGS SHOULD BE AT 10000 AT THE LOWEST DURING THE
AFTERNOON AS A COLD FRONT MOVES IN. SOUTH WINDS TODAY WILL BE
QUITE BREEZY AHEAD OF THE FRONT WITH GUSTS ABOVE 20 KTS BUT WILL
SHIFT TO THE WEST BY AFTERNOON AND THE NORTHWEST TONIGHT.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...JR
LONG TERM...JR/ROGERS
AVIATION...JR
AREA FORECAST DISCUSSION
NWS PUEBLO CO
242 PM MST SUN NOV 24 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 241 PM MST SUN NOV 24 2013
...SNOW WINDING DOWN ON MONDAY...
UPPER LOW IS NOW NOW MOVING EASTWARD ALONG THE CO NM BORDER. COLDER CLOUD
TOPS HAVE SHIFTED TO THE NE PORTION OF CO...WHERE SEVERAL BANDS OF
SNOW ARE ROTATING NORTHWESTWARD ALONG THE NRN I-25 CORRIDOR. THE LOW HAS
DEFINITELY TAKEN A MORE NRN TRACK AS THE NAM AND ESPECIALLY THE
ECMWF HAD FORECAST IT TO DO. HOWEVER...NOT A LOT OF MOISTURE LEFT
WITH THE SYSTEM...AND ACCUMS TONIGHT INTO MON MORNING PROBABLY WILL
NOT BE ALL THAT IMPRESSIVE. MAIN FOCUS FOR HEAVIER ACCUMS WILL BE
DUE TO N-NE WINDS INCREASING TONIGHT AS THE LOW CONTINUES TO MOVE
AWAY. LATEST RUC SHOWING H7 WINDS INCREASING TO 30-40 KTS AFTER
ABOUT 04Z TONIGHT. THIS WILL LEAD TO SOME DECENT OROGRAPHIC ACCUMS
OVER THE HIGHER ELEVATIONS OF THE ERN MT RANGES OVERNIGHT...AND
FAVORED SPOTS LIKE CUCHARA COULD SEE SOME RESPECTABLE SNOWFALL.
LATEST HI RES MODELS REALLY SHOWING THIS POTENTIAL OVER THE WETS AND
NRN SANGRES...SO WILL ADD THE WETS TO THE CURRENT SUITE OF
ADVISORIES WE HAVE OUT THROUGH 12Z MONDAY. ELSEWHERE...BEST BET OF
SNOW OVER THE PLAINS WILL BE ALONG AND WEST OF I-25...AND ESPECIALLY
SOUTH OF HIGHWAY 50. COULD SEE SOME LIGHT ACCUMS OVER THE HIGHER
TRRN BUT NOT EXPECTING ANYTHING SIGNIFICANT. INHERITED LOW POPS FOR
THE PLAINS STILL LOOK ON TARGET SO HAVE NOT MADE ANY EXTENSIVE
CHANGES THERE.
SHOULD SEE SNOW TAPER OFF FROM N TO S ESPECIALLY AFTER MID-MORNING
ON MONDAY. JUST A FEW LINGERING SHOWERS OVER THE SRN MTS AND FAR
SERN PLAINS BY MON AFTERNOON. BREEZY CONDITIONS WILL PERSIST IN THE
WAKE OF THE LOW...ESPECIALLY OVER BACA COUNTY WHICH COULD SEE SOME
GUSTS IN THE 30-40 KT RANGE FOR THE LATE MORNING TO EARLY AFTERNOON
PERIOD. TEMPS ALOFT WILL ACTUALLY BE FALLING SIGNIFICANTLY THROUGH
MONDAY MORNING...DOWN TO AROUND MINUS 7 OR 8 C AT H7...BUT WITH GOOD
MIXING IN THE LOW TO MID LEVELS...SHOULD SEE TEMPS TOP OUT HIGHER
THAN THE TEMPS THIS AFTERNOON. HAVE CUT BACK TEMPS A BIT BELOW
GUIDANCE HOWEVER...SINCE EVEN WITH GOOD ADIABATIC MIXING THE TEMPS
ALOFT WILL PROBABLY ONLY SUPPORT 40 DEGREES OR SO AT BEST BY THE
AFTERNOON. SO...IT WILL BE A RAW DAY DESPITE THE LOWERED POPS.
ROSE
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 241 PM MST SUN NOV 24 2013
MONDAY NIGHT...UPPER LOW OVER WEST TEXAS FORECAST BY MODELS TO SLIDE
SOUTHEAST...BUT SOME MOISTURE IN NORTHERLY FLOW ALOFT WILL PERSIST
THROUGH PART OF THE NIGHT. INHERITED ISOLATED POPS AT MOST OVER THE
EASTERN MOUNTAINS THROUGH MIDNIGHT...AND THAT LOOKS GOOD. SNOW
ACCUMULATIONS WILL BE WELL UNDER AN INCH. LOW TEMPERATURES WILL BE
IN THE LOWER SINGLE DIGITS ACROSS THE SAN LUIS VALLEY...WITH SNOW
COVER AND RADIATIONAL COOLING. ELSEWHERE...TEMPERATURES SHOULD DIP
INTO THE TEENS ACROSS THE PLAINS AND OTHER HIGH VALLEYS...WITH
SINGLE DIGITS ACROSS THE HIGHEST ELEVATIONS.
FOR THE REMAINDER OF THE WEEK AND INTO NEXT WEEKEND...THE WEATHER
LOOKS TO BE FAIRLY TRANQUIL...AS AN UPPER LEVEL RIDGE GETS
ESTABLISHED OVER THE GREAT BASIN AND ROCKIES. A WEAK FRONT MAY
BRIEFLY AFFECT THE EASTERN PLAIN THANKSGIVING DAY...BUT WITH NO
PRECIPITATION. A COUPLE MORE SHORTWAVES IN THE NORTHERN
STREAM...WILL BRING SOME CLOUDS...WITH THE SECOND ONE...DURING THE
WEEKEND...BRINGING A CHANCE FOR SOME HIGHER ELEVATION SNOW SHOWERS.
-TLM-
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY AFTERNOON)
ISSUED AT 241 PM MST SUN NOV 24 2013
SNOW SHOWERS LINGERING OVER NRN EL PASO COUNTY SHOULD CONTINUE TO
MOVE OFF TO THE NW LATE THIS AFTERNOON. NO SIGNIFICANT ACCUMULATIONS
ARE EXPECTED WITH THIS ACTIVITY. KCOS COULD SEE ANOTHER ROUND OF
INTERMITTENT LIGHT SN LATER THIS EVE...BUT IT SHOULD NOT LAST LONG
AND SHOULD NOT LINGER MUCH BEYOND 12Z MON. KPUB WILL SEE CHANCES OF
SNOW LINGER A BIT LONGER INTO MON MORNING...BUT NOT EXPECTING MUCH
IN THE WAY OF ACCUMULATIONS THERE EITHER. IT CURRENTLY LOOKS LIKE
MOST OF THE HEAVIER SNOWFALL OVERNIGHT WILL STAY SOUTH OF HIGHWAY 50.
KALS WILL SEE A GOOD CHANCE OF LIGHT SNOW THROUGH THIS EVE AND
OVERNIGHT...WITH LIGHT ACCUMS OF A COUPLE INCHES POSSIBLE BY EARLY
MONDAY. SHOULD SEE CONDITIONS IMPROVE FROM NW TO SE THROUGH
MONDAY...WITH JUST SOME LINGERING SHOWERS OVER THE HYR TRRN. MAIN
STORY TOMORROW WILL BE THE INCREASED N-NE WINDS...WHICH WILL REMAIN
GUSTY OVER THE PLAINS THROUGH THE EARLY AFTERNOON BEFORE QUIETING
DOWN LATER IN THE DAY. ROSE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 AM MST MONDAY FOR COZ060-066-
073>075-080.
WINTER STORM WARNING UNTIL 5 AM MST MONDAY FOR COZ068.
&&
$$
SHORT TERM...ROSE
LONG TERM...TM
AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS ALBANY NY
345 PM EST SUN NOV 24 2013
.SYNOPSIS...
THE CENTER OF THIS ARCTIC AIRMASS WILL MOVE ACROSS THE REGION TONIGHT.
WHILE SOME LAKE EFFECT CLOUDS AND SNOW SHOWERS ARE
POSSIBLE...THE SURFACE HIGH WILL BUILD INTO THE REGION FOR SKIES
TO BECOME MAINLY CLEAR OVERNIGHT. WINDS WILL SUBSIDE AND
TEMPERATURES WILL FALL TO THE LOWEST LEVELS THIS SEASON THUS FAR.
AS THIS HIGH MOVES OFFSHORE...WE TURN OUR ATTENTION TO A
DEVELOPING COASTAL STORM THAT WILL IMPACT THE REGION HEADING INTO
THE THANKSGIVING HOLIDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
THE CENTER OF THIS ARCTIC AIRMASS WILL SETTLE ACROSS THE REGION
TONIGHT. THOSE H850 TEMPS PER THE RUC13 BOTTOM OUT NEAR -20C THIS
EVENING. THIS WILL KEEP LAKE EFFECT ACTIVITY GOING FOR MOST OF THE
NIGHT...HOWEVER...INVERSION LEVELS WILL DROP AS THAT SURFACE AND
LOW LEVEL RIDGE AXIS CREST OVER THE REGION. LOW LEVEL WINDS
CURRENTLY AROUND 330-350 DEGREES ARE EXPECTED TO BACK TOWARD
310-330 DURING TONIGHT THEN GRADUALLY TOWARD 270 DEGREES TOWARD
SUNRISE. WE WILL RETAIN SLIGHT CHANCE TO CHANCE POPS FOR SNOW
SHOWERS FOR PORTIONS OF THE CATSKILLS...SCHOHARIE VALLEY AND
EVENTUALLY INTO THE MOHAWK VALLEY AND ADIRONDACKS THROUGH THE
OVERNIGHT.
CLOUDS TOO WILL BE PROBLEMATIC AND MOST OF THE REGION SHOULD
BECOME MOSTLY CLEAR OVERNIGHT. LAKE CLOUDS WILL HANG ON CLOSER TO
THE LAKES WHERE THE AFOREMENTIONED AREAS WHERE LAKE EFFECT SNOW
SHOWERS ARE EXPECTED. TEMPERATURES WILL DROP BACK AT OR BELOW
ZERO FOR THE ADIRONDACKS TO SINGLE DIGITS AND AROUND 10 DEGREES
ELSEWHERE.
AS FOR THE WINDS...WE WILL RETAIN THE ADVISORY THROUGH THE EVENING
HOURS BUT EXPECTATIONS ARE FOR THE BOUNDARY LAYER TO DECOUPLE AND/OR
FOR THE RIDGE TO BUILD IN TO ALLOW THE WIND GUSTS TO SUBSIDE BELOW
ADVISORY LEVEL.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
...POTENT COASTAL STORM IS EXPECTED TO IMPACT THE REGION TUESDAY
INTO THURSDAY...
MOST OF THE ATTENTION ON THIS FORECAST HAS BEEN ON THE DEVELOPING
COASTAL STORM SET TO IMPACT HOLIDAY TRAVEL LEADING INTO
THANKSGIVING. LATEST TRENDS IN THE NCEP MODEL SUITE ALONG WITH
INTERNATIONAL GLOBAL MODELS ARE TRENDING A LITTLE FURTHER WEST
/THE GFS IS QUICKLY TRENDING IN THIS DIRECTION ALONG WITH THE MOST
OF THE ENSEMBLE MEMBERS/. THIS WOULD SUGGEST THAT THE BULK OF THE
PRECIPITATION WILL FALL IN THE FORM OF RAIN FROM THE HUDSON RIVER
VALLEY AND POINTS SOUTH AND EAST THROUGH THE HEART OF THE EVENT.
HOWEVER...WITH A FAIRLY TIGHT BAROCLINIC ZONE AND ANY SLIGHT
DEVIATION TO THIS TRACK WILL HAVE SIGNIFICANT IMPACTS TO PRECIP
TYPE ACROSS THE REGION. PER THE LOW LEVEL U/V COMPONENT FROM THE
GEFS...AT THIS TIME THE WARM AIR SHOULD ERODE THE COLDER AIR FOR
THE EASTERN 2/3RD OF THE CWFA AS WE WILL TREND IN THIS DIRECTION
FOR THE FORECAST.
MONDAY...
SURFACE HIGH CRESTS OVER THE REGION WITH LAKE EFFECT ACTIVITY
IMPACTING PORTIONS OF THE DACKS IN THE MORNING AS THE LOW LEVEL
FLOW CONTINUES TO BACK THROUGH THE DAY. OTHERWISE...MOST OF THE
DAY SHOULD REMAIN DRY AS TEMPERATURES REBOUND INTO THE 20S AND
SOME LOWER 30S AS THE H850 TEMPS "WARM" INTO THE NEGATIVE SINGLE
DIGITS TO AROUND -10C DURING THE AFTERNOON. WITHIN THIS WARM
ADVECTION...SOME INCREASE IN HIGH AND MID LEVEL CLOUD COVER IS
ANTICIPATED.
MONDAY NIGHT...
A RATHER FAST MOVING CLIPPER TYPE SYSTEM TRACKING IN-BETWEEN THE
GREAT LAKES REGION AND JAMES BAY WILL BRING A COLD FRONT ACROSS
THE REGION. THIS MAY TOUCH OFF SOME SNOW SHOWERS...ESPECIALLY
DOWNWIND OF LAKE ONTARIO...WITH ACCUMULATIONS 1-2 INCHES IN
PERSISTENT SNOW SHOWERS WILL GENERALLY ONE INCH OR LESS FOR THE
CWFA.
TUESDAY INTO WEDNESDAY...
AS SEEN IN THE H2O VAPOR LOOP...CUT OFF UPPER LOW OVER THE FOUR
CORNERS REGION AND A COUPLE OF STRONG PV IMPULSES APPROACHING LAKE
WINNIPEG ARE EXPECTED TO CARVE OUT A RATHER SIGNIFICANT TROUGH
OVER THE EASTERN THIRD OF THE CONUS DURING THIS TIME STEP OF THE
FORECAST. THESE WAVES ARE EXPECTED TO PHASE WITH CYCLOGENESIS
EVOLVING OVER THE SOUTHEAST-MID ATLANTIC REGION DURING WEDNESDAY.
A PRONOUNCED AGEOSTROPHIC RESPONSE WILL DEVELOP AS THE LOW LEVEL
WARM ADVECTION RAPIDLY INCREASES UP THE EASTERN SEABOARD. PWAT
ANOMALIES OF 1-3 STANDARD DEVIATIONS ABOVE NORMAL ARE EXPECTED FOR
MOST OF THE REGION WITH THE LOW LEVEL JET APPROACHING 4 STANDARD
DEVIATIONS ABOVE NORMAL. THE NAM IS THE OUTLIER WITH ITS
EXCEPTIONALLY HIGH QPF WITH THE GLOBAL MODELS MUCH MORE TAME AND
IN CLOSE AGREEMENT WITH 1-2 INCHES OF RAIN/WATER-EQUIVALENT FOR
THE EVENT. PRECIPITATION FROM THIS EVOLVING SYSTEM IS EXPECTED TO
DEVELOP SOUTH TO NORTH DURING TUESDAY AND OVERSPREAD THE REGION
TUESDAY NIGHT. AT THIS TIME...WITH A SLIGHTLY FURTHER WEST
SOLUTION...WE UTILIZED A BLENDED PARTIAL THICKNESS SCHEME FROM THE
GLOBAL MODELS WHICH SUGGESTS A LITTLE LIGHT SNOW INITIALLY THEN
QUICKLY CHANGING OVER TO A MIX LATE TUESDAY THEN CONTINUING TO
WARM TUESDAY NIGHT FROM AT LEAST THE HUDSON RIVER VALLEY AND
POINTS SOUTH AND EAST. TO THE WEST OF THIS LINE...A POTENTIALLY
PROLONGED PERIOD OF WINTRY MIX IS EXPECTED AS THIS MAY PROVE TO TO
BE VERY CHALLENGING ASPECT TO THIS FORECAST. IN COLLABORATION WITH
WPC-WWD...A SIGNIFICANT AMOUNT OF SNOW/SLEET/FREEZING RAIN IS
POSSIBLE FOR PORTIONS OF THE DACKS...WESTERN MOHAWK VALLEY AND
PERHAPS INTO THE SCHOHARIE VALLEY. WE WILL CONTINUE TO HIGHLIGHT
IN THE HWO.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
WEDNESDAY NIGHT THROUGH THURSDAY...THE 12Z MODELS AND GUIDANCE
CONTINUE TO SHOW A COASTAL STORM MOVE UP THE ATLANTIC COASTLINE.
THERE IS STILL A LARGE DISAGREEMENT IN TERMS WHAT THE
PRECIPITATION TYPE AND THE AMOUNT OF QPF THAT WILL ACCUMULATE
BETWEEN THE FORECAST MODELS. AS WE GO INTO LATE WEDNESDAY
NIGHT...SOME NEW 12Z MODEL DATA SHOWS A SECONDARY SURFACE LOW
PRESSURE SYSTEM DEVELOPING ACROSS CENTRAL NEW ENGLAND WITHIN A
FAVORABLE SYNOPTIC UPPER LEVEL DIVERGENCE REGION EMBEDDED IN A
STRONG VERTICALLY ORIENTED UPPER LEVEL JET...ACCOMPANIED BY A
DEVELOPING NEGATIVE TILTED UPPER LEVEL TROUGH MOVING EAST FROM
LAKE ERIE OVER CENTRAL PENNSYLVANIA. IF THIS MODEL RUN WERE TO
VERIFY...COLD NORTH TO NORTHWESTERLY FLOW ON THE BACKSIDE OF THE
DEPARTING LOW PRESSURE SYSTEM WILL ANCHOR IN ENOUGH COLD AIR FOR
THIS SYSTEM TO END AS SNOW AS THE MAIN LOW PRESSURE FEATURE MOVES
NORTHEAST OVER NEW BRUNSWICK. THE POSSIBILITY OF A COUPLE INCHES
OF SNOW...ESPECIALLY FROM THE SARATOGA REGION POINTS NORTH AND
WEST IS POSSIBLE AS T850 AND T925 WILL BE WELL BELOW 0C ACROSS THE
REGION AS WE GO PAST 00Z THURSDAY. ONE GENERAL CONSENSUS AS OF NOW
BETWEEN THE MODELS IS THAT THE BEST BAROCLINICITY AND Q-VECTOR
FORCING APPEARS TO BE JUST OFF THE SOUTHERN COAST OF LONG ISLAND
WHERE THE MOST CONCENTRATED QPF AMOUNTS WILL BE AS THE MAIN AREA
OF LOW PRESSURE MOVING NORTHEAST UP THE COASTLINE ALONG AN UPPER
LEVEL WAVE OF LOW PRESSURE. THEREFORE...FOR THE START OF THE LONG
TERM SECTION...VARIATIONS TO THE BAROCLINIC POSITION WITH
THICKNESSES WELL ABOVE 540 DAM AT 500 HPA AHEAD OF A SECONDARY
UPPER LEVEL LOW PRESSURE WAVE MOVING EAST FROM THE GREAT LAKES MAY
DELAY THE CHANGEOVER FROM RAIN TO WINTRY MIX AND SNOW UNTIL MID
THURSDAY MORNING. AT THIS TIME HOWEVER...THERE ARE STILL MANY
VARIATIONS IN PRECIPITATION TYPES AND EVEN TEMPERATURE OUTLOOKS
DURING THE EVENT SO FURTHER UPDATES WILL BE NEEDED AS WE GET
CLOSER TO THE EVENT.
