Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/16/13
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
1015 AM PST MON JAN 14 2013
...ONE MORE ROUND OF COOL TEMPERATURES EXPECTED...
.DISCUSSION...AS OF 9:35 AM PST MONDAY...TEMPEARTURES ENDED UP
COLD IN MANY SPOTS ACROSS OUR AREA...HOWEVER THE WIND CAME UP MORE
THAN FORECAST FOR PARTS OF THE BAY AND THE NORTH BAY. THIS
PREVENTED SOME LOCATIONS FROM DROPPING AS LOW AS THEY WERE SUNDAY
MORNING.
WIDESPREAD SUNSHINE CAN BE EXPECTED TODAY WITH A FEW DEGREES OF
WARMING COMPARED TO YESTERDAY. GENERALLY LOW TO MID 50S INSTEAD OF
UPPER 40S TO LOWER 50S WHICH WE SAW FOR SUNDAY`S HIGHS.
TONIGHT WILL BE THE COOLEST NIGHT FOR THE NEXT SEVEN DAYS AS A
RIDGE OF HIGH PRESSURE BUILDS BACK TO OUR AREA AND HELPS TO PUSH
TEMPERATURES TO ABOVE NORMAL READINGS FOR THE SECOND HALF OF THE
WEEK. TONIGHT DUE TO FAIRLY LIGHT WINDS AND CLEAR SKIES WE WILL
SEE MOST LOCATIONS BACK IN THE 30S WITH A FEW 20S STILL EXPECTED
FOR PARTS OF THE SOUTHERN SANTA CLARA VALLEY DOWN THROUGH THE
SOUTHERN SALINAS VALLEY. WILL PROBABLY ISSUE ANOTHER FREEZE
WARNING FOR THOSE LOCATIONS. WILL PROBABLY DO A MINOR UPDATE TO
LOWS TONIGHT AS A FEW SHORELINE LOCATIONS LOOK TO BE A BIT TOO
COOL.
.PREVIOUS DISCUSSION...HAVE CANCELLED THE FROST
ADVISORY FOR SAN FRANCISCO AND THE FREEZE WARNING FOR THE SAN
FRANCISCO SHORELINE. THERE HAS BEEN ENOUGH WIND TO KEEP THE
ATMOSPHERE MIXED...SO WHILE THE DEW PTS ARE VERY LOW TEMPERATURES
WILL REMAIN A BIT WARMER THAN EXPECTED. HAVE KEPT THE FREEZE
WARNING GOING TO 9 AM FOR THE INLAND VALLEYS OF THE DISTRICT AS
WELL AS THE SANTA CRUZ/MONTEREY COASTLINE. THE FREEZE WARNING FOR
THE NORTH BAY VALLEYS AND THE EAST BAY VALLEYS IS MARGINAL...BUT
IF THE WIND DIES OFF...TEMPERATURES WILL DROP RAPIDLY IN THE VERY
DRY AIRMASS. THE HRRR MODEL AND THE 00Z WRF BOTH ARE FORECASTING
LIGHT SFC WINDS THIS MORNING...SO WE WILL SEE HOW THIS PANS OUT.
DRY WEATHER WILL BE THE RULE FOR THE UPCOMING WEEK. A STRONG
RIDGE...CLEARLY SEEN ON WATER VAPOR IMAGERY IS CENTERED AROUND
140W...WITH THE RIDGE REACHING INTO ALASKA. INTERESTING TO NOTE
HOW FAR NORTH WARM AIR IS BEING ADVECTED INTO ALASKA...FAIRBANKS
IS CURRENTLY A (RELATIVELY) BALMY 28 DEGREES...WHEREAS THE AVERAGE
LOW IS -14 DEGREES! IN FACT...SAN MARTIN (BETWEEN MORGAN HILL AND
GILROY) IS THE SAME TEMPERATURE AS FAIRBANKS AT THIS TIME...VERY
RARELY SEEN IN THE MIDDLE OF JANUARY!
THE RIDGE WILL SLOWLY EDGE EAST...TO A POSITION ALONG THE COAST BY
THURSDAY...THEN REMAIN OVER THE WEST COAST RIGHT THROUGH THE
WEEKEND. AFTER ANOTHER COLD NIGHT TONIGHT...DEPENDING ON THE
WIND...TEMPERATURES WILL SLOWLY WARM THE REMAINDER OF THE WEEK AND
INTO THE WEEKEND. BOTH THE GFS AND ECMWF BEGIN TO BREAK DOWN THE
RIDGE BY THE MIDDLE OF NEXT WEEK (JANUARY 23).
&&
.AVIATION...AS OF 10:15 AM PST MONDAY...CLEAR SKIES AND OFFSHORE
FLOW WILL CONTINUE ACROSS AREA TERMINALS TODAY AS HIGH PRESSURE
CONTINUES TO BUILD INTO THE GREAT BASIN. THE DRY AIRMASS WILL
MAINTAIN VFR CONDITIONS THROUGH THE FORECAST PERIOD. HIGH
CONFIDENCE.
VICINITY OF KSFO...VFR CONDITIONS EXPECTED THROUGH THE FORECAST
PERIOD. EASTERLY WINDS WILL CONTINUE THROUGH EARLY THIS MORNING
BECOMING VARIABLE IN THE AFTERNOON. LIGHT OFFSHORE FLOW EXPECTED
OVERNIGHT. MODERATE CONFIDENCE IN REGARDS TO WINDS.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR CONDITIONS EXPECTED THROUGH THE
FORECAST PERIOD. OFFSHORE FLOW WILL BECOME VARIABLE THIS AFTERNOON
WITH EASTERLY WINDS ANTICIPATED TO RETURN TONIGHT.
&&
.CLIMATE...HERE ARE THE RECORD LOW TEMPERATURES FOR JANUARY 14TH
AT SELECTED LOCATIONS...
SAN FRANCISCO BAY AREA
.LOCATION....................JAN 14
SANTA ROSA.................21/1963
KENTFIELD..................25/1949
SAN RAFAEL.................28/2007
NAPA.......................24/1963
SAN FRANCISCO..............29/1888
SFO........................31/1963
OAKLAND....................33/2007
OAKLAND AIRPORT............28/2007
RICHMOND...................31/1955
LIVERMORE..................21/1963
MOUNTAIN VIEW..............28/2007
SAN JOSE...................28/1997
GILROY.....................19/1963
MONTEREY BAY AREA
.LOCATION....................JAN 14
MONTEREY...................30/1997
SANTA CRUZ.................22/1963
SALINAS....................24/2007
SALINAS AIRPORT............25/2007
KING CITY..................17/2007
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
$$
PUBLIC FORECAST: STROBIN
AVIATION/MARINE: CW
CLIMATE: HENDERSON/BELL
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
941 AM PST MON JAN 14 2013
...ONE MORE ROUND OF COOL TEMPERATURES EXPECTED...
.DISCUSSION...AS OF 9:35 AM PST MONDAY...TEMPEARTURES ENDED UP
COLD IN MANY SPOTS ACROSS OUR AREA...HOWEVER THE WIND CAME UP MORE
THAN FORECAST FOR PARTS OF THE BAY AND THE NORTH BAY. THIS
PREVENTED SOME LOCATIONS FROM DROPPING AS LOW AS THEY WERE SUNDAY
MORNING.
WIDESPREAD SUNSHINE CAN BE EXPECTED TODAY WITH A FEW DEGREES OF
WARMING COMPARED TO YESTERDAY. GENERALLY LOW TO MID 50S INSTEAD OF
UPPER 40S TO LOWER 50S WHICH WE SAW FOR SUNDAY`S HIGHS.
TONIGHT WILL BE THE COOLEST NIGHT FOR THE NEXT SEVEN DAYS AS A
RIDGE OF HIGH PRESSURE BUILDS BACK TO OUR AREA AND HELPS TO PUSH
TEMPERATURES TO ABOVE NORMAL READINGS FOR THE SECOND HALF OF THE
WEEK. TONIGHT DUE TO FAIRLY LIGHT WINDS AND CLEAR SKIES WE WILL
SEE MOST LOCATIONS BACK IN THE 30S WITH A FEW 20S STILL EXPECTED
FOR PARTS OF THE SOUTHERN SANTA CLARA VALLEY DOWN THROUGH THE
SOUTHERN SALINAS VALLEY. WILL PROBABLY ISSUE ANOTHER FREEZE
WARNING FOR THOSE LOCATIONS. WILL PROBABLY DO A MINOR UPDATE TO
LOWS TONIGHT AS A FEW SHORELINE LOCATIONS LOOK TO BE A BIT TOO
COOL.
.PREVIOUS DISCUSSION...HAVE CANCELLED THE FROST
ADVISORY FOR SAN FRANCISCO AND THE FREEZE WARNING FOR THE SAN
FRANCISCO SHORELINE. THERE HAS BEEN ENOUGH WIND TO KEEP THE
ATMOSPHERE MIXED...SO WHILE THE DEW PTS ARE VERY LOW TEMPERATURES
WILL REMAIN A BIT WARMER THAN EXPECTED. HAVE KEPT THE FREEZE
WARNING GOING TO 9 AM FOR THE INLAND VALLEYS OF THE DISTRICT AS
WELL AS THE SANTA CRUZ/MONTEREY COASTLINE. THE FREEZE WARNING FOR
THE NORTH BAY VALLEYS AND THE EAST BAY VALLEYS IS MARGINAL...BUT
IF THE WIND DIES OFF...TEMPERATURES WILL DROP RAPIDLY IN THE VERY
DRY AIRMASS. THE HRRR MODEL AND THE 00Z WRF BOTH ARE FORECASTING
LIGHT SFC WINDS THIS MORNING...SO WE WILL SEE HOW THIS PANS OUT.
DRY WEATHER WILL BE THE RULE FOR THE UPCOMING WEEK. A STRONG
RIDGE...CLEARLY SEEN ON WATER VAPOR IMAGERY IS CENTERED AROUND
140W...WITH THE RIDGE REACHING INTO ALASKA. INTERESTING TO NOTE
HOW FAR NORTH WARM AIR IS BEING ADVECTED INTO ALASKA...FAIRBANKS
IS CURRENTLY A (RELATIVELY) BALMY 28 DEGREES...WHEREAS THE AVERAGE
LOW IS -14 DEGREES! IN FACT...SAN MARTIN (BETWEEN MORGAN HILL AND
GILROY) IS THE SAME TEMPERATURE AS FAIRBANKS AT THIS TIME...VERY
RARELY SEEN IN THE MIDDLE OF JANUARY!
THE RIDGE WILL SLOWLY EDGE EAST...TO A POSITION ALONG THE COAST BY
THURSDAY...THEN REMAIN OVER THE WEST COAST RIGHT THROUGH THE
WEEKEND. AFTER ANOTHER COLD NIGHT TONIGHT...DEPENDING ON THE
WIND...TEMPERATURES WILL SLOWLY WARM THE REMAINDER OF THE WEEK AND
INTO THE WEEKEND. BOTH THE GFS AND ECMWF BEGIN TO BREAK DOWN THE
RIDGE BY THE MIDDLE OF NEXT WEEK (JANUARY 23).
&&
.AVIATION...AS OF 3:15 AM PST MONDAY...VERY DRY AIRMASS IN PLACE
THIS MORNING WITH CLEAR SKIES AND VFR CONDITIONS. CURRENT TAF
PACKAGE WILL CONTINUE VFR THROUGH THE FORECAST PERIOD. ONLY TRICKY
PART ARE THE EASTERLY WINDS...ESP AROUND SAN FRANCISCO BAY. CONF HIGH.
VICINITY OF KSFO...VFR CONDITIONS. WINDS AS OF 11Z ARE SE AROUND
THE BAY. WILL KEEP SE PREVAILING...BUT MODEL GUIDANCE SUGGESTS A
NE FLOW AROUND 10 KT LATER THIS MORNING. CONF IS MARGINAL AND WILL
LEAVE THE NE FLOW OUT FOR NOW. WILL MONITOR AND AMEND SFO IF
NEEDED. OTHERWISE...NW FLOW LATER TODAY.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR CONDITIONS.
&&
.CLIMATE...HERE ARE THE RECORD LOW TEMPERATURES FOR JANUARY 14TH
AT SELECTED LOCATIONS...
SAN FRANCISCO BAY AREA
.LOCATION....................JAN 14
SANTA ROSA.................21/1963
KENTFIELD..................25/1949
SAN RAFAEL.................28/2007
NAPA.......................24/1963
SAN FRANCISCO..............29/1888
SFO........................31/1963
OAKLAND....................33/2007
OAKLAND AIRPORT............28/2007
RICHMOND...................31/1955
LIVERMORE..................21/1963
MOUNTAIN VIEW..............28/2007
SAN JOSE...................28/1997
GILROY.....................19/1963
MONTEREY BAY AREA
.LOCATION....................JAN 14
MONTEREY...................30/1997
SANTA CRUZ.................22/1963
SALINAS....................24/2007
SALINAS AIRPORT............25/2007
KING CITY..................17/2007
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
$$
PUBLIC FORECAST: STROBIN
AVIATION/MARINE: MM
CLIMATE: HENDERSON/BELL
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT:
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WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
438 AM PST MON JAN 14 2013
...COLD TEMPERATURES THIS MORNING FOR MANY LOCATIONS...
.DISCUSSION...AS OF 4:15 AM PST MONDAY...HAVE CANCELLED THE FROST
ADVISORY FOR SAN FRANCISCO AND THE FREEZE WARNING FOR THE SAN
FRANCISCO SHORELINE. THERE HAS BEEN ENOUGH WIND TO KEEP THE
ATMOSPHERE MIXED...SO WHILE THE DEW PTS ARE VERY LOW TEMPERATURES
WILL REMAIN A BIT WARMER THAN EXPECTED. HAVE KEPT THE FREEZE
WARNING GOING TO 9 AM FOR THE INLAND VALLEYS OF THE DISTRICT AS
WELL AS THE SANTA CRUZ/MONTEREY COASTLINE. THE FREEZE WARNING FOR
THE NORTH BAY VALLEYS AND THE EAST BAY VALLEYS IS MARGINAL...BUT
IF THE WIND DIES OFF...TEMPERATURES WILL DROP RAPIDLY IN THE VERY
DRY AIRMASS. THE HRRR MODEL AND THE 00Z WRF BOTH ARE FORECASTING
LIGHT SFC WINDS THIS MORNING...SO WE WILL SEE HOW THIS PANS OUT.
DRY WEATHER WILL BE THE RULE FOR THE UPCOMING WEEK. A STRONG
RIDGE...CLEARLY SEEN ON WATER VAPOR IMAGERY IS CENTERED AROUND
140W...WITH THE RIDGE REACHING INTO ALASKA. INTERESTING TO NOTE
HOW FAR NORTH WARM AIR IS BEING ADVECTED INTO ALASKA...FAIRBANKS
IS CURRENTLY A (RELATIVELY) BALMY 28 DEGREES...WHEREAS THE AVERAGE
LOW IS -14 DEGREES! IN FACT...SAN MARTIN (BETWEEN MORGAN HILL AND
GILROY) IS THE SAME TEMPERATURE AS FAIRBANKS AT THIS TIME...VERY
RARELY SEEN IN THE MIDDLE OF JANUARY!
THE RIDGE WILL SLOWLY EDGE EAST...TO A POSITION ALONG THE COAST BY
THURSDAY...THEN REMAIN OVER THE WEST COAST RIGHT THROUGH THE
WEEKEND. AFTER ANOTHER COLD NIGHT TONIGHT...DEPENDING ON THE
WIND...TEMPERATURES WILL SLOWLY WARM THE REMAINDER OF THE WEEK AND
INTO THE WEEKEND. BOTH THE GFS AND ECMWF BEGIN TO BREAK DOWN THE
RIDGE BY THE MIDDLE OF NEXT WEEK (JANUARY 23).
&&
.AVIATION...AS OF 3:15 AM PST MONDAY...VERY DRY AIRMASS IN PLACE
THIS MORNING WITH CLEAR SKIES AND VFR CONDITIONS. CURRENT TAF
PACKAGE WILL CONTINUE VFR THROUGH THE FORECAST PERIOD. ONLY TRICKY
PART ARE THE EASTERLY WINDS...ESP AROUND SAN FRANCISCO BAY. CONF HIGH.
VICINITY OF KSFO...VFR CONDITIONS. WINDS AS OF 11Z ARE SE AROUND
THE BAY. WILL KEEP SE PREVAILING...BUT MODEL GUIDANCE SUGGESTS A
NE FLOW AROUND 10 KT LATER THIS MORNING. CONF IS MARGINAL AND WILL
LEAVE THE NE FLOW OUT FOR NOW. WILL MONITOR AND AMEND SFO IF
NEEDED. OTHERWISE...NW FLOW LATER TODAY.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR CONDITIONS.
&&
.CLIMATE...HERE ARE THE RECORD LOW TEMPERATURES FOR JANUARY 14TH
AT SELECTED LOCATIONS...
SAN FRANCISCO BAY AREA
.LOCATION....................JAN 14
SANTA ROSA.................21/1963
KENTFIELD..................25/1949
SAN RAFAEL.................28/2007
NAPA.......................24/1963
SAN FRANCISCO..............29/1888
SFO........................31/1963
OAKLAND....................33/2007
OAKLAND AIRPORT............28/2007
RICHMOND...................31/1955
LIVERMORE..................21/1963
MOUNTAIN VIEW..............28/2007
SAN JOSE...................28/1997
GILROY.....................19/1963
MONTEREY BAY AREA
.LOCATION....................JAN 14
MONTEREY...................30/1997
SANTA CRUZ.................22/1963
SALINAS....................24/2007
SALINAS AIRPORT............25/2007
KING CITY..................17/2007
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...FREEZE WARNING...INTERIOR VALLEYS OF THE SAN FRANCISCO
AND MONTEREY BAY AREAS AND THE SANTA
CRUZ/MONTEREY COASTLINE.
&&
$$
PUBLIC FORECAST: STROBIN
AVIATION/MARINE: MM
CLIMATE: HENDERSON/BELL
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
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WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS PUEBLO CO
802 PM MST TUE JAN 15 2013
.UPDATE...
QUICK UPDATE TO BACK OFF POPS ACROSS THE NM/CO BORDER THROUGH 12Z
IN COORD WITH ABQ...AS LATEST RAP AND NAM12 SHOW ZERO QPF IN THOSE
AREAS IN THE SHORT TERM. -PJC
&&
.PREV DISCUSSION... /ISSUED 320 PM MST TUE JAN 15 2013/
SHORT TERM...
(TONIGHT AND WEDNESDAY)
..WARMER WEATHER IS ON THE WAY...
NICE RECOVERY ACROSS THE PLAINS TODAY...DESPITE A HIGH BKN CLOUD DECK
FROM AN APPROACHING SHORTWAVE. TEMPS RIGHT AROUND FREEZING AS OF MID
AFTERNOON...WHILE MTS AND HIGH VALLEYS GENERALLY REMAIN IN THE SINGLE
DIGITS TO TEENS.
NOT MUCH SHOWING UP ON WSR RIGHT NOW...BUT UPSTREAM OBS OVER NRN COL
AND SRN WY SHOW CIGS DROPPING TO THE 030-040 RANGE...AND EXPECT THE
TREND IN THICKER CLOUD COVER TO CONTINUE THROUGH THIS AFTERNOON AND
INTO THIS EVE. 18Z NAM HAS REALLY BACKED OFF QPF OVER OUR AREA...BUT
STILL EXPECT SOME ISOLD-SCT LIGHT SHSN OVER THE MTS AND PORTIONS OF
TELLER AND NRN EL PASO COUNTIES THIS EVE. VERY LITTLE IF ANY
ACCUMULATION EXPECTED. MAIN IMPACT OF THIS DISTURBANCE WILL BE
THICKER CLOUD COVER...RESULTING IN MILDER OVERNIGHT TEMPS ESPECIALLY
OVER THE PLAINS...AND A PERIOD OF GUSTY WINDS OVER THE PLAINS LATE
TONIGHT AND EARLY WED MORNING. N SIDE OF PIKES PEAK AND PORTIONS OF
TELLER COUNTY AND THE PALMER DVD...ALONG WITH THE WETS AND
SANGRES...WILL SEE THE MOST WIND...AS H7 WINDS FROM 40-50 KTS SWEEP
OVER THE ERN PLAINS TONIGHT.
WED LOOKS COMPLETELY DRY...WITH PLENTY OF SUN FOR THE AFTERNOON. THE
CENTRAL MTS COULD SEE SOME LINGERING CLOUDS THROUGH THE DAY...BUT NO
PRECIP EXPECTED AS AN UPPER RIDGE BUILDS RAPIDLY FROM THE W. IT WILL
BE QUITE MILD FOR THE PLAINS...WITH TEMPS LIKELY IN THE
50S...POSSIBLY NEARING 60 IF THE WINDS ARE A BIT STRONGER FROM THE W.
MTS AND HIGHER ELEVS WEST WILL STILL BE CHILLY...BUT COMPARATIVELY
BALMY AFTER THIS RECENT COLD SNAP...WITH TEMPS LARGELY IN THE 20S.
44
LONG TERM...
(WEDNESDAY NIGHT THROUGH NEXT TUESDAY)
MAINLY A TEMPERATURE FORECAST THE NEXT SEVERAL DAYS AS UPPER RIDGE
REMAINS IN PLACE OVER THE WESTERN U.S. THROUGH AT LEAST THE
MIDDLE OF NEXT WEEK...LEADING TO A DRY FORECAST FOR ALL OF THE
AREA AS WEATHER SYSTEMS ARE SHUNTED WELL NORTHEAST OF THE STATE.
A WEAK WAVE MOVING THROUGH THE RIDGE THU WILL PRODUCE ONLY A FEW
CLOUDS ACROSS THE REGION...THOUGH IT MAY SERVE TO SLOW THE WARM-UP
FOR A DAY...ESPECIALLY OVER THE PLAINS. TEMPS BEGIN TO WARM AGAIN
ON FRI INTO SAT...THEN A WEAK COLD FRONT BACKS INTO THE AT LEAST
THE FAR SOUTHEAST PLAINS SUNDAY...COOLING MAX TEMPS A FEW DEGREES
ALONG AND EAST OF THE MOUNTAINS. UNFORTUNATELY...UPPER RIDING WILL
KEEP COLD...STAGNANT AIR MASS IN PLACE OVER THE SAN LUIS
VALLEY...LEADING TO A MUCH SLOWER WARMING TREND HERE THAN
EVERYWHERE ELSE IN THE REGION. STILL...EXPECT DAYTIME HIGHS AT
ALAMOSA TO CLIMB BACK INTO AT LEAST THE 20S BY THE WEEKEND...AND
OVERNIGHT LOWS WILL IMPROVE INTO MAINLY THE TEENS BELOW ZERO
VERSUS THE MINUS 30F READINGS WE`VE SEEN EARLIER THIS WEEK.
WESTWARD EXTENT OF ARCTIC AIR BECOMES THE CONCERN SUNDAY NIGHT
INTO MONDAY...AS STRONG HIGH PRESSURE DROPS SOUTH INTO THE CENTRAL
PLAINS BEHIND DEEP UPPER TROUGH OVER THE GREAT LAKES. GFS SUGGESTS
ANY COLD AIR OVER THE PLAINS WILL BE VERY SHALLOW AND ERODE BY MON
AFTERNOON AS W-NW SURFACE FLOW AND LEE TROUGH DEVELOP. ECMWF IS
MUCH COLDER...KEEPING THE COLD AIR PINNED AGAINST THE EASTERN
MOUNTAINS UNTIL MONDAY NIGHT...BEFORE WARMER AIR SURGES BACK EAST
TUES. FORECAST LEANS TOWARD THE ECMWF AT THIS POINT AS PROGGED
1047 MB SURFACE HIGH OVER WRN NEB MON AFTERNOON SUGGESTS COLD AIR
WILL BE FAIRLY DEEP AND DIFFICULT TO QUICKLY DISLODGE. WENT WELL
BELOW NUMERICAL MOS GUIDANCE AND SLIGHTLY BELOW MODEL CONSENSUS
TEMPS FOR TUE AFTERNOON...ESPECIALLY NEAR THE KS BORDER. TEMPS
BEGIN TO MODERATE ON TUES AS SURFACE RIDGE MOVES EAST AND LEE
TROUGH REFORMS OVER THE EASTERN PLAINS. --10
AVIATION...MAIN CONCERN WILL BE POTENTIAL FOR SHSN NR KCOS THIS
EVE...ALTHOUGH LATEST COMPUTER GUIDANCE SUGGESTS THAT MOST OF EL
PASO SHOULD STAY DRY TONIGHT. COULD STILL SEE A BRIEF PERIOD OF
MVFR CIGS. WINDS ALSO LOOK TO GET A BIT GUSTY LATE TONIGHT INTO
WED MORNING FROM THE NNW...WITH GUSTS TO 30 KTS OR SO OVER THE HYR
TRRN IN THE PIKES PEAK REGION...POSSIBLY REACHING THE KCOS
TERMINAL AT TIMES. CLEAR AND DRY WX IS EXPECTED FOR ALL SPOTS ON
WED. KALS COULD STILL SEE A BRIEF INTERVAL OF LOW CIGS OR SHALLOW
PC FG EARLY ON WED...BUT CONFIDENCE IN ANY WIDESPREAD RESTRICTION
TO VIS IS TOO LOW TO INCLUDE IN THE ALS TAF. 44
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
81/34
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
355 PM MST MON JAN 14 2013
.SHORT TERM...ELONGATED UPPER TROUGH CURRENTLY MOVING ACROSS
STATE. LATEST RUC QG VERTICAL VELOCITY ANALYSIS SHOWING SOME
LINGERING MID LEVEL ASCENT ACROSSS FAR EASTERN PLAINS. CURRENT
SURFACE OBS AND WEB CAMS DO NOT SHOW SNOW OVER THE AREA THOUGH
LATEST SATELLITE INDICATE A DECENT BATCH OF LOW CLOUDS. ACROSS
MOUNTAINS...WEB CAMS SHOW LIGHT SNOW ALONG THE CONTINENTAL DIVIDE
AND PERHAPS OVER THE GORE AND PARK RANGES OF WESTERN JACKSON
COUNTY. MODELS SHOW THE ASCENT MOVING INTO KANSAS DURING THE
EVENING...SHOULD SEE ANY LINGERING SNOW ACROSS THE PLAINS ENDING
AT THAT TIME. MOISTURE DOES INCREASE OVER MOUNTAINS ON BACK SIDE
OF TROUGH OVERNIGHT...SHOULD SEE SNOW CHANCES INCREASE
PARTICULARLY ZONE 31. WINDS LOOK TO INCREASE AS WELL OVER THE
RIDGES WHICH SHOULD HELP MODERATE THE TEMPERATURES IN AND NEAR
FOOTHILLS. WIND CHILL READINGS TO BE WELL BELOW ZERO...BUT SHOULD
REMAIN BELOW WARNING CRITERIA. OTHERWISE...A COLD NIGHT IS
EXPECTED WITH TEMPERATURES SIMILAR TO THIS MORNINGS READINGS. ON
TUESDAY...THE TROUGH WILL BE IN KANSAS BY 18Z WITH NORTHERLY FLOW
ALOFT OVER COLORADO. THIS SHOULD CONTINUE TO PROVIDE A CHANCE OF
SNOW TO THE MOUNTAINS... MAINLY ZONES 31 AND 33. SNOW AMOUNTS TO
REMAIN LIGHT. ACROSS PLAINS...DRY CONDITIONS TO PREVAIL WITH A
GRADUAL INCREASE IN MID LEVEL CLOUDS. GRADUAL WARMING TREND IS
EXPECTED AS WARM AIR ADVECTS INTO AREA. HOWEVER...INVERSIONS WILL
LIMIT WARMUP IN MOUNTAIN VALLEYS AND LOW LYING AREAS OF THE
PLAINS. ALSO MID LEVEL CLOUDS WILL HINDER WARMUP. CURRENT
TEMPERATURE GRIDS LOOK REASONABLE.
.LONG TERM...THE STRONG NORTH-NORTHEASTERLY FLOW ALOFT IS ON THE
DECREASE TUESDAY NIGHT. ON WEDNESDAY...THE FLOW ALOFT CONTINUES
TO WEAKEN AND BECOMES NORTHWESTERLY. VERY WEAK WEST-NORTHWESTERLY
FLOW ALOFT IS PROGGED WEDNESDAY NIGHT THROUGH THURSDAY NIGHT.
THERE IS BENIGN SYNOPTIC SCALE ENERGY PROGGED ON THE QG VERTICAL
VELOCITY FIELDS THROUGH THE FIVE PERIODS. THE LEVEL FLOW WILL
LIKELY BE A MIX OF NORMAL DIURNAL TRENDS WITH SOME NORTHWESTERLY
DOWNSLOPING THROWN IN TUESDAY NIGHT INTO WEDNESDAY EVENING.
NORMALS PATTERNS ARE LIKELY BY THURSDAY AND THURSDAY NIGHT. FOR
MOISTURE...IT IS PRETTY DEEP TUESDAY EVENING...THEN MOISTURE
DECREASES TOWARDS WEDNESDAY MORNING. FROM WEDNESDAY THROUGH
THURSDAY NIGHT THERE IS VERY LITTLE MOISTURE OVER THE CWA. THERE
IS A TAD OF MEASURABLE SNOWFALL PROGGED ON THE QPF FIELDS TUESDAY
EVENING...THEN NOTHING THROUGH THE REST OF THE PERIODS. FOR POPS
WILL GO WITH 20-50%S FOR THE MOUNTAINS TUESDAY NIGHT...AND 5-20%S
FOR THE PLAINS. FROM WEDNESDAY ONWARD NO POPS. FOR TEMPERATURES
...WEDNESDAY`S HIGHS ARE UP 7-9 C FROM TUESDAY`S. THURSDAY`S HIGHS
ARE SIMILAR TO WEDNESDAY`S. FOR THE LATER DAYS...FRIDAY THROUGH
MONDAY...THE MEDIUM RANGE MODELS KEEP THE FORECAST AREA
IN...MOSTLY...WEAK NORTHWESTERLY FLOW ALOFT ALL FOUR DAYS. A MEAN
TROUGH EAST OF THE CWA GETS A LITTLE CLOSER TO THE CWA...COMPARED
TO PREVIOUS RUNS. THE GFS BRINGS A COLDER AIRMASS INTO THE CWA
SATURDAY AND SUNDAY...THE ECMWF DOES NOT. BOTH MODELS KEEP THE CWA
DRY.
&&
.AVIATION...CEILINGS HAVE SCATTERED OUT AT DEN THOUGH SOME HAZE
STILL IN THE AREA. VFR CONDITIONS TO PREVAIL WITH UNLIMITED
CEILINGS. LIGHT NORTHERLY WINDS TO BECOME SOUTHERLY AS DRAINAGE
PATTERN DEVELOPS. ANY FOG THAT DEVELOPS SHOULD BE CONFINED TO THE
LOW LYING AREAS IN WELD COUNTY. ON TUESDAY...WINDS TO BECOME
NORTHWEST WITH SPEEDS LESS THAN 8 KTS. GRADUAL INCREASE IN MID
LEVEL CLOUDS WITH CEILINGS ABOVE 10000 FEET.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....RJK
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS NEW YORK NY
643 PM EST TUE JAN 15 2013
.SYNOPSIS...
LOW PRESSURE WILL RIDE ALONG THE STALLED FRONT TONIGHT INTO
WEDNESDAY...BRINGING WINTRY WEATHER TO INTERIOR SECTIONS AS IT
MOVES SOUTHEAST OF LONG ISLAND. THE LOW WILL TRACK INTO THE GULF
OF MAINE WEDNESDAY NIGHT. A COLD FRONT WILL CROSS THE REGION LATE
IN THE DAY ON THURSDAY FOLLOWED BY HIGH PRESSURE FRIDAY AND
SATURDAY. A STRONGER COLD FRONT WILL PASS THROUGH ON SUNDAY
FOLLOWED BY HIGH PRESSURE ON MONDAY. ANOTHER FRONTAL SYSTEM MAY
IMPACT THE AREA MONDAY NIGHT INTO TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
CLOUDY SKIES WILL REMAIN AS HIGH PRESSURE MOVES OFF THE NORTHERN
NEW ENGLAND COAST AND WARM AIR ADVECTION ALOFT BEGINS AHEAD OF A
WAVE OF LOW PRESSURE. THIS WAVE WILL BE DEVELOPING OFF THE MID-
ATLANTIC COASTS BY WEDNESDAY MORNING ALONG THAT STALLED FRONT TO
THE SOUTH...EVOLVING AS IT ENCOUNTERS AN INCREASING BAROCLINIC
ENVIRONMENT. WITH INCREASING ISOENTROPIC LIFT...ONSET OF PRECIP
LIKELY 3-6Z FROM SOUTH TO NORTH AFTER NOTING REFLECTIVITY
FORECASTS BY HRRR AND PRECIP FIELDS OF NAM...GFS...ECMWF...AND
CMC. THE INTENSITY OF THE PRECIPITATION INCREASES TOWARDS DAYBREAK
AS THE REGION GETS CLOSER TO THE RIGHT ENTRANCE REGION OF A
160-180 KT JET AROUND 250MB. MID LEVEL FRONTOGENESIS FOCUSED
MOSTLY TO THE NORTH OF THE FORECAST REGION WITH ABRUPT CUTOFFS TO
THE GFS AND NAM SNOWFALL BUT LOWERED TEMPERATURES AND LAYERS
ENOUGH TO ACCOUNT FOR WET BULB COOLING ESPECIALLY AT THE ONSET.
CONCERNING PRECIP TYPE...A COMPLEX FORECAST. GENERALLY THOUGH
EXPECTING SNOW ACROSS THE INTERIOR AREAS...MIXING WITH SLEET TO
THE SOUTHEAST WITH RAIN AND SLEET AT THE COAST. OVERNIGHT...SOME
WARMING IN THE TEMPERATURES ALOFT...GENERALLY BETWEEN 900 AND 700
HPA...WILL PRESENT A LARGE ENOUGH LAYER TO REDUCE THE HYDROMETEORS
TO SLEET ESPECIALLY WITH ANY HIGHER INTENSITY PRECIPITATION. SOME
FREEZING RAIN WILL BE POSSIBLE AS WELL ACROSS A PORTION OF THE
INTERIOR AREAS BUT WILL BE DEPENDENT ON THE AMOUNT OF WET BULB
COOLING AND TEMPERATURES ARE RIGHT NEAR THE FREEZING MARK. SOME
CHANGES ARE POSSIBLE WITH SUBSEQUENT FORECASTS WITH THE
RAIN/SLEET/FREEZING RAIN AND SNOW LINES.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
THE LOW SOUTHEAST OF LONG ISLAND TRAVERSES RIGHT NEAR THE
BENCHMARK OF 40N/-70W AS IT GRADUALLY DEEPENS ON A NORTHEAST
TRACK. THE LOW MOVES TO THE GULF OF MAINE BY WEDNESDAY EVENING
AHEAD OF A DEEPENING UPPER LEVEL TROUGH SINKING INTO THE REGION.
STRONG JET DYNAMICS ALOFT AND THAT RIGHT ENTRANCE REGION WILL MEAN
A LONGER DURATION OF PRECIP...ALTHOUGH NOT MUCH ADDITIONAL
ACCUMULATION EXPECTED BY MID AFTERNOON AND EVENING BY WHICH
TIME...IT WILL BE MOSTLY OVER THE EASTERN SECTIONS OF SOUTHERN CT
AND LONG ISLAND.
WEATHER DRIES WITH A GRADUAL DECREASE IN CLOUDS WEDNESDAY NIGHT.
STRONGER WINDS AT THE SURFACE WILL BE INVOKED AHEAD OF THE NEXT
COLD FRONT AND AN INCREASING PRESSURE GRADIENT.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
A QUIET AND GRADUALLY TURNING COLDER PERIOD AS A SERIES OF COLD
FRONTS PASS THROUGH. FLURRIES OR LIGHT SNOW SHOWERS LOOK TO BE
THE ONLY PCPN UNTIL PERHAPS MON NIGHT INTO TUE. POTENTIALLY THE
COLDEST WEATHER OF THE WINTER ON TAP BY THE MIDDLE OF NEXT WEEK.
LONG WAVE TROUGH ACROSS THE EASTERN 2/3 OF THE CONUS GRADUALLY
DEEPENS INTO THE MIDDLE OF NEXT WEEK AS SHORTWAVE ENERGY ROTATES
INTO THE LONG WAVE AROUND A STRONG POLAR VORTEX OVER HUDSON BAY.
LONG WAVE TROUGH ACROSS THE EASTERN 2/3 OF THE CONUS GRADUALLY
DEEPENS OVER THE WEEKEND AND INTO EARLY NEXT WEEK AS THE UPPER
PATTERN AMPLIFIES. STRONG POLAR VORTEX OVER HUDSON BAY THU MORNING
WILL GRADUALLY WEAKEN AS IT TRACKS EASTWARD...KEEPING THE COLDEST
AIR ASSOCIATED WITH IT TO OUR NORTH. A SHORTWAVE TROUGH CURRENTLY
OVER ALASKA WILL DIVE THROUGH THE NW FLOW THROUGH WESTERN CANADA
AND THE NORTHERN PLAINS FRI AND SAT AIDING IN THE AMPLIFICATION OF
THE TROUGH OVER THE EASTERN US AND RIDGE OUT WEST. THIS ENERGY
ROUNDS THE BASE OF THE TROUGH IN THE GREAT LAKES AND MOVES THROUGH
THE OHIO VALLEY AND NEW ENGLAND SAT NIGHT AND SUN.
AT THE SFC...A COLD FRONT WILL TRACK ACROSS THE REGION THU EVE.
MODELS CONTINUE TO KEEP THE AREA DRY WITH ITS PASSAGE AND KEPT
CONSISTENCY WITH THE PREVIOUS FORECASTS THAT SUPPORT THIS IDEA.
H5 FLOW FLATTENS ON FRI WITH CLIPPER LOW PASSING WELL TO OUR
NORTH. HIGH PRES PASSES S OF THE LOCAL AREA FRI INTO SAT WITH FAIR
AND DRY WEATHER. IMPULSE DIVING OUT OF CENTRAL CANADA WILL RESULT
IN A CHANGE IN THE RECENT PATTERN. LOW PRES IS FORECAST TO TRACK
FROM THE GREAT LAKES THROUGH NORTHERN NEW ENGLAND DRAGGING A
STRONG COLD FRONT ACROSS THE AREA ON SUNDAY.
MEDIUM RANGE GUIDANCE BEGINS TO DIVERGE EARLY NEXT WEEK. THE ECMWF
INDICATES A FAIRLY POTENT SHORTWAVE DIVING FROM CENTRAL CANADA
INTO THE UPPER MISSISSIPPI VALLEY...WHILE THE GFS IS WEAKER. REST
OF THE GUIDANCE IS SPLIT WITH THE UKMET SIMILAR TO THE GFS AND THE
CMC SIMILAR TO THE EC. SINCE THE EC PERFORMS BETTER IN THE MEDIUM
RANGE...FOLLOWED HPC GUIDANCE CLOSELY BEYOND SUNDAY SINCE IT ALSO
INCORPORATES THE EC ENS MEAN.
TEMPS DROP TO SEASONABLE ON FRIDAY BEHIND THE COLD FRONT...THEN
REBOUND TO ABOVE NORMAL IN THE WAA ON SATURDAY. TEMPS FOR SUNDAY
ARE TRICKY DEPENDING ON TIMING OF THE COLD FROPA. BUT WILL
CERTAINLY FALL TO SLIGHTLY BELOW NORMAL ON MONDAY AND TUE.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
HIGH PRES MOVES OFFSHORE THIS EVENING...AND THEN LOW PRESSURE
APPROACHES FROM THE SOUTHWEST TONIGHT THROUGH WEDNESDAY.
VFR CONDS UNTIL THE ONSET OF PRECIPITATION AFTER 03Z. CONDS LOWER
TO MVFR...AND THEN QUICKLY TO IFR IN A MIXTURE OF RAIN AND SLEET
AT THE NYC METRO TERMINALS...A MIX OF RAIN SNOW AND SLEET FROM
KTEB TO KHPN TO KGON...AND ALL SNOW AT KSWF UNTIL WEDNESDAY
MORNING. A PERIOD OF FREEZING RAIN WILL BE POSSIBLE AT KSWF AFTER
13Z BEFORE CHANGING TO ALL RAIN. THERE COULD BE A PERIOD OF
FREEZING RAIN AS FAR SOUTH AS COASTAL CONNECTICUT HOWEVER
CONFIDENCE IS LOW AT THIS TIME.
IFR CONDS IN RAIN WILL CONTINUE THROUGH LATE WEDNESDAY AFTERNOON...
AND THEN CONDS IMPROVE TO VFR WEDNESDAY EVENING.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT: HTTP://WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KEWR FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED THROUGH
02Z. A MIX OF RAIN AND SLEET DEVELOPS AROUND 03Z A TENTH OF AN
INCH OF SLEET IS POSSIBLE. CONDITIONS BECOMING MVFR.
KJFK FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED THROUGH
02Z. A MIX OF RAIN AND SLEET DEVELOPS AROUND 03Z A TENTH OF AN
INCH OF SLEET IS POSSIBLE. CONDITIONS BECOMING MVFR.
KLGA FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED THROUGH
02Z. A MIX OF RAIN AND SLEET DEVELOPS AROUND 03Z A TENTH OF AN
INCH OF SLEET IS POSSIBLE. CONDITIONS BECOMING MVFR.
KTEB FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED THROUGH
02Z. A MIX OF SNOW AND SLEET DEVELOPS AROUND 03Z. UP TO AN INCH OF
SNOW AND SLEET IS POSSIBLE.
KHPN FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED THROUGH
02Z. A PERIOD OF SNOW DEVELOPS AROUND 03Z MIXING WITH SLEET AND
RAIN AFTER MIDNIGHT. UP TO 2 INCHES IF SNOW AND SLEET IS POSSIBLE.
KISP FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED. RAIN
DEVELOPS AFTER 03Z WITH MARGINAL CONDITIONS DEVELOPING.
.OUTLOOK FOR 00Z THURSDAY THROUGH SUNDAY...
.WEDNESDAY EVENING...BECOMING VFR EARLY.
.THURSDAY...VFR...W-NW GUSTY WINDS 10-15 G 25KTS.
.FRIDAY-SATURDAY...VFR.
.SUNDAY...MAINLY VFR. MVFR CONDS POSSIBLE WITH LIGHT PRECIPITATION
WITH COLD FRONTAL PASSAGE.
&&
.MARINE...
SUB SCA CONDITIONS EXPECTED THROUGH WEDNESDAY WITH INCREASING
NORTHEAST FLOW. NEXT CHANCE OF SCA CONDITIONS COMES WEDNESDAY
NIGHT WITH INCREASING PRESSURE GRADIENT AND WESTERLY FLOW.
SCA CONDS ARE POSSIBLE WED NIGHT AND THU IN RESPONSE TO THE
COMBINATION OF A TIGHT PRESSURE GRADIENT AND COLD AIR ADVECTION
BEHIND THE DEPARTING LOW. A WEAKENING COLD FRONT/TROUGH MOVES ACROSS
THE WATERS THU NIGHT WITH MARGINAL SCA CONDS POSSIBLE...MAINLY ON
THE OCEAN WATERS. SUB-ADVSY CONDS RETURN ON FRI WITH A WEAKENING
PRES GRADIENT AS HIGH PRES BUILDS INTO THE REGION. THE GRADIENT WILL
TIGHTEN ONCE AGAIN FRI NIGHT AND SAT AS HIGH PRES BUILDS TO THE S OF
THE AREA AND LOW PRES TRACKS WELL TO THE NORTH. SCA CONDS ARE
EXPECTED ONCE AGAIN. AFTER A BRIEF LULL SAT NIGHT INTO SUN...STRONG
SCA CONDS WILL RETURN YET AGAIN AS A STRONG COLD FRONT SWEEPS ACROSS
THE AREA.
&&
.HYDROLOGY...
QPF OF AROUND 0.4 TO 0.6 INCH LIQUID EQUIVALENT EXPECTED TONIGHT
INTO WED WITH HIGHER AMOUNTS NEAR THE COAST. MOST OF THIS SHOULD
FALL AS SNOW AWAY FROM THE IMMEDIATE CT COAST AND NYC METRO AREAS.
NO SIGNIFICANT PRECIPITATION IS EXPECTED THROUGH THE REMAINDER OF
THE WEEK.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 4 PM EST
WEDNESDAY FOR CTZ005>010.
NY...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 4 PM EST
WEDNESDAY FOR NYZ067>071.
NJ...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 4 PM EST
WEDNESDAY FOR NJZ002-004-103>105-107.
MARINE...NONE.
&&
$$
SYNOPSIS...24/JM
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...24
AVIATION...MPS
MARINE...24/JM
HYDROLOGY...24/JM
AREA FORECAST DISCUSSION
NWS NEW YORK NY
424 AM EST MON JAN 14 2013
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE REGION THIS MORNING AND THEN
BECOME STATIONARY TO OUR SOUTH TONIGHT THROUGH WEDNESDAY AS A
SERIES OF WEAK WAVES OF LOW PRESSURE RIDE ALONG IT. A COLD FRONT
CROSSES THE TRI-STATE ON THURSDAY WITH CANADIAN HIGH PRESSURE
BUILDING IN FOR THURSDAY NIGHT THROUGH SATURDAY. ANOTHER COLD FRONT
MOVES ACROSS THE TRI-STATE ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
COLD FRONT APPROACHING CENTRAL PA AS OF 08Z WITH TEXTBOOK WIND
SHIFT AND TEMP FALLS. AREA OF LIGHT RAIN OVER EASTERN PA RIDING
NORTH WILL PROVIDE MEASURABLE PCPN FOR NORTHWEST ZONES THROUGH
11Z BEFORE WEAKENING. 05Z HRRR RUN DEPICTS FRONT NICELY IN ITS
REFLECTIVITY FIELDS...THOUGH DO NOT EXPECT THIS TO PRODUCE MUCH
MORE THAN SPRINKLES. IN FACT...ONLY CHANCE POPS FOR MEASURABLE
PCPN AFTER 11Z OVER THE WESTERN TWO THIRDS OF THE REGION WITH
THE MAIN PCPN BEING SPOTTY LIGHT DRIZZLE/SPRINKLES. FRONT CLEARS
MONTAUK BY 18Z WITH FOG/DRIZZLE ALL ENDED BY NOON.
AS FOR FOG ADVISORY...HAVE SPLIT THAT UP FOR TIMING. I WAS GOING
THE CITY AND LONG ISLAND...BUT BASED ON LATEST LAMP GUIDANCE...HAVE
KEPT IT.
HAVE UNDER CUT MOS NUMBERS BASED PRIMARILY BASED ON 15 DEGREE DROP
SEEN ON WITH THE FROPA IN WESTERN PA AND EASTERN OH. DESPITE
THIS...STILL THINK WE CAN REACH THE LOWER 50S WITH DOWNSLOPE AND NORTHERLY
FLOW...THOUGH CONFIDENCE IS LOW AND WOULD NOT BE SHOCKED WITH A
BUST AND TEMPS STAYING IN THE 40S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
UNCERTAINTY CONTINUES TONIGHT AS MOISTURE SPREADS NORTHEAST ALONG
THE STALLED FRONT. OUR REGION IS ON THE NORTHERN EDGE OF THE PCPN
WITH THIS FEATURE. 00Z NAM AND WRF ARW SUPPORT A DRY SOLUTION
WITH GEM/GFS/WRF-ARW/AND MANY SREF MEMBERS SUPPORTING LGT PCPN
FOR THE SOUTHERN THIRD OF THE FCST AREA.
THERE IS AN IMPRESSIVE 170+KT SUBTROPICAL JET STREAK COMING OUT OF
TX WHICH PLACES THE REGION IN THE RIGHT FRONT QUADRANT THAT WOULD
HELP BUILD THE SFC HIGH AND AND BRING IN DRIER AIR. BUT THE NWP
QPF GUIDANCE CAN NOT BE IGNORED. HAVE THUS GONE WITH A TIGHT
GRADIENT OF POPS AND USED LIKELY FOR THE SOUTHERN PARTS OF THE
CITY AND LONG ISLAND.
THERMAL PROFILES SUPPORT SOME MIXING OF SLEET TO THE NORTH OF THE
CITY AND LONG ISLAND...BUT IMPACT IS EXPECTED TO BE MINIMAL IF THE
SLEET OCCURS AT ALL.
TONUGHT`S LOW TEMPS WERE A BLEND OF NAM AND GFS MOS WITH
ADJUSTMENTS UP DUE TO EXPECTED EXTENSIVE CLOUD COVER.
WEAK HIGH PRESSURE BUILDS IN BRIEFLY FOR TUESDAY. TEMPS WERE AGAIN
A BLEND OF MOS - NO ADJUSTMENTS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
INCREASING CONSENSUS AMONG THE MODELS THAT THE REGION WILL
EXPERIENCE LIGHT TO MODERATE PRECIPITATION TUESDAY NIGHT INTO
WEDNESDAY AS A WAVE OF LOW PRESSURE PASSES TO OUR SOUTH ALONG A
STALLED FRONTAL BOUNDARY. HAVE CHANCE POPS N AND LIKELY POPS S IN
THIS TIME FRAME. FOR NOW...BASED ON A BLEND OF NAM/GFS/ECMWF LOW
LEVEL THERMAL PROFILES - APPEARS WILL BE A MIX OF RAIN/SNOW/SLEET
ACROSS NYC/LONG ISLAND/MOST OF NE NJ CHANGING TO ALL RAIN WEDNESDAY
MORNING...AND A MIX OF SNOW/SLEET CHANGING TO ALL RAIN BEFORE ENDING
WEDNESDAY AFTERNOON. FOR NOW THINKING SUB-ADVISORY AMOUNTS ARE MOST
LIKELY...BUT THERE IS SOME POTENTIAL FOR ADVISORY LEVEL ACCUMULATION
ACROSS NORTHERN INTERIOR ZONES. WILL CONTINUE TO MONITOR.
USED A BLEND OF NAM/GFS MOS AND 2-METER TEMPERATURES FOR LOWS
TUESDAY NIGHT AND HIGHS WEDNESDAY...WITH LOWS BETWEEN...5 AND 10
DEGREES ABOVE NORMAL AND HIGHS A FEW DEGREES ABOVE NORMAL.
THE REGION WILL BE AT THE BASE OF A 500 HPA TROUGH ANCHORED WITH THE
POLAR VORTEX OVER HUDSON BAY WEDNESDAY NIGHT-THURSDAY NIGHT. THE
BASE OF THE TROUGH LIFTS FRIDAY WITH ZONAL FLOW GIVING WAY TO SW
FLOW/SLIGHT RIDGING ALOFT BY LATE SATURDAY. THE GFS IS FASTER THAN
THE ECMWF IN BRINGING IN THE NEXT RE-ENFORCING SHOT OF COLD AIR -
SATURDAY NIGHT VICE DURING THE DAY ON SUNDAY. HOWEVER...WITHOUT ANY
CLEAR INDICATION OF ONE MODEL BEING MORE RIGHT THAN THE OTHER...HAVE
OPTED FOR A GFS/ECMWF BLEND IN THIS TIME FRAME.
OTHER THAN POSSIBLY SOME FLURRIES UNDER THE COLD POOL
THURSDAY/THURSDAY NIGHT - NOT CONFIDENT ENOUGH IN THIS TO REFLECT IN
THE FORECAST AT THIS TIME...AND A SLIGHT CHANCE OF SNOW SHOWERS WITH
THE ARRIVAL OF THE COLD AIR SUNDAY OVER FAR W ZONES...IT APPEARS LOW
LEVELS WILL BE TOO DRY TO SUPPORT ANY PRECIPITATION WEDNESDAY
NIGHT-SUNDAY.
FOR TEMPERATURES WEDNESDAY NIGHT-SUNDAY USED A BLEND OF MEX/MEX
ENSEMBLE MEAN/ECE/HPC GUIDANCE. TEMPERATURES TREND FROM 5-10 DEGREES
ABOVE NORMAL AT THE START OF THIS TIME FRAME TO SLIGHTLY BELOW
NORMAL ON FRIDAY...THEN REBOUND TO A TAD ABOVE NORMAL FOR THE
WEEKEND. DEPENDING ON EXACTLY WHEN THE COLD AIR MOVES IN
SUNDAY...COULD END UP BEING BELOW NORMAL THEN...BUT TOO MUCH
UNCERTAINTY TO FORECAST THAT AT THIS TIME.
&&
.AVIATION /09Z MONDAY THROUGH FRIDAY/...
A COLD FRONT APPROACHES EARLY THIS MORNING...AND PASSES THROUGH AFTER
DAYBREAK. HIGH PRESSURE GRADUALLY BUILDS INTO THE REGION FROM THE
WEST THROUGH TONIGHT.
ABUNDANT LOW-LEVEL MOISTURE AND LIGHT WINDS AHEAD OF AN APPROACHING
COLD FRONT HAVE RESULTED WIDESPREAD LIFR OR LOWER CONDITIONS IN
STRATUS/FOG/DZ. MODERATE TO HIGH CONFIDENCE IN THIS CONTINUING TILL
DAYBREAK...HOWEVER THERE MAY BE BRIEF PERIODS OF CHANGING CONDITIONS.
CONDITIONS EXPECTED TO IMPROVE A BIT TOWARDS DAYBREAK...PARTICULARLY
ACROSS THE NYC/NJ METRO TERMINALS WHERE SW WINDS AT 1-2 KFT INCREASE
TO 30-40 KT. THIS MIGHT PROMOTE ENOUGH TURBULENT MIXING TO SLIGHTLY
IMPROVED VSBY/CIGS TO IFR. IN ADDITION...THERE COULD BE SOME
MARGINAL LOW LEVEL WIND SHEAR ISSUES.
COLD FRONT WILL PUSH ACROSS THE REGION JUST AFTER DAYBREAK...WITH
CONDITIONS SLOWLY IMPROVING AT FIRST...THEN VSBY QUICKLY BECOMING
VFR AROUND 15Z-16Z. TIMING OF LIFR/IFR CIGS IMPROVEMENT COULD BE OFF
BY AN HOUR OR SO DEPENDING ON STRENGTH OF DRY AIR ADVECTION BEHIND
THE FRONT.
HIGH CONFIDENCE IN VFR BY THIS AFTERNOON. NW WINDS 10-15G20KT
EXPECTED...MAINLY RIGHT OF 310 MAGNETIC.
WINDS GRADUALLY WEAKEN THIS EVENING AND VEER N. A WEAK WAVE RIDING
TO THE SOUTH WILL LIKELY RESULT IN INCREASING HIGH/MID CLOUDS THIS
EVENING...WITH A FEW SHOWERS POSSIBLE AFTER MIDNIGHT ACROSS
SOUTHERN TERMINALS.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP://WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KEWR FCSTER COMMENTS: AMENDMENTS EXPECTED THIS MORNING FOR CHANGING
FLIGHT CATEGORIES - VARIABLE CIGS AND VSBYS.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KJFK FCSTER COMMENTS: AMENDMENTS EXPECTED THIS MORNING FOR CHANGING
FLIGHT CATEGORIES - VARIABLE CIGS AND VSBYS.
KLGA FCSTER COMMENTS: AMENDMENTS EXPECTED THIS MORNING FOR CHANGING
FLIGHT CATEGORIES - VARIABLE CIGS AND VSBYS.
KTEB FCSTER COMMENTS: AMENDMENTS EXPECTED THIS MORNING FOR CHANGING
FLIGHT CATEGORIES - VARIABLE CIGS AND VSBYS.
KHPN FCSTER COMMENTS: MEDIUM TO HIGH CONFIDENCE OF LIFR OR LESS
UNTIL 13Z...THEN GRADUAL IMPROVEMENT EXPECTED.
KISP FCSTER COMMENTS: MEDIUM TO HIGH CONFIDENCE OF LIFR OR LESS
UNTIL 13Z...THEN GRADUAL IMPROVEMENT EXPECTED.
.OUTLOOK FOR 06Z TUE THROUGH FRI...
.LATE TONIGHT-TUE MORNING...LOW PROB FOR MVFR CONDS...ESPECIALLY
LATE TONIGHT FOR NYC METRO AND LONG ISLAND...AS WEAK LOW PRESSURE
PASSES TO THE SOUTH. PCPN TYPE SHOULD BE MOSTLY RAIN...BUT SOME
SNOW COULD MIX IN.
.TUE AFTERNOON/EVENING...VFR.
.LATE TUE NIGHT-WED MORNING...SLIGHT CHANCE FOR MVFR CONDS FOR NYC
METRO AND LONG ISLAND...AS ANOTHER WEAK LOW PASSES TO THE SOUTH.
.WED AFTERNOON-FRI...VFR. COLD FROPA THU EVENING...FOLLOWED BY
GUSTY NW WINDS THU NIGHT-FRI.
&&
.MARINE...
THE DENSE FOG ADVISORY REMAINS UP THROUGH THE MORNING.
COLD FRONT PASSES MID TO LATE MORNING AND WHILE THERE MAY BE A
GUST TO THE MID 20S...THIS WOULD ONLY BE WITH THE FRONT ITSELF.
SEAS IN A SE SWELL ARE AROUND 4 FEET ON THE OCEAN AT MOST...THUS
THE SMALL CRAFT ADVISORY FOR THE OCEAN HAS BEEN DROPPED.
A LIGHT PRESSURE GRADIENT ACROSS THE REGION WILL PROMOTE WINDS 10 KT
OR LESS TUESDAY INTO WEDNESDAY. STRONG COLD ADVECTION WILL SEE
SMALL CRAFT CONDITIONS AND POSSIBLY GALE FORCE GUSTS ON ALL WATERS
WEDNESDAY NIGHT AND POSSIBLY INTO THURSDAY. SUB-SMALL CRAFT
CONDITIONS SHOULD RETURN TO ALL WATERS BY FRIDAY.
&&
.HYDROLOGY...
LIGHT PCPN IS EXPECT THIS MORNING AND AGAIN OVERNIGHT. A 1/4 OF
AN INCH OF LIQUID EQUIVALENT...AND POSSIBLY A BIT MORE OVER LONG
ISLAND AND NYC...IS EXPECTED OVER THE REGION TUESDAY NIGHT AND
WEDNESDAY.
NO HYDROLOGIC IMPACTS ARE EXPECTED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR CTZ006>008-
010>012.
DENSE FOG ADVISORY UNTIL 8 AM EST THIS MORNING FOR CTZ005-009.
NY...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR NYZ078>081-
177-179.
DENSE FOG ADVISORY UNTIL 8 AM EST THIS MORNING FOR NYZ067>075-
176-178.
NJ...DENSE FOG ADVISORY UNTIL 8 AM EST THIS MORNING FOR NJZ002-004-
006-103>108.
MARINE...DENSE FOG ADVISORY UNTIL NOON EST TODAY FOR ANZ330-335-338-340-
345-350-353-355.
&&
$$
SYNOPSIS...TONGUE
NEAR TERM...TONGUE
SHORT TERM...TONGUE
LONG TERM...MALOIT
AVIATION...BC/NV
MARINE...MALOIT/TONGUE
HYDROLOGY...TONGUE
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1259 AM EST MON JAN 14 2013
.SYNOPSIS...
A COLD FRONT OVER WESTERN PENNSYLVANIA APPROACHES OVERNIGHT. THE
FRONT MOVES SOUTH AND EAST BY AFTERNOON AND THEN BECOMES
STATIONARY TO OUR SOUTH TONIGHT THROUGH WEDNESDAY WITH A SERIES
OF WEAK WAVES OF LOW PRESSURE RIDING ALONG IT. HIGH PRESSURE
RETURNS ON THURSDAY...FOLLOWED BY A COLD FRONT PASSING THROUGH
THURSDAY NIGHT. HIGH PRESSURE THEN REMAINS IN CONTROL INTO THE END
OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
FRONT IS NEARING KPIT AS OF 0530Z AND IS ACCELERATING WITH G30
KT IN IT`S WAKE. THUS ARRIVAL IN THE WESTERN THIRD OF THE CWA BY
SUNRISE SEEMS LIKELY. WILL CONTINUE THE DENSE FOG ADVISORY AND
HAVE MADE THE DRIZZLE PERSISTENT. VSBYS ARE FLUCTUATING UP TO 3
MILES AT KEWR...BUT WILL NOT TRY TO CHASE THINGS WITH MOS STILL
SUGGESTING LOWERING TOWARDS SUNRISE.
PCPN WITH THE FRONT DIMINISHES AS IT APPROACHES PER ALL LATEST
NWP. HRRR DOES HAVE BAND OF LIGHT PCPN MAKING TO THE CT/LONG
ISLAND AREAS...BUT BELIEVE THIS IS OVER DONE. DRIZZLE IS THE MAIN
PCPN PRODUCER.
WARM ADVECTION ALOFT WILL CONTINUE TO SUPPORT DRIZZLE AND FOG
UNTIL THE FRONT DOES PASS WITH STEADY TEMPS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
COLD FRONT PUSHES DRIZZLE...FOG AND ANY LIGHT RAIN OUT OF THE
REGION BY NOON FROM NORTHWEST TO SOUTHEAST. CLEARING BY MIDDAY. A
GUSTY NW FLOW ON THE BACKSIDE THIS AFTN.
HIGHS WILL GET UP TO AROUND 50 INLAND...AND THE LOW TO MID 50S AT
THE COAST. THE STRONGEST COLD ADVECTION FOLLOWS IN THE AFT/EVE...
WHICH ALLOWS THE AIR MASS TO WARM UP WELL ABOVE SEASONABLE LEVELS.
GUSTS IN THE AFT WILL BE UP TO 20 MPH.
A WEAK WAVE OF LOW PRESSURE PASSES WELL SOUTH AND EAST LATE MON
NIGHT WITH SOME LIGHT PCPN...MAINLY NEAR THE COAST...BUT HAVE
PUSHED BACK THE TIMING TO AFT 9 PM. AS THE COLD AIR FILTERS
IN...ANY PCPN THAT DOES FALL MAY MIX WITH SOME SLEET OR SNOW. NO
ACCUM IS EXPECTED. THERE COULD HOWEVER BE A FEW SLICKS SPOTS FOR
THE MORNING COMMUTE TUE.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
MOISTURE SHIFTS TO THE SOUTH THROUGH TUESDAY. THIS IS IN ASSOCIATION
WITH A STALLING FRONTAL BOUNDARY TO OUR SOUTH. THEREFORE...ONLY A
SLIGHT CHANCE OF PCPN OVER THE LAND AREAS DURING THE
MORNING...THEN DRY IN THE AFTERNOON. AS FOR PCPN TYPE...BY
DAYBREAK ON TUESDAY...A WARM NOSE ALOFT ERODES AND WOULD LIKELY
SUPPORT EITHER SNOW...SLEET OR A MIXTURE OF THE TWO. THEN BY LATE
MORNING...THE BOUNDARY LAYER WOULD WARM UP ENOUGH FOR RAIN BEING
MIXED WITH THE WINTRY PCPN. IN ANY CASE...POPS AND QPF ARE LOW.
HIGH TEMPERATURES STILL END UP A LITTLE ABOVE NORMAL.
A WAVE OF LOW PRESSURE THEN MOVES ALONG THE FRONTAL BOUNDARY TUESDAY
NIGHT INTO WEDNESDAY...BUT AGAIN...ONLY A LOW CHANCE OF PCPN...AND
FOCUSED LATE AT NIGHT INTO WEDNESDAY MORNING. SNOW WOULD BE THE MOST
LIKELY PCPN TYPE UNTIL MID-MORNING...THEN EVENTUALLY A CHANGE TO
RAIN BY THE AFTERNOON IF THERE`S ANY LINGERING PCPN.
FOR THURSDAY...A COLD FRONT PASSES THROUGH IN THE EVENING. MAYBE A
SPRINKLE IN THE AFTERNOON...THEN A SPRINKLE OR FLURRY IN THE
EVENING. HIGH PRESSURE OTHERWISE REMAINS THE DOMINANT FEATURE FOR
OUR WEATHER THROUGH THE UPCOMING WEEKEND. A COLD FRONT COULD BRING
PCPN OUR WAY ON SUNDAY...BUT WILL GO WITH A DRY FORECAST FOR NOW
AS MOISTURE APPEARS TO BE LACKING.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
A COLD FRONT APPROACHES EARLY THIS MORNING...AND PASSES THROUGH AFTER
DAYBREAK. HIGH PRESSURE GRADUALLY BUILDS INTO THE REGION FROM THE
WEST THROUGH TONIGHT.
ABUNDANT LOW-LEVEL MOISTURE AND LIGHT WINDS AHEAD OF AN APPROACHING
COLD FRONT HAVE RESULTED IN THE RE-DEVELOPMENT OF WIDESPREAD LIFR OR
LOWER CONDS IN STRATUS/FOG/DZ. MODERATE TO HIGH CONFIDENCE IN THIS
CONTINUING TILL DAYBREAK. THERE IS SOME UNCERTAINTY IF THESE CONDS
IMPROVE A BIT TOWARDS DAYBREAK THOUGH...PARTICULARLY NYC/NJ METRO
TERMINALS AS SW WINDS AT 1-2 KFT INCREASE TO 30-40 KT. THIS MIGHT
PROMOTE ENOUGH TURBULENT MIXING TO SLIGHTLY IMPROVED VSBY/CIGS TO
IFR. IN ADDITION...THERE COULD BE SOME MARGINAL LOW LEVEL WIND
SHEAR ISSUES.
COLD FROPA STILL EXPECTED JUST AFTER DAYBREAK...WITH CONDS SLOWLY
IMPROVING AT FIRST...THEN VSBY QUICKLY BECOMING VFR AFTER ABOUT
15Z-16Z. TIMING OF LIFR/IFR CIGS IMPROVEMENT COULD BE OFF BY AN HOUR
OR SO DEPENDING ON STRENGTH OF DRY AIR ADVECTION BEHIND THE FRONT.
HIGH CONFIDENCE IN VFR BY THIS AFTERNOON. NW WINDS
10-15G20KT EXPECTED...MAINLY RIGHT OF 310 MAGNETIC.
WINDS GRADUALLY WEAKEN THIS EVENING AND VEER N. A WEAK WAVE RIDING
TO THE SOUTH WILL LIKELY RESULT IN INCREASING HIGH/MID CLOUDS THIS
EVENING...WITH A FEW SHOWERS POSSIBLE AFTER MIDNIGHT ACROSS
SOUTHERN TERMINALS.
.OUTLOOK FOR 06Z TUE THROUGH FRI...
.LATE TONIGHT-TUE MORNING...LOW PROB FOR MVFR CONDS...ESPECIALLY
LATE TONIGHT FOR NYC METRO AND LONG ISLAND...AS WEAK LOW PRESSURE
PASSES TO THE SOUTH. PCPN TYPE SHOULD BE MOSTLY RAIN...BUT SOME
SNOW COULD MIX IN.
.TUE AFTERNOON/EVENING...VFR.
.LATE TUE NIGHT-WED MORNING...SLIGHT CHANCE FOR MVFR CONDS FOR NYC
METRO AND LONG ISLAND...AS ANOTHER WEAK LOW PASSES TO THE SOUTH.
.WED AFTERNOON-FRI...VFR. COLD FROPA THU EVENING...FOLLOWED BY
GUSTY NW WINDS THU NIGHT-FRI.
&&
.MARINE...
THE DENSE FOG ADVISORY REMAINS UP THROUGH THE NIGHT FOR
VISIBILITIES 1 NM OR LESS.
WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW ADVISORY CRITERIA
THROUGH THE OVERNIGHT.
WINDS PRECEDING A COLD FRONTAL PASSAGE IN THE MORNING WILL PRODUCE
MARGINAL SCA WINDS AND SEAS ACROSS THE OCEAN WATERS EAST OF FIRE
ISLAND INLET. CONFIDENCE IN THIS SCENARIO IS WANING AND IT IS
QUITE POSSIBLE THAT SCA CONDITIONS ARE NOT MET. A GUSTY NW FLOW MON
AFT/ERLY EVE WILL GET UP TO AROUND 20 KT BEFORE DIMINISHING LATE
AS HIGH PRESSURE NOSES IN FROM THE OHIO VALLEY.
RELATIVELY TRANQUIL CONDITIONS PREVAIL ON TUESDAY AND WEDNESDAY.
SCA CONDITIONS THEN BECOME POSSIBLE AGAIN WEDNESDAY NIGHT...AND
MORE LIKELY DURING THURSDAY AS THE PRESSURE GRADIENT TIGHTENS
AHEAD OF A COLD FRONT...CAUSING WINDS AND SEAS TO INCREASE. THE
COLD FRONT MOVES THROUGH THURSDAY NIGHT...WITH SUB SCA CONDITIONS
PROBABLE ACROSS ALL WATERS BY FRIDAY AFTERNOON.
&&
.HYDROLOGY...
THERE IS ONLY POTENTIAL FOR LIGHT PRECIPITATION AMOUNTS THROUGH THE
FORECAST PERIOD.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...DENSE FOG ADVISORY UNTIL 7 AM EST THIS MORNING FOR CTZ005>012.
NY...DENSE FOG ADVISORY UNTIL 7 AM EST THIS MORNING FOR NYZ067>075-
078>081-176>179.
NJ...DENSE FOG ADVISORY UNTIL 7 AM EST THIS MORNING FOR NJZ002-004-
006-103>108.
MARINE...DENSE FOG ADVISORY UNTIL 7 AM EST THIS MORNING FOR ANZ330-335-
338-340-345-350-353-355.
SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 6 PM EST THIS
EVENING FOR ANZ350-353.
&&
$$
SYNOPSIS...JC/DW
NEAR TERM...JC/TONGUE/DW
SHORT TERM...TONGUE/DW
LONG TERM...JC
AVIATION...NV
MARINE...JC/DW
HYDROLOGY...JC/DW
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
150 PM EST MON JAN 14 2013
.SYNOPSIS (REST OF TODAY THROUGH TUESDAY)...
18Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A CONTINUED HIGHLY
AMPLIFIED UPPER LEVEL PATTERN IN PLACE ACROSS THE CONUS. PATTERN IS
DOMINATED BY A LARGE AND IMPRESSIVE LONGWAVE TROUGH COVERING ALMOST
THE ENTIRE CONUS. THE LAST DOMAIN OF THE ONCE PROMINENT UPPER RIDGE
ALONG THE EAST COAST IS ACROSS THE FAR SOUTHEASTERN STATES.
LUCKILY...THIS INCLUDES US AND WILL ALLOW OUR GENERALLY DRY AND WARM
WEATHER TO CONTINUE FOR ANOTHER COUPLE OF DAYS.
UPPER LEVEL JET AND HIGH LEVEL MOISTURE AXIS IS LOCATED WELL OFF TO
OUR NORTHWEST THIS AFTERNOON...AND HENCE WE ARE NOT SEEING THE HIGH
LEVEL CIRRUS COMPARED TO WHAT OCCURRED ON SUNDAY. HOWEVER...SIMILAR
TO PREVIOUS DAYS...WE HAVE SEEN THE DEVELOPMENT OF A SCT-BKN SHALLOW
CU FIELD WITHIN THE SOUTHEAST LOW LEVEL FLOW.
&&
.SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...
TONIGHT THROUGH TUESDAY NIGHT...
MORE OF THE SAME FOR TONIGHT INTO TUESDAY AS THE STACKED RIDGING
HOLDS ON JUST A LITTLE BIT LONGER. STATIC SYNOPTIC PATTERNS
GENERALLY YIELD STATIC WEATHER. THIS FORECAST WILL REFLECT THAT
PHILOSOPHY WITH SOME PATCHY FOG AND LOW CLOUDS DURING THE LATE NIGHT
/ EARLY MORNING HOURS OF TUESDAY...THEN HAVING ANY FOG BURN OFF BY
AROUND 900 AM. AFTERNOON TEMPS WILL CLIMB TO WITHIN A FEW DEGREES OF
80 INLAND...AND A FEW DEGREES COOLER AT THE BEACHES WITH AN ONSHORE
AFTERNOON BREEZE. AREAS OF EARLY MORNING LOW CLOUDS WILL BURN OFF
QUICKLY AND BE REPLACED A FEW HOURS LATER BY ANOTHER SCT-BKN LOW
LEVEL CU FIELD.
WEDNESDAY/WEDNESDAY NIGHT...
THE APPROACH OF A SERIES OF UPPER LEVEL IMPULSES WILL FINALLY BEGIN
TO PUSH THE UPPER RIDGE TO THE EAST OF THE REGION LATER WEDNESDAY
AND WEDNESDAY NIGHT ALONG WITH A SLOW WEAKENING OF THE SURFACE
RIDGE. OVERALL THE WEATHER FOR WEDNESDAY WILL STILL BE GENERALLY
FAIR AND WARM...BUT CHANGES TO THIS STATIC PATTERN WILL NOT BE FAR
AWAY...AND BE ON THE APPROACH. INITIAL PUSH SYNOPTIC PUSH ON
WEDNESDAY WILL FAIL TO PUSH THE FRONT THROUGH OUR REGION...AND WILL
STALL IT JUST TO OUR NORTH. THE NEXT STRONGER PIECE OF ENERGY MOVING
ALONG THE NORTHERN GULF COAST WILL HOWEVER DO THE TRICK AND PROPEL
THE BOUNDARY THROUGH THE AREA THURSDAY AND/OR THURSDAY NIGHT.
&&
.LONG TERM (THURSDAY THROUGH SUNDAY)...
U/L LOW OVER THE SOUTHERN PLAINS WILL OPEN UP AND LIFT NORTHEAST
ACROSS THE LOWER MISSISSIPPI VALLEY AND SOUTHEAST U.S. THURSDAY. AN
ASSOCIATED COLD FRONT WILL PUSH EAST AND APPROACH WEST CENTRAL
FLORIDA LATE THURSDAY AND THURSDAY NIGHT. MAIN U/L ENERGY WILL
REMAIN WELL NORTH OF THE REGION WITH ONLY A CHANCE OF SHOWERS WITH
THE FRONT. COOLER AIR WILL ADVECT OVER THE FORECAST AREA THURSDAY
NIGHT AND FRIDAY. THE COLD FRONT WILL STALL ACROSS SOUTH FLORIDA AS
IT BECOMES PARALLEL TO THE U/L FLOW FRIDAY AND FRIDAY NIGHT. THIS
WILL KEEP SKIES MOSTLY CLOUDY ACROSS THE REGION WITH A SLIGHT CHANCE
OF A SHOWER. THE FRONT WILL GRADUALLY RETURN NORTH AS A WARM FRONT
SATURDAY WITH A WEAK SURFACE LOW POSSIBLY DEVELOPING ALONG THE
FRONTAL BOUNDARY EAST OF FLORIDA SUNDAY. THIS WILL CONTINUE THE
MOSTLY CLOUDY SKIES AND A SLIGHT CHANCE OF SHOWERS INTO EARLY
SATURDAY...WITH DECREASING CLOUDINESS SATURDAY AS THE SURFACE LOW
LIFTS NORTHEAST OF THE AREA.
&&
.AVIATION...
VFR FOR THE REST OF TODAY WITH SOME LOCAL CEILINGS AROUND 4000 FEET
AT TIMES. FOG DEVELOPS AGAIN OVERNIGHT BUT THINK MOST TERMINALS STAY
VFR. SOME IFR OR EVEN LIFR POSSIBLE 09Z TO 13Z TUESDAY AT PGD AND
LAL.
&&
.MARINE...
HIGH PRESSURE NORTH OF THE BAHAMAS WILL CONTINUE TO RIDGE BACK TO
THE WEST ACROSS THE FLORIDA PENINSULA AND EASTERN GULF OF MEXICO
THROUGH WEDNESDAY. A COLD FRONT WILL THEN CROSS THE FORECAST WATERS
DURING THURSDAY WITH A WIND SHIFT TO THE NORTH IN ITS WAKE BY
THURSDAY NIGHT AND FRIDAY. A PERIOD OF CAUTIONARY TO ADVISORY LEVEL
WINDS AND SEAS WILL ALSO BE POSSIBLE IN THE WAKE OF THIS FRONT.
&&
.FIRE WEATHER...
HIGH PRESSURE WILL CONTINUE TO DOMINATE THE LOCAL WEATHER THROUGH
THE MIDDLE OF THE WEEK. DAYTIME HIGH TEMPERATURES WILL REMAIN ABOVE
NORMAL...HOWEVER PLENTY OF LOW LEVEL MOISTURE WILL PREVENT ANY
SIGNIFICANT FIRE WEATHER CONCERNS. A COLD FRONT WILL CROSS THE AREA
LATE IN THE WEEK WITH CHANCES FOR A FEW SHOWERS AND FOLLOWED BY A
MORE SEASONABLE AIRMASS BY THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 64 79 64 78 / 0 0 0 0
FMY 62 81 62 82 / 0 0 0 10
GIF 57 81 58 82 / 0 0 0 0
SRQ 61 78 59 77 / 0 0 0 0
BKV 54 80 54 81 / 0 0 0 10
SPG 65 77 64 78 / 0 0 0 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/MARINE/FIRE WX...MROCZKA
AVIATION...JILLSON
LONG TERM...OGLESBY
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
1045 AM EST MON JAN 14 2013
.UPDATE (REST OF TODAY THROUGH TUESDAY)...
15Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A CONTINUED HIGHLY
AMPLIFIED UPPER LEVEL PATTERN IN PLACE ACROSS THE CONUS. PATTERN IS
DOMINATED BY A LARGE AND IMPRESSIVE LONGWAVE TROUGH COVERING ALMOST
THE ENTIRE CONUS. THE LAST DOMAIN OF THE ONCE PROMINENT UPPER RIDGE
ALONG THE EAST COAST IS ACROSS THE FAR SOUTHEASTERN STATES.
LUCKILY...THIS INCLUDES US AND WILL ALLOW OUR GENERALLY DRY AND WARM
WEATHER TO CONTINUE FOR ANOTHER COUPLE OF DAYS.
UPPER LEVEL JET AND HIGH LEVEL MOISTURE AXIS IS LOCATED WELL OFF TO
OUR NORTHWEST TODAY...AND HENCE WE SHOULD SEE MUCH LESS IN THE WAY
OF HIGH LEVEL CIRRUS COMPARED TO WHAT OCCURRED ON SUNDAY.
HOWEVER...SIMILAR TO PREVIOUS DAYS...WE WILL SEE THE DEVELOPMENT OF
A SCT-BKN SHALLOW CU FIELD WITHIN THE SOUTHEAST LOW LEVEL FLOW BY
THE EARLY AFTERNOON HOURS.