THURSDAY NIGHT THROUGH SUNDAY...AS THE MAIN LOW PRESSURE SYSTEM
EXITS THE ATLANTIC COASTLINE WELL INTO CANADA...LARGE AREA OF
SUBSIDENCE WILL MOVE INTO THE REGION GIVING TRANQUIL WEATHER
CONDITIONS. WITH A NORTHWESTERLY FLOW MODERATING TO A MORE WESTERLY
FLOW BY SUNDAY...TEMPERATURES WILL STILL REMAIN BELOW NORMAL WITH
TEMPERATURES RANGING FROM THE MID 20S TO LOWER 30S FOR FRIDAY AND
SATURDAY WITH TEMPERATURES MODERATING FROM THE UPPER 20S TO MID 30S
BY SUNDAY ACROSS THE ENTIRE REGION.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE 24 HOUR PERIOD
ENDING 18Z MONDAY...WITH A COLD AND DRY NORTHWEST FLOW ACROSS THE
AREA AS HIGH PRESSURE BUILDS IN FROM THE WEST.
THE MAIN AVIATION CONCERN CONTINUES TO BE STRONG NORTHWEST WINDS
THIS AFTERNOON INTO THIS EVENING. SUSTAINED WINDS OF GENERALLY 17
TO 22 KT ARE EXPECTED...WITH GUSTS TO AROUND 30 TO 40 KTS. THE
STRONGEST WINDS WILL OCCUR AT KALB AND KPSF. AFTER SUNSET WINDS
SPEEDS WILL SLOWLY SUBSIDE...BUT GUSTS OF 15 TO 20 KTS WILL
CONTINUE UNTIL LATE EVENING OR MIDNIGHT. WINDS WILL DECREASE
FURTHER SHORTLY BEFORE SUNRISE MONDAY.
OUTLOOK...
MONDAY THROUGH MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: LOW OPERATIONAL IMPACT. CHANCE OF RA.
TUESDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA...SN...IP.
WEDNESDAY: MODERATE OPERATIONAL IMPACT. LIKELY RA.
WEDNESDAY NIGHT: MODERATE OPERATIONAL IMPACT. LIKELY SHRA...SHSN.
THANKSGIVING DAY: LOW OPERATIONAL IMPACT. BREEZY. NO SIG WX.
&&
.HYDROLOGY...
NO HYDROLOGY PROBLEMS THROUGH EARLY THIS WEEK AS ICE WILL BE
BUILDING DUE TO SUB FREEZING TEMPERATURES INTO EARLY NEXT WEEK.
THEREAFTER...A POTENT COASTAL STORM WILL IMPACT THE REGION WITH
MODERATE TO POTENTIALLY SIGNIFICANT AMOUNTS OF WATER EQUIVALENT.
THE TIME FRAME WILL BE FROM TUESDAY AFTERNOON INTO WEDNESDAY
EVENING AS A COASTAL STORM COULD BRING 1.5 TO 2.5 INCHES OF LIQUID
EQUIVALENT PRECIPITATION TO THE REGION /LOCALLY HIGHER IS
POSSIBLE/. IT WILL BEGIN AS SNOW AND COULD LINGER AS SNOW IN THE
NORTHERN MOUNTAINS...HOWEVER IN MUCH OF THE REGION IT IS EXPECTED
TO CHANGE TO RAIN...RESULTING IN SIGNIFICANT WITHIN BANK RISES. IN
THIS STORMS WAKE IT WILL TURN SHARPLY COLDER AGAIN WEDNESDAY
NIGHT...WITH ICE FORMATION LIKELY TO BEGIN ANEW.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR CTZ001-013.
NY...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NYZ032-033-
038>043-047>054-058>061-063>066-082>084.
MA...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MAZ001-025.
VT...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR VTZ013>015.
&&
$$
SYNOPSIS...BGM
NEAR TERM...BGM
SHORT TERM...BGM
LONG TERM...LFM
AVIATION...JPV
HYDROLOGY...BGM
FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT
WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1136 AM MST SUN NOV 24 2013
.UPDATE...
ISSUED AT 1132 AM MST SUN NOV 24 2013
AXIS OF STRONG WINDS HAS DEVELOPED A BIT FARTHER SOUTH THAN
PREVIOUSLY EXPECTED...WITH BREAK IN CLOUDS ALLOWING DEEPER MIXING
TO OCCUR AS FAR SOUTH AS TRB RESULTING IN WINDS QUICKLY
APPROACHING ADVISORY LEVELS AND HAVE EXPANDED ADVISORY TO THE
SOUTH IN RESPONSE.
UPDATE ISSUED AT 904 AM MST SUN NOV 24 2013
WIND GUSTS OF 38 KTS AT LAA AND 41 KTS AT ITR IN THE LAST HOUR
INDICATE BOUNDARY LAYER BEGINNING TO TAP INTO STRONG JET OF LOW
LEVEL WINDS AS PER LATEST RAP AND KGLD VWP. AM A LITTLE CONCERNED
ABOUT AREA OF 50KTS OVER EASTERN COLORADO AT 1 KM AGL...BUT THAT
IS EXPECTED TO WEAKEN OVER THE NEXT 2 HOURS SO DO NOT ANTICIPATE
THE NEED FOR A HIGH WIND WARNING. A WIND ADVISORY DOES APPEAR
NECESSARY AND HAVE ISSUED ONE BASICALLY FOLLOWING EXPECTED CORE OF
STRONGEST 1 KM AGL WINDS THE NEXT FEW HOURS...WITH WINDS EXPECTED
TO DIMINISH IN THE AFTERNOON. MAY SEE SNOW SHOWERS MAKE IT INTO
THIS AREA OF STRONG WINDS...BUT THINK INTENSITY AND DURATION DOES
NOT WARRANT ANY KIND OF PREDOMINANT BLOWING SNOW ADVISORY.
&&
.SHORT TERM...(TODAY AND TUESDAY NIGHT)
ISSUED AT 149 AM MST SUN NOV 24 2013
THE UPPER LEVEL LOW PRESSURE SYSTEM EXPECTED TO AFFECT THE
FORECAST AREA WILL MOVE SLOWLY ACROSS THE DESERT SOUTHWEST AND
SOUTHERN ROCKIES TODAY. AHEAD OF THIS SYSTEM...LIGHT SNOW WILL
SPREAD NORTHWARD OUT OF EASTERN NEW MEXICO AND THE PANHANDLE
REGION OF TEXAS AND OKLAHOMA INTO PORTIONS OF EASTERN COLORADO AND
WESTERN KANSAS. THE BEST CHANCE OF ACCUMULATING SNOWFALL WILL BE
THIS MORNING MAINLY ALONG AND SOUTH OF INTERSTATE 70 WHERE AN INCH
OR LESS OF TOTAL ACCUMULATION IS POSSIBLE.
THE UPPER LOW CENTER WILL PHASE INTO THE MAIN UPPER TROUGH THAT
DEEPENS OVER THE GREAT LAKES AND MISSISSIPPI VALLEY REGION
TONIGHT. THE LOW WILL THEN BEGIN TO MOVE SOUTHEASTWARD OVER TEXAS
WITH DRYER AIR ALOFT AND SUBSIDENCE MOVING OVER THE CENTRAL HIGH
PLAINS REGION TONIGHT. THE UPPER RIDGE AMPLIFYING OVER THE WESTERN
UNITED STATES MOVES OVER THE INTERMOUNTAIN REGION MONDAY NIGHT AND
TUESDAY AND BEGINS TO MOVE OVER THE ROCKIES ON TUESDAY NIGHT.
ALTHOUGH TEMPERATURES WILL BE GRADUALLY INCREASING THROUGH THE
FIRST PART OF THE WORK WEEK AS HIGH PRESSURE MOVES INTO THE
REGION...MODEL TRENDS HAVE BEEN CONSISTENTLY LOWERING TEMPERATURES
WITH EACH SUBSEQUENT MODEL RUN OVER THE PAST FEW DAYS. TEMPERATURES
WILL REMAIN COLDER THAN AVERAGE WITH DRY CONDITIONS EXPECTED.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 149 AM MST SUN NOV 24 2013
THE LARGE SCALE PATTERN SHOWS A LONGWAVE TROUGH OVER THE EASTERN
PORTION OF THE U.S. WITH AN UPPER RIDGE OVER THE ROCKIES.
THROUGHOUT THE EXTENDED...SEVERAL SHORTWAVE TROUGHS IN THE
NORTHWEST/WESTERLY FLOW ALOFT MOVE THROUGH THE NORTHERN
PLAINS...SENDING A FEW WEAK COLD FRONTS THROUGH THE CWA. THE COLD
AIR BEHIND THE FIRST FRONT IS KEPT WELL TO THE NORTH...SO
TEMPERATURES ARE NOT EXPECTED TO FLUCTUATE MUCH BEHIND THE FRONTAL
PASSAGE. THE FIRST FRONT MOVES THROUGH WEDNESDAY NIGHT INTO
THURSDAY AND THE NEXT FRONT...ASSOCIATED WITH WESTERLY/SOUTHWEST
FLOW ALOFT...MOVES THROUGH FRIDAY NIGHT INTO SATURDAY.
TEMPERATURES WITH THE NEXT FRONTAL PASSAGE ALSO ARE NOT EXPECTED
TO FLUCTUATE MUCH SINCE HIGHS SHOULD RECOVER AS THE SURFACE HIGH
QUICKLY PUSHES EAST BY SATURDAY AFTERNOON. FRONTAL PASSAGES WILL
ALSO REMAIN DRY AS THE MAIN FORCING WITH THESE WAVES ALSO REMAINS
NORTH OF THE CWA. TOWARDS THE END OF THE PERIOD...THE LARGE SCALE
PATTERN SHIFTS EAST WITH THE RIDGE FLATTENING AND MOVING OVER THE
CWA THURSDAY THROUGH SATURDAY...WHILE A CLOSED UPPER LOW REMAINS
OVER SOUTHERN CALIFORNIA AND SLOWLY MOVES EAST/SOUTHEAST WITH THE
SOUTHERN STREAM JET MOVING OVER THE CWA ON SATURDAY.
AS PREVIOUSLY MENTIONED...THE EXTENDED PERIOD SHOULD REMAIN
DRY...WITH INCREASING MID TO HIGH CLOUDS WITH FRONTAL PASSAGES.
TEMPERATURES SHOULD REMAIN SEASONABLE...WITH HIGHS IN THE MID 40S TO
LOW 50S AND LOWS IN THE 20S. ONCE EXCEPTION FOR HIGH TEMPERATURES
WILL BE WEDNESDAY...AS SURFACE HIGH PRESSURE OVER EASTERN KANSAS
EXTENDS INTO THE EASTERN PORTION OF THE CWA...FROM RED WILLOW TO
GOVE COUNTY AND EASTWARD...HIGHS COULD ONLY REACH THE UPPER 30S TO
LOW 40S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1034 AM MST SUN NOV 24 2013
VFR CONDITIONS EXPECTED FOR THE PERIOD WITH MAIN CONCERN BEING
STRONG SOUTHERLY WINDS ALONG THE KS AND CO BORDER. GLD WILL
CONTINUE TO SEE SUSTAINED WINDS BETWEEN 22 AND 27 KTS WITH GUSTS TO
4O KTS THROUGH THE NEXT FEW HOURS BEFORE WINDS GRADUALLY DIMINISH.
MCK MAY SEE A BRIEF PERIOD OF GUSTY WINDS...BUT THAT IS EXPECTED
TO BE SHORT LIVED.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WIND ADVISORY UNTIL 4 PM MST /5 PM CST/ THIS AFTERNOON FOR
KSZ001-013-027-041.
CO...WIND ADVISORY UNTIL 4 PM MST THIS AFTERNOON FOR COZ090>092.
NE...WIND ADVISORY UNTIL 4 PM MST THIS AFTERNOON FOR NEZ079.
&&
$$
UPDATE...JRM
SHORT TERM...LOCKHART
LONG TERM...ALW
AVIATION...JRM
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1039 AM MST SUN NOV 24 2013
.UPDATE...
ISSUED AT 904 AM MST SUN NOV 24 2013
WIND GUSTS OF 38 KTS AT LAA AND 41 KTS AT ITR IN THE LAST HOUR
INDICATE BOUNDARY LAYER BEGINNING TO TAP INTO STRONG JET OF LOW
LEVEL WINDS AS PER LATEST RAP AND KGLD VWP. AM A LITTLE CONCERNED
ABOUT AREA OF 50KTS OVER EASTERN COLORADO AT 1 KM AGL...BUT THAT
IS EXPECTED TO WEAKEN OVER THE NEXT 2 HOURS SO DO NOT ANTICIPATE
THE NEED FOR A HIGH WIND WARNING. A WIND ADVISORY DOES APPEAR
NECESSARY AND HAVE ISSUED ONE BASICALLY FOLLOWING EXPECTED CORE OF
STRONGEST 1 KM AGL WINDS THE NEXT FEW HOURS...WITH WINDS EXPECTED
TO DIMINISH IN THE AFTERNOON. MAY SEE SNOW SHOWERS MAKE IT INTO
THIS AREA OF STRONG WINDS...BUT THINK INTENSITY AND DURATION DOES
NOT WARRANT ANY KIND OF PREDOMINANT BLOWING SNOW ADVISORY.
&&
.SHORT TERM...(TODAY AND TUESDAY NIGHT)
ISSUED AT 149 AM MST SUN NOV 24 2013
THE UPPER LEVEL LOW PRESSURE SYSTEM EXPECTED TO AFFECT THE
FORECAST AREA WILL MOVE SLOWLY ACROSS THE DESERT SOUTHWEST AND
SOUTHERN ROCKIES TODAY. AHEAD OF THIS SYSTEM...LIGHT SNOW WILL
SPREAD NORTHWARD OUT OF EASTERN NEW MEXICO AND THE PANHANDLE
REGION OF TEXAS AND OKLAHOMA INTO PORTIONS OF EASTERN COLORADO AND
WESTERN KANSAS. THE BEST CHANCE OF ACCUMULATING SNOWFALL WILL BE
THIS MORNING MAINLY ALONG AND SOUTH OF INTERSTATE 70 WHERE AN INCH
OR LESS OF TOTAL ACCUMULATION IS POSSIBLE.
THE UPPER LOW CENTER WILL PHASE INTO THE MAIN UPPER TROUGH THAT
DEEPENS OVER THE GREAT LAKES AND MISSISSIPPI VALLEY REGION
TONIGHT. THE LOW WILL THEN BEGIN TO MOVE SOUTHEASTWARD OVER TEXAS
WITH DRYER AIR ALOFT AND SUBSIDENCE MOVING OVER THE CENTRAL HIGH
PLAINS REGION TONIGHT. THE UPPER RIDGE AMPLIFYING OVER THE WESTERN
UNITED STATES MOVES OVER THE INTERMOUNTAIN REGION MONDAY NIGHT AND
TUESDAY AND BEGINS TO MOVE OVER THE ROCKIES ON TUESDAY NIGHT.
ALTHOUGH TEMPERATURES WILL BE GRADUALLY INCREASING THROUGH THE
FIRST PART OF THE WORK WEEK AS HIGH PRESSURE MOVES INTO THE
REGION...MODEL TRENDS HAVE BEEN CONSISTENTLY LOWERING TEMPERATURES
WITH EACH SUBSEQUENT MODEL RUN OVER THE PAST FEW DAYS. TEMPERATURES
WILL REMAIN COLDER THAN AVERAGE WITH DRY CONDITIONS EXPECTED.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 149 AM MST SUN NOV 24 2013
THE LARGE SCALE PATTERN SHOWS A LONGWAVE TROUGH OVER THE EASTERN
PORTION OF THE U.S. WITH AN UPPER RIDGE OVER THE ROCKIES.
THROUGHOUT THE EXTENDED...SEVERAL SHORTWAVE TROUGHS IN THE
NORTHWEST/WESTERLY FLOW ALOFT MOVE THROUGH THE NORTHERN
PLAINS...SENDING A FEW WEAK COLD FRONTS THROUGH THE CWA. THE COLD
AIR BEHIND THE FIRST FRONT IS KEPT WELL TO THE NORTH...SO
TEMPERATURES ARE NOT EXPECTED TO FLUCTUATE MUCH BEHIND THE FRONTAL
PASSAGE. THE FIRST FRONT MOVES THROUGH WEDNESDAY NIGHT INTO
THURSDAY AND THE NEXT FRONT...ASSOCIATED WITH WESTERLY/SOUTHWEST
FLOW ALOFT...MOVES THROUGH FRIDAY NIGHT INTO SATURDAY.
TEMPERATURES WITH THE NEXT FRONTAL PASSAGE ALSO ARE NOT EXPECTED
TO FLUCTUATE MUCH SINCE HIGHS SHOULD RECOVER AS THE SURFACE HIGH
QUICKLY PUSHES EAST BY SATURDAY AFTERNOON. FRONTAL PASSAGES WILL
ALSO REMAIN DRY AS THE MAIN FORCING WITH THESE WAVES ALSO REMAINS
NORTH OF THE CWA. TOWARDS THE END OF THE PERIOD...THE LARGE SCALE
PATTERN SHIFTS EAST WITH THE RIDGE FLATTENING AND MOVING OVER THE
CWA THURSDAY THROUGH SATURDAY...WHILE A CLOSED UPPER LOW REMAINS
OVER SOUTHERN CALIFORNIA AND SLOWLY MOVES EAST/SOUTHEAST WITH THE
SOUTHERN STREAM JET MOVING OVER THE CWA ON SATURDAY.
AS PREVIOUSLY MENTIONED...THE EXTENDED PERIOD SHOULD REMAIN
DRY...WITH INCREASING MID TO HIGH CLOUDS WITH FRONTAL PASSAGES.
TEMPERATURES SHOULD REMAIN SEASONABLE...WITH HIGHS IN THE MID 40S TO
LOW 50S AND LOWS IN THE 20S. ONCE EXCEPTION FOR HIGH TEMPERATURES
WILL BE WEDNESDAY...AS SURFACE HIGH PRESSURE OVER EASTERN KANSAS
EXTENDS INTO THE EASTERN PORTION OF THE CWA...FROM RED WILLOW TO
GOVE COUNTY AND EASTWARD...HIGHS COULD ONLY REACH THE UPPER 30S TO
LOW 40S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1034 AM MST SUN NOV 24 2013
VFR CONDITIONS EXPECTED FOR THE PERIOD WITH MAIN CONCERN BEING
STRONG SOUTHERLY WINDS ALONG THE KS AND CO BORDER. GLD WILL
CONTINUE TO SEE SUSTAINED WINDS BETWEEN 22 AND 27 KTS WITH GUSTS TO
4O KTS THROUGH THE NEXT FEW HOURS BEFORE WINDS GRADUALLY DIMINISH.
MCK MAY SEE A BRIEF PERIOD OF GUSTY WINDS...BUT THAT IS EXPECTED
TO BE SHORT LIVED.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WIND ADVISORY UNTIL 4 PM MST /5 PM CST/ THIS AFTERNOON FOR
KSZ001-013.
CO...WIND ADVISORY UNTIL 4 PM MST THIS AFTERNOON FOR COZ090>092.
NE...WIND ADVISORY UNTIL 4 PM MST THIS AFTERNOON FOR NEZ079.
&&
$$
UPDATE...JRM
SHORT TERM...LOCKHART
LONG TERM...ALW
AVIATION...JRM
AREA FORECAST DISCUSSION
NWS GOODLAND KS
909 AM MST SUN NOV 24 2013
.UPDATE...
ISSUED AT 904 AM MST SUN NOV 24 2013
WIND GUSTS OF 38 KTS AT LAA AND 41 KTS AT ITR IN THE LAST HOUR
INDICATE BOUNDARY LAYER BEGINNING TO TAP INTO STRONG JET OF LOW
LEVEL WINDS AS PER LATEST RAP AND KGLD VWP. AM A LITTLE CONCERNED
ABOUT AREA OF 50KTS OVER EASTERN COLORADO AT 1 KM AGL...BUT THAT
IS EXPECTED TO WEAKEN OVER THE NEXT 2 HOURS SO DO NOT ANTICIPATE
THE NEED FOR A HIGH WIND WARNING. A WIND ADVISORY DOES APPEAR
NECESSARY AND HAVE ISSUED ONE BASICALLY FOLLOWING EXPECTED CORE OF
STRONGEST 1 KM AGL WINDS THE NEXT FEW HOURS...WITH WINDS EXPECTED
TO DIMINISH IN THE AFTERNOON. MAY SEE SNOW SHOWERS MAKE IT INTO
THIS AREA OF STRONG WINDS...BUT THINK INTENSITY AND DURATION DOES
NOT WARRANT ANY KIND OF PREDOMINANT BLOWING SNOW ADVISORY.
&&
.SHORT TERM...(TODAY AND TUESDAY NIGHT)
ISSUED AT 149 AM MST SUN NOV 24 2013
THE UPPER LEVEL LOW PRESSURE SYSTEM EXPECTED TO AFFECT THE
FORECAST AREA WILL MOVE SLOWLY ACROSS THE DESERT SOUTHWEST AND
SOUTHERN ROCKIES TODAY. AHEAD OF THIS SYSTEM...LIGHT SNOW WILL
SPREAD NORTHWARD OUT OF EASTERN NEW MEXICO AND THE PANHANDLE
REGION OF TEXAS AND OKLAHOMA INTO PORTIONS OF EASTERN COLORADO AND
WESTERN KANSAS. THE BEST CHANCE OF ACCUMULATING SNOWFALL WILL BE
THIS MORNING MAINLY ALONG AND SOUTH OF INTERSTATE 70 WHERE AN INCH
OR LESS OF TOTAL ACCUMULATION IS POSSIBLE.
THE UPPER LOW CENTER WILL PHASE INTO THE MAIN UPPER TROUGH THAT
DEEPENS OVER THE GREAT LAKES AND MISSISSIPPI VALLEY REGION
TONIGHT. THE LOW WILL THEN BEGIN TO MOVE SOUTHEASTWARD OVER TEXAS
WITH DRYER AIR ALOFT AND SUBSIDENCE MOVING OVER THE CENTRAL HIGH
PLAINS REGION TONIGHT. THE UPPER RIDGE AMPLIFYING OVER THE WESTERN
UNITED STATES MOVES OVER THE INTERMOUNTAIN REGION MONDAY NIGHT AND
TUESDAY AND BEGINS TO MOVE OVER THE ROCKIES ON TUESDAY NIGHT.
ALTHOUGH TEMPERATURES WILL BE GRADUALLY INCREASING THROUGH THE
FIRST PART OF THE WORK WEEK AS HIGH PRESSURE MOVES INTO THE
REGION...MODEL TRENDS HAVE BEEN CONSISTENTLY LOWERING TEMPERATURES
WITH EACH SUBSEQUENT MODEL RUN OVER THE PAST FEW DAYS. TEMPERATURES
WILL REMAIN COLDER THAN AVERAGE WITH DRY CONDITIONS EXPECTED.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 149 AM MST SUN NOV 24 2013
THE LARGE SCALE PATTERN SHOWS A LONGWAVE TROUGH OVER THE EASTERN
PORTION OF THE U.S. WITH AN UPPER RIDGE OVER THE ROCKIES.
THROUGHOUT THE EXTENDED...SEVERAL SHORTWAVE TROUGHS IN THE
NORTHWEST/WESTERLY FLOW ALOFT MOVE THROUGH THE NORTHERN
PLAINS...SENDING A FEW WEAK COLD FRONTS THROUGH THE CWA. THE COLD
AIR BEHIND THE FIRST FRONT IS KEPT WELL TO THE NORTH...SO
TEMPERATURES ARE NOT EXPECTED TO FLUCTUATE MUCH BEHIND THE FRONTAL
PASSAGE. THE FIRST FRONT MOVES THROUGH WEDNESDAY NIGHT INTO
THURSDAY AND THE NEXT FRONT...ASSOCIATED WITH WESTERLY/SOUTHWEST
FLOW ALOFT...MOVES THROUGH FRIDAY NIGHT INTO SATURDAY.
TEMPERATURES WITH THE NEXT FRONTAL PASSAGE ALSO ARE NOT EXPECTED
TO FLUCTUATE MUCH SINCE HIGHS SHOULD RECOVER AS THE SURFACE HIGH
QUICKLY PUSHES EAST BY SATURDAY AFTERNOON. FRONTAL PASSAGES WILL
ALSO REMAIN DRY AS THE MAIN FORCING WITH THESE WAVES ALSO REMAINS
NORTH OF THE CWA. TOWARDS THE END OF THE PERIOD...THE LARGE SCALE
PATTERN SHIFTS EAST WITH THE RIDGE FLATTENING AND MOVING OVER THE
CWA THURSDAY THROUGH SATURDAY...WHILE A CLOSED UPPER LOW REMAINS
OVER SOUTHERN CALIFORNIA AND SLOWLY MOVES EAST/SOUTHEAST WITH THE
SOUTHERN STREAM JET MOVING OVER THE CWA ON SATURDAY.
AS PREVIOUSLY MENTIONED...THE EXTENDED PERIOD SHOULD REMAIN
DRY...WITH INCREASING MID TO HIGH CLOUDS WITH FRONTAL PASSAGES.
TEMPERATURES SHOULD REMAIN SEASONABLE...WITH HIGHS IN THE MID 40S TO
LOW 50S AND LOWS IN THE 20S. ONCE EXCEPTION FOR HIGH TEMPERATURES
WILL BE WEDNESDAY...AS SURFACE HIGH PRESSURE OVER EASTERN KANSAS
EXTENDS INTO THE EASTERN PORTION OF THE CWA...FROM RED WILLOW TO
GOVE COUNTY AND EASTWARD...HIGHS COULD ONLY REACH THE UPPER 30S TO
LOW 40S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 440 AM MST SUN NOV 24 2013
CURRENTLY IT LOOKS LIKE VFR CONDITIONS WILL PREVAIL THROUGH THE
TAF PERIOD. CEILINGS AT KGLD ONLY REDUCED TO BKN060 IN THE LAST
FEW HOURS AS THE FIRST WEAK BAND OF LIGHT SNOW MOVED OVER THE TAF
SITE. SOUNDINGS EARLIER THIS MORNING INDICATED POSSIBLY LOWER
CEILINGS WITH A CONTINUING CHANCE OF LIGHT SNOW LATER THIS
MORNING. AFTER VIEWING RAP SOUNDINGS...IT APPEARS THAT THIS IS NO
LONGER THE CASE. GUIDANCE ALSO DID NOT INCLUDE LOWERED CEILINGS
BEYOND VFR. LOW CONFIDENCE IN THE FORECAST AS OF RIGHT NOW...WILL
MAKE ANY AMMENDMENTS IF AND WHEN NECESSARY. SOUTHERLY WINDS WILL
PICK UP TODAY TO AROUND 15 TO 25 KTS GUSTING FROM 25 TO 35 KTS.
WIND GUSTS SHOULD DIMINISH OVERNIGHT WITH A WIND SHIFT TO THE
NORTHWEST. OVERCAST AND BROKEN CEILINGS SHOULD BECOME SCATTERED
OVERNIGHT AS THE THE STORM SYSTEM SOUTH OF THE AREA MOVES
NORTH/NORTHEAST.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WIND ADVISORY UNTIL 4 PM MST /5 PM CST/ THIS AFTERNOON FOR
KSZ001-013.
CO...WIND ADVISORY UNTIL 4 PM MST THIS AFTERNOON FOR COZ090>092.
NE...WIND ADVISORY UNTIL 4 PM MST THIS AFTERNOON FOR NEZ079.
&&
$$
UPDATE...JRM
SHORT TERM...LOCKHART
LONG TERM...ALW
AVIATION...ALW
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1211 PM EST SUN NOV 24 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 526 AM EST SUN NOV 24 2013
WV IMAGERY AND RUC ANALYSIS INDICATED NW MID/UPPER LEVEL FLOW
THROUGH THE NRN GREAT LAKES WITH GRADUALLY RISING HEIGHTS AS THE
TROUGH OVER THE NE CONUS SLIDES TO THE EAST AND MID LEVEL RIDGING
BUILDS TOWARD THE AREA FROM SOUTH CENTRAL CANADA. AT THE SFC...A
RIDGE WAS BUILDING FROM NW WI AND WRN LAKE SUPERIOR INTO FAR W UPPER
MI WHILE LAKE INDUCED TROUGHING PREVAILED THROUGH ERN LAKE SUPERIOR.
SATELLITE AND RADAR INDICATED NW-SE ALIGNED WIND PARALLEL LES BANDS
HAD SHIFTED INTO LOCATIONS E OF MARQUETTE COUNTY. THE BANDS HAD
ALSO BECOME MORE CELLULAR WITH GRADUALLY DECREASING INTENSITY
OVERNIGHT. SFC OBS STILL INDICATED INTO W UPPER MI WITH CMX SHOWING
VSBY IN THE 1-3SM RANGE. HOWEVER...WEBCAMS FROM HOUGHTON AND CALUMET
SHOWED LITTLE SNOW OR VSBY REDUCTION.
THIS MORNING...
DESPITE 850 MB TEMPS AROUND -20C...INVERSION HEIGHTS DROPPING BELOW
5K FT AND VERY DRY AIR UPSTREAM WILL CONTINUE TO LIMIT LES
INTENSITY...ESPECIALLY OVER THE WEST. DIMINISHING WINDS WITH AN
INCREASED LAND BREEZE INFLUENCE AND A BACKING TREND WITH THE
APPROACHING RIDGE WILL RESULT IN A PERIOD OF ENHANCED CONVERGENCE
FROM ERN LAKE SUPERIOR INTO UPPER MI BETWEEN MUNISING AND NEWBERRY
WHERE ADDITIONAL SNOW AMOUNTS IN THE 1 TO 3 INCH RANGE ARE EXPECTED
THROUGH THE MORNING. THE BACKING WINDS SHOULD PUSH THE REMAINING LES
OFFSHORE IN THE AFTERNOON.
THIS AFTERNOON AND TONIGHT...
DEVELOPING WAA WITH STRONG 280K-295K PRES ADV BUT ONLY WEAK TO
MODERATE NET LIFT AHEAD OF A SHRTWV AND SFC LOW MOVING INTO CNTRL
MANITOBA MAY LEAD TO AN AREA OF LIGHT SNOW STREAKING SE INTO THE
NORTH AND EAST PORTIONS OF UPPER MI LATE THIS AFTERNOON AND EVENING.
HOWEVER...WITH THE DRY LOW LEVELS...LITTLE IF ANY SNOW ACCUMULATION
IS EXPECTED WITH ONLY SLIGHT CHANCE POPS INCLUDED. SNOW CHANCES WILL
INCREASE OVERNIGHT AS 700-300 MB QVECTOR CONV AHEAD OF THE SHORTWAVE
MOVES IN BUT SNOW AMOUNTS SHOULD REMAIN LESS THAN A HALF INCH. SW
FLOW LAKE ENHANCEMENT IS LIKELY TO DEVELOP OFF OF LAKE MICHIGAN BUT
THE LOW LEVEL WINDS VEER ENOUGH TO KEEP THE HIGHER SNOW
CHANCES/AMOUNTS TO THE SOUTH AND EAST OF SCHOOLCRAFT AND LUCE
COUNTIES.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 440 AM EST SUN NOV 24 2013
NORTHERN STREAM REMAINS ACTIVE THROUGH THE WEEK KEEPING THE COLD
ACROSS THE GREAT LAKES. NEXT CHARGE OF ARCTIC AIR ARRIVES LATER
MONDAY NIGHT INTO TUESDAY. LK EFFECT SNOW INCREASES MONDAY NIGHT
THROUGH TUESDAY NIGHT. AFTER HIGH PRESSURE RIDGE/SUBSIDENCE BRINGS
DIMINISHING TREND TO LK EFFECT LATER WEDNESDAY...ANOTHER SHORTWAVE
DROPPING THROUGH MAY BRING SOME LGT SNOW FOR THANKSGIVING DAY.
AGREEMENT FALLS OFF BY NEXT WEEKEND WITH THE ECMWF KEEPING A NW FLOW
ALOFT ACROSS GREAT LAKES AND BRINGING ANOTHER CLIPPER THROUGH ON
SATURDAY. GFS IS SLOWER AND MORE DEVELOPED BUT FARTHER NORTH WITH
NEXT TROUGH DROPPING THROUGH BY LATE IN THE WEEKEND.
MODELS IN OKAY AGREEMENT THROUGH 12Z TUESDAY THEN THEY BEGIN TO SHOW
DIFFERENCES. OVERALL THOUGH EVEN THE DISAGREEMENT...SPEED OF INITIAL
SHORTWAVE MOVING THROUGH UPR LAKES...DOES NOT HAVE HUGE IMPACTS ON
THE OVERALL THEME OF FORECAST. GFS ENDS UP BEING QUICKER THAN
ECMWF/NAM AND GEM-NH WITH HANDLING OF INITIAL SHORTWAVE. PLAN IS
THAT ON MONDAY MORNING SHORTWAVE WILL BE NORTH OF LK SUPERIOR WITH
TROUGH AXIS DROPPING ACROSS UPR LAKES. SFC LOW/H85 LOW AND SFC
TROUGH SWINGS ACROSS WESTERN UPR MICHIGAN BY MIDDAY AND INTO THE
EASTERN CWA BY EVENING. MAY SEE LGT LK EFFECT WITH MARGINAL TEMPS
AT INVERSION TOP MOST OF THE DAY OVER THE WEST...BETTER CHANCES WILL
BE LATER ON THOUGH. HINT THAT WEAK WAVE IN THE SOUTHERN STREAM
SLIDES WSW-ENE ACROSS MAINLY SOUTHERN SECTIONS OF WESTERN GREAT
LAKES AND INTERACTS WITH H8-H7 FRONTOGENESIS AND RIGHT ENTRANCE
REGION OF JET FM CNTRL GREAT LAKES TO SOUTHERN QUEBEC MONDAY MORNING
THROUGH MID MONDAY AFTN. SOME LGT SYNOPTIC SNOW MAY SCRAPE LK
MICHIGAN ZONES AND FAR EAST. IF THERE IS ENOUGH LOW-LEVEL MOISTURE
TO START THE DAY...COULD EVEN SEE A BIT OF FZDZ ALONG WI BORDER AS
DEEPER MOISTURE HEADS EAST. LAKE ENHANCEMENT EXPECTED OFF LK
MICHIGAN WITH SW FLOW AS H85 TEMPS ARE AROUND -8C. SHOULD STAY
EAST OF CWA THOUGH AS WINDS ARE FM SW INSTEAD OF SSW OR S. FARTHER
WEST...LK EFFECT SHOULD INCREASE LATER AFTN OVER WESTERN THIRD OF
CWA AS SYNOPTIC LIFT /-DIV-Q AT H7-H5/ FM APPROACHING SHORTWAVE
COMBINES WITH WNW WINDS THROUGH H85 AND TEMPS AT H85 OF -8C YIELDING
DELTA T/S UP TO 12C. INSTABILITY IS MARGINAL AND THUS EXPECT ONLY
MINOR SNOW ACCUMS THROUGH 00Z TUESDAY IN THE WEST.