MORNING SOUNDINGS HAVE A VERY SIMILAR MID/LOW LEVEL PROFILE THE PAST
FEW DAYS...AND THAT PATTERN CONTINUES THIS MORNING WITH A
WELL-DEFINED SUBSIDENCE INVERSION AROUND 850MB UNDERNEATH THE
SUPPRESSION OF THE UPPER RIDGE. EXPECT DIURNAL MIXING BY LATE
AFTERNOON UP TO AROUND 5000 FEET AND WITH 850MB TEMPS IN THE 14-15C
RANGE...THIS SHOULD MIX OUT NICELY TO HIGH TEMPS IN THE LOWER 80S
AWAY FROM THE IMMEDIATE COAST. THE WEAK GRADIENT AND STRONG LAND
BASED HEATING SHOULD BE ENOUGH TO TURN WINDS ONSHORE AT THE BEACHES
DURING THE AFTERNOON WITH FEEBLE SEA-BREEZE DEVELOPMENT. MOST OF THE
HIRES GUIDANCE IS SHOWING THIS WIND SHIFT BY 19-20Z...AND THIS
SHOULD KEEP THE IMMEDIATE COAST A FEW DEGREES COOLER.
MORE OF THE SAME FOR TONIGHT INTO TUESDAY AS THE STACKED RIDGING
HOLDS ON JUST A LITTLE BIT LONGER. STATIC SYNOPTIC PATTERNS
GENERALLY YIELD STATIC WEATHER. THIS FORECAST WILL REFLECT THAT
PHILOSOPHY WITH SOME PATCHY FOG AND LOW CLOUDS DURING THE LATE NIGHT
/ EARLY MORNING HOURS OF TUESDAY...THEN HAVING ANY FOG BURN OFF BY
AROUND 900 AM. AFTERNOON TEMPS WILL CLIMB TO WITHIN A FEW DEGREES OF
80 INLAND...AND A FEW DEGREES COOLER AT THE BEACHES WITH AN ONSHORE
AFTERNOON BREEZE. ENJOY!
&&
.AVIATION...
MORNING FOG JUST ABOUT GONE WITH MAINLY VFR REST OF THE DAY. PATCHY
FOG POSSIBLE AGAIN TONIGHT WITH MAIN IMPACTS EXPECTED AT PGD.
&&
.MARINE...
HIGH PRESSURE NORTH OF THE BAHAMAS WILL CONTINUE TO RIDGE BACK TO
THE WEST ACROSS THE FLORIDA PENINSULA AND EASTERN GULF OF MEXICO
THROUGH WEDNESDAY. A COLD FRONT WILL THEN CROSS THE FORECAST WATERS
DURING THURSDAY WITH A WIND SHIFT TO THE NORTH IN ITS WAKE BY
THURSDAY NIGHT AND FRIDAY. A PERIOD OF CAUTIONARY TO ADVISORY LEVEL
WINDS AND SEAS WILL ALSO BE POSSIBLE IN THE WAKE OF THIS FRONT.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 80 63 78 62 / 0 0 05 05
FMY 80 63 80 62 / 0 0 05 05
GIF 80 59 81 59 / 0 0 05 05
SRQ 78 60 77 61 / 0 0 05 05
BKV 81 53 81 55 / 0 0 05 05
SPG 78 64 76 65 / 0 0 05 05
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/MARINE...MROCZKA
AVIATION...JILLSON
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
951 PM EST TUE JAN 15 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 212 PM EST TUE JAN 15 2013
QUIET WEATHER CAN BE EXPECTED UNDER HIGH PRESSURE THROUGH THE END
OF THE WEEK WITH TEMPERATURES NEAR NORMAL FOR THIS TIME OF YEAR.
COULD SEE A BRIEF WARM UP SATURDAY INTO THE 40S BEFORE
TEMPERATURES DROP BACK TO NORMAL SUNDAY AND THEN GET VERY COLD TO
START OUT THE WEEK. A CLIPPER SYSTEM WILL MOVE THROUGH SUNDAY
NIGHT THROUGH MONDAY NIGHT BRINGING CHANCES FOR SNOW.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 929 PM EST TUE JAN 15 2013
LATEST SHORT TERM MODEL GUIDANCE ALONG WITH REGIONAL RADAR LOOPS
SUGGEST PRECIPITATION SHIELD ASSOCIATED WITH SYSTEM MOVING THROUGH
THE TENNESSEE VALLEY SHOULD STAY SOUTH OF THE FORECAST AREA TONIGHT
FOR THE MOST PART. ONLY HAVE SLIGHT CHANCE POPS GOING OVER THE FAR
SOUTHEAST FOR THE REST OF THE NIGHT...SO WILL LEAVE THE POP FORECAST
AS IS.
THIS EVENING/S UPPER AIR INDICATE TEMPERATURES NEAR OR BELOW
FREEZING THROUGHOUT THE COLUMN THIS FAR NORTH...SO THINK THE CHANCES
OF FREEZING RAIN THIS FAR NORTH ARE DIMINISHING.
FINALLY...WITH ONLY WEAK COLD ADVECTION TONIGHT AND SKIES REMAINING
CLOUDY MOST OF THE NIGHT...DECIDED TO BUMP UP THE LOWS A COUPLE OF
DEGREES.
PREVIOUS DISCUSSION FOLLOWS.
SKIES SHOULD START OUT MOSTLY CLOUDY WITH A LOW PRESSURE SYSTEM
MOVING NORTHEAST OUT OF THE GULF AND THROUGH THE SOUTHEASTERN U.S. A
BIT OF MODEL DISAGREEMENT OVER HOW FAR NORTH PRECIPITATION
ASSOCIATED WITH THIS SYSTEM WILL GET DESPITE SIMILAR POSITIONS AND
STRENGTH FOR THE LOW PRESSURE CENTER. THE RAP AND GEM WERE THE
FURTHEST NORTH AND BRING THE PRECIP INTO THE FAR SOUTHEASTERN
COUNTIES. THE GFS KEEPS THE PRECIP WELL TO THE SOUTH...WHILE THE NAM
AND 0Z ECMWF JUST CLIP THE FAR SOUTHEAST WITH A HUNDREDTH OF QPF.
WITH THE VARIETY OF SOLUTIONS SHOULD CARRY A LOW CHANCE POP IN THE
FAR SOUTHEAST WITH DRY WEATHER BUT MOSTLY CLOUDY SKIES ELSEWHERE.
WENT WITH LOWS A DEGREE OR TWO BELOW GUIDANCE WITH EXPECTED COLD
ADVECTION.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
ISSUED AT 212 PM EST TUE JAN 15 2013
HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH THE SHORT TERM. A
LOW PRESSURE SYSTEM MOVING ACROSS THE HUDSON BAY WILL DRAG A COLD
FRONT ACROSS THE GREAT LAKES WEDNESDAY AND WEDNESDAY NIGHT...BUT IT LOOKS
LIKE ALL THE FORCING ASSOCIATED WITH IT WILL STAY WELL NORTH OF THE
AREA. ANOTHER SOUTHERN LOW PRESSURE SYSTEM WHICH WILL MOVE ACROSS
THE SOUTHEAST U.S. DURING THE SAME TIME APPEARS TO BE TOO FAR SOUTH
TO IMPACT POPS HERE. GUIDANCE IS IN GOOD AGREEMENT AND WILL USE AN
AVERAGE WHICH RESULTS IN NEAR NORMAL TEMPERATURES AND DRY WEATHER.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ISSUED AT 248 PM EST TUE JAN 15 2013
FOCUS OF THE EXTENDED PERIOD REMAINS ON THE ARRIVAL OF WHAT
INCREASINGLY APPEARS TO BE THE COLDEST AIRMASS OF THE SEASON AS A
PIEICE OF THE POLAR VORTEX BREAKS OFF AND AMPLIFIES THE UPPER
TROUGH OVER THE EASTERN PART OF THE COUNTRY.
WARMEST DAY OF THE PERIOD WILL BE SATURDAY AS SOUTHERLY FLOW AHEAD
OF A COLD FRONT ENABLES TEMPS TO RISE INTO THE 40S ACROSS THE
FORECAST AREA. LOW PRESSURE WILL TRACK THROUGH THE GREAT LAKES
SATURDAY NIGHT AND BRING THE COLD FRONT THROUGH CENTRAL INDIANA BY
EARLY SUNDAY. THE FRONT WILL USHER IN THE INITIAL SHOT OF COLDER
AIR...AS TEMPS ARE LIKELY TO FALL BACK INTO THE 20S AND LOWER 30S.
PASSAGE OF THE FRONT LOOKS TO BE DRY AS DEEPER MOISTURE IS FOCUSED
CLOSER TO THE LOW ACROSS THE GREAT LAKES. ARCTIC FRONT SET TO DIVE
INTO THE REGION ON MONDAY...USHERING IN MUCH COLDER AIR AS 850MB
TEMPS NOSEDIVE. ANTICIPATE SNOW SHOWERS TO ACCOMPANY THE FRONTAL
PASSAGE AND AS WIND FLOW ALIGNS TO THE NORTHWEST IN ITS WAKE...
LIKELY TO SEE SOME IMPACTS FROM LAKE ENHANCEMENT SNOW SHOWERS
THROUGH MONDAY NIGHT.
THE MUCH GREATER IMPACT WITH THE FRONTAL PASSAGE WILL BE TO
TEMPERATURES AS 850MB TEMPS ON BOTH THE ECMWF AND OP GFS FALL INTO
THE -23 TO -21C RANGE BY TUESDAY. IF THESE NUMBERS EVEN COME CLOSE
TO VERIFYING...HIGH TEMPS ON TUESDAY ARE LIKELY TO STRUGGLE INTO
THE 10-15 DEGREE RANGE AND PROVIDE CENTRAL INDIANA WITH THE
COLDEST AIR OF THE SEASON TO DATE. KNOWING HOW MODELS THIS FAR OUT
TEND TO UNDEROD THE DEPTH OF ARCTIC COLD AND WITH GROWING
CONFIDENCE IN THE INTENSITY OF THE COLD AIRMASS...HAVE CHOSEN TO
UNDERCUT ALLBLEND TEMPS BY 3 TO 4 DEGREES FOR BOTH MONDAY AND
TUESDAY. LOWS MAY BE DOWN NEAR ZERO BY TUESDAY NIGHT.
&&
.AVIATION /DISCUSSION FOR 160000Z TAF ISSUANCE/...
ISSUED AT 935 PM EST TUE JAN 15 2013
0230Z UPDATE...NO CHANGES NEEDED AT THIS TIME. PREVIOUS DISC
FOLLOWS...
NO SIGNIFICANT CHANGES. VFR CONDITIONS ANTICIPATED THROUGHOUT THE
FORECAST PERIOD.
CLOUD COVERAGE WILL CONTINUE TO INCREASE ACROSS CENTRAL INDIANA
AS LOW PRESSURE MOVES OUT OF THE GULF COAST REGION MOVES ACROSS THE
SOUTHERN TENNESSEE VALLEY THIS EVENING. MOISTURE PROFILES HAVE
ALREADY BEGUN TO DEEPEN THIS EVENING WITH CEILINGS AROUND 6-8KFT.
AS THE LOW PRESSURE SHIFTS INTO THE SOUTHERN APPALACHIANS LATE
TONIGHT...MOISTURE ALOFT WILL ALSO BEGIN TO DEPART OFF TO THE EAST
AND CEILINGS ARE EXPECTED TO LIFT AND SCATTER IN THE HOURS
APPROACHING DAYBREAK. HIGH PRESSURE RIDGE THEN BUILDS INTO THE
REGION WEDNESDAY WITH BROAD SUBSIDENCE. WILL SEE SKIES BECOME
MOSTLY CLEAR. LIGHT AND VARIABLE WINDS LATE TONIGHT WILL SHIFT TO
W/SW AND INCREASE TO NEAR 10KTS WEDNESDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP/JAS
SHORT TERM...CP
LONG TERM....RYAN
AVIATION...SMF
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
929 PM EST TUE JAN 15 2013
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 212 PM EST TUE JAN 15 2013
QUIET WEATHER CAN BE EXPECTED UNDER HIGH PRESSURE THROUGH THE END
OF THE WEEK WITH TEMPERATURES NEAR NORMAL FOR THIS TIME OF YEAR.
COULD SEE A BRIEF WARM UP SATURDAY INTO THE 40S BEFORE
TEMPERATURES DROP BACK TO NORMAL SUNDAY AND THEN GET VERY COLD TO
START OUT THE WEEK. A CLIPPER SYSTEM WILL MOVE THROUGH SUNDAY
NIGHT THROUGH MONDAY NIGHT BRINGING CHANCES FOR SNOW.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 929 PM EST TUE JAN 15 2013
LATEST SHORT TERM MODEL GUIDANCE ALONG WITH REGIONAL RADAR LOOPS
SUGGEST PRECIPITATION SHIELD ASSOCIATED WITH SYSTEM MOVING THROUGH
THE TENNESSEE VALLEY SHOULD STAY SOUTH OF THE FORECAST AREA TONIGHT
FOR THE MOST PART. ONLY HAVE SLIGHT CHANCE POPS GOING OVER THE FAR
SOUTHEAST FOR THE REST OF THE NIGHT...SO WILL LEAVE THE POP FORECAST
AS IS.
THIS EVENING/S UPPER AIR INDICATE TEMPERATURES NEAR OR BELOW
FREEZING THROUGHOUT THE COLUMN THIS FAR NORTH...SO THINK THE CHANCES
OF FREEZING RAIN THIS FAR NORTH ARE DIMINISHING.
FINALLY...WITH ONLY WEAK COLD ADVECTION TONIGHT AND SKIES REMAINING
CLOUDY MOST OF THE NIGHT...DECIDED TO BUMP UP THE LOWS A COUPLE OF
DEGREES.
PREVIOUS DISCUSSION FOLLOWS.
SKIES SHOULD START OUT MOSTLY CLOUDY WITH A LOW PRESSURE SYSTEM
MOVING NORTHEAST OUT OF THE GULF AND THROUGH THE SOUTHEASTERN U.S. A
BIT OF MODEL DISAGREEMENT OVER HOW FAR NORTH PRECIPITATION
ASSOCIATED WITH THIS SYSTEM WILL GET DESPITE SIMILAR POSITIONS AND
STRENGTH FOR THE LOW PRESSURE CENTER. THE RAP AND GEM WERE THE
FURTHEST NORTH AND BRING THE PRECIP INTO THE FAR SOUTHEASTERN
COUNTIES. THE GFS KEEPS THE PRECIP WELL TO THE SOUTH...WHILE THE NAM
AND 0Z ECMWF JUST CLIP THE FAR SOUTHEAST WITH A HUNDREDTH OF QPF.
WITH THE VARIETY OF SOLUTIONS SHOULD CARRY A LOW CHANCE POP IN THE
FAR SOUTHEAST WITH DRY WEATHER BUT MOSTLY CLOUDY SKIES ELSEWHERE.
WENT WITH LOWS A DEGREE OR TWO BELOW GUIDANCE WITH EXPECTED COLD
ADVECTION.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
ISSUED AT 212 PM EST TUE JAN 15 2013
HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH THE SHORT TERM. A
LOW PRESSURE SYSTEM MOVING ACROSS THE HUDSON BAY WILL DRAG A COLD
FRONT ACROSS THE GREAT LAKES WEDNESDAY AND WEDNESDAY NIGHT...BUT IT LOOKS
LIKE ALL THE FORCING ASSOCIATED WITH IT WILL STAY WELL NORTH OF THE
AREA. ANOTHER SOUTHERN LOW PRESSURE SYSTEM WHICH WILL MOVE ACROSS
THE SOUTHEAST U.S. DURING THE SAME TIME APPEARS TO BE TOO FAR SOUTH
TO IMPACT POPS HERE. GUIDANCE IS IN GOOD AGREEMENT AND WILL USE AN
AVERAGE WHICH RESULTS IN NEAR NORMAL TEMPERATURES AND DRY WEATHER.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ISSUED AT 248 PM EST TUE JAN 15 2013
FOCUS OF THE EXTENDED PERIOD REMAINS ON THE ARRIVAL OF WHAT
INCREASINGLY APPEARS TO BE THE COLDEST AIRMASS OF THE SEASON AS A
PIEICE OF THE POLAR VORTEX BREAKS OFF AND AMPLIFIES THE UPPER
TROUGH OVER THE EASTERN PART OF THE COUNTRY.
WARMEST DAY OF THE PERIOD WILL BE SATURDAY AS SOUTHERLY FLOW AHEAD
OF A COLD FRONT ENABLES TEMPS TO RISE INTO THE 40S ACROSS THE
FORECAST AREA. LOW PRESSURE WILL TRACK THROUGH THE GREAT LAKES
SATURDAY NIGHT AND BRING THE COLD FRONT THROUGH CENTRAL INDIANA BY
EARLY SUNDAY. THE FRONT WILL USHER IN THE INITIAL SHOT OF COLDER
AIR...AS TEMPS ARE LIKELY TO FALL BACK INTO THE 20S AND LOWER 30S.
PASSAGE OF THE FRONT LOOKS TO BE DRY AS DEEPER MOISTURE IS FOCUSED
CLOSER TO THE LOW ACROSS THE GREAT LAKES. ARCTIC FRONT SET TO DIVE
INTO THE REGION ON MONDAY...USHERING IN MUCH COLDER AIR AS 850MB
TEMPS NOSEDIVE. ANTICIPATE SNOW SHOWERS TO ACCOMPANY THE FRONTAL
PASSAGE AND AS WIND FLOW ALIGNS TO THE NORTHWEST IN ITS WAKE...
LIKELY TO SEE SOME IMPACTS FROM LAKE ENHANCEMENT SNOW SHOWERS
THROUGH MONDAY NIGHT.
THE MUCH GREATER IMPACT WITH THE FRONTAL PASSAGE WILL BE TO
TEMPERATURES AS 850MB TEMPS ON BOTH THE ECMWF AND OP GFS FALL INTO
THE -23 TO -21C RANGE BY TUESDAY. IF THESE NUMBERS EVEN COME CLOSE
TO VERIFYING...HIGH TEMPS ON TUESDAY ARE LIKELY TO STRUGGLE INTO
THE 10-15 DEGREE RANGE AND PROVIDE CENTRAL INDIANA WITH THE
COLDEST AIR OF THE SEASON TO DATE. KNOWING HOW MODELS THIS FAR OUT
TEND TO UNDEROD THE DEPTH OF ARCTIC COLD AND WITH GROWING
CONFIDENCE IN THE INTENSITY OF THE COLD AIRMASS...HAVE CHOSEN TO
UNDERCUT ALLBLEND TEMPS BY 3 TO 4 DEGREES FOR BOTH MONDAY AND
TUESDAY. LOWS MAY BE DOWN NEAR ZERO BY TUESDAY NIGHT.
&&
.AVIATION /DISCUSSION FOR 160000Z TAF ISSUANCE/...
ISSUED AT 508 PM EST TUE JAN 15 2013
NO SIGNIFICANT CHANGES. VFR CONDITIONS ANTICIPATED THROUGHOUT THE
FORECAST PERIOD.
CLOUD COVERAGE WILL CONTINUE TO INCREASE ACROSS CENTRAL INDIANA
AS LOW PRESSURE MOVES OUT OF THE GULF COAST REGION MOVES ACROSS THE
SOUTHERN TENNESSEE VALLEY THIS EVENING. MOISTURE PROFILES HAVE
ALREADY BEGUN TO DEEPEN THIS EVENING WITH CEILINGS AROUND 6-8KFT.
AS THE LOW PRESSURE SHIFTS INTO THE SOUTHERN APPALACHIANS LATE
TONIGHT...MOISTURE ALOFT WILL ALSO BEGIN TO DEPART OFF TO THE EAST
AND CEILINGS ARE EXPECTED TO LIFT AND SCATTER IN THE HOURS
APPROACHING DAYBREAK. HIGH PRESSURE RIDGE THEN BUILDS INTO THE
REGION WEDNESDAY WITH BROAD SUBSIDENCE. WILL SEE SKIES BECOME
MOSTLY CLEAR. LIGHT AND VARIABLE WINDS LATE TONIGHT WILL SHIFT TO
W/SW AND INCREASE TO NEAR 10KTS WEDNESDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP/JAS
SHORT TERM...CP
LONG TERM....RYAN
AVIATION...SMF
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
322 PM EST MON JAN 14 2013
.UPDATE...
THE SYNOPSIS...NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN UPDATED
BELOW.
&&
.SYNOPSIS...
ISSUED AT 320 PM EST MON JAN 14 2013
QUIET WEATHER IS EXPECTED FOR MUCH OF THE PERIOD WITH
TEMPERATURES RETURNING TO NORMAL FOR THIS TIME OF YEAR UNDER HIGH
PRESSURE. BY THE END OF THE LONG TERM THOUGH A CLIPPER SYSTEM COULD
MOVE THROUGH BRINGING CHANCES FOR SNOW AND COLDER TEMPERATURES WITH
IT.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 320 PM EST MON JAN 14 2013
CURRENTLY RADAR MOSAIC SHOWS SOME WEAK ECHOES TO THE SOUTH AND WEST
THAT ARE MOVING NORTHEAST...BUT NO PRECIPITATION IS BEING REPORTED
AT THE GROUND UNDER ANY OF THESE ECHOES AND WITH VERY DRY AIR ALOFT
IN THE SOUNDINGS DO NOT EXPECT TO SEE ANY OF THIS REACH THE GROUND.
SATELLITE SHOWS MOSTLY CLOUDY SKIES ACROSS THE AREA AND TEMPERATURES
ARE IN THE LOW TO MID 20S WITH LIGHT NORTHERLY WINDS.
HIGH PRESSURE WILL CONTINUE TO BUILD IN FROM THE WEST DURING THE
OVERNIGHT. COMBINATION OF STRATOCU AND MID LEVEL CLOUDS WILL HAVE
THE AREA STARTING OUT MOSTLY CLOUDY BUT THESE CLOUDS SHOULD THIN AND
SCATTER OUT FROM NORTHWEST TO SOUTHEAST BY MORNING. GUIDANCE
TEMPERATURES WERE A BIT WARMER THAN LOWS WERE LAST NIGHT AND WITH
COLDER SURFACE/925MB/850MB TEMPERATURES AND SIMILAR CLOUD COVER SEE
NO REASON FOR THIS TO BE TRUE. THUS ADJUSTED TEMPERATURES DOWN A FEW
DEGREES FROM GUIDANCE TO BE A DEGREE OR TWO LOWER THAN LAST NIGHT.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
ISSUED AT 320 PM EST MON JAN 14 2013
QUIET WEATHER IS EXPECTED OVER THE SHORT TERM AS HIGH PRESSURE
REMAINS THE DOMINANT FEATURE OVER CENTRAL INDIANA. AT THIS TIME IT
LOOKS LIKE THE AREA WILL BE IN BETWEEN A LOW PRESSURE SYSTEM COMING
OUT OF THE GULF AND TO VIRGINIA WHILE A CLIPPER MOVES ACROSS THE
GREAT LAKES FROM TUESDAY THROUGH WEDNESDAY NIGHT. THESE SYSTEMS
COULD INCREASE CLOUDS A BIT IN THE SOUTH AND NORTH RESPECTIVELY BUT
THE SURFACE HIGH OVER THE AREA SHOULD KEEP CENTRAL INDIANA DRY. FOR
TEMPERATURES GENERALLY USED A GUIDANCE CONSENSUS WHICH ALLOWED FOR A
LITTLE WARMING TUESDAY THROUGH WEDNESDAY NIGHT WITH SLIGHTLY COOLER
HIGHS ON THURSDAY AFTER THE PASSAGE OF THE CLIPPER TO THE NORTH.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
ISSUED AT 252 PM EST MON JAN 14 2013
FOCUS OF THE EXTENDED PERIOD REMAINS ON A TRANSITION TO MUCH
COLDER AIR ACROSS THE REGION AS THE POLAR VORTEX DIVES INTO
EASTERN CANADA AND SERVES TO AMPLIFY THE UPPER TROUGH OVER THE
EASTERN PART OF THE COUNTRY.
DRY WEATHER AND LARGELY SEASONABLE TEMPS WILL CONTINUE THROUGH
SATURDAY AS NORTHWEST FLOW ALOFT PERSISTS ACROSS THE OHIO VALLEY.
HIGHS IN THE 30S FRIDAY WILL WARM INTO THE 40S SATURDAY AS BRIEF
WARM ADVECTION DEVELOPS AHEAD OF A STRONG WAVE MOVING INTO THE
GREAT LAKES. MODEL CONSENSUS TRACKS THE SURFACE WAVE TO THE NORTH
OF THE REGION SATURDAY NIGHT...WITH THE MAIN IMPACTS TO CENTRAL
INDIANA BEING AN INCREASE IN WINDS AND A WINDSHIFT AS THE INITIAL
SHOT OF COLDER AIR ADVECTS INTO THE AREA. THIS WILL BE FOLLOWED BY
A CLIPPER-LIKE SYSTEM FOR MONDAY...USHERING IN A REINFORCING AND
COLDER AIRMASS AS A PIECE OF OF THE POLAR VORTEX DIVES INTO THE
GREAT LAKES. WHILE MODELS ARE NOT PICKING UP ON A LOT OF MOISTURE
WITH THE CLIPPER...EXPECT SNOW SHOWERS TO ACCOMPANY THE SYSTEM AND
HAVE INCLUDED CHANCE POPS SUNDAY NIGHT AND MONDAY. 850MB TEMPS
BELOW -20C CONTINUE TO SHOW UP OVER THE FORECAST AREA ON BOTH THE OP
GFS AND ECMWF BY MONDAY/TUESDAY. AT THIS POINT HAVE HIGHS FALLING
INTO THE LOWER/MID 20S BY MONDAY. NOT OUT OF THE QUESTION THAT IF
THESE 850MB TEMPS ARE REALIZED THAT HIGHS COULD CONCEIVABLY BE
EVEN COLDER EARLY NEXT WEEK.
&&
.AVIATION /DISCUSSION FOR THE 14/21Z TAF UPDATE/...
ISSUED AT 316 PM EST MON JAN 14 2013
LOW CLOUDS HAVE SCATTERED AT ALL SITES BUT LAF...AND HAVE UPDATED
TAFS TO REFLECT THIS. PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 1222 PM EST MON JAN 14 2013
MVFR CEILINGS LIKELY TO PERSIST THROUGH THE AFTERNOON...AND
POSSIBLY TO SOME DEGREE TONIGHT.
THE COMBINATION OF COLD ADVECTION...GOOD LAPSE RATES AND VEERING
N/NE FLOW IN THE LOWER LEVELS HAS ENABLED CEILINGS AROUND 1500FT
TO REDEVELOP AND EXPAND BACK INTO CENTRAL INDIANA EARLY THIS
AFTERNOON. WITH MOISTURE INCREASING A BIT THROUGH THE BOUNDARY
LAYER...EXPECT MVFR CEILINGS TO MAINTAIN TO SOME DEGREE FOR THE
REST OF THE AFTERNOON. IN ADDITION TO THE STRATOCU...FAIRLY DENSE
CANOPY OF MID LEVEL CLOUDS WILL MOVE ACROSS THE OHIO VALLEY IN FAT
SOUTHWEST FLOW ALOFT. NORTHERLY WINDS WILL BE LESS THAN 10KTS
THROUGH SUNSET.
CLOUD FORECAST TONIGHT HAS SOME UNCERTAINTY AS RAP SOUNDINGS
INDICATING SHALLOW LAYER OF LOW LEVEL MOISTURE PERSISTING. WHILE
FLOW THROUGH 925MB WEAKENS...IT REMAINS FROM THE NORTHEAST INTO
THE OVERNIGHT. HAVE INTRODUCED SCATTERED CEILINGS AT 1500FT
TONIGHT AND WILL ADJUST AS NECESSARY. MID LEVEL CLOUDS WILL
CONTINUE TO MOVE ACROSS THE REGION IN THE SOUTHWEST FLOW AS WELL.
SHOULD FINALLY SEE MOSTLY CLEAR SKIES BY TUESDAY MORNING AS CENTER
OF HIGH PRESSURE BUILDS ACROSS THE OHIO VALLEY WITH DEEPER
SUBSIDENCE NOTED IN THE MODEL SOUNDINGS. WINDS WILL VEER TO THE
NORTHEAST AND REMAIN AT 10KTS OR LESS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP
SHORT TERM...CP
LONG TERM....RYAN
AVIATION...RYAN/NIELD
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
316 PM EST MON JAN 14 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 308 AM EST MON JAN 14 2013
HIGH PRESSURE WILL BUILD FROM THE PLAINS TO THE LOWER GREAT LAKES
AND OHIO VALLEY ALLOWING FOR A DRY FORECAST THROUGH SUNDAY. BELOW
NORMAL TEMPERATURES TO START THE WEEK WILL BECOME SEASONABLE BY
MIDWEEK.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1106 AM EST MON JAN 14 2013
SATELLITE AT 11 AM SHOWS PARTLY CLOUDY SKIES ACROSS MOST OF
CENTRAL INDIANA WITH A BIT MORE CLOUD COVERAGE IN THE NORTHEAST.
EXPECT PARTLY CLOUDY TO BE THE RULE FOR THE REST OF THE DAY. GOING
FORECAST HIGHS IN THE MID 20S TO LOW 30S LOOK RIGHT ON TRACK.
PREVIOUS DISCUSSION FOLLOWS...
MAIN FOCUS TODAY WILL BE ON CLEARING AS STRATOCU DECK WAS CURRENTLY
DROPPING SOUTHEAST ACROSS THE EASTERN HALF OF CENTRAL INDIANA BEHIND
A DEPARTING COLD FRONT ACROSS THE APPALACHIANS.
MODELS IN GOOD AGREEMENT ON PLAINS HIGH PRESSURE BUILDING IN ACROSS
THE FORECAST AREA. MODEL TIME SECTIONS AND SOUNDINGS ARE ALSO SHOWING
THINNING OF THE LOW LEVEL MOISTURE ASSOCIATED WITH THE STRATOCU
DECK...AND SATELLITE TRENDS SUGGEST THEY WILL DEPART TO THE
SOUTHEAST DESPITE WHAT 00Z MOS WAS SUGGESTING. MEANWHILE...UPPER
WAVE IN FAST SOUTHWEST FLOW ALOFT COULD BRING SOME INCREASED CLOUD
COVER LATE TO THE SOUTHEAST COUNTIES. DRY DAY SHOULD ALLOW AREA
CREEKS AND STREAMS TO DROP BELOW FLOOD STAGE AS THEY EMPTY INTO
THE MAIN RIVERS WITH MINOR TO MODERATE FLOODING ON MOST FORECAST
POINTS.
00Z MOS TEMPERATURES AND ALLBLEND MATCH UP PRETTY WELL AND LOOK
REASONABLE CONSIDERING THE NORTHWEST COLD ADVECTION.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 308 AM EST MON JAN 14 2013
MODELS AGREE HIGH PRESSURE AND LIMITED MOISTURE SHOULD ALLOW FOR
LITTLE CLOUD COVER THROUGH THE SHORT TERM. SHOULD ONLY SEE SOME
INCREASE IN CLOUDS SOUTH LATE TUESDAY AS AN INVERTED TROUGH SLIDES
ACROSS THE SOUTHEASTERN STATES AND SOME INCREASE IN CLOUDS NORTH
LATE WEDNESDAY AS A COLD FRONT DROPS SOUTH TO THE LOWER GREAT LAKES.
LOW LEVEL FLOW IS EXPECTED TO VEER TO THE NORTH TONIGHT...NORTHEAST
ON TUESDAY AND SOUTHWEST BY WEDNESDAY. THIS WILL ALLOW TEMPERATURES
TO WARM TO THE MID 30S NORTH AND LOWER 40S SOUTH PER SIMILAR 00Z MOS
AND ALLBLEND BY WEDNESDAY. THE DRY WEATHER WILL ALLOW MINOR TO
MODERATE RIVER FLOODING TO RUN ITS COURSE WITHOUT ANY HITCHES.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
ISSUED AT 252 PM EST MON JAN 14 2013
FOCUS OF THE EXTENDED PERIOD REMAINS ON A TRANSITION TO MUCH
COLDER AIR ACROSS THE REGION AS THE POLAR VORTEX DIVES INTO
EASTERN CANADA AND SERVES TO AMPLIFY THE UPPER TROUGH OVER THE
EASTERN PART OF THE COUNTRY.
DRY WEATHER AND LARGELY SEASONABLE TEMPS WILL CONTINUE THROUGH
SATURDAY AS NORTHWEST FLOW ALOFT PERSISTS ACROSS THE OHIO VALLEY.
HIGHS IN THE 30S FRIDAY WILL WARM INTO THE 40S SATURDAY AS BRIEF
WARM ADVECTION DEVELOPS AHEAD OF A STRONG WAVE MOVING INTO THE
GREAT LAKES. MODEL CONSENSUS TRACKS THE SURFACE WAVE TO THE NORTH
OF THE REGION SATURDAY NIGHT...WITH THE MAIN IMPACTS TO CENTRAL
INDIANA BEING AN INCREASE IN WINDS AND A WINDSHIFT AS THE INITIAL
SHOT OF COLDER AIR ADVECTS INTO THE AREA. THIS WILL BE FOLLOWED BY
A CLIPPER-LIKE SYSTEM FOR MONDAY...USHERING IN A REINFORCING AND
COLDER AIRMASS AS A PIECE OF OF THE POLAR VORTEX DIVES INTO THE
GREAT LAKES. WHILE MODELS ARE NOT PICKING UP ON A LOT OF MOISTURE
WITH THE CLIPPER...EXPECT SNOW SHOWERS TO ACCOMPANY THE SYSTEM AND
HAVE INCLUDED CHANCE POPS SUNDAY NIGHT AND MONDAY. 850MB TEMPS
BELOW -20C CONTINUE TO SHOW UP OVER THE FORECAST AREA ON BOTH THE OP
GFS AND ECMWF BY MONDAY/TUESDAY. AT THIS POINT HAVE HIGHS FALLING
INTO THE LOWER/MID 20S BY MONDAY. NOT OUT OF THE QUESTION THAT IF
THESE 850MB TEMPS ARE REALIZED THAT HIGHS COULD CONCEIVABLY BE
EVEN COLDER EARLY NEXT WEEK.
&&
.AVIATION /DISCUSSION FOR THE 14/21Z TAF UPDATE/...
ISSUED AT 316 PM EST MON JAN 14 2013
LOW CLOUDS HAVE SCATTERED AT ALL SITES BUT LAF...AND HAVE UPDATED
TAFS TO REFLECT THIS. PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 1222 PM EST MON JAN 14 2013
MVFR CEILINGS LIKELY TO PERSIST THROUGH THE AFTERNOON...AND
POSSIBLY TO SOME DEGREE TONIGHT.
THE COMBINATION OF COLD ADVECTION...GOOD LAPSE RATES AND VEERING
N/NE FLOW IN THE LOWER LEVELS HAS ENABLED CEILINGS AROUND 1500FT
TO REDEVELOP AND EXPAND BACK INTO CENTRAL INDIANA EARLY THIS
AFTERNOON. WITH MOISTURE INCREASING A BIT THROUGH THE BOUNDARY
LAYER...EXPECT MVFR CEILINGS TO MAINTAIN TO SOME DEGREE FOR THE
REST OF THE AFTERNOON. IN ADDITION TO THE STRATOCU...FAIRLY DENSE
CANOPY OF MID LEVEL CLOUDS WILL MOVE ACROSS THE OHIO VALLEY IN FAT
SOUTHWEST FLOW ALOFT. NORTHERLY WINDS WILL BE LESS THAN 10KTS
THROUGH SUNSET.
CLOUD FORECAST TONIGHT HAS SOME UNCERTAINTY AS RAP SOUNDINGS
INDICATING SHALLOW LAYER OF LOW LEVEL MOISTURE PERSISTING. WHILE
FLOW THROUGH 925MB WEAKENS...IT REMAINS FROM THE NORTHEAST INTO
THE OVERNIGHT. HAVE INTRODUCED SCATTERED CEILINGS AT 1500FT
TONIGHT AND WILL ADJUST AS NECESSARY. MID LEVEL CLOUDS WILL
CONTINUE TO MOVE ACROSS THE REGION IN THE SOUTHWEST FLOW AS WELL.
SHOULD FINALLY SEE MOSTLY CLEAR SKIES BY TUESDAY MORNING AS CENTER
OF HIGH PRESSURE BUILDS ACROSS THE OHIO VALLEY WITH DEEPER
SUBSIDENCE NOTED IN THE MODEL SOUNDINGS. WINDS WILL VEER TO THE
NORTHEAST AND REMAIN AT 10KTS OR LESS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...MK/CP
SHORT TERM...MK
LONG TERM....RYAN
AVIATION...RYAN/NIELD
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
252 PM EST MON JAN 14 2013
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 308 AM EST MON JAN 14 2013
HIGH PRESSURE WILL BUILD FROM THE PLAINS TO THE LOWER GREAT LAKES
AND OHIO VALLEY ALLOWING FOR A DRY FORECAST THROUGH SUNDAY. BELOW
NORMAL TEMPERATURES TO START THE WEEK WILL BECOME SEASONABLE BY
MIDWEEK.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1106 AM EST MON JAN 14 2013
SATELLITE AT 11 AM SHOWS PARTLY CLOUDY SKIES ACROSS MOST OF
CENTRAL INDIANA WITH A BIT MORE CLOUD COVERAGE IN THE NORTHEAST.
EXPECT PARTLY CLOUDY TO BE THE RULE FOR THE REST OF THE DAY. GOING
FORECAST HIGHS IN THE MID 20S TO LOW 30S LOOK RIGHT ON TRACK.
PREVIOUS DISCUSSION FOLLOWS...
MAIN FOCUS TODAY WILL BE ON CLEARING AS STRATOCU DECK WAS CURRENTLY
DROPPING SOUTHEAST ACROSS THE EASTERN HALF OF CENTRAL INDIANA BEHIND
A DEPARTING COLD FRONT ACROSS THE APPALACHIANS.
MODELS IN GOOD AGREEMENT ON PLAINS HIGH PRESSURE BUILDING IN ACROSS
THE FORECAST AREA. MODEL TIME SECTIONS AND SOUNDINGS ARE ALSO SHOWING
THINNING OF THE LOW LEVEL MOISTURE ASSOCIATED WITH THE STRATOCU
DECK...AND SATELLITE TRENDS SUGGEST THEY WILL DEPART TO THE
SOUTHEAST DESPITE WHAT 00Z MOS WAS SUGGESTING. MEANWHILE...UPPER
WAVE IN FAST SOUTHWEST FLOW ALOFT COULD BRING SOME INCREASED CLOUD
COVER LATE TO THE SOUTHEAST COUNTIES. DRY DAY SHOULD ALLOW AREA
CREEKS AND STREAMS TO DROP BELOW FLOOD STAGE AS THEY EMPTY INTO
THE MAIN RIVERS WITH MINOR TO MODERATE FLOODING ON MOST FORECAST
POINTS.
00Z MOS TEMPERATURES AND ALLBLEND MATCH UP PRETTY WELL AND LOOK
REASONABLE CONSIDERING THE NORTHWEST COLD ADVECTION.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 308 AM EST MON JAN 14 2013
MODELS AGREE HIGH PRESSURE AND LIMITED MOISTURE SHOULD ALLOW FOR
LITTLE CLOUD COVER THROUGH THE SHORT TERM. SHOULD ONLY SEE SOME
INCREASE IN CLOUDS SOUTH LATE TUESDAY AS AN INVERTED TROUGH SLIDES
ACROSS THE SOUTHEASTERN STATES AND SOME INCREASE IN CLOUDS NORTH
LATE WEDNESDAY AS A COLD FRONT DROPS SOUTH TO THE LOWER GREAT LAKES.
LOW LEVEL FLOW IS EXPECTED TO VEER TO THE NORTH TONIGHT...NORTHEAST
ON TUESDAY AND SOUTHWEST BY WEDNESDAY. THIS WILL ALLOW TEMPERATURES
TO WARM TO THE MID 30S NORTH AND LOWER 40S SOUTH PER SIMILAR 00Z MOS
AND ALLBLEND BY WEDNESDAY. THE DRY WEATHER WILL ALLOW MINOR TO
MODERATE RIVER FLOODING TO RUN ITS COURSE WITHOUT ANY HITCHES.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
ISSUED AT 252 PM EST MON JAN 14 2013
FOCUS OF THE EXTENDED PERIOD REMAINS ON A TRANSITION TO MUCH
COLDER AIR ACROSS THE REGION AS THE POLAR VORTEX DIVES INTO
EASTERN CANADA AND SERVES TO AMPLIFY THE UPPER TROUGH OVER THE
EASTERN PART OF THE COUNTRY.
DRY WEATHER AND LARGELY SEASONABLE TEMPS WILL CONTINUE THROUGH
SATURDAY AS NORTHWEST FLOW ALOFT PERSISTS ACROSS THE OHIO VALLEY.
HIGHS IN THE 30S FRIDAY WILL WARM INTO THE 40S SATURDAY AS BRIEF
WARM ADVECTION DEVELOPS AHEAD OF A STRONG WAVE MOVING INTO THE
GREAT LAKES. MODEL CONSENSUS TRACKS THE SURFACE WAVE TO THE NORTH
OF THE REGION SATURDAY NIGHT...WITH THE MAIN IMPACTS TO CENTRAL
INDIANA BEING AN INCREASE IN WINDS AND A WINDSHIFT AS THE INITIAL
SHOT OF COLDER AIR ADVECTS INTO THE AREA. THIS WILL BE FOLLOWED BY
A CLIPPER-LIKE SYSTEM FOR MONDAY...USHERING IN A REINFORCING AND
COLDER AIRMASS AS A PIECE OF OF THE POLAR VORTEX DIVES INTO THE
GREAT LAKES. WHILE MODELS ARE NOT PICKING UP ON A LOT OF MOISTURE
WITH THE CLIPPER...EXPECT SNOW SHOWERS TO ACCOMPANY THE SYSTEM AND
HAVE INCLUDED CHANCE POPS SUNDAY NIGHT AND MONDAY. 850MB TEMPS
BELOW -20C CONTINUE TO SHOW UP OVER THE FORECAST AREA ON BOTH THE OP
GFS AND ECMWF BY MONDAY/TUESDAY. AT THIS POINT HAVE HIGHS FALLING
INTO THE LOWER/MID 20S BY MONDAY. NOT OUT OF THE QUESTION THAT IF
THESE 850MB TEMPS ARE REALIZED THAT HIGHS COULD CONCEIVABLY BE
EVEN COLDER EARLY NEXT WEEK.
&&
.AVIATION /DISCUSSION FOR 141800Z TAF ISSUANCE/...
ISSUED AT 1222 PM EST MON JAN 14 2013
MVFR CEILINGS LIKELY TO PERSIST THROUGH THE AFTERNOON...AND
POSSIBLY TO SOME DEGREE TONIGHT.
THE COMBINATION OF COLD ADVECTION...GOOD LAPSE RATES AND VEERING
N/NE FLOW IN THE LOWER LEVELS HAS ENABLED CEILINGS AROUND 1500FT
TO REDEVELOP AND EXPAND BACK INTO CENTRAL INDIANA EARLY THIS
AFTERNOON. WITH MOISTURE INCREASING A BIT THROUGH THE BOUNDARY
LAYER...EXPECT MVFR CEILINGS TO MAINTAIN TO SOME DEGREE FOR THE
REST OF THE AFTERNOON. IN ADDITION TO THE STRATOCU...FAIRLY DENSE
CANOPY OF MID LEVEL CLOUDS WILL MOVE ACROSS THE OHIO VALLEY IN FAT
SOUTHWEST FLOW ALOFT. NORTHERLY WINDS WILL BE LESS THAN 10KTS
THROUGH SUNSET.
CLOUD FORECAST TONIGHT HAS SOME UNCERTAINTY AS RAP SOUNDINGS
INDICATING SHALLOW LAYER OF LOW LEVEL MOISTURE PERSISTING. WHILE
FLOW THROUGH 925MB WEAKENS...IT REMAINS FROM THE NORTHEAST INTO
THE OVERNIGHT. HAVE INTRODUCED SCATTERED CEILINGS AT 1500FT
TONIGHT AND WILL ADJUST AS NECESSARY. MID LEVEL CLOUDS WILL
CONTINUE TO MOVE ACROSS THE REGION IN THE SOUTHWEST FLOW AS WELL.
SHOULD FINALLY SEE MOSTLY CLEAR SKIES BY TUESDAY MORNING AS CENTER
OF HIGH PRESSURE BUILDS ACROSS THE OHIO VALLEY WITH DEEPER
SUBSIDENCE NOTED IN THE MODEL SOUNDINGS. WINDS WILL VEER TO THE
NORTHEAST AND REMAIN AT 10KTS OR LESS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...MK/CP
SHORT TERM...MK
LONG TERM....RYAN
AVIATION...RYAN
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1235 PM EST MON JAN 14 2013
.UPDATE...
UPDATE SENT EARLIER TO EXPAND IN TIME AND SPACE CLOUD COVER AND
REINTRODUCE FLURRIES FOR MUCH OF THE AREA INTO EARLY AFTERNOON.
LAKE EFFECT CLOUDS WERE HOLDING STRONG ACROSS MUCH OF THE FORECAST
AREA WITH SEVERAL LOCATIONS REPORTING FLURRY ACTIVITY. NO ACCUMS
ARE EXPECTED SO KEPT THINGS SIMPLE AND WENT WITH SCT FLURRIES INTO
EARLY AFTERNOON WHEN LL FLOW WILL WEAKEN AND DRY AIR BECOME MORE
ENTRAINED. NO MODIFICATIONS TO ANY OTHER PARTS OF THE FORECAST WITH
TEMPS STILL GENERALLY ON TRACK.
&&
.AVIATION...
MVFR CIGS HOLDING AS A RESULT OF LAKE EFFECT CLOUD COVER.
CONDITIONS SHOULD IMPROVE BY LATE AFTERNOON AS DRIER AIR WORKS IN.
TAFS PATCHED UP TO REFLECT THIS WITH VFR CONDITIONS ANTICIPATED
AFTER 00Z AND FOR THE REMAINDER OF THE PERIOD.
&&
.PREV DISCUSSION... /ISSUED 645 AM EST MON JAN 14 2013/
SHORT TERM... /TODAY THROUGH TUESDAY NIGHT/
NMRS MESOGAMMA THERMAL ROLLS CRNTLY BLOSSOMING WSR-88 VCP 31
RETURNS ERLY THIS MORNING...EXTNDG FARTHER SOUTH THAN TYPICAL LAKE
RESPONSE...AT LEAST TO KRCR-WABASH LN. LK MSTR ENHANCEMENT RATHER
MINIMAL GIVEN ONLY LWR TEENS LK/8H THERMAL DIFFERENTIAL ACRS FAR
SRN LK MI. THIN LYR LIFT ON NOSE OF 30-35KT 8H JETLET/SHORTWAVE FM
NRN IL AT 03 UTC. 8H PSUEDOFRONT APPEARS ORTHOGONALLY ALONG
LEADING EDGE OF RAP ANALYZED THIN LYR NEAR SFC/950-900 MB/ FGEN
ZONE LAID OUT SRN LK HUR-SERN FA-SRN IN...WHICH SHOULD QUELL
FLURRIES MENTION BY ABOUT 14 UTC. THIS THE ONLY SENSIBLE WX IN THE
SHORT TERM PD. THEREAFTER...THE DEEP SCOUR OF MSTR BY CP CANADIAN
PLAINS AIRMASS TO CONT TO ERODE RMNG STRATOCU FIELD TDY ON LEADING
EDGE OF 1034MB RIDGE. ANTICIPATE POOR THERMAL RECOVERY THOUGH IN
LIGHT OF SIG AIRMASS EXCHANGE ALONG WITH POTNL INCRS IN CI/CS LTR
THIS AFTN ASSOCD WITH INTENSE ULVL JETSTREAK ON ORDER OF 180-200
KTS LIFTG THROUGH MID MS VLY TO FAR SRN ONT THIS EVE. GOOD POTNL
FOR DECOUPLED BLYR LATE TONIGHT. DOWN TO LWR TEENS/PSBLY LWR
SINGLE DIGITS...SPCLY FAR WRN CWA WITH BEST DURATION FOR LONGWAVE
LOSSES. SLIGHT SFC- 925MB THERMAL MODIFICATION BY DAYBREAK
WED...ALONG WITH INCRSD MIXED BL...WITH CWA ON SERN PERIPHERY OF
RAMPING FLOW ASSOCD WITH HIGH BELTED CLIPPER.
LONG TERM... /WEDNESDAY THROUGH SUNDAY/
A LONGWAVE TROF WILL AMPLIFY OVER EASTERN NORTH AMERICA THIS
PERIOD AS A PRECURSOR OF THE ARRIVAL OF VERY COLD AIR LATE IN THE
PERIOD. THE 500 MB GFS AND CANADIAN ANALOGS...GFS AND CANADIAN
ENSEMBLES AND THE ECMWF ALL SUPPORT THE ESTABLISHMENT OF A MUCH
COLDER PATTERN EARLY NEXT WEEK. AHEAD OF THE AMPLIFYING UPPER
TROF...A WEAKER TROF WILL MOVE ACROSS THE AREA ACCOMPANIED BY A
COLD FRONT WEDNESDAY NIGHT. THERE IS NOT MUCH SUPPORT FOR
PRECIPITATION WITH THIS SYSTEM INCLUDING LAKE EFFECT SNOW.
MOISTURE IS LIMITED AND FORCING IS WEAK. THE MOST UNSTABLE LAKE
EFFECT DELTA T VALUES BEFORE SUNDAY ARE 10 TO 14...BUT WITH AN
UNFAVORABLE FETCH OVER MUCH OF THE PERIOD...KEPT THE FORECAST DRY.
FOR LATE IN THE PERIOD...GUT FEELING HIGHS SUNDAY ARE TOO WARM.
HOWEVER...LEFT HIGHS AROUND 30 MOST AREAS GIVEN THE UNCERTAINTY OF
THE ARRIVAL TIME OF THE FRONT. THE GFS MEAN ENSEMBLE MOS HIGHS
SUNDAY ARE 22 TO 27 WHICH MAY BE ON TRACK. A PERIOD OF LIGHT SNOW
IN THE ARCTIC AIR MAY ALSO EVENTUALLY NEED TO BE ADDED TO THE
FORECAST SUNDAY IF A FASTER FRONTAL PASSAGE PREVAILS. TEMPERATURES
MAY BE STEADY OR SLOWING FALLING SUNDAY. FOR NOW...WENT WITH A
SMALL DIURNAL RISE SUNDAY.
MARINE...
LOOK FOR RAPIDLY INCRSG GRADIENT FLOW AS ULVL TROF SHIFTS GRDLY
EWD INTO WRN GRTLKS BY LATE TUE. MIDWEEK MARINE HEADLINES TO LATER
FOCUS ON NEED FOR NEARSHORE GALE WATCH/WARNING WITH BEST WINDOW IN
THE 12-21 UTC WED TIMEFRAME. ACCELERATION RATE OF FLOW SHOULD
PRECLUDE LEAD IN SC.Y...THOUGH LATER FCSTS TO FINE TUNE AS NEED
BE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SHORT TERM...MURPHY
LONG TERM...SKIPPER
AVIATION...FISHER
UPDATE...FISHER
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1222 PM EST MON JAN 14 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 308 AM EST MON JAN 14 2013
HIGH PRESSURE WILL BUILD FROM THE PLAINS TO THE LOWER GREAT LAKES
AND OHIO VALLEY ALLOWING FOR A DRY FORECAST THROUGH SUNDAY. BELOW
NORMAL TEMPERATURES TO START THE WEEK WILL BECOME SEASONABLE BY
MIDWEEK.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1106 AM EST MON JAN 14 2013
SATELLITE AT 11 AM SHOWS PARTLY CLOUDY SKIES ACROSS MOST OF
CENTRAL INDIANA WITH A BIT MORE CLOUD COVERAGE IN THE NORTHEAST.
EXPECT PARTLY CLOUDY TO BE THE RULE FOR THE REST OF THE DAY. GOING
FORECAST HIGHS IN THE MID 20S TO LOW 30S LOOK RIGHT ON TRACK.
PREVIOUS DISCUSSION FOLLOWS...
MAIN FOCUS TODAY WILL BE ON CLEARING AS STRATOCU DECK WAS CURRENTLY
DROPPING SOUTHEAST ACROSS THE EASTERN HALF OF CENTRAL INDIANA BEHIND
A DEPARTING COLD FRONT ACROSS THE APPALACHIANS.
MODELS IN GOOD AGREEMENT ON PLAINS HIGH PRESSURE BUILDING IN ACROSS
THE FORECAST AREA. MODEL TIME SECTIONS AND SOUNDINGS ARE ALSO SHOWING
THINNING OF THE LOW LEVEL MOISTURE ASSOCIATED WITH THE STRATOCU
DECK...AND SATELLITE TRENDS SUGGEST THEY WILL DEPART TO THE
SOUTHEAST DESPITE WHAT 00Z MOS WAS SUGGESTING. MEANWHILE...UPPER
WAVE IN FAST SOUTHWEST FLOW ALOFT COULD BRING SOME INCREASED CLOUD
COVER LATE TO THE SOUTHEAST COUNTIES. DRY DAY SHOULD ALLOW AREA
CREEKS AND STREAMS TO DROP BELOW FLOOD STAGE AS THEY EMPTY INTO
THE MAIN RIVERS WITH MINOR TO MODERATE FLOODING ON MOST FORECAST
POINTS.
00Z MOS TEMPERATURES AND ALLBLEND MATCH UP PRETTY WELL AND LOOK
REASONABLE CONSIDERING THE NORTHWEST COLD ADVECTION.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 308 AM EST MON JAN 14 2013
MODELS AGREE HIGH PRESSURE AND LIMITED MOISTURE SHOULD ALLOW FOR
LITTLE CLOUD COVER THROUGH THE SHORT TERM. SHOULD ONLY SEE SOME
INCREASE IN CLOUDS SOUTH LATE TUESDAY AS AN INVERTED TROUGH SLIDES
ACROSS THE SOUTHEASTERN STATES AND SOME INCREASE IN CLOUDS NORTH
LATE WEDNESDAY AS A COLD FRONT DROPS SOUTH TO THE LOWER GREAT LAKES.
LOW LEVEL FLOW IS EXPECTED TO VEER TO THE NORTH TONIGHT...NORTHEAST
ON TUESDAY AND SOUTHWEST BY WEDNESDAY. THIS WILL ALLOW TEMPERATURES
TO WARM TO THE MID 30S NORTH AND LOWER 40S SOUTH PER SIMILAR 00Z MOS
AND ALLBLEND BY WEDNESDAY. THE DRY WEATHER WILL ALLOW MINOR TO
MODERATE RIVER FLOODING TO RUN ITS COURSE WITHOUT ANY HITCHES.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
ISSUED AT 331 AM EST MON JAN 14 2013
A COOL DRY WEATHER PATTERN WILL REMAIN IN PLACE FOR MOST OF THE
LONG TERM PERIOD. A DISTURBANCE WILL PASS ACROSS THE GREAT LAKES
REGION ON SATURDAY...BUT WILL NOT IMPACT CENTRAL INDIANA. THE MAIN
FOCUS OF THE EXTENDED PERIOD IS AT THE TAIL END WHEN A BROAD
UPPER LEVEL TROUGH WILL BRING THE NEXT CHANCE FOR SOME SNOW TO
CENTRAL INDIANA. THE EURO IS THE MOST AGGRESSIVE WITH THE
LOW...HINTING AT SOME ACCUMULATING SNOWFALL...AND THE LATEST
INITIALIZATION IS FAVORING THE EURO OVER THE GFS. WILL NOT DEVIATE
THIS FAR OUT. BEYOND THAT...MODELS ARE HINTING AT A VERY FRIGID
AIRMASS BY THE MIDDLE OF NEXT WEEK.
&&
.AVIATION /DISCUSSION FOR 141800Z TAF ISSUANCE/...
ISSUED AT 1222 PM EST MON JAN 14 2013
MVFR CEILINGS LIKELY TO PERSIST THROUGH THE AFTERNOON...AND
POSSIBLY TO SOME DEGREE TONIGHT.
THE COMBINATION OF COLD ADVECTION...GOOD LAPSE RATES AND VEERING
N/NE FLOW IN THE LOWER LEVELS HAS ENABLED CEILINGS AROUND 1500FT
TO REDEVELOP AND EXPAND BACK INTO CENTRAL INDIANA EARLY THIS
AFTERNOON. WITH MOISTURE INCREASING A BIT THROUGH THE BOUNDARY
LAYER...EXPECT MVFR CEILINGS TO MAINTAIN TO SOME DEGREE FOR THE
REST OF THE AFTERNOON. IN ADDITION TO THE STRATOCU...FAIRLY DENSE
CANOPY OF MID LEVEL CLOUDS WILL MOVE ACROSS THE OHIO VALLEY IN FAT
SOUTHWEST FLOW ALOFT. NORTHERLY WINDS WILL BE LESS THAN 10KTS
THROUGH SUNSET.
CLOUD FORECAST TONIGHT HAS SOME UNCERTAINTY AS RAP SOUNDINGS
INDICATING SHALLOW LAYER OF LOW LEVEL MOISTURE PERSISTING. WHILE
FLOW THROUGH 925MB WEAKENS...IT REMAINS FROM THE NORTHEAST INTO
THE OVERNIGHT. HAVE INTRODUCED SCATTERED CEILINGS AT 1500FT
TONIGHT AND WILL ADJUST AS NECESSARY. MID LEVEL CLOUDS WILL
CONTINUE TO MOVE ACROSS THE REGION IN THE SOUTHWEST FLOW AS WELL.
SHOULD FINALLY SEE MOSTLY CLEAR SKIES BY TUESDAY MORNING AS CENTER
OF HIGH PRESSURE BUILDS ACROSS THE OHIO VALLEY WITH DEEPER
SUBSIDENCE NOTED IN THE MODEL SOUNDINGS. WINDS WILL VEER TO THE
NORTHEAST AND REMAIN AT 10KTS OR LESS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...MK/CP
SHORT TERM...MK
LONG TERM....TDUD
AVIATION...RYAN
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
645 AM EST MON JAN 14 2013
.AVIATION... /12 UTC TAFS/
ONLY MINOR CHNGS WRT LATEST TAFS. LEADING EDGE CLEARING SLOWING
INVOF KSBN PER LAKE INFLUENCE...THOUGH CIGS SHOULD BE VFR/UNLIMITED
BY ABOUT 14-1430 UTC AT KSBN AIRFIELD. END OF FUEL ALT CONDS MORE
IMMINENT AT KFWA...WITH VFR CONDS ASSURED THROUGH THE END OF THE
FCST PD.
&&
.SHORT TERM... /TODAY THROUGH TUESDAY NIGHT/
NMRS MESOGAMMA THERMAL ROLLS CRNTLY BLOSSOMING WSR-88 VCP 31
RETURNS ERLY THIS MORNING...EXTNDG FARTHER SOUTH THAN TYPICAL LAKE
RESPONSE...AT LEAST TO KRCR-WABASH LN. LK MSTR ENHANCEMENT RATHER
MINIMAL GIVEN ONLY LWR TEENS LK/8H THERMAL DIFFERENTIAL ACRS FAR
SRN LK MI. THIN LYR LIFT ON NOSE OF 30-35KT 8H JETLET/SHORTWAVE FM
NRN IL AT 03 UTC. 8H PSUEDOFRONT APPEARS ORTHOGONALLY ALONG
LEADING EDGE OF RAP ANALYZED THIN LYR NEAR SFC/950-900 MB/ FGEN
ZONE LAID OUT SRN LK HUR-SERN FA-SRN IN...WHICH SHOULD QUELL
FLURRIES MENTION BY ABOUT 14 UTC. THIS THE ONLY SENSIBLE WX IN THE
SHORT TERM PD. THEREAFTER...THE DEEP SCOUR OF MSTR BY CP CANADIAN
PLAINS AIRMASS TO CONT TO ERODE RMNG STRATOCU FIELD TDY ON LEADING
EDGE OF 1034MB RIDGE. ANTICIPATE POOR THERMAL RECOVERY THOUGH IN
LIGHT OF SIG AIRMASS EXCHANGE ALONG WITH POTNL INCRS IN CI/CS LTR
THIS AFTN ASSOCD WITH INTENSE ULVL JETSTREAK ON ORDER OF 180-200
KTS LIFTG THROUGH MID MS VLY TO FAR SRN ONT THIS EVE. GOOD POTNL
FOR DECOUPLED BLYR LATE TONIGHT. DOWN TO LWR TEENS/PSBLY LWR
SINGLE DIGITS...SPCLY FAR WRN CWA WITH BEST DURATION FOR LONGWAVE
LOSSES. SLIGHT SFC- 925MB THERMAL MODIFICATION BY DAYBREAK
WED...ALONG WITH INCRSD MIXED BL...WITH CWA ON SERN PERIPHERY OF
RAMPING FLOW ASSOCD WITH HIGH BELTED CLIPPER.
&&
.LONG TERM... /WEDNESDAY THROUGH SUNDAY/
A LONGWAVE TROF WILL AMPLIFY OVER EASTERN NORTH AMERICA THIS
PERIOD AS A PRECURSOR OF THE ARRIVAL OF VERY COLD AIR LATE IN THE
PERIOD. THE 500 MB GFS AND CANADIAN ANALOGS...GFS AND CANADIAN
ENSEMBLES AND THE ECMWF ALL SUPPORT THE ESTABLISHMENT OF A MUCH
COLDER PATTERN EARLY NEXT WEEK. AHEAD OF THE AMPLIFYING UPPER
TROF...A WEAKER TROF WILL MOVE ACROSS THE AREA ACCOMPANIED BY A
COLD FRONT WEDNESDAY NIGHT. THERE IS NOT MUCH SUPPORT FOR
PRECIPITATION WITH THIS SYSTEM INCLUDING LAKE EFFECT SNOW.
MOISTURE IS LIMITED AND FORCING IS WEAK. THE MOST UNSTABLE LAKE
EFFECT DELTA T VALUES BEFORE SUNDAY ARE 10 TO 14...BUT WITH AN
UNFAVORABLE FETCH OVER MUCH OF THE PERIOD...KEPT THE FORECAST DRY.
FOR LATE IN THE PERIOD...GUT FEELING HIGHS SUNDAY ARE TOO WARM.
HOWEVER...LEFT HIGHS AROUND 30 MOST AREAS GIVEN THE UNCERTAINTY OF
THE ARRIVAL TIME OF THE FRONT. THE GFS MEAN ENSEMBLE MOS HIGHS
SUNDAY ARE 22 TO 27 WHICH MAY BE ON TRACK. A PERIOD OF LIGHT SNOW
IN THE ARCTIC AIR MAY ALSO EVENTUALLY NEED TO BE ADDED TO THE
FORECAST SUNDAY IF A FASTER FRONTAL PASSAGE PREVAILS. TEMPERATURES
MAY BE STEADY OR SLOWING FALLING SUNDAY. FOR NOW...WENT WITH A
SMALL DIURNAL RISE SUNDAY.
&&
.MARINE...
LOOK FOR RAPIDLY INCRSG GRADIENT FLOW AS ULVL TROF SHIFTS GRDLY
EWD INTO WRN GRTLKS BY LATE TUE. MIDWEEK MARINE HEADLINES TO LATER
FOCUS ON NEED FOR NEARSHORE GALE WATCH/WARNING WITH BEST WINDOW IN
THE 12-21 UTC WED TIMEFRAME. ACCELERATION RATE OF FLOW SHOULD
PRECLUDE LEAD IN SC.Y...THOUGH LATER FCSTS TO FINE TUNE AS NEED
BE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LMZ043-046.
&&
$$
SHORT TERM...MURPHY
LONG TERM...SKIPPER
AVIATION...MURPHY
MARINE...MURPHY
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
523 AM EST MON JAN 14 2013
.SHORT TERM... /TODAY THROUGH TUESDAY NIGHT/
NMRS MESOGAMMA THERMAL ROLLS CRNTLY BLOSSOMING WSR-88 VCP 31
RETURNS ERLY THIS MORNING...EXTNDG FARTHER SOUTH THAN TYPICAL LAKE
RESPONSE...AT LEAST TO KRCR-WABASH LN. LK MSTR ENHANCEMENT RATHER
MINIMAL GIVEN ONLY LWR TEENS LK/8H THERMAL DIFFERENTIAL ACRS FAR
SRN LK MI. THIN LYR LIFT ON NOSE OF 30-35KT 8H JETLET/SHORTWAVE FM
NRN IL AT 03 UTC. 8H PSUEDOFRONT APPEARS ORTHOGONALLY ALONG
LEADING EDGE OF RAP ANALYZED THIN LYR NEAR SFC/950-900 MB/ FGEN
ZONE LAID OUT SRN LK HUR-SERN FA-SRN IN...WHICH SHOULD QUELL
FLURRIES MENTION BY ABOUT 14 UTC. THIS THE ONLY SENSIBLE WX IN THE
SHORT TERM PD. THEREAFTER...THE DEEP SCOUR OF MSTR BY CP CANADIAN
PLAINS AIRMASS TO CONT TO ERODE RMNG STRATOCU FIELD TDY ON LEADING
EDGE OF 1034MB RIDGE. ANTICIPATE POOR THERMAL RECOVERY THOUGH IN
LIGHT OF SIG AIRMASS EXCHANGE ALONG WITH POTNL INCRS IN CI/CS LTR
THIS AFTN ASSOCD WITH INTENSE ULVL JETSTREAK ON ORDER OF 180-200
KTS LIFTG THROUGH MID MS VLY TO FAR SRN ONT THIS EVE. GOOD POTNL
FOR DECOUPLED BLYR LATE TONIGHT. DOWN TO LWR TEENS/PSBLY LWR
SINGLE DIGITS...SPCLY FAR WRN CWA WITH BEST DURATION FOR LONGWAVE
LOSSES. SLIGHT SFC- 925MB THERMAL MODIFICATION BY DAYBREAK
WED...ALONG WITH INCRSD MIXED BL...WITH CWA ON SERN PERIPHERY OF
RAMPING FLOW ASSOCD WITH HIGH BELTED CLIPPER.
&&
.LONG TERM... /WEDNESDAY THROUGH SUNDAY/
A LONGWAVE TROF WILL AMPLIFY OVER EASTERN NORTH AMERICA THIS
PERIOD AS A PRECURSOR OF THE ARRIVAL OF VERY COLD AIR LATE IN THE
PERIOD. THE 500 MB GFS AND CANADIAN ANALOGS...GFS AND CANADIAN
ENSEMBLES AND THE ECMWF ALL SUPPORT THE ESTABLISHMENT OF A MUCH
COLDER PATTERN EARLY NEXT WEEK. AHEAD OF THE AMPLIFYING UPPER
TROF...A WEAKER TROF WILL MOVE ACROSS THE AREA ACCOMPANIED BY A
COLD FRONT WEDNESDAY NIGHT. THERE IS NOT MUCH SUPPORT FOR
PRECIPITATION WITH THIS SYSTEM INCLUDING LAKE EFFECT SNOW.
MOISTURE IS LIMITED AND FORCING IS WEAK. THE MOST UNSTABLE LAKE
EFFECT DELTA T VALUES BEFORE SUNDAY ARE 10 TO 14...BUT WITH AN
UNFAVORABLE FETCH OVER MUCH OF THE PERIOD...KEPT THE FORECAST DRY.
FOR LATE IN THE PERIOD...GUT FEELING HIGHS SUNDAY ARE TOO WARM.
HOWEVER...LEFT HIGHS AROUND 30 MOST AREAS GIVEN THE UNCERTAINTY OF
THE ARRIVAL TIME OF THE FRONT. THE GFS MEAN ENSEMBLE MOS HIGHS
SUNDAY ARE 22 TO 27 WHICH MAY BE ON TRACK. A PERIOD OF LIGHT SNOW
IN THE ARCTIC AIR MAY ALSO EVENTUALLY NEED TO BE ADDED TO THE
FORECAST SUNDAY IF A FASTER FRONTAL PASSAGE PREVAILS. TEMPERATURES
MAY BE STEADY OR SLOWING FALLING SUNDAY. FOR NOW...WENT WITH A
SMALL DIURNAL RISE SUNDAY.
&&
.AVIATION... /06 UTC TAFS/
INCRSD ENTRAINMENT OF DRIER AIR ACRS NRN IL/SRN WI CIRCUITOUSLY VIA
LAND/AROUND SRN TIP OF LK MI AND INTO NRN IN. THIS SHOULD SUPPORT A
MORE RAPID RECOVERY OUT OF FUEL ALT CONDS AT KSBN/AROUND 10 UTC.
THIS APPROX SAME TIME AS KFWA WHERE LAKE INFLUENCE LACKS IN BACKED
WRLY/CROSS SHORT LAKE AXIS FLOW.
&&
.MARINE...
LOOK FOR RAPIDLY INCRSG GRADIENT FLOW AS ULVL TROF SHIFTS GRDLY
EWD INTO WRN GRTLKS BY LATE TUE. MIDWEEK MARINE HEADLINES TO LATER
FOCUS ON NEED FOR NEARSHORE GALE WATCH/WARNING WITH BEST WINDOW IN
THE 12-21 UTC WED TIMEFRAME. ACCELERATION RATE OF FLOW SHOULD
PRECLUDE LEAD IN SC.Y...THOUGH LATER FCSTS TO FINE TUNE AS NEED
BE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LMZ043-046.
&&
$$
SHORT TERM...MURPHY
LONG TERM...SKIPPER
AVIATION...MURPHY
MARINE...MURPHY
AREA FORECAST DISCUSSION
NWS GOODLAND KS
438 PM MST TUE JAN 15 2013
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 212 PM MST TUE JAN 15 2013
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOWS LONGWAVE TROUGH EXTENDING
FROM THE GREAT LAKES ACROSS CENTRAL KANSAS INTO NORTHERN MEXICO. CWA
IS CURRENTLY ON SUBSIDENT SIDE OF TROUGH AXIS UNDER SHORTWAVE
RIDGING. A WEAK SHORTWAVE TROUGH OVER MONTANA IS CURRENTLY MOVING
THROUGH N/NW FLOW ALONG THE BACK SIDE OF THE TROUGH.
THIS FEATURE IS EXPECTED TO SPLIT WITH A WEAK PIECE OF ENERGY MOVING
SOUTH ACROSS EASTERN COLORADO TONIGHT. WITH MAIN H3 JET AXIS WELL
NORTH OF THE CWA...I AM ONLY ANTICIPATING WEAK FORCING. MODEL
SOUNDINGS INDICATE A SATURATED LEVEL BETWEEN 800-600MB. WITH WEAK
FORCING IN THE WEST...AND VERY LITTLE IN THE WAY OF QPF SHOWN BY
AVAILABLE GUIDANCE I LIMITED SLIGHT CHANCE POPS TO WESTERN CWA THIS
EVENING AND OVERNIGHT...AND SCATTERED FLURRIES ELSEWHERE. EVEN IN
THE WEST WHERE MEASURABLE SNOW IS POSSIBLE I WOULD ONLY ANTICIPATE
A FEW TENTHS OF AN INCH WITH THIS SYSTEM.
SUBSIDENCE ALONG AND A MUCH DRIER AIR MASS WILL SPREAD EAST
WEDNESDAY WITH W/NW FLOW DEVELOPING. AIR MASS HAS ALREADY MODIFIED
WITH SHORTWAVE RIDGING THIS AFTERNOON AND SHOULD CONTINUE TO MODIFY
WED WITH HIGHS IN THE 40S/NEAR 50. THE SNOW PACK IN THE WEST AND NE
WILL STILL KEEP HIGHS SLIGHTLY COOLER...HOWEVER WITH WESTERLY WINDS
WE SHOULD STILL SEE HIGHS AROUND 40F AT THE COLDEST. A CONCERN FOR
WED WILL BE WINDS...WITH BREEZY TO WINDY CONDITIONS ANTICIPATED. I
AM LESS CONFIDENT HOW WINDY IT WILL BE WITH LIMITED MIXING HEIGHTS
BASED ON SOUNDING ANALYSIS. IF WE MIX MUCH HIGHER THAN CURRENT
SOUNDINGS SUGGEST...THEN WE COULD SEE ADVISORY CRITERIA MET...
ESPECIALLY IF WE USE THE NAM WINDS ALOFT. FOR NOW...I LIMITED WINDS
TO JUST UNDER ADVISORY CRITERIA WED AFTERNOON.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 212 PM MST TUE JAN 15 2013
FORECAST PROBLEMS WILL BE THE AMOUNT OF WARMUP BEFORE THE NEXT VERY
COLD AIR MASS ARRIVES AND HOW COLD WILL THAT AIR MASS ALONG WITH
WHEN IT ARRIVES. SATELLITE SHOWING AN AMPLIFIED FLOW STARTING WITH
A BROAD...DEEP AND COMPLICATED UPPER TROUGH OVER THE WESTERN HALF OF
THE PACIFIC WHICH IS MAINTAINING/AMPLIFYING AN UPPER RIDGE NEAR THE
WEST COAST OF NORTH AMERICA. THIS TRANSITIONS TO A TROUGH OVER THE
CENTER OF THE COUNTRY WHICH HAS/CONTINUES TO SPLIT. WARMER AIR MASS
STARTING TO WORK ITS WAY INTO THE REGION.
AT JET LEVEL...THE MODELS INITIALIZED FINE WITH THE ECMWF SLIGHTLY
WORSE THAN THE OTHERS. SATELLITE AND UPPER AIR ANALYSIS SHOW THE
MODELS HAVE INITIALIZED WELL AT MID LEVELS. HOWEVER WOULD HAVE TO
SLIGHTLY FAVOR THE UKMET/CANADIAN OVER THE NAM/ECMWF. AT THE
SURFACE THE SREF WAS DOING A LITTLE BETTER THAN THE ECMWF. THE UKMET
WAS DOING A LITTLE BETTER THAN THE ECMWF AND GFS ON THE LOW LEVEL
THERMAL FIELD.
WEDNESDAY NIGHT/THURSDAY...MAIN STORM TRACK REMAINS WELL NORTH OF
THE AREA AND UNDER SUBSIDENCE FROM THE JET. FLOW ALOFT IS MORE
NORTHWEST WITH LITTLE TO NO CLOUD COVER EXPECTED AT THIS TIME.
WINDS MAY DROP OFF LATE IN THE NIGHT MAINLY IN THE WEST. SURFACE
RIDGE MOVES THROUGH EARLY IN THE DAY ON THURSDAY WITH WINDS SHIFTING
MORE TOWARD THE SOUTH IN THE AFTERNOON. ADJUSTED TEMPERATURES UP A
LITTLE.
THURSDAY NIGHT/FRIDAY...STORM TRACK STILL NORTH OF THE AREA WITH
WEST TO NORTHWEST FLOW ALOFT. THERE MAY BE A LITTLE MORE CLOUD
COVER DURING THE NIGHT AS A WEAK SYSTEM MOVES THROUGH IN THE FLOW
BUT AGAIN LITTLE TO NO CLOUD COVER EXPECTED. DOWNSLOPE COMPONENT IS
MUCH BETTER ON THE WINDS AND ALL MODELS ARE SIMILAR IN THEIR INCREASE
IN THE 850 MB TEMPERATURES. ALSO WOULD EXPECT THE WARM AIR ADVECTION
AND DOWNSLOPE WILL BE BETTER THAN DEPICTED SINCE THIS WILL BE AHEAD
OF THE INITIAL PUSH OF COLDER THAT WILL COME IN ON SATURDAY. SO FELT
COMFORTABLE IN WARMING UP MAXES FROM THE CURRENT PACKAGE. IT IS
POSSIBLE THAT ADDITIONAL RAISING OF THE MAXES WILL BE POSSIBLE.
FRIDAY NIGHT THROUGH TUESDAY...BIG CHANGE IN THE WEATHER...TO MUCH
COLDER TEMPERATURES THIS WEEKEND INTO THE BEGINNING OF NEXT WEEK...
STILL LOOKS ON TRACK. THERE ARE STILL DIFFERENCES IN THE MODELS BUT
THEY ARE MUCH CLOSER THAN YESTERDAY WHICH INCREASES CONFIDENCE ON
THE MAGNITUDE AND ESPECIALLY THE TIMING. SATURDAY LOOKS TO BE VERY
TRICKY. THE INITIAL PUSH IS COMING IN A LITTLE FASTER AND LOOKS
LIKE IT MAY ARRIVE LATE MORNING INTO EARLY AFTERNOON ESPECIALLY IN
THE NORTHEAST HALF OF THE AREA. SO THERE LOOKS TO BE A GOOD GRADIENT
ACROSS MY AREA WHICH WILL NEED TO BE RESOLVED AS WE GET MUCH CLOSER
TO THE DAY. AT THIS TIME TOOK WHAT WAS GIVEN TO ME BY THE CRH_INIT
AND NUDGED DOWN A LITTLE AS I BLENDED WITH NEIGHBORS.
FIRST PUSH OF THE COLD AIR LOOKS TO BE WELL ENTRENCHED BY 12Z
SUNDAY. MODELS WANT TO SCOUR OUT THE COLD AIR DURING THE DAY AS WINDS
SHIFT TO THE WEST BEFORE THE COLDEST AIR ARRIVES SUNDAY NIGHT. NOT
ENTIRELY SOLD ON THAT. SO AFTER COLLABORATION WITH NEIGHBORS DID
LOWER MAXES FROM WHAT WAS GIVEN BY THE INIT. VERY COLD AIR TO
ARRIVE SUNDAY NIGHT INTO MONDAY PER MODEL CONSENSUS. AFTER
COLLABORATION FELT VERY COMFORTABLE IN LOWERING MAXES SIGNIFICANTLY.
WHEN THE COLD AIR COMES IN SUNDAY NIGHT AND MONDAY FLURRIES WILL BE
POSSIBLE. THEN MODELS WANT TO REALLY SCOUR OUT THE COLD AIR ON
TUESDAY AND AGAIN NOT SOLD ON THAT. HOWEVER...THE INIT GAVE ME COOLER
TEMPERATURES THAN WHAT THE MODEL 850 TEMPERATURES SAY. SO AGREED WITH
SURROUNDING OFFICES IN LEAVING THOSE TEMPERATURES ALONE FOR NOW.