MONDAY NIGHT INTO TUESDAY HOLDS GREATEST CHANCE FOR MODERATE TO
HEAVY LK EFFECT SNOW SHOWERS. OVERALL EXPECT MOST SNOW TO OCCUR FOR
AREAS FAVORED BY NNW WINDS THROUGH TUESDAY AND THEN SHIFT TO AREAS
FAVORED BY N OR NE WINDS ON TUESDAY NIGHT. UNLIKE THIS LAST EVENT
WHERE SNOWFALL AMOUNTS ENDED UP ON THE LOWER END OF FCST FOR MOST
AREAS...SHORTWAVE/ADDITIONAL SYNOPTIC MOISTURE IS FCST TO IMPACT UPR
LAKES DURING THE TIME OF THE LAKE EFFECT...ESPECIALLY THROUGH
TUESDAY. AT THE LEAST...EXPECT ADVY TYPE SNOWS WILL OCCUR FOR MAINLY
NNW-NW FLOW AREAS MONDAY NIGHT INTO TUESDAY. LACK OF PERSISTENT
UNIDIRECTIONAL FLOW IN LAKE EFFECT CONVECTIVE LAYER WILL LIMIT SNOW
AMOUNTS THOUGH THIS WILL PROBABLY BE OFFSET BY THE SHORTWAVE/DEEPER
MOISTURE. SEEMS LIKE HIGHER TERRAIN FROM IRONWOOD TO ROCKLAND TO
PAINESDALE AND ATLANTIC MINE WILL SEE THE MOST SNOW OVER THE WEST
WHILE FAVORED SNOWBELTS FROM EAST OF MARQUETTE TO NEWBERRY...
INCLUDING MOST OF ALGER COUNTY AND ALONG AND NORTH OF THE SENEY
STRETCH IN SCHOOLCRAFT COUNTY...WILL SEE THE MOST SNOW OVER THE CNTRL
AND EASTERN CWA. UNLIKE THIS LAST EVENT...WINDS SEEM MORE CERTAIN TO
VEER ENOUGH NORTHERLY TO ALLOW FOR LK EFFECT SNOWS TO IMPACT NCNTRL
UPR MICHIGAN /HIGHER TERRAIN OF BARAGA AND MARQUETTE COUNTIES/ LATER
TUESDAY INTO TUESDAY NIGHT AND PERHAPS LINGERING INTO MOST OF
WEDNESDAY. INVERSIONS LOWERING BLO 5KFT AND WINDS BECOMING VARIABLE
WILL DIMINISH SNOW OVER FAR WEST BY WEDNESDAY AFTN. A LIGHT BUT
PERSISTENT N-NE WIND MAY KEEP WEAKENING SNOW SHOWERS GOING THROUGH
MOST OF THE NIGHT BTWN MQT AND MUNISING. LIGHTER WINDS PROBABLY WILL
KEEP MOST OF SNOW SHOWERS RIGHT ALONG IMMEDIATE SHORE WITH SKIES
TRYING TO CLEAR OUT INLAND.
SHORTWAVE AND ARC OF WARM AIR ADVECTION/MOISTURE ADVECTION COULD
SPUR ON BATCH OF LGT SNOW ACROSS MAINLY NORTHERN CWA DURING THE DAY
ON THANKSGIVING. LIMITED MOISTURE WITH PWATS LESS THAN 100 PCT OF
NORMAL AND FOCUS OF STRONGER LIFT FM SHORTWAVE STAYING NORTH OF LK
SUPERIOR SHOULD LIMIT SNOW AMOUNTS. TROUGH SWINGING ACROSS NORTHERN
UPR MICHIGAN MAY KICK OFF SOME SNOW SHOWERS ACROSS KEWEENAW LATER
THURSDAY NIGHT INTO FRIDAY. CONSENSUS GIVES LOW CHANCE POPS BEYOND
FRIDAY WHICH IS FINE GIVEN DIFFERENCES IN TRACK OF SHORTWAVE/SFC
SYSTEM THAT GFS/ECMWF INDICATE MOVES THROUGH THE AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1210 PM EST SUN NOV 24 2013
VFR CONDITIONS WILL CONTINUE THROUGH MOST OF TONIGHT AT ALL SITES AS
HIGH PRESSURE IS OVER THE AREA. THE PRESSURE GRADIENT OVER THE AREA
WILL TIGHTEN THIS AFTERNOON AND EVENING...SO EXPECT A GUSTY WIND TO
DEVELOP AT THE MORE EXPOSED IWD AND SAW LOCATIONS. MVFR CONDITIONS
WILL RETURN LATE TONIGHT AS LOW LEVEL MOISTURE INCREASES AHEAD OF A
TROUGH APPROACHING THE AREA AT CMX AND IWD AND WILL RETURN MON
MORNING AT SAW. DID PUT IN SOME LLWS AT IWD TONIGHT WITH STRONG
WINDS OFF THE SURFACE. WILL GET QUITE GUSTY AT CMX WITH FAVORABLE
WEST WINDS MONDAY MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 440 AM EST SUN NOV 24 2013
NW WINDS TO 25 KTS DIMINISH THIS MORNING THEN SHIFT TO THE SW AND
INCREASE TO 30 KTS THIS EVENING. GALES EXPECTED OVR SUPERIOR ZONE
263 TONIGHT DUE TO CHANNELED FLOW BTWN KEWEENAW AND ISLE ROYALE.
WINDS TURN TO NORTHWEST ON MONDAY INTO TUESDAY AND REMAIN UP TO 30
KTS. FREEZING SPRAY MAY OCCUR LATER MONDAY INTO TUESDAY AS ANOTHER
PUSH OF COLDER AIR CROSSES LK SUPERIOR. GALE GUSTS POSSIBLE AS THE
COLDER AIR FIRST ARRIVES. EVENTUALLY WINDS BECOME NORTHERLY TUESDAY
NIGHT INTO WEDNESDAY THEN DIMINISH TO LESS THAN 20 KTS THROUGH THE
REST OF THE WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 5 PM THIS AFTERNOON TO 8 AM EST MONDAY FOR
LSZ263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...07
MARINE...JLA
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
236 PM CST SUN NOV 24 2013
.SYNOPSIS...
ISSUED AT 235 PM CST SUN NOV 24 2013
AN UPPER LOW SPUN OVER THE FOUR CORNERS ON SUNDAY AFTERNOON...WHICH
PUSHED SOME MID AND HIGH LEVEL CLOUDS INTO SOUTHERN NEBRASKA. WITH
THE UPPER LOW TO THE SOUTH...WESTERLY FLOW ALOFT HAS ALLOWED FOR A
THERMAL RIDGE TO MOVE INTO THE NORTHERN PLAINS TODAY WHERE 850MB
TEMPERATURES WERE GENERALLY 5C TO 10C AS OF 12Z THIS MORNING
COMPARED TO 0C TO-5C ACROSS NEBRASKA. LOOKING AT WATER VAPOR...COULD
MAKE OUT THE NEXT LOW PRESSURE SYSTEM IN LINE IN THE NORTHWEST FLOW
OVER SASKATCHEWAN...WITH ANOTHER BATCH OF COLD ARCTIC AIR BEHIND IT.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 235 PM CST SUN NOV 24 2013
THE UPPER LEVEL LOW OVER THE FOUR CORNERS IS EXPECTED TO START
GETTING INFLUENCED BY THE MEAN NORTHWEST FLOW AND START TO PUSH INTO
TEXAS BY THE END OF THE DAY MONDAY. THIS SHOULD ALLOW FOR THE MID
AND HIGH CLOUDS THAT HAVE BEEN SPINNING AROUND THIS SYSTEM INTO THE
SOUTHERN PART OF THE FORECAST AREA FOR THE PAST SEVERAL DAYS TO GET
PULLED SOUTHWARD AND AWAY FROM THE LOCAL AREA TONIGHT AND MONDAY
MORNING. IT WILL ALSO ALLOW FOR SOME OF THE COLDER AIR ASSOCIATED
WITH THAT SYSTEM TO GET PUSHED AWAY FROM THE AREA. MEANWHILE...THE
LOW PRESSURE SYSTEM OVER SASKATCHEWAN WILL MOVE INTO ONTARIO WHICH
WILL DRAG A COLD FRONT ACROSS NEBRASKA TONIGHT AND MONDAY MORNING.
ALTHOUGH TEMPERATURES BEHIND THE FRONT WON/T BE MUCH COLDER FOR THE
LOCAL AREA. WINDS WILL SWITCH TO THE NORTH-NORTHWEST BEHIND THE
FRONT. FORECAST SOUNDINGS ARE SHOWING MINIMAL MIXING MONDAY
AFTERNOON...BUT WINDS JUST ABOVE THE SURFACE ARE ABOUT 25KTS SO
COULD SEE SOME 20KT WINDS AT GROUND LEVEL DURING THE AFTERNOON.
ONE CONCERN WITH THE FORECAST WILL BE THE POTENTIAL FOR THE
DEVELOPMENT OF SHALLOW STRATUS THIS EVENING AND TONIGHT FROM
SOUTHWEST INTO CENTRAL NEBRASKA. LOW LEVEL MOISTURE ADVECTION IS
BEING INDICATED INTO THE AREA AHEAD OF THE FRONT BY SEVERAL FORECAST
MODELS...WITH THE NAM BEING THE MOST ROBUST SPREADING STRATUS ACROSS
THE ENTIRE FORECAST AREA. DISCOUNTING THAT MODEL AND LOOKING CLOSER
TO THE RAP WHICH HAS BEEN HOLDING OFF THE LOW LEVEL MOISTURE FROM
MOVING INTO NEBRASKA THROUGH THE DAY TODAY. ALTHOUGH IT HAS KEPT
THIS MOISTURE SOUTH TODAY...IT DOES CONTINUE TO PUSH IT INTO
NEBRASKA THIS EVENING...WITH CLOUDS REMAINING UNTIL THE FRONT PUSHES
THROUGH LATE TONIGHT AND MONDAY MORNING. WATCHING THE STRATUS
STRUGGLE TO DEVELOP IN UPSTREAM AREAS TODAY...AND WITH THE RAP
CONTINUOUSLY BACKING OFF ON THE TIMING OF BRINGING IT NORTH...JUST
DON/T HAVE THE CONFIDENCE THAT THE CLOUDS WILL GET INTO THE LOCAL
AREA TONIGHT AND THE FORECAST TAKES THAT INTO ACCOUNT. IF THE
STRATUS DOES MOVE IN...MAY HAVE TO TAKE A LOOK AT LOW TEMPERATURES
TONIGHT...ALTHOUGH THEY SHOULDN/T HAVE AN IMPACT ON HIGHS MONDAY AS
THEY WOULD BE PUSHED OUT OF THE AREA BEFORE PEAK HEATING.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 235 PM CST SUN NOV 24 2013
A REINFORCING SHOT OF ARCTIC AIR WILL MOVE THROUGH THE DAKOTAS
INTO NEBRASKA MONDAY NIGHT AND TUESDAY. THIS WILL BRING A GLANCING
BLOW OF COLDER AIR...WHICH IS ACTUALLY NOT AS COLD AS THE PREVIOUS
ONE SATURDAY. WENT A FEW DEGREES ABOVE GUIDANCE LOWS MONDAY NIGHT
WITH MID/UPPER TEENS. WEAK COLD AIR ADVECTION TUESDAY WITH H85
TEMPS AS LOW AS -15C PER NAM MODEL. THIS LOOK TOO COLD AND FAVORED
THE GFS -11C. USING CONSALL INTO A BLEND HIGHS NEAR 25 AT ONL TO
36 AT IML. TEMPERATURES THEN WARMUP FOR WEDNESDAY. AS SURFACE HIGH
SLIDES EAST...A RETURN SOUTH TO SOUTHWEST FLOW DEVELOPS. WHILE
HIGHS TO BE LIMITED TO NEAR 30 AT BBW AND ONL...THE WESTERN TIER
OF COUNTIES TO WARM TO 40-43 DEGREES. DRY CONDITIONS TO ALSO PREVAIL.
FOR THANKSGIVING DAY THROUGH THE WEEKEND...DRY AND SEASONAL
TEMPERATURES ARE FORECAST. THE UPPER FLOW WILL REMAIN FAIRLY
ZONAL. THIS HIGHLIGHTED BY AN UPPER TROUGH DIGGING FROM BRITISH
COLUMBIA INTO THE NORTHERN PLAINS AND A CLOSED LOW REMAINING OFF
THE CALIF. COAST. ONLY A WEAK COLD FRONT INDICATED FRIDAY
NIGHT...WHICH SHOULD HAVE MINIMAL IMPACT TO HIGHS SATURDAY AND
SUNDAY. ONLY VERY MINOR CHANGES TO HIGHS THROUGH THIS WEEKEND WITH
MAINLY UPPER 30S TO MID 40S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1225 PM CST SUN NOV 24 2013
WINDS WILL BE BREEZY FROM THE SOUTH-SOUTHWEST THROUGH THE
AFTERNOON. WINDS WILL DIMINISH BY 00Z...THEN WILL SWITCH TO THE
NORTHWEST OVERNIGHT AS A WEAK FRONT MOVES ACROSS WESTERN
NEBRASKA. LOOK FOR THE WINDS TO INCREASE THEN BY LATE MONDAY
MORNING...WHERE GUSTS COULD REACH 20KTS INTO THE AFTERNOON. THERE
CONTINUES TO BE INDICATION OF STRATUS DEVELOPMENT INTO SOUTHWEST
NEBRASKA TONIGHT /PRIMARILY IMPACTING KLBF/ AS MODELS ARE SHOWING A
SHALLOW LAYER OF MOISTURE IN THE BOUNDARY LAYER MOVING INTO THE
AREA. THE MODELS HAVE BEEN HAVING SOME PROBLEMS HANDLING THIS LOW
LEVEL MOISTURE OVER THE LAST SEVERAL DAYS SO DON/T HAVE MUCH
CONFIDENCE IN THAT SOLUTION AND LEFT THE MVFR CEILINGS OUT OF THE
FORECAST FOR NOW. WILL KEEP A WATCH ON THIS THROUGH THE AFTERNOON.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BROOKS
SHORT TERM...BROOKS
LONG TERM...ROBERG
AVIATION...BROOKS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1225 PM CST SUN NOV 24 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 323 AM CST SUN NOV 24 2013
1045 MB ARCTIC HIGH PRESSURE CENTERED NEAR KANSAS CITY WILL MOVE
RAPIDLY EAST THROUGH THE MIDSOUTH TODAY AND BE LOCATED OVER NORTH
CAROLINA BY MONDAY MORNING.
THE MODELS INSIST STRATUS WILL FORM IN THE RETURN FLOW SETTING
ACROSS SWRN NEB. AT 08Z THE NEAREST STRATUS WAS OVER NW TEX...ABOUT
500 MILES SOUTH OF THE FORECAST POSITION OF THE MODEL CONSENSUS. NO
STRATUS IS EXPECTED TO DEVELOP AT THIS TIME BUT MID LEVEL CLOUDS
ACROSS ERN COLO/WRN KS ARE EXPECTED TO LIFT NORTH PART WAY THROUGH
THE FCST AREA AND THEN GET SHUNTED EAST WITH THE APPROACH OF A NRN
STREAM SHORTWAVE THIS EVENING. TEMPERATURES ARE EXPECTED TO RISE
INTO THE 30S TO AROUND 40. WARMER GUIDANCE WAS USED FOR THE FORECAST
OWING TO THE CONTAMINATION IN THE SKY COVER SHOWN BY MOST MODELS.
FOR TONIGHT A COLD FRONT WILL BE MOVING SOUTH THROUGH THE NRN HIGH
PLAINS. A THERMAL RIDGE WILL BE RUNNING OUT AHEAD OF THE COLD FRONT
WHICH WILL LIKELY PRODUCE THE COOLEST LOWS IN THE SOUTH BEFORE THE
WIND SHIFT DEVELOPS LATE TONIGHT. THUS LOWS IN THE TEENS ARE
EXPECTED SOUTH WITH 20S NORTH.
SOUTH AND SOUTHWEST WINDS TODAY INCREASE TO 15 TO 25 MPH. LOW
PRESSURE CURRENTLY ACROSS GREAT SLAVE LAKE WILL DIVE SOUTHEAST
TOWARD LAKE SUPERIOR TODAY AND TONIGHT. THE 500M AGL WINDS IN THE
NAM AND RAP MODELS INCREASE TO NEAR 30 MPH AT THE SFC EAST OF
HIGHWAY 183. THIS WOULD SUPPORT GUSTS TO 35 MPH BUT LIMITED VERTICAL
MIXING IN COOL RETURN FLOW SHOULD LIMIT SUSTAINED WIND SPEEDS TO 25
MPH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 323 AM CST SUN NOV 24 2013
A SLOW MOVING UPPER LEVEL LOW PRESSURE SYSTEM WILL MIGRATE FROM
ARIZONA TO WEST TEXAS BY MONDAY. MEANWHILE ANOTHER POTENT
SHORTWAVE TROUGH WILL DIVE SOUTHEAST THROUGH CENTRAL
CANADA...REACHING THE GREAT LAKES BY TUESDAY EVENING. THE
SOUTHERN PLAINS LOW AND GREAT LAKES TROUGH WILL EVENTUALLY
PHASE TO OUR EAST...AND BRING HEAVY PRECIPITATION ALONG THE EAST
COAST WEDNESDAY AND WEDNESDAY NIGHT. AS MENTIONED...THE MAJORITY
OF THE WEATHER WITH THESE SYSTEMS REMAINS TO OUR EAST...BUT A COLD
FRONT WILL DROP SOUTH THROUGH THE AREA TUESDAY. THIS WILL BRING
ANOTHER REINFORCING SHOT OF ARCTIC AIR TO THE REGION. THE BRUNT OF
THE ARCTIC AIR WILL BE FELT ACROSS THE MISSOURI RIVER
VALLEY...WHERE HIGHS IN THE 20S ARE EXPECTED. FARTHER WEST ACROSS
THE HIGH PLAINS OF WESTERN NEBRASKA AND EASTERN COLORADO...THE
COLD FRONT WILL HAVE LITTLE IMPACT...WITH A PACIFIC AIRMASS AND
HIGHS IN THE 40S REMAINING IN PLACE.
BY MID TO LATE WEEK...UPPER LEVEL RIDGING WILL BUILD EAST ACROSS
THE CENTRAL CONUS. WARMER PACIFIC AIR WILL ALSO SPREAD EAST...WITH
HIGHS IN THE UPPER 30S TO MID 40S REGION WIDE. LITTLE
PRECIPITATION IS EXPECTED...AS ATMOSPHERIC MOISTURE REMAINS
LIMITED THROUGH THE END OF THE WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1225 PM CST SUN NOV 24 2013
WINDS WILL BE BREEZY FROM THE SOUTH-SOUTHWEST THROUGH THE
AFTERNOON. WINDS WILL DIMINISH BY 00Z...THEN WILL SWITCH TO THE
NORTHWEST OVERNIGHT AS A WEAK FRONT MOVES ACROSS WESTERN
NEBRASKA. LOOK FOR THE WINDS TO INCREASE THEN BY LATE MONDAY
MORNING...WHERE GUSTS COULD REACH 20KTS INTO THE AFTERNOON. THERE
CONTINUES TO BE INDICATION OF STRATUS DEVELOPMENT INTO SOUTHWEST
NEBRASKA TONIGHT /PRIMARILY IMPACTING KLBF/ AS MODELS ARE SHOWING A
SHALLOW LAYER OF MOISTURE IN THE BOUNDARY LAYER MOVING INTO THE
AREA. THE MODELS HAVE BEEN HAVING SOME PROBLEMS HANDLING THIS LOW
LEVEL MOISTURE OVER THE LAST SEVERAL DAYS SO DON/T HAVE MUCH
CONFIDENCE IN THAT SOLUTION AND LEFT THE MVFR CEILINGS OUT OF THE
FORECAST FOR NOW. WILL KEEP A WATCH ON THIS THROUGH THE AFTERNOON.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...BROOKS
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
1105 AM PST SUN NOV 24 2013
.SYNOPSIS...A SLOW MOVING LOW PRESSURE WILL FINALLY PULL AWAY FROM
THE AREA TODAY RESULTING IN DRIER CONDITIONS. FURTHER WARMING IS
EXPECTED ACROSS THE AREA MONDAY THROUGH WEDNESDAY. ANOTHER AREA OF
LOW PRESSURE DROPPING SOUTH NEAR THE CALIFORNIA COAST MAY BRING A
FEW SHOWERS MAINLY TO WESTERN PORTIONS OF THE AREA FOR THANKSGIVING
DAY AND FRIDAY.
&&
.UPDATE...UPPER LOW EXITING THE REGION TODAY WITH A FEW SHOWERS
STILL POSSIBLE IN MOHAVE COUNTY AND FAR EASTERN LINCOLN COUNTY.
CLOUDS HAD CLEARED OUT A BIT MORE THAN PREVIOUSLY FORECAST AND THE
SKY COVER GRID WAS ADJUSTED TO REDUCE SKY COVER OVER A GOOD PORTION
OF THE FORECAST AREA. NO OTHER UPDATES NEEDED.
&&
.AVIATION...FOR MCCARRAN...SOME DRYING OF THE LOWER LEVELS OF THE
ATMOSPHERE IS TAKING PLACE...AND THE LOWEST CLOUD BASES HAVE
SCATTERED OUT LEAVING CIGS GENERALLY AROUND 10K FEET. CLEARING
BEGINS TONIGHT WITH MAINLY CLEAR SKIES EXPECTED MONDAY. WINDS WILL
FAVOR MORE TYPICAL DIURNAL TRENDS THROUGH TONIGHT AT SPEEDS MAINLY
LESS THAN 6 KTS.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...SHOWERS SHOULD BE CONFINED TO EASTERN MOHAVE COUNTY
THROUGH AROUND 21Z. CIGS BTWN 5K-8K FEET IN THIS AREA OTHERWISE
SCT-BKN AROUND 10K FEET. WINDS OVERALL SHOULD FAVOR TYPICAL DIURNAL
TRENDS AT 10 KTS OR LESS. MAINLY CLEAR CONDITIONS MONDAY EXPECT FOR
PATCHY FG/BR POSSIBLE EARLY IN THE MORNING.
&&
.PREV DISCUSSION...
254 AM PST SUN NOV 24 2013
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT.
WELL AFTER 3 DAYS OF CLOUDS AND RAIN WE ARE FINALLY IN FOR A CHANGE
TODAY IN VEGAS WITH THE POTENTIAL OF SEEING SOME SUNSHINE AS A SLOW
MOVING UPPER LEVEL LOW FINALLY HEADS OUT OF THE AREA. THE LATEST
WATER VAPOR IMAGERY SHOWS THE CENTER OF THE LOW NEAR PARKER, ARIZONA
AS OF EARLY THIS MORNING WITH MOISTURE STILL WRAPPING AROUND THE
BACK SIDE OF THE LOW. THE MAIN ISSUE FOR TODAY, ESPECIALLY FOR THIS
MORNING, WILL BE HOW QUICKLY WE ARE ABLE TO DRY THINGS OUT ACROSS
THE AREA WHICH WILL DETERMINE WHEN SHOWERS COME TO AN END AND HOW
QUICKLY ANY LOW AND MID-LEVEL CLOUDS START TO BECOME MORE SCATTERED.
THE LATEST RADAR IMAGES FROM KESX SHOW MAINLY LIGHT RETURNS ACROSS
THE EASTERN PORTIONS OF THE AREA AND IT IS LIKELY THE RADAR IS
OVERSHOOTING SOME OF THE PRECIPITATION. BASED ON THE HRRR AND THE
00Z REGIONAL WRF, THE BEST POTENTIAL FOR ANY SHOWERS THIS MORNING
WILL BE ACROSS NORTHERN AND CENTRAL MOHAVE COUNTY, LINCOLN COUNTY
AND THE MOUNTAINS OF CLARK COUNTY AND I HAVE KEPT IN 20-30 POPS WITH
SOME NEAR 40 POP VALUES (IN THE HIGHEST TERRAIN) OVER THESE AREAS.
AS THE LOW LEVELS START TO DRY OUT, WE SHOULD SEE THE LOWER AND
MID-LEVEL CLOUDS START TO BECOME MORE SCATTERED IN COVERAGE BY EARLY
THIS AFTERNOON ESPECIALLY FROM LINCOLN AND CLARK COUNTIES ON EAST.
THERE COULD BE A LITTLE FOG AROUND, MAINLY ALONG THE INTERFACES OF
THE HIGHER TERRAIN WHERE THEY HIT THE CLOUD BASES. OUTSIDE OF THE
COLORADO CITY AREA WHERE FOG WAS REPORTED EARLIER THIS MORNING, NO
OTHER FOG WILL BE PLACED IN THE GRIDS AS THE COVERAGE LOOKS TOO
SMALL. WITH THE COLD POOL DEPARTING THE AREA ASSOCIATED WITH THE
LOW, A LOT OF WARMING ALOFT WILL TAKE PLACE TODAY. THIS COMBINED
WITH SOME SUN WILL MAKE FOR A BIG BOOST IN TEMPS, HOWEVER, HIGHS
SHOULD STILL BE ABOUT 10 DEGREES BELOW NORMAL ACROSS THE AREA AND I
DID CHOP A FEW DEGREES OFF THE PREVIOUS FORECAST BASED ON THE LATEST
GUIDANCE.
FOR TONIGHT, SOME LOW AND MID-LEVEL CLOUDS MAY LINGER EARLY ON,
OTHERWISE EXPECT A CLEAR SKY. TEMPS SHOULD BE A LITTLE COLDER WITH
LESS CLOUD COVER. ONE CONCERN WILL BE IN THE WESTERN PORTIONS OF THE
MOJAVE DESERT, MAINLY ACROSS NW SAN BERNARDINO COUNTY AND FAR SW
INYO COUNTY, WHERE PATCHY FOG MAY BE POSSIBLE. STATISTICAL GUIDANCE
SHOWS NEARLY SATURATED OR SATURATED SFC CONDITIONS TONIGHT
(ESPECIALLY THE COLDER MET GUIDANCE) AND BUFKIT SOUNDINGS FROM THE
NAM SHOW THE VERY LOW-LEVELS MOISTENING AROUND OR JUST AFTER
SUNRISE. I WILL GO AHEAD AND ADD PATCHY FOG IN HERE GIVEN THE WET
GROUND FROM THE RECENT RAINS, LIGHT WINDS AND CLEAR SKY EXPECTED
INITIALLY TONIGHT, HOWEVER CONFIDENCE IS NOT THE BEST WITH THIS.
RIDGING ALOFT IS FORECAST TO SLIDE EAST ACROSS THE AREA FROM MONDAY
INTO TUESDAY. THIS WILL RESULT IN FURTHER WARMING WITH HIGHS ABOUT
4-6 DEGREES BELOW NORMAL. AS THE RIDGE AXIS SLIDES EAST ON TUESDAY
AND A TROUGH OFFSHORE STARTS TO APPROACH HIGH LEVEL MOISTURE SHOULD
START TO SPILL IN FROM THE WEST AND COULD BRING A DECENT AMOUNT OF
CIRRUS TO THE AREA FOR TUESDAY NIGHT.
.LONG TERM...WEDNESDAY THROUGH SATURDAY...THE PACIFIC SYSTEM THAT IS
FORECAST TO APPROACH THE WEST COAST BY LATE WEDNESDAY DOES NOT
APPEAR TO HAVE THE MAKINGS OF A SIGNIFICANT STORM FOR OUR FORECAST
AREA. THE LATEST MEDIUM RANGE MODELS ARE NOW IN BETTER AGREEMENT
WITH THE TRACK OF THE SYSTEM....BRINGING THE CENTER OF THE CLOSED
LOW ALONG THE CENTRAL CALIFORNIA COAST THANKSGIVING DAY THEN
INDICATING IT WILL TRANSFORM INTO A WEAKER AND ELONGATED POSITIVE
TILT TROUGH AS IT SAGS OFF THE SOUTHERN CALIFORNIA COAST FRIDAY AND
CONTINUES WORKING TOWARD NORTHERN BAJA SATURDAY. THE BEST CHANCE FOR
PRECIPITATION WILL BE ACROSS THE SOUTHERN SIERRA AND THE INYO COUNTY
MOUNTAINS THANKSGIVING DAY INTO THURSDAY NIGHT AS A SHORTWAVE EJECTS
OUT OF THE COASTAL LOW ACROSS SOUTHEAST CALIFORNIA AND SOUTHERN
NEVADA. SNOW WILL BE LIKELY IN THE HIGH SIERRA WITH LESSER CHANCES
FOR LIGHT SNOW SHOWERS ACROSS THE REST OF THE INYO COUNTY MOUNTAINS
AND THE MOUNTAINS OF SOUTHERN NEVADA. PRECIPITATION CHANCES THEN
DIMINISH CONSIDERABLY FRIDAY INTO SATURDAY. CONSIDERING THE SEED FOR
THIS SYSTEM IS CURRENTLY A BARELY NOTICEABLE PACIFIC SHORTWAVE NEAR
40N AND THE DATELINE...THERE ARE SURE TO BE SOME CHANGES DURING ITS
EVOLUTION. IT BEARS WATCHING BUT DOES NOT LOOK THAT IMPRESSIVE FOR
NOW.
&&
.CLIMATE...WE HAVE HAD OUR FILL OF CLOUDS IN THE SKY HERE IN VEGAS
THE LAST FEW DAYS BUT WHEN IS THE LAST TIME WE HAD 3 DAYS WITH THIS
MUCH CLOUD COVER AROUND? BASED ON SUNRISE TO SUNSET CLOUD COVER, THE
LAST TIME WE HAD BACK-TO-BACK DAYS WITH A 10 (WHICH MEANS AS CLOUDY
AS IT GETS) WAS ON DECEMBER 20TH AND 21ST OF 2010. THOSE AROUND THEN
HERE WILL REMEMBER THAT AS A PERIOD WHEN A BARRAGE OF STORMS CAME IN
FROM THE PACIFIC. THIS WAS ALSO THE ONLY SUCH PERIOD LOOKING BACK
THROUGH SKY COVER RECORDS FOR THE LAST 5 YEARS TO NOVEMBER 2008.
&&
.VEF WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
AZ...NONE.
CA...NONE.
&&
$$
UPDATE...HARRISON
AVIATION...SALMEN
PREV DISCUSSION...STACHELSKI/ADAIR
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
211 PM EST SUN NOV 24 2013
.SYNOPSIS...
THE NORTH COUNTRY WILL REMAIN UNDER COLD NORTHWESTERLY FLOW FOR
TODAY AND TONIGHT...AS LOW PRESSURE REMAINS TO OUR EAST AND HIGH
PRESSURE OFF TO OUR WEST. THAT AREA OF HIGH PRESSURE WILL SHIFT
EAST OVER THE REGION LATER TONIGHT...FOLLOWED BY ANOTHER LOW FOR
MONDAY AFTERNOON INTO TUESDAY. THERE IS THE POTENTIAL FOR A WINTER
STORM TO AFFECT THE REGION STARTING LATE TUESDAY NIGHT AND INTO
WEDNESDAY NIGHT. HIGH PRESSURE SLOWLY RETURNS FOR THURSDAY INTO
FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 931 AM EST SUNDAY...HAVE UPDATED THE FORECAST TO RAISE POPS
ACROSS MUCH OF NC/NE VT THROUGH THE DAY...AND TO INTRODUCE AREAS
OF BLOWING SNOW IN THESE AREAS. ALSO LOWERED HOURLY AND MAX
TEMPERATURES BY A FEW DEGREES BASED OFF CURRENT OBSERVATIONAL DATA
AND LATEST LAMP GUIDANCE NUMBERS. COLD DAY ON TAP WITH STRONG AND
GUSTY NORTHWESTERLY FLOW CONTINUING. THUS WIND ADVISORIES REMAIN
IN PLACE...ESP ACROSS THE HIGHER TERRAIN AND DOWNSLOPE LOCATIONS
ALONG THE EASTERN SLOPES OF THE DACKS/GREENS. STRONGEST GUSTS
LIKELY THIS AFTERNOON WHEN SECONDARY PRESSURE SURGE PUSHES SOUTH
INTO THE REGION. GUSTS IN ADVISORY LOCATIONS IN THE 35 TO 45 MPH
RANGE WITH LOCALLY HIGHER GUSTS...SLIGHTLY LESS ELSEWHERE. WHILE
MOISTURE CONTINUES TO SLOWLY THIN...LINGERING WRAP- AROUND
OROGRAPHICALLY ENHANCED SHSN CONTINUE ACROSS THE NRN MTNS WHERE
SOME MINOR ADDITIONAL ACCUMULATIONS WILL BE POSSIBLE TODAY. THIS
IS IN CLOSE AGREEMENT WITH LATEST 12/13Z RAP PROGS WHICH HAVE A
GOOD HANDLE ON THE CURRENT SITUATION. THUS WILL LEAN IN ITS
DIRECTION ACCORDINGLY. WITH DEEPLY MIXED PBL...FROUDE NUMBERS
QUITE HIGH SO BEST COVERAGE OF SHSN/ACCUMS FROM THE GREEN MTN
SPINE EASTWARD. TEMPERATURES REALLY GOING NOWHERE WITH SUCH STRONG
CAA IN PLACE...SO READINGS HOLDING MORE OR LESS STEADY...PERHAPS
CLIMBING A DEGREE OR TWO WILL BE ALL WE GET TODAY. WITH THE
AFORMENTIONED WINDS THE APPARENT TEMPS SHOULD RANGE IN THE -10F TO
+5F RANGE...COLDER TO NEAR -20F AT THE SUMMITS. DEFINITELY A DAY
TO WEAR THE FULL WINTER CLOTHING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
AS OF 352 AM EST SUNDAY...TONIGHT WITH RIDGE APPROACHING AND WINDS
ABATING...TEMPS WILL DROP SHARPLY TO LOWEST OF THE SEASON SO FAR
WITH LOWS RANGING FROM -5 TO 10F IN DACKS TO SINGLE NUMBERS
ELSEWHERE. WIND ADVISORY REMAINS IN AFFECT THRU TNGT AS TIGHT
GRADIENT CREATING STEADY 15-30 MPH WINDS WITH GUSTS
40-50MPH...HIGHEST OVER DACKS AND E VT. BY 00Z MONDAY...GRADIENT
WILL SLACKEN AND TAPER OFF BY MIDNGT WITH ARRIVAL OF SFC RIDGE.
WIND CHILL ISSUES POSSIBLE IN RANGE OF 0F TO -10F.
COLD CHILLY MORNING ON MONDAY W/ RIDGE CRESTING OVER THE AREA AND
SLIDING S AND E DURING THE DAY. THIS WILL ALLOW WAA ON SSW FLOW TO
SETUP OVER THE AREA...AND PROVIDE A NICE REBOUND IN TEMPS FROM THE
COLD WEEKEND. WAA WILL BRING HIGHS MONDAY INTO THE 20S FOR ALL
SITES. INCR CLDS THOUGH OVER N NY AS NORTHERN STREAM SYSTEM COMES
OUT OF THE GREAT LKS REGION AND INTO QUEBEC MON AFTNOON/TUESDAY
MORNING. BLOCKING RIDGE TO OUR SOUTH WILL PUT BEST POP FOCUS OVER
N NY TAPERING DOWN TO SE VT. ADDITIONAL LIGHT SNOWFALL WILL OCCUR
BRINGING AROUND AN INCH OF NEW SNOW TAPERING OFF TO A POTENTIAL
DUSTING IN SOUTHERN ZONES. CLD COVER KEEPS TEMPS FROM DROPPING TOO
MUCH ALONG WITH GRADIENT STAYING SW. LOOKING FOR LOWS IN THE TEENS
TO L20S. GOING INTO TUESDAY SW GRADIENT STAYS INTACT FOR THE DAY
AS NORTHERN SYSTEM...THAT COULD BRING STORM NEAR
THANKSGIVING...SWINGS THRU THE GREAT LKS. CLDS/MOISTURE FEED WILL
ALLOW FOR SL CHANCE OF -SW WITH FOCUS OVER SOUTHERN ZONES. OVERALL
INCH OR LESS EXPECTED...WITH HIGHS IN THE 30S.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 209 PM EST SUNDAY...INALLY SOME CONSENSUS IN ALL MAJOR
MODELS WITH THE 12Z GFS BEING THE LATECOMER TO THE PARTY FOR THIS
MID WEEK...HOLIDAY TRAVEL STORM.