THANKS TO ALL FOR THE COLLABORATION.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 433 PM MST TUE JAN 15 2013
MID LEVEL CLOUDS WILL INCREASE THIS EVENING AHEAD OF A SHORTWAVE
THAT WILL MOVE SOUTH IN NORTHERLY FLOW ACROSS THE REGION. BEST
DYNAMICS AND MOISTURE WILL BE WEST OF THE TERMINALS. SOME FLURRIES
WILL BE POSSIBLE AT THE TERMINALS AROUND 06Z AND LATER. CLEARING
WILL OCCUR WEDNESDAY MORNING AS THE WIND INCREASES TO THE BREEZY
CATEGORY AND THEN DECREASES BY EARLY EVENING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...032
AREA FORECAST DISCUSSION
NWS TOPEKA KS
524 PM CST TUE JAN 15 2013
...UPDATE TO AVIATION...
.DISCUSSION...
20Z WATER VAPOR SHOWS THE TROUGH AXIS OVERHEAD WITH THE UPPER
FLOW BEGINNING TO SPLIT WITH ENERGY BEING LEFT BEHIND OVER THE
SOUTHERN HIGH PLAINS. AT THE SURFACE...THE RIDGE AXIS STRETCHED
FROM THE TX PANHANDLE UP TO CHICAGO. THERE IS A MAXIMUM IN SURFACE
DEWPOINTS IMMEDIATELY DOWNSTREAM OF THE SNOW PACK IN SOUTHERN NEB.
WITH DAYTIME HEATING STEEPENING UP LOW LEVEL LAPSE RATES WITH
ADDED BOUNDARY LAYER MOISTURE...A CU FIELD HAS FORMED OVER NORTH
CENTRAL KS. WOULD EXPECT THESE CLOUDS TO DIMINISH WITH THE LOSS OF
DAYTIME HEATING AND THE 19Z RAP AND 18Z NAM SEEM TO SUPPORT THIS
IDEA...SO THINK SKIES SHOULD BECOME MOSTLY CLEAR OVERNIGHT.
FOR TONIGHT AND WEDNESDAY...THE FORECAST AREA IS EXPECTED TO BE
BETWEEN THE SPLITTING PATTERN WITH A CLOSED LOW REMAINING OVER THE
SOUTHERN PLAINS AND STRONG NORTHWEST FLOW REMAINING NORTH OVER THE
DAKOTAS AND UPPER MIDWEST. THEREFORE THERE IS EXPECTED TO BE LITTLE
OR NOW LARGE SCALE FORCING AFFECTING THE FORECAST AREA. WITH THIS
AND A DRY AIRMASS TO START OUT WITH...THE FORECAST REMAINS DRY.
THERE WILL BE A TROUGH AXIS/WIND SHIFT MOVE THROUGH THE AREA ON
WEDNESDAY. MODELS DO NOT SHOW ANY COLD AIR BEHIND THIS BOUNDARY AND
IN FACT HAVE WARM AIR ADVECTING IN FROM THE WEST WITH A DOWNSLOPE
WIND. THEREFORE HAVE CONTINUED WITH HIGHS GENERALLY AROUND 50. THERE
IS INDICATIONS FROM THE NAM AND GFS OF SOME SATURATED AIR BEHIND THE
FRONT WHICH COULD BE HELPED BY MELTING SNOW IN NEB...SO THINK SKIES
COULD BECOME PARTLY CLOUDY AS WINDS SHIFT TO THE WEST AND NORTHWEST.
THE PRESSURE GRADIENT SHOULD INCREASE OVERNIGHT AS THE SURFACE
TROUGH APPROACHES THE AREA. THIS SHOULD CAUSE WINDS TO GRADUALLY
INCREASE OVERNIGHT HELPING TO KEEP MIN TEMPS SEVERAL DEGREES WARMER
THAN THIS MORNING AND HAVE MIN TEMPS IN THE UPPER TEENS.
WOLTERS
CLEAR SKIES TO BE THE RULE THROUGH EARLY NEXT WEEK WITH NORTHWEST
FLOW ALOFT KEEPING MOISTURE RETURN IN CHECK AND MEAGER FORCING
MECHANISMS FOR CLOUDS LET ALONE PRECIPITATION. WEAK SURFACE HIGH
BUILDS IN THURSDAY WITH ACTUALLY A BIT OF WARMING AROUND
850MB...BUT THE LIMITED MIXING SHOULD KEEP HIGHS A FEW DEGREES
COOLER THAN WEDNESDAY. FRIDAY STILL LOOKING THE BE THE WARMEST DAY
WITH WEST TO SOUTHWEST WINDS DEVELOPING AHEAD OF A WAVE IN THE GREAT
LAKES. SATURDAY WILL SEE THE FIRST OF TWO COLD FRONTS MOVE IN DURING
THE DAY. MID TO LATE DAY COLD AIR ADVECTION SHOULD KEEP HIGHS IN THE
40S...WITH A MORE POTENT SHOT COMING IN THE SUNDAY NIGHT INTO MONDAY
TIME FRAME. THERE HAS BEEN SOME VACILLATION IN THE MODELS WITH HOW
FAR SOUTHWEST THE COLD AIR WILL REACH AND SPECIFIC TIMING OF THE
COLD AIR REMAINS UNCERTAIN. ALSO...THERE IS GOOD AGREEMENT WITH THE
UPPER PATTERN BREAKING DOWN TO A MORE ZONAL CHARACTER AS THE EASTERN
PACIFIC RIDGE BREAKS DOWN LEADING TO THE COLDEST AIR/S RESIDENCE
TIME IN THE CENTRAL PLAINS LIMITED. MONDAYS MAXES IN THE UPPER TEENS
TO MID 20S SEEM REASONABLE AT THIS POINT WITH MODIFICATION FOR
TUESDAY.
65
&&
.AVIATION...
VFR CONDITIONS EXPECTED WITH A SCT OR POSSIBLY BKN DECK AROUND
3000 FEET FOR A FEW HOURS LATE IN THE TAF PERIOD. WILL KEEP
EVERYTHING VFR FOR NOW...AND UPDATE THAT EXPECTATION ON FUTURE
ISSUANCE.
JL
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
233 PM MST MON JAN 14 2013
.SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY)
ISSUED AT 111 PM MST MON JAN 14 2013
CURRENT WV IMAGERY AND RUC H5 ANALYSIS SHOW LARGE TROUGH EXTENDING
FROM CANADA ACROSS THE PLAINS AND SW US TO THE BAJA PENINSULA. MEAN
AXIS IS CURRENTLY UPSTREAM OF CWA ALONG THE CENTRAL ROCKIES WITH
SURFACE TROUGH ALONG FRONT RANGE.
RUC INDICATES AXIS OF H85-H7 FRONTOGENESIS IN PLACE ACROSS EASTERN
COLORADO AND FAR WESTERN KANSAS WHERE LIGHT SNOW HAS BEEN FALLING
FOR MOST OF THE DAY. AS THE UPPER LEVEL TROUGH SHIFTS EAST THIS
EVENING THIS AXIS OF FORCING WILL BEGIN TO WEAKEN AND SHIFT
SOUTH...WITH SNOW COMING TO AN END OVER OUR SW CWA BY 03Z. I
COULD NOT RULE OUT ADDITIONAL SNOW ACCUMULATION AROUND ONE INCH
ALONG AN AXIS FROM STRATTON COLORADO TO BENKELMAN NEBRASKA THROUGH
THIS AFTERNOON WHERE RADAR SHOWS SOME INTENSIFICATION...HOWEVER
MOST LOCATIONS SHOULD SEE LESS THAN ONE HALF INCH TOTAL SNOW
ACCUMULATION FOR THIS EVENT. SUBSIDENCE AND A DRY AIR MASS WILL
BEGIN TO WORK IN OVER THE CWA AFTER MIDNIGHT WITH CLEARING SKIES
FROM THE NORTHWEST OVERNIGHT. THERE WILL BE LITTLE CHANGE IN THE
COLD AIRMASS FROM LAST NIGHT...SO DEPENDING ON HOW QUICKLY
CLOUDS CLEAR WE COULD SEE NEGATIVE TEMPERATURES ONCE AGAIN OVER
PARTS OF THE CWA. FOR NOW I LIMITED COLDEST TEMPS TO THE NORTH AND
WEST WHERE CLOUDS ARE MOST LIKELY TO CLEAR BEFORE SUNRISE.
AIRMASS WILL BEGIN TO MODERATE BY MIDDAY TUESDAY AS LEE TROUGH
DEVELOPS AND WINDS SHIFT TO THE WEST. IT IS A TOUGH CALL ON WHAT
IMPACT LINGERING SNOW PACK WILL HAVE...HOWEVER WE SHOULD SEE
TEMPERATURES IN THE LOW TO MID 30S ACROSS ALL THE CWA...WITH A FEW
LOCATIONS IN THE SOUTH AND EAST POSSIBLY WARMER.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 233 PM MST MON JAN 14 2013
FORECAST PROBLEMS WILL BE AMOUNT OF WARMUP DURING THE EARLY PORTION
OF THIS PERIOD FOLLOWED BY HOW MUCH TO COOL IT DOWN AT THE END OF
THE PERIOD. SATELLITE SHOWING AN AMPLIFIED FLOW STARTING WITH A
BROAD...DEEP AND COMPLICATED UPPER TROUGH OVER THE WESTERN HALF OF
THE PACIFIC WHICH IS MAINTAINING/AMPLIFYING AN UPPER RIDGE NEAR THE
WEST COAST OF NORTH AMERICA. THIS TRANSITIONS TO A TROUGH OVER THE
CENTER OF THE COUNTRY WHICH HAS/CONTINUES TO SPLIT. COLD AIR REMAINS
OVER THE AREA AND UPSTREAM AT THIS TIME.
MODELS INITIALIZED FINE AT JET LEVEL. HOWEVER...THEY WERE A LITTLE
UNDERDONE ON THE SPEEDS BEHIND THE UPPER TROUGH OVER THE COUNTRY.
THE GFS WAS DOING A LITTLE BETTER THAN THE CANADIAN AND NAM. MODELS
INITIALIZED FINE AT MID LEVELS WITH THE ECMWF AND UKMET DOING A
LITTLE BETTER THAN THE GFS AND CANADIAN. THE ECMWF WAS DOING THE
BEST AT THE SURFACE. THE ECMWF WAS DOING A LITTLE BETTER THAN THE
GFS...UKMET AND CANADIAN ON THE LOW LEVEL THERMAL FIELD.
TUESDAY NIGHT/WEDNESDAY...LEFT FRONT QUADRANT OF THE JET MOVES
ACROSS DURING THE NIGHT. UPPER TROUGH WILL HAVE MOVED EAST OF THE
AREA BY THE BEGINNING OF THIS PERIOD. IN ADDITION TO THE LIFT FROM
THE JET...MOISTURE INCREASES THROUGH MID LEVELS ON THE WEST SIDE OF
THE TROUGH. THERE IS SOME MODERATE FRONTOGENESIS AS WELL. LAPSE
RATES ARE NOT THAT GREAT. HOWEVER WITH THE COLD AIR IN PLACE AND THE
MODELS SHOWING DEEP ENOUGH MOISTURE...WILL INSERT FLURRIES INTO
THE NORTHWEST HALF SINCE THE SYNOPTIC LIFT IS NOT THAT GREAT BUT
MESOSCALE FORCING IS PRETTY GOOD. WHATEVER FALLS SHOULD BE DONE BY
06Z.
AFTER THE FLURRIES END...SUBSIDENCE INCREASE BEHIND JET AND UPPER
TROUGH. SO WINDS COULD BECOME BREEZY FROM A DOWNSLOPE DIRECTION FOR
A SHORT PERIOD OF TIME. THIS SHOULD MAKE THE MINS WARMER AND DID
WARM THEM SOME BUT MAYBE NOT ENOUGH. PLENTY OF SUN AND DOWNSLOPE
WINDS SHOULD MAKE FOR A MUCH WARMER DAY THAN WE HAVE BEEN HAVING
LATELY. IN GENERAL...MAXES SHOULD RANGE FROM THE MIDDLE 40S TO NEAR
50 DEGREES.
WEDNESDAY NIGHT/THURSDAY...DOWNSLOPE WINDS SHOULD KEEP MINS WARMER
AGAIN. WILL HAVE PLENTY OF SUN BUT NOT AS FAVORABLE OF A WIND FIELD.
NEW GUIDANCE INDICATES HIGH TEMPERATURES SIMILAR TO WEDNESDAYS AND
DID NOT CHANGE MUCH.
THURSDAY NIGHT THROUGH MONDAY...CURRENT AMPLIFIED PATTERN FLATTENS
OUT A LITTLE BIT EARLY IN THE PERIOD BEFORE BECOMING VERY AMPLIFIED
BY THE END OF THE PERIOD ONCE AGAIN. THROUGH FRIDAY SHOULD MAINTAIN
HIGH TEMPERATURES VERY SIMILAR TO WHAT THEY WERE ON WEDNESDAY AND
THURSDAY. THEN A BIG CHANGE IS GOING TO OCCUR IN TEMPERATURE BUT
WITH UNCERTAINTY IN TIMING AND MAGNITUDE OF THIS TEMPERATURE.
GIVEN WHAT THE PATTERN IS...HAVING A MUCH COLDER AIR MASS INTRUDE
INTO THE REGION IS PRETTY MUCH A GIVEN BUT THE MODELS DISAGREE ON
HOW FAST THEY WHAT TO DO IT. THE GFS AND CANADIAN BRING IN THE
COOLER AIR FASTER WHICH IS FROM LATE SATURDAY AFTERNOON INTO THE
NIGHT. THE 00Z AND 12Z ECMWF PRETTY MUCH KEEP THE COLDER AIR OUT
DURING THE DAY ON SATURDAY. HOWEVER...THE 12Z ECMWF IS MUCH QUICKER
THAN THE OLD RUN IN BRINGING THE COLDER AIR ON SATURDAY NIGHT AND
SUNDAY WHICH A BIG DIFFERENCE ON SUNDAY MAXES. MODELS IN BETTER
AGREEMENT AND MUCH BETTER THAN EARLIER IN BRINGING IN AN ABSOLUTELY
FRIGID AIR MASS SUNDAY NIGHT INTO MONDAY.
THROUGH SATURDAY NIGHT LEFT IN WHAT THE CRH_INIT GAVE ME ALTHOUGH IT
IS POSSIBLE THAT SATURDAY AND SATURDAY NIGHT TEMPERATURES COULD BE
COLDER. FELT PER THE AMPLIFIED PATTERN MAKING THE AREA SUSCEPTIBLE
TO HAVING MUCH COLDER AIR BROUGHT IN...SIGNIFICANT SNOW FIELD OVER
THE NORTH CENTRAL PORTION OF THE COUNTRY...AND MORE MODEL SUPPORT FOR
A SOONER ARRIVING COLD AIR MASS WHICH IS NOT UNCOMMON WITH THIS
MAGNITUDE OF COLD AIR...ADJUSTED THE TEMPERATURES...ESPECIALLY THE
MAXES FOR SUNDAY AND MONDAY...DOWN FROM THE INIT. CONSIDERING THE
AIR MASS WE HAVE HAD IN PLACE FOR THE LAST FEW DAYS AND WHAT THE
MODELS ARE SHOWING...THESE TEMPERATURES WILL PROBABLY NOT BE COLD
ENOUGH...BUT STARTED THE TREND DOWN.
IN REGARDS TO THE PRECIPITATION...LEFT WHAT THE CRH_INIT GAVE ME
WHICH HAS IT DRY DURING THE ENTIRE PERIOD. ALTHOUGH WOULD NOT BE
SURPRISED TO SEE SOME FLURRIES WHEN THE COLD AIR MASS BEGINS TO
ENTER THE AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1028 AM MST MON JAN 14 2013
MAIN AVIATION CONCERN WILL CONTINUE TO BE LIGHT SNOW DURING THE
DAY TODAY AT BOTH KGLD AND KMCK. VFR CONDITIONS SHOULD
PERSIST...THOUGH EITHER TERMINAL MAY BRIEFLY DROP TO MVFR/IFR
BEFORE SNOW TAPERS OF THIS AFTERNOON/EVENING. CONFIDENCE WAS TOO
LOW...AND DUE TO THE INFREQUENCY OF THESE CONDITIONS AT KGLD SO
FAR THIS MORNING I DECIDED AGAINST A TEMPO GROUP DURING THIS
UPDATE. ANY LINGERING SNOW SHOULD END AT KMCK AROUND 00Z...AND BY
03Z AT KGLD. WINDS WOULD REMAIN AT OR BELOW 10KT THROUGH THE
PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
112 PM MST MON JAN 14 2013
.SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY)
ISSUED AT 111 PM MST MON JAN 14 2013
CURRENT WV IMAGERY AND RUC H5 ANALYSIS SHOW LARGE TROUGH EXTENDING
FROM CANADA ACROSS THE PLAINS AND SW US TO THE BAJA PENINSULA. MEAN
AXIS IS CURRENTLY UPSTREAM OF CWA ALONG THE CENTRAL ROCKIES WITH
SURFACE TROUGH ALONG FRONT RANGE.
RUC INDICATES AXIS OF H85-H7 FRONTOGENESIS IN PLACE ACROSS EASTERN
COLORADO AND FAR WESTERN KANSAS WHERE LIGHT SNOW HAS BEEN FALLING
FOR MOST OF THE DAY. AS THE UPPER LEVEL TROUGH SHIFTS EAST THIS
EVENING THIS AXIS OF FORCING WILL BEGIN TO WEAKEN AND SHIFT
SOUTH...WITH SNOW COMING TO AN END OVER OUR SW CWA BY 03Z. I
COULDNT RULE OUT ADDITIONAL SNOW ACCUMULATION AROUND ONE INCH
ALONG AN AXIS FROM STRATTON COLORADO TO BENKELMAN NEBRASKA THROUGH
THIS AFTERNOON WHERE RADAR SHOWS SOME INTENSIFICATION...HOWEVER
MOST LOCATIONS SHOULD SEE LESS THAN ONE HALF INCH TOTAL SNOW
ACCUMULATION FOR THIS EVENT. SUBSIDENCE AND A DRY AIR MASS WILL
BEGIN TO WORK IN OVER THE CWA AFTER MIDNIGHT WITH CLEARING SKIES
FROM THE NORTHWEST OVERNIGHT. THERE WILL BE LITTLE CHANGE IN THE
COLD AIRMASS FROM LAST NIGHT...SO DEPENDING ON HOW QUICKLY
CLOUDS CLEAR WE COULD SEE NEGATIVE TEMPERATURES ONCE AGAIN OVER
PARTS OF THE CWA. FOR NOW I LIMITED COLDEST TEMPS TO THE NORTH AND
WEST WHERE CLOUDS ARE MOST LIKELY TO CLEAR BEFORE SUNRISE.
AIRMASS WILL BEGIN TO MODERATE BY MIDDAY TUESDAY AS LEE TROUGH
DEVELOPS AND WINDS SHIFT TO THE WEST. IT IS A TOUGH CALL ON WHAT
IMPACT LINGERING SNOW PACK WILL HAVE...HOWEVER WE SHOULD SEE
TEMPERATURES IN THE LOW TO MID 30S ACROSS ALL THE CWA...WITH A FEW
LOCATIONS IN THE SOUTH AND EAST POSSIBLY WARMER.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 109 AM MST MON JAN 14 2013
THE PERSISTENT UPPER RIDGE REMAINS OVER THE EASTERN PACIFIC AND
WEST COAST OF THE UNITED STATES THROUGH THE LONG TERM PORTION OF
THE FORECAST. AS A RESULT THE UPPER FLOW OVER THE CENTRAL HIGH
PLAINS REGION REMAINS GENERALLY OUT OF THE NORTHWEST WITH THE
STRONGER NORTHERN BRANCH OF THE UPPER FLOW REMAINING OVER THE
NORTHERN PLAINS THROUGH THE LATTER PORTION OF THE WORK WEEK. THIS
WILL KEEP THE CENTRAL HIGH PLAINS REGION GENERALLY DRY AND WARMER
THAN NORMAL FOR THIS TIME OF YEAR AS ANY OF THE MAJOR DISTURBANCES
MOVING THROUGH THE UPPER FLOW WILL TRACK WELL TO THE NORTH OF THE
FORECAST AREA.
THROUGH THE WEEKEND AND INTO THE BEGINNING OF NEXT WEEK...THE RIDGE
SHARPENS OVER THE WEST COAST AND THE UPPER PATTERN BECOMES MORE
AMPLIFIED WITH THE UPPER FLOW TURNING MORE NORTHERLY OVER THE
ROCKIES AND HIGH PLAINS. THIS WILL ALLOW COLDER AIR TO DIVE DEEPER
TO THE SOUTH THROUGH THE PLAINS STATES WITH TEMPERATURES ACROSS
THE FORECAST AREA RETURNING TO NEAR NORMAL ON SUNDAY AND BECOMING
SLIGHTLY COOLER THAN NORMAL BY MONDAY. THERE IS A LITTLE
PRECIPITATION HINTED AT BY THE GFS ON SUNDAY NIGHT AND MONDAY AS
THE COLDER AIRMASS MOVES IN...BUT HAVE KEPT THE FORECAST DRY FOR
NOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1028 AM MST MON JAN 14 2013
MAIN AVIATION CONCERN WILL CONTINUE TO BE LIGHT SNOW DURING THE
DAY TODAY AT BOTH KGLD AND KMCK. VFR CONDITIONS SHOULD
PERSIST...THOUGH EITHER TERMINAL MAY BRIEFLY DROP TO MVFR/IFR
BEFORE SNOW TAPERS OF THIS AFTERNOON/EVENING. CONFIDENCE WAS TOO
LOW...AND DUE TO THE INFREQUENCY OF THESE CONDITIONS AT KGLD SO
FAR THIS MORNING I DECIDED AGAINST A TEMPO GROUP DURING THIS
UPDATE. ANY LINGERING SNOW SHOULD END AT KMCK AROUND 00Z...AND BY
03Z AT KGLD. WINDS WOULD REMAIN AT OR BELOW 10KT THROUGH THE
PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...DR
AREA FORECAST DISCUSSION
NWS CARIBOU ME
903 AM EST MON JAN 14 2013
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION BY AFTERNOON. MUCH COLDER
TEMPERATURES ARE EXPECTED BEHIND THE FRONT FOR TONIGHT AND
TUESDAY. AFTER A BRIEF RESPITE WEDNESDAY...AN ARCTIC FRONT WILL
CROSS THE REGION THURSDAY AND BRING BITTERLY COLD AIR FOR LATE
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
900 AM UPDATE...ADDED NORTHERN 1/2 OF THE CWA IN A DENSE FOG
ADVISORY THROUGH 11 AM. THIS WILL BE MAINLY ACROSS THE HIGHER TERRAIN.
THE CANADIAN GEM DOING A FINE JOB IN PICKING THE FOG UP AS WELL AS
THE RUC THIS MORNING IN THESE AREAS. DEWPOINTS RISING ALLOW FOR
SOME MELTING OF THE SNOWPACK W/SSE WINDS ACROSS THE NORTH ALLOWING
FOR DENSE FOG.
ACROSS THE CENTRAL AND DOWNEAST AREAS, THE FOG IS BEGINNING TO
LIFT W/VSBYS IMPROVING, SO ADJUSTMENTS HAVE BEEN MADE AND THE
DENSE FOG ADVISORY HAS BEEN ALLOWED TO EXPIRE. SUNSHINE LATER THIS
MORNING INT THE AFTERNOON WILL ALLOW FOR TEMPERATURES IN THESE
AREAS TO WARM IN THE UPPER 40S TO POSSIBLY 50 DEGREES. WE WILL
ASSESS MENTIONED IN THE PREVIOUS DISCUSSION...RAIN SHOWERS HAVE
INDEED BEGUN MOVING INTO CENTRAL AND SOUTHERN PORTIONS OF THE
FORECAST AREA. HAVE INCREASED POPS TO LIKELY IN THESE AREAS. NO
OTHER CHANGES NEEDED.
PREVIOUS DISCUSSION...WIDESPREAD FOG WILL CONTINUE THROUGH THE
EARLY MORNING HOURS AS MOIST SOUTHWEST FLOW STREAMS INTO THE
FORECAST AREA AHEAD OF AN APPROACHING COLD FRONT. WITH VISIBILITY
STILL AT OR BELOW ONE HALF MILE, THE DENSE FOG ADVISORY REMAINS IN
PLACE UNTIL 8 AM FOR DOWNEAST AREAS. UPSTREAM RADARS SHOW RAIN
ASSOCIATED WITH THE FRONT CURRENTLY MOVING INTO NEW YORK. THIS
PRECIPITATION WILL CONTINUE TO PUSH EASTWARD ALONG WITH THE FRONT,
ENTERING NORTHWESTERN MAINE BY AROUND DAYBREAK. THE FRONT WILL
CROSS THE AREA DURING THE MORNING HOURS, MOVING OFFSHORE BY EARLY
AFTERNOON. THEREFORE EXPECT THE RAIN WILL QUICKLY COME TO AN END
SHORTLY AFTER NOON. WHILE THE BULK OF THE PRECIPITATION WILL BE
OVER NORTHERN PORTIONS OF THE FORECAST AREA, HAVE NOTED THAT SOME
OF THE LATEST GUIDANCE, INCLUDING THE 3KM HRRR MODEL, INDICATES
THAT THE RAIN WILL HOLD TOGETHER OVER DOWNEAST MAINE AS WELL. HAVE
THEREFORE BUMPED UP POPS THERE A BIT THROUGH MID-MORNING, BUT THEY
MAY HAVE TO BE INCREASED LATER AS TRENDS BECOME ESTABLISHED.
TEMPERATURES WILL RISE SLIGHTLY THIS MORNING WITH HIGHS RANGING
FROM THE LOWER 40S IN THE NORTH AND WEST TO MID AND UPPER 40S
DOWNEAST. ONCE THE FRONT COMES THROUGH, TEMPERATURES WILL QUICKLY
DROP UNDER BRISK NORTHWEST WINDS.
HIGH PRESSURE WILL SLOWLY BUILD OVER THE REGION TONIGHT. EXPECT
CLEARING SKIES AND DECREASING WINDS. ALTHOUGH OVERNIGHT TEMPS WILL
REMAIN ABOVE NORMAL, IT WILL BE MUCH COLDER THAN READINGS OVER THE
PAST COUPLE OF NIGHTS. LOWS WILL RANGE FROM THE SINGLE DIGITS IN THE
NORTH TO THE UPPER TEENS DOWNEAST. COASTAL AREAS WILL REMAIN IN THE
LOWER 20S.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
FAIR AND COLDER CONDITIONS IS XPCTD TUE INTO TUE NGT AS SEMI-
ARCTIC SFC HI PRES CROSSES THE REGION. RETURN SRLY FLOW WILL OCCUR
ON WED BEHIND THIS HI AS IT MOVES INTO THE MARITIMES. IN THE MEANTIME...
A FLAT S/WV TRACKING ENE FROM SE NEW ENG S OF THE GULF OF ME WILL
BRING DOWNEAST PTNS OF THE FA INCREASING CLDS WED WITH A CHC OF LGT
RN/SN LATE WED INTO WED EVE ALG THE COAST AND MSLY OVR THE ADJACENT
COASTAL WATERS. IMMEDIATELY FOLLOWING THIS SYSTEM....A STRONG
ARCTIC FRONT WILL APCH WRN PTNS OF THE FA LATE WED NGT WITH SOME
CLDNSS AND A CHC OF SN SHWRS. TEMPS WILL BE A LITTLE MILDER ON
WED AND WED NGT WITH THE RETURN SRLY FLOW THAN TUE AND TUE NGT
WHICH WILL FEATURE NEAR SEASONAL TEMPS.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
LONGER RANGE MODELS GENERALLY AGREE WITH MINOR TMG DIFFERENCES THAT
THE ARCTIC FRONT WILL CROSS THE REGION THU MORN...WITH MOST OF
SCT SN SHWRS OVR NW AND FAR NE PTNS OF THE REGION DURING THE
PASSAGE OF THE FRONT. MUCH COLDER TEMPS FOLLOW FOR THU NGT THRU
FRI NGT...WITH HI TEMPS WE SHOW FRI ACROSS THE REGION LIKELY
OPTIMISTIC. HI CLDS COULD BEGIN INCREASING ACROSS OUR REGION FROM
AN ADVCG S/WV FROM THE GREAT LKS AS EARLY AS LATE FRI NGT...BUT
WILL LIKELY HOLD OFF UNTIL SAT.
THE 00Z DTMNSTC GFS AND ECMWF CAME INTO BETTER AGREEMENT WITH THE
TMG OF THE GREAT LKS S/WV...BRINGING OVRRNG SNFL TO THE FA...SPCLY
NRN PTNS SAT NGT INTO SUN. OF THE TWO MODELS...THE GFS ACTUALLY
BRINGS SIG QPF ACROSS THE N HLF OF THE REGION WITH THIS SYSTEM AS
THE SFC TRACKS OVR OR JUST N OF THE FA...WITH LESSER AMTS SHOWN BY
THE ECMWF. FOR NOW...WE WILL INCREASE POPS TO HI CHC FOR STRATIFORM
SN UP TO 50 PERCENT FOR THE N....WITH LESSER POPS CNTRL AND DOWNEAST
AREAS. ANY STEADY SN SHOULD WIND DOWN AS SN SHWRS SUN AFTN AND SUN
NGT BEHIND THIS LOW AS IT MOVES INTO THE CAN MARITIMES...WITH
POTENTIALLY ANOTHER SHOT OF BITTERLY COLD ARCTIC AIR ADVCTG INTO
THE REGION BY LATE SUN NGT INTO MON. WE DO NOT INDICATE THE
POTENTIAL MAGNITUDE OF THIS AIR MASS WITH REGARD TO TEMPS SUN
NGT ATTM DUE TO UNCERTAINTY DUE TO PREVIOUS TMG DIFFERENCES
BETWEEN LONGER RANGE MODELS IN PAST MODEL RUNS...BUT AS WE GET
CLOSER TO THIS EVENT...MORE REALISTIC TEMPS WILL BE SHOWN.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
NEAR TERM: WIDESPREAD IFR WILL CONTINUE THROUGH AT LEAST 13Z-14Z.
WHILE FOG MAY LIFT SOMEWHAT TOWARD DAYBREAK, RAIN ASSOCIATED WITH
A COLD FRONT WILL KEEP CEILINGS IN THE IFR CATEGORY INTO MID-
MORNING. CONDITIONS WILL GRADUALLY IMPROVE THEREAFTER, WITH ALL
SITES REACHING VFR STATUS 18Z-20Z.
SHORT TO LONG TERM: VFR XPCTD...XCPT BRIEF MVFR CONDITIONS
POSSIBLE WITH SN SHWRS ACROSS NRN TAF SITES JUST AHEAD AND DURG
THE PASSAGE OF AN ARCTIC COLD FRONT LATE WED NGT AND THU MORN.
&&
.MARINE...
NEAR TERM: SCA REMAINS IN EFFECT TODAY INTO TONIGHT. A COLD FRONT
WILL MOVE ACROSS THE WATERS LATE THIS MORNING, TURNING SOUTHWEST
WINDS 15 TO 20 KT TO THE NORTHWEST AND INCREASING THEM TO 20 TO 30
KT. THE WINDS WILL SUBSIDE LATER TONIGHT ONCE THE INITIAL COLD
ADVECTION HAS PASSED.
SHORT TO LONG TERM: INITIALLY NO HDLNS TUE INTO WED MORN...THEN
WINDS AND SEAS APCHG AND REACHING SCA CONDITIONS FOR WED AFTN INTO
THUS MORN AHEAD TO JUST BEHIND THE ARCTIC COLD FRONT. CONDITIONS LOWER
BLO SCA CONDITIONS LATER THU INTO THU NGT AND CONT INTO FRI. KEPT
CLOSE TO FCST WW3 GUIDANCE FOR WV HTS.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...DENSE FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR MEZ001>006.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EST TUESDAY FOR ANZ050>052.
&&
$$
NEAR TERM...HASTINGS/HEWITT
SHORT TERM...VJN
LONG TERM...VJN
AVIATION...HASTINGS/HEWITT
MARINE...HASTINGS/HEWITT/VJN
AREA FORECAST DISCUSSION
NWS CARIBOU ME
742 AM EST MON JAN 14 2013
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION BY AFTERNOON. MUCH COLDER
TEMPERATURES ARE EXPECTED BEHIND THE FRONT FOR TONIGHT AND
TUESDAY. AFTER A BRIEF RESPITE WEDNESDAY...AN ARCTIC FRONT WILL
CROSS THE REGION THURSDAY AND BRING BITTERLY COLD AIR FOR LATE
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
520 AM UPDATE...AS MENTIONED IN THE PREVIOUS DISCUSSION...RAIN
SHOWERS HAVE INDEED BEGUN MOVING INTO CENTRAL AND SOUTHERN
PORTIONS OF THE FORECAST AREA. HAVE INCREASED POPS TO LIKELY IN
THESE AREAS. NO OTHER CHANGES NEEDED.
PREVIOUS DISCUSSION...WIDESPREAD FOG WILL CONTINUE THROUGH THE
EARLY MORNING HOURS AS MOIST SOUTHWEST FLOW STREAMS INTO THE
FORECAST AREA AHEAD OF AN APPROACHING COLD FRONT. WITH VISIBILITY
STILL AT OR BELOW ONE HALF MILE, THE DENSE FOG ADVISORY REMAINS IN
PLACE UNTIL 8 AM FOR DOWNEAST AREAS. UPSTREAM RADARS SHOW RAIN
ASSOCIATED WITH THE FRONT CURRENTLY MOVING INTO NEW YORK. THIS
PRECIPITATION WILL CONTINUE TO PUSH EASTWARD ALONG WITH THE FRONT,
ENTERING NORTHWESTERN MAINE BY AROUND DAYBREAK. THE FRONT WILL
CROSS THE AREA DURING THE MORNING HOURS, MOVING OFFSHORE BY EARLY
AFTERNOON. THEREFORE EXPECT THE RAIN WILL QUICKLY COME TO AN END
SHORTLY AFTER NOON. WHILE THE BULK OF THE PRECIPITATION WILL BE
OVER NORTHERN PORTIONS OF THE FORECAST AREA, HAVE NOTED THAT SOME
OF THE LATEST GUIDANCE, INCLUDING THE 3KM HRRR MODEL, INDICATES
THAT THE RAIN WILL HOLD TOGETHER OVER DOWNEAST MAINE AS WELL. HAVE
THEREFORE BUMPED UP POPS THERE A BIT THROUGH MID-MORNING, BUT THEY
MAY HAVE TO BE INCREASED LATER AS TRENDS BECOME ESTABLISHED.
TEMPERATURES WILL RISE SLIGHTLY THIS MORNING WITH HIGHS RANGING
FROM THE LOWER 40S IN THE NORTH AND WEST TO MID AND UPPER 40S
DOWNEAST. ONCE THE FRONT COMES THROUGH, TEMPERATURES WILL QUICKLY
DROP UNDER BRISK NORTHWEST WINDS.
HIGH PRESSURE WILL SLOWLY BUILD OVER THE REGION TONIGHT. EXPECT
CLEARING SKIES AND DECREASING WINDS. ALTHOUGH OVERNIGHT TEMPS WILL
REMAIN ABOVE NORMAL, IT WILL BE MUCH COLDER THAN READINGS OVER THE
PAST COUPLE OF NIGHTS. LOWS WILL RANGE FROM THE SINGLE DIGITS IN THE
NORTH TO THE UPPER TEENS DOWNEAST. COASTAL AREAS WILL REMAIN IN THE
LOWER 20S.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
FAIR AND COLDER CONDITIONS IS XPCTD TUE INTO TUE NGT AS SEMI-
ARCTIC SFC HI PRES CROSSES THE REGION. RETURN SRLY FLOW WILL OCCUR
ON WED BEHIND THIS HI AS IT MOVES INTO THE MARITIMES. IN THE MEANTIME...
A FLAT S/WV TRACKING ENE FROM SE NEW ENG S OF THE GULF OF ME WILL
BRING DOWNEAST PTNS OF THE FA INCREASING CLDS WED WITH A CHC OF LGT
RN/SN LATE WED INTO WED EVE ALG THE COAST AND MSLY OVR THE ADJACENT
COASTAL WATERS. IMMEDIATELY FOLLOWING THIS SYSTEM....A STRONG
ARCTIC FRONT WILL APCH WRN PTNS OF THE FA LATE WED NGT WITH SOME
CLDNSS AND A CHC OF SN SHWRS. TEMPS WILL BE A LITTLE MILDER ON
WED AND WED NGT WITH THE RETURN SRLY FLOW THAN TUE AND TUE NGT
WHICH WILL FEATURE NEAR SEASONAL TEMPS.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
LONGER RANGE MODELS GENERALLY AGREE WITH MINOR TMG DIFFERENCES THAT
THE ARCTIC FRONT WILL CROSS THE REGION THU MORN...WITH MOST OF
SCT SN SHWRS OVR NW AND FAR NE PTNS OF THE REGION DURING THE
PASSAGE OF THE FRONT. MUCH COLDER TEMPS FOLLOW FOR THU NGT THRU
FRI NGT...WITH HI TEMPS WE SHOW FRI ACROSS THE REGION LIKELY
OPTIMISTIC. HI CLDS COULD BEGIN INCREASING ACROSS OUR REGION FROM
AN ADVCG S/WV FROM THE GREAT LKS AS EARLY AS LATE FRI NGT...BUT
WILL LIKELY HOLD OFF UNTIL SAT.
THE 00Z DTMNSTC GFS AND ECMWF CAME INTO BETTER AGREEMENT WITH THE
TMG OF THE GREAT LKS S/WV...BRINGING OVRRNG SNFL TO THE FA...SPCLY
NRN PTNS SAT NGT INTO SUN. OF THE TWO MODELS...THE GFS ACTUALLY
BRINGS SIG QPF ACROSS THE N HLF OF THE REGION WITH THIS SYSTEM AS
THE SFC TRACKS OVR OR JUST N OF THE FA...WITH LESSER AMTS SHOWN BY
THE ECMWF. FOR NOW...WE WILL INCREASE POPS TO HI CHC FOR STRATIFORM
SN UP TO 50 PERCENT FOR THE N....WITH LESSER POPS CNTRL AND DOWNEAST
AREAS. ANY STEADY SN SHOULD WIND DOWN AS SN SHWRS SUN AFTN AND SUN
NGT BEHIND THIS LOW AS IT MOVES INTO THE CAN MARITIMES...WITH
POTENTIALLY ANOTHER SHOT OF BITTERLY COLD ARCTIC AIR ADVCTG INTO
THE REGION BY LATE SUN NGT INTO MON. WE DO NOT INDICATE THE
POTENTIAL MAGNITUDE OF THIS AIR MASS WITH REGARD TO TEMPS SUN
NGT ATTM DUE TO UNCERTAINTY DUE TO PREVIOUS TMG DIFFERENCES
BETWEEN LONGER RANGE MODELS IN PAST MODEL RUNS...BUT AS WE GET
CLOSER TO THIS EVENT...MORE REALISTIC TEMPS WILL BE SHOWN.
&&
.AVIATION /13Z MONDAY THROUGH FRIDAY/...
NEAR TERM: WIDESPREAD IFR WILL CONTINUE THROUGH AT LEAST 13Z-14Z.
WHILE FOG MAY LIFT SOMEWHAT TOWARD DAYBREAK, RAIN ASSOCIATED WITH
A COLD FRONT WILL KEEP CEILINGS IN THE IFR CATEGORY INTO MID-
MORNING. CONDITIONS WILL GRADUALLY IMPROVE THEREAFTER, WITH ALL
SITES REACHING VFR STATUS 18Z-20Z.
SHORT TO LONG TERM: VFR XPCTD...XCPT BRIEF MVFR CONDITIONS
POSSIBLE WITH SN SHWRS ACROSS NRN TAF SITES JUST AHEAD AND DURG
THE PASSAGE OF AN ARCTIC COLD FRONT LATE WED NGT AND THU MORN.
&&
.MARINE...
NEAR TERM: SCA REMAINS IN EFFECT TODAY INTO TONIGHT. A COLD FRONT
WILL MOVE ACROSS THE WATERS LATE THIS MORNING, TURNING SOUTHWEST
WINDS 15 TO 20 KT TO THE NORTHWEST AND INCREASING THEM TO 20 TO 30
KT. THE WINDS WILL SUBSIDE LATER TONIGHT ONCE THE INITIAL COLD
ADVECTION HAS PASSED.
SHORT TO LONG TERM: INITIALLY NO HDLNS TUE INTO WED MORN...THEN
WINDS AND SEAS APCHG AND REACHING SCA CONDITIONS FOR WED AFTN INTO
THUS MORN AHEAD TO JUST BEHIND THE ARCTIC COLD FRONT. CONDITIONS LOWER
BLO SCA CONDITIONS LATER THU INTO THU NGT AND CONT INTO FRI. KEPT
CLOSE TO FCST WW3 GUIDANCE FOR WV HTS.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR MEZ011-
015>017-029>032.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EST TUESDAY FOR ANZ050>052.
&&
$$
NEAR TERM...HASTINGS
SHORT TERM...VJN
LONG TERM...VJN
AVIATION...HASTINGS
MARINE...HASTINGS/VJN
AREA FORECAST DISCUSSION
NWS CARIBOU ME
521 AM EST MON JAN 14 2013
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION BY AFTERNOON. MUCH COLDER
TEMPERATURES ARE EXPECTED BEHIND THE FRONT FOR TONIGHT AND
TUESDAY. AFTER A BRIEF RESPITE WEDNESDAY...AN ARCTIC FRONT WILL
CROSS THE REGION THURSDAY AND BRING BITTERLY COLD AIR FOR LATE
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
520 AM UPDATE...AS MENTIONED IN THE PREVIOUS DISCUSSION...RAIN
SHOWERS HAVE INDEED BEGUN MOVING INTO CENTRAL AND SOUTHERN
PORTIONS OF THE FORECAST AREA. HAVE INCREASED POPS TO LIKELY IN
THESE AREAS. NO OTHER CHANGES NEEDED.
PREVIOUS DISCUSSION...WIDESPREAD FOG WILL CONTINUE THROUGH THE
EARLY MORNING HOURS AS MOIST SOUTHWEST FLOW STREAMS INTO THE
FORECAST AREA AHEAD OF AN APPROACHING COLD FRONT. WITH VISIBILITY
STILL AT OR BELOW ONE HALF MILE, THE DENSE FOG ADVISORY REMAINS IN
PLACE UNTIL 8 AM FOR DOWNEAST AREAS. UPSTREAM RADARS SHOW RAIN
ASSOCIATED WITH THE FRONT CURRENTLY MOVING INTO NEW YORK. THIS
PRECIPITATION WILL CONTINUE TO PUSH EASTWARD ALONG WITH THE FRONT,
ENTERING NORTHWESTERN MAINE BY AROUND DAYBREAK. THE FRONT WILL
CROSS THE AREA DURING THE MORNING HOURS, MOVING OFFSHORE BY EARLY
AFTERNOON. THEREFORE EXPECT THE RAIN WILL QUICKLY COME TO AN END
SHORTLY AFTER NOON. WHILE THE BULK OF THE PRECIPITATION WILL BE
OVER NORTHERN PORTIONS OF THE FORECAST AREA, HAVE NOTED THAT SOME
OF THE LATEST GUIDANCE, INCLUDING THE 3KM HRRR MODEL, INDICATES
THAT THE RAIN WILL HOLD TOGETHER OVER DOWNEAST MAINE AS WELL. HAVE
THEREFORE BUMPED UP POPS THERE A BIT THROUGH MID-MORNING, BUT THEY
MAY HAVE TO BE INCREASED LATER AS TRENDS BECOME ESTABLISHED.
TEMPERATURES WILL RISE SLIGHTLY THIS MORNING WITH HIGHS RANGING
FROM THE LOWER 40S IN THE NORTH AND WEST TO MID AND UPPER 40S
DOWNEAST. ONCE THE FRONT COMES THROUGH, TEMPERATURES WILL QUICKLY
DROP UNDER BRISK NORTHWEST WINDS.
HIGH PRESSURE WILL SLOWLY BUILD OVER THE REGION TONIGHT. EXPECT
CLEARING SKIES AND DECREASING WINDS. ALTHOUGH OVERNIGHT TEMPS WILL
REMAIN ABOVE NORMAL, IT WILL BE MUCH COLDER THAN READINGS OVER THE
PAST COUPLE OF NIGHTS. LOWS WILL RANGE FROM THE SINGLE DIGITS IN THE
NORTH TO THE UPPER TEENS DOWNEAST. COASTAL AREAS WILL REMAIN IN THE
LOWER 20S.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
FAIR AND COLDER CONDITIONS IS XPCTD TUE INTO TUE NGT AS SEMI-
ARCTIC SFC HI PRES CROSSES THE REGION. RETURN SRLY FLOW WILL OCCUR
ON WED BEHIND THIS HI AS IT MOVES INTO THE MARITIMES. IN THE MEANTIME...
A FLAT S/WV TRACKING ENE FROM SE NEW ENG S OF THE GULF OF ME WILL
BRING DOWNEAST PTNS OF THE FA INCREASING CLDS WED WITH A CHC OF LGT
RN/SN LATE WED INTO WED EVE ALG THE COAST AND MSLY OVR THE ADJACENT
COASTAL WATERS. IMMEDIATELY FOLLOWING THIS SYSTEM....A STRONG
ARCTIC FRONT WILL APCH WRN PTNS OF THE FA LATE WED NGT WITH SOME
CLDNSS AND A CHC OF SN SHWRS. TEMPS WILL BE A LITTLE MILDER ON
WED AND WED NGT WITH THE RETURN SRLY FLOW THAN TUE AND TUE NGT
WHICH WILL FEATURE NEAR SEASONAL TEMPS.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
LONGER RANGE MODELS GENERALLY AGREE WITH MINOR TMG DIFFERENCES THAT
THE ARCTIC FRONT WILL CROSS THE REGION THU MORN...WITH MOST OF
SCT SN SHWRS OVR NW AND FAR NE PTNS OF THE REGION DURING THE
PASSAGE OF THE FRONT. MUCH COLDER TEMPS FOLLOW FOR THU NGT THRU
FRI NGT...WITH HI TEMPS WE SHOW FRI ACROSS THE REGION LIKELY
OPTIMISTIC. HI CLDS COULD BEGIN INCREASING ACROSS OUR REGION FROM
AN ADVCG S/WV FROM THE GREAT LKS AS EARLY AS LATE FRI NGT...BUT
WILL LIKELY HOLD OFF UNTIL SAT.
THE 00Z DTMNSTC GFS AND ECMWF CAME INTO BETTER AGREEMENT WITH THE
TMG OF THE GREAT LKS S/WV...BRINGING OVRRNG SNFL TO THE FA...SPCLY
NRN PTNS SAT NGT INTO SUN. OF THE TWO MODELS...THE GFS ACTUALLY
BRINGS SIG QPF ACROSS THE N HLF OF THE REGION WITH THIS SYSTEM AS
THE SFC TRACKS OVR OR JUST N OF THE FA...WITH LESSER AMTS SHOWN BY
THE ECMWF. FOR NOW...WE WILL INCREASE POPS TO HI CHC FOR STRATIFORM
SN UP TO 50 PERCENT FOR THE N....WITH LESSER POPS CNTRL AND DOWNEAST
AREAS. ANY STEADY SN SHOULD WIND DOWN AS SN SHWRS SUN AFTN AND SUN
NGT BEHIND THIS LOW AS IT MOVES INTO THE CAN MARITIMES...WITH
POTENTIALLY ANOTHER SHOT OF BITTERLY COLD ARCTIC AIR ADVCTG INTO
THE REGION BY LATE SUN NGT INTO MON. WE DO NOT INDICATE THE
POTENTIAL MAGNITUDE OF THIS AIR MASS WITH REGARD TO TEMPS SUN
NGT ATTM DUE TO UNCERTAINTY DUE TO PREVIOUS TMG DIFFERENCES
BETWEEN LONGER RANGE MODELS IN PAST MODEL RUNS...BUT AS WE GET
CLOSER TO THIS EVENT...MORE REALISTIC TEMPS WILL BE SHOWN.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
NEAR TERM: WIDESPREAD IFR WILL CONTINUE THROUGH AT LEAST 13Z-14Z.
WHILE FOG MAY LIFT SOMEWHAT TOWARD DAYBREAK, RAIN ASSOCIATED WITH
A COLD FRONT WILL KEEP CEILINGS IN THE IFR CATEGORY INTO MID-
MORNING. CONDITIONS WILL GRADUALLY IMPROVE THEREAFTER, WITH ALL
SITES REACHING VFR STATUS 18Z-20Z.
SHORT TO LONG TERM: VFR XPCTD...XCPT BRIEF MVFR CONDITIONS
POSSIBLE WITH SN SHWRS ACROSS NRN TAF SITES JUST AHEAD AND DURG
THE PASSAGE OF AN ARCTIC COLD FRONT LATE WED NGT AND THU MORN.
&&
.MARINE...
NEAR TERM: SCA REMAINS IN EFFECT TODAY INTO TONIGHT. A COLD FRONT
WILL MOVE ACROSS THE WATERS LATE THIS MORNING, TURNING SOUTHWEST
WINDS 15 TO 20 KT TO THE NORTHWEST AND INCREASING THEM TO 20 TO 30
KT. THE WINDS WILL SUBSIDE LATER TONIGHT ONCE THE INITIAL COLD
ADVECTION HAS PASSED.
SHORT TO LONG TERM: INITIALLY NO HDLNS TUE INTO WED MORN...THEN
WINDS AND SEAS APCHG AND REACHING SCA CONDITIONS FOR WED AFTN INTO
THUS MORN AHEAD TO JUST BEHIND THE ARCTIC COLD FRONT. CONDITIONS LOWER
BLO SCA CONDITIONS LATER THU INTO THU NGT AND CONT INTO FRI. KEPT
CLOSE TO FCST WW3 GUIDANCE FOR WV HTS.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...DENSE FOG ADVISORY UNTIL 8 AM EST THIS MORNING FOR MEZ011-
015>017-029>032.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EST TUESDAY FOR ANZ050>052.
&&
$$
NEAR TERM...HASTINGS
SHORT TERM...VJN
LONG TERM...VJN
AVIATION...HASTINGS
MARINE...HASTINGS/VJN
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1223 PM EST MON JAN 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 535 AM EST MON JAN 14 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL TROUGH
EXTENDING FROM HUDSON BAY THROUGH THE NRN PLAINS INTO THE SW CONUS.
THE SHORTWAVE TROUGH THAT BROUGHT -SN/FLURRIES TO UPPER MI AND
HELPED ENHANCED THE LES INTO THE WEST HAD LIFTED OFF TO THE
NORTHEAST TOWARD QUEBEC. IN ITS WAKE...SHRTWV RIDGING WITH QVECTOR
DIV AND SUBSIDENCE HAS HELPED LIMIT LES INTENSITY OVERNIGHT.
UPSTREAM...ONLY A WEAK SHRTWV WAS NOTED OVER NEBRASKA. AT THE
SFC...A RIDGE EXTENDED FROM SASK THROUGH THE NRN PLAINS INTO THE MID
MS VALLEY RESULTING IN W TO WNW FLOW THROUGH THE NRN GREAT LAKES.
THE LINGERING LAKE INDUCED TROUGH HAS KEPT THE FOCUS OF LES OVER THE
KEWEENAW AND FOR LOCATIONS EAST OF P53.
INSTABILITY FOR LES WILL REMAIN FAVORABLE WITH 850 MB TEMPS NEAR
-19C PRODUCING LAKE INDUCED CAPES IN THE 400-500 J/KG RANGE. THE DGZ
WILL ALSO REMAIN IN THE CONVECTIVE LAYER...LEADING TO HIGH
SNOW/WATER RATIOS IN THE 25/1 TO 30/1 RANGE. UPSTREAM LOW LEVEL
MOISTURE OVER NRN MN WILL HELP MAINTAIN LES ACROSS WRN LAKE
SUPERIOR.
MODELS WERE CONSISTENT IN SUGGESTING THAT LOW LEVEL WINDS WILL
SLOWLY BACK. AS A RESULT...THE LES INTO THE ERN CWA COULD PRODUCE AN
ADDITIONAL 1 TO 3 INCHES BEFORE THE BANDS GRADUALLY SHIFT TOWARD THE
SHORELINE AND MOVE OUT OF THE AREA THIS AFTERNOON. OVER THE WEST...
THE HIGHER RES MODELS SUGGEST THAT THE STRONGEST LES BAND(S) MAINLY
NEAR THE SHORELINE OF ONTONAGON COUNTY TOWARD TWIN LAKES THIS
MORNING WOULD GRADUALLY SHIFT THROUGH NRN HOUGHTON COUNTY TODAY AND
EVENTUALLY TO CMX-P59 TONIGHT. THERE IS LOWER CONFIDENCE WITH THE
SNOWFALL RATES AND AMOUNT OF TIME IT WILL LINGER OVER ANY GIVEN
AREA. THE POTENTIAL REMAINS FOR LOCAL AMOUNTS IN THE 4 TO 8 INCH
RANGE BOTH TODAY AND TONIGHT AS IT LIFTS THROUGH THESE AREAS.
SO...THE LES WARNING WILL CONTINUE AT LEAST UNTIL 12Z/TUE.
OVER THE REST OF THE CWA...EXPECT MAINLY JUST A FEW FLURRIES OVER
THE NORTH OUTSIDE OF THE MAIN LES AREA. EVEN WITH MORE SUNSHINE
TODAY OVER THE SOUTH...TEMPERATURES WILL REMAIN AT OR BELOW NORMAL
FROM 12 TO 17 WEST AND IN THE LOWER 20S EAST. THERE MAY ALSO BE
ENOUGH CLEARING TONIGHT INLAND WITH LIGHT WSW WINDS AS THE RIDGE
BUILDS TOWARD THE REGION TO ALLOW TEMPS TO DIP TO AROUND ZERO.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 535 AM EST MON JAN 14 2013
TUESDAY LOOKS TO BE ONE OF THE FEW BREAKS FROM SNOW FOR MUCH OF THE
LAND CWA...AS WINDS BACK TO THE WEST-SOUTHWEST AHEAD OF AN
APPROACHING SHORTWAVE AND ASSOCIATED COLD FRONT. THIS WILL PUSH
WHAT IS LEFT OF THE BANDS CURRENTLY OVER NORTHERN HOUGHTON AND
KEWEENAW COUNTIES ALONG THE WESTERN SHORELINE DURING THE MORNING
AND THEN OFFSHORE DURING THE AFTERNOON. THE BANDS WILL ALSO BE
DIMINISHING IN INTENSITY DUE TO INCREASING H850 TEMPS.
ELSEWHERE...LOOKS TO BE A FAIRLY NICE DAY WITH ONLY A FEW MID LEVEL
CLOUDS MOVING THROUGH.
HEADING INTO TUESDAY NIGHT...LOOKS LIKE IT COULD BE GUSTY ACROSS
MUCH OF UPPER MICHIGAN AHEAD OF THE COLD FRONT. GALES OVER LAKE
SUPERIOR STILL LOOK LIKELY...SO WILL CONTINUE GALE WATCH. OVER
LAND...INVERSION WILL KEEP MUCH OF THE STRONG 50-60KT LOW LEVEL JET
ALOFT. BUT LATE IN THE NIGHT...THINK IT WILL GET A LITTLE GUSTY AS
THE 10-14MB 6HR PRESSURE FALLS MOVE ACROSS THE CWA. STRONGEST WINDS
WILL LIKELY END UP IN THE SOUTHWEST WIND DOWNSLOPE AREAS NEAR LAKE
SUPERIOR...MAYBE APPROACHING 35-45MPH...WHILE THE REST OF THE AREA
WILL SEE A FEW HOUR PERIOD OF 25-35MPH GUSTS.
THERE IS MUCH BETTER AGREEMENT WITH THE SHORTWAVE AND ASSOCIATED
COLD FRONT THAT MOVES THROUGH LATE TUESDAY NIGHT INTO WEDNESDAY
MORNING. DUE TO THIS...HAVE DELAYED THE START OF THE SNOW INTO THE
OVERNIGHT HOURS. BEST H500 HEIGHT FALLS STAY OVER NORTHERN LAKE
SUPERIOR AND SOUTHERN ONTARIO...BUT DECENT H850-500 Q-VECTOR
CONVERGENCE MOVES OVER THE NORTHERN HALF OF THE CWA. WILL CONTINUE
TO HIGHLIGHT THE HIGHEST POPS OVER THE NORTH HALF OF THE CWA...WITH
CHANCES ELSEWHERE. WITH IT MOVING THROUGH FAIRLY QUICKLY...DON/T
THINK THERE WILL BE TOO MUCH SNOW ACCUMULATION...WITH THE HIGHEST
AMOUNTS OVER THE KEWEENAW AND LUCE COUNTY WHERE THERE COULD BE SOME
ENHANCEMENT OFF LAKE MICHIGAN. THE LEAST AMOUNTS WILL LIKELY BE
OVER THE CENTRAL CWA...WHERE DRY LOW LEVEL AIR WILL LEAD TO SOME
INITIAL EVAPORATION OF THE SNOW. THERE IS A SLIGHT DELAY IN THE
COLD AIR SURGING IN BEHIND THE FRONT...SO AFTER SNOW DIMINISHES ON
WEDNESDAY MORNING AND EARLY AFTERNOON...PROBABLY WONT BE MUCH GOING
ON LAKE EFFECT WISE UNTIL THE COLDER ARRIVES LATE WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT.
BEHIND THE FRONT...PERSISTENT LAKE EFFECT SNOW IS EXPECTED WEDNESDAY
NIGHT THROUGH THURSDAY NIGHT FOR WEST TO NORTHWEST FLOW FAVORED
LOCATIONS. THE AREA WILL BE BETWEEN THE SURFACE LOW ROTATING OVER
HUDSON BAY AND A HIGH PRESSURE IN THE PLAINS STATES. H850 TEMPS
FALLING TO AROUND -24C BEHIND THE FRONT SHOULD PRODUCE SIGNIFICANT
LAKE INSTABILITY DUE TO LAKE SUPERIOR WATER TEMPS AROUND 3C. SINCE
MODELS ARE SHOWING THE INVERSION AROUND 5KFT TO BE FAIRLY
WEAK...LAKE INDUCED EQL LEVELS RISE TO 9-10KFT AND CAPE VALUES
APPROACH 900 J/KG. THESE ARE FAIRLY IMPRESSIVE VALUES...BUT THE
CONCERN WITH SIGNIFICANT SNOWFALL COMES WITH THE BEST MOISTURE
FOCUSED IN THE 2-5KFT RANGE. WITH THE COLD AIR...THE CONVECTIVE
PORTION OF THE LAKE EFFECT SHOULD BE ABOVE THE DGZ AND LEAD TO
MORE COLUMN/PLATE SNOW TYPE...AT LEAST FOR WEDNESDAY NIGHT AND
THURSDAY. THIS WILL LEAD TO LOWER SNOW RATIOS THAN WHAT HAVE BEEN
SEEN OVER THE LAST DAY AND GENERALLY IN THE 15-20 TO 1 RANGE. THE
PERSISTENT NATURE OF THE SNOW DURING THIS PERIOD WILL LIKELY
PRODUCE DECENT LAKE EFFECT SNOW ACCUMULATIONS IN THE FAVORED
LOCATIONS AND WILL CONTINUE TO MENTION PERIODS OF MODERATE SNOW IN
THE HWO. SINCE THE MODELS HAVE BEEN CONSISTENT ON THIS PERIOD OF
LES...WILL MAKE THE JUMP UP TO DEFINITE POPS IN THE WNW TO NW
FAVORED AREAS. TIMING OF SHORTWAVES AND ASSOCIATED POCKETS OF DEEPER
MOISTURE ARE DIFFICULT TO LOCATE/TIME IN NORTHWEST FLOW...BUT THEY
COULD LEAD TO PERIODS OF HEAVY SNOW. THIS WOULD ESPECIALLY BE
TRUE ON THURSDAY AFTERNOON/NIGHT WHEN TEMPS WARM SLIGHTLY TO RAISE
THE DGZ FROM THE SURFACE.
00Z GFS/ECMWF HAVE GOOD CONSISTENCY WITH SHORTWAVE AND CLIPPER
SYSTEM AFFECTING THE AREA ON FRIDAY. CONFIDENCE IN TIMING/LOCATION
STILL IS LOW...BUT THE LATEST TRENDS SUGGEST A BETTER H850 WAA
FOCUS ACROSS THE CWA FOR FRIDAY. THIS WOULD LEAD TO BETTER SNOWFALL
CHANCES /1-2IN OF ACCUM OVER MUCH OF THE CWA/ THAN THE LOW END
CHANCES THAT ARE CURRENTLY IN PLACE. IF MODELS CONTINUE TO SHOW
THIS IDEA...WILL NEED TO BUMP UP POPS.
NORTHWEST FLOW ALOFT WILL CONTINUE INTO THE WEEKEND AS A
UPPER RIDGE BUILDS OVER THE PACIFIC NORTHWEST. BUT MODELS ARE REALLY
STARTING TO DIFFER IN THE UPPER LOW SPINNING EAST OF HUDSON BAY AND
WHAT HAPPENS TO IT THROUGH THE WEEKEND. NO MATTER THE SOLUTION...IT
APPEARS THE AREA WILL STILL BE UNDER THE INFLUENCE OF THE UPPER
TROUGH BUT THERE APPEARS TO BE STRONGER SHORTWAVES DISRUPTING THE
TROUGH SOME. THESE DISRUPTIONS PRODUCES MORE UNCERTAINTY IN THE LOW
TRACK FORECAST...WHICH MAKES THE LOW LEVEL WIND FIELDS HIGHLY
VARIABLE FOR PINNING DOWN LAKE EFFECT AREAS IN ADDITION TO
SYNOPTIC SNOW. WILL FOLLOW A GENERAL MODEL CONSENSUS...WHICH
WILL CONTINUE TO FOCUS THE HIGHEST CHANCE POPS NEAR LAKE SUPERIOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1223 PM EST MON JAN 14 2013
CMX...EXPECT PREDOMINANT MVFR CONDITIONS THRU THIS EVENING IN THE
LAKE EFFECT SNOW SHOWERS AND OBS WILL CONTINUE TO BE HIGHLY VARIABLE
AS BANDS MOVE THROUGH. AS THE FLOW BACKS MORE TO THE WSW...THE
HEAVIER SHSN SHOULD SHIFT TO THE N OF THE SITE LATE TONIGHT.
IWD/SAW...SLOWLY BACKING LLVL FLOW TO THE WSW WL ADVECT DRIER AIR
OVHD AND ALLOW FOR VFR WX THROUGH THE PERIOD. WILL BE A TEMPORARY
MVFR DECK AT IWD WITH LOW LEVEL MOISTURE THIS AFTERNOON MOVING
THROUGH.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 535 AM EST MON JAN 14 2013
NORTHWEST WINDS WILL GRADUALLY BACK TODAY AND TONIGHT...WITH MOST
LOCATIONS SEEING WINDS IN THE 15-25KT RANGE. AS A COLD FRONT
APPROACHES THE AREA ON TUESDAY AND TUESDAY EVENING...SOUTHWEST
WINDS WILL INCREASE TO GALES OF 35-45KTS FOR TUESDAY NIGHT. THEN AS
THE FRONT MOVES THROUGH ON WEDNESDAY MORNING...THE WINDS ARE
EXPECTED TO VEER TO THE NORTHWEST AND STILL PRODUCE GALES TO 40KTS.
THE TIMING OF THE GALE WATCH LOOKS TO BE IN GOOD SHAPE AND WILL
KEEP IT IN PLACE.
NORTHWEST FLOW WILL REMAIN WEDNESDAY NIGHT INTO THURSDAY
NIGHT...WITH WINDS GENERALLY IN THE 15-30KT RANGE WITH A FEW GUSTS
TO 35KTS ON THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 7 AM EST TUESDAY FOR MIZ001-003.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ006-007.
LAKE SUPERIOR...
GALE WATCH FROM TUESDAY AFTERNOON THROUGH WEDNESDAY EVENING FOR
LSZ265>267.
GALE WATCH FROM TUESDAY AFTERNOON THROUGH WEDNESDAY AFTERNOON
FOR LSZ162-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...07
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
652 AM EST MON JAN 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 535 AM EST MON JAN 14 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL TROUGH
EXTENDING FROM HUDSON BAY THROUGH THE NRN PLAINS INTO THE SW CONUS.
THE SHORTWAVE TROUGH THAT BROUGHT -SN/FLURRIES TO UPPER MI AND
HELPED ENHANCED THE LES INTO THE WEST HAD LIFTED OFF TO THE
NORTHEAST TOWARD QUEBEC. IN ITS WAKE...SHRTWV RIDGING WITH QVECTOR
DIV AND SUBSIDENCE HAS HELPED LIMIT LES INTENSITY OVERNIGHT.
UPSTREAM...ONLY A WEAK SHRTWV WAS NOTED OVER NEBRASKA. AT THE
SFC...A RIDGE EXTENDED FROM SASK THROUGH THE NRN PLAINS INTO THE MID
MS VALLEY RESULTING IN W TO WNW FLOW THROUGH THE NRN GREAT LAKES.
THE LINGERING LAKE INDUCED TROUGH HAS KEPT THE FOCUS OF LES OVER THE
KEWEENAW AND FOR LOCATIONS EAST OF P53.
INSTABILITY FOR LES WILL REMAIN FAVORABLE WITH 850 MB TEMPS NEAR
-19C PRODUCING LAKE INDUCED CAPES IN THE 400-500 J/KG RANGE. THE DGZ
WILL ALSO REMAIN IN THE CONVECTIVE LAYER...LEADING TO HIGH
SNOW/WATER RATIOS IN THE 25/1 TO 30/1 RANGE. UPSTREAM LOW LEVEL
MOISTURE OVER NRN MN WILL HELP MAINTAIN LES ACROSS WRN LAKE
SUPERIOR.
MODELS WERE CONSISTENT IN SUGGESTING THAT LOW LEVEL WINDS WILL
SLOWLY BACK. AS A RESULT...THE LES INTO THE ERN CWA COULD PRODUCE AN
ADDITIONAL 1 TO 3 INCHES BEFORE THE BANDS GRADUALLY SHIFT TOWARD THE
SHORELINE AND MOVE OUT OF THE AREA THIS AFTERNOON. OVER THE WEST...
THE HIGHER RES MODELS SUGGEST THAT THE STRONGEST LES BAND(S) MAINLY
NEAR THE SHORELINE OF ONTONAGON COUNTY TOWARD TWIN LAKES THIS
MORNING WOULD GRADUALLY SHIFT THROUGH NRN HOUGHTON COUNTY TODAY AND
EVENTUALLY TO CMX-P59 TONIGHT. THERE IS LOWER CONFIDENCE WITH THE
SNOWFALL RATES AND AMOUNT OF TIME IT WILL LINGER OVER ANY GIVEN
AREA. THE POTENTIAL REMAINS FOR LOCAL AMOUNTS IN THE 4 TO 8 INCH
RANGE BOTH TODAY AND TONIGHT AS IT LIFTS THROUGH THESE AREAS.
SO...THE LES WARNING WILL CONTINUE AT LEAST UNTIL 12Z/TUE.
OVER THE REST OF THE CWA...EXPECT MAINLY JUST A FEW FLURRIES OVER
THE NORTH OUTSIDE OF THE MAIN LES AREA. EVEN WITH MORE SUNSHINE
TODAY OVER THE SOUTH...TEMPERATURES WILL REMAIN AT OR BELOW NORMAL
FROM 12 TO 17 WEST AND IN THE LOWER 20S EAST. THERE MAY ALSO BE
ENOUGH CLEARING TONIGHT INLAND WITH LIGHT WSW WINDS AS THE RIDGE
BUILDS TOWARD THE REGION TO ALLOW TEMPS TO DIP TO AROUND ZERO.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 535 AM EST MON JAN 14 2013
TUESDAY LOOKS TO BE ONE OF THE FEW BREAKS FROM SNOW FOR MUCH OF THE
LAND CWA...AS WINDS BACK TO THE WEST-SOUTHWEST AHEAD OF AN
APPROACHING SHORTWAVE AND ASSOCIATED COLD FRONT. THIS WILL PUSH
WHAT IS LEFT OF THE BANDS CURRENTLY OVER NORTHERN HOUGHTON AND
KEWEENAW COUNTIES ALONG THE WESTERN SHORELINE DURING THE MORNING
AND THEN OFFSHORE DURING THE AFTERNOON. THE BANDS WILL ALSO BE
DIMINISHING IN INTENSITY DUE TO INCREASING H850 TEMPS.
ELSEWHERE...LOOKS TO BE A FAIRLY NICE DAY WITH ONLY A FEW MID LEVEL
CLOUDS MOVING THROUGH.
HEADING INTO TUESDAY NIGHT...LOOKS LIKE IT COULD BE GUSTY ACROSS
MUCH OF UPPER MICHIGAN AHEAD OF THE COLD FRONT. GALES OVER LAKE
SUPERIOR STILL LOOK LIKELY...SO WILL CONTINUE GALE WATCH. OVER
LAND...INVERSION WILL KEEP MUCH OF THE STRONG 50-60KT LOW LEVEL JET
ALOFT. BUT LATE IN THE NIGHT...THINK IT WILL GET A LITTLE GUSTY AS
THE 10-14MB 6HR PRESSURE FALLS MOVE ACROSS THE CWA. STRONGEST WINDS
WILL LIKELY END UP IN THE SOUTHWEST WIND DOWNSLOPE AREAS NEAR LAKE
SUPERIOR...MAYBE APPROACHING 35-45MPH...WHILE THE REST OF THE AREA
WILL SEE A FEW HOUR PERIOD OF 25-35MPH GUSTS.
THERE IS MUCH BETTER AGREEMENT WITH THE SHORTWAVE AND ASSOCIATED
COLD FRONT THAT MOVES THROUGH LATE TUESDAY NIGHT INTO WEDNESDAY
MORNING. DUE TO THIS...HAVE DELAYED THE START OF THE SNOW INTO THE
OVERNIGHT HOURS. BEST H500 HEIGHT FALLS STAY OVER NORTHERN LAKE
SUPERIOR AND SOUTHERN ONTARIO...BUT DECENT H850-500 Q-VECTOR
CONVERGENCE MOVES OVER THE NORTHERN HALF OF THE CWA. WILL CONTINUE
TO HIGHLIGHT THE HIGHEST POPS OVER THE NORTH HALF OF THE CWA...WITH
CHANCES ELSEWHERE. WITH IT MOVING THROUGH FAIRLY QUICKLY...DON/T
THINK THERE WILL BE TOO MUCH SNOW ACCUMULATION...WITH THE HIGHEST
AMOUNTS OVER THE KEWEENAW AND LUCE COUNTY WHERE THERE COULD BE SOME
ENHANCEMENT OFF LAKE MICHIGAN. THE LEAST AMOUNTS WILL LIKELY BE
OVER THE CENTRAL CWA...WHERE DRY LOW LEVEL AIR WILL LEAD TO SOME
INITIAL EVAPORATION OF THE SNOW. THERE IS A SLIGHT DELAY IN THE
COLD AIR SURGING IN BEHIND THE FRONT...SO AFTER SNOW DIMINISHES ON
WEDNESDAY MORNING AND EARLY AFTERNOON...PROBABLY WONT BE MUCH GOING
ON LAKE EFFECT WISE UNTIL THE COLDER ARRIVES LATE WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT.
BEHIND THE FRONT...PERSISTENT LAKE EFFECT SNOW IS EXPECTED WEDNESDAY
NIGHT THROUGH THURSDAY NIGHT FOR WEST TO NORTHWEST FLOW FAVORED
LOCATIONS. THE AREA WILL BE BETWEEN THE SURFACE LOW ROTATING OVER
HUDSON BAY AND A HIGH PRESSURE IN THE PLAINS STATES. H850 TEMPS
FALLING TO AROUND -24C BEHIND THE FRONT SHOULD PRODUCE SIGNIFICANT
LAKE INSTABILITY DUE TO LAKE SUPERIOR WATER TEMPS AROUND 3C. SINCE
MODELS ARE SHOWING THE INVERSION AROUND 5KFT TO BE FAIRLY
WEAK...LAKE INDUCED EQL LEVELS RISE TO 9-10KFT AND CAPE VALUES
APPROACH 900 J/KG. THESE ARE FAIRLY IMPRESSIVE VALUES...BUT THE
CONCERN WITH SIGNIFICANT SNOWFALL COMES WITH THE BEST MOISTURE
FOCUSED IN THE 2-5KFT RANGE. WITH THE COLD AIR...THE CONVECTIVE
PORTION OF THE LAKE EFFECT SHOULD BE ABOVE THE DGZ AND LEAD TO
MORE COLUMN/PLATE SNOW TYPE...AT LEAST FOR WEDNESDAY NIGHT AND
THURSDAY. THIS WILL LEAD TO LOWER SNOW RATIOS THAN WHAT HAVE BEEN
SEEN OVER THE LAST DAY AND GENERALLY IN THE 15-20 TO 1 RANGE. THE
PERSISTENT NATURE OF THE SNOW DURING THIS PERIOD WILL LIKELY
PRODUCE DECENT LAKE EFFECT SNOW ACCUMULATIONS IN THE FAVORED
LOCATIONS AND WILL CONTINUE TO MENTION PERIODS OF MODERATE SNOW IN
THE HWO. SINCE THE MODELS HAVE BEEN CONSISTENT ON THIS PERIOD OF
LES...WILL MAKE THE JUMP UP TO DEFINITE POPS IN THE WNW TO NW
FAVORED AREAS. TIMING OF SHORTWAVES AND ASSOCIATED POCKETS OF DEEPER
MOISTURE ARE DIFFICULT TO LOCATE/TIME IN NORTHWEST FLOW...BUT THEY
COULD LEAD TO PERIODS OF HEAVY SNOW. THIS WOULD ESPECIALLY BE
TRUE ON THURSDAY AFTERNOON/NIGHT WHEN TEMPS WARM SLIGHTLY TO RAISE
THE DGZ FROM THE SURFACE.
00Z GFS/ECMWF HAVE GOOD CONSISTENCY WITH SHORTWAVE AND CLIPPER
SYSTEM AFFECTING THE AREA ON FRIDAY. CONFIDENCE IN TIMING/LOCATION
STILL IS LOW...BUT THE LATEST TRENDS SUGGEST A BETTER H850 WAA
FOCUS ACROSS THE CWA FOR FRIDAY. THIS WOULD LEAD TO BETTER SNOWFALL
CHANCES /1-2IN OF ACCUM OVER MUCH OF THE CWA/ THAN THE LOW END
CHANCES THAT ARE CURRENTLY IN PLACE. IF MODELS CONTINUE TO SHOW
THIS IDEA...WILL NEED TO BUMP UP POPS.
NORTHWEST FLOW ALOFT WILL CONTINUE INTO THE WEEKEND AS A
UPPER RIDGE BUILDS OVER THE PACIFIC NORTHWEST. BUT MODELS ARE REALLY
STARTING TO DIFFER IN THE UPPER LOW SPINNING EAST OF HUDSON BAY AND
WHAT HAPPENS TO IT THROUGH THE WEEKEND. NO MATTER THE SOLUTION...IT
APPEARS THE AREA WILL STILL BE UNDER THE INFLUENCE OF THE UPPER
TROUGH BUT THERE APPEARS TO BE STRONGER SHORTWAVES DISRUPTING THE
TROUGH SOME. THESE DISRUPTIONS PRODUCES MORE UNCERTAINTY IN THE LOW
TRACK FORECAST...WHICH MAKES THE LOW LEVEL WIND FIELDS HIGHLY
VARIABLE FOR PINNING DOWN LAKE EFFECT AREAS IN ADDITION TO
SYNOPTIC SNOW. WILL FOLLOW A GENERAL MODEL CONSENSUS...WHICH
WILL CONTINUE TO FOCUS THE HIGHEST CHANCE POPS NEAR LAKE SUPERIOR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 638 AM EST MON JAN 14 2013
CMX...EXPECT PREDOMINANT IFR CONDITIONS THRU TODAY WITH PERSISTENT/
UPSLOPE WNW FLOW AND SUFFICIENT INSTABILITY FOR LES. THE BEST CHC
FOR LIFR WX WL BE 15Z-21Z TODAY...WHEN AXIS OF ENHANCED LOW LEVEL
CONVERGENCE ASSOCIATED WITH SLOWLY BACKING LARGER SCALE FLOW WL
SHIFT OVHD. HOWEVER...CONFIDENCE IN THE TIMING AND STRENGTH OF THE
BAND IS MARGINAL. AS THE FLOW BACKS MORE TO THE WSW...THE HEAVIER
SHSN SHOULD SHIFT TO THE N OF THE SITE AND ALLOW A RETURN OF
PREDOMINANT MVFR CONDITIONS AND LIGHTER -SHSN.
IWD/SAW...ALTHOUGH SOME MVFR CONDITIONS MIGHT IMPACT THESE SITES
EARLY IN THE PERIOD...A SLOWLY BACKING LLVL FLOW TOWARD THE WSW WL
ADVECT DRIER AIR OVHD AND ALLOW FOR MAINLY VFR WX.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 535 AM EST MON JAN 14 2013
NORTHWEST WINDS WILL GRADUALLY BACK TODAY AND TONIGHT...WITH MOST
LOCATIONS SEEING WINDS IN THE 15-25KT RANGE. AS A COLD FRONT
APPROACHES THE AREA ON TUESDAY AND TUESDAY EVENING...SOUTHWEST
WINDS WILL INCREASE TO GALES OF 35-45KTS FOR TUESDAY NIGHT. THEN AS
THE FRONT MOVES THROUGH ON WEDNESDAY MORNING...THE WINDS ARE
EXPECTED TO VEER TO THE NORTHWEST AND STILL PRODUCE GALES TO 40KTS.
THE TIMING OF THE GALE WATCH LOOKS TO BE IN GOOD SHAPE AND WILL
KEEP IT IN PLACE.
NORTHWEST FLOW WILL REMAIN WEDNESDAY NIGHT INTO THURSDAY
NIGHT...WITH WINDS GENERALLY IN THE 15-30KT RANGE WITH A FEW GUSTS
TO 35KTS ON THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 7 AM EST TUESDAY FOR MIZ001-003.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THIS MORNING FOR MIZ002.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ006-007.
LAKE SUPERIOR...
GALE WATCH FROM TUESDAY AFTERNOON THROUGH WEDNESDAY EVENING FOR
LSZ265>267.
GALE WATCH FROM TUESDAY AFTERNOON THROUGH WEDNESDAY AFTERNOON
FOR LSZ162-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...JLB
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
536 AM EST MON JAN 14 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 535 AM EST MON JAN 14 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL TROUGH
EXTENDING FROM HUDSON BAY THROUGH THE NRN PLAINS INTO THE SW CONUS.
THE SHORTWAVE TROUGH THAT BROUGHT -SN/FLURRIES TO UPPER MI AND
HELPED ENHANCED THE LES INTO THE WEST HAD LIFTED OFF TO THE
NORTHEAST TOWARD QUEBEC. IN ITS WAKE...SHRTWV RIDGING WITH QVECTOR
DIV AND SUBSIDENCE HAS HELPED LIMIT LES INTENSITY OVERNIGHT.
UPSTREAM...ONLY A WEAK SHRTWV WAS NOTED OVER NEBRASKA. AT THE
SFC...A RIDGE EXTENDED FROM SASK THROUGH THE NRN PLAINS INTO THE MID
MS VALLEY RESULTING IN W TO WNW FLOW THROUGH THE NRN GREAT LAKES.
THE LINGERING LAKE INDUCED TROUGH HAS KEPT THE FOCUS OF LES OVER THE
KEWEENAW AND FOR LOCATIONS EAST OF P53.
INSTABILITY FOR LES WILL REMAIN FAVORABLE WITH 850 MB TEMPS NEAR
-19C PRODUCING LAKE INDUCED CAPES IN THE 400-500 J/KG RANGE. THE DGZ
WILL ALSO REMAIN IN THE CONVECTIVE LAYER...LEADING TO HIGH
SNOW/WATER RATIOS IN THE 25/1 TO 30/1 RANGE. UPSTREAM LOW LEVEL
MOISTURE OVER NRN MN WILL HELP MAINTAIN LES ACROSS WRN LAKE
SUPERIOR.
MODELS WERE CONSISTENT IN SUGGESTING THAT LOW LEVEL WINDS WILL
SLOWLY BACK. AS A RESULT...THE LES INTO THE ERN CWA COULD PRODUCE AN
ADDITIONAL 1 TO 3 INCHES BEFORE THE BANDS GRADUALLY SHIFT TOWARD THE
SHORELINE AND MOVE OUT OF THE AREA THIS AFTERNOON. OVER THE WEST...
THE HIGHER RES MODELS SUGGEST THAT THE STRONGEST LES BAND(S) MAINLY
NEAR THE SHORELINE OF ONTONAGON COUNTY TOWARD TWIN LAKES THIS
MORNING WOULD GRADUALLY SHIFT THROUGH NRN HOUGHTON COUNTY TODAY AND
EVENTUALLY TO CMX-P59 TONIGHT. THERE IS LOWER CONFIDENCE WITH THE
SNOWFALL RATES AND AMOUNT OF TIME IT WILL LINGER OVER ANY GIVEN
AREA. THE POTENTIAL REMAINS FOR LOCAL AMOUNTS IN THE 4 TO 8 INCH
RANGE BOTH TODAY AND TONIGHT AS IT LIFTS THROUGH THESE AREAS.
SO...THE LES WARNING WILL CONTINUE AT LEAST UNTIL 12Z/TUE.
OVER THE REST OF THE CWA...EXPECT MAINLY JUST A FEW FLURRIES OVER
THE NORTH OUTSIDE OF THE MAIN LES AREA. EVEN WITH MORE SUNSHINE
TODAY OVER THE SOUTH...TEMPERATURES WILL REMAIN AT OR BELOW NORMAL
FROM 12 TO 17 WEST AND IN THE LOWER 20S EAST. THERE MAY ALSO BE
ENOUGH CLEARING TONIGHT INLAND WITH LIGHT WSW WINDS AS THE RIDGE
BUILDS TOWARD THE REGION TO ALLOW TEMPS TO DIP TO AROUND ZERO.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 535 AM EST MON JAN 14 2013
TUESDAY LOOKS TO BE ONE OF THE FEW BREAKS FROM SNOW FOR MUCH OF THE
LAND CWA...AS WINDS BACK TO THE WEST-SOUTHWEST AHEAD OF AN
APPROACHING SHORTWAVE AND ASSOCIATED COLD FRONT. THIS WILL PUSH
WHAT IS LEFT OF THE BANDS CURRENTLY OVER NORTHERN HOUGHTON AND
KEWEENAW COUNTIES ALONG THE WESTERN SHORELINE DURING THE MORNING
AND THEN OFFSHORE DURING THE AFTERNOON. THE BANDS WILL ALSO BE
DIMINISHING IN INTENSITY DUE TO INCREASING H850 TEMPS.
ELSEWHERE...LOOKS TO BE A FAIRLY NICE DAY WITH ONLY A FEW MID LEVEL
CLOUDS MOVING THROUGH.
HEADING INTO TUESDAY NIGHT...LOOKS LIKE IT COULD BE GUSTY ACROSS
MUCH OF UPPER MICHIGAN AHEAD OF THE COLD FRONT. GALES OVER LAKE
SUPERIOR STILL LOOK LIKELY...SO WILL CONTINUE GALE WATCH. OVER
LAND...INVERSION WILL KEEP MUCH OF THE STRONG 50-60KT LOW LEVEL JET
ALOFT. BUT LATE IN THE NIGHT...THINK IT WILL GET A LITTLE GUSTY AS
THE 10-14MB 6HR PRESSURE FALLS MOVE ACROSS THE CWA. STRONGEST WINDS
WILL LIKELY END UP IN THE SOUTHWEST WIND DOWNSLOPE AREAS NEAR LAKE
SUPERIOR...MAYBE APPROACHING 35-45MPH...WHILE THE REST OF THE AREA
WILL SEE A FEW HOUR PERIOD OF 25-35MPH GUSTS.
THERE IS MUCH BETTER AGREEMENT WITH THE SHORTWAVE AND ASSOCIATED
COLD FRONT THAT MOVES THROUGH LATE TUESDAY NIGHT INTO WEDNESDAY
MORNING. DUE TO THIS...HAVE DELAYED THE START OF THE SNOW INTO THE
OVERNIGHT HOURS. BEST H500 HEIGHT FALLS STAY OVER NORTHERN LAKE
SUPERIOR AND SOUTHERN ONTARIO...BUT DECENT H850-500 Q-VECTOR
CONVERGENCE MOVES OVER THE NORTHERN HALF OF THE CWA. WILL CONTINUE
TO HIGHLIGHT THE HIGHEST POPS OVER THE NORTH HALF OF THE CWA...WITH
CHANCES ELSEWHERE. WITH IT MOVING THROUGH FAIRLY QUICKLY...DON/T
THINK THERE WILL BE TOO MUCH SNOW ACCUMULATION...WITH THE HIGHEST
AMOUNTS OVER THE KEWEENAW AND LUCE COUNTY WHERE THERE COULD BE SOME
ENHANCEMENT OFF LAKE MICHIGAN. THE LEAST AMOUNTS WILL LIKELY BE
OVER THE CENTRAL CWA...WHERE DRY LOW LEVEL AIR WILL LEAD TO SOME
INITIAL EVAPORATION OF THE SNOW. THERE IS A SLIGHT DELAY IN THE
COLD AIR SURGING IN BEHIND THE FRONT...SO AFTER SNOW DIMINISHES ON
WEDNESDAY MORNING AND EARLY AFTERNOON...PROBABLY WONT BE MUCH GOING
ON LAKE EFFECT WISE UNTIL THE COLDER ARRIVES LATE WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT.
BEHIND THE FRONT...PERSISTENT LAKE EFFECT SNOW IS EXPECTED WEDNESDAY
NIGHT THROUGH THURSDAY NIGHT FOR WEST TO NORTHWEST FLOW FAVORED
LOCATIONS. THE AREA WILL BE BETWEEN THE SURFACE LOW ROTATING OVER
HUDSON BAY AND A HIGH PRESSURE IN THE PLAINS STATES. H850 TEMPS
FALLING TO AROUND -24C BEHIND THE FRONT SHOULD PRODUCE SIGNIFICANT
LAKE INSTABILITY DUE TO LAKE SUPERIOR WATER TEMPS AROUND 3C. SINCE
MODELS ARE SHOWING THE INVERSION AROUND 5KFT TO BE FAIRLY
WEAK...LAKE INDUCED EQL LEVELS RISE TO 9-10KFT AND CAPE VALUES
APPROACH 900 J/KG. THESE ARE FAIRLY IMPRESSIVE VALUES...BUT THE
CONCERN WITH SIGNIFICANT SNOWFALL COMES WITH THE BEST MOISTURE
FOCUSED IN THE 2-5KFT RANGE. WITH THE COLD AIR...THE CONVECTIVE
PORTION OF THE LAKE EFFECT SHOULD BE ABOVE THE DGZ AND LEAD TO
MORE COLUMN/PLATE SNOW TYPE...AT LEAST FOR WEDNESDAY NIGHT AND
THURSDAY. THIS WILL LEAD TO LOWER SNOW RATIOS THAN WHAT HAVE BEEN
SEEN OVER THE LAST DAY AND GENERALLY IN THE 15-20 TO 1 RANGE. THE
PERSISTENT NATURE OF THE SNOW DURING THIS PERIOD WILL LIKELY
PRODUCE DECENT LAKE EFFECT SNOW ACCUMULATIONS IN THE FAVORED
LOCATIONS AND WILL CONTINUE TO MENTION PERIODS OF MODERATE SNOW IN
THE HWO. SINCE THE MODELS HAVE BEEN CONSISTENT ON THIS PERIOD OF
LES...WILL MAKE THE JUMP UP TO DEFINITE POPS IN THE WNW TO NW
FAVORED AREAS. TIMING OF SHORTWAVES AND ASSOCIATED POCKETS OF DEEPER
MOISTURE ARE DIFFICULT TO LOCATE/TIME IN NORTHWEST FLOW...BUT THEY
COULD LEAD TO PERIODS OF HEAVY SNOW. THIS WOULD ESPECIALLY BE
TRUE ON THURSDAY AFTERNOON/NIGHT WHEN TEMPS WARM SLIGHTLY TO RAISE
THE DGZ FROM THE SURFACE.
00Z GFS/ECMWF HAVE GOOD CONSISTENCY WITH SHORTWAVE AND CLIPPER
SYSTEM AFFECTING THE AREA ON FRIDAY. CONFIDENCE IN TIMING/LOCATION
STILL IS LOW...BUT THE LATEST TRENDS SUGGEST A BETTER H850 WAA
FOCUS ACROSS THE CWA FOR FRIDAY. THIS WOULD LEAD TO BETTER SNOWFALL
CHANCES /1-2IN OF ACCUM OVER MUCH OF THE CWA/ THAN THE LOW END
CHANCES THAT ARE CURRENTLY IN PLACE. IF MODELS CONTINUE TO SHOW
THIS IDEA...WILL NEED TO BUMP UP POPS.
NORTHWEST FLOW ALOFT WILL CONTINUE INTO THE WEEKEND AS A
UPPER RIDGE BUILDS OVER THE PACIFIC NORTHWEST. BUT MODELS ARE REALLY
STARTING TO DIFFER IN THE UPPER LOW SPINNING EAST OF HUDSON BAY AND
WHAT HAPPENS TO IT THROUGH THE WEEKEND. NO MATTER THE SOLUTION...IT
APPEARS THE AREA WILL STILL BE UNDER THE INFLUENCE OF THE UPPER
TROUGH BUT THERE APPEARS TO BE STRONGER SHORTWAVES DISRUPTING THE
TROUGH SOME. THESE DISRUPTIONS PRODUCES MORE UNCERTAINTY IN THE LOW
TRACK FORECAST...WHICH MAKES THE LOW LEVEL WIND FIELDS HIGHLY
VARIABLE FOR PINNING DOWN LAKE EFFECT AREAS IN ADDITION TO
SYNOPTIC SNOW. WILL FOLLOW A GENERAL MODEL CONSENSUS...WHICH
WILL CONTINUE TO FOCUS THE HIGHEST CHANCE POPS NEAR LAKE SUPERIOR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1209 AM EST MON JAN 14 2013
CMX...EXPECT PREDOMINANT IFR CONDITIONS THRU TODAY WITH PERSISTENT/
UPSLOPE WNW FLOW AND SUFFICIENT INSTABILITY FOR LES. THE BEST CHC
FOR LIFR WX WL BE 12Z-18Z TODAY...WHEN AXIS OF ENHANCED LLVL CNVGC
ASSOCIATED WITH SLOWLY BACKING LARGER SCALE FLOW WL SHIFT OVHD. AS
THE FLOW BACKS MORE TO THE WSW...THE HEAVIER SHSN SHOULD SHIFT TO
THE N OF THE SITE AND ALLOW A RETURN OF PREDOMINANT MVFR CONDITIONS/
LIGHTER -SHSN.
IWD/SAW...ALTHOUGH SOME MVFR CONDITIONS MIGHT IMPACT THESE SITES
EARLY IN THE PERIOD...A SLOWLY BACKING LLVL FLOW TOWARD THE WSW WL
ADVECT DRIER AIR OVHD AND ALLOW A RETURN OF PREDOMINANT VFR WX.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 535 AM EST MON JAN 14 2013
NORTHWEST WINDS WILL GRADUALLY BACK TODAY AND TONIGHT...WITH MOST
LOCATIONS SEEING WINDS IN THE 15-25KT RANGE. AS A COLD FRONT
APPROACHES THE AREA ON TUESDAY AND TUESDAY EVENING...SOUTHWEST
WINDS WILL INCREASE TO GALES OF 35-45KTS FOR TUESDAY NIGHT. THEN AS
THE FRONT MOVES THROUGH ON WEDNESDAY MORNING...THE WINDS ARE
EXPECTED TO VEER TO THE NORTHWEST AND STILL PRODUCE GALES TO 40KTS.
THE TIMING OF THE GALE WATCH LOOKS TO BE IN GOOD SHAPE AND WILL
KEEP IT IN PLACE.
NORTHWEST FLOW WILL REMAIN WEDNESDAY NIGHT INTO THURSDAY
NIGHT...WITH WINDS GENERALLY IN THE 15-30KT RANGE WITH A FEW GUSTS
TO 35KTS ON THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 7 AM EST TUESDAY FOR MIZ001-003.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THIS MORNING FOR MIZ002.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ006-007.
LAKE SUPERIOR...
GALE WATCH FROM TUESDAY AFTERNOON THROUGH WEDNESDAY EVENING FOR
LSZ265>267.
GALE WATCH FROM TUESDAY AFTERNOON THROUGH WEDNESDAY AFTERNOON
FOR LSZ162-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...KC
MARINE...SRF
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
426 PM CST MON JAN 14 2013
.UPDATE...
.DISCUSSION...
QUICK UPDATE FOR SOUTHWEST NEBRASKA. THE RUC13 SHOWS AND AREA OF
LIGHT SNOW ON THE 285K INSENTROPIC SFC MOVING EAST THIS EVENING.
THE NEW FORECAST SLOWS THIS DOWN ABOUT 3 HOURS AND RAISES THE POP
TO 50 PERCENT. LESS THAN AN INCH ACCUMULATION IS EXPECTED
ALTHOUGH THE RUC SHOWS 3 INCHES. THE RUC IS OFTEN TOO WET. REST OF
THE FORECAST IS GOOD.
&&
.PREV DISCUSSION... /ISSUED 245 PM CST MON JAN 14 2013/
SYNOPSIS...
IN THE UPPER LEVELS...THE LARGE SCALE CYCLONIC FLOW CONTINUES
OVER A LARGE PART OF THE CENTRAL AND WESTERN U.S. RUNNING A 24 HOUR
LOOP OF THE IMAGERY...ONE CAN SEE THE DIGGING AND NARROWING OF THE
TROUGH. ANALYSIS OF THE 20Z SURFACE DATA REVEALED A WARM FRONT
DEVELOPING ACROSS EASTERN MONTANA AND EASTERN WYOMING.
SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT.
A LOOK AT THE 280-290K LAYER INDICATES SOME WEAK ISENTROPIC LIFT
CONTINUING INTO THIS EVENING IN EXTREME SOUTHWEST NEBRASKA.
HOWEVER...VERY LITTLE MOISTURE AND ACCUMULATIONS WILL BE HALF AN
INCH OR LESS.
FOR TUESDAY...A WARM FRONT IS EXPECTED INTO WESTERN NEBRASKA BY
EARLY EVENING. AGAIN...IN THE 280-290K LAYER...ISENTROPIC UPGLIDE IS
LIKELY TO PRODUCE SOME CLOUDINESS AND POSSIBLY SOME LIGHT SNOW IN
THE EVENING AND LIGHT FREEZING DRIZZLE LATE TUESDAY NIGHT AND VERY
EARLY WEDNESDAY.
MEDIUM RANGE/EXTENDED...WEDNESDAY THROUGH SUNDAY.
DRY AND MUCH WARMER WEATHER CAN BE EXPECTED WEDNESDAY THROUGH
FRIDAY IN THE AFTERMATH OF THE WARM FRONT.
MUCH COLDER WEATHER IS EXPECTED AGAIN AS A BACK-DOOR FRONT COMES
ACROSS SATURDAY NIGHT AND SUNDAY. THE FRONT STALLS ALONG THE EASTERN
SLOPE OF THE ROCKIES AND SOUTHWEST FLOW WILL PRODUCE ISENTROPIC LIFT
AND COULD GIVE SOME POTENTIAL FOR WIDESPREAD SNOW MONDAY AS THE
SYSTEM MAKES ITS WAY BACK TO THE EAST-NORTHEAST. AT THAT RANGE...
THE UNCERTAINTY IS VERY HIGH REGARDING AMOUNTS AND INTENSITY OF
PRECIPITATION.
AVIATION...
FOR THE 18Z TAF FORECAST CYCLE...GENERAL VFR EXPECTED TODAY
ACROSS MOST AREA TERMINALS. THE EXCEPTION BEING ACROSS FAR
SOUTHWEST NEBRASKA TODAY...POSSIBLY AFFECTING THE KOGA AND KIML
TERMINALS WHERE SCATTERED LIGHT SNOW MAY BRIEFLY REDUCE VISIBILITIES
INTO MVFR. MODEL GUIDANCE HAS THE REMAINING LIGHT SNOW DISSIPATING
LATER THIS AFTERNOON...IF NOT ALREADY SO...THEREAFTER DRIER AIR
ALOFT WILL WORK BACK ACROSS THE REGION...WITH NO VISIBILITY OR
CEILING RESTRICTIONS ANTICIPATED. FOR THE OVERNIGHT...NAM SHORT
TERM GUIDANCE HINTS AT REDUCED VISIBILITY /DOWN TO 3SM/ AT KLBF
AFTER 06Z WITH THE FORMATION OF LOW FOG. FEEL THAT THE SOLUTION IS
OVERLY AMBITIOUS WITH THE REMAINING LOW LEVEL MOISTURE...SO WILL NOT
INCLUDE A MENTION OF MVFR VISIBILITY IN THE OFFICIAL TAF FORECAST
NOW. OTHERWISE BROAD SURFACE HIGH PRESSURE WILL KEEP WIND SPEEDS
RELATIVELY LIGHT AND VARIABLE FOR ALL TERMINALS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM/EXTENDED...CDC
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1233 PM EST MON JAN 14 2013
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PRODUCE UNSEASONABLY WARM CONDITIONS
INTO MID-WEEK. A COLD FRONT WILL MOVE SLOWLY THROUGH THE AREA
LATE WEDNESDAY. WEAK GULF COAST LOW PRESSURE MAY BRING A CHANCE OF
LIGHT RAIN TO THE REGION THURSDAY NIGHT OR FRIDAY. HIGH PRESSURE
WILL BUILD IN BEHIND THE COLD FRONT FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM MONDAY...HAVE ADJUSTED TEMPS UP A COUPLE OF DEGREES
FOR TODAY KEEPING MAX TEMPS IN THE MID TO UPPER 70S. THE
SOUTHWESTERLY WINDS WILL BACK A BIT PRODUCING MORE OF AN ON
SHORE FLOW THROUGH THE AFTERNOON. THIS WILL KEEP TEMPS COOLER
ALONG THE SHORE...MOVING INLAND AS WINDS PICK UP THROUGH THE
AFTERNOON. SEA FOG WILL ALSO HELP TO KEEP TEMPS COOLER ALONG THE
COAST.
PREVIOUS DISCUSSION...MODELS INDICATE THE MID TO UPPER LEVEL RIDGE TO
REMAIN ANCHORED JUST OFF THE SE U.S. COAST DURING THIS NEAR TERM
PERIOD. THIS WILL SLOW DOWN THE PROGRESSION OF THE BAROCLINIC ZONE
IE. THE SFC COLD FRONT...TOWARD THE SOUTHEAST. IN FACT... MODELS
ACTUALLY STALL THE COLD FRONT JUST NORTH AND WEST OF THE FA AS IT
BECOMES ORIENTED PARALLEL WITH THE FLOW ALOFT. THE DEEPEST
MOISTURE WILL REMAIN JUST OUTSIDE OF THE ILM CWA DURING THIS NEAR
TERM PERIOD...REMAINING WEST THROUGH NORTH OF THE FA. AMAZINGLY...
GFS/NAM/EUROPEAN/ETC. AGREE THAT THIS SCENARIO WILL PLAY OUT. NOW
WHAT THEY DO NOT AGREE IS THE THREAT OR PROBABILITY FOR PCPN. WITH
THE BEST LIFT REMAINING OUTSIDE OF THE ILM CWA DOMAIN...HAVE
INDICATED A LOW CHANCE OF POPS FOR THE NW PORTIONS OF THE FA FROM
THIS AFTERNOON THROUGH TONIGHT...ROUGHLY ALONG AND WEST OF THE
I-95 CORRIDOR. THE LATEST RUN OF THE HRRR MODEL ALSO INDICATES
THIS PCPN POSSIBILITY. HAVE STAYED AWAY FROM MENTIONING THUNDER
DUE TO THE LACK OF INSTABILITY ILLUSTRATED BY LATEST NAMBUFR
SOUNDINGS...IE. NO CAPE...LI`S STAY MAINLY POSITIVE. WILL LIKELY
HAVE A SOMEWHAT OF A SHARP CLOUD GRADIENT ACROSS THE FA WITH THE
IMMEDIATE COAST HAVING THE BEST POTENTIAL TO OBSERVE THE DAYS
INSOLATION. THEREFORE...HAVE RELIED ON THE WARMER MODEL MOS
GUIDANCE FOR BOTH TODAYS MAX AND TONIGHTS MIN TEMPS. THIS WILL
RESULT IN ADDITIONAL MAX TEMP RECORDS LIKELY BEING SET FOR 1 MORE
DAY. AND FINALLY...THE MID TO UPPER LEVEL CLOUD DECK ACROSS THE FA
HAS BEEN OPAQUE ENOUGH TO PREVENT WIDESPREAD RADIATIONAL TYPE
DENSE FOG. HOWEVER...SEA FOG IE. ADVECTION TYPE FOG...WILL
SPORADICALLY AFFECT THE IMMEDIATE COAST AS SFC WINDS SLIGHTLY BACK
TO THE SSW AND PUSH 60+ DEWPOINTS ACROSS SSTS IN THE 50S RESULTING
WITH SEA FOG BRIEFLY PUSHING ONSHORE AT TIMES.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 245 AM MONDAY...WEAK FRONT WILL BE STALLED IN OR JUST WEST
OF THE REGION FOR A MAJORITY OF THE PERIOD. PROXIMITY TO FRONT
WILL CREATE SIGNIFICANT TEMP GRADIENT ACROSS THE
REGION...PROVIDING PLENTY OF POTENTIAL FOR THE FORECAST TO GO
WRONG. SOME WEAK ISENTROPIC LIFT AND LOW LEVEL MOISTURE MAY
PRODUCE SOME PATCHY LIGHT RAIN AT TIMES. ALTHOUGH DRY MID AND
UPPER LEVELS WILL LIKELY KEEP MUCH OF THE AREA DRY FOR A MAJORITY
OF THE PERIOD. COMBINATION OF FRONT IN THE REGION AND LOW LEVEL
CLOUD COVER WILL TEMPER HIGHS ACROSS PORTIONS OF THE FORECAST AREA
BOTH DAYS. COASTAL SC ENDS UP WARMEST WITH A LITTLE LESS CLOUD
COVER AND SOUTHERLY FLOW INTO WED NIGHT. HIGHS WILL BE IN THE LOW
70S WITH LOWS IN THE UPPER 50S TO AROUND 60.
INLAND SC AND NC WILL HAVE BEST PRECIP CHANCES...THOUGH AT THIS
POINT LITTLE MORE THAN LOW CHANCE OR SLIGHT CHANCE APPEARS
WARRANTED. HIGH TEMP FORECAST WILL BE TRICKY IN THESE AREAS WITH
LOCATION OF FRONT...AND THE NORTHERLY FLOW BEHIND IT...LEADING TO A
SHARP GRADIENT SOMEWHERE IN THE FORECAST AREA. FOR NOW WILL GO WITH
HIGHS NEAR TO ABOVE CLIMO TUE AND ABOVE TO WELL ABOVE CLIMO WED.
HOWEVER A MORE EASTERLY POSITION OF THE FRONT WED...SOMETHING
GUIDANCE IS TRENDING AWAY FROM...WOULD RESULT IN COOLER TEMPS. LOWS
WILL CONTINUE TO RUN ABOVE CLIMO REGARDLESS OF FRONTAL POSITION
GIVEN PLENTY OF CLOUD COVER AND LIMITED COLD ADVECTION ON BACKSIDE
OF THE BOUNDARY.
FRONT IS PULLED OFF THE COAST WED NIGHT BY WEAK SURFACE LOW MOVING
INTO THE CANADIAN MARITIMES. LACK OF ANY MID LEVEL PUSH TRANSLATES
TO MINIMAL TEMP REDUCTION AS THE PERIOD ENDS. NORTH TO NORTHEAST
FLOW ACROSS THE AREA BY END OF PERIOD ONLY DROPS WED NIGHT LOWS A
FEW DEGREES.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 245 AM MONDAY...SOUTHERN STREAM SYSTEM EMERGING FROM THE
SOUTHWEST MID WEEK WILL BRING THE PERIODS BEST AND ONLY PRECIP
CHANCE THU NIGHT INTO FRI. DEEP SOUTHWEST FLOW AHEAD OF THE WAVE
AS IT CROSSES THE GULF COAST INCREASES MOISTURE OVER THE
SOUTHEAST THU. DIVERGENT PATTERN ALOFT THU NIGHT INTO FRI IS
ENHANCED BY 200MB JET STREAK APPROACHING 120 KT. RIGHT NOW THE
BIGGEST NEGATIVE FACTOR APPEARS TO BE THE TRACK OF THE MID LEVEL
FEATURE AND THE ASSOCIATED SURFACE WAVE. WEAK SURFACE LOW DEVELOPS
ALONG FRONT STALLED ACROSS NORTHERN GOMEX EARLY THU. THIS LOW
TRACKS NORTHEAST ALONG THE FRONT...PASSING OFF THE SOUTHEAST COAST.
THIS KEEPS NORTHEAST LOW LEVEL FLOW IN PLACE FOR THE DURATION OF
THE EVENT. BELOW 700MB OR SO FORECAST SOUNDINGS DEPICT A SATURATED
BUT VERY STABLE AIR MASS. SO WHILE MID AND UPPER LEVEL FORCING
WILL BE PRESENT IT APPEARS THE LOW LEVEL STABILITY WILL ULTIMATELY
WIN OUT. THUS HAVE GONE FOR LOWER POP AND MINIMAL QPF EARLY IN THE
PERIOD.
AS SURFACE AND MID LEVEL FEATURES MOVE OFF TO THE NORTHEAST HIGH
PRESSURE BUILDS IN UNDER DEVELOPING PROGRESSIVE MID LEVEL PATTERN.
THIS ALLOWS MUCH DRIER AND COOLER AIR TO SPREAD IN FROM THE WEST.
PINCHED GRADIENT ALONG THE COAST WILL KEEP NORTHEAST FLOW BRISK INTO
SAT MORNING...ESPECIALLY ALONG THE COAST. LATE IN THE PERIOD MEDIUM
RANGE GUIDANCE IS TRYING TO SHOW A WEAK COASTAL LOW DEVELOPING ON
REMAINS OF STALLED SURFACE BOUNDARY. GIVEN THE TIME RANGE AND
POTENTIAL FOR SIGNIFICANT CHANGES REGARDING THIS FEATURE WILL NOT
INTRODUCE A POP LATE IN THE PERIOD. TEMPS NEAR CLIMO THROUGH THE
PERIOD.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 18Z...STAGNANT SYNOPTIC PATTERN WILL KEEP THE FRONT WEST OF
THE REGION...WITH MAINLY THICK HIGH CLOUDS IN AND OUT OF OUR WESTERN
TERMINALS. SOUTHWEST FLOW THIS AFTERNOON WILL SHIFT 20-30 DEGREES TO
THE SOUTH WITH THE RESULTANT AROUND BEGINNING OF TAF TIME.
TONIGHT...FRONT REMAINS WEST OF THE REGION...IT MAY IN FACT
RETROGRADE FARTHER WEST. SCATTERED CIRRUS OVERNIGHT WITH A GOOD
CHANCE OF FOG/STRATUS AFTER 08Z. TUESDAY...BECOMING VFR BY 14-15Z
WITH CONTINUED SOUTHWEST FLOW.
EXTENDED OUTLOOK...MORNING FOG/STRATUS EXPECTED AT ALL TERMINALS
WEDNESDAY. SLIGHT CHANCE OF SHOWERS WEDNESDAY AFTERNOON. A BETTER
CHANCE OF SHOWERS FRIDAY INTO SATURDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM MONDAY...SFC PRESSURE PATTERN INDICATES THE WESTERN
ATLANTIC HIGH...CENTERED OFFSHORE FROM THE SE U.S. COAST...WILL
PRODUCE SSW THROUGH WSW WIND DIRECTIONS. THE SFC PG WILL SLIGHTLY
TIGHTEN AS THE SFC COLD FRONT APPROACHES FROM THE NW TODAY...
BEFORE STALLING BETWEEN DUCK NC SOUTHWEST TO PENSACOLA BEACH
FLORIDA TONIGHT. LOOK FOR WIND SPEEDS AT 5 TO 10 KT THIS
MORNING...INCREASING TO 10 TO POSSIBLY 15 KT THIS AFTERNOON AND
TONIGHT. SIGNIFICANT SEAS WILL RUN 2 TO 3 FT...EXCEPT UP TO 4 FT
ACROSS THE OUTER WATERS OFF CAPE FEAR THIS AFTERNOON AND/OR
TONIGHT. GENERALLY...A 1 1/2 TO 2 1/2 FOOT ESE GROUND SWELL
EXHIBITING 9 TO 12 SECOND PERIODS WILL DOMINATE SIG. SEAS. THE
ADDITION OF 3 TO 5 SECOND PERIOD WIND DRIVEN WAVES WILL PUSH SIG.
SEAS TO THE 4 FOOT LEVEL OFF CAPE FEAR LATER TODAY AND TONIGHT.
SEA FOG WILL ALSO REMAIN A THREAT TO MARINERS THIS FORECAST
PERIOD...OCCASIONALLY AND BRIEFLY MOVING ONSHORE. VSBY ROUGHLY 1
NM OR LESS WITHIN THE SEA FOG.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 245 AM MONDAY...SOUTHWEST FLOW REMAINS IN PLACE FOR A
MAJORITY OF THE PERIOD WITH SPEEDS GENERALLY 10 TO 15 KT. WEAK
SLOW MOVING FRONT DROPPING IN FROM THE NORTH-NORTHWEST LATE IN THE
PERIOD WILL BRING ABOUT A WIND SHIFT TO NORTHERLY BY THE END OF
THE PERIOD BUT LACK OF COLD ADVECTION OR SIGNIFICANT GRADIENT WILL
KEEP SPEEDS LIGHT...10 KT OR LESS. SEAS WILL RUN 2 TO 4 FT THROUGH
THE PERIOD...MAINLY AS SOUTHERLY WIND WAVE.
LONG TERM /THURSDAY THROUGH FRIDAY/...
AS OF 245 AM MONDAY...NORTH TO NORTHEAST FLOW THU STARTS TO
INCREASE THU NIGHT...BUT QUESTION REMAINS BY HOW MUCH. WEAK LOW
PRESSURE EMERGING FROM NORTHEAST GOMEX WILL PINCH GRADIENT...BUT
HOW TIGHT GRADIENT BETWEEN THIS LOW AND THE HIGH BUILDING IN FROM
THE NORTHWEST BECOMES IS UNCERTAIN. ALL OF THE MEDIUM RANGE
GUIDANCE DEPICTS THIS SURFACE WAVE PASSING EAST OF THE WATERS
LATE THU NIGHT OR EARLY FRI...SO FEEL THAT AN INCREASE IN
NORTHEAST FLOW IS LIKELY FOR SECOND HALF OF THE PERIOD. AT THIS
POINT CANNOT SAY IF HEADLINES WILL BE NEEDED BUT IT CERTAINLY
APPEARS TO BE A POSSIBILITY. CURRENT SEAS FORECAST IS 2 TO 4 FT
THU BUILDING TO 3 TO 5 ON FRI. HOWEVER IT IS WORTH NOTING THAT WW3
GUIDANCE IS COMING IN CLOSE TO 10 FT FRI.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...III
LONG TERM...III
AVIATION...DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1036 AM EST MON JAN 14 2013
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PRODUCE UNSEASONABLY WARM CONDITIONS
INTO MID-WEEK. A COLD FRONT WILL MOVE SLOWLY THROUGH THE AREA
LATE WEDNESDAY. WEAK GULF COAST LOW PRESSURE MAY BRING A CHANCE OF
LIGHT RAIN TO THE REGION THURSDAY NIGHT OR FRIDAY. HIGH PRESSURE
WILL BUILD IN BEHIND THE COLD FRONT FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM MONDAY...HAVE ADJUSTED TEMPS UP A COUPLE OF DEGREES
FOR TODAY KEEPING MAX TEMPS IN THE MID TO UPPER 70S. THE
SOUTHWESTERLY WINDS WILL BACK A BIT PRODUCING MORE OF AN ON
SHORE FLOW THROUGH THE AFTERNOON. THIS WILL KEEP TEMPS COOLER
ALONG THE SHORE...MOVING INLAND AS WINDS PICK UP THROUGH THE
AFTERNOON. SEA FOG WILL ALSO HELP TO KEEP TEMPS COOLER ALONG THE
COAST.
PREVIOUS DISCUSSION...MODELS INDICATE THE MID TO UPPER LEVEL RIDGE TO
REMAIN ANCHORED JUST OFF THE SE U.S. COAST DURING THIS NEAR TERM
PERIOD. THIS WILL SLOW DOWN THE PROGRESSION OF THE BAROCLINIC ZONE
IE. THE SFC COLD FRONT...TOWARD THE SOUTHEAST. IN FACT... MODELS
ACTUALLY STALL THE COLD FRONT JUST NORTH AND WEST OF THE FA AS IT
BECOMES ORIENTED PARALLEL WITH THE FLOW ALOFT. THE DEEPEST
MOISTURE WILL REMAIN JUST OUTSIDE OF THE ILM CWA DURING THIS NEAR
TERM PERIOD...REMAINING WEST THROUGH NORTH OF THE FA. AMAZINGLY...
GFS/NAM/EUROPEAN/ETC. AGREE THAT THIS SCENARIO WILL PLAY OUT. NOW
WHAT THEY DO NOT AGREE IS THE THREAT OR PROBABILITY FOR PCPN. WITH
THE BEST LIFT REMAINING OUTSIDE OF THE ILM CWA DOMAIN...HAVE
INDICATED A LOW CHANCE OF POPS FOR THE NW PORTIONS OF THE FA FROM
THIS AFTERNOON THROUGH TONIGHT...ROUGHLY ALONG AND WEST OF THE
I-95 CORRIDOR. THE LATEST RUN OF THE HRRR MODEL ALSO INDICATES
THIS PCPN POSSIBILITY. HAVE STAYED AWAY FROM MENTIONING THUNDER
DUE TO THE LACK OF INSTABILITY ILLUSTRATED BY LATEST NAMBUFR
SOUNDINGS...IE. NO CAPE...LI`S STAY MAINLY POSITIVE. WILL LIKELY
HAVE A SOMEWHAT OF A SHARP CLOUD GRADIENT ACROSS THE FA WITH THE
IMMEDIATE COAST HAVING THE BEST POTENTIAL TO OBSERVE THE DAYS
INSOLATION. THEREFORE...HAVE RELIED ON THE WARMER MODEL MOS
GUIDANCE FOR BOTH TODAYS MAX AND TONIGHTS MIN TEMPS. THIS WILL
RESULT IN ADDITIONAL MAX TEMP RECORDS LIKELY BEING SET FOR 1 MORE
DAY. AND FINALLY...THE MID TO UPPER LEVEL CLOUD DECK ACROSS THE FA
HAS BEEN OPAQUE ENOUGH TO PREVENT WIDESPREAD RADIATIONAL TYPE
DENSE FOG. HOWEVER...SEA FOG IE. ADVECTION TYPE FOG...WILL
SPORADICALLY AFFECT THE IMMEDIATE COAST AS SFC WINDS SLIGHTLY BACK
TO THE SSW AND PUSH 60+ DEWPOINTS ACROSS SSTS IN THE 50S RESULTING
WITH SEA FOG BRIEFLY PUSHING ONSHORE AT TIMES.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 245 AM MONDAY...WEAK FRONT WILL BE STALLED IN OR JUST WEST
OF THE REGION FOR A MAJORITY OF THE PERIOD. PROXIMITY TO FRONT
WILL CREATE SIGNIFICANT TEMP GRADIENT ACROSS THE
REGION...PROVIDING PLENTY OF POTENTIAL FOR THE FORECAST TO GO
WRONG. SOME WEAK ISENTROPIC LIFT AND LOW LEVEL MOISTURE MAY
PRODUCE SOME PATCHY LIGHT RAIN AT TIMES. ALTHOUGH DRY MID AND
UPPER LEVELS WILL LIKELY KEEP MUCH OF THE AREA DRY FOR A MAJORITY
OF THE PERIOD. COMBINATION OF FRONT IN THE REGION AND LOW LEVEL
CLOUD COVER WILL TEMPER HIGHS ACROSS PORTIONS OF THE FORECAST AREA
BOTH DAYS. COASTAL SC ENDS UP WARMEST WITH A LITTLE LESS CLOUD
COVER AND SOUTHERLY FLOW INTO WED NIGHT. HIGHS WILL BE IN THE LOW
70S WITH LOWS IN THE UPPER 50S TO AROUND 60.
INLAND SC AND NC WILL HAVE BEST PRECIP CHANCES...THOUGH AT THIS
POINT LITTLE MORE THAN LOW CHANCE OR SLIGHT CHANCE APPEARS
WARRANTED. HIGH TEMP FORECAST WILL BE TRICKY IN THESE AREAS WITH
LOCATION OF FRONT...AND THE NORTHERLY FLOW BEHIND IT...LEADING TO A
SHARP GRADIENT SOMEWHERE IN THE FORECAST AREA. FOR NOW WILL GO WITH
HIGHS NEAR TO ABOVE CLIMO TUE AND ABOVE TO WELL ABOVE CLIMO WED.
HOWEVER A MORE EASTERLY POSITION OF THE FRONT WED...SOMETHING
GUIDANCE IS TRENDING AWAY FROM...WOULD RESULT IN COOLER TEMPS. LOWS
WILL CONTINUE TO RUN ABOVE CLIMO REGARDLESS OF FRONTAL POSITION
GIVEN PLENTY OF CLOUD COVER AND LIMITED COLD ADVECTION ON BACKSIDE
OF THE BOUNDARY.
FRONT IS PULLED OFF THE COAST WED NIGHT BY WEAK SURFACE LOW MOVING
INTO THE CANADIAN MARITIMES. LACK OF ANY MID LEVEL PUSH TRANSLATES
TO MINIMAL TEMP REDUCTION AS THE PERIOD ENDS. NORTH TO NORTHEAST
FLOW ACROSS THE AREA BY END OF PERIOD ONLY DROPS WED NIGHT LOWS A
FEW DEGREES.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 245 AM MONDAY...SOUTHERN STREAM SYSTEM EMERGING FROM THE
SOUTHWEST MID WEEK WILL BRING THE PERIODS BEST AND ONLY PRECIP
CHANCE THU NIGHT INTO FRI. DEEP SOUTHWEST FLOW AHEAD OF THE WAVE
AS IT CROSSES THE GULF COAST INCREASES MOISTURE OVER THE
SOUTHEAST THU. DIVERGENT PATTERN ALOFT THU NIGHT INTO FRI IS
ENHANCED BY 200MB JET STREAK APPROACHING 120 KT. RIGHT NOW THE
BIGGEST NEGATIVE FACTOR APPEARS TO BE THE TRACK OF THE MID LEVEL
FEATURE AND THE ASSOCIATED SURFACE WAVE. WEAK SURFACE LOW DEVELOPS
ALONG FRONT STALLED ACROSS NORTHERN GOMEX EARLY THU. THIS LOW
TRACKS NORTHEAST ALONG THE FRONT...PASSING OFF THE SOUTHEAST COAST.
THIS KEEPS NORTHEAST LOW LEVEL FLOW IN PLACE FOR THE DURATION OF
THE EVENT. BELOW 700MB OR SO FORECAST SOUNDINGS DEPICT A SATURATED
BUT VERY STABLE AIR MASS. SO WHILE MID AND UPPER LEVEL FORCING
WILL BE PRESENT IT APPEARS THE LOW LEVEL STABILITY WILL ULTIMATELY
WIN OUT. THUS HAVE GONE FOR LOWER POP AND MINIMAL QPF EARLY IN THE
PERIOD.
AS SURFACE AND MID LEVEL FEATURES MOVE OFF TO THE NORTHEAST HIGH
PRESSURE BUILDS IN UNDER DEVELOPING PROGRESSIVE MID LEVEL PATTERN.
THIS ALLOWS MUCH DRIER AND COOLER AIR TO SPREAD IN FROM THE WEST.
PINCHED GRADIENT ALONG THE COAST WILL KEEP NORTHEAST FLOW BRISK INTO
SAT MORNING...ESPECIALLY ALONG THE COAST. LATE IN THE PERIOD MEDIUM
RANGE GUIDANCE IS TRYING TO SHOW A WEAK COASTAL LOW DEVELOPING ON
REMAINS OF STALLED SURFACE BOUNDARY. GIVEN THE TIME RANGE AND
POTENTIAL FOR SIGNIFICANT CHANGES REGARDING THIS FEATURE WILL NOT
INTRODUCE A POP LATE IN THE PERIOD. TEMPS NEAR CLIMO THROUGH THE
PERIOD.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AS OF 12Z...LBT IS LIFR AND WILL LIKELY NOT REACH VFR UNTIL
14Z...PERHAPS EVEN AN HOUR LATER. THE OTHER TERMINALS APPEAR TO HAVE
ENOUGH SOUTHWEST FLOW TO MIX OUT A BIT EARLIER. STAGNANT SYNOPTIC
PATTERN WILL KEEP THE FRONT WEST OF THE REGION...WITH MAINLY THICK
HIGH CLOUDS IN AND OUT OF OUR WESTERN TERMINALS. ALONG THE
COAST...GOOD LOW LEVEL MOISTURE WILL GIVE US A CHANCE OF AN MVFR
CEILING IN AND OUT THROUGH EARLY AFTERNOON. SOUTHWEST FLOW WILL
CONTINUE THROUGH THE OVERNIGHT HOURS. IT APPEARS THE WINDS WILL BE
TOO STRONG TO SUPPORT FOG...BUT WILL REEVALUATE ON THE NEXT SET OF
TAFS.
EXTENDED OUTLOOK...POSSIBLE RESTRICTIONS IN ASSOCIATION WITH COLD
FRONT TUESDAY AND WEDNESDAY...MAINLY AT THE INLAND TERMINALS.
CHANCE FOR SHOWERS THURSDAY. OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM MONDAY...SFC PRESSURE PATTERN INDICATES THE WESTERN
ATLANTIC HIGH...CENTERED OFFSHORE FROM THE SE U.S. COAST...WILL
PRODUCE SSW THROUGH WSW WIND DIRECTIONS. THE SFC PG WILL SLIGHTLY
TIGHTEN AS THE SFC COLD FRONT APPROACHES FROM THE NW TODAY...
BEFORE STALLING BETWEEN DUCK NC SOUTHWEST TO PENSACOLA BEACH
FLORIDA TONIGHT. LOOK FOR WIND SPEEDS AT 5 TO 10 KT THIS
MORNING...INCREASING TO 10 TO POSSIBLY 15 KT THIS AFTERNOON AND
TONIGHT. SIGNIFICANT SEAS WILL RUN 2 TO 3 FT...EXCEPT UP TO 4 FT
ACROSS THE OUTER WATERS OFF CAPE FEAR THIS AFTERNOON AND/OR
TONIGHT. GENERALLY...A 1 1/2 TO 2 1/2 FOOT ESE GROUND SWELL
EXHIBITING 9 TO 12 SECOND PERIODS WILL DOMINATE SIG. SEAS. THE
ADDITION OF 3 TO 5 SECOND PERIOD WIND DRIVEN WAVES WILL PUSH SIG.
SEAS TO THE 4 FOOT LEVEL OFF CAPE FEAR LATER TODAY AND TONIGHT.
SEA FOG WILL ALSO REMAIN A THREAT TO MARINERS THIS FORECAST
PERIOD...OCCASIONALLY AND BRIEFLY MOVING ONSHORE. VSBY ROUGHLY 1
NM OR LESS WITHIN THE SEA FOG.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 245 AM MONDAY...SOUTHWEST FLOW REMAINS IN PLACE FOR A
MAJORITY OF THE PERIOD WITH SPEEDS GENERALLY 10 TO 15 KT. WEAK
SLOW MOVING FRONT DROPPING IN FROM THE NORTH-NORTHWEST LATE IN THE
PERIOD WILL BRING ABOUT A WIND SHIFT TO NORTHERLY BY THE END OF
THE PERIOD BUT LACK OF COLD ADVECTION OR SIGNIFICANT GRADIENT WILL
KEEP SPEEDS LIGHT...10 KT OR LESS. SEAS WILL RUN 2 TO 4 FT THROUGH
THE PERIOD...MAINLY AS SOUTHERLY WIND WAVE.
LONG TERM /THURSDAY THROUGH FRIDAY/...
AS OF 245 AM MONDAY...NORTH TO NORTHEAST FLOW THU STARTS TO
INCREASE THU NIGHT...BUT QUESTION REMAINS BY HOW MUCH. WEAK LOW
PRESSURE EMERGING FROM NORTHEAST GOMEX WILL PINCH GRADIENT...BUT
HOW TIGHT GRADIENT BETWEEN THIS LOW AND THE HIGH BUILDING IN FROM
THE NORTHWEST BECOMES IS UNCERTAIN. ALL OF THE MEDIUM RANGE
GUIDANCE DEPICTS THIS SURFACE WAVE PASSING EAST OF THE WATERS
LATE THU NIGHT OR EARLY FRI...SO FEEL THAT AN INCREASE IN
NORTHEAST FLOW IS LIKELY FOR SECOND HALF OF THE PERIOD. AT THIS
POINT CANNOT SAY IF HEADLINES WILL BE NEEDED BUT IT CERTAINLY
APPEARS TO BE A POSSIBILITY. CURRENT SEAS FORECAST IS 2 TO 4 FT
THU BUILDING TO 3 TO 5 ON FRI. HOWEVER IT IS WORTH NOTING THAT WW3
GUIDANCE IS COMING IN CLOSE TO 10 FT FRI.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...RGZ
SHORT TERM...III
LONG TERM...III
AVIATION...DL
MARINE...
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
641 AM EST MON JAN 14 2013
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PRODUCE UNSEASONABLY WARM CONDITIONS
INTO MID-WEEK. A COLD FRONT WILL MOVE SLOWLY THROUGH THE AREA
LATE WEDNESDAY. WEAK GULF COAST LOW PRESSURE MAY BRING A CHANCE OF
LIGHT RAIN TO THE REGION THURSDAY NIGHT OR FRIDAY. HIGH PRESSURE
WILL BUILD IN BEHIND THE COLD FRONT FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM MONDAY...MODELS INDICATE THE MID TO UPPER LEVEL RIDGE
TO REMAIN ANCHORED JUST OFF THE SE U.S. COAST DURING THIS NEAR
TERM PERIOD. THIS WILL SLOW DOWN THE PROGRESSION OF THE BAROCLINIC
ZONE IE. THE SFC COLD FRONT...TOWARD THE SOUTHEAST. IN FACT...
MODELS ACTUALLY STALL THE COLD FRONT JUST NORTH AND WEST OF THE FA
AS IT BECOMES ORIENTED PARALLEL WITH THE FLOW ALOFT. THE DEEPEST
MOISTURE WILL REMAIN JUST OUTSIDE OF THE ILM CWA DURING THIS NEAR
TERM PERIOD...REMAINING WEST THROUGH NORTH OF THE FA. AMAZINGLY...
GFS/NAM/EUROPEAN/ETC. AGREE THAT THIS SCENARIO WILL PLAY OUT. NOW
WHAT THEY DO NOT AGREE IS THE THREAT OR PROBABILITY FOR PCPN. WITH
THE BEST LIFT REMAINING OUTSIDE OF THE ILM CWA DOMAIN...HAVE
INDICATED A LOW CHANCE OF POPS FOR THE NW PORTIONS OF THE FA FROM
THIS AFTERNOON THROUGH TONIGHT...ROUGHLY ALONG AND WEST OF THE
I-95 CORRIDOR. THE LATEST RUN OF THE HRRR MODEL ALSO INDICATES
THIS PCPN POSSIBILITY. HAVE STAYED AWAY FROM MENTIONING THUNDER
DUE TO THE LACK OF INSTABILITY ILLUSTRATED BY LATEST NAMBUFR
SOUNDINGS...IE. NO CAPE...LI`S STAY MAINLY POSITIVE. WILL LIKELY
HAVE A SOMEWHAT OF A SHARP CLOUD GRADIENT ACROSS THE FA WITH THE
IMMEDIATE COAST HAVING THE BEST POTENTIAL TO OBSERVE THE DAYS
INSOLATION. THEREFORE...HAVE RELIED ON THE WARMER MODEL MOS
GUIDANCE FOR BOTH TODAYS MAX AND TONIGHTS MIN TEMPS. THIS WILL
RESULT IN ADDITIONAL MAX TEMP RECORDS LIKELY BEING SET FOR 1 MORE
DAY. AND FINALLY...THE MID TO UPPER LEVEL CLOUD DECK ACROSS THE FA
HAS BEEN OPAQUE ENOUGH TO PREVENT WIDESPREAD RADIATIONAL TYPE
DENSE FOG. HOWEVER...SEA FOG IE. ADVECTION TYPE FOG...WILL
SPORADICALLY AFFECT THE IMMEDIATE COAST AS SFC WINDS SLIGHTLY BACK
TO THE SSW AND PUSH 60+ DEWPOINTS ACROSS SSTS IN THE 50S RESULTING
WITH SEA FOG BRIEFLY PUSHING ONSHORE AT TIMES.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 245 AM MONDAY...WEAK FRONT WILL BE STALLED IN OR JUST WEST
OF THE REGION FOR A MAJORITY OF THE PERIOD. PROXIMITY TO FRONT
WILL CREATE SIGNIFICANT TEMP GRADIENT ACROSS THE
REGION...PROVIDING PLENTY OF POTENTIAL FOR THE FORECAST TO GO
WRONG. SOME WEAK ISENTROPIC LIFT AND LOW LEVEL MOISTURE MAY
PRODUCE SOME PATCHY LIGHT RAIN AT TIMES. ALTHOUGH DRY MID AND
UPPER LEVELS WILL LIKELY KEEP MUCH OF THE AREA DRY FOR A MAJORITY
OF THE PERIOD. COMBINATION OF FRONT IN THE REGION AND LOW LEVEL
CLOUD COVER WILL TEMPER HIGHS ACROSS PORTIONS OF THE FORECAST AREA
BOTH DAYS. COASTAL SC ENDS UP WARMEST WITH A LITTLE LESS CLOUD
COVER AND SOUTHERLY FLOW INTO WED NIGHT. HIGHS WILL BE IN THE LOW
70S WITH LOWS IN THE UPPER 50S TO AROUND 60.
INLAND SC AND NC WILL HAVE BEST PRECIP CHANCES...THOUGH AT THIS
POINT LITTLE MORE THAN LOW CHANCE OR SLIGHT CHANCE APPEARS
WARRANTED. HIGH TEMP FORECAST WILL BE TRICKY IN THESE AREAS WITH
LOCATION OF FRONT...AND THE NORTHERLY FLOW BEHIND IT...LEADING TO A
SHARP GRADIENT SOMEWHERE IN THE FORECAST AREA. FOR NOW WILL GO WITH
HIGHS NEAR TO ABOVE CLIMO TUE AND ABOVE TO WELL ABOVE CLIMO WED.
HOWEVER A MORE EASTERLY POSITION OF THE FRONT WED...SOMETHING
GUIDANCE IS TRENDING AWAY FROM...WOULD RESULT IN COOLER TEMPS. LOWS
WILL CONTINUE TO RUN ABOVE CLIMO REGARDLESS OF FRONTAL POSITION
GIVEN PLENTY OF CLOUD COVER AND LIMITED COLD ADVECTION ON BACKSIDE
OF THE BOUNDARY.
FRONT IS PULLED OFF THE COAST WED NIGHT BY WEAK SURFACE LOW MOVING
INTO THE CANADIAN MARITIMES. LACK OF ANY MID LEVEL PUSH TRANSLATES
TO MINIMAL TEMP REDUCTION AS THE PERIOD ENDS. NORTH TO NORTHEAST
FLOW ACROSS THE AREA BY END OF PERIOD ONLY DROPS WED NIGHT LOWS A
FEW DEGREES.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 245 AM MONDAY...SOUTHERN STREAM SYSTEM EMERGING FROM THE
SOUTHWEST MID WEEK WILL BRING THE PERIODS BEST AND ONLY PRECIP
CHANCE THU NIGHT INTO FRI. DEEP SOUTHWEST FLOW AHEAD OF THE WAVE
AS IT CROSSES THE GULF COAST INCREASES MOISTURE OVER THE
SOUTHEAST THU. DIVERGENT PATTERN ALOFT THU NIGHT INTO FRI IS
ENHANCED BY 200MB JET STREAK APPROACHING 120 KT. RIGHT NOW THE
BIGGEST NEGATIVE FACTOR APPEARS TO BE THE TRACK OF THE MID LEVEL
FEATURE AND THE ASSOCIATED SURFACE WAVE. WEAK SURFACE LOW DEVELOPS
ALONG FRONT STALLED ACROSS NORTHERN GOMEX EARLY THU. THIS LOW
TRACKS NORTHEAST ALONG THE FRONT...PASSING OFF THE SOUTHEAST COAST.
THIS KEEPS NORTHEAST LOW LEVEL FLOW IN PLACE FOR THE DURATION OF
THE EVENT. BELOW 700MB OR SO FORECAST SOUNDINGS DEPICT A SATURATED
BUT VERY STABLE AIR MASS. SO WHILE MID AND UPPER LEVEL FORCING
WILL BE PRESENT IT APPEARS THE LOW LEVEL STABILITY WILL ULTIMATELY
WIN OUT. THUS HAVE GONE FOR LOWER POP AND MINIMAL QPF EARLY IN THE
PERIOD.
AS SURFACE AND MID LEVEL FEATURES MOVE OFF TO THE NORTHEAST HIGH
PRESSURE BUILDS IN UNDER DEVELOPING PROGRESSIVE MID LEVEL PATTERN.
THIS ALLOWS MUCH DRIER AND COOLER AIR TO SPREAD IN FROM THE WEST.
PINCHED GRADIENT ALONG THE COAST WILL KEEP NORTHEAST FLOW BRISK INTO
SAT MORNING...ESPECIALLY ALONG THE COAST. LATE IN THE PERIOD MEDIUM
RANGE GUIDANCE IS TRYING TO SHOW A WEAK COASTAL LOW DEVELOPING ON
REMAINS OF STALLED SURFACE BOUNDARY. GIVEN THE TIME RANGE AND
POTENTIAL FOR SIGNIFICANT CHANGES REGARDING THIS FEATURE WILL NOT
INTRODUCE A POP LATE IN THE PERIOD. TEMPS NEAR CLIMO THROUGH THE
PERIOD.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AS OF 12Z...LBT IS LIFR AND WILL LIKELY NOT REACH VFR UNTIL
14Z...PERHAPS EVEN AN HOUR LATER. THE OTHER TERMINALS APPEAR TO HAVE
ENOUGH SOUTHWEST FLOW TO MIX OUT A BIT EARLIER. STAGNANT SYNOPTIC
PATTERN WILL KEEP THE FRONT WEST OF THE REGION...WITH MAINLY THICK
HIGH CLOUDS IN AND OUT OF OUR WESTERN TERMINALS. ALONG THE
COAST...GOOD LOW LEVEL MOISTURE WILL GIVE US A CHANCE OF AN MVFR
CEILING IN AND OUT THROUGH EARLY AFTERNOON. SOUTHWEST FLOW WILL
CONTINUE THROUGH THE OVERNIGHT HOURS. IT APPEARS THE WINDS WILL BE
TOO STRONG TO SUPPORT FOG...BUT WILL REEVALUATE ON THE NEXT SET OF
TAFS.
EXTENDED OUTLOOK...POSSIBLE RESTRICTIONS IN ASSOCIATION WITH COLD
FRONT TUESDAY AND WEDNESDAY...MAINLY AT THE INLAND TERMINALS.
CHANCE FOR SHOWERS THURSDAY. OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 330 AM MONDAY...SFC PRESSURE PATTERN INDICATES THE WESTERN
ATLANTIC HIGH...CENTERED OFFSHORE FROM THE SE U.S. COAST...WILL
PRODUCE SSW THROUGH WSW WIND DIRECTIONS. THE SFC PG WILL SLIGHTLY
TIGHTEN AS THE SFC COLD FRONT APPROACHES FROM THE NW TODAY...
BEFORE STALLING BETWEEN DUCK NC SOUTHWEST TO PENSACOLA BEACH
FLORIDA TONIGHT. LOOK FOR WIND SPEEDS AT 5 TO 10 KT THIS
MORNING...INCREASING TO 10 TO POSSIBLY 15 KT THIS AFTERNOON AND
TONIGHT. SIGNIFICANT SEAS WILL RUN 2 TO 3 FT...EXCEPT UP TO 4 FT
ACROSS THE OUTER WATERS OFF CAPE FEAR THIS AFTERNOON AND/OR
TONIGHT. GENERALLY...A 1 1/2 TO 2 1/2 FOOT ESE GROUND SWELL
EXHIBITING 9 TO 12 SECOND PERIODS WILL DOMINATE SIG. SEAS. THE
ADDITION OF 3 TO 5 SECOND PERIOD WIND DRIVEN WAVES WILL PUSH SIG.
SEAS TO THE 4 FOOT LEVEL OFF CAPE FEAR LATER TODAY AND TONIGHT.
SEA FOG WILL ALSO REMAIN A THREAT TO MARINERS THIS FORECAST
PERIOD...OCCASIONALLY AND BRIEFLY MOVING ONSHORE. VSBY ROUGHLY 1
NM OR LESS WITHIN THE SEA FOG.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 245 AM MONDAY...SOUTHWEST FLOW REMAINS IN PLACE FOR A
MAJORITY OF THE PERIOD WITH SPEEDS GENERALLY 10 TO 15 KT. WEAK
SLOW MOVING FRONT DROPPING IN FROM THE NORTH-NORTHWEST LATE IN THE
PERIOD WILL BRING ABOUT A WIND SHIFT TO NORTHERLY BY THE END OF
THE PERIOD BUT LACK OF COLD ADVECTION OR SIGNIFICANT GRADIENT WILL
KEEP SPEEDS LIGHT...10 KT OR LESS. SEAS WILL RUN 2 TO 4 FT THROUGH
THE PERIOD...MAINLY AS SOUTHERLY WIND WAVE.
LONG TERM /THURSDAY THROUGH FRIDAY/...
AS OF 245 AM MONDAY...NORTH TO NORTHEAST FLOW THU STARTS TO
INCREASE THU NIGHT...BUT QUESTION REMAINS BY HOW MUCH. WEAK LOW
PRESSURE EMERGING FROM NORTHEAST GOMEX WILL PINCH GRADIENT...BUT
HOW TIGHT GRADIENT BETWEEN THIS LOW AND THE HIGH BUILDING IN FROM
THE NORTHWEST BECOMES IS UNCERTAIN. ALL OF THE MEDIUM RANGE
GUIDANCE DEPICTS THIS SURFACE WAVE PASSING EAST OF THE WATERS
LATE THU NIGHT OR EARLY FRI...SO FEEL THAT AN INCREASE IN
NORTHEAST FLOW IS LIKELY FOR SECOND HALF OF THE PERIOD. AT THIS
POINT CANNOT SAY IF HEADLINES WILL BE NEEDED BUT IT CERTAINLY
APPEARS TO BE A POSSIBILITY. CURRENT SEAS FORECAST IS 2 TO 4 FT
THU BUILDING TO 3 TO 5 ON FRI. HOWEVER IT IS WORTH NOTING THAT WW3
GUIDANCE IS COMING IN CLOSE TO 10 FT FRI.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...III
NEAR TERM...DCH
SHORT TERM...III
LONG TERM...III
AVIATION...DCH/SGL
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
636 AM EST MON JAN 14 2013
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION THROUGH THE FIRST PART OF
THE WORK WEEK. THIS WILL LEAD TO MAINLY DRY CONDITIONS AND MORE
SEASONABLE TEMPERATURES THROUGH WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE WILL BUILD INTO THE REGION THROUGH THIS AFTERNOON.
AS IT DOES...NORTH TO NORTHWEST LOW LEVEL FLOW WILL DECREASE BUT
WEAK CAA WILL CONTINUE THROUGH MUCH OF THE DAY. A FAIR AMOUNT OF
LOW CLOUDS ARE STILL IN PLACE ACROSS THE REGION BUT SATELLITE
IMAGES ARE INDICATING SOME BREAKS ACROSS PARTS OF OUR SOUTHWEST.
MAIN QUESTION FOR TODAY WILL BE HOW FAST THESE CLOUDS DISSIPATE.
THE RAP IS HANGING ON TO A FAIR AMOUNT OF LOW LEVEL MOISTURE
THROUGH THIS AFTERNOON. THIS IS PROBABLY OVERDONE AND PREFER
SOMETHING CLOSER TO WHAT THE NAM IS INDICATING ALTHOUGH THE WEAK
CAA MAY HELP KEEP THE CLOUDS AROUND A BIT LONGER. WILL THEREFORE
ALLOW FOR PARTIAL CLEARING HEADING THROUGH LATE MORNING INTO EARLY
AFTERNOON. 500 MB MOISTURE WILL INCREASE FROM THE SOUTHWEST LATER
THIS AFTERNOON AND THIS COULD ALLOW FOR AN INCREASE IN SOME
HIGHER LEVEL CLOUDS LATER TODAY. WITH WEAK CAA...EXPECT HIGHS
RANGING FROM THE UPPER 20S TO LOWER 30S IN THE NORTHWEST TO THE
MID AND UPPER 30S ACROSS THE SOUTHEAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
SURFACE HIGH PRESSURE WILL REMAIN ACROSS THE AREA TUESDAY INTO
WEDNESDAY...PROVIDING MAINLY DRY CONDITIONS. THE ONE EXCEPTION
COULD BE ACROSS OUR FAR SOUTHEAST AS A COUPLE OF SHORT WAVES RIDE
UP ALONG THE APPALACHIANS. THE MODELS HAVE TRENDED A BIT FARTHER
NORTH WITH THEIR NORTHERN PERIPHERY WITH THE INITIAL WAVE TONIGHT
AND THEN THE SECOND ONE FOR TUESDAY NIGHT. BOTH THE 00Z ECMWF AND
GFS ARE TRYING TO BRUSH A FEW OF OUR SOUTHEASTERN COUNTIES WITH
PCPN WHILE THE 00Z AND 06Z NAM ARE KEEPING EVERYTHING TO THE
SOUTH. GIVEN THE TRENDS...WILL GO AHEAD AND INTRODUCE SOME POPS
ACROSS THE FAR SOUTHEAST FOR TONIGHT AND TUESDAY NIGHT...BUT KEEP
THEM LOW AT THIS POINT. FORECAST SOUNDINGS ARE INDICATING THE
POSSIBILITY OF A RAIN/SNOW MIX WITH ANY PCPN BUT GIVEN THAT IT
WOULD BE AT NIGHT...IT MAY BE MORE LIKELY TO BE SNOW THAN RAIN.
CLOUDS WILL BE DEPENDENT ON JUST HOW FAR NORTH THESE WAVES MAKE IT
AND THIS WILL ALSO HAVE AN AFFECT ON LOW TEMPERATURES BOTH TONIGHT
AND TUESDAY NIGHT. WILL GO AHEAD AND ALLOW FOR A DECENT GRADIENT
BOTH NIGHTS FROM NORTHWEST TO SOUTHEAST ACROSS THE AREA.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE BUILDS BACK INTO THE OH AND TN VALLEYS THU INTO
FRI.
ENERGY KEEPS RUNNING THROUGH THE SUBTLE ERN U.S. LONGWAVE TROF OVER
THE WEEKEND. GFS AND ECMWF DIFFER ON THE STRENGTH OF A SYSTEM ON
SATURDAY....BUT BOTH PUSH COOLER AIR IN ON SUNDAY WITH A TRAILING
COLD FRONT. ONCE AGAIN THE MOISTURE IS LOOKING LIMITED FOR
SUNDAY...SO KEPT THE FCST DRY.
COOLER AIR BEHIND WEDNESDAYS SYSTEM WILL FILTER IN FOR
THU...DROPPING HIGHS INTO 30S. THE SEE-SAW TEMPERATURES WILL
CONTINUE...AS A WARMER AIR WORKS BACK IN FOR FRIDAY AND SATURDAY.
HIGHS FRIDAY WILL BE IN THE UPPER 30S TO LOWER 40S...WITH 40S FOR
HIGHS ON SATURDAY. TEMPERATURES WILL TAKE ANOTHER DOWN TURN ON
SUNDAY AS HIGHS WILL RANGE FROM THE MID 30S IN THE N TO MID 40S IN
NRN KY.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
CLOUD DECK AROUND 1000 TO 1500 FEET AGL ASSOCIATED WITH RESIDUAL
LOW LEVEL MOISTURE WILL KEEP CIGS MAINLY MVFR WITH A COUPLE IFR
SPOTS THROUGHOUT THE MORNING. AS THE DAY PROGRESSES THIS DECK
SHOULD THIN AS DRIER AIR BEGINS TO MIX INTO THE LOW LEVELS.
CURRENT FORECAST CALLS FOR CLOUDS TO SCATTER TO VFR BY THE LATE
MORNING STARTING ACROSS THE SOUTHERN TERMINALS KCVG/KLUK...AND
INTO THE EARLY AFTERNOON TOWARD THE NORTHERN TERMINALS.
AS LOW LEVEL WINDS BEGIN TO VEER OUT OF THE NORTHEAST LATE THIS
AFTERNOON...IT IS POSSIBLE THAT SOME OF THE MVFR CIGS MAY TRY TO
PUSH SOUTH ACROSS THE NORTHERN TERMINALS. KEPT THE FORECAST A BIT
MORE OPTIMISTIC WITH VFR CONDITIONS EXPECTED FROM THIS AFTERNOON
ONWARD THROUGH THE REST OF THE TAF PERIOD. THIS EVENING...A
DISTURBANCE PASSING BY TO OUR SOUTH WILL BRING VFR CLOUD COVER
ACROSS THE AREA. PRECIPITATION ASSOCIATED WITH THIS DISTURBANCE IS
EXPECTED TO REMAIN SOUTH OF OUR TERMINALS.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...JGL
NEAR TERM...JGL
SHORT TERM...JGL
LONG TERM...SITES
AVIATION...LATTO
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
406 AM EST MON JAN 14 2013
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION THROUGH THE FIRST PART OF
THE WORK WEEK. THIS WILL LEAD TO MAINLY DRY CONDITIONS AND MORE
SEASONABLE TEMPERATURES THROUGH WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE WILL BUILD INTO THE REGION THROUGH THIS AFTERNOON.
AS IT DOES...NORTH TO NORTHWEST LOW LEVEL FLOW WILL DECREASE BUT
WEAK CAA WILL CONTINUE THROUGH MUCH OF THE DAY. A FAIR AMOUNT OF
LOW CLOUDS ARE STILL IN PLACE ACROSS THE REGION BUT SATELLITE
IMAGES ARE INDICATING SOME BREAKS ACROSS PARTS OF OUR SOUTHWEST.
MAIN QUESTION FOR TODAY WILL BE HOW FAST THESE CLOUDS DISSIPATE.
THE RAP IS HANGING ON TO A FAIR AMOUNT OF LOW LEVEL MOISTURE
THROUGH THIS AFTERNOON. THIS IS PROBABLY OVERDONE AND PREFER
SOMETHING CLOSER TO WHAT THE NAM IS INDICATING ALTHOUGH THE WEAK
CAA MAY HELP KEEP THE CLOUDS AROUND A BIT LONGER. WILL THEREFORE
ALLOW FOR PARTIAL CLEARING HEADING THROUGH LATE MORNING INTO EARLY
AFTERNOON. 500 MB MOISTURE WILL INCREASE FROM THE SOUTHWEST LATER
THIS AFTERNOON AND THIS COULD ALLOW FOR AN INCREASE IN SOME
HIGHER LEVEL CLOUDS LATER TODAY. WITH WEAK CAA...EXPECT HIGHS
RANGING FROM THE UPPER 20S TO LOWER 30S IN THE NORTHWEST TO THE
MID AND UPPER 30S ACROSS THE SOUTHEAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
SURFACE HIGH PRESSURE WILL REMAIN ACROSS THE AREA TUESDAY INTO
WEDNESDAY...PROVIDING MAINLY DRY CONDITIONS. THE ONE EXCEPTION
COULD BE ACROSS OUR FAR SOUTHEAST AS A COUPLE OF SHORT WAVES RIDE
UP ALONG THE APPALACHIANS. THE MODELS HAVE TRENDED A BIT FARTHER
NORTH WITH THEIR NORTHERN PERIPHERY WITH THE INITIAL WAVE TONIGHT
AND THEN THE SECOND ONE FOR TUESDAY NIGHT. BOTH THE 00Z ECMWF AND
GFS ARE TRYING TO BRUSH A FEW OF OUR SOUTHEASTERN COUNTIES WITH
PCPN WHILE THE 00Z AND 06Z NAM ARE KEEPING EVERYTHING TO THE
SOUTH. GIVEN THE TRENDS...WILL GO AHEAD AND INTRODUCE SOME POPS
ACROSS THE FAR SOUTHEAST FOR TONIGHT AND TUESDAY NIGHT...BUT KEEP
THEM LOW AT THIS POINT. FORECAST SOUNDINGS ARE INDICATING THE
POSSIBILITY OF A RAIN/SNOW MIX WITH ANY PCPN BUT GIVEN THAT IT
WOULD BE AT NIGHT...IT MAY BE MORE LIKELY TO BE SNOW THAN RAIN.
CLOUDS WILL BE DEPENDENT ON JUST HOW FAR NORTH THESE WAVES MAKE IT
AND THIS WILL ALSO HAVE AN AFFECT ON LOW TEMPERATURES BOTH TONIGHT
AND TUESDAY NIGHT. WILL GO AHEAD AND ALLOW FOR A DECENT GRADIENT
BOTH NIGHTS FROM NORTHWEST TO SOUTHEAST ACROSS THE AREA.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE BUILDS BACK INTO THE OH AND TN VALLEYS THU INTO
FRI.
ENERGY KEEPS RUNNING THROUGH THE SUBTLE ERN U.S. LONGWAVE TROF OVER
THE WEEKEND. GFS AND ECMWF DIFFER ON THE STRENGTH OF A SYSTEM ON
SATURDAY....BUT BOTH PUSH COOLER AIR IN ON SUNDAY WITH A TRAILING
COLD FRONT. ONCE AGAIN THE MOISTURE IS LOOKING LIMITED FOR
SUNDAY...SO KEPT THE FCST DRY.
COOLER AIR BEHIND WEDNESDAYS SYSTEM WILL FILTER IN FOR
THU...DROPPING HIGHS INTO 30S. THE SEE-SAW TEMPERATURES WILL
CONTINUE...AS A WARMER AIR WORKS BACK IN FOR FRIDAY AND SATURDAY.
HIGHS FRIDAY WILL BE IN THE UPPER 30S TO LOWER 40S...WITH 40S FOR
HIGHS ON SATURDAY. TEMPERATURES WILL TAKE ANOTHER DOWN TURN ON
SUNDAY AS HIGHS WILL RANGE FROM THE MID 30S IN THE N TO MID 40S IN
NRN KY.
&&
.AVIATION /09Z MONDAY THROUGH FRIDAY/...
MVFR CIGS WILL CONTINUE FOR THE MOST PART ACROSS THE AREA THROUGH
SUNRISE. A BREAK IN THE CLOUD COVER WILL ALLOW FOR A COUPLE OF
HOUR PERIOD OF VFR CONDITIONS DURING THE MIDDLE OF THE NIGHT FOR
ALL TERMINALS EXCEPT KLCK/KCMH. AFTER SUNRISE THE BACK EDGE OF
CLOUD COVER WILL SPREAD EAST ACROSS THE TERMINALS WITH VFR
CONDITIONS AND EXPECTED THEREAFTER FOR THE REMAINDER OF THE TAF
PERIOD. SOME VFR LOW TO MID LEVEL CLOUD COVER IS EXPECTED TO
SPREAD ACROSS THE AREA LATE MONDAY AFTERNOON AND EVENING.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...JGL
NEAR TERM...JGL
SHORT TERM...JGL
LONG TERM...SITES
AVIATION...LATTO
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1226 AM EST MON JAN 14 2013
.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE MIDWEST AND NOSE INTO THE OHIO
VALLEY FOR THE BEGINNING OF THE WEEK. A WEAK COLD FRONT WILL SKIRT
THE NORTHEAST OHIO VALLEY WEDNESDAY NIGHT AND THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
COLD FRONT EXTENDS ACROSS THE FAR EASTERN COUNTIES AND WILL MOVE
OUT OF THE AREA IN THE NEXT COUPLE OF HOURS. RADAR SHOWS A SHARP
EDGE TO THE RAIN WHICH IS LAGGING THE FRONT BY A FEW HOURS. EXPECT
THE RAIN TO COME TO AN END BY 06Z. WITH THIS QUICK CUTOFF IT
APPEARS THAT PRECIPITATION WILL END BEFORE TEMPERATURES ARE COLD
ENOUGH FOR ANY WINTRY MIX. TIGHT GRADIENT IMMEDIATELY BEHIND THE
COLD FRONT HAS RESULT IN GUSTY WINDS. THESE SHOULD GRADUALLY
DIMINISH AS GRADIENT RELAXES. SATELLITE SHOWS CLEARING WORKING
INTO WESTERN INDIANA. RAP FORECASTS SEEM TO HAVE A REASONABLE
HANDLE ON THIS LOW LEVEL MOISTURE. THIS SUGGESTS THAT CLEARING
WILL WORK INTO THE FORECAST AREA LATER TONIGHT. FORECAST LOWS LOOK
REASONABLE WITH SOME MINOR ADJUSTMENTS TO TEMPERATURE DROP.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/...
I WAS UNABLE TO GO AS LOW ON THE CLOUD COVER WITH THE HIGH
PRESSURE BUILDING IN AS I WOULD LIKE. THOUGHT THE MOISTURE
BUILDING IN FROM THE NORTHWEST ON TUESDAY AND THE INCREASED
MOISTURE FROM THE SOUTHEAST ON MONDAY WOULD BATTLE FOR AT LEAST
SOME CLOUD COVER OVER THE REST OF THE CWA FOR SOME POINT IN TIME.
A VORTICITY MAXIMA IS NOTED SOMEWHAT AT H5 AND WILL SKIRT
SOUTHEAST CWA MONDAY EVENING...INCREASING THE THREAT FOR A PASSING
SNOW SHOWER FOR JUST A FEW COUNTIES SOUTH OF CHILLICOTHE AND EAST
OF MAYSVILLE. BOTH NAM AND GFS ARE HINTING AT A WEAK SHORTWAVE
WITH THIS VORT IN THE MEAN SOUTHWEST FLOW.
HIGH PRESSURE STRENGTHENING IN THE WAKE OF THE COLD FRONT WILL
HELP USHER IN MORE SEASONAL AND SIGNIFICANTLY COLDER TEMPERATURES
TO THE REGION.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
FORECAST PERIOD BEGINS WITH SFC HIGH PRESSURE RIDGING OVER THE FA.
THIS RIDGING GETS SHUNTED E QUICKLY ON WEDNESDAY AS A CDFNT SWINGS
THRU THE GREAT LAKES WED AFTN. MODELS ARE KEEPING THE BEST LIFT N OF
THE FA WITH THIS SYSTEM...SO KEPT THE FCST DRY. HIGH PRESSURE BUILDS
BACK INTO THE OH AND TN VALLEYS THU INTO FRI.
ENERGY KEEPS RUNNING THROUGH THE SUBTLE ERN U.S. LONGWAVE TROF OVER
THE WEEKEND. GFS AND ECMWF DIFFER ON THE STRENGTH OF A SYSTEM ON
SATURDAY....BUT BOTH PUSH COOLER AIR IN ON SUNDAY WITH A TRAILING
COLD FRONT. ONCE AGAIN THE MOISTURE IS LOOKING LIMITED FOR
SUNDAY...SO KEPT THE FCST DRY.
AS FOR TEMPERATURES...THE HIGH PRESSURE RIDGE ON WEDNESDAY WILL
ALLOW HIGHS TO CREEP INTO THE UPPER 30S TO LOWER 40S. COOLER AIR
BEHIND WEDNESDAYS SYSTEM WILL FILTER IN FOR THU...DROPPING HIGHS
INTO 30S. THE SEE-SAW TEMPERATURES WILL CONTINUE...AS A WARMER AIR
WORKS BACK IN FOR FRIDAY AND SATURDAY. HIGHS FRIDAY WILL BE IN THE
UPPER 30S TO LOWER 40S...WITH 40S FOR HIGHS ON SATURDAY.