THE SHORT TERM DISCUSSION TOUCHES UPON ALOT OF THE EVOLVING SYSTEM
BUT THE CURRENT WED FCST IS BASED ON A GFS/ECMWF/NAM TRACK OF
NYC-ORH-CON. CNDN GEM IS MORE HUDSON/CHAMPLAIN VLY BUT ERRING TO A
SLIGHTLY COLDER...MORE PROBLEMATIC SOLUTION.
IN GENERAL...A SNOW/MIXED START WITH GRADUAL CHANGEOVER TO
MIXED/RAIN IN VT AND CHMPL VLY NY WITH SOME POSSIBLE ACCUMULATING
SNOW AND A FLASH FREEZE MARCHING FROM WEST TO EAST AFT SFC LOW
PASSAGE WED EVE/WED NGT. ADRNDKS/ST LWRNC VLY IN THE POTENTIAL
SWEET-SPOT FOR HEAVY SNOWFALL ALONG WITH SOME MIXING.
QPF AMOUNTS OF 1-2 INCHES ACROSS MUCH OF THE FA...LIGHTER SIDE ACRS
ST LWRNC VLY WHERE IT WILL STAY COLDEST. WPC WINTER WX GRAPHIC
PLACES 6-12 INCHES IN ADRNDKS/ST LWRNC VLY AND QUITE POSSIBLE. LLVL
NNE JET ACRS ST LWRNV VLY WILL ADD PROBLEMS WITH CONSIDERABLE
BLOWING SNOW.
LLVL TEMP PROFILES AND SHARP GRADIENT LEADS TO CONCERNS OF ICING IN
INTERIOR VT AND CT RVR VLY DUE TO STG INVERSIONS. IN ADDITION...A
NNE LLVL FLOW IN ST LWRNC VLY THAT MAY ADVECT LLVL COLD AIR TOWARD
NRN CHAMPL VLY FOR A WINTRY MIX.
AGAIN...LATE WED/WED NGT AS SFC LOW DEPARTS STG CAA AND WRAPARD PCPN
CHANGING TO SNOW AND FALLING TMPS WILL LIKELY RESULT IN A FLASH
FREEZE SITUATION ON ROADS...TREES AND UTILITY LINES AND WITH NNW
WINDS INCREASING TO 20-30KTS PSBLY BLOWING SNOW AND POWER OUTAGES.
THANKSGIVING...BLUSTERY AND LEFTOVER MTN SNOW SHOWERS BUT COLD
THROUGHOUT THE DAY.
THEREAFTER...CONTINUED BELOW NORMAL TEMPERATURES (10-15 DEGS BLO)
CONTINUE THROUGH THE WEEKEND WITH REINFORCING SHOTS OF COLD AIR AND
CHC OF FLURRIES.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
THROUGH 18Z MONDAY...STRONG W-NW WINDS WILL CONTINUE INTO THIS
EVENING. SNOW SHOWER ACTIVITY IS GRADUALLY DECREASING WITH DRIER
AIR MOVING IN...BUT PERIODS OF IFR AT KMPV DUE TO BLOWING SNOW.
ELSEWHERE...VFR WITH CLRG SKIES BY AND DURING THE EVENING.
KBTV/KMPV WILL SEE WNW WINDS 20G35KTS THRU 00Z MON...ELSEWHERE
WILL BE 15-18G28KTS ALL DIMINISHING AFT 04Z.
OUTLOOK 18Z MONDAY THROUGH THURSDAY...DRY AND MOSTLY CLEAR VFR WITH
HIGH PRESSURE IN PLACE MONDAY. THERE WILL BE A CHANCE FOR MVFR
CIGS/VIS IN SNOW SHOWERS MONDAY NIGHT AND TUESDAY AS WEAK UPPER
LEVEL TROUGH MOVES ACROSS THE NORTH COUNTRY. MODERATE TO HIGH PREDICTABILITY
FOR WEDNESDAY WITH INCREASING CONFIDENCE OF STORM TRACK WITHIN 50
MILES OF A KLGA-KBDL-KORH-KCON LINE. POSSIBILITY EXISTS FOR IFR
CONDITIONS WITH ACCUMULATING SNOWFALL AND MIXED WEDNESDAY BUT DETAILS
ARE UNCERTAIN. THURSDAY...MODERATE N-NW WINDS WITH ISOLD -SHSN
POSSIBLE...MAINLY VCNTY MTNS. TAF LOCATIONS SHOULD BE MAINLY VFR
FOR THURSDAY.
&&
.MARINE...
AS OF 352 AM EST SUNDAY...A LAKE WIND ADVISORY REMAINS IN EFFECT
AND WILL LIKELY REMAIN SO THROUGH TONIGHT. WINDS NORTHWEST 20 TO
30 KNOTS...TAPERING TO 15 TO 25 KNOTS TONIGHT. WAVES WILL BUILD TO
3-5 FEET IMPACTING NORTH-FACING EXPOSURES.
&&
.CLIMATE...
THE COLD TEMPERATURES SUNDAY 11/24 INTO MONDAY 11/25 MAY APPROACH
RECORD LEVELS. THE RECORDS ARE LISTED BELOW:
RECORD LOW AND RECORD LOW MAXIMUMS SUNDAY 11/24:
BURLINGTON (BTV)- 2 (1956), 19 (1938)
MONTPELIER (MPV)- -4 (1989), 20 (2000)
MASSENA (MSS)- -8 (2000), 19 (1996)
SAINT JOHNSBURY (SJBV1)- -6 (1989), 20 (1921)
RECORD LOW AND RECORD LOW MAXIMUMS MONDAY 11/25:
BURLINGTON (BTV)- -1 (1938), 14 (1938)
MONTPELIER (MPV)- 4 (1997,1993), 24 (1993,1971)
MASSENA (MSS)- 5 (2005), 23 (1993)
SAINT JOHNSBURY (SJBV1)- 0 (1956), 19 (1938)
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR VTZ003-004-
006>008-010-012-016>019.
NY...WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR NYZ028-031-034-
035.
&&
$$
SYNOPSIS...JN
NEAR TERM...JMG
SHORT TERM...JN
LONG TERM...SLW
AVIATION...BANACOS/SLW
MARINE...LOCONTO
CLIMATE...MUCCILLI
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1232 PM EST SUN NOV 24 2013
.SYNOPSIS...
THE NORTH COUNTRY WILL REMAIN UNDER COLD NORTHWESTERLY FLOW FOR
TODAY AND TONIGHT...AS LOW PRESSURE REMAINS TO OUR EAST AND HIGH
PRESSURE OFF TO OUR WEST. THAT AREA OF HIGH PRESSURE WILL SHIFT
EAST OVER THE REGION LATER TONIGHT...FOLLOWED BY ANOTHER LOW FOR
MONDAY AFTERNOON INTO TUESDAY. THERE IS THE POTENTIAL FOR A WINTER
STORM TO AFFECT THE REGION STARTING LATE TUESDAY NIGHT AND INTO
WEDNESDAY NIGHT. HIGH PRESSURE SLOWLY RETURNS FOR THURSDAY INTO
FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 931 AM EST SUNDAY...HAVE UPDATED THE FORECAST TO RAISE POPS
ACROSS MUCH OF NC/NE VT THROUGH THE DAY...AND TO INTRODUCE AREAS
OF BLOWING SNOW IN THESE AREAS. ALSO LOWERED HOURLY AND MAX
TEMPERATURES BY A FEW DEGREES BASED OFF CURRENT OBSERVATIONAL DATA
AND LATEST LAMP GUIDANCE NUMBERS. COLD DAY ON TAP WITH STRONG AND
GUSTY NORTHWESTERLY FLOW CONTINUING. THUS WIND ADVISORIES REMAIN
IN PLACE...ESP ACROSS THE HIGHER TERRAIN AND DOWNSLOPE LOCATIONS
ALONG THE EASTERN SLOPES OF THE DACKS/GREENS. STRONGEST GUSTS
LIKELY THIS AFTERNOON WHEN SECONDARY PRESSURE SURGE PUSHES SOUTH
INTO THE REGION. GUSTS IN ADVISORY LOCATIONS IN THE 35 TO 45 MPH
RANGE WITH LOCALLY HIGHER GUSTS...SLIGHTLY LESS ELSEWHERE. WHILE
MOISTURE CONTINUES TO SLOWLY THIN...LINGERING WRAP- AROUND
OROGRAPHICALLY ENHANCED SHSN CONTINUE ACROSS THE NRN MTNS WHERE
SOME MINOR ADDITIONAL ACCUMULATIONS WILL BE POSSIBLE TODAY. THIS
IS IN CLOSE AGREEMENT WITH LATEST 12/13Z RAP PROGS WHICH HAVE A
GOOD HANDLE ON THE CURRENT SITUATION. THUS WILL LEAN IN ITS
DIRECTION ACCORDINGLY. WITH DEEPLY MIXED PBL...FROUDE NUMBERS
QUITE HIGH SO BEST COVERAGE OF SHSN/ACCUMS FROM THE GREEN MTN
SPINE EASTWARD. TEMPERATURES REALLY GOING NOWHERE WITH SUCH STRONG
CAA IN PLACE...SO READINGS HOLDING MORE OR LESS STEADY...PERHAPS
CLIMBING A DEGREE OR TWO WILL BE ALL WE GET TODAY. WITH THE
AFORMENTIONED WINDS THE APPARENT TEMPS SHOULD RANGE IN THE -10F TO
+5F RANGE...COLDER TO NEAR -20F AT THE SUMMITS. DEFINITELY A DAY
TO WEAR THE FULL WINTER CLOTHING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
AS OF 352 AM EST SUNDAY...TONIGHT WITH RIDGE APPROACHING AND WINDS
ABATING...TEMPS WILL DROP SHARPLY TO LOWEST OF THE SEASON SO FAR
WITH LOWS RANGING FROM -5 TO 10F IN DACKS TO SINGLE NUMBERS
ELSEWHERE. WIND ADVISORY REMAINS IN AFFECT THRU TNGT AS TIGHT
GRADIENT CREATING STEADY 15-30 MPH WINDS WITH GUSTS
40-50MPH...HIGHEST OVER DACKS AND E VT. BY 00Z MONDAY...GRADIENT
WILL SLACKEN AND TAPER OFF BY MIDNGT WITH ARRIVAL OF SFC RIDGE.
WIND CHILL ISSUES POSSIBLE IN RANGE OF 0F TO -10F.
COLD CHILLY MORNING ON MONDAY W/ RIDGE CRESTING OVER THE AREA AND
SLIDING S AND E DURING THE DAY. THIS WILL ALLOW WAA ON SSW FLOW TO
SETUP OVER THE AREA...AND PROVIDE A NICE REBOUND IN TEMPS FROM THE
COLD WEEKEND. WAA WILL BRING HIGHS MONDAY INTO THE 20S FOR ALL
SITES. INCR CLDS THOUGH OVER N NY AS NORTHERN STREAM SYSTEM COMES
OUT OF THE GREAT LKS REGION AND INTO QUEBEC MON AFTNOON/TUESDAY
MORNING. BLOCKING RIDGE TO OUR SOUTH WILL PUT BEST POP FOCUS OVER
N NY TAPERING DOWN TO SE VT. ADDITIONAL LIGHT SNOWFALL WILL OCCUR
BRINGING AROUND AN INCH OF NEW SNOW TAPERING OFF TO A POTENTIAL
DUSTING IN SOUTHERN ZONES. CLD COVER KEEPS TEMPS FROM DROPPING TOO
MUCH ALONG WITH GRADIENT STAYING SW. LOOKING FOR LOWS IN THE TEENS
TO L20S. GOING INTO TUESDAY SW GRADIENT STAYS INTACT FOR THE DAY
AS NORTHERN SYSTEM...THAT COULD BRING STORM NEAR
THANKSGIVING...SWINGS THRU THE GREAT LKS. CLDS/MOISTURE FEED WILL
ALLOW FOR SL CHANCE OF -SW WITH FOCUS OVER SOUTHERN ZONES. OVERALL
INCH OR LESS EXPECTED...WITH HIGHS IN THE 30S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 640 AM EST SUNDAY...STILL CONSIDERABLE MODEL DIFFERENCES
CONCERNING MOISTURE-LADEN SYNOPTIC LOW EXPECTED TO AFFECT THE
NORTH COUNTRY TUESDAY NIGHT INTO WEDNESDAY...WHICH UNFORTUNATELY
COINCIDES WITH ONE OF THE BUSIEST TRAVEL DAYS OF THE YEAR. THE 00Z
NWP DIFFERENCES CONTINUE TO SURROUND INTERACTION BETWEEN VIGOROUS
BUT DISTINCT NRN AND SRN STREAM SHORTWAVE TROUGHS AS SYSTEMS CROSS
THE OHIO VALLEY AND SERN STATES...RESPECTIVELY. THE DEEPER AND
MORE PHASED SOLN OFFERED BY THE 00Z ECMWF TAKES THE LOW INLAND UP
THE EAST COAST AND ULTIMATELY TRACKS A 986MB LOW ACROSS VT BETWEEN
18Z WED AND 00Z THU. THIS IS A WARMER SOLN WITH 850MB TEMPS
REACHING +8C ACROSS VT AT 18Z WEDNESDAY. ANY SNOW AT THE ONSET TUESDAY
NIGHT WOULD SWITCH OVER TO MAINLY RAIN ACROSS THE REGION.
MEANWHILE...THE 00Z GFS CONTINUES THAT MODEL/S TENDENCY TO KEEP A
FASTER MOVING SYSTEM OFFSHORE BETWEEN THE 40N 70W BENCHMARK AND
CAPE COD WITH A 994MB LOW MOVING THROUGH AT 18Z WEDNESDAY. THIS IS
A MUCH COLDER SOLN...WITH POTENTIAL ACCUMULATING SNOW ACROSS VT
AND LESS PRECIPITATION IMPACT FOR NRN NY. HAVE INCREASED POPS TO
70-80 PERCENT LATE TUESDAY THROUGH WEDNESDAY ASSOCIATED WITH THIS
SYSTEM WITH QPF ON THE ORDER OF 1"...BUT IT REMAINS TOO SOON TO
DETERMINE P-TYPE DETAILS GIVEN UNCERTAIN EVOLUTION/PHASING OF NRN
AND SRN STREAMS. THOSE WITH TRAVEL PLANS WEDNESDAY SHOULD CONSIDER
PROSPECT FOR WINTER TRAVEL CONDITIONS ACROSS THE NORTH
COUNTRY...BUT THAT IS BY NO MEANS A SURE THING AT THIS POINT.
WE/LL MAINTAIN MENTION OF THIS SYSTEM IN THE HAZARDOUS WEATHER
OUTLOOK.
CONDITIONS WILL TREND COLDER AND DRIER FOR THANKSGIVING DAY AS
SYNOPTIC LOW DEPARTS NEWD THRU QUEBEC/CANADIAN MARITIMES. NWLY
WINDS AT 10-20 MPH WITH A FEW FLURRIES IN THE NRN GREENS INTO NERN
VT. LOWS WEDNESDAY NIGHT WILL BE IN THE UPR TEENS TO LOWER
20S...FOLLOWED BY HIGHS MAINLY IN THE 20S FOR THANKSGIVING DAY.
HIGH PRESSURE SHOULD BRING DRY AND SEASONABLY COLD CONDITIONS
FRIDAY AND SATURDAY. HIGH TEMPS GENERALLY REMAIN IN THE 20S THRU
THE END OF THE FORECAST PERIOD SATURDAY.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
THROUGH 18Z MONDAY...STRONG W-NW WINDS WILL CONTINUE INTO THIS
EVENING. SNOW SHOWER ACTIVITY IS GRADUALLY DECREASING WITH DRIER
AIR MOVING IN...BUT PERIODS OF IFR AT KMPV DUE TO BLOWING SNOW.
ELSEWHERE...VFR WITH CLRG SKIES BY AND DURING THE EVENING.
KBTV/KMPV WILL SEE WNW WINDS 20G35KTS THRU 00Z MON...ELSEWHERE
WILL BE 15-18G28KTS ALL DIMINISHING AFT 04Z.
OUTLOOK 18Z MONDAY THROUGH THURSDAY...DRY AND MOSTLY CLEAR VFR WITH
HIGH PRESSURE IN PLACE MONDAY. THERE WILL BE A CHANCE FOR MVFR
CIGS/VIS IN SNOW SHOWERS MONDAY NIGHT AND TUESDAY AS WEAK UPPER
LEVEL TROUGH MOVES ACROSS THE NORTH COUNTRY. MODERATE TO HIGH PREDICTABILITY
FOR WEDNESDAY WITH INCREASING CONFIDENCE OF STORM TRACK WITHIN 50
MILES OF A KLGA-KBDL-KORH-KCON LINE. POSSIBILITY EXISTS FOR IFR
CONDITIONS WITH ACCUMULATING SNOWFALL AND MIXED WEDNESDAY BUT DETAILS
ARE UNCERTAIN. THURSDAY...MODERATE N-NW WINDS WITH ISOLD -SHSN
POSSIBLE...MAINLY VCNTY MTNS. TAF LOCATIONS SHOULD BE MAINLY VFR
FOR THURSDAY.
&&
.MARINE...
AS OF 352 AM EST SUNDAY...A LAKE WIND ADVISORY REMAINS IN EFFECT
AND WILL LIKELY REMAIN SO THROUGH TONIGHT. WINDS NORTHWEST 20 TO
30 KNOTS...TAPERING TO 15 TO 25 KNOTS TONIGHT. WAVES WILL BUILD TO
3-5 FEET IMPACTING NORTH-FACING EXPOSURES.
&&
.CLIMATE...