TEMPERATURES WILL TAKE ANOTHER DOWN TURN ON SUNDAY AS HIGHS WILL
RANGE FROM THE MID 30S IN THE N TO MID 40S IN NRN KY.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
MVFR CIGS WILL CONTINUE FOR THE MOST PART ACROSS THE AREA THROUGH
SUNRISE. A BREAK IN THE CLOUD COVER WILL ALLOW FOR A COUPLE OF
HOUR PERIOD OF VFR CONDITIONS DURING THE MIDDLE OF THE NIGHT FOR
ALL TERMINALS EXCEPT KLCK/KCMH. AFTER SUNRISE THE BACK EDGE OF
CLOUD COVER WILL SPREAD EAST ACROSS THE TERMINALS WITH VFR
CONDITIONS AND EXPECTED THEREAFTER FOR THE REMAINDER OF THE TAF
PERIOD. SOME VFR LOW TO MID LEVEL CLOUD COVER IS EXPECTED TO
SPREAD ACROSS THE AREA LATE MONDAY AFTERNOON AND EVENING.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...FRANKS
NEAR TERM...
SHORT TERM...FRANKS
LONG TERM...SITES
AVIATION...LATTO
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
435 PM MST TUE JAN 15 2013
.AVIATION...00Z TAFS
SHSN WILL CONTINUE MOVING ACROSS THE AREA THIS EVENING BRINGING
IFR/LIFR CIGS/VSBYS AT TIMES. PATCHY FZDZ MAY OCCUR OVER THE
UPSLOPE AREAS OF THE BLACK HILLS. OUTSIDE OF THE MAIN SHSN
BANDS...MVFR CIGS WILL PREVAIL. CONDITIONS WILL IMPROVE OVERNIGHT
AS SUBSIDENCE TAKES OVER AND PUSHES PRECIPITATION EAST OF THE
REGION.
&&
.PREV DISCUSSION... /ISSUED 250 PM MST TUE JAN 15 2013/
DISCUSSION...VIGOROUS DEEP LAYER WAA AND HEIGHT RISES ONGOING
ACROSS THE FA...WITH UPSLOPE ENHANCEMENT BEGINNING TO REV UP. POTENT
UPPER LEVEL RIDGING AND ASSOCIATED WAA WILL CONTINUE THROUGH MOST OF
THE PERIOD...ALTHOUGH A PASSING NORTHERN STREAM DISTURBANCE WILL
OFFER A SHORT LULL IN WAA ACROSS THE NORTHERN HALF OF THE FA
WED...WITH WAA BEGINNING TO SPREAD OVER THE REGION AGAIN WED NIGHT
THUR AS THE REGION REMAINS ON THE WARM SIDE OF A VERY STRONG
BAROCLINIC ZONE. NEAR SATURATED WAA WILL CONTINUE THROUGH THIS
EVENING...BEFORE DRIER AIR ADVECTS INTO THE FA...SUPPORTING AN END
TO UPGLIDE/UPSLOPE INDUCED SNOW.
STRONG LOW CENTERED OMEGA MAX IS OFFERING STAUNCH LOW LEVEL LIFT IN
A NEAR SATURATED BL...WITH A RISING FROUDE NUMBER IN THE NORTHERN
BLACK HILLS. RAP POINT SOUNDINGS IN FAR WESTERN LAWRENCE COUNTY
INDICATE A DEEPLY SATURATED BL. HOWEVER...WAA IS SHUNTING THE LAYER
OF MAXIMUM OMEGA OUT OF THE DGZ INTO INCREASINGLY WARMER AIR. THIS
HAS ALLOWED THE PRODUCTION OF FREEZING DRIZZLE AT TIMES...WHICH IS
EXPECTED TO MIX WITH UPSLOPE SNOWS THROUGH THE AFTERNOON/EVENING..AS
LL PROFILES WARM AND MID LEVEL DRYING COMMENCES. SNOW MAY MIX WITH
OR CHANGE OVER TO ALL FREEZING DRIZZLE AT TIMES...ESP WITH
OSCILLATING INTENSITY OF UPSLOPE ENHANCEMENT AND ANY SEEDER-FEEDER
PROCESS. STILL EXPECT ANOTHER 1-3 INCHES THROUGH THE EVENING IN TH
ADV...WITH LOCALLY HIGHER AMOUNTS WHERE SNOW PERSISTS...ALTHOUGH ZL
MIXING MAY LIMIT SNOWS SIG IN SOME AREAS. WILL KEEP THE ADV GOING
THROUGH THE CURRENT EXPIRATION TIME.
BREEZY CONDITIONS CAN BE EXPECTED THROUGH WED GIVEN THE LL BAROCLINIC
ZONE IN PLACE ACROSS THE REGION/EXPECTED PRESSURE FALLS...ALTHOUGH
WAA WILL OFFSET THE INTENSITY OF WINDS TONIGHT. A LITTLE BETTER
MIXING AND WEAK CAA ACROSS THE NORTH WILL ALLOW FOR BREEZY
CONDITIONS OVER THE SD PLAINS ON WED.
DRIER AIR WILL WORK INTO THE AREA...WITH SIG AMOUNTS OF HIGH CLOUDS
EXPECTED TO REMAIN GIVEN THE LOCATION OF THE UPPER JET. IN
ADDITION...A WEAK SECONDARY COLD FRONT/TROUGH WILL ADVECT THROUGH
THE AREA...SUPPORTING SOME MID CLOUD ACROSS THE NORTH...WITH
DECREASING CLOUDS THROUGH THE WED PERIOD. ALTHOUGH VERY WARM
PROFILES ARE PROGGED JUST ABOVE THE SFC...HIGH CLOUD COVER MAY LIMIT
T RISES TO A POINT WED...ESP AWAY FROM DOWNSLOPE AREAS AND WHERE A
DEEPER SNOW PACK IS IN PLACE. LOWS WILL REMAIN TRICKY...ESP WED
NIGHT WHEN WAA AND A LINGERING PRESSURE GRADIENT IN PLACE IS
ALLOWING SOME MODEL PROGS TO FORECAST MUCH WARMER TEMPS THAN SOME
OTHER SOLUTIONS. HAVE SIDED SOME TOWARD THIS WARMER SOLUTION WHICH
HAS BEEN EVIDENT THE LAST SEVERAL RUNS...ALTHOUGH QUESTIONS ON SNOW
COVER AND DECOUPLING REMAIN. HAVE INCORPORATED SOME DOWNSLOPE
EFFECTS ON THUR/S HIGHS WHICH WILL AGAIN REMAIN TRICKY.
EXTENDED...FAST NORTHWEST FLOW WILL CONTINUE OVER THE NORTHERN
PLAINS THROUGH EARLY NEXT WEEK. THE FORECAST AREA WILL REMAIN UNDER
THE INFLUENCE OF THE WESTERN RIDGE FOR ONE MORE DAY ON FRIDAY...WITH
DRY CONDITIONS AND MILD TEMPERATURES. CHANGES WILL COME THIS WEEKEND
AS A COMPACT SHORTWAVE DIVES THROUGH NORTHERN MINNESOTA...DRAGGING A
STRONG COLD FRONT ACROSS THE DAKOTAS FRIDAY NIGHT INTO SATURDAY.
TEMPERATURES WILL COOL DRAMATICALLY BY SUNDAY AND MONDAY AS ARCTIC
AIR SETTLES ACROSS THE NORTHERN PLAINS. ANOTHER WEAKER SHORTWAVE
WILL CROSS THE DAKOTAS ON SUNDAY...GIVING THE AREA A CHANCE FOR
LIGHT SNOW THROUGH SUNDAY NIGHT.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING FOR CENTRAL
BLACK HILLS-NORTHERN BLACK HILLS.
WY...WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING FOR WYOMING
BLACK HILLS.
&&
$$
SHORT TERM...WFO UNR
LONG TERM...WFO UNR
AVIATION...HELGESON
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1130 AM CST MON JAN 14 2013
.DISCUSSION.../ISSUED AT 1130 AM CST/
UPDATED THE AFTERNOON GRIDS TO INCLUDE A FEW FLURRIES FOR OUR FAR
NORTHERN ZONES ALONG HIGHWAY 14. MID LEVEL CLOUDINESS WILL BE
PREVALENT IN THOSE AREAS ASSOCIATED WITH A SLOW MOVING SHORT WAVE.
BUT CURRENT THINKING IS THAT LOWER CLOUDS WILL STAY TO THE NORTH OF
OUR FORECAST AREA WHICH WOULD AID IN PRODUCING POCKETS OF LIGHT
SNOWFALL WHICH COULD MEASURE A LITTLE BIT. /MJF
&&
.AVIATION.../FOR THE 18Z TAF ISSUANCE/
VFR WILL BE THE PRIMARY CATEGORY THIS AFTERNOON...TONIGHT AND
TUESDAY MORNING. MID LEVEL CLOUDS WILL STREAM ACROSS OUR FAR
NORTHERN ZONES THIS AFTERNOON...AND EVEN SOMEWHAT TONIGHT...
ASSOCIATED WITH A MID LEVEL SHORT WAVE WHICH IS MOVING VERY SLOWLY
ACROSS THIS AREA. IN ADDITION...SOME LOWER VFR CEILINGS ARE LIKELY
TO MOVE NORTHWARD INTO THE SIOUX CITY AND STORM LAKE IOWA AREAS
OVERNIGHT AND LATE TONIGHT. THOSE POTENTIAL CLOUDS ARE CURRENTLY
EVIDENT IN SOUTHWEST NEB AND NORTHEAST CO. OTHERWISE...WITH A VERY
LIGHT SOUTH WIND...SOMETIMES SOME MVFR HAZE OCCURS IN THE MORNING
HOURS. SO FOR NOW PUT THAT POSSIBILITY IN A TEMPO GROUP FOR OUR
THREE TAF SITES. /MJF
&&
.PREVIOUS DISCUSSION.../ISSUED AT 415 AM CST/
FAIRLY QUIET WEEK AHEAD...WITH MAIN ENERGY FROM A COUPLE OF WAVES
EXPECTED TO REMAIN NORTH OF THE AREA...LEAVING TEMPERATURES AS
PRIMARY CONCERN THROUGH NEXT WEEKEND.
FOR TODAY...WEAK WAVE SLIDING NORTHEAST ACROSS OUR AREA AHEAD OF
MID-UPPER TROUGH DROPPING SOUTHEAST INTO THE UPPER MIDWEST. WITH
COLD AIR MASS STILL IN PLACE AND WEAK LIFT FROM THIS WAVE...STILL
SEEING FLURRIES BEING SQUEEZED OUT OF ANY LOWER/DEEPER MOISTURE
LAYERS. RAP SEEMS TO BE HANDLING THE MOISTURE FAIRLY WELL...AND
KEEPS DEEPER MOISTURE ACROSS CENTRAL/NORTHERN CWA THIS MORNING...
SHIFTING EAST OF THE AREA THROUGH THE AFTERNOON. DEEPER MOISTURE
AGAIN LIES IN FAVORABLE TEMPERATURE ZONE FOR ICE PRODUCTION /A FEW
DEGREES EITHER SIDE OF -15C/...THUS HAVE ADDED SCATTERED FLURRIES
ALONG/NORTH OF I-90 THROUGH MIDDAY.
TEMPERATURES SHOULD REBOUND A BIT FROM WEEKEND CHILL AS WARMER LOW
LEVEL AIR BEGINS TO WORK INTO THE AREA THIS AFTERNOON. STILL ONE
MORE DAY BELOW NORMAL THOUGH... WITH HIGHS IN THE TEENS TO LOWER
20S. ONE THING OF NOTE ON TEMPS THROUGHOUT MUCH OF THE FORECAST...
NAM/GFS APPEAR TO HAVE POORLY INITIALIZED SNOW COVER IN THE MODEL...
WHICH SEEMS TO BE HAVING A LARGE EFFECT ON THEIR RESPECTIVE SURFACE
TEMPERATURE FORECASTS... SEEN BOTH IN THE RAW MODELS/MOS OUTPUT...
THOUGH SOMEWHAT LESSER EXTENT IN THE LATTER. THUS HAVE CHOSEN TO
FAVOR WARMER GEM/ECMWF TEMPERATURES THROUGH MOST OF THE WEEK...
ESPECIALLY THROUGH FRIDAY WHEN WARM AIR ALOFT REMAINS IN PLACE.
NEXT WAVE MOVES ACROSS THE REGION TUESDAY/TUESDAY NIGHT. STRONG WARM
ADVECTION WILL LEAD TO POTENTIAL FOR A LITTLE LIGHT SNOW OR FLURRIES
AHEAD OF THE WARM AIR...WHICH WILL SPREAD ACROSS THE FORECAST AREA
IN EARNEST TUESDAY NIGHT. LITTLE ACCUMULATION EXPECTED...WITH MAYBE
A QUARTER INCH OR SO ALONG THE HIGHWAY 14 CORRIDOR. STOUT SOUTHWEST
FLOW AHEAD OF THE WARM FRONT WILL RESULT IN GUSTY WINDS ATOP AND
DOWNSTREAM OF THE BUFFALO RIDGE MUCH OF THE NIGHT. EXPECT EARLY
EVENING LOWS FROM AROUND 20 IN THE EAST TO THE MID-UPPER 20S WEST OF
THE JAMES VALLEY...WITH MOST AREAS WARMING TO NEAR FREEZING OR JUST
SHY BY DAYBREAK WEDNESDAY AS WINDS TURN TO THE WEST BEHIND THE WARM
FRONT. STILL LOOKS LIKE A MILD DAY WITH TEMPS ONLY WARMING A FEW
MORE DEGREES THROUGH THE DAY TO HIGHS OF 35 TO 45.
BACKDOOR COOL FRONT DROPS THROUGH NORTHEAST PORTIONS OF THE FORECAST
AREA WEDNESDAY NIGHT/THURSDAY. TEMPERATURES STILL EXPECTED TO BE
ABOVE NORMAL THURSDAY THOUGH...WITH HIGHS UPPER 20S NORTHEAST TO THE
MID 30S THROUGH THE MISSOURI VALLEY. GEM/ECMWF BOTH SHOWING ANOTHER
WARM PUSH FRIDAY AHEAD OF STRONGER PUSH OF COLD AIR EXPECTED NEXT
WEEKEND. HAVE NUDGED TEMPERATURES A FEW DEGREES ABOVE GENERAL MODEL
CONSENSUS...THOUGH COULD BE EVEN WARMER IF 14/00Z ECMWF PANS OUT.
A COUPLE OF QUICK MOVING WAVES DIVE SOUTHEAST ACROSS NORTH DAKOTA
AND NORTHERN MINNESOTA DURING THE LONGER RANGE. THE FIRST WEAKER
WAVE MOVES THROUGH THURSDAY NIGHT...LEAVING A TIGHTENING THERMAL
GRADIENT WHICH NEXT STRONGER WAVE CAN WORK WITH SATURDAY. THIS WAVE
WILL PUSH THE ARCTIC FRONT SOUTH THROUGH THE REGION...BRINGING A
RETURN TO BELOW NORMAL TEMPERATURES BY THE LATTER HALF OF NEXT
WEEKEND. AS WAS MENTIONED ABOVE...ENERGY APPEARS TO REMAIN WELL
NORTH OF OUR AREA AT THIS TIME...SO WILL KEEP THE LONGER RANGE DRY
FOR NOW. HOWEVER WILL HAVE TO WATCH FOR POTENTIAL OF SOME LIGHT SNOW
SUNDAY AS YET ANOTHER WAVE DROPS INTO THE ARCTIC AIR MASS WHICH IS
EXPECTED TO PUSH BACK INTO THE REGION BY THEN.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1039 AM CST MON JAN 14 2013
.DISCUSSION.../ISSUED AT 1040 AM CST/
MAINLY TWEAKED THE FORECAST TO REDUCE CLOUD COVER OVER MUCH OF THE
FORECAST AREA...MINUS OUR NORTHERN ZONES WHERE MID LEVEL CLOUDINESS
SHOULD ADVECT EASTWARD THROUGH THE COURSE OF THE DAY. BUT OTHERWISE
THIS AFTERNOON HIGHS SHOULD BE CLOSE. /MJF
&&
.AVIATION.../FOR THE 12Z TAF ISSUANCE/
AN AREA OF CEILINGS 1-3K FEET SHOULD BE EXITING SOUTHWEST MN BY 15Z.
OTHERWISE VFR IS EXPECTED OVER THE AREA THROUGH 15/12Z. AREAS OF
CEILINGS 3-5K FEET WILL PASS OVER THE AREA NORTH OF INTERSTATE 90
THROUGH 15/06Z WITH CEILINGS ELSEWHERE UNRESTRICTED OR ABOVE 5K
FEET. IT APPEARS AIR WILL BE TOO DRY FOR PATCHY FOG IN LIGHT WIND
REGIME NEAR END OF PERIOD AT 15/12Z. SURFACE WINDS SHOULD BE 10
KNOTS OR LESS THROUGH 15/12Z.
&&
.PREVIOUS DISCUSSION.../ISSUED AT 415 AM CST/
FAIRLY QUIET WEEK AHEAD...WITH MAIN ENERGY FROM A COUPLE OF WAVES
EXPECTED TO REMAIN NORTH OF THE AREA...LEAVING TEMPERATURES AS
PRIMARY CONCERN THROUGH NEXT WEEKEND.
FOR TODAY...WEAK WAVE SLIDING NORTHEAST ACROSS OUR AREA AHEAD OF
MID-UPPER TROUGH DROPPING SOUTHEAST INTO THE UPPER MIDWEST. WITH
COLD AIR MASS STILL IN PLACE AND WEAK LIFT FROM THIS WAVE...STILL
SEEING FLURRIES BEING SQUEEZED OUT OF ANY LOWER/DEEPER MOISTURE
LAYERS. RAP SEEMS TO BE HANDLING THE MOISTURE FAIRLY WELL...AND
KEEPS DEEPER MOISTURE ACROSS CENTRAL/NORTHERN CWA THIS MORNING...
SHIFTING EAST OF THE AREA THROUGH THE AFTERNOON. DEEPER MOISTURE
AGAIN LIES IN FAVORABLE TEMPERATURE ZONE FOR ICE PRODUCTION /A FEW
DEGREES EITHER SIDE OF -15C/...THUS HAVE ADDED SCATTERED FLURRIES
ALONG/NORTH OF I-90 THROUGH MIDDAY.
TEMPERATURES SHOULD REBOUND A BIT FROM WEEKEND CHILL AS WARMER LOW
LEVEL AIR BEGINS TO WORK INTO THE AREA THIS AFTERNOON. STILL ONE
MORE DAY BELOW NORMAL THOUGH... WITH HIGHS IN THE TEENS TO LOWER
20S. ONE THING OF NOTE ON TEMPS THROUGHOUT MUCH OF THE FORECAST...
NAM/GFS APPEAR TO HAVE POORLY INITIALIZED SNOW COVER IN THE MODEL...
WHICH SEEMS TO BE HAVING A LARGE EFFECT ON THEIR RESPECTIVE SURFACE
TEMPERATURE FORECASTS... SEEN BOTH IN THE RAW MODELS/MOS OUTPUT...
THOUGH SOMEWHAT LESSER EXTENT IN THE LATTER. THUS HAVE CHOSEN TO
FAVOR WARMER GEM/ECMWF TEMPERATURES THROUGH MOST OF THE WEEK...
ESPECIALLY THROUGH FRIDAY WHEN WARM AIR ALOFT REMAINS IN PLACE.
NEXT WAVE MOVES ACROSS THE REGION TUESDAY/TUESDAY NIGHT. STRONG WARM
ADVECTION WILL LEAD TO POTENTIAL FOR A LITTLE LIGHT SNOW OR FLURRIES
AHEAD OF THE WARM AIR...WHICH WILL SPREAD ACROSS THE FORECAST AREA
IN EARNEST TUESDAY NIGHT. LITTLE ACCUMULATION EXPECTED...WITH MAYBE
A QUARTER INCH OR SO ALONG THE HIGHWAY 14 CORRIDOR. STOUT SOUTHWEST
FLOW AHEAD OF THE WARM FRONT WILL RESULT IN GUSTY WINDS ATOP AND
DOWNSTREAM OF THE BUFFALO RIDGE MUCH OF THE NIGHT. EXPECT EARLY
EVENING LOWS FROM AROUND 20 IN THE EAST TO THE MID-UPPER 20S WEST OF
THE JAMES VALLEY...WITH MOST AREAS WARMING TO NEAR FREEZING OR JUST
SHY BY DAYBREAK WEDNESDAY AS WINDS TURN TO THE WEST BEHIND THE WARM
FRONT. STILL LOOKS LIKE A MILD DAY WITH TEMPS ONLY WARMING A FEW
MORE DEGREES THROUGH THE DAY TO HIGHS OF 35 TO 45.
BACKDOOR COOL FRONT DROPS THROUGH NORTHEAST PORTIONS OF THE FORECAST
AREA WEDNESDAY NIGHT/THURSDAY. TEMPERATURES STILL EXPECTED TO BE
ABOVE NORMAL THURSDAY THOUGH...WITH HIGHS UPPER 20S NORTHEAST TO THE
MID 30S THROUGH THE MISSOURI VALLEY. GEM/ECMWF BOTH SHOWING ANOTHER
WARM PUSH FRIDAY AHEAD OF STRONGER PUSH OF COLD AIR EXPECTED NEXT
WEEKEND. HAVE NUDGED TEMPERATURES A FEW DEGREES ABOVE GENERAL MODEL
CONSENSUS...THOUGH COULD BE EVEN WARMER IF 14/00Z ECMWF PANS OUT.
A COUPLE OF QUICK MOVING WAVES DIVE SOUTHEAST ACROSS NORTH DAKOTA
AND NORTHERN MINNESOTA DURING THE LONGER RANGE. THE FIRST WEAKER
WAVE MOVES THROUGH THURSDAY NIGHT...LEAVING A TIGHTENING THERMAL
GRADIENT WHICH NEXT STRONGER WAVE CAN WORK WITH SATURDAY. THIS WAVE
WILL PUSH THE ARCTIC FRONT SOUTH THROUGH THE REGION...BRINGING A
RETURN TO BELOW NORMAL TEMPERATURES BY THE LATTER HALF OF NEXT
WEEKEND. AS WAS MENTIONED ABOVE...ENERGY APPEARS TO REMAIN WELL
NORTH OF OUR AREA AT THIS TIME...SO WILL KEEP THE LONGER RANGE DRY
FOR NOW. HOWEVER WILL HAVE TO WATCH FOR POTENTIAL OF SOME LIGHT SNOW
SUNDAY AS YET ANOTHER WAVE DROPS INTO THE ARCTIC AIR MASS WHICH IS
EXPECTED TO PUSH BACK INTO THE REGION BY THEN.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
450 AM CST MON JAN 14 2013
.DISCUSSION...
FAIRLY QUIET WEEK AHEAD...WITH MAIN ENERGY FROM A COUPLE OF WAVES
EXPECTED TO REMAIN NORTH OF THE AREA...LEAVING TEMPERATURES AS
PRIMARY CONCERN THROUGH NEXT WEEKEND.
FOR TODAY...WEAK WAVE SLIDING NORTHEAST ACROSS OUR AREA AHEAD OF
MID-UPPER TROUGH DROPPING SOUTHEAST INTO THE UPPER MIDWEST. WITH
COLD AIR MASS STILL IN PLACE AND WEAK LIFT FROM THIS WAVE...STILL
SEEING FLURRIES BEING SQUEEZED OUT OF ANY LOWER/DEEPER MOISTURE
LAYERS. RAP SEEMS TO BE HANDLING THE MOISTURE FAIRLY WELL...AND
KEEPS DEEPER MOISTURE ACROSS CENTRAL/NORTHERN CWA THIS MORNING...
SHIFTING EAST OF THE AREA THROUGH THE AFTERNOON. DEEPER MOISTURE
AGAIN LIES IN FAVORABLE TEMPERATURE ZONE FOR ICE PRODUCTION /A FEW
DEGREES EITHER SIDE OF -15C/...THUS HAVE ADDED SCATTERED FLURRIES
ALONG/NORTH OF I-90 THROUGH MIDDAY.
TEMPERATURES SHOULD REBOUND A BIT FROM WEEKEND CHILL AS WARMER LOW
LEVEL AIR BEGINS TO WORK INTO THE AREA THIS AFTERNOON. STILL ONE
MORE DAY BELOW NORMAL THOUGH... WITH HIGHS IN THE TEENS TO LOWER
20S. ONE THING OF NOTE ON TEMPS THROUGHOUT MUCH OF THE FORECAST...
NAM/GFS APPEAR TO HAVE POORLY INITIALIZED SNOW COVER IN THE MODEL...
WHICH SEEMS TO BE HAVING A LARGE EFFECT ON THEIR RESPECTIVE SURFACE
TEMPERATURE FORECASTS... SEEN BOTH IN THE RAW MODELS/MOS OUTPUT...
THOUGH SOMEWHAT LESSER EXTENT IN THE LATTER. THUS HAVE CHOSEN TO
FAVOR WARMER GEM/ECMWF TEMPERATURES THROUGH MOST OF THE WEEK...
ESPECIALLY THROUGH FRIDAY WHEN WARM AIR ALOFT REMAINS IN PLACE.
NEXT WAVE MOVES ACROSS THE REGION TUESDAY/TUESDAY NIGHT. STRONG WARM
ADVECTION WILL LEAD TO POTENTIAL FOR A LITTLE LIGHT SNOW OR FLURRIES
AHEAD OF THE WARM AIR...WHICH WILL SPREAD ACROSS THE FORECAST AREA
IN EARNEST TUESDAY NIGHT. LITTLE ACCUMULATION EXPECTED...WITH MAYBE
A QUARTER INCH OR SO ALONG THE HIGHWAY 14 CORRIDOR. STOUT SOUTHWEST
FLOW AHEAD OF THE WARM FRONT WILL RESULT IN GUSTY WINDS ATOP AND
DOWNSTREAM OF THE BUFFALO RIDGE MUCH OF THE NIGHT. EXPECT EARLY
EVENING LOWS FROM AROUND 20 IN THE EAST TO THE MID-UPPER 20S WEST OF
THE JAMES VALLEY...WITH MOST AREAS WARMING TO NEAR FREEZING OR JUST
SHY BY DAYBREAK WEDNESDAY AS WINDS TURN TO THE WEST BEHIND THE WARM
FRONT. STILL LOOKS LIKE A MILD DAY WITH TEMPS ONLY WARMING A FEW
MORE DEGREES THROUGH THE DAY TO HIGHS OF 35 TO 45.
BACKDOOR COOL FRONT DROPS THROUGH NORTHEAST PORTIONS OF THE FORECAST
AREA WEDNESDAY NIGHT/THURSDAY. TEMPERATURES STILL EXPECTED TO BE
ABOVE NORMAL THURSDAY THOUGH...WITH HIGHS UPPER 20S NORTHEAST TO THE
MID 30S THROUGH THE MISSOURI VALLEY. GEM/ECMWF BOTH SHOWING ANOTHER
WARM PUSH FRIDAY AHEAD OF STRONGER PUSH OF COLD AIR EXPECTED NEXT
WEEKEND. HAVE NUDGED TEMPERATURES A FEW DEGREES ABOVE GENERAL MODEL
CONSENSUS...THOUGH COULD BE EVEN WARMER IF 14/00Z ECMWF PANS OUT.
A COUPLE OF QUICK MOVING WAVES DIVE SOUTHEAST ACROSS NORTH DAKOTA
AND NORTHERN MINNESOTA DURING THE LONGER RANGE. THE FIRST WEAKER
WAVE MOVES THROUGH THURSDAY NIGHT...LEAVING A TIGHTENING THERMAL
GRADIENT WHICH NEXT STRONGER WAVE CAN WORK WITH SATURDAY. THIS WAVE
WILL PUSH THE ARCTIC FRONT SOUTH THROUGH THE REGION...BRINGING A
RETURN TO BELOW NORMAL TEMPERATURES BY THE LATTER HALF OF NEXT
WEEKEND. AS WAS MENTIONED ABOVE...ENERGY APPEARS TO REMAIN WELL
NORTH OF OUR AREA AT THIS TIME...SO WILL KEEP THE LONGER RANGE DRY
FOR NOW. HOWEVER WILL HAVE TO WATCH FOR POTENTIAL OF SOME LIGHT SNOW
SUNDAY AS YET ANOTHER WAVE DROPS INTO THE ARCTIC AIR MASS WHICH IS
EXPECTED TO PUSH BACK INTO THE REGION BY THEN.
&&
.AVIATION.../FOR THE 12Z TAF ISSUANCE/
AN AREA OF CEILINGS 1-3K FEET SHOULD BE EXITING SOUTHWEST MN BY 15Z.
OTHERWISE VFR IS EXPECTED OVER THE AREA THROUGH 15/12Z. AREAS OF
CEILINGS 3-5K FEET WILL PASS OVER THE AREA NORTH OF INTERSTATE 90
THROUGH 15/06Z WITH CEILINGS ELSEWHERE UNRESTRICTED OR ABOVE 5K
FEET. IT APPEARS AIR WILL BE TOO DRY FOR PATCHY FOG IN LIGHT WIND
REGIME NEAR END OF PERIOD AT 15/12Z. SURFACE WINDS SHOULD BE 10
KNOTS OR LESS THROUGH 15/12Z.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
415 AM CST MON JAN 14 2013
.DISCUSSION...
FAIRLY QUIET WEEK AHEAD...WITH MAIN ENERGY FROM A COUPLE OF WAVES
EXPECTED TO REMAIN NORTH OF THE AREA...LEAVING TEMPERATURES AS
PRIMARY CONCERN THROUGH NEXT WEEKEND.
FOR TODAY...WEAK WAVE SLIDING NORTHEAST ACROSS OUR AREA AHEAD OF
MID-UPPER TROUGH DROPPING SOUTHEAST INTO THE UPPER MIDWEST. WITH
COLD AIR MASS STILL IN PLACE AND WEAK LIFT FROM THIS WAVE...STILL
SEEING FLURRIES BEING SQUEEZED OUT OF ANY LOWER/DEEPER MOISTURE
LAYERS. RAP SEEMS TO BE HANDLING THE MOISTURE FAIRLY WELL...AND
KEEPS DEEPER MOISTURE ACROSS CENTRAL/NORTHERN CWA THIS MORNING...
SHIFTING EAST OF THE AREA THROUGH THE AFTERNOON. DEEPER MOISTURE
AGAIN LIES IN FAVORABLE TEMPERATURE ZONE FOR ICE PRODUCTION /A FEW
DEGREES EITHER SIDE OF -15C/...THUS HAVE ADDED SCATTERED FLURRIES
ALONG/NORTH OF I-90 THROUGH MIDDAY.
TEMPERATURES SHOULD REBOUND A BIT FROM WEEKEND CHILL AS WARMER LOW
LEVEL AIR BEGINS TO WORK INTO THE AREA THIS AFTERNOON. STILL ONE
MORE DAY BELOW NORMAL THOUGH... WITH HIGHS IN THE TEENS TO LOWER
20S. ONE THING OF NOTE ON TEMPS THROUGHOUT MUCH OF THE FORECAST...
NAM/GFS APPEAR TO HAVE POORLY INITIALIZED SNOW COVER IN THE MODEL...
WHICH SEEMS TO BE HAVING A LARGE EFFECT ON THEIR RESPECTIVE SURFACE
TEMPERATURE FORECASTS... SEEN BOTH IN THE RAW MODELS/MOS OUTPUT...
THOUGH SOMEWHAT LESSER EXTENT IN THE LATTER. THUS HAVE CHOSEN TO
FAVOR WARMER GEM/ECMWF TEMPERATURES THROUGH MOST OF THE WEEK...
ESPECIALLY THROUGH FRIDAY WHEN WARM AIR ALOFT REMAINS IN PLACE.
NEXT WAVE MOVES ACROSS THE REGION TUESDAY/TUESDAY NIGHT. STRONG WARM
ADVECTION WILL LEAD TO POTENTIAL FOR A LITTLE LIGHT SNOW OR FLURRIES
AHEAD OF THE WARM AIR...WHICH WILL SPREAD ACROSS THE FORECAST AREA
IN EARNEST TUESDAY NIGHT. LITTLE ACCUMULATION EXPECTED...WITH MAYBE
A QUARTER INCH OR SO ALONG THE HIGHWAY 14 CORRIDOR. STOUT SOUTHWEST
FLOW AHEAD OF THE WARM FRONT WILL RESULT IN GUSTY WINDS ATOP AND
DOWNSTREAM OF THE BUFFALO RIDGE MUCH OF THE NIGHT. EXPECT EARLY
EVENING LOWS FROM AROUND 20 IN THE EAST TO THE MID-UPPER 20S WEST OF
THE JAMES VALLEY...WITH MOST AREAS WARMING TO NEAR FREEZING OR JUST
SHY BY DAYBREAK WEDNESDAY AS WINDS TURN TO THE WEST BEHIND THE WARM
FRONT. STILL LOOKS LIKE A MILD DAY WITH TEMPS ONLY WARMING A FEW
MORE DEGREES THROUGH THE DAY TO HIGHS OF 35 TO 45.
BACKDOOR COOL FRONT DROPS THROUGH NORTHEAST PORTIONS OF THE FORECAST
AREA WEDNESDAY NIGHT/THURSDAY. TEMPERATURES STILL EXPECTED TO BE
ABOVE NORMAL THURSDAY THOUGH...WITH HIGHS UPPER 20S NORTHEAST TO THE
MID 30S THROUGH THE MISSOURI VALLEY. GEM/ECMWF BOTH SHOWING ANOTHER
WARM PUSH FRIDAY AHEAD OF STRONGER PUSH OF COLD AIR EXPECTED NEXT
WEEKEND. HAVE NUDGED TEMPERATURES A FEW DEGREES ABOVE GENERAL MODEL
CONSENSUS...THOUGH COULD BE EVEN WARMER IF 14/00Z ECMWF PANS OUT.
A COUPLE OF QUICK MOVING WAVES DIVE SOUTHEAST ACROSS NORTH DAKOTA
AND NORTHERN MINNESOTA DURING THE LONGER RANGE. THE FIRST WEAKER
WAVE MOVES THROUGH THURSDAY NIGHT...LEAVING A TIGHTENING THERMAL
GRADIENT WHICH NEXT STRONGER WAVE CAN WORK WITH SATURDAY. THIS WAVE
WILL PUSH THE ARCTIC FRONT SOUTH THROUGH THE REGION...BRINGING A
RETURN TO BELOW NORMAL TEMPERATURES BY THE LATTER HALF OF NEXT
WEEKEND. AS WAS MENTIONED ABOVE...ENERGY APPEARS TO REMAIN WELL
NORTH OF OUR AREA AT THIS TIME...SO WILL KEEP THE LONGER RANGE DRY
FOR NOW. HOWEVER WILL HAVE TO WATCH FOR POTENTIAL OF SOME LIGHT SNOW
SUNDAY AS YET ANOTHER WAVE DROPS INTO THE ARCTIC AIR MASS WHICH IS
EXPECTED TO PUSH BACK INTO THE REGION BY THEN.
&&
.AVIATION.../FOR THE 06Z TAF ISSUANCE/
AN AREA OF STRATUS AROUND 3000 FEET WILL AFFECT THE NORTHERN CWA
THROUGH THE OVERNIGHT HOURS AFFECTING BOTH THE KHON AND KFSD
TERMINALS. THERE MAYBE A FEW FLURRIES ASSOCIATED WITH THIS BAND OF
STRATUS...BUT IS NOT EXPECTED TO REDUCE VISIBILITY. THEREAFTER..VFR
CONDITIONS ARE EXPECTED TO PREVAIL WITH LIGHT WESTERLY WINDS
BECOMING SOUTHWEST.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
331 PM CST MON JAN 14 2013
.TONIGHT AND TUESDAY...FORECAST CONFIDENCE...HIGH
AN AREA OF LOW LEVEL CLOUDS WILL LIKELY AFFECT THE NORTHWEST HALF OF
THE FORECAST AREA LATE THIS AFTERNOON AND INTO TONIGHT. HIGH LEVEL
CLOUDS ARE POSSIBLE ELSEWHERE. THE LOW LEVEL CLOUDS SHOULD MOVE ON
OR SCATTER OUT BY LATE IN THE NIGHT...WITH SOME MID LEVEL CLOUDS
LINGERING TUESDAY MORNING. SKIES SHOULD BECOME MOSTLY SUNNY BY THE
AFTERNOON.
LOWS A LITTLE TRICKY TONIGHT...ALL DEPENDING ON HOW LONG CLOUDS
STICK AROUND...AS WINDS WILL BE LIGHT. GENERALLY WENT WITH A
CONSENSUS FOR LOWS...AS THE ECMWF/GFS/NAM SOLUTIONS NOT TOO FAR
APART. COULD SEE TEMPS GET A FEW DEGREES COLDER THAN EXPECTED IF
SKIES CLEAR UP SOONER THAN EXPECTED...RESULTING IN A LONGER PERIOD
OF GOOD RADIATIONAL COOLING CONDITIONS. HIGH TEMPS SHOULD BE BACK
AROUND NORMAL TUESDAY...MAYBE EVEN A DEGREE OR TWO ABOVE AVERAGE
VALUES FOR MID JANUARY.
.SHORT TERM...TUESDAY NIGHT THROUGH THURSDAY.
MID TO UPPER LEVEL TROUGH AXES SHIFT EAST...WITH SHORT WAVE DROPPING
SE TUESDAY NIGHT/WEDNESDAY IN LEFT EXIT REGION OF UPPER LEVEL JET
MAX TOPPING WESTERN RIDGE AND NOSING INTO THE UPPER MIDWEST. AFTER
THIS WAVE CLEARS THE REGION...MODELS VARY IN PLACEMENT OF CHANNELED
VORTICITY IN CONFLUENT FLOW UNDER HUDSON BAY POLAR VORTEX FOR THE
REST OF THE SHORT TERM BUT GENERALLY KEEP IT TIED TO THE UPPER
JET...STAYING NORTH OF FORECAST AREA.
TUESDAY NIGHT AND WEDNESDAY...FORECAST CONFIDENCE MEDIUM.
TEMPERATURES FALL TUESDAY EVENING WITH READINGS HOLDING STEADY OR
RISING AFTER LOWS ARE REACHED AROUND MIDNIGHT AS SOUTHWEST WINDS
INCREASE AHEAD OF APPROACHING SHORT WAVE. LOCATION OF BEST FORCING
WITH WAVE VARIES WITH MODEL TRACK AND STRENGTH DIFFERENCES.
CONSENSUS KEEPS THE BETTER CHANCES FOR ACCUMULATING SNOW ACROSS NRN
WI...WHICH LEADS TO CHANCE OF LIGHT SNOW IN THE FAR NORTH AND SLIGHT
CHANCE ELSEWHERE MAINLY WEDNESDAY MORNING. BRIEF PERIOD OF LIFT AND
DEEP MOISTURE INTO THE DENDRITE GROWTH ZONE...ALONG WITH
PRECIPITABLE WATER ONLY REACHING 1/3 INCH SO DURING MOST FAVORABLE
TIME FOR PRECIPITATION...MEANS MINIMAL ACCUMULATIONS OF A FEW TENTHS
OF AN INCH AT MOST.
GUSTY WINDS ON WEDNESDAY WITH TIGHT GRADIENT AROUND SOUTHERN CANADA
LOW. AGAIN A CONSENSUS BLEND TEMPERING THE STRONGER NAM WINDS BUT
THIS STILL BRINGS 15 TO 25 MPH SOUTHWEST WINDS...SHIFTING WEST
BEHIND THE SURFACE TROUGH/COLD FRONT...WITH A FEW GUSTS TO 30 MPH.
THE GUSTY SOUTHWEST WINDS PUSH A THERMAL RIDGE AHEAD OF SURFACE
TROUGH OVER THE CWA MIDDAY...WITH BLENDED TEMPERATURES BRINGING
HIGHS IN THE LOWER TO MIDDLE 30S...THOUGH TEMPS COULD BE LOWER IF
FASTER MOVEMENT OF COLD FRONT REFLECTED IN THE GFS AND GEMNH OCCURS.
WEDNESDAY NIGHT AND THURSDAY...FORECAST CONFIDENCE MEDIUM TO HIGH.
WEST-NORTHWEST FLOW BEHIND LOW SHUNTS COLDEST AIR OFF TO THE
NORTHEAST OF THE REGION OVER SOUTHEAST CANADA...BUT ENOUGH COLD AIR
ADVECTION TO BRING SINGLE DIGIT LOWS TO THE NORTH WEDNESDAY
NIGHT...WITH MID-TEENS IN THE SOUTH. HIGH PRESSURE BRINGS QUIET
WEATHER WITH NEUTRAL TEMPERATURE ADVECTION BRINGING HIGHS IN THE
TEENS NORTH TO LOWER 20S SOUTH.
.LONG TERM...THURSDAY NIGHT THROUGH MONDAY. FORECAST CONFIDENCE
LOW TO MEDIUM.
WEAK WAVES PASSING BY TO THE NORTH IN THE NEAR ZONAL FLOW LIFT
850/925MB TEMPERATURES ENOUGH TO WARM HIGHS INTO THE LOWER TO MIDDLE
30S FOR FRIDAY AND SATURDAY. FAR NORTH MAY BE BRUSHED BY LIGHT SNOW
WITH THE WARM ADVECTION PUSH THURSDAY NIGHT...AND ONLY A LITTLE
BETTER CHANCE SATURDAY/SATURDAY NIGHT WITH STRONGER WAVE CROSSING
NORTHERN WISCONSIN. COLD ADVECTION AROUND ARCTIC HIGH SETTLING INTO
THE PLAINS BEHIND THIS LAST WAVE BRINGS HIGHS IN THE TEENS
SUNDAY...WITH SINGLE DIGIT LOWS SUNDAY NIGHT. BLENDED HIGHS ON LY IN
THE SINGLE DIGITS TO LOWER TEENS MONDAY...THEN FALLING TO BELOW
ZERO AWAY FROM LAKE MICHIGAN MONDAY NIGHT. IF COLDER GFS PANS
OUT...READINGS COULD GET EVEN COLDER.
&&
.AVIATION/00Z TAFS/...
STILL WATCHING AN AREA OF MVFR CIGS UPSTREAM. LATEST RAP AND NAM RH
FIELDS INDICATE THIS MAY HOLD TOGETHER AND MOVE INTO THE NORTHWEST
HALF OF THE FORECAST AREA MID TO LATE THIS AFTERNOON. BEST CHANCE
FOR THESE LOWER CIGS APPEARS TO BE ROUGHLY ALONG AND NORTHWEST OF A
MINERAL POINT TO SHEBOYGAN LINE...AS THE HIGH RH IN THE MODELS NEVER
QUITE MAKES IT TO THE SOUTHEAST. WILL CONTINUE TO KEEP AN EYE ON
SATELLITE TRENDS AND MODIFY TAFS AS NEEDED.
ANY LOWER CIGS SHOULD SCATTER OUT OR MOVE OUT BY MORNING...WITH VFR
CONDITIONS THEN EXPECTED THROUGH THE DAY TUESDAY.
&&
.MARINE...
SOUTHWEST WINDS WILL INCREASE TUESDAY NIGHT AHEAD OF AN APPROACHING
TROUGH OF LOW PRESSURE. WIND GUSTS ARE EXPECTED TO PEAK IN THE 30-35
KT RANGE LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING. MODELS
CURRENTLY INDICATING GUSTS RIGHT ON THE VERGE OF GALE
FORCE...ESPECIALLY TOWARD OPEN WATERS...SO WILL GO WITH A GALE WATCH
FOR THIS PERIOD OF HIGHER GUSTS. WILL LIKELY SEE GUSTS TO SMALL
CRAFT LEVELS EARLIER IN THE NIGHT AS THINGS RAMP UP...AND INTO
WEDNESDAY AFTERNOON AS WINDS EASE.
THE HIGHEST WAVES WILL BE ACROSS THE NORTH AND TOWARD OPEN WATERS
DUE TO THE EXPECTED SOUTHWEST FLOW. NOT EXPECTING WAVES WILL GET
PARTICULARLY HIGH GIVEN THE OFFSHORE COMPONENT TO THE WINDS.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...GALE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING FOR
LMZ643>646.
&&
$$
TONIGHT/TUESDAY AND AVIATION/MARINE...DDV
TUESDAY NIGHT THROUGH MONDAY...REM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1128 AM CST MON JAN 14 2013
.SHORT TERM...TODAY THROUGH WEDNESDAY
322 AM CST MON JAN 14 2013
AT 3 AM...A SURFACE TROUGH WAS LOCATED ACROSS SOUTHWEST MINNESOTA.
THIS TROUGH IS CURRENTLY PRODUCING A MVFR DECK OF CLOUDS ACROSS
EASTERN SOUTH DAKOTA AND SOUTHWEST MINNESOTA. THERE ARE EVEN
FLURRIES BEING REPORTED AT SIOUX FALLS SOUTH DAKOTA. FURTHER TO
THE SOUTHWEST...THE WATER VAPOR IMAGERY SHOWS A SHORT WAVE TROUGH
MOVING OUT OF COLORADO. THIS SYSTEM HAS BEEN PRODUCING SOME LIGHT
SNOW FROM COLORADO INTO CENTRAL SOUTH DAKOTA. THE 14.00Z MODELS
ARE IN GOOD AGREEMENT THAT THE SURFACE TROUGH WILL MOVE SLOWLY
EAST AND GRADUALLY WEAKEN TODAY. MEANWHILE THE SHORT WAVE WILL
MOVE ACROSS THE AREA THIS AFTERNOON. BOTH THE GFS AND NAM/WRF
SOUNDINGS SHOW LITTLE OMEGA WITH THESE SYSTEMS. MEANWHILE THE RAP
HAS UP TO 5 MICROBARS OF OMEGA CO-LOCATED WITH THE DENDRITIC
GROWTH ZONE. SINCE BOTH SYSTEMS ARE CURRENTLY PRODUCING SOME
FLURRIES OR VERY LIGHT SNOW...WENT MORE TOWARD THE RAP AND
INTRODUCED SOME SCATTERED FLURRIES FOR THIS AFTERNOON NORTHWEST OF
SAINT ANSGAR IOWA TO WISCONSIN RAPIDS LINE.
ON TUESDAY NIGHT AND WEDNESDAY...THE MODELS CONTINUE TO SHOW THAT
A LOW PRESSURE SYSTEM WILL MOVE ALONG THE ARCTIC COLD FRONT TO OUR
NORTH. AS THE WAVE APPROACHES...THE CLOUDS WILL INCREASE OVERNIGHT
AND TEMPERATURES WILL SLOWLY RISE. LIKE THE PAST COUPLE OF
DAYS...THE MODELS CONTINUE TO SHOW THAT THERE WILL BE ENOUGH
MOISTURE FOR SOME PRECIPITATION TO DEVELOP ALONG AND NORTH OF THE
INTERSTATE 90 CORRIDOR OVERNIGHT TUESDAY AND WEDNESDAY MORNING.
HOWEVER SOUNDINGS CONTINUE TO STRUGGLE ON WHETHER THERE WILL BE
ICE CRYSTAL SEEDING OR NOT. IN MANY CASES...WHERE THEY SHOW THE
LACK OF ICE...THERE IS NO PRECIPITATION. SINCE THERE IS NO CLEAR
SIGNAL...JUST KEPT THE PRECIPITATION IN THE FORM OF SNOW FOR NOW.
HOWEVER A BIT CONCERNED THAT THERE MAY BE SOME LIGHT FREEZING
DRIZZLE ON THE SOUTHERN PERIPHERY OF THE PRECIPITATION.
ANOTHER CONCERN ON WEDNESDAY IS THE TEMPERATURES...THE NAM/WRF HAS
WAY TOO MUCH SNOW COVER IN IT. THIS MODEL SHOWED 1 TO 2 INCHES OF
SNOW ON THE GROUND ACROSS NORTHEAST IOWA AND SOUTHEAST
MINNESOTA...AND 2 TO 5 INCHES OF SNOW ACROSS WESTERN WISCONSIN.
COOPERATIVE REPORTS AND NOHRSC SHOW THAT WITH THE EXCEPTION OF AN
INCH AT MEDFORD WISCONSIN...MUCH OF THE AREA IS SNOW FREE. DUE TO
THIS...THE NAM/WRF TEMPERATURES ARE WAY TOO COLD. TYPICALLY...AT
LA CROSSE THE MID-JANUARY MAXIMUM TEMPERATURES AVERAGE 10 DEGREES
WARMER THAN THE LONG TERM AVERAGE /24.7 DEGREES AT KLSE/ WHEN
THERE IS NO SNOW ON THE GROUND. THIS FITS IN WELL WITH A BLEND OF
THE GFS/ECMWF/GEM. WOULD NOT BE SURPRISED TO SEE SOME LOWER 40S
ACROSS SOUTHWEST WISCONSIN AND NORTHEAST IOWA.
.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
322 AM CST MON JAN 14 2013
ON THURSDAY AND THURSDAY NIGHT...THE 14.00Z MODELS CONTINUE TO
STRUGGLE ON HOW FAR SOUTH THE ARCTIC FRONT WILL GET. THE GFS HAS
THIS FRONT DROPPING SOUTH OF THE FORECAST AREA. MEANWHILE THE
NAM/WRF KEEPS THIS FRONT NORTH OF THE FORECAST AREA. THIS IS DUE
TO ANOTHER LOW PRESSURE SYSTEM QUICKLY FOLLOWING THE LOW THAT
PASSES TO THE NORTH OF THE AREA ON TUESDAY NIGHT AND WEDNESDAY.
MEANWHILE THE ECMWF IS A GOOD COMPROMISE BETWEEN THE TWO AND IT
HAS THIS FRONT ONLY GETTING AS FAR SOUTH AS THE INTERSTATE 94
CORRIDOR. DUE TO THESE DIFFERENCES...THERE IS LOWER THAN USUAL
CONFIDENCE IN THE TEMPERATURES. EVEN THE SNOWFALL FORECAST IS
UNCERTAIN DUE TO THE VARIOUS TIMING OF THE WAVES AND THE PLACEMENT
OF THE FRONT /THE SNOW WILL BE MAINLY CONFINED NORTH OF THIS
FRONT/.
ON FRIDAY...THE MODELS CONTINUE TO SHOW THAT A LOW PRESSURE AREA
WILL BE PASSING NORTH OF THE AREA. THE COMBINATION OF SOUTHWEST
WINDS AND SUNSHINE WILL ALLOW TEMPERATURES TO ONCE AGAIN WARM INTO
THE 30S AND LOWER 40S. THE ECMWF EVEN SUGGESTS LOWER AND MID 40S.
SINCE THIS HAS BEEN A CONSISTENT SIGNAL...RAISED THE ALL BLEND
TEMPERATURES BY ABOUT 5 DEGREES.
ON SUNDAY...THE MODELS CONTINUE TO STRUGGLE ON HOW FAR SOUTH THE
ARCTIC FRONT WILL SAG SOUTHWARD INTO THE AREA. A COUPLE OF DAYS
AGO THE ECMWF CONSISTENTLY SHOWED THAT THIS FRONT WOULD MOVE WELL
SOUTH OF THE AREA. THE 13.12Z ECMWF BACKED AWAY FROM THIS
SOLUTION...AND THE 14.00Z ECMWF HAS RETURNED BACK TO ITS COLDER
SOLUTION. SINCE THERE IS SOME UNCERTAINTY ON WHERE THIS FRONT WILL
BE LOCATED AND CONCERN ABOUT HOW MUCH MODERATION MAY TAKE PLACE
WITH THE LACK OF SNOW ACROSS THE AREA...JUST STAYED WITH THE ALL
BLEND FORECAST FOR NOW.
&&
.AVIATION...THROUGH 18Z TUESDAY
1128 AM CST MON JAN 14 2013
WEAK MID-LEVEL TROUGH WAS PUSHING BROKEN DECK OF VFR/MVFR
STRATOCUMULUS INTO THE AREA LATE THIS MORNING. EXPECT THIS CLOUD TO
LINGER THIS AFTERNOON WITH SCATTERED LIGHT FLURRY ACTIVITY. PLAN
ON THE CLOUDS TO ERODE THIS EVENING WITH LOSS OF SURFACE HEATING
AND INCREASING LOW-LEVEL SUBSIDENCE. VFR CONDITIONS THEN EXPECTED
THROUGH THE OVERNIGHT HOURS AND THROUGH TUESDAY AS SURFACE HIGH
PRESSURE BUILDS OVERHEAD.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
322 AM CST MON JAN 14 2013
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...DAS
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
949 AM CST MON JAN 14 2013
.UPDATE...MOSTLY SUNNY SKIES WILL CONTINUE THROUGH THE MORNING.
COULD SEE SOME HIGH CLOUDS MOVE IN FROM THE SOUTH THIS
AFTERNOON...AND AN AREA OF LOW CLOUDS MAY ALSO MOVE INTO THE
NORTHWEST FORECAST AREA BY LATE AFTERNOON. OTHERWISE...A
QUIET...BUT CHILLY DAY STILL EXPECTED WITH HIGHS A FEW DEGREES
BELOW NORMAL.
&&
.AVIATION/18Z TAFS/...WATCHING AN AREA OF MVFR CIGS UPSTREAM.
LATEST RAP AND NAM RH FIELDS INDICATE THIS MAY HOLD TOGETHER AND
MOVE INTO THE NORTHWEST HALF OF THE FORECAST AREA MID TO LATE THIS
AFTERNOON. BEST CHANCE FOR THESE LOWER CIGS APPEARS TO BE ROUGHLY
ALONG AND NORTHWEST OF A MINERAL POINT TO SHEBOYGAN LINE...AS THE
HIGH RH IN THE MODELS NEVER QUITE MAKES IT TO THE SOUTHEAST. WILL
KEEP AN EYE ON SATELLITE TRENDS AND CONSIDER ADDING SOME LOWER
CIGS TO THE TAFS.
ANY LOWER CIGS SHOULD SCATTER OUT OR MOVE OUT BY MORNING...WITH VFR
CONDITIONS THEN EXPECTED THROUGH THE DAY TUESDAY.
&&
.PREV DISCUSSION... /ISSUED 321 AM CST MON JAN 14 2013/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.
HIGH PRESSURE SLIDING INTO THE AREA WILL BRING QUIET WEATHER TO
REGION. A COLD START TO THE DAY...COUPLED WITH A DECENT THERMAL
TROUGH LINGERING OVER THE WESTERN GREAT LAKES MEANS TEMPS WON/T
RECOVER VERY FAST TODAY. THIS WILL PROBABLY BE THE COLDEST DAY OF
THE WEEK...THOUGH THURSDAY WILL CHALLENGE IT.
SOME LOWER CLOUDS ASSOCIATED WITH WEAK COLD AIR ADVECTION OVER
THE EASTERN DAKOTAS AND MINNESOTA MAY SNEAK INTO THE NORTHWEST CWA
TOWARD EVENING. BUT THIS SHOULDN/T MAKE MUCH HEADWAY BEYOND THAT
BEFORE LIFTING TO THE NORTH OR DIMINISHING AS THE CAA WEAKENS.
ALSO...SOME CIRRUS MAY STREAM IN FROM THE SOUTHWEST TODAY AND
TONIGHT AS A VERY STRONG UPPER LEVEL JET WILL BE CENTERED FROM
OKLAHOMA NORTHEAST INTO LOWER MICHIGAN.
TEMPS TONIGHT WILL BE A LITTLE TRICKY AND VERY DEPENDENT ON THE
THICKNESS OF THE POSSIBLE CLOUDS. THOSE CLOUDS AREN/T A
CERTAINTY...SO PLAYED IT CAUTIOUSLY. ANOTHER COLD NIGHT ON TAP
BEFORE TEMPS RISE INTO THE MIDDLE OF THE WEEK.
TUESDAY THROUGH WEDNESDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM.
SHORT TERM MODELS SHOWING 500MB FLOW WEST SOUTHWEST
TUESDAY...BEFORE A SHORTWAVE TROUGH SLIDES EAST ACROSS THE REGION
LATER TUESDAY AND TUESDAY EVENING. 500MB WINDS GRADUALLY VEER WEST
NORTHWEST BEHIND THE SHORTWAVE TROUGH LATER TUESDAY NIGHT THROUGH
WEDNESDAY NIGHT. GFS/CANADIAN BRING A VORTICITY MAXIMUM INTO
NORTHERN PORTIONS OF THE AREA WEDNESDAY NIGHT...WITH THE NAM WELL
NORTH OF THE AREA WITH THIS FEATURE. THE ECMWF BRINGS THIS FEATURE
IN WEDNESDAY.
AT THE SURFACE...HIGH PRESSURE TO THE SOUTH OF THE AREA TUESDAY
WILL SLIDE TO THE SOUTH SOUTHWEST TUESDAY NIGHT. MEANWHILE...WARM
AIR ADVECTION MOVES INTO THE AREA TUESDAY NIGHT INTO
WEDNESDAY...WITH STRONG LOW PRESSURE PASSING WELL NORTHEAST OF THE
AREA.
MODEST Q VECTOR CONVERGENCE SEEN ACROSS NORTHWESTERN AND NORTHERN
PORTIONS OF THE AREA TUESDAY NIGHT INTO WEDNESDAY...THOUGH MODELS
HAVE DRY TUESDAY NIGHT AND VERY LIGHT/SPOTTY QPF WEDNESDAY
MORNING. AREA FORECAST SOUNDINGS TRY TO MOISTEN UP WEDNESDAY
MORNING. KEPT LOW END POPS FOR WEDNESDAY MORNING IN THE FAR
NORTHERN COUNTIES.
PRESSURE GRADIENT GETS TIGHT TUESDAY NIGHT INTO WEDNESDAY...WHICH
WILL BRING BRISK WEST WINDS. TEMPERATURES WILL MODERATE A BIT
DURING THIS PERIOD.
COLD FRONT SLIDES SOUTHEAST THROUGH THE AREA WEDNESDAY AFTERNOON
AND EVENING...WITH THE ECMWF/CANADIAN QUICKER THAN THE GFS/NAM.
CANADIAN IS MOST AGGRESSIVE MODEL WITH QPF ACROSS THE AREA DURING
THIS TIME...WITH LIGHT QPF IN THE EVENING ON THE GFS...AND THE
NAM/ECMWF DRY.
WEAK TO MODEST UPWARD MOTION SEEN ON 850MB TO 700MB FRONTOGENESIS
RESPONSE FIELDS DURING THIS TIME. KEPT SMALL CHANCES FOR LIGHT
SNOW SHOWERS GOING FOR FAR NORTHERN AND NORTHEASTERN PORTIONS OF
THE AREA FOR THIS TIME. GFS/ECMWF/CANADIAN SHOW STRONG COLD AIR
ADVECTION AFTER THE COLD FRONTAL PASSAGE WEDNESDAY NIGHT...WITH
THE NAM MUCH WARMER. TRENDED TOWARD THE COOLER SOLUTIONS FOR
TEMPERATURES WEDNESDAY NIGHT.
THURSDAY THROUGH SUNDAY...FORECAST CONFIDENCE IS MEDIUM.
ECMWF/GFS SHOW SOME DIFFERENCES DURING THIS PERIOD ACROSS THE
AREA. THEY BOTH DO SHOW WEAK HIGH PRESSURE TO THE WEST KEEPING
QUIET WEATHER ACROSS THE AREA FOR THURSDAY.
ECMWF THEN BRINGS A WARM FRONT ACROSS THE AREA LATE THURSDAY
NIGHT WITH AN AREA OF QPF CLIPPING THE FAR NORTH...EXITING BY
FRIDAY AFTERNOON. IT IS THEN DRY THROUGH SATURDAY ACROSS THE
REGION.
GFS KEEPS THURSDAY NIGHT DRY...WITH THE WARM FRONT THEN SETTING
UP WEST TO EAST ACROSS THE FAR NORTHERN COUNTIES FRIDAY. THIS
KEEPS MOST OF THE QPF JUST NORTH OF THE FORECAST AREA FRIDAY AND
FRIDAY NIGHT. USED CONSENSUS POPS AND TEMPERATURES FOR THURSDAY
THROUGH FRIDAY NIGHT...GIVEN THE DIFFERENCES IN THE MODELS.
THE GFS THEN DEVELOPS LOW PRESSURE OVER NORTHERN LOWER MICHIGAN BY
00Z SUNDAY...WITH A STRONG COLD FRONT PUSHING SOUTHEAST THROUGH
THE AREA. STRONG COLD AIR ADVECTION THEN BRINGS A VERY COLD
AIRMASS INTO THE AREA FOR SATURDAY NIGHT AND SUNDAY.
THE ECMWF DELAYS THIS SYSTEM UNTIL SATURDAY NIGHT. GFS CLIPS THE
NORTHEASTERN HALF OF THE AREA WITH QPF SATURDAY. THE ECMWF DOES
HAVE LIGHT QPF JUST MISSING THE AREA SATURDAY NIGHT WITH A PASSING
VORTICITY MAXIMUM TO THE NORTH. AGAIN...USED CONSENSUS POPS AND
TEMPERATURES FOR THIS PERIOD WITH THE UNCERTAINTY IN THE MODELS.
AVIATION/12Z TAFS/...HIGH PRESSURE WILL BRING VFR CONDITIONS TO
THE AREA THROUGH THE TAF PERIOD. JUST SOME HIGH CLOUDS MOSTLY.
MARINE...A STRONG LOW PRESSURE SYSTEM PASSING JUST NORTH OF THE
U.S./CANADIAN BORDER LATE TUESDAY NIGHT THROUGH WEDNESDAY WILL
LIKELY RESULT IN SMALL CRAFT ADVISORY CONDITIONS DURING THIS
PERIOD. EXPECT BRISK SOUTHWEST WINDS OF 15 TO 25 KNOTS VEERING
WEST WITH TIME. A FEW GALE GUSTS TO 35 KNOTS WILL BE POSSIBLE.
WAVES OF 3 TO 6 FEET ARE LIKELY...WITH THE HIGHEST WAVES TOWARD
OPEN WATER.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...DDV
TODAY/TONIGHT AND AVIATION/MARINE...DAVIS
TUESDAY THROUGH SUNDAY...WOOD
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
516 AM CST MON JAN 14 2013
.SHORT TERM...TODAY THROUGH WEDNESDAY
322 AM CST MON JAN 14 2013
AT 3 AM...A SURFACE TROUGH WAS LOCATED ACROSS SOUTHWEST MINNESOTA.
THIS TROUGH IS CURRENTLY PRODUCING A MVFR DECK OF CLOUDS ACROSS
EASTERN SOUTH DAKOTA AND SOUTHWEST MINNESOTA. THERE ARE EVEN
FLURRIES BEING REPORTED AT SIOUX FALLS SOUTH DAKOTA. FURTHER TO
THE SOUTHWEST...THE WATER VAPOR IMAGERY SHOWS A SHORT WAVE TROUGH
MOVING OUT OF COLORADO. THIS SYSTEM HAS BEEN PRODUCING SOME LIGHT
SNOW FROM COLORADO INTO CENTRAL SOUTH DAKOTA. THE 14.00Z MODELS
ARE IN GOOD AGREEMENT THAT THE SURFACE TROUGH WILL MOVE SLOWLY
EAST AND GRADUALLY WEAKEN TODAY. MEANWHILE THE SHORT WAVE WILL
MOVE ACROSS THE AREA THIS AFTERNOON. BOTH THE GFS AND NAM/WRF
SOUNDINGS SHOW LITTLE OMEGA WITH THESE SYSTEMS. MEANWHILE THE RAP
HAS UP TO 5 MICROBARS OF OMEGA CO-LOCATED WITH THE DENDRITIC
GROWTH ZONE. SINCE BOTH SYSTEMS ARE CURRENTLY PRODUCING SOME
FLURRIES OR VERY LIGHT SNOW...WENT MORE TOWARD THE RAP AND
INTRODUCED SOME SCATTERED FLURRIES FOR THIS AFTERNOON NORTHWEST OF
SAINT ANSGAR IOWA TO WISCONSIN RAPIDS LINE.
ON TUESDAY NIGHT AND WEDNESDAY...THE MODELS CONTINUE TO SHOW THAT
A LOW PRESSURE SYSTEM WILL MOVE ALONG THE ARCTIC COLD FRONT TO OUR
NORTH. AS THE WAVE APPROACHES...THE CLOUDS WILL INCREASE OVERNIGHT
AND TEMPERATURES WILL SLOWLY RISE. LIKE THE PAST COUPLE OF
DAYS...THE MODELS CONTINUE TO SHOW THAT THERE WILL BE ENOUGH
MOISTURE FOR SOME PRECIPITATION TO DEVELOP ALONG AND NORTH OF THE
INTERSTATE 90 CORRIDOR OVERNIGHT TUESDAY AND WEDNESDAY MORNING.
HOWEVER SOUNDINGS CONTINUE TO STRUGGLE ON WHETHER THERE WILL BE
ICE CRYSTAL SEEDING OR NOT. IN MANY CASES...WHERE THEY SHOW THE
LACK OF ICE...THERE IS NO PRECIPITATION. SINCE THERE IS NO CLEAR
SIGNAL...JUST KEPT THE PRECIPITATION IN THE FORM OF SNOW FOR NOW.
HOWEVER A BIT CONCERNED THAT THERE MAY BE SOME LIGHT FREEZING
DRIZZLE ON THE SOUTHERN PERIPHERY OF THE PRECIPITATION.
ANOTHER CONCERN ON WEDNESDAY IS THE TEMPERATURES...THE NAM/WRF HAS
WAY TOO MUCH SNOW COVER IN IT. THIS MODEL SHOWED 1 TO 2 INCHES OF
SNOW ON THE GROUND ACROSS NORTHEAST IOWA AND SOUTHEAST
MINNESOTA...AND 2 TO 5 INCHES OF SNOW ACROSS WESTERN WISCONSIN.
COOPERATIVE REPORTS AND NOHRSC SHOW THAT WITH THE EXCEPTION OF AN
INCH AT MEDFORD WISCONSIN...MUCH OF THE AREA IS SNOW FREE. DUE TO
THIS...THE NAM/WRF TEMPERATURES ARE WAY TOO COLD. TYPICALLY...AT
LA CROSSE THE MID-JANUARY MAXIMUM TEMPERATURES AVERAGE 10 DEGREES
WARMER THAN THE LONG TERM AVERAGE /24.7 DEGREES AT KLSE/ WHEN
THERE IS NO SNOW ON THE GROUND. THIS FITS IN WELL WITH A BLEND OF
THE GFS/ECMWF/GEM. WOULD NOT BE SURPRISED TO SEE SOME LOWER 40S
ACROSS SOUTHWEST WISCONSIN AND NORTHEAST IOWA.
.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
322 AM CST MON JAN 14 2013
ON THURSDAY AND THURSDAY NIGHT...THE 14.00Z MODELS CONTINUE TO
STRUGGLE ON HOW FAR SOUTH THE ARCTIC FRONT WILL GET. THE GFS HAS
THIS FRONT DROPPING SOUTH OF THE FORECAST AREA. MEANWHILE THE
NAM/WRF KEEPS THIS FRONT NORTH OF THE FORECAST AREA. THIS IS DUE
TO ANOTHER LOW PRESSURE SYSTEM QUICKLY FOLLOWING THE LOW THAT
PASSES TO THE NORTH OF THE AREA ON TUESDAY NIGHT AND WEDNESDAY.
MEANWHILE THE ECMWF IS A GOOD COMPROMISE BETWEEN THE TWO AND IT
HAS THIS FRONT ONLY GETTING AS FAR SOUTH AS THE INTERSTATE 94
CORRIDOR. DUE TO THESE DIFFERENCES...THERE IS LOWER THAN USUAL
CONFIDENCE IN THE TEMPERATURES. EVEN THE SNOWFALL FORECAST IS
UNCERTAIN DUE TO THE VARIOUS TIMING OF THE WAVES AND THE PLACEMENT
OF THE FRONT /THE SNOW WILL BE MAINLY CONFINED NORTH OF THIS
FRONT/.
ON FRIDAY...THE MODELS CONTINUE TO SHOW THAT A LOW PRESSURE AREA
WILL BE PASSING NORTH OF THE AREA. THE COMBINATION OF SOUTHWEST
WINDS AND SUNSHINE WILL ALLOW TEMPERATURES TO ONCE AGAIN WARM INTO
THE 30S AND LOWER 40S. THE ECMWF EVEN SUGGESTS LOWER AND MID 40S.
SINCE THIS HAS BEEN A CONSISTENT SIGNAL...RAISED THE ALL BLEND
TEMPERATURES BY ABOUT 5 DEGREES.
ON SUNDAY...THE MODELS CONTINUE TO STRUGGLE ON HOW FAR SOUTH THE
ARCTIC FRONT WILL SAG SOUTHWARD INTO THE AREA. A COUPLE OF DAYS
AGO THE ECMWF CONSISTENTLY SHOWED THAT THIS FRONT WOULD MOVE WELL
SOUTH OF THE AREA. THE 13.12Z ECMWF BACKED AWAY FROM THIS
SOLUTION...AND THE 14.00Z ECMWF HAS RETURNED BACK TO ITS COLDER
SOLUTION. SINCE THERE IS SOME UNCERTAINTY ON WHERE THIS FRONT WILL
BE LOCATED AND CONCERN ABOUT HOW MUCH MODERATION MAY TAKE PLACE
WITH THE LACK OF SNOW ACROSS THE AREA...JUST STAYED WITH THE ALL
BLEND FORECAST FOR NOW.
&&
.AVIATION...TODAY AND TONIGHT
515 AM CST MON JAN 14 2013
FOG PRODUCT OFF THE IR SATELLITE IS SHOWING A PATCH OF MVFR CLOUDS
MOVING EAST ACROSS SOUTHERN MINNESOTA. TIMING THESE CLOUDS OFF THE
SATELLITE...IT LOOKS LIKE THEY SHOULD BE INTO KRST AROUND 12Z AND
BY MID MORNING FOR KLSE. THEY SHOULD THEN LAST ABOUT 6 HOURS
BEFORE MOVING OFF TO THE EAST. AS WITH THE PAST FEW DAYS...SOME
FLURRIES WILL LIKELY OCCUR WITH THE CLOUDS BUT NO VISIBILITY
RESTRICTIONS ARE EXPECTED. A FEW CLOUDS MAY LINGER THROUGH THE
AFTERNOON BEHIND THE MAIN PATCH OF CLOUDS...BUT BY EVENING AND FOR
THE OVERNIGHT HOURS...THE 14.06Z NAM BUFKIT SOUNDING INDICATE
SKIES SHOULD BE CLEAR WITH VFR CONDITIONS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
322 AM CST MON JAN 14 2013
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
323 AM CST MON JAN 14 2013
.SHORT TERM...TODAY THROUGH WEDNESDAY
322 AM CST MON JAN 14 2013
AT 3 AM...A SURFACE TROUGH WAS LOCATED ACROSS SOUTHWEST MINNESOTA.
THIS TROUGH IS CURRENTLY PRODUCING A MVFR DECK OF CLOUDS ACROSS
EASTERN SOUTH DAKOTA AND SOUTHWEST MINNESOTA. THERE ARE EVEN
FLURRIES BEING REPORTED AT SIOUX FALLS SOUTH DAKOTA. FURTHER TO
THE SOUTHWEST...THE WATER VAPOR IMAGERY SHOWS A SHORT WAVE TROUGH
MOVING OUT OF COLORADO. THIS SYSTEM HAS BEEN PRODUCING SOME LIGHT
SNOW FROM COLORADO INTO CENTRAL SOUTH DAKOTA. THE 14.00Z MODELS
ARE IN GOOD AGREEMENT THAT THE SURFACE TROUGH WILL MOVE SLOWLY
EAST AND GRADUALLY WEAKEN TODAY. MEANWHILE THE SHORT WAVE WILL
MOVE ACROSS THE AREA THIS AFTERNOON. BOTH THE GFS AND NAM/WRF
SOUNDINGS SHOW LITTLE OMEGA WITH THESE SYSTEMS. MEANWHILE THE RAP
HAS UP TO 5 MICROBARS OF OMEGA CO-LOCATED WITH THE DENDRITIC
GROWTH ZONE. SINCE BOTH SYSTEMS ARE CURRENTLY PRODUCING SOME
FLURRIES OR VERY LIGHT SNOW...WENT MORE TOWARD THE RAP AND
INTRODUCED SOME SCATTERED FLURRIES FOR THIS AFTERNOON NORTHWEST OF
SAINT ANSGAR IOWA TO WISCONSIN RAPIDS LINE.
ON TUESDAY NIGHT AND WEDNESDAY...THE MODELS CONTINUE TO SHOW THAT
A LOW PRESSURE SYSTEM WILL MOVE ALONG THE ARCTIC COLD FRONT TO OUR
NORTH. AS THE WAVE APPROACHES...THE CLOUDS WILL INCREASE OVERNIGHT
AND TEMPERATURES WILL SLOWLY RISE. LIKE THE PAST COUPLE OF
DAYS...THE MODELS CONTINUE TO SHOW THAT THERE WILL BE ENOUGH
MOISTURE FOR SOME PRECIPITATION TO DEVELOP ALONG AND NORTH OF THE
INTERSTATE 90 CORRIDOR OVERNIGHT TUESDAY AND WEDNESDAY MORNING.
HOWEVER SOUNDINGS CONTINUE TO STRUGGLE ON WHETHER THERE WILL BE
ICE CRYSTAL SEEDING OR NOT. IN MANY CASES...WHERE THEY SHOW THE
LACK OF ICE...THERE IS NO PRECIPITATION. SINCE THERE IS NO CLEAR
SIGNAL...JUST KEPT THE PRECIPITATION IN THE FORM OF SNOW FOR NOW.
HOWEVER A BIT CONCERNED THAT THERE MAY BE SOME LIGHT FREEZING
DRIZZLE ON THE SOUTHERN PERIPHERY OF THE PRECIPITATION.
ANOTHER CONCERN ON WEDNESDAY IS THE TEMPERATURES...THE NAM/WRF HAS
WAY TOO MUCH SNOW COVER IN IT. THIS MODEL SHOWED 1 TO 2 INCHES OF
SNOW ON THE GROUND ACROSS NORTHEAST IOWA AND SOUTHEAST
MINNESOTA...AND 2 TO 5 INCHES OF SNOW ACROSS WESTERN WISCONSIN.
COOPERATIVE REPORTS AND NOHRSC SHOW THAT WITH THE EXCEPTION OF AN
INCH AT MEDFORD WISCONSIN...MUCH OF THE AREA IS SNOW FREE. DUE TO
THIS...THE NAM/WRF TEMPERATURES ARE WAY TOO COLD. TYPICALLY...AT
LA CROSSE THE MID-JANUARY MAXIMUM TEMPERATURES AVERAGE 10 DEGREES
WARMER THAN THE LONG TERM AVERAGE /24.7 DEGREES AT KLSE/ WHEN
THERE IS NO SNOW ON THE GROUND. THIS FITS IN WELL WITH A BLEND OF
THE GFS/ECMWF/GEM. WOULD NOT BE SURPRISED TO SEE SOME LOWER 40S
ACROSS SOUTHWEST WISCONSIN AND NORTHEAST IOWA.
.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
322 AM CST MON JAN 14 2013
ON THURSDAY AND THURSDAY NIGHT...THE 14.00Z MODELS CONTINUE TO
STRUGGLE ON HOW FAR SOUTH THE ARCTIC FRONT WILL GET. THE GFS HAS
THIS FRONT DROPPING SOUTH OF THE FORECAST AREA. MEANWHILE THE
NAM/WRF KEEPS THIS FRONT NORTH OF THE FORECAST AREA. THIS IS DUE
TO ANOTHER LOW PRESSURE SYSTEM QUICKLY FOLLOWING THE LOW THAT
PASSES TO THE NORTH OF THE AREA ON TUESDAY NIGHT AND WEDNESDAY.
MEANWHILE THE ECWMF IS A GOOD COMPROMISE BETWEEN THE TWO AND IT
HAS THIS FRONT ONLY GETTING AS FAR SOUTH AS THE INTERSTATE 94
CORRIDOR. DUE TO THESE DIFFERENCES...THERE IS LOWER THAN USUAL
CONFIDENCE IN THE TEMPERATURES. EVEN THE SNOWFALL FORECAST IS
UNCERTAIN DUE TO THE VARIOUS TIMING OF THE WAVES AND THE PLACEMENT
OF THE FRONT /THE SNOW WILL BE MAINLY CONFINED NORTH OF THIS
FRONT/.
ON FRIDAY...THE MODELS CONTINUE TO SHOW THAT A LOW PRESSURE AREA
WILL BE PASSING NORTH OF THE AREA. THE COMBINATION OF SOUTHWEST
WINDS AND SUNSHINE WILL ALLOW TEMPERATURES TO ONCE AGAIN WARM INTO
THE 30S AND LOWER 40S. THE ECMWF EVEN SUGGESTS LOWER AND MID 40S.
SINCE THIS HAS BEEN A CONSISTENT SIGNAL...RAISED THE ALL BLEND
TEMPERATURES BY ABOUT 5 DEGREES.
ON SUNDAY...THE MODELS CONTINUE TO STRUGGLE ON HOW FAR SOUTH THE
ARCTIC FRONT WILL SAG SOUTHWARD INTO THE AREA. A COUPLE OF DAYS
AGO THE ECMWF CONSISTENTLY SHOWED THAT THIS FRONT WOULD MOVE WELL
SOUTH OF THE AREA. THE 13.12Z ECMWF BACKED AWAY FROM THIS
SOLUTION...AND THE 14.00Z ECMWF HAS RETURNED BACK TO ITS COLDER
SOLUTION. SINCE THERE IS SOME UNCERTAINTY ON WHERE THIS FRONT WILL
BE LOCATED AND CONCERN ABOUT HOW MUCH MODERATION MAY TAKE PLACE
WITH THE LACK OF SNOW ACROSS THE AREA...JUST STAYED WITH THE ALL
BLEND FORECAST FOR NOW.