THE COLD TEMPERATURES SUNDAY 11/24 INTO MONDAY 11/25 MAY APPROACH
RECORD LEVELS. THE RECORDS ARE LISTED BELOW:
RECORD LOW AND RECORD LOW MAXIMUMS SUNDAY 11/24:
BURLINGTON (BTV)- 2 (1956), 19 (1938)
MONTPELIER (MPV)- -4 (1989), 20 (2000)
MASSENA (MSS)- -8 (2000), 19 (1996)
SAINT JOHNSBURY (SJBV1)- -6 (1989), 20 (1921)
RECORD LOW AND RECORD LOW MAXIMUMS MONDAY 11/25:
BURLINGTON (BTV)- -1 (1938), 14 (1938)
MONTPELIER (MPV)- 4 (1997,1993), 24 (1993,1971)
MASSENA (MSS)- 5 (2005), 23 (1993)
SAINT JOHNSBURY (SJBV1)- 0 (1956), 19 (1938)
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR VTZ003-004-
006>008-010-012-016>019.
NY...WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR NYZ028-031-034-
035.
&&
$$
SYNOPSIS...JN
NEAR TERM...JMG
SHORT TERM...JN
LONG TERM...BANACOS
AVIATION...BANACOS/SLW
MARINE...LOCONTO
CLIMATE...MUCCILLI
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1235 PM CST SUN NOV 24 2013
.DISCUSSION...
18Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
AN APPROACHING WEAK SHORTWAVE DISTURBANCE IS THE IMPETUS TO A
LIGHT RAIN SHIELD THAT WILL BE AFFECTING THE MORE NORTHERN TERMINALS
THROUGH 21Z THIS AFTERNOON. VFR OVERCAST THROUGH THE AFTERNOON...
LOWERING CEILINGS THIS EVENING INTO MVFR CAT/BORDERLINE IFR FROM
25/09Z INTO SUNRISE. NORTHERN COUNTY MODEL PROFILES ARE TRENDING
WARMER...WITH A THIN FREEZING OFF-THE-SURFACE LAYER EARLY MONDAY
MORNING. THUS...NO MENTION OF FROZEN PRECIP MIX IN KCLL AND KUTS
TAFS AT THIS TIME. A BROAD UPPER LOW OVER ARIZONA WILL ADVANCE
INTO THE TEXAS PANHANDLE OVER THE NEXT 24 HOURS. AHEAD OF THIS
FEATURE...A DEVELOPING CENTRAL TEXAS SURFACE TROUGH WITH WARMER
MOIST MID-LEVEL AIR OVERUNNING COOLER SFC AIR WILL AID IN INITIATING
NORTH-TO-SOUTH RAINFALL AS EARLY AS THE PRE-DAWN HOURS. MID-LATE
MONDAY MORNING INTO EARLY AFTERNOON IS TIMED TO BE WHEN MANY HUBS
EXPERIENCE HIGH IFR/LOW MVFR CONDITIONS WITHIN HEAVIER RAIN EPISODES.
31
&&
.PREV DISCUSSION... /ISSUED 1118 AM CST SUN NOV 24 2013/
UPDATE...
SEE MORNING UPDATE.
DISCUSSION...
12Z UPPER AIR DATA SHOWS GREATER SATURATION AT 850 MB AND 700 MB
THAT YESTERDAY. A WELL DEFINED S/WV IS ALSO NOTED AT BOTH 850 MB
AND 700 MB. THE RAP 13 SHOWS AN AREA OF PRECIP MOVING INTO THE
REGION THIS AFTN INTO THIS EVENING BUT THERE IS LAYER OF VERY DRY
AIR NEAR THE SURFACE THAT WILL NEED TO BE OVERCOME. THINK CHANCE
POPS ARE THE WAY TO GO AND WILL TAPER HIGHER POPS WEST AND LOWER
POPS EAST. WINDS HAVE DROPPED OFF AND ALLOWED THE WIND ADVISORY TO
EXPIRE. 43
&&
PREV DISCUSSION... /ISSUED 454 AM CST SUN NOV 24 2013/
DISCUSSION...
COLDER AIRMASS CONTINUES TO DEEPEN OVER SE TX FROM NE TO SW.
AIRMASS IS BECOMING DRIER AND PERHAPS DRIER THAN PREVIOUSLY
FORECASTED BY SHORT RANGE MODELS. MIDNIGHT SFC ANALYSIS HAS 1042MB
SFC HIGH OVER THE C PLAINS HEADED INTO THE MIDWEST. DUE TO THE
DRIER BOUNDARY LAYER...NOT EXPECTING MUCH IN THE WAY OF PRECIP
TODAY WITH LOW/MID LEVEL CLOUD DECK. COLD ADVECTION AND CLOUD
COVER WILL KEEP MAX TEMPS IN THE 40S TODAY.
UPPER AIR ANALYSIS AND WATER VAPOR IMAGERY SHOW CLOSED UPPER LOW
OVER THE DESERT SW. SEEMS THE LOW HAS WEAKEN A TOUCH WITH 500MB
HEIGHTS A BIT HIGHER THAN 24 HRS AGO. THAT SAID...LEAD JET STREAK
AND SHORT WAVE ARE CAUSING FROZEN PRECIP OVER W TX INTO C TX THIS
MORNING. THIS LEAD SHORT WAVE DOES NOT SEEM QUITE AS STRONG AS
PREVIOUS MODEL RUNS HAD INDICATED. SEEMS THAT PRECIP OVERNIGHT MAY
NOT QUITE AS GREAT AND LARGE SCALE LIFT IS NOT AS STRONG. AS SUCH
IT WILL TAKE LONGER FOR THE BOUNDARY LAYER TO MOISTEN THROUGH WET
BULB THERMODYNAMICS. DO NOT THINK THE THREAT FOR RAIN/SLEET OR
FREEZING RAIN MIX WILL BE THAT HIGH MONDAY MORNING. MODEL
SOUNDINGS FROM NAM/GFS STILL SUPPORT MIXED PRECIP TYPE FROM
COLLEGE STATION TO CROCKETT BUT THAT MAY BE A BIT MORE OF A
STRETCH. LIKELY HAVE ALL RAIN IN THESE AREAS. MIN TEMPS WILL BE
TRICKY AS WELL. WILL STICK CLOSER TO COLDER GFS MOS NUMBERS IN
FORECAST BUT MAY NEED SOME THERMODYNAMICS TO HELP GET THAT COLD
AT THE SURFACE. IF THAT HAPPENS WHILE NO ACCUMULATION IS
EXPECTED...IMPACTS WILL BE FOR ELEVATED BRIDGES/OVERPASSES WITH A
LIGHT GLAZE IF ANYTHING.
ON MONDAY MAIN UPPER LEVEL JET AND UPPER LEVEL LOW BEGIN TO MOVE
INTO THE AREA. LARGE SCALE ASCENT WILL ONLY INCREASE WITH LARGE
OMEGA AND QUITE A BIT OF Q-VECTOR CONVERGENCE SPREADING OVER THE
AREA. ISENTROPIC LIFT OVER STALLED FRONT IN THE GULF WILL ONLY
INCREASE DUE TO THE STRONG FORCING. NAM/ECMWF STILL KEEP COASTAL
LOW CLOSER TO THE COAST THAN THE GFS. NOTICED SEVERAL ENHANCED
RAIN BANDS THAT SET UP OVER THE AREA. CROSS-SECTIONS DO SHOW SOME
FRONTOGENETIC FORCING CO-LOCATED WITH AREAS OF POSSIBLE CSI. HI-
RES WRF-ARW SHOWS SOME VERY SIMILAR BANDED FEATURES AND WOULD NOT
BE SURPRISED IF THERE WERE SOME AREAS OF ENHANCED PRECIP DUE TO
BANDING. FORECAST WILL STICK WITH 80/90 POPS ON MONDAY. PRECIP
TOTALS AGAIN LOOK TO BE IN THE 1-2 INCH RANGE FOR MONDAY. FEEL
MOST AREAS SHOULD BE ABLE TO HANDLE THIS MUCH PRECIP ESPECIALLY
OVER 6-12 HRS. THE COASTAL LOW WILL ALSO SUPPORT EASTERLY WINDS TO
THE NORTH OF IT WHICH COULD INCREASE TIDE LEVELS. WILL AGAIN NEED
TO MONITOR FOR THE POSSIBILITY OF COASTAL FLOODING MON/TUE.
FORECASTING WINTER PRECIP FOR THE AREA ON TUESDAY IS NOT VERY
STRAIGHT FORWARD. ALL OF THE MODELS STILL HAVE THE UPPER LOW
TRACKING DIRECTLY OVER THE AREA. IF ANYTHING MAYBE TRACK A BIT
FARTHER SOUTH AS A VORT MAX OVER MEXICO HELPS PULL THE LOW SOUTH
MONDAY NIGHT. THE UPPER LOW MAY NOW EVEN BE ABOUT 6 HRS SLOWER
TRACKING ACROSS THE AREA. DO THINK THAT UPWARD VERTICAL MOTION
WILL BE LARGE OVER THE AREA BUT NOT SURE IF THERE WILL BE ENOUGH
MOISTURE FOR THE SYSTEM TO WORK WITH AND IF TEMPS IN THE LOW
LEVELS WILL BE COLD ENOUGH FOR FROZEN PRECIP. RIGHT NOW THINK
NORTHERN AREAS COULD SEE A RAIN/SLEET MIX FROM BASICALLY COLLEGE
STATION TO HUNTSVILLE TO LIVINGSTON. NAM/GFS/ECMWF JUST DO NOT
SEEM TO COOL 925/850MB TEMPS ENOUGH TO STRICTLY SUPPORT FROZEN
PRECIP LIKE RAIN/SLEET/SNOW MIX. BY 18Z TUE TO 00Z WED THE
MID/UPPER LEVELS OF THE ATMOSPHERE DRY OUT ENOUGH SO THAT ONLY
PRECIP WILL BE RAIN THAT MAY HAPPEN TO FALL THROUGH A SUB-FREEZING
LAYER THICK ENOUGH TO FREEZE. WITH THAT SAID...DO NOT WANT TO
UNDER-ESTIMATE THE EFFECTS OF DYNAMICAL LIFT FROM THE UPPER LOW
AND ANY WET BULBING THAT MAY OCCUR UNDER THE LOW. MAY NEED TO
MONITOR FURTHER BUT COULD SEE THE FROZEN PRECIP LINE DROP FARTHER
SOUTH ESPECIALLY IF THERE IS MORE MOISTURE TO WORK WITH AND IT
LOOKS LIKE TEMPS MAY BE COLD ENOUGH. OVERALL THINK ANY FROZEN
PRECIP WILL BE LIGHT AND SHOULD NOT ACCUMULATE. MAIN ISSUES MAY
STILL BE ELEVATED SURFACES LIKE OVERPASSES.
ATMOSPHERE REALLY DRIES OUT 00Z-12Z WED WITH NEXT FRONT PUSHING
THROUGH. HIGH PRESSURE THEN BUILDS INTO THE OZARKS WED NIGHT INTO
THUR. SHOULD HAVE CLEAR SKIES AND MUCH CALMER WINDS. LOOKS LIKE
THANKSGIVING DAY COULD START OUT WITH AN AREA WIDE FREEZE. EVEN
FRIDAY MORNING MAY HAVE SOME SPOTS WITH FREEZING TEMPS. BELOW
NORMAL TEMPS SHOULD CONTINUE INTO THE WEEKEND WITH RETURN FLOW
FINALLY SETTING UP NEXT SATURDAY INTO SUNDAY. 39
&&
MARINE...
STRONG NORTHEAST WINDS CONTINUE THIS MORNING ACROSS THE COASTAL
WATERS THIS MORNING AND ADVISORIES WILL CONTINUE FOR ALL WATERS
THROUGH MID MORNING. WINDS ALONG THE IMMEDIATE COAST WILL BEGIN TO
WEAKEN AND THE BAYS ARE EXPECTED TO FALL BELOW ADVISORY CRITERIA.
WINDS ACROSS THE COASTAL WATERS WILL REMAIN ABOVE ADVISORY
CRITERIA THROUGH THE DAY TODAY AND ADVISORIES WILL LIKELY NEED TO
BE CARRIED EVEN LONGER...PARTICULARLY FOR THE OFFSHORE WATERS
WHERE ADVISORY CONDITIONS ARE EXPECTED THROUGH MID WEEK. FORECAST
MODELS CONTINUE TO BRING THE UPPER LEVEL LOW FURTHER SOUTH WHICH
WILL SHIFT THE COASTAL LOW SOUTH OF OUR MARINE ZONES AND ALLOW FOR
NORTHEAST WINDS THROUGH TUESDAY WHICH WILL BECOME NORTHWESTERLY AS
THE UPPER LOW MOVES OFF TO OUR EAST. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 32 38 34 45 31 / 60 90 60 30 10
HOUSTON (IAH) 36 42 36 45 34 / 40 90 70 50 10
GALVESTON (GLS) 43 48 41 48 38 / 40 80 80 60 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH MONDAY AFTERNOON FOR
THE FOLLOWING ZONES: MATAGORDA BAY.
SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 6 PM CST THIS EVENING
FOR THE FOLLOWING ZONES: GALVESTON BAY.
SMALL CRAFT ADVISORY UNTIL 6 PM CST THIS EVENING FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT
20 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION FROM 6 PM CST THIS EVENING
THROUGH MONDAY AFTERNOON FOR THE FOLLOWING ZONES: WATERS
FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL 6 PM CST MONDAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO
60 NM.
&&
$$
DISCUSSION...43
AVIATION/MARINE...31
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1118 AM CST SUN NOV 24 2013
.UPDATE...
SEE MORNING UPDATE.
&&
.DISCUSSION...
12Z UPPER AIR DATA SHOWS GREATER SATURATION AT 850 MB AND 700 MB
THAT YESTERDAY. A WELL DEFINED S/WV IS ALSO NOTED AT BOTH 850 MB
AND 700 MB. THE RAP 13 SHOWS AN AREA OF PRECIP MOVING INTO THE
REGION THIS AFTN INTO THIS EVENING BUT THERE IS LAYER OF VERY DRY
AIR NEAR THE SURFACE THAT WILL NEED TO BE OVERCOME. THINK CHANCE
POPS ARE THE WAY TO GO AND WILL TAPER HIGHER POPS WEST AND LOWER
POPS EAST. WINDS HAVE DROPPED OFF AND ALLOWED THE WIND ADVISORY TO
EXPIRE. 43
&&
.PREV DISCUSSION... /ISSUED 538 AM CST SUN NOV 24 2013/
DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION.
AVIATION...
VFR CONDITIONS AREAWIDE THIS MORNING AND THESE SHOULD PERSIST
THROUGH MUCH OF THE DAY WITH MID LEVEL OVERCAST. A SHORTWAVE
DISTURBANCE APPROACHING FROM THE SOUTHWEST WILL ALLOW FOR A FEW
LIGHT SHOWERS ACROSS THE AREA WITH SOME VIRGA DUE TO VERY DRY AIR
AT LOW LEVELS. CIGS WILL BEGIN TO FALL OVERNIGHT WITH LIGHT RAIN
MOVING IN AS THE MAIN UPPER LEVEL SYSTEM BEGINS TO APPROACH. MODEL
SOUNDINGS SUPPORT A POTENTIAL RA/PL MIX FOR CLL EARLY MONDAY
MORNING BUT FEEL THIS IS OVERDONE AND PRECIP SHOULD REMAIN AS
RAIN. CHANCES FOR WINTRY MIX AT CLL/UTS LOOK BETTER FOR TUESDAY.
38
PREV DISCUSSION... /ISSUED 454 AM CST SUN NOV 24 2013/
DISCUSSION...
COLDER AIRMASS CONTINUES TO DEEPEN OVER SE TX FROM NE TO SW.
AIRMASS IS BECOMING DRIER AND PERHAPS DRIER THAN PREVIOUSLY
FORECASTED BY SHORT RANGE MODELS. MIDNIGHT SFC ANALYSIS HAS 1042MB
SFC HIGH OVER THE C PLAINS HEADED INTO THE MIDWEST. DUE TO THE
DRIER BOUNDARY LAYER...NOT EXPECTING MUCH IN THE WAY OF PRECIP
TODAY WITH LOW/MID LEVEL CLOUD DECK. COLD ADVECTION AND CLOUD
COVER WILL KEEP MAX TEMPS IN THE 40S TODAY.
UPPER AIR ANALYSIS AND WATER VAPOR IMAGERY SHOW CLOSED UPPER LOW
OVER THE DESERT SW. SEEMS THE LOW HAS WEAKEN A TOUCH WITH 500MB
HEIGHTS A BIT HIGHER THAN 24 HRS AGO. THAT SAID...LEAD JET STREAK
AND SHORT WAVE ARE CAUSING FROZEN PRECIP OVER W TX INTO C TX THIS
MORNING. THIS LEAD SHORT WAVE DOES NOT SEEM QUITE AS STRONG AS
PREVIOUS MODEL RUNS HAD INDICATED. SEEMS THAT PRECIP OVERNIGHT MAY
NOT QUITE AS GREAT AND LARGE SCALE LIFT IS NOT AS STRONG. AS SUCH
IT WILL TAKE LONGER FOR THE BOUNDARY LAYER TO MOISTEN THROUGH WET
BULB THERMODYNAMICS. DO NOT THINK THE THREAT FOR RAIN/SLEET OR
FREEZING RAIN MIX WILL BE THAT HIGH MONDAY MORNING. MODEL
SOUNDINGS FROM NAM/GFS STILL SUPPORT MIXED PRECIP TYPE FROM
COLLEGE STATION TO CROCKETT BUT THAT MAY BE A BIT MORE OF A
STRETCH. LIKELY HAVE ALL RAIN IN THESE AREAS. MIN TEMPS WILL BE
TRICKY AS WELL. WILL STICK CLOSER TO COLDER GFS MOS NUMBERS IN
FORECAST BUT MAY NEED SOME THERMODYNAMICS TO HELP GET THAT COLD
AT THE SURFACE. IF THAT HAPPENS WHILE NO ACCUMULATION IS
EXPECTED...IMPACTS WILL BE FOR ELEVATED BRIDGES/OVERPASSES WITH A
LIGHT GLAZE IF ANYTHING.
ON MONDAY MAIN UPPER LEVEL JET AND UPPER LEVEL LOW BEGIN TO MOVE
INTO THE AREA. LARGE SCALE ASCENT WILL ONLY INCREASE WITH LARGE
OMEGA AND QUITE A BIT OF Q-VECTOR CONVERGENCE SPREADING OVER THE
AREA. ISENTROPIC LIFT OVER STALLED FRONT IN THE GULF WILL ONLY
INCREASE DUE TO THE STRONG FORCING. NAM/ECMWF STILL KEEP COASTAL
LOW CLOSER TO THE COAST THAN THE GFS. NOTICED SEVERAL ENHANCED
RAIN BANDS THAT SET UP OVER THE AREA. CROSS-SECTIONS DO SHOW SOME
FRONTOGENETIC FORCING CO-LOCATED WITH AREAS OF POSSIBLE CSI. HI-
RES WRF-ARW SHOWS SOME VERY SIMILAR BANDED FEATURES AND WOULD NOT
BE SURPRISED IF THERE WERE SOME AREAS OF ENHANCED PRECIP DUE TO
BANDING. FORECAST WILL STICK WITH 80/90 POPS ON MONDAY. PRECIP
TOTALS AGAIN LOOK TO BE IN THE 1-2 INCH RANGE FOR MONDAY. FEEL
MOST AREAS SHOULD BE ABLE TO HANDLE THIS MUCH PRECIP ESPECIALLY
OVER 6-12 HRS. THE COASTAL LOW WILL ALSO SUPPORT EASTERLY WINDS TO
THE NORTH OF IT WHICH COULD INCREASE TIDE LEVELS. WILL AGAIN NEED
TO MONITOR FOR THE POSSIBILITY OF COASTAL FLOODING MON/TUE.
FORECASTING WINTER PRECIP FOR THE AREA ON TUESDAY IS NOT VERY
STRAIGHT FORWARD. ALL OF THE MODELS STILL HAVE THE UPPER LOW
TRACKING DIRECTLY OVER THE AREA. IF ANYTHING MAYBE TRACK A BIT
FARTHER SOUTH AS A VORT MAX OVER MEXICO HELPS PULL THE LOW SOUTH
MONDAY NIGHT. THE UPPER LOW MAY NOW EVEN BE ABOUT 6 HRS SLOWER
TRACKING ACROSS THE AREA. DO THINK THAT UPWARD VERTICAL MOTION
WILL BE LARGE OVER THE AREA BUT NOT SURE IF THERE WILL BE ENOUGH
MOISTURE FOR THE SYSTEM TO WORK WITH AND IF TEMPS IN THE LOW
LEVELS WILL BE COLD ENOUGH FOR FROZEN PRECIP. RIGHT NOW THINK
NORTHERN AREAS COULD SEE A RAIN/SLEET MIX FROM BASICALLY COLLEGE
STATION TO HUNTSVILLE TO LIVINGSTON. NAM/GFS/ECMWF JUST DO NOT
SEEM TO COOL 925/850MB TEMPS ENOUGH TO STRICTLY SUPPORT FROZEN
PRECIP LIKE RAIN/SLEET/SNOW MIX. BY 18Z TUE TO 00Z WED THE
MID/UPPER LEVELS OF THE ATMOSPHERE DRY OUT ENOUGH SO THAT ONLY
PRECIP WILL BE RAIN THAT MAY HAPPEN TO FALL THROUGH A SUB-FREEZING
LAYER THICK ENOUGH TO FREEZE. WITH THAT SAID...DO NOT WANT TO
UNDER-ESTIMATE THE EFFECTS OF DYNAMICAL LIFT FROM THE UPPER LOW
AND ANY WET BULBING THAT MAY OCCUR UNDER THE LOW. MAY NEED TO
MONITOR FURTHER BUT COULD SEE THE FROZEN PRECIP LINE DROP FARTHER
SOUTH ESPECIALLY IF THERE IS MORE MOISTURE TO WORK WITH AND IT
LOOKS LIKE TEMPS MAY BE COLD ENOUGH. OVERALL THINK ANY FROZEN
PRECIP WILL BE LIGHT AND SHOULD NOT ACCUMULATE. MAIN ISSUES MAY
STILL BE ELEVATED SURFACES LIKE OVERPASSES.
ATMOSPHERE REALLY DRIES OUT 00Z-12Z WED WITH NEXT FRONT PUSHING
THROUGH. HIGH PRESSURE THEN BUILDS INTO THE OZARKS WED NIGHT INTO
THUR. SHOULD HAVE CLEAR SKIES AND MUCH CALMER WINDS. LOOKS LIKE
THANKSGIVING DAY COULD START OUT WITH AN AREA WIDE FREEZE. EVEN
FRIDAY MORNING MAY HAVE SOME SPOTS WITH FREEZING TEMPS. BELOW
NORMAL TEMPS SHOULD CONTINUE INTO THE WEEKEND WITH RETURN FLOW
FINALLY SETTING UP NEXT SATURDAY INTO SUNDAY.
39
MARINE...
STRONG NORTHEAST WINDS CONTINUE THIS MORNING ACROSS THE COASTAL
WATERS THIS MORNING AND ADVISORIES WILL CONTINUE FOR ALL WATERS
THROUGH MID MORNING. WINDS ALONG THE IMMEDIATE COAST WILL BEGIN TO
WEAKEN AND THE BAYS ARE EXPECTED TO FALL BELOW ADVISORY CRITERIA.
WINDS ACROSS THE COASTAL WATERS WILL REMAIN ABOVE ADVISORY
CRITERIA THROUGH THE DAY TODAY AND ADVISORIES WILL LIKELY NEED TO
BE CARRIED EVEN LONGER...PARTICULARLY FOR THE OFFSHORE WATERS
WHERE ADVISORY CONDITIONS ARE EXPECTED THROUGH MID WEEK. FORECAST
MODELS CONTINUE TO BRING THE UPPER LEVEL LOW FURTHER SOUTH WHICH
WILL SHIFT THE COASTAL LOW SOUTH OF OUR MARINE ZONES AND ALLOW FOR
NORTHEAST WINDS THROUGH TUESDAY WHICH WILL BECOME NORTHWESTERLY AS
THE UPPER LOW MOVES OFF TO OUR EAST. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 43 32 38 34 45 / 40 60 90 60 30
HOUSTON (IAH) 47 36 42 36 45 / 20 40 90 70 50
GALVESTON (GLS) 52 43 48 41 48 / 20 40 80 80 60
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH MONDAY AFTERNOON FOR
THE FOLLOWING ZONES: MATAGORDA BAY.
SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 6 PM CST THIS EVENING
FOR THE FOLLOWING ZONES: GALVESTON BAY.
SMALL CRAFT ADVISORY UNTIL 6 PM CST THIS EVENING FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT
20 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION FROM 6 PM CST THIS EVENING
THROUGH MONDAY AFTERNOON FOR THE FOLLOWING ZONES: WATERS
FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL 6 PM CST MONDAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO
60 NM.
&&
$$
DISCUSSION...43
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
201 PM CST SUN NOV 24 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 201 PM CST SUN NOV 24 2013
MAIN SHORT TERM FORECAST CONCERN IS ON PRECIPITATION CHANCES LATER
TONIGHT...ALONG WITH HOW MUCH AND POTENTIAL FOR FREEZING DRIZZLE.
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING ALONG THE WEST COAST OF NORTH AMERICA...SUBTROPICAL
STREAM TROUGH OVER ARIZONA...AND NORTHERN STREAM TROUGHING FROM
CENTRAL CANADA INTO NEW ENGLAND. WITHIN THIS TROUGHING...A FAIRLY
POTENT SHORTWAVE WAS SEEN DIVING SOUTHEAST THROUGH SASKATCHEWAN.
AHEAD OF THIS TROUGH...VAD WIND PROFILES DEPICT 30-45 KT 925MB WINDS
ACROSS THE EASTERN DAKOTAS AND MINNESOTA. THESE WINDS HAVE BEEN
ADVECTING WARMER AIR TOWARDS THE FORECAST AREA...WITH 925MB TEMPS
NOW PER RAP ANALYSIS AT -7 TO -12C...COMPARED TO -12 TO -14C AT 12Z.
AIRMASS REMAINS RELATIVELY DRY...THOUGH...WITH PRECIPITABLE WATER
VALUES JUST BELOW 0.25 INCH ACROSS THE UPPER MIDWEST. UPSTREAM IN
THE WAKE OF THE SHORTWAVE...ANOTHER ARCTIC AIR SURGE WAS BREWING
ACROSS THE NORTHWEST TERRITORIES WHERE TEMPERATURES ARE SITTING IN
THE SINGLE DIGITS AND TEENS ABOVE ZERO.
MODELS ARE IN GOOD AGREEMENT SLIDING THE POTENT SHORTWAVE OVER
SASKATCHEWAN SOUTHEAST INTO NORTHERN PORTIONS OF MN...WI AND MI
MONDAY MORNING...THEN HEADING OFF TO EASTERN ONTARIO DURING THE
AFTERNOON. AS THE SHORTWAVE APPROACHES TONIGHT...SFC/925/850MB WINDS
ALL INCREASE OVER THE FORECAST AREA...SETTING UP FOR A MUCH WARMER
NIGHT. IN ADDITION...THESE WINDS WILL ADVECT IN A TONGUE OF
RELATIVELY HIGHER MOISTURE FROM WESTERN KS AND EASTERN COLORADO...AS
WELL AS FROM UP IN SOUTHERN MANITOBA...NOTED BY PRECIPITABLE WATER
CLIMBING TO AROUND 0.5 INCH. THE HIGHEST PRECIPITABLE WATER IS
CONFINED TO NORTHEAST IOWA AND SOUTHERN WI WHICH WOULD THEREFORE BE
THE GREATEST CONCERN FOR PRECIPITATION. ALBEIT...THE GENERAL LOW
AMOUNT OF PRECIPITABLE WATER WILL LIKELY LIMIT THE AMOUNT OF
PRECIPITATION. REGARDING LIFT...280-290K ISENTROPIC SURFACES DEPICT
AN INCREASE OF NET ADIABATIC OMEGA ACROSS THE FORECAST AREA BETWEEN
06 AND 12Z...THEN SLIDES OFF TO THE SOUTHEAST. GENERAL MODEL
CONSENSUS HAS BEEN HOLDING STEADY SUGGESTING PRECIPITATION BREAKING
OUT ACROSS NORTHEAST IOWA LATE TONIGHT...THEN SPREADING INTO
SOUTHERN AND PERHAPS CENTRAL WISCONSIN MONDAY MORNING. SINCE
SATURATION OCCURS FROM THE LOW TO MID LEVELS OF THE ATMOSPHERE...THE
PRECIPITATION TYPE SHOULD BE MOSTLY SNOW...BUT CANNOT RULE OUT SOME
FREEZING DRIZZLE POSSIBLE EITHER AT THE ONSET OR ON THE NORTH SIDE
OF THE DEEPER MOISTURE. ANOTHER CONCERN IS PRECIPITATION BREAKING
OUT ALONG THE POTENT SHORTWAVES WARM FRONT. 24.12Z GFS/HIRESARW AND
24.15Z SREF ALL SUGGEST THAT AS THE FRONT RUNS INTO LOW LEVEL
STRATUS WHICH DEVELOPED LATE TONIGHT AHEAD OF IT...VERTICAL MOTION
WITH THE FRONT CAN PRODUCE LIGHT PRECIPITATION. THIS WOULD APPEAR TO
BE THE BEST CHANCE TO SEE FREEZING DRIZZLE. MUCH OF THE FORECAST
AREA WOULD HAVE A CONCERN FOR THIS DEVELOPING...INCLUDING NORTHEAST
IA AND SOUTHERN WI WHEN THE SNOW THERE DEPARTS.
GIVEN THAT THE PROBABILITY OF FREEZING DRIZZLE IS LOW AT THIS
TIME...ON THE ORDER OF 20 TO MAYBE 30 PERCENT...HAVE NOT ISSUED ANY
WINTER WEATHER ADVISORIES. FURTHER SHIFTS MAY NEED TO ISSUE
THEM...THOUGH...IF FREEZING DRIZZLE LOOKS MORE LIKELY TO OCCUR.
TEMPERATURE WISE...WE SHOULD SEE TEMPERATURES HOLD EITHER NEARLY
STEADY AND LIKELY RISE AFTER MIDNIGHT AS THE BREEZY SOUTH WINDS
BRING IN WARMER AIR AT THE SURFACE. THERE IS POTENTIAL FOR SOME
CLEARING MONDAY AFTERNOON...WHICH WITH 925MB TEMPS WARMING TO -2 TO -
4C IN THE AFTERNOON...HIGHS SHOULD CLIMB INTO THE 30S IN MOST
LOCATIONS.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 201 PM CST SUN NOV 24 2013
FOCUS OF THE LONG TERM PERIOD IS ON AN ARCTIC COOL SHOT SLATED FOR
TUESDAY INTO WEDNESDAY...AND ANY POSSIBLE PRECIPITATION THURSDAY
INTO THE WEEKEND.
MODELS DEPICT ANOTHER POTENT SHORTWAVE DROPPING OUT OF THE NORTHWEST
TERRITORIES AND DOWN INTO THE FORECAST AREA ON TUESDAY. THIS POTENT
SHORTWAVE REALLY HELPS TO BRING DOWN THE ARCTIC AIR OBSERVED UP
THERE. AT THE SAME TIME...WITH THE ARCTIC COLD FRONTAL PASSAGE
OCCURRING IN THE MORNING...LOW LEVEL MOISTURE GETS TRAPPED. THIS
MOISTURE COMBINED WITH DAYTIME HEATING WILL MANIFEST ITSELF INTO A
FAIRLY WIDESPREAD STRATUS DECK. STEEP LOW LEVEL LAPSE RATES ALONG
WITH THE STRATUS DECK BEING IN THE DENDRITIC GROWTH ZONE IS LIKELY
TO LEAD TO FLURRIES AT A MINIMUM...AND WOULD NOT BE SURPRISED IF
SOME LOW CHANCES OF PRECIPITATION WILL NEED TO BE ADDED.
WITH THE ARCTIC COLD FRONTAL PASSAGE TUESDAY MORNING...EXPECT
TEMPERATURES TO NOT RISE MUCH AND IF ANYTHING WILL LIKELY FALL
DURING THE AFTERNOON HOURS. 925MB TEMPS FALL TO -12C BY 00Z
WEDNESDAY AND TO AROUND -14C BY 12Z WEDNESDAY. THERE IS A CONTINUING
NORTHWEST BREEZE THROUGH THIS PERIOD WHICH WILL TEMPER A BIT ON HOW
COLD WE GET TUESDAY NIGHT...AND LEANED MORE TOWARDS THE MET GUIDANCE
FOR LOWS. ON THE FLIP SIDE...EXPECT COLDER WIND CHILLS BECAUSE OF
THE BREEZE. SOME MODERATION TAKES PLACE IN 925MB TEMPS ON WEDNESDAY
WITH SUN SO THAT TEMPERATURES CAN CLIMB BACK INTO THE LOW TO MID
20S.
THE UPPER FLOW FROM THANKSGIVING AND BEYOND LOOKS TO CHANGE...GOING
FROM THE NORTHWESTERLY PATTERN WE HAVE BEEN IN RECENTLY TOWARDS MORE
ZONAL. THERE ARE EVEN HINTS IN THE 24.12Z ECMWF OF THE FLOW BACKING
SOUTHWESTERLY EARLY NEXT WEEK. THIS PATTERN CHANGE WILL HELP
DISLODGE SOME OF THE COLD AIR...THUS FOLLOWED A CONSENSUS FORECAST
DEPICTING A GRADUAL MODERATING TREND FOR TEMPERATURES. REGARDING
PRECIPITATION CHANCES...DURING THE PATTERN CHANGE...THERE ARE
SHORTWAVE TROUGHS TRAVERSING ACROSS NORTHERN MN INTO UPPER MI ON
THANKSGIVING AND ON SATURDAY. RIGHT NOW BASED ON THE TRACK WOULD
SUGGEST THE BETTER CHANCES FOR PRECIPITATION WOULD STAY NORTH OF THE
FORECAST AREA. HOWEVER...THAT SATURDAY SHORTWAVE TROUGH APPEARS TO
TAKE A BIT FARTHER SOUTH TRACK COMPARED TO THE ONE ON
THANKSGIVING...THUS 20 PERCENT CHANCES OF SNOW ARE IN THE
FORECAST FOR BOTH SATURDAY AND SATURDAY NIGHT. FRIDAY AND SUNDAY
APPEAR DRY AT THIS TIME BETWEEN SHORTWAVE TROUGHS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1157 AM CST SUN NOV 24 2013
CHALLENGING FORECAST PERIOD WITH RAPID AIR MASS CHANGE AND A
COUPLE OF WEATHER SYSTEMS AFFECTING THE TAFS. A WEATHER SYSTEM
WILL MOVE THROUGH THE REGION DURING THE SECOND PORTION OF THE TAF
PERIOD FROM 25.06-18Z AND IS DISJOINTED. SOME MOISTURE RETURN IN
THE LOW LEVELS WILL OCCUR ON VERY STRONG SOUTHWEST FLOW AHEAD OF A
SYSTEM APPROACHING FROM CANADA. THIS MOISTURE HAS THE POTENTIAL
FOR AN IFR OR LOW MVFR CIG AT THE TAF SITES. BECAUSE THE MOISTURE
IS STILL QUITE FAR WEST /COLORADO/...AND SO MUCH MUST COME
TOGETHER...THE CONFIDENCE IS LOWER ON THE EXACT HEIGHT THAT THE
CIGS WILL COME IN AROUND SUNRISE. WITH LIFT ALSO IN THE
AREA...SHOULD ENOUGH SATURATION OCCUR...FREEZING DRIZZLE WOULD BE
POSSIBLE DURING THE MONDAY MORNING PERIOD. AT THIS TIME THE
FEELING IS THAT THE MOISTURE IS NOT DEEP ENOUGH TO GROW DROPS
LARGE ENOUGH TO FALL OUT AS FZDZ. HOWEVER...THE POTENTIAL IS
THERE.
THE SYSTEM WILL PRODUCE VERY STRONG LOW LEVEL WINDS IN THE LOWEST
FEW THOUSAND FEET AGL...AND THUS LLWS WAS CONTINUED OVERNIGHT.
THIS LLWS FORECAST IS OF HIGHER CONFIDENCE.
THE PERIOD ENDS WITH A COLD FRONT PASSAGE...WINDS BECOMING
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BAUMGARDT