&&
.AVIATION...THROUGH 06Z TUESDAY
1136 PM CST SUN JAN 13 2013
SKIES HAVE CLEARED OUT AT BOTH TAF SITES DUE TO A WEAK RIDGE OF
HIGH PRESSURE THAT HAS MOVED IN. TO THE WEST...A TROUGH OF LOW
PRESSURE WAS MOVING INTO WESTERN MINNESOTA. ACCOMPANYING THE
TROUGH IS A BATCH OF MVFR STRATUS CROSSING FAR EASTERN SOUTH
DAKOTA. MODELS ARE IN GOOD AGREEMENT BRINGING THIS STRATUS INTO
KRST AROUND 16Z AND KLSE AROUND 18Z...THEN LASTING FOR 6-8 HOURS
BEFORE DRIER AIR MOVES BACK IN TO SCOUR THE CLOUDS OUT. GIVEN THAT
THERE WERE FLURRIES WITH THIS STRATUS DURING DAYTIME HEATING
YESTERDAY...HAVE MAINTAINED FLURRY POTENTIAL IN THE TAF. LOOK FOR
WINDS TO HOLD FAIRLY STEADY THROUGH 06Z TUESDAY...OUT OF THE
SOUTHWEST TO WEST AT 5-10 KT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
322 AM CST MON JAN 14 2013
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1008 PM MST TUE JAN 15 2013
.AVIATION...
VFR CONDITIONS EXPECTED AT ALL THREE TERMINALS THROUGH THE NEXT 24
HOURS. THE ONLY UNCERTAINTY FOR TONIGHT WILL BE WHETHER OR NOT FOG
OR STRATUS DEVELOP AT KALS LATE TONIGHT. GIVEN PERIODS OF MID TO
HIGH LEVEL CLOUD COVER ACROSS THE REGION...HAVE LEFT MENTION OF
FOG/STRATUS OUT OF THE FORECAST FOR NOW. MOZLEY
&&
.PREV DISCUSSION... /ISSUED 802 PM MST TUE JAN 15 2013/
UPDATE...
QUICK UPDATE TO BACK OFF POPS ACROSS THE NM/CO BORDER THROUGH 12Z
IN COORD WITH ABQ...AS LATEST RAP AND NAM12 SHOW ZERO QPF IN THOSE
AREAS IN THE SHORT TERM. -PJC
PREV DISCUSSION... /ISSUED 320 PM MST TUE JAN 15 2013/
SHORT TERM...
(TONIGHT AND WEDNESDAY)
.WARMER WEATHER IS ON THE WAY...
NICE RECOVERY ACROSS THE PLAINS TODAY...DESPITE A HIGH BKN CLOUD DECK
FROM AN APPROACHING SHORTWAVE. TEMPS RIGHT AROUND FREEZING AS OF MID
AFTERNOON...WHILE MTS AND HIGH VALLEYS GENERALLY REMAIN IN THE SINGLE
DIGITS TO TEENS.
NOT MUCH SHOWING UP ON WSR RIGHT NOW...BUT UPSTREAM OBS OVER NRN COL
AND SRN WY SHOW CIGS DROPPING TO THE 030-040 RANGE...AND EXPECT THE
TREND IN THICKER CLOUD COVER TO CONTINUE THROUGH THIS AFTERNOON AND
INTO THIS EVE. 18Z NAM HAS REALLY BACKED OFF QPF OVER OUR AREA...BUT
STILL EXPECT SOME ISOLD-SCT LIGHT SHSN OVER THE MTS AND PORTIONS OF
TELLER AND NRN EL PASO COUNTIES THIS EVE. VERY LITTLE IF ANY
ACCUMULATION EXPECTED. MAIN IMPACT OF THIS DISTURBANCE WILL BE
THICKER CLOUD COVER...RESULTING IN MILDER OVERNIGHT TEMPS ESPECIALLY
OVER THE PLAINS...AND A PERIOD OF GUSTY WINDS OVER THE PLAINS LATE
TONIGHT AND EARLY WED MORNING. N SIDE OF PIKES PEAK AND PORTIONS OF
TELLER COUNTY AND THE PALMER DVD...ALONG WITH THE WETS AND
SANGRES...WILL SEE THE MOST WIND...AS H7 WINDS FROM 40-50 KTS SWEEP
OVER THE ERN PLAINS TONIGHT.
WED LOOKS COMPLETELY DRY...WITH PLENTY OF SUN FOR THE AFTERNOON. THE
CENTRAL MTS COULD SEE SOME LINGERING CLOUDS THROUGH THE DAY...BUT NO
PRECIP EXPECTED AS AN UPPER RIDGE BUILDS RAPIDLY FROM THE W. IT WILL
BE QUITE MILD FOR THE PLAINS...WITH TEMPS LIKELY IN THE
50S...POSSIBLY NEARING 60 IF THE WINDS ARE A BIT STRONGER FROM THE W.
MTS AND HIGHER ELEVS WEST WILL STILL BE CHILLY...BUT COMPARATIVELY
BALMY AFTER THIS RECENT COLD SNAP...WITH TEMPS LARGELY IN THE 20S.
44
LONG TERM...
(WEDNESDAY NIGHT THROUGH NEXT TUESDAY)
MAINLY A TEMPERATURE FORECAST THE NEXT SEVERAL DAYS AS UPPER RIDGE
REMAINS IN PLACE OVER THE WESTERN U.S. THROUGH AT LEAST THE
MIDDLE OF NEXT WEEK...LEADING TO A DRY FORECAST FOR ALL OF THE
AREA AS WEATHER SYSTEMS ARE SHUNTED WELL NORTHEAST OF THE STATE.
A WEAK WAVE MOVING THROUGH THE RIDGE THU WILL PRODUCE ONLY A FEW
CLOUDS ACROSS THE REGION...THOUGH IT MAY SERVE TO SLOW THE WARM-UP
FOR A DAY...ESPECIALLY OVER THE PLAINS. TEMPS BEGIN TO WARM AGAIN
ON FRI INTO SAT...THEN A WEAK COLD FRONT BACKS INTO THE AT LEAST
THE FAR SOUTHEAST PLAINS SUNDAY...COOLING MAX TEMPS A FEW DEGREES
ALONG AND EAST OF THE MOUNTAINS. UNFORTUNATELY...UPPER RIDING WILL
KEEP COLD...STAGNANT AIR MASS IN PLACE OVER THE SAN LUIS
VALLEY...LEADING TO A MUCH SLOWER WARMING TREND HERE THAN
EVERYWHERE ELSE IN THE REGION. STILL...EXPECT DAYTIME HIGHS AT
ALAMOSA TO CLIMB BACK INTO AT LEAST THE 20S BY THE WEEKEND...AND
OVERNIGHT LOWS WILL IMPROVE INTO MAINLY THE TEENS BELOW ZERO
VERSUS THE MINUS 30F READINGS WE`VE SEEN EARLIER THIS WEEK.
WESTWARD EXTENT OF ARCTIC AIR BECOMES THE CONCERN SUNDAY NIGHT
INTO MONDAY...AS STRONG HIGH PRESSURE DROPS SOUTH INTO THE CENTRAL
PLAINS BEHIND DEEP UPPER TROUGH OVER THE GREAT LAKES. GFS SUGGESTS
ANY COLD AIR OVER THE PLAINS WILL BE VERY SHALLOW AND ERODE BY MON
AFTERNOON AS W-NW SURFACE FLOW AND LEE TROUGH DEVELOP. ECMWF IS
MUCH COLDER...KEEPING THE COLD AIR PINNED AGAINST THE EASTERN
MOUNTAINS UNTIL MONDAY NIGHT...BEFORE WARMER AIR SURGES BACK EAST
TUES. FORECAST LEANS TOWARD THE ECMWF AT THIS POINT AS PROGGED
1047 MB SURFACE HIGH OVER WRN NEB MON AFTERNOON SUGGESTS COLD AIR
WILL BE FAIRLY DEEP AND DIFFICULT TO QUICKLY DISLODGE. WENT WELL
BELOW NUMERICAL MOS GUIDANCE AND SLIGHTLY BELOW MODEL CONSENSUS
TEMPS FOR TUE AFTERNOON...ESPECIALLY NEAR THE KS BORDER. TEMPS
BEGIN TO MODERATE ON TUES AS SURFACE RIDGE MOVES EAST AND LEE
TROUGH REFORMS OVER THE EASTERN PLAINS. --10
AVIATION...MAIN CONCERN WILL BE POTENTIAL FOR SHSN NR KCOS THIS
EVE...ALTHOUGH LATEST COMPUTER GUIDANCE SUGGESTS THAT MOST OF EL
PASO SHOULD STAY DRY TONIGHT. COULD STILL SEE A BRIEF PERIOD OF
MVFR CIGS. WINDS ALSO LOOK TO GET A BIT GUSTY LATE TONIGHT INTO
WED MORNING FROM THE NNW...WITH GUSTS TO 30 KTS OR SO OVER THE HYR
TRRN IN THE PIKES PEAK REGION...POSSIBLY REACHING THE KCOS
TERMINAL AT TIMES. CLEAR AND DRY WX IS EXPECTED FOR ALL SPOTS ON
WED. KALS COULD STILL SEE A BRIEF INTERVAL OF LOW CIGS OR SHALLOW
PC FG EARLY ON WED...BUT CONFIDENCE IN ANY WIDESPREAD RESTRICTION
TO VIS IS TOO LOW TO INCLUDE IN THE ALS TAF. 44
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
88/34
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
338 AM EST WED JAN 16 2013
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 212 PM EST TUE JAN 15 2013
QUIET WEATHER CAN BE EXPECTED UNDER HIGH PRESSURE THROUGH THE END
OF THE WEEK WITH TEMPERATURES NEAR NORMAL FOR THIS TIME OF YEAR.
COULD SEE A BRIEF WARM UP SATURDAY INTO THE 40S BEFORE
TEMPERATURES DROP BACK TO NORMAL SUNDAY AND THEN GET VERY COLD TO
START OUT THE WEEK. A CLIPPER SYSTEM WILL MOVE THROUGH SUNDAY
NIGHT THROUGH MONDAY NIGHT BRINGING CHANCES FOR SNOW.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 929 PM EST TUE JAN 15 2013
LATEST SHORT TERM MODEL GUIDANCE ALONG WITH REGIONAL RADAR LOOPS
SUGGEST PRECIPITATION SHIELD ASSOCIATED WITH SYSTEM MOVING THROUGH
THE TENNESSEE VALLEY SHOULD STAY SOUTH OF THE FORECAST AREA TONIGHT
FOR THE MOST PART. ONLY HAVE SLIGHT CHANCE POPS GOING OVER THE FAR
SOUTHEAST FOR THE REST OF THE NIGHT...SO WILL LEAVE THE POP FORECAST
AS IS.
THIS EVENING/S UPPER AIR INDICATE TEMPERATURES NEAR OR BELOW
FREEZING THROUGHOUT THE COLUMN THIS FAR NORTH...SO THINK THE CHANCES
OF FREEZING RAIN THIS FAR NORTH ARE DIMINISHING.
FINALLY...WITH ONLY WEAK COLD ADVECTION TONIGHT AND SKIES REMAINING
CLOUDY MOST OF THE NIGHT...DECIDED TO BUMP UP THE LOWS A COUPLE OF
DEGREES.
PREVIOUS DISCUSSION FOLLOWS.
SKIES SHOULD START OUT MOSTLY CLOUDY WITH A LOW PRESSURE SYSTEM
MOVING NORTHEAST OUT OF THE GULF AND THROUGH THE SOUTHEASTERN U.S. A
BIT OF MODEL DISAGREEMENT OVER HOW FAR NORTH PRECIPITATION
ASSOCIATED WITH THIS SYSTEM WILL GET DESPITE SIMILAR POSITIONS AND
STRENGTH FOR THE LOW PRESSURE CENTER. THE RAP AND GEM WERE THE
FURTHEST NORTH AND BRING THE PRECIP INTO THE FAR SOUTHEASTERN
COUNTIES. THE GFS KEEPS THE PRECIP WELL TO THE SOUTH...WHILE THE NAM
AND 0Z ECMWF JUST CLIP THE FAR SOUTHEAST WITH A HUNDREDTH OF QPF.
WITH THE VARIETY OF SOLUTIONS SHOULD CARRY A LOW CHANCE POP IN THE
FAR SOUTHEAST WITH DRY WEATHER BUT MOSTLY CLOUDY SKIES ELSEWHERE.
WENT WITH LOWS A DEGREE OR TWO BELOW GUIDANCE WITH EXPECTED COLD
ADVECTION.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
ISSUED AT 212 PM EST TUE JAN 15 2013
HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH THE SHORT TERM. A
LOW PRESSURE SYSTEM MOVING ACROSS THE HUDSON BAY WILL DRAG A COLD
FRONT ACROSS THE GREAT LAKES WEDNESDAY AND WEDNESDAY NIGHT...BUT IT
LOOKS LIKE ALL THE FORCING ASSOCIATED WITH IT WILL STAY WELL NORTH
OF THE AREA. ANOTHER SOUTHERN LOW PRESSURE SYSTEM WHICH WILL MOVE
ACROSS THE SOUTHEAST U.S. DURING THE SAME TIME APPEARS TO BE TOO FAR
SOUTH TO IMPACT POPS HERE. GUIDANCE IS IN GOOD AGREEMENT AND WILL
USE AN AVERAGE WHICH RESULTS IN NEAR NORMAL TEMPERATURES AND DRY
WEATHER.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
ISSUED AT 338 AM EST WED JAN 16 2013
MAIN FOCUS CONTINUES TO BE ON TIMING AND MAGNITUDE OF ARCTIC FRONT
SET TO SETTLE SOUTHEAST ACROSS CENTRAL INDIANA EARLY NEXT WEEK.
OPERATIONAL MODELS ARE NOW IN MUCH CLOSER AGREEMENT ON TIMING OF
WESTERN LOBE OF NORTHERN ONTARIO VORTEX ACROSS CENTRAL INDIANA.
HOWEVER...THE 00Z GFS WAS STILL A BIT FASTER TO BRING IN THE ARTIC
FRONT JUDGED BY 1000-500 MILLIBAR THICKNESS FIELDS THAT BRING A 5040
METER LINE TO NORTHERN PARTS OF THE FORECAST AREA BY 00Z TUESDAY.
MEANWHILE...THE 00Z ECMWF WAS EVEN COLDER...5010 METERS...BUT 6
HOURS BEHIND BY 06Z TUESDAY. WITH OPERATIONAL MODELS TRENDING
TOWARDS THE ENSEMBLES...ENSEMBLES ARE PREFERED. HOWEVER...THE BETTER
DEFINED ARCTIC FRONT PER THE OPERATIONAL 00Z ECMWF AND GEM LOOKS A
BIT BETTER THAN THE 00Z GFS. THE REGIONAL INITIALIZATION APPEARS TO
BE EVEN A BIT SLOWER THAN THE SLOWER EURO AND GEM REGARDING THE
LOWEST THICKNESSES WITH THE ARCTIC AIRMASS. SO...LOWERED REGIONAL
HIGHS A COUPLE OF DEGREES ON MONDAY. AT ANY RATE...SATURDAY WILL BE
THE WARMEST DAY OF THE EXTENDED WITH SOUTHWEST FLOW AHEAD OF AN
INITIAL COLD FRONT THAT IS EXPECTED TO SURGE SOUTHEAST ACROSS
CENTRAL INDIANA LATE SATURDAY AND SATURDAY NIGHT. THIS FRONT WILL BE
MOISTURE STARVED...AND THUS DRY FORECAST LOOKS GOOD. THE FRONT WILL
SERVE TO BRING COLDER AIR IN TO CENTRAL INDIANA WITH HIGHS SATURDAY
IN THE 40S BUT ONLY IN THE UPPER 20S TO MID 30S SUNDAY PER THE
REGIONAL INITIALIZATION.
THE SLOWER AND BETTER DEFINED LEADING EDGE OF THE ARCTIC FRONT PER
THE 00Z EURO AND GEM LOOKS TO ARRIVE BY MONDAY MORNING BY 12Z. KEPT
SMALL SNOW CHANCES IN PER THE REGIONAL AND PERSISTANCE...BUT LIMITED
MOISTURE SUGGESTS LITTLE TO NO ACCUMULATION. WITH ARCTIC AIR
ENTRENCHED MONDAY NIGHT...SINGLE DIGIT LOWS LOOK GOOD WITH
TEMPERATURES WARMING NO HIGHER THAN THE TEENS ON TUESDAY.
&&
.AVIATION /DISCUSSION FOR 160600Z TAF ISSUANCE/...
ISSUED AT 1125 PM EST TUE JAN 15 2013
VFR CONDITIONS ANTICIPATED THROUGHOUT THE FORECAST PERIOD. LOW
PRESSURE SHIFTS INTO THE SOUTHERN APPALACHIANS LATE
TONIGHT...MOISTURE ALOFT WILL ALSO BEGIN TO DEPART OFF TO THE EAST
AND CEILINGS ARE EXPECTED TO LIFT AND SCATTER IN THE HOURS
APPROACHING DAYBREAK. HIGH PRESSURE RIDGE THEN BUILDS INTO THE
REGION TODAY WITH BROAD SUBSIDENCE. WILL SEE SKIES BECOME
MOSTLY CLEAR. LIGHT AND VARIABLE WINDS LATE TONIGHT WILL SHIFT TO
W/SW AND INCREASE TO NEAR 10KTS BY THIS AFTERNOON.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP/JAS
SHORT TERM...CP
LONG TERM....MK
AVIATION...SMF
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1123 PM EST TUE JAN 15 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 212 PM EST TUE JAN 15 2013
QUIET WEATHER CAN BE EXPECTED UNDER HIGH PRESSURE THROUGH THE END
OF THE WEEK WITH TEMPERATURES NEAR NORMAL FOR THIS TIME OF YEAR.
COULD SEE A BRIEF WARM UP SATURDAY INTO THE 40S BEFORE
TEMPERATURES DROP BACK TO NORMAL SUNDAY AND THEN GET VERY COLD TO
START OUT THE WEEK. A CLIPPER SYSTEM WILL MOVE THROUGH SUNDAY
NIGHT THROUGH MONDAY NIGHT BRINGING CHANCES FOR SNOW.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 929 PM EST TUE JAN 15 2013
LATEST SHORT TERM MODEL GUIDANCE ALONG WITH REGIONAL RADAR LOOPS
SUGGEST PRECIPITATION SHIELD ASSOCIATED WITH SYSTEM MOVING THROUGH
THE TENNESSEE VALLEY SHOULD STAY SOUTH OF THE FORECAST AREA TONIGHT
FOR THE MOST PART. ONLY HAVE SLIGHT CHANCE POPS GOING OVER THE FAR
SOUTHEAST FOR THE REST OF THE NIGHT...SO WILL LEAVE THE POP FORECAST
AS IS.
THIS EVENING/S UPPER AIR INDICATE TEMPERATURES NEAR OR BELOW
FREEZING THROUGHOUT THE COLUMN THIS FAR NORTH...SO THINK THE CHANCES
OF FREEZING RAIN THIS FAR NORTH ARE DIMINISHING.
FINALLY...WITH ONLY WEAK COLD ADVECTION TONIGHT AND SKIES REMAINING
CLOUDY MOST OF THE NIGHT...DECIDED TO BUMP UP THE LOWS A COUPLE OF
DEGREES.
PREVIOUS DISCUSSION FOLLOWS.
SKIES SHOULD START OUT MOSTLY CLOUDY WITH A LOW PRESSURE SYSTEM
MOVING NORTHEAST OUT OF THE GULF AND THROUGH THE SOUTHEASTERN U.S. A
BIT OF MODEL DISAGREEMENT OVER HOW FAR NORTH PRECIPITATION
ASSOCIATED WITH THIS SYSTEM WILL GET DESPITE SIMILAR POSITIONS AND
STRENGTH FOR THE LOW PRESSURE CENTER. THE RAP AND GEM WERE THE
FURTHEST NORTH AND BRING THE PRECIP INTO THE FAR SOUTHEASTERN
COUNTIES. THE GFS KEEPS THE PRECIP WELL TO THE SOUTH...WHILE THE NAM
AND 0Z ECMWF JUST CLIP THE FAR SOUTHEAST WITH A HUNDREDTH OF QPF.
WITH THE VARIETY OF SOLUTIONS SHOULD CARRY A LOW CHANCE POP IN THE
FAR SOUTHEAST WITH DRY WEATHER BUT MOSTLY CLOUDY SKIES ELSEWHERE.
WENT WITH LOWS A DEGREE OR TWO BELOW GUIDANCE WITH EXPECTED COLD
ADVECTION.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
ISSUED AT 212 PM EST TUE JAN 15 2013
HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH THE SHORT TERM. A
LOW PRESSURE SYSTEM MOVING ACROSS THE HUDSON BAY WILL DRAG A COLD
FRONT ACROSS THE GREAT LAKES WEDNESDAY AND WEDNESDAY NIGHT...BUT IT LOOKS
LIKE ALL THE FORCING ASSOCIATED WITH IT WILL STAY WELL NORTH OF THE
AREA. ANOTHER SOUTHERN LOW PRESSURE SYSTEM WHICH WILL MOVE ACROSS
THE SOUTHEAST U.S. DURING THE SAME TIME APPEARS TO BE TOO FAR SOUTH
TO IMPACT POPS HERE. GUIDANCE IS IN GOOD AGREEMENT AND WILL USE AN
AVERAGE WHICH RESULTS IN NEAR NORMAL TEMPERATURES AND DRY WEATHER.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ISSUED AT 248 PM EST TUE JAN 15 2013
FOCUS OF THE EXTENDED PERIOD REMAINS ON THE ARRIVAL OF WHAT
INCREASINGLY APPEARS TO BE THE COLDEST AIRMASS OF THE SEASON AS A
PIEICE OF THE POLAR VORTEX BREAKS OFF AND AMPLIFIES THE UPPER
TROUGH OVER THE EASTERN PART OF THE COUNTRY.
WARMEST DAY OF THE PERIOD WILL BE SATURDAY AS SOUTHERLY FLOW AHEAD
OF A COLD FRONT ENABLES TEMPS TO RISE INTO THE 40S ACROSS THE
FORECAST AREA. LOW PRESSURE WILL TRACK THROUGH THE GREAT LAKES
SATURDAY NIGHT AND BRING THE COLD FRONT THROUGH CENTRAL INDIANA BY
EARLY SUNDAY. THE FRONT WILL USHER IN THE INITIAL SHOT OF COLDER
AIR...AS TEMPS ARE LIKELY TO FALL BACK INTO THE 20S AND LOWER 30S.
PASSAGE OF THE FRONT LOOKS TO BE DRY AS DEEPER MOISTURE IS FOCUSED
CLOSER TO THE LOW ACROSS THE GREAT LAKES. ARCTIC FRONT SET TO DIVE
INTO THE REGION ON MONDAY...USHERING IN MUCH COLDER AIR AS 850MB
TEMPS NOSEDIVE. ANTICIPATE SNOW SHOWERS TO ACCOMPANY THE FRONTAL
PASSAGE AND AS WIND FLOW ALIGNS TO THE NORTHWEST IN ITS WAKE...
LIKELY TO SEE SOME IMPACTS FROM LAKE ENHANCEMENT SNOW SHOWERS
THROUGH MONDAY NIGHT.
THE MUCH GREATER IMPACT WITH THE FRONTAL PASSAGE WILL BE TO
TEMPERATURES AS 850MB TEMPS ON BOTH THE ECMWF AND OP GFS FALL INTO
THE -23 TO -21C RANGE BY TUESDAY. IF THESE NUMBERS EVEN COME CLOSE
TO VERIFYING...HIGH TEMPS ON TUESDAY ARE LIKELY TO STRUGGLE INTO
THE 10-15 DEGREE RANGE AND PROVIDE CENTRAL INDIANA WITH THE
COLDEST AIR OF THE SEASON TO DATE. KNOWING HOW MODELS THIS FAR OUT
TEND TO UNDEROD THE DEPTH OF ARCTIC COLD AND WITH GROWING
CONFIDENCE IN THE INTENSITY OF THE COLD AIRMASS...HAVE CHOSEN TO
UNDERCUT ALLBLEND TEMPS BY 3 TO 4 DEGREES FOR BOTH MONDAY AND
TUESDAY. LOWS MAY BE DOWN NEAR ZERO BY TUESDAY NIGHT.
&&
.AVIATION /DISCUSSION FOR 160600Z TAF ISSUANCE/...
ISSUED AT 1125 PM EST TUE JAN 15 2013
VFR CONDITIONS ANTICIPATED THROUGHOUT THE FORECAST PERIOD. LOW
PRESSURE SHIFTS INTO THE SOUTHERN APPALACHIANS LATE
TONIGHT...MOISTURE ALOFT WILL ALSO BEGIN TO DEPART OFF TO THE EAST
AND CEILINGS ARE EXPECTED TO LIFT AND SCATTER IN THE HOURS
APPROACHING DAYBREAK. HIGH PRESSURE RIDGE THEN BUILDS INTO THE
REGION TODAY WITH BROAD SUBSIDENCE. WILL SEE SKIES BECOME
MOSTLY CLEAR. LIGHT AND VARIABLE WINDS LATE TONIGHT WILL SHIFT TO
W/SW AND INCREASE TO NEAR 10KTS BY THIS AFTERNOON.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP/JAS
SHORT TERM...CP
LONG TERM....RYAN
AVIATION...SMF
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1140 PM MST TUE JAN 15 2013
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 212 PM MST TUE JAN 15 2013
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOWS LONGWAVE TROUGH EXTENDING
FROM THE GREAT LAKES ACROSS CENTRAL KANSAS INTO NORTHERN MEXICO. CWA
IS CURRENTLY ON SUBSIDENT SIDE OF TROUGH AXIS UNDER SHORTWAVE
RIDGING. A WEAK SHORTWAVE TROUGH OVER MONTANA IS CURRENTLY MOVING
THROUGH N/NW FLOW ALONG THE BACK SIDE OF THE TROUGH.
THIS FEATURE IS EXPECTED TO SPLIT WITH A WEAK PIECE OF ENERGY MOVING
SOUTH ACROSS EASTERN COLORADO TONIGHT. WITH MAIN H3 JET AXIS WELL
NORTH OF THE CWA...I AM ONLY ANTICIPATING WEAK FORCING. MODEL
SOUNDINGS INDICATE A SATURATED LEVEL BETWEEN 800-600MB. WITH WEAK
FORCING IN THE WEST...AND VERY LITTLE IN THE WAY OF QPF SHOWN BY
AVAILABLE GUIDANCE I LIMITED SLIGHT CHANCE POPS TO WESTERN CWA THIS
EVENING AND OVERNIGHT...AND SCATTERED FLURRIES ELSEWHERE. EVEN IN
THE WEST WHERE MEASURABLE SNOW IS POSSIBLE I WOULD ONLY ANTICIPATE
A FEW TENTHS OF AN INCH WITH THIS SYSTEM.
SUBSIDENCE ALONG AND A MUCH DRIER AIR MASS WILL SPREAD EAST
WEDNESDAY WITH W/NW FLOW DEVELOPING. AIR MASS HAS ALREADY MODIFIED
WITH SHORTWAVE RIDGING THIS AFTERNOON AND SHOULD CONTINUE TO MODIFY
WED WITH HIGHS IN THE 40S/NEAR 50. THE SNOW PACK IN THE WEST AND NE
WILL STILL KEEP HIGHS SLIGHTLY COOLER...HOWEVER WITH WESTERLY WINDS
WE SHOULD STILL SEE HIGHS AROUND 40F AT THE COLDEST. A CONCERN FOR
WED WILL BE WINDS...WITH BREEZY TO WINDY CONDITIONS ANTICIPATED. I
AM LESS CONFIDENT HOW WINDY IT WILL BE WITH LIMITED MIXING HEIGHTS
BASED ON SOUNDING ANALYSIS. IF WE MIX MUCH HIGHER THAN CURRENT
SOUNDINGS SUGGEST...THEN WE COULD SEE ADVISORY CRITERIA MET...
ESPECIALLY IF WE USE THE NAM WINDS ALOFT. FOR NOW...I LIMITED WINDS
TO JUST UNDER ADVISORY CRITERIA WED AFTERNOON.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY)
ISSUED AT 1135 PM MST TUE JAN 15 2013
UPPER PATTERN ACROSS THE CONUS THIS PERIOD WILL FEATURE A RIDGE IN
THE WEST AND A TROUGH IN THE EAST. LOCAL AREA WILL FALL MAINLY
UNDER THE INFLUENCE OF THE RIDGE AND NO PRECIPITATION IS FORECAST.
AS FOR TEMPERATURES...MAIN CONCERN WILL BE FOR A BACK DOOR COLD
FRONT EARLY SUNDAY FOLLOWED BY A STRONGER COLD FRONT SUNDAY NIGHT
AND MONDAY. MONDAY WILL BE THE COLDEST DAY...BUT IT APPEARS COLD
SNAP WILL BE SHORT LIVED AS MODELS SHOW WARMING ON TUESDAY AND
WEDNESDAY AS COLD AIR LIFTS OUT TO THE NORTH UNDER SHORTWAVE
RIDGING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1001 PM MST TUE JAN 15 2013
KGLD RADAR GETTING RETURNS ON LIGHT SNOW/FLURRIES ACROSS THE AREA
TONIGHT. HOWEVER ONLY ISOLATED REPORTS OF SNOW REACHING THE
SURFACE. THIS AREA OF LIGHT SNOW IS MOVING SOUTH QUICKLY AND
EXPECT DECREASING CLOUDS BY EARLY WEDNESDAY MORNING. CURRENT
METARS ARE VFR AND THE LATEST TREND IS FOR INCREASING CLOUD BASES.
THERE IS POTENTIAL FOR BREEZY TO WINDY CONDITIONS ACROSS THE AREA
BUT MIXING HEIGHTS ARE BELOW 800MB. WINDS WILL DECREASE BY 00Z
THURSDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...024
AVIATION...032
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1130 PM CST TUE JAN 15 2013
...UPDATE TO AVIATION...
.DISCUSSION...
20Z WATER VAPOR SHOWS THE TROUGH AXIS OVERHEAD WITH THE UPPER
FLOW BEGINNING TO SPLIT WITH ENERGY BEING LEFT BEHIND OVER THE
SOUTHERN HIGH PLAINS. AT THE SURFACE...THE RIDGE AXIS STRETCHED
FROM THE TX PANHANDLE UP TO CHICAGO. THERE IS A MAXIMUM IN SURFACE
DEWPOINTS IMMEDIATELY DOWNSTREAM OF THE SNOW PACK IN SOUTHERN NEB.
WITH DAYTIME HEATING STEEPENING UP LOW LEVEL LAPSE RATES WITH
ADDED BOUNDARY LAYER MOISTURE...A CU FIELD HAS FORMED OVER NORTH
CENTRAL KS. WOULD EXPECT THESE CLOUDS TO DIMINISH WITH THE LOSS OF
DAYTIME HEATING AND THE 19Z RAP AND 18Z NAM SEEM TO SUPPORT THIS
IDEA...SO THINK SKIES SHOULD BECOME MOSTLY CLEAR OVERNIGHT.
FOR TONIGHT AND WEDNESDAY...THE FORECAST AREA IS EXPECTED TO BE
BETWEEN THE SPLITTING PATTERN WITH A CLOSED LOW REMAINING OVER THE
SOUTHERN PLAINS AND STRONG NORTHWEST FLOW REMAINING NORTH OVER THE
DAKOTAS AND UPPER MIDWEST. THEREFORE THERE IS EXPECTED TO BE LITTLE
OR NOW LARGE SCALE FORCING AFFECTING THE FORECAST AREA. WITH THIS
AND A DRY AIRMASS TO START OUT WITH...THE FORECAST REMAINS DRY.
THERE WILL BE A TROUGH AXIS/WIND SHIFT MOVE THROUGH THE AREA ON
WEDNESDAY. MODELS DO NOT SHOW ANY COLD AIR BEHIND THIS BOUNDARY AND
IN FACT HAVE WARM AIR ADVECTING IN FROM THE WEST WITH A DOWNSLOPE
WIND. THEREFORE HAVE CONTINUED WITH HIGHS GENERALLY AROUND 50. THERE
IS INDICATIONS FROM THE NAM AND GFS OF SOME SATURATED AIR BEHIND THE
FRONT WHICH COULD BE HELPED BY MELTING SNOW IN NEB...SO THINK SKIES
COULD BECOME PARTLY CLOUDY AS WINDS SHIFT TO THE WEST AND NORTHWEST.
THE PRESSURE GRADIENT SHOULD INCREASE OVERNIGHT AS THE SURFACE
TROUGH APPROACHES THE AREA. THIS SHOULD CAUSE WINDS TO GRADUALLY
INCREASE OVERNIGHT HELPING TO KEEP MIN TEMPS SEVERAL DEGREES WARMER
THAN THIS MORNING AND HAVE MIN TEMPS IN THE UPPER TEENS.
WOLTERS
CLEAR SKIES TO BE THE RULE THROUGH EARLY NEXT WEEK WITH NORTHWEST
FLOW ALOFT KEEPING MOISTURE RETURN IN CHECK AND MEAGER FORCING
MECHANISMS FOR CLOUDS LET ALONE PRECIPITATION. WEAK SURFACE HIGH
BUILDS IN THURSDAY WITH ACTUALLY A BIT OF WARMING AROUND
850MB...BUT THE LIMITED MIXING SHOULD KEEP HIGHS A FEW DEGREES
COOLER THAN WEDNESDAY. FRIDAY STILL LOOKING THE BE THE WARMEST DAY
WITH WEST TO SOUTHWEST WINDS DEVELOPING AHEAD OF A WAVE IN THE GREAT
LAKES. SATURDAY WILL SEE THE FIRST OF TWO COLD FRONTS MOVE IN DURING
THE DAY. MID TO LATE DAY COLD AIR ADVECTION SHOULD KEEP HIGHS IN THE
40S...WITH A MORE POTENT SHOT COMING IN THE SUNDAY NIGHT INTO MONDAY
TIME FRAME. THERE HAS BEEN SOME VACILLATION IN THE MODELS WITH HOW
FAR SOUTHWEST THE COLD AIR WILL REACH AND SPECIFIC TIMING OF THE
COLD AIR REMAINS UNCERTAIN. ALSO...THERE IS GOOD AGREEMENT WITH THE
UPPER PATTERN BREAKING DOWN TO A MORE ZONAL CHARACTER AS THE EASTERN
PACIFIC RIDGE BREAKS DOWN LEADING TO THE COLDEST AIR/S RESIDENCE
TIME IN THE CENTRAL PLAINS LIMITED. MONDAYS MAXES IN THE UPPER TEENS
TO MID 20S SEEM REASONABLE AT THIS POINT WITH MODIFICATION FOR
TUESDAY.
65
&&
.AVIATION...
VFR CONDITIONS WITH LIGHT WINDS EXPECTED THROUGH REMAINDER OF THE
FORECAST PERIOD. MODELS INDICATING A NEAR-SATURATED LEVEL AROUND
3000 FEET MID DAY ON WED...BUT GIVEN ITS SHALLOW NATURE ITS
POSSIBLE THAT IT WILL REMAIN SCT OR SIMPLY MIX OUT. WILL MENTION
SCT030 FOR THIS FORECAST AND INCREASE COVERAGE IN LATER ISSUANCES
SHOULD IT BE WARRANTED.
JL
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1029 PM MST TUE JAN 15 2013
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 212 PM MST TUE JAN 15 2013
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOWS LONGWAVE TROUGH EXTENDING
FROM THE GREAT LAKES ACROSS CENTRAL KANSAS INTO NORTHERN MEXICO. CWA
IS CURRENTLY ON SUBSIDENT SIDE OF TROUGH AXIS UNDER SHORTWAVE
RIDGING. A WEAK SHORTWAVE TROUGH OVER MONTANA IS CURRENTLY MOVING
THROUGH N/NW FLOW ALONG THE BACK SIDE OF THE TROUGH.
THIS FEATURE IS EXPECTED TO SPLIT WITH A WEAK PIECE OF ENERGY MOVING
SOUTH ACROSS EASTERN COLORADO TONIGHT. WITH MAIN H3 JET AXIS WELL
NORTH OF THE CWA...I AM ONLY ANTICIPATING WEAK FORCING. MODEL
SOUNDINGS INDICATE A SATURATED LEVEL BETWEEN 800-600MB. WITH WEAK
FORCING IN THE WEST...AND VERY LITTLE IN THE WAY OF QPF SHOWN BY
AVAILABLE GUIDANCE I LIMITED SLIGHT CHANCE POPS TO WESTERN CWA THIS
EVENING AND OVERNIGHT...AND SCATTERED FLURRIES ELSEWHERE. EVEN IN
THE WEST WHERE MEASURABLE SNOW IS POSSIBLE I WOULD ONLY ANTICIPATE
A FEW TENTHS OF AN INCH WITH THIS SYSTEM.
SUBSIDENCE ALONG AND A MUCH DRIER AIR MASS WILL SPREAD EAST
WEDNESDAY WITH W/NW FLOW DEVELOPING. AIR MASS HAS ALREADY MODIFIED
WITH SHORTWAVE RIDGING THIS AFTERNOON AND SHOULD CONTINUE TO MODIFY
WED WITH HIGHS IN THE 40S/NEAR 50. THE SNOW PACK IN THE WEST AND NE
WILL STILL KEEP HIGHS SLIGHTLY COOLER...HOWEVER WITH WESTERLY WINDS
WE SHOULD STILL SEE HIGHS AROUND 40F AT THE COLDEST. A CONCERN FOR
WED WILL BE WINDS...WITH BREEZY TO WINDY CONDITIONS ANTICIPATED. I
AM LESS CONFIDENT HOW WINDY IT WILL BE WITH LIMITED MIXING HEIGHTS
BASED ON SOUNDING ANALYSIS. IF WE MIX MUCH HIGHER THAN CURRENT
SOUNDINGS SUGGEST...THEN WE COULD SEE ADVISORY CRITERIA MET...
ESPECIALLY IF WE USE THE NAM WINDS ALOFT. FOR NOW...I LIMITED WINDS
TO JUST UNDER ADVISORY CRITERIA WED AFTERNOON.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 212 PM MST TUE JAN 15 2013
FORECAST PROBLEMS WILL BE THE AMOUNT OF WARMUP BEFORE THE NEXT VERY
COLD AIR MASS ARRIVES AND HOW COLD WILL THAT AIR MASS ALONG WITH
WHEN IT ARRIVES. SATELLITE SHOWING AN AMPLIFIED FLOW STARTING WITH
A BROAD...DEEP AND COMPLICATED UPPER TROUGH OVER THE WESTERN HALF OF
THE PACIFIC WHICH IS MAINTAINING/AMPLIFYING AN UPPER RIDGE NEAR THE
WEST COAST OF NORTH AMERICA. THIS TRANSITIONS TO A TROUGH OVER THE
CENTER OF THE COUNTRY WHICH HAS/CONTINUES TO SPLIT. WARMER AIR MASS
STARTING TO WORK ITS WAY INTO THE REGION.
AT JET LEVEL...THE MODELS INITIALIZED FINE WITH THE ECMWF SLIGHTLY
WORSE THAN THE OTHERS. SATELLITE AND UPPER AIR ANALYSIS SHOW THE
MODELS HAVE INITIALIZED WELL AT MID LEVELS. HOWEVER WOULD HAVE TO
SLIGHTLY FAVOR THE UKMET/CANADIAN OVER THE NAM/ECMWF. AT THE
SURFACE THE SREF WAS DOING A LITTLE BETTER THAN THE ECMWF. THE UKMET
WAS DOING A LITTLE BETTER THAN THE ECMWF AND GFS ON THE LOW LEVEL
THERMAL FIELD.
WEDNESDAY NIGHT/THURSDAY...MAIN STORM TRACK REMAINS WELL NORTH OF
THE AREA AND UNDER SUBSIDENCE FROM THE JET. FLOW ALOFT IS MORE
NORTHWEST WITH LITTLE TO NO CLOUD COVER EXPECTED AT THIS TIME.
WINDS MAY DROP OFF LATE IN THE NIGHT MAINLY IN THE WEST. SURFACE
RIDGE MOVES THROUGH EARLY IN THE DAY ON THURSDAY WITH WINDS SHIFTING
MORE TOWARD THE SOUTH IN THE AFTERNOON. ADJUSTED TEMPERATURES UP A
LITTLE.
THURSDAY NIGHT/FRIDAY...STORM TRACK STILL NORTH OF THE AREA WITH
WEST TO NORTHWEST FLOW ALOFT. THERE MAY BE A LITTLE MORE CLOUD
COVER DURING THE NIGHT AS A WEAK SYSTEM MOVES THROUGH IN THE FLOW
BUT AGAIN LITTLE TO NO CLOUD COVER EXPECTED. DOWNSLOPE COMPONENT IS
MUCH BETTER ON THE WINDS AND ALL MODELS ARE SIMILAR IN THEIR INCREASE
IN THE 850 MB TEMPERATURES. ALSO WOULD EXPECT THE WARM AIR ADVECTION
AND DOWNSLOPE WILL BE BETTER THAN DEPICTED SINCE THIS WILL BE AHEAD
OF THE INITIAL PUSH OF COLDER THAT WILL COME IN ON SATURDAY. SO FELT
COMFORTABLE IN WARMING UP MAXES FROM THE CURRENT PACKAGE. IT IS
POSSIBLE THAT ADDITIONAL RAISING OF THE MAXES WILL BE POSSIBLE.
FRIDAY NIGHT THROUGH TUESDAY...BIG CHANGE IN THE WEATHER...TO MUCH
COLDER TEMPERATURES THIS WEEKEND INTO THE BEGINNING OF NEXT WEEK...
STILL LOOKS ON TRACK. THERE ARE STILL DIFFERENCES IN THE MODELS BUT
THEY ARE MUCH CLOSER THAN YESTERDAY WHICH INCREASES CONFIDENCE ON
THE MAGNITUDE AND ESPECIALLY THE TIMING. SATURDAY LOOKS TO BE VERY
TRICKY. THE INITIAL PUSH IS COMING IN A LITTLE FASTER AND LOOKS
LIKE IT MAY ARRIVE LATE MORNING INTO EARLY AFTERNOON ESPECIALLY IN
THE NORTHEAST HALF OF THE AREA. SO THERE LOOKS TO BE A GOOD GRADIENT
ACROSS MY AREA WHICH WILL NEED TO BE RESOLVED AS WE GET MUCH CLOSER
TO THE DAY. AT THIS TIME TOOK WHAT WAS GIVEN TO ME BY THE CRH_INIT
AND NUDGED DOWN A LITTLE AS I BLENDED WITH NEIGHBORS.
FIRST PUSH OF THE COLD AIR LOOKS TO BE WELL ENTRENCHED BY 12Z
SUNDAY. MODELS WANT TO SCOUR OUT THE COLD AIR DURING THE DAY AS WINDS
SHIFT TO THE WEST BEFORE THE COLDEST AIR ARRIVES SUNDAY NIGHT. NOT
ENTIRELY SOLD ON THAT. SO AFTER COLLABORATION WITH NEIGHBORS DID
LOWER MAXES FROM WHAT WAS GIVEN BY THE INIT. VERY COLD AIR TO
ARRIVE SUNDAY NIGHT INTO MONDAY PER MODEL CONSENSUS. AFTER
COLLABORATION FELT VERY COMFORTABLE IN LOWERING MAXES SIGNIFICANTLY.
WHEN THE COLD AIR COMES IN SUNDAY NIGHT AND MONDAY FLURRIES WILL BE
POSSIBLE. THEN MODELS WANT TO REALLY SCOUR OUT THE COLD AIR ON
TUESDAY AND AGAIN NOT SOLD ON THAT. HOWEVER...THE INIT GAVE ME COOLER
TEMPERATURES THAN WHAT THE MODEL 850 TEMPERATURES SAY. SO AGREED WITH
SURROUNDING OFFICES IN LEAVING THOSE TEMPERATURES ALONE FOR NOW.
THANKS TO ALL FOR THE COLLABORATION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1001 PM MST TUE JAN 15 2013
KGLD RADAR GETTING RETURNS ON LIGHT SNOW/FLURRIES ACROSS THE AREA
TONIGHT. HOWEVER ONLY ISOLATED REPORTS OF SNOW REACHING THE
SURFACE. THIS AREA OF LIGHT SNOW IS MOVING SOUTH QUICKLY AND
EXPECT DECREASING CLOUDS BY EARLY WEDNESDAY MORNING. CURRENT
METARS ARE VFR AND THE LATEST TREND IS FOR INCREASING CLOUD BASES.
THERE IS POTENTIAL FOR BREEZY TO WINDY CONDITIONS ACROSS THE AREA
BUT MIXING HEIGHTS ARE BELOW 800MB. WINDS WILL DECREASE BY 00Z
THURSDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...032
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
452 AM EST WED JAN 16 2013
.SYNOPSIS...
WINTRY PRECIPITATION WILL TAPER OFF THIS MORNING. A SURGE OF
COLDER AIR WILL MOVE ACROSS THE LOWER LAKES THURSDAY AND BRING
SCATTERED SNOW SHOWERS TO THE HIGHER TERRAIN. A STORM SHOULD MOVE
THROUGH THE MID-ATLANTIC STATES THURSDAY...BUT IT SHOULD STAY TO
THE SOUTH OF THE AREA. TEMPERATURES WILL MODERATE A BIT ON
SATURDAY BEFORE MUCH COLDER AIR ARRIVES SUNDAY AND MONDAY.
TEMPERATURES MAY DIP INTO THE SINGLE DIGITS IN PARTS OF THE AREA
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MOST RECENT RAP/RUC AND HRRR RUNS PORTRAY THE CURRENT RADAR
TRENDS VERY NICELY...AND HIGH CONFIDENCE IN THESE SOLUTIONS IS THE
RESULT. THE BREAK/VERY LIGHT PRECIP SHOULD BE THE ESSENTIAL END
TO THE BEST ACCUMULATIONS. ONE OR TWO MORE WEAK SURGES OF HIGHER
PRECIP RATES COULD AFFECT THE CENTRAL AND NORTHERN AREAS THIS
MORNING. THE FIRST OF WHICH APPEARS TO BE MOVING THRU THE LAURELS
RIGHT NOW. THINGS WILL DEFINATELY BE TAPERING OFF THROUGH THE
EARLY MORNING. WHILE A DUSTING/THIN ACCUMULATION OF SNOW OR SLEET
IS POSSIBLE ACROSS THE NORTH AFTER 10 OR 11 AM...IT APPEARS IT
PROBABLY WON/T WARRANT EXTENDING THE ADVY AND WILL LET IT RIDE AS
IS FOR NOW. WILL ALSO KEEP THE REST OF THE ADVY IN PLACE WITH
MORNING TRAVEL PROBLEMS LIKELY DUE TO SECONDARY AND TERTIARY ROADS
STILL COVERED WITH SNOW/ICE FOR A FEW HOURS AFTER SUNRISE. TEMPS
ARE AT OR BELOW FREEZING FOR ALL BUT KCXY AT THIS HOUR. THIS KEEPS
THE THREAT OF FZRA GOING FOR THE NEXT FEW HRS IN THE LOWER SUSQ.
SKY WILL REMAIN CLOUDY FOR A GOOD PORTION OF THE DAY...BUT SOME
CLEARING IS POSSIBLE THIS AFTN - ESP IN THE N.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
BASE OF THE BROAD UPPER TROUGH WILL BE OVERHEAD ON
THURSDAY...KEEPING A SIGNIFICANT SHORT WAVE TROUGH ROLLING EAST
THROUGH THE SMOKIES. THIS WAVE LOOKS TO DEVELOP FURTHER AND BECOME
A FAIRLY DECENT PRECIP/SNOW THREAT -- BUT SHOULD ALSO STAY TO THE
SOUTH OF THE AREA. THE FAR NRN EDGE OF THE PRECIP SHIELD MAY TOUCH
THE FAR SE ON THURS AFTN/EVENING...BUT ONLY A CHC POP IS WARRANTED
AT THIS POINT. THE BIGGER STORY WILL BE THE ARCTIC FRONT MOVING
DOWN ACROSS THE GREAT LAKES ON THURSDAY. WHILE THE 8H TEMPS DIP
GRADUALLY TODAY AND TONIGHT...THE COLD ADVECTION REALLY RAMPS UP
ON THURSDAY. THIS SHOULD CREATE SNOW SHOWERS AND PERHAPS A FEW
SQUALLS IN THE NWRN MTS. WILL HOLD ONTO CURR/SCT POPS FOR A BIT
DUE TO TIMING DIFFERENCES.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
SCATTERED -SHSN ARE POSSIBLE ACROSS NORTHERN AND WESTERN PA IN
THE CHILLY NORTHWESTERLY FLOW BEHIND THE FRONT. BY FRIDAY...850MB
TEMPS ARE ALREADY ON THE RISE AS HIGH PRESSURE PUSHES OFF THE EAST
COAST AND SOUTHERLY FLOW DEVELOPS.
SATURDAY WILL BE A MILD DAY...BEFORE A MORE POTENT COLD FRONT
CROSSES THE AREA SAT NIGHT/SUNDAY. ANOTHER SHOT OF COLDER AIR
WILL BE ACCOMPANIED BY A RENEWED CHC OF SHSN ACROSS NORTHERN AND
WESTERN PA ON SUNDAY.
THE EARLY PART OF NEXT WEEK LOOKS WINTER-LIKE...WITH BELOW-NORMAL
TEMPERATURES. THE 12Z OPERATIONAL GFS AND ECMWF BOTH SWING A PIECE
OF ENERGY AROUND THE BASE OF THE EASTERN U.S. TROUGH IN THE MON/TUES
TIMEFRAME...BUT CURRENTLY HAVE COASTAL LOW PRES DEVELOPMENT
OCCURRING TOO FAR NORTH/EAST OF THE AREA TO HAVE MUCH OF AN IMPACT.
&&
.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
A LARGE AREA OF HEAVY SNOW IS OVER MUCH OF SOUTH CENTRAL
PA...ALONG WITH A MIXTURE OF RAIN...SLEET...AND FREEZING
RAIN ACROSS THE SE.
ADVERSE CONDITIONS WILL COTINUE OVERNIGHT INTO WED MORNING...
BEFORE IMPROVING.
EARLIER DISCUSSION BELOW.
SCATTERED PRECIPITATION CONTINUES TO SPREAD ACROSS THE REGION.
SNOW SHOULD DOMINATE ACROSS CENTRAL PA NORTH...WITH A WINTRY MIX
ACROSS THE SOUTHEAST...AND FREEZING RAIN AND SNOW MIX ACROSS THE
LAURELS...IN IFR AND LOWER ACROSS ALL TAF SITES BY 06Z...WITH BFD
BY 09Z AT THE LATEST. PERIODS OF -FZRA FROM SHIFTING WARM AIR
ALOFT FROM 07Z TO 12Z ARE POSSIBLE IN THE SE. HIGHEST QPF WILL OCCUR
ACROSS SOUTHERN TIER...ALONG WITH HIGHEST THREAT OF ICING
CONDITIONS IN THE KJST- KAOO AREA. ALL AREAS SHOULD CLEAR BETWEEN
18 TO 21Z TOMORROW AFTERNOON.
OUTLOOK...
WED...AM WINTRY MIX/LOW CIGS.
THU...SHSN/OCNL MVFR POSS NW MTNS. WINDY.
FRI-SAT...NO SIG WX EXPECTED.
SUN...SHSN/OCNL MVFR POSS NW MTNS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
PAZ012-017>019-024>028-033>037-041-042-045-046-049>053-056>059-
063>066.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...EVANEGO
AVIATION...CERU/MARTIN/RXR
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
916 PM MST TUE JAN 15 2013
.UPDATE...04Z SURFACE ANALYSIS HAD WARM FRONT FROM CENTRAL ND INTO
WESTERN NE. STRONG WARM AIR ADVECTION/BAND OF FRONTOGENESIS HAS
BROUGHT -SHSN TO MUCH OF THE CWA THIS EVENING...WITH TAIL END OF
MOISTURE STARTING TO BE SEE OVER MT/ND PER BOWMAN RADAR. UPSLOPE
-SHSN STILL PULSING OVER THE BLACK HILLS...BUT THAT SHOULD END IN
A COUPLE OF HOURS. 30-45KT LOW LEVEL WINDS NOTED ON KUNR/UPSTREAM
SOUNDINGS AS WELL AS LATEST RAP/NAM GUIDANCE. NOT EVERYTHING
REACHING THE GROUND WITH BOUNDARY LAYER PARTIALLY DECOUPLED AND
WARM AIR ADVECTION. DO NEED TO UP WINDS SOME THOUGH...BASED ON
LATEST TRENDS. HAVE ALSO ADJUSTED POPS FOR RADAR/TEMPERATURE TRENDS.
WILL ALLOW ADVISORY OVER THE BLACK HILLS TO EXPIRE ON SCHEDULE
GIVEN ABOVE THINKING.
&&
.AVIATION...06Z TAFS
IFR CIGS/VSBYS ASSOCIATED WITH -SHSN WILL EXIT THE CWA BY 09Z.
BEHIND IT...VFR CONDITIONS WILL DEVELOP WITH CIGS FROM 4-8KFT
RISING TO AC/CI LEVEL WEDNESDAY.
.PREV DISCUSSION... /ISSUED 250 PM MST TUE JAN 15 2013/
DISCUSSION...VIGOROUS DEEP LAYER WAA AND HEIGHT RISES ONGOING
ACROSS THE FA...WITH UPSLOPE ENHANCEMENT BEGINNING TO REV UP. POTENT
UPPER LEVEL RIDGING AND ASSOCIATED WAA WILL CONTINUE THROUGH MOST OF
THE PERIOD...ALTHOUGH A PASSING NORTHERN STREAM DISTURBANCE WILL
OFFER A SHORT LULL IN WAA ACROSS THE NORTHERN HALF OF THE FA
WED...WITH WAA BEGINNING TO SPREAD OVER THE REGION AGAIN WED NIGHT
THUR AS THE REGION REMAINS ON THE WARM SIDE OF A VERY STRONG
BAROCLINIC ZONE. NEAR SATURATED WAA WILL CONTINUE THROUGH THIS
EVENING...BEFORE DRIER AIR ADVECTS INTO THE FA...SUPPORTING AN END
TO UPGLIDE/UPSLOPE INDUCED SNOW.
STRONG LOW CENTERED OMEGA MAX IS OFFERING STAUNCH LOW LEVEL LIFT IN
A NEAR SATURATED BL...WITH A RISING FROUDE NUMBER IN THE NORTHERN
BLACK HILLS. RAP POINT SOUNDINGS IN FAR WESTERN LAWRENCE COUNTY
INDICATE A DEEPLY SATURATED BL. HOWEVER...WAA IS SHUNTING THE LAYER
OF MAXIMUM OMEGA OUT OF THE DGZ INTO INCREASINGLY WARMER AIR. THIS
HAS ALLOWED THE PRODUCTION OF FREEZING DRIZZLE AT TIMES...WHICH IS
EXPECTED TO MIX WITH UPSLOPE SNOWS THROUGH THE AFTERNOON/EVENING..AS
LL PROFILES WARM AND MID LEVEL DRYING COMMENCES. SNOW MAY MIX WITH
OR CHANGE OVER TO ALL FREEZING DRIZZLE AT TIMES...ESP WITH
OSCILLATING INTENSITY OF UPSLOPE ENHANCEMENT AND ANY SEEDER-FEEDER
PROCESS. STILL EXPECT ANOTHER 1-3 INCHES THROUGH THE EVENING IN TH
ADV...WITH LOCALLY HIGHER AMOUNTS WHERE SNOW PERSISTS...ALTHOUGH ZL
MIXING MAY LIMIT SNOWS SIG IN SOME AREAS. WILL KEEP THE ADV GOING
THROUGH THE CURRENT EXPIRATION TIME.
BREEZY CONDITIONS CAN BE EXPECTED THROUGH WED GIVEN THE LL BAROCLINIC
ZONE IN PLACE ACROSS THE REGION/EXPECTED PRESSURE FALLS...ALTHOUGH
WAA WILL OFFSET THE INTENSITY OF WINDS TONIGHT. A LITTLE BETTER
MIXING AND WEAK CAA ACROSS THE NORTH WILL ALLOW FOR BREEZY
CONDITIONS OVER THE SD PLAINS ON WED.
DRIER AIR WILL WORK INTO THE AREA...WITH SIG AMOUNTS OF HIGH CLOUDS
EXPECTED TO REMAIN GIVEN THE LOCATION OF THE UPPER JET. IN
ADDITION...A WEAK SECONDARY COLD FRONT/TROUGH WILL ADVECT THROUGH
THE AREA...SUPPORTING SOME MID CLOUD ACROSS THE NORTH...WITH
DECREASING CLOUDS THROUGH THE WED PERIOD. ALTHOUGH VERY WARM
PROFILES ARE PROGGED JUST ABOVE THE SFC...HIGH CLOUD COVER MAY LIMIT
T RISES TO A POINT WED...ESP AWAY FROM DOWNSLOPE AREAS AND WHERE A
DEEPER SNOW PACK IS IN PLACE. LOWS WILL REMAIN TRICKY...ESP WED
NIGHT WHEN WAA AND A LINGERING PRESSURE GRADIENT IN PLACE IS
ALLOWING SOME MODEL PROGS TO FORECAST MUCH WARMER TEMPS THAN SOME
OTHER SOLUTIONS. HAVE SIDED SOME TOWARD THIS WARMER SOLUTION WHICH
HAS BEEN EVIDENT THE LAST SEVERAL RUNS...ALTHOUGH QUESTIONS ON SNOW
COVER AND DECOUPLING REMAIN. HAVE INCORPORATED SOME DOWNSLOPE
EFFECTS ON THUR/S HIGHS WHICH WILL AGAIN REMAIN TRICKY.
EXTENDED...FAST NORTHWEST FLOW WILL CONTINUE OVER THE NORTHERN
PLAINS THROUGH EARLY NEXT WEEK. THE FORECAST AREA WILL REMAIN UNDER
THE INFLUENCE OF THE WESTERN RIDGE FOR ONE MORE DAY ON FRIDAY...WITH
DRY CONDITIONS AND MILD TEMPERATURES. CHANGES WILL COME THIS WEEKEND
AS A COMPACT SHORTWAVE DIVES THROUGH NORTHERN MINNESOTA...DRAGGING A
STRONG COLD FRONT ACROSS THE DAKOTAS FRIDAY NIGHT INTO SATURDAY.
TEMPERATURES WILL COOL DRAMATICALLY BY SUNDAY AND MONDAY AS ARCTIC
AIR SETTLES ACROSS THE NORTHERN PLAINS. ANOTHER WEAKER SHORTWAVE
WILL CROSS THE DAKOTAS ON SUNDAY...GIVING THE AREA A CHANCE FOR
LIGHT SNOW THROUGH SUNDAY NIGHT.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING FOR CENTRAL
BLACK HILLS-NORTHERN BLACK HILLS.
WY...WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING FOR WYOMING
BLACK HILLS.
&&
$$
SHORT TERM...WFO UNR
LONG TERM...WFO UNR
AVIATION...HELGESON
UPDATE...HELGESON
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
356 AM CST WED JAN 16 2013
.SHORT TERM...TODAY THROUGH FRIDAY
355 AM CST WED JAN 16 2013
AT 3 AM...A SHORT WAVE TROUGH WAS MOVING SOUTHEAST ACROSS THE
NORTHERN TWO-THIRDS OF MINNESOTA AND NORTHWEST WISCONSIN. AREAS OF
SNOW IS BEING REPORTED ACROSS MINNESOTA AND EASTERN SOUTH DAKOTA.
THE 280-290K ISENTROPIC SURFACES SHOW THAT ONLY 10 MB OF LIFT WILL
BE NEEDED FOR SATURATION TO OCCUR. NEITHER THE NAM/WRF OR THE GFS
IS THAT IMPRESSIVE WITH THEIR OMEGA IN THE BUFKIT SOUNDINGS.
MEANWHILE THE RAP SHOWS THAT THERE WILL BE 5 TO 10 MICROBARS OF
LIFT. IN ADDITION...THE MESO MODELS SHOW THAT SOME LIGHT SNOW WILL
FALL ACROSS THE AREA. AREAS SOUTH OF THE INTERSTATE 94 CORRIDOR
WILL LIKELY ONLY SEE A DUSTING OF SNOW...SO KEPT PRECIPITATION
PROBABILITIES IN THE 20 TO 40 PERCENT RANGE. MEANWHILE NORTH OF
THIS AREA...THERE IS DEEPER MOISTURE AND STRONGER FORCING...SO
WENT WITH 50 TO 80 PERCENT PRECIPITATION PROBABILITIES. SNOWFALL
AMOUNTS IN THESE AREAS LOOK TO BE AROUND A HALF INCH.
DESPITE CLOUDS ACROSS THE AREA TODAY...TEMPERATURES WILL WARM
INTO THE 30S ACROSS THE AREA. LIKE THE PAST COUPLE OF THE
DAYS...THE NAM/WRF WAS INITIALIZED WITH WAY TOO MUCH SNOW COVER
ACROSS WISCONSIN /2 TO 8 INCHES/ AND EAST CENTRAL MINNESOTA /5 TO
8 INCHES/. SINCE THE MODEL IS TRYING TO MELT THIS SNOW...ITS
TEMPERATURES ARE TOO COLD...SO WENT WITH THE WARMER GFS AND ECMWF.
FOR THIS AFTERNOON AND EVENING...THE MODELS ARE SHOWING THAT THE
SECOND SHORT WAVE TROUGH IS MUCH WEAKER. AS A RESULT...THERE WILL
LIKELY NOT BE ENOUGH MOISTURE OF LIFT FOR ANOTHER ROUND OF SNOW TO
DEVELOP. LOOKING UPSTREAM...THERE IS NO PRECIPITATION ASSOCIATED
WITH THIS WAVE...THUS...TOOK OUT THE MENTION FOR PRECIPITATION.
FOR TONIGHT...A COLD FRONT WILL MOVE SOUTH THROUGH THE AREA. LOW
TEMPERATURES ON TUESDAY MORNING WILL RANGE 0 TO 15 DEGREES. THIS
IS CLOSE TO WHAT WE NORMALLY SEE IN MID-JANUARY.
ON THURSDAY NIGHT...THE MODELS CONTINUE TO SHOW THAT A WARM FRONT
WILL MOVE NORTH ACROSS THE AREA. THE GFS...GEM...AND ECMWF ARE IN
GOOD AGREEMENT THAT THERE WILL BE ENOUGH MOISTURE AND LIFT FOR
SOME LIGHT SNOW TO DEVELOP ALONG AND NORTH OF THE INTERSTATE 94
CORRIDOR. SNOWFALL AMOUNTS LOOK LIKE THEY WILL BE A HALF INCH OR
LESS.
ON FRIDAY...A LOW PRESSURE SYSTEM WILL MOVE ACROSS NORTHERN
MINNESOTA AND NORTHERN WISCONSIN. STRONG SOUTHWEST WINDS ALOFT
WILL BRING WARM AIR QUICKLY INTO THE REGION. IN ADDITION...THE
CLOUDS WILL DECREASING DURING THE DAY/ THE COMBINATION OF
SOUTHWEST WINDS...SUNSHINE...AND NO SNOW COVER...TEMPERATURES
SHOULD EASILY CLIMB INTO THE 30S AND LOWER 40S. IF THE ECMWF IS
CORRECT...THE TEMPERATURES MAY BE EVEN A COUPLE MORE DEGREES
WARMER. IT HAS BEEN SHOWING HIGHS IN THE LOWER AND MID 40S FOR THE
PAST 4 NIGHTS. AS STATED IN EARLIER...THE NAM/WRF HAS WAY TOO MUCH
SNOW ACROSS WISCONSIN...THUS...THREW OUT ITS MOS GUIDANCE.
.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
355 AM CST WED JAN 16 2013
ON FRIDAY NIGHT...A COLD FRONT WILL BRIEFLY SURGE SOUTHWARD INTO
THE AREA AND THEN MOVE BACK NORTH AS A WARM FRONT AS A LOW
PRESSURE SYSTEM MOVES INTO NORTHWEST MINNESOTA. THE 275-285K
ISENTROPIC SURFACES SHOW THAT IT WILL TAKE 50 TO 100 MB FOR
SATURATION TO OCCUR. AS A RESULT...KEPT THE FORECAST DRY FOR NOW.
HIGH TEMPERATURES ON SATURDAY WILL RANGE FROM THE MID 20S TO MID 30S.
FROM LATE SATURDAY AFTERNOON INTO SATURDAY NIGHT...AN ARCTIC COLD
FRONT WILL MOVE SOUTH THROUGH THE FORECAST AREA. THE BEST MOISTURE
AND LIFT LOOKS TO BE MAINLY ALONG AND NORTH OF THE INTERSTATE 94
CORRIDOR. DUE TO THIS...KEPT LIGHT SNOW CHANCES MAINLY CONFINED
TO THIS AREA. LIKE LAST NIGHT...THE MODEL SOUNDINGS CONTINUE TO
SUGGEST THAT THE WINDS MAY BRIEFLY GUST INTO THE 35 TO 45 MPH
RANGE IN THE WAKE OF THIS FRONT.
ON SUNDAY NIGHT AND MONDAY MORNING...THE MODELS CONTINUE TO SHOW
THAT ANOTHER ARCTIC COLD FRONT WILL MOVE SOUTH THROUGH THE REGION.
THE GEM...GFS...AND ECMWF SUGGEST THAT SOME LIGHT SNOW WILL BE
ASSOCIATED WITH THIS FRONTAL PASSAGE. 850 MB TEMPERATURES ARE
AROUND 1.5 STANDARD DEVIATIONS BELOW NORMAL IN THE GFS AND AROUND
2 STANDARD DEVIATIONS BELOW NORMAL IN THE ECMWF. IT LOOKS LIKE
MUCH OF THE AREA WILL SEE HIGH TEMPERATURES REMAINING IN THE
SINGLE DIGITS. WIND CHILLS ON THIS MORNING LOOK TO BE IN THE 10 TO
20 BELOW RANGE.
ON MONDAY NIGHT...THE MODELS CONTINUE TO SHOW THAT LOW TEMPERATURES
WILL LIKELY RANGE FROM 5 TO 20 BELOW. WITH TEMPERATURES THIS COLD...
ANY WIND AT ALL WILL PRODUCE WIND CHILLS IN THE ADVISORY CRITERIA
/20 TO 35 BELOW/.
EARLY NEXT WEEK...THE MODELS CONTINUE TO SHOW THAT A STRONG SUDDEN
STRATOSPHERIC WARMING EVENT WILL TAKE PLACE ACROSS THE NORTH
CENTRAL PACIFIC. THIS WILL RESULT IN A LONG WAVE TROUGH QUICKLY
DEVELOPING ACROSS THIS AREA. THIS IS TURN WILL GIVE AN EASTERN
NUDGE TO THE LONG WAVE RIDGE ACROSS THE EAST PACIFIC AND WESTERN
NORTH AMERICA. AS THIS OCCURS...THE COLDEST AIR SHOULD START TO
SHIFT OUT OF THE AREA ON TUESDAY AND TUESDAY NIGHT. BOTH THE
DETERMINISTIC AND ENSEMBLE MEMBERS SHOW THIS OCCURRING...SO
CONFIDENCE IS FAIRLY HIGH THAT THIS LATEST BOUT OF ARCTIC AIR WILL
BE A SHORT LIVED.
&&
.AVIATION...THROUGH 06Z THURSDAY
1141 PM CST TUE JAN 15 2013
FOCUS OF THIS FORECAST IS ON A LOW PRESSURE SYSTEM ENCOMPASSING
SOUTH CENTRAL CANADA INTO THE NORTHERN PLAINS.
PLENTY OF DRY AIR STILL EXISTS AHEAD OF THIS SYSTEM OVER THE
FORECAST AREA. THIS DRY AIR WILL HELP KEEP VFR CONDITIONS FOR
THE EARLY MORNING HOURS. SOUTH TO SOUTHWEST WINDS HAVE INCREASED
AHEAD OF THE SYSTEM...AT THE SURFACE AT KRST WHERE GUSTS ARE
UPWARDS OF 20-25 KT...AND AT 1000-15000 FT ABOVE THE SURFACE AT
KLSE WHERE WINDS ARE 40-45KT. LOOK FOR THESE CONDITIONS TO PERSIST
THROUGH THE EARLY MORNING HOURS.
A BAND OF SNOW ASSOCIATED WITH THE SYSTEM...CURRENTLY ACROSS
THE NORTH HALF OF MINNESOTA...IS FORECAST TO IMPACT THE TAF SITES
WEDNESDAY MORNING...BETWEEN 13-18Z. THE TAF SITES LOOK TO BE ON
THE LIGHTER SOUTHERN END OF THE BAND...THUS HAVE KEPT VISIBILITIES
AT MVFR. AT MOST A COUPLE TENTHS OF ACCUMULATION WOULD OCCUR WITH
THE SNOW. CEILINGS SHOULD QUICKLY DROP TO MVFR AS WELL WITH THE
BAND OF SNOW...WHICH THEN LOOK TO HANG AROUND THROUGH THE
AFTERNOON AND EVEN INTO THE EVENING. LOW LEVEL WIND SHEAR ENDS AT
KLSE AROUND THE TIME THE BAND OF SNOW MOVES IN...SINCE THE LOW
LEVEL JET PUSHES OFF TO THE EAST. PLAN ON THE WINDS TO TURN WEST
AND NORTHWESTERLY AS THE LOW PRESSURE SYSTEMS COLD FRONT MOVES
INTO THE TAF SITES IN THE AFTERNOON. WINDS SHOULD ALSO SLOWLY DECREASE
SINCE THE PRESSURE GRADIENT BEHIND THE COLD FRONT IS NOT AS TIGHT
AS WHAT IS CURRENTLY IN PLACE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
355 AM CST WED JAN 16 2013
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
825 AM EST WED JAN 16 2013
.UPDATE (REST OF TODAY THROUGH FRIDAY)...
13Z WATER VAPOR AND H4 RAP ANALYSIS SHOW A CONTINUED AMPLIFIED UPPER
LEVEL PATTERN OVER THE CONUS THIS WEDNESDAY MORNING. MAIN LONGWAVE
TROUGH AXIS OVER THE CENTRAL PORTION OF THE COUNTY IS UNDERGOING A
FRACTURE EVENT...WITH NORTHERN ENERGY LOBE CROSSING THE GREAT LAKES
REGION AND SOUTHERN VORTICITY CENTER NOW CUTTING OFF OVER CENTRAL
TEXAS. THIS SOUTHERN ENERGY WILL HOWEVER ALSO BE PROGRESSIVE...AND
IS FORECAST TO BECOME QUITE A POTENT LITTLE UPPER LOW AS IT MOVES
ALONG THE NORTHERN GULF COAST THE NEXT 24-36 HOURS.
CLOSER TO HOME...THE PENINSULA WILL EXPERIENCE ITS FINALLY DAY UNDER
THE SUPPRESSION OF THE UPPER RIDGE. THIS RIDGE HAS PROVIDED A LONG
DURATION OF DRY AND UNSEASONABLY WARM WEATHER FOR OVER A WEEK. THE
STRONG SYSTEM APPROACHING FORM THE WEST WILL COMPLETELY BREAK DOWN
THE RIDGE BY THIS TIME TOMORROW AND BRING COOLER AND MORE SEASONABLE
CONDITIONS FOR THE END OF THE WEEK. AT LEAST FOR NOW...THE RIDGE IS
STILL DOMINANT IN OUR WEATHER. 12Z KTBW SOUNDING PROFILE CONTINUES
TO SHOW A WELL-DEFINED SUBSIDENCE INVERSION AROUND 830MB AND A DRY
PROFILE ABOVE THIS LEVEL. THE DEEP SUPPRESSION AND DECENT DIURNAL
MIXING SHOULD ALLOW TEMPS TO APPROACH OR SURPASS 80 FOR ONE FINAL
DAY AWAY FROM THE IMMEDIATE COAST.
AT THE SURFACE...HIGH PRESSURE CENTERED NORTH OF THE BAHAMAS
CONTINUES TO RIDGE BACK TO THE WEST INTO THE EASTERN GULF OF MEXICO.
FURTHER WEST WE FIND A CURRENTLY QUASI-STATIONARY FRONTAL BOUNDARY
EXTENDING FROM THE CENTRAL GULF NORTHWARD TO AL/GA. THIS FRONT WILL
RE-DEVELOP AND STRENGTHEN LATER TONIGHT/EARLY THURSDAY AS THE
APPROACHING UPPER LEVEL ENERGY TRIGGERS CYCLOGENESIS ALONG THE GA/SC
COAST. RELATED MASS FIELDS WILL QUICKLY PUSH THIS SURFACE BOUNDARY
THROUGH OUR AREA LATE THURSDAY MORNING INTO THE AFTERNOON.
OVERALL...DOES NOT APPEAR THAT WE WILL SEE ENOUGH MOISTURE RETURN
FOR A WIDESPREAD OR SIGNIFICANT RAIN EVENT AHEAD OF THIS FRONT...
HOWEVER...THERE WILL BE ENOUGH DEEP LAYER QG FORCING/SYNOPTIC
SUPPORT ALONG WITH INCREASING SURFACE FOCUS ALONG THE LOW LEVEL
BOUNDARY TO SUPPORT AT LEAST A BROKEN BAND OF SHOWERS DURING THE
DAYLIGHT HOURS THURSDAY. IN GENERAL...LIKELY LOOKING AT AT AROUND
A TENTH OF AN INCH OR LESS QPF.
POSSIBLY MORE SIGNIFICANT IS THE WIND GUSTS POTENTIAL IN THE WAKE OF
THE FRONT...ESPECIALLY ALONG THE IMMEDIATE COAST. GFS/ECMWF ARE BOTH
SHOWING SUSTAINED WINDS OF 25-30 KNOTS OVER THE EASTERN GULF LATER
THURSDAY INTO THURSDAY EVENING. AT LEAST SOME OF THIS WIND ENERGY
WILL TRANSLATE TO THE COAST AND WOULD NOT BE SURPRISED TO SEE GUSTS
OVER 30 MPH IN CLOSE PROXIMITY TO THE WATER DURING THAT TIME. THE
STRONG ONSHORE FLOW WILL ALSO PUSH A DECENT WESTERLY SWELL TOWARD
THE BEACHES. LATEST FORECAST WOULD SUGGEST A HIGH SURF ADVISORY MAY
BE NEEDED FROM PINELLAS COUNTY SOUTHWARD THURSDAY EVENING THROUGH
FRIDAY MORNING.
COLD FRONT WILL CLEAR THE FORECAST AREA EARLY THURSDAY EVENING WITH
COOLER AND GENERALLY DRY WEATHER RETURNING FOR FRIDAY.
&&
.AVIATION...
SOME MVFR/LOCAL IFR CONDITIONS EARLY THIS MORNING WILL LIFT AND
DISSIPATE WITH VFR CONDITIONS THEN PREVAILING INTO EARLY TONIGHT.
LATE TONIGHT INTO EARLY THURSDAY MORNING THERE COULD BE SOME MORE
MVFR/LOCAL IFR CONDITIONS...BUT MAINLY AT LAL...PGD AND RSW.
&&
.MARINE...
FORECAST WATERS RESIDE BETWEEN A RIDGE OF HIGH PRESSURE TO OUR EAST
AND A FRONTAL BOUNDARY OVER THE CENTRAL GULF OF MEXICO. SOUTH TO
SOUTHEAST FLOW WILL CONTINUE AHEAD OF THIS FRONT THROUGH TONIGHT.
THE COLD FRONT WILL STRENGTHEN AND QUICKLY TRANSLATE THROUGH THE
EASTERN GULF OF MEXICO ON THURSDAY. WINDS WILL SHIFT WEST AND
NORTHWEST BEHIND THE FRONT AND QUICKLY INCREASE TO ADVISORY LEVELS.
A FEW WIND GUSTS TO NEAR GALE FORCE APPEAR POSSIBLE LATE THURSDAY
AFTERNOON INTO THURSDAY NIGHT...ALONG WITH SEAS BUILDING TO OVER 7
FEET AWAY FROM THE COAST. WINDS WILL VEER TO THE NORTHEAST ON
FRIDAY...BUT REMAIN ELEVATED ALONG WITH SEAS THROUGH THE DAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 79 64 70 47 / 0 10 50 10
FMY 83 64 79 51 / 0 10 30 10
GIF 81 63 74 44 / 0 10 30 10
SRQ 78 62 71 49 / 0 10 40 10
BKV 81 57 70 42 / 0 10 50 10
SPG 79 65 68 52 / 0 10 50 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/MARINE...MROCZKA
AVIATION...CLOSE
AREA FORECAST DISCUSSION
NWS DULUTH MN
551 AM CST WED JAN 16 2013
.AVIATION...12Z TAFS
IFR OR LOW MVFR CEILINGS COVERED MOST OF NORTHEAST
MINNESOTA EARLY THIS MORNING...WITH MVFR CEILINGS AND VSBYS FROM 1 TO 3
MILES IN SNOW OR FREEZING DRIZZLE WERE OCCURRING OVER NORTHWEST
WISCONSIN. MUCH OF THE PRECIPITATION WILL MOVE OUT OF THE
NORTHLAND THIS MORNING...AND CEILINGS WILL INCREASE TO MVFR. WE
FOLLOWED CLOSE TO THE RAP 925MB CONDENSATION PRESSURE DEFICITS TO
TIME CLEARING TODAY. GUSTY WEST TO NORTHWEST WINDS WILL OCCUR THIS
MORNING INTO EARLY AFTERNOON BEFORE DIMINISHING LATE.
&&
.PREV DISCUSSION... /ISSUED 408 AM CST WED JAN 16 2013/
SHORT TERM...TODAY THROUGH THURSDAY.
AT 4 AM...LIGHT SNOW CONTINUED TO SPREAD SOUTHEAST ACROSS THE CWA.
THE LOWEST VSBYS WERE NOW IN NW WI. THERE HAS ALSO BEEN SOME
PATCHY FREEZING DRIZZLE ACROSS THE AREA. TEMPERATURES WERE LARGELY
IN THE 20S.
THE MAIN FOCUS FOR THE MORNING WILL CONTINUE TO BE LIGHT SNOW AND
PATCHY FREEZING DRIZZLE. THE COMBINATION OF FREEZING DRIZZLE AND
SNOW WILL MAKE ROADS SLICK THIS MORNING. THE COLD FRONT WILL MOVE
QUICKLY SE ACROSS THE CWA THIS MORNING...FOLLOWED BY FALLING
TEMPERATURES DUE TO STRONG CAA BEHIND THE COLD FRONT. SW WINDS
WILL SWITCH TO THE NW AND BECOME GUSTY DURING THE AFTERNOON.
ARCTIC HIGH PRESSURE WILL BUILD ACROSS THE REGION TONIGHT...WITH
VERY COLD AIR SETTLING INTO THE NORTHLAND. HAVE DROPPED TEMPS EVEN
FURTHER FOR TONIGHT GIVEN THE STRENGTH OF THE ARCTIC AIR. EXPECT
TEMPERATURES TO FALL INTO THE MID 20S BELOW ZERO IN THE NORTH
TONIGHT. WITH WINDS SWITCHING TO THE NW...WE COULD ALSO SEE SOME
LAKE EFFECT SNOW SHOWERS ALONG THE SOUTH SHORE. NOT LOOKING FOR
TOO MUCH IN THE WAY OF SNOW ACCUMULATION AS WINDS WILL BE A BIT
WESTERLY.
ARCTIC HIGH PRESSURE WILL REINFORCE ITSELF ACROSS THE REGION ON
THURSDAY...WITH TEMPERATURES REMAINING BELOW ZERO ACROSS THE
NORTHERN THIRD OF THE CWA. ONCE THE CLOUDS SCOUR OUT THIS
AFTERNOON...WE SHOULD SEE A FAIR AMOUNT OF CLEAR SKIES TONIGHT
INTO THURSDAY.
LONG TERM...THURSDAY NIGHT THROUGH TUESDAY.
MAIN STORY IN THE EXTENDED WILL BE VERY COLD AIR MOVING OVER THE
REGION LATER IN THE WEEKEND...INTO THE MIDDLE OF NEXT WEEK.
UPPER RIDGE OVER THE WEST COAST/EASTERN PACIFIC WILL GRADUALLY SHIFT
OVER THE WESTERN CONUS LATE IN THE PERIOD. AN UPPER LOW OVER HUDSON
BAY WILL SHIFT EAST AND NORTH INTO THE WEEKEND...WITH SHORTWAVES
MOVING THROUGH AND MUCH COLDER AIR MOVING IN OVER THE WEEKEND.
A SHORTWAVE AND WAA WILL AFFECT THE CWA THURSDAY NIGHT LEADING TO A
CHANCE FOR LIGHT SNOW INTO FRIDAY. TEMPS SHOULD DROP QUICKLY
THURSDAY EVENING...THEN RISE OVERNIGHT WITH INCREASING CLOUDS/WAA.
GOOD WAA WILL LEAD TO ACCUMULATIONS FROM A DUSTING TO PERHAPS 2
INCHES. 850MB TEMPS ARE FORECAST TO RISE TO NEAR 0C ACROSS OUR
SOUTHWEST CWA ON FRIDAY...LEADING TO HIGHS IN THE UPPER TWENTIES TO
NEAR 30 IN OUR SOUTHERN ZONES.
ANOTHER WAVE AND SURFACE LOW WILL LEAD TO A CONTINUED CHANCE FOR
LIGHT SNOW FRIDAY NIGHT AND SATURDAY. THE WAVE ON SATURDAY IS
STRONGER...AND THE LATEST ECMWF SUGGESTS A FEW INCHES OF SNOW WILL
BE POSSIBLE...MAINLY OVER NORTHERN MINNESOTA. MUCH COLDER AIR WILL
POUR INTO THE NORTHLAND AS THE LOW PASSES ON SATURDAY. 850MB TEMPS
ARE FORECAST TO DROP TO -20 TO -22C OVER MUCH OF OUR MINNESOTA CWA
SATURDAY AFTERNOON...WITH EVEN COLDER TEMPS MOVING IN SUNDAY NIGHT.
A FAVORABLE PERIOD FOR SIGNIFICANT LES WILL OCCUR ALONG THE SOUTH
SHORE AS THE COLDER AIR MOVES IN SATURDAY AFTERNOON/NIGHT.
COLD WILL BE THE MAIN STORY SUNDAY INTO TUESDAY. LOWS SUNDAY NIGHT
INTO TUESDAY NIGHT WILL BE IN THE TEENS BELOW ZERO TO MID TWENTIES
BELOW. THERE WILL BE ENOUGH WIND SATURDAY NIGHT TO CREATE SOME VERY
LOW WIND CHILLS. HIGHS SUNDAY INTO TUESDAY ARE FORECAST TO REMAIN AT
OR BELOW ZERO OVER NORTHEAST MINNESOTA...AND ONLY BE A FEW DEGREES
WARMER OVER NORTHWEST WISCONSIN.
&&
.POINT TEMPS/POPS...
DLH 26 -14 4 -2 / 30 10 10 40
INL 19 -26 -4 -15 / 10 10 10 40
BRD 28 -12 9 4 / 20 10 10 40
HYR 30 -11 10 -2 / 60 10 10 40
ASX 30 -6 10 4 / 60 40 20 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...DAP
LONG TERM....MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
636 AM CST WED JAN 16 2013
.UPDATE...
UPDATED FOR A EASTWARD TREND OF -SN ACROSS THE LANGDON TO GFK TO
PARK RAPIDS LINE. ALSO COOLED TEMPS THIS MORNING ACROSS THE NORTH
AS TEMPS IN THE SINGLE DIGITS ENTERING INT EH NORTHERN VALLEY
ALREADY. LATEST RAP MODEL RUN HANDLED THESE TRENDS VERY WELL USED
IT FOR THE REST OF THE MORNING AND INTO EARLY AFTN OF PCPN
PLACEMENT.
&&
.PREV DISCUSSION... /ISSUED 340 AM CST WED JAN 16 2013/
SHORT TERM...
THE CHALLENGES FOR THE FORECAST THIS MORNING INCLUDE THE TIMING OF
FRONTAL PASSAGES AND ASSOCIATED PCPN/CLOUD COVER AND AND ITS
EFFECT ON TEMPERATURES. MODELS IN REASONABLE AGREEMENT WITH GENERAL
FEATURES THROUGH THE END OF THE WEEK AND WILL USE A BLEND FOR THE
FORECAST PACKAGE.
COLD FRONT CURRENTLY PUSHING ACROSS THE CWFA WITH A STRONG PUSH OF
CAA IN ITS WAKE. AHEAD OF THE WIND SHIFT TO THE NORTH TEMPS HAVE
PUSHED INTO THE MID 30S VALLEY AND WEST. SAFE TO SAY TODAYS HIGHS
HAVE BEEN REACHED AND TEMPS WILL FALL FOR THE REST OF THE DAY AS
925MB TEMPS DROP 10 TO 20 C BY 00Z THURS. SOME -SN IS LIKELY ACROSS
THE SW PORTION OF THE CWFA AS A WEAK IMPULSE MOVES SE ALONG THE
BAROCLINIC ZONE AND UNDER THE 300MB RIGHT EXIT REGION. EXPECT AN
INCH OR TWO ALONG AND SOUTH OF A LINE FROM DVL TO W CASS TO ELBOW
LAKE.
SFC HIGH PRESSURE SLIDES ACROSS THE REGION TONIGHT AND TEMPS WILL
BE HIGHLY DEPENDENT ON CLOUD COVER WITH THE COLDEST VALUES
EXPECTED ACROSS THE NW MN... NEAR ZERO IN THE FAR WEST TO ALMOST
20 BELOW IN THE N RRV AND ROX TO BDE AREAS. A SLOW RECOVERY
EXPECTED THURSDAY AS WEAK MIXING AND THE COLD COLUMN LIMIT
WARMING.
RETURN FLOW AHEAD OF THE NEXT SW IN THE NW FLOW BEGINS THURSDAY PM
AND SHOULD LIMIT TEMP DROP OFF ACROSS E ND AS CLOUDS/-SN IN THE
WAA MOVES INTO THE FA. SFC LOW TRACK ALONG AND SOUTH OF THE
INTERNATIONAL BORDER WILL KEEP BEST CHC FOR -SN ALONG THE
INTERNATIONAL BORDER AREAS TO BEMIDJI FRIDAY WITH WEST WINDS
ALLOWING FOR SOME WARMING ACROSS SE ND FRIDAY AFTN. COLD FRONT
PUSHES THROUGH OVERNIGHT WITH FALLING TEMPS EXPECTED DURING THE
DAY SATURDAY.
LONG TERM (SAT-TUE)... A COLD PERIOD COMING UP AS ALL LONG RANGE
MODELS SHOW THE POLAR LOW OVER HUDSON BAY. SEVERAL SHORT WAVES
WILL CONTINUE TO MOVE SOUTHEAST...ONE WILL MOVE THRU SUNDAY
FOLLOWED BY HIGH PRESSURE AND LIKELY THE COLDEST OF THE AIRMASSES
THIS WINTER SEASON FOR SUN NIGHT INTO TUESDAY. EXPECT TEMPS TO
REMAIN BLO ZERO SUN-TUE. WITH HIGH OVERHEAD AND LIKELY A CLEAR
SKY SHOULD HAVE WIDESPREAD -20S SUN NIGHT AND AGAIN MON
NIGHT...COLDEST IN THE NORTH AND EASTERN PARTS OF THE FCST AREA.
AVIATION...
CIGS SHOULD IMPROVE AS IFR/MVFR CONDITIONS ERODE WITH DRIER
NORTHERLY WINDS AT ALL TAF SITES. ANY STRONG GUSTS THIS MORNING
WILL DIMINISH DURING THE LATER HALF OF THE DAY WITH SFC HIGH
BUILDING IN TO THE REGION. SNOW BAND MAY CLIP THE DVL AND FAR TAF
SITES THROUGH EARLY AFTN... MAY CAUSE VSBY/CIGS TO DROP FOR A BRIEF
PERIOD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
939 AM EST WED JAN 16 2013
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL BUILD EAST INTO THE OHIO VALLEY
TODAY. FOR TONIGHT INTO THURSDAY...A WEAK COLD FRONT WILL PUSH
EAST ACROSS THE GREAT LAKES. HIGH PRESSURE WILL BUILD BACK INTO
THE REGION ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A WEAK RIDGE OF HIGH PRESSURE WILL BUILD EAST INTO THE OHIO VALLEY
TODAY. LOW LEVEL MOISTURE WILL SCOUR AND/OR SHIFT OFF TO THE EAST
AS DRIER AIR FILTERS INTO THE REGION FROM THE WEST. CLOUDS STILL
MAY BE SLOW TO CLEAR AS HIGH LEVEL MOISTURE LINGERS. WENT CLOSE
TO GUIDANCE FOR HIGHS THIS AFTERNOON WHICH SHOULD RANGE FROM THE
MID AND UPPER 30S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
A WEAK COLD FRONT WILL GLANCE THE NORTHEASTERN PARTS OF OUR AREA
TONIGHT INTO THURSDAY MORNING. SOME LIGHT PRECIPITATION WILL PASS
TO OUR NORTH AND IS NOT EXPECTED TO REACH OUR ZONES AT THIS TIME.
HIGH PRESSURE WILL THEN BEGIN TO BUILD ACROSS THE REGION LATER
ON THURSDAY. GRADUAL CLEARING IS EXPECTED TO OCCUR ON THURSDAY AS
WELL. CLEARING WILL EXTEND INTO THURSDAY NIGHT AS THE RIDGE
CONTINUES TO EXTEND ACROSS THE OHIO VALLEY. THIS WILL BRING SOME
FAVORABLE RADIATIONAL COOLING CONDITIONS THURSDAY NIGHT.
THEREFORE...WENT BELOW MODEL GUIDANCE FOR LOWS FOR THAT PARTICULAR
PERIOD.
THE RIDGE WILL THEN SLIDE SOUTH OF OUR AREA FRIDAY AND SETTLE
ACROSS THE SOUTHEASTERN ATLANTIC COAST BY SATURDAY. THIS WILL BRING
A TRANSITION TO RETURN FLOW WHICH IN TURN WILL BRING ABOUT A
GRADUAL WARMING TREND FROM FRIDAY THROUGH SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
MUCH COOLER AIR IS IN STORE FOR THE REMAINDER OF THE LONG TERM
TIME FRAME. AN UPPER LEVEL DISTURBANCE WILL MOVE THROUGH THE FA
SATURDAY NIGHT BRINGING A CHANCE FOR SNOW SHOWERS TO NORTHERN
PORTIONS OF THE FA. COOLER AIR WILL BE USHERED INTO THE AREA
SATURDAY NIGHT WITH LOWS DROPPING INTO THE 20S BY SUNDAY MORNING.
NOT EXPECTING MUCH IN THE WAY OF AN INCREASE IN TEMPERATURES ON
SUNDAY AS COLDER AIR CONTINUES TO FILTER INTO THE AREA.
THE NEXT DISTURBANCE WILL WORK INTO THE AREA MONDAY INTO MONDAY
NIGHT ALLOWING FOR A BETTER CHANCE OF SOME SNOW SHOWERS AND A
REINFORCING SHOT OF COLD AIR. WITH COOLER AIR WORKING INTO THE AREA
AND WITH CLOUD COVER EXPECT HIGH TEMPERATURES ON MONDAY ONLY TO
REACH INTO THE UPPER TEENS TO MIDDLE 20S. THE TEMPERATURES WILL
DROP OFF INTO THE UPPER SINGLE DIGITS TO THE LOW TEENS MONDAY
NIGHT. CLOUD COVER ACROSS THE AREA WILL KEEP TEMPERATURES FROM
DROPPING EVEN FURTHER. WITH WINDS OFF OF THE LAKE SOME LAKE EFFECT
SNOW SHOWERS MAY LINGER THROUGH THE DAY ON TUESDAY BEFORE DRY
CONDITIONS RETURN TO THE REGION TUESDAY NIGHT. EXPECT THE COLDEST
NIGHT TO BE TUESDAY NIGHT WITH LESS CLOUD COVER ACROSS THE AREA.
WIDESPREAD SINGLE DIGIT TEMPERATURES WILL BE POSSIBLE TUESDAY NIGHT.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
PCPN HAS PUSHED WELL SOUTHEAST OF THE TAF SITES THIS MORNING. MAIN
CONCERN IS SOME LINGERING MVFR CIGS THAT EXTEND BACK INTO PARTS
OF EASTERN INDIANA. THE LATEST RAP IS ACTUALLY TRYING TO CLEAR
THESE LOWER CLOUDS OUT THROUGH LATE MORNING AS LOW LEVEL FLOW
BECOMES NORTHWESTERLY. WILL TREND THE FORECAST ACCORDINGLY AND
ALLOW FOR CLOUDS TO START TO SCATTER OUT THROUGH MID DAY. HIGH
PRESSURE AND A DRIER AIRMASS WILL THEN SETTLE INTO THE REGION
THROUGH THIS AFTERNOON. A WEAKENING BOUNDARY WILL PUSH DOWN FROM
THE NORTHWEST LATER TONIGHT. THIS COULD LEAD TO AN INCREASE IN
MAINLY VFR CIGS LATE IN THE PERIOD.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HICKMAN/LATTO
NEAR TERM...HICKMAN/LATTO
SHORT TERM...LATTO/HICKMAN
LONG TERM...NOVAK
AVIATION...JGL
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
632 AM EST WED JAN 16 2013
.SYNOPSIS...
LOW PRESSURE WILL EXIT THE REGION TODAY. HIGH PRESSURE WILL
GRADUALLY BUILD ACROSS THE AREA STARTING THURSDAY. THIS WILL
BRING A PERIOD OF QUIET WEATHER THROUGH THE START OF THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOW PRESSURE LOCATED OVER THE CENTRAL APPALACHIANS WILL CONTINUE
ITS NORTHEASTWARD TRACK TOWARD THE NEW ENGLAND COAST TODAY. THE
BACK EDGE OF A WINTRY MIX OF PRECIPITATION WILL EXIT THE
SOUTHEASTERN PORTIONS OF THE FORECAST AREA BY MID MORNING. HAVE
CANCELLED THE WINTER WEATHER ADVISORY FOR ALL OTHER ZONES EXCEPT
THOSE WITH ONGOING PRECIPITATION. CLOUD COVER EXTENDING FROM THE
EAST COAST WESTWARD TO ILLINOIS WILL TAKE ITS TIME DEPARTING OUR
AREA TODAY. EVENTUALLY...SOME BREAKS TO OUR NORTHWEST WILL TRY TO
MAKE IT INTO THE NORTHERN PARTS OF THE FORECAST AREA THIS
AFTERNOON. HOWEVER...THIS WILL BE SHORT LIVED AS CLOUD COVER WILL
ONCE AGAIN INCREASE AS A COLD FRONT APPROACHES FROM THE NORTH THIS
EVENING.
HIGH TEMPERATURES WILL REMAIN IN CHECK TODAY WITH CLOUD COVER
PERSISTING FOR MUCH OF THE AREA. WENT CLOSE TO GUIDANCE FOR HIGHS.
HOWEVER...AS THE PAST FEW DAYS HAVE SHOWN...THESE NUMBERS MAY BE
TOO HIGH IF WE DO NOT SEE MUCH OF THE WAY OF ANY SUN TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
THE COLD FRONT WILL GLANCE THE NORTHEASTERN PARTS OF OUR AREA
WEDNESDAY LATE NIGHT. SOME LIGHT PRECIPITATION WILL PASS TO OUR
NORTH AND IS NOT EXPECTED TO REACH OUR ZONES AT THIS TIME.
HIGH PRESSURE WILL THEN BEGIN TO BUILD ACROSS THE REGION ON
THURSDAY. GRADUAL CLEARING IS EXPECTED TO OCCUR ON THURSDAY AS
WELL. CLEARING WILL EXTEND INTO THURSDAY NIGHT AS THE RIDGE
CONTINUES TO EXTEND ACROSS THE OHIO VALLEY. THIS WILL BRING SOME
FAVORABLE RADIATIONAL COOLING CONDITIONS THURSDAY NIGHT.
THEREFORE...WENT BELOW MODEL GUIDANCE FOR LOWS FOR THAT PARTICULAR
PERIOD.
THE RIDGE WILL THEN SLIDE SOUTH OF OUR AREA FRIDAY AND SETTLE
ACROSS THE SOUTHEASTERN ATLANTIC COAST BY SATURDAY. THIS WILL BRING
A TRANSITION TO RETURN FLOW WHICH IN TURN WILL BRING ABOUT A
GRADUAL WARMING TREND FROM FRIDAY THROUGH SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
MUCH COOLER AIR IS IN STORE FOR THE REMAINDER OF THE LONG TERM
TIME FRAME. AN UPPER LEVEL DISTURBANCE WILL MOVE THROUGH THE FA
SATURDAY NIGHT BRINGING A CHANCE FOR SNOW SHOWERS TO NORTHERN
PORTIONS OF THE FA. COOLER AIR WILL BE USHERED INTO THE AREA
SATURDAY NIGHT WITH LOWS DROPPING INTO THE 20S BY SUNDAY MORNING.
NOT EXPECTING MUCH IN THE WAY OF AN INCREASE IN TEMPERATURES ON
SUNDAY AS COLDER AIR CONTINUES TO FILTER INTO THE AREA.
THE NEXT DISTURBANCE WILL WORK INTO THE AREA MONDAY INTO MONDAY
NIGHT ALLOWING FOR A BETTER CHANCE OF SOME SNOW SHOWERS AND A
REINFORCING SHOT OF COLD AIR. WITH COOLER AIR WORKING INTO THE AREA
AND WITH CLOUD COVER EXPECT HIGH TEMPERATURES ON MONDAY ONLY TO
REACH INTO THE UPPER TEENS TO MIDDLE 20S. THE TEMPERATURES WILL
DROP OFF INTO THE UPPER SINGLE DIGITS TO THE LOW TEENS MONDAY
NIGHT. CLOUD COVER ACROSS THE AREA WILL KEEP TEMPERATURES FROM
DROPPING EVEN FURTHER. WITH WINDS OFF OF THE LAKE SOME LAKE EFFECT
SNOW SHOWERS MAY LINGER THROUGH THE DAY ON TUESDAY BEFORE DRY
CONDITIONS RETURN TO THE REGION TUESDAY NIGHT. EXPECT THE COLDEST
NIGHT TO BE TUESDAY NIGHT WITH LESS CLOUD COVER ACROSS THE AREA.
WIDESPREAD SINGLE DIGIT TEMPERATURES WILL BE POSSIBLE TUESDAY NIGHT.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
PCPN HAS PUSHED WELL SOUTHEAST OF THE TAF SITES THIS MORNING. MAIN
CONCERN IS SOME LINGERING MVFR CIGS THAT EXTEND BACK INTO PARTS
OF EASTERN INDIANA. THE LATEST RAP IS ACTUALLY TRYING TO CLEAR
THESE LOWER CLOUDS OUT THROUGH LATE MORNING AS LOW LEVEL FLOW
BECOMES NORTHWESTERLY. WILL TREND THE FORECAST ACCORDINGLY AND
ALLOW FOR CLOUDS TO START TO SCATTER OUT THROUGH MID DAY. HIGH
PRESSURE AND A DRIER AIRMASS WILL THEN SETTLE INTO THE REGION
THROUGH THIS AFTERNOON. A WEAKENING BOUNDARY WILL PUSH DOWN FROM
THE NORTHWEST LATER TONIGHT. THIS COULD LEAD TO AN INCREASE IN
MAINLY VFR CIGS LATE IN THE PERIOD.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...LATTO
NEAR TERM...LATTO
SHORT TERM...LATTO
LONG TERM...NOVAK
AVIATION...JGL
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
521 AM CST WED JAN 16 2013
.SHORT TERM...TODAY THROUGH FRIDAY
355 AM CST WED JAN 16 2013
AT 3 AM...A SHORT WAVE TROUGH WAS MOVING SOUTHEAST ACROSS THE
NORTHERN TWO-THIRDS OF MINNESOTA AND NORTHWEST WISCONSIN. AREAS OF
SNOW IS BEING REPORTED ACROSS MINNESOTA AND EASTERN SOUTH DAKOTA.
THE 280-290K ISENTROPIC SURFACES SHOW THAT ONLY 10 MB OF LIFT WILL
BE NEEDED FOR SATURATION TO OCCUR. NEITHER THE NAM/WRF OR THE GFS
IS THAT IMPRESSIVE WITH THEIR OMEGA IN THE BUFKIT SOUNDINGS.
MEANWHILE THE RAP SHOWS THAT THERE WILL BE 5 TO 10 MICROBARS OF
LIFT. IN ADDITION...THE MESO MODELS SHOW THAT SOME LIGHT SNOW WILL
FALL ACROSS THE AREA. AREAS SOUTH OF THE INTERSTATE 94 CORRIDOR
WILL LIKELY ONLY SEE A DUSTING OF SNOW...SO KEPT PRECIPITATION
PROBABILITIES IN THE 20 TO 40 PERCENT RANGE. MEANWHILE NORTH OF
THIS AREA...THERE IS DEEPER MOISTURE AND STRONGER FORCING...SO
WENT WITH 50 TO 80 PERCENT PRECIPITATION PROBABILITIES. SNOWFALL
AMOUNTS IN THESE AREAS LOOK TO BE AROUND A HALF INCH.
DESPITE CLOUDS ACROSS THE AREA TODAY...TEMPERATURES WILL WARM
INTO THE 30S ACROSS THE AREA. LIKE THE PAST COUPLE OF THE
DAYS...THE NAM/WRF WAS INITIALIZED WITH WAY TOO MUCH SNOW COVER
ACROSS WISCONSIN /2 TO 8 INCHES/ AND EAST CENTRAL MINNESOTA /5 TO
8 INCHES/. SINCE THE MODEL IS TRYING TO MELT THIS SNOW...ITS
TEMPERATURES ARE TOO COLD...SO WENT WITH THE WARMER GFS AND ECMWF.
FOR THIS AFTERNOON AND EVENING...THE MODELS ARE SHOWING THAT THE
SECOND SHORT WAVE TROUGH IS MUCH WEAKER. AS A RESULT...THERE WILL
LIKELY NOT BE ENOUGH MOISTURE OF LIFT FOR ANOTHER ROUND OF SNOW TO
DEVELOP. LOOKING UPSTREAM...THERE IS NO PRECIPITATION ASSOCIATED
WITH THIS WAVE...THUS...TOOK OUT THE MENTION FOR PRECIPITATION.
FOR TONIGHT...A COLD FRONT WILL MOVE SOUTH THROUGH THE AREA. LOW
TEMPERATURES ON TUESDAY MORNING WILL RANGE 0 TO 15 DEGREES. THIS
IS CLOSE TO WHAT WE NORMALLY SEE IN MID-JANUARY.
ON THURSDAY NIGHT...THE MODELS CONTINUE TO SHOW THAT A WARM FRONT
WILL MOVE NORTH ACROSS THE AREA. THE GFS...GEM...AND ECMWF ARE IN
GOOD AGREEMENT THAT THERE WILL BE ENOUGH MOISTURE AND LIFT FOR
SOME LIGHT SNOW TO DEVELOP ALONG AND NORTH OF THE INTERSTATE 94
CORRIDOR. SNOWFALL AMOUNTS LOOK LIKE THEY WILL BE A HALF INCH OR
LESS.
ON FRIDAY...A LOW PRESSURE SYSTEM WILL MOVE ACROSS NORTHERN
MINNESOTA AND NORTHERN WISCONSIN. STRONG SOUTHWEST WINDS ALOFT
WILL BRING WARM AIR QUICKLY INTO THE REGION. IN ADDITION...THE
CLOUDS WILL DECREASING DURING THE DAY/ THE COMBINATION OF
SOUTHWEST WINDS...SUNSHINE...AND NO SNOW COVER...TEMPERATURES
SHOULD EASILY CLIMB INTO THE 30S AND LOWER 40S. IF THE ECMWF IS
CORRECT...THE TEMPERATURES MAY BE EVEN A COUPLE MORE DEGREES
WARMER. IT HAS BEEN SHOWING HIGHS IN THE LOWER AND MID 40S FOR THE
PAST 4 NIGHTS. AS STATED IN EARLIER...THE NAM/WRF HAS WAY TOO MUCH
SNOW ACROSS WISCONSIN...THUS...THREW OUT ITS MOS GUIDANCE.
.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
355 AM CST WED JAN 16 2013
ON FRIDAY NIGHT...A COLD FRONT WILL BRIEFLY SURGE SOUTHWARD INTO
THE AREA AND THEN MOVE BACK NORTH AS A WARM FRONT AS A LOW
PRESSURE SYSTEM MOVES INTO NORTHWEST MINNESOTA. THE 275-285K
ISENTROPIC SURFACES SHOW THAT IT WILL TAKE 50 TO 100 MB FOR
SATURATION TO OCCUR. AS A RESULT...KEPT THE FORECAST DRY FOR NOW.
HIGH TEMPERATURES ON SATURDAY WILL RANGE FROM THE MID 20S TO MID 30S.
FROM LATE SATURDAY AFTERNOON INTO SATURDAY NIGHT...AN ARCTIC COLD
FRONT WILL MOVE SOUTH THROUGH THE FORECAST AREA. THE BEST MOISTURE
AND LIFT LOOKS TO BE MAINLY ALONG AND NORTH OF THE INTERSTATE 94
CORRIDOR. DUE TO THIS...KEPT LIGHT SNOW CHANCES MAINLY CONFINED
TO THIS AREA. LIKE LAST NIGHT...THE MODEL SOUNDINGS CONTINUE TO
SUGGEST THAT THE WINDS MAY BRIEFLY GUST INTO THE 35 TO 45 MPH
RANGE IN THE WAKE OF THIS FRONT.
ON SUNDAY NIGHT AND MONDAY MORNING...THE MODELS CONTINUE TO SHOW
THAT ANOTHER ARCTIC COLD FRONT WILL MOVE SOUTH THROUGH THE REGION.
THE GEM...GFS...AND ECMWF SUGGEST THAT SOME LIGHT SNOW WILL BE
ASSOCIATED WITH THIS FRONTAL PASSAGE. 850 MB TEMPERATURES ARE
AROUND 1.5 STANDARD DEVIATIONS BELOW NORMAL IN THE GFS AND AROUND
2 STANDARD DEVIATIONS BELOW NORMAL IN THE ECMWF. IT LOOKS LIKE
MUCH OF THE AREA WILL SEE HIGH TEMPERATURES REMAINING IN THE
SINGLE DIGITS. WIND CHILLS ON THIS MORNING LOOK TO BE IN THE 10 TO
20 BELOW RANGE.
ON MONDAY NIGHT...THE MODELS CONTINUE TO SHOW THAT LOW TEMPERATURES
WILL LIKELY RANGE FROM 5 TO 20 BELOW. WITH TEMPERATURES THIS COLD...
ANY WIND AT ALL WILL PRODUCE WIND CHILLS IN THE ADVISORY CRITERIA
/20 TO 35 BELOW/.
EARLY NEXT WEEK...THE MODELS CONTINUE TO SHOW THAT A STRONG SUDDEN
STRATOSPHERIC WARMING EVENT WILL TAKE PLACE ACROSS THE NORTH
CENTRAL PACIFIC. THIS WILL RESULT IN A LONG WAVE TROUGH QUICKLY
DEVELOPING ACROSS THIS AREA. THIS IS TURN WILL GIVE AN EASTERN
NUDGE TO THE LONG WAVE RIDGE ACROSS THE EAST PACIFIC AND WESTERN
NORTH AMERICA. AS THIS OCCURS...THE COLDEST AIR SHOULD START TO
SHIFT OUT OF THE AREA ON TUESDAY AND TUESDAY NIGHT. BOTH THE
DETERMINISTIC AND ENSEMBLE MEMBERS SHOW THIS OCCURRING...SO
CONFIDENCE IS FAIRLY HIGH THAT THIS LATEST BOUT OF ARCTIC AIR WILL
BE A SHORT LIVED.
&&
.AVIATION...TODAY AND TONIGHT
521 AM CST WED JAN 16 2013
SOUTHWEST FLOW AHEAD OF THE SYSTEM MOVING INTO THE UPPER MIDWEST
IS STILL PRODUCING SOME WIND SHEAR AT KLSE. EXPECT THIS WILL
DISSIPATE BY MID MORNING AS A SURFACE TROUGH APPROACHES AND THE
WINDS ALOFT DECREASE AHEAD OF THIS FEATURE. CLOUDS AHEAD OF THE
SURFACE TROUGH INITIALLY START OUT VFR BUT THEN LOWER TO MVFR AS
IT GETS CLOSER. THE LIGHT SNOW THAT HAD BEEN ALONG THE SURFACE
TROUGH OVER SOUTH DAKOTA AND WESTERN MINNESOTA HAS
WEAKENED/DISSIPATED WITH JUST SOME FLURRIES LEFT. THE MAIN AREA OF
VISIBILITY REDUCING SNOW WILL PASS TO THE NORTH OF BOTH TAF SITES
CLOSER TO THE MAIN SURFACE LOW MOVING ACROSS SOUTHERN ONTARIO AND
LAKE SUPERIOR. THE WINDS WILL SWITCH TO THE WEST BEHIND THE
SURFACE TROUGH AND SWING AROUND TO THE NORTHWEST LATE THIS
AFTERNOON OR EARLY EVENING ONCE THE COLD FRONT GOES THROUGH. THE
MVFR CEILINGS SHOULD REMAIN IN PLACE BEHIND THE SURFACE TROUGH BUT
HOW LONG THEY HOLD ON BEHIND THE COLD FRONT IS UNKNOWN. CEILINGS
ARE PRIMARILY MVFR BACK ACROSS NORTH DAKOTA INTO MANITOBA AND
ALBERTA BUT THERE ARE SOME AREAS OF VFR AS WELL. FORECAST
SOUNDINGS FROM THE 16.06Z NAM SUGGESTS THAT DRIER AIR WILL MOVE IN
THIS EVENING AND ACTUALLY CLEAR SKIES OUT. HOWEVER...NOT CONFIDENT
ON THIS AS THE MODEL SHOWS DRY AIR CURRENTLY NEAR LAKE
WINNIPEG...WHERE SKIES ARE CLEAR...BUT MOVES THIS ACROSS THE GREAT
LAKES AND NOT OVER THE AREA THIS EVENING. WILL STAY PESSIMISTIC
AND KEEP CEILINGS MVFR UNTIL CLOUDS TRENDS BECOME MORE WELL
DEFINED.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
355 AM CST WED JAN 16 2013
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...04
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1002 AM MST WED JAN 16 2013
.UPDATE...
&&
.SHORT TERM...CURRENT FORECASTS LOOKING ON TRACK. UPPER RIDGE TO
BEGIN BUILDING OVER THE REGION WITH NORTHWEST FLOW ALOFT. AIRMASS
TO BE MUCH WARMER WITH RAP SHOWING 700 TEMPS AROUND MINUS 4
CELSIUS BY 00Z. WITH MAINLY CLEAR SKIES EXPECTED...TEMPERATURES
SHOULD REBOUND TO NEAR NORMAL VALUES. BUT COLD AIR WILL REMAIN
TRAPPED IN MOUNTAIN VALLEYS WHICH WILL LIMIT THE WARMUP. ACROSS
PLAINS...THERE IS SOME SNOW COVER IN SPOTS WHICH WILL HINDER
WARMUP. CURRENT TEMPERATURES ARE SLOW TO WARM...AS LOW LEVEL
INVERSION REMAINS. FORECAST MAX TEMPERATURES SEEM REASONABLE FOR
NOW...THINKING THE INVERSION WILL BE BREAKING. WILL CONTINUE TO
MONITOR.
.AVIATION...LATEST MODELS INDICATING SOME SORT OF A NORTHEAST
COMPONENT AT THE AREA AIRPORTS THIS AFTERNOON...WITH PERHAPS THE
DEVELOPMENT OF AN ANTICYCLONE NORTH OF DENVER. CURRENT THINKING OF
A COUNTERCLOCKWISE TREND IN THE WINDS LOOKING MORE REASONABLE AND
WILL ADJUST WITH THE UPCOMING ISSUANCE. REST OF TAF TRENDS LOOK
GOOD.
&&
.PREV DISCUSSION... /ISSUED 405 AM MST WED JAN 16 2013/
SHORT TERM...TEMPERATURES HAVE REMAINED QUITE MILD OVERNIGHT
THANKS TO CLOUD COVER. BREEZY CONDITIONS WERE ALSO NOTED OVER THE
NORTHEAST PLAINS...AIDING MIXING. AS A RESULT...INVERSIONS ARE
QUITE WEAK THIS MORNING. FURTHER WARM ADVECTION WILL OCCUR THROUGH
THE DAY...AND SUNSHINE WILL RETURN IN EARNEST AS AIRMASS DRIES.
THERE WAS STILL SOME MID/HIGH LEVEL CLOUD COVER TO OUR NORTH...BUT
THIS WILL GRADUALLY THIN AND SEE LITTLE CHANCE OF MOUNTAIN WAVE
ENHANCEMENT WITH SUCH NORTHERLY FLOW. WRF AND NAM SYNTHETIC
SATELLITE IMAGERY ALSO SUPPORTS MAINLY SUNNY SKIES AFTER A FEW
EARLY MORNING CLOUDS. OVERALL...THIS SUPPORTS TEMPERATURES CLOSER
TO WARMER GFS MOS GUIDANCE. HOWEVER...THERE ARE SOME AREAS OF 1-4
INCH SNOW COVER ON THE PLAINS SO WILL HOLD THOSE LOCATIONS BACK
ABOUT 10 DEGREES.
FOR TONIGHT...CLEAR SKIES AND LIGHTER WINDS WILL ALLOW STRONGER
INVERSIONS TO REESTABLISH THEMSELVES. DESPITE THEIR BRIEF RESPITE
TODAY THANKS TO THE MILD START...HIGH MOUNTAIN VALLEYS WILL LIKELY
SETTLE BACK INTO COLDER TEMPERATURES DUE TO AMPLE SNOW COVER
THERE. OTHERWISE EXPECT MIN TEMPS NEAR NORMALS.
LONG TERM...SYNOPTIC SCALE MODELS ARE IN STRONG AGREEMENT THAT
THE NEXT WEEK IS GOING TO BE DOMINATED BY A STABLE AND PERSISTENT
RIDGE/TROUGH PATTERN ACROSS THE UNITED STATES. THIS WILL LEAVE
COLORADO UNDER DRY AND MILD NORTHWESTERLY FLOW ALOFT AND
PERSISTENT SUBSIDENT FORCING. CHANCES FOR PRECIPITATION WILL
ESSENTIALLY BE NIL THROUGH THE FORECAST PERIOD. TEMPERATURES WILL
MODERATE THROUGH THE WEEKEND...MORESO ON THE PLAINS THAN IN THE
MOUNTAIN VALLEYS. COLD AIR TRAPPED IN NORTH AND MIDDLE PARKS WILL
BE HARD TO SCOUR OUT. THERE WILL BE A BRIEF INTRUSION OF COLD AIR
INTO NORTHEAST COLORADO AS AN ALBERTA CLIPPER-LIKE SHORTWAVE
RACES THROUGH THE NORTHWEST FLOW THAT WILL BE IN PLACE. AT THIS
TIME THE INTRUSION OF COLD AIR LOOKS LIKE IT WILL BE QUITE SHALLOW
WITH LITTLE IMPACT ON THE AMOUNT OF MOISTURE OVER THE STATE.
TEMPERATURES WILL BE MUCH COOLER FOR THE MARTIN LUTHER KING
HOLIDAY...BUT THEN THEY ARE EXPECTED TO REBOUND NICELY FOR NEXT
TUESDAY AND WEDNESDAY AS THE WESTERN U.S. UPPER RIDGE AMPLIFIES
FOR A COUPLE DAYS. PRESENT INDICATIONS FROM THE ECMWF AND GFS
MODELS ARE THAT THE RIDGE/TROUGH PATTERN REMAINS IN PLACE THROUGH
NEXT WEDNESDAY BEFORE A TROUGH BEGINS MOVING INTO THE PACIFIC
NORTHWEST AND BEGINS BREAKING DOWN THE UPPER RIDGE LATE NEXT WEEK.
AVIATION...VISUAL LANDING CONDITIONS WILL PERSIST. WIND DIRECTION
WILL START OFF SOUTHWESTERLY AROUND 10 KTS...THEN SHOULD GRADUALLY
SHIFT MORE SOUTH/SOUTHEAST BY 16Z-18Z. WINDS THIS AFTERNOON WILL
BE MORE DIFFICULT DUE TO POSSIBLE INTERACTION WITH SNOW COVER OR
ANTICYCLONE...OR A COMBINATION OF THESE. FOR NOW...WILL OPT TOWARD
AN EAST/SOUTHEAST COMPONENT BUT SOME THREAT OF NORTHERLY WINDS UP
TO 10 KTS WILL BE POSSIBLE AT KDEN FROM 19Z-02Z. AFTER 02Z...
NORMAL SOUTH/SOUTHWEST WINDS 7-12 KTS WILL OCCUR.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....DANKERS
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
150 PM EST WED JAN 16 2013
...COLD FRONT ON THURSDAY ENDS THE STRETCH OF ABOVE NORMAL TEMPS...
...GALE WATCH IN EFFECT FOR PORTIONS OF THE COASTAL WATERS...
.SHORT TERM (THIS EVENING THROUGH FRIDAY NIGHT)...
18Z WATER VAPOR AND H4 RAP ANALYSIS SHOW A CONTINUED AMPLIFIED UPPER
LEVEL PATTERN OVER THE CONUS THIS WEDNESDAY MORNING. MAIN LONGWAVE
TROUGH AXIS OVER THE CENTRAL PORTION OF THE COUNTY IS UNDERGOING A
FRACTURE EVENT...WITH NORTHERN ENERGY LOBE CROSSING THE GREAT LAKES
REGION AND SOUTHERN VORTICITY CENTER CUTTING OFF OVER
CENTRAL/EASTERN TEXAS. THIS SOUTHERN ENERGY WILL BE PROGRESSIVE...
AND IS FORECAST TO BECOME QUITE A POTENT LITTLE UPPER LOW AS IT
MOVES ALONG THE NORTHERN GULF COAST THE NEXT 24-30 HOURS.
CLOSER TO HOME...THE PENINSULA IS EXPERIENCING ITS FINALLY DAY
UNDER THE SUPPRESSION OF THE UPPER RIDGE. THIS RIDGE HAS PROVIDED A
LONG DURATION OF DRY AND UNSEASONABLY WARM WEATHER FOR OVER A WEEK.
THE STRONG SYSTEM APPROACHING FORM THE WEST WILL COMPLETELY BREAK
DOWN THE RIDGE BY THIS TIME TOMORROW AND BRING COOLER AND MORE
SEASONABLE CONDITIONS FOR THE END OF THE WEEK.
AT THE SURFACE...HIGH PRESSURE CENTERED NORTH OF THE BAHAMAS
CONTINUES TO RIDGE BACK TO THE WEST INTO THE EASTERN GULF OF MEXICO.
FURTHER WEST WE FIND A CURRENTLY QUASI-STATIONARY FRONTAL BOUNDARY
EXTENDING FROM THE CENTRAL GULF NORTHWARD TO AL/GA. THIS FRONT WILL
RE-DEVELOP AND STRENGTHEN LATER TONIGHT/EARLY THURSDAY AS THE
APPROACHING UPPER LEVEL ENERGY TRIGGERS CYCLOGENESIS ALONG THE GA/SC
COAST. RELATED MASS FIELDS WILL QUICKLY PUSH THIS SURFACE BOUNDARY
THROUGH OUR AREA LATE THURSDAY MORNING INTO THE AFTERNOON.
OVERALL...DOES NOT APPEAR THAT WE WILL SEE ENOUGH MOISTURE RETURN
FOR A WIDESPREAD OR SIGNIFICANT RAIN EVENT AHEAD OF THIS FRONT...
HOWEVER...THERE WILL BE ENOUGH DEEP LAYER QG FORCING/SYNOPTIC
SUPPORT ALONG WITH INCREASING SURFACE FOCUS ALONG THE LOW LEVEL
BOUNDARY TO SUPPORT AT LEAST A BROKEN BAND OF SHOWERS DURING THE
DAYLIGHT HOURS. 12Z GUIDANCE CONTINUES TO INDICATE LOW QPF OF
GENERALLY A TENTH OF AN INCH OR LESS.
POSSIBLY MORE SIGNIFICANT IS THE WIND GUSTS POTENTIAL IN THE WAKE OF
THE FRONT...ESPECIALLY ALONG THE IMMEDIATE COAST. GFS/ECMWF ARE BOTH
SHOWING SUSTAINED WINDS OF 25-30 KNOTS OVER THE EASTERN GULF LATER
THURSDAY INTO THURSDAY EVENING. AT LEAST SOME OF THIS WIND ENERGY
WILL TRANSLATE TO THE COAST...AND WOULD NOT BE SURPRISED TO SEE
GUSTS OVER 30 MPH IN CLOSE PROXIMITY TO THE WATER DURING THAT TIME.
THE STRONG ONSHORE FLOW WILL ALSO PUSH A DECENT WESTERLY SWELL
TOWARD THE BEACHES. LATEST FORECAST SUGGEST A HIGH SURF ADVISORY
WILL BECOME NECESSARY FROM PINELLAS COUNTY SOUTHWARD ALONG THE
SUNCOAST THURSDAY EVENING THROUGH FRIDAY MORNING. THIS HIGH SURF AND
ONSHORE FLOW WILL ALSO SUPPORT AN ELEVATED RISK OF RIP CURRENTS LATE
THURSDAY AFTERNOON INTO FRIDAY.
COLD FRONT WILL CLEAR THE FORECAST AREA EARLY THURSDAY EVENING WITH
A COOLER AND DRIER AIRMASS ARRIVING ON GUSTY NORTHWEST/NORTH FLOW.
HIGH TEMPERATURES FOR MANY LOCATIONS ON THURSDAY ARE LIKELY TO OCCUR
DURING THE LATE MORNING OR MIDDAY AND THEN HOLD STEADY...OR EVEN
DROP THROUGH THE AFTERNOON HOURS IN THE POST-FRONTAL ENVIRONMENT.
THURSDAY NIGHT WILL FEEL COLD COMPARED TO WHAT THIS REGION HAS
EXPERIENCED LATELY. GENERALLY SPEAKING THE MOS IS TOO COLD ON THESE
EARLY ADVECTION NIGHTS AND HAVE RAISED THE MAV/MET CONSENSUS UP A
FEW DEGREES. EVEN STILL...WIDESPREAD 40S ARE EXPECTED...WITH EVEN
SOME UPPER 30S TOWARD LEVY COUNTY. ADD IN A LITTLE WIND...AND IT
WILL BE A CHILLY OVERNIGHT PERIOD.
SENSIBLE WEATHER FOR FRIDAY AND FRIDAY NIGHT WILL BE FAIR AS TEMPS
WILL BE BACK TO SEASONABLE LEVELS. ONCE AGAIN...RAISED THE MOS LOW
TEMPS A COUPLE DEGREES...ESPECIALLY OVER THE NATURE COAST ZONES DUE
TO AN UNFAVORABLE SURFACE RIDGE POSITION FOR SIGNIFICANT RADIATIONAL
COOLING.
&&
.LONG TERM (SATURDAY - TUESDAY)...
U/L RIDGE WILL PERSIST ALONG THE WEST COAST OF THE U.S. WITH A BROAD
TROUGH ACROSS THE REMAINDER OF THE CONUS. SURFACE HIGH PRESSURE
WILL HOLD OVER THE SOUTHEAST U.S. FRIDAY NIGHT AND SATURDAY WITH A
STATIONARY BOUNDARY SOUTH OF THE FORECAST AREA. BROAD EAST TO
NORTHEAST FLOW OFF THE ATLANTIC COMBINED WITH WARM AIR OVERRUNNING
THE COLDER AIR ACROSS WEST CENTRAL AND SOUTHWEST FLORIDA WILL CREATE
MOSTLY CLOUDY SKIES AND A FEW SPRINKLES OVER THE REGION. SURFACE
HIGH PRESSURE WILL HOLD OVER THE REGION SUNDAY WITH BOUNDARY LAYER
FLOW BACKING TO THE NORTH AND NORTHWEST ON MONDAY AS A REINFORCING
COLD FRONT MOVES ACROSS THE REGION. LITTLE DEEP LAYER MOISTURE OR
U/L SUPPORT TO WORK WITH SO ONLY EXPECT MOSTLY CLOUDY SKIES AS THE
FRONT PUSHES ACROSS THE AREA. MUCH COOLER DRIER AIR WILL ADVECT
ACROSS THE FORECAST AREA MONDAY NIGHT AND TUESDAY WITH CLEARING
SKIES AND BREEZY NORTH TO NORTHWEST WINDS.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL THROUGH EARLY TONIGHT. AFTER ABOUT 08Z
TONIGHT SOME AREAS OF MVFR/LOCAL IFR CEILINGS WILL BE POSSIBLE AT
ALL TERMINALS WITH SOME MVFR/IFR VISIBILITIES AT LAL...PGD AND RSW.
SCATTERED SHOWERS WILL BE POSSIBLE AFTER ABOUT 13Z THURSDAY AHEAD OF
THE COLD FRONT WITH THE BOUNDARY MOVING ACROSS THE TERMINALS DURING
THE MIDDAY/EARLY AFTERNOON.
&&
.MARINE...
FORECAST WATERS RESIDE BETWEEN A RIDGE OF HIGH PRESSURE TO OUR EAST
AND A FRONTAL BOUNDARY OVER THE CENTRAL GULF OF MEXICO. SOUTH TO
SOUTHEAST FLOW WILL CONTINUE AHEAD OF THIS FRONT THROUGH TONIGHT.
THE COLD FRONT WILL STRENGTHEN AND QUICKLY TRANSLATE THROUGH THE
EASTERN GULF OF MEXICO ON THURSDAY. WINDS WILL SHIFT WEST AND
NORTHWEST BEHIND THE FRONT AND QUICKLY INCREASE TO HIGH END ADVISORY
LEVELS. THERE IS THE POTENTIAL FOR FREQUENT GUSTS TO NEAR GALE FORCE
THURSDAY AFTERNOON INTO THURSDAY NIGHT...ESPECIALLY NORTH OF
ENGLEWOOD...ALONG WITH SEAS BUILDING TO OVER 7 FEET AWAY FROM THE
COAST. WINDS WILL VEER TO THE NORTHEAST ON FRIDAY...BUT REMAIN
ELEVATED ALONG WITH SEAS THROUGH THE DAY.
&&
.FIRE WEATHER...
THE LONG PERIOD OF ABOVE AVERAGE TEMPERATURES IS COMING TO AN END
ACROSS THE FLORIDA PENINSULA. A COLD FRONT WILL CROSS THE AREA
THURSDAY AFTERNOON WITH A FEW SHOWERS AND THEN USHER IN A COOLER AND
DRIER AIRMASS FOR THE END OF THE WEEK. ALTHOUGH RELATIVE HUMIDITY
LEVELS WILL BE ABOVE CRITICAL VALUES ON THURSDAY...WINDS WILL BE
ELEVATED ALONG WITH DISPERSION INDICES. BREEZY CONDITIONS AND
ELEVATED DISPERSION INDICES ARE AGAIN EXPECTED FOR FRIDAY. AT THIS
TIME...THE FORECAST KEEPS RELATIVE HUMIDITY ABOVE 35 PERCENT...BUT
THE SITUATION WILL NEED TO BE MONITORED CLOSELY WITH FUTURE
FORECASTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 64 70 47 68 / 10 50 10 10
FMY 64 76 51 71 / 10 30 10 10
GIF 59 74 45 69 / 10 30 10 10
SRQ 64 71 50 69 / 10 40 10 10
BKV 57 70 42 66 / 10 50 10 10
SPG 66 69 50 66 / 10 50 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...GALE WATCH FROM THURSDAY AFTERNOON THROUGH LATE
THURSDAY NIGHT FOR ENGLEWOOD TO TARPON SPRINGS OUT 20 NM-
ENGLEWOOD TO TARPON SPRINGS OUT 20 TO 60 NM-TARPON
SPRINGS TO SUWANNEE RIVER OUT 20 NM-TARPON SPRINGS TO
SUWANNEE RIVER OUT 20 TO 60 NM.
&&
$$
SHORT TERM/MARINE/FIRE WX...MROCZKA
AVIATION...CLOSE
LONG TERM...OGLESBY
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
358 PM CST WED JAN 16 2013
.DISCUSSION...
TONIGHT AND THURSDAY...LOW PRES TRIPLE POINT CENTER TRAVERSING ESE
THRU WRN WI WITH THE CDFNT SNAKING EWD THRU KMSP TWD KABR...AND
THIS CDFNT WILL CONTINUE TO PRES SE THRU THE REST OF THE EVE.
BATCH OF -SN THAT PUSHED THROUGH MAINLY WRN AND SRN PORTIONS OF
THE TWIN CITIES REGION HAS SHIFTED OFF TO THE SE SO AM NOT
EXPECTING MUCH MORE OF ANY ACCUMULATING OR VISIBILITY-HAMPERING
SNOWFALL. THE SNOW WILL COME TO AN END OVER THE MPX CWFA BY LATE
EVENING THEN COLDER HIGH PRES WILL SLIDE SE LATE TNGT THRU TMRW.
SKIES WILL PARTIALLY CLEAR OUT...BUT THE MAIN IMPACT WILL BE
STRONGER CAA. AFTER HIGHS THAT RANGED THRU THE 30S THIS AFTN...THE
POST-FRONTAL CAA WILL FORCE LOWS THAT WILL SPAN FROM 10 DEGREES
ABOVE ZERO TO 10 DEGREES BELOW ZERO TONIGHT. THIS WILL THEN BE
FOLLOWED BY HIGHS FROM AROUND 10 TO THE LOWER 20S FOR THU.
THURSDAY NIGHT THROUGH SATURDAY...THE AREA OF HIGH PRES WILL ONLY
BE SHORT-LIVED AS IT SHIFTS OFF TO THE SE THU NIGHT INTO FRI WHILE
A WMFNT NUDGES IN FROM THE W. THIS WILL RESULT IN NOT ONLY A
WARMING TREND FRI INTO FRI NIGHT BUT ALSO THE POTENTIAL FOR SOME
SNOW SHOWERS OR LIGHT SNOW FOR MAINLY NRN AND ERN PORTIONS OF THE
MPX CWFA THU NIGHT THRU SAT AS THE FNT WILL SLOWLY LIFT OUT AND
GIVE WAY TO SEVERAL UPPER LEVEL DISTURBANCES PLUS A TRAILING CDFNT
FOR SAT. POPS ARE NO HIGHER THAN CHC RANGE AND ACCUMULATIONS...IF
ANY...WILL BE MINOR. AS FOR TEMPS...THE SIGNIFICANT WARM-UP FOR
FRI WILL BRING HIGHS AROUND 40 NEAR THE IA BORDER WITH 30S
ELSEWHERE THROUGHOUT THE CWFA. HOWEVER...THE MAIN CDFNT WHICH WILL
BE THE FOCUS FOR A SIGNIFICANT ARCTIC CHILL WILL PUSH THROUGH LATE
SAT SO ALTHOUGH HIGHS WILL DROP OFF ONLY TO THE LOW 20S TO LOW
30S... CAA WILL ABSOLUTELY COMMENCE BY LATE DAY SAT. WINDS WILL
ALSO BE ON THE INCRS DURG THE DAY SAT WITH A TIGHT POST-FRONTAL
PRES GRADIENT AND STRONG JETTING. WIND CHILL VALUES BY LATE DAY
SATURDAY WILL BE IN THE SINGLE DIGITS IN FAR SRN AND ERN
PORTIONS... WHILE NRN AND WRN PORTIONS WILL DROP TO AS LOW AS 20
DEGREES BELOW ZERO.
SATURDAY NIGHT THROUGH TUESDAY...THE ARCTIC BLAST WILL COMMENCE
OVER THE REGION STARTING SAT NIGHT AS A 1040-1050MB HIGH PRES
CENTER FROM NRN CANADA WILL DROP INTO THE NORTH-CENTRAL CONUS. IT
WILL SETTLE OVER THE AREA MON INTO MON NIGHT...MAKING THESE TWO
PERIODS THE COLDEST THIS REGION HAS SEEN IN SOME TIME. BREEZY
CONDITIONS WILL ALSO STILL BE PRESENT WITH THE COLD AIR...SO
COMBINING HIGHS RANGING FROM ZERO TO 10 BELOW ZERO ON MON FOLLOWED
BY LOWS MON NIGHT BETWEEN 10 AND 20 BELOW ZERO WILL MAKE FOR WIND
CHILL VALUES BETWEEN 20 AND 35 DEGREES BELOW ZERO. IT/S LOOKING
MORE AND MORE LIKELY THAT WIND CHILL ADVISORIES/WARNINGS WILL BE
NEEDED. AFTER TEMPS BOTTOM OUT MON NIGHT...THE HIGH PRES CENTER
WILL PUSH OFF TO THE E...ALLOWING A MORE SOUTHERLY FLOW. THIS
WILL ALLOW HIGHS ON TUE TO CLIMB INTO THE SINGLE DIGITS ABOVE
ZERO.
&&
.AVIATION.../00Z TAF ISSUANCE/
WITH SNOW RAPIDLY MOVING EAST ACROSS MN...WENT CONSIDERABLY MORE
PESSIMISTIC WITH THE 18Z TAFS. THESE TAFS BASED HEAVILY ON THE
RAP/HRRR...WHICH HAVE BOTH HANDLED THIS SNOW QUITE WELL THIS
MORNING. SEEING WIDESPREAD 1-3SM VIS SNOW ACROSS WRN MN RIGHT
NOW...WITH AN OCCASIONAL VIS UNDER 1SM. WITH SNOW BEING REPORTED
FROM MADISON TO LONG PRAIRIE...ALL TERMINALS LOOK TO GET IN THE
SNOW...WITH MSP/AXN BEING IN THE HEART OF THE BAND AND STC/RNH/EAU
BEING ON THE NORTH SIDE OF IT AND RWF BEING ON THE SOUTH SIDE. FOR
AXN/MSP...WENT WITH OUTRIGHT IFR VIS IN SNOW...WITH OUTER
LOCATIONS GETTING A TEMPO IFR TREATMENT. WILL BE A FAIRLY
PROGRESSIVE BAND OF SNOW...WITH MOST TERMINALS DONE WITH IT BY
00Z. IN ITS WAKE...EXPECT A BRIEF PERIOD OF SKC-FEW SKY
CONDS...BUT THE MPX AREA WILL BE REMAINING WITHIN A FRONTAL ZONE
ALOFT...WITH CLOUDS RETURNING BY THE END OF THE NIGHT. BASED ON
THE NAM/RAP...EXPECT ANOTHER ROUND OF MVFR CIGS TO MOVE OUT OF THE
DAKOTAS TONIGHT. CONFIDENCE NOT AS HIGH WITH THIS OCCURRING...BUT
WENT WITH THE STRATUS IDEA BASED ON CONTINUED COOLING NOTED ON
NAM BUFKIT SOUNDINGS OUT WEST. FOR WINDS...COLD FRONT IS JUST NOW
SLIPPING THROUGH RWF/MSP/EAU. WILL SEE WINDS BACK ALL THE WAY OVER
TO THE N IN WRN MN AND NW IN ERN MN/WRN WI. NOT EXPECTING AND HAVE
NOT SEEN MUCH IN THE WAY OF GUSTS...BUT SHOULD KEEP PERSISTENT
SUSTAINED SPEEDS IN THE 10-15 KT RANGE THROUGH THE REST OF THE DAY.
KMSP...SNOW IS RAPIDLY APPROACHING FROM THE WEST AND SHOULD BE AT
THE FIELD WITHIN THE FIRST HOUR. SOLID IFR OBS HAVE BEEN SEEN WITH
THIS BATCH OF SNOW ALL MORNING AND BASED ON THAT...SENT THE VIS
THAT DIRECTION FOR MSP. HRRR HAS CONTINUED TO HANDEL THIS ACTIVITY
WELL...AND FOLLOWED IT AND THE RAP CLOSELY FOR TIMING SNOW IN/OUT.
LOOKING AT NAM SOUNDINGS...MAY SEE A BRIEF MVFR CIG OR TWO
THURSDAY MORNING...BUT OTHERWISE...VFR CONDITIONS WILL DOMINATE
THIS TAF PERIOD ONCE THE AFTERNOON SNOW MOVES OUT.
/OUTLOOK FOR KMSP/
FRI...VFR. CHC OF -SN AND MVFR VIS/CIG IN MORNING. WIND SW 5-15
KTS.
SAT...MVFR CIGS LIKELY. AFTERNOON -SN POSSIBLE. W WIND 5 KTS BECOMING NW
15-20 KTS WITH GUSTS TO 30 KTS.
SUN...CHANCE OF -SN WITH MVFR OR LOWER CIG/VIS. WINDS W 5-10 KTS
BECOMING NW 15-20 KTS LATE.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
JPC/MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1234 PM CST WED JAN 16 2013
.UPDATE...
18Z AVIATION DISCUSSION ADDED BELOW.
JUST GOT THROUGH WITH SOME SWEEPING UPDATES TO THE GRIDS...WITH
THE BIG ONE TO DRASTICALLY INCREASE POPS FOR THIS
AFTERNOON...WITH LIKELY POPS NOW INDICATED FROM WEST CENTRAL MN
INTO THE TWIN CITIES. RAP H85/H7 FGEN LOCKING ON TO BAND OF
MODERATE SNOW MOVING OUT OF SE NODAK NOW...WITH THE HRRR
REFLECTIVITY FORECASTS THIS MORNING PICKING UP ON THE AREA AS
WELL. THE RAP TAKES THIS AREA OF FGEN FROM THE AXN AREA DOWN
TOWARD LA CROSSE BY THIS EVENING...WITH HRRR REFLECTIVITY FORECAST
FOLLOWING THIS AREA OF FORCING PRETTY MUCH LOCK AND STEP. AS A
RESULT...BOOSTED THE POPS QUITE A BIT...TAKING THE LEAD OF THE
HRRR/RAP FOR THE REST OF TODAY. NOT EXPECTING MUCH SNOWFALL WITH
THIS...WITH A HALF INCH OF SNOW ACCUMS CURRENTLY INDICATED IN THE
GRIDS. TIMING WISE...THIS LOOKS TO MOVE INTO THE TWIN CITIES JUST
IN TIME FOR THE EVENING COMMUTE...SO WE MAY END UP GOING 2 FOR 2
ON WEATHER SLOWED COMMUTES TODAY.
OTHER THAN POP/WX...INCREASED DEWPS SEVERAL DEGREES OUT AHEAD OF
THE FRONT...WHERE THEY HAVE INCREASED INTO THE 30S THIS
MORNING...AND SPED UP THE TEMP DROP IN THE NW CWA SOME THIS
AFTERNOON...AS WE ARE STARTING TO SEE SOME PRETTY GOOD CAA ACROSS
THE RED RIVER VALLEY...WHERE THE GRAND FORKS AREA IS ALREADY BACK
DOWN INTO THE SINGLE DIGITS.
&&
.PREV DISCUSSION...
/ISSUED 413 AM CST WED JAN 16 2013/
OVERVIEW...NO MAJOR CHANGES TO THE PREVIOUS FORECAST. BACKED OFF
ON THE POPS TODAY IN EASTERN MN AND WESTERN WI...TRAILING WAVE
BEHIND THE COLD FRONT JUST DOESNT LOOK OVERLY IMPRESSIVE.
INCREASED POPS A BIT WITH FRIDAY`S CLIPPER SYSTEM...AS THERE IS
PRETTY GOOD CONTINUITY WITH THAT SYSTEM OVER THE LAST COUPLE MODEL
RUNS. FINALLY...ONLY SLIGHT ADJUSTMENTS TO TEMPERATURES AND WIND
SPEEDS SUNDAY THROUGH MONDAY WITH THE BLAST OF ARCTIC AIR...BUT
ENDED UP WITH MORE LOCATIONS WITH APPARENT TEMPERATURES BETWEEN 30
AND 40 BELOW ZERO...EVEN AS EARLY AS SUNDAY NIGHT WHEN THE WIND
LOOKS TO BE BLUSTERY.
COLD FRONT AND SURFACE TROUGH MAKING STEADY PROGRESS ACROSS
MINNESOTA THIS MORNING. INTERESTING TEMPERATURE TREND THIS MORNING IN
WESTERN MN AND THE DAKOTAS. FOR EXAMPLE...THE TEMPERATURE AT
KGFK HAS GONE FROM 21...23...29...34...37...27...24...19 OVER THE
LAST 8 HOURS ENDING AT 4 AM. FARGO IS ACTUALLY REPORTING LIGHT
RAIN THIS MORNING AS WELL. COLDER AIR IS CERTAINLY ON THE WAY
BEHIND THIS CLIPPER SYSTEM AND IT SHOULD LIMIT TEMPS IN NORTHERN
PORTIONS OF THE FORECAST AREA TODAY. TRIED TO INCLUDE A NON-
DIURNAL TEMPERATURE TREND OVER THE NEXT 24 HOURS. GIVEN THE SPEED
OF THE COLD FRONT AND POSITION OF STRONGEST RADAR RETURNS IN
RELATION TO THIS FRONT...MOST OF MINNESOTA MIGHT ONLY END UP WITH
A FEW FLURRIES OR SPRINKLES TODAY. THE TRAILING WAVE IS SUBTLE AT
THIS POINT AND IT`S DIFFICULT EVEN TO PICK OUT IN WATER VAPOR.
THIS SHOULD VIRTUALLY BE A NON ISSUE IN TERMS OF PRECIP FOR
EASTERN MN AND WESTERN WI THIS AFTERNOON. REDUCED POPS...BUT DID
NOT GO COMPLETELY DRY...AND STILL KEEP 40%-50% GOING IN WESTERN
MN. TEMP FORECAST TODAY IS CHALLENGING...BUT EVEN WITH CLOUD COVER
WE MIGHT BE TOO COOL IN SPOTS WHERE WE HAVE MID 30S GOING GIVEN
THE QUICK WARM FRONTAL PASSAGE TODAY. MIGHT SEE A LOT OF UPPER 30S
AND POSSIBLY EVEN A COUPLE 40S.
THE 16.00Z GFS HAS JOGGED NORTH A BIT WITH FRIDAY`S CLIPPER
SYSTEM...THE ECMWF HAS COME FARTHER SOUTH BUT IS WEAKER AND
BROADER WITH THE SURFACE REFLECTION. STILL WORTH A MENTION OF SNOW
ON FRIDAY GIVEN THIS SIGNAL HAS BEEN SHOWING UP FOR A COUPLE DAYS
NOW. LIGHT SNOW LOOKS MORE PROMISING IN NORTHERN MN AND FAR
NORTHERN WI. THIS SYSTEM ACTUALLY HAS A TRAILING SURFACE LOW THAT
LINGERS INTO SATURDAY. THIS MIGHT MEAN MORE CLOUD COVER/PERHAPS
FLURRIES THAN WHAT IS CURRENTLY IN THE FORECAST.
WE`VE BEEN ADVERTISING THE STRONG ARCTIC AIR MASS FOR SUNDAY NIGHT
THROUGH MONDAY NIGHT...FOR AT LEAST TWO DAYS NOW. NOT MUCH CHANGE
WITH LAST NIGHTS MODEL RUNS...AS THE ARCTIC BOUNDARY COMES IN
QUICK AND THE AIR MASS ALREADY BEGINS TO MODERATE BY TUESDAY.
HOWEVER...THE LATEST FORECAST WIND CHILLS ARE IMPRESSIVELY COLD
EVEN SUNDAY NIGHT WITH HIGH BUILDING IN ACROSS THE DAKOTAS AND
REMNANT SURFACE TROUGH HANGING BACK OVER THE WARMER GREAT LAKES IN
THE WAKE OF THE CLIPPER SYSTEM. THERE SHOULD BE A STRONG PUSH OF
COLD AIR WITH THE ARCTIC BOUNDARY AND THE PRESSURE GRADIENT
SUGGESTS BLUSTERY WINDS AS COLD AIR ADVECTION KICKS IN GEAR.
MONDAY HAS A LOOK OF ONE THOSE CLASSICALLY COLD MN/WI DAYS YOU MAY
REMEMBER FROM YOUR CHILDHOOD...AND AT THE VERY LEAST SINCE 2009.
BREEZY NORTHERLY WINDS AND HIGH TEMPERATURES BETWEEN -2 AND -12
WITH SUNNY SKIES. THE LACK OF SNOW COVER IN PORTIONS OF WEST
CENTRAL WI AND SOUTHERN MN WILL KEEP TEMPS WARMER BY A FEW
DEGREES...BUT NONETHELESS...THIS WILL BE SOME OF THE COLDEST AIR
WE`VE SEEN IN THE LAST 3-4 YEARS. WE SHOULD SEE WIND CHILLS
BETWEEN 25 AND 40 BELOW ACROSS MUCH OF THE AREA. WIND CHILL
ADVISORY/WARNINGS WILL BE NEEDED SUNDAY/TUESDAY.
&&
.AVIATION.../00Z TAF ISSUANCE/
WITH SNOW RAPIDLY MOVING EAST ACROSS MN...WENT CONSIDERABLY MORE
PESSIMISTIC WITH THE 18Z TAFS. THESE TAFS BASED HEAVILY ON THE
RAP/HRRR...WHICH HAVE BOTH HANDLED THIS SNOW QUITE WELL THIS
MORNING. SEEING WIDESPREAD 1-3SM VIS SNOW ACROSS WRN MN RIGHT
NOW...WITH AN OCCASIONAL VIS UNDER 1SM. WITH SNOW BEING REPORTED
FROM MADISON TO LONG PRAIRIE...ALL TERMINALS LOOK TO GET IN THE
SNOW...WITH MSP/AXN BEING IN THE HEART OF THE BAND AND STC/RNH/EAU
BEING ON THE NORTH SIDE OF IT AND RWF BEING ON THE SOUTH SIDE. FOR
AXN/MSP...WENT WITH OUTRIGHT IFR VIS IN SNOW...WITH OUTER
LOCATIONS GETTING A TEMPO IFR TREATMENT. WILL BE A FAIRLY
PROGRESSIVE BAND OF SNOW...WITH MOST TERMINALS DONE WITH IT BY
00Z. IN ITS WAKE...EXPECT A BRIEF PERIOD OF SKC-FEW SKY
CONDS...BUT THE MPX AREA WILL BE REMAINING WITHIN A FRONTAL ZONE
ALOFT...WITH CLOUDS RETURNING BY THE END OF THE NIGHT. BASED ON
THE NAM/RAP...EXPECT ANOTHER ROUND OF MVFR CIGS TO MOVE OUT OF THE
DAKOTAS TONIGHT. CONFIDENCE NOT AS HIGH WITH THIS OCCURRING...BUT
WENT WITH THE STRATUS IDEA BASED ON CONTINUED COOLING NOTED ON
NAM BUFKIT SOUNDINGS OUT WEST. FOR WINDS...COLD FRONT IS JUST NOW
SLIPPING THROUGH RWF/MSP/EAU. WILL SEE WINDS BACK ALL THE WAY OVER
TO THE N IN WRN MN AND NW IN ERN MN/WRN WI. NOT EXPECTING AND HAVE
NOT SEEN MUCH IN THE WAY OF GUSTS...BUT SHOULD KEEP PERSISTENT
SUSTAINED SPEEDS IN THE 10-15 KT RANGE THROUGH THE REST OF THE DAY.
KMSP...SNOW IS RAPIDLY APPROACHING FROM THE WEST AND SHOULD BE AT
THE FIELD WITHIN THE FIRST HOUR. SOLID IFR OBS HAVE BEEN SEEN WITH
THIS BATCH OF SNOW ALL MORNING AND BASED ON THAT...SENT THE VIS
THAT DIRECTION FOR MSP. HRRR HAS CONTINUED TO HANDEL THIS ACTIVITY
WELL...AND FOLLOWED IT AND THE RAP CLOSELY FOR TIMING SNOW IN/OUT.
LOOKING AT NAM SOUNDINGS...MAY SEE A BRIEF MVFR CIG OR TWO
THURSDAY MORNING...BUT OTHERWISE...VFR CONDITIONS WILL DOMINATE
THIS TAF PERIOD ONCE THE AFTERNOON SNOW MOVES OUT.
/OUTLOOK FOR KMSP/
FRI...VFR. CHC OF -SN AND MVFR VIS/CIG IN MORNING. WIND SW 5-15
KTS.
SAT...MVFR CIGS LIKELY. AFTERNOON -SN POSSIBLE. W WIND 5 KTS BECOMING NW
15-20 KTS WITH GUSTS TO 30 KTS.
SUN...CHANCE OF -SN WITH MVFR OR LOWER CIG/VIS. WINDS W 5-10 KTS
BECOMING NW 15-20 KTS LATE.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
CLF/MPG
AREA FORECAST DISCUSSION
NWS DULUTH MN
1215 PM CST WED JAN 16 2013
.AVIATION.../18Z TAF ISSUANCE/
LOW CLOUDS ASSOC WITH A DEPARTING COLD FRONT WILL CONTINUE TO
DECREASE IN COVERAGE THIS AFTERNOON ACROSS MOST OF THE CWA. BY
THIS EVENING...MOST AREAS SHOULD SEE PARTLY CLOUDY SKIES AS HIGH
PRESSURE FROM CANADA BUILDS ACROSS THE UPPER MIDWEST. AREAS OF
STRATUS MAY REDEVELOP THURSDAY MORNING AS INDICATED BY THE NAM12
TIME/HEIGHT CROSS SECTION.
&&
.PREV DISCUSSION... /ISSUED 1016 AM CST WED JAN 16 2013/
UPDATE...
TOOK OUT MENTION OF FZDZ AND KEPT WITH SCATTERED FLURRIES INTO THE
EARLY AFTERNOON OVER THE NRN COUNTIES WITH LIGHT SNOW/FLURRIES
PERSISTING TO THE SOUTH AS A WEAK SYSTEM SLIDES THROUGH SRN MN.
MINOR CHANGES TO SKY COVER THIS MORNING AND AFTERNOON...HOLDING ON
TO CLOUDS INTO THE EARLY EVENING BEFORE CLEARING THINGS OUT
SOMEWHAT TONIGHT...AND GOING MAINLY PARTLY CLOUDY. STILL EXPECTING
A VERY COLD AIR MASS TO DROP IN ACROSS THE AREA TONIGHT AND BRING
TEMPS DOWN INTO THE TEENS AND 20S BELOW ZERO WITH WIND CHILL
READINGS -25 TO -35. WILL BE ISSUING A WIND CHILL ADVISORY FOR
TONIGHT WITH THE AFTERNOON FORECAST...AND POSSIBLY A WARNING FOR
THE FAR NRN COUNTIES.
PREV DISCUSSION... /ISSUED 551 AM CST WED JAN 16 2013/
AVIATION...12Z TAFS
IFR OR LOW MVFR CEILINGS COVERED MOST OF NORTHEAST
MINNESOTA EARLY THIS MORNING...WITH MVFR CEILINGS AND VSBYS FROM 1 TO 3
MILES IN SNOW OR FREEZING DRIZZLE WERE OCCURRING OVER NORTHWEST
WISCONSIN. MUCH OF THE PRECIPITATION WILL MOVE OUT OF THE
NORTHLAND THIS MORNING...AND CEILINGS WILL INCREASE TO MVFR. WE
FOLLOWED CLOSE TO THE RAP 925MB CONDENSATION PRESSURE DEFICITS TO
TIME CLEARING TODAY. GUSTY WEST TO NORTHWEST WINDS WILL OCCUR THIS
MORNING INTO EARLY AFTERNOON BEFORE DIMINISHING LATE.
PREV DISCUSSION... /ISSUED 408 AM CST WED JAN 16 2013/
SHORT TERM...TODAY THROUGH THURSDAY.
AT 4 AM...LIGHT SNOW CONTINUED TO SPREAD SOUTHEAST ACROSS THE CWA.
THE LOWEST VSBYS WERE NOW IN NW WI. THERE HAS ALSO BEEN SOME
PATCHY FREEZING DRIZZLE ACROSS THE AREA. TEMPERATURES WERE LARGELY
IN THE 20S.
THE MAIN FOCUS FOR THE MORNING WILL CONTINUE TO BE LIGHT SNOW AND
PATCHY FREEZING DRIZZLE. THE COMBINATION OF FREEZING DRIZZLE AND
SNOW WILL MAKE ROADS SLICK THIS MORNING. THE COLD FRONT WILL MOVE
QUICKLY SE ACROSS THE CWA THIS MORNING...FOLLOWED BY FALLING
TEMPERATURES DUE TO STRONG CAA BEHIND THE COLD FRONT. SW WINDS
WILL SWITCH TO THE NW AND BECOME GUSTY DURING THE AFTERNOON.
ARCTIC HIGH PRESSURE WILL BUILD ACROSS THE REGION TONIGHT...WITH
VERY COLD AIR SETTLING INTO THE NORTHLAND. HAVE DROPPED TEMPS EVEN
FURTHER FOR TONIGHT GIVEN THE STRENGTH OF THE ARCTIC AIR. EXPECT
TEMPERATURES TO FALL INTO THE MID 20S BELOW ZERO IN THE NORTH
TONIGHT. WITH WINDS SWITCHING TO THE NW...WE COULD ALSO SEE SOME
LAKE EFFECT SNOW SHOWERS ALONG THE SOUTH SHORE. NOT LOOKING FOR
TOO MUCH IN THE WAY OF SNOW ACCUMULATION AS WINDS WILL BE A BIT
WESTERLY.
ARCTIC HIGH PRESSURE WILL REINFORCE ITSELF ACROSS THE REGION ON
THURSDAY...WITH TEMPERATURES REMAINING BELOW ZERO ACROSS THE
NORTHERN THIRD OF THE CWA. ONCE THE CLOUDS SCOUR OUT THIS
AFTERNOON...WE SHOULD SEE A FAIR AMOUNT OF CLEAR SKIES TONIGHT
INTO THURSDAY.
LONG TERM...THURSDAY NIGHT THROUGH TUESDAY.
MAIN STORY IN THE EXTENDED WILL BE VERY COLD AIR MOVING OVER THE
REGION LATER IN THE WEEKEND...INTO THE MIDDLE OF NEXT WEEK.
UPPER RIDGE OVER THE WEST COAST/EASTERN PACIFIC WILL GRADUALLY SHIFT
OVER THE WESTERN CONUS LATE IN THE PERIOD. AN UPPER LOW OVER HUDSON
BAY WILL SHIFT EAST AND NORTH INTO THE WEEKEND...WITH SHORTWAVES
MOVING THROUGH AND MUCH COLDER AIR MOVING IN OVER THE WEEKEND.
A SHORTWAVE AND WAA WILL AFFECT THE CWA THURSDAY NIGHT LEADING TO A
CHANCE FOR LIGHT SNOW INTO FRIDAY. TEMPS SHOULD DROP QUICKLY
THURSDAY EVENING...THEN RISE OVERNIGHT WITH INCREASING CLOUDS/WAA.
GOOD WAA WILL LEAD TO ACCUMULATIONS FROM A DUSTING TO PERHAPS 2
INCHES. 850MB TEMPS ARE FORECAST TO RISE TO NEAR 0C ACROSS OUR
SOUTHWEST CWA ON FRIDAY...LEADING TO HIGHS IN THE UPPER TWENTIES TO
NEAR 30 IN OUR SOUTHERN ZONES.
ANOTHER WAVE AND SURFACE LOW WILL LEAD TO A CONTINUED CHANCE FOR
LIGHT SNOW FRIDAY NIGHT AND SATURDAY. THE WAVE ON SATURDAY IS
STRONGER...AND THE LATEST ECMWF SUGGESTS A FEW INCHES OF SNOW WILL
BE POSSIBLE...MAINLY OVER NORTHERN MINNESOTA. MUCH COLDER AIR WILL
POUR INTO THE NORTHLAND AS THE LOW PASSES ON SATURDAY. 850MB TEMPS
ARE FORECAST TO DROP TO -20 TO -22C OVER MUCH OF OUR MINNESOTA CWA
SATURDAY AFTERNOON...WITH EVEN COLDER TEMPS MOVING IN SUNDAY NIGHT.
A FAVORABLE PERIOD FOR SIGNIFICANT LES WILL OCCUR ALONG THE SOUTH
SHORE AS THE COLDER AIR MOVES IN SATURDAY AFTERNOON/NIGHT.
COLD WILL BE THE MAIN STORY SUNDAY INTO TUESDAY. LOWS SUNDAY NIGHT
INTO TUESDAY NIGHT WILL BE IN THE TEENS BELOW ZERO TO MID TWENTIES
BELOW. THERE WILL BE ENOUGH WIND SATURDAY NIGHT TO CREATE SOME VERY
LOW WIND CHILLS. HIGHS SUNDAY INTO TUESDAY ARE FORECAST TO REMAIN AT
OR BELOW ZERO OVER NORTHEAST MINNESOTA...AND ONLY BE A FEW DEGREES
WARMER OVER NORTHWEST WISCONSIN.
&&
.POINT TEMPS/POPS...
DLH -13 4 -2 26 / 10 10 40 50
INL -24 -4 -15 18 / 10 10 40 50
BRD -8 9 4 29 / 10 10 40 20
HYR -11 10 -2 30 / 10 10 40 40
ASX -4 10 4 28 / 40 20 40 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
AVIATION...BERDES
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1030 AM CST WED JAN 16 2013
.UPDATE...
JUST GOT THROUGH WITH SOME SWEEPING UPDATES TO THE GRIDS...WITH
THE BIG ONE TO DRASTICALLY INCREASE POPS FOR THIS
AFTERNOON...WITH LIKELY POPS NOW INDICATED FROM WEST CENTRAL MN
INTO THE TWIN CITIES. RAP H85/H7 FGEN LOCKING ON TO BAND OF
MODERATE SNOW MOVING OUT OF SE NODAK NOW...WITH THE HRRR
REFLECTIVITY FORECASTS THIS MORNING PICKING UP ON THE AREA AS
WELL. THE RAP TAKES THIS AREA OF FGEN FROM THE AXN AREA DOWN
TOWARD LA CROSSE BY THIS EVENING...WITH HRRR REFLECTIVITY FORECAST
FOLLOWING THIS AREA OF FORCING PRETTY MUCH LOCK AND STEP. AS A
RESULT...BOOSTED THE POPS QUITE A BIT...TAKING THE LEAD OF THE
HRRR/RAP FOR THE REST OF TODAY. NOT EXPECTING MUCH SNOWFALL WITH
THIS...WITH A HALF INCH OF SNOW ACCUMS CURRENTLY INDICATED IN THE
GRIDS. TIMING WISE...THIS LOOKS TO MOVE INTO THE TWIN CITIES JUST
IN TIME FOR THE EVENING COMMUTE...SO WE MAY END UP GOING 2 FOR 2
ON WEATHER SLOWED COMMUTES TODAY.
OTHER THAN POP/WX...INCREASED DEWPS SEVERAL DEGREES OUT AHEAD OF
THE FRONT...WHERE THEY HAVE INCREASED INTO THE 30S THIS
MORNING...AND SPED UP THE TEMP DROP IN THE NW CWA SOME THIS
AFTERNOON...AS WE ARE STARTING TO SEE SOME PRETTY GOOD CAA ACROSS
THE RED RIVER VALLEY...WHERE THE GRAND FORKS AREA IS ALREADY BACK
DOWN INTO THE SINGLE DIGITS.
&&
.PREV DISCUSSION...
/ISSUED 413 AM CST WED JAN 16 2013/
OVERVIEW...NO MAJOR CHANGES TO THE PREVIOUS FORECAST. BACKED OFF
ON THE POPS TODAY IN EASTERN MN AND WESTERN WI...TRAILING WAVE
BEHIND THE COLD FRONT JUST DOESNT LOOK OVERLY IMPRESSIVE.
INCREASED POPS A BIT WITH FRIDAY`S CLIPPER SYSTEM...AS THERE IS
PRETTY GOOD CONTINUITY WITH THAT SYSTEM OVER THE LAST COUPLE MODEL
RUNS. FINALLY...ONLY SLIGHT ADJUSTMENTS TO TEMPERATURES AND WIND
SPEEDS SUNDAY THROUGH MONDAY WITH THE BLAST OF ARCTIC AIR...BUT
ENDED UP WITH MORE LOCATIONS WITH APPARENT TEMPERATURES BETWEEN 30
AND 40 BELOW ZERO...EVEN AS EARLY AS SUNDAY NIGHT WHEN THE WIND
LOOKS TO BE BLUSTERY.
COLD FRONT AND SURFACE TROUGH MAKING STEADY PROGRESS ACROSS
MINNESOTA THIS MORNING. INTERESTING TEMPERATURE TREND THIS MORNING IN
WESTERN MN AND THE DAKOTAS. FOR EXAMPLE...THE TEMPERATURE AT
KGFK HAS GONE FROM 21...23...29...34...37...27...24...19 OVER THE
LAST 8 HOURS ENDING AT 4 AM. FARGO IS ACTUALLY REPORTING LIGHT
RAIN THIS MORNING AS WELL. COLDER AIR IS CERTAINLY ON THE WAY
BEHIND THIS CLIPPER SYSTEM AND IT SHOULD LIMIT TEMPS IN NORTHERN
PORTIONS OF THE FORECAST AREA TODAY. TRIED TO INCLUDE A NON-
DIURNAL TEMPERATURE TREND OVER THE NEXT 24 HOURS. GIVEN THE SPEED
OF THE COLD FRONT AND POSITION OF STRONGEST RADAR RETURNS IN
RELATION TO THIS FRONT...MOST OF MINNESOTA MIGHT ONLY END UP WITH
A FEW FLURRIES OR SPRINKLES TODAY. THE TRAILING WAVE IS SUBTLE AT
THIS POINT AND IT`S DIFFICULT EVEN TO PICK OUT IN WATER VAPOR.
THIS SHOULD VIRTUALLY BE A NON ISSUE IN TERMS OF PRECIP FOR
EASTERN MN AND WESTERN WI THIS AFTERNOON. REDUCED POPS...BUT DID
NOT GO COMPLETELY DRY...AND STILL KEEP 40%-50% GOING IN WESTERN
MN. TEMP FORECAST TODAY IS CHALLENGING...BUT EVEN WITH CLOUD COVER
WE MIGHT BE TOO COOL IN SPOTS WHERE WE HAVE MID 30S GOING GIVEN
THE QUICK WARM FRONTAL PASSAGE TODAY. MIGHT SEE A LOT OF UPPER 30S
AND POSSIBLY EVEN A COUPLE 40S.
THE 16.00Z GFS HAS JOGGED NORTH A BIT WITH FRIDAY`S CLIPPER
SYSTEM...THE ECMWF HAS COME FARTHER SOUTH BUT IS WEAKER AND
BROADER WITH THE SURFACE REFLECTION. STILL WORTH A MENTION OF SNOW
ON FRIDAY GIVEN THIS SIGNAL HAS BEEN SHOWING UP FOR A COUPLE DAYS
NOW. LIGHT SNOW LOOKS MORE PROMISING IN NORTHERN MN AND FAR
NORTHERN WI. THIS SYSTEM ACTUALLY HAS A TRAILING SURFACE LOW THAT
LINGERS INTO SATURDAY. THIS MIGHT MEAN MORE CLOUD COVER/PERHAPS
FLURRIES THAN WHAT IS CURRENTLY IN THE FORECAST.
WE`VE BEEN ADVERTISING THE STRONG ARCTIC AIR MASS FOR SUNDAY NIGHT
THROUGH MONDAY NIGHT...FOR AT LEAST TWO DAYS NOW. NOT MUCH CHANGE
WITH LAST NIGHTS MODEL RUNS...AS THE ARCTIC BOUNDARY COMES IN
QUICK AND THE AIR MASS ALREADY BEGINS TO MODERATE BY TUESDAY.
HOWEVER...THE LATEST FORECAST WIND CHILLS ARE IMPRESSIVELY COLD
EVEN SUNDAY NIGHT WITH HIGH BUILDING IN ACROSS THE DAKOTAS AND
REMNANT SURFACE TROUGH HANGING BACK OVER THE WARMER GREAT LAKES IN
THE WAKE OF THE CLIPPER SYSTEM. THERE SHOULD BE A STRONG PUSH OF
COLD AIR WITH THE ARCTIC BOUNDARY AND THE PRESSURE GRADIENT
SUGGESTS BLUSTERY WINDS AS COLD AIR ADVECTION KICKS IN GEAR.
MONDAY HAS A LOOK OF ONE THOSE CLASSICALLY COLD MN/WI DAYS YOU MAY
REMEMBER FROM YOUR CHILDHOOD...AND AT THE VERY LEAST SINCE 2009.
BREEZY NORTHERLY WINDS AND HIGH TEMPERATURES BETWEEN -2 AND -12
WITH SUNNY SKIES. THE LACK OF SNOW COVER IN PORTIONS OF WEST
CENTRAL WI AND SOUTHERN MN WILL KEEP TEMPS WARMER BY A FEW
DEGREES...BUT NONETHELESS...THIS WILL BE SOME OF THE COLDEST AIR
WE`VE SEEN IN THE LAST 3-4 YEARS. WE SHOULD SEE WIND CHILLS
BETWEEN 25 AND 40 BELOW ACROSS MUCH OF THE AREA. WIND CHILL
ADVISORY/WARNINGS WILL BE NEEDED SUNDAY/TUESDAY.
&&
.AVIATION.../12Z TAF ISSUANCE/
FIRST AREA OF LIGHT SNOW FOR TODAY ASSOCIATED WITH WARM AIR
ADVECTION AND THIS IS MOVING QUICKLY SOUTHEAST WITH SOME
REDEVELOPMENT. SYSTEM IS STRENGTHENING A BIT AND VSBYS HAVE
DROPPED IN ERN MN AND WESTERN WISC. WILL HAVE SOME IFR VSBY THIS
MORNING WHILE CEILINGS STAY GENERALLY IN THE 1000-1500 FOOT AGL
LAYER. HOWEVER...A FEW AREAS WILL HAVE IFR CIGS.
SOME LOWER CEILINGS BEHIND PRECIP...AND ALSO COLD ADVECTION BEHIND
COLD FRONT ENTERING CENTRAL MN HAS LED TO SOME IFR CEILINGS WHICH
WILL AFFECT AXN/STC FOR A FEW HOURS THIS MORNING.
SECOND BATCH OF LIGHT SNOW LOOKS TO MOVE INTO WEST CENTRAL INTO
SOUTH CENTRAL MN LATE MORNING AND AFTERNOON. KRWF WILL SEE MVFR
CIGS/VSBY THIS AFTERNOON. THERE IS A SMALL CHANCE IT COULD LOWER
TO IFR BUT HAVE NOT ADDED THIS TO TAF. AFTER THAT...VFR CONDITIONS
WITH NW WIND GRADUALLY DIMINISHING TO 5-7 KTS TONIGHT.
KMSP...IFR VSBY IN LIGHT SNOW WILL PERSIST TIL 14Z. AFTER THAT...
EXPECT MVFR CIGS/VSBYS THE REST OF THE MORNING. LIGHT SNOW THIS AFTERNOON
SHOULD AFFECT WEST CENTRAL INTO SOUTH CENTRAL MN AND THEREFORE BYPASS
KMSP TO THE SOUTHWEST. THERE IS A SMALL CHANCE OF FLURRIES THIS
AFTERNOON BUT NOT ENOUGH CONFIDENCE TO ADD THAT. NW WIND WILL
DECREASE THIS EVENING.
/OUTLOOK FOR KMSP/
THU...VFR. W WIND 5-10 KTS.
FRI...VFR. CHC FLURRIES. SW WIND 5-15 KTS.
SAT...MVFR CIGS LIKELY. CHC MVFR VSBY. W WIND 5 KTS BECOMING NW
15-20 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
MPG/CLF/TDK
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1016 AM CST WED JAN 16 2013
.UPDATE...
TOOK OUT MENTION OF FZDZ AND KEPT WITH SCATTERED FLURRIES INTO THE
EARLY AFTERNOON OVER THE NRN COUNTIES WITH LIGHT SNOW/FLURRIES
PERSISTING TO THE SOUTH AS A WEAK SYSTEM SLIDES THROUGH SRN MN.
MINOR CHANGES TO SKY COVER THIS MORNING AND AFTERNOON...HOLDING ON
TO CLOUDS INTO THE EARLY EVENING BEFORE CLEARING THINGS OUT
SOMEWHAT TONIGHT...AND GOING MAINLY PARTLY CLOUDY. STILL EXPECTING
A VERY COLD AIR MASS TO DROP IN ACROSS THE AREA TONIGHT AND BRING
TEMPS DOWN INTO THE TEENS AND 20S BELOW ZERO WITH WIND CHILL
READINGS -25 TO -35. WILL BE ISSUING A WIND CHILL ADVISORY FOR
TONIGHT WITH THE AFTERNOON FORECAST...AND POSSIBLY A WARNING FOR
THE FAR NRN COUNTIES.
&&
.PREV DISCUSSION... /ISSUED 551 AM CST WED JAN 16 2013/
AVIATION...12Z TAFS
IFR OR LOW MVFR CEILINGS COVERED MOST OF NORTHEAST
MINNESOTA EARLY THIS MORNING...WITH MVFR CEILINGS AND VSBYS FROM 1 TO 3
MILES IN SNOW OR FREEZING DRIZZLE WERE OCCURRING OVER NORTHWEST
WISCONSIN. MUCH OF THE PRECIPITATION WILL MOVE OUT OF THE
NORTHLAND THIS MORNING...AND CEILINGS WILL INCREASE TO MVFR. WE
FOLLOWED CLOSE TO THE RAP 925MB CONDENSATION PRESSURE DEFICITS TO
TIME CLEARING TODAY. GUSTY WEST TO NORTHWEST WINDS WILL OCCUR THIS
MORNING INTO EARLY AFTERNOON BEFORE DIMINISHING LATE.
PREV DISCUSSION... /ISSUED 408 AM CST WED JAN 16 2013/
SHORT TERM...TODAY THROUGH THURSDAY.
AT 4 AM...LIGHT SNOW CONTINUED TO SPREAD SOUTHEAST ACROSS THE CWA.
THE LOWEST VSBYS WERE NOW IN NW WI. THERE HAS ALSO BEEN SOME
PATCHY FREEZING DRIZZLE ACROSS THE AREA. TEMPERATURES WERE LARGELY
IN THE 20S.
THE MAIN FOCUS FOR THE MORNING WILL CONTINUE TO BE LIGHT SNOW AND
PATCHY FREEZING DRIZZLE. THE COMBINATION OF FREEZING DRIZZLE AND
SNOW WILL MAKE ROADS SLICK THIS MORNING. THE COLD FRONT WILL MOVE
QUICKLY SE ACROSS THE CWA THIS MORNING...FOLLOWED BY FALLING
TEMPERATURES DUE TO STRONG CAA BEHIND THE COLD FRONT. SW WINDS
WILL SWITCH TO THE NW AND BECOME GUSTY DURING THE AFTERNOON.
ARCTIC HIGH PRESSURE WILL BUILD ACROSS THE REGION TONIGHT...WITH
VERY COLD AIR SETTLING INTO THE NORTHLAND. HAVE DROPPED TEMPS EVEN
FURTHER FOR TONIGHT GIVEN THE STRENGTH OF THE ARCTIC AIR. EXPECT
TEMPERATURES TO FALL INTO THE MID 20S BELOW ZERO IN THE NORTH
TONIGHT. WITH WINDS SWITCHING TO THE NW...WE COULD ALSO SEE SOME
LAKE EFFECT SNOW SHOWERS ALONG THE SOUTH SHORE. NOT LOOKING FOR
TOO MUCH IN THE WAY OF SNOW ACCUMULATION AS WINDS WILL BE A BIT
WESTERLY.
ARCTIC HIGH PRESSURE WILL REINFORCE ITSELF ACROSS THE REGION ON
THURSDAY...WITH TEMPERATURES REMAINING BELOW ZERO ACROSS THE
NORTHERN THIRD OF THE CWA. ONCE THE CLOUDS SCOUR OUT THIS
AFTERNOON...WE SHOULD SEE A FAIR AMOUNT OF CLEAR SKIES TONIGHT
INTO THURSDAY.
LONG TERM...THURSDAY NIGHT THROUGH TUESDAY.
MAIN STORY IN THE EXTENDED WILL BE VERY COLD AIR MOVING OVER THE
REGION LATER IN THE WEEKEND...INTO THE MIDDLE OF NEXT WEEK.
UPPER RIDGE OVER THE WEST COAST/EASTERN PACIFIC WILL GRADUALLY SHIFT
OVER THE WESTERN CONUS LATE IN THE PERIOD. AN UPPER LOW OVER HUDSON
BAY WILL SHIFT EAST AND NORTH INTO THE WEEKEND...WITH SHORTWAVES
MOVING THROUGH AND MUCH COLDER AIR MOVING IN OVER THE WEEKEND.
A SHORTWAVE AND WAA WILL AFFECT THE CWA THURSDAY NIGHT LEADING TO A
CHANCE FOR LIGHT SNOW INTO FRIDAY. TEMPS SHOULD DROP QUICKLY
THURSDAY EVENING...THEN RISE OVERNIGHT WITH INCREASING CLOUDS/WAA.
GOOD WAA WILL LEAD TO ACCUMULATIONS FROM A DUSTING TO PERHAPS 2
INCHES. 850MB TEMPS ARE FORECAST TO RISE TO NEAR 0C ACROSS OUR
SOUTHWEST CWA ON FRIDAY...LEADING TO HIGHS IN THE UPPER TWENTIES TO
NEAR 30 IN OUR SOUTHERN ZONES.
ANOTHER WAVE AND SURFACE LOW WILL LEAD TO A CONTINUED CHANCE FOR
LIGHT SNOW FRIDAY NIGHT AND SATURDAY. THE WAVE ON SATURDAY IS
STRONGER...AND THE LATEST ECMWF SUGGESTS A FEW INCHES OF SNOW WILL
BE POSSIBLE...MAINLY OVER NORTHERN MINNESOTA. MUCH COLDER AIR WILL
POUR INTO THE NORTHLAND AS THE LOW PASSES ON SATURDAY. 850MB TEMPS
ARE FORECAST TO DROP TO -20 TO -22C OVER MUCH OF OUR MINNESOTA CWA
SATURDAY AFTERNOON...WITH EVEN COLDER TEMPS MOVING IN SUNDAY NIGHT.
A FAVORABLE PERIOD FOR SIGNIFICANT LES WILL OCCUR ALONG THE SOUTH
SHORE AS THE COLDER AIR MOVES IN SATURDAY AFTERNOON/NIGHT.
COLD WILL BE THE MAIN STORY SUNDAY INTO TUESDAY. LOWS SUNDAY NIGHT
INTO TUESDAY NIGHT WILL BE IN THE TEENS BELOW ZERO TO MID TWENTIES
BELOW. THERE WILL BE ENOUGH WIND SATURDAY NIGHT TO CREATE SOME VERY
LOW WIND CHILLS. HIGHS SUNDAY INTO TUESDAY ARE FORECAST TO REMAIN AT
OR BELOW ZERO OVER NORTHEAST MINNESOTA...AND ONLY BE A FEW DEGREES
WARMER OVER NORTHWEST WISCONSIN.
&&
.POINT TEMPS/POPS...
DLH 27 -13 4 -2 / 10 10 10 40
INL 17 -24 -4 -15 / 10 10 10 40
BRD 30 -8 9 4 / 20 10 10 40
HYR 28 -11 10 -2 / 20 10 10 40
ASX 27 -4 10 4 / 20 40 20 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...TENTINGER
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
310 PM EST WED JAN 16 2013
.SYNOPSIS...
DEEP LAYER HIGH PRESSURE TONIGHT WILL GIVE WAY TO A PERIOD OF
WIND AND RAIN WITH THE BRUNT OF THE UNSETTLED WEATHER ARRIVING
LATER THURSDAY AFTERNOON AND INTO THURSDAY NIGHT. NEAR RECORD
WARMTH WILL BE REPLACED BY A WINTER CHILL BEGINNING LATE THURSDAY
NIGHT AND PERSISTING THROUGH THE WEEKEND AND EARLY NEXT WEEK AS
COLD AIR IS REINFORCED BY SUCCESSIVE COLD FRONT.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AS OF 3 PM WEDNESDAY...HAVE TWEAKED THE OVERCAST SKIES TO THE
EAST SLIGHTLY BASED ON MOST RECENT SATELLITE TRENDS. RUC CONTINUES
TO SHOW THE COAST REMAINING CLEAR FOR THE NEXT FEW HOURS AND IT
WOULD APPEAR CLOUD COVER WILL BE MORE UPDATE CENTRIC FOR THE NEAR
TERM.
WATER VAPOR IMAGERY SHOWING ESSENTIALLY THE SAME PATTERN AS WE
HAVE OBSERVED FOR DAYS NOW...A PLUME OF MOISTURE MOVING ACROSS THE
TENNESSEE/MISSISSIPPI VALLEY WITH DRY AIR MOVING IN ALONG THE
SOUTHEAST COAST. MID LEVEL PATTERN WILL BE CHANGING DRAMATICALLY
OVER THE NEXT FEW DAYS BUT NOT NECESSARILY THROUGH 1200 UTC
THURSDAY. IN FACT...ONLY WEAK FORCING...LOW LEVEL FRONTOGENESIS IS
ADVERTISED BY THE MAJOR MODELS THROUGH THROUGH THURSDAY MORNING
ACROSS OUR WESTERN AREAS AND HAVE TRENDED BACK MINIMAL POP VALUES.
GUIDANCE ALSO SHOWS OVERCAST SKIES/BOUNDARY WAVERING IN PLACE
THROUGH THE OVERNIGHT HOURS WITHOUT MOVING A LOT. FINALLY...WARMER
GFS MAV NUMBERS SEEM A SAFE BET BASED ON PERSISTENCE FOR OVERNIGHT
LOWS.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...TEMPERATURES MORE TYPICAL OF WINTER WILL
RETURN TO THE AREA DURING THIS PERIOD. IN FACT...FOR THE FIRST
TIME SINCE JAN 5-6...TEMPS WILL BE BELOW NORMAL.
A COLD FRONT WILL CONTINUE ITS DRIFT TOWARD THE AREA INTO THU. AN
AREA OF LOW PRESSURE WILL DEVELOP IN RESPONSE TO APPROACHING
SHORTWAVE ENERGY. UNTIL THIS LOW MOVES OVERHEAD AND THEN NE OF THE
AREA...THE EASTERN CAROLINAS WILL REMAIN LARGELY IN THE WARM SECTOR.
TEMPS WILL BE TRICKY ON THU GIVEN THE PROXIMITY OF THE COLD FRONT
AND THICKENING CLOUDS AND EVENTUALLY THE ONSET OF RAIN. AT THIS
TIME...EXPECT A RATHER TIGHT TEMP GRADIENT WITH THU AFTERNOON HIGHS
RANGING FROM AROUND 60 DEGREES ACROSS THE NW CORNER OF THE FORECAST
AREA TO LOWER AND MID 70S ACROSS MOST OF THE AREA ALONG AND S OF A
LINE FROM NEAR BURGAW TO WHITEVILLE TO DILLON TO DARLINGTON. THIS
TIGHT GRADIENT COLD EASILY BE A LITTLE FURTHER N OR S OF THIS
POSITION...SO THE HIGH TEMPS ON THU MAY CHANGE WITH LATER FORECASTS.
WHAT IS A VIRTUAL SLAM DUNK IS A PERIOD OF RAIN...ESPECIALLY LATER
THU AND THU EVE DUE TO CONTRIBUTIONS FROM INSTABILITY ALONG THE
FRONT...PVA...UPPER DIFFLUENCE IN THE VICINITY OF THE STRONG UPPER
JET AND LIFT ASSOCIATED WITH AN AREA OF STRENGTHENING LOW PRESSURE.
THE LAYER OF SATURATION INCREASES TO ABOUT 17 KFT AND PRECIPITABLE
WATER VALUES CLIMB TO ONE AND ONE-HALF INCHES. THUS A PERIOD OF
MODERATE TO HEAVY RAIN IS EXPECTED...ESPECIALLY DURING THE EVENING
HOURS OF THU. AS THE AREA OF LOW PRESSURE MOVES BY...COLD AIR WILL
GET DRAWN INTO THE EASTERN CAROLINAS AS THE COLD FRONT SURGES S. AT
THE SAME TIME THE COLD AIR IS ARRIVING...THE COLUMN WILL BE RAPIDLY
DRYING AND IT LOOKS AS THOUGH THE RAIN WILL END BEFORE IT HAS A
CHANCE TO CHANGEOVER OR MIX WITH A BRIEF PERIOD OF SNOW AS THE
CRITICAL DENDRITIC GROWTH ZONE IS THE FIRST TO DRY OUT.
WE ARE FORECASTING ALL RAIN ACROSS THE ILM FORECAST AREA AND THE
WINTER WEATHER TOP DOWN METHODOLOGY WAS APPLIED TO PRODUCE THIS
FORECAST. ANY SNOW WITH THIS SYSTEM WILL REMAIN N AND NW OF THE AREA
AND THERE WILL LIKELY BE SOME ACCUMULATION OF SNOW ACROSS THE
NORTHERN 2/3RDS OR SO OF NORTH CAROLINA. RAINFALL AMOUNTS OF 1/2 TO
1 INCH WILL BE MOST COMMON...HOWEVER SOME AREAS MAY RECEIVE SLIGHTLY
MORE QPF...WITH THE HIGHEST PROBABILITY FOR THIS ACROSS THE CAPE
FEAR RIVER BASIN. OTHER AREAS MAY RECEIVE SLIGHTLY LESS QPF...WITH
THE HIGHEST PROBABILITY ACROSS THE SOUTHERN GRAND STRAND AND
GEORGETOWN.
DEVELOPING CAA IN THE WAKE OF DEPARTING AND INTENSIFYING LOW
PRESSURE WILL ALLOW THE PRESSURE GRADIENT TO TIGHTEN AND WIND GUSTS
TO AROUND 30 MPH ARE EXPECTED THU NIGHT. 850 MB TEMPS WILL DROP TO
AROUND MINUS 2 DEG C BY FRI MORNING. LOWS BY FRI MORNING WILL BE
WELL DOWN IN THE 30S...AND NW PORTIONS OF THE FORECAST AREA WILL BE
CLOSE TO FREEZING FRI MORNING. TEMPS WILL STRUGGLE EVEN WITH BRIGHT
SUNSHINE ON FRI...AND THE FORECAST TEMP PROFILES SUGGEST TEMPS WILL
NEVER REACH 50 IN MOST LOCATIONS WITH MID 40S MOST COMMON.
AS HIGH PRESSURE POSITIONS ITSELF OVERHEAD...IT WILL BE COLD FRI
NIGHT...CLEAR SKIES AND LIGHT TO CALM WINDS WILL QUICKLY DRIVE TEMPS
INTO THE 20S AND AS LOW AS THE LOWER 20S IN THOSE AREAS WHERE
RADIATIONAL COOLING IS MAXIMIZED LONGEST.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 3 PM WEDNESDAY...WEAKENING SURFACE HIGH PRESSURE AND ZONAL MID
LEVEL FLOW IN PLACE OVER THE WEEKEND. TEMPERATURES WILL BE QUITE
CLOSE TO CLIMO AND AMPLE SUNSHINE EXPECTED. A SERIES OF
MOISTURE-DEPRIVED COLD FRONTS WILL MARCH SOUTHWARD ACROSS THE AREA
EARLY NEXT WEEK. THE FIRST COMES THROUGH LATE SUNDAY OR SUNDAY
NIGHT. THE SECOND STRONGER PUSH COMES MONDAY NIGHT. TEMPS WILL THUS
FALL A LITTLE BELOW CLIMO BY MONDAY WHEREAS THE BALANCE OF THE LONG
TERM WILL BRING SOME DOWNRIGHT COLD WEATHER WITH HIGHS STUCK IN THE
40S AND LOWS LOWER 20S. NATURALLY THERE IS SOME DISAGREEMENT BETWEEN
VARIOUS MODELS REGARDING THE MAGNITUDE OF THE COLD SO FAR OUT IN
TIME.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 18Z...TRICKY FORECAST ALONG THE COAST WITH SEA FOG LURKING.
THINK WIND TRAJECTORY WILL KEEP IT JUST OFFSHORE THROUGH THE
AFTERNOON HOURS...BUT AS THE WIND DIES AFTER SUNSET LOOK FOR THE
STRATUS TO MOVE BACK IN...FIRST AT THE MYRTLES AND LATER AT ILM.
EVENTUALLY LBT AND FLO WILL GO DOWN WITH ALL THE LOW LEVEL
MOISTURE IN PLACE. WINDS MAY STAY ABOVE 5 KTS TONIGHT...WHICH
COULD HELP TO KEEP VISIBILITIES UP A BIT MORE THAN LAST NIGHT.
THURSDAY...FRONTAL SYSTEM APPROACHES...BUT ANY RAIN WILL HOLD OFF
UNTIL AFTER THE END OF THE FORECAST PERIOD. WINDS WILL SHIFT MORE
SOUTH SOUTHEASTERLY...WITH A TROUGH INLAND.
EXTENDED OUTLOOK...RAIN/MVFR/IFR LIKELY THURSDAY INTO EARLY FRIDAY.
VFR DEVELOPING FRIDAY AND PERSISTING THROUGH MONDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM WEDNESDAY...A RELATIVELY BENIGN SOUTHWESTERLY FLOW OF
10-15 KNOTS WILL CONTINUE THROUGH THE PERIOD. INITIALLY BUOY
OBSERVATIONS SHOW VALUES CLOSER TO THE LOWER END OF THE RANGE WITH
41013 NOW AT NINE KNOTS. JMPN7 IS MUCH HIGHER THANKS TO SEA BREEZE
AFFECTS AT 22 KNOTS. SWELL ENERGY HAS ALL BUT DISSIPATED AND
WAVEWATCH SHOWS THIS TREND REMAINS INTACT FOR THE NEXT 12-18
HOURS. SIGNIFICANT SEAS OF 2-4 FEET CAN BE EXPECTED.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...A GALE WATCH HAS BEEN ISSUED FOR ALL WATERS
FOR LATER THU AFTERNOON AND THROUGH THE DAY ON FRI. THE STRONGEST
WINDS AND HIGHEST SEAS ARE EXPECTED THU NIGHT. WINDS ARE EXPECTED TO
AT LEAST REACH GALE FORCE IN GUSTS WITH THE BEST CHANCE FOR
SUSTAINED WINDS TO GALE FORCE ACROSS THE NORTHERN WATERS...ON THE
BACK SIDE OF AN INTENSIFYING AND DEPARTING AREA OF LOW PRESSURE.
WINDS WILL BE FROM A SOUTHERLY DIRECTION THU...SHIFTING TO W AND
THEN NW THU EVE AS A COLD FRONT SURGES ACROSS THE WATERS. NW WINDS
WILL VEER TO N OVERNIGHT THU WITH N WINDS ON FRI VEERING TO NE FRI
NIGHT AS THE CENTER OF HIGH PRESSURE APPROACHES. SEAS WILL REACH UP
TO 7 TO 9 FT THU NIGHT. SEAS WILL SUBSIDE THROUGH THE DAY ON FRI AND
THIS TREND WILL PERSIST FRI NIGHT.
LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 3 PM WEDNESDAY...EAST-WEST ELONGATED HIGH PRESSURE WITH AXIS
RIGHT ACROSS THE REGION TO KEEP WINDS QUITE LITE ON SATURDAY. SEAS
WILL QUICKLY SETTLE DOWN TO ABOUT 2 FT. AT THE START OF THE PERIOD
THERE MAY STILL BE A LINGERING SWELL YIELDING A NEARSHORE/OFFSHORE
GRADIENT IN SEA HEIGHT BUT THE OVERALL TREND WILL BE FOR SEAS TO
DIMINISH. SAT NIGHT INTO SUNDAY THE AXIS OF THE RIDGE WILL BOTH SINK
TO THE SOUTH AND ALSO PRETTY MUCH WASH OUT. THIS WILL TURN THE FLOW
BACK TO AN OFFSHORE DIRECTION. SEAS WILL REMAIN QUITE SMALL IN THE
ABSENCE OF ANY APPRECIABLE CHANGE IN WIND SPEEDS. A FAIRLY WEAK COLD
FRONT PUSHES THROUGH SUNDAY NIGHT TURNING WIND TO THE NORTH. THIS
BOUNDARY WILL BE FOLLOWED BY A STRONGER ONE THAT MAY LEAD TO QUITE A
SURGE IN WIND AND SEAS BY THE VERY END OF THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...GALE WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY AFTERNOON
FOR AMZ250-252-254-256.
&&
$$
SYNOPSIS...SHK
NEAR TERM...SHK
SHORT TERM...RJD
LONG TERM...MBB
AVIATION...SHK/DL
AREA FORECAST DISCUSSION
NWS BISMARCK ND
330 PM CST WED JAN 16 2013
.SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT...
THE MAIN CHALLENGE OF THE SHORT TERM WILL BE THE TIMING AND
INTENSITY OF PRECIPITATION THROUGH THURSDAY NIGHT.
RADAR RETURNS AT 20Z CONTINUE TO SHOW THE TREND OF DIMINISHING LIGHT
SNOW ACROSS PORTIONS OF THE EAST...WHILE THE WEST AND SOUTHWEST
REMAIN QUIET. THE LATEST RUN OF THE RAP AND THE 12Z NAM HAVE
INITIALIZED POORLY WHEN TAKING A LOOK AT CURRENT TRENDS. RADAR
RETURNS SUPPORT DIMINISHING LIGHT SNOW ACROSS MY EAST...HOWEVER IT
DOES NOT SUPPORT THE AREA OF PRECIPITATION ACROSS MY WEST AND
SOUTHWEST. AS A RESULT...HAVE OPTED TO BRING DOWN POPS/QPF
ESPECIALLY ACROSS THE SOUTHWEST AND WEST AND MENTIONED FLURRIES IN
THE WEATHER GRIDS.
ANOTHER IMPULSE WILL ENTER THE AREA THURSDAY AFTERNOON FROM THE
SOUTHERN MANITOBA AND SASKATCHEWAN AND MOVE SOUTHEAST ACROSS THE
NORTHWEST TO SOUTHEAST ORIENTED BAROCLINIC ZONE SET UP OVER NORTH
DAKOTA...GENERATING ANOTHER ROUND OF PRECIPITATION ACROSS NORTHERN
PORTIONS OF CENTRAL NORTH DAKOTA. PRECIPITATION TYPE SHOULD REMAIN
ALL SNOW AS MODEL SOUNDINGS FORECAST A TEMPERATURE PROFILE THAT
REMAINS BELOW FREEZING. SNOW ACCUMULATIONS ARE EXPECTED TO BE LIGHT
AND UNDER AN INCH.
.LONG TERM...FRIDAY THROUGH WEDNESDAY...
THE HIGHLIGHT OF THE EXTENDED FORECAST CONTINUES TO BE A POTENTIAL
ARCTIC SURGE SATURDAY INTO EARLY NEXT WEEK.
ONE LAST MILD DAY IS FORECAST ACROSS WESTERN AND CENTRAL NORTH
DAKOTA ON FRIDAY AS THE LOW LEVEL BAROCLINIC ZONE BENEATH THE POLAR
JET SHIFTS NORTHEAST WITH THE APPROACH OF THE NEXT CLIPPER SYSTEM.
WITH WESTERLY DOWNSLOPING WINDS OF 15-20 KTS...WIDESPREAD HIGHS IN
THE 30S ARE ANTICIPATED...WHICH MAY BE A BIT LOW FOR A FEW PLACES AS
THE SNOWPACK CONTINUES TO THIN. IN GENERAL...FOLLOWED A BLEND OF THE
DETERMINISTIC MODELS...AVOIDING THE NAM WHICH HAS SHOWN POOR
TEMPERATURE VERIFICATION AS OF LATE ON DAY 3.
FOR SATURDAY...THE AFOREMENTIONED CLIPPER PROPAGATES SOUTHEAST WITH
AN ASSOCIATED VERY STRONG COLD FRONT THAT WILL MARK THE BEGINNING OF
WHAT COULD BE THE COLDEST AIRMASS OF THE SEASON THUS FAR. WITH A
RATHER MILD CONDITIONS THROUGH FRIDAY NIGHT WITH LOW LEVEL MIXING
AHEAD OF THE FRONT...TEMPERATURES ARE LIKELY TO FALL THROUGH THE
ENTIRE DAY ACROSS THE AREA BEHIND THE FRONT. THE OTHER CONCERN FOR
SATURDAY IS THE STRONG WIND POTENTIAL. WHILE VERY STRONG ISALLOBARIC
FORCING IS FORECAST BEHIND THE FRONT WITH 15-20MB/6 HR PRESSURE
RISES WITH STRONG LOW LEVEL COLD AIR ADVECTION...THE BIG QUESTION
ONCE AGAIN IS LOW LEVEL LAPSES RATES AND HOW HIGH MOMENTUM CAN BE
TRANSFERRED FROM....WHICH IS VARIED AMONGST THE DETERMINISTIC MODELS.
WHILE WIND ADVISORY LEVEL GUSTS ARE PROBABLE GIVEN CURRENT
TRENDS...SHOULD NEAR ADIABATIC LAPSE RATES BE ESTABLISHED THROUGH
850 MB...50+ KTS COULD BE MIXED TO THE SURFACE.
THE OVERALL 12 UTC GUIDANCE SUITE IS IN GOOD AGREEMENT IN THE
DEVELOPMENT OF A HIGH AMPLITUDE UPPER LEVEL RIDGE ALONG THE PACIFIC
COAST AND INTO THE ARCTIC THROUGH SUNDAY AND INTO NEXT WEEK...WHICH
SHOULD ALLOW VERY COLD ARCTIC AIR TO BE TRANSPORTED SOUTH UNDER DEEP
CYCLONIC FLOW ALOFT. THE COLDEST TIMEFRAME APPEARS TO BE SUNDAY
THROUGH MONDAY NIGHT AS A NEAR 1045 MB SURFACE HIGH ON THE
DETERMINISTIC MODELS BRINGS A REINFORCING SHOT OF COLD AIR TO THE
AREA.GIVEN GOOD AGREEMENT...WILL UTILIZE A BLEND OF THE
GUIDANCE...WHICH RESULTS IN WIDESPREAD LOWS SUNDAY NIGHT OF -15 TO
-25 WITH SUB-ZERO DAYTIME HIGHS ON MONDAY. WIND CHILL TEMPERATURES
COLDER THAN -40 ARE NOT OUT OF THE QUESTION. SHOULD TRENDS
CONTINUE...A WIND CHILL WATCH MAY BE NECESSARY. THE QUESTION BECOMES
LATE MONDAY AND INTO TUESDAY OF WHETHER THE LOW LEVEL ARCTIC AIRMASS
CAN SCOURED OUT...OR IF WARMING AHEAD OF LEE TROUGHING WILL NOT BE
REALIZED AT THE SURFACE. THE 12 UTC GFS APPEARING TO BE THE MOST
AGGRESSIVE AT GETTING RID OF THE ARCTIC AIR...WHICH IS QUESTIONABLE
COMPARED TO ITS OWN ENSEMBLE MEAN AND THE GEM/ECMWF.
&&
.AVIATION...
AS OF 21 UTC...A COLD FRONT WAS LOCATED FROM KISN THROUGH KBIS AND
KABR. THIS FRONT SHOULD SOON STALL OUT ACROSS SOUTHWEST NORTH
DAKOTA. SNOW FROM THIS MORNING HAS GENERALLY
DISSIPATED...HOWEVER...ISOLATED VERY LIGHT SNOW SHOWERS ARE STILL
POSSIBLE THROUGH 00 UTC. THE PREDOMINANT FLIGHT CATEGORY ACROSS
WESTERN AND CENTRAL NORTH DAKOTA THROUGH THE AFTERNOON AND MUCH OF
THE NIGHT SHOULD BE MVFR IN STRATUS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...HUBER
LONG TERM/AVIATION...AYD
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
1011 AM CST WED JAN 16 2013
.DISCUSSION...
OVERALL...FORECAST IS IN GOOD SHAPE. ADJUSTED HIGHEST POPS A BIT
FARTHER SOUTH ALONG BAND OF LIGHT SNOW STRETCHING FROM BOTTINEAU
TO BETWEEN FARGO AND WAHPETON. THIS AREA OF SNOW EXPECTED TO SAG
SOUTH AND EAST THROUGH THE DAY ALONG STRONGEST MID-LEVEL THERMAL
GRADIENT. ACCUMULATIONS SHOULD BE AN INCH OR LESS. SNOW SHOULD
EXIT THE FORECAST AREA BY 00 UTC TONIGHT.
SURFACE COLD FRONT HAS MOVED SOUTH AND WEST OF THE FORECAST AREA
AND WITH STRONG COLD AIR ADVECTION...EXPECT TEMPERATURES TO FALL
THROUGH THE DAY. MOST LOCATIONS NORTH OF THE HIGHWAY 2 CORRIDOR
WILL FALL BELOW ZERO BY 6 PM THIS EVENING. AFTERNOON BOUNDARY
LAYER DEEPENS TO BETWEEN 900 AND 950 HPA WITH AROUND 20 KTS TO MIX
TO THE SURFACE...SO WILL SEE NORTHERLY WIND FROM 10 TO 15 MPH.
SHOULD SEE SOME GRADUAL CLEARING ACROSS THE NORTHEAST LATE IN THE
DAY... BUT DID INCREASE SKY COVER THIS MORNING AND EARLY AFTERNOON
REGION- WIDE GIVEN UPSTREAM CLOUD COVER.
&&
.AVIATION...
CIGS SHOULD IMPROVE AS IFR/MVFR CONDITIONS ERODE WITH DRIER
NORTHERLY WINDS AT ALL TAF SITES. ANY STRONG GUSTS THIS MORNING
WILL DIMINISH DURING THE LATER HALF OF THE DAY WITH SFC HIGH
BUILDING IN TO THE REGION. SNOW BAND MAY CLIP THE DVL AND FAR TAF
SITES THROUGH EARLY AFTN...MAY CAUSE VSBY/CIGS TO DROP FOR A
BRIEF PERIOD.
&&
.PREV DISCUSSION... /ISSUED 636 AM CST WED JAN 16 2013/
UPDATE...
UPDATED FOR A EASTWARD TREND OF -SN ACROSS THE LANGDON TO GFK TO
PARK RAPIDS LINE. ALSO COOLED TEMPS THIS MORNING ACROSS THE NORTH
AS TEMPS IN THE SINGLE DIGITS ENTERING INT EH NORTHERN VALLEY
ALREADY. LATEST RAP MODEL RUN HANDLED THESE TRENDS VERY WELL USED
IT FOR THE REST OF THE MORNING AND INTO EARLY AFTN OF PCPN
PLACEMENT.
PREV DISCUSSION... /ISSUED 340 AM CST WED JAN 16 2013/
SHORT TERM...
THE CHALLENGES FOR THE FORECAST THIS MORNING INCLUDE THE TIMING OF
FRONTAL PASSAGES AND ASSOCIATED PCPN/CLOUD COVER AND AND ITS
EFFECT ON TEMPERATURES. MODELS IN REASONABLE AGREEMENT WITH GENERAL
FEATURES THROUGH THE END OF THE WEEK AND WILL USE A BLEND FOR THE
FORECAST PACKAGE.
COLD FRONT CURRENTLY PUSHING ACROSS THE CWFA WITH A STRONG PUSH OF
CAA IN ITS WAKE. AHEAD OF THE WIND SHIFT TO THE NORTH TEMPS HAVE
PUSHED INTO THE MID 30S VALLEY AND WEST. SAFE TO SAY TODAYS HIGHS
HAVE BEEN REACHED AND TEMPS WILL FALL FOR THE REST OF THE DAY AS
925MB TEMPS DROP 10 TO 20 C BY 00Z THURS. SOME -SN IS LIKELY ACROSS
THE SW PORTION OF THE CWFA AS A WEAK IMPULSE MOVES SE ALONG THE
BAROCLINIC ZONE AND UNDER THE 300MB RIGHT EXIT REGION. EXPECT AN
INCH OR TWO ALONG AND SOUTH OF A LINE FROM DVL TO W CASS TO ELBOW
LAKE.
SFC HIGH PRESSURE SLIDES ACROSS THE REGION TONIGHT AND TEMPS WILL
BE HIGHLY DEPENDENT ON CLOUD COVER WITH THE COLDEST VALUES
EXPECTED ACROSS THE NW MN... NEAR ZERO IN THE FAR WEST TO ALMOST
20 BELOW IN THE N RRV AND ROX TO BDE AREAS. A SLOW RECOVERY
EXPECTED THURSDAY AS WEAK MIXING AND THE COLD COLUMN LIMIT
WARMING.
RETURN FLOW AHEAD OF THE NEXT SW IN THE NW FLOW BEGINS THURSDAY PM
AND SHOULD LIMIT TEMP DROP OFF ACROSS E ND AS CLOUDS/-SN IN THE
WAA MOVES INTO THE FA. SFC LOW TRACK ALONG AND SOUTH OF THE
INTERNATIONAL BORDER WILL KEEP BEST CHC FOR -SN ALONG THE
INTERNATIONAL BORDER AREAS TO BEMIDJI FRIDAY WITH WEST WINDS
ALLOWING FOR SOME WARMING ACROSS SE ND FRIDAY AFTN. COLD FRONT
PUSHES THROUGH OVERNIGHT WITH FALLING TEMPS EXPECTED DURING THE
DAY SATURDAY.
LONG TERM (SAT-TUE)... A COLD PERIOD COMING UP AS ALL LONG RANGE
MODELS SHOW THE POLAR LOW OVER HUDSON BAY. SEVERAL SHORT WAVES
WILL CONTINUE TO MOVE SOUTHEAST...ONE WILL MOVE THRU SUNDAY
FOLLOWED BY HIGH PRESSURE AND LIKELY THE COLDEST OF THE AIRMASSES
THIS WINTER SEASON FOR SUN NIGHT INTO TUESDAY. EXPECT TEMPS TO
REMAIN BLO ZERO SUN-TUE. WITH HIGH OVERHEAD AND LIKELY A CLEAR
SKY SHOULD HAVE WIDESPREAD -20S SUN NIGHT AND AGAIN MON
NIGHT...COLDEST IN THE NORTH AND EASTERN PARTS OF THE FCST AREA.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
ROGERS/JK
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1146 AM CST WED JAN 16 2013
.DISCUSSION.../ISSUED AT 1045 AM CST/
A MILD AFTERNOON IS IN STORE ACROSS THE AREA...ESPECIALLY AS YOU
HEAD SOUTH TOWARDS THE MISSOURI RIVER. WENT AHEAD AND BUMPED UP
HIGHS A COUPLE TO SEVERAL DEGREES ACROSS THE AREA...WITH MID AND
EVEN A FEW UPPER 40S POSSIBLE FROM SIOUX CITY WEST TO GREGORY.
CLOUDS INCREASING ACROSS OUR NORTH...WITH PARTLY TO MOSTLY SUNNY
SKIES CONTINUING IN THE SOUTH. BACKDOOR COLD FRONT CURRENTLY
DROPPING SOUTH OUT OF WESTERN MINNESOTA AND NORTHEAST SOUTH DAKOTA.
WILL LIKELY SEE TEMPERATURES DROP QUICKLY INTO THE 20S AND TEENS
BEHIND THIS FRONT FROM NORTH TO SOUTH. LATEST RAP WOULD SUGGEST
FRONT PASSES THROUGH THE HIGHWAY 14 CORRIDOR NEAR 22Z...INTERSTATE
90 AROUND 0Z...AND OUR SOUTHERN COUNTIES CLOSER TO 3Z. COLDEST AIR
WILL ONLY CLIP OUR AREA...WITH THE BRUNT OF IT STAYING TO OUR EAST.
WATCHING SOME LIGHT SNOW BEHIND SURFACE FRONT ASSOCIATED WITH MID
LEVEL FRONTOGENESIS. BASED ON RADAR AND MODEL FORECASTS THINK MOST
OF THIS WILL STAY TO OUR NORTHEAST...ALTHOUGH COULD CLIP AREAS FROM
BROOKINGS TO MARSHALL WITH SOME LIGHT SNOW OF A COUPLE TENTHS.
ELSEWHERE....ALONG AND NORTH OF INTERSTATE 90 MAINLY JUST THINKING
SOME FLURRIES AT MOST. /CHENARD
.PREVIOUS DISCUSSION.../ISSUED AT 340 AM CST/
WEAK UPPER LEVEL SUPPORT WILL SPREAD ACROSS THE AREA
TODAY...CREATING CLOUD COVER BUT LITTLE INT HE WAY OF SNOWFALL. JUST
ENOUGH LOWER TO MID LEVEL MOISTURE WILL EXIST HOWEVER THAT FLURRIES
AND SOME LIGHT SNOW WILL BE POSSIBLE IN THE NORTHEAST HALF OF THE
CWA. PARTS OF SOUTHWEST MINNESOTA COULD RECEIVE A COUPLE OF TENTHS
OF AN INCH. OTHERWISE...TEMPERATURES HAVE WARMED QUITE A BIT
OVERNIGHT WITH A NICE MIXING WESTERLY WIND AHEAD OF THE COLDER DRIER
AIR EXPECTED TO ADVECT INTO THE AREA FROM THE NORTH. THIS WILL ALLOW
FOR A MILD DAY ACROSS THE AREA EVEN WITH CLOUD COVER...WITH HIGHS
RANGING FROM THE MID 30S IN SOUTHWEST MINNESOTA TO 40 TO 45 ALONG
THE MISSOURI RIVER.
A WEAK RIDGE OF COLD HIGH PRESSURE WILL SETTLE SOUTH TONIGHT WHICH
WILL ALLOW FOR SOME COLD OVERNIGHT LOW TEMPERATURES. WINDS WILL NOT
BE EXCESSIVE OVERNIGHT...BUT COULD DROP WIND CHILL VALUES TO 5 TO 10
BELOW ZERO OVER PARTS OF SOUTHWEST MINNESOTA. SNOWFALL IS NOT
EXPECTED AS SUBSIDENCE FILLS IN BEHIND TODAYS UPPER LEVEL WAVE. LOWS
OVERNIGHT WILL RANGE FROM AROUND 5 ABOVE IN SOUTHWEST MINNESOTA TO
NEAR 20 ALONG THE MISSOURI RIVER.
MIXING WILL BE A BIT LIMITED ON THURSDAY AS A RIDGE OF HIGH PRESSURE
REMAINS IN PLACE OVER THE EASTERN PART OF THE CWA. THIS WILL KEEP
TEMPERATURES A LITTLE COLDER...BUT STILL CLOSE TO NORMAL OVER
SOUTHWEST MINNESOTA...MAINLY IN THE MID 20S. FARTHER SOUTH AND WEST
TEMPERATURES WILL REBOUND A BIT AND CLIMB TO 35 TO 40 DEGREES.
THURSDAY NIGHT INTO FRIDAY WILL SEE A MILD AIR MASS DEVELOP WITH
SOUTHERLY WIND FRIDAY NIGHT...BECOMING WESTERLY ON FRIDAY. THIS IS
OF COURSE A FAVORABLE WIND DIRECTION SO EXPECT MORNING LOWS IN THE
TEENS AND FRIDAY HIGHS FROM ABOUT 35 TO 45 DEGREES.
IN THE LATTER PERIODS (SAT/TUE)...SATURDAY LIKELY TO BE THE LAST
MILD DAY FOR AWHILE...AND EVEN THAT IS A LITTLE QUESTIONABLE AS ALL
OF THE MODELS HAVE A COLD FRONT SURGING THROUGH BETWEEN 18Z AND 0Z
SO ANY MINOR INCREASE IN SPEED AND SATURDAY WILL BE MUCH COLDER. A
SLIGHT MODERATION IN TEMPERATURES ON SUNDAY AS A WAVE MOVES NORTH OF
THE AREA WHICH WILL BRIEFLY LIGHTEN WINDS OR TURN THEM A BIT
SOUTHERLY THEN DRAG DOWN THE COLDEST AIR OF THE SEASON SUNDAY NIGHT.
SOME DIFFERENCES IN SPEED BUT NOT MUCH DIFFERENCE IN HOW COLD BEHIND
THE FRONT SO SOME CONFIDENCE IN OVERALL TEMPERATURE FORECAST SUNDAY
THROUGH TUESDAY...WHICH WILL BE QUITE A BIT BELOW NORMAL. IF
EVERYTHING PANS OUT MORE THAN LIKELY WILL SEE A PERIOD OF LIGHT SNOW
ON SUNDAY THEN EITHER A WIND CHILL ADVISORY OR WIND CHILL WARNING
SUNDAY NIGHT THROUGH MONDAY EVENING. HIGH PRESSURE IS EXPECTED TO
BUILD SOUTH ON MONDAY NIGHT SO WINDS WILL GO LIGHT AND IF THERE IS
ANY FRESH SNOW COVER TUESDAY MORNING LOWS WILL BE QUITE COLD. /08
&&
.AVIATION.../FOR THE 18Z TAF ISSUANCE/
CURRENTLY SEEING AN AREA OF MVFR CIGS ACROSS SOUTHWEST
MINNESOTA...WITH VFR ELSEWHERE. THIS AREA IS PUSHING OFF TO THE
SOUTHEAST WITH IMPROVING CONDITIONS OVER THE NEXT FEW HOURS.
HOWEVER...A BACKDOOR COLD FRONT IS PUSHING SOUTH OUT OF NORTH DAKOTA
AND MINNESOTA. MAIN ADJUSTMENTS TO PREVIOUS FORECAST WAS TO SPEED UP
TIMING OF THUS FRONT AND ASSOCIATED MVFR STRATUS BY ABOUT AN
HOUR...AND KEEP MVFR CIGS INTO TOMORROW MORNING. TOUGH CALL ON THE
LATTER THOUGH. INITIAL SURGE OF MVFR AND POSSIBLY ISOLATED IFR CIGS
BEHIND THE FRONT WILL PUSH SOUTH TONIGHT. SOME LOW LEVEL DRYING
LIKELY BEHIND THIS...HOWEVER AS BOUNDARY LAYER FLOW BECOMES WEAK
WESTERLY TEND TO THINK MORE STRATUS MOVES IN OR LINGERS. THINK THERE
MAY BE SOME VFR PERIODS...BUT THE PREDOMINATE CIG MAY VERY WELL BE
MVFR THROUGH TOMORROW MORNING. AGAIN THIS IS LOW CONFIDENCE...WITH
ANYWHERE FROM IFR TO VFR POSSIBLE LATER TONIGHT INTO TOMORROW
MORNING. /CHENARD
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1046 AM CST WED JAN 16 2013
.DISCUSSION.../ISSUED AT 1045 AM CST/
A MILD AFTERNOON IS IN STORE ACROSS THE AREA...ESPECIALLY AS YOU
HEAD SOUTH TOWARDS THE MISSOURI RIVER. WENT AHEAD AND BUMPED UP
HIGHS A COUPLE TO SEVERAL DEGREES ACROSS THE AREA...WITH MID AND
EVEN A FEW UPPER 40S POSSIBLE FROM SIOUX CITY WEST TO GREGORY.
CLOUDS INCREASING ACROSS OUR NORTH...WITH PARTLY TO MOSTLY SUNNY
SKIES CONTINUING IN THE SOUTH. BACKDOOR COLD FRONT CURRENTLY
DROPPING SOUTH OUT OF WESTERN MINNESOTA AND NORTHEAST SOUTH DAKOTA.
WILL LIKELY SEE TEMPERATURES DROP QUICKLY INTO THE 20S AND TEENS
BEHIND THIS FRONT FROM NORTH TO SOUTH. LATEST RAP WOULD SUGGEST
FRONT PASSES THROUGH THE HIGHWAY 14 CORRIDOR NEAR 22Z...INTERSTATE
90 AROUND 0Z...AND OUR SOUTHERN COUNTIES CLOSER TO 3Z. COLDEST AIR
WILL ONLY CLIP OUR AREA...WITH THE BRUNT OF IT STAYING TO OUR EAST.
WATCHING SOME LIGHT SNOW BEHIND SURFACE FRONT ASSOCIATED WITH MID
LEVEL FRONTOGENESIS. BASED ON RADAR AND MODEL FORECASTS THINK MOST
OF THIS WILL STAY TO OUR NORTHEAST...ALTHOUGH COULD CLIP AREAS FROM
BROOKINGS TO MARSHALL WITH SOME LIGHT SNOW OF A COUPLE TENTHS.
ELSEWHERE....ALONG AND NORTH OF INTERSTATE 90 MAINLY JUST THINKING
SOME FLURRIES AT MOST. /CHENARD
.PREVIOUS DISCUSSION.../ISSUED AT 340 AM CST/
WEAK UPPER LEVEL SUPPORT WILL SPREAD ACROSS THE AREA
TODAY...CREATING CLOUD COVER BUT LITTLE INT HE WAY OF SNOWFALL. JUST
ENOUGH LOWER TO MID LEVEL MOISTURE WILL EXIST HOWEVER THAT FLURRIES
AND SOME LIGHT SNOW WILL BE POSSIBLE IN THE NORTHEAST HALF OF THE
CWA. PARTS OF SOUTHWEST MINNESOTA COULD RECEIVE A COUPLE OF TENTHS
OF AN INCH. OTHERWISE...TEMPERATURES HAVE WARMED QUITE A BIT
OVERNIGHT WITH A NICE MIXING WESTERLY WIND AHEAD OF THE COLDER DRIER
AIR EXPECTED TO ADVECT INTO THE AREA FROM THE NORTH. THIS WILL ALLOW
FOR A MILD DAY ACROSS THE AREA EVEN WITH CLOUD COVER...WITH HIGHS
RANGING FROM THE MID 30S IN SOUTHWEST MINNESOTA TO 40 TO 45 ALONG
THE MISSOURI RIVER.
A WEAK RIDGE OF COLD HIGH PRESSURE WILL SETTLE SOUTH TONIGHT WHICH
WILL ALLOW FOR SOME COLD OVERNIGHT LOW TEMPERATURES. WINDS WILL NOT
BE EXCESSIVE OVERNIGHT...BUT COULD DROP WIND CHILL VALUES TO 5 TO 10
BELOW ZERO OVER PARTS OF SOUTHWEST MINNESOTA. SNOWFALL IS NOT
EXPECTED AS SUBSIDENCE FILLS IN BEHIND TODAYS UPPER LEVEL WAVE. LOWS
OVERNIGHT WILL RANGE FROM AROUND 5 ABOVE IN SOUTHWEST MINNESOTA TO
NEAR 20 ALONG THE MISSOURI RIVER.
MIXING WILL BE A BIT LIMITED ON THURSDAY AS A RIDGE OF HIGH PRESSURE
REMAINS IN PLACE OVER THE EASTERN PART OF THE CWA. THIS WILL KEEP
TEMPERATURES A LITTLE COLDER...BUT STILL CLOSE TO NORMAL OVER
SOUTHWEST MINNESOTA...MAINLY IN THE MID 20S. FARTHER SOUTH AND WEST
TEMPERATURES WILL REBOUND A BIT AND CLIMB TO 35 TO 40 DEGREES.
THURSDAY NIGHT INTO FRIDAY WILL SEE A MILD AIR MASS DEVELOP WITH
SOUTHERLY WIND FRIDAY NIGHT...BECOMING WESTERLY ON FRIDAY. THIS IS
OF COURSE A FAVORABLE WIND DIRECTION SO EXPECT MORNING LOWS IN THE
TEENS AND FRIDAY HIGHS FROM ABOUT 35 TO 45 DEGREES.
IN THE LATTER PERIODS (SAT/TUE)...SATURDAY LIKELY TO BE THE LAST
MILD DAY FOR AWHILE...AND EVEN THAT IS A LITTLE QUESTIONABLE AS ALL
OF THE MODELS HAVE A COLD FRONT SURGING THROUGH BETWEEN 18Z AND 0Z
SO ANY MINOR INCREASE IN SPEED AND SATURDAY WILL BE MUCH COLDER. A
SLIGHT MODERATION IN TEMPERATURES ON SUNDAY AS A WAVE MOVES NORTH OF
THE AREA WHICH WILL BRIEFLY LIGHTEN WINDS OR TURN THEM A BIT
SOUTHERLY THEN DRAG DOWN THE COLDEST AIR OF THE SEASON SUNDAY NIGHT.
SOME DIFFERENCES IN SPEED BUT NOT MUCH DIFFERENCE IN HOW COLD BEHIND
THE FRONT SO SOME CONFIDENCE IN OVERALL TEMPERATURE FORECAST SUNDAY
THROUGH TUESDAY...WHICH WILL BE QUITE A BIT BELOW NORMAL. IF
EVERYTHING PANS OUT MORE THAN LIKELY WILL SEE A PERIOD OF LIGHT SNOW
ON SUNDAY THEN EITHER A WIND CHILL ADVISORY OR WIND CHILL WARNING
SUNDAY NIGHT THROUGH MONDAY EVENING. HIGH PRESSURE IS EXPECTED TO
BUILD SOUTH ON MONDAY NIGHT SO WINDS WILL GO LIGHT AND IF THERE IS
ANY FRESH SNOW COVER TUESDAY MORNING LOWS WILL BE QUITE COLD. /08
&&
.AVIATION.../FOR THE 12Z TAF ISSUANCE/
BAND OF MVFR CEILINGS AND GENERALLY VFR VISIBILITY WITH FLURRIES
WILL CONTINUE TO PROGRESS THROUGH SOUTHEAST HALF OF THE FORECAST
AREA EARLY THIS MORNING. POTENTIAL FOR MVFR CONDITIONS SHOULD PASS
THROUGH KSUX FOR FIRST COUPLE HOURS OF THIS TAF PERIOD...OTHERWISE
EXPECTING VFR CONDITIONS TO PREVAIL AT TAF LOCATIONS UNTIL LATE THIS
AFTERNOON BEHIND COLD FRONT WHICH WILL PUSH BACK SOUTH THROUGH THE
REGION. PERIODS OF MVFR CEILINGS MORE LIKELY TO LINGER IN SOUTHWEST
MINNESOTA ALONG/EAST OF THE BUFFALO RIDGE THIS MORNING...WITH MVFR
AND EVEN SOME IFR CEILINGS SPREADING BACK ACROSS THE FORECAST AREA
NORTH TO SOUTH DURING THE LATE AFTERNOON/EVENING BEHIND THE COLD
FRONT.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1140 AM CST WED JAN 16 2013
.SHORT TERM...THROUGH THIS EVENING
1026 AM CST WED JAN 16 2013
UPDATED FORECAST TO EXTEND FREEZING DRIZZLE / LIGHT SNOW ACROSS
THE EASTERN FORECAST AREA THROUGH NOON AS POCKETS OF PRECIPITATION
CONTINUE TO MOVE EAST. DUAL POL RETURNS SUGGEST THE MAJORITY OF
THE PRECIPITATION IS LIGHT SNOW...BUT IN BETWEEN THE POCKETS OF
HIGHER REFLECT IVIES...THE PTYPE MAY BE A LIGHT MIST OR DRIZZLE.
THIS HAS CAUSED SLICK SPOTS WITH SOME ACCIDENTS ACROSS THE AREA.
THE FOCUS FOR THE PRECIPITATION IS THE SURFACE BOUNDARY DRAPED JUST
OFF TO THE NORTHWEST...AND THIS WILL MOVE THROUGH DURING THE
AFTERNOON HOURS.
FOR LATE THIS AFTERNOON INTO THE EARLY EVENING...A SECONDARY
SHORTWAVE TROUGH DIPS THROUGH THE FLOW AND INTERACTS SOMEWHAT
WITH THE LINGERING SURFACE BOUNDARY FROM THIS MORNING. UPSTREAM
OBSERVATIONS SHOW 1 TO 2SM LIGHT SNOW ACROSS THE EASTERN DAKOTAS
AND THIS PRECIPITATION WILL SLIDE SOUTH/EAST...ARRIVING IN THE
NORTHWEST FORECAST AREA BY MID AFTERNOON. HAVE INCREASED CHANCES
ACROSS MOST OF THE AREA...WITH THE IDEA THAT THE ACTIVITY WILL BE
MAINLY LIGHT WITH ONLY 1/10 TO 3/10 OF AN INCH OF SNOW EXPECTED.
HOWEVER...TIMING WILL BE RIGHT AROUND THE EVENING COMMUTE SO THERE
COULD BE SOME TRAVEL CONCERNS AS PEOPLE HEAD HOME FROM WORK AND
SCHOOL. SOUNDINGS LOOK TO SUPPORT ALL SNOW...SO HAVE NOT
INTRODUCED ANY FREEZING DRIZZLE AT THIS TIME. THE HIGHER CHANCES
LOOK TO BE ALONG AND WEST OF THE MISSISSIPPI RIVER AND THE LATEST
HI-RES MESO MODELS AND THE 16.15Z RAP HANDLE THIS FAIRLY WELL...SO
HAVE TRENDED TOWARD THEIR SOLUTIONS.
.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
355 AM CST WED JAN 16 2013
ON FRIDAY NIGHT...A COLD FRONT WILL BRIEFLY SURGE SOUTHWARD INTO
THE AREA AND THEN MOVE BACK NORTH AS A WARM FRONT AS A LOW
PRESSURE SYSTEM MOVES INTO NORTHWEST MINNESOTA. THE 275-285K
ISENTROPIC SURFACES SHOW THAT IT WILL TAKE 50 TO 100 MB FOR
SATURATION TO OCCUR. AS A RESULT...KEPT THE FORECAST DRY FOR NOW.
HIGH TEMPERATURES ON SATURDAY WILL RANGE FROM THE MID 20S TO MID 30S.
FROM LATE SATURDAY AFTERNOON INTO SATURDAY NIGHT...AN ARCTIC COLD
FRONT WILL MOVE SOUTH THROUGH THE FORECAST AREA. THE BEST MOISTURE
AND LIFT LOOKS TO BE MAINLY ALONG AND NORTH OF THE INTERSTATE 94
CORRIDOR. DUE TO THIS...KEPT LIGHT SNOW CHANCES MAINLY CONFINED
TO THIS AREA. LIKE LAST NIGHT...THE MODEL SOUNDINGS CONTINUE TO
SUGGEST THAT THE WINDS MAY BRIEFLY GUST INTO THE 35 TO 45 MPH
RANGE IN THE WAKE OF THIS FRONT.
ON SUNDAY NIGHT AND MONDAY MORNING...THE MODELS CONTINUE TO SHOW
THAT ANOTHER ARCTIC COLD FRONT WILL MOVE SOUTH THROUGH THE REGION.
THE GEM...GFS...AND ECMWF SUGGEST THAT SOME LIGHT SNOW WILL BE
ASSOCIATED WITH THIS FRONTAL PASSAGE. 850 MB TEMPERATURES ARE
AROUND 1.5 STANDARD DEVIATIONS BELOW NORMAL IN THE GFS AND AROUND
2 STANDARD DEVIATIONS BELOW NORMAL IN THE ECMWF. IT LOOKS LIKE
MUCH OF THE AREA WILL SEE HIGH TEMPERATURES REMAINING IN THE
SINGLE DIGITS. WIND CHILLS ON THIS MORNING LOOK TO BE IN THE 10 TO
20 BELOW RANGE.
ON MONDAY NIGHT...THE MODELS CONTINUE TO SHOW THAT LOW TEMPERATURES
WILL LIKELY RANGE FROM 5 TO 20 BELOW. WITH TEMPERATURES THIS COLD...
ANY WIND AT ALL WILL PRODUCE WIND CHILLS IN THE ADVISORY CRITERIA
/20 TO 35 BELOW/.
EARLY NEXT WEEK...THE MODELS CONTINUE TO SHOW THAT A STRONG SUDDEN
STRATOSPHERIC WARMING EVENT WILL TAKE PLACE ACROSS THE NORTH
CENTRAL PACIFIC. THIS WILL RESULT IN A LONG WAVE TROUGH QUICKLY
DEVELOPING ACROSS THIS AREA. THIS IS TURN WILL GIVE AN EASTERN
NUDGE TO THE LONG WAVE RIDGE ACROSS THE EAST PACIFIC AND WESTERN
NORTH AMERICA. AS THIS OCCURS...THE COLDEST AIR SHOULD START TO
SHIFT OUT OF THE AREA ON TUESDAY AND TUESDAY NIGHT. BOTH THE
DETERMINISTIC AND ENSEMBLE MEMBERS SHOW THIS OCCURRING...SO
CONFIDENCE IS FAIRLY HIGH THAT THIS LATEST BOUT OF ARCTIC AIR WILL
BE A SHORT LIVED.
&&
.AVIATION...THROUGH 18Z THURSDAY
1140 AM CST WED JAN 16 2013
A BRIEF PERIOD OF IMPROVED CONDITIONS EARLY THIS AFTERNOON AT
KRST/KLSE BEFORE ANOTHER SHORTWAVE TROUGH DIPS DOWN...BRINGING
LIGHT SNOW ALONG WITH A WIND SHIFT TO THE NORTHWEST. THIS WAVE
CURRENTLY BRINGING 1SM OR LESS VISIBILITIES WITH IFR
CEILINGS...AND TIMING PUTS THIS SNOW BAND AT KRST AROUND
20Z...AND 21Z AT KLSE. CEILINGS AND VISIBILITIES WILL BOUNCE AROUND
FOR A PERIOD LATE THIS AFTERNOON SO HAVE INCLUDED A TEMPO GROUP TO
REFLECT THIS. THE SYSTEM WILL BEGIN TO PUSH AWAY FROM THE TAF
SITES BETWEEN 01 AND 02Z. AFTER THAT...CONFIDENCE IS LOW ON
CEILINGS BUT HAVE REMAINED PESSIMISTIC WITH A MVFR DECK THROUGH
THE NIGHT. THERE REMAINS A CHANCE THAT CLOUDS WILL SCATTER OUT...BUT
THINK THAT WILL BE A SHORT-LIVED OPPORTUNITY BEFORE ADDITIONAL
CLOUDS STREAM IN.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
355 AM CST WED JAN 16 2013
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...ZT
LONG TERM...BOYNE
AVIATION...ZT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1026 AM CST WED JAN 16 2013
.SHORT TERM...THROUGH THIS EVENING
1026 AM CST WED JAN 16 2013
UPDATED FORECAST TO EXTEND FREEZING DRIZZLE / LIGHT SNOW ACROSS
THE EASTERN FORECAST AREA THROUGH NOON AS POCKETS OF PRECIPITATION
CONTINUE TO MOVE EAST. DUAL POL RETURNS SUGGEST THE MAJORITY OF
THE PRECIPITATION IS LIGHT SNOW...BUT IN BETWEEN THE POCKETS OF
HIGHER REFLECT IVIES...THE PTYPE MAY BE A LIGHT MIST OR DRIZZLE.
THIS HAS CAUSED SLICK SPOTS WITH SOME ACCIDENTS ACROSS THE AREA.
THE FOCUS FOR THE PRECIPITATION IS THE SURFACE BOUNDARY DRAPED JUST
OFF TO THE NORTHWEST...AND THIS WILL MOVE THROUGH DURING THE
AFTERNOON HOURS.
FOR LATE THIS AFTERNOON INTO THE EARLY EVENING...A SECONDARY
SHORTWAVE TROUGH DIPS THROUGH THE FLOW AND INTERACTS SOMEWHAT
WITH THE LINGERING SURFACE BOUNDARY FROM THIS MORNING. UPSTREAM
OBSERVATIONS SHOW 1 TO 2SM LIGHT SNOW ACROSS THE EASTERN DAKOTAS
AND THIS PRECIPITATION WILL SLIDE SOUTH/EAST...ARRIVING IN THE
NORTHWEST FORECAST AREA BY MID AFTERNOON. HAVE INCREASED CHANCES
ACROSS MOST OF THE AREA...WITH THE IDEA THAT THE ACTIVITY WILL BE
MAINLY LIGHT WITH ONLY 1/10 TO 3/10 OF AN INCH OF SNOW EXPECTED.
HOWEVER...TIMING WILL BE RIGHT AROUND THE EVENING COMMUTE SO THERE
COULD BE SOME TRAVEL CONCERNS AS PEOPLE HEAD HOME FROM WORK AND
SCHOOL. SOUNDINGS LOOK TO SUPPORT ALL SNOW...SO HAVE NOT
INTRODUCED ANY FREEZING DRIZZLE AT THIS TIME. THE HIGHER CHANCES
LOOK TO BE ALONG AND WEST OF THE MISSISSIPPI RIVER AND THE LATEST
HI-RES MESO MODELS AND THE 16.15Z RAP HANDLE THIS FAIRLY WELL...SO
HAVE TRENDED TOWARD THEIR SOLUTIONS.
.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
355 AM CST WED JAN 16 2013
ON FRIDAY NIGHT...A COLD FRONT WILL BRIEFLY SURGE SOUTHWARD INTO
THE AREA AND THEN MOVE BACK NORTH AS A WARM FRONT AS A LOW
PRESSURE SYSTEM MOVES INTO NORTHWEST MINNESOTA. THE 275-285K
ISENTROPIC SURFACES SHOW THAT IT WILL TAKE 50 TO 100 MB FOR
SATURATION TO OCCUR. AS A RESULT...KEPT THE FORECAST DRY FOR NOW.
HIGH TEMPERATURES ON SATURDAY WILL RANGE FROM THE MID 20S TO MID 30S.
FROM LATE SATURDAY AFTERNOON INTO SATURDAY NIGHT...AN ARCTIC COLD
FRONT WILL MOVE SOUTH THROUGH THE FORECAST AREA. THE BEST MOISTURE
AND LIFT LOOKS TO BE MAINLY ALONG AND NORTH OF THE INTERSTATE 94
CORRIDOR. DUE TO THIS...KEPT LIGHT SNOW CHANCES MAINLY CONFINED
TO THIS AREA. LIKE LAST NIGHT...THE MODEL SOUNDINGS CONTINUE TO
SUGGEST THAT THE WINDS MAY BRIEFLY GUST INTO THE 35 TO 45 MPH
RANGE IN THE WAKE OF THIS FRONT.
ON SUNDAY NIGHT AND MONDAY MORNING...THE MODELS CONTINUE TO SHOW
THAT ANOTHER ARCTIC COLD FRONT WILL MOVE SOUTH THROUGH THE REGION.
THE GEM...GFS...AND ECMWF SUGGEST THAT SOME LIGHT SNOW WILL BE
ASSOCIATED WITH THIS FRONTAL PASSAGE. 850 MB TEMPERATURES ARE
AROUND 1.5 STANDARD DEVIATIONS BELOW NORMAL IN THE GFS AND AROUND
2 STANDARD DEVIATIONS BELOW NORMAL IN THE ECMWF. IT LOOKS LIKE
MUCH OF THE AREA WILL SEE HIGH TEMPERATURES REMAINING IN THE
SINGLE DIGITS. WIND CHILLS ON THIS MORNING LOOK TO BE IN THE 10 TO
20 BELOW RANGE.
ON MONDAY NIGHT...THE MODELS CONTINUE TO SHOW THAT LOW TEMPERATURES
WILL LIKELY RANGE FROM 5 TO 20 BELOW. WITH TEMPERATURES THIS COLD...
ANY WIND AT ALL WILL PRODUCE WIND CHILLS IN THE ADVISORY CRITERIA
/20 TO 35 BELOW/.
EARLY NEXT WEEK...THE MODELS CONTINUE TO SHOW THAT A STRONG SUDDEN
STRATOSPHERIC WARMING EVENT WILL TAKE PLACE ACROSS THE NORTH
CENTRAL PACIFIC. THIS WILL RESULT IN A LONG WAVE TROUGH QUICKLY
DEVELOPING ACROSS THIS AREA. THIS IS TURN WILL GIVE AN EASTERN
NUDGE TO THE LONG WAVE RIDGE ACROSS THE EAST PACIFIC AND WESTERN
NORTH AMERICA. AS THIS OCCURS...THE COLDEST AIR SHOULD START TO
SHIFT OUT OF THE AREA ON TUESDAY AND TUESDAY NIGHT. BOTH THE
DETERMINISTIC AND ENSEMBLE MEMBERS SHOW THIS OCCURRING...SO
CONFIDENCE IS FAIRLY HIGH THAT THIS LATEST BOUT OF ARCTIC AIR WILL
BE A SHORT LIVED.
&&
.AVIATION...TODAY AND TONIGHT
521 AM CST WED JAN 16 2013
SOUTHWEST FLOW AHEAD OF THE SYSTEM MOVING INTO THE UPPER MIDWEST
IS STILL PRODUCING SOME WIND SHEAR AT KLSE. EXPECT THIS WILL
DISSIPATE BY MID MORNING AS A SURFACE TROUGH APPROACHES AND THE
WINDS ALOFT DECREASE AHEAD OF THIS FEATURE. CLOUDS AHEAD OF THE
SURFACE TROUGH INITIALLY START OUT VFR BUT THEN LOWER TO MVFR AS
IT GETS CLOSER. THE LIGHT SNOW THAT HAD BEEN ALONG THE SURFACE
TROUGH OVER SOUTH DAKOTA AND WESTERN MINNESOTA HAS
WEAKENED/DISSIPATED WITH JUST SOME FLURRIES LEFT. THE MAIN AREA OF
VISIBILITY REDUCING SNOW WILL PASS TO THE NORTH OF BOTH TAF SITES
CLOSER TO THE MAIN SURFACE LOW MOVING ACROSS SOUTHERN ONTARIO AND
LAKE SUPERIOR. THE WINDS WILL SWITCH TO THE WEST BEHIND THE
SURFACE TROUGH AND SWING AROUND TO THE NORTHWEST LATE THIS
AFTERNOON OR EARLY EVENING ONCE THE COLD FRONT GOES THROUGH. THE
MVFR CEILINGS SHOULD REMAIN IN PLACE BEHIND THE SURFACE TROUGH BUT
HOW LONG THEY HOLD ON BEHIND THE COLD FRONT IS UNKNOWN. CEILINGS
ARE PRIMARILY MVFR BACK ACROSS NORTH DAKOTA INTO MANITOBA AND
ALBERTA BUT THERE ARE SOME AREAS OF VFR AS WELL. FORECAST
SOUNDINGS FROM THE 16.06Z NAM SUGGESTS THAT DRIER AIR WILL MOVE IN
THIS EVENING AND ACTUALLY CLEAR SKIES OUT. HOWEVER...NOT CONFIDENT
ON THIS AS THE MODEL SHOWS DRY AIR CURRENTLY NEAR LAKE
WINNIPEG...WHERE SKIES ARE CLEAR...BUT MOVES THIS ACROSS THE GREAT
LAKES AND NOT OVER THE AREA THIS EVENING. WILL STAY PESSIMISTIC
AND KEEP CEILINGS MVFR UNTIL CLOUDS TRENDS BECOME MORE WELL
DEFINED.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
355 AM CST WED JAN 16 2013
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...ZT
LONG TERM...BOYNE
AVIATION...04